diff --git a/.dart_tool/package_config.json b/.dart_tool/package_config.json
index d50d6f5..284ed91 100644
--- a/.dart_tool/package_config.json
+++ b/.dart_tool/package_config.json
@@ -11,7 +11,7 @@
     "constraint, update this by running tools/generate_package_config.dart."
   ],
   "configVersion": 2,
-  "generated": "2021-11-15T17:34:02.415038",
+  "generated": "2021-12-10T17:31:54.553345",
   "generator": "tools/generate_package_config.dart",
   "packages": [
     {
@@ -262,7 +262,7 @@
       "name": "dev_compiler",
       "rootUri": "../pkg/dev_compiler",
       "packageUri": "lib/",
-      "languageVersion": "2.12"
+      "languageVersion": "2.15"
     },
     {
       "name": "devtools_server",
@@ -381,7 +381,7 @@
       "name": "js",
       "rootUri": "../pkg/js",
       "packageUri": "lib/",
-      "languageVersion": "2.12"
+      "languageVersion": "2.16"
     },
     {
       "name": "js_ast",
@@ -760,7 +760,7 @@
       "name": "vm",
       "rootUri": "../pkg/vm",
       "packageUri": "lib/",
-      "languageVersion": "2.12"
+      "languageVersion": "2.15"
     },
     {
       "name": "vm_service",
@@ -817,4 +817,4 @@
       "languageVersion": "2.12"
     }
   ]
-}
+}
\ No newline at end of file
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2c48329..0e43ad5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,19 @@
   error with an existing stack trace, instead of creating
   a new stack trace.
 
+#### `dart:io`
+
+- **Breaking Change** [#47769](https://github.com/dart-lang/sdk/issues/47769):
+The `Platform.packageRoot` API has been removed. It had been marked deprecated
+in 2018, as it doesn't work with any Dart 2.x release.
+- Add optional `sourcePort` parameter to `Socket.connect`, `Socket.startConnect`, `RawSocket.connect` and `RawSocket.startConnect`
+
+#### `dart:isolate`
+
+- **Breaking Change** [#47769](https://github.com/dart-lang/sdk/issues/47769):
+The `Isolate.packageRoot` API has been removed. It had been marked deprecated
+in 2018, as it doesn't work with any Dart 2.x release.
+
 ### Tools
 
 #### Dart command line
@@ -25,18 +38,45 @@
 
 [an issue]: https://github.com/dart-lang/sdk/issues/new
 
+- **Breaking Change** [#46100](https://github.com/dart-lang/sdk/issues/46100):
+  The standalone `dartdoc` tool has been
+  marked deprecated as previously announced.
+  Its replacement is the `dart doc` command.
+  Should you find any issues, or missing features, in the replacement
+  command, kindly file [an issue][].
+
+[an issue]: https://github.com/dart-lang/sdk/issues/new
+
 #### Linter
 
-Updated the Linter to `1.15.0`, which includes changes that
-- adds new lint: `use_decorated_box`.
+Updated the Linter to `1.17.1`, which includes changes that
+- adds new lint: `unnecessary_late`.
+- improves docs for `prefer_initializing_formals`.
+- updates `secure_pubspec_urls` to check `issue_tracker` and
+  `repository` entries.
+- adds new lint: `conditional_uri_does_not_exist`.
+- improves performance for
+  `missing_whitespace_between_adjacent_strings`.
+- adds new lint: `avoid_final_parameters`.
 - adds new lint: `no_leading_underscores_for_library_prefixes`.
 - adds new lint: `no_leading_underscores_for_local_identifiers`.
 - adds new lint: `secure_pubspec_urls`.
 - adds new lint: `sized_box_shrink_expand`.
-- adds new lint: `avoid_final_parameters`.
+- adds new lint: `use_decorated_box`.
 - improves docs for `omit_local_variable_types`.
 
-## 2.15.0
+## 2.15.1 - 2021-12-14
+
+This is a patch release that fixes:
+
+- an AOT compilation failure in some Flutter apps (issue [#47878][]).
+- `dart pub publish` for servers with a path in the URL (pr
+  [dart-lang/pub#3244][]).
+
+[#47878]: https://github.com/dart-lang/sdk/issues/47878
+[dart-lang/pub#3244]: https://github.com/dart-lang/pub/pull/3244
+
+## 2.15.0 - 2021-12-08
 
 ### Language
 
@@ -50,8 +90,8 @@
   instance to be passed as a closure, and similarly for static methods. This is
   commonly referred to as "closurizing" or "tearing off" a method. Constructors
   were not previously eligible for closurization, forcing users to explicitly
-  write wrapper functions when using constructors as first class functions, as
-  in the calls to `map()` in the following example:
+  write wrapper functions when using constructors as first class functions.
+  See the calls to `map()` in this example:
 
   ```dart
   class A {
@@ -73,9 +113,9 @@
   ```
 
   New in Dart 2.15, constructors are now allowed to be torn off. Named
-  constructors are closurized using their declared name (here `A.fromString`),
-  and unnamed closures are referred to for closurization using the keyword `new`
-  (here `A.new`). The example above may now be written as:
+  constructors are closurized using their declared name (here `A.fromString`).
+  To closurize unnamed constructors, use the keyword `new` (here `A.new`).
+  The above example may now be written as:
 
   ```dart
   class A {
@@ -97,11 +137,11 @@
   ```
 
   Constructors for generic classes may be torn off as generic functions, or
-  instantiated at the tear-off site. So in the following code, the tear-off
-  `G.new` used to initialize the variable `f` produces a generic function which
-  may be used to produce an instance of `G<T>` for any type `T` provided when
-  `f` is called. The tear-off `G<String>.new` used to initialize the variable
-  `g` on the other hand produces a non-generic function which may only be used
+  instantiated at the tear-off site. In the following example, the tear-off
+  `G.new` is used to initialize the variable `f` produces a generic function
+  which may be used to produce an instance of `G<T>` for any type `T` provided
+  when `f` is called. The tear-off `G<String>.new` is used to initialize the
+  variable `g` to produce a non-generic function which may only be used
   to produce instances of type `G<String>`.
 
   ```dart
@@ -118,7 +158,7 @@
   }
   ```
 
-[constructor tear-offs]: https://github.com/dart-lang/language/blob/master/accepted/future-releases/constructor-tearoffs/feature-specification.md
+[constructor tear-offs]: https://github.com/dart-lang/language/blob/master/accepted/2.15/constructor-tearoffs/feature-specification.md
 
 - **[Generic type literals][explicit instantiation]**: Previous Dart versions
   allowed class names to be used as type literals. So for example,`int` may be
@@ -192,14 +232,15 @@
   }
   ```
 
-[explicit instantiation]: https://github.com/dart-lang/language/blob/master/accepted/future-releases/constructor-tearoffs/feature-specification.md#explicitly-instantiated-classes-and-functions
+[explicit instantiation]: https://github.com/dart-lang/language/blob/master/accepted/2.15/constructor-tearoffs/feature-specification.md#explicitly-instantiated-classes-and-functions
 
 - **[Generic instantiation of function objects][object instantiation]**: Generic
   function instantiation was previously restricted to function declarations. For
-  example, as soon as a function had already been torn off, it could not be
+  example, as soon as a function had been torn off, it could not be
   instantiated:
 
   ```dart
+  // Before Dart 2.15:
   X id<X>(X x) => x;
 
   void main() {
@@ -210,7 +251,7 @@
   }
   ```
 
-  New in Dart 2.15, this restriction has been lifted, and it is now possible
+  New in Dart 2.15, this restriction has been lifted. It is now possible
   to obtain a generic instantiation of an existing function object, both
   explicitly and implicitly (again, this works the same for non-constants):
 
@@ -271,36 +312,36 @@
   }
   ```
 
-  Previously, the above program had a compile-time error because type promotion
-  due to a bug ([#1785][]) which prevented the initializer expression (`i ==
-  null`) from being accounted for when the variable in question (`iIsNull`)
-  lacked an explicit type.
+  Previously, the above program had a compile-time error due to a bug
+  ([#1785][]) in type promotion which prevented the initializer expression
+  (`i == null`) from being accounted for when the variable in question
+  (`iIsNull`) lacked an explicit type.
 
   To avoid causing problems for packages that are intended to work with older
-  versions of Dart, the fix only takes effect when the "constructor tear-offs"
-  language feature is enabled.
+  versions of Dart, the fix only takes effect when the minimum SDK of the source
+  packages is 2.15 or greater.
 
 [#1785]: https://github.com/dart-lang/language/issues/1785
 
 - Restrictions on members of a class with a constant constructor are relaxed
   such that they only apply when the class has a _generative_ constant
-  constructor.  For example, this used to be an error, but is now permitted:
+  constructor. For example, this used to be an error, but is now permitted:
 
   ```dart
   abstract class A {
+    const factory A() = B;
     var v1;
     late final v2 = Random().nextInt(10);
     late final v3;
-    const factory A() = B;
   }
 
   class B implements A {
+    const B([this.v3 = 1]);
     get v1 => null;
     set v1(_) => throw 'Cannot mutate B.v1';
     final v2 = 0;
     final v3;
     set v3(_) => throw 'Cannot initialize B.v3';
-    const B([this.v3 = 1]);
   }
   ```
 
@@ -316,7 +357,7 @@
   In particular, function objects are now equal when they are obtained by
   generic instantiation from the same function with the same actual type
   arguments, even when that type argument is not known at compile time.
-  When the expressions are constant then said function objects are identical.
+  When the expressions are constant then the function objects are identical.
   Constant expressions are treated as such even when they do not occur in a
   constant context (e.g., `var f = top;`).
 
@@ -325,14 +366,12 @@
 #### `dart:async`
 
 - Make the `unawaited` function's argument nullable, to allow calls like
-  `unawaited(foo?.bar())` too.
+  `unawaited(foo?.bar())`.
 
 #### `dart:cli`
 
 - The experimental `waitFor` functionality, and the library containing only that
   function, are now deprecated.
-- When a script is `dart run` it will always be precompiled, but with
-  incremental precompilation for following runs.
 
 #### `dart:core`
 
@@ -375,8 +414,8 @@
 #### `dart:html`
 
 - **Breaking Change** [#46316](https://github.com/dart-lang/sdk/issues/46316):
-  Related to the removal of `dart:web_sql` (see above), the
-  `window.openDatabase` has been removed as well.
+  Related to the removal of `dart:web_sql` (see above), `window.openDatabase`
+  has been removed.
 
 ### Tools
 
@@ -393,6 +432,9 @@
   Note that `dart format` has [a different set of options and
   defaults][dartfmt cli] than `dartfmt`.
 
+- When a script is `dart run` it will always be precompiled, but with
+  incremental precompilation for following runs.
+
 #### Dart VM
 
 - **Breaking Change** [#45451](https://github.com/dart-lang/sdk/issues/45451):
@@ -427,53 +469,48 @@
 #### Linter
 
 Updated the Linter to `1.14.0`, which includes changes that
-- fix `omit_local_variable_types` to not flag a local type that is
-  required for inference.
-- allow `while (true) { ... }` in `literal_only_boolean_expressions`.
-- fix `file_names` to report at the start of the file (not the entire
-  compilation unit).
-- fix `prefer_collection_literals` named typed parameter false positives.
-- improve control flow analysis for `use_build_context_synchronously`.
-- update `avoid_print` to allow `kDebugMode`-wrapped print calls.
-- fix handling of initializing formals in `prefer_final_parameters`.
-- fix `unnecessary_parenthesis` false positive with function expressions.
-- adds support for constructor tear-offs to `avoid_redundant_argument_values`,
-  `unnecessary_lambdas`, and `unnecessary_parenthesis`.
-- adds a new lint: `unnecessary_constructor_name` to flag unnecessary uses of
-  `.new`.
-- improves regular expression parsing performance for common checks
-  (`camel_case_types`, `file_names`, etc.).
-- (internal) migrates to analyzer 2.1.0 APIs.
-- fixes false positive in `use_build_context_synchronously` in awaits inside
-  anonymous functions.
-- fixes `overridden_fields` false positive w/ static fields.
-- fixes false positive in `avoid_null_checks_in_equality_operators` w/
-  non-nullable params.
-- fixes false positive for deferred imports in `prefer_const_constructors`.
-- marks `avoid_dynamic_calls` stable.
-- (internal) removes unused `MockPubVisitor` and `MockRule` classes.
-- fixes a `prefer_void_to_null` false positive w/ overridden properties.
-- (internal) removes references to `NodeLintRule` in lint rule declarations.
-- fixes `prefer_void_to_null` false positives on overriding returns.
-- fixes `prefer_generic_function_type_aliases` false positives w/ incomplete
-  statements.
-- fixes false positives for `prefer_initializing_formals` with factory
-  constructors.
-- fixes `void_checks` false positives with incomplete source.
-- updates `unnecessary_getters_setters` to only flag the getter.
-- improves messages for `avoid_renaming_method_parameters`.
-- fixes false positives in `prefer_void_to_null`.
-- fixes false positives in `omit_local_variable_types`.
-- fixes false positives in `use_rethrow_when_possible`.
 - improves performance for `annotate_overrides`, `prefer_contains`, and
   `prefer_void_to_null`.
+- marks `avoid_dynamic_calls` stable.
+- fixed `avoid_null_checks_in_equality_operators` false positive with
+  non-nullable params.
+- update `avoid_print` to allow `kDebugMode`-wrapped print calls.
+- adds support for constructor tear-offs to `avoid_redundant_argument_values`,
+  `unnecessary_lambdas`, and `unnecessary_parenthesis`.
+- improves messages for `avoid_renaming_method_parameters`.
+- improves regular expression parsing performance for common checks
+  (`camel_case_types`, `file_names`, etc.).
+- fixed `file_names` to report at the start of the file
+  (not the entire compilation unit).
+- allow `while (true) { ... }` in `literal_only_boolean_expressions`.
+- fixed `omit_local_variable_types` false positives.
+- fixed `omit_local_variable_types` to not flag a local type that is required
+  for inference.
+- fixed `overridden_fields` false positive with static fields.
+- fixed `prefer_collection_literals` named typed parameter false positives.
+- fixed `prefer_const_constructors` false positive for deferred imports.
+- fixed `prefer_final_parameters` handling of initializing formals.
+- fixed `prefer_generic_function_type_aliases` false positives with incomplete
+  statements.
+- fixed `prefer_initializing_formals` false positives with factory constructors.
+- fixed `prefer_void_to_null` false positive with overridden properties.
+- fixed `prefer_void_to_null` false positives on overriding returns.
+- fixed `prefer_void_to_null` false positives.
+- adds a new lint: `unnecessary_constructor_name` to flag unnecessary uses of
+  `.new`.
+- updates `unnecessary_getters_setters` to only flag the getter.
+- fixed `unnecessary_parenthesis` false positive with function expressions.
+- fixed `use_build_context_synchronously` false positive in awaits inside
+  anonymous functions.
+- improve control flow analysis for `use_build_context_synchronously`.
+- fixed `use_rethrow_when_possible` false positives.
+- fixed `void_checks` false positives with incomplete source.
 
 ### Pub
 
 - If you have analytics enabled `dart pub get` will send
   [usage metrics](https://github.com/dart-lang/pub/blob/0035a40f25d027130c0314571da53ffafc6d973b/lib/src/solver/result.dart#L131-L175)
   for packages from pub.dev, intended for popularity analysis.
-
 - Adds support for token-based authorization to third-party package-repositories
   with the new command `dart pub token`.
 - Credentials are no longer stored in the pub-cache, but in a platform dependent
@@ -485,7 +522,7 @@
 - The syntax for dependencies hosted at a third-party package repository has
   been simplified. Before you would need to write:
 
-```
+```yaml
 dependencies:
   colorizer:
     hosted:
@@ -498,7 +535,7 @@
 
 Now you can write:
 
-```
+```yaml
 dependencies:
   colorizer:
     hosted: 'https://custom-pub-server.com'
diff --git a/DEPS b/DEPS
index cec2977..b98102b 100644
--- a/DEPS
+++ b/DEPS
@@ -39,12 +39,12 @@
 
   # Checked-in SDK version. The checked-in SDK is a Dart SDK distribution in a
   # cipd package used to run Dart scripts in the build and test infrastructure.
-  "sdk_tag": "version:2.15.0-268.8.beta",
+  "sdk_tag": "version:2.15.1",
 
   # co19 is a cipd package. Use update.sh in tests/co19[_2] to update these
   # hashes. It requires access to the dart-build-access group, which EngProd
   # has.
-  "co19_rev": "4ef349830b971c22d8ddb2970c4ba9002806fd85",
+  "co19_rev": "a4144628905e0d3326b2549c9a1425bfca06c681",
   # This line prevents conflicts when both packages are rolled simultaneously.
   "co19_2_rev": "995745937abffe9fc3a6441f9f0db27b2d706e4c",
 
@@ -91,7 +91,7 @@
   "collection_rev": "a4c941ab94044d118b2086a3f261c30377604127",
   "convert_rev": "e063fdca4bebffecbb5e6aa5525995120982d9ce",
   "crypto_rev": "b5024e4de2b1c474dd558bef593ddbf0bfade152",
-  "csslib_rev": "02abc1ddf93092efef2be365300f15504d23cd23",
+  "csslib_rev": "158bfa94eed08c12c07a8ee0a3fded0ebdcd1fcb",
 
   # Note: Updates to dart_style have to be coordinated with the infrastructure
   # team so that the internal formatter `tools/sdks/dart-sdk/bin/dart format`
@@ -107,8 +107,8 @@
   # For more details, see https://github.com/dart-lang/sdk/issues/30164
   "dart_style_rev": "08b0294d0a500d5c02168ef57dcb8868d0c3cb48",
 
-  "dartdoc_rev" : "ff0d94bdb87f11c04a7e0ddab811bf94211b08a4",
-  "devtools_rev" : "f2ede24a4ea666d4832d78b813c7d4e376aa77d0",
+  "dartdoc_rev" : "11c4b3c9723bfa7155efcf0fef02329233a6381d",
+  "devtools_rev" : "85932bb66aa782c4b2c528be7718960bf256ffb7",
   "jsshell_tag": "version:88.0",
   "ffi_rev": "4dd32429880a57b64edaf54c9d5af8a9fa9a4ffb",
   "fixnum_rev": "16d3890c6dc82ca629659da1934e412292508bba",
@@ -123,7 +123,7 @@
   "intl_tag": "0.17.0-nullsafety",
   "jinja2_rev": "2222b31554f03e62600cd7e383376a7c187967a1",
   "json_rpc_2_rev": "7e00f893440a72de0637970325e4ea44bd1e8c8e",
-  "linter_tag": "1.15.0",
+  "linter_tag": "1.17.1",
   "lints_tag": "f9670df2a66e0ec12eb51554e70c1cbf56c8f5d0",
   "logging_rev": "575781ef196e4fed4fb737e38fb4b73d62727187",
   "markupsafe_rev": "8f45f5cfa0009d2a70589bcda0349b8cb2b72783",
@@ -133,9 +133,9 @@
   "mockito_rev": "d39ac507483b9891165e422ec98d9fb480037c8b",
   "oauth2_rev": "7cd3284049fe5badbec9f2bea2afc41d14c01057",
   "package_config_rev": "fb736aa12316dd2d882b202a438a6946a4b4bea0",
-  "path_rev": "c20d73c3516d3a0061c90f14b761ff532b9bf707",
+  "path_rev": "baedce9d2ca11ea2cdf54395a74eb038087777a4",
   "pedantic_rev": "66f2f6c27581c7936482e83be80b27be2719901c",
-  "platform_rev": "c20e6fa315e9f8820e51c0ae721f63aff33b8e17",
+  "platform_rev": "1ffad63428bbd1b3ecaa15926bacfb724023648c",
   "ply_rev": "604b32590ffad5cbb82e4afef1d305512d06ae93",
   "pool_rev": "7abe634002a1ba8a0928eded086062f1307ccfae",
   "process_rev": "56ece43b53b64c63ae51ec184b76bd5360c28d0b",
@@ -278,7 +278,7 @@
   Var("dart_root") + "/third_party/gsutil": {
       "packages": [{
           "package": "infra/3pp/tools/gsutil",
-          "version": "version:4.58",
+          "version": "version:2@5.5",
       }],
       "dep_type": "cipd",
   },
diff --git a/benchmarks/FfiMemory/dart/FfiMemory.dart b/benchmarks/FfiMemory/dart/FfiMemory.dart
index 26ff8e7..686d6bd 100644
--- a/benchmarks/FfiMemory/dart/FfiMemory.dart
+++ b/benchmarks/FfiMemory/dart/FfiMemory.dart
@@ -15,6 +15,34 @@
 import 'package:ffi/ffi.dart';
 import 'package:benchmark_harness/benchmark_harness.dart';
 
+/// Represents a native unsigned pointer-sized integer in C.
+///
+/// [UintPtr] is not constructible in the Dart code and serves purely as marker in
+/// type signatures.
+@AbiSpecificIntegerMapping({
+  Abi.androidArm: Uint32(),
+  Abi.androidArm64: Uint64(),
+  Abi.androidIA32: Uint32(),
+  Abi.androidX64: Uint64(),
+  Abi.fuchsiaArm64: Uint64(),
+  Abi.fuchsiaX64: Uint64(),
+  Abi.iosArm: Uint32(),
+  Abi.iosArm64: Uint64(),
+  Abi.iosX64: Uint64(),
+  Abi.linuxArm: Uint32(),
+  Abi.linuxArm64: Uint64(),
+  Abi.linuxIA32: Uint32(),
+  Abi.linuxX64: Uint64(),
+  Abi.macosArm64: Uint64(),
+  Abi.macosX64: Uint64(),
+  Abi.windowsArm64: Uint64(),
+  Abi.windowsIA32: Uint32(),
+  Abi.windowsX64: Uint64(),
+})
+class UintPtr extends AbiSpecificInteger {
+  const UintPtr();
+}
+
 //
 // Pointer store.
 //
@@ -73,6 +101,12 @@
   }
 }
 
+void doStoreUintPtr(Pointer<UintPtr> pointer, int length) {
+  for (int i = 0; i < length; i++) {
+    pointer[i] = 1;
+  }
+}
+
 void doStoreFloat(Pointer<Float> pointer, int length) {
   for (int i = 0; i < length; i++) {
     pointer[i] = 1.0;
@@ -174,6 +208,14 @@
   return x;
 }
 
+int doLoadUintPtr(Pointer<UintPtr> pointer, int length) {
+  int x = 0;
+  for (int i = 0; i < length; i++) {
+    x += pointer[i];
+  }
+  return x;
+}
+
 double doLoadFloat(Pointer<Float> pointer, int length) {
   double x = 0;
   for (int i = 0; i < length; i++) {
@@ -452,6 +494,25 @@
   }
 }
 
+class PointerUintPtr extends BenchmarkBase {
+  Pointer<UintPtr> pointer = nullptr;
+  PointerUintPtr() : super('FfiMemory.PointerUintPtr');
+
+  @override
+  void setup() => pointer = calloc(N);
+  @override
+  void teardown() => calloc.free(pointer);
+
+  @override
+  void run() {
+    doStoreUintPtr(pointer, N);
+    final int x = doLoadUintPtr(pointer, N);
+    if (x != N) {
+      throw Exception('$name: Unexpected result: $x');
+    }
+  }
+}
+
 class PointerFloat extends BenchmarkBase {
   Pointer<Float> pointer = nullptr;
   PointerFloat() : super('FfiMemory.PointerFloat');
@@ -555,6 +616,7 @@
     () => PointerInt64(),
     () => PointerInt64Mint(),
     () => PointerUint64(),
+    () => PointerUintPtr(),
     () => PointerFloat(),
     () => PointerDouble(),
     () => PointerPointer(),
diff --git a/benchmarks/FfiMemory/dart2/FfiMemory.dart b/benchmarks/FfiMemory/dart2/FfiMemory.dart
index 8ed6302..a170aaa 100644
--- a/benchmarks/FfiMemory/dart2/FfiMemory.dart
+++ b/benchmarks/FfiMemory/dart2/FfiMemory.dart
@@ -17,6 +17,34 @@
 import 'package:ffi/ffi.dart';
 import 'package:benchmark_harness/benchmark_harness.dart';
 
+/// Represents a native unsigned pointer-sized integer in C.
+///
+/// [UintPtr] is not constructible in the Dart code and serves purely as marker in
+/// type signatures.
+@AbiSpecificIntegerMapping({
+  Abi.androidArm: Uint32(),
+  Abi.androidArm64: Uint64(),
+  Abi.androidIA32: Uint32(),
+  Abi.androidX64: Uint64(),
+  Abi.fuchsiaArm64: Uint64(),
+  Abi.fuchsiaX64: Uint64(),
+  Abi.iosArm: Uint32(),
+  Abi.iosArm64: Uint64(),
+  Abi.iosX64: Uint64(),
+  Abi.linuxArm: Uint32(),
+  Abi.linuxArm64: Uint64(),
+  Abi.linuxIA32: Uint32(),
+  Abi.linuxX64: Uint64(),
+  Abi.macosArm64: Uint64(),
+  Abi.macosX64: Uint64(),
+  Abi.windowsArm64: Uint64(),
+  Abi.windowsIA32: Uint32(),
+  Abi.windowsX64: Uint64(),
+})
+class UintPtr extends AbiSpecificInteger {
+  const UintPtr();
+}
+
 //
 // Pointer store.
 //
@@ -75,6 +103,12 @@
   }
 }
 
+void doStoreUintPtr(Pointer<UintPtr> pointer, int length) {
+  for (int i = 0; i < length; i++) {
+    pointer[i] = 1;
+  }
+}
+
 void doStoreFloat(Pointer<Float> pointer, int length) {
   for (int i = 0; i < length; i++) {
     pointer[i] = 1.0;
@@ -176,6 +210,14 @@
   return x;
 }
 
+int doLoadUintPtr(Pointer<UintPtr> pointer, int length) {
+  int x = 0;
+  for (int i = 0; i < length; i++) {
+    x += pointer[i];
+  }
+  return x;
+}
+
 double doLoadFloat(Pointer<Float> pointer, int length) {
   double x = 0;
   for (int i = 0; i < length; i++) {
@@ -391,7 +433,7 @@
 }
 
 class PointerUint32Unaligned extends BenchmarkBase {
-  Pointer<Float> pointer;
+  Pointer<Uint32> pointer;
   Pointer<Uint32> unalignedPointer;
   PointerUint32Unaligned() : super('FfiMemory.PointerUint32Unaligned');
 
@@ -452,6 +494,25 @@
   }
 }
 
+class PointerUintPtr extends BenchmarkBase {
+  Pointer<UintPtr> pointer;
+  PointerUintPtr() : super('FfiMemory.PointerUintPtr');
+
+  @override
+  void setup() => pointer = calloc(N);
+  @override
+  void teardown() => calloc.free(pointer);
+
+  @override
+  void run() {
+    doStoreUintPtr(pointer, N);
+    final int x = doLoadUintPtr(pointer, N);
+    if (x != N) {
+      throw Exception('$name: Unexpected result: $x');
+    }
+  }
+}
+
 class PointerFloat extends BenchmarkBase {
   Pointer<Float> pointer;
   PointerFloat() : super('FfiMemory.PointerFloat');
@@ -555,6 +616,7 @@
     () => PointerInt64(),
     () => PointerInt64Mint(),
     () => PointerUint64(),
+    () => PointerUintPtr(),
     () => PointerFloat(),
     () => PointerDouble(),
     () => PointerPointer(),
diff --git a/client/.gitignore b/client/.gitignore
deleted file mode 100644
index 067c596..0000000
--- a/client/.gitignore
+++ /dev/null
@@ -1,5 +0,0 @@
-/Makefile
-/out
-/xcodebuild
-/dart.xcodeproj
-/tests
diff --git a/client/dart.js b/client/dart.js
deleted file mode 100644
index 43a6497..0000000
--- a/client/dart.js
+++ /dev/null
@@ -1,265 +0,0 @@
-// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-var warning = [
-  'WARNING: This page is using a deprecated dart.js file. ',
-  'Please update this page as described here: ',
-  'http://news.dartlang.org/2013/01/big-breaking-change-dartjs-bootstrap-file-moving-to-pub.html'
-].join('');
-console.error(warning);
-
-// Bootstrap support for Dart scripts on the page as this script.
-if (navigator.userAgent.indexOf('(Dart)') === -1) {
-  // TODO:
-  // - Support in-browser compilation.
-  // - Handle inline Dart scripts.
-  window.addEventListener("DOMContentLoaded", function (e) {
-    // Fall back to compiled JS. Run through all the scripts and
-    // replace them if they have a type that indicate that they source
-    // in Dart code.
-    //
-    //   <script type="application/dart" src="..."></script>
-    //
-    var scripts = document.getElementsByTagName("script");
-    var length = scripts.length;
-    for (var i = 0; i < length; ++i) {
-      if (scripts[i].type == "application/dart") {
-        // Remap foo.dart to foo.dart.js.
-        if (scripts[i].src && scripts[i].src != '') {
-          var script = document.createElement('script');
-          script.src = scripts[i].src + '.js';
-          var parent = scripts[i].parentNode;
-          parent.replaceChild(script, scripts[i]);
-        }
-      }
-    }
-  }, false);
-}
-
-// ---------------------------------------------------------------------------
-// Experimental support for JS interoperability
-// ---------------------------------------------------------------------------
-function SendPortSync() {
-}
-
-function ReceivePortSync() {
-  this.id = ReceivePortSync.id++;
-  ReceivePortSync.map[this.id] = this;
-}
-
-(function() {
-  // Serialize the following types as follows:
-  //  - primitives / null: unchanged
-  //  - lists: [ 'list', internal id, list of recursively serialized elements ]
-  //  - maps: [ 'map', internal id, map of keys and recursively serialized values ]
-  //  - send ports: [ 'sendport', type, isolate id, port id ]
-  //
-  // Note, internal id's are for cycle detection.
-  function serialize(message) {
-    var visited = [];
-    function checkedSerialization(obj, serializer) {
-      // Implementation detail: for now use linear search.
-      // Another option is expando, but it may prohibit
-      // VM optimizations (like putting object into slow mode
-      // on property deletion.)
-      var id = visited.indexOf(obj);
-      if (id != -1) return [ 'ref', id ];
-      var id = visited.length;
-      visited.push(obj);
-      return serializer(id);
-    }
-
-    function doSerialize(message) {
-      if (message == null) {
-        return null;  // Convert undefined to null.
-      } else if (typeof(message) == 'string' ||
-                 typeof(message) == 'number' ||
-                 typeof(message) == 'boolean') {
-        return message;
-      } else if (message instanceof Array) {
-        return checkedSerialization(message, function(id) {
-          var values = new Array(message.length);
-          for (var i = 0; i < message.length; i++) {
-            values[i] = doSerialize(message[i]);
-          }
-          return [ 'list', id, values ];
-        });
-      } else if (message instanceof LocalSendPortSync) {
-        return [ 'sendport', 'nativejs', message.receivePort.id ];
-      } else if (message instanceof DartSendPortSync) {
-        return [ 'sendport', 'dart', message.isolateId, message.portId ];
-      } else {
-        return checkedSerialization(message, function(id) {
-          var keys = Object.getOwnPropertyNames(message);
-          var values = new Array(keys.length);
-          for (var i = 0; i < keys.length; i++) {
-            values[i] = doSerialize(message[keys[i]]);
-          }
-          return [ 'map', id, keys, values ];
-        });
-      }
-    }
-    return doSerialize(message);
-  }
-
-  function deserialize(message) {
-    return deserializeHelper(message);
-  }
-
-  function deserializeHelper(message) {
-    if (message == null ||
-        typeof(message) == 'string' ||
-        typeof(message) == 'number' ||
-        typeof(message) == 'boolean') {
-      return message;
-    }
-    switch (message[0]) {
-      case 'map': return deserializeMap(message);
-      case 'sendport': return deserializeSendPort(message);
-      case 'list': return deserializeList(message);
-      default: throw 'unimplemented';
-    }
-  }
-
-  function deserializeMap(message) {
-    var result = { };
-    var id = message[1];
-    var keys = message[2];
-    var values = message[3];
-    for (var i = 0, length = keys.length; i < length; i++) {
-      var key = deserializeHelper(keys[i]);
-      var value = deserializeHelper(values[i]);
-      result[key] = value;
-    }
-    return result;
-  }
-
-  function deserializeSendPort(message) {
-    var tag = message[1];
-    switch (tag) {
-      case 'nativejs':
-        var id = message[2];
-        return new LocalSendPortSync(ReceivePortSync.map[id]);
-      case 'dart':
-        var isolateId = message[2];
-        var portId = message[3];
-        return new DartSendPortSync(isolateId, portId);
-      default:
-        throw 'Illegal SendPortSync type: $tag';
-    }
-  }
-
-  function deserializeList(message) {
-    var values = message[2];
-    var length = values.length;
-    var result = new Array(length);
-    for (var i = 0; i < length; i++) {
-      result[i] = deserializeHelper(values[i]);
-    }
-    return result;
-  }
-
-  window.registerPort = function(name, port) {
-    var stringified = JSON.stringify(serialize(port));
-    var attrName = 'dart-port:' + name;
-    document.documentElement.setAttribute(attrName, stringified);
-    // TODO(vsm): Phase out usage of localStorage and delete the
-    // below.  We're leaving it in temporarily for backwards
-    // compatibility.
-    try {
-      window.localStorage[attrName] = stringified;
-    } catch (e) {
-      // Swallow errors (e.g., Chrome apps disallow this access).
-    }
-  };
-
-  window.lookupPort = function(name) {
-    var attrName = 'dart-port:' + name;
-    var stringified = document.documentElement.getAttribute(attrName);
-    // TODO(vsm): Phase out usage of localStorage.  We're leaving it in
-    // temporarily for backwards compatibility.
-    if (!stringified) {
-      stringified = window.localStorage[attrName];
-    }
-    return deserialize(JSON.parse(stringified));
-  };
-
-  ReceivePortSync.id = 0;
-  ReceivePortSync.map = {};
-
-  ReceivePortSync.dispatchCall = function(id, message) {
-    // TODO(vsm): Handle and propagate exceptions.
-    var deserialized = deserialize(message);
-    var result = ReceivePortSync.map[id].callback(deserialized);
-    return serialize(result);
-  };
-
-  ReceivePortSync.prototype.receive = function(callback) {
-    this.callback = callback;
-  };
-
-  ReceivePortSync.prototype.toSendPort = function() {
-    return new LocalSendPortSync(this);
-  };
-
-  ReceivePortSync.prototype.close = function() {
-    delete ReceivePortSync.map[this.id];
-  };
-
-  if (navigator.userAgent.indexOf('(Dart)') !== -1) {
-    window.addEventListener('js-sync-message', function(event) {
-      var data = JSON.parse(getPortSyncEventData(event));
-      var deserialized = deserialize(data.message);
-      var result = ReceivePortSync.map[data.id].callback(deserialized);
-      // TODO(vsm): Handle and propagate exceptions.
-      dispatchEvent('js-result', serialize(result));
-    }, false);
-  }
-
-  function LocalSendPortSync(receivePort) {
-    this.receivePort = receivePort;
-  }
-
-  LocalSendPortSync.prototype = new SendPortSync();
-
-  LocalSendPortSync.prototype.callSync = function(message) {
-    // TODO(vsm): Do a direct deepcopy.
-    message = deserialize(serialize(message));
-    return this.receivePort.callback(message);
-  }
-
-  function DartSendPortSync(isolateId, portId) {
-    this.isolateId = isolateId;
-    this.portId = portId;
-  }
-
-  DartSendPortSync.prototype = new SendPortSync();
-
-  function dispatchEvent(receiver, message) {
-    var string = JSON.stringify(message);
-    var event = document.createEvent('CustomEvent');
-    event.initCustomEvent(receiver, false, false, string);
-    window.dispatchEvent(event);
-  }
-
-  function getPortSyncEventData(event) {
-    return event.detail;
-  }
-
-  DartSendPortSync.prototype.callSync = function(message) {
-    var serialized = serialize(message);
-    var target = 'dart-port-' + this.isolateId + '-' + this.portId;
-    // TODO(vsm): Make this re-entrant.
-    // TODO(vsm): Set this up set once, on the first call.
-    var source = target + '-result';
-    var result = null;
-    var listener = function (e) {
-      result = JSON.parse(getPortSyncEventData(e));
-    };
-    window.addEventListener(source, listener, false);
-    dispatchEvent(target, [source, serialized]);
-    window.removeEventListener(source, listener, false);
-    return deserialize(result);
-  }
-})();
diff --git a/client/idea/.idea/.name b/client/idea/.idea/.name
deleted file mode 100644
index ad82b85..0000000
--- a/client/idea/.idea/.name
+++ /dev/null
@@ -1 +0,0 @@
-sdk
\ No newline at end of file
diff --git a/client/idea/.idea/inspectionProfiles/Project_Default.xml b/client/idea/.idea/inspectionProfiles/Project_Default.xml
deleted file mode 100644
index 9b0c20c..0000000
--- a/client/idea/.idea/inspectionProfiles/Project_Default.xml
+++ /dev/null
@@ -1,10 +0,0 @@
-<component name="InspectionProjectProfileManager">
-  <profile version="1.0">
-    <option name="myName" value="Project Default" />
-    <inspection_tool class="DartOutdatedDependencies" enabled="false" level="WARNING" enabled_by_default="false" />
-    <inspection_tool class="LoggerInitializedWithForeignClass" enabled="false" level="WARNING" enabled_by_default="false">
-      <option name="loggerClassName" value="org.apache.log4j.Logger,org.slf4j.LoggerFactory,org.apache.commons.logging.LogFactory,java.util.logging.Logger" />
-      <option name="loggerFactoryMethodName" value="getLogger,getLogger,getLog,getLogger" />
-    </inspection_tool>
-  </profile>
-</component>
\ No newline at end of file
diff --git a/client/idea/.idea/vcs.xml b/client/idea/.idea/vcs.xml
deleted file mode 100644
index b2bdec2..0000000
--- a/client/idea/.idea/vcs.xml
+++ /dev/null
@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="VcsDirectoryMappings">
-    <mapping directory="$PROJECT_DIR$/../.." vcs="Git" />
-  </component>
-</project>
\ No newline at end of file
diff --git a/client/idea/readme.md b/client/idea/readme.md
deleted file mode 100644
index f463828..0000000
--- a/client/idea/readme.md
+++ /dev/null
@@ -1,20 +0,0 @@
-# Working on the SDK repo using IntelliJ
-
-To work on Dart code in the SDK repo, we recommend either IntelliJ Community
-Edition or IntelliJ Ultimate.
-
-## Opening from IntelliJ
-
-To open the sdk repo using IntelliJ, choose `File` > `Open...` and select the
-`<sdk>/client/idea` directory.
-
-## Opening from the command-line
-
-To open from the command-line, type:
-
-```
-idea <sdk>/client/idea
-```
-
-This depends on having previously set up the IntelliJ command-line launcher. To
-do this, from the `Tools` menu, select `Create Command-line Launcher...`.
diff --git a/pkg/_fe_analyzer_shared/lib/src/base/errors.dart b/pkg/_fe_analyzer_shared/lib/src/base/errors.dart
index eb92d87..bcaa62b 100644
--- a/pkg/_fe_analyzer_shared/lib/src/base/errors.dart
+++ b/pkg/_fe_analyzer_shared/lib/src/base/errors.dart
@@ -50,17 +50,14 @@
     this.hasPublishedDocs = false,
     this.isUnresolvedIdentifier: false,
     required this.name,
-    @Deprecated('Please use problemMessage') String? message,
-    String? problemMessage,
+    required String problemMessage,
     required this.uniqueName,
   })  : _correctionMessage = correctionMessage,
-        _problemMessage = problemMessage ?? message ?? 'NO MESSAGE',
+        _problemMessage = problemMessage,
         // ignore: unnecessary_null_comparison
         assert(hasPublishedDocs != null),
         // ignore: unnecessary_null_comparison
-        assert(isUnresolvedIdentifier != null),
-        assert((message == null) != (problemMessage == null),
-            'Either problemMessage or message must be provided (not both)');
+        assert(isUnresolvedIdentifier != null);
 
   /**
    * The template used to create the correction to be displayed for this error,
diff --git a/pkg/_fe_analyzer_shared/lib/src/macros/api.dart b/pkg/_fe_analyzer_shared/lib/src/macros/api.dart
new file mode 100644
index 0000000..5d5c262
--- /dev/null
+++ b/pkg/_fe_analyzer_shared/lib/src/macros/api.dart
@@ -0,0 +1,10 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:async';
+
+part 'api/builders.dart';
+part 'api/code.dart';
+part 'api/introspection.dart';
+part 'api/macros.dart';
diff --git a/pkg/_fe_analyzer_shared/lib/src/macros/api/builders.dart b/pkg/_fe_analyzer_shared/lib/src/macros/api/builders.dart
new file mode 100644
index 0000000..74bf73c
--- /dev/null
+++ b/pkg/_fe_analyzer_shared/lib/src/macros/api/builders.dart
@@ -0,0 +1,159 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+part of '../api.dart';
+
+/// The base interface used to add declarations to the program as well
+/// as augment existing ones.
+abstract class Builder {}
+
+/// The api used by [Macro]s to contribute new type declarations to the
+/// current library, and get [TypeAnnotation]s from runtime [Type] objects.
+abstract class TypeBuilder implements Builder {
+  /// Adds a new type declaration to the surrounding library.
+  void declareType(DeclarationCode typeDeclaration);
+}
+
+/// The interface to resolve a [TypeAnnotation] to a [StaticType].
+///
+/// The [StaticType]s can be compared against other [StaticType]s to see how
+/// they relate to each other.
+///
+/// This api is only available to the declaration and definition phases of
+/// macro expansion.
+abstract class TypeResolver {
+  /// Resolves [typeAnnotation] to a [StaticType].
+  ///
+  /// Throws an error if the type annotation cannot be resolved. This should
+  /// only happen in the case of incomplete or invalid programs, but macros
+  /// may be asked to run in this state during the development cycle. It is
+  /// helpful for users if macros provide a best effort implementation in that
+  /// case or handle the error in a useful way.
+  Future<StaticType> resolve(TypeAnnotation typeAnnotation);
+}
+
+/// The api used to introspect on a [ClassDeclaration].
+///
+/// Available in the declaration and definition phases, but limited in the
+/// declaration phase to immediately annotated [ClassDeclaration]s. This is
+/// done by limiting the access to the [TypeDeclarationResolver] to the
+/// definition phase.
+abstract class ClassIntrospector {
+  /// The fields available for [clazz].
+  ///
+  /// This may be incomplete if in the declaration phase and additional macros
+  /// are going to run on this class.
+  Future<List<FieldDeclaration>> fieldsOf(ClassDeclaration clazz);
+
+  /// The methods available so far for the current class.
+  ///
+  /// This may be incomplete if additional declaration macros are running on
+  /// this class.
+  Future<List<MethodDeclaration>> methodsOf(ClassDeclaration clazz);
+
+  /// The constructors available so far for the current class.
+  ///
+  /// This may be incomplete if additional declaration macros are running on
+  /// this class.
+  Future<List<ConstructorDeclaration>> constructorsOf(ClassDeclaration clazz);
+
+  /// The class that is directly extended via an `extends` clause.
+  Future<ClassDeclaration?> superclassOf(ClassDeclaration clazz);
+
+  /// All of the classes that are mixed in with `with` clauses.
+  Future<List<ClassDeclaration>> mixinsOf(ClassDeclaration clazz);
+
+  /// All of the classes that are implemented with an `implements` clause.
+  Future<List<ClassDeclaration>> interfacesOf(ClassDeclaration clazz);
+}
+
+/// The api used by [Macro]s to contribute new (non-type)
+/// declarations to the current library.
+///
+/// Can also be used to do subtype checks on types.
+abstract class DeclarationBuilder
+    implements Builder, TypeResolver, ClassIntrospector {
+  /// Adds a new regular declaration to the surrounding library.
+  ///
+  /// Note that type declarations are not supported.
+  void declareInLibrary(DeclarationCode declaration);
+}
+
+/// The api used by [Macro]s to contribute new members to a class.
+abstract class ClassMemberDeclarationBuilder implements DeclarationBuilder {
+  /// Adds a new declaration to the surrounding class.
+  void declareInClass(DeclarationCode declaration);
+}
+
+/// The api used by [Macro]s to reflect on the currently available
+/// members, superclass, and mixins for a given [ClassDeclaration]
+abstract class ClassDeclarationBuilder
+    implements ClassMemberDeclarationBuilder, ClassIntrospector {}
+
+/// The interface used by [Macro]s to resolve any [NamedStaticType] to its
+/// declaration.
+///
+/// Only available in the definition phase of macro expansion.
+abstract class TypeDeclarationResolver {
+  /// Resolves a [NamedStaticType] to its [TypeDeclaration].
+  Future<TypeDeclaration> declarationOf(NamedStaticType annotation);
+}
+
+/// The base class for builders in the definition phase. These can convert
+/// any [TypeAnnotation] into its corresponding [TypeDeclaration], and also
+/// reflect more deeply on those.
+abstract class DefinitionBuilder
+    implements
+        Builder,
+        TypeResolver,
+        ClassIntrospector,
+        TypeDeclarationResolver {}
+
+/// The apis used by [Macro]s that run on classes, to fill in the definitions
+/// of any external declarations within that class.
+abstract class ClassDefinitionBuilder implements DefinitionBuilder {
+  /// Retrieve a [VariableDefinitionBuilder] for a field by [name].
+  ///
+  /// Throws an [ArgumentError] if there is no field by that name.
+  VariableDefinitionBuilder buildField(String name);
+
+  /// Retrieve a [FunctionDefinitionBuilder] for a method by [name].
+  ///
+  /// Throws an [ArgumentError] if there is no method by that name.
+  FunctionDefinitionBuilder buildMethod(String name);
+
+  /// Retrieve a [ConstructorDefinitionBuilder] for a constructor by [name].
+  ///
+  /// Throws an [ArgumentError] if there is no constructor by that name.
+  ConstructorDefinitionBuilder buildConstructor(String name);
+}
+
+/// The apis used by [Macro]s to define the body of a constructor
+/// or wrap the body of an existing constructor with additional statements.
+abstract class ConstructorDefinitionBuilder implements DefinitionBuilder {
+  /// Augments an existing constructor body with [body].
+  ///
+  /// TODO: Link the library augmentations proposal to describe the semantics.
+  void augment({FunctionBodyCode? body, List<Code>? initializers});
+}
+
+/// The apis used by [Macro]s to augment functions or methods.
+abstract class FunctionDefinitionBuilder implements DefinitionBuilder {
+  /// Augments the function.
+  ///
+  /// TODO: Link the library augmentations proposal to describe the semantics.
+  void augment(FunctionBodyCode body);
+}
+
+/// The api used by [Macro]s to augment a top level variable or instance field.
+abstract class VariableDefinitionBuilder implements DefinitionBuilder {
+  /// Augments the field.
+  ///
+  /// TODO: Link the library augmentations proposal to describe the semantics.
+  void augment({
+    DeclarationCode? getter,
+    DeclarationCode? setter,
+    ExpressionCode? initializer,
+  });
+}
diff --git a/pkg/_fe_analyzer_shared/lib/src/macros/api/code.dart b/pkg/_fe_analyzer_shared/lib/src/macros/api/code.dart
new file mode 100644
index 0000000..89f169f
--- /dev/null
+++ b/pkg/_fe_analyzer_shared/lib/src/macros/api/code.dart
@@ -0,0 +1,104 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+part of '../api.dart';
+
+/// The base class representing an arbitrary chunk of Dart code, which may or
+/// may not be syntactically or semantically valid yet.
+class Code {
+  /// All the chunks of [Code] or raw [String]s that comprise this [Code]
+  /// object.
+  final List<Object> parts;
+
+  Code.fromString(String code) : parts = [code];
+
+  Code.fromParts(this.parts);
+}
+
+/// A piece of code representing a syntactically valid declaration.
+class DeclarationCode extends Code {
+  DeclarationCode.fromString(String code) : super.fromString(code);
+
+  DeclarationCode.fromParts(List<Object> parts) : super.fromParts(parts);
+}
+
+/// A piece of code representing a syntactically valid element.
+///
+/// Should not include any trailing commas,
+class ElementCode extends Code {
+  ElementCode.fromString(String code) : super.fromString(code);
+
+  ElementCode.fromParts(List<Object> parts) : super.fromParts(parts);
+}
+
+/// A piece of code representing a syntactically valid expression.
+class ExpressionCode extends Code {
+  ExpressionCode.fromString(String code) : super.fromString(code);
+
+  ExpressionCode.fromParts(List<Object> parts) : super.fromParts(parts);
+}
+
+/// A piece of code representing a syntactically valid function body.
+///
+/// This includes any and all code after the parameter list of a function,
+/// including modifiers like `async`.
+///
+/// Both arrow and block function bodies are allowed.
+class FunctionBodyCode extends Code {
+  FunctionBodyCode.fromString(String code) : super.fromString(code);
+
+  FunctionBodyCode.fromParts(List<Object> parts) : super.fromParts(parts);
+}
+
+/// A piece of code representing a syntactically valid identifier.
+class IdentifierCode extends Code {
+  IdentifierCode.fromString(String code) : super.fromString(code);
+
+  IdentifierCode.fromParts(List<Object> parts) : super.fromParts(parts);
+}
+
+/// A piece of code identifying a named argument.
+///
+/// This should not include any trailing commas.
+class NamedArgumentCode extends Code {
+  NamedArgumentCode.fromString(String code) : super.fromString(code);
+
+  NamedArgumentCode.fromParts(List<Object> parts) : super.fromParts(parts);
+}
+
+/// A piece of code identifying a syntactically valid function parameter.
+///
+/// This should not include any trailing commas, but may include modifiers
+/// such as `required`, and default values.
+///
+/// There is no distinction here made between named and positional parameters,
+/// nor between optional or required parameters. It is the job of the user to
+/// construct and combine these together in a way that creates valid parameter
+/// lists.
+class ParameterCode extends Code {
+  ParameterCode.fromString(String code) : super.fromString(code);
+
+  ParameterCode.fromParts(List<Object> parts) : super.fromParts(parts);
+}
+
+/// A piece of code representing a syntactically valid statement.
+///
+/// Should always end with a semicolon.
+class StatementCode extends Code {
+  StatementCode.fromString(String code) : super.fromString(code);
+
+  StatementCode.fromParts(List<Object> parts) : super.fromParts(parts);
+}
+
+extension Join<T extends Code> on List<T> {
+  /// Joins all the items in [this] with [separator], and returns
+  /// a new list.
+  List<Code> joinAsCode(String separator) => [
+        for (int i = 0; i < length - 1; i++) ...[
+          this[i],
+          new Code.fromString(separator),
+        ],
+        last,
+      ];
+}
diff --git a/pkg/_fe_analyzer_shared/lib/src/macros/api/introspection.dart b/pkg/_fe_analyzer_shared/lib/src/macros/api/introspection.dart
new file mode 100644
index 0000000..e892296
--- /dev/null
+++ b/pkg/_fe_analyzer_shared/lib/src/macros/api/introspection.dart
@@ -0,0 +1,192 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+part of '../api.dart';
+
+/// The base class for an unresolved reference to a type.
+///
+/// See the subtypes [FunctionTypeAnnotation] and [NamedTypeAnnotation].
+abstract class TypeAnnotation {
+  /// Whether or not the type annotation is explicitly nullable (contains a
+  /// trailing `?`)
+  bool get isNullable;
+
+  /// A [Code] object representation of this type annotation.
+  Code get code;
+}
+
+/// The base class for function type declarations.
+abstract class FunctionTypeAnnotation implements TypeAnnotation {
+  /// The return type of this function.
+  TypeAnnotation get returnType;
+
+  /// The positional parameters for this function.
+  Iterable<ParameterDeclaration> get positionalParameters;
+
+  /// The named parameters for this function.
+  Iterable<ParameterDeclaration> get namedParameters;
+
+  /// The type parameters for this function.
+  Iterable<TypeParameterDeclaration> get typeParameters;
+}
+
+/// An unresolved reference to a type.
+///
+/// These can be resolved to a [TypeDeclaration] using the `builder` classes
+/// depending on the phase a macro is running in.
+abstract class NamedTypeAnnotation implements TypeAnnotation {
+  /// The name of the type as it exists in the type annotation.
+  String get name;
+
+  /// The type arguments, if applicable.
+  Iterable<TypeAnnotation> get typeArguments;
+}
+
+/// The interface representing a resolved type.
+///
+/// Resolved types understand exactly what type they represent, and can be
+/// compared to other static types.
+abstract class StaticType {
+  /// Returns true if this is a subtype of [other].
+  Future<bool> isSubtypeOf(StaticType other);
+
+  /// Returns true if this is an identical type to [other].
+  Future<bool> isExactly(StaticType other);
+}
+
+/// A subtype of [StaticType] representing types that can be resolved by name
+/// to a concrete declaration.
+abstract class NamedStaticType implements StaticType {
+  String get name;
+}
+
+/// The base class for all declarations.
+abstract class Declaration {
+  /// The name of this declaration.
+  String get name;
+}
+
+/// A declaration that defines a new type in the program.
+abstract class TypeDeclaration implements Declaration {
+  /// The type parameters defined for this type declaration.
+  Iterable<TypeParameterDeclaration> get typeParameters;
+
+  /// Create a static type representing this type with [typeArguments].
+  ///
+  /// If [isNullable] is `true`, then this type will behave as if it has a
+  /// trailing `?`.
+  ///
+  /// Throws an exception if the type could not be instantiated, typically due
+  /// to one of the type arguments not matching the bounds of the corresponding
+  /// type parameter.
+  Future<StaticType> instantiate(
+      {required List<StaticType> typeArguments, required bool isNullable});
+}
+
+/// Class (and enum) introspection information.
+///
+/// Information about fields, methods, and constructors must be retrieved from
+/// the `builder` objects.
+abstract class ClassDeclaration implements TypeDeclaration {
+  /// Whether this class has an `abstract` modifier.
+  bool get isAbstract;
+
+  /// Whether this class has an `external` modifier.
+  bool get isExternal;
+
+  /// The `extends` type annotation, if present.
+  TypeAnnotation? get superclass;
+
+  /// All the `implements` type annotations.
+  Iterable<TypeAnnotation> get interfaces;
+
+  /// All the `with` type annotations.
+  Iterable<TypeAnnotation> get mixins;
+
+  /// All the type arguments, if applicable.
+  Iterable<TypeParameterDeclaration> get typeParameters;
+}
+
+/// Function introspection information.
+abstract class FunctionDeclaration implements Declaration {
+  /// Whether this function has an `abstract` modifier.
+  bool get isAbstract;
+
+  /// Whether this function has an `external` modifier.
+  bool get isExternal;
+
+  /// Whether this function is actually a getter.
+  bool get isGetter;
+
+  /// Whether this function is actually a setter.
+  bool get isSetter;
+
+  /// The return type of this function.
+  TypeAnnotation get returnType;
+
+  /// The positional parameters for this function.
+  Iterable<ParameterDeclaration> get positionalParameters;
+
+  /// The named parameters for this function.
+  Iterable<ParameterDeclaration> get namedParameters;
+
+  /// The type parameters for this function.
+  Iterable<TypeParameterDeclaration> get typeParameters;
+}
+
+/// Method introspection information.
+abstract class MethodDeclaration implements FunctionDeclaration {
+  /// The class that defines this method.
+  TypeAnnotation get definingClass;
+}
+
+/// Constructor introspection information.
+abstract class ConstructorDeclaration implements MethodDeclaration {
+  /// Whether or not this is a factory constructor.
+  bool get isFactory;
+}
+
+/// Variable introspection information.
+abstract class VariableDeclaration implements Declaration {
+  /// Whether this function has an `abstract` modifier.
+  bool get isAbstract;
+
+  /// Whether this function has an `external` modifier.
+  bool get isExternal;
+
+  /// The type of this field.
+  TypeAnnotation get type;
+
+  /// A [Code] object representing the initializer for this field, if present.
+  Code? get initializer;
+}
+
+/// Field introspection information ..
+abstract class FieldDeclaration implements VariableDeclaration {
+  /// The class that defines this method.
+  TypeAnnotation get definingClass;
+}
+
+/// Parameter introspection information.
+abstract class ParameterDeclaration implements Declaration {
+  /// The type of this parameter.
+  TypeAnnotation get type;
+
+  /// Whether or not this is a named parameter.
+  bool get isNamed;
+
+  /// Whether or not this parameter is either a non-optional positional
+  /// parameter or an optional parameter with the `required` keyword.
+  bool get isRequired;
+
+  /// A [Code] object representing the default value for this parameter, if
+  /// present. Can be used to copy default values to other parameters.
+  Code? get defaultValue;
+}
+
+/// Type parameter introspection information.
+abstract class TypeParameterDeclaration implements Declaration {
+  /// The bounds for this type parameter, if it has any.
+  TypeAnnotation? get bounds;
+}
diff --git a/pkg/_fe_analyzer_shared/lib/src/macros/api/macros.dart b/pkg/_fe_analyzer_shared/lib/src/macros/api/macros.dart
new file mode 100644
index 0000000..7685589a
--- /dev/null
+++ b/pkg/_fe_analyzer_shared/lib/src/macros/api/macros.dart
@@ -0,0 +1,139 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+part of '../api.dart';
+
+/// The marker interface for all types of macros.
+abstract class Macro {}
+
+/// The interface for [Macro]s that can be applied to any top level function,
+/// instance method, or static method, and wants to contribute new type
+/// declarations to the program.
+abstract class FunctionTypesMacro implements Macro {
+  FutureOr<void> buildTypesForFunction(
+      FunctionDeclaration function, TypeBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any top level function,
+/// instance method, or static method, and wants to contribute new non-type
+/// declarations to the program.
+abstract class FunctionDeclarationsMacro implements Macro {
+  FutureOr<void> buildDeclarationsForFunction(
+      FunctionDeclaration function, DeclarationBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any top level function,
+/// instance method, or static method, and wants to augment the function
+/// definition.
+abstract class FunctionDefinitionMacro implements Macro {
+  FutureOr<void> buildDefinitionForFunction(
+      FunctionDeclaration function, FunctionDefinitionBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any top level variable or
+/// instance field, and wants to contribute new type declarations to the
+/// program.
+abstract class VariableTypesMacro implements Macro {
+  FutureOr<void> buildTypesForVariable(
+      VariableDeclaration variable, TypeBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any top level variable or
+/// instance field and wants to contribute new non-type declarations to the
+/// program.
+abstract class VariableDeclarationsMacro implements Macro {
+  FutureOr<void> buildDeclarationsForVariable(
+      VariableDeclaration variable, DeclarationBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any top level variable
+/// or instance field, and wants to augment the variable definition.
+abstract class VariableDefinitionMacro implements Macro {
+  FutureOr<void> buildDefinitionForFunction(
+      VariableDeclaration variable, VariableDefinitionBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any class, and wants to
+/// contribute new type declarations to the program.
+abstract class ClassTypesMacro implements Macro {
+  FutureOr<void> buildTypesForClass(
+      ClassDeclaration clazz, TypeBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any class, and wants to
+/// contribute new non-type declarations to the program.
+abstract class ClassDeclarationsMacro implements Macro {
+  FutureOr<void> buildDeclarationsForClass(
+      ClassDeclaration clazz, ClassDeclarationBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any class, and wants to
+/// augment the definitions of members on the class.
+abstract class ClassDefinitionMacro implements Macro {
+  FutureOr<void> buildDefinitionForClass(
+      ClassDeclaration clazz, ClassDefinitionBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any field, and wants to
+/// contribute new type declarations to the program.
+abstract class FieldTypesMacro implements Macro {
+  FutureOr<void> buildTypesForField(
+      FieldDeclaration field, TypeBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any field, and wants to
+/// contribute new type declarations to the program.
+abstract class FieldDeclarationsMacro implements Macro {
+  FutureOr<void> buildTypesForField(
+      FieldDeclaration field, ClassMemberDeclarationBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any field, and wants to
+/// augment the field definition.
+abstract class FieldDefinitionsMacro implements Macro {
+  FutureOr<void> buildDefinitionForField(
+      FieldDeclaration field, VariableDefinitionBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any method, and wants to
+/// contribute new type declarations to the program.
+abstract class MethodTypesMacro implements Macro {
+  FutureOr<void> buildTypesForMethod(
+      MethodDeclaration method, TypeBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any method, and wants to
+/// contribute new non-type declarations to the program.
+abstract class MethodDeclarationDeclarationsMacro implements Macro {
+  FutureOr<void> buildDeclarationsForMethod(
+      MethodDeclaration method, ClassMemberDeclarationBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any method, and wants to
+/// augment the function definition.
+abstract class MethodDefinitionMacro implements Macro {
+  FutureOr<void> buildDefinitionForMethod(
+      MethodDeclaration method, FunctionDefinitionBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any constructor, and wants
+/// to contribute new type declarations to the program.
+abstract class ConstructorTypesMacro implements Macro {
+  FutureOr<void> buildTypesForConstructor(
+      ConstructorDeclaration method, TypeBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any constructors, and
+/// wants to contribute new non-type declarations to the program.
+abstract class ConstructorDeclarationDeclarationsMacro implements Macro {
+  FutureOr<void> buildDeclarationsForConstructor(
+      ConstructorDeclaration method, ClassMemberDeclarationBuilder builder);
+}
+
+/// The interface for [Macro]s that can be applied to any constructor, and wants
+/// to augment the function definition.
+abstract class ConstructorDefinitionMacro implements Macro {
+  FutureOr<void> buildDefinitionForConstructor(
+      ConstructorDeclaration method, ConstructorDefinitionBuilder builder);
+}
diff --git a/pkg/_fe_analyzer_shared/lib/src/macros/executor.dart b/pkg/_fe_analyzer_shared/lib/src/macros/executor.dart
new file mode 100644
index 0000000..0d4e878
--- /dev/null
+++ b/pkg/_fe_analyzer_shared/lib/src/macros/executor.dart
@@ -0,0 +1,115 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'api.dart';
+
+/// The interface used by Dart language implementations, in order to load
+/// and execute macros, as well as produce library augmentations from those
+/// macro applications.
+///
+/// This class more clearly defines the role of a Dart language implementation
+/// during macro discovery and expansion, and unifies how augmentation libraries
+/// are produced.
+abstract class MacroExecutor {
+  /// Invoked when an implementation discovers a new macro definition in a
+  /// [library] with [name], and prepares this executor to run the macro.
+  ///
+  /// May be invoked more than once for the same macro, which will cause the
+  /// macro to be re-loaded. Previous [MacroClassIdentifier]s and
+  /// [MacroInstanceIdentifier]s given for this macro will be invalid after
+  /// that point and should be discarded.
+  ///
+  /// Throws an exception if the macro fails to load.
+  Future<MacroClassIdentifier> loadMacro(Uri library, String name);
+
+  /// Creates an instance of [macroClass] in the executor, and returns an
+  /// identifier for that instance.
+  ///
+  /// Throws an exception if an instance is not created.
+  Future<MacroInstanceIdentifier> instantiateMacro(
+      MacroClassIdentifier macroClass, String constructor, Arguments arguments);
+
+  /// Runs the type phase for [macro] on a given [declaration].
+  ///
+  /// Throws an exception if there is an error executing the macro.
+  Future<MacroExecutionResult> executeTypesPhase(
+      MacroInstanceIdentifier macro, Declaration declaration);
+
+  /// Runs the declarations phase for [macro] on a given [declaration].
+  ///
+  /// Throws an exception if there is an error executing the macro.
+  Future<MacroExecutionResult> executeDeclarationsPhase(
+      MacroInstanceIdentifier macro,
+      Declaration declaration,
+      TypeResolver typeResolver,
+      ClassIntrospector classIntrospector);
+
+  /// Runs the definitions phase for [macro] on a given [declaration].
+  ///
+  /// Throws an exception if there is an error executing the macro.
+  Future<MacroExecutionResult> executeDefinitionsPhase(
+      MacroInstanceIdentifier macro,
+      Declaration declaration,
+      TypeResolver typeResolver,
+      ClassIntrospector classIntrospector,
+      TypeDeclarationResolver typeDeclarationResolver);
+
+  /// Combines multiple [MacroExecutionResult]s into a single library
+  /// augmentation file, and returns a [String] representing that file.
+  Future<String> buildAugmentationLibrary(
+      Iterable<MacroExecutionResult> macroResults);
+
+  /// Tell the executor to shut down and clean up any resources it may have
+  /// allocated.
+  void close();
+}
+
+/// The arguments passed to a macro constructor.
+///
+/// All argument instances must be of type [Code] or a built-in value type that
+/// is serializable (num, bool, String, null, etc).
+class Arguments {
+  final List<Object?> positional;
+
+  final Map<String, Object?> named;
+
+  Arguments(this.positional, this.named);
+}
+
+/// An opaque identifier for a macro class, retrieved by
+/// [MacroExecutor.loadMacro].
+///
+/// Used to execute or reload this macro in the future.
+abstract class MacroClassIdentifier {}
+
+/// An opaque identifier for an instance of a macro class, retrieved by
+/// [MacroExecutor.instantiateMacro].
+///
+/// Used to execute or reload this macro in the future.
+abstract class MacroInstanceIdentifier {}
+
+/// A summary of the results of running a macro in a given phase.
+///
+/// All modifications are expressed in terms of library augmentation
+/// declarations.
+abstract class MacroExecutionResult {
+  /// Any library imports that should be added to support the code used in
+  /// the augmentations.
+  Iterable<DeclarationCode> get imports;
+
+  /// Any augmentations that should be applied as a result of executing a macro.
+  Iterable<DeclarationCode> get augmentations;
+}
+
+/// Each of the different macro execution phases.
+enum Phase {
+  /// Only new types are added in this phase.
+  types,
+
+  /// New non-type declarations are added in this phase.
+  declarations,
+
+  /// This phase allows augmenting existing declarations.
+  definitions,
+}
diff --git a/pkg/_fe_analyzer_shared/lib/src/macros/isolate_mirrors_executor/isolate_mirrors_executor.dart b/pkg/_fe_analyzer_shared/lib/src/macros/isolate_mirrors_executor/isolate_mirrors_executor.dart
new file mode 100644
index 0000000..d6476af
--- /dev/null
+++ b/pkg/_fe_analyzer_shared/lib/src/macros/isolate_mirrors_executor/isolate_mirrors_executor.dart
@@ -0,0 +1,137 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:async';
+import 'dart:isolate';
+import 'dart:mirrors';
+
+import 'isolate_mirrors_impl.dart';
+import 'protocol.dart';
+import '../executor.dart';
+import '../api.dart';
+
+/// A [MacroExecutor] implementation which relies on [IsolateMirror.loadUri]
+/// in order to load macros libraries.
+///
+/// All actual work happens in a separate [Isolate], and this class serves as
+/// a bridge between that isolate and the language frontends.
+class IsolateMirrorMacroExecutor implements MacroExecutor {
+  /// The actual isolate doing macro loading and execution.
+  final Isolate _macroIsolate;
+
+  /// The channel used to send requests to the [_macroIsolate].
+  final SendPort _sendPort;
+
+  /// The stream of responses from the [_macroIsolate].
+  final Stream<GenericResponse> _responseStream;
+
+  /// A map of response completers by request id.
+  final _responseCompleters = <int, Completer<GenericResponse>>{};
+
+  /// A function that should be invoked when shutting down this executor
+  /// to perform any necessary cleanup.
+  final void Function() _onClose;
+
+  IsolateMirrorMacroExecutor._(
+      this._macroIsolate, this._sendPort, this._responseStream, this._onClose) {
+    _responseStream.listen((event) {
+      Completer<GenericResponse>? completer =
+          _responseCompleters.remove(event.requestId);
+      if (completer == null) {
+        throw new StateError(
+            'Got a response for an unrecognized request id ${event.requestId}');
+      }
+      completer.complete(event);
+    });
+  }
+
+  /// Initialize an [IsolateMirrorMacroExecutor] and return it once ready.
+  ///
+  /// Spawns the macro isolate and sets up a communication channel.
+  static Future<MacroExecutor> start() async {
+    ReceivePort receivePort = new ReceivePort();
+    Completer<SendPort> sendPortCompleter = new Completer<SendPort>();
+    StreamController<GenericResponse> responseStreamController =
+        new StreamController<GenericResponse>(sync: true);
+    receivePort.listen((message) {
+      if (!sendPortCompleter.isCompleted) {
+        sendPortCompleter.complete(message as SendPort);
+      } else {
+        responseStreamController.add(message as GenericResponse);
+      }
+    }).onDone(responseStreamController.close);
+    Isolate macroIsolate = await Isolate.spawn(spawn, receivePort.sendPort);
+
+    return new IsolateMirrorMacroExecutor._(
+        macroIsolate,
+        await sendPortCompleter.future,
+        responseStreamController.stream,
+        receivePort.close);
+  }
+
+  @override
+  Future<String> buildAugmentationLibrary(
+      Iterable<MacroExecutionResult> macroResults) {
+    // TODO: implement buildAugmentationLibrary
+    throw new UnimplementedError();
+  }
+
+  @override
+  void close() {
+    _onClose();
+    _macroIsolate.kill();
+  }
+
+  @override
+  Future<MacroExecutionResult> executeDeclarationsPhase(
+      MacroInstanceIdentifier macro,
+      Declaration declaration,
+      TypeResolver typeResolver,
+      ClassIntrospector classIntrospector) {
+    // TODO: implement executeDeclarationsPhase
+    throw new UnimplementedError();
+  }
+
+  @override
+  Future<MacroExecutionResult> executeDefinitionsPhase(
+          MacroInstanceIdentifier macro,
+          Declaration declaration,
+          TypeResolver typeResolver,
+          ClassIntrospector classIntrospector,
+          TypeDeclarationResolver typeDeclarationResolver) =>
+      _sendRequest(new ExecuteDefinitionsPhaseRequest(macro, declaration,
+          typeResolver, classIntrospector, typeDeclarationResolver));
+
+  @override
+  Future<MacroExecutionResult> executeTypesPhase(
+      MacroInstanceIdentifier macro, Declaration declaration) {
+    // TODO: implement executeTypesPhase
+    throw new UnimplementedError();
+  }
+
+  @override
+  Future<MacroInstanceIdentifier> instantiateMacro(
+          MacroClassIdentifier macroClass,
+          String constructor,
+          Arguments arguments) =>
+      _sendRequest(
+          new InstantiateMacroRequest(macroClass, constructor, arguments));
+
+  @override
+  Future<MacroClassIdentifier> loadMacro(Uri library, String name) =>
+      _sendRequest(new LoadMacroRequest(library, name));
+
+  /// Sends a request and returns the response, casting it to the expected
+  /// type.
+  Future<T> _sendRequest<T>(Request request) async {
+    _sendPort.send(request);
+    Completer<GenericResponse<T>> completer =
+        new Completer<GenericResponse<T>>();
+    _responseCompleters[request.id] = completer;
+    GenericResponse<T> response = await completer.future;
+    T? result = response.response;
+    if (result != null) return result;
+    throw response.error!;
+  }
+}
diff --git a/pkg/_fe_analyzer_shared/lib/src/macros/isolate_mirrors_executor/isolate_mirrors_impl.dart b/pkg/_fe_analyzer_shared/lib/src/macros/isolate_mirrors_executor/isolate_mirrors_impl.dart
new file mode 100644
index 0000000..3cf24a5
--- /dev/null
+++ b/pkg/_fe_analyzer_shared/lib/src/macros/isolate_mirrors_executor/isolate_mirrors_impl.dart
@@ -0,0 +1,255 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:async';
+import 'dart:isolate';
+import 'dart:mirrors';
+
+import 'protocol.dart';
+import '../executor.dart';
+import '../api.dart';
+
+/// Spawns a new isolate for loading and executing macros.
+void spawn(SendPort sendPort) {
+  ReceivePort receivePort = new ReceivePort();
+  sendPort.send(receivePort.sendPort);
+  receivePort.listen((message) async {
+    if (message is LoadMacroRequest) {
+      GenericResponse<MacroClassIdentifier> response =
+          await _loadMacro(message);
+      sendPort.send(response);
+    } else if (message is InstantiateMacroRequest) {
+      GenericResponse<MacroInstanceIdentifier> response =
+          await _instantiateMacro(message);
+      sendPort.send(response);
+    } else if (message is ExecuteDefinitionsPhaseRequest) {
+      GenericResponse<MacroExecutionResult> response =
+          await _executeDefinitionsPhase(message);
+      sendPort.send(response);
+    } else {
+      throw new StateError('Unrecognized event type $message');
+    }
+  });
+}
+
+/// Maps macro identifiers to class mirrors.
+final _macroClasses = <_MacroClassIdentifier, ClassMirror>{};
+
+/// Handles [LoadMacroRequest]s.
+Future<GenericResponse<MacroClassIdentifier>> _loadMacro(
+    LoadMacroRequest request) async {
+  try {
+    _MacroClassIdentifier identifier =
+        new _MacroClassIdentifier(request.library, request.name);
+    if (_macroClasses.containsKey(identifier)) {
+      throw new UnsupportedError(
+          'Reloading macros is not supported by this implementation');
+    }
+    LibraryMirror libMirror =
+        await currentMirrorSystem().isolate.loadUri(request.library);
+    ClassMirror macroClass =
+        libMirror.declarations[new Symbol(request.name)] as ClassMirror;
+    _macroClasses[identifier] = macroClass;
+    return new GenericResponse(response: identifier, requestId: request.id);
+  } catch (e) {
+    return new GenericResponse(error: e, requestId: request.id);
+  }
+}
+
+/// Maps macro instance identifiers to instances.
+final _macroInstances = <_MacroInstanceIdentifier, Macro>{};
+
+/// Handles [InstantiateMacroRequest]s.
+Future<GenericResponse<MacroInstanceIdentifier>> _instantiateMacro(
+    InstantiateMacroRequest request) async {
+  try {
+    ClassMirror? clazz = _macroClasses[request.macroClass];
+    if (clazz == null) {
+      throw new ArgumentError('Unrecognized macro class ${request.macroClass}');
+    }
+    Macro instance = clazz.newInstance(
+        new Symbol(request.constructorName), request.arguments.positional, {
+      for (MapEntry<String, Object?> entry in request.arguments.named.entries)
+        new Symbol(entry.key): entry.value,
+    }).reflectee as Macro;
+    _MacroInstanceIdentifier identifier = new _MacroInstanceIdentifier();
+    _macroInstances[identifier] = instance;
+    return new GenericResponse<MacroInstanceIdentifier>(
+        response: identifier, requestId: request.id);
+  } catch (e) {
+    return new GenericResponse(error: e, requestId: request.id);
+  }
+}
+
+Future<GenericResponse<MacroExecutionResult>> _executeDefinitionsPhase(
+    ExecuteDefinitionsPhaseRequest request) async {
+  try {
+    Macro? instance = _macroInstances[request.macro];
+    if (instance == null) {
+      throw new StateError('Unrecognized macro instance ${request.macro}\n'
+          'Known instances: $_macroInstances)');
+    }
+    Declaration declaration = request.declaration;
+    if (instance is FunctionDefinitionMacro &&
+        declaration is FunctionDeclaration) {
+      _FunctionDefinitionBuilder builder = new _FunctionDefinitionBuilder(
+          declaration,
+          request.typeResolver,
+          request.typeDeclarationResolver,
+          request.classIntrospector);
+      await instance.buildDefinitionForFunction(declaration, builder);
+      return new GenericResponse(
+          response: builder.result, requestId: request.id);
+    } else {
+      throw new UnsupportedError(
+          ('Only FunctionDefinitionMacros are supported currently'));
+    }
+  } catch (e) {
+    return new GenericResponse(error: e, requestId: request.id);
+  }
+}
+
+/// Our implementation of [MacroClassIdentifier].
+class _MacroClassIdentifier implements MacroClassIdentifier {
+  final String id;
+
+  _MacroClassIdentifier(Uri library, String name) : id = '$library#$name';
+
+  operator ==(other) => other is _MacroClassIdentifier && id == other.id;
+
+  int get hashCode => id.hashCode;
+}
+
+/// Our implementation of [MacroInstanceIdentifier].
+class _MacroInstanceIdentifier implements MacroInstanceIdentifier {
+  static int _next = 0;
+
+  final int id;
+
+  _MacroInstanceIdentifier() : id = _next++;
+
+  operator ==(other) => other is _MacroInstanceIdentifier && id == other.id;
+
+  int get hashCode => id;
+}
+
+/// Our implementation of [MacroExecutionResult].
+class _MacroExecutionResult implements MacroExecutionResult {
+  @override
+  final List<DeclarationCode> augmentations = <DeclarationCode>[];
+
+  @override
+  final List<DeclarationCode> imports = <DeclarationCode>[];
+}
+
+/// Custom implementation of [FunctionDefinitionBuilder].
+class _FunctionDefinitionBuilder implements FunctionDefinitionBuilder {
+  final TypeResolver typeResolver;
+  final TypeDeclarationResolver typeDeclarationResolver;
+  final ClassIntrospector classIntrospector;
+
+  /// The declaration this is a builder for.
+  final FunctionDeclaration declaration;
+
+  /// The final result, will be built up over `augment` calls.
+  final _MacroExecutionResult result = new _MacroExecutionResult();
+
+  _FunctionDefinitionBuilder(this.declaration, this.typeResolver,
+      this.typeDeclarationResolver, this.classIntrospector);
+
+  @override
+  void augment(FunctionBodyCode body) {
+    result.augmentations.add(new DeclarationCode.fromParts([
+      'augment ',
+      declaration.returnType.code,
+      ' ',
+      declaration.name,
+      if (declaration.typeParameters.isNotEmpty) ...[
+        '<',
+        for (TypeParameterDeclaration typeParam
+            in declaration.typeParameters) ...[
+          typeParam.name,
+          if (typeParam.bounds != null) ...['extends ', typeParam.bounds!.code],
+          if (typeParam != declaration.typeParameters.last) ', ',
+        ],
+        '>',
+      ],
+      '(',
+      for (ParameterDeclaration positionalRequired
+          in declaration.positionalParameters.where((p) => p.isRequired)) ...[
+        new ParameterCode.fromParts([
+          positionalRequired.type.code,
+          ' ',
+          positionalRequired.name,
+        ]),
+        ', '
+      ],
+      if (declaration.positionalParameters.any((p) => !p.isRequired)) ...[
+        '[',
+        for (ParameterDeclaration positionalOptional in declaration
+            .positionalParameters
+            .where((p) => !p.isRequired)) ...[
+          new ParameterCode.fromParts([
+            positionalOptional.type.code,
+            ' ',
+            positionalOptional.name,
+          ]),
+          ', ',
+        ],
+        ']',
+      ],
+      if (declaration.namedParameters.isNotEmpty) ...[
+        '{',
+        for (ParameterDeclaration named in declaration.namedParameters) ...[
+          new ParameterCode.fromParts([
+            if (named.isRequired) 'required ',
+            named.type.code,
+            ' ',
+            named.name,
+            if (named.defaultValue != null) ...[
+              ' = ',
+              named.defaultValue!,
+            ],
+          ]),
+          ', ',
+        ],
+        '}',
+      ],
+      ') ',
+      body,
+    ]));
+  }
+
+  @override
+  Future<List<ConstructorDeclaration>> constructorsOf(ClassDeclaration clazz) =>
+      classIntrospector.constructorsOf(clazz);
+
+  @override
+  Future<List<FieldDeclaration>> fieldsOf(ClassDeclaration clazz) =>
+      classIntrospector.fieldsOf(clazz);
+
+  @override
+  Future<List<ClassDeclaration>> interfacesOf(ClassDeclaration clazz) =>
+      classIntrospector.interfacesOf(clazz);
+
+  @override
+  Future<List<MethodDeclaration>> methodsOf(ClassDeclaration clazz) =>
+      classIntrospector.methodsOf(clazz);
+
+  @override
+  Future<List<ClassDeclaration>> mixinsOf(ClassDeclaration clazz) =>
+      classIntrospector.mixinsOf(clazz);
+
+  @override
+  Future<TypeDeclaration> declarationOf(NamedStaticType annotation) =>
+      typeDeclarationResolver.declarationOf(annotation);
+
+  @override
+  Future<ClassDeclaration?> superclassOf(ClassDeclaration clazz) =>
+      classIntrospector.superclassOf(clazz);
+
+  @override
+  Future<StaticType> resolve(TypeAnnotation typeAnnotation) =>
+      typeResolver.resolve(typeAnnotation);
+}
diff --git a/pkg/_fe_analyzer_shared/lib/src/macros/isolate_mirrors_executor/protocol.dart b/pkg/_fe_analyzer_shared/lib/src/macros/isolate_mirrors_executor/protocol.dart
new file mode 100644
index 0000000..96a2724
--- /dev/null
+++ b/pkg/_fe_analyzer_shared/lib/src/macros/isolate_mirrors_executor/protocol.dart
@@ -0,0 +1,61 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+/// Defines the objects used for communication between the macro executor and
+/// the isolate doing the work of macro loading and execution.
+library protocol;
+
+import '../executor.dart';
+import '../api.dart';
+
+/// Base class all requests extend, provides a unique id for each request.
+class Request {
+  final int id;
+
+  Request() : id = _next++;
+
+  static int _next = 0;
+}
+
+/// A generic response object that is either an instance of [T] or an error.
+class GenericResponse<T> {
+  final T? response;
+  final Object? error;
+  final int requestId;
+
+  GenericResponse({this.response, this.error, required this.requestId})
+      : assert(response != null || error != null),
+        assert(response == null || error == null);
+}
+
+/// A request to load a macro in this isolate.
+class LoadMacroRequest extends Request {
+  final Uri library;
+  final String name;
+
+  LoadMacroRequest(this.library, this.name);
+}
+
+/// A request to instantiate a macro instance.
+class InstantiateMacroRequest extends Request {
+  final MacroClassIdentifier macroClass;
+  final String constructorName;
+  final Arguments arguments;
+
+  InstantiateMacroRequest(
+      this.macroClass, this.constructorName, this.arguments);
+}
+
+/// A request to execute a macro on a particular declaration in the definition
+/// phase.
+class ExecuteDefinitionsPhaseRequest extends Request {
+  final MacroInstanceIdentifier macro;
+  final Declaration declaration;
+  final TypeResolver typeResolver;
+  final ClassIntrospector classIntrospector;
+  final TypeDeclarationResolver typeDeclarationResolver;
+
+  ExecuteDefinitionsPhaseRequest(this.macro, this.declaration,
+      this.typeResolver, this.classIntrospector, this.typeDeclarationResolver);
+}
diff --git a/pkg/_fe_analyzer_shared/lib/src/messages/codes_generated.dart b/pkg/_fe_analyzer_shared/lib/src/messages/codes_generated.dart
index 7cfb915..14682ea 100644
--- a/pkg/_fe_analyzer_shared/lib/src/messages/codes_generated.dart
+++ b/pkg/_fe_analyzer_shared/lib/src/messages/codes_generated.dart
@@ -3836,6 +3836,26 @@
   -h        Display this message (add -v for information about all options).""");
 
 // DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
+const Code<Null> codeFfiAbiSpecificIntegerInvalid =
+    messageFfiAbiSpecificIntegerInvalid;
+
+// DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
+const MessageCode messageFfiAbiSpecificIntegerInvalid = const MessageCode(
+    "FfiAbiSpecificIntegerInvalid",
+    problemMessage:
+        r"""Classes extending 'AbiSpecificInteger' must have exactly one const constructor, no other members, and no type arguments.""");
+
+// DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
+const Code<Null> codeFfiAbiSpecificIntegerMappingInvalid =
+    messageFfiAbiSpecificIntegerMappingInvalid;
+
+// DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
+const MessageCode messageFfiAbiSpecificIntegerMappingInvalid = const MessageCode(
+    "FfiAbiSpecificIntegerMappingInvalid",
+    problemMessage:
+        r"""Classes extending 'AbiSpecificInteger' must have exactly one 'AbiSpecificIntegerMapping' annotation specifying the mapping from ABI to a NativeType integer with a fixed size.""");
+
+// DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
 const Template<
     Message Function(
         String string,
@@ -8810,6 +8830,16 @@
     correctionMessage: r"""Try replacing ':' with '='.""");
 
 // DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
+const Code<Null> codePositionalSuperParametersAndArguments =
+    messagePositionalSuperParametersAndArguments;
+
+// DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
+const MessageCode messagePositionalSuperParametersAndArguments = const MessageCode(
+    "PositionalSuperParametersAndArguments",
+    problemMessage:
+        r"""Positional super-initializer parameters cannot be used when the super initializer has positional arguments.""");
+
+// DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
 const Code<Null> codePrefixAfterCombinator = messagePrefixAfterCombinator;
 
 // DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
@@ -9412,6 +9442,16 @@
     problemMessage: r"""Can't have initializers after 'super'.""");
 
 // DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
+const Code<Null> codeSuperInitializerParameter =
+    messageSuperInitializerParameter;
+
+// DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
+const MessageCode messageSuperInitializerParameter = const MessageCode(
+    "SuperInitializerParameter",
+    severity: Severity.context,
+    problemMessage: r"""This is the super-initializer parameter.""");
+
+// DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
 const Code<Null> codeSuperNullAware = messageSuperNullAware;
 
 // DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
diff --git a/pkg/_fe_analyzer_shared/lib/src/parser/forwarding_listener.dart b/pkg/_fe_analyzer_shared/lib/src/parser/forwarding_listener.dart
index c60aa80..9741d8c 100644
--- a/pkg/_fe_analyzer_shared/lib/src/parser/forwarding_listener.dart
+++ b/pkg/_fe_analyzer_shared/lib/src/parser/forwarding_listener.dart
@@ -61,8 +61,9 @@
   }
 
   @override
-  void beginClassDeclaration(Token begin, Token? abstractToken, Token name) {
-    listener?.beginClassDeclaration(begin, abstractToken, name);
+  void beginClassDeclaration(
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {
+    listener?.beginClassDeclaration(begin, abstractToken, macroToken, name);
   }
 
   @override
@@ -339,8 +340,9 @@
 
   @override
   void beginNamedMixinApplication(
-      Token begin, Token? abstractToken, Token name) {
-    listener?.beginNamedMixinApplication(begin, abstractToken, name);
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {
+    listener?.beginNamedMixinApplication(
+        begin, abstractToken, macroToken, name);
   }
 
   @override
@@ -1259,8 +1261,14 @@
 
   @override
   void handleCommentReference(
-      Token? newKeyword, Token? prefix, Token? period, Token token) {
-    listener?.handleCommentReference(newKeyword, prefix, period, token);
+      Token? newKeyword,
+      Token? firstToken,
+      Token? firstPeriod,
+      Token? secondToken,
+      Token? secondPeriod,
+      Token thirdToken) {
+    listener?.handleCommentReference(newKeyword, firstToken, firstPeriod,
+        secondToken, secondPeriod, thirdToken);
   }
 
   @override
diff --git a/pkg/_fe_analyzer_shared/lib/src/parser/listener.dart b/pkg/_fe_analyzer_shared/lib/src/parser/listener.dart
index 332225f..2f5e2a4 100644
--- a/pkg/_fe_analyzer_shared/lib/src/parser/listener.dart
+++ b/pkg/_fe_analyzer_shared/lib/src/parser/listener.dart
@@ -126,7 +126,8 @@
   /// (or extraneous modifiers in the case of recovery) preceding [name].
   ///
   /// At this point we have parsed the name and type parameter declarations.
-  void beginClassDeclaration(Token begin, Token? abstractToken, Token name) {}
+  void beginClassDeclaration(
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {}
 
   /// Handle an extends clause in a class declaration. Substructures:
   /// - supertype (may be a mixin application)
@@ -720,7 +721,7 @@
   ///
   /// At this point we have parsed the name and type parameter declarations.
   void beginNamedMixinApplication(
-      Token begin, Token? abstractToken, Token name) {}
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {}
 
   /// Handle a named mixin application with clause (e.g. "A with B, C").
   /// Substructures:
@@ -1840,13 +1841,20 @@
 
   /// A single comment reference has been parsed.
   /// * [newKeyword] may be null.
-  /// * [prefix] and [period] are either both tokens or both `null`.
-  /// * [token] can be an identifier or an operator.
+  /// * [firstToken] and [firstPeriod] are either both tokens or both
+  ///   `null`.
+  /// * [secondToken] and [secondPeriod] are either both tokens or both `null`.
+  /// * [thirdToken] can be an identifier or an operator.
   ///
   /// This event is generated by the parser when the parser's
   /// `parseOneCommentReference` method is called.
   void handleCommentReference(
-      Token? newKeyword, Token? prefix, Token? period, Token token) {}
+      Token? newKeyword,
+      Token? firstToken,
+      Token? firstPeriod,
+      Token? secondToken,
+      Token? secondPeriod,
+      Token thirdToken) {}
 
   /// This event is generated by the parser when the parser's
   /// `parseOneCommentReference` method is called.
diff --git a/pkg/_fe_analyzer_shared/lib/src/parser/parser_impl.dart b/pkg/_fe_analyzer_shared/lib/src/parser/parser_impl.dart
index fac9391..43e8331 100644
--- a/pkg/_fe_analyzer_shared/lib/src/parser/parser_impl.dart
+++ b/pkg/_fe_analyzer_shared/lib/src/parser/parser_impl.dart
@@ -494,7 +494,8 @@
     token = parseMetadataStar(token);
     Token next = token.next!;
     if (next.isTopLevelKeyword) {
-      return parseTopLevelKeywordDeclaration(token, next, directiveState);
+      return parseTopLevelKeywordDeclaration(/* start = */ token,
+          /* keyword = */ next, /* macroToken = */ null, directiveState);
     }
     Token start = token;
     // Skip modifiers to find a top level keyword or identifier
@@ -513,8 +514,16 @@
       }
     }
     next = token.next!;
+    Token? macroToken;
+    if (next.isIdentifier &&
+        next.lexeme == 'macro' &&
+        optional('class', next.next!)) {
+      macroToken = next;
+      next = next.next!;
+    }
     if (next.isTopLevelKeyword) {
-      return parseTopLevelKeywordDeclaration(start, next, directiveState);
+      return parseTopLevelKeywordDeclaration(/* start = */ start,
+          /* keyword = */ next, /* macroToken = */ macroToken, directiveState);
     } else if (next.isKeywordOrIdentifier) {
       // TODO(danrubel): improve parseTopLevelMember
       // so that we don't parse modifiers twice.
@@ -591,14 +600,16 @@
 
   /// Parse any top-level declaration that begins with a keyword.
   /// [start] is the token before any modifiers preceding [keyword].
-  Token parseTopLevelKeywordDeclaration(
-      Token start, Token keyword, DirectiveContext? directiveState) {
+  Token parseTopLevelKeywordDeclaration(Token start, Token keyword,
+      Token? macroToken, DirectiveContext? directiveState) {
     assert(keyword.isTopLevelKeyword);
     final String? value = keyword.stringValue;
     if (identical(value, 'class')) {
       directiveState?.checkDeclaration();
-      Token? abstractToken = parseClassDeclarationModifiers(start, keyword);
-      return parseClassOrNamedMixinApplication(abstractToken, keyword);
+      Token? abstractToken =
+          parseClassDeclarationModifiers(start, macroToken ?? keyword);
+      return parseClassOrNamedMixinApplication(
+          abstractToken, macroToken, keyword);
     } else if (identical(value, 'enum')) {
       directiveState?.checkDeclaration();
       parseTopLevelKeywordModifiers(start, keyword);
@@ -2055,7 +2066,7 @@
   }
 
   Token parseClassOrNamedMixinApplication(
-      Token? abstractToken, Token classKeyword) {
+      Token? abstractToken, Token? macroToken, Token classKeyword) {
     assert(optional('class', classKeyword));
     Token begin = abstractToken ?? classKeyword;
     listener.beginClassOrMixinOrNamedMixinApplicationPrelude(begin);
@@ -2065,10 +2076,11 @@
             name, /* inDeclaration = */ true, /* allowsVariance = */ true)
         .parseVariables(name, this);
     if (optional('=', token.next!)) {
-      listener.beginNamedMixinApplication(begin, abstractToken, name);
+      listener.beginNamedMixinApplication(
+          begin, abstractToken, macroToken, name);
       return parseNamedMixinApplication(token, begin, classKeyword);
     } else {
-      listener.beginClassDeclaration(begin, abstractToken, name);
+      listener.beginClassDeclaration(begin, abstractToken, macroToken, name);
       return parseClass(token, begin, classKeyword, name.lexeme);
     }
   }
@@ -8355,26 +8367,33 @@
       newKeyword = token;
       token = token.next!;
     }
-    Token? prefix, period;
+    Token? firstToken, firstPeriod, secondToken, secondPeriod;
     if (token.isIdentifier && optional('.', token.next!)) {
-      prefix = token;
-      period = token.next!;
-      Token identifier = period.next!;
+      secondToken = token;
+      secondPeriod = token.next!;
+      if (secondPeriod.next!.isIdentifier &&
+          optional('.', secondPeriod.next!.next!)) {
+        firstToken = secondToken;
+        firstPeriod = secondPeriod;
+        secondToken = secondPeriod.next!;
+        secondPeriod = secondToken.next!;
+      }
+      Token identifier = secondPeriod.next!;
       if (identifier.kind == KEYWORD_TOKEN && optional('new', identifier)) {
         // Treat `new` after `.` is as an identifier so that it can represent an
         // unnamed constructor. This support is separate from the
         // constructor-tearoffs feature.
         rewriter.replaceTokenFollowing(
-            period,
+            secondPeriod,
             new StringToken(TokenType.IDENTIFIER, identifier.lexeme,
                 identifier.charOffset));
       }
-      token = period.next!;
+      token = secondPeriod.next!;
     }
     if (token.isEof) {
       // Recovery: Insert a synthetic identifier for code completion
       token = rewriter.insertSyntheticIdentifier(
-          period ?? newKeyword ?? syntheticPreviousToken(token));
+          secondPeriod ?? newKeyword ?? syntheticPreviousToken(token));
       if (begin == token.next!) {
         begin = token;
       }
@@ -8386,21 +8405,21 @@
     }
     if (token.isUserDefinableOperator) {
       if (token.next!.isEof) {
-        parseOneCommentReferenceRest(
-            begin, referenceOffset, newKeyword, prefix, period, token);
+        parseOneCommentReferenceRest(begin, referenceOffset, newKeyword,
+            firstToken, firstPeriod, secondToken, secondPeriod, token);
         return true;
       }
     } else {
       token = operatorKeyword ?? token;
       if (token.next!.isEof) {
         if (token.isIdentifier) {
-          parseOneCommentReferenceRest(
-              begin, referenceOffset, newKeyword, prefix, period, token);
+          parseOneCommentReferenceRest(begin, referenceOffset, newKeyword,
+              firstToken, firstPeriod, secondToken, secondPeriod, token);
           return true;
         }
         Keyword? keyword = token.keyword;
         if (newKeyword == null &&
-            prefix == null &&
+            secondToken == null &&
             (keyword == Keyword.THIS ||
                 keyword == Keyword.NULL ||
                 keyword == Keyword.TRUE ||
@@ -8421,8 +8440,10 @@
       Token begin,
       int referenceOffset,
       Token? newKeyword,
-      Token? prefix,
-      Token? period,
+      Token? firstToken,
+      Token? firstPeriod,
+      Token? secondToken,
+      Token? secondPeriod,
       Token identifierOrOperator) {
     // Adjust the token offsets to match the enclosing comment token.
     Token token = begin;
@@ -8431,8 +8452,8 @@
       token = token.next!;
     } while (!token.isEof);
 
-    listener.handleCommentReference(
-        newKeyword, prefix, period, identifierOrOperator);
+    listener.handleCommentReference(newKeyword, firstToken, firstPeriod,
+        secondToken, secondPeriod, identifierOrOperator);
   }
 
   /// Given that we have just found bracketed text within the given [comment],
diff --git a/pkg/_fe_analyzer_shared/pubspec.yaml b/pkg/_fe_analyzer_shared/pubspec.yaml
index 445f314..9b35add 100644
--- a/pkg/_fe_analyzer_shared/pubspec.yaml
+++ b/pkg/_fe_analyzer_shared/pubspec.yaml
@@ -1,5 +1,5 @@
 name: _fe_analyzer_shared
-version: 31.0.0
+version: 32.0.0
 description: Logic that is shared between the front_end and analyzer packages.
 homepage: https://github.com/dart-lang/sdk/tree/master/pkg/_fe_analyzer_shared
 
diff --git a/pkg/_fe_analyzer_shared/test/macros/isolate_mirror_executor/isolate_mirror_executor_test.dart b/pkg/_fe_analyzer_shared/test/macros/isolate_mirror_executor/isolate_mirror_executor_test.dart
new file mode 100644
index 0000000..48ca97b
--- /dev/null
+++ b/pkg/_fe_analyzer_shared/test/macros/isolate_mirror_executor/isolate_mirror_executor_test.dart
@@ -0,0 +1,147 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:io';
+
+import 'package:_fe_analyzer_shared/src/macros/api.dart';
+import 'package:_fe_analyzer_shared/src/macros/executor.dart';
+import 'package:_fe_analyzer_shared/src/macros/isolate_mirrors_executor/isolate_mirrors_executor.dart';
+
+import 'package:test/fake.dart';
+import 'package:test/test.dart';
+
+void main() {
+  late MacroExecutor executor;
+
+  setUp(() async {
+    executor = await IsolateMirrorMacroExecutor.start();
+  });
+
+  tearDown(() {
+    executor.close();
+  });
+
+  test('can load macros and create instances', () async {
+    var clazzId = await executor.loadMacro(
+        // Tests run from the root of the repo.
+        File('pkg/_fe_analyzer_shared/test/macros/isolate_mirror_executor/simple_macro.dart')
+            .absolute
+            .uri,
+        'SimpleMacro');
+    expect(clazzId, isNotNull, reason: 'Can load a macro.');
+
+    var instanceId =
+        await executor.instantiateMacro(clazzId, '', Arguments([], {}));
+    expect(instanceId, isNotNull,
+        reason: 'Can create an instance with no arguments.');
+
+    instanceId =
+        await executor.instantiateMacro(clazzId, '', Arguments([1, 2], {}));
+    expect(instanceId, isNotNull,
+        reason: 'Can create an instance with positional arguments.');
+
+    instanceId = await executor.instantiateMacro(
+        clazzId, 'named', Arguments([], {'x': 1, 'y': 2}));
+    expect(instanceId, isNotNull,
+        reason: 'Can create an instance with named arguments.');
+
+    var definitionResult = await executor.executeDefinitionsPhase(
+        instanceId,
+        _FunctionDeclaration(
+          isAbstract: false,
+          isExternal: false,
+          isGetter: false,
+          isSetter: false,
+          name: 'foo',
+          namedParameters: [],
+          positionalParameters: [],
+          returnType:
+              _TypeAnnotation(Code.fromString('String'), isNullable: false),
+          typeParameters: [],
+        ),
+        _FakeTypeResolver(),
+        _FakeClassIntrospector(),
+        _FakeTypeDeclarationResolver());
+    expect(definitionResult.augmentations, hasLength(1));
+    expect(definitionResult.augmentations.first.debugString().toString(),
+        equalsIgnoringWhitespace('''
+            augment String foo() {
+              print('x: 1, y: 2');
+              return augment super();
+            }'''));
+  });
+}
+
+class _FakeClassIntrospector with Fake implements ClassIntrospector {}
+
+class _FakeTypeResolver with Fake implements TypeResolver {}
+
+class _FakeTypeDeclarationResolver
+    with Fake
+    implements TypeDeclarationResolver {}
+
+class _FunctionDeclaration implements FunctionDeclaration {
+  @override
+  final bool isAbstract;
+
+  @override
+  final bool isExternal;
+
+  @override
+  final bool isGetter;
+
+  @override
+  final bool isSetter;
+
+  @override
+  final String name;
+
+  @override
+  final Iterable<ParameterDeclaration> namedParameters;
+
+  @override
+  final Iterable<ParameterDeclaration> positionalParameters;
+
+  @override
+  final TypeAnnotation returnType;
+
+  @override
+  final Iterable<TypeParameterDeclaration> typeParameters;
+
+  _FunctionDeclaration({
+    required this.isAbstract,
+    required this.isExternal,
+    required this.isGetter,
+    required this.isSetter,
+    required this.name,
+    required this.namedParameters,
+    required this.positionalParameters,
+    required this.returnType,
+    required this.typeParameters,
+  });
+}
+
+class _TypeAnnotation implements TypeAnnotation {
+  @override
+  final Code code;
+
+  @override
+  final bool isNullable;
+
+  _TypeAnnotation(this.code, {required this.isNullable});
+}
+
+extension _ on Code {
+  StringBuffer debugString([StringBuffer? buffer]) {
+    buffer ??= StringBuffer();
+    for (var part in parts) {
+      if (part is Code) {
+        part.debugString(buffer);
+      } else {
+        buffer.write(part.toString());
+      }
+    }
+    return buffer;
+  }
+}
diff --git a/pkg/_fe_analyzer_shared/test/macros/isolate_mirror_executor/simple_macro.dart b/pkg/_fe_analyzer_shared/test/macros/isolate_mirror_executor/simple_macro.dart
new file mode 100644
index 0000000..b95da0b
--- /dev/null
+++ b/pkg/_fe_analyzer_shared/test/macros/isolate_mirror_executor/simple_macro.dart
@@ -0,0 +1,33 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:async';
+
+import 'package:_fe_analyzer_shared/src/macros/api.dart';
+
+/// A very simple macro that annotates functions (or getters) with no arguments
+/// and adds a print statement to the top of them.
+class SimpleMacro implements FunctionDefinitionMacro {
+  final int? x;
+  final int? y;
+
+  SimpleMacro([this.x, this.y]);
+
+  SimpleMacro.named({this.x, this.y});
+
+  @override
+  FutureOr<void> buildDefinitionForFunction(
+      FunctionDeclaration method, FunctionDefinitionBuilder builder) {
+    if (method.namedParameters
+        .followedBy(method.positionalParameters)
+        .isNotEmpty) {
+      throw ArgumentError(
+          'This macro can only be run on functions with no arguments!');
+    }
+    builder.augment(FunctionBodyCode.fromString('''{
+      print('x: $x, y: $y');
+      return augment super();
+    }'''));
+  }
+}
diff --git a/pkg/_js_interop_checks/lib/js_interop_checks.dart b/pkg/_js_interop_checks/lib/js_interop_checks.dart
index 24937db..e9f6fb0 100644
--- a/pkg/_js_interop_checks/lib/js_interop_checks.dart
+++ b/pkg/_js_interop_checks/lib/js_interop_checks.dart
@@ -252,7 +252,8 @@
 
     if (_classHasStaticInteropAnnotation &&
         procedure.isInstanceMember &&
-        !procedure.isFactory) {
+        !procedure.isFactory &&
+        !procedure.isSynthetic) {
       _diagnosticsReporter.report(
           templateJsInteropStaticInteropWithInstanceMembers
               .withArguments(procedure.enclosingClass!.name),
diff --git a/pkg/_js_interop_checks/lib/src/transformations/static_interop_class_eraser.dart b/pkg/_js_interop_checks/lib/src/transformations/static_interop_class_eraser.dart
new file mode 100644
index 0000000..e00c88e
--- /dev/null
+++ b/pkg/_js_interop_checks/lib/src/transformations/static_interop_class_eraser.dart
@@ -0,0 +1,183 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:kernel/ast.dart';
+import 'package:kernel/clone.dart';
+import 'package:kernel/core_types.dart';
+import 'package:kernel/kernel.dart';
+import 'package:kernel/src/replacement_visitor.dart';
+import 'package:_js_interop_checks/src/js_interop.dart';
+
+class _TypeSubstitutor extends ReplacementVisitor {
+  final Class _javaScriptObject;
+  _TypeSubstitutor(this._javaScriptObject);
+
+  @override
+  DartType? visitInterfaceType(InterfaceType type, int variance) {
+    if (hasStaticInteropAnnotation(type.classNode)) {
+      return InterfaceType(_javaScriptObject, type.declaredNullability);
+    }
+    return super.visitInterfaceType(type, variance);
+  }
+}
+
+/// Erases usage of `@JS` classes that are annotated with `@staticInterop` in
+/// favor of `JavaScriptObject`.
+class StaticInteropClassEraser extends Transformer {
+  final Class _javaScriptObject;
+  final CloneVisitorNotMembers _cloner = CloneVisitorNotMembers();
+  late final _TypeSubstitutor _typeSubstitutor;
+
+  StaticInteropClassEraser(CoreTypes coreTypes)
+      : _javaScriptObject =
+            coreTypes.index.getClass('dart:_interceptors', 'JavaScriptObject') {
+    _typeSubstitutor = _TypeSubstitutor(_javaScriptObject);
+  }
+
+  String _factoryStubName(Procedure factoryTarget) =>
+      '${factoryTarget.name}|staticInteropFactoryStub';
+
+  /// Either finds or creates a static method stub to replace factories with a
+  /// body in a static interop class.
+  ///
+  /// Modifies [factoryTarget]'s enclosing class to include the new method.
+  Procedure _findOrCreateFactoryStub(Procedure factoryTarget) {
+    assert(factoryTarget.isFactory);
+    var factoryClass = factoryTarget.enclosingClass!;
+    assert(hasStaticInteropAnnotation(factoryClass));
+    var stubName = _factoryStubName(factoryTarget);
+    var stubs = factoryClass.procedures
+        .where((procedure) => procedure.name.text == stubName);
+    if (stubs.isEmpty) {
+      // Note that the return type of the cloned function is transformed.
+      var functionNode =
+          super.visitFunctionNode(_cloner.clone(factoryTarget.function))
+              as FunctionNode;
+      var staticMethod = Procedure(
+          Name(stubName), ProcedureKind.Method, functionNode,
+          isStatic: true, fileUri: factoryTarget.fileUri)
+        ..parent = factoryClass;
+      factoryClass.procedures.add(staticMethod);
+      return staticMethod;
+    } else {
+      assert(stubs.length == 1);
+      return stubs.first;
+    }
+  }
+
+  @override
+  TreeNode visitConstructor(Constructor node) {
+    if (hasStaticInteropAnnotation(node.enclosingClass)) {
+      // Transform children of the constructor node excluding the return type.
+      var returnType = node.function.returnType;
+      var newConstructor = super.visitConstructor(node) as Constructor;
+      newConstructor.function.returnType = returnType;
+      return newConstructor;
+    }
+    return super.visitConstructor(node);
+  }
+
+  @override
+  TreeNode visitProcedure(Procedure node) {
+    // Avoid changing the return types of factories, but rather cast the type of
+    // the invocation.
+    if (node.isFactory && hasStaticInteropAnnotation(node.enclosingClass!)) {
+      if (node.function.body != null && !node.isRedirectingFactory) {
+        // Bodies of factories may undergo transformation, which may result in
+        // type invariants breaking. For a motivating example, consider:
+        //
+        // ```
+        // factory Foo.fact() => Foo.cons();
+        // ```
+        //
+        // The invocation of `cons` would have its type erased, but then it
+        // would no longer match the return type of `fact`, whose return type
+        // shouldn't get erased as it is a factory. Note that this is only an
+        // issue when the factory has a body that doesn't simply redirect.
+        //
+        // In order to circumvent this, we introduce a new static method that
+        // clones the factory body and has a return type of
+        // `JavaScriptObject`. Invocations of the factory are turned into
+        // invocations of the static method. The original factory is still kept
+        // in order to make modular compilations work.
+        _findOrCreateFactoryStub(node);
+        return node;
+      } else {
+        // Transform children of the factory node excluding the return type and
+        // return type of the signature type.
+        var returnType = node.function.returnType;
+        var signatureReturnType = node.signatureType?.returnType;
+        var newProcedure = super.visitProcedure(node) as Procedure;
+        newProcedure.function.returnType = returnType;
+        var signatureType = newProcedure.signatureType;
+        if (signatureType != null && signatureReturnType != null) {
+          newProcedure.signatureType = FunctionType(
+              signatureType.positionalParameters,
+              signatureReturnType,
+              signatureType.declaredNullability,
+              namedParameters: signatureType.namedParameters,
+              typeParameters: signatureType.typeParameters,
+              requiredParameterCount: signatureType.requiredParameterCount,
+              typedefType: signatureType.typedefType);
+        }
+        return newProcedure;
+      }
+    }
+    return super.visitProcedure(node);
+  }
+
+  @override
+  TreeNode visitConstructorInvocation(ConstructorInvocation node) {
+    if (hasStaticInteropAnnotation(node.target.enclosingClass)) {
+      // Add a cast so that the result gets typed as `JavaScriptObject`.
+      var newInvocation = super.visitConstructorInvocation(node) as Expression;
+      return AsExpression(
+          newInvocation,
+          InterfaceType(_javaScriptObject,
+              node.target.function.returnType.declaredNullability))
+        ..fileOffset = newInvocation.fileOffset;
+    }
+    return super.visitConstructorInvocation(node);
+  }
+
+  /// Transform static invocations that correspond only to factories of static
+  /// interop classes.
+  @override
+  TreeNode visitStaticInvocation(StaticInvocation node) {
+    var targetClass = node.target.enclosingClass;
+    if (node.target.isFactory &&
+        targetClass != null &&
+        hasStaticInteropAnnotation(targetClass)) {
+      var factoryTarget = node.target;
+      if (factoryTarget.function.body != null &&
+          !factoryTarget.isRedirectingFactory) {
+        // Use or create the static method that replaces this factory instead.
+        // Note that the static method will not have been created yet in the
+        // case where we visit the factory later. Also note that a cast is not
+        // needed since the static method already has its type erased.
+        var args = super.visitArguments(node.arguments) as Arguments;
+        return StaticInvocation(_findOrCreateFactoryStub(factoryTarget), args,
+            isConst: node.isConst)
+          ..fileOffset = node.fileOffset;
+      } else {
+        // Add a cast so that the result gets typed as `JavaScriptObject`.
+        var newInvocation = super.visitStaticInvocation(node) as Expression;
+        return AsExpression(
+            newInvocation,
+            InterfaceType(_javaScriptObject,
+                node.target.function.returnType.declaredNullability))
+          ..fileOffset = newInvocation.fileOffset;
+      }
+    }
+    return super.visitStaticInvocation(node);
+  }
+
+  @override
+  DartType visitDartType(DartType type) {
+    // Variance is not a factor in our type transformation here, so just choose
+    // `unrelated` as a default.
+    var substitutedType = type.accept1(_typeSubstitutor, Variance.unrelated);
+    return substitutedType != null ? substitutedType : type;
+  }
+}
diff --git a/pkg/analysis_server/analysis_options.yaml b/pkg/analysis_server/analysis_options.yaml
index e737f27..fdda3f2 100644
--- a/pkg/analysis_server/analysis_options.yaml
+++ b/pkg/analysis_server/analysis_options.yaml
@@ -1,10 +1,8 @@
 include: package:pedantic/analysis_options.1.9.0.yaml
 
 analyzer:
-  # This currently finds ~1,200 implicit-casts issues when enabled.
-  # TODO(srawlins): Switch to strict-casts
-  # strong-mode:
-  #   implicit-casts: false
+  language:
+    strict-casts: true
   exclude:
     - test/mock_packages/**
   errors:
diff --git a/pkg/analysis_server/benchmark/benchmarks.dart b/pkg/analysis_server/benchmark/benchmarks.dart
index 78a1b36..7037a85 100644
--- a/pkg/analysis_server/benchmark/benchmarks.dart
+++ b/pkg/analysis_server/benchmark/benchmarks.dart
@@ -10,7 +10,6 @@
 import 'package:analyzer/file_system/physical_file_system.dart';
 import 'package:analyzer_utilities/package_root.dart';
 import 'package:args/command_runner.dart';
-import 'package:intl/intl.dart';
 import 'package:path/path.dart' as path;
 
 import 'perf/benchmarks_impl.dart';
@@ -88,8 +87,6 @@
 }
 
 class BenchMarkResult {
-  static final NumberFormat nf = NumberFormat.decimalPattern();
-
   /// One of 'bytes', 'micros', or 'compound'.
   final String kindName;
 
@@ -104,7 +101,7 @@
   Map toJson() => {kindName: value};
 
   @override
-  String toString() => '$kindName: ${nf.format(value)}';
+  String toString() => '$kindName: $value';
 }
 
 class CompoundBenchMarkResult extends BenchMarkResult {
diff --git a/pkg/analysis_server/benchmark/perf/flutter_completion_benchmark.dart b/pkg/analysis_server/benchmark/perf/flutter_completion_benchmark.dart
index 78497cb..7863130 100644
--- a/pkg/analysis_server/benchmark/perf/flutter_completion_benchmark.dart
+++ b/pkg/analysis_server/benchmark/perf/flutter_completion_benchmark.dart
@@ -33,7 +33,7 @@
         );
 
   @override
-  int get maxIterations => 2;
+  int get maxIterations => 1;
 
   @override
   Future<BenchMarkResult> run({
@@ -243,12 +243,12 @@
     // Perform warm-up.
     // The cold start does not matter.
     // The sustained performance is much more important.
-    const kWarmUpCount = 20;
+    const kWarmUpCount = 5;
     for (var i = 0; i < kWarmUpCount; i++) {
       await perform();
     }
 
-    const kRepeatCount = 10;
+    const kRepeatCount = 5;
     final timer = Stopwatch()..start();
     for (var i = 0; i < kRepeatCount; i++) {
       await perform();
diff --git a/pkg/analysis_server/doc/api.html b/pkg/analysis_server/doc/api.html
index b84e3fd..1bb0ba8 100644
--- a/pkg/analysis_server/doc/api.html
+++ b/pkg/analysis_server/doc/api.html
@@ -109,7 +109,7 @@
 <body>
 <h1>Analysis Server API Specification</h1>
 <h1 style="color:#999999">Version
-  1.32.7
+  1.32.8
 </h1>
 <p>
   This document contains a specification of the API provided by the
@@ -236,6 +236,11 @@
   ignoring the item or treating it with some default/fallback handling.
 </p>
 <h3>Changelog</h3>
+<h4>1.32.8</h4>
+<ul>
+  <li>Added <tt>server.cancelRequest</tt> to allow clients to request cancellation
+  of outstanding requests.</li>
+</ul>
 <h4>1.32.7</h4>
 <ul>
   <li><tt>HoverInformation.elementDescription</tt> may now include linebreaks to
@@ -286,6 +291,7 @@
 <p><a href="#domain_server">Server</a></p><ul><li><a href="#request_server.getVersion">server.getVersion</a></li>
 <li><a href="#request_server.shutdown">server.shutdown</a></li>
 <li><a href="#request_server.setSubscriptions">server.setSubscriptions</a></li>
+<li><a href="#request_server.cancelRequest">server.cancelRequest</a></li>
 </ul>
 
 <p><a href="#domain_analysis">Analysis</a></p><ul><li><a href="#request_analysis.getErrors">analysis.getErrors</a></li>
@@ -421,6 +427,7 @@
   
   
   
+  
 <h3>Requests</h3><dl><dt class="request"><a name="request_server.getVersion">server.getVersion</a></dt><dd><div class="box"><pre>request: {
   "id": String
   "method": "server.getVersion"
@@ -474,6 +481,32 @@
   <h4>parameters:</h4><dl><dt class="field"><b>subscriptions: List&lt;<a href="#type_ServerService">ServerService</a>&gt;</b></dt><dd>
         
         <p>A list of the services being subscribed to.</p>
+      </dd></dl></dd><dt class="request"><a name="request_server.cancelRequest">server.cancelRequest</a></dt><dd><div class="box"><pre>request: {
+  "<b>id</b>": String
+  "method": "server.cancelRequest"
+  "params": {
+    "<b>id</b>": String
+  }
+}</pre><br><pre>response: {
+  "id": String
+  "error": <span style="color:#999999">optional</span> <a href="#type_RequestError">RequestError</a>
+}</pre></div>
+    <p>Requests cancellation of a request sent by the client by id.
+      This is provided on a best-effort basis and there is no
+      guarantee the server will be able to cancel any specific
+      request.
+
+      The server will still always produce a response to the request
+      even in the case of cancellation, but clients should discard
+      any results of any cancelled request because they may be
+      incomplete or inaccurate.
+      
+      This request always completes without error regardless of
+      whether the request is successfully cancelled.</p>
+    
+  <h4>parameters:</h4><dl><dt class="field"><b>id: String</b></dt><dd>
+        
+        <p>The id of the request that should be cancelled.</p>
       </dd></dl></dd></dl><h3>Notifications</h3><dl><dt class="notification"><a name="notification_server.connected">server.connected</a></dt><dd><div class="box"><pre>notification: {
   "event": "server.connected"
   "params": {
@@ -6065,7 +6098,7 @@
   TODO: TBD
 </p>
 <h2 class="domain"><a name="index">Index</a></h2>
-<h3>Domains</h3><h4>server (<a href="#domain_server">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_server.getVersion">getVersion</a></li><li><a href="#request_server.shutdown">shutdown</a></li><li><a href="#request_server.setSubscriptions">setSubscriptions</a></li></ul><h5>Notifications</h5><div class="subindex"><ul><li><a href="#notification_server.connected">connected</a></li><li><a href="#notification_server.error">error</a></li><li><a href="#notification_server.log">log</a></li><li><a href="#notification_server.status">status</a></li></ul></div></div><h4>analysis (<a href="#domain_analysis">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_analysis.getErrors">getErrors</a></li><li><a href="#request_analysis.getHover">getHover</a></li><li><a href="#request_analysis.getLibraryDependencies">getLibraryDependencies</a></li><li><a href="#request_analysis.getNavigation">getNavigation</a></li><li><a href="#request_analysis.getReachableSources">getReachableSources</a></li><li><a href="#request_analysis.reanalyze">reanalyze</a></li><li><a href="#request_analysis.setAnalysisRoots">setAnalysisRoots</a></li><li><a href="#request_analysis.setGeneralSubscriptions">setGeneralSubscriptions</a></li><li><a href="#request_analysis.setPriorityFiles">setPriorityFiles</a></li><li><a href="#request_analysis.setSubscriptions">setSubscriptions</a></li><li><a href="#request_analysis.updateContent">updateContent</a></li><li><a href="#request_analysis.updateOptions">updateOptions</a></li></ul><h5>Notifications</h5><div class="subindex"><ul><li><a href="#notification_analysis.analyzedFiles">analyzedFiles</a></li><li><a href="#notification_analysis.closingLabels">closingLabels</a></li><li><a href="#notification_analysis.errors">errors</a></li><li><a href="#notification_analysis.flushResults">flushResults</a></li><li><a href="#notification_analysis.folding">folding</a></li><li><a href="#notification_analysis.highlights">highlights</a></li><li><a href="#notification_analysis.implemented">implemented</a></li><li><a href="#notification_analysis.invalidate">invalidate</a></li><li><a href="#notification_analysis.navigation">navigation</a></li><li><a href="#notification_analysis.occurrences">occurrences</a></li><li><a href="#notification_analysis.outline">outline</a></li><li><a href="#notification_analysis.overrides">overrides</a></li></ul></div></div><h4>completion (<a href="#domain_completion">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_completion.getSuggestions">getSuggestions</a></li><li><a href="#request_completion.setSubscriptions">setSubscriptions</a></li><li><a href="#request_completion.registerLibraryPaths">registerLibraryPaths</a></li><li><a href="#request_completion.getSuggestionDetails">getSuggestionDetails</a></li></ul><h5>Notifications</h5><div class="subindex"><ul><li><a href="#notification_completion.results">results</a></li><li><a href="#notification_completion.availableSuggestions">availableSuggestions</a></li><li><a href="#notification_completion.existingImports">existingImports</a></li></ul></div></div><h4>search (<a href="#domain_search">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_search.findElementReferences">findElementReferences</a></li><li><a href="#request_search.findMemberDeclarations">findMemberDeclarations</a></li><li><a href="#request_search.findMemberReferences">findMemberReferences</a></li><li><a href="#request_search.findTopLevelDeclarations">findTopLevelDeclarations</a></li><li><a href="#request_search.getTypeHierarchy">getTypeHierarchy</a></li></ul><h5>Notifications</h5><div class="subindex"><ul><li><a href="#notification_search.results">results</a></li></ul></div></div><h4>edit (<a href="#domain_edit">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_edit.format">format</a></li><li><a href="#request_edit.getAssists">getAssists</a></li><li><a href="#request_edit.getAvailableRefactorings">getAvailableRefactorings</a></li><li><a href="#request_edit.getFixes">getFixes</a></li><li><a href="#request_edit.getPostfixCompletion">getPostfixCompletion</a></li><li><a href="#request_edit.getRefactoring">getRefactoring</a></li><li><a href="#request_edit.sortMembers">sortMembers</a></li><li><a href="#request_edit.organizeDirectives">organizeDirectives</a></li></ul></div><h4>execution (<a href="#domain_execution">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_execution.createContext">createContext</a></li><li><a href="#request_execution.deleteContext">deleteContext</a></li><li><a href="#request_execution.getSuggestions">getSuggestions</a></li><li><a href="#request_execution.mapUri">mapUri</a></li><li><a href="#request_execution.setSubscriptions">setSubscriptions</a></li></ul><h5>Notifications</h5><div class="subindex"><ul><li><a href="#notification_execution.launchData">launchData</a></li></ul></div></div><h4>diagnostic (<a href="#domain_diagnostic">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_diagnostic.getDiagnostics">getDiagnostics</a></li><li><a href="#request_diagnostic.getServerPort">getServerPort</a></li></ul></div><h4>flutter (<a href="#domain_flutter">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_flutter.setSubscriptions">setSubscriptions</a></li></ul><h5>Notifications</h5><div class="subindex"><ul><li><a href="#notification_flutter.outline">outline</a></li></ul></div></div><h3>Types (<a href="#types">↑</a>)</h3><div class="subindex"><ul><li><a href="#type_AddContentOverlay">AddContentOverlay</a></li><li><a href="#type_AnalysisError">AnalysisError</a></li><li><a href="#type_AnalysisErrorFixes">AnalysisErrorFixes</a></li><li><a href="#type_AnalysisErrorSeverity">AnalysisErrorSeverity</a></li><li><a href="#type_AnalysisErrorType">AnalysisErrorType</a></li><li><a href="#type_AnalysisOptions">AnalysisOptions</a></li><li><a href="#type_AnalysisService">AnalysisService</a></li><li><a href="#type_AnalysisStatus">AnalysisStatus</a></li><li><a href="#type_AvailableSuggestion">AvailableSuggestion</a></li><li><a href="#type_AvailableSuggestionRelevanceTag">AvailableSuggestionRelevanceTag</a></li><li><a href="#type_AvailableSuggestionSet">AvailableSuggestionSet</a></li><li><a href="#type_BulkFix">BulkFix</a></li><li><a href="#type_BulkFixDetail">BulkFixDetail</a></li><li><a href="#type_ChangeContentOverlay">ChangeContentOverlay</a></li><li><a href="#type_ClosingLabel">ClosingLabel</a></li><li><a href="#type_CompletionId">CompletionId</a></li><li><a href="#type_CompletionService">CompletionService</a></li><li><a href="#type_CompletionSuggestion">CompletionSuggestion</a></li><li><a href="#type_CompletionSuggestionKind">CompletionSuggestionKind</a></li><li><a href="#type_ContextData">ContextData</a></li><li><a href="#type_DiagnosticMessage">DiagnosticMessage</a></li><li><a href="#type_Element">Element</a></li><li><a href="#type_ElementDeclaration">ElementDeclaration</a></li><li><a href="#type_ElementKind">ElementKind</a></li><li><a href="#type_ExecutableFile">ExecutableFile</a></li><li><a href="#type_ExecutableKind">ExecutableKind</a></li><li><a href="#type_ExecutionContextId">ExecutionContextId</a></li><li><a href="#type_ExecutionService">ExecutionService</a></li><li><a href="#type_ExistingImport">ExistingImport</a></li><li><a href="#type_ExistingImports">ExistingImports</a></li><li><a href="#type_FileKind">FileKind</a></li><li><a href="#type_FilePath">FilePath</a></li><li><a href="#type_FlutterOutline">FlutterOutline</a></li><li><a href="#type_FlutterOutlineAttribute">FlutterOutlineAttribute</a></li><li><a href="#type_FlutterOutlineKind">FlutterOutlineKind</a></li><li><a href="#type_FlutterService">FlutterService</a></li><li><a href="#type_FlutterWidgetProperty">FlutterWidgetProperty</a></li><li><a href="#type_FlutterWidgetPropertyEditor">FlutterWidgetPropertyEditor</a></li><li><a href="#type_FlutterWidgetPropertyEditorKind">FlutterWidgetPropertyEditorKind</a></li><li><a href="#type_FlutterWidgetPropertyValue">FlutterWidgetPropertyValue</a></li><li><a href="#type_FlutterWidgetPropertyValueEnumItem">FlutterWidgetPropertyValueEnumItem</a></li><li><a href="#type_FoldingKind">FoldingKind</a></li><li><a href="#type_FoldingRegion">FoldingRegion</a></li><li><a href="#type_GeneralAnalysisService">GeneralAnalysisService</a></li><li><a href="#type_HighlightRegion">HighlightRegion</a></li><li><a href="#type_HighlightRegionType">HighlightRegionType</a></li><li><a href="#type_HoverInformation">HoverInformation</a></li><li><a href="#type_ImplementedClass">ImplementedClass</a></li><li><a href="#type_ImplementedMember">ImplementedMember</a></li><li><a href="#type_ImportedElementSet">ImportedElementSet</a></li><li><a href="#type_ImportedElements">ImportedElements</a></li><li><a href="#type_IncludedSuggestionRelevanceTag">IncludedSuggestionRelevanceTag</a></li><li><a href="#type_IncludedSuggestionSet">IncludedSuggestionSet</a></li><li><a href="#type_KytheEntry">KytheEntry</a></li><li><a href="#type_KytheVName">KytheVName</a></li><li><a href="#type_LibraryPathSet">LibraryPathSet</a></li><li><a href="#type_LinkedEditGroup">LinkedEditGroup</a></li><li><a href="#type_LinkedEditSuggestion">LinkedEditSuggestion</a></li><li><a href="#type_LinkedEditSuggestionKind">LinkedEditSuggestionKind</a></li><li><a href="#type_Location">Location</a></li><li><a href="#type_NavigationRegion">NavigationRegion</a></li><li><a href="#type_NavigationTarget">NavigationTarget</a></li><li><a href="#type_Occurrences">Occurrences</a></li><li><a href="#type_Outline">Outline</a></li><li><a href="#type_OverriddenMember">OverriddenMember</a></li><li><a href="#type_Override">Override</a></li><li><a href="#type_Position">Position</a></li><li><a href="#type_PostfixTemplateDescriptor">PostfixTemplateDescriptor</a></li><li><a href="#type_PubStatus">PubStatus</a></li><li><a href="#type_RefactoringFeedback">RefactoringFeedback</a></li><li><a href="#type_RefactoringKind">RefactoringKind</a></li><li><a href="#type_RefactoringMethodParameter">RefactoringMethodParameter</a></li><li><a href="#type_RefactoringMethodParameterKind">RefactoringMethodParameterKind</a></li><li><a href="#type_RefactoringOptions">RefactoringOptions</a></li><li><a href="#type_RefactoringProblem">RefactoringProblem</a></li><li><a href="#type_RefactoringProblemSeverity">RefactoringProblemSeverity</a></li><li><a href="#type_RemoveContentOverlay">RemoveContentOverlay</a></li><li><a href="#type_RequestError">RequestError</a></li><li><a href="#type_RequestErrorCode">RequestErrorCode</a></li><li><a href="#type_RuntimeCompletionExpression">RuntimeCompletionExpression</a></li><li><a href="#type_RuntimeCompletionExpressionType">RuntimeCompletionExpressionType</a></li><li><a href="#type_RuntimeCompletionExpressionTypeKind">RuntimeCompletionExpressionTypeKind</a></li><li><a href="#type_RuntimeCompletionVariable">RuntimeCompletionVariable</a></li><li><a href="#type_SearchId">SearchId</a></li><li><a href="#type_SearchResult">SearchResult</a></li><li><a href="#type_SearchResultKind">SearchResultKind</a></li><li><a href="#type_ServerService">ServerService</a></li><li><a href="#type_SourceChange">SourceChange</a></li><li><a href="#type_SourceEdit">SourceEdit</a></li><li><a href="#type_SourceFileEdit">SourceFileEdit</a></li><li><a href="#type_TypeHierarchyItem">TypeHierarchyItem</a></li></ul></div><h3>Refactorings (<a href="#refactorings">↑</a>)</h3><div class="subindex"><ul><li><a href="#refactoring_CONVERT_GETTER_TO_METHOD">CONVERT_GETTER_TO_METHOD</a></li><li><a href="#refactoring_CONVERT_METHOD_TO_GETTER">CONVERT_METHOD_TO_GETTER</a></li><li><a href="#refactoring_EXTRACT_LOCAL_VARIABLE">EXTRACT_LOCAL_VARIABLE</a></li><li><a href="#refactoring_EXTRACT_METHOD">EXTRACT_METHOD</a></li><li><a href="#refactoring_EXTRACT_WIDGET">EXTRACT_WIDGET</a></li><li><a href="#refactoring_INLINE_LOCAL_VARIABLE">INLINE_LOCAL_VARIABLE</a></li><li><a href="#refactoring_INLINE_METHOD">INLINE_METHOD</a></li><li><a href="#refactoring_MOVE_FILE">MOVE_FILE</a></li><li><a href="#refactoring_RENAME">RENAME</a></li></ul></div>
+<h3>Domains</h3><h4>server (<a href="#domain_server">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_server.getVersion">getVersion</a></li><li><a href="#request_server.shutdown">shutdown</a></li><li><a href="#request_server.setSubscriptions">setSubscriptions</a></li><li><a href="#request_server.cancelRequest">cancelRequest</a></li></ul><h5>Notifications</h5><div class="subindex"><ul><li><a href="#notification_server.connected">connected</a></li><li><a href="#notification_server.error">error</a></li><li><a href="#notification_server.log">log</a></li><li><a href="#notification_server.status">status</a></li></ul></div></div><h4>analysis (<a href="#domain_analysis">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_analysis.getErrors">getErrors</a></li><li><a href="#request_analysis.getHover">getHover</a></li><li><a href="#request_analysis.getLibraryDependencies">getLibraryDependencies</a></li><li><a href="#request_analysis.getNavigation">getNavigation</a></li><li><a href="#request_analysis.getReachableSources">getReachableSources</a></li><li><a href="#request_analysis.reanalyze">reanalyze</a></li><li><a href="#request_analysis.setAnalysisRoots">setAnalysisRoots</a></li><li><a href="#request_analysis.setGeneralSubscriptions">setGeneralSubscriptions</a></li><li><a href="#request_analysis.setPriorityFiles">setPriorityFiles</a></li><li><a href="#request_analysis.setSubscriptions">setSubscriptions</a></li><li><a href="#request_analysis.updateContent">updateContent</a></li><li><a href="#request_analysis.updateOptions">updateOptions</a></li></ul><h5>Notifications</h5><div class="subindex"><ul><li><a href="#notification_analysis.analyzedFiles">analyzedFiles</a></li><li><a href="#notification_analysis.closingLabels">closingLabels</a></li><li><a href="#notification_analysis.errors">errors</a></li><li><a href="#notification_analysis.flushResults">flushResults</a></li><li><a href="#notification_analysis.folding">folding</a></li><li><a href="#notification_analysis.highlights">highlights</a></li><li><a href="#notification_analysis.implemented">implemented</a></li><li><a href="#notification_analysis.invalidate">invalidate</a></li><li><a href="#notification_analysis.navigation">navigation</a></li><li><a href="#notification_analysis.occurrences">occurrences</a></li><li><a href="#notification_analysis.outline">outline</a></li><li><a href="#notification_analysis.overrides">overrides</a></li></ul></div></div><h4>completion (<a href="#domain_completion">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_completion.getSuggestions">getSuggestions</a></li><li><a href="#request_completion.setSubscriptions">setSubscriptions</a></li><li><a href="#request_completion.registerLibraryPaths">registerLibraryPaths</a></li><li><a href="#request_completion.getSuggestionDetails">getSuggestionDetails</a></li></ul><h5>Notifications</h5><div class="subindex"><ul><li><a href="#notification_completion.results">results</a></li><li><a href="#notification_completion.availableSuggestions">availableSuggestions</a></li><li><a href="#notification_completion.existingImports">existingImports</a></li></ul></div></div><h4>search (<a href="#domain_search">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_search.findElementReferences">findElementReferences</a></li><li><a href="#request_search.findMemberDeclarations">findMemberDeclarations</a></li><li><a href="#request_search.findMemberReferences">findMemberReferences</a></li><li><a href="#request_search.findTopLevelDeclarations">findTopLevelDeclarations</a></li><li><a href="#request_search.getTypeHierarchy">getTypeHierarchy</a></li></ul><h5>Notifications</h5><div class="subindex"><ul><li><a href="#notification_search.results">results</a></li></ul></div></div><h4>edit (<a href="#domain_edit">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_edit.format">format</a></li><li><a href="#request_edit.getAssists">getAssists</a></li><li><a href="#request_edit.getAvailableRefactorings">getAvailableRefactorings</a></li><li><a href="#request_edit.getFixes">getFixes</a></li><li><a href="#request_edit.getPostfixCompletion">getPostfixCompletion</a></li><li><a href="#request_edit.getRefactoring">getRefactoring</a></li><li><a href="#request_edit.sortMembers">sortMembers</a></li><li><a href="#request_edit.organizeDirectives">organizeDirectives</a></li></ul></div><h4>execution (<a href="#domain_execution">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_execution.createContext">createContext</a></li><li><a href="#request_execution.deleteContext">deleteContext</a></li><li><a href="#request_execution.getSuggestions">getSuggestions</a></li><li><a href="#request_execution.mapUri">mapUri</a></li><li><a href="#request_execution.setSubscriptions">setSubscriptions</a></li></ul><h5>Notifications</h5><div class="subindex"><ul><li><a href="#notification_execution.launchData">launchData</a></li></ul></div></div><h4>diagnostic (<a href="#domain_diagnostic">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_diagnostic.getDiagnostics">getDiagnostics</a></li><li><a href="#request_diagnostic.getServerPort">getServerPort</a></li></ul></div><h4>flutter (<a href="#domain_flutter">↑</a>)</h4><div class="subindex"><h5>Requests</h5><ul><li><a href="#request_flutter.setSubscriptions">setSubscriptions</a></li></ul><h5>Notifications</h5><div class="subindex"><ul><li><a href="#notification_flutter.outline">outline</a></li></ul></div></div><h3>Types (<a href="#types">↑</a>)</h3><div class="subindex"><ul><li><a href="#type_AddContentOverlay">AddContentOverlay</a></li><li><a href="#type_AnalysisError">AnalysisError</a></li><li><a href="#type_AnalysisErrorFixes">AnalysisErrorFixes</a></li><li><a href="#type_AnalysisErrorSeverity">AnalysisErrorSeverity</a></li><li><a href="#type_AnalysisErrorType">AnalysisErrorType</a></li><li><a href="#type_AnalysisOptions">AnalysisOptions</a></li><li><a href="#type_AnalysisService">AnalysisService</a></li><li><a href="#type_AnalysisStatus">AnalysisStatus</a></li><li><a href="#type_AvailableSuggestion">AvailableSuggestion</a></li><li><a href="#type_AvailableSuggestionRelevanceTag">AvailableSuggestionRelevanceTag</a></li><li><a href="#type_AvailableSuggestionSet">AvailableSuggestionSet</a></li><li><a href="#type_BulkFix">BulkFix</a></li><li><a href="#type_BulkFixDetail">BulkFixDetail</a></li><li><a href="#type_ChangeContentOverlay">ChangeContentOverlay</a></li><li><a href="#type_ClosingLabel">ClosingLabel</a></li><li><a href="#type_CompletionId">CompletionId</a></li><li><a href="#type_CompletionService">CompletionService</a></li><li><a href="#type_CompletionSuggestion">CompletionSuggestion</a></li><li><a href="#type_CompletionSuggestionKind">CompletionSuggestionKind</a></li><li><a href="#type_ContextData">ContextData</a></li><li><a href="#type_DiagnosticMessage">DiagnosticMessage</a></li><li><a href="#type_Element">Element</a></li><li><a href="#type_ElementDeclaration">ElementDeclaration</a></li><li><a href="#type_ElementKind">ElementKind</a></li><li><a href="#type_ExecutableFile">ExecutableFile</a></li><li><a href="#type_ExecutableKind">ExecutableKind</a></li><li><a href="#type_ExecutionContextId">ExecutionContextId</a></li><li><a href="#type_ExecutionService">ExecutionService</a></li><li><a href="#type_ExistingImport">ExistingImport</a></li><li><a href="#type_ExistingImports">ExistingImports</a></li><li><a href="#type_FileKind">FileKind</a></li><li><a href="#type_FilePath">FilePath</a></li><li><a href="#type_FlutterOutline">FlutterOutline</a></li><li><a href="#type_FlutterOutlineAttribute">FlutterOutlineAttribute</a></li><li><a href="#type_FlutterOutlineKind">FlutterOutlineKind</a></li><li><a href="#type_FlutterService">FlutterService</a></li><li><a href="#type_FlutterWidgetProperty">FlutterWidgetProperty</a></li><li><a href="#type_FlutterWidgetPropertyEditor">FlutterWidgetPropertyEditor</a></li><li><a href="#type_FlutterWidgetPropertyEditorKind">FlutterWidgetPropertyEditorKind</a></li><li><a href="#type_FlutterWidgetPropertyValue">FlutterWidgetPropertyValue</a></li><li><a href="#type_FlutterWidgetPropertyValueEnumItem">FlutterWidgetPropertyValueEnumItem</a></li><li><a href="#type_FoldingKind">FoldingKind</a></li><li><a href="#type_FoldingRegion">FoldingRegion</a></li><li><a href="#type_GeneralAnalysisService">GeneralAnalysisService</a></li><li><a href="#type_HighlightRegion">HighlightRegion</a></li><li><a href="#type_HighlightRegionType">HighlightRegionType</a></li><li><a href="#type_HoverInformation">HoverInformation</a></li><li><a href="#type_ImplementedClass">ImplementedClass</a></li><li><a href="#type_ImplementedMember">ImplementedMember</a></li><li><a href="#type_ImportedElementSet">ImportedElementSet</a></li><li><a href="#type_ImportedElements">ImportedElements</a></li><li><a href="#type_IncludedSuggestionRelevanceTag">IncludedSuggestionRelevanceTag</a></li><li><a href="#type_IncludedSuggestionSet">IncludedSuggestionSet</a></li><li><a href="#type_KytheEntry">KytheEntry</a></li><li><a href="#type_KytheVName">KytheVName</a></li><li><a href="#type_LibraryPathSet">LibraryPathSet</a></li><li><a href="#type_LinkedEditGroup">LinkedEditGroup</a></li><li><a href="#type_LinkedEditSuggestion">LinkedEditSuggestion</a></li><li><a href="#type_LinkedEditSuggestionKind">LinkedEditSuggestionKind</a></li><li><a href="#type_Location">Location</a></li><li><a href="#type_NavigationRegion">NavigationRegion</a></li><li><a href="#type_NavigationTarget">NavigationTarget</a></li><li><a href="#type_Occurrences">Occurrences</a></li><li><a href="#type_Outline">Outline</a></li><li><a href="#type_OverriddenMember">OverriddenMember</a></li><li><a href="#type_Override">Override</a></li><li><a href="#type_Position">Position</a></li><li><a href="#type_PostfixTemplateDescriptor">PostfixTemplateDescriptor</a></li><li><a href="#type_PubStatus">PubStatus</a></li><li><a href="#type_RefactoringFeedback">RefactoringFeedback</a></li><li><a href="#type_RefactoringKind">RefactoringKind</a></li><li><a href="#type_RefactoringMethodParameter">RefactoringMethodParameter</a></li><li><a href="#type_RefactoringMethodParameterKind">RefactoringMethodParameterKind</a></li><li><a href="#type_RefactoringOptions">RefactoringOptions</a></li><li><a href="#type_RefactoringProblem">RefactoringProblem</a></li><li><a href="#type_RefactoringProblemSeverity">RefactoringProblemSeverity</a></li><li><a href="#type_RemoveContentOverlay">RemoveContentOverlay</a></li><li><a href="#type_RequestError">RequestError</a></li><li><a href="#type_RequestErrorCode">RequestErrorCode</a></li><li><a href="#type_RuntimeCompletionExpression">RuntimeCompletionExpression</a></li><li><a href="#type_RuntimeCompletionExpressionType">RuntimeCompletionExpressionType</a></li><li><a href="#type_RuntimeCompletionExpressionTypeKind">RuntimeCompletionExpressionTypeKind</a></li><li><a href="#type_RuntimeCompletionVariable">RuntimeCompletionVariable</a></li><li><a href="#type_SearchId">SearchId</a></li><li><a href="#type_SearchResult">SearchResult</a></li><li><a href="#type_SearchResultKind">SearchResultKind</a></li><li><a href="#type_ServerService">ServerService</a></li><li><a href="#type_SourceChange">SourceChange</a></li><li><a href="#type_SourceEdit">SourceEdit</a></li><li><a href="#type_SourceFileEdit">SourceFileEdit</a></li><li><a href="#type_TypeHierarchyItem">TypeHierarchyItem</a></li></ul></div><h3>Refactorings (<a href="#refactorings">↑</a>)</h3><div class="subindex"><ul><li><a href="#refactoring_CONVERT_GETTER_TO_METHOD">CONVERT_GETTER_TO_METHOD</a></li><li><a href="#refactoring_CONVERT_METHOD_TO_GETTER">CONVERT_METHOD_TO_GETTER</a></li><li><a href="#refactoring_EXTRACT_LOCAL_VARIABLE">EXTRACT_LOCAL_VARIABLE</a></li><li><a href="#refactoring_EXTRACT_METHOD">EXTRACT_METHOD</a></li><li><a href="#refactoring_EXTRACT_WIDGET">EXTRACT_WIDGET</a></li><li><a href="#refactoring_INLINE_LOCAL_VARIABLE">INLINE_LOCAL_VARIABLE</a></li><li><a href="#refactoring_INLINE_METHOD">INLINE_METHOD</a></li><li><a href="#refactoring_MOVE_FILE">MOVE_FILE</a></li><li><a href="#refactoring_RENAME">RENAME</a></li></ul></div>
 
 
 </body></html>
\ No newline at end of file
diff --git a/pkg/analysis_server/lib/lsp_protocol/protocol_custom_generated.dart b/pkg/analysis_server/lib/lsp_protocol/protocol_custom_generated.dart
index 03ef62f..5c222c3 100644
--- a/pkg/analysis_server/lib/lsp_protocol/protocol_custom_generated.dart
+++ b/pkg/analysis_server/lib/lsp_protocol/protocol_custom_generated.dart
@@ -846,7 +846,7 @@
       try {
         final attributes = obj['attributes'];
         if (attributes != null &&
-            !((attributes is List &&
+            !((attributes is List<Object?> &&
                 (attributes.every((item) =>
                     FlutterOutlineAttribute.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<FlutterOutlineAttribute>');
@@ -905,7 +905,7 @@
       try {
         final children = obj['children'];
         if (children != null &&
-            !((children is List &&
+            !((children is List<Object?> &&
                 (children.every(
                     (item) => FlutterOutline.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<FlutterOutline>');
@@ -1168,7 +1168,7 @@
       try {
         final children = obj['children'];
         if (children != null &&
-            !((children is List &&
+            !((children is List<Object?> &&
                 (children
                     .every((item) => Outline.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<Outline>');
@@ -1376,7 +1376,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((labels is List &&
+        if (!((labels is List<Object?> &&
             (labels.every((item) => ClosingLabel.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<ClosingLabel>');
           return false;
diff --git a/pkg/analysis_server/lib/lsp_protocol/protocol_generated.dart b/pkg/analysis_server/lib/lsp_protocol/protocol_generated.dart
index e792375..e8de391 100644
--- a/pkg/analysis_server/lib/lsp_protocol/protocol_generated.dart
+++ b/pkg/analysis_server/lib/lsp_protocol/protocol_generated.dart
@@ -452,7 +452,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((fromRanges is List &&
+        if (!((fromRanges is List<Object?> &&
             (fromRanges.every((item) => Range.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<Range>');
           return false;
@@ -741,7 +741,7 @@
       try {
         final tags = obj['tags'];
         if (tags != null &&
-            !((tags is List &&
+            !((tags is List<Object?> &&
                 (tags.every((item) => SymbolTag.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<SymbolTag>');
           return false;
@@ -963,7 +963,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((fromRanges is List &&
+        if (!((fromRanges is List<Object?> &&
             (fromRanges.every((item) => Range.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<Range>');
           return false;
@@ -1298,7 +1298,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -2585,7 +2585,7 @@
       try {
         final diagnostics = obj['diagnostics'];
         if (diagnostics != null &&
-            !((diagnostics is List &&
+            !((diagnostics is List<Object?> &&
                 (diagnostics
                     .every((item) => Diagnostic.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<Diagnostic>');
@@ -2926,7 +2926,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((valueSet is List &&
+        if (!((valueSet is List<Object?> &&
             (valueSet
                 .every((item) => CodeActionKind.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<CodeActionKind>');
@@ -3071,7 +3071,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((properties is List &&
+        if (!((properties is List<Object?> &&
             (properties.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -3160,7 +3160,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((diagnostics is List &&
+        if (!((diagnostics is List<Object?> &&
             (diagnostics
                 .every((item) => Diagnostic.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<Diagnostic>');
@@ -3173,7 +3173,7 @@
       try {
         final only = obj['only'];
         if (only != null &&
-            !((only is List &&
+            !((only is List<Object?> &&
                 (only.every(
                     (item) => CodeActionKind.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<CodeActionKind>');
@@ -3280,7 +3280,7 @@
 
   final String _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is String;
   }
 
@@ -3402,7 +3402,7 @@
       try {
         final codeActionKinds = obj['codeActionKinds'];
         if (codeActionKinds != null &&
-            !((codeActionKinds is List &&
+            !((codeActionKinds is List<Object?> &&
                 (codeActionKinds.every(
                     (item) => CodeActionKind.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<CodeActionKind>');
@@ -3712,7 +3712,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -3725,7 +3725,7 @@
       try {
         final codeActionKinds = obj['codeActionKinds'];
         if (codeActionKinds != null &&
-            !((codeActionKinds is List &&
+            !((codeActionKinds is List<Object?> &&
                 (codeActionKinds.every(
                     (item) => CodeActionKind.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<CodeActionKind>');
@@ -4262,7 +4262,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -4698,7 +4698,7 @@
       try {
         final additionalTextEdits = obj['additionalTextEdits'];
         if (additionalTextEdits != null &&
-            !((additionalTextEdits is List &&
+            !((additionalTextEdits is List<Object?> &&
                 (additionalTextEdits
                     .every((item) => TextEdit.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<TextEdit>');
@@ -4990,7 +4990,8 @@
       try {
         final arguments = obj['arguments'];
         if (arguments != null &&
-            !((arguments is List && (arguments.every((item) => true))))) {
+            !((arguments is List<Object?> &&
+                (arguments.every((item) => true))))) {
           reporter.reportError('must be of type List<Object?>');
           return false;
         }
@@ -5323,7 +5324,7 @@
       try {
         final documentationFormat = obj['documentationFormat'];
         if (documentationFormat != null &&
-            !((documentationFormat is List &&
+            !((documentationFormat is List<Object?> &&
                 (documentationFormat
                     .every((item) => MarkupKind.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<MarkupKind>');
@@ -5482,7 +5483,7 @@
       try {
         final valueSet = obj['valueSet'];
         if (valueSet != null &&
-            !((valueSet is List &&
+            !((valueSet is List<Object?> &&
                 (valueSet.every(
                     (item) => CompletionItemKind.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<CompletionItemKind>');
@@ -5554,7 +5555,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((valueSet is List &&
+        if (!((valueSet is List<Object?> &&
             (valueSet
                 .every((item) => InsertTextMode.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<InsertTextMode>');
@@ -5627,7 +5628,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((properties is List &&
+        if (!((properties is List<Object?> &&
             (properties.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -5698,7 +5699,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((valueSet is List &&
+        if (!((valueSet is List<Object?> &&
             (valueSet.every(
                 (item) => CompletionItemTag.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<CompletionItemTag>');
@@ -6124,7 +6125,7 @@
       try {
         final tags = obj['tags'];
         if (tags != null &&
-            !((tags is List &&
+            !((tags is List<Object?> &&
                 (tags.every(
                     (item) => CompletionItemTag.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<CompletionItemTag>');
@@ -6245,7 +6246,7 @@
       try {
         final additionalTextEdits = obj['additionalTextEdits'];
         if (additionalTextEdits != null &&
-            !((additionalTextEdits is List &&
+            !((additionalTextEdits is List<Object?> &&
                 (additionalTextEdits
                     .every((item) => TextEdit.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<TextEdit>');
@@ -6258,7 +6259,7 @@
       try {
         final commitCharacters = obj['commitCharacters'];
         if (commitCharacters != null &&
-            !((commitCharacters is List &&
+            !((commitCharacters is List<Object?> &&
                 (commitCharacters.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -6353,7 +6354,7 @@
 
   final int _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is int;
   }
 
@@ -6403,7 +6404,7 @@
 
   final int _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is int;
   }
 
@@ -6483,7 +6484,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((items is List &&
+        if (!((items is List<Object?> &&
             (items
                 .every((item) => CompletionItem.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<CompletionItem>');
@@ -6600,7 +6601,7 @@
       try {
         final triggerCharacters = obj['triggerCharacters'];
         if (triggerCharacters != null &&
-            !((triggerCharacters is List &&
+            !((triggerCharacters is List<Object?> &&
                 (triggerCharacters.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -6612,7 +6613,7 @@
       try {
         final allCommitCharacters = obj['allCommitCharacters'];
         if (allCommitCharacters != null &&
-            !((allCommitCharacters is List &&
+            !((allCommitCharacters is List<Object?> &&
                 (allCommitCharacters.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -6946,7 +6947,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -6959,7 +6960,7 @@
       try {
         final triggerCharacters = obj['triggerCharacters'];
         if (triggerCharacters != null &&
-            !((triggerCharacters is List &&
+            !((triggerCharacters is List<Object?> &&
                 (triggerCharacters.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -6971,7 +6972,7 @@
       try {
         final allCommitCharacters = obj['allCommitCharacters'];
         if (allCommitCharacters != null &&
-            !((allCommitCharacters is List &&
+            !((allCommitCharacters is List<Object?> &&
                 (allCommitCharacters.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -7042,7 +7043,7 @@
 
   final num _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     switch (obj) {
       case 1:
       case 2:
@@ -7183,7 +7184,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((items is List &&
+        if (!((items is List<Object?> &&
             (items.every(
                 (item) => ConfigurationItem.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<ConfigurationItem>');
@@ -7473,7 +7474,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((files is List &&
+        if (!((files is List<Object?> &&
             (files.every((item) => FileCreate.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<FileCreate>');
           return false;
@@ -7869,7 +7870,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -8252,7 +8253,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -8554,7 +8555,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((files is List &&
+        if (!((files is List<Object?> &&
             (files.every((item) => FileDelete.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<FileDelete>');
           return false;
@@ -8788,7 +8789,7 @@
       try {
         final tags = obj['tags'];
         if (tags != null &&
-            !((tags is List &&
+            !((tags is List<Object?> &&
                 (tags.every(
                     (item) => DiagnosticTag.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DiagnosticTag>');
@@ -8801,7 +8802,7 @@
       try {
         final relatedInformation = obj['relatedInformation'];
         if (relatedInformation != null &&
-            !((relatedInformation is List &&
+            !((relatedInformation is List<Object?> &&
                 (relatedInformation.every((item) =>
                     DiagnosticRelatedInformation.canParse(item, reporter)))))) {
           reporter.reportError(
@@ -8954,7 +8955,7 @@
 
   final num _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is num;
   }
 
@@ -8989,7 +8990,7 @@
 
   final num _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is num;
   }
 
@@ -9211,7 +9212,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((contentChanges is List &&
+        if (!((contentChanges is List<Object?> &&
             (contentChanges.every((item) =>
                 (TextDocumentContentChangeEvent1.canParse(item, reporter) ||
                     TextDocumentContentChangeEvent2.canParse(
@@ -9356,7 +9357,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((changes is List &&
+        if (!((changes is List<Object?> &&
             (changes.every((item) => FileEvent.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<FileEvent>');
           return false;
@@ -9427,7 +9428,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((watchers is List &&
+        if (!((watchers is List<Object?> &&
             (watchers.every(
                 (item) => FileSystemWatcher.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<FileSystemWatcher>');
@@ -10040,7 +10041,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -10493,7 +10494,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -10693,7 +10694,7 @@
 
   final int _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is int;
   }
 
@@ -10982,7 +10983,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -11492,7 +11493,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -11672,7 +11673,7 @@
       try {
         final moreTriggerCharacter = obj['moreTriggerCharacter'];
         if (moreTriggerCharacter != null &&
-            !((moreTriggerCharacter is List &&
+            !((moreTriggerCharacter is List<Object?> &&
                 (moreTriggerCharacter.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -11919,7 +11920,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -11950,7 +11951,7 @@
       try {
         final moreTriggerCharacter = obj['moreTriggerCharacter'];
         if (moreTriggerCharacter != null &&
-            !((moreTriggerCharacter is List &&
+            !((moreTriggerCharacter is List<Object?> &&
                 (moreTriggerCharacter.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -12310,7 +12311,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -12512,7 +12513,7 @@
       try {
         final tags = obj['tags'];
         if (tags != null &&
-            !((tags is List &&
+            !((tags is List<Object?> &&
                 (tags.every((item) => SymbolTag.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<SymbolTag>');
           return false;
@@ -12570,7 +12571,7 @@
       try {
         final children = obj['children'];
         if (children != null &&
-            !((children is List &&
+            !((children is List<Object?> &&
                 (children.every(
                     (item) => DocumentSymbol.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentSymbol>');
@@ -12818,7 +12819,7 @@
       try {
         final valueSet = obj['valueSet'];
         if (valueSet != null &&
-            !((valueSet is List &&
+            !((valueSet is List<Object?> &&
                 (valueSet
                     .every((item) => SymbolKind.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<SymbolKind>');
@@ -12890,7 +12891,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((valueSet is List &&
+        if (!((valueSet is List<Object?> &&
             (valueSet.every((item) => SymbolTag.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<SymbolTag>');
           return false;
@@ -13189,7 +13190,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -13252,7 +13253,7 @@
 
   final int _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is int;
   }
 
@@ -13402,7 +13403,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((commands is List &&
+        if (!((commands is List<Object?> &&
             (commands.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -13515,7 +13516,8 @@
       try {
         final arguments = obj['arguments'];
         if (arguments != null &&
-            !((arguments is List && (arguments.every((item) => true))))) {
+            !((arguments is List<Object?> &&
+                (arguments.every((item) => true))))) {
           reporter.reportError('must be of type List<Object?>');
           return false;
         }
@@ -13606,7 +13608,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((commands is List &&
+        if (!((commands is List<Object?> &&
             (commands.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -13656,7 +13658,7 @@
 
   final String _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     switch (obj) {
       case 'abort':
       case 'transactional':
@@ -13704,7 +13706,7 @@
 
   final int _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is int;
   }
 
@@ -14160,7 +14162,7 @@
 
   final String _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is String;
   }
 
@@ -14281,7 +14283,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((filters is List &&
+        if (!((filters is List<Object?> &&
             (filters.every(
                 (item) => FileOperationFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<FileOperationFilter>');
@@ -14781,7 +14783,7 @@
 
   final String _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is String;
   }
 
@@ -15048,7 +15050,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -15408,7 +15410,7 @@
       try {
         final contentFormat = obj['contentFormat'];
         if (contentFormat != null &&
-            !((contentFormat is List &&
+            !((contentFormat is List<Object?> &&
                 (contentFormat
                     .every((item) => MarkupKind.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<MarkupKind>');
@@ -15663,7 +15665,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -16066,7 +16068,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -16356,7 +16358,7 @@
       try {
         final workspaceFolders = obj['workspaceFolders'];
         if (workspaceFolders != null &&
-            !((workspaceFolders is List &&
+            !((workspaceFolders is List<Object?> &&
                 (workspaceFolders.every(
                     (item) => WorkspaceFolder.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<WorkspaceFolder>');
@@ -16831,7 +16833,7 @@
 
   final int _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     switch (obj) {
       case 1:
       case 2:
@@ -16870,7 +16872,7 @@
 
   final num _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is num;
   }
 
@@ -17203,7 +17205,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -17308,7 +17310,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((ranges is List &&
+        if (!((ranges is List<Object?> &&
             (ranges.every((item) => Range.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<Range>');
           return false;
@@ -17955,7 +17957,7 @@
 
   final String _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     switch (obj) {
       case 'plaintext':
       case 'markdown':
@@ -18118,7 +18120,7 @@
 
   final int _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is int;
   }
 
@@ -18152,7 +18154,7 @@
 
   final String _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is String;
   }
 
@@ -18624,7 +18626,7 @@
 
   final String _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is String;
   }
 
@@ -18904,7 +18906,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -19567,7 +19569,7 @@
 
   final num _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is num;
   }
 
@@ -19859,7 +19861,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((valueSet is List &&
+        if (!((valueSet is List<Object?> &&
             (valueSet
                 .every((item) => DiagnosticTag.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DiagnosticTag>');
@@ -19975,7 +19977,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((diagnostics is List &&
+        if (!((diagnostics is List<Object?> &&
             (diagnostics
                 .every((item) => Diagnostic.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<Diagnostic>');
@@ -20584,7 +20586,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -20765,7 +20767,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((registrations is List &&
+        if (!((registrations is List<Object?> &&
             (registrations
                 .every((item) => Registration.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<Registration>');
@@ -21317,7 +21319,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((files is List &&
+        if (!((files is List<Object?> &&
             (files.every((item) => FileRename.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<FileRename>');
           return false;
@@ -21630,7 +21632,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -21822,7 +21824,7 @@
 
   final String _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     switch (obj) {
       case 'create':
       case 'rename':
@@ -22440,7 +22442,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((positions is List &&
+        if (!((positions is List<Object?> &&
             (positions.every((item) => Position.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<Position>');
           return false;
@@ -22567,7 +22569,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -22620,7 +22622,7 @@
 
   final String _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is String;
   }
 
@@ -22653,7 +22655,7 @@
 
   final String _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is String;
   }
 
@@ -22749,7 +22751,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((data is List && (data.every((item) => item is int))))) {
+        if (!((data is List<Object?> && (data.every((item) => item is int))))) {
           reporter.reportError('must be of type List<int>');
           return false;
         }
@@ -22917,7 +22919,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((tokenTypes is List &&
+        if (!((tokenTypes is List<Object?> &&
             (tokenTypes.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -22936,7 +22938,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((tokenModifiers is List &&
+        if (!((tokenModifiers is List<Object?> &&
             (tokenModifiers.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -22955,7 +22957,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((formats is List &&
+        if (!((formats is List<Object?> &&
             (formats.every((item) => TokenFormat.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<TokenFormat>');
           return false;
@@ -23284,7 +23286,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((edits is List &&
+        if (!((edits is List<Object?> &&
             (edits.every(
                 (item) => SemanticTokensEdit.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<SemanticTokensEdit>');
@@ -23509,7 +23511,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((edits is List &&
+        if (!((edits is List<Object?> &&
             (edits.every(
                 (item) => SemanticTokensEdit.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<SemanticTokensEdit>');
@@ -23622,7 +23624,7 @@
       try {
         final data = obj['data'];
         if (data != null &&
-            !((data is List && (data.every((item) => item is int))))) {
+            !((data is List<Object?> && (data.every((item) => item is int))))) {
           reporter.reportError('must be of type List<int>');
           return false;
         }
@@ -23700,7 +23702,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((tokenTypes is List &&
+        if (!((tokenTypes is List<Object?> &&
             (tokenTypes.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -23719,7 +23721,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((tokenModifiers is List &&
+        if (!((tokenModifiers is List<Object?> &&
             (tokenModifiers.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -24162,7 +24164,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((data is List && (data.every((item) => item is int))))) {
+        if (!((data is List<Object?> && (data.every((item) => item is int))))) {
           reporter.reportError('must be of type List<int>');
           return false;
         }
@@ -24452,7 +24454,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -26627,7 +26629,7 @@
       try {
         final actions = obj['actions'];
         if (actions != null &&
-            !((actions is List &&
+            !((actions is List<Object?> &&
                 (actions.every(
                     (item) => MessageActionItem.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<MessageActionItem>');
@@ -26735,7 +26737,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((signatures is List &&
+        if (!((signatures is List<Object?> &&
             (signatures.every(
                 (item) => SignatureInformation.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<SignatureInformation>');
@@ -27036,7 +27038,7 @@
       try {
         final documentationFormat = obj['documentationFormat'];
         if (documentationFormat != null &&
-            !((documentationFormat is List &&
+            !((documentationFormat is List<Object?> &&
                 (documentationFormat
                     .every((item) => MarkupKind.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<MarkupKind>');
@@ -27312,7 +27314,7 @@
       try {
         final triggerCharacters = obj['triggerCharacters'];
         if (triggerCharacters != null &&
-            !((triggerCharacters is List &&
+            !((triggerCharacters is List<Object?> &&
                 (triggerCharacters.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -27324,7 +27326,7 @@
       try {
         final retriggerCharacters = obj['retriggerCharacters'];
         if (retriggerCharacters != null &&
-            !((retriggerCharacters is List &&
+            !((retriggerCharacters is List<Object?> &&
                 (retriggerCharacters.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -27598,7 +27600,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -27611,7 +27613,7 @@
       try {
         final triggerCharacters = obj['triggerCharacters'];
         if (triggerCharacters != null &&
-            !((triggerCharacters is List &&
+            !((triggerCharacters is List<Object?> &&
                 (triggerCharacters.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -27623,7 +27625,7 @@
       try {
         final retriggerCharacters = obj['retriggerCharacters'];
         if (retriggerCharacters != null &&
-            !((retriggerCharacters is List &&
+            !((retriggerCharacters is List<Object?> &&
                 (retriggerCharacters.every((item) => item is String))))) {
           reporter.reportError('must be of type List<String>');
           return false;
@@ -27683,7 +27685,7 @@
 
   final num _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is num;
   }
 
@@ -27815,7 +27817,7 @@
       try {
         final parameters = obj['parameters'];
         if (parameters != null &&
-            !((parameters is List &&
+            !((parameters is List<Object?> &&
                 (parameters.every((item) =>
                     ParameterInformation.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<ParameterInformation>');
@@ -28077,7 +28079,7 @@
       try {
         final tags = obj['tags'];
         if (tags != null &&
-            !((tags is List &&
+            !((tags is List<Object?> &&
                 (tags.every((item) => SymbolTag.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<SymbolTag>');
           return false;
@@ -28159,7 +28161,7 @@
 
   final int _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is int;
   }
 
@@ -28209,7 +28211,7 @@
 
   final num _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is num;
   }
 
@@ -28292,7 +28294,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -29338,7 +29340,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((edits is List &&
+        if (!((edits is List<Object?> &&
             (edits.every((item) => (SnippetTextEdit.canParse(item, reporter) ||
                 AnnotatedTextEdit.canParse(item, reporter) ||
                 TextEdit.canParse(item, reporter))))))) {
@@ -29850,7 +29852,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -29891,7 +29893,7 @@
 
   final int _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is int;
   }
 
@@ -29973,7 +29975,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -30146,7 +30148,7 @@
 
   final int _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is int;
   }
 
@@ -30433,7 +30435,7 @@
 
   final String _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is String;
   }
 
@@ -30807,7 +30809,7 @@
         }
         final documentSelector = obj['documentSelector'];
         if (documentSelector != null &&
-            !((documentSelector is List &&
+            !((documentSelector is List<Object?> &&
                 (documentSelector.every(
                     (item) => DocumentFilter.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<DocumentFilter>');
@@ -30871,7 +30873,7 @@
 
   final String _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is String;
   }
 
@@ -31027,7 +31029,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((unregisterations is List &&
+        if (!((unregisterations is List<Object?> &&
             (unregisterations
                 .every((item) => Unregistration.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<Unregistration>');
@@ -31159,7 +31161,7 @@
 
   final int _value;
 
-  static bool canParse(Object obj, LspJsonReporter reporter) {
+  static bool canParse(Object? obj, LspJsonReporter reporter) {
     return obj is int;
   }
 
@@ -32116,15 +32118,14 @@
     final documentChangesJson = json['documentChanges'];
     final documentChanges = documentChangesJson == null
         ? null
-        : ((documentChangesJson is List &&
+        : ((documentChangesJson is List<Object?> &&
                 (documentChangesJson.every((item) =>
                     TextDocumentEdit.canParse(item, nullLspJsonReporter))))
-            ? Either2<List<TextDocumentEdit>, List<Either4<TextDocumentEdit, CreateFile, RenameFile, DeleteFile>>>.t1(
-                (documentChangesJson)
-                    .map((item) =>
-                        TextDocumentEdit.fromJson(item as Map<String, Object?>))
-                    .toList())
-            : ((documentChangesJson is List &&
+            ? Either2<List<TextDocumentEdit>, List<Either4<TextDocumentEdit, CreateFile, RenameFile, DeleteFile>>>.t1((documentChangesJson)
+                .map((item) =>
+                    TextDocumentEdit.fromJson(item as Map<String, Object?>))
+                .toList())
+            : ((documentChangesJson is List<Object?> &&
                     (documentChangesJson.every((item) =>
                         (TextDocumentEdit.canParse(item, nullLspJsonReporter) ||
                             CreateFile.canParse(item, nullLspJsonReporter) ||
@@ -32194,7 +32195,7 @@
             !((changes is Map &&
                 (changes.keys.every((item) =>
                     item is String &&
-                    changes.values.every((item) => (item is List &&
+                    changes.values.every((item) => (item is List<Object?> &&
                         (item.every((item) =>
                             TextEdit.canParse(item, reporter)))))))))) {
           reporter.reportError('must be of type Map<String, List<TextEdit>>');
@@ -32207,10 +32208,10 @@
       try {
         final documentChanges = obj['documentChanges'];
         if (documentChanges != null &&
-            !(((documentChanges is List &&
+            !(((documentChanges is List<Object?> &&
                     (documentChanges.every((item) =>
                         TextDocumentEdit.canParse(item, reporter)))) ||
-                (documentChanges is List &&
+                (documentChanges is List<Object?> &&
                     (documentChanges.every((item) =>
                         (TextDocumentEdit.canParse(item, reporter) ||
                             CreateFile.canParse(item, reporter) ||
@@ -32368,7 +32369,7 @@
       try {
         final resourceOperations = obj['resourceOperations'];
         if (resourceOperations != null &&
-            !((resourceOperations is List &&
+            !((resourceOperations is List<Object?> &&
                 (resourceOperations.every((item) =>
                     ResourceOperationKind.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<ResourceOperationKind>');
@@ -32642,7 +32643,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((added is List &&
+        if (!((added is List<Object?> &&
             (added
                 .every((item) => WorkspaceFolder.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<WorkspaceFolder>');
@@ -32662,7 +32663,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((removed is List &&
+        if (!((removed is List<Object?> &&
             (removed
                 .every((item) => WorkspaceFolder.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<WorkspaceFolder>');
@@ -32945,7 +32946,7 @@
       try {
         final valueSet = obj['valueSet'];
         if (valueSet != null &&
-            !((valueSet is List &&
+            !((valueSet is List<Object?> &&
                 (valueSet
                     .every((item) => SymbolKind.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<SymbolKind>');
@@ -33017,7 +33018,7 @@
           reporter.reportError('must not be null');
           return false;
         }
-        if (!((valueSet is List &&
+        if (!((valueSet is List<Object?> &&
             (valueSet.every((item) => SymbolTag.canParse(item, reporter)))))) {
           reporter.reportError('must be of type List<SymbolTag>');
           return false;
diff --git a/pkg/analysis_server/lib/plugin/edit/fix/fix_dart.dart b/pkg/analysis_server/lib/plugin/edit/fix/fix_dart.dart
index 3550b96..327a6e6 100644
--- a/pkg/analysis_server/lib/plugin/edit/fix/fix_dart.dart
+++ b/pkg/analysis_server/lib/plugin/edit/fix/fix_dart.dart
@@ -3,9 +3,8 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:analysis_server/plugin/edit/fix/fix_core.dart';
-import 'package:analysis_server/src/services/completion/dart/extension_cache.dart';
-import 'package:analysis_server/src/services/correction/fix/dart/top_level_declarations.dart';
 import 'package:analyzer/dart/analysis/results.dart';
+import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/instrumentation/service.dart';
 import 'package:analyzer_plugin/utilities/change_builder/change_workspace.dart';
 
@@ -13,9 +12,6 @@
 ///
 /// Clients may not extend, implement or mix-in this class.
 abstract class DartFixContext implements FixContext {
-  /// Return the extension cache used to find available extensions.
-  ExtensionCache get extensionCache;
-
   /// Return the instrumentation service used to report errors that prevent a
   /// fix from being composed.
   InstrumentationService get instrumentationService;
@@ -26,7 +22,13 @@
   /// The workspace in which the fix contributor operates.
   ChangeWorkspace get workspace;
 
-  /// Return top-level declarations with the [name] in libraries that are
-  /// available to this context.
-  List<TopLevelDeclaration> getTopLevelDeclarations(String name);
+  /// Return the mapping from a library (that is available to this context) to
+  /// a top-level declaration that is exported (not necessary declared) by this
+  /// library, and has the requested base name. For getters and setters the
+  /// corresponding top-level variable is returned.
+  Future<Map<LibraryElement, Element>> getTopLevelDeclarations(String name);
+
+  /// Return libraries with extensions that declare non-static public
+  /// extension members with the [memberName].
+  Stream<LibraryElement> librariesWithExtensions(String memberName);
 }
diff --git a/pkg/analysis_server/lib/protocol/protocol.dart b/pkg/analysis_server/lib/protocol/protocol.dart
index 263083a..3481a4c 100644
--- a/pkg/analysis_server/lib/protocol/protocol.dart
+++ b/pkg/analysis_server/lib/protocol/protocol.dart
@@ -8,6 +8,7 @@
 
 import 'package:analysis_server/protocol/protocol_generated.dart';
 import 'package:analysis_server/src/protocol/protocol_internal.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 
 export 'package:analyzer_plugin/protocol/protocol.dart' show Enum;
 
@@ -28,7 +29,7 @@
 
   /// A table mapping the names of notification parameters to their values, or
   /// `null` if there are no notification parameters.
-  final Map<String, Object>? params;
+  final Map<String, Object?>? params;
 
   /// Initialize a newly created [Notification] to have the given [event] name.
   /// If [params] is provided, it will be used as the params; otherwise no
@@ -38,7 +39,7 @@
   /// Initialize a newly created instance based on the given JSON data.
   factory Notification.fromJson(Map json) {
     return Notification(json[Notification.EVENT] as String,
-        json[Notification.PARAMS] as Map<String, Object>?);
+        json[Notification.PARAMS] as Map<String, Object?>?);
   }
 
   /// Return a table representing the structure of the Json object that will be
@@ -270,7 +271,7 @@
   /// this handler, return `null` so that other handlers will be given a chance
   /// to handle it. Otherwise, return the response that should be passed back to
   /// the client.
-  Response? handleRequest(Request request);
+  Response? handleRequest(Request request, CancellationToken cancellationToken);
 }
 
 /// A response to a request.
diff --git a/pkg/analysis_server/lib/protocol/protocol_constants.dart b/pkg/analysis_server/lib/protocol/protocol_constants.dart
index 85a4474..00b690a 100644
--- a/pkg/analysis_server/lib/protocol/protocol_constants.dart
+++ b/pkg/analysis_server/lib/protocol/protocol_constants.dart
@@ -6,7 +6,7 @@
 // To regenerate the file, use the script
 // "pkg/analysis_server/tool/spec/generate_files".
 
-const String PROTOCOL_VERSION = '1.32.7';
+const String PROTOCOL_VERSION = '1.32.8';
 
 const String ANALYSIS_NOTIFICATION_ANALYZED_FILES = 'analysis.analyzedFiles';
 const String ANALYSIS_NOTIFICATION_ANALYZED_FILES_DIRECTORIES = 'directories';
@@ -356,6 +356,8 @@
 const String SERVER_NOTIFICATION_STATUS = 'server.status';
 const String SERVER_NOTIFICATION_STATUS_ANALYSIS = 'analysis';
 const String SERVER_NOTIFICATION_STATUS_PUB = 'pub';
+const String SERVER_REQUEST_CANCEL_REQUEST = 'server.cancelRequest';
+const String SERVER_REQUEST_CANCEL_REQUEST_ID = 'id';
 const String SERVER_REQUEST_GET_VERSION = 'server.getVersion';
 const String SERVER_REQUEST_SET_SUBSCRIPTIONS = 'server.setSubscriptions';
 const String SERVER_REQUEST_SET_SUBSCRIPTIONS_SUBSCRIPTIONS = 'subscriptions';
diff --git a/pkg/analysis_server/lib/protocol/protocol_generated.dart b/pkg/analysis_server/lib/protocol/protocol_generated.dart
index bfdf408..8d9f921 100644
--- a/pkg/analysis_server/lib/protocol/protocol_generated.dart
+++ b/pkg/analysis_server/lib/protocol/protocol_generated.dart
@@ -15633,6 +15633,91 @@
       );
 }
 
+/// server.cancelRequest params
+///
+/// {
+///   "id": String
+/// }
+///
+/// Clients may not extend, implement or mix-in this class.
+class ServerCancelRequestParams implements RequestParams {
+  /// The id of the request that should be cancelled.
+  String id;
+
+  ServerCancelRequestParams(this.id);
+
+  factory ServerCancelRequestParams.fromJson(
+      JsonDecoder jsonDecoder, String jsonPath, Object? json) {
+    json ??= {};
+    if (json is Map) {
+      String id;
+      if (json.containsKey('id')) {
+        id = jsonDecoder.decodeString(jsonPath + '.id', json['id']);
+      } else {
+        throw jsonDecoder.mismatch(jsonPath, 'id');
+      }
+      return ServerCancelRequestParams(id);
+    } else {
+      throw jsonDecoder.mismatch(jsonPath, 'server.cancelRequest params', json);
+    }
+  }
+
+  factory ServerCancelRequestParams.fromRequest(Request request) {
+    return ServerCancelRequestParams.fromJson(
+        RequestDecoder(request), 'params', request.params);
+  }
+
+  @override
+  Map<String, Object> toJson() {
+    var result = <String, Object>{};
+    result['id'] = id;
+    return result;
+  }
+
+  @override
+  Request toRequest(String id) {
+    return Request(id, 'server.cancelRequest', toJson());
+  }
+
+  @override
+  String toString() => json.encode(toJson());
+
+  @override
+  bool operator ==(other) {
+    if (other is ServerCancelRequestParams) {
+      return id == other.id;
+    }
+    return false;
+  }
+
+  @override
+  int get hashCode => id.hashCode;
+}
+
+/// server.cancelRequest result
+///
+/// Clients may not extend, implement or mix-in this class.
+class ServerCancelRequestResult implements ResponseResult {
+  @override
+  Map<String, Object> toJson() => <String, Object>{};
+
+  @override
+  Response toResponse(String id) {
+    return Response(id, result: null);
+  }
+
+  @override
+  bool operator ==(other) {
+    if (other is ServerCancelRequestResult) {
+      return true;
+    }
+    return false;
+  }
+
+  @override
+  int get hashCode => 183255719;
+}
+
 /// server.connected params
 ///
 /// {
diff --git a/pkg/analysis_server/lib/src/analysis_server.dart b/pkg/analysis_server/lib/src/analysis_server.dart
index bbe634a..4c8b529 100644
--- a/pkg/analysis_server/lib/src/analysis_server.dart
+++ b/pkg/analysis_server/lib/src/analysis_server.dart
@@ -41,6 +41,7 @@
 import 'package:analysis_server/src/server/sdk_configuration.dart';
 import 'package:analysis_server/src/services/flutter/widget_descriptions.dart';
 import 'package:analysis_server/src/utilities/process.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analysis_server/src/utilities/request_statistics.dart';
 import 'package:analyzer/dart/analysis/results.dart';
 import 'package:analyzer/dart/ast/ast.dart';
@@ -81,6 +82,13 @@
   /// A set of the [ServerService]s to send notifications for.
   Set<ServerService> serverServices = HashSet<ServerService>();
 
+  /// A table mapping request ids to cancellation tokens that allow cancelling
+  /// the request.
+  ///
+  /// Tokens are removed once a request completes and should not be assumed to
+  /// exist in this table just because cancellation was requested.
+  Map<String, CancelableToken> cancellationTokens = {};
+
   /// A set of the [GeneralAnalysisService]s to send notifications for.
   Set<GeneralAnalysisService> generalAnalysisServices =
       HashSet<GeneralAnalysisService>();
@@ -219,6 +227,10 @@
     return sdkManager.defaultSdkDirectory;
   }
 
+  void cancelRequest(String id) {
+    cancellationTokens[id]?.cancel();
+  }
+
   /// The socket from which requests are being read has been closed.
   void done() {}
 
@@ -241,30 +253,32 @@
   void handleRequest(Request request) {
     performance.logRequestTiming(request.clientRequestTime);
     runZonedGuarded(() {
+      var cancellationToken = CancelableToken();
+      cancellationTokens[request.id] = cancellationToken;
       var count = handlers.length;
       for (var i = 0; i < count; i++) {
         try {
-          var response = handlers[i].handleRequest(request);
+          var response = handlers[i].handleRequest(request, cancellationToken);
           if (response == Response.DELAYED_RESPONSE) {
             return;
           }
           if (response != null) {
-            channel.sendResponse(response);
+            sendResponse(response);
             return;
           }
         } on RequestFailure catch (exception) {
-          channel.sendResponse(exception.response);
+          sendResponse(exception.response);
           return;
         } catch (exception, stackTrace) {
           var error =
               RequestError(RequestErrorCode.SERVER_ERROR, exception.toString());
           error.stackTrace = stackTrace.toString();
           var response = Response(request.id, error: error);
-          channel.sendResponse(response);
+          sendResponse(response);
           return;
         }
       }
-      channel.sendResponse(Response.unknownRequest(request));
+      sendResponse(Response.unknownRequest(request));
     }, (exception, stackTrace) {
       instrumentationService.logException(
         FatalException(
@@ -310,6 +324,7 @@
   /// Send the given [response] to the client.
   void sendResponse(Response response) {
     channel.sendResponse(response);
+    cancellationTokens.remove(response.id);
   }
 
   /// If the [path] is not a valid file path, that is absolute and normalized,
@@ -768,7 +783,6 @@
     var path = result.path;
 
     analysisServer.getDocumentationCacheFor(result)?.cacheFromResult(result);
-    analysisServer.getExtensionCacheFor(result)?.cacheFromResult(result);
 
     var unit = result.unit;
     if (analysisServer._hasAnalysisServiceSubscription(
diff --git a/pkg/analysis_server/lib/src/analysis_server_abstract.dart b/pkg/analysis_server/lib/src/analysis_server_abstract.dart
index 7724107..b94ee3f 100644
--- a/pkg/analysis_server/lib/src/analysis_server_abstract.dart
+++ b/pkg/analysis_server/lib/src/analysis_server_abstract.dart
@@ -15,7 +15,6 @@
 import 'package:analysis_server/src/server/crash_reporting_attachments.dart';
 import 'package:analysis_server/src/server/diagnostic_server.dart';
 import 'package:analysis_server/src/services/completion/dart/documentation_cache.dart';
-import 'package:analysis_server/src/services/completion/dart/extension_cache.dart';
 import 'package:analysis_server/src/services/correction/namespace.dart';
 import 'package:analysis_server/src/services/pub/pub_api.dart';
 import 'package:analysis_server/src/services/pub/pub_command.dart';
@@ -95,10 +94,6 @@
   /// each context.
   Map<AnalysisContext, DocumentationCache> documentationForContext = {};
 
-  /// A map from analysis contexts to the extension cache associated with
-  /// each context.
-  Map<AnalysisContext, ExtensionCache> extensionForContext = {};
-
   /// The DiagnosticServer for this AnalysisServer. If available, it can be used
   /// to start an http diagnostics server or return the port for an existing
   /// server.
@@ -252,7 +247,6 @@
   void addContextsToDeclarationsTracker() {
     declarationsTracker?.discardContexts();
     documentationForContext.clear();
-    extensionForContext.clear();
     for (var driver in driverMap.values) {
       declarationsTracker?.addContext(driver.analysisContext!);
     }
@@ -383,14 +377,6 @@
     return element;
   }
 
-  /// Return the object used to cache information about extensions in the
-  /// context that produced the [result], or `null` if there is no cache for the
-  /// context.
-  ExtensionCache? getExtensionCacheFor(ResolvedUnitResult result) {
-    var context = result.session.analysisContext;
-    return extensionForContext.putIfAbsent(context, () => ExtensionCache());
-  }
-
   /// Return a [Future] that completes with the resolved [AstNode] at the
   /// given [offset] of the given [file], or with `null` if there is no node as
   /// the [offset].
@@ -500,6 +486,7 @@
     } catch (e, st) {
       instrumentationService.logException(e, st);
     }
+    return null;
   }
 
   /// Sends an error notification to the user.
diff --git a/pkg/analysis_server/lib/src/cider/fixes.dart b/pkg/analysis_server/lib/src/cider/fixes.dart
index b3898bd..6b65f24 100644
--- a/pkg/analysis_server/lib/src/cider/fixes.dart
+++ b/pkg/analysis_server/lib/src/cider/fixes.dart
@@ -7,12 +7,14 @@
 import 'package:analysis_server/src/services/correction/fix.dart';
 import 'package:analysis_server/src/services/correction/fix/dart/top_level_declarations.dart';
 import 'package:analysis_server/src/services/correction/fix_internal.dart';
+import 'package:analyzer/dart/analysis/results.dart';
+import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/instrumentation/service.dart';
 import 'package:analyzer/source/line_info.dart';
 import 'package:analyzer/src/dart/analysis/performance_logger.dart';
-import 'package:analyzer/src/dart/micro/library_graph.dart' as cider;
 import 'package:analyzer/src/dart/micro/resolve_file.dart';
+import 'package:analyzer_plugin/utilities/change_builder/change_workspace.dart';
 
 class CiderErrorFixes {
   final AnalysisError error;
@@ -47,12 +49,11 @@
         var errorLine = lineInfo.getLocation(error.offset).lineNumber;
         if (errorLine == lineNumber) {
           var workspace = DartChangeWorkspace([resolvedUnit.session]);
-          var context = DartFixContextImpl(
-            InstrumentationService.NULL_SERVICE,
+          var context = _CiderDartFixContextImpl(
+            _fileResolver,
             workspace,
             resolvedUnit,
             error,
-            _topLevelDeclarations,
           );
 
           var fixes = await DartFixContributor().computeFixes(context);
@@ -67,33 +68,36 @@
 
     return result;
   }
+}
 
-  List<TopLevelDeclaration> _topLevelDeclarations(String name) {
-    var result = <TopLevelDeclaration>[];
+class _CiderDartFixContextImpl extends DartFixContextImpl {
+  final FileResolver _fileResolver;
+
+  _CiderDartFixContextImpl(
+    this._fileResolver,
+    ChangeWorkspace workspace,
+    ResolvedUnitResult resolvedUnit,
+    AnalysisError error,
+  ) : super(InstrumentationService.NULL_SERVICE, workspace, resolvedUnit,
+            error);
+
+  @override
+  Future<Map<LibraryElement, Element>> getTopLevelDeclarations(
+    String name,
+  ) async {
+    var result = <LibraryElement, Element>{};
     var files = _fileResolver.getFilesWithTopLevelDeclarations(name);
-    for (var fileWithKind in files) {
-      void addDeclaration(TopLevelDeclarationKind kind) {
-        var file = fileWithKind.file;
-        result.add(
-          TopLevelDeclaration(file.path, file.uri, kind, name, false),
+    for (var file in files) {
+      if (file.partOfLibrary == null) {
+        var libraryElement = _fileResolver.getLibraryByUri(
+          uriStr: file.uriStr,
         );
-      }
-
-      switch (fileWithKind.kind) {
-        case cider.FileTopLevelDeclarationKind.extension:
-          addDeclaration(TopLevelDeclarationKind.extension);
-          break;
-        case cider.FileTopLevelDeclarationKind.function:
-          addDeclaration(TopLevelDeclarationKind.function);
-          break;
-        case cider.FileTopLevelDeclarationKind.type:
-          addDeclaration(TopLevelDeclarationKind.type);
-          break;
-        case cider.FileTopLevelDeclarationKind.variable:
-          addDeclaration(TopLevelDeclarationKind.variable);
-          break;
+        TopLevelDeclarations.addElement(result, libraryElement, name);
       }
     }
     return result;
   }
+
+  @override
+  Stream<LibraryElement> librariesWithExtensions(String memberName) async* {}
 }
diff --git a/pkg/analysis_server/lib/src/cider/rename.dart b/pkg/analysis_server/lib/src/cider/rename.dart
index 4c38533..0b7a0fc 100644
--- a/pkg/analysis_server/lib/src/cider/rename.dart
+++ b/pkg/analysis_server/lib/src/cider/rename.dart
@@ -5,11 +5,13 @@
 import 'package:analysis_server/src/services/correction/status.dart';
 import 'package:analysis_server/src/services/refactoring/naming_conventions.dart';
 import 'package:analysis_server/src/services/refactoring/refactoring.dart';
+import 'package:analysis_server/src/utilities/flutter.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/source/line_info.dart';
 import 'package:analyzer/src/dart/ast/utilities.dart';
 import 'package:analyzer/src/dart/micro/resolve_file.dart';
 import 'package:analyzer/src/dart/micro/utils.dart';
+import 'package:analyzer/src/utilities/extensions/collection.dart';
 
 class CanRenameResponse {
   final LineInfo lineInfo;
@@ -17,6 +19,8 @@
   final FileResolver _fileResolver;
   final String filePath;
 
+  FlutterWidgetState? _flutterWidgetState;
+
   CanRenameResponse(this.lineInfo, this.refactoringElement, this._fileResolver,
       this.filePath);
 
@@ -24,6 +28,8 @@
 
   CheckNameResponse? checkNewName(String name) {
     var element = refactoringElement.element;
+    _flutterWidgetState = _findFlutterStateClass(element, name);
+
     RefactoringStatus? status;
     if (element is LocalVariableElement) {
       status = validateVariableName(name);
@@ -31,12 +37,36 @@
       status = validateParameterName(name);
     } else if (element is FunctionElement) {
       status = validateFunctionName(name);
-    }
-    if (status == null) {
+    } else if (element is TopLevelVariableElement) {
+      status = validateVariableName(name);
+    } else if (element is TypeAliasElement) {
+      status = validateTypeAliasName(name);
+    } else if (element is ClassElement) {
+      status = validateClassName(name);
+    } else if (status == null) {
       return null;
     }
     return CheckNameResponse(status, this);
   }
+
+  FlutterWidgetState? _findFlutterStateClass(Element element, String newName) {
+    if (Flutter.instance.isStatefulWidgetDeclaration(element)) {
+      var oldStateName = element.displayName + 'State';
+      var library = element.library!;
+      var state =
+          library.getType(oldStateName) ?? library.getType('_' + oldStateName);
+      if (state != null) {
+        var flutterWidgetStateNewName = newName + 'State';
+        // If the State was private, ensure that it stays private.
+        if (state.name.startsWith('_') &&
+            !flutterWidgetStateNewName.startsWith('_')) {
+          flutterWidgetStateNewName = '_' + flutterWidgetStateNewName;
+        }
+        return FlutterWidgetState(state, flutterWidgetStateNewName);
+      }
+    }
+    return null;
+  }
 }
 
 class CheckNameResponse {
@@ -50,9 +80,29 @@
   String get oldName => canRename.refactoringElement.element.displayName;
 
   RenameResponse? computeRenameRanges() {
-    var matches = canRename._fileResolver
-        .findReferences(canRename.refactoringElement.element);
-    return RenameResponse(matches, this);
+    var elements = <Element>[];
+    var element = canRename.refactoringElement.element;
+    if (element is PropertyInducingElement && element.isSynthetic) {
+      var property = element;
+      var getter = property.getter;
+      var setter = property.setter;
+      elements.addIfNotNull(getter);
+      elements.addIfNotNull(setter);
+    } else {
+      elements.add(element);
+    }
+    var matches = <CiderSearchMatch>[];
+    for (var element in elements) {
+      matches.addAll(canRename._fileResolver.findReferences(element));
+    }
+
+    FlutterWidgetRename? flutterRename;
+    if (canRename._flutterWidgetState != null) {
+      var stateWidget = canRename._flutterWidgetState!;
+      var match = canRename._fileResolver.findReferences(stateWidget.state);
+      flutterRename = FlutterWidgetRename(stateWidget.newName, match);
+    }
+    return RenameResponse(matches, this, flutterWidgetRename: flutterRename);
   }
 }
 
@@ -80,6 +130,9 @@
     if (element is MethodElement && element.isOperator) {
       return null;
     }
+    if (element is PropertyAccessorElement) {
+      element = element.variable;
+    }
     if (!_canRenameElement(element)) {
       return null;
     }
@@ -90,59 +143,43 @@
     return null;
   }
 
-  @deprecated
-  CheckNameResponse? checkNewName(
-      String filePath, int line, int column, String name) {
-    var resolvedUnit = _fileResolver.resolve(path: filePath);
-    var lineInfo = resolvedUnit.lineInfo;
-    var offset = lineInfo.getOffsetOfLine(line) + column;
-
-    var node = NodeLocator(offset).searchWithin(resolvedUnit.unit);
-    var element = getElementOfNode(node);
-
-    if (node == null || element == null) {
-      return null;
-    }
-
-    var refactoring = RenameRefactoring.getElementToRename(node, element);
-    if (refactoring == null) {
-      return null;
-    }
-    RefactoringStatus? status;
-    if (element is LocalVariableElement) {
-      status = validateVariableName(name);
-    } else if (element is ParameterElement) {
-      status = validateParameterName(name);
-    } else if (element is FunctionElement) {
-      status = validateFunctionName(name);
-    }
-    if (status == null) {
-      return null;
-    }
-
-    return CheckNameResponse(status,
-        CanRenameResponse(lineInfo, refactoring, _fileResolver, filePath));
-  }
-
   bool _canRenameElement(Element element) {
-    if (element is PropertyAccessorElement) {
-      element = element.variable;
-    }
     var enclosingElement = element.enclosingElement;
+    if (element is ConstructorElement) {
+      return false;
+    }
     if (element is LabelElement || element is LocalElement) {
       return true;
     }
     if (enclosingElement is ClassElement ||
-        enclosingElement is ExtensionElement) {
+        enclosingElement is ExtensionElement ||
+        enclosingElement is CompilationUnitElement) {
       return true;
     }
+
     return false;
   }
 }
 
+class FlutterWidgetRename {
+  final String name;
+  final List<CiderSearchMatch> matches;
+
+  FlutterWidgetRename(this.name, this.matches);
+}
+
+/// The corresponding `State` declaration of a  Flutter `StatefulWidget`.
+class FlutterWidgetState {
+  ClassElement state;
+  String newName;
+
+  FlutterWidgetState(this.state, this.newName);
+}
+
 class RenameResponse {
   final List<CiderSearchMatch> matches;
   final CheckNameResponse checkName;
+  FlutterWidgetRename? flutterWidgetRename;
 
-  RenameResponse(this.matches, this.checkName);
+  RenameResponse(this.matches, this.checkName, {this.flutterWidgetRename});
 }
diff --git a/pkg/analysis_server/lib/src/cider/signature_help.dart b/pkg/analysis_server/lib/src/cider/signature_help.dart
new file mode 100644
index 0000000..6b3616a
--- /dev/null
+++ b/pkg/analysis_server/lib/src/cider/signature_help.dart
@@ -0,0 +1,56 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analysis_server/lsp_protocol/protocol_generated.dart';
+import 'package:analysis_server/src/computer/computer_signature.dart';
+import 'package:analysis_server/src/computer/computer_type_arguments_signature.dart';
+import 'package:analysis_server/src/lsp/mapping.dart';
+import 'package:analyzer/source/line_info.dart';
+import 'package:analyzer/src/dart/micro/resolve_file.dart';
+import 'package:analyzer/src/dartdoc/dartdoc_directive_info.dart';
+
+class CiderSignatureHelpComputer {
+  final FileResolver _fileResolver;
+
+  CiderSignatureHelpComputer(this._fileResolver);
+
+  SignatureHelpResponse? compute(String filePath, int line, int column) {
+    var resolvedUnit = _fileResolver.resolve(path: filePath);
+    var lineInfo = resolvedUnit.lineInfo;
+    var offset = lineInfo.getOffsetOfLine(line) + column;
+    final formats = <MarkupKind>{MarkupKind.Markdown};
+
+    var dartDocInfo = DartdocDirectiveInfo();
+    final typeArgsComputer = DartTypeArgumentsSignatureComputer(
+        dartDocInfo, resolvedUnit.unit, offset, formats);
+    if (typeArgsComputer.offsetIsValid) {
+      final typeSignature = typeArgsComputer.compute();
+
+      if (typeSignature != null) {
+        return SignatureHelpResponse(typeSignature,
+            lineInfo.getLocation(typeArgsComputer.argumentList.offset + 1));
+      }
+    }
+
+    final computer =
+        DartUnitSignatureComputer(dartDocInfo, resolvedUnit.unit, offset);
+    if (computer.offsetIsValid) {
+      final signature = computer.compute();
+      if (signature != null) {
+        return SignatureHelpResponse(toSignatureHelp(formats, signature),
+            lineInfo.getLocation(computer.argumentList.offset + 1));
+      }
+    }
+    return null;
+  }
+}
+
+class SignatureHelpResponse {
+  final SignatureHelp signatureHelp;
+
+  /// The location of the left parenthesis.
+  final CharacterLocation callStart;
+
+  SignatureHelpResponse(this.signatureHelp, this.callStart);
+}
diff --git a/pkg/analysis_server/lib/src/computer/computer_color.dart b/pkg/analysis_server/lib/src/computer/computer_color.dart
index 56352d1..1026b0a 100644
--- a/pkg/analysis_server/lib/src/computer/computer_color.dart
+++ b/pkg/analysis_server/lib/src/computer/computer_color.dart
@@ -173,6 +173,8 @@
       return alpha != null && red != null && green != null && blue != null
           ? _colorValueForComponents(alpha, red, green, blue)
           : null;
+    } else {
+      return null;
     }
   }
 
@@ -187,6 +189,8 @@
     if (name == null && args.isNotEmpty) {
       final arg0 = args[0];
       return arg0 is IntegerLiteral ? arg0.value : null;
+    } else {
+      return null;
     }
   }
 
@@ -208,6 +212,8 @@
         return _getSwatchValue(target, shadeNumber);
       }
     }
+
+    return null;
   }
 
   /// Extracts a specific shade index from a Flutter SwatchColor.
diff --git a/pkg/analysis_server/lib/src/context_manager.dart b/pkg/analysis_server/lib/src/context_manager.dart
index b6df480..ceb6b14 100644
--- a/pkg/analysis_server/lib/src/context_manager.dart
+++ b/pkg/analysis_server/lib/src/context_manager.dart
@@ -15,7 +15,6 @@
 import 'package:analyzer/src/dart/analysis/driver_based_analysis_context.dart';
 import 'package:analyzer/src/dart/analysis/file_content_cache.dart';
 import 'package:analyzer/src/dart/analysis/performance_logger.dart';
-import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/lint/linter.dart';
@@ -279,7 +278,7 @@
     var convertedErrors = const <protocol.AnalysisError>[];
     try {
       var content = _readFile(path);
-      var lineInfo = _computeLineInfo(content);
+      var lineInfo = LineInfo.fromContent(content);
       var errors = analyzeAnalysisOptions(
         resourceProvider.getFile(path).createSource(),
         content,
@@ -304,7 +303,7 @@
       var content = _readFile(path);
       var validator =
           ManifestValidator(resourceProvider.getFile(path).createSource());
-      var lineInfo = _computeLineInfo(content);
+      var lineInfo = LineInfo.fromContent(content);
       var errors = validator.validate(
           content, driver.analysisOptions.chromeOsManifestChecks);
       var converter = AnalyzerConverter();
@@ -331,7 +330,8 @@
       parser.parse(content);
       var converter = AnalyzerConverter();
       convertedErrors = converter.convertAnalysisErrors(errorListener.errors,
-          lineInfo: _computeLineInfo(content), options: driver.analysisOptions);
+          lineInfo: LineInfo.fromContent(content),
+          options: driver.analysisOptions);
     } catch (exception) {
       // If the file cannot be analyzed, fall through to clear any previous
       // errors.
@@ -349,7 +349,7 @@
       if (node is YamlMap) {
         var validator = PubspecValidator(
             resourceProvider, resourceProvider.getFile(path).createSource());
-        var lineInfo = _computeLineInfo(content);
+        var lineInfo = LineInfo.fromContent(content);
         var errors = validator.validate(node.nodes);
         var converter = AnalyzerConverter();
         convertedErrors = converter.convertAnalysisErrors(errors,
@@ -412,12 +412,6 @@
     }
   }
 
-  /// Compute line information for the given [content].
-  LineInfo _computeLineInfo(String content) {
-    var lineStarts = StringUtilities.computeLineStarts(content);
-    return LineInfo(lineStarts);
-  }
-
   void _createAnalysisContexts() {
     _destroyAnalysisContexts();
     _fileContentCache.invalidateAll();
diff --git a/pkg/analysis_server/lib/src/domain_analysis.dart b/pkg/analysis_server/lib/src/domain_analysis.dart
index 1595e38..d079a6b 100644
--- a/pkg/analysis_server/lib/src/domain_analysis.dart
+++ b/pkg/analysis_server/lib/src/domain_analysis.dart
@@ -13,6 +13,7 @@
 import 'package:analysis_server/src/plugin/result_merger.dart';
 import 'package:analysis_server/src/protocol/protocol_internal.dart';
 import 'package:analysis_server/src/protocol_server.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/dart/analysis/results.dart';
 import 'package:analyzer/src/generated/engine.dart' as engine;
 import 'package:analyzer_plugin/protocol/protocol_generated.dart' as plugin;
@@ -254,7 +255,8 @@
   }
 
   @override
-  Response? handleRequest(Request request) {
+  Response? handleRequest(
+      Request request, CancellationToken cancellationToken) {
     try {
       var requestName = request.method;
       if (requestName == ANALYSIS_REQUEST_GET_ERRORS) {
diff --git a/pkg/analysis_server/lib/src/domain_analytics.dart b/pkg/analysis_server/lib/src/domain_analytics.dart
index 66df103..cec9fa8 100644
--- a/pkg/analysis_server/lib/src/domain_analytics.dart
+++ b/pkg/analysis_server/lib/src/domain_analytics.dart
@@ -6,6 +6,7 @@
 import 'package:analysis_server/protocol/protocol_constants.dart';
 import 'package:analysis_server/protocol/protocol_generated.dart';
 import 'package:analysis_server/src/analysis_server.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:telemetry/telemetry.dart';
 
 /// Instances of the class [AnalyticsDomainHandler] implement a [RequestHandler]
@@ -34,7 +35,8 @@
   }
 
   @override
-  Response? handleRequest(Request request) {
+  Response? handleRequest(
+      Request request, CancellationToken cancellationToken) {
     var requestName = request.method;
 
     if (requestName == ANALYTICS_REQUEST_IS_ENABLED) {
diff --git a/pkg/analysis_server/lib/src/domain_completion.dart b/pkg/analysis_server/lib/src/domain_completion.dart
index 60c81b6..661049b 100644
--- a/pkg/analysis_server/lib/src/domain_completion.dart
+++ b/pkg/analysis_server/lib/src/domain_completion.dart
@@ -22,6 +22,7 @@
 import 'package:analysis_server/src/services/completion/yaml/fix_data_generator.dart';
 import 'package:analysis_server/src/services/completion/yaml/pubspec_generator.dart';
 import 'package:analysis_server/src/services/completion/yaml/yaml_completion_generator.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/dart/analysis/session.dart';
 import 'package:analyzer/exception/exception.dart';
 import 'package:analyzer/src/generated/engine.dart';
@@ -425,7 +426,8 @@
   }
 
   @override
-  Response? handleRequest(Request request) {
+  Response? handleRequest(
+      Request request, CancellationToken cancellationToken) {
     if (!server.options.featureSet.completion) {
       return Response.invalidParameter(
         request,
@@ -516,8 +518,7 @@
 
         var resolvedUnit = await server.getResolvedUnit(file);
         if (resolvedUnit == null) {
-          server
-              .sendResponse(Response.fileNotAnalyzed(request, 'params.offset'));
+          server.sendResponse(Response.fileNotAnalyzed(request, file));
           return;
         }
 
diff --git a/pkg/analysis_server/lib/src/domain_diagnostic.dart b/pkg/analysis_server/lib/src/domain_diagnostic.dart
index 59056f2..117bec4 100644
--- a/pkg/analysis_server/lib/src/domain_diagnostic.dart
+++ b/pkg/analysis_server/lib/src/domain_diagnostic.dart
@@ -6,6 +6,7 @@
 import 'package:analysis_server/protocol/protocol_constants.dart';
 import 'package:analysis_server/protocol/protocol_generated.dart';
 import 'package:analysis_server/src/analysis_server.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/src/dart/analysis/driver.dart';
 
 /// Instances of the class [DiagnosticDomainHandler] implement a
@@ -45,7 +46,8 @@
   }
 
   @override
-  Response? handleRequest(Request request) {
+  Response? handleRequest(
+      Request request, CancellationToken cancellationToken) {
     try {
       var requestName = request.method;
       if (requestName == DIAGNOSTIC_REQUEST_GET_DIAGNOSTICS) {
diff --git a/pkg/analysis_server/lib/src/domain_execution.dart b/pkg/analysis_server/lib/src/domain_execution.dart
index 5550f0b..c1e1b35 100644
--- a/pkg/analysis_server/lib/src/domain_execution.dart
+++ b/pkg/analysis_server/lib/src/domain_execution.dart
@@ -7,6 +7,7 @@
 import 'package:analysis_server/protocol/protocol_constants.dart';
 import 'package:analysis_server/src/analysis_server.dart';
 import 'package:analysis_server/src/protocol_server.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/file_system/file_system.dart';
 
 /// Instances of the class [ExecutionDomainHandler] implement a [RequestHandler]
@@ -68,7 +69,8 @@
   }
 
   @override
-  Response? handleRequest(Request request) {
+  Response? handleRequest(
+      Request request, CancellationToken cancellationToken) {
     try {
       var requestName = request.method;
       if (requestName == EXECUTION_REQUEST_CREATE_CONTEXT) {
diff --git a/pkg/analysis_server/lib/src/domain_kythe.dart b/pkg/analysis_server/lib/src/domain_kythe.dart
index 0316e8f..0be62d1 100644
--- a/pkg/analysis_server/lib/src/domain_kythe.dart
+++ b/pkg/analysis_server/lib/src/domain_kythe.dart
@@ -9,6 +9,7 @@
 import 'package:analysis_server/src/domain_abstract.dart';
 import 'package:analysis_server/src/plugin/result_merger.dart';
 import 'package:analysis_server/src/services/kythe/kythe_visitors.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/src/dart/element/inheritance_manager3.dart';
 import 'package:analyzer_plugin/protocol/protocol_common.dart';
 import 'package:analyzer_plugin/protocol/protocol_generated.dart' as plugin;
@@ -70,7 +71,8 @@
   }
 
   @override
-  Response? handleRequest(Request request) {
+  Response? handleRequest(
+      Request request, CancellationToken cancellationToken) {
     try {
       var requestName = request.method;
       if (requestName == KYTHE_REQUEST_GET_KYTHE_ENTRIES) {
diff --git a/pkg/analysis_server/lib/src/domain_server.dart b/pkg/analysis_server/lib/src/domain_server.dart
index 559f3b8..54efa9a 100644
--- a/pkg/analysis_server/lib/src/domain_server.dart
+++ b/pkg/analysis_server/lib/src/domain_server.dart
@@ -6,6 +6,7 @@
 import 'package:analysis_server/protocol/protocol_constants.dart';
 import 'package:analysis_server/protocol/protocol_generated.dart';
 import 'package:analysis_server/src/analysis_server.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 
 /// Instances of the class [ServerDomainHandler] implement a [RequestHandler]
 /// that handles requests in the server domain.
@@ -17,6 +18,13 @@
   /// [server].
   ServerDomainHandler(this.server);
 
+  Response cancelRequest(Request request) {
+    final id = ServerCancelRequestParams.fromRequest(request).id;
+    server.cancelRequest(id);
+
+    return ServerCancelRequestResult().toResponse(request.id);
+  }
+
   /// Return the version number of the analysis server.
   Response getVersion(Request request) {
     return ServerGetVersionResult(
@@ -25,7 +33,8 @@
   }
 
   @override
-  Response? handleRequest(Request request) {
+  Response? handleRequest(
+      Request request, CancellationToken cancellationToken) {
     try {
       var requestName = request.method;
       if (requestName == SERVER_REQUEST_GET_VERSION) {
@@ -35,6 +44,8 @@
       } else if (requestName == SERVER_REQUEST_SHUTDOWN) {
         shutdown(request);
         return Response.DELAYED_RESPONSE;
+      } else if (requestName == SERVER_REQUEST_CANCEL_REQUEST) {
+        return cancelRequest(request);
       }
     } on RequestFailure catch (exception) {
       return exception.response;
diff --git a/pkg/analysis_server/lib/src/edit/edit_domain.dart b/pkg/analysis_server/lib/src/edit/edit_domain.dart
index b73448c..655d9d9 100644
--- a/pkg/analysis_server/lib/src/edit/edit_domain.dart
+++ b/pkg/analysis_server/lib/src/edit/edit_domain.dart
@@ -23,7 +23,6 @@
 import 'package:analysis_server/src/services/correction/change_workspace.dart';
 import 'package:analysis_server/src/services/correction/fix.dart';
 import 'package:analysis_server/src/services/correction/fix/analysis_options/fix_generator.dart';
-import 'package:analysis_server/src/services/correction/fix/dart/top_level_declarations.dart';
 import 'package:analysis_server/src/services/correction/fix/manifest/fix_generator.dart';
 import 'package:analysis_server/src/services/correction/fix/pubspec/fix_generator.dart';
 import 'package:analysis_server/src/services/correction/fix_internal.dart';
@@ -32,6 +31,7 @@
 import 'package:analysis_server/src/services/correction/status.dart';
 import 'package:analysis_server/src/services/refactoring/refactoring.dart';
 import 'package:analysis_server/src/services/search/search_engine.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/dart/analysis/session.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/error/error.dart' as engine;
@@ -337,7 +337,8 @@
   }
 
   @override
-  Response? handleRequest(Request request) {
+  Response? handleRequest(
+      Request request, CancellationToken cancellationToken) {
     try {
       var requestName = request.method;
       if (requestName == EDIT_REQUEST_FORMAT) {
@@ -534,7 +535,7 @@
       return;
     }
     // Do sort.
-    var sorter = MemberSorter(code, unit);
+    var sorter = MemberSorter(code, unit, result.lineInfo);
     var edits = sorter.sort();
     var fileEdit = SourceFileEdit(file, fileStamp, edits: edits);
     server.sendResponse(EditSortMembersResult(fileEdit).toResponse(request.id));
@@ -602,18 +603,7 @@
         if (errorLine == requestLine) {
           var workspace = DartChangeWorkspace(server.currentSessions);
           var context = DartFixContextImpl(
-              server.instrumentationService, workspace, result, error, (name) {
-            var tracker = server.declarationsTracker;
-            if (tracker == null) {
-              return const [];
-            }
-            var provider = TopLevelDeclarationsProvider(tracker);
-            return provider.get(
-              result.session.analysisContext,
-              result.path,
-              name,
-            );
-          }, extensionCache: server.getExtensionCacheFor(result));
+              server.instrumentationService, workspace, result, error);
 
           List<Fix> fixes;
           try {
diff --git a/pkg/analysis_server/lib/src/flutter/flutter_domain.dart b/pkg/analysis_server/lib/src/flutter/flutter_domain.dart
index 6ec33cc..66bce33 100644
--- a/pkg/analysis_server/lib/src/flutter/flutter_domain.dart
+++ b/pkg/analysis_server/lib/src/flutter/flutter_domain.dart
@@ -7,6 +7,7 @@
 import 'package:analysis_server/src/domain_abstract.dart';
 import 'package:analysis_server/src/protocol/protocol_internal.dart';
 import 'package:analysis_server/src/protocol_server.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/dart/analysis/session.dart';
 
 /// A [RequestHandler] that handles requests in the `flutter` domain.
@@ -71,7 +72,8 @@
   }
 
   @override
-  Response? handleRequest(Request request) {
+  Response? handleRequest(
+      Request request, CancellationToken cancellationToken) {
     try {
       var requestName = request.method;
       if (requestName == FLUTTER_REQUEST_GET_WIDGET_DESCRIPTION) {
diff --git a/pkg/analysis_server/lib/src/g3/fixes.dart b/pkg/analysis_server/lib/src/g3/fixes.dart
index 51c05f4..17f045c 100644
--- a/pkg/analysis_server/lib/src/g3/fixes.dart
+++ b/pkg/analysis_server/lib/src/g3/fixes.dart
@@ -96,7 +96,6 @@
       workspace,
       unitResult,
       error,
-      (name) => const [],
     );
 
     List<Fix> fixes;
diff --git a/pkg/analysis_server/lib/src/lsp/handlers/commands/sort_members.dart b/pkg/analysis_server/lib/src/lsp/handlers/commands/sort_members.dart
index d832d06..a4c2286 100644
--- a/pkg/analysis_server/lib/src/lsp/handlers/commands/sort_members.dart
+++ b/pkg/analysis_server/lib/src/lsp/handlers/commands/sort_members.dart
@@ -61,7 +61,7 @@
       ));
     }
 
-    final sorter = MemberSorter(code, unit);
+    final sorter = MemberSorter(code, unit, result.lineInfo);
     final edits = sorter.sort();
 
     if (edits.isEmpty) {
diff --git a/pkg/analysis_server/lib/src/lsp/handlers/handler_code_actions.dart b/pkg/analysis_server/lib/src/lsp/handlers/handler_code_actions.dart
index ecc14cc..521927d 100644
--- a/pkg/analysis_server/lib/src/lsp/handlers/handler_code_actions.dart
+++ b/pkg/analysis_server/lib/src/lsp/handlers/handler_code_actions.dart
@@ -14,7 +14,6 @@
 import 'package:analysis_server/src/services/correction/assist_internal.dart';
 import 'package:analysis_server/src/services/correction/change_workspace.dart';
 import 'package:analysis_server/src/services/correction/fix.dart';
-import 'package:analysis_server/src/services/correction/fix/dart/top_level_declarations.dart';
 import 'package:analysis_server/src/services/correction/fix_internal.dart';
 import 'package:analysis_server/src/services/refactoring/refactoring.dart';
 import 'package:analyzer/dart/analysis/results.dart';
@@ -347,14 +346,7 @@
         }
         var workspace = DartChangeWorkspace(server.currentSessions);
         var context = DartFixContextImpl(
-            server.instrumentationService, workspace, unit, error, (name) {
-          var tracker = server.declarationsTracker!;
-          return TopLevelDeclarationsProvider(tracker).get(
-            unit.session.analysisContext,
-            unit.path,
-            name,
-          );
-        }, extensionCache: server.getExtensionCacheFor(unit));
+            server.instrumentationService, workspace, unit, error);
         final fixes = await fixContributor.computeFixes(context);
         if (fixes.isNotEmpty) {
           final diagnostic = toDiagnostic(
diff --git a/pkg/analysis_server/lib/src/lsp/handlers/handler_completion.dart b/pkg/analysis_server/lib/src/lsp/handlers/handler_completion.dart
index 10e4cf9..d2bd74d 100644
--- a/pkg/analysis_server/lib/src/lsp/handlers/handler_completion.dart
+++ b/pkg/analysis_server/lib/src/lsp/handlers/handler_completion.dart
@@ -65,8 +65,9 @@
     final unit = await path.mapResult(requireResolvedUnit);
 
     final lineInfo = await unit.map(
-      // If we don't have a unit, we can still try to obtain the line info for
-      // plugin contributors.
+      // If we don't have a unit, we can still try to obtain the line info from
+      // the server (this could be because the file is non-Dart, such as YAML or
+      // another handled by a plugin).
       (error) => path.mapResult(getLineInfo),
       (unit) => success(unit.lineInfo),
     );
diff --git a/pkg/analysis_server/lib/src/lsp/handlers/handlers.dart b/pkg/analysis_server/lib/src/lsp/handlers/handlers.dart
index 6b2ed52..e0f497c 100644
--- a/pkg/analysis_server/lib/src/lsp/handlers/handlers.dart
+++ b/pkg/analysis_server/lib/src/lsp/handlers/handlers.dart
@@ -14,11 +14,14 @@
 import 'package:analysis_server/src/lsp/json_parsing.dart';
 import 'package:analysis_server/src/lsp/lsp_analysis_server.dart';
 import 'package:analysis_server/src/lsp/progress.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/dart/analysis/results.dart';
 import 'package:analyzer/source/line_info.dart';
 import 'package:analyzer_plugin/protocol/protocol.dart';
 import 'package:analyzer_plugin/src/protocol/protocol_internal.dart';
 
+export 'package:analysis_server/src/utilities/progress.dart';
+
 /// Converts an iterable using the provided function and skipping over any
 /// null values.
 Iterable<T> convert<T, E>(Iterable<E> items, T Function(E) converter) {
@@ -27,22 +30,6 @@
   return items.map(converter).where((item) => item != null);
 }
 
-class CancelableToken extends CancellationToken {
-  bool _isCancelled = false;
-
-  @override
-  bool get isCancellationRequested => _isCancelled;
-
-  void cancel() => _isCancelled = true;
-}
-
-/// A token used to signal cancellation of an operation. This allows computation
-/// to be skipped when a caller is no longer interested in the result, for example
-/// when a $/cancel request is recieved for an in-progress request.
-abstract class CancellationToken {
-  bool get isCancellationRequested;
-}
-
 abstract class CommandHandler<P, R> with Handler<P, R> {
   @override
   final LspAnalysisServer server;
@@ -151,11 +138,6 @@
   }
 }
 
-class NotCancelableToken extends CancellationToken {
-  @override
-  bool get isCancellationRequested => false;
-}
-
 /// A message handler that handles all messages for a given server state.
 abstract class ServerStateMessageHandler {
   final LspAnalysisServer server;
diff --git a/pkg/analysis_server/lib/src/lsp/lsp_analysis_server.dart b/pkg/analysis_server/lib/src/lsp/lsp_analysis_server.dart
index cf22460..e4e8d17 100644
--- a/pkg/analysis_server/lib/src/lsp/lsp_analysis_server.dart
+++ b/pkg/analysis_server/lib/src/lsp/lsp_analysis_server.dart
@@ -261,12 +261,23 @@
     capabilitiesComputer.performDynamicRegistration();
   }
 
-  /// Return the LineInfo for the file with the given [path]. The file is
-  /// analyzed in one of the analysis drivers to which the file was added,
-  /// otherwise in the first driver, otherwise `null` is returned.
+  /// Return a [LineInfo] for the file with the given [path].
+  ///
+  /// If the file does not exist or cannot be read, returns `null`.
+  ///
+  /// This method supports non-Dart files but uses the current content of the
+  /// file which may not be the latest analyzed version of the file if it was
+  /// recently modified, so using the lineInfo from an analyzed result may be
+  /// preferable.
   LineInfo? getLineInfo(String path) {
-    var result = getAnalysisDriver(path)?.getFileSync(path);
-    return result is FileResult ? result.lineInfo : null;
+    try {
+      final content = resourceProvider.getFile(path).readAsStringSync();
+      return LineInfo.fromContent(content);
+    } on FileSystemException {
+      // If the file does not exist or cannot be read, return null to allow
+      // the caller to decide how to handle this.
+      return null;
+    }
   }
 
   /// Gets the version of a document known to the server, returning a
@@ -896,7 +907,6 @@
     var path = result.path;
 
     analysisServer.getDocumentationCacheFor(result)?.cacheFromResult(result);
-    analysisServer.getExtensionCacheFor(result)?.cacheFromResult(result);
 
     final unit = result.unit;
     if (analysisServer.shouldSendClosingLabelsFor(path)) {
diff --git a/pkg/analysis_server/lib/src/lsp/mapping.dart b/pkg/analysis_server/lib/src/lsp/mapping.dart
index ffabd19..8a26c20 100644
--- a/pkg/analysis_server/lib/src/lsp/mapping.dart
+++ b/pkg/analysis_server/lib/src/lsp/mapping.dart
@@ -23,6 +23,7 @@
 import 'package:analyzer/dart/analysis/results.dart' as server;
 import 'package:analyzer/error/error.dart' as server;
 import 'package:analyzer/source/line_info.dart' as server;
+import 'package:analyzer/source/line_info.dart';
 import 'package:analyzer/source/source_range.dart' as server;
 import 'package:analyzer/src/dart/analysis/search.dart' as server
     show DeclarationKind;
@@ -123,8 +124,11 @@
       edits
           .map((e) => FileEditInformation(
                 server.getVersionedDocumentIdentifier(e.file),
-                // We should never produce edits for a file with no LineInfo.
-                server.getLineInfo(e.file)!,
+                // If we expect to create the file, server.getLineInfo() won't
+                // provide a LineInfo so create one from empty contents.
+                e.fileStamp == -1
+                    ? LineInfo.fromContent('')
+                    : server.getLineInfo(e.file)!,
                 e.edits,
                 // fileStamp == 1 is used by the server to indicate the file needs creating.
                 newFile: e.fileStamp == -1,
diff --git a/pkg/analysis_server/lib/src/lsp/server_capabilities_computer.dart b/pkg/analysis_server/lib/src/lsp/server_capabilities_computer.dart
index 5a009f5..0b28c2c 100644
--- a/pkg/analysis_server/lib/src/lsp/server_capabilities_computer.dart
+++ b/pkg/analysis_server/lib/src/lsp/server_capabilities_computer.dart
@@ -537,30 +537,43 @@
       ..removeAll(registrationsToRemove)
       ..addAll(registrationsToAdd);
 
+    Future<void>? unregistrationRequest;
     if (registrationsToRemove.isNotEmpty) {
       final unregistrations = registrationsToRemove
           .map((r) => Unregistration(id: r.id, method: r.method))
           .toList();
-      await _server.sendRequest(Method.client_unregisterCapability,
+      // It's important not to await this request here, as we must ensure
+      // we cannot re-enter this method until we have sent both the unregister
+      // and register requests to the client atomically.
+      // https://github.com/dart-lang/sdk/issues/47851#issuecomment-988093109
+      unregistrationRequest = _server.sendRequest(
+          Method.client_unregisterCapability,
           UnregistrationParams(unregisterations: unregistrations));
     }
 
+    Future<void>? registrationRequest;
     // Only send the registration request if we have at least one (since
     // otherwise we don't know that the client supports registerCapability).
     if (registrationsToAdd.isNotEmpty) {
-      final registrationResponse = await _server.sendRequest(
-        Method.client_registerCapability,
-        RegistrationParams(registrations: registrationsToAdd),
-      );
-
-      final error = registrationResponse.error;
-      if (error != null) {
-        _server.logErrorToClient(
-          'Failed to register capabilities with client: '
-          '(${error.code}) '
-          '${error.message}',
-        );
-      }
+      registrationRequest = _server
+          .sendRequest(Method.client_registerCapability,
+              RegistrationParams(registrations: registrationsToAdd))
+          .then((registrationResponse) {
+        final error = registrationResponse.error;
+        if (error != null) {
+          _server.logErrorToClient(
+            'Failed to register capabilities with client: '
+            '(${error.code}) '
+            '${error.message}',
+          );
+        }
+      });
     }
+
+    // Only after we have sent both unregistration + registration events may
+    // we await them, knowing another "thread" could not have executed this
+    // method between them.
+    await unregistrationRequest;
+    await registrationRequest;
   }
 }
diff --git a/pkg/analysis_server/lib/src/plugin/plugin_manager.dart b/pkg/analysis_server/lib/src/plugin/plugin_manager.dart
index 5972a14..fa6eee9 100644
--- a/pkg/analysis_server/lib/src/plugin/plugin_manager.dart
+++ b/pkg/analysis_server/lib/src/plugin/plugin_manager.dart
@@ -743,7 +743,7 @@
         sourceUrl: pubspecFile.toUri());
     var contents = document.contents;
     if (contents is YamlMap) {
-      YamlNode dependencies = contents['dependencies'];
+      var dependencies = contents['dependencies'] as YamlNode?;
       if (dependencies is YamlMap) {
         return dependencies.keys.cast<String>();
       }
diff --git a/pkg/analysis_server/lib/src/plugin/result_merger.dart b/pkg/analysis_server/lib/src/plugin/result_merger.dart
index 6e1257a..e8e51f3 100644
--- a/pkg/analysis_server/lib/src/plugin/result_merger.dart
+++ b/pkg/analysis_server/lib/src/plugin/result_merger.dart
@@ -239,9 +239,9 @@
     /// Return the index of the region in the collection of [mergedRegions] that
     /// covers exactly the same region as the [newRegion], or `-1` if there is
     /// no such region.
-    int matchingRegion(newRegion) {
-      int newOffset = newRegion.offset;
-      int newLength = newRegion.length;
+    int matchingRegion(NavigationRegion newRegion) {
+      var newOffset = newRegion.offset;
+      var newLength = newRegion.length;
       for (var i = 0; i < mergedRegions.length; i++) {
         var mergedRegion = mergedRegions[i];
         if (newOffset == mergedRegion.offset &&
diff --git a/pkg/analysis_server/lib/src/search/search_domain.dart b/pkg/analysis_server/lib/src/search/search_domain.dart
index 04542a8..f854cc4 100644
--- a/pkg/analysis_server/lib/src/search/search_domain.dart
+++ b/pkg/analysis_server/lib/src/search/search_domain.dart
@@ -11,6 +11,7 @@
 import 'package:analysis_server/src/search/element_references.dart';
 import 'package:analysis_server/src/search/type_hierarchy.dart';
 import 'package:analysis_server/src/services/search/search_engine.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/src/dart/analysis/search.dart' as search;
 
@@ -228,7 +229,8 @@
   }
 
   @override
-  protocol.Response? handleRequest(protocol.Request request) {
+  protocol.Response? handleRequest(
+      protocol.Request request, CancellationToken cancellationToken) {
     try {
       var requestName = request.method;
       if (requestName == SEARCH_REQUEST_FIND_ELEMENT_REFERENCES) {
diff --git a/pkg/analysis_server/lib/src/server/dev_server.dart b/pkg/analysis_server/lib/src/server/dev_server.dart
index b11c418..d59e2fa 100644
--- a/pkg/analysis_server/lib/src/server/dev_server.dart
+++ b/pkg/analysis_server/lib/src/server/dev_server.dart
@@ -80,20 +80,21 @@
           continue;
         }
 
-        String severity = error['severity'].toLowerCase();
+        var severity = (error['severity'] as String).toLowerCase();
         if (severity == 'warning' && exitCode < 1) {
           exitCode = 1;
         } else if (severity == 'error' && exitCode < 2) {
           exitCode = 2;
         }
 
-        String message = error['message'];
+        var message = error['message'] as String;
         if (message.endsWith('.')) {
           message = message.substring(0, message.length - 1);
         }
-        String code = error['code'];
-        int line = error['location']['startLine'];
-        int column = error['location']['startColumn'];
+        var code = error['code'] as String;
+        var location = error['location'] as Map<Object?, Object?>;
+        var line = location['startLine'] as int;
+        var column = location['startColumn'] as int;
 
         print('  $severity • $bold$message$none at $filePath:$line:$column • '
             '($code)');
diff --git a/pkg/analysis_server/lib/src/server/driver.dart b/pkg/analysis_server/lib/src/server/driver.dart
index 5016f76..47504a4 100644
--- a/pkg/analysis_server/lib/src/server/driver.dart
+++ b/pkg/analysis_server/lib/src/server/driver.dart
@@ -145,10 +145,12 @@
 
     var analysisServerOptions = AnalysisServerOptions();
     analysisServerOptions.newAnalysisDriverLog =
-        results[ANALYSIS_DRIVER_LOG] ?? results[ANALYSIS_DRIVER_LOG_ALIAS];
-    analysisServerOptions.clientId = results[CLIENT_ID];
+        (results[ANALYSIS_DRIVER_LOG] ?? results[ANALYSIS_DRIVER_LOG_ALIAS])
+            as String?;
+    analysisServerOptions.clientId = results[CLIENT_ID] as String?;
     if (results.wasParsed(USE_LSP)) {
-      analysisServerOptions.useLanguageServerProtocol = results[USE_LSP];
+      analysisServerOptions.useLanguageServerProtocol =
+          results[USE_LSP] as bool;
     } else {
       analysisServerOptions.useLanguageServerProtocol =
           results[SERVER_PROTOCOL] == PROTOCOL_LSP;
@@ -160,18 +162,18 @@
             ? 'unknown.client.lsp'
             : 'unknown.client.classic';
 
-    analysisServerOptions.clientVersion = results[CLIENT_VERSION];
-    analysisServerOptions.cacheFolder = results[CACHE_FOLDER];
-    analysisServerOptions.packagesFile = results[PACKAGES_FILE];
+    analysisServerOptions.clientVersion = results[CLIENT_VERSION] as String?;
+    analysisServerOptions.cacheFolder = results[CACHE_FOLDER] as String?;
+    analysisServerOptions.packagesFile = results[PACKAGES_FILE] as String?;
     analysisServerOptions.reportProtocolVersion =
-        results[REPORT_PROTOCOL_VERSION];
+        results[REPORT_PROTOCOL_VERSION] as String?;
 
     // Read in any per-SDK overrides specified in <sdk>/config/settings.json.
     var sdkConfig = SdkConfiguration.readFromSdk();
     analysisServerOptions.configurationOverrides = sdkConfig;
 
     // Analytics
-    bool disableAnalyticsForSession = results[SUPPRESS_ANALYTICS_FLAG];
+    var disableAnalyticsForSession = results[SUPPRESS_ANALYTICS_FLAG] as bool;
     if (results.wasParsed(TRAIN_USING)) {
       disableAnalyticsForSession = true;
     }
@@ -212,15 +214,16 @@
 
     if (telemetry.showAnalyticsUI) {
       if (results.wasParsed(ANALYTICS_FLAG)) {
-        analytics.enabled = results[ANALYTICS_FLAG];
+        analytics.enabled = results[ANALYTICS_FLAG] as bool;
         print(telemetry.createAnalyticsStatusMessage(analytics.enabled));
         return null;
       }
     }
 
     {
-      bool disableCompletion = results[DISABLE_SERVER_FEATURE_COMPLETION];
-      bool disableSearch = results[DISABLE_SERVER_FEATURE_SEARCH];
+      var disableCompletion =
+          results[DISABLE_SERVER_FEATURE_COMPLETION] as bool;
+      var disableSearch = results[DISABLE_SERVER_FEATURE_SEARCH] as bool;
       if (disableCompletion || disableSearch) {
         analysisServerOptions.featureSet = FeatureSet(
           completion: !disableCompletion,
@@ -229,7 +232,7 @@
       }
     }
 
-    if (results[HELP_OPTION]) {
+    if (results[HELP_OPTION] as bool) {
       _printUsage(parser, analytics, fromHelp: true);
       return null;
     }
@@ -244,8 +247,8 @@
     //
     // Initialize the instrumentation service.
     //
-    var logFilePath =
-        results[PROTOCOL_TRAFFIC_LOG] ?? results[PROTOCOL_TRAFFIC_LOG_ALIAS];
+    var logFilePath = (results[PROTOCOL_TRAFFIC_LOG] ??
+        results[PROTOCOL_TRAFFIC_LOG_ALIAS]) as String?;
     var allInstrumentationServices = this.instrumentationService == null
         ? <InstrumentationService>[]
         : [this.instrumentationService!];
@@ -274,8 +277,8 @@
     AnalysisEngine.instance.instrumentationService = instrumentationService;
 
     int? diagnosticServerPort;
-    final String? portValue =
-        results[DIAGNOSTIC_PORT] ?? results[DIAGNOSTIC_PORT_ALIAS];
+    final portValue =
+        (results[DIAGNOSTIC_PORT] ?? results[DIAGNOSTIC_PORT_ALIAS]) as String?;
     if (portValue != null) {
       try {
         diagnosticServerPort = int.parse(portValue);
@@ -324,10 +327,10 @@
     ErrorNotifier errorNotifier,
     SendPort? sendPort,
   ) {
-    var capture = results[DISABLE_SERVER_EXCEPTION_HANDLING]
+    var capture = results[DISABLE_SERVER_EXCEPTION_HANDLING] as bool
         ? (_, Function f, {Function(String)? print}) => f()
         : _captureExceptions;
-    var trainDirectory = results[TRAIN_USING];
+    var trainDirectory = results[TRAIN_USING] as String?;
     if (trainDirectory != null) {
       if (!FileSystemEntity.isDirectorySync(trainDirectory)) {
         print("Training directory '$trainDirectory' not found.\n");
@@ -426,7 +429,7 @@
           if (sendPort == null) exit(0);
         });
       },
-          print: results[INTERNAL_PRINT_TO_CONSOLE]
+          print: results[INTERNAL_PRINT_TO_CONSOLE] as bool
               ? null
               : httpServer!.recordPrint);
     }
@@ -440,7 +443,7 @@
     int? diagnosticServerPort,
     ErrorNotifier errorNotifier,
   ) {
-    var capture = args[DISABLE_SERVER_EXCEPTION_HANDLING]
+    var capture = args[DISABLE_SERVER_EXCEPTION_HANDLING] as bool
         ? (_, Function f, {Function(String)? print}) => f()
         : _captureExceptions;
 
@@ -483,7 +486,7 @@
       InstrumentationService service, void Function() callback,
       {void Function(String line)? print}) {
     void errorFunction(Zone self, ZoneDelegate parent, Zone zone,
-        dynamic exception, StackTrace stackTrace) {
+        Object exception, StackTrace stackTrace) {
       service.logException(exception, stackTrace);
       throw exception;
     }
diff --git a/pkg/analysis_server/lib/src/server/sdk_configuration.dart b/pkg/analysis_server/lib/src/server/sdk_configuration.dart
index 39eb0d1..23d6a76 100644
--- a/pkg/analysis_server/lib/src/server/sdk_configuration.dart
+++ b/pkg/analysis_server/lib/src/server/sdk_configuration.dart
@@ -40,19 +40,21 @@
   }
 
   /// Whether analytics is forced on.
-  bool? get analyticsForceEnabled => _values['server.analytics.forceEnabled'];
+  bool? get analyticsForceEnabled =>
+      _values['server.analytics.forceEnabled'] as bool?;
 
   /// Return an override value for the analysis server's google analytics ID, or
   /// `null` if the default value should be used.
-  String? get analyticsId => _values['server.analytics.id'];
+  String? get analyticsId => _values['server.analytics.id'] as String?;
 
   /// Whether crash reporting is forced on.
   bool? get crashReportingForceEnabled =>
-      _values['server.crash.reporting.forceEnabled'];
+      _values['server.crash.reporting.forceEnabled'] as bool?;
 
   /// Return an override value for the analysis server's crash reporting product
   /// ID, or `null` if the default value should be used.
-  String? get crashReportingId => _values['server.crash.reporting.id'];
+  String? get crashReportingId =>
+      _values['server.crash.reporting.id'] as String?;
 
   /// Return a string describing the contents of this SDK configuration.
   String get displayString {
@@ -67,9 +69,10 @@
 
   void _readFromFile(File file) {
     try {
-      Map m = jsonDecode(file.readAsStringSync());
-      for (var key in m.keys) {
-        _values[key] = m[key];
+      var content =
+          jsonDecode(file.readAsStringSync()) as Map<Object?, Object?>;
+      for (var key in content.keys) {
+        _values[key as String] = content[key];
       }
     } catch (_) {
       // ignore issues reading the file
diff --git a/pkg/analysis_server/lib/src/services/completion/dart/arglist_contributor.dart b/pkg/analysis_server/lib/src/services/completion/dart/arglist_contributor.dart
index a6ff620..8cdcb87 100644
--- a/pkg/analysis_server/lib/src/services/completion/dart/arglist_contributor.dart
+++ b/pkg/analysis_server/lib/src/services/completion/dart/arglist_contributor.dart
@@ -7,10 +7,9 @@
 import 'package:analysis_server/src/services/completion/dart/completion_manager.dart';
 import 'package:analysis_server/src/services/completion/dart/suggestion_builder.dart';
 import 'package:analysis_server/src/utilities/flutter.dart';
+import 'package:analyzer/dart/analysis/features.dart';
 import 'package:analyzer/dart/ast/ast.dart';
-import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element.dart';
-import 'package:analyzer/dart/element/type.dart';
 
 /// A contributor that produces suggestions for named expression labels that
 /// correspond to named parameters when completing in argument lists.
@@ -100,7 +99,9 @@
     if (_isEditingNamedArgLabel() ||
         _isAppendingToArgList() ||
         _isAddingLabelToPositional()) {
-      if (requiredCount == 0 || requiredCount < _argCount()) {
+      if (request.featureSet.isEnabled(Feature.named_arguments_anywhere) ||
+          requiredCount == 0 ||
+          requiredCount < _argCount()) {
         // If there's a replacement range that starts at the caret, it will be
         // for an identifier that is not the named label and therefore it should
         // not be replaced.
@@ -110,7 +111,8 @@
                 ? 0
                 : null;
 
-        var addTrailingComma = !_isFollowedByAComma() && _isInFlutterCreation();
+        var addTrailingComma =
+            !request.target.isFollowedByComma && _isInFlutterCreation();
         _addDefaultParamSuggestions(parameters,
             appendComma: addTrailingComma,
             replacementLength: replacementLength);
@@ -119,12 +121,7 @@
       _addDefaultParamSuggestions(parameters, appendComma: true);
     } else if (_isInsertingToArgListWithSynthetic()) {
       _addDefaultParamSuggestions(parameters,
-          appendComma: !_isFollowedByAComma());
-    } else {
-      var argument = request.target.containingNode;
-      if (argument is NamedExpression) {
-        _buildClosureSuggestions(argument);
-      }
+          appendComma: !request.target.isFollowedByComma);
     }
   }
 
@@ -144,15 +141,6 @@
     return 0;
   }
 
-  void _buildClosureSuggestions(NamedExpression argument) {
-    var type = argument.staticParameterElement?.type;
-    if (type is FunctionType) {
-      builder.suggestClosure(type,
-          includeTrailingComma:
-              argument.endToken.next?.type != TokenType.COMMA);
-    }
-  }
-
   /// Return `true` if the caret is preceding an arg where a name could be added
   /// (turning a positional arg into a named arg).
   bool _isAddingLabelToPositional() {
@@ -219,24 +207,6 @@
     return false;
   }
 
-  bool _isFollowedByAComma() {
-    // new A(^); NO
-    // new A(one: 1, ^); NO
-    // new A(^ , one: 1); YES
-    // new A(^), ... NO
-
-    var containingNode = request.target.containingNode;
-    var entity = request.target.entity;
-    var token = entity is AstNode
-        ? entity.endToken
-        : entity is Token
-            ? entity
-            : null;
-    return (token != containingNode.endToken) &&
-        token?.next?.type == TokenType.COMMA &&
-        !(token?.next?.isSynthetic ?? false);
-  }
-
   bool _isInFlutterCreation() {
     var flutter = Flutter.instance;
     var containingNode = request.target.containingNode;
diff --git a/pkg/analysis_server/lib/src/services/completion/dart/closure_contributor.dart b/pkg/analysis_server/lib/src/services/completion/dart/closure_contributor.dart
new file mode 100644
index 0000000..5700872
--- /dev/null
+++ b/pkg/analysis_server/lib/src/services/completion/dart/closure_contributor.dart
@@ -0,0 +1,33 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analysis_server/src/provisional/completion/dart/completion_dart.dart';
+import 'package:analysis_server/src/services/completion/dart/completion_manager.dart';
+import 'package:analysis_server/src/services/completion/dart/suggestion_builder.dart';
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/element/type.dart';
+
+/// A contributor that produces a closure matching the context type.
+class ClosureContributor extends DartCompletionContributor {
+  ClosureContributor(
+    DartCompletionRequest request,
+    SuggestionBuilder builder,
+  ) : super(request, builder);
+
+  bool get _isArgument {
+    var node = request.target.containingNode;
+    return node is ArgumentList || node is NamedExpression;
+  }
+
+  @override
+  Future<void> computeSuggestions() async {
+    var contextType = request.contextType;
+    if (contextType is FunctionType) {
+      builder.suggestClosure(
+        contextType,
+        includeTrailingComma: _isArgument && !request.target.isFollowedByComma,
+      );
+    }
+  }
+}
diff --git a/pkg/analysis_server/lib/src/services/completion/dart/completion_manager.dart b/pkg/analysis_server/lib/src/services/completion/dart/completion_manager.dart
index 90da0ef..4193128 100644
--- a/pkg/analysis_server/lib/src/services/completion/dart/completion_manager.dart
+++ b/pkg/analysis_server/lib/src/services/completion/dart/completion_manager.dart
@@ -6,6 +6,7 @@
 import 'package:analysis_server/src/provisional/completion/completion_core.dart';
 import 'package:analysis_server/src/provisional/completion/dart/completion_dart.dart';
 import 'package:analysis_server/src/services/completion/dart/arglist_contributor.dart';
+import 'package:analysis_server/src/services/completion/dart/closure_contributor.dart';
 import 'package:analysis_server/src/services/completion/dart/combinator_contributor.dart';
 import 'package:analysis_server/src/services/completion/dart/documentation_cache.dart';
 import 'package:analysis_server/src/services/completion/dart/extension_member_contributor.dart';
@@ -138,6 +139,7 @@
     var builder = SuggestionBuilder(request, listener: listener);
     var contributors = <DartCompletionContributor>[
       ArgListContributor(request, builder),
+      ClosureContributor(request, builder),
       CombinatorContributor(request, builder),
       ExtensionMemberContributor(request, builder),
       FieldFormalContributor(request, builder),
diff --git a/pkg/analysis_server/lib/src/services/completion/dart/documentation_cache.dart b/pkg/analysis_server/lib/src/services/completion/dart/documentation_cache.dart
index 0ca62d6..8411094 100644
--- a/pkg/analysis_server/lib/src/services/completion/dart/documentation_cache.dart
+++ b/pkg/analysis_server/lib/src/services/completion/dart/documentation_cache.dart
@@ -162,17 +162,16 @@
 }
 
 extension on Map<String, DocumentationWithSummary> {
-  /// Cache the data associated with the top-level [element], and return the
-  /// [key] used for the element. This does not cache any data associated with
-  /// any other elements, including children of the [element].
-  String? cacheTopLevelElement(
-      DartdocDirectiveInfo dartdocDirectiveInfo, Element element) {
-    var key = element.name;
-    if (key == null) {
-      return null;
+  /// Cache the data associated with the [element], using the given [key].
+  DocumentationWithSummary? cacheElement(
+      DartdocDirectiveInfo dartdocDirectiveInfo, String key, Element element) {
+    var documentation = DartUnitHoverComputer.computeDocumentation(
+        dartdocDirectiveInfo, element,
+        includeSummary: true);
+    if (documentation is DocumentationWithSummary) {
+      return this[key] = documentation;
     }
-    cacheElement(dartdocDirectiveInfo, key, element);
-    return key;
+    return this[key] = DocumentationCache._emptyDocs;
   }
 
   /// Cache the data associated with the [member] element given that the key
@@ -186,15 +185,16 @@
     cacheElement(dartdocDirectiveInfo, '$parentKey.$name', member);
   }
 
-  /// Cache the data associated with the [element], using the given [key].
-  DocumentationWithSummary? cacheElement(
-      DartdocDirectiveInfo dartdocDirectiveInfo, String key, Element element) {
-    var documentation = DartUnitHoverComputer.computeDocumentation(
-        dartdocDirectiveInfo, element,
-        includeSummary: true);
-    if (documentation is DocumentationWithSummary) {
-      return this[key] = documentation;
+  /// Cache the data associated with the top-level [element], and return the
+  /// [key] used for the element. This does not cache any data associated with
+  /// any other elements, including children of the [element].
+  String? cacheTopLevelElement(
+      DartdocDirectiveInfo dartdocDirectiveInfo, Element element) {
+    var key = element.name;
+    if (key == null) {
+      return null;
     }
-    return this[key] = DocumentationCache._emptyDocs;
+    cacheElement(dartdocDirectiveInfo, key, element);
+    return key;
   }
 }
diff --git a/pkg/analysis_server/lib/src/services/completion/dart/extension_cache.dart b/pkg/analysis_server/lib/src/services/completion/dart/extension_cache.dart
deleted file mode 100644
index 38481dc..0000000
--- a/pkg/analysis_server/lib/src/services/completion/dart/extension_cache.dart
+++ /dev/null
@@ -1,105 +0,0 @@
-// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-import 'package:analyzer/dart/analysis/results.dart';
-import 'package:analyzer/dart/ast/ast.dart';
-import 'package:analyzer/dart/element/element.dart';
-
-/// Cached data about the extensions defined in a single analysis context.
-class ExtensionCache {
-  /// A set containing the paths of the compilation units that have been cached.
-  /// The set is used to prevent caching the same data multiple times.
-  final Set<String> processedUnits = {};
-
-  /// A map from the name of a non-static public extension member to the set of
-  /// paths to libraries defining an extension member with that name.
-  final Map<String, Set<UnitInLibrary>> membersByName = {};
-
-  /// Initialize a newly created cache.
-  ExtensionCache();
-
-  /// Fill the cache with data from the [result].
-  void cacheFromResult(ResolvedUnitResult result) {
-    var element = result.unit.declaredElement;
-    if (element != null) {
-      _cacheFromElement(element);
-      for (var library in result.libraryElement.importedLibraries) {
-        _cacheLibrary(library);
-      }
-    }
-  }
-
-  /// Fill the cache with data from the [compilationUnit].
-  void _cacheFromElement(CompilationUnitElement compilationUnit) {
-    // Record that we've cached data for the compilation unit.
-    var unitPath = _keyForUnit(compilationUnit);
-    processedUnits.add(unitPath);
-
-    // Flush any data that was previously cached for the compilation unit.
-    for (var set in membersByName.values) {
-      set.removeWhere((element) => element.unitPath == unitPath);
-    }
-
-    // Cache the data for the compilation unit.
-    var libraryPath = compilationUnit.librarySource.fullName;
-    for (var extension in compilationUnit.extensions) {
-      var extensionName = extension.name;
-      if (extensionName != null && !Identifier.isPrivateName(extensionName)) {
-        for (var member in extension.accessors) {
-          if (!member.isSynthetic) {
-            _recordMember(unitPath, libraryPath, member.displayName);
-          }
-        }
-        for (var member in extension.fields) {
-          if (!member.isSynthetic) {
-            _recordMember(unitPath, libraryPath, member.name);
-          }
-        }
-        for (var member in extension.methods) {
-          _recordMember(unitPath, libraryPath, member.name);
-        }
-      }
-    }
-  }
-
-  /// Cache the data for the given [library] and every library exported from it
-  /// if it hasn't already been cached.
-  void _cacheLibrary(LibraryElement library) {
-    if (_hasDataFor(library.definingCompilationUnit)) {
-      return;
-    }
-    for (var unit in library.units) {
-      _cacheFromElement(unit);
-    }
-    for (var exported in library.exportedLibraries) {
-      _cacheLibrary(exported);
-    }
-  }
-
-  /// Return `true` if the cache contains data for the [compilationUnit].
-  bool _hasDataFor(CompilationUnitElement compilationUnit) {
-    return processedUnits.contains(_keyForUnit(compilationUnit));
-  }
-
-  /// Return the key used in the [extensionCache] for the [compilationUnit].
-  String _keyForUnit(CompilationUnitElement compilationUnit) =>
-      compilationUnit.source.fullName;
-
-  /// Record that an extension member with the given [name] is defined in the
-  /// compilation unit with the [unitPath] in the library with the
-  /// [libraryPath].
-  void _recordMember(String unitPath, String libraryPath, String name) {
-    membersByName
-        .putIfAbsent(name, () => {})
-        .add(UnitInLibrary(unitPath, libraryPath));
-  }
-}
-
-/// A representation of a compilation unit in a library.
-class UnitInLibrary {
-  final String unitPath;
-  final String libraryPath;
-
-  UnitInLibrary(this.unitPath, this.libraryPath);
-}
diff --git a/pkg/analysis_server/lib/src/services/completion/dart/extension_member_contributor.dart b/pkg/analysis_server/lib/src/services/completion/dart/extension_member_contributor.dart
index aa75988..3b4f5f2 100644
--- a/pkg/analysis_server/lib/src/services/completion/dart/extension_member_contributor.dart
+++ b/pkg/analysis_server/lib/src/services/completion/dart/extension_member_contributor.dart
@@ -7,10 +7,10 @@
 import 'package:analysis_server/src/provisional/completion/dart/completion_dart.dart';
 import 'package:analysis_server/src/services/completion/dart/completion_manager.dart';
 import 'package:analysis_server/src/services/completion/dart/suggestion_builder.dart';
-import 'package:analysis_server/src/utilities/extensions/element.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
+import 'package:analyzer/src/dart/resolver/applicable_extensions.dart';
 
 /// A contributor that produces suggestions based on the members of an
 /// extension.
@@ -115,21 +115,21 @@
 
   void _addExtensionMembers(List<ExtensionElement> extensions,
       CompletionSuggestionKind? kind, DartType type) {
-    var containingLibrary = request.libraryElement;
-    var typeSystem = containingLibrary.typeSystem;
-    for (var extension in extensions) {
-      var extendedType =
-          extension.resolvedExtendedType(containingLibrary, type);
-      if (extendedType != null && typeSystem.isSubtypeOf(type, extendedType)) {
-        var inheritanceDistance = 0.0;
-        if (type is InterfaceType && extendedType is InterfaceType) {
-          inheritanceDistance = memberBuilder.request.featureComputer
-              .inheritanceDistanceFeature(type.element, extendedType.element);
-        }
-        // TODO(brianwilkerson) We might want to apply the substitution to the
-        //  members of the extension for display purposes.
-        _addInstanceMembers(extension, kind, inheritanceDistance);
+    var applicableExtensions = extensions.applicableTo(
+      targetLibrary: request.libraryElement,
+      targetType: type,
+    );
+    for (var instantiatedExtension in applicableExtensions) {
+      var extendedType = instantiatedExtension.extendedType;
+      var inheritanceDistance = 0.0;
+      if (type is InterfaceType && extendedType is InterfaceType) {
+        inheritanceDistance = memberBuilder.request.featureComputer
+            .inheritanceDistanceFeature(type.element, extendedType.element);
       }
+      // TODO(brianwilkerson) We might want to apply the substitution to the
+      //  members of the extension for display purposes.
+      _addInstanceMembers(
+          instantiatedExtension.extension, kind, inheritanceDistance);
     }
   }
 
diff --git a/pkg/analysis_server/lib/src/services/completion/dart/not_imported_contributor.dart b/pkg/analysis_server/lib/src/services/completion/dart/not_imported_contributor.dart
index 53550d8..070294f 100644
--- a/pkg/analysis_server/lib/src/services/completion/dart/not_imported_contributor.dart
+++ b/pkg/analysis_server/lib/src/services/completion/dart/not_imported_contributor.dart
@@ -11,10 +11,7 @@
 import 'package:analysis_server/src/services/completion/dart/local_library_contributor.dart';
 import 'package:analysis_server/src/services/completion/dart/suggestion_builder.dart';
 import 'package:analyzer/dart/element/element.dart';
-import 'package:analyzer/src/dart/analysis/file_state.dart';
-import 'package:analyzer/src/lint/pub.dart';
-import 'package:analyzer/src/workspace/pub.dart';
-import 'package:collection/collection.dart';
+import 'package:analyzer/src/dart/analysis/file_state_filter.dart';
 
 /// A contributor of suggestions from not yet imported libraries.
 class NotImportedContributor extends DartCompletionContributor {
@@ -33,7 +30,9 @@
     var analysisDriver = request.analysisContext.driver;
 
     var fsState = analysisDriver.fsState;
-    var filter = _buildFilter(fsState);
+    var filter = FileStateFilter(
+      fsState.getFileForPath(request.path),
+    );
 
     try {
       await analysisDriver.discoverAvailableFiles().timeout(budget.left);
@@ -80,16 +79,6 @@
     builder.suggestionAdded = null;
   }
 
-  _Filter _buildFilter(FileSystemState fsState) {
-    var file = fsState.getFileForPath(request.path);
-    var workspacePackage = file.workspacePackage;
-    if (workspacePackage is PubWorkspacePackage) {
-      return _PubFilter(workspacePackage, file.path);
-    } else {
-      return _AnyFilter();
-    }
-  }
-
   void _buildSuggestions(List<Element> elements) {
     var visitor = LibraryElementSuggestionBuilder(request, builder);
     for (var element in elements) {
@@ -97,96 +86,3 @@
     }
   }
 }
-
-class _AnyFilter implements _Filter {
-  @override
-  bool shouldInclude(FileState file) => true;
-}
-
-abstract class _Filter {
-  bool shouldInclude(FileState file);
-}
-
-class _PubFilter implements _Filter {
-  final PubWorkspacePackage targetPackage;
-  final String? targetPackageName;
-  final bool targetInLib;
-  final Set<String> dependencies;
-
-  factory _PubFilter(PubWorkspacePackage package, String path) {
-    var inLib = package.workspace.provider
-        .getFolder(package.root)
-        .getChildAssumingFolder('lib')
-        .contains(path);
-
-    var dependencies = <String>{};
-    var pubspec = package.pubspec;
-    if (pubspec != null) {
-      dependencies.addAll(pubspec.dependencies.names);
-      if (!inLib) {
-        dependencies.addAll(pubspec.devDependencies.names);
-      }
-    }
-
-    return _PubFilter._(
-      targetPackage: package,
-      targetPackageName: pubspec?.name?.value.text,
-      targetInLib: inLib,
-      dependencies: dependencies,
-    );
-  }
-
-  _PubFilter._({
-    required this.targetPackage,
-    required this.targetPackageName,
-    required this.targetInLib,
-    required this.dependencies,
-  });
-
-  @override
-  bool shouldInclude(FileState file) {
-    var uri = file.uriProperties;
-    if (uri.isDart) {
-      return true;
-    }
-
-    // Normally only package URIs are available.
-    // But outside of lib/ we allow any files of this package.
-    var packageName = uri.packageName;
-    if (packageName == null) {
-      if (targetInLib) {
-        return false;
-      } else {
-        var filePackage = file.workspacePackage;
-        return filePackage is PubWorkspacePackage &&
-            filePackage.root == targetPackage.root;
-      }
-    }
-
-    // Any `package:` library from the same package.
-    if (packageName == targetPackageName) {
-      return true;
-    }
-
-    // If not the same package, must be public.
-    if (uri.isSrc) {
-      return false;
-    }
-
-    return dependencies.contains(packageName);
-  }
-}
-
-extension on PSDependencyList? {
-  List<String> get names {
-    final self = this;
-    if (self == null) {
-      return const [];
-    } else {
-      return self
-          .map((dependency) => dependency.name?.text)
-          .whereNotNull()
-          .toList();
-    }
-  }
-}
diff --git a/pkg/analysis_server/lib/src/services/completion/dart/suggestion_builder.dart b/pkg/analysis_server/lib/src/services/completion/dart/suggestion_builder.dart
index 8ffc7d4..0e7d181 100644
--- a/pkg/analysis_server/lib/src/services/completion/dart/suggestion_builder.dart
+++ b/pkg/analysis_server/lib/src/services/completion/dart/suggestion_builder.dart
@@ -547,8 +547,7 @@
       var suggestion = CompletionSuggestion(CompletionSuggestionKind.IDENTIFIER,
           Relevance.label, completion, completion.length, 0, false, false);
       suggestion.element = createLocalElement(
-          request.source, protocol.ElementKind.LABEL, label.label,
-          returnType: NO_RETURN_TYPE);
+          request.source, protocol.ElementKind.LABEL, label.label);
       _add(suggestion);
     }
   }
diff --git a/pkg/analysis_server/lib/src/services/completion/dart/utilities.dart b/pkg/analysis_server/lib/src/services/completion/dart/utilities.dart
index 33d20fe..eef975c 100644
--- a/pkg/analysis_server/lib/src/services/completion/dart/utilities.dart
+++ b/pkg/analysis_server/lib/src/services/completion/dart/utilities.dart
@@ -7,11 +7,8 @@
     show CompletionSuggestion, Location;
 import 'package:analysis_server/src/services/completion/dart/completion_manager.dart';
 import 'package:analyzer/dart/ast/ast.dart';
-import 'package:analyzer/dart/ast/standard_ast_factory.dart';
-import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
-import 'package:analyzer/src/dart/ast/token.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer_plugin/protocol/protocol_common.dart' as protocol
     show Element, ElementKind;
@@ -28,13 +25,6 @@
   return b.relevance.compareTo(a.relevance);
 };
 
-/// A marker used in place of `null` when a function has no return type.
-final NamedType NO_RETURN_TYPE = astFactory.namedType(
-  name: astFactory.simpleIdentifier(
-    StringToken(TokenType.IDENTIFIER, '', 0),
-  ),
-);
-
 /// Add default argument list text and ranges based on the given
 /// [requiredParams] and [namedParams].
 void addDefaultArgDetails(
diff --git a/pkg/analysis_server/lib/src/services/completion/statement/statement_completion.dart b/pkg/analysis_server/lib/src/services/completion/statement/statement_completion.dart
index e337213..2da4819 100644
--- a/pkg/analysis_server/lib/src/services/completion/statement/statement_completion.dart
+++ b/pkg/analysis_server/lib/src/services/completion/statement/statement_completion.dart
@@ -262,7 +262,7 @@
   void _checkExpressions(AstNode node) {
     // Note: This may queue edits that have to be accounted for later.
     // See _lengthOfInsertions().
-    AstNode? errorMatching(errorCode, {partialMatch}) {
+    AstNode? errorMatching(ErrorCode errorCode, {Pattern? partialMatch}) {
       var error = _findError(errorCode, partialMatch: partialMatch);
       if (error == null) {
         return null;
@@ -1069,7 +1069,7 @@
         node, stmt, DartStatementCompletion.COMPLETE_WHILE_STMT);
   }
 
-  engine.AnalysisError? _findError(ErrorCode code, {partialMatch}) {
+  engine.AnalysisError? _findError(ErrorCode code, {Pattern? partialMatch}) {
     return errors.firstWhereOrNull((err) =>
         err.errorCode == code &&
         (partialMatch == null ? true : err.message.contains(partialMatch)));
@@ -1169,7 +1169,7 @@
     return Position(file, offset);
   }
 
-  void _removeError(errorCode, {partialMatch}) {
+  void _removeError(ErrorCode errorCode, {Pattern? partialMatch}) {
     var error = _findError(errorCode, partialMatch: partialMatch);
     if (error != null) {
       errors.remove(error);
diff --git a/pkg/analysis_server/lib/src/services/completion/yaml/analysis_options_generator.dart b/pkg/analysis_server/lib/src/services/completion/yaml/analysis_options_generator.dart
index bd175b9..18f1072 100644
--- a/pkg/analysis_server/lib/src/services/completion/yaml/analysis_options_generator.dart
+++ b/pkg/analysis_server/lib/src/services/completion/yaml/analysis_options_generator.dart
@@ -23,6 +23,7 @@
       AnalyzerOptions.errors: EmptyProducer(),
       AnalyzerOptions.exclude: EmptyProducer(),
       AnalyzerOptions.language: MapProducer({
+        AnalyzerOptions.strictCasts: EmptyProducer(),
         AnalyzerOptions.strictInference: EmptyProducer(),
         AnalyzerOptions.strictRawTypes: EmptyProducer(),
       }),
diff --git a/pkg/analysis_server/lib/src/services/completion/yaml/yaml_completion_generator.dart b/pkg/analysis_server/lib/src/services/completion/yaml/yaml_completion_generator.dart
index 618ba40..53c3de6 100644
--- a/pkg/analysis_server/lib/src/services/completion/yaml/yaml_completion_generator.dart
+++ b/pkg/analysis_server/lib/src/services/completion/yaml/yaml_completion_generator.dart
@@ -131,7 +131,7 @@
         // value that was next in the path.
         var key = node.keyAtValue(path[i + 1]);
         if (key is YamlScalar) {
-          producer = producer.producerForKey(key.value);
+          producer = producer.producerForKey(key.value as String);
           // Otherwise, if the item next in the path was a key itself, use the
           // current producer to provide completion for the key.
         } else if (node.nodes.containsKey(path[i + 1])) {
@@ -154,10 +154,11 @@
     List<String> siblingsInList(YamlList list, YamlNode? currentElement) {
       var siblings = <String>[];
       for (var element in list.nodes) {
-        if (element != currentElement &&
-            element is YamlScalar &&
-            element.value is String) {
-          siblings.add(element.value);
+        if (element != currentElement && element is YamlScalar) {
+          var value = element.value;
+          if (value is String) {
+            siblings.add(value);
+          }
         }
       }
       return siblings;
diff --git a/pkg/analysis_server/lib/src/services/correction/assist_internal.dart b/pkg/analysis_server/lib/src/services/correction/assist_internal.dart
index c2e4e39..2e8d400 100644
--- a/pkg/analysis_server/lib/src/services/correction/assist_internal.dart
+++ b/pkg/analysis_server/lib/src/services/correction/assist_internal.dart
@@ -221,7 +221,7 @@
     for (var multiGenerator in multiGenerators) {
       var multiProducer = multiGenerator();
       multiProducer.configure(context);
-      for (var producer in multiProducer.producers) {
+      await for (var producer in multiProducer.producers) {
         await compute(producer);
       }
     }
diff --git a/pkg/analysis_server/lib/src/services/correction/bulk_fix_processor.dart b/pkg/analysis_server/lib/src/services/correction/bulk_fix_processor.dart
index 0b6145c..5f286c8 100644
--- a/pkg/analysis_server/lib/src/services/correction/bulk_fix_processor.dart
+++ b/pkg/analysis_server/lib/src/services/correction/bulk_fix_processor.dart
@@ -220,7 +220,6 @@
           workspace,
           unit,
           error,
-          (name) => [],
         );
         await _fixSingleError(fixContext, unit, error, overrideSet);
       }
@@ -266,7 +265,6 @@
         workspace,
         result,
         diagnostic,
-        (name) => [],
       );
     }
 
@@ -383,7 +381,7 @@
           for (var multiGenerator in multiGenerators) {
             var multiProducer = multiGenerator();
             multiProducer.configure(context);
-            for (var producer in multiProducer.producers) {
+            await for (var producer in multiProducer.producers) {
               await _generateFix(context, producer, codeName);
             }
           }
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/abstract_producer.dart b/pkg/analysis_server/lib/src/services/correction/dart/abstract_producer.dart
index 56442ae..79f8ef3 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/abstract_producer.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/abstract_producer.dart
@@ -6,8 +6,6 @@
 
 import 'package:_fe_analyzer_shared/src/scanner/token.dart';
 import 'package:analysis_server/plugin/edit/fix/fix_dart.dart';
-import 'package:analysis_server/src/services/completion/dart/extension_cache.dart';
-import 'package:analysis_server/src/services/correction/fix/dart/top_level_declarations.dart';
 import 'package:analysis_server/src/services/correction/fix/data_driven/transform_override_set.dart';
 import 'package:analysis_server/src/services/correction/util.dart';
 import 'package:analysis_server/src/utilities/flutter.dart';
@@ -302,7 +300,7 @@
 /// assists).
 abstract class MultiCorrectionProducer extends _AbstractCorrectionProducer {
   /// Return each of the individual producers generated by this producer.
-  Iterable<CorrectionProducer> get producers;
+  Stream<CorrectionProducer> get producers;
 }
 
 /// An object that can compute a correction (fix or assist) in a Dart file.
@@ -413,9 +411,6 @@
   /// Returns the EOL to use for this [CompilationUnit].
   String get eol => utils.endOfLine;
 
-  /// Return the extension cache used to find available extensions.
-  ExtensionCache get extensionCache => _context.dartFixContext!.extensionCache;
-
   String get file => _context.file;
 
   Flutter get flutter => Flutter.instance;
@@ -491,10 +486,15 @@
     return utils.getRangeText(range);
   }
 
-  /// Return the top-level declarations with the [name] in libraries that are
-  /// available to this context.
-  List<TopLevelDeclaration> getTopLevelDeclarations(String name) =>
-      _context.dartFixContext!.getTopLevelDeclarations(name);
+  /// Return the mapping from a library (that is available to this context) to
+  /// a top-level declaration that is exported (not necessary declared) by this
+  /// library, and has the requested base name. For getters and setters the
+  /// corresponding top-level variable is returned.
+  Future<Map<LibraryElement, Element>> getTopLevelDeclarations(
+    String baseName,
+  ) {
+    return _context.dartFixContext!.getTopLevelDeclarations(baseName);
+  }
 
   /// Return `true` the lint with the given [name] is enabled.
   bool isLintEnabled(String name) {
@@ -523,6 +523,12 @@
     return false;
   }
 
+  /// Return libraries with extensions that declare non-static public
+  /// extension members with the [memberName].
+  Stream<LibraryElement> librariesWithExtensions(String memberName) {
+    return _context.dartFixContext!.librariesWithExtensions(memberName);
+  }
+
   /// Return `true` if the given [node] is in a location where an implicit
   /// constructor invocation would be allowed.
   bool mightBeImplicitConstructor(AstNode node) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/add_missing_parameter.dart b/pkg/analysis_server/lib/src/services/correction/dart/add_missing_parameter.dart
index 1f11731..04adf5d 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/add_missing_parameter.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/add_missing_parameter.dart
@@ -11,7 +11,7 @@
 
 class AddMissingParameter extends MultiCorrectionProducer {
   @override
-  Iterable<CorrectionProducer> get producers sync* {
+  Stream<CorrectionProducer> get producers async* {
     // node is the unmatched argument.
     var argumentList = node.parent;
     if (argumentList is! ArgumentList) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/add_return_null.dart b/pkg/analysis_server/lib/src/services/correction/dart/add_return_null.dart
new file mode 100644
index 0000000..8b37810
--- /dev/null
+++ b/pkg/analysis_server/lib/src/services/correction/dart/add_return_null.dart
@@ -0,0 +1,76 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analysis_server/src/services/correction/dart/abstract_producer.dart';
+import 'package:analysis_server/src/services/correction/fix.dart';
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer_plugin/utilities/change_builder/change_builder_core.dart';
+import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
+
+class AddReturnNull extends CorrectionProducer {
+  @override
+  bool get canBeAppliedInBulk => true;
+
+  @override
+  bool get canBeAppliedToFile => true;
+
+  @override
+  FixKind get fixKind => DartFixKind.ADD_RETURN_NULL;
+
+  @override
+  FixKind? get multiFixKind => DartFixKind.ADD_RETURN_NULL_MULTI;
+
+  @override
+  Future<void> compute(ChangeBuilder builder) async {
+    Block block;
+
+    var coveringNode = coveredNode;
+    if (coveringNode is Block) {
+      block = coveringNode;
+    } else if (coveringNode is SimpleIdentifier) {
+      var declaration = coveringNode.parent;
+      if (declaration is FunctionDeclaration) {
+        var body = declaration.functionExpression.body;
+        if (body is BlockFunctionBody) {
+          block = body.block;
+        } else {
+          return;
+        }
+      } else if (declaration is MethodDeclaration) {
+        var body = declaration.body;
+        if (body is BlockFunctionBody) {
+          block = body.block;
+        } else {
+          return;
+        }
+      } else {
+        return;
+      }
+    } else {
+      return;
+    }
+    int position;
+    String returnStatement;
+    if (block.statements.isEmpty) {
+      position = block.offset + 1;
+      var prefix = utils.getLinePrefix(block.offset);
+      returnStatement =
+          '$eol$prefix${utils.getIndent(1)}return null;$eol$prefix';
+    } else {
+      var lastStatement = block.statements.last;
+      position = lastStatement.offset + lastStatement.length;
+      var prefix = utils.getNodePrefix(lastStatement);
+      returnStatement = '$eol${prefix}return null;';
+    }
+
+    await builder.addDartFileEdit(file, (builder) {
+      builder.addInsertion(position, (builder) {
+        builder.write(returnStatement);
+      });
+    });
+  }
+
+  /// Return an instance of this class. Used as a tear-off in `FixProcessor`.
+  static AddReturnNull newInstance() => AddReturnNull();
+}
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/add_super_constructor_invocation.dart b/pkg/analysis_server/lib/src/services/correction/dart/add_super_constructor_invocation.dart
index fa1537b..86f5968 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/add_super_constructor_invocation.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/add_super_constructor_invocation.dart
@@ -13,7 +13,7 @@
 
 class AddSuperConstructorInvocation extends MultiCorrectionProducer {
   @override
-  Iterable<CorrectionProducer> get producers sync* {
+  Stream<CorrectionProducer> get producers async* {
     var targetConstructor = node.parent;
     if (targetConstructor is! ConstructorDeclaration) {
       return;
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/change_argument_name.dart b/pkg/analysis_server/lib/src/services/correction/dart/change_argument_name.dart
index 0442afb..54c57a4 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/change_argument_name.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/change_argument_name.dart
@@ -17,7 +17,7 @@
   static const _maxDistance = 4;
 
   @override
-  Iterable<CorrectionProducer> get producers sync* {
+  Stream<CorrectionProducer> get producers async* {
     var namedContext = _getNamedParameterNames();
     if (namedContext == null) {
       return;
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/convert_to_field_parameter.dart b/pkg/analysis_server/lib/src/services/correction/dart/convert_to_field_parameter.dart
index 447adee..fde8eca 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/convert_to_field_parameter.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/convert_to_field_parameter.dart
@@ -126,6 +126,8 @@
         }
       }
     }
+
+    return null;
   }
 }
 
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/create_constructor_super.dart b/pkg/analysis_server/lib/src/services/correction/dart/create_constructor_super.dart
index a40ed18..c571123 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/create_constructor_super.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/create_constructor_super.dart
@@ -12,7 +12,7 @@
 
 class CreateConstructorSuper extends MultiCorrectionProducer {
   @override
-  Iterable<CorrectionProducer> get producers sync* {
+  Stream<CorrectionProducer> get producers async* {
     var targetClassNode = node.thisOrAncestorOfType<ClassDeclaration>();
     if (targetClassNode == null) {
       return;
@@ -76,26 +76,61 @@
   @override
   Future<void> compute(ChangeBuilder builder) async {
     var constructorName = _constructor.name;
-    var requiredParameters = _constructor.parameters
+    var requiredPositionalParameters = _constructor.parameters
         .where((parameter) => parameter.isRequiredPositional);
+    var requiredNamedParameters =
+        _constructor.parameters.where((parameter) => parameter.isRequiredNamed);
     await builder.addDartFileEdit(file, (builder) {
       builder.addInsertion(_targetLocation.offset, (builder) {
-        void writeParameters(bool includeType) {
+        void writeParameters(bool isDefinition) {
+          void writeParameter(ParameterElement parameter) {
+            var parameterName = parameter.displayName;
+            var includeType = isDefinition;
+            var includeRequired = isDefinition && parameter.isRequiredNamed;
+            var includeLabel = !isDefinition && parameter.isRequiredNamed;
+
+            if (parameterName.length > 1 && parameterName.startsWith('_')) {
+              parameterName = parameterName.substring(1);
+            }
+            if (includeRequired) {
+              builder.write('required ');
+            }
+            if (includeType && builder.writeType(parameter.type)) {
+              builder.write(' ');
+            }
+            if (includeLabel) {
+              builder.write('$parameterName: ');
+            }
+            builder.write(parameterName);
+          }
+
           var firstParameter = true;
-          for (var parameter in requiredParameters) {
+          void writeComma() {
             if (firstParameter) {
               firstParameter = false;
             } else {
               builder.write(', ');
             }
-            var parameterName = parameter.displayName;
-            if (parameterName.length > 1 && parameterName.startsWith('_')) {
-              parameterName = parameterName.substring(1);
+          }
+
+          for (var parameter in requiredPositionalParameters) {
+            writeComma();
+            writeParameter(parameter);
+          }
+          if (requiredNamedParameters.isNotEmpty) {
+            var includeBraces = isDefinition;
+            if (includeBraces) {
+              writeComma();
+              firstParameter = true; // Reset since we just included a comma.
+              builder.write('{');
             }
-            if (includeType && builder.writeType(parameter.type)) {
-              builder.write(' ');
+            for (var parameter in requiredNamedParameters) {
+              writeComma();
+              writeParameter(parameter);
             }
-            builder.write(parameterName);
+            if (includeBraces) {
+              builder.write('}');
+            }
           }
         }
 
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/data_driven.dart b/pkg/analysis_server/lib/src/services/correction/dart/data_driven.dart
index ed399ac..029d157 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/data_driven.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/data_driven.dart
@@ -21,7 +21,7 @@
   static List<TransformSet>? transformSetsForTests;
 
   @override
-  Iterable<CorrectionProducer> get producers sync* {
+  Stream<CorrectionProducer> get producers async* {
     var importedUris = <Uri>[];
     var library = resolvedResult.libraryElement;
     for (var importElement in library.imports) {
@@ -92,7 +92,7 @@
     }
     var data = <Object>[];
     for (var change in changes) {
-      var result = change.validate(this);
+      var result = change.validate(this) as Object?;
       if (result == null) {
         return;
       }
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/flutter_convert_to_children.dart b/pkg/analysis_server/lib/src/services/correction/dart/flutter_convert_to_children.dart
index 755c644..7f9a104 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/flutter_convert_to_children.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/flutter_convert_to_children.dart
@@ -42,16 +42,16 @@
   void _convertFlutterChildToChildren(
       NamedExpression namedExp,
       String eol,
-      Function getNodeText,
-      Function getLinePrefix,
-      Function getIndent,
-      Function getText,
+      String Function(Expression) getNodeText,
+      String Function(int) getLinePrefix,
+      String Function(int) getIndent,
+      String Function(int, int) getText,
       FileEditBuilder builder) {
     var childArg = namedExp.expression;
     var childLoc = namedExp.offset + 'child'.length;
     builder.addSimpleInsertion(childLoc, 'ren');
     var listLoc = childArg.offset;
-    String childArgSrc = getNodeText(childArg);
+    var childArgSrc = getNodeText(childArg);
     if (!childArgSrc.contains(eol)) {
       builder.addSimpleInsertion(listLoc, '[');
       builder.addSimpleInsertion(listLoc + childArg.length, ']');
@@ -60,11 +60,10 @@
       if (newlineLoc == childArgSrc.length) {
         newlineLoc -= 1;
       }
-      String indentOld =
-          getLinePrefix(childArg.offset + eol.length + newlineLoc);
+      var indentOld = getLinePrefix(childArg.offset + eol.length + newlineLoc);
       var indentNew = '$indentOld${getIndent(1)}';
       // The separator includes 'child:' but that has no newlines.
-      String separator =
+      var separator =
           getText(namedExp.offset, childArg.offset - namedExp.offset);
       var prefix = separator.contains(eol) ? '' : '$eol$indentNew';
       if (prefix.isEmpty) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/flutter_wrap.dart b/pkg/analysis_server/lib/src/services/correction/dart/flutter_wrap.dart
index 318a934..94a7a71 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/flutter_wrap.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/flutter_wrap.dart
@@ -15,7 +15,7 @@
 
 class FlutterWrap extends MultiCorrectionProducer {
   @override
-  Iterable<CorrectionProducer> get producers sync* {
+  Stream<CorrectionProducer> get producers async* {
     var widgetExpr = flutter.identifyWidgetExpression(node);
     if (widgetExpr != null) {
       var widgetType = widgetExpr.typeOrThrow;
@@ -36,7 +36,7 @@
     yield* _wrapMultipleWidgets();
   }
 
-  Iterable<CorrectionProducer> _wrapMultipleWidgets() sync* {
+  Stream<CorrectionProducer> _wrapMultipleWidgets() async* {
     var selectionRange = SourceRange(selectionOffset, selectionLength);
     var analyzer = SelectionAnalyzer(selectionRange);
     resolvedResult.unit.accept(analyzer);
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/import_library.dart b/pkg/analysis_server/lib/src/services/correction/dart/import_library.dart
index 4a949c4..98cc241 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/import_library.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/import_library.dart
@@ -6,20 +6,18 @@
 
 import 'package:analysis_server/src/services/correction/dart/abstract_producer.dart';
 import 'package:analysis_server/src/services/correction/fix.dart';
-import 'package:analysis_server/src/services/correction/fix/dart/top_level_declarations.dart';
 import 'package:analysis_server/src/services/correction/namespace.dart';
 import 'package:analysis_server/src/services/linter/lint_names.dart';
 import 'package:analysis_server/src/utilities/extensions/element.dart';
-import 'package:analyzer/dart/analysis/results.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/source/source_range.dart';
+import 'package:analyzer/src/dart/resolver/applicable_extensions.dart';
 import 'package:analyzer_plugin/src/utilities/change_builder/change_builder_dart.dart';
 import 'package:analyzer_plugin/src/utilities/library.dart';
 import 'package:analyzer_plugin/utilities/change_builder/change_builder_core.dart';
 import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
-import 'package:analyzer_plugin/utilities/range_factory.dart';
 
 class ImportLibrary extends MultiCorrectionProducer {
   final _ImportKind _importKind;
@@ -27,36 +25,28 @@
   ImportLibrary(this._importKind);
 
   @override
-  Iterable<CorrectionProducer> get producers sync* {
+  Stream<CorrectionProducer> get producers async* {
     final node = this.node;
     if (_importKind == _ImportKind.dartAsync) {
       yield* _importLibrary(DartFixKind.IMPORT_ASYNC, Uri.parse('dart:async'));
     } else if (_importKind == _ImportKind.forExtension) {
       if (node is SimpleIdentifier) {
         var extensionName = node.name;
-        yield* _importLibraryForElement(
-            extensionName,
-            const [ElementKind.EXTENSION],
-            const [TopLevelDeclarationKind.extension]);
+        yield* _importLibraryForElement(extensionName, const [
+          ElementKind.EXTENSION,
+        ]);
       }
     } else if (_importKind == _ImportKind.forExtensionMember) {
       /// Return producers that will import extensions that apply to the
       /// [targetType] and that define a member with the given [memberName].
-      Iterable<CorrectionProducer> importMatchingExtensions(
-          String memberName, DartType? targetType) sync* {
+      Stream<CorrectionProducer> importMatchingExtensions(
+          String memberName, DartType? targetType) async* {
         if (targetType == null) {
           return;
         }
-        var definingLibraries =
-            extensionCache.membersByName[memberName]?.toList();
-        if (definingLibraries != null) {
-          for (var definingLibrary in definingLibraries) {
-            var libraryPath = definingLibrary.libraryPath;
-            var uri = sessionHelper.session.uriConverter.pathToUri(libraryPath);
-            if (uri != null) {
-              yield* _importExtensionInLibrary(uri, targetType, memberName);
-            }
-          }
+        await for (var libraryToImport in librariesWithExtensions(memberName)) {
+          yield* _importExtensionInLibrary(
+              libraryToImport, targetType, memberName);
         }
       }
 
@@ -83,10 +73,7 @@
         var name = node.name;
         yield* _importLibraryForElement(name, const [
           ElementKind.FUNCTION,
-          ElementKind.TOP_LEVEL_VARIABLE
-        ], const [
-          TopLevelDeclarationKind.function,
-          TopLevelDeclarationKind.variable
+          ElementKind.TOP_LEVEL_VARIABLE,
         ]);
       }
     } else if (_importKind == _ImportKind.forTopLevelVariable) {
@@ -102,10 +89,9 @@
       }
       if (targetNode is SimpleIdentifier) {
         var name = targetNode.name;
-        yield* _importLibraryForElement(
-            name,
-            const [ElementKind.TOP_LEVEL_VARIABLE],
-            const [TopLevelDeclarationKind.variable]);
+        yield* _importLibraryForElement(name, const [
+          ElementKind.TOP_LEVEL_VARIABLE,
+        ]);
       }
     } else if (_importKind == _ImportKind.forType) {
       var targetNode = node;
@@ -124,15 +110,15 @@
             : (targetNode as PrefixedIdentifier).prefix.name;
         yield* _importLibraryForElement(typeName, const [
           ElementKind.CLASS,
+          ElementKind.ENUM,
           ElementKind.FUNCTION_TYPE_ALIAS,
-          ElementKind.TYPE_ALIAS
-        ], const [
-          TopLevelDeclarationKind.type
+          ElementKind.TYPE_ALIAS,
         ]);
       } else if (mightBeImplicitConstructor(targetNode)) {
         var typeName = (targetNode as SimpleIdentifier).name;
-        yield* _importLibraryForElement(typeName, const [ElementKind.CLASS],
-            const [TopLevelDeclarationKind.type]);
+        yield* _importLibraryForElement(typeName, const [
+          ElementKind.CLASS,
+        ]);
       }
     }
   }
@@ -151,8 +137,11 @@
     return false;
   }
 
-  Iterable<CorrectionProducer> _importExtensionInLibrary(
-      Uri uri, DartType targetType, String memberName) sync* {
+  Stream<CorrectionProducer> _importExtensionInLibrary(
+    LibraryElement libraryToImport,
+    DartType targetType,
+    String memberName,
+  ) async* {
     // Look to see whether the library at the [uri] is already imported. If it
     // is, then we can check the extension elements without needing to perform
     // additional analysis.
@@ -160,12 +149,17 @@
     for (var imp in libraryElement.imports) {
       // prepare element
       var importedLibrary = imp.importedLibrary;
-      if (importedLibrary == null || importedLibrary.source.uri != uri) {
+      if (importedLibrary == null || importedLibrary != libraryToImport) {
         continue;
       }
       foundImport = true;
-      for (var extension in importedLibrary.matchingExtensionsWithMember(
-          libraryElement, targetType, memberName)) {
+      var instantiatedExtensions = importedLibrary.exportedExtensions
+          .hasMemberWithBaseName(memberName)
+          .applicableTo(
+            targetLibrary: libraryElement,
+            targetType: targetType,
+          );
+      for (var instantiatedExtension in instantiatedExtensions) {
         // If the import has a combinator that needs to be updated, then offer
         // to update it.
         var combinators = imp.combinators;
@@ -175,8 +169,8 @@
             // TODO(brianwilkerson) Support removing the extension name from a
             //  hide combinator.
           } else if (combinator is ShowElementCombinator) {
-            yield _ImportLibraryShow(
-                uri.toString(), combinator, extension.name!);
+            yield _ImportLibraryShow(libraryToImport.source.uri.toString(),
+                combinator, instantiatedExtension.extension.name!);
           }
         }
       }
@@ -186,7 +180,8 @@
     // correction producer that will either add an import or not based on the
     // result of analyzing the library.
     if (!foundImport) {
-      yield _ImportLibraryContainingExtension(uri, targetType, memberName);
+      yield _ImportLibraryContainingExtension(
+          libraryToImport, targetType, memberName);
     }
   }
 
@@ -197,38 +192,40 @@
   /// path and a correction with a relative path are returned. If the
   /// `prefer_relative_imports` lint rule is enabled, the relative path is
   /// returned first.
-  Iterable<CorrectionProducer> _importLibrary(
+  Stream<CorrectionProducer> _importLibrary(
     FixKind fixKind,
     Uri library, {
     bool includeRelativeFix = false,
   }) {
     if (!includeRelativeFix) {
-      return [_ImportAbsoluteLibrary(fixKind, library)];
+      return Stream.fromIterable([
+        _ImportAbsoluteLibrary(fixKind, library),
+      ]);
     }
     if (isLintEnabled(LintNames.prefer_relative_imports)) {
-      return [
+      return Stream.fromIterable([
         _ImportRelativeLibrary(fixKind, library),
         _ImportAbsoluteLibrary(fixKind, library),
-      ];
+      ]);
     } else {
-      return [
+      return Stream.fromIterable([
         _ImportAbsoluteLibrary(fixKind, library),
         _ImportRelativeLibrary(fixKind, library),
-      ];
+      ]);
     }
   }
 
-  Iterable<CorrectionProducer> _importLibraryForElement(
-      String name,
-      List<ElementKind> elementKinds,
-      List<TopLevelDeclarationKind> kinds2) sync* {
+  Stream<CorrectionProducer> _importLibraryForElement(
+    String name,
+    List<ElementKind> kinds,
+  ) async* {
     // ignore if private
     if (name.startsWith('_')) {
       return;
     }
     // may be there is an existing import,
     // but it is with prefix and we don't use this prefix
-    var alreadyImportedWithPrefix = <String>{};
+    var alreadyImportedWithPrefix = <LibraryElement>{};
     for (var imp in libraryElement.imports) {
       // prepare element
       var libraryElement = imp.importedLibrary;
@@ -242,7 +239,7 @@
       if (element is PropertyAccessorElement) {
         element = element.variable;
       }
-      if (!elementKinds.contains(element.kind)) {
+      if (!kinds.contains(element.kind)) {
         continue;
       }
       // may be apply prefix
@@ -266,34 +263,37 @@
             libraryName = libraryElement.source.shortName;
           }
           // don't add this library again
-          alreadyImportedWithPrefix.add(libraryElement.source.fullName);
+          alreadyImportedWithPrefix.add(libraryElement);
           yield _ImportLibraryShow(libraryName, combinator, name);
         }
       }
     }
     // Find new top-level declarations.
-    var declarations = getTopLevelDeclarations(name);
-    for (var declaration in declarations) {
+    var librariesWithElements = await getTopLevelDeclarations(name);
+    for (var libraryEntry in librariesWithElements.entries) {
+      var libraryElement = libraryEntry.key;
+      var declaration = libraryEntry.value;
+      var librarySource = libraryElement.source;
       // Check the kind.
-      if (!kinds2.contains(declaration.kind)) {
+      if (!kinds.contains(declaration.kind)) {
         continue;
       }
       // Check the source.
-      if (alreadyImportedWithPrefix.contains(declaration.path)) {
+      if (alreadyImportedWithPrefix.contains(libraryElement)) {
         continue;
       }
       // Check that the import doesn't end with '.template.dart'
-      if (declaration.uri.path.endsWith('.template.dart')) {
+      if (librarySource.uri.path.endsWith('.template.dart')) {
         continue;
       }
       // Compute the fix kind.
       FixKind fixKind;
-      if (declaration.uri.isScheme('dart')) {
+      if (librarySource.uri.isScheme('dart')) {
         fixKind = DartFixKind.IMPORT_LIBRARY_SDK;
-      } else if (_isLibSrcPath(declaration.path)) {
+      } else if (_isLibSrcPath(librarySource.fullName)) {
         // Bad: non-API.
         fixKind = DartFixKind.IMPORT_LIBRARY_PROJECT3;
-      } else if (declaration.isExported) {
+      } else if (declaration.library != libraryElement) {
         // Ugly: exports.
         fixKind = DartFixKind.IMPORT_LIBRARY_PROJECT2;
       } else {
@@ -303,9 +303,9 @@
       // If both files are in the same package's lib folder, also include a
       // relative import.
       var includeRelativeUri = canBeRelativeImport(
-          declaration.uri, libraryElement.librarySource.uri);
+          librarySource.uri, this.libraryElement.librarySource.uri);
       // Add the fix(es).
-      yield* _importLibrary(fixKind, declaration.uri,
+      yield* _importLibrary(fixKind, librarySource.uri,
           includeRelativeFix: includeRelativeUri);
     }
   }
@@ -342,6 +342,8 @@
         return parent.declaredElement?.thisType;
       } else if (parent is ExtensionDeclaration) {
         return parent.extendedType.type;
+      } else {
+        return null;
       }
     }
 
@@ -359,6 +361,8 @@
       }
       parent = parent.parent;
     }
+
+    return null;
   }
 
   /// Return an instance of this class that will add an import of `dart:async`.
@@ -425,8 +429,8 @@
 /// A correction processor that can add an import of a library containing an
 /// extension, but which does so only if the extension applies to a given type.
 class _ImportLibraryContainingExtension extends CorrectionProducer {
-  /// The URI of the library defining the extension.
-  Uri uri;
+  /// The library defining the extension.
+  LibraryElement library;
 
   /// The type of the target that the extension must apply to.
   DartType targetType;
@@ -437,7 +441,11 @@
   /// The URI that is being proposed for the import directive.
   String _uriText = '';
 
-  _ImportLibraryContainingExtension(this.uri, this.targetType, this.memberName);
+  _ImportLibraryContainingExtension(
+    this.library,
+    this.targetType,
+    this.memberName,
+  );
 
   @override
   List<Object> get fixArguments => [_uriText];
@@ -447,16 +455,16 @@
 
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    var result = await sessionHelper.session.getLibraryByUri(uri.toString());
-    if (result is LibraryElementResult) {
-      var library = result.element;
-      if (library
-          .matchingExtensionsWithMember(libraryElement, targetType, memberName)
-          .isNotEmpty) {
-        await builder.addDartFileEdit(file, (builder) {
-          _uriText = builder.importLibrary(uri);
-        });
-      }
+    var instantiatedExtensions = library.exportedExtensions
+        .hasMemberWithBaseName(memberName)
+        .applicableTo(
+          targetLibrary: libraryElement,
+          targetType: targetType,
+        );
+    if (instantiatedExtensions.isNotEmpty) {
+      await builder.addDartFileEdit(file, (builder) {
+        _uriText = builder.importLibrary(library.source.uri);
+      });
     }
   }
 }
@@ -467,24 +475,23 @@
   final LibraryElement _importedLibrary;
   final PrefixElement _importPrefix;
 
-  String _libraryName = '';
-
-  String _prefixName = '';
-
   _ImportLibraryPrefix(this._importedLibrary, this._importPrefix);
 
   @override
-  List<Object> get fixArguments => [_libraryName, _prefixName];
+  List<Object> get fixArguments {
+    var uriStr = _importedLibrary.source.uri.toString();
+    return [uriStr, _prefixName];
+  }
 
   @override
   FixKind get fixKind => DartFixKind.IMPORT_LIBRARY_PREFIX;
 
+  String get _prefixName => _importPrefix.name;
+
   @override
   Future<void> compute(ChangeBuilder builder) async {
-    _libraryName = _importedLibrary.displayName;
-    _prefixName = _importPrefix.displayName;
     await builder.addDartFileEdit(file, (builder) {
-      builder.addSimpleReplacement(range.startLength(node, 0), '$_prefixName.');
+      builder.addSimpleInsertion(node.offset, '$_prefixName.');
     });
   }
 }
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_future.dart b/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_future.dart
index fb29e4f..9d3b8dd 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_future.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_future.dart
@@ -9,6 +9,12 @@
 import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
 
 class ReplaceReturnTypeFuture extends CorrectionProducer {
+  /// The text for the type argument to 'Future'.
+  String _typeArgument = '';
+
+  @override
+  List<Object>? get fixArguments => [_typeArgument];
+
   @override
   FixKind get fixKind => DartFixKind.REPLACE_RETURN_TYPE_FUTURE;
 
@@ -19,6 +25,7 @@
     if (typeAnnotation == null) {
       return;
     }
+    _typeArgument = utils.getNodeText(typeAnnotation);
 
     await builder.addDartFileEdit(file, (builder) {
       builder.replaceTypeWithFuture(typeAnnotation, typeProvider);
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_iterable.dart b/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_iterable.dart
new file mode 100644
index 0000000..cc491aa
--- /dev/null
+++ b/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_iterable.dart
@@ -0,0 +1,44 @@
+// Copyright (c) 2020, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analysis_server/src/services/correction/dart/abstract_producer.dart';
+import 'package:analysis_server/src/services/correction/fix.dart';
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer_plugin/utilities/change_builder/change_builder_core.dart';
+import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
+import 'package:analyzer_plugin/utilities/range_factory.dart';
+
+class ReplaceReturnTypeIterable extends CorrectionProducer {
+  /// The text for the type argument to 'Iterable'.
+  String _typeArgument = '';
+
+  @override
+  List<Object>? get fixArguments => [_typeArgument];
+
+  @override
+  FixKind get fixKind => DartFixKind.REPLACE_RETURN_TYPE_ITERABLE;
+
+  @override
+  Future<void> compute(ChangeBuilder builder) async {
+    // prepare the existing type
+    var typeAnnotation = node.thisOrAncestorOfType<TypeAnnotation>();
+    if (typeAnnotation == null) {
+      return;
+    }
+    var type = typeAnnotation.type;
+    if (type == null || type.isDynamic || type.isDartCoreIterable) {
+      return;
+    }
+    _typeArgument = utils.getNodeText(typeAnnotation);
+
+    await builder.addDartFileEdit(file, (builder) {
+      builder.addReplacement(range.node(typeAnnotation), (builder) {
+        builder.writeType(typeProvider.iterableType(type));
+      });
+    });
+  }
+
+  /// Return an instance of this class. Used as a tear-off in `FixProcessor`.
+  static ReplaceReturnTypeIterable newInstance() => ReplaceReturnTypeIterable();
+}
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_stream.dart b/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_stream.dart
new file mode 100644
index 0000000..829ebe6
--- /dev/null
+++ b/pkg/analysis_server/lib/src/services/correction/dart/replace_return_type_stream.dart
@@ -0,0 +1,44 @@
+// Copyright (c) 2020, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analysis_server/src/services/correction/dart/abstract_producer.dart';
+import 'package:analysis_server/src/services/correction/fix.dart';
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer_plugin/utilities/change_builder/change_builder_core.dart';
+import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
+import 'package:analyzer_plugin/utilities/range_factory.dart';
+
+class ReplaceReturnTypeStream extends CorrectionProducer {
+  /// The text for the type argument to 'Stream'.
+  String _typeArgument = '';
+
+  @override
+  List<Object>? get fixArguments => [_typeArgument];
+
+  @override
+  FixKind get fixKind => DartFixKind.REPLACE_RETURN_TYPE_STREAM;
+
+  @override
+  Future<void> compute(ChangeBuilder builder) async {
+    // prepare the existing type
+    var typeAnnotation = node.thisOrAncestorOfType<TypeAnnotation>();
+    if (typeAnnotation == null) {
+      return;
+    }
+    var type = typeAnnotation.type;
+    if (type == null || type.isDynamic || type.isDartAsyncStream) {
+      return;
+    }
+    _typeArgument = utils.getNodeText(typeAnnotation);
+
+    await builder.addDartFileEdit(file, (builder) {
+      builder.addReplacement(range.node(typeAnnotation), (builder) {
+        builder.writeType(typeProvider.streamType(type));
+      });
+    });
+  }
+
+  /// Return an instance of this class. Used as a tear-off in `FixProcessor`.
+  static ReplaceReturnTypeStream newInstance() => ReplaceReturnTypeStream();
+}
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/surround_with.dart b/pkg/analysis_server/lib/src/services/correction/dart/surround_with.dart
index 84d8648..87abf94 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/surround_with.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/surround_with.dart
@@ -12,7 +12,7 @@
 
 class SurroundWith extends MultiCorrectionProducer {
   @override
-  Iterable<CorrectionProducer> get producers sync* {
+  Stream<CorrectionProducer> get producers async* {
     // If the node is the CompilationUnit, the selected statements must span multiple
     // top level items and cannot be surrounded with anything.
     if (node is CompilationUnit) {
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/update_sdk_constraints.dart b/pkg/analysis_server/lib/src/services/correction/dart/update_sdk_constraints.dart
index c12a2e2..e3acc88 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/update_sdk_constraints.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/update_sdk_constraints.dart
@@ -77,6 +77,7 @@
         return pubspecFile;
       }
     }
+    return null;
   }
 
   /// Return an instance of this class that will update the SDK constraints to
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/wrap_in_text.dart b/pkg/analysis_server/lib/src/services/correction/dart/wrap_in_text.dart
index 53c87c90..9915a0a 100644
--- a/pkg/analysis_server/lib/src/services/correction/dart/wrap_in_text.dart
+++ b/pkg/analysis_server/lib/src/services/correction/dart/wrap_in_text.dart
@@ -62,6 +62,8 @@
         }
       }
     }
+
+    return null;
   }
 }
 
diff --git a/pkg/analysis_server/lib/src/services/correction/fix.dart b/pkg/analysis_server/lib/src/services/correction/fix.dart
index 84a648c..666ea13 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix.dart
@@ -3,10 +3,11 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:analysis_server/plugin/edit/fix/fix_dart.dart';
-import 'package:analysis_server/src/services/completion/dart/extension_cache.dart';
+import 'package:analysis_server/src/services/correction/fix/dart/extensions.dart';
 import 'package:analysis_server/src/services/correction/fix/dart/top_level_declarations.dart';
 import 'package:analysis_server/src/services/correction/fix_internal.dart';
 import 'package:analyzer/dart/analysis/results.dart';
+import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/instrumentation/service.dart';
 import 'package:analyzer/src/error/codes.dart';
@@ -55,20 +56,18 @@
   @override
   final AnalysisError error;
 
-  @override
-  final ExtensionCache extensionCache;
-
-  final List<TopLevelDeclaration> Function(String name)
-      getTopLevelDeclarationsFunction;
-
   DartFixContextImpl(this.instrumentationService, this.workspace,
-      this.resolveResult, this.error, this.getTopLevelDeclarationsFunction,
-      {ExtensionCache? extensionCache})
-      : extensionCache = extensionCache ?? ExtensionCache();
+      this.resolveResult, this.error);
 
   @override
-  List<TopLevelDeclaration> getTopLevelDeclarations(String name) {
-    return getTopLevelDeclarationsFunction(name);
+  Future<Map<LibraryElement, Element>> getTopLevelDeclarations(
+      String name) async {
+    return TopLevelDeclarations(resolveResult).withName(name);
+  }
+
+  @override
+  Stream<LibraryElement> librariesWithExtensions(String memberName) {
+    return Extensions(resolveResult).libraries(memberName);
   }
 }
 
@@ -214,6 +213,16 @@
     DartFixKindPriority.IN_FILE,
     "Add 'required' keywords everywhere in file",
   );
+  static const ADD_RETURN_NULL = FixKind(
+    'dart.fix.add.returnNull',
+    DartFixKindPriority.DEFAULT,
+    "Add 'return null'",
+  );
+  static const ADD_RETURN_NULL_MULTI = FixKind(
+    'dart.fix.add.returnNull.multi',
+    DartFixKindPriority.IN_FILE,
+    "Add 'return null' everywhere in file",
+  );
   static const ADD_RETURN_TYPE = FixKind(
     'dart.fix.add.returnType',
     DartFixKindPriority.DEFAULT,
@@ -1252,7 +1261,17 @@
   static const REPLACE_RETURN_TYPE_FUTURE = FixKind(
     'dart.fix.replace.returnTypeFuture',
     DartFixKindPriority.DEFAULT,
-    "Return 'Future' from 'async' function",
+    "Return 'Future<{0}>'",
+  );
+  static const REPLACE_RETURN_TYPE_ITERABLE = FixKind(
+    'dart.fix.replace.returnTypeIterable',
+    DartFixKindPriority.DEFAULT,
+    "Return 'Iterable<{0}>'",
+  );
+  static const REPLACE_RETURN_TYPE_STREAM = FixKind(
+    'dart.fix.replace.returnTypeStream',
+    DartFixKindPriority.DEFAULT,
+    "Return 'Stream<{0}>'",
   );
   static const REPLACE_CONTAINER_WITH_SIZED_BOX = FixKind(
     'dart.fix.replace.containerWithSizedBox',
diff --git a/pkg/analysis_server/lib/src/services/correction/fix/analysis_options/fix_generator.dart b/pkg/analysis_server/lib/src/services/correction/fix/analysis_options/fix_generator.dart
index d3b6ac3..8c148db 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix/analysis_options/fix_generator.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix/analysis_options/fix_generator.dart
@@ -151,7 +151,7 @@
           } else if (nodes.containsValue(child)) {
             for (var entry in nodes.entries) {
               if (child == entry.value) {
-                key = entry.key;
+                key = entry.key as YamlNode?;
                 value = child;
                 break;
               }
diff --git a/pkg/analysis_server/lib/src/services/correction/fix/dart/extensions.dart b/pkg/analysis_server/lib/src/services/correction/fix/dart/extensions.dart
new file mode 100644
index 0000000..b613ec7
--- /dev/null
+++ b/pkg/analysis_server/lib/src/services/correction/fix/dart/extensions.dart
@@ -0,0 +1,47 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:async';
+
+import 'package:analyzer/dart/analysis/results.dart';
+import 'package:analyzer/dart/element/element.dart';
+import 'package:analyzer/src/dart/analysis/driver_based_analysis_context.dart';
+import 'package:analyzer/src/dart/analysis/file_state_filter.dart';
+
+class Extensions {
+  final ResolvedUnitResult resolvedUnit;
+
+  Extensions(this.resolvedUnit);
+
+  DriverBasedAnalysisContext get _analysisContext {
+    var analysisContext = resolvedUnit.session.analysisContext;
+    return analysisContext as DriverBasedAnalysisContext;
+  }
+
+  /// Return libraries that may be imported into the [resolvedUnit] file,
+  /// and might have extensions that define a non-static public member with
+  /// the [memberName].
+  Stream<LibraryElement> libraries(String memberName) async* {
+    var analysisDriver = _analysisContext.driver;
+    await analysisDriver.discoverAvailableFiles();
+
+    var fsState = analysisDriver.fsState;
+    var filter = FileStateFilter(
+      fsState.getFileForPath(resolvedUnit.path),
+    );
+
+    for (var file in fsState.knownFiles.toList()) {
+      if (!filter.shouldInclude(file)) {
+        continue;
+      }
+
+      var libraryElement = analysisDriver.getLibraryByFile(file);
+      if (libraryElement == null) {
+        continue;
+      }
+
+      yield libraryElement;
+    }
+  }
+}
diff --git a/pkg/analysis_server/lib/src/services/correction/fix/dart/top_level_declarations.dart b/pkg/analysis_server/lib/src/services/correction/fix/dart/top_level_declarations.dart
index 3bc6161..0106ff1 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix/dart/top_level_declarations.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix/dart/top_level_declarations.dart
@@ -2,108 +2,70 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'package:analyzer/dart/analysis/analysis_context.dart';
-import 'package:analyzer/src/services/available_declarations.dart';
+import 'dart:async';
 
-/// Information about a single top-level declaration.
-class TopLevelDeclaration {
-  /// The path of the library that exports this declaration.
-  final String path;
+import 'package:analyzer/dart/analysis/results.dart';
+import 'package:analyzer/dart/element/element.dart';
+import 'package:analyzer/src/dart/analysis/driver_based_analysis_context.dart';
+import 'package:analyzer/src/dart/analysis/file_state_filter.dart';
 
-  /// The URI of the library that exports this declaration.
-  final Uri uri;
+class TopLevelDeclarations {
+  final ResolvedUnitResult resolvedUnit;
 
-  final TopLevelDeclarationKind kind;
+  TopLevelDeclarations(this.resolvedUnit);
 
-  final String name;
-
-  /// Is `true` if the declaration is exported, not declared in the [path].
-  final bool isExported;
-
-  TopLevelDeclaration(
-    this.path,
-    this.uri,
-    this.kind,
-    this.name,
-    this.isExported,
-  );
-
-  @override
-  String toString() => '($path, $uri, $kind, $name, $isExported)';
-}
-
-/// Kind of a top-level declaration.
-///
-/// We don't need it to be precise, just enough to support quick fixes.
-enum TopLevelDeclarationKind { type, extension, function, variable }
-
-class TopLevelDeclarationsProvider {
-  final DeclarationsTracker tracker;
-
-  TopLevelDeclarationsProvider(this.tracker);
-
-  void doTrackerWork() {
-    while (tracker.hasWork) {
-      tracker.doWork();
-    }
+  DriverBasedAnalysisContext get _analysisContext {
+    var analysisContext = resolvedUnit.session.analysisContext;
+    return analysisContext as DriverBasedAnalysisContext;
   }
 
-  List<TopLevelDeclaration> get(
-    AnalysisContext analysisContext,
-    String path,
-    String name,
+  /// Return the mapping from a library (that is available to this context) to
+  /// a top-level declaration that is exported (not necessary declared) by this
+  /// library, and has the requested base name. For getters and setters the
+  /// corresponding top-level variable is returned.
+  Future<Map<LibraryElement, Element>> withName(String baseName) async {
+    var analysisDriver = _analysisContext.driver;
+    await analysisDriver.discoverAvailableFiles();
+
+    var fsState = analysisDriver.fsState;
+    var filter = FileStateFilter(
+      fsState.getFileForPath(resolvedUnit.path),
+    );
+
+    var result = <LibraryElement, Element>{};
+
+    for (var file in fsState.knownFiles.toList()) {
+      if (!filter.shouldInclude(file)) {
+        continue;
+      }
+
+      var libraryElement = analysisDriver.getLibraryByFile(file);
+      if (libraryElement == null) {
+        continue;
+      }
+
+      addElement(result, libraryElement, baseName);
+    }
+
+    return result;
+  }
+
+  static void addElement(
+    Map<LibraryElement, Element> result,
+    LibraryElement libraryElement,
+    String baseName,
   ) {
-    var declarations = <TopLevelDeclaration>[];
-
-    void addDeclarations(Library library) {
-      for (var declaration in library.declarations) {
-        if (declaration.name != name) continue;
-
-        var kind = _getTopKind(declaration.kind);
-        if (kind == null) continue;
-
-        declarations.add(
-          TopLevelDeclaration(
-            library.path,
-            library.uri,
-            kind,
-            name,
-            declaration.locationLibraryUri != library.uri,
-          ),
-        );
+    void addSingle(String name) {
+      var element = libraryElement.exportNamespace.get(name);
+      if (element is PropertyAccessorElement) {
+        element = element.variable;
+      }
+      if (element != null) {
+        result[libraryElement] = element;
       }
     }
 
-    var declarationsContext = tracker.getContext(analysisContext);
-    if (declarationsContext == null) return const [];
-
-    var libraries = declarationsContext.getLibraries(path);
-    libraries.context.forEach(addDeclarations);
-    libraries.dependencies.forEach(addDeclarations);
-    libraries.sdk.forEach(addDeclarations);
-
-    return declarations;
-  }
-
-  TopLevelDeclarationKind? _getTopKind(DeclarationKind kind) {
-    switch (kind) {
-      case DeclarationKind.CLASS:
-      case DeclarationKind.CLASS_TYPE_ALIAS:
-      case DeclarationKind.ENUM:
-      case DeclarationKind.FUNCTION_TYPE_ALIAS:
-      case DeclarationKind.TYPE_ALIAS:
-      case DeclarationKind.MIXIN:
-        return TopLevelDeclarationKind.type;
-      case DeclarationKind.EXTENSION:
-        return TopLevelDeclarationKind.extension;
-      case DeclarationKind.FUNCTION:
-        return TopLevelDeclarationKind.function;
-      case DeclarationKind.GETTER:
-      case DeclarationKind.SETTER:
-      case DeclarationKind.VARIABLE:
-        return TopLevelDeclarationKind.variable;
-      default:
-        return null;
-    }
+    addSingle(baseName);
+    addSingle('$baseName=');
   }
 }
diff --git a/pkg/analysis_server/lib/src/services/correction/fix/data_driven/element_descriptor.dart b/pkg/analysis_server/lib/src/services/correction/fix/data_driven/element_descriptor.dart
index 4b9619d..e512626 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix/data_driven/element_descriptor.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix/data_driven/element_descriptor.dart
@@ -7,7 +7,7 @@
 import 'package:analyzer/dart/element/element.dart' show ClassElement;
 import 'package:analyzer/dart/element/type.dart';
 
-/// The path to an element.
+/// A description of an element.
 class ElementDescriptor {
   /// The URIs of the library in which the element is defined.
   final List<Uri> libraryUris;
@@ -15,6 +15,14 @@
   /// The kind of element that was changed.
   final ElementKind kind;
 
+  /// A flag indicating whether the element is a static member of a container
+  /// such as a class, enum, mixin, or extension.
+  ///
+  /// The flag should be `false` for top-level declarations. The implication is
+  /// that the flag will only be true if the list of [components] has more than
+  /// one element.
+  final bool isStatic;
+
   /// The components that uniquely identify the element within its library. The
   /// components are ordered from the most local to the most global.
   final List<String> components;
@@ -26,122 +34,139 @@
   ElementDescriptor(
       {required this.libraryUris,
       required this.kind,
+      required this.isStatic,
       required this.components});
 
   /// Return `true` if the described element is a constructor.
   bool get isConstructor => kind == ElementKind.constructorKind;
 
-  /// Return `true` if the given [node] appears to be consistent with this kind
-  /// of element.
+  /// Return `true` if the given [node] appears to be consistent with the
+  /// element being described.
   bool matches(AstNode node) {
-    // TODO(brianwilkerson) Check the resolved element if one exists for more
+    // TODO(brianwilkerson) Check the resolved element, if one exists, for more
     //  accurate results.
     switch (kind) {
       case ElementKind.classKind:
-        // TODO: Handle this case.
+        // TODO(brianwilkerson) Handle this case.
         return false;
       case ElementKind.constantKind:
-        // TODO: Handle this case.
+        // TODO(brianwilkerson) Handle this case.
         return false;
       case ElementKind.constructorKind:
-        if (node is Annotation) {
-          var className = _nameFromIdentifier(node.name);
-          var constructorName = node.constructorName ?? '';
-          if (components[0] == constructorName && components[1] == className) {
-            return true;
-          }
-        } else if (node is InstanceCreationExpression) {
-          var name = node.constructorName;
-          var className = _nameFromIdentifier(name.type2.name);
-          var constructorName = name.name?.name ?? '';
-          if (components[0] == constructorName && components[1] == className) {
-            return true;
-          }
-        } else if (node is MethodInvocation) {
-          var target = node.target;
-          if (target == null) {
-            if (components[0] == '' && components[1] == node.methodName.name) {
-              return true;
-            }
-          } else if (target is Identifier) {
-            var className = _nameFromIdentifier(target);
-            var constructorName = node.methodName.name;
-            if (components[0] == constructorName &&
-                components[1] == className) {
-              return true;
-            }
-          }
-        }
-        return false;
+        return _matchesConstructor(node);
       case ElementKind.enumKind:
-        // TODO: Handle this case.
+        // TODO(brianwilkerson) Handle this case.
         return false;
       case ElementKind.extensionKind:
-        // TODO: Handle this case.
+        // TODO(brianwilkerson) Handle this case.
         return false;
       case ElementKind.fieldKind:
-        // TODO: Handle this case.
+        // TODO(brianwilkerson) Handle this case.
         return false;
       case ElementKind.functionKind:
-        if (node is MethodInvocation) {
-          if (node.realTarget == null &&
-              components[0] == node.methodName.name) {
-            return true;
-          }
-        }
-        return false;
+        return _matchesFunction(node);
       case ElementKind.getterKind:
-        // TODO: Handle this case.
+        // TODO(brianwilkerson) Handle this case.
         return false;
       case ElementKind.methodKind:
-        if (node is MethodInvocation) {
-          if (components[0] == node.methodName.name) {
-            var target = node.realTarget;
-            if (target == null) {
-              // TODO(brianwilkerson) If `node.target == null` then the invocation
-              //  should be in a subclass of the element's class.
-              return true;
-            } else {
-              var type = target.staticType;
-              if (type == null && target is SimpleIdentifier) {
-                var element = target.staticElement;
-                // TODO(brianwilkerson) Handle more than `ClassElement`.
-                if (element is ClassElement) {
-                  type = element.thisType;
-                }
-              }
-              if (type == null) {
-                // We can't get more specific type information, so we assume
-                // that the method might have been in the element's class.
+        return _matchesMethod(node);
+      case ElementKind.mixinKind:
+        // TODO(brianwilkerson) Handle this case.
+        return false;
+      case ElementKind.setterKind:
+        // TODO(brianwilkerson) Handle this case.
+        return false;
+      case ElementKind.typedefKind:
+        // TODO(brianwilkerson) Handle this case.
+        return false;
+      case ElementKind.variableKind:
+        // TODO(brianwilkerson) Handle this case.
+        return false;
+    }
+  }
+
+  /// Return `true` if the given [node] appears to be consistent with the
+  /// constructor being described.
+  bool _matchesConstructor(AstNode node) {
+    if (node is Annotation) {
+      var className = _nameFromIdentifier(node.name);
+      var constructorName = node.constructorName ?? '';
+      if (components[0] == constructorName && components[1] == className) {
+        return true;
+      }
+    } else if (node is InstanceCreationExpression) {
+      var name = node.constructorName;
+      var className = _nameFromIdentifier(name.type2.name);
+      var constructorName = name.name?.name ?? '';
+      if (components[0] == constructorName && components[1] == className) {
+        return true;
+      }
+    } else if (node is MethodInvocation) {
+      var target = node.target;
+      if (target == null) {
+        if (components[0] == '' && components[1] == node.methodName.name) {
+          return true;
+        }
+      } else if (target is Identifier) {
+        var className = _nameFromIdentifier(target);
+        var constructorName = node.methodName.name;
+        if (components[0] == constructorName && components[1] == className) {
+          return true;
+        }
+      }
+    }
+    return false;
+  }
+
+  /// Return `true` if the given [node] appears to be consistent with the
+  /// function being described.
+  bool _matchesFunction(AstNode node) {
+    if (node is MethodInvocation) {
+      if (node.realTarget == null && components[0] == node.methodName.name) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  /// Return `true` if the given [node] appears to be consistent with the
+  /// method being described.
+  bool _matchesMethod(AstNode node) {
+    if (node is MethodInvocation) {
+      if (components[0] == node.methodName.name) {
+        var target = node.realTarget;
+        if (target == null) {
+          // TODO(brianwilkerson) If `node.target == null` then the invocation
+          //  should be in a subclass of the element's class.
+          return true;
+        } else {
+          var type = target.staticType;
+          if (type == null && target is SimpleIdentifier) {
+            var element = target.staticElement;
+            // TODO(brianwilkerson) Handle more than `ClassElement`.
+            if (element is ClassElement) {
+              type = element.thisType;
+            }
+          }
+          if (type == null) {
+            // We can't get more specific type information, so we assume
+            // that the method might have been in the element's class.
+            return true;
+          }
+          if (components[1] == type.element?.name) {
+            return true;
+          }
+          if (type is InterfaceType) {
+            for (var supertype in type.allSupertypes) {
+              if (components[1] == supertype.element.name) {
                 return true;
               }
-              if (components[1] == type.element?.name) {
-                return true;
-              }
-              if (type is InterfaceType) {
-                for (var supertype in type.allSupertypes) {
-                  if (components[1] == supertype.element.name) {
-                    return true;
-                  }
-                }
-              }
             }
           }
         }
-        return false;
-      case ElementKind.mixinKind:
-        // TODO: Handle this case.
-        return false;
-      case ElementKind.setterKind:
-        // TODO: Handle this case.
-        return false;
-      case ElementKind.typedefKind:
-        // TODO: Handle this case.
-        return false;
-      case ElementKind.variableKind:
-        // TODO: Handle this case.
-        return false;
+      }
     }
+    return false;
   }
 
   String _nameFromIdentifier(Identifier identifier) {
diff --git a/pkg/analysis_server/lib/src/services/correction/fix/data_driven/rename_parameter.dart b/pkg/analysis_server/lib/src/services/correction/fix/data_driven/rename_parameter.dart
index 1072578..19ca94a 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix/data_driven/rename_parameter.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix/data_driven/rename_parameter.dart
@@ -111,20 +111,6 @@
 }
 
 extension on MethodDeclaration {
-  /// Return the parameter of this method whose name matches the given [name],
-  /// or `null` if there is no such parameter.
-  FormalParameter? parameterNamed(String name) {
-    final parameters = this.parameters;
-    if (parameters != null) {
-      for (var parameter in parameters.parameters) {
-        if (parameter.declaredElement?.name == name) {
-          return parameter;
-        }
-      }
-    }
-    return null;
-  }
-
   /// Return the element that this method overrides, or `null` if this method
   /// doesn't override any inherited member.
   ExecutableElement? overriddenElement() {
@@ -138,6 +124,20 @@
     }
     return null;
   }
+
+  /// Return the parameter of this method whose name matches the given [name],
+  /// or `null` if there is no such parameter.
+  FormalParameter? parameterNamed(String name) {
+    final parameters = this.parameters;
+    if (parameters != null) {
+      for (var parameter in parameters.parameters) {
+        if (parameter.declaredElement?.name == name) {
+          return parameter;
+        }
+      }
+    }
+    return null;
+  }
 }
 
 extension on ExecutableElement {
diff --git a/pkg/analysis_server/lib/src/services/correction/fix/data_driven/transform_override_set_parser.dart b/pkg/analysis_server/lib/src/services/correction/fix/data_driven/transform_override_set_parser.dart
index aec5cc03..8eb7537 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix/data_driven/transform_override_set_parser.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix/data_driven/transform_override_set_parser.dart
@@ -91,6 +91,7 @@
   /// Report any keys in the [map] whose values are not in [validKeys].
   void _reportUnsupportedKeys(YamlMap map, Set<String> validKeys) {
     for (var keyNode in map.nodes.keys) {
+      keyNode as YamlNode;
       var key = _translateKey(keyNode);
       if (key != null && !validKeys.contains(key)) {
         _reportError(TransformSetErrorCode.unsupportedKey, keyNode, [key]);
diff --git a/pkg/analysis_server/lib/src/services/correction/fix/data_driven/transform_set_error_code.dart b/pkg/analysis_server/lib/src/services/correction/fix/data_driven/transform_set_error_code.dart
index 42aeba2..7fc4864 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix/data_driven/transform_set_error_code.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix/data_driven/transform_set_error_code.dart
@@ -156,6 +156,14 @@
   /**
    * No parameters.
    */
+  static const TransformSetErrorCode unsupportedStatic = TransformSetErrorCode(
+      'unsupported_static',
+      "The key 'static' is only supported for elements in a class, enum, "
+          "extension, or mixin.");
+
+  /**
+   * No parameters.
+   */
   static const TransformSetErrorCode unsupportedUriChange = TransformSetErrorCode(
       'unsupported_uri_change',
       "The set of URIs for the replacement element must match the transformed "
diff --git a/pkg/analysis_server/lib/src/services/correction/fix/data_driven/transform_set_parser.dart b/pkg/analysis_server/lib/src/services/correction/fix/data_driven/transform_set_parser.dart
index dc8184c..29913b3 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix/data_driven/transform_set_parser.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix/data_driven/transform_set_parser.dart
@@ -71,6 +71,7 @@
   static const String _oneOfKey = 'oneOf';
   static const String _requiredIfKey = 'requiredIf';
   static const String _setterKey = 'setter';
+  static const String _staticKey = 'static';
   static const String _styleKey = 'style';
   static const String _titleKey = 'title';
   static const String _transformsKey = 'transforms';
@@ -292,6 +293,7 @@
   /// Report any keys in the [map] whose values are not in [validKeys].
   void _reportUnsupportedKeys(YamlMap map, Set<String> validKeys) {
     for (var keyNode in map.nodes.keys) {
+      keyNode as YamlNode;
       var key = _translateKey(keyNode);
       if (key != null && !validKeys.contains(key)) {
         _reportError(TransformSetErrorCode.unsupportedKey, keyNode, [key]);
@@ -661,6 +663,8 @@
         return null;
       }
       var components = [elementName];
+      var isStatic = false;
+      var staticNode = node.valueAt(_staticKey);
       if (_containerKeyMap.containsKey(elementKey)) {
         var validContainerKeys = _containerKeyMap[elementKey]!;
         var containerKey =
@@ -683,6 +687,20 @@
         } else {
           components.add(containerName);
         }
+        if (staticNode != null) {
+          var staticValue = _translateBool(
+              staticNode, ErrorContext(key: _staticKey, parentNode: node));
+          if (staticValue != null) {
+            if (components.length == 1) {
+              _reportError(TransformSetErrorCode.unsupportedStatic,
+                  node.getKey(_staticKey)!);
+            }
+            isStatic = staticValue;
+          }
+        }
+      } else if (staticNode != null) {
+        _reportError(
+            TransformSetErrorCode.unsupportedStatic, node.getKey(_staticKey)!);
       }
       if (uris == null) {
         // The error has already been reported.
@@ -697,6 +715,7 @@
       return ElementDescriptor(
           libraryUris: uris,
           kind: ElementKindUtilities.fromName(elementKey)!,
+          isStatic: isStatic,
           components: components);
     } else if (node == null) {
       return _reportMissingKey(context);
@@ -910,7 +929,7 @@
     if (node is YamlMap) {
       var generators = <String, ValueGenerator>{};
       for (var entry in node.nodes.entries) {
-        var name = _translateKey(entry.key);
+        var name = _translateKey(entry.key as YamlNode);
         if (name != null) {
           var value = _translateValueGenerator(
               entry.value, ErrorContext(key: name, parentNode: node));
diff --git a/pkg/analysis_server/lib/src/services/correction/fix_internal.dart b/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
index 26bcfbd..0186ba9 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
@@ -25,6 +25,7 @@
 import 'package:analysis_server/src/services/correction/dart/add_override.dart';
 import 'package:analysis_server/src/services/correction/dart/add_required.dart';
 import 'package:analysis_server/src/services/correction/dart/add_required_keyword.dart';
+import 'package:analysis_server/src/services/correction/dart/add_return_null.dart';
 import 'package:analysis_server/src/services/correction/dart/add_return_type.dart';
 import 'package:analysis_server/src/services/correction/dart/add_static.dart';
 import 'package:analysis_server/src/services/correction/dart/add_super_constructor_invocation.dart';
@@ -150,6 +151,8 @@
 import 'package:analysis_server/src/services/correction/dart/replace_null_with_closure.dart';
 import 'package:analysis_server/src/services/correction/dart/replace_return_type.dart';
 import 'package:analysis_server/src/services/correction/dart/replace_return_type_future.dart';
+import 'package:analysis_server/src/services/correction/dart/replace_return_type_iterable.dart';
+import 'package:analysis_server/src/services/correction/dart/replace_return_type_stream.dart';
 import 'package:analysis_server/src/services/correction/dart/replace_var_with_dynamic.dart';
 import 'package:analysis_server/src/services/correction/dart/replace_with_brackets.dart';
 import 'package:analysis_server/src/services/correction/dart/replace_with_conditional_assignment.dart';
@@ -251,8 +254,6 @@
             workspace,
             resolveResult,
             error,
-            (name) => [],
-            extensionCache: context.extensionCache,
           );
           fixState = await _fixError(fixContext, fixState, generator(), error);
         }
@@ -311,7 +312,7 @@
 
   List<ProducerGenerator> _getGenerators(ErrorCode errorCode) {
     if (errorCode is LintCode) {
-      return FixProcessor.lintProducerMap[errorCode.name] ?? [];
+      return FixProcessor.lintProducerMap[errorCode.uniqueLintName] ?? [];
     } else {
       // todo (pq): consider support for multiGenerators
       return FixProcessor.nonLintProducerMap[errorCode] ?? [];
@@ -325,6 +326,12 @@
   /// used to create correction producers. The generators are then used to build
   /// fixes for those diagnostics. The generators used for non-lint diagnostics
   /// are in the [nonLintProducerMap].
+  ///
+  /// The keys of the map are the unique names of the lint codes without the
+  /// `LintCode.` prefix. Generally the unique name is the same as the name of
+  /// the lint, so most of the keys are constants defined by [LintNames]. But
+  /// when a lint produces multiple codes, each with a different unique name,
+  /// the unique name must be used here.
   static final Map<String, List<ProducerGenerator>> lintProducerMap = {
     LintNames.always_declare_return_types: [
       AddReturnType.newInstance,
@@ -843,9 +850,15 @@
     CompileTimeErrorCode.FINAL_NOT_INITIALIZED_CONSTRUCTOR_3_PLUS: [
       AddFieldFormalParameters.newInstance,
     ],
+    CompileTimeErrorCode.ILLEGAL_ASYNC_GENERATOR_RETURN_TYPE: [
+      ReplaceReturnTypeStream.newInstance,
+    ],
     CompileTimeErrorCode.ILLEGAL_ASYNC_RETURN_TYPE: [
       ReplaceReturnTypeFuture.newInstance,
     ],
+    CompileTimeErrorCode.ILLEGAL_SYNC_GENERATOR_RETURN_TYPE: [
+      ReplaceReturnTypeIterable.newInstance,
+    ],
     CompileTimeErrorCode.IMPLEMENTS_NON_CLASS: [
       ChangeTo.classOrMixin,
       CreateClass.newInstance,
@@ -1079,6 +1092,9 @@
       MakeReturnTypeNullable.newInstance,
     ],
 
+    HintCode.BODY_MIGHT_COMPLETE_NORMALLY_NULLABLE: [
+      AddReturnNull.newInstance,
+    ],
     HintCode.CAN_BE_NULL_AFTER_NULL_AWARE: [
       ReplaceWithNullAware.inChain,
     ],
@@ -1345,7 +1361,7 @@
 
     var errorCode = error.errorCode;
     if (errorCode is LintCode) {
-      var generators = lintProducerMap[errorCode.name] ?? [];
+      var generators = lintProducerMap[errorCode.uniqueLintName] ?? [];
       for (var generator in generators) {
         await compute(generator());
       }
@@ -1359,7 +1375,7 @@
         for (var multiGenerator in multiGenerators) {
           var multiProducer = multiGenerator();
           multiProducer.configure(context);
-          for (var producer in multiProducer.producers) {
+          await for (var producer in multiProducer.producers) {
             await compute(producer);
           }
         }
@@ -1418,3 +1434,12 @@
     required this.fixCount,
   });
 }
+
+extension on LintCode {
+  String get uniqueLintName {
+    if (uniqueName.startsWith('LintCode.')) {
+      return uniqueName.substring(9);
+    }
+    return uniqueName;
+  }
+}
diff --git a/pkg/analysis_server/lib/src/services/correction/sort_members.dart b/pkg/analysis_server/lib/src/services/correction/sort_members.dart
index 93e103a..d257984 100644
--- a/pkg/analysis_server/lib/src/services/correction/sort_members.dart
+++ b/pkg/analysis_server/lib/src/services/correction/sort_members.dart
@@ -3,9 +3,12 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:analysis_server/src/services/correction/organize_imports.dart';
+import 'package:analysis_server/src/utilities/extensions/range_factory.dart';
 import 'package:analysis_server/src/utilities/strings.dart';
 import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/source/line_info.dart';
 import 'package:analyzer_plugin/protocol/protocol_common.dart' hide Element;
+import 'package:analyzer_plugin/utilities/range_factory.dart';
 
 /// Sorter for unit/class members.
 class MemberSorter {
@@ -45,11 +48,14 @@
 
   final CompilationUnit unit;
 
+  final LineInfo lineInfo;
+
   String code;
 
   String endOfLine = '\n';
 
-  MemberSorter(this.initialCode, this.unit) : code = initialCode {
+  MemberSorter(this.initialCode, this.unit, this.lineInfo)
+      : code = initialCode {
     endOfLine = getEOL(code);
   }
 
@@ -88,15 +94,17 @@
   void _sortClassesMembers() {
     for (var unitMember in unit.declarations) {
       if (unitMember is ClassOrMixinDeclaration) {
-        _sortClassMembers(unitMember);
+        _sortClassMembers(unitMember.members);
+      } else if (unitMember is ExtensionDeclaration) {
+        _sortClassMembers(unitMember.members);
       }
     }
   }
 
   /// Sorts all members of the given [classDeclaration].
-  void _sortClassMembers(ClassOrMixinDeclaration classDeclaration) {
+  void _sortClassMembers(List<ClassMember> membersToSort) {
     var members = <_MemberInfo>[];
-    for (var member in classDeclaration.members) {
+    for (var member in membersToSort) {
       _MemberKind kind;
       var isStatic = false;
       String name;
@@ -136,8 +144,9 @@
         throw StateError('Unsupported class of member: ${member.runtimeType}');
       }
       var item = _PriorityItem.forName(isStatic, name, kind);
-      var offset = member.offset;
-      var length = member.length;
+      var nodeRange = range.nodeWithComments(lineInfo, member);
+      var offset = nodeRange.offset;
+      var length = nodeRange.length;
       var text = code.substring(offset, offset + length);
       members.add(_MemberInfo(item, name, offset, length, text));
     }
@@ -212,8 +221,9 @@
         throw StateError('Unsupported class of member: ${member.runtimeType}');
       }
       var item = _PriorityItem.forName(false, name, kind);
-      var offset = member.offset;
-      var length = member.length;
+      var nodeRange = range.nodeWithComments(lineInfo, member);
+      var offset = nodeRange.offset;
+      var length = nodeRange.length;
       var text = code.substring(offset, offset + length);
       members.add(_MemberInfo(item, name, offset, length, text));
     }
diff --git a/pkg/analysis_server/lib/src/services/correction/util.dart b/pkg/analysis_server/lib/src/services/correction/util.dart
index be7ef60..9066429 100644
--- a/pkg/analysis_server/lib/src/services/correction/util.dart
+++ b/pkg/analysis_server/lib/src/services/correction/util.dart
@@ -492,8 +492,8 @@
 }
 
 /// Return `true` if the given [lists] are identical at the given [position].
-bool _allListsIdentical(List<List> lists, int position) {
-  Object element = lists[0][position];
+bool _allListsIdentical(List<List<Object>> lists, int position) {
+  var element = lists[0][position];
   for (var list in lists) {
     if (list[position] != element) {
       return false;
diff --git a/pkg/analysis_server/lib/src/services/pub/pub_api.dart b/pkg/analysis_server/lib/src/services/pub/pub_api.dart
index d89d165..b2f9fe1 100644
--- a/pkg/analysis_server/lib/src/services/pub/pub_api.dart
+++ b/pkg/analysis_server/lib/src/services/pub/pub_api.dart
@@ -59,7 +59,7 @@
 
     final packageNames = json['packages'];
     return packageNames is List
-        ? packageNames.map((name) => PubApiPackage(name)).toList()
+        ? packageNames.map((name) => PubApiPackage(name as String)).toList()
         : null;
   }
 
@@ -103,7 +103,7 @@
             await httpClient.get(Uri.parse(url), headers: _headers);
         if (response.statusCode == 200) {
           instrumentationService.logInfo('Pub API request successful for $url');
-          return jsonDecode(response.body);
+          return jsonDecode(response.body) as Map<String, Object?>?;
         } else if (response.statusCode >= 400 && response.statusCode < 500) {
           // Do not retry 4xx responses.
           instrumentationService.logError(
diff --git a/pkg/analysis_server/lib/src/services/pub/pub_command.dart b/pkg/analysis_server/lib/src/services/pub/pub_command.dart
index f6188e0..2351441 100644
--- a/pkg/analysis_server/lib/src/services/pub/pub_command.dart
+++ b/pkg/analysis_server/lib/src/services/pub/pub_command.dart
@@ -136,7 +136,7 @@
       try {
         final results = jsonDecode(stdout);
         _instrumentationService.logInfo('pub command completed successfully');
-        return results;
+        return results as Map<String, Object?>?;
       } catch (e) {
         _instrumentationService
             .logError('pub command returned invalid JSON: $e.');
diff --git a/pkg/analysis_server/lib/src/services/pub/pub_package_service.dart b/pkg/analysis_server/lib/src/services/pub/pub_package_service.dart
index 1db29fd..db78765 100644
--- a/pkg/analysis_server/lib/src/services/pub/pub_package_service.dart
+++ b/pkg/analysis_server/lib/src/services/pub/pub_package_service.dart
@@ -322,6 +322,8 @@
       final json = jsonDecode(contents);
       if (json is Map<String, Object?>) {
         return PackageDetailsCache.fromJson(json);
+      } else {
+        return null;
       }
     } catch (e) {
       _instrumentationService.logError('Error reading pub cache file: $e');
diff --git a/pkg/analysis_server/lib/src/status/diagnostics.dart b/pkg/analysis_server/lib/src/status/diagnostics.dart
index 5ab8cff..b7f2f61 100644
--- a/pkg/analysis_server/lib/src/status/diagnostics.dart
+++ b/pkg/analysis_server/lib/src/status/diagnostics.dart
@@ -333,9 +333,8 @@
         latencyCount > 0 ? (perf.slowRequestCount / latencyCount) : 0.0;
 
     buf.write('<table>');
-    writeRow([printInteger(requestCount), 'requests'],
-        classes: ['right', null]);
-    writeRow([printInteger(latencyCount), 'requests with latency information'],
+    writeRow(['$requestCount', 'requests'], classes: ['right', null]);
+    writeRow(['$latencyCount', 'requests with latency information'],
         classes: ['right', null]);
     if (latencyCount > 0) {
       writeRow([printMilliseconds(averageLatency), 'average latency'],
@@ -431,7 +430,7 @@
                 'An analysis context defines the options and the set of sources being analyzed.');
 
   @override
-  String get navDetail => printInteger(server.driverMap.length);
+  String get navDetail => '${server.driverMap.length}';
 
   String describe(AnalysisOptionsImpl options) {
     var b = StringBuffer();
@@ -898,7 +897,7 @@
   Iterable<ServerException> get exceptions => server.exceptions.items;
 
   @override
-  String get navDetail => printInteger(exceptions.length);
+  String get navDetail => '${exceptions.length}';
 
   @override
   Future generateContent(Map<String, String> params) async {
@@ -1064,8 +1063,7 @@
     if (usage != null) {
       buf.writeln(
           writeOption('CPU', printPercentage(usage.cpuPercentage / 100.0)));
-      buf.writeln(
-          writeOption('Memory', '${printInteger(usage.memoryMB.round())} MB'));
+      buf.writeln(writeOption('Memory', '${usage.memoryMB.round()} MB'));
 
       h3('VM');
 
diff --git a/pkg/analysis_server/lib/src/status/pages.dart b/pkg/analysis_server/lib/src/status/pages.dart
index e626e02..d2c6bb3 100644
--- a/pkg/analysis_server/lib/src/status/pages.dart
+++ b/pkg/analysis_server/lib/src/status/pages.dart
@@ -5,17 +5,11 @@
 import 'dart:convert';
 import 'dart:io';
 
-import 'package:intl/intl.dart';
-
-final NumberFormat numberFormat = NumberFormat.decimalPattern();
-
 String escape(String? text) => text == null ? '' : htmlEscape.convert(text);
 
-String printInteger(int value) => numberFormat.format(value);
+String printMilliseconds(int value) => '$value ms';
 
-String printMilliseconds(num value) => '${numberFormat.format(value)} ms';
-
-String printPercentage(num value, [fractionDigits = 1]) =>
+String printPercentage(num value, [int fractionDigits = 1]) =>
     '${(value * 100).toStringAsFixed(fractionDigits)}%';
 
 /// An entity that knows how to serve itself over http.
diff --git a/pkg/analysis_server/lib/src/status/tree_writer.dart b/pkg/analysis_server/lib/src/status/tree_writer.dart
index ec20780..01543e1 100644
--- a/pkg/analysis_server/lib/src/status/tree_writer.dart
+++ b/pkg/analysis_server/lib/src/status/tree_writer.dart
@@ -80,13 +80,13 @@
 
   /// Write the [value] of the property with the given [name].
   void _writePropertyValue(Object value, int baseIndent) {
-    if (value is List) {
+    if (value is List<Object>) {
       if (value.isEmpty) {
         buffer.write('[]');
       } else {
         var elementIndent = baseIndent + 2;
         buffer.write('[<br>');
-        for (Object element in value) {
+        for (var element in value) {
           indent(elementIndent);
           _writePropertyValue(element, elementIndent);
           buffer.write('<br>');
diff --git a/pkg/analysis_server/lib/src/utilities/extensions/ast.dart b/pkg/analysis_server/lib/src/utilities/extensions/ast.dart
index 97ab036..b92d957 100644
--- a/pkg/analysis_server/lib/src/utilities/extensions/ast.dart
+++ b/pkg/analysis_server/lib/src/utilities/extensions/ast.dart
@@ -8,6 +8,18 @@
 import 'package:analyzer/dart/element/element.dart';
 
 extension AstNodeExtensions on AstNode {
+  /// Return the [IfStatement] associated with `this`.
+  IfStatement? get enclosingIfStatement {
+    for (var node in withParents) {
+      if (node is IfStatement) {
+        return node;
+      } else if (node is! Expression) {
+        return null;
+      }
+    }
+    return null;
+  }
+
   /// Return `true` if this node has an `override` annotation.
   bool get hasOverride {
     var node = this;
@@ -62,17 +74,6 @@
 
   bool get inWhileLoop => thisOrAncestorOfType<WhileStatement>() != null;
 
-  /// Return the [IfStatement] associated with `this`.
-  IfStatement? get enclosingIfStatement {
-    for (var node in withParents) {
-      if (node is IfStatement) {
-        return node;
-      } else if (node is! Expression) {
-        return null;
-      }
-    }
-  }
-
   /// Return this node and all its parents.
   Iterable<AstNode> get withParents sync* {
     var current = this;
diff --git a/pkg/analysis_server/lib/src/utilities/extensions/element.dart b/pkg/analysis_server/lib/src/utilities/extensions/element.dart
index 764d8ab..1bc51b1 100644
--- a/pkg/analysis_server/lib/src/utilities/extensions/element.dart
+++ b/pkg/analysis_server/lib/src/utilities/extensions/element.dart
@@ -2,12 +2,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
-import 'package:analyzer/dart/element/type.dart';
-import 'package:analyzer/src/dart/element/generic_inferrer.dart';
-import 'package:analyzer/src/dart/element/type_algebra.dart';
-import 'package:analyzer/src/dart/element/type_system.dart';
 
 extension ClassElementExtensions on ClassElement {
   /// Return `true` if this element represents the class `Iterable` from
@@ -60,55 +55,10 @@
   }
 }
 
-extension ExtensionElementExtensions on ExtensionElement {
-  /// Use the [type] of the object being extended in the [library] to compute
-  /// the actual type extended by this [extension]. Return the computed type,
-  /// or `null` if the type can't be computed.
-  DartType? resolvedExtendedType(LibraryElement library, DartType type) {
-    final typeParameters = this.typeParameters;
-    var inferrer =
-        GenericInferrer(library.typeSystem as TypeSystemImpl, typeParameters);
-    inferrer.constrainArgument(
-      type,
-      extendedType,
-      'extendedType',
-    );
-    var typeArguments = inferrer.infer(typeParameters,
-        failAtError: true, genericMetadataIsEnabled: true);
-    if (typeArguments == null) {
-      return null;
-    }
-    var substitution = Substitution.fromPairs(
-      typeParameters,
-      typeArguments,
-    );
-    return substitution.substituteType(
-      extendedType,
-    );
-  }
-}
-
 extension LibraryElementExtensions on LibraryElement {
-  /// Return the extensions in this library that can be applied, within the
-  /// [containingLibrary], to the [targetType] and that define a member with the
-  /// given [memberName].
-  Iterable<ExtensionElement> matchingExtensionsWithMember(
-      LibraryElement containingLibrary,
-      DartType targetType,
-      String memberName) sync* {
-    for (var unit in units) {
-      for (var extension in unit.extensions) {
-        var extensionName = extension.name;
-        if (extensionName != null && !Identifier.isPrivateName(extensionName)) {
-          var extendedType =
-              extension.resolvedExtendedType(containingLibrary, targetType);
-          if (extendedType != null &&
-              typeSystem.isSubtypeOf(targetType, extendedType)) {
-            yield extension;
-          }
-        }
-      }
-    }
+  /// Return all extensions exported from this library.
+  Iterable<ExtensionElement> get exportedExtensions {
+    return exportNamespace.definedNames.values.whereType();
   }
 }
 
diff --git a/pkg/analysis_server/lib/src/utilities/extensions/range_factory.dart b/pkg/analysis_server/lib/src/utilities/extensions/range_factory.dart
index 4b8451a..95c5384 100644
--- a/pkg/analysis_server/lib/src/utilities/extensions/range_factory.dart
+++ b/pkg/analysis_server/lib/src/utilities/extensions/range_factory.dart
@@ -9,15 +9,15 @@
 import 'package:analyzer_plugin/utilities/range_factory.dart';
 
 extension RangeFactoryExtensions on RangeFactory {
-  /// Return a source range that covers the given [item] in the containing
+  /// Return a source range that covers the given [node] in the containing
   /// [list]. This includes a leading or trailing comma, as appropriate, and any
   /// leading or trailing comments. The [lineInfo] is used to differentiate
-  /// trailing comments (on the same line as the end of the item) from leading
-  /// comments (on lines between the start of the item and the preceding comma).
+  /// trailing comments (on the same line as the end of the node) from leading
+  /// comments (on lines between the start of the node and the preceding comma).
   ///
-  /// Throws an `ArgumentError` if the [item] is not an element of the [list].
+  /// Throws an `ArgumentError` if the [node] is not an element of the [list].
   SourceRange nodeInListWithComments<T extends AstNode>(
-      LineInfo lineInfo, NodeList<T> list, T item) {
+      LineInfo lineInfo, NodeList<T> list, T node) {
     // TODO(brianwilkerson) Improve the name and signature of this method and
     //  make it part of the API of either `RangeFactory` or
     //  `DartFileEditBuilder`. The implementation currently assumes that the
@@ -28,24 +28,24 @@
     // TODO(brianwilkerson) Consider adding a `separator` parameter so that we
     //  can handle things like statements in a block.
     if (list.length == 1) {
-      if (list[0] != item) {
-        throw ArgumentError('The item must be in the list.');
+      if (list[0] != node) {
+        throw ArgumentError('The node must be in the list.');
       }
       // If there's only one item in the list, then delete everything including
       // any leading or trailing comments, including any trailing comma.
-      var leadingComment = _leadingComment(lineInfo, item.beginToken);
-      var trailingComment = _trailingComment(lineInfo, item.endToken, true);
+      var leadingComment = _leadingComment(lineInfo, node.beginToken);
+      var trailingComment = _trailingComment(lineInfo, node.endToken, true);
       return startEnd(leadingComment, trailingComment);
     }
-    final index = list.indexOf(item);
+    final index = list.indexOf(node);
     if (index < 0) {
-      throw ArgumentError('The item must be in the list.');
+      throw ArgumentError('The node must be in the list.');
     }
     if (index == 0) {
       // If this is the first item in the list, then delete everything from the
       // leading comment for this item to the leading comment for the next item.
       // This will include the comment after this item.
-      var thisLeadingComment = _leadingComment(lineInfo, item.beginToken);
+      var thisLeadingComment = _leadingComment(lineInfo, node.beginToken);
       var nextLeadingComment = _leadingComment(lineInfo, list[1].beginToken);
       return startStart(thisLeadingComment, nextLeadingComment);
     } else {
@@ -56,7 +56,7 @@
           _trailingComment(lineInfo, list[index - 1].endToken, false);
       var previousHasTrailingComment = previousTrailingComment is CommentToken;
       var thisTrailingComment =
-          _trailingComment(lineInfo, item.endToken, previousHasTrailingComment);
+          _trailingComment(lineInfo, node.endToken, previousHasTrailingComment);
       if (!previousHasTrailingComment && thisTrailingComment is CommentToken) {
         // But if this item has a trailing comment and the previous didn't, then
         // we'd be deleting both commas, which would leave invalid code. We
@@ -67,6 +67,48 @@
     }
   }
 
+  /// Return a source range that covers the given [node] with any leading and
+  /// trailing comments.
+  ///
+  /// The range begins at the start of any leading comment token (excluding any
+  /// token considered a trailing comment for the previous node) or the start
+  /// of the node itself if there are none.
+  ///
+  /// The range ends at the end of the trailing comment token or the end of the
+  /// node itself if there is not one.
+  SourceRange nodeWithComments(LineInfo lineInfo, AstNode node) {
+    // If the node is the first thing in the unit, leading comments are treated
+    // as headers and should never be included in the range.
+    final isFirstItem = node.beginToken == node.root.beginToken;
+
+    var thisLeadingComment = isFirstItem
+        ? node.beginToken
+        : _leadingComment(lineInfo, node.beginToken);
+    var thisTrailingComment = _trailingComment(lineInfo, node.endToken, false);
+
+    return startEnd(thisLeadingComment, thisTrailingComment);
+  }
+
+  /// Return the left-most comment immediately before the [token] that is not on
+  /// the same line as the first non-comment token before the [token]. Return
+  /// the [token] if there is no such comment.
+  Token _leadingComment(LineInfo lineInfo, Token token) {
+    var previous = token.previous;
+    if (previous == null || previous.type == TokenType.EOF) {
+      return token.precedingComments ?? token;
+    }
+    var previousLine = lineInfo.getLocation(previous.offset).lineNumber;
+    Token? comment = token.precedingComments;
+    while (comment != null) {
+      var commentLine = lineInfo.getLocation(comment.offset).lineNumber;
+      if (commentLine != previousLine) {
+        break;
+      }
+      comment = comment.next;
+    }
+    return comment ?? token;
+  }
+
   /// Return the comment token immediately following the [token] if it is on the
   /// same line as the [token], or the [token] if there is no comment after the
   /// [token] or if the comment is on a different line than the [token]. If
@@ -89,20 +131,4 @@
     }
     return returnComma ? lastToken : token;
   }
-
-  /// Return the left-most comment immediately before the [token] that is not on
-  /// the same line as the first non-comment token before the [token]. Return
-  /// the [token] if there is no such comment.
-  Token _leadingComment(LineInfo lineInfo, Token token) {
-    var previousLine = lineInfo.getLocation(token.previous!.offset).lineNumber;
-    Token? comment = token.precedingComments;
-    while (comment != null) {
-      var commentLine = lineInfo.getLocation(comment.offset).lineNumber;
-      if (commentLine != previousLine) {
-        break;
-      }
-      comment = comment.next;
-    }
-    return comment ?? token;
-  }
 }
diff --git a/pkg/analysis_server/lib/src/utilities/extensions/yaml.dart b/pkg/analysis_server/lib/src/utilities/extensions/yaml.dart
index 474b711..b3c0c2e 100644
--- a/pkg/analysis_server/lib/src/utilities/extensions/yaml.dart
+++ b/pkg/analysis_server/lib/src/utilities/extensions/yaml.dart
@@ -29,8 +29,9 @@
         var nextEntryOffset = i + 1 < entries.length
             ? (entries[i + 1].key as YamlNode).span.start.offset
             : null;
-        if ((entry.key as YamlNode).containsOffset(offset)) {
-          return entry.key;
+        var key = entry.key as YamlNode;
+        if (key.containsOffset(offset)) {
+          return key;
         }
         var value = entry.value;
         if (value.containsOffset(offset) ||
diff --git a/pkg/analysis_server/lib/src/utilities/flutter.dart b/pkg/analysis_server/lib/src/utilities/flutter.dart
index b733540..4cb6d42 100644
--- a/pkg/analysis_server/lib/src/utilities/flutter.dart
+++ b/pkg/analysis_server/lib/src/utilities/flutter.dart
@@ -72,64 +72,20 @@
     return null;
   }
 
-  void convertChildToChildren(
-      InstanceCreationExpression childArg,
-      NamedExpression namedExp,
-      String eol,
-      Function getNodeText,
-      Function getLinePrefix,
-      Function getIndent,
-      Function getText,
-      Function _addInsertEdit,
-      Function _addRemoveEdit,
-      Function _addReplaceEdit,
-      Function rangeNode) {
-    var childLoc = namedExp.offset + 'child'.length;
-    _addInsertEdit(childLoc, 'ren');
-    var listLoc = childArg.offset;
-    String childArgSrc = getNodeText(childArg);
-    if (!childArgSrc.contains(eol)) {
-      _addInsertEdit(listLoc, '[');
-      _addInsertEdit(listLoc + childArg.length, ']');
-    } else {
-      var newlineLoc = childArgSrc.lastIndexOf(eol);
-      if (newlineLoc == childArgSrc.length) {
-        newlineLoc -= 1;
-      }
-      String indentOld =
-          getLinePrefix(childArg.offset + eol.length + newlineLoc);
-      var indentNew = '$indentOld${getIndent(1)}';
-      // The separator includes 'child:' but that has no newlines.
-      String separator =
-          getText(namedExp.offset, childArg.offset - namedExp.offset);
-      var prefix = separator.contains(eol) ? '' : '$eol$indentNew';
-      if (prefix.isEmpty) {
-        _addInsertEdit(namedExp.offset + 'child:'.length, ' [');
-        _addRemoveEdit(SourceRange(childArg.offset - 2, 2));
-      } else {
-        _addInsertEdit(listLoc, '[');
-      }
-      var newChildArgSrc = childArgSrc.replaceAll(
-          RegExp('^$indentOld', multiLine: true), '$indentNew');
-      newChildArgSrc = '$prefix$newChildArgSrc,$eol$indentOld]';
-      _addReplaceEdit(rangeNode(childArg), newChildArgSrc);
-    }
-  }
-
   void convertChildToChildren2(
       DartFileEditBuilder builder,
       Expression childArg,
       NamedExpression namedExp,
       String eol,
-      Function getNodeText,
-      Function getLinePrefix,
-      Function getIndent,
-      Function getText,
-      Function rangeNode) {
+      String Function(Expression) getNodeText,
+      String Function(int) getLinePrefix,
+      String Function(int) getIndent,
+      String Function(int, int) getText,
+      SourceRange Function(Expression) rangeNode) {
     var childLoc = namedExp.offset + 'child'.length;
     builder.addSimpleInsertion(childLoc, 'ren');
     var listLoc = childArg.offset;
-    String childArgSrc = getNodeText(childArg);
+    var childArgSrc = getNodeText(childArg);
     if (!childArgSrc.contains(eol)) {
       builder.addSimpleInsertion(listLoc, '[');
       builder.addSimpleInsertion(listLoc + childArg.length, ']');
@@ -138,11 +94,10 @@
       if (newlineLoc == childArgSrc.length) {
         newlineLoc -= 1;
       }
-      String indentOld =
-          getLinePrefix(childArg.offset + eol.length + newlineLoc);
+      var indentOld = getLinePrefix(childArg.offset + eol.length + newlineLoc);
       var indentNew = '$indentOld${getIndent(1)}';
       // The separator includes 'child:' but that has no newlines.
-      String separator =
+      var separator =
           getText(namedExp.offset, childArg.offset - namedExp.offset);
       var prefix = separator.contains(eol) ? '' : '$eol$indentNew';
       if (prefix.isEmpty) {
diff --git a/pkg/analysis_server/lib/src/utilities/profiling.dart b/pkg/analysis_server/lib/src/utilities/profiling.dart
index b5e41fb..f1fcddb 100644
--- a/pkg/analysis_server/lib/src/utilities/profiling.dart
+++ b/pkg/analysis_server/lib/src/utilities/profiling.dart
@@ -56,7 +56,7 @@
           return Future.value(null);
         }
 
-        return Future.value(_parse(result.stdout));
+        return Future.value(_parse(result.stdout as String));
       });
     } catch (e) {
       return Future.error(e);
diff --git a/pkg/analysis_server/lib/src/utilities/progress.dart b/pkg/analysis_server/lib/src/utilities/progress.dart
new file mode 100644
index 0000000..822b750
--- /dev/null
+++ b/pkg/analysis_server/lib/src/utilities/progress.dart
@@ -0,0 +1,25 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+class CancelableToken extends CancellationToken {
+  bool _isCancelled = false;
+
+  @override
+  bool get isCancellationRequested => _isCancelled;
+
+  void cancel() => _isCancelled = true;
+}
+
+/// A token used to signal cancellation of an operation. This allows computation
+/// to be skipped when a caller is no longer interested in the result, for example
+/// when a $/cancel request is recieved for an in-progress request.
+abstract class CancellationToken {
+  bool get isCancellationRequested;
+}
+
+/// A [CancellationToken] that cannot be cancelled.
+class NotCancelableToken extends CancellationToken {
+  @override
+  bool get isCancellationRequested => false;
+}
diff --git a/pkg/analysis_server/lib/src/utilities/yaml_node_locator.dart b/pkg/analysis_server/lib/src/utilities/yaml_node_locator.dart
index c8c49ef..c04e29e 100644
--- a/pkg/analysis_server/lib/src/utilities/yaml_node_locator.dart
+++ b/pkg/analysis_server/lib/src/utilities/yaml_node_locator.dart
@@ -49,7 +49,7 @@
     } else if (node is YamlMap) {
       var nodeMap = node.nodes;
       for (var entry in nodeMap.entries) {
-        _searchWithin(path, entry.key);
+        _searchWithin(path, entry.key as YamlNode);
         if (path.isNotEmpty) {
           path.add(node);
           return;
diff --git a/pkg/analysis_server/pubspec.yaml b/pkg/analysis_server/pubspec.yaml
index bb60379..39518e8 100644
--- a/pkg/analysis_server/pubspec.yaml
+++ b/pkg/analysis_server/pubspec.yaml
@@ -20,7 +20,6 @@
   dart_style: any
   http: any
   html: any
-  intl: any
   linter: any
   meta:
     path: ../meta
diff --git a/pkg/analysis_server/test/abstract_context.dart b/pkg/analysis_server/test/abstract_context.dart
index 09fdeee..432a8b3 100644
--- a/pkg/analysis_server/test/abstract_context.dart
+++ b/pkg/analysis_server/test/abstract_context.dart
@@ -56,6 +56,9 @@
       '${ExperimentStatus.currentVersion.major}.'
       '${ExperimentStatus.currentVersion.minor}';
 
+  /// The path that is not in [workspaceRootPath], contains external packages.
+  String get packagesRootPath => '/packages';
+
   Folder get sdkRoot => newFolder('/sdk');
 
   AnalysisSession get session => contextFor('/home/test').currentSession;
@@ -66,6 +69,8 @@
 
   String get testPackageRootPath => '$workspaceRootPath/test';
 
+  String get testPackageTestPath => '$testPackageRootPath/test';
+
   /// The file system specific `/home/test/pubspec.yaml` path.
   String get testPubspecPath => convertPath('/home/test/pubspec.yaml');
 
diff --git a/pkg/analysis_server/test/abstract_single_unit.dart b/pkg/analysis_server/test/abstract_single_unit.dart
index 67aa683..0c09690 100644
--- a/pkg/analysis_server/test/abstract_single_unit.dart
+++ b/pkg/analysis_server/test/abstract_single_unit.dart
@@ -64,13 +64,8 @@
     return super.newFile(path, content: content);
   }
 
-  Future<void> resolveTestCode(String code) async {
-    addTestSource(code);
-    await resolveTestFile();
-  }
-
-  Future<void> resolveTestFile() async {
-    var result = await session.getResolvedUnit(testFile) as ResolvedUnitResult;
+  Future<void> resolveFile2(String path) async {
+    var result = await session.getResolvedUnit(path) as ResolvedUnitResult;
     testAnalysisResult = result;
     testCode = result.content;
     testUnit = result.unit;
@@ -91,6 +86,15 @@
     findElement = FindElement(testUnit);
   }
 
+  Future<void> resolveTestCode(String code) async {
+    addTestSource(code);
+    await resolveTestFile();
+  }
+
+  Future<void> resolveTestFile() async {
+    await resolveFile2(testFile);
+  }
+
   @override
   void setUp() {
     super.setUp();
diff --git a/pkg/analysis_server/test/analysis_abstract.dart b/pkg/analysis_server/test/analysis_abstract.dart
index 809d27a..558a318 100644
--- a/pkg/analysis_server/test/analysis_abstract.dart
+++ b/pkg/analysis_server/test/analysis_abstract.dart
@@ -10,6 +10,7 @@
 import 'package:analysis_server/src/domain_analysis.dart';
 import 'package:analysis_server/src/server/crash_reporting_attachments.dart';
 import 'package:analysis_server/src/utilities/mocks.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/instrumentation/instrumentation.dart';
 import 'package:analyzer/src/dart/analysis/driver.dart';
 import 'package:analyzer/src/generated/engine.dart';
@@ -145,7 +146,7 @@
   /// Validates that the given [request] is handled successfully.
   Response handleSuccessfulRequest(Request request, {RequestHandler? handler}) {
     handler ??= this.handler;
-    var response = handler.handleRequest(request)!;
+    var response = handler.handleRequest(request, NotCancelableToken())!;
     expect(response, isResponseSuccess(request.id));
     return response;
   }
diff --git a/pkg/analysis_server/test/analysis_server_test.dart b/pkg/analysis_server/test/analysis_server_test.dart
index 4b41a22..907c39a 100644
--- a/pkg/analysis_server/test/analysis_server_test.dart
+++ b/pkg/analysis_server/test/analysis_server_test.dart
@@ -9,6 +9,7 @@
 import 'package:analysis_server/src/domain_server.dart';
 import 'package:analysis_server/src/server/crash_reporting_attachments.dart';
 import 'package:analysis_server/src/utilities/mocks.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/instrumentation/instrumentation.dart';
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/test_utilities/mock_sdk.dart';
@@ -94,7 +95,7 @@
   }
 
   Future test_echo() {
-    server.handlers = [EchoHandler()];
+    server.handlers = [EchoHandler(server)];
     var request = Request('my22', 'echo');
     return channel.sendRequest(request).then((Response response) {
       expect(response.id, equals('my22'));
@@ -215,8 +216,39 @@
     });
   }
 
+  Future test_slowEcho_cancelled() async {
+    server.handlers = [
+      ServerDomainHandler(server),
+      EchoHandler(server),
+    ];
+    // Send the normal request.
+    var responseFuture = channel.sendRequest(Request('my22', 'slowEcho'));
+    // Send a cancellation for it for waiting for it to complete.
+    channel.sendRequest(
+      Request(
+        'my23',
+        'server.cancelRequest',
+        {'id': 'my22'},
+      ),
+    );
+    var response = await responseFuture;
+    expect(response.id, equals('my22'));
+    expect(response.error, isNull);
+    expect(response.result!['cancelled'], isTrue);
+  }
+
+  Future test_slowEcho_notCancelled() {
+    server.handlers = [EchoHandler(server)];
+    var request = Request('my22', 'slowEcho');
+    return channel.sendRequest(request).then((Response response) {
+      expect(response.id, equals('my22'));
+      expect(response.error, isNull);
+      expect(response.result!['cancelled'], isFalse);
+    });
+  }
+
   Future test_unknownRequest() {
-    server.handlers = [EchoHandler()];
+    server.handlers = [EchoHandler(server)];
     var request = Request('my22', 'randomRequest');
     return channel.sendRequest(request).then((Response response) {
       expect(response.id, equals('my22'));
@@ -226,11 +258,29 @@
 }
 
 class EchoHandler implements RequestHandler {
+  final AnalysisServer server;
+
+  EchoHandler(this.server);
+
   @override
-  Response? handleRequest(Request request) {
+  Response? handleRequest(
+      Request request, CancellationToken cancellationToken) {
     if (request.method == 'echo') {
       return Response(request.id, result: {'echo': true});
+    } else if (request.method == 'slowEcho') {
+      _slowEcho(request, cancellationToken);
+      return Response.DELAYED_RESPONSE;
     }
     return null;
   }
+
+  void _slowEcho(Request request, CancellationToken cancellationToken) async {
+    for (var i = 0; i < 100; i++) {
+      if (cancellationToken.isCancellationRequested) {
+        server.sendResponse(Response(request.id, result: {'cancelled': true}));
+      }
+      await Future.delayed(const Duration(milliseconds: 10));
+    }
+    server.sendResponse(Response(request.id, result: {'cancelled': false}));
+  }
 }
diff --git a/pkg/analysis_server/test/benchmarks_test.dart b/pkg/analysis_server/test/benchmarks_test.dart
index 87a822e..30e5da63 100644
--- a/pkg/analysis_server/test/benchmarks_test.dart
+++ b/pkg/analysis_server/test/benchmarks_test.dart
@@ -61,7 +61,7 @@
     [path.join('benchmark', 'benchmarks.dart'), 'list', '--machine'],
     workingDirectory: _serverSourcePath,
   );
-  Map m = json.decode(result.stdout);
-  List benchmarks = m['benchmarks'];
+  var output = json.decode(result.stdout as String) as Map<Object?, Object?>;
+  var benchmarks = (output['benchmarks'] as List).cast<Map<Object?, Object?>>();
   return benchmarks.map((b) => b['id']).cast<String>().toList();
 }
diff --git a/pkg/analysis_server/test/client/impl/abstract_client.dart b/pkg/analysis_server/test/client/impl/abstract_client.dart
index 51bd14d..999451f 100644
--- a/pkg/analysis_server/test/client/impl/abstract_client.dart
+++ b/pkg/analysis_server/test/client/impl/abstract_client.dart
@@ -10,6 +10,7 @@
 import 'package:analysis_server/src/domain_completion.dart';
 import 'package:analysis_server/src/server/crash_reporting_attachments.dart';
 import 'package:analysis_server/src/utilities/mocks.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer/instrumentation/instrumentation.dart';
@@ -132,7 +133,7 @@
   /// Validate that the given [request] is handled successfully.
   Response handleSuccessfulRequest(Request request, {RequestHandler? handler}) {
     handler ??= analysisHandler;
-    var response = handler.handleRequest(request)!;
+    var response = handler.handleRequest(request, NotCancelableToken())!;
     expect(response, isResponseSuccess(request.id));
     return response;
   }
diff --git a/pkg/analysis_server/test/client/impl/expect_mixin.dart b/pkg/analysis_server/test/client/impl/expect_mixin.dart
index 7f75f64..67cdc1c 100644
--- a/pkg/analysis_server/test/client/impl/expect_mixin.dart
+++ b/pkg/analysis_server/test/client/impl/expect_mixin.dart
@@ -30,7 +30,7 @@
     } else if (x is _Predicate<Null>) {
       // x is a unary predicate, but expects a specific type
       // so wrap it.
-      return predicate((a) => (x as dynamic)(a));
+      return predicate((a) => (x as dynamic)(a) as bool);
     } else {
       return equals(x);
     }
diff --git a/pkg/analysis_server/test/domain_analysis_test.dart b/pkg/analysis_server/test/domain_analysis_test.dart
index 317cc59..fa3b3e4 100644
--- a/pkg/analysis_server/test/domain_analysis_test.dart
+++ b/pkg/analysis_server/test/domain_analysis_test.dart
@@ -11,6 +11,7 @@
 import 'package:analysis_server/src/domain_analysis.dart';
 import 'package:analysis_server/src/server/crash_reporting_attachments.dart';
 import 'package:analysis_server/src/utilities/mocks.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/instrumentation/instrumentation.dart';
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/test_utilities/mock_sdk.dart';
@@ -89,7 +90,7 @@
     var contentChange = ChangeContentOverlay([edit]);
     var request = AnalysisUpdateContentParams({helper.testFile: contentChange})
         .toRequest('0');
-    var response = helper.handler.handleRequest(request);
+    var response = helper.handler.handleRequest(request, NotCancelableToken());
     expect(response,
         isResponseFailure('0', RequestErrorCode.INVALID_OVERLAY_CHANGE));
   }
@@ -156,7 +157,7 @@
     var request = AnalysisSetPriorityFilesParams(
       [convertPath('/project/lib.dart')],
     ).toRequest('0');
-    var response = handler.handleRequest(request);
+    var response = handler.handleRequest(request, NotCancelableToken());
     expect(response, isResponseSuccess('0'));
   }
 
@@ -172,12 +173,13 @@
 
     var setRootsRequest =
         AnalysisSetAnalysisRootsParams([p1, p2], []).toRequest('0');
-    var setRootsResponse = handler.handleRequest(setRootsRequest);
+    var setRootsResponse =
+        handler.handleRequest(setRootsRequest, NotCancelableToken());
     expect(setRootsResponse, isResponseSuccess('0'));
 
     void setPriorityFiles(List<String> fileList) {
       var request = AnalysisSetPriorityFilesParams(fileList).toRequest('0');
-      var response = handler.handleRequest(request);
+      var response = handler.handleRequest(request, NotCancelableToken());
       expect(response, isResponseSuccess('0'));
       // TODO(brianwilkerson) Enable the line below after getPriorityFiles
       // has been implemented.
@@ -200,7 +202,7 @@
         }
       }
     });
-    var response = helper.handler.handleRequest(request);
+    var response = helper.handler.handleRequest(request, NotCancelableToken());
     expect(response, isResponseFailure('0'));
   }
 
@@ -290,7 +292,7 @@
     var request = Request('0', ANALYSIS_REQUEST_UPDATE_OPTIONS, {
       ANALYSIS_REQUEST_UPDATE_OPTIONS_OPTIONS: {'not-an-option': true}
     });
-    var response = handler.handleRequest(request);
+    var response = handler.handleRequest(request, NotCancelableToken());
     // Invalid options should be silently ignored.
     expect(response, isResponseSuccess('0'));
   }
@@ -299,14 +301,14 @@
     // null is allowed as a synonym for {}.
     var request = Request('0', ANALYSIS_REQUEST_UPDATE_OPTIONS,
         {ANALYSIS_REQUEST_UPDATE_OPTIONS_OPTIONS: null});
-    var response = handler.handleRequest(request);
+    var response = handler.handleRequest(request, NotCancelableToken());
     expect(response, isResponseSuccess('0'));
   }
 
   Response testSetAnalysisRoots(List<String> included, List<String> excluded) {
     var request =
         AnalysisSetAnalysisRootsParams(included, excluded).toRequest('0');
-    return handler.handleRequest(request)!;
+    return handler.handleRequest(request, NotCancelableToken())!;
   }
 
   Future<void> xtest_getReachableSources_invalidSource() async {
@@ -319,7 +321,7 @@
 
     var request = AnalysisGetReachableSourcesParams('/does/not/exist.dart')
         .toRequest('0');
-    var response = handler.handleRequest(request)!;
+    var response = handler.handleRequest(request, NotCancelableToken())!;
     var error = response.error!;
     expect(error.code, RequestErrorCode.GET_REACHABLE_SOURCES_INVALID_FILE);
   }
@@ -335,7 +337,7 @@
     await server.onAnalysisComplete;
 
     var request = AnalysisGetReachableSourcesParams(fileA).toRequest('0');
-    var response = handler.handleRequest(request)!;
+    var response = handler.handleRequest(request, NotCancelableToken())!;
 
     var json = response.toJson()[Response.RESULT] as Map<String, dynamic>;
 
@@ -1577,7 +1579,7 @@
 
   /// Validates that the given [request] is handled successfully.
   void handleSuccessfulRequest(Request request) {
-    var response = handler.handleRequest(request);
+    var response = handler.handleRequest(request, NotCancelableToken());
     expect(response, isResponseSuccess('0'));
   }
 
diff --git a/pkg/analysis_server/test/domain_completion_test.dart b/pkg/analysis_server/test/domain_completion_test.dart
index c3ec9c3..e3a94a0 100644
--- a/pkg/analysis_server/test/domain_completion_test.dart
+++ b/pkg/analysis_server/test/domain_completion_test.dart
@@ -2783,18 +2783,18 @@
 
 extension on CheckTarget<CompletionGetSuggestionDetails2Result> {
   @useResult
-  CheckTarget<String> get completion {
-    return nest(
-      value.completion,
-      (selected) => 'has completion ${valueStr(selected)}',
-    );
-  }
-
-  @useResult
   CheckTarget<SourceChange> get change {
     return nest(
       value.change,
       (selected) => 'has change ${valueStr(selected)}',
     );
   }
+
+  @useResult
+  CheckTarget<String> get completion {
+    return nest(
+      value.completion,
+      (selected) => 'has completion ${valueStr(selected)}',
+    );
+  }
 }
diff --git a/pkg/analysis_server/test/domain_diagnostic_test.dart b/pkg/analysis_server/test/domain_diagnostic_test.dart
index f83771a..92ab990 100644
--- a/pkg/analysis_server/test/domain_diagnostic_test.dart
+++ b/pkg/analysis_server/test/domain_diagnostic_test.dart
@@ -4,6 +4,7 @@
 
 import 'package:analysis_server/protocol/protocol_generated.dart';
 import 'package:analysis_server/src/domain_diagnostic.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
@@ -33,7 +34,7 @@
     await server.onAnalysisComplete;
 
     var request = DiagnosticGetDiagnosticsParams().toRequest('0');
-    var response = handler.handleRequest(request)!;
+    var response = handler.handleRequest(request, NotCancelableToken())!;
     var result = DiagnosticGetDiagnosticsResult.fromResponse(response);
 
     expect(result.contexts, hasLength(1));
@@ -49,7 +50,7 @@
 
   Future<void> test_getDiagnostics_noRoot() async {
     var request = DiagnosticGetDiagnosticsParams().toRequest('0');
-    var response = handler.handleRequest(request)!;
+    var response = handler.handleRequest(request, NotCancelableToken())!;
     var result = DiagnosticGetDiagnosticsResult.fromResponse(response);
     expect(result.contexts, isEmpty);
   }
diff --git a/pkg/analysis_server/test/domain_execution_test.dart b/pkg/analysis_server/test/domain_execution_test.dart
index 107cab5..7095b0c 100644
--- a/pkg/analysis_server/test/domain_execution_test.dart
+++ b/pkg/analysis_server/test/domain_execution_test.dart
@@ -8,6 +8,7 @@
 import 'package:analysis_server/src/protocol_server.dart';
 import 'package:analysis_server/src/server/crash_reporting_attachments.dart';
 import 'package:analysis_server/src/utilities/mocks.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer/instrumentation/instrumentation.dart';
 import 'package:analyzer/src/generated/sdk.dart';
@@ -40,13 +41,13 @@
     group('createContext/deleteContext', () {
       test('create/delete multiple contexts', () {
         var request = ExecutionCreateContextParams('/a/b.dart').toRequest('0');
-        var response = handler.handleRequest(request)!;
+        var response = handler.handleRequest(request, NotCancelableToken())!;
         expect(response, isResponseSuccess('0'));
         var result = ExecutionCreateContextResult.fromResponse(response);
         var id0 = result.id;
 
         request = ExecutionCreateContextParams('/c/d.dart').toRequest('1');
-        response = handler.handleRequest(request)!;
+        response = handler.handleRequest(request, NotCancelableToken())!;
         expect(response, isResponseSuccess('1'));
         result = ExecutionCreateContextResult.fromResponse(response);
         var id1 = result.id;
@@ -54,17 +55,17 @@
         expect(id0 == id1, isFalse);
 
         request = ExecutionDeleteContextParams(id0).toRequest('2');
-        response = handler.handleRequest(request)!;
+        response = handler.handleRequest(request, NotCancelableToken())!;
         expect(response, isResponseSuccess('2'));
 
         request = ExecutionDeleteContextParams(id1).toRequest('3');
-        response = handler.handleRequest(request)!;
+        response = handler.handleRequest(request, NotCancelableToken())!;
         expect(response, isResponseSuccess('3'));
       });
 
       test('delete non-existent context', () {
         var request = ExecutionDeleteContextParams('13').toRequest('0');
-        var response = handler.handleRequest(request);
+        var response = handler.handleRequest(request, NotCancelableToken());
         // TODO(brianwilkerson) It isn't currently specified to be an error if a
         // client attempts to delete a context that doesn't exist. Should it be?
 //        expect(response, isResponseFailure('0'));
@@ -79,7 +80,7 @@
 //
 //      void createExecutionContextIdForFile(String path) {
 //        Request request = new ExecutionCreateContextParams(path).toRequest('0');
-//        Response response = handler.handleRequest(request);
+//        Response response = handler.handleRequest(request, NotCancelableToken());
 //        expect(response, isResponseSuccess('0'));
 //        ExecutionCreateContextResult result =
 //            new ExecutionCreateContextResult.fromResponse(response);
@@ -102,7 +103,7 @@
 //      tearDown(() {
 //        Request request =
 //            new ExecutionDeleteContextParams(contextId).toRequest('1');
-//        Response response = handler.handleRequest(request);
+//        Response response = handler.handleRequest(request, NotCancelableToken());
 //        expect(response, isResponseSuccess('1'));
 //      });
 //
@@ -111,7 +112,7 @@
 //          Request request =
 //              new ExecutionMapUriParams(contextId, file: '/a/c.dart')
 //                  .toRequest('2');
-//          Response response = handler.handleRequest(request);
+//          Response response = handler.handleRequest(request, NotCancelableToken());
 //          expect(response, isResponseFailure('2'));
 //        });
 //
@@ -119,7 +120,7 @@
 //          provider.newFolder('/a/d');
 //          Request request =
 //              new ExecutionMapUriParams(contextId, file: '/a/d').toRequest('2');
-//          Response response = handler.handleRequest(request);
+//          Response response = handler.handleRequest(request, NotCancelableToken());
 //          expect(response, isResponseFailure('2'));
 //        });
 //      });
@@ -129,7 +130,7 @@
 //          Request request =
 //              new ExecutionMapUriParams(contextId, uri: 'foo:///a/b.dart')
 //                  .toRequest('2');
-//          Response response = handler.handleRequest(request);
+//          Response response = handler.handleRequest(request, NotCancelableToken());
 //          expect(response, isResponseFailure('2'));
 //        });
 //      });
@@ -137,20 +138,20 @@
 //      test('invalid context id', () {
 //        Request request =
 //            new ExecutionMapUriParams('xxx', uri: '').toRequest('4');
-//        Response response = handler.handleRequest(request);
+//        Response response = handler.handleRequest(request, NotCancelableToken());
 //        expect(response, isResponseFailure('4'));
 //      });
 //
 //      test('both file and uri', () {
 //        Request request =
 //            new ExecutionMapUriParams('xxx', file: '', uri: '').toRequest('5');
-//        Response response = handler.handleRequest(request);
+//        Response response = handler.handleRequest(request, NotCancelableToken());
 //        expect(response, isResponseFailure('5'));
 //      });
 //
 //      test('neither file nor uri', () {
 //        Request request = new ExecutionMapUriParams('xxx').toRequest('6');
-//        Response response = handler.handleRequest(request);
+//        Response response = handler.handleRequest(request, NotCancelableToken());
 //        expect(response, isResponseFailure('6'));
 //      });
 //    });
@@ -237,7 +238,7 @@
 
   void _createExecutionContext(String path) {
     var request = ExecutionCreateContextParams(path).toRequest('0');
-    var response = handler.handleRequest(request)!;
+    var response = handler.handleRequest(request, NotCancelableToken())!;
     expect(response, isResponseSuccess('0'));
     var result = ExecutionCreateContextResult.fromResponse(response);
     contextId = result.id;
@@ -245,14 +246,14 @@
 
   void _disposeExecutionContext() {
     var request = ExecutionDeleteContextParams(contextId).toRequest('1');
-    var response = handler.handleRequest(request);
+    var response = handler.handleRequest(request, NotCancelableToken());
     expect(response, isResponseSuccess('1'));
   }
 
   ExecutionMapUriResult _mapUri({String? file, String? uri}) {
     var request =
         ExecutionMapUriParams(contextId, file: file, uri: uri).toRequest('2');
-    var response = handler.handleRequest(request)!;
+    var response = handler.handleRequest(request, NotCancelableToken())!;
     expect(response, isResponseSuccess('2'));
     return ExecutionMapUriResult.fromResponse(response);
   }
diff --git a/pkg/analysis_server/test/domain_server_test.dart b/pkg/analysis_server/test/domain_server_test.dart
index 2202712..b7bfaa8 100644
--- a/pkg/analysis_server/test/domain_server_test.dart
+++ b/pkg/analysis_server/test/domain_server_test.dart
@@ -9,6 +9,7 @@
 import 'package:analysis_server/src/domain_server.dart';
 import 'package:analysis_server/src/server/crash_reporting_attachments.dart';
 import 'package:analysis_server/src/utilities/mocks.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer/instrumentation/instrumentation.dart';
 import 'package:analyzer/src/generated/sdk.dart';
@@ -38,7 +39,7 @@
   group('ServerDomainHandler', () {
     test('getVersion', () {
       var request = ServerGetVersionParams().toRequest('0');
-      var response = handler.handleRequest(request)!;
+      var response = handler.handleRequest(request, NotCancelableToken())!;
       expect(
           response.toJson(),
           equals({
@@ -52,7 +53,7 @@
         var request = Request('0', SERVER_REQUEST_SET_SUBSCRIPTIONS, {
           SUBSCRIPTIONS: ['noSuchService']
         });
-        var response = handler.handleRequest(request);
+        var response = handler.handleRequest(request, NotCancelableToken());
         expect(response, isResponseFailure('0'));
       });
 
@@ -61,7 +62,7 @@
         // send request
         var request =
             ServerSetSubscriptionsParams([ServerService.STATUS]).toRequest('0');
-        var response = handler.handleRequest(request);
+        var response = handler.handleRequest(request, NotCancelableToken());
         expect(response, isResponseSuccess('0'));
         // set of services has been changed
         expect(server.serverServices, contains(ServerService.STATUS));
diff --git a/pkg/analysis_server/test/edit/format_test.dart b/pkg/analysis_server/test/edit/format_test.dart
index 1990b31..e5576f7 100644
--- a/pkg/analysis_server/test/edit/format_test.dart
+++ b/pkg/analysis_server/test/edit/format_test.dart
@@ -4,6 +4,7 @@
 
 import 'package:analysis_server/protocol/protocol_generated.dart';
 import 'package:analysis_server/src/edit/edit_domain.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
@@ -104,7 +105,7 @@
 ''');
     return waitForTasksFinished().then((_) {
       var request = EditFormatParams(testFile, 0, 3).toRequest('0');
-      var response = handler.handleRequest(request);
+      var response = handler.handleRequest(request, NotCancelableToken());
       expect(response, isResponseFailure('0'));
     });
   }
diff --git a/pkg/analysis_server/test/edit/postfix_completion_test.dart b/pkg/analysis_server/test/edit/postfix_completion_test.dart
index e58ee6c..86085b1 100644
--- a/pkg/analysis_server/test/edit/postfix_completion_test.dart
+++ b/pkg/analysis_server/test/edit/postfix_completion_test.dart
@@ -67,21 +67,12 @@
     );
   }
 
-  void _assertHasChange(String message, String expectedCode, [Function? cmp]) {
+  void _assertHasChange(String message, String expectedCode) {
     if (change.message == message) {
       if (change.edits.isNotEmpty) {
         var resultCode =
             SourceEdit.applySequence(testCode, change.edits[0].edits);
         expect(resultCode, expectedCode.replaceAll('/*caret*/', ''));
-        if (cmp != null) {
-          int offset = cmp(resultCode);
-          expect(change.selection!.offset, offset);
-        }
-      } else {
-        if (cmp != null) {
-          int offset = cmp(testCode);
-          expect(change.selection!.offset, offset);
-        }
       }
       return;
     }
diff --git a/pkg/analysis_server/test/edit/statement_completion_test.dart b/pkg/analysis_server/test/edit/statement_completion_test.dart
index 09e11a7..a692a0f 100644
--- a/pkg/analysis_server/test/edit/statement_completion_test.dart
+++ b/pkg/analysis_server/test/edit/statement_completion_test.dart
@@ -101,19 +101,20 @@
         (s) => s.indexOf(match) + match.length); // Ensure cursor after '='.
   }
 
-  void _assertHasChange(String message, String expectedCode, [Function? cmp]) {
+  void _assertHasChange(String message, String expectedCode,
+      [int Function(String)? cmp]) {
     if (change.message == message) {
       if (change.edits.isNotEmpty) {
         var resultCode =
             SourceEdit.applySequence(testCode, change.edits[0].edits);
         expect(resultCode, expectedCode.replaceAll('/*caret*/', ''));
         if (cmp != null) {
-          int offset = cmp(resultCode);
+          var offset = cmp(resultCode);
           expect(change.selection!.offset, offset);
         }
       } else {
         if (cmp != null) {
-          int offset = cmp(testCode);
+          var offset = cmp(testCode);
           expect(change.selection!.offset, offset);
         }
       }
diff --git a/pkg/analysis_server/test/integration/coverage.md b/pkg/analysis_server/test/integration/coverage.md
index b91da0a..9cd7a76 100644
--- a/pkg/analysis_server/test/integration/coverage.md
+++ b/pkg/analysis_server/test/integration/coverage.md
@@ -84,6 +84,7 @@
 - [ ] server.error
 - [ ] server.log
 - [x] server.status
+- [ ] server.cancelRequest
 
 ## analytics domain
 - [x] analytics.isEnabled
diff --git a/pkg/analysis_server/test/integration/support/integration_test_methods.dart b/pkg/analysis_server/test/integration/support/integration_test_methods.dart
index aa0d470..b8704aa 100644
--- a/pkg/analysis_server/test/integration/support/integration_test_methods.dart
+++ b/pkg/analysis_server/test/integration/support/integration_test_methods.dart
@@ -64,6 +64,26 @@
     return null;
   }
 
+  /// Requests cancellation of a request sent by the client by id. This is
+  /// provided on a best-effort basis and there is no guarantee the server will
+  /// be able to cancel any specific request. The server will still always
+  /// produce a response to the request even in the case of cancellation, but
+  /// clients should discard any results of any cancelled request because they
+  /// may be incomplete or inaccurate. This request always completes without
+  /// error regardless of whether the request is successfully cancelled.
+  ///
+  /// Parameters
+  ///
+  /// id: String
+  ///
+  ///   The id of the request that should be cancelled.
+  Future sendServerCancelRequest(String id) async {
+    var params = ServerCancelRequestParams(id).toJson();
+    var result = await server.send('server.cancelRequest', params);
+    outOfTestExpect(result, isNull);
+    return null;
+  }
+
   /// Reports that the server is running. This notification is issued once
   /// after the server has started running but before any requests are
   /// processed to let the client know that it started correctly.
diff --git a/pkg/analysis_server/test/integration/support/protocol_matchers.dart b/pkg/analysis_server/test/integration/support/protocol_matchers.dart
index 70848d4..a7e358db 100644
--- a/pkg/analysis_server/test/integration/support/protocol_matchers.dart
+++ b/pkg/analysis_server/test/integration/support/protocol_matchers.dart
@@ -3014,6 +3014,17 @@
     'search.results params',
     {'id': isSearchId, 'results': isListOf(isSearchResult), 'isLast': isBool}));
 
+/// server.cancelRequest params
+///
+/// {
+///   "id": String
+/// }
+final Matcher isServerCancelRequestParams = LazyMatcher(
+    () => MatchesJsonObject('server.cancelRequest params', {'id': isString}));
+
+/// server.cancelRequest result
+final Matcher isServerCancelRequestResult = isNull;
+
 /// server.connected params
 ///
 /// {
diff --git a/pkg/analysis_server/test/lsp/initialization_test.dart b/pkg/analysis_server/test/lsp/initialization_test.dart
index 4d006be..413afeb 100644
--- a/pkg/analysis_server/test/lsp/initialization_test.dart
+++ b/pkg/analysis_server/test/lsp/initialization_test.dart
@@ -136,6 +136,94 @@
     );
   }
 
+  Future<void> test_dynamicRegistration_areNotInterleaved() async {
+    // Some of the issues in https://github.com/dart-lang/sdk/issues/47851
+    // (duplicate hovers/code actions/etc.) were caused by duplicate
+    // registrations. This happened when we tried to rebuild registrations
+    // concurrently as the code would:
+    //
+    // 1. compute the new set of registrations
+    // 2. compute which had changed
+    // 3. send _and await_ the unregistration
+    // 4. send _and await_ the new registration
+    //
+    // If the code was triggered multiple times concurrently, it was possible
+    // for step 3 in second request to occur before step 4 in the first, which
+    // would result in unregistrations being sent for registrations that had
+    // not been sent. They would be silently dropped, and then we'd end up with
+    // multiple registrations.
+    //
+    // This test triggers the rebuild via pluginManager.pluginsChangedController
+    // multiple times and ensures the events all arrive in the correct order,
+    // that is, no unregistration ever contains the ID of something that is not
+    // currently registered.
+
+    final registrations = <Registration>[];
+    await monitorDynamicRegistrations(
+      registrations,
+      () => initialize(
+          textDocumentCapabilities:
+              withAllSupportedTextDocumentDynamicRegistrations(
+                  emptyTextDocumentClientCapabilities)),
+    );
+
+    final knownRegistrationsIds =
+        registrations.map((registration) => registration.id).toSet();
+
+    final numberOfReregistrations = 10;
+
+    // Listen to incoming registrations, ensure they're not in the set, and add
+    // them.
+    final registrationsDone = requestsFromServer
+        .where((n) => n.method == Method.client_registerCapability)
+        .take(numberOfReregistrations)
+        .listen((request) {
+      respondTo(request, null);
+      final registrations =
+          RegistrationParams.fromJson(request.params as Map<String, Object?>)
+              .registrations;
+      for (final registration in registrations) {
+        final id = registration.id;
+        if (!knownRegistrationsIds.add(id)) {
+          throw 'Registration $id was already in the existing set!';
+        }
+      }
+    }).asFuture();
+
+    // Listen to incoming unregistrations, verify they're in the set, and remove
+    // them.
+    final unregistrationsDone = requestsFromServer
+        .where((n) => n.method == Method.client_unregisterCapability)
+        .take(numberOfReregistrations)
+        .listen((request) {
+      respondTo(request, null);
+      final unregistrations =
+          UnregistrationParams.fromJson(request.params as Map<String, Object?>)
+              .unregisterations;
+      for (final unregistration in unregistrations) {
+        final id = unregistration.id;
+        if (!knownRegistrationsIds.remove(id)) {
+          throw 'Registration $id was not in the existing set!';
+        }
+      }
+    }).asFuture();
+
+    // Trigger multiple plugin events that will rebuild the registrations.
+    for (var i = 0; i < numberOfReregistrations; i++) {
+      final plugin = configureTestPlugin();
+      plugin.currentSession = PluginSession(plugin);
+      // Ensure they have different file types so the registrations change,
+      // otherwise they will be optimised out as not changing.
+      plugin.currentSession!.interestingFiles = ['*.foo$i'];
+      pluginManager.pluginsChangedController.add(null);
+      await null; // Allow the server to begin processing the change.
+    }
+
+    // Wait for both streams to have handled all of the numberOfReregistrations
+    // expected events (without throwing).
+    await Future.wait([registrationsDone, unregistrationsDone]);
+  }
+
   Future<void> test_dynamicRegistration_containsAppropriateSettings() async {
     // Basic check that the server responds with the capabilities we'd expect,
     // for ex including analysis_options.yaml in text synchronization but not
diff --git a/pkg/analysis_server/test/lsp/signature_help_test.dart b/pkg/analysis_server/test/lsp/signature_help_test.dart
index edaeefd..a9de8f5 100644
--- a/pkg/analysis_server/test/lsp/signature_help_test.dart
+++ b/pkg/analysis_server/test/lsp/signature_help_test.dart
@@ -305,6 +305,33 @@
     );
   }
 
+  Future<void> test_params_multipleNamed_retrigger() async {
+    final content = '''
+    /// Does foo.
+    foo(String s, {bool b = true, bool a}) {
+      foo('s',^);
+    }
+    ''';
+
+    final expectedLabel = 'foo(String s, {bool b = true, bool a})';
+    final expectedDoc = 'Does foo.';
+
+    await initialize(
+        textDocumentCapabilities: withSignatureHelpContentFormat(
+            emptyTextDocumentClientCapabilities, [MarkupKind.Markdown]));
+    await openFile(mainFileUri, withoutMarkers(content));
+    await testSignature(
+      content,
+      expectedLabel,
+      expectedDoc,
+      [
+        ParameterInformation(label: 'String s'),
+        ParameterInformation(label: 'bool b = true'),
+        ParameterInformation(label: 'bool a'),
+      ],
+    );
+  }
+
   Future<void> test_params_multipleOptional() async {
     final content = '''
     /// Does foo.
diff --git a/pkg/analysis_server/test/mocks.dart b/pkg/analysis_server/test/mocks.dart
index b8e733e..60c1114 100644
--- a/pkg/analysis_server/test/mocks.dart
+++ b/pkg/analysis_server/test/mocks.dart
@@ -155,9 +155,9 @@
   }
 
   @override
-  Description describeMismatch(
-      item, Description mismatchDescription, Map matchState, bool verbose) {
-    Response response = item;
+  Description describeMismatch(Object? item, Description mismatchDescription,
+      Map matchState, bool verbose) {
+    var response = item as Response;
     var id = response.id;
     var error = response.error;
     mismatchDescription.add('has identifier "$id"');
@@ -170,8 +170,8 @@
   }
 
   @override
-  bool matches(item, Map matchState) {
-    Response response = item;
+  bool matches(Object? item, Map matchState) {
+    var response = item as Response;
     var error = response.error;
     if (response.id != _id || error == null) {
       return false;
@@ -196,9 +196,9 @@
   }
 
   @override
-  Description describeMismatch(
-      item, Description mismatchDescription, Map matchState, bool verbose) {
-    Response? response = item;
+  Description describeMismatch(Object? item, Description mismatchDescription,
+      Map matchState, bool verbose) {
+    var response = item as Response?;
     if (response == null) {
       mismatchDescription.add('is null response');
     } else {
@@ -213,8 +213,8 @@
   }
 
   @override
-  bool matches(item, Map matchState) {
-    Response? response = item;
+  bool matches(Object? item, Map matchState) {
+    var response = item as Response?;
     return response != null && response.id == _id && response.error == null;
   }
 }
diff --git a/pkg/analysis_server/test/mocks_lsp.dart b/pkg/analysis_server/test/mocks_lsp.dart
index 35b3c1f..6c83f82 100644
--- a/pkg/analysis_server/test/mocks_lsp.dart
+++ b/pkg/analysis_server/test/mocks_lsp.dart
@@ -191,6 +191,7 @@
   /// than the maps as they would be (the server expects to do the conversion).
   T _convertJson<T>(
       lsp.ToJsonable message, T Function(Map<String, dynamic>) constructor) {
-    return constructor(jsonDecode(jsonEncode(message.toJson())));
+    return constructor(
+        jsonDecode(jsonEncode(message.toJson())) as Map<String, Object?>);
   }
 }
diff --git a/pkg/analysis_server/test/services/completion/dart/arglist_contributor_test.dart b/pkg/analysis_server/test/services/completion/dart/arglist_contributor_test.dart
index 4c2e182..f320c5f 100644
--- a/pkg/analysis_server/test/services/completion/dart/arglist_contributor_test.dart
+++ b/pkg/analysis_server/test/services/completion/dart/arglist_contributor_test.dart
@@ -6,7 +6,6 @@
 import 'package:analysis_server/src/services/completion/dart/arglist_contributor.dart';
 import 'package:analysis_server/src/services/completion/dart/completion_manager.dart';
 import 'package:analysis_server/src/services/completion/dart/suggestion_builder.dart';
-import 'package:analyzer/src/dart/analysis/experiments.dart';
 import 'package:analyzer_plugin/protocol/protocol_common.dart';
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
@@ -76,7 +75,6 @@
   /// the only suggestions.
   void assertSuggestArgumentsAndTypes(
       {required Map<String, String> namedArgumentsWithTypes,
-      List<int> requiredParamIndices = const <int>[],
       bool includeColon = true,
       bool includeComma = false}) {
     var expected = <CompletionSuggestion>[];
@@ -122,664 +120,7 @@
 @reflectiveTest
 class ArgListContributorTest extends DartCompletionContributorTest
     with ArgListContributorMixin {
-  Future<void> test_Annotation_imported_constructor_named_param() async {
-    addSource('$testPackageLibPath/a.dart', '''
-library libA; class A { const A({int one, String two: 'defaultValue'}); }''');
-    addTestSource('import "a.dart"; @A(^) main() { }');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'one': 'int', 'two': 'String'});
-  }
-
-  Future<void> test_Annotation_importedConstructor_prefixed() async {
-    addSource('$testPackageLibPath/a.dart', '''
-class A {
-  const A({int value});
-}
-''');
-    addTestSource('''
-import "a.dart" as p;
-@p.A(^)
-main() {}
-''');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {'value': 'int'});
-  }
-
-  Future<void> test_Annotation_local_constructor_named_param() async {
-    addTestSource('''
-class A { const A({int one, String two: 'defaultValue'}); }
-@A(^) main() { }''');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'one': 'int', 'two': 'String'});
-  }
-
-  @failingTest
-  Future<void> test_Annotation_local_constructor_named_param_10() async {
-    addTestSource('''
-class A { const A({int one, String two: 'defaultValue'}); }
-@A(two: '2' ^) main() { }''');
-    await computeSuggestions();
-    assertSuggestions([', one: ']);
-  }
-
-  Future<void> test_Annotation_local_constructor_named_param_11() async {
-    addTestSource('''
-class A { const A({int one, String two: 'defaultValue'}); }
-@A(two: '2', ^) main() { }''');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {'one': 'int'});
-  }
-
-  Future<void> test_Annotation_local_constructor_named_param_2() async {
-    addTestSource('''
-class A { const A({int one, String two: 'defaultValue'}); }
-@A(^ two: '2') main() { }''');
-    await computeSuggestions();
-    assertSuggestions(['one: ,']);
-  }
-
-  Future<void> test_Annotation_local_constructor_named_param_3() async {
-    addTestSource('''
-class A { const A({int one, String two: 'defaultValue'}); }
-@A(^two: '2') main() { }''');
-    await computeSuggestions();
-    assertSuggestions(['one: ,']);
-  }
-
-  Future<void> test_Annotation_local_constructor_named_param_4() async {
-    addTestSource('''
-class A { const A({int one, String two: 'defaultValue'}); }
-@A(^, two: '2') main() { }''');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {'one': 'int'});
-  }
-
-  Future<void> test_Annotation_local_constructor_named_param_5() async {
-    addTestSource('''
-class A { const A({int one, String two: 'defaultValue'}); }
-@A(^ , two: '2') main() { }''');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {'one': 'int'});
-  }
-
-  Future<void> test_Annotation_local_constructor_named_param_6() async {
-    addTestSource('''
-class A { const A(int zero, {int one, String two: 'defaultValue'}); }
-@A(0, ^, two: '2') main() { }''');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {'one': 'int'});
-  }
-
-  Future<void> test_Annotation_local_constructor_named_param_7() async {
-    addTestSource('''
-class A { const A(int zero, {int one, String two: 'defaultValue'}); }
-@A(0, ^ two: '2') main() { }''');
-    await computeSuggestions();
-    assertSuggestions(['one: ,']);
-  }
-
-  Future<void> test_Annotation_local_constructor_named_param_8() async {
-    addTestSource('''
-class A { const A(int zero, {int one, String two: 'defaultValue'}); }
-@A(0, ^two: '2') main() { }''');
-    await computeSuggestions();
-    assertSuggestions(['one: ,']);
-  }
-
-  @failingTest
-  Future<void> test_Annotation_local_constructor_named_param_9() async {
-    addTestSource('''
-class A { const A({int one, String two: 'defaultValue'}); }
-@A(two: '2'^) main() { }''');
-    await computeSuggestions();
-    assertSuggestions([', one: ']);
-  }
-
-  Future<void> test_Annotation_local_constructor_named_param_negative() async {
-    addTestSource('''
-class A { const A(int one, int two, int three, {int four, String five:
-  'defaultValue'}); }
-@A(1, ^, 3) main() { }''');
-    await computeSuggestions();
-    assertNoSuggestions();
-  }
-
-  Future<void> test_ArgumentList_closureFunction_namedParameter() async {
-    addTestSource(r'''
-void f({void Function(int a, String b) closure}) {}
-
-void main() {
-  f(closure: ^);
-}
-''');
-    await computeSuggestions();
-
-    assertSuggest(
-      '(a, b) => ,',
-      selectionOffset: 10,
-    );
-
-    assertSuggest(
-      '''
-(a, b) {
-${' ' * 4}
-${' ' * 2}},''',
-      selectionOffset: 13,
-    );
-  }
-
-  Future<void>
-      test_ArgumentList_closureFunction_namedParameter_hasComma() async {
-    addTestSource(r'''
-void f({void Function(int a, String b) closure}) {}
-
-void main() {
-  f(
-    closure: ^,
-  );
-}
-''');
-    await computeSuggestions();
-
-    assertSuggest(
-      '(a, b) => ',
-      selectionOffset: 10,
-    );
-
-    assertSuggest(
-      '''
-(a, b) {
-${' ' * 6}
-${' ' * 4}}''',
-      selectionOffset: 15,
-    );
-  }
-
-  /// todo (pq): implement positional functional parameters
-  @failingTest
-  Future<void> test_ArgumentList_closureFunction_positionalParameter() async {
-    addTestSource(r'''
-void f(void Function(int a, int b) closure) {}
-
-void main() {
-  f(^);
-}
-''');
-    await computeSuggestions();
-
-    assertSuggest(
-      '(a, b, c) => ,',
-      selectionOffset: 13,
-    );
-  }
-
-  Future<void> test_ArgumentList_closureMethod_namedParameter() async {
-    addTestSource(r'''
-class C {
-  void f({void Function(int a, String b) closure}) {}
-
-  void main() {
-    f(closure: ^);
-  }
-}
-''');
-    await computeSuggestions();
-
-    assertSuggest(
-      '(a, b) => ,',
-      selectionOffset: 10,
-    );
-
-    assertSuggest(
-      '''
-(a, b) {
-${' ' * 6}
-${' ' * 4}},''',
-      selectionOffset: 15,
-    );
-  }
-
-  Future<void> test_ArgumentList_closureParam() async {
-    addTestSource(r'''
-void f({void Function(int a, {int b, int c}) closure}) {}
-
-void main() {
-  f(closure: ^);
-}
-''');
-    await computeSuggestions();
-
-    assertSuggest(
-      '(a, {b, c}) => ,',
-      selectionOffset: 15,
-    );
-  }
-
-  Future<void> test_ArgumentList_closureParameterOptionalNamed() async {
-    addTestSource(r'''
-void f({void Function(int a, {int b, int c}) closure}) {}
-
-void main() {
-  f(closure: ^);
-}
-''');
-    await computeSuggestions();
-
-    assertSuggest(
-      '(a, {b, c}) => ,',
-      selectionOffset: 15,
-    );
-  }
-
-  Future<void> test_ArgumentList_closureParameterOptionalPositional() async {
-    addTestSource(r'''
-void f({void Function(int a, [int b, int c]) closure]) {}
-
-void main() {
-  f(closure: ^);
-}
-''');
-    await computeSuggestions();
-
-    assertSuggest(
-      '(a, [b, c]) => ,',
-      selectionOffset: 15,
-    );
-  }
-
-  Future<void> test_ArgumentList_Flutter_InstanceCreationExpression_0() async {
-    writeTestPackageConfig(flutter: true);
-
-    addTestSource('''
-import 'package:flutter/widgets.dart';
-
-build() => new Row(
-    ^
-  );
-''');
-
-    await computeSuggestions();
-
-    assertSuggest('children: [],',
-        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
-        defaultArgListString: null,
-        selectionOffset: 11,
-        defaultArgumentListTextRanges: null);
-  }
-
-  Future<void> test_ArgumentList_Flutter_InstanceCreationExpression_01() async {
-    writeTestPackageConfig(flutter: true);
-
-    addTestSource('''
-import 'package:flutter/material.dart';
-
-  build() => new Scaffold(
-        appBar: new AppBar(
-          ^
-        ),
-  );
-''');
-
-    await computeSuggestions();
-
-    assertSuggest('backgroundColor: ,',
-        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
-        defaultArgListString: null, // No default values.
-        selectionOffset: 17);
-  }
-
-  Future<void> test_ArgumentList_Flutter_InstanceCreationExpression_1() async {
-    writeTestPackageConfig(flutter: true);
-
-    addTestSource('''
-import 'package:flutter/material.dart';
-
-build() => new Row(
-    key: null,
-    ^
-  );
-''');
-
-    await computeSuggestions();
-
-    assertSuggest('children: [],',
-        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
-        defaultArgListString: null,
-        selectionOffset: 11,
-        defaultArgumentListTextRanges: null);
-  }
-
-  Future<void> test_ArgumentList_Flutter_InstanceCreationExpression_2() async {
-    writeTestPackageConfig(flutter: true);
-
-    addTestSource('''
-import 'package:flutter/material.dart';
-
-build() => new Row(
-    ^
-    key: null,
-  );
-''');
-
-    await computeSuggestions();
-
-    assertSuggest('children: [],',
-        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
-        defaultArgListString: null,
-        selectionOffset: 11,
-        defaultArgumentListTextRanges: null);
-  }
-
-  Future<void>
-      test_ArgumentList_Flutter_InstanceCreationExpression_children_dynamic() async {
-    // Ensure we don't generate unneeded <dynamic> param if a future API doesn't
-    // type it's children.
-    writeTestPackageConfig(flutter: true);
-
-    addTestSource('''
-import 'package:flutter/material.dart';
-
-build() => new Container(
-    child: new DynamicRow(^);
-  );
-
-class DynamicRow extends Widget {
-  DynamicRow({List children: null});
-}
-''');
-
-    await computeSuggestions();
-
-    assertSuggest('children: [],',
-        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
-        defaultArgListString: null,
-        selectionOffset: 11,
-        defaultArgumentListTextRanges: null);
-  }
-
-  Future<void>
-      test_ArgumentList_Flutter_InstanceCreationExpression_children_Map() async {
-    // Ensure we don't generate Map params for a future API
-    writeTestPackageConfig(flutter: true);
-
-    addTestSource('''
-import 'package:flutter/material.dart';
-
-build() => new Container(
-    child: new MapRow(^);
-  );
-
-class MapRow extends Widget {
-  MapRow({Map<Object, Object> children: null});
-}
-''');
-
-    await computeSuggestions();
-
-    assertSuggest('children: ,',
-        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
-        selectionOffset: 10,
-        defaultArgListString: null);
-  }
-
-  Future<void>
-      test_ArgumentList_Flutter_InstanceCreationExpression_slivers() async {
-    writeTestPackageConfig(flutter: true);
-
-    addTestSource('''
-import 'package:flutter/material.dart';
-
-build() => new CustomScrollView(
-    ^
-  );
-
-class CustomScrollView extends Widget {
-  CustomScrollView({List<Widget> slivers});
-}
-''');
-
-    await computeSuggestions();
-
-    assertSuggest('slivers: [],',
-        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
-        defaultArgListString: null,
-        selectionOffset: 10,
-        defaultArgumentListTextRanges: null);
-  }
-
-  Future<void> test_ArgumentList_Flutter_MethodExpression_children() async {
-    // Ensure we don't generate params for a method call
-    // TODO(brianwilkerson) This test has been changed so that it no longer has
-    // anything to do with Flutter (by moving the declaration of `foo` out of
-    // the 'material' library). Determine whether the test is still valid.
-    writeTestPackageConfig(flutter: true);
-
-    addTestSource('''
-import 'package:flutter/material.dart';
-
-main() {
-  foo(^);
-}
-
-foo({String children}) {}
-''');
-
-    await computeSuggestions();
-
-    assertSuggest('children: ',
-        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
-        defaultArgListString: null);
-  }
-
-  Future<void> test_ArgumentList_getter() async {
-    addTestSource('class A {int get foo => 7; main() {foo(^)}');
-    await computeSuggestions();
-    assertNoSuggestions();
-  }
-
-  Future<void> test_ArgumentList_imported_constructor_named_param() async {
-    // ArgumentList  InstanceCreationExpression  ExpressionStatement
-    addSource(
-        '$testPackageLibPath/a.dart', 'library libA; class A{A({int one}); }');
-    addTestSource('import "a.dart"; main() { new A(^);}');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {'one': 'int'});
-  }
-
-  Future<void> test_ArgumentList_imported_constructor_named_param2() async {
-    // ArgumentList  InstanceCreationExpression  ExpressionStatement
-    addSource('$testPackageLibPath/a.dart',
-        'library libA; class A{A.foo({int one}); }');
-    addTestSource('import "a.dart"; main() { new A.foo(^);}');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {'one': 'int'});
-  }
-
-  Future<void>
-      test_ArgumentList_imported_constructor_named_typed_param() async {
-    // ArgumentList  InstanceCreationExpression  VariableDeclaration
-    addSource('$testPackageLibPath/a.dart',
-        'library libA; class A { A({int i, String s, d}) {} }}');
-    addTestSource('import "a.dart"; main() { var a = new A(^);}');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'i': 'int', 's': 'String', 'd': 'dynamic'});
-  }
-
-  Future<void> test_ArgumentList_imported_factory_named_param() async {
-    // ArgumentList  InstanceCreationExpression  ExpressionStatement
-    addSource('$testPackageLibPath/a.dart',
-        'library libA; class A{factory A({int one}) => throw 0;}');
-    addTestSource('import "a.dart"; main() { new A(^);}');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {'one': 'int'});
-  }
-
-  Future<void> test_ArgumentList_imported_factory_named_param2() async {
-    // ArgumentList  InstanceCreationExpression  ExpressionStatement
-    addSource('$testPackageLibPath/a.dart',
-        'library libA; abstract class A{factory A.foo({int one});}');
-    addTestSource('import "a.dart"; main() { new A.foo(^);}');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {'one': 'int'});
-  }
-
-  Future<void> test_ArgumentList_imported_factory_named_typed_param() async {
-    // ArgumentList  InstanceCreationExpression  VariableDeclaration
-    addSource('$testPackageLibPath/a.dart',
-        'library libA; class A {factory A({int i, String s, d}) {} }}');
-    addTestSource('import "a.dart"; main() { var a = new A(^);}');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'i': 'int', 's': 'String', 'd': 'dynamic'});
-  }
-
-  Future<void> test_ArgumentList_imported_function_0() async {
-    // ArgumentList  MethodInvocation  ExpressionStatement  Block
-    addSource('$testPackageLibPath/a.dart', '''
-      library A;
-      bool hasLength(int expected) { }
-      expect() { }
-      void baz() { }''');
-    addTestSource('''
-      import 'a.dart'
-      class B { }
-      String bar() => true;
-      void main() {expect(a^)}''');
-    await computeSuggestions();
-    assertNoSuggestions();
-  }
-
-  Future<void> test_ArgumentList_imported_function_3a() async {
-    // ArgumentList  MethodInvocation  ExpressionStatement  Block
-    addSource('$testPackageLibPath/a.dart', '''
-      library A;
-      bool hasLength(int expected) { }
-      expect(String arg1, int arg2, {bool arg3}) { }
-      void baz() { }''');
-    addTestSource('''
-      import 'a.dart'
-      class B { }
-      String bar() => true;
-      void main() {expect('hello', ^)}''');
-    await computeSuggestions();
-    assertNoSuggestions();
-  }
-
-  Future<void> test_ArgumentList_imported_function_3b() async {
-    // ArgumentList  MethodInvocation  ExpressionStatement  Block
-    addSource('$testPackageLibPath/a.dart', '''
-      library A;
-      bool hasLength(int expected) { }
-      expect(String arg1, int arg2, {bool arg3}) { }
-      void baz() { }''');
-    addTestSource('''
-      import 'a.dart'
-      class B { }
-      String bar() => true;
-      void main() {expect('hello', ^x)}''');
-    await computeSuggestions();
-    assertNoSuggestions();
-  }
-
-  Future<void> test_ArgumentList_imported_function_3c() async {
-    // ArgumentList  MethodInvocation  ExpressionStatement  Block
-    addSource('$testPackageLibPath/a.dart', '''
-      library A;
-      bool hasLength(int expected) { }
-      expect(String arg1, int arg2, {bool arg3}) { }
-      void baz() { }''');
-    addTestSource('''
-      import 'a.dart'
-      class B { }
-      String bar() => true;
-      void main() {expect('hello', x^)}''');
-    await computeSuggestions();
-    assertNoSuggestions();
-  }
-
-  Future<void> test_ArgumentList_imported_function_3d() async {
-    // ArgumentList  MethodInvocation  ExpressionStatement  Block
-    addSource('$testPackageLibPath/a.dart', '''
-      library A;
-      bool hasLength(int expected) { }
-      expect(String arg1, int arg2, {bool arg3}) { }
-      void baz() { }''');
-    addTestSource('''
-      import 'a.dart'
-      class B { }
-      String bar() => true;
-      void main() {expect('hello', x ^)}''');
-    await computeSuggestions();
-    assertNoSuggestions();
-  }
-
-  Future<void> test_ArgumentList_imported_function_named_param() async {
-    //
-    addTestSource('main() { int.parse("16", ^);}');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {
-      'radix': 'int?',
-      'onError': 'int Function(String)?'
-    });
-  }
-
-  Future<void> test_ArgumentList_imported_function_named_param1() async {
-    //
-    addTestSource('main() { int.parse("16", r^);}');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {
-      'radix': 'int?',
-      'onError': 'int Function(String)?'
-    });
-  }
-
-  Future<void> test_ArgumentList_imported_function_named_param2() async {
-    //
-    addTestSource('main() { int.parse("16", radix: 7, ^);}');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'onError': 'int Function(String)?'});
-  }
-
-  Future<void> test_ArgumentList_imported_function_named_param2a() async {
-    //
-    addTestSource('main() { int.parse("16", radix: ^);}');
-    await computeSuggestions();
-    assertNoSuggestions();
-  }
-
-  Future<void> test_ArgumentList_imported_function_named_param_label1() async {
-    //
-    addTestSource('main() { int.parse("16", r^: 16);}');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {
-      'radix': 'int?',
-      'onError': 'int Function(String)?'
-    }, includeColon: false);
-  }
-
-  Future<void> test_ArgumentList_imported_function_named_param_label2() async {
-    //
-    addTestSource('main() { int.parse("16", ^r: 16);}');
-    await computeSuggestions();
-    assertSuggestions(['radix: ,', 'onError: ,']);
-  }
-
-  Future<void> test_ArgumentList_imported_function_named_param_label3() async {
-    //
-    addTestSource('main() { int.parse("16", ^: 16);}');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {
-      'radix': 'int?',
-      'onError': 'int Function(String)?'
-    });
-  }
-
-  Future<void>
-      test_ArgumentList_local_constructor_named_fieldFormal_documentation() async {
+  Future<void> test_fieldFormal_documentation() async {
     var content = '''
 class A {
   /// aaa
@@ -807,8 +148,7 @@
     expect(element.location!.offset, content.indexOf('fff})'));
   }
 
-  Future<void>
-      test_ArgumentList_local_constructor_named_fieldFormal_noDocumentation() async {
+  Future<void> test_fieldFormal_noDocumentation() async {
     var content = '''
 class A {
   int fff;
@@ -832,327 +172,646 @@
     expect(element.location!.offset, content.indexOf('fff})'));
   }
 
-  Future<void> test_ArgumentList_local_constructor_named_param() async {
-    //
+  Future<void> test_flutter_InstanceCreationExpression_0() async {
+    writeTestPackageConfig(flutter: true);
+
     addTestSource('''
-class A { A({int one, String two: 'defaultValue'}) { } }
-main() { new A(^);}''');
+import 'package:flutter/widgets.dart';
+
+build() => new Row(
+    ^
+  );
+''');
+
     await computeSuggestions();
 
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'one': 'int', 'two': 'String'});
-    assertSuggestArgumentAndCompletion('one',
-        completion: 'one: ', selectionOffset: 5);
+    assertSuggest('children: [],',
+        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
+        defaultArgListString: null,
+        selectionOffset: 11,
+        defaultArgumentListTextRanges: null);
   }
 
-  Future<void> test_ArgumentList_local_constructor_named_param_1() async {
-    //
+  Future<void> test_flutter_InstanceCreationExpression_01() async {
+    writeTestPackageConfig(flutter: true);
+
     addTestSource('''
-class A { A({int one, String two: 'defaultValue'}) { } }
-main() { new A(o^);}''');
+import 'package:flutter/material.dart';
+
+  build() => new Scaffold(
+        appBar: new AppBar(
+          ^
+        ),
+  );
+''');
+
     await computeSuggestions();
 
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'one': 'int', 'two': 'String'});
-    assertSuggestArgumentAndCompletion('one',
-        completion: 'one: ', selectionOffset: 5);
+    assertSuggest('backgroundColor: ,',
+        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
+        defaultArgListString: null, // No default values.
+        selectionOffset: 17);
   }
 
-  Future<void> test_ArgumentList_local_constructor_named_param_2() async {
-    //
+  Future<void> test_flutter_InstanceCreationExpression_1() async {
+    writeTestPackageConfig(flutter: true);
+
     addTestSource('''
-class A { A({int one, String two: 'defaultValue'}) { } }
-main() { new A(^o,);}''');
+import 'package:flutter/material.dart';
+
+build() => new Row(
+    key: null,
+    ^
+  );
+''');
+
     await computeSuggestions();
 
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'one': 'int', 'two': 'String'});
-    assertSuggestArgumentAndCompletion('one',
-        completion: 'one: ', selectionOffset: 5);
+    assertSuggest('children: [],',
+        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
+        defaultArgListString: null,
+        selectionOffset: 11,
+        defaultArgumentListTextRanges: null);
   }
 
-  Future<void> test_ArgumentList_local_constructor_named_param_3() async {
-    //
+  Future<void> test_flutter_InstanceCreationExpression_2() async {
+    writeTestPackageConfig(flutter: true);
+
     addTestSource('''
-class A { A({int one, String two: 'defaultValue'}) { } }
-main() { new A(two: 'foo', ^);}''');
+import 'package:flutter/material.dart';
+
+build() => new Row(
+    ^
+    key: null,
+  );
+''');
+
     await computeSuggestions();
 
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {'one': 'int'});
-    assertSuggestArgumentAndCompletion('one',
-        completion: 'one: ', selectionOffset: 5);
-  }
-
-  Future<void> test_ArgumentList_local_constructor_named_param_4() async {
-    //
-    addTestSource('''
-class A { A({int one, String two: 'defaultValue'}) { } }
-main() { new A(two: 'foo', o^);}''');
-    await computeSuggestions();
-
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {'one': 'int'});
-    assertSuggestArgumentAndCompletion('one',
-        completion: 'one: ', selectionOffset: 5);
-  }
-
-  Future<void> test_ArgumentList_local_constructor_named_param_5() async {
-    //
-    addTestSource('''
-class A { A({int one, String two: 'defaultValue'}) { } }
-main() { new A(two: 'foo', o^,);}''');
-    await computeSuggestions();
-
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {'one': 'int'});
-    assertSuggestArgumentAndCompletion('one',
-        completion: 'one: ', selectionOffset: 5);
-  }
-
-  Future<void> test_ArgumentList_local_constructor_named_param_6() async {
-    //
-    addTestSource('''
-class A { A.foo({int one, String two: 'defaultValue'}) { } }
-main() { new A.foo(^);}''');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'one': 'int', 'two': 'String'});
+    assertSuggest('children: [],',
+        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
+        defaultArgListString: null,
+        selectionOffset: 11,
+        defaultArgumentListTextRanges: null);
   }
 
   Future<void>
-      test_ArgumentList_local_constructor_named_param_prefixed_prepend() async {
-    //
+      test_flutter_InstanceCreationExpression_children_dynamic() async {
+    // Ensure we don't generate unneeded <dynamic> param if a future API doesn't
+    // type it's children.
+    writeTestPackageConfig(flutter: true);
+
     addTestSource('''
-class A { A({int one, String two: 'defaultValue'}) { } }
-main() { new A(o^ two: 'foo');}''');
-    await computeSuggestions();
+import 'package:flutter/material.dart';
 
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'one': 'int'}, includeComma: true);
-    assertSuggestArgumentAndCompletion('one',
-        completion: 'one: ,', selectionOffset: 5);
-  }
+build() => new Container(
+    child: new DynamicRow(^);
+  );
 
-  Future<void> test_ArgumentList_local_constructor_named_param_prepend() async {
-    //
-    addTestSource('''
-class A { A({int one, String two: 'defaultValue'}) { } }
-main() { new A(^ two: 'foo');}''');
-    await computeSuggestions();
-
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'one': 'int'}, includeComma: true);
-    assertSuggestArgumentAndCompletion('one',
-        completion: 'one: ,', selectionOffset: 5);
-  }
-
-  Future<void>
-      test_ArgumentList_local_constructor_named_param_prepend_1() async {
-    //
-    addTestSource('''
-class A { A({int one, String two: 'defaultValue'}) { } }
-main() { new A(o^, two: 'foo');}''');
-    await computeSuggestions();
-
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'one': 'int'}, includeComma: false);
-    assertSuggestArgumentAndCompletion('one',
-        completion: 'one: ', selectionOffset: 5);
-  }
-
-  Future<void>
-      test_ArgumentList_local_constructor_named_param_prepend_2() async {
-    //
-    addTestSource('''
-class A { A({int one, String two: 'defaultValue'}) { } }
-main() { new A(^, two: 'foo');}''');
-    await computeSuggestions();
-
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'one': 'int'}, includeComma: false);
-    assertSuggestArgumentAndCompletion('one',
-        completion: 'one: ', selectionOffset: 5);
-  }
-
-  Future<void> test_ArgumentList_local_constructor_required_param_0() async {
-    writeTestPackageConfig(meta: true);
-    addTestSource('''
-import 'package:meta/meta.dart';
-class A { A({int one, @required String two: 'defaultValue'}) { } }
-main() { new A(^);}''');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'one': 'int', 'two': 'String'},
-        requiredParamIndices: [1]);
-  }
-
-  Future<void> test_ArgumentList_local_function_3a() async {
-    // ArgumentList  MethodInvocation  ExpressionStatement  Block
-    addTestSource('''
-      expect(arg1, int arg2, {bool arg3}) { }
-      class B { }
-      String bar() => true;
-      void main() {expect('hello', ^)}''');
-    await computeSuggestions();
-    assertNoSuggestions();
-  }
-
-  Future<void> test_ArgumentList_local_function_3b() async {
-    // ArgumentList  MethodInvocation  ExpressionStatement  Block
-    addTestSource('''
-      expect(arg1, int arg2, {bool arg3}) { }
-      class B { }
-      String bar() => true;
-      void main() {expect('hello', ^x)}''');
-    await computeSuggestions();
-    assertNoSuggestions();
-  }
-
-  Future<void> test_ArgumentList_local_function_3c() async {
-    // ArgumentList  MethodInvocation  ExpressionStatement  Block
-    addTestSource('''
-      expect(arg1, int arg2, {bool arg3}) { }
-      class B { }
-      String bar() => true;
-      void main() {expect('hello', x^)}''');
-    await computeSuggestions();
-    assertNoSuggestions();
-  }
-
-  Future<void> test_ArgumentList_local_function_3d() async {
-    // ArgumentList  MethodInvocation  ExpressionStatement  Block
-    addTestSource('''
-      expect(arg1, int arg2, {bool arg3}) { }
-      class B { }
-      String bar() => true;
-      void main() {expect('hello', x ^)}''');
-    await computeSuggestions();
-    assertNoSuggestions();
-  }
-
-  Future<void> test_ArgumentList_local_function_named_param() async {
-    //
-    addTestSource('''
-f(v,{int radix, int onError(String s)}){}
-main() { f("16", ^);}''');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {
-      'radix': 'int',
-      'onError': 'int Function(String)'
-    });
-  }
-
-  Future<void> test_ArgumentList_local_function_named_param1() async {
-    //
-    addTestSource('''
-f(v,{int radix, int onError(String s)}){}
-main() { f("16", r^);}''');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {
-      'radix': 'int',
-      'onError': 'int Function(String)'
-    });
-  }
-
-  Future<void> test_ArgumentList_local_function_named_param2() async {
-    //
-    addTestSource('''
-f(v,{int radix, int onError(String s)}){}
-main() { f("16", radix: 7, ^);}''');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'onError': 'int Function(String)'});
-  }
-
-  Future<void> test_ArgumentList_local_function_named_param2a() async {
-    //
-    addTestSource('''
-f(v,{int radix, int onError(String s)}){}
-main() { f("16", radix: ^);}''');
-    await computeSuggestions();
-    assertNoSuggestions();
-  }
-
-  Future<void> test_ArgumentList_local_functionExpression_params() async {
-    // https://github.com/dart-lang/sdk/issues/42064
-    addTestSource('''
-    void main2() {
-      final add1 = ({int a}) => a + 1;
-      add1(^);
-    }
-    ''');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {'a': 'int'});
-  }
-
-  Future<void> test_ArgumentList_local_method_0() async {
-    // ArgumentList  MethodInvocation  ExpressionStatement  Block
-    addSource('$testPackageLibPath/a.dart', '''
-      library A;
-      bool hasLength(int expected) { }
-      void baz() { }''');
-    addTestSource('''
-      import 'a.dart'
-      class B {
-        expect() { }
-        void foo() {expect(^)}}
-      String bar() => true;''');
-    await computeSuggestions();
-    assertNoSuggestions();
-  }
-
-  Future<void> test_ArgumentList_nnbd_function_named_param() async {
-    addTestSource(r'''
-f({int? nullable, int nonnullable}) {}
-main() { f(^);}');
+class DynamicRow extends Widget {
+  DynamicRow({List children: null});
+}
 ''');
+
     await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {
-      'nullable': 'int?',
-      'nonnullable': 'int',
-    });
+
+    assertSuggest('children: [],',
+        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
+        defaultArgListString: null,
+        selectionOffset: 11,
+        defaultArgumentListTextRanges: null);
   }
 
-  Future<void> test_ArgumentList_nnbd_function_named_param_imported() async {
-    addSource('$testPackageLibPath/a.dart', '''
-f({int? nullable, int nonnullable}) {}''');
-    createAnalysisOptionsFile(experiments: [EnableString.non_nullable]);
-    addTestSource(r'''
-import "a.dart";
-main() { f(^);}');
-''');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {
-      'nullable': 'int?',
-      'nonnullable': 'int',
-    });
-  }
+  Future<void> test_flutter_InstanceCreationExpression_children_Map() async {
+    // Ensure we don't generate Map params for a future API
+    writeTestPackageConfig(flutter: true);
 
-  Future<void> test_ArgumentList_nnbd_function_named_param_legacy() async {
-    addSource('$testPackageLibPath/a.dart', '''
-// @dart = 2.8
-f({int named}) {}''');
-    addTestSource(r'''
-import "a.dart";
-main() { f(^);}');
-''');
-    await computeSuggestions();
-    assertSuggestArgumentsAndTypes(namedArgumentsWithTypes: {
-      'named': 'int*',
-    });
-  }
-
-  Future<void> test_superConstructorInvocation() async {
     addTestSource('''
+import 'package:flutter/material.dart';
+
+build() => new Container(
+    child: new MapRow(^);
+  );
+
+class MapRow extends Widget {
+  MapRow({Map<Object, Object> children: null});
+}
+''');
+
+    await computeSuggestions();
+
+    assertSuggest('children: ,',
+        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
+        selectionOffset: 10,
+        defaultArgListString: null);
+  }
+
+  Future<void> test_flutter_InstanceCreationExpression_slivers() async {
+    writeTestPackageConfig(flutter: true);
+
+    addTestSource('''
+import 'package:flutter/material.dart';
+
+build() => new CustomScrollView(
+    ^
+  );
+
+class CustomScrollView extends Widget {
+  CustomScrollView({List<Widget> slivers});
+}
+''');
+
+    await computeSuggestions();
+
+    assertSuggest('slivers: [],',
+        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
+        defaultArgListString: null,
+        selectionOffset: 10,
+        defaultArgumentListTextRanges: null);
+  }
+
+  Future<void> test_flutter_MethodExpression_children() async {
+    // Ensure we don't generate params for a method call
+    // TODO(brianwilkerson) This test has been changed so that it no longer has
+    // anything to do with Flutter (by moving the declaration of `foo` out of
+    // the 'material' library). Determine whether the test is still valid.
+    writeTestPackageConfig(flutter: true);
+
+    addTestSource('''
+import 'package:flutter/material.dart';
+
+main() {
+  foo(^);
+}
+
+foo({String children}) {}
+''');
+
+    await computeSuggestions();
+
+    assertSuggest('children: ',
+        csKind: CompletionSuggestionKind.NAMED_ARGUMENT,
+        defaultArgListString: null);
+  }
+
+  Future<void> test_named_01() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(^)',
+      check: () {
+        assertSuggestArgumentsAndTypes(
+          namedArgumentsWithTypes: {'one': 'bool', 'two': 'int'},
+        );
+        assertSuggestArgumentAndCompletion('one',
+            completion: 'one: ', selectionOffset: 5);
+      },
+    );
+  }
+
+  Future<void> test_named_02() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(o^)',
+      check: () {
+        assertSuggestArgumentsAndTypes(
+          namedArgumentsWithTypes: {'one': 'bool', 'two': 'int'},
+        );
+        assertSuggestArgumentAndCompletion('one',
+            completion: 'one: ', selectionOffset: 5);
+      },
+    );
+  }
+
+  Future<void> test_named_03() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(o^ two: 2)',
+      check: () {
+        assertSuggestArgumentsAndTypes(
+            namedArgumentsWithTypes: {'one': 'bool'}, includeComma: true);
+        assertSuggestArgumentAndCompletion('one',
+            completion: 'one: ,', selectionOffset: 5);
+      },
+    );
+  }
+
+  Future<void> test_named_04() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(o^, two: 2)',
+      check: () {
+        assertSuggestArgumentsAndTypes(
+            namedArgumentsWithTypes: {'one': 'bool'}, includeComma: false);
+        assertSuggestArgumentAndCompletion('one',
+            completion: 'one: ', selectionOffset: 5);
+      },
+    );
+  }
+
+  Future<void> test_named_05() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(o^ , two: 2)',
+      check: () {
+        assertSuggestArgumentsAndTypes(
+            namedArgumentsWithTypes: {'one': 'bool'}, includeComma: false);
+        assertSuggestArgumentAndCompletion('one',
+            completion: 'one: ', selectionOffset: 5);
+      },
+    );
+  }
+
+  Future<void> test_named_06() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(^o,)',
+      check: () {
+        assertSuggestArgumentsAndTypes(
+          namedArgumentsWithTypes: {'one': 'bool', 'two': 'int'},
+        );
+        assertSuggestArgumentAndCompletion('one',
+            completion: 'one: ', selectionOffset: 5);
+      },
+    );
+  }
+
+  Future<void> test_named_07() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(^ two: 2)',
+      check: () {
+        assertSuggestArgumentsAndTypes(
+            namedArgumentsWithTypes: {'one': 'bool'}, includeComma: true);
+        assertSuggestArgumentAndCompletion('one',
+            completion: 'one: ,', selectionOffset: 5);
+      },
+    );
+  }
+
+  Future<void> test_named_08() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(^two: 2)',
+      check: () {
+        assertSuggestions(['one: ,']);
+      },
+    );
+  }
+
+  Future<void> test_named_09() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(^, two: 2)',
+      check: () {
+        assertSuggestArgumentsAndTypes(
+          namedArgumentsWithTypes: {'one': 'bool'},
+          includeComma: false,
+        );
+        assertSuggestArgumentAndCompletion('one',
+            completion: 'one: ', selectionOffset: 5);
+      },
+    );
+  }
+
+  Future<void> test_named_10() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(^ , two: 2)',
+      check: () {
+        assertSuggestArgumentsAndTypes(
+          namedArgumentsWithTypes: {'one': 'bool'},
+        );
+      },
+    );
+  }
+
+  Future<void> test_named_11() async {
+    await _tryParametersArguments(
+      parameters: '(int one, {bool two, int three})',
+      arguments: '(1, ^, three: 3)',
+      check: () {
+        assertSuggestArgumentsAndTypes(
+          namedArgumentsWithTypes: {'two': 'bool'},
+        );
+      },
+    );
+  }
+
+  Future<void> test_named_12() async {
+    await _tryParametersArguments(
+      parameters: '(int one, {bool two, int three})',
+      arguments: '(1, ^ three: 3)',
+      check: () {
+        assertSuggestions(['two: ,']);
+      },
+    );
+  }
+
+  Future<void> test_named_13() async {
+    await _tryParametersArguments(
+      parameters: '(int one, {bool two, int three})',
+      arguments: '(1, ^three: 3)',
+      check: () {
+        assertSuggestions(['two: ,']);
+      },
+    );
+  }
+
+  @failingTest
+  Future<void> test_named_14() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(two: 2^)',
+      check: () {
+        assertSuggestions([', one: ']);
+      },
+    );
+  }
+
+  @failingTest
+  Future<void> test_named_15() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(two: 2 ^)',
+      check: () {
+        assertSuggestions([', one: ']);
+      },
+    );
+  }
+
+  Future<void> test_named_16() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(two: 2, ^)',
+      check: () {
+        assertSuggestArgumentsAndTypes(
+          namedArgumentsWithTypes: {'one': 'bool'},
+        );
+        assertSuggestArgumentAndCompletion('one',
+            completion: 'one: ', selectionOffset: 5);
+      },
+    );
+  }
+
+  Future<void> test_named_17() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(two: 2, o^)',
+      check: () {
+        assertSuggestArgumentsAndTypes(
+          namedArgumentsWithTypes: {'one': 'bool'},
+        );
+        assertSuggestArgumentAndCompletion('one',
+            completion: 'one: ', selectionOffset: 5);
+      },
+    );
+  }
+
+  Future<void> test_named_18() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(two: 2, o^,)',
+      check: () {
+        assertSuggestArgumentsAndTypes(
+          namedArgumentsWithTypes: {'one': 'bool'},
+        );
+        assertSuggestArgumentAndCompletion('one',
+            completion: 'one: ', selectionOffset: 5);
+      },
+    );
+  }
+
+  Future<void> test_named_19() async {
+    await _tryParametersArguments(
+      parameters: '(int one, int two, int three, {int four, int five})',
+      arguments: '(1, ^, 3)',
+      check: () {
+        assertSuggestions(['four: ', 'five: ']);
+      },
+    );
+  }
+
+  Future<void> test_named_20() async {
+    await _tryParametersArguments(
+      languageVersion: '2.15',
+      parameters: '(int one, int two, int three, {int four, int five})',
+      arguments: '(1, ^, 3)',
+      check: () {
+        assertNoSuggestions();
+      },
+    );
+  }
+
+  Future<void> test_named_21() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(o^: false)',
+      check: () {
+        assertSuggestArgumentsAndTypes(
+          namedArgumentsWithTypes: {'one': 'bool', 'two': 'int'},
+          includeColon: false,
+        );
+      },
+    );
+  }
+
+  Future<void> test_named_22() async {
+    await _tryParametersArguments(
+      parameters: '(bool one, {int two, double three})',
+      arguments: '(false, ^t: 2)',
+      check: () {
+        assertSuggestions(['two: ,', 'three: ,']);
+      },
+    );
+  }
+
+  Future<void> test_named_23() async {
+    await _tryParametersArguments(
+      parameters: '(bool one, {int two, double three})',
+      arguments: '(false, ^: 2)',
+      check: () {
+        assertSuggestArgumentsAndTypes(
+          namedArgumentsWithTypes: {'two': 'int', 'three': 'double'},
+        );
+      },
+    );
+  }
+
+  Future<void> test_named_24() async {
+    await _tryParametersArguments(
+      parameters: '({bool one, int two})',
+      arguments: '(one: ^)',
+      check: () {
+        assertNoSuggestions();
+      },
+    );
+  }
+
+  Future<void> _tryParametersArguments({
+    String? languageVersion,
+    required String parameters,
+    required String arguments,
+    required void Function() check,
+  }) async {
+    var languageVersionLine = languageVersion != null
+        ? '// @dart = $languageVersion'
+        : '// no language version override';
+
+    // Annotation, local class.
+    addTestSource2('''
+$languageVersionLine
 class A {
-  final bool field1;
-  final int field2;
-  A({this.field1, this.field2});
+  const A$parameters;
+}
+@A$arguments
+void f() {}
+''');
+    await computeSuggestions();
+    check();
+
+    // Annotation, imported class.
+    newFile('$testPackageLibPath/a.dart', content: '''
+class A {
+  const A$parameters;
+}
+''');
+    addTestSource2('''
+$languageVersionLine
+import 'a.dart';
+@A$arguments
+void f() {}
+''');
+    await computeSuggestions();
+    check();
+
+    // Annotation, imported class, prefixed.
+    newFile('$testPackageLibPath/a.dart', content: '''
+class A {
+  const A$parameters;
+}
+''');
+    addTestSource2('''
+$languageVersionLine
+import 'a.dart' as p;
+@p.A$arguments
+void f() {}
+''');
+    await computeSuggestions();
+    check();
+
+    // Function expression invocation.
+    addTestSource2('''
+$languageVersionLine
+import 'a.dart';
+void f$parameters() {}
+var v = (f)$arguments;
+''');
+    await computeSuggestions();
+    check();
+
+    // Instance creation, local class, generative.
+    addTestSource2('''
+$languageVersionLine
+class A {
+  A$parameters;
+}
+var v = A$arguments;
+''');
+    await computeSuggestions();
+    check();
+
+    // Instance creation, imported class, generative.
+    newFile('$testPackageLibPath/a.dart', content: '''
+class A {
+  A$parameters;
+}
+''');
+    addTestSource2('''
+$languageVersionLine
+import 'a.dart';
+var v = A$arguments;
+''');
+    await computeSuggestions();
+    check();
+
+    // Instance creation, imported class, factory.
+    newFile('$testPackageLibPath/a.dart', content: '''
+class A {
+  factory A$parameters => throw 0;
+}
+''');
+    addTestSource2('''
+$languageVersionLine
+import 'a.dart';
+var v = A$arguments;
+''');
+    await computeSuggestions();
+    check();
+
+    // Method invocation, local method.
+    addTestSource2('''
+$languageVersionLine
+class A {
+  void foo$parameters() {}
+}
+var v = A().foo$arguments;
+''');
+    await computeSuggestions();
+    check();
+
+    // Method invocation, local function.
+    addTestSource2('''
+$languageVersionLine
+void f$parameters() {}
+var v = f$arguments;
+''');
+    await computeSuggestions();
+    check();
+
+    // Method invocation, imported function.
+    newFile('$testPackageLibPath/a.dart', content: '''
+void f$parameters() {}
+''');
+    addTestSource2('''
+$languageVersionLine
+import 'a.dart';
+var v = f$arguments;
+''');
+    await computeSuggestions();
+    check();
+
+    // Super constructor invocation.
+    addTestSource2('''
+$languageVersionLine
+class A {
+  A$parameters;
 }
 class B extends A {
-  B() : super(^);
+  B() : super$arguments;
 }
 ''');
     await computeSuggestions();
-    assertSuggestArgumentsAndTypes(
-        namedArgumentsWithTypes: {'field1': 'bool', 'field2': 'int'});
+    check();
+
+    // This constructor invocation.
+    addTestSource2('''
+$languageVersionLine
+class A {
+  A$parameters;
+  A.named() : this$arguments;
+}
+''');
+    await computeSuggestions();
+    check();
+
+    // Invalid: getter invocation.
+    // Parameters not used. Check not used.
+    addTestSource2('''
+$languageVersionLine
+int get foo => 0;
+var v = foo$arguments;
+''');
+    await computeSuggestions();
+    assertNoSuggestions();
   }
 }
diff --git a/pkg/analysis_server/test/services/completion/dart/closure_contributor_test.dart b/pkg/analysis_server/test/services/completion/dart/closure_contributor_test.dart
new file mode 100644
index 0000000..21a2ef7
--- /dev/null
+++ b/pkg/analysis_server/test/services/completion/dart/closure_contributor_test.dart
@@ -0,0 +1,154 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analysis_server/src/provisional/completion/dart/completion_dart.dart';
+import 'package:analysis_server/src/services/completion/dart/closure_contributor.dart';
+import 'package:analysis_server/src/services/completion/dart/completion_manager.dart';
+import 'package:analysis_server/src/services/completion/dart/suggestion_builder.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import 'completion_contributor_util.dart';
+
+void main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(ClosureContributorTest);
+  });
+}
+
+@reflectiveTest
+class ClosureContributorTest extends DartCompletionContributorTest {
+  @override
+  DartCompletionContributor createContributor(
+    DartCompletionRequest request,
+    SuggestionBuilder builder,
+  ) {
+    return ClosureContributor(request, builder);
+  }
+
+  Future<void> test_argumentList_named() async {
+    addTestSource(r'''
+void f({void Function(int a, String b) closure}) {}
+
+void main() {
+  f(closure: ^);
+}
+''');
+    await computeSuggestions();
+
+    assertSuggest(
+      '(a, b) => ,',
+      selectionOffset: 10,
+    );
+
+    assertSuggest(
+      '''
+(a, b) {
+${' ' * 4}
+${' ' * 2}},''',
+      selectionOffset: 13,
+    );
+  }
+
+  Future<void> test_argumentList_named_hasComma() async {
+    addTestSource(r'''
+void f({void Function(int a, String b) closure}) {}
+
+void main() {
+  f(
+    closure: ^,
+  );
+}
+''');
+    await computeSuggestions();
+
+    assertSuggest(
+      '(a, b) => ',
+      selectionOffset: 10,
+    );
+
+    assertSuggest(
+      '''
+(a, b) {
+${' ' * 6}
+${' ' * 4}}''',
+      selectionOffset: 15,
+    );
+  }
+
+  Future<void> test_argumentList_positional() async {
+    addTestSource(r'''
+void f(void Function(int a, int b) closure) {}
+
+void main() {
+  f(^);
+}
+''');
+    await computeSuggestions();
+
+    assertSuggest(
+      '(a, b) => ,',
+      selectionOffset: 10,
+    );
+  }
+
+  Future<void> test_argumentList_positional_hasComma() async {
+    addTestSource(r'''
+void f(void Function(int a, int b) closure) {}
+
+void main() {
+  f(^,);
+}
+''');
+    await computeSuggestions();
+
+    assertSuggest(
+      '(a, b) => ',
+      selectionOffset: 10,
+    );
+  }
+
+  Future<void> test_parameters_optionalNamed() async {
+    addTestSource(r'''
+void f({void Function(int a, {int b, int c}) closure}) {}
+
+void main() {
+  f(closure: ^);
+}
+''');
+    await computeSuggestions();
+
+    assertSuggest(
+      '(a, {b, c}) => ,',
+      selectionOffset: 15,
+    );
+  }
+
+  Future<void> test_parameters_optionalPositional() async {
+    addTestSource(r'''
+void f({void Function(int a, [int b, int c]) closure]) {}
+
+void main() {
+  f(closure: ^);
+}
+''');
+    await computeSuggestions();
+
+    assertSuggest(
+      '(a, [b, c]) => ,',
+      selectionOffset: 15,
+    );
+  }
+
+  Future<void> test_variableInitializer() async {
+    addTestSource(r'''
+void Function(int a, int b) v = ^;
+''');
+    await computeSuggestions();
+
+    assertSuggest(
+      '(a, b) => ',
+      selectionOffset: 10,
+    );
+  }
+}
diff --git a/pkg/analysis_server/test/services/completion/dart/completion_contributor_util.dart b/pkg/analysis_server/test/services/completion/dart/completion_contributor_util.dart
index a8c7e39..0485895 100644
--- a/pkg/analysis_server/test/services/completion/dart/completion_contributor_util.dart
+++ b/pkg/analysis_server/test/services/completion/dart/completion_contributor_util.dart
@@ -104,6 +104,19 @@
     addSource(testFile, content);
   }
 
+  /// A variant of [addTestSource] that can be invoked more than once,
+  /// and will notify the driver that the file changed.
+  void addTestSource2(String content) {
+    _completionOffset = content.indexOf('^');
+    expect(_completionOffset, greaterThanOrEqualTo(0), reason: 'missing ^');
+    var nextOffset = content.indexOf('^', _completionOffset + 1);
+    expect(nextOffset, equals(-1), reason: 'too many ^');
+    content = content.substring(0, _completionOffset) +
+        content.substring(_completionOffset + 1);
+    addSource(testFile, content);
+    driverFor(testFile).changeFile(testFile);
+  }
+
   void assertCoreTypeSuggestions() {
     assertSuggest('Comparable');
     assertSuggest('Comparator');
diff --git a/pkg/analysis_server/test/services/completion/dart/test_all.dart b/pkg/analysis_server/test/services/completion/dart/test_all.dart
index c8ccce6..4ed7cd0 100644
--- a/pkg/analysis_server/test/services/completion/dart/test_all.dart
+++ b/pkg/analysis_server/test/services/completion/dart/test_all.dart
@@ -5,6 +5,7 @@
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
 import 'arglist_contributor_test.dart' as arglist_test;
+import 'closure_contributor_test.dart' as closure_contributor;
 import 'combinator_contributor_test.dart' as combinator_test;
 import 'completion_manager_test.dart' as completion_manager;
 import 'extension_member_contributor_test.dart' as extension_member_contributor;
@@ -27,6 +28,7 @@
 void main() {
   defineReflectiveSuite(() {
     arglist_test.main();
+    closure_contributor.main();
     combinator_test.main();
     completion_manager.main();
     extension_member_contributor.main();
diff --git a/pkg/analysis_server/test/services/completion/dart/uri_contributor_test.dart b/pkg/analysis_server/test/services/completion/dart/uri_contributor_test.dart
index 92e87d3..db354c4 100644
--- a/pkg/analysis_server/test/services/completion/dart/uri_contributor_test.dart
+++ b/pkg/analysis_server/test/services/completion/dart/uri_contributor_test.dart
@@ -24,8 +24,6 @@
 
 @reflectiveTest
 class UriContributorTest extends DartCompletionContributorTest {
-  String get testPackageTestPath => '$testPackageRootPath/test';
-
   @override
   DartCompletionContributor createContributor(
     DartCompletionRequest request,
diff --git a/pkg/analysis_server/test/services/completion/postfix/postfix_completion_test.dart b/pkg/analysis_server/test/services/completion/postfix/postfix_completion_test.dart
index dfc309c..bc6f11e 100644
--- a/pkg/analysis_server/test/services/completion/postfix/postfix_completion_test.dart
+++ b/pkg/analysis_server/test/services/completion/postfix/postfix_completion_test.dart
@@ -28,19 +28,20 @@
   late PostfixCompletionProcessor processor;
   late SourceChange change;
 
-  void _assertHasChange(String message, String expectedCode, [Function? cmp]) {
+  void _assertHasChange(String message, String expectedCode,
+      [int Function(String)? cmp]) {
     if (change.message == message) {
       if (change.edits.isNotEmpty) {
         var resultCode =
             SourceEdit.applySequence(testCode, change.edits[0].edits);
         expect(resultCode, expectedCode.replaceAll('/*caret*/', ''));
         if (cmp != null) {
-          int offset = cmp(resultCode);
+          var offset = cmp(resultCode);
           expect(change.selection!.offset, offset);
         }
       } else {
         if (cmp != null) {
-          int offset = cmp(testCode);
+          var offset = cmp(testCode);
           expect(change.selection!.offset, offset);
         }
       }
diff --git a/pkg/analysis_server/test/services/correction/sort_members_test.dart b/pkg/analysis_server/test/services/correction/sort_members_test.dart
index e434168..87042b0 100644
--- a/pkg/analysis_server/test/services/correction/sort_members_test.dart
+++ b/pkg/analysis_server/test/services/correction/sort_members_test.dart
@@ -4,6 +4,7 @@
 
 import 'package:analysis_server/src/services/correction/sort_members.dart';
 import 'package:analyzer/dart/analysis/results.dart';
+import 'package:analyzer/source/line_info.dart';
 import 'package:analyzer_plugin/protocol/protocol_common.dart';
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
@@ -18,7 +19,9 @@
 
 @reflectiveTest
 class SortMembersTest extends AbstractSingleUnitTest {
-  Future<void> test_classMembers_accessor() async {
+  LineInfo? lineInfo;
+
+  Future<void> test_class_accessor() async {
     await _parseTestUnit(r'''
 class A {
   set c(x) {}
@@ -42,7 +45,7 @@
 ''');
   }
 
-  Future<void> test_classMembers_accessor_static() async {
+  Future<void> test_class_accessor_static() async {
     await _parseTestUnit(r'''
 class A {
   get a => null;
@@ -62,7 +65,7 @@
 ''');
   }
 
-  Future<void> test_classMembers_constructor() async {
+  Future<void> test_class_constructor() async {
     await _parseTestUnit(r'''
 class A {
   A.c() {   }
@@ -82,7 +85,7 @@
 ''');
   }
 
-  Future<void> test_classMembers_external_constructorMethod() async {
+  Future<void> test_class_external_constructorMethod() async {
     await _parseTestUnit(r'''
 class Chart {
   external Pie();
@@ -98,7 +101,7 @@
 ''');
   }
 
-  Future<void> test_classMembers_field() async {
+  Future<void> test_class_field() async {
     await _parseTestUnit(r'''
 class A {
   String c;
@@ -118,7 +121,7 @@
 ''');
   }
 
-  Future<void> test_classMembers_field_static() async {
+  Future<void> test_class_field_static() async {
     await _parseTestUnit(r'''
 class A {
   int b;
@@ -138,7 +141,7 @@
 ''');
   }
 
-  Future<void> test_classMembers_method() async {
+  Future<void> test_class_method() async {
     await _parseTestUnit(r'''
 class A {
   c() {}
@@ -156,7 +159,7 @@
 ''');
   }
 
-  Future<void> test_classMembers_method_emptyLine() async {
+  Future<void> test_class_method_emptyLine() async {
     await _parseTestUnit(r'''
 class A {
   b() {}
@@ -174,7 +177,7 @@
 ''');
   }
 
-  Future<void> test_classMembers_method_ignoreCase() async {
+  Future<void> test_class_method_ignoreCase() async {
     await _parseTestUnit(r'''
 class A {
   m_C() {}
@@ -192,7 +195,7 @@
 ''');
   }
 
-  Future<void> test_classMembers_method_static() async {
+  Future<void> test_class_method_static() async {
     await _parseTestUnit(r'''
 class A {
   static a() {}
@@ -208,7 +211,7 @@
 ''');
   }
 
-  Future<void> test_classMembers_mix() async {
+  Future<void> test_class_mix() async {
     await _parseTestUnit(r'''
 class A {
   /// static field public
@@ -308,6 +311,34 @@
 ''');
   }
 
+  Future<void> test_class_trailingComments() async {
+    await _parseTestUnit(r'''
+class A { // classA
+  // instanceA
+  int instanceA; // instanceA
+  // A()
+  A(); // A()
+  // staticA
+  static int staticA; // staticA
+  // static_b
+  static int static_b; // static_b
+}
+''');
+    // validate change
+    _assertSort(r'''
+class A { // classA
+  // staticA
+  static int staticA; // staticA
+  // static_b
+  static int static_b; // static_b
+  // instanceA
+  int instanceA; // instanceA
+  // A()
+  A(); // A()
+}
+''');
+  }
+
   Future<void> test_directives() async {
     await _parseTestUnit(r'''
 library lib;
@@ -554,9 +585,73 @@
 ''');
   }
 
-  Future<void> test_mixinMembers_method() async {
+  Future<void> test_extension_accessor() async {
     await _parseTestUnit(r'''
-mixin A {
+extension E on int {
+  set c(x) {}
+  set a(x) {}
+  get a => null;
+  get b => null;
+  set b(x) {}
+  get c => null;
+}
+''');
+    // validate change
+    _assertSort(r'''
+extension E on int {
+  get a => null;
+  set a(x) {}
+  get b => null;
+  set b(x) {}
+  get c => null;
+  set c(x) {}
+}
+''');
+  }
+
+  Future<void> test_extension_accessor_static() async {
+    await _parseTestUnit(r'''
+extension E on int {
+  get a => null;
+  set a(x) {}
+  static get b => null;
+  static set b(x) {}
+}
+''');
+    // validate change
+    _assertSort(r'''
+extension E on int {
+  static get b => null;
+  static set b(x) {}
+  get a => null;
+  set a(x) {}
+}
+''');
+  }
+
+  Future<void> test_extension_field_static() async {
+    await _parseTestUnit(r'''
+extension E on int {
+  int b;
+  int a;
+  static int d;
+  static int c;
+}
+''');
+    // validate change
+    _assertSort(r'''
+extension E on int {
+  static int d;
+  static int c;
+  int b;
+  int a;
+}
+''');
+  }
+
+  Future<void> test_extension_method() async {
+    await _parseTestUnit(r'''
+extension E on int {
   c() {}
   a() {}
   b() {}
@@ -564,7 +659,7 @@
 ''');
     // validate change
     _assertSort(r'''
-mixin A {
+extension E on int {
   a() {}
   b() {}
   c() {}
@@ -572,7 +667,317 @@
 ''');
   }
 
-  Future<void> test_unitMembers_class() async {
+  Future<void> test_extension_method_emptyLine() async {
+    await _parseTestUnit(r'''
+extension E on int {
+  b() {}
+
+  a() {}
+}
+''');
+    // validate change
+    _assertSort(r'''
+extension E on int {
+  a() {}
+
+  b() {}
+}
+''');
+  }
+
+  Future<void> test_extension_method_ignoreCase() async {
+    await _parseTestUnit(r'''
+extension E on int {
+  m_C() {}
+  m_a() {}
+  m_B() {}
+}
+''');
+    // validate change
+    _assertSort(r'''
+extension E on int {
+  m_a() {}
+  m_B() {}
+  m_C() {}
+}
+''');
+  }
+
+  Future<void> test_extension_method_static() async {
+    await _parseTestUnit(r'''
+extension E on int {
+  static a() {}
+  b() {}
+}
+''');
+    // validate change
+    _assertSort(r'''
+extension E on int {
+  b() {}
+  static a() {}
+}
+''');
+  }
+
+  Future<void> test_mixin_accessor() async {
+    await _parseTestUnit(r'''
+mixin M {
+  set c(x) {}
+  set a(x) {}
+  get a => null;
+  get b => null;
+  set b(x) {}
+  get c => null;
+}
+''');
+    // validate change
+    _assertSort(r'''
+mixin M {
+  get a => null;
+  set a(x) {}
+  get b => null;
+  set b(x) {}
+  get c => null;
+  set c(x) {}
+}
+''');
+  }
+
+  Future<void> test_mixin_accessor_static() async {
+    await _parseTestUnit(r'''
+mixin M {
+  get a => null;
+  set a(x) {}
+  static get b => null;
+  static set b(x) {}
+}
+''');
+    // validate change
+    _assertSort(r'''
+mixin M {
+  static get b => null;
+  static set b(x) {}
+  get a => null;
+  set a(x) {}
+}
+''');
+  }
+
+  Future<void> test_mixin_field() async {
+    await _parseTestUnit(r'''
+mixin M {
+  String c;
+  int a;
+  void toString() => null;
+  double b;
+}
+''');
+    // validate change
+    _assertSort(r'''
+mixin M {
+  String c;
+  int a;
+  double b;
+  void toString() => null;
+}
+''');
+  }
+
+  Future<void> test_mixin_field_static() async {
+    await _parseTestUnit(r'''
+mixin M {
+  int b;
+  int a;
+  static int d;
+  static int c;
+}
+''');
+    // validate change
+    _assertSort(r'''
+mixin M {
+  static int d;
+  static int c;
+  int b;
+  int a;
+}
+''');
+  }
+
+  Future<void> test_mixin_method() async {
+    await _parseTestUnit(r'''
+mixin M {
+  c() {}
+  a() {}
+  b() {}
+}
+''');
+    // validate change
+    _assertSort(r'''
+mixin M {
+  a() {}
+  b() {}
+  c() {}
+}
+''');
+  }
+
+  Future<void> test_mixin_method_emptyLine() async {
+    await _parseTestUnit(r'''
+mixin M {
+  b() {}
+
+  a() {}
+}
+''');
+    // validate change
+    _assertSort(r'''
+mixin M {
+  a() {}
+
+  b() {}
+}
+''');
+  }
+
+  Future<void> test_mixin_method_ignoreCase() async {
+    await _parseTestUnit(r'''
+mixin M {
+  m_C() {}
+  m_a() {}
+  m_B() {}
+}
+''');
+    // validate change
+    _assertSort(r'''
+mixin M {
+  m_a() {}
+  m_B() {}
+  m_C() {}
+}
+''');
+  }
+
+  Future<void> test_mixin_method_static() async {
+    await _parseTestUnit(r'''
+mixin M {
+  static a() {}
+  b() {}
+}
+''');
+    // validate change
+    _assertSort(r'''
+mixin M {
+  b() {}
+  static a() {}
+}
+''');
+  }
+
+  Future<void> test_mixin_mix() async {
+    await _parseTestUnit(r'''
+mixin M {
+  /// static field public
+  static int nnn;
+  /// static field private
+  static int _nnn;
+  /// instance getter public
+  int get nnn => null;
+  /// instance setter public
+  set nnn(x) {}
+  /// instance getter private
+  int get _nnn => null;
+  /// instance setter private
+  set _nnn(x) {}
+  /// instance method public
+  nnn() {}
+  /// instance method private
+  _nnn() {}
+  /// static method public
+  static nnn() {}
+  /// static method private
+  static _nnn() {}
+  /// static getter public
+  static int get nnn => null;
+  /// static setter public
+  static set nnn(x) {}
+  /// static getter private
+  static int get _nnn => null;
+  /// static setter private
+  static set _nnn(x) {}
+  /// instance field public
+  int nnn;
+  /// instance field private
+  int _nnn;
+}
+''');
+    // validate change
+    _assertSort(r'''
+mixin M {
+  /// static field public
+  static int nnn;
+  /// static field private
+  static int _nnn;
+  /// static getter public
+  static int get nnn => null;
+  /// static setter public
+  static set nnn(x) {}
+  /// static getter private
+  static int get _nnn => null;
+  /// static setter private
+  static set _nnn(x) {}
+  /// instance field public
+  int nnn;
+  /// instance field private
+  int _nnn;
+  /// instance getter public
+  int get nnn => null;
+  /// instance setter public
+  set nnn(x) {}
+  /// instance getter private
+  int get _nnn => null;
+  /// instance setter private
+  set _nnn(x) {}
+  /// instance method public
+  nnn() {}
+  /// instance method private
+  _nnn() {}
+  /// static method public
+  static nnn() {}
+  /// static method private
+  static _nnn() {}
+}
+''');
+  }
+
+  Future<void> test_mixin_trailingComments() async {
+    await _parseTestUnit(r'''
+mixin M { // mixinM
+  // instanceA
+  int instanceA; // instanceA
+  // foo()
+  void foo() {} // foo()
+  // staticA
+  static int staticA; // staticA
+  // static_b
+  static int static_b; // static_b
+}
+''');
+    // validate change
+    _assertSort(r'''
+mixin M { // mixinM
+  // staticA
+  static int staticA; // staticA
+  // static_b
+  static int static_b; // static_b
+  // instanceA
+  int instanceA; // instanceA
+  // foo()
+  void foo() {} // foo()
+}
+''');
+  }
+
+  Future<void> test_unit_class() async {
     await _parseTestUnit(r'''
 class C {}
 class A {}
@@ -586,7 +991,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_class_ignoreCase() async {
+  Future<void> test_unit_class_ignoreCase() async {
     await _parseTestUnit(r'''
 class C {}
 class a {}
@@ -600,7 +1005,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_classTypeAlias() async {
+  Future<void> test_unit_classTypeAlias() async {
     await _parseTestUnit(r'''
 class M {}
 class C = Object with M;
@@ -616,7 +1021,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_directive_hasDirective() async {
+  Future<void> test_unit_directive_hasDirective() async {
     await _parseTestUnit(r'''
 library lib;
 class C {}
@@ -632,7 +1037,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_directive_noDirective_hasComment_line() async {
+  Future<void> test_unit_directive_noDirective_hasComment_line() async {
     await _parseTestUnit(r'''
 // Some comment
 
@@ -650,7 +1055,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_directive_noDirective_noComment() async {
+  Future<void> test_unit_directive_noDirective_noComment() async {
     await _parseTestUnit(r'''
 
 class B {}
@@ -666,7 +1071,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_enum() async {
+  Future<void> test_unit_enum() async {
     await _parseTestUnit(r'''
 enum C {x, y}
 enum A {x, y}
@@ -680,7 +1085,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_enumClass() async {
+  Future<void> test_unit_enumClass() async {
     await _parseTestUnit(r'''
 enum C {x, y}
 class A {}
@@ -696,7 +1101,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_extensionClass() async {
+  Future<void> test_unit_extensionClass() async {
     await _parseTestUnit(r'''
 extension E on C {}
 class C {}
@@ -708,7 +1113,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_extensions() async {
+  Future<void> test_unit_extensions() async {
     await _parseTestUnit(r'''
 extension E2 on String {}
 extension on List {}
@@ -724,7 +1129,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_function() async {
+  Future<void> test_unit_function() async {
     await _parseTestUnit(r'''
 fc() {}
 fa() {}
@@ -738,7 +1143,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_functionTypeAlias() async {
+  Future<void> test_unit_functionTypeAlias() async {
     await _parseTestUnit(r'''
 typedef FC();
 typedef FA();
@@ -752,7 +1157,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_genericTypeAlias() async {
+  Future<void> test_unit_genericTypeAlias() async {
     await _parseTestUnit(r'''
 typedef FC = void Function();
 typedef FA = void Function();
@@ -766,7 +1171,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_importsAndDeclarations() async {
+  Future<void> test_unit_importsAndDeclarations() async {
     await _parseTestUnit(r'''
 import 'dart:a';
 import 'package:b';
@@ -789,7 +1194,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_mainFirst() async {
+  Future<void> test_unit_mainFirst() async {
     await _parseTestUnit(r'''
 class C {}
 aaa() {}
@@ -809,7 +1214,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_mix() async {
+  Future<void> test_unit_mix() async {
     await _parseTestUnit(r'''
 _mmm() {}
 typedef nnn();
@@ -871,7 +1276,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_mixin() async {
+  Future<void> test_unit_mixin() async {
     await _parseTestUnit(r'''
 mixin C {}
 mixin A {}
@@ -884,7 +1289,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_topLevelVariable() async {
+  Future<void> test_unit_topLevelVariable() async {
     await _parseTestUnit(r'''
 int c;
 int a;
@@ -898,7 +1303,7 @@
 ''');
   }
 
-  Future<void> test_unitMembers_topLevelVariable_withConst() async {
+  Future<void> test_unit_topLevelVariable_withConst() async {
     await _parseTestUnit(r'''
 int c;
 int a;
@@ -916,8 +1321,40 @@
 ''');
   }
 
+  Future<void> test_unit_trailingComments() async {
+    await _parseTestUnit(r'''
+// Header
+class B {} // B
+// A
+class A {} // A
+// C
+class C {} // C
+// b
+var b; // b
+// a
+var a; // a
+// c
+var c; // c
+''');
+    // validate change
+    _assertSort(r'''
+// Header
+// a
+var a; // a
+// b
+var b; // b
+// c
+var c; // c
+// A
+class A {} // A
+class B {} // B
+// C
+class C {} // C
+''');
+  }
+
   void _assertSort(String expectedCode) {
-    var sorter = MemberSorter(testCode, testUnit);
+    var sorter = MemberSorter(testCode, testUnit, lineInfo!);
     var edits = sorter.sort();
     var result = SourceEdit.applySequence(testCode, edits);
     expect(result, expectedCode);
@@ -926,6 +1363,7 @@
   Future<void> _parseTestUnit(String code) async {
     addTestSource(code);
     var result = session.getParsedUnit(testFile) as ParsedUnitResult;
+    lineInfo = result.lineInfo;
     testUnit = result.unit;
   }
 }
diff --git a/pkg/analysis_server/test/services/refactoring/rename_class_member_test.dart b/pkg/analysis_server/test/services/refactoring/rename_class_member_test.dart
index af8c5b5..27a8207 100644
--- a/pkg/analysis_server/test/services/refactoring/rename_class_member_test.dart
+++ b/pkg/analysis_server/test/services/refactoring/rename_class_member_test.dart
@@ -738,7 +738,7 @@
   }
 
   Future<void> test_createChange_MethodElement_potential_inPubCache() async {
-    var externalPath = '/.pub-cache/aaa/lib/lib.dart';
+    var externalPath = '$packagesRootPath/aaa/lib/lib.dart';
     newFile(externalPath, content: r'''
 processObj(p) {
   p.test();
@@ -747,7 +747,7 @@
 
     writeTestPackageConfig(
       config: PackageConfigFileBuilder()
-        ..add(name: 'aaa', rootPath: '/.pub-cache/aaa/'),
+        ..add(name: 'aaa', rootPath: '$packagesRootPath/aaa'),
     );
 
     await indexTestUnit('''
diff --git a/pkg/analysis_server/test/socket_server_test.dart b/pkg/analysis_server/test/socket_server_test.dart
index 1c7bb82..1fbf2a5 100644
--- a/pkg/analysis_server/test/socket_server_test.dart
+++ b/pkg/analysis_server/test/socket_server_test.dart
@@ -10,6 +10,7 @@
 import 'package:analysis_server/src/server/error_notifier.dart';
 import 'package:analysis_server/src/socket_server.dart';
 import 'package:analysis_server/src/utilities/mocks.dart';
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:test/test.dart';
@@ -123,7 +124,7 @@
   _MockRequestHandler(this.futureException);
 
   @override
-  Response handleRequest(Request request) {
+  Response handleRequest(Request request, CancellationToken cancellationToken) {
     if (futureException) {
       Future(throwException);
       return Response(request.id);
diff --git a/pkg/analysis_server/test/src/cider/rename_test.dart b/pkg/analysis_server/test/src/cider/rename_test.dart
index 626135f..02368a6 100644
--- a/pkg/analysis_server/test/src/cider/rename_test.dart
+++ b/pkg/analysis_server/test/src/cider/rename_test.dart
@@ -8,6 +8,7 @@
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
+import '../utilities/mock_packages.dart';
 import 'cider_service.dart';
 
 void main() {
@@ -20,6 +21,22 @@
 class CiderRenameComputerTest extends CiderServiceTest {
   late _CorrectionContext _correctionContext;
 
+  @override
+  void setUp() {
+    super.setUp();
+    BazelMockPackages.instance.addFlutter(resourceProvider);
+  }
+
+  void test_canRename_class() {
+    var refactor = _compute(r'''
+class ^Old {}
+}
+''');
+
+    expect(refactor!.refactoringElement.element.name, 'Old');
+    expect(refactor.refactoringElement.offset, _correctionContext.offset);
+  }
+
   void test_canRename_field() {
     var refactor = _compute(r'''
 class A {
@@ -104,6 +121,15 @@
     expect(refactor.refactoringElement.offset, _correctionContext.offset);
   }
 
+  void test_checkName_class() {
+    var result = _checkName(r'''
+class ^Old {}
+''', 'New');
+
+    expect(result!.status.problems.length, 0);
+    expect(result.oldName, 'Old');
+  }
+
   void test_checkName_function() {
     var result = _checkName(r'''
 int ^foo() => 2;
@@ -146,6 +172,131 @@
     expect(result.oldName, 'a');
   }
 
+  void test_checkName_topLevelVariable() {
+    var result = _checkName(r'''
+var ^foo;
+''', 'bar');
+
+    expect(result!.status.problems.length, 0);
+    expect(result.oldName, 'foo');
+  }
+
+  void test_checkName_TypeAlias() {
+    var result = _checkName(r'''
+typedef ^Foo = void Function();
+''', 'Bar');
+
+    expect(result!.status.problems.length, 0);
+    expect(result.oldName, 'Foo');
+  }
+
+  void test_rename_class() {
+    var result = _rename(r'''
+class ^Old implements Other {
+  Old() {}
+  Old.named() {}
+}
+class Other {
+  factory Other.a() = Old;
+  factory Other.b() = Old.named;
+}
+void f() {
+  Old t1 = new Old();
+  Old t2 = new Old.named();
+}
+''', 'New');
+
+    expect(result!.matches.length, 1);
+    expect(result.matches, [
+      CiderSearchMatch(convertPath('/workspace/dart/test/lib/test.dart'), [
+        CharacterLocation(1, 7),
+        CharacterLocation(2, 3),
+        CharacterLocation(3, 3),
+        CharacterLocation(6, 23),
+        CharacterLocation(7, 23),
+        CharacterLocation(10, 3),
+        CharacterLocation(10, 16),
+        CharacterLocation(11, 3),
+        CharacterLocation(11, 16)
+      ])
+    ]);
+  }
+
+  void test_rename_class_flutterWidget() {
+    var result = _rename(r'''
+import 'package:flutter/material.dart';
+
+class ^TestPage extends StatefulWidget {
+  const TestPage();
+
+  @override
+  State<TestPage> createState() => TestPageState();
+}
+
+class TestPageState extends State<TestPage> {
+  @override
+  Widget build(BuildContext context) => throw 0;
+}
+''', 'NewPage');
+
+    expect(result!.matches.length, 1);
+    expect(result.matches, [
+      CiderSearchMatch(convertPath('/workspace/dart/test/lib/test.dart'), [
+        CharacterLocation(3, 7),
+        CharacterLocation(4, 9),
+        CharacterLocation(7, 9),
+        CharacterLocation(10, 35)
+      ])
+    ]);
+    expect(result.flutterWidgetRename != null, isTrue);
+    expect(result.flutterWidgetRename!.name, 'NewPageState');
+    expect(result.flutterWidgetRename!.matches, [
+      CiderSearchMatch(convertPath('/workspace/dart/test/lib/test.dart'),
+          [CharacterLocation(7, 36), CharacterLocation(10, 7)])
+    ]);
+  }
+
+  void test_rename_function() {
+    var result = _rename(r'''
+test() {}
+^foo() {}
+void f() {
+  print(test);
+  print(test());
+  foo();
+}
+''', 'bar');
+
+    expect(result!.matches.length, 1);
+    expect(result.matches, [
+      CiderSearchMatch(convertPath('/workspace/dart/test/lib/test.dart'), [
+        CharacterLocation(2, 1),
+        CharacterLocation(6, 3),
+      ])
+    ]);
+  }
+
+  void test_rename_function_imported() {
+    var a = newFile('/workspace/dart/test/lib/a.dart', content: r'''
+foo() {}
+''');
+    fileResolver.resolve(path: a.path);
+    var result = _rename(r'''
+import 'a.dart';
+void f() {
+  ^foo();
+}
+''', 'bar');
+    expect(result!.matches.length, 2);
+    expect(result.matches, [
+      CiderSearchMatch(convertPath('/workspace/dart/test/lib/a.dart'), [
+        CharacterLocation(1, 1),
+      ]),
+      CiderSearchMatch(convertPath('/workspace/dart/test/lib/test.dart'),
+          [CharacterLocation(3, 3)])
+    ]);
+  }
+
   void test_rename_local() {
     var result = _rename(r'''
 void foo() {
@@ -160,31 +311,6 @@
             [CharacterLocation(2, 7), CharacterLocation(2, 22)]));
   }
 
-  void test_rename_method() {
-    var a = newFile('/workspace/dart/test/lib/a.dart', content: r'''
-void foo() {
-  a;
-}
-''');
-    fileResolver.resolve(path: a.path);
-
-    var result = _rename(r'''
-import 'a.dart';
-
-main() {
-^foo();
-}
-''', 'bar');
-
-    expect(result!.matches.length, 2);
-    expect(result.matches, [
-      CiderSearchMatch(convertPath('/workspace/dart/test/lib/a.dart'),
-          [CharacterLocation(1, 6)]),
-      CiderSearchMatch(convertPath('/workspace/dart/test/lib/test.dart'),
-          [CharacterLocation(4, 1)])
-    ]);
-  }
-
   void test_rename_parameter() {
     var result = _rename(r'''
 void foo(String ^a) {
@@ -195,6 +321,38 @@
     expect(result.checkName.oldName, 'a');
   }
 
+  void test_rename_propertyAccessor() {
+    var result = _rename(r'''
+get foo {}
+set foo(x) {}
+void f() {
+  print(foo);
+  ^foo = 1;
+  foo += 2;
+''', 'bar');
+    expect(result!.matches, [
+      CiderSearchMatch(convertPath('/workspace/dart/test/lib/test.dart'),
+          [CharacterLocation(1, 5), CharacterLocation(4, 9)]),
+      CiderSearchMatch(convertPath('/workspace/dart/test/lib/test.dart'), [
+        CharacterLocation(2, 5),
+        CharacterLocation(5, 3),
+        CharacterLocation(6, 3)
+      ])
+    ]);
+  }
+
+  void test_typeAlias_functionType() {
+    var result = _rename(r'''
+typedef ^F = void Function();
+void f(F a) {}
+''', 'bar');
+
+    expect(result!.matches, [
+      CiderSearchMatch(convertPath('/workspace/dart/test/lib/test.dart'),
+          [CharacterLocation(1, 9), CharacterLocation(2, 8)])
+    ]);
+  }
+
   CheckNameResponse? _checkName(String content, String newName) {
     _updateFile(content);
 
@@ -221,7 +379,7 @@
     );
   }
 
-  RenameResponse? _rename(String content, newName) {
+  RenameResponse? _rename(String content, String newName) {
     _updateFile(content);
 
     return CiderRenameComputer(
diff --git a/pkg/analysis_server/test/src/cider/signature_help_test.dart b/pkg/analysis_server/test/src/cider/signature_help_test.dart
new file mode 100644
index 0000000..2b99d72
--- /dev/null
+++ b/pkg/analysis_server/test/src/cider/signature_help_test.dart
@@ -0,0 +1,253 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analysis_server/lsp_protocol/protocol_generated.dart';
+import 'package:analysis_server/src/cider/signature_help.dart';
+import 'package:analyzer/source/line_info.dart';
+import 'package:collection/collection.dart';
+import 'package:test/test.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import 'cider_service.dart';
+
+void main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(CiderSignatureHelpComputerTest);
+  });
+}
+
+@reflectiveTest
+class CiderSignatureHelpComputerTest extends CiderServiceTest {
+  late _CorrectionContext _correctionContext;
+
+  void test_noDefaultConstructor() {
+    var result = _compute('''
+class A {
+  A._();
+}
+
+final a = A(^);
+''');
+
+    expect(result, null);
+  }
+
+  void test_params_multipleNamed() {
+    final content = '''
+/// Does foo.
+foo(String s, {bool b = true, bool a}) {
+  foo(^);
+}
+''';
+    final expectedLabel = 'foo(String s, {bool b = true, bool a})';
+
+    testSignature(
+        content,
+        expectedLabel,
+        'Does foo.',
+        [
+          ParameterInformation(label: 'String s'),
+          ParameterInformation(label: 'bool b = true'),
+          ParameterInformation(label: 'bool a'),
+        ],
+        CharacterLocation(3, 7));
+  }
+
+  void test_params_multipleOptional() {
+    final content = '''
+/// Does foo.
+foo(String s, [bool b = true, bool a]) {
+  foo(^);
+}
+''';
+
+    final expectedLabel = 'foo(String s, [bool b = true, bool a])';
+    testSignature(
+        content,
+        expectedLabel,
+        'Does foo.',
+        [
+          ParameterInformation(label: 'String s'),
+          ParameterInformation(label: 'bool b = true'),
+          ParameterInformation(label: 'bool a'),
+        ],
+        CharacterLocation(3, 7));
+  }
+
+  void test_retrigger_validLocation() {
+    final content = '''
+/// Does foo.
+foo(String s, {bool b = true, bool a}) {
+  foo('ssss',^);
+}
+''';
+    final expectedLabel = 'foo(String s, {bool b = true, bool a})';
+
+    testSignature(
+        content,
+        expectedLabel,
+        'Does foo.',
+        [
+          ParameterInformation(label: 'String s'),
+          ParameterInformation(label: 'bool b = true'),
+          ParameterInformation(label: 'bool a'),
+        ],
+        CharacterLocation(3, 7));
+  }
+
+  void test_simple() {
+    final content = '''
+/// Does foo.
+foo(String s, int i) {
+  foo(^);
+}
+''';
+    final expectedLabel = 'foo(String s, int i)';
+    testSignature(
+        content,
+        expectedLabel,
+        'Does foo.',
+        [
+          ParameterInformation(label: 'String s'),
+          ParameterInformation(label: 'int i'),
+        ],
+        CharacterLocation(3, 7));
+  }
+
+  void test_triggerCharacter_validLocation() {
+    final content = '''
+/// Does foo.
+foo(String s, int i) {
+  foo(^
+}
+''';
+
+    final expectedLabel = 'foo(String s, int i)';
+    testSignature(
+        content,
+        expectedLabel,
+        'Does foo.',
+        [
+          ParameterInformation(label: 'String s'),
+          ParameterInformation(label: 'int i'),
+        ],
+        CharacterLocation(3, 7));
+  }
+
+  void test_typeParams_class() {
+    final content = '''
+/// My Foo.
+class Foo<T1, T2 extends String> {}
+
+class Bar extends Foo<^> {}
+''';
+
+    testSignature(
+        content,
+        'class Foo<T1, T2 extends String>',
+        'My Foo.',
+        [
+          ParameterInformation(label: 'T1'),
+          ParameterInformation(label: 'T2 extends String')
+        ],
+        CharacterLocation(4, 23));
+  }
+
+  void test_typeParams_function() {
+    final content = '''
+/// My Foo.
+void foo<T1, T2 extends String>() {
+  foo<^>();
+}
+''';
+
+    testSignature(
+        content,
+        'void foo<T1, T2 extends String>()',
+        'My Foo.',
+        [
+          ParameterInformation(label: 'T1'),
+          ParameterInformation(label: 'T2 extends String')
+        ],
+        CharacterLocation(3, 7));
+  }
+
+  void test_typeParams_method() {
+    final content = '''
+class Foo {
+  /// My Foo.
+  void foo<T1, T2 extends String>() {
+    foo<^>();
+  }
+}
+''';
+
+    testSignature(
+        content,
+        'void foo<T1, T2 extends String>()',
+        'My Foo.',
+        [
+          ParameterInformation(label: 'T1'),
+          ParameterInformation(label: 'T2 extends String')
+        ],
+        CharacterLocation(4, 9));
+  }
+
+  void testSignature(
+      String content,
+      String expectedLabel,
+      String expectedDoc,
+      List<ParameterInformation> expectedParameters,
+      CharacterLocation leftParenLocation) {
+    var result = _compute(content);
+    var signature = result!.signatureHelp.signatures.first;
+    final expected =
+        MarkupContent(kind: MarkupKind.Markdown, value: expectedDoc);
+    expect(signature.label, expectedLabel);
+    expect(signature.documentation!.valueEquals(expected), isTrue);
+    expect(ListEquality().equals(expectedParameters, signature.parameters),
+        isTrue);
+    expect(result.callStart == leftParenLocation, isTrue);
+  }
+
+  SignatureHelpResponse? _compute(String content) {
+    _updateFile(content);
+
+    return CiderSignatureHelpComputer(
+      fileResolver,
+    ).compute(
+      convertPath(testPath),
+      _correctionContext.line,
+      _correctionContext.character,
+    );
+  }
+
+  void _updateFile(String content) {
+    var offset = content.indexOf('^');
+    expect(offset, isPositive, reason: 'Expected to find ^');
+    expect(content.indexOf('^', offset + 1), -1, reason: 'Expected only one ^');
+
+    var lineInfo = LineInfo.fromContent(content);
+    var location = lineInfo.getLocation(offset);
+
+    content = content.substring(0, offset) + content.substring(offset + 1);
+    newFile(testPath, content: content);
+
+    _correctionContext = _CorrectionContext(
+      content,
+      offset,
+      location.lineNumber - 1,
+      location.columnNumber - 1,
+    );
+  }
+}
+
+class _CorrectionContext {
+  final String content;
+  final int offset;
+  final int line;
+  final int character;
+
+  _CorrectionContext(this.content, this.offset, this.line, this.character);
+}
diff --git a/pkg/analysis_server/test/src/cider/test_all.dart b/pkg/analysis_server/test/src/cider/test_all.dart
index 95c39ca..2220710 100644
--- a/pkg/analysis_server/test/src/cider/test_all.dart
+++ b/pkg/analysis_server/test/src/cider/test_all.dart
@@ -8,6 +8,7 @@
 import 'completion_test.dart' as completion;
 import 'fixes_test.dart' as fixes;
 import 'rename_test.dart' as rename;
+import 'signature_help_test.dart' as signature;
 
 void main() {
   defineReflectiveSuite(() {
@@ -15,5 +16,6 @@
     completion.main();
     fixes.main();
     rename.main();
+    signature.main();
   });
 }
diff --git a/pkg/analysis_server/test/src/computer/outline_computer_test.dart b/pkg/analysis_server/test/src/computer/outline_computer_test.dart
index 7a0837e..c215a6c 100644
--- a/pkg/analysis_server/test/src/computer/outline_computer_test.dart
+++ b/pkg/analysis_server/test/src/computer/outline_computer_test.dart
@@ -123,7 +123,7 @@
     void writeOutline(Outline outline, String indent) {
       buffer.write(indent);
       buffer.writeln(outline.element.name);
-      for (var child in outline.children ?? const []) {
+      for (var child in outline.children ?? const <Outline>[]) {
         writeOutline(child, '$indent  ');
       }
     }
diff --git a/pkg/analysis_server/test/src/domain_abstract_test.dart b/pkg/analysis_server/test/src/domain_abstract_test.dart
index 1116cbf..5a64d54 100644
--- a/pkg/analysis_server/test/src/domain_abstract_test.dart
+++ b/pkg/analysis_server/test/src/domain_abstract_test.dart
@@ -2,9 +2,11 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+import 'package:analysis_server/src/analysis_server.dart';
 import 'package:analysis_server/src/domain_abstract.dart';
 import 'package:analysis_server/src/plugin/plugin_manager.dart';
 import 'package:analysis_server/src/protocol_server.dart' hide Element;
+import 'package:analysis_server/src/utilities/progress.dart';
 import 'package:analyzer/instrumentation/service.dart';
 import 'package:analyzer_plugin/protocol/protocol.dart' as plugin;
 import 'package:analyzer_plugin/protocol/protocol_generated.dart' as plugin;
@@ -92,10 +94,10 @@
 }
 
 class TestAbstractRequestHandler extends AbstractRequestHandler {
-  TestAbstractRequestHandler(server) : super(server);
+  TestAbstractRequestHandler(AnalysisServer server) : super(server);
 
   @override
-  Response handleRequest(Request request) {
+  Response handleRequest(Request request, CancellationToken cancellationToken) {
     fail('Unexpected invocation of handleRequest');
   }
 }
diff --git a/pkg/analysis_server/test/src/services/correction/fix/add_return_null_test.dart b/pkg/analysis_server/test/src/services/correction/fix/add_return_null_test.dart
new file mode 100644
index 0000000..f12fd37
--- /dev/null
+++ b/pkg/analysis_server/test/src/services/correction/fix/add_return_null_test.dart
@@ -0,0 +1,125 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analysis_server/src/services/correction/fix.dart';
+import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import 'fix_processor.dart';
+
+void main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(AddReturnNullBulkTest);
+    defineReflectiveTests(AddReturnNullTest);
+  });
+}
+
+@reflectiveTest
+class AddReturnNullBulkTest extends BulkFixProcessorTest {
+  Future<void> test_singleFile() async {
+    await resolveTestCode('''
+int? f() {
+  // ignore: unused_element
+  int? g() {
+    if (1 == 2) return 5;
+  }
+  if (1 == 2) return 7;
+}
+''');
+    await assertHasFix('''
+int? f() {
+  // ignore: unused_element
+  int? g() {
+    if (1 == 2) return 5;
+    return null;
+  }
+  if (1 == 2) return 7;
+  return null;
+}
+''');
+  }
+}
+
+@reflectiveTest
+class AddReturnNullTest extends FixProcessorTest {
+  @override
+  FixKind get kind => DartFixKind.ADD_RETURN_NULL;
+
+  Future<void> test_functionExpression() async {
+    await resolveTestCode('''
+int? Function() f = () {
+  if (1 == 2) return 7;
+};
+''');
+    await assertHasFix('''
+int? Function() f = () {
+  if (1 == 2) return 7;
+  return null;
+};
+''');
+  }
+
+  Future<void> test_functionExpression_empty() async {
+    await resolveTestCode('''
+int? Function() f = () {};
+''');
+    await assertHasFix('''
+int? Function() f = () {
+  return null;
+};
+''');
+  }
+
+  Future<void> test_localFunction() async {
+    await resolveTestCode('''
+void m() {
+  // ignore: unused_element
+  int? f() {
+    if (1 == 2) return 7;
+  }
+}
+''');
+    await assertHasFix('''
+void m() {
+  // ignore: unused_element
+  int? f() {
+    if (1 == 2) return 7;
+    return null;
+  }
+}
+''');
+  }
+
+  Future<void> test_method() async {
+    await resolveTestCode('''
+class A {
+  int? m() {
+    if (1 == 2) return 7;
+  }
+}
+''');
+    await assertHasFix('''
+class A {
+  int? m() {
+    if (1 == 2) return 7;
+    return null;
+  }
+}
+''');
+  }
+
+  Future<void> test_topLevelFunction_block() async {
+    await resolveTestCode('''
+int? f() {
+  if (1 == 2) return 7;
+}
+''');
+    await assertHasFix('''
+int? f() {
+  if (1 == 2) return 7;
+  return null;
+}
+''');
+  }
+}
diff --git a/pkg/analysis_server/test/src/services/correction/fix/create_constructor_super_test.dart b/pkg/analysis_server/test/src/services/correction/fix/create_constructor_super_test.dart
index 5a61202..6095520 100644
--- a/pkg/analysis_server/test/src/services/correction/fix/create_constructor_super_test.dart
+++ b/pkg/analysis_server/test/src/services/correction/fix/create_constructor_super_test.dart
@@ -104,7 +104,7 @@
 ''');
   }
 
-  Future<void> test_named() async {
+  Future<void> test_namedConstructor() async {
     await resolveTestCode('''
 class A {
   A.named(p1, int p2);
@@ -129,6 +129,56 @@
 ''');
   }
 
+  Future<void> test_namedOptionalParams() async {
+    await resolveTestCode('''
+class A {
+  A(p1, int p2, List<String> p3, {int? p4});
+}
+class B extends A {
+  int existingField = 0;
+
+  void existingMethod() {}
+}
+''');
+    await assertHasFix('''
+class A {
+  A(p1, int p2, List<String> p3, {int? p4});
+}
+class B extends A {
+  int existingField = 0;
+
+  B(p1, int p2, List<String> p3) : super(p1, p2, p3);
+
+  void existingMethod() {}
+}
+''');
+  }
+
+  Future<void> test_namedRequiredParams() async {
+    await resolveTestCode('''
+class A {
+  A(p1, int p2, List<String> p3, {required int p4, required int p5});
+}
+class B extends A {
+  int existingField = 0;
+
+  void existingMethod() {}
+}
+''');
+    await assertHasFix('''
+class A {
+  A(p1, int p2, List<String> p3, {required int p4, required int p5});
+}
+class B extends A {
+  int existingField = 0;
+
+  B(p1, int p2, List<String> p3, {required int p4, required int p5}) : super(p1, p2, p3, p4: p4, p5: p5);
+
+  void existingMethod() {}
+}
+''');
+  }
+
   Future<void> test_optional() async {
     await resolveTestCode('''
 class A {
diff --git a/pkg/analysis_server/test/src/services/correction/fix/data_driven/add_type_parameter_test.dart b/pkg/analysis_server/test/src/services/correction/fix/data_driven/add_type_parameter_test.dart
index fab212b..dff9c05 100644
--- a/pkg/analysis_server/test/src/services/correction/fix/data_driven/add_type_parameter_test.dart
+++ b/pkg/analysis_server/test/src/services/correction/fix/data_driven/add_type_parameter_test.dart
@@ -477,13 +477,17 @@
   /// Return the kind of element whose parameters are being modified.
   String get _kind;
 
-  Transform _add(int index, {List<String>? components, String? extendedType}) =>
+  Transform _add(int index,
+          {List<String>? components,
+          String? extendedType,
+          bool isStatic = false}) =>
       Transform(
           title: 'title',
           date: DateTime.now(),
           element: ElementDescriptor(
               libraryUris: [Uri.parse(importUri)],
               kind: ElementKindUtilities.fromName(_kind)!,
+              isStatic: isStatic,
               components: components ?? ['m', 'C']),
           bulkApply: false,
           changesSelector: UnconditionalChangesSelector([
diff --git a/pkg/analysis_server/test/src/services/correction/fix/data_driven/diagnostics/test_all.dart b/pkg/analysis_server/test/src/services/correction/fix/data_driven/diagnostics/test_all.dart
index 375c983..6ec3458 100644
--- a/pkg/analysis_server/test/src/services/correction/fix/data_driven/diagnostics/test_all.dart
+++ b/pkg/analysis_server/test/src/services/correction/fix/data_driven/diagnostics/test_all.dart
@@ -23,6 +23,7 @@
 import 'unexpected_token_test.dart' as unexpected_token;
 import 'unknown_accessor_test.dart' as unknown_accessor;
 import 'unsupported_key_test.dart' as unsupported_key;
+import 'unsupported_static_test.dart' as unsupported_static;
 import 'unsupported_uri_change_test.dart' as unsupported_uri_change;
 import 'unsupported_version_test.dart' as unsupported_version;
 import 'wrong_token_test.dart' as wrong_token;
@@ -49,6 +50,7 @@
     unexpected_token.main();
     unknown_accessor.main();
     unsupported_key.main();
+    unsupported_static.main();
     unsupported_uri_change.main();
     unsupported_version.main();
     wrong_token.main();
diff --git a/pkg/analysis_server/test/src/services/correction/fix/data_driven/diagnostics/unsupported_static_test.dart b/pkg/analysis_server/test/src/services/correction/fix/data_driven/diagnostics/unsupported_static_test.dart
new file mode 100644
index 0000000..2ef1446
--- /dev/null
+++ b/pkg/analysis_server/test/src/services/correction/fix/data_driven/diagnostics/unsupported_static_test.dart
@@ -0,0 +1,64 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analysis_server/src/services/correction/fix/data_driven/transform_set_error_code.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import '../transform_set_parser_test_support.dart';
+
+void main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(UnsupportedStaticTest);
+  });
+}
+
+@reflectiveTest
+class UnsupportedStaticTest extends AbstractTransformSetParserTest {
+  void test_class() {
+    assertErrors('''
+version: 1
+transforms:
+- title: ''
+  date: 2021-11-22
+  element:
+    uris: ['test.dart']
+    class: 'C'
+    static: true
+  changes: []
+''', [
+      error(TransformSetErrorCode.unsupportedStatic, 108, 6),
+    ]);
+  }
+
+  void test_getter_inClass() {
+    assertNoErrors('''
+version: 1
+transforms:
+- title: ''
+  date: 2021-11-22
+  element:
+    uris: ['test.dart']
+    getter: 'm'
+    inClass: 'C'
+    static: true
+  changes: []
+''');
+  }
+
+  void test_getter_topLevel() {
+    assertErrors('''
+version: 1
+transforms:
+- title: ''
+  date: 2021-11-22
+  element:
+    uris: ['test.dart']
+    getter: 'g'
+    static: true
+  changes: []
+''', [
+      error(TransformSetErrorCode.unsupportedStatic, 109, 6),
+    ]);
+  }
+}
diff --git a/pkg/analysis_server/test/src/services/correction/fix/data_driven/modify_parameters_test.dart b/pkg/analysis_server/test/src/services/correction/fix/data_driven/modify_parameters_test.dart
index 535320f..8fcb8d5 100644
--- a/pkg/analysis_server/test/src/services/correction/fix/data_driven/modify_parameters_test.dart
+++ b/pkg/analysis_server/test/src/services/correction/fix/data_driven/modify_parameters_test.dart
@@ -1006,13 +1006,15 @@
   String get _kind;
 
   Transform _modify(List<String> originalComponents,
-          List<ParameterModification> modifications, {String? newName}) =>
+          List<ParameterModification> modifications,
+          {String? newName, bool isStatic = false}) =>
       Transform(
           title: 'title',
           date: DateTime.now(),
           element: ElementDescriptor(
               libraryUris: [Uri.parse(importUri)],
               kind: ElementKindUtilities.fromName(_kind)!,
+              isStatic: isStatic,
               components: originalComponents),
           bulkApply: false,
           changesSelector: UnconditionalChangesSelector([
diff --git a/pkg/analysis_server/test/src/services/correction/fix/data_driven/rename_parameter_test.dart b/pkg/analysis_server/test/src/services/correction/fix/data_driven/rename_parameter_test.dart
index 59d5f50..eb0bafa 100644
--- a/pkg/analysis_server/test/src/services/correction/fix/data_driven/rename_parameter_test.dart
+++ b/pkg/analysis_server/test/src/services/correction/fix/data_driven/rename_parameter_test.dart
@@ -328,13 +328,15 @@
   /// Return the kind of element containing the parameter being renamed.
   String get _kind;
 
-  Transform _rename(List<String> components, String oldName, String newName) =>
+  Transform _rename(List<String> components, String oldName, String newName,
+          {bool isStatic = false}) =>
       Transform(
           title: 'title',
           date: DateTime.now(),
           element: ElementDescriptor(
               libraryUris: [Uri.parse(importUri)],
               kind: ElementKindUtilities.fromName(_kind)!,
+              isStatic: isStatic,
               components: components),
           bulkApply: false,
           changesSelector: UnconditionalChangesSelector([
diff --git a/pkg/analysis_server/test/src/services/correction/fix/data_driven/rename_test.dart b/pkg/analysis_server/test/src/services/correction/fix/data_driven/rename_test.dart
index cf1aeb9..d39a127 100644
--- a/pkg/analysis_server/test/src/services/correction/fix/data_driven/rename_test.dart
+++ b/pkg/analysis_server/test/src/services/correction/fix/data_driven/rename_test.dart
@@ -1533,15 +1533,18 @@
   /// Return the kind of element being renamed.
   String get _kind;
 
-  Transform _rename(List<String> components, String newName) => Transform(
-      title: 'title',
-      date: DateTime.now(),
-      element: ElementDescriptor(
-          libraryUris: [Uri.parse(importUri)],
-          kind: ElementKindUtilities.fromName(_kind)!,
-          components: components),
-      bulkApply: false,
-      changesSelector: UnconditionalChangesSelector([
-        Rename(newName: newName),
-      ]));
+  Transform _rename(List<String> components, String newName,
+          {bool isStatic = false}) =>
+      Transform(
+          title: 'title',
+          date: DateTime.now(),
+          element: ElementDescriptor(
+              libraryUris: [Uri.parse(importUri)],
+              kind: ElementKindUtilities.fromName(_kind)!,
+              isStatic: isStatic,
+              components: components),
+          bulkApply: false,
+          changesSelector: UnconditionalChangesSelector([
+            Rename(newName: newName),
+          ]));
 }
diff --git a/pkg/analysis_server/test/src/services/correction/fix/data_driven/replaced_by_test.dart b/pkg/analysis_server/test/src/services/correction/fix/data_driven/replaced_by_test.dart
index 03d89fe..a7b70a4 100644
--- a/pkg/analysis_server/test/src/services/correction/fix/data_driven/replaced_by_test.dart
+++ b/pkg/analysis_server/test/src/services/correction/fix/data_driven/replaced_by_test.dart
@@ -838,12 +838,19 @@
   }
 
   Transform _replacedBy(ElementKind oldKind, List<String> oldComponents,
-      ElementKind newKind, List<String> newComponents) {
+      ElementKind newKind, List<String> newComponents,
+      {bool isStatic = false}) {
     var uris = [Uri.parse(importUri)];
     var oldElement = ElementDescriptor(
-        libraryUris: uris, kind: oldKind, components: oldComponents);
+        libraryUris: uris,
+        kind: oldKind,
+        isStatic: isStatic,
+        components: oldComponents);
     var newElement2 = ElementDescriptor(
-        libraryUris: uris, kind: newKind, components: newComponents);
+        libraryUris: uris,
+        kind: newKind,
+        isStatic: isStatic,
+        components: newComponents);
     return Transform(
         title: 'title',
         date: DateTime.now(),
diff --git a/pkg/analysis_server/test/src/services/correction/fix/data_driven/transform_override_set_parser_test.dart b/pkg/analysis_server/test/src/services/correction/fix/data_driven/transform_override_set_parser_test.dart
index af7b127..9d4c388 100644
--- a/pkg/analysis_server/test/src/services/correction/fix/data_driven/transform_override_set_parser_test.dart
+++ b/pkg/analysis_server/test/src/services/correction/fix/data_driven/transform_override_set_parser_test.dart
@@ -15,7 +15,7 @@
 
 void main() {
   defineReflectiveSuite(() {
-    defineReflectiveTests(TransformSetParserTest);
+    defineReflectiveTests(TransformOverrideSetParserTest);
   });
 }
 
@@ -64,7 +64,8 @@
 }
 
 @reflectiveTest
-class TransformSetParserTest extends AbstractTransformOverrideSetParserTest {
+class TransformOverrideSetParserTest
+    extends AbstractTransformOverrideSetParserTest {
   void test_emptyFile() {
     assertErrors('''
 ''', [error(TransformSetErrorCode.invalidValue, 0, 0)]);
diff --git a/pkg/analysis_server/test/src/services/correction/fix/data_driven/transform_set_parser_test.dart b/pkg/analysis_server/test/src/services/correction/fix/data_driven/transform_set_parser_test.dart
index 51421b4..95055f4 100644
--- a/pkg/analysis_server/test/src/services/correction/fix/data_driven/transform_set_parser_test.dart
+++ b/pkg/analysis_server/test/src/services/correction/fix/data_driven/transform_set_parser_test.dart
@@ -525,6 +525,32 @@
     var transform = transforms[0];
     expect(transform.title, 'Rename m');
     expect(_changes(transform), isEmpty);
+    var element = transform.element;
+    expect(element.components, ['m', 'A']);
+    expect(element.isStatic, isFalse);
+  }
+
+  void test_element_method_inExtension_static() {
+    assertNoErrors('''
+version: 1
+transforms:
+- title: 'Rename m'
+  date: 2020-09-02
+  element:
+    uris: ['test.dart']
+    method: 'm'
+    inExtension: 'E'
+    static: true
+  changes: []
+''');
+    var transforms = _transforms('m');
+    expect(transforms, hasLength(1));
+    var transform = transforms[0];
+    expect(transform.title, 'Rename m');
+    expect(_changes(transform), isEmpty);
+    var element = transform.element;
+    expect(element.components, ['m', 'E']);
+    expect(element.isStatic, isTrue);
   }
 
   void test_element_variable() {
diff --git a/pkg/analysis_server/test/src/services/correction/fix/fix_processor.dart b/pkg/analysis_server/test/src/services/correction/fix/fix_processor.dart
index 50411cb..fc0eaa0 100644
--- a/pkg/analysis_server/test/src/services/correction/fix/fix_processor.dart
+++ b/pkg/analysis_server/test/src/services/correction/fix/fix_processor.dart
@@ -3,13 +3,10 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:analysis_server/plugin/edit/fix/fix_core.dart';
-import 'package:analysis_server/src/services/completion/dart/extension_cache.dart';
 import 'package:analysis_server/src/services/correction/bulk_fix_processor.dart';
 import 'package:analysis_server/src/services/correction/change_workspace.dart';
 import 'package:analysis_server/src/services/correction/fix.dart';
-import 'package:analysis_server/src/services/correction/fix/dart/top_level_declarations.dart';
 import 'package:analysis_server/src/services/correction/fix_internal.dart';
-import 'package:analyzer/dart/analysis/results.dart';
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/src/dart/analysis/byte_store.dart';
 import 'package:analyzer/src/dart/error/lint_codes.dart';
@@ -197,21 +194,11 @@
 
   /// Computes fixes for the given [error] in [testUnit].
   Future<List<Fix>> _computeFixes(AnalysisError error) async {
-    var analysisContext = contextFor(testFile);
-
-    var tracker = DeclarationsTracker(MemoryByteStore(), resourceProvider);
-    tracker.addContext(analysisContext);
-
     var context = DartFixContextImpl(
       TestInstrumentationService(),
       workspace,
       testAnalysisResult,
       error,
-      (name) {
-        var provider = TopLevelDeclarationsProvider(tracker);
-        provider.doTrackerWork();
-        return provider.get(analysisContext, testFile, name);
-      },
     );
 
     var fixes = await FixInFileProcessor(context).compute();
@@ -256,18 +243,9 @@
 
 /// A base class defining support for writing fix processor tests.
 abstract class FixProcessorTest extends BaseFixProcessorTest {
-  /// The extension cache used for test purposes.
-  ExtensionCache extensionCache = ExtensionCache();
-
   /// Return the kind of fixes being tested by this test class.
   FixKind get kind;
 
-  Future<void> addUnimportedFile(String filePath, String content) async {
-    addSource(filePath, content);
-    var result = await session.getResolvedUnit(convertPath(filePath));
-    extensionCache.cacheFromResult(result as ResolvedUnitResult);
-  }
-
   Future<void> assertHasFix(String expected,
       {bool Function(AnalysisError)? errorFilter,
       int? length,
@@ -518,23 +496,11 @@
 
   /// Computes fixes for the given [error] in [testUnit].
   Future<List<Fix>> _computeFixes(AnalysisError error) async {
-    var analysisContext = contextFor(testFile);
-
-    var tracker = DeclarationsTracker(MemoryByteStore(), resourceProvider);
-    tracker.addContext(analysisContext);
-    extensionCache.cacheFromResult(testAnalysisResult);
-
     var context = DartFixContextImpl(
       TestInstrumentationService(),
       workspace,
       testAnalysisResult,
       error,
-      (name) {
-        var provider = TopLevelDeclarationsProvider(tracker);
-        provider.doTrackerWork();
-        return provider.get(analysisContext, testFile, name);
-      },
-      extensionCache: extensionCache,
     );
     return await DartFixContributor().computeFixes(context);
   }
diff --git a/pkg/analysis_server/test/src/services/correction/fix/import_library_prefix_test.dart b/pkg/analysis_server/test/src/services/correction/fix/import_library_prefix_test.dart
index 8779367..3219e6e 100644
--- a/pkg/analysis_server/test/src/services/correction/fix/import_library_prefix_test.dart
+++ b/pkg/analysis_server/test/src/services/correction/fix/import_library_prefix_test.dart
@@ -21,57 +21,56 @@
 
   Future<void> test_withClass() async {
     await resolveTestCode('''
-import 'dart:collection' as pref;
-main() {
-  pref.HashMap? s = null;
-  LinkedHashMap? f = null;
-  print('\$s \$f');
-}
+import 'dart:collection' as prefix;
+
+void f(prefix.HashMap a, HashMap b) {}
 ''');
     await assertHasFix('''
-import 'dart:collection' as pref;
-main() {
-  pref.HashMap? s = null;
-  pref.LinkedHashMap? f = null;
-  print('\$s \$f');
-}
+import 'dart:collection' as prefix;
+
+void f(prefix.HashMap a, prefix.HashMap b) {}
 ''');
   }
 
   Future<void> test_withExtension() async {
-    addSource('$testPackageLibPath/lib.dart', '''
-class C {}
+    addSource('$testPackageLibPath/a.dart', '''
 extension E on int {
-  static String m() => '';
+  static int foo() => 0;
 }
 ''');
     await resolveTestCode('''
-import 'lib.dart' as p;
-void f(p.C c) {
-  print(E.m());
+import 'a.dart' as prefix;
+
+void f() {
+  prefix.E.foo();
+  E.foo();
 }
 ''');
     await assertHasFix('''
-import 'lib.dart' as p;
-void f(p.C c) {
-  print(p.E.m());
+import 'a.dart' as prefix;
+
+void f() {
+  prefix.E.foo();
+  prefix.E.foo();
 }
 ''');
   }
 
   Future<void> test_withTopLevelVariable() async {
     await resolveTestCode('''
-import 'dart:math' as pref;
-main() {
-  print(pref.e);
-  print(pi);
+import 'dart:math' as prefix;
+
+void f() {
+  prefix.e;
+  pi;
 }
 ''');
     await assertHasFix('''
-import 'dart:math' as pref;
-main() {
-  print(pref.e);
-  print(pref.pi);
+import 'dart:math' as prefix;
+
+void f() {
+  prefix.e;
+  prefix.pi;
 }
 ''');
   }
diff --git a/pkg/analysis_server/test/src/services/correction/fix/import_library_project_test.dart b/pkg/analysis_server/test/src/services/correction/fix/import_library_project_test.dart
index a677f3a..75e8a94 100644
--- a/pkg/analysis_server/test/src/services/correction/fix/import_library_project_test.dart
+++ b/pkg/analysis_server/test/src/services/correction/fix/import_library_project_test.dart
@@ -40,7 +40,7 @@
   }
 
   Future<void> test_extension_notImported_field_onThisType_fromClass() async {
-    addUnimportedFile('$testPackageLibPath/lib2.dart', '''
+    addSource('$testPackageLibPath/lib2.dart', '''
 import 'package:test/lib1.dart';
 
 extension E on C {
@@ -68,7 +68,7 @@
   }
 
   Future<void> test_extension_notImported_getter() async {
-    addUnimportedFile('$testPackageLibPath/lib.dart', '''
+    addSource('$testPackageLibPath/lib.dart', '''
 extension E on String {
   int get m => 0;
 }
@@ -88,7 +88,7 @@
   }
 
   Future<void> test_extension_notImported_method() async {
-    addUnimportedFile('$testPackageLibPath/lib.dart', '''
+    addSource('$testPackageLibPath/lib.dart', '''
 extension E on String {
   void m() {}
 }
@@ -108,7 +108,7 @@
   }
 
   Future<void> test_extension_notImported_method_extendsGeneric() async {
-    addUnimportedFile('$testPackageLibPath/lib.dart', '''
+    addSource('$testPackageLibPath/lib.dart', '''
 import 'package:test/lib1.dart';
 
 extension E<T extends num> on List<T> {
@@ -130,7 +130,7 @@
   }
 
   Future<void> test_extension_notImported_method_onThisType_fromClass() async {
-    addUnimportedFile('$testPackageLibPath/lib2.dart', '''
+    addSource('$testPackageLibPath/lib2.dart', '''
 import 'package:test/lib1.dart';
 
 extension E on C {
@@ -163,7 +163,7 @@
 
   Future<void>
       test_extension_notImported_method_onThisType_fromExtension() async {
-    addUnimportedFile('$testPackageLibPath/lib2.dart', '''
+    addSource('$testPackageLibPath/lib2.dart', '''
 import 'package:test/lib1.dart';
 
 extension E on C {
@@ -195,7 +195,7 @@
   }
 
   Future<void> test_extension_notImported_operator() async {
-    addUnimportedFile('$testPackageLibPath/lib.dart', '''
+    addSource('$testPackageLibPath/lib.dart', '''
 extension E on String {
   String operator -(String other) => this;
 }
@@ -215,7 +215,7 @@
   }
 
   Future<void> test_extension_notImported_setter() async {
-    addUnimportedFile('$testPackageLibPath/lib.dart', '''
+    addSource('$testPackageLibPath/lib.dart', '''
 extension E on String {
   set m(int v) {}
 }
@@ -234,6 +234,44 @@
 ''');
   }
 
+  Future<void> test_extension_otherPackage_exported_fromSrc() async {
+    var pkgRootPath = '$packagesRootPath/aaa';
+
+    newFile('$pkgRootPath/lib/a.dart', content: r'''
+export 'src/b.dart';
+''');
+
+    newFile('$pkgRootPath/lib/src/b.dart', content: r'''
+extension IntExtension on int {
+  int get foo => 0;
+}
+''');
+
+    writeTestPackageConfig(
+      config: PackageConfigFileBuilder()
+        ..add(name: 'aaa', rootPath: pkgRootPath),
+    );
+
+    updateTestPubspecFile('''
+dependencies:
+  aaa: any
+''');
+
+    await resolveTestCode('''
+void f() {
+  0.foo;
+}
+''');
+
+    await assertHasFix('''
+import 'package:aaa/a.dart';
+
+void f() {
+  0.foo;
+}
+''');
+  }
+
   Future<void> test_invalidUri_interpolation() async {
     addSource('$testPackageLibPath/lib.dart', r'''
 class Test {
@@ -261,11 +299,13 @@
   }
 
   Future<void> test_lib() async {
-    newFile('/.pub-cache/my_pkg/lib/a.dart', content: 'class Test {}');
+    newFile('$packagesRootPath/my_pkg/lib/a.dart', content: '''
+class Test {}
+''');
 
     writeTestPackageConfig(
       config: PackageConfigFileBuilder()
-        ..add(name: 'my_pkg', rootPath: '/.pub-cache/my_pkg'),
+        ..add(name: 'my_pkg', rootPath: '$packagesRootPath/my_pkg'),
     );
 
     newPubspecYamlFile('/home/test', r'''
@@ -291,7 +331,7 @@
   }
 
   Future<void> test_lib_extension() async {
-    newFile('/.pub-cache/my_pkg/lib/a.dart', content: '''
+    newFile('$packagesRootPath/my_pkg/lib/a.dart', content: '''
 extension E on int {
   static String m() => '';
 }
@@ -299,7 +339,7 @@
 
     writeTestPackageConfig(
       config: PackageConfigFileBuilder()
-        ..add(name: 'my_pkg', rootPath: '/.pub-cache/my_pkg'),
+        ..add(name: 'my_pkg', rootPath: '$packagesRootPath/my_pkg'),
     );
 
     newPubspecYamlFile('/home/test', r'''
@@ -323,11 +363,13 @@
   }
 
   Future<void> test_lib_src() async {
-    newFile('/.pub-cache/my_pkg/lib/src/a.dart', content: 'class Test {}');
+    newFile('$packagesRootPath/my_pkg/lib/src/a.dart', content: '''
+class Test {}
+''');
 
     writeTestPackageConfig(
       config: PackageConfigFileBuilder()
-        ..add(name: 'my_pkg', rootPath: '/.pub-cache/my_pkg'),
+        ..add(name: 'my_pkg', rootPath: '$packagesRootPath/my_pkg'),
     );
 
     newPubspecYamlFile('/home/test', r'''
@@ -344,7 +386,9 @@
   }
 
   Future<void> test_notInLib() async {
-    addSource('/home/other/test/lib.dart', 'class Test {}');
+    addSource('/home/other/test/lib.dart', '''
+class Test {}
+''');
     await resolveTestCode('''
 main() {
   Test t;
@@ -672,6 +716,224 @@
 ''');
   }
 
+  Future<void> test_withClass_pub_other_inLib_dependencies() async {
+    var aaaRoot = getFolder('$packagesRootPath/aaa');
+    newFile('${aaaRoot.path}/lib/a.dart', content: '''
+class Test {}
+''');
+
+    updateTestPubspecFile(r'''
+name: test
+dependencies:
+  aaa: any
+''');
+
+    writeTestPackageConfig(
+      config: PackageConfigFileBuilder()
+        ..add(name: 'aaa', rootPath: aaaRoot.path),
+    );
+
+    await resolveTestCode('''
+void f(Test t) {}
+''');
+
+    await assertHasFix('''
+import 'package:aaa/a.dart';
+
+void f(Test t) {}
+''');
+  }
+
+  Future<void> test_withClass_pub_other_inLib_devDependencies() async {
+    var aaaRoot = getFolder('$packagesRootPath/aaa');
+    newFile('${aaaRoot.path}/lib/a.dart', content: '''
+class Test {}
+''');
+
+    updateTestPubspecFile(r'''
+name: test
+dev_dependencies:
+  aaa: any
+''');
+
+    writeTestPackageConfig(
+      config: PackageConfigFileBuilder()
+        ..add(name: 'aaa', rootPath: aaaRoot.path),
+    );
+
+    await resolveTestCode('''
+void f(Test t) {}
+''');
+
+    await assertNoFix();
+  }
+
+  Future<void> test_withClass_pub_other_inLib_notListed() async {
+    var aaaRoot = getFolder('$packagesRootPath/aaa');
+    newFile('${aaaRoot.path}/lib/a.dart', content: '''
+class Test {}
+''');
+
+    updateTestPubspecFile(r'''
+name: test
+''');
+
+    writeTestPackageConfig(
+      config: PackageConfigFileBuilder()
+        ..add(name: 'aaa', rootPath: aaaRoot.path),
+    );
+
+    await resolveTestCode('''
+void f(Test t) {}
+''');
+
+    // If `aaa` is not in `dependencies`, we will not suggest it.
+    await assertNoFix();
+  }
+
+  Future<void> test_withClass_pub_other_inTest_dependencies() async {
+    var aaaRoot = getFolder('$packagesRootPath/aaa');
+    newFile('${aaaRoot.path}/lib/a.dart', content: '''
+class Test {}
+''');
+
+    updateTestPubspecFile(r'''
+name: test
+dependencies:
+  aaa: any
+''');
+
+    writeTestPackageConfig(
+      config: PackageConfigFileBuilder()
+        ..add(name: 'aaa', rootPath: aaaRoot.path),
+    );
+
+    var b = newFile('$testPackageTestPath/b.dart', content: r'''
+void f(Test t) {}
+''');
+
+    await resolveFile2(b.path);
+
+    await assertHasFix('''
+import 'package:aaa/a.dart';
+
+void f(Test t) {}
+''', target: b.path);
+  }
+
+  Future<void> test_withClass_pub_other_inTest_devDependencies() async {
+    var aaaRoot = getFolder('$packagesRootPath/aaa');
+    newFile('${aaaRoot.path}/lib/a.dart', content: '''
+class Test {}
+''');
+
+    updateTestPubspecFile(r'''
+name: test
+dev_dependencies:
+  aaa: any
+''');
+
+    writeTestPackageConfig(
+      config: PackageConfigFileBuilder()
+        ..add(name: 'aaa', rootPath: aaaRoot.path),
+    );
+
+    var b = newFile('$testPackageTestPath/b.dart', content: r'''
+void f(Test t) {}
+''');
+
+    await resolveFile2(b.path);
+
+    await assertHasFix('''
+import 'package:aaa/a.dart';
+
+void f(Test t) {}
+''', target: b.path);
+  }
+
+  Future<void> test_withClass_pub_this() async {
+    updateTestPubspecFile(r'''
+name: test
+''');
+
+    newFile('$testPackageLibPath/a.dart', content: r'''
+class Test {}
+''');
+
+    await resolveTestCode('''
+void f(Test t) {}
+''');
+
+    await assertHasFix('''
+import 'package:test/a.dart';
+
+void f(Test t) {}
+''');
+  }
+
+  Future<void> test_withClass_pub_this_inLib_excludesTest() async {
+    updateTestPubspecFile(r'''
+name: test
+''');
+
+    newFile('$testPackageTestPath/a.dart', content: r'''
+class Test {}
+''');
+
+    await resolveTestCode('''
+void f(Test t) {}
+''');
+    await assertNoFix();
+  }
+
+  Future<void> test_withClass_pub_this_inTest_includesTest() async {
+    updateTestPubspecFile(r'''
+name: test
+''');
+
+    newFile('$testPackageTestPath/a.dart', content: r'''
+class Test {}
+''');
+
+    var b = newFile('$testPackageTestPath/b.dart', content: r'''
+void f(Test t) {}
+''');
+
+    await resolveFile2(b.path);
+
+    await assertHasFix('''
+import 'a.dart';
+
+void f(Test t) {}
+''', target: b.path);
+  }
+
+  Future<void> test_withExtension_pub_this() async {
+    updateTestPubspecFile(r'''
+name: test
+''');
+
+    newFile('$testPackageLibPath/a.dart', content: r'''
+extension IntExtension on int {
+  int get foo => 0;
+}
+''');
+
+    await resolveTestCode('''
+void f() {
+  IntExtension(0).foo;
+}
+''');
+
+    await assertHasFix('''
+import 'package:test/a.dart';
+
+void f() {
+  IntExtension(0).foo;
+}
+''');
+  }
+
   Future<void> test_withFunction() async {
     addSource('$testPackageLibPath/lib.dart', '''
 library lib;
@@ -692,7 +954,9 @@
   }
 
   Future<void> test_withFunction_functionTopLevelVariable() async {
-    addSource('$testPackageLibPath/lib.dart', 'var myFunction = () {};');
+    addSource('$testPackageLibPath/lib.dart', '''
+var myFunction = () {};
+''');
     await resolveTestCode('''
 main() {
   myFunction();
@@ -708,7 +972,9 @@
   }
 
   Future<void> test_withFunction_functionTopLevelVariableIdentifier() async {
-    addSource('$testPackageLibPath/lib.dart', 'var myFunction = () {};');
+    addSource('$testPackageLibPath/lib.dart', '''
+var myFunction = () {};
+''');
     await resolveTestCode('''
 main() {
   myFunction;
@@ -744,7 +1010,9 @@
 
   @failingTest
   Future<void> test_withFunction_nonFunctionType() async {
-    addSource('$testPackageLibPath/lib.dart', 'int zero = 0;');
+    addSource('$testPackageLibPath/lib.dart', '''
+int zero = 0;
+''');
     await resolveTestCode('''
 main() {
   zero();
@@ -797,6 +1065,67 @@
 ''');
   }
 
+  Future<void> test_withGetter_read() async {
+    addSource('$testPackageLibPath/a.dart', '''
+int get foo => 0;
+''');
+
+    await resolveTestCode('''
+void f() {
+  foo;
+}
+''');
+
+    await assertHasFix('''
+import 'package:test/a.dart';
+
+void f() {
+  foo;
+}
+''');
+  }
+
+  Future<void> test_withGetter_readWrite() async {
+    addSource('$testPackageLibPath/a.dart', '''
+int get foo => 0;
+''');
+
+    await resolveTestCode('''
+void f() {
+  foo++;
+}
+''');
+
+    await assertHasFix('''
+import 'package:test/a.dart';
+
+void f() {
+  foo++;
+}
+''');
+  }
+
+  /// Not really useful, but shows what we have.
+  Future<void> test_withGetter_write() async {
+    addSource('$testPackageLibPath/a.dart', '''
+int get foo => 0;
+''');
+
+    await resolveTestCode('''
+void f() {
+  foo = 0;
+}
+''');
+
+    await assertHasFix('''
+import 'package:test/a.dart';
+
+void f() {
+  foo = 0;
+}
+''');
+  }
+
   Future<void> test_withMixin() async {
     addSource('$testPackageLibPath/lib.dart', '''
 mixin Test {}
@@ -811,21 +1140,80 @@
 ''');
   }
 
-  Future<void> test_withTopLevelVariable() async {
-    addSource('$testPackageLibPath/lib.dart', '''
-library lib;
-int MY_VAR = 42;
+  Future<void> test_withSetter_assignment() async {
+    addSource('$testPackageLibPath/a.dart', '''
+set foo(int _) {}
 ''');
+
     await resolveTestCode('''
-main() {
-  print(MY_VAR);
+void f() {
+  foo = 0;
 }
 ''');
-    await assertHasFix('''
-import 'package:test/lib.dart';
 
-main() {
-  print(MY_VAR);
+    await assertHasFix('''
+import 'package:test/a.dart';
+
+void f() {
+  foo = 0;
+}
+''');
+  }
+
+  Future<void> test_withTopLevelVariable_annotation() async {
+    addSource('$testPackageLibPath/a.dart', '''
+const foo = 0;
+''');
+
+    await resolveTestCode('''
+@foo
+void f() {}
+''');
+
+    await assertHasFix('''
+import 'package:test/a.dart';
+
+@foo
+void f() {}
+''');
+  }
+
+  Future<void> test_withTopLevelVariable_read() async {
+    addSource('$testPackageLibPath/a.dart', '''
+var foo = 0;
+''');
+
+    await resolveTestCode('''
+void f() {
+  foo;
+}
+''');
+
+    await assertHasFix('''
+import 'package:test/a.dart';
+
+void f() {
+  foo;
+}
+''');
+  }
+
+  Future<void> test_withTopLevelVariable_write() async {
+    addSource('$testPackageLibPath/a.dart', '''
+var foo = 0;
+''');
+
+    await resolveTestCode('''
+void f() {
+  foo = 0;
+}
+''');
+
+    await assertHasFix('''
+import 'package:test/a.dart';
+
+void f() {
+  foo = 0;
 }
 ''');
   }
@@ -837,12 +1225,16 @@
   FixKind get kind => DartFixKind.IMPORT_LIBRARY_PROJECT2;
 
   Future<void> test_lib() async {
-    newFile('/.pub-cache/my_pkg/lib/a.dart', content: "export 'b.dart';");
-    newFile('/.pub-cache/my_pkg/lib/b.dart', content: 'class Test {}');
+    newFile('$packagesRootPath/my_pkg/lib/a.dart', content: '''
+export 'b.dart';
+''');
+    newFile('$packagesRootPath/my_pkg/lib/b.dart', content: '''
+class Test {}
+''');
 
     writeTestPackageConfig(
       config: PackageConfigFileBuilder()
-        ..add(name: 'my_pkg', rootPath: '/.pub-cache/my_pkg'),
+        ..add(name: 'my_pkg', rootPath: '$packagesRootPath/my_pkg'),
     );
 
     newPubspecYamlFile('/home/test', r'''
@@ -866,12 +1258,16 @@
   }
 
   Future<void> test_lib_src() async {
-    newFile('/.pub-cache/my_pkg/lib/a.dart', content: "export 'src/b.dart';");
-    newFile('/.pub-cache/my_pkg/lib/src/b.dart', content: 'class Test {}');
+    newFile('$packagesRootPath/my_pkg/lib/a.dart', content: '''
+export 'src/b.dart';
+''');
+    newFile('$packagesRootPath/my_pkg/lib/src/b.dart', content: '''
+class Test {}
+''');
 
     writeTestPackageConfig(
       config: PackageConfigFileBuilder()
-        ..add(name: 'my_pkg', rootPath: '/.pub-cache/my_pkg'),
+        ..add(name: 'my_pkg', rootPath: '$packagesRootPath/my_pkg'),
     );
 
     newPubspecYamlFile('/home/test', r'''
@@ -895,8 +1291,10 @@
   }
 
   Future<void> test_lib_src_extension() async {
-    newFile('/.pub-cache/my_pkg/lib/a.dart', content: "export 'src/b.dart';");
-    newFile('/.pub-cache/my_pkg/lib/src/b.dart', content: '''
+    newFile('$packagesRootPath/my_pkg/lib/a.dart', content: '''
+export 'src/b.dart';
+''');
+    newFile('$packagesRootPath/my_pkg/lib/src/b.dart', content: '''
 extension E on int {
   static String m() => '';
 }
@@ -904,7 +1302,7 @@
 
     writeTestPackageConfig(
       config: PackageConfigFileBuilder()
-        ..add(name: 'my_pkg', rootPath: '/.pub-cache/my_pkg'),
+        ..add(name: 'my_pkg', rootPath: '$packagesRootPath/my_pkg'),
     );
 
     newPubspecYamlFile('/home/test', r'''
@@ -931,47 +1329,6 @@
   @override
   FixKind get kind => DartFixKind.IMPORT_LIBRARY_PROJECT3;
 
-  Future<void> test_inLibSrc_differentContextRoot() async {
-    newFile('/.pub-cache/bbb/lib/b1.dart', content: r'''
-import 'src/b2.dart';
-class A {}
-''');
-
-    writeTestPackageConfig(
-      config: PackageConfigFileBuilder()
-        ..add(name: 'bbb', rootPath: '/.pub-cache/bbb'),
-    );
-
-    newFile('/.pub-cache/bbb/lib/src/b2.dart', content: 'class Test {}');
-    await resolveTestCode('''
-import 'package:bbb/b1.dart';
-main() {
-  Test t;
-  A? a;
-  print('\$t \$a');
-}
-''');
-    await assertNoFix();
-  }
-
-  Future<void> test_inLibSrc_thisContextRoot() async {
-    addSource('$testPackageLibPath/src/lib.dart', 'class Test {}');
-    await resolveTestCode('''
-main() {
-  Test t;
-  print(t);
-}
-''');
-    await assertHasFix('''
-import 'package:test/src/lib.dart';
-
-main() {
-  Test t;
-  print(t);
-}
-''');
-  }
-
   Future<void> test_inLibSrc_thisContextRoot_extension() async {
     addSource('$testPackageLibPath/src/lib.dart', '''
 extension E on int {
@@ -991,4 +1348,46 @@
 }
 ''');
   }
+
+  Future<void> test_withClass_pub_this_inLib_includesThisSrc() async {
+    updateTestPubspecFile(r'''
+name: test
+''');
+
+    newFile('$testPackageLibPath/src/a.dart', content: r'''
+class Test {}
+''');
+
+    await resolveTestCode('''
+void f(Test t) {}
+''');
+
+    await assertHasFix('''
+import 'package:test/src/a.dart';
+
+void f(Test t) {}
+''');
+  }
+
+  Future<void> test_withClass_pub_this_inTest_includesThisSrc() async {
+    updateTestPubspecFile(r'''
+name: test
+''');
+
+    newFile('$testPackageLibPath/src/a.dart', content: r'''
+class Test {}
+''');
+
+    var b = newFile('$testPackageTestPath/b.dart', content: r'''
+void f(Test t) {}
+''');
+
+    await resolveFile2(b.path);
+
+    await assertHasFix('''
+import 'package:test/src/a.dart';
+
+void f(Test t) {}
+''', target: b.path);
+  }
 }
diff --git a/pkg/analysis_server/test/src/services/correction/fix/replace_return_type_future_test.dart b/pkg/analysis_server/test/src/services/correction/fix/replace_return_type_future_test.dart
index 9cfafa7..818dad5 100644
--- a/pkg/analysis_server/test/src/services/correction/fix/replace_return_type_future_test.dart
+++ b/pkg/analysis_server/test/src/services/correction/fix/replace_return_type_future_test.dart
@@ -20,38 +20,14 @@
   @override
   FixKind get kind => DartFixKind.REPLACE_RETURN_TYPE_FUTURE;
 
-  Future<void> test_adjacentNodes_withImport() async {
-    await resolveTestCode('''
-import 'dart:async';
-var v;int main() async => 0;
-''');
-    await assertHasFix('''
-import 'dart:async';
-var v;Future<int> main() async => 0;
-''', errorFilter: (error) {
-      return error.errorCode == CompileTimeErrorCode.ILLEGAL_ASYNC_RETURN_TYPE;
-    });
-  }
-
-  Future<void> test_adjacentNodes_withoutImport() async {
-    await resolveTestCode('''
-var v;int main() async => 0;
-''');
-    await assertHasFix('''
-var v;Future<int> main() async => 0;
-''');
-  }
-
   Future<void> test_complexTypeName_withImport() async {
     await resolveTestCode('''
 import 'dart:async';
-List<int> main() async {
-}
+List<int> f() async {}
 ''');
     await assertHasFix('''
 import 'dart:async';
-Future<List<int>> main() async {
-}
+Future<List<int>> f() async {}
 ''', errorFilter: (error) {
       return error.errorCode == CompileTimeErrorCode.ILLEGAL_ASYNC_RETURN_TYPE;
     });
@@ -59,25 +35,21 @@
 
   Future<void> test_complexTypeName_withoutImport() async {
     await resolveTestCode('''
-List<int> main() async {
-}
+List<int> f() async {}
 ''');
     await assertHasFix('''
-Future<List<int>> main() async {
-}
+Future<List<int>> f() async {}
 ''');
   }
 
   Future<void> test_importedWithPrefix() async {
     await resolveTestCode('''
 import 'dart:async' as al;
-int main() async {
-}
+int f() async {}
 ''');
     await assertHasFix('''
 import 'dart:async' as al;
-al.Future<int> main() async {
-}
+al.Future<int> f() async {}
 ''', errorFilter: (error) {
       return error.errorCode == CompileTimeErrorCode.ILLEGAL_ASYNC_RETURN_TYPE;
     });
@@ -86,11 +58,11 @@
   Future<void> test_simpleTypeName_withImport() async {
     await resolveTestCode('''
 import 'dart:async';
-int main() async => 0;
+int f() async {}
 ''');
     await assertHasFix('''
 import 'dart:async';
-Future<int> main() async => 0;
+Future<int> f() async {}
 ''', errorFilter: (error) {
       return error.errorCode == CompileTimeErrorCode.ILLEGAL_ASYNC_RETURN_TYPE;
     });
@@ -98,40 +70,10 @@
 
   Future<void> test_simpleTypeName_withoutImport() async {
     await resolveTestCode('''
-int main() async => 0;
+int f() async {}
 ''');
     await assertHasFix('''
-Future<int> main() async => 0;
-''');
-  }
-
-  Future<void> test_withLibraryDirective_withImport() async {
-    await resolveTestCode('''
-library main;
-import 'dart:async';
-int main() async {
-}
-''');
-    await assertHasFix('''
-library main;
-import 'dart:async';
-Future<int> main() async {
-}
-''', errorFilter: (error) {
-      return error.errorCode == CompileTimeErrorCode.ILLEGAL_ASYNC_RETURN_TYPE;
-    });
-  }
-
-  Future<void> test_withLibraryDirective_withoutImport() async {
-    await resolveTestCode('''
-library main;
-int main() async {
-}
-''');
-    await assertHasFix('''
-library main;
-Future<int> main() async {
-}
+Future<int> f() async {}
 ''');
   }
 }
diff --git a/pkg/analysis_server/test/src/services/correction/fix/replace_return_type_iterable_test.dart b/pkg/analysis_server/test/src/services/correction/fix/replace_return_type_iterable_test.dart
new file mode 100644
index 0000000..e83a01c
--- /dev/null
+++ b/pkg/analysis_server/test/src/services/correction/fix/replace_return_type_iterable_test.dart
@@ -0,0 +1,50 @@
+// Copyright (c) 2018, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analysis_server/src/services/correction/fix.dart';
+import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import 'fix_processor.dart';
+
+void main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(ReplaceReturnTypeIterableTest);
+  });
+}
+
+@reflectiveTest
+class ReplaceReturnTypeIterableTest extends FixProcessorTest {
+  @override
+  FixKind get kind => DartFixKind.REPLACE_RETURN_TYPE_ITERABLE;
+
+  Future<void> test_complexTypeName() async {
+    await resolveTestCode('''
+List<int> f() sync* {}
+''');
+    await assertHasFix('''
+Iterable<List<int>> f() sync* {}
+''');
+  }
+
+  Future<void> test_importedWithPrefix() async {
+    await resolveTestCode('''
+import 'dart:core' as c;
+c.int f() sync* {}
+''');
+    await assertHasFix('''
+import 'dart:core' as c;
+c.Iterable<c.int> f() sync* {}
+''');
+  }
+
+  Future<void> test_simpleTypeName() async {
+    await resolveTestCode('''
+int f() sync* {}
+''');
+    await assertHasFix('''
+Iterable<int> f() sync* {}
+''');
+  }
+}
diff --git a/pkg/analysis_server/test/src/services/correction/fix/replace_return_type_stream_test.dart b/pkg/analysis_server/test/src/services/correction/fix/replace_return_type_stream_test.dart
new file mode 100644
index 0000000..e564385
--- /dev/null
+++ b/pkg/analysis_server/test/src/services/correction/fix/replace_return_type_stream_test.dart
@@ -0,0 +1,82 @@
+// Copyright (c) 2018, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analysis_server/src/services/correction/fix.dart';
+import 'package:analyzer/src/error/codes.dart';
+import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import 'fix_processor.dart';
+
+void main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(ReplaceReturnTypeStreamTest);
+  });
+}
+
+@reflectiveTest
+class ReplaceReturnTypeStreamTest extends FixProcessorTest {
+  @override
+  FixKind get kind => DartFixKind.REPLACE_RETURN_TYPE_STREAM;
+
+  Future<void> test_complexTypeName_withImport() async {
+    await resolveTestCode('''
+import 'dart:async';
+List<int> f() async* {}
+''');
+    await assertHasFix('''
+import 'dart:async';
+Stream<List<int>> f() async* {}
+''', errorFilter: (error) {
+      return error.errorCode ==
+          CompileTimeErrorCode.ILLEGAL_ASYNC_GENERATOR_RETURN_TYPE;
+    });
+  }
+
+  Future<void> test_complexTypeName_withoutImport() async {
+    await resolveTestCode('''
+List<int> f() async* {}
+''');
+    await assertHasFix('''
+Stream<List<int>> f() async* {}
+''');
+  }
+
+  Future<void> test_importedWithPrefix() async {
+    await resolveTestCode('''
+import 'dart:async' as al;
+int f() async* {}
+''');
+    await assertHasFix('''
+import 'dart:async' as al;
+al.Stream<int> f() async* {}
+''', errorFilter: (error) {
+      return error.errorCode ==
+          CompileTimeErrorCode.ILLEGAL_ASYNC_GENERATOR_RETURN_TYPE;
+    });
+  }
+
+  Future<void> test_simpleTypeName_withImport() async {
+    await resolveTestCode('''
+import 'dart:async';
+int f() async* {}
+''');
+    await assertHasFix('''
+import 'dart:async';
+Stream<int> f() async* {}
+''', errorFilter: (error) {
+      return error.errorCode ==
+          CompileTimeErrorCode.ILLEGAL_ASYNC_GENERATOR_RETURN_TYPE;
+    });
+  }
+
+  Future<void> test_simpleTypeName_withoutImport() async {
+    await resolveTestCode('''
+int f() async* {}
+''');
+    await assertHasFix('''
+Stream<int> f() async* {}
+''');
+  }
+}
diff --git a/pkg/analysis_server/test/src/services/correction/fix/test_all.dart b/pkg/analysis_server/test/src/services/correction/fix/test_all.dart
index 3753bfb..3174635 100644
--- a/pkg/analysis_server/test/src/services/correction/fix/test_all.dart
+++ b/pkg/analysis_server/test/src/services/correction/fix/test_all.dart
@@ -30,6 +30,7 @@
 import 'add_null_check_test.dart' as add_null_check;
 import 'add_override_test.dart' as add_override;
 import 'add_required_test.dart' as add_required;
+import 'add_return_null_test.dart' as add_return_null;
 import 'add_return_type_test.dart' as add_return_type;
 import 'add_static_test.dart' as add_static;
 import 'add_super_constructor_invocation_test.dart'
@@ -183,6 +184,8 @@
 import 'replace_new_with_const_test.dart' as replace_new_with_const;
 import 'replace_null_with_closure_test.dart' as replace_null_with_closure;
 import 'replace_return_type_future_test.dart' as replace_return_type_future;
+import 'replace_return_type_iterable_test.dart' as replace_return_type_iterable;
+import 'replace_return_type_stream_test.dart' as replace_return_type_stream;
 import 'replace_return_type_test.dart' as replace_return_type;
 import 'replace_var_with_dynamic_test.dart' as replace_var_with_dynamic;
 import 'replace_with_brackets_test.dart' as replace_with_brackets;
@@ -234,6 +237,7 @@
     add_null_check.main();
     add_override.main();
     add_required.main();
+    add_return_null.main();
     add_return_type.main();
     add_static.main();
     add_super_constructor_invocation.main();
@@ -370,6 +374,8 @@
     replace_null_with_void.main();
     replace_return_type.main();
     replace_return_type_future.main();
+    replace_return_type_iterable.main();
+    replace_return_type_stream.main();
     replace_var_with_dynamic.main();
     replace_with_brackets.main();
     replace_with_conditional_assignment.main();
diff --git a/pkg/analysis_server/test/src/utilities/extensions/range_factory_test.dart b/pkg/analysis_server/test/src/utilities/extensions/range_factory_test.dart
index d4bf8fd..e8d35e3 100644
--- a/pkg/analysis_server/test/src/utilities/extensions/range_factory_test.dart
+++ b/pkg/analysis_server/test/src/utilities/extensions/range_factory_test.dart
@@ -15,6 +15,7 @@
   defineReflectiveSuite(() {
     defineReflectiveTests(RangeFactory_NodeInListTest);
     defineReflectiveTests(RangeFactory_NodeInListWithCommentsTest);
+    defineReflectiveTests(RangeFactory_NodeWithCommentsTest);
   });
 }
 
@@ -26,11 +27,54 @@
     return invocation.argumentList.arguments;
   }
 
-  void _assertRange(int index, SourceRange expectedRange) {
+  void _assertArgumentRange(int index, SourceRange expectedRange) {
     var list = _argumentList;
     expect(range.nodeInListWithComments(testUnit.lineInfo!, list, list[index]),
         expectedRange);
   }
+
+  void _assertClassMemberRanges(Map<int, SourceRange> expectedRanges) {
+    var class_ = findNode.classDeclaration('class');
+    var list = class_.members;
+    for (var entry in expectedRanges.entries) {
+      expect(range.nodeWithComments(testUnit.lineInfo!, list[entry.key]),
+          entry.value);
+    }
+  }
+
+  void _assertUnitRanges(Map<int, SourceRange> expectedRanges) {
+    var list = testUnit.declarations;
+    for (var entry in expectedRanges.entries) {
+      expect(range.nodeWithComments(testUnit.lineInfo!, list[entry.key]),
+          entry.value);
+    }
+  }
+
+  /// Create a [SourceRange] for the positions start/end before the supplied
+  /// search strings.
+  SourceRange _range({
+    String? startsBefore,
+    String? startsAfter,
+    String? endsBefore,
+    String? endsAfter,
+  }) {
+    expect(startsBefore == null, isNot(startsAfter == null),
+        reason: 'Specify exactly one of startsBefore/startsAfter');
+    expect(endsBefore == null, isNot(endsAfter == null),
+        reason: 'Specify exactly one of endsBefore/endsAfter');
+
+    final offset = startsBefore != null
+        ? testCode.indexOf(startsBefore)
+        : testCode.indexOf(startsAfter!) + startsAfter.length;
+    final end = endsBefore != null
+        ? testCode.indexOf(endsBefore)
+        : testCode.indexOf(endsAfter!) + endsAfter.length;
+
+    expect(offset, greaterThanOrEqualTo(0));
+    expect(end, greaterThanOrEqualTo(0));
+
+    return SourceRange(offset, end - offset);
+  }
 }
 
 /// Copied from `analyzer_plugin/test/utilities/range_factory_test.dart` in
@@ -46,7 +90,7 @@
 }
 void g({int? a, int? b}) {}
 ''');
-    _assertRange(0, SourceRange(15, 6));
+    _assertArgumentRange(0, SourceRange(15, 6));
   }
 
   Future<void> test_argumentList_first_positional() async {
@@ -56,7 +100,7 @@
 }
 void g(int a, int b) {}
 ''');
-    _assertRange(0, SourceRange(15, 3));
+    _assertArgumentRange(0, SourceRange(15, 3));
   }
 
   Future<void> test_argumentList_last_named() async {
@@ -66,7 +110,7 @@
 }
 void g({int? a, int? b}) {}
 ''');
-    _assertRange(1, SourceRange(19, 6));
+    _assertArgumentRange(1, SourceRange(19, 6));
   }
 
   Future<void> test_argumentList_last_positional() async {
@@ -76,7 +120,7 @@
 }
 void g(int a, int b) {}
 ''');
-    _assertRange(1, SourceRange(16, 3));
+    _assertArgumentRange(1, SourceRange(16, 3));
   }
 
   Future<void> test_argumentList_middle_named() async {
@@ -86,7 +130,7 @@
 }
 void g({int? a, int? b, int? c}) {}
 ''');
-    _assertRange(1, SourceRange(19, 6));
+    _assertArgumentRange(1, SourceRange(19, 6));
   }
 
   Future<void> test_argumentList_middle_positional() async {
@@ -96,7 +140,7 @@
 }
 void g(int a, int b, int c) {}
 ''');
-    _assertRange(1, SourceRange(16, 3));
+    _assertArgumentRange(1, SourceRange(16, 3));
   }
 
   Future<void> test_argumentList_only_named() async {
@@ -106,7 +150,7 @@
 }
 void g({int? a}) {}
 ''');
-    _assertRange(0, SourceRange(15, 4));
+    _assertArgumentRange(0, SourceRange(15, 4));
   }
 
   Future<void> test_argumentList_only_named_trailingComma() async {
@@ -116,7 +160,7 @@
 }
 void g({int? a}) {}
 ''');
-    _assertRange(0, SourceRange(15, 5));
+    _assertArgumentRange(0, SourceRange(15, 5));
   }
 
   Future<void> test_argumentList_only_positional() async {
@@ -126,7 +170,7 @@
 }
 void g(int a) {}
 ''');
-    _assertRange(0, SourceRange(15, 1));
+    _assertArgumentRange(0, SourceRange(15, 1));
   }
 
   Future<void> test_argumentList_only_positional_trailingComma() async {
@@ -136,7 +180,7 @@
 }
 void g(int a) {}
 ''');
-    _assertRange(0, SourceRange(15, 2));
+    _assertArgumentRange(0, SourceRange(15, 2));
   }
 }
 
@@ -154,7 +198,7 @@
 }
 void g({int? a, int? b}) {}
 ''');
-    _assertRange(0, SourceRange(20, 36));
+    _assertArgumentRange(0, SourceRange(20, 36));
   }
 
   Future<void> test_argumentList_first_named_leadingComment() async {
@@ -169,7 +213,7 @@
 }
 void g({int? a, int? b}) {}
 ''');
-    _assertRange(0, SourceRange(20, 25));
+    _assertArgumentRange(0, SourceRange(20, 25));
   }
 
   Future<void> test_argumentList_first_named_trailingComment() async {
@@ -183,7 +227,7 @@
 }
 void g({int? a, int? b}) {}
 ''');
-    _assertRange(0, SourceRange(20, 21));
+    _assertArgumentRange(0, SourceRange(20, 21));
   }
 
   Future<void> test_argumentList_last_named_leadingAndTrailingComment() async {
@@ -197,7 +241,7 @@
 }
 void g({int? a, int? b}) {}
 ''');
-    _assertRange(1, SourceRange(36, 36));
+    _assertArgumentRange(1, SourceRange(36, 36));
   }
 
   Future<void> test_argumentList_last_named_leadingComment() async {
@@ -211,7 +255,7 @@
 }
 void g({int? a, int? b}) {}
 ''');
-    _assertRange(1, SourceRange(36, 25));
+    _assertArgumentRange(1, SourceRange(36, 25));
   }
 
   Future<void> test_argumentList_last_named_trailingComment() async {
@@ -224,7 +268,7 @@
 }
 void g({int? a, int? b}) {}
 ''');
-    _assertRange(1, SourceRange(36, 21));
+    _assertArgumentRange(1, SourceRange(36, 21));
   }
 
   Future<void>
@@ -239,7 +283,7 @@
 }
 void g({int? a, int? b}) {}
 ''');
-    _assertRange(1, SourceRange(36, 21));
+    _assertArgumentRange(1, SourceRange(36, 21));
   }
 
   Future<void>
@@ -256,7 +300,7 @@
 }
 void g({int? a, int? b, int? c}) {}
 ''');
-    _assertRange(1, SourceRange(36, 36));
+    _assertArgumentRange(1, SourceRange(36, 36));
   }
 
   Future<void> test_argumentList_middle_named_leadingComment() async {
@@ -272,7 +316,7 @@
 }
 void g({int? a, int? b, int? c}) {}
 ''');
-    _assertRange(1, SourceRange(36, 25));
+    _assertArgumentRange(1, SourceRange(36, 25));
   }
 
   Future<void> test_argumentList_middle_named_trailingComment() async {
@@ -287,7 +331,7 @@
 }
 void g({int? a, int? b, int? c}) {}
 ''');
-    _assertRange(1, SourceRange(36, 21));
+    _assertArgumentRange(1, SourceRange(36, 21));
   }
 
   Future<void>
@@ -302,7 +346,7 @@
 }
 void g({int? a, int? b, int? c}) {}
 ''');
-    _assertRange(1, SourceRange(25, 21));
+    _assertArgumentRange(1, SourceRange(25, 21));
   }
 
   Future<void> test_argumentList_only_named_leadingAndTrailingComment() async {
@@ -315,7 +359,7 @@
 }
 void g({int? a}) {}
 ''');
-    _assertRange(0, SourceRange(20, 31));
+    _assertArgumentRange(0, SourceRange(20, 31));
   }
 
   Future<void> test_argumentList_only_named_leadingComment() async {
@@ -328,7 +372,7 @@
 }
 void g({int? a}) {}
 ''');
-    _assertRange(0, SourceRange(20, 20));
+    _assertArgumentRange(0, SourceRange(20, 20));
   }
 
   Future<void> test_argumentList_only_named_trailingComment() async {
@@ -340,6 +384,501 @@
 }
 void g({int? a}) {}
 ''');
-    _assertRange(0, SourceRange(20, 16));
+    _assertArgumentRange(0, SourceRange(20, 16));
+  }
+}
+
+@reflectiveTest
+class RangeFactory_NodeWithCommentsTest extends BaseRangeFactoryTest {
+  Future<void> test_class_multiple_leading() async {
+    await resolveTestCode('''
+class A {
+  // 1
+  int foo = 1;
+  // 2
+  int bar = 2;
+}
+''');
+    _assertClassMemberRanges({
+      0: _range(startsBefore: '// 1', endsAfter: '= 1;'),
+      1: _range(startsBefore: '// 2', endsAfter: '= 2;'),
+    });
+  }
+
+  Future<void> test_class_multiple_leadingAndTrailing() async {
+    await resolveTestCode('''
+class A {
+  // 2
+  int foo = 1; // 3
+  // 4
+  int bar = 1; // 5
+}
+''');
+    _assertClassMemberRanges({
+      0: _range(startsBefore: '// 2', endsAfter: '// 3'),
+      1: _range(startsBefore: '// 4', endsAfter: '// 5'),
+    });
+  }
+
+  Future<void>
+      test_class_multiple_leadingAndTrailing_withClassBraceTrailing() async {
+    await resolveTestCode('''
+class A { // 1
+  // 2
+  int foo = 1; // 3
+  // 4
+  int bar = 1; // 5
+}
+''');
+    _assertClassMemberRanges({
+      0: _range(startsBefore: '// 2', endsAfter: '// 3'),
+      1: _range(startsBefore: '// 4', endsAfter: '// 5'),
+    });
+  }
+
+  Future<void> test_class_multiple_trailing() async {
+    await resolveTestCode('''
+class A {
+  int foo = 1; // 1
+  int bar = 2; // 2
+}
+''');
+    _assertClassMemberRanges({
+      0: _range(startsBefore: 'int foo', endsAfter: '// 1'),
+      1: _range(startsBefore: 'int bar', endsAfter: '// 2'),
+    });
+  }
+
+  Future<void> test_class_single_field_leading() async {
+    await resolveTestCode('''
+class A {
+  // 1
+  int foo = 1;
+}
+''');
+    _assertClassMemberRanges({
+      0: _range(startsBefore: '// 1', endsAfter: '= 1;'),
+    });
+  }
+
+  Future<void> test_class_single_field_leadingAndTrailing() async {
+    await resolveTestCode('''
+class A {
+  // 1
+  int foo = 1; // 2
+}
+''');
+    _assertClassMemberRanges({
+      0: _range(startsBefore: '// 1', endsAfter: '; // 2'),
+    });
+  }
+
+  Future<void>
+      test_class_single_field_leadingAndTrailing_withClassBraceTrailing() async {
+    await resolveTestCode('''
+class A { // 1
+  // 2
+  int foo = 1; // 3
+}
+''');
+    _assertClassMemberRanges({
+      0: _range(startsBefore: '// 2', endsAfter: '// 3'),
+    });
+  }
+
+  Future<void> test_class_single_field_trailing() async {
+    await resolveTestCode('''
+class A {
+  int foo = 1; // 1
+}
+''');
+    _assertClassMemberRanges({
+      0: _range(startsBefore: 'int foo', endsAfter: '// 1'),
+    });
+  }
+
+  Future<void> test_class_single_method_leading() async {
+    await resolveTestCode('''
+class A {
+  // 1
+  foo() {}
+}
+''');
+    _assertClassMemberRanges({
+      0: _range(startsBefore: '// 1', endsAfter: '{}'),
+    });
+  }
+
+  Future<void> test_class_single_method_leadingAndTrailing() async {
+    await resolveTestCode('''
+class A {
+  // foo
+  foo() {} // foo
+}
+''');
+    _assertClassMemberRanges({
+      0: _range(startsBefore: '// foo', endsAfter: '} // foo'),
+    });
+  }
+
+  Future<void>
+      test_class_single_method_leadingAndTrailing_withClassBraceTrailing() async {
+    await resolveTestCode('''
+class A { // 1
+  // 2
+  foo() {} // 3
+}
+''');
+    _assertClassMemberRanges({
+      0: _range(startsBefore: '// 2', endsAfter: '// 3'),
+    });
+  }
+
+  Future<void> test_class_single_method_trailing() async {
+    await resolveTestCode('''
+class A {
+  foo() {} // 1
+}
+''');
+    _assertClassMemberRanges({
+      0: _range(startsBefore: 'foo()', endsAfter: '// 1'),
+    });
+  }
+
+  Future<void> test_topLevel_fileHeader_dartDoc() async {
+    await resolveTestCode('''
+// Copyright (c) ...
+// ...
+
+/// 1
+int foo = 1; // 2
+
+/// 3
+int bar = 1; // 4
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '/// 1', endsAfter: '// 2'),
+      1: _range(startsBefore: '/// 3', endsAfter: '// 4'),
+    });
+  }
+
+  Future<void> test_topLevel_fileHeader_noDartDoc() async {
+    await resolveTestCode('''
+// Copyright (c) ...
+// ...
+
+int foo = 1; // 2
+
+int bar = 1; // 4
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: 'int foo', endsAfter: '// 2'),
+      1: _range(startsBefore: 'int bar', endsAfter: '// 4'),
+    });
+  }
+
+  Future<void> test_topLevel_languageVersion_dartDoc() async {
+    await resolveTestCode('''
+// @dart = 2.8
+
+/// 1
+int foo = 1; // 2
+
+/// 3
+int bar = 1; // 4
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '/// 1', endsAfter: '// 2'),
+      1: _range(startsBefore: '/// 3', endsAfter: '// 4'),
+    });
+  }
+
+  Future<void> test_topLevel_languageVersion_noDartDoc() async {
+    await resolveTestCode('''
+// @dart = 2.8
+
+int foo = 1; // 2
+
+int bar = 1; // 4
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: 'int foo', endsAfter: '// 2'),
+      1: _range(startsBefore: 'int bar', endsAfter: '// 4'),
+    });
+  }
+
+  Future<void> test_topLevel_multiple_leading() async {
+    await resolveTestCode('''
+import '';
+
+// 1
+int foo = 1;
+
+// 2
+int bar = 2;
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '// 1', endsAfter: '= 1;'),
+      1: _range(startsBefore: '// 2', endsAfter: '= 2;'),
+    });
+  }
+
+  Future<void> test_topLevel_multiple_leadingAndTrailing() async {
+    await resolveTestCode('''
+import '';
+
+// 2
+int foo = 1; // 3
+
+// 4
+int bar = 1; // 5
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '// 2', endsAfter: '// 3'),
+      1: _range(startsBefore: '// 4', endsAfter: '// 5'),
+    });
+  }
+
+  Future<void> test_topLevel_multiple_mixedComents() async {
+    await resolveTestCode('''
+import '';
+
+// 1
+// 2
+int foo = 1; // 3
+
+// 4
+// 5
+int bar = 1; // 6
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '// 1', endsAfter: '// 3'),
+      1: _range(startsBefore: '// 4', endsAfter: '// 6'),
+    });
+  }
+
+  Future<void> test_topLevel_multiple_trailing() async {
+    await resolveTestCode('''
+int foo = 1; // 1
+int bar = 2; // 2
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: 'int foo', endsAfter: '// 1'),
+      1: _range(startsBefore: 'int bar', endsAfter: '// 2'),
+    });
+  }
+
+  Future<void> test_topLevel_noTrailingNewline_leading() async {
+    await resolveTestCode('''
+import '';
+
+// 1
+int foo = 1;
+
+// 2
+int bar = 2;''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '// 1', endsAfter: '= 1;'),
+      1: _range(startsBefore: '// 2', endsAfter: '= 2;'),
+    });
+  }
+
+  Future<void> test_topLevel_noTrailingNewline_leadingAndTrailing() async {
+    await resolveTestCode('''
+import '';
+
+// 2
+int foo = 1; // 3
+
+// 4
+int bar = 1; // 5''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '// 2', endsAfter: '// 3'),
+      1: _range(startsBefore: '// 4', endsAfter: '// 5'),
+    });
+  }
+
+  Future<void>
+      test_topLevel_noTrailingNewline_leadingAndTrailing_withClassBraceTrailing() async {
+    await resolveTestCode('''
+import '';
+
+// 2
+int foo = 1; // 3
+
+// 4
+int bar = 1; // 5''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '// 2', endsAfter: '// 3'),
+      1: _range(startsBefore: '// 4', endsAfter: '// 5'),
+    });
+  }
+
+  Future<void> test_topLevel_noTrailingNewline_trailing() async {
+    await resolveTestCode('''
+import '';
+
+int foo = 1; // 1
+int bar = 2; // 2''');
+    _assertUnitRanges({
+      0: _range(startsBefore: 'int foo', endsAfter: '// 1'),
+      1: _range(startsBefore: 'int bar', endsAfter: '// 2'),
+    });
+  }
+
+  Future<void> test_topLevel_single_field_leading() async {
+    await resolveTestCode('''
+import '';
+
+// 1
+int foo = 1;
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '// 1', endsAfter: '= 1;'),
+    });
+  }
+
+  Future<void> test_topLevel_single_field_leadingAndTrailing() async {
+    await resolveTestCode('''
+import '';
+
+// 1
+int foo = 1; // 2
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '// 1', endsAfter: '// 2'),
+    });
+  }
+
+  Future<void>
+      test_topLevel_single_field_leadingAndTrailing_withClassBraceTrailing() async {
+    await resolveTestCode('''
+import '';
+
+// 2
+int foo = 1; // 3
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '// 2', endsAfter: '// 3'),
+    });
+  }
+
+  Future<void> test_topLevel_single_field_trailing() async {
+    await resolveTestCode('''
+import '';
+
+int foo = 1; // 1
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: 'int foo', endsAfter: '// 1'),
+    });
+  }
+
+  Future<void> test_topLevel_single_method_leading() async {
+    await resolveTestCode('''
+import '';
+
+// 1
+foo() {}
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '// 1', endsAfter: '{}'),
+    });
+  }
+
+  Future<void> test_topLevel_single_method_leadingAndTrailing() async {
+    await resolveTestCode('''
+import '';
+
+// 1
+foo() {} // 2
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '// 1', endsAfter: '// 2'),
+    });
+  }
+
+  Future<void>
+      test_topLevel_single_method_leadingAndTrailing_withClassBraceTrailing() async {
+    await resolveTestCode('''
+import '';
+
+// 1
+foo() {} // 2
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '// 1', endsAfter: '// 2'),
+    });
+  }
+
+  Future<void> test_topLevel_single_method_trailing() async {
+    await resolveTestCode('''
+foo() {} // 1
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: 'foo()', endsAfter: '// 1'),
+    });
+  }
+
+  Future<void> test_topLevel_withDirectives_leading() async {
+    await resolveTestCode('''
+import 'dart:async';
+
+// 1
+int foo = 1;
+
+// 2
+int bar = 2;
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '// 1', endsAfter: '= 1;'),
+      1: _range(startsBefore: '// 2', endsAfter: '= 2;'),
+    });
+  }
+
+  Future<void> test_topLevel_withDirectives_leadingAndTrailing() async {
+    await resolveTestCode('''
+import 'dart:async';
+
+// 2
+int foo = 1; // 3
+
+// 4
+int bar = 1; // 5
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '// 2', endsAfter: '// 3'),
+      1: _range(startsBefore: '// 4', endsAfter: '// 5'),
+    });
+  }
+
+  Future<void>
+      test_topLevel_withDirectives_leadingAndTrailing_withClassBraceTrailing() async {
+    await resolveTestCode('''
+import 'dart:async';
+
+// 2
+int foo = 1; // 3
+
+// 4
+int bar = 1; // 5
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: '// 2', endsAfter: '// 3'),
+      1: _range(startsBefore: '// 4', endsAfter: '// 5'),
+    });
+  }
+
+  Future<void> test_topLevel_withDirectives_trailing() async {
+    await resolveTestCode('''
+import 'dart:async';
+
+int foo = 1; // 1
+int bar = 2; // 2
+''');
+    _assertUnitRanges({
+      0: _range(startsBefore: 'int foo', endsAfter: '// 1'),
+      1: _range(startsBefore: 'int bar', endsAfter: '// 2'),
+    });
   }
 }
diff --git a/pkg/analysis_server/test/stress/completion/completion.dart b/pkg/analysis_server/test/stress/completion/completion.dart
index 41fc4ef..014efa1 100644
--- a/pkg/analysis_server/test/stress/completion/completion.dart
+++ b/pkg/analysis_server/test/stress/completion/completion.dart
@@ -18,10 +18,10 @@
 
     var runner = CompletionRunner(
         output: stdout,
-        printMissing: result['missing'],
-        printQuality: result['quality'],
-        timing: result['timing'],
-        verbose: result['verbose']);
+        printMissing: result['missing'] as bool?,
+        printQuality: result['quality'] as bool?,
+        timing: result['timing'] as bool?,
+        verbose: result['verbose'] as bool?);
     await runner.runAll(analysisRoot);
     await stdout.flush();
   }
diff --git a/pkg/analysis_server/test/stress/replay/operation.dart b/pkg/analysis_server/test/stress/replay/operation.dart
index a83d8b8..b8d58b8 100644
--- a/pkg/analysis_server/test/stress/replay/operation.dart
+++ b/pkg/analysis_server/test/stress/replay/operation.dart
@@ -11,7 +11,7 @@
   final String filePath;
 
   /// The overlay used to update the content.
-  final dynamic overlay;
+  final Object overlay;
 
   /// Initialize an operation to send an 'analysis.updateContent' request with
   /// the given [filePath] and [overlay] as parameters.
diff --git a/pkg/analysis_server/test/stress/replay/replay.dart b/pkg/analysis_server/test/stress/replay/replay.dart
index da2cae0..a674281 100644
--- a/pkg/analysis_server/test/stress/replay/replay.dart
+++ b/pkg/analysis_server/test/stress/replay/replay.dart
@@ -12,7 +12,6 @@
 import 'package:analyzer/error/listener.dart' as error;
 import 'package:analyzer/src/dart/scanner/reader.dart';
 import 'package:analyzer/src/dart/scanner/scanner.dart';
-import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/util/glob.dart';
 import 'package:analyzer_plugin/protocol/protocol_common.dart';
@@ -260,19 +259,19 @@
       return false;
     }
 
-    if (results[HELP_FLAG_NAME]) {
+    if (results[HELP_FLAG_NAME] as bool) {
       _showUsage(parser);
       return false;
     }
 
-    String overlayStyleValue = results[OVERLAY_STYLE_OPTION_NAME];
+    var overlayStyleValue = results[OVERLAY_STYLE_OPTION_NAME] as String;
     if (overlayStyleValue == CHANGE_OVERLAY_STYLE) {
       overlayStyle = OverlayStyle.change;
     } else if (overlayStyleValue == MULTIPLE_ADD_OVERLAY_STYLE) {
       overlayStyle = OverlayStyle.multipleAdd;
     }
 
-    if (results[VERBOSE_FLAG_NAME]) {
+    if (results[VERBOSE_FLAG_NAME] as bool) {
       verbose = true;
       logger = Logger(stdout);
     }
@@ -497,7 +496,7 @@
       throw ArgumentError('Unhandled change of type ${record.status}');
     } else {
       content = File(filePath).readAsStringSync();
-      lineInfo = LineInfo(StringUtilities.computeLineStarts(content));
+      lineInfo = LineInfo.fromContent(content);
     }
     currentContent = content;
   }
diff --git a/pkg/analysis_server/test/stress/utilities/server.dart b/pkg/analysis_server/test/stress/utilities/server.dart
index 888056a..b2eefa3 100644
--- a/pkg/analysis_server/test/stress/utilities/server.dart
+++ b/pkg/analysis_server/test/stress/utilities/server.dart
@@ -766,7 +766,7 @@
       return;
     }
     logger?.log(fromServer, '$trimmedLine');
-    var message = asMap(json.decoder.convert(trimmedLine));
+    var message = asMap(json.decoder.convert(trimmedLine) as Object);
     if (message.containsKey('id')) {
       // The message is a response.
       var response = Response.fromJson(message)!;
diff --git a/pkg/analysis_server/test/tool/completion_metrics/metrics_util_test.dart b/pkg/analysis_server/test/tool/completion_metrics/metrics_util_test.dart
index 265ac05..639b3eb 100644
--- a/pkg/analysis_server/test/tool/completion_metrics/metrics_util_test.dart
+++ b/pkg/analysis_server/test/tool/completion_metrics/metrics_util_test.dart
@@ -185,7 +185,7 @@
 }
 
 /// Returns matcher that can compare double values.
-Matcher doubleEquals(expected) => _DoubleEquals(expected);
+Matcher doubleEquals(double expected) => _DoubleEquals(expected);
 
 class _DoubleEquals extends Matcher {
   final double _value;
diff --git a/pkg/analysis_server/test/tool/lsp_spec/json_test.dart b/pkg/analysis_server/test/tool/lsp_spec/json_test.dart
index 824217e..04a78a6 100644
--- a/pkg/analysis_server/test/tool/lsp_spec/json_test.dart
+++ b/pkg/analysis_server/test/tool/lsp_spec/json_test.dart
@@ -334,7 +334,8 @@
   group('fromJson', () {
     test('parses JSON for types with unions (left side)', () {
       final input = '{"id":1,"method":"shutdown","jsonrpc":"test"}';
-      final message = RequestMessage.fromJson(jsonDecode(input));
+      final message =
+          RequestMessage.fromJson(jsonDecode(input) as Map<String, Object?>);
       expect(message.id, equals(Either2<num, String>.t1(1)));
       expect(message.id.valueEquals(1), isTrue);
       expect(message.jsonrpc, 'test');
@@ -343,7 +344,8 @@
 
     test('parses JSON for types with unions (right side)', () {
       final input = '{"id":"one","method":"shutdown","jsonrpc":"test"}';
-      final message = RequestMessage.fromJson(jsonDecode(input));
+      final message =
+          RequestMessage.fromJson(jsonDecode(input) as Map<String, Object?>);
       expect(message.id, equals(Either2<num, String>.t2('one')));
       expect(message.id.valueEquals('one'), isTrue);
       expect(message.jsonrpc, 'test');
@@ -352,13 +354,15 @@
 
     test('parses JSON with nulls for unions that allow null', () {
       final input = '{"id":null,"jsonrpc":"test"}';
-      final message = ResponseMessage.fromJson(jsonDecode(input));
+      final message =
+          ResponseMessage.fromJson(jsonDecode(input) as Map<String, Object?>);
       expect(message.id, isNull);
     });
 
     test('parses JSON with nulls for unions that allow null', () {
       final input = '{"method":"test","jsonrpc":"test"}';
-      final message = NotificationMessage.fromJson(jsonDecode(input));
+      final message = NotificationMessage.fromJson(
+          jsonDecode(input) as Map<String, Object?>);
       expect(message.params, isNull);
     });
 
@@ -370,7 +374,8 @@
             version: 111, uri: 'file:///foo/bar.dart'),
         position: Position(line: 1, character: 1),
       ).toJson());
-      final params = TextDocumentPositionParams.fromJson(jsonDecode(input));
+      final params = TextDocumentPositionParams.fromJson(
+          jsonDecode(input) as Map<String, Object?>);
       expect(params.textDocument,
           const TypeMatcher<VersionedTextDocumentIdentifier>());
     });
@@ -378,7 +383,8 @@
     test('parses JSON with unknown fields', () {
       final input =
           '{"id":1,"invalidField":true,"method":"foo","jsonrpc":"test"}';
-      final message = RequestMessage.fromJson(jsonDecode(input));
+      final message =
+          RequestMessage.fromJson(jsonDecode(input) as Map<String, Object?>);
       expect(message.id.valueEquals(1), isTrue);
       expect(message.method, equals(Method('foo')));
       expect(message.params, isNull);
@@ -401,7 +407,8 @@
       workspaceFolders: workspaceFolders,
     );
     final json = jsonEncode(obj);
-    final restoredObj = InitializeParams.fromJson(jsonDecode(json));
+    final restoredObj =
+        InitializeParams.fromJson(jsonDecode(json) as Map<String, Object?>);
     final restoredWorkspaceFolders = restoredObj.workspaceFolders!;
 
     expect(restoredWorkspaceFolders, hasLength(workspaceFolders.length));
@@ -420,7 +427,8 @@
         endCharacter: 4,
         kind: FoldingRangeKind.Comment);
     final json = jsonEncode(obj);
-    final restoredObj = FoldingRange.fromJson(jsonDecode(json));
+    final restoredObj =
+        FoldingRange.fromJson(jsonDecode(json) as Map<String, Object?>);
 
     expect(restoredObj.startLine, equals(obj.startLine));
     expect(restoredObj.startCharacter, equals(obj.startCharacter));
@@ -438,7 +446,8 @@
       'fileB': [TextEdit(range: range, newText: 'text B')]
     });
     final json = jsonEncode(obj);
-    final restoredObj = WorkspaceEdit.fromJson(jsonDecode(json));
+    final restoredObj =
+        WorkspaceEdit.fromJson(jsonDecode(json) as Map<String, Object?>);
 
     expect(restoredObj.documentChanges, equals(obj.documentChanges));
     expect(restoredObj.changes, equals(obj.changes));
diff --git a/pkg/analysis_server/test/verify_sorted_test.dart b/pkg/analysis_server/test/verify_sorted_test.dart
index 9033b16..bcde125 100644
--- a/pkg/analysis_server/test/verify_sorted_test.dart
+++ b/pkg/analysis_server/test/verify_sorted_test.dart
@@ -143,7 +143,7 @@
         if (errors.isNotEmpty) {
           fail('Errors found when parsing $path');
         }
-        var sorter = MemberSorter(code, unit);
+        var sorter = MemberSorter(code, unit, result.lineInfo);
         var edits = sorter.sort();
         if (edits.isNotEmpty) {
           fail('Unsorted file $path');
diff --git a/pkg/analysis_server/tool/bulk_fix/supported_diagnostics.dart b/pkg/analysis_server/tool/bulk_fix/supported_diagnostics.dart
index 2603f84..b2eab4e 100644
--- a/pkg/analysis_server/tool/bulk_fix/supported_diagnostics.dart
+++ b/pkg/analysis_server/tool/bulk_fix/supported_diagnostics.dart
@@ -16,8 +16,10 @@
   var hintEntries = FixProcessor.nonLintProducerMap.entries.where((e) =>
       e.key.type == ErrorType.HINT || e.key.type == ErrorType.STATIC_WARNING);
 
-  var diagnostics = List.from(hintEntries)
-    ..addAll(FixProcessor.lintProducerMap.entries);
+  var diagnostics = [
+    ...hintEntries,
+    ...FixProcessor.lintProducerMap.entries,
+  ];
   for (var diagnostic in diagnostics) {
     var canBeAppliedInBulk = false;
     var missingExplanations = <String>[];
diff --git a/pkg/analysis_server/tool/code_completion/completion_metrics.dart b/pkg/analysis_server/tool/code_completion/completion_metrics.dart
index a6a9b85..aba444c 100644
--- a/pkg/analysis_server/tool/code_completion/completion_metrics.dart
+++ b/pkg/analysis_server/tool/code_completion/completion_metrics.dart
@@ -94,7 +94,7 @@
   var provider = PhysicalResourceProvider.INSTANCE;
   if (result.wasParsed('reduceDir')) {
     var targetMetrics = <CompletionMetrics>[];
-    var dir = provider.getFolder(result['reduceDir']);
+    var dir = provider.getFolder(result['reduceDir'] as String);
     var computer = CompletionMetricsComputer('', options);
     for (var child in dir.getChildren()) {
       if (child is File) {
@@ -239,7 +239,7 @@
     printUsage(parser);
     return false;
   } else if (result.wasParsed('reduceDir')) {
-    return validateDir(parser, result['reduceDir']);
+    return validateDir(parser, result['reduceDir'] as String);
   } else if (result.rest.length != 1) {
     printUsage(parser, error: 'No package path specified.');
     return false;
@@ -402,13 +402,14 @@
         in (map['groupMrrComputers'] as Map<String, dynamic>).entries) {
       var group = CompletionGroup.values[int.parse(entry.key)];
       metrics.groupMrrComputers[group] = MeanReciprocalRankComputer(group.name)
-        ..fromJson(entry.value);
+        ..fromJson(entry.value as Map<String, Object?>);
     }
     for (var entry
         in (map['locationMrrComputers'] as Map<String, dynamic>).entries) {
       var location = entry.key;
       metrics.locationMrrComputers[location] =
-          MeanReciprocalRankComputer(location)..fromJson(entry.value);
+          MeanReciprocalRankComputer(location)
+            ..fromJson(entry.value as Map<String, Object?>);
     }
     metrics.charsBeforeTop
         .fromJson(map['charsBeforeTop'] as Map<String, dynamic>);
@@ -417,11 +418,11 @@
     metrics.insertionLengthTheoretical
         .fromJson(map['insertionLengthTheoretical'] as Map<String, dynamic>);
     for (var element in map['missingCompletionLocations'] as List<dynamic>) {
-      metrics.missingCompletionLocations.add(element);
+      metrics.missingCompletionLocations.add(element as String);
     }
     for (var element
         in map['missingCompletionLocationTables'] as List<dynamic>) {
-      metrics.missingCompletionLocationTables.add(element);
+      metrics.missingCompletionLocationTables.add(element as String);
     }
     for (var entry in (map['slowestResults'] as Map<String, dynamic>).entries) {
       var group = CompletionGroup.values[int.parse(entry.key)];
@@ -1669,15 +1670,17 @@
 
   factory CompletionMetricsOptions(results) {
     return CompletionMetricsOptions._(
-        overlay: results[OVERLAY],
-        printMissedCompletionDetails: results[PRINT_MISSED_COMPLETION_DETAILS],
-        printMissedCompletionSummary: results[PRINT_MISSED_COMPLETION_SUMMARY],
-        printMissingInformation: results[PRINT_MISSING_INFORMATION],
-        printMrrByLocation: results[PRINT_MRR_BY_LOCATION],
+        overlay: results[OVERLAY] as String,
+        printMissedCompletionDetails:
+            results[PRINT_MISSED_COMPLETION_DETAILS] as bool,
+        printMissedCompletionSummary:
+            results[PRINT_MISSED_COMPLETION_SUMMARY] as bool,
+        printMissingInformation: results[PRINT_MISSING_INFORMATION] as bool,
+        printMrrByLocation: results[PRINT_MRR_BY_LOCATION] as bool,
         printShadowedCompletionDetails:
-            results[PRINT_SHADOWED_COMPLETION_DETAILS],
-        printSlowestResults: results[PRINT_SLOWEST_RESULTS],
-        printWorstResults: results[PRINT_WORST_RESULTS]);
+            results[PRINT_SHADOWED_COMPLETION_DETAILS] as bool,
+        printSlowestResults: results[PRINT_SLOWEST_RESULTS] as bool,
+        printWorstResults: results[PRINT_WORST_RESULTS] as bool);
   }
 
   CompletionMetricsOptions._(
diff --git a/pkg/analysis_server/tool/code_completion/corpus.dart b/pkg/analysis_server/tool/code_completion/corpus.dart
index 2bde6fe..d7f02f2 100644
--- a/pkg/analysis_server/tool/code_completion/corpus.dart
+++ b/pkg/analysis_server/tool/code_completion/corpus.dart
@@ -18,7 +18,7 @@
     exit(1);
   }
 
-  final repos = [];
+  final repos = <String>[];
   if (args.length == 1 && !Directory(args[0]).existsSync()) {
     final contents = File(args[0]).readAsStringSync();
     repos.addAll(LineSplitter().convert(contents));
@@ -86,7 +86,7 @@
     result = await Process.run(
         'git', ['clone', '--recurse-submodules', '$repo.git', cloneDir]);
   }
-  return CloneResult(result.exitCode, cloneDir, msg: result.stderr);
+  return CloneResult(result.exitCode, cloneDir, msg: result.stderr as String);
 }
 
 Future<String> _getBody(String url) async => (await _getResponse(url)).body;
@@ -105,11 +105,11 @@
   if (_hasPubspec(dir)) {
     final packageFile = path.join(dir.path, _package_config);
     if (!File(packageFile).existsSync() || forcePubUpdate) {
-      print(
-          'Getting pub dependencies for "${path.relative(dir.path, from: _appDir)}"...');
+      final relativeDirPath = path.relative(dir.path, from: _appDir);
+      print('Getting pub dependencies for "$relativeDirPath"...');
       final pubRun = await _runPub(dir.path);
       if (pubRun.exitCode != 0) {
-        print('Error: ' + pubRun.stderr);
+        print('Error: ${pubRun.stderr}');
       }
     }
   }
diff --git a/pkg/analysis_server/tool/code_completion/implicit_type_declarations.dart b/pkg/analysis_server/tool/code_completion/implicit_type_declarations.dart
index 8494fb4..83be746 100644
--- a/pkg/analysis_server/tool/code_completion/implicit_type_declarations.dart
+++ b/pkg/analysis_server/tool/code_completion/implicit_type_declarations.dart
@@ -31,7 +31,7 @@
     var computer = ImpliedTypeComputer();
     var stopwatch = Stopwatch();
     stopwatch.start();
-    await computer.compute(rootPath, verbose: result['verbose']);
+    await computer.compute(rootPath, verbose: result['verbose'] as bool);
     stopwatch.stop();
 
     var duration = Duration(milliseconds: stopwatch.elapsedMilliseconds);
diff --git a/pkg/analysis_server/tool/code_completion/relevance_metrics.dart b/pkg/analysis_server/tool/code_completion/relevance_metrics.dart
index e5ad8cc..157e2be 100644
--- a/pkg/analysis_server/tool/code_completion/relevance_metrics.dart
+++ b/pkg/analysis_server/tool/code_completion/relevance_metrics.dart
@@ -51,7 +51,7 @@
     var computer = RelevanceMetricsComputer();
     var stopwatch = Stopwatch();
     stopwatch.start();
-    await computer.compute(rootPath, verbose: result['verbose']);
+    await computer.compute(rootPath, verbose: result['verbose'] as bool);
     stopwatch.stop();
 
     var duration = Duration(milliseconds: stopwatch.elapsedMilliseconds);
diff --git a/pkg/analysis_server/tool/code_completion/relevance_table_generator.dart b/pkg/analysis_server/tool/code_completion/relevance_table_generator.dart
index 30fd62f..7111493 100644
--- a/pkg/analysis_server/tool/code_completion/relevance_table_generator.dart
+++ b/pkg/analysis_server/tool/code_completion/relevance_table_generator.dart
@@ -59,7 +59,7 @@
 
     if (result.wasParsed('reduceDir')) {
       var data = RelevanceData();
-      var dir = provider.getFolder(result['reduceDir']);
+      var dir = provider.getFolder(result['reduceDir'] as String);
       var suffix = result.rest.isNotEmpty ? result.rest[0] : '';
       for (var child in dir.getChildren()) {
         if (child is File) {
@@ -76,7 +76,7 @@
 
     var computer = RelevanceMetricsComputer();
     var stopwatch = Stopwatch()..start();
-    await computer.compute(rootPath, verbose: result['verbose']);
+    await computer.compute(rootPath, verbose: result['verbose'] as bool);
     if (result.wasParsed('mapFile')) {
       var mapFile = provider.getFile(result['mapFile'] as String);
       mapFile.writeAsStringSync(computer.data.toJson());
@@ -139,7 +139,7 @@
     printUsage(parser);
     return false;
   } else if (result.wasParsed('reduceDir')) {
-    return validateDir(parser, result['reduceDir']);
+    return validateDir(parser, result['reduceDir'] as String);
   } else if (result.rest.length != 1) {
     printUsage(parser, error: 'No package path specified.');
     return false;
diff --git a/pkg/analysis_server/tool/instrumentation/log/log.dart b/pkg/analysis_server/tool/instrumentation/log/log.dart
index 503f991..4ede5ea 100644
--- a/pkg/analysis_server/tool/instrumentation/log/log.dart
+++ b/pkg/analysis_server/tool/instrumentation/log/log.dart
@@ -307,7 +307,7 @@
           if (entry.isServerStatus) {
             var analysisStatus = entry.param('analysis');
             if (analysisStatus is Map) {
-              if (analysisStatus['isAnalyzing']) {
+              if (analysisStatus['isAnalyzing'] as bool) {
                 if (analysisStartEntry != null) {
                   analysisStartEntry.recordProblem(
                       'Analysis started without being terminated.');
@@ -331,7 +331,7 @@
             }
             var pubStatus = entry.param('pub');
             if (pubStatus is Map) {
-              if (pubStatus['isListingPackageDirs']) {
+              if (pubStatus['isListingPackageDirs'] as bool) {
                 if (pubStartEntry != null) {
                   pubStartEntry.recordProblem(
                       'Pub started without previous being terminated.');
@@ -441,9 +441,9 @@
       object.forEach((key, value) {
         var newIndent = indent + singleIndent;
         buffer.write(newIndent);
-        _format(buffer, newIndent, key);
+        _format(buffer, newIndent, key as Object);
         buffer.write(' : ');
-        _format(buffer, newIndent, value);
+        _format(buffer, newIndent, value as Object);
         buffer.write('<br>');
       });
       buffer.write(indent);
@@ -453,7 +453,7 @@
       object.forEach((element) {
         var newIndent = indent + singleIndent;
         buffer.write(newIndent);
-        _format(buffer, newIndent, element);
+        _format(buffer, newIndent, element as Object);
         buffer.write('<br>');
       });
       buffer.write(indent);
@@ -578,7 +578,7 @@
       } else if (entryKind == InstrumentationLogAdapter.TAG_LOG_ENTRY) {
         // Fall through
       } else if (entryKind == InstrumentationLogAdapter.TAG_NOTIFICATION) {
-        Map requestData = json.decode(components[2]);
+        var requestData = json.decode(components[2]) as Map<Object?, Object?>;
         return NotificationEntry(index, timeStamp, requestData);
       } else if (entryKind == InstrumentationLogAdapter.TAG_PLUGIN_ERROR) {
         return PluginErrorEntry(index, timeStamp, entryKind,
@@ -588,25 +588,25 @@
             components.sublist(2, 5), components.sublist(5));
       } else if (entryKind ==
           InstrumentationLogAdapter.TAG_PLUGIN_NOTIFICATION) {
-        Map requestData = json.decode(components[2]);
+        var requestData = json.decode(components[2]) as Map<Object?, Object?>;
         return PluginNotificationEntry(
             index, timeStamp, requestData, components.sublist(3));
       } else if (entryKind == InstrumentationLogAdapter.TAG_PLUGIN_REQUEST) {
-        Map requestData = json.decode(components[2]);
+        var requestData = json.decode(components[2]) as Map<Object?, Object?>;
         return PluginRequestEntry(
             index, timeStamp, requestData, components.sublist(3));
       } else if (entryKind == InstrumentationLogAdapter.TAG_PLUGIN_RESPONSE) {
-        Map responseData = json.decode(components[2]);
+        var responseData = json.decode(components[2]) as Map<Object?, Object?>;
         return PluginResponseEntry(
             index, timeStamp, responseData, components.sublist(3));
       } else if (entryKind == InstrumentationLogAdapter.TAG_PLUGIN_TIMEOUT) {
         return PluginErrorEntry(index, timeStamp, entryKind,
             components.sublist(2, 3), components.sublist(3));
       } else if (entryKind == InstrumentationLogAdapter.TAG_REQUEST) {
-        Map requestData = json.decode(components[2]);
+        var requestData = json.decode(components[2]) as Map<Object?, Object?>;
         return RequestEntry(index, timeStamp, requestData);
       } else if (entryKind == InstrumentationLogAdapter.TAG_RESPONSE) {
-        Map responseData = json.decode(components[2]);
+        var responseData = json.decode(components[2]) as Map<Object?, Object?>;
         return ResponseEntry(index, timeStamp, responseData);
       } else if (entryKind == InstrumentationLogAdapter.TAG_VERSION) {
         // Fall through
@@ -675,7 +675,7 @@
       : super(index, timeStamp, notificationData);
 
   /// Return the event field of the request.
-  String get event => data['event'];
+  String get event => data['event'] as String;
 
   /// Return `true` if this is a server error notification.
   bool get isServerError => event == 'server.error';
@@ -747,7 +747,7 @@
       : super(index, timeStamp, notificationData, pluginData);
 
   /// Return the event field of the notification.
-  String get event => data['event'];
+  String get event => data['event'] as String;
 
   @override
   String get kind => 'PluginNoti';
@@ -773,13 +773,13 @@
       : super(index, timeStamp, requestData, pluginData);
 
   /// Return the id field of the request.
-  String get id => data['id'];
+  String get id => data['id'] as String;
 
   @override
   String get kind => 'PluginReq';
 
   /// Return the method field of the request.
-  String get method => data['method'];
+  String get method => data['method'] as String;
 
   /// Return the value of the parameter with the given [parameterName], or
   /// `null` if there is no such parameter.
@@ -802,7 +802,7 @@
       : super(index, timeStamp, responseData, pluginData);
 
   /// Return the id field of the response.
-  String get id => data['id'];
+  String get id => data['id'] as String;
 
   @override
   String get kind => 'PluginRes';
@@ -827,16 +827,16 @@
       : super(index, timeStamp, requestData);
 
   /// Return the clientRequestTime field of the request.
-  int get clientRequestTime => data['clientRequestTime'];
+  int get clientRequestTime => data['clientRequestTime'] as int;
 
   /// Return the id field of the request.
-  String get id => data['id'];
+  String get id => data['id'] as String;
 
   @override
   String get kind => 'Req';
 
   /// Return the method field of the request.
-  String get method => data['method'];
+  String get method => data['method'] as String;
 
   /// Return the value of the parameter with the given [parameterName], or
   /// `null` if there is no such parameter.
@@ -858,7 +858,7 @@
       : super(index, timeStamp, responseData);
 
   /// Return the id field of the response.
-  String get id => data['id'];
+  String get id => data['id'] as String;
 
   @override
   String get kind => 'Res';
diff --git a/pkg/analysis_server/tool/instrumentation/log_viewer.dart b/pkg/analysis_server/tool/instrumentation/log_viewer.dart
index f3e5379d..6273c47 100644
--- a/pkg/analysis_server/tool/instrumentation/log_viewer.dart
+++ b/pkg/analysis_server/tool/instrumentation/log_viewer.dart
@@ -70,14 +70,14 @@
   void start(List<String> args) {
     var parser = createParser();
     var options = parser.parse(args);
-    if (options[helpFlag]) {
+    if (options[helpFlag] as bool) {
       printUsage(parser);
       return;
     }
 
     var port = defaultPortNumber;
     try {
-      port = int.parse(options[portOption]);
+      port = int.parse(options[portOption] as String);
     } catch (exception) {
       printUsage(parser, error: 'Invalid port number');
       return;
diff --git a/pkg/analysis_server/tool/instrumentation/page/log_page.dart b/pkg/analysis_server/tool/instrumentation/page/log_page.dart
index 9288cf5..addd9dc 100644
--- a/pkg/analysis_server/tool/instrumentation/page/log_page.dart
+++ b/pkg/analysis_server/tool/instrumentation/page/log_page.dart
@@ -142,7 +142,7 @@
       if (entry.isServerStatus) {
         var analysisStatus = entry.param('analysis');
         if (analysisStatus is Map) {
-          if (analysisStatus['isAnalyzing']) {
+          if (analysisStatus['isAnalyzing'] as bool) {
             description = '$description <span class="gray">(analyzing)</span>';
           } else {
             var duration = _getDuration(pairedEntry, entry);
@@ -152,7 +152,7 @@
         }
         var pubStatus = entry.param('pub');
         if (pubStatus is Map) {
-          if (pubStatus['isListingPackageDirs']) {
+          if (pubStatus['isListingPackageDirs'] as bool) {
             description = '$description <span class="gray">(pub)</span>';
           } else {
             var duration = _getDuration(pairedEntry, entry);
diff --git a/pkg/analysis_server/tool/lsp_spec/codegen_dart.dart b/pkg/analysis_server/tool/lsp_spec/codegen_dart.dart
index 7b95c29..5383d50 100644
--- a/pkg/analysis_server/tool/lsp_spec/codegen_dart.dart
+++ b/pkg/analysis_server/tool/lsp_spec/codegen_dart.dart
@@ -60,7 +60,7 @@
       .forEach((namespace) => _namespaces[namespace.name] = namespace);
 }
 
-TypeBase resolveTypeAlias(TypeBase type, {resolveEnumClasses = false}) {
+TypeBase resolveTypeAlias(TypeBase type, {bool resolveEnumClasses = false}) {
   if (type is Type) {
     // The LSP spec contains type aliases for `integer` and `uinteger` that map
     // into the `number` type, with comments stating they must be integers. To
@@ -380,7 +380,7 @@
     ..writeIndentedln('final ${typeOfValues.dartTypeWithTypeArgs} _value;')
     ..writeln()
     ..writeIndentedln(
-        'static bool canParse(Object obj, LspJsonReporter reporter) {')
+        'static bool canParse(Object? obj, LspJsonReporter reporter) {')
     ..indent();
   if (allowsAnyValue) {
     buffer.writeIndentedln('return ');
@@ -866,7 +866,7 @@
   } else if (_isSpecType(type)) {
     buffer.write('$dartType.canParse($valueCode, $reporter)');
   } else if (type is ArrayType) {
-    buffer.write('($valueCode is List');
+    buffer.write('($valueCode is List<Object?>');
     if (fullDartType != 'Object?') {
       // TODO(dantup): If we're happy to assume we never have two lists in a union
       // we could skip this bit.
diff --git a/pkg/analysis_server/tool/lsp_spec/generate_all.dart b/pkg/analysis_server/tool/lsp_spec/generate_all.dart
index 24a06ed..f1783c2 100644
--- a/pkg/analysis_server/tool/lsp_spec/generate_all.dart
+++ b/pkg/analysis_server/tool/lsp_spec/generate_all.dart
@@ -16,7 +16,8 @@
 
 Future<void> main(List<String> arguments) async {
   final args = argParser.parse(arguments);
-  if (args[argHelp]) {
+  var help = args[argHelp] as bool;
+  if (help) {
     print(argParser.usage);
     return;
   }
@@ -189,15 +190,14 @@
   Field field(
     String name, {
     required String type,
-    array = false,
-    canBeNull = false,
-    canBeUndefined = false,
+    bool array = false,
+    bool canBeUndefined = false,
   }) {
     var fieldType =
         array ? ArrayType(Type.identifier(type)) : Type.identifier(type);
 
     return Field(
-        null, Token.identifier(name), fieldType, canBeNull, canBeUndefined);
+        null, Token.identifier(name), fieldType, false, canBeUndefined);
   }
 
   final customTypes = <AstNode>[
@@ -302,7 +302,8 @@
 }
 
 Future<List<AstNode>> getSpecClasses(ArgResults args) async {
-  if (args[argDownload]) {
+  var download = args[argDownload] as bool;
+  if (download) {
     await downloadSpec();
   }
   final spec = await readSpec();
diff --git a/pkg/analysis_server/tool/spec/generated/java/AnalysisServer.java b/pkg/analysis_server/tool/spec/generated/java/AnalysisServer.java
index 2108516..c5022ea 100644
--- a/pkg/analysis_server/tool/spec/generated/java/AnalysisServer.java
+++ b/pkg/analysis_server/tool/spec/generated/java/AnalysisServer.java
@@ -981,6 +981,20 @@
   public void search_getTypeHierarchy(String file, int offset, boolean superOnly, GetTypeHierarchyConsumer consumer);
 
   /**
+   * {@code server.cancelRequest}
+   *
+   * Requests cancellation of a request sent by the client by id. This is provided on a best-effort
+   * basis and there is no guarantee the server will be able to cancel any specific request. The
+   * server will still always produce a response to the request even in the case of cancellation, but
+   * clients should discard any results of any cancelled request because they may be incomplete or
+   * inaccurate. This request always completes without error regardless of whether the request is
+   * successfully cancelled.
+   *
+   * @param id The id of the request that should be cancelled.
+   */
+  public void server_cancelRequest(String id);
+
+  /**
    * {@code server.getVersion}
    *
    * Return the version number of the analysis server.
diff --git a/pkg/analysis_server/tool/spec/spec_input.html b/pkg/analysis_server/tool/spec/spec_input.html
index d89a44b..c634b46 100644
--- a/pkg/analysis_server/tool/spec/spec_input.html
+++ b/pkg/analysis_server/tool/spec/spec_input.html
@@ -7,7 +7,7 @@
 <body>
 <h1>Analysis Server API Specification</h1>
 <h1 style="color:#999999">Version
-  <version>1.32.7</version>
+  <version>1.32.8</version>
 </h1>
 <p>
   This document contains a specification of the API provided by the
@@ -134,6 +134,11 @@
   ignoring the item or treating it with some default/fallback handling.
 </p>
 <h3>Changelog</h3>
+<h4>1.32.8</h4>
+<ul>
+  <li>Added <tt>server.cancelRequest</tt> to allow clients to request cancellation
+  of outstanding requests.</li>
+</ul>
 <h4>1.32.7</h4>
 <ul>
   <li><tt>HoverInformation.elementDescription</tt> may now include linebreaks to
@@ -294,6 +299,26 @@
       </field>
     </params>
   </request>
+  <request method="cancelRequest">
+    <p>Requests cancellation of a request sent by the client by id.
+      This is provided on a best-effort basis and there is no
+      guarantee the server will be able to cancel any specific
+      request.
+
+      The server will still always produce a response to the request
+      even in the case of cancellation, but clients should discard
+      any results of any cancelled request because they may be
+      incomplete or inaccurate.
+      
+      This request always completes without error regardless of
+      whether the request is successfully cancelled.</p>
+    <params>
+      <field name="id">
+        <ref>String</ref>
+        <p>The id of the request that should be cancelled.</p>
+      </field>
+    </params>
+  </request>
   <notification event="connected">
     <p>
       Reports that the server is running. This notification is
diff --git a/pkg/analysis_server_client/lib/src/protocol/protocol_constants.dart b/pkg/analysis_server_client/lib/src/protocol/protocol_constants.dart
index 85a4474..00b690a 100644
--- a/pkg/analysis_server_client/lib/src/protocol/protocol_constants.dart
+++ b/pkg/analysis_server_client/lib/src/protocol/protocol_constants.dart
@@ -6,7 +6,7 @@
 // To regenerate the file, use the script
 // "pkg/analysis_server/tool/spec/generate_files".
 
-const String PROTOCOL_VERSION = '1.32.7';
+const String PROTOCOL_VERSION = '1.32.8';
 
 const String ANALYSIS_NOTIFICATION_ANALYZED_FILES = 'analysis.analyzedFiles';
 const String ANALYSIS_NOTIFICATION_ANALYZED_FILES_DIRECTORIES = 'directories';
@@ -356,6 +356,8 @@
 const String SERVER_NOTIFICATION_STATUS = 'server.status';
 const String SERVER_NOTIFICATION_STATUS_ANALYSIS = 'analysis';
 const String SERVER_NOTIFICATION_STATUS_PUB = 'pub';
+const String SERVER_REQUEST_CANCEL_REQUEST = 'server.cancelRequest';
+const String SERVER_REQUEST_CANCEL_REQUEST_ID = 'id';
 const String SERVER_REQUEST_GET_VERSION = 'server.getVersion';
 const String SERVER_REQUEST_SET_SUBSCRIPTIONS = 'server.setSubscriptions';
 const String SERVER_REQUEST_SET_SUBSCRIPTIONS_SUBSCRIPTIONS = 'subscriptions';
diff --git a/pkg/analysis_server_client/lib/src/protocol/protocol_generated.dart b/pkg/analysis_server_client/lib/src/protocol/protocol_generated.dart
index 7bb9c83..c375b0c 100644
--- a/pkg/analysis_server_client/lib/src/protocol/protocol_generated.dart
+++ b/pkg/analysis_server_client/lib/src/protocol/protocol_generated.dart
@@ -15633,6 +15633,91 @@
       );
 }
 
+/// server.cancelRequest params
+///
+/// {
+///   "id": String
+/// }
+///
+/// Clients may not extend, implement or mix-in this class.
+class ServerCancelRequestParams implements RequestParams {
+  /// The id of the request that should be cancelled.
+  String id;
+
+  ServerCancelRequestParams(this.id);
+
+  factory ServerCancelRequestParams.fromJson(
+      JsonDecoder jsonDecoder, String jsonPath, Object? json) {
+    json ??= {};
+    if (json is Map) {
+      String id;
+      if (json.containsKey('id')) {
+        id = jsonDecoder.decodeString(jsonPath + '.id', json['id']);
+      } else {
+        throw jsonDecoder.mismatch(jsonPath, 'id');
+      }
+      return ServerCancelRequestParams(id);
+    } else {
+      throw jsonDecoder.mismatch(jsonPath, 'server.cancelRequest params', json);
+    }
+  }
+
+  factory ServerCancelRequestParams.fromRequest(Request request) {
+    return ServerCancelRequestParams.fromJson(
+        RequestDecoder(request), 'params', request.params);
+  }
+
+  @override
+  Map<String, Object> toJson() {
+    var result = <String, Object>{};
+    result['id'] = id;
+    return result;
+  }
+
+  @override
+  Request toRequest(String id) {
+    return Request(id, 'server.cancelRequest', toJson());
+  }
+
+  @override
+  String toString() => json.encode(toJson());
+
+  @override
+  bool operator ==(other) {
+    if (other is ServerCancelRequestParams) {
+      return id == other.id;
+    }
+    return false;
+  }
+
+  @override
+  int get hashCode => id.hashCode;
+}
+
+/// server.cancelRequest result
+///
+/// Clients may not extend, implement or mix-in this class.
+class ServerCancelRequestResult implements ResponseResult {
+  @override
+  Map<String, Object> toJson() => <String, Object>{};
+
+  @override
+  Response toResponse(String id) {
+    return Response(id, result: null);
+  }
+
+  @override
+  bool operator ==(other) {
+    if (other is ServerCancelRequestResult) {
+      return true;
+    }
+    return false;
+  }
+
+  @override
+  int get hashCode => 183255719;
+}
+
 /// server.connected params
 ///
 /// {
diff --git a/pkg/analysis_server_client/test/verify_sorted_test.dart b/pkg/analysis_server_client/test/verify_sorted_test.dart
index f4f4c57..8380e74 100644
--- a/pkg/analysis_server_client/test/verify_sorted_test.dart
+++ b/pkg/analysis_server_client/test/verify_sorted_test.dart
@@ -65,7 +65,7 @@
         if (errors.isNotEmpty) {
           fail('Errors found when parsing $path');
         }
-        var sorter = MemberSorter(code, unit);
+        var sorter = MemberSorter(code, unit, result.lineInfo);
         var edits = sorter.sort();
         if (edits.isNotEmpty) {
           fail('Unsorted file $path');
diff --git a/pkg/analyzer/CHANGELOG.md b/pkg/analyzer/CHANGELOG.md
index a0dc0ba..a6f4d42 100644
--- a/pkg/analyzer/CHANGELOG.md
+++ b/pkg/analyzer/CHANGELOG.md
@@ -1,3 +1,27 @@
+## 3.1.0-dev
+* New internal API for `package:dart_style`.
+* Removed deprecated non-API `MockSdk` class.
+
+## 3.0.0
+* Removed deprecated `DartType.aliasElement/aliasArguments`.
+* Removed deprecated constructors from `FeatureSet`.
+* Removed `UnitElementResult.signature` - unused by clients.
+* Removed deprecated `AnalysisError.withNamedArguments`.
+* Removed deprecated `ErrorReporter.reportErrorMessage`.
+* Removed deprecated `ResourceProvider.getModificationTimes()`.
+* Removed deprecated `MemoryResourceProvider.newDummyLink()`.
+* Removed deprecated `MemoryResourceProvider.updateFile()`.
+* Removed deprecated `Resource.parent`.
+* Removed deprecated `ResultState` and `AnalysisResult.state`.
+* Removed deprecated `summary_file_builder` library.
+* Removed deprecated `message` and `correction` from `ErrorCode`.
+* Removed deprecated `lookUp` methods from `InterfaceType`.
+* Removed deprecated `InterfaceType.getSmartLeastUpperBound`.
+* Removed deprecated `path` and `uri` from `AnalysisResult`.
+* Removed deprecated methods from `AnalysisSession`.
+* Removed `TypeName` and corresponding methods.
+* Removed deprecated methods from `TypeProvider`.
+
 ## 2.8.0
 * Deprecations and renames for `getXyz` methods in `AnalysisDriver`.
 * Removed uppercase named constants from `double` in mock SDK.
diff --git a/pkg/analyzer/lib/dart/analysis/features.dart b/pkg/analyzer/lib/dart/analysis/features.dart
index 91c3a30..9922aec 100644
--- a/pkg/analyzer/lib/dart/analysis/features.dart
+++ b/pkg/analyzer/lib/dart/analysis/features.dart
@@ -3,7 +3,6 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:analyzer/src/dart/analysis/experiments.dart';
-import 'package:meta/meta.dart';
 import 'package:pub_semver/pub_semver.dart';
 
 /// Information about a single language feature whose presence or absence
@@ -35,6 +34,9 @@
   /// Feature information for generic metadata.
   static final generic_metadata = ExperimentalFeatures.generic_metadata;
 
+  /// Feature information for macros.
+  static final macros = ExperimentalFeatures.macros;
+
   /// Feature information for spread collections.
   static final spread_collections = ExperimentalFeatures.spread_collections;
 
@@ -74,23 +76,6 @@
 
 /// An unordered collection of [Feature] objects.
 abstract class FeatureSet {
-  /// Computes a set of features for use in a unit test.  Computes the set of
-  /// features enabled in [sdkVersion], plus any specified [additionalFeatures].
-  ///
-  /// If [sdkVersion] is not supplied (or is `null`), then the current set of
-  /// enabled features is used as the starting point.
-  @visibleForTesting
-  factory FeatureSet.forTesting(
-          {String sdkVersion, List<Feature> additionalFeatures}) =
-      // ignore: invalid_use_of_visible_for_testing_member
-      ExperimentStatus.forTesting;
-
-  /// Computes the set of features implied by the given set of experimental
-  /// enable flags.
-  @Deprecated("Use 'fromEnableFlags2' instead")
-  factory FeatureSet.fromEnableFlags(List<String> flags) =
-      ExperimentStatus.fromStrings;
-
   /// Computes the set of features implied by the given set of experimental
   /// enable flags.
   factory FeatureSet.fromEnableFlags2({
diff --git a/pkg/analyzer/lib/dart/analysis/results.dart b/pkg/analyzer/lib/dart/analysis/results.dart
index a6f1df5..97198d9 100644
--- a/pkg/analyzer/lib/dart/analysis/results.dart
+++ b/pkg/analyzer/lib/dart/analysis/results.dart
@@ -15,20 +15,8 @@
 ///
 /// Clients may not extend, implement or mix-in this class.
 abstract class AnalysisResult {
-  /// The absolute and normalized path of the file that was analyzed.
-  @Deprecated('Use FileResult.path instead')
-  String get path;
-
   /// Return the session used to compute this result.
   AnalysisSession get session;
-
-  /// The state of the results.
-  @Deprecated('Check for specific Result subtypes instead')
-  ResultState get state;
-
-  /// The absolute URI of the file that was analyzed.
-  @Deprecated('Use FileResult.uri instead')
-  Uri get uri;
 }
 
 /// An analysis result that includes the errors computed during analysis.
@@ -87,11 +75,9 @@
   LineInfo get lineInfo;
 
   /// The absolute and normalized path of the file that was analyzed.
-  @override
   String get path;
 
   /// The absolute URI of the file that was analyzed.
-  @override
   Uri get uri;
 }
 
@@ -254,31 +240,6 @@
   CompilationUnit get unit;
 }
 
-/// An indication of whether an analysis result is valid, and if not why.
-@Deprecated('Check for specific Result subtypes instead')
-enum ResultState {
-  /// An indication that analysis could not be performed because the path
-  /// represents a file of a type that cannot be analyzed.
-  INVALID_FILE_TYPE,
-
-  /// An indication that analysis could not be performed because the path does
-  /// not represent a file. It might represent something else, such as a
-  /// directory, or it might not represent anything.
-  @Deprecated("Check 'get exists' flag instead")
-  NOT_A_FILE,
-
-  /// An indication that analysis could not be performed because the path does
-  /// not represent the corresponding URI.
-  ///
-  /// This usually happens in Bazel workspaces, when a URI is resolved to
-  /// a generated file, but there is also a writable file to which this URI
-  /// would be resolved, if there were no generated file.
-  NOT_FILE_OF_URI,
-
-  /// An indication that analysis completed normally and the results are valid.
-  VALID
-}
-
 /// The result of computing all of the errors contained in a single file, both
 /// syntactic and semantic.
 ///
@@ -353,18 +314,6 @@
 abstract class UnitElementResult implements SomeUnitElementResult, FileResult {
   /// The element of the file.
   CompilationUnitElement get element;
-
-  /// The signature of the library containing the [element]. This is the same
-  /// signature returned by the method [AnalysisSession.getUnitElementSignature]
-  /// when given the path to the compilation unit represented by the [element].
-  ///
-  /// The signature is based on the APIs of the files of the library (including
-  /// the file itself), and the transitive closure of files imported and
-  /// exported by the library. If the signature of a file has not changed, then
-  /// there have been no changes that would cause any files that depend on it
-  /// to need to be re-analyzed.
-  @Deprecated('This field is not used by clients and will be removed')
-  String get signature;
 }
 
 /// The type of [InvalidResult] returned when something is wrong, but we
diff --git a/pkg/analyzer/lib/dart/analysis/session.dart b/pkg/analyzer/lib/dart/analysis/session.dart
index ade0e8e..dc14b0a 100644
--- a/pkg/analyzer/lib/dart/analysis/session.dart
+++ b/pkg/analyzer/lib/dart/analysis/session.dart
@@ -37,71 +37,32 @@
   /// a result state indicating the nature of the problem.
   Future<SomeErrorsResult> getErrors(String path);
 
-  /// Return a future that will complete with information about the errors
-  /// contained in the file with the given absolute, normalized [path].
-  ///
-  /// If the file cannot be analyzed by this session, then the result will have
-  /// a result state indicating the nature of the problem.
-  @Deprecated('Use getErrors() instead')
-  Future<SomeErrorsResult> getErrors2(String path);
-
   /// Return information about the file at the given absolute, normalized
   /// [path].
   SomeFileResult getFile(String path);
 
-  /// Return information about the file at the given absolute, normalized
-  /// [path].
-  @Deprecated('Use getFile() instead')
-  SomeFileResult getFile2(String path);
-
   /// Return a future that will complete with information about the library
   /// element representing the library with the given [uri].
   Future<SomeLibraryElementResult> getLibraryByUri(String uri);
 
-  /// Return a future that will complete with information about the library
-  /// element representing the library with the given [uri].
-  @Deprecated('Use getLibraryByUri() instead')
-  Future<SomeLibraryElementResult> getLibraryByUri2(String uri);
-
   /// Return information about the results of parsing units of the library file
   /// with the given absolute, normalized [path].
   SomeParsedLibraryResult getParsedLibrary(String path);
 
   /// Return information about the results of parsing units of the library file
-  /// with the given absolute, normalized [path].
-  @Deprecated('Use getParsedLibrary() instead')
-  SomeParsedLibraryResult getParsedLibrary2(String path);
-
-  /// Return information about the results of parsing units of the library file
   /// with the given library [element].
   SomeParsedLibraryResult getParsedLibraryByElement(LibraryElement element);
 
-  /// Return information about the results of parsing units of the library file
-  /// with the given library [element].
-  @Deprecated('Use getParsedLibraryByElement() instead')
-  SomeParsedLibraryResult getParsedLibraryByElement2(LibraryElement element);
-
   /// Return information about the results of parsing the file with the given
   /// absolute, normalized [path].
   SomeParsedUnitResult getParsedUnit(String path);
 
-  /// Return information about the results of parsing the file with the given
-  /// absolute, normalized [path].
-  @Deprecated('Use getParsedUnit() instead')
-  SomeParsedUnitResult getParsedUnit2(String path);
-
   /// Return a future that will complete with information about the results of
   /// resolving all of the files in the library with the given absolute,
   /// normalized [path].
   Future<SomeResolvedLibraryResult> getResolvedLibrary(String path);
 
   /// Return a future that will complete with information about the results of
-  /// resolving all of the files in the library with the given absolute,
-  /// normalized [path].
-  @Deprecated('Use getResolvedLibrary() instead')
-  Future<SomeResolvedLibraryResult> getResolvedLibrary2(String path);
-
-  /// Return a future that will complete with information about the results of
   /// resolving all of the files in the library with the library [element].
   ///
   /// Throw [ArgumentError] if the [element] was not produced by this session.
@@ -109,32 +70,13 @@
       LibraryElement element);
 
   /// Return a future that will complete with information about the results of
-  /// resolving all of the files in the library with the library [element].
-  ///
-  /// Throw [ArgumentError] if the [element] was not produced by this session.
-  @Deprecated('Use getResolvedLibraryByElement() instead')
-  Future<SomeResolvedLibraryResult> getResolvedLibraryByElement2(
-      LibraryElement element);
-
-  /// Return a future that will complete with information about the results of
   /// resolving the file with the given absolute, normalized [path].
   Future<SomeResolvedUnitResult> getResolvedUnit(String path);
 
   /// Return a future that will complete with information about the results of
-  /// resolving the file with the given absolute, normalized [path].
-  @Deprecated('Use getResolvedUnit() instead')
-  Future<SomeResolvedUnitResult> getResolvedUnit2(String path);
-
-  /// Return a future that will complete with information about the results of
   /// building the element model for the file with the given absolute,
   /// normalized [path].
   Future<SomeUnitElementResult> getUnitElement(String path);
-
-  /// Return a future that will complete with information about the results of
-  /// building the element model for the file with the given absolute,
-  /// normalized [path].
-  @Deprecated('Use getUnitElement() instead')
-  Future<SomeUnitElementResult> getUnitElement2(String path);
 }
 
 /// The exception thrown by an [AnalysisSession] if a result is requested that
diff --git a/pkg/analyzer/lib/dart/ast/ast.dart b/pkg/analyzer/lib/dart/ast/ast.dart
index a376881..a0b7a9c 100644
--- a/pkg/analyzer/lib/dart/ast/ast.dart
+++ b/pkg/analyzer/lib/dart/ast/ast.dart
@@ -38,7 +38,6 @@
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
-import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/source.dart' show LineInfo, Source;
 
 /// Two or more string literals that are implicitly concatenated because of
@@ -318,7 +317,9 @@
 
   /// Return either this node or the most immediate ancestor of this node for
   /// which the [predicate] returns `true`, or `null` if there is no such node.
-  E? thisOrAncestorMatching<E extends AstNode>(Predicate<AstNode> predicate);
+  E? thisOrAncestorMatching<E extends AstNode>(
+    bool Function(AstNode) predicate,
+  );
 
   /// Return either this node or the most immediate ancestor of this node that
   /// has the given type, or `null` if there is no such node.
@@ -592,9 +593,6 @@
 
   R? visitTypeLiteral(TypeLiteral node);
 
-  @Deprecated('Override visitNamedType instead')
-  R? visitTypeName(TypeName node);
-
   R? visitTypeParameter(TypeParameter node);
 
   R? visitTypeParameterList(TypeParameterList node);
@@ -816,6 +814,9 @@
   /// Return `true` if this class is declared to be an abstract class.
   bool get isAbstract;
 
+  /// Return the 'macro' keyword, or `null` if the keyword was absent.
+  Token? get macroKeyword;
+
   /// Return the native clause for this class, or `null` if the class does not
   /// have a native clause.
   NativeClause? get nativeClause;
@@ -903,14 +904,14 @@
   /// Return `true` if this class is declared to be an abstract class.
   bool get isAbstract;
 
+  /// Return the token for the 'macro' keyword, or `null` if this is not
+  /// defining a macro class.
+  Token? get macroKeyword;
+
   @override
   SimpleIdentifier get name;
 
   /// Return the name of the superclass of the class being declared.
-  @Deprecated('Use superclass2 instead')
-  TypeName get superclass;
-
-  /// Return the name of the superclass of the class being declared.
   NamedType get superclass2;
 
   /// Return the type parameters for the class, or `null` if the class does not
@@ -1337,10 +1338,6 @@
   Token? get period;
 
   /// Return the name of the type defining the constructor.
-  @Deprecated('Use type2 instead')
-  TypeName get type;
-
-  /// Return the name of the type defining the constructor.
   NamedType get type2;
 }
 
@@ -1577,7 +1574,9 @@
 /// The declaration of an enumeration.
 ///
 ///    enumType ::=
-///        metadata 'enum' [SimpleIdentifier] '{' [SimpleIdentifier] (',' [SimpleIdentifier])* (',')? '}'
+///        metadata 'enum' [SimpleIdentifier] [TypeParameterList]?
+///        [WithClause]? [ImplementsClause]? '{' [SimpleIdentifier]
+///        (',' [SimpleIdentifier])* (';' [ClassMember]+)? '}'
 ///
 /// Clients may not extend, implement or mix-in this class.
 abstract class EnumDeclaration implements NamedCompilationUnitMember {
@@ -1590,6 +1589,10 @@
   /// Return the 'enum' keyword.
   Token get enumKeyword;
 
+  /// Returns the `implements` clause for the enumeration, or `null` if the
+  /// enumeration does not implement any interfaces.
+  ImplementsClause? get implementsClause;
+
   /// Return the left curly bracket.
   Token get leftBracket;
 
@@ -1601,6 +1604,14 @@
 
   /// Return the right curly bracket.
   Token get rightBracket;
+
+  /// Returns the type parameters for the enumeration, or `null` if the
+  /// enumeration does not have any type parameters.
+  TypeParameterList? get typeParameters;
+
+  /// Return the `with` clause for the enumeration, or `null` if the
+  /// enumeration does not have a `with` clause.
+  WithClause? get withClause;
 }
 
 /// An export directive.
@@ -1720,10 +1731,6 @@
   Token get extendsKeyword;
 
   /// Return the name of the class that is being extended.
-  @Deprecated('Use superclass2 instead')
-  TypeName get superclass;
-
-  /// Return the name of the class that is being extended.
   NamedType get superclass2;
 }
 
@@ -2621,10 +2628,6 @@
   Token get implementsKeyword;
 
   /// Return the list of the interfaces that are being implemented.
-  @Deprecated('Use interfaces2 instead')
-  NodeList<TypeName> get interfaces;
-
-  /// Return the list of the interfaces that are being implemented.
   NodeList<NamedType> get interfaces2;
 }
 
@@ -3477,10 +3480,6 @@
   Token get onKeyword;
 
   /// Return the list of the classes are superclass constraints for the mixin.
-  @Deprecated('Use superclassConstraints2 instead')
-  NodeList<TypeName> get superclassConstraints;
-
-  /// Return the list of the classes are superclass constraints for the mixin.
   NodeList<NamedType> get superclassConstraints2;
 }
 
@@ -4362,21 +4361,8 @@
 abstract class TypeLiteral implements Expression, CommentReferableExpression {
   /// The type represented by this literal.
   NamedType get type;
-
-  /// The type represented by this literal.
-  @Deprecated('Use namedType instead')
-  TypeName get typeName;
 }
 
-/// The name of a type, which can optionally include type arguments.
-///
-///    typeName ::=
-///        [Identifier] typeArguments?
-///
-/// Clients may not extend, implement or mix-in this class.
-@Deprecated('Use NamedType instead')
-abstract class TypeName implements NamedType {}
-
 /// A type parameter.
 ///
 ///    typeParameter ::=
@@ -4577,10 +4563,6 @@
 /// Clients may not extend, implement or mix-in this class.
 abstract class WithClause implements AstNode {
   /// Return the names of the mixins that were specified.
-  @Deprecated('Use mixinTypes2 instead')
-  NodeList<TypeName> get mixinTypes;
-
-  /// Return the names of the mixins that were specified.
   NodeList<NamedType> get mixinTypes2;
 
   /// Return the token representing the 'with' keyword.
diff --git a/pkg/analyzer/lib/dart/ast/ast_factory.dart b/pkg/analyzer/lib/dart/ast/ast_factory.dart
index f4c31cb..9cb8248 100644
--- a/pkg/analyzer/lib/dart/ast/ast_factory.dart
+++ b/pkg/analyzer/lib/dart/ast/ast_factory.dart
@@ -118,7 +118,8 @@
   /// Returns a newly created class declaration. Either or both of the
   /// [comment] and [metadata] can be `null` if the class does not have the
   /// corresponding attribute. The [abstractKeyword] can be `null` if the class
-  /// is not abstract. The [typeParameters] can be `null` if the class does not
+  /// is not abstract. The [macroKeyword] can be `null` if the class is not a
+  /// macro class. The [typeParameters] can be `null` if the class does not
   /// have any type parameters. Any or all of the [extendsClause], [withClause],
   /// and [implementsClause] can be `null` if the class does not have the
   /// corresponding clause. The list of [members] can be `null` if the class
@@ -127,6 +128,7 @@
       Comment? comment,
       List<Annotation>? metadata,
       Token? abstractKeyword,
+      Token? macroKeyword,
       Token classKeyword,
       SimpleIdentifier name,
       TypeParameterList? typeParameters,
@@ -141,7 +143,8 @@
   /// and [metadata] can be `null` if the class type alias does not have the
   /// corresponding attribute. The [typeParameters] can be `null` if the class
   /// does not have any type parameters. The [abstractKeyword] can be `null` if
-  /// the class is not abstract. The [implementsClause] can be `null` if the
+  /// the class is not abstract. The [macroKeyword] can be `null` if the class
+  /// is not a macro class. The [implementsClause] can be `null` if the
   /// class does not implement any interfaces.
   ClassTypeAlias classTypeAlias(
       Comment? comment,
@@ -151,6 +154,7 @@
       TypeParameterList? typeParameters,
       Token equals,
       Token? abstractKeyword,
+      Token? macroKeyword,
       NamedType superclass,
       WithClause withClause,
       ImplementsClause? implementsClause,
@@ -301,6 +305,7 @@
   /// [comment] and [metadata] can be `null` if the declaration does not have
   /// the corresponding attribute. The list of [constants] must contain at least
   /// one value.
+  @Deprecated('Use enumDeclaration2() instead')
   EnumDeclaration enumDeclaration(
       Comment? comment,
       List<Annotation>? metadata,
@@ -308,9 +313,26 @@
       SimpleIdentifier name,
       Token leftBracket,
       List<EnumConstantDeclaration> constants,
-      List<ClassMember> members,
       Token rightBracket);
 
+  /// Returns a newly created enumeration declaration. Either or both of the
+  /// [comment] and [metadata] can be `null` if the declaration does not have
+  /// the corresponding attribute. The list of [constants] must contain at least
+  /// one value.
+  EnumDeclaration enumDeclaration2({
+    required Comment? comment,
+    required List<Annotation>? metadata,
+    required Token enumKeyword,
+    required SimpleIdentifier name,
+    required TypeParameterList? typeParameters,
+    required WithClause? withClause,
+    required ImplementsClause? implementsClause,
+    required Token leftBracket,
+    required List<EnumConstantDeclaration> constants,
+    required List<ClassMember> members,
+    required Token rightBracket,
+  });
+
   /// Returns a newly created export directive. Either or both of the
   /// [comment] and [metadata] can be `null` if the directive does not have the
   /// corresponding attribute. The list of [combinators] can be `null` if there
@@ -950,13 +972,6 @@
   /// Returns a newly created type literal.
   TypeLiteral typeLiteral({required NamedType typeName});
 
-  /// Returns a newly created type name. The [typeArguments] can be `null` if
-  /// there are no type arguments. The [question] can be `null` if there is no
-  /// question mark.
-  @Deprecated('Use namedType() instead')
-  TypeName typeName(Identifier name, TypeArgumentList? typeArguments,
-      {Token? question});
-
   /// Returns a newly created type parameter. Either or both of the [comment]
   /// and [metadata] can be `null` if the parameter does not have the
   /// corresponding attribute. The [extendsKeyword] and [bound] can be `null` if
diff --git a/pkg/analyzer/lib/dart/ast/visitor.dart b/pkg/analyzer/lib/dart/ast/visitor.dart
index 65551ac..a77a83e 100644
--- a/pkg/analyzer/lib/dart/ast/visitor.dart
+++ b/pkg/analyzer/lib/dart/ast/visitor.dart
@@ -453,8 +453,7 @@
   R? visitNamedExpression(NamedExpression node) => visitExpression(node);
 
   @override
-  // ignore: deprecated_member_use_from_same_package
-  R? visitNamedType(NamedType node) => visitTypeName(node as TypeName);
+  R? visitNamedType(NamedType node) => visitNode(node);
 
   R? visitNamespaceDirective(NamespaceDirective node) =>
       visitUriBasedDirective(node);
@@ -603,10 +602,6 @@
   @override
   R? visitTypeLiteral(TypeLiteral node) => visitExpression(node);
 
-  @Deprecated('Override visitNamedType instead')
-  @override
-  R? visitTypeName(TypeName node) => visitNode(node);
-
   @override
   R? visitTypeParameter(TypeParameter node) => visitNode(node);
 
@@ -1151,8 +1146,8 @@
 
   @override
   R? visitNamedType(NamedType node) {
-    // ignore: deprecated_member_use_from_same_package
-    return visitTypeName(node as TypeName);
+    node.visitChildren(this);
+    return null;
   }
 
   @override
@@ -1378,13 +1373,6 @@
     return null;
   }
 
-  @Deprecated('Override visitNamedType instead')
-  @override
-  R? visitTypeName(TypeName node) {
-    node.visitChildren(this);
-    return null;
-  }
-
   @override
   R? visitTypeParameter(TypeParameter node) {
     node.visitChildren(this);
@@ -1697,8 +1685,7 @@
   R? visitNamedExpression(NamedExpression node) => null;
 
   @override
-  // ignore: deprecated_member_use_from_same_package
-  R? visitNamedType(NamedType node) => visitTypeName(node as TypeName);
+  R? visitNamedType(NamedType node) => null;
 
   @override
   R? visitNativeClause(NativeClause node) => null;
@@ -1813,10 +1800,6 @@
   @override
   R? visitTypeLiteral(TypeLiteral node) => null;
 
-  @Deprecated('Override visitNamedType instead')
-  @override
-  R? visitTypeName(TypeName node) => null;
-
   @override
   R? visitTypeParameter(TypeParameter node) => null;
 
@@ -2112,8 +2095,7 @@
   R? visitNamedExpression(NamedExpression node) => _throw(node);
 
   @override
-  // ignore: deprecated_member_use_from_same_package
-  R? visitNamedType(NamedType node) => visitTypeName(node as TypeName);
+  R? visitNamedType(NamedType node) => _throw(node);
 
   @override
   R? visitNativeClause(NativeClause node) => _throw(node);
@@ -2230,10 +2212,6 @@
   @override
   R? visitTypeLiteral(TypeLiteral node) => _throw(node);
 
-  @Deprecated('Override visitNamedType instead')
-  @override
-  R? visitTypeName(TypeName node) => _throw(node);
-
   @override
   R? visitTypeParameter(TypeParameter node) => _throw(node);
 
@@ -3248,15 +3226,6 @@
     return result;
   }
 
-  @Deprecated('Override visitNamedType instead')
-  @override
-  T? visitTypeName(TypeName node) {
-    stopwatch.start();
-    T? result = _baseVisitor.visitTypeName(node);
-    stopwatch.stop();
-    return result;
-  }
-
   @override
   T? visitTypeParameter(TypeParameter node) {
     stopwatch.start();
@@ -3601,8 +3570,7 @@
   R? visitNamedExpression(NamedExpression node) => visitNode(node);
 
   @override
-  // ignore: deprecated_member_use_from_same_package
-  R? visitNamedType(NamedType node) => visitTypeName(node as TypeName);
+  R? visitNamedType(NamedType node) => visitNode(node);
 
   @override
   R? visitNativeClause(NativeClause node) => visitNode(node);
@@ -3725,10 +3693,6 @@
   @override
   R? visitTypeLiteral(TypeLiteral node) => visitNode(node);
 
-  @Deprecated('Override visitNamedType instead')
-  @override
-  R? visitTypeName(TypeName node) => visitNode(node);
-
   @override
   R? visitTypeParameter(TypeParameter node) => visitNode(node);
 
diff --git a/pkg/analyzer/lib/dart/element/element.dart b/pkg/analyzer/lib/dart/element/element.dart
index 11b9950..400e918 100644
--- a/pkg/analyzer/lib/dart/element/element.dart
+++ b/pkg/analyzer/lib/dart/element/element.dart
@@ -46,7 +46,6 @@
 import 'package:analyzer/src/dart/constant/evaluation.dart';
 import 'package:analyzer/src/dart/resolver/scope.dart' show Namespace;
 import 'package:analyzer/src/generated/engine.dart' show AnalysisContext;
-import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/utilities_dart.dart';
 import 'package:analyzer/src/task/api/model.dart' show AnalysisTarget;
@@ -727,7 +726,9 @@
   /// Return either this element or the most immediate ancestor of this element
   /// for which the [predicate] returns `true`, or `null` if there is no such
   /// element.
-  E? thisOrAncestorMatching<E extends Element>(Predicate<Element> predicate);
+  E? thisOrAncestorMatching<E extends Element>(
+    bool Function(Element) predicate,
+  );
 
   /// Return either this element or the most immediate ancestor of this element
   /// that has the given type, or `null` if there is no such element.
@@ -1049,6 +1050,8 @@
 
   R? visitPropertyAccessorElement(PropertyAccessorElement element);
 
+  R? visitSuperFormalParameterElement(SuperFormalParameterElement element);
+
   R? visitTopLevelVariableElement(TopLevelVariableElement element);
 
   R? visitTypeAliasElement(TypeAliasElement element);
@@ -1574,6 +1577,9 @@
   /// parameter.
   bool get isRequiredPositional;
 
+  /// Return `true` if this parameter is a super formal parameter.
+  bool get isSuperFormal;
+
   @override
   String get name;
 
@@ -1730,6 +1736,19 @@
   List<String> get shownNames;
 }
 
+/// A super formal parameter defined within a constructor element.
+///
+/// Clients may not extend, implement or mix-in this class.
+abstract class SuperFormalParameterElement implements ParameterElement {
+  /// The associated super-constructor parameter, from the super-constructor
+  /// that is referenced by the implicit or explicit super-constructor
+  /// invocation.
+  ///
+  /// Can be `null` for erroneous code - not existing super-constructor,
+  /// no corresponding parameter in the super-constructor.
+  ParameterElement? get superConstructorParameter;
+}
+
 /// A top-level variable.
 ///
 /// Clients may not extend, implement or mix-in this class.
diff --git a/pkg/analyzer/lib/dart/element/type.dart b/pkg/analyzer/lib/dart/element/type.dart
index 2ff16e0..e3f102e 100644
--- a/pkg/analyzer/lib/dart/element/type.dart
+++ b/pkg/analyzer/lib/dart/element/type.dart
@@ -22,7 +22,6 @@
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/nullability_suffix.dart';
 import 'package:analyzer/dart/element/type_visitor.dart';
-import 'package:analyzer/src/dart/element/type.dart' show InterfaceTypeImpl;
 
 /// The type associated with elements in the element model.
 ///
@@ -33,16 +32,6 @@
   /// Otherwise return `null`.
   InstantiatedTypeAliasElement? get alias;
 
-  /// If this type is an instantiation of a type alias, return the type
-  /// arguments used for the instantiation. Otherwise return `null`.
-  @Deprecated('Use alias instead')
-  List<DartType>? get aliasArguments;
-
-  /// If this type is an instantiation of a type alias, return it.
-  /// Otherwise return `null`.
-  @Deprecated('Use alias instead')
-  TypeAliasElement? get aliasElement;
-
   /// Return the name of this type as it should appear when presented to users
   /// in contexts such as error messages.
   ///
@@ -68,6 +57,10 @@
   /// the dart:async library.
   bool get isDartAsyncFutureOr;
 
+  /// Return `true` if this type represents the type 'Stream' defined in the
+  /// dart:async library.
+  bool get isDartAsyncStream;
+
   /// Return `true` if this type represents the type 'bool' defined in the
   /// dart:core library.
   bool get isDartCoreBool;
@@ -337,23 +330,6 @@
   /// </blockquote>
   ConstructorElement? lookUpConstructor(String? name, LibraryElement library);
 
-  /// Return the element representing the getter that results from looking up
-  /// the getter with the given [name] in this class with respect to the given
-  /// [library], or `null` if the look up fails. The behavior of this method is
-  /// defined by the Dart Language Specification in section 12.15.1:
-  /// <blockquote>
-  /// The result of looking up getter (respectively setter) <i>m</i> in class
-  /// <i>C</i> with respect to library <i>L</i> is:
-  /// * If <i>C</i> declares an instance getter (respectively setter) named
-  ///   <i>m</i> that is accessible to <i>L</i>, then that getter (respectively
-  ///   setter) is the result of the lookup. Otherwise, if <i>C</i> has a
-  ///   superclass <i>S</i>, then the result of the lookup is the result of
-  ///   looking up getter (respectively setter) <i>m</i> in <i>S</i> with
-  ///   respect to <i>L</i>. Otherwise, we say that the lookup has failed.
-  /// </blockquote>
-  @Deprecated('Use lookupGetter2 instead')
-  PropertyAccessorElement? lookUpGetter(String name, LibraryElement library);
-
   /// Return the getter with the given [name].
   ///
   /// If [concrete] is `true`, then the concrete implementation is returned,
@@ -372,93 +348,6 @@
     bool recoveryStatic = false,
   });
 
-  /// Return the element representing the getter that results from looking up
-  /// the getter with the given [name] in the superclass of this class with
-  /// respect to the given [library], or `null` if the look up fails. The
-  /// behavior of this method is defined by the Dart Language Specification in
-  /// section 12.15.1:
-  /// <blockquote>
-  /// The result of looking up getter (respectively setter) <i>m</i> in class
-  /// <i>C</i> with respect to library <i>L</i> is:
-  /// * If <i>C</i> declares an instance getter (respectively setter) named
-  ///   <i>m</i> that is accessible to <i>L</i>, then that getter (respectively
-  ///   setter) is the result of the lookup. Otherwise, if <i>C</i> has a
-  ///   superclass <i>S</i>, then the result of the lookup is the result of
-  ///   looking up getter (respectively setter) <i>m</i> in <i>S</i> with
-  ///   respect to <i>L</i>. Otherwise, we say that the lookup has failed.
-  /// </blockquote>
-  @Deprecated('Use lookupGetter2 instead')
-  PropertyAccessorElement? lookUpGetterInSuperclass(
-      String name, LibraryElement? library);
-
-  /// Look up the member with the given [name] in this type and all extended
-  /// and mixed in classes, and by default including [thisType]. If the search
-  /// fails, this will then search interfaces.
-  ///
-  /// Return the element representing the member that was found, or `null` if
-  /// there is no getter with the given name.
-  ///
-  /// The [library] determines if a private member name is visible, and does not
-  /// need to be supplied for public names.
-  @Deprecated('Use lookupGetter2 instead')
-  PropertyAccessorElement? lookUpInheritedGetter(String name,
-      {LibraryElement? library, bool thisType = true});
-
-  /// Look up the member with the given [name] in this type and all extended
-  /// and mixed in classes, starting from this type. If the search fails,
-  /// search interfaces.
-  ///
-  /// Return the element representing the member that was found, or `null` if
-  /// there is no getter with the given name.
-  ///
-  /// The [library] determines if a private member name is visible, and does not
-  /// need to be supplied for public names.
-  @Deprecated('Use lookupGetter2 and/or lookupMethod2 instead')
-  ExecutableElement? lookUpInheritedGetterOrMethod(String name,
-      {LibraryElement? library});
-
-  /// Look up the member with the given [name] in this type and all extended
-  /// and mixed in classes, and by default including [thisType]. If the search
-  /// fails, this will then search interfaces.
-  ///
-  /// Return the element representing the member that was found, or `null` if
-  /// there is no getter with the given name.
-  ///
-  /// The [library] determines if a private member name is visible, and does not
-  /// need to be supplied for public names.
-  @Deprecated('Use lookupMethod2 instead')
-  MethodElement? lookUpInheritedMethod(String name,
-      {LibraryElement? library, bool thisType = true});
-
-  /// Look up the member with the given [name] in this type and all extended
-  /// and mixed in classes, and by default including [thisType]. If the search
-  /// fails, this will then search interfaces.
-  ///
-  /// Return the element representing the member that was found, or `null` if
-  /// there is no getter with the given name.
-  ///
-  /// The [library] determines if a private member name is visible, and does not
-  /// need to be supplied for public names.
-  @Deprecated('Use lookupSetter2 instead')
-  PropertyAccessorElement? lookUpInheritedSetter(String name,
-      {LibraryElement? library, bool thisType = true});
-
-  /// Return the element representing the method that results from looking up
-  /// the method with the given [name] in this class with respect to the given
-  /// [library], or `null` if the look up fails. The behavior of this method is
-  /// defined by the Dart Language Specification in section 12.15.1:
-  /// <blockquote>
-  /// The result of looking up method <i>m</i> in class <i>C</i> with respect to
-  /// library <i>L</i> is:
-  /// * If <i>C</i> declares an instance method named <i>m</i> that is
-  ///   accessible to <i>L</i>, then that method is the result of the lookup.
-  ///   Otherwise, if <i>C</i> has a superclass <i>S</i>, then the result of the
-  ///   lookup is the result of looking up method <i>m</i> in <i>S</i> with
-  ///   respect to <i>L</i> Otherwise, we say that the lookup has failed.
-  /// </blockquote>
-  @Deprecated('Use lookupMethod2 instead')
-  MethodElement? lookUpMethod(String name, LibraryElement library);
-
   /// Return the method with the given [name].
   ///
   /// If [concrete] is `true`, then the concrete implementation is returned,
@@ -477,41 +366,6 @@
     bool recoveryStatic = false,
   });
 
-  /// Return the element representing the method that results from looking up
-  /// the method with the given [name] in the superclass of this class with
-  /// respect to the given [library], or `null` if the look up fails. The
-  /// behavior of this method is defined by the Dart Language Specification in
-  /// section 12.15.1:
-  /// <blockquote>
-  /// The result of looking up method <i>m</i> in class <i>C</i> with respect to
-  /// library <i>L</i> is:
-  /// * If <i>C</i> declares an instance method named <i>m</i> that is
-  ///   accessible to <i>L</i>, then that method is the result of the lookup.
-  ///   Otherwise, if <i>C</i> has a superclass <i>S</i>, then the result of the
-  /// * lookup is the result of looking up method <i>m</i> in <i>S</i> with
-  ///   respect to <i>L</i>.
-  /// * Otherwise, we say that the lookup has failed.
-  /// </blockquote>
-  @Deprecated('Use lookupMethod2 instead')
-  MethodElement? lookUpMethodInSuperclass(String name, LibraryElement library);
-
-  /// Return the element representing the setter that results from looking up
-  /// the setter with the given [name] in this class with respect to the given
-  /// [library], or `null` if the look up fails. The behavior of this method is
-  /// defined by the Dart Language Specification in section 12.16:
-  /// <blockquote>
-  /// The result of looking up getter (respectively setter) <i>m</i> in class
-  /// <i>C</i> with respect to library <i>L</i> is:
-  /// * If <i>C</i> declares an instance getter (respectively setter) named
-  ///   <i>m</i> that is accessible to <i>L</i>, then that getter (respectively
-  ///   setter) is the result of the lookup. Otherwise, if <i>C</i> has a
-  ///   superclass <i>S</i>, then the result of the lookup is the result of
-  ///   looking up getter (respectively setter) <i>m</i> in <i>S</i> with
-  ///   respect to <i>L</i>. Otherwise, we say that the lookup has failed.
-  /// </blockquote>
-  @Deprecated('Use lookupSetter2 instead')
-  PropertyAccessorElement? lookUpSetter(String name, LibraryElement library);
-
   /// Return the setter with the given [name].
   ///
   /// If [concrete] is `true`, then the concrete implementation is returned,
@@ -529,36 +383,6 @@
     bool inherited = false,
     bool recoveryStatic = false,
   });
-
-  /// Return the element representing the setter that results from looking up
-  /// the setter with the given [name] in the superclass of this class with
-  /// respect to the given [library], or `null` if the look up fails. The
-  /// behavior of this method is defined by the Dart Language Specification in
-  /// section 12.16:
-  /// <blockquote>
-  /// The result of looking up getter (respectively setter) <i>m</i> in class
-  /// <i>C</i> with respect to library <i>L</i> is:
-  /// * If <i>C</i> declares an instance getter (respectively setter) named
-  ///   <i>m</i> that is accessible to <i>L</i>, then that getter (respectively
-  ///   setter) is the result of the lookup. Otherwise, if <i>C</i> has a
-  ///   superclass <i>S</i>, then the result of the lookup is the result of
-  ///   looking up getter (respectively setter) <i>m</i> in <i>S</i> with
-  ///   respect to <i>L</i>. Otherwise, we say that the lookup has failed.
-  /// </blockquote>
-  @Deprecated('Use lookupSetter2 instead')
-  PropertyAccessorElement? lookUpSetterInSuperclass(
-      String name, LibraryElement library);
-
-  /// Returns a "smart" version of the "least upper bound" of the given types.
-  ///
-  /// If these types have the same element and differ only in terms of the type
-  /// arguments, attempts to find a compatible set of type arguments.
-  ///
-  /// Otherwise, returns the same result as [DartType.getLeastUpperBound].
-  @Deprecated('Use TypeSystem.leastUpperBound instead')
-  static InterfaceType getSmartLeastUpperBound(
-          InterfaceType first, InterfaceType second) =>
-      InterfaceTypeImpl.getSmartLeastUpperBound(first, second);
 }
 
 /// The type `Never` represents the uninhabited bottom type.
diff --git a/pkg/analyzer/lib/dart/element/type_provider.dart b/pkg/analyzer/lib/dart/element/type_provider.dart
index 752df98..e75d460 100644
--- a/pkg/analyzer/lib/dart/element/type_provider.dart
+++ b/pkg/analyzer/lib/dart/element/type_provider.dart
@@ -84,11 +84,6 @@
   /// Return the type representing the built-in type `Never`.
   DartType get neverType;
 
-  /// Return a list containing all of the types that cannot be either extended
-  /// or implemented.
-  @Deprecated('Use isNonSubtypableClass instead')
-  Set<ClassElement> get nonSubtypableClasses;
-
   /// Return the element representing the built-in class `Null`.
   ClassElement get nullElement;
 
@@ -138,20 +133,10 @@
   /// given [valueType]. The type has the nullability suffix of this provider.
   InterfaceType futureOrType(DartType valueType);
 
-  /// Return the instantiation of the built-in class `FutureOr` with the
-  /// given [valueType]. The type has the nullability suffix of this provider.
-  @Deprecated('Use futureOrType instead')
-  InterfaceType futureOrType2(DartType valueType);
-
   /// Return the instantiation of the built-in class `Future` with the
   /// given [valueType]. The type has the nullability suffix of this provider.
   InterfaceType futureType(DartType valueType);
 
-  /// Return the instantiation of the built-in class `Future` with the
-  /// given [valueType]. The type has the nullability suffix of this provider.
-  @Deprecated('Use futureType instead')
-  InterfaceType futureType2(DartType valueType);
-
   /// Return `true` if [element] cannot be extended, implemented, or mixed in.
   bool isNonSubtypableClass(ClassElement element);
 
@@ -169,46 +154,20 @@
   /// given [elementType]. The type has the nullability suffix of this provider.
   InterfaceType iterableType(DartType elementType);
 
-  /// Return the instantiation of the built-in class `Iterable` with the
-  /// given [elementType]. The type has the nullability suffix of this provider.
-  @Deprecated('Use iterableType instead')
-  InterfaceType iterableType2(DartType elementType);
-
   /// Return the instantiation of the built-in class `List` with the
   /// given [elementType]. The type has the nullability suffix of this provider.
   InterfaceType listType(DartType elementType);
 
   /// Return the instantiation of the built-in class `List` with the
-  /// given [elementType]. The type has the nullability suffix of this provider.
-  @Deprecated('Use listType instead')
-  InterfaceType listType2(DartType elementType);
-
-  /// Return the instantiation of the built-in class `List` with the
   /// given [keyType] and [valueType]. The type has the nullability suffix of
   /// this provider.
   InterfaceType mapType(DartType keyType, DartType valueType);
 
-  /// Return the instantiation of the built-in class `List` with the
-  /// given [keyType] and [valueType]. The type has the nullability suffix of
-  /// this provider.
-  @Deprecated('Use mapType instead')
-  InterfaceType mapType2(DartType keyType, DartType valueType);
-
   /// Return the instantiation of the built-in class `Set` with the
   /// given [elementType]. The type has the nullability suffix of this provider.
   InterfaceType setType(DartType elementType);
 
-  /// Return the instantiation of the built-in class `Set` with the
-  /// given [elementType]. The type has the nullability suffix of this provider.
-  @Deprecated('Use setType instead')
-  InterfaceType setType2(DartType elementType);
-
   /// Return the instantiation of the built-in class `Stream` with the
   /// given [elementType]. The type has the nullability suffix of this provider.
   InterfaceType streamType(DartType elementType);
-
-  /// Return the instantiation of the built-in class `Stream` with the
-  /// given [elementType]. The type has the nullability suffix of this provider.
-  @Deprecated('Use streamType instead')
-  InterfaceType streamType2(DartType elementType);
 }
diff --git a/pkg/analyzer/lib/dart/element/visitor.dart b/pkg/analyzer/lib/dart/element/visitor.dart
index 0654527..aede2b6 100644
--- a/pkg/analyzer/lib/dart/element/visitor.dart
+++ b/pkg/analyzer/lib/dart/element/visitor.dart
@@ -169,6 +169,10 @@
       visitVariableElement(element);
 
   @override
+  R? visitSuperFormalParameterElement(SuperFormalParameterElement element) =>
+      visitParameterElement(element);
+
+  @override
   R? visitTopLevelVariableElement(TopLevelVariableElement element) =>
       visitPropertyInducingElement(element);
 
@@ -306,6 +310,12 @@
   }
 
   @override
+  R? visitSuperFormalParameterElement(SuperFormalParameterElement element) {
+    element.visitChildren(this);
+    return null;
+  }
+
+  @override
   R? visitTopLevelVariableElement(TopLevelVariableElement element) {
     element.visitChildren(this);
     return null;
@@ -391,6 +401,10 @@
   R? visitPropertyAccessorElement(PropertyAccessorElement element) => null;
 
   @override
+  R? visitSuperFormalParameterElement(SuperFormalParameterElement element) =>
+      null;
+
+  @override
   R? visitTopLevelVariableElement(TopLevelVariableElement element) => null;
 
   @override
@@ -471,6 +485,10 @@
       _throw(element);
 
   @override
+  R? visitSuperFormalParameterElement(SuperFormalParameterElement element) =>
+      _throw(element);
+
+  @override
   R? visitTopLevelVariableElement(TopLevelVariableElement element) =>
       _throw(element);
 
diff --git a/pkg/analyzer/lib/error/error.dart b/pkg/analyzer/lib/error/error.dart
index b4924ce..25895fe 100644
--- a/pkg/analyzer/lib/error/error.dart
+++ b/pkg/analyzer/lib/error/error.dart
@@ -477,6 +477,7 @@
   CompileTimeErrorCode.YIELD_IN_NON_GENERATOR,
   CompileTimeErrorCode.YIELD_EACH_OF_INVALID_TYPE,
   CompileTimeErrorCode.YIELD_OF_INVALID_TYPE,
+  FfiCode.ABI_SPECIFIC_INTEGER_INVALID,
   FfiCode.ABI_SPECIFIC_INTEGER_MAPPING_EXTRA,
   FfiCode.ABI_SPECIFIC_INTEGER_MAPPING_MISSING,
   FfiCode.ABI_SPECIFIC_INTEGER_MAPPING_UNSUPPORTED,
@@ -522,6 +523,7 @@
   FfiCode.SUBTYPE_OF_STRUCT_CLASS_IN_WITH,
   HintCode.ARGUMENT_TYPE_NOT_ASSIGNABLE_TO_ERROR_HANDLER,
   HintCode.ASSIGNMENT_OF_DO_NOT_STORE,
+  HintCode.BODY_MIGHT_COMPLETE_NORMALLY_NULLABLE,
   HintCode.CAN_BE_NULL_AFTER_NULL_AWARE,
   HintCode.DEAD_CODE,
   HintCode.DEAD_CODE_CATCH_FOLLOWING_CATCH,
@@ -1024,21 +1026,6 @@
         url: null);
   }
 
-  /// Initialize a newly created analysis error. The error is associated with
-  /// the given [source] and is located at the given [offset] with the given
-  /// [length]. The error will have the given [errorCode] and the map  of
-  /// [arguments] will be used to complete the message and correction. If any
-  /// [contextMessages] are provided, they will be recorded with the error.
-  ///
-  /// Deprecated - no analyzer errors use named arguments anymore.  Please use
-  /// `AnalysisError()`.
-  @deprecated
-  AnalysisError.withNamedArguments(Source source, int offset, int length,
-      ErrorCode errorCode, Map<String, dynamic> arguments,
-      {List<DiagnosticMessage> contextMessages = const []})
-      : this(source, offset, length, errorCode,
-            _translateNamedArguments(arguments), contextMessages);
-
   @override
   List<DiagnosticMessage> get contextMessages => _contextMessages;
 
@@ -1137,20 +1124,4 @@
     }
     return errors.toList();
   }
-
-  static Null _translateNamedArguments(Map<String, dynamic> arguments) {
-    // All analyzer errors now use positional arguments, so if this method is
-    // being called, either no arguments were provided to the
-    // AnalysisError.withNamedArguments constructor, or the client was
-    // developed against an older version of the analyzer that used named
-    // arguments.  In either case, we'll make a best effort translation of named
-    // arguments to positional ones.  In the case where some arguments were
-    // provided, we have an assertion to alert the developer that they may not
-    // get correct results.
-    assert(
-        arguments.isEmpty,
-        'AnalysisError.withNamedArguments is no longer supported.  Making a '
-        'best effort translation to positional arguments.  Please use '
-        'AnalysisError() instead.');
-  }
 }
diff --git a/pkg/analyzer/lib/error/listener.dart b/pkg/analyzer/lib/error/listener.dart
index 6209775..807499c 100644
--- a/pkg/analyzer/lib/error/listener.dart
+++ b/pkg/analyzer/lib/error/listener.dart
@@ -4,7 +4,6 @@
 
 import 'dart:collection';
 
-import 'package:_fe_analyzer_shared/src/messages/codes.dart' show Message;
 import 'package:analyzer/dart/ast/ast.dart'
     show AstNode, ConstructorDeclaration;
 import 'package:analyzer/dart/ast/token.dart';
@@ -125,19 +124,6 @@
         errorCode, token.offset, token.length, arguments, messages);
   }
 
-  /// Report an error with the given [errorCode] and [message]. The location of
-  /// the error is specified by the given [offset] and [length].
-  ///
-  /// Deprecated - the [Message] type assumes named arguments, and no analyzer
-  /// errors use named arguments anymore.  Please use other methods of
-  /// [ErrorReporter].
-  @deprecated
-  void reportErrorMessage(
-      ErrorCode errorCode, int offset, int length, Message message) {
-    _errorListener.onError(AnalysisError.withNamedArguments(
-        _source, offset, length, errorCode, message.arguments));
-  }
-
   /// Report an error with the given [errorCode] and [arguments]. The [node] is
   /// used to compute the location of the error. The arguments are expected to
   /// contain two or more types. Convert the types into strings by using the
diff --git a/pkg/analyzer/lib/file_system/file_system.dart b/pkg/analyzer/lib/file_system/file_system.dart
index 52bb3d7..0a2bd5d 100644
--- a/pkg/analyzer/lib/file_system/file_system.dart
+++ b/pkg/analyzer/lib/file_system/file_system.dart
@@ -127,11 +127,6 @@
   /// Return `true` if this resource exists.
   bool get exists;
 
-  /// Return the [Folder] that contains this resource, or `null` if this
-  /// resource is a root folder.
-  @Deprecated('Use parent2 instead')
-  Folder? get parent;
-
   /// Return the [Folder] that contains this resource, possibly itself if this
   /// resource is a root folder.
   Folder get parent2;
@@ -196,13 +191,6 @@
   /// A folder may or may not exist at this location.
   Folder getFolder(String path);
 
-  /// Complete with a list of modification times for the given [sources].
-  ///
-  /// If the file of a source is not managed by this provider, return `null`.
-  /// If the file a source does not exist, return `-1`.
-  @Deprecated('Not used by clients')
-  Future<List<int?>> getModificationTimes(List<Source> sources);
-
   /// Return the [Resource] that corresponds to the given [path].
   ///
   /// The [path] must be absolute and normalized.
diff --git a/pkg/analyzer/lib/file_system/memory_file_system.dart b/pkg/analyzer/lib/file_system/memory_file_system.dart
index ce09cee..21ffb07 100644
--- a/pkg/analyzer/lib/file_system/memory_file_system.dart
+++ b/pkg/analyzer/lib/file_system/memory_file_system.dart
@@ -22,8 +22,7 @@
 
   final pathos.Context _pathContext;
 
-  MemoryResourceProvider(
-      {pathos.Context? context, @deprecated bool isWindows = false})
+  MemoryResourceProvider({pathos.Context? context})
       : _pathContext = context ??= pathos.style == pathos.Style.windows
             // On Windows, ensure that the current drive matches
             // the drive inserted by MemoryResourceProvider.convertPath
@@ -106,20 +105,6 @@
     return _MemoryFolder(this, path);
   }
 
-  @Deprecated('Not used by clients')
-  @override
-  Future<List<int>> getModificationTimes(List<Source> sources) async {
-    return sources.map((source) {
-      String path = source.fullName;
-      var file = getFile(path);
-      try {
-        return file.modificationStamp;
-      } on FileSystemException {
-        return -1;
-      }
-    }).toList();
-  }
-
   @override
   Resource getResource(String path) {
     _ensureAbsoluteAndNormalized(path);
@@ -148,17 +133,6 @@
     _notifyWatchers(path, ChangeType.MODIFY);
   }
 
-  /// Create a resource representing a dummy link (that is, a File object which
-  /// appears in its parent directory, but whose `exists` property is false)
-  @Deprecated('Not used by clients')
-  File newDummyLink(String path) {
-    _ensureAbsoluteAndNormalized(path);
-    newFolder(pathContext.dirname(path));
-    _MemoryDummyLink link = _MemoryDummyLink(this, path);
-    _notifyWatchers(path, ChangeType.ADD);
-    return link;
-  }
-
   File newFile(
     String path,
     String content, [
@@ -202,18 +176,6 @@
     _pathToLinkedPath[path] = target;
   }
 
-  @Deprecated('Not used by clients')
-  File updateFile(String path, String content, [int? stamp]) {
-    _ensureAbsoluteAndNormalized(path);
-    newFolder(pathContext.dirname(path));
-    _pathToData[path] = _FileData(
-      bytes: utf8.encode(content) as Uint8List,
-      timeStamp: stamp ?? nextStamp++,
-    );
-    _notifyWatchers(path, ChangeType.MODIFY);
-    return _MemoryFile(this, path);
-  }
-
   /// Write a representation of the file system on the given [sink].
   void writeOn(StringSink sink) {
     List<String> paths = _pathToData.keys.toList();
@@ -360,81 +322,6 @@
   final List<String> childNames = [];
 }
 
-/// An in-memory implementation of [File] which acts like a symbolic link to a
-/// non-existent file.
-class _MemoryDummyLink extends _MemoryResource implements File {
-  _MemoryDummyLink(MemoryResourceProvider provider, String path)
-      : super(provider, path);
-
-  @override
-  Stream<WatchEvent> get changes {
-    throw FileSystemException(path, "File does not exist");
-  }
-
-  @override
-  bool get exists => false;
-
-  @override
-  int get lengthSync {
-    throw FileSystemException(path, 'File could not be read');
-  }
-
-  @override
-  int get modificationStamp {
-    throw FileSystemException(path, "File does not exist");
-  }
-
-  @override
-  File copyTo(Folder parentFolder) {
-    throw FileSystemException(path, 'File could not be copied');
-  }
-
-  @override
-  Source createSource([Uri? uri]) {
-    throw FileSystemException(path, 'File could not be read');
-  }
-
-  @override
-  void delete() {
-    throw FileSystemException(path, 'File could not be deleted');
-  }
-
-  @override
-  bool isOrContains(String path) {
-    return path == this.path;
-  }
-
-  @override
-  Uint8List readAsBytesSync() {
-    throw FileSystemException(path, 'File could not be read');
-  }
-
-  @override
-  String readAsStringSync() {
-    throw FileSystemException(path, 'File could not be read');
-  }
-
-  @override
-  File renameSync(String newPath) {
-    throw FileSystemException(path, 'File could not be renamed');
-  }
-
-  @override
-  File resolveSymbolicLinksSync() {
-    return throw FileSystemException(path, "File does not exist");
-  }
-
-  @override
-  void writeAsBytesSync(List<int> bytes) {
-    throw FileSystemException(path, 'File could not be written');
-  }
-
-  @override
-  void writeAsStringSync(String content) {
-    throw FileSystemException(path, 'File could not be written');
-  }
-}
-
 /// An in-memory implementation of [File].
 class _MemoryFile extends _MemoryResource implements File {
   _MemoryFile(MemoryResourceProvider provider, String path)
@@ -699,16 +586,6 @@
   @override
   int get hashCode => path.hashCode;
 
-  @Deprecated('Use parent2 instead')
-  @override
-  Folder? get parent {
-    String parentPath = provider.pathContext.dirname(path);
-    if (parentPath == path) {
-      return null;
-    }
-    return provider.getFolder(parentPath);
-  }
-
   @override
   Folder get parent2 {
     String parentPath = provider.pathContext.dirname(path);
diff --git a/pkg/analyzer/lib/file_system/overlay_file_system.dart b/pkg/analyzer/lib/file_system/overlay_file_system.dart
index 559d80e..00d6da8 100644
--- a/pkg/analyzer/lib/file_system/overlay_file_system.dart
+++ b/pkg/analyzer/lib/file_system/overlay_file_system.dart
@@ -40,16 +40,6 @@
   Folder getFolder(String path) =>
       _OverlayFolder(this, baseProvider.getFolder(path));
 
-  @Deprecated('Not used by clients')
-  @override
-  Future<List<int>> getModificationTimes(List<Source> sources) async {
-    return sources.map((source) {
-      String path = source.fullName;
-      return _overlays[path]?.modificationStamp ??
-          baseProvider.getFile(path).modificationStamp;
-    }).toList();
-  }
-
   @override
   Resource getResource(String path) {
     if (hasOverlay(path)) {
@@ -354,16 +344,6 @@
   @override
   int get hashCode => path.hashCode;
 
-  @Deprecated('Use parent2 instead')
-  @override
-  Folder? get parent {
-    Folder? parent = _resource.parent;
-    if (parent == null) {
-      return null;
-    }
-    return _OverlayFolder(provider, parent);
-  }
-
   @override
   Folder get parent2 {
     var parent = _resource.parent2;
diff --git a/pkg/analyzer/lib/file_system/physical_file_system.dart b/pkg/analyzer/lib/file_system/physical_file_system.dart
index 3f16df1..bc4791d 100644
--- a/pkg/analyzer/lib/file_system/physical_file_system.dart
+++ b/pkg/analyzer/lib/file_system/physical_file_system.dart
@@ -32,27 +32,6 @@
       : null;
 }
 
-/// Return modification times for every file path in [paths].
-///
-/// If a path is `null`, the modification time is also `null`.
-///
-/// If any exception happens, the file is considered as a not existing and
-/// `-1` is its modification time.
-List<int?> _pathsToTimes(List<String?> paths) {
-  return paths.map((path) {
-    if (path != null) {
-      try {
-        io.File file = io.File(path);
-        return file.lastModifiedSync().millisecondsSinceEpoch;
-      } catch (_) {
-        return -1;
-      }
-    } else {
-      return null;
-    }
-  }).toList();
-}
-
 /// A `dart:io` based implementation of [ResourceProvider].
 class PhysicalResourceProvider implements ResourceProvider {
   static final PhysicalResourceProvider INSTANCE = PhysicalResourceProvider();
@@ -78,13 +57,6 @@
     return _PhysicalFolder(io.Directory(path));
   }
 
-  @Deprecated('Not used by clients')
-  @override
-  Future<List<int?>> getModificationTimes(List<Source> sources) async {
-    List<String> paths = sources.map((source) => source.fullName).toList();
-    return _pathsToTimes(paths);
-  }
-
   @override
   Resource getResource(String path) {
     _ensureAbsoluteAndNormalized(path);
@@ -356,16 +328,6 @@
   @override
   int get hashCode => path.hashCode;
 
-  @Deprecated('Use parent2 instead')
-  @override
-  Folder? get parent {
-    String parentPath = pathContext.dirname(path);
-    if (parentPath == path) {
-      return null;
-    }
-    return _PhysicalFolder(io.Directory(parentPath));
-  }
-
   @override
   Folder get parent2 {
     String parentPath = pathContext.dirname(path);
diff --git a/pkg/analyzer/lib/source/line_info.dart b/pkg/analyzer/lib/source/line_info.dart
index b552a35..41ce1ac 100644
--- a/pkg/analyzer/lib/source/line_info.dart
+++ b/pkg/analyzer/lib/source/line_info.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'package:analyzer/src/generated/java_engine.dart';
-
 /// The location of a character represented as a line and column pair.
 class CharacterLocation {
   /// The one-based index of the line containing the character.
@@ -45,9 +43,32 @@
   }
 
   /// Initialize a newly created set of line information corresponding to the
-  /// given file [content].
-  factory LineInfo.fromContent(String content) =>
-      LineInfo(StringUtilities.computeLineStarts(content));
+  /// given file [content]. Lines end with `\r`, `\n` or `\r\n`.
+  factory LineInfo.fromContent(String content) {
+    const slashN = 0x0A;
+    const slashR = 0x0D;
+
+    var lineStarts = <int>[0];
+    var length = content.length;
+    for (var i = 0; i < length; i++) {
+      var unit = content.codeUnitAt(i);
+      // Special-case \r\n.
+      if (unit == slashR) {
+        // Peek ahead to detect a following \n.
+        if (i + 1 < length && content.codeUnitAt(i + 1) == slashN) {
+          // Line start will get registered at next index at the \n.
+        } else {
+          lineStarts.add(i + 1);
+        }
+      }
+      // \n
+      if (unit == slashN) {
+        lineStarts.add(i + 1);
+      }
+    }
+
+    return LineInfo(lineStarts);
+  }
 
   /// The number of lines.
   int get lineCount => lineStarts.length;
diff --git a/pkg/analyzer/lib/src/analysis_options/error/option_codes.g.dart b/pkg/analyzer/lib/src/analysis_options/error/option_codes.g.dart
index be84490..7690c44 100644
--- a/pkg/analyzer/lib/src/analysis_options/error/option_codes.g.dart
+++ b/pkg/analyzer/lib/src/analysis_options/error/option_codes.g.dart
@@ -193,7 +193,8 @@
     'SPEC_MODE_REMOVED',
     "The option 'strong-mode: false' is no longer supported.",
     correctionMessage:
-        "It's recommended to remove the 'strong-mode:' setting (and make your code Dart 2 compliant).",
+        "It's recommended to remove the 'strong-mode:' setting (and make your "
+        "code Dart 2 compliant).",
   );
 
   /**
@@ -235,7 +236,8 @@
   static const AnalysisOptionsWarningCode UNSUPPORTED_OPTION_WITH_LEGAL_VALUE =
       AnalysisOptionsWarningCode(
     'UNSUPPORTED_OPTION_WITH_LEGAL_VALUE',
-    "The option '{1}' isn't supported by '{0}'. Try using the only supported option: '{2}'.",
+    "The option '{1}' isn't supported by '{0}'. Try using the only supported "
+        "option: '{2}'.",
   );
 
   /**
diff --git a/pkg/analyzer/lib/src/clients/dart_style/rewrite_cascade.dart b/pkg/analyzer/lib/src/clients/dart_style/rewrite_cascade.dart
new file mode 100644
index 0000000..dc054a8
--- /dev/null
+++ b/pkg/analyzer/lib/src/clients/dart_style/rewrite_cascade.dart
@@ -0,0 +1,114 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/ast/standard_ast_factory.dart';
+import 'package:analyzer/dart/ast/token.dart';
+
+/// Parenthesize the target of the [expressionStatement]'s expression (assumed
+/// to [cascadeExpression]) before removing the cascade.
+ExpressionStatement fixCascadeByParenthesizingTarget({
+  required ExpressionStatement expressionStatement,
+  required CascadeExpression cascadeExpression,
+}) {
+  assert(cascadeExpression.cascadeSections.length == 1);
+
+  var newTarget = astFactory.parenthesizedExpression(
+    Token(TokenType.OPEN_PAREN, 0)
+      ..previous = expressionStatement.beginToken.previous
+      ..next = cascadeExpression.target.beginToken,
+    cascadeExpression.target,
+    Token(TokenType.CLOSE_PAREN, 0)
+      ..previous = cascadeExpression.target.endToken
+      ..next = expressionStatement.semicolon,
+  );
+
+  return astFactory.expressionStatement(
+    astFactory.cascadeExpression(
+      newTarget,
+      cascadeExpression.cascadeSections,
+    ),
+    expressionStatement.semicolon,
+  );
+}
+
+/// Recursively insert [cascadeTarget] (the LHS of the cascade) into the
+/// LHS of the assignment expression that used to be the cascade's RHS.
+Expression insertCascadeTargetIntoExpression({
+  required Expression expression,
+  required Expression cascadeTarget,
+}) {
+  // Base case: We've recursed as deep as possible.
+  if (expression == cascadeTarget) return cascadeTarget;
+
+  // Otherwise, copy `expression` and recurse into its LHS.
+  if (expression is AssignmentExpression) {
+    return astFactory.assignmentExpression(
+      insertCascadeTargetIntoExpression(
+        expression: expression.leftHandSide,
+        cascadeTarget: cascadeTarget,
+      ),
+      expression.operator,
+      expression.rightHandSide,
+    );
+  } else if (expression is IndexExpression) {
+    var expressionTarget = expression.realTarget;
+    var question = expression.question;
+
+    // A null-aware cascade treats the `?` in `?..` as part of the token, but
+    // for a non-cascade index, it is a separate `?` token.
+    if (expression.period?.type == TokenType.QUESTION_PERIOD_PERIOD) {
+      question = _synthesizeToken(TokenType.QUESTION, expression.period!);
+    }
+
+    return astFactory.indexExpressionForTarget2(
+      target: insertCascadeTargetIntoExpression(
+        expression: expressionTarget,
+        cascadeTarget: cascadeTarget,
+      ),
+      question: question,
+      leftBracket: expression.leftBracket,
+      index: expression.index,
+      rightBracket: expression.rightBracket,
+    );
+  } else if (expression is MethodInvocation) {
+    var expressionTarget = expression.realTarget!;
+    return astFactory.methodInvocation(
+      insertCascadeTargetIntoExpression(
+        expression: expressionTarget,
+        cascadeTarget: cascadeTarget,
+      ),
+      // If we've reached the end, replace the `..` operator with `.`
+      expressionTarget == cascadeTarget
+          ? _synthesizeToken(TokenType.PERIOD, expression.operator!)
+          : expression.operator,
+      expression.methodName,
+      expression.typeArguments,
+      expression.argumentList,
+    );
+  } else if (expression is PropertyAccess) {
+    var expressionTarget = expression.realTarget;
+    return astFactory.propertyAccess(
+      insertCascadeTargetIntoExpression(
+        expression: expressionTarget,
+        cascadeTarget: cascadeTarget,
+      ),
+      // If we've reached the end, replace the `..` operator with `.`
+      expressionTarget == cascadeTarget
+          ? _synthesizeToken(TokenType.PERIOD, expression.operator)
+          : expression.operator,
+      expression.propertyName,
+    );
+  }
+  throw UnimplementedError('Unhandled ${expression.runtimeType}'
+      '($expression)');
+}
+
+/// Synthesize a token with [type] to replace the given [operator].
+///
+/// Offset, comments, and previous/next links are all preserved.
+Token _synthesizeToken(TokenType type, Token operator) =>
+    Token(type, operator.offset, operator.precedingComments)
+      ..previous = operator.previous
+      ..next = operator.next;
diff --git a/pkg/analyzer/lib/src/dart/analysis/driver.dart b/pkg/analyzer/lib/src/dart/analysis/driver.dart
index f632148..8b728b5 100644
--- a/pkg/analyzer/lib/src/dart/analysis/driver.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/driver.dart
@@ -83,7 +83,7 @@
 /// TODO(scheglov) Clean up the list of implicitly analyzed files.
 class AnalysisDriver implements AnalysisDriverGeneric {
   /// The version of data format, should be incremented on every format change.
-  static const int DATA_VERSION = 191;
+  static const int DATA_VERSION = 193;
 
   /// The number of exception contexts allowed to write. Once this field is
   /// zero, we stop writing any new exception contexts in this process.
@@ -779,7 +779,7 @@
       units.add(unitResult);
     }
 
-    return ParsedLibraryResultImpl(currentSession, path, file.uri, units);
+    return ParsedLibraryResultImpl(currentSession, units);
   }
 
   /// Return a [ParsedLibraryResult] for the library with the given [uri].
@@ -1547,8 +1547,6 @@
 
       return ResolvedLibraryResultImpl(
         currentSession,
-        library.path,
-        library.uri,
         resolvedUnits.first.libraryElement,
         resolvedUnits,
       );
@@ -1579,7 +1577,6 @@
         file.uri,
         file.lineInfo,
         file.isPart,
-        library.transitiveSignature,
         element,
       );
     });
diff --git a/pkg/analyzer/lib/src/dart/analysis/experiments.dart b/pkg/analyzer/lib/src/dart/analysis/experiments.dart
index 7d99407..b00f8df 100644
--- a/pkg/analyzer/lib/src/dart/analysis/experiments.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/experiments.dart
@@ -51,37 +51,6 @@
     return ExperimentStatus.latestLanguageVersion();
   }
 
-  /// Computes a set of features for use in a unit test.  Computes the set of
-  /// features enabled in [sdkVersion], plus any specified [additionalFeatures].
-  ///
-  /// If [sdkVersion] is not supplied (or is `null`), then the current set of
-  /// enabled features is used as the starting point.
-  @visibleForTesting
-  factory ExperimentStatus.forTesting(
-      // ignore:avoid_unused_constructor_parameters
-      {String? sdkVersion,
-      List<Feature> additionalFeatures = const []}) {
-    var explicitFlags = decodeExplicitFlags([]);
-    for (var feature in additionalFeatures) {
-      explicitFlags.enabled[(feature as ExperimentalFeature).index] = true;
-    }
-
-    var sdkLanguageVersion = currentVersion;
-    var flags = restrictEnableFlagsToVersion(
-      sdkLanguageVersion: sdkLanguageVersion,
-      explicitEnabledFlags: explicitFlags.enabled,
-      explicitDisabledFlags: explicitFlags.disabled,
-      version: sdkLanguageVersion,
-    );
-
-    return ExperimentStatus._(
-      sdkLanguageVersion,
-      explicitFlags.enabled,
-      explicitFlags.disabled,
-      flags,
-    );
-  }
-
   factory ExperimentStatus.fromStorage(Uint8List encoded) {
     var byteIndex = 0;
 
@@ -121,19 +90,6 @@
   /// Always succeeds, even if the input flags are invalid.  Expired and
   /// unrecognized flags are ignored, conflicting flags are resolved in favor of
   /// the flag appearing last.
-  factory ExperimentStatus.fromStrings(List<String> flags) {
-    return ExperimentStatus.fromStrings2(
-      sdkLanguageVersion: currentVersion,
-      flags: flags,
-    );
-  }
-
-  /// Decodes the strings given in [flags] into a representation of the set of
-  /// experiments that should be enabled.
-  ///
-  /// Always succeeds, even if the input flags are invalid.  Expired and
-  /// unrecognized flags are ignored, conflicting flags are resolved in favor of
-  /// the flag appearing last.
   factory ExperimentStatus.fromStrings2({
     required Version sdkLanguageVersion,
     required List<String> flags,
diff --git a/pkg/analyzer/lib/src/dart/analysis/experiments.g.dart b/pkg/analyzer/lib/src/dart/analysis/experiments.g.dart
index 9d06f65..1fda845 100644
--- a/pkg/analyzer/lib/src/dart/analysis/experiments.g.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/experiments.g.dart
@@ -21,6 +21,7 @@
   EnableString.extension_methods: ExperimentalFeatures.extension_methods,
   EnableString.extension_types: ExperimentalFeatures.extension_types,
   EnableString.generic_metadata: ExperimentalFeatures.generic_metadata,
+  EnableString.macros: ExperimentalFeatures.macros,
   EnableString.named_arguments_anywhere:
       ExperimentalFeatures.named_arguments_anywhere,
   EnableString.non_nullable: ExperimentalFeatures.non_nullable,
@@ -62,6 +63,9 @@
   /// String to enable the experiment "generic-metadata"
   static const String generic_metadata = 'generic-metadata';
 
+  /// String to enable the experiment "macros"
+  static const String macros = 'macros';
+
   /// String to enable the experiment "named-arguments-anywhere"
   static const String named_arguments_anywhere = 'named-arguments-anywhere';
 
@@ -177,8 +181,18 @@
     releaseVersion: Version.parse('2.14.0'),
   );
 
-  static final named_arguments_anywhere = ExperimentalFeature(
+  static final macros = ExperimentalFeature(
     index: 8,
+    enableString: EnableString.macros,
+    isEnabledByDefault: IsEnabledByDefault.macros,
+    isExpired: IsExpired.macros,
+    documentation: 'Static meta-programming',
+    experimentalReleaseVersion: null,
+    releaseVersion: null,
+  );
+
+  static final named_arguments_anywhere = ExperimentalFeature(
+    index: 9,
     enableString: EnableString.named_arguments_anywhere,
     isEnabledByDefault: IsEnabledByDefault.named_arguments_anywhere,
     isExpired: IsExpired.named_arguments_anywhere,
@@ -188,7 +202,7 @@
   );
 
   static final non_nullable = ExperimentalFeature(
-    index: 9,
+    index: 10,
     enableString: EnableString.non_nullable,
     isEnabledByDefault: IsEnabledByDefault.non_nullable,
     isExpired: IsExpired.non_nullable,
@@ -198,7 +212,7 @@
   );
 
   static final nonfunction_type_aliases = ExperimentalFeature(
-    index: 10,
+    index: 11,
     enableString: EnableString.nonfunction_type_aliases,
     isEnabledByDefault: IsEnabledByDefault.nonfunction_type_aliases,
     isExpired: IsExpired.nonfunction_type_aliases,
@@ -208,7 +222,7 @@
   );
 
   static final set_literals = ExperimentalFeature(
-    index: 11,
+    index: 12,
     enableString: EnableString.set_literals,
     isEnabledByDefault: IsEnabledByDefault.set_literals,
     isExpired: IsExpired.set_literals,
@@ -218,7 +232,7 @@
   );
 
   static final spread_collections = ExperimentalFeature(
-    index: 12,
+    index: 13,
     enableString: EnableString.spread_collections,
     isEnabledByDefault: IsEnabledByDefault.spread_collections,
     isExpired: IsExpired.spread_collections,
@@ -228,7 +242,7 @@
   );
 
   static final super_parameters = ExperimentalFeature(
-    index: 13,
+    index: 14,
     enableString: EnableString.super_parameters,
     isEnabledByDefault: IsEnabledByDefault.super_parameters,
     isExpired: IsExpired.super_parameters,
@@ -238,7 +252,7 @@
   );
 
   static final test_experiment = ExperimentalFeature(
-    index: 14,
+    index: 15,
     enableString: EnableString.test_experiment,
     isEnabledByDefault: IsEnabledByDefault.test_experiment,
     isExpired: IsExpired.test_experiment,
@@ -249,7 +263,7 @@
   );
 
   static final triple_shift = ExperimentalFeature(
-    index: 15,
+    index: 16,
     enableString: EnableString.triple_shift,
     isEnabledByDefault: IsEnabledByDefault.triple_shift,
     isExpired: IsExpired.triple_shift,
@@ -259,7 +273,7 @@
   );
 
   static final value_class = ExperimentalFeature(
-    index: 16,
+    index: 17,
     enableString: EnableString.value_class,
     isEnabledByDefault: IsEnabledByDefault.value_class,
     isExpired: IsExpired.value_class,
@@ -269,7 +283,7 @@
   );
 
   static final variance = ExperimentalFeature(
-    index: 17,
+    index: 18,
     enableString: EnableString.variance,
     isEnabledByDefault: IsEnabledByDefault.variance,
     isExpired: IsExpired.variance,
@@ -306,6 +320,9 @@
   /// Default state of the experiment "generic-metadata"
   static const bool generic_metadata = true;
 
+  /// Default state of the experiment "macros"
+  static const bool macros = false;
+
   /// Default state of the experiment "named-arguments-anywhere"
   static const bool named_arguments_anywhere = false;
 
@@ -365,6 +382,9 @@
   /// Expiration status of the experiment "generic-metadata"
   static const bool generic_metadata = false;
 
+  /// Expiration status of the experiment "macros"
+  static const bool macros = false;
+
   /// Expiration status of the experiment "named-arguments-anywhere"
   static const bool named_arguments_anywhere = false;
 
@@ -425,6 +445,9 @@
   /// Current state for the flag "generic-metadata"
   bool get generic_metadata => isEnabled(ExperimentalFeatures.generic_metadata);
 
+  /// Current state for the flag "macros"
+  bool get macros => isEnabled(ExperimentalFeatures.macros);
+
   /// Current state for the flag "named-arguments-anywhere"
   bool get named_arguments_anywhere =>
       isEnabled(ExperimentalFeatures.named_arguments_anywhere);
diff --git a/pkg/analyzer/lib/src/dart/analysis/file_state.dart b/pkg/analyzer/lib/src/dart/analysis/file_state.dart
index 532447a..2c3364c 100644
--- a/pkg/analyzer/lib/src/dart/analysis/file_state.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/file_state.dart
@@ -873,7 +873,7 @@
 
       File resource = _resourceProvider.getFile(path);
 
-      var rewrittenUri = rewriteFileToPackageUri(_sourceFactory, uri);
+      var rewrittenUri = rewriteToCanonicalUri(_sourceFactory, uri);
       if (rewrittenUri == null) {
         return Either2.t1(null);
       }
diff --git a/pkg/analyzer/lib/src/dart/analysis/file_state_filter.dart b/pkg/analyzer/lib/src/dart/analysis/file_state_filter.dart
new file mode 100644
index 0000000..828d7ad
--- /dev/null
+++ b/pkg/analyzer/lib/src/dart/analysis/file_state_filter.dart
@@ -0,0 +1,111 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analyzer/src/dart/analysis/file_state.dart';
+import 'package:analyzer/src/lint/pub.dart';
+import 'package:analyzer/src/workspace/pub.dart';
+import 'package:collection/collection.dart';
+
+abstract class FileStateFilter {
+  /// Return a filter of files that can be accessed by the [file].
+  factory FileStateFilter(FileState file) {
+    var workspacePackage = file.workspacePackage;
+    if (workspacePackage is PubWorkspacePackage) {
+      return _PubFilter(workspacePackage, file.path);
+    } else {
+      return _AnyFilter();
+    }
+  }
+
+  bool shouldInclude(FileState file);
+}
+
+class _AnyFilter implements FileStateFilter {
+  @override
+  bool shouldInclude(FileState file) => true;
+}
+
+class _PubFilter implements FileStateFilter {
+  final PubWorkspacePackage targetPackage;
+  final String? targetPackageName;
+  final bool targetInLib;
+  final Set<String> dependencies;
+
+  factory _PubFilter(PubWorkspacePackage package, String path) {
+    var inLib = package.workspace.provider
+        .getFolder(package.root)
+        .getChildAssumingFolder('lib')
+        .contains(path);
+
+    var dependencies = <String>{};
+    var pubspec = package.pubspec;
+    if (pubspec != null) {
+      dependencies.addAll(pubspec.dependencies.names);
+      if (!inLib) {
+        dependencies.addAll(pubspec.devDependencies.names);
+      }
+    }
+
+    return _PubFilter._(
+      targetPackage: package,
+      targetPackageName: pubspec?.name?.value.text,
+      targetInLib: inLib,
+      dependencies: dependencies,
+    );
+  }
+
+  _PubFilter._({
+    required this.targetPackage,
+    required this.targetPackageName,
+    required this.targetInLib,
+    required this.dependencies,
+  });
+
+  @override
+  bool shouldInclude(FileState file) {
+    var uri = file.uriProperties;
+    if (uri.isDart) {
+      return true;
+    }
+
+    // Normally only package URIs are available.
+    // But outside of lib/ we allow any files of this package.
+    var packageName = uri.packageName;
+    if (packageName == null) {
+      if (targetInLib) {
+        return false;
+      } else {
+        var filePackage = file.workspacePackage;
+        return filePackage is PubWorkspacePackage &&
+            filePackage.root == targetPackage.root;
+      }
+    }
+
+    // Any `package:` library from the same package.
+    if (packageName == targetPackageName) {
+      return true;
+    }
+
+    // If not the same package, must be public.
+    if (uri.isSrc) {
+      return false;
+    }
+
+    return dependencies.contains(packageName);
+  }
+}
+
+extension on PSDependencyList? {
+  List<String> get names {
+    final self = this;
+    if (self == null) {
+      return const [];
+    } else {
+      return self
+          .map((dependency) => dependency.name?.text)
+          .whereNotNull()
+          .toList();
+    }
+  }
+}
diff --git a/pkg/analyzer/lib/src/dart/analysis/index.dart b/pkg/analyzer/lib/src/dart/analysis/index.dart
index e3b952f..9ce7dda 100644
--- a/pkg/analyzer/lib/src/dart/analysis/index.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/index.dart
@@ -596,6 +596,8 @@
           return;
         }
       }
+    } else if (expression is PropertyAccess) {
+      // Nothing to do?
     } else {
       throw UnimplementedError('Unhandled CommentReference expression type: '
           '${expression.runtimeType}');
diff --git a/pkg/analyzer/lib/src/dart/analysis/library_analyzer.dart b/pkg/analyzer/lib/src/dart/analysis/library_analyzer.dart
index beabb03..0b49b4e 100644
--- a/pkg/analyzer/lib/src/dart/analysis/library_analyzer.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/library_analyzer.dart
@@ -451,18 +451,15 @@
   }
 
   void _computeVerifyErrors(FileState file, CompilationUnit unit) {
-    RecordingErrorListener errorListener = _getErrorListener(file);
+    ErrorReporter errorReporter = _getErrorReporter(file);
 
     CodeChecker checker = CodeChecker(
       _typeProvider,
       _typeSystem,
-      _inheritance,
-      errorListener,
+      errorReporter,
     );
     checker.visitCompilationUnit(unit);
 
-    ErrorReporter errorReporter = _getErrorReporter(file);
-
     //
     // Validate the directives.
     //
@@ -783,7 +780,7 @@
     }
 
     var absoluteUri = resolveRelativeUri(_library.uri, relativeUri);
-    return rewriteFileToPackageUri(_sourceFactory, absoluteUri);
+    return rewriteToCanonicalUri(_sourceFactory, absoluteUri);
   }
 
   /// Return the result of resolve the given [uriContent], reporting errors
diff --git a/pkg/analyzer/lib/src/dart/analysis/results.dart b/pkg/analyzer/lib/src/dart/analysis/results.dart
index a8184db..e799e6d 100644
--- a/pkg/analyzer/lib/src/dart/analysis/results.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/results.dart
@@ -16,15 +16,7 @@
   @override
   final AnalysisSession session;
 
-  @Deprecated('Use FileResult.path instead')
-  @override
-  final String path;
-
-  @Deprecated('Use FileResult.uri instead')
-  @override
-  final Uri uri;
-
-  AnalysisResultImpl(this.session, this.path, this.uri);
+  AnalysisResultImpl(this.session);
 }
 
 class ElementDeclarationResultImpl implements ElementDeclarationResult {
@@ -55,28 +47,20 @@
 
 class FileResultImpl extends AnalysisResultImpl implements FileResult {
   @override
+  final String path;
+
+  @override
+  final Uri uri;
+
+  @override
   final LineInfo lineInfo;
 
   @override
   final bool isPart;
 
   FileResultImpl(
-      AnalysisSession session, String path, Uri uri, this.lineInfo, this.isPart)
-      : super(session, path, uri);
-
-  @override
-  // TODO(scheglov) Convert into a field.
-  // ignore: deprecated_member_use_from_same_package, unnecessary_overrides
-  String get path => super.path;
-
-  @Deprecated('Check for specific Result subtypes instead')
-  @override
-  ResultState get state => ResultState.VALID;
-
-  @override
-  // TODO(scheglov) Convert into a field.
-  // ignore: deprecated_member_use_from_same_package, unnecessary_overrides
-  Uri get uri => super.uri;
+      AnalysisSession session, this.path, this.uri, this.lineInfo, this.isPart)
+      : super(session);
 }
 
 class LibraryElementResultImpl implements LibraryElementResult {
@@ -91,15 +75,7 @@
   @override
   final List<ParsedUnitResult> units;
 
-  ParsedLibraryResultImpl(
-      AnalysisSession session, String path, Uri uri, this.units)
-      : super(session, path, uri);
-
-  @Deprecated('Check for specific Result subtypes instead')
-  @override
-  ResultState get state {
-    return ResultState.VALID;
-  }
+  ParsedLibraryResultImpl(AnalysisSession session, this.units) : super(session);
 
   @override
   ElementDeclarationResult? getElementDeclaration(Element element) {
@@ -145,10 +121,6 @@
   ParsedUnitResultImpl(AnalysisSession session, String path, Uri uri,
       this.content, LineInfo lineInfo, bool isPart, this.unit, this.errors)
       : super(session, path, uri, lineInfo, isPart);
-
-  @Deprecated('Check for specific Result subtypes instead')
-  @override
-  ResultState get state => ResultState.VALID;
 }
 
 class ParseStringResultImpl implements ParseStringResult {
@@ -217,15 +189,8 @@
   @override
   final List<ResolvedUnitResult> units;
 
-  ResolvedLibraryResultImpl(
-      AnalysisSession session, String path, Uri uri, this.element, this.units)
-      : super(session, path, uri);
-
-  @Deprecated('Check for specific Result subtypes instead')
-  @override
-  ResultState get state {
-    return ResultState.VALID;
-  }
+  ResolvedLibraryResultImpl(AnalysisSession session, this.element, this.units)
+      : super(session);
 
   @override
   TypeProvider get typeProvider => element.typeProvider;
@@ -292,10 +257,6 @@
     return unit.declaredElement!.library;
   }
 
-  @Deprecated('Check for specific Result subtypes instead')
-  @override
-  ResultState get state => ResultState.VALID;
-
   @override
   TypeProvider get typeProvider => libraryElement.typeProvider;
 
@@ -306,18 +267,11 @@
 class UnitElementResultImpl extends FileResultImpl
     implements UnitElementResult {
   @override
-  final String signature;
-
-  @override
   final CompilationUnitElement element;
 
   UnitElementResultImpl(AnalysisSession session, String path, Uri uri,
-      LineInfo lineInfo, bool isPart, this.signature, this.element)
+      LineInfo lineInfo, bool isPart, this.element)
       : super(session, path, uri, lineInfo, isPart);
-
-  @Deprecated('Check for specific Result subtypes instead')
-  @override
-  ResultState get state => ResultState.VALID;
 }
 
 class _DeclarationByElementLocator extends GeneralizingAstVisitor<void> {
diff --git a/pkg/analyzer/lib/src/dart/analysis/session.dart b/pkg/analyzer/lib/src/dart/analysis/session.dart
index 6376bc1..32eeaca 100644
--- a/pkg/analyzer/lib/src/dart/analysis/session.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/session.dart
@@ -60,48 +60,24 @@
     return _driver.getErrors(path);
   }
 
-  @Deprecated('Use getErrors() instead')
-  @override
-  Future<SomeErrorsResult> getErrors2(String path) {
-    return getErrors(path);
-  }
-
   @override
   SomeFileResult getFile(String path) {
     _checkConsistency();
     return _driver.getFileSync(path);
   }
 
-  @Deprecated('Use getFile() instead')
-  @override
-  SomeFileResult getFile2(String path) {
-    return getFile(path);
-  }
-
   @override
   Future<SomeLibraryElementResult> getLibraryByUri(String uri) {
     _checkConsistency();
     return _driver.getLibraryByUri(uri);
   }
 
-  @Deprecated('Use getLibraryByUri() instead')
-  @override
-  Future<SomeLibraryElementResult> getLibraryByUri2(String uri) {
-    return getLibraryByUri(uri);
-  }
-
   @override
   SomeParsedLibraryResult getParsedLibrary(String path) {
     _checkConsistency();
     return _driver.getParsedLibrary(path);
   }
 
-  @Deprecated('Use getParsedLibrary() instead')
-  @override
-  SomeParsedLibraryResult getParsedLibrary2(String path) {
-    return getParsedLibrary(path);
-  }
-
   @override
   SomeParsedLibraryResult getParsedLibraryByElement(LibraryElement element) {
     _checkConsistency();
@@ -113,36 +89,18 @@
     return _driver.getParsedLibraryByUri(element.source.uri);
   }
 
-  @Deprecated('Use getParsedLibraryByElement() instead')
-  @override
-  SomeParsedLibraryResult getParsedLibraryByElement2(LibraryElement element) {
-    return getParsedLibraryByElement(element);
-  }
-
   @override
   SomeParsedUnitResult getParsedUnit(String path) {
     _checkConsistency();
     return _driver.parseFileSync(path);
   }
 
-  @Deprecated('Use getParsedUnit() instead')
-  @override
-  SomeParsedUnitResult getParsedUnit2(String path) {
-    return getParsedUnit(path);
-  }
-
   @override
   Future<SomeResolvedLibraryResult> getResolvedLibrary(String path) {
     _checkConsistency();
     return _driver.getResolvedLibrary(path);
   }
 
-  @Deprecated('Use getResolvedLibrary() instead')
-  @override
-  Future<SomeResolvedLibraryResult> getResolvedLibrary2(String path) {
-    return getResolvedLibrary(path);
-  }
-
   @override
   Future<SomeResolvedLibraryResult> getResolvedLibraryByElement(
     LibraryElement element,
@@ -158,38 +116,18 @@
     return _driver.getResolvedLibraryByUri(element.source.uri);
   }
 
-  @Deprecated('Use getResolvedLibraryByElement() instead')
-  @override
-  Future<SomeResolvedLibraryResult> getResolvedLibraryByElement2(
-    LibraryElement element,
-  ) {
-    return getResolvedLibraryByElement(element);
-  }
-
   @override
   Future<SomeResolvedUnitResult> getResolvedUnit(String path) {
     _checkConsistency();
     return _driver.getResult(path);
   }
 
-  @Deprecated('Use getResolvedUnit() instead')
-  @override
-  Future<SomeResolvedUnitResult> getResolvedUnit2(String path) {
-    return getResolvedUnit(path);
-  }
-
   @override
   Future<SomeUnitElementResult> getUnitElement(String path) {
     _checkConsistency();
     return _driver.getUnitElement(path);
   }
 
-  @Deprecated('Use getUnitElement() instead')
-  @override
-  Future<SomeUnitElementResult> getUnitElement2(String path) {
-    return getUnitElement(path);
-  }
-
   /// Check to see that results from this session will be consistent, and throw
   /// an [InconsistentAnalysisException] if they might not be.
   void _checkConsistency() {
diff --git a/pkg/analyzer/lib/src/dart/ast/ast.dart b/pkg/analyzer/lib/src/dart/ast/ast.dart
index 3ab0730..ca91eb4 100644
--- a/pkg/analyzer/lib/src/dart/ast/ast.dart
+++ b/pkg/analyzer/lib/src/dart/ast/ast.dart
@@ -16,7 +16,6 @@
 import 'package:analyzer/src/dart/ast/to_source_visitor.dart';
 import 'package:analyzer/src/dart/ast/token.dart';
 import 'package:analyzer/src/fasta/token_utils.dart' as util show findPrevious;
-import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/source.dart' show LineInfo, Source;
 import 'package:analyzer/src/generated/utilities_dart.dart';
 
@@ -784,7 +783,9 @@
   }
 
   @override
-  E? thisOrAncestorMatching<E extends AstNode>(Predicate<AstNode> predicate) {
+  E? thisOrAncestorMatching<E extends AstNode>(
+    bool Function(AstNode) predicate,
+  ) {
     AstNode? node = this;
     while (node != null && !predicate(node)) {
       node = node.parent;
@@ -1394,6 +1395,10 @@
   @override
   Token? abstractKeyword;
 
+  /// The 'macro' keyword, or `null` if the keyword was absent.
+  @override
+  Token? macroKeyword;
+
   /// The token representing the 'class' keyword.
   @override
   Token classKeyword;
@@ -1422,6 +1427,7 @@
       CommentImpl? comment,
       List<Annotation>? metadata,
       this.abstractKeyword,
+      this.macroKeyword,
       this.classKeyword,
       SimpleIdentifierImpl name,
       TypeParameterListImpl? typeParameters,
@@ -1440,6 +1446,7 @@
   @override
   Iterable<SyntacticEntity> get childEntities => super._childEntities
     ..add(abstractKeyword)
+    ..add(macroKeyword)
     ..add(classKeyword)
     ..add(_name)
     ..add(_typeParameters)
@@ -1463,7 +1470,7 @@
 
   @override
   Token get firstTokenAfterCommentAndMetadata {
-    return abstractKeyword ?? classKeyword;
+    return abstractKeyword ?? macroKeyword ?? classKeyword;
   }
 
   @override
@@ -1643,6 +1650,11 @@
   @override
   Token? abstractKeyword;
 
+  /// The token for the 'macro' keyword, or `null` if this is not defining a
+  /// macro class.
+  @override
+  Token? macroKeyword;
+
   /// The name of the superclass of the class being declared.
   NamedTypeImpl _superclass;
 
@@ -1667,6 +1679,7 @@
       this._typeParameters,
       this.equals,
       this.abstractKeyword,
+      this.macroKeyword,
       this._superclass,
       this._withClause,
       this._implementsClause,
@@ -1685,6 +1698,7 @@
     ..add(_typeParameters)
     ..add(equals)
     ..add(abstractKeyword)
+    ..add(macroKeyword)
     ..add(_superclass)
     ..add(_withClause)
     ..add(_implementsClause)
@@ -1695,7 +1709,7 @@
 
   @override
   Token get firstTokenAfterCommentAndMetadata {
-    return abstractKeyword ?? typedefKeyword;
+    return abstractKeyword ?? macroKeyword ?? typedefKeyword;
   }
 
   @override
@@ -1709,10 +1723,6 @@
   @override
   bool get isAbstract => abstractKeyword != null;
 
-  @Deprecated('Use superclass2 instead')
-  @override
-  NamedTypeImpl get superclass => _superclass;
-
   set superclass(NamedType superclass) {
     _superclass = _becomeParentOf(superclass as NamedTypeImpl);
   }
@@ -2654,10 +2664,6 @@
     _name = _becomeParentOf(name as SimpleIdentifierImpl?);
   }
 
-  @Deprecated('Use type2 instead')
-  @override
-  NamedTypeImpl get type => _type;
-
   set type(NamedType type) {
     _type = _becomeParentOf(type as NamedTypeImpl);
   }
@@ -3286,14 +3292,27 @@
 /// The declaration of an enumeration.
 ///
 ///    enumType ::=
-///        metadata 'enum' [SimpleIdentifier] '{' [SimpleIdentifier]
-///        (',' [SimpleIdentifier])* (',')? '}'
+///        metadata 'enum' [SimpleIdentifier] [TypeParameterList]?
+///        [WithClause]? [ImplementsClause]? '{' [SimpleIdentifier]
+///        (',' [SimpleIdentifier])* (';' [ClassMember]+)? '}'
 class EnumDeclarationImpl extends NamedCompilationUnitMemberImpl
     implements EnumDeclaration {
   /// The 'enum' keyword.
   @override
   Token enumKeyword;
 
+  /// The type parameters, or `null` if the enumeration does not have any
+  /// type parameters.
+  TypeParameterListImpl? _typeParameters;
+
+  /// The `with` clause for the enumeration, or `null` if the class does not
+  /// have a `with` clause.
+  WithClauseImpl? _withClause;
+
+  /// The `implements` clause for the enumeration, or `null` if the enumeration
+  /// does not implement any interfaces.
+  ImplementsClauseImpl? _implementsClause;
+
   /// The left curly bracket.
   @override
   Token leftBracket;
@@ -3317,11 +3336,17 @@
       List<Annotation>? metadata,
       this.enumKeyword,
       SimpleIdentifierImpl name,
+      this._typeParameters,
+      this._withClause,
+      this._implementsClause,
       this.leftBracket,
       List<EnumConstantDeclaration> constants,
       List<ClassMember> members,
       this.rightBracket)
       : super(comment, metadata, name) {
+    _becomeParentOf(_typeParameters);
+    _becomeParentOf(_withClause);
+    _becomeParentOf(_implementsClause);
     _constants._initialize(this, constants);
     _members._initialize(this, members);
   }
@@ -3331,6 +3356,9 @@
   Iterable<SyntacticEntity> get childEntities => super._childEntities
     ..add(enumKeyword)
     ..add(_name)
+    ..add(_typeParameters)
+    ..add(_withClause)
+    ..add(_implementsClause)
     ..add(leftBracket)
     ..addAll(_constants)
     ..addAll(_members)
@@ -3349,15 +3377,40 @@
   Token get firstTokenAfterCommentAndMetadata => enumKeyword;
 
   @override
+  ImplementsClauseImpl? get implementsClause => _implementsClause;
+
+  set implementsClause(ImplementsClause? implementsClause) {
+    _implementsClause =
+        _becomeParentOf(implementsClause as ImplementsClauseImpl?);
+  }
+
+  @override
   NodeListImpl<ClassMember> get members => _members;
 
   @override
+  TypeParameterListImpl? get typeParameters => _typeParameters;
+
+  set typeParameters(TypeParameterList? typeParameters) {
+    _typeParameters = _becomeParentOf(typeParameters as TypeParameterListImpl?);
+  }
+
+  @override
+  WithClauseImpl? get withClause => _withClause;
+
+  set withClause(WithClause? withClause) {
+    _withClause = _becomeParentOf(withClause as WithClauseImpl?);
+  }
+
+  @override
   E? accept<E>(AstVisitor<E> visitor) => visitor.visitEnumDeclaration(this);
 
   @override
   void visitChildren(AstVisitor visitor) {
     super.visitChildren(visitor);
     _name.accept(visitor);
+    _typeParameters?.accept(visitor);
+    _withClause?.accept(visitor);
+    _implementsClause?.accept(visitor);
     _constants.accept(visitor);
     _members.accept(visitor);
   }
@@ -3678,10 +3731,6 @@
   @override
   Token get endToken => _superclass.endToken;
 
-  @Deprecated('Use superclass2 instead')
-  @override
-  NamedTypeImpl get superclass => _superclass;
-
   set superclass(NamedType name) {
     _superclass = _becomeParentOf(name as NamedTypeImpl);
   }
@@ -5810,10 +5859,6 @@
   @override
   Token get endToken => _interfaces.endToken!;
 
-  @Deprecated('Use interfaces2 instead')
-  @override
-  NodeList<TypeName> get interfaces => _DelegatingTypeNameList(_interfaces);
-
   @override
   NodeListImpl<NamedType> get interfaces2 => _interfaces;
 
@@ -7469,7 +7514,7 @@
 ///    typeName ::=
 ///        [Identifier] typeArguments? '?'?
 /// ignore: deprecated_member_use_from_same_package
-class NamedTypeImpl extends TypeAnnotationImpl implements TypeName {
+class NamedTypeImpl extends TypeAnnotationImpl implements NamedType {
   /// The name of the type.
   IdentifierImpl _name;
 
@@ -8019,11 +8064,6 @@
   @override
   Token get endToken => _superclassConstraints.endToken!;
 
-  @Deprecated('Use superclassConstraints2 instead')
-  @override
-  NodeList<TypeName> get superclassConstraints =>
-      _DelegatingTypeNameList(_superclassConstraints);
-
   @override
   NodeListImpl<NamedType> get superclassConstraints2 => _superclassConstraints;
 
@@ -9310,12 +9350,11 @@
   Token literal;
 
   /// The value of the literal.
-  String _value;
+  @override
+  String value;
 
   /// Initialize a newly created simple string literal.
-  SimpleStringLiteralImpl(this.literal, this._value) {
-    _value = StringUtilities.intern(value);
-  }
+  SimpleStringLiteralImpl(this.literal, this.value);
 
   @override
   Token get beginToken => literal;
@@ -9344,13 +9383,6 @@
   @override
   bool get isSynthetic => literal.isSynthetic;
 
-  @override
-  String get value => _value;
-
-  set value(String string) {
-    _value = StringUtilities.intern(_value);
-  }
-
   StringLexemeHelper get _helper {
     return StringLexemeHelper(literal.lexeme, true, true);
   }
@@ -9553,12 +9585,12 @@
       if (isRaw) {
         start++;
       }
-      if (StringUtilities.startsWith3(lexeme, start, 0x27, 0x27, 0x27)) {
+      if (lexeme.startsWith("'''", start)) {
         isSingleQuoted = true;
         isMultiline = true;
         start += 3;
         start = _trimInitialWhitespace(start);
-      } else if (StringUtilities.startsWith3(lexeme, start, 0x22, 0x22, 0x22)) {
+      } else if (lexeme.startsWith('"""', start)) {
         isSingleQuoted = false;
         isMultiline = true;
         start += 3;
@@ -9576,12 +9608,10 @@
     end = lexeme.length;
     if (isLast) {
       if (start + 3 <= end &&
-          (StringUtilities.endsWith3(lexeme, 0x22, 0x22, 0x22) ||
-              StringUtilities.endsWith3(lexeme, 0x27, 0x27, 0x27))) {
+          (lexeme.endsWith("'''") || lexeme.endsWith('"""'))) {
         end -= 3;
       } else if (start + 1 <= end &&
-          (StringUtilities.endsWithChar(lexeme, 0x22) ||
-              StringUtilities.endsWithChar(lexeme, 0x27))) {
+          (lexeme.endsWith("'") || lexeme.endsWith('"'))) {
         end -= 1;
       }
     }
@@ -10540,10 +10570,6 @@
   @override
   NamedTypeImpl get type => _typeName;
 
-  @Deprecated('Use namedType instead')
-  @override
-  NamedTypeImpl get typeName => _typeName;
-
   set typeName(NamedTypeImpl value) {
     _typeName = _becomeParentOf(value);
   }
@@ -11124,10 +11150,6 @@
   @override
   Token get endToken => _mixinTypes.endToken!;
 
-  @Deprecated('Use mixinTypes2 instead')
-  @override
-  NodeList<TypeName> get mixinTypes => _DelegatingTypeNameList(_mixinTypes);
-
   @override
   NodeListImpl<NamedType> get mixinTypes2 => _mixinTypes;
 
@@ -11200,77 +11222,6 @@
   }
 }
 
-/// Implementation of `NodeList<TypeName>` that delegates.
-@Deprecated('Use NamedType instead')
-class _DelegatingTypeNameList
-    with ListMixin<TypeName>
-    implements NodeList<TypeName> {
-  final NodeListImpl<NamedType> _delegate;
-
-  _DelegatingTypeNameList(this._delegate);
-
-  @override
-  Token? get beginToken {
-    return _delegate.beginToken;
-  }
-
-  @override
-  Token? get endToken {
-    return _delegate.endToken;
-  }
-
-  @override
-  int get length => _delegate.length;
-
-  @override
-  set length(int newLength) {
-    _delegate.length = newLength;
-  }
-
-  @override
-  AstNodeImpl get owner => _delegate.owner;
-
-  @override
-  TypeName operator [](int index) {
-    return _delegate[index] as TypeName;
-  }
-
-  @override
-  void operator []=(int index, TypeName node) {
-    _delegate[index] = node;
-  }
-
-  @override
-  void accept(AstVisitor visitor) {
-    _delegate.accept(visitor);
-  }
-
-  @override
-  void add(NamedType node) {
-    _delegate.add(node);
-  }
-
-  @override
-  void addAll(Iterable<TypeName> nodes) {
-    _delegate.addAll(nodes);
-  }
-
-  @override
-  void clear() {
-    _delegate.clear();
-  }
-
-  @override
-  void insert(int index, TypeName node) {
-    _delegate.insert(index, node);
-  }
-
-  @override
-  TypeName removeAt(int index) {
-    return _delegate.removeAt(index) as TypeName;
-  }
-}
-
 /// An indication of the resolved kind of a [SetOrMapLiteral].
 enum _SetOrMapKind {
   /// Indicates that the literal represents a map.
diff --git a/pkg/analyzer/lib/src/dart/ast/ast_factory.dart b/pkg/analyzer/lib/src/dart/ast/ast_factory.dart
index b7a9b76..806d84e 100644
--- a/pkg/analyzer/lib/src/dart/ast/ast_factory.dart
+++ b/pkg/analyzer/lib/src/dart/ast/ast_factory.dart
@@ -155,6 +155,7 @@
           Comment? comment,
           List<Annotation>? metadata,
           Token? abstractKeyword,
+          Token? macroKeyword,
           Token classKeyword,
           SimpleIdentifier name,
           TypeParameterList? typeParameters,
@@ -168,6 +169,7 @@
           comment as CommentImpl?,
           metadata,
           abstractKeyword,
+          macroKeyword,
           classKeyword,
           name as SimpleIdentifierImpl,
           typeParameters as TypeParameterListImpl?,
@@ -187,6 +189,7 @@
           TypeParameterList? typeParameters,
           Token equals,
           Token? abstractKeyword,
+          Token? macroKeyword,
           NamedType superclass,
           WithClause withClause,
           ImplementsClause? implementsClause,
@@ -199,6 +202,7 @@
           typeParameters as TypeParameterListImpl?,
           equals,
           abstractKeyword,
+          macroKeyword,
           superclass as NamedTypeImpl,
           withClause as WithClauseImpl,
           implementsClause as ImplementsClauseImpl?,
@@ -383,6 +387,7 @@
       EnumConstantDeclarationImpl(
           comment as CommentImpl?, metadata, name as SimpleIdentifierImpl);
 
+  @Deprecated('Use enumDeclaration2() instead')
   @override
   EnumDeclarationImpl enumDeclaration(
           Comment? comment,
@@ -391,17 +396,48 @@
           SimpleIdentifier name,
           Token leftBracket,
           List<EnumConstantDeclaration> constants,
-          List<ClassMember> members,
           Token rightBracket) =>
-      EnumDeclarationImpl(
-          comment as CommentImpl?,
-          metadata,
-          enumKeyword,
-          name as SimpleIdentifierImpl,
-          leftBracket,
-          constants,
-          members,
-          rightBracket);
+      enumDeclaration2(
+          comment: comment,
+          metadata: metadata,
+          enumKeyword: enumKeyword,
+          name: name,
+          typeParameters: null,
+          withClause: null,
+          implementsClause: null,
+          leftBracket: leftBracket,
+          constants: constants,
+          members: [],
+          rightBracket: rightBracket);
+
+  @override
+  EnumDeclarationImpl enumDeclaration2({
+    required Comment? comment,
+    required List<Annotation>? metadata,
+    required Token enumKeyword,
+    required SimpleIdentifier name,
+    required TypeParameterList? typeParameters,
+    required WithClause? withClause,
+    required ImplementsClause? implementsClause,
+    required Token leftBracket,
+    required List<EnumConstantDeclaration> constants,
+    required List<ClassMember> members,
+    required Token rightBracket,
+  }) {
+    return EnumDeclarationImpl(
+      comment as CommentImpl?,
+      metadata,
+      enumKeyword,
+      name as SimpleIdentifierImpl,
+      typeParameters as TypeParameterListImpl?,
+      withClause as WithClauseImpl?,
+      implementsClause as ImplementsClauseImpl?,
+      leftBracket,
+      constants,
+      members,
+      rightBracket,
+    );
+  }
 
   @override
   ExportDirectiveImpl exportDirective(
@@ -1295,14 +1331,6 @@
   TypeLiteralImpl typeLiteral({required NamedType typeName}) =>
       TypeLiteralImpl(typeName as NamedTypeImpl);
 
-  @Deprecated('Use namedType() instead')
-  @override
-  NamedTypeImpl typeName(Identifier name, TypeArgumentList? typeArguments,
-          {Token? question}) =>
-      NamedTypeImpl(
-          name as IdentifierImpl, typeArguments as TypeArgumentListImpl?,
-          question: question);
-
   @override
   TypeParameterImpl typeParameter(
           Comment? comment,
diff --git a/pkg/analyzer/lib/src/dart/ast/extensions.dart b/pkg/analyzer/lib/src/dart/ast/extensions.dart
index 3df0bb6..f30fcca 100644
--- a/pkg/analyzer/lib/src/dart/ast/extensions.dart
+++ b/pkg/analyzer/lib/src/dart/ast/extensions.dart
@@ -118,14 +118,14 @@
 
 /// TODO(scheglov) https://github.com/dart-lang/sdk/issues/43608
 extension IdentifierExtension on Identifier {
-  Element? get writeElement {
-    return _writeElement(this);
-  }
-
   Element? get readElement {
     return _readElement(this);
   }
 
+  Element? get writeElement {
+    return _writeElement(this);
+  }
+
   Element? get writeOrReadElement {
     return _writeElement(this) ?? staticElement;
   }
diff --git a/pkg/analyzer/lib/src/dart/ast/to_source_visitor.dart b/pkg/analyzer/lib/src/dart/ast/to_source_visitor.dart
index 49dff85..294a89f 100644
--- a/pkg/analyzer/lib/src/dart/ast/to_source_visitor.dart
+++ b/pkg/analyzer/lib/src/dart/ast/to_source_visitor.dart
@@ -151,6 +151,7 @@
   void visitClassDeclaration(ClassDeclaration node) {
     _visitNodeList(node.metadata, separator: ' ', suffix: ' ');
     _visitToken(node.abstractKeyword, suffix: ' ');
+    _visitToken(node.macroKeyword, suffix: ' ');
     sink.write('class ');
     _visitNode(node.name);
     _visitNode(node.typeParameters);
@@ -168,6 +169,7 @@
     if (node.abstractKeyword != null) {
       sink.write('abstract ');
     }
+    _visitToken(node.macroKeyword, suffix: ' ');
     sink.write('class ');
     _visitNode(node.name);
     _visitNode(node.typeParameters);
@@ -314,8 +316,12 @@
     _visitNodeList(node.metadata, separator: ' ', suffix: ' ');
     sink.write('enum ');
     _visitNode(node.name);
+    _visitNode(node.typeParameters);
+    _visitNode(node.withClause, prefix: ' ');
+    _visitNode(node.implementsClause, prefix: ' ');
     sink.write(' {');
     _visitNodeList(node.constants, separator: ', ');
+    _visitNodeList(node.members, prefix: '; ', separator: ' ');
     sink.write('}');
   }
 
@@ -1039,12 +1045,6 @@
     _visitNode(node.type);
   }
 
-  @Deprecated('Override visitNamedType instead')
-  @override
-  void visitTypeName(TypeName node) {
-    throw StateError('Should not be invoked');
-  }
-
   @override
   void visitTypeParameter(TypeParameter node) {
     _visitNodeList(node.metadata, separator: ' ', suffix: ' ');
diff --git a/pkg/analyzer/lib/src/dart/ast/utilities.dart b/pkg/analyzer/lib/src/dart/ast/utilities.dart
index 3bbe4f6..4db6958 100644
--- a/pkg/analyzer/lib/src/dart/ast/utilities.dart
+++ b/pkg/analyzer/lib/src/dart/ast/utilities.dart
@@ -9,7 +9,6 @@
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/exception/exception.dart';
 import 'package:analyzer/src/dart/ast/ast.dart';
-import 'package:analyzer/src/dart/ast/to_source_visitor.dart';
 import 'package:analyzer/src/dart/element/element.dart';
 import 'package:analyzer/src/generated/engine.dart' show AnalysisEngine;
 
@@ -1201,12 +1200,6 @@
     return isEqualNodes(node.type, other.type);
   }
 
-  @Deprecated('Override visitNamedType instead')
-  @override
-  bool visitTypeName(TypeName node) {
-    throw StateError('Should not be invoked');
-  }
-
   @override
   bool visitTypeParameter(TypeParameter node) {
     TypeParameter other = _other as TypeParameter;
@@ -2002,8 +1995,19 @@
     if (identical(node.name, _oldNode)) {
       node.name = _newNode as SimpleIdentifier;
       return true;
+    } else if (identical(node.typeParameters, _oldNode)) {
+      node.typeParameters = _newNode as TypeParameterList;
+      return true;
+    } else if (identical(node.withClause, _oldNode)) {
+      node.withClause = _newNode as WithClause;
+      return true;
+    } else if (identical(node.implementsClause, _oldNode)) {
+      node.implementsClause = _newNode as ImplementsClause;
+      return true;
     } else if (_replaceInList(node.constants)) {
       return true;
+    } else if (_replaceInList(node.members)) {
+      return true;
     }
     return visitAnnotatedNode(node);
   }
@@ -2091,6 +2095,9 @@
     if (identical(node.type, _oldNode)) {
       node.type = _newNode as TypeAnnotation;
       return true;
+    } else if (identical(node.typeParameters, _oldNode)) {
+      node.typeParameters = _newNode as TypeParameterList;
+      return true;
     } else if (identical(node.parameters, _oldNode)) {
       node.parameters = _newNode as FormalParameterList;
       return true;
@@ -2217,6 +2224,9 @@
     if (identical(node.parameters, _oldNode)) {
       node.parameters = _newNode as FormalParameterList;
       return true;
+    } else if (identical(node.typeParameters, _oldNode)) {
+      node.typeParameters = _newNode as TypeParameterList;
+      return true;
     } else if (identical(node.body, _oldNode)) {
       node.body = _newNode as FunctionBody;
       return true;
@@ -2233,6 +2243,9 @@
     } else if (identical(node.argumentList, _oldNode)) {
       node.argumentList = _newNode as ArgumentList;
       return true;
+    } else if (identical(node.typeArguments, _oldNode)) {
+      node.typeArguments = _newNode as TypeArgumentList;
+      return true;
     }
     return visitNode(node);
   }
@@ -2276,6 +2289,9 @@
     } else if (identical(node.parameters, _oldNode)) {
       node.parameters = _newNode as FormalParameterList;
       return true;
+    } else if (identical(node.typeParameters, _oldNode)) {
+      node.typeParameters = _newNode as TypeParameterList;
+      return true;
     }
     return visitNormalFormalParameter(node);
   }
@@ -2509,6 +2525,9 @@
     } else if (identical(node.parameters, _oldNode)) {
       node.parameters = _newNode as FormalParameterList;
       return true;
+    } else if (identical(node.typeParameters, _oldNode)) {
+      node.typeParameters = _newNode as TypeParameterList;
+      return true;
     } else if (identical(node.body, _oldNode)) {
       node.body = _newNode as FunctionBody;
       return true;
@@ -2527,6 +2546,9 @@
     } else if (identical(node.argumentList, _oldNode)) {
       node.argumentList = _newNode as ArgumentList;
       return true;
+    } else if (identical(node.typeArguments, _oldNode)) {
+      node.typeArguments = _newNode as TypeArgumentList;
+      return true;
     }
     return visitNode(node);
   }
@@ -2921,11 +2943,6 @@
   }
 
   @override
-  bool visitTypeName(covariant NamedTypeImpl node) {
-    throw StateError('Should not be invoked');
-  }
-
-  @override
   bool visitTypeParameter(covariant TypeParameterImpl node) {
     if (identical(node.name, _oldNode)) {
       node.name = _newNode as SimpleIdentifier;
@@ -3217,10 +3234,3 @@
     return node.end < _position;
   }
 }
-
-/// A visitor used to write a source representation of a visited AST node (and
-/// all of it's children) to a sink.
-@Deprecated('Use ToSourceVisitor')
-class ToSourceVisitor2 extends ToSourceVisitor {
-  ToSourceVisitor2(StringSink sink) : super(sink);
-}
diff --git a/pkg/analyzer/lib/src/dart/constant/evaluation.dart b/pkg/analyzer/lib/src/dart/constant/evaluation.dart
index 3e230c6..514d859 100644
--- a/pkg/analyzer/lib/src/dart/constant/evaluation.dart
+++ b/pkg/analyzer/lib/src/dart/constant/evaluation.dart
@@ -220,7 +220,7 @@
           if (superclass != null && !superclass.isDartCoreObject) {
             var unnamedConstructor =
                 superclass.element.unnamedConstructor?.declaration;
-            if (unnamedConstructor != null) {
+            if (unnamedConstructor != null && unnamedConstructor.isConst) {
               callback(unnamedConstructor);
             }
           }
@@ -612,22 +612,20 @@
     }
 
     var conditionResultBool = conditionResult.toBoolValue();
-    if (conditionResultBool == null) {
-      node.thenExpression.accept(this);
-      node.elseExpression.accept(this);
-    } else if (conditionResultBool == true) {
+    if (conditionResultBool == true) {
       _reportNotPotentialConstants(node.elseExpression);
       return node.thenExpression.accept(this);
     } else if (conditionResultBool == false) {
       _reportNotPotentialConstants(node.thenExpression);
       return node.elseExpression.accept(this);
+    } else {
+      node.thenExpression.accept(this);
+      node.elseExpression.accept(this);
+      return DartObjectImpl.validWithUnknownValue(
+        typeSystem,
+        node.typeOrThrow,
+      );
     }
-
-    // We used to return an object with a known type and an unknown value, but
-    // we can't do that without evaluating both the 'then' and 'else'
-    // expressions, and we're not suppose to do that under lazy semantics. I'm
-    // not sure which failure mode is worse.
-    return null;
   }
 
   @override
diff --git a/pkg/analyzer/lib/src/dart/constant/utilities.dart b/pkg/analyzer/lib/src/dart/constant/utilities.dart
index 4882359..62f7b47 100644
--- a/pkg/analyzer/lib/src/dart/constant/utilities.dart
+++ b/pkg/analyzer/lib/src/dart/constant/utilities.dart
@@ -172,7 +172,7 @@
   void visitInstanceCreationExpression(InstanceCreationExpression node) {
     if (node.isConst) {
       var constructor = node.constructorName.staticElement?.declaration;
-      if (constructor != null) {
+      if (constructor != null && constructor.isConst) {
         _callback(constructor);
       }
     }
diff --git a/pkg/analyzer/lib/src/dart/constant/value.dart b/pkg/analyzer/lib/src/dart/constant/value.dart
index 313caf6..b6c4de1 100644
--- a/pkg/analyzer/lib/src/dart/constant/value.dart
+++ b/pkg/analyzer/lib/src/dart/constant/value.dart
@@ -165,7 +165,7 @@
   /// Create an object to represent an unknown value.
   factory DartObjectImpl.validWithUnknownValue(
     TypeSystemImpl typeSystem,
-    ParameterizedType type,
+    DartType type,
   ) {
     if (type.element!.library!.isDartCore) {
       if (type.isDartCoreBool) {
diff --git a/pkg/analyzer/lib/src/dart/element/element.dart b/pkg/analyzer/lib/src/dart/element/element.dart
index d491590..43e9949 100644
--- a/pkg/analyzer/lib/src/dart/element/element.dart
+++ b/pkg/analyzer/lib/src/dart/element/element.dart
@@ -35,7 +35,6 @@
 import 'package:analyzer/src/dart/resolver/variance.dart';
 import 'package:analyzer/src/generated/element_type_provider.dart';
 import 'package:analyzer/src/generated/engine.dart' show AnalysisContext;
-import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/sdk.dart' show DartSdk;
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/utilities_collection.dart';
@@ -44,6 +43,7 @@
 import 'package:analyzer/src/summary2/bundle_reader.dart';
 import 'package:analyzer/src/summary2/reference.dart';
 import 'package:analyzer/src/task/inference_error.dart';
+import 'package:collection/collection.dart';
 
 /// A concrete implementation of a [ClassElement].
 abstract class AbstractClassElementImpl extends _ExistingElementImpl
@@ -390,7 +390,7 @@
     // TODO (jwren) revisit- should we append '=' here or require clients to
     // include it?
     // Do we need the check for isSetter below?
-    if (!StringUtilities.endsWithChar(setterName, 0x3D)) {
+    if (!setterName.endsWith('=')) {
       setterName += '=';
     }
     for (PropertyAccessorElement accessor in accessors) {
@@ -926,6 +926,9 @@
         implicitConstructor.parameters = implicitParameters;
       }
       implicitConstructor.enclosingElement = this;
+      // TODO(scheglov) Why do we manually map parameters types above?
+      implicitConstructor.superConstructor =
+          ConstructorMember.from(superclassConstructor, supertype!);
 
       var isNamed = superclassConstructor.name.isNotEmpty;
       implicitConstructor.constantInitializers = [
@@ -1297,6 +1300,9 @@
   bool get hasInitializer => false;
 
   @override
+  bool get isEnumConstant => true;
+
+  @override
   Element get nonSynthetic => this;
 
   @override
@@ -1409,6 +1415,14 @@
 class ConstructorElementImpl extends ExecutableElementImpl
     with ConstructorElementMixin
     implements ConstructorElement {
+  /// The super-constructor which this constructor is invoking, or `null` if
+  /// this constructor is not generative, or is redirecting, or the
+  /// super-constructor is not resolved, or the enclosing class is `Object`.
+  ///
+  /// TODO(scheglov) We cannot have both super and redirecting constructors.
+  /// So, ideally we should have some kind of "either" or "variant" here.
+  ConstructorElement? _superConstructor;
+
   /// The constructor to which this constructor is redirecting.
   ConstructorElement? _redirectedConstructor;
 
@@ -1539,6 +1553,15 @@
     return (_returnType ??= enclosingElement.thisType) as InterfaceType;
   }
 
+  ConstructorElement? get superConstructor {
+    linkedData?.read(this);
+    return _superConstructor;
+  }
+
+  set superConstructor(ConstructorElement? superConstructor) {
+    _superConstructor = superConstructor;
+  }
+
   @override
   FunctionType get type => ElementTypeProvider.current.getExecutableType(this);
 
@@ -1648,8 +1671,17 @@
   /// of this variable could not be computed because of errors.
   DartObject? computeConstantValue() {
     if (evaluationResult == null) {
-      computeConstants(library!.typeProvider, library!.typeSystem,
-          context.declaredVariables, [this], library!.featureSet);
+      final library = this.library;
+      // TODO(scheglov) https://github.com/dart-lang/sdk/issues/47915
+      if (library == null) {
+        throw StateError(
+          '[library: null][this: ($runtimeType) $this]'
+          '[enclosingElement: $enclosingElement]'
+          '[reference: $reference]',
+        );
+      }
+      computeConstants(library.typeProvider, library.typeSystem,
+          context.declaredVariables, [this], library.featureSet);
     }
     return evaluationResult?.value;
   }
@@ -1697,6 +1729,26 @@
   }
 }
 
+class DefaultSuperFormalParameterElementImpl
+    extends SuperFormalParameterElementImpl with ConstVariableElement {
+  /// Initialize a newly created parameter element to have the given [name] and
+  /// [nameOffset].
+  DefaultSuperFormalParameterElementImpl({
+    required String name,
+    required int nameOffset,
+    required ParameterKind parameterKind,
+  }) : super(
+          name: name,
+          nameOffset: nameOffset,
+          parameterKind: parameterKind,
+        );
+
+  @override
+  String? get defaultValueCode {
+    return constantInitializer?.toSource();
+  }
+}
+
 /// The synthetic element representing the declaration of the type `dynamic`.
 class DynamicElementImpl extends ElementImpl implements TypeDefiningElement {
   /// Return the unique instance of this class.
@@ -2082,8 +2134,7 @@
 
   /// Initialize a newly created element to have the given [name] at the given
   /// [_nameOffset].
-  ElementImpl(String? name, this._nameOffset, {this.reference}) {
-    _name = name != null ? StringUtilities.intern(name) : null;
+  ElementImpl(this._name, this._nameOffset, {this.reference}) {
     reference?.element = this;
   }
 
@@ -2550,7 +2601,9 @@
   }
 
   @override
-  E thisOrAncestorMatching<E extends Element>(Predicate<Element> predicate) {
+  E thisOrAncestorMatching<E extends Element>(
+    bool Function(Element) predicate,
+  ) {
     Element? element = this;
     while (element != null && !predicate(element)) {
       element = element.enclosingElement;
@@ -2787,10 +2840,7 @@
   bool get hasStaticMember => true;
 
   @override
-  List<InterfaceType> get interfaces {
-    var enumType = library.typeProvider.enumType;
-    return enumType != null ? <InterfaceType>[enumType] : const [];
-  }
+  List<InterfaceType> get interfaces => const [];
 
   @override
   bool get isAbstract => false;
@@ -2831,7 +2881,10 @@
   }
 
   @override
-  InterfaceType get supertype => library.typeProvider.objectType;
+  InterfaceType get supertype {
+    var enumType = library.typeProvider.enumType;
+    return enumType ?? library.typeProvider.objectType;
+  }
 
   @override
   List<TypeParameterElement> get typeParameters =>
@@ -3284,10 +3337,7 @@
   }
 
   @override
-  bool get isEnumConstant =>
-      enclosingElement is ClassElement &&
-      (enclosingElement as ClassElement).isEnum &&
-      !isSynthetic;
+  bool get isEnumConstant => false;
 
   @override
   bool get isExternal {
@@ -4617,8 +4667,11 @@
   }
 
   @override
-  E? thisOrAncestorMatching<E extends Element>(Predicate<Element> predicate) =>
-      null;
+  E? thisOrAncestorMatching<E extends Element>(
+    bool Function(Element) predicate,
+  ) {
+    return null;
+  }
 
   @override
   E? thisOrAncestorOfType<E extends Element>() => null;
@@ -4723,8 +4776,8 @@
   @override
   final ParameterKind parameterKind;
 
-  /// The Dart code of the default value.
-  String? _defaultValueCode;
+  @override
+  String? defaultValueCode;
 
   /// True if this parameter inherits from a covariant parameter. This happens
   /// when it overrides a method in a supertype that has a corresponding
@@ -4756,18 +4809,6 @@
   ParameterElement get declaration => this;
 
   @override
-  String? get defaultValueCode {
-    return _defaultValueCode;
-  }
-
-  /// Set Dart code of the default value.
-  set defaultValueCode(String? defaultValueCode) {
-    _defaultValueCode = defaultValueCode != null
-        ? StringUtilities.intern(defaultValueCode)
-        : null;
-  }
-
-  @override
   bool get hasDefaultValue {
     return defaultValueCode != null;
   }
@@ -4798,6 +4839,9 @@
   bool get isLate => false;
 
   @override
+  bool get isSuperFormal => false;
+
+  @override
   ElementKind get kind => ElementKind.PARAMETER;
 
   @override
@@ -5411,6 +5455,56 @@
   }
 }
 
+class SuperFormalParameterElementImpl extends ParameterElementImpl
+    implements SuperFormalParameterElement {
+  /// Initialize a newly created parameter element to have the given [name] and
+  /// [nameOffset].
+  SuperFormalParameterElementImpl({
+    required String name,
+    required int nameOffset,
+    required ParameterKind parameterKind,
+  }) : super(
+          name: name,
+          nameOffset: nameOffset,
+          parameterKind: parameterKind,
+        );
+
+  /// Super parameters are visible only in the initializer list scope,
+  /// and introduce final variables.
+  @override
+  bool get isFinal => true;
+
+  @override
+  bool get isSuperFormal => true;
+
+  @override
+  ParameterElement? get superConstructorParameter {
+    final enclosingElement = this.enclosingElement;
+    if (enclosingElement is ConstructorElementImpl) {
+      var superConstructor = enclosingElement.superConstructor;
+      if (superConstructor != null) {
+        var superParameters = superConstructor.parameters;
+        if (isNamed) {
+          return superParameters.firstWhereOrNull((e) => e.name == name);
+        } else {
+          var index = enclosingElement.parameters
+              .whereType<SuperFormalParameterElementImpl>()
+              .toList()
+              .indexOf(this);
+          if (index >= 0 && index < superParameters.length) {
+            return superParameters[index];
+          }
+        }
+      }
+    }
+    return null;
+  }
+
+  @override
+  T? accept<T>(ElementVisitor<T> visitor) =>
+      visitor.visitSuperFormalParameterElement(this);
+}
+
 /// A concrete implementation of a [TopLevelVariableElement].
 class TopLevelVariableElementImpl extends PropertyInducingElementImpl
     implements TopLevelVariableElement {
diff --git a/pkg/analyzer/lib/src/dart/element/extensions.dart b/pkg/analyzer/lib/src/dart/element/extensions.dart
index 7037407..ad00f5e 100644
--- a/pkg/analyzer/lib/src/dart/element/extensions.dart
+++ b/pkg/analyzer/lib/src/dart/element/extensions.dart
@@ -60,23 +60,6 @@
 }
 
 extension ElementExtension on Element {
-  /// Return `true` if this element is an instance member of a class or mixin.
-  ///
-  /// Only [MethodElement]s and [PropertyAccessorElement]s are supported.
-  /// We intentionally exclude [ConstructorElement]s - they can only be
-  /// invoked in instance creation expressions, and [FieldElement]s - they
-  /// cannot be invoked directly and are always accessed using corresponding
-  /// [PropertyAccessorElement]s.
-  bool get isInstanceMember {
-    var this_ = this;
-    var enclosing = this_.enclosingElement;
-    if (enclosing is ClassElement) {
-      return this_ is MethodElement && !this_.isStatic ||
-          this_ is PropertyAccessorElement && !this_.isStatic;
-    }
-    return false;
-  }
-
   /// Return `true` if this element, the enclosing class (if there is one), or
   /// the enclosing library, has been annotated with the `@doNotStore`
   /// annotation.
@@ -101,6 +84,23 @@
     return ancestor is CompilationUnitElement &&
         ancestor.enclosingElement.hasDoNotStore;
   }
+
+  /// Return `true` if this element is an instance member of a class or mixin.
+  ///
+  /// Only [MethodElement]s and [PropertyAccessorElement]s are supported.
+  /// We intentionally exclude [ConstructorElement]s - they can only be
+  /// invoked in instance creation expressions, and [FieldElement]s - they
+  /// cannot be invoked directly and are always accessed using corresponding
+  /// [PropertyAccessorElement]s.
+  bool get isInstanceMember {
+    var this_ = this;
+    var enclosing = this_.enclosingElement;
+    if (enclosing is ClassElement) {
+      return this_ is MethodElement && !this_.isStatic ||
+          this_ is PropertyAccessorElement && !this_.isStatic;
+    }
+    return false;
+  }
 }
 
 extension ParameterElementExtensions on ParameterElement {
diff --git a/pkg/analyzer/lib/src/dart/element/member.dart b/pkg/analyzer/lib/src/dart/element/member.dart
index 88dd044..f6195f1 100644
--- a/pkg/analyzer/lib/src/dart/element/member.dart
+++ b/pkg/analyzer/lib/src/dart/element/member.dart
@@ -13,7 +13,6 @@
 import 'package:analyzer/src/dart/element/type_algebra.dart';
 import 'package:analyzer/src/dart/element/type_provider.dart';
 import 'package:analyzer/src/generated/engine.dart' show AnalysisContext;
-import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/utilities_dart.dart';
 
@@ -612,8 +611,11 @@
   }
 
   @override
-  E? thisOrAncestorMatching<E extends Element>(Predicate<Element> predicate) =>
-      declaration.thisOrAncestorMatching(predicate);
+  E? thisOrAncestorMatching<E extends Element>(
+    bool Function(Element) predicate,
+  ) {
+    return declaration.thisOrAncestorMatching(predicate);
+  }
 
   @override
   E? thisOrAncestorOfType<E extends Element>() =>
@@ -840,6 +842,9 @@
   bool get isInitializingFormal => declaration.isInitializingFormal;
 
   @override
+  bool get isSuperFormal => declaration.isSuperFormal;
+
+  @override
   String get name => declaration.name;
 
   @deprecated
diff --git a/pkg/analyzer/lib/src/dart/element/type.dart b/pkg/analyzer/lib/src/dart/element/type.dart
index bb33038..70f398c 100644
--- a/pkg/analyzer/lib/src/dart/element/type.dart
+++ b/pkg/analyzer/lib/src/dart/element/type.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'dart:collection';
-
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/nullability_suffix.dart';
@@ -519,6 +517,11 @@
   }
 
   @override
+  bool get isDartAsyncStream {
+    return element.name == "Stream" && element.library.isDartAsync;
+  }
+
+  @override
   bool get isDartCoreBool {
     return element.name == "bool" && element.library.isDartCore;
   }
@@ -706,17 +709,6 @@
     return ConstructorMember.from(constructorElement, this);
   }
 
-  @deprecated
-  @override
-  PropertyAccessorElement? lookUpGetter(
-      String getterName, LibraryElement? library) {
-    var element = getGetter(getterName);
-    if (element != null && element.isAccessibleIn(library)) {
-      return element;
-    }
-    return lookUpGetterInSuperclass(getterName, library);
-  }
-
   @override
   PropertyAccessorElement? lookUpGetter2(
     String name,
@@ -756,211 +748,6 @@
     return null;
   }
 
-  @deprecated
-  @override
-  PropertyAccessorElement? lookUpGetterInSuperclass(
-      String getterName, LibraryElement? library) {
-    for (InterfaceType mixin in mixins.reversed) {
-      var element = mixin.getGetter(getterName);
-      if (element != null && element.isAccessibleIn(library)) {
-        return element;
-      }
-    }
-    for (InterfaceType constraint in superclassConstraints) {
-      var element = constraint.getGetter(getterName);
-      if (element != null && element.isAccessibleIn(library)) {
-        return element;
-      }
-    }
-    HashSet<ClassElement> visitedClasses = HashSet<ClassElement>();
-    var supertype = superclass;
-    var supertypeElement = supertype?.element;
-    while (supertype != null &&
-        supertypeElement != null &&
-        !visitedClasses.contains(supertypeElement)) {
-      visitedClasses.add(supertypeElement);
-      var element = supertype.getGetter(getterName);
-      if (element != null && element.isAccessibleIn(library)) {
-        return element;
-      }
-      for (InterfaceType mixin in supertype.mixins.reversed) {
-        element = mixin.getGetter(getterName);
-        if (element != null && element.isAccessibleIn(library)) {
-          return element;
-        }
-      }
-      supertype = supertype.superclass;
-      supertypeElement = supertype?.element;
-    }
-    return null;
-  }
-
-  @deprecated
-  @override
-  PropertyAccessorElement? lookUpInheritedGetter(String name,
-      {LibraryElement? library, bool thisType = true}) {
-    PropertyAccessorElement? result;
-    if (thisType) {
-      result = lookUpGetter(name, library);
-    } else {
-      result = lookUpGetterInSuperclass(name, library);
-    }
-    if (result != null) {
-      return result;
-    }
-    return _lookUpMemberInInterfaces(this, false, library,
-        HashSet<ClassElement>(), (InterfaceType t) => t.getGetter(name));
-  }
-
-  @deprecated
-  @override
-  ExecutableElement? lookUpInheritedGetterOrMethod(String name,
-      {LibraryElement? library}) {
-    var result = lookUpGetter(name, library) ?? lookUpMethod(name, library);
-
-    if (result != null) {
-      return result;
-    }
-    return _lookUpMemberInInterfaces(
-        this,
-        false,
-        library,
-        HashSet<ClassElement>(),
-        (InterfaceType t) => t.getGetter(name) ?? t.getMethod(name));
-  }
-
-  @deprecated
-  ExecutableElement? lookUpInheritedMember(String name, LibraryElement library,
-      {bool concrete = false,
-      bool forSuperInvocation = false,
-      int? startMixinIndex,
-      bool setter = false,
-      bool thisType = false}) {
-    HashSet<ClassElement> visitedClasses = HashSet<ClassElement>();
-
-    /// TODO(scheglov) Remove [includeSupers]. It is used only to work around
-    /// the problem with Flutter code base (using old super-mixins).
-    ExecutableElement? lookUpImpl(InterfaceType? type,
-        {bool acceptAbstract = false,
-        bool includeType = true,
-        bool inMixin = false,
-        int? startMixinIndex}) {
-      if (type == null || !visitedClasses.add(type.element)) {
-        return null;
-      }
-
-      if (includeType) {
-        ExecutableElement? result;
-        if (setter) {
-          result = type.getSetter(name);
-        } else {
-          result = type.getMethod(name);
-          result ??= type.getGetter(name);
-        }
-        if (result != null && result.isAccessibleIn(library)) {
-          if (!concrete || acceptAbstract || !result.isAbstract) {
-            return result;
-          }
-        }
-      }
-
-      if (!inMixin || acceptAbstract) {
-        var mixins = type.mixins;
-        startMixinIndex ??= mixins.length;
-        for (var i = startMixinIndex - 1; i >= 0; i--) {
-          var result = lookUpImpl(
-            mixins[i],
-            acceptAbstract: acceptAbstract,
-            inMixin: true,
-          );
-          if (result != null) {
-            return result;
-          }
-        }
-      }
-
-      // We were not able to find the concrete dispatch target.
-      // It is OK to look into interfaces, we need just some resolution now.
-      if (!concrete) {
-        for (InterfaceType mixin in type.interfaces) {
-          var result = lookUpImpl(mixin, acceptAbstract: acceptAbstract);
-          if (result != null) {
-            return result;
-          }
-        }
-      }
-
-      if (!inMixin || acceptAbstract) {
-        return lookUpImpl(type.superclass,
-            acceptAbstract: acceptAbstract, inMixin: inMixin);
-      }
-
-      return null;
-    }
-
-    if (element.isMixin) {
-      // TODO(scheglov) We should choose the most specific signature.
-      // Not just the first signature.
-      for (InterfaceType constraint in superclassConstraints) {
-        var result = lookUpImpl(constraint, acceptAbstract: true);
-        if (result != null) {
-          return result;
-        }
-      }
-      return null;
-    } else {
-      return lookUpImpl(
-        this,
-        includeType: thisType,
-        startMixinIndex: startMixinIndex,
-      );
-    }
-  }
-
-  @deprecated
-  @override
-  MethodElement? lookUpInheritedMethod(String name,
-      {LibraryElement? library, bool thisType = true}) {
-    MethodElement? result;
-    if (thisType) {
-      result = lookUpMethod(name, library);
-    } else {
-      result = lookUpMethodInSuperclass(name, library);
-    }
-    if (result != null) {
-      return result;
-    }
-    return _lookUpMemberInInterfaces(this, false, library,
-        HashSet<ClassElement>(), (InterfaceType t) => t.getMethod(name));
-  }
-
-  @deprecated
-  @override
-  PropertyAccessorElement? lookUpInheritedSetter(String name,
-      {LibraryElement? library, bool thisType = true}) {
-    PropertyAccessorElement? result;
-    if (thisType) {
-      result = lookUpSetter(name, library);
-    } else {
-      result = lookUpSetterInSuperclass(name, library);
-    }
-    if (result != null) {
-      return result;
-    }
-    return _lookUpMemberInInterfaces(this, false, library,
-        HashSet<ClassElement>(), (t) => t.getSetter(name));
-  }
-
-  @deprecated
-  @override
-  MethodElement? lookUpMethod(String methodName, LibraryElement? library) {
-    var element = getMethod(methodName);
-    if (element != null && element.isAccessibleIn(library)) {
-      return element;
-    }
-    return lookUpMethodInSuperclass(methodName, library);
-  }
-
   @override
   MethodElement? lookUpMethod2(
     String name,
@@ -1000,56 +787,6 @@
     return null;
   }
 
-  @deprecated
-  @override
-  MethodElement? lookUpMethodInSuperclass(
-      String methodName, LibraryElement? library) {
-    for (InterfaceType mixin in mixins.reversed) {
-      var element = mixin.getMethod(methodName);
-      if (element != null && element.isAccessibleIn(library)) {
-        return element;
-      }
-    }
-    for (InterfaceType constraint in superclassConstraints) {
-      var element = constraint.getMethod(methodName);
-      if (element != null && element.isAccessibleIn(library)) {
-        return element;
-      }
-    }
-    HashSet<ClassElement> visitedClasses = HashSet<ClassElement>();
-    var supertype = superclass;
-    var supertypeElement = supertype?.element;
-    while (supertype != null &&
-        supertypeElement != null &&
-        !visitedClasses.contains(supertypeElement)) {
-      visitedClasses.add(supertypeElement);
-      var element = supertype.getMethod(methodName);
-      if (element != null && element.isAccessibleIn(library)) {
-        return element;
-      }
-      for (InterfaceType mixin in supertype.mixins.reversed) {
-        element = mixin.getMethod(methodName);
-        if (element != null && element.isAccessibleIn(library)) {
-          return element;
-        }
-      }
-      supertype = supertype.superclass;
-      supertypeElement = supertype?.element;
-    }
-    return null;
-  }
-
-  @deprecated
-  @override
-  PropertyAccessorElement? lookUpSetter(
-      String setterName, LibraryElement? library) {
-    var element = getSetter(setterName);
-    if (element != null && element.isAccessibleIn(library)) {
-      return element;
-    }
-    return lookUpSetterInSuperclass(setterName, library);
-  }
-
   @override
   PropertyAccessorElement? lookUpSetter2(
     String name,
@@ -1089,45 +826,6 @@
     return null;
   }
 
-  @deprecated
-  @override
-  PropertyAccessorElement? lookUpSetterInSuperclass(
-      String setterName, LibraryElement? library) {
-    for (InterfaceType mixin in mixins.reversed) {
-      var element = mixin.getSetter(setterName);
-      if (element != null && element.isAccessibleIn(library)) {
-        return element;
-      }
-    }
-    for (InterfaceType constraint in superclassConstraints) {
-      var element = constraint.getSetter(setterName);
-      if (element != null && element.isAccessibleIn(library)) {
-        return element;
-      }
-    }
-    HashSet<ClassElement> visitedClasses = HashSet<ClassElement>();
-    var supertype = superclass;
-    var supertypeElement = supertype?.element;
-    while (supertype != null &&
-        supertypeElement != null &&
-        !visitedClasses.contains(supertypeElement)) {
-      visitedClasses.add(supertypeElement);
-      var element = supertype.getSetter(setterName);
-      if (element != null && element.isAccessibleIn(library)) {
-        return element;
-      }
-      for (InterfaceType mixin in supertype.mixins.reversed) {
-        element = mixin.getSetter(setterName);
-        if (element != null && element.isAccessibleIn(library)) {
-          return element;
-        }
-      }
-      supertype = supertype.superclass;
-      supertypeElement = supertype?.element;
-    }
-    return null;
-  }
-
   @override
   bool referencesAny(Set<TypeParameterElement> parameters) {
     return typeArguments.any((argument) {
@@ -1160,140 +858,6 @@
     }
     return result;
   }
-
-  /// Returns a "smart" version of the "least upper bound" of the given types.
-  ///
-  /// If these types have the same element and differ only in terms of the type
-  /// arguments, attempts to find a compatible set of type arguments.
-  ///
-  /// Otherwise, calls [DartType.getLeastUpperBound].
-  @Deprecated('Use TypeSystem.leastUpperBound instead')
-  static InterfaceType getSmartLeastUpperBound(
-      InterfaceType first, InterfaceType second) {
-    // TODO(paulberry): this needs to be deprecated and replaced with a method
-    // in [TypeSystem], since it relies on the deprecated functionality of
-    // [DartType.getLeastUpperBound].
-    if (first.element == second.element) {
-      return _leastUpperBound(first, second);
-    }
-    var typeSystem = first.element.library.typeSystem as TypeSystemImpl;
-    return typeSystem.getLeastUpperBound(first, second) as InterfaceType;
-  }
-
-  /// Return the "least upper bound" of the given types under the assumption
-  /// that the types have the same element and differ only in terms of the type
-  /// arguments.
-  ///
-  /// The resulting type is composed by comparing the corresponding type
-  /// arguments, keeping those that are the same, and using 'dynamic' for those
-  /// that are different.
-  static InterfaceType _leastUpperBound(
-      InterfaceType firstType, InterfaceType secondType) {
-    ClassElement firstElement = firstType.element;
-    ClassElement secondElement = secondType.element;
-    if (firstElement != secondElement) {
-      throw ArgumentError('The same elements expected, but '
-          '$firstElement and $secondElement are given.');
-    }
-    if (firstType == secondType) {
-      return firstType;
-    }
-    List<DartType> firstArguments = firstType.typeArguments;
-    List<DartType> secondArguments = secondType.typeArguments;
-    int argumentCount = firstArguments.length;
-    if (argumentCount == 0) {
-      return firstType;
-    }
-    var lubArguments = List<DartType>.filled(
-      argumentCount,
-      DynamicTypeImpl.instance,
-    );
-    for (int i = 0; i < argumentCount; i++) {
-      //
-      // Ideally we would take the least upper bound of the two argument types,
-      // but this can cause an infinite recursion (such as when finding the
-      // least upper bound of String and num).
-      //
-      if (firstArguments[i] == secondArguments[i]) {
-        lubArguments[i] = firstArguments[i];
-      }
-    }
-
-    NullabilitySuffix computeNullability() {
-      NullabilitySuffix first = firstType.nullabilitySuffix;
-      NullabilitySuffix second = secondType.nullabilitySuffix;
-      if (first == NullabilitySuffix.question ||
-          second == NullabilitySuffix.question) {
-        return NullabilitySuffix.question;
-      } else if (first == NullabilitySuffix.star ||
-          second == NullabilitySuffix.star) {
-        return NullabilitySuffix.star;
-      }
-      return NullabilitySuffix.none;
-    }
-
-    return InterfaceTypeImpl(
-      element: firstElement,
-      typeArguments: lubArguments,
-      nullabilitySuffix: computeNullability(),
-    );
-  }
-
-  /// Look up the getter with the given name in the interfaces implemented by
-  /// the given [targetType], either directly or indirectly. Return the element
-  /// representing the getter that was found, or `null` if there is no getter
-  /// with the given name. The flag [includeTargetType] should be `true` if the
-  /// search should include the target type. The [visitedInterfaces] is a set
-  /// containing all of the interfaces that have been examined, used to prevent
-  /// infinite recursion and to optimize the search.
-  static T? _lookUpMemberInInterfaces<T extends ExecutableElement>(
-      InterfaceType targetType,
-      bool includeTargetType,
-      LibraryElement? library,
-      HashSet<ClassElement> visitedInterfaces,
-      T? Function(InterfaceType type) getMember) {
-    // TODO(brianwilkerson) This isn't correct. Section 8.1.1 of the
-    // specification (titled "Inheritance and Overriding" under "Interfaces")
-    // describes a much more complex scheme for finding the inherited member.
-    // We need to follow that scheme. The code below should cover the 80% case.
-    ClassElement targetClass = targetType.element;
-    if (!visitedInterfaces.add(targetClass)) {
-      return null;
-    }
-    if (includeTargetType) {
-      var member = getMember(targetType);
-      if (member != null && member.isAccessibleIn(library)) {
-        return member;
-      }
-    }
-    for (InterfaceType interfaceType in targetType.interfaces) {
-      var member = _lookUpMemberInInterfaces(
-          interfaceType, true, library, visitedInterfaces, getMember);
-      if (member != null) {
-        return member;
-      }
-    }
-    for (InterfaceType constraint in targetType.superclassConstraints) {
-      var member = _lookUpMemberInInterfaces(
-          constraint, true, library, visitedInterfaces, getMember);
-      if (member != null) {
-        return member;
-      }
-    }
-    for (InterfaceType mixinType in targetType.mixins.reversed) {
-      var member = _lookUpMemberInInterfaces(
-          mixinType, true, library, visitedInterfaces, getMember);
-      if (member != null) {
-        return member;
-      }
-    }
-    var superclass = targetType.superclass;
-    if (superclass == null) {
-      return null;
-    }
-    return _lookUpMemberInInterfaces(
-        superclass, true, library, visitedInterfaces, getMember);
-  }
 }
 
 /// The type `Never` represents the uninhabited bottom type.
@@ -1393,18 +957,6 @@
   /// Initialize a newly created type to be declared by the given [element].
   TypeImpl(this._element, {this.alias});
 
-  @Deprecated('Use alias instead')
-  @override
-  List<DartType>? get aliasArguments {
-    return alias?.typeArguments;
-  }
-
-  @Deprecated('Use alias instead')
-  @override
-  TypeAliasElement? get aliasElement {
-    return alias?.element;
-  }
-
   @deprecated
   @override
   String get displayName {
@@ -1427,6 +979,9 @@
   bool get isDartAsyncFutureOr => false;
 
   @override
+  bool get isDartAsyncStream => false;
+
+  @override
   bool get isDartCoreBool => false;
 
   @override
diff --git a/pkg/analyzer/lib/src/dart/element/type_provider.dart b/pkg/analyzer/lib/src/dart/element/type_provider.dart
index 948b8c448..15242b5 100644
--- a/pkg/analyzer/lib/src/dart/element/type_provider.dart
+++ b/pkg/analyzer/lib/src/dart/element/type_provider.dart
@@ -149,8 +149,6 @@
 
   InterfaceType? _nullStar;
 
-  Set<ClassElement>? _nonSubtypableClasses;
-
   /// Initialize a newly created type provider to provide the types defined in
   /// the given [coreLibrary] and [asyncLibrary].
   TypeProviderImpl({
@@ -353,18 +351,6 @@
       ? NeverTypeImpl.instance
       : NeverTypeImpl.instanceLegacy;
 
-  @Deprecated('Use isNonSubtypableClass instead')
-  @override
-  Set<ClassElement> get nonSubtypableClasses => _nonSubtypableClasses ??= {
-        boolElement,
-        doubleElement,
-        futureOrElement,
-        intElement,
-        nullElement,
-        numElement,
-        stringElement,
-      };
-
   @override
   ClassElement get nullElement {
     return _nullElement ??= _getClassElement(_coreLibrary, 'Null');
@@ -473,12 +459,6 @@
     );
   }
 
-  @Deprecated('Use futureOrType instead')
-  @override
-  InterfaceType futureOrType2(DartType valueType) {
-    return futureOrType(valueType);
-  }
-
   @override
   InterfaceType futureType(DartType valueType) {
     return futureElement.instantiate(
@@ -487,12 +467,6 @@
     );
   }
 
-  @Deprecated('Use futureType instead')
-  @override
-  InterfaceType futureType2(DartType valueType) {
-    return futureType(valueType);
-  }
-
   @override
   bool isNonSubtypableClass(ClassElement element) {
     var name = element.name;
@@ -512,12 +486,6 @@
     );
   }
 
-  @Deprecated('Use iterableType instead')
-  @override
-  InterfaceType iterableType2(DartType elementType) {
-    return iterableType(elementType);
-  }
-
   @override
   InterfaceType listType(DartType elementType) {
     return listElement.instantiate(
@@ -526,12 +494,6 @@
     );
   }
 
-  @Deprecated('Use listType instead')
-  @override
-  InterfaceType listType2(DartType elementType) {
-    return listType(elementType);
-  }
-
   @override
   InterfaceType mapType(DartType keyType, DartType valueType) {
     return mapElement.instantiate(
@@ -540,12 +502,6 @@
     );
   }
 
-  @Deprecated('Use mapType instead')
-  @override
-  InterfaceType mapType2(DartType keyType, DartType valueType) {
-    return mapType(keyType, valueType);
-  }
-
   @override
   InterfaceType setType(DartType elementType) {
     return setElement.instantiate(
@@ -554,12 +510,6 @@
     );
   }
 
-  @Deprecated('Use setType instead')
-  @override
-  InterfaceType setType2(DartType elementType) {
-    return setType(elementType);
-  }
-
   @override
   InterfaceType streamType(DartType elementType) {
     return streamElement.instantiate(
@@ -568,12 +518,6 @@
     );
   }
 
-  @Deprecated('Use streamType instead')
-  @override
-  InterfaceType streamType2(DartType elementType) {
-    return streamType(elementType);
-  }
-
   /// Return the class with the given [name] from the given [library], or
   /// throw a [StateError] if there is no class with the given name.
   ClassElement _getClassElement(LibraryElement library, String name) {
diff --git a/pkg/analyzer/lib/src/dart/error/ffi_code.g.dart b/pkg/analyzer/lib/src/dart/error/ffi_code.g.dart
index e794a9b..620289c 100644
--- a/pkg/analyzer/lib/src/dart/error/ffi_code.g.dart
+++ b/pkg/analyzer/lib/src/dart/error/ffi_code.g.dart
@@ -18,9 +18,23 @@
   /**
    * No parameters.
    */
+  static const FfiCode ABI_SPECIFIC_INTEGER_INVALID = FfiCode(
+    'ABI_SPECIFIC_INTEGER_INVALID',
+    "Classes extending 'AbiSpecificInteger' must have exactly one const "
+        "constructor, no other members, and no type arguments.",
+    correctionMessage:
+        "Try removing all type arguments, removing all members, and adding one "
+        "const constructor.",
+  );
+
+  /**
+   * No parameters.
+   */
   static const FfiCode ABI_SPECIFIC_INTEGER_MAPPING_EXTRA = FfiCode(
     'ABI_SPECIFIC_INTEGER_MAPPING_EXTRA',
-    "Classes extending 'AbiSpecificInteger' must have exactly one 'AbiSpecificIntegerMapping' annotation specifying the mapping from ABI to a 'NativeType' integer with a fixed size.",
+    "Classes extending 'AbiSpecificInteger' must have exactly one "
+        "'AbiSpecificIntegerMapping' annotation specifying the mapping from "
+        "ABI to a 'NativeType' integer with a fixed size.",
     correctionMessage: "Try removing the extra annotation.",
   );
 
@@ -29,7 +43,9 @@
    */
   static const FfiCode ABI_SPECIFIC_INTEGER_MAPPING_MISSING = FfiCode(
     'ABI_SPECIFIC_INTEGER_MAPPING_MISSING',
-    "Classes extending 'AbiSpecificInteger' must have exactly one 'AbiSpecificIntegerMapping' annotation specifying the mapping from ABI to a 'NativeType' integer with a fixed size.",
+    "Classes extending 'AbiSpecificInteger' must have exactly one "
+        "'AbiSpecificIntegerMapping' annotation specifying the mapping from "
+        "ABI to a 'NativeType' integer with a fixed size.",
     correctionMessage: "Try adding an annotation.",
   );
 
@@ -38,9 +54,11 @@
    */
   static const FfiCode ABI_SPECIFIC_INTEGER_MAPPING_UNSUPPORTED = FfiCode(
     'ABI_SPECIFIC_INTEGER_MAPPING_UNSUPPORTED',
-    "Only mappings to 'Int8', 'Int16', 'Int32', 'Int64', 'Uint8', 'Uint16', 'UInt32', and 'Uint64' are supported.",
+    "Only mappings to 'Int8', 'Int16', 'Int32', 'Int64', 'Uint8', 'Uint16', "
+        "'UInt32', and 'Uint64' are supported.",
     correctionMessage:
-        "Try changing the value to 'Int8', 'Int16', 'Int32', 'Int64', 'Uint8', 'Uint16', 'UInt32', or 'Uint64'.",
+        "Try changing the value to 'Int8', 'Int16', 'Int32', 'Int64', 'Uint8', "
+        "'Uint16', 'UInt32', or 'Uint64'.",
   );
 
   /**
@@ -48,7 +66,8 @@
    */
   static const FfiCode ANNOTATION_ON_POINTER_FIELD = FfiCode(
     'ANNOTATION_ON_POINTER_FIELD',
-    "Fields in a struct class whose type is 'Pointer' should not have any annotations.",
+    "Fields in a struct class whose type is 'Pointer' should not have any "
+        "annotations.",
     correctionMessage: "Try removing the annotation.",
   );
 
@@ -67,7 +86,8 @@
    */
   static const FfiCode CREATION_OF_STRUCT_OR_UNION = FfiCode(
     'CREATION_OF_STRUCT_OR_UNION',
-    "Subclasses of 'Struct' and 'Union' are backed by native memory, and can't be instantiated by a generative constructor.",
+    "Subclasses of 'Struct' and 'Union' are backed by native memory, and can't "
+        "be instantiated by a generative constructor.",
     correctionMessage:
         "Try allocating it via allocation, or load from a 'Pointer'.",
   );
@@ -89,7 +109,8 @@
    */
   static const FfiCode EXTRA_ANNOTATION_ON_STRUCT_FIELD = FfiCode(
     'EXTRA_ANNOTATION_ON_STRUCT_FIELD',
-    "Fields in a struct class must have exactly one annotation indicating the native type.",
+    "Fields in a struct class must have exactly one annotation indicating the "
+        "native type.",
     correctionMessage: "Try removing the extra annotation.",
   );
 
@@ -129,7 +150,8 @@
    */
   static const FfiCode FFI_NATIVE_UNEXPECTED_NUMBER_OF_PARAMETERS = FfiCode(
     'FFI_NATIVE_UNEXPECTED_NUMBER_OF_PARAMETERS',
-    "Unexpected number of FfiNative annotation parameters. Expected {0} but has {1}.",
+    "Unexpected number of FfiNative annotation parameters. Expected {0} but "
+        "has {1}.",
     correctionMessage: "Make sure parameters match the function annotated.",
   );
 
@@ -141,9 +163,12 @@
   static const FfiCode
       FFI_NATIVE_UNEXPECTED_NUMBER_OF_PARAMETERS_WITH_RECEIVER = FfiCode(
     'FFI_NATIVE_UNEXPECTED_NUMBER_OF_PARAMETERS_WITH_RECEIVER',
-    "Unexpected number of FfiNative annotation parameters. Expected {0} but has {1}. FfiNative instance method annotation must have receiver as first argument.",
+    "Unexpected number of FfiNative annotation parameters. Expected {0} but "
+        "has {1}. FfiNative instance method annotation must have receiver as "
+        "first argument.",
     correctionMessage:
-        "Make sure parameters match the function annotated, including an extra first parameter for the receiver.",
+        "Make sure parameters match the function annotated, including an extra "
+        "first parameter for the receiver.",
   );
 
   /**
@@ -151,7 +176,8 @@
    */
   static const FfiCode FIELD_INITIALIZER_IN_STRUCT = FfiCode(
     'FIELD_INITIALIZER_IN_STRUCT',
-    "Constructors in subclasses of 'Struct' and 'Union' can't have field initializers.",
+    "Constructors in subclasses of 'Struct' and 'Union' can't have field "
+        "initializers.",
     correctionMessage:
         "Try removing the field initializer and marking the field as external.",
   );
@@ -190,7 +216,9 @@
    */
   static const FfiCode INVALID_EXCEPTION_VALUE = FfiCode(
     'INVALID_EXCEPTION_VALUE',
-    "The method 'Pointer.fromFunction' must not have an exceptional return value (the second argument) when the return type of the function is either 'void', 'Handle' or 'Pointer'.",
+    "The method 'Pointer.fromFunction' must not have an exceptional return "
+        "value (the second argument) when the return type of the function is "
+        "either 'void', 'Handle' or 'Pointer'.",
     correctionMessage: "Try removing the exceptional return value.",
   );
 
@@ -200,9 +228,12 @@
    */
   static const FfiCode INVALID_FIELD_TYPE_IN_STRUCT = FfiCode(
     'INVALID_FIELD_TYPE_IN_STRUCT',
-    "Fields in struct classes can't have the type '{0}'. They can only be declared as 'int', 'double', 'Array', 'Pointer', or subtype of 'Struct' or 'Union'.",
+    "Fields in struct classes can't have the type '{0}'. They can only be "
+        "declared as 'int', 'double', 'Array', 'Pointer', or subtype of "
+        "'Struct' or 'Union'.",
     correctionMessage:
-        "Try using 'int', 'double', 'Array', 'Pointer', or subtype of 'Struct' or 'Union'.",
+        "Try using 'int', 'double', 'Array', 'Pointer', or subtype of 'Struct' "
+        "or 'Union'.",
   );
 
   /**
@@ -230,7 +261,8 @@
     'MISMATCHED_ANNOTATION_ON_STRUCT_FIELD',
     "The annotation does not match the declared type of the field.",
     correctionMessage:
-        "Try using a different annotation or changing the declared type to match.",
+        "Try using a different annotation or changing the declared type to "
+        "match.",
   );
 
   /**
@@ -238,7 +270,8 @@
    */
   static const FfiCode MISSING_ANNOTATION_ON_STRUCT_FIELD = FfiCode(
     'MISSING_ANNOTATION_ON_STRUCT_FIELD',
-    "Fields in a struct class must either have the type 'Pointer' or an annotation indicating the native type.",
+    "Fields in a struct class must either have the type 'Pointer' or an "
+        "annotation indicating the native type.",
     correctionMessage: "Try adding an annotation.",
   );
 
@@ -247,7 +280,9 @@
    */
   static const FfiCode MISSING_EXCEPTION_VALUE = FfiCode(
     'MISSING_EXCEPTION_VALUE',
-    "The method 'Pointer.fromFunction' must have an exceptional return value (the second argument) when the return type of the function is neither 'void', 'Handle' or 'Pointer'.",
+    "The method 'Pointer.fromFunction' must have an exceptional return value "
+        "(the second argument) when the return type of the function is neither "
+        "'void', 'Handle' or 'Pointer'.",
     correctionMessage: "Try adding an exceptional return value.",
   );
 
@@ -257,7 +292,8 @@
    */
   static const FfiCode MISSING_FIELD_TYPE_IN_STRUCT = FfiCode(
     'MISSING_FIELD_TYPE_IN_STRUCT',
-    "Fields in struct classes must have an explicitly declared type of 'int', 'double' or 'Pointer'.",
+    "Fields in struct classes must have an explicitly declared type of 'int', "
+        "'double' or 'Pointer'.",
     correctionMessage: "Try using 'int', 'double' or 'Pointer'.",
   );
 
@@ -277,7 +313,8 @@
    */
   static const FfiCode MUST_BE_A_NATIVE_FUNCTION_TYPE = FfiCode(
     'MUST_BE_A_NATIVE_FUNCTION_TYPE',
-    "The type '{0}' given to '{1}' must be a valid 'dart:ffi' native function type.",
+    "The type '{0}' given to '{1}' must be a valid 'dart:ffi' native function "
+        "type.",
     correctionMessage:
         "Try changing the type to only use members for 'dart:ffi'.",
   );
@@ -300,7 +337,8 @@
    */
   static const FfiCode NON_CONSTANT_TYPE_ARGUMENT = FfiCode(
     'NON_CONSTANT_TYPE_ARGUMENT',
-    "The type arguments to '{0}' must be compile time constants but type parameters are not constants.",
+    "The type arguments to '{0}' must be compile time constants but type "
+        "parameters are not constants.",
     correctionMessage: "Try changing the type argument to be a constant type.",
   );
 
@@ -310,9 +348,11 @@
    */
   static const FfiCode NON_NATIVE_FUNCTION_TYPE_ARGUMENT_TO_POINTER = FfiCode(
     'NON_NATIVE_FUNCTION_TYPE_ARGUMENT_TO_POINTER',
-    "The type argument for the pointer '{0}' must be a valid 'NativeFunction' in order to use 'asFunction'.",
+    "The type argument for the pointer '{0}' must be a valid 'NativeFunction' "
+        "in order to use 'asFunction'.",
     correctionMessage:
-        "Try changing the function argument in 'NativeFunction' to only use NativeTypes.",
+        "Try changing the function argument in 'NativeFunction' to only use "
+        "NativeTypes.",
   );
 
   /**
@@ -330,9 +370,12 @@
    */
   static const FfiCode NON_SIZED_TYPE_ARGUMENT = FfiCode(
     'NON_SIZED_TYPE_ARGUMENT',
-    "Type arguments to '{0}' can't have the type '{1}'. They can only be declared as native integer, 'Float', 'Double', 'Pointer', or subtype of 'Struct', 'Union', or 'AbiSpecificInteger'.",
+    "Type arguments to '{0}' can't have the type '{1}'. They can only be "
+        "declared as native integer, 'Float', 'Double', 'Pointer', or subtype "
+        "of 'Struct', 'Union', or 'AbiSpecificInteger'.",
     correctionMessage:
-        "Try using a native integer, 'Float', 'Double', 'Pointer', or subtype of 'Struct', 'Union', or 'AbiSpecificInteger'.",
+        "Try using a native integer, 'Float', 'Double', 'Pointer', or subtype "
+        "of 'Struct', 'Union', or 'AbiSpecificInteger'.",
   );
 
   /**
@@ -361,9 +404,11 @@
    */
   static const FfiCode PACKED_NESTING_NON_PACKED = FfiCode(
     'PACKED_NESTING_NON_PACKED',
-    "Nesting the non-packed or less tightly packed struct '{0}' in a packed struct '{1}' is not supported.",
+    "Nesting the non-packed or less tightly packed struct '{0}' in a packed "
+        "struct '{1}' is not supported.",
     correctionMessage:
-        "Try packing the nested struct or packing the nested struct more tightly.",
+        "Try packing the nested struct or packing the nested struct more "
+        "tightly.",
   );
 
   /**
@@ -418,8 +463,10 @@
    */
   static const FfiCode SUBTYPE_OF_STRUCT_CLASS_IN_EXTENDS = FfiCode(
     'SUBTYPE_OF_STRUCT_CLASS',
-    "The class '{0}' can't extend '{1}' because '{1}' is a subtype of 'Struct' or 'Union'.",
-    correctionMessage: "Try extending 'Struct' or 'Union' directly.",
+    "The class '{0}' can't extend '{1}' because '{1}' is a subtype of "
+        "'Struct', 'Union', or 'AbiSpecificInteger'.",
+    correctionMessage:
+        "Try extending 'Struct', 'Union', or 'AbiSpecificInteger' directly.",
     uniqueName: 'SUBTYPE_OF_STRUCT_CLASS_IN_EXTENDS',
   );
 
@@ -430,8 +477,10 @@
    */
   static const FfiCode SUBTYPE_OF_STRUCT_CLASS_IN_IMPLEMENTS = FfiCode(
     'SUBTYPE_OF_STRUCT_CLASS',
-    "The class '{0}' can't implement '{1}' because '{1}' is a subtype of 'Struct' or 'Union'.",
-    correctionMessage: "Try extending 'Struct' or 'Union' directly.",
+    "The class '{0}' can't implement '{1}' because '{1}' is a subtype of "
+        "'Struct', 'Union', or 'AbiSpecificInteger'.",
+    correctionMessage:
+        "Try extending 'Struct', 'Union', or 'AbiSpecificInteger' directly.",
     uniqueName: 'SUBTYPE_OF_STRUCT_CLASS_IN_IMPLEMENTS',
   );
 
@@ -442,8 +491,10 @@
    */
   static const FfiCode SUBTYPE_OF_STRUCT_CLASS_IN_WITH = FfiCode(
     'SUBTYPE_OF_STRUCT_CLASS',
-    "The class '{0}' can't mix in '{1}' because '{1}' is a subtype of 'Struct' or 'Union'.",
-    correctionMessage: "Try extending 'Struct' or 'Union' directly.",
+    "The class '{0}' can't mix in '{1}' because '{1}' is a subtype of "
+        "'Struct', 'Union', or 'AbiSpecificInteger'.",
+    correctionMessage:
+        "Try extending 'Struct', 'Union', or 'AbiSpecificInteger' directly.",
     uniqueName: 'SUBTYPE_OF_STRUCT_CLASS_IN_WITH',
   );
 
diff --git a/pkg/analyzer/lib/src/dart/error/hint_codes.g.dart b/pkg/analyzer/lib/src/dart/error/hint_codes.g.dart
index fae4e5e..8c78fc5 100644
--- a/pkg/analyzer/lib/src/dart/error/hint_codes.g.dart
+++ b/pkg/analyzer/lib/src/dart/error/hint_codes.g.dart
@@ -75,7 +75,8 @@
   static const HintCode ARGUMENT_TYPE_NOT_ASSIGNABLE_TO_ERROR_HANDLER =
       HintCode(
     'ARGUMENT_TYPE_NOT_ASSIGNABLE_TO_ERROR_HANDLER',
-    "The argument type '{0}' can't be assigned to the parameter type '{1} Function(Object)' or '{1} Function(Object, StackTrace)'.",
+    "The argument type '{0}' can't be assigned to the parameter type '{1} "
+        "Function(Object)' or '{1} Function(Object, StackTrace)'.",
     hasPublishedDocs: true,
   );
 
@@ -84,11 +85,25 @@
    */
   static const HintCode ASSIGNMENT_OF_DO_NOT_STORE = HintCode(
     'ASSIGNMENT_OF_DO_NOT_STORE',
-    "'{0}' is marked 'doNotStore' and shouldn't be assigned to a field or top-level variable.",
+    "'{0}' is marked 'doNotStore' and shouldn't be assigned to a field or "
+        "top-level variable.",
     correctionMessage: "Try removing the assignment.",
   );
 
   /**
+   * Parameters:
+   * 0: the name of the declared return type
+   */
+  static const HintCode BODY_MIGHT_COMPLETE_NORMALLY_NULLABLE = HintCode(
+    'BODY_MIGHT_COMPLETE_NORMALLY_NULLABLE',
+    "This function has a nullable return type of '{0}', but ends without "
+        "returning a value.",
+    correctionMessage:
+        "Try adding a return statement, or if no value is ever returned, try "
+        "changing the return type to 'void'.",
+  );
+
+  /**
    * When the target expression uses '?.' operator, it can be `null`, so all the
    * subsequent invocations should also use '?.' operator.
    */
@@ -155,7 +170,8 @@
     'DEAD_CODE',
     "Dead code.",
     correctionMessage:
-        "Try removing the code, or fixing the code before it so that it can be reached.",
+        "Try removing the code, or fixing the code before it so that it can be "
+        "reached.",
     hasPublishedDocs: true,
   );
 
@@ -211,9 +227,11 @@
   // ```
   static const HintCode DEAD_CODE_CATCH_FOLLOWING_CATCH = HintCode(
     'DEAD_CODE_CATCH_FOLLOWING_CATCH',
-    "Dead code: Catch clauses after a 'catch (e)' or an 'on Object catch (e)' are never reached.",
+    "Dead code: Catch clauses after a 'catch (e)' or an 'on Object catch (e)' "
+        "are never reached.",
     correctionMessage:
-        "Try reordering the catch clauses so that they can be reached, or removing the unreachable catch clauses.",
+        "Try reordering the catch clauses so that they can be reached, or "
+        "removing the unreachable catch clauses.",
     hasPublishedDocs: true,
   );
 
@@ -273,9 +291,11 @@
   // ```
   static const HintCode DEAD_CODE_ON_CATCH_SUBTYPE = HintCode(
     'DEAD_CODE_ON_CATCH_SUBTYPE',
-    "Dead code: This on-catch block won’t be executed because '{0}' is a subtype of '{1}' and hence will have been caught already.",
+    "Dead code: This on-catch block won’t be executed because '{0}' is a "
+        "subtype of '{1}' and hence will have been caught already.",
     correctionMessage:
-        "Try reordering the catch clauses so that this block can be reached, or removing the unreachable catch clause.",
+        "Try reordering the catch clauses so that this block can be reached, "
+        "or removing the unreachable catch clause.",
     hasPublishedDocs: true,
   );
 
@@ -551,9 +571,11 @@
   // ```
   static const HintCode DUPLICATE_IGNORE = HintCode(
     'DUPLICATE_IGNORE',
-    "The diagnostic '{0}' doesn't need to be ignored here because it's already being ignored.",
+    "The diagnostic '{0}' doesn't need to be ignored here because it's already "
+        "being ignored.",
     correctionMessage:
-        "Try removing the name from the list, or removing the whole comment if this is the only name in the list.",
+        "Try removing the name from the list, or removing the whole comment if "
+        "this is the only name in the list.",
     hasPublishedDocs: true,
   );
 
@@ -750,9 +772,11 @@
   static const HintCode FILE_IMPORT_INSIDE_LIB_REFERENCES_FILE_OUTSIDE =
       HintCode(
     'FILE_IMPORT_INSIDE_LIB_REFERENCES_FILE_OUTSIDE',
-    "A file in the 'lib' directory shouldn't import a file outside the 'lib' directory.",
+    "A file in the 'lib' directory shouldn't import a file outside the 'lib' "
+        "directory.",
     correctionMessage:
-        "Try removing the import, or moving the imported file inside the 'lib' directory.",
+        "Try removing the import, or moving the imported file inside the 'lib' "
+        "directory.",
   );
 
   /**
@@ -765,7 +789,8 @@
   static const HintCode FILE_IMPORT_OUTSIDE_LIB_REFERENCES_FILE_INSIDE =
       HintCode(
     'FILE_IMPORT_OUTSIDE_LIB_REFERENCES_FILE_INSIDE',
-    "A file outside the 'lib' directory shouldn't reference a file inside the 'lib' directory using a relative path.",
+    "A file outside the 'lib' directory shouldn't reference a file inside the "
+        "'lib' directory using a relative path.",
     correctionMessage: "Try using a package: URI instead.",
   );
 
@@ -844,9 +869,11 @@
   // with the `@optionalTypeArgs` annotation (from `package:meta`):
   static const HintCode IMPORT_DEFERRED_LIBRARY_WITH_LOAD_FUNCTION = HintCode(
     'IMPORT_DEFERRED_LIBRARY_WITH_LOAD_FUNCTION',
-    "The imported library defines a top-level function named 'loadLibrary' that is hidden by deferring this library.",
+    "The imported library defines a top-level function named 'loadLibrary' "
+        "that is hidden by deferring this library.",
     correctionMessage:
-        "Try changing the import to not be deferred, or rename the function in the imported library.",
+        "Try changing the import to not be deferred, or rename the function in "
+        "the imported library.",
     hasPublishedDocs: true,
   );
 
@@ -855,7 +882,8 @@
    */
   static const HintCode IMPORT_OF_LEGACY_LIBRARY_INTO_NULL_SAFE = HintCode(
     'IMPORT_OF_LEGACY_LIBRARY_INTO_NULL_SAFE',
-    "The library '{0}' is legacy, and should not be imported into a null safe library.",
+    "The library '{0}' is legacy, and should not be imported into a null safe "
+        "library.",
     correctionMessage: "Try migrating the imported library.",
   );
 
@@ -898,7 +926,8 @@
    */
   static const HintCode INFERENCE_FAILURE_ON_GENERIC_INVOCATION = HintCode(
     'INFERENCE_FAILURE_ON_GENERIC_INVOCATION',
-    "The type argument(s) of the generic function type '{0}' can't be inferred.",
+    "The type argument(s) of the generic function type '{0}' can't be "
+        "inferred.",
     correctionMessage: "Use explicit type argument(s) for '{0}'.",
   );
 
@@ -966,7 +995,8 @@
   static const HintCode INVALID_EXPORT_OF_INTERNAL_ELEMENT_INDIRECTLY =
       HintCode(
     'INVALID_EXPORT_OF_INTERNAL_ELEMENT_INDIRECTLY',
-    "The member '{0}' can't be exported as a part of a package's public API, but is indirectly exported as part of the signature of '{1}'.",
+    "The member '{0}' can't be exported as a part of a package's public API, "
+        "but is indirectly exported as part of the signature of '{1}'.",
     correctionMessage: "Try using a hide clause to hide '{0}'.",
   );
 
@@ -1016,7 +1046,8 @@
    */
   static const HintCode INVALID_INTERNAL_ANNOTATION = HintCode(
     'INVALID_INTERNAL_ANNOTATION',
-    "Only public elements in a package's private API can be annotated as being internal.",
+    "Only public elements in a package's private API can be annotated as being "
+        "internal.",
   );
 
   /**
@@ -1035,7 +1066,8 @@
     'INVALID_LANGUAGE_VERSION_OVERRIDE',
     "The Dart language version override number must begin with '@dart'",
     correctionMessage:
-        "Specify a Dart language version override with a comment like '// @dart = 2.0'.",
+        "Specify a Dart language version override with a comment like '// "
+        "@dart = 2.0'.",
     uniqueName: 'INVALID_LANGUAGE_VERSION_OVERRIDE_AT_SIGN',
   );
 
@@ -1053,22 +1085,26 @@
    */
   static const HintCode INVALID_LANGUAGE_VERSION_OVERRIDE_EQUALS = HintCode(
     'INVALID_LANGUAGE_VERSION_OVERRIDE',
-    "The Dart language version override comment must be specified with an '=' character",
+    "The Dart language version override comment must be specified with an '=' "
+        "character",
     correctionMessage:
-        "Specify a Dart language version override with a comment like '// @dart = 2.0'.",
+        "Specify a Dart language version override with a comment like '// "
+        "@dart = 2.0'.",
     uniqueName: 'INVALID_LANGUAGE_VERSION_OVERRIDE_EQUALS',
   );
 
   static const HintCode INVALID_LANGUAGE_VERSION_OVERRIDE_GREATER = HintCode(
     'INVALID_LANGUAGE_VERSION_OVERRIDE',
-    "The language version override can't specify a version greater than the latest known language version: {0}.{1}",
+    "The language version override can't specify a version greater than the "
+        "latest known language version: {0}.{1}",
     correctionMessage: "Try removing the language version override.",
     uniqueName: 'INVALID_LANGUAGE_VERSION_OVERRIDE_GREATER',
   );
 
   static const HintCode INVALID_LANGUAGE_VERSION_OVERRIDE_LOCATION = HintCode(
     'INVALID_LANGUAGE_VERSION_OVERRIDE',
-    "The language version override must be before any declaration or directive.",
+    "The language version override must be before any declaration or "
+        "directive.",
     correctionMessage:
         "Try moving the language version override to the top of the file.",
     uniqueName: 'INVALID_LANGUAGE_VERSION_OVERRIDE_LOCATION',
@@ -1088,9 +1124,11 @@
    */
   static const HintCode INVALID_LANGUAGE_VERSION_OVERRIDE_LOWER_CASE = HintCode(
     'INVALID_LANGUAGE_VERSION_OVERRIDE',
-    "The Dart language version override comment must be specified with the word 'dart' in all lower case",
+    "The Dart language version override comment must be specified with the "
+        "word 'dart' in all lower case",
     correctionMessage:
-        "Specify a Dart language version override with a comment like '// @dart = 2.0'.",
+        "Specify a Dart language version override with a comment like '// "
+        "@dart = 2.0'.",
     uniqueName: 'INVALID_LANGUAGE_VERSION_OVERRIDE_LOWER_CASE',
   );
 
@@ -1108,9 +1146,11 @@
    */
   static const HintCode INVALID_LANGUAGE_VERSION_OVERRIDE_NUMBER = HintCode(
     'INVALID_LANGUAGE_VERSION_OVERRIDE',
-    "The Dart language version override comment must be specified with a version number, like '2.0', after the '=' character.",
+    "The Dart language version override comment must be specified with a "
+        "version number, like '2.0', after the '=' character.",
     correctionMessage:
-        "Specify a Dart language version override with a comment like '// @dart = 2.0'.",
+        "Specify a Dart language version override with a comment like '// "
+        "@dart = 2.0'.",
     uniqueName: 'INVALID_LANGUAGE_VERSION_OVERRIDE_NUMBER',
   );
 
@@ -1130,7 +1170,8 @@
     'INVALID_LANGUAGE_VERSION_OVERRIDE',
     "The Dart language version override number can't be prefixed with a letter",
     correctionMessage:
-        "Specify a Dart language version override with a comment like '// @dart = 2.0'.",
+        "Specify a Dart language version override with a comment like '// "
+        "@dart = 2.0'.",
     uniqueName: 'INVALID_LANGUAGE_VERSION_OVERRIDE_PREFIX',
   );
 
@@ -1149,9 +1190,11 @@
   static const HintCode INVALID_LANGUAGE_VERSION_OVERRIDE_TRAILING_CHARACTERS =
       HintCode(
     'INVALID_LANGUAGE_VERSION_OVERRIDE',
-    "The Dart language version override comment can't be followed by any non-whitespace characters",
+    "The Dart language version override comment can't be followed by any "
+        "non-whitespace characters",
     correctionMessage:
-        "Specify a Dart language version override with a comment like '// @dart = 2.0'.",
+        "Specify a Dart language version override with a comment like '// "
+        "@dart = 2.0'.",
     uniqueName: 'INVALID_LANGUAGE_VERSION_OVERRIDE_TRAILING_CHARACTERS',
   );
 
@@ -1170,9 +1213,11 @@
   static const HintCode INVALID_LANGUAGE_VERSION_OVERRIDE_TWO_SLASHES =
       HintCode(
     'INVALID_LANGUAGE_VERSION_OVERRIDE',
-    "The Dart language version override comment must be specified with exactly two slashes.",
+    "The Dart language version override comment must be specified with exactly "
+        "two slashes.",
     correctionMessage:
-        "Specify a Dart language version override with a comment like '// @dart = 2.0'.",
+        "Specify a Dart language version override with a comment like '// "
+        "@dart = 2.0'.",
     uniqueName: 'INVALID_LANGUAGE_VERSION_OVERRIDE_TWO_SLASHES',
   );
 
@@ -1245,7 +1290,8 @@
    */
   static const HintCode INVALID_NON_VIRTUAL_ANNOTATION = HintCode(
     'INVALID_NON_VIRTUAL_ANNOTATION',
-    "The annotation '@nonVirtual' can only be applied to a concrete instance member.",
+    "The annotation '@nonVirtual' can only be applied to a concrete instance "
+        "member.",
     correctionMessage: "Try removing @nonVirtual.",
   );
 
@@ -1259,7 +1305,8 @@
    */
   static const HintCode INVALID_OVERRIDE_OF_NON_VIRTUAL_MEMBER = HintCode(
     'INVALID_OVERRIDE_OF_NON_VIRTUAL_MEMBER',
-    "The member '{0}' is declared non-virtual in '{1}' and can't be overridden in subclasses.",
+    "The member '{0}' is declared non-virtual in '{1}' and can't be overridden "
+        "in subclasses.",
   );
 
   /**
@@ -1271,7 +1318,8 @@
    */
   static const HintCode INVALID_REQUIRED_NAMED_PARAM = HintCode(
     'INVALID_REQUIRED_NAMED_PARAM',
-    "The type parameter '{0}' is annotated with @required but only named parameters without a default value can be annotated with it.",
+    "The type parameter '{0}' is annotated with @required but only named "
+        "parameters without a default value can be annotated with it.",
     correctionMessage: "Remove @required.",
   );
 
@@ -1284,7 +1332,8 @@
    */
   static const HintCode INVALID_REQUIRED_OPTIONAL_POSITIONAL_PARAM = HintCode(
     'INVALID_REQUIRED_OPTIONAL_POSITIONAL_PARAM',
-    "Incorrect use of the annotation @required on the optional positional parameter '{0}'. Optional positional parameters cannot be required.",
+    "Incorrect use of the annotation @required on the optional positional "
+        "parameter '{0}'. Optional positional parameters cannot be required.",
     correctionMessage: "Remove @required.",
   );
 
@@ -1297,7 +1346,8 @@
    */
   static const HintCode INVALID_REQUIRED_POSITIONAL_PARAM = HintCode(
     'INVALID_REQUIRED_POSITIONAL_PARAM',
-    "Redundant use of the annotation @required on the required positional parameter '{0}'.",
+    "Redundant use of the annotation @required on the required positional "
+        "parameter '{0}'.",
     correctionMessage: "Remove @required.",
   );
 
@@ -1335,7 +1385,8 @@
    */
   static const HintCode INVALID_USE_OF_PROTECTED_MEMBER = HintCode(
     'INVALID_USE_OF_PROTECTED_MEMBER',
-    "The member '{0}' can only be used within instance members of subclasses of '{1}'.",
+    "The member '{0}' can only be used within instance members of subclasses "
+        "of '{1}'.",
   );
 
   /**
@@ -1460,7 +1511,8 @@
   // ```
   static const HintCode INVALID_VISIBILITY_ANNOTATION = HintCode(
     'INVALID_VISIBILITY_ANNOTATION',
-    "The member '{0}' is annotated with '{1}', but this annotation is only meaningful on declarations of public members.",
+    "The member '{0}' is annotated with '{1}', but this annotation is only "
+        "meaningful on declarations of public members.",
     hasPublishedDocs: true,
   );
 
@@ -1495,7 +1547,8 @@
   // ```
   static const HintCode INVALID_VISIBLE_FOR_OVERRIDING_ANNOTATION = HintCode(
     'INVALID_VISIBLE_FOR_OVERRIDING_ANNOTATION',
-    "The annotation 'visibleForOverriding' can only be applied to a public instance member that can be overridden.",
+    "The annotation 'visibleForOverriding' can only be applied to a public "
+        "instance member that can be overridden.",
     hasPublishedDocs: true,
   );
 
@@ -1593,7 +1646,8 @@
   // `null` is the appropriate value.
   static const HintCode MISSING_RETURN = HintCode(
     'MISSING_RETURN',
-    "This function has a return type of '{0}', but doesn't end with a return statement.",
+    "This function has a return type of '{0}', but doesn't end with a return "
+        "statement.",
     correctionMessage:
         "Try adding a return statement, or changing the return type to 'void'.",
     hasPublishedDocs: true,
@@ -1641,9 +1695,12 @@
   // of the sealed class.
   static const HintCode MIXIN_ON_SEALED_CLASS = HintCode(
     'MIXIN_ON_SEALED_CLASS',
-    "The class '{0}' shouldn't be used as a mixin constraint because it is sealed, and any class mixing in this mixin must have '{0}' as a superclass.",
+    "The class '{0}' shouldn't be used as a mixin constraint because it is "
+        "sealed, and any class mixing in this mixin must have '{0}' as a "
+        "superclass.",
     correctionMessage:
-        "Try composing with this class, or refer to its documentation for more information.",
+        "Try composing with this class, or refer to its documentation for more "
+        "information.",
     hasPublishedDocs: true,
   );
 
@@ -1703,7 +1760,9 @@
   // ```
   static const HintCode MUST_BE_IMMUTABLE = HintCode(
     'MUST_BE_IMMUTABLE',
-    "This class (or a class that this class inherits from) is marked as '@immutable', but one or more of its instance fields aren't final: {0}",
+    "This class (or a class that this class inherits from) is marked as "
+        "'@immutable', but one or more of its instance fields aren't final: "
+        "{0}",
     hasPublishedDocs: true,
   );
 
@@ -1757,7 +1816,8 @@
   // ```
   static const HintCode MUST_CALL_SUPER = HintCode(
     'MUST_CALL_SUPER',
-    "This method overrides a method annotated as '@mustCallSuper' in '{0}', but doesn't invoke the overridden method.",
+    "This method overrides a method annotated as '@mustCallSuper' in '{0}', "
+        "but doesn't invoke the overridden method.",
     hasPublishedDocs: true,
   );
 
@@ -1807,7 +1867,8 @@
   // ```
   static const HintCode NON_CONST_CALL_TO_LITERAL_CONSTRUCTOR = HintCode(
     'NON_CONST_CALL_TO_LITERAL_CONSTRUCTOR',
-    "This instance creation must be 'const', because the {0} constructor is marked as '@literal'.",
+    "This instance creation must be 'const', because the {0} constructor is "
+        "marked as '@literal'.",
     correctionMessage: "Try adding a 'const' keyword.",
     hasPublishedDocs: true,
   );
@@ -1822,7 +1883,8 @@
   static const HintCode NON_CONST_CALL_TO_LITERAL_CONSTRUCTOR_USING_NEW =
       HintCode(
     'NON_CONST_CALL_TO_LITERAL_CONSTRUCTOR',
-    "This instance creation must be 'const', because the {0} constructor is marked as '@literal'.",
+    "This instance creation must be 'const', because the {0} constructor is "
+        "marked as '@literal'.",
     correctionMessage: "Try replacing the 'new' keyword with 'const'.",
     hasPublishedDocs: true,
     uniqueName: 'NON_CONST_CALL_TO_LITERAL_CONSTRUCTOR_USING_NEW',
@@ -1866,7 +1928,8 @@
   // ```
   static const HintCode NULLABLE_TYPE_IN_CATCH_CLAUSE = HintCode(
     'NULLABLE_TYPE_IN_CATCH_CLAUSE',
-    "A potentially nullable type can't be used in an 'on' clause because it isn't valid to throw a nullable expression.",
+    "A potentially nullable type can't be used in an 'on' clause because it "
+        "isn't valid to throw a nullable expression.",
     correctionMessage: "Try using a non-nullable type.",
     hasPublishedDocs: true,
   );
@@ -1907,7 +1970,8 @@
   // ```
   static const HintCode NULL_ARGUMENT_TO_NON_NULL_TYPE = HintCode(
     'NULL_ARGUMENT_TO_NON_NULL_TYPE',
-    "'{0}' shouldn't be called with a null argument for the non-nullable type argument '{1}'.",
+    "'{0}' shouldn't be called with a null argument for the non-nullable type "
+        "argument '{1}'.",
     correctionMessage: "Try adding a non-null argument.",
     hasPublishedDocs: true,
   );
@@ -1927,9 +1991,11 @@
    */
   static const HintCode NULL_AWARE_IN_CONDITION = HintCode(
     'NULL_AWARE_IN_CONDITION',
-    "The value of the '?.' operator can be 'null', which isn't appropriate in a condition.",
+    "The value of the '?.' operator can be 'null', which isn't appropriate in "
+        "a condition.",
     correctionMessage:
-        "Try replacing the '?.' with a '.', testing the left-hand side for null if necessary.",
+        "Try replacing the '?.' with a '.', testing the left-hand side for "
+        "null if necessary.",
   );
 
   /**
@@ -1938,7 +2004,8 @@
    */
   static const HintCode NULL_AWARE_IN_LOGICAL_OPERATOR = HintCode(
     'NULL_AWARE_IN_LOGICAL_OPERATOR',
-    "The value of the '?.' operator can be 'null', which isn't appropriate as an operand of a logical operator.",
+    "The value of the '?.' operator can be 'null', which isn't appropriate as "
+        "an operand of a logical operator.",
   );
 
   /**
@@ -1947,7 +2014,8 @@
    */
   static const HintCode NULL_CHECK_ALWAYS_FAILS = HintCode(
     'NULL_CHECK_ALWAYS_FAILS',
-    "This null-check will always throw an exception because the expression will always evaluate to 'null'.",
+    "This null-check will always throw an exception because the expression "
+        "will always evaluate to 'null'.",
   );
 
   /**
@@ -1959,7 +2027,8 @@
     'OVERRIDE_ON_NON_OVERRIDING_MEMBER',
     "The field doesn't override an inherited getter or setter.",
     correctionMessage:
-        "Try updating this class to match the superclass, or removing the override annotation.",
+        "Try updating this class to match the superclass, or removing the "
+        "override annotation.",
     hasPublishedDocs: true,
     uniqueName: 'OVERRIDE_ON_NON_OVERRIDING_FIELD',
   );
@@ -1973,7 +2042,8 @@
     'OVERRIDE_ON_NON_OVERRIDING_MEMBER',
     "The getter doesn't override an inherited getter.",
     correctionMessage:
-        "Try updating this class to match the superclass, or removing the override annotation.",
+        "Try updating this class to match the superclass, or removing the "
+        "override annotation.",
     hasPublishedDocs: true,
     uniqueName: 'OVERRIDE_ON_NON_OVERRIDING_GETTER',
   );
@@ -2021,7 +2091,8 @@
     'OVERRIDE_ON_NON_OVERRIDING_MEMBER',
     "The method doesn't override an inherited method.",
     correctionMessage:
-        "Try updating this class to match the superclass, or removing the override annotation.",
+        "Try updating this class to match the superclass, or removing the "
+        "override annotation.",
     hasPublishedDocs: true,
     uniqueName: 'OVERRIDE_ON_NON_OVERRIDING_METHOD',
   );
@@ -2035,7 +2106,8 @@
     'OVERRIDE_ON_NON_OVERRIDING_MEMBER',
     "The setter doesn't override an inherited setter.",
     correctionMessage:
-        "Try updating this class to match the superclass, or removing the override annotation.",
+        "Try updating this class to match the superclass, or removing the "
+        "override annotation.",
     hasPublishedDocs: true,
     uniqueName: 'OVERRIDE_ON_NON_OVERRIDING_SETTER',
   );
@@ -2078,7 +2150,8 @@
    */
   static const HintCode RETURN_OF_DO_NOT_STORE = HintCode(
     'RETURN_OF_DO_NOT_STORE',
-    "'{0}' is annotated with 'doNotStore' and shouldn't be returned unless '{1}' is also annotated.",
+    "'{0}' is annotated with 'doNotStore' and shouldn't be returned unless "
+        "'{1}' is also annotated.",
     correctionMessage: "Annotate '{1}' with 'doNotStore'.",
   );
 
@@ -2138,7 +2211,8 @@
   // ```
   static const HintCode RETURN_OF_INVALID_TYPE_FROM_CATCH_ERROR = HintCode(
     'INVALID_RETURN_TYPE_FOR_CATCH_ERROR',
-    "A value of type '{0}' can't be returned by the 'onError' handler because it must be assignable to '{1}'.",
+    "A value of type '{0}' can't be returned by the 'onError' handler because "
+        "it must be assignable to '{1}'.",
     hasPublishedDocs: true,
     uniqueName: 'RETURN_OF_INVALID_TYPE_FROM_CATCH_ERROR',
   );
@@ -2150,7 +2224,8 @@
    */
   static const HintCode RETURN_TYPE_INVALID_FOR_CATCH_ERROR = HintCode(
     'INVALID_RETURN_TYPE_FOR_CATCH_ERROR',
-    "The return type '{0}' isn't assignable to '{1}', as required by 'Future.catchError'.",
+    "The return type '{0}' isn't assignable to '{1}', as required by "
+        "'Future.catchError'.",
     hasPublishedDocs: true,
     uniqueName: 'RETURN_TYPE_INVALID_FOR_CATCH_ERROR',
   );
@@ -2204,7 +2279,8 @@
   // ```
   static const HintCode SDK_VERSION_ASYNC_EXPORTED_FROM_CORE = HintCode(
     'SDK_VERSION_ASYNC_EXPORTED_FROM_CORE',
-    "The class '{0}' wasn't exported from 'dart:core' until version 2.1, but this code is required to be able to run on earlier versions.",
+    "The class '{0}' wasn't exported from 'dart:core' until version 2.1, but "
+        "this code is required to be able to run on earlier versions.",
     correctionMessage:
         "Try either importing 'dart:async' or updating the SDK constraints.",
     hasPublishedDocs: true,
@@ -2260,7 +2336,9 @@
   // ```
   static const HintCode SDK_VERSION_AS_EXPRESSION_IN_CONST_CONTEXT = HintCode(
     'SDK_VERSION_AS_EXPRESSION_IN_CONST_CONTEXT',
-    "The use of an as expression in a constant expression wasn't supported until version 2.3.2, but this code is required to be able to run on earlier versions.",
+    "The use of an as expression in a constant expression wasn't supported "
+        "until version 2.3.2, but this code is required to be able to run on "
+        "earlier versions.",
     correctionMessage: "Try updating the SDK constraints.",
     hasPublishedDocs: true,
   );
@@ -2318,7 +2396,9 @@
   // ```
   static const HintCode SDK_VERSION_BOOL_OPERATOR_IN_CONST_CONTEXT = HintCode(
     'SDK_VERSION_BOOL_OPERATOR_IN_CONST_CONTEXT',
-    "The use of the operator '{0}' for 'bool' operands in a constant context wasn't supported until version 2.3.2, but this code is required to be able to run on earlier versions.",
+    "The use of the operator '{0}' for 'bool' operands in a constant context "
+        "wasn't supported until version 2.3.2, but this code is required to be "
+        "able to run on earlier versions.",
     correctionMessage: "Try updating the SDK constraints.",
     hasPublishedDocs: true,
   );
@@ -2376,9 +2456,11 @@
   // ```
   static const HintCode SDK_VERSION_CONSTRUCTOR_TEAROFFS = HintCode(
     'SDK_VERSION_CONSTRUCTOR_TEAROFFS',
-    "Tearing off a constructor requires the 'constructor-tearoffs' language feature.",
+    "Tearing off a constructor requires the 'constructor-tearoffs' language "
+        "feature.",
     correctionMessage:
-        "Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.",
+        "Try updating your pubspec.yaml to set the minimum SDK constraint to "
+        "2.15 or higher, and running 'pub get'.",
     hasPublishedDocs: true,
   );
 
@@ -2438,7 +2520,9 @@
   // ```
   static const HintCode SDK_VERSION_EQ_EQ_OPERATOR_IN_CONST_CONTEXT = HintCode(
     'SDK_VERSION_EQ_EQ_OPERATOR_IN_CONST_CONTEXT',
-    "Using the operator '==' for non-primitive types wasn't supported until version 2.3.2, but this code is required to be able to run on earlier versions.",
+    "Using the operator '==' for non-primitive types wasn't supported until "
+        "version 2.3.2, but this code is required to be able to run on earlier "
+        "versions.",
     correctionMessage: "Try updating the SDK constraints.",
     hasPublishedDocs: true,
   );
@@ -2498,7 +2582,8 @@
   // ```
   static const HintCode SDK_VERSION_EXTENSION_METHODS = HintCode(
     'SDK_VERSION_EXTENSION_METHODS',
-    "Extension methods weren't supported until version 2.6.0, but this code is required to be able to run on earlier versions.",
+    "Extension methods weren't supported until version 2.6.0, but this code is "
+        "required to be able to run on earlier versions.",
     correctionMessage: "Try updating the SDK constraints.",
     hasPublishedDocs: true,
   );
@@ -2557,7 +2642,8 @@
   // ```
   static const HintCode SDK_VERSION_GT_GT_GT_OPERATOR = HintCode(
     'SDK_VERSION_GT_GT_GT_OPERATOR',
-    "The operator '>>>' wasn't supported until version 2.14.0, but this code is required to be able to run on earlier versions.",
+    "The operator '>>>' wasn't supported until version 2.14.0, but this code "
+        "is required to be able to run on earlier versions.",
     correctionMessage: "Try updating the SDK constraints.",
     hasPublishedDocs: true,
   );
@@ -2613,7 +2699,9 @@
   // ```
   static const HintCode SDK_VERSION_IS_EXPRESSION_IN_CONST_CONTEXT = HintCode(
     'SDK_VERSION_IS_EXPRESSION_IN_CONST_CONTEXT',
-    "The use of an is expression in a constant context wasn't supported until version 2.3.2, but this code is required to be able to run on earlier versions.",
+    "The use of an is expression in a constant context wasn't supported until "
+        "version 2.3.2, but this code is required to be able to run on earlier "
+        "versions.",
     correctionMessage: "Try updating the SDK constraints.",
     hasPublishedDocs: true,
   );
@@ -2665,7 +2753,8 @@
   // ```
   static const HintCode SDK_VERSION_NEVER = HintCode(
     'SDK_VERSION_NEVER',
-    "The type 'Never' wasn't supported until version 2.12.0, but this code is required to be able to run on earlier versions.",
+    "The type 'Never' wasn't supported until version 2.12.0, but this code is "
+        "required to be able to run on earlier versions.",
     correctionMessage: "Try updating the SDK constraints.",
     hasPublishedDocs: true,
   );
@@ -2716,7 +2805,8 @@
   // ```
   static const HintCode SDK_VERSION_SET_LITERAL = HintCode(
     'SDK_VERSION_SET_LITERAL',
-    "Set literals weren't supported until version 2.2, but this code is required to be able to run on earlier versions.",
+    "Set literals weren't supported until version 2.2, but this code is "
+        "required to be able to run on earlier versions.",
     correctionMessage: "Try updating the SDK constraints.",
     hasPublishedDocs: true,
   );
@@ -2776,7 +2866,8 @@
   // ```
   static const HintCode SDK_VERSION_UI_AS_CODE = HintCode(
     'SDK_VERSION_UI_AS_CODE',
-    "The for, if, and spread elements weren't supported until version 2.3.0, but this code is required to be able to run on earlier versions.",
+    "The for, if, and spread elements weren't supported until version 2.3.0, "
+        "but this code is required to be able to run on earlier versions.",
     correctionMessage: "Try updating the SDK constraints.",
     hasPublishedDocs: true,
   );
@@ -2838,7 +2929,9 @@
   // ```
   static const HintCode SDK_VERSION_UI_AS_CODE_IN_CONST_CONTEXT = HintCode(
     'SDK_VERSION_UI_AS_CODE_IN_CONST_CONTEXT',
-    "The if and spread elements weren't supported in constant expressions until version 2.5.0, but this code is required to be able to run on earlier versions.",
+    "The if and spread elements weren't supported in constant expressions "
+        "until version 2.5.0, but this code is required to be able to run on "
+        "earlier versions.",
     correctionMessage: "Try updating the SDK constraints.",
     hasPublishedDocs: true,
   );
@@ -2907,9 +3000,11 @@
   // the same package as the sealed class.
   static const HintCode SUBTYPE_OF_SEALED_CLASS = HintCode(
     'SUBTYPE_OF_SEALED_CLASS',
-    "The class '{0}' shouldn't be extended, mixed in, or implemented because it's sealed.",
+    "The class '{0}' shouldn't be extended, mixed in, or implemented because "
+        "it's sealed.",
     correctionMessage:
-        "Try composing instead of inheriting, or refer to the documentation of '{0}' for more information.",
+        "Try composing instead of inheriting, or refer to the documentation of "
+        "'{0}' for more information.",
     hasPublishedDocs: true,
   );
 
@@ -2951,9 +3046,11 @@
   // ```
   static const HintCode TEXT_DIRECTION_CODE_POINT_IN_COMMENT = HintCode(
     'TEXT_DIRECTION_CODE_POINT_IN_COMMENT',
-    "The Unicode code point 'U+{0}' changes the appearance of text from how it's interpreted by the compiler.",
+    "The Unicode code point 'U+{0}' changes the appearance of text from how "
+        "it's interpreted by the compiler.",
     correctionMessage:
-        "Try removing the code point or using the Unicode escape sequence '\\u{0}'.",
+        "Try removing the code point or using the Unicode escape sequence "
+        "'\\u{0}'.",
   );
 
   /**
@@ -2994,9 +3091,11 @@
   // ```
   static const HintCode TEXT_DIRECTION_CODE_POINT_IN_LITERAL = HintCode(
     'TEXT_DIRECTION_CODE_POINT_IN_LITERAL',
-    "The Unicode code point 'U+{0}' changes the appearance of text from how it's interpreted by the compiler.",
+    "The Unicode code point 'U+{0}' changes the appearance of text from how "
+        "it's interpreted by the compiler.",
     correctionMessage:
-        "Try removing the code point or using the Unicode escape sequence '\\u{0}'.",
+        "Try removing the code point or using the Unicode escape sequence "
+        "'\\u{0}'.",
   );
 
   /**
@@ -3190,7 +3289,8 @@
     'UNIGNORABLE_IGNORE',
     "The diagnostic '{0}' can't be ignored.",
     correctionMessage:
-        "Try removing the name from the list, or removing the whole comment if this is the only name in the list.",
+        "Try removing the name from the list, or removing the whole comment if "
+        "this is the only name in the list.",
   );
 
   /**
@@ -3238,9 +3338,11 @@
    */
   static const HintCode UNNECESSARY_IGNORE = HintCode(
     'UNNECESSARY_IGNORE',
-    "The diagnostic '{0}' isn't produced at this location so it doesn't need to be ignored.",
+    "The diagnostic '{0}' isn't produced at this location so it doesn't need "
+        "to be ignored.",
     correctionMessage:
-        "Try removing the name from the list, or removing the whole comment if this is the only name in the list.",
+        "Try removing the name from the list, or removing the whole comment if "
+        "this is the only name in the list.",
   );
 
   /**
@@ -3292,7 +3394,8 @@
   // the missing references to those names.
   static const HintCode UNNECESSARY_IMPORT = HintCode(
     'UNNECESSARY_IMPORT',
-    "The import of '{0}' is unnecessary because all of the used elements are also provided by the import of '{1}'.",
+    "The import of '{0}' is unnecessary because all of the used elements are "
+        "also provided by the import of '{1}'.",
     correctionMessage: "Try removing the import directive.",
     hasPublishedDocs: true,
   );
@@ -3408,7 +3511,8 @@
     'UNNECESSARY_NULL_COMPARISON',
     "The operand can't be null, so the condition is always false.",
     correctionMessage:
-        "Try removing the condition, an enclosing condition, or the whole conditional statement.",
+        "Try removing the condition, an enclosing condition, or the whole "
+        "conditional statement.",
     hasPublishedDocs: true,
     uniqueName: 'UNNECESSARY_NULL_COMPARISON_FALSE',
   );
@@ -3548,7 +3652,8 @@
   // ```
   static const HintCode UNUSED_CATCH_CLAUSE = HintCode(
     'UNUSED_CATCH_CLAUSE',
-    "The exception variable '{0}' isn't used, so the 'catch' clause can be removed.",
+    "The exception variable '{0}' isn't used, so the 'catch' clause can be "
+        "removed.",
     correctionMessage: "Try removing the catch clause.",
     hasPublishedDocs: true,
   );
@@ -3790,7 +3895,8 @@
     'UNUSED_LABEL',
     "The label '{0}' isn't used.",
     correctionMessage:
-        "Try removing the label, or using it in either a 'break' or 'continue' statement.",
+        "Try removing the label, or using it in either a 'break' or 'continue' "
+        "statement.",
     hasPublishedDocs: true,
   );
 
@@ -3900,7 +4006,8 @@
     'UNUSED_RESULT',
     "The value of '{0}' should be used.",
     correctionMessage:
-        "Try using the result by invoking a member, passing it to a function, or returning it from this function.",
+        "Try using the result by invoking a member, passing it to a function, "
+        "or returning it from this function.",
     hasPublishedDocs: true,
   );
 
@@ -3917,7 +4024,8 @@
     'UNUSED_RESULT',
     "'{0}' should be used. {1}.",
     correctionMessage:
-        "Try using the result by invoking a member, passing it to a function, or returning it from this function.",
+        "Try using the result by invoking a member, passing it to a function, "
+        "or returning it from this function.",
     hasPublishedDocs: true,
     uniqueName: 'UNUSED_RESULT_WITH_MESSAGE',
   );
diff --git a/pkg/analyzer/lib/src/dart/error/lint_codes.dart b/pkg/analyzer/lib/src/dart/error/lint_codes.dart
index 45983c4..32b5cff 100644
--- a/pkg/analyzer/lib/src/dart/error/lint_codes.dart
+++ b/pkg/analyzer/lib/src/dart/error/lint_codes.dart
@@ -13,11 +13,10 @@
   const LintCode(
     String name,
     String problemMessage, {
-    @Deprecated('Use correctionMessage instead') String? correction,
     String? correctionMessage,
     String? uniqueName,
   }) : super(
-          correctionMessage: correctionMessage ?? correction,
+          correctionMessage: correctionMessage,
           problemMessage: problemMessage,
           name: name,
           uniqueName: uniqueName ?? 'LintCode.$name',
@@ -29,9 +28,6 @@
   @override
   int get hashCode => uniqueName.hashCode;
 
-  @Deprecated('Use problemMessage instead')
-  String get message => problemMessage;
-
   @override
   ErrorType get type => ErrorType.LINT;
 
diff --git a/pkg/analyzer/lib/src/dart/error/syntactic_errors.g.dart b/pkg/analyzer/lib/src/dart/error/syntactic_errors.g.dart
index 0bec5ea..1a6f7b2 100644
--- a/pkg/analyzer/lib/src/dart/error/syntactic_errors.g.dart
+++ b/pkg/analyzer/lib/src/dart/error/syntactic_errors.g.dart
@@ -142,7 +142,8 @@
     'ABSTRACT_CLASS_MEMBER',
     "Members of classes can't be declared to be 'abstract'.",
     correctionMessage:
-        "Try removing the 'abstract' keyword. You can add the 'abstract' keyword before the class declaration.",
+        "Try removing the 'abstract' keyword. You can add the 'abstract' "
+        "keyword before the class declaration.",
   );
 
   static const ParserErrorCode ABSTRACT_ENUM = ParserErrorCode(
@@ -217,12 +218,14 @@
   static const ParserErrorCode ASYNC_KEYWORD_USED_AS_IDENTIFIER =
       ParserErrorCode(
     'ASYNC_KEYWORD_USED_AS_IDENTIFIER',
-    "The keywords 'await' and 'yield' can't be used as identifiers in an asynchronous or generator function.",
+    "The keywords 'await' and 'yield' can't be used as identifiers in an "
+        "asynchronous or generator function.",
   );
 
   static const ParserErrorCode BINARY_OPERATOR_WRITTEN_OUT = ParserErrorCode(
     'BINARY_OPERATOR_WRITTEN_OUT',
-    "Binary operator '{0}' is written as '{1}' instead of the written out word.",
+    "Binary operator '{0}' is written as '{1}' instead of the written out "
+        "word.",
     correctionMessage: "Try replacing '{0}' with '{1}'.",
   );
 
@@ -236,14 +239,16 @@
     'CATCH_SYNTAX',
     "'catch' must be followed by '(identifier)' or '(identifier, identifier)'.",
     correctionMessage:
-        "No types are needed, the first is given by 'on', the second is always 'StackTrace'.",
+        "No types are needed, the first is given by 'on', the second is always "
+        "'StackTrace'.",
   );
 
   static const ParserErrorCode CATCH_SYNTAX_EXTRA_PARAMETERS = ParserErrorCode(
     'CATCH_SYNTAX_EXTRA_PARAMETERS',
     "'catch' must be followed by '(identifier)' or '(identifier, identifier)'.",
     correctionMessage:
-        "No types are needed, the first is given by 'on', the second is always 'StackTrace'.",
+        "No types are needed, the first is given by 'on', the second is always "
+        "'StackTrace'.",
   );
 
   static const ParserErrorCode CLASS_IN_CLASS = ParserErrorCode(
@@ -273,7 +278,8 @@
   static const ParserErrorCode CONSTRUCTOR_WITH_TYPE_ARGUMENTS =
       ParserErrorCode(
     'CONSTRUCTOR_WITH_TYPE_ARGUMENTS',
-    "A constructor invocation can't have type arguments after the constructor name.",
+    "A constructor invocation can't have type arguments after the constructor "
+        "name.",
     correctionMessage:
         "Try removing the type arguments or placing them after the class name.",
   );
@@ -288,7 +294,9 @@
     'CONST_CLASS',
     "Classes can't be declared to be 'const'.",
     correctionMessage:
-        "Try removing the 'const' keyword. If you're trying to indicate that instances of the class can be constants, place the 'const' keyword on  the class' constructor(s).",
+        "Try removing the 'const' keyword. If you're trying to indicate that "
+        "instances of the class can be constants, place the 'const' keyword on "
+        " the class' constructor(s).",
   );
 
   static const ParserErrorCode CONST_CONSTRUCTOR_WITH_BODY = ParserErrorCode(
@@ -307,7 +315,8 @@
     'CONST_FACTORY',
     "Only redirecting factory constructors can be declared to be 'const'.",
     correctionMessage:
-        "Try removing the 'const' keyword, or replacing the body with '=' followed by a valid target.",
+        "Try removing the 'const' keyword, or replacing the body with '=' "
+        "followed by a valid target.",
   );
 
   static const ParserErrorCode CONST_METHOD = ParserErrorCode(
@@ -332,7 +341,8 @@
     'CONTINUE_WITHOUT_LABEL_IN_CASE',
     "A continue statement in a switch statement must have a label as a target.",
     correctionMessage:
-        "Try adding a label associated with one of the case clauses to the continue statement.",
+        "Try adding a label associated with one of the case clauses to the "
+        "continue statement.",
   );
 
   static const ParserErrorCode COVARIANT_AND_STATIC = ParserErrorCode(
@@ -398,7 +408,8 @@
 
   static const ParserErrorCode DEFERRED_AFTER_PREFIX = ParserErrorCode(
     'DEFERRED_AFTER_PREFIX',
-    "The deferred keyword should come immediately before the prefix ('as' clause).",
+    "The deferred keyword should come immediately before the prefix ('as' "
+        "clause).",
     correctionMessage: "Try moving the deferred keyword before the prefix.",
   );
 
@@ -456,7 +467,8 @@
   static const ParserErrorCode EQUALITY_CANNOT_BE_EQUALITY_OPERAND =
       ParserErrorCode(
     'EQUALITY_CANNOT_BE_EQUALITY_OPERAND',
-    "A comparison expression can't be an operand of another comparison expression.",
+    "A comparison expression can't be an operand of another comparison "
+        "expression.",
     correctionMessage: "Try putting parentheses around one of the comparisons.",
   );
 
@@ -533,7 +545,8 @@
     'EXPERIMENT_NOT_ENABLED',
     "This requires the '{0}' language feature to be enabled.",
     correctionMessage:
-        "Try updating your pubspec.yaml to set the minimum SDK constraint to {1} or higher, and running 'pub get'.",
+        "Try updating your pubspec.yaml to set the minimum SDK constraint to "
+        "{1} or higher, and running 'pub get'.",
   );
 
   static const ParserErrorCode EXPORT_DIRECTIVE_AFTER_PART_DIRECTIVE =
@@ -649,7 +662,8 @@
     'EXTERNAL_CONSTRUCTOR_WITH_BODY',
     "External constructors can't have a body.",
     correctionMessage:
-        "Try removing the body of the constructor, or removing the keyword 'external'.",
+        "Try removing the body of the constructor, or removing the keyword "
+        "'external'.",
   );
 
   static const ParserErrorCode EXTERNAL_CONSTRUCTOR_WITH_INITIALIZER =
@@ -674,21 +688,24 @@
     'EXTERNAL_FACTORY_WITH_BODY',
     "External factories can't have a body.",
     correctionMessage:
-        "Try removing the body of the factory, or removing the keyword 'external'.",
+        "Try removing the body of the factory, or removing the keyword "
+        "'external'.",
   );
 
   static const ParserErrorCode EXTERNAL_FIELD = ParserErrorCode(
     'EXTERNAL_FIELD',
     "Fields can't be declared to be 'external'.",
     correctionMessage:
-        "Try removing the keyword 'external', or replacing the field by an external getter and/or setter.",
+        "Try removing the keyword 'external', or replacing the field by an "
+        "external getter and/or setter.",
   );
 
   static const ParserErrorCode EXTERNAL_GETTER_WITH_BODY = ParserErrorCode(
     'EXTERNAL_GETTER_WITH_BODY',
     "External getters can't have a body.",
     correctionMessage:
-        "Try removing the body of the getter, or removing the keyword 'external'.",
+        "Try removing the body of the getter, or removing the keyword "
+        "'external'.",
   );
 
   static const ParserErrorCode EXTERNAL_LATE_FIELD = ParserErrorCode(
@@ -706,14 +723,16 @@
     'EXTERNAL_OPERATOR_WITH_BODY',
     "External operators can't have a body.",
     correctionMessage:
-        "Try removing the body of the operator, or removing the keyword 'external'.",
+        "Try removing the body of the operator, or removing the keyword "
+        "'external'.",
   );
 
   static const ParserErrorCode EXTERNAL_SETTER_WITH_BODY = ParserErrorCode(
     'EXTERNAL_SETTER_WITH_BODY',
     "External setters can't have a body.",
     correctionMessage:
-        "Try removing the body of the setter, or removing the keyword 'external'.",
+        "Try removing the body of the setter, or removing the keyword "
+        "'external'.",
   );
 
   static const ParserErrorCode EXTERNAL_TYPEDEF = ParserErrorCode(
@@ -744,7 +763,8 @@
     'FACTORY_WITH_INITIALIZERS',
     "A 'factory' constructor can't have initializers.",
     correctionMessage:
-        "Try removing the 'factory' keyword to make this a generative constructor, or removing the initializers.",
+        "Try removing the 'factory' keyword to make this a generative "
+        "constructor, or removing the initializers.",
   );
 
   static const ParserErrorCode FIELD_INITIALIZED_OUTSIDE_DECLARING_CLASS =
@@ -752,7 +772,8 @@
     'FIELD_INITIALIZED_OUTSIDE_DECLARING_CLASS',
     "A field can only be initialized in its declaring class",
     correctionMessage:
-        "Try passing a value into the superclass constructor, or moving the initialization into the constructor body.",
+        "Try passing a value into the superclass constructor, or moving the "
+        "initialization into the constructor body.",
   );
 
   static const ParserErrorCode FIELD_INITIALIZER_OUTSIDE_CONSTRUCTOR =
@@ -772,9 +793,11 @@
   static const ParserErrorCode FINAL_AND_COVARIANT_LATE_WITH_INITIALIZER =
       ParserErrorCode(
     'FINAL_AND_COVARIANT_LATE_WITH_INITIALIZER',
-    "Members marked 'late' with an initializer can't be declared to be both 'final' and 'covariant'.",
+    "Members marked 'late' with an initializer can't be declared to be both "
+        "'final' and 'covariant'.",
     correctionMessage:
-        "Try removing either the 'final' or 'covariant' keyword, or removing the initializer.",
+        "Try removing either the 'final' or 'covariant' keyword, or removing "
+        "the initializer.",
   );
 
   static const ParserErrorCode FINAL_AND_VAR = ParserErrorCode(
@@ -815,7 +838,8 @@
 
   static const ParserErrorCode FUNCTION_TYPED_PARAMETER_VAR = ParserErrorCode(
     'FUNCTION_TYPED_PARAMETER_VAR',
-    "Function-typed parameters can't specify 'const', 'final' or 'var' in place of a return type.",
+    "Function-typed parameters can't specify 'const', 'final' or 'var' in "
+        "place of a return type.",
     correctionMessage: "Try replacing the keyword with a return type.",
   );
 
@@ -829,14 +853,16 @@
     'GETTER_IN_FUNCTION',
     "Getters can't be defined within methods or functions.",
     correctionMessage:
-        "Try moving the getter outside the method or function, or converting the getter to a function.",
+        "Try moving the getter outside the method or function, or converting "
+        "the getter to a function.",
   );
 
   static const ParserErrorCode GETTER_WITH_PARAMETERS = ParserErrorCode(
     'GETTER_WITH_PARAMETERS',
     "Getters must be declared without a parameter list.",
     correctionMessage:
-        "Try removing the parameter list, or removing the keyword 'get' to define a method rather than a getter.",
+        "Try removing the parameter list, or removing the keyword 'get' to "
+        "define a method rather than a getter.",
   );
 
   static const ParserErrorCode ILLEGAL_ASSIGNMENT_TO_NON_ASSIGNABLE =
@@ -898,7 +924,8 @@
 
   static const ParserErrorCode INVALID_COMMENT_REFERENCE = ParserErrorCode(
     'INVALID_COMMENT_REFERENCE',
-    "Comment references should contain a possibly prefixed identifier and can start with 'new', but shouldn't contain anything else.",
+    "Comment references should contain a possibly prefixed identifier and can "
+        "start with 'new', but shouldn't contain anything else.",
   );
 
   static const ParserErrorCode INVALID_CONSTRUCTOR_NAME = ParserErrorCode(
@@ -910,12 +937,14 @@
     'INVALID_GENERIC_FUNCTION_TYPE',
     "Invalid generic function type.",
     correctionMessage:
-        "Try using a generic function type (returnType 'Function(' parameters ')').",
+        "Try using a generic function type (returnType 'Function(' parameters "
+        "')').",
   );
 
   static const ParserErrorCode INVALID_HEX_ESCAPE = ParserErrorCode(
     'INVALID_HEX_ESCAPE',
-    "An escape sequence starting with '\\x' must be followed by 2 hexadecimal digits.",
+    "An escape sequence starting with '\\x' must be followed by 2 hexadecimal "
+        "digits.",
   );
 
   static const ParserErrorCode INVALID_INITIALIZER = ParserErrorCode(
@@ -955,7 +984,8 @@
   static const ParserErrorCode INVALID_OPERATOR_QUESTIONMARK_PERIOD_FOR_SUPER =
       ParserErrorCode(
     'INVALID_OPERATOR_QUESTIONMARK_PERIOD_FOR_SUPER',
-    "The operator '?.' cannot be used with 'super' because 'super' cannot be null.",
+    "The operator '?.' cannot be used with 'super' because 'super' cannot be "
+        "null.",
     correctionMessage: "Try replacing '?.' with '.'",
   );
 
@@ -967,7 +997,8 @@
 
   static const ParserErrorCode INVALID_SUPER_IN_INITIALIZER = ParserErrorCode(
     'INVALID_SUPER_IN_INITIALIZER',
-    "Can only use 'super' in an initializer for calling the superclass constructor (e.g. 'super()' or 'super.namedConstructor()')",
+    "Can only use 'super' in an initializer for calling the superclass "
+        "constructor (e.g. 'super()' or 'super.namedConstructor()')",
   );
 
   static const ParserErrorCode INVALID_SYNC = ParserErrorCode(
@@ -978,12 +1009,15 @@
 
   static const ParserErrorCode INVALID_THIS_IN_INITIALIZER = ParserErrorCode(
     'INVALID_THIS_IN_INITIALIZER',
-    "Can only use 'this' in an initializer for field initialization (e.g. 'this.x = something') and constructor redirection (e.g. 'this()' or 'this.namedConstructor())",
+    "Can only use 'this' in an initializer for field initialization (e.g. "
+        "'this.x = something') and constructor redirection (e.g. 'this()' or "
+        "'this.namedConstructor())",
   );
 
   static const ParserErrorCode INVALID_UNICODE_ESCAPE = ParserErrorCode(
     'INVALID_UNICODE_ESCAPE',
-    "An escape sequence starting with '\\u' must be followed by 4 hexadecimal digits or from 1 to 6 digits between '{' and '}'.",
+    "An escape sequence starting with '\\u' must be followed by 4 hexadecimal "
+        "digits or from 1 to 6 digits between '{' and '}'.",
   );
 
   /**
@@ -1079,7 +1113,8 @@
     'MISSING_CATCH_OR_FINALLY',
     "A try block must be followed by an 'on', 'catch', or 'finally' clause.",
     correctionMessage:
-        "Try adding either a catch or finally clause, or remove the try statement.",
+        "Try adding either a catch or finally clause, or remove the try "
+        "statement.",
   );
 
   static const ParserErrorCode MISSING_CLOSING_PARENTHESIS = ParserErrorCode(
@@ -1091,7 +1126,8 @@
   static const ParserErrorCode MISSING_CONST_FINAL_VAR_OR_TYPE =
       ParserErrorCode(
     'MISSING_CONST_FINAL_VAR_OR_TYPE',
-    "Variables must be declared using the keywords 'const', 'final', 'var' or a type name.",
+    "Variables must be declared using the keywords 'const', 'final', 'var' or "
+        "a type name.",
     correctionMessage:
         "Try adding the name of the type of the variable or the keyword 'var'.",
   );
@@ -1107,14 +1143,16 @@
     'MISSING_EXPRESSION_IN_INITIALIZER',
     "Expected an expression after the assignment operator.",
     correctionMessage:
-        "Try adding the value to be assigned, or remove the assignment operator.",
+        "Try adding the value to be assigned, or remove the assignment "
+        "operator.",
   );
 
   static const ParserErrorCode MISSING_EXPRESSION_IN_THROW = ParserErrorCode(
     'MISSING_EXPRESSION_IN_THROW',
     "Missing expression after 'throw'.",
     correctionMessage:
-        "Add an expression after 'throw' or use 'rethrow' to throw a caught exception",
+        "Add an expression after 'throw' or use 'rethrow' to throw a caught "
+        "exception",
   );
 
   static const ParserErrorCode MISSING_FUNCTION_BODY = ParserErrorCode(
@@ -1125,7 +1163,8 @@
 
   static const ParserErrorCode MISSING_FUNCTION_KEYWORD = ParserErrorCode(
     'MISSING_FUNCTION_KEYWORD',
-    "Function types must have the keyword 'Function' before the parameter list.",
+    "Function types must have the keyword 'Function' before the parameter "
+        "list.",
     correctionMessage: "Try adding the keyword 'Function'.",
   );
 
@@ -1176,7 +1215,8 @@
     'MISSING_NAME_IN_LIBRARY_DIRECTIVE',
     "Library directives must include a library name.",
     correctionMessage:
-        "Try adding a library name after the keyword 'library', or remove the library directive if the library doesn't have any parts.",
+        "Try adding a library name after the keyword 'library', or remove the "
+        "library directive if the library doesn't have any parts.",
   );
 
   static const ParserErrorCode MISSING_NAME_IN_PART_OF_DIRECTIVE =
@@ -1224,13 +1264,15 @@
 
   static const ParserErrorCode MISSING_VARIABLE_IN_FOR_EACH = ParserErrorCode(
     'MISSING_VARIABLE_IN_FOR_EACH',
-    "A loop variable must be declared in a for-each loop before the 'in', but none was found.",
+    "A loop variable must be declared in a for-each loop before the 'in', but "
+        "none was found.",
     correctionMessage: "Try declaring a loop variable.",
   );
 
   static const ParserErrorCode MIXED_PARAMETER_GROUPS = ParserErrorCode(
     'MIXED_PARAMETER_GROUPS',
-    "Can't have both positional and named parameters in a single parameter list.",
+    "Can't have both positional and named parameters in a single parameter "
+        "list.",
     correctionMessage: "Try choosing a single style of optional parameters.",
   );
 
@@ -1249,7 +1291,8 @@
     'MULTIPLE_EXTENDS_CLAUSES',
     "Each class definition can have at most one extends clause.",
     correctionMessage:
-        "Try choosing one superclass and define your class to implement (or mix in) the others.",
+        "Try choosing one superclass and define your class to implement (or "
+        "mix in) the others.",
   );
 
   static const ParserErrorCode MULTIPLE_IMPLEMENTS_CLAUSES = ParserErrorCode(
@@ -1268,7 +1311,8 @@
   static const ParserErrorCode MULTIPLE_NAMED_PARAMETER_GROUPS =
       ParserErrorCode(
     'MULTIPLE_NAMED_PARAMETER_GROUPS',
-    "Can't have multiple groups of named parameters in a single parameter list.",
+    "Can't have multiple groups of named parameters in a single parameter "
+        "list.",
     correctionMessage: "Try combining all of the groups into a single group.",
   );
 
@@ -1288,7 +1332,8 @@
   static const ParserErrorCode MULTIPLE_POSITIONAL_PARAMETER_GROUPS =
       ParserErrorCode(
     'MULTIPLE_POSITIONAL_PARAMETER_GROUPS',
-    "Can't have multiple groups of positional parameters in a single parameter list.",
+    "Can't have multiple groups of positional parameters in a single parameter "
+        "list.",
     correctionMessage: "Try combining all of the groups into a single group.",
   );
 
@@ -1298,7 +1343,8 @@
    */
   static const ParserErrorCode MULTIPLE_VARIABLES_IN_FOR_EACH = ParserErrorCode(
     'MULTIPLE_VARIABLES_IN_FOR_EACH',
-    "A single loop variable must be declared in a for-each loop before the 'in', but {0} were found.",
+    "A single loop variable must be declared in a for-each loop before the "
+        "'in', but {0} were found.",
     correctionMessage:
         "Try moving all but one of the declarations inside the loop body.",
   );
@@ -1321,7 +1367,8 @@
     'NAMED_FUNCTION_EXPRESSION',
     "Function expressions can't be named.",
     correctionMessage:
-        "Try removing the name, or moving the function expression to a function declaration statement.",
+        "Try removing the name, or moving the function expression to a "
+        "function declaration statement.",
   );
 
   static const ParserErrorCode NAMED_FUNCTION_TYPE = ParserErrorCode(
@@ -1338,7 +1385,8 @@
 
   static const ParserErrorCode NATIVE_CLAUSE_IN_NON_SDK_CODE = ParserErrorCode(
     'NATIVE_CLAUSE_IN_NON_SDK_CODE',
-    "Native clause can only be used in the SDK and code that is loaded through native extensions.",
+    "Native clause can only be used in the SDK and code that is loaded through "
+        "native extensions.",
     correctionMessage: "Try removing the native clause.",
   );
 
@@ -1347,13 +1395,15 @@
     'NATIVE_CLAUSE_SHOULD_BE_ANNOTATION',
     "Native clause in this form is deprecated.",
     correctionMessage:
-        "Try removing this native clause and adding @native() or @native('native-name') before the declaration.",
+        "Try removing this native clause and adding @native() or "
+        "@native('native-name') before the declaration.",
   );
 
   static const ParserErrorCode NATIVE_FUNCTION_BODY_IN_NON_SDK_CODE =
       ParserErrorCode(
     'NATIVE_FUNCTION_BODY_IN_NON_SDK_CODE',
-    "Native functions can only be declared in the SDK and code that is loaded through native extensions.",
+    "Native functions can only be declared in the SDK and code that is loaded "
+        "through native extensions.",
     correctionMessage: "Try removing the word 'native'.",
   );
 
@@ -1373,7 +1423,8 @@
     'NON_PART_OF_DIRECTIVE_IN_PART',
     "The part-of directive must be the only directive in a part.",
     correctionMessage:
-        "Try removing the other directives, or moving them to the library for which this is a part.",
+        "Try removing the other directives, or moving them to the library for "
+        "which this is a part.",
   );
 
   static const ParserErrorCode NON_STRING_LITERAL_AS_URI = ParserErrorCode(
@@ -1397,7 +1448,8 @@
     'NORMAL_BEFORE_OPTIONAL_PARAMETERS',
     "Normal parameters must occur before optional parameters.",
     correctionMessage:
-        "Try moving all of the normal parameters before the optional parameters.",
+        "Try moving all of the normal parameters before the optional "
+        "parameters.",
   );
 
   static const ParserErrorCode NULL_AWARE_CASCADE_OUT_OF_ORDER =
@@ -1405,7 +1457,8 @@
     'NULL_AWARE_CASCADE_OUT_OF_ORDER',
     "The '?..' cascade operator must be first in the cascade sequence.",
     correctionMessage:
-        "Try moving the '?..' operator to be the first cascade operator in the sequence.",
+        "Try moving the '?..' operator to be the first cascade operator in the "
+        "sequence.",
   );
 
   static const ParserErrorCode POSITIONAL_AFTER_NAMED_ARGUMENT =
@@ -1413,7 +1466,8 @@
     'POSITIONAL_AFTER_NAMED_ARGUMENT',
     "Positional arguments must occur before named arguments.",
     correctionMessage:
-        "Try moving all of the positional arguments before the named arguments.",
+        "Try moving all of the positional arguments before the named "
+        "arguments.",
   );
 
   static const ParserErrorCode POSITIONAL_PARAMETER_OUTSIDE_GROUP =
@@ -1515,7 +1569,8 @@
     'TOP_LEVEL_OPERATOR',
     "Operators must be declared within a class.",
     correctionMessage:
-        "Try removing the operator, moving it to a class, or converting it to be a function.",
+        "Try removing the operator, moving it to a class, or converting it to "
+        "be a function.",
   );
 
   static const ParserErrorCode TYPEDEF_IN_CLASS = ParserErrorCode(
@@ -1601,14 +1656,16 @@
     'VAR_RETURN_TYPE',
     "The return type can't be 'var'.",
     correctionMessage:
-        "Try removing the keyword 'var', or replacing it with the name of the return type.",
+        "Try removing the keyword 'var', or replacing it with the name of the "
+        "return type.",
   );
 
   static const ParserErrorCode VAR_TYPEDEF = ParserErrorCode(
     'VAR_TYPEDEF',
     "Typedefs can't be declared to be 'var'.",
     correctionMessage:
-        "Try removing the keyword 'var', or replacing it with the name of the return type.",
+        "Try removing the keyword 'var', or replacing it with the name of the "
+        "return type.",
   );
 
   static const ParserErrorCode VOID_WITH_TYPE_ARGUMENTS = ParserErrorCode(
diff --git a/pkg/analyzer/lib/src/dart/micro/library_analyzer.dart b/pkg/analyzer/lib/src/dart/micro/library_analyzer.dart
index 0b096be..d3ba759 100644
--- a/pkg/analyzer/lib/src/dart/micro/library_analyzer.dart
+++ b/pkg/analyzer/lib/src/dart/micro/library_analyzer.dart
@@ -362,18 +362,15 @@
   }
 
   void _computeVerifyErrors(FileState file, CompilationUnit unit) {
-    RecordingErrorListener errorListener = _getErrorListener(file);
+    ErrorReporter errorReporter = _getErrorReporter(file);
 
     CodeChecker checker = CodeChecker(
       _typeProvider,
       _typeSystem,
-      _inheritance,
-      errorListener,
+      errorReporter,
     );
     checker.visitCompilationUnit(unit);
 
-    ErrorReporter errorReporter = _getErrorReporter(file);
-
     //
     // Validate the directives.
     //
diff --git a/pkg/analyzer/lib/src/dart/micro/library_graph.dart b/pkg/analyzer/lib/src/dart/micro/library_graph.dart
index 80357fb..6476871 100644
--- a/pkg/analyzer/lib/src/dart/micro/library_graph.dart
+++ b/pkg/analyzer/lib/src/dart/micro/library_graph.dart
@@ -43,39 +43,9 @@
   libraryWalker.walk(libraryWalker.getNode(file));
 }
 
-class CiderUnitTopLevelDeclarations {
-  final List<String> extensionNames;
-  final List<String> functionNames;
-  final List<String> typeNames;
-  final List<String> variableNames;
-
-  CiderUnitTopLevelDeclarations({
-    required this.extensionNames,
-    required this.functionNames,
-    required this.typeNames,
-    required this.variableNames,
-  });
-
-  factory CiderUnitTopLevelDeclarations.read(SummaryDataReader reader) {
-    return CiderUnitTopLevelDeclarations(
-      extensionNames: reader.readStringUtf8List(),
-      functionNames: reader.readStringUtf8List(),
-      typeNames: reader.readStringUtf8List(),
-      variableNames: reader.readStringUtf8List(),
-    );
-  }
-
-  void write(BufferedSink sink) {
-    sink.writeStringUtf8Iterable(extensionNames);
-    sink.writeStringUtf8Iterable(functionNames);
-    sink.writeStringUtf8Iterable(typeNames);
-    sink.writeStringUtf8Iterable(variableNames);
-  }
-}
-
 class CiderUnlinkedUnit {
   /// Top-level declarations of the unit.
-  final CiderUnitTopLevelDeclarations topLevelDeclarations;
+  final Set<String> topLevelDeclarations;
 
   /// Unlinked summary of the compilation unit.
   final UnlinkedUnit unit;
@@ -93,7 +63,7 @@
 
   factory CiderUnlinkedUnit.read(SummaryDataReader reader) {
     return CiderUnlinkedUnit(
-      topLevelDeclarations: CiderUnitTopLevelDeclarations.read(reader),
+      topLevelDeclarations: reader.readStringUtf8Set(),
       unit: UnlinkedUnit.read(reader),
     );
   }
@@ -106,7 +76,7 @@
   }
 
   void write(BufferedSink sink) {
-    topLevelDeclarations.write(sink);
+    sink.writeStringUtf8Iterable(topLevelDeclarations);
     unit.write(sink);
   }
 }
@@ -386,40 +356,12 @@
   }
 
   /// Return files that have a top-level declaration with the [name].
-  List<FileWithTopLevelDeclaration> getFilesWithTopLevelDeclarations(
-    String name,
-  ) {
-    var result = <FileWithTopLevelDeclaration>[];
-
+  List<FileState> getFilesWithTopLevelDeclarations(String name) {
+    var result = <FileState>[];
     for (var file in _pathToFile.values) {
-      void addDeclaration(
-        List<String> names,
-        FileTopLevelDeclarationKind kind,
-      ) {
-        if (names.contains(name)) {
-          result.add(
-            FileWithTopLevelDeclaration(file: file, kind: kind),
-          );
-        }
+      if (file._unlinked.unlinked.topLevelDeclarations.contains(name)) {
+        result.add(file);
       }
-
-      var topLevelDeclarations = file._unlinked.unlinked.topLevelDeclarations;
-      addDeclaration(
-        topLevelDeclarations.extensionNames,
-        FileTopLevelDeclarationKind.extension,
-      );
-      addDeclaration(
-        topLevelDeclarations.functionNames,
-        FileTopLevelDeclarationKind.function,
-      );
-      addDeclaration(
-        topLevelDeclarations.typeNames,
-        FileTopLevelDeclarationKind.type,
-      );
-      addDeclaration(
-        topLevelDeclarations.variableNames,
-        FileTopLevelDeclarationKind.variable,
-      );
     }
     return result;
   }
@@ -527,20 +469,6 @@
   }
 }
 
-/// The kind in [FileWithTopLevelDeclaration].
-enum FileTopLevelDeclarationKind { extension, function, type, variable }
-
-/// The data structure for top-level declarations response.
-class FileWithTopLevelDeclaration {
-  final FileState file;
-  final FileTopLevelDeclarationKind kind;
-
-  FileWithTopLevelDeclaration({
-    required this.file,
-    required this.kind,
-  });
-}
-
 /// Information about libraries that reference each other, so form a cycle.
 class LibraryCycle {
   /// The libraries that belong to this cycle.
@@ -1004,27 +932,24 @@
       );
     }
 
-    var declaredExtensions = <String>[];
-    var declaredFunctions = <String>[];
-    var declaredTypes = <String>[];
-    var declaredVariables = <String>[];
+    var topLevelDeclarations = <String>{};
     for (var declaration in unit.declarations) {
       if (declaration is ClassDeclaration) {
-        declaredTypes.add(declaration.name.name);
+        topLevelDeclarations.add(declaration.name.name);
       } else if (declaration is EnumDeclaration) {
-        declaredTypes.add(declaration.name.name);
+        topLevelDeclarations.add(declaration.name.name);
       } else if (declaration is ExtensionDeclaration) {
         var name = declaration.name;
         if (name != null) {
-          declaredExtensions.add(name.name);
+          topLevelDeclarations.add(name.name);
         }
       } else if (declaration is FunctionDeclaration) {
-        declaredFunctions.add(declaration.name.name);
+        topLevelDeclarations.add(declaration.name.name);
       } else if (declaration is MixinDeclaration) {
-        declaredTypes.add(declaration.name.name);
+        topLevelDeclarations.add(declaration.name.name);
       } else if (declaration is TopLevelVariableDeclaration) {
         for (var variable in declaration.variables.variables) {
-          declaredVariables.add(variable.name.name);
+          topLevelDeclarations.add(variable.name.name);
         }
       }
     }
@@ -1044,12 +969,7 @@
 
     return CiderUnlinkedUnit(
       unit: unlinkedUnit,
-      topLevelDeclarations: CiderUnitTopLevelDeclarations(
-        extensionNames: declaredExtensions,
-        functionNames: declaredFunctions,
-        typeNames: declaredTypes,
-        variableNames: declaredVariables,
-      ),
+      topLevelDeclarations: topLevelDeclarations,
     );
   }
 
diff --git a/pkg/analyzer/lib/src/dart/micro/resolve_file.dart b/pkg/analyzer/lib/src/dart/micro/resolve_file.dart
index e9eec90..ac5a4809 100644
--- a/pkg/analyzer/lib/src/dart/micro/resolve_file.dart
+++ b/pkg/analyzer/lib/src/dart/micro/resolve_file.dart
@@ -310,9 +310,7 @@
   }
 
   /// Return files that have a top-level declaration with the [name].
-  List<FileWithTopLevelDeclaration> getFilesWithTopLevelDeclarations(
-    String name,
-  ) {
+  List<FileState> getFilesWithTopLevelDeclarations(String name) {
     final fsState = this.fsState;
     if (fsState == null) {
       return const [];
@@ -569,7 +567,7 @@
 
       var libraryUnit = resolvedUnits.first;
       var result = ResolvedLibraryResultImpl(contextObjects!.analysisSession,
-          path, libraryUnit.uri, libraryUnit.libraryElement, resolvedUnits);
+          libraryUnit.libraryElement, resolvedUnits);
 
       if (completionPath == null) {
         cachedResults[path] = result;
diff --git a/pkg/analyzer/lib/src/dart/resolver/applicable_extensions.dart b/pkg/analyzer/lib/src/dart/resolver/applicable_extensions.dart
new file mode 100644
index 0000000..5d26817
--- /dev/null
+++ b/pkg/analyzer/lib/src/dart/resolver/applicable_extensions.dart
@@ -0,0 +1,236 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analyzer/dart/analysis/features.dart';
+import 'package:analyzer/dart/element/element.dart';
+import 'package:analyzer/dart/element/type.dart';
+import 'package:analyzer/src/dart/element/element.dart';
+import 'package:analyzer/src/dart/element/generic_inferrer.dart';
+import 'package:analyzer/src/dart/element/member.dart';
+import 'package:analyzer/src/dart/element/type.dart';
+import 'package:analyzer/src/dart/element/type_algebra.dart';
+import 'package:analyzer/src/dart/resolver/resolution_result.dart';
+
+class InstantiatedExtensionWithMember {
+  final _NotInstantiatedExtensionWithMember candidate;
+  final MapSubstitution substitution;
+  final DartType extendedType;
+
+  InstantiatedExtensionWithMember(
+    this.candidate,
+    this.substitution,
+    this.extendedType,
+  );
+
+  ResolutionResult get asResolutionResult {
+    return ResolutionResult(getter: getter, setter: setter);
+  }
+
+  ExtensionElement get extension => candidate.extension;
+
+  ExecutableElement? get getter {
+    var getter = candidate.getter;
+    if (getter == null) {
+      return null;
+    }
+    return ExecutableMember.from2(getter, substitution);
+  }
+
+  ExecutableElement? get setter {
+    var setter = candidate.setter;
+    if (setter == null) {
+      return null;
+    }
+    return ExecutableMember.from2(setter, substitution);
+  }
+}
+
+class InstantiatedExtensionWithoutMember {
+  final ExtensionElement extension;
+  final MapSubstitution substitution;
+  final DartType extendedType;
+
+  InstantiatedExtensionWithoutMember(
+    this.extension,
+    this.substitution,
+    this.extendedType,
+  );
+}
+
+abstract class _NotInstantiatedExtension<R> {
+  final ExtensionElement extension;
+
+  _NotInstantiatedExtension(this.extension);
+
+  R instantiate({
+    required MapSubstitution substitution,
+    required DartType extendedType,
+  });
+}
+
+class _NotInstantiatedExtensionWithMember
+    extends _NotInstantiatedExtension<InstantiatedExtensionWithMember> {
+  final ExecutableElement? getter;
+  final ExecutableElement? setter;
+
+  _NotInstantiatedExtensionWithMember(ExtensionElement extension,
+      {this.getter, this.setter})
+      : assert(getter != null || setter != null),
+        super(extension);
+
+  @override
+  InstantiatedExtensionWithMember instantiate({
+    required MapSubstitution substitution,
+    required DartType extendedType,
+  }) {
+    return InstantiatedExtensionWithMember(this, substitution, extendedType);
+  }
+}
+
+/// [_NotInstantiatedExtension] for any [ExtensionElement].
+class _NotInstantiatedExtensionWithoutMember
+    extends _NotInstantiatedExtension<InstantiatedExtensionWithoutMember> {
+  _NotInstantiatedExtensionWithoutMember(ExtensionElement extension)
+      : super(extension);
+
+  @override
+  InstantiatedExtensionWithoutMember instantiate({
+    required MapSubstitution substitution,
+    required DartType extendedType,
+  }) {
+    return InstantiatedExtensionWithoutMember(
+        extension, substitution, extendedType);
+  }
+}
+
+extension ExtensionsExtensions on Iterable<ExtensionElement> {
+  /// Extensions that can be applied, within [targetLibrary], to [targetType].
+  List<InstantiatedExtensionWithoutMember> applicableTo({
+    required LibraryElement targetLibrary,
+    required DartType targetType,
+  }) {
+    return map((e) => _NotInstantiatedExtensionWithoutMember(e)).applicableTo(
+      targetLibrary: targetLibrary,
+      targetType: targetType,
+    );
+  }
+
+  List<_NotInstantiatedExtensionWithMember> hasMemberWithBaseName(
+    String baseName,
+  ) {
+    var result = <_NotInstantiatedExtensionWithMember>[];
+    for (var extension in this) {
+      if (baseName == '[]') {
+        ExecutableElement? getter;
+        ExecutableElement? setter;
+        for (var method in extension.methods) {
+          if (method.name == '[]') {
+            getter = method;
+          } else if (method.name == '[]=') {
+            setter = method;
+          }
+        }
+        if (getter != null || setter != null) {
+          result.add(
+            _NotInstantiatedExtensionWithMember(
+              extension,
+              getter: getter,
+              setter: setter,
+            ),
+          );
+        }
+      } else {
+        for (var field in extension.fields) {
+          if (field.name == baseName) {
+            result.add(
+              _NotInstantiatedExtensionWithMember(
+                extension,
+                getter: field.getter,
+                setter: field.setter,
+              ),
+            );
+            break;
+          }
+        }
+        for (var method in extension.methods) {
+          if (method.name == baseName) {
+            result.add(
+              _NotInstantiatedExtensionWithMember(
+                extension,
+                getter: method,
+              ),
+            );
+            break;
+          }
+        }
+      }
+    }
+    return result;
+  }
+}
+
+extension NotInstantiatedExtensionsExtensions<R>
+    on Iterable<_NotInstantiatedExtension<R>> {
+  /// Extensions that can be applied, within [targetLibrary], to [targetType].
+  List<R> applicableTo({
+    required LibraryElement targetLibrary,
+    required DartType targetType,
+  }) {
+    if (identical(targetType, NeverTypeImpl.instance)) {
+      return <R>[];
+    }
+
+    targetLibrary as LibraryElementImpl;
+    var typeSystem = targetLibrary.typeSystem;
+    var genericMetadataIsEnabled = targetLibrary.featureSet.isEnabled(
+      Feature.generic_metadata,
+    );
+
+    var instantiated = <R>[];
+
+    for (var notInstantiated in this) {
+      var extension = notInstantiated.extension;
+
+      var freshTypes = getFreshTypeParameters(extension.typeParameters);
+      var freshTypeParameters = freshTypes.freshTypeParameters;
+      var rawExtendedType = freshTypes.substitute(extension.extendedType);
+
+      var inferrer = GenericInferrer(typeSystem, freshTypeParameters);
+      inferrer.constrainArgument(
+        targetType,
+        rawExtendedType,
+        'extendedType',
+      );
+      var typeArguments = inferrer.infer(
+        freshTypeParameters,
+        failAtError: true,
+        genericMetadataIsEnabled: genericMetadataIsEnabled,
+      );
+      if (typeArguments == null) {
+        continue;
+      }
+
+      var substitution = Substitution.fromPairs(
+        extension.typeParameters,
+        typeArguments,
+      );
+      var extendedType = substitution.substituteType(
+        extension.extendedType,
+      );
+
+      if (!typeSystem.isSubtypeOf(targetType, extendedType)) {
+        continue;
+      }
+
+      instantiated.add(
+        notInstantiated.instantiate(
+          substitution: substitution,
+          extendedType: extendedType,
+        ),
+      );
+    }
+
+    return instantiated;
+  }
+}
diff --git a/pkg/analyzer/lib/src/dart/resolver/ast_rewrite.dart b/pkg/analyzer/lib/src/dart/resolver/ast_rewrite.dart
index 25dfe1a..61f364e 100644
--- a/pkg/analyzer/lib/src/dart/resolver/ast_rewrite.dart
+++ b/pkg/analyzer/lib/src/dart/resolver/ast_rewrite.dart
@@ -232,7 +232,7 @@
       return node;
     }
     if (parent is CommentReference) {
-      // TODO(srawlins): This probably should be rewritten to a
+      // TODO(srawlins): This probably should be allowed to be rewritten to a
       // [ConstructorReference] at some point.
       return node;
     }
@@ -281,6 +281,11 @@
       // `Type`.
       return node;
     }
+    if (node.parent is CommentReference) {
+      // TODO(srawlins): This probably should be allowed to be rewritten to a
+      // [ConstructorReference] at some point.
+      return node;
+    }
     var receiver = node.target!;
 
     Identifier receiverIdentifier;
diff --git a/pkg/analyzer/lib/src/dart/resolver/comment_reference_resolver.dart b/pkg/analyzer/lib/src/dart/resolver/comment_reference_resolver.dart
new file mode 100644
index 0000000..e67b6b1
--- /dev/null
+++ b/pkg/analyzer/lib/src/dart/resolver/comment_reference_resolver.dart
@@ -0,0 +1,192 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/element/element.dart';
+import 'package:analyzer/dart/element/type.dart';
+import 'package:analyzer/src/dart/ast/ast.dart';
+import 'package:analyzer/src/dart/element/type_provider.dart';
+import 'package:analyzer/src/dart/resolver/type_property_resolver.dart';
+import 'package:analyzer/src/generated/resolver.dart';
+
+class CommentReferenceResolver {
+  final TypeProviderImpl _typeProvider;
+
+  final ResolverVisitor _resolver;
+
+  /// Helper for resolving properties on types.
+  final TypePropertyResolver _typePropertyResolver;
+
+  CommentReferenceResolver(this._typeProvider, this._resolver)
+      : _typePropertyResolver = _resolver.typePropertyResolver;
+
+  /// Resolves [commentReference].
+  void resolve(CommentReference commentReference) {
+    var expression = commentReference.expression;
+    if (expression is SimpleIdentifierImpl) {
+      _resolveSimpleIdentifierReference(expression,
+          hasNewKeyword: commentReference.newKeyword != null);
+    } else if (expression is PrefixedIdentifierImpl) {
+      _resolvePrefixedIdentifierReference(expression,
+          hasNewKeyword: commentReference.newKeyword != null);
+    } else if (expression is PropertyAccessImpl) {
+      _resolvePropertyAccessReference(expression,
+          hasNewKeyword: commentReference.newKeyword != null);
+    }
+  }
+
+  void _resolvePrefixedIdentifierReference(
+    PrefixedIdentifierImpl expression, {
+    required bool hasNewKeyword,
+  }) {
+    var prefix = expression.prefix;
+    var prefixElement = _resolveSimpleIdentifier(prefix);
+    prefix.staticElement = prefixElement;
+
+    if (prefixElement == null) {
+      return;
+    }
+
+    var name = expression.identifier;
+
+    if (prefixElement is PrefixElement) {
+      var prefixScope = prefixElement.scope;
+      var lookupResult = prefixScope.lookup(name.name);
+      var element = lookupResult.getter ?? lookupResult.setter;
+      element = _resolver.toLegacyElement(element);
+      name.staticElement = element;
+      return;
+    }
+
+    if (!hasNewKeyword) {
+      if (prefixElement is ClassElement) {
+        name.staticElement = prefixElement.getMethod(name.name) ??
+            prefixElement.getGetter(name.name) ??
+            prefixElement.getSetter(name.name) ??
+            prefixElement.getNamedConstructor(name.name);
+      } else if (prefixElement is ExtensionElement) {
+        name.staticElement = prefixElement.getMethod(name.name) ??
+            prefixElement.getGetter(name.name) ??
+            prefixElement.getSetter(name.name);
+      } else {
+        // TODO(brianwilkerson) Report this error.
+      }
+    } else if (prefixElement is ClassElement) {
+      var constructor = prefixElement.getNamedConstructor(name.name);
+      if (constructor == null) {
+        // TODO(brianwilkerson) Report this error.
+      } else {
+        name.staticElement = constructor;
+      }
+    } else {
+      // TODO(brianwilkerson) Report this error.
+    }
+  }
+
+  void _resolvePropertyAccessReference(
+    PropertyAccessImpl expression, {
+    required bool hasNewKeyword,
+  }) {
+    var target = expression.target;
+    if (target is! PrefixedIdentifierImpl) {
+      // A PropertyAccess with a target more complex than a
+      // [PrefixedIdentifier] is not a valid comment reference.
+      return;
+    }
+
+    var prefix = target.prefix;
+    var prefixElement = _resolveSimpleIdentifier(prefix);
+    prefix.staticElement = prefixElement;
+
+    if (prefixElement is! PrefixElement) {
+      // The only valid prefixElement is a PrefixElement; otherwise, this is
+      // not a comment reference.
+      return;
+    }
+
+    var name = target.identifier;
+    var prefixScope = prefixElement.scope;
+    var lookupResult = prefixScope.lookup(name.name);
+    var element = lookupResult.getter ?? lookupResult.setter;
+    element = _resolver.toLegacyElement(element);
+    name.staticElement = element;
+
+    var propertyName = expression.propertyName;
+    if (element is ClassElement) {
+      propertyName.staticElement = element.getMethod(propertyName.name) ??
+          element.getGetter(propertyName.name) ??
+          element.getSetter(propertyName.name) ??
+          element.getNamedConstructor(propertyName.name);
+    } else if (element is ExtensionElement) {
+      propertyName.staticElement = element.getMethod(propertyName.name) ??
+          element.getGetter(propertyName.name) ??
+          element.getSetter(propertyName.name);
+    }
+  }
+
+  /// Resolves the given simple [identifier] if possible.
+  ///
+  /// Returns the resolved element, or `null` if the identifier could not be
+  /// resolved. This does not record the results of the resolution.
+  Element? _resolveSimpleIdentifier(SimpleIdentifierImpl identifier) {
+    var lookupResult = identifier.scopeLookupResult!;
+
+    var element = _resolver.toLegacyElement(lookupResult.getter) ??
+        _resolver.toLegacyElement(lookupResult.setter);
+
+    if (element == null) {
+      InterfaceType enclosingType;
+      var enclosingClass = _resolver.enclosingClass;
+      if (enclosingClass != null) {
+        enclosingType = enclosingClass.thisType;
+      } else {
+        var enclosingExtension = _resolver.enclosingExtension;
+        if (enclosingExtension == null) {
+          return null;
+        }
+        var extendedType = enclosingExtension.extendedType
+            .resolveToBound(_typeProvider.objectType);
+        if (extendedType is InterfaceType) {
+          enclosingType = extendedType;
+        } else if (extendedType is FunctionType) {
+          enclosingType = _typeProvider.functionType;
+        } else {
+          return null;
+        }
+      }
+      var result = _typePropertyResolver.resolve(
+        receiver: null,
+        receiverType: enclosingType,
+        name: identifier.name,
+        propertyErrorEntity: identifier,
+        nameErrorEntity: identifier,
+      );
+      element = result.getter ?? result.setter;
+    }
+    return element;
+  }
+
+  void _resolveSimpleIdentifierReference(
+    SimpleIdentifierImpl expression, {
+    required bool hasNewKeyword,
+  }) {
+    var element = _resolveSimpleIdentifier(expression);
+    if (element == null) {
+      return;
+    }
+    expression.staticElement = element;
+    if (hasNewKeyword) {
+      if (element is ClassElement) {
+        var constructor = element.unnamedConstructor;
+        if (constructor == null) {
+          // TODO(brianwilkerson) Report this error.
+        } else {
+          expression.staticElement = constructor;
+        }
+      } else {
+        // TODO(brianwilkerson) Report this error.
+      }
+    }
+  }
+}
diff --git a/pkg/analyzer/lib/src/dart/resolver/extension_member_resolver.dart b/pkg/analyzer/lib/src/dart/resolver/extension_member_resolver.dart
index c7afae0..517ff5c 100644
--- a/pkg/analyzer/lib/src/dart/resolver/extension_member_resolver.dart
+++ b/pkg/analyzer/lib/src/dart/resolver/extension_member_resolver.dart
@@ -13,10 +13,10 @@
 import 'package:analyzer/src/dart/ast/extensions.dart';
 import 'package:analyzer/src/dart/element/generic_inferrer.dart';
 import 'package:analyzer/src/dart/element/member.dart';
-import 'package:analyzer/src/dart/element/type.dart';
 import 'package:analyzer/src/dart/element/type_algebra.dart';
 import 'package:analyzer/src/dart/element/type_schema.dart';
 import 'package:analyzer/src/dart/element/type_system.dart';
+import 'package:analyzer/src/dart/resolver/applicable_extensions.dart';
 import 'package:analyzer/src/dart/resolver/resolution_result.dart';
 import 'package:analyzer/src/error/codes.dart';
 import 'package:analyzer/src/generated/resolver.dart';
@@ -54,7 +54,12 @@
     SyntacticEntity nameEntity,
     String name,
   ) {
-    var extensions = _getApplicable(type, name);
+    var extensions = _resolver.definingLibrary.accessibleExtensions
+        .hasMemberWithBaseName(name)
+        .applicableTo(
+          targetLibrary: _resolver.definingLibrary,
+          targetType: type,
+        );
 
     if (extensions.isEmpty) {
       return ResolutionResult.none;
@@ -263,10 +268,11 @@
 
   /// Return either the most specific extension, or a list of the extensions
   /// that are ambiguous.
-  Either2<_InstantiatedExtension, List<_InstantiatedExtension>>
-      _chooseMostSpecific(List<_InstantiatedExtension> extensions) {
-    _InstantiatedExtension? bestSoFar;
-    var noneMoreSpecific = <_InstantiatedExtension>[];
+  Either2<InstantiatedExtensionWithMember,
+          List<InstantiatedExtensionWithMember>>
+      _chooseMostSpecific(List<InstantiatedExtensionWithMember> extensions) {
+    InstantiatedExtensionWithMember? bestSoFar;
+    var noneMoreSpecific = <InstantiatedExtensionWithMember>[];
     for (var candidate in extensions) {
       if (noneMoreSpecific.isNotEmpty) {
         var isMostSpecific = true;
@@ -305,110 +311,6 @@
     }
   }
 
-  /// Return extensions for the [type] that match the given [name] in the
-  /// current scope.
-  List<_InstantiatedExtension> _getApplicable(DartType type, String name) {
-    if (identical(type, NeverTypeImpl.instance)) {
-      return const <_InstantiatedExtension>[];
-    }
-
-    var candidates = _getExtensionsWithMember(name);
-
-    var instantiatedExtensions = <_InstantiatedExtension>[];
-    for (var candidate in candidates) {
-      var extension = candidate.extension;
-
-      var freshTypes = getFreshTypeParameters(extension.typeParameters);
-      var freshTypeParameters = freshTypes.freshTypeParameters;
-      var rawExtendedType = freshTypes.substitute(extension.extendedType);
-
-      var inferrer = GenericInferrer(_typeSystem, freshTypeParameters);
-      inferrer.constrainArgument(
-        type,
-        rawExtendedType,
-        'extendedType',
-      );
-      var typeArguments = inferrer.infer(
-        freshTypeParameters,
-        failAtError: true,
-        genericMetadataIsEnabled: _genericMetadataIsEnabled,
-      );
-      if (typeArguments == null) {
-        continue;
-      }
-
-      var substitution = Substitution.fromPairs(
-        extension.typeParameters,
-        typeArguments,
-      );
-      var extendedType = substitution.substituteType(
-        extension.extendedType,
-      );
-      if (!_isSubtypeOf(type, extendedType)) {
-        continue;
-      }
-
-      instantiatedExtensions.add(
-        _InstantiatedExtension(candidate, substitution, extendedType),
-      );
-    }
-
-    return instantiatedExtensions;
-  }
-
-  /// Return extensions from the current scope, that define a member with the
-  /// given [name].
-  List<_CandidateExtension> _getExtensionsWithMember(String name) {
-    var candidates = <_CandidateExtension>[];
-
-    /// Add the given [extension] to the list of [candidates] if it defined a
-    /// member whose name matches the target [name].
-    void checkExtension(ExtensionElement extension) {
-      for (var field in extension.fields) {
-        if (field.name == name) {
-          candidates.add(
-            _CandidateExtension(
-              extension,
-              getter: field.getter,
-              setter: field.setter,
-            ),
-          );
-          return;
-        }
-      }
-      if (name == '[]') {
-        ExecutableElement? getter;
-        ExecutableElement? setter;
-        for (var method in extension.methods) {
-          if (method.name == '[]') {
-            getter = method;
-          } else if (method.name == '[]=') {
-            setter = method;
-          }
-        }
-        if (getter != null || setter != null) {
-          candidates.add(
-            _CandidateExtension(extension, getter: getter, setter: setter),
-          );
-        }
-      } else {
-        for (var method in extension.methods) {
-          if (method.name == name) {
-            candidates.add(
-              _CandidateExtension(extension, getter: method),
-            );
-            return;
-          }
-        }
-      }
-    }
-
-    for (var extension in _resolver.definingLibrary.accessibleExtensions) {
-      checkExtension(extension);
-    }
-    return candidates;
-  }
-
   /// Given the generic [element] element, either return types specified
   /// explicitly in [typeArguments], or infer type arguments from the given
   /// [receiverType].
@@ -469,7 +371,8 @@
   }
 
   /// Return `true` is [e1] is more specific than [e2].
-  bool _isMoreSpecific(_InstantiatedExtension e1, _InstantiatedExtension e2) {
+  bool _isMoreSpecific(
+      InstantiatedExtensionWithMember e1, InstantiatedExtensionWithMember e2) {
     // 1. The latter extension is declared in a platform library, and the
     //    former extension is not.
     // 2. They are both declared in platform libraries, or both declared in
@@ -531,42 +434,3 @@
         parent is PropertyAccess && parent.target == node;
   }
 }
-
-class _CandidateExtension {
-  final ExtensionElement extension;
-  final ExecutableElement? getter;
-  final ExecutableElement? setter;
-
-  _CandidateExtension(this.extension, {this.getter, this.setter})
-      : assert(getter != null || setter != null);
-}
-
-class _InstantiatedExtension {
-  final _CandidateExtension candidate;
-  final MapSubstitution substitution;
-  final DartType extendedType;
-
-  _InstantiatedExtension(this.candidate, this.substitution, this.extendedType);
-
-  ResolutionResult get asResolutionResult {
-    return ResolutionResult(getter: getter, setter: setter);
-  }
-
-  ExtensionElement get extension => candidate.extension;
-
-  ExecutableElement? get getter {
-    var getter = candidate.getter;
-    if (getter == null) {
-      return null;
-    }
-    return ExecutableMember.from2(getter, substitution);
-  }
-
-  ExecutableElement? get setter {
-    var setter = candidate.setter;
-    if (setter == null) {
-      return null;
-    }
-    return ExecutableMember.from2(setter, substitution);
-  }
-}
diff --git a/pkg/analyzer/lib/src/dart/resolver/function_expression_resolver.dart b/pkg/analyzer/lib/src/dart/resolver/function_expression_resolver.dart
index be1eec6..2558708 100644
--- a/pkg/analyzer/lib/src/dart/resolver/function_expression_resolver.dart
+++ b/pkg/analyzer/lib/src/dart/resolver/function_expression_resolver.dart
@@ -9,7 +9,6 @@
 import 'package:analyzer/src/dart/element/element.dart';
 import 'package:analyzer/src/dart/element/type.dart';
 import 'package:analyzer/src/dart/element/type_system.dart';
-import 'package:analyzer/src/dart/resolver/body_inference_context.dart';
 import 'package:analyzer/src/dart/resolver/invocation_inference_helper.dart';
 import 'package:analyzer/src/generated/migration.dart';
 import 'package:analyzer/src/generated/resolver.dart';
@@ -64,9 +63,7 @@
     _resolve2(node);
 
     if (_resolver.flowAnalysis.flow != null && !isFunctionDeclaration) {
-      var bodyContext = BodyInferenceContext.of(node.body);
       _resolver.checkForBodyMayCompleteNormally(
-        returnType: bodyContext?.contextType,
         body: body,
         errorNode: body,
       );
diff --git a/pkg/analyzer/lib/src/dart/resolver/resolution_visitor.dart b/pkg/analyzer/lib/src/dart/resolver/resolution_visitor.dart
index 2e361ad..8138fda 100644
--- a/pkg/analyzer/lib/src/dart/resolver/resolution_visitor.dart
+++ b/pkg/analyzer/lib/src/dart/resolver/resolution_visitor.dart
@@ -976,6 +976,57 @@
   }
 
   @override
+  void visitSuperFormalParameter(covariant SuperFormalParameterImpl node) {
+    SuperFormalParameterElementImpl element;
+    if (node.parent is DefaultFormalParameter) {
+      element = node.declaredElement as SuperFormalParameterElementImpl;
+    } else {
+      var nameNode = node.identifier;
+      if (_elementWalker != null) {
+        element =
+            _elementWalker!.getParameter() as SuperFormalParameterElementImpl;
+      } else {
+        // Only for recovery, this should not happen in valid code.
+        element = SuperFormalParameterElementImpl(
+          name: nameNode.name,
+          nameOffset: nameNode.offset,
+          parameterKind: node.kind,
+        );
+        _elementHolder.enclose(element);
+        element.isConst = node.isConst;
+        element.isExplicitlyCovariant = node.covariantKeyword != null;
+        element.isFinal = node.isFinal;
+        _setCodeRange(element, node);
+      }
+      nameNode.staticElement = element;
+    }
+
+    _setOrCreateMetadataElements(element, node.metadata);
+
+    _withElementHolder(ElementHolder(element), () {
+      _withElementWalker(
+        _elementWalker != null ? ElementWalker.forParameter(element) : null,
+        () {
+          _withNameScope(() {
+            _buildTypeParameterElements(node.typeParameters);
+            node.typeParameters?.accept(this);
+            node.type?.accept(this);
+            if (_elementWalker != null) {
+              node.parameters?.accept(this);
+            } else {
+              // Only for recovery, this should not happen in valid code.
+              element.type = node.type?.type ?? _dynamicType;
+              _withElementWalker(null, () {
+                node.parameters?.accept(this);
+              });
+            }
+          });
+        },
+      );
+    });
+  }
+
+  @override
   void visitSwitchCase(SwitchCase node) {
     _buildLabelElements(node.labels, false, true);
 
diff --git a/pkg/analyzer/lib/src/error/codes.g.dart b/pkg/analyzer/lib/src/error/codes.g.dart
index be02c3e4..42f8ae1 100644
--- a/pkg/analyzer/lib/src/error/codes.g.dart
+++ b/pkg/analyzer/lib/src/error/codes.g.dart
@@ -67,7 +67,8 @@
     'ABSTRACT_FIELD_INITIALIZER',
     "Abstract fields can't have initializers.",
     correctionMessage:
-        "Try removing the field initializer or the 'abstract' keyword from the field declaration.",
+        "Try removing the field initializer or the 'abstract' keyword from the "
+        "field declaration.",
     hasPublishedDocs: true,
     uniqueName: 'ABSTRACT_FIELD_CONSTRUCTOR_INITIALIZER',
   );
@@ -177,7 +178,8 @@
     'AMBIGUOUS_EXPORT',
     "The name '{0}' is defined in the libraries '{1}' and '{2}'.",
     correctionMessage:
-        "Try removing the export of one of the libraries, or explicitly hiding the name in one of the export directives.",
+        "Try removing the export of one of the libraries, or explicitly hiding "
+        "the name in one of the export directives.",
     hasPublishedDocs: true,
   );
 
@@ -245,7 +247,8 @@
     'AMBIGUOUS_EXTENSION_MEMBER_ACCESS',
     "A member named '{0}' is defined in {1}, and none are more specific.",
     correctionMessage:
-        "Try using an extension override to specify the extension you want to be chosen.",
+        "Try using an extension override to specify the extension you want to "
+        "be chosen.",
     hasPublishedDocs: true,
   );
 
@@ -322,7 +325,8 @@
     'AMBIGUOUS_IMPORT',
     "The name '{0}' is defined in the libraries {1}.",
     correctionMessage:
-        "Try using 'as prefix' for one of the import directives, or hiding the name from all but one of the imports.",
+        "Try using 'as prefix' for one of the import directives, or hiding the "
+        "name from all but one of the imports.",
     hasPublishedDocs: true,
   );
 
@@ -380,9 +384,12 @@
   static const CompileTimeErrorCode AMBIGUOUS_SET_OR_MAP_LITERAL_BOTH =
       CompileTimeErrorCode(
     'AMBIGUOUS_SET_OR_MAP_LITERAL_BOTH',
-    "The literal can't be either a map or a set because it contains at least one literal map entry or a spread operator spreading a 'Map', and at least one element which is neither of these.",
+    "The literal can't be either a map or a set because it contains at least "
+        "one literal map entry or a spread operator spreading a 'Map', and at "
+        "least one element which is neither of these.",
     correctionMessage:
-        "Try removing or changing some of the elements so that all of the elements are consistent.",
+        "Try removing or changing some of the elements so that all of the "
+        "elements are consistent.",
     hasPublishedDocs: true,
   );
 
@@ -460,9 +467,11 @@
   static const CompileTimeErrorCode AMBIGUOUS_SET_OR_MAP_LITERAL_EITHER =
       CompileTimeErrorCode(
     'AMBIGUOUS_SET_OR_MAP_LITERAL_EITHER',
-    "This literal must be either a map or a set, but the elements don't have enough information for type inference to work.",
+    "This literal must be either a map or a set, but the elements don't have "
+        "enough information for type inference to work.",
     correctionMessage:
-        "Try adding type arguments to the literal (one for sets, two for maps).",
+        "Try adding type arguments to the literal (one for sets, two for "
+        "maps).",
     hasPublishedDocs: true,
   );
 
@@ -635,7 +644,8 @@
     'ASSIGNMENT_TO_CONST',
     "Constant variables can't be assigned a value.",
     correctionMessage:
-        "Try removing the assignment, or remove the modifier 'const' from the variable.",
+        "Try removing the assignment, or remove the modifier 'const' from the "
+        "variable.",
     hasPublishedDocs: true,
   );
 
@@ -785,7 +795,8 @@
     'ASSIGNMENT_TO_FINAL_NO_SETTER',
     "There isn’t a setter named '{0}' in class '{1}'.",
     correctionMessage:
-        "Try correcting the name to reference an existing setter, or declare the setter.",
+        "Try correcting the name to reference an existing setter, or declare "
+        "the setter.",
     hasPublishedDocs: true,
   );
 
@@ -974,7 +985,8 @@
     'ASYNC_FOR_IN_WRONG_CONTEXT',
     "The async for-in loop can only be used in an async function.",
     correctionMessage:
-        "Try marking the function body with either 'async' or 'async*', or removing the 'await' before the for-in loop.",
+        "Try marking the function body with either 'async' or 'async*', or "
+        "removing the 'await' before the for-in loop.",
     hasPublishedDocs: true,
   );
 
@@ -1020,9 +1032,11 @@
   static const CompileTimeErrorCode AWAIT_IN_LATE_LOCAL_VARIABLE_INITIALIZER =
       CompileTimeErrorCode(
     'AWAIT_IN_LATE_LOCAL_VARIABLE_INITIALIZER',
-    "The 'await' expression can't be used in a 'late' local variable's initializer.",
+    "The 'await' expression can't be used in a 'late' local variable's "
+        "initializer.",
     correctionMessage:
-        "Try removing the 'late' modifier, or rewriting the initializer without using the 'await' expression.",
+        "Try removing the 'late' modifier, or rewriting the initializer "
+        "without using the 'await' expression.",
     hasPublishedDocs: true,
   );
 
@@ -1101,20 +1115,23 @@
   // }
   // ```
   //
-  // If the method intentionally returns `null` at the end, then change the
+  // If the method intentionally returns `null` at the end, then add an
+  // explicit return of `null` at the end of the method and change the
   // return type so that it's valid to return `null`:
   //
   // ```dart
   // class C<T> {
   //   T? m(T t) {
   //     print(t);
+  //     return null;
   //   }
   // }
   // ```
   static const CompileTimeErrorCode BODY_MIGHT_COMPLETE_NORMALLY =
       CompileTimeErrorCode(
     'BODY_MIGHT_COMPLETE_NORMALLY',
-    "The body might complete normally, causing 'null' to be returned, but the return type is a potentially non-nullable type.",
+    "The body might complete normally, causing 'null' to be returned, but the "
+        "return type, '{0}', is a potentially non-nullable type.",
     correctionMessage:
         "Try adding either a return or a throw statement at the end.",
     hasPublishedDocs: true,
@@ -1342,7 +1359,8 @@
   static const CompileTimeErrorCode CASE_BLOCK_NOT_TERMINATED =
       CompileTimeErrorCode(
     'CASE_BLOCK_NOT_TERMINATED',
-    "The last statement of the 'case' should be 'break', 'continue', 'rethrow', 'return', or 'throw'.",
+    "The last statement of the 'case' should be 'break', 'continue', "
+        "'rethrow', 'return', or 'throw'.",
     correctionMessage: "Try adding one of the required statements.",
     hasPublishedDocs: true,
   );
@@ -1506,7 +1524,8 @@
       CASE_EXPRESSION_TYPE_IS_NOT_SWITCH_EXPRESSION_SUBTYPE =
       CompileTimeErrorCode(
     'CASE_EXPRESSION_TYPE_IS_NOT_SWITCH_EXPRESSION_SUBTYPE',
-    "The switch case expression type '{0}' must be a subtype of the switch expression type '{1}'.",
+    "The switch case expression type '{0}' must be a subtype of the switch "
+        "expression type '{1}'.",
     hasPublishedDocs: true,
   );
 
@@ -1540,7 +1559,8 @@
     'CAST_TO_NON_TYPE',
     "The name '{0}' isn't a type, so it can't be used in an 'as' expression.",
     correctionMessage:
-        "Try changing the name to the name of an existing type, or creating a type with the name '{0}'.",
+        "Try changing the name to the name of an existing type, or creating a "
+        "type with the name '{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -1566,7 +1586,8 @@
     'CLASS_INSTANTIATION_ACCESS_TO_MEMBER',
     "The static member '{0}' can't be accessed on a class instantiation.",
     correctionMessage:
-        "Try removing the type arguments from the class name, or changing the member name to the name of a constructor.",
+        "Try removing the type arguments from the class name, or changing the "
+        "member name to the name of a constructor.",
     uniqueName: 'CLASS_INSTANTIATION_ACCESS_TO_STATIC_MEMBER',
   );
 
@@ -1579,7 +1600,8 @@
     'CLASS_INSTANTIATION_ACCESS_TO_MEMBER',
     "The class '{0} doesn't have a constructor named '{1}.",
     correctionMessage:
-        "Try invoking a different constructor, or defining a constructor named '{1}'.",
+        "Try invoking a different constructor, or defining a constructor named "
+        "'{1}'.",
     uniqueName: 'CLASS_INSTANTIATION_ACCESS_TO_UNKNOWN_MEMBER',
   );
 
@@ -1671,7 +1693,8 @@
   static const CompileTimeErrorCode CONFLICTING_CONSTRUCTOR_AND_STATIC_FIELD =
       CompileTimeErrorCode(
     'CONFLICTING_CONSTRUCTOR_AND_STATIC_MEMBER',
-    "'{0}' can't be used to name both a constructor and a static field in this class.",
+    "'{0}' can't be used to name both a constructor and a static field in this "
+        "class.",
     correctionMessage: "Try renaming either the constructor or the field.",
     hasPublishedDocs: true,
     uniqueName: 'CONFLICTING_CONSTRUCTOR_AND_STATIC_FIELD',
@@ -1684,7 +1707,8 @@
   static const CompileTimeErrorCode CONFLICTING_CONSTRUCTOR_AND_STATIC_GETTER =
       CompileTimeErrorCode(
     'CONFLICTING_CONSTRUCTOR_AND_STATIC_MEMBER',
-    "'{0}' can't be used to name both a constructor and a static getter in this class.",
+    "'{0}' can't be used to name both a constructor and a static getter in "
+        "this class.",
     correctionMessage: "Try renaming either the constructor or the getter.",
     hasPublishedDocs: true,
     uniqueName: 'CONFLICTING_CONSTRUCTOR_AND_STATIC_GETTER',
@@ -1697,7 +1721,8 @@
   static const CompileTimeErrorCode CONFLICTING_CONSTRUCTOR_AND_STATIC_METHOD =
       CompileTimeErrorCode(
     'CONFLICTING_CONSTRUCTOR_AND_STATIC_MEMBER',
-    "'{0}' can't be used to name both a constructor and a static method in this class.",
+    "'{0}' can't be used to name both a constructor and a static method in "
+        "this class.",
     correctionMessage: "Try renaming either the constructor or the method.",
     hasPublishedDocs: true,
     uniqueName: 'CONFLICTING_CONSTRUCTOR_AND_STATIC_METHOD',
@@ -1710,7 +1735,8 @@
   static const CompileTimeErrorCode CONFLICTING_CONSTRUCTOR_AND_STATIC_SETTER =
       CompileTimeErrorCode(
     'CONFLICTING_CONSTRUCTOR_AND_STATIC_MEMBER',
-    "'{0}' can't be used to name both a constructor and a static setter in this class.",
+    "'{0}' can't be used to name both a constructor and a static setter in "
+        "this class.",
     correctionMessage: "Try renaming either the constructor or the setter.",
     hasPublishedDocs: true,
     uniqueName: 'CONFLICTING_CONSTRUCTOR_AND_STATIC_SETTER',
@@ -1729,9 +1755,11 @@
   static const CompileTimeErrorCode CONFLICTING_FIELD_AND_METHOD =
       CompileTimeErrorCode(
     'CONFLICTING_FIELD_AND_METHOD',
-    "Class '{0}' can't define field '{1}' and have method '{2}.{1}' with the same name.",
+    "Class '{0}' can't define field '{1}' and have method '{2}.{1}' with the "
+        "same name.",
     correctionMessage:
-        "Try converting the getter to a method, or renaming the field to a name that doesn't conflict.",
+        "Try converting the getter to a method, or renaming the field to a "
+        "name that doesn't conflict.",
   );
 
   /**
@@ -1774,7 +1802,8 @@
   static const CompileTimeErrorCode CONFLICTING_GENERIC_INTERFACES =
       CompileTimeErrorCode(
     'CONFLICTING_GENERIC_INTERFACES',
-    "The class '{0}' can't implement both '{1}' and '{2}' because the type arguments are different.",
+    "The class '{0}' can't implement both '{1}' and '{2}' because the type "
+        "arguments are different.",
     hasPublishedDocs: true,
   );
 
@@ -1791,9 +1820,11 @@
   static const CompileTimeErrorCode CONFLICTING_METHOD_AND_FIELD =
       CompileTimeErrorCode(
     'CONFLICTING_METHOD_AND_FIELD',
-    "Class '{0}' can't define method '{1}' and have field '{2}.{1}' with the same name.",
+    "Class '{0}' can't define method '{1}' and have field '{2}.{1}' with the "
+        "same name.",
     correctionMessage:
-        "Try converting the method to a getter, or renaming the method to a name that doesn't conflict.",
+        "Try converting the method to a getter, or renaming the method to a "
+        "name that doesn't conflict.",
   );
 
   /**
@@ -1809,7 +1840,8 @@
   static const CompileTimeErrorCode CONFLICTING_STATIC_AND_INSTANCE =
       CompileTimeErrorCode(
     'CONFLICTING_STATIC_AND_INSTANCE',
-    "Class '{0}' can't define static member '{1}' and have instance member '{2}.{1}' with the same name.",
+    "Class '{0}' can't define static member '{1}' and have instance member "
+        "'{2}.{1}' with the same name.",
     correctionMessage:
         "Try renaming the member to a name that doesn't conflict.",
   );
@@ -1843,7 +1875,8 @@
   static const CompileTimeErrorCode CONFLICTING_TYPE_VARIABLE_AND_CLASS =
       CompileTimeErrorCode(
     'CONFLICTING_TYPE_VARIABLE_AND_CONTAINER',
-    "'{0}' can't be used to name both a type variable and the class in which the type variable is defined.",
+    "'{0}' can't be used to name both a type variable and the class in which "
+        "the type variable is defined.",
     correctionMessage: "Try renaming either the type variable or the class.",
     hasPublishedDocs: true,
     uniqueName: 'CONFLICTING_TYPE_VARIABLE_AND_CLASS',
@@ -1856,7 +1889,8 @@
   static const CompileTimeErrorCode CONFLICTING_TYPE_VARIABLE_AND_EXTENSION =
       CompileTimeErrorCode(
     'CONFLICTING_TYPE_VARIABLE_AND_CONTAINER',
-    "'{0}' can't be used to name both a type variable and the extension in which the type variable is defined.",
+    "'{0}' can't be used to name both a type variable and the extension in "
+        "which the type variable is defined.",
     correctionMessage:
         "Try renaming either the type variable or the extension.",
     hasPublishedDocs: true,
@@ -1896,7 +1930,8 @@
   static const CompileTimeErrorCode CONFLICTING_TYPE_VARIABLE_AND_MEMBER_CLASS =
       CompileTimeErrorCode(
     'CONFLICTING_TYPE_VARIABLE_AND_MEMBER',
-    "'{0}' can't be used to name both a type variable and a member in this class.",
+    "'{0}' can't be used to name both a type variable and a member in this "
+        "class.",
     correctionMessage: "Try renaming either the type variable or the member.",
     hasPublishedDocs: true,
     uniqueName: 'CONFLICTING_TYPE_VARIABLE_AND_MEMBER_CLASS',
@@ -1909,7 +1944,8 @@
   static const CompileTimeErrorCode
       CONFLICTING_TYPE_VARIABLE_AND_MEMBER_EXTENSION = CompileTimeErrorCode(
     'CONFLICTING_TYPE_VARIABLE_AND_MEMBER',
-    "'{0}' can't be used to name both a type variable and a member in this extension.",
+    "'{0}' can't be used to name both a type variable and a member in this "
+        "extension.",
     correctionMessage: "Try renaming either the type variable or the member.",
     hasPublishedDocs: true,
     uniqueName: 'CONFLICTING_TYPE_VARIABLE_AND_MEMBER_EXTENSION',
@@ -1922,7 +1958,8 @@
   static const CompileTimeErrorCode CONFLICTING_TYPE_VARIABLE_AND_MEMBER_MIXIN =
       CompileTimeErrorCode(
     'CONFLICTING_TYPE_VARIABLE_AND_MEMBER',
-    "'{0}' can't be used to name both a type variable and a member in this mixin.",
+    "'{0}' can't be used to name both a type variable and a member in this "
+        "mixin.",
     correctionMessage: "Try renaming either the type variable or the member.",
     hasPublishedDocs: true,
     uniqueName: 'CONFLICTING_TYPE_VARIABLE_AND_MEMBER_MIXIN',
@@ -1935,7 +1972,8 @@
   static const CompileTimeErrorCode CONFLICTING_TYPE_VARIABLE_AND_MIXIN =
       CompileTimeErrorCode(
     'CONFLICTING_TYPE_VARIABLE_AND_CONTAINER',
-    "'{0}' can't be used to name both a type variable and the mixin in which the type variable is defined.",
+    "'{0}' can't be used to name both a type variable and the mixin in which "
+        "the type variable is defined.",
     correctionMessage: "Try renaming either the type variable or the mixin.",
     hasPublishedDocs: true,
     uniqueName: 'CONFLICTING_TYPE_VARIABLE_AND_MIXIN',
@@ -1948,7 +1986,8 @@
   static const CompileTimeErrorCode CONST_CONSTRUCTOR_FIELD_TYPE_MISMATCH =
       CompileTimeErrorCode(
     'CONST_CONSTRUCTOR_FIELD_TYPE_MISMATCH',
-    "In a const constructor, a value of type '{0}' can't be assigned to the field '{1}', which has type '{2}'.",
+    "In a const constructor, a value of type '{0}' can't be assigned to the "
+        "field '{1}', which has type '{2}'.",
     correctionMessage: "Try using a subtype, or removing the keyword 'const'.",
   );
 
@@ -2002,7 +2041,8 @@
   static const CompileTimeErrorCode CONST_CONSTRUCTOR_PARAM_TYPE_MISMATCH =
       CompileTimeErrorCode(
     'CONST_CONSTRUCTOR_PARAM_TYPE_MISMATCH',
-    "A value of type '{0}' can't be assigned to a parameter of type '{1}' in a const constructor.",
+    "A value of type '{0}' can't be assigned to a parameter of type '{1}' in a "
+        "const constructor.",
     correctionMessage: "Try using a subtype, or removing the keyword 'const'.",
     hasPublishedDocs: true,
   );
@@ -2065,9 +2105,11 @@
       CONST_CONSTRUCTOR_WITH_FIELD_INITIALIZED_BY_NON_CONST =
       CompileTimeErrorCode(
     'CONST_CONSTRUCTOR_WITH_FIELD_INITIALIZED_BY_NON_CONST',
-    "Can't define the 'const' constructor because the field '{0}' is initialized with a non-constant value.",
+    "Can't define the 'const' constructor because the field '{0}' is "
+        "initialized with a non-constant value.",
     correctionMessage:
-        "Try initializing the field to a constant value, or removing the keyword 'const' from the constructor.",
+        "Try initializing the field to a constant value, or removing the "
+        "keyword 'const' from the constructor.",
     hasPublishedDocs: true,
   );
 
@@ -2088,9 +2130,11 @@
   static const CompileTimeErrorCode CONST_CONSTRUCTOR_WITH_MIXIN_WITH_FIELD =
       CompileTimeErrorCode(
     'CONST_CONSTRUCTOR_WITH_MIXIN_WITH_FIELD',
-    "This constructor can't be declared 'const' because a mixin adds the instance field: {0}.",
+    "This constructor can't be declared 'const' because a mixin adds the "
+        "instance field: {0}.",
     correctionMessage:
-        "Try removing the 'const' keyword or removing the 'with' clause from the class declaration, or removing the field from the mixin class.",
+        "Try removing the 'const' keyword or removing the 'with' clause from "
+        "the class declaration, or removing the field from the mixin class.",
   );
 
   /**
@@ -2110,9 +2154,11 @@
   static const CompileTimeErrorCode CONST_CONSTRUCTOR_WITH_MIXIN_WITH_FIELDS =
       CompileTimeErrorCode(
     'CONST_CONSTRUCTOR_WITH_MIXIN_WITH_FIELD',
-    "This constructor can't be declared 'const' because the mixins add the instance fields: {0}.",
+    "This constructor can't be declared 'const' because the mixins add the "
+        "instance fields: {0}.",
     correctionMessage:
-        "Try removing the 'const' keyword or removing the 'with' clause from the class declaration, or removing the fields from the mixin classes.",
+        "Try removing the 'const' keyword or removing the 'with' clause from "
+        "the class declaration, or removing the fields from the mixin classes.",
     uniqueName: 'CONST_CONSTRUCTOR_WITH_MIXIN_WITH_FIELDS',
   );
 
@@ -2190,9 +2236,11 @@
   static const CompileTimeErrorCode CONST_CONSTRUCTOR_WITH_NON_CONST_SUPER =
       CompileTimeErrorCode(
     'CONST_CONSTRUCTOR_WITH_NON_CONST_SUPER',
-    "A constant constructor can't call a non-constant super constructor of '{0}'.",
+    "A constant constructor can't call a non-constant super constructor of "
+        "'{0}'.",
     correctionMessage:
-        "Try calling a constant constructor in the superclass, or removing the keyword 'const' from the constructor.",
+        "Try calling a constant constructor in the superclass, or removing the "
+        "keyword 'const' from the constructor.",
     hasPublishedDocs: true,
   );
 
@@ -2245,7 +2293,8 @@
     'CONST_CONSTRUCTOR_WITH_NON_FINAL_FIELD',
     "Can't define a const constructor for a class with non-final fields.",
     correctionMessage:
-        "Try making all of the fields final, or removing the keyword 'const' from the constructor.",
+        "Try making all of the fields final, or removing the keyword 'const' "
+        "from the constructor.",
     hasPublishedDocs: true,
   );
 
@@ -2296,7 +2345,8 @@
     'CONST_DEFERRED_CLASS',
     "Deferred classes can't be created with 'const'.",
     correctionMessage:
-        "Try using 'new' to create the instance, or changing the import to not be deferred.",
+        "Try using 'new' to create the instance, or changing the import to not "
+        "be deferred.",
     hasPublishedDocs: true,
   );
 
@@ -2317,7 +2367,8 @@
   static const CompileTimeErrorCode CONST_EVAL_THROWS_IDBZE =
       CompileTimeErrorCode(
     'CONST_EVAL_THROWS_IDBZE',
-    "Evaluation of this constant expression throws an IntegerDivisionByZeroException.",
+    "Evaluation of this constant expression throws an "
+        "IntegerDivisionByZeroException.",
   );
 
   /**
@@ -2327,7 +2378,8 @@
    */
   static const CompileTimeErrorCode CONST_EVAL_TYPE_BOOL = CompileTimeErrorCode(
     'CONST_EVAL_TYPE_BOOL',
-    "In constant expressions, operands of this operator must be of type 'bool'.",
+    "In constant expressions, operands of this operator must be of type "
+        "'bool'.",
   );
 
   /**
@@ -2338,7 +2390,8 @@
   static const CompileTimeErrorCode CONST_EVAL_TYPE_BOOL_INT =
       CompileTimeErrorCode(
     'CONST_EVAL_TYPE_BOOL_INT',
-    "In constant expressions, operands of this operator must be of type 'bool' or 'int'.",
+    "In constant expressions, operands of this operator must be of type 'bool' "
+        "or 'int'.",
   );
 
   /**
@@ -2349,7 +2402,8 @@
   static const CompileTimeErrorCode CONST_EVAL_TYPE_BOOL_NUM_STRING =
       CompileTimeErrorCode(
     'CONST_EVAL_TYPE_BOOL_NUM_STRING',
-    "In constant expressions, operands of this operator must be of type 'bool', 'num', 'String' or 'null'.",
+    "In constant expressions, operands of this operator must be of type "
+        "'bool', 'num', 'String' or 'null'.",
   );
 
   /**
@@ -2375,7 +2429,8 @@
 
   static const CompileTimeErrorCode CONST_EVAL_TYPE_TYPE = CompileTimeErrorCode(
     'CONST_EVAL_TYPE_TYPE',
-    "In constant expressions, operands of this operator must be of type 'Type'.",
+    "In constant expressions, operands of this operator must be of type "
+        "'Type'.",
   );
 
   /**
@@ -2386,7 +2441,8 @@
   static const CompileTimeErrorCode CONST_FIELD_INITIALIZER_NOT_ASSIGNABLE =
       CompileTimeErrorCode(
     'FIELD_INITIALIZER_NOT_ASSIGNABLE',
-    "The initializer type '{0}' can't be assigned to the field type '{1}' in a const constructor.",
+    "The initializer type '{0}' can't be assigned to the field type '{1}' in a "
+        "const constructor.",
     correctionMessage: "Try using a subtype, or removing the 'const' keyword",
     hasPublishedDocs: true,
     uniqueName: 'CONST_FIELD_INITIALIZER_NOT_ASSIGNABLE',
@@ -2483,9 +2539,11 @@
       CONST_INITIALIZED_WITH_NON_CONSTANT_VALUE_FROM_DEFERRED_LIBRARY =
       CompileTimeErrorCode(
     'CONST_INITIALIZED_WITH_NON_CONSTANT_VALUE_FROM_DEFERRED_LIBRARY',
-    "Constant values from a deferred library can't be used to initialize a 'const' variable.",
+    "Constant values from a deferred library can't be used to initialize a "
+        "'const' variable.",
     correctionMessage:
-        "Try initializing the variable without referencing members of the deferred library, or changing the import to not be deferred.",
+        "Try initializing the variable without referencing members of the "
+        "deferred library, or changing the import to not be deferred.",
     hasPublishedDocs: true,
   );
 
@@ -2589,9 +2647,11 @@
   static const CompileTimeErrorCode
       CONST_MAP_KEY_EXPRESSION_TYPE_IMPLEMENTS_EQUALS = CompileTimeErrorCode(
     'CONST_MAP_KEY_EXPRESSION_TYPE_IMPLEMENTS_EQUALS',
-    "The type of a key in a constant map can't override the '==' operator, but the class '{0}' does.",
+    "The type of a key in a constant map can't override the '==' operator, but "
+        "the class '{0}' does.",
     correctionMessage:
-        "Try using a different value for the key, or removing the keyword 'const' from the map.",
+        "Try using a different value for the key, or removing the keyword "
+        "'const' from the map.",
     hasPublishedDocs: true,
   );
 
@@ -2682,9 +2742,11 @@
   static const CompileTimeErrorCode CONST_SET_ELEMENT_TYPE_IMPLEMENTS_EQUALS =
       CompileTimeErrorCode(
     'CONST_SET_ELEMENT_TYPE_IMPLEMENTS_EQUALS',
-    "The type of an element in a constant set can't override the '==' operator, but the type '{0}' does.",
+    "The type of an element in a constant set can't override the '==' "
+        "operator, but the type '{0}' does.",
     correctionMessage:
-        "Try using a different value for the element, or removing the keyword 'const' from the set.",
+        "Try using a different value for the element, or removing the keyword "
+        "'const' from the set.",
     hasPublishedDocs: true,
   );
 
@@ -2848,7 +2910,8 @@
     'CONST_WITH_NON_CONSTANT_ARGUMENT',
     "Arguments of a constant creation must be constant expressions.",
     correctionMessage:
-        "Try making the argument a valid constant, or use 'new' to call the constructor.",
+        "Try making the argument a valid constant, or use 'new' to call the "
+        "constructor.",
     hasPublishedDocs: true,
   );
 
@@ -2926,7 +2989,8 @@
   static const CompileTimeErrorCode
       CONST_WITH_TYPE_PARAMETERS_CONSTRUCTOR_TEAROFF = CompileTimeErrorCode(
     'CONST_WITH_TYPE_PARAMETERS',
-    "A constant constructor tearoff can't use a type parameter as a type argument.",
+    "A constant constructor tearoff can't use a type parameter as a type "
+        "argument.",
     correctionMessage:
         "Try replacing the type parameter with a different type.",
     hasPublishedDocs: true,
@@ -2939,7 +3003,8 @@
   static const CompileTimeErrorCode
       CONST_WITH_TYPE_PARAMETERS_FUNCTION_TEAROFF = CompileTimeErrorCode(
     'CONST_WITH_TYPE_PARAMETERS',
-    "A constant function tearoff can't use a type parameter as a type argument.",
+    "A constant function tearoff can't use a type parameter as a type "
+        "argument.",
     correctionMessage:
         "Try replacing the type parameter with a different type.",
     hasPublishedDocs: true,
@@ -3033,7 +3098,8 @@
   static const CompileTimeErrorCode DEFAULT_LIST_CONSTRUCTOR =
       CompileTimeErrorCode(
     'DEFAULT_LIST_CONSTRUCTOR',
-    "The default 'List' constructor isn't available when null safety is enabled.",
+    "The default 'List' constructor isn't available when null safety is "
+        "enabled.",
     correctionMessage:
         "Try using a list literal, 'List.filled' or 'List.generate'.",
     hasPublishedDocs: true,
@@ -3093,7 +3159,8 @@
   static const CompileTimeErrorCode
       DEFAULT_VALUE_IN_REDIRECTING_FACTORY_CONSTRUCTOR = CompileTimeErrorCode(
     'DEFAULT_VALUE_IN_REDIRECTING_FACTORY_CONSTRUCTOR',
-    "Default values aren't allowed in factory constructors that redirect to another constructor.",
+    "Default values aren't allowed in factory constructors that redirect to "
+        "another constructor.",
     correctionMessage: "Try removing the default value.",
     hasPublishedDocs: true,
   );
@@ -3220,7 +3287,8 @@
     'DEFERRED_IMPORT_OF_EXTENSION',
     "Imports of deferred libraries must hide all extensions.",
     correctionMessage:
-        "Try adding either a show combinator listing the names you need to reference or a hide combinator listing all of the extensions.",
+        "Try adding either a show combinator listing the names you need to "
+        "reference or a hide combinator listing all of the extensions.",
     hasPublishedDocs: true,
   );
 
@@ -3272,9 +3340,11 @@
   static const CompileTimeErrorCode DISALLOWED_TYPE_INSTANTIATION_EXPRESSION =
       CompileTimeErrorCode(
     'DISALLOWED_TYPE_INSTANTIATION_EXPRESSION',
-    "Only a generic type, generic function, generic instance method, or generic constructor can be type instantiated.",
+    "Only a generic type, generic function, generic instance method, or "
+        "generic constructor can be type instantiated.",
     correctionMessage:
-        "Try instantiating the type(s) of a generic type, generic function, generic instance method, or generic constructor.",
+        "Try instantiating the type(s) of a generic type, generic function, "
+        "generic instance method, or generic constructor.",
   );
 
   /**
@@ -3444,7 +3514,8 @@
   static const CompileTimeErrorCode DUPLICATE_FIELD_FORMAL_PARAMETER =
       CompileTimeErrorCode(
     'DUPLICATE_FIELD_FORMAL_PARAMETER',
-    "The field '{0}' can't be initialized by multiple parameters in the same constructor.",
+    "The field '{0}' can't be initialized by multiple parameters in the same "
+        "constructor.",
     correctionMessage:
         "Try removing one of the parameters, or using different fields.",
     hasPublishedDocs: true,
@@ -3507,7 +3578,8 @@
     'DUPLICATE_NAMED_ARGUMENT',
     "The argument for the named parameter '{0}' was already specified.",
     correctionMessage:
-        "Try removing one of the named arguments, or correcting one of the names to reference a different named parameter.",
+        "Try removing one of the named arguments, or correcting one of the "
+        "names to reference a different named parameter.",
     hasPublishedDocs: true,
   );
 
@@ -3824,7 +3896,8 @@
   // names declared in the opted-out library.
   static const CompileTimeErrorCode EXPORT_LEGACY_SYMBOL = CompileTimeErrorCode(
     'EXPORT_LEGACY_SYMBOL',
-    "The symbol '{0}' is defined in a legacy library, and can't be re-exported from a library with null safety enabled.",
+    "The symbol '{0}' is defined in a legacy library, and can't be re-exported "
+        "from a library with null safety enabled.",
     correctionMessage:
         "Try removing the export or migrating the legacy library.",
     hasPublishedDocs: true,
@@ -3949,7 +4022,8 @@
     'SUBTYPE_OF_DEFERRED_CLASS',
     "Classes can't extend deferred classes.",
     correctionMessage:
-        "Try specifying a different superclass, or removing the extends clause.",
+        "Try specifying a different superclass, or removing the extends "
+        "clause.",
     hasPublishedDocs: true,
     uniqueName: 'EXTENDS_DEFERRED_CLASS',
   );
@@ -4015,7 +4089,8 @@
     'SUBTYPE_OF_DISALLOWED_TYPE',
     "Classes can't extend '{0}'.",
     correctionMessage:
-        "Try specifying a different superclass, or removing the extends clause.",
+        "Try specifying a different superclass, or removing the extends "
+        "clause.",
     hasPublishedDocs: true,
     uniqueName: 'EXTENDS_DISALLOWED_CLASS',
   );
@@ -4064,7 +4139,8 @@
     'EXTENDS_NON_CLASS',
     "Classes can only extend other classes.",
     correctionMessage:
-        "Try specifying a different superclass, or removing the extends clause.",
+        "Try specifying a different superclass, or removing the extends "
+        "clause.",
     hasPublishedDocs: true,
     isUnresolvedIdentifier: true,
   );
@@ -4102,9 +4178,11 @@
   static const CompileTimeErrorCode
       EXTENDS_TYPE_ALIAS_EXPANDS_TO_TYPE_PARAMETER = CompileTimeErrorCode(
     'SUPERTYPE_EXPANDS_TO_TYPE_PARAMETER',
-    "A type alias that expands to a type parameter can't be used as a superclass.",
+    "A type alias that expands to a type parameter can't be used as a "
+        "superclass.",
     correctionMessage:
-        "Try specifying a different superclass, or removing the extends clause.",
+        "Try specifying a different superclass, or removing the extends "
+        "clause.",
     hasPublishedDocs: true,
     uniqueName: 'EXTENDS_TYPE_ALIAS_EXPANDS_TO_TYPE_PARAMETER',
   );
@@ -4191,7 +4269,8 @@
   static const CompileTimeErrorCode EXTENSION_CONFLICTING_STATIC_AND_INSTANCE =
       CompileTimeErrorCode(
     'EXTENSION_CONFLICTING_STATIC_AND_INSTANCE',
-    "An extension can't define static member '{0}' and an instance member with the same name.",
+    "An extension can't define static member '{0}' and an instance member with "
+        "the same name.",
     correctionMessage:
         "Try renaming the member to a name that doesn't conflict.",
     hasPublishedDocs: true,
@@ -4231,7 +4310,8 @@
   static const CompileTimeErrorCode EXTENSION_DECLARES_MEMBER_OF_OBJECT =
       CompileTimeErrorCode(
     'EXTENSION_DECLARES_MEMBER_OF_OBJECT',
-    "Extensions can't declare members with the same name as a member declared by 'Object'.",
+    "Extensions can't declare members with the same name as a member declared "
+        "by 'Object'.",
     correctionMessage: "Try specifying a different name for the member.",
     hasPublishedDocs: true,
   );
@@ -4276,7 +4356,8 @@
   static const CompileTimeErrorCode EXTENSION_OVERRIDE_ACCESS_TO_STATIC_MEMBER =
       CompileTimeErrorCode(
     'EXTENSION_OVERRIDE_ACCESS_TO_STATIC_MEMBER',
-    "An extension override can't be used to access a static member from an extension.",
+    "An extension override can't be used to access a static member from an "
+        "extension.",
     correctionMessage: "Try using just the name of the extension.",
     hasPublishedDocs: true,
   );
@@ -4326,7 +4407,8 @@
   static const CompileTimeErrorCode EXTENSION_OVERRIDE_ARGUMENT_NOT_ASSIGNABLE =
       CompileTimeErrorCode(
     'EXTENSION_OVERRIDE_ARGUMENT_NOT_ASSIGNABLE',
-    "The type of the argument to the extension override '{0}' isn't assignable to the extended type '{1}'.",
+    "The type of the argument to the extension override '{0}' isn't assignable "
+        "to the extended type '{1}'.",
     hasPublishedDocs: true,
   );
 
@@ -4431,7 +4513,8 @@
   static const CompileTimeErrorCode EXTENSION_OVERRIDE_WITH_CASCADE =
       CompileTimeErrorCode(
     'EXTENSION_OVERRIDE_WITH_CASCADE',
-    "Extension overrides have no value so they can't be used as the receiver of a cascade expression.",
+    "Extension overrides have no value so they can't be used as the receiver "
+        "of a cascade expression.",
     correctionMessage: "Try using '.' instead of '..'.",
     hasPublishedDocs: true,
   );
@@ -4441,7 +4524,8 @@
     'EXTERNAL_FIELD_CONSTRUCTOR_INITIALIZER',
     "External fields cannot have initializers.",
     correctionMessage:
-        "Try removing the field initializer or the 'external' keyword from the field declaration.",
+        "Try removing the field initializer or the 'external' keyword from the "
+        "field declaration.",
   );
 
   static const CompileTimeErrorCode EXTERNAL_FIELD_INITIALIZER =
@@ -4553,7 +4637,8 @@
     'EXTRA_POSITIONAL_ARGUMENTS_COULD_BE_NAMED',
     "Too many positional arguments: {0} expected, but {1} found.",
     correctionMessage:
-        "Try removing the extra positional arguments, or specifying the name for named arguments.",
+        "Try removing the extra positional arguments, or specifying the name "
+        "for named arguments.",
     hasPublishedDocs: true,
   );
 
@@ -4646,7 +4731,8 @@
   static const CompileTimeErrorCode
       FIELD_INITIALIZED_IN_INITIALIZER_AND_DECLARATION = CompileTimeErrorCode(
     'FIELD_INITIALIZED_IN_INITIALIZER_AND_DECLARATION',
-    "Fields can't be initialized in the constructor if they are final and were already initialized at their declaration.",
+    "Fields can't be initialized in the constructor if they are final and were "
+        "already initialized at their declaration.",
     correctionMessage: "Try removing one of the initializations.",
     hasPublishedDocs: true,
   );
@@ -4709,7 +4795,8 @@
   static const CompileTimeErrorCode
       FIELD_INITIALIZED_IN_PARAMETER_AND_INITIALIZER = CompileTimeErrorCode(
     'FIELD_INITIALIZED_IN_PARAMETER_AND_INITIALIZER',
-    "Fields can't be initialized in both the parameter list and the initializers.",
+    "Fields can't be initialized in both the parameter list and the "
+        "initializers.",
     correctionMessage: "Try removing one of the initializations.",
     hasPublishedDocs: true,
   );
@@ -4962,7 +5049,8 @@
     'FIELD_INITIALIZING_FORMAL_NOT_ASSIGNABLE',
     "The parameter type '{0}' is incompatible with the field type '{1}'.",
     correctionMessage:
-        "Try changing or removing the parameter's type, or changing the field's type.",
+        "Try changing or removing the parameter's type, or changing the "
+        "field's type.",
     hasPublishedDocs: true,
   );
 
@@ -5014,7 +5102,8 @@
   static const CompileTimeErrorCode
       FINAL_INITIALIZED_IN_DECLARATION_AND_CONSTRUCTOR = CompileTimeErrorCode(
     'FINAL_INITIALIZED_IN_DECLARATION_AND_CONSTRUCTOR',
-    "'{0}' is final and was given a value when it was declared, so it can't be set to a new value.",
+    "'{0}' is final and was given a value when it was declared, so it can't be "
+        "set to a new value.",
     correctionMessage: "Try removing one of the initializations.",
     hasPublishedDocs: true,
   );
@@ -5190,7 +5279,8 @@
   static const CompileTimeErrorCode FINAL_NOT_INITIALIZED_CONSTRUCTOR_3_PLUS =
       CompileTimeErrorCode(
     'FINAL_NOT_INITIALIZED_CONSTRUCTOR',
-    "All final variables must be initialized, but '{0}', '{1}', and {2} others aren't.",
+    "All final variables must be initialized, but '{0}', '{1}', and {2} others "
+        "aren't.",
     correctionMessage: "Try adding initializers for the fields.",
     hasPublishedDocs: true,
     uniqueName: 'FINAL_NOT_INITIALIZED_CONSTRUCTOR_3_PLUS',
@@ -5248,7 +5338,8 @@
   static const CompileTimeErrorCode FOR_IN_OF_INVALID_ELEMENT_TYPE =
       CompileTimeErrorCode(
     'FOR_IN_OF_INVALID_ELEMENT_TYPE',
-    "The type '{0}' used in the 'for' loop must implement '{1}' with a type argument that can be assigned to '{2}'.",
+    "The type '{0}' used in the 'for' loop must implement '{1}' with a type "
+        "argument that can be assigned to '{2}'.",
     hasPublishedDocs: true,
   );
 
@@ -5335,7 +5426,8 @@
     'FOR_IN_WITH_CONST_VARIABLE',
     "A for-in loop variable can't be a 'const'.",
     correctionMessage:
-        "Try removing the 'const' modifier from the variable, or use a different variable.",
+        "Try removing the 'const' modifier from the variable, or use a "
+        "different variable.",
     hasPublishedDocs: true,
   );
 
@@ -5348,7 +5440,8 @@
     'GENERIC_FUNCTION_TYPE_CANNOT_BE_BOUND',
     "Generic function types can't be used as type parameter bounds",
     correctionMessage:
-        "Try making the free variable in the function type part of the larger declaration signature",
+        "Try making the free variable in the function type part of the larger "
+        "declaration signature",
   );
 
   /**
@@ -5360,7 +5453,8 @@
     'GENERIC_FUNCTION_TYPE_CANNOT_BE_TYPE_ARGUMENT',
     "A generic function type can't be a type argument.",
     correctionMessage:
-        "Try removing type parameters from the generic function type, or using 'dynamic' as the type argument here.",
+        "Try removing type parameters from the generic function type, or using "
+        "'dynamic' as the type argument here.",
   );
 
   /**
@@ -5407,9 +5501,11 @@
   static const CompileTimeErrorCode
       GENERIC_METHOD_TYPE_INSTANTIATION_ON_DYNAMIC = CompileTimeErrorCode(
     'GENERIC_METHOD_TYPE_INSTANTIATION_ON_DYNAMIC',
-    "A method tear-off on a receiver whose type is 'dynamic' can't have type arguments.",
+    "A method tear-off on a receiver whose type is 'dynamic' can't have type "
+        "arguments.",
     correctionMessage:
-        "Specify the type of the receiver, or remove the type arguments from the method tear-off.",
+        "Specify the type of the receiver, or remove the type arguments from "
+        "the method tear-off.",
     hasPublishedDocs: true,
   );
 
@@ -5423,7 +5519,8 @@
   static const CompileTimeErrorCode GETTER_NOT_ASSIGNABLE_SETTER_TYPES =
       CompileTimeErrorCode(
     'GETTER_NOT_ASSIGNABLE_SETTER_TYPES',
-    "The return type of getter '{0}' is '{1}' which isn't assignable to the type '{2}' of its setter '{3}'.",
+    "The return type of getter '{0}' is '{1}' which isn't assignable to the "
+        "type '{2}' of its setter '{3}'.",
     correctionMessage: "Try changing the types so that they are compatible.",
   );
 
@@ -5481,7 +5578,8 @@
   static const CompileTimeErrorCode GETTER_NOT_SUBTYPE_SETTER_TYPES =
       CompileTimeErrorCode(
     'GETTER_NOT_SUBTYPE_SETTER_TYPES',
-    "The return type of getter '{0}' is '{1}' which isn't a subtype of the type '{2}' of its setter '{3}'.",
+    "The return type of getter '{0}' is '{1}' which isn't a subtype of the "
+        "type '{2}' of its setter '{3}'.",
     correctionMessage: "Try changing the types so that they are compatible.",
     hasPublishedDocs: true,
   );
@@ -5489,7 +5587,8 @@
   static const CompileTimeErrorCode IF_ELEMENT_CONDITION_FROM_DEFERRED_LIBRARY =
       CompileTimeErrorCode(
     'IF_ELEMENT_CONDITION_FROM_DEFERRED_LIBRARY',
-    "Constant values from a deferred library can't be used as values in an if condition inside a const collection literal.",
+    "Constant values from a deferred library can't be used as values in an if "
+        "condition inside a const collection literal.",
     correctionMessage: "Try making the deferred import non-deferred.",
   );
 
@@ -5529,9 +5628,11 @@
   static const CompileTimeErrorCode ILLEGAL_ASYNC_GENERATOR_RETURN_TYPE =
       CompileTimeErrorCode(
     'ILLEGAL_ASYNC_GENERATOR_RETURN_TYPE',
-    "Functions marked 'async*' must have a return type that is a supertype of 'Stream<T>' for some type 'T'.",
+    "Functions marked 'async*' must have a return type that is a supertype of "
+        "'Stream<T>' for some type 'T'.",
     correctionMessage:
-        "Try fixing the return type of the function, or removing the modifier 'async*' from the function body.",
+        "Try fixing the return type of the function, or removing the modifier "
+        "'async*' from the function body.",
     hasPublishedDocs: true,
   );
 
@@ -5577,7 +5678,8 @@
     'ILLEGAL_ASYNC_RETURN_TYPE',
     "Functions marked 'async' must have a return type assignable to 'Future'.",
     correctionMessage:
-        "Try fixing the return type of the function, or removing the modifier 'async' from the function body.",
+        "Try fixing the return type of the function, or removing the modifier "
+        "'async' from the function body.",
     hasPublishedDocs: true,
   );
 
@@ -5618,9 +5720,11 @@
   static const CompileTimeErrorCode ILLEGAL_SYNC_GENERATOR_RETURN_TYPE =
       CompileTimeErrorCode(
     'ILLEGAL_SYNC_GENERATOR_RETURN_TYPE',
-    "Functions marked 'sync*' must have a return type that is a supertype of 'Iterable<T>' for some type 'T'.",
+    "Functions marked 'sync*' must have a return type that is a supertype of "
+        "'Iterable<T>' for some type 'T'.",
     correctionMessage:
-        "Try fixing the return type of the function, or removing the modifier 'sync*' from the function body.",
+        "Try fixing the return type of the function, or removing the modifier "
+        "'sync*' from the function body.",
     hasPublishedDocs: true,
   );
 
@@ -5632,7 +5736,8 @@
     'SUBTYPE_OF_DEFERRED_CLASS',
     "Classes and mixins can't implement deferred classes.",
     correctionMessage:
-        "Try specifying a different interface, removing the class from the list, or changing the import to not be deferred.",
+        "Try specifying a different interface, removing the class from the "
+        "list, or changing the import to not be deferred.",
     hasPublishedDocs: true,
     uniqueName: 'IMPLEMENTS_DEFERRED_CLASS',
   );
@@ -5646,7 +5751,8 @@
     'SUBTYPE_OF_DISALLOWED_TYPE',
     "Classes and mixins can't implement '{0}'.",
     correctionMessage:
-        "Try specifying a different interface, or remove the class from the list.",
+        "Try specifying a different interface, or remove the class from the "
+        "list.",
     hasPublishedDocs: true,
     uniqueName: 'IMPLEMENTS_DISALLOWED_CLASS',
   );
@@ -5841,7 +5947,8 @@
     'IMPLICIT_THIS_REFERENCE_IN_INITIALIZER',
     "The instance member '{0}' can't be accessed in an initializer.",
     correctionMessage:
-        "Try replacing the reference to the instance member with a different expression",
+        "Try replacing the reference to the instance member with a different "
+        "expression",
     hasPublishedDocs: true,
   );
 
@@ -5957,7 +6064,8 @@
     'INCONSISTENT_INHERITANCE',
     "Superinterfaces don't have a valid override for '{0}': {1}.",
     correctionMessage:
-        "Try adding an explicit override that is consistent with all of the inherited members.",
+        "Try adding an explicit override that is consistent with all of the "
+        "inherited members.",
     hasPublishedDocs: true,
   );
 
@@ -5976,9 +6084,11 @@
   static const CompileTimeErrorCode INCONSISTENT_INHERITANCE_GETTER_AND_METHOD =
       CompileTimeErrorCode(
     'INCONSISTENT_INHERITANCE_GETTER_AND_METHOD',
-    "'{0}' is inherited as a getter (from '{1}') and also a method (from '{2}').",
+    "'{0}' is inherited as a getter (from '{1}') and also a method (from "
+        "'{2}').",
     correctionMessage:
-        "Try adjusting the supertypes of this class to remove the inconsistency.",
+        "Try adjusting the supertypes of this class to remove the "
+        "inconsistency.",
   );
 
   /**
@@ -5992,7 +6102,8 @@
   static const CompileTimeErrorCode INCONSISTENT_LANGUAGE_VERSION_OVERRIDE =
       CompileTimeErrorCode(
     'INCONSISTENT_LANGUAGE_VERSION_OVERRIDE',
-    "Parts must have exactly the same language version override as the library.",
+    "Parts must have exactly the same language version override as the "
+        "library.",
   );
 
   /**
@@ -6051,7 +6162,8 @@
     'INITIALIZER_FOR_NON_EXISTENT_FIELD',
     "'{0}' isn't a field in the enclosing class.",
     correctionMessage:
-        "Try correcting the name to match an existing field, or defining a field named '{0}'.",
+        "Try correcting the name to match an existing field, or defining a "
+        "field named '{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -6114,7 +6226,8 @@
   static const CompileTimeErrorCode INITIALIZER_FOR_STATIC_FIELD =
       CompileTimeErrorCode(
     'INITIALIZER_FOR_STATIC_FIELD',
-    "'{0}' is a static field in the enclosing class. Fields initialized in a constructor can't be static.",
+    "'{0}' is a static field in the enclosing class. Fields initialized in a "
+        "constructor can't be static.",
     correctionMessage: "Try removing the initialization.",
     hasPublishedDocs: true,
   );
@@ -6199,7 +6312,8 @@
     'INITIALIZING_FORMAL_FOR_NON_EXISTENT_FIELD',
     "'{0}' isn't a field in the enclosing class.",
     correctionMessage:
-        "Try correcting the name to match an existing field, or defining a field named '{0}'.",
+        "Try correcting the name to match an existing field, or defining a "
+        "field named '{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -6372,7 +6486,8 @@
     'INSTANCE_MEMBER_ACCESS_FROM_STATIC',
     "Instance members can't be accessed from a static method.",
     correctionMessage:
-        "Try removing the reference to the instance member, or removing the keyword 'static' from the method.",
+        "Try removing the reference to the instance member, or removing the "
+        "keyword 'static' from the method.",
     hasPublishedDocs: true,
   );
 
@@ -6534,9 +6649,11 @@
   static const CompileTimeErrorCode INTEGER_LITERAL_IMPRECISE_AS_DOUBLE =
       CompileTimeErrorCode(
     'INTEGER_LITERAL_IMPRECISE_AS_DOUBLE',
-    "The integer literal is being used as a double, but can't be represented as a 64-bit double without overflow or loss of precision: '{0}'.",
+    "The integer literal is being used as a double, but can't be represented "
+        "as a 64-bit double without overflow or loss of precision: '{0}'.",
     correctionMessage:
-        "Try using the class 'BigInt', or switch to the closest valid double: '{1}'.",
+        "Try using the class 'BigInt', or switch to the closest valid double: "
+        "'{1}'.",
     hasPublishedDocs: true,
   );
 
@@ -6571,7 +6688,8 @@
     'INTEGER_LITERAL_OUT_OF_RANGE',
     "The integer literal {0} can't be represented in 64 bits.",
     correctionMessage:
-        "Try using the 'BigInt' class if you need an integer larger than 9,223,372,036,854,775,807 or less than -9,223,372,036,854,775,808.",
+        "Try using the 'BigInt' class if you need an integer larger than "
+        "9,223,372,036,854,775,807 or less than -9,223,372,036,854,775,808.",
     hasPublishedDocs: true,
   );
 
@@ -6646,7 +6764,8 @@
   // ```
   static const CompileTimeErrorCode INVALID_ANNOTATION = CompileTimeErrorCode(
     'INVALID_ANNOTATION',
-    "Annotation must be either a const variable reference or const constructor invocation.",
+    "Annotation must be either a const variable reference or const constructor "
+        "invocation.",
     hasPublishedDocs: true,
   );
 
@@ -6705,7 +6824,8 @@
     'INVALID_ANNOTATION_CONSTANT_VALUE_FROM_DEFERRED_LIBRARY',
     "Constant values from a deferred library can't be used in annotations.",
     correctionMessage:
-        "Try moving the constant from the deferred library, or removing 'deferred' from the import.",
+        "Try moving the constant from the deferred library, or removing "
+        "'deferred' from the import.",
     hasPublishedDocs: true,
   );
 
@@ -6759,7 +6879,8 @@
     'INVALID_ANNOTATION_FROM_DEFERRED_LIBRARY',
     "Constant values from a deferred library can't be used as annotations.",
     correctionMessage:
-        "Try removing the annotation, or changing the import to not be deferred.",
+        "Try removing the annotation, or changing the import to not be "
+        "deferred.",
     hasPublishedDocs: true,
   );
 
@@ -6809,7 +6930,8 @@
     'INVALID_ASSIGNMENT',
     "A value of type '{0}' can't be assigned to a variable of type '{1}'.",
     correctionMessage:
-        "Try changing the type of the variable, or casting the right-hand type to '{1}'.",
+        "Try changing the type of the variable, or casting the right-hand type "
+        "to '{1}'.",
     hasPublishedDocs: true,
   );
 
@@ -6821,7 +6943,8 @@
   static const CompileTimeErrorCode INVALID_CAST_FUNCTION =
       CompileTimeErrorCode(
     'INVALID_CAST_FUNCTION',
-    "The function '{0}' has type '{1}' that isn't of expected type '{2}'. This means its parameter or return type doesn't match what is expected.",
+    "The function '{0}' has type '{1}' that isn't of expected type '{2}'. This "
+        "means its parameter or return type doesn't match what is expected.",
   );
 
   /**
@@ -6832,7 +6955,9 @@
   static const CompileTimeErrorCode INVALID_CAST_FUNCTION_EXPR =
       CompileTimeErrorCode(
     'INVALID_CAST_FUNCTION_EXPR',
-    "The function expression type '{0}' isn't of type '{1}'. This means its parameter or return type doesn't match what is expected. Consider changing parameter type(s) or the returned type(s).",
+    "The function expression type '{0}' isn't of type '{1}'. This means its "
+        "parameter or return type doesn't match what is expected. Consider "
+        "changing parameter type(s) or the returned type(s).",
   );
 
   /**
@@ -6853,7 +6978,9 @@
   static const CompileTimeErrorCode INVALID_CAST_LITERAL_LIST =
       CompileTimeErrorCode(
     'INVALID_CAST_LITERAL_LIST',
-    "The list literal type '{0}' isn't of expected type '{1}'. The list's type can be changed with an explicit generic type argument or by changing the element types.",
+    "The list literal type '{0}' isn't of expected type '{1}'. The list's type "
+        "can be changed with an explicit generic type argument or by changing "
+        "the element types.",
   );
 
   /**
@@ -6864,7 +6991,9 @@
   static const CompileTimeErrorCode INVALID_CAST_LITERAL_MAP =
       CompileTimeErrorCode(
     'INVALID_CAST_LITERAL_MAP',
-    "The map literal type '{0}' isn't of expected type '{1}'. The maps's type can be changed with an explicit generic type arguments or by changing the key and value types.",
+    "The map literal type '{0}' isn't of expected type '{1}'. The maps's type "
+        "can be changed with an explicit generic type arguments or by changing "
+        "the key and value types.",
   );
 
   /**
@@ -6875,7 +7004,9 @@
   static const CompileTimeErrorCode INVALID_CAST_LITERAL_SET =
       CompileTimeErrorCode(
     'INVALID_CAST_LITERAL_SET',
-    "The set literal type '{0}' isn't of expected type '{1}'. The set's type can be changed with an explicit generic type argument or by changing the element types.",
+    "The set literal type '{0}' isn't of expected type '{1}'. The set's type "
+        "can be changed with an explicit generic type argument or by changing "
+        "the element types.",
   );
 
   /**
@@ -6885,7 +7016,9 @@
    */
   static const CompileTimeErrorCode INVALID_CAST_METHOD = CompileTimeErrorCode(
     'INVALID_CAST_METHOD',
-    "The method tear-off '{0}' has type '{1}' that isn't of expected type '{2}'. This means its parameter or return type doesn't match what is expected.",
+    "The method tear-off '{0}' has type '{1}' that isn't of expected type "
+        "'{2}'. This means its parameter or return type doesn't match what is "
+        "expected.",
   );
 
   /**
@@ -6974,7 +7107,8 @@
   static const CompileTimeErrorCode INVALID_EXTENSION_ARGUMENT_COUNT =
       CompileTimeErrorCode(
     'INVALID_EXTENSION_ARGUMENT_COUNT',
-    "Extension overrides must have exactly one argument: the value of 'this' in the extension method.",
+    "Extension overrides must have exactly one argument: the value of 'this' "
+        "in the extension method.",
     correctionMessage: "Try specifying exactly one argument.",
     hasPublishedDocs: true,
   );
@@ -7038,7 +7172,8 @@
   static const CompileTimeErrorCode INVALID_FACTORY_NAME_NOT_A_CLASS =
       CompileTimeErrorCode(
     'INVALID_FACTORY_NAME_NOT_A_CLASS',
-    "The name of a factory constructor must be the same as the name of the immediately enclosing class.",
+    "The name of a factory constructor must be the same as the name of the "
+        "immediately enclosing class.",
     hasPublishedDocs: true,
   );
 
@@ -7136,7 +7271,8 @@
   static const CompileTimeErrorCode INVALID_IMPLEMENTATION_OVERRIDE =
       CompileTimeErrorCode(
     'INVALID_IMPLEMENTATION_OVERRIDE',
-    "'{1}.{0}' ('{2}') isn't a valid concrete implementation of '{3}.{0}' ('{4}').",
+    "'{1}.{0}' ('{2}') isn't a valid concrete implementation of '{3}.{0}' "
+        "('{4}').",
     hasPublishedDocs: true,
   );
 
@@ -7169,9 +7305,11 @@
   static const CompileTimeErrorCode INVALID_INLINE_FUNCTION_TYPE =
       CompileTimeErrorCode(
     'INVALID_INLINE_FUNCTION_TYPE',
-    "Inline function types can't be used for parameters in a generic function type.",
+    "Inline function types can't be used for parameters in a generic function "
+        "type.",
     correctionMessage:
-        "Try using a generic function type (returnType 'Function(' parameters ')').",
+        "Try using a generic function type (returnType 'Function(' parameters "
+        "')').",
     hasPublishedDocs: true,
   );
 
@@ -7432,7 +7570,8 @@
   static const CompileTimeErrorCode INVALID_TYPE_ARGUMENT_IN_CONST_LIST =
       CompileTimeErrorCode(
     'INVALID_TYPE_ARGUMENT_IN_CONST_LITERAL',
-    "Constant list literals can't include a type parameter as a type argument, such as '{0}'.",
+    "Constant list literals can't include a type parameter as a type argument, "
+        "such as '{0}'.",
     correctionMessage:
         "Try replacing the type parameter with a different type.",
     hasPublishedDocs: true,
@@ -7446,7 +7585,8 @@
   static const CompileTimeErrorCode INVALID_TYPE_ARGUMENT_IN_CONST_MAP =
       CompileTimeErrorCode(
     'INVALID_TYPE_ARGUMENT_IN_CONST_LITERAL',
-    "Constant map literals can't include a type parameter as a type argument, such as '{0}'.",
+    "Constant map literals can't include a type parameter as a type argument, "
+        "such as '{0}'.",
     correctionMessage:
         "Try replacing the type parameter with a different type.",
     hasPublishedDocs: true,
@@ -7460,7 +7600,8 @@
   static const CompileTimeErrorCode INVALID_TYPE_ARGUMENT_IN_CONST_SET =
       CompileTimeErrorCode(
     'INVALID_TYPE_ARGUMENT_IN_CONST_LITERAL',
-    "Constant set literals can't include a type parameter as a type argument, such as '{0}'.",
+    "Constant set literals can't include a type parameter as a type argument, "
+        "such as '{0}'.",
     correctionMessage:
         "Try replacing the type parameter with a different type.",
     hasPublishedDocs: true,
@@ -7500,7 +7641,8 @@
   static const CompileTimeErrorCode INVALID_USE_OF_COVARIANT =
       CompileTimeErrorCode(
     'INVALID_USE_OF_COVARIANT',
-    "The 'covariant' keyword can only be used for parameters in instance methods or before non-final instance fields.",
+    "The 'covariant' keyword can only be used for parameters in instance "
+        "methods or before non-final instance fields.",
     correctionMessage: "Try removing the 'covariant' keyword.",
   );
 
@@ -7585,7 +7727,8 @@
   static const CompileTimeErrorCode INVOCATION_OF_EXTENSION_WITHOUT_CALL =
       CompileTimeErrorCode(
     'INVOCATION_OF_EXTENSION_WITHOUT_CALL',
-    "The extension '{0}' doesn't define a 'call' method so the override can't be used in an invocation.",
+    "The extension '{0}' doesn't define a 'call' method so the override can't "
+        "be used in an invocation.",
     hasPublishedDocs: true,
   );
 
@@ -7620,7 +7763,8 @@
     'INVOCATION_OF_NON_FUNCTION',
     "'{0}' isn't a function.",
     correctionMessage:
-        "Try correcting the name to match an existing function, or define a method or function named '{0}'.",
+        "Try correcting the name to match an existing function, or define a "
+        "method or function named '{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -7799,7 +7943,8 @@
     'LABEL_UNDEFINED',
     "Can't reference an undefined label '{0}'.",
     correctionMessage:
-        "Try defining the label, or correcting the name to match an existing label.",
+        "Try defining the label, or correcting the name to match an existing "
+        "label.",
     hasPublishedDocs: true,
   );
 
@@ -7850,9 +7995,11 @@
   static const CompileTimeErrorCode LATE_FINAL_FIELD_WITH_CONST_CONSTRUCTOR =
       CompileTimeErrorCode(
     'LATE_FINAL_FIELD_WITH_CONST_CONSTRUCTOR',
-    "Can't have a late final field in a class with a generative const constructor.",
+    "Can't have a late final field in a class with a generative const "
+        "constructor.",
     correctionMessage:
-        "Try removing the 'late' modifier, or don't declare 'const' constructors.",
+        "Try removing the 'late' modifier, or don't declare 'const' "
+        "constructors.",
     hasPublishedDocs: true,
   );
 
@@ -7996,7 +8143,8 @@
   static const CompileTimeErrorCode MAIN_FIRST_POSITIONAL_PARAMETER_TYPE =
       CompileTimeErrorCode(
     'MAIN_FIRST_POSITIONAL_PARAMETER_TYPE',
-    "The type of the first positional parameter of the 'main' function must be a supertype of 'List<String>'.",
+    "The type of the first positional parameter of the 'main' function must be "
+        "a supertype of 'List<String>'.",
     correctionMessage: "Try changing the type of the parameter.",
     hasPublishedDocs: true,
   );
@@ -8036,7 +8184,8 @@
     'MAIN_HAS_REQUIRED_NAMED_PARAMETERS',
     "The function 'main' can't have any required named parameters.",
     correctionMessage:
-        "Try using a different name for the function, or removing the 'required' modifier.",
+        "Try using a different name for the function, or removing the "
+        "'required' modifier.",
     hasPublishedDocs: true,
   );
 
@@ -8082,9 +8231,11 @@
   static const CompileTimeErrorCode
       MAIN_HAS_TOO_MANY_REQUIRED_POSITIONAL_PARAMETERS = CompileTimeErrorCode(
     'MAIN_HAS_TOO_MANY_REQUIRED_POSITIONAL_PARAMETERS',
-    "The function 'main' can't have more than two required positional parameters.",
+    "The function 'main' can't have more than two required positional "
+        "parameters.",
     correctionMessage:
-        "Try using a different name for the function, or removing extra parameters.",
+        "Try using a different name for the function, or removing extra "
+        "parameters.",
     hasPublishedDocs: true,
   );
 
@@ -8251,7 +8402,8 @@
   static const CompileTimeErrorCode MISSING_CONST_IN_LIST_LITERAL =
       CompileTimeErrorCode(
     'MISSING_CONST_IN_LIST_LITERAL',
-    "List literals must be prefixed with 'const' when used as a constant expression.",
+    "List literals must be prefixed with 'const' when used as a constant "
+        "expression.",
     correctionMessage: "Try adding the keyword 'const' before the literal.",
   );
 
@@ -8261,7 +8413,8 @@
   static const CompileTimeErrorCode MISSING_CONST_IN_MAP_LITERAL =
       CompileTimeErrorCode(
     'MISSING_CONST_IN_MAP_LITERAL',
-    "Map literals must be prefixed with 'const' when used as a constant expression.",
+    "Map literals must be prefixed with 'const' when used as a constant "
+        "expression.",
     correctionMessage: "Try adding the keyword 'const' before the literal.",
   );
 
@@ -8271,7 +8424,8 @@
   static const CompileTimeErrorCode MISSING_CONST_IN_SET_LITERAL =
       CompileTimeErrorCode(
     'MISSING_CONST_IN_SET_LITERAL',
-    "Set literals must be prefixed with 'const' when used as a constant expression.",
+    "Set literals must be prefixed with 'const' when used as a constant "
+        "expression.",
     correctionMessage: "Try adding the keyword 'const' before the literal.",
   );
 
@@ -8347,9 +8501,11 @@
   static const CompileTimeErrorCode MISSING_DEFAULT_VALUE_FOR_PARAMETER =
       CompileTimeErrorCode(
     'MISSING_DEFAULT_VALUE_FOR_PARAMETER',
-    "The parameter '{0}' can't have a value of 'null' because of its type, but the implicit default value is 'null'.",
+    "The parameter '{0}' can't have a value of 'null' because of its type, but "
+        "the implicit default value is 'null'.",
     correctionMessage:
-        "Try adding either an explicit non-'null' default value or the 'required' modifier.",
+        "Try adding either an explicit non-'null' default value or the "
+        "'required' modifier.",
     hasPublishedDocs: true,
   );
 
@@ -8387,7 +8543,8 @@
   static const CompileTimeErrorCode MISSING_REQUIRED_ARGUMENT =
       CompileTimeErrorCode(
     'MISSING_REQUIRED_ARGUMENT',
-    "The named parameter '{0}' is required, but there's no corresponding argument.",
+    "The named parameter '{0}' is required, but there's no corresponding "
+        "argument.",
     correctionMessage: "Try adding the required argument.",
     hasPublishedDocs: true,
   );
@@ -8510,7 +8667,8 @@
       MIXIN_APPLICATION_CONCRETE_SUPER_INVOKED_MEMBER_TYPE =
       CompileTimeErrorCode(
     'MIXIN_APPLICATION_CONCRETE_SUPER_INVOKED_MEMBER_TYPE',
-    "The super-invoked member '{0}' has the type '{1}', and the concrete member in the class has the type '{2}'.",
+    "The super-invoked member '{0}' has the type '{1}', and the concrete "
+        "member in the class has the type '{2}'.",
     hasPublishedDocs: true,
   );
 
@@ -8634,7 +8792,8 @@
   static const CompileTimeErrorCode
       MIXIN_APPLICATION_NO_CONCRETE_SUPER_INVOKED_MEMBER = CompileTimeErrorCode(
     'MIXIN_APPLICATION_NO_CONCRETE_SUPER_INVOKED_MEMBER',
-    "The class doesn't have a concrete implementation of the super-invoked member '{0}'.",
+    "The class doesn't have a concrete implementation of the super-invoked "
+        "member '{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -8694,7 +8853,8 @@
   static const CompileTimeErrorCode MIXIN_CLASS_DECLARES_CONSTRUCTOR =
       CompileTimeErrorCode(
     'MIXIN_CLASS_DECLARES_CONSTRUCTOR',
-    "The class '{0}' can't be used as a mixin because it declares a constructor.",
+    "The class '{0}' can't be used as a mixin because it declares a "
+        "constructor.",
     hasPublishedDocs: true,
   );
 
@@ -8722,19 +8882,24 @@
   static const CompileTimeErrorCode
       MIXIN_INFERENCE_INCONSISTENT_MATCHING_CLASSES = CompileTimeErrorCode(
     'MIXIN_INFERENCE_INCONSISTENT_MATCHING_CLASSES',
-    "Type parameters couldn't be inferred for the mixin '{0}' because the base class implements the mixin's supertype constraint '{1}' in multiple conflicting ways",
+    "Type parameters couldn't be inferred for the mixin '{0}' because the base "
+        "class implements the mixin's supertype constraint '{1}' in multiple "
+        "conflicting ways",
   );
 
   static const CompileTimeErrorCode MIXIN_INFERENCE_NO_MATCHING_CLASS =
       CompileTimeErrorCode(
     'MIXIN_INFERENCE_NO_MATCHING_CLASS',
-    "Type parameters couldn't be inferred for the mixin '{0}' because the base class doesn't implement the mixin's supertype constraint '{1}'",
+    "Type parameters couldn't be inferred for the mixin '{0}' because the base "
+        "class doesn't implement the mixin's supertype constraint '{1}'",
   );
 
   static const CompileTimeErrorCode MIXIN_INFERENCE_NO_POSSIBLE_SUBSTITUTION =
       CompileTimeErrorCode(
     'MIXIN_INFERENCE_NO_POSSIBLE_SUBSTITUTION',
-    "Type parameters couldn't be inferred for the mixin '{0}' because no type parameter substitution could be found matching the mixin's supertype constraints",
+    "Type parameters couldn't be inferred for the mixin '{0}' because no type "
+        "parameter substitution could be found matching the mixin's supertype "
+        "constraints",
   );
 
   /**
@@ -8798,7 +8963,8 @@
   static const CompileTimeErrorCode MIXIN_INHERITS_FROM_NOT_OBJECT =
       CompileTimeErrorCode(
     'MIXIN_INHERITS_FROM_NOT_OBJECT',
-    "The class '{0}' can't be used as a mixin because it extends a class other than 'Object'.",
+    "The class '{0}' can't be used as a mixin because it extends a class other "
+        "than 'Object'.",
     hasPublishedDocs: true,
   );
 
@@ -8839,7 +9005,8 @@
     'SUBTYPE_OF_DISALLOWED_TYPE',
     "Classes can't mixin '{0}'.",
     correctionMessage:
-        "Try specifying a different class or mixin, or remove the class or mixin from the list.",
+        "Try specifying a different class or mixin, or remove the class or "
+        "mixin from the list.",
     hasPublishedDocs: true,
     uniqueName: 'MIXIN_OF_DISALLOWED_CLASS',
   );
@@ -8896,7 +9063,8 @@
   static const CompileTimeErrorCode
       MIXIN_ON_TYPE_ALIAS_EXPANDS_TO_TYPE_PARAMETER = CompileTimeErrorCode(
     'SUPERTYPE_EXPANDS_TO_TYPE_PARAMETER',
-    "A type alias that expands to a type parameter can't be used as a superclass constraint.",
+    "A type alias that expands to a type parameter can't be used as a "
+        "superclass constraint.",
     hasPublishedDocs: true,
     uniqueName: 'MIXIN_ON_TYPE_ALIAS_EXPANDS_TO_TYPE_PARAMETER',
   );
@@ -8920,7 +9088,8 @@
     'SUBTYPE_OF_DISALLOWED_TYPE',
     "''{0}' can't be used as a superclass constraint.",
     correctionMessage:
-        "Try specifying a different super-class constraint, or remove the 'on' clause.",
+        "Try specifying a different super-class constraint, or remove the 'on' "
+        "clause.",
     hasPublishedDocs: true,
     uniqueName: 'MIXIN_SUPER_CLASS_CONSTRAINT_DISALLOWED_CLASS',
   );
@@ -9142,7 +9311,8 @@
     'NEW_WITH_UNDEFINED_CONSTRUCTOR',
     "The class '{0}' doesn't have a constructor named '{1}'.",
     correctionMessage:
-        "Try invoking a different constructor, or define a constructor named '{1}'.",
+        "Try invoking a different constructor, or define a constructor named "
+        "'{1}'.",
   );
 
   /**
@@ -9212,7 +9382,8 @@
       NON_ABSTRACT_CLASS_INHERITS_ABSTRACT_MEMBER_FIVE_PLUS =
       CompileTimeErrorCode(
     'NON_ABSTRACT_CLASS_INHERITS_ABSTRACT_MEMBER',
-    "Missing concrete implementations of '{0}', '{1}', '{2}', '{3}', and {4} more.",
+    "Missing concrete implementations of '{0}', '{1}', '{2}', '{3}', and {4} "
+        "more.",
     correctionMessage:
         "Try implementing the missing methods, or make the class abstract.",
     hasPublishedDocs: true,
@@ -9655,9 +9826,11 @@
   static const CompileTimeErrorCode
       NON_CONSTANT_CASE_EXPRESSION_FROM_DEFERRED_LIBRARY = CompileTimeErrorCode(
     'NON_CONSTANT_CASE_EXPRESSION_FROM_DEFERRED_LIBRARY',
-    "Constant values from a deferred library can't be used as a case expression.",
+    "Constant values from a deferred library can't be used as a case "
+        "expression.",
     correctionMessage:
-        "Try re-writing the switch as a series of if statements, or changing the import to not be deferred.",
+        "Try re-writing the switch as a series of if statements, or changing "
+        "the import to not be deferred.",
     hasPublishedDocs: true,
   );
 
@@ -9761,9 +9934,11 @@
   static const CompileTimeErrorCode
       NON_CONSTANT_DEFAULT_VALUE_FROM_DEFERRED_LIBRARY = CompileTimeErrorCode(
     'NON_CONSTANT_DEFAULT_VALUE_FROM_DEFERRED_LIBRARY',
-    "Constant values from a deferred library can't be used as a default parameter value.",
+    "Constant values from a deferred library can't be used as a default "
+        "parameter value.",
     correctionMessage:
-        "Try leaving the default as null and initializing the parameter inside the function body.",
+        "Try leaving the default as null and initializing the parameter inside "
+        "the function body.",
     hasPublishedDocs: true,
   );
 
@@ -9878,9 +10053,11 @@
   static const CompileTimeErrorCode
       NON_CONSTANT_LIST_ELEMENT_FROM_DEFERRED_LIBRARY = CompileTimeErrorCode(
     'COLLECTION_ELEMENT_FROM_DEFERRED_LIBRARY',
-    "Constant values from a deferred library can't be used as values in a 'const' list literal.",
+    "Constant values from a deferred library can't be used as values in a "
+        "'const' list literal.",
     correctionMessage:
-        "Try removing the keyword 'const' from the list literal or removing the keyword 'deferred' from the import.",
+        "Try removing the keyword 'const' from the list literal or removing "
+        "the keyword 'deferred' from the import.",
     hasPublishedDocs: true,
     uniqueName: 'NON_CONSTANT_LIST_ELEMENT_FROM_DEFERRED_LIBRARY',
   );
@@ -9983,9 +10160,11 @@
   static const CompileTimeErrorCode NON_CONSTANT_MAP_KEY_FROM_DEFERRED_LIBRARY =
       CompileTimeErrorCode(
     'COLLECTION_ELEMENT_FROM_DEFERRED_LIBRARY',
-    "Constant values from a deferred library can't be used as keys in a 'const' map literal.",
+    "Constant values from a deferred library can't be used as keys in a "
+        "'const' map literal.",
     correctionMessage:
-        "Try removing the keyword 'const' from the map literal or removing the keyword 'deferred' from the import.",
+        "Try removing the keyword 'const' from the map literal or removing the "
+        "keyword 'deferred' from the import.",
     hasPublishedDocs: true,
     uniqueName: 'NON_CONSTANT_MAP_KEY_FROM_DEFERRED_LIBRARY',
   );
@@ -10037,9 +10216,11 @@
   static const CompileTimeErrorCode
       NON_CONSTANT_MAP_VALUE_FROM_DEFERRED_LIBRARY = CompileTimeErrorCode(
     'COLLECTION_ELEMENT_FROM_DEFERRED_LIBRARY',
-    "Constant values from a deferred library can't be used as values in a 'const' map literal.",
+    "Constant values from a deferred library can't be used as values in a "
+        "'const' map literal.",
     correctionMessage:
-        "Try removing the keyword 'const' from the map literal or removing the keyword 'deferred' from the import.",
+        "Try removing the keyword 'const' from the map literal or removing the "
+        "keyword 'deferred' from the import.",
     hasPublishedDocs: true,
     uniqueName: 'NON_CONSTANT_MAP_VALUE_FROM_DEFERRED_LIBRARY',
   );
@@ -10095,7 +10276,8 @@
   static const CompileTimeErrorCode NON_CONST_MAP_AS_EXPRESSION_STATEMENT =
       CompileTimeErrorCode(
     'NON_CONST_MAP_AS_EXPRESSION_STATEMENT',
-    "A non-constant map or set literal without type arguments can't be used as an expression statement.",
+    "A non-constant map or set literal without type arguments can't be used as "
+        "an expression statement.",
   );
 
   /**
@@ -10147,7 +10329,8 @@
     'NON_GENERATIVE_CONSTRUCTOR',
     "The generative constructor '{0}' is expected, but a factory was found.",
     correctionMessage:
-        "Try calling a different constructor of the superclass, or making the called constructor not be a factory constructor.",
+        "Try calling a different constructor of the superclass, or making the "
+        "called constructor not be a factory constructor.",
     hasPublishedDocs: true,
   );
 
@@ -10164,9 +10347,13 @@
   static const CompileTimeErrorCode NON_GENERATIVE_IMPLICIT_CONSTRUCTOR =
       CompileTimeErrorCode(
     'NON_GENERATIVE_IMPLICIT_CONSTRUCTOR',
-    "The unnamed constructor of superclass '{0}' (called by the default constructor of '{1}') must be a generative constructor, but factory found.",
+    "The unnamed constructor of superclass '{0}' (called by the default "
+        "constructor of '{1}') must be a generative constructor, but factory "
+        "found.",
     correctionMessage:
-        "Try adding an explicit constructor that has a different superinitializer or changing the superclass constructor '{2}' to not be a factory constructor.",
+        "Try adding an explicit constructor that has a different "
+        "superinitializer or changing the superclass constructor '{2}' to not "
+        "be a factory constructor.",
   );
 
   /**
@@ -10256,7 +10443,8 @@
     'NON_TYPE_AS_TYPE_ARGUMENT',
     "The name '{0}' isn't a type so it can't be used as a type argument.",
     correctionMessage:
-        "Try correcting the name to an existing type, or defining a type named '{0}'.",
+        "Try correcting the name to an existing type, or defining a type named "
+        "'{0}'.",
     hasPublishedDocs: true,
     isUnresolvedIdentifier: true,
   );
@@ -10377,7 +10565,8 @@
     'NON_VOID_RETURN_FOR_SETTER',
     "The return type of the setter must be 'void' or absent.",
     correctionMessage:
-        "Try removing the return type, or define a method rather than a setter.",
+        "Try removing the return type, or define a method rather than a "
+        "setter.",
     hasPublishedDocs: true,
   );
 
@@ -10498,9 +10687,11 @@
       NOT_ASSIGNED_POTENTIALLY_NON_NULLABLE_LOCAL_VARIABLE =
       CompileTimeErrorCode(
     'NOT_ASSIGNED_POTENTIALLY_NON_NULLABLE_LOCAL_VARIABLE',
-    "The non-nullable local variable '{0}' must be assigned before it can be used.",
+    "The non-nullable local variable '{0}' must be assigned before it can be "
+        "used.",
     correctionMessage:
-        "Try giving it an initializer expression, or ensure that it's assigned on every execution path.",
+        "Try giving it an initializer expression, or ensure that it's assigned "
+        "on every execution path.",
     hasPublishedDocs: true,
   );
 
@@ -10680,7 +10871,8 @@
     'NOT_INITIALIZED_NON_NULLABLE_INSTANCE_FIELD',
     "Non-nullable instance field '{0}' must be initialized.",
     correctionMessage:
-        "Try adding an initializer expression, or a generative constructor that initializes it, or mark it 'late'.",
+        "Try adding an initializer expression, or a generative constructor "
+        "that initializes it, or mark it 'late'.",
     hasPublishedDocs: true,
   );
 
@@ -10694,7 +10886,8 @@
     'NOT_INITIALIZED_NON_NULLABLE_INSTANCE_FIELD',
     "Non-nullable instance field '{0}' must be initialized.",
     correctionMessage:
-        "Try adding an initializer expression, or add a field initializer in this constructor, or mark it 'late'.",
+        "Try adding an initializer expression, or add a field initializer in "
+        "this constructor, or mark it 'late'.",
     hasPublishedDocs: true,
     uniqueName: 'NOT_INITIALIZED_NON_NULLABLE_INSTANCE_FIELD_CONSTRUCTOR',
   );
@@ -10954,7 +11147,8 @@
     'NO_COMBINED_SUPER_SIGNATURE',
     "Can't infer missing types in '{0}' from overridden methods: {1}.",
     correctionMessage:
-        "Try providing explicit types for this method's parameters and return type.",
+        "Try providing explicit types for this method's parameters and return "
+        "type.",
     hasPublishedDocs: true,
   );
 
@@ -10968,7 +11162,8 @@
     'NO_DEFAULT_SUPER_CONSTRUCTOR',
     "The superclass '{0}' doesn't have a zero argument constructor.",
     correctionMessage:
-        "Try declaring a zero argument constructor in '{0}', or explicitly invoking a different constructor in '{0}'.",
+        "Try declaring a zero argument constructor in '{0}', or explicitly "
+        "invoking a different constructor in '{0}'.",
     uniqueName: 'NO_DEFAULT_SUPER_CONSTRUCTOR_EXPLICIT',
   );
 
@@ -10983,7 +11178,8 @@
     'NO_DEFAULT_SUPER_CONSTRUCTOR',
     "The superclass '{0}' doesn't have a zero argument constructor.",
     correctionMessage:
-        "Try declaring a zero argument constructor in '{0}', or declaring a constructor in {1} that explicitly invokes a constructor in '{0}'.",
+        "Try declaring a zero argument constructor in '{0}', or declaring a "
+        "constructor in {1} that explicitly invokes a constructor in '{0}'.",
     uniqueName: 'NO_DEFAULT_SUPER_CONSTRUCTOR_IMPLICIT',
   );
 
@@ -10999,9 +11195,13 @@
   static const CompileTimeErrorCode NO_GENERATIVE_CONSTRUCTORS_IN_SUPERCLASS =
       CompileTimeErrorCode(
     'NO_GENERATIVE_CONSTRUCTORS_IN_SUPERCLASS',
-    "The class '{0}' cannot extend '{1}' because '{1}' only has factory constructors (no generative constructors), and '{0}' has at least one generative constructor.",
+    "The class '{0}' cannot extend '{1}' because '{1}' only has factory "
+        "constructors (no generative constructors), and '{0}' has at least one "
+        "generative constructor.",
     correctionMessage:
-        "Try implementing the class instead, adding a generative (not factory) constructor to the superclass {0}, or a factory constructor to the subclass.",
+        "Try implementing the class instead, adding a generative (not factory) "
+        "constructor to the superclass {0}, or a factory constructor to the "
+        "subclass.",
   );
 
   /**
@@ -11311,7 +11511,8 @@
     'PART_OF_DIFFERENT_LIBRARY',
     "Expected this library to be part of '{0}', not '{1}'.",
     correctionMessage:
-        "Try including a different part, or changing the name of the library in the part's part-of directive.",
+        "Try including a different part, or changing the name of the library "
+        "in the part's part-of directive.",
     hasPublishedDocs: true,
   );
 
@@ -11404,9 +11605,11 @@
   static const CompileTimeErrorCode PART_OF_UNNAMED_LIBRARY =
       CompileTimeErrorCode(
     'PART_OF_UNNAMED_LIBRARY',
-    "The library is unnamed. A URI is expected, not a library name '{0}', in the part-of directive.",
+    "The library is unnamed. A URI is expected, not a library name '{0}', in "
+        "the part-of directive.",
     correctionMessage:
-        "Try changing the part-of directive to a URI, or try including a different part.",
+        "Try changing the part-of directive to a URI, or try including a "
+        "different part.",
     hasPublishedDocs: true,
   );
 
@@ -11452,7 +11655,8 @@
   static const CompileTimeErrorCode PREFIX_COLLIDES_WITH_TOP_LEVEL_MEMBER =
       CompileTimeErrorCode(
     'PREFIX_COLLIDES_WITH_TOP_LEVEL_MEMBER',
-    "The name '{0}' is already used as an import prefix and can't be used to name a top-level element.",
+    "The name '{0}' is already used as an import prefix and can't be used to "
+        "name a top-level element.",
     correctionMessage:
         "Try renaming either the top-level element or the prefix.",
     hasPublishedDocs: true,
@@ -11501,7 +11705,8 @@
     'PREFIX_IDENTIFIER_NOT_FOLLOWED_BY_DOT',
     "The name '{0}' refers to an import prefix, so it must be followed by '.'.",
     correctionMessage:
-        "Try correcting the name to refer to something other than a prefix, or renaming the prefix.",
+        "Try correcting the name to refer to something other than a prefix, or "
+        "renaming the prefix.",
     hasPublishedDocs: true,
   );
 
@@ -11518,7 +11723,8 @@
   static const CompileTimeErrorCode PREFIX_SHADOWED_BY_LOCAL_DECLARATION =
       CompileTimeErrorCode(
     'PREFIX_SHADOWED_BY_LOCAL_DECLARATION',
-    "The prefix '{0}' can't be used here because it is shadowed by a local declaration.",
+    "The prefix '{0}' can't be used here because it is shadowed by a local "
+        "declaration.",
     correctionMessage:
         "Try renaming either the prefix or the local declaration.",
   );
@@ -11575,7 +11781,8 @@
   static const CompileTimeErrorCode PRIVATE_COLLISION_IN_MIXIN_APPLICATION =
       CompileTimeErrorCode(
     'PRIVATE_COLLISION_IN_MIXIN_APPLICATION',
-    "The private name '{0}', defined by '{1}', conflicts with the same name defined by '{2}'.",
+    "The private name '{0}', defined by '{1}', conflicts with the same name "
+        "defined by '{2}'.",
     correctionMessage: "Try removing '{1}' from the 'with' clause.",
     hasPublishedDocs: true,
   );
@@ -11617,14 +11824,16 @@
 
   static const CompileTimeErrorCode PRIVATE_SETTER = CompileTimeErrorCode(
     'PRIVATE_SETTER',
-    "The setter '{0}' is private and can't be accessed outside of the library that declares it.",
+    "The setter '{0}' is private and can't be accessed outside of the library "
+        "that declares it.",
     correctionMessage: "Try making it public.",
   );
 
   static const CompileTimeErrorCode READ_POTENTIALLY_UNASSIGNED_FINAL =
       CompileTimeErrorCode(
     'READ_POTENTIALLY_UNASSIGNED_FINAL',
-    "The final variable '{0}' can't be read because it is potentially unassigned at this point.",
+    "The final variable '{0}' can't be read because it is potentially "
+        "unassigned at this point.",
     correctionMessage:
         "Ensure that it is assigned on necessary execution paths.",
   );
@@ -11927,7 +12136,8 @@
     'REDIRECT_GENERATIVE_TO_MISSING_CONSTRUCTOR',
     "The constructor '{0}' couldn't be found in '{1}'.",
     correctionMessage:
-        "Try redirecting to a different constructor, or defining the constructor named '{0}'.",
+        "Try redirecting to a different constructor, or defining the "
+        "constructor named '{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -11987,7 +12197,8 @@
   static const CompileTimeErrorCode REDIRECT_TO_ABSTRACT_CLASS_CONSTRUCTOR =
       CompileTimeErrorCode(
     'REDIRECT_TO_ABSTRACT_CLASS_CONSTRUCTOR',
-    "The redirecting constructor '{0}' can't redirect to a constructor of the abstract class '{1}'.",
+    "The redirecting constructor '{0}' can't redirect to a constructor of the "
+        "abstract class '{1}'.",
     correctionMessage: "Try redirecting to a constructor of a different class.",
   );
 
@@ -12128,7 +12339,8 @@
   static const CompileTimeErrorCode REDIRECT_TO_INVALID_RETURN_TYPE =
       CompileTimeErrorCode(
     'REDIRECT_TO_INVALID_RETURN_TYPE',
-    "The return type '{0}' of the redirected constructor isn't a subtype of '{1}'.",
+    "The return type '{0}' of the redirected constructor isn't a subtype of "
+        "'{1}'.",
     correctionMessage: "Try redirecting to a different constructor.",
     hasPublishedDocs: true,
   );
@@ -12142,7 +12354,8 @@
     'REDIRECT_TO_MISSING_CONSTRUCTOR',
     "The constructor '{0}' couldn't be found in '{1}'.",
     correctionMessage:
-        "Try redirecting to a different constructor, or define the constructor named '{0}'.",
+        "Try redirecting to a different constructor, or define the constructor "
+        "named '{0}'.",
   );
 
   /**
@@ -12189,7 +12402,8 @@
   static const CompileTimeErrorCode REDIRECT_TO_NON_CLASS =
       CompileTimeErrorCode(
     'REDIRECT_TO_NON_CLASS',
-    "The name '{0}' isn't a type and can't be used in a redirected constructor.",
+    "The name '{0}' isn't a type and can't be used in a redirected "
+        "constructor.",
     correctionMessage: "Try redirecting to a different constructor.",
     hasPublishedDocs: true,
   );
@@ -12238,7 +12452,8 @@
   static const CompileTimeErrorCode REDIRECT_TO_NON_CONST_CONSTRUCTOR =
       CompileTimeErrorCode(
     'REDIRECT_TO_NON_CONST_CONSTRUCTOR',
-    "A constant redirecting constructor can't redirect to a non-constant constructor.",
+    "A constant redirecting constructor can't redirect to a non-constant "
+        "constructor.",
     correctionMessage: "Try redirecting to a different constructor.",
     hasPublishedDocs: true,
   );
@@ -12284,7 +12499,8 @@
   static const CompileTimeErrorCode
       REDIRECT_TO_TYPE_ALIAS_EXPANDS_TO_TYPE_PARAMETER = CompileTimeErrorCode(
     'REDIRECT_TO_TYPE_ALIAS_EXPANDS_TO_TYPE_PARAMETER',
-    "A redirecting constructor can't redirect to a type alias that expands to a type parameter.",
+    "A redirecting constructor can't redirect to a type alias that expands to "
+        "a type parameter.",
     correctionMessage: "Try replacing it with a class.",
     hasPublishedDocs: true,
   );
@@ -12345,7 +12561,9 @@
     'REFERENCED_BEFORE_DECLARATION',
     "Local variable '{0}' can't be referenced before it is declared.",
     correctionMessage:
-        "Try moving the declaration to before the first use, or renaming the local variable so that it doesn't hide a name from an enclosing scope.",
+        "Try moving the declaration to before the first use, or renaming the "
+        "local variable so that it doesn't hide a name from an enclosing "
+        "scope.",
     hasPublishedDocs: true,
   );
 
@@ -12398,7 +12616,8 @@
     'RETHROW_OUTSIDE_CATCH',
     "A rethrow must be inside of a catch clause.",
     correctionMessage:
-        "Try moving the expression into a catch clause, or using a 'throw' expression.",
+        "Try moving the expression into a catch clause, or using a 'throw' "
+        "expression.",
     hasPublishedDocs: true,
   );
 
@@ -12517,9 +12736,11 @@
   // ```
   static const CompileTimeErrorCode RETURN_IN_GENERATOR = CompileTimeErrorCode(
     'RETURN_IN_GENERATOR',
-    "Can't return a value from a generator function that uses the 'async*' or 'sync*' modifier.",
+    "Can't return a value from a generator function that uses the 'async*' or "
+        "'sync*' modifier.",
     correctionMessage:
-        "Try replacing 'return' with 'yield', using a block function body, or changing the method body modifier.",
+        "Try replacing 'return' with 'yield', using a block function body, or "
+        "changing the method body modifier.",
     hasPublishedDocs: true,
   );
 
@@ -12555,7 +12776,8 @@
   static const CompileTimeErrorCode RETURN_OF_INVALID_TYPE_FROM_CLOSURE =
       CompileTimeErrorCode(
     'RETURN_OF_INVALID_TYPE_FROM_CLOSURE',
-    "The return type '{0}' isn't a '{1}', as required by the closure's context.",
+    "The return type '{0}' isn't a '{1}', as required by the closure's "
+        "context.",
     hasPublishedDocs: true,
   );
 
@@ -12568,7 +12790,8 @@
   static const CompileTimeErrorCode RETURN_OF_INVALID_TYPE_FROM_CONSTRUCTOR =
       CompileTimeErrorCode(
     'RETURN_OF_INVALID_TYPE',
-    "A value of type '{0}' can't be returned from the constructor '{2}' because it has a return type of '{1}'.",
+    "A value of type '{0}' can't be returned from the constructor '{2}' "
+        "because it has a return type of '{1}'.",
     hasPublishedDocs: true,
     uniqueName: 'RETURN_OF_INVALID_TYPE_FROM_CONSTRUCTOR',
   );
@@ -12610,7 +12833,8 @@
   static const CompileTimeErrorCode RETURN_OF_INVALID_TYPE_FROM_FUNCTION =
       CompileTimeErrorCode(
     'RETURN_OF_INVALID_TYPE',
-    "A value of type '{0}' can't be returned from the function '{2}' because it has a return type of '{1}'.",
+    "A value of type '{0}' can't be returned from the function '{2}' because "
+        "it has a return type of '{1}'.",
     hasPublishedDocs: true,
     uniqueName: 'RETURN_OF_INVALID_TYPE_FROM_FUNCTION',
   );
@@ -12624,7 +12848,8 @@
   static const CompileTimeErrorCode RETURN_OF_INVALID_TYPE_FROM_METHOD =
       CompileTimeErrorCode(
     'RETURN_OF_INVALID_TYPE',
-    "A value of type '{0}' can't be returned from the method '{2}' because it has a return type of '{1}'.",
+    "A value of type '{0}' can't be returned from the method '{2}' because it "
+        "has a return type of '{1}'.",
     hasPublishedDocs: true,
     uniqueName: 'RETURN_OF_INVALID_TYPE_FROM_METHOD',
   );
@@ -12669,9 +12894,11 @@
   static const CompileTimeErrorCode SET_ELEMENT_FROM_DEFERRED_LIBRARY =
       CompileTimeErrorCode(
     'COLLECTION_ELEMENT_FROM_DEFERRED_LIBRARY',
-    "Constant values from a deferred library can't be used as values in a 'const' set literal.",
+    "Constant values from a deferred library can't be used as values in a "
+        "'const' set literal.",
     correctionMessage:
-        "Try removing the keyword 'const' from the set literal or removing the keyword 'deferred' from the import.",
+        "Try removing the keyword 'const' from the set literal or removing the "
+        "keyword 'deferred' from the import.",
     hasPublishedDocs: true,
     uniqueName: 'SET_ELEMENT_FROM_DEFERRED_LIBRARY',
   );
@@ -12769,7 +12996,8 @@
   static const CompileTimeErrorCode SPREAD_EXPRESSION_FROM_DEFERRED_LIBRARY =
       CompileTimeErrorCode(
     'SPREAD_EXPRESSION_FROM_DEFERRED_LIBRARY',
-    "Constant values from a deferred library can't be spread into a const literal.",
+    "Constant values from a deferred library can't be spread into a const "
+        "literal.",
     correctionMessage: "Try making the deferred import non-deferred.",
   );
 
@@ -12923,7 +13151,8 @@
   // ```
   static const CompileTimeErrorCode SUPER_IN_EXTENSION = CompileTimeErrorCode(
     'SUPER_IN_EXTENSION',
-    "The 'super' keyword can't be used in an extension because an extension doesn't have a superclass.",
+    "The 'super' keyword can't be used in an extension because an extension "
+        "doesn't have a superclass.",
     hasPublishedDocs: true,
   );
 
@@ -13065,7 +13294,8 @@
   static const CompileTimeErrorCode SWITCH_EXPRESSION_NOT_ASSIGNABLE =
       CompileTimeErrorCode(
     'SWITCH_EXPRESSION_NOT_ASSIGNABLE',
-    "Type '{0}' of the switch expression isn't assignable to the type '{1}' of case expressions.",
+    "Type '{0}' of the switch expression isn't assignable to the type '{1}' of "
+        "case expressions.",
     hasPublishedDocs: true,
   );
 
@@ -13103,7 +13333,8 @@
     'TEAROFF_OF_GENERATIVE_CONSTRUCTOR_OF_ABSTRACT_CLASS',
     "A generative constructor of an abstract class can't be torn off.",
     correctionMessage:
-        "Try tearing off a constructor of a concrete class, or a non-generative constructor.",
+        "Try tearing off a constructor of a concrete class, or a "
+        "non-generative constructor.",
     hasPublishedDocs: true,
   );
 
@@ -13190,9 +13421,11 @@
   // before any of the variables in the cycle are referenced.
   static const CompileTimeErrorCode TOP_LEVEL_CYCLE = CompileTimeErrorCode(
     'TOP_LEVEL_CYCLE',
-    "The type of '{0}' can't be inferred because it depends on itself through the cycle: {1}.",
+    "The type of '{0}' can't be inferred because it depends on itself through "
+        "the cycle: {1}.",
     correctionMessage:
-        "Try adding an explicit type to one or more of the variables in the cycle in order to break the cycle.",
+        "Try adding an explicit type to one or more of the variables in the "
+        "cycle in order to break the cycle.",
     hasPublishedDocs: true,
   );
 
@@ -13226,7 +13459,8 @@
   static const CompileTimeErrorCode TYPE_ALIAS_CANNOT_REFERENCE_ITSELF =
       CompileTimeErrorCode(
     'TYPE_ALIAS_CANNOT_REFERENCE_ITSELF',
-    "Typedefs can't reference themselves directly or recursively via another typedef.",
+    "Typedefs can't reference themselves directly or recursively via another "
+        "typedef.",
     hasPublishedDocs: true,
   );
 
@@ -13273,9 +13507,11 @@
   static const CompileTimeErrorCode TYPE_ANNOTATION_DEFERRED_CLASS =
       CompileTimeErrorCode(
     'TYPE_ANNOTATION_DEFERRED_CLASS',
-    "The deferred type '{0}' can't be used in a declaration, cast, or type test.",
+    "The deferred type '{0}' can't be used in a declaration, cast, or type "
+        "test.",
     correctionMessage:
-        "Try using a different type, or changing the import to not be deferred.",
+        "Try using a different type, or changing the import to not be "
+        "deferred.",
     hasPublishedDocs: true,
   );
 
@@ -13364,7 +13600,8 @@
     'TYPE_PARAMETER_REFERENCED_BY_STATIC',
     "Static members can't reference type parameters of the class.",
     correctionMessage:
-        "Try removing the reference to the type parameter, or making the member an instance member.",
+        "Try removing the reference to the type parameter, or making the "
+        "member an instance member.",
     hasPublishedDocs: true,
   );
 
@@ -13517,7 +13754,8 @@
     'TYPE_TEST_WITH_UNDEFINED_NAME',
     "The name '{0}' isn't defined, so it can't be used in an 'is' expression.",
     correctionMessage:
-        "Try changing the name to the name of an existing type, or creating a type with the name '{0}'.",
+        "Try changing the name to the name of an existing type, or creating a "
+        "type with the name '{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -13533,9 +13771,11 @@
   static const CompileTimeErrorCode
       UNCHECKED_METHOD_INVOCATION_OF_NULLABLE_VALUE = CompileTimeErrorCode(
     'UNCHECKED_USE_OF_NULLABLE_VALUE',
-    "The method '{0}' can't be unconditionally invoked because the receiver can be 'null'.",
+    "The method '{0}' can't be unconditionally invoked because the receiver "
+        "can be 'null'.",
     correctionMessage:
-        "Try making the call conditional (using '?.') or adding a null check to the target ('!').",
+        "Try making the call conditional (using '?.') or adding a null check "
+        "to the target ('!').",
     hasPublishedDocs: true,
     uniqueName: 'UNCHECKED_METHOD_INVOCATION_OF_NULLABLE_VALUE',
   );
@@ -13543,7 +13783,8 @@
   static const CompileTimeErrorCode
       UNCHECKED_OPERATOR_INVOCATION_OF_NULLABLE_VALUE = CompileTimeErrorCode(
     'UNCHECKED_USE_OF_NULLABLE_VALUE',
-    "The operator '{0}' can't be unconditionally invoked because the receiver can be 'null'.",
+    "The operator '{0}' can't be unconditionally invoked because the receiver "
+        "can be 'null'.",
     correctionMessage: "Try adding a null check to the target ('!').",
     hasPublishedDocs: true,
     uniqueName: 'UNCHECKED_OPERATOR_INVOCATION_OF_NULLABLE_VALUE',
@@ -13552,9 +13793,11 @@
   static const CompileTimeErrorCode
       UNCHECKED_PROPERTY_ACCESS_OF_NULLABLE_VALUE = CompileTimeErrorCode(
     'UNCHECKED_USE_OF_NULLABLE_VALUE',
-    "The property '{0}' can't be unconditionally accessed because the receiver can be 'null'.",
+    "The property '{0}' can't be unconditionally accessed because the receiver "
+        "can be 'null'.",
     correctionMessage:
-        "Try making the access conditional (using '?.') or adding a null check to the target ('!').",
+        "Try making the access conditional (using '?.') or adding a null check "
+        "to the target ('!').",
     hasPublishedDocs: true,
     uniqueName: 'UNCHECKED_PROPERTY_ACCESS_OF_NULLABLE_VALUE',
   );
@@ -13619,7 +13862,8 @@
     'UNCHECKED_USE_OF_NULLABLE_VALUE',
     "A nullable expression can't be used as a condition.",
     correctionMessage:
-        "Try checking that the value isn't 'null' before using it as a condition.",
+        "Try checking that the value isn't 'null' before using it as a "
+        "condition.",
     hasPublishedDocs: true,
     uniqueName: 'UNCHECKED_USE_OF_NULLABLE_VALUE_AS_CONDITION',
   );
@@ -13629,7 +13873,8 @@
     'UNCHECKED_USE_OF_NULLABLE_VALUE',
     "A nullable expression can't be used as an iterator in a for-in loop.",
     correctionMessage:
-        "Try checking that the value isn't 'null' before using it as an iterator.",
+        "Try checking that the value isn't 'null' before using it as an "
+        "iterator.",
     hasPublishedDocs: true,
     uniqueName: 'UNCHECKED_USE_OF_NULLABLE_VALUE_AS_ITERATOR',
   );
@@ -13639,7 +13884,8 @@
     'UNCHECKED_USE_OF_NULLABLE_VALUE',
     "A nullable expression can't be used in a spread.",
     correctionMessage:
-        "Try checking that the value isn't 'null' before using it in a spread, or use a null-aware spread.",
+        "Try checking that the value isn't 'null' before using it in a spread, "
+        "or use a null-aware spread.",
     hasPublishedDocs: true,
     uniqueName: 'UNCHECKED_USE_OF_NULLABLE_VALUE_IN_SPREAD',
   );
@@ -13649,7 +13895,8 @@
     'UNCHECKED_USE_OF_NULLABLE_VALUE',
     "A nullable expression can't be used in a yield-each statement.",
     correctionMessage:
-        "Try checking that the value isn't 'null' before using it in a yield-each statement.",
+        "Try checking that the value isn't 'null' before using it in a "
+        "yield-each statement.",
     hasPublishedDocs: true,
     uniqueName: 'UNCHECKED_USE_OF_NULLABLE_VALUE_IN_YIELD_EACH',
   );
@@ -13739,7 +13986,8 @@
     'UNDEFINED_CLASS',
     "Undefined class '{0}'.",
     correctionMessage:
-        "Try changing the name to the name of an existing class, or creating a class with the name '{0}'.",
+        "Try changing the name to the name of an existing class, or creating a "
+        "class with the name '{0}'.",
     hasPublishedDocs: true,
     isUnresolvedIdentifier: true,
   );
@@ -13829,7 +14077,8 @@
     'UNDEFINED_CONSTRUCTOR_IN_INITIALIZER',
     "The class '{0}' doesn't have a constructor named '{1}'.",
     correctionMessage:
-        "Try defining a constructor named '{1}' in '{0}', or invoking a different constructor.",
+        "Try defining a constructor named '{1}' in '{0}', or invoking a "
+        "different constructor.",
     hasPublishedDocs: true,
   );
 
@@ -13842,7 +14091,8 @@
     'UNDEFINED_CONSTRUCTOR_IN_INITIALIZER',
     "The class '{0}' doesn't have an unnamed constructor.",
     correctionMessage:
-        "Try defining an unnamed constructor in '{0}', or invoking a different constructor.",
+        "Try defining an unnamed constructor in '{0}', or invoking a different "
+        "constructor.",
     hasPublishedDocs: true,
     uniqueName: 'UNDEFINED_CONSTRUCTOR_IN_INITIALIZER_DEFAULT',
   );
@@ -13893,7 +14143,8 @@
     'UNDEFINED_ENUM_CONSTANT',
     "There's no constant named '{0}' in '{1}'.",
     correctionMessage:
-        "Try correcting the name to the name of an existing constant, or defining a constant named '{0}'.",
+        "Try correcting the name to the name of an existing constant, or "
+        "defining a constant named '{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -13995,7 +14246,8 @@
     'UNDEFINED_EXTENSION_GETTER',
     "The getter '{0}' isn't defined for the extension '{1}'.",
     correctionMessage:
-        "Try correcting the name to the name of an existing getter, or defining a getter named '{0}'.",
+        "Try correcting the name to the name of an existing getter, or "
+        "defining a getter named '{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -14097,7 +14349,8 @@
     'UNDEFINED_EXTENSION_METHOD',
     "The method '{0}' isn't defined for the extension '{1}'.",
     correctionMessage:
-        "Try correcting the name to the name of an existing method, or defining a method named '{0}'.",
+        "Try correcting the name to the name of an existing method, or "
+        "defining a method named '{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -14254,7 +14507,8 @@
     'UNDEFINED_EXTENSION_SETTER',
     "The setter '{0}' isn't defined for the extension '{1}'.",
     correctionMessage:
-        "Try correcting the name to the name of an existing setter, or defining a setter named '{0}'.",
+        "Try correcting the name to the name of an existing setter, or "
+        "defining a setter named '{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -14301,7 +14555,8 @@
     'UNDEFINED_FUNCTION',
     "The function '{0}' isn't defined.",
     correctionMessage:
-        "Try importing the library that defines '{0}', correcting the name to the name of an existing function, or defining a function named '{0}'.",
+        "Try importing the library that defines '{0}', correcting the name to "
+        "the name of an existing function, or defining a function named '{0}'.",
     hasPublishedDocs: true,
     isUnresolvedIdentifier: true,
   );
@@ -14339,7 +14594,9 @@
     'UNDEFINED_GETTER',
     "The getter '{0}' isn't defined for the type '{1}'.",
     correctionMessage:
-        "Try importing the library that defines '{0}', correcting the name to the name of an existing getter, or defining a getter or field named '{0}'.",
+        "Try importing the library that defines '{0}', correcting the name to "
+        "the name of an existing getter, or defining a getter or field named "
+        "'{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -14353,7 +14610,8 @@
     'UNDEFINED_GETTER',
     "The getter '{0}' isn't defined for the '{1}' function type.",
     correctionMessage:
-        "Try wrapping the function type alias in parentheses in order to access '{0}' as an extension getter on 'Type'.",
+        "Try wrapping the function type alias in parentheses in order to "
+        "access '{0}' as an extension getter on 'Type'.",
     hasPublishedDocs: true,
     uniqueName: 'UNDEFINED_GETTER_ON_FUNCTION_TYPE',
   );
@@ -14430,7 +14688,8 @@
     'UNDEFINED_IDENTIFIER_AWAIT',
     "Undefined name 'await' in function body not marked with 'async'.",
     correctionMessage:
-        "Try correcting the name to one that is defined, defining the name, or adding 'async' to the enclosing function body.",
+        "Try correcting the name to one that is defined, defining the name, or "
+        "adding 'async' to the enclosing function body.",
     hasPublishedDocs: true,
   );
 
@@ -14467,7 +14726,8 @@
     'UNDEFINED_METHOD',
     "The method '{0}' isn't defined for the type '{1}'.",
     correctionMessage:
-        "Try correcting the name to the name of an existing method, or defining a method named '{0}'.",
+        "Try correcting the name to the name of an existing method, or "
+        "defining a method named '{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -14481,7 +14741,8 @@
     'UNDEFINED_METHOD',
     "The method '{0}' isn't defined for the '{1}' function type.",
     correctionMessage:
-        "Try wrapping the function type alias in parentheses in order to access '{0}' as an extension method on 'Type'.",
+        "Try wrapping the function type alias in parentheses in order to "
+        "access '{0}' as an extension method on 'Type'.",
     hasPublishedDocs: true,
     uniqueName: 'UNDEFINED_METHOD_ON_FUNCTION_TYPE',
   );
@@ -14563,7 +14824,8 @@
     'UNDEFINED_NAMED_PARAMETER',
     "The named parameter '{0}' isn't defined.",
     correctionMessage:
-        "Try correcting the name to an existing named parameter's name, or defining a named parameter with the name '{0}'.",
+        "Try correcting the name to an existing named parameter's name, or "
+        "defining a named parameter with the name '{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -14638,9 +14900,11 @@
   static const CompileTimeErrorCode UNDEFINED_PREFIXED_NAME =
       CompileTimeErrorCode(
     'UNDEFINED_PREFIXED_NAME',
-    "The name '{0}' is being referenced through the prefix '{1}', but it isn't defined in any of the libraries imported using that prefix.",
+    "The name '{0}' is being referenced through the prefix '{1}', but it isn't "
+        "defined in any of the libraries imported using that prefix.",
     correctionMessage:
-        "Try correcting the prefix or importing the library that defines '{0}'.",
+        "Try correcting the prefix or importing the library that defines "
+        "'{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -14687,7 +14951,9 @@
     'UNDEFINED_SETTER',
     "The setter '{0}' isn't defined for the type '{1}'.",
     correctionMessage:
-        "Try importing the library that defines '{0}', correcting the name to the name of an existing setter, or defining a setter or field named '{0}'.",
+        "Try importing the library that defines '{0}', correcting the name to "
+        "the name of an existing setter, or defining a setter or field named "
+        "'{0}'.",
     hasPublishedDocs: true,
   );
 
@@ -14701,7 +14967,8 @@
     'UNDEFINED_SETTER',
     "The setter '{0}' isn't defined for the '{1}' function type.",
     correctionMessage:
-        "Try wrapping the function type alias in parentheses in order to access '{0}' as an extension getter on 'Type'.",
+        "Try wrapping the function type alias in parentheses in order to "
+        "access '{0}' as an extension getter on 'Type'.",
     hasPublishedDocs: true,
     uniqueName: 'UNDEFINED_SETTER_ON_FUNCTION_TYPE',
   );
@@ -14716,7 +14983,8 @@
     'UNDEFINED_SUPER_MEMBER',
     "The getter '{0}' isn't defined in a superclass of '{1}'.",
     correctionMessage:
-        "Try correcting the name to the name of an existing getter, or defining a getter or field named '{0}' in a superclass.",
+        "Try correcting the name to the name of an existing getter, or "
+        "defining a getter or field named '{0}' in a superclass.",
     hasPublishedDocs: true,
     uniqueName: 'UNDEFINED_SUPER_GETTER',
   );
@@ -14771,7 +15039,8 @@
     'UNDEFINED_SUPER_MEMBER',
     "The method '{0}' isn't defined in a superclass of '{1}'.",
     correctionMessage:
-        "Try correcting the name to the name of an existing method, or defining a method named '{0}' in a superclass.",
+        "Try correcting the name to the name of an existing method, or "
+        "defining a method named '{0}' in a superclass.",
     hasPublishedDocs: true,
     uniqueName: 'UNDEFINED_SUPER_METHOD',
   );
@@ -14800,7 +15069,8 @@
     'UNDEFINED_SUPER_MEMBER',
     "The setter '{0}' isn't defined in a superclass of '{1}'.",
     correctionMessage:
-        "Try correcting the name to the name of an existing setter, or defining a setter or field named '{0}' in a superclass.",
+        "Try correcting the name to the name of an existing setter, or "
+        "defining a setter or field named '{0}' in a superclass.",
     hasPublishedDocs: true,
     uniqueName: 'UNDEFINED_SUPER_SETTER',
   );
@@ -14852,7 +15122,8 @@
   static const CompileTimeErrorCode
       UNQUALIFIED_REFERENCE_TO_NON_LOCAL_STATIC_MEMBER = CompileTimeErrorCode(
     'UNQUALIFIED_REFERENCE_TO_NON_LOCAL_STATIC_MEMBER',
-    "Static members from supertypes must be qualified by the name of the defining type.",
+    "Static members from supertypes must be qualified by the name of the "
+        "defining type.",
     correctionMessage: "Try adding '{0}.' before the name.",
     hasPublishedDocs: true,
   );
@@ -14921,7 +15192,8 @@
       UNQUALIFIED_REFERENCE_TO_STATIC_MEMBER_OF_EXTENDED_TYPE =
       CompileTimeErrorCode(
     'UNQUALIFIED_REFERENCE_TO_STATIC_MEMBER_OF_EXTENDED_TYPE',
-    "Static members from the extended type or one of its superclasses must be qualified by the name of the defining type.",
+    "Static members from the extended type or one of its superclasses must be "
+        "qualified by the name of the defining type.",
     correctionMessage: "Try adding '{0}.' before the name.",
     hasPublishedDocs: true,
   );
@@ -14953,7 +15225,8 @@
     'URI_DOES_NOT_EXIST',
     "Target of URI doesn't exist: '{0}'.",
     correctionMessage:
-        "Try creating the file referenced by the URI, or Try using a URI for a file that does exist.",
+        "Try creating the file referenced by the URI, or Try using a URI for a "
+        "file that does exist.",
     hasPublishedDocs: true,
   );
 
@@ -14995,7 +15268,8 @@
     'URI_HAS_NOT_BEEN_GENERATED',
     "Target of URI hasn't been generated: '{0}'.",
     correctionMessage:
-        "Try running the generator that will generate the file referenced by the URI.",
+        "Try running the generator that will generate the file referenced by "
+        "the URI.",
     hasPublishedDocs: true,
   );
 
@@ -15097,7 +15371,9 @@
     'USE_OF_VOID_RESULT',
     "This expression has a type of 'void' so its value can't be used.",
     correctionMessage:
-        "Try checking to see if you're using the correct API; there might be a function or call that returns void you didn't expect. Also check type parameters and variables which might also be void.",
+        "Try checking to see if you're using the correct API; there might be a "
+        "function or call that returns void you didn't expect. Also check type "
+        "parameters and variables which might also be void.",
     hasPublishedDocs: true,
   );
 
@@ -15144,7 +15420,8 @@
   static const CompileTimeErrorCode VARIABLE_TYPE_MISMATCH =
       CompileTimeErrorCode(
     'VARIABLE_TYPE_MISMATCH',
-    "A value of type '{0}' can't be assigned to a const variable of type '{1}'.",
+    "A value of type '{0}' can't be assigned to a const variable of type "
+        "'{1}'.",
     correctionMessage: "Try using a subtype, or removing the 'const' keyword",
     hasPublishedDocs: true,
   );
@@ -15170,9 +15447,11 @@
       WRONG_EXPLICIT_TYPE_PARAMETER_VARIANCE_IN_SUPERINTERFACE =
       CompileTimeErrorCode(
     'WRONG_EXPLICIT_TYPE_PARAMETER_VARIANCE_IN_SUPERINTERFACE',
-    "'{0}' is an '{1}' type parameter and can't be used in an '{2}' position in '{3}'.",
+    "'{0}' is an '{1}' type parameter and can't be used in an '{2}' position "
+        "in '{3}'.",
     correctionMessage:
-        "Try using 'in' type parameters in 'in' positions and 'out' type parameters in 'out' positions in the superinterface.",
+        "Try using 'in' type parameters in 'in' positions and 'out' type "
+        "parameters in 'out' positions in the superinterface.",
   );
 
   /**
@@ -15329,9 +15608,11 @@
   static const CompileTimeErrorCode WRONG_NUMBER_OF_TYPE_ARGUMENTS =
       CompileTimeErrorCode(
     'WRONG_NUMBER_OF_TYPE_ARGUMENTS',
-    "The type '{0}' is declared with {1} type parameters, but {2} type arguments were given.",
+    "The type '{0}' is declared with {1} type parameters, but {2} type "
+        "arguments were given.",
     correctionMessage:
-        "Try adjusting the number of type arguments to match the number of type parameters.",
+        "Try adjusting the number of type arguments to match the number of "
+        "type parameters.",
     hasPublishedDocs: true,
   );
 
@@ -15343,9 +15624,11 @@
   static const CompileTimeErrorCode
       WRONG_NUMBER_OF_TYPE_ARGUMENTS_ANONYMOUS_FUNCTION = CompileTimeErrorCode(
     'WRONG_NUMBER_OF_TYPE_ARGUMENTS_FUNCTION',
-    "This function is declared with {0} type parameters, but {1} type arguments were given.",
+    "This function is declared with {0} type parameters, but {1} type "
+        "arguments were given.",
     correctionMessage:
-        "Try adjusting the number of type arguments to match the number of type parameters.",
+        "Try adjusting the number of type arguments to match the number of "
+        "type parameters.",
     uniqueName: 'WRONG_NUMBER_OF_TYPE_ARGUMENTS_ANONYMOUS_FUNCTION',
   );
 
@@ -15449,7 +15732,8 @@
   static const CompileTimeErrorCode WRONG_NUMBER_OF_TYPE_ARGUMENTS_EXTENSION =
       CompileTimeErrorCode(
     'WRONG_NUMBER_OF_TYPE_ARGUMENTS_EXTENSION',
-    "The extension '{0}' is declared with {1} type parameters, but {2} type arguments were given.",
+    "The extension '{0}' is declared with {1} type parameters, but {2} type "
+        "arguments were given.",
     correctionMessage: "Try adjusting the number of type arguments.",
     hasPublishedDocs: true,
   );
@@ -15463,9 +15747,11 @@
   static const CompileTimeErrorCode WRONG_NUMBER_OF_TYPE_ARGUMENTS_FUNCTION =
       CompileTimeErrorCode(
     'WRONG_NUMBER_OF_TYPE_ARGUMENTS_FUNCTION',
-    "The function '{0}' is declared with {1} type parameters, but {2} type arguments were given.",
+    "The function '{0}' is declared with {1} type parameters, but {2} type "
+        "arguments were given.",
     correctionMessage:
-        "Try adjusting the number of type arguments to match the number of type parameters.",
+        "Try adjusting the number of type arguments to match the number of "
+        "type parameters.",
   );
 
   /**
@@ -15520,7 +15806,8 @@
   static const CompileTimeErrorCode WRONG_NUMBER_OF_TYPE_ARGUMENTS_METHOD =
       CompileTimeErrorCode(
     'WRONG_NUMBER_OF_TYPE_ARGUMENTS_METHOD',
-    "The method '{0}' is declared with {1} type parameters, but {2} type arguments are given.",
+    "The method '{0}' is declared with {1} type parameters, but {2} type "
+        "arguments are given.",
     correctionMessage: "Try adjusting the number of type arguments.",
     hasPublishedDocs: true,
   );
@@ -15535,7 +15822,9 @@
     'WRONG_TYPE_PARAMETER_VARIANCE_IN_SUPERINTERFACE',
     "'{0}' can't be used contravariantly or invariantly in '{1}'.",
     correctionMessage:
-        "Try not using class type parameters in types of formal parameters of function types, nor in explicitly contravariant or invariant superinterfaces.",
+        "Try not using class type parameters in types of formal parameters of "
+        "function types, nor in explicitly contravariant or invariant "
+        "superinterfaces.",
   );
 
   /**
@@ -15561,7 +15850,9 @@
     'WRONG_TYPE_PARAMETER_VARIANCE_POSITION',
     "The '{0}' type parameter '{1}' can't be used in an '{2}' position.",
     correctionMessage:
-        "Try removing the type parameter or change the explicit variance modifier declaration for the type parameter to another one of 'in', 'out', or 'inout'.",
+        "Try removing the type parameter or change the explicit variance "
+        "modifier declaration for the type parameter to another one of 'in', "
+        "'out', or 'inout'.",
   );
 
   /**
@@ -15607,7 +15898,8 @@
   static const CompileTimeErrorCode YIELD_EACH_IN_NON_GENERATOR =
       CompileTimeErrorCode(
     'YIELD_IN_NON_GENERATOR',
-    "Yield-each statements must be in a generator function (one marked with either 'async*' or 'sync*').",
+    "Yield-each statements must be in a generator function (one marked with "
+        "either 'async*' or 'sync*').",
     correctionMessage:
         "Try adding 'async*' or 'sync*' to the enclosing function.",
     hasPublishedDocs: true,
@@ -15622,7 +15914,8 @@
   static const CompileTimeErrorCode YIELD_EACH_OF_INVALID_TYPE =
       CompileTimeErrorCode(
     'YIELD_OF_INVALID_TYPE',
-    "The type '{0}' implied by the 'yield*' expression must be assignable to '{1}'.",
+    "The type '{0}' implied by the 'yield*' expression must be assignable to "
+        "'{1}'.",
     hasPublishedDocs: true,
     uniqueName: 'YIELD_EACH_OF_INVALID_TYPE',
   );
@@ -15636,7 +15929,8 @@
   static const CompileTimeErrorCode YIELD_IN_NON_GENERATOR =
       CompileTimeErrorCode(
     'YIELD_IN_NON_GENERATOR',
-    "Yield statements must be in a generator function (one marked with either 'async*' or 'sync*').",
+    "Yield statements must be in a generator function (one marked with either "
+        "'async*' or 'sync*').",
     correctionMessage:
         "Try adding 'async*' or 'sync*' to the enclosing function.",
     hasPublishedDocs: true,
@@ -15722,70 +16016,80 @@
     'IMPLICIT_DYNAMIC_FIELD',
     "Missing field type for '{0}'.",
     correctionMessage:
-        "Try adding an explicit type, or remove implicit-dynamic from your analysis options file.",
+        "Try adding an explicit type, or remove implicit-dynamic from your "
+        "analysis options file.",
   );
 
   static const LanguageCode IMPLICIT_DYNAMIC_FUNCTION = LanguageCode(
     'IMPLICIT_DYNAMIC_FUNCTION',
     "Missing type arguments for generic function '{0}<{1}>'.",
     correctionMessage:
-        "Try adding an explicit type, or remove implicit-dynamic from your analysis options file.",
+        "Try adding an explicit type, or remove implicit-dynamic from your "
+        "analysis options file.",
   );
 
   static const LanguageCode IMPLICIT_DYNAMIC_INVOKE = LanguageCode(
     'IMPLICIT_DYNAMIC_INVOKE',
     "Missing type arguments for calling generic function type '{0}'.",
     correctionMessage:
-        "Try adding an explicit type, or remove implicit-dynamic from your analysis options file.",
+        "Try adding an explicit type, or remove implicit-dynamic from your "
+        "analysis options file.",
   );
 
   static const LanguageCode IMPLICIT_DYNAMIC_LIST_LITERAL = LanguageCode(
     'IMPLICIT_DYNAMIC_LIST_LITERAL',
     "Missing type argument for list literal.",
     correctionMessage:
-        "Try adding an explicit type, or remove implicit-dynamic from your analysis options file.",
+        "Try adding an explicit type, or remove implicit-dynamic from your "
+        "analysis options file.",
   );
 
   static const LanguageCode IMPLICIT_DYNAMIC_MAP_LITERAL = LanguageCode(
     'IMPLICIT_DYNAMIC_MAP_LITERAL',
     "Missing type arguments for map literal.",
     correctionMessage:
-        "Try adding an explicit type, or remove implicit-dynamic from your analysis options file.",
+        "Try adding an explicit type, or remove implicit-dynamic from your "
+        "analysis options file.",
   );
 
   static const LanguageCode IMPLICIT_DYNAMIC_METHOD = LanguageCode(
     'IMPLICIT_DYNAMIC_METHOD',
     "Missing type arguments for generic method '{0}<{1}>'.",
     correctionMessage:
-        "Try adding an explicit type, or remove implicit-dynamic from your analysis options file.",
+        "Try adding an explicit type, or remove implicit-dynamic from your "
+        "analysis options file.",
   );
 
   static const LanguageCode IMPLICIT_DYNAMIC_PARAMETER = LanguageCode(
     'IMPLICIT_DYNAMIC_PARAMETER',
     "Missing parameter type for '{0}'.",
     correctionMessage:
-        "Try adding an explicit type, or remove implicit-dynamic from your analysis options file.",
+        "Try adding an explicit type, or remove implicit-dynamic from your "
+        "analysis options file.",
   );
 
   static const LanguageCode IMPLICIT_DYNAMIC_RETURN = LanguageCode(
     'IMPLICIT_DYNAMIC_RETURN',
     "Missing return type for '{0}'.",
     correctionMessage:
-        "Try adding an explicit type, or remove implicit-dynamic from your analysis options file.",
+        "Try adding an explicit type, or remove implicit-dynamic from your "
+        "analysis options file.",
   );
 
   static const LanguageCode IMPLICIT_DYNAMIC_TYPE = LanguageCode(
     'IMPLICIT_DYNAMIC_TYPE',
     "Missing type arguments for generic type '{0}'.",
     correctionMessage:
-        "Try adding an explicit type, or remove implicit-dynamic from your analysis options file.",
+        "Try adding an explicit type, or remove implicit-dynamic from your "
+        "analysis options file.",
   );
 
   static const LanguageCode IMPLICIT_DYNAMIC_VARIABLE = LanguageCode(
     'IMPLICIT_DYNAMIC_VARIABLE',
     "Missing variable type for '{0}'.",
     correctionMessage:
-        "Try adding an explicit type, or remove implicit-dynamic from your analysis options file.",
+        "Try adding an explicit type, or remove implicit-dynamic from your "
+        "analysis options file.",
   );
 
   /// Initialize a newly created error code to have the given [name].
@@ -15972,7 +16276,8 @@
   static const StaticWarningCode INVALID_NULL_AWARE_OPERATOR =
       StaticWarningCode(
     'INVALID_NULL_AWARE_OPERATOR',
-    "The receiver can't be null, so the null-aware operator '{0}' is unnecessary.",
+    "The receiver can't be null, so the null-aware operator '{0}' is "
+        "unnecessary.",
     correctionMessage: "Try replacing the operator '{0}' with '{1}'.",
     hasPublishedDocs: true,
   );
@@ -15985,7 +16290,8 @@
   static const StaticWarningCode
       INVALID_NULL_AWARE_OPERATOR_AFTER_SHORT_CIRCUIT = StaticWarningCode(
     'INVALID_NULL_AWARE_OPERATOR',
-    "The receiver can't be null because of short-circuiting, so the null-aware operator '{0}' can't be used.",
+    "The receiver can't be null because of short-circuiting, so the null-aware "
+        "operator '{0}' can't be used.",
     correctionMessage: "Try replacing the operator '{0}' with '{1}'.",
     hasPublishedDocs: true,
     uniqueName: 'INVALID_NULL_AWARE_OPERATOR_AFTER_SHORT_CIRCUIT',
@@ -16001,7 +16307,8 @@
   static const StaticWarningCode
       INVALID_OVERRIDE_DIFFERENT_DEFAULT_VALUES_NAMED = StaticWarningCode(
     'INVALID_OVERRIDE_DIFFERENT_DEFAULT_VALUES_NAMED',
-    "Parameters can't override default values, this method overrides '{0}.{1}' where '{2}' has a different value.",
+    "Parameters can't override default values, this method overrides '{0}.{1}' "
+        "where '{2}' has a different value.",
     correctionMessage: "Try using the same default value in both methods.",
   );
 
@@ -16015,7 +16322,8 @@
   static const StaticWarningCode
       INVALID_OVERRIDE_DIFFERENT_DEFAULT_VALUES_POSITIONAL = StaticWarningCode(
     'INVALID_OVERRIDE_DIFFERENT_DEFAULT_VALUES_POSITIONAL',
-    "Parameters can't override default values, this method overrides '{0}.{1}' where this positional parameter has a different value.",
+    "Parameters can't override default values, this method overrides '{0}.{1}' "
+        "where this positional parameter has a different value.",
     correctionMessage: "Try using the same default value in both methods.",
   );
 
@@ -16087,7 +16395,8 @@
     'MISSING_ENUM_CONSTANT_IN_SWITCH',
     "Missing case clause for '{0}'.",
     correctionMessage:
-        "Try adding a case clause for the missing constant, or adding a default clause.",
+        "Try adding a case clause for the missing constant, or adding a "
+        "default clause.",
     hasPublishedDocs: true,
   );
 
diff --git a/pkg/analyzer/lib/src/error/unused_local_elements_verifier.dart b/pkg/analyzer/lib/src/error/unused_local_elements_verifier.dart
index 0d64b24..9984e82 100644
--- a/pkg/analyzer/lib/src/error/unused_local_elements_verifier.dart
+++ b/pkg/analyzer/lib/src/error/unused_local_elements_verifier.dart
@@ -439,15 +439,12 @@
     if (element.isSynthetic) {
       return true;
     }
-    if (_hasPragmaVmEntryPoint(element)) {
-      return true;
-    }
     if (element is LocalVariableElement ||
         element is FunctionElement && !element.isStatic) {
       // local variable or function
     } else if (element is ParameterElement) {
       var enclosingElement = element.enclosingElement;
-      // Only report unused parameters of methods or functions.
+      // Only report unused parameters of constructors, methods, and functions.
       if (enclosingElement is! ConstructorElement &&
           enclosingElement is! FunctionElement &&
           enclosingElement is! MethodElement) {
@@ -457,7 +454,22 @@
       if (!element.isOptional) {
         return true;
       }
+      if (enclosingElement is ConstructorElement &&
+          enclosingElement.enclosingElement.typeParameters.isNotEmpty) {
+        // There is an issue matching arguments of instance creation
+        // expressions for generic classes with parameters, so for now,
+        // consider every parameter of a constructor of a generic class
+        // "used". See https://github.com/dart-lang/sdk/issues/47839.
+        return true;
+      }
       if (enclosingElement is ExecutableElement) {
+        if (enclosingElement.typeParameters.isNotEmpty) {
+          // There is an issue matching arguments of generic function
+          // invocations with parameters, so for now, consider every parameter
+          // of a generic function "used". See
+          // https://github.com/dart-lang/sdk/issues/47839.
+          return true;
+        }
         if (_isPubliclyAccessible(enclosingElement)) {
           return true;
         }
@@ -470,6 +482,9 @@
         return true;
       }
     }
+    if (_hasPragmaVmEntryPoint(element)) {
+      return true;
+    }
     return _usedElements.elements.contains(element);
   }
 
diff --git a/pkg/analyzer/lib/src/fasta/ast_builder.dart b/pkg/analyzer/lib/src/fasta/ast_builder.dart
index 6cfd05b..455a0f6 100644
--- a/pkg/analyzer/lib/src/fasta/ast_builder.dart
+++ b/pkg/analyzer/lib/src/fasta/ast_builder.dart
@@ -161,6 +161,9 @@
   /// `true` if enhanced enums are enabled
   final bool enableEnhancedEnums;
 
+  /// `true` if macros are enabled
+  final bool enableMacros;
+
   final FeatureSet _featureSet;
 
   AstBuilder(ErrorReporter? errorReporter, this.fileUri, this.isFullAst,
@@ -183,6 +186,7 @@
             _featureSet.isEnabled(Feature.named_arguments_anywhere),
         enableSuperParameters = _featureSet.isEnabled(Feature.super_parameters),
         enableEnhancedEnums = _featureSet.isEnabled(Feature.enhanced_enums),
+        enableMacros = _featureSet.isEnabled(Feature.macros),
         uri = uri ?? fileUri;
 
   NodeList<ClassMember> get currentDeclarationMembers {
@@ -240,11 +244,25 @@
   }
 
   @override
-  void beginClassDeclaration(Token begin, Token? abstractToken, Token name) {
+  void beginClassDeclaration(
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {
     assert(classDeclaration == null &&
         mixinDeclaration == null &&
         extensionDeclaration == null);
     push(_Modifiers()..abstractKeyword = abstractToken);
+    if (macroToken != null && !enableMacros) {
+      var feature = ExperimentalFeatures.macros;
+      handleRecoverableError(
+          templateExperimentNotEnabled.withArguments(
+            feature.enableString,
+            _versionAsString(ExperimentStatus.currentVersion),
+          ),
+          macroToken,
+          macroToken);
+      // Pretend that 'macro' didn't occur while this feature is incomplete.
+      macroToken = null;
+    }
+    push(macroToken ?? NullValue.Token);
   }
 
   @override
@@ -375,8 +393,21 @@
 
   @override
   void beginNamedMixinApplication(
-      Token begin, Token? abstractToken, Token name) {
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {
     push(_Modifiers()..abstractKeyword = abstractToken);
+    if (macroToken != null && !enableMacros) {
+      var feature = ExperimentalFeatures.macros;
+      handleRecoverableError(
+          templateExperimentNotEnabled.withArguments(
+            feature.enableString,
+            _versionAsString(ExperimentStatus.currentVersion),
+          ),
+          macroToken,
+          macroToken);
+      // Pretend that 'macro' didn't occur while this feature is incomplete.
+      macroToken = null;
+    }
+    push(macroToken ?? NullValue.Token);
   }
 
   @override
@@ -1474,14 +1505,18 @@
       // This is a temporary AST node that was constructed in
       // [endFunctionTypedFormalParameter]. We now deconstruct it and create
       // the final AST node.
-      if (thisKeyword == null && superKeyword == null) {
-        node = ast.functionTypedFormalParameter2(
+      if (superKeyword != null) {
+        assert(thisKeyword == null,
+            "Can't have both 'this' and 'super' in a parameter.");
+        node = ast.superFormalParameter(
             identifier: name!,
             comment: comment,
             metadata: metadata,
             covariantKeyword: covariantKeyword,
             requiredKeyword: requiredKeyword,
-            returnType: typeOrFunctionTypedParameter.returnType,
+            type: typeOrFunctionTypedParameter.returnType,
+            superKeyword: superKeyword,
+            period: periodAfterThisOrSuper!,
             typeParameters: typeOrFunctionTypedParameter.typeParameters,
             parameters: typeOrFunctionTypedParameter.parameters,
             question: typeOrFunctionTypedParameter.question);
@@ -1501,32 +1536,35 @@
             parameters: typeOrFunctionTypedParameter.parameters,
             question: typeOrFunctionTypedParameter.question);
       } else {
-        assert(superKeyword != null && thisKeyword == null);
-        node = ast.superFormalParameter(
+        node = ast.functionTypedFormalParameter2(
             identifier: name!,
             comment: comment,
             metadata: metadata,
             covariantKeyword: covariantKeyword,
             requiredKeyword: requiredKeyword,
-            type: typeOrFunctionTypedParameter.returnType,
-            superKeyword: superKeyword!,
-            period: periodAfterThisOrSuper!,
+            returnType: typeOrFunctionTypedParameter.returnType,
             typeParameters: typeOrFunctionTypedParameter.typeParameters,
             parameters: typeOrFunctionTypedParameter.parameters,
             question: typeOrFunctionTypedParameter.question);
       }
     } else {
       var type = typeOrFunctionTypedParameter as TypeAnnotation?;
-      if (thisKeyword == null) {
-        node = ast.simpleFormalParameter2(
+      if (superKeyword != null) {
+        assert(thisKeyword == null,
+            "Can't have both 'this' and 'super' in a parameter.");
+        node = ast.superFormalParameter(
             comment: comment,
             metadata: metadata,
             covariantKeyword: covariantKeyword,
             requiredKeyword: requiredKeyword,
             keyword: keyword,
             type: type,
-            identifier: name);
-      } else {
+            superKeyword: superKeyword,
+            period: periodAfterThisOrSuper!,
+            identifier: name!);
+      } else if (thisKeyword != null) {
+        assert(superKeyword == null,
+            "Can't have both 'this' and 'super' in a parameter.");
         node = ast.fieldFormalParameter2(
             comment: comment,
             metadata: metadata,
@@ -1537,6 +1575,15 @@
             thisKeyword: thisKeyword,
             period: thisKeyword.next!,
             identifier: name!);
+      } else {
+        node = ast.simpleFormalParameter2(
+            comment: comment,
+            metadata: metadata,
+            covariantKeyword: covariantKeyword,
+            requiredKeyword: requiredKeyword,
+            keyword: keyword,
+            type: type,
+            identifier: name);
       }
     }
 
@@ -2029,6 +2076,7 @@
     }
     var withClause = pop(NullValue.WithClause) as WithClause;
     var superclass = pop() as NamedType;
+    var macroKeyword = pop(NullValue.Token) as Token?;
     var modifiers = pop() as _Modifiers?;
     var typeParameters = pop() as TypeParameterList?;
     var name = pop() as SimpleIdentifier;
@@ -2043,6 +2091,7 @@
         typeParameters,
         equalsToken,
         abstractKeyword,
+        macroKeyword,
         superclass,
         withClause,
         implementsClause,
@@ -2627,6 +2676,7 @@
     var implementsClause = pop(NullValue.IdentifierList) as ImplementsClause?;
     var withClause = pop(NullValue.WithClause) as WithClause?;
     var extendsClause = pop(NullValue.ExtendsClause) as ExtendsClause?;
+    var macroKeyword = pop(NullValue.Token) as Token?;
     var modifiers = pop() as _Modifiers?;
     var typeParameters = pop() as TypeParameterList?;
     var name = pop() as SimpleIdentifier;
@@ -2639,6 +2689,7 @@
       comment,
       metadata,
       abstractKeyword,
+      macroKeyword,
       classKeyword,
       name,
       typeParameters,
@@ -2668,13 +2719,26 @@
 
   @override
   void handleCommentReference(
-      Token? newKeyword, Token? prefix, Token? period, Token token) {
-    Identifier identifier = ast.simpleIdentifier(token);
-    if (prefix != null) {
-      identifier = ast.prefixedIdentifier(ast.simpleIdentifier(prefix), period!,
-          identifier as SimpleIdentifier);
+    Token? newKeyword,
+    Token? firstToken,
+    Token? firstPeriod,
+    Token? secondToken,
+    Token? secondPeriod,
+    Token thirdToken,
+  ) {
+    var identifier = ast.simpleIdentifier(thirdToken);
+    if (firstToken != null) {
+      var target = ast.prefixedIdentifier(ast.simpleIdentifier(firstToken),
+          firstPeriod!, ast.simpleIdentifier(secondToken!));
+      var expression = ast.propertyAccess(target, secondPeriod!, identifier);
+      push(ast.commentReference(newKeyword, expression));
+    } else if (secondToken != null) {
+      var expression = ast.prefixedIdentifier(
+          ast.simpleIdentifier(secondToken), secondPeriod!, identifier);
+      push(ast.commentReference(newKeyword, expression));
+    } else {
+      push(ast.commentReference(newKeyword, identifier));
     }
-    push(ast.commentReference(newKeyword, identifier));
   }
 
   @override
@@ -2813,8 +2877,21 @@
       );
     }
 
-    declarations.add(enumDeclaration = ast.enumDeclaration(comment, metadata,
-        enumKeyword, name, leftBrace, [], [], leftBrace.endGroup!));
+    declarations.add(
+      enumDeclaration = ast.enumDeclaration2(
+        comment: comment,
+        metadata: metadata,
+        enumKeyword: enumKeyword,
+        name: name,
+        typeParameters: typeParameters,
+        withClause: withClause,
+        implementsClause: implementsClause,
+        leftBracket: leftBrace,
+        constants: [],
+        members: [],
+        rightBracket: leftBrace.endGroup!,
+      ),
+    );
   }
 
   @override
diff --git a/pkg/analyzer/lib/src/generated/constant.dart b/pkg/analyzer/lib/src/generated/constant.dart
index f17f0d2..4a09e59 100644
--- a/pkg/analyzer/lib/src/generated/constant.dart
+++ b/pkg/analyzer/lib/src/generated/constant.dart
@@ -99,9 +99,6 @@
   /// The library containing the expression(s) that will be evaluated.
   final LibraryElementImpl _library;
 
-  /// Initialize a newly created evaluator to evaluate expressions in the given
-  /// [source]. The [typeProvider] is the type provider used to access known
-  /// types.
   ConstantEvaluator(this._source, this._library);
 
   EvaluationResult evaluate(Expression expression) {
diff --git a/pkg/analyzer/lib/src/generated/element_resolver.dart b/pkg/analyzer/lib/src/generated/element_resolver.dart
index e64547d..c430007 100644
--- a/pkg/analyzer/lib/src/generated/element_resolver.dart
+++ b/pkg/analyzer/lib/src/generated/element_resolver.dart
@@ -10,9 +10,9 @@
 import 'package:analyzer/src/dart/ast/ast.dart';
 import 'package:analyzer/src/dart/element/element.dart';
 import 'package:analyzer/src/dart/element/type_provider.dart';
+import 'package:analyzer/src/dart/resolver/comment_reference_resolver.dart';
 import 'package:analyzer/src/dart/resolver/method_invocation_resolver.dart';
 import 'package:analyzer/src/dart/resolver/scope.dart';
-import 'package:analyzer/src/dart/resolver/type_property_resolver.dart';
 import 'package:analyzer/src/error/codes.dart';
 import 'package:analyzer/src/generated/migratable_ast_info_provider.dart';
 import 'package:analyzer/src/generated/resolver.dart';
@@ -81,18 +81,17 @@
   /// The element for the library containing the compilation unit being visited.
   final LibraryElement _definingLibrary;
 
-  /// Helper for resolving properties on types.
-  final TypePropertyResolver _typePropertyResolver;
-
   final MethodInvocationResolver _methodInvocationResolver;
 
+  late final _commentReferenceResolver =
+      CommentReferenceResolver(_typeProvider, _resolver);
+
   /// Initialize a newly created visitor to work for the given [_resolver] to
   /// resolve the nodes in a compilation unit.
   ElementResolver(this._resolver,
       {MigratableAstInfoProvider migratableAstInfoProvider =
           const MigratableAstInfoProvider()})
       : _definingLibrary = _resolver.definingLibrary,
-        _typePropertyResolver = _resolver.typePropertyResolver,
         _methodInvocationResolver = MethodInvocationResolver(
           _resolver,
           migratableAstInfoProvider,
@@ -124,70 +123,8 @@
   }
 
   @override
-  void visitCommentReference(covariant CommentReferenceImpl node) {
-    var expression = node.expression;
-    if (expression is SimpleIdentifierImpl) {
-      var element = _resolveSimpleIdentifier(expression);
-      if (element == null) {
-        return;
-      }
-      expression.staticElement = element;
-      if (node.newKeyword != null) {
-        if (element is ClassElement) {
-          var constructor = element.unnamedConstructor;
-          if (constructor == null) {
-            // TODO(brianwilkerson) Report this error.
-          } else {
-            expression.staticElement = constructor;
-          }
-        } else {
-          // TODO(brianwilkerson) Report this error.
-        }
-      }
-    } else if (expression is PrefixedIdentifierImpl) {
-      var prefix = expression.prefix;
-      var prefixElement = _resolveSimpleIdentifier(prefix);
-      prefix.staticElement = prefixElement;
-
-      var name = expression.identifier;
-
-      if (prefixElement == null) {
-        return;
-      }
-
-      if (prefixElement is PrefixElement) {
-        var prefixScope = prefixElement.scope;
-        var lookupResult = prefixScope.lookup(name.name);
-        var element = lookupResult.getter ?? lookupResult.setter;
-        element = _resolver.toLegacyElement(element);
-        name.staticElement = element;
-        return;
-      }
-
-      if (node.newKeyword == null) {
-        if (prefixElement is ClassElement) {
-          name.staticElement = prefixElement.getMethod(name.name) ??
-              prefixElement.getGetter(name.name) ??
-              prefixElement.getSetter(name.name) ??
-              prefixElement.getNamedConstructor(name.name);
-        } else if (prefixElement is ExtensionElement) {
-          name.staticElement = prefixElement.getMethod(name.name) ??
-              prefixElement.getGetter(name.name) ??
-              prefixElement.getSetter(name.name);
-        } else {
-          // TODO(brianwilkerson) Report this error.
-        }
-      } else if (prefixElement is ClassElement) {
-        var constructor = prefixElement.getNamedConstructor(name.name);
-        if (constructor == null) {
-          // TODO(brianwilkerson) Report this error.
-        } else {
-          name.staticElement = constructor;
-        }
-      } else {
-        // TODO(brianwilkerson) Report this error.
-      }
-    }
+  void visitCommentReference(CommentReference node) {
+    _commentReferenceResolver.resolve(node);
   }
 
   @override
@@ -571,88 +508,6 @@
     _resolveAnnotations(node.metadata);
   }
 
-  /// Resolve the given simple [identifier] if possible. Return the element to
-  /// which it could be resolved, or `null` if it could not be resolved. This
-  /// does not record the results of the resolution.
-  Element? _resolveSimpleIdentifier(SimpleIdentifierImpl identifier) {
-    var lookupResult = identifier.scopeLookupResult!;
-
-    var element = lookupResult.getter;
-    element = _resolver.toLegacyElement(element);
-
-    if (element is PropertyAccessorElement && identifier.inSetterContext()) {
-      var setter = lookupResult.setter;
-      if (setter == null) {
-        //
-        // Check to see whether there might be a locally defined getter and
-        // an inherited setter.
-        //
-        var enclosingClass = _resolver.enclosingClass;
-        if (enclosingClass != null) {
-          var result = _typePropertyResolver.resolve(
-            receiver: null,
-            receiverType: enclosingClass.thisType,
-            name: identifier.name,
-            propertyErrorEntity: identifier,
-            nameErrorEntity: identifier,
-          );
-          setter = result.setter;
-        }
-      }
-      if (setter != null) {
-        setter = _resolver.toLegacyElement(setter);
-        element = setter;
-      }
-    } else if (element == null &&
-        (identifier.inSetterContext() ||
-            identifier.parent is CommentReference)) {
-      element = lookupResult.setter;
-      element = _resolver.toLegacyElement(element);
-    }
-    if (element == null) {
-      InterfaceType enclosingType;
-      var enclosingClass = _resolver.enclosingClass;
-      if (enclosingClass == null) {
-        var enclosingExtension = _resolver.enclosingExtension;
-        if (enclosingExtension == null) {
-          return null;
-        }
-        DartType extendedType =
-            _resolveTypeParameter(enclosingExtension.extendedType);
-        if (extendedType is InterfaceType) {
-          enclosingType = extendedType;
-        } else if (extendedType is FunctionType) {
-          enclosingType = _typeProvider.functionType;
-        } else {
-          return null;
-        }
-      } else {
-        enclosingType = enclosingClass.thisType;
-      }
-      if (element == null) {
-        var result = _typePropertyResolver.resolve(
-          receiver: null,
-          receiverType: enclosingType,
-          name: identifier.name,
-          propertyErrorEntity: identifier,
-          nameErrorEntity: identifier,
-        );
-        if (identifier.inSetterContext() ||
-            identifier.parent is CommentReference) {
-          element = result.setter;
-        }
-        element ??= result.getter;
-      }
-    }
-    return element;
-  }
-
-  /// If the given [type] is a type parameter, resolve it to the type that
-  /// should be used when looking up members. Otherwise, return the original
-  /// type.
-  DartType _resolveTypeParameter(DartType type) =>
-      type.resolveToBound(_typeProvider.objectType);
-
   /// Checks whether the given [expression] is a reference to a class. If it is
   /// then the element representing the class is returned, otherwise `null` is
   /// returned.
diff --git a/pkg/analyzer/lib/src/generated/engine.dart b/pkg/analyzer/lib/src/generated/engine.dart
index 86b03d0..6741d98 100644
--- a/pkg/analyzer/lib/src/generated/engine.dart
+++ b/pkg/analyzer/lib/src/generated/engine.dart
@@ -341,11 +341,6 @@
     nonPackageFeatureSet = featureSet;
   }
 
-  @deprecated
-  set enabledExperiments(List<String> enabledExperiments) {
-    _contextFeatures = ExperimentStatus.fromStrings(enabledExperiments);
-  }
-
   @override
   List<ErrorProcessor> get errorProcessors =>
       _errorProcessors ??= const <ErrorProcessor>[];
@@ -391,6 +386,7 @@
       buffer.addBool(implicitCasts);
       buffer.addBool(implicitDynamic);
       buffer.addBool(propagateLinterExceptions);
+      buffer.addBool(strictCasts);
       buffer.addBool(strictInference);
       buffer.addBool(strictRawTypes);
       buffer.addBool(useFastaParser);
diff --git a/pkg/analyzer/lib/src/generated/error_verifier.dart b/pkg/analyzer/lib/src/generated/error_verifier.dart
index 115365f..1d7d77c 100644
--- a/pkg/analyzer/lib/src/generated/error_verifier.dart
+++ b/pkg/analyzer/lib/src/generated/error_verifier.dart
@@ -42,9 +42,9 @@
 import 'package:analyzer/src/generated/element_resolver.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/error_detection_helpers.dart';
-import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/parser.dart' show ParserErrorCode;
 import 'package:analyzer/src/generated/this_access_tracker.dart';
+import 'package:analyzer/src/utilities/extensions/string.dart';
 import 'package:collection/collection.dart';
 
 class EnclosingExecutableContext {
@@ -86,16 +86,7 @@
   EnclosingExecutableContext.empty() : this(null);
 
   String? get displayName {
-    final element = this.element;
-    if (element is ConstructorElement) {
-      var className = element.enclosingElement.displayName;
-      var constructorName = element.displayName;
-      return constructorName.isEmpty
-          ? className
-          : '$className.$constructorName';
-    } else {
-      return element?.displayName;
-    }
+    return element?.displayName;
   }
 
   bool get isClosure {
@@ -1501,7 +1492,7 @@
           conflictingMembers.map((e) => _getLibraryName(e)).toList();
       libraryNames.sort();
       errorReporter.reportErrorForNode(CompileTimeErrorCode.AMBIGUOUS_IMPORT,
-          node, [name, StringUtilities.printListOfQuotedNames(libraryNames)]);
+          node, [name, libraryNames.quotedAndCommaSeparatedWithAnd]);
     }
   }
 
@@ -3188,6 +3179,10 @@
   /// See [CompileTimeErrorCode.MIXIN_INHERITS_FROM_NOT_OBJECT].
   bool _checkForMixinInheritsNotFromObject(
       NamedType mixinName, ClassElement mixinElement) {
+    if (mixinElement.isEnum) {
+      return false;
+    }
+
     var mixinSupertype = mixinElement.supertype;
     if (mixinSupertype == null || mixinSupertype.isDartCoreObject) {
       var mixins = mixinElement.mixins;
@@ -4164,6 +4159,15 @@
       return;
     }
 
+    // TODO(scheglov) Restore when working on errors.
+    if (_currentLibrary.featureSet.isEnabled(Feature.super_parameters)) {
+      if (constructor.parameters.parameters.any((parameter) {
+        return parameter.notDefault is SuperFormalParameter;
+      })) {
+        return;
+      }
+    }
+
     // Ignore if the constructor has either an implicit super constructor
     // invocation or a redirecting constructor invocation.
     for (ConstructorInitializer constructorInitializer
@@ -4930,11 +4934,11 @@
   /// Return the name of the library that defines given [element].
   String _getLibraryName(Element? element) {
     if (element == null) {
-      return StringUtilities.EMPTY;
+      return '';
     }
     var library = element.library;
     if (library == null) {
-      return StringUtilities.EMPTY;
+      return '';
     }
     List<ImportElement> imports = _currentLibrary.imports;
     int count = imports.length;
@@ -4963,7 +4967,7 @@
       buffer.write(" (via ");
       if (indirectCount > 1) {
         indirectSources.sort();
-        buffer.write(StringUtilities.printListOfQuotedNames(indirectSources));
+        buffer.write(indirectSources.quotedAndCommaSeparatedWithAnd);
       } else {
         buffer.write(indirectSources[0]);
       }
diff --git a/pkg/analyzer/lib/src/generated/ffi_verifier.dart b/pkg/analyzer/lib/src/generated/ffi_verifier.dart
index 69b37a5..53ec6ae 100644
--- a/pkg/analyzer/lib/src/generated/ffi_verifier.dart
+++ b/pkg/analyzer/lib/src/generated/ffi_verifier.dart
@@ -92,6 +92,7 @@
             _validatePackedAnnotation(node.metadata);
           }
         } else if (className == _abiSpecificIntegerClassName) {
+          _validateAbiSpecificIntegerAnnotation(node);
           _validateAbiSpecificIntegerMappingAnnotation(
               node.name, node.metadata);
         } else if (className != _allocatorClassName &&
@@ -102,7 +103,8 @@
               superclass.name,
               [node.name.name, superclass.name.name]);
         }
-      } else if (superclass.isCompoundSubtype) {
+      } else if (superclass.isCompoundSubtype ||
+          superclass.isAbiSpecificIntegerSubtype) {
         _errorReporter.reportErrorForNode(
             FfiCode.SUBTYPE_OF_STRUCT_CLASS_IN_EXTENDS,
             superclass,
@@ -120,7 +122,8 @@
       if (typename.ffiClass != null) {
         _errorReporter.reportErrorForNode(subtypeOfFfiCode, typename,
             [node.name.name, typename.name.toSource()]);
-      } else if (typename.isCompoundSubtype) {
+      } else if (typename.isCompoundSubtype ||
+          typename.isAbiSpecificIntegerSubtype) {
         _errorReporter.reportErrorForNode(subtypeOfStructCode, typename,
             [node.name.name, typename.name.toSource()]);
       }
@@ -614,6 +617,16 @@
     return _PrimitiveDartType.none;
   }
 
+  void _validateAbiSpecificIntegerAnnotation(ClassDeclaration node) {
+    if ((node.typeParameters?.length ?? 0) != 0 ||
+        node.members.length != 1 ||
+        node.members.single is! ConstructorDeclaration ||
+        (node.members.single as ConstructorDeclaration).constKeyword == null) {
+      _errorReporter.reportErrorForNode(
+          FfiCode.ABI_SPECIFIC_INTEGER_INVALID, node.name);
+    }
+  }
+
   /// Validate that the [annotations] include at most one mapping annotation.
   void _validateAbiSpecificIntegerMappingAnnotation(
       AstNode errorNode, NodeList<Annotation> annotations) {
@@ -1246,20 +1259,6 @@
 }
 
 extension on Annotation {
-  bool get isArray {
-    final element = this.element;
-    return element is ConstructorElement &&
-        element.ffiClass != null &&
-        element.enclosingElement.name == 'Array';
-  }
-
-  bool get isPacked {
-    final element = this.element;
-    return element is ConstructorElement &&
-        element.ffiClass != null &&
-        element.enclosingElement.name == 'Packed';
-  }
-
   bool get isAbiSpecificIntegerMapping {
     final element = this.element;
     return element is ConstructorElement &&
@@ -1267,16 +1266,12 @@
         element.enclosingElement.name ==
             FfiVerifier._abiSpecificIntegerMappingClassName;
   }
-}
 
-extension on ElementAnnotation {
   bool get isArray {
     final element = this.element;
     return element is ConstructorElement &&
         element.ffiClass != null &&
         element.enclosingElement.name == 'Array';
-    // Note: this is 'Array' instead of '_ArraySize' because it finds the
-    // forwarding factory instead of the forwarded constructor.
   }
 
   bool get isPacked {
@@ -1285,7 +1280,9 @@
         element.ffiClass != null &&
         element.enclosingElement.name == 'Packed';
   }
+}
 
+extension on ElementAnnotation {
   List<int> get arraySizeDimensions {
     assert(isArray);
     final value = computeConstantValue();
@@ -1321,6 +1318,22 @@
     return result;
   }
 
+  bool get isArray {
+    final element = this.element;
+    return element is ConstructorElement &&
+        element.ffiClass != null &&
+        element.enclosingElement.name == 'Array';
+    // Note: this is 'Array' instead of '_ArraySize' because it finds the
+    // forwarding factory instead of the forwarded constructor.
+  }
+
+  bool get isPacked {
+    final element = this.element;
+    return element is ConstructorElement &&
+        element.ffiClass != null &&
+        element.enclosingElement.name == 'Packed';
+  }
+
   int? get packedMemberAlignment {
     assert(isPacked);
     final value = computeConstantValue();
@@ -1329,6 +1342,33 @@
 }
 
 extension on Element? {
+  /// If this is a class element from `dart:ffi`, return it.
+  ClassElement? get ffiClass {
+    var element = this;
+    if (element is ConstructorElement) {
+      element = element.enclosingElement;
+    }
+    if (element is ClassElement && element.isFfiClass) {
+      return element;
+    }
+    return null;
+  }
+
+  /// Return `true` if this represents the class `AbiSpecificInteger`.
+  bool get isAbiSpecificInteger {
+    final element = this;
+    return element is ClassElement &&
+        element.name == FfiVerifier._abiSpecificIntegerClassName &&
+        element.isFfiClass;
+  }
+
+  /// Return `true` if this represents a subclass of the class
+  /// `AbiSpecificInteger`.
+  bool get isAbiSpecificIntegerSubclass {
+    final element = this;
+    return element is ClassElement && element.supertype.isAbiSpecificInteger;
+  }
+
   /// Return `true` if this represents the extension `AllocatorAlloc`.
   bool get isAllocatorExtension {
     final element = this;
@@ -1337,6 +1377,14 @@
         element.isFfiExtension;
   }
 
+  /// Return `true` if this represents the extension `DynamicLibraryExtension`.
+  bool get isDynamicLibraryExtension {
+    final element = this;
+    return element is ExtensionElement &&
+        element.name == 'DynamicLibraryExtension' &&
+        element.isFfiExtension;
+  }
+
   bool get isNativeFunctionPointerExtension {
     final element = this;
     return element is ExtensionElement &&
@@ -1358,14 +1406,6 @@
         element.isFfiExtension;
   }
 
-  /// Return `true` if this represents the extension `DynamicLibraryExtension`.
-  bool get isDynamicLibraryExtension {
-    final element = this;
-    return element is ExtensionElement &&
-        element.name == 'DynamicLibraryExtension' &&
-        element.isFfiExtension;
-  }
-
   /// Return `true` if this represents the class `Pointer`.
   bool get isPointer {
     final element = this;
@@ -1401,33 +1441,6 @@
     final element = this;
     return element is ClassElement && element.supertype.isUnion;
   }
-
-  /// Return `true` if this represents the class `AbiSpecificInteger`.
-  bool get isAbiSpecificInteger {
-    final element = this;
-    return element is ClassElement &&
-        element.name == FfiVerifier._abiSpecificIntegerClassName &&
-        element.isFfiClass;
-  }
-
-  /// Return `true` if this represents a subclass of the class
-  /// `AbiSpecificInteger`.
-  bool get isAbiSpecificIntegerSubclass {
-    final element = this;
-    return element is ClassElement && element.supertype.isAbiSpecificInteger;
-  }
-
-  /// If this is a class element from `dart:ffi`, return it.
-  ClassElement? get ffiClass {
-    var element = this;
-    if (element is ConstructorElement) {
-      element = element.enclosingElement;
-    }
-    if (element is ClassElement && element.isFfiClass) {
-      return element;
-    }
-    return null;
-  }
 }
 
 extension on ClassElement {
@@ -1474,6 +1487,11 @@
 }
 
 extension on DartType? {
+  bool get isAbiSpecificInteger {
+    final self = this;
+    return self is InterfaceType && self.element.isAbiSpecificInteger;
+  }
+
   bool get isStruct {
     final self = this;
     return self is InterfaceType && self.element.isStruct;
@@ -1483,24 +1501,9 @@
     final self = this;
     return self is InterfaceType && self.element.isUnion;
   }
-
-  bool get isAbiSpecificInteger {
-    final self = this;
-    return self is InterfaceType && self.element.isAbiSpecificInteger;
-  }
 }
 
 extension on DartType {
-  /// Return `true` if this represents the class `Array`.
-  bool get isArray {
-    final self = this;
-    if (self is InterfaceType) {
-      final element = self.element;
-      return element.name == FfiVerifier._arrayClassName && element.isFfiClass;
-    }
-    return false;
-  }
-
   int get arrayDimensions {
     DartType iterator = this;
     int dimensions = 0;
@@ -1523,9 +1526,65 @@
     return iterator;
   }
 
-  bool get isPointer {
+  bool get isAbiSpecificInteger {
     final self = this;
-    return self is InterfaceType && self.element.isPointer;
+    if (self is InterfaceType) {
+      final element = self.element;
+      final name = element.name;
+      return name == FfiVerifier._abiSpecificIntegerClassName &&
+          element.isFfiClass;
+    }
+    return false;
+  }
+
+  /// Returns `true` iff this is an Abi-specific integer type,
+  /// i.e. a subtype of `AbiSpecificInteger`.
+  bool get isAbiSpecificIntegerSubtype {
+    final self = this;
+    if (self is InterfaceType) {
+      final superType = self.element.supertype;
+      if (superType != null) {
+        final superClassElement = superType.element;
+        return superClassElement.name ==
+                FfiVerifier._abiSpecificIntegerClassName &&
+            superClassElement.isFfiClass;
+      }
+    }
+    return false;
+  }
+
+  /// Return `true` if this represents the class `Array`.
+  bool get isArray {
+    final self = this;
+    if (self is InterfaceType) {
+      final element = self.element;
+      return element.name == FfiVerifier._arrayClassName && element.isFfiClass;
+    }
+    return false;
+  }
+
+  bool get isCompound {
+    final self = this;
+    if (self is InterfaceType) {
+      final element = self.element;
+      final name = element.name;
+      return (name == FfiVerifier._structClassName ||
+              name == FfiVerifier._unionClassName) &&
+          element.isFfiClass;
+    }
+    return false;
+  }
+
+  /// Returns `true` if this is a struct type, i.e. a subtype of `Struct`.
+  bool get isCompoundSubtype {
+    final self = this;
+    if (self is InterfaceType) {
+      final superType = self.element.supertype;
+      if (superType != null) {
+        return superType.isCompound;
+      }
+    }
+    return false;
   }
 
   bool get isHandle {
@@ -1557,22 +1616,6 @@
     return false;
   }
 
-  /// Returns `true` iff this is an Abi-specific integer type,
-  /// i.e. a subtype of `AbiSpecificInteger`.
-  bool get isAbiSpecificIntegerSubtype {
-    final self = this;
-    if (self is InterfaceType) {
-      final superType = self.element.supertype;
-      if (superType != null) {
-        final superClassElement = superType.element;
-        return superClassElement.name ==
-                FfiVerifier._abiSpecificIntegerClassName &&
-            superClassElement.isFfiClass;
-      }
-    }
-    return false;
-  }
-
   /// Returns `true` iff this is a opaque type, i.e. a subtype of `Opaque`.
   bool get isOpaqueSubtype {
     final self = this;
@@ -1587,28 +1630,9 @@
     return false;
   }
 
-  bool get isCompound {
+  bool get isPointer {
     final self = this;
-    if (self is InterfaceType) {
-      final element = self.element;
-      final name = element.name;
-      return (name == FfiVerifier._structClassName ||
-              name == FfiVerifier._unionClassName) &&
-          element.isFfiClass;
-    }
-    return false;
-  }
-
-  /// Returns `true` if this is a struct type, i.e. a subtype of `Struct`.
-  bool get isCompoundSubtype {
-    final self = this;
-    if (self is InterfaceType) {
-      final superType = self.element.supertype;
-      if (superType != null) {
-        return superType.isCompound;
-      }
-    }
-    return false;
+    return self is InterfaceType && self.element.isPointer;
   }
 }
 
@@ -1619,6 +1643,15 @@
   }
 
   /// Return `true` if this represents a subtype of `Struct` or `Union`.
+  bool get isAbiSpecificIntegerSubtype {
+    var element = name.staticElement;
+    if (element is ClassElement) {
+      return element.allSupertypes.any((e) => e.isAbiSpecificInteger);
+    }
+    return false;
+  }
+
+  /// Return `true` if this represents a subtype of `Struct` or `Union`.
   bool get isCompoundSubtype {
     var element = name.staticElement;
     if (element is ClassElement) {
diff --git a/pkg/analyzer/lib/src/generated/java_engine.dart b/pkg/analyzer/lib/src/generated/java_engine.dart
deleted file mode 100644
index 82c2f23..0000000
--- a/pkg/analyzer/lib/src/generated/java_engine.dart
+++ /dev/null
@@ -1,264 +0,0 @@
-// Copyright (c) 2014, the Dart project authors. Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-import 'package:analyzer/src/generated/interner.dart';
-import 'package:analyzer/src/generated/java_core.dart';
-
-export 'package:analyzer/exception/exception.dart';
-
-/// A predicate is a one-argument function that returns a boolean value.
-typedef Predicate<E> = bool Function(E argument);
-
-class StringUtilities {
-  static const String EMPTY = '';
-  static const List<String> EMPTY_ARRAY = <String>[];
-
-  static Interner INTERNER = NullInterner();
-
-  /// Compute line starts for the given [content].
-  /// Lines end with `\r`, `\n` or `\r\n`.
-  static List<int> computeLineStarts(String content) {
-    List<int> lineStarts = <int>[0];
-    int length = content.length;
-    int unit;
-    for (int index = 0; index < length; index++) {
-      unit = content.codeUnitAt(index);
-      // Special-case \r\n.
-      if (unit == 0x0D /* \r */) {
-        // Peek ahead to detect a following \n.
-        if ((index + 1 < length) && content.codeUnitAt(index + 1) == 0x0A) {
-          // Line start will get registered at next index at the \n.
-        } else {
-          lineStarts.add(index + 1);
-        }
-      }
-      // \n
-      if (unit == 0x0A) {
-        lineStarts.add(index + 1);
-      }
-    }
-    return lineStarts;
-  }
-
-  static bool endsWith3(String str, int c1, int c2, int c3) {
-    var length = str.length;
-    return length >= 3 &&
-        str.codeUnitAt(length - 3) == c1 &&
-        str.codeUnitAt(length - 2) == c2 &&
-        str.codeUnitAt(length - 1) == c3;
-  }
-
-  static bool endsWithChar(String str, int c) {
-    int length = str.length;
-    return length > 0 && str.codeUnitAt(length - 1) == c;
-  }
-
-  static int indexOf1(String str, int start, int c) {
-    int index = start;
-    int last = str.length;
-    while (index < last) {
-      if (str.codeUnitAt(index) == c) {
-        return index;
-      }
-      index++;
-    }
-    return -1;
-  }
-
-  static int indexOf2(String str, int start, int c1, int c2) {
-    int index = start;
-    int last = str.length - 1;
-    while (index < last) {
-      if (str.codeUnitAt(index) == c1 && str.codeUnitAt(index + 1) == c2) {
-        return index;
-      }
-      index++;
-    }
-    return -1;
-  }
-
-  static int indexOf4(
-      String string, int start, int c1, int c2, int c3, int c4) {
-    int index = start;
-    int last = string.length - 3;
-    while (index < last) {
-      if (string.codeUnitAt(index) == c1 &&
-          string.codeUnitAt(index + 1) == c2 &&
-          string.codeUnitAt(index + 2) == c3 &&
-          string.codeUnitAt(index + 3) == c4) {
-        return index;
-      }
-      index++;
-    }
-    return -1;
-  }
-
-  static int indexOf5(
-      String str, int start, int c1, int c2, int c3, int c4, int c5) {
-    int index = start;
-    int last = str.length - 4;
-    while (index < last) {
-      if (str.codeUnitAt(index) == c1 &&
-          str.codeUnitAt(index + 1) == c2 &&
-          str.codeUnitAt(index + 2) == c3 &&
-          str.codeUnitAt(index + 3) == c4 &&
-          str.codeUnitAt(index + 4) == c5) {
-        return index;
-      }
-      index++;
-    }
-    return -1;
-  }
-
-  /// Return the index of the first not letter/digit character in the [string]
-  /// that is at or after the [startIndex]. Return the length of the [string] if
-  /// all characters to the end are letters/digits.
-  static int indexOfFirstNotLetterDigit(String string, int startIndex) {
-    int index = startIndex;
-    int last = string.length;
-    while (index < last) {
-      int c = string.codeUnitAt(index);
-      if (!Character.isLetterOrDigit(c)) {
-        return index;
-      }
-      index++;
-    }
-    return last;
-  }
-
-  static String intern(String string) => INTERNER.intern(string);
-  static bool isEmpty(String? s) {
-    return s == null || s.isEmpty;
-  }
-
-  static bool isTagName(String? s) {
-    if (s == null || s.isEmpty) {
-      return false;
-    }
-    int sz = s.length;
-    for (int i = 0; i < sz; i++) {
-      int c = s.codeUnitAt(i);
-      if (!Character.isLetter(c)) {
-        if (i == 0) {
-          return false;
-        }
-        if (!Character.isDigit(c) && c != 0x2D) {
-          return false;
-        }
-      }
-    }
-    return true;
-  }
-
-  /// Produce a string containing all of the names in the given array,
-  /// surrounded by single quotes, and separated by commas.
-  ///
-  /// The list must contain at least two elements.
-  ///
-  /// @param names the names to be printed
-  /// @return the result of printing the names
-  static String printListOfQuotedNames(List<String>? names) {
-    if (names == null) {
-      throw ArgumentError("The list must not be null");
-    }
-    int count = names.length;
-    if (count < 2) {
-      throw ArgumentError("The list must contain at least two names");
-    }
-    StringBuffer buffer = StringBuffer();
-    buffer.write("'");
-    buffer.write(names[0]);
-    buffer.write("'");
-    for (int i = 1; i < count - 1; i++) {
-      buffer.write(", '");
-      buffer.write(names[i]);
-      buffer.write("'");
-    }
-    buffer.write(" and '");
-    buffer.write(names[count - 1]);
-    buffer.write("'");
-    return buffer.toString();
-  }
-
-  static bool startsWith2(String str, int start, int c1, int c2) {
-    return str.length - start >= 2 &&
-        str.codeUnitAt(start) == c1 &&
-        str.codeUnitAt(start + 1) == c2;
-  }
-
-  static bool startsWith3(String str, int start, int c1, int c2, int c3) {
-    return str.length - start >= 3 &&
-        str.codeUnitAt(start) == c1 &&
-        str.codeUnitAt(start + 1) == c2 &&
-        str.codeUnitAt(start + 2) == c3;
-  }
-
-  static bool startsWith4(
-      String str, int start, int c1, int c2, int c3, int c4) {
-    return str.length - start >= 4 &&
-        str.codeUnitAt(start) == c1 &&
-        str.codeUnitAt(start + 1) == c2 &&
-        str.codeUnitAt(start + 2) == c3 &&
-        str.codeUnitAt(start + 3) == c4;
-  }
-
-  static bool startsWith5(
-      String str, int start, int c1, int c2, int c3, int c4, int c5) {
-    return str.length - start >= 5 &&
-        str.codeUnitAt(start) == c1 &&
-        str.codeUnitAt(start + 1) == c2 &&
-        str.codeUnitAt(start + 2) == c3 &&
-        str.codeUnitAt(start + 3) == c4 &&
-        str.codeUnitAt(start + 4) == c5;
-  }
-
-  static bool startsWith6(
-      String str, int start, int c1, int c2, int c3, int c4, int c5, int c6) {
-    return str.length - start >= 6 &&
-        str.codeUnitAt(start) == c1 &&
-        str.codeUnitAt(start + 1) == c2 &&
-        str.codeUnitAt(start + 2) == c3 &&
-        str.codeUnitAt(start + 3) == c4 &&
-        str.codeUnitAt(start + 4) == c5 &&
-        str.codeUnitAt(start + 5) == c6;
-  }
-
-  static String? substringBefore(String? str, String? separator) {
-    if (str == null || str.isEmpty) {
-      return str;
-    }
-    if (separator == null) {
-      return str;
-    }
-    int pos = str.indexOf(separator);
-    if (pos < 0) {
-      return str;
-    }
-    return str.substring(0, pos);
-  }
-
-  static String substringBeforeChar(String str, int c) {
-    if (isEmpty(str)) {
-      return str;
-    }
-    int pos = indexOf1(str, 0, c);
-    if (pos < 0) {
-      return str;
-    }
-    return str.substring(0, pos);
-  }
-}
-
-class UUID {
-  static const int __nextId = 0;
-
-  final String id;
-
-  UUID(this.id);
-
-  @override
-  String toString() => id;
-
-  static UUID randomUUID() => UUID((__nextId).toString());
-}
diff --git a/pkg/analyzer/lib/src/generated/resolver.dart b/pkg/analyzer/lib/src/generated/resolver.dart
index 80eebe3..ddcbc07 100644
--- a/pkg/analyzer/lib/src/generated/resolver.dart
+++ b/pkg/analyzer/lib/src/generated/resolver.dart
@@ -472,7 +472,6 @@
   }
 
   void checkForBodyMayCompleteNormally({
-    required DartType? returnType,
     required FunctionBody body,
     required AstNode errorNode,
   }) {
@@ -481,6 +480,12 @@
       return;
     }
 
+    // TODO(scheglov) encapsulate
+    var bodyContext = BodyInferenceContext.of(body);
+    if (bodyContext == null) {
+      return null;
+    }
+    var returnType = bodyContext.contextType;
     if (returnType == null) {
       return;
     }
@@ -490,24 +495,59 @@
         return;
       }
 
-      if (typeSystem.isPotentiallyNonNullable(returnType)) {
-        if (errorNode is ConstructorDeclaration) {
-          errorReporter.reportErrorForName(
-            CompileTimeErrorCode.BODY_MIGHT_COMPLETE_NORMALLY,
-            errorNode,
-          );
-        } else if (errorNode is BlockFunctionBody) {
-          errorReporter.reportErrorForToken(
-            CompileTimeErrorCode.BODY_MIGHT_COMPLETE_NORMALLY,
-            errorNode.block.leftBracket,
-          );
-        } else {
-          errorReporter.reportErrorForNode(
-            CompileTimeErrorCode.BODY_MIGHT_COMPLETE_NORMALLY,
-            errorNode,
-          );
+      if (body.isAsynchronous) {
+        // Check whether the return type is legal. If not, return rather than
+        // reporting a second error.
+
+        // This is the same check as [ReturnTypeVerifier._isLegalReturnType].
+        // TODO(srawlins): When this check is moved into the resolution stage,
+        // use the result of that check to determine whether this check should
+        // be done.
+        var lowerBound = typeProvider.futureElement.instantiate(
+          typeArguments: [NeverTypeImpl.instance],
+          nullabilitySuffix: NullabilitySuffix.star,
+        );
+        var imposedType = bodyContext.imposedType;
+        if (imposedType != null &&
+            !typeSystem.isSubtypeOf(lowerBound, imposedType)) {
+          // [imposedType] is an illegal return type for an asynchronous
+          // non-generator function; do not report an additional error here.
+          return;
         }
       }
+
+      ErrorCode errorCode;
+      if (typeSystem.isPotentiallyNonNullable(returnType)) {
+        errorCode = CompileTimeErrorCode.BODY_MIGHT_COMPLETE_NORMALLY;
+      } else {
+        var returnTypeBase = typeSystem.futureOrBase(returnType);
+        if (returnTypeBase.isVoid ||
+            returnTypeBase.isDynamic ||
+            returnTypeBase.isDartCoreNull) {
+          return;
+        } else {
+          errorCode = HintCode.BODY_MIGHT_COMPLETE_NORMALLY_NULLABLE;
+        }
+      }
+      if (errorNode is ConstructorDeclaration) {
+        errorReporter.reportErrorForName(
+          errorCode,
+          errorNode,
+          arguments: [returnType],
+        );
+      } else if (errorNode is BlockFunctionBody) {
+        errorReporter.reportErrorForToken(
+          errorCode,
+          errorNode.block.leftBracket,
+          [returnType],
+        );
+      } else {
+        errorReporter.reportErrorForNode(
+          errorCode,
+          errorNode,
+          [returnType],
+        );
+      }
     }
   }
 
@@ -1253,7 +1293,7 @@
   @override
   void visitCommentReference(CommentReference node) {
     //
-    // We do not visit the identifier because it needs to be visited in the
+    // We do not visit the expression because it needs to be visited in the
     // context of the reference.
     //
     node.accept(elementResolver);
@@ -1342,9 +1382,7 @@
     }
 
     if (node.factoryKeyword != null) {
-      var bodyContext = BodyInferenceContext.of(node.body);
       checkForBodyMayCompleteNormally(
-        returnType: bodyContext?.contextType,
         body: node.body,
         errorNode: node,
       );
@@ -1573,12 +1611,7 @@
     }
 
     if (!node.isSetter) {
-      // TODO(scheglov) encapsulate
-      var bodyContext = BodyInferenceContext.of(
-        node.functionExpression.body,
-      );
       checkForBodyMayCompleteNormally(
-        returnType: bodyContext?.contextType,
         body: node.functionExpression.body,
         errorNode: node.name,
       );
@@ -1804,10 +1837,7 @@
     }
 
     if (!node.isSetter) {
-      // TODO(scheglov) encapsulate
-      var bodyContext = BodyInferenceContext.of(node.body);
       checkForBodyMayCompleteNormally(
-        returnType: bodyContext?.contextType,
         body: node.body,
         errorNode: node.name,
       );
diff --git a/pkg/analyzer/lib/src/generated/testing/ast_test_factory.dart b/pkg/analyzer/lib/src/generated/testing/ast_test_factory.dart
index e05cbc0..9fb88ca 100644
--- a/pkg/analyzer/lib/src/generated/testing/ast_test_factory.dart
+++ b/pkg/analyzer/lib/src/generated/testing/ast_test_factory.dart
@@ -240,13 +240,15 @@
           ExtendsClause? extendsClause,
           WithClause? withClause,
           ImplementsClause? implementsClause,
-          [List<ClassMember> members = const []]) =>
+          {List<ClassMember> members = const [],
+          bool isMacro = false}) =>
       astFactory.classDeclaration(
           null,
           null,
           abstractKeyword == null
               ? null
               : TokenFactory.tokenFromKeyword(abstractKeyword),
+          isMacro ? TokenFactory.tokenFromString('macro') : null,
           TokenFactory.tokenFromKeyword(Keyword.CLASS),
           identifier3(name),
           typeParameters,
@@ -263,7 +265,8 @@
           Keyword? abstractKeyword,
           NamedType superclass,
           WithClause withClause,
-          ImplementsClause? implementsClause) =>
+          ImplementsClause? implementsClause,
+          {bool isMacro = false}) =>
       astFactory.classTypeAlias(
           null,
           null,
@@ -274,6 +277,7 @@
           abstractKeyword == null
               ? null
               : TokenFactory.tokenFromKeyword(abstractKeyword),
+          isMacro ? TokenFactory.tokenFromString('macro') : null,
           superclass,
           withClause,
           implementsClause,
@@ -458,30 +462,6 @@
   static EmptyStatementImpl emptyStatement() => astFactory
       .emptyStatement(TokenFactory.tokenFromType(TokenType.SEMICOLON));
 
-  static EnumDeclarationImpl enumDeclaration(
-          SimpleIdentifier name, List<EnumConstantDeclaration> constants) =>
-      astFactory.enumDeclaration(
-          null,
-          null,
-          TokenFactory.tokenFromKeyword(Keyword.ENUM),
-          name,
-          TokenFactory.tokenFromType(TokenType.OPEN_CURLY_BRACKET),
-          constants,
-          [],
-          TokenFactory.tokenFromType(TokenType.CLOSE_CURLY_BRACKET));
-
-  static EnumDeclarationImpl enumDeclaration2(
-      String name, List<String> constantNames) {
-    var constants = constantNames.map((name) {
-      return astFactory.enumConstantDeclaration(
-        null,
-        null,
-        identifier3(name),
-      );
-    }).toList();
-    return enumDeclaration(identifier3(name), constants);
-  }
-
   static ExportDirectiveImpl exportDirective(
           List<Annotation> metadata, String uri,
           [List<Combinator> combinators = const []]) =>
diff --git a/pkg/analyzer/lib/src/lint/analysis.dart b/pkg/analyzer/lib/src/lint/analysis.dart
index 2e6974e..7eb9520 100644
--- a/pkg/analyzer/lib/src/lint/analysis.dart
+++ b/pkg/analyzer/lib/src/lint/analysis.dart
@@ -67,10 +67,6 @@
   /// The path to a `.packages` configuration file
   String? packageConfigPath;
 
-  /// The path to the package root.
-  @Deprecated('https://github.com/dart-lang/sdk/issues/41197')
-  String? packageRootPath;
-
   /// Whether to use Dart's Strong Mode analyzer.
   bool strongMode = true;
 
diff --git a/pkg/analyzer/lib/src/lint/pub.dart b/pkg/analyzer/lib/src/lint/pub.dart
index 8c11a57..be9b149 100644
--- a/pkg/analyzer/lib/src/lint/pub.dart
+++ b/pkg/analyzer/lib/src/lint/pub.dart
@@ -37,6 +37,12 @@
 
 PSGitRepo? _processGitRepo(
     YamlScalar key, YamlNode v, ResourceProvider? resourceProvider) {
+  if (v is YamlScalar) {
+    _PSGitRepo repo = _PSGitRepo();
+    repo.token = _PSNode(key, resourceProvider);
+    repo.url = PSEntry(repo.token, _PSNode(v, resourceProvider));
+    return repo;
+  }
   if (v is! YamlMap) {
     return null;
   }
@@ -130,9 +136,44 @@
   String toString() => '${key != null ? (key.toString() + ': ') : ''}$value';
 }
 
+/// Representation of git-dependency in `pubspec.yaml`.
+///
+/// **Example** of a git-dependency:
+/// ```yaml
+/// dependencies:
+///   foo:
+///     git: # <-- this is the [token] property
+///       url: https://github.com/example/example
+///       ref: main # ref is optional
+/// ```
+///
+/// This may also be written in the form:
+/// ```yaml
+/// dependencies:
+///   foo:
+///     git:       https://github.com/example/example
+///     # ^-token  ^--url
+///     # In this case [ref] is `null`.
+/// ```
 abstract class PSGitRepo {
+  /// [PSEntry] for `ref: main` where [PSEntry.key] is `ref` and [PSEntry.value]
+  /// is `main`.
   PSEntry? get ref;
+
+  /// The `'git'` from the `pubspec.yaml`, this is the key that indicates this
+  /// is a git-dependency.
   PSNode? get token;
+
+  /// [PSEntry] for `url: https://...` or `git: https://`, where [PSEntry.key]
+  /// is either `url` or `git`, and [PSEntry.key] is the URL.
+  ///
+  /// If the git-dependency is given in the form:
+  /// ```yaml
+  /// dependencies:
+  ///   foo:
+  ///     git:       https://github.com/example/example
+  /// ```
+  /// Then [token] and [url.key] will be the same object.
   PSEntry? get url;
 }
 
diff --git a/pkg/analyzer/lib/src/lint/util.dart b/pkg/analyzer/lib/src/lint/util.dart
index a0c25dc..392df53 100644
--- a/pkg/analyzer/lib/src/lint/util.dart
+++ b/pkg/analyzer/lib/src/lint/util.dart
@@ -12,19 +12,8 @@
 import 'package:analyzer/src/dart/ast/token.dart';
 import 'package:path/path.dart' as path;
 
-final _identifier = RegExp(r'^([(_|$)a-zA-Z]+([_a-zA-Z0-9])*)$');
-
-final _lowerCamelCase = RegExp(r'^(_)*[?$a-z][a-z0-9?$]*([A-Z][a-z0-9?$]*)*$');
-
-final _lowerCaseUnderScore = RegExp(r'^([a-z]+([_]?[a-z0-9]+)*)+$');
-
-final _lowerCaseUnderScoreWithDots =
-    RegExp(r'^[a-z][_a-z0-9]*(\.[a-z][_a-z0-9]*)*$');
-
 final _pubspec = RegExp(r'^[_]?pubspec\.yaml$');
 
-final _underscores = RegExp(r'^[_]+$');
-
 /// Create a library name prefix based on [libraryPath], [projectRoot] and
 /// current [packageName].
 String createLibraryNamePrefix(
@@ -50,37 +39,9 @@
 /// Returns `true` if this [fileName] is a Dart file.
 bool isDartFileName(String fileName) => fileName.endsWith('.dart');
 
-/// Returns `true` if this [name] is a legal Dart identifier.
-@deprecated // Never intended for public use.
-bool isIdentifier(String name) => _identifier.hasMatch(name);
-
-/// Returns `true` of the given [name] is composed only of `_`s.
-@deprecated // Never intended for public use.
-bool isJustUnderscores(String name) => _underscores.hasMatch(name);
-
-/// Returns `true` if this [id] is `lowerCamelCase`.
-@deprecated // Never intended for public use.
-bool isLowerCamelCase(String id) =>
-    id.length == 1 && isUpperCase(id.codeUnitAt(0)) ||
-    id == '_' ||
-    _lowerCamelCase.hasMatch(id);
-
-/// Returns `true` if this [id] is `lower_camel_case_with_underscores`.
-@deprecated // Never intended for public use.
-bool isLowerCaseUnderScore(String id) => _lowerCaseUnderScore.hasMatch(id);
-
-/// Returns `true` if this [id] is `lower_camel_case_with_underscores_or.dots`.
-@deprecated // Never intended for public use.
-bool isLowerCaseUnderScoreWithDots(String id) =>
-    _lowerCaseUnderScoreWithDots.hasMatch(id);
-
 /// Returns `true` if this [fileName] is a Pubspec file.
 bool isPubspecFileName(String fileName) => _pubspec.hasMatch(fileName);
 
-/// Returns `true` if the given code unit [c] is upper case.
-@deprecated // Never intended for public use.
-bool isUpperCase(int c) => c >= 0x40 && c <= 0x5A;
-
 class Spelunker {
   final String path;
   final IOSink sink;
diff --git a/pkg/analyzer/lib/src/manifest/manifest_warning_code.g.dart b/pkg/analyzer/lib/src/manifest/manifest_warning_code.g.dart
index 0e1ee4c..8ac1bdd 100644
--- a/pkg/analyzer/lib/src/manifest/manifest_warning_code.g.dart
+++ b/pkg/analyzer/lib/src/manifest/manifest_warning_code.g.dart
@@ -21,9 +21,14 @@
   static const ManifestWarningCode CAMERA_PERMISSIONS_INCOMPATIBLE =
       ManifestWarningCode(
     'CAMERA_PERMISSIONS_INCOMPATIBLE',
-    "Camera permissions make app incompatible for Chrome OS, consider adding optional features \"android.hardware.camera\" and \"android.hardware.camera.autofocus\".",
+    "Camera permissions make app incompatible for Chrome OS, consider adding "
+        "optional features \"android.hardware.camera\" and "
+        "\"android.hardware.camera.autofocus\".",
     correctionMessage:
-        "Try adding `<uses-feature android:name=\"android.hardware.camera\"  android:required=\"false\">` `<uses-feature android:name=\"android.hardware.camera.autofocus\"  android:required=\"false\">`.",
+        "Try adding `<uses-feature android:name=\"android.hardware.camera\"  "
+        "android:required=\"false\">` `<uses-feature "
+        "android:name=\"android.hardware.camera.autofocus\"  "
+        "android:required=\"false\">`.",
   );
 
   /**
@@ -31,9 +36,11 @@
    */
   static const ManifestWarningCode NON_RESIZABLE_ACTIVITY = ManifestWarningCode(
     'NON_RESIZABLE_ACTIVITY',
-    "The `<activity>` element should be allowed to be resized to allow users to take advantage of the multi-window environment on Chrome OS",
+    "The `<activity>` element should be allowed to be resized to allow users "
+        "to take advantage of the multi-window environment on Chrome OS",
     correctionMessage:
-        "Consider declaring the corresponding activity element with `resizableActivity=\"true\"` attribute.",
+        "Consider declaring the corresponding activity element with "
+        "`resizableActivity=\"true\"` attribute.",
   );
 
   /**
@@ -42,9 +49,11 @@
    */
   static const ManifestWarningCode NO_TOUCHSCREEN_FEATURE = ManifestWarningCode(
     'NO_TOUCHSCREEN_FEATURE',
-    "The default \"android.hardware.touchscreen\" needs to be optional for Chrome OS. ",
-    correctionMessage:
-        "Consider adding <uses-feature android:name=\"android.hardware.touchscreen\" android:required=\"false\" /> to the manifest.",
+    "The default \"android.hardware.touchscreen\" needs to be optional for "
+        "Chrome OS. ",
+    correctionMessage: "Consider adding <uses-feature "
+        "android:name=\"android.hardware.touchscreen\" android:required=\"false\" "
+        "/> to the manifest.",
   );
 
   /**
@@ -54,9 +63,10 @@
   static const ManifestWarningCode PERMISSION_IMPLIES_UNSUPPORTED_HARDWARE =
       ManifestWarningCode(
     'PERMISSION_IMPLIES_UNSUPPORTED_HARDWARE',
-    "Permission makes app incompatible for Chrome OS, consider adding optional {0} feature tag, ",
-    correctionMessage:
-        " Try adding `<uses-feature android:name=\"{0}\"  android:required=\"false\">`.",
+    "Permission makes app incompatible for Chrome OS, consider adding optional "
+        "{0} feature tag, ",
+    correctionMessage: " Try adding `<uses-feature android:name=\"{0}\"  "
+        "android:required=\"false\">`.",
   );
 
   /**
@@ -65,9 +75,12 @@
   static const ManifestWarningCode SETTING_ORIENTATION_ON_ACTIVITY =
       ManifestWarningCode(
     'SETTING_ORIENTATION_ON_ACTIVITY',
-    "The `<activity>` element should not be locked to any orientation so that users can take advantage of the multi-window environments and larger screens on Chrome OS",
+    "The `<activity>` element should not be locked to any orientation so that "
+        "users can take advantage of the multi-window environments and larger "
+        "screens on Chrome OS",
     correctionMessage:
-        "Consider declaring the corresponding activity element with `screenOrientation=\"unspecified\"` or `\"fullSensor\"` attribute.",
+        "Consider declaring the corresponding activity element with "
+        "`screenOrientation=\"unspecified\"` or `\"fullSensor\"` attribute.",
   );
 
   /**
@@ -76,7 +89,8 @@
   static const ManifestWarningCode UNSUPPORTED_CHROME_OS_FEATURE =
       ManifestWarningCode(
     'UNSUPPORTED_CHROME_OS_FEATURE',
-    "The feature {0} isn't supported on Chrome OS, consider making it optional.",
+    "The feature {0} isn't supported on Chrome OS, consider making it "
+        "optional.",
     correctionMessage:
         "Try changing to `android:required=\"false\"` for this feature.",
   );
@@ -88,7 +102,8 @@
   static const ManifestWarningCode UNSUPPORTED_CHROME_OS_HARDWARE =
       ManifestWarningCode(
     'UNSUPPORTED_CHROME_OS_HARDWARE',
-    "The feature {0} isn't supported on Chrome OS, consider making it optional.",
+    "The feature {0} isn't supported on Chrome OS, consider making it "
+        "optional.",
     correctionMessage:
         "Try adding `android:required=\"false\"` for this feature.",
   );
diff --git a/pkg/analyzer/lib/src/pubspec/pubspec_warning_code.g.dart b/pkg/analyzer/lib/src/pubspec/pubspec_warning_code.g.dart
index 88d2f07..e1565ec 100644
--- a/pkg/analyzer/lib/src/pubspec/pubspec_warning_code.g.dart
+++ b/pkg/analyzer/lib/src/pubspec/pubspec_warning_code.g.dart
@@ -120,7 +120,8 @@
   // ```
   static const PubspecWarningCode ASSET_FIELD_NOT_LIST = PubspecWarningCode(
     'ASSET_FIELD_NOT_LIST',
-    "The value of the 'asset' field is expected to be a list of relative file paths.",
+    "The value of the 'asset' field is expected to be a list of relative file "
+        "paths.",
     correctionMessage:
         "Try converting the value to be a list of relative file paths.",
     hasPublishedDocs: true,
@@ -337,7 +338,8 @@
     'INVALID_DEPENDENCY',
     "Publishable packages can't have '{0}' dependencies.",
     correctionMessage:
-        "Try adding a 'publish_to: none' entry to mark the package as not for publishing or remove the {0} dependency.",
+        "Try adding a 'publish_to: none' entry to mark the package as not for "
+        "publishing or remove the {0} dependency.",
     hasPublishedDocs: true,
   );
 
@@ -518,7 +520,8 @@
     'PATH_PUBSPEC_DOES_NOT_EXIST',
     "The directory '{0}' doesn't contain a pubspec.",
     correctionMessage:
-        "Try creating a pubspec in the referenced directory or using a path that has a pubspec.",
+        "Try creating a pubspec in the referenced directory or using a path "
+        "that has a pubspec.",
     hasPublishedDocs: true,
   );
 
@@ -561,7 +564,8 @@
   static const PubspecWarningCode UNNECESSARY_DEV_DEPENDENCY =
       PubspecWarningCode(
     'UNNECESSARY_DEV_DEPENDENCY',
-    "The dev dependency on {0} is unnecessary because there is also a normal dependency on that package.",
+    "The dev dependency on {0} is unnecessary because there is also a normal "
+        "dependency on that package.",
     correctionMessage: "Try removing the dev dependency.",
     hasPublishedDocs: true,
   );
diff --git a/pkg/analyzer/lib/src/summary/package_bundle_reader.dart b/pkg/analyzer/lib/src/summary/package_bundle_reader.dart
index 99372ae..a332f28 100644
--- a/pkg/analyzer/lib/src/summary/package_bundle_reader.dart
+++ b/pkg/analyzer/lib/src/summary/package_bundle_reader.dart
@@ -90,11 +90,9 @@
 /// The [UriResolver] that knows about sources that are served from their
 /// summaries.
 class InSummaryUriResolver extends UriResolver {
-  /// TODO(scheglov) Remove it, we don't need it.
-  ResourceProvider? resourceProvider;
   final SummaryDataStore _dataStore;
 
-  InSummaryUriResolver(this.resourceProvider, this._dataStore);
+  InSummaryUriResolver(this._dataStore);
 
   @override
   Uri? pathToUri(String path) => null;
diff --git a/pkg/analyzer/lib/src/summary/summary_file_builder.dart b/pkg/analyzer/lib/src/summary/summary_file_builder.dart
deleted file mode 100644
index 521f24b..0000000
--- a/pkg/analyzer/lib/src/summary/summary_file_builder.dart
+++ /dev/null
@@ -1,27 +0,0 @@
-// Copyright (c) 2016, the Dart project authors. Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-@Deprecated('Use package:analyzer/dart/sdk/build_sdk_summary.dart instead')
-library summary_file_builder;
-
-import 'dart:typed_data';
-
-import 'package:analyzer/dart/sdk/build_sdk_summary.dart' as api;
-import 'package:analyzer/file_system/file_system.dart';
-
-/// Build summary for SDK the at the given [sdkPath].
-///
-/// If [embedderYamlPath] is provided, then libraries from this file are
-/// appended to the libraries of the specified SDK.
-Uint8List buildSdkSummary({
-  required ResourceProvider resourceProvider,
-  required String sdkPath,
-  String? embedderYamlPath,
-}) {
-  return api.buildSdkSummary(
-    resourceProvider: resourceProvider,
-    sdkPath: sdkPath,
-    embedderYamlPath: embedderYamlPath,
-  );
-}
diff --git a/pkg/analyzer/lib/src/summary/summary_sdk.dart b/pkg/analyzer/lib/src/summary/summary_sdk.dart
index e53670d..bb34ac0 100644
--- a/pkg/analyzer/lib/src/summary/summary_sdk.dart
+++ b/pkg/analyzer/lib/src/summary/summary_sdk.dart
@@ -2,7 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'package:analyzer/file_system/file_system.dart' show ResourceProvider;
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/generated/source.dart' show Source;
 import 'package:analyzer/src/summary/package_bundle_reader.dart';
@@ -14,29 +13,15 @@
 /// suitable only for command-line tools, but not for IDEs - it does not
 /// implement [sdkLibraries], [uris] and [fromFileUri].
 class SummaryBasedDartSdk implements DartSdk {
-  late final PackageBundleReader _bundle;
-  late final SummaryDataStore _dataStore;
+  final PackageBundleReader _bundle;
   late final InSummaryUriResolver _uriResolver;
 
-  /// TODO(scheglov) Remove it when the default constructor.
-  ResourceProvider? resourceProvider;
-
-  @Deprecated('Use SummaryBasedDartSdk.forBundle() instead')
-  SummaryBasedDartSdk(String summaryPath, bool _, {this.resourceProvider}) {
-    _dataStore = SummaryDataStore(<String>[summaryPath],
-        resourceProvider: resourceProvider);
-    _uriResolver = InSummaryUriResolver(resourceProvider, _dataStore);
-    _bundle = _dataStore.bundles.single;
-  }
-
-  SummaryBasedDartSdk.forBundle(PackageBundleReader bundle) {
-    _bundle = bundle;
-
-    _dataStore = SummaryDataStore([]);
+  SummaryBasedDartSdk.forBundle(this._bundle) {
+    var dataStore = SummaryDataStore([]);
     // TODO(scheglov) We need a solution to avoid these paths at all.
-    _dataStore.addBundle('', bundle);
+    dataStore.addBundle('', bundle);
 
-    _uriResolver = InSummaryUriResolver(resourceProvider, _dataStore);
+    _uriResolver = InSummaryUriResolver(dataStore);
   }
 
   @override
diff --git a/pkg/analyzer/lib/src/summary2/ast_text_printer.dart b/pkg/analyzer/lib/src/summary2/ast_text_printer.dart
index b763df3..b30141a 100644
--- a/pkg/analyzer/lib/src/summary2/ast_text_printer.dart
+++ b/pkg/analyzer/lib/src/summary2/ast_text_printer.dart
@@ -145,6 +145,7 @@
   void visitClassDeclaration(ClassDeclaration node) {
     _compilationUnitMember(node);
     _token(node.abstractKeyword);
+    _token(node.macroKeyword);
     _token(node.classKeyword);
     node.name.accept(this);
     node.typeParameters?.accept(this);
@@ -161,6 +162,7 @@
   void visitClassTypeAlias(ClassTypeAlias node) {
     _compilationUnitMember(node);
     _token(node.abstractKeyword);
+    _token(node.macroKeyword);
     _token(node.typedefKeyword);
     node.name.accept(this);
     node.typeParameters?.accept(this);
diff --git a/pkg/analyzer/lib/src/summary2/bundle_reader.dart b/pkg/analyzer/lib/src/summary2/bundle_reader.dart
index e331093..14aa0a2 100644
--- a/pkg/analyzer/lib/src/summary2/bundle_reader.dart
+++ b/pkg/analyzer/lib/src/summary2/bundle_reader.dart
@@ -161,6 +161,7 @@
     );
     reader._addFormalParameters(element.parameters);
     _readFormalParameters(reader, element.parameters);
+    element.superConstructor = reader.readElement() as ConstructorElement?;
     element.redirectedConstructor = reader.readElement() as ConstructorElement?;
     element.constantInitializers = reader._readNodeList();
     applyConstantOffsets?.perform();
@@ -942,6 +943,7 @@
     return List.generate(length, (_) {
       var name = _reader.readStringReference();
       var isInitializingFormal = _reader.readBool();
+      var isSuperFormal = _reader.readBool();
       var reference = containerRef.getChild(name);
 
       var kindIndex = _reader.readByte();
@@ -955,6 +957,12 @@
             nameOffset: -1,
             parameterKind: kind,
           );
+        } else if (isSuperFormal) {
+          element = SuperFormalParameterElementImpl(
+            name: name,
+            nameOffset: -1,
+            parameterKind: kind,
+          );
         } else {
           element = ParameterElementImpl(
             name: name,
@@ -969,6 +977,12 @@
             nameOffset: -1,
             parameterKind: kind,
           );
+        } else if (isSuperFormal) {
+          element = DefaultSuperFormalParameterElementImpl(
+            name: name,
+            nameOffset: -1,
+            parameterKind: kind,
+          );
         } else {
           element = DefaultParameterElementImpl(
             name: name,
diff --git a/pkg/analyzer/lib/src/summary2/bundle_writer.dart b/pkg/analyzer/lib/src/summary2/bundle_writer.dart
index f6fdf85..946fd6e6 100644
--- a/pkg/analyzer/lib/src/summary2/bundle_writer.dart
+++ b/pkg/analyzer/lib/src/summary2/bundle_writer.dart
@@ -162,6 +162,7 @@
 
     _resolutionSink.localElements.withElements(element.parameters, () {
       _writeList(element.parameters, _writeParameterElement);
+      _resolutionSink.writeElement(element.superConstructor);
       _resolutionSink.writeElement(element.redirectedConstructor);
       _resolutionSink._writeNodeList(element.constantInitializers);
     });
@@ -173,7 +174,8 @@
     _sink._writeStringReference(element.name);
     _resolutionSink._writeAnnotationList(element.metadata);
 
-    var constants = element.fields.where((e) => !e.isSynthetic).toList();
+    var constants =
+        element.fields.whereType<ConstFieldElementImpl_EnumValue>().toList();
     _writeList<FieldElement>(constants, (field) {
       _sink._writeStringReference(field.name);
       _resolutionSink._writeAnnotationList(field.metadata);
@@ -334,6 +336,7 @@
     element as ParameterElementImpl;
     _sink._writeStringReference(element.name);
     _sink.writeBool(element.isInitializingFormal);
+    _sink.writeBool(element.isSuperFormal);
     _sink._writeFormalParameterKind(element);
     ParameterElementFlags.write(_sink, element);
 
diff --git a/pkg/analyzer/lib/src/summary2/element_builder.dart b/pkg/analyzer/lib/src/summary2/element_builder.dart
index 8d6599b..f0d5965 100644
--- a/pkg/analyzer/lib/src/summary2/element_builder.dart
+++ b/pkg/analyzer/lib/src/summary2/element_builder.dart
@@ -352,13 +352,12 @@
       _enclosingContext.addParameter(null, element);
     }
     element.hasImplicitType = node.type == null && node.parameters == null;
-    element.isExplicitlyCovariant = node.covariantKeyword != null;
-    element.isFinal = node.isFinal;
     element.metadata = _buildAnnotations(node.metadata);
     _setCodeRange(element, node);
 
     nameNode.staticElement = element;
 
+    // TODO(scheglov) check that we don't set reference for parameters
     var fakeReference = Reference.root();
     var holder = _EnclosingContext(fakeReference, element);
     _withEnclosing(holder, () {
@@ -794,6 +793,59 @@
   }
 
   @override
+  void visitSuperFormalParameter(
+    covariant SuperFormalParameterImpl node,
+  ) {
+    var nameNode = node.identifier;
+    var name = nameNode.name;
+    var nameOffset = nameNode.offset;
+
+    SuperFormalParameterElementImpl element;
+    var parent = node.parent;
+    if (parent is DefaultFormalParameter) {
+      element = DefaultSuperFormalParameterElementImpl(
+        name: name,
+        nameOffset: nameOffset,
+        parameterKind: node.kind,
+      )..constantInitializer = parent.defaultValue;
+      _linker.elementNodes[element] = parent;
+      _enclosingContext.addParameter(name, element);
+    } else {
+      element = SuperFormalParameterElementImpl(
+        name: name,
+        nameOffset: nameOffset,
+        parameterKind: node.kind,
+      );
+      _linker.elementNodes[element] = node;
+      _enclosingContext.addParameter(null, element);
+    }
+    element.hasImplicitType = node.type == null && node.parameters == null;
+    element.metadata = _buildAnnotations(node.metadata);
+    _setCodeRange(element, node);
+
+    nameNode.staticElement = element;
+
+    // TODO(scheglov) check that we don't set reference for parameters
+    var fakeReference = Reference.root();
+    var holder = _EnclosingContext(fakeReference, element);
+    _withEnclosing(holder, () {
+      var formalParameters = node.parameters;
+      if (formalParameters != null) {
+        formalParameters.accept(this);
+        element.parameters = holder.parameters;
+      }
+
+      var typeParameters = node.typeParameters;
+      if (typeParameters != null) {
+        typeParameters.accept(this);
+        element.typeParameters = holder.typeParameters;
+      }
+    });
+
+    _buildType(node.type);
+  }
+
+  @override
   void visitTopLevelVariableDeclaration(
     covariant TopLevelVariableDeclarationImpl node,
   ) {
@@ -905,15 +957,14 @@
     element.fields = holder.properties.whereType<FieldElement>().toList();
     element.methods = holder.methods;
 
-    var constructors = holder.constructors;
-    if (constructors.isEmpty) {
-      var containerRef = element.reference!.getChild('@constructor');
-      constructors = [
-        ConstructorElementImpl('', -1)
-          ..isSynthetic = true
-          ..reference = containerRef.getChild(''),
-      ];
+    if (holder.constructors.isEmpty) {
+      holder.addConstructor(
+        '',
+        ConstructorElementImpl('', -1)..isSynthetic = true,
+      );
     }
+
+    var constructors = holder.constructors;
     element.constructors = constructors;
 
     // We have all fields and constructors.
@@ -1009,7 +1060,7 @@
     var absoluteUri = resolveRelativeUri(_libraryBuilder.uri, relativeUri);
 
     var sourceFactory = _linker.analysisContext.sourceFactory;
-    return rewriteFileToPackageUri(sourceFactory, absoluteUri);
+    return rewriteToCanonicalUri(sourceFactory, absoluteUri);
   }
 
   LibraryElement? _selectLibrary(NamespaceDirective node) {
diff --git a/pkg/analyzer/lib/src/summary2/link.dart b/pkg/analyzer/lib/src/summary2/link.dart
index d605919..cf733cc 100644
--- a/pkg/analyzer/lib/src/summary2/link.dart
+++ b/pkg/analyzer/lib/src/summary2/link.dart
@@ -17,6 +17,7 @@
 import 'package:analyzer/src/summary2/linked_element_factory.dart';
 import 'package:analyzer/src/summary2/reference.dart';
 import 'package:analyzer/src/summary2/simply_bounded.dart';
+import 'package:analyzer/src/summary2/super_constructor_resolver.dart';
 import 'package:analyzer/src/summary2/top_level_inference.dart';
 import 'package:analyzer/src/summary2/type_alias.dart';
 import 'package:analyzer/src/summary2/types_builder.dart';
@@ -89,6 +90,7 @@
     _createTypeSystem();
     _buildEnumChildren();
     _resolveTypes();
+    SuperConstructorResolver(this).perform();
     _performTopLevelInference();
     _resolveConstructors();
     _resolveConstantInitializers();
diff --git a/pkg/analyzer/lib/src/summary2/metadata_resolver.dart b/pkg/analyzer/lib/src/summary2/metadata_resolver.dart
index 3bf8d56..286730c 100644
--- a/pkg/analyzer/lib/src/summary2/metadata_resolver.dart
+++ b/pkg/analyzer/lib/src/summary2/metadata_resolver.dart
@@ -203,6 +203,12 @@
   }
 
   @override
+  void visitSuperFormalParameter(SuperFormalParameter node) {
+    node.metadata.accept(this);
+    node.parameters?.accept(this);
+  }
+
+  @override
   void visitTopLevelVariableDeclaration(TopLevelVariableDeclaration node) {
     node.metadata.accept(this);
   }
diff --git a/pkg/analyzer/lib/src/summary2/reference_resolver.dart b/pkg/analyzer/lib/src/summary2/reference_resolver.dart
index 6e6cbe2..4208e83 100644
--- a/pkg/analyzer/lib/src/summary2/reference_resolver.dart
+++ b/pkg/analyzer/lib/src/summary2/reference_resolver.dart
@@ -376,6 +376,22 @@
   }
 
   @override
+  void visitSuperFormalParameter(SuperFormalParameter node) {
+    var outerScope = scope;
+
+    var element = node.declaredElement as SuperFormalParameterElementImpl;
+
+    scope = TypeParameterScope(scope, element.typeParameters);
+
+    node.type?.accept(this);
+    node.typeParameters?.accept(this);
+    node.parameters?.accept(this);
+    nodesToBuildType.addDeclaration(node);
+
+    scope = outerScope;
+  }
+
+  @override
   void visitTopLevelVariableDeclaration(TopLevelVariableDeclaration node) {
     node.variables.accept(this);
   }
diff --git a/pkg/analyzer/lib/src/summary2/super_constructor_resolver.dart b/pkg/analyzer/lib/src/summary2/super_constructor_resolver.dart
new file mode 100644
index 0000000..694f27d
--- /dev/null
+++ b/pkg/analyzer/lib/src/summary2/super_constructor_resolver.dart
@@ -0,0 +1,65 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/element/element.dart';
+import 'package:analyzer/src/dart/element/element.dart';
+import 'package:analyzer/src/summary2/link.dart';
+import 'package:collection/collection.dart';
+
+/// Resolves the explicit or implicit super-constructors invoked by
+/// non-redirecting generative constructors.
+class SuperConstructorResolver {
+  final Linker _linker;
+
+  SuperConstructorResolver(this._linker);
+
+  void perform() {
+    for (var builder in _linker.builders.values) {
+      for (var unitElement in builder.element.units) {
+        for (var classElement in unitElement.classes) {
+          for (var constructorElement in classElement.constructors) {
+            _constructor(classElement, constructorElement);
+          }
+        }
+      }
+    }
+  }
+
+  void _constructor(ClassElement classElement, ConstructorElement element) {
+    element as ConstructorElementImpl;
+
+    // Constructors of mixin applications are already configured.
+    if (classElement.isMixinApplication) {
+      return;
+    }
+
+    // We handle only generative constructors here.
+    if (element.isFactory) {
+      return;
+    }
+
+    var invokesDefaultSuperConstructor = true;
+    var node = _linker.getLinkingNode(element);
+    if (node is ConstructorDeclaration) {
+      for (var initializer in node.initializers) {
+        if (initializer is RedirectingConstructorInvocation) {
+          invokesDefaultSuperConstructor = false;
+        } else if (initializer is SuperConstructorInvocation) {
+          invokesDefaultSuperConstructor = false;
+          var name = initializer.constructorName?.name ?? '';
+          element.superConstructor = classElement.supertype?.constructors
+              .where((element) => element.name == name)
+              .firstOrNull;
+        }
+      }
+    }
+
+    if (invokesDefaultSuperConstructor) {
+      element.superConstructor = classElement.supertype?.constructors
+          .where((element) => element.name.isEmpty)
+          .firstOrNull;
+    }
+  }
+}
diff --git a/pkg/analyzer/lib/src/summary2/top_level_inference.dart b/pkg/analyzer/lib/src/summary2/top_level_inference.dart
index 6640e26..714e348 100644
--- a/pkg/analyzer/lib/src/summary2/top_level_inference.dart
+++ b/pkg/analyzer/lib/src/summary2/top_level_inference.dart
@@ -141,7 +141,8 @@
 class _ConstructorInferenceNode extends _InferenceNode {
   final _InferenceWalker _walker;
   final ConstructorElement _constructor;
-  final List<_FieldFormalParameterWithField> _parameters = [];
+  final List<_FieldFormalParameter> _fieldParameters = [];
+  final List<_SuperFormalParameter> _superParameters = [];
 
   /// If this node is a constructor of a mixin application, this field
   /// is the corresponding constructor of the superclass.
@@ -156,8 +157,17 @@
         if (parameter.hasImplicitType) {
           var field = parameter.field;
           if (field != null) {
-            _parameters.add(
-              _FieldFormalParameterWithField(parameter, field),
+            _fieldParameters.add(
+              _FieldFormalParameter(parameter, field),
+            );
+          }
+        }
+      } else if (parameter is SuperFormalParameterElementImpl) {
+        if (parameter.hasImplicitType) {
+          var superParameter = parameter.superConstructorParameter;
+          if (superParameter != null) {
+            _superParameters.add(
+              _SuperFormalParameter(parameter, superParameter),
             );
           }
         }
@@ -187,10 +197,12 @@
 
   @override
   List<_InferenceNode> computeDependencies() {
-    var dependencies = _parameters
-        .map((e) => _walker.getNode(e.field))
-        .whereNotNull()
-        .toList();
+    var dependencies = [
+      ..._fieldParameters.map((e) => _walker.getNode(e.field)).whereNotNull(),
+      ..._superParameters
+          .map((e) => _walker.getNode(e.superParameter))
+          .whereNotNull(),
+    ];
 
     dependencies.addIfNotNull(
       _walker.getNode(_baseConstructor?.element),
@@ -201,9 +213,11 @@
 
   @override
   void evaluate() {
-    for (var parameterWithField in _parameters) {
-      var parameter = parameterWithField.parameter;
-      parameter.type = parameterWithField.field.type;
+    for (var fieldParameter in _fieldParameters) {
+      fieldParameter.parameter.type = fieldParameter.field.type;
+    }
+    for (var superParameter in _superParameters) {
+      superParameter.parameter.type = superParameter.superParameter.type;
     }
 
     // We have inferred formal parameter types of the base constructor.
@@ -241,20 +255,22 @@
 
   @override
   void markCircular(List<_InferenceNode> cycle) {
-    for (var parameterWithField in _parameters) {
-      var parameter = parameterWithField.parameter;
-      parameter.type = DynamicTypeImpl.instance;
+    for (var fieldParameter in _fieldParameters) {
+      fieldParameter.parameter.type = DynamicTypeImpl.instance;
+    }
+    for (var superParameter in _superParameters) {
+      superParameter.parameter.type = DynamicTypeImpl.instance;
     }
     isEvaluated = true;
   }
 }
 
 /// A field formal parameter with a non-nullable field.
-class _FieldFormalParameterWithField {
+class _FieldFormalParameter {
   final FieldFormalParameterElementImpl parameter;
   final FieldElement field;
 
-  _FieldFormalParameterWithField(this.parameter, this.field);
+  _FieldFormalParameter(this.parameter, this.field);
 }
 
 class _InferenceDependenciesCollector extends RecursiveAstVisitor<void> {
@@ -408,6 +424,14 @@
   }
 }
 
+/// A super formal parameter with a non-nullable super-constructor parameter.
+class _SuperFormalParameter {
+  final SuperFormalParameterElementImpl parameter;
+  final ParameterElement superParameter;
+
+  _SuperFormalParameter(this.parameter, this.superParameter);
+}
+
 class _VariableInferenceNode extends _InferenceNode {
   final _InferenceWalker _walker;
   final CompilationUnitElementImpl _unitElement;
diff --git a/pkg/analyzer/lib/src/summary2/types_builder.dart b/pkg/analyzer/lib/src/summary2/types_builder.dart
index 9887d9c..53b27e3 100644
--- a/pkg/analyzer/lib/src/summary2/types_builder.dart
+++ b/pkg/analyzer/lib/src/summary2/types_builder.dart
@@ -206,6 +206,8 @@
     } else if (node is SimpleFormalParameter) {
       var element = node.declaredElement as ParameterElementImpl;
       element.type = node.type?.type ?? _dynamicType;
+    } else if (node is SuperFormalParameter) {
+      _superFormalParameter(node);
     } else if (node is VariableDeclarationList) {
       var type = node.type?.type;
       if (type != null) {
@@ -310,6 +312,22 @@
     }
   }
 
+  void _superFormalParameter(SuperFormalParameter node) {
+    var element = node.declaredElement as SuperFormalParameterElementImpl;
+    var parameterList = node.parameters;
+    if (parameterList != null) {
+      var type = _buildFunctionType(
+        node.typeParameters,
+        node.type,
+        parameterList,
+        _nullability(node, node.question != null),
+      );
+      element.type = type;
+    } else {
+      element.type = node.type?.type ?? _dynamicType;
+    }
+  }
+
   List<TypeParameterElement> _typeParameters(TypeParameterList? node) {
     if (node == null) {
       return const <TypeParameterElement>[];
diff --git a/pkg/analyzer/lib/src/task/options.dart b/pkg/analyzer/lib/src/task/options.dart
index 73b4a73..682acc6 100644
--- a/pkg/analyzer/lib/src/task/options.dart
+++ b/pkg/analyzer/lib/src/task/options.dart
@@ -10,7 +10,6 @@
 import 'package:analyzer/src/analysis_options/error/option_codes.dart';
 import 'package:analyzer/src/dart/analysis/experiments.dart';
 import 'package:analyzer/src/generated/engine.dart';
-import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/utilities_general.dart';
 import 'package:analyzer/src/lint/config.dart';
@@ -365,7 +364,7 @@
 
   /// Pretty String listing legal values.
   static final String legalValueString =
-      StringUtilities.printListOfQuotedNames(legalValues);
+      legalValues.quotedAndCommaSeparatedWithAnd;
 
   /// Lazily populated set of error codes.
   static final Set<String> _errorCodes =
diff --git a/pkg/analyzer/lib/src/task/strong/checker.dart b/pkg/analyzer/lib/src/task/strong/checker.dart
index ef1119a..7c2569f 100644
--- a/pkg/analyzer/lib/src/task/strong/checker.dart
+++ b/pkg/analyzer/lib/src/task/strong/checker.dart
@@ -14,7 +14,6 @@
 import 'package:analyzer/error/listener.dart';
 import 'package:analyzer/src/dart/ast/extensions.dart';
 import 'package:analyzer/src/dart/element/element.dart';
-import 'package:analyzer/src/dart/element/inheritance_manager3.dart';
 import 'package:analyzer/src/dart/element/type.dart';
 import 'package:analyzer/src/dart/element/type_system.dart';
 import 'package:analyzer/src/error/codes.dart' show CompileTimeErrorCode;
@@ -37,18 +36,13 @@
 
 /// Checks the body of functions and properties.
 class CodeChecker extends RecursiveAstVisitor {
-  final TypeSystemImpl rules;
-  final TypeProvider typeProvider;
-  final InheritanceManager3 inheritance;
-  final AnalysisErrorListener reporter;
+  final TypeSystemImpl _typeSystem;
+  final TypeProvider _typeProvider;
+  final ErrorReporter _errorReporter;
 
   late final FeatureSet _featureSet;
 
-  CodeChecker(TypeProvider typeProvider, TypeSystemImpl rules, this.inheritance,
-      AnalysisErrorListener reporter)
-      : typeProvider = typeProvider,
-        rules = rules,
-        reporter = reporter;
+  CodeChecker(this._typeProvider, this._typeSystem, this._errorReporter);
 
   bool get _isNonNullableByDefault =>
       _featureSet.isEnabled(Feature.non_nullable);
@@ -97,11 +91,11 @@
     } else if (element is SpreadElement) {
       // Spread expression may be dynamic in which case it's implicitly downcast
       // to Iterable<dynamic>
-      DartType expressionCastType = typeProvider.iterableDynamicType;
+      DartType expressionCastType = _typeProvider.iterableDynamicType;
       checkAssignment(element.expression, expressionCastType);
 
       var exprType = element.expression.typeOrThrow;
-      var asIterableType = exprType.asInstanceOf(typeProvider.iterableElement);
+      var asIterableType = exprType.asInstanceOf(_typeProvider.iterableElement);
 
       if (asIterableType != null) {
         var elementType = asIterableType.typeArguments[0];
@@ -126,12 +120,12 @@
     } else if (element is SpreadElement) {
       // Spread expression may be dynamic in which case it's implicitly downcast
       // to Map<dynamic, dynamic>
-      DartType expressionCastType = typeProvider.mapType(
+      DartType expressionCastType = _typeProvider.mapType(
           DynamicTypeImpl.instance, DynamicTypeImpl.instance);
       checkAssignment(element.expression, expressionCastType);
 
       var exprType = element.expression.typeOrThrow;
-      var asMapType = exprType.asInstanceOf(typeProvider.mapElement);
+      var asMapType = exprType.asInstanceOf(_typeProvider.mapElement);
 
       if (asMapType != null) {
         var elementKeyType = asMapType.typeArguments[0];
@@ -450,7 +444,7 @@
 
       // Refine the return type.
       var rhsType = expr.rightHandSide.typeOrThrow;
-      var returnType = rules.refineBinaryExpressionType(
+      var returnType = _typeSystem.refineBinaryExpressionType(
         expr.readType!,
         op,
         rhsType,
@@ -491,20 +485,20 @@
     if (fromType is FunctionType) {
       from = fromType;
     } else if (fromType is InterfaceType) {
-      from = rules.getCallMethodType(fromType);
+      from = _typeSystem.getCallMethodType(fromType);
       callTearoff = true;
     }
     if (from == null) {
       return null; // unrelated
     }
 
-    if (rules.isSubtypeOf(from, to)) {
+    if (_typeSystem.isSubtypeOf(from, to)) {
       // Sound subtype.
       // However we may still need cast if we have a call tearoff.
       return callTearoff;
     }
 
-    if (rules.isSubtypeOf(to, from)) {
+    if (_typeSystem.isSubtypeOf(to, from)) {
       // Assignable, but needs cast.
       return true;
     }
@@ -568,8 +562,8 @@
 
       // Refine the return type.
       var functionType = element.type;
-      var rhsType = typeProvider.intType;
-      var returnType = rules.refineBinaryExpressionType(
+      var rhsType = _typeProvider.intType;
+      var returnType = _typeSystem.refineBinaryExpressionType(
         node.readType!,
         TokenType.PLUS,
         rhsType,
@@ -611,18 +605,18 @@
     if (body.isAsynchronous) {
       if (body.isGenerator) {
         // Stream<T> -> T
-        expectedElement = typeProvider.streamElement;
+        expectedElement = _typeProvider.streamElement;
       } else {
         // Future<T> -> FutureOr<T>
-        var typeArg = (type.element == typeProvider.futureElement)
+        var typeArg = (type.element == _typeProvider.futureElement)
             ? (type as InterfaceType).typeArguments[0]
-            : typeProvider.dynamicType;
-        return typeProvider.futureOrType(typeArg);
+            : _typeProvider.dynamicType;
+        return _typeProvider.futureOrType(typeArg);
       }
     } else {
       if (body.isGenerator) {
         // Iterable<T> -> T
-        expectedElement = typeProvider.iterableElement;
+        expectedElement = _typeProvider.iterableElement;
       } else {
         // T -> T
         return type;
@@ -632,7 +626,7 @@
       if (type.isDynamic) {
         // Ensure it's at least a Stream / Iterable.
         return expectedElement.instantiate(
-          typeArguments: [typeProvider.dynamicType],
+          typeArguments: [_typeProvider.dynamicType],
           nullabilitySuffix: _noneOrStarSuffix,
         );
       } else {
@@ -669,7 +663,7 @@
     if (type is FunctionType) {
       return type;
     } else if (type is InterfaceType) {
-      return rules.getCallMethodType(type);
+      return _typeSystem.getCallMethodType(type);
     }
     return null;
   }
@@ -692,12 +686,12 @@
     }
 
     // fromT <: toT, no coercion needed.
-    if (rules.isSubtypeOf(from, to)) {
+    if (_typeSystem.isSubtypeOf(from, to)) {
       return false;
     }
 
     // Down cast or legal sideways cast, coercion needed.
-    if (rules.isAssignableTo(from, to)) {
+    if (_typeSystem.isAssignableTo(from, to)) {
       return true;
     }
 
@@ -705,7 +699,7 @@
     // In this case, we're more permissive than assignability.
     if (to.isDartAsyncFutureOr) {
       var to1 = (to as InterfaceType).typeArguments[0];
-      var to2 = typeProvider.futureType(to1);
+      var to2 = _typeProvider.futureType(to1);
       return _needsImplicitCast(expr, to: to1, from: from) == true ||
           _needsImplicitCast(expr, to: to2, from: from) == true;
     }
@@ -728,9 +722,9 @@
       bool forSpreadValue = false}) {
     // If this is an implicit tearoff, we need to mark the cast, but we don't
     // want to warn if it's a legal subtype.
-    if (from is InterfaceType && rules.acceptsFunctionType(to)) {
-      var type = rules.getCallMethodType(from);
-      if (type != null && rules.isSubtypeOf(type, to)) {
+    if (from is InterfaceType && _typeSystem.acceptsFunctionType(to)) {
+      var type = _typeSystem.getCallMethodType(from);
+      if (type != null && _typeSystem.isSubtypeOf(type, to)) {
         return;
       }
     }
@@ -793,24 +787,23 @@
     }
   }
 
-  void _recordMessage(AstNode node, ErrorCode errorCode, List arguments) {
-    // TODO(brianwilkerson) Convert this class to use an ErrorReporter so that
-    //  the logic for converting types is in one place.
-    arguments = arguments.map((argument) {
-      if (argument is DartType) {
-        return argument.getDisplayString(withNullability: false);
-      } else {
-        return argument;
-      }
-    }).toList();
+  void _recordMessage(
+      AstNode node, ErrorCode errorCode, List<Object> arguments) {
+    var argumentStrings = [
+      for (var argument in arguments)
+        if (argument is DartType)
+          argument.getDisplayString(withNullability: false)
+        else
+          argument.toString(),
+    ];
 
     int begin = node is AnnotatedNode
         ? node.firstTokenAfterCommentAndMetadata.offset
         : node.offset;
     int length = node.end - begin;
     var source = (node.root as CompilationUnit).declaredElement!.source;
-    var error = AnalysisError(source, begin, length, errorCode, arguments);
-    reporter.onError(error);
+    _errorReporter.reportError(
+        AnalysisError(source, begin, length, errorCode, argumentStrings));
   }
 
   void _visitForEachParts(ForEachParts node, SimpleIdentifier loopVariable) {
@@ -832,8 +825,8 @@
     }
     // Find the element type of the sequence.
     var sequenceElement = awaitKeyword != null
-        ? typeProvider.streamElement
-        : typeProvider.iterableElement;
+        ? _typeProvider.streamElement
+        : _typeProvider.iterableElement;
     var iterableType = node.iterable.typeOrThrow;
     var elementType = _getInstanceTypeArgument(iterableType, sequenceElement);
 
@@ -842,11 +835,11 @@
     // we'll do a separate cast of the dynamic element to the variable's type.
     if (elementType == null) {
       var sequenceType = sequenceElement.instantiate(
-        typeArguments: [typeProvider.dynamicType],
+        typeArguments: [_typeProvider.dynamicType],
         nullabilitySuffix: _noneOrStarSuffix,
       );
 
-      if (rules.isSubtypeOf(sequenceType, iterableType)) {
+      if (_typeSystem.isSubtypeOf(sequenceType, iterableType)) {
         _recordImplicitCast(node.iterable, sequenceType, from: iterableType);
         elementType = DynamicTypeImpl.instance;
       }
diff --git a/pkg/analyzer/lib/src/test_utilities/find_element.dart b/pkg/analyzer/lib/src/test_utilities/find_element.dart
index 195647b..8a894ec 100644
--- a/pkg/analyzer/lib/src/test_utilities/find_element.dart
+++ b/pkg/analyzer/lib/src/test_utilities/find_element.dart
@@ -636,3 +636,14 @@
     return class_(name).unnamedConstructor!;
   }
 }
+
+extension ExecutableElementExtensions on ExecutableElement {
+  SuperFormalParameterElement superFormalParameter(String name) {
+    for (var parameter in parameters) {
+      if (parameter is SuperFormalParameterElement && parameter.name == name) {
+        return parameter;
+      }
+    }
+    throw StateError('Not found: $name');
+  }
+}
diff --git a/pkg/analyzer/lib/src/test_utilities/find_node.dart b/pkg/analyzer/lib/src/test_utilities/find_node.dart
index 3c22e00..b25d26f 100644
--- a/pkg/analyzer/lib/src/test_utilities/find_node.dart
+++ b/pkg/analyzer/lib/src/test_utilities/find_node.dart
@@ -27,6 +27,10 @@
     return result;
   }
 
+  AdjacentStrings adjacentStrings(String search) {
+    return _node(search, (n) => n is AdjacentStrings);
+  }
+
   Annotation annotation(String search) {
     return _node(search, (n) => n is Annotation);
   }
@@ -35,10 +39,18 @@
     return _node(search, (n) => true);
   }
 
+  ArgumentList argumentList(String search) {
+    return _node(search, (n) => n is ArgumentList);
+  }
+
   AsExpression as_(String search) {
     return _node(search, (n) => n is AsExpression);
   }
 
+  AssertStatement assertStatement(String search) {
+    return _node(search, (n) => n is AssertStatement);
+  }
+
   AssignmentExpression assignment(String search) {
     return _node(search, (n) => n is AssignmentExpression);
   }
@@ -55,6 +67,10 @@
     return _node(search, (n) => n is Block);
   }
 
+  BlockFunctionBody blockFunctionBody(String search) {
+    return _node(search, (n) => n is BlockFunctionBody);
+  }
+
   BooleanLiteral booleanLiteral(String search) {
     return _node(search, (n) => n is BooleanLiteral);
   }
@@ -83,6 +99,10 @@
     return _node(search, (n) => n is CollectionElement);
   }
 
+  Comment comment(String search) {
+    return _node(search, (n) => n is Comment);
+  }
+
   CommentReference commentReference(String search) {
     return _node(search, (n) => n is CommentReference);
   }
@@ -111,6 +131,10 @@
     return _node(search, (n) => n is ContinueStatement);
   }
 
+  DeclaredIdentifier declaredIdentifier(String search) {
+    return _node(search, (n) => n is DeclaredIdentifier);
+  }
+
   DefaultFormalParameter defaultParameter(String search) {
     return _node(search, (n) => n is DefaultFormalParameter);
   }
@@ -123,6 +147,10 @@
     return _node(search, (n) => n is DoubleLiteral);
   }
 
+  EnumConstantDeclaration enumConstantDeclaration(String search) {
+    return _node(search, (n) => n is EnumConstantDeclaration);
+  }
+
   EnumDeclaration enumDeclaration(String search) {
     return _node(search, (n) => n is EnumDeclaration);
   }
@@ -135,10 +163,18 @@
     return _node(search, (n) => n is Expression);
   }
 
+  ExpressionFunctionBody expressionFunctionBody(String search) {
+    return _node(search, (n) => n is ExpressionFunctionBody);
+  }
+
   ExpressionStatement expressionStatement(String search) {
     return _node(search, (n) => n is ExpressionStatement);
   }
 
+  ExtendsClause extendsClause(String search) {
+    return _node(search, (n) => n is ExtendsClause);
+  }
+
   ExtensionDeclaration extensionDeclaration(String search) {
     return _node(search, (n) => n is ExtensionDeclaration);
   }
@@ -155,6 +191,26 @@
     return _node(search, (n) => n is FieldFormalParameter);
   }
 
+  ForEachPartsWithDeclaration forEachPartsWithDeclaration(String search) {
+    return _node(search, (n) => n is ForEachPartsWithDeclaration);
+  }
+
+  ForEachPartsWithIdentifier forEachPartsWithIdentifier(String search) {
+    return _node(search, (n) => n is ForEachPartsWithIdentifier);
+  }
+
+  FormalParameterList formalParameterList(String search) {
+    return _node(search, (n) => n is FormalParameterList);
+  }
+
+  ForPartsWithDeclarations forPartsWithDeclarations(String search) {
+    return _node(search, (n) => n is ForPartsWithDeclarations);
+  }
+
+  ForPartsWithExpression forPartsWithExpression(String search) {
+    return _node(search, (n) => n is ForPartsWithExpression);
+  }
+
   ForStatement forStatement(String search) {
     return _node(search, (n) => n is ForStatement);
   }
@@ -167,6 +223,10 @@
     return _node(search, (n) => n is FunctionDeclaration);
   }
 
+  FunctionDeclarationStatement functionDeclarationStatement(String search) {
+    return _node(search, (n) => n is FunctionDeclarationStatement);
+  }
+
   FunctionExpression functionExpression(String search) {
     return _node(search, (n) => n is FunctionExpression);
   }
@@ -195,6 +255,10 @@
     return _node(search, (n) => n is GenericTypeAlias);
   }
 
+  HideCombinator hideCombinator(String search) {
+    return _node(search, (n) => n is HideCombinator);
+  }
+
   IfElement ifElement(String search) {
     return _node(search, (n) => n is IfElement);
   }
@@ -203,6 +267,10 @@
     return _node(search, (n) => n is IfStatement);
   }
 
+  ImplementsClause implementsClause(String search) {
+    return _node(search, (n) => n is ImplementsClause);
+  }
+
   ImplicitCallReference implicitCallReference(String search) {
     return _node(search, (n) => n is ImplicitCallReference);
   }
@@ -223,6 +291,10 @@
     return _node(search, (n) => n is IntegerLiteral);
   }
 
+  InterpolationExpression interpolationExpression(String search) {
+    return _node(search, (n) => n is InterpolationExpression);
+  }
+
   IsExpression isExpression(String search) {
     return _node(search, (n) => n is IsExpression);
   }
@@ -231,14 +303,26 @@
     return _node(search, (n) => n is Label);
   }
 
+  LabeledStatement labeledStatement(String search) {
+    return _node(search, (n) => n is LabeledStatement);
+  }
+
   LibraryDirective library(String search) {
     return _node(search, (n) => n is LibraryDirective);
   }
 
+  LibraryIdentifier libraryIdentifier(String search) {
+    return _node(search, (n) => n is LibraryIdentifier);
+  }
+
   ListLiteral listLiteral(String search) {
     return _node(search, (n) => n is ListLiteral);
   }
 
+  MapLiteralEntry mapLiteralEntry(String search) {
+    return _node(search, (n) => n is MapLiteralEntry);
+  }
+
   MethodDeclaration methodDeclaration(String search) {
     return _node(search, (n) => n is MethodDeclaration);
   }
@@ -263,6 +347,14 @@
     return _node(search, (n) => n is NamedType);
   }
 
+  NativeClause nativeClause(String search) {
+    return _node(search, (n) => n is NativeClause);
+  }
+
+  NativeFunctionBody nativeFunctionBody(String search) {
+    return _node(search, (n) => n is NativeFunctionBody);
+  }
+
   NullLiteral nullLiteral(String search) {
     return _node(search, (n) => n is NullLiteral);
   }
@@ -308,18 +400,35 @@
     return _node(search, (n) => n is PropertyAccess);
   }
 
+  RedirectingConstructorInvocation redirectingConstructorInvocation(
+      String search) {
+    return _node(search, (n) => n is RedirectingConstructorInvocation);
+  }
+
   RethrowExpression rethrow_(String search) {
     return _node(search, (n) => n is RethrowExpression);
   }
 
+  ReturnStatement returnStatement(String search) {
+    return _node(search, (n) => n is ReturnStatement);
+  }
+
   SetOrMapLiteral setOrMapLiteral(String search) {
     return _node(search, (n) => n is SetOrMapLiteral);
   }
 
+  ShowCombinator showCombinator(String search) {
+    return _node(search, (n) => n is ShowCombinator);
+  }
+
   SimpleIdentifier simple(String search) {
     return _node(search, (_) => true);
   }
 
+  SimpleFormalParameter simpleFormalParameter(String search) {
+    return _node(search, (n) => n is SimpleFormalParameter);
+  }
+
   SimpleFormalParameter simpleParameter(String search) {
     return _node(search, (n) => n is SimpleFormalParameter);
   }
@@ -348,6 +457,14 @@
     return _node(search, (n) => n is SuperFormalParameter);
   }
 
+  SwitchCase switchCase(String search) {
+    return _node(search, (n) => n is SwitchCase);
+  }
+
+  SwitchDefault switchDefault(String search) {
+    return _node(search, (n) => n is SwitchDefault);
+  }
+
   SwitchStatement switchStatement(String search) {
     return _node(search, (n) => n is SwitchStatement);
   }
@@ -381,10 +498,18 @@
     throw StateError('$name');
   }
 
+  TryStatement tryStatement(String search) {
+    return _node(search, (n) => n is TryStatement);
+  }
+
   TypeAnnotation typeAnnotation(String search) {
     return _node(search, (n) => n is TypeAnnotation);
   }
 
+  TypeArgumentList typeArgumentList(String search) {
+    return _node(search, (n) => n is TypeArgumentList);
+  }
+
   TypedLiteral typedLiteral(String search) {
     return _node(search, (n) => n is TypedLiteral);
   }
@@ -397,6 +522,10 @@
     return _node(search, (n) => n is TypeParameter);
   }
 
+  TypeParameterList typeParameterList(String search) {
+    return _node(search, (n) => n is TypeParameterList);
+  }
+
   VariableDeclaration variableDeclaration(String search) {
     return _node(search, (n) => n is VariableDeclaration);
   }
@@ -405,10 +534,22 @@
     return _node(search, (n) => n is VariableDeclarationList);
   }
 
+  VariableDeclarationStatement variableDeclarationStatement(String search) {
+    return _node(search, (n) => n is VariableDeclarationStatement);
+  }
+
   WhileStatement whileStatement(String search) {
     return _node(search, (n) => n is WhileStatement);
   }
 
+  WithClause withClause(String search) {
+    return _node(search, (n) => n is WithClause);
+  }
+
+  YieldStatement yieldStatement(String search) {
+    return _node(search, (n) => n is YieldStatement);
+  }
+
   T _node<T>(String search, bool Function(AstNode) predicate) {
     int offset = this.offset(search);
 
@@ -421,7 +562,7 @@
     var result = node.thisOrAncestorMatching(predicate);
     if (result == null) {
       throw StateError(
-          'The node for |$search| had no matching ancestor in:\n$content');
+          'The node for |$search| had no matching ancestor in:\n$content\n$unit');
     }
     return result as T;
   }
diff --git a/pkg/analyzer/lib/src/test_utilities/mock_sdk.dart b/pkg/analyzer/lib/src/test_utilities/mock_sdk.dart
index 7693ddd..44a6369 100644
--- a/pkg/analyzer/lib/src/test_utilities/mock_sdk.dart
+++ b/pkg/analyzer/lib/src/test_utilities/mock_sdk.dart
@@ -7,13 +7,9 @@
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer/src/dart/analysis/experiments.dart';
-import 'package:analyzer/src/dart/sdk/sdk.dart';
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:meta/meta.dart';
 
-@Deprecated('Use createMockSdk() instead')
-const String sdkRoot = '/sdk';
-
 final MockSdkLibrary _LIB_ASYNC = MockSdkLibrary('async', [
   MockSdkLibraryUnit(
     'async/async.dart',
@@ -1142,8 +1138,9 @@
       throw 0;
 }
 
-enum ProcessStartMode {
-  normal,
+class ProcessStartMode {
+  static const normal = const ProcessStartMode._internal(0);
+  const ProcessStartMode._internal(int mode);
 }
 
 abstract class Process {
@@ -1192,7 +1189,6 @@
     bool errorsAreFatal = true,
     bool? checked,
     Map<String, String>? environment,
-    @deprecated Uri? packageRoot,
     Uri? packageConfig,
     bool automaticPackageResolution = false,
     String? debugName,
@@ -1303,51 +1299,6 @@
       );
 }
 
-@Deprecated('Use createMockSdk() and FolderBasedDartSdk instead.')
-class MockSdk extends FolderBasedDartSdk {
-  /// Optional [additionalLibraries] should have unique URIs, and paths in
-  /// their units are relative (will be put into `sdkRoot/lib`).
-  factory MockSdk({
-    required MemoryResourceProvider resourceProvider,
-    List<MockSdkLibrary> additionalLibraries = const [],
-  }) {
-    var sdkDirectory = resourceProvider.getFolder(
-      resourceProvider.convertPath(sdkRoot),
-    );
-    createMockSdk(
-      resourceProvider: resourceProvider,
-      root: sdkDirectory,
-      additionalLibraries: additionalLibraries,
-    );
-    return MockSdk._(resourceProvider, sdkDirectory);
-  }
-
-  /// Initialize a newly created SDK to represent the Dart SDK installed in the
-  /// [sdkDirectory].
-  MockSdk._(ResourceProvider resourceProvider, Folder sdkDirectory)
-      : super(resourceProvider, sdkDirectory);
-
-  @override
-  MemoryResourceProvider get resourceProvider {
-    return super.resourceProvider as MemoryResourceProvider;
-  }
-
-  @override
-  List<SdkLibraryImpl> get sdkLibraries {
-    return super.sdkLibraries.map((library) {
-      var pathContext = resourceProvider.pathContext;
-      var path = library.path;
-      if (pathContext.isAbsolute(path)) {
-        return library;
-      }
-      return SdkLibraryImpl(library.shortName)
-        ..path = pathContext.join(directory.path, 'lib', path)
-        ..category = library.category
-        ..documented = library.isDocumented;
-    }).toList();
-  }
-}
-
 class MockSdkLibrary implements SdkLibrary {
   final String name;
   final String categories;
diff --git a/pkg/analyzer/lib/src/util/uri.dart b/pkg/analyzer/lib/src/util/uri.dart
index 08e3008..4d60895 100644
--- a/pkg/analyzer/lib/src/util/uri.dart
+++ b/pkg/analyzer/lib/src/util/uri.dart
@@ -13,23 +13,10 @@
   return path;
 }
 
-/// If the [absoluteUri] is a `file` URI that has corresponding `package` URI,
-/// return it. If the URI is not valid, e.g. has empty path segments, so
-/// does not represent a valid file path, return `null`.
-Uri? rewriteFileToPackageUri(SourceFactory sourceFactory, Uri absoluteUri) {
-  // Only file URIs get rewritten into package URIs.
-  if (!absoluteUri.isScheme('file')) {
-    return absoluteUri;
-  }
-
-  // It must be a valid URI, e.g. `file:///home/` is not.
-  var pathSegments = absoluteUri.pathSegments;
-  if (pathSegments.isEmpty || pathSegments.last.isEmpty) {
-    return null;
-  }
-
-  // We ask for Source only because `restoreUri` needs it.
-  // TODO(scheglov) Add more direct way to convert a path to URI.
+/// Return the canonical URI for the given [absoluteUri], for example a `file`
+/// URI to the corresponding `package` URI. If the URI is not valid, so does
+/// not represent a valid file path, return `null`.
+Uri? rewriteToCanonicalUri(SourceFactory sourceFactory, Uri absoluteUri) {
   var source = sourceFactory.forUri2(absoluteUri);
   if (source == null) {
     return null;
diff --git a/pkg/analyzer/lib/src/util/yaml.dart b/pkg/analyzer/lib/src/util/yaml.dart
index dfa104e..416828c 100644
--- a/pkg/analyzer/lib/src/util/yaml.dart
+++ b/pkg/analyzer/lib/src/util/yaml.dart
@@ -106,12 +106,15 @@
 }
 
 extension YamlMapExtensions on YamlMap {
-  /// Return the value associated with the key whose value matches the given
-  /// [key], or `null` if there is no matching key.
-  YamlNode? valueAt(String key) {
-    for (var keyNode in nodes.keys) {
-      if (keyNode is YamlScalar && keyNode.value == key) {
-        return nodes[keyNode];
+  /// Return [nodes] as a Map with [YamlNode] keys.
+  Map<YamlNode, YamlNode> get nodeMap => nodes.cast<YamlNode, YamlNode>();
+
+  /// Return the [YamlNode] associated with the given [key], or `null` if there
+  /// is no matching key.
+  YamlNode? getKey(String key) {
+    for (YamlNode k in nodes.keys) {
+      if (k is YamlScalar && k.value == key) {
+        return k;
       }
     }
     return null;
@@ -128,17 +131,14 @@
     return null;
   }
 
-  /// Return the [YamlNode] associated with the given [key], or `null` if there
-  /// is no matching key.
-  YamlNode? getKey(String key) {
-    for (YamlNode k in nodes.keys) {
-      if (k is YamlScalar && k.value == key) {
-        return k;
+  /// Return the value associated with the key whose value matches the given
+  /// [key], or `null` if there is no matching key.
+  YamlNode? valueAt(String key) {
+    for (var keyNode in nodes.keys) {
+      if (keyNode is YamlScalar && keyNode.value == key) {
+        return nodes[keyNode];
       }
     }
     return null;
   }
-
-  /// Return [nodes] as a Map with [YamlNode] keys.
-  Map<YamlNode, YamlNode> get nodeMap => nodes.cast<YamlNode, YamlNode>();
 }
diff --git a/pkg/analyzer/lib/src/workspace/bazel.dart b/pkg/analyzer/lib/src/workspace/bazel.dart
index e8f24d5..5198c44 100644
--- a/pkg/analyzer/lib/src/workspace/bazel.dart
+++ b/pkg/analyzer/lib/src/workspace/bazel.dart
@@ -242,7 +242,7 @@
     resolvers.add(packageUriResolver);
     resolvers.add(BazelFileUriResolver(this));
     if (summaryData != null) {
-      resolvers.add(InSummaryUriResolver(provider, summaryData));
+      resolvers.add(InSummaryUriResolver(summaryData));
     }
     return SourceFactory(resolvers);
   }
diff --git a/pkg/analyzer/messages.yaml b/pkg/analyzer/messages.yaml
index 7ad997e..b079038 100644
--- a/pkg/analyzer/messages.yaml
+++ b/pkg/analyzer/messages.yaml
@@ -1082,7 +1082,7 @@
       immediately enclosing _a_ is not declared asynchronous. (Where _a_ is the
       await expression.)
   BODY_MIGHT_COMPLETE_NORMALLY:
-    problemMessage: "The body might complete normally, causing 'null' to be returned, but the return type is a potentially non-nullable type."
+    problemMessage: "The body might complete normally, causing 'null' to be returned, but the return type, '{0}', is a potentially non-nullable type."
     correctionMessage: Try adding either a return or a throw statement at the end.
     hasPublishedDocs: true
     comment: No parameters.
@@ -1146,13 +1146,15 @@
       }
       ```
 
-      If the method intentionally returns `null` at the end, then change the
+      If the method intentionally returns `null` at the end, then add an
+      explicit return of `null` at the end of the method and change the
       return type so that it's valid to return `null`:
 
       ```dart
       class C<T> {
         T? m(T t) {
           print(t);
+          return null;
         }
       }
       ```
@@ -13775,6 +13777,10 @@
       }
       ```
 FfiCode:
+  ABI_SPECIFIC_INTEGER_INVALID:
+    problemMessage: "Classes extending 'AbiSpecificInteger' must have exactly one const constructor, no other members, and no type arguments."
+    correctionMessage: Try removing all type arguments, removing all members, and adding one const constructor.
+    comment: No parameters.
   ABI_SPECIFIC_INTEGER_MAPPING_EXTRA:
     problemMessage: "Classes extending 'AbiSpecificInteger' must have exactly one 'AbiSpecificIntegerMapping' annotation specifying the mapping from ABI to a 'NativeType' integer with a fixed size."
     correctionMessage: Try removing the extra annotation.
@@ -13978,24 +13984,24 @@
       1: the name of the class being extended, implemented, or mixed in
   SUBTYPE_OF_STRUCT_CLASS_IN_EXTENDS:
     sharedName: SUBTYPE_OF_STRUCT_CLASS
-    problemMessage: "The class '{0}' can't extend '{1}' because '{1}' is a subtype of 'Struct' or 'Union'."
-    correctionMessage: "Try extending 'Struct' or 'Union' directly."
+    problemMessage: "The class '{0}' can't extend '{1}' because '{1}' is a subtype of 'Struct', 'Union', or 'AbiSpecificInteger'."
+    correctionMessage: "Try extending 'Struct', 'Union', or 'AbiSpecificInteger' directly."
     comment: |-
       Parameters:
       0: the name of the subclass
       1: the name of the class being extended, implemented, or mixed in
   SUBTYPE_OF_STRUCT_CLASS_IN_IMPLEMENTS:
     sharedName: SUBTYPE_OF_STRUCT_CLASS
-    problemMessage: "The class '{0}' can't implement '{1}' because '{1}' is a subtype of 'Struct' or 'Union'."
-    correctionMessage: "Try extending 'Struct' or 'Union' directly."
+    problemMessage: "The class '{0}' can't implement '{1}' because '{1}' is a subtype of 'Struct', 'Union', or 'AbiSpecificInteger'."
+    correctionMessage: "Try extending 'Struct', 'Union', or 'AbiSpecificInteger' directly."
     comment: |-
       Parameters:
       0: the name of the subclass
       1: the name of the class being extended, implemented, or mixed in
   SUBTYPE_OF_STRUCT_CLASS_IN_WITH:
     sharedName: SUBTYPE_OF_STRUCT_CLASS
-    problemMessage: "The class '{0}' can't mix in '{1}' because '{1}' is a subtype of 'Struct' or 'Union'."
-    correctionMessage: "Try extending 'Struct' or 'Union' directly."
+    problemMessage: "The class '{0}' can't mix in '{1}' because '{1}' is a subtype of 'Struct', 'Union', or 'AbiSpecificInteger'."
+    correctionMessage: "Try extending 'Struct', 'Union', or 'AbiSpecificInteger' directly."
     comment: |-
       Parameters:
       0: the name of the subclass
@@ -14065,6 +14071,13 @@
     problemMessage: "'{0}' is marked 'doNotStore' and shouldn't be assigned to a field or top-level variable."
     correctionMessage: Try removing the assignment.
     comment: Users should not assign values marked `@doNotStore`.
+  BODY_MIGHT_COMPLETE_NORMALLY_NULLABLE:
+    problemMessage: "This function has a nullable return type of '{0}', but ends without returning a value."
+    correctionMessage: "Try adding a return statement, or if no value is ever returned, try changing the return type to 'void'."
+    hasPublishedDocs: false
+    comment: |-
+      Parameters:
+      0: the name of the declared return type
   CAN_BE_NULL_AFTER_NULL_AWARE:
     problemMessage: "The receiver uses '?.', so its value can be null."
     correctionMessage: "Replace the '.' with a '?.' in the invocation."
diff --git a/pkg/analyzer/pubspec.yaml b/pkg/analyzer/pubspec.yaml
index 14a27f7..e706822 100644
--- a/pkg/analyzer/pubspec.yaml
+++ b/pkg/analyzer/pubspec.yaml
@@ -1,5 +1,5 @@
 name: analyzer
-version: 2.8.0
+version: 3.1.0-dev
 description: This package provides a library that performs static analysis of Dart code.
 homepage: https://github.com/dart-lang/sdk/tree/main/pkg/analyzer
 
@@ -7,7 +7,7 @@
   sdk: '>=2.14.0 <3.0.0'
 
 dependencies:
-  _fe_analyzer_shared: ^31.0.0
+  _fe_analyzer_shared: ^32.0.0
   cli_util: ^0.3.0
   collection: ^1.15.0
   convert: ^3.0.0
diff --git a/pkg/analyzer/test/dart/ast/ast_test.dart b/pkg/analyzer/test/dart/ast/ast_test.dart
index 12d892c..5519a0d 100644
--- a/pkg/analyzer/test/dart/ast/ast_test.dart
+++ b/pkg/analyzer/test/dart/ast/ast_test.dart
@@ -56,8 +56,9 @@
         "b",
         AstTestFactory.formalParameterList(),
         initializers);
-    ClassDeclaration clazz = AstTestFactory.classDeclaration(null, "Test", null,
-        null, null, null, [defaultConstructor, aConstructor, bConstructor]);
+    ClassDeclaration clazz = AstTestFactory.classDeclaration(
+        null, "Test", null, null, null, null,
+        members: [defaultConstructor, aConstructor, bConstructor]);
     expect(clazz.getConstructor(null), same(defaultConstructor));
     expect(clazz.getConstructor("a"), same(aConstructor));
     expect(clazz.getConstructor("b"), same(bConstructor));
@@ -68,11 +69,12 @@
     VariableDeclaration aVar = AstTestFactory.variableDeclaration("a");
     VariableDeclaration bVar = AstTestFactory.variableDeclaration("b");
     VariableDeclaration cVar = AstTestFactory.variableDeclaration("c");
-    ClassDeclaration clazz =
-        AstTestFactory.classDeclaration(null, "Test", null, null, null, null, [
-      AstTestFactory.fieldDeclaration2(false, null, [aVar]),
-      AstTestFactory.fieldDeclaration2(false, null, [bVar, cVar])
-    ]);
+    ClassDeclaration clazz = AstTestFactory.classDeclaration(
+        null, "Test", null, null, null, null,
+        members: [
+          AstTestFactory.fieldDeclaration2(false, null, [aVar]),
+          AstTestFactory.fieldDeclaration2(false, null, [bVar, cVar])
+        ]);
     expect(clazz.getField("a"), same(aVar));
     expect(clazz.getField("b"), same(bVar));
     expect(clazz.getField("c"), same(cVar));
@@ -95,7 +97,8 @@
         AstTestFactory.identifier3("b"),
         AstTestFactory.formalParameterList());
     ClassDeclaration clazz = AstTestFactory.classDeclaration(
-        null, "Test", null, null, null, null, [aMethod, bMethod]);
+        null, "Test", null, null, null, null,
+        members: [aMethod, bMethod]);
     expect(clazz.getMethod("a"), same(aMethod));
     expect(clazz.getMethod("b"), same(bMethod));
     expect(clazz.getMethod("noSuchMethod"), isNull);
diff --git a/pkg/analyzer/test/file_system/file_system_test_support.dart b/pkg/analyzer/test/file_system/file_system_test_support.dart
index 0550aa1..11cf39f 100644
--- a/pkg/analyzer/test/file_system/file_system_test_support.dart
+++ b/pkg/analyzer/test/file_system/file_system_test_support.dart
@@ -229,15 +229,6 @@
     expect(() => file.modificationStamp, throwsA(isFileSystemException));
   }
 
-  @deprecated
-  test_parent() {
-    File file = getFile(exists: true);
-
-    var parent = file.parent!;
-    expect(parent.exists, isTrue);
-    expect(parent.path, defaultFolderPath);
-  }
-
   test_parent2() {
     File file = getFile(exists: true);
 
@@ -925,22 +916,6 @@
     expect(folder.exists, isFalse);
   }
 
-  @Deprecated('Not used by clients')
-  test_getModificationTimes_existing() async {
-    Source source = getFile(exists: true).createSource();
-
-    var times = await provider.getModificationTimes([source]);
-    expect(times, [source.modificationStamp]);
-  }
-
-  @Deprecated('Not used by clients')
-  test_getModificationTimes_notExisting() async {
-    Source source = getFile(exists: false).createSource();
-
-    var times = await provider.getModificationTimes([source]);
-    expect(times, [-1]);
-  }
-
   test_getResource_file_existing() {
     String filePath = getFile(exists: true).path;
 
diff --git a/pkg/analyzer/test/file_system/overlay_file_system_test.dart b/pkg/analyzer/test/file_system/overlay_file_system_test.dart
index fd9a6df..dae3df2 100644
--- a/pkg/analyzer/test/file_system/overlay_file_system_test.dart
+++ b/pkg/analyzer/test/file_system/overlay_file_system_test.dart
@@ -812,20 +812,6 @@
     expect(folder.exists, isTrue);
   }
 
-  @Deprecated('Not used by clients')
-  test_getModificationTimes_withoutOverlay() async {
-    Source source = _file(exists: true).createSource();
-    List<int> times = await provider.getModificationTimes([source]);
-    expect(times, [source.modificationStamp]);
-  }
-
-  @Deprecated('Not used by clients')
-  test_getModificationTimes_withOverlay() async {
-    Source source = _file(exists: true, withOverlay: true).createSource();
-    List<int> times = await provider.getModificationTimes([source]);
-    expect(times, [42]);
-  }
-
   test_getResource_file_existing_withoutOverlay() {
     String path = _file(exists: true).path;
     Resource resource = provider.getResource(path);
diff --git a/pkg/analyzer/test/generated/element_resolver_test.dart b/pkg/analyzer/test/generated/element_resolver_test.dart
index a018a3e..f6b0fed 100644
--- a/pkg/analyzer/test/generated/element_resolver_test.dart
+++ b/pkg/analyzer/test/generated/element_resolver_test.dart
@@ -2,33 +2,14 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'package:analyzer/dart/analysis/features.dart';
 import 'package:analyzer/dart/ast/ast.dart';
-import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element.dart';
-import 'package:analyzer/dart/element/scope.dart';
-import 'package:analyzer/dart/element/type.dart';
-import 'package:analyzer/dart/element/type_provider.dart';
-import 'package:analyzer/src/dart/ast/ast.dart';
-import 'package:analyzer/src/dart/ast/ast_factory.dart';
-import 'package:analyzer/src/dart/element/element.dart';
-import 'package:analyzer/src/dart/element/inheritance_manager3.dart';
-import 'package:analyzer/src/dart/resolver/flow_analysis_visitor.dart';
-import 'package:analyzer/src/generated/element_resolver.dart';
-import 'package:analyzer/src/generated/resolver.dart';
-import 'package:analyzer/src/generated/source.dart';
-import 'package:analyzer/src/generated/testing/ast_test_factory.dart';
-import 'package:analyzer/src/generated/testing/element_factory.dart';
-import 'package:analyzer/src/source/source_resource.dart';
-import 'package:analyzer/src/test_utilities/resource_provider_mixin.dart';
+import 'package:analyzer/src/dart/error/hint_codes.dart';
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
 import '../src/dart/resolution/context_collection_resolution.dart';
 import '../util/element_type_matchers.dart';
-import 'elements_types_mixin.dart';
-import 'test_analysis_context.dart';
-import 'test_support.dart';
 
 main() {
   defineReflectiveSuite(() {
@@ -37,15 +18,6 @@
   });
 }
 
-/// Wrapper around the test package's `fail` function.
-///
-/// Unlike the test package's `fail` function, this function is not annotated
-/// with @alwaysThrows, so we can call it at the top of a test method without
-/// causing the rest of the method to be flagged as dead code.
-void _fail(String message) {
-  fail(message);
-}
-
 @reflectiveTest
 class AnnotationElementResolverTest extends PubPackageResolutionTest {
   test_class_namedConstructor() async {
@@ -265,545 +237,332 @@
 }
 
 @reflectiveTest
-class ElementResolverTest with ResourceProviderMixin, ElementsTypesMixin {
-  /// The error listener to which errors will be reported.
-  late GatheringErrorListener _listener;
-
-  /// The type provider used to access the types.
-  late TypeProvider _typeProvider;
-
-  /// The library containing the code being resolved.
-  late LibraryElementImpl _definingLibrary;
-
-  /// The resolver visitor that maintains the state for the resolver.
-  late ResolverVisitor _visitor;
-
-  /// The resolver being used to resolve the test cases.
-  late ElementResolver _resolver;
-
-  @override
-  TypeProvider get typeProvider => _typeProvider;
-
-  void fail_visitExportDirective_combinators() {
-    _fail("Not yet tested");
-    // Need to set up the exported library so that the identifier can be
-    // resolved.
-    ExportDirective directive = AstTestFactory.exportDirective2('dart:math', [
-      AstTestFactory.hideCombinator2(["A"])
-    ]);
-    _resolveNode(directive);
-    _listener.assertNoErrors();
-  }
-
-  void fail_visitFunctionExpressionInvocation() {
-    _fail("Not yet tested");
-    _listener.assertNoErrors();
-  }
-
-  void fail_visitImportDirective_combinators_noPrefix() {
-    _fail("Not yet tested");
-    // Need to set up the imported library so that the identifier can be
-    // resolved.
-    ImportDirective directive =
-        AstTestFactory.importDirective3('dart:math', null, [
-      AstTestFactory.showCombinator2(["A"])
-    ]);
-    _resolveNode(directive);
-    _listener.assertNoErrors();
-  }
-
-  void fail_visitImportDirective_combinators_prefix() {
-    _fail("Not yet tested");
-    // Need to set up the imported library so that the identifiers can be
-    // resolved.
-    String prefixName = "p";
-    _definingLibrary.imports = <ImportElement>[
-      ElementFactory.importFor(
-          _LibraryElementMock(), ElementFactory.prefix(prefixName))
-    ];
-    ImportDirective directive =
-        AstTestFactory.importDirective3('dart:math', prefixName, [
-      AstTestFactory.showCombinator2(["A"]),
-      AstTestFactory.hideCombinator2(["B"])
-    ]);
-    _resolveNode(directive);
-    _listener.assertNoErrors();
-  }
-
-  void fail_visitRedirectingConstructorInvocation() {
-    _fail("Not yet tested");
-    _listener.assertNoErrors();
-  }
-
-  void setUp() {
-    _listener = GatheringErrorListener();
-    _createResolver();
-  }
-
-  @FailingTest(issue: 'https://github.com/dart-lang/sdk/issues/44522')
+class ElementResolverTest extends PubPackageResolutionTest {
   test_visitBreakStatement_withLabel() async {
-    // loop: while (true) {
-    //   break loop;
-    // }
-    String label = "loop";
-    LabelElementImpl labelElement = LabelElementImpl(label, -1, false, false);
-    BreakStatement breakStatement = AstTestFactory.breakStatement2(label);
-    Expression condition = AstTestFactory.booleanLiteral(true);
-    WhileStatement whileStatement =
-        AstTestFactory.whileStatement(condition, breakStatement);
-    expect(_resolveBreak(breakStatement, labelElement, whileStatement),
-        same(labelElement));
-    expect(breakStatement.target, same(whileStatement));
-    _listener.assertNoErrors();
+    await assertNoErrorsInCode('''
+test() {
+  loop: while (true) {
+    break loop;
+  }
+}
+''');
+    var breakStatement = findNode.breakStatement('break loop');
+    expect(breakStatement.label!.staticElement, findElement.label('loop'));
+    expect(breakStatement.target, findNode.whileStatement('while (true)'));
   }
 
   test_visitBreakStatement_withoutLabel() async {
-    BreakStatement statement = AstTestFactory.breakStatement();
-    _resolveStatement(statement, null, null);
-    _listener.assertNoErrors();
+    await assertNoErrorsInCode('''
+test() {
+  while (true) {
+    break;
+  }
+}
+''');
+    var breakStatement = findNode.breakStatement('break');
+    expect(breakStatement.target, findNode.whileStatement('while (true)'));
   }
 
   test_visitCommentReference_prefixedIdentifier_class_getter() async {
-    LibraryElementImpl library =
-        ElementFactory.library(_definingLibrary.context, "lib");
-    CompilationUnitElementImpl unit =
-        library.definingCompilationUnit as CompilationUnitElementImpl;
-    ClassElementImpl classA = ElementFactory.classElement2("A");
-    unit.classes = [classA];
+    await assertNoErrorsInCode('''
+class A {
+  int get p => 0;
+  set p(int value) {}
+}
 
-    // set accessors
-    String propName = "p";
-    PropertyAccessorElement getter =
-        ElementFactory.getterElement(propName, false, _typeProvider.intType);
-    PropertyAccessorElement setter =
-        ElementFactory.setterElement(propName, false, _typeProvider.intType);
-    classA.accessors = <PropertyAccessorElement>[getter, setter];
-    // prepare "A.p"
-    PrefixedIdentifierImpl prefixed = AstTestFactory.identifier5('A', 'p');
-    prefixed.prefix.scopeLookupResult = ScopeLookupResult(classA, null);
-    CommentReference commentReference =
-        astFactory.commentReference(null, prefixed);
-    // resolve
-    _resolveNode(commentReference);
-    expect(prefixed.prefix.staticElement, classA);
-    expect(prefixed.identifier.staticElement, getter);
-    _listener.assertNoErrors();
+/// [A.p]
+test() {}
+''');
+    var prefixed = findNode.prefixed('A.p');
+    expect(prefixed.prefix.staticElement, findElement.class_('A'));
+    expect(prefixed.identifier.staticElement, findElement.getter('p'));
   }
 
   test_visitCommentReference_prefixedIdentifier_class_method() async {
-    LibraryElementImpl library =
-        ElementFactory.library(_definingLibrary.context, "lib");
-    CompilationUnitElementImpl unit =
-        library.definingCompilationUnit as CompilationUnitElementImpl;
-    ClassElementImpl classA = ElementFactory.classElement2("A");
-    unit.classes = [classA];
-    // set method
-    MethodElement method =
-        ElementFactory.methodElement("m", _typeProvider.intType);
-    classA.methods = <MethodElement>[method];
-    // prepare "A.m"
-    PrefixedIdentifierImpl prefixed = AstTestFactory.identifier5('A', 'm');
-    prefixed.prefix.scopeLookupResult = ScopeLookupResult(classA, null);
-    CommentReference commentReference =
-        astFactory.commentReference(null, prefixed);
-    // resolve
-    _resolveNode(commentReference);
-    expect(prefixed.prefix.staticElement, classA);
-    expect(prefixed.identifier.staticElement, method);
-    _listener.assertNoErrors();
+    await assertNoErrorsInCode('''
+class A {
+  m() {}
+}
+
+/// [A.m]
+test() {}
+''');
+    var prefixed = findNode.prefixed('A.m');
+    expect(prefixed.prefix.staticElement, findElement.class_('A'));
+    expect(prefixed.identifier.staticElement, findElement.method('m'));
   }
 
   test_visitCommentReference_prefixedIdentifier_class_operator() async {
-    LibraryElementImpl library =
-        ElementFactory.library(_definingLibrary.context, "lib");
-    CompilationUnitElementImpl unit =
-        library.definingCompilationUnit as CompilationUnitElementImpl;
-    ClassElementImpl classA = ElementFactory.classElement2("A");
-    unit.classes = [classA];
-    // set method
-    MethodElement method =
-        ElementFactory.methodElement("==", _typeProvider.boolType);
-    classA.methods = <MethodElement>[method];
-    // prepare "A.=="
-    PrefixedIdentifierImpl prefixed = AstTestFactory.identifier5('A', '==');
-    prefixed.prefix.scopeLookupResult = ScopeLookupResult(classA, null);
-    CommentReference commentReference =
-        astFactory.commentReference(null, prefixed);
-    // resolve
-    _resolveNode(commentReference);
-    expect(prefixed.prefix.staticElement, classA);
-    expect(prefixed.identifier.staticElement, method);
-    _listener.assertNoErrors();
+    await assertNoErrorsInCode('''
+class A {
+  operator ==(other) => true;
+}
+
+/// [A.==]
+test() {}
+''');
+    var prefixed = findNode.prefixed('A.==');
+    expect(prefixed.prefix.staticElement, findElement.class_('A'));
+    expect(prefixed.identifier.staticElement, findElement.method('=='));
   }
 
   test_visitConstructorName_named() async {
-    ClassElementImpl classA = ElementFactory.classElement2("A");
-    _encloseElement(classA);
-    String constructorName = "a";
-    ConstructorElement constructor =
-        ElementFactory.constructorElement2(classA, constructorName);
-    classA.constructors = <ConstructorElement>[constructor];
-    ConstructorName name = AstTestFactory.constructorName(
-        AstTestFactory.namedType(classA), constructorName);
-    _resolveNode(name);
-    expect(name.staticElement, same(constructor));
-    _listener.assertNoErrors();
+    await assertNoErrorsInCode('''
+class A implements B {
+  A.a();
+}
+class B {
+  factory B() = A.a/*reference*/;
+}
+''');
+    expect(findNode.constructorName('A.a/*reference*/').staticElement,
+        same(findElement.constructor('a')));
   }
 
   test_visitConstructorName_unnamed() async {
-    ClassElementImpl classA = ElementFactory.classElement2("A");
-    _encloseElement(classA);
-    String constructorName = 'named';
-    ConstructorElement constructor =
-        ElementFactory.constructorElement2(classA, constructorName);
-    classA.constructors = <ConstructorElement>[constructor];
-    ConstructorName name = AstTestFactory.constructorName(
-        AstTestFactory.namedType(classA), constructorName);
-    _resolveNode(name);
-    expect(name.staticElement, same(constructor));
-    _listener.assertNoErrors();
+    await assertNoErrorsInCode('''
+class A implements B {
+  A();
+}
+class B {
+  factory B() = A/*reference*/;
+}
+''');
+    expect(findNode.constructorName('A/*reference*/').staticElement,
+        same(findElement.unnamedConstructor('A')));
   }
 
-  @FailingTest(issue: 'https://github.com/dart-lang/sdk/issues/44522')
   test_visitContinueStatement_withLabel() async {
-    // loop: while (true) {
-    //   continue loop;
-    // }
-    String label = "loop";
-    LabelElementImpl labelElement = LabelElementImpl(label, -1, false, false);
-    ContinueStatement continueStatement =
-        AstTestFactory.continueStatement(label);
-    Expression condition = AstTestFactory.booleanLiteral(true);
-    WhileStatement whileStatement =
-        AstTestFactory.whileStatement(condition, continueStatement);
-    expect(_resolveContinue(continueStatement, labelElement, whileStatement),
-        same(labelElement));
-    expect(continueStatement.target, same(whileStatement));
-    _listener.assertNoErrors();
+    await assertNoErrorsInCode('''
+test() {
+  loop: while (true) {
+    continue loop;
+  }
+}
+''');
+    var continueStatement = findNode.continueStatement('continue loop');
+    expect(continueStatement.label!.staticElement, findElement.label('loop'));
+    expect(continueStatement.target, findNode.whileStatement('while (true)'));
   }
 
   test_visitContinueStatement_withoutLabel() async {
-    ContinueStatement statement = AstTestFactory.continueStatement();
-    _resolveStatement(statement, null, null);
-    _listener.assertNoErrors();
+    await assertNoErrorsInCode('''
+test() {
+  while (true) {
+    continue;
+  }
+}
+''');
+    var continueStatement = findNode.continueStatement('continue');
+    expect(continueStatement.target, findNode.whileStatement('while (true)'));
   }
 
-  @FailingTest(issue: 'https://github.com/dart-lang/sdk/issues/44522')
+  test_visitExportDirective_combinators() async {
+    await assertNoErrorsInCode('''
+export 'dart:math' hide pi;
+''');
+    var pi = findElement
+        .export('dart:math')
+        .exportedLibrary!
+        .exportNamespace
+        .get('pi') as PropertyAccessorElement;
+    expect(findNode.simple('pi').staticElement, pi.variable);
+  }
+
   test_visitExportDirective_noCombinators() async {
-    var directive = AstTestFactory.exportDirective2('dart:math');
-    directive.element = ElementFactory.exportFor(
-        ElementFactory.library(_definingLibrary.context, "lib"));
-    _resolveNode(directive);
-    _listener.assertNoErrors();
+    await assertNoErrorsInCode('''
+export 'dart:math';
+''');
+    expect(findNode.export('dart:math').element!.exportedLibrary!.name,
+        'dart.math');
   }
 
   test_visitFieldFormalParameter() async {
-    String fieldName = "f";
-    InterfaceType intType = _typeProvider.intType;
-    FieldElementImpl fieldElement =
-        ElementFactory.fieldElement(fieldName, false, false, false, intType);
-    ClassElementImpl classA = ElementFactory.classElement2("A");
-    classA.fields = <FieldElement>[fieldElement];
-    var parameter = AstTestFactory.fieldFormalParameter2(fieldName);
-    FieldFormalParameterElementImpl parameterElement =
-        ElementFactory.fieldFormalParameter(parameter.identifier);
-    parameterElement.field = fieldElement;
-    parameterElement.type = intType;
-    parameter.identifier.staticElement = parameterElement;
-    _resolveInClass(parameter, classA);
-    expect(parameter.declaredElement!.type, same(intType));
+    await assertNoErrorsInCode('''
+class A {
+  int f;
+  A(this.f);
+}
+''');
+    expect(
+        findNode.fieldFormalParameter('this.f').declaredElement!.type, intType);
   }
 
-  @FailingTest(issue: 'https://github.com/dart-lang/sdk/issues/44522')
+  test_visitImportDirective_combinators_noPrefix() async {
+    await assertErrorsInCode('''
+import 'dart:math' show pi;
+''', [
+      error(HintCode.UNUSED_IMPORT, 7, 11),
+    ]);
+    var pi = findElement
+        .import('dart:math')
+        .importedLibrary!
+        .exportNamespace
+        .get('pi') as PropertyAccessorElement;
+    expect(findNode.simple('pi').staticElement, pi.variable);
+  }
+
+  test_visitImportDirective_combinators_prefix() async {
+    await assertErrorsInCode('''
+import 'dart:math' as p show pi hide ln10;
+''', [
+      error(HintCode.UNUSED_IMPORT, 7, 11),
+    ]);
+    var mathNamespace =
+        findElement.import('dart:math').importedLibrary!.exportNamespace;
+    var pi = mathNamespace.get('pi') as PropertyAccessorElement;
+    expect(findNode.simple('pi').staticElement, pi.variable);
+    var ln10 = mathNamespace.get('ln10') as PropertyAccessorElement;
+    expect(findNode.simple('ln10').staticElement, ln10.variable);
+  }
+
   test_visitImportDirective_noCombinators_noPrefix() async {
-    var directive = AstTestFactory.importDirective3('dart:math', null);
-    directive.element = ElementFactory.importFor(
-        ElementFactory.library(_definingLibrary.context, "lib"), null);
-    _resolveNode(directive);
-    _listener.assertNoErrors();
+    await assertErrorsInCode('''
+import 'dart:math';
+''', [
+      error(HintCode.UNUSED_IMPORT, 7, 11),
+    ]);
+    expect(findNode.import('dart:math').element!.importedLibrary!.name,
+        'dart.math');
   }
 
-  @FailingTest(issue: 'https://github.com/dart-lang/sdk/issues/44522')
   test_visitImportDirective_noCombinators_prefix() async {
-    String prefixName = "p";
-    ImportElement importElement = ElementFactory.importFor(
-        ElementFactory.library(_definingLibrary.context, "lib"),
-        ElementFactory.prefix(prefixName));
-    _definingLibrary.imports = <ImportElement>[importElement];
-    var directive = AstTestFactory.importDirective3('dart:math', prefixName);
-    directive.element = importElement;
-    _resolveNode(directive);
-    _listener.assertNoErrors();
+    await assertErrorsInCode('''
+import 'dart:math' as p;
+''', [
+      error(HintCode.UNUSED_IMPORT, 7, 11),
+    ]);
+    expect(findNode.import('dart:math').element!.importedLibrary!.name,
+        'dart.math');
   }
 
-  @FailingTest(issue: 'https://github.com/dart-lang/sdk/issues/44522')
   test_visitImportDirective_withCombinators() async {
-    ShowCombinator combinator = AstTestFactory.showCombinator2(["A", "B", "C"]);
-    var directive =
-        AstTestFactory.importDirective3('dart:math', null, [combinator]);
-    LibraryElementImpl library =
-        ElementFactory.library(_definingLibrary.context, "lib");
-    TopLevelVariableElementImpl varA =
-        ElementFactory.topLevelVariableElement2("A");
-    TopLevelVariableElementImpl varB =
-        ElementFactory.topLevelVariableElement2("B");
-    TopLevelVariableElementImpl varC =
-        ElementFactory.topLevelVariableElement2("C");
-    CompilationUnitElementImpl unit =
-        library.definingCompilationUnit as CompilationUnitElementImpl;
-    unit.accessors = <PropertyAccessorElement>[
-      varA.getter!,
-      varA.setter!,
-      varB.getter!,
-      varC.setter!
-    ];
-    unit.topLevelVariables = <TopLevelVariableElement>[varA, varB, varC];
-    directive.element = ElementFactory.importFor(library, null);
-    _resolveNode(directive);
-    expect(combinator.shownNames[0].staticElement, same(varA));
-    expect(combinator.shownNames[1].staticElement, same(varB));
-    expect(combinator.shownNames[2].staticElement, same(varC));
-    _listener.assertNoErrors();
+    newFile('$testPackageLibPath/lib1.dart', content: r'''
+int v1 = 0;
+final int v2 = 0;
+''');
+    await assertErrorsInCode('''
+import 'lib1.dart' show v1, v2;
+''', [
+      error(HintCode.UNUSED_IMPORT, 7, 11),
+    ]);
+    var importedVariables = findNode
+        .import('lib1.dart')
+        .element!
+        .importedLibrary!
+        .definingCompilationUnit
+        .topLevelVariables;
+    var v1 = importedVariables.where((v) => v.name == 'v1').single;
+    var v2 = importedVariables.where((v) => v.name == 'v2').single;
+    expect(findNode.simple('v1').staticElement, same(v1));
+    expect(findNode.simple('v2').staticElement, same(v2));
   }
 
   test_visitInstanceCreationExpression_named() async {
-    ClassElementImpl classA = ElementFactory.classElement2("A");
-    String constructorName = "a";
-    ConstructorElement constructor =
-        ElementFactory.constructorElement2(classA, constructorName);
-    classA.constructors = <ConstructorElement>[constructor];
-    var name = AstTestFactory.constructorName(
-        AstTestFactory.namedType(classA), constructorName);
-    name.staticElement = constructor;
-    InstanceCreationExpression creation =
-        AstTestFactory.instanceCreationExpression(Keyword.NEW, name);
-    _resolveNode(creation);
-    _listener.assertNoErrors();
+    await assertNoErrorsInCode('''
+class A {
+  A.a();
+}
+test() => new A.a();
+''');
+    expect(findNode.instanceCreation('new A.a').constructorName.staticElement,
+        findElement.constructor('a'));
+  }
+
+  test_visitInstanceCreationExpression_named_namedParameter() async {
+    await assertNoErrorsInCode('''
+class A {
+  A.named({int a = 0});
+}
+test() => new A.named(a: 0);
+''');
+    expect(
+        findNode.simple('a:').staticElement, same(findElement.parameter('a')));
   }
 
   test_visitInstanceCreationExpression_unnamed() async {
-    ClassElementImpl classA = ElementFactory.classElement2("A");
-    String constructorName = 'named';
-    ConstructorElement constructor =
-        ElementFactory.constructorElement2(classA, constructorName);
-    classA.constructors = <ConstructorElement>[constructor];
-    var name = AstTestFactory.constructorName(
-        AstTestFactory.namedType(classA), constructorName);
-    name.staticElement = constructor;
-    InstanceCreationExpression creation =
-        AstTestFactory.instanceCreationExpression(Keyword.NEW, name);
-    _resolveNode(creation);
-    _listener.assertNoErrors();
-  }
-
-  test_visitInstanceCreationExpression_unnamed_namedParameter() async {
-    ClassElementImpl classA = ElementFactory.classElement2("A");
-    String constructorName = 'named';
-    ConstructorElementImpl constructor =
-        ElementFactory.constructorElement2(classA, constructorName);
-    String parameterName = "a";
-    ParameterElement parameter =
-        ElementFactory.namedParameter2(parameterName, _typeProvider.intType);
-    constructor.parameters = <ParameterElement>[parameter];
-    classA.constructors = <ConstructorElement>[constructor];
-    var name = AstTestFactory.constructorName(
-        AstTestFactory.namedType(classA), constructorName);
-    name.staticElement = constructor;
-    InstanceCreationExpression creation =
-        AstTestFactory.instanceCreationExpression(Keyword.NEW, name, [
-      AstTestFactory.namedExpression2(parameterName, AstTestFactory.integer(0))
-    ]);
-    _resolveNode(creation);
-    expect(
-        (creation.argumentList.arguments[0] as NamedExpression)
-            .name
-            .label
-            .staticElement,
-        same(parameter));
-    _listener.assertNoErrors();
+    await assertNoErrorsInCode('''
+class A {}
+test() => new A();
+''');
+    expect(findNode.instanceCreation('new A').constructorName.staticElement,
+        findElement.unnamedConstructor('A'));
   }
 
   test_visitMethodInvocation() async {
-    InterfaceType numType = _typeProvider.numType;
-    var left = AstTestFactory.identifier3("i");
-    left.staticType = numType;
-    String methodName = "abs";
-    MethodInvocation invocation =
-        AstTestFactory.methodInvocation(left, methodName);
-    _resolveNode(invocation);
-    expect(invocation.methodName.staticElement!.declaration,
-        same(numType.getMethod(methodName)));
-    _listener.assertNoErrors();
+    await assertNoErrorsInCode('''
+num get i => 0;
+test() => i.abs();
+''');
+    expect(
+        findNode
+            .methodInvocation('i.abs()')
+            .methodName
+            .staticElement!
+            .declaration,
+        same(typeProvider.numType.getMethod('abs')));
   }
 
   test_visitPrefixedIdentifier_dynamic() async {
-    DartType dynamicType = _typeProvider.dynamicType;
-    var target = AstTestFactory.identifier3("a");
-    VariableElementImpl variable = ElementFactory.localVariableElement(target);
-    variable.type = dynamicType;
-    target.staticElement = variable;
-    target.staticType = dynamicType;
-    PrefixedIdentifier identifier =
-        AstTestFactory.identifier(target, AstTestFactory.identifier3("b"));
-    _resolveNode(identifier);
+    await assertNoErrorsInCode('''
+test(dynamic a) => a.b;
+''');
+    var identifier = findNode.prefixed('a.b');
     expect(identifier.staticElement, isNull);
     expect(identifier.identifier.staticElement, isNull);
-    _listener.assertNoErrors();
+  }
+
+  test_visitRedirectingConstructorInvocation_named() async {
+    await assertNoErrorsInCode('''
+class C {
+  C(int x) : this.named(x /*usage*/);
+  C.named(int y);
+}
+''');
+    var invocation = findNode.redirectingConstructorInvocation('this');
+    var namedConstructor = findElement.constructor('named', of: 'C');
+    expect(invocation.staticElement, namedConstructor);
+    expect(invocation.constructorName!.staticElement, namedConstructor);
+    expect(findNode.simple('x /*usage*/').staticParameterElement,
+        findElement.parameter('y'));
+  }
+
+  test_visitRedirectingConstructorInvocation_unnamed() async {
+    await assertNoErrorsInCode('''
+class C {
+  C.named(int x) : this(x /*usage*/);
+  C(int y);
+}
+''');
+    expect(findNode.redirectingConstructorInvocation('this').staticElement,
+        findElement.unnamedConstructor('C'));
+    expect(findNode.simple('x /*usage*/').staticParameterElement,
+        findElement.parameter('y'));
   }
 
   test_visitSuperConstructorInvocation() async {
-    ClassElementImpl superclass = ElementFactory.classElement2("A");
-    _encloseElement(superclass);
-    ConstructorElementImpl superConstructor =
-        ElementFactory.constructorElement2(superclass, null);
-    superclass.constructors = <ConstructorElement>[superConstructor];
-    ClassElementImpl subclass =
-        ElementFactory.classElement("B", interfaceTypeStar(superclass));
-    _encloseElement(subclass);
-    ConstructorElementImpl subConstructor =
-        ElementFactory.constructorElement2(subclass, null);
-    subclass.constructors = <ConstructorElement>[subConstructor];
-    SuperConstructorInvocation invocation =
-        AstTestFactory.superConstructorInvocation();
-    AstTestFactory.classDeclaration(null, 'C', null, null, null, null, [
-      AstTestFactory.constructorDeclaration(AstTestFactory.identifier3('C'),
-          null, AstTestFactory.formalParameterList(), [invocation])
-    ]);
-    _resolveInClass(invocation, subclass);
-    expect(invocation.staticElement, superConstructor);
-    _listener.assertNoErrors();
+    await assertNoErrorsInCode('''
+class A {}
+class B extends A {
+  B() : super();
+}
+''');
+    expect(findNode.superConstructorInvocation('super').staticElement,
+        findElement.unnamedConstructor('A'));
   }
 
   test_visitSuperConstructorInvocation_namedParameter() async {
-    ClassElementImpl superclass = ElementFactory.classElement2("A");
-    _encloseElement(superclass);
-    ConstructorElementImpl superConstructor =
-        ElementFactory.constructorElement2(superclass, null);
-    String parameterName = "p";
-    ParameterElement parameter = ElementFactory.namedParameter(parameterName);
-    superConstructor.parameters = <ParameterElement>[parameter];
-    superclass.constructors = <ConstructorElement>[superConstructor];
-    ClassElementImpl subclass =
-        ElementFactory.classElement("B", interfaceTypeStar(superclass));
-    _encloseElement(subclass);
-    ConstructorElementImpl subConstructor =
-        ElementFactory.constructorElement2(subclass, null);
-    subclass.constructors = <ConstructorElement>[subConstructor];
-    SuperConstructorInvocation invocation =
-        AstTestFactory.superConstructorInvocation([
-      AstTestFactory.namedExpression2(parameterName, AstTestFactory.integer(0))
-    ]);
-    AstTestFactory.classDeclaration(null, 'C', null, null, null, null, [
-      AstTestFactory.constructorDeclaration(AstTestFactory.identifier3('C'),
-          null, AstTestFactory.formalParameterList(), [invocation])
-    ]);
-    _resolveInClass(invocation, subclass);
-    expect(invocation.staticElement, superConstructor);
-    expect(
-        (invocation.argumentList.arguments[0] as NamedExpression)
-            .name
-            .label
-            .staticElement,
-        same(parameter));
-    _listener.assertNoErrors();
-  }
-
-  /// Create and return the resolver used by the tests.
-  void _createResolver() {
-    var context = TestAnalysisContext();
-    _typeProvider = context.typeProviderLegacy;
-
-    Source source = FileSource(getFile("/test.dart"));
-    CompilationUnitElementImpl unit = CompilationUnitElementImpl();
-    unit.librarySource = unit.source = source;
-    _definingLibrary = ElementFactory.library(context, "test");
-    _definingLibrary.definingCompilationUnit = unit;
-
-    _definingLibrary.typeProvider = context.typeProviderLegacy;
-    _definingLibrary.typeSystem = context.typeSystemLegacy;
-    var inheritance = InheritanceManager3();
-
-    var featureSet = FeatureSet.latestLanguageVersion();
-    _visitor = ResolverVisitor(
-        inheritance, _definingLibrary, source, _typeProvider, _listener,
-        featureSet: featureSet,
-        flowAnalysisHelper:
-            FlowAnalysisHelper(context.typeSystemLegacy, false, featureSet));
-    _resolver = _visitor.elementResolver;
-  }
-
-  void _encloseElement(ElementImpl element) {
-    if (element is ClassElement) {
-      element.enclosingElement = _definingLibrary;
-    }
-  }
-
-  /// Return the element associated with the label of [statement] after the
-  /// resolver has resolved it.  [labelElement] is the label element to be
-  /// defined in the statement's label scope, and [labelTarget] is the statement
-  /// the label resolves to.
-  Element? _resolveBreak(BreakStatement statement,
-      LabelElementImpl labelElement, Statement labelTarget) {
-    _resolveStatement(statement, labelElement, labelTarget);
-    return statement.label!.staticElement;
-  }
-
-  /// Return the element associated with the label [statement] after the
-  /// resolver has resolved it.  [labelElement] is the label element to be
-  /// defined in the statement's label scope, and [labelTarget] is the AST node
-  /// the label resolves to.
-  ///
-  /// @param statement the statement to be resolved
-  /// @param labelElement the label element to be defined in the statement's
-  ///          label scope
-  /// @return the element to which the statement's label was resolved
-  Element? _resolveContinue(ContinueStatement statement,
-      LabelElementImpl labelElement, AstNode labelTarget) {
-    _resolveStatement(statement, labelElement, labelTarget);
-    return statement.label!.staticElement;
-  }
-
-  /// Return the element associated with the given identifier after the resolver
-  /// has resolved the identifier.
-  ///
-  /// @param node the expression to be resolved
-  /// @param enclosingClass the element representing the class enclosing the
-  ///          identifier
-  /// @return the element to which the expression was resolved
-  void _resolveInClass(AstNode node, ClassElement enclosingClass) {
-    try {
-      _visitor.enclosingClass = enclosingClass;
-      node.accept(_resolver);
-    } finally {
-      _visitor.enclosingClass = null;
-    }
-  }
-
-  /// Return the element associated with the given identifier after the resolver
-  /// has resolved the identifier.
-  ///
-  /// @param node the expression to be resolved
-  /// @param definedElements the elements that are to be defined in the scope in
-  ///          which the element is being resolved
-  /// @return the element to which the expression was resolved
-  void _resolveNode(AstNode node) {
-    node.accept(_resolver);
-  }
-
-  /// Return the element associated with the label of the given statement after
-  /// the resolver has resolved the statement.
-  ///
-  /// @param statement the statement to be resolved
-  /// @param labelElement the label element to be defined in the statement's
-  ///          label scope
-  /// @return the element to which the statement's label was resolved
-  void _resolveStatement(Statement statement, LabelElementImpl? labelElement,
-      AstNode? labelTarget) {
-    statement.accept(_resolver);
-  }
+    await assertNoErrorsInCode('''
+class A {
+  A({dynamic p});
 }
-
-class _LibraryElementMock implements LibraryElement {
-  @override
-  noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
+class B extends A {
+  B() : super(p: 0);
+}
+''');
+    expect(findNode.superConstructorInvocation('super').staticElement,
+        findElement.unnamedConstructor('A'));
+    expect(
+        findNode.simple('p:').staticElement, same(findElement.parameter('p')));
+  }
 }
diff --git a/pkg/analyzer/test/generated/non_error_resolver_test.dart b/pkg/analyzer/test/generated/non_error_resolver_test.dart
index bf708fc..8891e87 100644
--- a/pkg/analyzer/test/generated/non_error_resolver_test.dart
+++ b/pkg/analyzer/test/generated/non_error_resolver_test.dart
@@ -1451,6 +1451,26 @@
 ''');
   }
 
+  test_implicit_call_reference_in_top_level_type_inference() async {
+    // This test case is important because the variable `map` is subject to top
+    // level type inference, which means it gets resolved twice.  We need to
+    // make sure that on the second resolution pass, the resolver can handle the
+    // ImplicitCallReference node
+    await assertNoErrorsInCode(r'''
+typedef Object Func(Object x);
+
+class Bar {
+  int x = 42;
+
+  Object call(Object x) {
+    return 'Bar $x';
+  }
+}
+
+var map = <String, Func>{'bar': new Bar()};
+''');
+  }
+
   test_importDuplicatedLibraryName() async {
     newFile("$testPackageLibPath/lib.dart", content: "library lib;");
     await assertErrorsInCode(r'''
diff --git a/pkg/analyzer/test/generated/parser_fasta_listener.dart b/pkg/analyzer/test/generated/parser_fasta_listener.dart
index f40c8da..d588af2 100644
--- a/pkg/analyzer/test/generated/parser_fasta_listener.dart
+++ b/pkg/analyzer/test/generated/parser_fasta_listener.dart
@@ -87,8 +87,8 @@
 
   @override
   void beginClassDeclaration(
-      Token beginToken, Token? abstractToken, Token name) {
-    super.beginClassDeclaration(beginToken, abstractToken, name);
+      Token beginToken, Token? abstractToken, Token? macroToken, Token name) {
+    super.beginClassDeclaration(beginToken, abstractToken, macroToken, name);
     begin('ClassDeclaration');
   }
 
@@ -392,8 +392,9 @@
 
   @override
   void beginNamedMixinApplication(
-      Token beginToken, Token? abstractToken, Token name) {
-    super.beginNamedMixinApplication(beginToken, abstractToken, name);
+      Token beginToken, Token? abstractToken, Token? macroToken, Token name) {
+    super.beginNamedMixinApplication(
+        beginToken, abstractToken, macroToken, name);
     begin('NamedMixinApplication');
   }
 
diff --git a/pkg/analyzer/test/generated/parser_test_base.dart b/pkg/analyzer/test/generated/parser_test_base.dart
index aed3955..4c2d5a6 100644
--- a/pkg/analyzer/test/generated/parser_test_base.dart
+++ b/pkg/analyzer/test/generated/parser_test_base.dart
@@ -814,6 +814,7 @@
         null,
         null,
         null,
+        null,
         Token(Keyword.CLASS, 0),
         astFactory.simpleIdentifier(
             fasta.StringToken.fromString(TokenType.IDENTIFIER, className, 6)),
diff --git a/pkg/analyzer/test/generated/resolver_test_case.dart b/pkg/analyzer/test/generated/resolver_test_case.dart
index 385bb7d..ba05ff5 100644
--- a/pkg/analyzer/test/generated/resolver_test_case.dart
+++ b/pkg/analyzer/test/generated/resolver_test_case.dart
@@ -6,7 +6,6 @@
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
-import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:test/test.dart';
 
 import '../src/dart/resolution/context_collection_resolution.dart';
@@ -238,7 +237,10 @@
   }
 
   void _checkResolved(
-      AstNode node, Element? element, Predicate<Element>? predicate) {
+    AstNode node,
+    Element? element,
+    bool Function(Element)? predicate,
+  ) {
     if (element == null) {
       if (_knownExceptions == null || !_knownExceptions!.contains(node)) {
         _unresolvedNodes.add(node);
diff --git a/pkg/analyzer/test/generated/static_type_analyzer_test.dart b/pkg/analyzer/test/generated/static_type_analyzer_test.dart
index 6d3741a..145865a 100644
--- a/pkg/analyzer/test/generated/static_type_analyzer_test.dart
+++ b/pkg/analyzer/test/generated/static_type_analyzer_test.dart
@@ -5,7 +5,9 @@
 import 'package:analyzer/dart/analysis/features.dart';
 import 'package:analyzer/dart/analysis/session.dart';
 import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element.dart';
+import 'package:analyzer/dart/element/scope.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/dart/element/type_provider.dart';
 import 'package:analyzer/src/dart/ast/extensions.dart';
@@ -16,7 +18,6 @@
 import 'package:analyzer/src/dart/resolver/flow_analysis_visitor.dart';
 import 'package:analyzer/src/generated/resolver.dart' show ResolverVisitor;
 import 'package:analyzer/src/generated/source.dart';
-import 'package:analyzer/src/generated/static_type_analyzer.dart';
 import 'package:analyzer/src/generated/testing/ast_test_factory.dart';
 import 'package:analyzer/src/generated/testing/element_factory.dart';
 import 'package:analyzer/src/source/source_resource.dart';
@@ -54,8 +55,8 @@
   /// The library containing the code being resolved.
   late final LibraryElementImpl _definingLibrary;
 
-  /// The analyzer being used to analyze the test cases.
-  late final StaticTypeAnalyzer _analyzer;
+  /// The compilation unit containing the code being resolved.
+  late CompilationUnitElementImpl _definingCompilationUnit;
 
   /// The type provider used to access the types.
   late final TypeProvider _typeProvider;
@@ -272,8 +273,9 @@
 
   void test_visitCascadeExpression() {
     // a..length
-    Expression node = AstTestFactory.cascadeExpression(
-        _resolvedString("a"), [AstTestFactory.propertyAccess2(null, "length")]);
+    Expression node = AstTestFactory.cascadeExpression(_resolvedString("a"), [
+      AstTestFactory.propertyAccess2(null, "length", TokenType.PERIOD_PERIOD)
+    ]);
     expect(_analyze(node), same(_typeProvider.stringType));
     _listener.assertNoErrors();
   }
@@ -308,15 +310,17 @@
   void test_visitInstanceCreationExpression_named() {
     // new C.m()
     ClassElementImpl classElement = ElementFactory.classElement2("C");
+    _definingCompilationUnit.classes = [classElement];
     String constructorName = "m";
     ConstructorElementImpl constructor =
         ElementFactory.constructorElement2(classElement, constructorName);
     classElement.constructors = <ConstructorElement>[constructor];
     InstanceCreationExpression node =
         AstTestFactory.instanceCreationExpression2(
-            null,
-            AstTestFactory.namedType(classElement),
-            [AstTestFactory.identifier3(constructorName)]);
+            null, AstTestFactory.namedType(classElement), [
+      AstTestFactory.identifier3(constructorName)
+        ..scopeLookupResult = ScopeLookupResult(constructor, null)
+    ]);
     expect(_analyze(node), interfaceTypeStar(classElement));
     _listener.assertNoErrors();
   }
@@ -334,6 +338,7 @@
         typeArguments: [interfaceTypeStar(elementI)]);
     InstanceCreationExpression node =
         AstTestFactory.instanceCreationExpression2(null, typeName);
+    _definingCompilationUnit.classes = [elementC, elementI];
     InterfaceType type = _analyze(node) as InterfaceType;
     List<DartType> typeArgs = type.typeArguments;
     expect(typeArgs.length, 1);
@@ -344,6 +349,7 @@
   void test_visitInstanceCreationExpression_unnamed() {
     // new C()
     ClassElementImpl classElement = ElementFactory.classElement2("C");
+    _definingCompilationUnit.classes = [classElement];
     ConstructorElementImpl constructor =
         ElementFactory.constructorElement2(classElement, null);
     classElement.constructors = <ConstructorElement>[constructor];
@@ -434,6 +440,13 @@
     InterfaceType thisType =
         interfaceTypeStar(ElementFactory.classElement("B", superType));
     Expression node = AstTestFactory.superExpression();
+    // Place the super expression inside a method declaration
+    // (`test() => super.foo;`) so that we don't provoke a
+    // SUPER_IN_INVALID_CONTEXT error
+    AstTestFactory.methodDeclaration4(
+        name: 'test',
+        body: AstTestFactory.expressionFunctionBody(
+            AstTestFactory.propertyAccess2(node, 'foo')));
     expect(_analyze(node, thisType), same(thisType));
     _listener.assertNoErrors();
   }
@@ -466,7 +479,7 @@
     if (thisType != null) {
       _visitor.setThisInterfaceType(thisType);
     }
-    node.accept(_analyzer);
+    node.accept(_visitor);
     return node.typeOrThrow;
   }
 
@@ -499,15 +512,14 @@
     var context = TestAnalysisContext();
     var inheritance = InheritanceManager3();
     Source source = FileSource(getFile("/lib.dart"));
-    CompilationUnitElementImpl definingCompilationUnit =
-        CompilationUnitElementImpl();
-    definingCompilationUnit.librarySource =
-        definingCompilationUnit.source = source;
+    _definingCompilationUnit = CompilationUnitElementImpl();
+    _definingCompilationUnit.librarySource =
+        _definingCompilationUnit.source = source;
     var featureSet = FeatureSet.latestLanguageVersion();
 
     _definingLibrary = LibraryElementImpl(
         context, _AnalysisSessionMock(), 'name', -1, 0, featureSet);
-    _definingLibrary.definingCompilationUnit = definingCompilationUnit;
+    _definingLibrary.definingCompilationUnit = _definingCompilationUnit;
 
     _definingLibrary.typeProvider = context.typeProviderLegacy;
     _definingLibrary.typeSystem = context.typeSystemLegacy;
@@ -518,7 +530,6 @@
         featureSet: featureSet,
         flowAnalysisHelper:
             FlowAnalysisHelper(context.typeSystemLegacy, false, featureSet));
-    _analyzer = _visitor.typeAnalyzer;
   }
 
   DartType _flatten(DartType type) => _typeSystem.flatten(type);
diff --git a/pkg/analyzer/test/generated/utilities_test.dart b/pkg/analyzer/test/generated/utilities_test.dart
index 20115cd..cd93433 100644
--- a/pkg/analyzer/test/generated/utilities_test.dart
+++ b/pkg/analyzer/test/generated/utilities_test.dart
@@ -7,11 +7,8 @@
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/src/dart/analysis/experiments.dart';
-import 'package:analyzer/src/dart/ast/ast_factory.dart';
 import 'package:analyzer/src/dart/ast/utilities.dart';
-import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/source.dart';
-import 'package:analyzer/src/generated/testing/ast_test_factory.dart';
 import 'package:analyzer/src/generated/utilities_collection.dart';
 import 'package:analyzer/src/test_utilities/find_node.dart';
 import 'package:test/test.dart';
@@ -23,7 +20,6 @@
     defineReflectiveTests(LineInfoTest);
     defineReflectiveTests(NodeReplacerTest);
     defineReflectiveTests(SourceRangeTest);
-    defineReflectiveTests(StringUtilitiesTest);
   });
 }
 
@@ -116,923 +112,6 @@
   }
 }
 
-class Getter_NodeReplacerTest_test_annotation
-    implements NodeReplacerTest_Getter<Annotation, ArgumentList> {
-  @override
-  ArgumentList? get(Annotation node) => node.arguments;
-}
-
-class Getter_NodeReplacerTest_test_annotation_2
-    implements NodeReplacerTest_Getter<Annotation, Identifier> {
-  @override
-  Identifier get(Annotation node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_annotation_3
-    implements NodeReplacerTest_Getter<Annotation, SimpleIdentifier> {
-  @override
-  SimpleIdentifier? get(Annotation node) => node.constructorName;
-}
-
-class Getter_NodeReplacerTest_test_annotation_4
-    implements NodeReplacerTest_Getter<Annotation, TypeArgumentList> {
-  @override
-  TypeArgumentList? get(Annotation node) => node.typeArguments;
-}
-
-class Getter_NodeReplacerTest_test_asExpression
-    implements NodeReplacerTest_Getter<AsExpression, TypeAnnotation> {
-  @override
-  TypeAnnotation? get(AsExpression node) => node.type;
-}
-
-class Getter_NodeReplacerTest_test_asExpression_2
-    implements NodeReplacerTest_Getter<AsExpression, Expression> {
-  @override
-  Expression get(AsExpression node) => node.expression;
-}
-
-class Getter_NodeReplacerTest_test_assertStatement
-    implements NodeReplacerTest_Getter<AssertStatement, Expression> {
-  @override
-  Expression get(AssertStatement node) => node.condition;
-}
-
-class Getter_NodeReplacerTest_test_assertStatement_2
-    implements NodeReplacerTest_Getter<AssertStatement, Expression> {
-  @override
-  Expression? get(AssertStatement node) => node.message;
-}
-
-class Getter_NodeReplacerTest_test_assignmentExpression
-    implements NodeReplacerTest_Getter<AssignmentExpression, Expression> {
-  @override
-  Expression get(AssignmentExpression node) => node.rightHandSide;
-}
-
-class Getter_NodeReplacerTest_test_assignmentExpression_2
-    implements NodeReplacerTest_Getter<AssignmentExpression, Expression> {
-  @override
-  Expression get(AssignmentExpression node) => node.leftHandSide;
-}
-
-class Getter_NodeReplacerTest_test_awaitExpression
-    implements NodeReplacerTest_Getter<AwaitExpression, Expression> {
-  @override
-  Expression get(AwaitExpression node) => node.expression;
-}
-
-class Getter_NodeReplacerTest_test_binaryExpression
-    implements NodeReplacerTest_Getter<BinaryExpression, Expression> {
-  @override
-  Expression get(BinaryExpression node) => node.leftOperand;
-}
-
-class Getter_NodeReplacerTest_test_binaryExpression_2
-    implements NodeReplacerTest_Getter<BinaryExpression, Expression> {
-  @override
-  Expression get(BinaryExpression node) => node.rightOperand;
-}
-
-class Getter_NodeReplacerTest_test_blockFunctionBody
-    implements NodeReplacerTest_Getter<BlockFunctionBody, Block> {
-  @override
-  Block get(BlockFunctionBody node) => node.block;
-}
-
-class Getter_NodeReplacerTest_test_breakStatement
-    implements NodeReplacerTest_Getter<BreakStatement, SimpleIdentifier> {
-  @override
-  SimpleIdentifier? get(BreakStatement node) => node.label;
-}
-
-class Getter_NodeReplacerTest_test_cascadeExpression
-    implements NodeReplacerTest_Getter<CascadeExpression, Expression> {
-  @override
-  Expression get(CascadeExpression node) => node.target;
-}
-
-class Getter_NodeReplacerTest_test_classDeclaration
-    implements NodeReplacerTest_Getter<ClassDeclaration, ImplementsClause> {
-  @override
-  ImplementsClause? get(ClassDeclaration node) => node.implementsClause;
-}
-
-class Getter_NodeReplacerTest_test_classDeclaration_2
-    implements NodeReplacerTest_Getter<ClassDeclaration, WithClause> {
-  @override
-  WithClause? get(ClassDeclaration node) => node.withClause;
-}
-
-class Getter_NodeReplacerTest_test_classDeclaration_3
-    implements NodeReplacerTest_Getter<ClassDeclaration, NativeClause> {
-  @override
-  NativeClause? get(ClassDeclaration node) => node.nativeClause;
-}
-
-class Getter_NodeReplacerTest_test_classDeclaration_4
-    implements NodeReplacerTest_Getter<ClassDeclaration, ExtendsClause> {
-  @override
-  ExtendsClause? get(ClassDeclaration node) => node.extendsClause;
-}
-
-class Getter_NodeReplacerTest_test_classDeclaration_5
-    implements NodeReplacerTest_Getter<ClassDeclaration, TypeParameterList> {
-  @override
-  TypeParameterList? get(ClassDeclaration node) => node.typeParameters;
-}
-
-class Getter_NodeReplacerTest_test_classDeclaration_6
-    implements NodeReplacerTest_Getter<ClassDeclaration, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(ClassDeclaration node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_classTypeAlias
-    implements NodeReplacerTest_Getter<ClassTypeAlias, NamedType> {
-  @override
-  NamedType get(ClassTypeAlias node) => node.superclass2;
-}
-
-class Getter_NodeReplacerTest_test_classTypeAlias_2
-    implements NodeReplacerTest_Getter<ClassTypeAlias, ImplementsClause> {
-  @override
-  ImplementsClause? get(ClassTypeAlias node) => node.implementsClause;
-}
-
-class Getter_NodeReplacerTest_test_classTypeAlias_3
-    implements NodeReplacerTest_Getter<ClassTypeAlias, WithClause> {
-  @override
-  WithClause get(ClassTypeAlias node) => node.withClause;
-}
-
-class Getter_NodeReplacerTest_test_classTypeAlias_4
-    implements NodeReplacerTest_Getter<ClassTypeAlias, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(ClassTypeAlias node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_classTypeAlias_5
-    implements NodeReplacerTest_Getter<ClassTypeAlias, TypeParameterList> {
-  @override
-  TypeParameterList? get(ClassTypeAlias node) => node.typeParameters;
-}
-
-class Getter_NodeReplacerTest_test_commentReference
-    implements
-        NodeReplacerTest_Getter<CommentReference, CommentReferableExpression> {
-  @override
-  CommentReferableExpression get(CommentReference node) => node.expression;
-}
-
-class Getter_NodeReplacerTest_test_compilationUnit
-    implements NodeReplacerTest_Getter<CompilationUnit, ScriptTag> {
-  @override
-  ScriptTag? get(CompilationUnit node) => node.scriptTag;
-}
-
-class Getter_NodeReplacerTest_test_conditionalExpression
-    implements NodeReplacerTest_Getter<ConditionalExpression, Expression> {
-  @override
-  Expression get(ConditionalExpression node) => node.elseExpression;
-}
-
-class Getter_NodeReplacerTest_test_conditionalExpression_2
-    implements NodeReplacerTest_Getter<ConditionalExpression, Expression> {
-  @override
-  Expression get(ConditionalExpression node) => node.thenExpression;
-}
-
-class Getter_NodeReplacerTest_test_conditionalExpression_3
-    implements NodeReplacerTest_Getter<ConditionalExpression, Expression> {
-  @override
-  Expression get(ConditionalExpression node) => node.condition;
-}
-
-class Getter_NodeReplacerTest_test_constructorDeclaration
-    implements
-        NodeReplacerTest_Getter<ConstructorDeclaration, ConstructorName> {
-  @override
-  ConstructorName? get(ConstructorDeclaration node) =>
-      node.redirectedConstructor;
-}
-
-class Getter_NodeReplacerTest_test_constructorDeclaration_2
-    implements
-        NodeReplacerTest_Getter<ConstructorDeclaration, SimpleIdentifier> {
-  @override
-  SimpleIdentifier? get(ConstructorDeclaration node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_constructorDeclaration_3
-    implements NodeReplacerTest_Getter<ConstructorDeclaration, Identifier> {
-  @override
-  Identifier get(ConstructorDeclaration node) => node.returnType;
-}
-
-class Getter_NodeReplacerTest_test_constructorDeclaration_4
-    implements
-        NodeReplacerTest_Getter<ConstructorDeclaration, FormalParameterList> {
-  @override
-  FormalParameterList get(ConstructorDeclaration node) => node.parameters;
-}
-
-class Getter_NodeReplacerTest_test_constructorDeclaration_5
-    implements NodeReplacerTest_Getter<ConstructorDeclaration, FunctionBody> {
-  @override
-  FunctionBody? get(ConstructorDeclaration node) => node.body;
-}
-
-class Getter_NodeReplacerTest_test_constructorFieldInitializer
-    implements
-        NodeReplacerTest_Getter<ConstructorFieldInitializer, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(ConstructorFieldInitializer node) => node.fieldName;
-}
-
-class Getter_NodeReplacerTest_test_constructorFieldInitializer_2
-    implements
-        NodeReplacerTest_Getter<ConstructorFieldInitializer, Expression> {
-  @override
-  Expression get(ConstructorFieldInitializer node) => node.expression;
-}
-
-class Getter_NodeReplacerTest_test_constructorName
-    implements NodeReplacerTest_Getter<ConstructorName, NamedType> {
-  @override
-  NamedType get(ConstructorName node) => node.type2;
-}
-
-class Getter_NodeReplacerTest_test_constructorName_2
-    implements NodeReplacerTest_Getter<ConstructorName, SimpleIdentifier> {
-  @override
-  SimpleIdentifier? get(ConstructorName node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_continueStatement
-    implements NodeReplacerTest_Getter<ContinueStatement, SimpleIdentifier> {
-  @override
-  SimpleIdentifier? get(ContinueStatement node) => node.label;
-}
-
-class Getter_NodeReplacerTest_test_declaredIdentifier
-    implements NodeReplacerTest_Getter<DeclaredIdentifier, TypeAnnotation> {
-  @override
-  TypeAnnotation? get(DeclaredIdentifier node) => node.type;
-}
-
-class Getter_NodeReplacerTest_test_declaredIdentifier_2
-    implements NodeReplacerTest_Getter<DeclaredIdentifier, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(DeclaredIdentifier node) => node.identifier;
-}
-
-class Getter_NodeReplacerTest_test_defaultFormalParameter
-    implements
-        NodeReplacerTest_Getter<DefaultFormalParameter, NormalFormalParameter> {
-  @override
-  NormalFormalParameter get(DefaultFormalParameter node) => node.parameter;
-}
-
-class Getter_NodeReplacerTest_test_defaultFormalParameter_2
-    implements NodeReplacerTest_Getter<DefaultFormalParameter, Expression> {
-  @override
-  Expression? get(DefaultFormalParameter node) => node.defaultValue;
-}
-
-class Getter_NodeReplacerTest_test_doStatement
-    implements NodeReplacerTest_Getter<DoStatement, Expression> {
-  @override
-  Expression get(DoStatement node) => node.condition;
-}
-
-class Getter_NodeReplacerTest_test_doStatement_2
-    implements NodeReplacerTest_Getter<DoStatement, Statement> {
-  @override
-  Statement get(DoStatement node) => node.body;
-}
-
-class Getter_NodeReplacerTest_test_enumConstantDeclaration
-    implements
-        NodeReplacerTest_Getter<EnumConstantDeclaration, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(EnumConstantDeclaration node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_enumDeclaration
-    implements NodeReplacerTest_Getter<EnumDeclaration, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(EnumDeclaration node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_expressionFunctionBody
-    implements NodeReplacerTest_Getter<ExpressionFunctionBody, Expression> {
-  @override
-  Expression get(ExpressionFunctionBody node) => node.expression;
-}
-
-class Getter_NodeReplacerTest_test_expressionStatement
-    implements NodeReplacerTest_Getter<ExpressionStatement, Expression> {
-  @override
-  Expression get(ExpressionStatement node) => node.expression;
-}
-
-class Getter_NodeReplacerTest_test_extendsClause
-    implements NodeReplacerTest_Getter<ExtendsClause, NamedType> {
-  @override
-  NamedType get(ExtendsClause node) => node.superclass2;
-}
-
-class Getter_NodeReplacerTest_test_fieldDeclaration
-    implements
-        NodeReplacerTest_Getter<FieldDeclaration, VariableDeclarationList> {
-  @override
-  VariableDeclarationList get(FieldDeclaration node) => node.fields;
-}
-
-class Getter_NodeReplacerTest_test_fieldFormalParameter
-    implements
-        NodeReplacerTest_Getter<FieldFormalParameter, FormalParameterList> {
-  @override
-  FormalParameterList? get(FieldFormalParameter node) => node.parameters;
-}
-
-class Getter_NodeReplacerTest_test_fieldFormalParameter_2
-    implements NodeReplacerTest_Getter<FieldFormalParameter, TypeAnnotation> {
-  @override
-  TypeAnnotation? get(FieldFormalParameter node) => node.type;
-}
-
-class Getter_NodeReplacerTest_test_forEachStatement_withIdentifier
-    implements NodeReplacerTest_Getter<ForStatement, Statement> {
-  @override
-  Statement get(ForStatement node) => node.body;
-}
-
-class Getter_NodeReplacerTest_test_forEachStatement_withIdentifier_2
-    implements NodeReplacerTest_Getter<ForStatement, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(ForStatement node) =>
-      (node.forLoopParts as ForEachPartsWithIdentifier).identifier;
-}
-
-class Getter_NodeReplacerTest_test_forEachStatement_withIdentifier_3
-    implements NodeReplacerTest_Getter<ForStatement, Expression> {
-  @override
-  Expression get(ForStatement node) =>
-      (node.forLoopParts as ForEachParts).iterable;
-}
-
-class Getter_NodeReplacerTest_test_forEachStatement_withLoopVariable
-    implements NodeReplacerTest_Getter<ForStatement, Expression> {
-  @override
-  Expression get(ForStatement node) =>
-      (node.forLoopParts as ForEachParts).iterable;
-}
-
-class Getter_NodeReplacerTest_test_forEachStatement_withLoopVariable_2
-    implements NodeReplacerTest_Getter<ForStatement, DeclaredIdentifier> {
-  @override
-  DeclaredIdentifier get(ForStatement node) =>
-      (node.forLoopParts as ForEachPartsWithDeclaration).loopVariable;
-}
-
-class Getter_NodeReplacerTest_test_forEachStatement_withLoopVariable_3
-    implements NodeReplacerTest_Getter<ForStatement, Statement> {
-  @override
-  Statement get(ForStatement node) => node.body;
-}
-
-class Getter_NodeReplacerTest_test_forStatement_withInitialization
-    implements NodeReplacerTest_Getter<ForStatement, Statement> {
-  @override
-  Statement get(ForStatement node) => node.body;
-}
-
-class Getter_NodeReplacerTest_test_forStatement_withInitialization_2
-    implements NodeReplacerTest_Getter<ForStatement, Expression> {
-  @override
-  Expression? get(ForStatement node) =>
-      (node.forLoopParts as ForParts).condition;
-}
-
-class Getter_NodeReplacerTest_test_forStatement_withInitialization_3
-    implements NodeReplacerTest_Getter<ForStatement, Expression> {
-  @override
-  Expression? get(ForStatement node) =>
-      (node.forLoopParts as ForPartsWithExpression).initialization;
-}
-
-class Getter_NodeReplacerTest_test_forStatement_withVariables
-    implements NodeReplacerTest_Getter<ForStatement, Statement> {
-  @override
-  Statement get(ForStatement node) => node.body;
-}
-
-class Getter_NodeReplacerTest_test_forStatement_withVariables_2
-    implements NodeReplacerTest_Getter<ForStatement, VariableDeclarationList> {
-  @override
-  VariableDeclarationList get(ForStatement node) =>
-      (node.forLoopParts as ForPartsWithDeclarations).variables;
-}
-
-class Getter_NodeReplacerTest_test_forStatement_withVariables_3
-    implements NodeReplacerTest_Getter<ForStatement, Expression> {
-  @override
-  Expression? get(ForStatement node) =>
-      (node.forLoopParts as ForParts).condition;
-}
-
-class Getter_NodeReplacerTest_test_functionDeclaration
-    implements NodeReplacerTest_Getter<FunctionDeclaration, TypeAnnotation> {
-  @override
-  TypeAnnotation? get(FunctionDeclaration node) => node.returnType;
-}
-
-class Getter_NodeReplacerTest_test_functionDeclaration_2
-    implements
-        NodeReplacerTest_Getter<FunctionDeclaration, FunctionExpression> {
-  @override
-  FunctionExpression get(FunctionDeclaration node) => node.functionExpression;
-}
-
-class Getter_NodeReplacerTest_test_functionDeclaration_3
-    implements NodeReplacerTest_Getter<FunctionDeclaration, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(FunctionDeclaration node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_functionDeclarationStatement
-    implements
-        NodeReplacerTest_Getter<FunctionDeclarationStatement,
-            FunctionDeclaration> {
-  @override
-  FunctionDeclaration get(FunctionDeclarationStatement node) =>
-      node.functionDeclaration;
-}
-
-class Getter_NodeReplacerTest_test_functionExpression
-    implements
-        NodeReplacerTest_Getter<FunctionExpression, FormalParameterList> {
-  @override
-  FormalParameterList? get(FunctionExpression node) => node.parameters;
-}
-
-class Getter_NodeReplacerTest_test_functionExpression_2
-    implements NodeReplacerTest_Getter<FunctionExpression, FunctionBody> {
-  @override
-  FunctionBody? get(FunctionExpression node) => node.body;
-}
-
-class Getter_NodeReplacerTest_test_functionExpressionInvocation
-    implements
-        NodeReplacerTest_Getter<FunctionExpressionInvocation, Expression> {
-  @override
-  Expression get(FunctionExpressionInvocation node) => node.function;
-}
-
-class Getter_NodeReplacerTest_test_functionExpressionInvocation_2
-    implements
-        NodeReplacerTest_Getter<FunctionExpressionInvocation, ArgumentList> {
-  @override
-  ArgumentList get(FunctionExpressionInvocation node) => node.argumentList;
-}
-
-class Getter_NodeReplacerTest_test_functionTypeAlias
-    implements NodeReplacerTest_Getter<FunctionTypeAlias, TypeParameterList> {
-  @override
-  TypeParameterList? get(FunctionTypeAlias node) => node.typeParameters;
-}
-
-class Getter_NodeReplacerTest_test_functionTypeAlias_2
-    implements NodeReplacerTest_Getter<FunctionTypeAlias, FormalParameterList> {
-  @override
-  FormalParameterList get(FunctionTypeAlias node) => node.parameters;
-}
-
-class Getter_NodeReplacerTest_test_functionTypeAlias_3
-    implements NodeReplacerTest_Getter<FunctionTypeAlias, TypeAnnotation> {
-  @override
-  TypeAnnotation? get(FunctionTypeAlias node) => node.returnType;
-}
-
-class Getter_NodeReplacerTest_test_functionTypeAlias_4
-    implements NodeReplacerTest_Getter<FunctionTypeAlias, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(FunctionTypeAlias node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_functionTypedFormalParameter
-    implements
-        NodeReplacerTest_Getter<FunctionTypedFormalParameter, TypeAnnotation> {
-  @override
-  TypeAnnotation? get(FunctionTypedFormalParameter node) => node.returnType;
-}
-
-class Getter_NodeReplacerTest_test_functionTypedFormalParameter_2
-    implements
-        NodeReplacerTest_Getter<FunctionTypedFormalParameter,
-            FormalParameterList> {
-  @override
-  FormalParameterList get(FunctionTypedFormalParameter node) => node.parameters;
-}
-
-class Getter_NodeReplacerTest_test_ifStatement
-    implements NodeReplacerTest_Getter<IfStatement, Expression> {
-  @override
-  Expression get(IfStatement node) => node.condition;
-}
-
-class Getter_NodeReplacerTest_test_ifStatement_2
-    implements NodeReplacerTest_Getter<IfStatement, Statement> {
-  @override
-  Statement? get(IfStatement node) => node.elseStatement;
-}
-
-class Getter_NodeReplacerTest_test_ifStatement_3
-    implements NodeReplacerTest_Getter<IfStatement, Statement> {
-  @override
-  Statement get(IfStatement node) => node.thenStatement;
-}
-
-class Getter_NodeReplacerTest_test_importDirective
-    implements NodeReplacerTest_Getter<ImportDirective, SimpleIdentifier> {
-  @override
-  SimpleIdentifier? get(ImportDirective node) => node.prefix;
-}
-
-class Getter_NodeReplacerTest_test_indexExpression
-    implements NodeReplacerTest_Getter<IndexExpression, Expression> {
-  @override
-  Expression? get(IndexExpression node) => node.target;
-}
-
-class Getter_NodeReplacerTest_test_indexExpression_2
-    implements NodeReplacerTest_Getter<IndexExpression, Expression> {
-  @override
-  Expression get(IndexExpression node) => node.index;
-}
-
-class Getter_NodeReplacerTest_test_instanceCreationExpression
-    implements
-        NodeReplacerTest_Getter<InstanceCreationExpression, ArgumentList> {
-  @override
-  ArgumentList get(InstanceCreationExpression node) => node.argumentList;
-}
-
-class Getter_NodeReplacerTest_test_instanceCreationExpression_2
-    implements
-        NodeReplacerTest_Getter<InstanceCreationExpression, ConstructorName> {
-  @override
-  ConstructorName get(InstanceCreationExpression node) => node.constructorName;
-}
-
-class Getter_NodeReplacerTest_test_interpolationExpression
-    implements NodeReplacerTest_Getter<InterpolationExpression, Expression> {
-  @override
-  Expression get(InterpolationExpression node) => node.expression;
-}
-
-class Getter_NodeReplacerTest_test_isExpression
-    implements NodeReplacerTest_Getter<IsExpression, Expression> {
-  @override
-  Expression get(IsExpression node) => node.expression;
-}
-
-class Getter_NodeReplacerTest_test_isExpression_2
-    implements NodeReplacerTest_Getter<IsExpression, TypeAnnotation> {
-  @override
-  TypeAnnotation? get(IsExpression node) => node.type;
-}
-
-class Getter_NodeReplacerTest_test_label
-    implements NodeReplacerTest_Getter<Label, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(Label node) => node.label;
-}
-
-class Getter_NodeReplacerTest_test_labeledStatement
-    implements NodeReplacerTest_Getter<LabeledStatement, Statement> {
-  @override
-  Statement get(LabeledStatement node) => node.statement;
-}
-
-class Getter_NodeReplacerTest_test_libraryDirective
-    implements NodeReplacerTest_Getter<LibraryDirective, LibraryIdentifier> {
-  @override
-  LibraryIdentifier get(LibraryDirective node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_mapLiteralEntry
-    implements NodeReplacerTest_Getter<MapLiteralEntry, Expression> {
-  @override
-  Expression get(MapLiteralEntry node) => node.value;
-}
-
-class Getter_NodeReplacerTest_test_mapLiteralEntry_2
-    implements NodeReplacerTest_Getter<MapLiteralEntry, Expression> {
-  @override
-  Expression get(MapLiteralEntry node) => node.key;
-}
-
-class Getter_NodeReplacerTest_test_methodDeclaration
-    implements NodeReplacerTest_Getter<MethodDeclaration, TypeAnnotation> {
-  @override
-  TypeAnnotation? get(MethodDeclaration node) => node.returnType;
-}
-
-class Getter_NodeReplacerTest_test_methodDeclaration_2
-    implements NodeReplacerTest_Getter<MethodDeclaration, FunctionBody> {
-  @override
-  FunctionBody get(MethodDeclaration node) => node.body;
-}
-
-class Getter_NodeReplacerTest_test_methodDeclaration_3
-    implements NodeReplacerTest_Getter<MethodDeclaration, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(MethodDeclaration node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_methodDeclaration_4
-    implements NodeReplacerTest_Getter<MethodDeclaration, FormalParameterList> {
-  @override
-  FormalParameterList? get(MethodDeclaration node) => node.parameters;
-}
-
-class Getter_NodeReplacerTest_test_methodInvocation
-    implements NodeReplacerTest_Getter<MethodInvocation, ArgumentList> {
-  @override
-  ArgumentList get(MethodInvocation node) => node.argumentList;
-}
-
-class Getter_NodeReplacerTest_test_methodInvocation_2
-    implements NodeReplacerTest_Getter<MethodInvocation, Expression> {
-  @override
-  Expression? get(MethodInvocation node) => node.target;
-}
-
-class Getter_NodeReplacerTest_test_methodInvocation_3
-    implements NodeReplacerTest_Getter<MethodInvocation, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(MethodInvocation node) => node.methodName;
-}
-
-class Getter_NodeReplacerTest_test_namedExpression
-    implements NodeReplacerTest_Getter<NamedExpression, Label> {
-  @override
-  Label get(NamedExpression node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_namedExpression_2
-    implements NodeReplacerTest_Getter<NamedExpression, Expression> {
-  @override
-  Expression get(NamedExpression node) => node.expression;
-}
-
-class Getter_NodeReplacerTest_test_nativeClause
-    implements NodeReplacerTest_Getter<NativeClause, StringLiteral> {
-  @override
-  StringLiteral? get(NativeClause node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_nativeFunctionBody
-    implements NodeReplacerTest_Getter<NativeFunctionBody, StringLiteral> {
-  @override
-  StringLiteral? get(NativeFunctionBody node) => node.stringLiteral;
-}
-
-class Getter_NodeReplacerTest_test_parenthesizedExpression
-    implements NodeReplacerTest_Getter<ParenthesizedExpression, Expression> {
-  @override
-  Expression get(ParenthesizedExpression node) => node.expression;
-}
-
-class Getter_NodeReplacerTest_test_partOfDirective
-    implements NodeReplacerTest_Getter<PartOfDirective, LibraryIdentifier> {
-  @override
-  LibraryIdentifier? get(PartOfDirective node) => node.libraryName;
-}
-
-class Getter_NodeReplacerTest_test_postfixExpression
-    implements NodeReplacerTest_Getter<PostfixExpression, Expression> {
-  @override
-  Expression get(PostfixExpression node) => node.operand;
-}
-
-class Getter_NodeReplacerTest_test_prefixedIdentifier
-    implements NodeReplacerTest_Getter<PrefixedIdentifier, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(PrefixedIdentifier node) => node.identifier;
-}
-
-class Getter_NodeReplacerTest_test_prefixedIdentifier_2
-    implements NodeReplacerTest_Getter<PrefixedIdentifier, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(PrefixedIdentifier node) => node.prefix;
-}
-
-class Getter_NodeReplacerTest_test_prefixExpression
-    implements NodeReplacerTest_Getter<PrefixExpression, Expression> {
-  @override
-  Expression get(PrefixExpression node) => node.operand;
-}
-
-class Getter_NodeReplacerTest_test_propertyAccess
-    implements NodeReplacerTest_Getter<PropertyAccess, Expression> {
-  @override
-  Expression? get(PropertyAccess node) => node.target;
-}
-
-class Getter_NodeReplacerTest_test_propertyAccess_2
-    implements NodeReplacerTest_Getter<PropertyAccess, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(PropertyAccess node) => node.propertyName;
-}
-
-class Getter_NodeReplacerTest_test_redirectingConstructorInvocation
-    implements
-        NodeReplacerTest_Getter<RedirectingConstructorInvocation,
-            SimpleIdentifier> {
-  @override
-  SimpleIdentifier? get(RedirectingConstructorInvocation node) =>
-      node.constructorName;
-}
-
-class Getter_NodeReplacerTest_test_redirectingConstructorInvocation_2
-    implements
-        NodeReplacerTest_Getter<RedirectingConstructorInvocation,
-            ArgumentList> {
-  @override
-  ArgumentList get(RedirectingConstructorInvocation node) => node.argumentList;
-}
-
-class Getter_NodeReplacerTest_test_returnStatement
-    implements NodeReplacerTest_Getter<ReturnStatement, Expression> {
-  @override
-  Expression? get(ReturnStatement node) => node.expression;
-}
-
-class Getter_NodeReplacerTest_test_simpleFormalParameter
-    implements NodeReplacerTest_Getter<SimpleFormalParameter, TypeAnnotation> {
-  @override
-  TypeAnnotation? get(SimpleFormalParameter node) => node.type;
-}
-
-class Getter_NodeReplacerTest_test_superConstructorInvocation
-    implements
-        NodeReplacerTest_Getter<SuperConstructorInvocation, SimpleIdentifier> {
-  @override
-  SimpleIdentifier? get(SuperConstructorInvocation node) =>
-      node.constructorName;
-}
-
-class Getter_NodeReplacerTest_test_superConstructorInvocation_2
-    implements
-        NodeReplacerTest_Getter<SuperConstructorInvocation, ArgumentList> {
-  @override
-  ArgumentList get(SuperConstructorInvocation node) => node.argumentList;
-}
-
-class Getter_NodeReplacerTest_test_switchCase
-    implements NodeReplacerTest_Getter<SwitchCase, Expression> {
-  @override
-  Expression get(SwitchCase node) => node.expression;
-}
-
-class Getter_NodeReplacerTest_test_switchStatement
-    implements NodeReplacerTest_Getter<SwitchStatement, Expression> {
-  @override
-  Expression get(SwitchStatement node) => node.expression;
-}
-
-class Getter_NodeReplacerTest_test_throwExpression
-    implements NodeReplacerTest_Getter<ThrowExpression, Expression> {
-  @override
-  Expression get(ThrowExpression node) => node.expression;
-}
-
-class Getter_NodeReplacerTest_test_topLevelVariableDeclaration
-    implements
-        NodeReplacerTest_Getter<TopLevelVariableDeclaration,
-            VariableDeclarationList> {
-  @override
-  VariableDeclarationList get(TopLevelVariableDeclaration node) =>
-      node.variables;
-}
-
-class Getter_NodeReplacerTest_test_tryStatement
-    implements NodeReplacerTest_Getter<TryStatement, Block> {
-  @override
-  Block? get(TryStatement node) => node.finallyBlock;
-}
-
-class Getter_NodeReplacerTest_test_tryStatement_2
-    implements NodeReplacerTest_Getter<TryStatement, Block> {
-  @override
-  Block get(TryStatement node) => node.body;
-}
-
-class Getter_NodeReplacerTest_test_typeName
-    implements NodeReplacerTest_Getter<NamedType, TypeArgumentList> {
-  @override
-  TypeArgumentList? get(NamedType node) => node.typeArguments;
-}
-
-class Getter_NodeReplacerTest_test_typeName_2
-    implements NodeReplacerTest_Getter<NamedType, Identifier> {
-  @override
-  Identifier get(NamedType node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_typeParameter
-    implements NodeReplacerTest_Getter<TypeParameter, TypeAnnotation> {
-  @override
-  TypeAnnotation? get(TypeParameter node) => node.bound;
-}
-
-class Getter_NodeReplacerTest_test_typeParameter_2
-    implements NodeReplacerTest_Getter<TypeParameter, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(TypeParameter node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_variableDeclaration
-    implements NodeReplacerTest_Getter<VariableDeclaration, SimpleIdentifier> {
-  @override
-  SimpleIdentifier get(VariableDeclaration node) => node.name;
-}
-
-class Getter_NodeReplacerTest_test_variableDeclaration_2
-    implements NodeReplacerTest_Getter<VariableDeclaration, Expression> {
-  @override
-  Expression? get(VariableDeclaration node) => node.initializer;
-}
-
-class Getter_NodeReplacerTest_test_variableDeclarationList
-    implements
-        NodeReplacerTest_Getter<VariableDeclarationList, TypeAnnotation> {
-  @override
-  TypeAnnotation? get(VariableDeclarationList node) => node.type;
-}
-
-class Getter_NodeReplacerTest_test_variableDeclarationStatement
-    implements
-        NodeReplacerTest_Getter<VariableDeclarationStatement,
-            VariableDeclarationList> {
-  @override
-  VariableDeclarationList get(VariableDeclarationStatement node) =>
-      node.variables;
-}
-
-class Getter_NodeReplacerTest_test_whileStatement
-    implements NodeReplacerTest_Getter<WhileStatement, Expression> {
-  @override
-  Expression get(WhileStatement node) => node.condition;
-}
-
-class Getter_NodeReplacerTest_test_whileStatement_2
-    implements NodeReplacerTest_Getter<WhileStatement, Statement> {
-  @override
-  Statement get(WhileStatement node) => node.body;
-}
-
-class Getter_NodeReplacerTest_test_yieldStatement
-    implements NodeReplacerTest_Getter<YieldStatement, Expression> {
-  @override
-  Expression get(YieldStatement node) => node.expression;
-}
-
-class Getter_NodeReplacerTest_testAnnotatedNode
-    implements NodeReplacerTest_Getter<AnnotatedNode, Comment> {
-  @override
-  Comment? get(AnnotatedNode node) => node.documentationComment;
-}
-
-class Getter_NodeReplacerTest_testNormalFormalParameter
-    implements
-        NodeReplacerTest_Getter<NormalFormalParameter, SimpleIdentifier> {
-  @override
-  SimpleIdentifier? get(NormalFormalParameter node) => node.identifier;
-}
-
-class Getter_NodeReplacerTest_testNormalFormalParameter_2
-    implements NodeReplacerTest_Getter<NormalFormalParameter, Comment> {
-  @override
-  Comment? get(NormalFormalParameter node) => node.documentationComment;
-}
-
-class Getter_NodeReplacerTest_testTypedLiteral
-    implements NodeReplacerTest_Getter<TypedLiteral, TypeArgumentList> {
-  @override
-  TypeArgumentList? get(TypedLiteral node) => node.typeArguments;
-}
-
-class Getter_NodeReplacerTest_testUriBasedDirective
-    implements NodeReplacerTest_Getter<UriBasedDirective, StringLiteral> {
-  @override
-  StringLiteral get(UriBasedDirective node) => node.uri;
-}
-
 @reflectiveTest
 class LineInfoTest {
   void test_creation() {
@@ -1045,6 +124,21 @@
     }, throwsArgumentError);
   }
 
+  void test_fromContent_n() {
+    var lineInfo = LineInfo.fromContent('a\nbb\nccc');
+    expect(lineInfo.lineStarts, <int>[0, 2, 5]);
+  }
+
+  void test_fromContent_r() {
+    var lineInfo = LineInfo.fromContent('a\rbb\rccc');
+    expect(lineInfo.lineStarts, <int>[0, 2, 5]);
+  }
+
+  void test_fromContent_rn() {
+    var lineInfo = LineInfo.fromContent('a\r\nbb\r\nccc');
+    expect(lineInfo.lineStarts, <int>[0, 3, 7]);
+  }
+
   void test_getLocation_firstLine() {
     LineInfo info = LineInfo(<int>[0, 12, 34]);
     var location = info.getLocation(4);
@@ -1084,379 +178,212 @@
   }
 }
 
-class ListGetter_NodeReplacerTest_test_adjacentStrings
-    extends NodeReplacerTest_ListGetter<AdjacentStrings, StringLiteral> {
-  ListGetter_NodeReplacerTest_test_adjacentStrings(int arg0) : super(arg0);
-
-  @override
-  NodeList<StringLiteral> getList(AdjacentStrings node) => node.strings;
-}
-
-class ListGetter_NodeReplacerTest_test_adjacentStrings_2
-    extends NodeReplacerTest_ListGetter<AdjacentStrings, StringLiteral> {
-  ListGetter_NodeReplacerTest_test_adjacentStrings_2(int arg0) : super(arg0);
-
-  @override
-  NodeList<StringLiteral> getList(AdjacentStrings node) => node.strings;
-}
-
-class ListGetter_NodeReplacerTest_test_argumentList
-    extends NodeReplacerTest_ListGetter<ArgumentList, Expression> {
-  ListGetter_NodeReplacerTest_test_argumentList(int arg0) : super(arg0);
-
-  @override
-  NodeList<Expression> getList(ArgumentList node) => node.arguments;
-}
-
-class ListGetter_NodeReplacerTest_test_block
-    extends NodeReplacerTest_ListGetter<Block, Statement> {
-  ListGetter_NodeReplacerTest_test_block(int arg0) : super(arg0);
-
-  @override
-  NodeList<Statement> getList(Block node) => node.statements;
-}
-
-class ListGetter_NodeReplacerTest_test_cascadeExpression
-    extends NodeReplacerTest_ListGetter<CascadeExpression, Expression> {
-  ListGetter_NodeReplacerTest_test_cascadeExpression(int arg0) : super(arg0);
-
-  @override
-  NodeList<Expression> getList(CascadeExpression node) => node.cascadeSections;
-}
-
-class ListGetter_NodeReplacerTest_test_classDeclaration
-    extends NodeReplacerTest_ListGetter<ClassDeclaration, ClassMember> {
-  ListGetter_NodeReplacerTest_test_classDeclaration(int arg0) : super(arg0);
-
-  @override
-  NodeList<ClassMember> getList(ClassDeclaration node) => node.members;
-}
-
-class ListGetter_NodeReplacerTest_test_comment
-    extends NodeReplacerTest_ListGetter<Comment, CommentReference> {
-  ListGetter_NodeReplacerTest_test_comment(int arg0) : super(arg0);
-
-  @override
-  NodeList<CommentReference> getList(Comment node) => node.references;
-}
-
-class ListGetter_NodeReplacerTest_test_compilationUnit
-    extends NodeReplacerTest_ListGetter<CompilationUnit, Directive> {
-  ListGetter_NodeReplacerTest_test_compilationUnit(int arg0) : super(arg0);
-
-  @override
-  NodeList<Directive> getList(CompilationUnit node) => node.directives;
-}
-
-class ListGetter_NodeReplacerTest_test_compilationUnit_2
-    extends NodeReplacerTest_ListGetter<CompilationUnit,
-        CompilationUnitMember> {
-  ListGetter_NodeReplacerTest_test_compilationUnit_2(int arg0) : super(arg0);
-
-  @override
-  NodeList<CompilationUnitMember> getList(CompilationUnit node) =>
-      node.declarations;
-}
-
-class ListGetter_NodeReplacerTest_test_constructorDeclaration
-    extends NodeReplacerTest_ListGetter<ConstructorDeclaration,
-        ConstructorInitializer> {
-  ListGetter_NodeReplacerTest_test_constructorDeclaration(int arg0)
-      : super(arg0);
-
-  @override
-  NodeList<ConstructorInitializer> getList(ConstructorDeclaration node) =>
-      node.initializers;
-}
-
-class ListGetter_NodeReplacerTest_test_formalParameterList
-    extends NodeReplacerTest_ListGetter<FormalParameterList, FormalParameter> {
-  ListGetter_NodeReplacerTest_test_formalParameterList(int arg0) : super(arg0);
-
-  @override
-  NodeList<FormalParameter> getList(FormalParameterList node) =>
-      node.parameters;
-}
-
-class ListGetter_NodeReplacerTest_test_forStatement_withInitialization
-    extends NodeReplacerTest_ListGetter<ForStatement, Expression> {
-  ListGetter_NodeReplacerTest_test_forStatement_withInitialization(int arg0)
-      : super(arg0);
-
-  @override
-  NodeList<Expression> getList(ForStatement node) =>
-      (node.forLoopParts as ForParts).updaters;
-}
-
-class ListGetter_NodeReplacerTest_test_forStatement_withVariables
-    extends NodeReplacerTest_ListGetter<ForStatement, Expression> {
-  ListGetter_NodeReplacerTest_test_forStatement_withVariables(int arg0)
-      : super(arg0);
-
-  @override
-  NodeList<Expression> getList(ForStatement node) =>
-      (node.forLoopParts as ForParts).updaters;
-}
-
-class ListGetter_NodeReplacerTest_test_hideCombinator
-    extends NodeReplacerTest_ListGetter<HideCombinator, SimpleIdentifier> {
-  ListGetter_NodeReplacerTest_test_hideCombinator(int arg0) : super(arg0);
-
-  @override
-  NodeList<SimpleIdentifier> getList(HideCombinator node) => node.hiddenNames;
-}
-
-class ListGetter_NodeReplacerTest_test_implementsClause
-    extends NodeReplacerTest_ListGetter<ImplementsClause, NamedType> {
-  ListGetter_NodeReplacerTest_test_implementsClause(int arg0) : super(arg0);
-
-  @override
-  NodeList<NamedType> getList(ImplementsClause node) => node.interfaces2;
-}
-
-class ListGetter_NodeReplacerTest_test_labeledStatement
-    extends NodeReplacerTest_ListGetter<LabeledStatement, Label> {
-  ListGetter_NodeReplacerTest_test_labeledStatement(int arg0) : super(arg0);
-
-  @override
-  NodeList<Label> getList(LabeledStatement node) => node.labels;
-}
-
-class ListGetter_NodeReplacerTest_test_libraryIdentifier
-    extends NodeReplacerTest_ListGetter<LibraryIdentifier, SimpleIdentifier> {
-  ListGetter_NodeReplacerTest_test_libraryIdentifier(int arg0) : super(arg0);
-
-  @override
-  NodeList<SimpleIdentifier> getList(LibraryIdentifier node) => node.components;
-}
-
-class ListGetter_NodeReplacerTest_test_listLiteral
-    extends NodeReplacerTest_ListGetter<ListLiteral, CollectionElement> {
-  ListGetter_NodeReplacerTest_test_listLiteral(int arg0) : super(arg0);
-
-  @override
-  NodeList<CollectionElement> getList(ListLiteral node) => node.elements;
-}
-
-class ListGetter_NodeReplacerTest_test_mapLiteral
-    extends NodeReplacerTest_ListGetter<SetOrMapLiteral, CollectionElement> {
-  ListGetter_NodeReplacerTest_test_mapLiteral(int arg0) : super(arg0);
-
-  @override
-  NodeList<CollectionElement> getList(SetOrMapLiteral node) => node.elements;
-}
-
-class ListGetter_NodeReplacerTest_test_showCombinator
-    extends NodeReplacerTest_ListGetter<ShowCombinator, SimpleIdentifier> {
-  ListGetter_NodeReplacerTest_test_showCombinator(int arg0) : super(arg0);
-
-  @override
-  NodeList<SimpleIdentifier> getList(ShowCombinator node) => node.shownNames;
-}
-
-class ListGetter_NodeReplacerTest_test_stringInterpolation
-    extends NodeReplacerTest_ListGetter<StringInterpolation,
-        InterpolationElement> {
-  ListGetter_NodeReplacerTest_test_stringInterpolation(int arg0) : super(arg0);
-
-  @override
-  NodeList<InterpolationElement> getList(StringInterpolation node) =>
-      node.elements;
-}
-
-class ListGetter_NodeReplacerTest_test_switchStatement
-    extends NodeReplacerTest_ListGetter<SwitchStatement, SwitchMember> {
-  ListGetter_NodeReplacerTest_test_switchStatement(int arg0) : super(arg0);
-
-  @override
-  NodeList<SwitchMember> getList(SwitchStatement node) => node.members;
-}
-
-class ListGetter_NodeReplacerTest_test_tryStatement
-    extends NodeReplacerTest_ListGetter<TryStatement, CatchClause> {
-  ListGetter_NodeReplacerTest_test_tryStatement(int arg0) : super(arg0);
-
-  @override
-  NodeList<CatchClause> getList(TryStatement node) => node.catchClauses;
-}
-
-class ListGetter_NodeReplacerTest_test_typeArgumentList
-    extends NodeReplacerTest_ListGetter<TypeArgumentList, TypeAnnotation> {
-  ListGetter_NodeReplacerTest_test_typeArgumentList(int arg0) : super(arg0);
-
-  @override
-  NodeList<TypeAnnotation> getList(TypeArgumentList node) => node.arguments;
-}
-
-class ListGetter_NodeReplacerTest_test_typeParameterList
-    extends NodeReplacerTest_ListGetter<TypeParameterList, TypeParameter> {
-  ListGetter_NodeReplacerTest_test_typeParameterList(int arg0) : super(arg0);
-
-  @override
-  NodeList<TypeParameter> getList(TypeParameterList node) =>
-      node.typeParameters;
-}
-
-class ListGetter_NodeReplacerTest_test_variableDeclarationList
-    extends NodeReplacerTest_ListGetter<VariableDeclarationList,
-        VariableDeclaration> {
-  ListGetter_NodeReplacerTest_test_variableDeclarationList(int arg0)
-      : super(arg0);
-
-  @override
-  NodeList<VariableDeclaration> getList(VariableDeclarationList node) =>
-      node.variables;
-}
-
-class ListGetter_NodeReplacerTest_test_withClause
-    extends NodeReplacerTest_ListGetter<WithClause, NamedType> {
-  ListGetter_NodeReplacerTest_test_withClause(int arg0) : super(arg0);
-
-  @override
-  NodeList<NamedType> getList(WithClause node) => node.mixinTypes2;
-}
-
-class ListGetter_NodeReplacerTest_testAnnotatedNode
-    extends NodeReplacerTest_ListGetter<AnnotatedNode, Annotation> {
-  ListGetter_NodeReplacerTest_testAnnotatedNode(int arg0) : super(arg0);
-
-  @override
-  NodeList<Annotation> getList(AnnotatedNode node) => node.metadata;
-}
-
-class ListGetter_NodeReplacerTest_testNamespaceDirective
-    extends NodeReplacerTest_ListGetter<NamespaceDirective, Combinator> {
-  ListGetter_NodeReplacerTest_testNamespaceDirective(int arg0) : super(arg0);
-
-  @override
-  NodeList<Combinator> getList(NamespaceDirective node) => node.combinators;
-}
-
-class ListGetter_NodeReplacerTest_testNormalFormalParameter
-    extends NodeReplacerTest_ListGetter<NormalFormalParameter, Annotation> {
-  ListGetter_NodeReplacerTest_testNormalFormalParameter(int arg0) : super(arg0);
-
-  @override
-  NodeList<Annotation> getList(NormalFormalParameter node) => node.metadata;
-}
-
-class ListGetter_NodeReplacerTest_testSwitchMember
-    extends NodeReplacerTest_ListGetter<SwitchMember, Label> {
-  ListGetter_NodeReplacerTest_testSwitchMember(int arg0) : super(arg0);
-
-  @override
-  NodeList<Label> getList(SwitchMember node) => node.labels;
-}
-
-class ListGetter_NodeReplacerTest_testSwitchMember_2
-    extends NodeReplacerTest_ListGetter<SwitchMember, Statement> {
-  ListGetter_NodeReplacerTest_testSwitchMember_2(int arg0) : super(arg0);
-
-  @override
-  NodeList<Statement> getList(SwitchMember node) => node.statements;
-}
-
 @reflectiveTest
 class NodeReplacerTest {
-  /// An empty list of tokens.
-  static const List<Token> EMPTY_TOKEN_LIST = <Token>[];
-
   void test_adjacentStrings() {
-    AdjacentStrings node = AstTestFactory.adjacentStrings(
-        [AstTestFactory.string2("a"), AstTestFactory.string2("b")]);
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_adjacentStrings_2(0));
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_adjacentStrings(1));
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  'aaa' 'bbb';
+}
+''');
+    var adjacentStrings = findNode.adjacentStrings('aaa');
+    _assertReplaceInList(
+      destination: adjacentStrings,
+      child: adjacentStrings.strings[0],
+      replacement: adjacentStrings.strings[1],
+    );
   }
 
   void test_annotation() {
-    Annotation node = AstTestFactory.annotation2(
-        AstTestFactory.identifier3("C"),
-        AstTestFactory.identifier3("c"),
-        AstTestFactory.argumentList([AstTestFactory.integer(0)]));
-    _assertReplace(node, Getter_NodeReplacerTest_test_annotation());
-    _assertReplace(node, Getter_NodeReplacerTest_test_annotation_3());
-    _assertReplace(node, Getter_NodeReplacerTest_test_annotation_2());
-  }
-
-  void test_annotation_generic() {
-    Annotation node = AstTestFactory.annotation2(
-        AstTestFactory.identifier3("C"),
-        AstTestFactory.identifier3("c"),
-        AstTestFactory.argumentList([AstTestFactory.integer(0)]),
-        typeArguments:
-            AstTestFactory.typeArgumentList2([AstTestFactory.namedType4('T')]));
-    _assertReplace(node, Getter_NodeReplacerTest_test_annotation());
-    _assertReplace(node, Getter_NodeReplacerTest_test_annotation_3());
-    _assertReplace(node, Getter_NodeReplacerTest_test_annotation_2());
+    var findNode = _parseStringToFindNode(r'''
+@prefix.A<int>.named(args)
+@prefix.B<double>.named(args)
+void f() {}
+''');
+    _assertReplacementForChildren<Annotation>(
+      destination: findNode.annotation('prefix.A'),
+      source: findNode.annotation('prefix.B'),
+      childAccessors: [
+        (node) => node.arguments!,
+        (node) => node.constructorName!,
+        (node) => node.name,
+        (node) => node.typeArguments!,
+      ],
+    );
   }
 
   void test_argumentList() {
-    ArgumentList node =
-        AstTestFactory.argumentList([AstTestFactory.integer(0)]);
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_argumentList(0));
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  g(0, 1);
+}
+''');
+    var argumentList = findNode.argumentList('(0, 1)');
+    _assertReplaceInList(
+      destination: argumentList,
+      child: argumentList.arguments[0],
+      replacement: argumentList.arguments[1],
+    );
   }
 
   void test_asExpression() {
-    AsExpression node = AstTestFactory.asExpression(
-        AstTestFactory.integer(0),
-        AstTestFactory.namedType3(
-            AstTestFactory.identifier3("a"), [AstTestFactory.namedType4("C")]));
-    _assertReplace(node, Getter_NodeReplacerTest_test_asExpression_2());
-    _assertReplace(node, Getter_NodeReplacerTest_test_asExpression());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  0 as int;
+  1 as int;
+}
+''');
+    _assertReplacementForChildren<AsExpression>(
+      destination: findNode.as_('0 as'),
+      source: findNode.as_('1 as'),
+      childAccessors: [
+        (node) => node.expression,
+        (node) => node.type,
+      ],
+    );
   }
 
   void test_assertStatement() {
-    AssertStatement node = AstTestFactory.assertStatement(
-        AstTestFactory.booleanLiteral(true), AstTestFactory.string2('foo'));
-    _assertReplace(node, Getter_NodeReplacerTest_test_assertStatement());
-    _assertReplace(node, Getter_NodeReplacerTest_test_assertStatement_2());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  assert(true, 'first');
+  assert(true, 'second');
+}
+''');
+    _assertReplacementForChildren<AssertStatement>(
+      destination: findNode.assertStatement('first'),
+      source: findNode.assertStatement('second'),
+      childAccessors: [
+        (node) => node.condition,
+        (node) => node.message!,
+      ],
+    );
   }
 
   void test_assignmentExpression() {
-    AssignmentExpression node = AstTestFactory.assignmentExpression(
-        AstTestFactory.identifier3("l"),
-        TokenType.EQ,
-        AstTestFactory.identifier3("r"));
-    _assertReplace(node, Getter_NodeReplacerTest_test_assignmentExpression_2());
-    _assertReplace(node, Getter_NodeReplacerTest_test_assignmentExpression());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  a = 0;
+  b = 1;
+}
+''');
+    _assertReplacementForChildren<AssignmentExpression>(
+      destination: findNode.assignment('a ='),
+      source: findNode.assignment('b ='),
+      childAccessors: [
+        (node) => node.leftHandSide,
+        (node) => node.rightHandSide,
+      ],
+    );
   }
 
   void test_awaitExpression() {
-    var node = AstTestFactory.awaitExpression(AstTestFactory.identifier3("A"));
-    _assertReplace(node, Getter_NodeReplacerTest_test_awaitExpression());
+    var findNode = _parseStringToFindNode(r'''
+void f() async {
+  await 0;
+  await 1;
+}
+''');
+    _assertReplacementForChildren<AwaitExpression>(
+      destination: findNode.awaitExpression('0'),
+      source: findNode.awaitExpression('1'),
+      childAccessors: [
+        (node) => node.expression,
+      ],
+    );
   }
 
   void test_binaryExpression() {
-    BinaryExpression node = AstTestFactory.binaryExpression(
-        AstTestFactory.identifier3("l"),
-        TokenType.PLUS,
-        AstTestFactory.identifier3("r"));
-    _assertReplace(node, Getter_NodeReplacerTest_test_binaryExpression());
-    _assertReplace(node, Getter_NodeReplacerTest_test_binaryExpression_2());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  0 + 1;
+  1 + 2;
+}
+''');
+    _assertReplacementForChildren<BinaryExpression>(
+      destination: findNode.binary('0 + 1'),
+      source: findNode.binary('1 + 2'),
+      childAccessors: [
+        (node) => node.leftOperand,
+        (node) => node.rightOperand,
+      ],
+    );
   }
 
   void test_block() {
-    Block node = AstTestFactory.block([AstTestFactory.emptyStatement()]);
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_block(0));
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  print(0);
+  print(1);
+}
+''');
+    var block = findNode.block('{');
+    _assertReplaceInList(
+      destination: block,
+      child: block.statements[0],
+      replacement: block.statements[1],
+    );
   }
 
   void test_blockFunctionBody() {
-    BlockFunctionBody node =
-        AstTestFactory.blockFunctionBody(AstTestFactory.block());
-    _assertReplace(node, Getter_NodeReplacerTest_test_blockFunctionBody());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  print('fff');
+}
+
+void g() {
+  print('ggg');
+}
+''');
+    _assertReplacementForChildren<BlockFunctionBody>(
+      destination: findNode.blockFunctionBody('fff'),
+      source: findNode.blockFunctionBody('ggg'),
+      childAccessors: [
+        (node) => node.block,
+        (node) => node.block,
+      ],
+    );
   }
 
   void test_breakStatement() {
-    BreakStatement node = AstTestFactory.breakStatement2("l");
-    _assertReplace(node, Getter_NodeReplacerTest_test_breakStatement());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  while (true) {
+    break first;
+    break second;
+  }
+}
+''');
+    _assertReplacementForChildren<BreakStatement>(
+      destination: findNode.breakStatement('first'),
+      source: findNode.breakStatement('second'),
+      childAccessors: [
+        (node) => node.label!,
+      ],
+    );
   }
 
   void test_cascadeExpression() {
-    CascadeExpression node = AstTestFactory.cascadeExpression(
-        AstTestFactory.integer(0),
-        [AstTestFactory.propertyAccess(null, AstTestFactory.identifier3("b"))]);
-    _assertReplace(node, Getter_NodeReplacerTest_test_cascadeExpression());
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_cascadeExpression(0));
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  0..foo..bar;
+  1..foo;
+}
+''');
+    var cascadeExpression = findNode.cascade('0');
+    _assertReplaceInList(
+      destination: cascadeExpression,
+      child: cascadeExpression.cascadeSections[0],
+      replacement: cascadeExpression.cascadeSections[1],
+    );
+
+    _assertReplacementForChildren<CascadeExpression>(
+      destination: findNode.cascade('0'),
+      source: findNode.cascade('1'),
+      childAccessors: [
+        (node) => node.target,
+      ],
+    );
   }
 
   void test_catchClause() {
@@ -1466,10 +393,10 @@
   try {} on E2 catch (e2, st2) {}
 }
 ''');
-    _assertReplace2<CatchClause>(
+    _assertReplacementForChildren<CatchClause>(
       destination: findNode.catchClause('(e,'),
       source: findNode.catchClause('(e2,'),
-      getters: [
+      childAccessors: [
         (node) => node.exceptionType!,
         (node) => node.exceptionParameter!,
         (node) => node.stackTraceParameter!,
@@ -1479,649 +406,1268 @@
   }
 
   void test_classDeclaration() {
-    var node = AstTestFactory.classDeclaration(
-        null,
-        "A",
-        AstTestFactory.typeParameterList(["E"]),
-        AstTestFactory.extendsClause(AstTestFactory.namedType4("B")),
-        AstTestFactory.withClause([AstTestFactory.namedType4("C")]),
-        AstTestFactory.implementsClause([AstTestFactory.namedType4("D")]), [
-      AstTestFactory.fieldDeclaration2(
-          false, null, [AstTestFactory.variableDeclaration("f")])
-    ]);
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    node.nativeClause = AstTestFactory.nativeClause("");
-    _assertReplace(node, Getter_NodeReplacerTest_test_classDeclaration_6());
-    _assertReplace(node, Getter_NodeReplacerTest_test_classDeclaration_5());
-    _assertReplace(node, Getter_NodeReplacerTest_test_classDeclaration_4());
-    _assertReplace(node, Getter_NodeReplacerTest_test_classDeclaration_2());
-    _assertReplace(node, Getter_NodeReplacerTest_test_classDeclaration());
-    _assertReplace(node, Getter_NodeReplacerTest_test_classDeclaration_3());
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_classDeclaration(0));
-    _testAnnotatedNode(node);
+    var findNode = _parseStringToFindNode(r'''
+/// Comment A.
+@myA1
+@myA2
+class A<T> extends A0 with M implements I {
+  void foo() {}
+  void bar() {}
+}
+
+/// Comment B.
+class B<U> extends B0 with N implements J {}
+''');
+    var A = findNode.classDeclaration('A<T>');
+    _assertAnnotatedNode(A);
+    _assertReplaceInList(
+      destination: A,
+      child: A.members[0],
+      replacement: A.members[1],
+    );
+    _assertReplacementForChildren<ClassDeclaration>(
+      destination: findNode.classDeclaration('A<T>'),
+      source: findNode.classDeclaration('B<U>'),
+      childAccessors: [
+        (node) => node.documentationComment!,
+        (node) => node.extendsClause!,
+        (node) => node.implementsClause!,
+        (node) => node.name,
+        (node) => node.typeParameters!,
+        (node) => node.withClause!,
+      ],
+    );
   }
 
   void test_classTypeAlias() {
-    var node = AstTestFactory.classTypeAlias(
-        "A",
-        AstTestFactory.typeParameterList(["E"]),
-        null,
-        AstTestFactory.namedType4("B"),
-        AstTestFactory.withClause([AstTestFactory.namedType4("C")]),
-        AstTestFactory.implementsClause([AstTestFactory.namedType4("D")]));
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    _assertReplace(node, Getter_NodeReplacerTest_test_classTypeAlias_4());
-    _assertReplace(node, Getter_NodeReplacerTest_test_classTypeAlias_5());
-    _assertReplace(node, Getter_NodeReplacerTest_test_classTypeAlias());
-    _assertReplace(node, Getter_NodeReplacerTest_test_classTypeAlias_3());
-    _assertReplace(node, Getter_NodeReplacerTest_test_classTypeAlias_2());
-    _testAnnotatedNode(node);
+    var findNode = _parseStringToFindNode(r'''
+/// Comment A.
+@myA1
+@myA2
+class A<T> = A0 with M implements I;
+
+/// Comment B.
+class B<U> = B0 with N implements J;
+''');
+    _assertAnnotatedNode(
+      findNode.classTypeAlias('A<T>'),
+    );
+    _assertReplacementForChildren<ClassTypeAlias>(
+      destination: findNode.classTypeAlias('A<T>'),
+      source: findNode.classTypeAlias('B<U>'),
+      childAccessors: [
+        (node) => node.documentationComment!,
+        (node) => node.superclass2,
+        (node) => node.implementsClause!,
+        (node) => node.name,
+        (node) => node.typeParameters!,
+        (node) => node.withClause,
+      ],
+    );
   }
 
   void test_comment() {
-    Comment node = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.references.add(
-        astFactory.commentReference(null, AstTestFactory.identifier3("x")));
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_comment(0));
+    var findNode = _parseStringToFindNode(r'''
+/// Has [foo] and [bar].
+void f() {}
+''');
+    var comment = findNode.comment('Has');
+    _assertReplaceInList(
+      destination: comment,
+      child: comment.references[0],
+      replacement: comment.references[1],
+    );
   }
 
   void test_commentReference() {
-    CommentReference node =
-        astFactory.commentReference(null, AstTestFactory.identifier3("x"));
-    _assertReplace(node, Getter_NodeReplacerTest_test_commentReference());
+    var findNode = _parseStringToFindNode(r'''
+/// Has [foo] and [bar].
+void f() {}
+''');
+    _assertReplacementForChildren<CommentReference>(
+      destination: findNode.commentReference('foo'),
+      source: findNode.commentReference('bar'),
+      childAccessors: [
+        (node) => node.expression,
+      ],
+    );
   }
 
   void test_compilationUnit() {
-    CompilationUnit node = AstTestFactory.compilationUnit8("", [
-      AstTestFactory.libraryDirective2("lib")
-    ], [
-      AstTestFactory.topLevelVariableDeclaration2(
-          null, [AstTestFactory.variableDeclaration("X")])
-    ]);
-    _assertReplace(node, Getter_NodeReplacerTest_test_compilationUnit());
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_compilationUnit(0));
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_compilationUnit_2(0));
+    var findNode = _parseStringToFindNode(r'''
+import 'a.dart';
+import 'b.dart';
+class A {}
+class B {}
+''');
+    var unit = findNode.unit;
+    _assertReplaceInList(
+      destination: unit,
+      child: unit.directives[0],
+      replacement: unit.directives[1],
+    );
+    _assertReplaceInList(
+      destination: unit,
+      child: unit.declarations[0],
+      replacement: unit.declarations[1],
+    );
   }
 
   void test_conditionalExpression() {
-    ConditionalExpression node = AstTestFactory.conditionalExpression(
-        AstTestFactory.booleanLiteral(true),
-        AstTestFactory.integer(0),
-        AstTestFactory.integer(1));
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_conditionalExpression_3());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_conditionalExpression_2());
-    _assertReplace(node, Getter_NodeReplacerTest_test_conditionalExpression());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  true ? 0 : 1;
+  false ? 2 : 3;
+}
+''');
+    _assertReplacementForChildren<ConditionalExpression>(
+      destination: findNode.conditionalExpression('true'),
+      source: findNode.conditionalExpression('false'),
+      childAccessors: [
+        (node) => node.condition,
+        (node) => node.thenExpression,
+        (node) => node.elseExpression,
+      ],
+    );
   }
 
   void test_constructorDeclaration() {
-    var node = AstTestFactory.constructorDeclaration2(
-        null,
-        null,
-        AstTestFactory.identifier3("C"),
-        "d",
-        AstTestFactory.formalParameterList(),
-        [
-          AstTestFactory.constructorFieldInitializer(
-              false, "x", AstTestFactory.integer(0))
-        ],
-        AstTestFactory.emptyFunctionBody());
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    node.redirectedConstructor =
-        AstTestFactory.constructorName(AstTestFactory.namedType4("B"), "a");
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_constructorDeclaration_3());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_constructorDeclaration_2());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_constructorDeclaration_4());
-    _assertReplace(node, Getter_NodeReplacerTest_test_constructorDeclaration());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_constructorDeclaration_5());
-    _assertReplace(
-        node, ListGetter_NodeReplacerTest_test_constructorDeclaration(0));
-    _testAnnotatedNode(node);
+    var findNode = _parseStringToFindNode(r'''
+class A {
+  @myA1
+  @myA2
+  A.named(int a) : b = 0, c = 1;
+}
+
+class B {
+  B.named(int b);
+}
+''');
+    _assertReplacementForChildren<ConstructorDeclaration>(
+      destination: findNode.constructor('A.named'),
+      source: findNode.constructor('B.named'),
+      childAccessors: [
+        (node) => node.body,
+        (node) => node.name!,
+        (node) => node.parameters,
+        (node) => node.returnType,
+      ],
+    );
+    _assertAnnotatedNode(
+      findNode.constructor('A.named'),
+    );
+  }
+
+  void test_constructorDeclaration_redirectedConstructor() {
+    var findNode = _parseStringToFindNode(r'''
+class A {
+  factory A() = R;
+}
+
+class B {
+  factory B() = R;
+}
+''');
+    _assertReplacementForChildren<ConstructorDeclaration>(
+      destination: findNode.constructor('factory A'),
+      source: findNode.constructor('factory B'),
+      childAccessors: [
+        (node) => node.redirectedConstructor!,
+      ],
+    );
   }
 
   void test_constructorFieldInitializer() {
-    ConstructorFieldInitializer node =
-        AstTestFactory.constructorFieldInitializer(
-            false, "f", AstTestFactory.integer(0));
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_constructorFieldInitializer());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_constructorFieldInitializer_2());
+    var findNode = _parseStringToFindNode(r'''
+class A {
+  A() : a = 0, b = 1;
+}
+''');
+    _assertReplacementForChildren<ConstructorFieldInitializer>(
+      destination: findNode.constructorFieldInitializer('a ='),
+      source: findNode.constructorFieldInitializer('b ='),
+      childAccessors: [
+        (node) => node.fieldName,
+        (node) => node.expression,
+      ],
+    );
   }
 
   void test_constructorName() {
-    ConstructorName node =
-        AstTestFactory.constructorName(AstTestFactory.namedType4("C"), "n");
-    _assertReplace(node, Getter_NodeReplacerTest_test_constructorName());
-    _assertReplace(node, Getter_NodeReplacerTest_test_constructorName_2());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  new prefix.A.foo();
+  new prefix.B.bar();
+}
+''');
+    _assertReplacementForChildren<ConstructorName>(
+      destination: findNode.constructorName('A.foo'),
+      source: findNode.constructorName('B.bar'),
+      childAccessors: [
+        (node) => node.type2,
+        (node) => node.name!,
+      ],
+    );
   }
 
   void test_continueStatement() {
-    ContinueStatement node = AstTestFactory.continueStatement("l");
-    _assertReplace(node, Getter_NodeReplacerTest_test_continueStatement());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  while (true) {
+    continue first;
+    continue second;
+  }
+}
+''');
+    _assertReplacementForChildren<ContinueStatement>(
+      destination: findNode.continueStatement('first'),
+      source: findNode.continueStatement('second'),
+      childAccessors: [
+        (node) => node.label!,
+      ],
+    );
   }
 
   void test_declaredIdentifier() {
-    var node =
-        AstTestFactory.declaredIdentifier4(AstTestFactory.namedType4("C"), "i");
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    _assertReplace(node, Getter_NodeReplacerTest_test_declaredIdentifier());
-    _assertReplace(node, Getter_NodeReplacerTest_test_declaredIdentifier_2());
-    _testAnnotatedNode(node);
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  for (int i in []) {}
+  for (double j in []) {}
+}
+''');
+    _assertReplacementForChildren<DeclaredIdentifier>(
+      destination: findNode.declaredIdentifier('i in'),
+      source: findNode.declaredIdentifier('j in'),
+      childAccessors: [
+        (node) => node.identifier,
+        (node) => node.type!,
+      ],
+    );
   }
 
   void test_defaultFormalParameter() {
-    DefaultFormalParameter node = AstTestFactory.positionalFormalParameter(
-        AstTestFactory.simpleFormalParameter3("p"), AstTestFactory.integer(0));
-    _assertReplace(node, Getter_NodeReplacerTest_test_defaultFormalParameter());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_defaultFormalParameter_2());
+    var findNode = _parseStringToFindNode(r'''
+void f({int a = 0, double b = 1}) {}
+''');
+    _assertReplacementForChildren<DefaultFormalParameter>(
+      destination: findNode.defaultParameter('a ='),
+      source: findNode.defaultParameter('b ='),
+      childAccessors: [
+        (node) => node.parameter,
+        (node) => node.defaultValue!,
+      ],
+    );
   }
 
   void test_doStatement() {
-    DoStatement node = AstTestFactory.doStatement(
-        AstTestFactory.block(), AstTestFactory.booleanLiteral(true));
-    _assertReplace(node, Getter_NodeReplacerTest_test_doStatement_2());
-    _assertReplace(node, Getter_NodeReplacerTest_test_doStatement());
+    var findNode = _parseStringToFindNode(r'''
+void f({int a = 0, double b = 1}) {}
+''');
+    _assertReplacementForChildren<DefaultFormalParameter>(
+      destination: findNode.defaultParameter('a ='),
+      source: findNode.defaultParameter('b ='),
+      childAccessors: [
+        (node) => node.parameter,
+        (node) => node.defaultValue!,
+      ],
+    );
   }
 
   void test_enumConstantDeclaration() {
-    EnumConstantDeclaration node = astFactory.enumConstantDeclaration(
-        astFactory.endOfLineComment(EMPTY_TOKEN_LIST),
-        [AstTestFactory.annotation(AstTestFactory.identifier3("a"))],
-        AstTestFactory.identifier3("C"));
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_enumConstantDeclaration());
-    _testAnnotatedNode(node);
+    var findNode = _parseStringToFindNode(r'''
+enum E {
+  @myA1
+  @myA2
+  aaa,
+  bbb;
+}
+''');
+    _assertAnnotatedNode(
+      findNode.enumConstantDeclaration('aaa'),
+    );
+    _assertReplacementForChildren<EnumConstantDeclaration>(
+      destination: findNode.enumConstantDeclaration('aaa'),
+      source: findNode.enumConstantDeclaration('bbb'),
+      childAccessors: [
+        (node) => node.name,
+      ],
+    );
   }
 
   void test_enumDeclaration() {
-    var node = AstTestFactory.enumDeclaration2("E", ["ONE", "TWO"]);
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    _assertReplace(node, Getter_NodeReplacerTest_test_enumDeclaration());
-    _testAnnotatedNode(node);
+    var findNode = _parseStringToFindNode(r'''
+enum E1<T> with M1 implements I1 {one, two}
+enum E2<U> with M2 implements I2 {one, two}
+''');
+    _assertReplacementForChildren<EnumDeclaration>(
+      destination: findNode.enumDeclaration('enum E1'),
+      source: findNode.enumDeclaration('enum E2'),
+      childAccessors: [
+        (node) => node.name,
+        (node) => node.typeParameters!,
+        (node) => node.withClause!,
+        (node) => node.implementsClause!,
+      ],
+    );
+  }
+
+  void test_enumDeclaration_constants() {
+    var findNode = _parseStringToFindNode(r'''
+enum E1 {one}
+enum E2 {two}
+''');
+    _assertReplaceInList(
+      destination: findNode.enumDeclaration('enum E1'),
+      child: findNode.enumConstantDeclaration('one'),
+      replacement: findNode.enumConstantDeclaration('two'),
+    );
+  }
+
+  void test_enumDeclaration_members() {
+    var findNode = _parseStringToFindNode(r'''
+enum E1 {one; void foo() {}}
+enum E2 {two; void bar() {}}
+''');
+    _assertReplaceInList(
+      destination: findNode.enumDeclaration('enum E1'),
+      child: findNode.methodDeclaration('foo'),
+      replacement: findNode.methodDeclaration('bar'),
+    );
   }
 
   void test_exportDirective() {
-    var node = AstTestFactory.exportDirective2("", [
-      AstTestFactory.hideCombinator2(["C"])
-    ]);
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    _testNamespaceDirective(node);
+    var findNode = _parseStringToFindNode(r'''
+@myA1
+@myA2
+export 'a.dart' hide A show B;
+export 'b.dart';
+''');
+    var export_a = findNode.export('a.dart');
+    _assertAnnotatedNode(export_a);
+    _assertReplaceInList(
+      destination: export_a,
+      child: export_a.combinators[0],
+      replacement: export_a.combinators[1],
+    );
+    _assertReplacementForChildren<ExportDirective>(
+      destination: findNode.export('a.dart'),
+      source: findNode.export('b.dart'),
+      childAccessors: [
+        (node) => node.uri,
+      ],
+    );
   }
 
   void test_expressionFunctionBody() {
-    ExpressionFunctionBody node =
-        AstTestFactory.expressionFunctionBody(AstTestFactory.integer(0));
-    _assertReplace(node, Getter_NodeReplacerTest_test_expressionFunctionBody());
+    var findNode = _parseStringToFindNode(r'''
+void f() => 0;
+void g() => 1;
+''');
+    _assertReplacementForChildren<ExpressionFunctionBody>(
+      destination: findNode.expressionFunctionBody('0'),
+      source: findNode.expressionFunctionBody('1'),
+      childAccessors: [
+        (node) => node.expression,
+      ],
+    );
   }
 
   void test_expressionStatement() {
-    ExpressionStatement node =
-        AstTestFactory.expressionStatement(AstTestFactory.integer(0));
-    _assertReplace(node, Getter_NodeReplacerTest_test_expressionStatement());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  0;
+  1;
+}
+''');
+    _assertReplacementForChildren<ExpressionStatement>(
+      destination: findNode.expressionStatement('0'),
+      source: findNode.expressionStatement('1'),
+      childAccessors: [
+        (node) => node.expression,
+      ],
+    );
   }
 
   void test_extendsClause() {
-    ExtendsClause node =
-        AstTestFactory.extendsClause(AstTestFactory.namedType4("S"));
-    _assertReplace(node, Getter_NodeReplacerTest_test_extendsClause());
+    var findNode = _parseStringToFindNode(r'''
+class A extends A0 {}
+class B extends B0 {}
+''');
+    _assertReplacementForChildren<ExtendsClause>(
+      destination: findNode.extendsClause('A0'),
+      source: findNode.extendsClause('B0'),
+      childAccessors: [
+        (node) => node.superclass2,
+      ],
+    );
   }
 
   void test_fieldDeclaration() {
-    var node = AstTestFactory.fieldDeclaration(
-        false,
-        null,
-        AstTestFactory.namedType4("C"),
-        [AstTestFactory.variableDeclaration("c")]);
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    _assertReplace(node, Getter_NodeReplacerTest_test_fieldDeclaration());
-    _testAnnotatedNode(node);
+    var findNode = _parseStringToFindNode(r'''
+class A {
+  @myA1
+  @myA2
+  int foo = 0;
+  int bar = 0;
+}
+class B extends B0 {}
+''');
+    _assertAnnotatedNode(
+      findNode.fieldDeclaration('foo'),
+    );
+    _assertReplacementForChildren<FieldDeclaration>(
+      destination: findNode.fieldDeclaration('foo'),
+      source: findNode.fieldDeclaration('bar'),
+      childAccessors: [
+        (node) => node.fields,
+      ],
+    );
   }
 
   void test_fieldFormalParameter() {
-    var node = AstTestFactory.fieldFormalParameter(
-        null,
-        AstTestFactory.namedType4("C"),
-        "f",
-        AstTestFactory.formalParameterList());
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata = [
-      AstTestFactory.annotation(AstTestFactory.identifier3("a"))
-    ];
-    _assertReplace(node, Getter_NodeReplacerTest_test_fieldFormalParameter_2());
-    _assertReplace(node, Getter_NodeReplacerTest_test_fieldFormalParameter());
-    _testNormalFormalParameter(node);
+    var findNode = _parseStringToFindNode(r'''
+class A {
+  A(
+    @myA1
+    @myA2
+    int this.foo<T>(int a),
+    int this.bar<U>(int b),
+  );
+}
+''');
+    var foo = findNode.fieldFormalParameter('foo');
+    _assertFormalParameterMetadata(foo);
+    _assertReplacementForChildren<FieldFormalParameter>(
+      destination: findNode.fieldFormalParameter('foo'),
+      source: findNode.fieldFormalParameter('bar'),
+      childAccessors: [
+        (node) => node.identifier,
+        (node) => node.parameters!,
+        (node) => node.type!,
+        (node) => node.typeParameters!,
+      ],
+    );
+  }
+
+  void test_forEachPartsWithDeclaration() {
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  for (int a in []) {}
+  for (int b in []) {}
+}
+''');
+    _assertReplacementForChildren<ForEachPartsWithDeclaration>(
+      destination: findNode.forEachPartsWithDeclaration('a in'),
+      source: findNode.forEachPartsWithDeclaration('b in'),
+      childAccessors: [
+        (node) => node.loopVariable,
+        (node) => node.iterable,
+      ],
+    );
+  }
+
+  void test_forEachPartsWithIdentifier() {
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  for (a in []) {}
+  for (b in []) {}
+}
+''');
+    _assertReplacementForChildren<ForEachPartsWithIdentifier>(
+      destination: findNode.forEachPartsWithIdentifier('a in'),
+      source: findNode.forEachPartsWithIdentifier('b in'),
+      childAccessors: [
+        (node) => node.identifier,
+        (node) => node.iterable,
+      ],
+    );
   }
 
   void test_forEachStatement_withIdentifier() {
-    ForStatement node = AstTestFactory.forStatement(
-        AstTestFactory.forEachPartsWithIdentifier(
-            AstTestFactory.identifier3("i"), AstTestFactory.identifier3("l")),
-        AstTestFactory.block());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_forEachStatement_withIdentifier_2());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_forEachStatement_withIdentifier_3());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_forEachStatement_withIdentifier());
-  }
-
-  void test_forEachStatement_withLoopVariable() {
-    ForStatement node = AstTestFactory.forStatement(
-        AstTestFactory.forEachPartsWithDeclaration(
-            AstTestFactory.declaredIdentifier3("e"),
-            AstTestFactory.identifier3("l")),
-        AstTestFactory.block());
-    _assertReplace(node,
-        Getter_NodeReplacerTest_test_forEachStatement_withLoopVariable_2());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_forEachStatement_withLoopVariable());
-    _assertReplace(node,
-        Getter_NodeReplacerTest_test_forEachStatement_withLoopVariable_3());
+    var findNode = _parseStringToFindNode(r'''
+void f(int a) {
+  for (a in []) {}
+  for (b in []) {}
+}
+''');
+    _assertReplacementForChildren<ForStatement>(
+      destination: findNode.forStatement('a in'),
+      source: findNode.forStatement('b in'),
+      childAccessors: [
+        (node) => node.body,
+        (node) => node.forLoopParts,
+      ],
+    );
   }
 
   void test_formalParameterList() {
-    FormalParameterList node = AstTestFactory.formalParameterList(
-        [AstTestFactory.simpleFormalParameter3("p")]);
-    _assertReplace(
-        node, ListGetter_NodeReplacerTest_test_formalParameterList(0));
+    var findNode = _parseStringToFindNode(r'''
+void f(int a, int b) {}
+''');
+    _assertReplaceInList(
+      destination: findNode.formalParameterList('int a'),
+      child: findNode.simpleFormalParameter('int a'),
+      replacement: findNode.simpleFormalParameter('int b'),
+    );
   }
 
-  void test_forStatement_withInitialization() {
-    ForStatement node = AstTestFactory.forStatement(
-        AstTestFactory.forPartsWithExpression(AstTestFactory.identifier3("a"),
-            AstTestFactory.booleanLiteral(true), [AstTestFactory.integer(0)]),
-        AstTestFactory.block());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_forStatement_withInitialization_3());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_forStatement_withInitialization_2());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_forStatement_withInitialization());
-    _assertReplace(node,
-        ListGetter_NodeReplacerTest_test_forStatement_withInitialization(0));
+  void test_forPartsWithDeclarations() {
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  for (int i = 0; i < 8; i++, i += 2) {}
+  for (int j = 0; j < 8; j++) {}
+}
+''');
+    var for_i = findNode.forPartsWithDeclarations('i = 0');
+    _assertReplaceInList(
+      destination: for_i,
+      child: for_i.updaters[0],
+      replacement: for_i.updaters[1],
+    );
+    _assertReplacementForChildren<ForPartsWithDeclarations>(
+      destination: for_i,
+      source: findNode.forPartsWithDeclarations('j = 0'),
+      childAccessors: [
+        (node) => node.variables,
+        (node) => node.condition!,
+      ],
+    );
   }
 
-  void test_forStatement_withVariables() {
-    ForStatement node = AstTestFactory.forStatement(
-        AstTestFactory.forPartsWithDeclarations(
-            AstTestFactory.variableDeclarationList2(
-                null, [AstTestFactory.variableDeclaration("i")]),
-            AstTestFactory.booleanLiteral(true),
-            [AstTestFactory.integer(0)]),
-        AstTestFactory.block());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_forStatement_withVariables_2());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_forStatement_withVariables_3());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_forStatement_withVariables());
-    _assertReplace(
-        node, ListGetter_NodeReplacerTest_test_forStatement_withVariables(0));
+  void test_forPartsWithExpression() {
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  for (i = 0; i < 8; i++, i += 2) {}
+  for (j = 0; j < 8; j++) {}
+}
+''');
+    var for_i = findNode.forPartsWithExpression('i = 0');
+    _assertReplaceInList(
+      destination: for_i,
+      child: for_i.updaters[0],
+      replacement: for_i.updaters[1],
+    );
+    _assertReplacementForChildren<ForPartsWithExpression>(
+      destination: for_i,
+      source: findNode.forPartsWithExpression('j = 0'),
+      childAccessors: [
+        (node) => node.initialization!,
+        (node) => node.condition!,
+      ],
+    );
   }
 
   void test_functionDeclaration() {
-    var node = AstTestFactory.functionDeclaration(
-        AstTestFactory.namedType4("R"),
-        null,
-        "f",
-        AstTestFactory.functionExpression2(AstTestFactory.formalParameterList(),
-            AstTestFactory.blockFunctionBody(AstTestFactory.block())));
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    _assertReplace(node, Getter_NodeReplacerTest_test_functionDeclaration());
-    _assertReplace(node, Getter_NodeReplacerTest_test_functionDeclaration_3());
-    _assertReplace(node, Getter_NodeReplacerTest_test_functionDeclaration_2());
-    _testAnnotatedNode(node);
+    var findNode = _parseStringToFindNode(r'''
+@myA1
+@myA2
+int f() => 0;
+double g() => 0;
+''');
+    _assertAnnotatedNode(
+      findNode.functionDeclaration('f()'),
+    );
+    _assertReplacementForChildren<FunctionDeclaration>(
+      destination: findNode.functionDeclaration('f()'),
+      source: findNode.functionDeclaration('g()'),
+      childAccessors: [
+        (node) => node.functionExpression,
+        (node) => node.name,
+        (node) => node.returnType!,
+      ],
+    );
   }
 
   void test_functionDeclarationStatement() {
-    FunctionDeclarationStatement node =
-        AstTestFactory.functionDeclarationStatement(
-            AstTestFactory.namedType4("R"),
-            null,
-            "f",
-            AstTestFactory.functionExpression2(
-                AstTestFactory.formalParameterList(),
-                AstTestFactory.blockFunctionBody(AstTestFactory.block())));
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_functionDeclarationStatement());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  void g() {}
+  void h() {}
+}
+''');
+    _assertReplacementForChildren<FunctionDeclarationStatement>(
+      destination: findNode.functionDeclarationStatement('g()'),
+      source: findNode.functionDeclarationStatement('h()'),
+      childAccessors: [
+        (node) => node.functionDeclaration,
+      ],
+    );
   }
 
   void test_functionExpression() {
-    FunctionExpression node = AstTestFactory.functionExpression2(
-        AstTestFactory.formalParameterList(),
-        AstTestFactory.blockFunctionBody(AstTestFactory.block()));
-    _assertReplace(node, Getter_NodeReplacerTest_test_functionExpression());
-    _assertReplace(node, Getter_NodeReplacerTest_test_functionExpression_2());
+    var findNode = _parseStringToFindNode(r'''
+void f<T>(int a) {
+  0;
+}
+void g<U>(double b) {
+  1;
+}
+''');
+    _assertReplacementForChildren<FunctionExpression>(
+      destination: findNode.functionExpression('<T>'),
+      source: findNode.functionExpression('<U>'),
+      childAccessors: [
+        (node) => node.body,
+        (node) => node.parameters!,
+        (node) => node.typeParameters!,
+      ],
+    );
   }
 
   void test_functionExpressionInvocation() {
-    FunctionExpressionInvocation node =
-        AstTestFactory.functionExpressionInvocation(
-            AstTestFactory.identifier3("f"), [AstTestFactory.integer(0)]);
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_functionExpressionInvocation());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_functionExpressionInvocation_2());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  (g)<int>(0);
+  (h)<double>(1);
+}
+''');
+    _assertReplacementForChildren<FunctionExpressionInvocation>(
+      destination: findNode.functionExpressionInvocation('<int>'),
+      source: findNode.functionExpressionInvocation('<double>'),
+      childAccessors: [
+        (node) => node.function,
+        (node) => node.typeArguments!,
+        (node) => node.argumentList,
+      ],
+    );
   }
 
   void test_functionTypeAlias() {
-    var node = AstTestFactory.typeAlias(
-        AstTestFactory.namedType4("R"),
-        "F",
-        AstTestFactory.typeParameterList(["E"]),
-        AstTestFactory.formalParameterList());
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    _assertReplace(node, Getter_NodeReplacerTest_test_functionTypeAlias_3());
-    _assertReplace(node, Getter_NodeReplacerTest_test_functionTypeAlias_4());
-    _assertReplace(node, Getter_NodeReplacerTest_test_functionTypeAlias());
-    _assertReplace(node, Getter_NodeReplacerTest_test_functionTypeAlias_2());
-    _testAnnotatedNode(node);
+    var findNode = _parseStringToFindNode(r'''
+@myA1
+@myA2
+typedef int F<T>(int a);
+typedef double G<U>(double b);
+''');
+    _assertAnnotatedNode(
+      findNode.functionTypeAlias('int F'),
+    );
+    _assertReplacementForChildren<FunctionTypeAlias>(
+      destination: findNode.functionTypeAlias('int F'),
+      source: findNode.functionTypeAlias('double G'),
+      childAccessors: [
+        (node) => node.name,
+        (node) => node.parameters,
+        (node) => node.returnType!,
+        (node) => node.typeParameters!,
+      ],
+    );
   }
 
   void test_functionTypedFormalParameter() {
-    var node = AstTestFactory.functionTypedFormalParameter(
-        AstTestFactory.namedType4("R"),
-        "f",
-        [AstTestFactory.simpleFormalParameter3("p")]);
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata = [
-      AstTestFactory.annotation(AstTestFactory.identifier3("a"))
-    ];
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_functionTypedFormalParameter());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_functionTypedFormalParameter_2());
-    _testNormalFormalParameter(node);
+    var findNode = _parseStringToFindNode(r'''
+void f(
+  @myA1
+  @myA2
+  int a<T>(int a1),
+  double b<U>(double b2),
+) {}
+''');
+    var a = findNode.functionTypedFormalParameter('a<T>');
+    _assertFormalParameterMetadata(a);
+    _assertReplacementForChildren<FunctionTypedFormalParameter>(
+      destination: findNode.functionTypedFormalParameter('a<T>'),
+      source: findNode.functionTypedFormalParameter('b<U>'),
+      childAccessors: [
+        (node) => node.returnType!,
+        (node) => node.identifier,
+        (node) => node.typeParameters!,
+        (node) => node.parameters,
+      ],
+    );
   }
 
   void test_hideCombinator() {
-    HideCombinator node = AstTestFactory.hideCombinator2(["A", "B"]);
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_hideCombinator(0));
+    var findNode = _parseStringToFindNode(r'''
+import '' hide A, B;
+''');
+    var node = findNode.hideCombinator('hide');
+    _assertReplaceInList(
+      destination: node,
+      child: node.hiddenNames[0],
+      replacement: node.hiddenNames[1],
+    );
   }
 
   void test_ifStatement() {
-    IfStatement node = AstTestFactory.ifStatement2(
-        AstTestFactory.booleanLiteral(true),
-        AstTestFactory.block(),
-        AstTestFactory.block());
-    _assertReplace(node, Getter_NodeReplacerTest_test_ifStatement());
-    _assertReplace(node, Getter_NodeReplacerTest_test_ifStatement_3());
-    _assertReplace(node, Getter_NodeReplacerTest_test_ifStatement_2());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  if (true) {
+    0;
+  } else {
+    1;
+  }
+  if (false) {
+    2;
+  } else {
+    3;
+  }
+}
+''');
+    _assertReplacementForChildren<IfStatement>(
+      destination: findNode.ifStatement('true'),
+      source: findNode.ifStatement('false'),
+      childAccessors: [
+        (node) => node.condition,
+        (node) => node.thenStatement,
+        (node) => node.elseStatement!,
+      ],
+    );
   }
 
   void test_implementsClause() {
-    ImplementsClause node = AstTestFactory.implementsClause(
-        [AstTestFactory.namedType4("I"), AstTestFactory.namedType4("J")]);
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_implementsClause(0));
+    var findNode = _parseStringToFindNode(r'''
+class A implements I, J {}
+''');
+    var node = findNode.implementsClause('implements');
+    _assertReplaceInList(
+      destination: node,
+      child: node.interfaces2[0],
+      replacement: node.interfaces2[1],
+    );
   }
 
   void test_importDirective() {
-    var node = AstTestFactory.importDirective3("", "p", [
-      AstTestFactory.showCombinator2(["A"]),
-      AstTestFactory.hideCombinator2(["B"])
-    ]);
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    _assertReplace(node, Getter_NodeReplacerTest_test_importDirective());
-    _testNamespaceDirective(node);
+    var findNode = _parseStringToFindNode(r'''
+@myA1
+@myA2
+import 'a.dart' hide A show B;
+import 'b.dart';
+''');
+    var import_a = findNode.import('a.dart');
+    _assertAnnotatedNode(import_a);
+    _assertReplaceInList(
+      destination: import_a,
+      child: import_a.combinators[0],
+      replacement: import_a.combinators[1],
+    );
+    _assertReplacementForChildren<ImportDirective>(
+      destination: findNode.import('a.dart'),
+      source: findNode.import('b.dart'),
+      childAccessors: [
+        (node) => node.uri,
+      ],
+    );
   }
 
   void test_indexExpression() {
-    IndexExpression node = AstTestFactory.indexExpression(
-      target: AstTestFactory.identifier3("a"),
-      index: AstTestFactory.identifier3("i"),
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  a[0];
+  b[1];
+}
+''');
+    _assertReplacementForChildren<IndexExpression>(
+      destination: findNode.index('[0]'),
+      source: findNode.index('[1]'),
+      childAccessors: [
+        (node) => node.target!,
+        (node) => node.index,
+      ],
     );
-    _assertReplace(node, Getter_NodeReplacerTest_test_indexExpression());
-    _assertReplace(node, Getter_NodeReplacerTest_test_indexExpression_2());
   }
 
   void test_instanceCreationExpression() {
-    InstanceCreationExpression node =
-        AstTestFactory.instanceCreationExpression3(null,
-            AstTestFactory.namedType4("C"), "c", [AstTestFactory.integer(2)]);
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_instanceCreationExpression_2());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_instanceCreationExpression());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  new A(0);
+  new B(1);
+}
+''');
+    _assertReplacementForChildren<InstanceCreationExpression>(
+      destination: findNode.instanceCreation('A('),
+      source: findNode.instanceCreation('B('),
+      childAccessors: [
+        (node) => node.constructorName,
+        (node) => node.argumentList,
+      ],
+    );
   }
 
   void test_interpolationExpression() {
-    InterpolationExpression node = AstTestFactory.interpolationExpression2("x");
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_interpolationExpression());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  '$foo $bar';
+}
+''');
+    _assertReplacementForChildren<InterpolationExpression>(
+      destination: findNode.interpolationExpression('foo'),
+      source: findNode.interpolationExpression('bar'),
+      childAccessors: [
+        (node) => node.expression,
+      ],
+    );
   }
 
   void test_isExpression() {
-    IsExpression node = AstTestFactory.isExpression(
-        AstTestFactory.identifier3("v"), false, AstTestFactory.namedType4("T"));
-    _assertReplace(node, Getter_NodeReplacerTest_test_isExpression());
-    _assertReplace(node, Getter_NodeReplacerTest_test_isExpression_2());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  0 is int;
+  1 is double;
+}
+''');
+    _assertReplacementForChildren<IsExpression>(
+      destination: findNode.isExpression('0 is'),
+      source: findNode.isExpression('1 is'),
+      childAccessors: [
+        (node) => node.expression,
+        (node) => node.type,
+      ],
+    );
   }
 
   void test_label() {
-    Label node = AstTestFactory.label2("l");
-    _assertReplace(node, Getter_NodeReplacerTest_test_label());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  foo: while (true) {}
+  bar: while (true) {}
+}
+''');
+    _assertReplacementForChildren<Label>(
+      destination: findNode.label('foo:'),
+      source: findNode.label('bar'),
+      childAccessors: [
+        (node) => node.label,
+      ],
+    );
   }
 
   void test_labeledStatement() {
-    LabeledStatement node = AstTestFactory.labeledStatement(
-        [AstTestFactory.label2("l")], AstTestFactory.block());
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_labeledStatement(0));
-    _assertReplace(node, Getter_NodeReplacerTest_test_labeledStatement());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  foo: bar: 0;
+  baz: 1;
+}
+''');
+    var foo = findNode.labeledStatement('foo');
+    _assertReplaceInList(
+      destination: foo,
+      child: foo.labels[0],
+      replacement: foo.labels[1],
+    );
+    _assertReplacementForChildren<LabeledStatement>(
+      destination: foo,
+      source: findNode.labeledStatement('baz'),
+      childAccessors: [
+        (node) => node.statement,
+      ],
+    );
   }
 
   void test_libraryDirective() {
-    var node = AstTestFactory.libraryDirective2("lib");
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    _assertReplace(node, Getter_NodeReplacerTest_test_libraryDirective());
-    _testAnnotatedNode(node);
+    var findNode = _parseStringToFindNode(r'''
+@myA1
+@myA2
+library foo;
+''');
+    var node = findNode.libraryDirective;
+    _assertAnnotatedNode(node);
+    _assertReplacementForChildren<LibraryDirective>(
+      destination: node,
+      source: node,
+      childAccessors: [
+        (node) => node.name,
+      ],
+    );
   }
 
   void test_libraryIdentifier() {
-    LibraryIdentifier node = AstTestFactory.libraryIdentifier2(["lib"]);
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_libraryIdentifier(0));
+    var findNode = _parseStringToFindNode(r'''
+library foo.bar;
+''');
+    var node = findNode.libraryIdentifier('foo');
+    _assertReplaceInList(
+      destination: node,
+      child: node.components[0],
+      replacement: node.components[1],
+    );
   }
 
   void test_listLiteral() {
-    ListLiteral node = AstTestFactory.listLiteral2(
-        null,
-        AstTestFactory.typeArgumentList([AstTestFactory.namedType4("E")]),
-        [AstTestFactory.identifier3("e")]);
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_listLiteral(0));
-    _testTypedLiteral(node);
-  }
-
-  void test_mapLiteral() {
-    SetOrMapLiteral node = AstTestFactory.setOrMapLiteral(
-        null,
-        AstTestFactory.typeArgumentList([AstTestFactory.namedType4("E")]),
-        [AstTestFactory.mapLiteralEntry("k", AstTestFactory.identifier3("v"))]);
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_mapLiteral(0));
-    _testTypedLiteral(node);
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  <int>[0, 1];
+  <double>[];
+}
+''');
+    var node = findNode.listLiteral('[0');
+    _assertReplaceInList(
+      destination: node,
+      child: node.elements[0],
+      replacement: node.elements[1],
+    );
+    _assertReplacementForChildren<ListLiteral>(
+      destination: findNode.listLiteral('<int>'),
+      source: findNode.listLiteral('<double>'),
+      childAccessors: [
+        (node) => node.typeArguments!,
+      ],
+    );
   }
 
   void test_mapLiteralEntry() {
-    MapLiteralEntry node =
-        AstTestFactory.mapLiteralEntry("k", AstTestFactory.identifier3("v"));
-    _assertReplace(node, Getter_NodeReplacerTest_test_mapLiteralEntry_2());
-    _assertReplace(node, Getter_NodeReplacerTest_test_mapLiteralEntry());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  <int, int>{0: 1, 2: 3};
+}
+''');
+    _assertReplacementForChildren<MapLiteralEntry>(
+      destination: findNode.mapLiteralEntry('0: 1'),
+      source: findNode.mapLiteralEntry('2: 3'),
+      childAccessors: [
+        (node) => node.key,
+        (node) => node.value,
+      ],
+    );
   }
 
   void test_methodDeclaration() {
-    var node = AstTestFactory.methodDeclaration2(
-        null,
-        AstTestFactory.namedType4("A"),
-        null,
-        null,
-        AstTestFactory.identifier3("m"),
-        AstTestFactory.formalParameterList(),
-        AstTestFactory.blockFunctionBody(AstTestFactory.block()));
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    _assertReplace(node, Getter_NodeReplacerTest_test_methodDeclaration());
-    _assertReplace(node, Getter_NodeReplacerTest_test_methodDeclaration_3());
-    _assertReplace(node, Getter_NodeReplacerTest_test_methodDeclaration_4());
-    _assertReplace(node, Getter_NodeReplacerTest_test_methodDeclaration_2());
-    _testAnnotatedNode(node);
+    var findNode = _parseStringToFindNode(r'''
+class A {
+  @myA1
+  @myA2
+  int foo<T>(int a) {}
+  double bar<U>(double b) {}
+}
+''');
+    var foo = findNode.methodDeclaration('foo');
+    _assertAnnotatedNode(foo);
+    _assertReplacementForChildren<MethodDeclaration>(
+      destination: foo,
+      source: findNode.methodDeclaration('bar'),
+      childAccessors: [
+        (node) => node.returnType!,
+        (node) => node.name,
+        (node) => node.typeParameters!,
+        (node) => node.parameters!,
+        (node) => node.body,
+      ],
+    );
   }
 
   void test_methodInvocation() {
-    MethodInvocation node = AstTestFactory.methodInvocation(
-        AstTestFactory.identifier3("t"), "m", [AstTestFactory.integer(0)]);
-    _assertReplace(node, Getter_NodeReplacerTest_test_methodInvocation_2());
-    _assertReplace(node, Getter_NodeReplacerTest_test_methodInvocation_3());
-    _assertReplace(node, Getter_NodeReplacerTest_test_methodInvocation());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  a.foo<int>(0);
+  b.bar<double>(1);
+}
+''');
+    _assertReplacementForChildren<MethodInvocation>(
+      destination: findNode.methodInvocation('foo'),
+      source: findNode.methodInvocation('bar'),
+      childAccessors: [
+        (node) => node.target!,
+        (node) => node.typeArguments!,
+        (node) => node.argumentList,
+      ],
+    );
   }
 
   void test_namedExpression() {
-    NamedExpression node =
-        AstTestFactory.namedExpression2("l", AstTestFactory.identifier3("v"));
-    _assertReplace(node, Getter_NodeReplacerTest_test_namedExpression());
-    _assertReplace(node, Getter_NodeReplacerTest_test_namedExpression_2());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  g(foo: 0, bar: 1);
+}
+''');
+    _assertReplacementForChildren<NamedExpression>(
+      destination: findNode.namedExpression('foo'),
+      source: findNode.namedExpression('bar'),
+      childAccessors: [
+        (node) => node.name,
+        (node) => node.expression,
+      ],
+    );
   }
 
   void test_nativeClause() {
-    NativeClause node = AstTestFactory.nativeClause("");
-    _assertReplace(node, Getter_NodeReplacerTest_test_nativeClause());
+    var findNode = _parseStringToFindNode(r'''
+class A native 'foo' {}
+class B native 'bar' {}
+''');
+    _assertReplacementForChildren<NativeClause>(
+      destination: findNode.nativeClause('foo'),
+      source: findNode.nativeClause('bar'),
+      childAccessors: [
+        (node) => node.name!,
+      ],
+    );
   }
 
   void test_nativeFunctionBody() {
-    NativeFunctionBody node = AstTestFactory.nativeFunctionBody("m");
-    _assertReplace(node, Getter_NodeReplacerTest_test_nativeFunctionBody());
+    var findNode = _parseStringToFindNode(r'''
+void f() native 'foo';
+void g() native 'bar';
+''');
+    _assertReplacementForChildren<NativeFunctionBody>(
+      destination: findNode.nativeFunctionBody('foo'),
+      source: findNode.nativeFunctionBody('bar'),
+      childAccessors: [
+        (node) => node.stringLiteral!,
+      ],
+    );
   }
 
   void test_parenthesizedExpression() {
-    ParenthesizedExpression node =
-        AstTestFactory.parenthesizedExpression(AstTestFactory.integer(0));
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_parenthesizedExpression());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  (0);
+  (1);
+}
+''');
+    _assertReplacementForChildren<ParenthesizedExpression>(
+      destination: findNode.parenthesized('0'),
+      source: findNode.parenthesized('1'),
+      childAccessors: [
+        (node) => node.expression,
+      ],
+    );
   }
 
   void test_partDirective() {
-    var node = AstTestFactory.partDirective2("");
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    _testUriBasedDirective(node);
+    var findNode = _parseStringToFindNode(r'''
+@myA1
+@myA2
+part 'a.dart';
+part 'b.dart';
+''');
+    var part_a = findNode.part('a.dart');
+    _assertAnnotatedNode(part_a);
+    _assertReplacementForChildren<PartDirective>(
+      destination: findNode.part('a.dart'),
+      source: findNode.part('b.dart'),
+      childAccessors: [
+        (node) => node.uri,
+      ],
+    );
   }
 
   void test_partOfDirective() {
-    var node = AstTestFactory.partOfDirective(
-        AstTestFactory.libraryIdentifier2(["lib"]));
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    _assertReplace(node, Getter_NodeReplacerTest_test_partOfDirective());
-    _testAnnotatedNode(node);
+    var findNode = _parseStringToFindNode(r'''
+@myA1
+@myA2
+part of 'a.dart';
+''');
+    var partOf_a = findNode.partOf('a.dart');
+    _assertAnnotatedNode(partOf_a);
+    _assertReplacementForChildren<PartOfDirective>(
+      destination: findNode.partOf('a.dart'),
+      source: findNode.partOf('a.dart'),
+      childAccessors: [
+        (node) => node.uri!,
+      ],
+    );
   }
 
   void test_postfixExpression() {
-    PostfixExpression node = AstTestFactory.postfixExpression(
-        AstTestFactory.identifier3("x"), TokenType.MINUS_MINUS);
-    _assertReplace(node, Getter_NodeReplacerTest_test_postfixExpression());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  a++;
+  b++;
+}
+''');
+    _assertReplacementForChildren<PostfixExpression>(
+      destination: findNode.postfix('a++'),
+      source: findNode.postfix('b++'),
+      childAccessors: [
+        (node) => node.operand,
+      ],
+    );
   }
 
   void test_prefixedIdentifier() {
-    PrefixedIdentifier node = AstTestFactory.identifier5("a", "b");
-    _assertReplace(node, Getter_NodeReplacerTest_test_prefixedIdentifier_2());
-    _assertReplace(node, Getter_NodeReplacerTest_test_prefixedIdentifier());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  a.foo;
+  b.bar;
+}
+''');
+    _assertReplacementForChildren<PrefixedIdentifier>(
+      destination: findNode.prefixed('a.foo'),
+      source: findNode.prefixed('b.bar'),
+      childAccessors: [
+        (node) => node.prefix,
+        (node) => node.identifier,
+      ],
+    );
   }
 
   void test_prefixExpression() {
-    PrefixExpression node = AstTestFactory.prefixExpression(
-        TokenType.PLUS_PLUS, AstTestFactory.identifier3("y"));
-    _assertReplace(node, Getter_NodeReplacerTest_test_prefixExpression());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  ++a;
+  ++b;
+}
+''');
+    _assertReplacementForChildren<PrefixExpression>(
+      destination: findNode.prefix('++a'),
+      source: findNode.prefix('++b'),
+      childAccessors: [
+        (node) => node.operand,
+      ],
+    );
   }
 
   void test_propertyAccess() {
-    PropertyAccess node =
-        AstTestFactory.propertyAccess2(AstTestFactory.identifier3("x"), "y");
-    _assertReplace(node, Getter_NodeReplacerTest_test_propertyAccess());
-    _assertReplace(node, Getter_NodeReplacerTest_test_propertyAccess_2());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  (a).foo;
+  (b).bar;
+}
+''');
+    _assertReplacementForChildren<PropertyAccess>(
+      destination: findNode.propertyAccess('(a)'),
+      source: findNode.propertyAccess('(b)'),
+      childAccessors: [
+        (node) => node.target!,
+        (node) => node.propertyName,
+      ],
+    );
   }
 
   void test_redirectingConstructorInvocation() {
-    RedirectingConstructorInvocation node =
-        AstTestFactory.redirectingConstructorInvocation2(
-            "c", [AstTestFactory.integer(0)]);
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_redirectingConstructorInvocation());
-    _assertReplace(node,
-        Getter_NodeReplacerTest_test_redirectingConstructorInvocation_2());
+    var findNode = _parseStringToFindNode(r'''
+class A {
+  A.named();
+  A.foo() : this.named(0);
+  A.bar() : this.named(1);
+}
+''');
+    _assertReplacementForChildren<RedirectingConstructorInvocation>(
+      destination: findNode.redirectingConstructorInvocation('(0)'),
+      source: findNode.redirectingConstructorInvocation('(1)'),
+      childAccessors: [
+        (node) => node.constructorName!,
+        (node) => node.argumentList,
+      ],
+    );
   }
 
   void test_returnStatement() {
-    ReturnStatement node =
-        AstTestFactory.returnStatement2(AstTestFactory.integer(0));
-    _assertReplace(node, Getter_NodeReplacerTest_test_returnStatement());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  return 0;
+  return 1;
+}
+''');
+    _assertReplacementForChildren<ReturnStatement>(
+      destination: findNode.returnStatement('0;'),
+      source: findNode.returnStatement('1;'),
+      childAccessors: [
+        (node) => node.expression!,
+      ],
+    );
+  }
+
+  void test_setOrMapLiteral() {
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  <int, int>{0: 1, 2: 3};
+  <double, double>{};
+}
+''');
+    var node = findNode.setOrMapLiteral('<int');
+    _assertReplaceInList(
+      destination: node,
+      child: node.elements[0],
+      replacement: node.elements[1],
+    );
+    _assertReplacementForChildren<SetOrMapLiteral>(
+      destination: findNode.setOrMapLiteral('<int'),
+      source: findNode.setOrMapLiteral('<double'),
+      childAccessors: [
+        (node) => node.typeArguments!,
+      ],
+    );
   }
 
   void test_showCombinator() {
-    ShowCombinator node = AstTestFactory.showCombinator2(["X", "Y"]);
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_showCombinator(0));
+    var findNode = _parseStringToFindNode(r'''
+import '' show A, B;
+''');
+    var node = findNode.showCombinator('show');
+    _assertReplaceInList(
+      destination: node,
+      child: node.shownNames[0],
+      replacement: node.shownNames[1],
+    );
   }
 
   void test_simpleFormalParameter() {
-    var node = AstTestFactory.simpleFormalParameter4(
-        AstTestFactory.namedType4("T"), "p");
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata = [
-      AstTestFactory.annotation(AstTestFactory.identifier3("a"))
-    ];
-    _assertReplace(node, Getter_NodeReplacerTest_test_simpleFormalParameter());
-    _testNormalFormalParameter(node);
+    var findNode = _parseStringToFindNode(r'''
+void f(
+  @myA1
+  @myA2
+  int a,
+  int b
+) {}
+''');
+    var a = findNode.simpleFormalParameter('int a');
+    _assertFormalParameterMetadata(a);
+    _assertReplacementForChildren<SimpleFormalParameter>(
+      destination: a,
+      source: findNode.simpleFormalParameter('int b'),
+      childAccessors: [
+        (node) => node.type!,
+        (node) => node.identifier!,
+      ],
+    );
   }
 
   void test_stringInterpolation() {
-    var unit = parseString(content: 'var v = "first \$x last";').unit;
-    var declaration = unit.declarations[0] as TopLevelVariableDeclaration;
-    var variable = declaration.variables.variables[0];
-    var node = variable.initializer as StringInterpolation;
-    _assertReplace(
-        node, ListGetter_NodeReplacerTest_test_stringInterpolation(0));
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  'my $foo other $bar';
+}
+''');
+    var node = findNode.stringInterpolation('foo');
+    _assertReplaceInList(
+      destination: node,
+      child: node.elements[0],
+      replacement: node.elements[1],
+    );
   }
 
   void test_superConstructorInvocation() {
-    SuperConstructorInvocation node =
-        AstTestFactory.superConstructorInvocation2(
-            "s", [AstTestFactory.integer(1)]);
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_superConstructorInvocation());
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_superConstructorInvocation_2());
+    var findNode = _parseStringToFindNode(r'''
+class A {
+  A.foo() : super.first(0);
+  A.bar() : super.second(0);
+}
+''');
+    _assertReplacementForChildren<SuperConstructorInvocation>(
+      destination: findNode.superConstructorInvocation('first'),
+      source: findNode.superConstructorInvocation('second'),
+      childAccessors: [
+        (node) => node.constructorName!,
+        (node) => node.argumentList,
+      ],
+    );
+  }
+
+  @FailingTest(issue: 'https://github.com/dart-lang/sdk/issues/47951')
+  void test_superFormalParameter() {
+    var findNode = _parseStringToFindNode(r'''
+class A {
+  A(num a);
+}
+
+class B extends A {
+  B.sub1(int super.a1);
+  B.sub2(double super.a2);
+}
+''');
+    _assertReplacementForChildren<SuperFormalParameter>(
+      destination: findNode.superFormalParameter('a1'),
+      source: findNode.superFormalParameter('a2'),
+      childAccessors: [
+        (node) => node.type!,
+        (node) => node.identifier,
+      ],
+    );
   }
 
   @FailingTest(issue: 'https://github.com/dart-lang/sdk/issues/47741')
-  void test_superFormalParameter() {
+  void test_superFormalParameter_functionTyped() {
     var findNode = _parseStringToFindNode(r'''
 class A {
   A(int foo<T>(int a));
@@ -2132,10 +1678,10 @@
   B.sub2(double super.bar2<T2>(int a2),);
 }
 ''');
-    _assertReplace2<SuperFormalParameter>(
+    _assertReplacementForChildren<SuperFormalParameter>(
       destination: findNode.superFormalParameter('bar1'),
       source: findNode.superFormalParameter('bar2'),
-      getters: [
+      childAccessors: [
         (node) => node.type!,
         (node) => node.identifier,
         (node) => node.typeParameters!,
@@ -2145,230 +1691,368 @@
   }
 
   void test_switchCase() {
-    SwitchCase node = AstTestFactory.switchCase2([AstTestFactory.label2("l")],
-        AstTestFactory.integer(0), [AstTestFactory.block()]);
-    _assertReplace(node, Getter_NodeReplacerTest_test_switchCase());
-    _testSwitchMember(node);
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  switch (x) {
+    foo: bar:
+    case 0: 0; 1;
+    case 1: break;
+  }
+}
+''');
+    _assertSwitchMember(
+      findNode.switchCase('case 0'),
+    );
+    _assertReplacementForChildren<SwitchCase>(
+      destination: findNode.switchCase('case 0'),
+      source: findNode.switchCase('case 1'),
+      childAccessors: [
+        (node) => node.expression,
+      ],
+    );
   }
 
   void test_switchDefault() {
-    SwitchDefault node = AstTestFactory.switchDefault(
-        [AstTestFactory.label2("l")], [AstTestFactory.block()]);
-    _testSwitchMember(node);
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  switch (x) {
+    foo: bar:
+    default: 0; 1;
+  }
+}
+''');
+    _assertSwitchMember(
+      findNode.switchDefault('default: 0'),
+    );
   }
 
   void test_switchStatement() {
-    SwitchStatement node =
-        AstTestFactory.switchStatement(AstTestFactory.identifier3("x"), [
-      AstTestFactory.switchCase2([AstTestFactory.label2("l")],
-          AstTestFactory.integer(0), [AstTestFactory.block()]),
-      AstTestFactory.switchDefault(
-          [AstTestFactory.label2("l")], [AstTestFactory.block()])
-    ]);
-    _assertReplace(node, Getter_NodeReplacerTest_test_switchStatement());
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_switchStatement(0));
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  switch (0) {
+    case 0: break;
+    case 1: break;
+  }
+  switch (1) {}
+}
+''');
+    _assertReplaceInList(
+      destination: findNode.switchStatement('(0)'),
+      child: findNode.switchCase('case 0'),
+      replacement: findNode.switchCase('case 1'),
+    );
+    _assertReplacementForChildren<SwitchStatement>(
+      destination: findNode.switchStatement('(0)'),
+      source: findNode.switchStatement('(1)'),
+      childAccessors: [
+        (node) => node.expression,
+      ],
+    );
   }
 
   void test_throwExpression() {
-    ThrowExpression node =
-        AstTestFactory.throwExpression2(AstTestFactory.identifier3("e"));
-    _assertReplace(node, Getter_NodeReplacerTest_test_throwExpression());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  throw 0;
+  throw 1;
+}
+''');
+    _assertReplacementForChildren<ThrowExpression>(
+      destination: findNode.throw_('throw 0'),
+      source: findNode.throw_('throw 1'),
+      childAccessors: [
+        (node) => node.expression,
+      ],
+    );
   }
 
   void test_topLevelVariableDeclaration() {
-    var node = AstTestFactory.topLevelVariableDeclaration(
-        null,
-        AstTestFactory.namedType4("T"),
-        [AstTestFactory.variableDeclaration("t")]);
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_topLevelVariableDeclaration());
-    _testAnnotatedNode(node);
+    var findNode = _parseStringToFindNode(r'''
+@myA1
+@myA2
+var a = 0;
+var b = 1;
+''');
+    _assertAnnotatedNode(
+      findNode.topLevelVariableDeclaration('a = 0'),
+    );
+    _assertReplacementForChildren<TopLevelVariableDeclaration>(
+      destination: findNode.topLevelVariableDeclaration('a = 0'),
+      source: findNode.topLevelVariableDeclaration('b = 1'),
+      childAccessors: [
+        (node) => node.variables,
+      ],
+    );
   }
 
   void test_tryStatement() {
-    TryStatement node = AstTestFactory.tryStatement3(
-        AstTestFactory.block(),
-        [
-          AstTestFactory.catchClause("e", [AstTestFactory.block()])
-        ],
-        AstTestFactory.block());
-    _assertReplace(node, Getter_NodeReplacerTest_test_tryStatement_2());
-    _assertReplace(node, Getter_NodeReplacerTest_test_tryStatement());
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_tryStatement(0));
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  try { // 0
+    0;
+  } on E1 {
+  } on E2 {
+  } finally {
+    1;
+  }
+  try { // 1
+    2;
+  } finally {
+    3;
+  }
+}
+''');
+    _assertReplaceInList(
+      destination: findNode.tryStatement('// 0'),
+      child: findNode.catchClause('E1'),
+      replacement: findNode.catchClause('E2'),
+    );
+    _assertReplacementForChildren<TryStatement>(
+      destination: findNode.tryStatement('// 0'),
+      source: findNode.tryStatement('// 1'),
+      childAccessors: [
+        (node) => node.body,
+        (node) => node.finallyBlock!,
+      ],
+    );
   }
 
   void test_typeArgumentList() {
-    TypeArgumentList node =
-        AstTestFactory.typeArgumentList2([AstTestFactory.namedType4("A")]);
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_typeArgumentList(0));
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  g<int, double>();
+}
+''');
+    _assertReplaceInList(
+      destination: findNode.typeArgumentList('<int'),
+      child: findNode.namedType('int'),
+      replacement: findNode.namedType('double'),
+    );
   }
 
   void test_typeName() {
-    NamedType node = AstTestFactory.namedType4(
-        "T", [AstTestFactory.namedType4("E"), AstTestFactory.namedType4("F")]);
-    _assertReplace(node, Getter_NodeReplacerTest_test_typeName_2());
-    _assertReplace(node, Getter_NodeReplacerTest_test_typeName());
+    var findNode = _parseStringToFindNode(r'''
+void f(List<int> a, Set<double> b) {}
+''');
+    _assertReplacementForChildren<NamedType>(
+      destination: findNode.namedType('List<int>'),
+      source: findNode.namedType('Set<double>'),
+      childAccessors: [
+        (node) => node.name,
+        (node) => node.typeArguments!,
+      ],
+    );
   }
 
   void test_typeParameter() {
-    TypeParameter node =
-        AstTestFactory.typeParameter2("E", AstTestFactory.namedType4("B"));
-    _assertReplace(node, Getter_NodeReplacerTest_test_typeParameter_2());
-    _assertReplace(node, Getter_NodeReplacerTest_test_typeParameter());
+    var findNode = _parseStringToFindNode(r'''
+class A<T extends int, U extends double> {}
+''');
+    _assertReplacementForChildren<TypeParameter>(
+      destination: findNode.typeParameter('T extends'),
+      source: findNode.typeParameter('U extends'),
+      childAccessors: [
+        (node) => node.name,
+        (node) => node.bound!,
+      ],
+    );
   }
 
   void test_typeParameterList() {
-    TypeParameterList node = AstTestFactory.typeParameterList2(["A", "B"]);
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_typeParameterList(0));
+    var findNode = _parseStringToFindNode(r'''
+class A<T, U> {}
+''');
+    var node = findNode.typeParameterList('<T, U>');
+    _assertReplaceInList(
+      destination: node,
+      child: node.typeParameters[0],
+      replacement: node.typeParameters[1],
+    );
   }
 
   void test_variableDeclaration() {
-    var node =
-        AstTestFactory.variableDeclaration2("a", AstTestFactory.nullLiteral());
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    _assertReplace(node, Getter_NodeReplacerTest_test_variableDeclaration());
-    _assertReplace(node, Getter_NodeReplacerTest_test_variableDeclaration_2());
-    _testAnnotatedNode(node);
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  var a = 0;
+  var b = 1;
+}
+''');
+    _assertReplacementForChildren<VariableDeclaration>(
+      destination: findNode.variableDeclaration('a = 0'),
+      source: findNode.variableDeclaration('b = 1'),
+      childAccessors: [
+        (node) => node.name,
+        (node) => node.initializer!,
+      ],
+    );
   }
 
   void test_variableDeclarationList() {
-    var node = AstTestFactory.variableDeclarationList(
-        null,
-        AstTestFactory.namedType4("T"),
-        [AstTestFactory.variableDeclaration("a")]);
-    node.documentationComment = astFactory.endOfLineComment(EMPTY_TOKEN_LIST);
-    node.metadata
-        .add(AstTestFactory.annotation(AstTestFactory.identifier3("a")));
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_variableDeclarationList());
-    _assertReplace(
-        node, ListGetter_NodeReplacerTest_test_variableDeclarationList(0));
-    _testAnnotatedNode(node);
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  int a = 0, b = 1;
+  double c = 2;
+}
+''');
+    _assertReplaceInList(
+      destination: findNode.variableDeclarationList('int a'),
+      child: findNode.variableDeclaration('a = 0'),
+      replacement: findNode.variableDeclaration('b = 1'),
+    );
+    _assertReplacementForChildren<VariableDeclarationList>(
+      destination: findNode.variableDeclarationList('int a'),
+      source: findNode.variableDeclarationList('double c'),
+      childAccessors: [
+        (node) => node.type!,
+      ],
+    );
   }
 
   void test_variableDeclarationStatement() {
-    VariableDeclarationStatement node =
-        AstTestFactory.variableDeclarationStatement(
-            null,
-            AstTestFactory.namedType4("T"),
-            [AstTestFactory.variableDeclaration("a")]);
-    _assertReplace(
-        node, Getter_NodeReplacerTest_test_variableDeclarationStatement());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  int a = 0;
+  double b = 1;
+}
+''');
+    _assertReplacementForChildren<VariableDeclarationStatement>(
+      destination: findNode.variableDeclarationStatement('int a'),
+      source: findNode.variableDeclarationStatement('double b'),
+      childAccessors: [
+        (node) => node.variables,
+      ],
+    );
   }
 
   void test_whileStatement() {
-    WhileStatement node = AstTestFactory.whileStatement(
-        AstTestFactory.booleanLiteral(true), AstTestFactory.block());
-    _assertReplace(node, Getter_NodeReplacerTest_test_whileStatement());
-    _assertReplace(node, Getter_NodeReplacerTest_test_whileStatement_2());
+    var findNode = _parseStringToFindNode(r'''
+void f() {
+  while (true) {
+    0;
+  }
+  while (false) {
+    1;
+  }
+}
+''');
+    _assertReplacementForChildren<WhileStatement>(
+      destination: findNode.whileStatement('(true)'),
+      source: findNode.whileStatement('(false)'),
+      childAccessors: [
+        (node) => node.condition,
+        (node) => node.body,
+      ],
+    );
   }
 
   void test_withClause() {
-    WithClause node =
-        AstTestFactory.withClause([AstTestFactory.namedType4("M")]);
-    _assertReplace(node, ListGetter_NodeReplacerTest_test_withClause(0));
+    var findNode = _parseStringToFindNode(r'''
+class A with M, N {}
+''');
+    var node = findNode.withClause('with');
+    _assertReplaceInList(
+      destination: node,
+      child: node.mixinTypes2[0],
+      replacement: node.mixinTypes2[1],
+    );
   }
 
   void test_yieldStatement() {
-    var node = AstTestFactory.yieldStatement(AstTestFactory.identifier3("A"));
-    _assertReplace(node, Getter_NodeReplacerTest_test_yieldStatement());
+    var findNode = _parseStringToFindNode(r'''
+void f() sync* {
+  yield 0;
+  yield 1;
+}
+''');
+    _assertReplacementForChildren<YieldStatement>(
+      destination: findNode.yieldStatement('yield 0;'),
+      source: findNode.yieldStatement('yield 1'),
+      childAccessors: [
+        (node) => node.expression,
+      ],
+    );
   }
 
-  void _assertReplace(AstNode parent, NodeReplacerTest_Getter getter) {
-    var child = getter.get(parent);
-    if (child != null) {
-      NodeReplacer.replace(child, child);
-      expect(getter.get(parent), child);
-      expect(child.parent, child.parent);
-    }
+  /// Asserts that the first annotation can be replaced with the second.
+  /// Expects that [node] has at least 2 annotations.
+  void _assertAnnotatedNode(AnnotatedNode node) {
+    _assertReplaceInList(
+      destination: node,
+      child: node.metadata[0],
+      replacement: node.metadata[1],
+    );
   }
 
-  void _assertReplace2<T extends AstNode>({
+  /// Asserts that the first annotation can be replaced with the second.
+  /// Expects that [node] has at least 2 annotations.
+  void _assertFormalParameterMetadata(FormalParameter node) {
+    _assertReplaceInList(
+      destination: node,
+      child: node.metadata[0],
+      replacement: node.metadata[1],
+    );
+  }
+
+  /// Asserts that a [child] node, with parent that is [destination], can
+  /// by replaced with the [replacement], and then its parent is [destination].
+  void _assertReplaceInList({
+    required AstNode destination,
+    required AstNode child,
+    required AstNode replacement,
+  }) {
+    expect(child.parent, destination);
+
+    NodeReplacer.replace(child, replacement);
+    expect(replacement.parent, destination);
+  }
+
+  /// Asserts for each child returned by a function from [childAccessors]
+  /// for [destination] that its parent is actually [destination], and then
+  /// replaces it with a node returned this function for [source]. At the end,
+  /// checks that the function, invoked for [destination] now returns the
+  /// replacement node, and its parent is now [destination].
+  void _assertReplacementForChildren<T extends AstNode>({
     required T destination,
     required T source,
-    required List<AstNode Function(T node)> getters,
+    required List<AstNode Function(T node)> childAccessors,
   }) {
-    for (var getter in getters) {
-      var child = getter(destination);
+    for (var childAccessor in childAccessors) {
+      var child = childAccessor(destination);
       expect(child.parent, destination);
 
-      var replacement = getter(source);
+      var replacement = childAccessor(source);
       NodeReplacer.replace(child, replacement);
-      expect(getter(destination), replacement);
+      expect(childAccessor(destination), replacement);
       expect(replacement.parent, destination);
     }
   }
 
+  void _assertSwitchMember(SwitchMember node) {
+    _assertReplaceInList(
+      destination: node,
+      child: node.labels[0],
+      replacement: node.labels[1],
+    );
+    _assertReplaceInList(
+      destination: node,
+      child: node.statements[0],
+      replacement: node.statements[1],
+    );
+  }
+
   FindNode _parseStringToFindNode(String content) {
     var parseResult = parseString(
       content: content,
       featureSet: FeatureSet.fromEnableFlags2(
         sdkLanguageVersion: ExperimentStatus.currentVersion,
         flags: [
+          Feature.enhanced_enums.enableString,
           Feature.super_parameters.enableString,
         ],
       ),
     );
     return FindNode(parseResult.content, parseResult.unit);
   }
-
-  void _testAnnotatedNode(AnnotatedNode node) {
-    _assertReplace(node, Getter_NodeReplacerTest_testAnnotatedNode());
-    _assertReplace(node, ListGetter_NodeReplacerTest_testAnnotatedNode(0));
-  }
-
-  void _testNamespaceDirective(NamespaceDirective node) {
-    _assertReplace(node, ListGetter_NodeReplacerTest_testNamespaceDirective(0));
-    _testUriBasedDirective(node);
-  }
-
-  void _testNormalFormalParameter(NormalFormalParameter node) {
-    _assertReplace(node, Getter_NodeReplacerTest_testNormalFormalParameter_2());
-    _assertReplace(node, Getter_NodeReplacerTest_testNormalFormalParameter());
-    _assertReplace(
-        node, ListGetter_NodeReplacerTest_testNormalFormalParameter(0));
-  }
-
-  void _testSwitchMember(SwitchMember node) {
-    _assertReplace(node, ListGetter_NodeReplacerTest_testSwitchMember(0));
-    _assertReplace(node, ListGetter_NodeReplacerTest_testSwitchMember_2(0));
-  }
-
-  void _testTypedLiteral(TypedLiteral node) {
-    _assertReplace(node, Getter_NodeReplacerTest_testTypedLiteral());
-  }
-
-  void _testUriBasedDirective(UriBasedDirective node) {
-    _assertReplace(node, Getter_NodeReplacerTest_testUriBasedDirective());
-    _testAnnotatedNode(node);
-  }
-}
-
-abstract class NodeReplacerTest_Getter<P, C extends AstNode> {
-  C? get(P parent);
-}
-
-abstract class NodeReplacerTest_ListGetter<P extends AstNode, C extends AstNode>
-    implements NodeReplacerTest_Getter<P, C> {
-  final int _index;
-
-  NodeReplacerTest_ListGetter(this._index);
-
-  @override
-  C? get(P parent) {
-    NodeList<C> list = getList(parent);
-    if (list.isEmpty) {
-      return null;
-    }
-    return list[_index];
-  }
-
-  NodeList<C> getList(P parent);
 }
 
 @reflectiveTest
@@ -2516,254 +2200,3 @@
     expect(r.toString(), "[offset=10, length=1]");
   }
 }
-
-@reflectiveTest
-class StringUtilitiesTest {
-  void test_computeLineStarts_n() {
-    List<int> starts = StringUtilities.computeLineStarts('a\nbb\nccc');
-    expect(starts, <int>[0, 2, 5]);
-  }
-
-  void test_computeLineStarts_r() {
-    List<int> starts = StringUtilities.computeLineStarts('a\rbb\rccc');
-    expect(starts, <int>[0, 2, 5]);
-  }
-
-  void test_computeLineStarts_rn() {
-    List<int> starts = StringUtilities.computeLineStarts('a\r\nbb\r\nccc');
-    expect(starts, <int>[0, 3, 7]);
-  }
-
-  void test_EMPTY() {
-    expect(StringUtilities.EMPTY, "");
-    expect(StringUtilities.EMPTY.isEmpty, isTrue);
-  }
-
-  void test_EMPTY_ARRAY() {
-    expect(StringUtilities.EMPTY_ARRAY.length, 0);
-  }
-
-  void test_endsWith3() {
-    expect(StringUtilities.endsWith3("abc", 0x61, 0x62, 0x63), isTrue);
-    expect(StringUtilities.endsWith3("abcdefghi", 0x67, 0x68, 0x69), isTrue);
-    expect(StringUtilities.endsWith3("abcdefghi", 0x64, 0x65, 0x61), isFalse);
-    // missing
-  }
-
-  void test_endsWithChar() {
-    expect(StringUtilities.endsWithChar("a", 0x61), isTrue);
-    expect(StringUtilities.endsWithChar("b", 0x61), isFalse);
-    expect(StringUtilities.endsWithChar("", 0x61), isFalse);
-  }
-
-  void test_indexOf1() {
-    expect(StringUtilities.indexOf1("a", 0, 0x61), 0);
-    expect(StringUtilities.indexOf1("abcdef", 0, 0x61), 0);
-    expect(StringUtilities.indexOf1("abcdef", 0, 0x63), 2);
-    expect(StringUtilities.indexOf1("abcdef", 0, 0x66), 5);
-    expect(StringUtilities.indexOf1("abcdef", 0, 0x7A), -1);
-    expect(StringUtilities.indexOf1("abcdef", 1, 0x61), -1);
-    // before start
-  }
-
-  void test_indexOf2() {
-    expect(StringUtilities.indexOf2("ab", 0, 0x61, 0x62), 0);
-    expect(StringUtilities.indexOf2("abcdef", 0, 0x61, 0x62), 0);
-    expect(StringUtilities.indexOf2("abcdef", 0, 0x63, 0x64), 2);
-    expect(StringUtilities.indexOf2("abcdef", 0, 0x65, 0x66), 4);
-    expect(StringUtilities.indexOf2("abcdef", 0, 0x64, 0x61), -1);
-    expect(StringUtilities.indexOf2("abcdef", 1, 0x61, 0x62), -1);
-    // before start
-  }
-
-  void test_indexOf4() {
-    expect(StringUtilities.indexOf4("abcd", 0, 0x61, 0x62, 0x63, 0x64), 0);
-    expect(StringUtilities.indexOf4("abcdefghi", 0, 0x61, 0x62, 0x63, 0x64), 0);
-    expect(StringUtilities.indexOf4("abcdefghi", 0, 0x63, 0x64, 0x65, 0x66), 2);
-    expect(StringUtilities.indexOf4("abcdefghi", 0, 0x66, 0x67, 0x68, 0x69), 5);
-    expect(
-        StringUtilities.indexOf4("abcdefghi", 0, 0x64, 0x65, 0x61, 0x64), -1);
-    expect(
-        StringUtilities.indexOf4("abcdefghi", 1, 0x61, 0x62, 0x63, 0x64), -1);
-    // before start
-  }
-
-  void test_indexOf5() {
-    expect(
-        StringUtilities.indexOf5("abcde", 0, 0x61, 0x62, 0x63, 0x64, 0x65), 0);
-    expect(
-        StringUtilities.indexOf5("abcdefghi", 0, 0x61, 0x62, 0x63, 0x64, 0x65),
-        0);
-    expect(
-        StringUtilities.indexOf5("abcdefghi", 0, 0x63, 0x64, 0x65, 0x66, 0x67),
-        2);
-    expect(
-        StringUtilities.indexOf5("abcdefghi", 0, 0x65, 0x66, 0x67, 0x68, 0x69),
-        4);
-    expect(
-        StringUtilities.indexOf5("abcdefghi", 0, 0x64, 0x65, 0x66, 0x69, 0x6E),
-        -1);
-    expect(
-        StringUtilities.indexOf5("abcdefghi", 1, 0x61, 0x62, 0x63, 0x64, 0x65),
-        -1);
-    // before start
-  }
-
-  void test_isEmpty() {
-    expect(StringUtilities.isEmpty(""), isTrue);
-    expect(StringUtilities.isEmpty(" "), isFalse);
-    expect(StringUtilities.isEmpty("a"), isFalse);
-    expect(StringUtilities.isEmpty(StringUtilities.EMPTY), isTrue);
-  }
-
-  void test_isTagName() {
-    expect(StringUtilities.isTagName(null), isFalse);
-    expect(StringUtilities.isTagName(""), isFalse);
-    expect(StringUtilities.isTagName("-"), isFalse);
-    expect(StringUtilities.isTagName("0"), isFalse);
-    expect(StringUtilities.isTagName("0a"), isFalse);
-    expect(StringUtilities.isTagName("a b"), isFalse);
-    expect(StringUtilities.isTagName("a0"), isTrue);
-    expect(StringUtilities.isTagName("a"), isTrue);
-    expect(StringUtilities.isTagName("ab"), isTrue);
-    expect(StringUtilities.isTagName("a-b"), isTrue);
-  }
-
-  void test_printListOfQuotedNames_empty() {
-    expect(() {
-      StringUtilities.printListOfQuotedNames([]);
-    }, throwsArgumentError);
-  }
-
-  void test_printListOfQuotedNames_five() {
-    expect(
-        StringUtilities.printListOfQuotedNames(
-            <String>["a", "b", "c", "d", "e"]),
-        "'a', 'b', 'c', 'd' and 'e'");
-  }
-
-  void test_printListOfQuotedNames_null() {
-    expect(() {
-      StringUtilities.printListOfQuotedNames(null);
-    }, throwsArgumentError);
-  }
-
-  void test_printListOfQuotedNames_one() {
-    expect(() {
-      StringUtilities.printListOfQuotedNames(<String>["a"]);
-    }, throwsArgumentError);
-  }
-
-  void test_printListOfQuotedNames_three() {
-    expect(StringUtilities.printListOfQuotedNames(<String>["a", "b", "c"]),
-        "'a', 'b' and 'c'");
-  }
-
-  void test_printListOfQuotedNames_two() {
-    expect(StringUtilities.printListOfQuotedNames(<String>["a", "b"]),
-        "'a' and 'b'");
-  }
-
-  void test_startsWith2() {
-    expect(StringUtilities.startsWith2("ab", 0, 0x61, 0x62), isTrue);
-    expect(StringUtilities.startsWith2("abcdefghi", 0, 0x61, 0x62), isTrue);
-    expect(StringUtilities.startsWith2("abcdefghi", 2, 0x63, 0x64), isTrue);
-    expect(StringUtilities.startsWith2("abcdefghi", 5, 0x66, 0x67), isTrue);
-    expect(StringUtilities.startsWith2("abcdefghi", 0, 0x64, 0x64), isFalse);
-    // missing
-  }
-
-  void test_startsWith3() {
-    expect(StringUtilities.startsWith3("abc", 0, 0x61, 0x62, 0x63), isTrue);
-    expect(
-        StringUtilities.startsWith3("abcdefghi", 0, 0x61, 0x62, 0x63), isTrue);
-    expect(
-        StringUtilities.startsWith3("abcdefghi", 2, 0x63, 0x64, 0x65), isTrue);
-    expect(
-        StringUtilities.startsWith3("abcdefghi", 6, 0x67, 0x68, 0x69), isTrue);
-    expect(
-        StringUtilities.startsWith3("abcdefghi", 0, 0x64, 0x65, 0x61), isFalse);
-    // missing
-  }
-
-  void test_startsWith4() {
-    expect(
-        StringUtilities.startsWith4("abcd", 0, 0x61, 0x62, 0x63, 0x64), isTrue);
-    expect(StringUtilities.startsWith4("abcdefghi", 0, 0x61, 0x62, 0x63, 0x64),
-        isTrue);
-    expect(StringUtilities.startsWith4("abcdefghi", 2, 0x63, 0x64, 0x65, 0x66),
-        isTrue);
-    expect(StringUtilities.startsWith4("abcdefghi", 5, 0x66, 0x67, 0x68, 0x69),
-        isTrue);
-    expect(StringUtilities.startsWith4("abcdefghi", 0, 0x64, 0x65, 0x61, 0x64),
-        isFalse);
-    // missing
-  }
-
-  void test_startsWith5() {
-    expect(
-        StringUtilities.startsWith5("abcde", 0, 0x61, 0x62, 0x63, 0x64, 0x65),
-        isTrue);
-    expect(
-        StringUtilities.startsWith5(
-            "abcdefghi", 0, 0x61, 0x62, 0x63, 0x64, 0x65),
-        isTrue);
-    expect(
-        StringUtilities.startsWith5(
-            "abcdefghi", 2, 0x63, 0x64, 0x65, 0x66, 0x67),
-        isTrue);
-    expect(
-        StringUtilities.startsWith5(
-            "abcdefghi", 4, 0x65, 0x66, 0x67, 0x68, 0x69),
-        isTrue);
-    expect(
-        StringUtilities.startsWith5(
-            "abcdefghi", 0, 0x61, 0x62, 0x63, 0x62, 0x61),
-        isFalse);
-    // missing
-  }
-
-  void test_startsWith6() {
-    expect(
-        StringUtilities.startsWith6(
-            "abcdef", 0, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66),
-        isTrue);
-    expect(
-        StringUtilities.startsWith6(
-            "abcdefghi", 0, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66),
-        isTrue);
-    expect(
-        StringUtilities.startsWith6(
-            "abcdefghi", 2, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68),
-        isTrue);
-    expect(
-        StringUtilities.startsWith6(
-            "abcdefghi", 3, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69),
-        isTrue);
-    expect(
-        StringUtilities.startsWith6(
-            "abcdefghi", 0, 0x61, 0x62, 0x63, 0x64, 0x65, 0x67),
-        isFalse);
-    // missing
-  }
-
-  void test_substringBefore() {
-    expect(StringUtilities.substringBefore(null, ""), null);
-    expect(StringUtilities.substringBefore(null, "a"), null);
-    expect(StringUtilities.substringBefore("", "a"), "");
-    expect(StringUtilities.substringBefore("abc", "a"), "");
-    expect(StringUtilities.substringBefore("abcba", "b"), "a");
-    expect(StringUtilities.substringBefore("abc", "c"), "ab");
-    expect(StringUtilities.substringBefore("abc", "d"), "abc");
-    expect(StringUtilities.substringBefore("abc", ""), "");
-    expect(StringUtilities.substringBefore("abc", null), "abc");
-  }
-
-  void test_substringBeforeChar() {
-    expect(StringUtilities.substringBeforeChar("", 0x61), "");
-    expect(StringUtilities.substringBeforeChar("abc", 0x61), "");
-    expect(StringUtilities.substringBeforeChar("abcba", 0x62), "a");
-    expect(StringUtilities.substringBeforeChar("abc", 0x63), "ab");
-    expect(StringUtilities.substringBeforeChar("abc", 0x64), "abc");
-  }
-}
diff --git a/pkg/analyzer/test/resource_utils.dart b/pkg/analyzer/test/resource_utils.dart
index 3337265..8d84e18 100644
--- a/pkg/analyzer/test/resource_utils.dart
+++ b/pkg/analyzer/test/resource_utils.dart
@@ -6,7 +6,6 @@
 
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
-import 'package:analyzer/src/generated/source.dart';
 import 'package:path/path.dart' as path;
 import 'package:test/test.dart';
 
@@ -88,11 +87,6 @@
   Folder getFolder(String path) => _provider.getFolder(_assertPath(path));
 
   @override
-  Future<List<int>> getModificationTimes(List<Source> sources) async {
-    return sources.map((source) => 0).toList();
-  }
-
-  @override
   Resource getResource(String path) => _provider.getResource(_assertPath(path));
 
   @override
diff --git a/pkg/analyzer/test/src/clients/dart_style/rewrite_cascade_test.dart b/pkg/analyzer/test/src/clients/dart_style/rewrite_cascade_test.dart
new file mode 100644
index 0000000..81d2486
--- /dev/null
+++ b/pkg/analyzer/test/src/clients/dart_style/rewrite_cascade_test.dart
@@ -0,0 +1,121 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analyzer/dart/analysis/features.dart';
+import 'package:analyzer/dart/analysis/utilities.dart';
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/src/clients/dart_style/rewrite_cascade.dart';
+import 'package:analyzer/src/test_utilities/find_node.dart';
+import 'package:test/test.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(RewriteCascadeTest);
+  });
+}
+
+@reflectiveTest
+class RewriteCascadeTest {
+  test_fixCascadeByParenthesizingTarget() {
+    const pairs = {
+      'c ? a : b..method();': '(c ? a : b)..method();',
+      'a ?? b..method();': '(a ?? b)..method();',
+      'a && b..method();': '(a && b)..method();',
+      'a || b..method();': '(a || b)..method();',
+      'a == b..method();': '(a == b)..method();',
+      'a != b..method();': '(a != b)..method();',
+      'a < b..method();': '(a < b)..method();',
+      'a > b..method();': '(a > b)..method();',
+      'a <= b..method();': '(a <= b)..method();',
+      'a >= b..method();': '(a >= b)..method();',
+      'a ^ b..method();': '(a ^ b)..method();',
+      'a | b..method();': '(a | b)..method();',
+      'a << b..method();': '(a << b)..method();',
+      'a >> b..method();': '(a >> b)..method();',
+      'a + b..method();': '(a + b)..method();',
+      'a - b..method();': '(a - b)..method();',
+      'a * b..method();': '(a * b)..method();',
+      'a / b..method();': '(a / b)..method();',
+      'a ~/ b..method();': '(a ~/ b)..method();',
+      '-a..method();': '(-a)..method();',
+      '!a..method();': '(!a)..method();',
+      '~a..method();': '(~a)..method();',
+      'a++..method();': '(a++)..method();',
+      'a--..method();': '(a--)..method();',
+    };
+
+    void assertSingle({
+      required String input,
+      required String expected,
+    }) {
+      var statement = _parseStringToFindNode('''
+void f() {
+  $input
+}
+''').expressionStatement(input);
+      var result = fixCascadeByParenthesizingTarget(
+        expressionStatement: statement,
+        cascadeExpression: statement.expression as CascadeExpression,
+      );
+      expect(result.toSource(), expected);
+      expect(result.semicolon, same(statement.semicolon));
+    }
+
+    for (var entry in pairs.entries) {
+      assertSingle(
+        input: entry.key,
+        expected: entry.value,
+      );
+    }
+  }
+
+  test_insertCascadeTargetIntoExpression() {
+    void assertSingle({
+      required String input,
+      required String expected,
+    }) {
+      var statement = _parseStringToFindNode('''
+void f() {
+  $input;
+    }
+    ''').expressionStatement(input);
+      var cascadeExpression = statement.expression as CascadeExpression;
+      var result = insertCascadeTargetIntoExpression(
+        expression: cascadeExpression.cascadeSections.single,
+        cascadeTarget: cascadeExpression.target,
+      );
+      expect(result.toSource(), expected);
+    }
+
+    const pairs = {
+      'obj..method()': 'obj.method()',
+      'obj..getter': 'obj.getter',
+      'obj..setter = 3': 'obj.setter = 3',
+      'obj..[subscript] = 3': 'obj[subscript] = 3',
+      'obj?..[subscript] = 3': 'obj?[subscript] = 3',
+      'obj..index[subscript] = 3': 'obj.index[subscript] = 3',
+      'obj..index?[subscript] = 3': 'obj.index?[subscript] = 3',
+      // Nested
+      'obj..foo().bar().method()': 'obj.foo().bar().method()',
+      'obj..foo.bar.getter': 'obj.foo.bar.getter',
+      'obj..foo.bar.setter = 0': 'obj.foo.bar.setter = 0',
+    };
+
+    for (var entry in pairs.entries) {
+      assertSingle(
+        input: entry.key,
+        expected: entry.value,
+      );
+    }
+  }
+
+  FindNode _parseStringToFindNode(String content) {
+    var parseResult = parseString(
+      content: content,
+      featureSet: FeatureSet.latestLanguageVersion(),
+    );
+    return FindNode(parseResult.content, parseResult.unit);
+  }
+}
diff --git a/pkg/analyzer/test/src/clients/dart_style/test_all.dart b/pkg/analyzer/test/src/clients/dart_style/test_all.dart
new file mode 100644
index 0000000..d5179bd
--- /dev/null
+++ b/pkg/analyzer/test/src/clients/dart_style/test_all.dart
@@ -0,0 +1,13 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import 'rewrite_cascade_test.dart' as rewrite_cascade;
+
+main() {
+  defineReflectiveSuite(() {
+    rewrite_cascade.main();
+  }, name: 'dart_style');
+}
diff --git a/pkg/analyzer/test/src/clients/test_all.dart b/pkg/analyzer/test/src/clients/test_all.dart
new file mode 100644
index 0000000..5118a6b
--- /dev/null
+++ b/pkg/analyzer/test/src/clients/test_all.dart
@@ -0,0 +1,13 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import 'dart_style/test_all.dart' as dart_style;
+
+main() {
+  defineReflectiveSuite(() {
+    dart_style.main();
+  }, name: 'clients');
+}
diff --git a/pkg/analyzer/test/src/dart/analysis/driver_caching_test.dart b/pkg/analyzer/test/src/dart/analysis/driver_caching_test.dart
index 58450c4..cabe570 100644
--- a/pkg/analyzer/test/src/dart/analysis/driver_caching_test.dart
+++ b/pkg/analyzer/test/src/dart/analysis/driver_caching_test.dart
@@ -4,7 +4,7 @@
 
 import 'package:analyzer/dart/analysis/results.dart';
 import 'package:analyzer/error/error.dart';
-import 'package:analyzer/src/dart/error/lint_codes.dart';
+import 'package:analyzer/src/error/codes.dart';
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
@@ -25,6 +25,38 @@
     return driver.test.libraryContextTestView.linkedCycles;
   }
 
+  test_analysisOptions_strictCasts() async {
+    useEmptyByteStore();
+
+    // Configure `strict-casts: false`.
+    writeTestPackageAnalysisOptionsFile(
+      AnalysisOptionsFileConfig(
+        strictCasts: false,
+      ),
+    );
+
+    newFile(testFilePath, content: r'''
+dynamic a = 0;
+int b = a;
+''');
+
+    // `strict-cast: false`, so no errors.
+    assertErrorsInList(await _computeTestFileErrors(), []);
+
+    // Configure `strict-casts: true`.
+    disposeAnalysisContextCollection();
+    writeTestPackageAnalysisOptionsFile(
+      AnalysisOptionsFileConfig(
+        strictCasts: true,
+      ),
+    );
+
+    // `strict-cast: true`, so has errors.
+    assertErrorsInList(await _computeTestFileErrors(), [
+      error(CompileTimeErrorCode.INVALID_ASSIGNMENT, 23, 1),
+    ]);
+  }
+
   test_change_factoryConstructor_addEqNothing() async {
     await resolveTestCode(r'''
 class A {
diff --git a/pkg/analyzer/test/src/dart/analysis/driver_test.dart b/pkg/analyzer/test/src/dart/analysis/driver_test.dart
index 252bab2..cb4869d 100644
--- a/pkg/analyzer/test/src/dart/analysis/driver_test.dart
+++ b/pkg/analyzer/test/src/dart/analysis/driver_test.dart
@@ -28,12 +28,14 @@
 
 import '../../../util/element_type_matchers.dart';
 import '../../../utils.dart';
+import '../resolution/context_collection_resolution.dart';
 import 'base.dart';
 
 main() {
   defineReflectiveSuite(() {
     defineReflectiveTests(AnalysisDriverSchedulerTest);
     defineReflectiveTests(AnalysisDriverTest);
+    defineReflectiveTests(AnalysisDriver_BazelWorkspaceTest);
   });
 }
 
@@ -50,6 +52,56 @@
 }
 
 @reflectiveTest
+class AnalysisDriver_BazelWorkspaceTest extends BazelWorkspaceResolutionTest {
+  void test_nestedLib_notCanonicalUri() async {
+    var outerLibPath = '$workspaceRootPath/my/outer/lib';
+
+    var innerPath = convertPath('$outerLibPath/inner/lib/b.dart');
+    var innerUri = Uri.parse('package:my.outer.lib.inner/b.dart');
+    newFile(innerPath, content: 'class B {}');
+
+    var analysisSession = contextFor(innerPath).currentSession;
+
+    void assertInnerUri(ResolvedUnitResult result) {
+      var innerLibrary = result.libraryElement.importedLibraries
+          .where((e) => e.source.fullName == innerPath)
+          .single;
+      expect(innerLibrary.source.uri, innerUri);
+    }
+
+    // Reference "inner" using a non-canonical URI.
+    {
+      var a = newFile(convertPath('$outerLibPath/a.dart'), content: r'''
+import 'inner/lib/b.dart';
+''');
+      var result = await analysisSession.getResolvedUnit(a.path);
+      result as ResolvedUnitResult;
+      assertInnerUri(result);
+    }
+
+    // Reference "inner" using the canonical URI, via relative.
+    {
+      var c = newFile('$outerLibPath/inner/lib/c.dart', content: r'''
+import 'b.dart';
+''');
+      var result = await analysisSession.getResolvedUnit(c.path);
+      result as ResolvedUnitResult;
+      assertInnerUri(result);
+    }
+
+    // Reference "inner" using the canonical URI, via absolute.
+    {
+      var d = newFile('$outerLibPath/inner/lib/d.dart', content: '''
+import '$innerUri';
+''');
+      var result = await analysisSession.getResolvedUnit(d.path);
+      result as ResolvedUnitResult;
+      assertInnerUri(result);
+    }
+  }
+}
+
+@reflectiveTest
 class AnalysisDriverSchedulerTest with ResourceProviderMixin {
   final ByteStore byteStore = MemoryByteStore();
 
@@ -3373,10 +3425,6 @@
 }
 
 extension on AnalysisDriver {
-  FileResult getFileSyncValid(String path) {
-    return getFileSync(path) as FileResult;
-  }
-
   Set<String> get loadedLibraryUriSet {
     var elementFactory = this.test.libraryContext!.elementFactory;
     var libraryReferences = elementFactory.rootReference.children;
@@ -3398,11 +3446,15 @@
     }
   }
 
-  Future<ResolvedUnitResult> getResultValid(String path) async {
-    return await getResult(path) as ResolvedUnitResult;
+  FileResult getFileSyncValid(String path) {
+    return getFileSync(path) as FileResult;
   }
 
   Future<LibraryElementResult> getLibraryByUriValid(String uriStr) async {
     return await getLibraryByUri(uriStr) as LibraryElementResult;
   }
+
+  Future<ResolvedUnitResult> getResultValid(String path) async {
+    return await getResult(path) as ResolvedUnitResult;
+  }
 }
diff --git a/pkg/analyzer/test/src/dart/analysis/experiments_test.dart b/pkg/analyzer/test/src/dart/analysis/experiments_test.dart
index f808c64..5eed0e1 100644
--- a/pkg/analyzer/test/src/dart/analysis/experiments_test.dart
+++ b/pkg/analyzer/test/src/dart/analysis/experiments_test.dart
@@ -30,11 +30,6 @@
     expect('${actual.major}.${actual.minor}', expectedStr);
   }
 
-  ExperimentStatus fromStrings(List<String> flags) {
-    return overrideKnownFeatures(
-        knownFeatures, () => ExperimentStatus.fromStrings(flags));
-  }
-
   ExperimentStatus fromStrings2({
     required Version sdkLanguageVersion,
     required List<String> flags,
@@ -473,193 +468,6 @@
     expect(getFlags(status), [false, true]);
   }
 
-  test_fromStrings_conflicting_flags_disable_then_enable() {
-    // Enable takes precedence because it's last
-    knownFeatures['a'] = ExperimentalFeature(
-      index: 0,
-      enableString: 'a',
-      isEnabledByDefault: false,
-      isExpired: false,
-      documentation: 'a',
-      experimentalReleaseVersion: null,
-      releaseVersion: null,
-    );
-    var status = fromStrings(['no-a', 'a']);
-    assertCurrentSdkLanguageVersion(status);
-    expect(getFlags(status), [true]);
-  }
-
-  test_fromStrings_conflicting_flags_enable_then_disable() {
-    // Disable takes precedence because it's last
-    knownFeatures['a'] = ExperimentalFeature(
-      index: 0,
-      enableString: 'a',
-      isEnabledByDefault: false,
-      isExpired: false,
-      documentation: 'a',
-      experimentalReleaseVersion: null,
-      releaseVersion: null,
-    );
-    var status = fromStrings(['a', 'no-a']);
-    assertCurrentSdkLanguageVersion(status);
-    expect(getFlags(status), [false]);
-  }
-
-  test_fromStrings_default_values() {
-    knownFeatures['a'] = ExperimentalFeature(
-      index: 0,
-      enableString: 'a',
-      isEnabledByDefault: false,
-      isExpired: false,
-      documentation: 'a',
-      experimentalReleaseVersion: null,
-      releaseVersion: null,
-    );
-    knownFeatures['b'] = ExperimentalFeature(
-      index: 1,
-      enableString: 'b',
-      isEnabledByDefault: true,
-      isExpired: false,
-      documentation: 'b',
-      experimentalReleaseVersion: null,
-      releaseVersion: Version.parse('1.0.0'),
-    );
-    var status = fromStrings([]);
-    assertCurrentSdkLanguageVersion(status);
-    expect(getFlags(status), [false, true]);
-  }
-
-  test_fromStrings_disable_disabled_feature() {
-    knownFeatures['a'] = ExperimentalFeature(
-      index: 0,
-      enableString: 'a',
-      isEnabledByDefault: false,
-      isExpired: false,
-      documentation: 'a',
-      experimentalReleaseVersion: null,
-      releaseVersion: null,
-    );
-    var status = fromStrings(['no-a']);
-    assertCurrentSdkLanguageVersion(status);
-    expect(getFlags(status), [false]);
-  }
-
-  test_fromStrings_disable_enabled_feature() {
-    knownFeatures['a'] = ExperimentalFeature(
-      index: 0,
-      enableString: 'a',
-      isEnabledByDefault: true,
-      isExpired: false,
-      documentation: 'a',
-      experimentalReleaseVersion: null,
-      releaseVersion: Version.parse('1.0.0'),
-    );
-    var status = fromStrings(['no-a']);
-    assertCurrentSdkLanguageVersion(status);
-    expect(getFlags(status), [false]);
-  }
-
-  test_fromStrings_enable_disabled_feature() {
-    knownFeatures['a'] = ExperimentalFeature(
-      index: 0,
-      enableString: 'a',
-      isEnabledByDefault: false,
-      isExpired: false,
-      documentation: 'a',
-      experimentalReleaseVersion: null,
-      releaseVersion: null,
-    );
-    var status = fromStrings(['a']);
-    assertCurrentSdkLanguageVersion(status);
-    expect(getFlags(status), [true]);
-  }
-
-  test_fromStrings_enable_enabled_feature() {
-    knownFeatures['a'] = ExperimentalFeature(
-      index: 0,
-      enableString: 'a',
-      isEnabledByDefault: true,
-      isExpired: false,
-      documentation: 'a',
-      experimentalReleaseVersion: null,
-      releaseVersion: Version.parse('1.0.0'),
-    );
-    var status = fromStrings(['a']);
-    assertCurrentSdkLanguageVersion(status);
-    expect(getFlags(status), [true]);
-  }
-
-  test_fromStrings_illegal_use_of_expired_flag_disable() {
-    // Expired flags are ignored even if they would fail validation.
-    knownFeatures['a'] = ExperimentalFeature(
-      index: 0,
-      enableString: 'a',
-      isEnabledByDefault: true,
-      isExpired: true,
-      documentation: 'a',
-      experimentalReleaseVersion: null,
-      releaseVersion: Version.parse('1.0.0'),
-    );
-    var status = fromStrings(['no-a']);
-    assertCurrentSdkLanguageVersion(status);
-    expect(getFlags(status), [true]);
-  }
-
-  test_fromStrings_illegal_use_of_expired_flag_enable() {
-    // Expired flags are ignored even if they would fail validation.
-    knownFeatures['a'] = ExperimentalFeature(
-      index: 0,
-      enableString: 'a',
-      isEnabledByDefault: false,
-      isExpired: true,
-      documentation: 'a',
-      experimentalReleaseVersion: null,
-      releaseVersion: null,
-    );
-    var status = fromStrings(['a']);
-    assertCurrentSdkLanguageVersion(status);
-    expect(getFlags(status), [false]);
-  }
-
-  test_fromStrings_unnecessary_use_of_expired_flag_disable() {
-    // Expired flags are ignored.
-    knownFeatures['a'] = ExperimentalFeature(
-      index: 0,
-      enableString: 'a',
-      isEnabledByDefault: false,
-      isExpired: true,
-      documentation: 'a',
-      experimentalReleaseVersion: null,
-      releaseVersion: null,
-    );
-    var status = fromStrings(['no-a']);
-    assertCurrentSdkLanguageVersion(status);
-    expect(getFlags(status), [false]);
-  }
-
-  test_fromStrings_unnecessary_use_of_expired_flag_enable() {
-    // Expired flags are ignored.
-    knownFeatures['a'] = ExperimentalFeature(
-      index: 0,
-      enableString: 'a',
-      isEnabledByDefault: true,
-      isExpired: true,
-      documentation: 'a',
-      experimentalReleaseVersion: null,
-      releaseVersion: Version.parse('1.0.0'),
-    );
-    var status = fromStrings(['a']);
-    assertCurrentSdkLanguageVersion(status);
-    expect(getFlags(status), [true]);
-  }
-
-  test_fromStrings_unrecognized_flag() {
-    // Unrecognized flags are ignored.
-    var status = fromStrings(['a']);
-    assertCurrentSdkLanguageVersion(status);
-    expect(getFlags(status), <Object>[]);
-  }
-
   test_validateFlagCombination_disable_then_enable() {
     knownFeatures['a'] = ExperimentalFeature(
       index: 0,
diff --git a/pkg/analyzer/test/src/dart/analysis/file_state_test.dart b/pkg/analyzer/test/src/dart/analysis/file_state_test.dart
index f0a3e1f..539ff59 100644
--- a/pkg/analyzer/test/src/dart/analysis/file_state_test.dart
+++ b/pkg/analyzer/test/src/dart/analysis/file_state_test.dart
@@ -92,6 +92,26 @@
     expect(generatedFile.path, generatedPath);
     expect(writableFile2, same(generatedFile));
   }
+
+  void test_getFileForUri_nestedLib_notCanonicalUri() async {
+    var outerPath = convertPath('$workspaceRootPath/my/outer/lib/a.dart');
+    var outerUri = Uri.parse('package:my.outer/a.dart');
+
+    var innerPath = convertPath('/workspace/my/outer/lib/inner/lib/b.dart');
+    var innerUri = Uri.parse('package:my.outer.lib.inner/b.dart');
+
+    var analysisDriver = driverFor(outerPath);
+    var fsState = analysisDriver.fsState;
+
+    // User code might use such relative URI.
+    var innerUri2 = outerUri.resolve('inner/lib/b.dart');
+    expect(innerUri2, Uri.parse('package:my.outer/inner/lib/b.dart'));
+
+    // However the returned file must use the canonical URI.
+    var innerFile = fsState.getFileForUri(innerUri2).t1!;
+    expect(innerFile.path, innerPath);
+    expect(innerFile.uri, innerUri);
+  }
 }
 
 @reflectiveTest
diff --git a/pkg/analyzer/test/src/dart/analysis/search_test.dart b/pkg/analyzer/test/src/dart/analysis/search_test.dart
index 612ac02..91057d0 100644
--- a/pkg/analyzer/test/src/dart/analysis/search_test.dart
+++ b/pkg/analyzer/test/src/dart/analysis/search_test.dart
@@ -2400,14 +2400,6 @@
 }
 
 extension on List<Declaration> {
-  void assertNo(String name) {
-    for (var declaration in this) {
-      if (declaration.name == name) {
-        fail('Unexpected declaration $name');
-      }
-    }
-  }
-
   Declaration assertHas(String name, DeclarationKind kind,
       {int? offset,
       int? codeOffset,
@@ -2432,4 +2424,12 @@
     fail('Expected to find (name=$name, kind=$kind, offset=$offset, '
         'codeOffset=$codeOffset, codeLength=$codeLength) in\n$actual');
   }
+
+  void assertNo(String name) {
+    for (var declaration in this) {
+      if (declaration.name == name) {
+        fail('Unexpected declaration $name');
+      }
+    }
+  }
 }
diff --git a/pkg/analyzer/test/src/dart/analysis/session_test.dart b/pkg/analyzer/test/src/dart/analysis/session_test.dart
index 9512475..5a90033 100644
--- a/pkg/analyzer/test/src/dart/analysis/session_test.dart
+++ b/pkg/analyzer/test/src/dart/analysis/session_test.dart
@@ -641,40 +641,40 @@
 }
 
 extension on AnalysisSession {
-  Future<UnitElementResult> getUnitElementValid(String path) async {
-    return await getUnitElement(path) as UnitElementResult;
-  }
-
-  ParsedLibraryResult getParsedLibraryValid(String path) {
-    return getParsedLibrary(path) as ParsedLibraryResult;
+  Future<ErrorsResult> getErrorsValid(String path) async {
+    return await getErrors(path) as ErrorsResult;
   }
 
   FileResult getFileValid(String path) {
     return getFile(path) as FileResult;
   }
 
-  ParsedUnitResult getParsedUnitValid(String path) {
-    return getParsedUnit(path) as ParsedUnitResult;
-  }
-
-  Future<ResolvedLibraryResult> getResolvedLibraryValid(String path) async {
-    return await getResolvedLibrary(path) as ResolvedLibraryResult;
-  }
-
   Future<LibraryElementResult> getLibraryByUriValid(String path) async {
     return await getLibraryByUri(path) as LibraryElementResult;
   }
 
+  ParsedLibraryResult getParsedLibraryByElementValid(LibraryElement element) {
+    return getParsedLibraryByElement(element) as ParsedLibraryResult;
+  }
+
+  ParsedLibraryResult getParsedLibraryValid(String path) {
+    return getParsedLibrary(path) as ParsedLibraryResult;
+  }
+
+  ParsedUnitResult getParsedUnitValid(String path) {
+    return getParsedUnit(path) as ParsedUnitResult;
+  }
+
   Future<ResolvedLibraryResult> getResolvedLibraryByElementValid(
       LibraryElement element) async {
     return await getResolvedLibraryByElement(element) as ResolvedLibraryResult;
   }
 
-  ParsedLibraryResult getParsedLibraryByElementValid(LibraryElement element) {
-    return getParsedLibraryByElement(element) as ParsedLibraryResult;
+  Future<ResolvedLibraryResult> getResolvedLibraryValid(String path) async {
+    return await getResolvedLibrary(path) as ResolvedLibraryResult;
   }
 
-  Future<ErrorsResult> getErrorsValid(String path) async {
-    return await getErrors(path) as ErrorsResult;
+  Future<UnitElementResult> getUnitElementValid(String path) async {
+    return await getUnitElement(path) as UnitElementResult;
   }
 }
diff --git a/pkg/analyzer/test/src/dart/ast/to_source_visitor_test.dart b/pkg/analyzer/test/src/dart/ast/to_source_visitor_test.dart
index 9914458..082ba9d 100644
--- a/pkg/analyzer/test/src/dart/ast/to_source_visitor_test.dart
+++ b/pkg/analyzer/test/src/dart/ast/to_source_visitor_test.dart
@@ -2,25 +2,28 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+import 'package:analyzer/dart/analysis/features.dart';
 import 'package:analyzer/dart/analysis/utilities.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
+import 'package:analyzer/src/dart/analysis/experiments.dart';
 import 'package:analyzer/src/dart/ast/ast_factory.dart';
 import 'package:analyzer/src/dart/ast/to_source_visitor.dart';
 import 'package:analyzer/src/generated/testing/ast_test_factory.dart';
 import 'package:analyzer/src/generated/testing/token_factory.dart';
 import 'package:analyzer/src/summary2/ast_binary_tokens.dart';
+import 'package:analyzer/src/test_utilities/find_node.dart';
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
 main() {
   defineReflectiveSuite(() {
-    defineReflectiveTests(ToSourceVisitor2Test);
+    defineReflectiveTests(ToSourceVisitorTest);
   });
 }
 
 @reflectiveTest
-class ToSourceVisitor2Test {
+class ToSourceVisitorTest {
   void test_visitAdjacentStrings() {
     _assertSource(
         "'a' 'b'",
@@ -208,6 +211,13 @@
             Keyword.ABSTRACT, "C", null, null, null, null));
   }
 
+  void test_visitClassDeclaration_abstractMacro() {
+    ClassDeclaration declaration = AstTestFactory.classDeclaration(
+        Keyword.ABSTRACT, "C", null, null, null, null,
+        isMacro: true);
+    _assertSource("abstract macro class C {}", declaration);
+  }
+
   void test_visitClassDeclaration_empty() {
     _assertSource("class C {}",
         AstTestFactory.classDeclaration(null, "C", null, null, null, null));
@@ -268,15 +278,23 @@
             AstTestFactory.implementsClause([AstTestFactory.namedType4("B")])));
   }
 
+  void test_visitClassDeclaration_macro() {
+    ClassDeclaration declaration = AstTestFactory.classDeclaration(
+        null, "C", null, null, null, null,
+        isMacro: true);
+    _assertSource("macro class C {}", declaration);
+  }
+
   void test_visitClassDeclaration_multipleMember() {
     _assertSource(
         "class C {var a; var b;}",
-        AstTestFactory.classDeclaration(null, "C", null, null, null, null, [
-          AstTestFactory.fieldDeclaration2(
-              false, Keyword.VAR, [AstTestFactory.variableDeclaration("a")]),
-          AstTestFactory.fieldDeclaration2(
-              false, Keyword.VAR, [AstTestFactory.variableDeclaration("b")])
-        ]));
+        AstTestFactory.classDeclaration(null, "C", null, null, null, null,
+            members: [
+              AstTestFactory.fieldDeclaration2(false, Keyword.VAR,
+                  [AstTestFactory.variableDeclaration("a")]),
+              AstTestFactory.fieldDeclaration2(
+                  false, Keyword.VAR, [AstTestFactory.variableDeclaration("b")])
+            ]));
   }
 
   void test_visitClassDeclaration_parameters() {
@@ -349,10 +367,11 @@
   void test_visitClassDeclaration_singleMember() {
     _assertSource(
         "class C {var a;}",
-        AstTestFactory.classDeclaration(null, "C", null, null, null, null, [
-          AstTestFactory.fieldDeclaration2(
-              false, Keyword.VAR, [AstTestFactory.variableDeclaration("a")])
-        ]));
+        AstTestFactory.classDeclaration(null, "C", null, null, null, null,
+            members: [
+              AstTestFactory.fieldDeclaration2(
+                  false, Keyword.VAR, [AstTestFactory.variableDeclaration("a")])
+            ]));
   }
 
   void test_visitClassDeclaration_withMetadata() {
@@ -387,6 +406,19 @@
             AstTestFactory.implementsClause([AstTestFactory.namedType4("I")])));
   }
 
+  void test_visitClassTypeAlias_abstractMacro() {
+    _assertSource(
+        "abstract macro class C = S with M1;",
+        AstTestFactory.classTypeAlias(
+            "C",
+            null,
+            Keyword.ABSTRACT,
+            AstTestFactory.namedType4("S"),
+            AstTestFactory.withClause([AstTestFactory.namedType4("M1")]),
+            null,
+            isMacro: true));
+  }
+
   void test_visitClassTypeAlias_generic() {
     _assertSource(
         "class C<E> = S<E> with M1<E>;",
@@ -413,6 +445,19 @@
             AstTestFactory.implementsClause([AstTestFactory.namedType4("I")])));
   }
 
+  void test_visitClassTypeAlias_macro() {
+    _assertSource(
+        "macro class C = S with M1;",
+        AstTestFactory.classTypeAlias(
+            "C",
+            null,
+            null,
+            AstTestFactory.namedType4("S"),
+            AstTestFactory.withClause([AstTestFactory.namedType4("M1")]),
+            null,
+            isMacro: true));
+  }
+
   void test_visitClassTypeAlias_minimal() {
     _assertSource(
         "class C = S with M1;",
@@ -765,14 +810,62 @@
     _assertSource(";", AstTestFactory.emptyStatement());
   }
 
-  void test_visitEnumDeclaration_multiple() {
-    _assertSource("enum E {ONE, TWO}",
-        AstTestFactory.enumDeclaration2("E", ["ONE", "TWO"]));
+  void test_visitEnumDeclaration_constants_multiple() {
+    var findNode = _parseStringToFindNode(r'''
+enum E {one, two}
+''');
+    _assertSource(
+      'enum E {one, two}',
+      findNode.enumDeclaration('E'),
+    );
   }
 
-  void test_visitEnumDeclaration_single() {
+  void test_visitEnumDeclaration_constants_single() {
+    var findNode = _parseStringToFindNode(r'''
+enum E {one}
+''');
     _assertSource(
-        "enum E {ONE}", AstTestFactory.enumDeclaration2("E", ["ONE"]));
+      'enum E {one}',
+      findNode.enumDeclaration('E'),
+    );
+  }
+
+  void test_visitEnumDeclaration_field_constructor() {
+    var findNode = _parseStringToFindNode(r'''
+enum E {
+  one, two;
+  final int field;
+  E(this.field);
+}
+''');
+    _assertSource(
+      'enum E {one, two; final int field; E(this.field);}',
+      findNode.enumDeclaration('enum E'),
+    );
+  }
+
+  void test_visitEnumDeclaration_method() {
+    var findNode = _parseStringToFindNode(r'''
+enum E {
+  one, two;
+  void myMethod() {}
+  int get myGetter => 0;
+}
+''');
+    _assertSource(
+      'enum E {one, two; void myMethod() {} int get myGetter => 0;}',
+      findNode.enumDeclaration('enum E'),
+    );
+  }
+
+  void test_visitEnumDeclaration_withoutMembers() {
+    var findNode = _parseStringToFindNode(r'''
+enum E<T> with M1, M2 implements I1, I2 {one, two}
+''');
+    _assertSource(
+      'enum E<T> with M1, M2 implements I1, I2 {one, two}',
+      findNode.enumDeclaration('E'),
+    );
   }
 
   void test_visitExportDirective_combinator() {
@@ -3349,11 +3442,25 @@
         AstTestFactory.yieldEachStatement(AstTestFactory.identifier3("e")));
   }
 
-  /// Assert that a `ToSourceVisitor2` will produce the [expectedSource] when
+  /// Assert that a [ToSourceVisitor] will produce the [expectedSource] when
   /// visiting the given [node].
   void _assertSource(String expectedSource, AstNode node) {
     StringBuffer buffer = StringBuffer();
     node.accept(ToSourceVisitor(buffer));
     expect(buffer.toString(), expectedSource);
   }
+
+  FindNode _parseStringToFindNode(String content) {
+    var parseResult = parseString(
+      content: content,
+      featureSet: FeatureSet.fromEnableFlags2(
+        sdkLanguageVersion: ExperimentStatus.currentVersion,
+        flags: [
+          Feature.enhanced_enums.enableString,
+          Feature.super_parameters.enableString,
+        ],
+      ),
+    );
+    return FindNode(parseResult.content, parseResult.unit);
+  }
 }
diff --git a/pkg/analyzer/test/src/dart/element/class_element_test.dart b/pkg/analyzer/test/src/dart/element/class_element_test.dart
index c6ed690..9505982 100644
--- a/pkg/analyzer/test/src/dart/element/class_element_test.dart
+++ b/pkg/analyzer/test/src/dart/element/class_element_test.dart
@@ -1331,10 +1331,6 @@
 }
 
 extension on ClassElement {
-  MethodElement? _lookUpInheritedMethod(String name) {
-    return lookUpInheritedMethod(name, library);
-  }
-
   PropertyAccessorElement? _lookUpInheritedConcreteGetter(String name) {
     return lookUpInheritedConcreteGetter(name, library);
   }
@@ -1346,4 +1342,8 @@
   PropertyAccessorElement? _lookUpInheritedConcreteSetter(String name) {
     return lookUpInheritedConcreteSetter(name, library);
   }
+
+  MethodElement? _lookUpInheritedMethod(String name) {
+    return lookUpInheritedMethod(name, library);
+  }
 }
diff --git a/pkg/analyzer/test/src/dart/element/element_test.dart b/pkg/analyzer/test/src/dart/element/element_test.dart
index 0ac00a2..2b46b93 100644
--- a/pkg/analyzer/test/src/dart/element/element_test.dart
+++ b/pkg/analyzer/test/src/dart/element/element_test.dart
@@ -13,7 +13,6 @@
 import 'package:analyzer/src/dart/element/type.dart';
 import 'package:analyzer/src/generated/engine.dart' show AnalysisContext;
 import 'package:analyzer/src/generated/testing/element_factory.dart';
-import 'package:analyzer/src/generated/testing/test_type_provider.dart';
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
@@ -1269,357 +1268,6 @@
     expect(0 == typeA.hashCode, isFalse);
   }
 
-  @deprecated
-  void test_lookUpGetter_implemented() {
-    //
-    // class A { g {} }
-    //
-    var classA = class_(name: 'A');
-    String getterName = "g";
-    PropertyAccessorElement getterG =
-        ElementFactory.getterElement(getterName, false, intNone);
-    classA.accessors = <PropertyAccessorElement>[getterG];
-    InterfaceType typeA = interfaceTypeStar(classA);
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    CompilationUnitElement unit = library.definingCompilationUnit;
-    (unit as CompilationUnitElementImpl).classes = <ClassElement>[classA];
-    expect(typeA.lookUpGetter(getterName, library), same(getterG));
-  }
-
-  @deprecated
-  void test_lookUpGetter_inherited() {
-    //
-    // class A { g {} }
-    // class B extends A {}
-    //
-    var classA = class_(name: 'A');
-    String getterName = "g";
-    PropertyAccessorElement getterG =
-        ElementFactory.getterElement(getterName, false, intNone);
-    classA.accessors = <PropertyAccessorElement>[getterG];
-    ClassElementImpl classB =
-        ElementFactory.classElement("B", interfaceTypeStar(classA));
-    InterfaceType typeB = interfaceTypeStar(classB);
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    CompilationUnitElement unit = library.definingCompilationUnit;
-    (unit as CompilationUnitElementImpl).classes = <ClassElement>[
-      classA,
-      classB
-    ];
-    expect(typeB.lookUpGetter(getterName, library), same(getterG));
-  }
-
-  @deprecated
-  void test_lookUpGetter_mixin_shadowing() {
-    //
-    // class B {}
-    // class M1 { get g {} }
-    // class M2 { get g {} }
-    // class C extends B with M1, M2 {}
-    //
-    TestTypeProvider typeProvider = TestTypeProvider();
-    String getterName = 'g';
-    var classB = class_(name: 'B');
-    ClassElementImpl classM1 = ElementFactory.classElement2('M1');
-    PropertyAccessorElementImpl getterM1g = ElementFactory.getterElement(
-        getterName, false, typeProvider.dynamicType);
-    classM1.accessors = <PropertyAccessorElement>[getterM1g];
-    ClassElementImpl classM2 = ElementFactory.classElement2('M2');
-    PropertyAccessorElementImpl getterM2g = ElementFactory.getterElement(
-        getterName, false, typeProvider.dynamicType);
-    classM2.accessors = <PropertyAccessorElement>[getterM2g];
-    ClassElementImpl classC =
-        ElementFactory.classElement('C', interfaceTypeStar(classB));
-    classC.mixins = <InterfaceType>[
-      interfaceTypeStar(classM1),
-      interfaceTypeStar(classM2)
-    ];
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    var unit = library.definingCompilationUnit as CompilationUnitElementImpl;
-    unit.classes = <ClassElement>[classB, classM1, classM2, classC];
-    expect(
-        interfaceTypeStar(classC).lookUpGetter(getterName, library), getterM2g);
-  }
-
-  @deprecated
-  void test_lookUpGetter_recursive() {
-    //
-    // class A extends B {}
-    // class B extends A {}
-    //
-    var classA = class_(name: 'A');
-    InterfaceType typeA = interfaceTypeStar(classA);
-    var classB = ElementFactory.classElement("B", typeA);
-    classA.supertype = interfaceTypeStar(classB);
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    CompilationUnitElement unit = library.definingCompilationUnit;
-    (unit as CompilationUnitElementImpl).classes = <ClassElement>[
-      classA,
-      classB
-    ];
-    expect(typeA.lookUpGetter("g", library), isNull);
-  }
-
-  @deprecated
-  void test_lookUpGetter_unimplemented() {
-    //
-    // class A {}
-    //
-    var classA = class_(name: 'A');
-    InterfaceType typeA = interfaceTypeStar(classA);
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    CompilationUnitElement unit = library.definingCompilationUnit;
-    (unit as CompilationUnitElementImpl).classes = <ClassElement>[classA];
-    expect(typeA.lookUpGetter("g", library), isNull);
-  }
-
-  @deprecated
-  void test_lookUpMethod_implemented() {
-    //
-    // class A { m() {} }
-    //
-    var classA = class_(name: 'A');
-    String methodName = "m";
-    MethodElementImpl methodM =
-        ElementFactory.methodElement(methodName, intNone);
-    classA.methods = <MethodElement>[methodM];
-    InterfaceType typeA = interfaceTypeStar(classA);
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    CompilationUnitElement unit = library.definingCompilationUnit;
-    (unit as CompilationUnitElementImpl).classes = <ClassElement>[classA];
-    expect(typeA.lookUpMethod(methodName, library), same(methodM));
-  }
-
-  @deprecated
-  void test_lookUpMethod_inherited() {
-    //
-    // class A { m() {} }
-    // class B extends A {}
-    //
-    var classA = class_(name: 'A');
-    String methodName = "m";
-    MethodElementImpl methodM =
-        ElementFactory.methodElement(methodName, intNone);
-    classA.methods = <MethodElement>[methodM];
-    ClassElementImpl classB =
-        ElementFactory.classElement("B", interfaceTypeStar(classA));
-    InterfaceType typeB = interfaceTypeStar(classB);
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    CompilationUnitElement unit = library.definingCompilationUnit;
-    (unit as CompilationUnitElementImpl).classes = <ClassElement>[
-      classA,
-      classB
-    ];
-    expect(typeB.lookUpMethod(methodName, library), same(methodM));
-  }
-
-  @deprecated
-  void test_lookUpMethod_mixin_shadowing() {
-    //
-    // class B {}
-    // class M1 { m() {} }
-    // class M2 { m() {} }
-    // class C extends B with M1, M2 {}
-    //
-    String methodName = 'm';
-    var classB = class_(name: 'B');
-    ClassElementImpl classM1 = ElementFactory.classElement2('M1');
-    MethodElementImpl methodM1m =
-        ElementFactory.methodElement(methodName, intNone);
-    classM1.methods = <MethodElement>[methodM1m];
-    ClassElementImpl classM2 = ElementFactory.classElement2('M2');
-    MethodElementImpl methodM2m =
-        ElementFactory.methodElement(methodName, intNone);
-    classM2.methods = <MethodElement>[methodM2m];
-    ClassElementImpl classC =
-        ElementFactory.classElement('C', interfaceTypeStar(classB));
-    classC.mixins = <InterfaceType>[
-      interfaceTypeStar(classM1),
-      interfaceTypeStar(classM2)
-    ];
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    var unit = library.definingCompilationUnit as CompilationUnitElementImpl;
-    unit.classes = <ClassElement>[classB, classM1, classM2, classC];
-    expect(
-        interfaceTypeStar(classC).lookUpMethod(methodName, library), methodM2m);
-  }
-
-  @FailingTest(issue: 'https://github.com/dart-lang/sdk/issues/44522')
-  @deprecated
-  void test_lookUpMethod_parameterized() {
-    //
-    // class A<E> { E m(E p) {} }
-    // class B<F> extends A<F> {}
-    //
-    var E = typeParameter('E');
-    var A = class_(name: 'A', typeParameters: [E]);
-    DartType typeE = typeParameterTypeStar(E);
-    String methodName = "m";
-    MethodElementImpl methodM =
-        ElementFactory.methodElement(methodName, typeE, [typeE]);
-    A.methods = <MethodElement>[methodM];
-
-    var F = typeParameter('F');
-    var B = class_(
-      name: 'B',
-      typeParameters: [F],
-      superType: interfaceTypeStar(A, typeArguments: [
-        typeParameterTypeStar(F),
-      ]),
-    );
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    CompilationUnitElement unit = library.definingCompilationUnit;
-    (unit as CompilationUnitElementImpl).classes = <ClassElement>[A];
-    //
-    // B<I>
-    //
-    var typeI = interfaceTypeStar(class_(name: 'I'));
-    var typeBI = interfaceTypeStar(B, typeArguments: <DartType>[typeI]);
-    MethodElement method = typeBI.lookUpMethod(methodName, library)!;
-    expect(method, isNotNull);
-    FunctionType methodType = method.type;
-    expect(methodType.returnType, same(typeI));
-    List<DartType> parameterTypes = methodType.normalParameterTypes;
-    expect(parameterTypes, hasLength(1));
-    expect(parameterTypes[0], same(typeI));
-  }
-
-  @deprecated
-  void test_lookUpMethod_recursive() {
-    //
-    // class A extends B {}
-    // class B extends A {}
-    //
-    var classA = class_(name: 'A');
-    InterfaceType typeA = interfaceTypeStar(classA);
-    var classB = ElementFactory.classElement("B", typeA);
-    classA.supertype = interfaceTypeStar(classB);
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    CompilationUnitElement unit = library.definingCompilationUnit;
-    (unit as CompilationUnitElementImpl).classes = <ClassElement>[
-      classA,
-      classB
-    ];
-    expect(typeA.lookUpMethod("m", library), isNull);
-  }
-
-  @deprecated
-  void test_lookUpMethod_unimplemented() {
-    //
-    // class A {}
-    //
-    var classA = class_(name: 'A');
-    InterfaceType typeA = interfaceTypeStar(classA);
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    CompilationUnitElement unit = library.definingCompilationUnit;
-    (unit as CompilationUnitElementImpl).classes = <ClassElement>[classA];
-    expect(typeA.lookUpMethod("m", library), isNull);
-  }
-
-  @deprecated
-  void test_lookUpSetter_implemented() {
-    //
-    // class A { s(x) {} }
-    //
-    var classA = class_(name: 'A');
-    String setterName = "s";
-    PropertyAccessorElement setterS =
-        ElementFactory.setterElement(setterName, false, intNone);
-    classA.accessors = <PropertyAccessorElement>[setterS];
-    InterfaceType typeA = interfaceTypeStar(classA);
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    CompilationUnitElement unit = library.definingCompilationUnit;
-    (unit as CompilationUnitElementImpl).classes = <ClassElement>[classA];
-    expect(typeA.lookUpSetter(setterName, library), same(setterS));
-  }
-
-  @deprecated
-  void test_lookUpSetter_inherited() {
-    //
-    // class A { s(x) {} }
-    // class B extends A {}
-    //
-    var classA = class_(name: 'A');
-    String setterName = "g";
-    PropertyAccessorElement setterS =
-        ElementFactory.setterElement(setterName, false, intNone);
-    classA.accessors = <PropertyAccessorElement>[setterS];
-    ClassElementImpl classB =
-        ElementFactory.classElement("B", interfaceTypeStar(classA));
-    InterfaceType typeB = interfaceTypeStar(classB);
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    CompilationUnitElement unit = library.definingCompilationUnit;
-    (unit as CompilationUnitElementImpl).classes = <ClassElement>[
-      classA,
-      classB
-    ];
-    expect(typeB.lookUpSetter(setterName, library), same(setterS));
-  }
-
-  @deprecated
-  void test_lookUpSetter_mixin_shadowing() {
-    //
-    // class B {}
-    // class M1 { set s() {} }
-    // class M2 { set s() {} }
-    // class C extends B with M1, M2 {}
-    //
-    TestTypeProvider typeProvider = TestTypeProvider();
-    String setterName = 's';
-    var classB = class_(name: 'B');
-    ClassElementImpl classM1 = ElementFactory.classElement2('M1');
-    PropertyAccessorElementImpl setterM1g = ElementFactory.setterElement(
-        setterName, false, typeProvider.dynamicType);
-    classM1.accessors = <PropertyAccessorElement>[setterM1g];
-    ClassElementImpl classM2 = ElementFactory.classElement2('M2');
-    PropertyAccessorElementImpl setterM2g = ElementFactory.getterElement(
-        setterName, false, typeProvider.dynamicType);
-    classM2.accessors = <PropertyAccessorElement>[setterM2g];
-    ClassElementImpl classC =
-        ElementFactory.classElement('C', interfaceTypeStar(classB));
-    classC.mixins = <InterfaceType>[
-      interfaceTypeStar(classM1),
-      interfaceTypeStar(classM2)
-    ];
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    var unit = library.definingCompilationUnit as CompilationUnitElementImpl;
-    unit.classes = <ClassElement>[classB, classM1, classM2, classC];
-    expect(
-        interfaceTypeStar(classC).lookUpGetter(setterName, library), setterM2g);
-  }
-
-  @deprecated
-  void test_lookUpSetter_recursive() {
-    //
-    // class A extends B {}
-    // class B extends A {}
-    //
-    var classA = class_(name: 'A');
-    InterfaceType typeA = interfaceTypeStar(classA);
-    var classB = ElementFactory.classElement("B", typeA);
-    classA.supertype = interfaceTypeStar(classB);
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    CompilationUnitElement unit = library.definingCompilationUnit;
-    (unit as CompilationUnitElementImpl).classes = <ClassElement>[
-      classA,
-      classB
-    ];
-    expect(typeA.lookUpSetter("s", library), isNull);
-  }
-
-  @deprecated
-  void test_lookUpSetter_unimplemented() {
-    //
-    // class A {}
-    //
-    var classA = class_(name: 'A');
-    InterfaceType typeA = interfaceTypeStar(classA);
-    LibraryElementImpl library = ElementFactory.library(analysisContext, "lib");
-    CompilationUnitElement unit = library.definingCompilationUnit;
-    (unit as CompilationUnitElementImpl).classes = <ClassElement>[classA];
-    expect(typeA.lookUpSetter("s", library), isNull);
-  }
-
   void test_resolveToBound() {
     var type = interfaceTypeStar(ElementFactory.classElement2('A'));
 
diff --git a/pkg/analyzer/test/src/dart/micro/simple_file_resolver_test.dart b/pkg/analyzer/test/src/dart/micro/simple_file_resolver_test.dart
index 0b35e99..4044e88 100644
--- a/pkg/analyzer/test/src/dart/micro/simple_file_resolver_test.dart
+++ b/pkg/analyzer/test/src/dart/micro/simple_file_resolver_test.dart
@@ -7,7 +7,6 @@
 import 'package:analyzer/src/dart/ast/utilities.dart';
 import 'package:analyzer/src/dart/error/syntactic_errors.dart';
 import 'package:analyzer/src/dart/micro/cider_byte_store.dart';
-import 'package:analyzer/src/dart/micro/library_graph.dart';
 import 'package:analyzer/src/dart/micro/resolve_file.dart';
 import 'package:analyzer/src/dart/micro/utils.dart';
 import 'package:analyzer/src/error/codes.dart';
@@ -768,8 +767,7 @@
       var files = fileResolver.getFilesWithTopLevelDeclarations('a');
       expect(files, hasLength(1));
       var file = files.single;
-      expect(file.file.path, result.path);
-      expect(file.kind, FileTopLevelDeclarationKind.variable);
+      expect(file.path, result.path);
     }
 
     // Ask to check that it works when parsed.
diff --git a/pkg/analyzer/test/src/dart/resolution/comment_test.dart b/pkg/analyzer/test/src/dart/resolution/comment_test.dart
index 7735e22..16fa635 100644
--- a/pkg/analyzer/test/src/dart/resolution/comment_test.dart
+++ b/pkg/analyzer/test/src/dart/resolution/comment_test.dart
@@ -9,12 +9,612 @@
 
 main() {
   defineReflectiveSuite(() {
-    defineReflectiveTests(CommentDriverResolutionTest);
+    defineReflectiveTests(CommentDriverResolution_PrefixedIdentifierTest);
+    defineReflectiveTests(CommentDriverResolution_PropertyAccessTest);
+    defineReflectiveTests(CommentDriverResolution_SimpleIdentifierTest);
   });
 }
 
 @reflectiveTest
-class CommentDriverResolutionTest extends PubPackageResolutionTest {
+class CommentDriverResolution_PrefixedIdentifierTest
+    extends PubPackageResolutionTest {
+  test_class_constructor_named() async {
+    // TODO(srawlins): improve coverage regarding constructors, operators, the
+    // 'new' keyword, and members on an extension on a type variable
+    // (`extension <T> on T`).
+    await assertNoErrorsInCode('''
+class A {
+  A.named();
+}
+
+/// [A.named]
+void f() {}
+''');
+
+    assertElement(findNode.simple('A.named]'), findElement.class_('A'));
+    assertElement(findNode.simple('named]'), findElement.constructor('named'));
+  }
+
+  test_class_constructor_unnamedViaNew() async {
+    await assertNoErrorsInCode('''
+class A {
+  A();
+}
+
+/// [A.new]
+void f() {}
+''');
+
+    assertElement(findNode.simple('A.new'), findElement.class_('A'));
+    assertElement(findNode.simple('new]'), findElement.unnamedConstructor('A'));
+  }
+
+  test_class_instanceGetter() async {
+    await assertNoErrorsInCode('''
+class A {
+  int get foo => 0;
+}
+
+/// [A.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
+    assertElement(findNode.simple('foo]'), findElement.getter('foo'));
+  }
+
+  test_class_instanceMethod() async {
+    await assertNoErrorsInCode('''
+class A {
+  void foo() {}
+}
+
+/// [A.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
+    assertElement(findNode.simple('foo]'), findElement.method('foo'));
+  }
+
+  test_class_instanceSetter() async {
+    await assertNoErrorsInCode('''
+class A {
+  set foo(int _) {}
+}
+
+/// [A.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
+    assertElement(findNode.simple('foo]'), findElement.setter('foo'));
+  }
+
+  test_class_staticGetter() async {
+    await assertNoErrorsInCode('''
+class A {
+  static int get foo => 0;
+}
+
+/// [A.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
+    assertElement(findNode.simple('foo]'), findElement.getter('foo'));
+  }
+
+  test_class_staticMethod() async {
+    await assertNoErrorsInCode('''
+class A {
+  static void foo() {}
+}
+
+/// [A.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
+    assertElement(findNode.simple('foo]'), findElement.method('foo'));
+  }
+
+  test_class_staticSetter() async {
+    await assertNoErrorsInCode('''
+class A {
+  static set foo(int _) {}
+}
+
+/// [A.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
+    assertElement(findNode.simple('foo]'), findElement.setter('foo'));
+  }
+
+  test_extension_instanceGetter() async {
+    await assertNoErrorsInCode('''
+extension E on int {
+  int get foo => 0;
+}
+
+/// [E.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
+    assertElement(findNode.simple('foo]'), findElement.getter('foo'));
+  }
+
+  test_extension_instanceMethod() async {
+    await assertNoErrorsInCode('''
+extension E on int {
+  void foo() {}
+}
+
+/// [E.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
+    assertElement(findNode.simple('foo]'), findElement.method('foo'));
+  }
+
+  test_extension_instanceSetter() async {
+    await assertNoErrorsInCode('''
+extension E on int {
+  set foo(int _) {}
+}
+
+/// [E.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
+    assertElement(findNode.simple('foo]'), findElement.setter('foo'));
+  }
+
+  test_extension_staticGetter() async {
+    await assertNoErrorsInCode('''
+extension E on int {
+  static int get foo => 0;
+}
+
+/// [E.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
+    assertElement(findNode.simple('foo]'), findElement.getter('foo'));
+  }
+
+  test_extension_staticMethod() async {
+    await assertNoErrorsInCode('''
+extension E on int {
+  static void foo() {}
+}
+
+/// [E.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
+    assertElement(findNode.simple('foo]'), findElement.method('foo'));
+  }
+
+  test_extension_staticSetter() async {
+    await assertNoErrorsInCode('''
+extension E on int {
+  static set foo(int _) {}
+}
+
+/// [E.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
+    assertElement(findNode.simple('foo]'), findElement.setter('foo'));
+  }
+}
+
+@reflectiveTest
+class CommentDriverResolution_PropertyAccessTest
+    extends PubPackageResolutionTest {
+  test_class_constructor_named() async {
+    await assertNoErrorsInCode('''
+import '' as self;
+class A {
+  A.named();
+}
+
+/// [self.A.named]
+void f() {}
+''');
+
+    assertElement(findNode.simple('self.A.named'), findElement.prefix('self'));
+    assertElement(findNode.simple('A.named]'), findElement.class_('A'));
+    // TODO(srawlins): Set the type of named, and test it, here and below.
+    assertElement(findNode.simple('named]'), findElement.constructor('named'));
+  }
+
+  test_class_constructor_unnamedViaNew() async {
+    await assertNoErrorsInCode('''
+import '' as self;
+class A {
+  A();
+}
+
+/// [self.A.new]
+void f() {}
+''');
+
+    assertElement(findNode.simple('self.A.new'), findElement.prefix('self'));
+    assertElement(findNode.simple('A.new'), findElement.class_('A'));
+    assertElement(findNode.simple('new]'), findElement.unnamedConstructor('A'));
+  }
+
+  test_class_instanceGetter() async {
+    await assertNoErrorsInCode('''
+import '' as self;
+class A {
+  int get foo => 0;
+}
+
+/// [self.A.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('self.A.foo'), findElement.prefix('self'));
+    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
+    assertElement(findNode.simple('foo]'), findElement.getter('foo'));
+  }
+
+  test_class_instanceMethod() async {
+    await assertNoErrorsInCode('''
+import '' as self;
+class A {
+  void foo() {}
+}
+
+/// [self.A.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('self.A.foo'), findElement.prefix('self'));
+    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
+    assertElement(findNode.simple('foo]'), findElement.method('foo'));
+  }
+
+  test_class_instanceSetter() async {
+    await assertNoErrorsInCode('''
+import '' as self;
+class A {
+  set foo(int value) {}
+}
+
+/// [self.A.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('self.A.foo'), findElement.prefix('self'));
+    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
+    assertElement(findNode.simple('foo]'), findElement.setter('foo'));
+  }
+
+  test_class_staticGetter() async {
+    await assertNoErrorsInCode('''
+import '' as self;
+class A {
+  static int get foo => 0;
+}
+
+/// [self.A.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('self.A.foo'), findElement.prefix('self'));
+    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
+    assertElement(findNode.simple('foo]'), findElement.getter('foo'));
+  }
+
+  test_class_staticMethod() async {
+    await assertNoErrorsInCode('''
+import '' as self;
+class A {
+  static void foo() {}
+}
+
+/// [self.A.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('self.A.foo'), findElement.prefix('self'));
+    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
+    assertElement(findNode.simple('foo]'), findElement.method('foo'));
+  }
+
+  test_class_staticSetter() async {
+    await assertNoErrorsInCode('''
+import '' as self;
+class A {
+  static set foo(int value) {}
+}
+
+/// [self.A.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('self.A.foo'), findElement.prefix('self'));
+    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
+    assertElement(findNode.simple('foo]'), findElement.setter('foo'));
+  }
+
+  test_extension_instanceGetter() async {
+    await assertNoErrorsInCode('''
+import '' as self;
+extension E on int {
+  int get foo => 0;
+}
+
+/// [self.E.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('self.E.foo'), findElement.prefix('self'));
+    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
+    assertElement(findNode.simple('foo]'), findElement.getter('foo'));
+  }
+
+  test_extension_instanceMethod() async {
+    await assertNoErrorsInCode('''
+import '' as self;
+extension E on int {
+  void foo() {}
+}
+
+/// [self.E.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('self.E.foo'), findElement.prefix('self'));
+    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
+    assertElement(findNode.simple('foo]'), findElement.method('foo'));
+  }
+
+  test_extension_instanceSetter() async {
+    await assertNoErrorsInCode('''
+import '' as self;
+extension E on int {
+  set foo(int value) {}
+}
+
+/// [self.E.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('self.E.foo'), findElement.prefix('self'));
+    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
+    assertElement(findNode.simple('foo]'), findElement.setter('foo'));
+  }
+
+  test_extension_staticGetter() async {
+    await assertNoErrorsInCode('''
+import '' as self;
+extension E on int {
+  static int get foo => 0;
+}
+
+/// [self.E.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('self.E.foo'), findElement.prefix('self'));
+    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
+    assertElement(findNode.simple('foo]'), findElement.getter('foo'));
+  }
+
+  test_extension_staticMethod() async {
+    await assertNoErrorsInCode('''
+import '' as self;
+extension E on int {
+  static void foo() {}
+}
+
+/// [self.E.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('self.E.foo'), findElement.prefix('self'));
+    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
+    assertElement(findNode.simple('foo]'), findElement.method('foo'));
+  }
+
+  test_extension_staticSetter() async {
+    await assertNoErrorsInCode('''
+import '' as self;
+extension E on int {
+  static set foo(int value) {}
+}
+
+/// [self.E.foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('self.E.foo'), findElement.prefix('self'));
+    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
+    assertElement(findNode.simple('foo]'), findElement.setter('foo'));
+  }
+}
+
+@reflectiveTest
+class CommentDriverResolution_SimpleIdentifierTest
+    extends PubPackageResolutionTest {
+  test_associatedSetterAndGetter() async {
+    await assertNoErrorsInCode('''
+int get foo => 0;
+
+set foo(int value) {}
+
+/// [foo]
+void f() {}
+''');
+
+    assertElement(findNode.simple('foo]'), findElement.topGet('foo'));
+  }
+
+  test_associatedSetterAndGetter_setterInScope() async {
+    await assertNoErrorsInCode('''
+extension E1 on int {
+  int get foo => 0;
+}
+
+/// [foo]
+extension E2 on int {
+  set foo(int value) {}
+}
+''');
+
+    assertElement(findNode.simple('foo]'), findElement.setter('foo'));
+  }
+
+  test_beforeClass() async {
+    await assertNoErrorsInCode(r'''
+/// [foo]
+class A {
+  foo() {}
+}
+''');
+
+    assertElement(
+      findNode.simple('foo]'),
+      findElement.method('foo'),
+    );
+  }
+
+  test_beforeConstructor() async {
+    await assertNoErrorsInCode(r'''
+class A {
+  /// [p]
+  A(int p);
+}''');
+
+    assertElement(
+      findNode.simple('p]'),
+      findElement.parameter('p'),
+    );
+  }
+
+  test_beforeEnum() async {
+    await assertNoErrorsInCode(r'''
+/// This is the [Samurai] kind.
+enum Samurai {
+  /// Use [int].
+  WITH_SWORD,
+  /// Like [WITH_SWORD], but only without one.
+  WITHOUT_SWORD
+}''');
+
+    assertElement(
+      findNode.simple('Samurai]'),
+      findElement.enum_('Samurai'),
+    );
+    assertElement(
+      findNode.simple('int]'),
+      intElement,
+    );
+    assertElement(
+      findNode.simple('WITH_SWORD]'),
+      findElement.getter('WITH_SWORD'),
+    );
+  }
+
+  test_beforeFunction_blockBody() async {
+    await assertNoErrorsInCode(r'''
+/// [p]
+foo(int p) {}
+''');
+
+    assertElement(
+      findNode.simple('p]'),
+      findElement.parameter('p'),
+    );
+  }
+
+  test_beforeFunction_expressionBody() async {
+    await assertNoErrorsInCode(r'''
+/// [p]
+foo(int p) => null;
+''');
+
+    assertElement(
+      findNode.simple('p]'),
+      findElement.parameter('p'),
+    );
+  }
+
+  test_beforeFunctionTypeAlias() async {
+    await assertNoErrorsInCode(r'''
+/// [p]
+typedef Foo(int p);
+''');
+
+    assertElement(
+      findNode.simple('p]'),
+      findElement.parameter('p'),
+    );
+  }
+
+  test_beforeGenericTypeAlias() async {
+    await assertNoErrorsInCode(r'''
+/// Can resolve [T], [S], and [p].
+typedef Foo<T> = Function<S>(int p);
+''');
+
+    assertElement(
+      findNode.simple('T]'),
+      findElement.typeParameter('T'),
+    );
+    assertElement(findNode.simple('S]'), findElement.typeParameter('S'));
+    assertElement(
+      findNode.simple('p]'),
+      findElement.parameter('p'),
+    );
+  }
+
+  test_beforeGetter() async {
+    await assertNoErrorsInCode(r'''
+/// [int]
+get g => null;
+''');
+
+    assertElement(findNode.simple('int]'), intElement);
+  }
+
+  test_beforeMethod() async {
+    await assertNoErrorsInCode(r'''
+abstract class A {
+  /// [p1]
+  ma(int p1);
+
+  /// [p2]
+  mb(int p2);
+
+  /// [p3] and [p4]
+  mc(int p3, p4());
+
+  /// [p5]
+  md(int p5, {int p6});
+}
+''');
+
+    assertElement(findNode.simple('p1]'), findElement.parameter('p1'));
+    assertElement(findNode.simple('p2]'), findElement.parameter('p2'));
+    assertElement(findNode.simple('p3]'), findElement.parameter('p3'));
+    assertElement(findNode.simple('p4]'), findElement.parameter('p4'));
+    assertElement(findNode.simple('p5]'), findElement.parameter('p5'));
+  }
+
   test_newKeyword() async {
     await assertErrorsInCode('''
 class A {
@@ -43,312 +643,7 @@
     );
   }
 
-  test_prefixedIdentifier_class_instanceGetter() async {
-    await assertNoErrorsInCode(r'''
-class A {
-  int get foo => 0;
-}
-
-/// [A.foo]
-void f() {}
-''');
-
-    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
-    assertElement(findNode.simple('foo]'), findElement.getter('foo'));
-  }
-
-  test_prefixedIdentifier_class_instanceMethod() async {
-    await assertNoErrorsInCode(r'''
-class A {
-  void foo() {}
-}
-
-/// [A.foo]
-void f() {}
-''');
-
-    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
-    assertElement(findNode.simple('foo]'), findElement.method('foo'));
-  }
-
-  test_prefixedIdentifier_class_instanceSetter() async {
-    await assertNoErrorsInCode(r'''
-class A {
-  set foo(int _) {}
-}
-
-/// [A.foo]
-void f() {}
-''');
-
-    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
-    assertElement(findNode.simple('foo]'), findElement.setter('foo'));
-  }
-
-  test_prefixedIdentifier_class_staticGetter() async {
-    await assertNoErrorsInCode(r'''
-class A {
-  static int get foo => 0;
-}
-
-/// [A.foo]
-void f() {}
-''');
-
-    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
-    assertElement(findNode.simple('foo]'), findElement.getter('foo'));
-  }
-
-  test_prefixedIdentifier_class_staticMethod() async {
-    await assertNoErrorsInCode(r'''
-class A {
-  static void foo() {}
-}
-
-/// [A.foo]
-void f() {}
-''');
-
-    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
-    assertElement(findNode.simple('foo]'), findElement.method('foo'));
-  }
-
-  test_prefixedIdentifier_class_staticSetter() async {
-    await assertNoErrorsInCode(r'''
-class A {
-  static set foo(int _) {}
-}
-
-/// [A.foo]
-void f() {}
-''');
-
-    assertElement(findNode.simple('A.foo'), findElement.class_('A'));
-    assertElement(findNode.simple('foo]'), findElement.setter('foo'));
-  }
-
-  test_prefixedIdentifier_extension_instanceGetter() async {
-    await assertNoErrorsInCode(r'''
-extension E on int {
-  int get foo => 0;
-}
-
-/// [E.foo]
-void f() {}
-''');
-
-    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
-    assertElement(findNode.simple('foo]'), findElement.getter('foo'));
-  }
-
-  test_prefixedIdentifier_extension_instanceMethod() async {
-    await assertNoErrorsInCode(r'''
-extension E on int {
-  void foo() {}
-}
-
-/// [E.foo]
-void f() {}
-''');
-
-    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
-    assertElement(findNode.simple('foo]'), findElement.method('foo'));
-  }
-
-  test_prefixedIdentifier_extension_instanceSetter() async {
-    await assertNoErrorsInCode(r'''
-extension E on int {
-  set foo(int _) {}
-}
-
-/// [E.foo]
-void f() {}
-''');
-
-    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
-    assertElement(findNode.simple('foo]'), findElement.setter('foo'));
-  }
-
-  test_prefixedIdentifier_extension_staticGetter() async {
-    await assertNoErrorsInCode(r'''
-extension E on int {
-  static int get foo => 0;
-}
-
-/// [E.foo]
-void f() {}
-''');
-
-    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
-    assertElement(findNode.simple('foo]'), findElement.getter('foo'));
-  }
-
-  test_prefixedIdentifier_extension_staticMethod() async {
-    await assertNoErrorsInCode(r'''
-extension E on int {
-  static void foo() {}
-}
-
-/// [E.foo]
-void f() {}
-''');
-
-    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
-    assertElement(findNode.simple('foo]'), findElement.method('foo'));
-  }
-
-  test_prefixedIdentifier_extension_staticSetter() async {
-    await assertNoErrorsInCode(r'''
-extension E on int {
-  static set foo(int _) {}
-}
-
-/// [E.foo]
-void f() {}
-''');
-
-    assertElement(findNode.simple('E.foo'), findElement.extension_('E'));
-    assertElement(findNode.simple('foo]'), findElement.setter('foo'));
-  }
-
-  test_simpleIdentifier_beforeClass() async {
-    await assertNoErrorsInCode(r'''
-/// [foo]
-class A {
-  foo() {}
-}
-''');
-
-    assertElement(
-      findNode.simple('foo]'),
-      findElement.method('foo'),
-    );
-  }
-
-  test_simpleIdentifier_beforeConstructor() async {
-    await assertNoErrorsInCode(r'''
-class A {
-  /// [p]
-  A(int p);
-}''');
-
-    assertElement(
-      findNode.simple('p]'),
-      findElement.parameter('p'),
-    );
-  }
-
-  test_simpleIdentifier_beforeEnum() async {
-    await assertNoErrorsInCode(r'''
-/// This is the [Samurai] kind.
-enum Samurai {
-  /// Use [int].
-  WITH_SWORD,
-  /// Like [WITH_SWORD], but only without one.
-  WITHOUT_SWORD
-}''');
-
-    assertElement(
-      findNode.simple('Samurai]'),
-      findElement.enum_('Samurai'),
-    );
-    assertElement(
-      findNode.simple('int]'),
-      intElement,
-    );
-    assertElement(
-      findNode.simple('WITH_SWORD]'),
-      findElement.getter('WITH_SWORD'),
-    );
-  }
-
-  test_simpleIdentifier_beforeFunction_blockBody() async {
-    await assertNoErrorsInCode(r'''
-/// [p]
-foo(int p) {}
-''');
-
-    assertElement(
-      findNode.simple('p]'),
-      findElement.parameter('p'),
-    );
-  }
-
-  test_simpleIdentifier_beforeFunction_expressionBody() async {
-    await assertNoErrorsInCode(r'''
-/// [p]
-foo(int p) => null;
-''');
-
-    assertElement(
-      findNode.simple('p]'),
-      findElement.parameter('p'),
-    );
-  }
-
-  test_simpleIdentifier_beforeFunctionTypeAlias() async {
-    await assertNoErrorsInCode(r'''
-/// [p]
-typedef Foo(int p);
-''');
-
-    assertElement(
-      findNode.simple('p]'),
-      findElement.parameter('p'),
-    );
-  }
-
-  test_simpleIdentifier_beforeGenericTypeAlias() async {
-    await assertNoErrorsInCode(r'''
-/// Can resolve [T], [S], and [p].
-typedef Foo<T> = Function<S>(int p);
-''');
-
-    assertElement(
-      findNode.simple('T]'),
-      findElement.typeParameter('T'),
-    );
-    assertElement(findNode.simple('S]'), findElement.typeParameter('S'));
-    assertElement(
-      findNode.simple('p]'),
-      findElement.parameter('p'),
-    );
-  }
-
-  test_simpleIdentifier_beforeGetter() async {
-    await assertNoErrorsInCode(r'''
-/// [int]
-get g => null;
-''');
-
-    assertElement(findNode.simple('int]'), intElement);
-  }
-
-  test_simpleIdentifier_beforeMethod() async {
-    await assertNoErrorsInCode(r'''
-abstract class A {
-  /// [p1]
-  ma(int p1);
-
-  /// [p2]
-  mb(int p2);
-
-  /// [p3] and [p4]
-  mc(int p3, p4());
-
-  /// [p5]
-  md(int p5, {int p6});
-}
-''');
-
-    assertElement(findNode.simple('p1]'), findElement.parameter('p1'));
-    assertElement(findNode.simple('p2]'), findElement.parameter('p2'));
-    assertElement(findNode.simple('p3]'), findElement.parameter('p3'));
-    assertElement(findNode.simple('p4]'), findElement.parameter('p4'));
-    assertElement(findNode.simple('p5]'), findElement.parameter('p5'));
-  }
-
-  test_simpleIdentifier_parameter_functionTyped() async {
+  test_parameter_functionTyped() async {
     await assertNoErrorsInCode(r'''
 /// [bar]
 foo(int bar()) {}
@@ -360,7 +655,7 @@
     );
   }
 
-  test_simpleIdentifier_setter() async {
+  test_setter() async {
     await assertNoErrorsInCode(r'''
 class A {
   /// [x] in A
@@ -379,7 +674,7 @@
     assertElement(findNode.simple('x] in B'), x);
   }
 
-  test_simpleIdentifier_unqualifiedReferenceToNonLocalStaticMember() async {
+  test_unqualifiedReferenceToNonLocalStaticMember() async {
     await assertNoErrorsInCode('''
 class A {
   static void foo() {}
diff --git a/pkg/analyzer/test/src/dart/resolution/context_collection_resolution.dart b/pkg/analyzer/test/src/dart/resolution/context_collection_resolution.dart
index 1b491ac..7d2c061 100644
--- a/pkg/analyzer/test/src/dart/resolution/context_collection_resolution.dart
+++ b/pkg/analyzer/test/src/dart/resolution/context_collection_resolution.dart
@@ -259,6 +259,7 @@
   List<String> get experiments => [
         EnableString.constructor_tearoffs,
         EnableString.named_arguments_anywhere,
+        EnableString.super_parameters,
       ];
 
   /// The path that is not in [workspaceRootPath], contains external packages.
diff --git a/pkg/analyzer/test/src/dart/resolution/super_formal_parameter_test.dart b/pkg/analyzer/test/src/dart/resolution/super_formal_parameter_test.dart
new file mode 100644
index 0000000..6a24380
--- /dev/null
+++ b/pkg/analyzer/test/src/dart/resolution/super_formal_parameter_test.dart
@@ -0,0 +1,130 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analyzer/src/test_utilities/find_element.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import 'context_collection_resolution.dart';
+
+main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(SuperFormalParameterTest);
+  });
+}
+
+@reflectiveTest
+class SuperFormalParameterTest extends PubPackageResolutionTest {
+  test_functionTyped() async {
+    await assertNoErrorsInCode(r'''
+class A {
+  A(Object a);
+}
+
+class B extends A {
+  B(super.a<T>(int b));
+}
+''');
+
+    var B = findElement.unnamedConstructor('B');
+    var element = B.superFormalParameter('a');
+
+    assertElement(
+      findNode.superFormalParameter('super.a'),
+      element,
+    );
+
+    assertElement(
+      findNode.typeParameter('T>'),
+      element.typeParameters[0],
+    );
+
+    assertElement(
+      findNode.simpleFormalParameter('b));'),
+      element.parameters[0],
+    );
+  }
+
+  test_invalid_notConstructor() async {
+    await assertNoErrorsInCode(r'''
+void f(super.a) {}
+''');
+
+    var f = findElement.topFunction('f');
+    var element = f.superFormalParameter('a');
+    assertTypeDynamic(element.type);
+
+    assertElement(
+      findNode.superFormalParameter('super.a'),
+      element,
+    );
+  }
+
+  test_optionalNamed() async {
+    await assertNoErrorsInCode(r'''
+class A {
+  A({int? a});
+}
+
+class B extends A {
+  B({super.a});
+}
+''');
+
+    assertElement(
+      findNode.superFormalParameter('super.a'),
+      findElement.unnamedConstructor('B').superFormalParameter('a'),
+    );
+  }
+
+  test_optionalPositional() async {
+    await assertNoErrorsInCode(r'''
+class A {
+  A([int? a]);
+}
+
+class B extends A {
+  B([super.a]);
+}
+''');
+
+    assertElement(
+      findNode.superFormalParameter('super.a'),
+      findElement.unnamedConstructor('B').superFormalParameter('a'),
+    );
+  }
+
+  test_requiredNamed() async {
+    await assertNoErrorsInCode(r'''
+class A {
+  A({required int a});
+}
+
+class B extends A {
+  B({required super.a});
+}
+''');
+
+    assertElement(
+      findNode.superFormalParameter('super.a'),
+      findElement.unnamedConstructor('B').superFormalParameter('a'),
+    );
+  }
+
+  test_requiredPositional() async {
+    await assertNoErrorsInCode(r'''
+class A {
+  A(int a);
+}
+
+class B extends A {
+  B(super.a);
+}
+''');
+
+    assertElement(
+      findNode.superFormalParameter('super.a'),
+      findElement.unnamedConstructor('B').superFormalParameter('a'),
+    );
+  }
+}
diff --git a/pkg/analyzer/test/src/dart/resolution/test_all.dart b/pkg/analyzer/test/src/dart/resolution/test_all.dart
index 0c72655..759b9e5 100644
--- a/pkg/analyzer/test/src/dart/resolution/test_all.dart
+++ b/pkg/analyzer/test/src/dart/resolution/test_all.dart
@@ -58,6 +58,7 @@
 import 'prefixed_identifier_test.dart' as prefixed_identifier;
 import 'property_access_test.dart' as property_access;
 import 'simple_identifier_test.dart' as simple_identifier;
+import 'super_formal_parameter_test.dart' as super_formal_parameter;
 import 'top_level_variable_test.dart' as top_level_variable;
 import 'top_type_inference_test.dart' as top_type_inference;
 import 'try_statement_test.dart' as try_statement;
@@ -119,6 +120,7 @@
     prefixed_identifier.main();
     property_access.main();
     simple_identifier.main();
+    super_formal_parameter.main();
     top_level_variable.main();
     top_type_inference.main();
     try_statement.main();
diff --git a/pkg/analyzer/test/src/diagnostics/body_might_complete_normally_nullable_test.dart b/pkg/analyzer/test/src/diagnostics/body_might_complete_normally_nullable_test.dart
new file mode 100644
index 0000000..3925f45
--- /dev/null
+++ b/pkg/analyzer/test/src/diagnostics/body_might_complete_normally_nullable_test.dart
@@ -0,0 +1,74 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analyzer/src/error/codes.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import '../dart/resolution/context_collection_resolution.dart';
+
+main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(BodyMightCompleteNormallyNullableTest);
+  });
+}
+
+@reflectiveTest
+class BodyMightCompleteNormallyNullableTest extends PubPackageResolutionTest {
+  test_function_async_block_futureOrIntQuestion() async {
+    await assertErrorsInCode('''
+import 'dart:async';
+FutureOr<int?> f(Future f) async {}
+''', [
+      error(HintCode.BODY_MIGHT_COMPLETE_NORMALLY_NULLABLE, 36, 1),
+    ]);
+  }
+
+  test_function_async_block_futureOrVoid() async {
+    await assertNoErrorsInCode('''
+import 'dart:async';
+FutureOr<void> f(Future f) async {}
+''');
+  }
+
+  test_function_async_block_void() async {
+    await assertNoErrorsInCode('''
+import 'dart:async';
+void f(Future f) async {}
+''');
+  }
+
+  test_function_sync_block_dynamic() async {
+    await assertNoErrorsInCode('''
+dynamic f() {}
+''');
+  }
+
+  test_function_sync_block_intQuestion() async {
+    await assertErrorsInCode('''
+int? f() {}
+''', [
+      error(HintCode.BODY_MIGHT_COMPLETE_NORMALLY_NULLABLE, 5, 1),
+    ]);
+  }
+
+  test_function_sync_block_intQuestion_definiteReturn() async {
+    await assertNoErrorsInCode('''
+int? f() {
+  return null;
+}
+''');
+  }
+
+  test_function_sync_block_Null() async {
+    await assertNoErrorsInCode('''
+Null f() {}
+''');
+  }
+
+  test_function_sync_block_void() async {
+    await assertNoErrorsInCode('''
+void f() {}
+''');
+  }
+}
diff --git a/pkg/analyzer/test/src/diagnostics/body_might_complete_normally_test.dart b/pkg/analyzer/test/src/diagnostics/body_might_complete_normally_test.dart
index e223720..973910e 100644
--- a/pkg/analyzer/test/src/diagnostics/body_might_complete_normally_test.dart
+++ b/pkg/analyzer/test/src/diagnostics/body_might_complete_normally_test.dart
@@ -222,16 +222,6 @@
 ''');
   }
 
-  test_functionExpression_nullable_blockBody() async {
-    await assertNoErrorsInCode(r'''
-main() {
-  int? Function() foo = () {
-  };
-  foo;
-}
-''');
-  }
-
   test_generativeConstructor_blockBody() async {
     await assertNoErrorsInCode(r'''
 class A {
@@ -350,14 +340,6 @@
 ''');
   }
 
-  test_method_nullable_blockBody() async {
-    await assertNoErrorsInCode(r'''
-class A {
-  int? foo() {}
-}
-''');
-  }
-
   test_method_nullable_blockBody_return() async {
     await assertNoErrorsInCode(r'''
 class A {
diff --git a/pkg/analyzer/test/src/diagnostics/const_constructor_param_type_mismatch_test.dart b/pkg/analyzer/test/src/diagnostics/const_constructor_param_type_mismatch_test.dart
index f9bcac1..cdd3c81 100644
--- a/pkg/analyzer/test/src/diagnostics/const_constructor_param_type_mismatch_test.dart
+++ b/pkg/analyzer/test/src/diagnostics/const_constructor_param_type_mismatch_test.dart
@@ -288,6 +288,20 @@
       error(CompileTimeErrorCode.ARGUMENT_TYPE_NOT_ASSIGNABLE, 46, 5),
     ]);
   }
+
+  test_unknown_conditionalExpression_unknownCondition() async {
+    await assertNoErrorsInCode(r'''
+const bool kIsWeb = identical(0, 0.0);
+
+void f() {
+  const A(kIsWeb ? 0 : 1);
+}
+
+class A {
+  const A(int _);
+}
+''');
+  }
 }
 
 @reflectiveTest
diff --git a/pkg/analyzer/test/src/diagnostics/illegal_async_return_type_test.dart b/pkg/analyzer/test/src/diagnostics/illegal_async_return_type_test.dart
index 01e30f0..1d56d74 100644
--- a/pkg/analyzer/test/src/diagnostics/illegal_async_return_type_test.dart
+++ b/pkg/analyzer/test/src/diagnostics/illegal_async_return_type_test.dart
@@ -17,7 +17,9 @@
 class IllegalAsyncReturnTypeTest extends PubPackageResolutionTest {
   test_function_nonFuture() async {
     await assertErrorsInCode('''
-int f() async {}
+int f() async {
+  return 1;
+}
 ''', [
       error(CompileTimeErrorCode.ILLEGAL_ASYNC_RETURN_TYPE, 0, 3),
     ]);
@@ -53,7 +55,9 @@
   test_method_nonFuture() async {
     await assertErrorsInCode('''
 class C {
-  int m() async {}
+  int m() async {
+    return 1;
+  }
 }
 ''', [
       error(CompileTimeErrorCode.ILLEGAL_ASYNC_RETURN_TYPE, 12, 3),
diff --git a/pkg/analyzer/test/src/diagnostics/missing_return_test.dart b/pkg/analyzer/test/src/diagnostics/missing_return_test.dart
index 7fbed0b..9f75275 100644
--- a/pkg/analyzer/test/src/diagnostics/missing_return_test.dart
+++ b/pkg/analyzer/test/src/diagnostics/missing_return_test.dart
@@ -140,7 +140,7 @@
   }
 
   test_functionExpression_sync_dynamic() async {
-    await assertNoErrorsInCode(r'''
+    await assertNoErrorsInCode('''
 Function() f = () {};
 ''');
   }
@@ -153,7 +153,7 @@
 
   test_localFunction_sync_dynamic() async {
     await assertNoErrorsInCode(r'''
-main() {
+void foo() {
   f() {}
   f;
 }
@@ -217,7 +217,26 @@
 
 @reflectiveTest
 class MissingReturnWithNullSafetyTest extends PubPackageResolutionTest {
-  test_returnNever() async {
+  test_function_async_block_futureOrVoid() async {
+    await assertNoErrorsInCode('''
+import 'dart:async';
+FutureOr<void> f() async {}
+''');
+  }
+
+  test_function_async_block_void() async {
+    await assertNoErrorsInCode('''
+void f() async {}
+''');
+  }
+
+  test_function_sync_block_dynamic() async {
+    await assertNoErrorsInCode('''
+dynamic f() {}
+''');
+  }
+
+  test_function_sync_block_Never() async {
     newFile('$testPackageLibPath/a.dart', content: r'''
 Never foo() {
   throw 0;
@@ -232,4 +251,16 @@
 }
 ''');
   }
+
+  test_function_sync_block_Null() async {
+    await assertNoErrorsInCode('''
+Null f() {}
+''');
+  }
+
+  test_function_sync_block_void() async {
+    await assertNoErrorsInCode('''
+void f() {}
+''');
+  }
 }
diff --git a/pkg/analyzer/test/src/diagnostics/subtype_of_struct_class_test.dart b/pkg/analyzer/test/src/diagnostics/subtype_of_struct_class_test.dart
index 969c1be..0d24687 100644
--- a/pkg/analyzer/test/src/diagnostics/subtype_of_struct_class_test.dart
+++ b/pkg/analyzer/test/src/diagnostics/subtype_of_struct_class_test.dart
@@ -45,6 +45,23 @@
 
 @reflectiveTest
 class SubtypeOfStructClassInImplementsTest extends PubPackageResolutionTest {
+  test_implements_abi_specific_int() async {
+    await assertErrorsInCode(r'''
+import 'dart:ffi';
+@AbiSpecificIntegerMapping({
+  Abi.androidArm: Uint32(),
+})
+class AbiSpecificInteger1 extends AbiSpecificInteger {
+  const AbiSpecificInteger1();
+}
+class AbiSpecificInteger4 implements AbiSpecificInteger1 {
+  const AbiSpecificInteger4();
+}
+''', [
+      error(FfiCode.SUBTYPE_OF_STRUCT_CLASS_IN_IMPLEMENTS, 204, 19),
+    ]);
+  }
+
   test_implements_struct() async {
     await assertErrorsInCode(r'''
 import 'dart:ffi';
diff --git a/pkg/analyzer/test/src/diagnostics/test_all.dart b/pkg/analyzer/test/src/diagnostics/test_all.dart
index 4456cef..485fb55 100644
--- a/pkg/analyzer/test/src/diagnostics/test_all.dart
+++ b/pkg/analyzer/test/src/diagnostics/test_all.dart
@@ -41,6 +41,8 @@
     as await_in_late_local_variable_initializer;
 import 'await_in_wrong_context_test.dart' as await_in_wrong_context;
 import 'binary_operator_written_out_test.dart' as binary_operator_written_out;
+import 'body_might_complete_normally_nullable_test.dart'
+    as body_might_complete_normally_nullable;
 import 'body_might_complete_normally_test.dart' as body_might_complete_normally;
 import 'built_in_identifier_as_extension_name_test.dart'
     as built_in_as_extension_name;
@@ -751,6 +753,7 @@
     await_in_late_local_variable_initializer.main();
     await_in_wrong_context.main();
     binary_operator_written_out.main();
+    body_might_complete_normally_nullable.main();
     body_might_complete_normally.main();
     built_in_as_extension_name.main();
     built_in_as_prefix_name.main();
diff --git a/pkg/analyzer/test/src/diagnostics/unused_element_test.dart b/pkg/analyzer/test/src/diagnostics/unused_element_test.dart
index b2827a4..c377ca0 100644
--- a/pkg/analyzer/test/src/diagnostics/unused_element_test.dart
+++ b/pkg/analyzer/test/src/diagnostics/unused_element_test.dart
@@ -3,6 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:analyzer/src/dart/error/hint_codes.dart';
+import 'package:test/expect.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
 import '../dart/resolution/context_collection_resolution.dart';
@@ -1699,6 +1700,37 @@
 
 @reflectiveTest
 class UnusedElementWithNullSafetyTest extends PubPackageResolutionTest {
+  test_optionalParameter_isUsed_genericConstructor() async {
+    await assertNoErrorsInCode('''
+class C<T> {
+  C._([int? x]);
+}
+void foo() {
+  C._(7);
+}
+''');
+  }
+
+  test_optionalParameter_isUsed_genericFunction() async {
+    await assertNoErrorsInCode('''
+void _f<T>([int? x]) {}
+void foo() {
+  _f(7);
+}
+''');
+  }
+
+  test_optionalParameter_isUsed_genericMethod() async {
+    await assertNoErrorsInCode('''
+class C {
+  void _m<T>([int? x]) {}
+}
+void foo() {
+  C()._m(7);
+}
+''');
+  }
+
   test_optionalParameter_isUsed_overrideRequiredNamed() async {
     await assertNoErrorsInCode(r'''
 class A {
@@ -1711,6 +1743,49 @@
 ''');
   }
 
+  @FailingTest(issue: 'https://github.com/dart-lang/sdk/issues/47839')
+  test_optionalParameter_notUsed_genericConstructor() async {
+    // TODO(srawlins): Change to assertErrorsInCode when this is fixed.
+    addTestFile('''
+class C<T> {
+  C._([int? x]);
+}
+void foo() {
+  C._();
+}
+''');
+    await resolveTestFile();
+    expect(result.errors, isNotEmpty);
+  }
+
+  @FailingTest(issue: 'https://github.com/dart-lang/sdk/issues/47839')
+  test_optionalParameter_notUsed_genericFunction() async {
+    // TODO(srawlins): Change to assertErrorsInCode when this is fixed.
+    addTestFile('''
+void _f<T>([int? x]) {}
+void foo() {
+  _f();
+}
+''');
+    await resolveTestFile();
+    expect(result.errors, isNotEmpty);
+  }
+
+  @FailingTest(issue: 'https://github.com/dart-lang/sdk/issues/47839')
+  test_optionalParameter_notUsed_genericMethod() async {
+    // TODO(srawlins): Change to assertErrorsInCode when this is fixed.
+    addTestFile('''
+class C {
+  void _m<T>([int? x]) {}
+}
+void foo() {
+  C()._m();
+}
+''');
+    await resolveTestFile();
+    expect(result.errors, isNotEmpty);
+  }
+
   test_typeAlias_interfaceType_isUsed_typeName_isExpression() async {
     await assertNoErrorsInCode(r'''
 typedef _A = List<int>;
diff --git a/pkg/analyzer/test/src/lint/pub_test.dart b/pkg/analyzer/test/src/lint/pub_test.dart
index db3a2d0..b5fbe2a 100644
--- a/pkg/analyzer/test/src/lint/pub_test.dart
+++ b/pkg/analyzer/test/src/lint/pub_test.dart
@@ -48,6 +48,8 @@
 dev_dependencies:
   markdown: '>=0.7.1+2 <0.8.0'
   unittest: '>=0.11.0 <0.12.0'
+  kittens2:
+    git: git://github.com/munificent/kittens2.git
 dependency_overrides:
   foo: 1.2.0
 repository: https://github.com/dart-lang/linter
@@ -148,6 +150,14 @@
         testValue(
             'url', git.url, equals('git://github.com/munificent/kittens.git'));
       });
+
+      group('git (short form)', () {
+        PSDependency dep = findDependency(ps.devDependencies, name: 'kittens2');
+        PSGitRepo git = dep.git!;
+        test('ref', () => expect(git.ref, isNull));
+        testValue(
+            'url', git.url, equals('git://github.com/munificent/kittens2.git'));
+      });
     });
 //    group('visiting', () {
 //      test('smoke', () {
diff --git a/pkg/analyzer/test/src/summary/element_text.dart b/pkg/analyzer/test/src/summary/element_text.dart
index 96d9eb1..4fb0b3a 100644
--- a/pkg/analyzer/test/src/summary/element_text.dart
+++ b/pkg/analyzer/test/src/summary/element_text.dart
@@ -355,6 +355,19 @@
   void _writeConstructorElement(ConstructorElement e) {
     e as ConstructorElementImpl;
 
+    // Check that the reference exists, and filled with the element.
+    var reference = e.reference;
+    if (reference == null) {
+      fail('Every constructor must have a reference.');
+    } else {
+      var classReference = reference.parent!.parent!;
+      // We need this `if` for duplicate declarations.
+      // The reference might be filled by another declaration.
+      if (identical(classReference.element, e.enclosingElement)) {
+        expect(reference.element, same(e));
+      }
+    }
+
     _writeIndentedLine(() {
       _writeIf(e.isSynthetic, 'synthetic ');
       _writeIf(e.isExternal, 'external ');
@@ -385,6 +398,13 @@
         _writeNode,
       );
 
+      var superConstructor = e.superConstructor;
+      if (superConstructor != null) {
+        if (!superConstructor.enclosingElement.isDartCoreObject) {
+          _writeElementReference('superConstructor', superConstructor);
+        }
+      }
+
       var redirectedConstructor = e.redirectedConstructor;
       if (redirectedConstructor != null) {
         _writeElementReference('redirectedConstructor', redirectedConstructor);
@@ -625,7 +645,7 @@
       } else if (e.isOptionalPositional) {
         buffer.write('optionalPositional ');
       } else if (e.isRequiredNamed) {
-        buffer.write('requiredName ');
+        buffer.write('requiredNamed ');
       } else if (e.isOptionalNamed) {
         buffer.write('optionalNamed ');
       }
@@ -636,6 +656,8 @@
 
       if (e is FieldFormalParameterElement) {
         buffer.write('this.');
+      } else if (e is SuperFormalParameterElement) {
+        buffer.write('super.');
       }
 
       _writeName(e);
@@ -649,6 +671,7 @@
       _writeParameterElements(e.parameters);
       _writeConstantInitializer(e);
       _writeNonSyntheticElement(e);
+      _writeSuperConstructorParameter(e);
     });
   }
 
@@ -756,6 +779,17 @@
     });
   }
 
+  void _writeSuperConstructorParameter(ParameterElement e) {
+    if (e is SuperFormalParameterElement) {
+      var superParameter = e.superConstructorParameter;
+      if (superParameter != null) {
+        _writeElementReference('superConstructorParameter', superParameter);
+      } else {
+        _writelnWithIndent('superConstructorParameter: <null>');
+      }
+    }
+  }
+
   void _writeType(DartType type, {String? name}) {
     var typeStr = _typeStr(type);
     if (name != null) {
diff --git a/pkg/analyzer/test/src/summary/in_summary_source_test.dart b/pkg/analyzer/test/src/summary/in_summary_source_test.dart
index 2e8ef04..0587667 100644
--- a/pkg/analyzer/test/src/summary/in_summary_source_test.dart
+++ b/pkg/analyzer/test/src/summary/in_summary_source_test.dart
@@ -2,7 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'package:analyzer/file_system/physical_file_system.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/summary/package_bundle_reader.dart';
 import 'package:test/test.dart';
@@ -19,12 +18,12 @@
   test_InSummarySource() {
     var sourceFactory = SourceFactory([
       InSummaryUriResolver(
-          PhysicalResourceProvider.INSTANCE,
-          MockSummaryDataStore.fake({
-            'package:foo/foo.dart': 'foo.sum',
-            'package:foo/src/foo_impl.dart': 'foo.sum',
-            'package:bar/baz.dart': 'bar.sum',
-          }))
+        MockSummaryDataStore.fake({
+          'package:foo/foo.dart': 'foo.sum',
+          'package:foo/src/foo_impl.dart': 'foo.sum',
+          'package:bar/baz.dart': 'bar.sum',
+        }),
+      )
     ]);
 
     var source =
diff --git a/pkg/analyzer/test/src/summary/resynthesize_ast2_test.dart b/pkg/analyzer/test/src/summary/resynthesize_ast2_test.dart
index 6378283..3c1a267 100644
--- a/pkg/analyzer/test/src/summary/resynthesize_ast2_test.dart
+++ b/pkg/analyzer/test/src/summary/resynthesize_ast2_test.dart
@@ -230,7 +230,7 @@
       }
 
       var absoluteUri = resolveRelativeUri(source.uri, relativeUri);
-      var rewrittenUri = rewriteFileToPackageUri(sourceFactory, absoluteUri);
+      var rewrittenUri = rewriteToCanonicalUri(sourceFactory, absoluteUri);
       if (rewrittenUri == null) {
         return;
       }
diff --git a/pkg/analyzer/test/src/summary/resynthesize_common.dart b/pkg/analyzer/test/src/summary/resynthesize_common.dart
index bdfa95c..3d50b66 100644
--- a/pkg/analyzer/test/src/summary/resynthesize_common.dart
+++ b/pkg/analyzer/test/src/summary/resynthesize_common.dart
@@ -97,9 +97,10 @@
   );
 
   static final FeatureSet latestWithExperiments = FeatureSet.fromEnableFlags2(
-    sdkLanguageVersion: Version.parse('2.15.0'),
+    sdkLanguageVersion: Version.parse('2.16.0'),
     flags: [
       EnableString.constructor_tearoffs,
+      EnableString.super_parameters,
     ],
   );
 }
@@ -119,764 +120,6 @@
 ''');
   }
 
-  test_class_alias() async {
-    var library = await checkLibrary('''
-class C = D with E, F, G;
-class D {}
-class E {}
-class F {}
-class G {}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class alias C @6
-        supertype: D
-        mixins
-          E
-          F
-          G
-        constructors
-          synthetic @-1
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                staticElement: self::@class::D::@constructor::•
-                superKeyword: super @0
-      class D @32
-        constructors
-          synthetic @-1
-      class E @43
-        constructors
-          synthetic @-1
-      class F @54
-        constructors
-          synthetic @-1
-      class G @65
-        constructors
-          synthetic @-1
-''');
-  }
-
-  test_class_alias_abstract() async {
-    var library = await checkLibrary('''
-abstract class C = D with E;
-class D {}
-class E {}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      abstract class alias C @15
-        supertype: D
-        mixins
-          E
-        constructors
-          synthetic @-1
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                staticElement: self::@class::D::@constructor::•
-                superKeyword: super @0
-      class D @35
-        constructors
-          synthetic @-1
-      class E @46
-        constructors
-          synthetic @-1
-''');
-  }
-
-  test_class_alias_documented() async {
-    var library = await checkLibrary('''
-/**
- * Docs
- */
-class C = D with E;
-
-class D {}
-class E {}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class alias C @22
-        documentationComment: /**\n * Docs\n */
-        supertype: D
-        mixins
-          E
-        constructors
-          synthetic @-1
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                staticElement: self::@class::D::@constructor::•
-                superKeyword: super @0
-      class D @43
-        constructors
-          synthetic @-1
-      class E @54
-        constructors
-          synthetic @-1
-''');
-  }
-
-  test_class_alias_documented_tripleSlash() async {
-    var library = await checkLibrary('''
-/// aaa
-/// b
-/// cc
-class C = D with E;
-
-class D {}
-class E {}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class alias C @27
-        documentationComment: /// aaa\n/// b\n/// cc
-        supertype: D
-        mixins
-          E
-        constructors
-          synthetic @-1
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                staticElement: self::@class::D::@constructor::•
-                superKeyword: super @0
-      class D @48
-        constructors
-          synthetic @-1
-      class E @59
-        constructors
-          synthetic @-1
-''');
-  }
-
-  test_class_alias_documented_withLeadingNonDocumentation() async {
-    var library = await checkLibrary('''
-// Extra comment so doc comment offset != 0
-/**
- * Docs
- */
-class C = D with E;
-
-class D {}
-class E {}''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class alias C @66
-        documentationComment: /**\n * Docs\n */
-        supertype: D
-        mixins
-          E
-        constructors
-          synthetic @-1
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                staticElement: self::@class::D::@constructor::•
-                superKeyword: super @0
-      class D @87
-        constructors
-          synthetic @-1
-      class E @98
-        constructors
-          synthetic @-1
-''');
-  }
-
-  test_class_alias_generic() async {
-    var library = await checkLibrary('''
-class Z = A with B<int>, C<double>;
-class A {}
-class B<B1> {}
-class C<C1> {}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class alias Z @6
-        supertype: A
-        mixins
-          B<int>
-          C<double>
-        constructors
-          synthetic @-1
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                staticElement: self::@class::A::@constructor::•
-                superKeyword: super @0
-      class A @42
-        constructors
-          synthetic @-1
-      class B @53
-        typeParameters
-          covariant B1 @55
-            defaultType: dynamic
-        constructors
-          synthetic @-1
-      class C @68
-        typeParameters
-          covariant C1 @70
-            defaultType: dynamic
-        constructors
-          synthetic @-1
-''');
-  }
-
-  test_class_alias_notSimplyBounded_self() async {
-    var library = await checkLibrary('''
-class C<T extends C> = D with E;
-class D {}
-class E {}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      notSimplyBounded class alias C @6
-        typeParameters
-          covariant T @8
-            bound: C<dynamic>
-            defaultType: dynamic
-        supertype: D
-        mixins
-          E
-        constructors
-          synthetic @-1
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                staticElement: self::@class::D::@constructor::•
-                superKeyword: super @0
-      class D @39
-        constructors
-          synthetic @-1
-      class E @50
-        constructors
-          synthetic @-1
-''');
-  }
-
-  test_class_alias_notSimplyBounded_simple_no_type_parameter_bound() async {
-    // If no bounds are specified, then the class is simply bounded by syntax
-    // alone, so there is no reason to assign it a slot.
-    var library = await checkLibrary('''
-class C<T> = D with E;
-class D {}
-class E {}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class alias C @6
-        typeParameters
-          covariant T @8
-            defaultType: dynamic
-        supertype: D
-        mixins
-          E
-        constructors
-          synthetic @-1
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                staticElement: self::@class::D::@constructor::•
-                superKeyword: super @0
-      class D @29
-        constructors
-          synthetic @-1
-      class E @40
-        constructors
-          synthetic @-1
-''');
-  }
-
-  test_class_alias_notSimplyBounded_simple_non_generic() async {
-    // If no type parameters are specified, then the class is simply bounded, so
-    // there is no reason to assign it a slot.
-    var library = await checkLibrary('''
-class C = D with E;
-class D {}
-class E {}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class alias C @6
-        supertype: D
-        mixins
-          E
-        constructors
-          synthetic @-1
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                staticElement: self::@class::D::@constructor::•
-                superKeyword: super @0
-      class D @26
-        constructors
-          synthetic @-1
-      class E @37
-        constructors
-          synthetic @-1
-''');
-  }
-
-  test_class_alias_with_const_constructors() async {
-    testFile = convertPath('/home/test/lib/test.dart');
-    addLibrarySource('/home/test/lib/a.dart', r'''
-class Base {
-  const Base._priv();
-  const Base();
-  const Base.named();
-}
-''');
-    var library = await checkLibrary('''
-import "a.dart";
-class M {}
-class MixinApp = Base with M;
-''');
-    checkElementText(library, r'''
-library
-  imports
-    package:test/a.dart
-  definingUnit
-    classes
-      class M @23
-        constructors
-          synthetic @-1
-      class alias MixinApp @34
-        supertype: Base
-        mixins
-          M
-        constructors
-          synthetic const @-1
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                staticElement: package:test/a.dart::@class::Base::@constructor::•
-                superKeyword: super @0
-          synthetic const named @-1
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                constructorName: SimpleIdentifier
-                  staticElement: package:test/a.dart::@class::Base::@constructor::named
-                  staticType: null
-                  token: named @-1
-                period: . @0
-                staticElement: package:test/a.dart::@class::Base::@constructor::named
-                superKeyword: super @0
-''');
-  }
-
-  test_class_alias_with_forwarding_constructors() async {
-    testFile = convertPath('/home/test/lib/test.dart');
-    addLibrarySource('/home/test/lib/a.dart', r'''
-class Base {
-  bool x = true;
-  Base._priv();
-  Base();
-  Base.noArgs();
-  Base.requiredArg(x);
-  Base.positionalArg([bool x = true]);
-  Base.positionalArg2([this.x = true]);
-  Base.namedArg({int x = 42});
-  Base.namedArg2({this.x = true});
-  factory Base.fact() => Base();
-  factory Base.fact2() = Base.noArgs;
-}
-''');
-    var library = await checkLibrary('''
-import "a.dart";
-class M {}
-class MixinApp = Base with M;
-''');
-    checkElementText(library, r'''
-library
-  imports
-    package:test/a.dart
-  definingUnit
-    classes
-      class M @23
-        constructors
-          synthetic @-1
-      class alias MixinApp @34
-        supertype: Base
-        mixins
-          M
-        constructors
-          synthetic @-1
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                staticElement: package:test/a.dart::@class::Base::@constructor::•
-                superKeyword: super @0
-          synthetic noArgs @-1
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                constructorName: SimpleIdentifier
-                  staticElement: package:test/a.dart::@class::Base::@constructor::noArgs
-                  staticType: null
-                  token: noArgs @-1
-                period: . @0
-                staticElement: package:test/a.dart::@class::Base::@constructor::noArgs
-                superKeyword: super @0
-          synthetic requiredArg @-1
-            parameters
-              requiredPositional x @-1
-                type: dynamic
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    SimpleIdentifier
-                      staticElement: x@-1
-                      staticType: dynamic
-                      token: x @-1
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                constructorName: SimpleIdentifier
-                  staticElement: package:test/a.dart::@class::Base::@constructor::requiredArg
-                  staticType: null
-                  token: requiredArg @-1
-                period: . @0
-                staticElement: package:test/a.dart::@class::Base::@constructor::requiredArg
-                superKeyword: super @0
-          synthetic positionalArg @-1
-            parameters
-              optionalPositional x @-1
-                type: bool
-                constantInitializer
-                  BooleanLiteral
-                    literal: true @127
-                    staticType: bool
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    SimpleIdentifier
-                      staticElement: x@-1
-                      staticType: bool
-                      token: x @-1
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                constructorName: SimpleIdentifier
-                  staticElement: package:test/a.dart::@class::Base::@constructor::positionalArg
-                  staticType: null
-                  token: positionalArg @-1
-                period: . @0
-                staticElement: package:test/a.dart::@class::Base::@constructor::positionalArg
-                superKeyword: super @0
-          synthetic positionalArg2 @-1
-            parameters
-              optionalPositional final x @-1
-                type: bool
-                constantInitializer
-                  BooleanLiteral
-                    literal: true @167
-                    staticType: bool
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    SimpleIdentifier
-                      staticElement: x@-1
-                      staticType: bool
-                      token: x @-1
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                constructorName: SimpleIdentifier
-                  staticElement: package:test/a.dart::@class::Base::@constructor::positionalArg2
-                  staticType: null
-                  token: positionalArg2 @-1
-                period: . @0
-                staticElement: package:test/a.dart::@class::Base::@constructor::positionalArg2
-                superKeyword: super @0
-          synthetic namedArg @-1
-            parameters
-              optionalNamed x @-1
-                type: int
-                constantInitializer
-                  IntegerLiteral
-                    literal: 42 @200
-                    staticType: int
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    SimpleIdentifier
-                      staticElement: x@-1
-                      staticType: int
-                      token: x @-1
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                constructorName: SimpleIdentifier
-                  staticElement: package:test/a.dart::@class::Base::@constructor::namedArg
-                  staticType: null
-                  token: namedArg @-1
-                period: . @0
-                staticElement: package:test/a.dart::@class::Base::@constructor::namedArg
-                superKeyword: super @0
-          synthetic namedArg2 @-1
-            parameters
-              optionalNamed final x @-1
-                type: bool
-                constantInitializer
-                  BooleanLiteral
-                    literal: true @233
-                    staticType: bool
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    SimpleIdentifier
-                      staticElement: x@-1
-                      staticType: bool
-                      token: x @-1
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                constructorName: SimpleIdentifier
-                  staticElement: package:test/a.dart::@class::Base::@constructor::namedArg2
-                  staticType: null
-                  token: namedArg2 @-1
-                period: . @0
-                staticElement: package:test/a.dart::@class::Base::@constructor::namedArg2
-                superKeyword: super @0
-''');
-  }
-
-  test_class_alias_with_forwarding_constructors_type_substitution() async {
-    var library = await checkLibrary('''
-class Base<T> {
-  Base.ctor(T t, List<T> l);
-}
-class M {}
-class MixinApp = Base with M;
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class Base @6
-        typeParameters
-          covariant T @11
-            defaultType: dynamic
-        constructors
-          ctor @23
-            periodOffset: 22
-            nameEnd: 27
-            parameters
-              requiredPositional t @30
-                type: T
-              requiredPositional l @41
-                type: List<T>
-      class M @53
-        constructors
-          synthetic @-1
-      class alias MixinApp @64
-        supertype: Base<dynamic>
-        mixins
-          M
-        constructors
-          synthetic ctor @-1
-            parameters
-              requiredPositional t @-1
-                type: dynamic
-              requiredPositional l @-1
-                type: List<dynamic>
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    SimpleIdentifier
-                      staticElement: t@-1
-                      staticType: dynamic
-                      token: t @-1
-                    SimpleIdentifier
-                      staticElement: l@-1
-                      staticType: List<dynamic>
-                      token: l @-1
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                constructorName: SimpleIdentifier
-                  staticElement: self::@class::Base::@constructor::ctor
-                  staticType: null
-                  token: ctor @-1
-                period: . @0
-                staticElement: self::@class::Base::@constructor::ctor
-                superKeyword: super @0
-''');
-  }
-
-  test_class_alias_with_forwarding_constructors_type_substitution_complex() async {
-    var library = await checkLibrary('''
-class Base<T> {
-  Base.ctor(T t, List<T> l);
-}
-class M {}
-class MixinApp<U> = Base<List<U>> with M;
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class Base @6
-        typeParameters
-          covariant T @11
-            defaultType: dynamic
-        constructors
-          ctor @23
-            periodOffset: 22
-            nameEnd: 27
-            parameters
-              requiredPositional t @30
-                type: T
-              requiredPositional l @41
-                type: List<T>
-      class M @53
-        constructors
-          synthetic @-1
-      class alias MixinApp @64
-        typeParameters
-          covariant U @73
-            defaultType: dynamic
-        supertype: Base<List<U>>
-        mixins
-          M
-        constructors
-          synthetic ctor @-1
-            parameters
-              requiredPositional t @-1
-                type: List<U>
-              requiredPositional l @-1
-                type: List<List<U>>
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    SimpleIdentifier
-                      staticElement: t@-1
-                      staticType: List<U>
-                      token: t @-1
-                    SimpleIdentifier
-                      staticElement: l@-1
-                      staticType: List<List<U>>
-                      token: l @-1
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                constructorName: SimpleIdentifier
-                  staticElement: self::@class::Base::@constructor::ctor
-                  staticType: null
-                  token: ctor @-1
-                period: . @0
-                staticElement: self::@class::Base::@constructor::ctor
-                superKeyword: super @0
-''');
-  }
-
-  test_class_alias_with_mixin_members() async {
-    var library = await checkLibrary('''
-class C = D with E;
-class D {}
-class E {
-  int get a => null;
-  void set b(int i) {}
-  void f() {}
-  int x;
-}''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class alias C @6
-        supertype: D
-        mixins
-          E
-        constructors
-          synthetic @-1
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  leftParenthesis: ( @0
-                  rightParenthesis: ) @0
-                staticElement: self::@class::D::@constructor::•
-                superKeyword: super @0
-      class D @26
-        constructors
-          synthetic @-1
-      class E @37
-        fields
-          x @105
-            type: int
-          synthetic a @-1
-            type: int
-          synthetic b @-1
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get x @-1
-            returnType: int
-          synthetic set x @-1
-            parameters
-              requiredPositional _x @-1
-                type: int
-            returnType: void
-          get a @51
-            returnType: int
-          set b @73
-            parameters
-              requiredPositional i @79
-                type: int
-            returnType: void
-        methods
-          f @92
-            returnType: void
-''');
-  }
-
   test_class_constructor_const() async {
     var library = await checkLibrary('class C { const C(); }');
     checkElementText(library, r'''
@@ -901,6 +144,25 @@
 ''');
   }
 
+  test_class_constructor_documented() async {
+    var library = await checkLibrary('''
+class C {
+  /**
+   * Docs
+   */
+  C();
+}''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          @34
+            documentationComment: /**\n   * Docs\n   */
+''');
+  }
+
   test_class_constructor_explicit_named() async {
     var library = await checkLibrary('class C { C.foo(); }');
     checkElementText(library, r'''
@@ -1492,6 +754,1022 @@
 ''');
   }
 
+  test_class_constructor_initializers_assertInvocation() async {
+    var library = await checkLibrary('''
+class C {
+  const C(int x) : assert(x >= 42);
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          const @18
+            parameters
+              requiredPositional x @24
+                type: int
+            constantInitializers
+              AssertInitializer
+                assertKeyword: assert @29
+                condition: BinaryExpression
+                  leftOperand: SimpleIdentifier
+                    staticElement: x@24
+                    staticType: int
+                    token: x @36
+                  operator: >= @38
+                  rightOperand: IntegerLiteral
+                    literal: 42 @41
+                    staticType: int
+                  staticElement: dart:core::@class::num::@method::>=
+                  staticInvokeType: bool Function(num)
+                  staticType: bool
+                leftParenthesis: ( @35
+                rightParenthesis: ) @43
+''');
+  }
+
+  test_class_constructor_initializers_assertInvocation_message() async {
+    var library = await checkLibrary('''
+class C {
+  const C(int x) : assert(x >= 42, 'foo');
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          const @18
+            parameters
+              requiredPositional x @24
+                type: int
+            constantInitializers
+              AssertInitializer
+                assertKeyword: assert @29
+                condition: BinaryExpression
+                  leftOperand: SimpleIdentifier
+                    staticElement: x@24
+                    staticType: int
+                    token: x @36
+                  operator: >= @38
+                  rightOperand: IntegerLiteral
+                    literal: 42 @41
+                    staticType: int
+                  staticElement: dart:core::@class::num::@method::>=
+                  staticInvokeType: bool Function(num)
+                  staticType: bool
+                leftParenthesis: ( @35
+                message: SimpleStringLiteral
+                  literal: 'foo' @45
+                rightParenthesis: ) @50
+''');
+  }
+
+  test_class_constructor_initializers_field() async {
+    var library = await checkLibrary('''
+class C {
+  final x;
+  const C() : x = 42;
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          final x @18
+            type: dynamic
+        constructors
+          const @29
+            constantInitializers
+              ConstructorFieldInitializer
+                equals: = @37
+                expression: IntegerLiteral
+                  literal: 42 @39
+                  staticType: int
+                fieldName: SimpleIdentifier
+                  staticElement: self::@class::C::@field::x
+                  staticType: null
+                  token: x @35
+        accessors
+          synthetic get x @-1
+            returnType: dynamic
+''');
+  }
+
+  test_class_constructor_initializers_field_notConst() async {
+    var library = await checkLibrary('''
+class C {
+  final x;
+  const C() : x = foo();
+}
+int foo() => 42;
+''', allowErrors: true);
+    // It is OK to keep non-constant initializers.
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          final x @18
+            type: dynamic
+        constructors
+          const @29
+            constantInitializers
+              ConstructorFieldInitializer
+                equals: = @37
+                expression: MethodInvocation
+                  argumentList: ArgumentList
+                    leftParenthesis: ( @42
+                    rightParenthesis: ) @43
+                  methodName: SimpleIdentifier
+                    staticElement: self::@function::foo
+                    staticType: int Function()
+                    token: foo @39
+                  staticInvokeType: int Function()
+                  staticType: int
+                fieldName: SimpleIdentifier
+                  staticElement: self::@class::C::@field::x
+                  staticType: null
+                  token: x @35
+        accessors
+          synthetic get x @-1
+            returnType: dynamic
+    functions
+      foo @52
+        returnType: int
+''');
+  }
+
+  test_class_constructor_initializers_field_optionalPositionalParameter() async {
+    var library = await checkLibrary('''
+class A {
+  final int _f;
+  const A([int f = 0]) : _f = f;
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        fields
+          final _f @22
+            type: int
+        constructors
+          const @34
+            parameters
+              optionalPositional f @41
+                type: int
+                constantInitializer
+                  IntegerLiteral
+                    literal: 0 @45
+                    staticType: int
+            constantInitializers
+              ConstructorFieldInitializer
+                equals: = @54
+                expression: SimpleIdentifier
+                  staticElement: self::@class::A::@constructor::•::@parameter::f
+                  staticType: int
+                  token: f @56
+                fieldName: SimpleIdentifier
+                  staticElement: self::@class::A::@field::_f
+                  staticType: null
+                  token: _f @51
+        accessors
+          synthetic get _f @-1
+            returnType: int
+''');
+  }
+
+  test_class_constructor_initializers_field_withParameter() async {
+    var library = await checkLibrary('''
+class C {
+  final x;
+  const C(int p) : x = 1 + p;
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          final x @18
+            type: dynamic
+        constructors
+          const @29
+            parameters
+              requiredPositional p @35
+                type: int
+            constantInitializers
+              ConstructorFieldInitializer
+                equals: = @42
+                expression: BinaryExpression
+                  leftOperand: IntegerLiteral
+                    literal: 1 @44
+                    staticType: int
+                  operator: + @46
+                  rightOperand: SimpleIdentifier
+                    staticElement: p@35
+                    staticType: int
+                    token: p @48
+                  staticElement: dart:core::@class::num::@method::+
+                  staticInvokeType: num Function(num)
+                  staticType: int
+                fieldName: SimpleIdentifier
+                  staticElement: self::@class::C::@field::x
+                  staticType: null
+                  token: x @40
+        accessors
+          synthetic get x @-1
+            returnType: dynamic
+''');
+  }
+
+  test_class_constructor_initializers_genericFunctionType() async {
+    var library = await checkLibrary('''
+class A<T> {
+  const A();
+}
+class B {
+  const B(dynamic x);
+  const B.f()
+   : this(A<Function()>());
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        typeParameters
+          covariant T @8
+            defaultType: dynamic
+        constructors
+          const @21
+      class B @34
+        constructors
+          const @46
+            parameters
+              requiredPositional x @56
+                type: dynamic
+          const f @70
+            periodOffset: 69
+            nameEnd: 71
+            constantInitializers
+              RedirectingConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    InstanceCreationExpression
+                      argumentList: ArgumentList
+                        leftParenthesis: ( @97
+                        rightParenthesis: ) @98
+                      constructorName: ConstructorName
+                        staticElement: ConstructorMember
+                          base: self::@class::A::@constructor::•
+                          substitution: {T: dynamic Function()}
+                        type: NamedType
+                          name: SimpleIdentifier
+                            staticElement: self::@class::A
+                            staticType: null
+                            token: A @84
+                          type: A<dynamic Function()>
+                          typeArguments: TypeArgumentList
+                            arguments
+                              GenericFunctionType
+                                declaredElement: GenericFunctionTypeElement
+                                  parameters
+                                  returnType: dynamic
+                                  type: dynamic Function()
+                                functionKeyword: Function @86
+                                parameters: FormalParameterList
+                                  leftParenthesis: ( @94
+                                  rightParenthesis: ) @95
+                                type: dynamic Function()
+                            leftBracket: < @85
+                            rightBracket: > @96
+                      staticType: A<dynamic Function()>
+                  leftParenthesis: ( @83
+                  rightParenthesis: ) @99
+                staticElement: self::@class::B::@constructor::•
+                thisKeyword: this @79
+            redirectedConstructor: self::@class::B::@constructor::•
+''');
+  }
+
+  test_class_constructor_initializers_superInvocation_argumentContextType() async {
+    var library = await checkLibrary('''
+class A {
+  const A(List<String> values);
+}
+class B extends A {
+  const B() : super(const []);
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          const @18
+            parameters
+              requiredPositional values @33
+                type: List<String>
+      class B @50
+        supertype: A
+        constructors
+          const @72
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    ListLiteral
+                      constKeyword: const @84
+                      leftBracket: [ @90
+                      rightBracket: ] @91
+                      staticType: List<String>
+                  leftParenthesis: ( @83
+                  rightParenthesis: ) @92
+                staticElement: self::@class::A::@constructor::•
+                superKeyword: super @78
+            superConstructor: self::@class::A::@constructor::•
+''');
+  }
+
+  test_class_constructor_initializers_superInvocation_named() async {
+    var library = await checkLibrary('''
+class A {
+  const A.aaa(int p);
+}
+class C extends A {
+  const C() : super.aaa(42);
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          const aaa @20
+            periodOffset: 19
+            nameEnd: 23
+            parameters
+              requiredPositional p @28
+                type: int
+      class C @40
+        supertype: A
+        constructors
+          const @62
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    IntegerLiteral
+                      literal: 42 @78
+                      staticType: int
+                  leftParenthesis: ( @77
+                  rightParenthesis: ) @80
+                constructorName: SimpleIdentifier
+                  staticElement: self::@class::A::@constructor::aaa
+                  staticType: null
+                  token: aaa @74
+                period: . @73
+                staticElement: self::@class::A::@constructor::aaa
+                superKeyword: super @68
+            superConstructor: self::@class::A::@constructor::aaa
+''');
+  }
+
+  test_class_constructor_initializers_superInvocation_named_underscore() async {
+    var library = await checkLibrary('''
+class A {
+  const A._();
+}
+class B extends A {
+  const B() : super._();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          const _ @20
+            periodOffset: 19
+            nameEnd: 21
+      class B @33
+        supertype: A
+        constructors
+          const @55
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @68
+                  rightParenthesis: ) @69
+                constructorName: SimpleIdentifier
+                  staticElement: self::@class::A::@constructor::_
+                  staticType: null
+                  token: _ @67
+                period: . @66
+                staticElement: self::@class::A::@constructor::_
+                superKeyword: super @61
+            superConstructor: self::@class::A::@constructor::_
+''');
+  }
+
+  test_class_constructor_initializers_superInvocation_namedExpression() async {
+    var library = await checkLibrary('''
+class A {
+  const A.aaa(a, {int b});
+}
+class C extends A {
+  const C() : super.aaa(1, b: 2);
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          const aaa @20
+            periodOffset: 19
+            nameEnd: 23
+            parameters
+              requiredPositional a @24
+                type: dynamic
+              optionalNamed b @32
+                type: int
+      class C @45
+        supertype: A
+        constructors
+          const @67
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    IntegerLiteral
+                      literal: 1 @83
+                      staticType: int
+                    NamedExpression
+                      name: Label
+                        label: SimpleIdentifier
+                          staticElement: self::@class::A::@constructor::aaa::@parameter::b
+                          staticType: null
+                          token: b @86
+                      expression: IntegerLiteral
+                        literal: 2 @89
+                        staticType: int
+                  leftParenthesis: ( @82
+                  rightParenthesis: ) @90
+                constructorName: SimpleIdentifier
+                  staticElement: self::@class::A::@constructor::aaa
+                  staticType: null
+                  token: aaa @79
+                period: . @78
+                staticElement: self::@class::A::@constructor::aaa
+                superKeyword: super @73
+            superConstructor: self::@class::A::@constructor::aaa
+''');
+  }
+
+  test_class_constructor_initializers_superInvocation_unnamed() async {
+    var library = await checkLibrary('''
+class A {
+  const A(int p);
+}
+class C extends A {
+  const C.ccc() : super(42);
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          const @18
+            parameters
+              requiredPositional p @24
+                type: int
+      class C @36
+        supertype: A
+        constructors
+          const ccc @60
+            periodOffset: 59
+            nameEnd: 63
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    IntegerLiteral
+                      literal: 42 @74
+                      staticType: int
+                  leftParenthesis: ( @73
+                  rightParenthesis: ) @76
+                staticElement: self::@class::A::@constructor::•
+                superKeyword: super @68
+            superConstructor: self::@class::A::@constructor::•
+''');
+  }
+
+  test_class_constructor_initializers_thisInvocation_argumentContextType() async {
+    var library = await checkLibrary('''
+class A {
+  const A(List<String> values);
+  const A.empty() : this(const []);
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          const @18
+            parameters
+              requiredPositional values @33
+                type: List<String>
+          const empty @52
+            periodOffset: 51
+            nameEnd: 57
+            constantInitializers
+              RedirectingConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    ListLiteral
+                      constKeyword: const @67
+                      leftBracket: [ @73
+                      rightBracket: ] @74
+                      staticType: List<String>
+                  leftParenthesis: ( @66
+                  rightParenthesis: ) @75
+                staticElement: self::@class::A::@constructor::•
+                thisKeyword: this @62
+            redirectedConstructor: self::@class::A::@constructor::•
+''');
+  }
+
+  test_class_constructor_initializers_thisInvocation_named() async {
+    var library = await checkLibrary('''
+class C {
+  const C() : this.named(1, 'bbb');
+  const C.named(int a, String b);
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          const @18
+            constantInitializers
+              RedirectingConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    IntegerLiteral
+                      literal: 1 @35
+                      staticType: int
+                    SimpleStringLiteral
+                      literal: 'bbb' @38
+                  leftParenthesis: ( @34
+                  rightParenthesis: ) @43
+                constructorName: SimpleIdentifier
+                  staticElement: self::@class::C::@constructor::named
+                  staticType: null
+                  token: named @29
+                period: . @28
+                staticElement: self::@class::C::@constructor::named
+                thisKeyword: this @24
+            redirectedConstructor: self::@class::C::@constructor::named
+          const named @56
+            periodOffset: 55
+            nameEnd: 61
+            parameters
+              requiredPositional a @66
+                type: int
+              requiredPositional b @76
+                type: String
+''');
+  }
+
+  test_class_constructor_initializers_thisInvocation_namedExpression() async {
+    var library = await checkLibrary('''
+class C {
+  const C() : this.named(1, b: 2);
+  const C.named(a, {int b});
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          const @18
+            constantInitializers
+              RedirectingConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    IntegerLiteral
+                      literal: 1 @35
+                      staticType: int
+                    NamedExpression
+                      name: Label
+                        label: SimpleIdentifier
+                          staticElement: self::@class::C::@constructor::named::@parameter::b
+                          staticType: null
+                          token: b @38
+                      expression: IntegerLiteral
+                        literal: 2 @41
+                        staticType: int
+                  leftParenthesis: ( @34
+                  rightParenthesis: ) @42
+                constructorName: SimpleIdentifier
+                  staticElement: self::@class::C::@constructor::named
+                  staticType: null
+                  token: named @29
+                period: . @28
+                staticElement: self::@class::C::@constructor::named
+                thisKeyword: this @24
+            redirectedConstructor: self::@class::C::@constructor::named
+          const named @55
+            periodOffset: 54
+            nameEnd: 60
+            parameters
+              requiredPositional a @61
+                type: dynamic
+              optionalNamed b @69
+                type: int
+''');
+  }
+
+  test_class_constructor_initializers_thisInvocation_unnamed() async {
+    var library = await checkLibrary('''
+class C {
+  const C.named() : this(1, 'bbb');
+  const C(int a, String b);
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          const named @20
+            periodOffset: 19
+            nameEnd: 25
+            constantInitializers
+              RedirectingConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    IntegerLiteral
+                      literal: 1 @35
+                      staticType: int
+                    SimpleStringLiteral
+                      literal: 'bbb' @38
+                  leftParenthesis: ( @34
+                  rightParenthesis: ) @43
+                staticElement: self::@class::C::@constructor::•
+                thisKeyword: this @30
+            redirectedConstructor: self::@class::C::@constructor::•
+          const @54
+            parameters
+              requiredPositional a @60
+                type: int
+              requiredPositional b @70
+                type: String
+''');
+  }
+
+  @FailingTest(issue: 'https://github.com/dart-lang/sdk/issues/47951')
+  test_class_constructor_parameters_super_explicitType_function() async {
+    var library = await checkLibrary('''
+class A {
+  A(Object? a);
+}
+
+class B extends A {
+  B(int super.a<T extends num>(T d)?);
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          @12
+            parameters
+              requiredPositional a @22
+                type: Object?
+      class B @35
+        supertype: A
+        constructors
+          @51
+            parameters
+              requiredPositional final super.a @63
+                type: int Function<T extends num>(T)?
+                typeParameters
+                  covariant T @65
+                    bound: num
+                parameters
+                  requiredPositional d @82
+                    type: T
+                superConstructorParameter: a@22
+            superConstructor: self::@class::A::@constructor::•
+''');
+  }
+
+  @FailingTest(issue: 'https://github.com/dart-lang/sdk/issues/47951')
+  test_class_constructor_parameters_super_explicitType_interface() async {
+    var library = await checkLibrary('''
+class A {
+  A(num a);
+}
+
+class B extends A {
+  B(int super.a);
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          @12
+            parameters
+              requiredPositional a @18
+                type: num
+      class B @31
+        supertype: A
+        constructors
+          @47
+            parameters
+              requiredPositional final super.a @49
+                type: int
+                superConstructorParameter: a@18
+            superConstructor: self::@class::A::@constructor::•
+''');
+  }
+
+  test_class_constructor_parameters_super_invalid_topFunction() async {
+    var library = await checkLibrary('''
+void f(super.a) {}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    functions
+      f @5
+        parameters
+          requiredPositional final super.a @13
+            type: dynamic
+            superConstructorParameter: <null>
+        returnType: void
+''');
+  }
+
+  test_class_constructor_parameters_super_optionalNamed() async {
+    var library = await checkLibrary('''
+class A {
+  A({required int a, required double b});
+}
+
+class B extends A {
+  B({String o1, super.a, String o2, super.b}) : super();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          @12
+            parameters
+              requiredNamed a @28
+                type: int
+              requiredNamed b @47
+                type: double
+      class B @61
+        supertype: A
+        constructors
+          @77
+            parameters
+              optionalNamed o1 @87
+                type: String
+              optionalNamed final super.a @97
+                type: int
+                superConstructorParameter: self::@class::A::@constructor::•::@parameter::a
+              optionalNamed o2 @107
+                type: String
+              optionalNamed final super.b @117
+                type: double
+                superConstructorParameter: self::@class::A::@constructor::•::@parameter::b
+            superConstructor: self::@class::A::@constructor::•
+''');
+  }
+
+  test_class_constructor_parameters_super_optionalNamed_unresolved() async {
+    var library = await checkLibrary('''
+class A {
+  A({required int a});
+}
+
+class B extends A {
+  B({super.b});
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          @12
+            parameters
+              requiredNamed a @28
+                type: int
+      class B @42
+        supertype: A
+        constructors
+          @58
+            parameters
+              optionalNamed final super.b @67
+                type: dynamic
+                superConstructorParameter: <null>
+            superConstructor: self::@class::A::@constructor::•
+''');
+  }
+
+  test_class_constructor_parameters_super_optionalPositional() async {
+    var library = await checkLibrary('''
+class A {
+  A(int a, double b);
+}
+
+class B extends A {
+  B([String o1, super.a, String o2, super.b]) : super();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          @12
+            parameters
+              requiredPositional a @18
+                type: int
+              requiredPositional b @28
+                type: double
+      class B @41
+        supertype: A
+        constructors
+          @57
+            parameters
+              optionalPositional o1 @67
+                type: String
+              optionalPositional final super.a @77
+                type: int
+                superConstructorParameter: a@18
+              optionalPositional o2 @87
+                type: String
+              optionalPositional final super.b @97
+                type: double
+                superConstructorParameter: b@28
+            superConstructor: self::@class::A::@constructor::•
+''');
+  }
+
+  test_class_constructor_parameters_super_requiredNamed() async {
+    var library = await checkLibrary('''
+class A {
+  A({required int a, required double b});
+}
+
+class B extends A {
+  B({
+    required String o1,
+    required super.a,
+    required String o2,
+    required super.b,
+  }) : super();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          @12
+            parameters
+              requiredNamed a @28
+                type: int
+              requiredNamed b @47
+                type: double
+      class B @61
+        supertype: A
+        constructors
+          @77
+            parameters
+              requiredNamed o1 @101
+                type: String
+              requiredNamed final super.a @124
+                type: int
+                superConstructorParameter: self::@class::A::@constructor::•::@parameter::a
+              requiredNamed o2 @147
+                type: String
+              requiredNamed final super.b @170
+                type: double
+                superConstructorParameter: self::@class::A::@constructor::•::@parameter::b
+            superConstructor: self::@class::A::@constructor::•
+''');
+  }
+
+  test_class_constructor_parameters_super_requiredPositional() async {
+    var library = await checkLibrary('''
+class A {
+  A(int a, double b);
+}
+
+class B extends A {
+  B(String o1, super.a, String o2, super.b) : super();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          @12
+            parameters
+              requiredPositional a @18
+                type: int
+              requiredPositional b @28
+                type: double
+      class B @41
+        supertype: A
+        constructors
+          @57
+            parameters
+              requiredPositional o1 @66
+                type: String
+              requiredPositional final super.a @76
+                type: int
+                superConstructorParameter: a@18
+              requiredPositional o2 @86
+                type: String
+              requiredPositional final super.b @96
+                type: double
+                superConstructorParameter: b@28
+            superConstructor: self::@class::A::@constructor::•
+''');
+  }
+
+  test_class_constructor_parameters_super_requiredPositional_unresolved() async {
+    var library = await checkLibrary('''
+class A {}
+
+class B extends A {
+  B(super.a);
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          synthetic @-1
+      class B @18
+        supertype: A
+        constructors
+          @34
+            parameters
+              requiredPositional final super.a @42
+                type: dynamic
+                superConstructorParameter: <null>
+            superConstructor: self::@class::A::@constructor::•
+''');
+  }
+
   test_class_constructor_params() async {
     var library = await checkLibrary('class C { C(x, int y); }');
     checkElementText(library, r'''
@@ -1509,6 +1787,976 @@
 ''');
   }
 
+  test_class_constructor_redirected_factory_named() async {
+    var library = await checkLibrary('''
+class C {
+  factory C() = D.named;
+  C._();
+}
+class D extends C {
+  D.named() : super._();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          factory @20
+            redirectedConstructor: self::@class::D::@constructor::named
+          _ @39
+            periodOffset: 38
+            nameEnd: 40
+      class D @52
+        supertype: C
+        constructors
+          named @70
+            periodOffset: 69
+            nameEnd: 75
+            superConstructor: self::@class::C::@constructor::_
+''');
+  }
+
+  test_class_constructor_redirected_factory_named_generic() async {
+    var library = await checkLibrary('''
+class C<T, U> {
+  factory C() = D<U, T>.named;
+  C._();
+}
+class D<T, U> extends C<U, T> {
+  D.named() : super._();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        typeParameters
+          covariant T @8
+            defaultType: dynamic
+          covariant U @11
+            defaultType: dynamic
+        constructors
+          factory @26
+            redirectedConstructor: ConstructorMember
+              base: self::@class::D::@constructor::named
+              substitution: {T: U, U: T}
+          _ @51
+            periodOffset: 50
+            nameEnd: 52
+      class D @64
+        typeParameters
+          covariant T @66
+            defaultType: dynamic
+          covariant U @69
+            defaultType: dynamic
+        supertype: C<U, T>
+        constructors
+          named @94
+            periodOffset: 93
+            nameEnd: 99
+            superConstructor: ConstructorMember
+              base: self::@class::C::@constructor::_
+              substitution: {T: U, U: T}
+''');
+  }
+
+  test_class_constructor_redirected_factory_named_generic_viaTypeAlias() async {
+    var library = await checkLibrary('''
+typedef A<T, U> = C<T, U>;
+class B<T, U> {
+  factory B() = A<U, T>.named;
+  B._();
+}
+class C<T, U> extends A<U, T> {
+  C.named() : super._();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class B @33
+        typeParameters
+          covariant T @35
+            defaultType: dynamic
+          covariant U @38
+            defaultType: dynamic
+        constructors
+          factory @53
+            redirectedConstructor: ConstructorMember
+              base: self::@class::C::@constructor::named
+              substitution: {T: U, U: T}
+          _ @78
+            periodOffset: 77
+            nameEnd: 79
+      class C @91
+        typeParameters
+          covariant T @93
+            defaultType: dynamic
+          covariant U @96
+            defaultType: dynamic
+        supertype: C<U, T>
+          aliasElement: self::@typeAlias::A
+          aliasArguments
+            U
+            T
+        constructors
+          named @121
+            periodOffset: 120
+            nameEnd: 126
+    typeAliases
+      A @8
+        typeParameters
+          covariant T @10
+            defaultType: dynamic
+          covariant U @13
+            defaultType: dynamic
+        aliasedType: C<T, U>
+''');
+  }
+
+  test_class_constructor_redirected_factory_named_imported() async {
+    addLibrarySource('/foo.dart', '''
+import 'test.dart';
+class D extends C {
+  D.named() : super._();
+}
+''');
+    var library = await checkLibrary('''
+import 'foo.dart';
+class C {
+  factory C() = D.named;
+  C._();
+}
+''');
+    checkElementText(library, r'''
+library
+  imports
+    foo.dart
+  definingUnit
+    classes
+      class C @25
+        constructors
+          factory @39
+            redirectedConstructor: foo.dart::@class::D::@constructor::named
+          _ @58
+            periodOffset: 57
+            nameEnd: 59
+''');
+  }
+
+  test_class_constructor_redirected_factory_named_imported_generic() async {
+    addLibrarySource('/foo.dart', '''
+import 'test.dart';
+class D<T, U> extends C<U, T> {
+  D.named() : super._();
+}
+''');
+    var library = await checkLibrary('''
+import 'foo.dart';
+class C<T, U> {
+  factory C() = D<U, T>.named;
+  C._();
+}
+''');
+    checkElementText(library, r'''
+library
+  imports
+    foo.dart
+  definingUnit
+    classes
+      class C @25
+        typeParameters
+          covariant T @27
+            defaultType: dynamic
+          covariant U @30
+            defaultType: dynamic
+        constructors
+          factory @45
+            redirectedConstructor: ConstructorMember
+              base: foo.dart::@class::D::@constructor::named
+              substitution: {T: U, U: T}
+          _ @70
+            periodOffset: 69
+            nameEnd: 71
+''');
+  }
+
+  test_class_constructor_redirected_factory_named_prefixed() async {
+    addLibrarySource('/foo.dart', '''
+import 'test.dart';
+class D extends C {
+  D.named() : super._();
+}
+''');
+    var library = await checkLibrary('''
+import 'foo.dart' as foo;
+class C {
+  factory C() = foo.D.named;
+  C._();
+}
+''');
+    checkElementText(library, r'''
+library
+  imports
+    foo.dart as foo @21
+  definingUnit
+    classes
+      class C @32
+        constructors
+          factory @46
+            redirectedConstructor: foo.dart::@class::D::@constructor::named
+          _ @69
+            periodOffset: 68
+            nameEnd: 70
+''');
+  }
+
+  test_class_constructor_redirected_factory_named_prefixed_generic() async {
+    addLibrarySource('/foo.dart', '''
+import 'test.dart';
+class D<T, U> extends C<U, T> {
+  D.named() : super._();
+}
+''');
+    var library = await checkLibrary('''
+import 'foo.dart' as foo;
+class C<T, U> {
+  factory C() = foo.D<U, T>.named;
+  C._();
+}
+''');
+    checkElementText(library, r'''
+library
+  imports
+    foo.dart as foo @21
+  definingUnit
+    classes
+      class C @32
+        typeParameters
+          covariant T @34
+            defaultType: dynamic
+          covariant U @37
+            defaultType: dynamic
+        constructors
+          factory @52
+            redirectedConstructor: ConstructorMember
+              base: foo.dart::@class::D::@constructor::named
+              substitution: {T: U, U: T}
+          _ @81
+            periodOffset: 80
+            nameEnd: 82
+''');
+  }
+
+  test_class_constructor_redirected_factory_named_unresolved_class() async {
+    var library = await checkLibrary('''
+class C<E> {
+  factory C() = D.named<E>;
+}
+''', allowErrors: true);
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        typeParameters
+          covariant E @8
+            defaultType: dynamic
+        constructors
+          factory @23
+''');
+  }
+
+  test_class_constructor_redirected_factory_named_unresolved_constructor() async {
+    var library = await checkLibrary('''
+class D {}
+class C<E> {
+  factory C() = D.named<E>;
+}
+''', allowErrors: true);
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class D @6
+        constructors
+          synthetic @-1
+      class C @17
+        typeParameters
+          covariant E @19
+            defaultType: dynamic
+        constructors
+          factory @34
+''');
+  }
+
+  test_class_constructor_redirected_factory_unnamed() async {
+    var library = await checkLibrary('''
+class C {
+  factory C() = D;
+  C._();
+}
+class D extends C {
+  D() : super._();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          factory @20
+            redirectedConstructor: self::@class::D::@constructor::•
+          _ @33
+            periodOffset: 32
+            nameEnd: 34
+      class D @46
+        supertype: C
+        constructors
+          @62
+            superConstructor: self::@class::C::@constructor::_
+''');
+  }
+
+  test_class_constructor_redirected_factory_unnamed_generic() async {
+    var library = await checkLibrary('''
+class C<T, U> {
+  factory C() = D<U, T>;
+  C._();
+}
+class D<T, U> extends C<U, T> {
+  D() : super._();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        typeParameters
+          covariant T @8
+            defaultType: dynamic
+          covariant U @11
+            defaultType: dynamic
+        constructors
+          factory @26
+            redirectedConstructor: ConstructorMember
+              base: self::@class::D::@constructor::•
+              substitution: {T: U, U: T}
+          _ @45
+            periodOffset: 44
+            nameEnd: 46
+      class D @58
+        typeParameters
+          covariant T @60
+            defaultType: dynamic
+          covariant U @63
+            defaultType: dynamic
+        supertype: C<U, T>
+        constructors
+          @86
+            superConstructor: ConstructorMember
+              base: self::@class::C::@constructor::_
+              substitution: {T: U, U: T}
+''');
+  }
+
+  test_class_constructor_redirected_factory_unnamed_generic_viaTypeAlias() async {
+    var library = await checkLibrary('''
+typedef A<T, U> = C<T, U>;
+class B<T, U> {
+  factory B() = A<U, T>;
+  B_();
+}
+class C<T, U> extends B<U, T> {
+  C() : super._();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class B @33
+        typeParameters
+          covariant T @35
+            defaultType: dynamic
+          covariant U @38
+            defaultType: dynamic
+        constructors
+          factory @53
+            redirectedConstructor: ConstructorMember
+              base: self::@class::C::@constructor::•
+              substitution: {T: U, U: T}
+        methods
+          abstract B_ @70
+            returnType: dynamic
+      class C @84
+        typeParameters
+          covariant T @86
+            defaultType: dynamic
+          covariant U @89
+            defaultType: dynamic
+        supertype: B<U, T>
+        constructors
+          @112
+    typeAliases
+      A @8
+        typeParameters
+          covariant T @10
+            defaultType: dynamic
+          covariant U @13
+            defaultType: dynamic
+        aliasedType: C<T, U>
+''');
+  }
+
+  test_class_constructor_redirected_factory_unnamed_imported() async {
+    addLibrarySource('/foo.dart', '''
+import 'test.dart';
+class D extends C {
+  D() : super._();
+}
+''');
+    var library = await checkLibrary('''
+import 'foo.dart';
+class C {
+  factory C() = D;
+  C._();
+}
+''');
+    checkElementText(library, r'''
+library
+  imports
+    foo.dart
+  definingUnit
+    classes
+      class C @25
+        constructors
+          factory @39
+            redirectedConstructor: foo.dart::@class::D::@constructor::•
+          _ @52
+            periodOffset: 51
+            nameEnd: 53
+''');
+  }
+
+  test_class_constructor_redirected_factory_unnamed_imported_generic() async {
+    addLibrarySource('/foo.dart', '''
+import 'test.dart';
+class D<T, U> extends C<U, T> {
+  D() : super._();
+}
+''');
+    var library = await checkLibrary('''
+import 'foo.dart';
+class C<T, U> {
+  factory C() = D<U, T>;
+  C._();
+}
+''');
+    checkElementText(library, r'''
+library
+  imports
+    foo.dart
+  definingUnit
+    classes
+      class C @25
+        typeParameters
+          covariant T @27
+            defaultType: dynamic
+          covariant U @30
+            defaultType: dynamic
+        constructors
+          factory @45
+            redirectedConstructor: ConstructorMember
+              base: foo.dart::@class::D::@constructor::•
+              substitution: {T: U, U: T}
+          _ @64
+            periodOffset: 63
+            nameEnd: 65
+''');
+  }
+
+  test_class_constructor_redirected_factory_unnamed_imported_viaTypeAlias() async {
+    addLibrarySource('/foo.dart', '''
+import 'test.dart';
+typedef A = B;
+class B extends C {
+  B() : super._();
+}
+''');
+    var library = await checkLibrary('''
+import 'foo.dart';
+class C {
+  factory C() = A;
+  C._();
+}
+''');
+    checkElementText(library, r'''
+library
+  imports
+    foo.dart
+  definingUnit
+    classes
+      class C @25
+        constructors
+          factory @39
+            redirectedConstructor: foo.dart::@class::B::@constructor::•
+          _ @52
+            periodOffset: 51
+            nameEnd: 53
+''');
+  }
+
+  test_class_constructor_redirected_factory_unnamed_prefixed() async {
+    addLibrarySource('/foo.dart', '''
+import 'test.dart';
+class D extends C {
+  D() : super._();
+}
+''');
+    var library = await checkLibrary('''
+import 'foo.dart' as foo;
+class C {
+  factory C() = foo.D;
+  C._();
+}
+''');
+    checkElementText(library, r'''
+library
+  imports
+    foo.dart as foo @21
+  definingUnit
+    classes
+      class C @32
+        constructors
+          factory @46
+            redirectedConstructor: foo.dart::@class::D::@constructor::•
+          _ @63
+            periodOffset: 62
+            nameEnd: 64
+''');
+  }
+
+  test_class_constructor_redirected_factory_unnamed_prefixed_generic() async {
+    addLibrarySource('/foo.dart', '''
+import 'test.dart';
+class D<T, U> extends C<U, T> {
+  D() : super._();
+}
+''');
+    var library = await checkLibrary('''
+import 'foo.dart' as foo;
+class C<T, U> {
+  factory C() = foo.D<U, T>;
+  C._();
+}
+''');
+    checkElementText(library, r'''
+library
+  imports
+    foo.dart as foo @21
+  definingUnit
+    classes
+      class C @32
+        typeParameters
+          covariant T @34
+            defaultType: dynamic
+          covariant U @37
+            defaultType: dynamic
+        constructors
+          factory @52
+            redirectedConstructor: ConstructorMember
+              base: foo.dart::@class::D::@constructor::•
+              substitution: {T: U, U: T}
+          _ @75
+            periodOffset: 74
+            nameEnd: 76
+''');
+  }
+
+  test_class_constructor_redirected_factory_unnamed_prefixed_viaTypeAlias() async {
+    addLibrarySource('/foo.dart', '''
+import 'test.dart';
+typedef A = B;
+class B extends C {
+  B() : super._();
+}
+''');
+    var library = await checkLibrary('''
+import 'foo.dart' as foo;
+class C {
+  factory C() = foo.A;
+  C._();
+}
+''');
+    checkElementText(library, r'''
+library
+  imports
+    foo.dart as foo @21
+  definingUnit
+    classes
+      class C @32
+        constructors
+          factory @46
+            redirectedConstructor: foo.dart::@class::B::@constructor::•
+          _ @63
+            periodOffset: 62
+            nameEnd: 64
+''');
+  }
+
+  test_class_constructor_redirected_factory_unnamed_unresolved() async {
+    var library = await checkLibrary('''
+class C<E> {
+  factory C() = D<E>;
+}
+''', allowErrors: true);
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        typeParameters
+          covariant E @8
+            defaultType: dynamic
+        constructors
+          factory @23
+''');
+  }
+
+  test_class_constructor_redirected_factory_unnamed_viaTypeAlias() async {
+    var library = await checkLibrary('''
+typedef A = C;
+class B {
+  factory B() = A;
+  B._();
+}
+class C extends B {
+  C() : super._();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class B @21
+        constructors
+          factory @35
+            redirectedConstructor: self::@class::C::@constructor::•
+          _ @48
+            periodOffset: 47
+            nameEnd: 49
+      class C @61
+        supertype: B
+        constructors
+          @77
+            superConstructor: self::@class::B::@constructor::_
+    typeAliases
+      A @8
+        aliasedType: C
+''');
+  }
+
+  test_class_constructor_redirected_thisInvocation_named() async {
+    var library = await checkLibrary('''
+class C {
+  const C.named();
+  const C() : this.named();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          const named @20
+            periodOffset: 19
+            nameEnd: 25
+          const @37
+            constantInitializers
+              RedirectingConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @53
+                  rightParenthesis: ) @54
+                constructorName: SimpleIdentifier
+                  staticElement: self::@class::C::@constructor::named
+                  staticType: null
+                  token: named @48
+                period: . @47
+                staticElement: self::@class::C::@constructor::named
+                thisKeyword: this @43
+            redirectedConstructor: self::@class::C::@constructor::named
+''');
+  }
+
+  test_class_constructor_redirected_thisInvocation_named_generic() async {
+    var library = await checkLibrary('''
+class C<T> {
+  const C.named();
+  const C() : this.named();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        typeParameters
+          covariant T @8
+            defaultType: dynamic
+        constructors
+          const named @23
+            periodOffset: 22
+            nameEnd: 28
+          const @40
+            constantInitializers
+              RedirectingConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @56
+                  rightParenthesis: ) @57
+                constructorName: SimpleIdentifier
+                  staticElement: self::@class::C::@constructor::named
+                  staticType: null
+                  token: named @51
+                period: . @50
+                staticElement: self::@class::C::@constructor::named
+                thisKeyword: this @46
+            redirectedConstructor: self::@class::C::@constructor::named
+''');
+  }
+
+  test_class_constructor_redirected_thisInvocation_named_notConst() async {
+    var library = await checkLibrary('''
+class C {
+  C.named();
+  C() : this.named();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          named @14
+            periodOffset: 13
+            nameEnd: 19
+          @25
+            redirectedConstructor: self::@class::C::@constructor::named
+''');
+  }
+
+  test_class_constructor_redirected_thisInvocation_unnamed() async {
+    var library = await checkLibrary('''
+class C {
+  const C();
+  const C.named() : this();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          const @18
+          const named @33
+            periodOffset: 32
+            nameEnd: 38
+            constantInitializers
+              RedirectingConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @47
+                  rightParenthesis: ) @48
+                staticElement: self::@class::C::@constructor::•
+                thisKeyword: this @43
+            redirectedConstructor: self::@class::C::@constructor::•
+''');
+  }
+
+  test_class_constructor_redirected_thisInvocation_unnamed_generic() async {
+    var library = await checkLibrary('''
+class C<T> {
+  const C();
+  const C.named() : this();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        typeParameters
+          covariant T @8
+            defaultType: dynamic
+        constructors
+          const @21
+          const named @36
+            periodOffset: 35
+            nameEnd: 41
+            constantInitializers
+              RedirectingConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @50
+                  rightParenthesis: ) @51
+                staticElement: self::@class::C::@constructor::•
+                thisKeyword: this @46
+            redirectedConstructor: self::@class::C::@constructor::•
+''');
+  }
+
+  test_class_constructor_redirected_thisInvocation_unnamed_notConst() async {
+    var library = await checkLibrary('''
+class C {
+  C();
+  C.named() : this();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          @12
+          named @21
+            periodOffset: 20
+            nameEnd: 26
+            redirectedConstructor: self::@class::C::@constructor::•
+''');
+  }
+
+  test_class_constructor_superConstructor_generic_named() async {
+    var library = await checkLibrary('''
+class A<T> {
+  A.named(T a);
+}
+class B extends A<int> {
+  B() : super.named(0);
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        typeParameters
+          covariant T @8
+            defaultType: dynamic
+        constructors
+          named @17
+            periodOffset: 16
+            nameEnd: 22
+            parameters
+              requiredPositional a @25
+                type: T
+      class B @37
+        supertype: A<int>
+        constructors
+          @58
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::named
+              substitution: {T: int}
+''');
+  }
+
+  test_class_constructor_superConstructor_notGeneric_named() async {
+    var library = await checkLibrary('''
+class A {
+  A.named();
+}
+class B extends A {
+  B() : super.named();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          named @14
+            periodOffset: 13
+            nameEnd: 19
+      class B @31
+        supertype: A
+        constructors
+          @47
+            superConstructor: self::@class::A::@constructor::named
+''');
+  }
+
+  test_class_constructor_superConstructor_notGeneric_unnamed_explicit() async {
+    var library = await checkLibrary('''
+class A {}
+class B extends A {
+  B() : super();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          synthetic @-1
+      class B @17
+        supertype: A
+        constructors
+          @33
+            superConstructor: self::@class::A::@constructor::•
+''');
+  }
+
+  test_class_constructor_superConstructor_notGeneric_unnamed_implicit() async {
+    var library = await checkLibrary('''
+class A {}
+class B extends A {
+  B();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          synthetic @-1
+      class B @17
+        supertype: A
+        constructors
+          @33
+            superConstructor: self::@class::A::@constructor::•
+''');
+  }
+
+  test_class_constructor_superConstructor_notGeneric_unnamed_implicit2() async {
+    var library = await checkLibrary('''
+class A {}
+class B extends A {}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        constructors
+          synthetic @-1
+      class B @17
+        supertype: A
+        constructors
+          synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
+''');
+  }
+
   test_class_constructor_unnamed_implicit() async {
     var library = await checkLibrary('class C {}');
     checkElementText(
@@ -1525,6 +2773,120 @@
         withDisplayName: true);
   }
 
+  test_class_constructor_withCycles_const() async {
+    var library = await checkLibrary('''
+class C {
+  final x;
+  const C() : x = const D();
+}
+class D {
+  final x;
+  const D() : x = const C();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          final x @18
+            type: dynamic
+        constructors
+          const @29
+            constantInitializers
+              ConstructorFieldInitializer
+                equals: = @37
+                expression: InstanceCreationExpression
+                  argumentList: ArgumentList
+                    leftParenthesis: ( @46
+                    rightParenthesis: ) @47
+                  constructorName: ConstructorName
+                    staticElement: self::@class::D::@constructor::•
+                    type: NamedType
+                      name: SimpleIdentifier
+                        staticElement: self::@class::D
+                        staticType: null
+                        token: D @45
+                      type: D
+                  keyword: const @39
+                  staticType: D
+                fieldName: SimpleIdentifier
+                  staticElement: self::@class::C::@field::x
+                  staticType: null
+                  token: x @35
+        accessors
+          synthetic get x @-1
+            returnType: dynamic
+      class D @58
+        fields
+          final x @70
+            type: dynamic
+        constructors
+          const @81
+            constantInitializers
+              ConstructorFieldInitializer
+                equals: = @89
+                expression: InstanceCreationExpression
+                  argumentList: ArgumentList
+                    leftParenthesis: ( @98
+                    rightParenthesis: ) @99
+                  constructorName: ConstructorName
+                    staticElement: self::@class::C::@constructor::•
+                    type: NamedType
+                      name: SimpleIdentifier
+                        staticElement: self::@class::C
+                        staticType: null
+                        token: C @97
+                      type: C
+                  keyword: const @91
+                  staticType: C
+                fieldName: SimpleIdentifier
+                  staticElement: self::@class::D::@field::x
+                  staticType: null
+                  token: x @87
+        accessors
+          synthetic get x @-1
+            returnType: dynamic
+''');
+  }
+
+  test_class_constructor_withCycles_nonConst() async {
+    var library = await checkLibrary('''
+class C {
+  final x;
+  C() : x = new D();
+}
+class D {
+  final x;
+  D() : x = new C();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          final x @18
+            type: dynamic
+        constructors
+          @23
+        accessors
+          synthetic get x @-1
+            returnType: dynamic
+      class D @50
+        fields
+          final x @62
+            type: dynamic
+        constructors
+          @67
+        accessors
+          synthetic get x @-1
+            returnType: dynamic
+''');
+  }
+
   test_class_constructors_named() async {
     var library = await checkLibrary('''
 class C {
@@ -1873,6 +3235,33 @@
 ''');
   }
 
+  test_class_field_abstract() async {
+    var library = await checkLibrary('''
+abstract class C {
+  abstract int i;
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      abstract class C @15
+        fields
+          abstract i @34
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          synthetic abstract get i @-1
+            returnType: int
+          synthetic abstract set i @-1
+            parameters
+              requiredPositional _i @-1
+                type: int
+            returnType: void
+''');
+  }
+
   test_class_field_const() async {
     var library = await checkLibrary('class C { static const int i = 0; }');
     checkElementText(library, r'''
@@ -1918,6 +3307,224 @@
 ''');
   }
 
+  test_class_field_covariant() async {
+    var library = await checkLibrary('''
+class C {
+  covariant int x;
+}''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          covariant x @26
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          synthetic get x @-1
+            returnType: int
+          synthetic set x @-1
+            parameters
+              requiredPositional covariant _x @-1
+                type: int
+            returnType: void
+''');
+  }
+
+  test_class_field_documented() async {
+    var library = await checkLibrary('''
+class C {
+  /**
+   * Docs
+   */
+  var x;
+}''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          x @38
+            documentationComment: /**\n   * Docs\n   */
+            type: dynamic
+        constructors
+          synthetic @-1
+        accessors
+          synthetic get x @-1
+            returnType: dynamic
+          synthetic set x @-1
+            parameters
+              requiredPositional _x @-1
+                type: dynamic
+            returnType: void
+''');
+  }
+
+  test_class_field_external() async {
+    var library = await checkLibrary('''
+abstract class C {
+  external int i;
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      abstract class C @15
+        fields
+          external i @34
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          synthetic get i @-1
+            returnType: int
+          synthetic set i @-1
+            parameters
+              requiredPositional _i @-1
+                type: int
+            returnType: void
+''');
+  }
+
+  test_class_field_final_hasInitializer_hasConstConstructor() async {
+    var library = await checkLibrary('''
+class C {
+  final x = 42;
+  const C();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          final x @18
+            type: int
+            constantInitializer
+              IntegerLiteral
+                literal: 42 @22
+                staticType: int
+        constructors
+          const @34
+        accessors
+          synthetic get x @-1
+            returnType: int
+''');
+  }
+
+  test_class_field_final_hasInitializer_hasConstConstructor_genericFunctionType() async {
+    var library = await checkLibrary('''
+class A<T> {
+  const A();
+}
+class B {
+  final f = const A<int Function(double a)>();
+  const B();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        typeParameters
+          covariant T @8
+            defaultType: dynamic
+        constructors
+          const @21
+      class B @34
+        fields
+          final f @46
+            type: A<int Function(double)>
+            constantInitializer
+              InstanceCreationExpression
+                argumentList: ArgumentList
+                  leftParenthesis: ( @81
+                  rightParenthesis: ) @82
+                constructorName: ConstructorName
+                  staticElement: ConstructorMember
+                    base: self::@class::A::@constructor::•
+                    substitution: {T: int Function(double)}
+                  type: NamedType
+                    name: SimpleIdentifier
+                      staticElement: self::@class::A
+                      staticType: null
+                      token: A @56
+                    type: A<int Function(double)>
+                    typeArguments: TypeArgumentList
+                      arguments
+                        GenericFunctionType
+                          declaredElement: GenericFunctionTypeElement
+                            parameters
+                              a
+                                kind: required positional
+                                type: double
+                            returnType: int
+                            type: int Function(double)
+                          functionKeyword: Function @62
+                          parameters: FormalParameterList
+                            leftParenthesis: ( @70
+                            parameters
+                              SimpleFormalParameter
+                                declaredElement: a@78
+                                declaredElementType: double
+                                identifier: SimpleIdentifier
+                                  staticElement: a@78
+                                  staticType: null
+                                  token: a @78
+                                type: NamedType
+                                  name: SimpleIdentifier
+                                    staticElement: dart:core::@class::double
+                                    staticType: null
+                                    token: double @71
+                                  type: double
+                            rightParenthesis: ) @79
+                          returnType: NamedType
+                            name: SimpleIdentifier
+                              staticElement: dart:core::@class::int
+                              staticType: null
+                              token: int @58
+                            type: int
+                          type: int Function(double)
+                      leftBracket: < @57
+                      rightBracket: > @80
+                keyword: const @50
+                staticType: A<int Function(double)>
+        constructors
+          const @93
+        accessors
+          synthetic get f @-1
+            returnType: A<int Function(double)>
+''');
+  }
+
+  test_class_field_final_hasInitializer_noConstConstructor() async {
+    var library = await checkLibrary('''
+class C {
+  final x = 42;
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          final x @18
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          synthetic get x @-1
+            returnType: int
+''');
+  }
+
   test_class_field_final_withSetter() async {
     var library = await checkLibrary(r'''
 class A {
@@ -1950,6 +3557,44 @@
 ''');
   }
 
+  test_class_field_formal_param_inferred_type_implicit() async {
+    var library = await checkLibrary('class C extends D { var v; C(this.v); }'
+        ' abstract class D { int get v; }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        supertype: D
+        fields
+          v @24
+            type: int
+        constructors
+          @27
+            parameters
+              requiredPositional final this.v @34
+                type: int
+            superConstructor: self::@class::D::@constructor::•
+        accessors
+          synthetic get v @-1
+            returnType: int
+          synthetic set v @-1
+            parameters
+              requiredPositional _v @-1
+                type: int
+            returnType: void
+      abstract class D @55
+        fields
+          synthetic v @-1
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          abstract get v @67
+            returnType: int
+''');
+  }
+
   test_class_field_implicit_type() async {
     var library = await checkLibrary('class C { var x; }');
     checkElementText(library, r'''
@@ -1996,6 +3641,169 @@
 ''');
   }
 
+  test_class_field_inferred_type_nonStatic_explicit_initialized() async {
+    var library = await checkLibrary('class C { num v = 0; }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          v @14
+            type: num
+        constructors
+          synthetic @-1
+        accessors
+          synthetic get v @-1
+            returnType: num
+          synthetic set v @-1
+            parameters
+              requiredPositional _v @-1
+                type: num
+            returnType: void
+''');
+  }
+
+  test_class_field_inferred_type_nonStatic_implicit_initialized() async {
+    var library = await checkLibrary('class C { var v = 0; }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          v @14
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          synthetic get v @-1
+            returnType: int
+          synthetic set v @-1
+            parameters
+              requiredPositional _v @-1
+                type: int
+            returnType: void
+''');
+  }
+
+  test_class_field_inferred_type_nonStatic_implicit_uninitialized() async {
+    var library = await checkLibrary(
+        'class C extends D { var v; } abstract class D { int get v; }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        supertype: D
+        fields
+          v @24
+            type: int
+        constructors
+          synthetic @-1
+            superConstructor: self::@class::D::@constructor::•
+        accessors
+          synthetic get v @-1
+            returnType: int
+          synthetic set v @-1
+            parameters
+              requiredPositional _v @-1
+                type: int
+            returnType: void
+      abstract class D @44
+        fields
+          synthetic v @-1
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          abstract get v @56
+            returnType: int
+''');
+  }
+
+  test_class_field_inferred_type_nonStatic_inherited_resolveInitializer() async {
+    var library = await checkLibrary(r'''
+const a = 0;
+abstract class A {
+  const A();
+  List<int> get f;
+}
+class B extends A {
+  const B();
+  final f = [a];
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      abstract class A @28
+        fields
+          synthetic f @-1
+            type: List<int>
+        constructors
+          const @40
+        accessors
+          abstract get f @61
+            returnType: List<int>
+      class B @72
+        supertype: A
+        fields
+          final f @107
+            type: List<int>
+            constantInitializer
+              ListLiteral
+                elements
+                  SimpleIdentifier
+                    staticElement: self::@getter::a
+                    staticType: int
+                    token: a @112
+                leftBracket: [ @111
+                rightBracket: ] @113
+                staticType: List<int>
+        constructors
+          const @94
+            superConstructor: self::@class::A::@constructor::•
+        accessors
+          synthetic get f @-1
+            returnType: List<int>
+    topLevelVariables
+      static const a @6
+        type: int
+        constantInitializer
+          IntegerLiteral
+            literal: 0 @10
+            staticType: int
+    accessors
+      synthetic static get a @-1
+        returnType: int
+''');
+  }
+
+  test_class_field_inferred_type_static_implicit_initialized() async {
+    var library = await checkLibrary('class C { static var v = 0; }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          static v @21
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          synthetic static get v @-1
+            returnType: int
+          synthetic static set v @-1
+            parameters
+              requiredPositional _v @-1
+                type: int
+            returnType: void
+''');
+  }
+
   test_class_field_inheritedContextType_double() async {
     var library = await checkLibrary('''
 abstract class A {
@@ -2031,12 +3839,139 @@
                 staticType: double
         constructors
           const @80
+            superConstructor: self::@class::A::@constructor::•
         accessors
           synthetic get foo @-1
             returnType: double
 ''');
   }
 
+  test_class_field_propagatedType_const_noDep() async {
+    var library = await checkLibrary('''
+class C {
+  static const x = 0;
+}''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          static const x @25
+            type: int
+            constantInitializer
+              IntegerLiteral
+                literal: 0 @29
+                staticType: int
+        constructors
+          synthetic @-1
+        accessors
+          synthetic static get x @-1
+            returnType: int
+''');
+  }
+
+  test_class_field_propagatedType_final_dep_inLib() async {
+    addLibrarySource('/a.dart', 'final a = 1;');
+    var library = await checkLibrary('''
+import "a.dart";
+class C {
+  final b = a / 2;
+}''');
+    checkElementText(library, r'''
+library
+  imports
+    a.dart
+  definingUnit
+    classes
+      class C @23
+        fields
+          final b @35
+            type: double
+        constructors
+          synthetic @-1
+        accessors
+          synthetic get b @-1
+            returnType: double
+''');
+  }
+
+  test_class_field_propagatedType_final_dep_inPart() async {
+    addSource('/a.dart', 'part of lib; final a = 1;');
+    var library = await checkLibrary('''
+library lib;
+part "a.dart";
+class C {
+  final b = a / 2;
+}''');
+    checkElementText(library, r'''
+library
+  name: lib
+  nameOffset: 8
+  definingUnit
+    classes
+      class C @34
+        fields
+          final b @46
+            type: double
+        constructors
+          synthetic @-1
+        accessors
+          synthetic get b @-1
+            returnType: double
+  parts
+    a.dart
+      topLevelVariables
+        static final a @19
+          type: int
+      accessors
+        synthetic static get a @-1
+          returnType: int
+''');
+  }
+
+  test_class_field_propagatedType_final_noDep_instance() async {
+    var library = await checkLibrary('''
+class C {
+  final x = 0;
+}''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          final x @18
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          synthetic get x @-1
+            returnType: int
+''');
+  }
+
+  test_class_field_propagatedType_final_noDep_static() async {
+    var library = await checkLibrary('''
+class C {
+  static final x = 0;
+}''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          static final x @25
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          synthetic static get x @-1
+            returnType: int
+''');
+  }
+
   test_class_field_static() async {
     var library = await checkLibrary('class C { static int i; }');
     checkElementText(library, r'''
@@ -2083,6 +4018,24 @@
 ''');
   }
 
+  test_class_field_static_final_untyped() async {
+    var library = await checkLibrary('class C { static final x = 0; }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          static final x @23
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          synthetic static get x @-1
+            returnType: int
+''');
+  }
+
   test_class_field_static_late() async {
     var library = await checkLibrary('class C { static late int i; }');
     checkElementText(library, r'''
@@ -2106,6 +4059,116 @@
 ''');
   }
 
+  test_class_field_type_inferred_Never() async {
+    var library = await checkLibrary(r'''
+class C {
+  var a = throw 42;
+}
+''');
+
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          a @16
+            type: Never
+        constructors
+          synthetic @-1
+        accessors
+          synthetic get a @-1
+            returnType: Never
+          synthetic set a @-1
+            parameters
+              requiredPositional _a @-1
+                type: Never
+            returnType: void
+''');
+  }
+
+  test_class_field_type_inferred_nonNullify() async {
+    addSource('/a.dart', '''
+// @dart = 2.7
+var a = 0;
+''');
+
+    var library = await checkLibrary(r'''
+import 'a.dart';
+class C {
+  var b = a;
+}
+''');
+
+    checkElementText(library, r'''
+library
+  imports
+    a.dart
+  definingUnit
+    classes
+      class C @23
+        fields
+          b @33
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          synthetic get b @-1
+            returnType: int
+          synthetic set b @-1
+            parameters
+              requiredPositional _b @-1
+                type: int
+            returnType: void
+''');
+  }
+
+  test_class_field_typed() async {
+    var library = await checkLibrary('class C { int x = 0; }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          x @14
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          synthetic get x @-1
+            returnType: int
+          synthetic set x @-1
+            parameters
+              requiredPositional _x @-1
+                type: int
+            returnType: void
+''');
+  }
+
+  test_class_field_untyped() async {
+    var library = await checkLibrary('class C { var x = 0; }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          x @14
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          synthetic get x @-1
+            returnType: int
+          synthetic set x @-1
+            parameters
+              requiredPositional _x @-1
+                type: int
+            returnType: void
+''');
+  }
+
   test_class_fields() async {
     var library = await checkLibrary('class C { int i; int j; }');
     checkElementText(library, r'''
@@ -2241,6 +4304,7 @@
             type: int
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         accessors
           synthetic get f @-1
             returnType: int
@@ -2282,6 +4346,7 @@
             type: int
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         accessors
           synthetic get f @-1
             returnType: int
@@ -2554,6 +4619,72 @@
 ''');
   }
 
+  test_class_method_async() async {
+    var library = await checkLibrary(r'''
+import 'dart:async';
+class C {
+  Future f() async {}
+}
+''');
+    checkElementText(library, r'''
+library
+  imports
+    dart:async
+  definingUnit
+    classes
+      class C @27
+        constructors
+          synthetic @-1
+        methods
+          f @40 async
+            returnType: Future<dynamic>
+''');
+  }
+
+  test_class_method_asyncStar() async {
+    var library = await checkLibrary(r'''
+import 'dart:async';
+class C {
+  Stream f() async* {}
+}
+''');
+    checkElementText(library, r'''
+library
+  imports
+    dart:async
+  definingUnit
+    classes
+      class C @27
+        constructors
+          synthetic @-1
+        methods
+          f @40 async*
+            returnType: Stream<dynamic>
+''');
+  }
+
+  test_class_method_documented() async {
+    var library = await checkLibrary('''
+class C {
+  /**
+   * Docs
+   */
+  f() {}
+}''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          synthetic @-1
+        methods
+          f @34
+            documentationComment: /**\n   * Docs\n   */
+            returnType: dynamic
+''');
+  }
+
   test_class_method_external() async {
     var library = await checkLibrary('class C { external f(); }');
     checkElementText(library, r'''
@@ -2569,6 +4700,88 @@
 ''');
   }
 
+  test_class_method_hasImplicitReturnType_false() async {
+    var library = await checkLibrary('''
+class C {
+  int m() => 0;
+}
+''');
+    var c = library.definingCompilationUnit.classes.single;
+    var m = c.methods.single;
+    expect(m.hasImplicitReturnType, isFalse);
+  }
+
+  test_class_method_hasImplicitReturnType_true() async {
+    var library = await checkLibrary('''
+class C {
+  m() => 0;
+}
+''');
+    var c = library.definingCompilationUnit.classes.single;
+    var m = c.methods.single;
+    expect(m.hasImplicitReturnType, isTrue);
+  }
+
+  test_class_method_inferred_type_nonStatic_implicit_param() async {
+    var library = await checkLibrary('class C extends D { void f(value) {} }'
+        ' abstract class D { void f(int value); }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        supertype: D
+        constructors
+          synthetic @-1
+            superConstructor: self::@class::D::@constructor::•
+        methods
+          f @25
+            parameters
+              requiredPositional value @27
+                type: int
+            returnType: void
+      abstract class D @54
+        constructors
+          synthetic @-1
+        methods
+          abstract f @63
+            parameters
+              requiredPositional value @69
+                type: int
+            returnType: void
+''');
+  }
+
+  test_class_method_inferred_type_nonStatic_implicit_return() async {
+    var library = await checkLibrary('''
+class C extends D {
+  f() => null;
+}
+abstract class D {
+  int f();
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        supertype: D
+        constructors
+          synthetic @-1
+            superConstructor: self::@class::D::@constructor::•
+        methods
+          f @22
+            returnType: int
+      abstract class D @52
+        constructors
+          synthetic @-1
+        methods
+          abstract f @62
+            returnType: int
+''');
+  }
+
   test_class_method_namedAsSupertype() async {
     var library = await checkLibrary(r'''
 class A {}
@@ -2587,6 +4800,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           A @38
             returnType: void
@@ -2647,6 +4861,106 @@
 ''');
   }
 
+  test_class_method_syncStar() async {
+    var library = await checkLibrary(r'''
+class C {
+  Iterable<int> f() sync* {
+    yield 42;
+  }
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          synthetic @-1
+        methods
+          f @26 sync*
+            returnType: Iterable<int>
+''');
+  }
+
+  test_class_method_type_parameter() async {
+    var library = await checkLibrary('class C { T f<T, U>(U u) => null; }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          synthetic @-1
+        methods
+          f @12
+            typeParameters
+              covariant T @14
+              covariant U @17
+            parameters
+              requiredPositional u @22
+                type: U
+            returnType: T
+''');
+  }
+
+  test_class_method_type_parameter_in_generic_class() async {
+    var library = await checkLibrary('''
+class C<T, U> {
+  V f<V, W>(T t, U u, W w) => null;
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        typeParameters
+          covariant T @8
+            defaultType: dynamic
+          covariant U @11
+            defaultType: dynamic
+        constructors
+          synthetic @-1
+        methods
+          f @20
+            typeParameters
+              covariant V @22
+              covariant W @25
+            parameters
+              requiredPositional t @30
+                type: T
+              requiredPositional u @35
+                type: U
+              requiredPositional w @40
+                type: W
+            returnType: V
+''');
+  }
+
+  test_class_method_type_parameter_with_function_typed_parameter() async {
+    var library = await checkLibrary('class C { void f<T, U>(T x(U u)) {} }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          synthetic @-1
+        methods
+          f @15
+            typeParameters
+              covariant T @17
+              covariant U @20
+            parameters
+              requiredPositional x @25
+                type: T Function(U)
+                parameters
+                  requiredPositional u @29
+                    type: U
+            returnType: void
+''');
+  }
+
   test_class_methods() async {
     var library = await checkLibrary('class C { f() {} g() {} }');
     checkElementText(library, r'''
@@ -2684,6 +4998,7 @@
           G
         constructors
           synthetic @-1
+            superConstructor: self::@class::D::@constructor::•
       class D @40
         constructors
           synthetic @-1
@@ -2717,6 +5032,7 @@
           C<double>
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
       class A @50
         constructors
           synthetic @-1
@@ -3154,6 +5470,153 @@
 ''');
   }
 
+  test_class_operator() async {
+    var library =
+        await checkLibrary('class C { C operator+(C other) => null; }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          synthetic @-1
+        methods
+          + @20
+            parameters
+              requiredPositional other @24
+                type: C
+            returnType: C
+''');
+  }
+
+  test_class_operator_equal() async {
+    var library = await checkLibrary('''
+class C {
+  bool operator==(Object other) => false;
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          synthetic @-1
+        methods
+          == @25
+            parameters
+              requiredPositional other @35
+                type: Object
+            returnType: bool
+''');
+  }
+
+  test_class_operator_external() async {
+    var library =
+        await checkLibrary('class C { external C operator+(C other); }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          synthetic @-1
+        methods
+          external + @29
+            parameters
+              requiredPositional other @33
+                type: C
+            returnType: C
+''');
+  }
+
+  test_class_operator_greater_equal() async {
+    var library = await checkLibrary('''
+class C {
+  bool operator>=(C other) => false;
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          synthetic @-1
+        methods
+          >= @25
+            parameters
+              requiredPositional other @30
+                type: C
+            returnType: bool
+''');
+  }
+
+  test_class_operator_index() async {
+    var library =
+        await checkLibrary('class C { bool operator[](int i) => null; }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          synthetic @-1
+        methods
+          [] @23
+            parameters
+              requiredPositional i @30
+                type: int
+            returnType: bool
+''');
+  }
+
+  test_class_operator_index_set() async {
+    var library = await checkLibrary('''
+class C {
+  void operator[]=(int i, bool v) {}
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          synthetic @-1
+        methods
+          []= @25
+            parameters
+              requiredPositional i @33
+                type: int
+              requiredPositional v @41
+                type: bool
+            returnType: void
+''');
+  }
+
+  test_class_operator_less_equal() async {
+    var library = await checkLibrary('''
+class C {
+  bool operator<=(C other) => false;
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        constructors
+          synthetic @-1
+        methods
+          <= @25
+            parameters
+              requiredPositional other @30
+                type: C
+            returnType: bool
+''');
+  }
+
   test_class_ref_nullability_none() async {
     var library = await checkLibrary('''
 class C {}
@@ -3255,6 +5718,28 @@
 ''');
   }
 
+  test_class_setter_covariant() async {
+    var library =
+        await checkLibrary('class C { void set x(covariant int value); }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          synthetic x @-1
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          abstract set x @19
+            parameters
+              requiredPositional covariant value @35
+                type: int
+            returnType: void
+''');
+  }
+
   test_class_setter_external() async {
     var library =
         await checkLibrary('class C { external void set x(int value); }');
@@ -3319,6 +5804,140 @@
 ''');
   }
 
+  test_class_setter_inferred_type_conflictingInheritance() async {
+    var library = await checkLibrary('''
+class A {
+  int t;
+}
+class B extends A {
+  double t;
+}
+class C extends A implements B {
+}
+class D extends C {
+  void set t(p) {}
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @6
+        fields
+          t @16
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          synthetic get t @-1
+            returnType: int
+          synthetic set t @-1
+            parameters
+              requiredPositional _t @-1
+                type: int
+            returnType: void
+      class B @27
+        supertype: A
+        fields
+          t @50
+            type: double
+        constructors
+          synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
+        accessors
+          synthetic get t @-1
+            returnType: double
+          synthetic set t @-1
+            parameters
+              requiredPositional _t @-1
+                type: double
+            returnType: void
+      class C @61
+        supertype: A
+        interfaces
+          B
+        constructors
+          synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
+      class D @96
+        supertype: C
+        fields
+          synthetic t @-1
+            type: dynamic
+        constructors
+          synthetic @-1
+            superConstructor: self::@class::C::@constructor::•
+        accessors
+          set t @121
+            parameters
+              requiredPositional p @123
+                type: dynamic
+            returnType: void
+''');
+  }
+
+  test_class_setter_inferred_type_nonStatic_implicit_param() async {
+    var library =
+        await checkLibrary('class C extends D { void set f(value) {} }'
+            ' abstract class D { void set f(int value); }');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        supertype: D
+        fields
+          synthetic f @-1
+            type: int
+        constructors
+          synthetic @-1
+            superConstructor: self::@class::D::@constructor::•
+        accessors
+          set f @29
+            parameters
+              requiredPositional value @31
+                type: int
+            returnType: void
+      abstract class D @58
+        fields
+          synthetic f @-1
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          abstract set f @71
+            parameters
+              requiredPositional value @77
+                type: int
+            returnType: void
+''');
+  }
+
+  test_class_setter_inferred_type_static_implicit_return() async {
+    var library = await checkLibrary('''
+class C {
+  static set f(int value) {}
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class C @6
+        fields
+          synthetic static f @-1
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          static set f @23
+            parameters
+              requiredPositional value @29
+                type: int
+            returnType: void
+''');
+  }
+
   test_class_setter_invalid_named_parameter() async {
     var library = await checkLibrary('class C { void set x({a}) {} }');
     checkElementText(library, r'''
@@ -3495,6 +6114,7 @@
         supertype: D
         constructors
           synthetic @-1
+            superConstructor: self::@class::D::@constructor::•
       class D @27
         constructors
           synthetic @-1
@@ -3514,6 +6134,9 @@
         supertype: D<int, double>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::D::@constructor::•
+              substitution: {T1: int, T2: double}
       class D @40
         typeParameters
           covariant T1 @42
@@ -3544,6 +6167,9 @@
         supertype: A<B>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {T: B}
 ''');
   }
 
@@ -3559,7 +6185,7 @@
 ''');
   }
 
-  test_class_type_parameters() async {
+  test_class_typeParameters() async {
     var library = await checkLibrary('class C<T, U> {}');
     checkElementText(library, r'''
 library
@@ -3576,7 +6202,7 @@
 ''');
   }
 
-  test_class_type_parameters_bound() async {
+  test_class_typeParameters_bound() async {
     var library = await checkLibrary('''
 class C<T extends Object, U extends D> {}
 class D {}
@@ -3601,7 +6227,7 @@
 ''');
   }
 
-  test_class_type_parameters_cycle_1of1() async {
+  test_class_typeParameters_cycle_1of1() async {
     var library = await checkLibrary('class C<T extends T> {}');
     checkElementText(library, r'''
 library
@@ -3617,7 +6243,7 @@
 ''');
   }
 
-  test_class_type_parameters_cycle_2of3() async {
+  test_class_typeParameters_cycle_2of3() async {
     var library = await checkLibrary(r'''
 class C<T extends V, U, V extends T> {}
 ''');
@@ -3640,42 +6266,6 @@
 ''');
   }
 
-  test_class_type_parameters_f_bound_complex() async {
-    var library = await checkLibrary('class C<T extends List<U>, U> {}');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      notSimplyBounded class C @6
-        typeParameters
-          covariant T @8
-            bound: List<U>
-            defaultType: List<dynamic>
-          covariant U @27
-            defaultType: dynamic
-        constructors
-          synthetic @-1
-''');
-  }
-
-  test_class_type_parameters_f_bound_simple() async {
-    var library = await checkLibrary('class C<T extends U, U> {}');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      notSimplyBounded class C @6
-        typeParameters
-          covariant T @8
-            bound: U
-            defaultType: dynamic
-          covariant U @21
-            defaultType: dynamic
-        constructors
-          synthetic @-1
-''');
-  }
-
   test_class_typeParameters_defaultType_cycle_genericFunctionType() async {
     var library = await checkLibrary(r'''
 class A<T extends void Function(A)> {}
@@ -4069,6 +6659,42 @@
 ''');
   }
 
+  test_class_typeParameters_f_bound_complex() async {
+    var library = await checkLibrary('class C<T extends List<U>, U> {}');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      notSimplyBounded class C @6
+        typeParameters
+          covariant T @8
+            bound: List<U>
+            defaultType: List<dynamic>
+          covariant U @27
+            defaultType: dynamic
+        constructors
+          synthetic @-1
+''');
+  }
+
+  test_class_typeParameters_f_bound_simple() async {
+    var library = await checkLibrary('class C<T extends U, U> {}');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      notSimplyBounded class C @6
+        typeParameters
+          covariant T @8
+            bound: U
+            defaultType: dynamic
+          covariant U @21
+            defaultType: dynamic
+        constructors
+          synthetic @-1
+''');
+  }
+
   test_class_typeParameters_variance_contravariant() async {
     var library = await checkLibrary('class C<in T> {}');
     checkElementText(library, r'''
@@ -4133,6 +6759,789 @@
 ''');
   }
 
+  test_classAlias() async {
+    var library = await checkLibrary('''
+class C = D with E, F, G;
+class D {}
+class E {}
+class F {}
+class G {}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class alias C @6
+        supertype: D
+        mixins
+          E
+          F
+          G
+        constructors
+          synthetic @-1
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                staticElement: self::@class::D::@constructor::•
+                superKeyword: super @0
+            superConstructor: self::@class::D::@constructor::•
+      class D @32
+        constructors
+          synthetic @-1
+      class E @43
+        constructors
+          synthetic @-1
+      class F @54
+        constructors
+          synthetic @-1
+      class G @65
+        constructors
+          synthetic @-1
+''');
+  }
+
+  test_classAlias_abstract() async {
+    var library = await checkLibrary('''
+abstract class C = D with E;
+class D {}
+class E {}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      abstract class alias C @15
+        supertype: D
+        mixins
+          E
+        constructors
+          synthetic @-1
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                staticElement: self::@class::D::@constructor::•
+                superKeyword: super @0
+            superConstructor: self::@class::D::@constructor::•
+      class D @35
+        constructors
+          synthetic @-1
+      class E @46
+        constructors
+          synthetic @-1
+''');
+  }
+
+  test_classAlias_documented() async {
+    var library = await checkLibrary('''
+/**
+ * Docs
+ */
+class C = D with E;
+
+class D {}
+class E {}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class alias C @22
+        documentationComment: /**\n * Docs\n */
+        supertype: D
+        mixins
+          E
+        constructors
+          synthetic @-1
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                staticElement: self::@class::D::@constructor::•
+                superKeyword: super @0
+            superConstructor: self::@class::D::@constructor::•
+      class D @43
+        constructors
+          synthetic @-1
+      class E @54
+        constructors
+          synthetic @-1
+''');
+  }
+
+  test_classAlias_documented_tripleSlash() async {
+    var library = await checkLibrary('''
+/// aaa
+/// b
+/// cc
+class C = D with E;
+
+class D {}
+class E {}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class alias C @27
+        documentationComment: /// aaa\n/// b\n/// cc
+        supertype: D
+        mixins
+          E
+        constructors
+          synthetic @-1
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                staticElement: self::@class::D::@constructor::•
+                superKeyword: super @0
+            superConstructor: self::@class::D::@constructor::•
+      class D @48
+        constructors
+          synthetic @-1
+      class E @59
+        constructors
+          synthetic @-1
+''');
+  }
+
+  test_classAlias_documented_withLeadingNonDocumentation() async {
+    var library = await checkLibrary('''
+// Extra comment so doc comment offset != 0
+/**
+ * Docs
+ */
+class C = D with E;
+
+class D {}
+class E {}''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class alias C @66
+        documentationComment: /**\n * Docs\n */
+        supertype: D
+        mixins
+          E
+        constructors
+          synthetic @-1
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                staticElement: self::@class::D::@constructor::•
+                superKeyword: super @0
+            superConstructor: self::@class::D::@constructor::•
+      class D @87
+        constructors
+          synthetic @-1
+      class E @98
+        constructors
+          synthetic @-1
+''');
+  }
+
+  test_classAlias_generic() async {
+    var library = await checkLibrary('''
+class Z = A with B<int>, C<double>;
+class A {}
+class B<B1> {}
+class C<C1> {}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class alias Z @6
+        supertype: A
+        mixins
+          B<int>
+          C<double>
+        constructors
+          synthetic @-1
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                staticElement: self::@class::A::@constructor::•
+                superKeyword: super @0
+            superConstructor: self::@class::A::@constructor::•
+      class A @42
+        constructors
+          synthetic @-1
+      class B @53
+        typeParameters
+          covariant B1 @55
+            defaultType: dynamic
+        constructors
+          synthetic @-1
+      class C @68
+        typeParameters
+          covariant C1 @70
+            defaultType: dynamic
+        constructors
+          synthetic @-1
+''');
+  }
+
+  test_classAlias_notSimplyBounded_self() async {
+    var library = await checkLibrary('''
+class C<T extends C> = D with E;
+class D {}
+class E {}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      notSimplyBounded class alias C @6
+        typeParameters
+          covariant T @8
+            bound: C<dynamic>
+            defaultType: dynamic
+        supertype: D
+        mixins
+          E
+        constructors
+          synthetic @-1
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                staticElement: self::@class::D::@constructor::•
+                superKeyword: super @0
+            superConstructor: self::@class::D::@constructor::•
+      class D @39
+        constructors
+          synthetic @-1
+      class E @50
+        constructors
+          synthetic @-1
+''');
+  }
+
+  test_classAlias_notSimplyBounded_simple_no_type_parameter_bound() async {
+    // If no bounds are specified, then the class is simply bounded by syntax
+    // alone, so there is no reason to assign it a slot.
+    var library = await checkLibrary('''
+class C<T> = D with E;
+class D {}
+class E {}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class alias C @6
+        typeParameters
+          covariant T @8
+            defaultType: dynamic
+        supertype: D
+        mixins
+          E
+        constructors
+          synthetic @-1
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                staticElement: self::@class::D::@constructor::•
+                superKeyword: super @0
+            superConstructor: self::@class::D::@constructor::•
+      class D @29
+        constructors
+          synthetic @-1
+      class E @40
+        constructors
+          synthetic @-1
+''');
+  }
+
+  test_classAlias_notSimplyBounded_simple_non_generic() async {
+    // If no type parameters are specified, then the class is simply bounded, so
+    // there is no reason to assign it a slot.
+    var library = await checkLibrary('''
+class C = D with E;
+class D {}
+class E {}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class alias C @6
+        supertype: D
+        mixins
+          E
+        constructors
+          synthetic @-1
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                staticElement: self::@class::D::@constructor::•
+                superKeyword: super @0
+            superConstructor: self::@class::D::@constructor::•
+      class D @26
+        constructors
+          synthetic @-1
+      class E @37
+        constructors
+          synthetic @-1
+''');
+  }
+
+  test_classAlias_with_const_constructors() async {
+    testFile = convertPath('/home/test/lib/test.dart');
+    addLibrarySource('/home/test/lib/a.dart', r'''
+class Base {
+  const Base._priv();
+  const Base();
+  const Base.named();
+}
+''');
+    var library = await checkLibrary('''
+import "a.dart";
+class M {}
+class MixinApp = Base with M;
+''');
+    checkElementText(library, r'''
+library
+  imports
+    package:test/a.dart
+  definingUnit
+    classes
+      class M @23
+        constructors
+          synthetic @-1
+      class alias MixinApp @34
+        supertype: Base
+        mixins
+          M
+        constructors
+          synthetic const @-1
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                staticElement: package:test/a.dart::@class::Base::@constructor::•
+                superKeyword: super @0
+            superConstructor: package:test/a.dart::@class::Base::@constructor::•
+          synthetic const named @-1
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                constructorName: SimpleIdentifier
+                  staticElement: package:test/a.dart::@class::Base::@constructor::named
+                  staticType: null
+                  token: named @-1
+                period: . @0
+                staticElement: package:test/a.dart::@class::Base::@constructor::named
+                superKeyword: super @0
+            superConstructor: package:test/a.dart::@class::Base::@constructor::named
+''');
+  }
+
+  test_classAlias_with_forwarding_constructors() async {
+    testFile = convertPath('/home/test/lib/test.dart');
+    addLibrarySource('/home/test/lib/a.dart', r'''
+class Base {
+  bool x = true;
+  Base._priv();
+  Base();
+  Base.noArgs();
+  Base.requiredArg(x);
+  Base.positionalArg([bool x = true]);
+  Base.positionalArg2([this.x = true]);
+  Base.namedArg({int x = 42});
+  Base.namedArg2({this.x = true});
+  factory Base.fact() => Base();
+  factory Base.fact2() = Base.noArgs;
+}
+''');
+    var library = await checkLibrary('''
+import "a.dart";
+class M {}
+class MixinApp = Base with M;
+''');
+    checkElementText(library, r'''
+library
+  imports
+    package:test/a.dart
+  definingUnit
+    classes
+      class M @23
+        constructors
+          synthetic @-1
+      class alias MixinApp @34
+        supertype: Base
+        mixins
+          M
+        constructors
+          synthetic @-1
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                staticElement: package:test/a.dart::@class::Base::@constructor::•
+                superKeyword: super @0
+            superConstructor: package:test/a.dart::@class::Base::@constructor::•
+          synthetic noArgs @-1
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                constructorName: SimpleIdentifier
+                  staticElement: package:test/a.dart::@class::Base::@constructor::noArgs
+                  staticType: null
+                  token: noArgs @-1
+                period: . @0
+                staticElement: package:test/a.dart::@class::Base::@constructor::noArgs
+                superKeyword: super @0
+            superConstructor: package:test/a.dart::@class::Base::@constructor::noArgs
+          synthetic requiredArg @-1
+            parameters
+              requiredPositional x @-1
+                type: dynamic
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    SimpleIdentifier
+                      staticElement: x@-1
+                      staticType: dynamic
+                      token: x @-1
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                constructorName: SimpleIdentifier
+                  staticElement: package:test/a.dart::@class::Base::@constructor::requiredArg
+                  staticType: null
+                  token: requiredArg @-1
+                period: . @0
+                staticElement: package:test/a.dart::@class::Base::@constructor::requiredArg
+                superKeyword: super @0
+            superConstructor: package:test/a.dart::@class::Base::@constructor::requiredArg
+          synthetic positionalArg @-1
+            parameters
+              optionalPositional x @-1
+                type: bool
+                constantInitializer
+                  BooleanLiteral
+                    literal: true @127
+                    staticType: bool
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    SimpleIdentifier
+                      staticElement: x@-1
+                      staticType: bool
+                      token: x @-1
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                constructorName: SimpleIdentifier
+                  staticElement: package:test/a.dart::@class::Base::@constructor::positionalArg
+                  staticType: null
+                  token: positionalArg @-1
+                period: . @0
+                staticElement: package:test/a.dart::@class::Base::@constructor::positionalArg
+                superKeyword: super @0
+            superConstructor: package:test/a.dart::@class::Base::@constructor::positionalArg
+          synthetic positionalArg2 @-1
+            parameters
+              optionalPositional final x @-1
+                type: bool
+                constantInitializer
+                  BooleanLiteral
+                    literal: true @167
+                    staticType: bool
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    SimpleIdentifier
+                      staticElement: x@-1
+                      staticType: bool
+                      token: x @-1
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                constructorName: SimpleIdentifier
+                  staticElement: package:test/a.dart::@class::Base::@constructor::positionalArg2
+                  staticType: null
+                  token: positionalArg2 @-1
+                period: . @0
+                staticElement: package:test/a.dart::@class::Base::@constructor::positionalArg2
+                superKeyword: super @0
+            superConstructor: package:test/a.dart::@class::Base::@constructor::positionalArg2
+          synthetic namedArg @-1
+            parameters
+              optionalNamed x @-1
+                type: int
+                constantInitializer
+                  IntegerLiteral
+                    literal: 42 @200
+                    staticType: int
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    SimpleIdentifier
+                      staticElement: x@-1
+                      staticType: int
+                      token: x @-1
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                constructorName: SimpleIdentifier
+                  staticElement: package:test/a.dart::@class::Base::@constructor::namedArg
+                  staticType: null
+                  token: namedArg @-1
+                period: . @0
+                staticElement: package:test/a.dart::@class::Base::@constructor::namedArg
+                superKeyword: super @0
+            superConstructor: package:test/a.dart::@class::Base::@constructor::namedArg
+          synthetic namedArg2 @-1
+            parameters
+              optionalNamed final x @-1
+                type: bool
+                constantInitializer
+                  BooleanLiteral
+                    literal: true @233
+                    staticType: bool
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    SimpleIdentifier
+                      staticElement: x@-1
+                      staticType: bool
+                      token: x @-1
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                constructorName: SimpleIdentifier
+                  staticElement: package:test/a.dart::@class::Base::@constructor::namedArg2
+                  staticType: null
+                  token: namedArg2 @-1
+                period: . @0
+                staticElement: package:test/a.dart::@class::Base::@constructor::namedArg2
+                superKeyword: super @0
+            superConstructor: package:test/a.dart::@class::Base::@constructor::namedArg2
+''');
+  }
+
+  test_classAlias_with_forwarding_constructors_type_substitution() async {
+    var library = await checkLibrary('''
+class Base<T> {
+  Base.ctor(T t, List<T> l);
+}
+class M {}
+class MixinApp = Base with M;
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class Base @6
+        typeParameters
+          covariant T @11
+            defaultType: dynamic
+        constructors
+          ctor @23
+            periodOffset: 22
+            nameEnd: 27
+            parameters
+              requiredPositional t @30
+                type: T
+              requiredPositional l @41
+                type: List<T>
+      class M @53
+        constructors
+          synthetic @-1
+      class alias MixinApp @64
+        supertype: Base<dynamic>
+        mixins
+          M
+        constructors
+          synthetic ctor @-1
+            parameters
+              requiredPositional t @-1
+                type: dynamic
+              requiredPositional l @-1
+                type: List<dynamic>
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    SimpleIdentifier
+                      staticElement: t@-1
+                      staticType: dynamic
+                      token: t @-1
+                    SimpleIdentifier
+                      staticElement: l@-1
+                      staticType: List<dynamic>
+                      token: l @-1
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                constructorName: SimpleIdentifier
+                  staticElement: self::@class::Base::@constructor::ctor
+                  staticType: null
+                  token: ctor @-1
+                period: . @0
+                staticElement: self::@class::Base::@constructor::ctor
+                superKeyword: super @0
+            superConstructor: ConstructorMember
+              base: self::@class::Base::@constructor::ctor
+              substitution: {T: dynamic}
+''');
+  }
+
+  test_classAlias_with_forwarding_constructors_type_substitution_complex() async {
+    var library = await checkLibrary('''
+class Base<T> {
+  Base.ctor(T t, List<T> l);
+}
+class M {}
+class MixinApp<U> = Base<List<U>> with M;
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class Base @6
+        typeParameters
+          covariant T @11
+            defaultType: dynamic
+        constructors
+          ctor @23
+            periodOffset: 22
+            nameEnd: 27
+            parameters
+              requiredPositional t @30
+                type: T
+              requiredPositional l @41
+                type: List<T>
+      class M @53
+        constructors
+          synthetic @-1
+      class alias MixinApp @64
+        typeParameters
+          covariant U @73
+            defaultType: dynamic
+        supertype: Base<List<U>>
+        mixins
+          M
+        constructors
+          synthetic ctor @-1
+            parameters
+              requiredPositional t @-1
+                type: List<U>
+              requiredPositional l @-1
+                type: List<List<U>>
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  arguments
+                    SimpleIdentifier
+                      staticElement: t@-1
+                      staticType: List<U>
+                      token: t @-1
+                    SimpleIdentifier
+                      staticElement: l@-1
+                      staticType: List<List<U>>
+                      token: l @-1
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                constructorName: SimpleIdentifier
+                  staticElement: self::@class::Base::@constructor::ctor
+                  staticType: null
+                  token: ctor @-1
+                period: . @0
+                staticElement: self::@class::Base::@constructor::ctor
+                superKeyword: super @0
+            superConstructor: ConstructorMember
+              base: self::@class::Base::@constructor::ctor
+              substitution: {T: List<U>}
+''');
+  }
+
+  test_classAlias_with_mixin_members() async {
+    var library = await checkLibrary('''
+class C = D with E;
+class D {}
+class E {
+  int get a => null;
+  void set b(int i) {}
+  void f() {}
+  int x;
+}''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class alias C @6
+        supertype: D
+        mixins
+          E
+        constructors
+          synthetic @-1
+            constantInitializers
+              SuperConstructorInvocation
+                argumentList: ArgumentList
+                  leftParenthesis: ( @0
+                  rightParenthesis: ) @0
+                staticElement: self::@class::D::@constructor::•
+                superKeyword: super @0
+            superConstructor: self::@class::D::@constructor::•
+      class D @26
+        constructors
+          synthetic @-1
+      class E @37
+        fields
+          x @105
+            type: int
+          synthetic a @-1
+            type: int
+          synthetic b @-1
+            type: int
+        constructors
+          synthetic @-1
+        accessors
+          synthetic get x @-1
+            returnType: int
+          synthetic set x @-1
+            parameters
+              requiredPositional _x @-1
+                type: int
+            returnType: void
+          get a @51
+            returnType: int
+          set b @73
+            parameters
+              requiredPositional i @79
+                type: int
+            returnType: void
+        methods
+          f @92
+            returnType: void
+''');
+  }
+
   test_classes() async {
     var library = await checkLibrary('class C {} class D {}');
     checkElementText(library, r'''
@@ -4775,8 +8184,7 @@
       enum E @5
         codeOffset: 0
         codeLength: 26
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -6695,6 +10103,9 @@
         supertype: P<T>
         constructors
           const @64
+            superConstructor: ConstructorMember
+              base: self::@class::P::@constructor::•
+              substitution: {T: T}
       class P2 @79
         typeParameters
           covariant T @82
@@ -6702,6 +10113,9 @@
         supertype: P<T>
         constructors
           const @108
+            superConstructor: ConstructorMember
+              base: self::@class::P::@constructor::•
+              substitution: {T: T}
     topLevelVariables
       static const values @131
         type: List<P<dynamic>>
@@ -9940,8 +13354,7 @@
           synthetic @-1
     enums
       enum E @30
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -12159,8 +15572,7 @@
   definingUnit
     enums
       enum E @5
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -12213,8 +15625,7 @@
   definingUnit
     enums
       enum E @5
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -12308,1670 +15719,6 @@
 ''');
   }
 
-  test_constructor_documented() async {
-    var library = await checkLibrary('''
-class C {
-  /**
-   * Docs
-   */
-  C();
-}''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          @34
-            documentationComment: /**\n   * Docs\n   */
-''');
-  }
-
-  test_constructor_initializers_assertInvocation() async {
-    var library = await checkLibrary('''
-class C {
-  const C(int x) : assert(x >= 42);
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          const @18
-            parameters
-              requiredPositional x @24
-                type: int
-            constantInitializers
-              AssertInitializer
-                assertKeyword: assert @29
-                condition: BinaryExpression
-                  leftOperand: SimpleIdentifier
-                    staticElement: x@24
-                    staticType: int
-                    token: x @36
-                  operator: >= @38
-                  rightOperand: IntegerLiteral
-                    literal: 42 @41
-                    staticType: int
-                  staticElement: dart:core::@class::num::@method::>=
-                  staticInvokeType: bool Function(num)
-                  staticType: bool
-                leftParenthesis: ( @35
-                rightParenthesis: ) @43
-''');
-  }
-
-  test_constructor_initializers_assertInvocation_message() async {
-    var library = await checkLibrary('''
-class C {
-  const C(int x) : assert(x >= 42, 'foo');
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          const @18
-            parameters
-              requiredPositional x @24
-                type: int
-            constantInitializers
-              AssertInitializer
-                assertKeyword: assert @29
-                condition: BinaryExpression
-                  leftOperand: SimpleIdentifier
-                    staticElement: x@24
-                    staticType: int
-                    token: x @36
-                  operator: >= @38
-                  rightOperand: IntegerLiteral
-                    literal: 42 @41
-                    staticType: int
-                  staticElement: dart:core::@class::num::@method::>=
-                  staticInvokeType: bool Function(num)
-                  staticType: bool
-                leftParenthesis: ( @35
-                message: SimpleStringLiteral
-                  literal: 'foo' @45
-                rightParenthesis: ) @50
-''');
-  }
-
-  test_constructor_initializers_field() async {
-    var library = await checkLibrary('''
-class C {
-  final x;
-  const C() : x = 42;
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          final x @18
-            type: dynamic
-        constructors
-          const @29
-            constantInitializers
-              ConstructorFieldInitializer
-                equals: = @37
-                expression: IntegerLiteral
-                  literal: 42 @39
-                  staticType: int
-                fieldName: SimpleIdentifier
-                  staticElement: self::@class::C::@field::x
-                  staticType: null
-                  token: x @35
-        accessors
-          synthetic get x @-1
-            returnType: dynamic
-''');
-  }
-
-  test_constructor_initializers_field_notConst() async {
-    var library = await checkLibrary('''
-class C {
-  final x;
-  const C() : x = foo();
-}
-int foo() => 42;
-''', allowErrors: true);
-    // It is OK to keep non-constant initializers.
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          final x @18
-            type: dynamic
-        constructors
-          const @29
-            constantInitializers
-              ConstructorFieldInitializer
-                equals: = @37
-                expression: MethodInvocation
-                  argumentList: ArgumentList
-                    leftParenthesis: ( @42
-                    rightParenthesis: ) @43
-                  methodName: SimpleIdentifier
-                    staticElement: self::@function::foo
-                    staticType: int Function()
-                    token: foo @39
-                  staticInvokeType: int Function()
-                  staticType: int
-                fieldName: SimpleIdentifier
-                  staticElement: self::@class::C::@field::x
-                  staticType: null
-                  token: x @35
-        accessors
-          synthetic get x @-1
-            returnType: dynamic
-    functions
-      foo @52
-        returnType: int
-''');
-  }
-
-  test_constructor_initializers_field_optionalPositionalParameter() async {
-    var library = await checkLibrary('''
-class A {
-  final int _f;
-  const A([int f = 0]) : _f = f;
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class A @6
-        fields
-          final _f @22
-            type: int
-        constructors
-          const @34
-            parameters
-              optionalPositional f @41
-                type: int
-                constantInitializer
-                  IntegerLiteral
-                    literal: 0 @45
-                    staticType: int
-            constantInitializers
-              ConstructorFieldInitializer
-                equals: = @54
-                expression: SimpleIdentifier
-                  staticElement: self::@class::A::@constructor::•::@parameter::f
-                  staticType: int
-                  token: f @56
-                fieldName: SimpleIdentifier
-                  staticElement: self::@class::A::@field::_f
-                  staticType: null
-                  token: _f @51
-        accessors
-          synthetic get _f @-1
-            returnType: int
-''');
-  }
-
-  test_constructor_initializers_field_withParameter() async {
-    var library = await checkLibrary('''
-class C {
-  final x;
-  const C(int p) : x = 1 + p;
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          final x @18
-            type: dynamic
-        constructors
-          const @29
-            parameters
-              requiredPositional p @35
-                type: int
-            constantInitializers
-              ConstructorFieldInitializer
-                equals: = @42
-                expression: BinaryExpression
-                  leftOperand: IntegerLiteral
-                    literal: 1 @44
-                    staticType: int
-                  operator: + @46
-                  rightOperand: SimpleIdentifier
-                    staticElement: p@35
-                    staticType: int
-                    token: p @48
-                  staticElement: dart:core::@class::num::@method::+
-                  staticInvokeType: num Function(num)
-                  staticType: int
-                fieldName: SimpleIdentifier
-                  staticElement: self::@class::C::@field::x
-                  staticType: null
-                  token: x @40
-        accessors
-          synthetic get x @-1
-            returnType: dynamic
-''');
-  }
-
-  test_constructor_initializers_genericFunctionType() async {
-    var library = await checkLibrary('''
-class A<T> {
-  const A();
-}
-class B {
-  const B(dynamic x);
-  const B.f()
-   : this(A<Function()>());
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class A @6
-        typeParameters
-          covariant T @8
-            defaultType: dynamic
-        constructors
-          const @21
-      class B @34
-        constructors
-          const @46
-            parameters
-              requiredPositional x @56
-                type: dynamic
-          const f @70
-            periodOffset: 69
-            nameEnd: 71
-            constantInitializers
-              RedirectingConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    InstanceCreationExpression
-                      argumentList: ArgumentList
-                        leftParenthesis: ( @97
-                        rightParenthesis: ) @98
-                      constructorName: ConstructorName
-                        staticElement: ConstructorMember
-                          base: self::@class::A::@constructor::•
-                          substitution: {T: dynamic Function()}
-                        type: NamedType
-                          name: SimpleIdentifier
-                            staticElement: self::@class::A
-                            staticType: null
-                            token: A @84
-                          type: A<dynamic Function()>
-                          typeArguments: TypeArgumentList
-                            arguments
-                              GenericFunctionType
-                                declaredElement: GenericFunctionTypeElement
-                                  parameters
-                                  returnType: dynamic
-                                  type: dynamic Function()
-                                functionKeyword: Function @86
-                                parameters: FormalParameterList
-                                  leftParenthesis: ( @94
-                                  rightParenthesis: ) @95
-                                type: dynamic Function()
-                            leftBracket: < @85
-                            rightBracket: > @96
-                      staticType: A<dynamic Function()>
-                  leftParenthesis: ( @83
-                  rightParenthesis: ) @99
-                staticElement: self::@class::B::@constructor::•
-                thisKeyword: this @79
-            redirectedConstructor: self::@class::B::@constructor::•
-''');
-  }
-
-  test_constructor_initializers_superInvocation_argumentContextType() async {
-    var library = await checkLibrary('''
-class A {
-  const A(List<String> values);
-}
-class B extends A {
-  const B() : super(const []);
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class A @6
-        constructors
-          const @18
-            parameters
-              requiredPositional values @33
-                type: List<String>
-      class B @50
-        supertype: A
-        constructors
-          const @72
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    ListLiteral
-                      constKeyword: const @84
-                      leftBracket: [ @90
-                      rightBracket: ] @91
-                      staticType: List<String>
-                  leftParenthesis: ( @83
-                  rightParenthesis: ) @92
-                staticElement: self::@class::A::@constructor::•
-                superKeyword: super @78
-''');
-  }
-
-  test_constructor_initializers_superInvocation_named() async {
-    var library = await checkLibrary('''
-class A {
-  const A.aaa(int p);
-}
-class C extends A {
-  const C() : super.aaa(42);
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class A @6
-        constructors
-          const aaa @20
-            periodOffset: 19
-            nameEnd: 23
-            parameters
-              requiredPositional p @28
-                type: int
-      class C @40
-        supertype: A
-        constructors
-          const @62
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    IntegerLiteral
-                      literal: 42 @78
-                      staticType: int
-                  leftParenthesis: ( @77
-                  rightParenthesis: ) @80
-                constructorName: SimpleIdentifier
-                  staticElement: self::@class::A::@constructor::aaa
-                  staticType: null
-                  token: aaa @74
-                period: . @73
-                staticElement: self::@class::A::@constructor::aaa
-                superKeyword: super @68
-''');
-  }
-
-  test_constructor_initializers_superInvocation_named_underscore() async {
-    var library = await checkLibrary('''
-class A {
-  const A._();
-}
-class B extends A {
-  const B() : super._();
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class A @6
-        constructors
-          const _ @20
-            periodOffset: 19
-            nameEnd: 21
-      class B @33
-        supertype: A
-        constructors
-          const @55
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  leftParenthesis: ( @68
-                  rightParenthesis: ) @69
-                constructorName: SimpleIdentifier
-                  staticElement: self::@class::A::@constructor::_
-                  staticType: null
-                  token: _ @67
-                period: . @66
-                staticElement: self::@class::A::@constructor::_
-                superKeyword: super @61
-''');
-  }
-
-  test_constructor_initializers_superInvocation_namedExpression() async {
-    var library = await checkLibrary('''
-class A {
-  const A.aaa(a, {int b});
-}
-class C extends A {
-  const C() : super.aaa(1, b: 2);
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class A @6
-        constructors
-          const aaa @20
-            periodOffset: 19
-            nameEnd: 23
-            parameters
-              requiredPositional a @24
-                type: dynamic
-              optionalNamed b @32
-                type: int
-      class C @45
-        supertype: A
-        constructors
-          const @67
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    IntegerLiteral
-                      literal: 1 @83
-                      staticType: int
-                    NamedExpression
-                      name: Label
-                        label: SimpleIdentifier
-                          staticElement: self::@class::A::@constructor::aaa::@parameter::b
-                          staticType: null
-                          token: b @86
-                      expression: IntegerLiteral
-                        literal: 2 @89
-                        staticType: int
-                  leftParenthesis: ( @82
-                  rightParenthesis: ) @90
-                constructorName: SimpleIdentifier
-                  staticElement: self::@class::A::@constructor::aaa
-                  staticType: null
-                  token: aaa @79
-                period: . @78
-                staticElement: self::@class::A::@constructor::aaa
-                superKeyword: super @73
-''');
-  }
-
-  test_constructor_initializers_superInvocation_unnamed() async {
-    var library = await checkLibrary('''
-class A {
-  const A(int p);
-}
-class C extends A {
-  const C.ccc() : super(42);
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class A @6
-        constructors
-          const @18
-            parameters
-              requiredPositional p @24
-                type: int
-      class C @36
-        supertype: A
-        constructors
-          const ccc @60
-            periodOffset: 59
-            nameEnd: 63
-            constantInitializers
-              SuperConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    IntegerLiteral
-                      literal: 42 @74
-                      staticType: int
-                  leftParenthesis: ( @73
-                  rightParenthesis: ) @76
-                staticElement: self::@class::A::@constructor::•
-                superKeyword: super @68
-''');
-  }
-
-  test_constructor_initializers_thisInvocation_argumentContextType() async {
-    var library = await checkLibrary('''
-class A {
-  const A(List<String> values);
-  const A.empty() : this(const []);
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class A @6
-        constructors
-          const @18
-            parameters
-              requiredPositional values @33
-                type: List<String>
-          const empty @52
-            periodOffset: 51
-            nameEnd: 57
-            constantInitializers
-              RedirectingConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    ListLiteral
-                      constKeyword: const @67
-                      leftBracket: [ @73
-                      rightBracket: ] @74
-                      staticType: List<String>
-                  leftParenthesis: ( @66
-                  rightParenthesis: ) @75
-                staticElement: self::@class::A::@constructor::•
-                thisKeyword: this @62
-            redirectedConstructor: self::@class::A::@constructor::•
-''');
-  }
-
-  test_constructor_initializers_thisInvocation_named() async {
-    var library = await checkLibrary('''
-class C {
-  const C() : this.named(1, 'bbb');
-  const C.named(int a, String b);
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          const @18
-            constantInitializers
-              RedirectingConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    IntegerLiteral
-                      literal: 1 @35
-                      staticType: int
-                    SimpleStringLiteral
-                      literal: 'bbb' @38
-                  leftParenthesis: ( @34
-                  rightParenthesis: ) @43
-                constructorName: SimpleIdentifier
-                  staticElement: self::@class::C::@constructor::named
-                  staticType: null
-                  token: named @29
-                period: . @28
-                staticElement: self::@class::C::@constructor::named
-                thisKeyword: this @24
-            redirectedConstructor: self::@class::C::@constructor::named
-          const named @56
-            periodOffset: 55
-            nameEnd: 61
-            parameters
-              requiredPositional a @66
-                type: int
-              requiredPositional b @76
-                type: String
-''');
-  }
-
-  test_constructor_initializers_thisInvocation_namedExpression() async {
-    var library = await checkLibrary('''
-class C {
-  const C() : this.named(1, b: 2);
-  const C.named(a, {int b});
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          const @18
-            constantInitializers
-              RedirectingConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    IntegerLiteral
-                      literal: 1 @35
-                      staticType: int
-                    NamedExpression
-                      name: Label
-                        label: SimpleIdentifier
-                          staticElement: self::@class::C::@constructor::named::@parameter::b
-                          staticType: null
-                          token: b @38
-                      expression: IntegerLiteral
-                        literal: 2 @41
-                        staticType: int
-                  leftParenthesis: ( @34
-                  rightParenthesis: ) @42
-                constructorName: SimpleIdentifier
-                  staticElement: self::@class::C::@constructor::named
-                  staticType: null
-                  token: named @29
-                period: . @28
-                staticElement: self::@class::C::@constructor::named
-                thisKeyword: this @24
-            redirectedConstructor: self::@class::C::@constructor::named
-          const named @55
-            periodOffset: 54
-            nameEnd: 60
-            parameters
-              requiredPositional a @61
-                type: dynamic
-              optionalNamed b @69
-                type: int
-''');
-  }
-
-  test_constructor_initializers_thisInvocation_unnamed() async {
-    var library = await checkLibrary('''
-class C {
-  const C.named() : this(1, 'bbb');
-  const C(int a, String b);
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          const named @20
-            periodOffset: 19
-            nameEnd: 25
-            constantInitializers
-              RedirectingConstructorInvocation
-                argumentList: ArgumentList
-                  arguments
-                    IntegerLiteral
-                      literal: 1 @35
-                      staticType: int
-                    SimpleStringLiteral
-                      literal: 'bbb' @38
-                  leftParenthesis: ( @34
-                  rightParenthesis: ) @43
-                staticElement: self::@class::C::@constructor::•
-                thisKeyword: this @30
-            redirectedConstructor: self::@class::C::@constructor::•
-          const @54
-            parameters
-              requiredPositional a @60
-                type: int
-              requiredPositional b @70
-                type: String
-''');
-  }
-
-  test_constructor_redirected_factory_named() async {
-    var library = await checkLibrary('''
-class C {
-  factory C() = D.named;
-  C._();
-}
-class D extends C {
-  D.named() : super._();
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          factory @20
-            redirectedConstructor: self::@class::D::@constructor::named
-          _ @39
-            periodOffset: 38
-            nameEnd: 40
-      class D @52
-        supertype: C
-        constructors
-          named @70
-            periodOffset: 69
-            nameEnd: 75
-''');
-  }
-
-  test_constructor_redirected_factory_named_generic() async {
-    var library = await checkLibrary('''
-class C<T, U> {
-  factory C() = D<U, T>.named;
-  C._();
-}
-class D<T, U> extends C<U, T> {
-  D.named() : super._();
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        typeParameters
-          covariant T @8
-            defaultType: dynamic
-          covariant U @11
-            defaultType: dynamic
-        constructors
-          factory @26
-            redirectedConstructor: ConstructorMember
-              base: self::@class::D::@constructor::named
-              substitution: {T: U, U: T}
-          _ @51
-            periodOffset: 50
-            nameEnd: 52
-      class D @64
-        typeParameters
-          covariant T @66
-            defaultType: dynamic
-          covariant U @69
-            defaultType: dynamic
-        supertype: C<U, T>
-        constructors
-          named @94
-            periodOffset: 93
-            nameEnd: 99
-''');
-  }
-
-  test_constructor_redirected_factory_named_generic_viaTypeAlias() async {
-    var library = await checkLibrary('''
-typedef A<T, U> = C<T, U>;
-class B<T, U> {
-  factory B() = A<U, T>.named;
-  B._();
-}
-class C<T, U> extends A<U, T> {
-  C.named() : super._();
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class B @33
-        typeParameters
-          covariant T @35
-            defaultType: dynamic
-          covariant U @38
-            defaultType: dynamic
-        constructors
-          factory @53
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-      class C @91
-        typeParameters
-          covariant T @93
-            defaultType: dynamic
-          covariant U @96
-            defaultType: dynamic
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-          aliasElement: self::@typeAlias::A
-          aliasArguments
-            U
-            T
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-          named @121
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-      A @8
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-          covariant T @10
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-          covariant U @13
-            defaultType: dynamic
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-
-  test_constructor_redirected_factory_named_imported() async {
-    addLibrarySource('/foo.dart', '''
-import 'test.dart';
-class D extends C {
-  D.named() : super._();
-}
-''');
-    var library = await checkLibrary('''
-import 'foo.dart';
-class C {
-  factory C() = D.named;
-  C._();
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-    checkElementText(library, r'''
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-  }
-
-  test_constructor_redirected_factory_named_imported_generic() async {
-    addLibrarySource('/foo.dart', '''
-import 'test.dart';
-class D<T, U> extends C<U, T> {
-  D.named() : super._();
-}
-''');
-    var library = await checkLibrary('''
-import 'foo.dart';
-class C<T, U> {
-  factory C() = D<U, T>.named;
-  C._();
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-    checkElementText(library, r'''
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-
-  test_constructor_redirected_factory_named_prefixed() async {
-    addLibrarySource('/foo.dart', '''
-import 'test.dart';
-class D extends C {
-  D.named() : super._();
-}
-''');
-    var library = await checkLibrary('''
-import 'foo.dart' as foo;
-class C {
-  factory C() = foo.D.named;
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-    checkElementText(library, r'''
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-
-  test_constructor_redirected_factory_named_prefixed_generic() async {
-    addLibrarySource('/foo.dart', '''
-import 'test.dart';
-class D<T, U> extends C<U, T> {
-  D.named() : super._();
-}
-''');
-    var library = await checkLibrary('''
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-class C<T, U> {
-  factory C() = foo.D<U, T>.named;
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-
-  test_constructor_redirected_factory_named_unresolved_class() async {
-    var library = await checkLibrary('''
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-    checkElementText(library, r'''
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-
-  test_constructor_redirected_factory_named_unresolved_constructor() async {
-    var library = await checkLibrary('''
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-  factory C() = D.named<E>;
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-    checkElementText(library, r'''
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-
-  test_constructor_redirected_factory_unnamed() async {
-    var library = await checkLibrary('''
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-      class D @46
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-
-  test_constructor_redirected_factory_unnamed_generic() async {
-    var library = await checkLibrary('''
-class C<T, U> {
-  factory C() = D<U, T>;
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-    checkElementText(library, r'''
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-
-  test_constructor_redirected_factory_unnamed_generic_viaTypeAlias() async {
-    var library = await checkLibrary('''
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-
-  test_constructor_redirected_factory_unnamed_imported() async {
-    addLibrarySource('/foo.dart', '''
-import 'test.dart';
-class D extends C {
-  D() : super._();
-}
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-    var library = await checkLibrary('''
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-
-  test_constructor_redirected_factory_unnamed_imported_generic() async {
-    addLibrarySource('/foo.dart', '''
-import 'test.dart';
-class D<T, U> extends C<U, T> {
-  D() : super._();
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-''');
-    var library = await checkLibrary('''
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-          _ @64
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-
-  test_constructor_redirected_factory_unnamed_imported_viaTypeAlias() async {
-    addLibrarySource('/foo.dart', '''
-import 'test.dart';
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-class B extends C {
-  B() : super._();
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-    var library = await checkLibrary('''
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-
-  test_constructor_redirected_factory_unnamed_prefixed() async {
-    addLibrarySource('/foo.dart', '''
-import 'test.dart';
-class D extends C {
-  D() : super._();
-}
-''');
-    var library = await checkLibrary('''
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-  test_constructor_redirected_factory_unnamed_prefixed_generic() async {
-    addLibrarySource('/foo.dart', '''
-import 'test.dart';
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-  D() : super._();
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-    var library = await checkLibrary('''
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-
-  test_constructor_redirected_factory_unnamed_prefixed_viaTypeAlias() async {
-    addLibrarySource('/foo.dart', '''
-import 'test.dart';
-typedef A = B;
-class B extends C {
-  B() : super._();
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-
-  test_constructor_redirected_factory_unnamed_unresolved() async {
-    var library = await checkLibrary('''
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-  test_constructor_redirected_factory_unnamed_viaTypeAlias() async {
-    var library = await checkLibrary('''
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-  test_constructor_redirected_thisInvocation_named_notConst() async {
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-  test_constructor_redirected_thisInvocation_unnamed_notConst() async {
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-    var library = await checkLibrary('''
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-  test_constructor_withCycles_nonConst() async {
-    var library = await checkLibrary('''
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-
   test_defaultValue_eliminateTypeParameters() async {
     var library = await checkLibrary('''
 class A<T> {
@@ -14813,6 +16560,7 @@
                   rightParenthesis: ) @0
                 staticElement: self::@class::A::@constructor::•
                 superKeyword: super @0
+            superConstructor: self::@class::A::@constructor::•
       class alias X @48
         supertype: B
         mixins
@@ -14826,6 +16574,7 @@
                   rightParenthesis: ) @0
                 staticElement: self::@class::B::@constructor::•
                 superKeyword: super @0
+            superConstructor: self::@class::B::@constructor::•
     mixins
       mixin M @68
         superclassConstraints
@@ -14845,8 +16594,7 @@
   definingUnit
     enums
       enum E @5
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -14869,8 +16617,7 @@
           synthetic toString @-1
             returnType: String
       enum E @19
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -15127,8 +16874,7 @@
     enums
       enum E @65
         documentationComment: /**\n * Docs\n */
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -15164,8 +16910,7 @@
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     enums
       enum E @5
-        interfaces
-          Enum
+        supertype: Enum
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           synthetic final index @-1
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@@ -15212,8 +16957,7 @@
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     enums
       enum E @5
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -15273,8 +17017,7 @@
   definingUnit
     enums
       enum E @5
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -15306,8 +17049,7 @@
   definingUnit
     enums
       enum E1 @5
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -15326,8 +17068,7 @@
           synthetic toString @-1
             returnType: String
       enum E2 @20
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -15413,8 +17154,7 @@
                 superKeyword: super @0
     enums
       enum E @5
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -15813,6 +17553,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: foo.dart::@class::A::@constructor::•
 ''');
     var typeA = library.definingCompilationUnit.getType('B')!.supertype!;
     expect(typeA.element.source.shortName, 'foo.dart');
@@ -15845,6 +17586,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: foo_io.dart::@class::A::@constructor::•
 ''');
     var typeA = library.definingCompilationUnit.getType('B')!.supertype!;
     expect(typeA.element.source.shortName, 'foo_io.dart');
@@ -15877,6 +17619,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: foo_html.dart::@class::A::@constructor::•
 ''');
     var typeA = library.definingCompilationUnit.getType('B')!.supertype!;
     expect(typeA.element.source.shortName, 'foo_html.dart');
@@ -15964,745 +17707,6 @@
 ''');
   }
 
-  test_field_abstract() async {
-    var library = await checkLibrary('''
-abstract class C {
-  abstract int i;
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      abstract class C @15
-        fields
-          abstract i @34
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic abstract get i @-1
-            returnType: int
-          synthetic abstract set i @-1
-            parameters
-              requiredPositional _i @-1
-                type: int
-            returnType: void
-''');
-  }
-
-  test_field_covariant() async {
-    var library = await checkLibrary('''
-class C {
-  covariant int x;
-}''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          covariant x @26
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get x @-1
-            returnType: int
-          synthetic set x @-1
-            parameters
-              requiredPositional covariant _x @-1
-                type: int
-            returnType: void
-''');
-  }
-
-  test_field_documented() async {
-    var library = await checkLibrary('''
-class C {
-  /**
-   * Docs
-   */
-  var x;
-}''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          x @38
-            documentationComment: /**\n   * Docs\n   */
-            type: dynamic
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get x @-1
-            returnType: dynamic
-          synthetic set x @-1
-            parameters
-              requiredPositional _x @-1
-                type: dynamic
-            returnType: void
-''');
-  }
-
-  test_field_external() async {
-    var library = await checkLibrary('''
-abstract class C {
-  external int i;
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      abstract class C @15
-        fields
-          external i @34
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get i @-1
-            returnType: int
-          synthetic set i @-1
-            parameters
-              requiredPositional _i @-1
-                type: int
-            returnType: void
-''');
-  }
-
-  test_field_final_hasInitializer_hasConstConstructor() async {
-    var library = await checkLibrary('''
-class C {
-  final x = 42;
-  const C();
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          final x @18
-            type: int
-            constantInitializer
-              IntegerLiteral
-                literal: 42 @22
-                staticType: int
-        constructors
-          const @34
-        accessors
-          synthetic get x @-1
-            returnType: int
-''');
-  }
-
-  test_field_final_hasInitializer_hasConstConstructor_genericFunctionType() async {
-    var library = await checkLibrary('''
-class A<T> {
-  const A();
-}
-class B {
-  final f = const A<int Function(double a)>();
-  const B();
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class A @6
-        typeParameters
-          covariant T @8
-            defaultType: dynamic
-        constructors
-          const @21
-      class B @34
-        fields
-          final f @46
-            type: A<int Function(double)>
-            constantInitializer
-              InstanceCreationExpression
-                argumentList: ArgumentList
-                  leftParenthesis: ( @81
-                  rightParenthesis: ) @82
-                constructorName: ConstructorName
-                  staticElement: ConstructorMember
-                    base: self::@class::A::@constructor::•
-                    substitution: {T: int Function(double)}
-                  type: NamedType
-                    name: SimpleIdentifier
-                      staticElement: self::@class::A
-                      staticType: null
-                      token: A @56
-                    type: A<int Function(double)>
-                    typeArguments: TypeArgumentList
-                      arguments
-                        GenericFunctionType
-                          declaredElement: GenericFunctionTypeElement
-                            parameters
-                              a
-                                kind: required positional
-                                type: double
-                            returnType: int
-                            type: int Function(double)
-                          functionKeyword: Function @62
-                          parameters: FormalParameterList
-                            leftParenthesis: ( @70
-                            parameters
-                              SimpleFormalParameter
-                                declaredElement: a@78
-                                declaredElementType: double
-                                identifier: SimpleIdentifier
-                                  staticElement: a@78
-                                  staticType: null
-                                  token: a @78
-                                type: NamedType
-                                  name: SimpleIdentifier
-                                    staticElement: dart:core::@class::double
-                                    staticType: null
-                                    token: double @71
-                                  type: double
-                            rightParenthesis: ) @79
-                          returnType: NamedType
-                            name: SimpleIdentifier
-                              staticElement: dart:core::@class::int
-                              staticType: null
-                              token: int @58
-                            type: int
-                          type: int Function(double)
-                      leftBracket: < @57
-                      rightBracket: > @80
-                keyword: const @50
-                staticType: A<int Function(double)>
-        constructors
-          const @93
-        accessors
-          synthetic get f @-1
-            returnType: A<int Function(double)>
-''');
-  }
-
-  test_field_final_hasInitializer_noConstConstructor() async {
-    var library = await checkLibrary('''
-class C {
-  final x = 42;
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          final x @18
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get x @-1
-            returnType: int
-''');
-  }
-
-  test_field_formal_param_inferred_type_implicit() async {
-    var library = await checkLibrary('class C extends D { var v; C(this.v); }'
-        ' abstract class D { int get v; }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        supertype: D
-        fields
-          v @24
-            type: int
-        constructors
-          @27
-            parameters
-              requiredPositional final this.v @34
-                type: int
-        accessors
-          synthetic get v @-1
-            returnType: int
-          synthetic set v @-1
-            parameters
-              requiredPositional _v @-1
-                type: int
-            returnType: void
-      abstract class D @55
-        fields
-          synthetic v @-1
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          abstract get v @67
-            returnType: int
-''');
-  }
-
-  test_field_inferred_type_nonStatic_explicit_initialized() async {
-    var library = await checkLibrary('class C { num v = 0; }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          v @14
-            type: num
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get v @-1
-            returnType: num
-          synthetic set v @-1
-            parameters
-              requiredPositional _v @-1
-                type: num
-            returnType: void
-''');
-  }
-
-  test_field_inferred_type_nonStatic_implicit_initialized() async {
-    var library = await checkLibrary('class C { var v = 0; }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          v @14
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get v @-1
-            returnType: int
-          synthetic set v @-1
-            parameters
-              requiredPositional _v @-1
-                type: int
-            returnType: void
-''');
-  }
-
-  test_field_inferred_type_nonStatic_implicit_uninitialized() async {
-    var library = await checkLibrary(
-        'class C extends D { var v; } abstract class D { int get v; }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        supertype: D
-        fields
-          v @24
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get v @-1
-            returnType: int
-          synthetic set v @-1
-            parameters
-              requiredPositional _v @-1
-                type: int
-            returnType: void
-      abstract class D @44
-        fields
-          synthetic v @-1
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          abstract get v @56
-            returnType: int
-''');
-  }
-
-  test_field_inferred_type_nonStatic_inherited_resolveInitializer() async {
-    var library = await checkLibrary(r'''
-const a = 0;
-abstract class A {
-  const A();
-  List<int> get f;
-}
-class B extends A {
-  const B();
-  final f = [a];
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      abstract class A @28
-        fields
-          synthetic f @-1
-            type: List<int>
-        constructors
-          const @40
-        accessors
-          abstract get f @61
-            returnType: List<int>
-      class B @72
-        supertype: A
-        fields
-          final f @107
-            type: List<int>
-            constantInitializer
-              ListLiteral
-                elements
-                  SimpleIdentifier
-                    staticElement: self::@getter::a
-                    staticType: int
-                    token: a @112
-                leftBracket: [ @111
-                rightBracket: ] @113
-                staticType: List<int>
-        constructors
-          const @94
-        accessors
-          synthetic get f @-1
-            returnType: List<int>
-    topLevelVariables
-      static const a @6
-        type: int
-        constantInitializer
-          IntegerLiteral
-            literal: 0 @10
-            staticType: int
-    accessors
-      synthetic static get a @-1
-        returnType: int
-''');
-  }
-
-  test_field_inferred_type_static_implicit_initialized() async {
-    var library = await checkLibrary('class C { static var v = 0; }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          static v @21
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic static get v @-1
-            returnType: int
-          synthetic static set v @-1
-            parameters
-              requiredPositional _v @-1
-                type: int
-            returnType: void
-''');
-  }
-
-  test_field_propagatedType_const_noDep() async {
-    var library = await checkLibrary('''
-class C {
-  static const x = 0;
-}''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          static const x @25
-            type: int
-            constantInitializer
-              IntegerLiteral
-                literal: 0 @29
-                staticType: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic static get x @-1
-            returnType: int
-''');
-  }
-
-  test_field_propagatedType_final_dep_inLib() async {
-    addLibrarySource('/a.dart', 'final a = 1;');
-    var library = await checkLibrary('''
-import "a.dart";
-class C {
-  final b = a / 2;
-}''');
-    checkElementText(library, r'''
-library
-  imports
-    a.dart
-  definingUnit
-    classes
-      class C @23
-        fields
-          final b @35
-            type: double
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get b @-1
-            returnType: double
-''');
-  }
-
-  test_field_propagatedType_final_dep_inPart() async {
-    addSource('/a.dart', 'part of lib; final a = 1;');
-    var library = await checkLibrary('''
-library lib;
-part "a.dart";
-class C {
-  final b = a / 2;
-}''');
-    checkElementText(library, r'''
-library
-  name: lib
-  nameOffset: 8
-  definingUnit
-    classes
-      class C @34
-        fields
-          final b @46
-            type: double
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get b @-1
-            returnType: double
-  parts
-    a.dart
-      topLevelVariables
-        static final a @19
-          type: int
-      accessors
-        synthetic static get a @-1
-          returnType: int
-''');
-  }
-
-  test_field_propagatedType_final_noDep_instance() async {
-    var library = await checkLibrary('''
-class C {
-  final x = 0;
-}''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          final x @18
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get x @-1
-            returnType: int
-''');
-  }
-
-  test_field_propagatedType_final_noDep_static() async {
-    var library = await checkLibrary('''
-class C {
-  static final x = 0;
-}''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          static final x @25
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic static get x @-1
-            returnType: int
-''');
-  }
-
-  test_field_static_final_untyped() async {
-    var library = await checkLibrary('class C { static final x = 0; }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          static final x @23
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic static get x @-1
-            returnType: int
-''');
-  }
-
-  test_field_type_inferred_Never() async {
-    var library = await checkLibrary(r'''
-class C {
-  var a = throw 42;
-}
-''');
-
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          a @16
-            type: Never
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get a @-1
-            returnType: Never
-          synthetic set a @-1
-            parameters
-              requiredPositional _a @-1
-                type: Never
-            returnType: void
-''');
-  }
-
-  test_field_type_inferred_nonNullify() async {
-    addSource('/a.dart', '''
-// @dart = 2.7
-var a = 0;
-''');
-
-    var library = await checkLibrary(r'''
-import 'a.dart';
-class C {
-  var b = a;
-}
-''');
-
-    checkElementText(library, r'''
-library
-  imports
-    a.dart
-  definingUnit
-    classes
-      class C @23
-        fields
-          b @33
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get b @-1
-            returnType: int
-          synthetic set b @-1
-            parameters
-              requiredPositional _b @-1
-                type: int
-            returnType: void
-''');
-  }
-
-  test_field_typed() async {
-    var library = await checkLibrary('class C { int x = 0; }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          x @14
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get x @-1
-            returnType: int
-          synthetic set x @-1
-            parameters
-              requiredPositional _x @-1
-                type: int
-            returnType: void
-''');
-  }
-
-  test_field_untyped() async {
-    var library = await checkLibrary('class C { var x = 0; }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          x @14
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get x @-1
-            returnType: int
-          synthetic set x @-1
-            parameters
-              requiredPositional _x @-1
-                type: int
-            returnType: void
-''');
-  }
-
-  test_finalField_hasConstConstructor() async {
-    var library = await checkLibrary(r'''
-class C1  {
-  final List<int> f1 = const [];
-  const C1();
-}
-class C2  {
-  final List<int> f2 = const [];
-  C2();
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C1 @6
-        fields
-          final f1 @30
-            type: List<int>
-            constantInitializer
-              ListLiteral
-                constKeyword: const @35
-                leftBracket: [ @41
-                rightBracket: ] @42
-                staticType: List<int>
-        constructors
-          const @53
-        accessors
-          synthetic get f1 @-1
-            returnType: List<int>
-      class C2 @67
-        fields
-          final f2 @91
-            type: List<int>
-        constructors
-          @108
-        accessors
-          synthetic get f2 @-1
-            returnType: List<int>
-''');
-  }
-
   test_function_async() async {
     var library = await checkLibrary(r'''
 import 'dart:async';
@@ -18268,6 +19272,9 @@
                   rightParenthesis: ) @0
                 staticElement: self::@class::A::@constructor::•
                 superKeyword: super @0
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {T: void Function()}
     mixins
       mixin M @20
         superclassConstraints
@@ -18438,6 +19445,7 @@
             type: int
         constructors
           synthetic @-1
+            superConstructor: self::@class::D::@constructor::•
         accessors
           get f @24
             returnType: int
@@ -18609,6 +19617,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: foo.dart::@class::A::@constructor::•
 ''');
     var typeA = library.definingCompilationUnit.getType('B')!.supertype!;
     expect(typeA.element.source.shortName, 'foo.dart');
@@ -18639,6 +19648,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: foo_io.dart::@class::A::@constructor::•
 ''');
     var typeA = library.definingCompilationUnit.getType('B')!.supertype!;
     expect(typeA.element.source.shortName, 'foo_io.dart');
@@ -18669,6 +19679,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: foo_io.dart::@class::A::@constructor::•
 ''');
     var typeA = library.definingCompilationUnit.getType('B')!.supertype!;
     expect(typeA.element.source.shortName, 'foo_io.dart');
@@ -18699,6 +19710,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: foo_html.dart::@class::A::@constructor::•
 ''');
     var typeA = library.definingCompilationUnit.getType('B')!.supertype!;
     expect(typeA.element.source.shortName, 'foo_html.dart');
@@ -18729,6 +19741,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: foo_html.dart::@class::A::@constructor::•
 ''');
     var typeA = library.definingCompilationUnit.getType('B')!.supertype!;
     expect(typeA.element.source.shortName, 'foo_html.dart');
@@ -18929,6 +19942,7 @@
         supertype: C
         constructors
           synthetic @-1
+            superConstructor: self::@class::C::@constructor::•
 ''');
   }
 
@@ -19216,6 +20230,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
       class S @40
         typeParameters
           covariant T @42
@@ -19293,6 +20308,7 @@
         supertype: C
         constructors
           synthetic @-1
+            superConstructor: self::@class::C::@constructor::•
     topLevelVariables
       static a @111
         type: A
@@ -19690,6 +20706,7 @@
               aliasElement: self::@typeAlias::F
         constructors
           synthetic @-1
+            superConstructor: self::@class::D::@constructor::•
         accessors
           synthetic get v @-1
             returnType: int Function(String)
@@ -19845,6 +20862,9 @@
             type: Map<T, int>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::D::@constructor::•
+              substitution: {U: int, V: T}
         accessors
           synthetic get v @-1
             returnType: Map<T, int>
@@ -19932,6 +20952,9 @@
         supertype: D<U, int>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::D::@constructor::•
+              substitution: {V: U, W: int}
         methods
           f @41
             parameters
@@ -19988,6 +21011,7 @@
         supertype: D
         constructors
           synthetic @-1
+            superConstructor: a.dart::@class::D::@constructor::•
         methods
           f @44
             parameters
@@ -20010,6 +21034,7 @@
         supertype: D
         constructors
           synthetic @-1
+            superConstructor: self::@class::D::@constructor::•
         methods
           f @25
             parameters
@@ -20115,6 +21140,7 @@
             type: int Function(String)
         constructors
           synthetic @-1
+            superConstructor: self::@class::D::@constructor::•
         accessors
           set f @29
             parameters
@@ -20162,6 +21188,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: a.dart::@class::A::@constructor::•
         methods
           m @39
             parameters
@@ -20349,6 +21376,7 @@
             type: dynamic
         constructors
           synthetic @-1
+            superConstructor: self::@class::C::@constructor::•
         accessors
           synthetic get f @-1
             returnType: dynamic
@@ -20550,6 +21578,7 @@
         supertype: LegacyDefault*
         constructors
           synthetic @-1
+            superConstructor: legacy.dart::@class::LegacyDefault::@constructor::•
         methods
           == @71
             parameters
@@ -20560,6 +21589,7 @@
         supertype: LegacyObject*
         constructors
           synthetic @-1
+            superConstructor: legacy.dart::@class::LegacyObject::@constructor::•
         methods
           == @140
             parameters
@@ -20570,6 +21600,7 @@
         supertype: LegacyInt*
         constructors
           synthetic @-1
+            superConstructor: legacy.dart::@class::LegacyInt::@constructor::•
         methods
           == @206
             parameters
@@ -20630,6 +21661,7 @@
           NullSafeDefault*
         constructors
           synthetic @-1
+            superConstructor: legacy.dart::@class::LegacyDefault::@constructor::•
         methods
           == @136
             parameters
@@ -20642,6 +21674,7 @@
           NullSafeObject*
         constructors
           synthetic @-1
+            superConstructor: legacy.dart::@class::LegacyObject::@constructor::•
         methods
           == @231
             parameters
@@ -20654,6 +21687,7 @@
           NullSafeInt*
         constructors
           synthetic @-1
+            superConstructor: legacy.dart::@class::LegacyInt::@constructor::•
         methods
           == @320
             parameters
@@ -20697,6 +21731,7 @@
         supertype: NullSafeDefault
         constructors
           synthetic @-1
+            superConstructor: nullSafe.dart::@class::NullSafeDefault::@constructor::•
         methods
           == @74
             parameters
@@ -20707,6 +21742,7 @@
         supertype: NullSafeObject
         constructors
           synthetic @-1
+            superConstructor: nullSafe.dart::@class::NullSafeObject::@constructor::•
         methods
           == @145
             parameters
@@ -20717,6 +21753,7 @@
         supertype: NullSafeInt
         constructors
           synthetic @-1
+            superConstructor: nullSafe.dart::@class::NullSafeInt::@constructor::•
         methods
           == @213
             parameters
@@ -21669,6 +22706,7 @@
                   rightParenthesis: ) @0
                 staticElement: self::@class::C::@constructor::•
                 superKeyword: super @0
+            superConstructor: self::@class::C::@constructor::•
       class C @29
         constructors
           synthetic @-1
@@ -21779,71 +22817,6 @@
 ''');
   }
 
-  test_member_function_async() async {
-    var library = await checkLibrary(r'''
-import 'dart:async';
-class C {
-  Future f() async {}
-}
-''');
-    checkElementText(library, r'''
-library
-  imports
-    dart:async
-  definingUnit
-    classes
-      class C @27
-        constructors
-          synthetic @-1
-        methods
-          f @40 async
-            returnType: Future<dynamic>
-''');
-  }
-
-  test_member_function_asyncStar() async {
-    var library = await checkLibrary(r'''
-import 'dart:async';
-class C {
-  Stream f() async* {}
-}
-''');
-    checkElementText(library, r'''
-library
-  imports
-    dart:async
-  definingUnit
-    classes
-      class C @27
-        constructors
-          synthetic @-1
-        methods
-          f @40 async*
-            returnType: Stream<dynamic>
-''');
-  }
-
-  test_member_function_syncStar() async {
-    var library = await checkLibrary(r'''
-class C {
-  Iterable<int> f() sync* {
-    yield 42;
-  }
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          synthetic @-1
-        methods
-          f @26 sync*
-            returnType: Iterable<int>
-''');
-  }
-
   test_metadata_class_field_first() async {
     var library = await checkLibrary(r'''
 const a = 0;
@@ -22045,6 +23018,7 @@
                   rightParenthesis: ) @0
                 staticElement: self::@class::D::@constructor::•
                 superKeyword: super @0
+            superConstructor: self::@class::D::@constructor::•
       class D @45
         constructors
           synthetic @-1
@@ -22495,6 +23469,7 @@
                 period: . @0
                 staticElement: self::@class::A::@constructor::named
                 superKeyword: super @0
+            superConstructor: self::@class::A::@constructor::named
       class D @85
         metadata
           Annotation
@@ -22845,6 +23820,7 @@
                   rightParenthesis: ) @0
                 staticElement: self::@class::A::@constructor::•
                 superKeyword: super @0
+            superConstructor: self::@class::A::@constructor::•
       class D @73
         metadata
           Annotation
@@ -22974,8 +23950,7 @@
   definingUnit
     enums
       enum E @19
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -23045,8 +24020,7 @@
             returnType: dynamic
     enums
       enum E @64
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -23120,8 +24094,7 @@
               staticElement: self::@getter::a
               staticType: null
               token: a @15
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -24574,6 +25547,7 @@
                   rightParenthesis: ) @0
                 staticElement: self::@class::A::@constructor::•
                 superKeyword: super @0
+            superConstructor: self::@class::A::@constructor::•
     mixins
       mixin M @33
         superclassConstraints
@@ -24617,8 +25591,7 @@
               staticElement: self::@getter::foo
               staticType: null
               token: foo @17
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -25499,6 +26472,58 @@
 ''');
   }
 
+  test_metadata_superFormalParameter() async {
+    var library = await checkLibrary('''
+const a = null;
+
+class A {
+  A(int x);
+}
+
+class B extends A {
+  B(@a super.x);
+}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class A @23
+        constructors
+          @29
+            parameters
+              requiredPositional x @35
+                type: int
+      class B @48
+        supertype: A
+        constructors
+          @64
+            parameters
+              requiredPositional final super.x @75
+                type: int
+                metadata
+                  Annotation
+                    atSign: @ @66
+                    element: self::@getter::a
+                    name: SimpleIdentifier
+                      staticElement: self::@getter::a
+                      staticType: null
+                      token: a @67
+                superConstructorParameter: x@35
+            superConstructor: self::@class::A::@constructor::•
+    topLevelVariables
+      static const a @6
+        type: dynamic
+        constantInitializer
+          NullLiteral
+            literal: null @10
+            staticType: Null
+    accessors
+      synthetic static get a @-1
+        returnType: dynamic
+''');
+  }
+
   test_metadata_topLevelVariableDeclaration() async {
     var library = await checkLibrary('const a = null; @a int v;');
     checkElementText(library, r'''
@@ -25601,6 +26626,7 @@
                   rightParenthesis: ) @0
                 staticElement: self::@class::D::@constructor::•
                 superKeyword: super @0
+            superConstructor: self::@class::D::@constructor::•
       class D @48
         constructors
           synthetic @-1
@@ -25809,8 +26835,7 @@
           synthetic @-1
     enums
       enum E @5
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -25931,187 +26956,6 @@
 ''');
   }
 
-  test_method_documented() async {
-    var library = await checkLibrary('''
-class C {
-  /**
-   * Docs
-   */
-  f() {}
-}''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          synthetic @-1
-        methods
-          f @34
-            documentationComment: /**\n   * Docs\n   */
-            returnType: dynamic
-''');
-  }
-
-  test_method_hasImplicitReturnType_false() async {
-    var library = await checkLibrary('''
-class C {
-  int m() => 0;
-}
-''');
-    var c = library.definingCompilationUnit.classes.single;
-    var m = c.methods.single;
-    expect(m.hasImplicitReturnType, isFalse);
-  }
-
-  test_method_hasImplicitReturnType_true() async {
-    var library = await checkLibrary('''
-class C {
-  m() => 0;
-}
-''');
-    var c = library.definingCompilationUnit.classes.single;
-    var m = c.methods.single;
-    expect(m.hasImplicitReturnType, isTrue);
-  }
-
-  test_method_inferred_type_nonStatic_implicit_param() async {
-    var library = await checkLibrary('class C extends D { void f(value) {} }'
-        ' abstract class D { void f(int value); }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        supertype: D
-        constructors
-          synthetic @-1
-        methods
-          f @25
-            parameters
-              requiredPositional value @27
-                type: int
-            returnType: void
-      abstract class D @54
-        constructors
-          synthetic @-1
-        methods
-          abstract f @63
-            parameters
-              requiredPositional value @69
-                type: int
-            returnType: void
-''');
-  }
-
-  test_method_inferred_type_nonStatic_implicit_return() async {
-    var library = await checkLibrary('''
-class C extends D {
-  f() => null;
-}
-abstract class D {
-  int f();
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        supertype: D
-        constructors
-          synthetic @-1
-        methods
-          f @22
-            returnType: int
-      abstract class D @52
-        constructors
-          synthetic @-1
-        methods
-          abstract f @62
-            returnType: int
-''');
-  }
-
-  test_method_type_parameter() async {
-    var library = await checkLibrary('class C { T f<T, U>(U u) => null; }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          synthetic @-1
-        methods
-          f @12
-            typeParameters
-              covariant T @14
-              covariant U @17
-            parameters
-              requiredPositional u @22
-                type: U
-            returnType: T
-''');
-  }
-
-  test_method_type_parameter_in_generic_class() async {
-    var library = await checkLibrary('''
-class C<T, U> {
-  V f<V, W>(T t, U u, W w) => null;
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        typeParameters
-          covariant T @8
-            defaultType: dynamic
-          covariant U @11
-            defaultType: dynamic
-        constructors
-          synthetic @-1
-        methods
-          f @20
-            typeParameters
-              covariant V @22
-              covariant W @25
-            parameters
-              requiredPositional t @30
-                type: T
-              requiredPositional u @35
-                type: U
-              requiredPositional w @40
-                type: W
-            returnType: V
-''');
-  }
-
-  test_method_type_parameter_with_function_typed_parameter() async {
-    var library = await checkLibrary('class C { void f<T, U>(T x(U u)) {} }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          synthetic @-1
-        methods
-          f @15
-            typeParameters
-              covariant T @17
-              covariant U @20
-            parameters
-              requiredPositional x @25
-                type: T Function(U)
-                parameters
-                  requiredPositional u @29
-                    type: U
-            returnType: void
-''');
-  }
-
   test_methodInvocation_implicitCall() async {
     var library = await checkLibrary(r'''
 class A {
@@ -26311,6 +27155,9 @@
           M<int*>*
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {T: int*}
     mixins
       mixin M @20
         typeParameters
@@ -26345,6 +27192,9 @@
           M<int>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {T: int}
     mixins
       mixin M @20
         typeParameters
@@ -26383,6 +27233,9 @@
           C<int*>*
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: a.dart::@class::A::@constructor::•
+              substitution: {T: int*}
 ''');
   }
 
@@ -26408,6 +27261,9 @@
           M<int*>*
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: a.dart::@class::A::@constructor::•
+              substitution: {T: int*}
 ''');
   }
 
@@ -26854,7 +27710,7 @@
     functions
       f @5
         parameters
-          requiredName f @22
+          requiredNamed f @22
             type: void Function<U>(int)
             typeParameters
               covariant U @24
@@ -27290,8 +28146,7 @@
   definingUnit
     enums
       enum E @5
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -27586,203 +28441,6 @@
         withNonSynthetic: true);
   }
 
-  test_old_typedef_notSimplyBounded_self() async {
-    var library = await checkLibrary('''
-typedef void F<T extends F>();
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased notSimplyBounded F @13
-        typeParameters
-          unrelated T @15
-            bound: dynamic
-            defaultType: dynamic
-        aliasedType: void Function()
-        aliasedElement: GenericFunctionTypeElement
-          returnType: void
-''');
-  }
-
-  test_old_typedef_notSimplyBounded_simple_because_non_generic() async {
-    var library = await checkLibrary('''
-typedef void F();
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased F @13
-        aliasedType: void Function()
-        aliasedElement: GenericFunctionTypeElement
-          returnType: void
-''');
-  }
-
-  test_old_typedef_notSimplyBounded_simple_no_bounds() async {
-    var library = await checkLibrary('typedef void F<T>();');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased F @13
-        typeParameters
-          unrelated T @15
-            defaultType: dynamic
-        aliasedType: void Function()
-        aliasedElement: GenericFunctionTypeElement
-          returnType: void
-''');
-  }
-
-  test_operator() async {
-    var library =
-        await checkLibrary('class C { C operator+(C other) => null; }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          synthetic @-1
-        methods
-          + @20
-            parameters
-              requiredPositional other @24
-                type: C
-            returnType: C
-''');
-  }
-
-  test_operator_equal() async {
-    var library = await checkLibrary('''
-class C {
-  bool operator==(Object other) => false;
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          synthetic @-1
-        methods
-          == @25
-            parameters
-              requiredPositional other @35
-                type: Object
-            returnType: bool
-''');
-  }
-
-  test_operator_external() async {
-    var library =
-        await checkLibrary('class C { external C operator+(C other); }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          synthetic @-1
-        methods
-          external + @29
-            parameters
-              requiredPositional other @33
-                type: C
-            returnType: C
-''');
-  }
-
-  test_operator_greater_equal() async {
-    var library = await checkLibrary('''
-class C {
-  bool operator>=(C other) => false;
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          synthetic @-1
-        methods
-          >= @25
-            parameters
-              requiredPositional other @30
-                type: C
-            returnType: bool
-''');
-  }
-
-  test_operator_index() async {
-    var library =
-        await checkLibrary('class C { bool operator[](int i) => null; }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          synthetic @-1
-        methods
-          [] @23
-            parameters
-              requiredPositional i @30
-                type: int
-            returnType: bool
-''');
-  }
-
-  test_operator_index_set() async {
-    var library = await checkLibrary('''
-class C {
-  void operator[]=(int i, bool v) {}
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          synthetic @-1
-        methods
-          []= @25
-            parameters
-              requiredPositional i @33
-                type: int
-              requiredPositional v @41
-                type: bool
-            returnType: void
-''');
-  }
-
-  test_operator_less_equal() async {
-    var library = await checkLibrary('''
-class C {
-  bool operator<=(C other) => false;
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        constructors
-          synthetic @-1
-        methods
-          <= @25
-            parameters
-              requiredPositional other @30
-                type: C
-            returnType: bool
-''');
-  }
-
   test_parameter() async {
     var library = await checkLibrary('void main(int p) {}');
     checkElementText(library, r'''
@@ -27895,6 +28553,9 @@
         supertype: A<T>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {T: T}
         methods
           f @75
             parameters
@@ -27930,6 +28591,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           m @68
             parameters
@@ -28292,28 +28954,6 @@
 ''');
   }
 
-  test_setter_covariant() async {
-    var library =
-        await checkLibrary('class C { void set x(covariant int value); }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          synthetic x @-1
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          abstract set x @19
-            parameters
-              requiredPositional covariant value @35
-                type: int
-            returnType: void
-''');
-  }
-
   test_setter_documented() async {
     var library = await checkLibrary('''
 // Extra comment so doc comment offset != 0
@@ -28354,136 +28994,6 @@
 ''');
   }
 
-  test_setter_inferred_type_conflictingInheritance() async {
-    var library = await checkLibrary('''
-class A {
-  int t;
-}
-class B extends A {
-  double t;
-}
-class C extends A implements B {
-}
-class D extends C {
-  void set t(p) {}
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class A @6
-        fields
-          t @16
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get t @-1
-            returnType: int
-          synthetic set t @-1
-            parameters
-              requiredPositional _t @-1
-                type: int
-            returnType: void
-      class B @27
-        supertype: A
-        fields
-          t @50
-            type: double
-        constructors
-          synthetic @-1
-        accessors
-          synthetic get t @-1
-            returnType: double
-          synthetic set t @-1
-            parameters
-              requiredPositional _t @-1
-                type: double
-            returnType: void
-      class C @61
-        supertype: A
-        interfaces
-          B
-        constructors
-          synthetic @-1
-      class D @96
-        supertype: C
-        fields
-          synthetic t @-1
-            type: dynamic
-        constructors
-          synthetic @-1
-        accessors
-          set t @121
-            parameters
-              requiredPositional p @123
-                type: dynamic
-            returnType: void
-''');
-  }
-
-  test_setter_inferred_type_nonStatic_implicit_param() async {
-    var library =
-        await checkLibrary('class C extends D { void set f(value) {} }'
-            ' abstract class D { void set f(int value); }');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        supertype: D
-        fields
-          synthetic f @-1
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          set f @29
-            parameters
-              requiredPositional value @31
-                type: int
-            returnType: void
-      abstract class D @58
-        fields
-          synthetic f @-1
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          abstract set f @71
-            parameters
-              requiredPositional value @77
-                type: int
-            returnType: void
-''');
-  }
-
-  test_setter_inferred_type_static_implicit_return() async {
-    var library = await checkLibrary('''
-class C {
-  static set f(int value) {}
-}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class C @6
-        fields
-          synthetic static f @-1
-            type: int
-        constructors
-          synthetic @-1
-        accessors
-          static set f @23
-            parameters
-              requiredPositional value @29
-                type: int
-            returnType: void
-''');
-  }
-
   test_setter_inferred_type_top_level_implicit_return() async {
     var library = await checkLibrary('set f(int value) {}');
     checkElementText(library, r'''
@@ -29043,6 +29553,9 @@
                   rightParenthesis: ) @0
                 staticElement: self::@class::A::@constructor::•
                 superKeyword: super @0
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {T: T}
       class C @78
         fields
           a @88
@@ -29259,6 +29772,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
       class C @40
         typeParameters
           covariant T @42
@@ -29601,8 +30115,7 @@
           synthetic @-1
     enums
       enum E @16
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -29709,8 +30222,7 @@
             synthetic @-1
       enums
         enum E @27
-          interfaces
-            Enum
+          supertype: Enum
           fields
             synthetic final index @-1
               type: int
@@ -29751,8 +30263,7 @@
           synthetic @-1
     enums
       enum E @42
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -29830,8 +30341,7 @@
             synthetic @-1
       enums
         enum E @27
-          interfaces
-            Enum
+          supertype: Enum
           fields
             synthetic final index @-1
               type: int
@@ -29907,8 +30417,7 @@
             synthetic @-1
       enums
         enum E @27
-          interfaces
-            Enum
+          supertype: Enum
           fields
             synthetic final index @-1
               type: int
@@ -30052,8 +30561,7 @@
   definingUnit
     enums
       enum E @5
-        interfaces
-          Enum
+        supertype: Enum
         fields
           synthetic final index @-1
             type: int
@@ -31012,26 +31520,7 @@
 ''');
   }
 
-  test_typedef_documented() async {
-    var library = await checkLibrary('''
-// Extra comment so doc comment offset != 0
-/**
- * Docs
- */
-typedef F();''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased F @68
-        documentationComment: /**\n * Docs\n */
-        aliasedType: dynamic Function()
-        aliasedElement: GenericFunctionTypeElement
-          returnType: dynamic
-''');
-  }
-
-  test_typedef_generic() async {
+  test_typedef_function_generic() async {
     var library = await checkLibrary(
         'typedef F<T> = int Function<S>(List<S> list, num Function<A>(A), T);');
     checkElementText(library, r'''
@@ -31057,7 +31546,7 @@
 ''');
   }
 
-  test_typedef_generic_asFieldType() async {
+  test_typedef_function_generic_asFieldType() async {
     var library = await checkLibrary(r'''
 typedef Foo<S> = S Function<T>(T x);
 class A {
@@ -31107,31 +31596,635 @@
 ''');
   }
 
-  test_typedef_generic_invalid() async {
+  test_typedef_function_notSimplyBounded_dependency_via_param_type_name_included() async {
+    // F is considered "not simply bounded" because it expands to a type that
+    // refers to C, which is not simply bounded.
     var library = await checkLibrary('''
-typedef F = int;
-F f;
+typedef F = void Function(C c);
+class C<T extends C<T>> {}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      notSimplyBounded class C @38
+        typeParameters
+          covariant T @40
+            bound: C<T>
+            defaultType: C<dynamic>
+        constructors
+          synthetic @-1
+    typeAliases
+      notSimplyBounded F @8
+        aliasedType: void Function(C<C<dynamic>>)
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional c @28
+              type: C<C<dynamic>>
+          returnType: void
+''');
+  }
+
+  test_typedef_function_notSimplyBounded_dependency_via_param_type_name_omitted() async {
+    // F is considered "not simply bounded" because it expands to a type that
+    // refers to C, which is not simply bounded.
+    var library = await checkLibrary('''
+typedef F = void Function(C);
+class C<T extends C<T>> {}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      notSimplyBounded class C @36
+        typeParameters
+          covariant T @38
+            bound: C<T>
+            defaultType: C<dynamic>
+        constructors
+          synthetic @-1
+    typeAliases
+      notSimplyBounded F @8
+        aliasedType: void Function(C<C<dynamic>>)
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional @-1
+              type: C<C<dynamic>>
+          returnType: void
+''');
+  }
+
+  test_typedef_function_notSimplyBounded_dependency_via_return_type() async {
+    // F is considered "not simply bounded" because it expands to a type that
+    // refers to C, which is not simply bounded.
+    var library = await checkLibrary('''
+typedef F = C Function();
+class C<T extends C<T>> {}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      notSimplyBounded class C @32
+        typeParameters
+          covariant T @34
+            bound: C<T>
+            defaultType: C<dynamic>
+        constructors
+          synthetic @-1
+    typeAliases
+      notSimplyBounded F @8
+        aliasedType: C<C<dynamic>> Function()
+        aliasedElement: GenericFunctionTypeElement
+          returnType: C<C<dynamic>>
+''');
+  }
+
+  test_typedef_function_typeParameters_f_bound_simple() async {
+    var library =
+        await checkLibrary('typedef F<T extends U, U> = U Function(T t);');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      notSimplyBounded F @8
+        typeParameters
+          contravariant T @10
+            bound: U
+            defaultType: Never
+          covariant U @23
+            defaultType: dynamic
+        aliasedType: U Function(T)
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional t @41
+              type: T
+          returnType: U
+''');
+  }
+
+  test_typedef_function_typeParameters_f_bound_simple_legacy() async {
+    featureSet = FeatureSets.language_2_9;
+    var library =
+        await checkLibrary('typedef F<T extends U, U> = U Function(T t);');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      notSimplyBounded F @8
+        typeParameters
+          contravariant T @10
+            bound: U*
+            defaultType: Null*
+          covariant U @23
+            defaultType: dynamic
+        aliasedType: U* Function(T*)*
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional t @41
+              type: T*
+          returnType: U*
+''');
+  }
+
+  test_typedef_legacy_documented() async {
+    var library = await checkLibrary('''
+// Extra comment so doc comment offset != 0
+/**
+ * Docs
+ */
+typedef F();''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased F @68
+        documentationComment: /**\n * Docs\n */
+        aliasedType: dynamic Function()
+        aliasedElement: GenericFunctionTypeElement
+          returnType: dynamic
+''');
+  }
+
+  test_typedef_legacy_notSimplyBounded_dependency_via_param_type() async {
+    // F is considered "not simply bounded" because it expands to a type that
+    // refers to C, which is not simply bounded.
+    var library = await checkLibrary('''
+typedef void F(C c);
+class C<T extends C<T>> {}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      notSimplyBounded class C @27
+        typeParameters
+          covariant T @29
+            bound: C<T>
+            defaultType: C<dynamic>
+        constructors
+          synthetic @-1
+    typeAliases
+      functionTypeAliasBased notSimplyBounded F @13
+        aliasedType: void Function(C<C<dynamic>>)
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional c @17
+              type: C<C<dynamic>>
+          returnType: void
+''');
+  }
+
+  test_typedef_legacy_notSimplyBounded_dependency_via_return_type() async {
+    // F is considered "not simply bounded" because it expands to a type that
+    // refers to C, which is not simply bounded.
+    var library = await checkLibrary('''
+typedef C F();
+class C<T extends C<T>> {}
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      notSimplyBounded class C @21
+        typeParameters
+          covariant T @23
+            bound: C<T>
+            defaultType: C<dynamic>
+        constructors
+          synthetic @-1
+    typeAliases
+      functionTypeAliasBased notSimplyBounded F @10
+        aliasedType: C<C<dynamic>> Function()
+        aliasedElement: GenericFunctionTypeElement
+          returnType: C<C<dynamic>>
+''');
+  }
+
+  test_typedef_legacy_notSimplyBounded_self() async {
+    var library = await checkLibrary('''
+typedef void F<T extends F>();
 ''');
     checkElementText(library, r'''
 library
   definingUnit
     typeAliases
-      F @8
-        aliasedType: int
-    topLevelVariables
-      static f @19
-        type: int
-          aliasElement: self::@typeAlias::F
-    accessors
-      synthetic static get f @-1
-        returnType: int
-          aliasElement: self::@typeAlias::F
-      synthetic static set f @-1
-        parameters
-          requiredPositional _f @-1
-            type: int
-              aliasElement: self::@typeAlias::F
-        returnType: void
+      functionTypeAliasBased notSimplyBounded F @13
+        typeParameters
+          unrelated T @15
+            bound: dynamic
+            defaultType: dynamic
+        aliasedType: void Function()
+        aliasedElement: GenericFunctionTypeElement
+          returnType: void
+''');
+  }
+
+  test_typedef_legacy_notSimplyBounded_simple_because_non_generic() async {
+    var library = await checkLibrary('''
+typedef void F();
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased F @13
+        aliasedType: void Function()
+        aliasedElement: GenericFunctionTypeElement
+          returnType: void
+''');
+  }
+
+  test_typedef_legacy_notSimplyBounded_simple_no_bounds() async {
+    var library = await checkLibrary('typedef void F<T>();');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased F @13
+        typeParameters
+          unrelated T @15
+            defaultType: dynamic
+        aliasedType: void Function()
+        aliasedElement: GenericFunctionTypeElement
+          returnType: void
+''');
+  }
+
+  test_typedef_legacy_parameter_hasImplicitType() async {
+    var library = await checkLibrary(r'''
+typedef void F(int a, b, [int c, d]);
+''');
+    var F = library.definingCompilationUnit.typeAliases.single;
+    var function = F.aliasedElement as GenericFunctionTypeElement;
+    // TODO(scheglov) Use better textual presentation with all information.
+    expect(function.parameters[0].hasImplicitType, false);
+    expect(function.parameters[1].hasImplicitType, true);
+    expect(function.parameters[2].hasImplicitType, false);
+    expect(function.parameters[3].hasImplicitType, true);
+  }
+
+  test_typedef_legacy_parameter_parameters() async {
+    var library = await checkLibrary('typedef F(g(x, y));');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased F @8
+        aliasedType: dynamic Function(dynamic Function(dynamic, dynamic))
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional g @10
+              type: dynamic Function(dynamic, dynamic)
+              parameters
+                requiredPositional x @12
+                  type: dynamic
+                requiredPositional y @15
+                  type: dynamic
+          returnType: dynamic
+''');
+  }
+
+  test_typedef_legacy_parameter_parameters_in_generic_class() async {
+    var library = await checkLibrary('typedef F<A, B>(A g(B x));');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased F @8
+        typeParameters
+          contravariant A @10
+            defaultType: dynamic
+          covariant B @13
+            defaultType: dynamic
+        aliasedType: dynamic Function(A Function(B))
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional g @18
+              type: A Function(B)
+              parameters
+                requiredPositional x @22
+                  type: B
+          returnType: dynamic
+''');
+  }
+
+  test_typedef_legacy_parameter_return_type() async {
+    var library = await checkLibrary('typedef F(int g());');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased F @8
+        aliasedType: dynamic Function(int Function())
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional g @14
+              type: int Function()
+          returnType: dynamic
+''');
+  }
+
+  test_typedef_legacy_parameter_type() async {
+    var library = await checkLibrary('typedef F(int i);');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased F @8
+        aliasedType: dynamic Function(int)
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional i @14
+              type: int
+          returnType: dynamic
+''');
+  }
+
+  test_typedef_legacy_parameter_type_generic() async {
+    var library = await checkLibrary('typedef F<T>(T t);');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased F @8
+        typeParameters
+          contravariant T @10
+            defaultType: dynamic
+        aliasedType: dynamic Function(T)
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional t @15
+              type: T
+          returnType: dynamic
+''');
+  }
+
+  test_typedef_legacy_parameters() async {
+    var library = await checkLibrary('typedef F(x, y);');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased F @8
+        aliasedType: dynamic Function(dynamic, dynamic)
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional x @10
+              type: dynamic
+            requiredPositional y @13
+              type: dynamic
+          returnType: dynamic
+''');
+  }
+
+  test_typedef_legacy_parameters_named() async {
+    var library = await checkLibrary('typedef F({y, z, x});');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased F @8
+        aliasedType: dynamic Function({dynamic x, dynamic y, dynamic z})
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            optionalNamed y @11
+              type: dynamic
+            optionalNamed z @14
+              type: dynamic
+            optionalNamed x @17
+              type: dynamic
+          returnType: dynamic
+''');
+  }
+
+  test_typedef_legacy_return_type() async {
+    var library = await checkLibrary('typedef int F();');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased F @12
+        aliasedType: int Function()
+        aliasedElement: GenericFunctionTypeElement
+          returnType: int
+''');
+  }
+
+  test_typedef_legacy_return_type_generic() async {
+    var library = await checkLibrary('typedef T F<T>();');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased F @10
+        typeParameters
+          covariant T @12
+            defaultType: dynamic
+        aliasedType: T Function()
+        aliasedElement: GenericFunctionTypeElement
+          returnType: T
+''');
+  }
+
+  test_typedef_legacy_return_type_implicit() async {
+    var library = await checkLibrary('typedef F();');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased F @8
+        aliasedType: dynamic Function()
+        aliasedElement: GenericFunctionTypeElement
+          returnType: dynamic
+''');
+  }
+
+  test_typedef_legacy_return_type_void() async {
+    var library = await checkLibrary('typedef void F();');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased F @13
+        aliasedType: void Function()
+        aliasedElement: GenericFunctionTypeElement
+          returnType: void
+''');
+  }
+
+  test_typedef_legacy_typeParameters() async {
+    var library = await checkLibrary('typedef U F<T, U>(T t);');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased F @10
+        typeParameters
+          contravariant T @12
+            defaultType: dynamic
+          covariant U @15
+            defaultType: dynamic
+        aliasedType: U Function(T)
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional t @20
+              type: T
+          returnType: U
+''');
+  }
+
+  test_typedef_legacy_typeParameters_bound() async {
+    var library = await checkLibrary(
+        'typedef U F<T extends Object, U extends D>(T t); class D {}');
+    checkElementText(library, r'''
+library
+  definingUnit
+    classes
+      class D @55
+        constructors
+          synthetic @-1
+    typeAliases
+      functionTypeAliasBased F @10
+        typeParameters
+          contravariant T @12
+            bound: Object
+            defaultType: Object
+          covariant U @30
+            bound: D
+            defaultType: D
+        aliasedType: U Function(T)
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional t @45
+              type: T
+          returnType: U
+''');
+  }
+
+  test_typedef_legacy_typeParameters_bound_recursive() async {
+    var library = await checkLibrary('typedef void F<T extends F>();');
+    // Typedefs cannot reference themselves.
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased notSimplyBounded F @13
+        typeParameters
+          unrelated T @15
+            bound: dynamic
+            defaultType: dynamic
+        aliasedType: void Function()
+        aliasedElement: GenericFunctionTypeElement
+          returnType: void
+''');
+  }
+
+  test_typedef_legacy_typeParameters_bound_recursive2() async {
+    var library = await checkLibrary('typedef void F<T extends List<F>>();');
+    // Typedefs cannot reference themselves.
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased notSimplyBounded F @13
+        typeParameters
+          unrelated T @15
+            bound: List<dynamic>
+            defaultType: dynamic
+        aliasedType: void Function()
+        aliasedElement: GenericFunctionTypeElement
+          returnType: void
+''');
+  }
+
+  test_typedef_legacy_typeParameters_f_bound_complex() async {
+    var library = await checkLibrary('typedef U F<T extends List<U>, U>(T t);');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased notSimplyBounded F @10
+        typeParameters
+          contravariant T @12
+            bound: List<U>
+            defaultType: List<Never>
+          covariant U @31
+            defaultType: dynamic
+        aliasedType: U Function(T)
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional t @36
+              type: T
+          returnType: U
+''');
+  }
+
+  test_typedef_legacy_typeParameters_f_bound_complex_legacy() async {
+    featureSet = FeatureSets.language_2_9;
+    var library = await checkLibrary('typedef U F<T extends List<U>, U>(T t);');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased notSimplyBounded F @10
+        typeParameters
+          contravariant T @12
+            bound: List<U*>*
+            defaultType: List<Null*>*
+          covariant U @31
+            defaultType: dynamic
+        aliasedType: U* Function(T*)*
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional t @36
+              type: T*
+          returnType: U*
+''');
+  }
+
+  test_typedef_legacy_typeParameters_f_bound_simple() async {
+    var library = await checkLibrary('typedef U F<T extends U, U>(T t);');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased notSimplyBounded F @10
+        typeParameters
+          contravariant T @12
+            bound: U
+            defaultType: Never
+          covariant U @25
+            defaultType: dynamic
+        aliasedType: U Function(T)
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional t @30
+              type: T
+          returnType: U
+''');
+  }
+
+  test_typedef_legacy_typeParameters_f_bound_simple_legacy() async {
+    featureSet = FeatureSets.language_2_9;
+    var library = await checkLibrary('typedef U F<T extends U, U>(T t);');
+    checkElementText(library, r'''
+library
+  definingUnit
+    typeAliases
+      functionTypeAliasBased notSimplyBounded F @10
+        typeParameters
+          contravariant T @12
+            bound: U*
+            defaultType: Null*
+          covariant U @25
+            defaultType: dynamic
+        aliasedType: U* Function(T*)*
+        aliasedElement: GenericFunctionTypeElement
+          parameters
+            requiredPositional t @30
+              type: T*
+          returnType: U*
 ''');
   }
 
@@ -31668,6 +32761,9 @@
           aliasElement: self::@typeAlias::X
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {T: int}
     typeAliases
       X @8
         aliasedType: A<int>
@@ -31697,6 +32793,9 @@
             A<int>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {T: int}
     typeAliases
       X @8
         typeParameters
@@ -31770,6 +32869,9 @@
           aliasElement: self::@typeAlias::X
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {T: int?}
     typeAliases
       X @8
         aliasedType: A<int?>
@@ -32074,569 +33176,6 @@
 ''');
   }
 
-  test_typedef_notSimplyBounded_dependency_via_param_type_new_style_name_included() async {
-    // F is considered "not simply bounded" because it expands to a type that
-    // refers to C, which is not simply bounded.
-    var library = await checkLibrary('''
-typedef F = void Function(C c);
-class C<T extends C<T>> {}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      notSimplyBounded class C @38
-        typeParameters
-          covariant T @40
-            bound: C<T>
-            defaultType: C<dynamic>
-        constructors
-          synthetic @-1
-    typeAliases
-      notSimplyBounded F @8
-        aliasedType: void Function(C<C<dynamic>>)
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional c @28
-              type: C<C<dynamic>>
-          returnType: void
-''');
-  }
-
-  test_typedef_notSimplyBounded_dependency_via_param_type_new_style_name_omitted() async {
-    // F is considered "not simply bounded" because it expands to a type that
-    // refers to C, which is not simply bounded.
-    var library = await checkLibrary('''
-typedef F = void Function(C);
-class C<T extends C<T>> {}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      notSimplyBounded class C @36
-        typeParameters
-          covariant T @38
-            bound: C<T>
-            defaultType: C<dynamic>
-        constructors
-          synthetic @-1
-    typeAliases
-      notSimplyBounded F @8
-        aliasedType: void Function(C<C<dynamic>>)
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional @-1
-              type: C<C<dynamic>>
-          returnType: void
-''');
-  }
-
-  test_typedef_notSimplyBounded_dependency_via_param_type_old_style() async {
-    // F is considered "not simply bounded" because it expands to a type that
-    // refers to C, which is not simply bounded.
-    var library = await checkLibrary('''
-typedef void F(C c);
-class C<T extends C<T>> {}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      notSimplyBounded class C @27
-        typeParameters
-          covariant T @29
-            bound: C<T>
-            defaultType: C<dynamic>
-        constructors
-          synthetic @-1
-    typeAliases
-      functionTypeAliasBased notSimplyBounded F @13
-        aliasedType: void Function(C<C<dynamic>>)
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional c @17
-              type: C<C<dynamic>>
-          returnType: void
-''');
-  }
-
-  test_typedef_notSimplyBounded_dependency_via_return_type_new_style() async {
-    // F is considered "not simply bounded" because it expands to a type that
-    // refers to C, which is not simply bounded.
-    var library = await checkLibrary('''
-typedef F = C Function();
-class C<T extends C<T>> {}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      notSimplyBounded class C @32
-        typeParameters
-          covariant T @34
-            bound: C<T>
-            defaultType: C<dynamic>
-        constructors
-          synthetic @-1
-    typeAliases
-      notSimplyBounded F @8
-        aliasedType: C<C<dynamic>> Function()
-        aliasedElement: GenericFunctionTypeElement
-          returnType: C<C<dynamic>>
-''');
-  }
-
-  test_typedef_notSimplyBounded_dependency_via_return_type_old_style() async {
-    // F is considered "not simply bounded" because it expands to a type that
-    // refers to C, which is not simply bounded.
-    var library = await checkLibrary('''
-typedef C F();
-class C<T extends C<T>> {}
-''');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      notSimplyBounded class C @21
-        typeParameters
-          covariant T @23
-            bound: C<T>
-            defaultType: C<dynamic>
-        constructors
-          synthetic @-1
-    typeAliases
-      functionTypeAliasBased notSimplyBounded F @10
-        aliasedType: C<C<dynamic>> Function()
-        aliasedElement: GenericFunctionTypeElement
-          returnType: C<C<dynamic>>
-''');
-  }
-
-  test_typedef_parameter_hasImplicitType() async {
-    var library = await checkLibrary(r'''
-typedef void F(int a, b, [int c, d]);
-''');
-    var F = library.definingCompilationUnit.typeAliases.single;
-    var function = F.aliasedElement as GenericFunctionTypeElement;
-    // TODO(scheglov) Use better textual presentation with all information.
-    expect(function.parameters[0].hasImplicitType, false);
-    expect(function.parameters[1].hasImplicitType, true);
-    expect(function.parameters[2].hasImplicitType, false);
-    expect(function.parameters[3].hasImplicitType, true);
-  }
-
-  test_typedef_parameter_parameters() async {
-    var library = await checkLibrary('typedef F(g(x, y));');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased F @8
-        aliasedType: dynamic Function(dynamic Function(dynamic, dynamic))
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional g @10
-              type: dynamic Function(dynamic, dynamic)
-              parameters
-                requiredPositional x @12
-                  type: dynamic
-                requiredPositional y @15
-                  type: dynamic
-          returnType: dynamic
-''');
-  }
-
-  test_typedef_parameter_parameters_in_generic_class() async {
-    var library = await checkLibrary('typedef F<A, B>(A g(B x));');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased F @8
-        typeParameters
-          contravariant A @10
-            defaultType: dynamic
-          covariant B @13
-            defaultType: dynamic
-        aliasedType: dynamic Function(A Function(B))
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional g @18
-              type: A Function(B)
-              parameters
-                requiredPositional x @22
-                  type: B
-          returnType: dynamic
-''');
-  }
-
-  test_typedef_parameter_return_type() async {
-    var library = await checkLibrary('typedef F(int g());');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased F @8
-        aliasedType: dynamic Function(int Function())
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional g @14
-              type: int Function()
-          returnType: dynamic
-''');
-  }
-
-  test_typedef_parameter_type() async {
-    var library = await checkLibrary('typedef F(int i);');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased F @8
-        aliasedType: dynamic Function(int)
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional i @14
-              type: int
-          returnType: dynamic
-''');
-  }
-
-  test_typedef_parameter_type_generic() async {
-    var library = await checkLibrary('typedef F<T>(T t);');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased F @8
-        typeParameters
-          contravariant T @10
-            defaultType: dynamic
-        aliasedType: dynamic Function(T)
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional t @15
-              type: T
-          returnType: dynamic
-''');
-  }
-
-  test_typedef_parameters() async {
-    var library = await checkLibrary('typedef F(x, y);');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased F @8
-        aliasedType: dynamic Function(dynamic, dynamic)
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional x @10
-              type: dynamic
-            requiredPositional y @13
-              type: dynamic
-          returnType: dynamic
-''');
-  }
-
-  test_typedef_parameters_named() async {
-    var library = await checkLibrary('typedef F({y, z, x});');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased F @8
-        aliasedType: dynamic Function({dynamic x, dynamic y, dynamic z})
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            optionalNamed y @11
-              type: dynamic
-            optionalNamed z @14
-              type: dynamic
-            optionalNamed x @17
-              type: dynamic
-          returnType: dynamic
-''');
-  }
-
-  test_typedef_return_type() async {
-    var library = await checkLibrary('typedef int F();');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased F @12
-        aliasedType: int Function()
-        aliasedElement: GenericFunctionTypeElement
-          returnType: int
-''');
-  }
-
-  test_typedef_return_type_generic() async {
-    var library = await checkLibrary('typedef T F<T>();');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased F @10
-        typeParameters
-          covariant T @12
-            defaultType: dynamic
-        aliasedType: T Function()
-        aliasedElement: GenericFunctionTypeElement
-          returnType: T
-''');
-  }
-
-  test_typedef_return_type_implicit() async {
-    var library = await checkLibrary('typedef F();');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased F @8
-        aliasedType: dynamic Function()
-        aliasedElement: GenericFunctionTypeElement
-          returnType: dynamic
-''');
-  }
-
-  test_typedef_return_type_void() async {
-    var library = await checkLibrary('typedef void F();');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased F @13
-        aliasedType: void Function()
-        aliasedElement: GenericFunctionTypeElement
-          returnType: void
-''');
-  }
-
-  test_typedef_type_parameters() async {
-    var library = await checkLibrary('typedef U F<T, U>(T t);');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased F @10
-        typeParameters
-          contravariant T @12
-            defaultType: dynamic
-          covariant U @15
-            defaultType: dynamic
-        aliasedType: U Function(T)
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional t @20
-              type: T
-          returnType: U
-''');
-  }
-
-  test_typedef_type_parameters_bound() async {
-    var library = await checkLibrary(
-        'typedef U F<T extends Object, U extends D>(T t); class D {}');
-    checkElementText(library, r'''
-library
-  definingUnit
-    classes
-      class D @55
-        constructors
-          synthetic @-1
-    typeAliases
-      functionTypeAliasBased F @10
-        typeParameters
-          contravariant T @12
-            bound: Object
-            defaultType: Object
-          covariant U @30
-            bound: D
-            defaultType: D
-        aliasedType: U Function(T)
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional t @45
-              type: T
-          returnType: U
-''');
-  }
-
-  test_typedef_type_parameters_bound_recursive() async {
-    var library = await checkLibrary('typedef void F<T extends F>();');
-    // Typedefs cannot reference themselves.
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased notSimplyBounded F @13
-        typeParameters
-          unrelated T @15
-            bound: dynamic
-            defaultType: dynamic
-        aliasedType: void Function()
-        aliasedElement: GenericFunctionTypeElement
-          returnType: void
-''');
-  }
-
-  test_typedef_type_parameters_bound_recursive2() async {
-    var library = await checkLibrary('typedef void F<T extends List<F>>();');
-    // Typedefs cannot reference themselves.
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased notSimplyBounded F @13
-        typeParameters
-          unrelated T @15
-            bound: List<dynamic>
-            defaultType: dynamic
-        aliasedType: void Function()
-        aliasedElement: GenericFunctionTypeElement
-          returnType: void
-''');
-  }
-
-  test_typedef_type_parameters_f_bound_complex() async {
-    var library = await checkLibrary('typedef U F<T extends List<U>, U>(T t);');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased notSimplyBounded F @10
-        typeParameters
-          contravariant T @12
-            bound: List<U>
-            defaultType: List<Never>
-          covariant U @31
-            defaultType: dynamic
-        aliasedType: U Function(T)
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional t @36
-              type: T
-          returnType: U
-''');
-  }
-
-  test_typedef_type_parameters_f_bound_complex_legacy() async {
-    featureSet = FeatureSets.language_2_9;
-    var library = await checkLibrary('typedef U F<T extends List<U>, U>(T t);');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased notSimplyBounded F @10
-        typeParameters
-          contravariant T @12
-            bound: List<U*>*
-            defaultType: List<Null*>*
-          covariant U @31
-            defaultType: dynamic
-        aliasedType: U* Function(T*)*
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional t @36
-              type: T*
-          returnType: U*
-''');
-  }
-
-  test_typedef_type_parameters_f_bound_simple() async {
-    var library = await checkLibrary('typedef U F<T extends U, U>(T t);');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased notSimplyBounded F @10
-        typeParameters
-          contravariant T @12
-            bound: U
-            defaultType: Never
-          covariant U @25
-            defaultType: dynamic
-        aliasedType: U Function(T)
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional t @30
-              type: T
-          returnType: U
-''');
-  }
-
-  test_typedef_type_parameters_f_bound_simple_legacy() async {
-    featureSet = FeatureSets.language_2_9;
-    var library = await checkLibrary('typedef U F<T extends U, U>(T t);');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      functionTypeAliasBased notSimplyBounded F @10
-        typeParameters
-          contravariant T @12
-            bound: U*
-            defaultType: Null*
-          covariant U @25
-            defaultType: dynamic
-        aliasedType: U* Function(T*)*
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional t @30
-              type: T*
-          returnType: U*
-''');
-  }
-
-  test_typedef_type_parameters_f_bound_simple_new_syntax() async {
-    var library =
-        await checkLibrary('typedef F<T extends U, U> = U Function(T t);');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      notSimplyBounded F @8
-        typeParameters
-          contravariant T @10
-            bound: U
-            defaultType: Never
-          covariant U @23
-            defaultType: dynamic
-        aliasedType: U Function(T)
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional t @41
-              type: T
-          returnType: U
-''');
-  }
-
-  test_typedef_type_parameters_f_bound_simple_new_syntax_legacy() async {
-    featureSet = FeatureSets.language_2_9;
-    var library =
-        await checkLibrary('typedef F<T extends U, U> = U Function(T t);');
-    checkElementText(library, r'''
-library
-  definingUnit
-    typeAliases
-      notSimplyBounded F @8
-        typeParameters
-          contravariant T @10
-            bound: U*
-            defaultType: Null*
-          covariant U @23
-            defaultType: dynamic
-        aliasedType: U* Function(T*)*
-        aliasedElement: GenericFunctionTypeElement
-          parameters
-            requiredPositional t @41
-              type: T*
-          returnType: U*
-''');
-  }
-
   test_typedefs() async {
     var library = await checkLibrary('f() {} g() {}');
     checkElementText(library, r'''
diff --git a/pkg/analyzer/test/src/summary/top_level_inference_test.dart b/pkg/analyzer/test/src/summary/top_level_inference_test.dart
index feb2509..7a9a91c 100644
--- a/pkg/analyzer/test/src/summary/top_level_inference_test.dart
+++ b/pkg/analyzer/test/src/summary/top_level_inference_test.dart
@@ -1661,6 +1661,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           foo @52
             returnType: int
@@ -4712,6 +4713,9 @@
             type: List<dynamic Function()>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {T: int}
         accessors
           get x @114
             returnType: dynamic Function()
@@ -4898,6 +4902,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           m @58
             parameters
@@ -4949,6 +4954,7 @@
           B
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           m @100
             typeInferenceError: overrideNoCombinedSuperSignature
@@ -5099,6 +5105,7 @@
           B
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           m @88
             typeInferenceError: overrideNoCombinedSuperSignature
@@ -5152,6 +5159,9 @@
           B<double>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {T: int}
         methods
           m @112
             typeInferenceError: overrideNoCombinedSuperSignature
@@ -5210,6 +5220,9 @@
           B<double>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {K: int, V: String}
         methods
           m @119
             typeInferenceError: overrideNoCombinedSuperSignature
@@ -5246,6 +5259,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           m @53
             parameters
@@ -5283,6 +5297,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           m @53
             parameters
@@ -5320,6 +5335,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           m @44
             parameters
@@ -5355,6 +5371,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           m @63
             parameters
@@ -5395,6 +5412,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           m @48
             parameters
@@ -5439,10 +5457,16 @@
         supertype: A<int, T>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {K: int, V: T}
       class C @70
         supertype: B<String>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::B::@constructor::•
+              substitution: {T: String}
         methods
           m @94
             parameters
@@ -5481,6 +5505,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           m @55
             parameters
@@ -5491,6 +5516,7 @@
         supertype: B
         constructors
           synthetic @-1
+            superConstructor: self::@class::B::@constructor::•
         methods
           m @87
             parameters
@@ -5540,6 +5566,7 @@
         supertype: B
         constructors
           synthetic @-1
+            superConstructor: self::@class::B::@constructor::•
         methods
           m @90
             parameters
@@ -5590,6 +5617,7 @@
         supertype: B
         constructors
           synthetic @-1
+            superConstructor: self::@class::B::@constructor::•
         methods
           m @99
             parameters
@@ -5632,6 +5660,9 @@
         supertype: A<int, String>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {K: int, V: String}
         methods
           m @77
             parameters
@@ -5669,6 +5700,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           m @55
             parameters
@@ -5706,6 +5738,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           m @67
             parameters
@@ -5745,6 +5778,7 @@
         supertype: A
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           m @67
             parameters
@@ -5791,10 +5825,16 @@
         supertype: A<int, T>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {K: int, V: T}
       class C @70
         supertype: B<String>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::B::@constructor::•
+              substitution: {T: String}
         methods
           m @94
             parameters
@@ -5918,6 +5958,9 @@
         supertype: A<T2, T1>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {K: T2, V: T1}
       class C @91
         interfaces
           B<int, String>
@@ -5962,6 +6005,7 @@
         supertype: A1
         constructors
           synthetic @-1
+            superConstructor: self::@class::A1::@constructor::•
         methods
           _foo @77
             returnType: int
@@ -6053,6 +6097,9 @@
           B<String>
         constructors
           synthetic @-1
+            superConstructor: ConstructorMember
+              base: self::@class::A::@constructor::•
+              substitution: {K: int, V: String}
         methods
           m @119
             parameters
@@ -6102,6 +6149,7 @@
           B
         constructors
           synthetic @-1
+            superConstructor: self::@class::A::@constructor::•
         methods
           m @101
             parameters
diff --git a/pkg/analyzer/test/src/test_all.dart b/pkg/analyzer/test/src/test_all.dart
index 9969e39..c6fe9f8 100644
--- a/pkg/analyzer/test/src/test_all.dart
+++ b/pkg/analyzer/test/src/test_all.dart
@@ -4,6 +4,7 @@
 
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
+import 'clients/test_all.dart' as clients;
 import 'context/test_all.dart' as context;
 import 'dart/test_all.dart' as dart;
 import 'dartdoc/test_all.dart' as dartdoc;
@@ -25,6 +26,7 @@
 
 main() {
   defineReflectiveSuite(() {
+    clients.main();
     context.main();
     dart.main();
     dartdoc.main();
diff --git a/pkg/analyzer/tool/diagnostics/diagnostics.md b/pkg/analyzer/tool/diagnostics/diagnostics.md
index 97d64c9..8f8c3aa 100644
--- a/pkg/analyzer/tool/diagnostics/diagnostics.md
+++ b/pkg/analyzer/tool/diagnostics/diagnostics.md
@@ -1323,7 +1323,7 @@
 ### body_might_complete_normally
 
 _The body might complete normally, causing 'null' to be returned, but the return
-type is a potentially non-nullable type._
+type, '{0}', is a potentially non-nullable type._
 
 #### Description
 
@@ -1384,13 +1384,15 @@
 }
 {% endprettify %}
 
-If the method intentionally returns `null` at the end, then change the
+If the method intentionally returns `null` at the end, then add an
+explicit return of `null` at the end of the method and change the
 return type so that it's valid to return `null`:
 
 {% prettify dart tag=pre+code %}
 class C<T> {
   T? m(T t) {
     print(t);
+    return null;
   }
 }
 {% endprettify %}
diff --git a/pkg/analyzer/tool/messages/error_code_info.dart b/pkg/analyzer/tool/messages/error_code_info.dart
index e89d24d..038257d 100644
--- a/pkg/analyzer/tool/messages/error_code_info.dart
+++ b/pkg/analyzer/tool/messages/error_code_info.dart
@@ -192,6 +192,46 @@
   return decodeCfeMessagesYaml(messagesYaml);
 }
 
+/// Splits [text] on spaces using the given [maxWidth] (and [firstLineWidth] if
+/// given).
+List<String> _splitText(
+  String text, {
+  required int maxWidth,
+  int? firstLineWidth,
+}) {
+  firstLineWidth ??= maxWidth;
+  var lines = <String>[];
+  // The character width to use as a maximum width. This starts as
+  // [firstLineWidth] but becomes [maxWidth] on every iteration after the first.
+  var width = firstLineWidth;
+  var lineMaxEndIndex = width;
+  var lineStartIndex = 0;
+
+  while (true) {
+    if (lineMaxEndIndex >= text.length) {
+      lines.add(text.substring(lineStartIndex, text.length));
+      break;
+    } else {
+      var lastSpaceIndex = text.lastIndexOf(' ', lineMaxEndIndex);
+      if (lastSpaceIndex == -1 || lastSpaceIndex <= lineStartIndex) {
+        // No space between [lineStartIndex] and [lineMaxEndIndex]. Get the
+        // _next_ space.
+        lastSpaceIndex = text.indexOf(' ', lineMaxEndIndex);
+        if (lastSpaceIndex == -1) {
+          // No space at all after [lineStartIndex].
+          lines.add(text.substring(lineStartIndex));
+          break;
+        }
+      }
+      lines.add(text.substring(lineStartIndex, lastSpaceIndex + 1));
+      lineStartIndex = lastSpaceIndex + 1;
+      width = maxWidth;
+    }
+    lineMaxEndIndex = lineStartIndex + maxWidth;
+  }
+  return lines;
+}
+
 /// In-memory representation of error code information obtained from the
 /// analyzer's `messages.yaml` file.
 class AnalyzerErrorCodeInfo extends ErrorCodeInfo {
@@ -431,16 +471,21 @@
     var out = StringBuffer();
     out.writeln('$className(');
     out.writeln("'${sharedName ?? errorCode}',");
+    var maxWidth = 80 - 8 /* indentation */ - 2 /* quotes */ - 1 /* comma */;
     final placeholderToIndexMap = computePlaceholderToIndexMap();
-    out.writeln(
-        json.encode(convertTemplate(placeholderToIndexMap, problemMessage)) +
-            ',');
+    var messageAsCode = convertTemplate(placeholderToIndexMap, problemMessage);
+    out.writeln(_splitText(messageAsCode,
+                maxWidth: maxWidth, firstLineWidth: maxWidth + 4)
+            .map(json.encode)
+            .join('\n') +
+        ',');
     final correctionMessage = this.correctionMessage;
     if (correctionMessage is String) {
       out.write('correctionMessage: ');
-      out.writeln(json.encode(
-              convertTemplate(placeholderToIndexMap, correctionMessage)) +
-          ',');
+      var code = convertTemplate(placeholderToIndexMap, correctionMessage);
+      out.writeln(
+          _splitText(code, maxWidth: maxWidth).map(json.encode).join('\n') +
+              ',');
     }
     if (hasPublishedDocs) {
       out.writeln('hasPublishedDocs:true,');
diff --git a/pkg/analyzer_cli/analysis_options.yaml b/pkg/analyzer_cli/analysis_options.yaml
index 069c2d2..8d202f9 100644
--- a/pkg/analyzer_cli/analysis_options.yaml
+++ b/pkg/analyzer_cli/analysis_options.yaml
@@ -1,9 +1,8 @@
 include: package:lints/recommended.yaml
 
 analyzer:
-  strong-mode:
-    implicit-casts: false
   language:
+    strict-casts: true
     strict-inference: true
   exclude:
     - test/data/**
diff --git a/pkg/analyzer_cli/lib/src/driver.dart b/pkg/analyzer_cli/lib/src/driver.dart
index b2dd53f..de1d3c0 100644
--- a/pkg/analyzer_cli/lib/src/driver.dart
+++ b/pkg/analyzer_cli/lib/src/driver.dart
@@ -17,8 +17,6 @@
 import 'package:analyzer/src/dart/analysis/file_state.dart';
 import 'package:analyzer/src/dart/analysis/results.dart';
 import 'package:analyzer/src/generated/engine.dart';
-import 'package:analyzer/src/generated/interner.dart';
-import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/lint/linter.dart';
 import 'package:analyzer/src/lint/pub.dart';
@@ -95,8 +93,6 @@
     _isStarted = true;
     var startTime = DateTime.now().millisecondsSinceEpoch;
 
-    StringUtilities.INTERNER = MappedInterner();
-
     linter.registerLintRules();
 
     // Parse commandline options.
diff --git a/pkg/analyzer_plugin/CHANGELOG.md b/pkg/analyzer_plugin/CHANGELOG.md
index 04ab329..ca17b41 100644
--- a/pkg/analyzer_plugin/CHANGELOG.md
+++ b/pkg/analyzer_plugin/CHANGELOG.md
@@ -1,3 +1,6 @@
+## 0.9.0
+- Support version `3.x` of the `analyzer` package
+
 ## 0.8.0
 - Require SDK `2.14` to use `Object.hash()`.
 - Require `yaml 3.1.0` to use `recover`.
diff --git a/pkg/analyzer_plugin/analysis_options.yaml b/pkg/analyzer_plugin/analysis_options.yaml
index c183e26..a8cb96f 100644
--- a/pkg/analyzer_plugin/analysis_options.yaml
+++ b/pkg/analyzer_plugin/analysis_options.yaml
@@ -1,6 +1,6 @@
 analyzer:
-  strong-mode:
-    implicit-casts: false
+  language:
+    strict-casts: true
 linter:
   rules:
     - await_only_futures
diff --git a/pkg/analyzer_plugin/lib/src/utilities/change_builder/change_builder_core.dart b/pkg/analyzer_plugin/lib/src/utilities/change_builder/change_builder_core.dart
index d2d24b8..ebb810a 100644
--- a/pkg/analyzer_plugin/lib/src/utilities/change_builder/change_builder_core.dart
+++ b/pkg/analyzer_plugin/lib/src/utilities/change_builder/change_builder_core.dart
@@ -130,6 +130,13 @@
     if (builder == null) {
       builder = await _createDartFileEditBuilder(path);
       if (builder != null) {
+        // It's not currently supported to call this method twice concurrently
+        // for the same file as two builder may be produced because of the above
+        // `await` so detect this and throw to avoid losing edits.
+        if (_dartFileEditBuilders.containsKey(path)) {
+          throw StateError(
+              "Can't add multiple edits concurrently for the same file");
+        }
         _dartFileEditBuilders[path] = builder;
       }
     }
diff --git a/pkg/analyzer_plugin/lib/src/utilities/change_builder/change_builder_dart.dart b/pkg/analyzer_plugin/lib/src/utilities/change_builder/change_builder_dart.dart
index 104fc79..23110a9 100644
--- a/pkg/analyzer_plugin/lib/src/utilities/change_builder/change_builder_dart.dart
+++ b/pkg/analyzer_plugin/lib/src/utilities/change_builder/change_builder_dart.dart
@@ -1486,9 +1486,9 @@
       return;
     }
 
-    addReplacement(range.node(typeAnnotation!), (EditBuilder builder) {
+    addReplacement(range.node(typeAnnotation!), (builder) {
       var futureType = typeProvider.futureType(type);
-      if (!(builder as DartEditBuilder).writeType(futureType)) {
+      if (!builder.writeType(futureType)) {
         builder.write('void');
       }
     });
diff --git a/pkg/analyzer_plugin/lib/src/utilities/completion/completion_target.dart b/pkg/analyzer_plugin/lib/src/utilities/completion/completion_target.dart
index bb03fc8..e235487 100644
--- a/pkg/analyzer_plugin/lib/src/utilities/completion/completion_target.dart
+++ b/pkg/analyzer_plugin/lib/src/utilities/completion/completion_target.dart
@@ -3,7 +3,6 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:analyzer/dart/ast/ast.dart';
-import 'package:analyzer/dart/ast/standard_ast_factory.dart';
 import 'package:analyzer/dart/ast/syntactic_entity.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element.dart';
@@ -262,6 +261,7 @@
         return node.prefix;
       }
     }
+    return null;
   }
 
   /// If the target is an argument in an argument list, and the invocation is
@@ -285,6 +285,8 @@
         executable = invocation.constructorName.staticElement;
       } else if (invocation is MethodInvocation) {
         executable = invocation.methodName.staticElement;
+      } else if (invocation is RedirectingConstructorInvocation) {
+        executable = invocation.staticElement;
       } else if (invocation is SuperConstructorInvocation) {
         executable = invocation.staticElement;
       }
@@ -340,6 +342,37 @@
     return false;
   }
 
+  /// Return `true` if the [offset] is followed by a comma.
+  bool get isFollowedByComma {
+    // f(^); NO
+    // f(one: 1, ^); NO
+    // f(^ , one: 1); YES
+    // f(^, one: 1); YES
+    // f(^ one: 1); NO
+
+    bool isExistingComma(Token? token) {
+      return token != null &&
+          !token.isSynthetic &&
+          token.type == TokenType.COMMA;
+    }
+
+    var entity = this.entity;
+
+    Token token;
+    if (entity is AstNode) {
+      token = entity.endToken;
+    } else if (entity is Token) {
+      token = entity;
+    } else {
+      return false;
+    }
+
+    if (token.offset <= offset && offset <= token.end) {
+      return isExistingComma(token.next);
+    }
+    return isExistingComma(token);
+  }
+
   /// If the target is an argument in an argument list, and the invocation is
   /// resolved, return the corresponding [ParameterElement].
   ParameterElement? get parameterElement {
@@ -379,15 +412,21 @@
         }
       }
       if (token is StringToken) {
-        var uri = astFactory.simpleStringLiteral(token, token.lexeme);
-        var keyword = containingNode.findPrevious(token)?.keyword;
-        if (keyword == Keyword.IMPORT ||
-            keyword == Keyword.EXPORT ||
-            keyword == Keyword.PART) {
+        final containingNode = this.containingNode;
+        StringLiteral? uri;
+        Directive? directive;
+        if (containingNode is NamespaceDirective) {
+          directive = containingNode;
+          uri = containingNode.uri;
+        } else if (containingNode is SimpleStringLiteral) {
+          uri = containingNode;
+          directive = containingNode.parent.ifTypeOrNull();
+        }
+        // Replacement range for a URI.
+        if (directive != null && uri is SimpleStringLiteral) {
           var start = uri.contentsOffset;
           var end = uri.contentsEnd;
           if (start <= requestOffset && requestOffset <= end) {
-            // Replacement range for import URI
             return SourceRange(start, end - start);
           }
         }
@@ -626,3 +665,11 @@
     }
   }
 }
+
+extension on Object? {
+  /// If the target is [T], return it, otherwise `null`.
+  T? ifTypeOrNull<T>() {
+    final self = this;
+    return self is T ? self : null;
+  }
+}
diff --git a/pkg/analyzer_plugin/lib/src/utilities/visitors/local_declaration_visitor.dart b/pkg/analyzer_plugin/lib/src/utilities/visitors/local_declaration_visitor.dart
index c622af3..728782a 100644
--- a/pkg/analyzer_plugin/lib/src/utilities/visitors/local_declaration_visitor.dart
+++ b/pkg/analyzer_plugin/lib/src/utilities/visitors/local_declaration_visitor.dart
@@ -3,21 +3,12 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:analyzer/dart/ast/ast.dart';
-import 'package:analyzer/dart/ast/standard_ast_factory.dart';
-import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
-import 'package:analyzer/src/dart/ast/token.dart';
 
 /// A visitor that visits an [AstNode] and its parent recursively along with any
 /// declarations in those nodes. Consumers typically call [visit] which catches
 /// the exception thrown by [finished].
 abstract class LocalDeclarationVisitor extends GeneralizingAstVisitor {
-  static final NamedType STACKTRACE_TYPE = astFactory.namedType(
-    name: astFactory.simpleIdentifier(
-      StringToken(TokenType.IDENTIFIER, 'StackTrace', 0),
-    ),
-  );
-
   final int offset;
 
   LocalDeclarationVisitor(this.offset);
@@ -81,14 +72,16 @@
 
   @override
   void visitCatchClause(CatchClause node) {
-    var param = node.exceptionParameter;
-    if (param != null) {
-      declaredParam(param, node.exceptionType);
+    var exceptionParameter = node.exceptionParameter;
+    if (exceptionParameter != null) {
+      declaredParam(exceptionParameter, node.exceptionType);
     }
-    param = node.stackTraceParameter;
-    if (param != null) {
-      declaredParam(param, STACKTRACE_TYPE);
+
+    var stackTraceParameter = node.stackTraceParameter;
+    if (stackTraceParameter != null) {
+      declaredParam(stackTraceParameter, null);
     }
+
     visitNode(node);
   }
 
diff --git a/pkg/analyzer_plugin/lib/utilities/navigation/navigation_dart.dart b/pkg/analyzer_plugin/lib/utilities/navigation/navigation_dart.dart
index 8d5106f..5ad2871 100644
--- a/pkg/analyzer_plugin/lib/utilities/navigation/navigation_dart.dart
+++ b/pkg/analyzer_plugin/lib/utilities/navigation/navigation_dart.dart
@@ -253,6 +253,52 @@
   }
 
   @override
+  void visitComment(Comment node) {
+    for (var commentReference in node.references) {
+      commentReference.accept(this);
+    }
+
+    var inToolAnnotation = false;
+    for (var token in node.tokens) {
+      if (token.isEof) {
+        break;
+      }
+      var strValue = token.toString();
+      if (strValue.isEmpty) {
+        continue;
+      }
+
+      if (inToolAnnotation) {
+        if (strValue.contains('{@end-tool}')) {
+          inToolAnnotation = false;
+        } else if (strValue.contains('** See code in ')) {
+          var startIndex = strValue.indexOf('** See code in ') + 15;
+          var endIndex = strValue.indexOf('.dart') + 5;
+          var pathSnippet = strValue.substring(startIndex, endIndex);
+          var parentPath =
+              _computeParentWithExamplesAPI(node, resourceProvider);
+          if (parentPath != null) {
+            computer.collector.addRegion(
+                token.offset + startIndex,
+                token.offset + endIndex,
+                protocol.ElementKind.LIBRARY,
+                protocol.Location(
+                    resourceProvider.pathContext.join(parentPath, pathSnippet),
+                    0,
+                    0,
+                    0,
+                    0,
+                    endLine: 0,
+                    endColumn: 0));
+          }
+        }
+      } else if (strValue.contains('{@tool ')) {
+        inToolAnnotation = true;
+      }
+    }
+  }
+
+  @override
   void visitCompilationUnit(CompilationUnit unit) {
     // prepare top-level nodes sorted by their offsets
     var nodes = <AstNode>[];
@@ -476,4 +522,31 @@
       }
     }
   }
+
+  /// Given some [Comment], compute and return the parent directory absolute
+  /// path which contains the directories 'examples/api/'. Null is returned if
+  /// such directories are not found.
+  String? _computeParentWithExamplesAPI(
+      Comment node, ResourceProvider resourceProvider) {
+    var source =
+        node.thisOrAncestorOfType<CompilationUnit>()?.declaredElement?.source;
+    if (source == null) {
+      return null;
+    }
+
+    var file = resourceProvider.getFile(source.fullName);
+    if (!file.exists) {
+      return null;
+    }
+    var parent = file.parent2;
+    while (parent != parent.parent2) {
+      var examplesFolder = parent.getChildAssumingFolder('examples');
+      if (examplesFolder.exists &&
+          examplesFolder.getChildAssumingFolder('api').exists) {
+        return parent.path;
+      }
+      parent = parent.parent2;
+    }
+    return null;
+  }
 }
diff --git a/pkg/analyzer_plugin/pubspec.yaml b/pkg/analyzer_plugin/pubspec.yaml
index 41b859d..c8b99c8 100644
--- a/pkg/analyzer_plugin/pubspec.yaml
+++ b/pkg/analyzer_plugin/pubspec.yaml
@@ -1,15 +1,15 @@
 name: analyzer_plugin
 description: A framework and support code for building plugins for the analysis server.
-version: 0.8.0
+version: 0.9.0
 homepage: https://github.com/dart-lang/sdk/tree/master/pkg/analyzer_plugin
 
 environment:
   sdk: '>=2.14.0 <3.0.0'
 
 dependencies:
-  analyzer: ^2.4.0
+  analyzer: ^3.0.0
   collection: ^1.15.0
-  dart_style: ^2.0.0
+  dart_style: ^2.2.1
   pub_semver: ^2.0.0
   yaml: ^3.1.0
 
diff --git a/pkg/analyzer_plugin/test/src/utilities/change_builder/change_builder_dart_test.dart b/pkg/analyzer_plugin/test/src/utilities/change_builder/change_builder_dart_test.dart
index 047e7a1..481147a 100644
--- a/pkg/analyzer_plugin/test/src/utilities/change_builder/change_builder_dart_test.dart
+++ b/pkg/analyzer_plugin/test/src/utilities/change_builder/change_builder_dart_test.dart
@@ -1868,6 +1868,42 @@
 ''');
   }
 
+  Future<void> test_multipleEdits_concurrently() async {
+    var initialCode = '00';
+    var path = convertPath('/home/test/lib/test.dart');
+    newFile(path, content: initialCode);
+
+    var builder = newBuilder();
+    var future = Future.wait([
+      builder.addDartFileEdit(path, (builder) {
+        builder.addSimpleInsertion(0, '11');
+      }),
+      builder.addDartFileEdit(path, (builder) {
+        builder.addSimpleInsertion(2, '22');
+      }),
+    ]);
+
+    expect(future, throwsA(TypeMatcher<StateError>()));
+  }
+
+  Future<void> test_multipleEdits_sequentially() async {
+    var initialCode = '00';
+    var path = convertPath('/home/test/lib/test.dart');
+    newFile(path, content: initialCode);
+
+    var builder = newBuilder();
+    await builder.addDartFileEdit(path, (builder) {
+      builder.addSimpleInsertion(0, '11');
+    });
+    await builder.addDartFileEdit(path, (builder) {
+      builder.addSimpleInsertion(2, '22');
+    });
+
+    var edits = getEdits(builder);
+    var resultCode = SourceEdit.applySequence(initialCode, edits);
+    expect(resultCode, '110022');
+  }
+
   Future<void> test_replaceTypeWithFuture() async {
     var path = convertPath('/home/test/lib/test.dart');
     addSource(path, 'String f() {}');
diff --git a/pkg/analyzer_plugin/test/support/abstract_single_unit.dart b/pkg/analyzer_plugin/test/support/abstract_single_unit.dart
index bdd1c69..21e8f64 100644
--- a/pkg/analyzer_plugin/test/support/abstract_single_unit.dart
+++ b/pkg/analyzer_plugin/test/support/abstract_single_unit.dart
@@ -8,7 +8,6 @@
 import 'package:analyzer/src/dart/ast/element_locator.dart';
 import 'package:analyzer/src/dart/ast/utilities.dart';
 import 'package:analyzer/src/dart/error/hint_codes.dart';
-import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/test_utilities/find_element.dart';
 import 'package:analyzer/src/test_utilities/find_node.dart';
 import 'package:test/test.dart';
@@ -39,7 +38,10 @@
         as SimpleIdentifier;
   }
 
-  AstNode? findNodeAtOffset(int offset, [Predicate<AstNode>? predicate]) {
+  AstNode? findNodeAtOffset(
+    int offset, [
+    bool Function(AstNode)? predicate,
+  ]) {
     var result = NodeLocator(offset).searchWithin(testUnit);
     if (result != null && predicate != null) {
       result = result.thisOrAncestorMatching(predicate);
@@ -47,13 +49,18 @@
     return result;
   }
 
-  AstNode? findNodeAtString(String search, [Predicate<AstNode>? predicate]) {
+  AstNode? findNodeAtString(
+    String search, [
+    bool Function(AstNode)? predicate,
+  ]) {
     var offset = findOffset(search);
     return findNodeAtOffset(offset, predicate);
   }
 
-  Element? findNodeElementAtString(String search,
-      [Predicate<AstNode>? predicate]) {
+  Element? findNodeElementAtString(
+    String search, [
+    bool Function(AstNode)? predicate,
+  ]) {
     var node = findNodeAtString(search, predicate);
     if (node == null) {
       return null;
diff --git a/pkg/analyzer_utilities/lib/check/bool.dart b/pkg/analyzer_utilities/lib/check/bool.dart
index 18d5054..1b13751 100644
--- a/pkg/analyzer_utilities/lib/check/bool.dart
+++ b/pkg/analyzer_utilities/lib/check/bool.dart
@@ -5,15 +5,15 @@
 import 'package:analyzer_utilities/check/check.dart';
 
 extension BoolExtension on CheckTarget<bool> {
-  void get isTrue {
-    if (!value) {
-      fail('is not true');
-    }
-  }
-
   void get isFalse {
     if (value) {
       fail('is not false');
     }
   }
+
+  void get isTrue {
+    if (!value) {
+      fail('is not true');
+    }
+  }
 }
diff --git a/pkg/analyzer_utilities/lib/check/check.dart b/pkg/analyzer_utilities/lib/check/check.dart
index b3147bb..54b57c9 100644
--- a/pkg/analyzer_utilities/lib/check/check.dart
+++ b/pkg/analyzer_utilities/lib/check/check.dart
@@ -10,6 +10,7 @@
 export 'package:analyzer_utilities/check/equality.dart';
 export 'package:analyzer_utilities/check/int.dart';
 export 'package:analyzer_utilities/check/iterable.dart';
+export 'package:analyzer_utilities/check/nullability.dart';
 export 'package:analyzer_utilities/check/string.dart';
 export 'package:analyzer_utilities/check/type.dart';
 
diff --git a/pkg/analyzer_utilities/lib/check/check_target.dart b/pkg/analyzer_utilities/lib/check/check_target.dart
index 1d0e608..d22a1ac 100644
--- a/pkg/analyzer_utilities/lib/check/check_target.dart
+++ b/pkg/analyzer_utilities/lib/check/check_target.dart
@@ -16,13 +16,6 @@
 
   String get _indent => '  ' * (_depth + 1);
 
-  String valueStr(value) {
-    if (value is String) {
-      return "'$value'";
-    }
-    return '$value';
-  }
-
   Never fail(String message) {
     test_package.fail(_describe() + '\n' + _indent + message);
   }
@@ -37,4 +30,16 @@
       return _describe() + '\n' + _indent + describe(value);
     });
   }
+
+  String valueStr(value) {
+    if (value is String) {
+      return "'$value'";
+    }
+    return '$value';
+  }
+
+  /// Use this if multiple checks are required on the value.
+  void which(void Function(CheckTarget<T> e) checker) {
+    checker(this);
+  }
 }
diff --git a/pkg/analyzer_utilities/lib/check/nullability.dart b/pkg/analyzer_utilities/lib/check/nullability.dart
new file mode 100644
index 0000000..ef1860e
--- /dev/null
+++ b/pkg/analyzer_utilities/lib/check/nullability.dart
@@ -0,0 +1,21 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analyzer_utilities/check/check.dart';
+
+extension NullabilityExtension<T> on CheckTarget<T?> {
+  CheckTarget<T> get isNotNull {
+    final value = this.value;
+    if (value == null) {
+      fail('is null');
+    }
+    return nest(value, (value) => 'is not null');
+  }
+
+  void get isNull {
+    if (value != null) {
+      fail('is not null');
+    }
+  }
+}
diff --git a/pkg/analyzer_utilities/lib/check/string.dart b/pkg/analyzer_utilities/lib/check/string.dart
index 3d80003..75278b8 100644
--- a/pkg/analyzer_utilities/lib/check/string.dart
+++ b/pkg/analyzer_utilities/lib/check/string.dart
@@ -12,12 +12,6 @@
     }
   }
 
-  void startsWith(Pattern other) {
-    if (!value.startsWith(other)) {
-      fail('does not start with ${valueStr(other)}');
-    }
-  }
-
   @UseResult.unless(parameterDefined: 'expected')
   CheckTarget<int> hasLength([int? expected]) {
     var actual = value.length;
@@ -28,4 +22,10 @@
 
     return nest(actual, (length) => 'has length $length');
   }
+
+  void startsWith(Pattern other) {
+    if (!value.startsWith(other)) {
+      fail('does not start with ${valueStr(other)}');
+    }
+  }
 }
diff --git a/pkg/analyzer_utilities/lib/tools.dart b/pkg/analyzer_utilities/lib/tools.dart
index a072d85..00724c7 100644
--- a/pkg/analyzer_utilities/lib/tools.dart
+++ b/pkg/analyzer_utilities/lib/tools.dart
@@ -283,14 +283,8 @@
     if (generateNeeded) {
       print('Please regenerate using:');
       var executable = Platform.executable;
-      var packageRoot = '';
-      // ignore: deprecated_member_use
-      if (Platform.packageRoot != null) {
-        // ignore: deprecated_member_use
-        packageRoot = ' --package-root=${Platform.packageRoot}';
-      }
       var generateScript = normalize(joinAll(posix.split(generatorPath)));
-      print('  $executable$packageRoot $generateScript ${args.join(" ")}');
+      print('  $executable $generateScript ${args.join(" ")}');
       fail('Error codes need to be generated');
     } else {
       print('All generated files up to date.');
diff --git a/pkg/analyzer_utilities/test/check/check_test.dart b/pkg/analyzer_utilities/test/check/check_test.dart
index cc52f80..907438f 100644
--- a/pkg/analyzer_utilities/test/check/check_test.dart
+++ b/pkg/analyzer_utilities/test/check/check_test.dart
@@ -97,6 +97,18 @@
         _fails(() => check(<int>{}).isNotEmpty);
       });
     });
+    group('nullability', () {
+      const int? notNullable = 0;
+      const int? nullable = null;
+      test('isNotNull', () {
+        check(notNullable).isNotNull;
+        _fails(() => check(nullable).isNotNull.isZero);
+      });
+      test('isNull', () {
+        check(nullable).isNull;
+        _fails(() => check(notNullable).isNull);
+      });
+    });
     group('String', () {
       test('contains', () {
         check('abc').contains('a');
@@ -153,6 +165,10 @@
         _fails(() => check('abc' as dynamic).isA<int>());
       });
     });
+    test('which', () {
+      check(0).which((e) => e.isZero);
+      _fails(() => check(1).which((e) => e.isZero));
+    });
   });
 }
 
diff --git a/pkg/compiler/analysis_options.yaml b/pkg/compiler/analysis_options.yaml
index 2ab9f2f..1645941 100644
--- a/pkg/compiler/analysis_options.yaml
+++ b/pkg/compiler/analysis_options.yaml
@@ -5,9 +5,6 @@
 analyzer:
   errors:
     todo: ignore
-    # Allow cross-package deprecated calls
-    # TODO(srawlins): clean these up and remove this "ignore."
-    deprecated_member_use: ignore
     # Allow deprecated calls from within the same package
     deprecated_member_use_from_same_package: ignore
 
diff --git a/pkg/compiler/lib/src/common_elements.dart b/pkg/compiler/lib/src/common_elements.dart
index d4e63fb..cead301 100644
--- a/pkg/compiler/lib/src/common_elements.dart
+++ b/pkg/compiler/lib/src/common_elements.dart
@@ -302,6 +302,8 @@
 
   InterfaceType get jsJavaScriptFunctionType;
 
+  ClassEntity get jsLegacyJavaScriptObjectClass;
+
   ClassEntity get jsJavaScriptObjectClass;
 
   ClassEntity get jsIndexableClass;
@@ -1348,6 +1350,12 @@
   InterfaceType get jsJavaScriptFunctionType =>
       _getRawType(jsJavaScriptFunctionClass);
 
+  ClassEntity _jsLegacyJavaScriptObjectClass;
+  @override
+  ClassEntity get jsLegacyJavaScriptObjectClass =>
+      _jsLegacyJavaScriptObjectClass ??=
+          _findInterceptorsClass('LegacyJavaScriptObject');
+
   ClassEntity _jsJavaScriptObjectClass;
   @override
   ClassEntity get jsJavaScriptObjectClass =>
@@ -2166,7 +2174,7 @@
   ClassEntity getDefaultSuperclass(
       ClassEntity cls, NativeBasicData nativeBasicData) {
     if (nativeBasicData.isJsInteropClass(cls)) {
-      return jsJavaScriptObjectClass;
+      return jsLegacyJavaScriptObjectClass;
     }
     // Native classes inherit from Interceptor.
     return nativeBasicData.isNativeClass(cls)
diff --git a/pkg/compiler/lib/src/compiler.dart b/pkg/compiler/lib/src/compiler.dart
index 146e093..dad3d720 100644
--- a/pkg/compiler/lib/src/compiler.dart
+++ b/pkg/compiler/lib/src/compiler.dart
@@ -344,8 +344,8 @@
         }
         frontendStrategy.registerModuleData(data);
 
-        // After we've deserialized modular data, we set and verify the main
-        // method as well as trim the component of any unnecessary dependencies.
+        // After we've deserialized modular data, we trim the component of any
+        // unnecessary dependencies.
         // Note: It is critical we wait to trim the dill until after we've
         // deserialized modular data because some of this data may reference
         // 'trimmed' elements.
@@ -354,14 +354,7 @@
             dumpUnusedLibraries(result);
           }
           if (options.entryUri != null) {
-            result.setMainAndTrimComponent(options.entryUri);
-          }
-          if (result.component.mainMethod == null) {
-            // TODO(sigmund): move this so that we use the same error template
-            // from the CFE.
-            _reporter.reportError(_reporter.createMessage(NO_LOCATION_SPANNABLE,
-                MessageKind.GENERIC, {'text': "No 'main' method found."}));
-            return;
+            result.trimComponent();
           }
         }
         if (options.cfeOnly) {
diff --git a/pkg/compiler/lib/src/io/position_information.dart b/pkg/compiler/lib/src/io/position_information.dart
index 1fa1dc4..8d2c4b9 100644
--- a/pkg/compiler/lib/src/io/position_information.dart
+++ b/pkg/compiler/lib/src/io/position_information.dart
@@ -364,6 +364,9 @@
       reader.getSourceInformation(node);
 
   @override
+  SourceInformation visitComment(js.Comment node) => null;
+
+  @override
   SourceInformation visitExpressionStatement(js.ExpressionStatement node) {
     SourceInformation sourceInformation = reader.getSourceInformation(node);
     if (sourceInformation != null) {
@@ -864,7 +867,7 @@
 
 /// Visitor that computes the [js.Node]s the are part of the JavaScript
 /// steppable execution and thus needs source mapping locations.
-class JavaScriptTracer extends js.BaseVisitor {
+class JavaScriptTracer extends js.BaseVisitorVoid {
   final CodePositionMap codePositions;
   final SourceInformationReader reader;
   final List<TraceListener> listeners;
diff --git a/pkg/compiler/lib/src/js/js.dart b/pkg/compiler/lib/src/js/js.dart
index c8f5a30..6a8fecd 100644
--- a/pkg/compiler/lib/src/js/js.dart
+++ b/pkg/compiler/lib/src/js/js.dart
@@ -101,9 +101,9 @@
 }
 
 /// Implements reference counting for instances of [ReferenceCountedAstNode]
-class TokenCounter extends BaseVisitor {
+class TokenCounter extends BaseVisitorVoid {
   @override
-  visitNode(Node node) {
+  void visitNode(Node node) {
     if (node is AstContainer) {
       for (Node element in node.containedNodes) {
         element.accept(this);
diff --git a/pkg/compiler/lib/src/js/js_debug.dart b/pkg/compiler/lib/src/js/js_debug.dart
index 11b3b83..19d6600 100644
--- a/pkg/compiler/lib/src/js/js_debug.dart
+++ b/pkg/compiler/lib/src/js/js_debug.dart
@@ -23,7 +23,7 @@
 
 /// Visitor that creates an XML-like representation of the structure of a
 /// JavaScript [Node].
-class DebugPrinter extends BaseVisitor with Indentation, Tagging<Node> {
+class DebugPrinter extends BaseVisitorVoid with Indentation, Tagging<Node> {
   @override
   StringBuffer sb = StringBuffer();
 
diff --git a/pkg/compiler/lib/src/js/placeholder_safety.dart b/pkg/compiler/lib/src/js/placeholder_safety.dart
index dc5d7a7..9f14b58 100644
--- a/pkg/compiler/lib/src/js/placeholder_safety.dart
+++ b/pkg/compiler/lib/src/js/placeholder_safety.dart
@@ -63,7 +63,12 @@
   @override
   int visitNode(js.Node node) {
     safe = false;
-    super.visitNode(node);
+    node.visitChildren(this);
+    return UNKNOWN_VALUE;
+  }
+
+  @override
+  int visitComment(js.Comment node) {
     return UNKNOWN_VALUE;
   }
 
diff --git a/pkg/compiler/lib/src/js/rewrite_async.dart b/pkg/compiler/lib/src/js/rewrite_async.dart
index 8a48496..803221c 100644
--- a/pkg/compiler/lib/src/js/rewrite_async.dart
+++ b/pkg/compiler/lib/src/js/rewrite_async.dart
@@ -2465,6 +2465,11 @@
   }
 
   @override
+  bool visitNode(js.Node node) {
+    throw StateError('Node type ${node.runtimeType} not handled: $node');
+  }
+
+  @override
   bool visitAccess(js.PropertyAccess node) {
     bool receiver = visit(node.receiver);
     bool selector = visit(node.selector);
diff --git a/pkg/compiler/lib/src/js_backend/backend_impact.dart b/pkg/compiler/lib/src/js_backend/backend_impact.dart
index f82c523..170924c 100644
--- a/pkg/compiler/lib/src/js_backend/backend_impact.dart
+++ b/pkg/compiler/lib/src/js_backend/backend_impact.dart
@@ -520,6 +520,7 @@
         ],
         instantiatedClasses: [
           _commonElements.jsJavaScriptObjectClass,
+          _commonElements.jsLegacyJavaScriptObjectClass,
           _commonElements.jsPlainJavaScriptObjectClass,
           _commonElements.jsJavaScriptFunctionClass
         ],
@@ -607,6 +608,7 @@
     ], globalClasses: [
       _commonElements.jsInterceptorClass,
       _commonElements.jsJavaScriptObjectClass,
+      _commonElements.jsLegacyJavaScriptObjectClass,
       _commonElements.jsPlainJavaScriptObjectClass,
       _commonElements.jsJavaScriptFunctionClass
     ]);
diff --git a/pkg/compiler/lib/src/js_backend/codegen_listener.dart b/pkg/compiler/lib/src/js_backend/codegen_listener.dart
index fe62f76..4a93bce 100644
--- a/pkg/compiler/lib/src/js_backend/codegen_listener.dart
+++ b/pkg/compiler/lib/src/js_backend/codegen_listener.dart
@@ -291,6 +291,8 @@
       registerInstantiation(_commonElements.jsNumberClass);
     } else if (cls == _commonElements.jsJavaScriptObjectClass) {
       registerInstantiation(_commonElements.jsJavaScriptObjectClass);
+    } else if (cls == _commonElements.jsLegacyJavaScriptObjectClass) {
+      registerInstantiation(_commonElements.jsLegacyJavaScriptObjectClass);
     } else if (cls == _commonElements.jsPlainJavaScriptObjectClass) {
       registerInstantiation(_commonElements.jsPlainJavaScriptObjectClass);
     } else if (cls == _commonElements.jsUnknownJavaScriptObjectClass) {
diff --git a/pkg/compiler/lib/src/js_backend/deferred_holder_expression.dart b/pkg/compiler/lib/src/js_backend/deferred_holder_expression.dart
index 8b46bb4..a9aa753 100644
--- a/pkg/compiler/lib/src/js_backend/deferred_holder_expression.dart
+++ b/pkg/compiler/lib/src/js_backend/deferred_holder_expression.dart
@@ -823,7 +823,7 @@
 ///
 /// The state is kept in the finalizer so that this scan could be extended to
 /// look for other deferred expressions in one pass.
-class _DeferredHolderExpressionCollectorVisitor extends js.BaseVisitor<void> {
+class _DeferredHolderExpressionCollectorVisitor extends js.BaseVisitorVoid {
   String resourceName;
   final DeferredHolderExpressionFinalizer _finalizer;
 
@@ -882,307 +882,3 @@
   final js.Statement statement;
   HolderInitCode(this.allHolders, this.activeHolders, this.statement);
 }
-
-/// All of the code below this point is legacy code.
-
-/// [DeferredHolderExpressionFinalizerImpl] finalizes
-/// [DeferredHolderExpression]s, [DeferredHolderParameter]s,
-/// [DeferredHolderResource]s, [DeferredHolderResourceExpression]s.
-class LegacyDeferredHolderExpressionFinalizerImpl
-    implements DeferredHolderExpressionFinalizer {
-  _DeferredHolderExpressionCollectorVisitor _visitor;
-  final List<DeferredHolderExpression> holderReferences = [];
-  final List<DeferredHolderParameter> holderParameters = [];
-  final List<DeferredHolderResource> holderResources = [];
-  final Set<String> _uniqueHolders = {};
-  final List<String> _holders = [];
-  final Map<Entity, String> _entityMap = {};
-  final JCommonElements _commonElements;
-
-  LegacyDeferredHolderExpressionFinalizerImpl(this._commonElements) {
-    _visitor = _DeferredHolderExpressionCollectorVisitor(this);
-  }
-
-  @override
-  void addCode(String resourceName, js.Node code) {
-    _visitor.setResourceNameAndVisit(resourceName, code);
-  }
-
-  final List<String> userGlobalObjects =
-      List.from(Namer.reservedGlobalObjectNames)
-        ..remove('C')
-        ..remove('H')
-        ..remove('J')
-        ..remove('P')
-        ..remove('W');
-
-  /// Returns the [reservedGlobalObjectNames] for [library].
-  String globalObjectForLibrary(LibraryEntity library) {
-    if (library == _commonElements.interceptorsLibrary) return 'J';
-    Uri uri = library.canonicalUri;
-    if (uri.scheme == 'dart') {
-      if (uri.path == 'html') return 'W';
-      if (uri.path.startsWith('_')) return 'H';
-      return 'P';
-    }
-    return userGlobalObjects[library.name.hashCode % userGlobalObjects.length];
-  }
-
-  /// Returns true if [element] is stored in the static state holder
-  /// ([staticStateHolder]).  We intend to store only mutable static state
-  /// there, whereas constants are stored in 'C'. Functions, accessors,
-  /// classes, etc. are stored in one of the other objects in
-  /// [reservedGlobalObjectNames].
-  bool _isPropertyOfStaticStateHolder(MemberEntity element) {
-    // TODO(ahe): Make sure this method's documentation is always true and
-    // remove the word "intend".
-    return element.isField;
-  }
-
-  String globalObjectForMember(MemberEntity entity) {
-    if (_isPropertyOfStaticStateHolder(entity)) {
-      return globalObjectForStaticState();
-    } else {
-      return globalObjectForLibrary(entity.library);
-    }
-  }
-
-  String globalObjectForClass(ClassEntity entity) {
-    return globalObjectForLibrary(entity.library);
-  }
-
-  String globalObjectForInterceptors() => 'J';
-
-  String globalObjectForStaticState() => r'$';
-
-  String globalObjectForConstants() => 'C';
-
-  String globalObjectForEntity(Entity entity) {
-    if (entity is MemberEntity) {
-      return globalObjectForMember(entity);
-    } else if (entity is ClassEntity) {
-      return globalObjectForLibrary(entity.library);
-    } else {
-      assert(entity is LibraryEntity);
-      return globalObjectForLibrary(entity);
-    }
-  }
-
-  /// Registers an [Entity] with a specific [holder].
-  void registerHolderUse(String holder, Object data) {
-    if (_uniqueHolders.add(holder)) _holders.add(holder);
-    if (data != null && data is Entity) {
-      assert(!_entityMap.containsKey(data) || _entityMap[data] == holder);
-      _entityMap[data] = holder;
-    }
-  }
-
-  /// Returns a global object for a given [Object] based on the
-  /// [DeferredHolderExpressionKind].
-  String kindToHolder(DeferredHolderExpressionKind kind, Object data) {
-    switch (kind) {
-      case DeferredHolderExpressionKind.globalObjectForInterceptors:
-        return globalObjectForInterceptors();
-      case DeferredHolderExpressionKind.globalObjectForClass:
-        return globalObjectForClass(data);
-      case DeferredHolderExpressionKind.globalObjectForMember:
-        return globalObjectForMember(data);
-      case DeferredHolderExpressionKind.globalObjectForConstant:
-        return globalObjectForConstants();
-      case DeferredHolderExpressionKind.globalObjectForStaticState:
-        return globalObjectForStaticState();
-    }
-    throw UnsupportedError("Unreachable");
-  }
-
-  /// Finalizes [DeferredHolderExpression]s [DeferredHolderParameter]s.
-  void finalizeReferences() {
-    // Finalize [DeferredHolderExpression]s and registers holder usage.
-    for (var reference in holderReferences) {
-      if (reference.isFinalized) continue;
-      Object data = reference.data;
-      String holder = kindToHolder(reference.kind, data);
-      js.Expression value = js.VariableUse(holder);
-      registerHolderUse(holder, data);
-      reference.value =
-          value.withSourceInformation(reference.sourceInformation);
-    }
-
-    // Finalize [DeferredHolderParameter]s.
-    for (var parameter in holderParameters) {
-      if (parameter.isFinalized) continue;
-      parameter.name = globalObjectForStaticState();
-    }
-  }
-
-  /// Registers all of the holders used by a given [DeferredHolderResource].
-  void registerHolders(DeferredHolderResource resource) {
-    for (var entity in resource.holderCode.keys) {
-      var holder = globalObjectForEntity(entity);
-      registerHolderUse(holder, entity);
-    }
-  }
-
-  /// Returns a [List<String>] containing all of the holders except the static
-  /// state holder.
-  List<String> get nonStaticStateHolders {
-    return _holders
-        .where((holder) => holder != globalObjectForStaticState())
-        .toList(growable: false);
-  }
-
-  /// Generates code to declare holders.
-  LegacyHolderCode declareHolders(DeferredHolderResource resource) {
-    // Collect all holders except the static state holder. Then, create a map of
-    // holder to list of properties which are associated with that holder, but
-    // only with respect to a given [DeferredHolderResource]. Each fragment will
-    // have its own [DeferredHolderResource] and associated code.
-    Map<String, List<js.Property>> codePerHolder = {};
-    final holders = nonStaticStateHolders;
-    for (var holder in holders) {
-      codePerHolder[holder] = [];
-    }
-
-    final holderCode = resource.holderCode;
-    holderCode.forEach((entity, properties) {
-      assert(_entityMap.containsKey(entity));
-      var holder = _entityMap[entity];
-      assert(codePerHolder.containsKey(holder));
-      codePerHolder[holder].addAll(properties);
-    });
-
-    // Create holder initialization code based on the [codePerHolder]. If there
-    // are no properties associated with a given holder in this specific
-    // [DeferredHolderResource] then it will be omitted. However, in some cases,
-    // i.e. the main output unit, we still want to declare the holder with an
-    // empty object literal which will be filled in later by another
-    // [DeferredHolderResource], i.e. in a specific deferred fragment.
-    // The generated code looks like this:
-    //
-    //    {
-    //      var H = {...}, ..., G = {...};
-    //      var holders = [ H, ..., G ]; // Main unit only.
-    //    }
-
-    List<String> activeHolders = [];
-    List<js.VariableInitialization> holderInitializations = [];
-    for (var holder in holders) {
-      List<js.Property> properties = codePerHolder[holder];
-      if (properties.isEmpty) {
-        holderInitializations.add(js.VariableInitialization(
-            js.VariableDeclaration(holder, allowRename: false),
-            resource.isMainFragment ? js.ObjectInitializer(properties) : null));
-      } else {
-        activeHolders.add(holder);
-        holderInitializations.add(js.VariableInitialization(
-            js.VariableDeclaration(holder, allowRename: false),
-            js.ObjectInitializer(properties)));
-      }
-    }
-
-    List<js.Statement> statements = [];
-    statements.add(js.ExpressionStatement(js.VariableDeclarationList(
-        holderInitializations,
-        indentSplits: false)));
-    if (resource.isMainFragment) {
-      statements.add(js.js.statement(
-          'var holders = #',
-          js.ArrayInitializer(holders
-              .map((holder) => js.VariableUse(holder))
-              .toList(growable: false))));
-    }
-    return LegacyHolderCode(activeHolders, statements);
-  }
-
-  /// Finalizes [resource] to code that updates holders. [resource] must be in
-  /// the AST of a deferred fragment.
-  void updateHolders(DeferredHolderResource resource) {
-    // Declare holders.
-    final holderCode = declareHolders(resource);
-
-    // Set names if necessary on deferred holders list.
-    js.Expression deferredHoldersList = js.ArrayInitializer(holderCode
-        .activeHolders
-        .map((holder) => js.js("#", holder))
-        .toList(growable: false));
-    js.Statement setNames = js.js.statement(
-        'hunkHelpers.setFunctionNamesIfNecessary(#deferredHoldersList)',
-        {'deferredHoldersList': deferredHoldersList});
-
-    // Update holder assignments.
-    final holders = nonStaticStateHolders;
-    List<js.Statement> updateHolderAssignments = [setNames];
-    for (int i = 0; i < holders.length; i++) {
-      var holder = holders[i];
-      if (holderCode.activeHolders.contains(holder)) {
-        updateHolderAssignments.add(js.js.statement(
-            '#holder = hunkHelpers.updateHolder(holdersList[#index], #holder)',
-            {'index': js.number(i), 'holder': js.VariableUse(holder)}));
-      } else {
-        // TODO(sra): Change declaration followed by assignments to declarations
-        // with initialization.
-        updateHolderAssignments.add(js.js.statement(
-            '#holder = holdersList[#index]',
-            {'index': js.number(i), 'holder': js.VariableUse(holder)}));
-      }
-    }
-
-    // Create a single block of all statements.
-    List<js.Statement> statements = holderCode.statements
-        .followedBy(updateHolderAssignments)
-        .toList(growable: false);
-    resource.statement = js.Block(statements);
-  }
-
-  /// Allocates all [DeferredHolderResource]s and
-  /// [DeferredHolderResourceExpression]s.
-  void allocateResources() {
-    // First ensure all holders used in all [DeferredHolderResource]s have been
-    // allocated.
-    for (var resource in holderResources) {
-      registerHolders(resource);
-    }
-    _holders.sort();
-
-    // Next finalize all [DeferredHolderResource]s.
-    for (var resource in holderResources) {
-      switch (resource.kind) {
-        case DeferredHolderResourceKind.mainFragment:
-          var holderCode = declareHolders(resource);
-          resource.statement = js.Block(holderCode.statements);
-          break;
-        case DeferredHolderResourceKind.deferredFragment:
-          updateHolders(resource);
-          break;
-      }
-    }
-  }
-
-  @override
-  void finalize() {
-    finalizeReferences();
-    allocateResources();
-  }
-
-  @override
-  void registerDeferredHolderExpression(
-      String resourceName, DeferredHolderExpression node) {
-    holderReferences.add(node);
-  }
-
-  @override
-  void registerDeferredHolderResource(DeferredHolderResource node) {
-    holderResources.add(node);
-  }
-
-  @override
-  void registerDeferredHolderParameter(DeferredHolderParameter node) {
-    holderParameters.add(node);
-  }
-}
-
-class LegacyHolderCode {
-  final List<String> activeHolders;
-  final List<js.Statement> statements;
-  LegacyHolderCode(this.activeHolders, this.statements);
-}
diff --git a/pkg/compiler/lib/src/js_backend/resolution_listener.dart b/pkg/compiler/lib/src/js_backend/resolution_listener.dart
index 02fc83a..0b220af 100644
--- a/pkg/compiler/lib/src/js_backend/resolution_listener.dart
+++ b/pkg/compiler/lib/src/js_backend/resolution_listener.dart
@@ -394,6 +394,9 @@
       _addInterceptors(_commonElements.jsNumberClass, impactBuilder);
     } else if (cls == _commonElements.jsJavaScriptObjectClass) {
       _addInterceptors(_commonElements.jsJavaScriptObjectClass, impactBuilder);
+    } else if (cls == _commonElements.jsLegacyJavaScriptObjectClass) {
+      _addInterceptors(
+          _commonElements.jsLegacyJavaScriptObjectClass, impactBuilder);
     } else if (cls == _commonElements.jsPlainJavaScriptObjectClass) {
       _addInterceptors(
           _commonElements.jsPlainJavaScriptObjectClass, impactBuilder);
diff --git a/pkg/compiler/lib/src/js_backend/string_reference.dart b/pkg/compiler/lib/src/js_backend/string_reference.dart
index 69d1a2d..19aba0e 100644
--- a/pkg/compiler/lib/src/js_backend/string_reference.dart
+++ b/pkg/compiler/lib/src/js_backend/string_reference.dart
@@ -422,7 +422,7 @@
 /// The state is kept in the finalizer so that this scan could be extended to
 /// look for other deferred expressions in one pass.
 // TODO(sra): Merge with TypeReferenceCollectorVisitor.
-class _StringReferenceCollectorVisitor extends js.BaseVisitor<void> {
+class _StringReferenceCollectorVisitor extends js.BaseVisitorVoid {
   final StringReferenceFinalizerImpl _finalizer;
 
   _StringReferenceCollectorVisitor(this._finalizer);
diff --git a/pkg/compiler/lib/src/js_backend/type_reference.dart b/pkg/compiler/lib/src/js_backend/type_reference.dart
index 7bfc470..e135ab8 100644
--- a/pkg/compiler/lib/src/js_backend/type_reference.dart
+++ b/pkg/compiler/lib/src/js_backend/type_reference.dart
@@ -533,7 +533,7 @@
 ///
 /// The state is kept in the finalizer so that this scan could be extended to
 /// look for other deferred expressions in one pass.
-class _TypeReferenceCollectorVisitor extends js.BaseVisitor<void> {
+class _TypeReferenceCollectorVisitor extends js.BaseVisitorVoid {
   final TypeReferenceFinalizerImpl _finalizer;
 
   _TypeReferenceCollectorVisitor(this._finalizer);
diff --git a/pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart b/pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart
index c9130bd..69dc9f4 100644
--- a/pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart
+++ b/pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart
@@ -164,7 +164,7 @@
   Set<Class> _unneededNativeClasses;
 
   ClassEntity get _jsInteropInterceptor =>
-      _commonElements.jsJavaScriptObjectClass;
+      _commonElements.jsLegacyJavaScriptObjectClass;
   final List<StubMethod> _jsInteropIsChecks = [];
   final Set<TypeCheck> _jsInteropTypeChecks = {};
 
diff --git a/pkg/compiler/lib/src/js_emitter/startup_emitter/fragment_emitter.dart b/pkg/compiler/lib/src/js_emitter/startup_emitter/fragment_emitter.dart
index cd26c6b..e07ef90 100644
--- a/pkg/compiler/lib/src/js_emitter/startup_emitter/fragment_emitter.dart
+++ b/pkg/compiler/lib/src/js_emitter/startup_emitter/fragment_emitter.dart
@@ -640,10 +640,8 @@
       this._nativeEmitter,
       this._closedWorld,
       this._codegenWorld)
-      : _holderFinalizer = _options.features.newHolders.isEnabled
-            ? DeferredHolderExpressionFinalizerImpl(_closedWorld.commonElements)
-            : LegacyDeferredHolderExpressionFinalizerImpl(
-                _closedWorld.commonElements) {
+      : _holderFinalizer =
+            DeferredHolderExpressionFinalizerImpl(_closedWorld.commonElements) {
     _recipeEncoder = RecipeEncoderImpl(
         _closedWorld,
         _options.disableRtiOptimization
@@ -1942,7 +1940,8 @@
   js.Block emitTypeRules(Fragment fragment) {
     List<js.Statement> statements = [];
 
-    ClassEntity jsObjectClass = _commonElements.jsJavaScriptObjectClass;
+    ClassEntity legacyJsObjectClass =
+        _commonElements.jsLegacyJavaScriptObjectClass;
 
     Map<ClassTypeData, List<ClassTypeData>> nativeRedirections =
         _nativeEmitter.typeRedirections;
@@ -1960,10 +1959,11 @@
         erasedTypes[element] = targetType.typeArguments.length;
       }
 
-      bool isInterop = _classHierarchy.isSubclassOf(element, jsObjectClass);
+      bool isInterop =
+          _classHierarchy.isSubclassOf(element, legacyJsObjectClass);
 
-      if (isInterop && element != jsObjectClass) {
-        ruleset.addRedirection(element, jsObjectClass);
+      if (isInterop && element != legacyJsObjectClass) {
+        ruleset.addRedirection(element, legacyJsObjectClass);
       } else {
         Iterable<TypeCheck> checks = typeData.classChecks?.checks ?? const [];
         Iterable<InterfaceType> supertypes = isInterop
diff --git a/pkg/compiler/lib/src/js_emitter/startup_emitter/model_emitter.dart b/pkg/compiler/lib/src/js_emitter/startup_emitter/model_emitter.dart
index de9ddca..ea27263 100644
--- a/pkg/compiler/lib/src/js_emitter/startup_emitter/model_emitter.dart
+++ b/pkg/compiler/lib/src/js_emitter/startup_emitter/model_emitter.dart
@@ -64,7 +64,6 @@
         DeferredHolderParameter,
         DeferredHolderResource,
         DeferredHolderResourceKind,
-        LegacyDeferredHolderExpressionFinalizerImpl,
         mainResourceName;
 import '../../js_backend/type_reference.dart'
     show
diff --git a/pkg/compiler/lib/src/js_model/js_world.dart b/pkg/compiler/lib/src/js_model/js_world.dart
index d379248..17fd5d2 100644
--- a/pkg/compiler/lib/src/js_model/js_world.dart
+++ b/pkg/compiler/lib/src/js_model/js_world.dart
@@ -246,7 +246,7 @@
   ClassEntity getLubOfInstantiatedSubclasses(ClassEntity cls) {
     if (nativeData.isJsInteropClass(cls)) {
       return getLubOfInstantiatedSubclasses(
-          commonElements.jsJavaScriptObjectClass);
+          commonElements.jsLegacyJavaScriptObjectClass);
     }
     ClassHierarchyNode hierarchy = classHierarchy.getClassHierarchyNode(cls);
     return hierarchy?.getLubOfInstantiatedSubclasses();
@@ -256,7 +256,7 @@
   ClassEntity getLubOfInstantiatedSubtypes(ClassEntity cls) {
     if (nativeData.isJsInteropClass(cls)) {
       return getLubOfInstantiatedSubtypes(
-          commonElements.jsJavaScriptObjectClass);
+          commonElements.jsLegacyJavaScriptObjectClass);
     }
     ClassSet classSet = classHierarchy.getClassSet(cls);
     return classSet?.getLubOfInstantiatedSubtypes();
diff --git a/pkg/compiler/lib/src/kernel/dart2js_target.dart b/pkg/compiler/lib/src/kernel/dart2js_target.dart
index d8985b7..01f42be 100644
--- a/pkg/compiler/lib/src/kernel/dart2js_target.dart
+++ b/pkg/compiler/lib/src/kernel/dart2js_target.dart
@@ -12,6 +12,7 @@
     show Message, LocatedMessage;
 import 'package:_js_interop_checks/js_interop_checks.dart';
 import 'package:_js_interop_checks/src/transformations/js_util_optimizer.dart';
+import 'package:_js_interop_checks/src/transformations/static_interop_class_eraser.dart';
 import 'package:kernel/ast.dart' as ir;
 import 'package:kernel/class_hierarchy.dart';
 import 'package:kernel/core_types.dart';
@@ -142,6 +143,7 @@
       ChangedStructureNotifier? changedStructureNotifier}) {
     var nativeClasses = JsInteropChecks.getNativeClasses(component);
     var jsUtilOptimizer = JsUtilOptimizer(coreTypes, hierarchy);
+    var staticInteropClassEraser = StaticInteropClassEraser(coreTypes);
     for (var library in libraries) {
       JsInteropChecks(
               coreTypes,
@@ -151,6 +153,7 @@
       // TODO (rileyporter): Merge js_util optimizations with other lowerings
       // in the single pass in `transformations/lowering.dart`.
       jsUtilOptimizer.visitLibrary(library);
+      staticInteropClassEraser.visitLibrary(library);
     }
     lowering.transformLibraries(libraries, coreTypes, hierarchy, options);
     logger?.call("Lowering transformations performed");
diff --git a/pkg/compiler/lib/src/kernel/element_map_impl.dart b/pkg/compiler/lib/src/kernel/element_map_impl.dart
index 827bf20..f82c5ef 100644
--- a/pkg/compiler/lib/src/kernel/element_map_impl.dart
+++ b/pkg/compiler/lib/src/kernel/element_map_impl.dart
@@ -468,7 +468,7 @@
     }
 
     /// This path is needed for synthetically injected superclasses like
-    /// `Interceptor` and `JavaScriptObject`.
+    /// `Interceptor` and `LegacyJavaScriptObject`.
     KClassEnv env = classes.getEnv(superClass);
     ConstructorEntity constructor = env.lookupConstructor(this, target.name);
     if (constructor != null) {
diff --git a/pkg/compiler/lib/src/kernel/loader.dart b/pkg/compiler/lib/src/kernel/loader.dart
index dbefdbb..cdab490 100644
--- a/pkg/compiler/lib/src/kernel/loader.dart
+++ b/pkg/compiler/lib/src/kernel/loader.dart
@@ -52,6 +52,37 @@
   @override
   String get name => 'kernel loader';
 
+  static Library _findEntryLibrary(Component component, Uri entryUri) {
+    var entryLibrary = component.libraries
+        .firstWhere((l) => l.fileUri == entryUri, orElse: () => null);
+    if (entryLibrary == null) {
+      throw ArgumentError('Entry uri $entryUri not found in dill.');
+    }
+    return entryLibrary;
+  }
+
+  static ir.Reference _findMainMethod(Library entryLibrary) {
+    var mainMethod = entryLibrary.procedures
+        .firstWhere((p) => p.name.text == 'main', orElse: () => null);
+
+    // In some cases, a main method is defined in another file, and then
+    // exported. In these cases, we search for the main method in
+    // [additionalExports].
+    ir.Reference mainMethodReference;
+    if (mainMethod == null) {
+      mainMethodReference = entryLibrary.additionalExports.firstWhere(
+          (p) => p.canonicalName.name == 'main',
+          orElse: () => null);
+    } else {
+      mainMethodReference = mainMethod.reference;
+    }
+    if (mainMethodReference == null) {
+      throw ArgumentError(
+          'Entry uri ${entryLibrary.fileUri} has no main method.');
+    }
+    return mainMethodReference;
+  }
+
   /// Loads an entire Kernel [Component] from a file on disk.
   Future<KernelResult> load() {
     return measure(() async {
@@ -65,6 +96,9 @@
         return "${targetName}_platform$unsoundMarker.dill";
       }
 
+      // If we are passed an [entryUri] and building from dill, then we lookup
+      // the [entryLibrary] in the built component.
+      Library entryLibrary;
       var resolvedUri = _options.compilationTarget;
       ir.Component component;
       List<Uri> moduleLibraries = const [];
@@ -128,6 +162,12 @@
             await read(dependency);
           }
         }
+
+        if (_options.entryUri != null) {
+          entryLibrary = _findEntryLibrary(component, _options.entryUri);
+          var mainMethod = _findMainMethod(entryLibrary);
+          component.setMainMethodAndMode(mainMethod, true, component.mode);
+        }
       } else {
         bool verbose = false;
         Target target =
@@ -186,15 +226,31 @@
         component = ir.Component();
         BinaryBuilder(data).readComponent(component);
       }
-      return _toResult(component, moduleLibraries);
+      return _toResult(entryLibrary, component, moduleLibraries);
     });
   }
 
-  KernelResult _toResult(ir.Component component, List<Uri> moduleLibraries) {
+  KernelResult _toResult(
+      Library entryLibrary, ir.Component component, List<Uri> moduleLibraries) {
     Uri rootLibraryUri = null;
     Iterable<ir.Library> libraries = component.libraries;
-    if (!_options.modularMode && component.mainMethod != null) {
-      var root = component.mainMethod.enclosingLibrary;
+    if (!_options.modularMode) {
+      // For non-modular builds we should always have a [mainMethod] at this
+      // point.
+      if (component.mainMethod == null) {
+        // TODO(sigmund): move this so that we use the same error template
+        // from the CFE.
+        _reporter.reportError(_reporter.createMessage(NO_LOCATION_SPANNABLE,
+            MessageKind.GENERIC, {'text': "No 'main' method found."}));
+      }
+
+      // If we are building from dill and are passed an [entryUri], then we use
+      // that to find the appropriate [entryLibrary]. Otherwise, we fallback to
+      // the [enclosingLibrary] of the [mainMethod].
+      // NOTE: Under some circumstances, the [entryLibrary] exports the
+      // [mainMethod] from another library, and thus the [enclosingLibrary] of
+      // the [mainMethod] may not be the same as the [entryLibrary].
+      var root = entryLibrary ?? component.mainMethod.enclosingLibrary;
       rootLibraryUri = root.importUri;
 
       // Filter unreachable libraries: [Component] was built by linking in the
@@ -250,40 +306,7 @@
   KernelResult(this.component, this.rootLibraryUri, this.libraries,
       this.moduleLibraries);
 
-  static Library _findEntryLibrary(Component component, Uri entryUri) {
-    var entryLibrary = component.libraries
-        .firstWhere((l) => l.fileUri == entryUri, orElse: () => null);
-    if (entryLibrary == null) {
-      throw ArgumentError('Entry uri $entryUri not found in dill.');
-    }
-    return entryLibrary;
-  }
-
-  static ir.Reference _findMainMethod(Library entryLibrary) {
-    var mainMethod = entryLibrary.procedures
-        .firstWhere((p) => p.name.text == 'main', orElse: () => null);
-
-    // In some cases, a main method is defined in another file, and then
-    // exported. In these cases, we search for the main method in
-    // [additionalExports].
-    ir.Reference mainMethodReference;
-    if (mainMethod == null) {
-      mainMethodReference = entryLibrary.additionalExports.firstWhere(
-          (p) => p.canonicalName.name == 'main',
-          orElse: () => null);
-    } else {
-      mainMethodReference = mainMethod.reference;
-    }
-    if (mainMethodReference == null) {
-      throw ArgumentError(
-          'Entry uri ${entryLibrary.fileUri} has no main method.');
-    }
-    return mainMethodReference;
-  }
-
-  void setMainAndTrimComponent(Uri entryUri) {
-    var entryLibrary = _findEntryLibrary(component, entryUri);
-    var mainMethod = _findMainMethod(entryLibrary);
+  void trimComponent() {
     var irLibraryMap = <Uri, Library>{};
     var irLibraries = <Library>[];
     for (var library in component.libraries) {
@@ -292,11 +315,13 @@
     for (var library in libraries) {
       irLibraries.add(irLibraryMap[library]);
     }
+    var mainMethod = component.mainMethodName;
+    var componentMode = component.mode;
     component = ir.Component(
         libraries: irLibraries,
         uriToSource: component.uriToSource,
         nameRoot: component.root);
-    component.setMainMethodAndMode(mainMethod, true, component.mode);
+    component.setMainMethodAndMode(mainMethod, true, componentMode);
   }
 
   @override
diff --git a/pkg/compiler/lib/src/kernel/transformations/late_lowering.dart b/pkg/compiler/lib/src/kernel/transformations/late_lowering.dart
index 18b56dc..bdec099 100644
--- a/pkg/compiler/lib/src/kernel/transformations/late_lowering.dart
+++ b/pkg/compiler/lib/src/kernel/transformations/late_lowering.dart
@@ -280,13 +280,17 @@
       Name name = field.name;
       Uri fileUri = field.fileUri;
       DartType type = field.type;
+      // We need to unbind the canonical name since we reuse the reference but
+      // change the name.
+      field.fieldReference.canonicalName?.unbind();
       Field fieldCell = Field.immutable(_mangleFieldCellName(field),
           type: InterfaceType(_coreTypes.cellClass, nonNullable),
           initializer: _callCellConstructor(
               _nameLiteral(name.text, fileOffset), fileOffset),
           isFinal: true,
           isStatic: true,
-          fileUri: fileUri)
+          fileUri: fileUri,
+          fieldReference: field.fieldReference)
         ..fileOffset = fileOffset
         ..isNonNullableByDefault = true;
       StaticGet fieldCellAccess() =>
@@ -364,6 +368,8 @@
     Expression? initializer = field.initializer;
     Class enclosingClass = field.enclosingClass!;
 
+    // We need to unbind the canonical name since we reuse the reference but
+    // change the name.
     field.fieldReference.canonicalName?.unbind();
     Field backingField = Field.mutable(mangledName,
         type: type,
diff --git a/pkg/compiler/lib/src/native/behavior.dart b/pkg/compiler/lib/src/native/behavior.dart
index e81dda1..f59b9fd 100644
--- a/pkg/compiler/lib/src/native/behavior.dart
+++ b/pkg/compiler/lib/src/native/behavior.dart
@@ -820,7 +820,7 @@
         // JS interop API returns dynamic.  This means that to some degree we
         // still use the return type to decide whether to include native types,
         // even though we don't trust the type annotation.
-        ClassEntity cls = commonElements.jsJavaScriptObjectClass;
+        ClassEntity cls = commonElements.jsLegacyJavaScriptObjectClass;
         _behavior.typesInstantiated.add(elementEnvironment.getThisType(cls));
       }
     }
diff --git a/pkg/compiler/lib/src/native/enqueue.dart b/pkg/compiler/lib/src/native/enqueue.dart
index 2177dd4..26ff0d0 100644
--- a/pkg/compiler/lib/src/native/enqueue.dart
+++ b/pkg/compiler/lib/src/native/enqueue.dart
@@ -115,7 +115,7 @@
         } else if (_dartTypes.isSubtype(
             type,
             _elementEnvironment
-                .getRawType(_commonElements.jsJavaScriptObjectClass))) {
+                .getRawType(_commonElements.jsLegacyJavaScriptObjectClass))) {
           matchingClasses.add(type.element);
         }
         // TODO(johnniwinther): Improve spec string precision to handle type
diff --git a/pkg/compiler/lib/src/native/js.dart b/pkg/compiler/lib/src/native/js.dart
index 166fc6a..9c21348 100644
--- a/pkg/compiler/lib/src/native/js.dart
+++ b/pkg/compiler/lib/src/native/js.dart
@@ -6,7 +6,7 @@
 import '../universe/side_effects.dart' show SideEffects;
 import 'behavior.dart';
 
-class HasCapturedPlaceholders extends js.BaseVisitor {
+class HasCapturedPlaceholders extends js.BaseVisitorVoid {
   HasCapturedPlaceholders._();
 
   static bool check(js.Node node) {
@@ -19,21 +19,21 @@
   bool found = false;
 
   @override
-  visitFunctionExpression(js.FunctionExpression node) {
+  void visitFunctionExpression(js.FunctionExpression node) {
     ++enclosingFunctions;
     node.visitChildren(this);
     --enclosingFunctions;
   }
 
   @override
-  visitInterpolatedNode(js.InterpolatedNode node) {
+  void visitInterpolatedNode(js.InterpolatedNode node) {
     if (enclosingFunctions > 0) {
       found = true;
     }
   }
 }
 
-class SideEffectsVisitor extends js.BaseVisitor {
+class SideEffectsVisitor extends js.BaseVisitorVoid {
   final SideEffects sideEffects;
   SideEffectsVisitor(this.sideEffects);
 
@@ -167,6 +167,11 @@
   }
 
   @override
+  NativeThrowBehavior visitComment(js.Comment node) {
+    return NativeThrowBehavior.NEVER;
+  }
+
+  @override
   NativeThrowBehavior visitLiteral(js.Literal node) {
     return NativeThrowBehavior.NEVER;
   }
diff --git a/pkg/compiler/lib/src/options.dart b/pkg/compiler/lib/src/options.dart
index d78db4c..b0be710 100644
--- a/pkg/compiler/lib/src/options.dart
+++ b/pkg/compiler/lib/src/options.dart
@@ -77,12 +77,13 @@
   FeatureOption useContentSecurityPolicy = FeatureOption('csp');
 
   /// [FeatureOption]s which are shipped and cannot be toggled.
-  late final List<FeatureOption> shipped = [];
+  late final List<FeatureOption> shipped = [
+    newHolders,
+  ];
 
   /// [FeatureOption]s which default to enabled.
   late final List<FeatureOption> shipping = [
     legacyJavaScript,
-    newHolders,
     useContentSecurityPolicy
   ];
 
@@ -168,8 +169,6 @@
   }
 
   /// Location of the package configuration file.
-  ///
-  /// If not null then [packageRoot] should be null.
   Uri? packageConfig;
 
   /// List of kernel files to load.
diff --git a/pkg/compiler/lib/src/ssa/builder_kernel.dart b/pkg/compiler/lib/src/ssa/builder_kernel.dart
index 56683e5..56dc39ec 100644
--- a/pkg/compiler/lib/src/ssa/builder_kernel.dart
+++ b/pkg/compiler/lib/src/ssa/builder_kernel.dart
@@ -1074,35 +1074,18 @@
         arguments.positional[positionalIndex++].accept(this);
         builtArguments.add(pop());
       } else {
-        ConstantValue constantValue = _elementMap.getConstantValue(
-            member, parameter.initializer,
-            implicitNull: true);
-        assert(
-            constantValue != null,
-            failedAt(_elementMap.getMethod(function.parent),
-                'No constant computed for $parameter'));
-        builtArguments.add(graph.addConstant(constantValue, closedWorld));
+        builtArguments.add(_defaultValueForParameter(member, parameter));
       }
     });
+    // Evaluate named arguments in given order.
+    Map<String, HInstruction> namedArguments = _visitNamedArguments(arguments);
+    // And add them to `builtArguments` in calling-convention order.
     function.namedParameters.toList()
       ..sort(namedOrdering)
       ..forEach((ir.VariableDeclaration parameter) {
-        var correspondingNamed = arguments.named.firstWhere(
-            (named) => named.name == parameter.name,
-            orElse: () => null);
-        if (correspondingNamed != null) {
-          correspondingNamed.value.accept(this);
-          builtArguments.add(pop());
-        } else {
-          ConstantValue constantValue = _elementMap.getConstantValue(
-              member, parameter.initializer,
-              implicitNull: true);
-          assert(
-              constantValue != null,
-              failedAt(_elementMap.getMethod(function.parent),
-                  'No constant computed for $parameter'));
-          builtArguments.add(graph.addConstant(constantValue, closedWorld));
-        }
+        var argument = namedArguments[parameter.name];
+        argument ??= _defaultValueForParameter(member, parameter);
+        builtArguments.add(argument);
       });
 
     return builtArguments;
@@ -3586,7 +3569,8 @@
     }
   }
 
-  /// Extracts the list of instructions for the positional subset of arguments.
+  /// Generate instructions to evaluate the positional arguments in source
+  /// order.
   List<HInstruction> _visitPositionalArguments(ir.Arguments arguments) {
     List<HInstruction> result = [];
     for (ir.Expression argument in arguments.positional) {
@@ -3596,6 +3580,17 @@
     return result;
   }
 
+  /// Generate instructions to evaluate the named arguments in source order.
+  /// Returns a fresh map from parameter name to evaluated argument.
+  Map<String, HInstruction> _visitNamedArguments(ir.Arguments arguments) {
+    Map<String, HInstruction> values = {};
+    for (ir.NamedExpression argument in arguments.named) {
+      argument.value.accept(this);
+      values[argument.name] = pop();
+    }
+    return values;
+  }
+
   /// Builds the list of instructions for the expressions in the arguments to a
   /// dynamic target (member function).  Dynamic targets use stubs to add
   /// defaulted arguments, so (unlike static targets) we do not add the default
@@ -3606,11 +3601,7 @@
     List<HInstruction> values = _visitPositionalArguments(arguments);
 
     if (arguments.named.isNotEmpty) {
-      Map<String, HInstruction> namedValues = {};
-      for (ir.NamedExpression argument in arguments.named) {
-        argument.value.accept(this);
-        namedValues[argument.name] = pop();
-      }
+      Map<String, HInstruction> namedValues = _visitNamedArguments(arguments);
       for (String name in selector.callStructure.getOrderedNamedArguments()) {
         values.add(namedValues[name]);
       }
@@ -3638,11 +3629,7 @@
       if (function is ConstructorEntity && function.isFactoryConstructor) {
         // TODO(sra): Have a "CompiledArguments" structure to just update with
         // what values we have rather than creating a map and de-populating it.
-        Map<String, HInstruction> namedValues = {};
-        for (ir.NamedExpression argument in arguments.named) {
-          argument.value.accept(this);
-          namedValues[argument.name] = pop();
-        }
+        Map<String, HInstruction> namedValues = _visitNamedArguments(arguments);
 
         // Visit named arguments in parameter-position order, selecting provided
         // or default value.
@@ -3719,11 +3706,7 @@
     }
 
     if (parameterStructure.namedParameters.isNotEmpty) {
-      Map<String, HInstruction> namedValues = {};
-      for (ir.NamedExpression argument in arguments.named) {
-        argument.value.accept(this);
-        namedValues[argument.name] = pop();
-      }
+      Map<String, HInstruction> namedValues = _visitNamedArguments(arguments);
 
       // Visit named arguments in parameter-position order, selecting provided
       // or default value.
@@ -5083,7 +5066,7 @@
     // resulting code bloat (e.g. from `dart:html`), we unsoundly assume that
     // only JS interop types are returned.
     nativeBehavior.typesInstantiated.add(_elementEnvironment
-        .getThisType(_commonElements.jsJavaScriptObjectClass));
+        .getThisType(_commonElements.jsLegacyJavaScriptObjectClass));
 
     AbstractValue instructionType =
         _typeInferenceMap.typeFromNativeBehavior(nativeBehavior, closedWorld);
diff --git a/pkg/compiler/lib/src/universe/world_builder.dart b/pkg/compiler/lib/src/universe/world_builder.dart
index ea42f4a..9352fa8 100644
--- a/pkg/compiler/lib/src/universe/world_builder.dart
+++ b/pkg/compiler/lib/src/universe/world_builder.dart
@@ -174,7 +174,7 @@
     if (nativeBasicData.isJsInteropClass(cls)) {
       // We can not tell js-interop classes apart, so we just assume the
       // receiver could be any js-interop class.
-      cls = commonElements.jsJavaScriptObjectClass;
+      cls = commonElements.jsLegacyJavaScriptObjectClass;
       relation = ClassRelation.subtype;
     }
     return StrongModeConstraint.internal(cls, relation);
diff --git a/pkg/compiler/test/end_to_end/launch_helper.dart b/pkg/compiler/test/end_to_end/launch_helper.dart
index 7d5a2c5..f0eef27 100644
--- a/pkg/compiler/test/end_to_end/launch_helper.dart
+++ b/pkg/compiler/test/end_to_end/launch_helper.dart
@@ -6,6 +6,7 @@
 
 import 'dart:async';
 import 'dart:io';
+
 import 'package:path/path.dart' as path;
 
 List<String> dart2JsCommand(List<String> args) {
@@ -16,9 +17,7 @@
   String dart2jsPath =
       path.normalize(path.join(basePath, 'pkg/compiler/lib/src/dart2js.dart'));
   List command = <String>[];
-  if (Platform.packageRoot != null) {
-    command.add('--package-root=${Platform.packageRoot}');
-  } else if (Platform.packageConfig != null) {
+  if (Platform.packageConfig != null) {
     command.add('--packages=${Platform.packageConfig}');
   }
   command.add(dart2jsPath);
diff --git a/pkg/compiler/test/helpers/program_lookup.dart b/pkg/compiler/test/helpers/program_lookup.dart
index 12511aa..9e985f5 100644
--- a/pkg/compiler/test/helpers/program_lookup.dart
+++ b/pkg/compiler/test/helpers/program_lookup.dart
@@ -234,7 +234,7 @@
   root.accept(visitor);
 }
 
-class CallbackVisitor extends js.BaseVisitor {
+class CallbackVisitor extends js.BaseVisitorVoid {
   final void Function(js.Call) onCall;
   final void Function(js.PropertyAccess) onPropertyAccess;
   final void Function(js.Assignment) onAssignment;
@@ -244,25 +244,25 @@
       {this.onCall, this.onPropertyAccess, this.onAssignment, this.onSwitch});
 
   @override
-  visitCall(js.Call node) {
+  void visitCall(js.Call node) {
     if (onCall != null) onCall(node);
     super.visitCall(node);
   }
 
   @override
-  visitAccess(js.PropertyAccess node) {
+  void visitAccess(js.PropertyAccess node) {
     if (onPropertyAccess != null) onPropertyAccess(node);
     super.visitAccess(node);
   }
 
   @override
-  visitAssignment(js.Assignment node) {
+  void visitAssignment(js.Assignment node) {
     if (onAssignment != null) onAssignment(node);
     return super.visitAssignment(node);
   }
 
   @override
-  visitSwitch(js.Switch node) {
+  void visitSwitch(js.Switch node) {
     if (onSwitch != null) onSwitch(node);
     return super.visitSwitch(node);
   }
diff --git a/pkg/compiler/test/impact/data/jsinterop.dart b/pkg/compiler/test/impact/data/jsinterop.dart
index b39e444..0451381 100644
--- a/pkg/compiler/test/impact/data/jsinterop.dart
+++ b/pkg/compiler/test/impact/data/jsinterop.dart
@@ -27,7 +27,7 @@
 
 @JS()
 class JsInteropClass {
-  /*member: JsInteropClass.:static=[JavaScriptObject.(0)]*/
+  /*member: JsInteropClass.:static=[LegacyJavaScriptObject.(0)]*/
   external JsInteropClass();
 
   /*member: JsInteropClass.method:
@@ -50,14 +50,14 @@
 }
 
 /*member: testJsInteropClass:
- dynamic=[JavaScriptObject.method(0)],
+ dynamic=[LegacyJavaScriptObject.method(0)],
  static=[JsInteropClass.(0)]
 */
 testJsInteropClass() => new JsInteropClass().method();
 
 typedef void Callback<T>(T value);
 
-/*member: GenericClass.:static=[JavaScriptObject.(0)]*/
+/*member: GenericClass.:static=[LegacyJavaScriptObject.(0)]*/
 @JS()
 class GenericClass<T> {
   /*member: GenericClass.method:
@@ -113,7 +113,7 @@
 }
 
 /*member: testOptionalGenericFunctionTypeArgument:
- dynamic=[JavaScriptObject.method(0)],
+ dynamic=[LegacyJavaScriptObject.method(0)],
  static=[GenericClass.(0)]
 */
 testOptionalGenericFunctionTypeArgument() => new GenericClass().method();
diff --git a/pkg/compiler/test/inference/data/js_interop.dart b/pkg/compiler/test/inference/data/js_interop.dart
index 994a675..d436c62 100644
--- a/pkg/compiler/test/inference/data/js_interop.dart
+++ b/pkg/compiler/test/inference/data/js_interop.dart
@@ -23,7 +23,7 @@
       {/*[exact=JSUInt31]*/ a, /*Value([exact=JSString], value: "")*/ b});
 }
 
-/*member: anonymousClass:[null|subclass=JavaScriptObject]*/
+/*member: anonymousClass:[null|subclass=LegacyJavaScriptObject]*/
 anonymousClass() => new Class1(a: 1, b: '');
 
 @JS()
@@ -43,9 +43,9 @@
 /*member: jsInteropClass:[subclass=JSInt]*/
 jsInteropClass() {
   JsInteropClass cls = new JsInteropClass();
-  return cls. /*update: [null|subclass=JavaScriptObject]*/ setter =
-      cls. /*[null|subclass=JavaScriptObject]*/ getter /*invoke: [null|subclass=JSInt]*/ +
-          cls. /*invoke: [subclass=JavaScriptObject]*/ method(
+  return cls. /*update: [null|subclass=LegacyJavaScriptObject]*/ setter =
+      cls. /*[null|subclass=LegacyJavaScriptObject]*/ getter /*invoke: [null|subclass=JSInt]*/ +
+          cls. /*invoke: [subclass=LegacyJavaScriptObject]*/ method(
               0) /*invoke: [subclass=JSInt]*/ +
           10;
 }
diff --git a/pkg/compiler/test/jsinterop/internal_annotations_test.dart b/pkg/compiler/test/jsinterop/internal_annotations_test.dart
index efea232..4299a38 100644
--- a/pkg/compiler/test/jsinterop/internal_annotations_test.dart
+++ b/pkg/compiler/test/jsinterop/internal_annotations_test.dart
@@ -106,6 +106,8 @@
         registerClass(world.commonElements.jsInterceptorClass);
     ClassEntity JavaScriptObject =
         registerClass(world.commonElements.jsJavaScriptObjectClass);
+    ClassEntity LegacyJavaScriptObject =
+        registerClass(world.commonElements.jsLegacyJavaScriptObjectClass);
     ClassEntity A = registerClass(findClass(world, 'A'));
     ClassEntity B = registerClass(findClass(world, 'B'));
     ClassEntity C = registerClass(findClass(world, 'C'));
@@ -118,11 +120,13 @@
     Expect.equals(elementEnvironment.getSuperClass(Interceptor), Object_);
     Expect.equals(
         elementEnvironment.getSuperClass(JavaScriptObject), Interceptor);
+    Expect.equals(elementEnvironment.getSuperClass(LegacyJavaScriptObject),
+        JavaScriptObject);
 
-    Expect.equals(elementEnvironment.getSuperClass(A), JavaScriptObject);
-    Expect.equals(elementEnvironment.getSuperClass(B), JavaScriptObject);
-    Expect.equals(elementEnvironment.getSuperClass(C), JavaScriptObject);
-    Expect.equals(elementEnvironment.getSuperClass(D), JavaScriptObject);
+    Expect.equals(elementEnvironment.getSuperClass(A), LegacyJavaScriptObject);
+    Expect.equals(elementEnvironment.getSuperClass(B), LegacyJavaScriptObject);
+    Expect.equals(elementEnvironment.getSuperClass(C), LegacyJavaScriptObject);
+    Expect.equals(elementEnvironment.getSuperClass(D), LegacyJavaScriptObject);
     Expect.equals(elementEnvironment.getSuperClass(E), Object_);
     Expect.equals(elementEnvironment.getSuperClass(F), Object_);
 
@@ -191,28 +195,69 @@
 
   await test('main() {}');
 
-  await test('main() => newA();',
-      abstractlyInstantiated: ['A', 'B', 'C', 'D'],
-      indirectlyInstantiated: ['Object', 'Interceptor', 'JavaScriptObject']);
+  await test('main() => newA();', abstractlyInstantiated: [
+    'A',
+    'B',
+    'C',
+    'D'
+  ], indirectlyInstantiated: [
+    'Object',
+    'Interceptor',
+    'JavaScriptObject',
+    'LegacyJavaScriptObject'
+  ]);
 
-  await test('main() => newB();',
-      abstractlyInstantiated: ['A', 'B', 'C', 'D'],
-      indirectlyInstantiated: ['Object', 'Interceptor', 'JavaScriptObject']);
+  await test('main() => newB();', abstractlyInstantiated: [
+    'A',
+    'B',
+    'C',
+    'D'
+  ], indirectlyInstantiated: [
+    'Object',
+    'Interceptor',
+    'JavaScriptObject',
+    'LegacyJavaScriptObject'
+  ]);
 
-  await test('main() => newC();',
-      abstractlyInstantiated: ['A', 'B', 'C', 'D'],
-      indirectlyInstantiated: ['Object', 'Interceptor', 'JavaScriptObject']);
+  await test('main() => newC();', abstractlyInstantiated: [
+    'A',
+    'B',
+    'C',
+    'D'
+  ], indirectlyInstantiated: [
+    'Object',
+    'Interceptor',
+    'JavaScriptObject',
+    'LegacyJavaScriptObject'
+  ]);
 
-  await test('main() => newD();',
-      abstractlyInstantiated: ['A', 'B', 'C', 'D'],
-      indirectlyInstantiated: ['Object', 'Interceptor', 'JavaScriptObject']);
+  await test('main() => newD();', abstractlyInstantiated: [
+    'A',
+    'B',
+    'C',
+    'D'
+  ], indirectlyInstantiated: [
+    'Object',
+    'Interceptor',
+    'JavaScriptObject',
+    'LegacyJavaScriptObject'
+  ]);
 
   await test('main() => newE();', directlyInstantiated: ['E']);
 
   await test('main() => newF();', directlyInstantiated: ['F']);
 
-  await test('main() => [newD(), newE()];',
-      directlyInstantiated: ['E'],
-      abstractlyInstantiated: ['A', 'B', 'C', 'D'],
-      indirectlyInstantiated: ['Object', 'Interceptor', 'JavaScriptObject']);
+  await test('main() => [newD(), newE()];', directlyInstantiated: [
+    'E'
+  ], abstractlyInstantiated: [
+    'A',
+    'B',
+    'C',
+    'D'
+  ], indirectlyInstantiated: [
+    'Object',
+    'Interceptor',
+    'JavaScriptObject',
+    'LegacyJavaScriptObject'
+  ]);
 }
diff --git a/pkg/compiler/test/jsinterop/world_test.dart b/pkg/compiler/test/jsinterop/world_test.dart
index bc495ac..6c3253f 100644
--- a/pkg/compiler/test/jsinterop/world_test.dart
+++ b/pkg/compiler/test/jsinterop/world_test.dart
@@ -100,6 +100,8 @@
         registerClass(world.commonElements.jsInterceptorClass);
     ClassEntity JavaScriptObject =
         registerClass(world.commonElements.jsJavaScriptObjectClass);
+    ClassEntity LegacyJavaScriptObject =
+        registerClass(world.commonElements.jsLegacyJavaScriptObjectClass);
     ClassEntity A = registerClass(findClass(world, 'A'));
     ClassEntity B = registerClass(findClass(world, 'B'));
     ClassEntity C = registerClass(findClass(world, 'C'));
@@ -112,11 +114,13 @@
     Expect.equals(elementEnvironment.getSuperClass(Interceptor), Object_);
     Expect.equals(
         elementEnvironment.getSuperClass(JavaScriptObject), Interceptor);
+    Expect.equals(elementEnvironment.getSuperClass(LegacyJavaScriptObject),
+        JavaScriptObject);
 
-    Expect.equals(elementEnvironment.getSuperClass(A), JavaScriptObject);
-    Expect.equals(elementEnvironment.getSuperClass(B), JavaScriptObject);
-    Expect.equals(elementEnvironment.getSuperClass(C), JavaScriptObject);
-    Expect.equals(elementEnvironment.getSuperClass(D), JavaScriptObject);
+    Expect.equals(elementEnvironment.getSuperClass(A), LegacyJavaScriptObject);
+    Expect.equals(elementEnvironment.getSuperClass(B), LegacyJavaScriptObject);
+    Expect.equals(elementEnvironment.getSuperClass(C), LegacyJavaScriptObject);
+    Expect.equals(elementEnvironment.getSuperClass(D), LegacyJavaScriptObject);
     Expect.equals(elementEnvironment.getSuperClass(E), Object_);
     Expect.equals(elementEnvironment.getSuperClass(F), Object_);
 
@@ -185,28 +189,69 @@
 
   await test('main() {}');
 
-  await test('main() => newA();',
-      abstractlyInstantiated: ['A', 'B', 'C', 'D'],
-      indirectlyInstantiated: ['Object', 'Interceptor', 'JavaScriptObject']);
+  await test('main() => newA();', abstractlyInstantiated: [
+    'A',
+    'B',
+    'C',
+    'D'
+  ], indirectlyInstantiated: [
+    'Object',
+    'Interceptor',
+    'JavaScriptObject',
+    'LegacyJavaScriptObject'
+  ]);
 
-  await test('main() => newB();',
-      abstractlyInstantiated: ['A', 'B', 'C', 'D'],
-      indirectlyInstantiated: ['Object', 'Interceptor', 'JavaScriptObject']);
+  await test('main() => newB();', abstractlyInstantiated: [
+    'A',
+    'B',
+    'C',
+    'D'
+  ], indirectlyInstantiated: [
+    'Object',
+    'Interceptor',
+    'JavaScriptObject',
+    'LegacyJavaScriptObject'
+  ]);
 
-  await test('main() => newC();',
-      abstractlyInstantiated: ['A', 'B', 'C', 'D'],
-      indirectlyInstantiated: ['Object', 'Interceptor', 'JavaScriptObject']);
+  await test('main() => newC();', abstractlyInstantiated: [
+    'A',
+    'B',
+    'C',
+    'D'
+  ], indirectlyInstantiated: [
+    'Object',
+    'Interceptor',
+    'JavaScriptObject',
+    'LegacyJavaScriptObject'
+  ]);
 
-  await test('main() => newD();',
-      abstractlyInstantiated: ['A', 'B', 'C', 'D'],
-      indirectlyInstantiated: ['Object', 'Interceptor', 'JavaScriptObject']);
+  await test('main() => newD();', abstractlyInstantiated: [
+    'A',
+    'B',
+    'C',
+    'D'
+  ], indirectlyInstantiated: [
+    'Object',
+    'Interceptor',
+    'JavaScriptObject',
+    'LegacyJavaScriptObject'
+  ]);
 
   await test('main() => newE();', directlyInstantiated: ['E']);
 
   await test('main() => newF();', directlyInstantiated: ['F']);
 
-  await test('main() => [newD(), newE()];',
-      directlyInstantiated: ['E'],
-      abstractlyInstantiated: ['A', 'B', 'C', 'D'],
-      indirectlyInstantiated: ['Object', 'Interceptor', 'JavaScriptObject']);
+  await test('main() => [newD(), newE()];', directlyInstantiated: [
+    'E'
+  ], abstractlyInstantiated: [
+    'A',
+    'B',
+    'C',
+    'D'
+  ], indirectlyInstantiated: [
+    'Object',
+    'Interceptor',
+    'JavaScriptObject',
+    'LegacyJavaScriptObject'
+  ]);
 }
diff --git a/pkg/compiler/test/rti/emission/jsinterop.dart b/pkg/compiler/test/rti/emission/jsinterop.dart
index f88db92..0e06b73 100644
--- a/pkg/compiler/test/rti/emission/jsinterop.dart
+++ b/pkg/compiler/test/rti/emission/jsinterop.dart
@@ -7,7 +7,7 @@
 @JS()
 library jsinterop;
 
-/*class: global#JavaScriptObject:checks=[$isA,$isC],instance*/
+/*class: global#LegacyJavaScriptObject:checks=[$isA,$isC],instance*/
 
 import 'package:js/js.dart';
 
diff --git a/pkg/compiler/test/rti/emission/jsinterop_generic.dart b/pkg/compiler/test/rti/emission/jsinterop_generic.dart
index d409967..31cade2 100644
--- a/pkg/compiler/test/rti/emission/jsinterop_generic.dart
+++ b/pkg/compiler/test/rti/emission/jsinterop_generic.dart
@@ -11,7 +11,7 @@
 
 // TODO(johnniwinther): Avoid generating duplicate is/as function when multiple
 // jsinterop classes implement the same interface.
-/*class: global#JavaScriptObject:checks=[$isA,$isB,$isB],instance*/
+/*class: global#LegacyJavaScriptObject:checks=[$isA,$isB,$isB],instance*/
 
 import 'package:expect/expect.dart';
 import 'package:js/js.dart';
diff --git a/pkg/compiler/test/rti/emission/jsinterop_generic_factory_args.dart b/pkg/compiler/test/rti/emission/jsinterop_generic_factory_args.dart
index 897ffea..77b181d 100644
--- a/pkg/compiler/test/rti/emission/jsinterop_generic_factory_args.dart
+++ b/pkg/compiler/test/rti/emission/jsinterop_generic_factory_args.dart
@@ -7,7 +7,7 @@
 @JS()
 library foo;
 
-/*class: global#JavaScriptObject:*/
+/*class: global#LegacyJavaScriptObject:*/
 
 import 'package:expect/expect.dart';
 import 'package:js/js.dart';
diff --git a/pkg/compiler/test/sourcemaps/helpers/sourcemap_helper.dart b/pkg/compiler/test/sourcemaps/helpers/sourcemap_helper.dart
index cc8df9a..424345f 100644
--- a/pkg/compiler/test/sourcemaps/helpers/sourcemap_helper.dart
+++ b/pkg/compiler/test/sourcemaps/helpers/sourcemap_helper.dart
@@ -271,7 +271,7 @@
 /// Visitor that collects all nodes that are within a function. Used by the
 /// [RecordingSourceInformationStrategy] to filter what is recorded in a
 /// [RecordedSourceInformationProcess].
-class FindVisitor extends js.BaseVisitor {
+class FindVisitor extends js.BaseVisitorVoid {
   final js.Node soughtNode;
   bool found = false;
   bool add = false;
@@ -280,7 +280,7 @@
   FindVisitor(this.soughtNode);
 
   @override
-  visitNode(js.Node node) {
+  void visitNode(js.Node node) {
     if (node == soughtNode) {
       found = true;
       add = true;
diff --git a/pkg/compiler/test/sourcemaps/nomapping_test.dart b/pkg/compiler/test/sourcemaps/nomapping_test.dart
index 7889b64..06cbf4f 100644
--- a/pkg/compiler/test/sourcemaps/nomapping_test.dart
+++ b/pkg/compiler/test/sourcemaps/nomapping_test.dart
@@ -31,7 +31,7 @@
     } else if (arg == '--write-js') {
       writeJs = true;
     } else {
-      int index = int.parse(arg, onError: (_) => null);
+      int index = int.tryParse(arg);
       if (index != null) {
         indices ??= <int>[];
         if (index < 0 || index >= TESTS.length * 2) {
diff --git a/pkg/compiler/test/sourcemaps/tools/diff_view.dart b/pkg/compiler/test/sourcemaps/tools/diff_view.dart
index 9f68323..9d245c3 100644
--- a/pkg/compiler/test/sourcemaps/tools/diff_view.dart
+++ b/pkg/compiler/test/sourcemaps/tools/diff_view.dart
@@ -866,12 +866,12 @@
 
 /// Visitor that computes a map from [js.Node]s to all attached source
 /// locations.
-class SourceLocationCollector extends js.BaseVisitor {
+class SourceLocationCollector extends js.BaseVisitorVoid {
   Map<js.Node, List<SourceLocation>> sourceLocations =
       <js.Node, List<SourceLocation>>{};
 
   @override
-  visitNode(js.Node node) {
+  void visitNode(js.Node node) {
     SourceInformation sourceInformation = node.sourceInformation;
     if (sourceInformation != null) {
       sourceLocations[node] = sourceInformation.sourceLocations;
diff --git a/pkg/dart2js_info/CHANGELOG.md b/pkg/dart2js_info/CHANGELOG.md
index ea4fe67b..6a617f6 100644
--- a/pkg/dart2js_info/CHANGELOG.md
+++ b/pkg/dart2js_info/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 0.6.6
+
+* Added the `comm` tool for finding commonalities between info files.
+
 ## 0.6.5
 
 * Drop unused dependencies.
diff --git a/pkg/dart2js_info/README.md b/pkg/dart2js_info/README.md
index 28ec26f..5f05010 100644
--- a/pkg/dart2js_info/README.md
+++ b/pkg/dart2js_info/README.md
@@ -92,7 +92,11 @@
     dependency between functions and fields in your program. Currently it only
     supports the `some_path` query, which shows a dependency path from one
     function to another.
-    
+
+  * [`common`][common]: a tool that reports the common elements of two info
+    files. Commonality is determined by the element's name, file path, and URI
+    but not code size.
+
   * [`diff`][diff]: a tool that diffs two info files and reports which
     program elements have been added, removed, or changed size. This also
     tells which elements are no longer deferred or have become deferred.
@@ -160,6 +164,44 @@
 If the name of a function your are looking for is unique enough, it might be
 sufficient to just write that name as your regular expression.
 
+### Common tool
+
+This command-line tool shows common elements between two info files. It can be
+run as follows:
+
+```console
+$ pub global activate dart2js_info # only needed once
+$ dart2js_info common old.js.info.data new.js.info.data
+```
+
+The tool gives a breakdown of the common elements between the two info files,
+reporting code size discrepancies if they exist.
+Here's an example output snippet:
+
+```
+COMMON ELEMENTS (455 common elements, 70334 bytes -> 70460 bytes)
+========================================================================
+dart:_foreign_helper::: 141 bytes
+dart:_foreign_helper::JS_CONST: 141 bytes
+dart:_foreign_helper::JS_CONST.code: 0 bytes
+dart:_interceptors::: 4052 -> 7968 bytes
+dart:_interceptors::ArrayIterator: 805 bytes
+dart:_interceptors::ArrayIterator.ArrayIterator: 0 bytes
+dart:_interceptors::ArrayIterator._current: 91 bytes
+dart:_interceptors::ArrayIterator._index: 0 bytes
+dart:_interceptors::ArrayIterator._iterable: 0 bytes
+dart:_interceptors::ArrayIterator._length: 0 bytes
+dart:_interceptors::ArrayIterator.current: 0 bytes
+dart:_interceptors::ArrayIterator.moveNext: 406 bytes
+dart:_interceptors::Interceptor: 198 bytes
+dart:_interceptors::Interceptor.toString: 104 -> 182 bytes
+
+```
+
+Common elements are sorted by name by default but can be sorted by size with
+the `--order-by-size` flag. Additionally, the tool can be restricted to
+just packages with the `--packages-only` flag.
+
 ### Diff tool
 
 This command-line tool shows a diff between two info files. It can be run
@@ -502,17 +544,18 @@
 This package is developed in [github][repo].  Please file feature requests and
 bugs at the [issue tracker][tracker].
 
-[repo]: https://github.com/dart-lang/dart2js_info/
-[tracker]: https://github.com/dart-lang/dart2js_info/issues
-[code_deps]: https://github.com/dart-lang/dart2js_info/blob/master/bin/code_deps.dart
-[diff]: https://github.com/dart-lang/dart2js_info/blob/master/bin/diff.dart
-[library_size]: https://github.com/dart-lang/dart2js_info/blob/master/bin/library_size_split.dart
-[deferred_check]: https://github.com/dart-lang/dart2js_info/blob/master/bin/deferred_library_check.dart
-[deferred_size]: https://github.com/dart-lang/dart2js_info/blob/master/bin/deferred_library_size.dart
-[deferred_layout]: https://github.com/dart-lang/dart2js_info/blob/master/bin/deferred_library_layout.dart
-[coverage_server]: https://github.com/dart-lang/dart2js_info/blob/master/bin/coverage_log_server.dart
-[coverage_analysis]: https://github.com/dart-lang/dart2js_info/blob/master/bin/live_code_size_analysis.dart
-[function_size]: https://github.com/dart-lang/dart2js_info/blob/master/bin/function_size_analysis.dart
-[AllInfo]: http://dart-lang.github.io/dart2js_info/doc/api/dart2js_info.info/AllInfo-class.html
-[convert]: https://github.com/dart-lang/dart2js_info/blob/master/bin/convert.dart
-[show]: https://github.com/dart-lang/dart2js_info/blob/master/bin/text_print.dart
+[AllInfo]: https://pub.dev/documentation/dart2js_info/latest/dart2js_info.info/AllInfo-class.html
+[code_deps]: https://github.com/dart-lang/sdk/tree/main/pkg/dart2js_info/bin/src/code_deps.dart
+[common]: https://github.com/dart-lang/sdk/tree/main/pkg/dart2js_info/bin/src/common_command.dart
+[convert]: https://github.com/dart-lang/sdk/tree/main/pkg/dart2js_info/bin/convert.dart
+[coverage_server]: https://github.com/dart-lang/sdk/tree/main/pkg/dart2js_info/bin/src/coverage_log_server.dart
+[coverage_analysis]: https://github.com/dart-lang/sdk/tree/main/pkg/dart2js_info/bin/src/live_code_size_analysis.dart
+[deferred_check]: https://github.com/dart-lang/sdk/tree/main/pkg/dart2js_info/bin/src/deferred_library_check.dart
+[deferred_layout]: https://github.com/dart-lang/sdk/tree/main/pkg/dart2js_info/bin/src/deferred_library_layout.dart
+[deferred_size]: https://github.com/dart-lang/sdk/tree/main/pkg/dart2js_info/bin/src/deferred_library_size.dart
+[diff]: https://github.com/dart-lang/sdk/tree/main/pkg/dart2js_info/bin/src/diff.dart
+[function_size]: https://github.com/dart-lang/sdk/tree/main/pkg/dart2js_info/bin/src/function_size_analysis.dart
+[library_size]: https://github.com/dart-lang/sdk/tree/main/pkg/dart2js_info/bin/src/library_size_split.dart
+[repo]: https://github.com/dart-lang/sdk/tree/main/pkg/dart2js_info/
+[show]: https://github.com/dart-lang/sdk/tree/main/pkg/dart2js_info/bin/src/text_print.dart
+[tracker]: https://github.com/dart-lang/sdk/issues
diff --git a/pkg/dart2js_info/bin/src/common_command.dart b/pkg/dart2js_info/bin/src/common_command.dart
new file mode 100644
index 0000000..8719b11
--- /dev/null
+++ b/pkg/dart2js_info/bin/src/common_command.dart
@@ -0,0 +1,152 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:args/command_runner.dart';
+
+import 'package:dart2js_info/info.dart';
+import 'package:dart2js_info/src/common_element.dart';
+import 'package:dart2js_info/src/io.dart';
+import 'package:dart2js_info/src/util.dart';
+
+import 'usage_exception.dart';
+
+/// A command that computes the commonalities between two info files.
+class CommonCommand extends Command<void> with PrintUsageException {
+  @override
+  final String name = "common";
+  @override
+  final String description =
+      "See code element commonalities between two dump-info files.";
+
+  CommonCommand() {
+    argParser.addFlag('packages-only',
+        defaultsTo: false, help: "Show only packages in common");
+    argParser.addFlag('order-by-size',
+        defaultsTo: false,
+        help: "Show output ordered by size in bytes (decreasing). "
+            "If there are size discrepancies, orders by the first "
+            "dump-info file's reported size.");
+  }
+
+  @override
+  void run() async {
+    var args = argResults.rest;
+    if (args.length < 2) {
+      usageException(
+          'Missing arguments, expected two dump-info files to compare');
+      return;
+    }
+
+    var oldInfo = await infoFromFile(args[0]);
+    var newInfo = await infoFromFile(args[1]);
+    var packagesOnly = argResults['packages-only'];
+    var orderBySize = argResults['order-by-size'];
+
+    var commonElements = findCommonalities(oldInfo, newInfo);
+
+    if (packagesOnly) {
+      reportPackages(commonElements, orderBySize: orderBySize);
+    } else {
+      report(commonElements, orderBySize: orderBySize);
+    }
+  }
+}
+
+void report(List<CommonElement> commonElements, {orderBySize = false}) {
+  var oldSizeTotal = 0, newSizeTotal = 0;
+  for (var element in commonElements) {
+    // Only sum sizes from leaf elements so we don't double count.
+    if (element.oldInfo.kind == InfoKind.field ||
+        element.oldInfo.kind == InfoKind.function ||
+        element.oldInfo.kind == InfoKind.closure ||
+        element.oldInfo.kind == InfoKind.typedef) {
+      oldSizeTotal += element.oldInfo.size;
+      newSizeTotal += element.newInfo.size;
+    }
+  }
+
+  _section('COMMON ELEMENTS',
+      elementCount: commonElements.length,
+      oldSizeTotal: oldSizeTotal,
+      newSizeTotal: newSizeTotal);
+
+  if (orderBySize) {
+    commonElements.sort((a, b) => b.oldInfo.size.compareTo(a.oldInfo.size));
+  } else {
+    commonElements.sort((a, b) => a.name.compareTo(b.name));
+  }
+
+  for (var element in commonElements) {
+    var oldSize = element.oldInfo.size;
+    var newSize = element.newInfo.size;
+    if (oldSize == newSize) {
+      print('${element.name}: ${element.oldInfo.size} bytes');
+    } else {
+      print('${element.name}: ${element.oldInfo.size} -> '
+          '${element.newInfo.size} bytes');
+    }
+  }
+}
+
+void reportPackages(List<CommonElement> commonElements, {orderBySize = false}) {
+  // Maps package names to their cumulative size.
+  var oldPackageInfo = <String, int>{};
+  var newPackageInfo = <String, int>{};
+
+  for (int i = 0; i < commonElements.length; i++) {
+    var element = commonElements[i];
+    // Skip non-libraries to avoid double counting elements when accumulating
+    // package-level information.
+    if (element.oldInfo.kind != InfoKind.library) continue;
+
+    var package = packageName(element.oldInfo);
+    if (package == null) continue;
+
+    var oldSize = element.oldInfo.size;
+    var newSize = element.newInfo.size;
+    oldPackageInfo[package] = (oldPackageInfo[package] ?? 0) + oldSize;
+    newPackageInfo[package] = (newPackageInfo[package] ?? 0) + newSize;
+  }
+
+  var oldSizeTotal = 0, newSizeTotal = 0;
+  oldPackageInfo.forEach((oldPackageName, oldPackageSize) {
+    var newPackageSize = newPackageInfo[oldPackageName];
+    oldSizeTotal += oldPackageSize;
+    newSizeTotal += newPackageSize;
+  });
+
+  _section('COMMON ELEMENTS (PACKAGES)',
+      elementCount: oldPackageInfo.keys.length,
+      oldSizeTotal: oldSizeTotal,
+      newSizeTotal: newSizeTotal);
+
+  var packageInfoEntries = oldPackageInfo.entries.toList();
+
+  if (orderBySize) {
+    packageInfoEntries.sort((a, b) => b.value.compareTo(a.value));
+  } else {
+    packageInfoEntries.sort((a, b) => a.key.compareTo(b.key));
+  }
+
+  for (var entry in packageInfoEntries) {
+    var oldSize = entry.value;
+    var newSize = newPackageInfo[entry.key];
+    if (oldSize == newSize) {
+      print('${entry.key}: $oldSize bytes');
+    } else {
+      print('${entry.key}: $oldSize bytes -> $newSize bytes');
+    }
+  }
+}
+
+void _section(String title,
+    {int elementCount, int oldSizeTotal, int newSizeTotal}) {
+  if (oldSizeTotal == newSizeTotal) {
+    print('$title ($elementCount common elements, $oldSizeTotal bytes)');
+  } else {
+    print('$title ($elementCount common elements, '
+        '$oldSizeTotal bytes -> $newSizeTotal bytes)');
+  }
+  print('=' * 72);
+}
diff --git a/pkg/dart2js_info/bin/tools.dart b/pkg/dart2js_info/bin/tools.dart
index 26a188b..9e2cda8 100644
--- a/pkg/dart2js_info/bin/tools.dart
+++ b/pkg/dart2js_info/bin/tools.dart
@@ -5,6 +5,7 @@
 import 'package:args/command_runner.dart';
 
 import 'src/code_deps.dart';
+import 'src/common_command.dart';
 import 'src/coverage_log_server.dart';
 import 'src/debug_info.dart';
 import 'src/diff.dart';
@@ -23,6 +24,7 @@
   var commandRunner = CommandRunner("dart2js_info",
       "collection of tools to digest the output of dart2js's --dump-info")
     ..addCommand(CodeDepsCommand())
+    ..addCommand(CommonCommand())
     ..addCommand(CoverageLogServerCommand())
     ..addCommand(DebugCommand())
     ..addCommand(DiffCommand())
diff --git a/pkg/dart2js_info/lib/src/common_element.dart b/pkg/dart2js_info/lib/src/common_element.dart
new file mode 100644
index 0000000..788d6f2
--- /dev/null
+++ b/pkg/dart2js_info/lib/src/common_element.dart
@@ -0,0 +1,116 @@
+import 'package:dart2js_info/info.dart';
+import 'package:dart2js_info/src/util.dart';
+
+class CommonElement {
+  final BasicInfo oldInfo;
+  final BasicInfo newInfo;
+
+  CommonElement(this.oldInfo, this.newInfo);
+
+  get name => longName(oldInfo, useLibraryUri: true);
+}
+
+List<CommonElement> findCommonalities(AllInfo oldInfo, AllInfo newInfo) {
+  var finder = _InfoCommonElementFinder(oldInfo, newInfo);
+  finder.run();
+  return finder.commonElements;
+}
+
+class _InfoCommonElementFinder extends InfoVisitor<void> {
+  final AllInfo _old;
+  final AllInfo _new;
+
+  BasicInfo _other;
+
+  List<CommonElement> commonElements = <CommonElement>[];
+
+  _InfoCommonElementFinder(this._old, this._new);
+
+  void run() {
+    _commonList(_old.libraries, _new.libraries);
+  }
+
+  @override
+  visitAll(AllInfo info) {
+    throw StateError('should not run common on AllInfo');
+  }
+
+  @override
+  visitProgram(ProgramInfo info) {
+    throw StateError('should not run common on ProgramInfo');
+  }
+
+  @override
+  visitOutput(OutputUnitInfo info) {
+    throw StateError('should not run common on OutputUnitInfo');
+  }
+
+  @override
+  visitConstant(ConstantInfo info) {
+    throw StateError('should not run common on ConstantInfo');
+  }
+
+  @override
+  visitLibrary(LibraryInfo info) {
+    var other = _other as LibraryInfo;
+    commonElements.add(CommonElement(info, other));
+    _commonList(info.topLevelVariables, other.topLevelVariables);
+    _commonList(info.topLevelFunctions, other.topLevelFunctions);
+    _commonList(info.classes, other.classes);
+  }
+
+  @override
+  visitClass(ClassInfo info) {
+    var other = _other as ClassInfo;
+    commonElements.add(CommonElement(info, other));
+    _commonList(info.fields, other.fields);
+    _commonList(info.functions, other.functions);
+  }
+
+  @override
+  visitClassType(ClassTypeInfo info) {
+    var other = _other as ClassInfo;
+    commonElements.add(CommonElement(info, other));
+  }
+
+  @override
+  visitClosure(ClosureInfo info) {
+    var other = _other as ClosureInfo;
+    commonElements.add(CommonElement(info, other));
+    _commonList([info.function], [other.function]);
+  }
+
+  @override
+  visitField(FieldInfo info) {
+    var other = _other as FieldInfo;
+    commonElements.add(CommonElement(info, other));
+    _commonList(info.closures, other.closures);
+  }
+
+  @override
+  visitFunction(FunctionInfo info) {
+    var other = _other as FunctionInfo;
+    commonElements.add(CommonElement(info, other));
+    _commonList(info.closures, other.closures);
+  }
+
+  @override
+  visitTypedef(TypedefInfo info) {
+    var other = _other as ClassInfo;
+    commonElements.add(CommonElement(info, other));
+  }
+
+  void _commonList(List<BasicInfo> oldInfos, List<BasicInfo> newInfos) {
+    var newNames = <String, BasicInfo>{};
+    for (var newInfo in newInfos) {
+      newNames[longName(newInfo, useLibraryUri: true)] = newInfo;
+    }
+    for (var oldInfo in oldInfos) {
+      var oldName = longName(oldInfo, useLibraryUri: true);
+      if (newNames.containsKey(oldName)) {
+        _other = newNames[oldName];
+        oldInfo.accept(this);
+      }
+    }
+  }
+}
diff --git a/pkg/dart2js_info/lib/src/util.dart b/pkg/dart2js_info/lib/src/util.dart
index e435458..eebb1c7 100644
--- a/pkg/dart2js_info/lib/src/util.dart
+++ b/pkg/dart2js_info/lib/src/util.dart
@@ -90,6 +90,19 @@
   return sb.toString();
 }
 
+/// Provides the package name associated with [info] or null otherwise.
+String packageName(Info info) {
+  while (info.parent != null) {
+    info = info.parent;
+  }
+  if (info is LibraryInfo) {
+    if (info.uri.scheme == 'package') {
+      return '${info.uri}'.split('/').first;
+    }
+  }
+  return null;
+}
+
 /// Produce a string containing [value] padded with white space up to [n] chars.
 pad(value, n, {bool right = false}) {
   var s = '$value';
diff --git a/pkg/dart2js_info/test/hello_world_deferred/hello_world_deferred.js.info.json b/pkg/dart2js_info/test/hello_world_deferred/hello_world_deferred.js.info.json
index 490a537..8e31503 100644
--- a/pkg/dart2js_info/test/hello_world_deferred/hello_world_deferred.js.info.json
+++ b/pkg/dart2js_info/test/hello_world_deferred/hello_world_deferred.js.info.json
@@ -2012,7 +2012,7 @@
       "851867060": {
         "id": "class/851867060",
         "kind": "class",
-        "name": "JavaScriptObject",
+        "name": "LegacyJavaScriptObject",
         "size": 225,
         "outputUnit": "outputUnit/669725655",
         "parent": "library/325218131",
diff --git a/pkg/dart_internal/analysis_options.yaml b/pkg/dart_internal/analysis_options.yaml
index edcd64e..6f7501d 100644
--- a/pkg/dart_internal/analysis_options.yaml
+++ b/pkg/dart_internal/analysis_options.yaml
@@ -1,5 +1,5 @@
 analyzer:
   errors:
     import_internal_library: ignore
-  strong-mode:
-    implicit-casts: false
+  language:
+    strict-casts: true
diff --git a/pkg/dartdev/lib/dartdev.dart b/pkg/dartdev/lib/dartdev.dart
index a545f1a..3e75181 100644
--- a/pkg/dartdev/lib/dartdev.dart
+++ b/pkg/dartdev/lib/dartdev.dart
@@ -21,6 +21,7 @@
 import 'src/commands/compile.dart';
 import 'src/commands/create.dart';
 import 'src/commands/debug_adapter.dart';
+import 'src/commands/doc.dart';
 import 'src/commands/fix.dart';
 import 'src/commands/language_server.dart';
 import 'src/commands/migrate.dart';
@@ -114,6 +115,7 @@
     addCommand(CreateCommand(verbose: verbose));
     addCommand(DebugAdapterCommand(verbose: verbose));
     addCommand(CompileCommand(verbose: verbose));
+    addCommand(DocCommand(verbose: verbose));
     addCommand(DevToolsCommand(
       verbose: verbose,
       customDevToolsPath: sdk.devToolsBinaries,
diff --git a/pkg/dartdev/lib/src/commands/doc.dart b/pkg/dartdev/lib/src/commands/doc.dart
new file mode 100644
index 0000000..d039183
--- /dev/null
+++ b/pkg/dartdev/lib/src/commands/doc.dart
@@ -0,0 +1,89 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:async';
+import 'dart:io' as io;
+
+import 'package:dartdoc/dartdoc.dart';
+import 'package:dartdoc/options.dart';
+import 'package:path/path.dart' as path;
+
+import '../core.dart';
+import '../sdk.dart';
+
+/// A command to create a new project from a set of templates.
+class DocCommand extends DartdevCommand {
+  static const String cmdName = 'doc';
+
+  DocCommand({bool verbose = false})
+      : super(
+          cmdName,
+          'Generate HTML API documentation from Dart documentation comments.',
+          verbose,
+        ) {
+    argParser.addOption(
+      'output-dir',
+      abbr: 'o',
+      defaultsTo: path.join('.', 'doc', 'api'),
+      help: 'Output directory',
+    );
+    argParser.addFlag(
+      'validate-links',
+      negatable: true,
+      help: 'Display context aware warnings for broken links (slow)',
+    );
+  }
+
+  @override
+  String get invocation => '${super.invocation} <input directory>';
+
+  @override
+  FutureOr<int> run() async {
+    // At least one argument, the input directory, is required.
+    if (argResults.rest.isEmpty) {
+      usageException("Error: Input directory not specified");
+    }
+
+    // Determine input directory.
+    final dir = io.Directory(argResults.rest[0]);
+    if (!dir.existsSync()) {
+      usageException("Error: Input directory doesn't exist: ${dir.path}");
+    }
+
+    // Parse options.
+    final options = [
+      '--input=${dir.path}',
+      '--output=${argResults['output-dir']}',
+    ];
+    if (argResults['validate-links']) {
+      options.add('--validate-links');
+    } else {
+      options.add('--no-validate-links');
+    }
+
+    // Specify where dartdoc resources are located.
+    final resourcesPath =
+        path.absolute(sdk.sdkPath, 'bin', 'resources', 'dartdoc', 'resources');
+    options.add('--resources-dir=$resourcesPath');
+
+    final config = await parseOptions(pubPackageMetaProvider, options);
+    if (config == null) {
+      // There was an error while parsing options.
+      return 2;
+    }
+
+    // Call dartdoc.
+    if (verbose) {
+      log.stdout('Calling dartdoc with the following options: $options');
+    }
+    final packageConfigProvider = PhysicalPackageConfigProvider();
+    final packageBuilder = PubPackageBuilder(
+        config, pubPackageMetaProvider, packageConfigProvider);
+    final dartdoc = config.generateDocs
+        ? await Dartdoc.fromContext(config, packageBuilder)
+        : await Dartdoc.withEmptyGenerator(config, packageBuilder);
+    dartdoc.executeGuarded();
+    return 0;
+  }
+}
diff --git a/pkg/dartdev/lib/src/commands/fix.dart b/pkg/dartdev/lib/src/commands/fix.dart
index d6c8b5a..1bdb252 100644
--- a/pkg/dartdev/lib/src/commands/fix.dart
+++ b/pkg/dartdev/lib/src/commands/fix.dart
@@ -6,7 +6,6 @@
 import 'dart:io' as io;
 
 import 'package:analysis_server_client/protocol.dart' hide AnalysisError;
-import 'package:intl/intl.dart';
 import 'package:meta/meta.dart';
 import 'package:path/path.dart' as path;
 
@@ -18,8 +17,6 @@
 class FixCommand extends DartdevCommand {
   static const String cmdName = 'fix';
 
-  static final NumberFormat _numberFormat = NumberFormat.decimalPattern();
-
   static const String cmdDescription =
       '''Apply automated fixes to Dart source code.
 
@@ -152,16 +149,16 @@
 
       if (dryRun) {
         log.stdout('');
-        log.stdout('${_format(fixCount)} proposed ${_pluralFix(fixCount)} '
-            'in ${_format(fileCount)} ${pluralize("file", fileCount)}.');
+        log.stdout('$fixCount proposed ${_pluralFix(fixCount)} '
+            'in $fileCount ${pluralize("file", fileCount)}.');
         _printDetails(detailsMap, dir);
       } else {
         var applyFixesProgress = log.progress('Applying fixes');
         _writeFiles();
         applyFixesProgress.finish(showTiming: true);
         _printDetails(detailsMap, dir);
-        log.stdout('${_format(fixCount)} ${_pluralFix(fixCount)} made in '
-            '${_format(fileCount)} ${pluralize("file", fileCount)}.');
+        log.stdout('$fixCount ${_pluralFix(fixCount)} made in '
+            '$fileCount ${pluralize("file", fileCount)}.');
       }
     }
 
@@ -314,7 +311,7 @@
       fixes.sort((a, b) => a.code.compareTo(b.code));
       for (var fix in fixes) {
         log.stdout('  ${fix.code} $bullet '
-            '${_format(fix.occurrences)} ${_pluralFix(fix.occurrences)}');
+            '${fix.occurrences} ${_pluralFix(fix.occurrences)}');
       }
       log.stdout('');
     }
@@ -343,8 +340,6 @@
       file.writeAsStringSync(entry.value);
     }
   }
-
-  static String _format(int value) => _numberFormat.format(value);
 }
 
 /// The result of running tests in a given directory.
diff --git a/pkg/dartdev/pubspec.yaml b/pkg/dartdev/pubspec.yaml
index 0145fab..9d78178 100644
--- a/pkg/dartdev/pubspec.yaml
+++ b/pkg/dartdev/pubspec.yaml
@@ -17,12 +17,12 @@
   dart2native:
     path: ../dart2native
   dart_style: any
+  dartdoc: any
   dds:
     path: ../dds
   devtools_server: any
   front_end:
     path: ../front_end
-  intl: any
   meta:
     path: ../meta
   nnbd_migration:
diff --git a/pkg/dartdev/test/analysis_server_test.dart b/pkg/dartdev/test/analysis_server_test.dart
index 9902dda..975eb86 100644
--- a/pkg/dartdev/test/analysis_server_test.dart
+++ b/pkg/dartdev/test/analysis_server_test.dart
@@ -21,7 +21,7 @@
       p = project();
     });
 
-    tearDown(() => p?.dispose());
+    tearDown(() async => await p?.dispose());
 
     test('can start', () async {
       AnalysisServer server = AnalysisServer(
diff --git a/pkg/dartdev/test/commands/analyze_test.dart b/pkg/dartdev/test/commands/analyze_test.dart
index 11613ef..60bbb1a 100644
--- a/pkg/dartdev/test/commands/analyze_test.dart
+++ b/pkg/dartdev/test/commands/analyze_test.dart
@@ -176,7 +176,7 @@
 
   setUp(() => p = null);
 
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   test('--help', () async {
     p = project();
@@ -201,7 +201,7 @@
   group('multiple items', () {
     TestProject secondProject;
 
-    tearDown(() => secondProject?.dispose());
+    tearDown(() async => await secondProject?.dispose());
 
     test('folder and file', () async {
       p = project(mainSrc: "int get foo => 'str';\n");
diff --git a/pkg/dartdev/test/commands/create_integration_test.dart b/pkg/dartdev/test/commands/create_integration_test.dart
index e4363a4..4856b47 100644
--- a/pkg/dartdev/test/commands/create_integration_test.dart
+++ b/pkg/dartdev/test/commands/create_integration_test.dart
@@ -18,7 +18,7 @@
 
   setUp(() => p = null);
 
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   // Create tests for each template.
   for (String templateId in CreateCommand.legalTemplateIds) {
diff --git a/pkg/dartdev/test/commands/create_test.dart b/pkg/dartdev/test/commands/create_test.dart
index 6978d98..899c7b0 100644
--- a/pkg/dartdev/test/commands/create_test.dart
+++ b/pkg/dartdev/test/commands/create_test.dart
@@ -21,7 +21,7 @@
 
   setUp(() => p = null);
 
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   test('--help', () async {
     p = project();
diff --git a/pkg/dartdev/test/commands/devtools_test.dart b/pkg/dartdev/test/commands/devtools_test.dart
index 656b8c6..e14ba0ac 100644
--- a/pkg/dartdev/test/commands/devtools_test.dart
+++ b/pkg/dartdev/test/commands/devtools_test.dart
@@ -16,7 +16,7 @@
 void devtools() {
   TestProject p;
 
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   test('--help', () async {
     p = project();
diff --git a/pkg/dartdev/test/commands/doc_test.dart b/pkg/dartdev/test/commands/doc_test.dart
new file mode 100644
index 0000000..9f57108
--- /dev/null
+++ b/pkg/dartdev/test/commands/doc_test.dart
@@ -0,0 +1,70 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:test/test.dart';
+
+import '../utils.dart';
+
+const int compileErrorExitCode = 64;
+
+void main() {
+  group('doc', defineCompileTests, timeout: longTimeout);
+}
+
+void defineCompileTests() {
+  test('Passing no args fails', () async {
+    final p = project();
+    var result = await p.run(['doc']);
+    expect(result.stderr, contains('Input directory not specified'));
+    expect(result.exitCode, compileErrorExitCode);
+  });
+
+  test('--help', () async {
+    final p = project();
+    final result = await p.run(['doc', '--help']);
+    expect(
+      result.stdout,
+      contains('Usage: dart doc [arguments] <input directory>'),
+    );
+
+    expect(result.exitCode, 0);
+  });
+
+  test('Document a library', () async {
+    final source = '''
+/// This is Foo. It uses [Bar].
+class Foo {
+    Bar bar;
+}
+
+/// Bar is very nice.
+class Bar {
+    _i = 42;
+}
+    ''';
+
+    final p = project(mainSrc: 'void main() { print("Hello, World"); }');
+    p.file('lib/foo.dart', source);
+    final result = await p.run(['doc', '--validate-links', p.dirPath]);
+    print(
+        'exit: ${result.exitCode}, stderr:\n${result.stderr}\nstdout:\n${result.stdout}');
+    expect(result.stdout, contains('Documenting dartdev_temp'));
+  });
+
+  test('Document a library with broken link is flagged', () async {
+    final source = '''
+/// This is Foo. It uses [Baz].
+class Foo {
+  //  Bar bar;
+}
+    ''';
+
+    final p = project(mainSrc: 'void main() { print("Hello, World"); }');
+    p.file('lib/foo.dart', source);
+    final result = await p.run(['doc', '--validate-links', p.dirPath]);
+    print(
+        'exit: ${result.exitCode}, stderr:\n${result.stderr}\nstdout:\n${result.stdout}');
+    expect(result.stdout, contains('Documenting dartdev_temp'));
+  });
+}
diff --git a/pkg/dartdev/test/commands/fix_test.dart b/pkg/dartdev/test/commands/fix_test.dart
index 1f0dd94..c6382f4 100644
--- a/pkg/dartdev/test/commands/fix_test.dart
+++ b/pkg/dartdev/test/commands/fix_test.dart
@@ -26,7 +26,7 @@
 
   setUp(() => p = null);
 
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   void assertResult({int exitCode = 0}) {
     String message;
diff --git a/pkg/dartdev/test/commands/flag_test.dart b/pkg/dartdev/test/commands/flag_test.dart
index b5aa76e..3feab2d 100644
--- a/pkg/dartdev/test/commands/flag_test.dart
+++ b/pkg/dartdev/test/commands/flag_test.dart
@@ -57,7 +57,7 @@
 void help() {
   TestProject p;
 
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   test('--help', () async {
     p = project();
diff --git a/pkg/dartdev/test/commands/format_test.dart b/pkg/dartdev/test/commands/format_test.dart
index 5331c6d..cf82970 100644
--- a/pkg/dartdev/test/commands/format_test.dart
+++ b/pkg/dartdev/test/commands/format_test.dart
@@ -16,7 +16,7 @@
 void format() {
   TestProject p;
 
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   test('--help', () async {
     p = project();
diff --git a/pkg/dartdev/test/commands/help_test.dart b/pkg/dartdev/test/commands/help_test.dart
index 2202b56..69f1f27 100644
--- a/pkg/dartdev/test/commands/help_test.dart
+++ b/pkg/dartdev/test/commands/help_test.dart
@@ -15,7 +15,7 @@
 void help() {
   TestProject p;
 
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   /// Commands not tested by the following loop.
   List<String> _commandsNotTested = <String>[
diff --git a/pkg/dartdev/test/commands/language_server_test.dart b/pkg/dartdev/test/commands/language_server_test.dart
index 1e7a46d..543aec9 100644
--- a/pkg/dartdev/test/commands/language_server_test.dart
+++ b/pkg/dartdev/test/commands/language_server_test.dart
@@ -24,10 +24,7 @@
   utils.TestProject project;
   Process process;
 
-  tearDown(() {
-    project?.dispose();
-    process?.kill();
-  });
+  tearDown(() async => await project?.dispose());
 
   Future runWithLsp(List<String> args) async {
     project = utils.project();
diff --git a/pkg/dartdev/test/commands/migrate_test.dart b/pkg/dartdev/test/commands/migrate_test.dart
index 68475ee..0b394ad 100644
--- a/pkg/dartdev/test/commands/migrate_test.dart
+++ b/pkg/dartdev/test/commands/migrate_test.dart
@@ -17,7 +17,7 @@
 
   TestProject p;
 
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   test('--help', () async {
     p = project();
diff --git a/pkg/dartdev/test/commands/pub_test.dart b/pkg/dartdev/test/commands/pub_test.dart
index 2eafe5e..f2486dd 100644
--- a/pkg/dartdev/test/commands/pub_test.dart
+++ b/pkg/dartdev/test/commands/pub_test.dart
@@ -15,7 +15,7 @@
 void pub() {
   TestProject p;
 
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   void _assertPubHelpInvoked(ProcessResult result) {
     expect(result, isNotNull);
diff --git a/pkg/dartdev/test/commands/run_test.dart b/pkg/dartdev/test/commands/run_test.dart
index 1e9b3e0..f3174c7 100644
--- a/pkg/dartdev/test/commands/run_test.dart
+++ b/pkg/dartdev/test/commands/run_test.dart
@@ -23,7 +23,7 @@
 void run() {
   TestProject p;
 
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   test('--help', () async {
     p = project();
@@ -147,7 +147,7 @@
       expect(result.stdout, contains('FOO BAR [--arg1, arg2]'));
       expect(result.exitCode, 0);
     } finally {
-      bar.dispose();
+      await bar.dispose();
     }
   });
 
diff --git a/pkg/dartdev/test/commands/test_test.dart b/pkg/dartdev/test/commands/test_test.dart
index 634d2b9..7f758d3 100644
--- a/pkg/dartdev/test/commands/test_test.dart
+++ b/pkg/dartdev/test/commands/test_test.dart
@@ -19,7 +19,7 @@
 void defineTest(List<Experiment> experiments) {
   TestProject p;
 
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   test('--help', () async {
     p = project();
diff --git a/pkg/dartdev/test/core_test.dart b/pkg/dartdev/test/core_test.dart
index 5f49133..f9c8e29 100644
--- a/pkg/dartdev/test/core_test.dart
+++ b/pkg/dartdev/test/core_test.dart
@@ -105,7 +105,7 @@
 void _project() {
   TestProject p;
 
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   test('hasPubspecFile positive', () {
     p = project();
diff --git a/pkg/dartdev/test/fix_driver_test.dart b/pkg/dartdev/test/fix_driver_test.dart
index 35ec72a..8b71804 100644
--- a/pkg/dartdev/test/fix_driver_test.dart
+++ b/pkg/dartdev/test/fix_driver_test.dart
@@ -19,7 +19,7 @@
 
 void _driver() {
   TestProject p;
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   test('no fixes', () async {
     p = project(mainSrc: 'int get foo => 1;\n');
diff --git a/pkg/dartdev/test/load_from_dill_test.dart b/pkg/dartdev/test/load_from_dill_test.dart
index 633e7af..0412854 100644
--- a/pkg/dartdev/test/load_from_dill_test.dart
+++ b/pkg/dartdev/test/load_from_dill_test.dart
@@ -11,7 +11,7 @@
 void main() {
   TestProject p;
 
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   test("Fallback to dartdev.dill from dartdev.dart.snapshot for 'Hello World'",
       () async {
diff --git a/pkg/dartdev/test/no_such_file_test.dart b/pkg/dartdev/test/no_such_file_test.dart
index 9b2edc4..bf4eaa3 100644
--- a/pkg/dartdev/test/no_such_file_test.dart
+++ b/pkg/dartdev/test/no_such_file_test.dart
@@ -9,7 +9,7 @@
 void main() {
   TestProject p;
 
-  tearDown(() => p?.dispose());
+  tearDown(() async => await p?.dispose());
 
   test('Ensure parsing fails after encountering invalid file', () async {
     // Regression test for https://github.com/dart-lang/sdk/issues/43991
diff --git a/pkg/dartdev/test/utils.dart b/pkg/dartdev/test/utils.dart
index fe656a5..8f8147a 100644
--- a/pkg/dartdev/test/utils.dart
+++ b/pkg/dartdev/test/utils.dart
@@ -93,8 +93,9 @@
     file.deleteSync();
   }
 
-  void dispose() {
+  Future<void> dispose() async {
     _process?.kill();
+    await _process?.exitCode;
     _process = null;
     if (dir.existsSync()) {
       dir.deleteSync(recursive: true);
@@ -135,7 +136,8 @@
           ...arguments,
         ],
         workingDirectory: workingDir ?? dir.path,
-        environment: {if (logAnalytics) '_DARTDEV_LOG_ANALYTICS': 'true'});
+        environment: {if (logAnalytics) '_DARTDEV_LOG_ANALYTICS': 'true'})
+      ..then((p) => _process = p);
   }
 
   String _sdkRootPath;
diff --git a/pkg/dds/CHANGELOG.md b/pkg/dds/CHANGELOG.md
index 0b7db0f..3b33fd2 100644
--- a/pkg/dds/CHANGELOG.md
+++ b/pkg/dds/CHANGELOG.md
@@ -1,3 +1,6 @@
+# 2.1.6
+- Improve performance of CPU sample caching.
+
 # 2.1.5
 - Update to new CpuSamplesEvent format for CPU sample caching for improved
   performance.
diff --git a/pkg/dds/lib/src/client.dart b/pkg/dds/lib/src/client.dart
index 771ccee..7aaeafd 100644
--- a/pkg/dds/lib/src/client.dart
+++ b/pkg/dds/lib/src/client.dart
@@ -107,6 +107,16 @@
       return RPCResponses.success;
     });
 
+    _clientPeer.registerMethod('streamCpuSamplesWithUserTag',
+        (parameters) async {
+      final userTags = parameters['userTags'].asList.cast<String>();
+      profilerUserTagFilters.clear();
+      profilerUserTagFilters.addAll(userTags);
+
+      await dds.streamManager.updateUserTagSubscriptions(userTags);
+      return RPCResponses.success;
+    });
+
     _clientPeer.registerMethod('registerService', (parameters) async {
       final serviceId = parameters['service'].asString;
       final alias = parameters['alias'].asString;
@@ -312,6 +322,7 @@
   final DartDevelopmentServiceImpl dds;
   final StreamChannel connection;
   final Map<String, String> services = {};
+  final Set<String> profilerUserTagFilters = {};
   final json_rpc.Peer _vmServicePeer;
   late json_rpc.Peer _clientPeer;
 }
diff --git a/pkg/dds/lib/src/cpu_samples_manager.dart b/pkg/dds/lib/src/cpu_samples_manager.dart
index 108da99..14b5c22 100644
--- a/pkg/dds/lib/src/cpu_samples_manager.dart
+++ b/pkg/dds/lib/src/cpu_samples_manager.dart
@@ -15,34 +15,15 @@
     }
   }
 
-  void handleUserTagEvent(Event event) {
-    assert(event.kind! == EventKind.kUserTagChanged);
-    _currentTag = event.updatedTag!;
-    final previousTag = event.previousTag!;
-    if (cpuSamplesCaches.containsKey(previousTag)) {
-      _lastCachedTag = previousTag;
-    }
-  }
-
   void handleCpuSamplesEvent(Event event) {
-    assert(event.kind! == EventKind.kCpuSamples);
-    // There might be some samples left in the buffer for the previously set
-    // user tag. We'll check for them here and then close out the cache.
-    if (_lastCachedTag != null) {
-      cpuSamplesCaches[_lastCachedTag]!.cacheSamples(
-        event.cpuSamples!,
-      );
-      _lastCachedTag = null;
+    for (final userTag in dds.cachedUserTags) {
+      cpuSamplesCaches[userTag]!.cacheSamples(event.cpuSamples!);
     }
-    cpuSamplesCaches[_currentTag]?.cacheSamples(event.cpuSamples!);
   }
 
   final DartDevelopmentServiceImpl dds;
   final String isolateId;
   final cpuSamplesCaches = <String, CpuSamplesRepository>{};
-
-  String _currentTag = '';
-  String? _lastCachedTag;
 }
 
 class CpuSamplesRepository extends RingBuffer<CpuSample> {
diff --git a/pkg/dds/lib/src/dap/adapters/mixins.dart b/pkg/dds/lib/src/dap/adapters/mixins.dart
index b9f307f..53de6fc 100644
--- a/pkg/dds/lib/src/dap/adapters/mixins.dart
+++ b/pkg/dds/lib/src/dap/adapters/mixins.dart
@@ -160,7 +160,7 @@
     final completer = Completer<Uri>();
     late final StreamSubscription<FileSystemEvent> vmServiceInfoFileWatcher;
 
-    Uri? tryParseServiceInfoFile(FileSystemEvent event) {
+    void tryParseServiceInfoFile(FileSystemEvent event) {
       final uri = _readVmServiceInfoFile(logger, vmServiceInfoFile);
       if (uri != null && !completer.isCompleted) {
         vmServiceInfoFileWatcher.cancel();
@@ -200,6 +200,7 @@
       // It's possible we tried to read the file before it was completely
       // written so ignore and try again on the next event.
       logger?.call('Ignoring error parsing vm-service-info file: $e');
+      return null;
     }
   }
 }
diff --git a/pkg/dds/lib/src/dap/isolate_manager.dart b/pkg/dds/lib/src/dap/isolate_manager.dart
index cbf2087..9fb0adf 100644
--- a/pkg/dds/lib/src/dap/isolate_manager.dart
+++ b/pkg/dds/lib/src/dap/isolate_manager.dart
@@ -375,6 +375,7 @@
         'Debugger failed to evaluate breakpoint $type "$expression": $e\n',
       );
     }
+    return null;
   }
 
   void _handleExit(vm.Event event) {
diff --git a/pkg/dds/lib/src/isolate_manager.dart b/pkg/dds/lib/src/isolate_manager.dart
index 7808b2a..93c2af4 100644
--- a/pkg/dds/lib/src/isolate_manager.dart
+++ b/pkg/dds/lib/src/isolate_manager.dart
@@ -123,9 +123,6 @@
 
   void handleEvent(Event event) {
     switch (event.kind) {
-      case EventKind.kUserTagChanged:
-        cpuSamplesManager.handleUserTagEvent(event);
-        return;
       case EventKind.kCpuSamples:
         cpuSamplesManager.handleCpuSamplesEvent(event);
         return;
@@ -239,6 +236,14 @@
             isolateStarted(id, name);
           }
         }
+        if (dds.cachedUserTags.isNotEmpty) {
+          await dds.vmServiceClient.sendRequest(
+            'streamCpuSamplesWithUserTag',
+            {
+              'userTags': dds.cachedUserTags,
+            },
+          );
+        }
       },
     );
     _initialized = true;
diff --git a/pkg/dds/lib/src/stream_manager.dart b/pkg/dds/lib/src/stream_manager.dart
index 46e22cf..ee0bc49 100644
--- a/pkg/dds/lib/src/stream_manager.dart
+++ b/pkg/dds/lib/src/stream_manager.dart
@@ -39,12 +39,36 @@
         if (isBinaryData) {
           listener.connection.sink.add(data);
         } else {
-          listener.sendNotification('streamNotify', data);
+          Map<String, dynamic> processed = data;
+          if (streamId == kProfilerStream) {
+            processed = _processProfilerEvents(listener, data);
+          }
+          listener.sendNotification('streamNotify', processed);
         }
       }
     }
   }
 
+  static Map<String, dynamic> _processProfilerEvents(
+    DartDevelopmentServiceClient client,
+    Map<String, dynamic> data,
+  ) {
+    final event = Event.parse(data['event'])!;
+    if (event.kind != EventKind.kCpuSamples) {
+      return data;
+    }
+    final cpuSamplesEvent = event.cpuSamples!;
+    cpuSamplesEvent.samples = cpuSamplesEvent.samples!
+        .where(
+          (e) => client.profilerUserTagFilters.contains(e.userTag),
+        )
+        .toList();
+    cpuSamplesEvent.sampleCount = cpuSamplesEvent.samples!.length;
+    final updated = Map<String, dynamic>.from(data);
+    updated['event']['cpuSamples'] = cpuSamplesEvent.toJson();
+    return updated;
+  }
+
   static Map<String, dynamic> _buildStreamRegisteredEvent(
           String namespace, String service, String alias) =>
       {
@@ -148,7 +172,7 @@
     DartDevelopmentServiceClient? client,
     String stream,
   ) async {
-    await _mutex.runGuarded(
+    await _streamSubscriptionMutex.runGuarded(
       () async {
         assert(stream.isNotEmpty);
         if (!streamListeners.containsKey(stream)) {
@@ -218,7 +242,7 @@
     String stream, {
     bool cancelCoreStream = false,
   }) async {
-    await _mutex.runGuarded(
+    await _streamSubscriptionMutex.runGuarded(
       () async {
         assert(stream.isNotEmpty);
         final listeners = streamListeners[stream];
@@ -246,6 +270,28 @@
     );
   }
 
+  Future<void> updateUserTagSubscriptions(
+      [List<String> userTags = const []]) async {
+    await _profilerUserTagSubscriptionsMutex.runGuarded(() async {
+      _profilerUserTagSubscriptions.addAll(userTags);
+      for (final subscribedTag in _profilerUserTagSubscriptions.toList()) {
+        bool hasSubscriber = false;
+        for (final c in dds.clientManager.clients) {
+          if (c.profilerUserTagFilters.contains(subscribedTag)) {
+            hasSubscriber = true;
+            break;
+          }
+        }
+        if (!hasSubscriber) {
+          _profilerUserTagSubscriptions.remove(subscribedTag);
+        }
+      }
+      await dds.vmServiceClient.sendRequest('streamCpuSamplesWithUserTag', {
+        'userTags': _profilerUserTagSubscriptions.toList(),
+      });
+    });
+  }
+
   /// Cleanup stream subscriptions for `client` when it has disconnected.
   void clientDisconnect(DartDevelopmentServiceClient client) {
     for (final streamId in streamListeners.keys.toList()) {
@@ -256,6 +302,11 @@
         test: (e) => (e is json_rpc.RpcException) || (e is StateError),
       );
     }
+    updateUserTagSubscriptions().catchError(
+      (_) => null,
+      test: (e) => (e is json_rpc.RpcException) || (e is StateError),
+    );
+
     // Notify other service clients of service extensions that are being
     // unregistered.
     _sendServiceUnregisteredEvents(client);
@@ -312,5 +363,7 @@
 
   final DartDevelopmentServiceImpl dds;
   final streamListeners = <String, List<DartDevelopmentServiceClient>>{};
-  final _mutex = Mutex();
+  final _profilerUserTagSubscriptions = <String>{};
+  final _streamSubscriptionMutex = Mutex();
+  final _profilerUserTagSubscriptionsMutex = Mutex();
 }
diff --git a/pkg/dds/pubspec.yaml b/pkg/dds/pubspec.yaml
index ef5124d..bc3e130 100644
--- a/pkg/dds/pubspec.yaml
+++ b/pkg/dds/pubspec.yaml
@@ -3,7 +3,7 @@
   A library used to spawn the Dart Developer Service, used to communicate with
   a Dart VM Service instance.
 
-version: 2.1.5
+version: 2.1.6
 
 homepage: https://github.com/dart-lang/sdk/tree/master/pkg/dds
 
diff --git a/pkg/dds/test/common/test_helper.dart b/pkg/dds/test/common/test_helper.dart
index 9fc441b..a9473ea 100644
--- a/pkg/dds/test/common/test_helper.dart
+++ b/pkg/dds/test/common/test_helper.dart
@@ -13,6 +13,7 @@
 Future<Process> spawnDartProcess(
   String script, {
   bool pauseOnStart = true,
+  bool disableServiceAuthCodes = false,
 }) async {
   final executable = Platform.executable;
   final tmpDir = await Directory.systemTemp.createTemp('dart_service');
@@ -23,6 +24,7 @@
     '--disable-dart-dev',
     '--observe=0',
     if (pauseOnStart) '--pause-isolates-on-start',
+    if (disableServiceAuthCodes) '--disable-service-auth-codes',
     '--write-service-info=$serviceInfoUri',
     ...Platform.executableArguments,
     Platform.script.resolve(script).toString(),
diff --git a/pkg/dds/test/cpu_sample_streaming_test.dart b/pkg/dds/test/cpu_sample_streaming_test.dart
new file mode 100644
index 0000000..f1f224a
--- /dev/null
+++ b/pkg/dds/test/cpu_sample_streaming_test.dart
@@ -0,0 +1,135 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:async';
+import 'dart:io';
+
+import 'package:dds/dds.dart';
+import 'package:test/test.dart';
+import 'package:vm_service/vm_service.dart';
+import 'package:vm_service/vm_service_io.dart';
+import 'common/test_helper.dart';
+
+void main() {
+  late Process process;
+  DartDevelopmentService? dds;
+
+  setUp(() async {
+    process = await spawnDartProcess(
+      'get_cached_cpu_samples_script.dart',
+      disableServiceAuthCodes: true,
+    );
+  });
+
+  tearDown(() async {
+    await dds?.shutdown();
+    process.kill();
+  });
+
+  void declareTest(bool withDds) {
+    test(
+      'Stream CPU samples for provided UserTag names with${withDds ? "" : "out"} DDS',
+      () async {
+        Uri serviceUri = remoteVmServiceUri;
+        if (withDds) {
+          dds = await DartDevelopmentService.startDartDevelopmentService(
+            remoteVmServiceUri,
+          );
+          serviceUri = dds!.wsUri!;
+          expect(dds!.isRunning, true);
+        } else {
+          serviceUri = serviceUri.replace(scheme: 'ws', path: 'ws');
+        }
+        final service = await vmServiceConnectUri(serviceUri.toString());
+        final otherService = await vmServiceConnectUri(serviceUri.toString());
+
+        IsolateRef isolate;
+        while (true) {
+          final vm = await service.getVM();
+          if (vm.isolates!.isNotEmpty) {
+            isolate = vm.isolates!.first;
+            try {
+              isolate = await service.getIsolate(isolate.id!);
+              if ((isolate as Isolate).runnable!) {
+                break;
+              }
+            } on SentinelException {
+              // ignore
+            }
+          }
+          await Future.delayed(const Duration(seconds: 1));
+        }
+        expect(isolate, isNotNull);
+
+        final expectedUserTags = <String>{};
+
+        Future<void> listenForSamples() {
+          late StreamSubscription sub;
+          final completer = Completer<void>();
+          int i = 0;
+          sub = service.onProfilerEvent.listen(
+            (event) async {
+              if (event.kind == EventKind.kCpuSamples &&
+                  event.isolate!.id! == isolate.id!) {
+                expect(expectedUserTags.isNotEmpty, true);
+                ++i;
+                if (i > 3) {
+                  if (!completer.isCompleted) {
+                    await sub.cancel();
+                    completer.complete();
+                  }
+                  return;
+                }
+                expect(event.cpuSamples, isNotNull);
+                final sampleCount = event.cpuSamples!.samples!
+                    .where((e) => expectedUserTags.contains(e.userTag))
+                    .length;
+                expect(sampleCount, event.cpuSamples!.samples!.length);
+              }
+            },
+          );
+          if (expectedUserTags.isEmpty) {
+            return Future.delayed(const Duration(seconds: 2)).then(
+              (_) async => await sub.cancel(),
+            );
+          }
+          return completer.future;
+        }
+
+        await service.streamListen(EventStreams.kProfiler);
+        Future<void> subscription = listenForSamples();
+        await service.resume(isolate.id!);
+        await subscription;
+        await service.pause(isolate.id!);
+
+        expectedUserTags.add('Testing');
+        await service.streamCpuSamplesWithUserTag(expectedUserTags.toList());
+        subscription = listenForSamples();
+        await service.resume(isolate.id!);
+        await subscription;
+        await service.pause(isolate.id!);
+
+        expectedUserTags.add('Baz');
+        await service.streamCpuSamplesWithUserTag(expectedUserTags.toList());
+        subscription = listenForSamples();
+        await service.resume(isolate.id!);
+        await subscription;
+        await service.pause(isolate.id!);
+
+        expectedUserTags.clear();
+        await service.streamCpuSamplesWithUserTag(expectedUserTags.toList());
+        subscription = listenForSamples();
+        await service.resume(isolate.id!);
+        await subscription;
+
+        await service.dispose();
+        await otherService.dispose();
+      },
+      timeout: Timeout.none,
+    );
+  }
+
+  declareTest(true);
+  declareTest(false);
+}
diff --git a/pkg/dds/test/get_cached_cpu_samples_script.dart b/pkg/dds/test/get_cached_cpu_samples_script.dart
index 5949574..78bd9fd 100644
--- a/pkg/dds/test/get_cached_cpu_samples_script.dart
+++ b/pkg/dds/test/get_cached_cpu_samples_script.dart
@@ -12,10 +12,14 @@
 }
 
 void main() {
-  UserTag('Testing').makeCurrent();
+  final tag = UserTag('Testing')..makeCurrent();
+  final tag2 = UserTag('Baz');
   int i = 5;
   while (true) {
+    tag.makeCurrent();
     ++i;
     fib(i);
+    tag2.makeCurrent();
+    fib(i);
   }
 }
diff --git a/pkg/dds/test/get_cached_cpu_samples_test.dart b/pkg/dds/test/get_cached_cpu_samples_test.dart
index d8e900e..ae25095 100644
--- a/pkg/dds/test/get_cached_cpu_samples_test.dart
+++ b/pkg/dds/test/get_cached_cpu_samples_test.dart
@@ -74,6 +74,7 @@
       );
       expect(dds.isRunning, true);
       final service = await vmServiceConnectUri(dds.wsUri.toString());
+      final otherService = await vmServiceConnectUri(dds.wsUri.toString());
 
       // Ensure we're caching results for samples under the 'Testing' UserTag.
       final availableCaches = await service.getAvailableCachedCpuSamples();
@@ -85,13 +86,18 @@
         final vm = await service.getVM();
         if (vm.isolates!.isNotEmpty) {
           isolate = vm.isolates!.first;
-          isolate = await service.getIsolate(isolate.id!);
-          if ((isolate as Isolate).runnable!) {
-            break;
+          try {
+            isolate = await service.getIsolate(isolate.id!);
+            if ((isolate as Isolate).runnable!) {
+              break;
+            }
+          } on SentinelException {
+            // ignore
           }
         }
         await Future.delayed(const Duration(seconds: 1));
       }
+      expect(isolate, isNotNull);
 
       final completer = Completer<void>();
       int i = 0;
@@ -117,9 +123,11 @@
                 // Ensure the number of CPU samples in the CpuSample event is
                 // is consistent with the number of samples in the cache.
                 expect(event.cpuSamples, isNotNull);
-                count += event.cpuSamples!.samples!
+                final sampleCount = event.cpuSamples!.samples!
                     .where((e) => e.userTag == kUserTag)
                     .length;
+                expect(sampleCount, event.cpuSamples!.samples!.length);
+                count += sampleCount;
                 final cache = await service.getCachedCpuSamples(
                   isolate.id!,
                   availableCaches.cacheNames.first,
@@ -134,6 +142,11 @@
         },
       );
       await service.streamListen(EventStreams.kProfiler);
+      await service.streamCpuSamplesWithUserTag(['Testing']);
+      // Have another client register for samples from another UserTag. The
+      // main client should not see any samples with the 'Baz' tag.
+      await otherService.streamListen(EventStreams.kProfiler);
+      await otherService.streamCpuSamplesWithUserTag(['Testing', 'Baz']);
       await service.resume(isolate.id!);
       await completer.future;
     },
diff --git a/pkg/dev_compiler/lib/src/compiler/js_typerep.dart b/pkg/dev_compiler/lib/src/compiler/js_typerep.dart
index c1291a3..e0d73cb 100644
--- a/pkg/dev_compiler/lib/src/compiler/js_typerep.dart
+++ b/pkg/dev_compiler/lib/src/compiler/js_typerep.dart
@@ -1,7 +1,8 @@
+// Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 /// An abstraction of the JS types
-
-// @dart = 2.9
-
 abstract class JSType {
   const JSType();
 
@@ -20,7 +21,7 @@
   bool get isFalsey;
 
   /// The JS `typeof` value, if unambiguous.
-  String get primitiveTypeOf => null;
+  String? get primitiveTypeOf => null;
 
   static const jsBoolean = JSBoolean();
   static const jsNumber = JSNumber();
diff --git a/pkg/dev_compiler/lib/src/kernel/compiler.dart b/pkg/dev_compiler/lib/src/kernel/compiler.dart
index a25692d..e0efac6 100644
--- a/pkg/dev_compiler/lib/src/kernel/compiler.dart
+++ b/pkg/dev_compiler/lib/src/kernel/compiler.dart
@@ -595,7 +595,7 @@
     var node = export.node;
     if (node is Procedure && node.name.text == 'main') {
       // Don't allow redefining names from this library.
-      var name = _emitTopLevelName(export.node);
+      var name = _emitTopLevelName(node);
       moduleItems.add(js.statement(
           '#.# = #;', [emitLibraryName(library), name.selector, name]));
     }
@@ -2390,10 +2390,11 @@
   /// Unlike call sites, we always have an element available, so we can use it
   /// directly rather than computing the relevant options for [_emitMemberName].
   js_ast.Expression _declareMemberName(Member m, {bool useExtension}) {
+    var c = m.enclosingClass;
     return _emitMemberName(m.name.text,
         isStatic: m is Field ? m.isStatic : (m as Procedure).isStatic,
         useExtension:
-            useExtension ?? _extensionTypes.isNativeClass(m.enclosingClass),
+            useExtension ?? c != null && _extensionTypes.isNativeClass(c),
         member: m);
   }
 
@@ -4697,15 +4698,18 @@
   /// null-checked in sound null-safety.
   ///
   /// This is true for non-nullable native return types.
-  bool _isNullCheckableNative(Member member) =>
-      _options.soundNullSafety &&
-      member != null &&
-      member.isExternal &&
-      _extensionTypes.isNativeClass(member.enclosingClass) &&
-      member is Procedure &&
-      member.function != null &&
-      member.function.returnType.isPotentiallyNonNullable &&
-      _isWebLibrary(member.enclosingLibrary?.importUri);
+  bool _isNullCheckableNative(Member member) {
+    var c = member.enclosingClass;
+    return _options.soundNullSafety &&
+        member != null &&
+        member.isExternal &&
+        c != null &&
+        _extensionTypes.isNativeClass(c) &&
+        member is Procedure &&
+        member.function != null &&
+        member.function.returnType.isPotentiallyNonNullable &&
+        _isWebLibrary(member.enclosingLibrary?.importUri);
+  }
 
   // TODO(jmesserly): can we encapsulate REPL name lookups and remove this?
   // _emitMemberName would be a nice place to handle it, but we don't have
diff --git a/pkg/dev_compiler/lib/src/kernel/js_interop.dart b/pkg/dev_compiler/lib/src/kernel/js_interop.dart
index 65ab098..d865154 100644
--- a/pkg/dev_compiler/lib/src/kernel/js_interop.dart
+++ b/pkg/dev_compiler/lib/src/kernel/js_interop.dart
@@ -2,15 +2,13 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// @dart = 2.9
-
 import 'package:kernel/kernel.dart';
+
 import 'kernel_helpers.dart';
 
 /// Returns true if [library] is one of the [candidates].
 /// The latter should be a list, e.g.,: ['dart:js', 'package:js'].
 bool _isLibrary(Library library, List<String> candidates) {
-  if (library == null) return false;
   var uri = library.importUri;
   var scheme = uri.scheme;
   var path = uri.pathSegments[0];
@@ -63,7 +61,7 @@
     _annotationIsFromJSLibrary('_Rest', value);
 
 // TODO(jmesserly): Move JsPeerInterface to package:js (see issue #135).
-// TODO(jacobr): The 'JS' annotation is the new, publically accessible one.
+// TODO(jacobr): The 'JS' annotation is the new, publicly accessible one.
 // The 'JsName' annotation is the old one using internally by dart2js and
 // html libraries.  These two concepts will probably merge eventually.
 bool isJSAnnotation(Expression value) =>
@@ -129,7 +127,7 @@
   if (n is Member && n.isExternal) {
     return n.enclosingLibrary.annotations.any(isPublicJSAnnotation) ||
         n.annotations.any(isPublicJSAnnotation) ||
-        (n.enclosingClass?.annotations?.any(isPublicJSAnnotation) ?? false);
+        (n.enclosingClass?.annotations.any(isPublicJSAnnotation) ?? false);
   } else if (n is Class) {
     return n.annotations.any(isPublicJSAnnotation);
   }
diff --git a/pkg/dev_compiler/lib/src/kernel/js_typerep.dart b/pkg/dev_compiler/lib/src/kernel/js_typerep.dart
index 646f17c..58297dc 100644
--- a/pkg/dev_compiler/lib/src/kernel/js_typerep.dart
+++ b/pkg/dev_compiler/lib/src/kernel/js_typerep.dart
@@ -2,12 +2,11 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// @dart = 2.9
-
 import 'package:kernel/class_hierarchy.dart';
 import 'package:kernel/core_types.dart';
 import 'package:kernel/kernel.dart';
 import 'package:kernel/type_environment.dart';
+
 import '../compiler/js_typerep.dart';
 import 'kernel_helpers.dart';
 
@@ -32,9 +31,8 @@
   @override
   JSType typeFor(DartType type) {
     while (type is TypeParameterType) {
-      type = (type as TypeParameterType).parameter.bound;
+      type = type.parameter.bound;
     }
-    if (type == null) return JSType.jsUnknown;
     assert(isKnownDartTypeImplementor(type));
 
     // Note that this should be changed if Dart gets non-nullable types
@@ -65,11 +63,12 @@
     return JSType.jsObject;
   }
 
-  /// Given a Dart type return the known implementation type, if any.
-  /// Given `bool`, `String`, or `num`/`int`/`double`,
-  /// returns the corresponding class in `dart:_interceptors`:
-  /// `JSBool`, `JSString`, and `JSNumber` respectively, otherwise null.
-  Class getImplementationClass(DartType t) {
+  /// Returns the known implementation type for [t], if any.
+  ///
+  /// Given `bool`, `String`, or `num`/`int`/`double`, returns the corresponding
+  /// class in `dart:_interceptors`: `JSBool`, `JSString`, and `JSNumber`
+  /// respectively, otherwise null.
+  Class? getImplementationClass(DartType t) {
     var rep = typeFor(t);
     // Number, String, and Bool are final
     if (rep == JSType.jsNumber) return _jsNumber;
diff --git a/pkg/dev_compiler/lib/src/kernel/module_symbols.dart b/pkg/dev_compiler/lib/src/kernel/module_symbols.dart
index 73f14cf..8e90b06 100644
--- a/pkg/dev_compiler/lib/src/kernel/module_symbols.dart
+++ b/pkg/dev_compiler/lib/src/kernel/module_symbols.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// @dart = 2.9
-
 // Dart debug symbol information stored by DDC.
 //
 // The data format below stores descriptions of dart code objects and their
@@ -90,94 +88,110 @@
   static const SemanticVersion current = SemanticVersion(0, 0, 1);
 
   /// Semantic version of the format.
-  String version;
+  final String version;
 
   /// Module name as used in the module metadata
-  String moduleName;
+  final String moduleName;
 
   /// All dart libraries included in the module.
   ///
   /// Note here and below that imported elements are not included in
   /// the current module but can be referenced by their ids.
-  List<LibrarySymbol> libraries;
+  final List<LibrarySymbol> libraries;
 
   /// All dart scripts included in the module.
-  List<Script> scripts;
+  final List<Script> scripts;
 
   /// All dart classes included in the module.
-  List<ClassSymbol> classes;
+  final List<ClassSymbol> classes;
 
   /// All dart function types included in the module.
-  List<FunctionTypeSymbol> functionTypes;
+  final List<FunctionTypeSymbol> functionTypes;
 
   /// All dart function types included in the module.
-  List<FunctionSymbol> functions;
+  final List<FunctionSymbol> functions;
 
   /// All dart scopes included in the module.
   ///
   /// Does not include scopes listed in other fields,
   /// such as libraries, classes, and functions.
-  List<ScopeSymbol> scopes;
+  final List<ScopeSymbol> scopes;
 
-  /// All dart variables included in the module.
+  /// All Dart variables included in the module.
   List<VariableSymbol> variables;
+
   ModuleSymbols({
-    this.version,
-    this.moduleName,
-    this.libraries,
-    this.scripts,
-    this.classes,
-    this.functionTypes,
-    this.functions,
-    this.scopes,
-    this.variables,
-  });
-  ModuleSymbols.fromJson(Map<String, dynamic> json) {
-    version = _createValue(json['version'], ifNull: current.version);
+    String? version,
+    required this.moduleName,
+    List<LibrarySymbol>? libraries,
+    List<Script>? scripts,
+    List<ClassSymbol>? classes,
+    List<FunctionTypeSymbol>? functionTypes,
+    List<FunctionSymbol>? functions,
+    List<ScopeSymbol>? scopes,
+    List<VariableSymbol>? variables,
+  })  : version = version ??= current.version,
+        libraries = libraries ?? [],
+        scripts = scripts ?? [],
+        classes = classes ?? [],
+        functionTypes = functionTypes ?? [],
+        functions = functions ?? [],
+        scopes = scopes ?? [],
+        variables = variables ?? [];
+
+  ModuleSymbols.fromJson(Map<String, dynamic> json)
+      : version = _readAndValidateVersionFromJson(json['version']),
+        moduleName = _createValue(json['moduleName']),
+        libraries =
+            _createObjectList(json['libraries'], LibrarySymbol.fromJson),
+        scripts = _createObjectList(json['scripts'], Script.fromJson),
+        classes = _createObjectList(json['classes'], ClassSymbol.fromJson),
+        functionTypes = _createObjectList(
+            json['functionTypes'], FunctionTypeSymbol.fromJson),
+        functions =
+            _createObjectList(json['functions'], FunctionSymbol.fromJson),
+        scopes = _createObjectList(json['scopes'], ScopeSymbol.fromJson),
+        variables =
+            _createObjectList(json['variables'], VariableSymbol.fromJson);
+
+  @override
+  Map<String, dynamic> toJson() {
+    final json = <String, dynamic>{
+      'version': version,
+      'moduleName': moduleName,
+    };
+    _setObjectListIfNotNullOrEmpty(json, 'libraries', libraries);
+    _setObjectListIfNotNullOrEmpty(json, 'scripts', scripts);
+    _setObjectListIfNotNullOrEmpty(json, 'classes', classes);
+    _setObjectListIfNotNullOrEmpty(json, 'functionTypes', functionTypes);
+    _setObjectListIfNotNullOrEmpty(json, 'functions', functions);
+    _setObjectListIfNotNullOrEmpty(json, 'scopes', scopes);
+    _setObjectListIfNotNullOrEmpty(json, 'variables', variables);
+    return json;
+  }
+
+  static String _readAndValidateVersionFromJson(dynamic json) {
+    if (json == null) return current.version;
+    var version = _createValue<String>(json);
     if (!current.isCompatibleWith(version)) {
       throw Exception('Unsupported version $version. '
           'Current version: ${current.version}');
     }
-    moduleName = _createValue(json['moduleName']);
-    libraries = _createObjectList(
-        json['libraries'], (json) => LibrarySymbol.fromJson(json));
-    scripts =
-        _createObjectList(json['scripts'], (json) => Script.fromJson(json));
-    classes = _createObjectList(
-        json['classes'], (json) => ClassSymbol.fromJson(json));
-    functionTypes = _createObjectList(
-        json['functionTypes'], (json) => FunctionTypeSymbol.fromJson(json));
-    functions = _createObjectList(
-        json['functions'], (json) => FunctionSymbol.fromJson(json));
-    scopes =
-        _createObjectList(json['scopes'], (json) => ScopeSymbol.fromJson(json));
-    variables = _createObjectList(
-        json['variables'], (json) => VariableSymbol.fromJson(json));
-  }
-  @override
-  Map<String, dynamic> toJson() {
-    final json = <String, dynamic>{};
-    _setValueIfNotNull(json, 'version', version);
-    _setValueIfNotNull(json, 'moduleName', moduleName);
-    _setObjectListIfNotNull(json, 'libraries', libraries);
-    _setObjectListIfNotNull(json, 'scripts', scripts);
-    _setObjectListIfNotNull(json, 'classes', classes);
-    _setObjectListIfNotNull(json, 'functionTypes', functionTypes);
-    _setObjectListIfNotNull(json, 'functions', functions);
-    _setObjectListIfNotNull(json, 'scopes', scopes);
-    _setObjectListIfNotNull(json, 'variables', variables);
-    return json;
+    return version;
   }
 }
 
 class Symbol implements SymbolTableElement {
   /// Local id (such as JS name) for the symbol.
   ///
-  /// Used to map from dart objects to JS objects inside a scope.
-  String localId;
+  /// Used to map from Dart objects to JS objects inside a scope.
+  final String localId;
 
   /// Enclosing scope of the symbol.
-  String scopeId;
+  final String? scopeId;
+
+  /// Source location of the symbol.
+  final SourceLocation? location;
 
   /// Unique Id, shared with JS representation (if any).
   ///
@@ -186,20 +200,20 @@
   /// Where scope refers to a Library, Class, Function, or Scope.
   String get id => scopeId == null ? localId : '$scopeId|$localId';
 
-  /// Source location of the symbol.
-  SourceLocation location;
-  Symbol({this.localId, this.scopeId, this.location});
-  Symbol.fromJson(Map<String, dynamic> json) {
-    localId = _createValue(json['localId']);
-    scopeId = _createValue(json['scopeId']);
-    location = _createObject(
-        json['location'], (json) => SourceLocation.fromJson(json));
-  }
+  Symbol({required this.localId, this.scopeId, this.location});
+
+  Symbol.fromJson(Map<String, dynamic> json)
+      : localId = _createValue(json['localId']),
+        scopeId = _createValue(json['scopeId']),
+        location =
+            _createNullableObject(json['location'], SourceLocation.fromJson);
+
   @override
   Map<String, dynamic> toJson() {
-    final json = <String, dynamic>{};
-    _setValueIfNotNull(json, 'localId', localId);
-    _setValueIfNotNull(json, 'scopeId', scopeId);
+    final json = <String, dynamic>{
+      'localId': localId,
+      if (scopeId != null) 'scopeId': scopeId,
+    };
     _setObjectIfNotNull(json, 'location', location);
     return json;
   }
@@ -210,6 +224,7 @@
 }
 
 enum VariableSymbolKind { global, local, property, field, formal, none }
+
 VariableSymbolKind parseVariableSymbolKind(String value) {
   return VariableSymbolKind.values.singleWhere((e) => value == '$e',
       orElse: () {
@@ -218,189 +233,210 @@
 }
 
 class VariableSymbol extends Symbol {
-  /// Variable name
-  String name;
+  /// Name of the variable in Dart source code.
+  final String name;
 
   /// Symbol kind.
-  VariableSymbolKind kind;
+  final VariableSymbolKind kind;
 
-  /// The declared type of this symbol.
-  String typeId;
+  /// The declared type of this symbol in Dart source code.
+  // TODO(nshahan) Only nullable until we design how to identify types from
+  // other modules.
+  final String? typeId;
 
-  /// Is this variable const?
-  bool isConst;
+  /// True if this variable const.
+  final bool isConst;
 
-  /// Is this variable final?
-  bool isFinal;
+  /// True if this variable final.
+  final bool isFinal;
 
-  /// Is this variable static?
-  bool isStatic;
+  /// True if this variable static.
+  final bool isStatic;
 
   /// Property getter, if any.
-  String getterId;
+  final String? getterId;
 
   /// Property setter, if any.
-  String setterId;
+  final String? setterId;
+
   VariableSymbol({
-    this.name,
-    this.kind,
-    this.isConst,
-    this.isFinal,
-    this.isStatic,
-    this.typeId,
-    String localId,
-    String scopeId,
-    SourceLocation location,
-  }) : super(localId: localId, scopeId: scopeId, location: location);
-  VariableSymbol.fromJson(Map<String, dynamic> json) : super.fromJson(json) {
-    name = _createValue(json['name']);
-    kind = _createValue(json['kind'],
-        parse: parseVariableSymbolKind, ifNull: VariableSymbolKind.none);
-    isConst = _createValue(json['isConst']);
-    isFinal = _createValue(json['isFinal']);
-    isStatic = _createValue(json['isStatic']);
-    typeId = _createValue(json['typeId']);
-    setterId = _createValue(json['setterId']);
-    getterId = _createValue(json['getterId']);
-  }
+    required this.name,
+    required this.kind,
+    required this.typeId,
+    bool? isConst,
+    bool? isFinal,
+    bool? isStatic,
+    this.getterId,
+    this.setterId,
+    required String localId,
+    required String scopeId,
+    required SourceLocation location,
+  })  : isConst = isConst ?? false,
+        isFinal = isFinal ?? false,
+        isStatic = isStatic ?? false,
+        super(localId: localId, scopeId: scopeId, location: location);
+
+  VariableSymbol.fromJson(Map<String, dynamic> json)
+      : name = _createValue(json['name']),
+        kind = _createValue(json['kind'],
+            parse: parseVariableSymbolKind, ifNull: VariableSymbolKind.none),
+        typeId = _createValue(json['typeId']),
+        isConst = _createValue(json['isConst']),
+        isFinal = _createValue(json['isFinal']),
+        isStatic = _createValue(json['isStatic']),
+        getterId = _createValue(json['getterId']),
+        setterId = _createValue(json['setterId']),
+        super.fromJson(json);
+
   @override
-  Map<String, dynamic> toJson() {
-    final json = super.toJson();
-    _setValueIfNotNull(json, 'name', name);
-    _setValueIfNotNull(json, 'kind', kind.toString());
-    _setValueIfNotNull(json, 'isConst', isConst);
-    _setValueIfNotNull(json, 'isFinal', isFinal);
-    _setValueIfNotNull(json, 'isStatic', isStatic);
-    _setValueIfNotNull(json, 'typeId', typeId);
-    _setValueIfNotNull(json, 'setterId', setterId);
-    _setValueIfNotNull(json, 'getterId', getterId);
-    return json;
-  }
+  Map<String, dynamic> toJson() => {
+        ...super.toJson(),
+        'name': name,
+        'kind': kind.toString(),
+        if (typeId != null) 'typeId': typeId,
+        'isConst': isConst,
+        'isFinal': isFinal,
+        'isStatic': isStatic,
+        if (getterId != null) 'getterId': getterId,
+        if (setterId != null) 'setterId': setterId,
+      };
 }
 
 class ClassSymbol extends ScopeSymbol implements TypeSymbol {
-  /// The name of this class.
-  String name;
+  /// The name of this class in Dart source code.
+  final String name;
 
-  /// Is this an abstract class?
-  bool isAbstract;
+  /// True if this class is abstract.
+  final bool isAbstract;
 
-  /// Is this a const class?
-  bool isConst;
+  /// True if this class is const.
+  final bool isConst;
 
   /// The superclass of this class, if any.
-  String superClassId;
+  final String? superClassId;
 
   /// A list of interface types for this class.
-  List<String> interfaceIds;
+  final List<String> interfaceIds;
 
-  /// Mapping of type parameter dart names to JS names.
-  Map<String, String> typeParameters;
+  /// Mapping of type parameter Dart names to JS names.
+  final Map<String, String> typeParameters;
 
   /// Library that contains this class.
-  String get libraryId => scopeId;
+  String get libraryId => scopeId!;
 
   /// Fields in this class.
   ///
   /// Including static fields, methods, and properties.
   List<String> get fieldIds => variableIds;
 
-  /// A list of functions in this class.
+  /// Functions in this class.
   ///
   /// Includes all static functions, methods, getters,
   /// and setters in the current class.
   ///
   /// Does not include functions from superclasses.
   List<String> get functionIds => scopeIds;
+
   ClassSymbol({
-    this.name,
-    this.isAbstract,
-    this.isConst,
+    required this.name,
+    bool? isAbstract,
+    bool? isConst,
     this.superClassId,
-    this.interfaceIds,
-    this.typeParameters,
-    String localId,
-    String scopeId,
-    SourceLocation location,
-    List<String> variableIds,
-    List<String> scopeIds,
-  }) : super(
+    List<String>? interfaceIds,
+    Map<String, String>? typeParameters,
+    required String localId,
+    required String scopeId,
+    required SourceLocation location,
+    List<String>? variableIds,
+    List<String>? scopeIds,
+  })  : isAbstract = isAbstract ?? false,
+        isConst = isConst ?? false,
+        interfaceIds = interfaceIds ?? [],
+        typeParameters = typeParameters ?? {},
+        super(
             localId: localId,
             scopeId: scopeId,
             variableIds: variableIds,
             scopeIds: scopeIds,
             location: location);
-  ClassSymbol.fromJson(Map<String, dynamic> json) : super.fromJson(json) {
-    name = _createValue(json['name']);
-    isAbstract = _createValue(json['isAbstract']);
-    isConst = _createValue(json['isConst']);
-    superClassId = _createValue(json['superClassId']);
-    interfaceIds = _createValueList(json['interfaceIds']);
-    typeParameters = _createValueMap(json['typeParameters']);
-  }
+
+  ClassSymbol.fromJson(Map<String, dynamic> json)
+      : name = _createValue(json['name']),
+        isAbstract = _createValue(json['isAbstract']),
+        isConst = _createValue(json['isConst']),
+        superClassId = _createValue(json['superClassId']),
+        interfaceIds = _createValueList(json['interfaceIds']),
+        typeParameters = _createValueMap(json['typeParameters']),
+        super.fromJson(json);
+
   @override
-  Map<String, dynamic> toJson() {
-    final json = super.toJson();
-    _setValueIfNotNull(json, 'name', name);
-    _setValueIfNotNull(json, 'isAbstract', isAbstract);
-    _setValueIfNotNull(json, 'isConst', isConst);
-    _setValueIfNotNull(json, 'superClassId', superClassId);
-    _setValueIfNotNull(json, 'interfaceIds', interfaceIds);
-    _setValueIfNotNull(json, 'typeParameters', typeParameters);
-    return json;
-  }
+  Map<String, dynamic> toJson() => {
+        ...super.toJson(),
+        'name': name,
+        'isAbstract': isAbstract,
+        'isConst': isConst,
+        if (superClassId != null) 'superClassId': superClassId,
+        if (interfaceIds.isNotEmpty) 'interfaceIds': interfaceIds,
+        if (typeParameters.isNotEmpty) 'typeParameters': typeParameters,
+      };
 }
 
 class FunctionTypeSymbol extends Symbol implements TypeSymbol {
   /// Mapping of dart type parameter names to JS names.
-  Map<String, String> typeParameters;
+  final Map<String, String> typeParameters;
 
   /// Types for positional parameters for this function.
-  List<String> parameterTypeIds;
+  final List<String> parameterTypeIds;
 
   /// Types for optional positional parameters for this function.
-  List<String> optionalParameterTypeIds;
+  final List<String> optionalParameterTypeIds;
 
   /// Names and types for named parameters for this function.
-  Map<String, String> namedParameterTypeIds;
+  final Map<String, String> namedParameterTypeIds;
 
-  /// A return type for this function.
-  String returnTypeId;
+  /// The return type for this function.
+  final String returnTypeId;
+
   FunctionTypeSymbol({
-    this.typeParameters,
-    this.parameterTypeIds,
-    this.optionalParameterTypeIds,
-    this.namedParameterTypeIds,
-    this.returnTypeId,
-    String localId,
-    String scopeId,
-    SourceLocation location,
-  }) : super(localId: localId, scopeId: scopeId, location: location);
+    Map<String, String>? typeParameters,
+    List<String>? parameterTypeIds,
+    List<String>? optionalParameterTypeIds,
+    Map<String, String>? namedParameterTypeIds,
+    required this.returnTypeId,
+    required String localId,
+    required String scopeId,
+    required SourceLocation location,
+  })  : typeParameters = typeParameters ?? {},
+        parameterTypeIds = parameterTypeIds ?? [],
+        optionalParameterTypeIds = optionalParameterTypeIds ?? [],
+        namedParameterTypeIds = namedParameterTypeIds ?? {},
+        super(localId: localId, scopeId: scopeId, location: location);
+
   FunctionTypeSymbol.fromJson(Map<String, dynamic> json)
-      : super.fromJson(json) {
-    parameterTypeIds = _createValueList(json['parameterTypeIds']);
-    optionalParameterTypeIds =
-        _createValueList(json['optionalParameterTypeIds']);
-    typeParameters = _createValueMap(json['typeParameters']);
-    namedParameterTypeIds = _createValueMap(json['namedParameterTypeIds']);
-    returnTypeId = _createValue(json['returnTypeId']);
-  }
+      : parameterTypeIds = _createValueList(json['parameterTypeIds']),
+        optionalParameterTypeIds =
+            _createValueList(json['optionalParameterTypeIds']),
+        typeParameters = _createValueMap(json['typeParameters']),
+        namedParameterTypeIds = _createValueMap(json['namedParameterTypeIds']),
+        returnTypeId = _createValue(json['returnTypeId']),
+        super.fromJson(json);
+
   @override
-  Map<String, dynamic> toJson() {
-    final json = super.toJson();
-    _setValueIfNotNull(json, 'typeParameters', typeParameters);
-    _setValueIfNotNull(json, 'parameterTypeIds', parameterTypeIds);
-    _setValueIfNotNull(
-        json, 'optionalParameterTypeIds', optionalParameterTypeIds);
-    _setValueIfNotNull(json, 'namedParameterTypeIds', namedParameterTypeIds);
-    _setValueIfNotNull(json, 'returnTypeId', returnTypeId);
-    return json;
-  }
+  Map<String, dynamic> toJson() => {
+        ...super.toJson(),
+        if (typeParameters.isNotEmpty) 'typeParameters': typeParameters,
+        if (parameterTypeIds.isNotEmpty) 'parameterTypeIds': parameterTypeIds,
+        if (optionalParameterTypeIds.isNotEmpty)
+          'optionalParameterTypeIds': optionalParameterTypeIds,
+        if (namedParameterTypeIds.isNotEmpty)
+          'namedParameterTypeIds': namedParameterTypeIds,
+        'returnTypeId': returnTypeId,
+      };
 }
 
 class FunctionSymbol extends ScopeSymbol {
   /// The name of this function.
-  String name;
+  final String name;
 
   /// Unique Id, shared with JS representation (if any).
   ///
@@ -410,232 +446,238 @@
   /// Where scope refers to a Library, Class, Function, or Scope.
   /// String id;
   /// Declared type of this function.
-  String typeId;
+  // TODO(nshahan) Only nullable because unused at this time.
+  final String? typeId;
 
-  /// Is this function static?
-  bool isStatic;
+  /// True if this function is static.
+  final bool isStatic;
 
-  /// Is this function const?
-  bool isConst;
+  /// True if this function is const.
+  final bool isConst;
+
   FunctionSymbol({
-    this.name,
-    this.typeId,
-    this.isStatic,
-    this.isConst,
-    String localId,
-    String scopeId,
-    List<String> variableIds,
-    List<String> scopeIds,
-    SourceLocation location,
-  }) : super(
+    required this.name,
+    required this.typeId,
+    bool? isStatic,
+    bool? isConst,
+    required String localId,
+    required String scopeId,
+    List<String>? variableIds,
+    List<String>? scopeIds,
+    required SourceLocation location,
+  })  : isStatic = isStatic ?? false,
+        isConst = isConst ?? false,
+        super(
           localId: localId,
           scopeId: scopeId,
           variableIds: variableIds,
           scopeIds: scopeIds,
           location: location,
         );
-  FunctionSymbol.fromJson(Map<String, dynamic> json) : super.fromJson(json) {
-    name = _createValue(json['name']);
-    typeId = _createValue(json['typeId']);
-    isStatic = _createValue(json['isStatic']);
-    isConst = _createValue(json['isConst']);
-  }
+
+  FunctionSymbol.fromJson(Map<String, dynamic> json)
+      : name = _createValue(json['name']),
+        typeId = _createValue(json['typeId']),
+        isStatic = _createValue(json['isStatic']),
+        isConst = _createValue(json['isConst']),
+        super.fromJson(json);
+
   @override
-  Map<String, dynamic> toJson() {
-    final json = super.toJson();
-    _setValueIfNotNull(json, 'name', name);
-    _setValueIfNotNull(json, 'typeId', typeId);
-    _setValueIfNotNull(json, 'isStatic', isStatic);
-    _setValueIfNotNull(json, 'isConst', isConst);
-    return json;
-  }
+  Map<String, dynamic> toJson() => {
+        ...super.toJson(),
+        'name': name,
+        if (typeId != null) 'typeId': typeId,
+        'isStatic': isStatic,
+        'isConst': isConst,
+      };
 }
 
 class LibrarySymbol extends ScopeSymbol {
   /// The name of this library.
-  String name;
+  final String name;
 
-  /// Unique Id.
-  ///
-  /// Currently the debugger can find the library uri from JS location
-  /// using source maps and module metadata.
-  ///
-  /// Can be same as library uri.
-  /// String id;
   /// The uri of this library.
-  String uri;
+  final String uri;
 
   /// A list of the imports for this library.
-  List<LibrarySymbolDependency> dependencies;
+  final List<LibrarySymbolDependency> dependencies;
 
   /// A list of the scripts which constitute this library.
-  List<String> scriptIds;
+  final List<String> scriptIds;
+
   LibrarySymbol({
-    this.name,
-    this.uri,
-    this.dependencies,
-    this.scriptIds,
-    List<String> variableIds,
-    List<String> scopeIds,
-  }) : super(
+    String? name,
+    required this.uri,
+    List<LibrarySymbolDependency>? dependencies,
+    required this.scriptIds,
+    List<String>? variableIds,
+    List<String>? scopeIds,
+  })  : name = name ?? '',
+        dependencies = dependencies ?? [],
+        super(
           localId: uri,
           variableIds: variableIds,
           scopeIds: scopeIds,
         );
 
-  LibrarySymbol.fromJson(Map<String, dynamic> json) : super.fromJson(json) {
-    name = _createValue(json['name'], ifNull: '');
-    uri = _createValue(json['uri']);
-    scriptIds = _createValueList(json['scriptIds']);
-    dependencies = _createObjectList(
-        json['dependencies'], (json) => LibrarySymbolDependency.fromJson(json));
-  }
+  LibrarySymbol.fromJson(Map<String, dynamic> json)
+      : name = _createValue(json['name'], ifNull: ''),
+        uri = _createValue(json['uri']),
+        scriptIds = _createValueList(json['scriptIds']),
+        dependencies = _createObjectList(
+            json['dependencies'], LibrarySymbolDependency.fromJson),
+        super.fromJson(json);
+
   @override
   Map<String, dynamic> toJson() {
-    final json = super.toJson();
-    _setValueIfNotNull(json, 'name', name);
-    _setValueIfNotNull(json, 'uri', uri);
-    _setValueIfNotNull(json, 'scriptIds', scriptIds);
-    _setObjectListIfNotNull(json, 'dependencies', dependencies);
+    final json = {
+      ...super.toJson(),
+      if (name.isNotEmpty) 'name': name,
+      'uri': uri,
+      if (scriptIds.isNotEmpty) 'scriptIds': scriptIds,
+    };
+    _setObjectListIfNotNullOrEmpty(json, 'dependencies', dependencies);
     return json;
   }
 }
 
 class LibrarySymbolDependency implements SymbolTableElement {
-  /// Is this dependency an import (rather than an export)?
-  bool isImport;
+  /// True if this dependency an import, false if an an export.
+  final bool isImport;
 
-  /// Is this dependency deferred?
-  bool isDeferred;
+  /// True if this dependency is deferred.
+  final bool isDeferred;
 
   /// The prefix of an 'as' import, or null.
-  String prefix;
+  final String? prefix;
 
   /// The library being imported or exported.
-  String targetId;
+  final String targetId;
+
   LibrarySymbolDependency({
-    this.isImport,
-    this.isDeferred,
+    required this.isImport,
+    bool? isDeferred,
     this.prefix,
-    this.targetId,
-  });
-  LibrarySymbolDependency.fromJson(Map<String, dynamic> json) {
-    isImport = _createValue(json['isImport']);
-    isDeferred = _createValue(json['isDeferred']);
-    prefix = _createValue(json['prefix']);
-    targetId = _createValue(json['targetId']);
-  }
+    required this.targetId,
+  }) : isDeferred = isDeferred ?? false;
+
+  LibrarySymbolDependency.fromJson(Map<String, dynamic> json)
+      : isImport = _createValue(json['isImport']),
+        isDeferred = _createValue(json['isDeferred']),
+        prefix = _createValue(json['prefix']),
+        targetId = _createValue(json['targetId']);
+
   @override
-  Map<String, dynamic> toJson() {
-    final json = <String, dynamic>{};
-    _setValueIfNotNull(json, 'isImport', isImport);
-    _setValueIfNotNull(json, 'isDeferred', isDeferred);
-    _setValueIfNotNull(json, 'prefix', prefix);
-    _setValueIfNotNull(json, 'targetId', targetId);
-    return json;
-  }
+  Map<String, dynamic> toJson() => {
+        'isImport': isImport,
+        'isDeferred': isDeferred,
+        if (prefix != null) 'prefix': prefix,
+        'targetId': targetId,
+      };
 }
 
 class Script implements SymbolTableElement {
   /// The uri from which this script was loaded.
-  String uri;
+  final String uri;
 
   /// Unique Id.
   ///
   /// This can be just an integer. The mapping from JS to dart script
   /// happens using the source map. The id is only used for references
   /// in other elements.
-  String localId;
+  final String localId;
 
-  String libraryId;
+  final String libraryId;
 
   String get id => '$libraryId|$localId';
 
   Script({
-    this.uri,
-    this.localId,
-    this.libraryId,
+    required this.uri,
+    required this.localId,
+    required this.libraryId,
   });
-  Script.fromJson(Map<String, dynamic> json) {
-    uri = _createValue(json['uri']);
-    localId = _createValue(json['localId']);
-    libraryId = _createValue(json['libraryId']);
-  }
-  @override
-  Map<String, dynamic> toJson() {
-    final json = <String, dynamic>{};
-    _setValueIfNotNull(json, 'uri', uri);
-    _setValueIfNotNull(json, 'localId', localId);
-    _setValueIfNotNull(json, 'libraryId', libraryId);
 
-    return json;
-  }
+  Script.fromJson(Map<String, dynamic> json)
+      : uri = _createValue(json['uri']),
+        localId = _createValue(json['localId']),
+        libraryId = _createValue(json['libraryId']);
+
+  @override
+  Map<String, dynamic> toJson() => {
+        'uri': uri,
+        'localId': localId,
+        'libraryId': libraryId,
+      };
 }
 
 class ScopeSymbol extends Symbol {
   /// A list of the top-level variables in this scope.
-  List<String> variableIds;
+  final List<String> variableIds;
 
   /// Enclosed scopes.
   ///
   /// Includes all top classes, functions, inner scopes.
-  List<String> scopeIds;
+  final List<String> scopeIds;
+
   ScopeSymbol({
-    this.variableIds,
-    this.scopeIds,
-    String localId,
-    String scopeId,
-    SourceLocation location,
-  }) : super(
+    List<String>? variableIds,
+    List<String>? scopeIds,
+    required String localId,
+    String? scopeId,
+    SourceLocation? location,
+  })  : variableIds = variableIds ?? [],
+        scopeIds = scopeIds ?? [],
+        super(
           localId: localId,
           scopeId: scopeId,
           location: location,
         );
-  ScopeSymbol.fromJson(Map<String, dynamic> json) : super.fromJson(json) {
-    variableIds = _createValueList(json['variableIds']);
-    scopeIds = _createValueList(json['scopeIds']);
-  }
+
+  ScopeSymbol.fromJson(Map<String, dynamic> json)
+      : variableIds = _createValueList(json['variableIds']),
+        scopeIds = _createValueList(json['scopeIds']),
+        super.fromJson(json);
+
   @override
-  Map<String, dynamic> toJson() {
-    final json = super.toJson();
-    _setValueIfNotNull(json, 'variableIds', variableIds);
-    _setValueIfNotNull(json, 'scopeIds', scopeIds);
-    return json;
-  }
+  Map<String, dynamic> toJson() => {
+        ...super.toJson(),
+        if (variableIds.isNotEmpty) 'variableIds': variableIds,
+        if (scopeIds.isNotEmpty) 'scopeIds': scopeIds,
+      };
 }
 
 class SourceLocation implements SymbolTableElement {
   /// The script containing the source location.
-  String scriptId;
+  final String scriptId;
 
   /// The first token of the location.
-  int tokenPos;
+  final int tokenPos;
 
   /// The last token of the location if this is a range.
-  int endTokenPos;
+  final int? endTokenPos;
+
   SourceLocation({
-    this.scriptId,
-    this.tokenPos,
+    required this.scriptId,
+    required this.tokenPos,
     this.endTokenPos,
   });
-  SourceLocation.fromJson(Map<String, dynamic> json) {
-    scriptId = _createValue(json['scriptId']);
-    tokenPos = _createValue(json['tokenPos']);
-    endTokenPos = _createValue(json['endTokenPos']);
-  }
+
+  SourceLocation.fromJson(Map<String, dynamic> json)
+      : scriptId = _createValue(json['scriptId']),
+        tokenPos = _createValue(json['tokenPos']),
+        endTokenPos = _createValue(json['endTokenPos']);
+
   @override
-  Map<String, dynamic> toJson() {
-    final json = <String, dynamic>{};
-    _setValueIfNotNull(json, 'scriptId', scriptId);
-    _setValueIfNotNull(json, 'tokenPos', tokenPos);
-    _setValueIfNotNull(json, 'endTokenPos', endTokenPos);
-    return json;
-  }
+  Map<String, dynamic> toJson() => {
+        'scriptId': scriptId,
+        'tokenPos': tokenPos,
+        if (endTokenPos != null) 'endTokenPos': endTokenPos,
+      };
 }
 
 List<T> _createObjectList<T>(
     dynamic json, T Function(Map<String, dynamic>) creator) {
-  if (json == null) return null;
+  if (json == null) return <T>[];
   if (json is List) {
     return json.map((e) => _createObject(e, creator)).toList();
   }
@@ -643,16 +685,19 @@
 }
 
 T _createObject<T>(dynamic json, T Function(Map<String, dynamic>) creator) {
-  if (json == null) return null;
   if (json is Map<String, dynamic>) {
     return creator(json);
   }
   throw ArgumentError('Not a map: $json');
 }
 
+T? _createNullableObject<T>(
+        dynamic json, T Function(Map<String, dynamic>) creator) =>
+    json == null ? null : _createObject(json, creator);
+
 List<T> _createValueList<T>(dynamic json,
-    {T ifNull, T Function(String) parse}) {
-  if (json == null) return null;
+    {T? ifNull, T Function(String)? parse}) {
+  if (json == null) return <T>[];
   if (json is List) {
     return json
         .map((e) => _createValue<T>(e, ifNull: ifNull, parse: parse))
@@ -662,12 +707,12 @@
 }
 
 Map<String, T> _createValueMap<T>(dynamic json) {
-  if (json == null) return null;
+  if (json == null) return <String, T>{};
   return Map<String, T>.from(json as Map<String, dynamic>);
 }
 
-T _createValue<T>(dynamic json, {T ifNull, T Function(String) parse}) {
-  if (json == null) return ifNull;
+T _createValue<T>(dynamic json, {T? ifNull, T Function(String)? parse}) {
+  if (json == null && ifNull is T) return ifNull;
   if (json is T) {
     return json;
   }
@@ -677,19 +722,14 @@
   throw ArgumentError('Cannot parse $json as $T');
 }
 
-void _setObjectListIfNotNull<T extends SymbolTableElement>(
-    Map<String, dynamic> json, String key, List<T> values) {
-  if (values == null) return;
-  json[key] = values.map((e) => e?.toJson()).toList();
+void _setObjectListIfNotNullOrEmpty<T extends SymbolTableElement>(
+    Map<String, dynamic> json, String key, List<T>? values) {
+  if (values == null || values.isEmpty) return;
+  json[key] = values.map((e) => e.toJson()).toList();
 }
 
 void _setObjectIfNotNull<T extends SymbolTableElement>(
-    Map<String, dynamic> json, String key, T value) {
+    Map<String, dynamic> json, String key, T? value) {
   if (value == null) return;
-  json[key] = value?.toJson();
-}
-
-void _setValueIfNotNull<T>(Map<String, dynamic> json, String key, T value) {
-  if (value == null) return;
-  json[key] = value;
+  json[key] = value.toJson();
 }
diff --git a/pkg/dev_compiler/lib/src/kernel/module_symbols_collector.dart b/pkg/dev_compiler/lib/src/kernel/module_symbols_collector.dart
index 2b458bb..6eb1acd 100644
--- a/pkg/dev_compiler/lib/src/kernel/module_symbols_collector.dart
+++ b/pkg/dev_compiler/lib/src/kernel/module_symbols_collector.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// @dart = 2.9
-
 import 'package:front_end/src/fasta/kernel/constructor_tearoff_lowering.dart'
     show isTearOffLowering;
 import 'package:kernel/kernel.dart';
@@ -25,16 +23,7 @@
 
   ModuleSymbolsCollector(String moduleName, this._classJsNames,
       this._memberJsNames, this._procedureJsNames, this._variableJsNames)
-      : _moduleSymbols = ModuleSymbols(
-            version: ModuleSymbols.current.version,
-            moduleName: moduleName,
-            libraries: <LibrarySymbol>[],
-            scripts: <Script>[],
-            classes: <ClassSymbol>[],
-            // TODO(nshahan) functionTypes
-            functions: <FunctionSymbol>[],
-            // TODO(nshahan) scopes
-            variables: <VariableSymbol>[]);
+      : _moduleSymbols = ModuleSymbols(moduleName: moduleName);
 
   ModuleSymbols collectSymbolInfo(Component node) {
     node.accept(this);
@@ -45,7 +34,9 @@
   String _scriptId(Uri fileUri) => fileUri.toString();
 
   /// Returns the id of [type].
-  String _typeId(DartType type) =>
+  // TODO(nshahan) Only nullable until we design how to identify types from
+  // other modules.
+  String? _typeId(DartType type) =>
       // TODO(nshahan) How to handle function types or types from other modules?
       type is InterfaceType ? _classJsNames[type.classNode] : null;
 
@@ -55,15 +46,14 @@
         name: node.name.text,
         // TODO(nshahan) typeId - probably should canonicalize but keep original
         // type argument names.
+        typeId: null,
         // TODO(nshahan) Should we mark all constructors static?
         isStatic: node is Procedure ? node.isStatic : false,
         isConst: node.isConst,
-        localId: _memberJsNames[node] ?? _procedureJsNames[node],
+        localId: _memberJsNames[node] ?? _procedureJsNames[node]!,
         scopeId: _scopes.last.id,
-        variableIds: <String>[],
-        scopeIds: <String>[],
         location: SourceLocation(
-            scriptId: _scriptId(node.location.file),
+            scriptId: _scriptId(node.location!.file),
             tokenPos: node.fileOffset,
             endTokenPos: node.fileEndOffset));
 
@@ -83,22 +73,19 @@
         isConst: node.constructors.any((constructor) => constructor.isConst),
         superClassId: _classJsNames[node.superclass],
         interfaceIds: [
-          for (var type in node.implementedTypes) _classJsNames[type.classNode]
+          for (var type in node.implementedTypes) _classJsNames[type.classNode]!
         ],
         typeParameters: {
           for (var param in node.typeParameters)
             // TODO(nshahan) Value should be the JS name.
-            param.name: param.name
+            param.name!: param.name!
         },
-        localId: _classJsNames[node],
+        localId: _classJsNames[node]!,
         scopeId: _scopes.last.id,
         location: SourceLocation(
-            scriptId: _scriptId(node.location.file),
+            scriptId: _scriptId(node.location!.file),
             tokenPos: node.startFileOffset,
-            endTokenPos: node.fileEndOffset),
-        // Create empty list, they are added in visitField().
-        variableIds: <String>[],
-        scopeIds: <String>[]);
+            endTokenPos: node.fileEndOffset));
 
     _scopes.add(classSymbol);
     node.visitChildren(this);
@@ -122,11 +109,12 @@
         isFinal: node.isFinal,
         isStatic: node.isStatic,
         typeId: _typeId(node.type),
-        localId: _memberJsNames[node],
+        localId: _memberJsNames[node]!,
         scopeId: _scopes.last.id,
         location: SourceLocation(
-            scriptId: _scriptId(node.location.file),
-            tokenPos: node.fileOffset));
+            scriptId: _scriptId(node.location!.file),
+            tokenPos: node.fileOffset,
+            endTokenPos: node.fileEndOffset));
     node.visitChildren(this);
     _scopes.last.variableIds.add(fieldSymbol.id);
     _moduleSymbols.variables.add(fieldSymbol);
@@ -135,18 +123,18 @@
   @override
   void visitLibrary(Library node) {
     var librarySymbol = LibrarySymbol(
-        name: node.name,
-        uri: node.importUri.toString(),
-        dependencies: [
-          for (var dep in node.dependencies)
-            LibrarySymbolDependency(
-                isImport: dep.isImport,
-                isDeferred: dep.isDeferred,
-                // TODO(nshahan) Need to handle prefixes.
-                targetId: dep.targetLibrary.importUri.toString())
-        ],
-        variableIds: <String>[],
-        scopeIds: <String>[]);
+      name: node.name,
+      uri: node.importUri.toString(),
+      dependencies: [
+        for (var dep in node.dependencies)
+          LibrarySymbolDependency(
+              isImport: dep.isImport,
+              isDeferred: dep.isDeferred,
+              // TODO(nshahan) Need to handle prefixes.
+              targetId: dep.targetLibrary.importUri.toString())
+      ],
+      scriptIds: [],
+    );
 
     // TODO(nshahan) Save some space by using integers as local ids?
     var scripts = [
@@ -161,7 +149,7 @@
             libraryId: librarySymbol.id),
     ];
 
-    librarySymbol.scriptIds = [for (var script in scripts) script.id];
+    librarySymbol.scriptIds.addAll(scripts.map((s) => s.id));
     _moduleSymbols.scripts.addAll(scripts);
 
     _scopes.add(librarySymbol);
@@ -195,16 +183,16 @@
   VariableSymbol _createVariableSymbol(
           VariableDeclaration node, VariableSymbolKind kind) =>
       VariableSymbol(
-          name: node.name,
+          name: node.name!,
           kind: kind,
           isConst: node.isConst,
           isFinal: node.isFinal,
           // Static fields are visited in `visitField()`.
           isStatic: false,
           typeId: _typeId(node.type),
-          localId: _variableJsNames[node],
+          localId: _variableJsNames[node]!,
           scopeId: _scopes.last.id,
           location: SourceLocation(
-              scriptId: _scriptId(node.location.file),
+              scriptId: _scriptId(node.location!.file),
               tokenPos: node.fileOffset));
 }
diff --git a/pkg/dev_compiler/lib/src/kernel/native_types.dart b/pkg/dev_compiler/lib/src/kernel/native_types.dart
index ef37392..665f722 100644
--- a/pkg/dev_compiler/lib/src/kernel/native_types.dart
+++ b/pkg/dev_compiler/lib/src/kernel/native_types.dart
@@ -2,11 +2,11 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// @dart = 2.9
-
 import 'dart:collection';
+
 import 'package:kernel/core_types.dart';
 import 'package:kernel/kernel.dart';
+
 import 'constants.dart';
 import 'kernel_helpers.dart';
 import 'target.dart' show allowedNativeTest;
@@ -154,11 +154,11 @@
     return const [];
   }
 
-  /// If this [annotation] is `@Native` or `@JsPeerInterface`, returns the "name"
-  /// field (which is also the constructor parameter).
-  String _getNativeAnnotationName(Expression annotation) {
+  /// If this [annotation] is `@Native` or `@JsPeerInterface`, returns the
+  /// "name" field (which is also the constructor parameter).
+  String? _getNativeAnnotationName(Expression annotation) {
     if (!_isNativeAnnotation(annotation)) return null;
-    return constants.getFieldValueFromAnnotation(annotation, 'name') as String;
+    return constants.getFieldValueFromAnnotation(annotation, 'name') as String?;
   }
 }
 
diff --git a/pkg/dev_compiler/lib/src/kernel/target.dart b/pkg/dev_compiler/lib/src/kernel/target.dart
index 7985eb6..bb79eb8 100644
--- a/pkg/dev_compiler/lib/src/kernel/target.dart
+++ b/pkg/dev_compiler/lib/src/kernel/target.dart
@@ -8,6 +8,7 @@
     show Message, LocatedMessage;
 import 'package:_js_interop_checks/js_interop_checks.dart';
 import 'package:_js_interop_checks/src/transformations/js_util_optimizer.dart';
+import 'package:_js_interop_checks/src/transformations/static_interop_class_eraser.dart';
 import 'package:kernel/class_hierarchy.dart';
 import 'package:kernel/core_types.dart';
 import 'package:kernel/kernel.dart';
@@ -188,6 +189,7 @@
       ChangedStructureNotifier? changedStructureNotifier}) {
     _nativeClasses ??= JsInteropChecks.getNativeClasses(component);
     var jsUtilOptimizer = JsUtilOptimizer(coreTypes, hierarchy);
+    var staticInteropClassEraser = StaticInteropClassEraser(coreTypes);
     for (var library in libraries) {
       _CovarianceTransformer(library).transform();
       JsInteropChecks(
@@ -196,6 +198,7 @@
               _nativeClasses!)
           .visitLibrary(library);
       jsUtilOptimizer.visitLibrary(library);
+      staticInteropClassEraser.visitLibrary(library);
     }
   }
 
diff --git a/pkg/dev_compiler/pubspec.yaml b/pkg/dev_compiler/pubspec.yaml
index f8e49e9..0d15516 100644
--- a/pkg/dev_compiler/pubspec.yaml
+++ b/pkg/dev_compiler/pubspec.yaml
@@ -3,7 +3,7 @@
 publish_to: none
 
 environment:
-  sdk: '>=2.12.0 <3.0.0'
+  sdk: '>=2.15.0 <3.0.0'
 
 dependencies:
   _fe_analyzer_shared: any
diff --git a/pkg/dev_compiler/test/module_symbols/class_symbols_test.dart b/pkg/dev_compiler/test/module_symbols/class_symbols_test.dart
index e1af8a8..6ebcbba 100644
--- a/pkg/dev_compiler/test/module_symbols/class_symbols_test.dart
+++ b/pkg/dev_compiler/test/module_symbols/class_symbols_test.dart
@@ -71,12 +71,10 @@
             expect(classSymbol.location.scriptId, endsWith('/foo.dart'));
           });
           test('has start token', () async {
-            expect(classSymbol.location.tokenPos,
-                22 + options.dartLangComment.length);
+            expect(classSymbol.location.tokenPos, source.indexOf('class A'));
           });
           test('has end token', () async {
-            expect(classSymbol.location.endTokenPos,
-                31 + options.dartLangComment.length);
+            expect(classSymbol.location.endTokenPos, source.lastIndexOf('}'));
           });
         });
         test('no fields', () async {
diff --git a/pkg/dev_compiler/test/module_symbols/function_symbols_test.dart b/pkg/dev_compiler/test/module_symbols/function_symbols_test.dart
index f39f27b..9c58e06 100644
--- a/pkg/dev_compiler/test/module_symbols/function_symbols_test.dart
+++ b/pkg/dev_compiler/test/module_symbols/function_symbols_test.dart
@@ -66,11 +66,11 @@
           });
           test('has start token', () async {
             expect(functionSymbol.location.tokenPos,
-                27 + options.dartLangComment.length);
+                source.indexOf('topLevelFunction'));
           });
           test('has end token', () async {
-            expect(functionSymbol.location.endTokenPos,
-                78 + options.dartLangComment.length);
+            expect(
+                functionSymbol.location.endTokenPos, source.lastIndexOf('}'));
           });
         });
         test('id in LibrarySymbol scopes', () async {
diff --git a/pkg/dev_compiler/test/module_symbols/module_symbols_json_test.dart b/pkg/dev_compiler/test/module_symbols/module_symbols_json_test.dart
index 586f202..ad23ffd 100644
--- a/pkg/dev_compiler/test/module_symbols/module_symbols_json_test.dart
+++ b/pkg/dev_compiler/test/module_symbols/module_symbols_json_test.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// @dart = 2.9
-
 import 'package:dev_compiler/src/kernel/module_symbols.dart';
 import 'package:test/test.dart';
 
@@ -26,7 +24,12 @@
 ''';
 
 void main() {
-  var intType = ClassSymbol(name: 'int', localId: 'int', scopeId: 'dart:core');
+  var intType = ClassSymbol(
+      name: 'int',
+      localId: 'int',
+      scopeId: 'dart:core',
+      location: SourceLocation(
+          scriptId: 'sdkIdForTest', tokenPos: 42, endTokenPos: 42));
 
   var libraryId = 'lib1';
   var main = Script(
@@ -243,14 +246,16 @@
 
   test('Read supported version', () {
     var version = SemanticVersion(0, 2, 3).version;
-    var json = ModuleSymbols(version: version).toJson();
+    var json = ModuleSymbols(version: version, moduleName: 'moduleNameForTest')
+        .toJson();
 
     expect(ModuleSymbols.fromJson(json).version, equals(version));
   });
 
   test('Read unsupported version', () {
     var version = SemanticVersion(1, 2, 3).version;
-    var json = ModuleSymbols(version: version).toJson();
+    var json = ModuleSymbols(version: version, moduleName: 'moduleNameForTest')
+        .toJson();
 
     expect(() => ModuleSymbols.fromJson(json), throwsException);
   });
@@ -300,7 +305,8 @@
     .having((cls) => cls.libraryId, 'libraryId', other.libraryId)
     .having((cls) => cls.scopeIds, 'scopeIds', other.scopeIds)
     .having((cls) => cls.variableIds, 'variableIds', other.variableIds)
-    .having((cls) => cls.location, 'location', matchesLocation(other.location));
+    .having(
+        (cls) => cls.location, 'location', matchesLocation(other.location!));
 
 TypeMatcher<FunctionTypeSymbol> matchesFunctionType(FunctionTypeSymbol other) =>
     isA<FunctionTypeSymbol>()
@@ -315,8 +321,8 @@
             'optionalParameterTypeIds', other.optionalParameterTypeIds)
         .having((fun) => fun.namedParameterTypeIds, 'namedParameterTypeIds',
             other.namedParameterTypeIds)
-        .having(
-            (fun) => fun.location, 'location', matchesLocation(other.location));
+        .having((fun) => fun.location, 'location',
+            matchesLocation(other.location!));
 
 TypeMatcher<FunctionSymbol> matchesFunction(FunctionSymbol other) =>
     isA<FunctionSymbol>()
@@ -329,8 +335,8 @@
         .having((fun) => fun.typeId, 'typeId', other.typeId)
         .having((fun) => fun.scopeIds, 'scopeIds', other.scopeIds)
         .having((fun) => fun.variableIds, 'variableIds', other.variableIds)
-        .having(
-            (fun) => fun.location, 'location', matchesLocation(other.location));
+        .having((fun) => fun.location, 'location',
+            matchesLocation(other.location!));
 
 TypeMatcher<ScopeSymbol> matchesScope(ScopeSymbol other) => isA<ScopeSymbol>()
     .having((scope) => scope.localId, 'localId', other.localId)
@@ -338,8 +344,8 @@
     .having((scope) => scope.id, 'id', other.id)
     .having((scope) => scope.scopeIds, 'scopeIds', other.scopeIds)
     .having((scope) => scope.variableIds, 'variableIds', other.variableIds)
-    .having(
-        (scope) => scope.location, 'location', matchesLocation(other.location));
+    .having((scope) => scope.location, 'location',
+        matchesLocation(other.location!));
 
 TypeMatcher<VariableSymbol> matchesVariable(VariableSymbol other) =>
     isA<VariableSymbol>()
@@ -351,7 +357,7 @@
         .having((variable) => variable.isStatic, 'isStatic', other.isStatic)
         .having((variable) => variable.isFinal, 'isFinal', other.isFinal)
         .having((variable) => variable.location, 'location',
-            matchesLocation(other.location));
+            matchesLocation(other.location!));
 
 TypeMatcher<Script> matchesScript(Script other) => isA<Script>()
     .having((script) => script.uri, 'uri', other.uri)
diff --git a/pkg/dev_compiler/test/module_symbols/variable_symbols_test.dart b/pkg/dev_compiler/test/module_symbols/variable_symbols_test.dart
index 64b3e57..b6421d1 100644
--- a/pkg/dev_compiler/test/module_symbols/variable_symbols_test.dart
+++ b/pkg/dev_compiler/test/module_symbols/variable_symbols_test.dart
@@ -62,10 +62,13 @@
           test('has scriptId', () async {
             expect(variableSymbol.location.scriptId, endsWith('/foo.dart'));
           });
-          test('only start token', () async {
+          test('start token position', () async {
             expect(variableSymbol.location.tokenPos,
-                47 + options.dartLangComment.length);
-            expect(variableSymbol.location.endTokenPos, null);
+                source.indexOf('globalVariable'));
+          });
+          test('end token position', () async {
+            expect(
+                variableSymbol.location.endTokenPos, source.lastIndexOf(';'));
           });
         });
       });
diff --git a/pkg/front_end/lib/src/api_prototype/experimental_flags_generated.dart b/pkg/front_end/lib/src/api_prototype/experimental_flags_generated.dart
index 50570c9..4dd9122 100644
--- a/pkg/front_end/lib/src/api_prototype/experimental_flags_generated.dart
+++ b/pkg/front_end/lib/src/api_prototype/experimental_flags_generated.dart
@@ -19,6 +19,7 @@
   extensionMethods,
   extensionTypes,
   genericMetadata,
+  macros,
   namedArgumentsAnywhere,
   nonNullable,
   nonfunctionTypeAliases,
@@ -41,6 +42,7 @@
 const Version enableExtensionMethodsVersion = const Version(2, 6);
 const Version enableExtensionTypesVersion = const Version(2, 16);
 const Version enableGenericMetadataVersion = const Version(2, 14);
+const Version enableMacrosVersion = const Version(2, 16);
 const Version enableNamedArgumentsAnywhereVersion = const Version(2, 16);
 const Version enableNonNullableVersion = const Version(2, 12);
 const Version enableNonfunctionTypeAliasesVersion = const Version(2, 13);
@@ -72,6 +74,8 @@
       return ExperimentalFlag.extensionTypes;
     case "generic-metadata":
       return ExperimentalFlag.genericMetadata;
+    case "macros":
+      return ExperimentalFlag.macros;
     case "named-arguments-anywhere":
       return ExperimentalFlag.namedArgumentsAnywhere;
     case "non-nullable":
@@ -106,6 +110,7 @@
   ExperimentalFlag.extensionMethods: true,
   ExperimentalFlag.extensionTypes: false,
   ExperimentalFlag.genericMetadata: true,
+  ExperimentalFlag.macros: false,
   ExperimentalFlag.namedArgumentsAnywhere: false,
   ExperimentalFlag.nonNullable: true,
   ExperimentalFlag.nonfunctionTypeAliases: true,
@@ -128,6 +133,7 @@
   ExperimentalFlag.extensionMethods: true,
   ExperimentalFlag.extensionTypes: false,
   ExperimentalFlag.genericMetadata: true,
+  ExperimentalFlag.macros: false,
   ExperimentalFlag.namedArgumentsAnywhere: false,
   ExperimentalFlag.nonNullable: true,
   ExperimentalFlag.nonfunctionTypeAliases: true,
@@ -150,6 +156,7 @@
   ExperimentalFlag.extensionMethods: const Version(2, 6),
   ExperimentalFlag.extensionTypes: const Version(2, 16),
   ExperimentalFlag.genericMetadata: const Version(2, 14),
+  ExperimentalFlag.macros: const Version(2, 16),
   ExperimentalFlag.namedArgumentsAnywhere: const Version(2, 16),
   ExperimentalFlag.nonNullable: const Version(2, 12),
   ExperimentalFlag.nonfunctionTypeAliases: const Version(2, 13),
@@ -172,6 +179,7 @@
   ExperimentalFlag.extensionMethods: const Version(2, 6),
   ExperimentalFlag.extensionTypes: const Version(2, 16),
   ExperimentalFlag.genericMetadata: const Version(2, 14),
+  ExperimentalFlag.macros: const Version(2, 16),
   ExperimentalFlag.namedArgumentsAnywhere: const Version(2, 16),
   ExperimentalFlag.nonNullable: const Version(2, 10),
   ExperimentalFlag.nonfunctionTypeAliases: const Version(2, 13),
diff --git a/pkg/front_end/lib/src/api_unstable/vm.dart b/pkg/front_end/lib/src/api_unstable/vm.dart
index b9b4ca7..b915847 100644
--- a/pkg/front_end/lib/src/api_unstable/vm.dart
+++ b/pkg/front_end/lib/src/api_unstable/vm.dart
@@ -54,6 +54,8 @@
 export '../fasta/fasta_codes.dart'
     show
         LocatedMessage,
+        messageFfiAbiSpecificIntegerInvalid,
+        messageFfiAbiSpecificIntegerMappingInvalid,
         messageFfiExceptionalReturnNull,
         messageFfiExpectedConstant,
         messageFfiLeafCallMustNotReturnHandle,
diff --git a/pkg/front_end/lib/src/base/processed_options.dart b/pkg/front_end/lib/src/base/processed_options.dart
index b1377c6..521d5ab 100644
--- a/pkg/front_end/lib/src/base/processed_options.dart
+++ b/pkg/front_end/lib/src/base/processed_options.dart
@@ -557,6 +557,15 @@
       return _packages = await createPackagesFromFile(_raw.packagesFileUri!);
     }
 
+    if (inputs.isEmpty) {
+      return _packages = PackageConfig.empty;
+    }
+
+    // When compiling the SDK the input files are normally `dart:` URIs.
+    if (inputs.every((uri) => uri.scheme == 'dart')) {
+      return _packages = PackageConfig.empty;
+    }
+
     if (inputs.length > 1) {
       // TODO(sigmund): consider not reporting an error if we would infer
       // the same .packages file from all of the inputs.
@@ -564,15 +573,9 @@
           messageCantInferPackagesFromManyInputs, Severity.error);
       return _packages = PackageConfig.empty;
     }
-    if (inputs.isEmpty) {
-      return _packages = PackageConfig.empty;
-    }
 
     Uri input = inputs.first;
 
-    // When compiling the SDK the input files are normally `dart:` URIs.
-    if (input.scheme == 'dart') return _packages = PackageConfig.empty;
-
     if (input.scheme == 'packages') {
       report(
           messageCantInferPackagesFromPackageUri.withLocation(
@@ -581,7 +584,7 @@
       return _packages = PackageConfig.empty;
     }
 
-    return _packages = await _findPackages(inputs.first);
+    return _packages = await _findPackages(input);
   }
 
   Future<Uint8List?> _readFile(Uri uri, bool reportError) async {
diff --git a/pkg/front_end/lib/src/fasta/builder/builder.dart b/pkg/front_end/lib/src/fasta/builder/builder.dart
index f933d9f..7b208f1 100644
--- a/pkg/front_end/lib/src/fasta/builder/builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/builder.dart
@@ -200,10 +200,6 @@
   /// Returns the number of patches that was finished.
   int finishPatch();
 
-  /// Resolve constructors (lookup names in scope) recorded in this builder and
-  /// return the number of constructors resolved.
-  int resolveConstructors(covariant Builder? parent);
-
   /// Return `true` if this builder is a duplicate of another with the same
   /// name. This is `false` for the builder first declared amongst duplicates.
   bool get isDuplicate;
@@ -305,8 +301,5 @@
   }
 
   @override
-  int resolveConstructors(covariant Builder parent) => 0;
-
-  @override
   bool get isDuplicate => next != null;
 }
diff --git a/pkg/front_end/lib/src/fasta/builder/class_builder.dart b/pkg/front_end/lib/src/fasta/builder/class_builder.dart
index c8ffab5..eb36433 100644
--- a/pkg/front_end/lib/src/fasta/builder/class_builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/class_builder.dart
@@ -23,7 +23,8 @@
         TypeParameter,
         getAsTypeArguments;
 
-import 'package:kernel/class_hierarchy.dart' show ClassHierarchy;
+import 'package:kernel/class_hierarchy.dart'
+    show ClassHierarchy, ClassHierarchyMembers;
 
 import 'package:kernel/core_types.dart' show CoreTypes;
 
@@ -36,8 +37,6 @@
 
 import 'package:kernel/src/legacy_erasure.dart';
 
-import 'package:kernel/src/types.dart' show Types;
-
 import '../dill/dill_member_builder.dart';
 
 import '../fasta_codes.dart';
@@ -112,6 +111,8 @@
 
   bool get isAbstract;
 
+  bool get isMacro;
+
   bool get declaresConstConstructor;
 
   bool get isMixin;
@@ -178,7 +179,10 @@
 
   void checkSupertypes(CoreTypes coreTypes);
 
-  void handleSeenCovariant(Types types, Member interfaceMember, bool isSetter,
+  void handleSeenCovariant(
+      ClassHierarchyMembers memberHierarchy,
+      Member interfaceMember,
+      bool isSetter,
       callback(Member interfaceMember, bool isSetter));
 
   bool hasUserDefinedNoSuchMethod(
@@ -767,12 +771,15 @@
   }
 
   @override
-  void handleSeenCovariant(Types types, Member interfaceMember, bool isSetter,
+  void handleSeenCovariant(
+      ClassHierarchyMembers memberHierarchy,
+      Member interfaceMember,
+      bool isSetter,
       callback(Member interfaceMember, bool isSetter)) {
     // When a parameter is covariant we have to check that we also
     // override the same member in all parents.
     for (Supertype supertype in interfaceMember.enclosingClass!.supers) {
-      Member? member = types.hierarchy.getInterfaceMember(
+      Member? member = memberHierarchy.getInterfaceMember(
           supertype.classNode, interfaceMember.name,
           setter: isSetter);
       if (member != null) {
diff --git a/pkg/front_end/lib/src/fasta/builder/constructor_builder.dart b/pkg/front_end/lib/src/fasta/builder/constructor_builder.dart
index 1031699..f53cbfa 100644
--- a/pkg/front_end/lib/src/fasta/builder/constructor_builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/constructor_builder.dart
@@ -14,10 +14,10 @@
 import '../dill/dill_member_builder.dart';
 
 import '../kernel/body_builder.dart' show BodyBuilder;
-import '../kernel/class_hierarchy_builder.dart' show ClassMember;
 import '../kernel/constructor_tearoff_lowering.dart';
 import '../kernel/expression_generator_helper.dart'
     show ExpressionGeneratorHelper;
+import '../kernel/hierarchy/class_member.dart' show ClassMember;
 import '../kernel/utils.dart'
     show isRedirectingGenerativeConstructorImplementation;
 import '../kernel/kernel_helper.dart' show SynthesizedFunctionNode;
diff --git a/pkg/front_end/lib/src/fasta/builder/factory_builder.dart b/pkg/front_end/lib/src/fasta/builder/factory_builder.dart
index 5db68f5..86c7b96 100644
--- a/pkg/front_end/lib/src/fasta/builder/factory_builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/factory_builder.dart
@@ -8,9 +8,9 @@
 
 import '../dill/dill_member_builder.dart';
 
-import '../kernel/class_hierarchy_builder.dart';
 import '../kernel/constructor_tearoff_lowering.dart';
 import '../kernel/forest.dart';
+import '../kernel/hierarchy/class_member.dart';
 import '../kernel/internal_ast.dart';
 import '../kernel/kernel_helper.dart';
 import '../kernel/redirecting_factory_body.dart'
diff --git a/pkg/front_end/lib/src/fasta/builder/field_builder.dart b/pkg/front_end/lib/src/fasta/builder/field_builder.dart
index 229ddf9..8acdc68 100644
--- a/pkg/front_end/lib/src/fasta/builder/field_builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/field_builder.dart
@@ -16,7 +16,8 @@
 import '../fasta_codes.dart' show messageInternalProblemAlreadyInitialized;
 
 import '../kernel/body_builder.dart' show BodyBuilder;
-import '../kernel/class_hierarchy_builder.dart';
+import '../kernel/hierarchy/class_member.dart';
+import '../kernel/hierarchy/members_builder.dart';
 import '../kernel/implicit_field_type.dart';
 import '../kernel/kernel_helper.dart';
 import '../kernel/late_lowering.dart' as late_lowering;
@@ -311,10 +312,10 @@
     _overrideDependencies!.addAll(overriddenMembers);
   }
 
-  void _ensureType(ClassHierarchyBuilder hierarchy) {
+  void _ensureType(ClassMembersBuilder membersBuilder) {
     if (_typeEnsured) return;
     if (_overrideDependencies != null) {
-      hierarchy.inferFieldType(this, _overrideDependencies!);
+      membersBuilder.inferFieldType(this, _overrideDependencies!);
       _overrideDependencies = null;
     } else {
       inferType();
@@ -765,8 +766,8 @@
       : assert(forSetter != null);
 
   @override
-  void inferType(ClassHierarchyBuilder hierarchy) {
-    memberBuilder._ensureType(hierarchy);
+  void inferType(ClassMembersBuilder membersBuilder) {
+    memberBuilder._ensureType(membersBuilder);
   }
 
   @override
@@ -775,15 +776,16 @@
   }
 
   @override
-  Member getMember(ClassHierarchyBuilder hierarchy) {
-    memberBuilder._ensureType(hierarchy);
+  Member getMember(ClassMembersBuilder membersBuilder) {
+    memberBuilder._ensureType(membersBuilder);
     return memberBuilder.field;
   }
 
   @override
-  Covariance getCovariance(ClassHierarchyBuilder hierarchy) {
+  Covariance getCovariance(ClassMembersBuilder membersBuilder) {
     return _covariance ??= forSetter
-        ? new Covariance.fromMember(getMember(hierarchy), forSetter: forSetter)
+        ? new Covariance.fromMember(getMember(membersBuilder),
+            forSetter: forSetter)
         : const Covariance.empty();
   }
 
@@ -1433,20 +1435,20 @@
       : assert(isInternalImplementation != null);
 
   @override
-  Member getMember(ClassHierarchyBuilder hierarchy) {
-    fieldBuilder._ensureType(hierarchy);
+  Member getMember(ClassMembersBuilder membersBuilder) {
+    fieldBuilder._ensureType(membersBuilder);
     return _member;
   }
 
   @override
-  Covariance getCovariance(ClassHierarchyBuilder hierarchy) {
-    return _covariance ??=
-        new Covariance.fromMember(getMember(hierarchy), forSetter: forSetter);
+  Covariance getCovariance(ClassMembersBuilder membersBuilder) {
+    return _covariance ??= new Covariance.fromMember(getMember(membersBuilder),
+        forSetter: forSetter);
   }
 
   @override
-  void inferType(ClassHierarchyBuilder hierarchy) {
-    fieldBuilder._ensureType(hierarchy);
+  void inferType(ClassMembersBuilder membersBuilder) {
+    fieldBuilder._ensureType(membersBuilder);
   }
 
   @override
diff --git a/pkg/front_end/lib/src/fasta/builder/formal_parameter_builder.dart b/pkg/front_end/lib/src/fasta/builder/formal_parameter_builder.dart
index 3e47192..5c954d0 100644
--- a/pkg/front_end/lib/src/fasta/builder/formal_parameter_builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/formal_parameter_builder.dart
@@ -117,13 +117,19 @@
 
   bool get isInitializingFormal => (modifiers & initializingFormalMask) != 0;
 
+  bool get isSuperInitializingFormal =>
+      (modifiers & superInitializingFormalMask) != 0;
+
   bool get isCovariantByDeclaration => (modifiers & covariantMask) != 0;
 
   // An initializing formal parameter might be final without its
   // VariableDeclaration being final. See
   // [ProcedureBuilder.computeFormalParameterInitializerScope]..
   @override
-  bool get isAssignable => variable!.isAssignable && !isInitializingFormal;
+  bool get isAssignable =>
+      variable!.isAssignable &&
+      !isInitializingFormal &&
+      !isSuperInitializingFormal;
 
   @override
   String get fullNameForErrors => name;
@@ -171,19 +177,33 @@
   FormalParameterBuilder forFormalParameterInitializerScope() {
     // ignore: unnecessary_null_comparison
     assert(variable != null);
-    return !isInitializingFormal
-        ? this
-        : (new FormalParameterBuilder(
-            metadata,
-            modifiers | finalMask | initializingFormalMask,
-            type,
-            name,
-            null,
-            charOffset,
-            fileUri: fileUri,
-            isExtensionThis: isExtensionThis)
-          ..parent = parent
-          ..variable = variable);
+    if (isInitializingFormal) {
+      return new FormalParameterBuilder(
+          metadata,
+          modifiers | finalMask | initializingFormalMask,
+          type,
+          name,
+          null,
+          charOffset,
+          fileUri: fileUri,
+          isExtensionThis: isExtensionThis)
+        ..parent = parent
+        ..variable = variable;
+    } else if (isSuperInitializingFormal) {
+      return new FormalParameterBuilder(
+          metadata,
+          modifiers | finalMask | superInitializingFormalMask,
+          type,
+          name,
+          null,
+          charOffset,
+          fileUri: fileUri,
+          isExtensionThis: isExtensionThis)
+        ..parent = parent
+        ..variable = variable;
+    } else {
+      return this;
+    }
   }
 
   void finalizeInitializingFormal(ClassBuilder classBuilder) {
@@ -200,18 +220,22 @@
   void buildOutlineExpressions(SourceLibraryBuilder library,
       List<DelayedActionPerformer> delayedActionPerformers) {
     if (initializerToken != null) {
-      // For modular compilation we need to include initializers for optional
-      // and named parameters of const constructors into the outline - to enable
-      // constant evaluation. Similarly we need to include initializers for
-      // optional and named parameters of instance methods because these might
-      // be needed to generated noSuchMethod forwarders.
-      bool isConstConstructorParameter = false;
+      // For modular compilation we need to include default values for optional
+      // and named parameters in several cases:
+      // * for const constructors to enable constant evaluation,
+      // * for instance methods because these might be needed to generated
+      //   noSuchMethod forwarders, and
+      // * for generative constructors to support forwarding constructors
+      //   in mixin applications.
+      bool needsDefaultValues = false;
       if (parent is ConstructorBuilder) {
-        isConstConstructorParameter = parent!.isConst;
+        needsDefaultValues = true;
       } else if (parent is SourceFactoryBuilder) {
-        isConstConstructorParameter = parent!.isFactory && parent!.isConst;
+        needsDefaultValues = parent!.isFactory && parent!.isConst;
+      } else {
+        needsDefaultValues = parent!.isClassInstanceMember;
       }
-      if (isConstConstructorParameter || parent!.isClassInstanceMember) {
+      if (needsDefaultValues) {
         final ClassBuilder classBuilder = parent!.parent as ClassBuilder;
         Scope scope = classBuilder.scope;
         BodyBuilder bodyBuilder = library.loader
diff --git a/pkg/front_end/lib/src/fasta/builder/function_builder.dart b/pkg/front_end/lib/src/fasta/builder/function_builder.dart
index 0ad02c9..9bd4714 100644
--- a/pkg/front_end/lib/src/fasta/builder/function_builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/function_builder.dart
@@ -219,7 +219,8 @@
     if (formals == null) return parent;
     Map<String, Builder> local = <String, Builder>{};
     for (FormalParameterBuilder formal in formals!) {
-      if (!isConstructor || !formal.isInitializingFormal) {
+      if (!isConstructor ||
+          !formal.isInitializingFormal && !formal.isSuperInitializingFormal) {
         local[formal.name] = formal;
       }
     }
diff --git a/pkg/front_end/lib/src/fasta/builder/library_builder.dart b/pkg/front_end/lib/src/fasta/builder/library_builder.dart
index 1672a7d..f2c63b8 100644
--- a/pkg/front_end/lib/src/fasta/builder/library_builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/library_builder.dart
@@ -29,7 +29,6 @@
 
 import 'builder.dart';
 import 'class_builder.dart';
-import 'field_builder.dart';
 import 'member_builder.dart';
 import 'modifier_builder.dart';
 import 'name_iterator.dart';
@@ -101,14 +100,6 @@
       String name, Builder declaration, Builder other, int charOffset,
       {bool isExport: false, bool isImport: false});
 
-  int finishDeferredLoadTearoffs();
-
-  int finishForwarders();
-
-  int finishNativeMethods();
-
-  int finishPatchMethods();
-
   /// Looks up [constructorName] in the class named [className].
   ///
   /// The class is looked up in this library's export scope unless
@@ -124,21 +115,6 @@
   MemberBuilder getConstructor(String className,
       {String constructorName, bool bypassLibraryPrivacy: false});
 
-  int finishTypeVariables(ClassBuilder object, TypeBuilder dynamicType);
-
-  /// Computes variances of type parameters on typedefs.
-  ///
-  /// The variance property of type parameters on typedefs is computed from the
-  /// use of the parameters in the right-hand side of the typedef definition.
-  int computeVariances() => 0;
-
-  /// This method instantiates type parameters to their bounds in some cases
-  /// where they were omitted by the programmer and not provided by the type
-  /// inference.  The method returns the number of distinct type variables
-  /// that were instantiated in this library.
-  int computeDefaultTypes(TypeBuilder dynamicType, TypeBuilder nullType,
-      TypeBuilder bottomType, ClassBuilder objectClass);
-
   void becomeCoreLibrary();
 
   void addSyntheticDeclarationOfDynamic();
@@ -160,10 +136,6 @@
 
   void recordAccess(int charOffset, int length, Uri fileUri);
 
-  void buildOutlineExpressions();
-
-  List<FieldBuilder>? takeImplicitlyTypedFields();
-
   bool get isNonNullableByDefault;
 
   Nullability get nullable;
@@ -286,18 +258,6 @@
   }
 
   @override
-  int finishDeferredLoadTearoffs() => 0;
-
-  @override
-  int finishForwarders() => 0;
-
-  @override
-  int finishNativeMethods() => 0;
-
-  @override
-  int finishPatchMethods() => 0;
-
-  @override
   MemberBuilder getConstructor(String className,
       {String? constructorName, bool bypassLibraryPrivacy: false}) {
     constructorName ??= "";
@@ -340,18 +300,6 @@
   }
 
   @override
-  int finishTypeVariables(ClassBuilder object, TypeBuilder dynamicType) => 0;
-
-  @override
-  int computeVariances() => 0;
-
-  @override
-  int computeDefaultTypes(TypeBuilder dynamicType, TypeBuilder nullType,
-      TypeBuilder bottomType, ClassBuilder objectClass) {
-    return 0;
-  }
-
-  @override
   void becomeCoreLibrary() {
     if (scope.lookupLocalMember("dynamic", setter: false) == null) {
       addSyntheticDeclarationOfDynamic();
@@ -392,12 +340,6 @@
   void recordAccess(int charOffset, int length, Uri fileUri) {}
 
   @override
-  void buildOutlineExpressions() {}
-
-  @override
-  List<FieldBuilder>? takeImplicitlyTypedFields() => null;
-
-  @override
   Nullability get nullable {
     return isNonNullableByDefault ? Nullability.nullable : Nullability.legacy;
   }
@@ -438,7 +380,7 @@
 
   @override
   StringBuffer printOn(StringBuffer buffer) {
-    return buffer..write(name ?? importUri);
+    return buffer..write(name ?? (isPart ? fileUri : importUri));
   }
 }
 
diff --git a/pkg/front_end/lib/src/fasta/builder/member_builder.dart b/pkg/front_end/lib/src/fasta/builder/member_builder.dart
index 9035466..5fc860b 100644
--- a/pkg/front_end/lib/src/fasta/builder/member_builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/member_builder.dart
@@ -9,7 +9,7 @@
 
 import '../../base/common.dart';
 
-import '../kernel/class_hierarchy_builder.dart';
+import '../kernel/hierarchy/class_member.dart';
 import '../kernel/kernel_helper.dart';
 import '../modifier.dart';
 import '../problems.dart' show unsupported;
diff --git a/pkg/front_end/lib/src/fasta/builder/procedure_builder.dart b/pkg/front_end/lib/src/fasta/builder/procedure_builder.dart
index a1118c6..f09dc0d 100644
--- a/pkg/front_end/lib/src/fasta/builder/procedure_builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/procedure_builder.dart
@@ -5,7 +5,8 @@
 import 'package:kernel/ast.dart';
 import 'package:kernel/type_algebra.dart';
 
-import '../kernel/class_hierarchy_builder.dart';
+import '../kernel/hierarchy/class_member.dart';
+import '../kernel/hierarchy/members_builder.dart';
 import '../kernel/member_covariance.dart';
 
 import '../source/name_scheme.dart';
@@ -197,15 +198,15 @@
     _overrideDependencies!.addAll(overriddenMembers);
   }
 
-  void _ensureTypes(ClassHierarchyBuilder hierarchy) {
+  void _ensureTypes(ClassMembersBuilder membersBuilder) {
     if (_typeEnsured) return;
     if (_overrideDependencies != null) {
       if (isGetter) {
-        hierarchy.inferGetterType(this, _overrideDependencies!);
+        membersBuilder.inferGetterType(this, _overrideDependencies!);
       } else if (isSetter) {
-        hierarchy.inferSetterType(this, _overrideDependencies!);
+        membersBuilder.inferSetterType(this, _overrideDependencies!);
       } else {
-        hierarchy.inferMethodType(this, _overrideDependencies!);
+        membersBuilder.inferMethodType(this, _overrideDependencies!);
       }
       _overrideDependencies = null;
     }
@@ -223,6 +224,7 @@
         return procedure;
       case ProcedureKind.Operator:
       case ProcedureKind.Setter:
+        return null;
     }
   }
 
@@ -527,8 +529,8 @@
   bool get isSourceDeclaration => true;
 
   @override
-  void inferType(ClassHierarchyBuilder hierarchy) {
-    memberBuilder._ensureTypes(hierarchy);
+  void inferType(ClassMembersBuilder membersBuilder) {
+    memberBuilder._ensureTypes(membersBuilder);
   }
 
   @override
@@ -537,15 +539,15 @@
   }
 
   @override
-  Member getMember(ClassHierarchyBuilder hierarchy) {
-    memberBuilder._ensureTypes(hierarchy);
+  Member getMember(ClassMembersBuilder membersBuilder) {
+    memberBuilder._ensureTypes(membersBuilder);
     return memberBuilder.member;
   }
 
   @override
-  Covariance getCovariance(ClassHierarchyBuilder hierarchy) {
-    return _covariance ??=
-        new Covariance.fromMember(getMember(hierarchy), forSetter: forSetter);
+  Covariance getCovariance(ClassMembersBuilder membersBuilder) {
+    return _covariance ??= new Covariance.fromMember(getMember(membersBuilder),
+        forSetter: forSetter);
   }
 
   @override
diff --git a/pkg/front_end/lib/src/fasta/dill/dill_class_builder.dart b/pkg/front_end/lib/src/fasta/dill/dill_class_builder.dart
index 0a5f4e1..9ccfd18 100644
--- a/pkg/front_end/lib/src/fasta/dill/dill_class_builder.dart
+++ b/pkg/front_end/lib/src/fasta/dill/dill_class_builder.dart
@@ -50,6 +50,9 @@
   DillLibraryBuilder get library => super.library as DillLibraryBuilder;
 
   @override
+  bool get isMacro => cls.isMacro;
+
+  @override
   List<TypeVariableBuilder>? get typeVariables {
     List<TypeVariableBuilder>? typeVariables = super.typeVariables;
     if (typeVariables == null && cls.typeParameters.isNotEmpty) {
diff --git a/pkg/front_end/lib/src/fasta/dill/dill_member_builder.dart b/pkg/front_end/lib/src/fasta/dill/dill_member_builder.dart
index 4917953..d800f03 100644
--- a/pkg/front_end/lib/src/fasta/dill/dill_member_builder.dart
+++ b/pkg/front_end/lib/src/fasta/dill/dill_member_builder.dart
@@ -11,8 +11,8 @@
 import '../builder/member_builder.dart';
 import '../builder/library_builder.dart';
 
-import '../kernel/class_hierarchy_builder.dart'
-    show ClassHierarchyBuilder, ClassMember;
+import '../kernel/hierarchy/class_member.dart' show ClassMember;
+import '../kernel/hierarchy/members_builder.dart' show ClassMembersBuilder;
 import '../kernel/member_covariance.dart';
 import '../kernel/utils.dart'
     show isRedirectingGenerativeConstructorImplementation;
@@ -282,16 +282,16 @@
   }
 
   @override
-  Member getMember(ClassHierarchyBuilder hierarchy) => memberBuilder.member;
+  Member getMember(ClassMembersBuilder membersBuilder) => memberBuilder.member;
 
   @override
-  Covariance getCovariance(ClassHierarchyBuilder hierarchy) {
+  Covariance getCovariance(ClassMembersBuilder membersBuilder) {
     return _covariance ??=
         new Covariance.fromMember(memberBuilder.member, forSetter: forSetter);
   }
 
   @override
-  void inferType(ClassHierarchyBuilder hierarchy) {
+  void inferType(ClassMembersBuilder hierarchy) {
     // Do nothing; this is only for source members.
   }
 
diff --git a/pkg/front_end/lib/src/fasta/incremental_compiler.dart b/pkg/front_end/lib/src/fasta/incremental_compiler.dart
index 03b4da8..31d90c59 100644
--- a/pkg/front_end/lib/src/fasta/incremental_compiler.dart
+++ b/pkg/front_end/lib/src/fasta/incremental_compiler.dart
@@ -122,7 +122,7 @@
 
 import 'hybrid_file_system.dart' show HybridFileSystem;
 
-import 'kernel/class_hierarchy_builder.dart' show ClassHierarchyBuilder;
+import 'kernel/hierarchy/hierarchy_builder.dart' show ClassHierarchyBuilder;
 
 import 'kernel/internal_ast.dart' show VariableDeclarationImpl;
 
@@ -465,24 +465,17 @@
     Set<Library> newDillLibraryBuilders = new Set<Library>();
     _userBuilders ??= <Uri, LibraryBuilder>{};
     Map<LibraryBuilder, List<LibraryBuilder>>? convertedLibraries;
-    for (LibraryBuilder builder
-        in nextGoodKernelTarget.loader.libraryBuilders) {
-      if (builder is SourceLibraryBuilder) {
-        DillLibraryBuilder dillBuilder =
-            _dillLoadedData!.loader.appendLibrary(builder.library);
-        nextGoodKernelTarget.loader.registerLibraryBuilder(
-            // TODO(johnniwinther): Why do we need to create
-            //  [DillLibraryBuilder]s for the patch library file uris?
-            dillBuilder,
-            builder.isPatch ? builder.fileUri : null);
-        _userBuilders![builder.importUri] = dillBuilder;
-        newDillLibraryBuilders.add(builder.library);
-        changed = true;
-        if (experimentalInvalidation != null) {
-          convertedLibraries ??=
-              new Map<LibraryBuilder, List<LibraryBuilder>>();
-          convertedLibraries[builder] = [dillBuilder];
-        }
+    for (SourceLibraryBuilder builder
+        in nextGoodKernelTarget.loader.sourceLibraryBuilders) {
+      DillLibraryBuilder dillBuilder =
+          _dillLoadedData!.loader.appendLibrary(builder.library);
+      nextGoodKernelTarget.loader.registerLibraryBuilder(dillBuilder);
+      _userBuilders![builder.importUri] = dillBuilder;
+      newDillLibraryBuilders.add(builder.library);
+      changed = true;
+      if (experimentalInvalidation != null) {
+        convertedLibraries ??= new Map<LibraryBuilder, List<LibraryBuilder>>();
+        convertedLibraries[builder] = [dillBuilder];
       }
     }
     if (changed) {
@@ -527,7 +520,7 @@
       }
     }
     nextGoodKernelTarget.loader.buildersCreatedWithReferences.clear();
-    nextGoodKernelTarget.loader.builderHierarchy.clear();
+    nextGoodKernelTarget.loader.hierarchyBuilder.clear();
     nextGoodKernelTarget.loader.referenceFromIndex = null;
     convertedLibraries = null;
     experimentalInvalidation = null;
@@ -537,6 +530,8 @@
 
   bool _checkEquivalentScopes(
       SourceLoader sourceLoader, DillLoader dillLoader) {
+    // TODO(johnniwinther): Use [SourceLoader.sourceLibraryBuilders] here.
+    // Currently this causes a failure in incremental_dartino_suite.dart.
     for (LibraryBuilder sourceLibraryBuilder in sourceLoader.libraryBuilders) {
       if (sourceLibraryBuilder is SourceLibraryBuilder) {
         Uri uri = sourceLibraryBuilder.importUri;
@@ -703,7 +698,7 @@
     }
 
     updateNeededDillLibrariesWithHierarchy(
-        neededDillLibraries, hierarchy, target.loader.builderHierarchy);
+        neededDillLibraries, hierarchy, target.loader.hierarchyBuilder);
 
     return neededDillLibraries;
   }
@@ -759,9 +754,8 @@
         new Map<LibraryBuilder, List<LibraryBuilder>>.identity();
     if (experimentalInvalidation != null) {
       for (LibraryBuilder library in experimentalInvalidation.rebuildBodies) {
-        LibraryBuilder newBuilder = currentKernelTarget.loader.read(
-            library.importUri, -1,
-            accessorUri: currentKernelTarget.loader.firstUri,
+        LibraryBuilder newBuilder = currentKernelTarget.loader.readAsEntryPoint(
+            library.importUri,
             fileUri: library.fileUri,
             referencesFrom: library.library);
         List<LibraryBuilder> builders = [newBuilder];
@@ -1666,9 +1660,8 @@
     assert(_dillLoadedData != null && lastGoodKernelTarget != null);
 
     return await context.runInContext((_) async {
-      LibraryBuilder libraryBuilder = lastGoodKernelTarget!.loader.read(
-          libraryUri, -1,
-          accessorUri: lastGoodKernelTarget.loader.firstUri);
+      LibraryBuilder libraryBuilder =
+          lastGoodKernelTarget!.loader.readAsEntryPoint(libraryUri);
       _ticker.logMs("Loaded library $libraryUri");
 
       Class? cls;
@@ -1733,12 +1726,11 @@
       }
 
       SourceLibraryBuilder debugLibrary = new SourceLibraryBuilder(
-        libraryUri,
-        debugExprUri,
-        /*packageUri*/ null,
-        new ImplicitLanguageVersion(libraryBuilder.library.languageVersion),
-        lastGoodKernelTarget.loader,
-        null,
+        importUri: libraryUri,
+        fileUri: debugExprUri,
+        packageLanguageVersion:
+            new ImplicitLanguageVersion(libraryBuilder.library.languageVersion),
+        loader: lastGoodKernelTarget.loader,
         scope: libraryBuilder.scope.createNestedScope("expression"),
         nameOrigin: libraryBuilder,
       );
@@ -2585,9 +2577,11 @@
       for (String jsonString in problemsAsJson) {
         DiagnosticMessageFromJson message =
             new DiagnosticMessageFromJson.fromJson(jsonString);
-        assert(message.uri != null ||
-            (message.involvedFiles != null &&
-                message.involvedFiles!.isNotEmpty));
+        assert(
+            message.uri != null ||
+                (message.involvedFiles != null &&
+                    message.involvedFiles!.isNotEmpty),
+            jsonString);
         if (message.uri != null) {
           List<DiagnosticMessageFromJson> messages =
               _remainingComponentProblems[message.uri!] ??=
diff --git a/pkg/front_end/lib/src/fasta/kernel/body_builder.dart b/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
index dad946b..44ee19e 100644
--- a/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
@@ -306,8 +306,7 @@
 
   /// List of built redirecting factory invocations.  The targets of the
   /// invocations are to be resolved in a separate step.
-  final List<FactoryConstructorInvocation> redirectingFactoryInvocations =
-      <FactoryConstructorInvocation>[];
+  final List<FactoryConstructorInvocation> redirectingFactoryInvocations = [];
 
   /// List of redirecting factory invocations delayed for resolution.
   ///
@@ -315,7 +314,7 @@
   /// the inference in the declaration of the redirecting factory isn't done
   /// yet.
   final List<FactoryConstructorInvocation>
-      delayedRedirectingFactoryInvocations = <FactoryConstructorInvocation>[];
+      delayedRedirectingFactoryInvocations = [];
 
   /// List of built type aliased generative constructor invocations that
   /// require unaliasing.
@@ -326,6 +325,13 @@
   /// unaliasing.
   final List<TypeAliasedFactoryInvocation> typeAliasedFactoryInvocations = [];
 
+  /// List of type aliased factory invocations delayed for resolution.
+  ///
+  /// A resolution of a type aliased factory invocation can be delayed because
+  /// the inference in the declaration of the target isn't done yet.
+  final List<TypeAliasedFactoryInvocation>
+      delayedTypeAliasedFactoryInvocations = [];
+
   /// Variables with metadata.  Their types need to be inferred late, for
   /// example, in [finishFunction].
   List<VariableDeclaration>? variablesWithMetadata;
@@ -897,9 +903,8 @@
       [List<DelayedActionPerformer>? delayedActionPerformers]) {
     _finishVariableMetadata();
     _unaliasTypeAliasedConstructorInvocations();
-    _unaliasTypeAliasedFactoryInvocations();
-    _resolveRedirectingFactoryTargets(
-        redirectingFactoryInvocations, delayedRedirectingFactoryInvocations);
+    _unaliasTypeAliasedFactoryInvocations(typeAliasedFactoryInvocations);
+    _resolveRedirectingFactoryTargets(redirectingFactoryInvocations);
     libraryBuilder.checkUncheckedTypedefTypes(typeEnvironment);
     if (hasDelayedActions) {
       assert(
@@ -1043,6 +1048,7 @@
         buildInvalidInitializer(node as Expression, token.charOffset)
       ];
     }
+
     _initializers ??= <Initializer>[];
     _initializers!.addAll(initializers);
   }
@@ -1349,9 +1355,7 @@
   }
 
   void _resolveRedirectingFactoryTargets(
-      List<FactoryConstructorInvocation> redirectingFactoryInvocations,
-      List<FactoryConstructorInvocation>?
-          delayedRedirectingFactoryInvocations) {
+      List<FactoryConstructorInvocation> redirectingFactoryInvocations) {
     List<FactoryConstructorInvocation> invocations =
         redirectingFactoryInvocations.toList();
     redirectingFactoryInvocations.clear();
@@ -1381,7 +1385,7 @@
           invocation.fileOffset,
           invocation.isConst);
       if (replacement == null) {
-        delayedRedirectingFactoryInvocations?.add(invocation);
+        delayedRedirectingFactoryInvocations.add(invocation);
       } else {
         invocation.replaceWith(replacement);
       }
@@ -1414,9 +1418,12 @@
     typeAliasedConstructorInvocations.clear();
   }
 
-  void _unaliasTypeAliasedFactoryInvocations() {
-    for (TypeAliasedFactoryInvocation invocation
-        in typeAliasedFactoryInvocations) {
+  void _unaliasTypeAliasedFactoryInvocations(
+      List<TypeAliasedFactoryInvocation> typeAliasedFactoryInvocations) {
+    List<TypeAliasedFactoryInvocation> invocations =
+        typeAliasedFactoryInvocations.toList();
+    typeAliasedFactoryInvocations.clear();
+    for (TypeAliasedFactoryInvocation invocation in invocations) {
       bool inferred = !hasExplicitTypeArguments(invocation.arguments);
       DartType aliasedType = new TypedefType(
           invocation.typeAliasBuilder.typedef,
@@ -1436,8 +1443,16 @@
           named: invocation.arguments.named,
           hasExplicitTypeArguments:
               hasExplicitTypeArguments(invocation.arguments));
-      invocation.replaceWith(_resolveRedirectingFactoryTarget(invocation.target,
-          invocationArguments, invocation.fileOffset, invocation.isConst)!);
+      Expression? replacement = _resolveRedirectingFactoryTarget(
+          invocation.target,
+          invocationArguments,
+          invocation.fileOffset,
+          invocation.isConst);
+      if (replacement == null) {
+        delayedTypeAliasedFactoryInvocations.add(invocation);
+      } else {
+        invocation.replaceWith(replacement);
+      }
     }
     typeAliasedFactoryInvocations.clear();
   }
@@ -1451,8 +1466,7 @@
   @override
   void performDelayedActions() {
     if (delayedRedirectingFactoryInvocations.isNotEmpty) {
-      _resolveRedirectingFactoryTargets(
-          delayedRedirectingFactoryInvocations, null);
+      _resolveRedirectingFactoryTargets(delayedRedirectingFactoryInvocations);
       if (delayedRedirectingFactoryInvocations.isNotEmpty) {
         for (StaticInvocation invocation
             in delayedRedirectingFactoryInvocations) {
@@ -1464,11 +1478,26 @@
         }
       }
     }
+    if (delayedTypeAliasedFactoryInvocations.isNotEmpty) {
+      _unaliasTypeAliasedFactoryInvocations(
+          delayedTypeAliasedFactoryInvocations);
+      if (delayedTypeAliasedFactoryInvocations.isNotEmpty) {
+        for (StaticInvocation invocation
+            in delayedTypeAliasedFactoryInvocations) {
+          internalProblem(
+              fasta.templateInternalProblemUnhandled.withArguments(
+                  invocation.target.name.text, 'performDelayedActions'),
+              invocation.fileOffset,
+              uri);
+        }
+      }
+    }
   }
 
   @override
   bool get hasDelayedActions {
-    return delayedRedirectingFactoryInvocations.isNotEmpty;
+    return delayedRedirectingFactoryInvocations.isNotEmpty ||
+        delayedTypeAliasedFactoryInvocations.isNotEmpty;
   }
 
   void _finishVariableMetadata() {
@@ -1647,15 +1676,87 @@
         typeInferrer.flowAnalysis.declare(parameter.variable!, true);
       }
     }
-    if (_initializers != null) {
+
+    List<Expression>? positionalSuperParametersAsArguments;
+    List<NamedExpression>? namedSuperParametersAsArguments;
+    if (formals != null) {
+      for (FormalParameterBuilder formal in formals) {
+        if (formal.isSuperInitializingFormal) {
+          if (formal.isNamed) {
+            (namedSuperParametersAsArguments ??= <NamedExpression>[]).add(
+                new NamedExpression(
+                    formal.name,
+                    new VariableGetImpl(formal.variable!,
+                        forNullGuardedAccess: false)
+                      ..fileOffset = formal.charOffset)
+                  ..fileOffset = formal.charOffset);
+          } else {
+            (positionalSuperParametersAsArguments ??= <Expression>[]).add(
+                new VariableGetImpl(formal.variable!,
+                    forNullGuardedAccess: false)
+                  ..fileOffset = formal.charOffset);
+          }
+        }
+      }
+    }
+
+    List<Initializer>? initializers = _initializers;
+    if (initializers != null) {
+      if (libraryBuilder.enableSuperParametersInLibrary) {
+        if (initializers.isNotEmpty && initializers.last is SuperInitializer) {
+          SuperInitializer superInitializer =
+              initializers.last as SuperInitializer;
+          Arguments arguments = superInitializer.arguments;
+
+          if (positionalSuperParametersAsArguments != null) {
+            if (arguments.positional.isNotEmpty) {
+              addProblem(fasta.messagePositionalSuperParametersAndArguments,
+                  arguments.fileOffset, noLength,
+                  context: <LocatedMessage>[
+                    fasta.messageSuperInitializerParameter.withLocation(
+                        uri,
+                        (positionalSuperParametersAsArguments.first
+                                as VariableGet)
+                            .variable
+                            .fileOffset,
+                        noLength)
+                  ]);
+            } else {
+              arguments.positional.addAll(positionalSuperParametersAsArguments);
+            }
+          }
+          if (namedSuperParametersAsArguments != null) {
+            // TODO(cstefantsova): Report name conflicts.
+            arguments.named.addAll(namedSuperParametersAsArguments);
+          }
+
+          LocatedMessage? message = checkArgumentsForFunction(
+              superInitializer.target.function,
+              arguments,
+              arguments.fileOffset, <TypeParameter>[]);
+          if (message != null) {
+            initializers[initializers.length - 1] = buildInvalidInitializer(
+                buildUnresolvedError(
+                    forest.createNullLiteral(superInitializer.fileOffset),
+                    constructorNameForDiagnostics(
+                        superInitializer.target.name.text),
+                    arguments,
+                    superInitializer.fileOffset,
+                    isSuper: true,
+                    message: message,
+                    kind: UnresolvedKind.Constructor));
+          }
+        }
+      }
+
       Map<Initializer, InitializerInferenceResult> inferenceResults =
           <Initializer, InitializerInferenceResult>{};
-      for (Initializer initializer in _initializers!) {
+      for (Initializer initializer in initializers) {
         inferenceResults[initializer] =
             typeInferrer.inferInitializer(this, initializer);
       }
       if (!builder.isExternal) {
-        for (Initializer initializer in _initializers!) {
+        for (Initializer initializer in initializers) {
           builder.addInitializer(initializer, this,
               inferenceResult: inferenceResults[initializer]!);
         }
@@ -1671,7 +1772,14 @@
       /// >unless the enclosing class is class Object.
       Constructor? superTarget = lookupConstructor(emptyName, isSuper: true);
       Initializer initializer;
-      Arguments arguments = forest.createArgumentsEmpty(noLocation);
+      Arguments arguments;
+      if (libraryBuilder.enableSuperParametersInLibrary) {
+        arguments = forest.createArguments(
+            noLocation, positionalSuperParametersAsArguments ?? <Expression>[],
+            named: namedSuperParametersAsArguments);
+      } else {
+        arguments = forest.createArgumentsEmpty(noLocation);
+      }
       if (superTarget == null ||
           checkArgumentsForFunction(superTarget.function, arguments,
                   builder.charOffset, const <TypeParameter>[]) !=
diff --git a/pkg/front_end/lib/src/fasta/kernel/class_hierarchy_builder.dart b/pkg/front_end/lib/src/fasta/kernel/class_hierarchy_builder.dart
deleted file mode 100644
index 8508470..0000000
--- a/pkg/front_end/lib/src/fasta/kernel/class_hierarchy_builder.dart
+++ /dev/null
@@ -1,4416 +0,0 @@
-// Copyright (c) 2018, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-library fasta.class_hierarchy_builder;
-
-import 'package:kernel/ast.dart';
-
-import 'package:kernel/class_hierarchy.dart'
-    show ClassHierarchy, ClassHierarchyBase;
-
-import 'package:kernel/core_types.dart' show CoreTypes;
-
-import 'package:kernel/type_algebra.dart' show Substitution, uniteNullabilities;
-import 'package:kernel/type_environment.dart';
-
-import 'package:kernel/src/legacy_erasure.dart';
-import 'package:kernel/src/nnbd_top_merge.dart';
-import 'package:kernel/src/norm.dart';
-import 'package:kernel/src/standard_bounds.dart';
-import 'package:kernel/src/types.dart' show Types;
-
-import '../../base/common.dart';
-import '../../testing/id_testing_utils.dart' show typeToText;
-
-import '../builder/builder.dart';
-import '../builder/class_builder.dart';
-import '../builder/field_builder.dart';
-import '../builder/formal_parameter_builder.dart';
-import '../builder/library_builder.dart';
-import '../builder/member_builder.dart';
-import '../builder/named_type_builder.dart';
-import '../builder/procedure_builder.dart';
-import '../builder/type_alias_builder.dart';
-import '../builder/type_builder.dart';
-import '../builder/type_declaration_builder.dart';
-
-import '../loader.dart' show Loader;
-
-import '../messages.dart'
-    show
-        LocatedMessage,
-        Message,
-        messageDeclaredMemberConflictsWithInheritedMember,
-        messageDeclaredMemberConflictsWithInheritedMemberCause,
-        messageDeclaredMemberConflictsWithOverriddenMembersCause,
-        messageInheritedMembersConflict,
-        messageInheritedMembersConflictCause1,
-        messageInheritedMembersConflictCause2,
-        messageStaticAndInstanceConflict,
-        messageStaticAndInstanceConflictCause,
-        templateCantInferTypesDueToNoCombinedSignature,
-        templateCantInferReturnTypeDueToNoCombinedSignature,
-        templateCantInferTypeDueToNoCombinedSignature,
-        templateCombinedMemberSignatureFailed,
-        templateDuplicatedDeclaration,
-        templateDuplicatedDeclarationCause,
-        templateMissingImplementationCause,
-        templateMissingImplementationNotAbstract;
-
-import '../names.dart' show noSuchMethodName;
-
-import '../scope.dart' show Scope;
-
-import '../source/source_class_builder.dart';
-import '../source/source_library_builder.dart' show SourceLibraryBuilder;
-
-import '../source/source_loader.dart' show SourceLoader;
-
-import '../type_inference/standard_bounds.dart' show TypeSchemaStandardBounds;
-
-import '../type_inference/type_constraint_gatherer.dart'
-    show TypeConstraintGatherer;
-
-import '../type_inference/type_inferrer.dart' show MixinInferrer;
-
-import '../type_inference/type_schema.dart' show UnknownType;
-
-import '../type_inference/type_schema_environment.dart' show TypeConstraint;
-
-import 'combined_member_signature.dart';
-
-import 'member_covariance.dart';
-
-import 'forwarding_node.dart' show ForwardingNode;
-
-const DebugLogger? debug =
-    const bool.fromEnvironment("debug.hierarchy") ? const DebugLogger() : null;
-
-class DebugLogger {
-  const DebugLogger();
-  void log(Object message) => print(message);
-}
-
-int compareDeclarations(ClassMember a, ClassMember b) {
-  if (a == b) return 0;
-  return ClassHierarchy.compareNames(a.name, b.name);
-}
-
-int compareClassMembers(ClassMember a, ClassMember b) {
-  if (a.forSetter == b.forSetter) {
-    return compareDeclarations(a, b);
-  } else if (a.forSetter) {
-    return 1;
-  } else {
-    return -1;
-  }
-}
-
-bool isNameVisibleIn(Name name, LibraryBuilder libraryBuilder) {
-  return !name.isPrivate || name.library == libraryBuilder.library;
-}
-
-class Tuple {
-  final Name name;
-  ClassMember? _declaredMember;
-  ClassMember? _declaredSetter;
-  ClassMember? _mixedInMember;
-  ClassMember? _mixedInSetter;
-  ClassMember? _extendedMember;
-  ClassMember? _extendedSetter;
-  List<ClassMember>? _implementedMembers;
-  List<ClassMember>? _implementedSetters;
-
-  Tuple.declareMember(ClassMember declaredMember)
-      : assert(!declaredMember.forSetter),
-        this._declaredMember = declaredMember,
-        this.name = declaredMember.name;
-
-  Tuple.mixInMember(ClassMember mixedInMember)
-      : assert(!mixedInMember.forSetter),
-        this._mixedInMember = mixedInMember,
-        this.name = mixedInMember.name;
-
-  Tuple.extendMember(ClassMember extendedMember)
-      : assert(!extendedMember.forSetter),
-        this._extendedMember = extendedMember,
-        this.name = extendedMember.name;
-
-  Tuple.implementMember(ClassMember implementedMember)
-      : assert(!implementedMember.forSetter),
-        this.name = implementedMember.name,
-        _implementedMembers = <ClassMember>[implementedMember];
-
-  Tuple.declareSetter(ClassMember declaredSetter)
-      : assert(declaredSetter.forSetter),
-        this._declaredSetter = declaredSetter,
-        this.name = declaredSetter.name;
-
-  Tuple.mixInSetter(ClassMember mixedInSetter)
-      : assert(mixedInSetter.forSetter),
-        this._mixedInSetter = mixedInSetter,
-        this.name = mixedInSetter.name;
-
-  Tuple.extendSetter(ClassMember extendedSetter)
-      : assert(extendedSetter.forSetter),
-        this._extendedSetter = extendedSetter,
-        this.name = extendedSetter.name;
-
-  Tuple.implementSetter(ClassMember implementedSetter)
-      : assert(implementedSetter.forSetter),
-        this.name = implementedSetter.name,
-        _implementedSetters = <ClassMember>[implementedSetter];
-
-  ClassMember? get declaredMember => _declaredMember;
-
-  void set declaredMember(ClassMember? value) {
-    assert(!value!.forSetter);
-    assert(
-        _declaredMember == null,
-        "Declared member already set to $_declaredMember, "
-        "trying to set it to $value.");
-    _declaredMember = value;
-  }
-
-  ClassMember? get declaredSetter => _declaredSetter;
-
-  void set declaredSetter(ClassMember? value) {
-    assert(value!.forSetter);
-    assert(
-        _declaredSetter == null,
-        "Declared setter already set to $_declaredSetter, "
-        "trying to set it to $value.");
-    _declaredSetter = value;
-  }
-
-  ClassMember? get extendedMember => _extendedMember;
-
-  void set extendedMember(ClassMember? value) {
-    assert(!value!.forSetter);
-    assert(
-        _extendedMember == null,
-        "Extended member already set to $_extendedMember, "
-        "trying to set it to $value.");
-    _extendedMember = value;
-  }
-
-  ClassMember? get extendedSetter => _extendedSetter;
-
-  void set extendedSetter(ClassMember? value) {
-    assert(value!.forSetter);
-    assert(
-        _extendedSetter == null,
-        "Extended setter already set to $_extendedSetter, "
-        "trying to set it to $value.");
-    _extendedSetter = value;
-  }
-
-  ClassMember? get mixedInMember => _mixedInMember;
-
-  void set mixedInMember(ClassMember? value) {
-    assert(!value!.forSetter);
-    assert(
-        _mixedInMember == null,
-        "Mixed in member already set to $_mixedInMember, "
-        "trying to set it to $value.");
-    _mixedInMember = value;
-  }
-
-  ClassMember? get mixedInSetter => _mixedInSetter;
-
-  void set mixedInSetter(ClassMember? value) {
-    assert(value!.forSetter);
-    assert(
-        _mixedInSetter == null,
-        "Mixed in setter already set to $_mixedInSetter, "
-        "trying to set it to $value.");
-    _mixedInSetter = value;
-  }
-
-  List<ClassMember>? get implementedMembers => _implementedMembers;
-
-  void addImplementedMember(ClassMember value) {
-    assert(!value.forSetter);
-    _implementedMembers ??= <ClassMember>[];
-    _implementedMembers!.add(value);
-  }
-
-  List<ClassMember>? get implementedSetters => _implementedSetters;
-
-  void addImplementedSetter(ClassMember value) {
-    assert(value.forSetter);
-    _implementedSetters ??= <ClassMember>[];
-    _implementedSetters!.add(value);
-  }
-
-  @override
-  String toString() {
-    StringBuffer sb = new StringBuffer();
-    String comma = '';
-    sb.write('Tuple(');
-    if (_declaredMember != null) {
-      sb.write(comma);
-      sb.write('declaredMember=');
-      sb.write(_declaredMember);
-      comma = ',';
-    }
-    if (_declaredSetter != null) {
-      sb.write(comma);
-      sb.write('declaredSetter=');
-      sb.write(_declaredSetter);
-      comma = ',';
-    }
-    if (_mixedInMember != null) {
-      sb.write(comma);
-      sb.write('mixedInMember=');
-      sb.write(_mixedInMember);
-      comma = ',';
-    }
-    if (_mixedInSetter != null) {
-      sb.write(comma);
-      sb.write('mixedInSetter=');
-      sb.write(_mixedInSetter);
-      comma = ',';
-    }
-    if (_extendedMember != null) {
-      sb.write(comma);
-      sb.write('extendedMember=');
-      sb.write(_extendedMember);
-      comma = ',';
-    }
-    if (_extendedSetter != null) {
-      sb.write(comma);
-      sb.write('extendedSetter=');
-      sb.write(_extendedSetter);
-      comma = ',';
-    }
-    if (_implementedMembers != null) {
-      sb.write(comma);
-      sb.write('implementedMembers=');
-      sb.write(_implementedMembers);
-      comma = ',';
-    }
-    if (_implementedSetters != null) {
-      sb.write(comma);
-      sb.write('implementedSetters=');
-      sb.write(_implementedSetters);
-      comma = ',';
-    }
-    sb.write(')');
-    return sb.toString();
-  }
-}
-
-abstract class ClassMember {
-  Name get name;
-  bool get isStatic;
-  bool get isField;
-  bool get isAssignable;
-  bool get isSetter;
-  bool get isGetter;
-  bool get isFinal;
-  bool get isConst;
-  bool get forSetter;
-
-  /// Returns `true` if this member corresponds to a declaration in the source
-  /// code.
-  bool get isSourceDeclaration;
-
-  /// Returns `true` if this member is a field, getter or setter.
-  bool get isProperty;
-
-  /// Computes the [Member] node resulting from this class member.
-  Member getMember(ClassHierarchyBuilder hierarchy);
-
-  /// Returns the member [Covariance] for this class member.
-  Covariance getCovariance(ClassHierarchyBuilder hierarchy);
-
-  bool get isDuplicate;
-  String get fullName;
-  String get fullNameForErrors;
-  ClassBuilder get classBuilder;
-
-  /// Returns `true` if this class member is declared in Object from dart:core.
-  bool isObjectMember(ClassBuilder objectClass);
-  Uri get fileUri;
-  int get charOffset;
-
-  /// Returns `true` if this class member is an interface member.
-  bool get isAbstract;
-
-  /// Returns `true` if this member doesn't corresponds to a declaration in the
-  /// source code.
-  bool get isSynthesized;
-
-  // If `true` this member is not part of the interface but only part of the
-  // class members.
-  //
-  // This is `true` for instance for synthesized fields added for the late
-  // lowering.
-  bool get isInternalImplementation;
-
-  /// Returns `true` if this member is composed from a list of class members
-  /// accessible through [declarations].
-  bool get hasDeclarations;
-
-  /// If [hasDeclaration] is `true`, this returns the list of class members
-  /// from which this class member is composed.
-  ///
-  /// This is used in [unfoldDeclarations] to retrieve all underlying member
-  /// source declarations, and in [toSet] to retrieve all members used for
-  /// this class member wrt. certain level of the hierarchy.
-  /// TODO(johnniwinther): Can the use of [toSet] be replaced with a direct
-  /// use of [declarations]?
-  List<ClassMember> get declarations;
-
-  /// The interface member corresponding to this member.
-  ///
-  /// If this member is declared on the source, the interface member is
-  /// the member itself. For instance
-  ///
-  ///     abstract class Class {
-  ///        void concreteMethod() {}
-  ///        void abstractMethod();
-  ///     }
-  ///
-  /// the interface members for `concreteMethod` and `abstractMethod` are the
-  /// members themselves.
-  ///
-  /// If this member is a synthesized interface member, the
-  /// interface member is the member itself. For instance
-  ///
-  ///     abstract class Interface1 {
-  ///        void method() {}
-  ///     }
-  ///     abstract class Interface2 {
-  ///        void method() {}
-  ///     }
-  ///     abstract class Class implements Interface1, Interface2 {}
-  ///
-  /// the interface member for `method` in `Class` is the synthesized interface
-  /// member created for the implemented members `Interface1.method` and
-  /// `Interface2.method`.
-  ///
-  /// If this member is a concrete member that implements an interface member,
-  /// the interface member is the implemented interface member. For instance
-  ///
-  ///     class Super {
-  ///        void method() {}
-  ///     }
-  ///     class Interface {
-  ///        void method() {}
-  ///     }
-  ///     class Class extends Super implements Interface {}
-  ///
-  /// the interface member for `Super.method` implementing `method` in `Class`
-  /// is the synthesized interface member created for the implemented members
-  /// `Super.method` and `Interface.method`.
-  ClassMember get interfaceMember;
-
-  void inferType(ClassHierarchyBuilder hierarchy);
-  void registerOverrideDependency(Set<ClassMember> overriddenMembers);
-
-  /// Returns `true` if this has the same underlying declaration as [other].
-  ///
-  /// This is used for avoiding unnecessary checks and can this trivially
-  /// return `false`.
-  bool isSameDeclaration(ClassMember other);
-}
-
-bool hasSameSignature(FunctionNode a, FunctionNode b) {
-  List<TypeParameter> aTypeParameters = a.typeParameters;
-  List<TypeParameter> bTypeParameters = b.typeParameters;
-  int typeParameterCount = aTypeParameters.length;
-  if (typeParameterCount != bTypeParameters.length) {
-    return false;
-  }
-  Substitution? substitution;
-  if (typeParameterCount != 0) {
-    List<DartType> types = new List<DartType>.generate(
-        typeParameterCount,
-        (int i) => new TypeParameterType.forAlphaRenaming(
-            bTypeParameters[i], aTypeParameters[i]),
-        growable: false);
-    substitution = Substitution.fromPairs(bTypeParameters, types);
-    for (int i = 0; i < typeParameterCount; i++) {
-      DartType aBound = aTypeParameters[i].bound;
-      DartType bBound = substitution.substituteType(bTypeParameters[i].bound);
-      if (aBound != bBound) {
-        return false;
-      }
-    }
-  }
-
-  if (a.requiredParameterCount != b.requiredParameterCount) {
-    return false;
-  }
-  List<VariableDeclaration> aPositionalParameters = a.positionalParameters;
-  List<VariableDeclaration> bPositionalParameters = b.positionalParameters;
-  if (aPositionalParameters.length != bPositionalParameters.length) {
-    return false;
-  }
-  for (int i = 0; i < aPositionalParameters.length; i++) {
-    VariableDeclaration aParameter = aPositionalParameters[i];
-    VariableDeclaration bParameter = bPositionalParameters[i];
-    if (aParameter.isCovariantByDeclaration !=
-        bParameter.isCovariantByDeclaration) {
-      return false;
-    }
-    DartType aType = aParameter.type;
-    DartType bType = bParameter.type;
-    if (substitution != null) {
-      bType = substitution.substituteType(bType);
-    }
-    if (aType != bType) return false;
-  }
-
-  List<VariableDeclaration> aNamedParameters = a.namedParameters;
-  List<VariableDeclaration> bNamedParameters = b.namedParameters;
-  if (aNamedParameters.length != bNamedParameters.length) {
-    return false;
-  }
-  for (int i = 0; i < aNamedParameters.length; i++) {
-    VariableDeclaration aParameter = aNamedParameters[i];
-    VariableDeclaration bParameter = bNamedParameters[i];
-    if (aParameter.isCovariantByDeclaration !=
-        bParameter.isCovariantByDeclaration) {
-      return false;
-    }
-    if (aParameter.name != bParameter.name) {
-      return false;
-    }
-    DartType aType = aParameter.type;
-    DartType bType = bParameter.type;
-    if (substitution != null) {
-      bType = substitution.substituteType(bType);
-    }
-    if (aType != bType) {
-      return false;
-    }
-  }
-
-  DartType aReturnType = a.returnType;
-  DartType bReturnType = b.returnType;
-  if (substitution != null) {
-    bReturnType = substitution.substituteType(bReturnType);
-  }
-
-  return aReturnType == bReturnType;
-}
-
-class ClassHierarchyBuilder implements ClassHierarchyBase {
-  final Map<Class, ClassHierarchyNode> nodes = <Class, ClassHierarchyNode>{};
-
-  final Map<ClassBuilder, Map<Class, Substitution>> substitutions =
-      <ClassBuilder, Map<Class, Substitution>>{};
-
-  final ClassBuilder objectClassBuilder;
-
-  final Loader loader;
-
-  final Class objectClass;
-
-  final Class futureClass;
-
-  final Class functionClass;
-
-  final List<DelayedTypeComputation> _delayedTypeComputations =
-      <DelayedTypeComputation>[];
-
-  final List<DelayedCheck> _delayedChecks = <DelayedCheck>[];
-
-  final List<ClassMember> _delayedMemberComputations = <ClassMember>[];
-
-  @override
-  final CoreTypes coreTypes;
-
-  late Types types;
-
-  ClassHierarchyBuilder(this.objectClassBuilder, this.loader, this.coreTypes)
-      : objectClass = objectClassBuilder.cls,
-        futureClass = coreTypes.futureClass,
-        functionClass = coreTypes.functionClass {
-    types = new Types(this);
-  }
-
-  void clear() {
-    nodes.clear();
-    substitutions.clear();
-    _delayedChecks.clear();
-    _delayedTypeComputations.clear();
-    _delayedMemberComputations.clear();
-  }
-
-  void registerDelayedTypeComputation(DelayedTypeComputation computation) {
-    _delayedTypeComputations.add(computation);
-  }
-
-  void registerOverrideCheck(SourceClassBuilder classBuilder,
-      ClassMember declaredMember, Set<ClassMember> overriddenMembers) {
-    _delayedChecks.add(new DelayedOverrideCheck(
-        classBuilder, declaredMember, overriddenMembers));
-  }
-
-  void registerGetterSetterCheck(
-      SourceClassBuilder classBuilder, ClassMember getter, ClassMember setter) {
-    _delayedChecks
-        .add(new DelayedGetterSetterCheck(classBuilder, getter, setter));
-  }
-
-  void registerMemberComputation(ClassMember member) {
-    _delayedMemberComputations.add(member);
-  }
-
-  List<DelayedTypeComputation> takeDelayedTypeComputations() {
-    List<DelayedTypeComputation> list = _delayedTypeComputations.toList();
-    _delayedTypeComputations.clear();
-    return list;
-  }
-
-  List<DelayedCheck> takeDelayedChecks() {
-    List<DelayedCheck> list = _delayedChecks.toList();
-    _delayedChecks.clear();
-    return list;
-  }
-
-  List<ClassMember> takeDelayedMemberComputations() {
-    List<ClassMember> list = _delayedMemberComputations.toList();
-    _delayedMemberComputations.clear();
-    return list;
-  }
-
-  void inferFieldType(SourceFieldBuilder declaredMember,
-      Iterable<ClassMember> overriddenMembers) {
-    ClassHierarchyNodeBuilder.inferFieldType(
-        this,
-        declaredMember.classBuilder as SourceClassBuilder,
-        declaredMember,
-        overriddenMembers);
-  }
-
-  void inferGetterType(SourceProcedureBuilder declaredMember,
-      Iterable<ClassMember> overriddenMembers) {
-    ClassHierarchyNodeBuilder.inferGetterType(
-        this,
-        declaredMember.classBuilder as SourceClassBuilder,
-        declaredMember,
-        overriddenMembers);
-  }
-
-  void inferSetterType(SourceProcedureBuilder declaredMember,
-      Iterable<ClassMember> overriddenMembers) {
-    ClassHierarchyNodeBuilder.inferSetterType(
-        this,
-        declaredMember.classBuilder as SourceClassBuilder,
-        declaredMember,
-        overriddenMembers);
-  }
-
-  void inferMethodType(SourceProcedureBuilder declaredMember,
-      Iterable<ClassMember> overriddenMembers) {
-    ClassHierarchyNodeBuilder.inferMethodType(
-        this,
-        declaredMember.classBuilder as SourceClassBuilder,
-        declaredMember,
-        overriddenMembers);
-  }
-
-  ClassHierarchyNode getNodeFromClassBuilder(ClassBuilder classBuilder) {
-    return nodes[classBuilder.cls] ??= new ClassHierarchyNodeBuilder(
-            this, classBuilder, substitutions[classBuilder] ??= {})
-        .build();
-  }
-
-  ClassHierarchyNode? getNodeFromTypeBuilder(TypeBuilder type) {
-    ClassBuilder? cls = getClass(type);
-    return cls == null ? null : getNodeFromClassBuilder(cls);
-  }
-
-  ClassHierarchyNode getNodeFromClass(Class cls) {
-    return nodes[cls] ??
-        getNodeFromClassBuilder(loader.computeClassBuilderFromTargetClass(cls));
-  }
-
-  Supertype? asSupertypeOf(InterfaceType subtype, Class supertype) {
-    if (subtype.classNode == supertype) {
-      return new Supertype(supertype, subtype.typeArguments);
-    }
-    ClassHierarchyNode clsNode = getNodeFromClass(subtype.classNode);
-    ClassHierarchyNode supertypeNode = getNodeFromClass(supertype);
-    List<Supertype> superclasses = clsNode.superclasses;
-    int depth = supertypeNode.depth;
-    if (depth < superclasses.length) {
-      Supertype superclass = superclasses[depth];
-      if (superclass.classNode == supertype) {
-        return Substitution.fromInterfaceType(subtype)
-            .substituteSupertype(superclass);
-      }
-    }
-    List<Supertype> superinterfaces = clsNode.interfaces;
-    for (int i = 0; i < superinterfaces.length; i++) {
-      Supertype superinterface = superinterfaces[i];
-      if (superinterface.classNode == supertype) {
-        return Substitution.fromInterfaceType(subtype)
-            .substituteSupertype(superinterface);
-      }
-    }
-    return null;
-  }
-
-  @override
-  InterfaceType getTypeAsInstanceOf(
-      InterfaceType type, Class superclass, Library clientLibrary) {
-    if (type.classNode == superclass) return type;
-    return asSupertypeOf(type, superclass)!
-        .asInterfaceType
-        .withDeclaredNullability(type.nullability);
-  }
-
-  @override
-  List<DartType>? getTypeArgumentsAsInstanceOf(
-      InterfaceType type, Class superclass) {
-    if (type.classNode == superclass) return type.typeArguments;
-    return asSupertypeOf(type, superclass)?.typeArguments;
-  }
-
-  @override
-  InterfaceType getLegacyLeastUpperBound(
-      InterfaceType type1, InterfaceType type2, Library clientLibrary) {
-    if (type1 == type2) return type1;
-
-    // LLUB(Null, List<dynamic>*) works differently for opt-in and opt-out
-    // libraries.  In opt-out libraries the legacy behavior is preserved, so
-    // LLUB(Null, List<dynamic>*) = List<dynamic>*.  In opt-out libraries the
-    // rules imply that LLUB(Null, List<dynamic>*) = List<dynamic>?.
-    if (!clientLibrary.isNonNullableByDefault) {
-      if (type1 is NullType) {
-        return type2;
-      }
-      if (type2 is NullType) {
-        return type1;
-      }
-    }
-
-    ClassHierarchyNode node1 = getNodeFromClass(type1.classNode);
-    ClassHierarchyNode node2 = getNodeFromClass(type2.classNode);
-    Set<ClassHierarchyNode> nodes1 = node1.computeAllSuperNodes(this).toSet();
-    List<ClassHierarchyNode> nodes2 = node2.computeAllSuperNodes(this);
-    List<ClassHierarchyNode> common = <ClassHierarchyNode>[];
-
-    for (int i = 0; i < nodes2.length; i++) {
-      ClassHierarchyNode node = nodes2[i];
-      // ignore: unnecessary_null_comparison
-      if (node == null) continue;
-      if (node.classBuilder.cls.isAnonymousMixin) {
-        // Never find unnamed mixin application in least upper bound.
-        continue;
-      }
-      if (nodes1.contains(node)) {
-        DartType candidate1 =
-            getTypeAsInstanceOf(type1, node.classBuilder.cls, clientLibrary);
-        DartType candidate2 =
-            getTypeAsInstanceOf(type2, node.classBuilder.cls, clientLibrary);
-        if (candidate1 == candidate2) {
-          common.add(node);
-        }
-      }
-    }
-
-    if (common.length == 1) {
-      return coreTypes.objectRawType(
-          uniteNullabilities(type1.nullability, type2.nullability));
-    }
-    common.sort(ClassHierarchyNode.compareMaxInheritancePath);
-
-    for (int i = 0; i < common.length - 1; i++) {
-      ClassHierarchyNode node = common[i];
-      if (node.maxInheritancePath != common[i + 1].maxInheritancePath) {
-        return getTypeAsInstanceOf(type1, node.classBuilder.cls, clientLibrary)
-            .withDeclaredNullability(
-                uniteNullabilities(type1.nullability, type2.nullability));
-      } else {
-        do {
-          i++;
-        } while (node.maxInheritancePath == common[i + 1].maxInheritancePath);
-      }
-    }
-    return coreTypes.objectRawType(
-        uniteNullabilities(type1.nullability, type2.nullability));
-  }
-
-  @override
-  Member? getInterfaceMember(Class cls, Name name, {bool setter: false}) {
-    return getNodeFromClass(cls)
-        .getInterfaceMember(name, setter)
-        ?.getMember(this);
-  }
-
-  ClassMember? getInterfaceClassMember(Class cls, Name name,
-      {bool setter: false}) {
-    return getNodeFromClass(cls).getInterfaceMember(name, setter);
-  }
-
-  static ClassHierarchyBuilder build(ClassBuilder objectClass,
-      List<ClassBuilder> classes, SourceLoader loader, CoreTypes coreTypes) {
-    ClassHierarchyBuilder hierarchy =
-        new ClassHierarchyBuilder(objectClass, loader, coreTypes);
-    for (int i = 0; i < classes.length; i++) {
-      ClassBuilder classBuilder = classes[i];
-      if (!classBuilder.isPatch) {
-        hierarchy.nodes[classBuilder.cls] = new ClassHierarchyNodeBuilder(
-                hierarchy,
-                classBuilder,
-                hierarchy.substitutions[classBuilder] ??= {})
-            .build();
-      } else {
-        // TODO(ahe): Merge the injected members of patch into the hierarchy
-        // node of `cls.origin`.
-      }
-    }
-    return hierarchy;
-  }
-
-  void computeTypes() {
-    List<DelayedTypeComputation> typeComputations =
-        takeDelayedTypeComputations();
-    for (int i = 0; i < typeComputations.length; i++) {
-      typeComputations[i].compute(this);
-    }
-  }
-}
-
-class ClassHierarchyNodeBuilder {
-  final ClassHierarchyBuilder hierarchy;
-
-  final ClassBuilder classBuilder;
-
-  bool hasNoSuchMethod = false;
-
-  final Map<Class, Substitution> substitutions;
-
-  ClassHierarchyNodeBuilder(
-      this.hierarchy, this.classBuilder, this.substitutions);
-
-  ClassBuilder get objectClass => hierarchy.objectClassBuilder;
-
-  bool get shouldModifyKernel =>
-      classBuilder.library.loader == hierarchy.loader;
-
-  ClassMember? checkInheritanceConflict(ClassMember a, ClassMember b) {
-    if (a.isStatic || a.isProperty != b.isProperty) {
-      reportInheritanceConflict(a, b);
-      return a;
-    }
-    return null;
-  }
-
-  static void inferMethodType(
-      ClassHierarchyBuilder hierarchy,
-      SourceClassBuilder classBuilder,
-      SourceProcedureBuilder declaredMember,
-      Iterable<ClassMember> overriddenMembers) {
-    assert(!declaredMember.isGetter && !declaredMember.isSetter);
-    if (declaredMember.classBuilder == classBuilder &&
-        (declaredMember.returnType == null ||
-            declaredMember.formals != null &&
-                declaredMember.formals!
-                    .any((parameter) => parameter.type == null))) {
-      Procedure declaredProcedure = declaredMember.member as Procedure;
-      FunctionNode declaredFunction = declaredProcedure.function;
-      List<TypeParameter> declaredTypeParameters =
-          declaredFunction.typeParameters;
-      List<VariableDeclaration> declaredPositional =
-          declaredFunction.positionalParameters;
-      List<VariableDeclaration> declaredNamed =
-          declaredFunction.namedParameters;
-      declaredNamed = declaredNamed.toList()..sort(compareNamedParameters);
-
-      DartType? inferredReturnType;
-      Map<FormalParameterBuilder, DartType?> inferredParameterTypes = {};
-
-      Set<ClassMember> overriddenMemberSet =
-          toSet(classBuilder, overriddenMembers);
-      CombinedClassMemberSignature combinedMemberSignature =
-          new CombinedClassMemberSignature(
-              hierarchy, classBuilder, overriddenMemberSet.toList(),
-              forSetter: false);
-      FunctionType? combinedMemberSignatureType = combinedMemberSignature
-              .getCombinedSignatureTypeInContext(declaredTypeParameters)
-          as FunctionType?;
-
-      bool cantInferReturnType = false;
-      List<FormalParameterBuilder>? cantInferParameterTypes;
-
-      if (declaredMember.returnType == null) {
-        if (combinedMemberSignatureType == null) {
-          inferredReturnType = const InvalidType();
-          cantInferReturnType = true;
-        } else {
-          inferredReturnType = combinedMemberSignatureType.returnType;
-        }
-      }
-      if (declaredMember.formals != null) {
-        for (int i = 0; i < declaredPositional.length; i++) {
-          FormalParameterBuilder declaredParameter = declaredMember.formals![i];
-          if (declaredParameter.type != null) {
-            continue;
-          }
-
-          DartType? inferredParameterType;
-          if (combinedMemberSignatureType == null) {
-            inferredParameterType = const InvalidType();
-            cantInferParameterTypes ??= [];
-            cantInferParameterTypes.add(declaredParameter);
-          } else if (i <
-              combinedMemberSignatureType.positionalParameters.length) {
-            inferredParameterType =
-                combinedMemberSignatureType.positionalParameters[i];
-          }
-          inferredParameterTypes[declaredParameter] = inferredParameterType;
-        }
-
-        Map<String, DartType>? namedParameterTypes;
-        for (int i = declaredPositional.length;
-            i < declaredMember.formals!.length;
-            i++) {
-          FormalParameterBuilder declaredParameter = declaredMember.formals![i];
-          if (declaredParameter.type != null) {
-            continue;
-          }
-
-          DartType? inferredParameterType;
-          if (combinedMemberSignatureType == null) {
-            inferredParameterType = const InvalidType();
-            cantInferParameterTypes ??= [];
-            cantInferParameterTypes.add(declaredParameter);
-          } else {
-            if (namedParameterTypes == null) {
-              namedParameterTypes = {};
-              for (NamedType namedType
-                  in combinedMemberSignatureType.namedParameters) {
-                namedParameterTypes[namedType.name] = namedType.type;
-              }
-            }
-            inferredParameterType = namedParameterTypes[declaredParameter.name];
-          }
-          inferredParameterTypes[declaredParameter] = inferredParameterType;
-        }
-      }
-
-      if ((cantInferReturnType && cantInferParameterTypes != null) ||
-          (cantInferParameterTypes != null &&
-              cantInferParameterTypes.length > 1)) {
-        reportCantInferTypes(
-            classBuilder, declaredMember, hierarchy, overriddenMembers);
-      } else if (cantInferReturnType) {
-        reportCantInferReturnType(
-            classBuilder, declaredMember, hierarchy, overriddenMembers);
-      } else if (cantInferParameterTypes != null) {
-        reportCantInferParameterType(classBuilder,
-            cantInferParameterTypes.single, hierarchy, overriddenMembers);
-      }
-
-      if (declaredMember.returnType == null) {
-        inferredReturnType ??= const DynamicType();
-        declaredFunction.returnType = inferredReturnType;
-      }
-      if (declaredMember.formals != null) {
-        for (FormalParameterBuilder declaredParameter
-            in declaredMember.formals!) {
-          if (declaredParameter.type == null) {
-            DartType inferredParameterType =
-                inferredParameterTypes[declaredParameter] ??
-                    const DynamicType();
-            declaredParameter.variable!.type = inferredParameterType;
-          }
-        }
-      }
-    }
-  }
-
-  void inferMethodSignature(ClassHierarchyBuilder hierarchy,
-      ClassMember declaredMember, Iterable<ClassMember> overriddenMembers) {
-    assert(!declaredMember.isGetter && !declaredMember.isSetter);
-    // Trigger computation of method type.
-    Procedure declaredProcedure =
-        declaredMember.getMember(hierarchy) as Procedure;
-    for (ClassMember overriddenMember
-        in toSet(declaredMember.classBuilder, overriddenMembers)) {
-      Covariance covariance = overriddenMember.getCovariance(hierarchy);
-      covariance.applyCovariance(declaredProcedure);
-    }
-  }
-
-  void inferGetterSignature(ClassHierarchyBuilder hierarchy,
-      ClassMember declaredMember, Iterable<ClassMember> overriddenMembers) {
-    assert(declaredMember.isGetter);
-    // Trigger computation of the getter type.
-    declaredMember.getMember(hierarchy);
-    // Otherwise nothing to do. Getters have no variance.
-  }
-
-  void inferSetterSignature(ClassHierarchyBuilder hierarchy,
-      ClassMember declaredMember, Iterable<ClassMember> overriddenMembers) {
-    assert(declaredMember.isSetter);
-    // Trigger computation of the getter type.
-    Procedure declaredSetter = declaredMember.getMember(hierarchy) as Procedure;
-    for (ClassMember overriddenMember
-        in toSet(declaredMember.classBuilder, overriddenMembers)) {
-      Covariance covariance = overriddenMember.getCovariance(hierarchy);
-      covariance.applyCovariance(declaredSetter);
-    }
-  }
-
-  static void inferGetterType(
-      ClassHierarchyBuilder hierarchy,
-      SourceClassBuilder classBuilder,
-      SourceProcedureBuilder declaredMember,
-      Iterable<ClassMember> overriddenMembers) {
-    assert(declaredMember.isGetter);
-    if (declaredMember.classBuilder == classBuilder &&
-        declaredMember.returnType == null) {
-      DartType? inferredType;
-      overriddenMembers = toSet(classBuilder, overriddenMembers);
-
-      List<ClassMember> overriddenGetters = [];
-      List<ClassMember> overriddenSetters = [];
-      for (ClassMember overriddenMember in overriddenMembers) {
-        if (overriddenMember.forSetter) {
-          overriddenSetters.add(overriddenMember);
-        } else {
-          overriddenGetters.add(overriddenMember);
-        }
-      }
-
-      void inferFrom(List<ClassMember> members, {required bool forSetter}) {
-        // ignore: unnecessary_null_comparison
-        assert(forSetter != null);
-        CombinedClassMemberSignature combinedMemberSignature =
-            new CombinedClassMemberSignature(hierarchy, classBuilder, members,
-                forSetter: forSetter);
-        DartType? combinedMemberSignatureType =
-            combinedMemberSignature.combinedMemberSignatureType;
-        if (combinedMemberSignatureType == null) {
-          inferredType = const InvalidType();
-          reportCantInferReturnType(
-              classBuilder, declaredMember, hierarchy, members);
-        } else {
-          inferredType = combinedMemberSignatureType;
-        }
-      }
-
-      if (overriddenGetters.isNotEmpty) {
-        // 1) The return type of a getter, parameter type of a setter or type
-        // of a field which overrides/implements only one or more getters is
-        // inferred to be the return type of the combined member signature of
-        // said getter in the direct superinterfaces.
-
-        // 2) The return type of a getter which overrides/implements both a
-        // setter and a getter is inferred to be the return type of the
-        // combined member signature of said getter in the direct
-        // superinterfaces.
-        inferFrom(overriddenGetters, forSetter: false);
-      } else {
-        // The return type of a getter, parameter type of a setter or type of
-        // a field which overrides/implements only one or more setters is
-        // inferred to be the parameter type of the combined member signature
-        // of said setter in the direct superinterfaces.
-        inferFrom(overriddenSetters, forSetter: true);
-      }
-
-      declaredMember.procedure.function.returnType =
-          inferredType ?? const DynamicType();
-    }
-  }
-
-  static void inferSetterType(
-      ClassHierarchyBuilder hierarchy,
-      SourceClassBuilder classBuilder,
-      SourceProcedureBuilder declaredMember,
-      Iterable<ClassMember> overriddenMembers) {
-    assert(declaredMember.isSetter);
-    FormalParameterBuilder parameter = declaredMember.formals!.first;
-    if (declaredMember.classBuilder == classBuilder && parameter.type == null) {
-      DartType? inferredType;
-
-      overriddenMembers = toSet(classBuilder, overriddenMembers);
-
-      List<ClassMember> overriddenGetters = [];
-      List<ClassMember> overriddenSetters = [];
-      for (ClassMember overriddenMember in overriddenMembers) {
-        if (overriddenMember.forSetter) {
-          overriddenSetters.add(overriddenMember);
-        } else {
-          overriddenGetters.add(overriddenMember);
-        }
-      }
-
-      void inferFrom(List<ClassMember> members, {required bool forSetter}) {
-        // ignore: unnecessary_null_comparison
-        assert(forSetter != null);
-        CombinedClassMemberSignature combinedMemberSignature =
-            new CombinedClassMemberSignature(hierarchy, classBuilder, members,
-                forSetter: forSetter);
-        DartType? combinedMemberSignatureType =
-            combinedMemberSignature.combinedMemberSignatureType;
-        if (combinedMemberSignatureType == null) {
-          inferredType = const InvalidType();
-          reportCantInferReturnType(
-              classBuilder, declaredMember, hierarchy, members);
-        } else {
-          inferredType = combinedMemberSignatureType;
-        }
-      }
-
-      if (overriddenSetters.isNotEmpty) {
-        // 1) The return type of a getter, parameter type of a setter or type
-        // of a field which overrides/implements only one or more setters is
-        // inferred to be the parameter type of the combined member signature
-        // of said setter in the direct superinterfaces.
-        //
-        // 2) The parameter type of a setter which overrides/implements both a
-        // setter and a getter is inferred to be the parameter type of the
-        // combined member signature of said setter in the direct
-        // superinterfaces.
-        inferFrom(overriddenSetters, forSetter: true);
-      } else {
-        // The return type of a getter, parameter type of a setter or type of
-        // a field which overrides/implements only one or more getters is
-        // inferred to be the return type of the combined member signature of
-        // said getter in the direct superinterfaces.
-        inferFrom(overriddenGetters, forSetter: false);
-      }
-
-      parameter.variable!.type = inferredType ?? const DynamicType();
-    }
-  }
-
-  /// Merge the [inheritedType] with the currently [inferredType] using
-  /// nnbd-top-merge or legacy-top-merge depending on whether [classBuilder] is
-  /// defined in an opt-in or opt-out library. If the types could not be merged
-  /// `null` is returned and an error should be reported by the caller.
-  static DartType? mergeTypeInLibrary(
-      ClassHierarchyBuilder hierarchy,
-      ClassBuilder classBuilder,
-      DartType? inferredType,
-      DartType inheritedType) {
-    if (classBuilder.library.isNonNullableByDefault) {
-      if (inferredType == null) {
-        return inheritedType;
-      } else {
-        return nnbdTopMerge(
-            hierarchy.coreTypes,
-            norm(hierarchy.coreTypes, inferredType),
-            norm(hierarchy.coreTypes, inheritedType));
-      }
-    } else {
-      inheritedType = legacyErasure(inheritedType);
-      if (inferredType == null) {
-        return inheritedType;
-      } else {
-        if (inferredType is DynamicType &&
-            inheritedType == hierarchy.coreTypes.objectLegacyRawType) {
-          return inferredType;
-        } else if (inheritedType is DynamicType &&
-            inferredType == hierarchy.coreTypes.objectLegacyRawType) {
-          return inheritedType;
-        }
-        if (inferredType != inheritedType) {
-          return null;
-        }
-        return inferredType;
-      }
-    }
-  }
-
-  /// Infers the field type of [fieldBuilder] based on [overriddenMembers].
-  static void inferFieldType(
-      ClassHierarchyBuilder hierarchy,
-      SourceClassBuilder classBuilder,
-      SourceFieldBuilder fieldBuilder,
-      Iterable<ClassMember> overriddenMembers) {
-    if (fieldBuilder.classBuilder == classBuilder &&
-        fieldBuilder.type == null) {
-      DartType? inferredType;
-
-      overriddenMembers = toSet(classBuilder, overriddenMembers);
-      List<ClassMember> overriddenGetters = [];
-      List<ClassMember> overriddenSetters = [];
-      for (ClassMember overriddenMember in overriddenMembers) {
-        if (overriddenMember.forSetter) {
-          overriddenSetters.add(overriddenMember);
-        } else {
-          overriddenGetters.add(overriddenMember);
-        }
-      }
-
-      DartType? inferFrom(List<ClassMember> members,
-          {required bool forSetter}) {
-        // ignore: unnecessary_null_comparison
-        assert(forSetter != null);
-        CombinedClassMemberSignature combinedMemberSignature =
-            new CombinedClassMemberSignature(hierarchy, classBuilder, members,
-                forSetter: forSetter);
-        return combinedMemberSignature.combinedMemberSignatureType;
-      }
-
-      DartType? combinedMemberSignatureType;
-      if (fieldBuilder.isAssignable &&
-          overriddenGetters.isNotEmpty &&
-          overriddenSetters.isNotEmpty) {
-        // The type of a non-final field which overrides/implements both a
-        // setter and a getter is inferred to be the parameter type of the
-        // combined member signature of said setter in the direct
-        // superinterfaces, if this type is the same as the return type of the
-        // combined member signature of said getter in the direct
-        // superinterfaces. If the types are not the same then inference fails
-        // with an error.
-        DartType? getterType = inferFrom(overriddenGetters, forSetter: false);
-        DartType? setterType = inferFrom(overriddenSetters, forSetter: true);
-        if (getterType == setterType) {
-          combinedMemberSignatureType = getterType;
-        }
-      } else if (overriddenGetters.isNotEmpty) {
-        // 1) The return type of a getter, parameter type of a setter or type
-        // of a field which overrides/implements only one or more getters is
-        // inferred to be the return type of the combined member signature of
-        // said getter in the direct superinterfaces.
-        //
-        // 2) The type of a final field which overrides/implements both a
-        // setter and a getter is inferred to be the return type of the
-        // combined member signature of said getter in the direct
-        // superinterfaces.
-        combinedMemberSignatureType =
-            inferFrom(overriddenGetters, forSetter: false);
-      } else {
-        // The return type of a getter, parameter type of a setter or type of
-        // a field which overrides/implements only one or more setters is
-        // inferred to be the parameter type of the combined member signature
-        // of said setter in the direct superinterfaces.
-        combinedMemberSignatureType =
-            inferFrom(overriddenSetters, forSetter: true);
-      }
-
-      if (combinedMemberSignatureType == null) {
-        inferredType = const InvalidType();
-        reportCantInferFieldType(classBuilder, fieldBuilder, overriddenMembers);
-      } else {
-        inferredType = combinedMemberSignatureType;
-      }
-
-      fieldBuilder.fieldType = inferredType;
-    }
-  }
-
-  /// Infers the field signature of [declaredMember] based on
-  /// [overriddenMembers].
-  void inferFieldSignature(ClassHierarchyBuilder hierarchy,
-      ClassMember declaredMember, Iterable<ClassMember> overriddenMembers) {
-    Field declaredField = declaredMember.getMember(hierarchy) as Field;
-    for (ClassMember overriddenMember
-        in toSet(declaredMember.classBuilder, overriddenMembers)) {
-      Covariance covariance = overriddenMember.getCovariance(hierarchy);
-      covariance.applyCovariance(declaredField);
-    }
-  }
-
-  void reportInheritanceConflict(ClassMember a, ClassMember b) {
-    String name = a.fullNameForErrors;
-    if (a.classBuilder != b.classBuilder) {
-      if (a.classBuilder == classBuilder) {
-        classBuilder.addProblem(
-            messageDeclaredMemberConflictsWithInheritedMember,
-            a.charOffset,
-            name.length,
-            context: <LocatedMessage>[
-              messageDeclaredMemberConflictsWithInheritedMemberCause
-                  .withLocation(b.fileUri, b.charOffset, name.length)
-            ]);
-      } else if (b.classBuilder == classBuilder) {
-        classBuilder.addProblem(
-            messageDeclaredMemberConflictsWithInheritedMember,
-            b.charOffset,
-            name.length,
-            context: <LocatedMessage>[
-              messageDeclaredMemberConflictsWithInheritedMemberCause
-                  .withLocation(a.fileUri, a.charOffset, name.length)
-            ]);
-      } else {
-        classBuilder.addProblem(messageInheritedMembersConflict,
-            classBuilder.charOffset, classBuilder.fullNameForErrors.length,
-            context: _inheritedConflictContext(a, b));
-      }
-    } else if (a.isStatic != b.isStatic) {
-      ClassMember staticMember;
-      ClassMember instanceMember;
-      if (a.isStatic) {
-        staticMember = a;
-        instanceMember = b;
-      } else {
-        staticMember = b;
-        instanceMember = a;
-      }
-      classBuilder.library.addProblem(messageStaticAndInstanceConflict,
-          staticMember.charOffset, name.length, staticMember.fileUri,
-          context: <LocatedMessage>[
-            messageStaticAndInstanceConflictCause.withLocation(
-                instanceMember.fileUri, instanceMember.charOffset, name.length)
-          ]);
-    } else {
-      // This message can be reported twice (when merging localMembers with
-      // classSetters, or localSetters with classMembers). By ensuring that
-      // we always report the one with higher charOffset as the duplicate,
-      // the message duplication logic ensures that we only report this
-      // problem once.
-      ClassMember existing;
-      ClassMember duplicate;
-      assert(a.fileUri == b.fileUri);
-      if (a.charOffset < b.charOffset) {
-        existing = a;
-        duplicate = b;
-      } else {
-        existing = b;
-        duplicate = a;
-      }
-      classBuilder.library.addProblem(
-          templateDuplicatedDeclaration.withArguments(name),
-          duplicate.charOffset,
-          name.length,
-          duplicate.fileUri,
-          context: <LocatedMessage>[
-            templateDuplicatedDeclarationCause.withArguments(name).withLocation(
-                existing.fileUri, existing.charOffset, name.length)
-          ]);
-    }
-  }
-
-  ClassHierarchyNode build() {
-    assert(!classBuilder.isPatch);
-    ClassHierarchyNode? supernode;
-    if (objectClass != classBuilder.origin) {
-      supernode =
-          hierarchy.getNodeFromTypeBuilder(classBuilder.supertypeBuilder!);
-      if (supernode == null) {
-        supernode = hierarchy.getNodeFromClassBuilder(objectClass);
-      }
-      // ignore: unnecessary_null_comparison
-      assert(supernode != null);
-    }
-
-    /// Set to `true` if the class needs interfaces, that is, if it has any
-    /// members where the interface member is different from its corresponding
-    /// class members.
-    ///
-    /// This is an optimization to avoid unnecessary computation of interface
-    /// members.
-    bool hasInterfaces = false;
-
-    Map<Name, Tuple> memberMap = {};
-
-    Scope scope = classBuilder.scope;
-
-    for (Builder builder in scope.localMembers) {
-      MemberBuilder memberBuilder = builder as MemberBuilder;
-      for (ClassMember classMember in memberBuilder.localMembers) {
-        if (classMember.isAbstract) {
-          hasInterfaces = true;
-        }
-        Tuple? tuple = memberMap[classMember.name];
-        if (tuple == null) {
-          memberMap[classMember.name] = new Tuple.declareMember(classMember);
-        } else {
-          tuple.declaredMember = classMember;
-        }
-      }
-      for (ClassMember classMember in memberBuilder.localSetters) {
-        if (classMember.isAbstract) {
-          hasInterfaces = true;
-        }
-        Tuple? tuple = memberMap[classMember.name];
-        if (tuple == null) {
-          memberMap[classMember.name] = new Tuple.declareSetter(classMember);
-        } else {
-          tuple.declaredSetter = classMember;
-        }
-      }
-    }
-
-    for (MemberBuilder memberBuilder in scope.localSetters) {
-      for (ClassMember classMember in memberBuilder.localMembers) {
-        if (classMember.isAbstract) {
-          hasInterfaces = true;
-        }
-        Tuple? tuple = memberMap[classMember.name];
-        if (tuple == null) {
-          memberMap[classMember.name] = new Tuple.declareMember(classMember);
-        } else {
-          tuple.declaredMember = classMember;
-        }
-      }
-      for (ClassMember classMember in memberBuilder.localSetters) {
-        if (classMember.isAbstract) {
-          hasInterfaces = true;
-        }
-        Tuple? tuple = memberMap[classMember.name];
-        if (tuple == null) {
-          memberMap[classMember.name] = new Tuple.declareSetter(classMember);
-        } else {
-          tuple.declaredSetter = classMember;
-        }
-      }
-    }
-
-    if (classBuilder.isMixinApplication) {
-      TypeBuilder mixedInTypeBuilder = classBuilder.mixedInTypeBuilder!;
-      TypeDeclarationBuilder mixin = mixedInTypeBuilder.declaration!;
-      inferMixinApplication();
-      while (mixin.isNamedMixinApplication) {
-        ClassBuilder named = mixin as ClassBuilder;
-        mixedInTypeBuilder = named.mixedInTypeBuilder!;
-        mixin = mixedInTypeBuilder.declaration!;
-      }
-      if (mixin is TypeAliasBuilder) {
-        TypeAliasBuilder aliasBuilder = mixin;
-        NamedTypeBuilder namedBuilder = mixedInTypeBuilder as NamedTypeBuilder;
-        mixin = aliasBuilder.unaliasDeclaration(namedBuilder.arguments,
-            isUsedAsClass: true,
-            usedAsClassCharOffset: namedBuilder.charOffset,
-            usedAsClassFileUri: namedBuilder.fileUri)!;
-      }
-      if (mixin is ClassBuilder) {
-        scope = mixin.scope.computeMixinScope();
-
-        for (Builder builder in scope.localMembers) {
-          MemberBuilder memberBuilder = builder as MemberBuilder;
-          for (ClassMember classMember in memberBuilder.localMembers) {
-            if (classMember.isAbstract) {
-              hasInterfaces = true;
-            }
-            Tuple? tuple = memberMap[classMember.name];
-            if (tuple == null) {
-              memberMap[classMember.name] = new Tuple.mixInMember(classMember);
-            } else {
-              tuple.mixedInMember = classMember;
-            }
-          }
-          for (ClassMember classMember in memberBuilder.localSetters) {
-            if (classMember.isAbstract) {
-              hasInterfaces = true;
-            }
-            Tuple? tuple = memberMap[classMember.name];
-            if (tuple == null) {
-              memberMap[classMember.name] = new Tuple.mixInSetter(classMember);
-            } else {
-              tuple.mixedInSetter = classMember;
-            }
-          }
-        }
-
-        for (MemberBuilder memberBuilder in scope.localSetters) {
-          for (ClassMember classMember in memberBuilder.localMembers) {
-            if (classMember.isAbstract) {
-              hasInterfaces = true;
-            }
-            Tuple? tuple = memberMap[classMember.name];
-            if (tuple == null) {
-              memberMap[classMember.name] = new Tuple.mixInMember(classMember);
-            } else {
-              tuple.mixedInMember = classMember;
-            }
-          }
-          for (ClassMember classMember in memberBuilder.localSetters) {
-            if (classMember.isAbstract) {
-              hasInterfaces = true;
-            }
-            Tuple? tuple = memberMap[classMember.name];
-            if (tuple == null) {
-              memberMap[classMember.name] = new Tuple.mixInSetter(classMember);
-            } else {
-              tuple.mixedInSetter = classMember;
-            }
-          }
-        }
-      }
-    }
-
-    List<Supertype> superclasses;
-
-    List<Supertype> interfaces;
-
-    int maxInheritancePath;
-
-    void extend(Map<Name, ClassMember>? superClassMembers) {
-      if (superClassMembers == null) return;
-      for (MapEntry<Name, ClassMember> entry in superClassMembers.entries) {
-        Name name = entry.key;
-        ClassMember superClassMember = entry.value;
-        Tuple? tuple = memberMap[name];
-        if (tuple != null) {
-          if (superClassMember.forSetter) {
-            tuple.extendedSetter = superClassMember;
-          } else {
-            tuple.extendedMember = superClassMember;
-          }
-        } else {
-          if (superClassMember.forSetter) {
-            memberMap[name] = new Tuple.extendSetter(superClassMember);
-          } else {
-            memberMap[name] = new Tuple.extendMember(superClassMember);
-          }
-        }
-      }
-    }
-
-    void implement(Map<Name, ClassMember>? superInterfaceMembers) {
-      if (superInterfaceMembers == null) return;
-      for (MapEntry<Name, ClassMember> entry in superInterfaceMembers.entries) {
-        Name name = entry.key;
-        ClassMember superInterfaceMember = entry.value;
-        Tuple? tuple = memberMap[name];
-        if (tuple != null) {
-          if (superInterfaceMember.forSetter) {
-            tuple.addImplementedSetter(superInterfaceMember);
-          } else {
-            tuple.addImplementedMember(superInterfaceMember);
-          }
-        } else {
-          if (superInterfaceMember.forSetter) {
-            memberMap[superInterfaceMember.name] =
-                new Tuple.implementSetter(superInterfaceMember);
-          } else {
-            memberMap[superInterfaceMember.name] =
-                new Tuple.implementMember(superInterfaceMember);
-          }
-        }
-      }
-    }
-
-    if (supernode == null) {
-      // This should be Object.
-      superclasses = new List<Supertype>.filled(0, dummySupertype);
-      interfaces = new List<Supertype>.filled(0, dummySupertype);
-      maxInheritancePath = 0;
-    } else {
-      maxInheritancePath = supernode.maxInheritancePath + 1;
-
-      superclasses = new List<Supertype>.filled(
-          supernode.superclasses.length + 1, dummySupertype);
-      Supertype? supertype = classBuilder.supertypeBuilder!.buildSupertype(
-          classBuilder.library, classBuilder.charOffset, classBuilder.fileUri);
-      if (supertype == null) {
-        // If the superclass is not an interface type we use Object instead.
-        // A similar normalization is performed on [supernode] above.
-        supertype =
-            new Supertype(hierarchy.coreTypes.objectClass, const <DartType>[]);
-      }
-      superclasses.setRange(0, superclasses.length - 1,
-          substSupertypes(supertype, supernode.superclasses));
-      superclasses[superclasses.length - 1] = supertype;
-      if (!classBuilder.library.isNonNullableByDefault &&
-          supernode.classBuilder.library.isNonNullableByDefault) {
-        for (int i = 0; i < superclasses.length; i++) {
-          superclasses[i] = legacyErasureSupertype(superclasses[i]);
-        }
-      }
-
-      List<TypeBuilder>? directInterfaceBuilders =
-          ignoreFunction(classBuilder.interfaceBuilders);
-      if (classBuilder.isMixinApplication) {
-        if (directInterfaceBuilders == null) {
-          directInterfaceBuilders = <TypeBuilder>[
-            classBuilder.mixedInTypeBuilder!
-          ];
-        } else {
-          directInterfaceBuilders = <TypeBuilder>[
-            classBuilder.mixedInTypeBuilder!
-          ]..addAll(directInterfaceBuilders);
-        }
-      }
-
-      List<Supertype> superclassInterfaces = supernode.interfaces;
-      // ignore: unnecessary_null_comparison
-      if (superclassInterfaces != null) {
-        superclassInterfaces = substSupertypes(supertype, superclassInterfaces);
-      }
-
-      extend(supernode.classMemberMap);
-      extend(supernode.classSetterMap);
-
-      if (supernode.interfaceMemberMap != null ||
-          supernode.interfaceSetterMap != null) {
-        hasInterfaces = true;
-      }
-
-      if (hasInterfaces) {
-        implement(supernode.interfaceMemberMap ?? supernode.classMemberMap);
-        implement(supernode.interfaceSetterMap ?? supernode.classSetterMap);
-      }
-
-      if (directInterfaceBuilders != null) {
-        for (int i = 0; i < directInterfaceBuilders.length; i++) {
-          ClassHierarchyNode? interfaceNode =
-              hierarchy.getNodeFromTypeBuilder(directInterfaceBuilders[i]);
-          if (interfaceNode != null) {
-            hasInterfaces = true;
-
-            implement(interfaceNode.interfaceMemberMap ??
-                interfaceNode.classMemberMap);
-            implement(interfaceNode.interfaceSetterMap ??
-                interfaceNode.classSetterMap);
-          }
-        }
-
-        interfaces = <Supertype>[];
-        // ignore: unnecessary_null_comparison
-        if (superclassInterfaces != null) {
-          for (int i = 0; i < superclassInterfaces.length; i++) {
-            addInterface(interfaces, superclasses, superclassInterfaces[i]);
-          }
-        }
-
-        for (int i = 0; i < directInterfaceBuilders.length; i++) {
-          Supertype? directInterface = directInterfaceBuilders[i]
-              .buildSupertype(classBuilder.library, classBuilder.charOffset,
-                  classBuilder.fileUri);
-          if (directInterface != null) {
-            addInterface(interfaces, superclasses, directInterface);
-            ClassHierarchyNode interfaceNode =
-                hierarchy.getNodeFromClass(directInterface.classNode);
-            // ignore: unnecessary_null_comparison
-            if (interfaceNode != null) {
-              if (maxInheritancePath < interfaceNode.maxInheritancePath + 1) {
-                maxInheritancePath = interfaceNode.maxInheritancePath + 1;
-              }
-
-              List<Supertype> types =
-                  substSupertypes(directInterface, interfaceNode.superclasses);
-              for (int i = 0; i < types.length; i++) {
-                addInterface(interfaces, superclasses, types[i]);
-              }
-              // ignore: unnecessary_null_comparison
-              if (interfaceNode.interfaces != null) {
-                List<Supertype> types =
-                    substSupertypes(directInterface, interfaceNode.interfaces);
-                for (int i = 0; i < types.length; i++) {
-                  addInterface(interfaces, superclasses, types[i]);
-                }
-              }
-            }
-          }
-        }
-        // ignore: unnecessary_null_comparison
-      } else if (superclassInterfaces != null &&
-          !classBuilder.library.isNonNullableByDefault &&
-          supernode.classBuilder.library.isNonNullableByDefault) {
-        interfaces = <Supertype>[];
-        for (int i = 0; i < superclassInterfaces.length; i++) {
-          addInterface(interfaces, superclasses, superclassInterfaces[i]);
-        }
-      } else {
-        interfaces = superclassInterfaces;
-      }
-    }
-
-    for (Supertype superclass in superclasses) {
-      recordSupertype(superclass);
-    }
-    // ignore: unnecessary_null_comparison
-    if (interfaces != null) {
-      for (Supertype superinterface in interfaces) {
-        recordSupertype(superinterface);
-      }
-    }
-
-    /// Members (excluding setters) declared in [cls] or its superclasses. This
-    /// includes static methods of [cls], but not its superclasses.
-    Map<Name, ClassMember> classMemberMap = {};
-
-    /// Setters declared in [cls] or its superclasses. This includes static
-    /// setters of [cls], but not its superclasses.
-    Map<Name, ClassMember> classSetterMap = {};
-
-    /// Members (excluding setters) inherited from interfaces. This contains no
-    /// static members. If no interfaces are implemented by this class or its
-    /// superclasses this is identical to [classMemberMap] and we do not store
-    /// it in the [ClassHierarchyNode].
-    Map<Name, ClassMember>? interfaceMemberMap = {};
-
-    /// Setters inherited from interfaces. This contains no static setters. If
-    /// no interfaces are implemented by this class or its superclasses this is
-    /// identical to [classSetterMap] and we do not store it in the
-    /// [ClassHierarchyNode].
-    Map<Name, ClassMember>? interfaceSetterMap = {};
-
-    /// Map for members declared in this class to the members that they
-    /// override. This is used for checking valid overrides and to ensure that
-    /// override inference correctly propagates inferred types through the
-    /// class hierarchy.
-    Map<ClassMember, Set<ClassMember>> declaredOverridesMap = {};
-
-    /// In case this class is a mixin application, this maps members declared in
-    /// the mixin to the members that they override. This is used for checking
-    /// valid overrides but _not_ as for [declaredOverridesMap] for override
-    /// inference.
-    Map<ClassMember, Set<ClassMember>> mixinApplicationOverridesMap = {};
-
-    /// In case this class is concrete, this maps concrete members that are
-    /// inherited into this class to the members they should override to validly
-    /// implement the interface of this class.
-    Map<ClassMember, Set<ClassMember>> inheritedImplementsMap = {};
-
-    /// In case this class is concrete, this holds the interface members
-    /// without a corresponding class member. These are either reported as
-    /// missing implementations or trigger insertion of noSuchMethod forwarders.
-    List<ClassMember>? abstractMembers = [];
-
-    ClassHierarchyNodeDataForTesting? dataForTesting;
-    if (retainDataForTesting) {
-      dataForTesting = new ClassHierarchyNodeDataForTesting(
-          abstractMembers,
-          declaredOverridesMap,
-          mixinApplicationOverridesMap,
-          inheritedImplementsMap);
-    }
-
-    /// Registers that the current class has an interface member without a
-    /// corresponding class member.
-    ///
-    /// This is used to report missing implementation or, in the case the class
-    /// has a user defined concrete noSuchMethod, to insert noSuchMethod
-    /// forwarders. (Currently, insertion of forwarders is handled elsewhere.)
-    ///
-    /// For instance:
-    ///
-    ///    abstract class Interface {
-    ///      method();
-    ///    }
-    ///    class Class1 implements Interface {
-    ///      // Missing implementation for `Interface.method`.
-    ///    }
-    ///    class Class2 implements Interface {
-    ///      noSuchMethod(_) {}
-    ///      // A noSuchMethod forwarder is added for `Interface.method`.
-    ///    }
-    ///
-    void registerAbstractMember(ClassMember abstractMember) {
-      if (!abstractMember.isInternalImplementation) {
-        /// If `isInternalImplementation` is `true`, the member is synthesized
-        /// implementation that does not require implementation in other
-        /// classes.
-        ///
-        /// This is for instance used for late lowering where
-        ///
-        ///    class Interface {
-        ///      late int? field;
-        ///    }
-        ///    class Class implements Interface {
-        ///      int? field;
-        ///    }
-        ///
-        /// is encoded as
-        ///
-        ///    class Interface {
-        ///      bool _#field#isSet = false;
-        ///      int? _#field = null;
-        ///      int? get field => _#field#isSet ? _#field : throw ...;
-        ///      void set field(int? value) { ... }
-        ///    }
-        ///    class Class implements Interface {
-        ///      int? field;
-        ///    }
-        ///
-        /// and `Class` should not be required to implement
-        /// `Interface._#field#isSet` and `Interface._#field`.
-        abstractMembers.add(abstractMember);
-      }
-    }
-
-    /// Registers that [inheritedMember] should be checked to validly override
-    /// [overrides].
-    ///
-    /// This is needed in the case where a concrete member is inherited into
-    /// a concrete subclass. For instance:
-    ///
-    ///    class Super {
-    ///      void method() {}
-    ///    }
-    ///    abstract class Interface {
-    ///      void method();
-    ///    }
-    ///    class Class extends Super implements Interface {}
-    ///
-    /// Here `Super.method` must be checked to be a valid implementation for
-    /// `Interface.method` by being a valid override of it.
-    void registerInheritedImplements(
-        ClassMember inheritedMember, Set<ClassMember> overrides,
-        {required ClassMember aliasForTesting}) {
-      if (classBuilder is SourceClassBuilder) {
-        assert(
-            inheritedMember.classBuilder != classBuilder,
-            "Only inherited members can implement by inheritance: "
-            "${inheritedMember}");
-        inheritedImplementsMap[inheritedMember] = overrides;
-        // ignore: unnecessary_null_comparison
-        if (dataForTesting != null && aliasForTesting != null) {
-          dataForTesting.aliasMap[aliasForTesting] = inheritedMember;
-        }
-      }
-    }
-
-    /// Returns `true` if the current class is from an opt-out library and
-    /// [classMember] is from an opt-in library.
-    ///
-    /// In this case a member signature needs to be inserted to show the
-    /// legacy erased type of the interface member. For instance:
-    ///
-    ///    // Opt-in library:
-    ///    class Super {
-    ///      int? method(int i) {}
-    ///    }
-    ///    // Opt-out library:
-    ///    class Class extends Super {
-    ///      // A member signature is inserted:
-    ///      // int* method(int* i);
-    ///    }
-    ///
-    bool needsMemberSignatureFor(ClassMember classMember) {
-      return !classBuilder.library.isNonNullableByDefault &&
-          classMember.classBuilder.library.isNonNullableByDefault;
-    }
-
-    memberMap.forEach((Name name, Tuple tuple) {
-      /// The computation starts by sanitizing the members. Conflicts between
-      /// methods and properties (getters/setters) or between static and
-      /// instance members are reported. Conflicting members and members
-      /// overridden by duplicates are removed.
-      ///
-      /// For this [definingGetable] and [definingSetable] hold the first member
-      /// of its kind found among declared, mixed in, extended and implemented
-      /// members.
-      ///
-      /// Conflicts between [definingGetable] and [definingSetable] are reported
-      /// afterwards.
-
-      ClassMember? definingGetable;
-      ClassMember? definingSetable;
-
-      ClassMember? declaredGetable = tuple.declaredMember;
-      if (declaredGetable != null) {
-        /// class Class {
-        ///   method() {}
-        /// }
-        definingGetable = declaredGetable;
-      }
-      ClassMember? declaredSetable = tuple.declaredSetter;
-      if (declaredSetable != null) {
-        /// class Class {
-        ///   set setter(value) {}
-        /// }
-        definingSetable = declaredSetable;
-      }
-
-      ClassMember? mixedInGetable;
-      ClassMember? tupleMixedInMember = tuple.mixedInMember;
-      if (tupleMixedInMember != null &&
-          !tupleMixedInMember.isStatic &&
-          !tupleMixedInMember.isDuplicate &&
-          !tupleMixedInMember.isSynthesized) {
-        /// We treat
-        ///
-        ///   opt-in:
-        ///   class Interface {
-        ///     method3() {}
-        ///   }
-        ///   opt-out:
-        ///   class Mixin implements Interface {
-        ///     static method1() {}
-        ///     method2() {}
-        ///     method2() {}
-        ///     /*member-signature*/ method3() {}
-        ///   }
-        ///   class Class with Mixin {}
-        ///
-        /// as
-        ///
-        ///   class Mixin {}
-        ///   class Class with Mixin {}
-        ///
-        /// Note that skipped synthetic getable 'method3' is still included
-        /// in the implemented getables, but its type will not define the type
-        /// when mixed in. For instance
-        ///
-        ///   opt-in:
-        ///   abstract class Interface {
-        ///     num get getter;
-        ///   }
-        ///   opt-out:
-        ///   abstract class Super {
-        ///     int get getter;
-        ///   }
-        ///   abstract class Mixin implements Interface {
-        ///     /*member-signature*/ num get getter;
-        ///   }
-        ///   abstract class Class extends Super with Mixin {}
-        ///
-        /// Here the type of `Class.getter` should not be defined from the
-        /// synthetic member signature `Mixin.getter` but as a combined member
-        /// signature of `Super.getter` and `Mixin.getter`, resulting in type
-        /// `int` instead of `num`.
-        if (definingGetable == null) {
-          /// class Mixin {
-          ///   method() {}
-          /// }
-          /// class Class with Mixin {}
-          definingGetable = mixedInGetable = tupleMixedInMember;
-        } else if (!definingGetable.isDuplicate) {
-          // This case is currently unreachable from source code since classes
-          // cannot both declare and mix in members. From dill, this can occur
-          // but should not conflicting members.
-          //
-          // The case is handled for consistency.
-          if (definingGetable.isStatic ||
-              definingGetable.isProperty != tupleMixedInMember.isProperty) {
-            reportInheritanceConflict(definingGetable, tupleMixedInMember);
-          } else {
-            mixedInGetable = tupleMixedInMember;
-          }
-        }
-      }
-      ClassMember? mixedInSetable;
-      ClassMember? tupleMixedInSetter = tuple.mixedInSetter;
-      if (tupleMixedInSetter != null &&
-          !tupleMixedInSetter.isStatic &&
-          !tupleMixedInSetter.isDuplicate &&
-          !tupleMixedInSetter.isSynthesized) {
-        /// We treat
-        ///
-        ///   class Mixin {
-        ///     static set setter1(value) {}
-        ///     set setter2(value) {}
-        ///     set setter2(value) {}
-        ///     /*member-signature*/ setter3() {}
-        ///   }
-        ///   class Class with Mixin {}
-        ///
-        /// as
-        ///
-        ///   class Mixin {}
-        ///   class Class with Mixin {}
-        ///
-        /// Note that skipped synthetic setable 'setter3' is still included
-        /// in the implemented setables, but its type will not define the type
-        /// when mixed in. For instance
-        ///
-        ///   opt-in:
-        ///   abstract class Interface {
-        ///     void set setter(int value);
-        ///   }
-        ///   opt-out:
-        ///   abstract class Super {
-        ///     void set setter(num value);
-        ///   }
-        ///   abstract class Mixin implements Interface {
-        ///     /*member-signature*/ num get getter;
-        ///   }
-        ///   abstract class Class extends Super with Mixin {}
-        ///
-        /// Here the type of `Class.setter` should not be defined from the
-        /// synthetic member signature `Mixin.setter` but as a combined member
-        /// signature of `Super.setter` and `Mixin.setter`, resulting in type
-        /// `num` instead of `int`.
-        if (definingSetable == null) {
-          /// class Mixin {
-          ///   set setter(value) {}
-          /// }
-          /// class Class with Mixin {}
-          definingSetable = mixedInSetable = tupleMixedInSetter;
-        } else if (!definingSetable.isDuplicate) {
-          if (definingSetable.isStatic ||
-              definingSetable.isProperty != tupleMixedInSetter.isProperty) {
-            reportInheritanceConflict(definingSetable, tupleMixedInSetter);
-          } else {
-            mixedInSetable = tupleMixedInSetter;
-          }
-        }
-      }
-
-      ClassMember? extendedGetable;
-      ClassMember? tupleExtendedMember = tuple.extendedMember;
-      if (tupleExtendedMember != null &&
-          !tupleExtendedMember.isStatic &&
-          !tupleExtendedMember.isDuplicate) {
-        /// We treat
-        ///
-        ///   class Super {
-        ///     static method1() {}
-        ///     method2() {}
-        ///     method2() {}
-        ///   }
-        ///   class Class extends Super {}
-        ///
-        /// as
-        ///
-        ///   class Super {}
-        ///   class Class extends Super {}
-        ///
-        if (definingGetable == null) {
-          /// class Super {
-          ///   method() {}
-          /// }
-          /// class Class extends Super {}
-          definingGetable = extendedGetable = tupleExtendedMember;
-        } else if (!definingGetable.isDuplicate) {
-          if (definingGetable.isStatic ||
-              definingGetable.isProperty != tupleExtendedMember.isProperty) {
-            ///   class Super {
-            ///     method() {}
-            ///   }
-            ///   class Class extends Super {
-            ///     static method() {}
-            ///   }
-            ///
-            /// or
-            ///
-            ///   class Super {
-            ///     method() {}
-            ///   }
-            ///   class Class extends Super {
-            ///     get getter => 0;
-            ///   }
-            reportInheritanceConflict(definingGetable, tupleExtendedMember);
-          } else {
-            extendedGetable = tupleExtendedMember;
-          }
-        }
-      }
-      ClassMember? extendedSetable;
-      ClassMember? tupleExtendedSetter = tuple.extendedSetter;
-      if (tupleExtendedSetter != null &&
-          !tupleExtendedSetter.isStatic &&
-          !tupleExtendedSetter.isDuplicate) {
-        /// We treat
-        ///
-        ///   class Super {
-        ///     static set setter1(value) {}
-        ///     set setter2(value) {}
-        ///     set setter2(value) {}
-        ///   }
-        ///   class Class extends Super {}
-        ///
-        /// as
-        ///
-        ///   class Super {}
-        ///   class Class extends Super {}
-        ///
-        if (definingSetable == null) {
-          /// class Super {
-          ///   set setter(value) {}
-          /// }
-          /// class Class extends Super {}
-          definingSetable = extendedSetable = tupleExtendedSetter;
-        } else if (!definingSetable.isDuplicate) {
-          if (definingSetable.isStatic ||
-              definingSetable.isProperty != tupleExtendedSetter.isProperty) {
-            reportInheritanceConflict(definingSetable, tupleExtendedSetter);
-          } else {
-            extendedSetable = tupleExtendedSetter;
-          }
-        }
-      }
-
-      // TODO(johnniwinther): Remove extended and mixed in members/setters
-      // from implemented members/setters. Mixin applications always implement
-      // the mixin class leading to unnecessary interface members.
-      List<ClassMember>? implementedGetables;
-      List<ClassMember>? tupleImplementedMembers = tuple.implementedMembers;
-      if (tupleImplementedMembers != null &&
-          // Skip implemented members if we already have a duplicate.
-          !(definingGetable != null && definingGetable.isDuplicate)) {
-        for (int i = 0; i < tupleImplementedMembers.length; i++) {
-          ClassMember? implementedGetable = tupleImplementedMembers[i];
-          if (implementedGetable.isStatic || implementedGetable.isDuplicate) {
-            /// We treat
-            ///
-            ///   class Interface {
-            ///     static method1() {}
-            ///     method2() {}
-            ///     method2() {}
-            ///   }
-            ///   class Class implements Interface {}
-            ///
-            /// as
-            ///
-            ///   class Interface {}
-            ///   class Class implements Interface {}
-            ///
-            implementedGetable = null;
-          } else {
-            if (definingGetable == null) {
-              /// class Interface {
-              ///   method() {}
-              /// }
-              /// class Class implements Interface {}
-              definingGetable = implementedGetable;
-            } else if (definingGetable.isStatic ||
-                definingGetable.isProperty != implementedGetable.isProperty) {
-              ///   class Interface {
-              ///     method() {}
-              ///   }
-              ///   class Class implements Interface {
-              ///     static method() {}
-              ///   }
-              ///
-              /// or
-              ///
-              ///   class Interface {
-              ///     method() {}
-              ///   }
-              ///   class Class implements Interface {
-              ///     get getter => 0;
-              ///   }
-              reportInheritanceConflict(definingGetable, implementedGetable);
-              implementedGetable = null;
-            }
-          }
-          if (implementedGetable == null) {
-            // On the first skipped member we add all previous.
-            implementedGetables ??= tupleImplementedMembers.take(i).toList();
-          } else if (implementedGetables != null) {
-            // If already skipping members we add [implementedGetable]
-            // explicitly.
-            implementedGetables.add(implementedGetable);
-          }
-        }
-        if (implementedGetables == null) {
-          // No members were skipped so we use the full list.
-          implementedGetables = tupleImplementedMembers;
-        } else if (implementedGetables.isEmpty) {
-          // No members were included.
-          implementedGetables = null;
-        }
-      }
-
-      List<ClassMember>? implementedSetables;
-      List<ClassMember>? tupleImplementedSetters = tuple.implementedSetters;
-      if (tupleImplementedSetters != null &&
-          // Skip implemented setters if we already have a duplicate.
-          !(definingSetable != null && definingSetable.isDuplicate)) {
-        for (int i = 0; i < tupleImplementedSetters.length; i++) {
-          ClassMember? implementedSetable = tupleImplementedSetters[i];
-          if (implementedSetable.isStatic || implementedSetable.isDuplicate) {
-            /// We treat
-            ///
-            ///   class Interface {
-            ///     static set setter1(value) {}
-            ///     set setter2(value) {}
-            ///     set setter2(value) {}
-            ///   }
-            ///   class Class implements Interface {}
-            ///
-            /// as
-            ///
-            ///   class Interface {}
-            ///   class Class implements Interface {}
-            ///
-            implementedSetable = null;
-          } else {
-            if (definingSetable == null) {
-              /// class Interface {
-              ///   set setter(value) {}
-              /// }
-              /// class Class implements Interface {}
-              definingSetable = implementedSetable;
-            } else if (definingSetable.isStatic ||
-                definingSetable.isProperty != implementedSetable.isProperty) {
-              /// class Interface {
-              ///   set setter(value) {}
-              /// }
-              /// class Class implements Interface {
-              ///   static set setter(value) {}
-              /// }
-              reportInheritanceConflict(definingSetable, implementedSetable);
-              implementedSetable = null;
-            }
-          }
-          if (implementedSetable == null) {
-            // On the first skipped setter we add all previous.
-            implementedSetables ??= tupleImplementedSetters.take(i).toList();
-          } else if (implementedSetables != null) {
-            // If already skipping setters we add [implementedSetable]
-            // explicitly.
-            implementedSetables.add(implementedSetable);
-          }
-        }
-        if (implementedSetables == null) {
-          // No setters were skipped so we use the full list.
-          implementedSetables = tupleImplementedSetters;
-        } else if (implementedSetables.isEmpty) {
-          // No setters were included.
-          implementedSetables = null;
-        }
-      }
-
-      if (definingGetable != null && definingSetable != null) {
-        if (definingGetable.isStatic != definingSetable.isStatic ||
-            definingGetable.isProperty != definingSetable.isProperty) {
-          reportInheritanceConflict(definingGetable, definingSetable);
-          // TODO(johnniwinther): Should we remove [definingSetable]? If we
-          // leave it in this conflict will also be reported in subclasses. If
-          // we remove it, any write to the setable will be unresolved.
-        }
-      }
-
-      // TODO(johnniwinther): Handle declared members together with mixed in
-      // members. This should only occur from .dill, though.
-      if (mixedInGetable != null) {
-        declaredGetable = null;
-      }
-      if (mixedInSetable != null) {
-        declaredSetable = null;
-      }
-
-      /// Set to `true` if declared members have been registered in
-      /// [registerDeclaredOverride] or [registerMixedInOverride].
-      bool hasDeclaredMembers = false;
-
-      /// Declared methods, getters and setters registered in
-      /// [registerDeclaredOverride].
-      ClassMember? declaredMethod;
-      List<ClassMember>? declaredProperties;
-
-      /// Declared methods, getters and setters registered in
-      /// [registerDeclaredOverride].
-      ClassMember? mixedInMethod;
-      List<ClassMember>? mixedInProperties;
-
-      /// Registers that [declaredMember] overrides extended and implemented
-      /// members.
-      ///
-      /// Getters and setters share overridden members so the registration
-      /// of override relations is performed after the interface members have
-      /// been computed.
-      ///
-      /// Declared members must be checked for valid override of the overridden
-      /// members _and_ must register an override dependency with the overridden
-      /// members so that override inference can propagate inferred types
-      /// correctly. For instance:
-      ///
-      ///    class Super {
-      ///      int get property => 42;
-      ///    }
-      ///    class Class extends Super {
-      ///      void set property(value) {}
-      ///    }
-      ///
-      /// Here the parameter type of the setter `Class.property` must be
-      /// inferred from the type of the getter `Super.property`.
-      void registerDeclaredOverride(ClassMember declaredMember,
-          {ClassMember? aliasForTesting}) {
-        if (classBuilder is SourceClassBuilder && !declaredMember.isStatic) {
-          assert(
-              declaredMember.isSourceDeclaration &&
-                  declaredMember.classBuilder == classBuilder,
-              "Only declared members can override: ${declaredMember}");
-          hasDeclaredMembers = true;
-          if (declaredMember.isProperty) {
-            declaredProperties ??= [];
-            declaredProperties!.add(declaredMember);
-          } else {
-            assert(
-                declaredMethod == null,
-                "Multiple methods unexpectedly declared: "
-                "${declaredMethod} and ${declaredMember}.");
-            declaredMethod = declaredMember;
-          }
-          if (dataForTesting != null && aliasForTesting != null) {
-            dataForTesting.aliasMap[aliasForTesting] = declaredMember;
-          }
-        }
-      }
-
-      /// Registers that [mixedMember] overrides extended and implemented
-      /// members through application.
-      ///
-      /// Getters and setters share overridden members so the registration
-      /// of override relations in performed after the interface members have
-      /// been computed.
-      ///
-      /// Declared mixed in members must be checked for valid override of the
-      /// overridden members but _not_ register an override dependency with the
-      /// overridden members. This is in contrast to declared members. For
-      /// instance:
-      ///
-      ///    class Super {
-      ///      int get property => 42;
-      ///    }
-      ///    class Mixin {
-      ///      void set property(value) {}
-      ///    }
-      ///    class Class = Super with Mixin;
-      ///
-      /// Here the parameter type of the setter `Mixin.property` must _not_ be
-      /// inferred from the type of the getter `Super.property`, but should
-      /// instead default to `dynamic`.
-      void registerMixedInOverride(ClassMember mixedInMember,
-          {ClassMember? aliasForTesting}) {
-        assert(mixedInMember.classBuilder != classBuilder,
-            "Only mixin members can override by application: ${mixedInMember}");
-        if (classBuilder is SourceClassBuilder) {
-          hasDeclaredMembers = true;
-          if (mixedInMember.isProperty) {
-            mixedInProperties ??= [];
-            mixedInProperties!.add(mixedInMember);
-          } else {
-            assert(
-                mixedInMethod == null,
-                "Multiple methods unexpectedly declared in mixin: "
-                "${mixedInMethod} and ${mixedInMember}.");
-            mixedInMethod = mixedInMember;
-          }
-          if (dataForTesting != null && aliasForTesting != null) {
-            dataForTesting.aliasMap[aliasForTesting] = mixedInMember;
-          }
-        }
-      }
-
-      /// Computes the class and interface members for a method, getter, or
-      /// setter in the current [tuple].
-      ///
-      /// [definingMember] is the member which defines whether the computation
-      /// is for a method, a getter or a setter.
-      /// [declaredMember] is the member declared in the current class, if any.
-      /// [mixedInMember] is the member declared in a mixin that is mixed into
-      /// the current current class, if any.
-      /// [extendedMember] is the member inherited from the super class.
-      /// [implementedMembers] are the members inherited from the super
-      /// interfaces, if none this is `null`.
-      ///
-      /// The computed class and interface members are added to [classMemberMap]
-      /// and [interfaceMemberMap], respectively.
-      ClassMember? computeMembers(
-          {required ClassMember definingMember,
-          required ClassMember? declaredMember,
-          required ClassMember? mixedInMember,
-          required ClassMember? extendedMember,
-          required List<ClassMember>? implementedMembers,
-          required Map<Name, ClassMember> classMemberMap,
-          required Map<Name, ClassMember>? interfaceMemberMap}) {
-        ClassMember? classMember;
-        ClassMember? interfaceMember;
-
-        if (mixedInMember != null) {
-          if (mixedInMember.isAbstract) {
-            ///    class Mixin {
-            ///      method();
-            ///    }
-            ///    class Class = Object with Mixin;
-
-            /// Interface members from the extended, mixed in, and implemented
-            /// members define the combined member signature.
-            Set<ClassMember> interfaceMembers = {};
-
-            if (extendedMember != null) {
-              ///    class Super {
-              ///      method() {}
-              ///    }
-              ///    class Mixin {
-              ///      method();
-              ///    }
-              ///    class Class = Super with Mixin;
-              interfaceMembers.add(extendedMember.interfaceMember);
-            }
-
-            interfaceMembers.add(mixedInMember);
-
-            if (implementedMembers != null) {
-              ///    class Interface {
-              ///      method() {}
-              ///    }
-              ///    class Mixin {
-              ///      method();
-              ///    }
-              ///    class Class = Object with Mixin implements Interface;
-              interfaceMembers.addAll(implementedMembers);
-            }
-
-            /// We always create a synthesized interface member, even in the
-            /// case of [interfaceMembers] being a singleton, to insert the
-            /// abstract mixin stub.
-            interfaceMember = new SynthesizedInterfaceMember(
-                classBuilder, name, interfaceMembers.toList(),
-                superClassMember: extendedMember,
-                // [definingMember] and [mixedInMember] are always the same
-                // here. Use the latter here and the former below to show the
-                // the member is canonical _because_ its the mixed in member and
-                // it defines the isProperty/forSetter properties _because_ it
-                // is the defining member.
-                canonicalMember: mixedInMember,
-                mixedInMember: mixedInMember,
-                isProperty: definingMember.isProperty,
-                forSetter: definingMember.forSetter,
-                shouldModifyKernel: shouldModifyKernel);
-            hierarchy.registerMemberComputation(interfaceMember);
-
-            if (extendedMember != null) {
-              ///    class Super {
-              ///      method() {}
-              ///    }
-              ///    class Mixin {
-              ///      method();
-              ///    }
-              ///    class Class = Super with Mixin;
-              ///
-              /// The concrete extended member is the class member but might
-              /// be overwritten by a concrete forwarding stub:
-              ///
-              ///    class Super {
-              ///      method(int i) {}
-              ///    }
-              ///    class Interface {
-              ///      method(covariant int i) {}
-              ///    }
-              ///    class Mixin {
-              ///      method(int i);
-              ///    }
-              ///    // A concrete forwarding stub
-              ///    //   method(covariant int i) => super.method(i);
-              ///    // will be inserted.
-              ///    class Class = Super with Mixin implements Interface;
-              ///
-              classMember = new InheritedClassMemberImplementsInterface(
-                  classBuilder, name,
-                  inheritedClassMember: extendedMember,
-                  implementedInterfaceMember: interfaceMember,
-                  forSetter: definingMember.forSetter,
-                  isProperty: definingMember.isProperty);
-              hierarchy.registerMemberComputation(classMember);
-              if (!classBuilder.isAbstract) {
-                registerInheritedImplements(extendedMember, {interfaceMember},
-                    aliasForTesting: classMember);
-              }
-            } else if (!classBuilder.isAbstract) {
-              ///    class Mixin {
-              ///      method(); // Missing implementation.
-              ///    }
-              ///    class Class = Object with Mixin;
-              registerAbstractMember(interfaceMember);
-            }
-
-            assert(!mixedInMember.isSynthesized);
-            if (!mixedInMember.isSynthesized) {
-              /// Members declared in the mixin must override extended and
-              /// implemented members.
-              ///
-              /// When loading from .dill the mixed in member might be
-              /// synthesized, for instance a member signature or forwarding
-              /// stub, and this should not be checked to override the extended
-              /// and implemented members:
-              ///
-              ///    // Opt-out library, from source:
-              ///    class Mixin {}
-              ///    // Opt-out library, from .dill:
-              ///    class Mixin {
-              ///      ...
-              ///      String* toString(); // member signature
-              ///    }
-              ///    // Opt-out library, from source:
-              ///    class Class = Object with Mixin;
-              ///    // Mixin.toString should not be checked to override
-              ///    // Object.toString.
-              ///
-              registerMixedInOverride(mixedInMember,
-                  aliasForTesting: interfaceMember);
-            }
-          } else {
-            assert(!mixedInMember.isAbstract);
-
-            ///    class Mixin {
-            ///      method() {}
-            ///    }
-            ///    class Class = Object with Mixin;
-            ///
-
-            /// Interface members from the extended, mixed in, and implemented
-            /// members define the combined member signature.
-            Set<ClassMember> interfaceMembers = {};
-
-            if (extendedMember != null) {
-              ///    class Super {
-              ///      method() {}
-              ///    }
-              ///    class Mixin {
-              ///      method() {}
-              ///    }
-              ///    class Class = Super with Mixin;
-              interfaceMembers.add(extendedMember.interfaceMember);
-            }
-
-            interfaceMembers.add(mixedInMember);
-
-            if (implementedMembers != null) {
-              ///    class Interface {
-              ///      method() {}
-              ///    }
-              ///    class Mixin {
-              ///      method() {}
-              ///    }
-              ///    class Class = Object with Mixin implements Interface;
-              interfaceMembers.addAll(implementedMembers);
-            }
-
-            /// We always create a synthesized interface member, even in the
-            /// case of [interfaceMembers] being a singleton, to insert the
-            /// concrete mixin stub.
-            interfaceMember = new SynthesizedInterfaceMember(
-                classBuilder, name, interfaceMembers.toList(),
-                superClassMember: mixedInMember,
-                // [definingMember] and [mixedInMember] are always the same
-                // here. Use the latter here and the former below to show the
-                // the member is canonical _because_ its the mixed in member and
-                // it defines the isProperty/forSetter properties _because_ it
-                // is the defining member.
-                canonicalMember: mixedInMember,
-                mixedInMember: mixedInMember,
-                isProperty: definingMember.isProperty,
-                forSetter: definingMember.forSetter,
-                shouldModifyKernel: shouldModifyKernel);
-            hierarchy.registerMemberComputation(interfaceMember);
-
-            /// The concrete mixed in member is the class member but will
-            /// be overwritten by a concrete mixin stub:
-            ///
-            ///    class Mixin {
-            ///       method() {}
-            ///    }
-            ///    // A concrete mixin stub
-            ///    //   method() => super.method();
-            ///    // will be inserted.
-            ///    class Class = Object with Mixin;
-            ///
-            classMember = new InheritedClassMemberImplementsInterface(
-                classBuilder, name,
-                inheritedClassMember: mixedInMember,
-                implementedInterfaceMember: interfaceMember,
-                forSetter: definingMember.forSetter,
-                isProperty: definingMember.isProperty);
-            hierarchy.registerMemberComputation(classMember);
-
-            if (!classBuilder.isAbstract) {
-              ///    class Interface {
-              ///      method() {}
-              ///    }
-              ///    class Mixin {
-              ///      method() {}
-              ///    }
-              ///    class Class = Object with Mixin;
-              ///
-              /// [mixinMember] must implemented interface member.
-              registerInheritedImplements(mixedInMember, {interfaceMember},
-                  aliasForTesting: classMember);
-            }
-            assert(!mixedInMember.isSynthesized);
-            if (!mixedInMember.isSynthesized) {
-              /// Members declared in the mixin must override extended and
-              /// implemented members.
-              ///
-              /// When loading from .dill the mixed in member might be
-              /// synthesized, for instance a member signature or forwarding
-              /// stub, and this should not be checked to override the extended
-              /// and implemented members.
-              ///
-              /// These synthesized mixed in members should always be abstract
-              /// and therefore not be handled here, but we handled them here
-              /// for consistency.
-              registerMixedInOverride(mixedInMember);
-            }
-          }
-        } else if (declaredMember != null) {
-          if (declaredMember.isAbstract) {
-            ///    class Class {
-            ///      method();
-            ///    }
-            interfaceMember = declaredMember;
-
-            /// Interface members from the declared, extended, and implemented
-            /// members define the combined member signature.
-            Set<ClassMember> interfaceMembers = {};
-
-            if (extendedMember != null) {
-              ///    class Super {
-              ///      method() {}
-              ///    }
-              ///    class Class extends Super {
-              ///      method();
-              ///    }
-              interfaceMembers.add(extendedMember);
-            }
-
-            interfaceMembers.add(declaredMember);
-
-            if (implementedMembers != null) {
-              ///    class Interface {
-              ///      method() {}
-              ///    }
-              ///    class Class implements Interface {
-              ///      method();
-              ///    }
-              interfaceMembers.addAll(implementedMembers);
-            }
-
-            /// If only one member defines the interface member there is no
-            /// need for a synthesized interface member, since its result will
-            /// simply be that one member.
-            if (interfaceMembers.length > 1) {
-              ///    class Super {
-              ///      method() {}
-              ///    }
-              ///    class Interface {
-              ///      method() {}
-              ///    }
-              ///    class Class extends Super implements Interface {
-              ///      method();
-              ///    }
-              interfaceMember = new SynthesizedInterfaceMember(
-                  classBuilder, name, interfaceMembers.toList(),
-                  superClassMember: extendedMember,
-                  // [definingMember] and [declaredMember] are always the same
-                  // here. Use the latter here and the former below to show the
-                  // the member is canonical _because_ its the declared member
-                  // and it defines the isProperty/forSetter properties
-                  // _because_ it is the defining member.
-                  canonicalMember: declaredMember,
-                  isProperty: definingMember.isProperty,
-                  forSetter: definingMember.forSetter,
-                  shouldModifyKernel: shouldModifyKernel);
-              hierarchy.registerMemberComputation(interfaceMember);
-            }
-
-            if (extendedMember != null) {
-              ///    class Super {
-              ///      method() {}
-              ///    }
-              ///    class Class extends Super {
-              ///      method();
-              ///    }
-              ///
-              /// The concrete extended member is the class member but might
-              /// be overwritten by a concrete forwarding stub:
-              ///
-              ///    class Super {
-              ///      method(int i) {}
-              ///    }
-              ///    class Interface {
-              ///      method(covariant int i) {}
-              ///    }
-              ///    class Class extends Super implements Interface {
-              ///      // This will be turned into the concrete forwarding stub
-              ///      //    method(covariant int i) => super.method(i);
-              ///      method(int i);
-              ///    }
-              ///
-              classMember = new InheritedClassMemberImplementsInterface(
-                  classBuilder, name,
-                  inheritedClassMember: extendedMember,
-                  implementedInterfaceMember: interfaceMember,
-                  forSetter: definingMember.forSetter,
-                  isProperty: definingMember.isProperty);
-              hierarchy.registerMemberComputation(classMember);
-
-              if (!classBuilder.isAbstract) {
-                ///    class Super {
-                ///      method() {}
-                ///    }
-                ///    class Class extends Super {
-                ///      method();
-                ///    }
-                ///
-                /// [extendedMember] must implemented interface member.
-                registerInheritedImplements(extendedMember, {interfaceMember},
-                    aliasForTesting: classMember);
-              }
-            } else if (!classBuilder.isAbstract) {
-              ///    class Class {
-              ///      method(); // Missing implementation.
-              ///    }
-              registerAbstractMember(declaredMember);
-            }
-
-            /// The declared member must override extended and implemented
-            /// members.
-            registerDeclaredOverride(declaredMember,
-                aliasForTesting: interfaceMember);
-          } else {
-            assert(!declaredMember.isAbstract);
-
-            ///    class Class {
-            ///      method() {}
-            ///    }
-            classMember = declaredMember;
-
-            /// The declared member must override extended and implemented
-            /// members.
-            registerDeclaredOverride(declaredMember);
-          }
-        } else if (extendedMember != null) {
-          ///    class Super {
-          ///      method() {}
-          ///    }
-          ///    class Class extends Super {}
-          assert(!extendedMember.isAbstract,
-              "Abstract extended member: ${extendedMember}");
-
-          classMember = extendedMember;
-
-          if (implementedMembers != null) {
-            ///    class Super {
-            ///      method() {}
-            ///    }
-            ///    class Interface {
-            ///      method() {}
-            ///    }
-            ///    class Class extends Super implements Interface {}
-            ClassMember extendedInterfaceMember =
-                extendedMember.interfaceMember;
-
-            /// Interface members from the extended and implemented
-            /// members define the combined member signature.
-            Set<ClassMember> interfaceMembers = {extendedInterfaceMember};
-
-            // TODO(johnniwinther): The extended member might be included in
-            // a synthesized implemented member. For instance:
-            //
-            //    class Super {
-            //      void method() {}
-            //    }
-            //    class Interface {
-            //      void method() {}
-            //    }
-            //    abstract class Class extends Super implements Interface {
-            //      // Synthesized interface member of
-            //      //   {Super.method, Interface.method}
-            //    }
-            //    class Sub extends Class {
-            //      // Super.method implements Class.method =
-            //      //   {Super.method, Interface.method}
-            //      // Synthesized interface member of
-            //      //   {Super.method, Class.method}
-            //    }
-            //
-            // Maybe we should recognize this.
-            interfaceMembers.addAll(implementedMembers);
-
-            /// Normally, if only one member defines the interface member there
-            /// is no need for a synthesized interface member, since its result
-            /// will simply be that one member, but if the extended member is
-            /// from an opt-in library and the current class is from an opt-out
-            /// library we need to create a member signature:
-            ///
-            ///    // Opt-in:
-            ///    class Super {
-            ///      int? method() => null;
-            ///    }
-            ///    class Interface implements Super {}
-            ///    // Opt-out:
-            ///    class Class extends Super implements Interface {
-            ///      // Member signature added:
-            ///      int* method();
-            ///    }
-            ///
-            if (interfaceMembers.length == 1 &&
-                !needsMemberSignatureFor(extendedInterfaceMember)) {
-              ///    class Super {
-              ///      method() {}
-              ///    }
-              ///    class Interface implements Super {}
-              ///    class Class extends Super implements Interface {}
-              interfaceMember = interfaceMembers.first;
-            } else {
-              ///    class Super {
-              ///      method() {}
-              ///    }
-              ///    class Interface {
-              ///      method() {}
-              ///    }
-              ///    class Class extends Super implements Interface {}
-              interfaceMember = new SynthesizedInterfaceMember(
-                  classBuilder, name, interfaceMembers.toList(),
-                  superClassMember: extendedMember,
-                  isProperty: definingMember.isProperty,
-                  forSetter: definingMember.forSetter,
-                  shouldModifyKernel: shouldModifyKernel);
-              hierarchy.registerMemberComputation(interfaceMember);
-            }
-            if (interfaceMember == classMember) {
-              ///    class Super {
-              ///      method() {}
-              ///    }
-              ///    class Interface implements Super {}
-              ///    class Class extends Super implements Interface {}
-              ///
-              /// We keep track of whether a class needs interfaces, that is,
-              /// whether is has any members that have an interface member
-              /// different from its corresponding class member, so we set
-              /// [interfaceMember] to `null` so show that the interface member
-              /// is not needed.
-              interfaceMember = null;
-            } else {
-              ///    class Super {
-              ///      method() {}
-              ///    }
-              ///    class Interface {
-              ///      method() {}
-              ///    }
-              ///    class Class extends Super implements Interface {}
-              ///
-              /// The concrete extended member is the class member but might
-              /// be overwritten by a concrete forwarding stub:
-              ///
-              ///    class Super {
-              ///      method(int i) {}
-              ///    }
-              ///    class Interface {
-              ///      method(covariant int i) {}
-              ///    }
-              ///    class Class extends Super implements Interface {
-              ///      // A concrete forwarding stub will be created:
-              ///      //    method(covariant int i) => super.method(i);
-              ///    }
-              ///
-              classMember = new InheritedClassMemberImplementsInterface(
-                  classBuilder, name,
-                  inheritedClassMember: extendedMember,
-                  implementedInterfaceMember: interfaceMember,
-                  isProperty: definingMember.isProperty,
-                  forSetter: definingMember.forSetter);
-              hierarchy.registerMemberComputation(classMember);
-              if (!classBuilder.isAbstract) {
-                ///    class Super {
-                ///      method() {}
-                ///    }
-                ///    class Interface {
-                ///      method() {}
-                ///    }
-                ///    class Class extends Super implements Interface {}
-                registerInheritedImplements(extendedMember, {interfaceMember},
-                    aliasForTesting: classMember);
-              }
-            }
-          } else if (needsMemberSignatureFor(extendedMember)) {
-            ///    // Opt-in library:
-            ///    class Super {
-            ///      method() {}
-            ///    }
-            ///    // opt-out library:
-            ///    class Class extends Super {}
-            interfaceMember = new SynthesizedInterfaceMember(
-                classBuilder, name, [extendedMember],
-                superClassMember: extendedMember,
-                isProperty: definingMember.isProperty,
-                forSetter: definingMember.forSetter,
-                shouldModifyKernel: shouldModifyKernel);
-            hierarchy.registerMemberComputation(interfaceMember);
-
-            /// The concrete extended member is the class member and should
-            /// be able to be overwritten by a synthesized concrete member here,
-            /// but we handle the case for consistency.
-            classMember = new InheritedClassMemberImplementsInterface(
-                classBuilder, name,
-                inheritedClassMember: extendedMember,
-                implementedInterfaceMember: interfaceMember,
-                isProperty: definingMember.isProperty,
-                forSetter: definingMember.forSetter);
-            hierarchy.registerMemberComputation(classMember);
-          }
-        } else if (implementedMembers != null) {
-          ///    class Interface {
-          ///      method() {}
-          ///    }
-          ///    class Class implements Interface {}
-          Set<ClassMember> interfaceMembers = implementedMembers.toSet();
-          if (interfaceMembers.isNotEmpty) {
-            /// Normally, if only one member defines the interface member there
-            /// is no need for a synthesized interface member, since its result
-            /// will simply be that one member, but if the implemented member is
-            /// from an opt-in library and the current class is from an opt-out
-            /// library we need to create a member signature:
-            ///
-            ///    // Opt-in:
-            ///    class Interface {
-            ///      int? method() => null;
-            ///    }
-            ///    // Opt-out:
-            ///    class Class implements Interface {
-            ///      // Member signature added:
-            ///      int* method();
-            ///    }
-            ///
-            if (interfaceMembers.length == 1 &&
-                !needsMemberSignatureFor(interfaceMembers.first)) {
-              ///    class Interface {
-              ///      method() {}
-              ///    }
-              ///    class Class implements Interface {}
-              interfaceMember = interfaceMembers.first;
-            } else {
-              ///    class Interface1 {
-              ///      method() {}
-              ///    }
-              ///    class Interface2 {
-              ///      method() {}
-              ///    }
-              ///    class Class implements Interface1, Interface2 {}
-              interfaceMember = new SynthesizedInterfaceMember(
-                  classBuilder, name, interfaceMembers.toList(),
-                  isProperty: definingMember.isProperty,
-                  forSetter: definingMember.forSetter,
-                  shouldModifyKernel: shouldModifyKernel);
-              hierarchy.registerMemberComputation(interfaceMember);
-            }
-            if (!classBuilder.isAbstract) {
-              ///    class Interface {
-              ///      method() {}
-              ///    }
-              ///    class Class implements Interface {}
-              for (ClassMember abstractMember in interfaceMembers) {
-                registerAbstractMember(abstractMember);
-              }
-            }
-          }
-        }
-
-        if (interfaceMember != null) {
-          // We have an explicit interface.
-          hasInterfaces = true;
-        }
-        if (classMember != null) {
-          if (name == noSuchMethodName &&
-              !classMember.isObjectMember(objectClass)) {
-            hasNoSuchMethod = true;
-          }
-          classMemberMap[name] = classMember;
-          interfaceMember ??= classMember.interfaceMember;
-        }
-        if (interfaceMember != null) {
-          interfaceMemberMap![name] = interfaceMember;
-        }
-        return interfaceMember;
-      }
-
-      ClassMember? interfaceGetable;
-      if (definingGetable != null) {
-        interfaceGetable = computeMembers(
-            definingMember: definingGetable,
-            declaredMember: declaredGetable,
-            mixedInMember: mixedInGetable,
-            extendedMember: extendedGetable,
-            implementedMembers: implementedGetables,
-            classMemberMap: classMemberMap,
-            interfaceMemberMap: interfaceMemberMap);
-      }
-      ClassMember? interfaceSetable;
-      if (definingSetable != null) {
-        interfaceSetable = computeMembers(
-            definingMember: definingSetable,
-            declaredMember: declaredSetable,
-            mixedInMember: mixedInSetable,
-            extendedMember: extendedSetable,
-            implementedMembers: implementedSetables,
-            classMemberMap: classSetterMap,
-            interfaceMemberMap: interfaceSetterMap);
-      }
-      if (classBuilder is SourceClassBuilder) {
-        if (interfaceGetable != null &&
-            interfaceSetable != null &&
-            interfaceGetable.isProperty &&
-            interfaceSetable.isProperty &&
-            interfaceGetable.isStatic == interfaceSetable.isStatic &&
-            !interfaceGetable.isSameDeclaration(interfaceSetable)) {
-          /// We need to check that the getter type is a subtype of the setter
-          /// type. For instance
-          ///
-          ///    class Super {
-          ///       int get property1 => null;
-          ///       num get property2 => null;
-          ///    }
-          ///    class Mixin {
-          ///       void set property1(num value) {}
-          ///       void set property2(int value) {}
-          ///    }
-          ///    class Class = Super with Mixin;
-          ///
-          /// Here `Super.property1` and `Mixin.property1` form a valid getter/
-          /// setter pair in `Class` because the type of the getter
-          /// `Super.property1` is a subtype of the setter `Mixin.property1`.
-          ///
-          /// In contrast the pair `Super.property2` and `Mixin.property2` is
-          /// not a valid getter/setter in `Class` because the type of the getter
-          /// `Super.property2` is _not_ a subtype of the setter
-          /// `Mixin.property1`.
-          hierarchy.registerGetterSetterCheck(
-              classBuilder as SourceClassBuilder,
-              interfaceGetable,
-              interfaceSetable);
-        }
-      }
-      if (hasDeclaredMembers) {
-        Set<ClassMember> getableOverrides = {};
-        Set<ClassMember> setableOverrides = {};
-        if (extendedGetable != null) {
-          ///    (abstract) class Super {
-          ///      method() {}
-          ///      int get property => 0;
-          ///    }
-          ///    (abstract) class Class extends Super {
-          ///      method() {}
-          ///      set property(int value) {}
-          ///    }
-          getableOverrides.add(extendedGetable.interfaceMember);
-        }
-        if (extendedSetable != null) {
-          ///    (abstract) class Super {
-          ///      set setter(int value) {}
-          ///      set property(int value) {}
-          ///    }
-          ///    (abstract) class Class extends Super {
-          ///      set setter(int value) {}
-          ///      int get property => 0;
-          ///    }
-          setableOverrides.add(extendedSetable.interfaceMember);
-        }
-        if (implementedGetables != null) {
-          ///    (abstract) class Interface {
-          ///      method() {}
-          ///      int get property => 0;
-          ///    }
-          ///    (abstract) class Class implements Interface {
-          ///      method() {}
-          ///      set property(int value) {}
-          ///    }
-          getableOverrides.addAll(implementedGetables);
-        }
-        if (implementedSetables != null) {
-          ///    (abstract) class Interface {
-          ///      set setter(int value) {}
-          ///      set property(int value) {}
-          ///    }
-          ///    (abstract) class Class implements Interface {
-          ///      set setter(int value) {}
-          ///      int get property => 0;
-          ///    }
-          setableOverrides.addAll(implementedSetables);
-        }
-        if (getableOverrides.isNotEmpty || setableOverrides.isNotEmpty) {
-          if (declaredMethod != null && getableOverrides.isNotEmpty) {
-            ///    class Super {
-            ///      method() {}
-            ///    }
-            ///    class Class extends Super {
-            ///      method() {}
-            ///    }
-            declaredOverridesMap[declaredMethod!] = getableOverrides;
-          }
-          if (declaredProperties != null) {
-            Set<ClassMember> overrides;
-            if (declaredMethod != null) {
-              ///    class Super {
-              ///      set setter() {}
-              ///    }
-              ///    class Class extends Super {
-              ///      method() {}
-              ///    }
-              overrides = setableOverrides;
-            } else {
-              ///    class Super {
-              ///      get property => null
-              ///      void set property(value) {}
-              ///    }
-              ///    class Class extends Super {
-              ///      get property => null
-              ///      void set property(value) {}
-              ///    }
-              overrides = {...getableOverrides, ...setableOverrides};
-            }
-            if (overrides.isNotEmpty) {
-              for (ClassMember declaredMember in declaredProperties!) {
-                declaredOverridesMap[declaredMember] = overrides;
-              }
-            }
-          }
-          if (mixedInMethod != null && getableOverrides.isNotEmpty) {
-            ///    class Super {
-            ///      method() {}
-            ///    }
-            ///    class Mixin {
-            ///      method() {}
-            ///    }
-            ///    class Class = Super with Mixin;
-            mixinApplicationOverridesMap[mixedInMethod!] = getableOverrides;
-          }
-          if (mixedInProperties != null) {
-            Set<ClassMember> overrides;
-            if (mixedInMethod != null) {
-              ///    class Super {
-              ///      set setter() {}
-              ///    }
-              ///    class Mixin {
-              ///      method() {}
-              ///    }
-              ///    class Class = Super with Mixin;
-              overrides = setableOverrides;
-            } else {
-              ///    class Super {
-              ///      method() {}
-              ///    }
-              ///    class Mixin extends Super {
-              ///      method() {}
-              ///    }
-              overrides = {...getableOverrides, ...setableOverrides};
-            }
-            if (overrides.isNotEmpty) {
-              for (ClassMember mixedInMember in mixedInProperties!) {
-                mixinApplicationOverridesMap[mixedInMember] = overrides;
-              }
-            }
-          }
-        }
-      }
-    });
-
-    if (classBuilder is SourceClassBuilder) {
-      // TODO(johnniwinther): Avoid duplicate override check computations
-      //  between [declaredOverridesMap], [mixinApplicationOverridesMap] and
-      //  [inheritedImplementsMap].
-
-      // TODO(johnniwinther): Ensure that a class member is only checked to
-      // validly override another member once. Currently it can happen multiple
-      // times as an inherited implementation.
-
-      declaredOverridesMap.forEach(
-          (ClassMember classMember, Set<ClassMember> overriddenMembers) {
-        /// A declared member can inherit its type from the overridden members.
-        ///
-        /// We register this with the class member itself so the it can force
-        /// computation of type on the overridden members before determining its
-        /// own type.
-        ///
-        /// Member types can be queried at arbitrary points during top level
-        /// inference so we need to ensure that types are computed in dependency
-        /// order.
-        classMember.registerOverrideDependency(overriddenMembers);
-
-        /// Not all member type are queried during top level inference so we
-        /// register delayed computation to ensure that all types have been
-        /// computed before override checks are performed.
-        DelayedTypeComputation computation =
-            new DelayedTypeComputation(this, classMember, overriddenMembers);
-        hierarchy.registerDelayedTypeComputation(computation);
-
-        /// Declared members must be checked to validly override the
-        /// overridden members.
-        hierarchy.registerOverrideCheck(
-            classBuilder as SourceClassBuilder, classMember, overriddenMembers);
-      });
-
-      mixinApplicationOverridesMap.forEach(
-          (ClassMember classMember, Set<ClassMember> overriddenMembers) {
-        /// Declared mixed in members must be checked to validly override the
-        /// overridden members.
-        hierarchy.registerOverrideCheck(
-            classBuilder as SourceClassBuilder, classMember, overriddenMembers);
-      });
-
-      inheritedImplementsMap.forEach(
-          (ClassMember classMember, Set<ClassMember> overriddenMembers) {
-        /// Concrete members must be checked to validly override the overridden
-        /// members in concrete classes.
-        hierarchy.registerOverrideCheck(
-            classBuilder as SourceClassBuilder, classMember, overriddenMembers);
-      });
-    }
-
-    if (!hasInterfaces) {
-      /// All interface members also class members to we don't need to store
-      /// the interface members separately.
-      assert(
-          classMemberMap.length == interfaceMemberMap.length,
-          "Class/interface member mismatch. Class members: "
-          "$classMemberMap, interface members: $interfaceMemberMap.");
-      assert(
-          classSetterMap.length == interfaceSetterMap.length,
-          "Class/interface setter mismatch. Class setters: "
-          "$classSetterMap, interface setters: $interfaceSetterMap.");
-      assert(
-          classMemberMap.keys.every((Name name) =>
-              identical(classMemberMap[name], interfaceMemberMap?[name])),
-          "Class/interface member mismatch. Class members: "
-          "$classMemberMap, interface members: $interfaceMemberMap.");
-      assert(
-          classSetterMap.keys.every((Name name) =>
-              identical(classSetterMap[name], interfaceSetterMap?[name])),
-          "Class/interface setter mismatch. Class setters: "
-          "$classSetterMap, interface setters: $interfaceSetterMap.");
-      interfaceMemberMap = null;
-      interfaceSetterMap = null;
-    }
-
-    // ignore: unnecessary_null_comparison
-    if (abstractMembers != null && !classBuilder.isAbstract) {
-      if (!hasNoSuchMethod) {
-        reportMissingMembers(abstractMembers);
-      } else {
-        installNsmHandlers();
-      }
-    }
-
-    return new ClassHierarchyNode(
-        classBuilder,
-        classMemberMap,
-        classSetterMap,
-        interfaceMemberMap,
-        interfaceSetterMap,
-        superclasses,
-        interfaces,
-        maxInheritancePath,
-        hasNoSuchMethod,
-        dataForTesting);
-  }
-
-  Supertype recordSupertype(Supertype supertype) {
-    debug?.log("In ${this.classBuilder.fullNameForErrors} "
-        "recordSupertype(${supertype})");
-    Class cls = supertype.classNode;
-    List<TypeParameter> supertypeTypeParameters = cls.typeParameters;
-    if (supertypeTypeParameters.isEmpty) {
-      substitutions[cls] = Substitution.empty;
-    } else {
-      List<DartType> arguments = supertype.typeArguments;
-      List<DartType> typeArguments =
-          new List<DartType>.filled(arguments.length, dummyDartType);
-      List<TypeParameter> typeParameters =
-          new List<TypeParameter>.filled(arguments.length, dummyTypeParameter);
-      for (int i = 0; i < arguments.length; i++) {
-        typeParameters[i] = supertypeTypeParameters[i];
-        typeArguments[i] = arguments[i];
-      }
-      substitutions[cls] =
-          Substitution.fromPairs(typeParameters, typeArguments);
-    }
-    return supertype;
-  }
-
-  List<Supertype> substSupertypes(
-      Supertype supertype, List<Supertype> supertypes) {
-    List<TypeParameter> typeVariables = supertype.classNode.typeParameters;
-    if (typeVariables.isEmpty) {
-      debug?.log("In ${this.classBuilder.fullNameForErrors} "
-          "$supertypes aren't substed");
-      return supertypes;
-    }
-    Map<TypeParameter, DartType> map = <TypeParameter, DartType>{};
-    List<DartType> arguments = supertype.typeArguments;
-    for (int i = 0; i < typeVariables.length; i++) {
-      map[typeVariables[i]] = arguments[i];
-    }
-    Substitution substitution = Substitution.fromMap(map);
-    List<Supertype>? result;
-    for (int i = 0; i < supertypes.length; i++) {
-      Supertype supertype = supertypes[i];
-      Supertype substituted = substitution.substituteSupertype(supertype);
-      if (supertype != substituted) {
-        debug?.log("In ${this.classBuilder.fullNameForErrors} $supertype"
-            " -> $substituted");
-        result ??= supertypes.toList();
-        result[i] = substituted;
-      } else {
-        debug?.log("In ${this.classBuilder.fullNameForErrors} "
-            "$supertype isn't substed");
-      }
-    }
-    return result ?? supertypes;
-  }
-
-  void addInterface(List<Supertype> interfaces, List<Supertype> superclasses,
-      Supertype type) {
-    // ignore: unnecessary_null_comparison
-    if (type == null) return null;
-    if (!classBuilder.library.isNonNullableByDefault) {
-      type = legacyErasureSupertype(type);
-    }
-    ClassHierarchyNode node = hierarchy.getNodeFromClass(type.classNode);
-    // ignore: unnecessary_null_comparison
-    if (node == null) return null;
-    int depth = node.depth;
-    int myDepth = superclasses.length;
-    Supertype? superclass = depth < myDepth ? superclasses[depth] : null;
-    if (superclass != null && superclass.classNode == type.classNode) {
-      // This is a potential conflict.
-      if (classBuilder.library.isNonNullableByDefault) {
-        superclass = nnbdTopMergeSupertype(
-            hierarchy.coreTypes,
-            normSupertype(hierarchy.coreTypes, superclass),
-            normSupertype(hierarchy.coreTypes, type));
-        if (superclass == null) {
-          // This is a conflict.
-          // TODO(johnniwinther): Report errors here instead of through
-          // the computation of the [ClassHierarchy].
-          superclass = superclasses[depth];
-        } else {
-          superclasses[depth] = superclass;
-        }
-      }
-      return;
-    } else {
-      for (int i = 0; i < interfaces.length; i++) {
-        // This is a quadratic algorithm, but normally, the number of
-        // interfaces is really small.
-        Supertype? interface = interfaces[i];
-        if (interface.classNode == type.classNode) {
-          // This is a potential conflict.
-          if (classBuilder.library.isNonNullableByDefault) {
-            interface = nnbdTopMergeSupertype(
-                hierarchy.coreTypes,
-                normSupertype(hierarchy.coreTypes, interface),
-                normSupertype(hierarchy.coreTypes, type));
-            if (interface == null) {
-              // This is a conflict.
-              // TODO(johnniwinther): Report errors here instead of through
-              // the computation of the [ClassHierarchy].
-              interface = interfaces[i];
-            } else {
-              interfaces[i] = interface;
-            }
-          }
-          return;
-        }
-      }
-    }
-    interfaces.add(type);
-  }
-
-  void reportMissingMembers(List<ClassMember> abstractMembers) {
-    Map<String, LocatedMessage> contextMap = <String, LocatedMessage>{};
-    for (ClassMember declaration in unfoldDeclarations(abstractMembers)) {
-      if (isNameVisibleIn(declaration.name, classBuilder.library)) {
-        String name = declaration.fullNameForErrors;
-        String className = declaration.classBuilder.fullNameForErrors;
-        String displayName =
-            declaration.isSetter ? "$className.$name=" : "$className.$name";
-        contextMap[displayName] = templateMissingImplementationCause
-            .withArguments(displayName)
-            .withLocation(
-                declaration.fileUri, declaration.charOffset, name.length);
-      }
-    }
-    if (contextMap.isEmpty) return;
-    List<String> names = new List<String>.from(contextMap.keys)..sort();
-    List<LocatedMessage> context = <LocatedMessage>[];
-    for (int i = 0; i < names.length; i++) {
-      context.add(contextMap[names[i]]!);
-    }
-    classBuilder.addProblem(
-        templateMissingImplementationNotAbstract.withArguments(
-            classBuilder.fullNameForErrors, names),
-        classBuilder.charOffset,
-        classBuilder.fullNameForErrors.length,
-        context: context);
-  }
-
-  void installNsmHandlers() {
-    // TODO(ahe): Implement this.
-  }
-
-  void inferMixinApplication() {
-    Class cls = classBuilder.cls;
-    Supertype? mixedInType = cls.mixedInType;
-    if (mixedInType == null) return;
-    List<DartType> typeArguments = mixedInType.typeArguments;
-    if (typeArguments.isEmpty || typeArguments.first is! UnknownType) return;
-    new BuilderMixinInferrer(
-            classBuilder,
-            hierarchy.coreTypes,
-            new TypeBuilderConstraintGatherer(hierarchy,
-                mixedInType.classNode.typeParameters, cls.enclosingLibrary))
-        .infer(cls);
-    List<TypeBuilder> inferredArguments = new List<TypeBuilder>.generate(
-        typeArguments.length,
-        (int i) => hierarchy.loader.computeTypeBuilder(typeArguments[i]),
-        growable: false);
-    NamedTypeBuilder mixedInTypeBuilder =
-        classBuilder.mixedInTypeBuilder as NamedTypeBuilder;
-    mixedInTypeBuilder.arguments = inferredArguments;
-  }
-
-  /// The class Function from dart:core is supposed to be ignored when used as
-  /// an interface.
-  List<TypeBuilder>? ignoreFunction(List<TypeBuilder>? interfaces) {
-    if (interfaces == null) return null;
-    for (int i = 0; i < interfaces!.length; i++) {
-      ClassBuilder? classBuilder = getClass(interfaces[i]);
-      if (classBuilder != null && classBuilder.cls == hierarchy.functionClass) {
-        if (interfaces.length == 1) {
-          return null;
-        } else {
-          interfaces = interfaces.toList();
-          interfaces.removeAt(i);
-          return ignoreFunction(interfaces);
-        }
-      }
-    }
-    return interfaces;
-  }
-}
-
-class ClassHierarchyNode {
-  /// The class corresponding to this hierarchy node.
-  final ClassBuilder classBuilder;
-
-  /// All the members of this class including [classMembers] of its
-  /// superclasses. The members are sorted by [compareDeclarations].
-  final Map<Name, ClassMember> classMemberMap;
-
-  /// Similar to [classMembers] but for setters.
-  final Map<Name, ClassMember> classSetterMap;
-
-  /// All the interface members of this class including [interfaceMembers] of
-  /// its supertypes. The members are sorted by [compareDeclarations].
-  ///
-  /// In addition to the members of [classMembers] this also contains members
-  /// from interfaces.
-  ///
-  /// This may be null, in which case [classMembers] is the interface members.
-  final Map<Name, ClassMember>? interfaceMemberMap;
-
-  /// Similar to [interfaceMembers] but for setters.
-  ///
-  /// This may be null, in which case [classSetters] is the interface setters.
-  final Map<Name, ClassMember>? interfaceSetterMap;
-
-  /// All superclasses of [classBuilder] excluding itself. The classes are
-  /// sorted by depth from the root (Object) in ascending order.
-  final List<Supertype> superclasses;
-
-  /// The list of all classes implemented by [classBuilder] and its supertypes
-  /// excluding any classes from [superclasses].
-  final List<Supertype> interfaces;
-
-  /// The longest inheritance path from [classBuilder] to `Object`.
-  final int maxInheritancePath;
-
-  int get depth => superclasses.length;
-
-  final bool hasNoSuchMethod;
-
-  final ClassHierarchyNodeDataForTesting? dataForTesting;
-
-  ClassHierarchyNode(
-      this.classBuilder,
-      this.classMemberMap,
-      this.classSetterMap,
-      this.interfaceMemberMap,
-      this.interfaceSetterMap,
-      this.superclasses,
-      this.interfaces,
-      this.maxInheritancePath,
-      this.hasNoSuchMethod,
-      this.dataForTesting);
-
-  /// Returns a list of all supertypes of [classBuilder], including this node.
-  List<ClassHierarchyNode> computeAllSuperNodes(
-      ClassHierarchyBuilder hierarchy) {
-    List<ClassHierarchyNode> result = [];
-    for (int i = 0; i < superclasses.length; i++) {
-      Supertype type = superclasses[i];
-      result.add(hierarchy.getNodeFromClass(type.classNode));
-    }
-    for (int i = 0; i < interfaces.length; i++) {
-      Supertype type = interfaces[i];
-      result.add(hierarchy.getNodeFromClass(type.classNode));
-    }
-    result.add(this);
-    return result;
-  }
-
-  @override
-  String toString() {
-    StringBuffer sb = new StringBuffer();
-    sb
-      ..write(classBuilder.fullNameForErrors)
-      ..writeln(":");
-    if (maxInheritancePath != this.depth) {
-      sb
-        ..write("  Longest path to Object: ")
-        ..writeln(maxInheritancePath);
-    }
-    sb..writeln("  superclasses:");
-    int depth = 0;
-    for (Supertype superclass in superclasses) {
-      sb.write("  " * (depth + 2));
-      if (depth != 0) sb.write("-> ");
-      sb.write(typeToText(superclass.asInterfaceType));
-      sb.writeln();
-      depth++;
-    }
-    // ignore: unnecessary_null_comparison
-    if (interfaces != null) {
-      sb.write("  interfaces:");
-      bool first = true;
-      for (Supertype i in interfaces) {
-        if (!first) sb.write(",");
-        sb.write(" ");
-        sb.write(typeToText(i.asInterfaceType));
-        first = false;
-      }
-      sb.writeln();
-    }
-    printMemberMap(classMemberMap, sb, "classMembers");
-    printMemberMap(classSetterMap, sb, "classSetters");
-    if (interfaceMemberMap != null) {
-      printMemberMap(interfaceMemberMap!, sb, "interfaceMembers");
-    }
-    if (interfaceSetterMap != null) {
-      printMemberMap(interfaceSetterMap!, sb, "interfaceSetters");
-    }
-    return "$sb";
-  }
-
-  void printMembers(
-      List<ClassMember> members, StringBuffer sb, String heading) {
-    sb.write("  ");
-    sb.write(heading);
-    sb.writeln(":");
-    for (ClassMember member in members) {
-      sb
-        ..write("    ")
-        ..write(member.classBuilder.fullNameForErrors)
-        ..write(".")
-        ..write(member.fullNameForErrors)
-        ..writeln();
-    }
-  }
-
-  void printMemberMap(
-      Map<Name, ClassMember> memberMap, StringBuffer sb, String heading) {
-    List<ClassMember> members = memberMap.values.toList();
-    members.sort(compareDeclarations);
-    printMembers(members, sb, heading);
-  }
-
-  ClassMember? getInterfaceMember(Name name, bool isSetter) {
-    return isSetter
-        ? (interfaceSetterMap ?? classSetterMap)[name]
-        : (interfaceMemberMap ?? classMemberMap)[name];
-  }
-
-  ClassMember? findMember(Name name, List<ClassMember> declarations) {
-    // TODO(ahe): Consider creating a map or scope. The obvious choice would be
-    // to use scopes, but they don't handle private names correctly.
-
-    // This is a copy of `ClassHierarchy.findMemberByName`.
-    int low = 0, high = declarations.length - 1;
-    while (low <= high) {
-      int mid = low + ((high - low) >> 1);
-      ClassMember pivot = declarations[mid];
-      int comparison = ClassHierarchy.compareNames(name, pivot.name);
-      if (comparison < 0) {
-        high = mid - 1;
-      } else if (comparison > 0) {
-        low = mid + 1;
-      } else if (high != mid) {
-        // Ensure we find the first element of the given name.
-        high = mid;
-      } else {
-        return pivot;
-      }
-    }
-    return null;
-  }
-
-  ClassMember? getDispatchTarget(Name name, bool isSetter) {
-    return isSetter ? classSetterMap[name] : classMemberMap[name];
-  }
-
-  static int compareMaxInheritancePath(
-      ClassHierarchyNode a, ClassHierarchyNode b) {
-    return b.maxInheritancePath.compareTo(a.maxInheritancePath);
-  }
-}
-
-class ClassHierarchyNodeDataForTesting {
-  final List<ClassMember> abstractMembers;
-  final Map<ClassMember, Set<ClassMember>> declaredOverrides;
-  final Map<ClassMember, Set<ClassMember>> mixinApplicationOverrides;
-  final Map<ClassMember, Set<ClassMember>> inheritedImplements;
-  final Map<ClassMember, ClassMember> aliasMap = {};
-
-  ClassHierarchyNodeDataForTesting(this.abstractMembers, this.declaredOverrides,
-      this.mixinApplicationOverrides, this.inheritedImplements);
-}
-
-List<LocatedMessage> _inheritedConflictContext(ClassMember a, ClassMember b) {
-  int length = a.fullNameForErrors.length;
-  // TODO(ahe): Delete this method when it isn't used by [InterfaceResolver].
-  int compare = "${a.fileUri}".compareTo("${b.fileUri}");
-  if (compare == 0) {
-    compare = a.charOffset.compareTo(b.charOffset);
-  }
-  ClassMember first;
-  ClassMember second;
-  if (compare < 0) {
-    first = a;
-    second = b;
-  } else {
-    first = b;
-    second = a;
-  }
-  return <LocatedMessage>[
-    messageInheritedMembersConflictCause1.withLocation(
-        first.fileUri, first.charOffset, length),
-    messageInheritedMembersConflictCause2.withLocation(
-        second.fileUri, second.charOffset, length),
-  ];
-}
-
-class BuilderMixinInferrer extends MixinInferrer {
-  final ClassBuilder cls;
-
-  BuilderMixinInferrer(
-      this.cls, CoreTypes coreTypes, TypeBuilderConstraintGatherer gatherer)
-      : super(coreTypes, gatherer);
-
-  @override
-  Supertype? asInstantiationOf(Supertype type, Class superclass) {
-    List<DartType>? arguments =
-        gatherer.getTypeArgumentsAsInstanceOf(type.asInterfaceType, superclass);
-    if (arguments == null) return null;
-    return new Supertype(superclass, arguments);
-  }
-
-  @override
-  void reportProblem(Message message, Class kernelClass) {
-    int length = cls.isMixinApplication ? 1 : cls.fullNameForErrors.length;
-    cls.addProblem(message, cls.charOffset, length);
-  }
-}
-
-class TypeBuilderConstraintGatherer extends TypeConstraintGatherer
-    with StandardBounds, TypeSchemaStandardBounds {
-  @override
-  final ClassHierarchyBuilder hierarchy;
-
-  TypeBuilderConstraintGatherer(this.hierarchy,
-      Iterable<TypeParameter> typeParameters, Library currentLibrary)
-      : super.subclassing(typeParameters, currentLibrary);
-
-  @override
-  CoreTypes get coreTypes => hierarchy.coreTypes;
-
-  @override
-  void addLowerBound(
-      TypeConstraint constraint, DartType lower, Library clientLibrary) {
-    constraint.lower =
-        getStandardUpperBound(constraint.lower, lower, clientLibrary);
-  }
-
-  @override
-  void addUpperBound(
-      TypeConstraint constraint, DartType upper, Library clientLibrary) {
-    constraint.upper =
-        getStandardLowerBound(constraint.upper, upper, clientLibrary);
-  }
-
-  @override
-  Member? getInterfaceMember(Class class_, Name name, {bool setter: false}) {
-    return null;
-  }
-
-  @override
-  InterfaceType getTypeAsInstanceOf(InterfaceType type, Class superclass,
-      Library clientLibrary, CoreTypes coreTypes) {
-    return hierarchy.getTypeAsInstanceOf(type, superclass, clientLibrary);
-  }
-
-  @override
-  List<DartType>? getTypeArgumentsAsInstanceOf(
-      InterfaceType type, Class superclass) {
-    return hierarchy.getTypeArgumentsAsInstanceOf(type, superclass);
-  }
-
-  @override
-  InterfaceType futureType(DartType type, Nullability nullability) {
-    return new InterfaceType(
-        hierarchy.futureClass, nullability, <DartType>[type]);
-  }
-
-  @override
-  bool isSubtypeOf(
-      DartType subtype, DartType supertype, SubtypeCheckMode mode) {
-    return hierarchy.types.isSubtypeOf(subtype, supertype, mode);
-  }
-
-  @override
-  bool areMutualSubtypes(DartType s, DartType t, SubtypeCheckMode mode) {
-    return isSubtypeOf(s, t, mode) && isSubtypeOf(t, s, mode);
-  }
-}
-
-abstract class DelayedCheck {
-  void check(ClassHierarchyBuilder hierarchy);
-}
-
-class DelayedOverrideCheck implements DelayedCheck {
-  final SourceClassBuilder _classBuilder;
-  final ClassMember _declaredMember;
-  final Set<ClassMember> _overriddenMembers;
-
-  DelayedOverrideCheck(
-      this._classBuilder, this._declaredMember, this._overriddenMembers);
-
-  @override
-  void check(ClassHierarchyBuilder hierarchy) {
-    Member declaredMember = _declaredMember.getMember(hierarchy);
-
-    /// If [_declaredMember] is a class member that is declared in an opt-in
-    /// library but inherited to [_classBuilder] through an opt-out class then
-    /// we need to apply legacy erasure to the declared type to get the
-    /// inherited type.
-    ///
-    /// For interface members this is handled by member signatures but since
-    /// these are abstract they will never be the inherited class member.
-    ///
-    /// For instance:
-    ///
-    ///    // Opt in:
-    ///    class Super {
-    ///      int extendedMethod(int i, {required int j}) => i;
-    ///    }
-    ///    class Mixin {
-    ///      int mixedInMethod(int i, {required int j}) => i;
-    ///    }
-    ///    // Opt out:
-    ///    class Legacy extends Super with Mixin {}
-    ///    // Opt in:
-    ///    class Class extends Legacy {
-    ///      // Valid overrides since the type of `Legacy.extendedMethod` is
-    ///      // `int* Function(int*, {int* j})`.
-    ///      int? extendedMethod(int? i, {int? j}) => i;
-    ///      // Valid overrides since the type of `Legacy.mixedInMethod` is
-    ///      // `int* Function(int*, {int* j})`.
-    ///      int? mixedInMethod(int? i, {int? j}) => i;
-    ///    }
-    ///
-    bool declaredNeedsLegacyErasure =
-        needsLegacyErasure(_classBuilder.cls, declaredMember.enclosingClass!);
-    void callback(Member interfaceMember, bool isSetter) {
-      _classBuilder.checkOverride(
-          hierarchy.types, declaredMember, interfaceMember, isSetter, callback,
-          isInterfaceCheck: !_classBuilder.isMixinApplication,
-          declaredNeedsLegacyErasure: declaredNeedsLegacyErasure);
-    }
-
-    for (ClassMember overriddenMember in _overriddenMembers) {
-      callback(overriddenMember.getMember(hierarchy), _declaredMember.isSetter);
-    }
-  }
-}
-
-class DelayedGetterSetterCheck implements DelayedCheck {
-  final SourceClassBuilder classBuilder;
-  final ClassMember getter;
-  final ClassMember setter;
-
-  const DelayedGetterSetterCheck(this.classBuilder, this.getter, this.setter);
-
-  @override
-  void check(ClassHierarchyBuilder hierarchy) {
-    classBuilder.checkGetterSetter(hierarchy.types, getter.getMember(hierarchy),
-        setter.getMember(hierarchy));
-  }
-}
-
-class DelayedTypeComputation {
-  final ClassHierarchyNodeBuilder builder;
-  final ClassMember declaredMember;
-  final Set<ClassMember> overriddenMembers;
-  bool _computed = false;
-
-  DelayedTypeComputation(
-      this.builder, this.declaredMember, this.overriddenMembers)
-      : assert(declaredMember.isSourceDeclaration);
-
-  void compute(ClassHierarchyBuilder hierarchy) {
-    if (_computed) return;
-    declaredMember.inferType(hierarchy);
-    _computed = true;
-    if (declaredMember.isField) {
-      builder.inferFieldSignature(hierarchy, declaredMember, overriddenMembers);
-    } else if (declaredMember.isGetter) {
-      builder.inferGetterSignature(
-          hierarchy, declaredMember, overriddenMembers);
-    } else if (declaredMember.isSetter) {
-      builder.inferSetterSignature(
-          hierarchy, declaredMember, overriddenMembers);
-    } else {
-      builder.inferMethodSignature(
-          hierarchy, declaredMember, overriddenMembers);
-    }
-  }
-
-  @override
-  String toString() => 'DelayedTypeComputation('
-      '${builder.classBuilder.name},$declaredMember,$overriddenMembers)';
-}
-
-int compareNamedParameters(VariableDeclaration a, VariableDeclaration b) {
-  return a.name!.compareTo(b.name!);
-}
-
-void reportCantInferParameterType(
-    ClassBuilder cls,
-    FormalParameterBuilder parameter,
-    ClassHierarchyBuilder hierarchy,
-    Iterable<ClassMember> overriddenMembers) {
-  String name = parameter.name;
-  List<LocatedMessage> context = overriddenMembers
-      .map((ClassMember overriddenMember) {
-        return messageDeclaredMemberConflictsWithOverriddenMembersCause
-            .withLocation(overriddenMember.fileUri, overriddenMember.charOffset,
-                overriddenMember.fullNameForErrors.length);
-      })
-      // Call toSet to avoid duplicate context for instance of fields that are
-      // overridden both as getters and setters.
-      .toSet()
-      .toList();
-  cls.addProblem(
-      templateCantInferTypeDueToNoCombinedSignature.withArguments(name),
-      parameter.charOffset,
-      name.length,
-      wasHandled: true,
-      context: context);
-}
-
-void reportCantInferTypes(ClassBuilder cls, SourceProcedureBuilder member,
-    ClassHierarchyBuilder hierarchy, Iterable<ClassMember> overriddenMembers) {
-  String name = member.fullNameForErrors;
-  List<LocatedMessage> context = overriddenMembers
-      .map((ClassMember overriddenMember) {
-        return messageDeclaredMemberConflictsWithOverriddenMembersCause
-            .withLocation(overriddenMember.fileUri, overriddenMember.charOffset,
-                overriddenMember.fullNameForErrors.length);
-      })
-      // Call toSet to avoid duplicate context for instance of fields that are
-      // overridden both as getters and setters.
-      .toSet()
-      .toList();
-  cls.addProblem(
-      templateCantInferTypesDueToNoCombinedSignature.withArguments(name),
-      member.charOffset,
-      name.length,
-      wasHandled: true,
-      context: context);
-}
-
-void reportCantInferReturnType(ClassBuilder cls, SourceProcedureBuilder member,
-    ClassHierarchyBuilder hierarchy, Iterable<ClassMember> overriddenMembers) {
-  String name = member.fullNameForErrors;
-  List<LocatedMessage> context = overriddenMembers
-      .map((ClassMember overriddenMember) {
-        return messageDeclaredMemberConflictsWithOverriddenMembersCause
-            .withLocation(overriddenMember.fileUri, overriddenMember.charOffset,
-                overriddenMember.fullNameForErrors.length);
-      })
-      // Call toSet to avoid duplicate context for instance of fields that are
-      // overridden both as getters and setters.
-      .toSet()
-      .toList();
-  // // TODO(ahe): The following is for debugging, but could be cleaned up and
-  // // used to improve this error message in general.
-  //
-  // context = <LocatedMessage>[];
-  // ClassHierarchyNode supernode = hierarchy.getNodeFromType(cls.supertype);
-  // // TODO(ahe): Wrong template.
-  // Template<Message Function(String)> template =
-  //     templateMissingImplementationCause;
-  // if (supernode != null) {
-  //   Declaration superMember =
-  //       supernode.getInterfaceMember(new Name(name), false);
-  //   if (superMember != null) {
-  //     context.add(template
-  //         .withArguments(name)
-  //         .withLocation(
-  //             superMember.fileUri, superMember.charOffset, name.length));
-  //   }
-  //   superMember = supernode.getInterfaceMember(new Name(name), true);
-  //   if (superMember != null) {
-  //     context.add(template
-  //         .withArguments(name)
-  //         .withLocation(
-  //             superMember.fileUri, superMember.charOffset, name.length));
-  //   }
-  // }
-  // List<TypeBuilder> directInterfaces = cls.interfaces;
-  // for (int i = 0; i < directInterfaces.length; i++) {
-  //   ClassHierarchyNode supernode =
-  //       hierarchy.getNodeFromType(directInterfaces[i]);
-  //   if (supernode != null) {
-  //     Declaration superMember =
-  //         supernode.getInterfaceMember(new Name(name), false);
-  //     if (superMember != null) {
-  //       context.add(template
-  //           .withArguments(name)
-  //           .withLocation(
-  //               superMember.fileUri, superMember.charOffset, name.length));
-  //     }
-  //     superMember = supernode.getInterfaceMember(new Name(name), true);
-  //     if (superMember != null) {
-  //       context.add(template
-  //           .withArguments(name)
-  //           .withLocation(
-  //               superMember.fileUri, superMember.charOffset, name.length));
-  //     }
-  //   }
-  // }
-  cls.addProblem(
-      templateCantInferReturnTypeDueToNoCombinedSignature.withArguments(name),
-      member.charOffset,
-      name.length,
-      wasHandled: true,
-      context: context);
-}
-
-void reportCantInferFieldType(ClassBuilder cls, SourceFieldBuilder member,
-    Iterable<ClassMember> overriddenMembers) {
-  List<LocatedMessage> context = overriddenMembers
-      .map((ClassMember overriddenMember) {
-        return messageDeclaredMemberConflictsWithOverriddenMembersCause
-            .withLocation(overriddenMember.fileUri, overriddenMember.charOffset,
-                overriddenMember.fullNameForErrors.length);
-      })
-      // Call toSet to avoid duplicate context for instance of fields that are
-      // overridden both as getters and setters.
-      .toSet()
-      .toList();
-  String name = member.fullNameForErrors;
-  cls.addProblem(
-      templateCantInferTypeDueToNoCombinedSignature.withArguments(name),
-      member.charOffset,
-      name.length,
-      wasHandled: true,
-      context: context);
-}
-
-ClassBuilder? getClass(TypeBuilder type) {
-  Builder? declaration = type.declaration;
-  if (declaration is TypeAliasBuilder) {
-    TypeAliasBuilder aliasBuilder = declaration;
-    NamedTypeBuilder namedBuilder = type as NamedTypeBuilder;
-    declaration = aliasBuilder.unaliasDeclaration(namedBuilder.arguments);
-  }
-  return declaration is ClassBuilder ? declaration : null;
-}
-
-Set<ClassMember> toSet(
-    ClassBuilder classBuilder, Iterable<ClassMember> members) {
-  Set<ClassMember> result = <ClassMember>{};
-  _toSet(classBuilder, members, result);
-  return result;
-}
-
-void _toSet(ClassBuilder classBuilder, Iterable<ClassMember> members,
-    Set<ClassMember> result) {
-  for (ClassMember member in members) {
-    if (member.hasDeclarations && classBuilder == member.classBuilder) {
-      _toSet(classBuilder, member.declarations, result);
-    } else {
-      result.add(member);
-    }
-  }
-}
-
-Set<ClassMember> unfoldDeclarations(Iterable<ClassMember> members) {
-  Set<ClassMember> result = <ClassMember>{};
-  _unfoldDeclarations(members, result);
-  return result;
-}
-
-void _unfoldDeclarations(
-    Iterable<ClassMember> members, Set<ClassMember> result) {
-  for (ClassMember member in members) {
-    if (member.hasDeclarations) {
-      _unfoldDeclarations(member.declarations, result);
-    } else {
-      result.add(member);
-    }
-  }
-}
-
-abstract class SynthesizedMember extends ClassMember {
-  @override
-  final ClassBuilder classBuilder;
-
-  @override
-  final Name name;
-
-  @override
-  final bool forSetter;
-
-  @override
-  final bool isProperty;
-
-  SynthesizedMember(this.classBuilder, this.name,
-      {required this.forSetter, required this.isProperty})
-      // ignore: unnecessary_null_comparison
-      : assert(forSetter != null),
-        // ignore: unnecessary_null_comparison
-        assert(isProperty != null);
-
-  @override
-  List<ClassMember> get declarations => throw new UnimplementedError();
-
-  @override
-  void inferType(ClassHierarchyBuilder hierarchy) {}
-
-  @override
-  bool get isAssignable => throw new UnimplementedError();
-
-  @override
-  bool get isConst => throw new UnimplementedError();
-
-  @override
-  bool get isDuplicate => false;
-
-  @override
-  bool get isField => throw new UnimplementedError();
-
-  @override
-  bool get isFinal => throw new UnimplementedError();
-
-  @override
-  bool get isGetter => throw new UnimplementedError();
-
-  @override
-  bool get isInternalImplementation => false;
-
-  @override
-  bool get isSetter => forSetter;
-
-  @override
-  bool get isSourceDeclaration => false;
-
-  @override
-  bool get isStatic => false;
-
-  @override
-  bool get isSynthesized => true;
-
-  @override
-  void registerOverrideDependency(Set<ClassMember> overriddenMembers) {}
-}
-
-/// Class member for a set of interface members.
-///
-/// This is used to compute combined member signature of a set of interface
-/// members inherited into the same class, and to insert forwarding stubs,
-/// mixin stubs, and member signatures where needed.
-class SynthesizedInterfaceMember extends SynthesizedMember {
-  @override
-  final List<ClassMember> declarations;
-
-  /// The concrete member in the super class overridden by [declarations], if
-  /// any.
-  ///
-  /// This is used to as the target when creating concrete forwarding and mixin
-  /// stub. For instance:
-  ///
-  ///    class Super {
-  ///      method(int i) {}
-  ///    }
-  ///    class Interface {
-  ///      method(covariant int i) {}
-  ///    }
-  ///    class Class extends Super implements Interface {
-  ///      // Concrete forwarding stub calling [_superClassMember]:
-  ///      method(covariant int i) => super.method(i);
-  ///
-  final ClassMember? _superClassMember;
-
-  /// The canonical member of the combined member signature if it is known by
-  /// construction. The canonical member defines the type of combined member
-  /// signature.
-  ///
-  /// This is used when a declared member is part of a set of implemented
-  /// members. For instance
-  ///
-  ///     class Super {
-  ///       method(int i) {}
-  ///     }
-  ///     class Interface {
-  ///       method(covariant num i) {}
-  ///     }
-  ///     class Class implements Interface {
-  ///       // This member is updated to be a concrete forwarding stub with an
-  ///       // covariant parameter but with its declared parameter type:
-  ///       //    method(covariant int i) => super.method(i);
-  ///       method(int i);
-  ///     }
-  final ClassMember? _canonicalMember;
-
-  /// The member in [declarations] that is mixed in, if any.
-  ///
-  /// This is used to create mixin stubs. If the mixed in member is abstract,
-  /// an abstract mixin stub is created:
-  ///
-  ///    class Super {
-  ///      void method() {}
-  ///    }
-  ///    class Mixin {
-  ///      void method();
-  ///    }
-  ///    // Abstract mixin stub with `Mixin.method` as target inserted:
-  ///    //   void method();
-  ///    class Class = Super with Mixin;
-  ///
-  /// If the mixed in member is concrete, a concrete mixin member is created:
-  ///
-  ///    class Super {
-  ///      void method() {}
-  ///    }
-  ///    class Mixin {
-  ///      void method() {}
-  ///    }
-  ///    // Concrete mixin stub with `Mixin.method` as target inserted:
-  ///    //   void method() => super.method();
-  ///    class Class = Super with Mixin;
-  ///
-  /// If a forwarding stub is needed, the created stub will be a possibly
-  /// concrete forwarding stub:
-  ///
-  ///    class Super {
-  ///      void method(int i) {}
-  ///    }
-  ///    class Interface {
-  ///      void method(covariant num i) {}
-  ///    }
-  ///    class Mixin {
-  ///      void method(int i);
-  ///    }
-  ///    // Concrete forwarding stub with `Super.method` as target inserted:
-  ///    //   void method(covariant int i) => super.method(i);
-  ///    class Class = Super with Mixin implements Interface;
-  ///
-  final ClassMember? _mixedInMember;
-
-  /// If `true`, a stub should be inserted, if needed.
-  final bool _shouldModifyKernel;
-
-  Member? _member;
-  Covariance? _covariance;
-
-  SynthesizedInterfaceMember(
-      ClassBuilder classBuilder, Name name, this.declarations,
-      {ClassMember? superClassMember,
-      ClassMember? canonicalMember,
-      ClassMember? mixedInMember,
-      required bool isProperty,
-      required bool forSetter,
-      required bool shouldModifyKernel})
-      : this._superClassMember = superClassMember,
-        this._canonicalMember = canonicalMember,
-        this._mixedInMember = mixedInMember,
-        this._shouldModifyKernel = shouldModifyKernel,
-        super(classBuilder, name, isProperty: isProperty, forSetter: forSetter);
-
-  @override
-  bool get hasDeclarations => true;
-
-  void _ensureMemberAndCovariance(ClassHierarchyBuilder hierarchy) {
-    if (_member != null) {
-      return;
-    }
-    if (classBuilder.library is! SourceLibraryBuilder) {
-      if (_canonicalMember != null) {
-        _member = _canonicalMember!.getMember(hierarchy);
-        _covariance = _canonicalMember!.getCovariance(hierarchy);
-      } else {
-        _member = declarations.first.getMember(hierarchy);
-        _covariance = declarations.first.getCovariance(hierarchy);
-      }
-      return;
-    }
-    CombinedClassMemberSignature combinedMemberSignature;
-    if (_canonicalMember != null) {
-      combinedMemberSignature = new CombinedClassMemberSignature.internal(
-          hierarchy,
-          classBuilder as SourceClassBuilder,
-          declarations.indexOf(_canonicalMember!),
-          declarations,
-          forSetter: isSetter);
-    } else {
-      combinedMemberSignature = new CombinedClassMemberSignature(
-          hierarchy, classBuilder as SourceClassBuilder, declarations,
-          forSetter: isSetter);
-
-      if (combinedMemberSignature.canonicalMember == null) {
-        String name = classBuilder.fullNameForErrors;
-        int length = classBuilder.isAnonymousMixinApplication ? 1 : name.length;
-        List<LocatedMessage> context = declarations.map((ClassMember d) {
-          return messageDeclaredMemberConflictsWithOverriddenMembersCause
-              .withLocation(
-                  d.fileUri, d.charOffset, d.fullNameForErrors.length);
-        }).toList();
-
-        classBuilder.addProblem(
-            templateCombinedMemberSignatureFailed.withArguments(
-                classBuilder.fullNameForErrors,
-                declarations.first.fullNameForErrors),
-            classBuilder.charOffset,
-            length,
-            context: context);
-        // TODO(johnniwinther): Maybe we should have an invalid marker to avoid
-        // cascading errors.
-        _member = declarations.first.getMember(hierarchy);
-        _covariance = declarations.first.getCovariance(hierarchy);
-        return;
-      }
-    }
-
-    if (_shouldModifyKernel) {
-      ProcedureKind kind = ProcedureKind.Method;
-      Member canonicalMember =
-          combinedMemberSignature.canonicalMember!.getMember(hierarchy);
-      if (combinedMemberSignature.canonicalMember!.isProperty) {
-        kind = isSetter ? ProcedureKind.Setter : ProcedureKind.Getter;
-      } else if (canonicalMember is Procedure &&
-          canonicalMember.kind == ProcedureKind.Operator) {
-        kind = ProcedureKind.Operator;
-      }
-
-      Procedure? stub = new ForwardingNode(
-              combinedMemberSignature, kind, _superClassMember, _mixedInMember)
-          .finalize();
-      if (stub != null) {
-        assert(classBuilder.cls == stub.enclosingClass);
-        assert(stub != canonicalMember);
-        classBuilder.cls.addProcedure(stub);
-        SourceLibraryBuilder library =
-            classBuilder.library as SourceLibraryBuilder;
-        if (canonicalMember is Procedure) {
-          library.forwardersOrigins
-            ..add(stub)
-            ..add(canonicalMember);
-        }
-        _member = stub;
-        _covariance = combinedMemberSignature.combinedMemberSignatureCovariance;
-        assert(
-            _covariance ==
-                new Covariance.fromMember(_member!, forSetter: forSetter),
-            "Unexpected covariance for combined members signature "
-            "$_member. Found $_covariance, expected "
-            "${new Covariance.fromMember(_member!, forSetter: forSetter)}.");
-        return;
-      }
-    }
-
-    _member = combinedMemberSignature.canonicalMember!.getMember(hierarchy);
-    _covariance = combinedMemberSignature.combinedMemberSignatureCovariance;
-  }
-
-  @override
-  Member getMember(ClassHierarchyBuilder hierarchy) {
-    _ensureMemberAndCovariance(hierarchy);
-    return _member!;
-  }
-
-  @override
-  Covariance getCovariance(ClassHierarchyBuilder hierarchy) {
-    _ensureMemberAndCovariance(hierarchy);
-    return _covariance!;
-  }
-
-  @override
-  ClassMember get interfaceMember => this;
-
-  @override
-  bool isObjectMember(ClassBuilder objectClass) {
-    return false;
-  }
-
-  @override
-  bool isSameDeclaration(ClassMember other) {
-    // TODO(johnniwinther): Optimize this.
-    return false;
-  }
-
-  @override
-  int get charOffset => declarations.first.charOffset;
-
-  @override
-  Uri get fileUri => declarations.first.fileUri;
-
-  @override
-  bool get isAbstract => true;
-
-  @override
-  String get fullNameForErrors =>
-      declarations.map((ClassMember m) => m.fullName).join("%");
-
-  @override
-  String get fullName {
-    String suffix = isSetter ? "=" : "";
-    return "${fullNameForErrors}$suffix";
-  }
-
-  @override
-  String toString() => 'SynthesizedInterfaceMember($classBuilder,$name,'
-      '$declarations,forSetter=$forSetter)';
-}
-
-/// Class member for an inherited concrete member that implements an interface
-/// member.
-///
-/// This is used to ensure that both the inherited concrete member and the
-/// interface member is taken into account when computing the resulting [Member]
-/// node.
-///
-/// This is needed because an interface member, though initially abstract, can
-/// result in a concrete stub that overrides the concrete member. For instance
-///
-///    class Super {
-///      method(int i) {}
-///    }
-///    class Interface {
-///      method(covariant int i) {}
-///    }
-///    class Class extends Super implements Interface {
-///      // A concrete forwarding stub is inserted:
-///      method(covariant int i) => super.method(i);
-///    }
-///    class Sub extends Class implements Interface {
-///      // No forwarding stub should be inserted since `Class.method` is
-///      // adequate.
-///    }
-///
-///
-///  Here the create stub `Class.method` overrides `Super.method` and should
-///  be used to determine whether to insert a forwarding stub in subclasses.
-class InheritedClassMemberImplementsInterface extends SynthesizedMember {
-  final ClassMember inheritedClassMember;
-  final ClassMember implementedInterfaceMember;
-
-  Member? _member;
-  Covariance? _covariance;
-
-  InheritedClassMemberImplementsInterface(ClassBuilder classBuilder, Name name,
-      {required this.inheritedClassMember,
-      required this.implementedInterfaceMember,
-      required bool isProperty,
-      required bool forSetter})
-      // ignore: unnecessary_null_comparison
-      : assert(inheritedClassMember != null),
-        // ignore: unnecessary_null_comparison
-        assert(implementedInterfaceMember != null),
-        super(classBuilder, name, isProperty: isProperty, forSetter: forSetter);
-
-  void _ensureMemberAndCovariance(ClassHierarchyBuilder hierarchy) {
-    if (_member == null) {
-      Member classMember = inheritedClassMember.getMember(hierarchy);
-      Member interfaceMember = implementedInterfaceMember.getMember(hierarchy);
-      if (!interfaceMember.isAbstract &&
-          interfaceMember.enclosingClass == classBuilder.cls) {
-        /// The interface member resulted in a concrete stub being inserted.
-        /// For instance for `method1` but _not_ for `method2` here:
-        ///
-        ///    class Super {
-        ///      method1(int i) {}
-        ///      method2(covariant int i) {}
-        ///    }
-        ///    class Interface {
-        ///      method1(covariant int i) {}
-        ///      method2(int i) {}
-        ///    }
-        ///    class Class extends Super implements Interface {
-        ///      // A concrete forwarding stub is inserted for `method1` since
-        ///      // the parameter on `Super.method1` is _not_ marked as
-        ///      // covariant:
-        ///      method1(covariant int i) => super.method(i);
-        ///      // No concrete forwarding stub is inserted for `method2` since
-        ///      // the parameter on `Super.method2` is already marked as
-        ///      // covariant.
-        ///    }
-        ///
-        /// The inserted stub should be used as the resulting member.
-        _member = interfaceMember;
-        _covariance = implementedInterfaceMember.getCovariance(hierarchy);
-      } else {
-        /// The interface member did not result in an inserted stub or the
-        /// inserted stub was abstract. For instance:
-        ///
-        ///    // Opt-in:
-        ///    class Super {
-        ///      method(int? i) {}
-        ///    }
-        ///    // Opt-out:
-        ///    class Class extends Super {
-        ///      // An abstract member signature stub is inserted:
-        ///      method(int* i);
-        ///    }
-        ///
-        /// The inserted stub should _not_ be used as the resulting member
-        /// since it is abstract and therefore not a class member.
-        _member = classMember;
-        _covariance = inheritedClassMember.getCovariance(hierarchy);
-      }
-    }
-  }
-
-  @override
-  Member getMember(ClassHierarchyBuilder hierarchy) {
-    _ensureMemberAndCovariance(hierarchy);
-    return _member!;
-  }
-
-  @override
-  Covariance getCovariance(ClassHierarchyBuilder hierarchy) {
-    _ensureMemberAndCovariance(hierarchy);
-    return _covariance!;
-  }
-
-  @override
-  ClassMember get interfaceMember => implementedInterfaceMember;
-
-  @override
-  bool isObjectMember(ClassBuilder objectClass) {
-    return inheritedClassMember.isObjectMember(objectClass);
-  }
-
-  @override
-  bool isSameDeclaration(ClassMember other) {
-    // TODO(johnniwinther): Optimize this.
-    return false;
-  }
-
-  @override
-  int get charOffset => inheritedClassMember.charOffset;
-
-  @override
-  Uri get fileUri => inheritedClassMember.fileUri;
-
-  @override
-  bool get hasDeclarations => false;
-
-  @override
-  bool get isAbstract => false;
-
-  @override
-  String get fullNameForErrors => inheritedClassMember.fullNameForErrors;
-
-  @override
-  String get fullName => inheritedClassMember.fullName;
-
-  @override
-  String toString() =>
-      'InheritedClassMemberImplementsInterface($classBuilder,$name,'
-      'inheritedClassMember=$inheritedClassMember,'
-      'implementedInterfaceMember=$implementedInterfaceMember,'
-      'forSetter=$forSetter)';
-}
diff --git a/pkg/front_end/lib/src/fasta/kernel/combined_member_signature.dart b/pkg/front_end/lib/src/fasta/kernel/combined_member_signature.dart
index abff877..ae2efed 100644
--- a/pkg/front_end/lib/src/fasta/kernel/combined_member_signature.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/combined_member_signature.dart
@@ -20,7 +20,9 @@
 
 import '../source/source_class_builder.dart';
 
-import 'class_hierarchy_builder.dart';
+import 'hierarchy/class_member.dart';
+import 'hierarchy/hierarchy_builder.dart';
+import 'hierarchy/members_builder.dart';
 import 'member_covariance.dart';
 
 /// Class used for computing and inspecting the combined member signature for
@@ -736,9 +738,11 @@
 /// a set of overridden/inherited [ClassMember]s.
 class CombinedClassMemberSignature
     extends CombinedMemberSignatureBase<ClassMember> {
-  /// The class hierarchy builder used for building this class.
+  /// The class members builder used for building this class.
+  final ClassMembersBuilder membersBuilder;
+
   @override
-  final ClassHierarchyBuilder hierarchy;
+  ClassHierarchyBuilder get hierarchy => membersBuilder.hierarchyBuilder;
 
   /// The list of the members inherited into or overridden in [classBuilder].
   @override
@@ -746,7 +750,7 @@
 
   /// Creates a [CombinedClassMemberSignature] whose canonical member is already
   /// defined.
-  CombinedClassMemberSignature.internal(this.hierarchy,
+  CombinedClassMemberSignature.internal(this.membersBuilder,
       SourceClassBuilder classBuilder, int canonicalMemberIndex, this.members,
       {required bool forSetter})
       : super.internal(classBuilder, canonicalMemberIndex, forSetter);
@@ -758,7 +762,7 @@
   /// compute the most specific member type. Otherwise covariance of the getter
   /// types or function types is used.
   CombinedClassMemberSignature(
-      this.hierarchy, SourceClassBuilder classBuilder, this.members,
+      this.membersBuilder, SourceClassBuilder classBuilder, this.members,
       {required bool forSetter})
       : super(classBuilder, forSetter: forSetter);
 
@@ -771,7 +775,7 @@
   @override
   Member _getMember(int index) {
     ClassMember candidate = members[index];
-    Member target = candidate.getMember(hierarchy);
+    Member target = candidate.getMember(membersBuilder);
     // ignore: unnecessary_null_comparison
     assert(target != null,
         "No member computed for ${candidate} (${candidate.runtimeType})");
@@ -781,7 +785,7 @@
   @override
   Covariance _getMemberCovariance(int index) {
     ClassMember candidate = members[index];
-    Covariance covariance = candidate.getCovariance(hierarchy);
+    Covariance covariance = candidate.getCovariance(membersBuilder);
     // ignore: unnecessary_null_comparison
     assert(covariance != null,
         "No covariance computed for ${candidate} (${candidate.runtimeType})");
diff --git a/pkg/front_end/lib/src/fasta/kernel/constant_evaluator.dart b/pkg/front_end/lib/src/fasta/kernel/constant_evaluator.dart
index bc2af8b..cf785bd 100644
--- a/pkg/front_end/lib/src/fasta/kernel/constant_evaluator.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/constant_evaluator.dart
@@ -2464,9 +2464,8 @@
             functionEnvironment: receiver.environment);
       } else if (receiver is InstanceConstant) {
         final Class instanceClass = receiver.classNode;
-        assert(typeEnvironment.hierarchy is ClassHierarchy);
-        final Member member = (typeEnvironment.hierarchy as ClassHierarchy)
-            .getDispatchTarget(instanceClass, name)!;
+        final Member member =
+            typeEnvironment.hierarchy.getDispatchTarget(instanceClass, name)!;
         final FunctionNode? function = member.function;
 
         // TODO(kallentu): Implement [Object] class methods which have backend
diff --git a/pkg/front_end/lib/src/fasta/kernel/expression_generator.dart b/pkg/front_end/lib/src/fasta/kernel/expression_generator.dart
index ff0fb53..ce46969 100644
--- a/pkg/front_end/lib/src/fasta/kernel/expression_generator.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/expression_generator.dart
@@ -4573,8 +4573,13 @@
         _helper.lookupConstructor(name, isSuper: isSuper);
     LocatedMessage? message;
     if (constructor != null) {
-      message = _helper.checkArgumentsForFunction(
-          constructor.function, arguments, offset, <TypeParameter>[]);
+      // The check of the arguments is done later for super initializers if the
+      // 'super-parameters' language feature is enabled. In that case the
+      // additional parameters can be added at a later stage.
+      if (!(isSuper && _helper.libraryBuilder.enableSuperParametersInLibrary)) {
+        message = _helper.checkArgumentsForFunction(
+            constructor.function, arguments, offset, <TypeParameter>[]);
+      }
     } else {
       String fullName =
           _helper.constructorNameForDiagnostics(name.text, isSuper: isSuper);
diff --git a/pkg/front_end/lib/src/fasta/kernel/forwarding_node.dart b/pkg/front_end/lib/src/fasta/kernel/forwarding_node.dart
index f05f378..b5b8b97 100644
--- a/pkg/front_end/lib/src/fasta/kernel/forwarding_node.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/forwarding_node.dart
@@ -12,7 +12,7 @@
 
 import "../problems.dart" show unhandled;
 
-import 'class_hierarchy_builder.dart';
+import 'hierarchy/class_member.dart';
 import 'combined_member_signature.dart';
 
 class ForwardingNode {
@@ -49,7 +49,7 @@
     SourceClassBuilder classBuilder = _combinedMemberSignature.classBuilder;
     ClassMember canonicalMember = _combinedMemberSignature.canonicalMember!;
     Member interfaceMember =
-        canonicalMember.getMember(_combinedMemberSignature.hierarchy);
+        canonicalMember.getMember(_combinedMemberSignature.membersBuilder);
 
     bool needMixinStub =
         classBuilder.isMixinApplication && _mixedInMember != null;
@@ -83,7 +83,8 @@
             needsTypeOrCovarianceUpdate) ||
         needMixinStub;
     bool needsSuperImpl = _superClassMember != null &&
-        _superClassMember!.getCovariance(_combinedMemberSignature.hierarchy) !=
+        _superClassMember!
+                .getCovariance(_combinedMemberSignature.membersBuilder) !=
             _combinedMemberSignature.combinedMemberSignatureCovariance;
     if (stubNeeded) {
       Procedure stub = _combinedMemberSignature.createMemberFromSignature(
@@ -114,8 +115,8 @@
           }
         } else {
           stubKind = ProcedureStubKind.AbstractMixinStub;
-          finalTarget =
-              _mixedInMember!.getMember(_combinedMemberSignature.hierarchy);
+          finalTarget = _mixedInMember!
+              .getMember(_combinedMemberSignature.membersBuilder);
         }
 
         stub.stubKind = stubKind;
@@ -159,7 +160,7 @@
     }
     Procedure procedure = function.parent as Procedure;
     Member superTarget =
-        _superClassMember!.getMember(_combinedMemberSignature.hierarchy);
+        _superClassMember!.getMember(_combinedMemberSignature.membersBuilder);
     if (superTarget is Procedure && superTarget.isForwardingStub) {
       Procedure superProcedure = superTarget;
       superTarget = superProcedure.concreteForwardingStubTarget!;
diff --git a/pkg/front_end/lib/src/fasta/kernel/hierarchy/class_member.dart b/pkg/front_end/lib/src/fasta/kernel/hierarchy/class_member.dart
new file mode 100644
index 0000000..f45ba32
--- /dev/null
+++ b/pkg/front_end/lib/src/fasta/kernel/hierarchy/class_member.dart
@@ -0,0 +1,609 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library fasta.class_hierarchy_builder;
+
+import 'package:kernel/ast.dart';
+
+import '../../builder/class_builder.dart';
+import '../../messages.dart'
+    show
+        LocatedMessage,
+        messageDeclaredMemberConflictsWithOverriddenMembersCause,
+        templateCombinedMemberSignatureFailed;
+import '../../source/source_class_builder.dart';
+import '../../source/source_library_builder.dart' show SourceLibraryBuilder;
+import '../combined_member_signature.dart';
+import '../forwarding_node.dart' show ForwardingNode;
+import '../member_covariance.dart';
+import 'members_builder.dart';
+
+abstract class ClassMember {
+  Name get name;
+  bool get isStatic;
+  bool get isField;
+  bool get isAssignable;
+  bool get isSetter;
+  bool get isGetter;
+  bool get isFinal;
+  bool get isConst;
+  bool get forSetter;
+
+  /// Returns `true` if this member corresponds to a declaration in the source
+  /// code.
+  bool get isSourceDeclaration;
+
+  /// Returns `true` if this member is a field, getter or setter.
+  bool get isProperty;
+
+  /// Computes the [Member] node resulting from this class member.
+  Member getMember(ClassMembersBuilder membersBuilder);
+
+  /// Returns the member [Covariance] for this class member.
+  Covariance getCovariance(ClassMembersBuilder membersBuilder);
+
+  bool get isDuplicate;
+  String get fullName;
+  String get fullNameForErrors;
+  ClassBuilder get classBuilder;
+
+  /// Returns `true` if this class member is declared in Object from dart:core.
+  bool isObjectMember(ClassBuilder objectClass);
+  Uri get fileUri;
+  int get charOffset;
+
+  /// Returns `true` if this class member is an interface member.
+  bool get isAbstract;
+
+  /// Returns `true` if this member doesn't corresponds to a declaration in the
+  /// source code.
+  bool get isSynthesized;
+
+  // If `true` this member is not part of the interface but only part of the
+  // class members.
+  //
+  // This is `true` for instance for synthesized fields added for the late
+  // lowering.
+  bool get isInternalImplementation;
+
+  /// Returns `true` if this member is composed from a list of class members
+  /// accessible through [declarations].
+  bool get hasDeclarations;
+
+  /// If [hasDeclaration] is `true`, this returns the list of class members
+  /// from which this class member is composed.
+  ///
+  /// This is used in [unfoldDeclarations] to retrieve all underlying member
+  /// source declarations, and in [toSet] to retrieve all members used for
+  /// this class member wrt. certain level of the hierarchy.
+  /// TODO(johnniwinther): Can the use of [toSet] be replaced with a direct
+  /// use of [declarations]?
+  List<ClassMember> get declarations;
+
+  /// The interface member corresponding to this member.
+  ///
+  /// If this member is declared on the source, the interface member is
+  /// the member itself. For instance
+  ///
+  ///     abstract class Class {
+  ///        void concreteMethod() {}
+  ///        void abstractMethod();
+  ///     }
+  ///
+  /// the interface members for `concreteMethod` and `abstractMethod` are the
+  /// members themselves.
+  ///
+  /// If this member is a synthesized interface member, the
+  /// interface member is the member itself. For instance
+  ///
+  ///     abstract class Interface1 {
+  ///        void method() {}
+  ///     }
+  ///     abstract class Interface2 {
+  ///        void method() {}
+  ///     }
+  ///     abstract class Class implements Interface1, Interface2 {}
+  ///
+  /// the interface member for `method` in `Class` is the synthesized interface
+  /// member created for the implemented members `Interface1.method` and
+  /// `Interface2.method`.
+  ///
+  /// If this member is a concrete member that implements an interface member,
+  /// the interface member is the implemented interface member. For instance
+  ///
+  ///     class Super {
+  ///        void method() {}
+  ///     }
+  ///     class Interface {
+  ///        void method() {}
+  ///     }
+  ///     class Class extends Super implements Interface {}
+  ///
+  /// the interface member for `Super.method` implementing `method` in `Class`
+  /// is the synthesized interface member created for the implemented members
+  /// `Super.method` and `Interface.method`.
+  ClassMember get interfaceMember;
+
+  void inferType(ClassMembersBuilder membersBuilder);
+  void registerOverrideDependency(Set<ClassMember> overriddenMembers);
+
+  /// Returns `true` if this has the same underlying declaration as [other].
+  ///
+  /// This is used for avoiding unnecessary checks and can this trivially
+  /// return `false`.
+  bool isSameDeclaration(ClassMember other);
+}
+
+abstract class SynthesizedMember extends ClassMember {
+  @override
+  final ClassBuilder classBuilder;
+
+  @override
+  final Name name;
+
+  @override
+  final bool forSetter;
+
+  @override
+  final bool isProperty;
+
+  SynthesizedMember(this.classBuilder, this.name,
+      {required this.forSetter, required this.isProperty})
+      // ignore: unnecessary_null_comparison
+      : assert(forSetter != null),
+        // ignore: unnecessary_null_comparison
+        assert(isProperty != null);
+
+  @override
+  List<ClassMember> get declarations => throw new UnimplementedError();
+
+  @override
+  void inferType(ClassMembersBuilder membersBuilder) {}
+
+  @override
+  bool get isAssignable => throw new UnimplementedError();
+
+  @override
+  bool get isConst => throw new UnimplementedError();
+
+  @override
+  bool get isDuplicate => false;
+
+  @override
+  bool get isField => throw new UnimplementedError();
+
+  @override
+  bool get isFinal => throw new UnimplementedError();
+
+  @override
+  bool get isGetter => throw new UnimplementedError();
+
+  @override
+  bool get isInternalImplementation => false;
+
+  @override
+  bool get isSetter => forSetter;
+
+  @override
+  bool get isSourceDeclaration => false;
+
+  @override
+  bool get isStatic => false;
+
+  @override
+  bool get isSynthesized => true;
+
+  @override
+  void registerOverrideDependency(Set<ClassMember> overriddenMembers) {}
+}
+
+/// Class member for a set of interface members.
+///
+/// This is used to compute combined member signature of a set of interface
+/// members inherited into the same class, and to insert forwarding stubs,
+/// mixin stubs, and member signatures where needed.
+class SynthesizedInterfaceMember extends SynthesizedMember {
+  @override
+  final List<ClassMember> declarations;
+
+  /// The concrete member in the super class overridden by [declarations], if
+  /// any.
+  ///
+  /// This is used to as the target when creating concrete forwarding and mixin
+  /// stub. For instance:
+  ///
+  ///    class Super {
+  ///      method(int i) {}
+  ///    }
+  ///    class Interface {
+  ///      method(covariant int i) {}
+  ///    }
+  ///    class Class extends Super implements Interface {
+  ///      // Concrete forwarding stub calling [_superClassMember]:
+  ///      method(covariant int i) => super.method(i);
+  ///
+  final ClassMember? _superClassMember;
+
+  /// The canonical member of the combined member signature if it is known by
+  /// construction. The canonical member defines the type of combined member
+  /// signature.
+  ///
+  /// This is used when a declared member is part of a set of implemented
+  /// members. For instance
+  ///
+  ///     class Super {
+  ///       method(int i) {}
+  ///     }
+  ///     class Interface {
+  ///       method(covariant num i) {}
+  ///     }
+  ///     class Class implements Interface {
+  ///       // This member is updated to be a concrete forwarding stub with an
+  ///       // covariant parameter but with its declared parameter type:
+  ///       //    method(covariant int i) => super.method(i);
+  ///       method(int i);
+  ///     }
+  final ClassMember? _canonicalMember;
+
+  /// The member in [declarations] that is mixed in, if any.
+  ///
+  /// This is used to create mixin stubs. If the mixed in member is abstract,
+  /// an abstract mixin stub is created:
+  ///
+  ///    class Super {
+  ///      void method() {}
+  ///    }
+  ///    class Mixin {
+  ///      void method();
+  ///    }
+  ///    // Abstract mixin stub with `Mixin.method` as target inserted:
+  ///    //   void method();
+  ///    class Class = Super with Mixin;
+  ///
+  /// If the mixed in member is concrete, a concrete mixin member is created:
+  ///
+  ///    class Super {
+  ///      void method() {}
+  ///    }
+  ///    class Mixin {
+  ///      void method() {}
+  ///    }
+  ///    // Concrete mixin stub with `Mixin.method` as target inserted:
+  ///    //   void method() => super.method();
+  ///    class Class = Super with Mixin;
+  ///
+  /// If a forwarding stub is needed, the created stub will be a possibly
+  /// concrete forwarding stub:
+  ///
+  ///    class Super {
+  ///      void method(int i) {}
+  ///    }
+  ///    class Interface {
+  ///      void method(covariant num i) {}
+  ///    }
+  ///    class Mixin {
+  ///      void method(int i);
+  ///    }
+  ///    // Concrete forwarding stub with `Super.method` as target inserted:
+  ///    //   void method(covariant int i) => super.method(i);
+  ///    class Class = Super with Mixin implements Interface;
+  ///
+  final ClassMember? _mixedInMember;
+
+  /// If `true`, a stub should be inserted, if needed.
+  final bool _shouldModifyKernel;
+
+  Member? _member;
+  Covariance? _covariance;
+
+  SynthesizedInterfaceMember(
+      ClassBuilder classBuilder, Name name, this.declarations,
+      {ClassMember? superClassMember,
+      ClassMember? canonicalMember,
+      ClassMember? mixedInMember,
+      required bool isProperty,
+      required bool forSetter,
+      required bool shouldModifyKernel})
+      : this._superClassMember = superClassMember,
+        this._canonicalMember = canonicalMember,
+        this._mixedInMember = mixedInMember,
+        this._shouldModifyKernel = shouldModifyKernel,
+        super(classBuilder, name, isProperty: isProperty, forSetter: forSetter);
+
+  @override
+  bool get hasDeclarations => true;
+
+  void _ensureMemberAndCovariance(ClassMembersBuilder membersBuilder) {
+    if (_member != null) {
+      return;
+    }
+    if (classBuilder.library is! SourceLibraryBuilder) {
+      if (_canonicalMember != null) {
+        _member = _canonicalMember!.getMember(membersBuilder);
+        _covariance = _canonicalMember!.getCovariance(membersBuilder);
+      } else {
+        _member = declarations.first.getMember(membersBuilder);
+        _covariance = declarations.first.getCovariance(membersBuilder);
+      }
+      return;
+    }
+    CombinedClassMemberSignature combinedMemberSignature;
+    if (_canonicalMember != null) {
+      combinedMemberSignature = new CombinedClassMemberSignature.internal(
+          membersBuilder,
+          classBuilder as SourceClassBuilder,
+          declarations.indexOf(_canonicalMember!),
+          declarations,
+          forSetter: isSetter);
+    } else {
+      combinedMemberSignature = new CombinedClassMemberSignature(
+          membersBuilder, classBuilder as SourceClassBuilder, declarations,
+          forSetter: isSetter);
+
+      if (combinedMemberSignature.canonicalMember == null) {
+        String name = classBuilder.fullNameForErrors;
+        int length = classBuilder.isAnonymousMixinApplication ? 1 : name.length;
+        List<LocatedMessage> context = declarations.map((ClassMember d) {
+          return messageDeclaredMemberConflictsWithOverriddenMembersCause
+              .withLocation(
+                  d.fileUri, d.charOffset, d.fullNameForErrors.length);
+        }).toList();
+
+        classBuilder.addProblem(
+            templateCombinedMemberSignatureFailed.withArguments(
+                classBuilder.fullNameForErrors,
+                declarations.first.fullNameForErrors),
+            classBuilder.charOffset,
+            length,
+            context: context);
+        // TODO(johnniwinther): Maybe we should have an invalid marker to avoid
+        // cascading errors.
+        _member = declarations.first.getMember(membersBuilder);
+        _covariance = declarations.first.getCovariance(membersBuilder);
+        return;
+      }
+    }
+
+    if (_shouldModifyKernel) {
+      ProcedureKind kind = ProcedureKind.Method;
+      Member canonicalMember =
+          combinedMemberSignature.canonicalMember!.getMember(membersBuilder);
+      if (combinedMemberSignature.canonicalMember!.isProperty) {
+        kind = isSetter ? ProcedureKind.Setter : ProcedureKind.Getter;
+      } else if (canonicalMember is Procedure &&
+          canonicalMember.kind == ProcedureKind.Operator) {
+        kind = ProcedureKind.Operator;
+      }
+
+      Procedure? stub = new ForwardingNode(
+              combinedMemberSignature, kind, _superClassMember, _mixedInMember)
+          .finalize();
+      if (stub != null) {
+        assert(classBuilder.cls == stub.enclosingClass);
+        assert(stub != canonicalMember);
+        classBuilder.cls.addProcedure(stub);
+        SourceLibraryBuilder library =
+            classBuilder.library as SourceLibraryBuilder;
+        if (canonicalMember is Procedure) {
+          library.forwardersOrigins
+            ..add(stub)
+            ..add(canonicalMember);
+        }
+        _member = stub;
+        _covariance = combinedMemberSignature.combinedMemberSignatureCovariance;
+        assert(
+            _covariance ==
+                new Covariance.fromMember(_member!, forSetter: forSetter),
+            "Unexpected covariance for combined members signature "
+            "$_member. Found $_covariance, expected "
+            "${new Covariance.fromMember(_member!, forSetter: forSetter)}.");
+        return;
+      }
+    }
+
+    _member =
+        combinedMemberSignature.canonicalMember!.getMember(membersBuilder);
+    _covariance = combinedMemberSignature.combinedMemberSignatureCovariance;
+  }
+
+  @override
+  Member getMember(ClassMembersBuilder membersBuilder) {
+    _ensureMemberAndCovariance(membersBuilder);
+    return _member!;
+  }
+
+  @override
+  Covariance getCovariance(ClassMembersBuilder membersBuilder) {
+    _ensureMemberAndCovariance(membersBuilder);
+    return _covariance!;
+  }
+
+  @override
+  ClassMember get interfaceMember => this;
+
+  @override
+  bool isObjectMember(ClassBuilder objectClass) {
+    return false;
+  }
+
+  @override
+  bool isSameDeclaration(ClassMember other) {
+    // TODO(johnniwinther): Optimize this.
+    return false;
+  }
+
+  @override
+  int get charOffset => declarations.first.charOffset;
+
+  @override
+  Uri get fileUri => declarations.first.fileUri;
+
+  @override
+  bool get isAbstract => true;
+
+  @override
+  String get fullNameForErrors =>
+      declarations.map((ClassMember m) => m.fullName).join("%");
+
+  @override
+  String get fullName {
+    String suffix = isSetter ? "=" : "";
+    return "${fullNameForErrors}$suffix";
+  }
+
+  @override
+  String toString() => 'SynthesizedInterfaceMember($classBuilder,$name,'
+      '$declarations,forSetter=$forSetter)';
+}
+
+/// Class member for an inherited concrete member that implements an interface
+/// member.
+///
+/// This is used to ensure that both the inherited concrete member and the
+/// interface member is taken into account when computing the resulting [Member]
+/// node.
+///
+/// This is needed because an interface member, though initially abstract, can
+/// result in a concrete stub that overrides the concrete member. For instance
+///
+///    class Super {
+///      method(int i) {}
+///    }
+///    class Interface {
+///      method(covariant int i) {}
+///    }
+///    class Class extends Super implements Interface {
+///      // A concrete forwarding stub is inserted:
+///      method(covariant int i) => super.method(i);
+///    }
+///    class Sub extends Class implements Interface {
+///      // No forwarding stub should be inserted since `Class.method` is
+///      // adequate.
+///    }
+///
+///
+///  Here the create stub `Class.method` overrides `Super.method` and should
+///  be used to determine whether to insert a forwarding stub in subclasses.
+class InheritedClassMemberImplementsInterface extends SynthesizedMember {
+  final ClassMember inheritedClassMember;
+  final ClassMember implementedInterfaceMember;
+
+  Member? _member;
+  Covariance? _covariance;
+
+  InheritedClassMemberImplementsInterface(ClassBuilder classBuilder, Name name,
+      {required this.inheritedClassMember,
+      required this.implementedInterfaceMember,
+      required bool isProperty,
+      required bool forSetter})
+      // ignore: unnecessary_null_comparison
+      : assert(inheritedClassMember != null),
+        // ignore: unnecessary_null_comparison
+        assert(implementedInterfaceMember != null),
+        super(classBuilder, name, isProperty: isProperty, forSetter: forSetter);
+
+  void _ensureMemberAndCovariance(ClassMembersBuilder membersBuilder) {
+    if (_member == null) {
+      Member classMember = inheritedClassMember.getMember(membersBuilder);
+      Member interfaceMember =
+          implementedInterfaceMember.getMember(membersBuilder);
+      if (!interfaceMember.isAbstract &&
+          interfaceMember.enclosingClass == classBuilder.cls) {
+        /// The interface member resulted in a concrete stub being inserted.
+        /// For instance for `method1` but _not_ for `method2` here:
+        ///
+        ///    class Super {
+        ///      method1(int i) {}
+        ///      method2(covariant int i) {}
+        ///    }
+        ///    class Interface {
+        ///      method1(covariant int i) {}
+        ///      method2(int i) {}
+        ///    }
+        ///    class Class extends Super implements Interface {
+        ///      // A concrete forwarding stub is inserted for `method1` since
+        ///      // the parameter on `Super.method1` is _not_ marked as
+        ///      // covariant:
+        ///      method1(covariant int i) => super.method(i);
+        ///      // No concrete forwarding stub is inserted for `method2` since
+        ///      // the parameter on `Super.method2` is already marked as
+        ///      // covariant.
+        ///    }
+        ///
+        /// The inserted stub should be used as the resulting member.
+        _member = interfaceMember;
+        _covariance = implementedInterfaceMember.getCovariance(membersBuilder);
+      } else {
+        /// The interface member did not result in an inserted stub or the
+        /// inserted stub was abstract. For instance:
+        ///
+        ///    // Opt-in:
+        ///    class Super {
+        ///      method(int? i) {}
+        ///    }
+        ///    // Opt-out:
+        ///    class Class extends Super {
+        ///      // An abstract member signature stub is inserted:
+        ///      method(int* i);
+        ///    }
+        ///
+        /// The inserted stub should _not_ be used as the resulting member
+        /// since it is abstract and therefore not a class member.
+        _member = classMember;
+        _covariance = inheritedClassMember.getCovariance(membersBuilder);
+      }
+    }
+  }
+
+  @override
+  Member getMember(ClassMembersBuilder membersBuilder) {
+    _ensureMemberAndCovariance(membersBuilder);
+    return _member!;
+  }
+
+  @override
+  Covariance getCovariance(ClassMembersBuilder membersBuilder) {
+    _ensureMemberAndCovariance(membersBuilder);
+    return _covariance!;
+  }
+
+  @override
+  ClassMember get interfaceMember => implementedInterfaceMember;
+
+  @override
+  bool isObjectMember(ClassBuilder objectClass) {
+    return inheritedClassMember.isObjectMember(objectClass);
+  }
+
+  @override
+  bool isSameDeclaration(ClassMember other) {
+    // TODO(johnniwinther): Optimize this.
+    return false;
+  }
+
+  @override
+  int get charOffset => inheritedClassMember.charOffset;
+
+  @override
+  Uri get fileUri => inheritedClassMember.fileUri;
+
+  @override
+  bool get hasDeclarations => false;
+
+  @override
+  bool get isAbstract => false;
+
+  @override
+  String get fullNameForErrors => inheritedClassMember.fullNameForErrors;
+
+  @override
+  String get fullName => inheritedClassMember.fullName;
+
+  @override
+  String toString() =>
+      'InheritedClassMemberImplementsInterface($classBuilder,$name,'
+      'inheritedClassMember=$inheritedClassMember,'
+      'implementedInterfaceMember=$implementedInterfaceMember,'
+      'forSetter=$forSetter)';
+}
diff --git a/pkg/front_end/lib/src/fasta/kernel/hierarchy/delayed.dart b/pkg/front_end/lib/src/fasta/kernel/hierarchy/delayed.dart
new file mode 100644
index 0000000..61cd149
--- /dev/null
+++ b/pkg/front_end/lib/src/fasta/kernel/hierarchy/delayed.dart
@@ -0,0 +1,122 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library fasta.class_hierarchy_builder;
+
+import 'package:kernel/ast.dart';
+import 'package:kernel/src/legacy_erasure.dart';
+
+import '../../source/source_class_builder.dart';
+import 'class_member.dart';
+import 'members_builder.dart';
+import 'members_node.dart';
+
+abstract class DelayedCheck {
+  void check(ClassMembersBuilder membersBuilder);
+}
+
+class DelayedOverrideCheck implements DelayedCheck {
+  final SourceClassBuilder _classBuilder;
+  final ClassMember _declaredMember;
+  final Set<ClassMember> _overriddenMembers;
+
+  DelayedOverrideCheck(
+      this._classBuilder, this._declaredMember, this._overriddenMembers);
+
+  @override
+  void check(ClassMembersBuilder membersBuilder) {
+    Member declaredMember = _declaredMember.getMember(membersBuilder);
+
+    /// If [_declaredMember] is a class member that is declared in an opt-in
+    /// library but inherited to [_classBuilder] through an opt-out class then
+    /// we need to apply legacy erasure to the declared type to get the
+    /// inherited type.
+    ///
+    /// For interface members this is handled by member signatures but since
+    /// these are abstract they will never be the inherited class member.
+    ///
+    /// For instance:
+    ///
+    ///    // Opt in:
+    ///    class Super {
+    ///      int extendedMethod(int i, {required int j}) => i;
+    ///    }
+    ///    class Mixin {
+    ///      int mixedInMethod(int i, {required int j}) => i;
+    ///    }
+    ///    // Opt out:
+    ///    class Legacy extends Super with Mixin {}
+    ///    // Opt in:
+    ///    class Class extends Legacy {
+    ///      // Valid overrides since the type of `Legacy.extendedMethod` is
+    ///      // `int* Function(int*, {int* j})`.
+    ///      int? extendedMethod(int? i, {int? j}) => i;
+    ///      // Valid overrides since the type of `Legacy.mixedInMethod` is
+    ///      // `int* Function(int*, {int* j})`.
+    ///      int? mixedInMethod(int? i, {int? j}) => i;
+    ///    }
+    ///
+    bool declaredNeedsLegacyErasure =
+        needsLegacyErasure(_classBuilder.cls, declaredMember.enclosingClass!);
+    void callback(Member interfaceMember, bool isSetter) {
+      _classBuilder.checkOverride(membersBuilder.hierarchyBuilder.types,
+          membersBuilder, declaredMember, interfaceMember, isSetter, callback,
+          isInterfaceCheck: !_classBuilder.isMixinApplication,
+          declaredNeedsLegacyErasure: declaredNeedsLegacyErasure);
+    }
+
+    for (ClassMember overriddenMember in _overriddenMembers) {
+      callback(
+          overriddenMember.getMember(membersBuilder), _declaredMember.isSetter);
+    }
+  }
+}
+
+class DelayedGetterSetterCheck implements DelayedCheck {
+  final SourceClassBuilder classBuilder;
+  final ClassMember getter;
+  final ClassMember setter;
+
+  const DelayedGetterSetterCheck(this.classBuilder, this.getter, this.setter);
+
+  @override
+  void check(ClassMembersBuilder membersBuilder) {
+    classBuilder.checkGetterSetter(membersBuilder.hierarchyBuilder.types,
+        getter.getMember(membersBuilder), setter.getMember(membersBuilder));
+  }
+}
+
+class DelayedTypeComputation {
+  final ClassMembersNodeBuilder builder;
+  final ClassMember declaredMember;
+  final Set<ClassMember> overriddenMembers;
+  bool _computed = false;
+
+  DelayedTypeComputation(
+      this.builder, this.declaredMember, this.overriddenMembers)
+      : assert(declaredMember.isSourceDeclaration);
+
+  void compute(ClassMembersBuilder membersBuilder) {
+    if (_computed) return;
+    declaredMember.inferType(membersBuilder);
+    _computed = true;
+    if (declaredMember.isField) {
+      builder.inferFieldSignature(
+          membersBuilder, declaredMember, overriddenMembers);
+    } else if (declaredMember.isGetter) {
+      builder.inferGetterSignature(
+          membersBuilder, declaredMember, overriddenMembers);
+    } else if (declaredMember.isSetter) {
+      builder.inferSetterSignature(
+          membersBuilder, declaredMember, overriddenMembers);
+    } else {
+      builder.inferMethodSignature(
+          membersBuilder, declaredMember, overriddenMembers);
+    }
+  }
+
+  @override
+  String toString() => 'DelayedTypeComputation('
+      '${builder.classBuilder.name},$declaredMember,$overriddenMembers)';
+}
diff --git a/pkg/front_end/lib/src/fasta/kernel/hierarchy/hierarchy_builder.dart b/pkg/front_end/lib/src/fasta/kernel/hierarchy/hierarchy_builder.dart
new file mode 100644
index 0000000..b40523a
--- /dev/null
+++ b/pkg/front_end/lib/src/fasta/kernel/hierarchy/hierarchy_builder.dart
@@ -0,0 +1,194 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library fasta.class_hierarchy_builder;
+
+import 'package:kernel/ast.dart';
+import 'package:kernel/class_hierarchy.dart' show ClassHierarchyBase;
+import 'package:kernel/core_types.dart' show CoreTypes;
+import 'package:kernel/src/types.dart' show Types;
+import 'package:kernel/type_algebra.dart' show Substitution, uniteNullabilities;
+
+import '../../builder/class_builder.dart';
+import '../../builder/type_builder.dart';
+import '../../loader.dart' show Loader;
+import '../../source/source_loader.dart' show SourceLoader;
+import 'hierarchy_node.dart';
+
+class ClassHierarchyBuilder implements ClassHierarchyBase {
+  final Map<Class, ClassHierarchyNode> nodes = <Class, ClassHierarchyNode>{};
+
+  final Map<ClassBuilder, Map<Class, Substitution>> substitutions =
+      <ClassBuilder, Map<Class, Substitution>>{};
+
+  final ClassBuilder objectClassBuilder;
+
+  final Loader loader;
+
+  final Class objectClass;
+
+  final Class futureClass;
+
+  final Class functionClass;
+
+  @override
+  final CoreTypes coreTypes;
+
+  late Types types;
+
+  ClassHierarchyBuilder(this.objectClassBuilder, this.loader, this.coreTypes)
+      : objectClass = objectClassBuilder.cls,
+        futureClass = coreTypes.futureClass,
+        functionClass = coreTypes.functionClass {
+    types = new Types(this);
+  }
+
+  void clear() {
+    nodes.clear();
+    substitutions.clear();
+  }
+
+  ClassHierarchyNode getNodeFromClassBuilder(ClassBuilder classBuilder) {
+    return nodes[classBuilder.cls] ??= new ClassHierarchyNodeBuilder(
+            this, classBuilder, substitutions[classBuilder] ??= {})
+        .build();
+  }
+
+  ClassHierarchyNode? getNodeFromTypeBuilder(TypeBuilder type) {
+    ClassBuilder? cls = getClass(type);
+    return cls == null ? null : getNodeFromClassBuilder(cls);
+  }
+
+  ClassHierarchyNode getNodeFromClass(Class cls) {
+    return nodes[cls] ??
+        getNodeFromClassBuilder(loader.computeClassBuilderFromTargetClass(cls));
+  }
+
+  Supertype? asSupertypeOf(InterfaceType subtype, Class supertype) {
+    if (subtype.classNode == supertype) {
+      return new Supertype(supertype, subtype.typeArguments);
+    }
+    ClassHierarchyNode clsNode = getNodeFromClass(subtype.classNode);
+    ClassHierarchyNode supertypeNode = getNodeFromClass(supertype);
+    List<Supertype> superclasses = clsNode.superclasses;
+    int depth = supertypeNode.depth;
+    if (depth < superclasses.length) {
+      Supertype superclass = superclasses[depth];
+      if (superclass.classNode == supertype) {
+        return Substitution.fromInterfaceType(subtype)
+            .substituteSupertype(superclass);
+      }
+    }
+    List<Supertype> superinterfaces = clsNode.interfaces;
+    for (int i = 0; i < superinterfaces.length; i++) {
+      Supertype superinterface = superinterfaces[i];
+      if (superinterface.classNode == supertype) {
+        return Substitution.fromInterfaceType(subtype)
+            .substituteSupertype(superinterface);
+      }
+    }
+    return null;
+  }
+
+  @override
+  InterfaceType getTypeAsInstanceOf(
+      InterfaceType type, Class superclass, Library clientLibrary) {
+    if (type.classNode == superclass) return type;
+    return asSupertypeOf(type, superclass)!
+        .asInterfaceType
+        .withDeclaredNullability(type.nullability);
+  }
+
+  @override
+  List<DartType>? getTypeArgumentsAsInstanceOf(
+      InterfaceType type, Class superclass) {
+    if (type.classNode == superclass) return type.typeArguments;
+    return asSupertypeOf(type, superclass)?.typeArguments;
+  }
+
+  @override
+  InterfaceType getLegacyLeastUpperBound(
+      InterfaceType type1, InterfaceType type2, Library clientLibrary) {
+    if (type1 == type2) return type1;
+
+    // LLUB(Null, List<dynamic>*) works differently for opt-in and opt-out
+    // libraries.  In opt-out libraries the legacy behavior is preserved, so
+    // LLUB(Null, List<dynamic>*) = List<dynamic>*.  In opt-out libraries the
+    // rules imply that LLUB(Null, List<dynamic>*) = List<dynamic>?.
+    if (!clientLibrary.isNonNullableByDefault) {
+      if (type1 is NullType) {
+        return type2;
+      }
+      if (type2 is NullType) {
+        return type1;
+      }
+    }
+
+    ClassHierarchyNode node1 = getNodeFromClass(type1.classNode);
+    ClassHierarchyNode node2 = getNodeFromClass(type2.classNode);
+    Set<ClassHierarchyNode> nodes1 = node1.computeAllSuperNodes(this).toSet();
+    List<ClassHierarchyNode> nodes2 = node2.computeAllSuperNodes(this);
+    List<ClassHierarchyNode> common = <ClassHierarchyNode>[];
+
+    for (int i = 0; i < nodes2.length; i++) {
+      ClassHierarchyNode node = nodes2[i];
+      // ignore: unnecessary_null_comparison
+      if (node == null) continue;
+      if (node.classBuilder.cls.isAnonymousMixin) {
+        // Never find unnamed mixin application in least upper bound.
+        continue;
+      }
+      if (nodes1.contains(node)) {
+        DartType candidate1 =
+            getTypeAsInstanceOf(type1, node.classBuilder.cls, clientLibrary);
+        DartType candidate2 =
+            getTypeAsInstanceOf(type2, node.classBuilder.cls, clientLibrary);
+        if (candidate1 == candidate2) {
+          common.add(node);
+        }
+      }
+    }
+
+    if (common.length == 1) {
+      return coreTypes.objectRawType(
+          uniteNullabilities(type1.nullability, type2.nullability));
+    }
+    common.sort(ClassHierarchyNode.compareMaxInheritancePath);
+
+    for (int i = 0; i < common.length - 1; i++) {
+      ClassHierarchyNode node = common[i];
+      if (node.maxInheritancePath != common[i + 1].maxInheritancePath) {
+        return getTypeAsInstanceOf(type1, node.classBuilder.cls, clientLibrary)
+            .withDeclaredNullability(
+                uniteNullabilities(type1.nullability, type2.nullability));
+      } else {
+        do {
+          i++;
+        } while (node.maxInheritancePath == common[i + 1].maxInheritancePath);
+      }
+    }
+    return coreTypes.objectRawType(
+        uniteNullabilities(type1.nullability, type2.nullability));
+  }
+
+  static ClassHierarchyBuilder build(ClassBuilder objectClass,
+      List<ClassBuilder> classes, SourceLoader loader, CoreTypes coreTypes) {
+    ClassHierarchyBuilder hierarchy =
+        new ClassHierarchyBuilder(objectClass, loader, coreTypes);
+    for (int i = 0; i < classes.length; i++) {
+      ClassBuilder classBuilder = classes[i];
+      if (!classBuilder.isPatch) {
+        hierarchy.nodes[classBuilder.cls] = new ClassHierarchyNodeBuilder(
+                hierarchy,
+                classBuilder,
+                hierarchy.substitutions[classBuilder] ??= {})
+            .build();
+      } else {
+        // TODO(ahe): Merge the injected members of patch into the hierarchy
+        // node of `cls.origin`.
+      }
+    }
+    return hierarchy;
+  }
+}
diff --git a/pkg/front_end/lib/src/fasta/kernel/hierarchy/hierarchy_node.dart b/pkg/front_end/lib/src/fasta/kernel/hierarchy/hierarchy_node.dart
new file mode 100644
index 0000000..a5e89b9
--- /dev/null
+++ b/pkg/front_end/lib/src/fasta/kernel/hierarchy/hierarchy_node.dart
@@ -0,0 +1,481 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library fasta.class_hierarchy_builder;
+
+import 'package:kernel/ast.dart';
+import 'package:kernel/src/legacy_erasure.dart';
+import 'package:kernel/src/nnbd_top_merge.dart';
+import 'package:kernel/src/norm.dart';
+import 'package:kernel/type_algebra.dart' show Substitution;
+
+import '../../../testing/id_testing_utils.dart' show typeToText;
+import '../../builder/builder.dart';
+import '../../builder/class_builder.dart';
+import '../../builder/named_type_builder.dart';
+import '../../builder/type_alias_builder.dart';
+import '../../builder/type_builder.dart';
+import '../../type_inference/type_schema.dart' show UnknownType;
+import 'hierarchy_builder.dart';
+import 'mixin_inferrer.dart';
+
+class ClassHierarchyNodeBuilder {
+  final ClassHierarchyBuilder hierarchy;
+
+  final ClassBuilder classBuilder;
+
+  bool hasNoSuchMethod = false;
+
+  final Map<Class, Substitution> substitutions;
+
+  ClassHierarchyNodeBuilder(
+      this.hierarchy, this.classBuilder, this.substitutions);
+
+  ClassBuilder get objectClass => hierarchy.objectClassBuilder;
+
+  ClassHierarchyNode build() {
+    assert(!classBuilder.isPatch);
+    ClassHierarchyNode? supernode;
+    if (objectClass != classBuilder.origin) {
+      supernode =
+          hierarchy.getNodeFromTypeBuilder(classBuilder.supertypeBuilder!);
+      if (supernode == null) {
+        supernode = hierarchy.getNodeFromClassBuilder(objectClass);
+      }
+      // ignore: unnecessary_null_comparison
+      assert(supernode != null);
+    }
+
+    List<Supertype> superclasses;
+
+    List<Supertype> interfaces;
+
+    int maxInheritancePath;
+
+    List<TypeBuilder>? directInterfaceBuilders;
+
+    if (classBuilder.isMixinApplication) {
+      inferMixinApplication();
+    }
+
+    if (supernode == null) {
+      // This should be Object.
+      superclasses = new List<Supertype>.filled(0, dummySupertype);
+      interfaces = new List<Supertype>.filled(0, dummySupertype);
+      maxInheritancePath = 0;
+    } else {
+      maxInheritancePath = supernode.maxInheritancePath + 1;
+
+      superclasses = new List<Supertype>.filled(
+          supernode.superclasses.length + 1, dummySupertype);
+      Supertype? supertype = classBuilder.supertypeBuilder!.buildSupertype(
+          classBuilder.library, classBuilder.charOffset, classBuilder.fileUri);
+      if (supertype == null) {
+        // If the superclass is not an interface type we use Object instead.
+        // A similar normalization is performed on [supernode] above.
+        supertype =
+            new Supertype(hierarchy.coreTypes.objectClass, const <DartType>[]);
+      }
+      superclasses.setRange(0, superclasses.length - 1,
+          substSupertypes(supertype, supernode.superclasses));
+      superclasses[superclasses.length - 1] = supertype;
+      if (!classBuilder.library.isNonNullableByDefault &&
+          supernode.classBuilder.library.isNonNullableByDefault) {
+        for (int i = 0; i < superclasses.length; i++) {
+          superclasses[i] = legacyErasureSupertype(superclasses[i]);
+        }
+      }
+
+      directInterfaceBuilders = ignoreFunction(classBuilder.interfaceBuilders);
+      if (classBuilder.isMixinApplication) {
+        if (directInterfaceBuilders == null) {
+          directInterfaceBuilders = <TypeBuilder>[
+            classBuilder.mixedInTypeBuilder!
+          ];
+        } else {
+          directInterfaceBuilders = <TypeBuilder>[
+            classBuilder.mixedInTypeBuilder!
+          ]..addAll(directInterfaceBuilders);
+        }
+      }
+
+      List<Supertype> superclassInterfaces = supernode.interfaces;
+      // ignore: unnecessary_null_comparison
+      if (superclassInterfaces != null) {
+        superclassInterfaces = substSupertypes(supertype, superclassInterfaces);
+      }
+
+      if (directInterfaceBuilders != null) {
+        interfaces = <Supertype>[];
+        // ignore: unnecessary_null_comparison
+        if (superclassInterfaces != null) {
+          for (int i = 0; i < superclassInterfaces.length; i++) {
+            addInterface(interfaces, superclasses, superclassInterfaces[i]);
+          }
+        }
+
+        for (int i = 0; i < directInterfaceBuilders.length; i++) {
+          Supertype? directInterface = directInterfaceBuilders[i]
+              .buildSupertype(classBuilder.library, classBuilder.charOffset,
+                  classBuilder.fileUri);
+          if (directInterface != null) {
+            addInterface(interfaces, superclasses, directInterface);
+            ClassHierarchyNode interfaceNode =
+                hierarchy.getNodeFromClass(directInterface.classNode);
+            // ignore: unnecessary_null_comparison
+            if (interfaceNode != null) {
+              if (maxInheritancePath < interfaceNode.maxInheritancePath + 1) {
+                maxInheritancePath = interfaceNode.maxInheritancePath + 1;
+              }
+
+              List<Supertype> types =
+                  substSupertypes(directInterface, interfaceNode.superclasses);
+              for (int i = 0; i < types.length; i++) {
+                addInterface(interfaces, superclasses, types[i]);
+              }
+              // ignore: unnecessary_null_comparison
+              if (interfaceNode.interfaces != null) {
+                List<Supertype> types =
+                    substSupertypes(directInterface, interfaceNode.interfaces);
+                for (int i = 0; i < types.length; i++) {
+                  addInterface(interfaces, superclasses, types[i]);
+                }
+              }
+            }
+          }
+        }
+        // ignore: unnecessary_null_comparison
+      } else if (superclassInterfaces != null &&
+          !classBuilder.library.isNonNullableByDefault &&
+          supernode.classBuilder.library.isNonNullableByDefault) {
+        interfaces = <Supertype>[];
+        for (int i = 0; i < superclassInterfaces.length; i++) {
+          addInterface(interfaces, superclasses, superclassInterfaces[i]);
+        }
+      } else {
+        interfaces = superclassInterfaces;
+      }
+    }
+
+    for (Supertype superclass in superclasses) {
+      recordSupertype(superclass);
+    }
+    // ignore: unnecessary_null_comparison
+    if (interfaces != null) {
+      for (Supertype superinterface in interfaces) {
+        recordSupertype(superinterface);
+      }
+    }
+
+    /*ClassHierarchyMemberNode memberNode =
+    buildMemberNode(supernode, directInterfaceBuilders);*/
+
+    return new ClassHierarchyNode(
+      classBuilder,
+      supernode,
+      directInterfaceBuilders,
+      /*classMemberMap,
+        classSetterMap,
+        interfaceMemberMap,
+        interfaceSetterMap,*/
+      superclasses,
+      interfaces,
+      maxInheritancePath,
+      /*hasNoSuchMethod,
+        dataForTesting,*/
+      /*memberNode*/
+    );
+  }
+
+  Supertype recordSupertype(Supertype supertype) {
+    debug?.log("In ${this.classBuilder.fullNameForErrors} "
+        "recordSupertype(${supertype})");
+    Class cls = supertype.classNode;
+    List<TypeParameter> supertypeTypeParameters = cls.typeParameters;
+    if (supertypeTypeParameters.isEmpty) {
+      substitutions[cls] = Substitution.empty;
+    } else {
+      List<DartType> arguments = supertype.typeArguments;
+      List<DartType> typeArguments =
+          new List<DartType>.filled(arguments.length, dummyDartType);
+      List<TypeParameter> typeParameters =
+          new List<TypeParameter>.filled(arguments.length, dummyTypeParameter);
+      for (int i = 0; i < arguments.length; i++) {
+        typeParameters[i] = supertypeTypeParameters[i];
+        typeArguments[i] = arguments[i];
+      }
+      substitutions[cls] =
+          Substitution.fromPairs(typeParameters, typeArguments);
+    }
+    return supertype;
+  }
+
+  List<Supertype> substSupertypes(
+      Supertype supertype, List<Supertype> supertypes) {
+    List<TypeParameter> typeVariables = supertype.classNode.typeParameters;
+    if (typeVariables.isEmpty) {
+      debug?.log("In ${this.classBuilder.fullNameForErrors} "
+          "$supertypes aren't substed");
+      return supertypes;
+    }
+    Map<TypeParameter, DartType> map = <TypeParameter, DartType>{};
+    List<DartType> arguments = supertype.typeArguments;
+    for (int i = 0; i < typeVariables.length; i++) {
+      map[typeVariables[i]] = arguments[i];
+    }
+    Substitution substitution = Substitution.fromMap(map);
+    List<Supertype>? result;
+    for (int i = 0; i < supertypes.length; i++) {
+      Supertype supertype = supertypes[i];
+      Supertype substituted = substitution.substituteSupertype(supertype);
+      if (supertype != substituted) {
+        debug?.log("In ${this.classBuilder.fullNameForErrors} $supertype"
+            " -> $substituted");
+        result ??= supertypes.toList();
+        result[i] = substituted;
+      } else {
+        debug?.log("In ${this.classBuilder.fullNameForErrors} "
+            "$supertype isn't substed");
+      }
+    }
+    return result ?? supertypes;
+  }
+
+  void addInterface(List<Supertype> interfaces, List<Supertype> superclasses,
+      Supertype type) {
+    // ignore: unnecessary_null_comparison
+    if (type == null) return null;
+    if (!classBuilder.library.isNonNullableByDefault) {
+      type = legacyErasureSupertype(type);
+    }
+    ClassHierarchyNode node = hierarchy.getNodeFromClass(type.classNode);
+    // ignore: unnecessary_null_comparison
+    if (node == null) return null;
+    int depth = node.depth;
+    int myDepth = superclasses.length;
+    Supertype? superclass = depth < myDepth ? superclasses[depth] : null;
+    if (superclass != null && superclass.classNode == type.classNode) {
+      // This is a potential conflict.
+      if (classBuilder.library.isNonNullableByDefault) {
+        superclass = nnbdTopMergeSupertype(
+            hierarchy.coreTypes,
+            normSupertype(hierarchy.coreTypes, superclass),
+            normSupertype(hierarchy.coreTypes, type));
+        if (superclass == null) {
+          // This is a conflict.
+          // TODO(johnniwinther): Report errors here instead of through
+          // the computation of the [ClassHierarchy].
+          superclass = superclasses[depth];
+        } else {
+          superclasses[depth] = superclass;
+        }
+      }
+      return;
+    } else {
+      for (int i = 0; i < interfaces.length; i++) {
+        // This is a quadratic algorithm, but normally, the number of
+        // interfaces is really small.
+        Supertype? interface = interfaces[i];
+        if (interface.classNode == type.classNode) {
+          // This is a potential conflict.
+          if (classBuilder.library.isNonNullableByDefault) {
+            interface = nnbdTopMergeSupertype(
+                hierarchy.coreTypes,
+                normSupertype(hierarchy.coreTypes, interface),
+                normSupertype(hierarchy.coreTypes, type));
+            if (interface == null) {
+              // This is a conflict.
+              // TODO(johnniwinther): Report errors here instead of through
+              // the computation of the [ClassHierarchy].
+              interface = interfaces[i];
+            } else {
+              interfaces[i] = interface;
+            }
+          }
+          return;
+        }
+      }
+    }
+    interfaces.add(type);
+  }
+
+  void inferMixinApplication() {
+    Class cls = classBuilder.cls;
+    Supertype? mixedInType = cls.mixedInType;
+    if (mixedInType == null) return;
+    List<DartType> typeArguments = mixedInType.typeArguments;
+    if (typeArguments.isEmpty || typeArguments.first is! UnknownType) return;
+    new BuilderMixinInferrer(
+            classBuilder,
+            hierarchy.coreTypes,
+            new TypeBuilderConstraintGatherer(hierarchy,
+                mixedInType.classNode.typeParameters, cls.enclosingLibrary))
+        .infer(cls);
+    List<TypeBuilder> inferredArguments = new List<TypeBuilder>.generate(
+        typeArguments.length,
+        (int i) => hierarchy.loader.computeTypeBuilder(typeArguments[i]),
+        growable: false);
+    NamedTypeBuilder mixedInTypeBuilder =
+        classBuilder.mixedInTypeBuilder as NamedTypeBuilder;
+    mixedInTypeBuilder.arguments = inferredArguments;
+  }
+
+  /// The class Function from dart:core is supposed to be ignored when used as
+  /// an interface.
+  List<TypeBuilder>? ignoreFunction(List<TypeBuilder>? interfaces) {
+    if (interfaces == null) return null;
+    for (int i = 0; i < interfaces!.length; i++) {
+      ClassBuilder? classBuilder = getClass(interfaces[i]);
+      if (classBuilder != null && classBuilder.cls == hierarchy.functionClass) {
+        if (interfaces.length == 1) {
+          return null;
+        } else {
+          interfaces = interfaces.toList();
+          interfaces.removeAt(i);
+          return ignoreFunction(interfaces);
+        }
+      }
+    }
+    return interfaces;
+  }
+}
+
+class ClassHierarchyNode {
+  /// The class corresponding to this hierarchy node.
+  final ClassBuilder classBuilder;
+
+  final ClassHierarchyNode? supernode;
+
+  final List<TypeBuilder>? directInterfaceBuilders;
+
+  /*/// All the members of this class including [classMembers] of its
+  /// superclasses. The members are sorted by [compareDeclarations].
+  final Map<Name, ClassMember> classMemberMap;
+
+  /// Similar to [classMembers] but for setters.
+  final Map<Name, ClassMember> classSetterMap;
+
+  /// All the interface members of this class including [interfaceMembers] of
+  /// its supertypes. The members are sorted by [compareDeclarations].
+  ///
+  /// In addition to the members of [classMembers] this also contains members
+  /// from interfaces.
+  ///
+  /// This may be null, in which case [classMembers] is the interface members.
+  final Map<Name, ClassMember>? interfaceMemberMap;
+
+  /// Similar to [interfaceMembers] but for setters.
+  ///
+  /// This may be null, in which case [classSetters] is the interface setters.
+  final Map<Name, ClassMember>? interfaceSetterMap;*/
+
+  /// All superclasses of [classBuilder] excluding itself. The classes are
+  /// sorted by depth from the root (Object) in ascending order.
+  final List<Supertype> superclasses;
+
+  /// The list of all classes implemented by [classBuilder] and its supertypes
+  /// excluding any classes from [superclasses].
+  final List<Supertype> interfaces;
+
+  /// The longest inheritance path from [classBuilder] to `Object`.
+  final int maxInheritancePath;
+
+  int get depth => superclasses.length;
+
+  /*final bool hasNoSuchMethod;
+
+  final ClassHierarchyNodeDataForTesting? dataForTesting;*/
+
+  //final ClassHierarchyMemberNode memberNode;
+
+  ClassHierarchyNode(
+    this.classBuilder,
+    this.supernode,
+    this.directInterfaceBuilders,
+    /*this.classMemberMap,
+      this.classSetterMap,
+      this.interfaceMemberMap,
+      this.interfaceSetterMap,*/
+    this.superclasses,
+    this.interfaces,
+    this.maxInheritancePath,
+    /*this.hasNoSuchMethod,
+      this.dataForTesting,*/
+    /*this.memberNode*/
+  );
+
+  /// Returns a list of all supertypes of [classBuilder], including this node.
+  List<ClassHierarchyNode> computeAllSuperNodes(
+      ClassHierarchyBuilder hierarchy) {
+    List<ClassHierarchyNode> result = [];
+    for (int i = 0; i < superclasses.length; i++) {
+      Supertype type = superclasses[i];
+      result.add(hierarchy.getNodeFromClass(type.classNode));
+    }
+    for (int i = 0; i < interfaces.length; i++) {
+      Supertype type = interfaces[i];
+      result.add(hierarchy.getNodeFromClass(type.classNode));
+    }
+    result.add(this);
+    return result;
+  }
+
+  @override
+  String toString() {
+    StringBuffer sb = new StringBuffer();
+    sb
+      ..write(classBuilder.fullNameForErrors)
+      ..writeln(":");
+    if (maxInheritancePath != this.depth) {
+      sb
+        ..write("  Longest path to Object: ")
+        ..writeln(maxInheritancePath);
+    }
+    sb..writeln("  superclasses:");
+    int depth = 0;
+    for (Supertype superclass in superclasses) {
+      sb.write("  " * (depth + 2));
+      if (depth != 0) sb.write("-> ");
+      sb.write(typeToText(superclass.asInterfaceType));
+      sb.writeln();
+      depth++;
+    }
+    // ignore: unnecessary_null_comparison
+    if (interfaces != null) {
+      sb.write("  interfaces:");
+      bool first = true;
+      for (Supertype i in interfaces) {
+        if (!first) sb.write(",");
+        sb.write(" ");
+        sb.write(typeToText(i.asInterfaceType));
+        first = false;
+      }
+      sb.writeln();
+    }
+    return "$sb";
+  }
+
+  static int compareMaxInheritancePath(
+      ClassHierarchyNode a, ClassHierarchyNode b) {
+    return b.maxInheritancePath.compareTo(a.maxInheritancePath);
+  }
+}
+
+ClassBuilder? getClass(TypeBuilder type) {
+  Builder? declaration = type.declaration;
+  if (declaration is TypeAliasBuilder) {
+    TypeAliasBuilder aliasBuilder = declaration;
+    NamedTypeBuilder namedBuilder = type as NamedTypeBuilder;
+    declaration = aliasBuilder.unaliasDeclaration(namedBuilder.arguments);
+  }
+  return declaration is ClassBuilder ? declaration : null;
+}
+
+const DebugLogger? debug =
+    const bool.fromEnvironment("debug.hierarchy") ? const DebugLogger() : null;
+
+class DebugLogger {
+  const DebugLogger();
+  void log(Object message) => print(message);
+}
diff --git a/pkg/front_end/lib/src/fasta/kernel/hierarchy/members_builder.dart b/pkg/front_end/lib/src/fasta/kernel/hierarchy/members_builder.dart
new file mode 100644
index 0000000..f50343a
--- /dev/null
+++ b/pkg/front_end/lib/src/fasta/kernel/hierarchy/members_builder.dart
@@ -0,0 +1,182 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library fasta.class_hierarchy_builder;
+
+import 'package:kernel/ast.dart';
+import 'package:kernel/class_hierarchy.dart' show ClassHierarchyMembers;
+
+import '../../builder/class_builder.dart';
+import '../../builder/field_builder.dart';
+import '../../builder/procedure_builder.dart';
+import '../../builder/type_builder.dart';
+import '../../source/source_class_builder.dart';
+import 'class_member.dart';
+import 'delayed.dart';
+import 'hierarchy_builder.dart';
+import 'hierarchy_node.dart';
+import 'members_node.dart';
+
+class ClassMembersBuilder implements ClassHierarchyMembers {
+  final ClassHierarchyBuilder hierarchyBuilder;
+
+  final Map<Class, ClassMembersNode> nodes = <Class, ClassMembersNode>{};
+
+  final List<DelayedTypeComputation> _delayedTypeComputations =
+      <DelayedTypeComputation>[];
+
+  final List<DelayedCheck> _delayedChecks = <DelayedCheck>[];
+
+  final List<ClassMember> _delayedMemberComputations = <ClassMember>[];
+
+  ClassMembersBuilder(this.hierarchyBuilder);
+
+  void clear() {
+    nodes.clear();
+    _delayedChecks.clear();
+    _delayedTypeComputations.clear();
+    _delayedMemberComputations.clear();
+  }
+
+  void registerDelayedTypeComputation(DelayedTypeComputation computation) {
+    _delayedTypeComputations.add(computation);
+  }
+
+  void registerOverrideCheck(SourceClassBuilder classBuilder,
+      ClassMember declaredMember, Set<ClassMember> overriddenMembers) {
+    _delayedChecks.add(new DelayedOverrideCheck(
+        classBuilder, declaredMember, overriddenMembers));
+  }
+
+  void registerGetterSetterCheck(
+      SourceClassBuilder classBuilder, ClassMember getter, ClassMember setter) {
+    _delayedChecks
+        .add(new DelayedGetterSetterCheck(classBuilder, getter, setter));
+  }
+
+  void registerMemberComputation(ClassMember member) {
+    _delayedMemberComputations.add(member);
+  }
+
+  List<DelayedTypeComputation> takeDelayedTypeComputations() {
+    List<DelayedTypeComputation> list = _delayedTypeComputations.toList();
+    _delayedTypeComputations.clear();
+    return list;
+  }
+
+  List<DelayedCheck> takeDelayedChecks() {
+    List<DelayedCheck> list = _delayedChecks.toList();
+    _delayedChecks.clear();
+    return list;
+  }
+
+  List<ClassMember> takeDelayedMemberComputations() {
+    List<ClassMember> list = _delayedMemberComputations.toList();
+    _delayedMemberComputations.clear();
+    return list;
+  }
+
+  void inferFieldType(SourceFieldBuilder declaredMember,
+      Iterable<ClassMember> overriddenMembers) {
+    ClassMembersNodeBuilder.inferFieldType(
+        hierarchyBuilder,
+        this,
+        declaredMember.classBuilder as SourceClassBuilder,
+        declaredMember,
+        overriddenMembers);
+  }
+
+  void inferGetterType(SourceProcedureBuilder declaredMember,
+      Iterable<ClassMember> overriddenMembers) {
+    ClassMembersNodeBuilder.inferGetterType(
+        hierarchyBuilder,
+        this,
+        declaredMember.classBuilder as SourceClassBuilder,
+        declaredMember,
+        overriddenMembers);
+  }
+
+  void inferSetterType(SourceProcedureBuilder declaredMember,
+      Iterable<ClassMember> overriddenMembers) {
+    ClassMembersNodeBuilder.inferSetterType(
+        hierarchyBuilder,
+        this,
+        declaredMember.classBuilder as SourceClassBuilder,
+        declaredMember,
+        overriddenMembers);
+  }
+
+  void inferMethodType(SourceProcedureBuilder declaredMember,
+      Iterable<ClassMember> overriddenMembers) {
+    ClassMembersNodeBuilder.inferMethodType(
+        hierarchyBuilder,
+        this,
+        declaredMember.classBuilder as SourceClassBuilder,
+        declaredMember,
+        overriddenMembers);
+  }
+
+  ClassMembersNode getNodeFromClassBuilder(ClassBuilder classBuilder) {
+    return nodes[classBuilder.cls] ??= new ClassMembersNodeBuilder(
+            this,
+            hierarchyBuilder.getNodeFromClassBuilder(classBuilder),
+            hierarchyBuilder.substitutions[classBuilder] ??= {})
+        .build();
+  }
+
+  ClassMembersNode? getNodeFromTypeBuilder(TypeBuilder type) {
+    ClassBuilder? cls = getClass(type);
+    return cls == null ? null : getNodeFromClassBuilder(cls);
+  }
+
+  ClassMembersNode getNodeFromClass(Class cls) {
+    return nodes[cls] ??
+        getNodeFromClassBuilder(
+            hierarchyBuilder.loader.computeClassBuilderFromTargetClass(cls));
+  }
+
+  @override
+  Member? getInterfaceMember(Class cls, Name name, {bool setter: false}) {
+    return getNodeFromClass(cls)
+        .getInterfaceMember(name, setter)
+        ?.getMember(this);
+  }
+
+  ClassMember? getInterfaceClassMember(Class cls, Name name,
+      {bool setter: false}) {
+    return getNodeFromClass(cls).getInterfaceMember(name, setter);
+  }
+
+  static ClassMembersBuilder build(
+      ClassHierarchyBuilder hierarchyBuilder, List<ClassBuilder> classes) {
+    ClassMembersBuilder membersBuilder =
+        new ClassMembersBuilder(hierarchyBuilder);
+    for (int i = 0; i < classes.length; i++) {
+      ClassBuilder classBuilder = classes[i];
+      if (!classBuilder.isPatch) {
+        membersBuilder.nodes[classBuilder.cls] = new ClassMembersNodeBuilder(
+                membersBuilder,
+                hierarchyBuilder.getNodeFromClassBuilder(classBuilder),
+                hierarchyBuilder.substitutions[classBuilder] ??= {})
+            .build();
+      } else {
+        // TODO(ahe): Merge the injected members of patch into the hierarchy
+        // node of `cls.origin`.
+      }
+    }
+    return membersBuilder;
+  }
+
+  void computeTypes() {
+    List<DelayedTypeComputation> typeComputations =
+        takeDelayedTypeComputations();
+    for (int i = 0; i < typeComputations.length; i++) {
+      typeComputations[i].compute(this);
+    }
+  }
+}
+
+int compareNamedParameters(VariableDeclaration a, VariableDeclaration b) {
+  return a.name!.compareTo(b.name!);
+}
diff --git a/pkg/front_end/lib/src/fasta/kernel/hierarchy/members_node.dart b/pkg/front_end/lib/src/fasta/kernel/hierarchy/members_node.dart
new file mode 100644
index 0000000..b2fc124
--- /dev/null
+++ b/pkg/front_end/lib/src/fasta/kernel/hierarchy/members_node.dart
@@ -0,0 +1,2883 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library fasta.class_hierarchy_builder;
+
+import 'package:kernel/ast.dart';
+import 'package:kernel/class_hierarchy.dart' show ClassHierarchy;
+import 'package:kernel/src/legacy_erasure.dart';
+import 'package:kernel/src/nnbd_top_merge.dart';
+import 'package:kernel/src/norm.dart';
+import 'package:kernel/type_algebra.dart' show Substitution;
+
+import '../../../base/common.dart';
+import '../../builder/builder.dart';
+import '../../builder/class_builder.dart';
+import '../../builder/field_builder.dart';
+import '../../builder/formal_parameter_builder.dart';
+import '../../builder/library_builder.dart';
+import '../../builder/member_builder.dart';
+import '../../builder/named_type_builder.dart';
+import '../../builder/procedure_builder.dart';
+import '../../builder/type_alias_builder.dart';
+import '../../builder/type_builder.dart';
+import '../../builder/type_declaration_builder.dart';
+import '../../messages.dart'
+    show
+        LocatedMessage,
+        messageDeclaredMemberConflictsWithInheritedMember,
+        messageDeclaredMemberConflictsWithInheritedMemberCause,
+        messageDeclaredMemberConflictsWithOverriddenMembersCause,
+        messageInheritedMembersConflict,
+        messageInheritedMembersConflictCause1,
+        messageInheritedMembersConflictCause2,
+        messageStaticAndInstanceConflict,
+        messageStaticAndInstanceConflictCause,
+        templateCantInferTypesDueToNoCombinedSignature,
+        templateCantInferReturnTypeDueToNoCombinedSignature,
+        templateCantInferTypeDueToNoCombinedSignature,
+        templateDuplicatedDeclaration,
+        templateDuplicatedDeclarationCause,
+        templateMissingImplementationCause,
+        templateMissingImplementationNotAbstract;
+import '../../names.dart' show noSuchMethodName;
+import '../../scope.dart' show Scope;
+import '../../source/source_class_builder.dart';
+import '../combined_member_signature.dart';
+import '../member_covariance.dart';
+import 'class_member.dart';
+import 'delayed.dart';
+import 'hierarchy_builder.dart';
+import 'hierarchy_node.dart';
+import 'members_builder.dart';
+
+class ClassMembersNodeBuilder {
+  final ClassHierarchyNode _hierarchyNode;
+  final ClassMembersBuilder _membersBuilder;
+
+  bool hasNoSuchMethod = false;
+
+  final Map<Class, Substitution> substitutions;
+
+  ClassMembersNodeBuilder(
+      this._membersBuilder, this._hierarchyNode, this.substitutions);
+
+  ClassHierarchyBuilder get hierarchy => _membersBuilder.hierarchyBuilder;
+
+  ClassBuilder get objectClass => hierarchy.objectClassBuilder;
+
+  ClassBuilder get classBuilder => _hierarchyNode.classBuilder;
+
+  bool get shouldModifyKernel =>
+      classBuilder.library.loader == hierarchy.loader;
+
+  ClassMember? checkInheritanceConflict(ClassMember a, ClassMember b) {
+    if (a.isStatic || a.isProperty != b.isProperty) {
+      reportInheritanceConflict(a, b);
+      return a;
+    }
+    return null;
+  }
+
+  static void inferMethodType(
+      ClassHierarchyBuilder hierarchyBuilder,
+      ClassMembersBuilder membersBuilder,
+      SourceClassBuilder classBuilder,
+      SourceProcedureBuilder declaredMember,
+      Iterable<ClassMember> overriddenMembers) {
+    assert(!declaredMember.isGetter && !declaredMember.isSetter);
+    if (declaredMember.classBuilder == classBuilder &&
+        (declaredMember.returnType == null ||
+            declaredMember.formals != null &&
+                declaredMember.formals!
+                    .any((parameter) => parameter.type == null))) {
+      Procedure declaredProcedure = declaredMember.member as Procedure;
+      FunctionNode declaredFunction = declaredProcedure.function;
+      List<TypeParameter> declaredTypeParameters =
+          declaredFunction.typeParameters;
+      List<VariableDeclaration> declaredPositional =
+          declaredFunction.positionalParameters;
+      List<VariableDeclaration> declaredNamed =
+          declaredFunction.namedParameters;
+      declaredNamed = declaredNamed.toList()..sort(compareNamedParameters);
+
+      DartType? inferredReturnType;
+      Map<FormalParameterBuilder, DartType?> inferredParameterTypes = {};
+
+      Set<ClassMember> overriddenMemberSet =
+          toSet(classBuilder, overriddenMembers);
+      CombinedClassMemberSignature combinedMemberSignature =
+          new CombinedClassMemberSignature(
+              membersBuilder, classBuilder, overriddenMemberSet.toList(),
+              forSetter: false);
+      FunctionType? combinedMemberSignatureType = combinedMemberSignature
+              .getCombinedSignatureTypeInContext(declaredTypeParameters)
+          as FunctionType?;
+
+      bool cantInferReturnType = false;
+      List<FormalParameterBuilder>? cantInferParameterTypes;
+
+      if (declaredMember.returnType == null) {
+        if (combinedMemberSignatureType == null) {
+          inferredReturnType = const InvalidType();
+          cantInferReturnType = true;
+        } else {
+          inferredReturnType = combinedMemberSignatureType.returnType;
+        }
+      }
+      if (declaredMember.formals != null) {
+        for (int i = 0; i < declaredPositional.length; i++) {
+          FormalParameterBuilder declaredParameter = declaredMember.formals![i];
+          if (declaredParameter.type != null) {
+            continue;
+          }
+
+          DartType? inferredParameterType;
+          if (combinedMemberSignatureType == null) {
+            inferredParameterType = const InvalidType();
+            cantInferParameterTypes ??= [];
+            cantInferParameterTypes.add(declaredParameter);
+          } else if (i <
+              combinedMemberSignatureType.positionalParameters.length) {
+            inferredParameterType =
+                combinedMemberSignatureType.positionalParameters[i];
+          }
+          inferredParameterTypes[declaredParameter] = inferredParameterType;
+        }
+
+        Map<String, DartType>? namedParameterTypes;
+        for (int i = declaredPositional.length;
+            i < declaredMember.formals!.length;
+            i++) {
+          FormalParameterBuilder declaredParameter = declaredMember.formals![i];
+          if (declaredParameter.type != null) {
+            continue;
+          }
+
+          DartType? inferredParameterType;
+          if (combinedMemberSignatureType == null) {
+            inferredParameterType = const InvalidType();
+            cantInferParameterTypes ??= [];
+            cantInferParameterTypes.add(declaredParameter);
+          } else {
+            if (namedParameterTypes == null) {
+              namedParameterTypes = {};
+              for (NamedType namedType
+                  in combinedMemberSignatureType.namedParameters) {
+                namedParameterTypes[namedType.name] = namedType.type;
+              }
+            }
+            inferredParameterType = namedParameterTypes[declaredParameter.name];
+          }
+          inferredParameterTypes[declaredParameter] = inferredParameterType;
+        }
+      }
+
+      if ((cantInferReturnType && cantInferParameterTypes != null) ||
+          (cantInferParameterTypes != null &&
+              cantInferParameterTypes.length > 1)) {
+        reportCantInferTypes(classBuilder, declaredMember, overriddenMembers);
+      } else if (cantInferReturnType) {
+        reportCantInferReturnType(
+            classBuilder, declaredMember, overriddenMembers);
+      } else if (cantInferParameterTypes != null) {
+        reportCantInferParameterType(
+            classBuilder, cantInferParameterTypes.single, overriddenMembers);
+      }
+
+      if (declaredMember.returnType == null) {
+        inferredReturnType ??= const DynamicType();
+        declaredFunction.returnType = inferredReturnType;
+      }
+      if (declaredMember.formals != null) {
+        for (FormalParameterBuilder declaredParameter
+            in declaredMember.formals!) {
+          if (declaredParameter.type == null) {
+            DartType inferredParameterType =
+                inferredParameterTypes[declaredParameter] ??
+                    const DynamicType();
+            declaredParameter.variable!.type = inferredParameterType;
+          }
+        }
+      }
+    }
+  }
+
+  void inferMethodSignature(ClassMembersBuilder membersBuilder,
+      ClassMember declaredMember, Iterable<ClassMember> overriddenMembers) {
+    assert(!declaredMember.isGetter && !declaredMember.isSetter);
+    // Trigger computation of method type.
+    Procedure declaredProcedure =
+        declaredMember.getMember(membersBuilder) as Procedure;
+    for (ClassMember overriddenMember
+        in toSet(declaredMember.classBuilder, overriddenMembers)) {
+      Covariance covariance = overriddenMember.getCovariance(membersBuilder);
+      covariance.applyCovariance(declaredProcedure);
+    }
+  }
+
+  void inferGetterSignature(ClassMembersBuilder membersBuilder,
+      ClassMember declaredMember, Iterable<ClassMember> overriddenMembers) {
+    assert(declaredMember.isGetter);
+    // Trigger computation of the getter type.
+    declaredMember.getMember(membersBuilder);
+    // Otherwise nothing to do. Getters have no variance.
+  }
+
+  void inferSetterSignature(ClassMembersBuilder membersBuilder,
+      ClassMember declaredMember, Iterable<ClassMember> overriddenMembers) {
+    assert(declaredMember.isSetter);
+    // Trigger computation of the getter type.
+    Procedure declaredSetter =
+        declaredMember.getMember(membersBuilder) as Procedure;
+    for (ClassMember overriddenMember
+        in toSet(declaredMember.classBuilder, overriddenMembers)) {
+      Covariance covariance = overriddenMember.getCovariance(membersBuilder);
+      covariance.applyCovariance(declaredSetter);
+    }
+  }
+
+  static void inferGetterType(
+      ClassHierarchyBuilder hierarchyBuilder,
+      ClassMembersBuilder membersBuilder,
+      SourceClassBuilder classBuilder,
+      SourceProcedureBuilder declaredMember,
+      Iterable<ClassMember> overriddenMembers) {
+    assert(declaredMember.isGetter);
+    if (declaredMember.classBuilder == classBuilder &&
+        declaredMember.returnType == null) {
+      DartType? inferredType;
+      overriddenMembers = toSet(classBuilder, overriddenMembers);
+
+      List<ClassMember> overriddenGetters = [];
+      List<ClassMember> overriddenSetters = [];
+      for (ClassMember overriddenMember in overriddenMembers) {
+        if (overriddenMember.forSetter) {
+          overriddenSetters.add(overriddenMember);
+        } else {
+          overriddenGetters.add(overriddenMember);
+        }
+      }
+
+      void inferFrom(List<ClassMember> members, {required bool forSetter}) {
+        // ignore: unnecessary_null_comparison
+        assert(forSetter != null);
+        CombinedClassMemberSignature combinedMemberSignature =
+            new CombinedClassMemberSignature(
+                membersBuilder, classBuilder, members,
+                forSetter: forSetter);
+        DartType? combinedMemberSignatureType =
+            combinedMemberSignature.combinedMemberSignatureType;
+        if (combinedMemberSignatureType == null) {
+          inferredType = const InvalidType();
+          reportCantInferReturnType(classBuilder, declaredMember, members);
+        } else {
+          inferredType = combinedMemberSignatureType;
+        }
+      }
+
+      if (overriddenGetters.isNotEmpty) {
+        // 1) The return type of a getter, parameter type of a setter or type
+        // of a field which overrides/implements only one or more getters is
+        // inferred to be the return type of the combined member signature of
+        // said getter in the direct superinterfaces.
+
+        // 2) The return type of a getter which overrides/implements both a
+        // setter and a getter is inferred to be the return type of the
+        // combined member signature of said getter in the direct
+        // superinterfaces.
+        inferFrom(overriddenGetters, forSetter: false);
+      } else {
+        // The return type of a getter, parameter type of a setter or type of
+        // a field which overrides/implements only one or more setters is
+        // inferred to be the parameter type of the combined member signature
+        // of said setter in the direct superinterfaces.
+        inferFrom(overriddenSetters, forSetter: true);
+      }
+
+      declaredMember.procedure.function.returnType =
+          inferredType ?? const DynamicType();
+    }
+  }
+
+  static void inferSetterType(
+      ClassHierarchyBuilder hierarchyBuilder,
+      ClassMembersBuilder membersBuilder,
+      SourceClassBuilder classBuilder,
+      SourceProcedureBuilder declaredMember,
+      Iterable<ClassMember> overriddenMembers) {
+    assert(declaredMember.isSetter);
+    FormalParameterBuilder parameter = declaredMember.formals!.first;
+    if (declaredMember.classBuilder == classBuilder && parameter.type == null) {
+      DartType? inferredType;
+
+      overriddenMembers = toSet(classBuilder, overriddenMembers);
+
+      List<ClassMember> overriddenGetters = [];
+      List<ClassMember> overriddenSetters = [];
+      for (ClassMember overriddenMember in overriddenMembers) {
+        if (overriddenMember.forSetter) {
+          overriddenSetters.add(overriddenMember);
+        } else {
+          overriddenGetters.add(overriddenMember);
+        }
+      }
+
+      void inferFrom(List<ClassMember> members, {required bool forSetter}) {
+        // ignore: unnecessary_null_comparison
+        assert(forSetter != null);
+        CombinedClassMemberSignature combinedMemberSignature =
+            new CombinedClassMemberSignature(
+                membersBuilder, classBuilder, members,
+                forSetter: forSetter);
+        DartType? combinedMemberSignatureType =
+            combinedMemberSignature.combinedMemberSignatureType;
+        if (combinedMemberSignatureType == null) {
+          inferredType = const InvalidType();
+          reportCantInferReturnType(classBuilder, declaredMember, members);
+        } else {
+          inferredType = combinedMemberSignatureType;
+        }
+      }
+
+      if (overriddenSetters.isNotEmpty) {
+        // 1) The return type of a getter, parameter type of a setter or type
+        // of a field which overrides/implements only one or more setters is
+        // inferred to be the parameter type of the combined member signature
+        // of said setter in the direct superinterfaces.
+        //
+        // 2) The parameter type of a setter which overrides/implements both a
+        // setter and a getter is inferred to be the parameter type of the
+        // combined member signature of said setter in the direct
+        // superinterfaces.
+        inferFrom(overriddenSetters, forSetter: true);
+      } else {
+        // The return type of a getter, parameter type of a setter or type of
+        // a field which overrides/implements only one or more getters is
+        // inferred to be the return type of the combined member signature of
+        // said getter in the direct superinterfaces.
+        inferFrom(overriddenGetters, forSetter: false);
+      }
+
+      parameter.variable!.type = inferredType ?? const DynamicType();
+    }
+  }
+
+  /// Merge the [inheritedType] with the currently [inferredType] using
+  /// nnbd-top-merge or legacy-top-merge depending on whether [classBuilder] is
+  /// defined in an opt-in or opt-out library. If the types could not be merged
+  /// `null` is returned and an error should be reported by the caller.
+  static DartType? mergeTypeInLibrary(
+      ClassHierarchyBuilder hierarchy,
+      ClassBuilder classBuilder,
+      DartType? inferredType,
+      DartType inheritedType) {
+    if (classBuilder.library.isNonNullableByDefault) {
+      if (inferredType == null) {
+        return inheritedType;
+      } else {
+        return nnbdTopMerge(
+            hierarchy.coreTypes,
+            norm(hierarchy.coreTypes, inferredType),
+            norm(hierarchy.coreTypes, inheritedType));
+      }
+    } else {
+      inheritedType = legacyErasure(inheritedType);
+      if (inferredType == null) {
+        return inheritedType;
+      } else {
+        if (inferredType is DynamicType &&
+            inheritedType == hierarchy.coreTypes.objectLegacyRawType) {
+          return inferredType;
+        } else if (inheritedType is DynamicType &&
+            inferredType == hierarchy.coreTypes.objectLegacyRawType) {
+          return inheritedType;
+        }
+        if (inferredType != inheritedType) {
+          return null;
+        }
+        return inferredType;
+      }
+    }
+  }
+
+  /// Infers the field type of [fieldBuilder] based on [overriddenMembers].
+  static void inferFieldType(
+      ClassHierarchyBuilder hierarchyBuilder,
+      ClassMembersBuilder membersBuilder,
+      SourceClassBuilder classBuilder,
+      SourceFieldBuilder fieldBuilder,
+      Iterable<ClassMember> overriddenMembers) {
+    if (fieldBuilder.classBuilder == classBuilder &&
+        fieldBuilder.type == null) {
+      DartType? inferredType;
+
+      overriddenMembers = toSet(classBuilder, overriddenMembers);
+      List<ClassMember> overriddenGetters = [];
+      List<ClassMember> overriddenSetters = [];
+      for (ClassMember overriddenMember in overriddenMembers) {
+        if (overriddenMember.forSetter) {
+          overriddenSetters.add(overriddenMember);
+        } else {
+          overriddenGetters.add(overriddenMember);
+        }
+      }
+
+      DartType? inferFrom(List<ClassMember> members,
+          {required bool forSetter}) {
+        // ignore: unnecessary_null_comparison
+        assert(forSetter != null);
+        CombinedClassMemberSignature combinedMemberSignature =
+            new CombinedClassMemberSignature(
+                membersBuilder, classBuilder, members,
+                forSetter: forSetter);
+        return combinedMemberSignature.combinedMemberSignatureType;
+      }
+
+      DartType? combinedMemberSignatureType;
+      if (fieldBuilder.isAssignable &&
+          overriddenGetters.isNotEmpty &&
+          overriddenSetters.isNotEmpty) {
+        // The type of a non-final field which overrides/implements both a
+        // setter and a getter is inferred to be the parameter type of the
+        // combined member signature of said setter in the direct
+        // superinterfaces, if this type is the same as the return type of the
+        // combined member signature of said getter in the direct
+        // superinterfaces. If the types are not the same then inference fails
+        // with an error.
+        DartType? getterType = inferFrom(overriddenGetters, forSetter: false);
+        DartType? setterType = inferFrom(overriddenSetters, forSetter: true);
+        if (getterType == setterType) {
+          combinedMemberSignatureType = getterType;
+        }
+      } else if (overriddenGetters.isNotEmpty) {
+        // 1) The return type of a getter, parameter type of a setter or type
+        // of a field which overrides/implements only one or more getters is
+        // inferred to be the return type of the combined member signature of
+        // said getter in the direct superinterfaces.
+        //
+        // 2) The type of a final field which overrides/implements both a
+        // setter and a getter is inferred to be the return type of the
+        // combined member signature of said getter in the direct
+        // superinterfaces.
+        combinedMemberSignatureType =
+            inferFrom(overriddenGetters, forSetter: false);
+      } else {
+        // The return type of a getter, parameter type of a setter or type of
+        // a field which overrides/implements only one or more setters is
+        // inferred to be the parameter type of the combined member signature
+        // of said setter in the direct superinterfaces.
+        combinedMemberSignatureType =
+            inferFrom(overriddenSetters, forSetter: true);
+      }
+
+      if (combinedMemberSignatureType == null) {
+        inferredType = const InvalidType();
+        reportCantInferFieldType(classBuilder, fieldBuilder, overriddenMembers);
+      } else {
+        inferredType = combinedMemberSignatureType;
+      }
+
+      fieldBuilder.fieldType = inferredType;
+    }
+  }
+
+  /// Infers the field signature of [declaredMember] based on
+  /// [overriddenMembers].
+  void inferFieldSignature(ClassMembersBuilder membersBuilder,
+      ClassMember declaredMember, Iterable<ClassMember> overriddenMembers) {
+    Field declaredField = declaredMember.getMember(membersBuilder) as Field;
+    for (ClassMember overriddenMember
+        in toSet(declaredMember.classBuilder, overriddenMembers)) {
+      Covariance covariance = overriddenMember.getCovariance(membersBuilder);
+      covariance.applyCovariance(declaredField);
+    }
+  }
+
+  void reportInheritanceConflict(ClassMember a, ClassMember b) {
+    String name = a.fullNameForErrors;
+    if (a.classBuilder != b.classBuilder) {
+      if (a.classBuilder == classBuilder) {
+        classBuilder.addProblem(
+            messageDeclaredMemberConflictsWithInheritedMember,
+            a.charOffset,
+            name.length,
+            context: <LocatedMessage>[
+              messageDeclaredMemberConflictsWithInheritedMemberCause
+                  .withLocation(b.fileUri, b.charOffset, name.length)
+            ]);
+      } else if (b.classBuilder == classBuilder) {
+        classBuilder.addProblem(
+            messageDeclaredMemberConflictsWithInheritedMember,
+            b.charOffset,
+            name.length,
+            context: <LocatedMessage>[
+              messageDeclaredMemberConflictsWithInheritedMemberCause
+                  .withLocation(a.fileUri, a.charOffset, name.length)
+            ]);
+      } else {
+        classBuilder.addProblem(messageInheritedMembersConflict,
+            classBuilder.charOffset, classBuilder.fullNameForErrors.length,
+            context: _inheritedConflictContext(a, b));
+      }
+    } else if (a.isStatic != b.isStatic) {
+      ClassMember staticMember;
+      ClassMember instanceMember;
+      if (a.isStatic) {
+        staticMember = a;
+        instanceMember = b;
+      } else {
+        staticMember = b;
+        instanceMember = a;
+      }
+      classBuilder.library.addProblem(messageStaticAndInstanceConflict,
+          staticMember.charOffset, name.length, staticMember.fileUri,
+          context: <LocatedMessage>[
+            messageStaticAndInstanceConflictCause.withLocation(
+                instanceMember.fileUri, instanceMember.charOffset, name.length)
+          ]);
+    } else {
+      // This message can be reported twice (when merging localMembers with
+      // classSetters, or localSetters with classMembers). By ensuring that
+      // we always report the one with higher charOffset as the duplicate,
+      // the message duplication logic ensures that we only report this
+      // problem once.
+      ClassMember existing;
+      ClassMember duplicate;
+      assert(a.fileUri == b.fileUri);
+      if (a.charOffset < b.charOffset) {
+        existing = a;
+        duplicate = b;
+      } else {
+        existing = b;
+        duplicate = a;
+      }
+      classBuilder.library.addProblem(
+          templateDuplicatedDeclaration.withArguments(name),
+          duplicate.charOffset,
+          name.length,
+          duplicate.fileUri,
+          context: <LocatedMessage>[
+            templateDuplicatedDeclarationCause.withArguments(name).withLocation(
+                existing.fileUri, existing.charOffset, name.length)
+          ]);
+    }
+  }
+
+  ClassMembersNode build() {
+    ClassMembersNode? supernode = _hierarchyNode.supernode != null
+        ? _membersBuilder
+            .getNodeFromClassBuilder(_hierarchyNode.supernode!.classBuilder)
+        : null;
+    List<TypeBuilder>? directInterfaceBuilders =
+        _hierarchyNode.directInterfaceBuilders;
+
+    /// Set to `true` if the class needs interfaces, that is, if it has any
+    /// members where the interface member is different from its corresponding
+    /// class members.
+    ///
+    /// This is an optimization to avoid unnecessary computation of interface
+    /// members.
+    bool hasInterfaces = false;
+
+    Map<Name, Tuple> memberMap = {};
+
+    Scope scope = classBuilder.scope;
+
+    for (Builder builder in scope.localMembers) {
+      MemberBuilder memberBuilder = builder as MemberBuilder;
+      for (ClassMember classMember in memberBuilder.localMembers) {
+        if (classMember.isAbstract) {
+          hasInterfaces = true;
+        }
+        Tuple? tuple = memberMap[classMember.name];
+        if (tuple == null) {
+          memberMap[classMember.name] = new Tuple.declareMember(classMember);
+        } else {
+          tuple.declaredMember = classMember;
+        }
+      }
+      for (ClassMember classMember in memberBuilder.localSetters) {
+        if (classMember.isAbstract) {
+          hasInterfaces = true;
+        }
+        Tuple? tuple = memberMap[classMember.name];
+        if (tuple == null) {
+          memberMap[classMember.name] = new Tuple.declareSetter(classMember);
+        } else {
+          tuple.declaredSetter = classMember;
+        }
+      }
+    }
+
+    for (MemberBuilder memberBuilder in scope.localSetters) {
+      for (ClassMember classMember in memberBuilder.localMembers) {
+        if (classMember.isAbstract) {
+          hasInterfaces = true;
+        }
+        Tuple? tuple = memberMap[classMember.name];
+        if (tuple == null) {
+          memberMap[classMember.name] = new Tuple.declareMember(classMember);
+        } else {
+          tuple.declaredMember = classMember;
+        }
+      }
+      for (ClassMember classMember in memberBuilder.localSetters) {
+        if (classMember.isAbstract) {
+          hasInterfaces = true;
+        }
+        Tuple? tuple = memberMap[classMember.name];
+        if (tuple == null) {
+          memberMap[classMember.name] = new Tuple.declareSetter(classMember);
+        } else {
+          tuple.declaredSetter = classMember;
+        }
+      }
+    }
+
+    if (classBuilder.isMixinApplication) {
+      TypeBuilder mixedInTypeBuilder = classBuilder.mixedInTypeBuilder!;
+      TypeDeclarationBuilder mixin = mixedInTypeBuilder.declaration!;
+      while (mixin.isNamedMixinApplication) {
+        ClassBuilder named = mixin as ClassBuilder;
+        mixedInTypeBuilder = named.mixedInTypeBuilder!;
+        mixin = mixedInTypeBuilder.declaration!;
+      }
+      if (mixin is TypeAliasBuilder) {
+        TypeAliasBuilder aliasBuilder = mixin;
+        NamedTypeBuilder namedBuilder = mixedInTypeBuilder as NamedTypeBuilder;
+        mixin = aliasBuilder.unaliasDeclaration(namedBuilder.arguments,
+            isUsedAsClass: true,
+            usedAsClassCharOffset: namedBuilder.charOffset,
+            usedAsClassFileUri: namedBuilder.fileUri)!;
+      }
+      if (mixin is ClassBuilder) {
+        scope = mixin.scope.computeMixinScope();
+
+        for (Builder builder in scope.localMembers) {
+          MemberBuilder memberBuilder = builder as MemberBuilder;
+          for (ClassMember classMember in memberBuilder.localMembers) {
+            if (classMember.isAbstract) {
+              hasInterfaces = true;
+            }
+            Tuple? tuple = memberMap[classMember.name];
+            if (tuple == null) {
+              memberMap[classMember.name] = new Tuple.mixInMember(classMember);
+            } else {
+              tuple.mixedInMember = classMember;
+            }
+          }
+          for (ClassMember classMember in memberBuilder.localSetters) {
+            if (classMember.isAbstract) {
+              hasInterfaces = true;
+            }
+            Tuple? tuple = memberMap[classMember.name];
+            if (tuple == null) {
+              memberMap[classMember.name] = new Tuple.mixInSetter(classMember);
+            } else {
+              tuple.mixedInSetter = classMember;
+            }
+          }
+        }
+
+        for (MemberBuilder memberBuilder in scope.localSetters) {
+          for (ClassMember classMember in memberBuilder.localMembers) {
+            if (classMember.isAbstract) {
+              hasInterfaces = true;
+            }
+            Tuple? tuple = memberMap[classMember.name];
+            if (tuple == null) {
+              memberMap[classMember.name] = new Tuple.mixInMember(classMember);
+            } else {
+              tuple.mixedInMember = classMember;
+            }
+          }
+          for (ClassMember classMember in memberBuilder.localSetters) {
+            if (classMember.isAbstract) {
+              hasInterfaces = true;
+            }
+            Tuple? tuple = memberMap[classMember.name];
+            if (tuple == null) {
+              memberMap[classMember.name] = new Tuple.mixInSetter(classMember);
+            } else {
+              tuple.mixedInSetter = classMember;
+            }
+          }
+        }
+      }
+    }
+
+    void extend(Map<Name, ClassMember>? superClassMembers) {
+      if (superClassMembers == null) return;
+      for (MapEntry<Name, ClassMember> entry in superClassMembers.entries) {
+        Name name = entry.key;
+        ClassMember superClassMember = entry.value;
+        Tuple? tuple = memberMap[name];
+        if (tuple != null) {
+          if (superClassMember.forSetter) {
+            tuple.extendedSetter = superClassMember;
+          } else {
+            tuple.extendedMember = superClassMember;
+          }
+        } else {
+          if (superClassMember.forSetter) {
+            memberMap[name] = new Tuple.extendSetter(superClassMember);
+          } else {
+            memberMap[name] = new Tuple.extendMember(superClassMember);
+          }
+        }
+      }
+    }
+
+    void implement(Map<Name, ClassMember>? superInterfaceMembers) {
+      if (superInterfaceMembers == null) return;
+      for (MapEntry<Name, ClassMember> entry in superInterfaceMembers.entries) {
+        Name name = entry.key;
+        ClassMember superInterfaceMember = entry.value;
+        Tuple? tuple = memberMap[name];
+        if (tuple != null) {
+          if (superInterfaceMember.forSetter) {
+            tuple.addImplementedSetter(superInterfaceMember);
+          } else {
+            tuple.addImplementedMember(superInterfaceMember);
+          }
+        } else {
+          if (superInterfaceMember.forSetter) {
+            memberMap[superInterfaceMember.name] =
+                new Tuple.implementSetter(superInterfaceMember);
+          } else {
+            memberMap[superInterfaceMember.name] =
+                new Tuple.implementMember(superInterfaceMember);
+          }
+        }
+      }
+    }
+
+    if (supernode == null) {
+      // This should be Object.
+    } else {
+      extend(supernode.classMemberMap);
+      extend(supernode.classSetterMap);
+
+      if (supernode.interfaceMemberMap != null ||
+          supernode.interfaceSetterMap != null) {
+        hasInterfaces = true;
+      }
+
+      if (hasInterfaces) {
+        implement(supernode.interfaceMemberMap ?? supernode.classMemberMap);
+        implement(supernode.interfaceSetterMap ?? supernode.classSetterMap);
+      }
+
+      if (directInterfaceBuilders != null) {
+        for (int i = 0; i < directInterfaceBuilders.length; i++) {
+          ClassMembersNode? interfaceNode = _membersBuilder
+              .getNodeFromTypeBuilder(directInterfaceBuilders[i]);
+          if (interfaceNode != null) {
+            hasInterfaces = true;
+
+            implement(interfaceNode.interfaceMemberMap ??
+                interfaceNode.classMemberMap);
+            implement(interfaceNode.interfaceSetterMap ??
+                interfaceNode.classSetterMap);
+          }
+        }
+      }
+    }
+
+    /// Members (excluding setters) declared in [cls] or its superclasses. This
+    /// includes static methods of [cls], but not its superclasses.
+    Map<Name, ClassMember> classMemberMap = {};
+
+    /// Setters declared in [cls] or its superclasses. This includes static
+    /// setters of [cls], but not its superclasses.
+    Map<Name, ClassMember> classSetterMap = {};
+
+    /// Members (excluding setters) inherited from interfaces. This contains no
+    /// static members. If no interfaces are implemented by this class or its
+    /// superclasses this is identical to [classMemberMap] and we do not store
+    /// it in the [ClassHierarchyNode].
+    Map<Name, ClassMember>? interfaceMemberMap = {};
+
+    /// Setters inherited from interfaces. This contains no static setters. If
+    /// no interfaces are implemented by this class or its superclasses this is
+    /// identical to [classSetterMap] and we do not store it in the
+    /// [ClassHierarchyNode].
+    Map<Name, ClassMember>? interfaceSetterMap = {};
+
+    /// Map for members declared in this class to the members that they
+    /// override. This is used for checking valid overrides and to ensure that
+    /// override inference correctly propagates inferred types through the
+    /// class hierarchy.
+    Map<ClassMember, Set<ClassMember>> declaredOverridesMap = {};
+
+    /// In case this class is a mixin application, this maps members declared in
+    /// the mixin to the members that they override. This is used for checking
+    /// valid overrides but _not_ as for [declaredOverridesMap] for override
+    /// inference.
+    Map<ClassMember, Set<ClassMember>> mixinApplicationOverridesMap = {};
+
+    /// In case this class is concrete, this maps concrete members that are
+    /// inherited into this class to the members they should override to validly
+    /// implement the interface of this class.
+    Map<ClassMember, Set<ClassMember>> inheritedImplementsMap = {};
+
+    /// In case this class is concrete, this holds the interface members
+    /// without a corresponding class member. These are either reported as
+    /// missing implementations or trigger insertion of noSuchMethod forwarders.
+    List<ClassMember>? abstractMembers = [];
+
+    ClassHierarchyNodeDataForTesting? dataForTesting;
+    if (retainDataForTesting) {
+      dataForTesting = new ClassHierarchyNodeDataForTesting(
+          abstractMembers,
+          declaredOverridesMap,
+          mixinApplicationOverridesMap,
+          inheritedImplementsMap);
+    }
+
+    /// Registers that the current class has an interface member without a
+    /// corresponding class member.
+    ///
+    /// This is used to report missing implementation or, in the case the class
+    /// has a user defined concrete noSuchMethod, to insert noSuchMethod
+    /// forwarders. (Currently, insertion of forwarders is handled elsewhere.)
+    ///
+    /// For instance:
+    ///
+    ///    abstract class Interface {
+    ///      method();
+    ///    }
+    ///    class Class1 implements Interface {
+    ///      // Missing implementation for `Interface.method`.
+    ///    }
+    ///    class Class2 implements Interface {
+    ///      noSuchMethod(_) {}
+    ///      // A noSuchMethod forwarder is added for `Interface.method`.
+    ///    }
+    ///
+    void registerAbstractMember(ClassMember abstractMember) {
+      if (!abstractMember.isInternalImplementation) {
+        /// If `isInternalImplementation` is `true`, the member is synthesized
+        /// implementation that does not require implementation in other
+        /// classes.
+        ///
+        /// This is for instance used for late lowering where
+        ///
+        ///    class Interface {
+        ///      late int? field;
+        ///    }
+        ///    class Class implements Interface {
+        ///      int? field;
+        ///    }
+        ///
+        /// is encoded as
+        ///
+        ///    class Interface {
+        ///      bool _#field#isSet = false;
+        ///      int? _#field = null;
+        ///      int? get field => _#field#isSet ? _#field : throw ...;
+        ///      void set field(int? value) { ... }
+        ///    }
+        ///    class Class implements Interface {
+        ///      int? field;
+        ///    }
+        ///
+        /// and `Class` should not be required to implement
+        /// `Interface._#field#isSet` and `Interface._#field`.
+        abstractMembers.add(abstractMember);
+      }
+    }
+
+    /// Registers that [inheritedMember] should be checked to validly override
+    /// [overrides].
+    ///
+    /// This is needed in the case where a concrete member is inherited into
+    /// a concrete subclass. For instance:
+    ///
+    ///    class Super {
+    ///      void method() {}
+    ///    }
+    ///    abstract class Interface {
+    ///      void method();
+    ///    }
+    ///    class Class extends Super implements Interface {}
+    ///
+    /// Here `Super.method` must be checked to be a valid implementation for
+    /// `Interface.method` by being a valid override of it.
+    void registerInheritedImplements(
+        ClassMember inheritedMember, Set<ClassMember> overrides,
+        {required ClassMember aliasForTesting}) {
+      if (classBuilder is SourceClassBuilder) {
+        assert(
+            inheritedMember.classBuilder != classBuilder,
+            "Only inherited members can implement by inheritance: "
+            "${inheritedMember}");
+        inheritedImplementsMap[inheritedMember] = overrides;
+        // ignore: unnecessary_null_comparison
+        if (dataForTesting != null && aliasForTesting != null) {
+          dataForTesting.aliasMap[aliasForTesting] = inheritedMember;
+        }
+      }
+    }
+
+    /// Returns `true` if the current class is from an opt-out library and
+    /// [classMember] is from an opt-in library.
+    ///
+    /// In this case a member signature needs to be inserted to show the
+    /// legacy erased type of the interface member. For instance:
+    ///
+    ///    // Opt-in library:
+    ///    class Super {
+    ///      int? method(int i) {}
+    ///    }
+    ///    // Opt-out library:
+    ///    class Class extends Super {
+    ///      // A member signature is inserted:
+    ///      // int* method(int* i);
+    ///    }
+    ///
+    bool needsMemberSignatureFor(ClassMember classMember) {
+      return !classBuilder.library.isNonNullableByDefault &&
+          classMember.classBuilder.library.isNonNullableByDefault;
+    }
+
+    memberMap.forEach((Name name, Tuple tuple) {
+      /// The computation starts by sanitizing the members. Conflicts between
+      /// methods and properties (getters/setters) or between static and
+      /// instance members are reported. Conflicting members and members
+      /// overridden by duplicates are removed.
+      ///
+      /// For this [definingGetable] and [definingSetable] hold the first member
+      /// of its kind found among declared, mixed in, extended and implemented
+      /// members.
+      ///
+      /// Conflicts between [definingGetable] and [definingSetable] are reported
+      /// afterwards.
+
+      ClassMember? definingGetable;
+      ClassMember? definingSetable;
+
+      ClassMember? declaredGetable = tuple.declaredMember;
+      if (declaredGetable != null) {
+        /// class Class {
+        ///   method() {}
+        /// }
+        definingGetable = declaredGetable;
+      }
+      ClassMember? declaredSetable = tuple.declaredSetter;
+      if (declaredSetable != null) {
+        /// class Class {
+        ///   set setter(value) {}
+        /// }
+        definingSetable = declaredSetable;
+      }
+
+      ClassMember? mixedInGetable;
+      ClassMember? tupleMixedInMember = tuple.mixedInMember;
+      if (tupleMixedInMember != null &&
+          !tupleMixedInMember.isStatic &&
+          !tupleMixedInMember.isDuplicate &&
+          !tupleMixedInMember.isSynthesized) {
+        /// We treat
+        ///
+        ///   opt-in:
+        ///   class Interface {
+        ///     method3() {}
+        ///   }
+        ///   opt-out:
+        ///   class Mixin implements Interface {
+        ///     static method1() {}
+        ///     method2() {}
+        ///     method2() {}
+        ///     /*member-signature*/ method3() {}
+        ///   }
+        ///   class Class with Mixin {}
+        ///
+        /// as
+        ///
+        ///   class Mixin {}
+        ///   class Class with Mixin {}
+        ///
+        /// Note that skipped synthetic getable 'method3' is still included
+        /// in the implemented getables, but its type will not define the type
+        /// when mixed in. For instance
+        ///
+        ///   opt-in:
+        ///   abstract class Interface {
+        ///     num get getter;
+        ///   }
+        ///   opt-out:
+        ///   abstract class Super {
+        ///     int get getter;
+        ///   }
+        ///   abstract class Mixin implements Interface {
+        ///     /*member-signature*/ num get getter;
+        ///   }
+        ///   abstract class Class extends Super with Mixin {}
+        ///
+        /// Here the type of `Class.getter` should not be defined from the
+        /// synthetic member signature `Mixin.getter` but as a combined member
+        /// signature of `Super.getter` and `Mixin.getter`, resulting in type
+        /// `int` instead of `num`.
+        if (definingGetable == null) {
+          /// class Mixin {
+          ///   method() {}
+          /// }
+          /// class Class with Mixin {}
+          definingGetable = mixedInGetable = tupleMixedInMember;
+        } else if (!definingGetable.isDuplicate) {
+          // This case is currently unreachable from source code since classes
+          // cannot both declare and mix in members. From dill, this can occur
+          // but should not conflicting members.
+          //
+          // The case is handled for consistency.
+          if (definingGetable.isStatic ||
+              definingGetable.isProperty != tupleMixedInMember.isProperty) {
+            reportInheritanceConflict(definingGetable, tupleMixedInMember);
+          } else {
+            mixedInGetable = tupleMixedInMember;
+          }
+        }
+      }
+      ClassMember? mixedInSetable;
+      ClassMember? tupleMixedInSetter = tuple.mixedInSetter;
+      if (tupleMixedInSetter != null &&
+          !tupleMixedInSetter.isStatic &&
+          !tupleMixedInSetter.isDuplicate &&
+          !tupleMixedInSetter.isSynthesized) {
+        /// We treat
+        ///
+        ///   class Mixin {
+        ///     static set setter1(value) {}
+        ///     set setter2(value) {}
+        ///     set setter2(value) {}
+        ///     /*member-signature*/ setter3() {}
+        ///   }
+        ///   class Class with Mixin {}
+        ///
+        /// as
+        ///
+        ///   class Mixin {}
+        ///   class Class with Mixin {}
+        ///
+        /// Note that skipped synthetic setable 'setter3' is still included
+        /// in the implemented setables, but its type will not define the type
+        /// when mixed in. For instance
+        ///
+        ///   opt-in:
+        ///   abstract class Interface {
+        ///     void set setter(int value);
+        ///   }
+        ///   opt-out:
+        ///   abstract class Super {
+        ///     void set setter(num value);
+        ///   }
+        ///   abstract class Mixin implements Interface {
+        ///     /*member-signature*/ num get getter;
+        ///   }
+        ///   abstract class Class extends Super with Mixin {}
+        ///
+        /// Here the type of `Class.setter` should not be defined from the
+        /// synthetic member signature `Mixin.setter` but as a combined member
+        /// signature of `Super.setter` and `Mixin.setter`, resulting in type
+        /// `num` instead of `int`.
+        if (definingSetable == null) {
+          /// class Mixin {
+          ///   set setter(value) {}
+          /// }
+          /// class Class with Mixin {}
+          definingSetable = mixedInSetable = tupleMixedInSetter;
+        } else if (!definingSetable.isDuplicate) {
+          if (definingSetable.isStatic ||
+              definingSetable.isProperty != tupleMixedInSetter.isProperty) {
+            reportInheritanceConflict(definingSetable, tupleMixedInSetter);
+          } else {
+            mixedInSetable = tupleMixedInSetter;
+          }
+        }
+      }
+
+      ClassMember? extendedGetable;
+      ClassMember? tupleExtendedMember = tuple.extendedMember;
+      if (tupleExtendedMember != null &&
+          !tupleExtendedMember.isStatic &&
+          !tupleExtendedMember.isDuplicate) {
+        /// We treat
+        ///
+        ///   class Super {
+        ///     static method1() {}
+        ///     method2() {}
+        ///     method2() {}
+        ///   }
+        ///   class Class extends Super {}
+        ///
+        /// as
+        ///
+        ///   class Super {}
+        ///   class Class extends Super {}
+        ///
+        if (definingGetable == null) {
+          /// class Super {
+          ///   method() {}
+          /// }
+          /// class Class extends Super {}
+          definingGetable = extendedGetable = tupleExtendedMember;
+        } else if (!definingGetable.isDuplicate) {
+          if (definingGetable.isStatic ||
+              definingGetable.isProperty != tupleExtendedMember.isProperty) {
+            ///   class Super {
+            ///     method() {}
+            ///   }
+            ///   class Class extends Super {
+            ///     static method() {}
+            ///   }
+            ///
+            /// or
+            ///
+            ///   class Super {
+            ///     method() {}
+            ///   }
+            ///   class Class extends Super {
+            ///     get getter => 0;
+            ///   }
+            reportInheritanceConflict(definingGetable, tupleExtendedMember);
+          } else {
+            extendedGetable = tupleExtendedMember;
+          }
+        }
+      }
+      ClassMember? extendedSetable;
+      ClassMember? tupleExtendedSetter = tuple.extendedSetter;
+      if (tupleExtendedSetter != null &&
+          !tupleExtendedSetter.isStatic &&
+          !tupleExtendedSetter.isDuplicate) {
+        /// We treat
+        ///
+        ///   class Super {
+        ///     static set setter1(value) {}
+        ///     set setter2(value) {}
+        ///     set setter2(value) {}
+        ///   }
+        ///   class Class extends Super {}
+        ///
+        /// as
+        ///
+        ///   class Super {}
+        ///   class Class extends Super {}
+        ///
+        if (definingSetable == null) {
+          /// class Super {
+          ///   set setter(value) {}
+          /// }
+          /// class Class extends Super {}
+          definingSetable = extendedSetable = tupleExtendedSetter;
+        } else if (!definingSetable.isDuplicate) {
+          if (definingSetable.isStatic ||
+              definingSetable.isProperty != tupleExtendedSetter.isProperty) {
+            reportInheritanceConflict(definingSetable, tupleExtendedSetter);
+          } else {
+            extendedSetable = tupleExtendedSetter;
+          }
+        }
+      }
+
+      // TODO(johnniwinther): Remove extended and mixed in members/setters
+      // from implemented members/setters. Mixin applications always implement
+      // the mixin class leading to unnecessary interface members.
+      List<ClassMember>? implementedGetables;
+      List<ClassMember>? tupleImplementedMembers = tuple.implementedMembers;
+      if (tupleImplementedMembers != null &&
+          // Skip implemented members if we already have a duplicate.
+          !(definingGetable != null && definingGetable.isDuplicate)) {
+        for (int i = 0; i < tupleImplementedMembers.length; i++) {
+          ClassMember? implementedGetable = tupleImplementedMembers[i];
+          if (implementedGetable.isStatic || implementedGetable.isDuplicate) {
+            /// We treat
+            ///
+            ///   class Interface {
+            ///     static method1() {}
+            ///     method2() {}
+            ///     method2() {}
+            ///   }
+            ///   class Class implements Interface {}
+            ///
+            /// as
+            ///
+            ///   class Interface {}
+            ///   class Class implements Interface {}
+            ///
+            implementedGetable = null;
+          } else {
+            if (definingGetable == null) {
+              /// class Interface {
+              ///   method() {}
+              /// }
+              /// class Class implements Interface {}
+              definingGetable = implementedGetable;
+            } else if (definingGetable.isStatic ||
+                definingGetable.isProperty != implementedGetable.isProperty) {
+              ///   class Interface {
+              ///     method() {}
+              ///   }
+              ///   class Class implements Interface {
+              ///     static method() {}
+              ///   }
+              ///
+              /// or
+              ///
+              ///   class Interface {
+              ///     method() {}
+              ///   }
+              ///   class Class implements Interface {
+              ///     get getter => 0;
+              ///   }
+              reportInheritanceConflict(definingGetable, implementedGetable);
+              implementedGetable = null;
+            }
+          }
+          if (implementedGetable == null) {
+            // On the first skipped member we add all previous.
+            implementedGetables ??= tupleImplementedMembers.take(i).toList();
+          } else if (implementedGetables != null) {
+            // If already skipping members we add [implementedGetable]
+            // explicitly.
+            implementedGetables.add(implementedGetable);
+          }
+        }
+        if (implementedGetables == null) {
+          // No members were skipped so we use the full list.
+          implementedGetables = tupleImplementedMembers;
+        } else if (implementedGetables.isEmpty) {
+          // No members were included.
+          implementedGetables = null;
+        }
+      }
+
+      List<ClassMember>? implementedSetables;
+      List<ClassMember>? tupleImplementedSetters = tuple.implementedSetters;
+      if (tupleImplementedSetters != null &&
+          // Skip implemented setters if we already have a duplicate.
+          !(definingSetable != null && definingSetable.isDuplicate)) {
+        for (int i = 0; i < tupleImplementedSetters.length; i++) {
+          ClassMember? implementedSetable = tupleImplementedSetters[i];
+          if (implementedSetable.isStatic || implementedSetable.isDuplicate) {
+            /// We treat
+            ///
+            ///   class Interface {
+            ///     static set setter1(value) {}
+            ///     set setter2(value) {}
+            ///     set setter2(value) {}
+            ///   }
+            ///   class Class implements Interface {}
+            ///
+            /// as
+            ///
+            ///   class Interface {}
+            ///   class Class implements Interface {}
+            ///
+            implementedSetable = null;
+          } else {
+            if (definingSetable == null) {
+              /// class Interface {
+              ///   set setter(value) {}
+              /// }
+              /// class Class implements Interface {}
+              definingSetable = implementedSetable;
+            } else if (definingSetable.isStatic ||
+                definingSetable.isProperty != implementedSetable.isProperty) {
+              /// class Interface {
+              ///   set setter(value) {}
+              /// }
+              /// class Class implements Interface {
+              ///   static set setter(value) {}
+              /// }
+              reportInheritanceConflict(definingSetable, implementedSetable);
+              implementedSetable = null;
+            }
+          }
+          if (implementedSetable == null) {
+            // On the first skipped setter we add all previous.
+            implementedSetables ??= tupleImplementedSetters.take(i).toList();
+          } else if (implementedSetables != null) {
+            // If already skipping setters we add [implementedSetable]
+            // explicitly.
+            implementedSetables.add(implementedSetable);
+          }
+        }
+        if (implementedSetables == null) {
+          // No setters were skipped so we use the full list.
+          implementedSetables = tupleImplementedSetters;
+        } else if (implementedSetables.isEmpty) {
+          // No setters were included.
+          implementedSetables = null;
+        }
+      }
+
+      if (definingGetable != null && definingSetable != null) {
+        if (definingGetable.isStatic != definingSetable.isStatic ||
+            definingGetable.isProperty != definingSetable.isProperty) {
+          reportInheritanceConflict(definingGetable, definingSetable);
+          // TODO(johnniwinther): Should we remove [definingSetable]? If we
+          // leave it in this conflict will also be reported in subclasses. If
+          // we remove it, any write to the setable will be unresolved.
+        }
+      }
+
+      // TODO(johnniwinther): Handle declared members together with mixed in
+      // members. This should only occur from .dill, though.
+      if (mixedInGetable != null) {
+        declaredGetable = null;
+      }
+      if (mixedInSetable != null) {
+        declaredSetable = null;
+      }
+
+      /// Set to `true` if declared members have been registered in
+      /// [registerDeclaredOverride] or [registerMixedInOverride].
+      bool hasDeclaredMembers = false;
+
+      /// Declared methods, getters and setters registered in
+      /// [registerDeclaredOverride].
+      ClassMember? declaredMethod;
+      List<ClassMember>? declaredProperties;
+
+      /// Declared methods, getters and setters registered in
+      /// [registerDeclaredOverride].
+      ClassMember? mixedInMethod;
+      List<ClassMember>? mixedInProperties;
+
+      /// Registers that [declaredMember] overrides extended and implemented
+      /// members.
+      ///
+      /// Getters and setters share overridden members so the registration
+      /// of override relations is performed after the interface members have
+      /// been computed.
+      ///
+      /// Declared members must be checked for valid override of the overridden
+      /// members _and_ must register an override dependency with the overridden
+      /// members so that override inference can propagate inferred types
+      /// correctly. For instance:
+      ///
+      ///    class Super {
+      ///      int get property => 42;
+      ///    }
+      ///    class Class extends Super {
+      ///      void set property(value) {}
+      ///    }
+      ///
+      /// Here the parameter type of the setter `Class.property` must be
+      /// inferred from the type of the getter `Super.property`.
+      void registerDeclaredOverride(ClassMember declaredMember,
+          {ClassMember? aliasForTesting}) {
+        if (classBuilder is SourceClassBuilder && !declaredMember.isStatic) {
+          assert(
+              declaredMember.isSourceDeclaration &&
+                  declaredMember.classBuilder == classBuilder,
+              "Only declared members can override: ${declaredMember}");
+          hasDeclaredMembers = true;
+          if (declaredMember.isProperty) {
+            declaredProperties ??= [];
+            declaredProperties!.add(declaredMember);
+          } else {
+            assert(
+                declaredMethod == null,
+                "Multiple methods unexpectedly declared: "
+                "${declaredMethod} and ${declaredMember}.");
+            declaredMethod = declaredMember;
+          }
+          if (dataForTesting != null && aliasForTesting != null) {
+            dataForTesting.aliasMap[aliasForTesting] = declaredMember;
+          }
+        }
+      }
+
+      /// Registers that [mixedMember] overrides extended and implemented
+      /// members through application.
+      ///
+      /// Getters and setters share overridden members so the registration
+      /// of override relations in performed after the interface members have
+      /// been computed.
+      ///
+      /// Declared mixed in members must be checked for valid override of the
+      /// overridden members but _not_ register an override dependency with the
+      /// overridden members. This is in contrast to declared members. For
+      /// instance:
+      ///
+      ///    class Super {
+      ///      int get property => 42;
+      ///    }
+      ///    class Mixin {
+      ///      void set property(value) {}
+      ///    }
+      ///    class Class = Super with Mixin;
+      ///
+      /// Here the parameter type of the setter `Mixin.property` must _not_ be
+      /// inferred from the type of the getter `Super.property`, but should
+      /// instead default to `dynamic`.
+      void registerMixedInOverride(ClassMember mixedInMember,
+          {ClassMember? aliasForTesting}) {
+        assert(mixedInMember.classBuilder != classBuilder,
+            "Only mixin members can override by application: ${mixedInMember}");
+        if (classBuilder is SourceClassBuilder) {
+          hasDeclaredMembers = true;
+          if (mixedInMember.isProperty) {
+            mixedInProperties ??= [];
+            mixedInProperties!.add(mixedInMember);
+          } else {
+            assert(
+                mixedInMethod == null,
+                "Multiple methods unexpectedly declared in mixin: "
+                "${mixedInMethod} and ${mixedInMember}.");
+            mixedInMethod = mixedInMember;
+          }
+          if (dataForTesting != null && aliasForTesting != null) {
+            dataForTesting.aliasMap[aliasForTesting] = mixedInMember;
+          }
+        }
+      }
+
+      /// Computes the class and interface members for a method, getter, or
+      /// setter in the current [tuple].
+      ///
+      /// [definingMember] is the member which defines whether the computation
+      /// is for a method, a getter or a setter.
+      /// [declaredMember] is the member declared in the current class, if any.
+      /// [mixedInMember] is the member declared in a mixin that is mixed into
+      /// the current current class, if any.
+      /// [extendedMember] is the member inherited from the super class.
+      /// [implementedMembers] are the members inherited from the super
+      /// interfaces, if none this is `null`.
+      ///
+      /// The computed class and interface members are added to [classMemberMap]
+      /// and [interfaceMemberMap], respectively.
+      ClassMember? computeMembers(
+          {required ClassMember definingMember,
+          required ClassMember? declaredMember,
+          required ClassMember? mixedInMember,
+          required ClassMember? extendedMember,
+          required List<ClassMember>? implementedMembers,
+          required Map<Name, ClassMember> classMemberMap,
+          required Map<Name, ClassMember>? interfaceMemberMap}) {
+        ClassMember? classMember;
+        ClassMember? interfaceMember;
+
+        if (mixedInMember != null) {
+          if (mixedInMember.isAbstract) {
+            ///    class Mixin {
+            ///      method();
+            ///    }
+            ///    class Class = Object with Mixin;
+
+            /// Interface members from the extended, mixed in, and implemented
+            /// members define the combined member signature.
+            Set<ClassMember> interfaceMembers = {};
+
+            if (extendedMember != null) {
+              ///    class Super {
+              ///      method() {}
+              ///    }
+              ///    class Mixin {
+              ///      method();
+              ///    }
+              ///    class Class = Super with Mixin;
+              interfaceMembers.add(extendedMember.interfaceMember);
+            }
+
+            interfaceMembers.add(mixedInMember);
+
+            if (implementedMembers != null) {
+              ///    class Interface {
+              ///      method() {}
+              ///    }
+              ///    class Mixin {
+              ///      method();
+              ///    }
+              ///    class Class = Object with Mixin implements Interface;
+              interfaceMembers.addAll(implementedMembers);
+            }
+
+            /// We always create a synthesized interface member, even in the
+            /// case of [interfaceMembers] being a singleton, to insert the
+            /// abstract mixin stub.
+            interfaceMember = new SynthesizedInterfaceMember(
+                classBuilder, name, interfaceMembers.toList(),
+                superClassMember: extendedMember,
+                // [definingMember] and [mixedInMember] are always the same
+                // here. Use the latter here and the former below to show the
+                // the member is canonical _because_ its the mixed in member and
+                // it defines the isProperty/forSetter properties _because_ it
+                // is the defining member.
+                canonicalMember: mixedInMember,
+                mixedInMember: mixedInMember,
+                isProperty: definingMember.isProperty,
+                forSetter: definingMember.forSetter,
+                shouldModifyKernel: shouldModifyKernel);
+            _membersBuilder.registerMemberComputation(interfaceMember);
+
+            if (extendedMember != null) {
+              ///    class Super {
+              ///      method() {}
+              ///    }
+              ///    class Mixin {
+              ///      method();
+              ///    }
+              ///    class Class = Super with Mixin;
+              ///
+              /// The concrete extended member is the class member but might
+              /// be overwritten by a concrete forwarding stub:
+              ///
+              ///    class Super {
+              ///      method(int i) {}
+              ///    }
+              ///    class Interface {
+              ///      method(covariant int i) {}
+              ///    }
+              ///    class Mixin {
+              ///      method(int i);
+              ///    }
+              ///    // A concrete forwarding stub
+              ///    //   method(covariant int i) => super.method(i);
+              ///    // will be inserted.
+              ///    class Class = Super with Mixin implements Interface;
+              ///
+              classMember = new InheritedClassMemberImplementsInterface(
+                  classBuilder, name,
+                  inheritedClassMember: extendedMember,
+                  implementedInterfaceMember: interfaceMember,
+                  forSetter: definingMember.forSetter,
+                  isProperty: definingMember.isProperty);
+              _membersBuilder.registerMemberComputation(classMember);
+              if (!classBuilder.isAbstract) {
+                registerInheritedImplements(extendedMember, {interfaceMember},
+                    aliasForTesting: classMember);
+              }
+            } else if (!classBuilder.isAbstract) {
+              ///    class Mixin {
+              ///      method(); // Missing implementation.
+              ///    }
+              ///    class Class = Object with Mixin;
+              registerAbstractMember(interfaceMember);
+            }
+
+            assert(!mixedInMember.isSynthesized);
+            if (!mixedInMember.isSynthesized) {
+              /// Members declared in the mixin must override extended and
+              /// implemented members.
+              ///
+              /// When loading from .dill the mixed in member might be
+              /// synthesized, for instance a member signature or forwarding
+              /// stub, and this should not be checked to override the extended
+              /// and implemented members:
+              ///
+              ///    // Opt-out library, from source:
+              ///    class Mixin {}
+              ///    // Opt-out library, from .dill:
+              ///    class Mixin {
+              ///      ...
+              ///      String* toString(); // member signature
+              ///    }
+              ///    // Opt-out library, from source:
+              ///    class Class = Object with Mixin;
+              ///    // Mixin.toString should not be checked to override
+              ///    // Object.toString.
+              ///
+              registerMixedInOverride(mixedInMember,
+                  aliasForTesting: interfaceMember);
+            }
+          } else {
+            assert(!mixedInMember.isAbstract);
+
+            ///    class Mixin {
+            ///      method() {}
+            ///    }
+            ///    class Class = Object with Mixin;
+            ///
+
+            /// Interface members from the extended, mixed in, and implemented
+            /// members define the combined member signature.
+            Set<ClassMember> interfaceMembers = {};
+
+            if (extendedMember != null) {
+              ///    class Super {
+              ///      method() {}
+              ///    }
+              ///    class Mixin {
+              ///      method() {}
+              ///    }
+              ///    class Class = Super with Mixin;
+              interfaceMembers.add(extendedMember.interfaceMember);
+            }
+
+            interfaceMembers.add(mixedInMember);
+
+            if (implementedMembers != null) {
+              ///    class Interface {
+              ///      method() {}
+              ///    }
+              ///    class Mixin {
+              ///      method() {}
+              ///    }
+              ///    class Class = Object with Mixin implements Interface;
+              interfaceMembers.addAll(implementedMembers);
+            }
+
+            /// We always create a synthesized interface member, even in the
+            /// case of [interfaceMembers] being a singleton, to insert the
+            /// concrete mixin stub.
+            interfaceMember = new SynthesizedInterfaceMember(
+                classBuilder, name, interfaceMembers.toList(),
+                superClassMember: mixedInMember,
+                // [definingMember] and [mixedInMember] are always the same
+                // here. Use the latter here and the former below to show the
+                // the member is canonical _because_ its the mixed in member and
+                // it defines the isProperty/forSetter properties _because_ it
+                // is the defining member.
+                canonicalMember: mixedInMember,
+                mixedInMember: mixedInMember,
+                isProperty: definingMember.isProperty,
+                forSetter: definingMember.forSetter,
+                shouldModifyKernel: shouldModifyKernel);
+            _membersBuilder.registerMemberComputation(interfaceMember);
+
+            /// The concrete mixed in member is the class member but will
+            /// be overwritten by a concrete mixin stub:
+            ///
+            ///    class Mixin {
+            ///       method() {}
+            ///    }
+            ///    // A concrete mixin stub
+            ///    //   method() => super.method();
+            ///    // will be inserted.
+            ///    class Class = Object with Mixin;
+            ///
+            classMember = new InheritedClassMemberImplementsInterface(
+                classBuilder, name,
+                inheritedClassMember: mixedInMember,
+                implementedInterfaceMember: interfaceMember,
+                forSetter: definingMember.forSetter,
+                isProperty: definingMember.isProperty);
+            _membersBuilder.registerMemberComputation(classMember);
+
+            if (!classBuilder.isAbstract) {
+              ///    class Interface {
+              ///      method() {}
+              ///    }
+              ///    class Mixin {
+              ///      method() {}
+              ///    }
+              ///    class Class = Object with Mixin;
+              ///
+              /// [mixinMember] must implemented interface member.
+              registerInheritedImplements(mixedInMember, {interfaceMember},
+                  aliasForTesting: classMember);
+            }
+            assert(!mixedInMember.isSynthesized);
+            if (!mixedInMember.isSynthesized) {
+              /// Members declared in the mixin must override extended and
+              /// implemented members.
+              ///
+              /// When loading from .dill the mixed in member might be
+              /// synthesized, for instance a member signature or forwarding
+              /// stub, and this should not be checked to override the extended
+              /// and implemented members.
+              ///
+              /// These synthesized mixed in members should always be abstract
+              /// and therefore not be handled here, but we handled them here
+              /// for consistency.
+              registerMixedInOverride(mixedInMember);
+            }
+          }
+        } else if (declaredMember != null) {
+          if (declaredMember.isAbstract) {
+            ///    class Class {
+            ///      method();
+            ///    }
+            interfaceMember = declaredMember;
+
+            /// Interface members from the declared, extended, and implemented
+            /// members define the combined member signature.
+            Set<ClassMember> interfaceMembers = {};
+
+            if (extendedMember != null) {
+              ///    class Super {
+              ///      method() {}
+              ///    }
+              ///    class Class extends Super {
+              ///      method();
+              ///    }
+              interfaceMembers.add(extendedMember);
+            }
+
+            interfaceMembers.add(declaredMember);
+
+            if (implementedMembers != null) {
+              ///    class Interface {
+              ///      method() {}
+              ///    }
+              ///    class Class implements Interface {
+              ///      method();
+              ///    }
+              interfaceMembers.addAll(implementedMembers);
+            }
+
+            /// If only one member defines the interface member there is no
+            /// need for a synthesized interface member, since its result will
+            /// simply be that one member.
+            if (interfaceMembers.length > 1) {
+              ///    class Super {
+              ///      method() {}
+              ///    }
+              ///    class Interface {
+              ///      method() {}
+              ///    }
+              ///    class Class extends Super implements Interface {
+              ///      method();
+              ///    }
+              interfaceMember = new SynthesizedInterfaceMember(
+                  classBuilder, name, interfaceMembers.toList(),
+                  superClassMember: extendedMember,
+                  // [definingMember] and [declaredMember] are always the same
+                  // here. Use the latter here and the former below to show the
+                  // the member is canonical _because_ its the declared member
+                  // and it defines the isProperty/forSetter properties
+                  // _because_ it is the defining member.
+                  canonicalMember: declaredMember,
+                  isProperty: definingMember.isProperty,
+                  forSetter: definingMember.forSetter,
+                  shouldModifyKernel: shouldModifyKernel);
+              _membersBuilder.registerMemberComputation(interfaceMember);
+            }
+
+            if (extendedMember != null) {
+              ///    class Super {
+              ///      method() {}
+              ///    }
+              ///    class Class extends Super {
+              ///      method();
+              ///    }
+              ///
+              /// The concrete extended member is the class member but might
+              /// be overwritten by a concrete forwarding stub:
+              ///
+              ///    class Super {
+              ///      method(int i) {}
+              ///    }
+              ///    class Interface {
+              ///      method(covariant int i) {}
+              ///    }
+              ///    class Class extends Super implements Interface {
+              ///      // This will be turned into the concrete forwarding stub
+              ///      //    method(covariant int i) => super.method(i);
+              ///      method(int i);
+              ///    }
+              ///
+              classMember = new InheritedClassMemberImplementsInterface(
+                  classBuilder, name,
+                  inheritedClassMember: extendedMember,
+                  implementedInterfaceMember: interfaceMember,
+                  forSetter: definingMember.forSetter,
+                  isProperty: definingMember.isProperty);
+              _membersBuilder.registerMemberComputation(classMember);
+
+              if (!classBuilder.isAbstract) {
+                ///    class Super {
+                ///      method() {}
+                ///    }
+                ///    class Class extends Super {
+                ///      method();
+                ///    }
+                ///
+                /// [extendedMember] must implemented interface member.
+                registerInheritedImplements(extendedMember, {interfaceMember},
+                    aliasForTesting: classMember);
+              }
+            } else if (!classBuilder.isAbstract) {
+              ///    class Class {
+              ///      method(); // Missing implementation.
+              ///    }
+              registerAbstractMember(declaredMember);
+            }
+
+            /// The declared member must override extended and implemented
+            /// members.
+            registerDeclaredOverride(declaredMember,
+                aliasForTesting: interfaceMember);
+          } else {
+            assert(!declaredMember.isAbstract);
+
+            ///    class Class {
+            ///      method() {}
+            ///    }
+            classMember = declaredMember;
+
+            /// The declared member must override extended and implemented
+            /// members.
+            registerDeclaredOverride(declaredMember);
+          }
+        } else if (extendedMember != null) {
+          ///    class Super {
+          ///      method() {}
+          ///    }
+          ///    class Class extends Super {}
+          assert(!extendedMember.isAbstract,
+              "Abstract extended member: ${extendedMember}");
+
+          classMember = extendedMember;
+
+          if (implementedMembers != null) {
+            ///    class Super {
+            ///      method() {}
+            ///    }
+            ///    class Interface {
+            ///      method() {}
+            ///    }
+            ///    class Class extends Super implements Interface {}
+            ClassMember extendedInterfaceMember =
+                extendedMember.interfaceMember;
+
+            /// Interface members from the extended and implemented
+            /// members define the combined member signature.
+            Set<ClassMember> interfaceMembers = {extendedInterfaceMember};
+
+            // TODO(johnniwinther): The extended member might be included in
+            // a synthesized implemented member. For instance:
+            //
+            //    class Super {
+            //      void method() {}
+            //    }
+            //    class Interface {
+            //      void method() {}
+            //    }
+            //    abstract class Class extends Super implements Interface {
+            //      // Synthesized interface member of
+            //      //   {Super.method, Interface.method}
+            //    }
+            //    class Sub extends Class {
+            //      // Super.method implements Class.method =
+            //      //   {Super.method, Interface.method}
+            //      // Synthesized interface member of
+            //      //   {Super.method, Class.method}
+            //    }
+            //
+            // Maybe we should recognize this.
+            interfaceMembers.addAll(implementedMembers);
+
+            /// Normally, if only one member defines the interface member there
+            /// is no need for a synthesized interface member, since its result
+            /// will simply be that one member, but if the extended member is
+            /// from an opt-in library and the current class is from an opt-out
+            /// library we need to create a member signature:
+            ///
+            ///    // Opt-in:
+            ///    class Super {
+            ///      int? method() => null;
+            ///    }
+            ///    class Interface implements Super {}
+            ///    // Opt-out:
+            ///    class Class extends Super implements Interface {
+            ///      // Member signature added:
+            ///      int* method();
+            ///    }
+            ///
+            if (interfaceMembers.length == 1 &&
+                !needsMemberSignatureFor(extendedInterfaceMember)) {
+              ///    class Super {
+              ///      method() {}
+              ///    }
+              ///    class Interface implements Super {}
+              ///    class Class extends Super implements Interface {}
+              interfaceMember = interfaceMembers.first;
+            } else {
+              ///    class Super {
+              ///      method() {}
+              ///    }
+              ///    class Interface {
+              ///      method() {}
+              ///    }
+              ///    class Class extends Super implements Interface {}
+              interfaceMember = new SynthesizedInterfaceMember(
+                  classBuilder, name, interfaceMembers.toList(),
+                  superClassMember: extendedMember,
+                  isProperty: definingMember.isProperty,
+                  forSetter: definingMember.forSetter,
+                  shouldModifyKernel: shouldModifyKernel);
+              _membersBuilder.registerMemberComputation(interfaceMember);
+            }
+            if (interfaceMember == classMember) {
+              ///    class Super {
+              ///      method() {}
+              ///    }
+              ///    class Interface implements Super {}
+              ///    class Class extends Super implements Interface {}
+              ///
+              /// We keep track of whether a class needs interfaces, that is,
+              /// whether is has any members that have an interface member
+              /// different from its corresponding class member, so we set
+              /// [interfaceMember] to `null` so show that the interface member
+              /// is not needed.
+              interfaceMember = null;
+            } else {
+              ///    class Super {
+              ///      method() {}
+              ///    }
+              ///    class Interface {
+              ///      method() {}
+              ///    }
+              ///    class Class extends Super implements Interface {}
+              ///
+              /// The concrete extended member is the class member but might
+              /// be overwritten by a concrete forwarding stub:
+              ///
+              ///    class Super {
+              ///      method(int i) {}
+              ///    }
+              ///    class Interface {
+              ///      method(covariant int i) {}
+              ///    }
+              ///    class Class extends Super implements Interface {
+              ///      // A concrete forwarding stub will be created:
+              ///      //    method(covariant int i) => super.method(i);
+              ///    }
+              ///
+              classMember = new InheritedClassMemberImplementsInterface(
+                  classBuilder, name,
+                  inheritedClassMember: extendedMember,
+                  implementedInterfaceMember: interfaceMember,
+                  isProperty: definingMember.isProperty,
+                  forSetter: definingMember.forSetter);
+              _membersBuilder.registerMemberComputation(classMember);
+              if (!classBuilder.isAbstract) {
+                ///    class Super {
+                ///      method() {}
+                ///    }
+                ///    class Interface {
+                ///      method() {}
+                ///    }
+                ///    class Class extends Super implements Interface {}
+                registerInheritedImplements(extendedMember, {interfaceMember},
+                    aliasForTesting: classMember);
+              }
+            }
+          } else if (needsMemberSignatureFor(extendedMember)) {
+            ///    // Opt-in library:
+            ///    class Super {
+            ///      method() {}
+            ///    }
+            ///    // opt-out library:
+            ///    class Class extends Super {}
+            interfaceMember = new SynthesizedInterfaceMember(
+                classBuilder, name, [extendedMember],
+                superClassMember: extendedMember,
+                isProperty: definingMember.isProperty,
+                forSetter: definingMember.forSetter,
+                shouldModifyKernel: shouldModifyKernel);
+            _membersBuilder.registerMemberComputation(interfaceMember);
+
+            /// The concrete extended member is the class member and should
+            /// be able to be overwritten by a synthesized concrete member here,
+            /// but we handle the case for consistency.
+            classMember = new InheritedClassMemberImplementsInterface(
+                classBuilder, name,
+                inheritedClassMember: extendedMember,
+                implementedInterfaceMember: interfaceMember,
+                isProperty: definingMember.isProperty,
+                forSetter: definingMember.forSetter);
+            _membersBuilder.registerMemberComputation(classMember);
+          }
+        } else if (implementedMembers != null) {
+          ///    class Interface {
+          ///      method() {}
+          ///    }
+          ///    class Class implements Interface {}
+          Set<ClassMember> interfaceMembers = implementedMembers.toSet();
+          if (interfaceMembers.isNotEmpty) {
+            /// Normally, if only one member defines the interface member there
+            /// is no need for a synthesized interface member, since its result
+            /// will simply be that one member, but if the implemented member is
+            /// from an opt-in library and the current class is from an opt-out
+            /// library we need to create a member signature:
+            ///
+            ///    // Opt-in:
+            ///    class Interface {
+            ///      int? method() => null;
+            ///    }
+            ///    // Opt-out:
+            ///    class Class implements Interface {
+            ///      // Member signature added:
+            ///      int* method();
+            ///    }
+            ///
+            if (interfaceMembers.length == 1 &&
+                !needsMemberSignatureFor(interfaceMembers.first)) {
+              ///    class Interface {
+              ///      method() {}
+              ///    }
+              ///    class Class implements Interface {}
+              interfaceMember = interfaceMembers.first;
+            } else {
+              ///    class Interface1 {
+              ///      method() {}
+              ///    }
+              ///    class Interface2 {
+              ///      method() {}
+              ///    }
+              ///    class Class implements Interface1, Interface2 {}
+              interfaceMember = new SynthesizedInterfaceMember(
+                  classBuilder, name, interfaceMembers.toList(),
+                  isProperty: definingMember.isProperty,
+                  forSetter: definingMember.forSetter,
+                  shouldModifyKernel: shouldModifyKernel);
+              _membersBuilder.registerMemberComputation(interfaceMember);
+            }
+            if (!classBuilder.isAbstract) {
+              ///    class Interface {
+              ///      method() {}
+              ///    }
+              ///    class Class implements Interface {}
+              for (ClassMember abstractMember in interfaceMembers) {
+                registerAbstractMember(abstractMember);
+              }
+            }
+          }
+        }
+
+        if (interfaceMember != null) {
+          // We have an explicit interface.
+          hasInterfaces = true;
+        }
+        if (classMember != null) {
+          if (name == noSuchMethodName &&
+              !classMember.isObjectMember(objectClass)) {
+            hasNoSuchMethod = true;
+          }
+          classMemberMap[name] = classMember;
+          interfaceMember ??= classMember.interfaceMember;
+        }
+        if (interfaceMember != null) {
+          interfaceMemberMap![name] = interfaceMember;
+        }
+        return interfaceMember;
+      }
+
+      ClassMember? interfaceGetable;
+      if (definingGetable != null) {
+        interfaceGetable = computeMembers(
+            definingMember: definingGetable,
+            declaredMember: declaredGetable,
+            mixedInMember: mixedInGetable,
+            extendedMember: extendedGetable,
+            implementedMembers: implementedGetables,
+            classMemberMap: classMemberMap,
+            interfaceMemberMap: interfaceMemberMap);
+      }
+      ClassMember? interfaceSetable;
+      if (definingSetable != null) {
+        interfaceSetable = computeMembers(
+            definingMember: definingSetable,
+            declaredMember: declaredSetable,
+            mixedInMember: mixedInSetable,
+            extendedMember: extendedSetable,
+            implementedMembers: implementedSetables,
+            classMemberMap: classSetterMap,
+            interfaceMemberMap: interfaceSetterMap);
+      }
+      if (classBuilder is SourceClassBuilder) {
+        if (interfaceGetable != null &&
+            interfaceSetable != null &&
+            interfaceGetable.isProperty &&
+            interfaceSetable.isProperty &&
+            interfaceGetable.isStatic == interfaceSetable.isStatic &&
+            !interfaceGetable.isSameDeclaration(interfaceSetable)) {
+          /// We need to check that the getter type is a subtype of the setter
+          /// type. For instance
+          ///
+          ///    class Super {
+          ///       int get property1 => null;
+          ///       num get property2 => null;
+          ///    }
+          ///    class Mixin {
+          ///       void set property1(num value) {}
+          ///       void set property2(int value) {}
+          ///    }
+          ///    class Class = Super with Mixin;
+          ///
+          /// Here `Super.property1` and `Mixin.property1` form a valid getter/
+          /// setter pair in `Class` because the type of the getter
+          /// `Super.property1` is a subtype of the setter `Mixin.property1`.
+          ///
+          /// In contrast the pair `Super.property2` and `Mixin.property2` is
+          /// not a valid getter/setter in `Class` because the type of the getter
+          /// `Super.property2` is _not_ a subtype of the setter
+          /// `Mixin.property1`.
+          _membersBuilder.registerGetterSetterCheck(
+              classBuilder as SourceClassBuilder,
+              interfaceGetable,
+              interfaceSetable);
+        }
+      }
+      if (hasDeclaredMembers) {
+        Set<ClassMember> getableOverrides = {};
+        Set<ClassMember> setableOverrides = {};
+        if (extendedGetable != null) {
+          ///    (abstract) class Super {
+          ///      method() {}
+          ///      int get property => 0;
+          ///    }
+          ///    (abstract) class Class extends Super {
+          ///      method() {}
+          ///      set property(int value) {}
+          ///    }
+          getableOverrides.add(extendedGetable.interfaceMember);
+        }
+        if (extendedSetable != null) {
+          ///    (abstract) class Super {
+          ///      set setter(int value) {}
+          ///      set property(int value) {}
+          ///    }
+          ///    (abstract) class Class extends Super {
+          ///      set setter(int value) {}
+          ///      int get property => 0;
+          ///    }
+          setableOverrides.add(extendedSetable.interfaceMember);
+        }
+        if (implementedGetables != null) {
+          ///    (abstract) class Interface {
+          ///      method() {}
+          ///      int get property => 0;
+          ///    }
+          ///    (abstract) class Class implements Interface {
+          ///      method() {}
+          ///      set property(int value) {}
+          ///    }
+          getableOverrides.addAll(implementedGetables);
+        }
+        if (implementedSetables != null) {
+          ///    (abstract) class Interface {
+          ///      set setter(int value) {}
+          ///      set property(int value) {}
+          ///    }
+          ///    (abstract) class Class implements Interface {
+          ///      set setter(int value) {}
+          ///      int get property => 0;
+          ///    }
+          setableOverrides.addAll(implementedSetables);
+        }
+        if (getableOverrides.isNotEmpty || setableOverrides.isNotEmpty) {
+          if (declaredMethod != null && getableOverrides.isNotEmpty) {
+            ///    class Super {
+            ///      method() {}
+            ///    }
+            ///    class Class extends Super {
+            ///      method() {}
+            ///    }
+            declaredOverridesMap[declaredMethod!] = getableOverrides;
+          }
+          if (declaredProperties != null) {
+            Set<ClassMember> overrides;
+            if (declaredMethod != null) {
+              ///    class Super {
+              ///      set setter() {}
+              ///    }
+              ///    class Class extends Super {
+              ///      method() {}
+              ///    }
+              overrides = setableOverrides;
+            } else {
+              ///    class Super {
+              ///      get property => null
+              ///      void set property(value) {}
+              ///    }
+              ///    class Class extends Super {
+              ///      get property => null
+              ///      void set property(value) {}
+              ///    }
+              overrides = {...getableOverrides, ...setableOverrides};
+            }
+            if (overrides.isNotEmpty) {
+              for (ClassMember declaredMember in declaredProperties!) {
+                declaredOverridesMap[declaredMember] = overrides;
+              }
+            }
+          }
+          if (mixedInMethod != null && getableOverrides.isNotEmpty) {
+            ///    class Super {
+            ///      method() {}
+            ///    }
+            ///    class Mixin {
+            ///      method() {}
+            ///    }
+            ///    class Class = Super with Mixin;
+            mixinApplicationOverridesMap[mixedInMethod!] = getableOverrides;
+          }
+          if (mixedInProperties != null) {
+            Set<ClassMember> overrides;
+            if (mixedInMethod != null) {
+              ///    class Super {
+              ///      set setter() {}
+              ///    }
+              ///    class Mixin {
+              ///      method() {}
+              ///    }
+              ///    class Class = Super with Mixin;
+              overrides = setableOverrides;
+            } else {
+              ///    class Super {
+              ///      method() {}
+              ///    }
+              ///    class Mixin extends Super {
+              ///      method() {}
+              ///    }
+              overrides = {...getableOverrides, ...setableOverrides};
+            }
+            if (overrides.isNotEmpty) {
+              for (ClassMember mixedInMember in mixedInProperties!) {
+                mixinApplicationOverridesMap[mixedInMember] = overrides;
+              }
+            }
+          }
+        }
+      }
+    });
+
+    if (classBuilder is SourceClassBuilder) {
+      // TODO(johnniwinther): Avoid duplicate override check computations
+      //  between [declaredOverridesMap], [mixinApplicationOverridesMap] and
+      //  [inheritedImplementsMap].
+
+      // TODO(johnniwinther): Ensure that a class member is only checked to
+      // validly override another member once. Currently it can happen multiple
+      // times as an inherited implementation.
+
+      declaredOverridesMap.forEach(
+          (ClassMember classMember, Set<ClassMember> overriddenMembers) {
+        /// A declared member can inherit its type from the overridden members.
+        ///
+        /// We register this with the class member itself so the it can force
+        /// computation of type on the overridden members before determining its
+        /// own type.
+        ///
+        /// Member types can be queried at arbitrary points during top level
+        /// inference so we need to ensure that types are computed in dependency
+        /// order.
+        classMember.registerOverrideDependency(overriddenMembers);
+
+        /// Not all member type are queried during top level inference so we
+        /// register delayed computation to ensure that all types have been
+        /// computed before override checks are performed.
+        DelayedTypeComputation computation =
+            new DelayedTypeComputation(this, classMember, overriddenMembers);
+        _membersBuilder.registerDelayedTypeComputation(computation);
+
+        /// Declared members must be checked to validly override the
+        /// overridden members.
+        _membersBuilder.registerOverrideCheck(
+            classBuilder as SourceClassBuilder, classMember, overriddenMembers);
+      });
+
+      mixinApplicationOverridesMap.forEach(
+          (ClassMember classMember, Set<ClassMember> overriddenMembers) {
+        /// Declared mixed in members must be checked to validly override the
+        /// overridden members.
+        _membersBuilder.registerOverrideCheck(
+            classBuilder as SourceClassBuilder, classMember, overriddenMembers);
+      });
+
+      inheritedImplementsMap.forEach(
+          (ClassMember classMember, Set<ClassMember> overriddenMembers) {
+        /// Concrete members must be checked to validly override the overridden
+        /// members in concrete classes.
+        _membersBuilder.registerOverrideCheck(
+            classBuilder as SourceClassBuilder, classMember, overriddenMembers);
+      });
+    }
+
+    if (!hasInterfaces) {
+      /// All interface members also class members to we don't need to store
+      /// the interface members separately.
+      assert(
+          classMemberMap.length == interfaceMemberMap.length,
+          "Class/interface member mismatch. Class members: "
+          "$classMemberMap, interface members: $interfaceMemberMap.");
+      assert(
+          classSetterMap.length == interfaceSetterMap.length,
+          "Class/interface setter mismatch. Class setters: "
+          "$classSetterMap, interface setters: $interfaceSetterMap.");
+      assert(
+          classMemberMap.keys.every((Name name) =>
+              identical(classMemberMap[name], interfaceMemberMap?[name])),
+          "Class/interface member mismatch. Class members: "
+          "$classMemberMap, interface members: $interfaceMemberMap.");
+      assert(
+          classSetterMap.keys.every((Name name) =>
+              identical(classSetterMap[name], interfaceSetterMap?[name])),
+          "Class/interface setter mismatch. Class setters: "
+          "$classSetterMap, interface setters: $interfaceSetterMap.");
+      interfaceMemberMap = null;
+      interfaceSetterMap = null;
+    }
+
+    // ignore: unnecessary_null_comparison
+    if (abstractMembers != null && !classBuilder.isAbstract) {
+      if (!hasNoSuchMethod) {
+        reportMissingMembers(abstractMembers);
+      } else {
+        installNsmHandlers();
+      }
+    }
+
+    return new ClassMembersNode(
+        classBuilder,
+        classMemberMap,
+        classSetterMap,
+        interfaceMemberMap,
+        interfaceSetterMap,
+        hasNoSuchMethod,
+        dataForTesting);
+  }
+
+  void reportMissingMembers(List<ClassMember> abstractMembers) {
+    Map<String, LocatedMessage> contextMap = <String, LocatedMessage>{};
+    for (ClassMember declaration in unfoldDeclarations(abstractMembers)) {
+      if (isNameVisibleIn(declaration.name, classBuilder.library)) {
+        String name = declaration.fullNameForErrors;
+        String className = declaration.classBuilder.fullNameForErrors;
+        String displayName =
+            declaration.isSetter ? "$className.$name=" : "$className.$name";
+        contextMap[displayName] = templateMissingImplementationCause
+            .withArguments(displayName)
+            .withLocation(
+                declaration.fileUri, declaration.charOffset, name.length);
+      }
+    }
+    if (contextMap.isEmpty) return;
+    List<String> names = new List<String>.from(contextMap.keys)..sort();
+    List<LocatedMessage> context = <LocatedMessage>[];
+    for (int i = 0; i < names.length; i++) {
+      context.add(contextMap[names[i]]!);
+    }
+    classBuilder.addProblem(
+        templateMissingImplementationNotAbstract.withArguments(
+            classBuilder.fullNameForErrors, names),
+        classBuilder.charOffset,
+        classBuilder.fullNameForErrors.length,
+        context: context);
+  }
+
+  void installNsmHandlers() {
+    // TODO(ahe): Implement this.
+  }
+}
+
+class ClassMembersNode {
+  final ClassBuilder classBuilder;
+
+  /// All the members of this class including [classMembers] of its
+  /// superclasses. The members are sorted by [compareDeclarations].
+  final Map<Name, ClassMember> classMemberMap;
+
+  /// Similar to [classMembers] but for setters.
+  final Map<Name, ClassMember> classSetterMap;
+
+  /// All the interface members of this class including [interfaceMembers] of
+  /// its supertypes. The members are sorted by [compareDeclarations].
+  ///
+  /// In addition to the members of [classMembers] this also contains members
+  /// from interfaces.
+  ///
+  /// This may be null, in which case [classMembers] is the interface members.
+  final Map<Name, ClassMember>? interfaceMemberMap;
+
+  /// Similar to [interfaceMembers] but for setters.
+  ///
+  /// This may be null, in which case [classSetters] is the interface setters.
+  final Map<Name, ClassMember>? interfaceSetterMap;
+
+  final bool hasNoSuchMethod;
+
+  final ClassHierarchyNodeDataForTesting? dataForTesting;
+
+  ClassMembersNode(
+      this.classBuilder,
+      this.classMemberMap,
+      this.classSetterMap,
+      this.interfaceMemberMap,
+      this.interfaceSetterMap,
+      this.hasNoSuchMethod,
+      this.dataForTesting);
+
+  @override
+  String toString() {
+    StringBuffer sb = new StringBuffer();
+    sb
+      ..write(classBuilder.fullNameForErrors)
+      ..writeln(":");
+    printMemberMap(classMemberMap, sb, "classMembers");
+    printMemberMap(classSetterMap, sb, "classSetters");
+    if (interfaceMemberMap != null) {
+      printMemberMap(interfaceMemberMap!, sb, "interfaceMembers");
+    }
+    if (interfaceSetterMap != null) {
+      printMemberMap(interfaceSetterMap!, sb, "interfaceSetters");
+    }
+    return "$sb";
+  }
+
+  void printMembers(
+      List<ClassMember> members, StringBuffer sb, String heading) {
+    sb.write("  ");
+    sb.write(heading);
+    sb.writeln(":");
+    for (ClassMember member in members) {
+      sb
+        ..write("    ")
+        ..write(member.classBuilder.fullNameForErrors)
+        ..write(".")
+        ..write(member.fullNameForErrors)
+        ..writeln();
+    }
+  }
+
+  void printMemberMap(
+      Map<Name, ClassMember> memberMap, StringBuffer sb, String heading) {
+    List<ClassMember> members = memberMap.values.toList();
+    members.sort(compareDeclarations);
+    printMembers(members, sb, heading);
+  }
+
+  ClassMember? getInterfaceMember(Name name, bool isSetter) {
+    return isSetter
+        ? (interfaceSetterMap ?? classSetterMap)[name]
+        : (interfaceMemberMap ?? classMemberMap)[name];
+  }
+
+  ClassMember? findMember(Name name, List<ClassMember> declarations) {
+    // TODO(ahe): Consider creating a map or scope. The obvious choice would be
+    // to use scopes, but they don't handle private names correctly.
+
+    // This is a copy of `ClassHierarchy.findMemberByName`.
+    int low = 0, high = declarations.length - 1;
+    while (low <= high) {
+      int mid = low + ((high - low) >> 1);
+      ClassMember pivot = declarations[mid];
+      int comparison = ClassHierarchy.compareNames(name, pivot.name);
+      if (comparison < 0) {
+        high = mid - 1;
+      } else if (comparison > 0) {
+        low = mid + 1;
+      } else if (high != mid) {
+        // Ensure we find the first element of the given name.
+        high = mid;
+      } else {
+        return pivot;
+      }
+    }
+    return null;
+  }
+
+  ClassMember? getDispatchTarget(Name name, bool isSetter) {
+    return isSetter ? classSetterMap[name] : classMemberMap[name];
+  }
+}
+
+class ClassHierarchyNodeDataForTesting {
+  final List<ClassMember> abstractMembers;
+  final Map<ClassMember, Set<ClassMember>> declaredOverrides;
+  final Map<ClassMember, Set<ClassMember>> mixinApplicationOverrides;
+  final Map<ClassMember, Set<ClassMember>> inheritedImplements;
+  final Map<ClassMember, ClassMember> aliasMap = {};
+
+  ClassHierarchyNodeDataForTesting(this.abstractMembers, this.declaredOverrides,
+      this.mixinApplicationOverrides, this.inheritedImplements);
+}
+
+class Tuple {
+  final Name name;
+  ClassMember? _declaredMember;
+  ClassMember? _declaredSetter;
+  ClassMember? _mixedInMember;
+  ClassMember? _mixedInSetter;
+  ClassMember? _extendedMember;
+  ClassMember? _extendedSetter;
+  List<ClassMember>? _implementedMembers;
+  List<ClassMember>? _implementedSetters;
+
+  Tuple.declareMember(ClassMember declaredMember)
+      : assert(!declaredMember.forSetter),
+        this._declaredMember = declaredMember,
+        this.name = declaredMember.name;
+
+  Tuple.mixInMember(ClassMember mixedInMember)
+      : assert(!mixedInMember.forSetter),
+        this._mixedInMember = mixedInMember,
+        this.name = mixedInMember.name;
+
+  Tuple.extendMember(ClassMember extendedMember)
+      : assert(!extendedMember.forSetter),
+        this._extendedMember = extendedMember,
+        this.name = extendedMember.name;
+
+  Tuple.implementMember(ClassMember implementedMember)
+      : assert(!implementedMember.forSetter),
+        this.name = implementedMember.name,
+        _implementedMembers = <ClassMember>[implementedMember];
+
+  Tuple.declareSetter(ClassMember declaredSetter)
+      : assert(declaredSetter.forSetter),
+        this._declaredSetter = declaredSetter,
+        this.name = declaredSetter.name;
+
+  Tuple.mixInSetter(ClassMember mixedInSetter)
+      : assert(mixedInSetter.forSetter),
+        this._mixedInSetter = mixedInSetter,
+        this.name = mixedInSetter.name;
+
+  Tuple.extendSetter(ClassMember extendedSetter)
+      : assert(extendedSetter.forSetter),
+        this._extendedSetter = extendedSetter,
+        this.name = extendedSetter.name;
+
+  Tuple.implementSetter(ClassMember implementedSetter)
+      : assert(implementedSetter.forSetter),
+        this.name = implementedSetter.name,
+        _implementedSetters = <ClassMember>[implementedSetter];
+
+  ClassMember? get declaredMember => _declaredMember;
+
+  void set declaredMember(ClassMember? value) {
+    assert(!value!.forSetter);
+    assert(
+        _declaredMember == null,
+        "Declared member already set to $_declaredMember, "
+        "trying to set it to $value.");
+    _declaredMember = value;
+  }
+
+  ClassMember? get declaredSetter => _declaredSetter;
+
+  void set declaredSetter(ClassMember? value) {
+    assert(value!.forSetter);
+    assert(
+        _declaredSetter == null,
+        "Declared setter already set to $_declaredSetter, "
+        "trying to set it to $value.");
+    _declaredSetter = value;
+  }
+
+  ClassMember? get extendedMember => _extendedMember;
+
+  void set extendedMember(ClassMember? value) {
+    assert(!value!.forSetter);
+    assert(
+        _extendedMember == null,
+        "Extended member already set to $_extendedMember, "
+        "trying to set it to $value.");
+    _extendedMember = value;
+  }
+
+  ClassMember? get extendedSetter => _extendedSetter;
+
+  void set extendedSetter(ClassMember? value) {
+    assert(value!.forSetter);
+    assert(
+        _extendedSetter == null,
+        "Extended setter already set to $_extendedSetter, "
+        "trying to set it to $value.");
+    _extendedSetter = value;
+  }
+
+  ClassMember? get mixedInMember => _mixedInMember;
+
+  void set mixedInMember(ClassMember? value) {
+    assert(!value!.forSetter);
+    assert(
+        _mixedInMember == null,
+        "Mixed in member already set to $_mixedInMember, "
+        "trying to set it to $value.");
+    _mixedInMember = value;
+  }
+
+  ClassMember? get mixedInSetter => _mixedInSetter;
+
+  void set mixedInSetter(ClassMember? value) {
+    assert(value!.forSetter);
+    assert(
+        _mixedInSetter == null,
+        "Mixed in setter already set to $_mixedInSetter, "
+        "trying to set it to $value.");
+    _mixedInSetter = value;
+  }
+
+  List<ClassMember>? get implementedMembers => _implementedMembers;
+
+  void addImplementedMember(ClassMember value) {
+    assert(!value.forSetter);
+    _implementedMembers ??= <ClassMember>[];
+    _implementedMembers!.add(value);
+  }
+
+  List<ClassMember>? get implementedSetters => _implementedSetters;
+
+  void addImplementedSetter(ClassMember value) {
+    assert(value.forSetter);
+    _implementedSetters ??= <ClassMember>[];
+    _implementedSetters!.add(value);
+  }
+
+  @override
+  String toString() {
+    StringBuffer sb = new StringBuffer();
+    String comma = '';
+    sb.write('Tuple(');
+    if (_declaredMember != null) {
+      sb.write(comma);
+      sb.write('declaredMember=');
+      sb.write(_declaredMember);
+      comma = ',';
+    }
+    if (_declaredSetter != null) {
+      sb.write(comma);
+      sb.write('declaredSetter=');
+      sb.write(_declaredSetter);
+      comma = ',';
+    }
+    if (_mixedInMember != null) {
+      sb.write(comma);
+      sb.write('mixedInMember=');
+      sb.write(_mixedInMember);
+      comma = ',';
+    }
+    if (_mixedInSetter != null) {
+      sb.write(comma);
+      sb.write('mixedInSetter=');
+      sb.write(_mixedInSetter);
+      comma = ',';
+    }
+    if (_extendedMember != null) {
+      sb.write(comma);
+      sb.write('extendedMember=');
+      sb.write(_extendedMember);
+      comma = ',';
+    }
+    if (_extendedSetter != null) {
+      sb.write(comma);
+      sb.write('extendedSetter=');
+      sb.write(_extendedSetter);
+      comma = ',';
+    }
+    if (_implementedMembers != null) {
+      sb.write(comma);
+      sb.write('implementedMembers=');
+      sb.write(_implementedMembers);
+      comma = ',';
+    }
+    if (_implementedSetters != null) {
+      sb.write(comma);
+      sb.write('implementedSetters=');
+      sb.write(_implementedSetters);
+      comma = ',';
+    }
+    sb.write(')');
+    return sb.toString();
+  }
+}
+
+Set<ClassMember> toSet(
+    ClassBuilder classBuilder, Iterable<ClassMember> members) {
+  Set<ClassMember> result = <ClassMember>{};
+  _toSet(classBuilder, members, result);
+  return result;
+}
+
+void _toSet(ClassBuilder classBuilder, Iterable<ClassMember> members,
+    Set<ClassMember> result) {
+  for (ClassMember member in members) {
+    if (member.hasDeclarations && classBuilder == member.classBuilder) {
+      _toSet(classBuilder, member.declarations, result);
+    } else {
+      result.add(member);
+    }
+  }
+}
+
+void reportCantInferParameterType(ClassBuilder cls,
+    FormalParameterBuilder parameter, Iterable<ClassMember> overriddenMembers) {
+  String name = parameter.name;
+  List<LocatedMessage> context = overriddenMembers
+      .map((ClassMember overriddenMember) {
+        return messageDeclaredMemberConflictsWithOverriddenMembersCause
+            .withLocation(overriddenMember.fileUri, overriddenMember.charOffset,
+                overriddenMember.fullNameForErrors.length);
+      })
+      // Call toSet to avoid duplicate context for instance of fields that are
+      // overridden both as getters and setters.
+      .toSet()
+      .toList();
+  cls.addProblem(
+      templateCantInferTypeDueToNoCombinedSignature.withArguments(name),
+      parameter.charOffset,
+      name.length,
+      wasHandled: true,
+      context: context);
+}
+
+void reportCantInferTypes(ClassBuilder cls, SourceProcedureBuilder member,
+    Iterable<ClassMember> overriddenMembers) {
+  String name = member.fullNameForErrors;
+  List<LocatedMessage> context = overriddenMembers
+      .map((ClassMember overriddenMember) {
+        return messageDeclaredMemberConflictsWithOverriddenMembersCause
+            .withLocation(overriddenMember.fileUri, overriddenMember.charOffset,
+                overriddenMember.fullNameForErrors.length);
+      })
+      // Call toSet to avoid duplicate context for instance of fields that are
+      // overridden both as getters and setters.
+      .toSet()
+      .toList();
+  cls.addProblem(
+      templateCantInferTypesDueToNoCombinedSignature.withArguments(name),
+      member.charOffset,
+      name.length,
+      wasHandled: true,
+      context: context);
+}
+
+void reportCantInferReturnType(ClassBuilder cls, SourceProcedureBuilder member,
+    Iterable<ClassMember> overriddenMembers) {
+  String name = member.fullNameForErrors;
+  List<LocatedMessage> context = overriddenMembers
+      .map((ClassMember overriddenMember) {
+        return messageDeclaredMemberConflictsWithOverriddenMembersCause
+            .withLocation(overriddenMember.fileUri, overriddenMember.charOffset,
+                overriddenMember.fullNameForErrors.length);
+      })
+      // Call toSet to avoid duplicate context for instance of fields that are
+      // overridden both as getters and setters.
+      .toSet()
+      .toList();
+  // // TODO(ahe): The following is for debugging, but could be cleaned up and
+  // // used to improve this error message in general.
+  //
+  // context = <LocatedMessage>[];
+  // ClassHierarchyNode supernode = hierarchy.getNodeFromType(cls.supertype);
+  // // TODO(ahe): Wrong template.
+  // Template<Message Function(String)> template =
+  //     templateMissingImplementationCause;
+  // if (supernode != null) {
+  //   Declaration superMember =
+  //       supernode.getInterfaceMember(new Name(name), false);
+  //   if (superMember != null) {
+  //     context.add(template
+  //         .withArguments(name)
+  //         .withLocation(
+  //             superMember.fileUri, superMember.charOffset, name.length));
+  //   }
+  //   superMember = supernode.getInterfaceMember(new Name(name), true);
+  //   if (superMember != null) {
+  //     context.add(template
+  //         .withArguments(name)
+  //         .withLocation(
+  //             superMember.fileUri, superMember.charOffset, name.length));
+  //   }
+  // }
+  // List<TypeBuilder> directInterfaces = cls.interfaces;
+  // for (int i = 0; i < directInterfaces.length; i++) {
+  //   ClassHierarchyNode supernode =
+  //       hierarchy.getNodeFromType(directInterfaces[i]);
+  //   if (supernode != null) {
+  //     Declaration superMember =
+  //         supernode.getInterfaceMember(new Name(name), false);
+  //     if (superMember != null) {
+  //       context.add(template
+  //           .withArguments(name)
+  //           .withLocation(
+  //               superMember.fileUri, superMember.charOffset, name.length));
+  //     }
+  //     superMember = supernode.getInterfaceMember(new Name(name), true);
+  //     if (superMember != null) {
+  //       context.add(template
+  //           .withArguments(name)
+  //           .withLocation(
+  //               superMember.fileUri, superMember.charOffset, name.length));
+  //     }
+  //   }
+  // }
+  cls.addProblem(
+      templateCantInferReturnTypeDueToNoCombinedSignature.withArguments(name),
+      member.charOffset,
+      name.length,
+      wasHandled: true,
+      context: context);
+}
+
+void reportCantInferFieldType(ClassBuilder cls, SourceFieldBuilder member,
+    Iterable<ClassMember> overriddenMembers) {
+  List<LocatedMessage> context = overriddenMembers
+      .map((ClassMember overriddenMember) {
+        return messageDeclaredMemberConflictsWithOverriddenMembersCause
+            .withLocation(overriddenMember.fileUri, overriddenMember.charOffset,
+                overriddenMember.fullNameForErrors.length);
+      })
+      // Call toSet to avoid duplicate context for instance of fields that are
+      // overridden both as getters and setters.
+      .toSet()
+      .toList();
+  String name = member.fullNameForErrors;
+  cls.addProblem(
+      templateCantInferTypeDueToNoCombinedSignature.withArguments(name),
+      member.charOffset,
+      name.length,
+      wasHandled: true,
+      context: context);
+}
+
+List<LocatedMessage> _inheritedConflictContext(ClassMember a, ClassMember b) {
+  int length = a.fullNameForErrors.length;
+  // TODO(ahe): Delete this method when it isn't used by [InterfaceResolver].
+  int compare = "${a.fileUri}".compareTo("${b.fileUri}");
+  if (compare == 0) {
+    compare = a.charOffset.compareTo(b.charOffset);
+  }
+  ClassMember first;
+  ClassMember second;
+  if (compare < 0) {
+    first = a;
+    second = b;
+  } else {
+    first = b;
+    second = a;
+  }
+  return <LocatedMessage>[
+    messageInheritedMembersConflictCause1.withLocation(
+        first.fileUri, first.charOffset, length),
+    messageInheritedMembersConflictCause2.withLocation(
+        second.fileUri, second.charOffset, length),
+  ];
+}
+
+bool isNameVisibleIn(Name name, LibraryBuilder libraryBuilder) {
+  return !name.isPrivate || name.library == libraryBuilder.library;
+}
+
+int compareDeclarations(ClassMember a, ClassMember b) {
+  if (a == b) return 0;
+  return ClassHierarchy.compareNames(a.name, b.name);
+}
+
+Set<ClassMember> unfoldDeclarations(Iterable<ClassMember> members) {
+  Set<ClassMember> result = <ClassMember>{};
+  _unfoldDeclarations(members, result);
+  return result;
+}
+
+void _unfoldDeclarations(
+    Iterable<ClassMember> members, Set<ClassMember> result) {
+  for (ClassMember member in members) {
+    if (member.hasDeclarations) {
+      _unfoldDeclarations(member.declarations, result);
+    } else {
+      result.add(member);
+    }
+  }
+}
diff --git a/pkg/front_end/lib/src/fasta/kernel/hierarchy/mixin_inferrer.dart b/pkg/front_end/lib/src/fasta/kernel/hierarchy/mixin_inferrer.dart
new file mode 100644
index 0000000..f8974cc
--- /dev/null
+++ b/pkg/front_end/lib/src/fasta/kernel/hierarchy/mixin_inferrer.dart
@@ -0,0 +1,103 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library fasta.class_hierarchy_builder;
+
+import 'package:kernel/ast.dart';
+import 'package:kernel/core_types.dart' show CoreTypes;
+import 'package:kernel/src/standard_bounds.dart';
+import 'package:kernel/type_environment.dart';
+
+import '../../builder/class_builder.dart';
+import '../../messages.dart' show Message;
+import '../../type_inference/standard_bounds.dart'
+    show TypeSchemaStandardBounds;
+import '../../type_inference/type_constraint_gatherer.dart'
+    show TypeConstraintGatherer;
+import '../../type_inference/type_inferrer.dart' show MixinInferrer;
+import '../../type_inference/type_schema_environment.dart' show TypeConstraint;
+import 'hierarchy_builder.dart';
+
+class BuilderMixinInferrer extends MixinInferrer {
+  final ClassBuilder cls;
+
+  BuilderMixinInferrer(
+      this.cls, CoreTypes coreTypes, TypeBuilderConstraintGatherer gatherer)
+      : super(coreTypes, gatherer);
+
+  @override
+  Supertype? asInstantiationOf(Supertype type, Class superclass) {
+    List<DartType>? arguments =
+        gatherer.getTypeArgumentsAsInstanceOf(type.asInterfaceType, superclass);
+    if (arguments == null) return null;
+    return new Supertype(superclass, arguments);
+  }
+
+  @override
+  void reportProblem(Message message, Class kernelClass) {
+    int length = cls.isMixinApplication ? 1 : cls.fullNameForErrors.length;
+    cls.addProblem(message, cls.charOffset, length);
+  }
+}
+
+class TypeBuilderConstraintGatherer extends TypeConstraintGatherer
+    with StandardBounds, TypeSchemaStandardBounds {
+  @override
+  final ClassHierarchyBuilder hierarchy;
+
+  TypeBuilderConstraintGatherer(this.hierarchy,
+      Iterable<TypeParameter> typeParameters, Library currentLibrary)
+      : super.subclassing(typeParameters, currentLibrary);
+
+  @override
+  CoreTypes get coreTypes => hierarchy.coreTypes;
+
+  @override
+  void addLowerBound(
+      TypeConstraint constraint, DartType lower, Library clientLibrary) {
+    constraint.lower =
+        getStandardUpperBound(constraint.lower, lower, clientLibrary);
+  }
+
+  @override
+  void addUpperBound(
+      TypeConstraint constraint, DartType upper, Library clientLibrary) {
+    constraint.upper =
+        getStandardLowerBound(constraint.upper, upper, clientLibrary);
+  }
+
+  @override
+  Member? getInterfaceMember(Class class_, Name name, {bool setter: false}) {
+    return null;
+  }
+
+  @override
+  InterfaceType getTypeAsInstanceOf(InterfaceType type, Class superclass,
+      Library clientLibrary, CoreTypes coreTypes) {
+    return hierarchy.getTypeAsInstanceOf(type, superclass, clientLibrary);
+  }
+
+  @override
+  List<DartType>? getTypeArgumentsAsInstanceOf(
+      InterfaceType type, Class superclass) {
+    return hierarchy.getTypeArgumentsAsInstanceOf(type, superclass);
+  }
+
+  @override
+  InterfaceType futureType(DartType type, Nullability nullability) {
+    return new InterfaceType(
+        hierarchy.futureClass, nullability, <DartType>[type]);
+  }
+
+  @override
+  bool isSubtypeOf(
+      DartType subtype, DartType supertype, SubtypeCheckMode mode) {
+    return hierarchy.types.isSubtypeOf(subtype, supertype, mode);
+  }
+
+  @override
+  bool areMutualSubtypes(DartType s, DartType t, SubtypeCheckMode mode) {
+    return isSubtypeOf(s, t, mode) && isSubtypeOf(t, s, mode);
+  }
+}
diff --git a/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart b/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart
index 9440adf..27f8d35 100644
--- a/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart
@@ -315,8 +315,7 @@
       Uri translatedEntryPoint =
           getEntryPointUri(entryPoint, issueProblem: true);
       result.add(translatedEntryPoint);
-      loader.read(translatedEntryPoint, -1,
-          accessorUri: loader.firstUri,
+      loader.readAsEntryPoint(translatedEntryPoint,
           fileUri: translatedEntryPoint != entryPoint ? entryPoint : null);
     }
     return result;
@@ -361,23 +360,6 @@
     return entryPoint;
   }
 
-  /// Returns classes defined in libraries in [loader].
-  List<SourceClassBuilder> collectMyClasses() {
-    List<SourceClassBuilder> result = <SourceClassBuilder>[];
-    for (LibraryBuilder library in loader.libraryBuilders) {
-      if (library.loader == loader) {
-        Iterator<Builder> iterator = library.iterator;
-        while (iterator.moveNext()) {
-          Builder member = iterator.current;
-          if (member is SourceClassBuilder && !member.isPatch) {
-            result.add(member);
-          }
-        }
-      }
-    }
-    return result;
-  }
-
   /// The class [cls] is involved in a cyclic definition. This method should
   /// ensure that the cycle is broken, for example, by removing superclass and
   /// implemented interfaces.
@@ -460,10 +442,10 @@
       finishSynthesizedParameters();
       loader.finishDeferredLoadTearoffs();
       loader.finishNoSuchMethodForwarders();
-      List<SourceClassBuilder> myClasses = collectMyClasses();
+      List<SourceClassBuilder> sourceClasses = loader.collectSourceClasses();
       loader.finishNativeMethods();
       loader.finishPatchMethods();
-      finishAllConstructors(myClasses);
+      finishAllConstructors(sourceClasses);
       runBuildTransformations();
 
       if (verify) this.verify();
@@ -625,33 +607,8 @@
 
   void installDefaultSupertypes() {
     Class objectClass = this.objectClass;
-    for (LibraryBuilder library in loader.libraryBuilders) {
-      if (library.loader == loader) {
-        Iterator<Builder> iterator = library.iterator;
-        while (iterator.moveNext()) {
-          Builder declaration = iterator.current;
-          if (declaration is SourceClassBuilder) {
-            Class cls = declaration.cls;
-            if (cls != objectClass) {
-              cls.supertype ??= objectClass.asRawSupertype;
-              declaration.supertypeBuilder ??= new NamedTypeBuilder(
-                  "Object",
-                  const NullabilityBuilder.omitted(),
-                  /* arguments = */ null,
-                  /* fileUri = */ null,
-                  /* charOffset = */ null,
-                  instanceTypeVariableAccess:
-                      InstanceTypeVariableAccessState.Unexpected)
-                ..bind(objectClassBuilder);
-            }
-            if (declaration.isMixinApplication) {
-              cls.mixedInType = declaration.mixedInTypeBuilder!
-                  .buildMixedInType(
-                      library, declaration.charOffset, declaration.fileUri);
-            }
-          }
-        }
-      }
+    for (SourceLibraryBuilder library in loader.sourceLibraryBuilders) {
+      library.installDefaultSupertypes(objectClassBuilder, objectClass);
     }
     ticker.logMs("Installed Object as implicit superclass");
   }
diff --git a/pkg/front_end/lib/src/fasta/kernel/verifier.dart b/pkg/front_end/lib/src/fasta/kernel/verifier.dart
index 7543cd9..ae560e2 100644
--- a/pkg/front_end/lib/src/fasta/kernel/verifier.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/verifier.dart
@@ -29,7 +29,10 @@
 import '../type_inference/type_schema.dart' show UnknownType;
 
 import 'redirecting_factory_body.dart'
-    show RedirectingFactoryBody, isRedirectingFactory;
+    show
+        RedirectingFactoryBody,
+        isRedirectingFactory,
+        isRedirectingFactoryField;
 
 List<LocatedMessage> verifyComponent(Component component, Target target,
     {bool? isOutline, bool? afterConst, bool skipPlatform: false}) {
@@ -431,6 +434,89 @@
     exitTreeNode(node);
   }
 
+  void _checkConstructorTearOff(Node node, Member tearOffTarget) {
+    if (tearOffTarget.enclosingLibrary.importUri.scheme == 'dart') {
+      // Platform libraries are not compilation with test flags and might
+      // contain tear-offs not expected when testing lowerings.
+      return;
+    }
+    if (currentMember != null && isRedirectingFactoryField(currentMember!)) {
+      // The encoding of the redirecting factory field uses
+      // [ConstructorTearOffConstant] nodes also when lowerings are enabled.
+      return;
+    }
+    if (tearOffTarget is Constructor &&
+        target.isConstructorTearOffLoweringEnabled) {
+      problem(
+          node is TreeNode ? node : getLastSeenTreeNode(),
+          '${node.runtimeType} nodes for generative constructors should be '
+          'lowered for target "${target.name}".');
+    }
+    if (tearOffTarget is Procedure &&
+        tearOffTarget.isFactory &&
+        target.isFactoryTearOffLoweringEnabled) {
+      problem(
+          node is TreeNode ? node : getLastSeenTreeNode(),
+          '${node.runtimeType} nodes for factory constructors should be '
+          'lowered for target "${target.name}".');
+    }
+  }
+
+  @override
+  void visitConstructorTearOff(ConstructorTearOff node) {
+    _checkConstructorTearOff(node, node.target);
+    super.visitConstructorTearOff(node);
+  }
+
+  @override
+  void visitConstructorTearOffConstant(ConstructorTearOffConstant node) {
+    _checkConstructorTearOff(node, node.target);
+    super.visitConstructorTearOffConstant(node);
+  }
+
+  void _checkTypedefTearOff(Node node) {
+    if (target.isTypedefTearOffLoweringEnabled) {
+      problem(
+          node is TreeNode ? node : getLastSeenTreeNode(),
+          '${node.runtimeType} nodes for typedefs should be '
+          'lowered for target "${target.name}".');
+    }
+  }
+
+  @override
+  void visitTypedefTearOff(TypedefTearOff node) {
+    _checkTypedefTearOff(node);
+    super.visitTypedefTearOff(node);
+  }
+
+  @override
+  void visitTypedefTearOffConstant(TypedefTearOffConstant node) {
+    _checkTypedefTearOff(node);
+    super.visitTypedefTearOffConstant(node);
+  }
+
+  void _checkRedirectingFactoryTearOff(Node node) {
+    if (target.isRedirectingFactoryTearOffLoweringEnabled) {
+      problem(
+          node is TreeNode ? node : getLastSeenTreeNode(),
+          'ConstructorTearOff nodes for redirecting factories should be '
+          'lowered for target "${target.name}".');
+    }
+  }
+
+  @override
+  void visitRedirectingFactoryTearOff(RedirectingFactoryTearOff node) {
+    _checkRedirectingFactoryTearOff(node);
+    super.visitRedirectingFactoryTearOff(node);
+  }
+
+  @override
+  void visitRedirectingFactoryTearOffConstant(
+      RedirectingFactoryTearOffConstant node) {
+    _checkRedirectingFactoryTearOff(node);
+    super.visitRedirectingFactoryTearOffConstant(node);
+  }
+
   @override
   void defaultTreeNode(TreeNode node) {
     enterTreeNode(node);
diff --git a/pkg/front_end/lib/src/fasta/modifier.dart b/pkg/front_end/lib/src/fasta/modifier.dart
index 127ce5c..1d0b3f7 100644
--- a/pkg/front_end/lib/src/fasta/modifier.dart
+++ b/pkg/front_end/lib/src/fasta/modifier.dart
@@ -50,6 +50,10 @@
 /// constructor.
 const int declaresConstConstructorMask = initializingFormalMask << 1;
 
+/// Not a modifier, used by formal parameters to track if they are
+/// super-parameter initializers.
+const int superInitializingFormalMask = declaresConstConstructorMask << 1;
+
 /// Not a real modifier, and by setting it to zero, it is automatically ignored
 /// by [Modifier.toMask] below.
 const int varMask = 0;
diff --git a/pkg/front_end/lib/src/fasta/scope.dart b/pkg/front_end/lib/src/fasta/scope.dart
index db65cb2..f69cc83 100644
--- a/pkg/front_end/lib/src/fasta/scope.dart
+++ b/pkg/front_end/lib/src/fasta/scope.dart
@@ -14,7 +14,7 @@
 import 'builder/name_iterator.dart';
 import 'builder/type_variable_builder.dart';
 import 'kernel/body_builder.dart' show JumpTarget;
-import 'kernel/class_hierarchy_builder.dart' show ClassMember;
+import 'kernel/hierarchy/class_member.dart' show ClassMember;
 import 'kernel/kernel_helper.dart';
 import 'util/helpers.dart' show DelayedActionPerformer;
 
diff --git a/pkg/front_end/lib/src/fasta/source/diet_listener.dart b/pkg/front_end/lib/src/fasta/source/diet_listener.dart
index 86edd9f..ae3196c 100644
--- a/pkg/front_end/lib/src/fasta/source/diet_listener.dart
+++ b/pkg/front_end/lib/src/fasta/source/diet_listener.dart
@@ -918,7 +918,8 @@
   }
 
   @override
-  void beginClassDeclaration(Token begin, Token? abstractToken, Token name) {
+  void beginClassDeclaration(
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {
     debugEvent("beginClassDeclaration");
     push(begin);
   }
diff --git a/pkg/front_end/lib/src/fasta/source/outline_builder.dart b/pkg/front_end/lib/src/fasta/source/outline_builder.dart
index 0d7fc82..82bbe12 100644
--- a/pkg/front_end/lib/src/fasta/source/outline_builder.dart
+++ b/pkg/front_end/lib/src/fasta/source/outline_builder.dart
@@ -814,7 +814,8 @@
   }
 
   @override
-  void beginClassDeclaration(Token begin, Token? abstractToken, Token name) {
+  void beginClassDeclaration(
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {
     debugEvent("beginClassDeclaration");
     popDeclarationContext(
         DeclarationContext.ClassOrMixinOrNamedMixinApplication);
@@ -827,6 +828,18 @@
     libraryBuilder.setCurrentClassName(name.lexeme);
     inAbstractClass = abstractToken != null;
     push(abstractToken != null ? abstractMask : 0);
+    if (macroToken != null && !libraryBuilder.enableMacrosInLibrary) {
+      // TODO(johnniwinther): We should emit a different message when the
+      // experiment is not released yet. The current message indicates that
+      // changing the sdk version can solve the problem.
+      addProblem(
+          templateExperimentNotEnabled.withArguments(
+              'macros', libraryBuilder.enableMacrosVersionInLibrary.toText()),
+          macroToken.next!.charOffset,
+          macroToken.next!.length);
+      macroToken = null;
+    }
+    push(macroToken ?? NullValue.Token);
   }
 
   @override
@@ -899,7 +912,7 @@
 
   @override
   void beginNamedMixinApplication(
-      Token begin, Token? abstractToken, Token name) {
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {
     debugEvent("beginNamedMixinApplication");
     popDeclarationContext(
         DeclarationContext.ClassOrMixinOrNamedMixinApplication);
@@ -910,6 +923,15 @@
     libraryBuilder.currentTypeParameterScopeBuilder.markAsNamedMixinApplication(
         name.lexeme, name.charOffset, typeVariables);
     push(abstractToken != null ? abstractMask : 0);
+    if (macroToken != null && !libraryBuilder.enableMacrosInLibrary) {
+      addProblem(
+          templateExperimentNotEnabled.withArguments(
+              'macros', libraryBuilder.enableMacrosVersionInLibrary.toText()),
+          macroToken.next!.charOffset,
+          macroToken.next!.length);
+      macroToken = null;
+    }
+    push(macroToken ?? NullValue.Token);
   }
 
   @override
@@ -1042,10 +1064,26 @@
   @override
   void endClassDeclaration(Token beginToken, Token endToken) {
     debugEvent("endClassDeclaration");
+    assert(checkState(beginToken, [
+      /* interfaces */ ValueKinds.TypeBuilderListOrNull,
+      /* supertype offset */ ValueKinds.Integer,
+      /* supertype */ unionOfKinds([
+        ValueKinds.TypeBuilderOrNull,
+        ValueKinds.ParserRecovery,
+      ]),
+      /* macro token */ ValueKinds.TokenOrNull,
+      /* modifiers */ ValueKinds.Integer,
+      /* type variables */ ValueKinds.TypeVariableListOrNull,
+      /* name offset */ ValueKinds.Integer,
+      /* name */ ValueKinds.NameOrParserRecovery,
+      /* metadata */ ValueKinds.MetadataListOrNull,
+    ]));
+
     List<TypeBuilder>? interfaces =
         pop(NullValue.TypeBuilderList) as List<TypeBuilder>?;
     int supertypeOffset = popCharOffset();
     TypeBuilder? supertype = nullIfParserRecovery(pop()) as TypeBuilder?;
+    Token? macroToken = pop(NullValue.Token) as Token?;
     int modifiers = pop() as int;
     List<TypeVariableBuilder>? typeVariables =
         pop() as List<TypeVariableBuilder>?;
@@ -1122,7 +1160,8 @@
           startCharOffset,
           nameOffset,
           endToken.charOffset,
-          supertypeOffset);
+          supertypeOffset,
+          isMacro: macroToken != null);
     }
     libraryBuilder.setCurrentClassName(null);
     popDeclarationContext(DeclarationContext.Class);
@@ -1880,9 +1919,25 @@
   void endNamedMixinApplication(Token beginToken, Token classKeyword,
       Token equals, Token? implementsKeyword, Token endToken) {
     debugEvent("endNamedMixinApplication");
+    assert(checkState(beginToken, [
+      if (implementsKeyword != null)
+        /* interfaces */ ValueKinds.TypeBuilderListOrNull,
+      /* mixin application */ unionOfKinds([
+        ValueKinds.ParserRecovery,
+        ValueKinds.TypeBuilder,
+      ]),
+      /* macro token */ ValueKinds.TokenOrNull,
+      /* modifiers */ ValueKinds.Integer,
+      /* type variables */ ValueKinds.TypeVariableListOrNull,
+      /* name offset */ ValueKinds.Integer,
+      /* name */ ValueKinds.NameOrParserRecovery,
+      /* metadata */ ValueKinds.MetadataListOrNull,
+    ]));
+
     List<TypeBuilder>? interfaces =
         popIfNotNull(implementsKeyword) as List<TypeBuilder>?;
     Object? mixinApplication = pop();
+    Token? macroToken = pop(NullValue.Token) as Token?;
     int modifiers = pop() as int;
     List<TypeVariableBuilder>? typeVariables =
         pop() as List<TypeVariableBuilder>?;
@@ -1950,7 +2005,8 @@
           interfaces,
           startCharOffset,
           charOffset,
-          charEndOffset);
+          charEndOffset,
+          isMacro: macroToken != null);
     }
     popDeclarationContext(DeclarationContext.NamedMixinApplication);
   }
@@ -2104,6 +2160,7 @@
           type,
           name == null ? FormalParameterBuilder.noNameSentinel : name as String,
           thisKeyword != null,
+          superKeyword != null,
           charOffset,
           initializerStart));
     }
diff --git a/pkg/front_end/lib/src/fasta/source/source_class_builder.dart b/pkg/front_end/lib/src/fasta/source/source_class_builder.dart
index a7d6ce8..6c5157d 100644
--- a/pkg/front_end/lib/src/fasta/source/source_class_builder.dart
+++ b/pkg/front_end/lib/src/fasta/source/source_class_builder.dart
@@ -5,7 +5,8 @@
 library fasta.source_class_builder;
 
 import 'package:kernel/ast.dart';
-import 'package:kernel/class_hierarchy.dart' show ClassHierarchy;
+import 'package:kernel/class_hierarchy.dart'
+    show ClassHierarchy, ClassHierarchyMembers;
 import 'package:kernel/reference_from_index.dart' show IndexedClass;
 import 'package:kernel/src/bounds_checks.dart';
 import 'package:kernel/src/legacy_erasure.dart';
@@ -99,26 +100,30 @@
 
   final IndexedClass? referencesFromIndexed;
 
+  @override
+  final bool isMacro;
+
   SourceClassBuilder(
-    List<MetadataBuilder>? metadata,
-    int modifiers,
-    String name,
-    List<TypeVariableBuilder>? typeVariables,
-    TypeBuilder? supertype,
-    List<TypeBuilder>? interfaces,
-    List<TypeBuilder>? onTypes,
-    Scope scope,
-    ConstructorScope constructors,
-    SourceLibraryBuilder parent,
-    this.constructorReferences,
-    int startCharOffset,
-    int nameOffset,
-    int charEndOffset,
-    this.referencesFromIndexed, {
-    Class? cls,
-    this.mixedInTypeBuilder,
-    this.isMixinDeclaration = false,
-  })  : actualCls = initializeClass(cls, typeVariables, name, parent,
+      List<MetadataBuilder>? metadata,
+      int modifiers,
+      String name,
+      List<TypeVariableBuilder>? typeVariables,
+      TypeBuilder? supertype,
+      List<TypeBuilder>? interfaces,
+      List<TypeBuilder>? onTypes,
+      Scope scope,
+      ConstructorScope constructors,
+      SourceLibraryBuilder parent,
+      this.constructorReferences,
+      int startCharOffset,
+      int nameOffset,
+      int charEndOffset,
+      this.referencesFromIndexed,
+      {Class? cls,
+      this.mixedInTypeBuilder,
+      this.isMixinDeclaration = false,
+      this.isMacro: false})
+      : actualCls = initializeClass(cls, typeVariables, name, parent,
             startCharOffset, nameOffset, charEndOffset, referencesFromIndexed),
         super(metadata, modifiers, name, typeVariables, supertype, interfaces,
             onTypes, scope, constructors, parent, nameOffset) {
@@ -238,6 +243,7 @@
     // TODO(ahe): If `cls.supertype` is null, and this isn't Object, report a
     // compile-time error.
     cls.isAbstract = isAbstract;
+    cls.isMacro = isMacro;
     if (interfaceBuilders != null) {
       for (int i = 0; i < interfaceBuilders!.length; ++i) {
         interfaceBuilders![i] = checkSupertype(interfaceBuilders![i]);
@@ -912,7 +918,6 @@
         new ConstructorTearOff(constructorBuilder.member)..parent = literal);
   }
 
-  @override
   int resolveConstructors(SourceLibraryBuilder library) {
     if (constructorReferences == null) return 0;
     for (ConstructorReferenceBuilder ref in constructorReferences!) {
@@ -1002,8 +1007,13 @@
     return count;
   }
 
-  void checkOverride(Types types, Member declaredMember, Member interfaceMember,
-      bool isSetter, callback(Member interfaceMember, bool isSetter),
+  void checkOverride(
+      Types types,
+      ClassHierarchyMembers memberHierarchy,
+      Member declaredMember,
+      Member interfaceMember,
+      bool isSetter,
+      callback(Member interfaceMember, bool isSetter),
       {required bool isInterfaceCheck,
       required bool declaredNeedsLegacyErasure}) {
     // ignore: unnecessary_null_comparison
@@ -1031,7 +1041,8 @@
               isInterfaceCheck,
               declaredNeedsLegacyErasure);
           if (seenCovariant) {
-            handleSeenCovariant(types, interfaceMember, isSetter, callback);
+            handleSeenCovariant(
+                memberHierarchy, interfaceMember, isSetter, callback);
           }
         } else if (declaredMember.kind == ProcedureKind.Getter) {
           checkGetterOverride(
@@ -1050,7 +1061,8 @@
               isInterfaceCheck,
               declaredNeedsLegacyErasure);
           if (seenCovariant) {
-            handleSeenCovariant(types, interfaceMember, isSetter, callback);
+            handleSeenCovariant(
+                memberHierarchy, interfaceMember, isSetter, callback);
           }
         } else {
           assert(
@@ -1090,7 +1102,8 @@
             isInterfaceCheck,
             declaredNeedsLegacyErasure);
         if (seenCovariant) {
-          handleSeenCovariant(types, interfaceMember, isSetter, callback);
+          handleSeenCovariant(
+              memberHierarchy, interfaceMember, isSetter, callback);
         }
       }
     }
diff --git a/pkg/front_end/lib/src/fasta/source/source_library_builder.dart b/pkg/front_end/lib/src/fasta/source/source_library_builder.dart
index cf7b0ba..3c68b27 100644
--- a/pkg/front_end/lib/src/fasta/source/source_library_builder.dart
+++ b/pkg/front_end/lib/src/fasta/source/source_library_builder.dart
@@ -17,6 +17,7 @@
 import 'package:kernel/class_hierarchy.dart' show ClassHierarchy;
 
 import 'package:kernel/clone.dart' show CloneVisitorNotMembers;
+import 'package:kernel/core_types.dart';
 
 import 'package:kernel/reference_from_index.dart'
     show IndexedClass, IndexedContainer, IndexedLibrary;
@@ -80,10 +81,11 @@
 
 import '../import.dart' show Import;
 
-import '../kernel/class_hierarchy_builder.dart';
+import '../kernel/hierarchy/members_builder.dart';
 import '../kernel/constructor_tearoff_lowering.dart';
 import '../kernel/implicit_field_type.dart';
 import '../kernel/internal_ast.dart';
+import '../kernel/kernel_helper.dart';
 import '../kernel/load_library_builder.dart';
 import '../kernel/type_algorithms.dart'
     show
@@ -106,6 +108,7 @@
         declaresConstConstructorMask,
         hasInitializerMask,
         initializingFormalMask,
+        superInitializingFormalMask,
         lateMask,
         mixinDeclarationMask,
         namedMixinApplicationMask,
@@ -121,6 +124,7 @@
 
 import '../type_inference/type_inferrer.dart' show TypeInferrerImpl;
 
+import '../util/helpers.dart';
 import 'name_scheme.dart';
 import 'source_class_builder.dart' show SourceClassBuilder;
 import 'source_extension_builder.dart';
@@ -180,7 +184,7 @@
   @override
   final Library library;
 
-  final SourceLibraryBuilder? actualOrigin;
+  final SourceLibraryBuilder? _origin;
 
   final List<FunctionBuilder> nativeMethods = <FunctionBuilder>[];
 
@@ -255,13 +259,15 @@
   /// [forEachExtensionInScope].
   Set<ExtensionBuilder>? _extensionsInScope;
 
+  List<SourceLibraryBuilder>? _patchLibraries;
+
   SourceLibraryBuilder.internal(
       SourceLoader loader,
       Uri fileUri,
       Uri? packageUri,
       LanguageVersion packageLanguageVersion,
       Scope? scope,
-      SourceLibraryBuilder? actualOrigin,
+      SourceLibraryBuilder? origin,
       Library library,
       LibraryBuilder? nameOrigin,
       Library? referencesFrom,
@@ -273,7 +279,7 @@
             packageLanguageVersion,
             new TypeParameterScopeBuilder.library(),
             scope ?? new Scope.top(),
-            actualOrigin,
+            origin,
             library,
             nameOrigin,
             referencesFrom);
@@ -285,7 +291,7 @@
       this.packageLanguageVersion,
       this._libraryTypeParameterScopeBuilder,
       this.importScope,
-      this.actualOrigin,
+      SourceLibraryBuilder? origin,
       this.library,
       this._nameOrigin,
       this.referencesFrom)
@@ -293,6 +299,7 @@
         currentTypeParameterScopeBuilder = _libraryTypeParameterScopeBuilder,
         referencesFromIndexed =
             referencesFrom == null ? null : new IndexedLibrary(referencesFrom),
+        _origin = origin,
         super(fileUri, _libraryTypeParameterScopeBuilder.toScope(importScope),
             new Scope.top()) {
     assert(
@@ -320,6 +327,7 @@
   Version? _enableNamedArgumentsAnywhereVersionInLibrary;
   Version? _enableSuperParametersVersionInLibrary;
   Version? _enableEnhancedEnumsVersionInLibrary;
+  Version? _enableMacrosVersionInLibrary;
   bool? _enableTripleShiftInLibrary;
   bool? _enableExtensionMethodsInLibrary;
   bool? _enableGenericMetadataInLibrary;
@@ -328,6 +336,7 @@
   bool? _enableConstructorTearOffsInLibrary;
   bool? _enableNamedArgumentsAnywhereInLibrary;
   bool? _enableSuperParametersInLibrary;
+  bool? _enableMacrosInLibrary;
 
   bool get enableConstFunctionsInLibrary => _enableConstFunctionsInLibrary ??=
       loader.target.isExperimentEnabledInLibraryByVersion(
@@ -437,6 +446,14 @@
           .getExperimentEnabledVersionInLibrary(
               ExperimentalFlag.enhancedEnums, _packageUri ?? importUri);
 
+  bool get enableMacrosInLibrary => _enableMacrosInLibrary ??= loader.target
+      .isExperimentEnabledInLibraryByVersion(ExperimentalFlag.macros,
+          _packageUri ?? importUri, languageVersion.version);
+
+  Version get enableMacrosVersionInLibrary => _enableMacrosVersionInLibrary ??=
+      loader.target.getExperimentEnabledVersionInLibrary(
+          ExperimentalFlag.macros, _packageUri ?? importUri);
+
   void _updateLibraryNNBDSettings() {
     library.isNonNullableByDefault = isNonNullableByDefault;
     switch (loader.nnbdMode) {
@@ -456,13 +473,13 @@
   }
 
   SourceLibraryBuilder(
-      Uri uri,
-      Uri fileUri,
+      {required Uri importUri,
+      required Uri fileUri,
       Uri? packageUri,
-      LanguageVersion packageLanguageVersion,
-      SourceLoader loader,
-      SourceLibraryBuilder? actualOrigin,
-      {Scope? scope,
+      required LanguageVersion packageLanguageVersion,
+      required SourceLoader loader,
+      SourceLibraryBuilder? origin,
+      Scope? scope,
       Library? target,
       LibraryBuilder? nameOrigin,
       Library? referencesFrom,
@@ -473,10 +490,10 @@
             packageUri,
             packageLanguageVersion,
             scope,
-            actualOrigin,
+            origin,
             target ??
-                (actualOrigin?.library ??
-                    new Library(uri,
+                (origin?.library ??
+                    new Library(importUri,
                         fileUri: fileUri,
                         reference: referenceIsPartOwner == true
                             ? null
@@ -489,6 +506,17 @@
   @override
   bool get isPart => partOfName != null || partOfUri != null;
 
+  // TODO(johnniwinther): Can avoid using this from outside this class?
+  Iterable<SourceLibraryBuilder>? get patchLibraries => _patchLibraries;
+
+  void addPatchLibrary(SourceLibraryBuilder patchLibrary) {
+    assert(patchLibrary.isPatch,
+        "Library ${patchLibrary} must be a patch library.");
+    assert(!patchLibrary.isPart,
+        "Patch library ${patchLibrary} cannot be a part .");
+    (_patchLibraries ??= []).add(patchLibrary);
+  }
+
   List<NamedTypeBuilder> get unresolvedNamedTypes =>
       _libraryTypeParameterScopeBuilder.unresolvedNamedTypes;
 
@@ -720,11 +748,10 @@
         loader.lookupLibraryBuilder(new Uri(scheme: "dart", path: dottedName));
 
     if (imported == null) {
-      LibraryBuilder coreLibrary = loader.read(
-          resolve(this.importUri,
-              new Uri(scheme: "dart", path: "core").toString(), -1),
-          -1,
-          accessorUri: loader.firstUri);
+      LibraryBuilder coreLibrary = loader.readAsEntryPoint(resolve(
+          this.importUri,
+          new Uri(scheme: "dart", path: "core").toString(),
+          -1));
       imported = coreLibrary.loader
           .lookupLibraryBuilder(new Uri(scheme: 'dart', path: dottedName));
     }
@@ -1044,6 +1071,19 @@
 
   /// Builds the core AST structure of this library as needed for the outline.
   Library build(LibraryBuilder coreLibrary, {bool modifyTarget: true}) {
+    // TODO(johnniwinther): Avoid the need to process patch libraries before
+    // the origin. Currently, settings performed by the patch are overridden
+    // by the origin. For instance, the `Map` class is abstract in the origin
+    // but (unintentionally) concrete in the patch. By processing the origin
+    // last the `isAbstract` property set by the patch is corrected by the
+    // origin.
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        patchLibrary.build(coreLibrary, modifyTarget: modifyTarget);
+      }
+    }
+
     checkMemberConflicts(this, scope,
         checkForInstanceVsStaticConflict: false,
         checkForMethodVsSetterConflict: true);
@@ -1290,9 +1330,9 @@
         (library.problemsAsJson ??= <String>[])
             .addAll(part.library.problemsAsJson!);
       }
-      List<FieldBuilder>? partImplicitlyTypedFields =
-          part.takeImplicitlyTypedFields();
-      if (partImplicitlyTypedFields != null) {
+      List<FieldBuilder> partImplicitlyTypedFields = [];
+      part.collectImplicitlyTypedFields(partImplicitlyTypedFields);
+      if (partImplicitlyTypedFields.isNotEmpty) {
         if (_implicitlyTypedFields == null) {
           _implicitlyTypedFields = partImplicitlyTypedFields;
         } else {
@@ -1323,6 +1363,13 @@
   }
 
   void buildInitialScopes() {
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        patchLibrary.buildInitialScopes();
+      }
+    }
+
     NameIterator iterator = nameIterator;
     while (iterator.moveNext()) {
       addToExportScope(iterator.name, iterator.current);
@@ -1330,6 +1377,13 @@
   }
 
   void addImportsToScope() {
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        patchLibrary.addImportsToScope();
+      }
+    }
+
     bool explicitCoreImport = this == loader.coreLibrary;
     for (Import import in imports) {
       if (import.imported?.isPart ?? false) {
@@ -1432,7 +1486,16 @@
   /// Resolves all unresolved types in [unresolvedNamedTypes]. The list of types
   /// is cleared when done.
   int resolveTypes() {
-    int typeCount = unresolvedNamedTypes.length;
+    int typeCount = 0;
+
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        typeCount += patchLibrary.resolveTypes();
+      }
+    }
+
+    typeCount += unresolvedNamedTypes.length;
     for (NamedTypeBuilder namedType in unresolvedNamedTypes) {
       namedType.resolveIn(
           scope, namedType.charOffset!, namedType.fileUri!, this);
@@ -1442,12 +1505,75 @@
     return typeCount;
   }
 
-  @override
-  int resolveConstructors(_) {
-    int count = 0;
+  void installDefaultSupertypes(
+      ClassBuilder objectClassBuilder, Class objectClass) {
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        patchLibrary.installDefaultSupertypes(objectClassBuilder, objectClass);
+      }
+    }
+
     Iterator<Builder> iterator = this.iterator;
     while (iterator.moveNext()) {
-      count += iterator.current.resolveConstructors(this);
+      Builder declaration = iterator.current;
+      if (declaration is SourceClassBuilder) {
+        Class cls = declaration.cls;
+        if (cls != objectClass) {
+          cls.supertype ??= objectClass.asRawSupertype;
+          declaration.supertypeBuilder ??= new NamedTypeBuilder(
+              "Object",
+              const NullabilityBuilder.omitted(),
+              /* arguments = */ null,
+              /* fileUri = */ null,
+              /* charOffset = */ null,
+              instanceTypeVariableAccess:
+                  InstanceTypeVariableAccessState.Unexpected)
+            ..bind(objectClassBuilder);
+        }
+        if (declaration.isMixinApplication) {
+          cls.mixedInType = declaration.mixedInTypeBuilder!.buildMixedInType(
+              this, declaration.charOffset, declaration.fileUri);
+        }
+      }
+    }
+  }
+
+  void collectSourceClasses(List<SourceClassBuilder> sourceClasses) {
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        patchLibrary.collectSourceClasses(sourceClasses);
+      }
+    }
+
+    Iterator<Builder> iterator = this.iterator;
+    while (iterator.moveNext()) {
+      Builder member = iterator.current;
+      if (member is SourceClassBuilder && !member.isPatch) {
+        sourceClasses.add(member);
+      }
+    }
+  }
+
+  /// Resolve constructors (lookup names in scope) recorded in this builder and
+  /// return the number of constructors resolved.
+  int resolveConstructors() {
+    int count = 0;
+
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        count += patchLibrary.resolveConstructors();
+      }
+    }
+
+    Iterator<Builder> iterator = this.iterator;
+    while (iterator.moveNext()) {
+      Builder builder = iterator.current;
+      if (builder is SourceClassBuilder) {
+        count += builder.resolveConstructors(this);
+      }
     }
     return count;
   }
@@ -1490,7 +1616,7 @@
   }
 
   @override
-  SourceLibraryBuilder get origin => actualOrigin ?? this;
+  SourceLibraryBuilder get origin => _origin ?? this;
 
   @override
   Uri get importUri => library.importUri;
@@ -1638,7 +1764,8 @@
       int startOffset,
       int nameOffset,
       int endOffset,
-      int supertypeOffset) {
+      int supertypeOffset,
+      {required bool isMacro}) {
     _addClass(
         TypeParameterScopeKind.classDeclaration,
         metadata,
@@ -1650,7 +1777,8 @@
         startOffset,
         nameOffset,
         endOffset,
-        supertypeOffset);
+        supertypeOffset,
+        isMacro: isMacro);
   }
 
   void addMixinDeclaration(
@@ -1675,7 +1803,8 @@
         startOffset,
         nameOffset,
         endOffset,
-        supertypeOffset);
+        supertypeOffset,
+        isMacro: false);
   }
 
   void _addClass(
@@ -1689,7 +1818,8 @@
       int startOffset,
       int nameOffset,
       int endOffset,
-      int supertypeOffset) {
+      int supertypeOffset,
+      {required bool isMacro}) {
     _checkBadFunctionDeclUse(className, kind, nameOffset);
     _checkBadFunctionParameter(typeVariables);
     // Nested declaration began in `OutlineBuilder.beginClassDeclaration`.
@@ -1727,7 +1857,7 @@
         typeVariables,
         applyMixins(supertype, startOffset, nameOffset, endOffset, className,
             isMixinDeclaration,
-            typeVariables: typeVariables),
+            typeVariables: typeVariables, isMacro: false),
         interfaces,
         // TODO(johnniwinther): Add the `on` clause types of a mixin declaration
         // here.
@@ -1740,7 +1870,8 @@
         nameOffset,
         endOffset,
         _currentClassReferencesFromIndexed,
-        isMixinDeclaration: isMixinDeclaration);
+        isMixinDeclaration: isMixinDeclaration,
+        isMacro: isMacro);
 
     constructorReferences.clear();
     Map<String, TypeVariableBuilder>? typeVariablesByName =
@@ -2000,7 +2131,8 @@
       String? name,
       List<TypeVariableBuilder>? typeVariables,
       int modifiers: 0,
-      List<TypeBuilder>? interfaces}) {
+      List<TypeBuilder>? interfaces,
+      required bool isMacro}) {
     if (name == null) {
       // The following parameters should only be used when building a named
       // mixin application.
@@ -2192,34 +2324,34 @@
         }
 
         SourceClassBuilder application = new SourceClassBuilder(
-          isNamedMixinApplication ? metadata : null,
-          isNamedMixinApplication
-              ? modifiers | namedMixinApplicationMask
-              : abstractMask,
-          fullname,
-          applicationTypeVariables,
-          isMixinDeclaration ? null : supertype,
-          isNamedMixinApplication
-              ? interfaces
-              : isMixinDeclaration
-                  ? [supertype, mixin]
-                  : null,
-          null, // No `on` clause types.
-          new Scope(
-              local: <String, MemberBuilder>{},
-              setters: <String, MemberBuilder>{},
-              parent: scope.withTypeVariables(typeVariables),
-              debugName: "mixin $fullname ",
-              isModifiable: false),
-          new ConstructorScope(fullname, <String, MemberBuilder>{}),
-          this,
-          <ConstructorReferenceBuilder>[],
-          computedStartCharOffset,
-          charOffset,
-          charEndOffset,
-          referencesFromIndexedClass,
-          mixedInTypeBuilder: isMixinDeclaration ? null : mixin,
-        );
+            isNamedMixinApplication ? metadata : null,
+            isNamedMixinApplication
+                ? modifiers | namedMixinApplicationMask
+                : abstractMask,
+            fullname,
+            applicationTypeVariables,
+            isMixinDeclaration ? null : supertype,
+            isNamedMixinApplication
+                ? interfaces
+                : isMixinDeclaration
+                    ? [supertype, mixin]
+                    : null,
+            null, // No `on` clause types.
+            new Scope(
+                local: <String, MemberBuilder>{},
+                setters: <String, MemberBuilder>{},
+                parent: scope.withTypeVariables(typeVariables),
+                debugName: "mixin $fullname ",
+                isModifiable: false),
+            new ConstructorScope(fullname, <String, MemberBuilder>{}),
+            this,
+            <ConstructorReferenceBuilder>[],
+            computedStartCharOffset,
+            charOffset,
+            charEndOffset,
+            referencesFromIndexedClass,
+            mixedInTypeBuilder: isMixinDeclaration ? null : mixin,
+            isMacro: isNamedMixinApplication && isMacro);
         // TODO(ahe, kmillikin): Should always be true?
         // pkg/analyzer/test/src/summary/resynthesize_kernel_test.dart can't
         // handle that :(
@@ -2246,7 +2378,8 @@
       List<TypeBuilder>? interfaces,
       int startCharOffset,
       int charOffset,
-      int charEndOffset) {
+      int charEndOffset,
+      {required bool isMacro}) {
     // Nested declaration began in `OutlineBuilder.beginNamedMixinApplication`.
     endNestedDeclaration(TypeParameterScopeKind.namedMixinApplication, name)
         .resolveNamedTypes(typeVariables, this);
@@ -2256,7 +2389,8 @@
         name: name,
         typeVariables: typeVariables,
         modifiers: modifiers,
-        interfaces: interfaces)!;
+        interfaces: interfaces,
+        isMacro: isMacro)!;
     checkTypeVariables(typeVariables, supertype.declaration);
   }
 
@@ -2770,11 +2904,17 @@
       TypeBuilder? type,
       String name,
       bool hasThis,
+      bool hasSuper,
       int charOffset,
       Token? initializerToken) {
+    assert(!hasThis || !hasSuper,
+        "Formal parameter '${name}' has both 'this' and 'super' prefixes.");
     if (hasThis) {
       modifiers |= initializingFormalMask;
     }
+    if (hasSuper) {
+      modifiers |= superInitializingFormalMask;
+    }
     FormalParameterBuilder formal = new FormalParameterBuilder(
         metadata, modifiers, type, name, this, charOffset,
         fileUri: fileUri)
@@ -2793,10 +2933,45 @@
     return builder;
   }
 
-  @override
-  void buildOutlineExpressions() {
+  void buildOutlineExpressions(
+      CoreTypes coreTypes,
+      List<SynthesizedFunctionNode> synthesizedFunctionNodes,
+      List<DelayedActionPerformer> delayedActionPerformers) {
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        patchLibrary.buildOutlineExpressions(
+            coreTypes, synthesizedFunctionNodes, delayedActionPerformers);
+      }
+    }
+
     MetadataBuilder.buildAnnotations(
         library, metadata, this, null, null, fileUri, scope);
+
+    Iterator<Builder> iterator = this.iterator;
+    while (iterator.moveNext()) {
+      Builder declaration = iterator.current;
+      if (declaration is ClassBuilder) {
+        declaration.buildOutlineExpressions(
+            this, coreTypes, delayedActionPerformers, synthesizedFunctionNodes);
+      } else if (declaration is ExtensionBuilder) {
+        declaration.buildOutlineExpressions(
+            this, coreTypes, delayedActionPerformers, synthesizedFunctionNodes);
+      } else if (declaration is MemberBuilder) {
+        declaration.buildOutlineExpressions(
+            this, coreTypes, delayedActionPerformers, synthesizedFunctionNodes);
+      } else if (declaration is SourceTypeAliasBuilder) {
+        declaration.buildOutlineExpressions(
+            this, coreTypes, delayedActionPerformers, synthesizedFunctionNodes);
+      } else {
+        assert(
+            declaration is PrefixBuilder ||
+                declaration is DynamicTypeDeclarationBuilder ||
+                declaration is NeverTypeDeclarationBuilder,
+            "Unexpected builder in library: ${declaration} "
+            "(${declaration.runtimeType}");
+      }
+    }
   }
 
   /// Builds the core AST structures for [declaration] needed for the outline.
@@ -3009,9 +3184,16 @@
         suppressMessage: false);
   }
 
-  @override
   int finishDeferredLoadTearoffs() {
     int total = 0;
+
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        total += patchLibrary.finishDeferredLoadTearoffs();
+      }
+    }
+
     for (Import import in imports) {
       if (import.deferred) {
         Procedure? tearoff = import.prefixBuilder!.loadLibraryBuilder!.tearoff;
@@ -3021,12 +3203,20 @@
         total++;
       }
     }
+
     return total;
   }
 
-  @override
   int finishForwarders() {
     int count = 0;
+
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        count += patchLibrary.finishForwarders();
+      }
+    }
+
     CloneVisitorNotMembers cloner = new CloneVisitorNotMembers();
     for (int i = 0; i < forwardersOrigins.length; i += 2) {
       Procedure forwarder = forwardersOrigins[i];
@@ -3079,12 +3269,22 @@
     nativeMethods.add(method);
   }
 
-  @override
   int finishNativeMethods() {
+    int count = 0;
+
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        count += patchLibrary.finishNativeMethods();
+      }
+    }
+
     for (FunctionBuilder method in nativeMethods) {
       method.becomeNative(loader);
     }
-    return nativeMethods.length;
+    count += nativeMethods.length;
+
+    return count;
   }
 
   /// Creates a copy of [original] into the scope of [declaration].
@@ -3116,9 +3316,18 @@
     return copy;
   }
 
-  @override
   int finishTypeVariables(ClassBuilder object, TypeBuilder dynamicType) {
-    int count = unboundTypeVariables.length;
+    int count = 0;
+
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        count += patchLibrary.finishTypeVariables(object, dynamicType);
+      }
+    }
+
+    count += unboundTypeVariables.length;
+
     // Ensure that type parameters are built after their dependencies by sorting
     // them topologically using references in bounds.
     for (TypeVariableBuilder builder
@@ -3223,9 +3432,20 @@
     _pendingNullabilities.clear();
   }
 
-  @override
+  /// Computes variances of type parameters on typedefs.
+  ///
+  /// The variance property of type parameters on typedefs is computed from the
+  /// use of the parameters in the right-hand side of the typedef definition.
   int computeVariances() {
     int count = 0;
+
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        count += patchLibrary.computeVariances();
+      }
+    }
+
     for (Builder? declaration
         in _libraryTypeParameterScopeBuilder.members!.values) {
       while (declaration != null) {
@@ -3329,11 +3549,22 @@
     return false;
   }
 
-  @override
+  /// This method instantiates type parameters to their bounds in some cases
+  /// where they were omitted by the programmer and not provided by the type
+  /// inference.  The method returns the number of distinct type variables
+  /// that were instantiated in this library.
   int computeDefaultTypes(TypeBuilder dynamicType, TypeBuilder nullType,
       TypeBuilder bottomType, ClassBuilder objectClass) {
     int count = 0;
 
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        count += patchLibrary.computeDefaultTypes(
+            dynamicType, nullType, bottomType, objectClass);
+      }
+    }
+
     int computeDefaultTypesForVariables(List<TypeVariableBuilder>? variables,
         {required bool inErrorRecovery}) {
       if (variables == null) return 0;
@@ -3553,7 +3784,6 @@
         }
       }
     }
-
     return count;
   }
 
@@ -3621,13 +3851,21 @@
     }
   }
 
-  @override
   int finishPatchMethods() {
-    if (!isPatch) return 0;
     int count = 0;
-    Iterator<Builder> iterator = this.iterator;
-    while (iterator.moveNext()) {
-      count += iterator.current.finishPatch();
+
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        count += patchLibrary.finishPatchMethods();
+      }
+    }
+
+    if (isPatch) {
+      Iterator<Builder> iterator = this.iterator;
+      while (iterator.moveNext()) {
+        count += iterator.current.finishPatch();
+      }
     }
     return count;
   }
@@ -4262,6 +4500,13 @@
   }
 
   void checkTypesInOutline(TypeEnvironment typeEnvironment) {
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        patchLibrary.checkTypesInOutline(typeEnvironment);
+      }
+    }
+
     Iterator<Builder> iterator = this.iterator;
     while (iterator.moveNext()) {
       Builder declaration = iterator.current;
@@ -4294,7 +4539,14 @@
     checkUncheckedTypedefTypes(typeEnvironment);
   }
 
-  void computeShowHideElements(ClassHierarchyBuilder hierarchy) {
+  void computeShowHideElements(ClassMembersBuilder membersBuilder) {
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        patchLibrary.computeShowHideElements(membersBuilder);
+      }
+    }
+
     assert(currentTypeParameterScopeBuilder.kind ==
         TypeParameterScopeKind.library);
     for (SourceExtensionBuilder extensionBuilder
@@ -4306,8 +4558,9 @@
                 new ExtensionTypeShowHideClause();
 
         // TODO(dmitryas): Handle private names.
-        List<Supertype> supertypes =
-            hierarchy.getNodeFromClass(onType.classNode).superclasses;
+        List<Supertype> supertypes = membersBuilder.hierarchyBuilder
+            .getNodeFromClass(onType.classNode)
+            .superclasses;
         Map<String, Supertype> supertypesByName = <String, Supertype>{};
         for (Supertype supertype in supertypes) {
           // TODO(dmitryas): Should only non-generic supertypes be allowed?
@@ -4317,7 +4570,7 @@
         // Handling elements of the 'show' clause.
         for (String memberOrTypeName in extensionBuilder
             .extensionTypeShowHideClauseBuilder.shownMembersOrTypes) {
-          Member? getableMember = hierarchy.getInterfaceMember(
+          Member? getableMember = membersBuilder.getInterfaceMember(
               onType.classNode, new Name(memberOrTypeName));
           if (getableMember != null) {
             if (getableMember is Field) {
@@ -4330,7 +4583,7 @@
               getableMember.kind == ProcedureKind.Method) {
             showHideClause.shownMethods.add(getableMember.reference);
           }
-          Member? setableMember = hierarchy.getInterfaceMember(
+          Member? setableMember = membersBuilder.getInterfaceMember(
               onType.classNode, new Name(memberOrTypeName),
               setter: true);
           if (setableMember != null) {
@@ -4357,7 +4610,7 @@
         }
         for (String getterName in extensionBuilder
             .extensionTypeShowHideClauseBuilder.shownGetters) {
-          Member? member = hierarchy.getInterfaceMember(
+          Member? member = membersBuilder.getInterfaceMember(
               onType.classNode, new Name(getterName));
           if (member != null) {
             if (member is Field) {
@@ -4373,7 +4626,7 @@
         }
         for (String setterName in extensionBuilder
             .extensionTypeShowHideClauseBuilder.shownSetters) {
-          Member? member = hierarchy.getInterfaceMember(
+          Member? member = membersBuilder.getInterfaceMember(
               onType.classNode, new Name(setterName),
               setter: true);
           if (member != null) {
@@ -4394,7 +4647,7 @@
         }
         for (Operator operator in extensionBuilder
             .extensionTypeShowHideClauseBuilder.shownOperators) {
-          Member? member = hierarchy.getInterfaceMember(
+          Member? member = membersBuilder.getInterfaceMember(
               onType.classNode, new Name(operatorToString(operator)));
           if (member != null) {
             showHideClause.shownOperators.add(member.reference);
@@ -4409,7 +4662,7 @@
         // Handling elements of the 'hide' clause.
         for (String memberOrTypeName in extensionBuilder
             .extensionTypeShowHideClauseBuilder.hiddenMembersOrTypes) {
-          Member? getableMember = hierarchy.getInterfaceMember(
+          Member? getableMember = membersBuilder.getInterfaceMember(
               onType.classNode, new Name(memberOrTypeName));
           if (getableMember != null) {
             if (getableMember is Field) {
@@ -4422,7 +4675,7 @@
               getableMember.kind == ProcedureKind.Method) {
             showHideClause.hiddenMethods.add(getableMember.reference);
           }
-          Member? setableMember = hierarchy.getInterfaceMember(
+          Member? setableMember = membersBuilder.getInterfaceMember(
               onType.classNode, new Name(memberOrTypeName),
               setter: true);
           if (setableMember != null) {
@@ -4450,7 +4703,7 @@
         }
         for (String getterName in extensionBuilder
             .extensionTypeShowHideClauseBuilder.hiddenGetters) {
-          Member? member = hierarchy.getInterfaceMember(
+          Member? member = membersBuilder.getInterfaceMember(
               onType.classNode, new Name(getterName));
           if (member != null) {
             if (member is Field) {
@@ -4466,7 +4719,7 @@
         }
         for (String setterName in extensionBuilder
             .extensionTypeShowHideClauseBuilder.hiddenSetters) {
-          Member? member = hierarchy.getInterfaceMember(
+          Member? member = membersBuilder.getInterfaceMember(
               onType.classNode, new Name(setterName),
               setter: true);
           if (member != null) {
@@ -4487,7 +4740,7 @@
         }
         for (Operator operator in extensionBuilder
             .extensionTypeShowHideClauseBuilder.hiddenOperators) {
-          Member? member = hierarchy.getInterfaceMember(
+          Member? member = membersBuilder.getInterfaceMember(
               onType.classNode, new Name(operatorToString(operator)));
           if (member != null) {
             showHideClause.hiddenOperators.add(member.reference);
@@ -4505,11 +4758,19 @@
     (_implicitlyTypedFields ??= <FieldBuilder>[]).add(fieldBuilder);
   }
 
-  @override
-  List<FieldBuilder>? takeImplicitlyTypedFields() {
-    List<FieldBuilder>? result = _implicitlyTypedFields;
-    _implicitlyTypedFields = null;
-    return result;
+  void collectImplicitlyTypedFields(
+      List<FieldBuilder> implicitlyTypedFieldBuilders) {
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        patchLibrary.collectImplicitlyTypedFields(implicitlyTypedFieldBuilders);
+      }
+    }
+
+    if (_implicitlyTypedFields != null) {
+      implicitlyTypedFieldBuilders.addAll(_implicitlyTypedFields!);
+      _implicitlyTypedFields = null;
+    }
   }
 
   void forEachExtensionInScope(void Function(ExtensionBuilder) f) {
@@ -4575,6 +4836,13 @@
   }
 
   void installTypedefTearOffs() {
+    Iterable<SourceLibraryBuilder>? patches = this.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        patchLibrary.installTypedefTearOffs();
+      }
+    }
+
     Iterator<Builder> iterator = this.iterator;
     while (iterator.moveNext()) {
       Builder? declaration = iterator.current;
diff --git a/pkg/front_end/lib/src/fasta/source/source_loader.dart b/pkg/front_end/lib/src/fasta/source/source_loader.dart
index 4043a0a4..2f6b52c 100644
--- a/pkg/front_end/lib/src/fasta/source/source_loader.dart
+++ b/pkg/front_end/lib/src/fasta/source/source_loader.dart
@@ -35,14 +35,12 @@
 import '../../base/common.dart';
 import '../../base/instrumentation.dart' show Instrumentation;
 import '../../base/nnbd_mode.dart';
-import '../dill/dill_class_builder.dart';
 import '../dill/dill_library_builder.dart';
 import '../builder_graph.dart';
 import '../builder/builder.dart';
 import '../builder/class_builder.dart';
 import '../builder/constructor_builder.dart';
 import '../builder/declaration_builder.dart';
-import '../builder/dynamic_type_declaration_builder.dart';
 import '../builder/enum_builder.dart';
 import '../builder/extension_builder.dart';
 import '../builder/field_builder.dart';
@@ -51,8 +49,6 @@
 import '../builder/member_builder.dart';
 import '../builder/modifier_builder.dart';
 import '../builder/named_type_builder.dart';
-import '../builder/never_type_declaration_builder.dart';
-import '../builder/prefix_builder.dart';
 import '../builder/procedure_builder.dart';
 import '../builder/type_alias_builder.dart';
 import '../builder/type_builder.dart';
@@ -63,7 +59,10 @@
 import '../export.dart' show Export;
 import '../fasta_codes.dart';
 import '../kernel/body_builder.dart' show BodyBuilder;
-import '../kernel/class_hierarchy_builder.dart';
+import '../kernel/hierarchy/class_member.dart';
+import '../kernel/hierarchy/delayed.dart';
+import '../kernel/hierarchy/hierarchy_builder.dart';
+import '../kernel/hierarchy/members_builder.dart';
 import '../kernel/kernel_helper.dart'
     show SynthesizedFunctionNode, TypeDependency;
 import '../kernel/kernel_target.dart' show KernelTarget;
@@ -72,7 +71,7 @@
 import '../kernel/transform_set_literals.dart' show SetLiteralTransformer;
 import '../kernel/type_builder_computer.dart' show TypeBuilderComputer;
 import '../loader.dart' show Loader, untranslatableUriScheme;
-import '../problems.dart' show internalProblem, unhandled;
+import '../problems.dart' show internalProblem;
 import '../scope.dart';
 import '../ticker.dart' show Ticker;
 import '../type_inference/type_inference_engine.dart';
@@ -85,11 +84,10 @@
 import 'source_class_builder.dart' show SourceClassBuilder;
 import 'source_library_builder.dart'
     show
-        LanguageVersion,
-        InvalidLanguageVersion,
         ImplicitLanguageVersion,
+        InvalidLanguageVersion,
+        LanguageVersion,
         SourceLibraryBuilder;
-import 'source_type_alias_builder.dart';
 import 'stack_listener_impl.dart' show offsetForToken;
 
 class SourceLoader extends Loader {
@@ -101,7 +99,9 @@
 
   final Map<Uri, List<int>> sourceBytes = <Uri, List<int>>{};
 
-  ClassHierarchyBuilder? _builderHierarchy;
+  ClassHierarchyBuilder? _hierarchyBuilder;
+
+  ClassMembersBuilder? _membersBuilder;
 
   ReferenceFromIndex? referenceFromIndex;
 
@@ -148,6 +148,8 @@
 
   final Map<Uri, LibraryBuilder> _builders = <Uri, LibraryBuilder>{};
 
+  List<SourceLibraryBuilder>? _sourceLibraryBuilders;
+
   final Queue<LibraryBuilder> _unparsedLibraries = new Queue<LibraryBuilder>();
 
   final List<Library> libraries = <Library>[];
@@ -223,12 +225,28 @@
   @override
   LibraryBuilder? lookupLibraryBuilder(Uri importUri) => _builders[importUri];
 
+  /// The [LibraryBuilder]s for libraries built from source or loaded from dill.
+  ///
+  /// Before [resolveParts] have been called, this includes parts and patches.
   Iterable<LibraryBuilder> get libraryBuilders => _builders.values;
 
+  /// The [SourceLibraryBuilder]s for the libraries built from source by this
+  /// source loader.
+  ///
+  /// This is available after [resolveParts] have been called and doesn't
+  /// include parts or patches. Orphaned parts _are_ included.
+  List<SourceLibraryBuilder> get sourceLibraryBuilders {
+    assert(
+        _sourceLibraryBuilders != null,
+        "Source library builder hasn't been computed yet. "
+        "The source libraries are in SourceLoader.resolveParts.");
+    return _sourceLibraryBuilders!;
+  }
+
   Iterable<Uri> get libraryImportUris => _builders.keys;
 
-  void registerLibraryBuilder(LibraryBuilder libraryBuilder, [Uri? uri]) {
-    uri ??= libraryBuilder.importUri;
+  void registerLibraryBuilder(LibraryBuilder libraryBuilder) {
+    Uri uri = libraryBuilder.importUri;
     if (uri.scheme == "dart" && uri.path == "core") {
       _coreLibrary = libraryBuilder;
     }
@@ -248,8 +266,8 @@
 
   Ticker get ticker => target.ticker;
 
-  /// Creates a [SourceLibraryBuilder] corresponding to [uri], if one doesn't
-  /// exist already.
+  /// Creates a [SourceLibraryBuilder] corresponding to [importUri], if one
+  /// doesn't exist already.
   ///
   /// [fileUri] must not be null and is a URI that can be passed to FileSystem
   /// to locate the corresponding file.
@@ -273,15 +291,20 @@
   /// which the library belongs to, or the current sdk version if the library
   /// doesn't belong to a package.
   SourceLibraryBuilder createLibraryBuilder(
-      Uri uri,
-      Uri fileUri,
+      {required Uri importUri,
+      required Uri fileUri,
       Uri? packageUri,
-      LanguageVersion packageLanguageVersion,
+      required LanguageVersion packageLanguageVersion,
       SourceLibraryBuilder? origin,
       Library? referencesFrom,
-      bool? referenceIsPartOwner) {
+      bool? referenceIsPartOwner}) {
     return new SourceLibraryBuilder(
-        uri, fileUri, packageUri, packageLanguageVersion, this, origin,
+        importUri: importUri,
+        fileUri: fileUri,
+        packageUri: packageUri,
+        packageLanguageVersion: packageLanguageVersion,
+        loader: this,
+        origin: origin,
         referencesFrom: referencesFrom,
         referenceIsPartOwner: referenceIsPartOwner);
   }
@@ -365,13 +388,13 @@
         new ImplicitLanguageVersion(target.currentSdkVersion);
 
     SourceLibraryBuilder libraryBuilder = createLibraryBuilder(
-        uri,
-        fileUri,
-        packageUri,
-        packageLanguageVersion,
-        origin,
-        referencesFrom,
-        referenceIsPartOwner);
+        importUri: uri,
+        fileUri: fileUri,
+        packageUri: packageUri,
+        packageLanguageVersion: packageLanguageVersion,
+        origin: origin,
+        referencesFrom: referencesFrom,
+        referenceIsPartOwner: referenceIsPartOwner);
     if (packageLanguageVersionProblem != null) {
       libraryBuilder.addPostponedProblem(
           packageLanguageVersionProblem, 0, noLength, libraryBuilder.fileUri);
@@ -480,8 +503,68 @@
   /// compile-time error.
   LibraryBuilder read(Uri uri, int charOffset,
       {Uri? fileUri,
-      LibraryBuilder? accessor,
-      Uri? accessorUri,
+      required LibraryBuilder accessor,
+      LibraryBuilder? origin,
+      Library? referencesFrom,
+      bool? referenceIsPartOwner}) {
+    LibraryBuilder libraryBuilder = _read(uri,
+        fileUri: fileUri,
+        origin: origin,
+        referencesFrom: referencesFrom,
+        referenceIsPartOwner: referenceIsPartOwner);
+    libraryBuilder.recordAccess(charOffset, noLength, accessor.fileUri);
+    if (!_hasLibraryAccess(imported: uri, importer: accessor.importUri) &&
+        !accessor.isPatch) {
+      accessor.addProblem(messagePlatformPrivateLibraryAccess, charOffset,
+          noLength, accessor.fileUri);
+    }
+    return libraryBuilder;
+  }
+
+  /// Reads the library [uri] as an entry point. This is used for reading the
+  /// entry point library of a script or the explicitly mention libraries of
+  /// a modular or incremental compilation.
+  ///
+  /// This differs from [read] in that there is no accessor library, meaning
+  /// that access to platform private libraries cannot be granted.
+  LibraryBuilder readAsEntryPoint(Uri uri,
+      {Uri? fileUri, Library? referencesFrom}) {
+    LibraryBuilder libraryBuilder =
+        _read(uri, fileUri: fileUri, referencesFrom: referencesFrom);
+    // TODO(johnniwinther): Avoid using the first library, if present, as the
+    // accessor of [libraryBuilder]. Currently the incremental compiler doesn't
+    // handle errors reported without an accessor, since the messages are not
+    // associated with a library. This currently has the side effect that
+    // the first library is the accessor of itself.
+    LibraryBuilder? firstLibrary = first;
+    if (firstLibrary != null) {
+      libraryBuilder.recordAccess(-1, noLength, firstLibrary.fileUri);
+    }
+    if (!_hasLibraryAccess(imported: uri, importer: firstLibrary?.importUri)) {
+      if (firstLibrary != null) {
+        firstLibrary.addProblem(
+            messagePlatformPrivateLibraryAccess, -1, noLength, firstUri);
+      } else {
+        addProblem(messagePlatformPrivateLibraryAccess, -1, noLength, null);
+      }
+    }
+    return libraryBuilder;
+  }
+
+  bool _hasLibraryAccess({required Uri imported, required Uri? importer}) {
+    if (imported.scheme == "dart" && imported.path.startsWith("_")) {
+      if (importer == null) {
+        return false;
+      } else {
+        return target.backendTarget
+            .allowPlatformPrivateLibraryAccess(importer, imported);
+      }
+    }
+    return true;
+  }
+
+  LibraryBuilder _read(Uri uri,
+      {Uri? fileUri,
       LibraryBuilder? origin,
       Library? referencesFrom,
       bool? referenceIsPartOwner}) {
@@ -498,45 +581,27 @@
             referencesFrom,
             referenceIsPartOwner);
       }
-
       _builders[uri] = libraryBuilder;
     }
-    accessor ??= _builders[accessorUri];
-    if (accessor == null) {
-      if (libraryBuilder.loader == this && first != libraryBuilder) {
-        unhandled("null", "accessor", charOffset, uri);
-      }
-    } else {
-      libraryBuilder.recordAccess(charOffset, noLength, accessor.fileUri);
-      if (!accessor.isPatch &&
-          !accessor.isPart &&
-          !target.backendTarget
-              .allowPlatformPrivateLibraryAccess(accessor.importUri, uri)) {
-        accessor.addProblem(messagePlatformPrivateLibraryAccess, charOffset,
-            noLength, accessor.fileUri);
-      }
-    }
     return libraryBuilder;
   }
 
   void _ensureCoreLibrary() {
     if (_coreLibrary == null) {
-      read(Uri.parse("dart:core"), 0, accessorUri: firstUri);
+      readAsEntryPoint(Uri.parse("dart:core"));
       // TODO(askesc): When all backends support set literals, we no longer
       // need to index dart:collection, as it is only needed for desugaring of
       // const sets. We can remove it from this list at that time.
-      read(Uri.parse("dart:collection"), 0, accessorUri: firstUri);
+      readAsEntryPoint(Uri.parse("dart:collection"));
       assert(_coreLibrary != null);
     }
   }
 
   Future<Null> buildBodies() async {
     assert(_coreLibrary != null);
-    for (LibraryBuilder library in libraryBuilders) {
-      if (library.loader == this) {
-        currentUriForCrashReporting = library.importUri;
-        await buildBody(library);
-      }
+    for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+      currentUriForCrashReporting = library.importUri;
+      await buildBody(library);
     }
     currentUriForCrashReporting = null;
     logSummary(templateSourceBodySummary);
@@ -546,7 +611,12 @@
     ticker.log((Duration elapsed, Duration sinceStart) {
       int libraryCount = 0;
       for (LibraryBuilder library in libraryBuilders) {
-        if (library.loader == this) libraryCount++;
+        if (library.loader == this) {
+          libraryCount++;
+          if (library is SourceLibraryBuilder) {
+            libraryCount += library.patchLibraries?.length ?? 0;
+          }
+        }
       }
       double ms = elapsed.inMicroseconds / Duration.microsecondsPerMillisecond;
       Message message = template.withArguments(
@@ -676,7 +746,9 @@
 
   TypeInferenceEngineImpl get typeInferenceEngine => _typeInferenceEngine!;
 
-  ClassHierarchyBuilder get builderHierarchy => _builderHierarchy!;
+  ClassHierarchyBuilder get hierarchyBuilder => _hierarchyBuilder!;
+
+  ClassMembersBuilder get membersBuilder => _membersBuilder!;
 
   Template<SummaryTemplate> get outlineSummaryTemplate =>
       templateSourceOutlineSummary;
@@ -963,29 +1035,34 @@
   }
 
   /// Builds all the method bodies found in the given [library].
-  Future<Null> buildBody(LibraryBuilder library) async {
-    if (library is SourceLibraryBuilder) {
-      // We tokenize source files twice to keep memory usage low. This is the
-      // second time, and the first time was in [buildOutline] above. So this
-      // time we suppress lexical errors.
-      Token tokens = await tokenize(library, suppressLexicalErrors: true);
+  Future<Null> buildBody(SourceLibraryBuilder library) async {
+    Iterable<SourceLibraryBuilder>? patches = library.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        await buildBody(patchLibrary);
+      }
+    }
+
+    // We tokenize source files twice to keep memory usage low. This is the
+    // second time, and the first time was in [buildOutline] above. So this
+    // time we suppress lexical errors.
+    Token tokens = await tokenize(library, suppressLexicalErrors: true);
+    // ignore: unnecessary_null_comparison
+    if (tokens == null) return;
+    DietListener listener = createDietListener(library);
+    DietParser parser = new DietParser(listener);
+    parser.parseUnit(tokens);
+    for (LibraryBuilder part in library.parts) {
+      if (part.partOfLibrary != library) {
+        // Part was included in multiple libraries. Skip it here.
+        continue;
+      }
+      Token tokens = await tokenize(part as SourceLibraryBuilder,
+          suppressLexicalErrors: true);
       // ignore: unnecessary_null_comparison
-      if (tokens == null) return;
-      DietListener listener = createDietListener(library);
-      DietParser parser = new DietParser(listener);
-      parser.parseUnit(tokens);
-      for (LibraryBuilder part in library.parts) {
-        if (part.partOfLibrary != library) {
-          // Part was included in multiple libraries. Skip it here.
-          continue;
-        }
-        Token tokens = await tokenize(part as SourceLibraryBuilder,
-            suppressLexicalErrors: true);
-        // ignore: unnecessary_null_comparison
-        if (tokens != null) {
-          listener.uri = part.fileUri;
-          parser.parseUnit(tokens);
-        }
+      if (tokens != null) {
+        listener.uri = part.fileUri;
+        parser.parseUnit(tokens);
       }
     }
   }
@@ -1061,13 +1138,20 @@
 
   void resolveParts() {
     List<Uri> parts = <Uri>[];
-    List<SourceLibraryBuilder> libraries = <SourceLibraryBuilder>[];
+    List<SourceLibraryBuilder> libraries = [];
+    List<SourceLibraryBuilder> sourceLibraries = [];
+    List<SourceLibraryBuilder> patchLibraries = [];
     _builders.forEach((Uri uri, LibraryBuilder library) {
-      if (library.loader == this) {
+      if (library.loader == this && library is SourceLibraryBuilder) {
         if (library.isPart) {
           parts.add(uri);
         } else {
-          libraries.add(library as SourceLibraryBuilder);
+          if (library.isPatch) {
+            patchLibraries.add(library);
+          } else {
+            sourceLibraries.add(library);
+          }
+          libraries.add(library);
         }
       }
     });
@@ -1086,6 +1170,7 @@
             lookupLibraryBuilder(uri) as SourceLibraryBuilder;
         part.addProblem(messagePartOrphan, 0, 1, part.fileUri);
         part.validatePart(null, null);
+        sourceLibraries.add(part);
       }
     }
     ticker.logMs("Resolved parts");
@@ -1095,6 +1180,25 @@
         library.applyPatches();
       }
     }
+    for (SourceLibraryBuilder patchLibrary in patchLibraries) {
+      _builders.remove(patchLibrary.fileUri);
+      patchLibrary.origin.addPatchLibrary(patchLibrary);
+    }
+    _sourceLibraryBuilders = sourceLibraries;
+    assert(
+        libraryBuilders.every((library) => !library.isPatch),
+        "Patch library found in libraryBuilders: "
+        "${libraryBuilders.where((library) => library.isPatch)}.");
+    assert(
+        sourceLibraries.every((library) => !library.isPatch),
+        "Patch library found in sourceLibraryBuilders: "
+        "${sourceLibraries.where((library) => library.isPatch)}.");
+    assert(
+        libraryBuilders.every((library) =>
+            library.loader != this || sourceLibraries.contains(library)),
+        "Source library not found in sourceLibraryBuilders:"
+        "${libraryBuilders.where((library) => // force line break
+            library.loader == this && !sourceLibraries.contains(library))}");
     ticker.logMs("Applied patches");
   }
 
@@ -1112,6 +1216,19 @@
           exporters.add(exporter.exporter);
         }
       }
+
+      Iterable<SourceLibraryBuilder>? patches =
+          library is SourceLibraryBuilder ? library.patchLibraries : null;
+      if (patches != null) {
+        for (SourceLibraryBuilder patchLibrary in patches) {
+          if (patchLibrary.exporters.isNotEmpty) {
+            exportees.add(patchLibrary);
+            for (Export exporter in patchLibrary.exporters) {
+              exporters.add(exporter.exporter);
+            }
+          }
+        }
+      }
     }
     Set<SourceLibraryBuilder> both = new Set<SourceLibraryBuilder>();
     for (LibraryBuilder exported in exportees) {
@@ -1178,11 +1295,8 @@
 
   void resolveTypes() {
     int typeCount = 0;
-    for (LibraryBuilder library in libraryBuilders) {
-      if (library.loader == this) {
-        SourceLibraryBuilder sourceLibrary = library as SourceLibraryBuilder;
-        typeCount += sourceLibrary.resolveTypes();
-      }
+    for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+      typeCount += library.resolveTypes();
     }
     ticker.logMs("Resolved $typeCount types");
   }
@@ -1209,36 +1323,8 @@
     Set<ClassBuilder> macroClasses = {macroClassBuilder};
     Set<Uri> macroLibraries = {macroLibraryBuilder.importUri};
 
-    bool isMacroClass(TypeDeclarationBuilder? typeDeclarationBuilder) {
-      if (typeDeclarationBuilder == null) return false;
-      while (typeDeclarationBuilder is TypeAliasBuilder) {
-        typeDeclarationBuilder =
-            typeDeclarationBuilder.unaliasDeclaration(null);
-      }
-      if (typeDeclarationBuilder is ClassBuilder) {
-        if (macroClasses.contains(typeDeclarationBuilder)) return true;
-        if (typeDeclarationBuilder is DillClassBuilder) {
-          // TODO(johnniwinther): Recognize macro classes from dill.
-        }
-      }
-      return false;
-    }
-
     for (SourceClassBuilder sourceClassBuilder in sourceClassBuilders) {
-      bool isMacro =
-          isMacroClass(sourceClassBuilder.supertypeBuilder?.declaration);
-      if (!isMacro && sourceClassBuilder.interfaceBuilders != null) {
-        for (TypeBuilder interfaceBuilder
-            in sourceClassBuilder.interfaceBuilders!) {
-          if (isMacroClass(interfaceBuilder.declaration)) {
-            isMacro = true;
-            break;
-          }
-        }
-      }
-      isMacro = isMacro ||
-          isMacroClass(sourceClassBuilder.mixedInTypeBuilder?.declaration);
-      if (isMacro) {
+      if (sourceClassBuilder.isMacro) {
         macroClasses.add(sourceClassBuilder);
         macroLibraries.add(sourceClassBuilder.library.importUri);
         if (retainDataForTesting) {
@@ -1318,8 +1404,8 @@
       return macros.isNotEmpty ? new MacroApplications(macros) : null;
     }
 
-    for (LibraryBuilder libraryBuilder in libraryBuilders) {
-      if (libraryBuilder.loader != this) continue;
+    for (SourceLibraryBuilder libraryBuilder in sourceLibraryBuilders) {
+      // TODO(johnniwinther): Handle patch libraries.
       LibraryMacroApplicationData libraryMacroApplicationData =
           new LibraryMacroApplicationData();
       Library library = libraryBuilder.library;
@@ -1374,60 +1460,48 @@
 
   void finishDeferredLoadTearoffs() {
     int count = 0;
-    for (LibraryBuilder library in libraryBuilders) {
-      if (library.loader == this) {
-        count += library.finishDeferredLoadTearoffs();
-      }
+    for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+      count += library.finishDeferredLoadTearoffs();
     }
     ticker.logMs("Finished deferred load tearoffs $count");
   }
 
   void finishNoSuchMethodForwarders() {
     int count = 0;
-    for (LibraryBuilder library in libraryBuilders) {
-      if (library.loader == this) {
-        count += library.finishForwarders();
-      }
+    for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+      count += library.finishForwarders();
     }
     ticker.logMs("Finished forwarders for $count procedures");
   }
 
   void resolveConstructors() {
     int count = 0;
-    for (LibraryBuilder library in libraryBuilders) {
-      if (library.loader == this) {
-        count += library.resolveConstructors(null);
-      }
+    for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+      count += library.resolveConstructors();
     }
     ticker.logMs("Resolved $count constructors");
   }
 
   void installTypedefTearOffs() {
     if (target.backendTarget.isTypedefTearOffLoweringEnabled) {
-      for (LibraryBuilder library in libraryBuilders) {
-        if (library.loader == this && library is SourceLibraryBuilder) {
-          library.installTypedefTearOffs();
-        }
+      for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+        library.installTypedefTearOffs();
       }
     }
   }
 
   void finishTypeVariables(ClassBuilder object, TypeBuilder dynamicType) {
     int count = 0;
-    for (LibraryBuilder library in libraryBuilders) {
-      if (library.loader == this) {
-        count += library.finishTypeVariables(object, dynamicType);
-      }
+    for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+      count += library.finishTypeVariables(object, dynamicType);
     }
     ticker.logMs("Resolved $count type-variable bounds");
   }
 
   void computeVariances() {
     int count = 0;
-    for (LibraryBuilder library in libraryBuilders) {
-      if (library.loader == this) {
-        count += library.computeVariances();
-      }
+    for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+      count += library.computeVariances();
     }
     ticker.logMs("Computed variances of $count type variables");
   }
@@ -1435,31 +1509,25 @@
   void computeDefaultTypes(TypeBuilder dynamicType, TypeBuilder nullType,
       TypeBuilder bottomType, ClassBuilder objectClass) {
     int count = 0;
-    for (LibraryBuilder library in libraryBuilders) {
-      if (library.loader == this) {
-        count += library.computeDefaultTypes(
-            dynamicType, nullType, bottomType, objectClass);
-      }
+    for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+      count += library.computeDefaultTypes(
+          dynamicType, nullType, bottomType, objectClass);
     }
     ticker.logMs("Computed default types for $count type variables");
   }
 
   void finishNativeMethods() {
     int count = 0;
-    for (LibraryBuilder library in libraryBuilders) {
-      if (library.loader == this) {
-        count += library.finishNativeMethods();
-      }
+    for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+      count += library.finishNativeMethods();
     }
     ticker.logMs("Finished $count native methods");
   }
 
   void finishPatchMethods() {
     int count = 0;
-    for (LibraryBuilder library in libraryBuilders) {
-      if (library.loader == this) {
-        count += library.finishPatchMethods();
-      }
+    for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+      count += library.finishPatchMethods();
     }
     ticker.logMs("Finished $count patch methods");
   }
@@ -1487,6 +1555,15 @@
     }
   }
 
+  /// Returns classes defined in libraries in this [SourceLoader].
+  List<SourceClassBuilder> collectSourceClasses() {
+    List<SourceClassBuilder> sourceClasses = <SourceClassBuilder>[];
+    for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+      library.collectSourceClasses(sourceClasses);
+    }
+    return sourceClasses;
+  }
+
   /// Returns a list of all class builders declared in this loader.  As the
   /// classes are sorted, any cycles in the hierarchy are reported as
   /// errors. Recover by breaking the cycles. This means that the rest of the
@@ -1509,7 +1586,8 @@
     }
 
     // Sort the classes topologically.
-    _SourceClassGraph classGraph = new _SourceClassGraph(this, objectClass);
+    _SourceClassGraph classGraph =
+        new _SourceClassGraph(collectSourceClasses(), objectClass);
     TopologicalSortResult<SourceClassBuilder> result =
         topologicalSort(classGraph);
     List<SourceClassBuilder> classes = result.sortedVertices;
@@ -1654,19 +1732,14 @@
 
   /// Builds the core AST structure needed for the outline of the component.
   void buildComponent() {
-    for (LibraryBuilder library in libraryBuilders) {
-      if (library.loader == this) {
-        SourceLibraryBuilder sourceLibrary = library as SourceLibraryBuilder;
-        Library target = sourceLibrary.build(coreLibrary);
-        if (!library.isPatch) {
-          if (sourceLibrary.referencesFrom != null) {
-            referenceFromIndex ??= new ReferenceFromIndex();
-            referenceFromIndex!.addIndexedLibrary(
-                target, sourceLibrary.referencesFromIndexed!);
-          }
-          libraries.add(target);
-        }
+    for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+      Library target = library.build(coreLibrary);
+      if (library.referencesFrom != null) {
+        referenceFromIndex ??= new ReferenceFromIndex();
+        referenceFromIndex!
+            .addIndexedLibrary(target, library.referencesFromIndexed!);
       }
+      libraries.add(target);
     }
     ticker.logMs("Built component");
   }
@@ -1721,11 +1794,8 @@
   }
 
   void computeShowHideElements() {
-    for (LibraryBuilder libraryBuilder in libraryBuilders) {
-      if (libraryBuilder.loader == this &&
-          libraryBuilder is SourceLibraryBuilder) {
-        libraryBuilder.computeShowHideElements(_builderHierarchy!);
-      }
+    for (SourceLibraryBuilder libraryBuilder in sourceLibraryBuilders) {
+      libraryBuilder.computeShowHideElements(membersBuilder);
     }
     ticker.logMs("Computed show and hide elements");
   }
@@ -1769,21 +1839,16 @@
   }
 
   void checkTypes() {
-    for (LibraryBuilder library in libraryBuilders) {
-      if (library is SourceLibraryBuilder) {
-        if (library.loader == this) {
-          library
-              .checkTypesInOutline(typeInferenceEngine.typeSchemaEnvironment);
-        }
-      }
+    for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+      library.checkTypesInOutline(typeInferenceEngine.typeSchemaEnvironment);
     }
     ticker.logMs("Checked type arguments of supers against the bounds");
   }
 
   void checkOverrides(List<SourceClassBuilder> sourceClasses) {
-    List<DelayedCheck> overrideChecks = builderHierarchy.takeDelayedChecks();
+    List<DelayedCheck> overrideChecks = membersBuilder.takeDelayedChecks();
     for (int i = 0; i < overrideChecks.length; i++) {
-      overrideChecks[i].check(builderHierarchy);
+      overrideChecks[i].check(membersBuilder);
     }
     ticker.logMs("Checked ${overrideChecks.length} overrides");
 
@@ -1793,10 +1858,10 @@
 
   void checkAbstractMembers(List<SourceClassBuilder> sourceClasses) {
     List<ClassMember> delayedMemberChecks =
-        builderHierarchy.takeDelayedMemberComputations();
+        membersBuilder.takeDelayedMemberComputations();
     Set<Class> changedClasses = new Set<Class>();
     for (int i = 0; i < delayedMemberChecks.length; i++) {
-      delayedMemberChecks[i].getMember(builderHierarchy);
+      delayedMemberChecks[i].getMember(membersBuilder);
       changedClasses.add(delayedMemberChecks[i].classBuilder.cls);
     }
     ticker.logMs(
@@ -1850,34 +1915,9 @@
       List<SynthesizedFunctionNode> synthesizedFunctionNodes) {
     List<DelayedActionPerformer> delayedActionPerformers =
         <DelayedActionPerformer>[];
-    for (LibraryBuilder library in libraryBuilders) {
-      if (library.loader == this) {
-        (library as SourceLibraryBuilder).buildOutlineExpressions();
-        Iterator<Builder> iterator = library.iterator;
-        while (iterator.moveNext()) {
-          Builder declaration = iterator.current;
-          if (declaration is ClassBuilder) {
-            declaration.buildOutlineExpressions(library, coreTypes,
-                delayedActionPerformers, synthesizedFunctionNodes);
-          } else if (declaration is ExtensionBuilder) {
-            declaration.buildOutlineExpressions(library, coreTypes,
-                delayedActionPerformers, synthesizedFunctionNodes);
-          } else if (declaration is MemberBuilder) {
-            declaration.buildOutlineExpressions(library, coreTypes,
-                delayedActionPerformers, synthesizedFunctionNodes);
-          } else if (declaration is SourceTypeAliasBuilder) {
-            declaration.buildOutlineExpressions(library, coreTypes,
-                delayedActionPerformers, synthesizedFunctionNodes);
-          } else {
-            assert(
-                declaration is PrefixBuilder ||
-                    declaration is DynamicTypeDeclarationBuilder ||
-                    declaration is NeverTypeDeclarationBuilder,
-                "Unexpected builder in library: ${declaration} "
-                "(${declaration.runtimeType}");
-          }
-        }
-      }
+    for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+      library.buildOutlineExpressions(
+          coreTypes, synthesizedFunctionNodes, delayedActionPerformers);
     }
     for (DelayedActionPerformer delayedActionPerformer
         in delayedActionPerformers) {
@@ -1888,9 +1928,13 @@
 
   void buildClassHierarchy(
       List<SourceClassBuilder> sourceClasses, ClassBuilder objectClass) {
-    _builderHierarchy = ClassHierarchyBuilder.build(
-        objectClass, sourceClasses, this, coreTypes);
-    typeInferenceEngine.hierarchyBuilder = builderHierarchy;
+    ClassHierarchyBuilder hierarchyBuilder = _hierarchyBuilder =
+        ClassHierarchyBuilder.build(
+            objectClass, sourceClasses, this, coreTypes);
+    ClassMembersBuilder membersBuilder = _membersBuilder =
+        ClassMembersBuilder.build(hierarchyBuilder, sourceClasses);
+    typeInferenceEngine.hierarchyBuilder = hierarchyBuilder;
+    typeInferenceEngine.membersBuilder = membersBuilder;
     ticker.logMs("Built class hierarchy");
   }
 
@@ -1904,17 +1948,11 @@
     /// might be subject to type inference, and records dependencies between
     /// them.
     typeInferenceEngine.prepareTopLevel(coreTypes, hierarchy);
-    builderHierarchy.computeTypes();
+    membersBuilder.computeTypes();
 
     List<FieldBuilder> allImplicitlyTypedFields = <FieldBuilder>[];
-    for (LibraryBuilder library in libraryBuilders) {
-      if (library.loader == this) {
-        List<FieldBuilder>? implicitlyTypedFields =
-            library.takeImplicitlyTypedFields();
-        if (implicitlyTypedFields != null) {
-          allImplicitlyTypedFields.addAll(implicitlyTypedFields);
-        }
-      }
+    for (SourceLibraryBuilder library in sourceLibraryBuilders) {
+      library.collectImplicitlyTypedFields(allImplicitlyTypedFields);
     }
 
     for (int i = 0; i < allImplicitlyTypedFields.length; i++) {
@@ -2000,27 +2038,48 @@
         isTopLevel: isTopLevel);
   }
 
-  void checkMainMethods() {
-    DartType? listOfString;
+  void _checkMainMethods(
+      SourceLibraryBuilder libraryBuilder, DartType listOfString) {
+    Iterable<SourceLibraryBuilder>? patches = libraryBuilder.patchLibraries;
+    if (patches != null) {
+      for (SourceLibraryBuilder patchLibrary in patches) {
+        _checkMainMethods(patchLibrary, listOfString);
+      }
+    }
 
-    for (LibraryBuilder libraryBuilder in libraryBuilders) {
-      if (libraryBuilder.loader == this &&
-          libraryBuilder.isNonNullableByDefault) {
-        Builder? mainBuilder =
-            libraryBuilder.exportScope.lookupLocalMember('main', setter: false);
-        mainBuilder ??=
-            libraryBuilder.exportScope.lookupLocalMember('main', setter: true);
-        if (mainBuilder is MemberBuilder) {
-          if (mainBuilder is InvalidTypeDeclarationBuilder) {
-            // This is an ambiguous export, skip the check.
-            return;
+    if (libraryBuilder.isNonNullableByDefault) {
+      Builder? mainBuilder =
+          libraryBuilder.exportScope.lookupLocalMember('main', setter: false);
+      mainBuilder ??=
+          libraryBuilder.exportScope.lookupLocalMember('main', setter: true);
+      if (mainBuilder is MemberBuilder) {
+        if (mainBuilder is InvalidTypeDeclarationBuilder) {
+          // This is an ambiguous export, skip the check.
+          return;
+        }
+        if (mainBuilder.isField ||
+            mainBuilder.isGetter ||
+            mainBuilder.isSetter) {
+          if (mainBuilder.parent != libraryBuilder) {
+            libraryBuilder.addProblem(messageMainNotFunctionDeclarationExported,
+                libraryBuilder.charOffset, noLength, libraryBuilder.fileUri,
+                context: [
+                  messageExportedMain.withLocation(mainBuilder.fileUri!,
+                      mainBuilder.charOffset, mainBuilder.name.length)
+                ]);
+          } else {
+            libraryBuilder.addProblem(
+                messageMainNotFunctionDeclaration,
+                mainBuilder.charOffset,
+                mainBuilder.name.length,
+                mainBuilder.fileUri);
           }
-          if (mainBuilder.isField ||
-              mainBuilder.isGetter ||
-              mainBuilder.isSetter) {
+        } else {
+          Procedure procedure = mainBuilder.member as Procedure;
+          if (procedure.function.requiredParameterCount > 2) {
             if (mainBuilder.parent != libraryBuilder) {
               libraryBuilder.addProblem(
-                  messageMainNotFunctionDeclarationExported,
+                  messageMainTooManyRequiredParametersExported,
                   libraryBuilder.charOffset,
                   noLength,
                   libraryBuilder.fileUri,
@@ -2030,17 +2089,42 @@
                   ]);
             } else {
               libraryBuilder.addProblem(
-                  messageMainNotFunctionDeclaration,
+                  messageMainTooManyRequiredParameters,
                   mainBuilder.charOffset,
                   mainBuilder.name.length,
                   mainBuilder.fileUri);
             }
-          } else {
-            Procedure procedure = mainBuilder.member as Procedure;
-            if (procedure.function.requiredParameterCount > 2) {
+          } else if (procedure.function.namedParameters
+              .any((parameter) => parameter.isRequired)) {
+            if (mainBuilder.parent != libraryBuilder) {
+              libraryBuilder.addProblem(
+                  messageMainRequiredNamedParametersExported,
+                  libraryBuilder.charOffset,
+                  noLength,
+                  libraryBuilder.fileUri,
+                  context: [
+                    messageExportedMain.withLocation(mainBuilder.fileUri!,
+                        mainBuilder.charOffset, mainBuilder.name.length)
+                  ]);
+            } else {
+              libraryBuilder.addProblem(
+                  messageMainRequiredNamedParameters,
+                  mainBuilder.charOffset,
+                  mainBuilder.name.length,
+                  mainBuilder.fileUri);
+            }
+          } else if (procedure.function.positionalParameters.length > 0) {
+            DartType parameterType =
+                procedure.function.positionalParameters.first.type;
+
+            if (!typeEnvironment.isSubtypeOf(listOfString, parameterType,
+                SubtypeCheckMode.withNullabilities)) {
               if (mainBuilder.parent != libraryBuilder) {
                 libraryBuilder.addProblem(
-                    messageMainTooManyRequiredParametersExported,
+                    templateMainWrongParameterTypeExported.withArguments(
+                        parameterType,
+                        listOfString,
+                        libraryBuilder.isNonNullableByDefault),
                     libraryBuilder.charOffset,
                     noLength,
                     libraryBuilder.fileUri,
@@ -2050,87 +2134,44 @@
                     ]);
               } else {
                 libraryBuilder.addProblem(
-                    messageMainTooManyRequiredParameters,
+                    templateMainWrongParameterType.withArguments(parameterType,
+                        listOfString, libraryBuilder.isNonNullableByDefault),
                     mainBuilder.charOffset,
                     mainBuilder.name.length,
                     mainBuilder.fileUri);
               }
-            } else if (procedure.function.namedParameters
-                .any((parameter) => parameter.isRequired)) {
-              if (mainBuilder.parent != libraryBuilder) {
-                libraryBuilder.addProblem(
-                    messageMainRequiredNamedParametersExported,
-                    libraryBuilder.charOffset,
-                    noLength,
-                    libraryBuilder.fileUri,
-                    context: [
-                      messageExportedMain.withLocation(mainBuilder.fileUri!,
-                          mainBuilder.charOffset, mainBuilder.name.length)
-                    ]);
-              } else {
-                libraryBuilder.addProblem(
-                    messageMainRequiredNamedParameters,
-                    mainBuilder.charOffset,
-                    mainBuilder.name.length,
-                    mainBuilder.fileUri);
-              }
-            } else if (procedure.function.positionalParameters.length > 0) {
-              DartType parameterType =
-                  procedure.function.positionalParameters.first.type;
-
-              listOfString ??= new InterfaceType(
-                  coreTypes.listClass,
-                  Nullability.nonNullable,
-                  [coreTypes.stringNonNullableRawType]);
-
-              if (!typeEnvironment.isSubtypeOf(listOfString, parameterType,
-                  SubtypeCheckMode.withNullabilities)) {
-                if (mainBuilder.parent != libraryBuilder) {
-                  libraryBuilder.addProblem(
-                      templateMainWrongParameterTypeExported.withArguments(
-                          parameterType,
-                          listOfString,
-                          libraryBuilder.isNonNullableByDefault),
-                      libraryBuilder.charOffset,
-                      noLength,
-                      libraryBuilder.fileUri,
-                      context: [
-                        messageExportedMain.withLocation(mainBuilder.fileUri!,
-                            mainBuilder.charOffset, mainBuilder.name.length)
-                      ]);
-                } else {
-                  libraryBuilder.addProblem(
-                      templateMainWrongParameterType.withArguments(
-                          parameterType,
-                          listOfString,
-                          libraryBuilder.isNonNullableByDefault),
-                      mainBuilder.charOffset,
-                      mainBuilder.name.length,
-                      mainBuilder.fileUri);
-                }
-              }
             }
           }
-        } else if (mainBuilder != null) {
-          if (mainBuilder.parent != libraryBuilder) {
-            libraryBuilder.addProblem(messageMainNotFunctionDeclarationExported,
-                libraryBuilder.charOffset, noLength, libraryBuilder.fileUri,
-                context: [
-                  messageExportedMain.withLocation(
-                      mainBuilder.fileUri!, mainBuilder.charOffset, noLength)
-                ]);
-          } else {
-            libraryBuilder.addProblem(messageMainNotFunctionDeclaration,
-                mainBuilder.charOffset, noLength, mainBuilder.fileUri);
-          }
+        }
+      } else if (mainBuilder != null) {
+        if (mainBuilder.parent != libraryBuilder) {
+          libraryBuilder.addProblem(messageMainNotFunctionDeclarationExported,
+              libraryBuilder.charOffset, noLength, libraryBuilder.fileUri,
+              context: [
+                messageExportedMain.withLocation(
+                    mainBuilder.fileUri!, mainBuilder.charOffset, noLength)
+              ]);
+        } else {
+          libraryBuilder.addProblem(messageMainNotFunctionDeclaration,
+              mainBuilder.charOffset, noLength, mainBuilder.fileUri);
         }
       }
     }
   }
 
+  void checkMainMethods() {
+    DartType listOfString = new InterfaceType(coreTypes.listClass,
+        Nullability.nonNullable, [coreTypes.stringNonNullableRawType]);
+
+    for (SourceLibraryBuilder libraryBuilder in sourceLibraryBuilders) {
+      _checkMainMethods(libraryBuilder, listOfString);
+    }
+  }
+
   void releaseAncillaryResources() {
     hierarchy = null;
-    _builderHierarchy = null;
+    _hierarchyBuilder = null;
+    _membersBuilder = null;
     _typeInferenceEngine = null;
     _builders.clear();
     libraries.clear();
@@ -2441,26 +2482,13 @@
 
 class _SourceClassGraph implements Graph<SourceClassBuilder> {
   @override
-  final List<SourceClassBuilder> vertices = [];
+  final List<SourceClassBuilder> vertices;
   final ClassBuilder _objectClass;
   final Map<SourceClassBuilder, Map<TypeDeclarationBuilder?, TypeAliasBuilder?>>
       directSupertypeMap = {};
   final Map<SourceClassBuilder, List<SourceClassBuilder>> _supertypeMap = {};
 
-  _SourceClassGraph(SourceLoader loader, this._objectClass) {
-    // Compute the vertices as all classes declared in this loader.
-    for (LibraryBuilder library in loader.libraryBuilders) {
-      if (library.loader == loader) {
-        Iterator<Builder> members = library.iterator;
-        while (members.moveNext()) {
-          Builder member = members.current;
-          if (member is SourceClassBuilder && !member.isPatch) {
-            vertices.add(member);
-          }
-        }
-      }
-    }
-  }
+  _SourceClassGraph(this.vertices, this._objectClass);
 
   List<SourceClassBuilder> computeSuperClasses(SourceClassBuilder cls) {
     Map<TypeDeclarationBuilder?, TypeAliasBuilder?> directSupertypes =
diff --git a/pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.dart b/pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.dart
index 2194bf5..b14927c 100644
--- a/pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.dart
+++ b/pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.dart
@@ -19,7 +19,8 @@
 import '../kernel/forest.dart';
 import '../kernel/implicit_field_type.dart';
 import '../kernel/internal_ast.dart';
-import '../kernel/class_hierarchy_builder.dart' show ClassHierarchyBuilder;
+import '../kernel/hierarchy/hierarchy_builder.dart' show ClassHierarchyBuilder;
+import '../kernel/hierarchy/members_builder.dart' show ClassMembersBuilder;
 import '../kernel/kernel_helper.dart';
 
 import '../source/source_library_builder.dart' show SourceLibraryBuilder;
@@ -103,6 +104,8 @@
 
   late ClassHierarchyBuilder hierarchyBuilder;
 
+  late ClassMembersBuilder membersBuilder;
+
   late CoreTypes coreTypes;
 
   // TODO(johnniwinther): Shared this with the BodyBuilder.
diff --git a/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart b/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart
index 93e1544..5dc515a 100644
--- a/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart
+++ b/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart
@@ -35,7 +35,7 @@
 
 import '../fasta_codes.dart';
 
-import '../kernel/class_hierarchy_builder.dart' show ClassMember;
+import '../kernel/hierarchy/class_member.dart' show ClassMember;
 import '../kernel/constructor_tearoff_lowering.dart';
 import '../kernel/kernel_helper.dart';
 import '../kernel/inference_visitor.dart';
@@ -4250,7 +4250,7 @@
 
   Member? _getInterfaceMember(
       Class class_, Name name, bool setter, int charOffset) {
-    ClassMember? classMember = engine.hierarchyBuilder
+    ClassMember? classMember = engine.membersBuilder
         .getInterfaceClassMember(class_, name, setter: setter);
     if (classMember != null) {
       if (classMember.isStatic) {
@@ -4266,7 +4266,7 @@
         classMember = null;
       }
     }
-    Member? member = classMember?.getMember(engine.hierarchyBuilder);
+    Member? member = classMember?.getMember(engine.membersBuilder);
     if (member == null && library.isPatch) {
       // TODO(johnniwinther): Injected members are currently not included
       // in the class hierarchy builder.
diff --git a/pkg/front_end/lib/src/fasta/util/outline_extractor.dart b/pkg/front_end/lib/src/fasta/util/outline_extractor.dart
index 8caa3f6..ff65e37 100644
--- a/pkg/front_end/lib/src/fasta/util/outline_extractor.dart
+++ b/pkg/front_end/lib/src/fasta/util/outline_extractor.dart
@@ -527,6 +527,7 @@
         }
       }
     }
+    return null;
   }
 }
 
diff --git a/pkg/front_end/lib/src/fasta/util/parser_ast.dart b/pkg/front_end/lib/src/fasta/util/parser_ast.dart
index b648bfc..3b131cf 100644
--- a/pkg/front_end/lib/src/fasta/util/parser_ast.dart
+++ b/pkg/front_end/lib/src/fasta/util/parser_ast.dart
@@ -1137,6 +1137,7 @@
         }
       }
     }
+    return null;
   }
 
   String getImportUriString() {
diff --git a/pkg/front_end/lib/src/fasta/util/parser_ast_helper.dart b/pkg/front_end/lib/src/fasta/util/parser_ast_helper.dart
index 13348fd..d7140cd 100644
--- a/pkg/front_end/lib/src/fasta/util/parser_ast_helper.dart
+++ b/pkg/front_end/lib/src/fasta/util/parser_ast_helper.dart
@@ -165,9 +165,13 @@
   }
 
   @override
-  void beginClassDeclaration(Token begin, Token? abstractToken, Token name) {
+  void beginClassDeclaration(
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {
     ClassDeclarationBegin data = new ClassDeclarationBegin(ParserAstType.BEGIN,
-        begin: begin, abstractToken: abstractToken, name: name);
+        begin: begin,
+        abstractToken: abstractToken,
+        macroToken: macroToken,
+        name: name);
     seen(data);
   }
 
@@ -917,11 +921,12 @@
 
   @override
   void beginNamedMixinApplication(
-      Token begin, Token? abstractToken, Token name) {
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {
     NamedMixinApplicationBegin data = new NamedMixinApplicationBegin(
         ParserAstType.BEGIN,
         begin: begin,
         abstractToken: abstractToken,
+        macroToken: macroToken,
         name: name);
     seen(data);
   }
@@ -2552,13 +2557,20 @@
 
   @override
   void handleCommentReference(
-      Token? newKeyword, Token? prefix, Token? period, Token token) {
+      Token? newKeyword,
+      Token? firstToken,
+      Token? firstPeriod,
+      Token? secondToken,
+      Token? secondPeriod,
+      Token thirdToken) {
     CommentReferenceHandle data = new CommentReferenceHandle(
         ParserAstType.HANDLE,
         newKeyword: newKeyword,
-        prefix: prefix,
-        period: period,
-        token: token);
+        firstToken: firstToken,
+        firstPeriod: firstPeriod,
+        secondToken: secondToken,
+        secondPeriod: secondPeriod,
+        thirdToken: thirdToken);
     seen(data);
   }
 
@@ -2818,16 +2830,21 @@
 class ClassDeclarationBegin extends ParserAstNode {
   final Token begin;
   final Token? abstractToken;
+  final Token? macroToken;
   final Token name;
 
   ClassDeclarationBegin(ParserAstType type,
-      {required this.begin, this.abstractToken, required this.name})
+      {required this.begin,
+      this.abstractToken,
+      this.macroToken,
+      required this.name})
       : super("ClassDeclaration", type);
 
   @override
   Map<String, Object?> get deprecatedArguments => {
         "begin": begin,
         "abstractToken": abstractToken,
+        "macroToken": macroToken,
         "name": name,
       };
 }
@@ -4181,16 +4198,21 @@
 class NamedMixinApplicationBegin extends ParserAstNode {
   final Token begin;
   final Token? abstractToken;
+  final Token? macroToken;
   final Token name;
 
   NamedMixinApplicationBegin(ParserAstType type,
-      {required this.begin, this.abstractToken, required this.name})
+      {required this.begin,
+      this.abstractToken,
+      this.macroToken,
+      required this.name})
       : super("NamedMixinApplication", type);
 
   @override
   Map<String, Object?> get deprecatedArguments => {
         "begin": begin,
         "abstractToken": abstractToken,
+        "macroToken": macroToken,
         "name": name,
       };
 }
@@ -7116,20 +7138,29 @@
 
 class CommentReferenceHandle extends ParserAstNode {
   final Token? newKeyword;
-  final Token? prefix;
-  final Token? period;
-  final Token token;
+  final Token? firstToken;
+  final Token? firstPeriod;
+  final Token? secondToken;
+  final Token? secondPeriod;
+  final Token thirdToken;
 
   CommentReferenceHandle(ParserAstType type,
-      {this.newKeyword, this.prefix, this.period, required this.token})
+      {this.newKeyword,
+      this.firstToken,
+      this.firstPeriod,
+      this.secondToken,
+      this.secondPeriod,
+      required this.thirdToken})
       : super("CommentReference", type);
 
   @override
   Map<String, Object?> get deprecatedArguments => {
         "newKeyword": newKeyword,
-        "prefix": prefix,
-        "period": period,
-        "token": token,
+        "firstToken": firstToken,
+        "firstPeriod": firstPeriod,
+        "secondToken": secondToken,
+        "secondPeriod": secondPeriod,
+        "thirdToken": thirdToken,
       };
 }
 
diff --git a/pkg/front_end/messages.status b/pkg/front_end/messages.status
index c7aca29..10ad152 100644
--- a/pkg/front_end/messages.status
+++ b/pkg/front_end/messages.status
@@ -334,6 +334,8 @@
 FastaUsageLong/example: Fail
 FastaUsageShort/analyzerCode: Fail
 FastaUsageShort/example: Fail
+FfiAbiSpecificIntegerInvalid/analyzerCode: Fail
+FfiAbiSpecificIntegerMappingInvalid/analyzerCode: Fail
 FfiDartTypeMismatch/analyzerCode: Fail
 FfiEmptyStruct/analyzerCode: Fail
 FfiExceptionalReturnNull/analyzerCode: Fail
@@ -725,6 +727,8 @@
 PatchNonExternal/example: Fail
 PlatformPrivateLibraryAccess/example: Fail
 PositionalAfterNamedArgument/example: Fail
+PositionalSuperParametersAndArguments/analyzerCode: Fail
+PositionalSuperParametersAndArguments/example: Fail
 PrefixAfterCombinator/example: Fail
 PreviousUseOfName/analyzerCode: Fail
 PreviousUseOfName/example: Fail
diff --git a/pkg/front_end/messages.yaml b/pkg/front_end/messages.yaml
index 043ebae..6632763 100644
--- a/pkg/front_end/messages.yaml
+++ b/pkg/front_end/messages.yaml
@@ -4554,6 +4554,16 @@
   problemMessage: "This is the instance member."
   severity: CONTEXT
 
+FfiAbiSpecificIntegerInvalid:
+  # Used by dart:ffi
+  problemMessage: "Classes extending 'AbiSpecificInteger' must have exactly one const constructor, no other members, and no type arguments."
+  external: test/ffi_test.dart
+
+FfiAbiSpecificIntegerMappingInvalid:
+  # Used by dart:ffi
+  problemMessage: "Classes extending 'AbiSpecificInteger' must have exactly one 'AbiSpecificIntegerMapping' annotation specifying the mapping from ABI to a NativeType integer with a fixed size."
+  external: test/ffi_test.dart
+
 FfiTypeMismatch:
   # Used by dart:ffi
   problemMessage: "Expected type '#type' to be '#type2', which is the Dart type corresponding to '#type3'."
@@ -5444,3 +5454,10 @@
 EnumDeclaresFactory:
   problemMessage: "Enums can't declare factory constructors."
   correctionMessage: "Try removing the factory constructor declaration."
+
+PositionalSuperParametersAndArguments:
+  problemMessage: "Positional super-initializer parameters cannot be used when the super initializer has positional arguments."
+
+SuperInitializerParameter:
+  problemMessage: "This is the super-initializer parameter."
+  severity: CONTEXT
diff --git a/pkg/front_end/parser_testcases/enhanced_enums/entries_with_type_arguments.dart.intertwined.expect b/pkg/front_end/parser_testcases/enhanced_enums/entries_with_type_arguments.dart.intertwined.expect
index 04b3942..2403c22 100644
--- a/pkg/front_end/parser_testcases/enhanced_enums/entries_with_type_arguments.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/enhanced_enums/entries_with_type_arguments.dart.intertwined.expect
@@ -6,7 +6,7 @@
     parseMetadataStar()
       listener: beginMetadataStar(enum)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, enum, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, enum, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(, enum)
       parseEnum(enum)
         listener: beginUncategorizedTopLevelDeclaration(enum)
diff --git a/pkg/front_end/parser_testcases/error_recovery/bracket_mismatch_01.dart.expect b/pkg/front_end/parser_testcases/error_recovery/bracket_mismatch_01.dart.expect
index 9fc344c..315d899 100644
--- a/pkg/front_end/parser_testcases/error_recovery/bracket_mismatch_01.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/bracket_mismatch_01.dart.expect
@@ -14,7 +14,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -114,7 +114,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(D, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, D)
+    beginClassDeclaration(class, null, null, D)
       handleNoType(D)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/bracket_mismatch_01.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/bracket_mismatch_01.dart.intertwined.expect
index 07f6de4..f075fef 100644
--- a/pkg/front_end/parser_testcases/error_recovery/bracket_mismatch_01.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/bracket_mismatch_01.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
@@ -258,14 +258,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(D, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, D)
+        listener: beginClassDeclaration(class, null, null, D)
         parseClass(D, class, class, D)
           parseClassHeaderOpt(D, class, class)
             parseClassExtendsOpt(D)
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_general.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_general.crash_dart.expect
index acb0f6c..df50087 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_general.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_general.crash_dart.expect
@@ -126,7 +126,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_general.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_general.crash_dart.intertwined.expect
index 88944b7f..06d293d 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_general.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_general.crash_dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_get.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_get.crash_dart.expect
index 4b23187..ddc254b 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_get.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_get.crash_dart.expect
@@ -34,7 +34,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_get.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_get.crash_dart.intertwined.expect
index 75979e4..3f0d02a 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_get.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_get.crash_dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_return_type.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_return_type.crash_dart.expect
index 77c9204..c5b9ca5 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_return_type.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_return_type.crash_dart.expect
@@ -30,7 +30,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_return_type.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_return_type.crash_dart.intertwined.expect
index 7ab4015..510034d 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_return_type.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_return_type.crash_dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_set.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_set.crash_dart.expect
index f2201dc..49cb540 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_set.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_set.crash_dart.expect
@@ -30,7 +30,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_set.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_set.crash_dart.intertwined.expect
index 55c390c..fdc9ae0 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_set.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_bad_name_set.crash_dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_get.dart.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_get.dart.expect
index 4f6c582..affdbb5 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_get.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_get.dart.expect
@@ -30,7 +30,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_get.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_get.dart.intertwined.expect
index 21be0f7..3e8ea041 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_get.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_get.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_ok.dart.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_ok.dart.expect
index 2ed0508..3353b3f 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_ok.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_ok.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_ok.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_ok.dart.intertwined.expect
index 5109bb5..fbd18be 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_ok.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_ok.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_operator.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_operator.crash_dart.expect
index 6b37228..9ecbeda 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_operator.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_operator.crash_dart.expect
@@ -78,7 +78,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_operator.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_operator.crash_dart.intertwined.expect
index e584d14..06cf3f0 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_operator.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_operator.crash_dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_return_type.dart.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_return_type.dart.expect
index 3c0bbca..a93fe07 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_return_type.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_return_type.dart.expect
@@ -22,7 +22,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_return_type.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_return_type.dart.intertwined.expect
index 057bb78..148639d 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_return_type.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_return_type.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_set.dart.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_set.dart.expect
index 1620ea3..e78880d 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_set.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_set.dart.expect
@@ -22,7 +22,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_set.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_set.dart.intertwined.expect
index 5abf42d..d1bd6a8 100644
--- a/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_set.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/constructor_recovery_set.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/error_recovery/extension_member_contributor_test_completion.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/extension_member_contributor_test_completion.dart.intertwined.expect
index 0d4f0e2..c951cb0 100644
--- a/pkg/front_end/parser_testcases/error_recovery/extension_member_contributor_test_completion.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/extension_member_contributor_test_completion.dart.intertwined.expect
@@ -6,7 +6,7 @@
     parseMetadataStar()
       listener: beginMetadataStar(extension)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, extension, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, extension, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(, extension)
       parseExtension(extension)
         listener: beginExtensionDeclarationPrelude(extension)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_000032.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_000032.dart.expect
index 0a96f68..3caae1e 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_000032.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_000032.dart.expect
@@ -26,7 +26,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_000032.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_000032.dart.intertwined.expect
index 0fd3f33..32d89ec 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_000032.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_000032.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_22313.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_22313.dart.expect
index 448b3e0..cfcdd2e 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_22313.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_22313.dart.expect
@@ -26,7 +26,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -41,7 +41,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(B, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, B)
+    beginClassDeclaration(class, null, null, B)
       handleNoType(B)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -56,7 +56,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables(extends)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(,)
       handleType(A, null)
@@ -92,7 +92,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Bar, classOrMixinDeclaration)
     handleNoTypeVariables(extend)
-    beginClassDeclaration(class, null, Bar)
+    beginClassDeclaration(class, null, null, Bar)
       handleNoType(Bar)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -134,7 +134,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Baz, classOrMixinDeclaration)
     handleNoTypeVariables(on)
-    beginClassDeclaration(class, null, Baz)
+    beginClassDeclaration(class, null, null, Baz)
       handleNoType(Baz)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_22313.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_22313.dart.intertwined.expect
index 612efb5..0c27622 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_22313.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_22313.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
@@ -34,14 +34,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(B, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, B)
+        listener: beginClassDeclaration(class, null, null, B)
         parseClass(B, class, class, B)
           parseClassHeaderOpt(B, class, class)
             parseClassExtendsOpt(B)
@@ -62,14 +62,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables(extends)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
@@ -130,14 +130,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Bar, classOrMixinDeclaration)
         listener: handleNoTypeVariables(extend)
-        listener: beginClassDeclaration(class, null, Bar)
+        listener: beginClassDeclaration(class, null, null, Bar)
         parseClass(Bar, class, class, Bar)
           parseClassHeaderOpt(Bar, class, class)
             parseClassExtendsOpt(Bar)
@@ -214,14 +214,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Baz, classOrMixinDeclaration)
         listener: handleNoTypeVariables(on)
-        listener: beginClassDeclaration(class, null, Baz)
+        listener: beginClassDeclaration(class, null, null, Baz)
         parseClass(Baz, class, class, Baz)
           parseClassHeaderOpt(Baz, class, class)
             parseClassExtendsOpt(Baz)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_22314.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_22314.dart.expect
index c95dc3b..50def6f 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_22314.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_22314.dart.expect
@@ -25,7 +25,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Annotation, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Annotation)
+    beginClassDeclaration(class, null, null, Annotation)
       handleNoType(Annotation)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -80,7 +80,7 @@
         handleNoType(E)
       endTypeVariable(>, 0, null, null)
     endTypeVariables(<, >)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(>)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -95,7 +95,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_22314.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_22314.dart.intertwined.expect
index 4720e85..8d39ca9 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_22314.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_22314.dart.intertwined.expect
@@ -28,14 +28,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Annotation, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Annotation)
+        listener: beginClassDeclaration(class, null, null, Annotation)
         parseClass(Annotation, class, class, Annotation)
           parseClassHeaderOpt(Annotation, class, class)
             parseClassExtendsOpt(Annotation)
@@ -112,9 +112,9 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
@@ -127,7 +127,7 @@
         listener: handleNoType(E)
         listener: endTypeVariable(>, 0, null, null)
         listener: endTypeVariables(<, >)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(>, class, class, A)
           parseClassHeaderOpt(>, class, class)
             parseClassExtendsOpt(>)
@@ -148,14 +148,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_26073.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_26073.dart.intertwined.expect
index 0453611..d081a84 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_26073.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_26073.dart.intertwined.expect
@@ -6,7 +6,7 @@
     parseMetadataStar()
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -44,7 +44,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -79,7 +79,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -120,7 +120,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -158,7 +158,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -203,7 +203,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -249,7 +249,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -306,7 +306,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -386,7 +386,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -458,7 +458,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -476,7 +476,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_26810.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_26810.dart.expect
index db84d46..2ac0d92 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_26810.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_26810.dart.expect
@@ -66,7 +66,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
     handleIdentifier(Key, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(abstract, abstract, Key)
+    beginClassDeclaration(abstract, abstract, null, Key)
       handleNoType(Key)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_26810.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_26810.dart.intertwined.expect
index e575bbf..b1c109a 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_26810.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_26810.dart.intertwined.expect
@@ -6,15 +6,15 @@
     parseMetadataStar()
       listener: beginMetadataStar(abstract)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
         parseTopLevelKeywordModifiers(abstract, class)
-      parseClassOrNamedMixinApplication(abstract, class)
+      parseClassOrNamedMixinApplication(abstract, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Key, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(abstract, abstract, Key)
+        listener: beginClassDeclaration(abstract, abstract, null, Key)
         parseClass(Key, abstract, class, Key)
           parseClassHeaderOpt(Key, abstract, class)
             parseClassExtendsOpt(Key)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_26810_and.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_26810_and.dart.expect
index b5464e1..0316b5f 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_26810_and.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_26810_and.dart.expect
@@ -66,7 +66,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
     handleIdentifier(Key, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(abstract, abstract, Key)
+    beginClassDeclaration(abstract, abstract, null, Key)
       handleNoType(Key)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_26810_and.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_26810_and.dart.intertwined.expect
index d50b821..91ece53 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_26810_and.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_26810_and.dart.intertwined.expect
@@ -6,15 +6,15 @@
     parseMetadataStar()
       listener: beginMetadataStar(abstract)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
         parseTopLevelKeywordModifiers(abstract, class)
-      parseClassOrNamedMixinApplication(abstract, class)
+      parseClassOrNamedMixinApplication(abstract, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Key, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(abstract, abstract, Key)
+        listener: beginClassDeclaration(abstract, abstract, null, Key)
         parseClass(Key, abstract, class, Key)
           parseClassHeaderOpt(Key, abstract, class)
             parseClassExtendsOpt(Key)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_26810_or.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_26810_or.dart.expect
index 4f4d844..c5a4273 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_26810_or.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_26810_or.dart.expect
@@ -66,7 +66,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
     handleIdentifier(Key, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(abstract, abstract, Key)
+    beginClassDeclaration(abstract, abstract, null, Key)
       handleNoType(Key)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_26810_or.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_26810_or.dart.intertwined.expect
index 8d04871..f8f7500 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_26810_or.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_26810_or.dart.intertwined.expect
@@ -6,15 +6,15 @@
     parseMetadataStar()
       listener: beginMetadataStar(abstract)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
         parseTopLevelKeywordModifiers(abstract, class)
-      parseClassOrNamedMixinApplication(abstract, class)
+      parseClassOrNamedMixinApplication(abstract, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Key, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(abstract, abstract, Key)
+        listener: beginClassDeclaration(abstract, abstract, null, Key)
         parseClass(Key, abstract, class, Key)
           parseClassHeaderOpt(Key, abstract, class)
             parseClassExtendsOpt(Key)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_39026.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_39026.crash_dart.expect
index e14c1cd..abe79a6 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_39026.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_39026.crash_dart.expect
@@ -14,7 +14,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_39026.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_39026.crash_dart.intertwined.expect
index 885acb8..19f4ce1 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_39026.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_39026.crash_dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_39026_prime.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_39026_prime.crash_dart.expect
index ef39e22..ecd1166 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_39026_prime.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_39026_prime.crash_dart.expect
@@ -10,7 +10,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_39026_prime.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_39026_prime.crash_dart.intertwined.expect
index 8a9a4f4..6329811 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_39026_prime.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_39026_prime.crash_dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_39033.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_39033.crash_dart.intertwined.expect
index 8064bef..8b108c7 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_39033.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_39033.crash_dart.intertwined.expect
@@ -6,7 +6,7 @@
     parseMetadataStar()
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_39230.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_39230.crash_dart.expect
index eb7be0a..e533d5c 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_39230.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_39230.crash_dart.expect
@@ -22,7 +22,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_39230.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_39230.crash_dart.intertwined.expect
index 486d7a3..87cebd9 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_39230.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_39230.crash_dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_41265.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_41265.crash_dart.expect
index 1443cf1..c9eff1a 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_41265.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_41265.crash_dart.expect
@@ -18,7 +18,7 @@
         handleNoType(T)
       endTypeVariable(>, 0, null, null)
     endTypeVariables(<, >)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(>)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -54,7 +54,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(DND1, classOrMixinDeclaration)
     handleNoTypeVariables(extends)
-    beginClassDeclaration(class, null, DND1)
+    beginClassDeclaration(class, null, null, DND1)
       handleIdentifier(Object, typeReference)
       handleNoTypeArguments(with)
       handleType(Object, null)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_41265.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_41265.crash_dart.intertwined.expect
index c046fee..32477fe 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_41265.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_41265.crash_dart.intertwined.expect
@@ -6,9 +6,9 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
@@ -21,7 +21,7 @@
         listener: handleNoType(T)
         listener: endTypeVariable(>, 0, null, null)
         listener: endTypeVariables(<, >)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(>, class, class, A)
           parseClassHeaderOpt(>, class, class)
             parseClassExtendsOpt(>)
@@ -42,7 +42,7 @@
     parseMetadataStar(})
       listener: beginMetadataStar(mixin)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, mixin, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, mixin, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(}, mixin)
       parseMixin(mixin)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(mixin)
@@ -74,14 +74,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(DND1, classOrMixinDeclaration)
         listener: handleNoTypeVariables(extends)
-        listener: beginClassDeclaration(class, null, DND1)
+        listener: beginClassDeclaration(class, null, null, DND1)
         parseClass(DND1, class, class, DND1)
           parseClassHeaderOpt(DND1, class, class)
             parseClassExtendsOpt(DND1)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_43090.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_43090.crash_dart.intertwined.expect
index 1fc743a..fdef824 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_43090.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_43090.crash_dart.intertwined.expect
@@ -6,7 +6,7 @@
     parseMetadataStar()
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_43090_prime_01.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_43090_prime_01.crash_dart.intertwined.expect
index 2c656d6..4c19f5b 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_43090_prime_01.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_43090_prime_01.crash_dart.intertwined.expect
@@ -6,7 +6,7 @@
     parseMetadataStar()
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_43090_prime_02.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_43090_prime_02.crash_dart.intertwined.expect
index 2845e0b..b8f453d 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_43090_prime_02.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_43090_prime_02.crash_dart.intertwined.expect
@@ -6,7 +6,7 @@
     parseMetadataStar()
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251.dart.expect
index d370a1f..9a36032 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251.dart.expect
@@ -22,7 +22,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(F, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, F)
+    beginClassDeclaration(class, null, null, F)
       handleNoType(F)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251.dart.intertwined.expect
index 487b2f4..46c74ad 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(F, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, F)
+        listener: beginClassDeclaration(class, null, null, F)
         parseClass(F, class, class, F)
           parseClassHeaderOpt(F, class, class)
             parseClassExtendsOpt(F)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_const.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_const.dart.expect
index 3e6acd8..548af9c 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_const.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_const.dart.expect
@@ -22,7 +22,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(F, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, F)
+    beginClassDeclaration(class, null, null, F)
       handleNoType(F)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_const.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_const.dart.intertwined.expect
index 3286fb7..04648ed 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_const.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_const.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(F, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, F)
+        listener: beginClassDeclaration(class, null, null, F)
         parseClass(F, class, class, F)
           parseClassHeaderOpt(F, class, class)
             parseClassExtendsOpt(F)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_list.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_list.dart.expect
index a77c1d4..fc0194c 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_list.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_list.dart.expect
@@ -18,7 +18,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(F, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, F)
+    beginClassDeclaration(class, null, null, F)
       handleNoType(F)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_list.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_list.dart.intertwined.expect
index 78e2879..78a0d51 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_list.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_list.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(F, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, F)
+        listener: beginClassDeclaration(class, null, null, F)
         parseClass(F, class, class, F)
           parseClassHeaderOpt(F, class, class)
             parseClassExtendsOpt(F)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_const.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_const.dart.expect
index 7671fc4..143a90d 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_const.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_const.dart.expect
@@ -22,7 +22,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(F, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, F)
+    beginClassDeclaration(class, null, null, F)
       handleNoType(F)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_const.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_const.dart.intertwined.expect
index 1859b0b..5602483 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_const.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_const.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(F, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, F)
+        listener: beginClassDeclaration(class, null, null, F)
         parseClass(F, class, class, F)
           parseClassHeaderOpt(F, class, class)
             parseClassExtendsOpt(F)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_new.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_new.dart.expect
index 1711905..9792fa7 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_new.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_new.dart.expect
@@ -34,7 +34,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(F, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, F)
+    beginClassDeclaration(class, null, null, F)
       handleNoType(F)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_new.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_new.dart.intertwined.expect
index 4a37dea..eba032d 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_new.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_list_new.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(F, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, F)
+        listener: beginClassDeclaration(class, null, null, F)
         parseClass(F, class, class, F)
           parseClassHeaderOpt(F, class, class)
             parseClassExtendsOpt(F)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_new.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_new.dart.expect
index b2a0a36..88ac7ed 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_new.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_new.dart.expect
@@ -34,7 +34,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(F, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, F)
+    beginClassDeclaration(class, null, null, F)
       handleNoType(F)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_new.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_new.dart.intertwined.expect
index 77176c4..ccc11a0 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_new.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_new.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(F, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, F)
+        listener: beginClassDeclaration(class, null, null, F)
         parseClass(F, class, class, F)
           parseClassHeaderOpt(F, class, class)
             parseClassExtendsOpt(F)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_set.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_set.dart.expect
index 48a989a..9138896 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_set.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_set.dart.expect
@@ -22,7 +22,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(F, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, F)
+    beginClassDeclaration(class, null, null, F)
       handleNoType(F)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_set.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_set.dart.intertwined.expect
index 4c25c0e..498b48a 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_set.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_set.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(F, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, F)
+        listener: beginClassDeclaration(class, null, null, F)
         parseClass(F, class, class, F)
           parseClassHeaderOpt(F, class, class)
             parseClassExtendsOpt(F)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_const.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_const.dart.expect
index e64026f..a2bf1e5 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_const.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_const.dart.expect
@@ -22,7 +22,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(F, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, F)
+    beginClassDeclaration(class, null, null, F)
       handleNoType(F)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_const.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_const.dart.intertwined.expect
index 2b0b373..b2e7f3e 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_const.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_const.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(F, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, F)
+        listener: beginClassDeclaration(class, null, null, F)
         parseClass(F, class, class, F)
           parseClassHeaderOpt(F, class, class)
             parseClassExtendsOpt(F)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_new.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_new.dart.expect
index cf0c95b..a62bd2c 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_new.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_new.dart.expect
@@ -34,7 +34,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(F, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, F)
+    beginClassDeclaration(class, null, null, F)
       handleNoType(F)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_new.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_new.dart.intertwined.expect
index 642c608..dabdaef 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_new.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45251_set_new.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(F, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, F)
+        listener: beginClassDeclaration(class, null, null, F)
         parseClass(F, class, class, F)
           parseClassHeaderOpt(F, class, class)
             parseClassExtendsOpt(F)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45327_prime_1.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45327_prime_1.crash_dart.expect
index 51b616e..aaf3524 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45327_prime_1.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45327_prime_1.crash_dart.expect
@@ -22,7 +22,7 @@
         handleNoType(T)
       endTypeVariable(>, 0, null, null)
     endTypeVariables(<, >)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(>)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_45327_prime_1.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_45327_prime_1.crash_dart.intertwined.expect
index 352b89d..4cba827 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_45327_prime_1.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_45327_prime_1.crash_dart.intertwined.expect
@@ -6,9 +6,9 @@
     parseMetadataStar(UnmatchedToken(())
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(UnmatchedToken((), class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(UnmatchedToken((), class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(UnmatchedToken((), class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
@@ -21,7 +21,7 @@
         listener: handleNoType(T)
         listener: endTypeVariable(>, 0, null, null)
         listener: endTypeVariables(<, >)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(>, class, class, Foo)
           parseClassHeaderOpt(>, class, class)
             parseClassExtendsOpt(>)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46346.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46346.dart.expect
index 1819758..3bc1986 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46346.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46346.dart.expect
@@ -227,7 +227,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'abstract' as a name here., null, {lexeme: abstract}], abstract, abstract)
     handleIdentifier(abstract, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, abstract)
+    beginClassDeclaration(class, null, null, abstract)
       handleNoType(abstract)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -243,7 +243,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'as' as a name here., null, {lexeme: as}], as, as)
     handleIdentifier(as, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, as)
+    beginClassDeclaration(class, null, null, as)
       handleNoType(as)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -259,7 +259,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'assert' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: assert}], assert, assert)
     handleIdentifier(assert, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, assert)
+    beginClassDeclaration(class, null, null, assert)
       handleNoType(assert)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -274,7 +274,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(async, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, async)
+    beginClassDeclaration(class, null, null, async)
       handleNoType(async)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -289,7 +289,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(await, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, await)
+    beginClassDeclaration(class, null, null, await)
       handleNoType(await)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -305,7 +305,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'break' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: break}], break, break)
     handleIdentifier(break, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, break)
+    beginClassDeclaration(class, null, null, break)
       handleNoType(break)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -321,7 +321,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'case' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: case}], case, case)
     handleIdentifier(case, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, case)
+    beginClassDeclaration(class, null, null, case)
       handleNoType(case)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -337,7 +337,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'catch' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: catch}], catch, catch)
     handleIdentifier(catch, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, catch)
+    beginClassDeclaration(class, null, null, catch)
       handleNoType(catch)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -353,7 +353,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'class' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: class}], class, class)
     handleIdentifier(class, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, class)
+    beginClassDeclaration(class, null, null, class)
       handleNoType(class)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -369,7 +369,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'const' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: const}], const, const)
     handleIdentifier(const, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, const)
+    beginClassDeclaration(class, null, null, const)
       handleNoType(const)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -385,7 +385,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'continue' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: continue}], continue, continue)
     handleIdentifier(continue, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, continue)
+    beginClassDeclaration(class, null, null, continue)
       handleNoType(continue)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -401,7 +401,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'covariant' as a name here., null, {lexeme: covariant}], covariant, covariant)
     handleIdentifier(covariant, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, covariant)
+    beginClassDeclaration(class, null, null, covariant)
       handleNoType(covariant)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -417,7 +417,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'default' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: default}], default, default)
     handleIdentifier(default, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, default)
+    beginClassDeclaration(class, null, null, default)
       handleNoType(default)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -433,7 +433,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'deferred' as a name here., null, {lexeme: deferred}], deferred, deferred)
     handleIdentifier(deferred, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, deferred)
+    beginClassDeclaration(class, null, null, deferred)
       handleNoType(deferred)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -449,7 +449,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'do' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: do}], do, do)
     handleIdentifier(do, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, do)
+    beginClassDeclaration(class, null, null, do)
       handleNoType(do)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -465,7 +465,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'dynamic' as a name here., null, {lexeme: dynamic}], dynamic, dynamic)
     handleIdentifier(dynamic, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, dynamic)
+    beginClassDeclaration(class, null, null, dynamic)
       handleNoType(dynamic)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -481,7 +481,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'else' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: else}], else, else)
     handleIdentifier(else, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, else)
+    beginClassDeclaration(class, null, null, else)
       handleNoType(else)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -497,7 +497,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'enum' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: enum}], enum, enum)
     handleIdentifier(enum, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, enum)
+    beginClassDeclaration(class, null, null, enum)
       handleNoType(enum)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -513,7 +513,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'export' as a name here., null, {lexeme: export}], export, export)
     handleIdentifier(export, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, export)
+    beginClassDeclaration(class, null, null, export)
       handleNoType(export)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -529,7 +529,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'extends' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: extends}], extends, extends)
     handleIdentifier(extends, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, extends)
+    beginClassDeclaration(class, null, null, extends)
       handleNoType(extends)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -545,7 +545,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'extension' as a name here., null, {lexeme: extension}], extension, extension)
     handleIdentifier(extension, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, extension)
+    beginClassDeclaration(class, null, null, extension)
       handleNoType(extension)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -561,7 +561,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'external' as a name here., null, {lexeme: external}], external, external)
     handleIdentifier(external, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, external)
+    beginClassDeclaration(class, null, null, external)
       handleNoType(external)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -577,7 +577,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'factory' as a name here., null, {lexeme: factory}], factory, factory)
     handleIdentifier(factory, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, factory)
+    beginClassDeclaration(class, null, null, factory)
       handleNoType(factory)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -593,7 +593,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'false' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: false}], false, false)
     handleIdentifier(false, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, false)
+    beginClassDeclaration(class, null, null, false)
       handleNoType(false)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -609,7 +609,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'final' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: final}], final, final)
     handleIdentifier(final, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, final)
+    beginClassDeclaration(class, null, null, final)
       handleNoType(final)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -625,7 +625,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'finally' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: finally}], finally, finally)
     handleIdentifier(finally, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, finally)
+    beginClassDeclaration(class, null, null, finally)
       handleNoType(finally)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -641,7 +641,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'for' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: for}], for, for)
     handleIdentifier(for, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, for)
+    beginClassDeclaration(class, null, null, for)
       handleNoType(for)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -656,7 +656,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Function, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Function)
+    beginClassDeclaration(class, null, null, Function)
       handleNoType(Function)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -672,7 +672,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'get' as a name here., null, {lexeme: get}], get, get)
     handleIdentifier(get, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, get)
+    beginClassDeclaration(class, null, null, get)
       handleNoType(get)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -687,7 +687,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(hide, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, hide)
+    beginClassDeclaration(class, null, null, hide)
       handleNoType(hide)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -703,7 +703,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'if' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: if}], if, if)
     handleIdentifier(if, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, if)
+    beginClassDeclaration(class, null, null, if)
       handleNoType(if)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -719,7 +719,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'implements' as a name here., null, {lexeme: implements}], implements, implements)
     handleIdentifier(implements, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, implements)
+    beginClassDeclaration(class, null, null, implements)
       handleNoType(implements)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -735,7 +735,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'import' as a name here., null, {lexeme: import}], import, import)
     handleIdentifier(import, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, import)
+    beginClassDeclaration(class, null, null, import)
       handleNoType(import)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -751,7 +751,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'in' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: in}], in, in)
     handleIdentifier(in, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, in)
+    beginClassDeclaration(class, null, null, in)
       handleNoType(in)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -766,7 +766,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(inout, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, inout)
+    beginClassDeclaration(class, null, null, inout)
       handleNoType(inout)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -782,7 +782,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'interface' as a name here., null, {lexeme: interface}], interface, interface)
     handleIdentifier(interface, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, interface)
+    beginClassDeclaration(class, null, null, interface)
       handleNoType(interface)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -798,7 +798,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'is' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: is}], is, is)
     handleIdentifier(is, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, is)
+    beginClassDeclaration(class, null, null, is)
       handleNoType(is)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -814,7 +814,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'late' as a name here., null, {lexeme: late}], late, late)
     handleIdentifier(late, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, late)
+    beginClassDeclaration(class, null, null, late)
       handleNoType(late)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -830,7 +830,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'library' as a name here., null, {lexeme: library}], library, library)
     handleIdentifier(library, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, library)
+    beginClassDeclaration(class, null, null, library)
       handleNoType(library)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -846,7 +846,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'mixin' as a name here., null, {lexeme: mixin}], mixin, mixin)
     handleIdentifier(mixin, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, mixin)
+    beginClassDeclaration(class, null, null, mixin)
       handleNoType(mixin)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -861,7 +861,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(native, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, native)
+    beginClassDeclaration(class, null, null, native)
       handleNoType(native)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -877,7 +877,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'new' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: new}], new, new)
     handleIdentifier(new, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, new)
+    beginClassDeclaration(class, null, null, new)
       handleNoType(new)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -893,7 +893,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'null' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: null}], null, null)
     handleIdentifier(null, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, null)
+    beginClassDeclaration(class, null, null, null)
       handleNoType(null)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -908,7 +908,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(of, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, of)
+    beginClassDeclaration(class, null, null, of)
       handleNoType(of)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -923,7 +923,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(on, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, on)
+    beginClassDeclaration(class, null, null, on)
       handleNoType(on)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -939,7 +939,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'operator' as a name here., null, {lexeme: operator}], operator, operator)
     handleIdentifier(operator, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, operator)
+    beginClassDeclaration(class, null, null, operator)
       handleNoType(operator)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -954,7 +954,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(out, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, out)
+    beginClassDeclaration(class, null, null, out)
       handleNoType(out)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -970,7 +970,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'part' as a name here., null, {lexeme: part}], part, part)
     handleIdentifier(part, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, part)
+    beginClassDeclaration(class, null, null, part)
       handleNoType(part)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -985,7 +985,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(patch, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, patch)
+    beginClassDeclaration(class, null, null, patch)
       handleNoType(patch)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1001,7 +1001,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'required' as a name here., null, {lexeme: required}], required, required)
     handleIdentifier(required, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, required)
+    beginClassDeclaration(class, null, null, required)
       handleNoType(required)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1017,7 +1017,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'rethrow' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: rethrow}], rethrow, rethrow)
     handleIdentifier(rethrow, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, rethrow)
+    beginClassDeclaration(class, null, null, rethrow)
       handleNoType(rethrow)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1033,7 +1033,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'return' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: return}], return, return)
     handleIdentifier(return, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, return)
+    beginClassDeclaration(class, null, null, return)
       handleNoType(return)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1049,7 +1049,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'set' as a name here., null, {lexeme: set}], set, set)
     handleIdentifier(set, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, set)
+    beginClassDeclaration(class, null, null, set)
       handleNoType(set)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1064,7 +1064,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(show, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, show)
+    beginClassDeclaration(class, null, null, show)
       handleNoType(show)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1079,7 +1079,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(source, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, source)
+    beginClassDeclaration(class, null, null, source)
       handleNoType(source)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1095,7 +1095,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'static' as a name here., null, {lexeme: static}], static, static)
     handleIdentifier(static, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, static)
+    beginClassDeclaration(class, null, null, static)
       handleNoType(static)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1111,7 +1111,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'super' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: super}], super, super)
     handleIdentifier(super, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, super)
+    beginClassDeclaration(class, null, null, super)
       handleNoType(super)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1127,7 +1127,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'switch' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: switch}], switch, switch)
     handleIdentifier(switch, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, switch)
+    beginClassDeclaration(class, null, null, switch)
       handleNoType(switch)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1142,7 +1142,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(sync, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, sync)
+    beginClassDeclaration(class, null, null, sync)
       handleNoType(sync)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1158,7 +1158,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'this' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: this}], this, this)
     handleIdentifier(this, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, this)
+    beginClassDeclaration(class, null, null, this)
       handleNoType(this)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1174,7 +1174,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'throw' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: throw}], throw, throw)
     handleIdentifier(throw, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, throw)
+    beginClassDeclaration(class, null, null, throw)
       handleNoType(throw)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1190,7 +1190,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'true' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: true}], true, true)
     handleIdentifier(true, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, true)
+    beginClassDeclaration(class, null, null, true)
       handleNoType(true)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1206,7 +1206,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'try' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: try}], try, try)
     handleIdentifier(try, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, try)
+    beginClassDeclaration(class, null, null, try)
       handleNoType(try)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1222,7 +1222,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'typedef' as a name here., null, {lexeme: typedef}], typedef, typedef)
     handleIdentifier(typedef, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, typedef)
+    beginClassDeclaration(class, null, null, typedef)
       handleNoType(typedef)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1238,7 +1238,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'var' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: var}], var, var)
     handleIdentifier(var, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, var)
+    beginClassDeclaration(class, null, null, var)
       handleNoType(var)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1254,7 +1254,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'void' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: void}], void, void)
     handleIdentifier(void, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, void)
+    beginClassDeclaration(class, null, null, void)
       handleNoType(void)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1270,7 +1270,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'while' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: while}], while, while)
     handleIdentifier(while, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, while)
+    beginClassDeclaration(class, null, null, while)
       handleNoType(while)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1286,7 +1286,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'with' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: with}], with, with)
     handleIdentifier(with, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, with)
+    beginClassDeclaration(class, null, null, with)
       handleNoType(with)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -1301,7 +1301,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(yield, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, yield)
+    beginClassDeclaration(class, null, null, yield)
       handleNoType(yield)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46346.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46346.dart.intertwined.expect
index 5a31b41..6c9c866 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46346.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46346.dart.intertwined.expect
@@ -6,16 +6,16 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(abstract, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'abstract' as a name here., null, {lexeme: abstract}], abstract, abstract)
           listener: handleIdentifier(abstract, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, abstract)
+        listener: beginClassDeclaration(class, null, null, abstract)
         parseClass(abstract, class, class, abstract)
           parseClassHeaderOpt(abstract, class, class)
             parseClassExtendsOpt(abstract)
@@ -36,16 +36,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(as, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'as' as a name here., null, {lexeme: as}], as, as)
           listener: handleIdentifier(as, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, as)
+        listener: beginClassDeclaration(class, null, null, as)
         parseClass(as, class, class, as)
           parseClassHeaderOpt(as, class, class)
             parseClassExtendsOpt(as)
@@ -66,16 +66,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(assert, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'assert' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: assert}], assert, assert)
           listener: handleIdentifier(assert, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, assert)
+        listener: beginClassDeclaration(class, null, null, assert)
         parseClass(assert, class, class, assert)
           parseClassHeaderOpt(assert, class, class)
             parseClassExtendsOpt(assert)
@@ -96,14 +96,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(async, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, async)
+        listener: beginClassDeclaration(class, null, null, async)
         parseClass(async, class, class, async)
           parseClassHeaderOpt(async, class, class)
             parseClassExtendsOpt(async)
@@ -124,14 +124,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(await, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, await)
+        listener: beginClassDeclaration(class, null, null, await)
         parseClass(await, class, class, await)
           parseClassHeaderOpt(await, class, class)
             parseClassExtendsOpt(await)
@@ -152,16 +152,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(break, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'break' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: break}], break, break)
           listener: handleIdentifier(break, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, break)
+        listener: beginClassDeclaration(class, null, null, break)
         parseClass(break, class, class, break)
           parseClassHeaderOpt(break, class, class)
             parseClassExtendsOpt(break)
@@ -182,16 +182,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(case, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'case' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: case}], case, case)
           listener: handleIdentifier(case, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, case)
+        listener: beginClassDeclaration(class, null, null, case)
         parseClass(case, class, class, case)
           parseClassHeaderOpt(case, class, class)
             parseClassExtendsOpt(case)
@@ -212,16 +212,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(catch, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'catch' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: catch}], catch, catch)
           listener: handleIdentifier(catch, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, catch)
+        listener: beginClassDeclaration(class, null, null, catch)
         parseClass(catch, class, class, catch)
           parseClassHeaderOpt(catch, class, class)
             parseClassExtendsOpt(catch)
@@ -242,16 +242,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(class, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'class' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: class}], class, class)
           listener: handleIdentifier(class, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, class)
+        listener: beginClassDeclaration(class, null, null, class)
         parseClass(class, class, class, class)
           parseClassHeaderOpt(class, class, class)
             parseClassExtendsOpt(class)
@@ -272,16 +272,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(const, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'const' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: const}], const, const)
           listener: handleIdentifier(const, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, const)
+        listener: beginClassDeclaration(class, null, null, const)
         parseClass(const, class, class, const)
           parseClassHeaderOpt(const, class, class)
             parseClassExtendsOpt(const)
@@ -302,16 +302,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(continue, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'continue' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: continue}], continue, continue)
           listener: handleIdentifier(continue, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, continue)
+        listener: beginClassDeclaration(class, null, null, continue)
         parseClass(continue, class, class, continue)
           parseClassHeaderOpt(continue, class, class)
             parseClassExtendsOpt(continue)
@@ -332,16 +332,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(covariant, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'covariant' as a name here., null, {lexeme: covariant}], covariant, covariant)
           listener: handleIdentifier(covariant, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, covariant)
+        listener: beginClassDeclaration(class, null, null, covariant)
         parseClass(covariant, class, class, covariant)
           parseClassHeaderOpt(covariant, class, class)
             parseClassExtendsOpt(covariant)
@@ -362,16 +362,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(default, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'default' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: default}], default, default)
           listener: handleIdentifier(default, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, default)
+        listener: beginClassDeclaration(class, null, null, default)
         parseClass(default, class, class, default)
           parseClassHeaderOpt(default, class, class)
             parseClassExtendsOpt(default)
@@ -392,16 +392,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(deferred, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'deferred' as a name here., null, {lexeme: deferred}], deferred, deferred)
           listener: handleIdentifier(deferred, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, deferred)
+        listener: beginClassDeclaration(class, null, null, deferred)
         parseClass(deferred, class, class, deferred)
           parseClassHeaderOpt(deferred, class, class)
             parseClassExtendsOpt(deferred)
@@ -422,16 +422,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(do, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'do' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: do}], do, do)
           listener: handleIdentifier(do, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, do)
+        listener: beginClassDeclaration(class, null, null, do)
         parseClass(do, class, class, do)
           parseClassHeaderOpt(do, class, class)
             parseClassExtendsOpt(do)
@@ -452,16 +452,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(dynamic, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'dynamic' as a name here., null, {lexeme: dynamic}], dynamic, dynamic)
           listener: handleIdentifier(dynamic, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, dynamic)
+        listener: beginClassDeclaration(class, null, null, dynamic)
         parseClass(dynamic, class, class, dynamic)
           parseClassHeaderOpt(dynamic, class, class)
             parseClassExtendsOpt(dynamic)
@@ -482,16 +482,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(else, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'else' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: else}], else, else)
           listener: handleIdentifier(else, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, else)
+        listener: beginClassDeclaration(class, null, null, else)
         parseClass(else, class, class, else)
           parseClassHeaderOpt(else, class, class)
             parseClassExtendsOpt(else)
@@ -512,16 +512,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(enum, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'enum' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: enum}], enum, enum)
           listener: handleIdentifier(enum, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, enum)
+        listener: beginClassDeclaration(class, null, null, enum)
         parseClass(enum, class, class, enum)
           parseClassHeaderOpt(enum, class, class)
             parseClassExtendsOpt(enum)
@@ -542,16 +542,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(export, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'export' as a name here., null, {lexeme: export}], export, export)
           listener: handleIdentifier(export, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, export)
+        listener: beginClassDeclaration(class, null, null, export)
         parseClass(export, class, class, export)
           parseClassHeaderOpt(export, class, class)
             parseClassExtendsOpt(export)
@@ -572,16 +572,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(extends, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'extends' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: extends}], extends, extends)
           listener: handleIdentifier(extends, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, extends)
+        listener: beginClassDeclaration(class, null, null, extends)
         parseClass(extends, class, class, extends)
           parseClassHeaderOpt(extends, class, class)
             parseClassExtendsOpt(extends)
@@ -602,16 +602,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(extension, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'extension' as a name here., null, {lexeme: extension}], extension, extension)
           listener: handleIdentifier(extension, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, extension)
+        listener: beginClassDeclaration(class, null, null, extension)
         parseClass(extension, class, class, extension)
           parseClassHeaderOpt(extension, class, class)
             parseClassExtendsOpt(extension)
@@ -632,16 +632,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(external, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'external' as a name here., null, {lexeme: external}], external, external)
           listener: handleIdentifier(external, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, external)
+        listener: beginClassDeclaration(class, null, null, external)
         parseClass(external, class, class, external)
           parseClassHeaderOpt(external, class, class)
             parseClassExtendsOpt(external)
@@ -662,16 +662,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(factory, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'factory' as a name here., null, {lexeme: factory}], factory, factory)
           listener: handleIdentifier(factory, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, factory)
+        listener: beginClassDeclaration(class, null, null, factory)
         parseClass(factory, class, class, factory)
           parseClassHeaderOpt(factory, class, class)
             parseClassExtendsOpt(factory)
@@ -692,16 +692,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(false, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'false' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: false}], false, false)
           listener: handleIdentifier(false, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, false)
+        listener: beginClassDeclaration(class, null, null, false)
         parseClass(false, class, class, false)
           parseClassHeaderOpt(false, class, class)
             parseClassExtendsOpt(false)
@@ -722,16 +722,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(final, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'final' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: final}], final, final)
           listener: handleIdentifier(final, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, final)
+        listener: beginClassDeclaration(class, null, null, final)
         parseClass(final, class, class, final)
           parseClassHeaderOpt(final, class, class)
             parseClassExtendsOpt(final)
@@ -752,16 +752,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(finally, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'finally' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: finally}], finally, finally)
           listener: handleIdentifier(finally, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, finally)
+        listener: beginClassDeclaration(class, null, null, finally)
         parseClass(finally, class, class, finally)
           parseClassHeaderOpt(finally, class, class)
             parseClassExtendsOpt(finally)
@@ -782,16 +782,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(for, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'for' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: for}], for, for)
           listener: handleIdentifier(for, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, for)
+        listener: beginClassDeclaration(class, null, null, for)
         parseClass(for, class, class, for)
           parseClassHeaderOpt(for, class, class)
             parseClassExtendsOpt(for)
@@ -812,14 +812,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Function, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Function)
+        listener: beginClassDeclaration(class, null, null, Function)
         parseClass(Function, class, class, Function)
           parseClassHeaderOpt(Function, class, class)
             parseClassExtendsOpt(Function)
@@ -840,16 +840,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(get, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'get' as a name here., null, {lexeme: get}], get, get)
           listener: handleIdentifier(get, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, get)
+        listener: beginClassDeclaration(class, null, null, get)
         parseClass(get, class, class, get)
           parseClassHeaderOpt(get, class, class)
             parseClassExtendsOpt(get)
@@ -870,14 +870,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(hide, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, hide)
+        listener: beginClassDeclaration(class, null, null, hide)
         parseClass(hide, class, class, hide)
           parseClassHeaderOpt(hide, class, class)
             parseClassExtendsOpt(hide)
@@ -898,16 +898,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(if, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'if' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: if}], if, if)
           listener: handleIdentifier(if, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, if)
+        listener: beginClassDeclaration(class, null, null, if)
         parseClass(if, class, class, if)
           parseClassHeaderOpt(if, class, class)
             parseClassExtendsOpt(if)
@@ -928,16 +928,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(implements, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'implements' as a name here., null, {lexeme: implements}], implements, implements)
           listener: handleIdentifier(implements, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, implements)
+        listener: beginClassDeclaration(class, null, null, implements)
         parseClass(implements, class, class, implements)
           parseClassHeaderOpt(implements, class, class)
             parseClassExtendsOpt(implements)
@@ -958,16 +958,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(import, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'import' as a name here., null, {lexeme: import}], import, import)
           listener: handleIdentifier(import, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, import)
+        listener: beginClassDeclaration(class, null, null, import)
         parseClass(import, class, class, import)
           parseClassHeaderOpt(import, class, class)
             parseClassExtendsOpt(import)
@@ -988,16 +988,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(in, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'in' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: in}], in, in)
           listener: handleIdentifier(in, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, in)
+        listener: beginClassDeclaration(class, null, null, in)
         parseClass(in, class, class, in)
           parseClassHeaderOpt(in, class, class)
             parseClassExtendsOpt(in)
@@ -1018,14 +1018,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(inout, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, inout)
+        listener: beginClassDeclaration(class, null, null, inout)
         parseClass(inout, class, class, inout)
           parseClassHeaderOpt(inout, class, class)
             parseClassExtendsOpt(inout)
@@ -1046,16 +1046,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(interface, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'interface' as a name here., null, {lexeme: interface}], interface, interface)
           listener: handleIdentifier(interface, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, interface)
+        listener: beginClassDeclaration(class, null, null, interface)
         parseClass(interface, class, class, interface)
           parseClassHeaderOpt(interface, class, class)
             parseClassExtendsOpt(interface)
@@ -1076,16 +1076,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(is, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'is' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: is}], is, is)
           listener: handleIdentifier(is, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, is)
+        listener: beginClassDeclaration(class, null, null, is)
         parseClass(is, class, class, is)
           parseClassHeaderOpt(is, class, class)
             parseClassExtendsOpt(is)
@@ -1106,16 +1106,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(late, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'late' as a name here., null, {lexeme: late}], late, late)
           listener: handleIdentifier(late, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, late)
+        listener: beginClassDeclaration(class, null, null, late)
         parseClass(late, class, class, late)
           parseClassHeaderOpt(late, class, class)
             parseClassExtendsOpt(late)
@@ -1136,16 +1136,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(library, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'library' as a name here., null, {lexeme: library}], library, library)
           listener: handleIdentifier(library, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, library)
+        listener: beginClassDeclaration(class, null, null, library)
         parseClass(library, class, class, library)
           parseClassHeaderOpt(library, class, class)
             parseClassExtendsOpt(library)
@@ -1166,16 +1166,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(mixin, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'mixin' as a name here., null, {lexeme: mixin}], mixin, mixin)
           listener: handleIdentifier(mixin, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, mixin)
+        listener: beginClassDeclaration(class, null, null, mixin)
         parseClass(mixin, class, class, mixin)
           parseClassHeaderOpt(mixin, class, class)
             parseClassExtendsOpt(mixin)
@@ -1196,14 +1196,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(native, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, native)
+        listener: beginClassDeclaration(class, null, null, native)
         parseClass(native, class, class, native)
           parseClassHeaderOpt(native, class, class)
             parseClassExtendsOpt(native)
@@ -1224,16 +1224,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(new, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'new' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: new}], new, new)
           listener: handleIdentifier(new, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, new)
+        listener: beginClassDeclaration(class, null, null, new)
         parseClass(new, class, class, new)
           parseClassHeaderOpt(new, class, class)
             parseClassExtendsOpt(new)
@@ -1254,16 +1254,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(null, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'null' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: null}], null, null)
           listener: handleIdentifier(null, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, null)
+        listener: beginClassDeclaration(class, null, null, null)
         parseClass(null, class, class, null)
           parseClassHeaderOpt(null, class, class)
             parseClassExtendsOpt(null)
@@ -1284,14 +1284,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(of, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, of)
+        listener: beginClassDeclaration(class, null, null, of)
         parseClass(of, class, class, of)
           parseClassHeaderOpt(of, class, class)
             parseClassExtendsOpt(of)
@@ -1312,14 +1312,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(on, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, on)
+        listener: beginClassDeclaration(class, null, null, on)
         parseClass(on, class, class, on)
           parseClassHeaderOpt(on, class, class)
             parseClassExtendsOpt(on)
@@ -1340,16 +1340,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(operator, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'operator' as a name here., null, {lexeme: operator}], operator, operator)
           listener: handleIdentifier(operator, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, operator)
+        listener: beginClassDeclaration(class, null, null, operator)
         parseClass(operator, class, class, operator)
           parseClassHeaderOpt(operator, class, class)
             parseClassExtendsOpt(operator)
@@ -1370,14 +1370,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(out, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, out)
+        listener: beginClassDeclaration(class, null, null, out)
         parseClass(out, class, class, out)
           parseClassHeaderOpt(out, class, class)
             parseClassExtendsOpt(out)
@@ -1398,16 +1398,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(part, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'part' as a name here., null, {lexeme: part}], part, part)
           listener: handleIdentifier(part, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, part)
+        listener: beginClassDeclaration(class, null, null, part)
         parseClass(part, class, class, part)
           parseClassHeaderOpt(part, class, class)
             parseClassExtendsOpt(part)
@@ -1428,14 +1428,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(patch, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, patch)
+        listener: beginClassDeclaration(class, null, null, patch)
         parseClass(patch, class, class, patch)
           parseClassHeaderOpt(patch, class, class)
             parseClassExtendsOpt(patch)
@@ -1456,16 +1456,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(required, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'required' as a name here., null, {lexeme: required}], required, required)
           listener: handleIdentifier(required, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, required)
+        listener: beginClassDeclaration(class, null, null, required)
         parseClass(required, class, class, required)
           parseClassHeaderOpt(required, class, class)
             parseClassExtendsOpt(required)
@@ -1486,16 +1486,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(rethrow, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'rethrow' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: rethrow}], rethrow, rethrow)
           listener: handleIdentifier(rethrow, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, rethrow)
+        listener: beginClassDeclaration(class, null, null, rethrow)
         parseClass(rethrow, class, class, rethrow)
           parseClassHeaderOpt(rethrow, class, class)
             parseClassExtendsOpt(rethrow)
@@ -1516,16 +1516,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(return, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'return' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: return}], return, return)
           listener: handleIdentifier(return, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, return)
+        listener: beginClassDeclaration(class, null, null, return)
         parseClass(return, class, class, return)
           parseClassHeaderOpt(return, class, class)
             parseClassExtendsOpt(return)
@@ -1546,16 +1546,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(set, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'set' as a name here., null, {lexeme: set}], set, set)
           listener: handleIdentifier(set, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, set)
+        listener: beginClassDeclaration(class, null, null, set)
         parseClass(set, class, class, set)
           parseClassHeaderOpt(set, class, class)
             parseClassExtendsOpt(set)
@@ -1576,14 +1576,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(show, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, show)
+        listener: beginClassDeclaration(class, null, null, show)
         parseClass(show, class, class, show)
           parseClassHeaderOpt(show, class, class)
             parseClassExtendsOpt(show)
@@ -1604,14 +1604,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(source, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, source)
+        listener: beginClassDeclaration(class, null, null, source)
         parseClass(source, class, class, source)
           parseClassHeaderOpt(source, class, class)
             parseClassExtendsOpt(source)
@@ -1632,16 +1632,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(static, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'static' as a name here., null, {lexeme: static}], static, static)
           listener: handleIdentifier(static, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, static)
+        listener: beginClassDeclaration(class, null, null, static)
         parseClass(static, class, class, static)
           parseClassHeaderOpt(static, class, class)
             parseClassExtendsOpt(static)
@@ -1662,16 +1662,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(super, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'super' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: super}], super, super)
           listener: handleIdentifier(super, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, super)
+        listener: beginClassDeclaration(class, null, null, super)
         parseClass(super, class, class, super)
           parseClassHeaderOpt(super, class, class)
             parseClassExtendsOpt(super)
@@ -1692,16 +1692,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(switch, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'switch' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: switch}], switch, switch)
           listener: handleIdentifier(switch, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, switch)
+        listener: beginClassDeclaration(class, null, null, switch)
         parseClass(switch, class, class, switch)
           parseClassHeaderOpt(switch, class, class)
             parseClassExtendsOpt(switch)
@@ -1722,14 +1722,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(sync, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, sync)
+        listener: beginClassDeclaration(class, null, null, sync)
         parseClass(sync, class, class, sync)
           parseClassHeaderOpt(sync, class, class)
             parseClassExtendsOpt(sync)
@@ -1750,16 +1750,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(this, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'this' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: this}], this, this)
           listener: handleIdentifier(this, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, this)
+        listener: beginClassDeclaration(class, null, null, this)
         parseClass(this, class, class, this)
           parseClassHeaderOpt(this, class, class)
             parseClassExtendsOpt(this)
@@ -1780,16 +1780,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(throw, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'throw' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: throw}], throw, throw)
           listener: handleIdentifier(throw, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, throw)
+        listener: beginClassDeclaration(class, null, null, throw)
         parseClass(throw, class, class, throw)
           parseClassHeaderOpt(throw, class, class)
             parseClassExtendsOpt(throw)
@@ -1810,16 +1810,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(true, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'true' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: true}], true, true)
           listener: handleIdentifier(true, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, true)
+        listener: beginClassDeclaration(class, null, null, true)
         parseClass(true, class, class, true)
           parseClassHeaderOpt(true, class, class)
             parseClassExtendsOpt(true)
@@ -1840,16 +1840,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(try, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'try' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: try}], try, try)
           listener: handleIdentifier(try, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, try)
+        listener: beginClassDeclaration(class, null, null, try)
         parseClass(try, class, class, try)
           parseClassHeaderOpt(try, class, class)
             parseClassExtendsOpt(try)
@@ -1870,16 +1870,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(typedef, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'typedef' as a name here., null, {lexeme: typedef}], typedef, typedef)
           listener: handleIdentifier(typedef, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, typedef)
+        listener: beginClassDeclaration(class, null, null, typedef)
         parseClass(typedef, class, class, typedef)
           parseClassHeaderOpt(typedef, class, class)
             parseClassExtendsOpt(typedef)
@@ -1900,16 +1900,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(var, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'var' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: var}], var, var)
           listener: handleIdentifier(var, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, var)
+        listener: beginClassDeclaration(class, null, null, var)
         parseClass(var, class, class, var)
           parseClassHeaderOpt(var, class, class)
             parseClassExtendsOpt(var)
@@ -1930,16 +1930,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(void, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'void' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: void}], void, void)
           listener: handleIdentifier(void, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, void)
+        listener: beginClassDeclaration(class, null, null, void)
         parseClass(void, class, class, void)
           parseClassHeaderOpt(void, class, class)
             parseClassExtendsOpt(void)
@@ -1960,16 +1960,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(while, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'while' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: while}], while, while)
           listener: handleIdentifier(while, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, while)
+        listener: beginClassDeclaration(class, null, null, while)
         parseClass(while, class, class, while)
           parseClassHeaderOpt(while, class, class)
             parseClassExtendsOpt(while)
@@ -1990,16 +1990,16 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(with, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'with' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: with}], with, with)
           listener: handleIdentifier(with, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, with)
+        listener: beginClassDeclaration(class, null, null, with)
         parseClass(with, class, class, with)
           parseClassHeaderOpt(with, class, class)
             parseClassExtendsOpt(with)
@@ -2020,14 +2020,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(yield, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, yield)
+        listener: beginClassDeclaration(class, null, null, yield)
         parseClass(yield, class, class, yield)
           parseClassHeaderOpt(yield, class, class)
             parseClassExtendsOpt(yield)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_1.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_1.dart.expect
index ddf5505..b29582c 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_1.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_1.dart.expect
@@ -227,7 +227,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'abstract' as a name here., null, {lexeme: abstract}], abstract, abstract)
     handleIdentifier(abstract, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, abstract)
+    beginNamedMixinApplication(class, null, null, abstract)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -245,7 +245,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'as' as a name here., null, {lexeme: as}], as, as)
     handleIdentifier(as, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, as)
+    beginNamedMixinApplication(class, null, null, as)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -263,7 +263,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'assert' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: assert}], assert, assert)
     handleIdentifier(assert, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, assert)
+    beginNamedMixinApplication(class, null, null, assert)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -280,7 +280,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(async, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, async)
+    beginNamedMixinApplication(class, null, null, async)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -297,7 +297,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(await, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, await)
+    beginNamedMixinApplication(class, null, null, await)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -315,7 +315,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'break' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: break}], break, break)
     handleIdentifier(break, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, break)
+    beginNamedMixinApplication(class, null, null, break)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -333,7 +333,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'case' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: case}], case, case)
     handleIdentifier(case, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, case)
+    beginNamedMixinApplication(class, null, null, case)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -351,7 +351,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'catch' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: catch}], catch, catch)
     handleIdentifier(catch, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, catch)
+    beginNamedMixinApplication(class, null, null, catch)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -369,7 +369,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'class' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: class}], class, class)
     handleIdentifier(class, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, class)
+    beginNamedMixinApplication(class, null, null, class)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -387,7 +387,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'const' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: const}], const, const)
     handleIdentifier(const, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, const)
+    beginNamedMixinApplication(class, null, null, const)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -405,7 +405,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'continue' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: continue}], continue, continue)
     handleIdentifier(continue, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, continue)
+    beginNamedMixinApplication(class, null, null, continue)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -423,7 +423,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'covariant' as a name here., null, {lexeme: covariant}], covariant, covariant)
     handleIdentifier(covariant, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, covariant)
+    beginNamedMixinApplication(class, null, null, covariant)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -441,7 +441,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'default' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: default}], default, default)
     handleIdentifier(default, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, default)
+    beginNamedMixinApplication(class, null, null, default)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -459,7 +459,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'deferred' as a name here., null, {lexeme: deferred}], deferred, deferred)
     handleIdentifier(deferred, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, deferred)
+    beginNamedMixinApplication(class, null, null, deferred)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -477,7 +477,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'do' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: do}], do, do)
     handleIdentifier(do, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, do)
+    beginNamedMixinApplication(class, null, null, do)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -495,7 +495,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'dynamic' as a name here., null, {lexeme: dynamic}], dynamic, dynamic)
     handleIdentifier(dynamic, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, dynamic)
+    beginNamedMixinApplication(class, null, null, dynamic)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -513,7 +513,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'else' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: else}], else, else)
     handleIdentifier(else, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, else)
+    beginNamedMixinApplication(class, null, null, else)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -531,7 +531,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'enum' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: enum}], enum, enum)
     handleIdentifier(enum, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, enum)
+    beginNamedMixinApplication(class, null, null, enum)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -549,7 +549,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'export' as a name here., null, {lexeme: export}], export, export)
     handleIdentifier(export, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, export)
+    beginNamedMixinApplication(class, null, null, export)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -567,7 +567,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'extends' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: extends}], extends, extends)
     handleIdentifier(extends, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, extends)
+    beginNamedMixinApplication(class, null, null, extends)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -585,7 +585,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'extension' as a name here., null, {lexeme: extension}], extension, extension)
     handleIdentifier(extension, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, extension)
+    beginNamedMixinApplication(class, null, null, extension)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -603,7 +603,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'external' as a name here., null, {lexeme: external}], external, external)
     handleIdentifier(external, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, external)
+    beginNamedMixinApplication(class, null, null, external)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -621,7 +621,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'factory' as a name here., null, {lexeme: factory}], factory, factory)
     handleIdentifier(factory, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, factory)
+    beginNamedMixinApplication(class, null, null, factory)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -639,7 +639,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'false' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: false}], false, false)
     handleIdentifier(false, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, false)
+    beginNamedMixinApplication(class, null, null, false)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -657,7 +657,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'final' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: final}], final, final)
     handleIdentifier(final, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, final)
+    beginNamedMixinApplication(class, null, null, final)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -675,7 +675,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'finally' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: finally}], finally, finally)
     handleIdentifier(finally, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, finally)
+    beginNamedMixinApplication(class, null, null, finally)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -693,7 +693,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'for' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: for}], for, for)
     handleIdentifier(for, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, for)
+    beginNamedMixinApplication(class, null, null, for)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -710,7 +710,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Function, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, Function)
+    beginNamedMixinApplication(class, null, null, Function)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -728,7 +728,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'get' as a name here., null, {lexeme: get}], get, get)
     handleIdentifier(get, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, get)
+    beginNamedMixinApplication(class, null, null, get)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -745,7 +745,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(hide, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, hide)
+    beginNamedMixinApplication(class, null, null, hide)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -763,7 +763,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'if' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: if}], if, if)
     handleIdentifier(if, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, if)
+    beginNamedMixinApplication(class, null, null, if)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -781,7 +781,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'implements' as a name here., null, {lexeme: implements}], implements, implements)
     handleIdentifier(implements, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, implements)
+    beginNamedMixinApplication(class, null, null, implements)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -799,7 +799,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'import' as a name here., null, {lexeme: import}], import, import)
     handleIdentifier(import, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, import)
+    beginNamedMixinApplication(class, null, null, import)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -817,7 +817,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'in' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: in}], in, in)
     handleIdentifier(in, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, in)
+    beginNamedMixinApplication(class, null, null, in)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -834,7 +834,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(inout, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, inout)
+    beginNamedMixinApplication(class, null, null, inout)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -852,7 +852,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'interface' as a name here., null, {lexeme: interface}], interface, interface)
     handleIdentifier(interface, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, interface)
+    beginNamedMixinApplication(class, null, null, interface)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -870,7 +870,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'is' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: is}], is, is)
     handleIdentifier(is, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, is)
+    beginNamedMixinApplication(class, null, null, is)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -888,7 +888,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'late' as a name here., null, {lexeme: late}], late, late)
     handleIdentifier(late, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, late)
+    beginNamedMixinApplication(class, null, null, late)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -906,7 +906,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'library' as a name here., null, {lexeme: library}], library, library)
     handleIdentifier(library, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, library)
+    beginNamedMixinApplication(class, null, null, library)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -924,7 +924,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'mixin' as a name here., null, {lexeme: mixin}], mixin, mixin)
     handleIdentifier(mixin, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, mixin)
+    beginNamedMixinApplication(class, null, null, mixin)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -941,7 +941,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(native, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, native)
+    beginNamedMixinApplication(class, null, null, native)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -959,7 +959,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'new' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: new}], new, new)
     handleIdentifier(new, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, new)
+    beginNamedMixinApplication(class, null, null, new)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -977,7 +977,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'null' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: null}], null, null)
     handleIdentifier(null, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, null)
+    beginNamedMixinApplication(class, null, null, null)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -994,7 +994,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(of, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, of)
+    beginNamedMixinApplication(class, null, null, of)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1011,7 +1011,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(on, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, on)
+    beginNamedMixinApplication(class, null, null, on)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1029,7 +1029,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'operator' as a name here., null, {lexeme: operator}], operator, operator)
     handleIdentifier(operator, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, operator)
+    beginNamedMixinApplication(class, null, null, operator)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1046,7 +1046,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(out, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, out)
+    beginNamedMixinApplication(class, null, null, out)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1064,7 +1064,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'part' as a name here., null, {lexeme: part}], part, part)
     handleIdentifier(part, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, part)
+    beginNamedMixinApplication(class, null, null, part)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1081,7 +1081,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(patch, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, patch)
+    beginNamedMixinApplication(class, null, null, patch)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1099,7 +1099,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'required' as a name here., null, {lexeme: required}], required, required)
     handleIdentifier(required, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, required)
+    beginNamedMixinApplication(class, null, null, required)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1117,7 +1117,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'rethrow' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: rethrow}], rethrow, rethrow)
     handleIdentifier(rethrow, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, rethrow)
+    beginNamedMixinApplication(class, null, null, rethrow)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1135,7 +1135,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'return' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: return}], return, return)
     handleIdentifier(return, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, return)
+    beginNamedMixinApplication(class, null, null, return)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1153,7 +1153,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'set' as a name here., null, {lexeme: set}], set, set)
     handleIdentifier(set, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, set)
+    beginNamedMixinApplication(class, null, null, set)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1170,7 +1170,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(show, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, show)
+    beginNamedMixinApplication(class, null, null, show)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1187,7 +1187,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(source, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, source)
+    beginNamedMixinApplication(class, null, null, source)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1205,7 +1205,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'static' as a name here., null, {lexeme: static}], static, static)
     handleIdentifier(static, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, static)
+    beginNamedMixinApplication(class, null, null, static)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1223,7 +1223,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'super' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: super}], super, super)
     handleIdentifier(super, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, super)
+    beginNamedMixinApplication(class, null, null, super)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1241,7 +1241,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'switch' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: switch}], switch, switch)
     handleIdentifier(switch, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, switch)
+    beginNamedMixinApplication(class, null, null, switch)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1258,7 +1258,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(sync, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, sync)
+    beginNamedMixinApplication(class, null, null, sync)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1276,7 +1276,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'this' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: this}], this, this)
     handleIdentifier(this, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, this)
+    beginNamedMixinApplication(class, null, null, this)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1294,7 +1294,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'throw' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: throw}], throw, throw)
     handleIdentifier(throw, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, throw)
+    beginNamedMixinApplication(class, null, null, throw)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1312,7 +1312,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'true' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: true}], true, true)
     handleIdentifier(true, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, true)
+    beginNamedMixinApplication(class, null, null, true)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1330,7 +1330,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'try' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: try}], try, try)
     handleIdentifier(try, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, try)
+    beginNamedMixinApplication(class, null, null, try)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1348,7 +1348,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'typedef' as a name here., null, {lexeme: typedef}], typedef, typedef)
     handleIdentifier(typedef, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, typedef)
+    beginNamedMixinApplication(class, null, null, typedef)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1366,7 +1366,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'var' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: var}], var, var)
     handleIdentifier(var, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, var)
+    beginNamedMixinApplication(class, null, null, var)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1384,7 +1384,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'void' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: void}], void, void)
     handleIdentifier(void, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, void)
+    beginNamedMixinApplication(class, null, null, void)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1402,7 +1402,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'while' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: while}], while, while)
     handleIdentifier(while, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, while)
+    beginNamedMixinApplication(class, null, null, while)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1420,7 +1420,7 @@
     handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'with' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: with}], with, with)
     handleIdentifier(with, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, with)
+    beginNamedMixinApplication(class, null, null, with)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
@@ -1437,7 +1437,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(yield, classOrMixinDeclaration)
     handleNoTypeVariables(=)
-    beginNamedMixinApplication(class, null, yield)
+    beginNamedMixinApplication(class, null, null, yield)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments(with)
       handleType(A, null)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_1.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_1.dart.intertwined.expect
index 5e0bb61..732268f 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_1.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_1.dart.intertwined.expect
@@ -6,16 +6,16 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(abstract, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'abstract' as a name here., null, {lexeme: abstract}], abstract, abstract)
           listener: handleIdentifier(abstract, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, abstract)
+        listener: beginNamedMixinApplication(class, null, null, abstract)
         parseNamedMixinApplication(abstract, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -35,16 +35,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(as, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'as' as a name here., null, {lexeme: as}], as, as)
           listener: handleIdentifier(as, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, as)
+        listener: beginNamedMixinApplication(class, null, null, as)
         parseNamedMixinApplication(as, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -64,16 +64,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(assert, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'assert' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: assert}], assert, assert)
           listener: handleIdentifier(assert, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, assert)
+        listener: beginNamedMixinApplication(class, null, null, assert)
         parseNamedMixinApplication(assert, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -93,14 +93,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(async, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, async)
+        listener: beginNamedMixinApplication(class, null, null, async)
         parseNamedMixinApplication(async, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -120,14 +120,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(await, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, await)
+        listener: beginNamedMixinApplication(class, null, null, await)
         parseNamedMixinApplication(await, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -147,16 +147,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(break, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'break' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: break}], break, break)
           listener: handleIdentifier(break, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, break)
+        listener: beginNamedMixinApplication(class, null, null, break)
         parseNamedMixinApplication(break, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -176,16 +176,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(case, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'case' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: case}], case, case)
           listener: handleIdentifier(case, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, case)
+        listener: beginNamedMixinApplication(class, null, null, case)
         parseNamedMixinApplication(case, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -205,16 +205,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(catch, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'catch' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: catch}], catch, catch)
           listener: handleIdentifier(catch, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, catch)
+        listener: beginNamedMixinApplication(class, null, null, catch)
         parseNamedMixinApplication(catch, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -234,16 +234,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(class, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'class' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: class}], class, class)
           listener: handleIdentifier(class, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, class)
+        listener: beginNamedMixinApplication(class, null, null, class)
         parseNamedMixinApplication(class, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -263,16 +263,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(const, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'const' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: const}], const, const)
           listener: handleIdentifier(const, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, const)
+        listener: beginNamedMixinApplication(class, null, null, const)
         parseNamedMixinApplication(const, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -292,16 +292,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(continue, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'continue' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: continue}], continue, continue)
           listener: handleIdentifier(continue, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, continue)
+        listener: beginNamedMixinApplication(class, null, null, continue)
         parseNamedMixinApplication(continue, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -321,16 +321,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(covariant, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'covariant' as a name here., null, {lexeme: covariant}], covariant, covariant)
           listener: handleIdentifier(covariant, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, covariant)
+        listener: beginNamedMixinApplication(class, null, null, covariant)
         parseNamedMixinApplication(covariant, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -350,16 +350,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(default, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'default' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: default}], default, default)
           listener: handleIdentifier(default, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, default)
+        listener: beginNamedMixinApplication(class, null, null, default)
         parseNamedMixinApplication(default, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -379,16 +379,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(deferred, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'deferred' as a name here., null, {lexeme: deferred}], deferred, deferred)
           listener: handleIdentifier(deferred, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, deferred)
+        listener: beginNamedMixinApplication(class, null, null, deferred)
         parseNamedMixinApplication(deferred, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -408,16 +408,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(do, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'do' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: do}], do, do)
           listener: handleIdentifier(do, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, do)
+        listener: beginNamedMixinApplication(class, null, null, do)
         parseNamedMixinApplication(do, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -437,16 +437,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(dynamic, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'dynamic' as a name here., null, {lexeme: dynamic}], dynamic, dynamic)
           listener: handleIdentifier(dynamic, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, dynamic)
+        listener: beginNamedMixinApplication(class, null, null, dynamic)
         parseNamedMixinApplication(dynamic, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -466,16 +466,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(else, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'else' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: else}], else, else)
           listener: handleIdentifier(else, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, else)
+        listener: beginNamedMixinApplication(class, null, null, else)
         parseNamedMixinApplication(else, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -495,16 +495,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(enum, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'enum' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: enum}], enum, enum)
           listener: handleIdentifier(enum, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, enum)
+        listener: beginNamedMixinApplication(class, null, null, enum)
         parseNamedMixinApplication(enum, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -524,16 +524,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(export, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'export' as a name here., null, {lexeme: export}], export, export)
           listener: handleIdentifier(export, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, export)
+        listener: beginNamedMixinApplication(class, null, null, export)
         parseNamedMixinApplication(export, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -553,16 +553,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(extends, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'extends' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: extends}], extends, extends)
           listener: handleIdentifier(extends, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, extends)
+        listener: beginNamedMixinApplication(class, null, null, extends)
         parseNamedMixinApplication(extends, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -582,16 +582,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(extension, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'extension' as a name here., null, {lexeme: extension}], extension, extension)
           listener: handleIdentifier(extension, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, extension)
+        listener: beginNamedMixinApplication(class, null, null, extension)
         parseNamedMixinApplication(extension, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -611,16 +611,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(external, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'external' as a name here., null, {lexeme: external}], external, external)
           listener: handleIdentifier(external, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, external)
+        listener: beginNamedMixinApplication(class, null, null, external)
         parseNamedMixinApplication(external, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -640,16 +640,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(factory, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'factory' as a name here., null, {lexeme: factory}], factory, factory)
           listener: handleIdentifier(factory, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, factory)
+        listener: beginNamedMixinApplication(class, null, null, factory)
         parseNamedMixinApplication(factory, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -669,16 +669,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(false, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'false' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: false}], false, false)
           listener: handleIdentifier(false, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, false)
+        listener: beginNamedMixinApplication(class, null, null, false)
         parseNamedMixinApplication(false, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -698,16 +698,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(final, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'final' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: final}], final, final)
           listener: handleIdentifier(final, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, final)
+        listener: beginNamedMixinApplication(class, null, null, final)
         parseNamedMixinApplication(final, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -727,16 +727,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(finally, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'finally' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: finally}], finally, finally)
           listener: handleIdentifier(finally, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, finally)
+        listener: beginNamedMixinApplication(class, null, null, finally)
         parseNamedMixinApplication(finally, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -756,16 +756,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(for, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'for' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: for}], for, for)
           listener: handleIdentifier(for, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, for)
+        listener: beginNamedMixinApplication(class, null, null, for)
         parseNamedMixinApplication(for, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -785,14 +785,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Function, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, Function)
+        listener: beginNamedMixinApplication(class, null, null, Function)
         parseNamedMixinApplication(Function, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -812,16 +812,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(get, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'get' as a name here., null, {lexeme: get}], get, get)
           listener: handleIdentifier(get, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, get)
+        listener: beginNamedMixinApplication(class, null, null, get)
         parseNamedMixinApplication(get, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -841,14 +841,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(hide, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, hide)
+        listener: beginNamedMixinApplication(class, null, null, hide)
         parseNamedMixinApplication(hide, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -868,16 +868,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(if, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'if' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: if}], if, if)
           listener: handleIdentifier(if, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, if)
+        listener: beginNamedMixinApplication(class, null, null, if)
         parseNamedMixinApplication(if, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -897,16 +897,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(implements, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'implements' as a name here., null, {lexeme: implements}], implements, implements)
           listener: handleIdentifier(implements, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, implements)
+        listener: beginNamedMixinApplication(class, null, null, implements)
         parseNamedMixinApplication(implements, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -926,16 +926,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(import, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'import' as a name here., null, {lexeme: import}], import, import)
           listener: handleIdentifier(import, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, import)
+        listener: beginNamedMixinApplication(class, null, null, import)
         parseNamedMixinApplication(import, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -955,16 +955,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(in, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'in' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: in}], in, in)
           listener: handleIdentifier(in, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, in)
+        listener: beginNamedMixinApplication(class, null, null, in)
         parseNamedMixinApplication(in, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -984,14 +984,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(inout, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, inout)
+        listener: beginNamedMixinApplication(class, null, null, inout)
         parseNamedMixinApplication(inout, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1011,16 +1011,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(interface, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'interface' as a name here., null, {lexeme: interface}], interface, interface)
           listener: handleIdentifier(interface, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, interface)
+        listener: beginNamedMixinApplication(class, null, null, interface)
         parseNamedMixinApplication(interface, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1040,16 +1040,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(is, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'is' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: is}], is, is)
           listener: handleIdentifier(is, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, is)
+        listener: beginNamedMixinApplication(class, null, null, is)
         parseNamedMixinApplication(is, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1069,16 +1069,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(late, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'late' as a name here., null, {lexeme: late}], late, late)
           listener: handleIdentifier(late, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, late)
+        listener: beginNamedMixinApplication(class, null, null, late)
         parseNamedMixinApplication(late, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1098,16 +1098,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(library, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'library' as a name here., null, {lexeme: library}], library, library)
           listener: handleIdentifier(library, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, library)
+        listener: beginNamedMixinApplication(class, null, null, library)
         parseNamedMixinApplication(library, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1127,16 +1127,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(mixin, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'mixin' as a name here., null, {lexeme: mixin}], mixin, mixin)
           listener: handleIdentifier(mixin, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, mixin)
+        listener: beginNamedMixinApplication(class, null, null, mixin)
         parseNamedMixinApplication(mixin, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1156,14 +1156,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(native, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, native)
+        listener: beginNamedMixinApplication(class, null, null, native)
         parseNamedMixinApplication(native, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1183,16 +1183,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(new, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'new' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: new}], new, new)
           listener: handleIdentifier(new, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, new)
+        listener: beginNamedMixinApplication(class, null, null, new)
         parseNamedMixinApplication(new, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1212,16 +1212,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(null, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'null' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: null}], null, null)
           listener: handleIdentifier(null, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, null)
+        listener: beginNamedMixinApplication(class, null, null, null)
         parseNamedMixinApplication(null, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1241,14 +1241,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(of, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, of)
+        listener: beginNamedMixinApplication(class, null, null, of)
         parseNamedMixinApplication(of, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1268,14 +1268,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(on, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, on)
+        listener: beginNamedMixinApplication(class, null, null, on)
         parseNamedMixinApplication(on, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1295,16 +1295,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(operator, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'operator' as a name here., null, {lexeme: operator}], operator, operator)
           listener: handleIdentifier(operator, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, operator)
+        listener: beginNamedMixinApplication(class, null, null, operator)
         parseNamedMixinApplication(operator, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1324,14 +1324,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(out, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, out)
+        listener: beginNamedMixinApplication(class, null, null, out)
         parseNamedMixinApplication(out, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1351,16 +1351,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(part, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'part' as a name here., null, {lexeme: part}], part, part)
           listener: handleIdentifier(part, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, part)
+        listener: beginNamedMixinApplication(class, null, null, part)
         parseNamedMixinApplication(part, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1380,14 +1380,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(patch, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, patch)
+        listener: beginNamedMixinApplication(class, null, null, patch)
         parseNamedMixinApplication(patch, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1407,16 +1407,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(required, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'required' as a name here., null, {lexeme: required}], required, required)
           listener: handleIdentifier(required, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, required)
+        listener: beginNamedMixinApplication(class, null, null, required)
         parseNamedMixinApplication(required, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1436,16 +1436,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(rethrow, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'rethrow' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: rethrow}], rethrow, rethrow)
           listener: handleIdentifier(rethrow, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, rethrow)
+        listener: beginNamedMixinApplication(class, null, null, rethrow)
         parseNamedMixinApplication(rethrow, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1465,16 +1465,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(return, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'return' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: return}], return, return)
           listener: handleIdentifier(return, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, return)
+        listener: beginNamedMixinApplication(class, null, null, return)
         parseNamedMixinApplication(return, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1494,16 +1494,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(set, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'set' as a name here., null, {lexeme: set}], set, set)
           listener: handleIdentifier(set, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, set)
+        listener: beginNamedMixinApplication(class, null, null, set)
         parseNamedMixinApplication(set, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1523,14 +1523,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(show, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, show)
+        listener: beginNamedMixinApplication(class, null, null, show)
         parseNamedMixinApplication(show, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1550,14 +1550,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(source, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, source)
+        listener: beginNamedMixinApplication(class, null, null, source)
         parseNamedMixinApplication(source, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1577,16 +1577,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(static, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'static' as a name here., null, {lexeme: static}], static, static)
           listener: handleIdentifier(static, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, static)
+        listener: beginNamedMixinApplication(class, null, null, static)
         parseNamedMixinApplication(static, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1606,16 +1606,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(super, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'super' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: super}], super, super)
           listener: handleIdentifier(super, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, super)
+        listener: beginNamedMixinApplication(class, null, null, super)
         parseNamedMixinApplication(super, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1635,16 +1635,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(switch, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'switch' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: switch}], switch, switch)
           listener: handleIdentifier(switch, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, switch)
+        listener: beginNamedMixinApplication(class, null, null, switch)
         parseNamedMixinApplication(switch, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1664,14 +1664,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(sync, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, sync)
+        listener: beginNamedMixinApplication(class, null, null, sync)
         parseNamedMixinApplication(sync, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1691,16 +1691,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(this, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'this' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: this}], this, this)
           listener: handleIdentifier(this, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, this)
+        listener: beginNamedMixinApplication(class, null, null, this)
         parseNamedMixinApplication(this, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1720,16 +1720,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(throw, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'throw' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: throw}], throw, throw)
           listener: handleIdentifier(throw, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, throw)
+        listener: beginNamedMixinApplication(class, null, null, throw)
         parseNamedMixinApplication(throw, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1749,16 +1749,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(true, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'true' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: true}], true, true)
           listener: handleIdentifier(true, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, true)
+        listener: beginNamedMixinApplication(class, null, null, true)
         parseNamedMixinApplication(true, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1778,16 +1778,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(try, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'try' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: try}], try, try)
           listener: handleIdentifier(try, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, try)
+        listener: beginNamedMixinApplication(class, null, null, try)
         parseNamedMixinApplication(try, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1807,16 +1807,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(typedef, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'typedef' as a name here., null, {lexeme: typedef}], typedef, typedef)
           listener: handleIdentifier(typedef, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, typedef)
+        listener: beginNamedMixinApplication(class, null, null, typedef)
         parseNamedMixinApplication(typedef, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1836,16 +1836,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(var, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'var' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: var}], var, var)
           listener: handleIdentifier(var, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, var)
+        listener: beginNamedMixinApplication(class, null, null, var)
         parseNamedMixinApplication(var, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1865,16 +1865,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(void, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'void' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: void}], void, void)
           listener: handleIdentifier(void, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, void)
+        listener: beginNamedMixinApplication(class, null, null, void)
         parseNamedMixinApplication(void, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1894,16 +1894,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(while, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'while' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: while}], while, while)
           listener: handleIdentifier(while, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, while)
+        listener: beginNamedMixinApplication(class, null, null, while)
         parseNamedMixinApplication(while, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1923,16 +1923,16 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(with, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[ExpectedIdentifierButGotKeyword, 'with' can't be used as an identifier because it's a keyword., Try renaming this to be an identifier that isn't a keyword., {lexeme: with}], with, with)
           listener: handleIdentifier(with, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, with)
+        listener: beginNamedMixinApplication(class, null, null, with)
         parseNamedMixinApplication(with, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
@@ -1952,14 +1952,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(yield, classOrMixinDeclaration)
         listener: handleNoTypeVariables(=)
-        listener: beginNamedMixinApplication(class, null, yield)
+        listener: beginNamedMixinApplication(class, null, null, yield)
         parseNamedMixinApplication(yield, class, class)
           listener: handleIdentifier(A, typeReference)
           listener: handleNoTypeArguments(with)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_2.dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_2.dart.expect
index c531ce9..4d447d1 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_2.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_2.dart.expect
@@ -20,7 +20,7 @@
     // WARNING: Reporting at eof for .
     handleIdentifier(, classOrMixinDeclaration)
     handleNoTypeVariables()
-    beginClassDeclaration(class, null, )
+    beginClassDeclaration(class, null, null, )
       handleNoType()
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_2.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_2.dart.intertwined.expect
index 7f36933..64a2d2b 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_2.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46346_prime_2.dart.intertwined.expect
@@ -6,9 +6,9 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           insertSyntheticIdentifier(class, classOrMixinDeclaration, message: Message[ExpectedIdentifier, Expected an identifier, but got ''., Try inserting an identifier before ''., {lexeme: }], messageOnToken: null)
@@ -18,7 +18,7 @@
             rewriter()
           listener: handleIdentifier(, classOrMixinDeclaration)
         listener: handleNoTypeVariables()
-        listener: beginClassDeclaration(class, null, )
+        listener: beginClassDeclaration(class, null, null, )
         parseClass(, class, class, )
           parseClassHeaderOpt(, class, class)
             parseClassExtendsOpt()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46505.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46505.crash_dart.expect
index 5319e1e..63e8b06 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46505.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46505.crash_dart.expect
@@ -30,7 +30,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -67,7 +67,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(B, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, B)
+    beginClassDeclaration(class, null, null, B)
       handleNoType(B)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46505.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46505.crash_dart.intertwined.expect
index 2084366..08cfe6a 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46505.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46505.crash_dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
@@ -73,14 +73,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(B, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, B)
+        listener: beginClassDeclaration(class, null, null, B)
         parseClass(B, class, class, B)
           parseClassHeaderOpt(B, class, class)
             parseClassExtendsOpt(B)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_1.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_1.crash_dart.expect
index 57ee430..a9ee40d 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_1.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_1.crash_dart.expect
@@ -10,7 +10,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_1.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_1.crash_dart.intertwined.expect
index 7943b6e..4ee602f 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_1.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_1.crash_dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_2.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_2.crash_dart.expect
index 9966ba4..78cd4a8 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_2.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_2.crash_dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_2.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_2.crash_dart.intertwined.expect
index ef59ba8..f5178bd 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_2.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_2.crash_dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_3.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_3.crash_dart.expect
index e72edce..dad6879 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_3.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_3.crash_dart.expect
@@ -18,7 +18,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_3.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_3.crash_dart.intertwined.expect
index facee11..058793d 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_3.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_3.crash_dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_4.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_4.crash_dart.expect
index c08729f..fc06fb1 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_4.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_4.crash_dart.expect
@@ -18,7 +18,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_4.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_4.crash_dart.intertwined.expect
index 6b797ae..0f37588 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_4.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_4.crash_dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_5.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_5.crash_dart.expect
index 2f106f1..e10973c 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_5.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_5.crash_dart.expect
@@ -82,7 +82,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -127,7 +127,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(B, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, B)
+    beginClassDeclaration(class, null, null, B)
       handleNoType(B)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -199,7 +199,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_5.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_5.crash_dart.intertwined.expect
index 67c819d..fc2c4c6 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_5.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_5.crash_dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
@@ -83,14 +83,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(B, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, B)
+        listener: beginClassDeclaration(class, null, null, B)
         parseClass(B, class, class, B)
           parseClassHeaderOpt(B, class, class)
             parseClassExtendsOpt(B)
@@ -197,14 +197,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_6.crash_dart.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_6.crash_dart.expect
index 1c4ffc0..151c812 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_6.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_6.crash_dart.expect
@@ -10,7 +10,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_6.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_6.crash_dart.intertwined.expect
index b5de8a7..4c286fe 100644
--- a/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_6.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/issue_46505_prime_6.crash_dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
diff --git a/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_fields.dart.expect b/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_fields.dart.expect
index 40b87ef..673d794 100644
--- a/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_fields.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_fields.dart.expect
@@ -138,7 +138,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(WrapperClass, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, WrapperClass)
+    beginClassDeclaration(class, null, null, WrapperClass)
       handleNoType(WrapperClass)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_fields.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_fields.dart.intertwined.expect
index 769412a..c6060ad 100644
--- a/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_fields.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_fields.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(WrapperClass, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, WrapperClass)
+        listener: beginClassDeclaration(class, null, null, WrapperClass)
         parseClass(WrapperClass, class, class, WrapperClass)
           parseClassHeaderOpt(WrapperClass, class, class)
             parseClassExtendsOpt(WrapperClass)
diff --git a/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_methods.dart.expect b/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_methods.dart.expect
index bf58a68..a281a5c 100644
--- a/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_methods.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_methods.dart.expect
@@ -478,7 +478,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(WrapperClass, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, WrapperClass)
+    beginClassDeclaration(class, null, null, WrapperClass)
       handleNoType(WrapperClass)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_methods.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_methods.dart.intertwined.expect
index 22c9cba..75b6cd7 100644
--- a/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_methods.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/keyword_named_class_methods.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(WrapperClass, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, WrapperClass)
+        listener: beginClassDeclaration(class, null, null, WrapperClass)
         parseClass(WrapperClass, class, class, WrapperClass)
           parseClassHeaderOpt(WrapperClass, class, class)
             parseClassExtendsOpt(WrapperClass)
diff --git a/pkg/front_end/parser_testcases/error_recovery/keyword_named_formal_parameter_start_of_next_top_level.dart.expect b/pkg/front_end/parser_testcases/error_recovery/keyword_named_formal_parameter_start_of_next_top_level.dart.expect
index 6085b02..5b96bf3 100644
--- a/pkg/front_end/parser_testcases/error_recovery/keyword_named_formal_parameter_start_of_next_top_level.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/keyword_named_formal_parameter_start_of_next_top_level.dart.expect
@@ -35,7 +35,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/keyword_named_formal_parameter_start_of_next_top_level.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/keyword_named_formal_parameter_start_of_next_top_level.dart.intertwined.expect
index 194b6ca..0b284d4 100644
--- a/pkg/front_end/parser_testcases/error_recovery/keyword_named_formal_parameter_start_of_next_top_level.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/keyword_named_formal_parameter_start_of_next_top_level.dart.intertwined.expect
@@ -49,14 +49,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
diff --git a/pkg/front_end/parser_testcases/error_recovery/keyword_named_typedefs.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/keyword_named_typedefs.dart.intertwined.expect
index 77d7a90..93da896 100644
--- a/pkg/front_end/parser_testcases/error_recovery/keyword_named_typedefs.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/keyword_named_typedefs.dart.intertwined.expect
@@ -6,7 +6,7 @@
     parseMetadataStar()
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -28,7 +28,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -53,7 +53,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -75,7 +75,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -100,7 +100,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -122,7 +122,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -147,7 +147,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -167,7 +167,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -190,7 +190,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -210,7 +210,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -233,7 +233,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -255,7 +255,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -280,7 +280,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -302,7 +302,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -327,7 +327,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -349,7 +349,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -374,7 +374,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -396,7 +396,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -421,7 +421,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -443,7 +443,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -468,7 +468,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -490,7 +490,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -515,7 +515,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -537,7 +537,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -562,7 +562,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -584,7 +584,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -609,7 +609,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -631,7 +631,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -656,7 +656,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -678,7 +678,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -703,7 +703,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -725,7 +725,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -750,7 +750,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -772,7 +772,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -797,7 +797,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -819,7 +819,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -844,7 +844,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -866,7 +866,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -891,7 +891,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -913,7 +913,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -938,7 +938,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -960,7 +960,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -985,7 +985,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1007,7 +1007,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1032,7 +1032,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1054,7 +1054,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1079,7 +1079,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1101,7 +1101,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1126,7 +1126,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1148,7 +1148,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1173,7 +1173,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1195,7 +1195,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1220,7 +1220,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1242,7 +1242,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1267,7 +1267,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1289,7 +1289,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1314,7 +1314,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1336,7 +1336,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1361,7 +1361,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1381,7 +1381,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1404,7 +1404,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1426,7 +1426,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1451,7 +1451,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1473,7 +1473,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1498,7 +1498,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1520,7 +1520,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1545,7 +1545,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1567,7 +1567,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1592,7 +1592,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1612,7 +1612,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1635,7 +1635,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1657,7 +1657,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1682,7 +1682,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1704,7 +1704,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1729,7 +1729,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1751,7 +1751,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1776,7 +1776,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1798,7 +1798,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1823,7 +1823,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1845,7 +1845,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1870,7 +1870,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1890,7 +1890,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1913,7 +1913,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1935,7 +1935,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1960,7 +1960,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1982,7 +1982,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2007,7 +2007,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2027,7 +2027,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2050,7 +2050,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2070,7 +2070,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2093,7 +2093,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2115,7 +2115,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2140,7 +2140,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2160,7 +2160,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2183,7 +2183,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2205,7 +2205,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2230,7 +2230,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2250,7 +2250,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2273,7 +2273,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2295,7 +2295,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2320,7 +2320,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2342,7 +2342,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2367,7 +2367,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2389,7 +2389,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2414,7 +2414,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2436,7 +2436,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2461,7 +2461,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2481,7 +2481,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2504,7 +2504,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2524,7 +2524,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2547,7 +2547,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2569,7 +2569,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2594,7 +2594,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2616,7 +2616,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2641,7 +2641,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2663,7 +2663,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2688,7 +2688,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2708,7 +2708,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2731,7 +2731,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2753,7 +2753,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2778,7 +2778,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2800,7 +2800,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2825,7 +2825,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2847,7 +2847,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2872,7 +2872,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2894,7 +2894,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2919,7 +2919,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2941,7 +2941,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2966,7 +2966,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -2988,7 +2988,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -3013,7 +3013,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -3035,7 +3035,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -3103,7 +3103,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -3125,7 +3125,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -3150,7 +3150,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -3172,7 +3172,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -3197,7 +3197,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -3217,7 +3217,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
diff --git a/pkg/front_end/parser_testcases/error_recovery/method_called_with.dart.expect b/pkg/front_end/parser_testcases/error_recovery/method_called_with.dart.expect
index 3ec322e..38ec0b6 100644
--- a/pkg/front_end/parser_testcases/error_recovery/method_called_with.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/method_called_with.dart.expect
@@ -30,7 +30,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/method_called_with.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/method_called_with.dart.intertwined.expect
index a3ee2de..eaf2a2d 100644
--- a/pkg/front_end/parser_testcases/error_recovery/method_called_with.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/method_called_with.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
diff --git a/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime.dart.expect b/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime.dart.expect
index 5f2c8b0..ce905c8 100644
--- a/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime.dart.intertwined.expect
index 0bfc02a..74b3c11 100644
--- a/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
diff --git a/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime2.dart.expect b/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime2.dart.expect
index 2975c4f..fe1e36e 100644
--- a/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime2.dart.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime2.dart.expect
@@ -26,7 +26,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(B, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, B)
+    beginClassDeclaration(class, null, null, B)
       handleNoType(B)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -52,7 +52,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(M1, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, M1)
+    beginClassDeclaration(class, null, null, M1)
       handleNoType(M1)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime2.dart.intertwined.expect b/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime2.dart.intertwined.expect
index ec3e1aa..86fc4d7 100644
--- a/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime2.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/error_recovery/method_called_with_prime2.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(B, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, B)
+        listener: beginClassDeclaration(class, null, null, B)
         parseClass(B, class, class, B)
           parseClassHeaderOpt(B, class, class)
             parseClassExtendsOpt(B)
@@ -57,14 +57,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(M1, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, M1)
+        listener: beginClassDeclaration(class, null, null, M1)
         parseClass(M1, class, class, M1)
           parseClassHeaderOpt(M1, class, class)
             parseClassExtendsOpt(M1)
diff --git a/pkg/front_end/parser_testcases/extension_named_type.dart.expect b/pkg/front_end/parser_testcases/extension_named_type.dart.expect
index cf2bd6f..3f37bf0 100644
--- a/pkg/front_end/parser_testcases/extension_named_type.dart.expect
+++ b/pkg/front_end/parser_testcases/extension_named_type.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/extension_named_type.dart.intertwined.expect b/pkg/front_end/parser_testcases/extension_named_type.dart.intertwined.expect
index f67f847..39d1b6c 100644
--- a/pkg/front_end/parser_testcases/extension_named_type.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/extension_named_type.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
@@ -34,7 +34,7 @@
     parseMetadataStar(})
       listener: beginMetadataStar(extension)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, extension, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, extension, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(}, extension)
       parseExtension(extension)
         listener: beginExtensionDeclarationPrelude(extension)
diff --git a/pkg/front_end/parser_testcases/extension_type.dart.expect b/pkg/front_end/parser_testcases/extension_type.dart.expect
index 69cafad..2eb3be8 100644
--- a/pkg/front_end/parser_testcases/extension_type.dart.expect
+++ b/pkg/front_end/parser_testcases/extension_type.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/extension_type.dart.intertwined.expect b/pkg/front_end/parser_testcases/extension_type.dart.intertwined.expect
index 200f4ca..e59e494 100644
--- a/pkg/front_end/parser_testcases/extension_type.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/extension_type.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
@@ -34,7 +34,7 @@
     parseMetadataStar(})
       listener: beginMetadataStar(extension)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, extension, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, extension, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(}, extension)
       parseExtension(extension)
         listener: beginExtensionDeclarationPrelude(extension)
diff --git a/pkg/front_end/parser_testcases/extensions/covariant.dart.expect b/pkg/front_end/parser_testcases/extensions/covariant.dart.expect
index 2d5e28f..01e24a9 100644
--- a/pkg/front_end/parser_testcases/extensions/covariant.dart.expect
+++ b/pkg/front_end/parser_testcases/extensions/covariant.dart.expect
@@ -10,7 +10,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -25,7 +25,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables(extends)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments({)
       handleType(A, null)
diff --git a/pkg/front_end/parser_testcases/extensions/covariant.dart.intertwined.expect b/pkg/front_end/parser_testcases/extensions/covariant.dart.intertwined.expect
index 8dac2d3..1394b80 100644
--- a/pkg/front_end/parser_testcases/extensions/covariant.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/extensions/covariant.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
@@ -34,14 +34,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables(extends)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
@@ -65,7 +65,7 @@
     parseMetadataStar(})
       listener: beginMetadataStar(extension)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, extension, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, extension, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(}, extension)
       parseExtension(extension)
         listener: beginExtensionDeclarationPrelude(extension)
diff --git a/pkg/front_end/parser_testcases/extensions/not_covariant.dart.expect b/pkg/front_end/parser_testcases/extensions/not_covariant.dart.expect
index a66993b..9f907a0 100644
--- a/pkg/front_end/parser_testcases/extensions/not_covariant.dart.expect
+++ b/pkg/front_end/parser_testcases/extensions/not_covariant.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -19,7 +19,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables(extends)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments({)
       handleType(A, null)
diff --git a/pkg/front_end/parser_testcases/extensions/not_covariant.dart.intertwined.expect b/pkg/front_end/parser_testcases/extensions/not_covariant.dart.intertwined.expect
index 8b610fd..fa98447 100644
--- a/pkg/front_end/parser_testcases/extensions/not_covariant.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/extensions/not_covariant.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
@@ -34,14 +34,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables(extends)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
@@ -65,7 +65,7 @@
     parseMetadataStar(})
       listener: beginMetadataStar(extension)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, extension, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, extension, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(}, extension)
       parseExtension(extension)
         listener: beginExtensionDeclarationPrelude(extension)
diff --git a/pkg/front_end/parser_testcases/extensions/static.dart.expect b/pkg/front_end/parser_testcases/extensions/static.dart.expect
index 0a73b25..cb69c93 100644
--- a/pkg/front_end/parser_testcases/extensions/static.dart.expect
+++ b/pkg/front_end/parser_testcases/extensions/static.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -19,7 +19,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables(extends)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments({)
       handleType(A, null)
diff --git a/pkg/front_end/parser_testcases/extensions/static.dart.intertwined.expect b/pkg/front_end/parser_testcases/extensions/static.dart.intertwined.expect
index 9efff07..ac55bc5 100644
--- a/pkg/front_end/parser_testcases/extensions/static.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/extensions/static.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
@@ -34,14 +34,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables(extends)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
@@ -65,7 +65,7 @@
     parseMetadataStar(})
       listener: beginMetadataStar(extension)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, extension, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, extension, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(}, extension)
       parseExtension(extension)
         listener: beginExtensionDeclarationPrelude(extension)
diff --git a/pkg/front_end/parser_testcases/extensions/static_covariant.dart.expect b/pkg/front_end/parser_testcases/extensions/static_covariant.dart.expect
index 6e3a17c..8efa048 100644
--- a/pkg/front_end/parser_testcases/extensions/static_covariant.dart.expect
+++ b/pkg/front_end/parser_testcases/extensions/static_covariant.dart.expect
@@ -10,7 +10,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -25,7 +25,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables(extends)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleIdentifier(A, typeReference)
       handleNoTypeArguments({)
       handleType(A, null)
diff --git a/pkg/front_end/parser_testcases/extensions/static_covariant.dart.intertwined.expect b/pkg/front_end/parser_testcases/extensions/static_covariant.dart.intertwined.expect
index c7ba3ab..ef95892 100644
--- a/pkg/front_end/parser_testcases/extensions/static_covariant.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/extensions/static_covariant.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
@@ -34,14 +34,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables(extends)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
@@ -65,7 +65,7 @@
     parseMetadataStar(})
       listener: beginMetadataStar(extension)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, extension, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, extension, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(}, extension)
       parseExtension(extension)
         listener: beginExtensionDeclarationPrelude(extension)
diff --git a/pkg/front_end/parser_testcases/general/built_in_identifier_class_fields.dart.expect b/pkg/front_end/parser_testcases/general/built_in_identifier_class_fields.dart.expect
index ea7558e..c8d6b3b 100644
--- a/pkg/front_end/parser_testcases/general/built_in_identifier_class_fields.dart.expect
+++ b/pkg/front_end/parser_testcases/general/built_in_identifier_class_fields.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(WrapperClass, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, WrapperClass)
+    beginClassDeclaration(class, null, null, WrapperClass)
       handleNoType(WrapperClass)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/general/built_in_identifier_class_fields.dart.intertwined.expect b/pkg/front_end/parser_testcases/general/built_in_identifier_class_fields.dart.intertwined.expect
index 4196505..1ec01c0 100644
--- a/pkg/front_end/parser_testcases/general/built_in_identifier_class_fields.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/general/built_in_identifier_class_fields.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(WrapperClass, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, WrapperClass)
+        listener: beginClassDeclaration(class, null, null, WrapperClass)
         parseClass(WrapperClass, class, class, WrapperClass)
           parseClassHeaderOpt(WrapperClass, class, class)
             parseClassExtendsOpt(WrapperClass)
diff --git a/pkg/front_end/parser_testcases/general/built_in_identifier_class_methods.dart.expect b/pkg/front_end/parser_testcases/general/built_in_identifier_class_methods.dart.expect
index be1cef5..b89c4ab 100644
--- a/pkg/front_end/parser_testcases/general/built_in_identifier_class_methods.dart.expect
+++ b/pkg/front_end/parser_testcases/general/built_in_identifier_class_methods.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(WrapperClass, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, WrapperClass)
+    beginClassDeclaration(class, null, null, WrapperClass)
       handleNoType(WrapperClass)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/general/built_in_identifier_class_methods.dart.intertwined.expect b/pkg/front_end/parser_testcases/general/built_in_identifier_class_methods.dart.intertwined.expect
index 7196e63..375106c 100644
--- a/pkg/front_end/parser_testcases/general/built_in_identifier_class_methods.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/general/built_in_identifier_class_methods.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(WrapperClass, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, WrapperClass)
+        listener: beginClassDeclaration(class, null, null, WrapperClass)
         parseClass(WrapperClass, class, class, WrapperClass)
           parseClassHeaderOpt(WrapperClass, class, class)
             parseClassExtendsOpt(WrapperClass)
diff --git a/pkg/front_end/parser_testcases/general/generic_function_typedef.dart.intertwined.expect b/pkg/front_end/parser_testcases/general/generic_function_typedef.dart.intertwined.expect
index ef579de..1615902 100644
--- a/pkg/front_end/parser_testcases/general/generic_function_typedef.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/general/generic_function_typedef.dart.intertwined.expect
@@ -6,7 +6,7 @@
     parseMetadataStar()
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -37,7 +37,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -72,7 +72,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -113,7 +113,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -158,7 +158,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -203,7 +203,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -248,7 +248,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -279,7 +279,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -314,7 +314,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -355,7 +355,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -400,7 +400,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -445,7 +445,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -490,7 +490,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -533,7 +533,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -580,7 +580,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -643,7 +643,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -710,7 +710,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -767,7 +767,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -824,7 +824,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -871,7 +871,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -922,7 +922,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -979,7 +979,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1040,7 +1040,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1101,7 +1101,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
diff --git a/pkg/front_end/parser_testcases/general/issue_41121.dart.expect b/pkg/front_end/parser_testcases/general/issue_41121.dart.expect
index 31e37e0..9132fd3 100644
--- a/pkg/front_end/parser_testcases/general/issue_41121.dart.expect
+++ b/pkg/front_end/parser_testcases/general/issue_41121.dart.expect
@@ -46,7 +46,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(ConfigurationService, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, ConfigurationService)
+    beginClassDeclaration(class, null, null, ConfigurationService)
       handleNoType(ConfigurationService)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -275,7 +275,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Configuration, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Configuration)
+    beginClassDeclaration(class, null, null, Configuration)
       handleNoType(Configuration)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/general/issue_41121.dart.intertwined.expect b/pkg/front_end/parser_testcases/general/issue_41121.dart.intertwined.expect
index ee486f9..d392486 100644
--- a/pkg/front_end/parser_testcases/general/issue_41121.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/general/issue_41121.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(ConfigurationService, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, ConfigurationService)
+        listener: beginClassDeclaration(class, null, null, ConfigurationService)
         parseClass(ConfigurationService, class, class, ConfigurationService)
           parseClassHeaderOpt(ConfigurationService, class, class)
             parseClassExtendsOpt(ConfigurationService)
@@ -511,14 +511,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Configuration, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Configuration)
+        listener: beginClassDeclaration(class, null, null, Configuration)
         parseClass(Configuration, class, class, Configuration)
           parseClassHeaderOpt(Configuration, class, class)
             parseClassExtendsOpt(Configuration)
diff --git a/pkg/front_end/parser_testcases/general/issue_45120.dart.intertwined.expect b/pkg/front_end/parser_testcases/general/issue_45120.dart.intertwined.expect
index 1d825dd..94b8325 100644
--- a/pkg/front_end/parser_testcases/general/issue_45120.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/general/issue_45120.dart.intertwined.expect
@@ -28,7 +28,7 @@
               listener: endArguments(1, (, ))
         listener: endMetadata(@, null, typedef)
       listener: endMetadataStar(1)
-    parseTopLevelKeywordDeclaration(), typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(), typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(), typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
diff --git a/pkg/front_end/parser_testcases/general/metadata.dart.expect b/pkg/front_end/parser_testcases/general/metadata.dart.expect
index 591d9e1..b86186a 100644
--- a/pkg/front_end/parser_testcases/general/metadata.dart.expect
+++ b/pkg/front_end/parser_testcases/general/metadata.dart.expect
@@ -107,7 +107,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(X, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, X)
+    beginClassDeclaration(class, null, null, X)
       handleNoType(X)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -939,7 +939,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Y, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Y)
+    beginClassDeclaration(class, null, null, Y)
       handleNoType(Y)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/general/metadata.dart.intertwined.expect b/pkg/front_end/parser_testcases/general/metadata.dart.intertwined.expect
index 676c00f..3432673 100644
--- a/pkg/front_end/parser_testcases/general/metadata.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/general/metadata.dart.intertwined.expect
@@ -228,14 +228,14 @@
               listener: endArguments(1, (, ))
         listener: endMetadata(@, ., class)
       listener: endMetadataStar(10)
-    parseTopLevelKeywordDeclaration(), class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(), class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(), class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(X, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, X)
+        listener: beginClassDeclaration(class, null, null, X)
         parseClass(X, class, class, X)
           parseClassHeaderOpt(X, class, class)
             parseClassExtendsOpt(X)
@@ -256,7 +256,7 @@
     parseMetadataStar(})
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(}, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -343,7 +343,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -442,7 +442,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -547,7 +547,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -664,7 +664,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -796,7 +796,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -934,7 +934,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1063,7 +1063,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1201,7 +1201,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1342,7 +1342,7 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(typedef)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, typedef, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, typedef, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(;, typedef)
       parseTypedef(typedef)
         listener: beginUncategorizedTopLevelDeclaration(typedef)
@@ -1713,14 +1713,14 @@
               listener: endArguments(1, (, ))
         listener: endMetadata(@, ., class)
       listener: endMetadataStar(9)
-    parseTopLevelKeywordDeclaration(), class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(), class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(), class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Y, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Y)
+        listener: beginClassDeclaration(class, null, null, Y)
         parseClass(Y, class, class, Y)
           parseClassHeaderOpt(Y, class, class)
             parseClassExtendsOpt(Y)
diff --git a/pkg/front_end/parser_testcases/general/new_as_identifier.dart.expect b/pkg/front_end/parser_testcases/general/new_as_identifier.dart.expect
index 988d84a..419693a 100644
--- a/pkg/front_end/parser_testcases/general/new_as_identifier.dart.expect
+++ b/pkg/front_end/parser_testcases/general/new_as_identifier.dart.expect
@@ -46,7 +46,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -147,7 +147,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(D, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, D)
+    beginClassDeclaration(class, null, null, D)
       handleNoType(D)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/general/new_as_identifier.dart.intertwined.expect b/pkg/front_end/parser_testcases/general/new_as_identifier.dart.intertwined.expect
index a0d0817..5976ef9 100644
--- a/pkg/front_end/parser_testcases/general/new_as_identifier.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/general/new_as_identifier.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
@@ -233,14 +233,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(D, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, D)
+        listener: beginClassDeclaration(class, null, null, D)
         parseClass(D, class, class, D)
           parseClassHeaderOpt(D, class, class)
             parseClassExtendsOpt(D)
diff --git a/pkg/front_end/parser_testcases/general/operator_01.dart.expect b/pkg/front_end/parser_testcases/general/operator_01.dart.expect
index 7a98e55..5c996b6 100644
--- a/pkg/front_end/parser_testcases/general/operator_01.dart.expect
+++ b/pkg/front_end/parser_testcases/general/operator_01.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/general/operator_01.dart.intertwined.expect b/pkg/front_end/parser_testcases/general/operator_01.dart.intertwined.expect
index 150a67f..21ad05a 100644
--- a/pkg/front_end/parser_testcases/general/operator_01.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/general/operator_01.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/general/operator_hat_class.crash_dart.expect b/pkg/front_end/parser_testcases/general/operator_hat_class.crash_dart.expect
index 220fb22..52352ee 100644
--- a/pkg/front_end/parser_testcases/general/operator_hat_class.crash_dart.expect
+++ b/pkg/front_end/parser_testcases/general/operator_hat_class.crash_dart.expect
@@ -11,7 +11,7 @@
     handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'operator' as a name here., null, {lexeme: operator}], operator, operator)
     handleIdentifier(operator, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, operator)
+    beginClassDeclaration(class, null, null, operator)
       handleNoType(operator)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/general/operator_hat_class.crash_dart.intertwined.expect b/pkg/front_end/parser_testcases/general/operator_hat_class.crash_dart.intertwined.expect
index ae300e1..710f8db 100644
--- a/pkg/front_end/parser_testcases/general/operator_hat_class.crash_dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/general/operator_hat_class.crash_dart.intertwined.expect
@@ -6,16 +6,16 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           reportRecoverableErrorWithToken(operator, Instance of 'Template<(Token) => Message>')
             listener: handleRecoverableError(Message[BuiltInIdentifierInDeclaration, Can't use 'operator' as a name here., null, {lexeme: operator}], operator, operator)
           listener: handleIdentifier(operator, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, operator)
+        listener: beginClassDeclaration(class, null, null, operator)
         parseClass(operator, class, class, operator)
           parseClassHeaderOpt(operator, class, class)
             parseClassExtendsOpt(operator)
diff --git a/pkg/front_end/parser_testcases/macros/macro_class.dart b/pkg/front_end/parser_testcases/macros/macro_class.dart
new file mode 100644
index 0000000..02bfe1f
--- /dev/null
+++ b/pkg/front_end/parser_testcases/macros/macro_class.dart
@@ -0,0 +1,4 @@
+macro class Class {}
+abstract macro class Class {}
+macro class Class = Object with Mixin;
+abstract macro class Class = Object with Mixin;
\ No newline at end of file
diff --git a/pkg/front_end/parser_testcases/macros/macro_class.dart.expect b/pkg/front_end/parser_testcases/macros/macro_class.dart.expect
new file mode 100644
index 0000000..3198253
--- /dev/null
+++ b/pkg/front_end/parser_testcases/macros/macro_class.dart.expect
@@ -0,0 +1,66 @@
+beginCompilationUnit(macro)
+  beginMetadataStar(macro)
+  endMetadataStar(0)
+  beginClassOrMixinOrNamedMixinApplicationPrelude(class)
+    handleIdentifier(Class, classOrMixinDeclaration)
+    handleNoTypeVariables({)
+    beginClassDeclaration(class, null, macro, Class)
+      handleNoType(Class)
+      handleClassExtends(null, 1)
+      handleClassNoWithClause()
+      handleImplements(null, 0)
+      handleClassHeader(class, class, null)
+      beginClassOrMixinOrExtensionBody(DeclarationKind.Class, {)
+      endClassOrMixinOrExtensionBody(DeclarationKind.Class, 0, {, })
+    endClassDeclaration(class, })
+  endTopLevelDeclaration(abstract)
+  beginMetadataStar(abstract)
+  endMetadataStar(0)
+  beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
+    handleIdentifier(Class, classOrMixinDeclaration)
+    handleNoTypeVariables({)
+    beginClassDeclaration(abstract, abstract, macro, Class)
+      handleNoType(Class)
+      handleClassExtends(null, 1)
+      handleClassNoWithClause()
+      handleImplements(null, 0)
+      handleClassHeader(abstract, class, null)
+      beginClassOrMixinOrExtensionBody(DeclarationKind.Class, {)
+      endClassOrMixinOrExtensionBody(DeclarationKind.Class, 0, {, })
+    endClassDeclaration(abstract, })
+  endTopLevelDeclaration(macro)
+  beginMetadataStar(macro)
+  endMetadataStar(0)
+  beginClassOrMixinOrNamedMixinApplicationPrelude(class)
+    handleIdentifier(Class, classOrMixinDeclaration)
+    handleNoTypeVariables(=)
+    beginNamedMixinApplication(class, null, macro, Class)
+      handleIdentifier(Object, typeReference)
+      handleNoTypeArguments(with)
+      handleType(Object, null)
+      beginTypeList(Mixin)
+        handleIdentifier(Mixin, typeReference)
+        handleNoTypeArguments(;)
+        handleType(Mixin, null)
+      endTypeList(1)
+      handleNamedMixinApplicationWithClause(with)
+    endNamedMixinApplication(class, class, =, null, ;)
+  endTopLevelDeclaration(abstract)
+  beginMetadataStar(abstract)
+  endMetadataStar(0)
+  beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
+    handleIdentifier(Class, classOrMixinDeclaration)
+    handleNoTypeVariables(=)
+    beginNamedMixinApplication(abstract, abstract, macro, Class)
+      handleIdentifier(Object, typeReference)
+      handleNoTypeArguments(with)
+      handleType(Object, null)
+      beginTypeList(Mixin)
+        handleIdentifier(Mixin, typeReference)
+        handleNoTypeArguments(;)
+        handleType(Mixin, null)
+      endTypeList(1)
+      handleNamedMixinApplicationWithClause(with)
+    endNamedMixinApplication(abstract, class, =, null, ;)
+  endTopLevelDeclaration()
+endCompilationUnit(4, )
diff --git a/pkg/front_end/parser_testcases/macros/macro_class.dart.intertwined.expect b/pkg/front_end/parser_testcases/macros/macro_class.dart.intertwined.expect
new file mode 100644
index 0000000..08e38d8
--- /dev/null
+++ b/pkg/front_end/parser_testcases/macros/macro_class.dart.intertwined.expect
@@ -0,0 +1,118 @@
+parseUnit(macro)
+  skipErrorTokens(macro)
+  listener: beginCompilationUnit(macro)
+  syntheticPreviousToken(macro)
+  parseTopLevelDeclarationImpl(, Instance of 'DirectiveContext')
+    parseMetadataStar()
+      listener: beginMetadataStar(macro)
+      listener: endMetadataStar(0)
+    parseTopLevelKeywordDeclaration(, class, macro, Instance of 'DirectiveContext')
+      parseClassDeclarationModifiers(, macro)
+      parseClassOrNamedMixinApplication(null, macro, class)
+        listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
+        ensureIdentifier(class, classOrMixinDeclaration)
+          listener: handleIdentifier(Class, classOrMixinDeclaration)
+        listener: handleNoTypeVariables({)
+        listener: beginClassDeclaration(class, null, macro, Class)
+        parseClass(Class, class, class, Class)
+          parseClassHeaderOpt(Class, class, class)
+            parseClassExtendsOpt(Class)
+              listener: handleNoType(Class)
+              listener: handleClassExtends(null, 1)
+            parseClassWithClauseOpt(Class)
+              listener: handleClassNoWithClause()
+            parseClassOrMixinOrEnumImplementsOpt(Class)
+              listener: handleImplements(null, 0)
+            listener: handleClassHeader(class, class, null)
+          parseClassOrMixinOrExtensionBody(Class, DeclarationKind.Class, Class)
+            listener: beginClassOrMixinOrExtensionBody(DeclarationKind.Class, {)
+            notEofOrValue(}, })
+            listener: endClassOrMixinOrExtensionBody(DeclarationKind.Class, 0, {, })
+          listener: endClassDeclaration(class, })
+  listener: endTopLevelDeclaration(abstract)
+  parseTopLevelDeclarationImpl(}, Instance of 'DirectiveContext')
+    parseMetadataStar(})
+      listener: beginMetadataStar(abstract)
+      listener: endMetadataStar(0)
+    parseTopLevelKeywordDeclaration(}, class, macro, Instance of 'DirectiveContext')
+      parseClassDeclarationModifiers(}, macro)
+        parseTopLevelKeywordModifiers(abstract, macro)
+      parseClassOrNamedMixinApplication(abstract, macro, class)
+        listener: beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
+        ensureIdentifier(class, classOrMixinDeclaration)
+          listener: handleIdentifier(Class, classOrMixinDeclaration)
+        listener: handleNoTypeVariables({)
+        listener: beginClassDeclaration(abstract, abstract, macro, Class)
+        parseClass(Class, abstract, class, Class)
+          parseClassHeaderOpt(Class, abstract, class)
+            parseClassExtendsOpt(Class)
+              listener: handleNoType(Class)
+              listener: handleClassExtends(null, 1)
+            parseClassWithClauseOpt(Class)
+              listener: handleClassNoWithClause()
+            parseClassOrMixinOrEnumImplementsOpt(Class)
+              listener: handleImplements(null, 0)
+            listener: handleClassHeader(abstract, class, null)
+          parseClassOrMixinOrExtensionBody(Class, DeclarationKind.Class, Class)
+            listener: beginClassOrMixinOrExtensionBody(DeclarationKind.Class, {)
+            notEofOrValue(}, })
+            listener: endClassOrMixinOrExtensionBody(DeclarationKind.Class, 0, {, })
+          listener: endClassDeclaration(abstract, })
+  listener: endTopLevelDeclaration(macro)
+  parseTopLevelDeclarationImpl(}, Instance of 'DirectiveContext')
+    parseMetadataStar(})
+      listener: beginMetadataStar(macro)
+      listener: endMetadataStar(0)
+    parseTopLevelKeywordDeclaration(}, class, macro, Instance of 'DirectiveContext')
+      parseClassDeclarationModifiers(}, macro)
+      parseClassOrNamedMixinApplication(null, macro, class)
+        listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
+        ensureIdentifier(class, classOrMixinDeclaration)
+          listener: handleIdentifier(Class, classOrMixinDeclaration)
+        listener: handleNoTypeVariables(=)
+        listener: beginNamedMixinApplication(class, null, macro, Class)
+        parseNamedMixinApplication(Class, class, class)
+          listener: handleIdentifier(Object, typeReference)
+          listener: handleNoTypeArguments(with)
+          listener: handleType(Object, null)
+          parseMixinApplicationRest(Object)
+            parseTypeList(with)
+              listener: beginTypeList(Mixin)
+              listener: handleIdentifier(Mixin, typeReference)
+              listener: handleNoTypeArguments(;)
+              listener: handleType(Mixin, null)
+              listener: endTypeList(1)
+            listener: handleNamedMixinApplicationWithClause(with)
+          ensureSemicolon(Mixin)
+          listener: endNamedMixinApplication(class, class, =, null, ;)
+  listener: endTopLevelDeclaration(abstract)
+  parseTopLevelDeclarationImpl(;, Instance of 'DirectiveContext')
+    parseMetadataStar(;)
+      listener: beginMetadataStar(abstract)
+      listener: endMetadataStar(0)
+    parseTopLevelKeywordDeclaration(;, class, macro, Instance of 'DirectiveContext')
+      parseClassDeclarationModifiers(;, macro)
+        parseTopLevelKeywordModifiers(abstract, macro)
+      parseClassOrNamedMixinApplication(abstract, macro, class)
+        listener: beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
+        ensureIdentifier(class, classOrMixinDeclaration)
+          listener: handleIdentifier(Class, classOrMixinDeclaration)
+        listener: handleNoTypeVariables(=)
+        listener: beginNamedMixinApplication(abstract, abstract, macro, Class)
+        parseNamedMixinApplication(Class, abstract, class)
+          listener: handleIdentifier(Object, typeReference)
+          listener: handleNoTypeArguments(with)
+          listener: handleType(Object, null)
+          parseMixinApplicationRest(Object)
+            parseTypeList(with)
+              listener: beginTypeList(Mixin)
+              listener: handleIdentifier(Mixin, typeReference)
+              listener: handleNoTypeArguments(;)
+              listener: handleType(Mixin, null)
+              listener: endTypeList(1)
+            listener: handleNamedMixinApplicationWithClause(with)
+          ensureSemicolon(Mixin)
+          listener: endNamedMixinApplication(abstract, class, =, null, ;)
+  listener: endTopLevelDeclaration()
+  reportAllErrorTokens(macro)
+  listener: endCompilationUnit(4, )
diff --git a/pkg/front_end/parser_testcases/macros/macro_class.dart.parser.expect b/pkg/front_end/parser_testcases/macros/macro_class.dart.parser.expect
new file mode 100644
index 0000000..cdcf2eb
--- /dev/null
+++ b/pkg/front_end/parser_testcases/macros/macro_class.dart.parser.expect
@@ -0,0 +1,9 @@
+macro class Class {}
+abstract macro class Class {}
+macro class Class = Object with Mixin;
+abstract macro class Class = Object with Mixin;
+
+macro[StringToken] class[KeywordToken] Class[StringToken] {[BeginToken]}[SimpleToken]
+abstract[KeywordToken] macro[StringToken] class[KeywordToken] Class[StringToken] {[BeginToken]}[SimpleToken]
+macro[StringToken] class[KeywordToken] Class[StringToken] =[SimpleToken] Object[StringToken] with[KeywordToken] Mixin[StringToken];[SimpleToken]
+abstract[KeywordToken] macro[StringToken] class[KeywordToken] Class[StringToken] =[SimpleToken] Object[StringToken] with[KeywordToken] Mixin[StringToken];[SimpleToken][SimpleToken]
diff --git a/pkg/front_end/parser_testcases/macros/macro_class.dart.scanner.expect b/pkg/front_end/parser_testcases/macros/macro_class.dart.scanner.expect
new file mode 100644
index 0000000..cdcf2eb
--- /dev/null
+++ b/pkg/front_end/parser_testcases/macros/macro_class.dart.scanner.expect
@@ -0,0 +1,9 @@
+macro class Class {}
+abstract macro class Class {}
+macro class Class = Object with Mixin;
+abstract macro class Class = Object with Mixin;
+
+macro[StringToken] class[KeywordToken] Class[StringToken] {[BeginToken]}[SimpleToken]
+abstract[KeywordToken] macro[StringToken] class[KeywordToken] Class[StringToken] {[BeginToken]}[SimpleToken]
+macro[StringToken] class[KeywordToken] Class[StringToken] =[SimpleToken] Object[StringToken] with[KeywordToken] Mixin[StringToken];[SimpleToken]
+abstract[KeywordToken] macro[StringToken] class[KeywordToken] Class[StringToken] =[SimpleToken] Object[StringToken] with[KeywordToken] Mixin[StringToken];[SimpleToken][SimpleToken]
diff --git a/pkg/front_end/parser_testcases/nnbd/error_recovery/abstract_placement.dart.expect b/pkg/front_end/parser_testcases/nnbd/error_recovery/abstract_placement.dart.expect
index 431b3ea..048ba71 100644
--- a/pkg/front_end/parser_testcases/nnbd/error_recovery/abstract_placement.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/error_recovery/abstract_placement.dart.expect
@@ -58,7 +58,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(abstract, abstract, C)
+    beginClassDeclaration(abstract, abstract, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -170,7 +170,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
     handleIdentifier(Bar, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(abstract, abstract, Bar)
+    beginClassDeclaration(abstract, abstract, null, Bar)
       handleNoType(Bar)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/error_recovery/abstract_placement.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/error_recovery/abstract_placement.dart.intertwined.expect
index 0dad422..525c27c 100644
--- a/pkg/front_end/parser_testcases/nnbd/error_recovery/abstract_placement.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/error_recovery/abstract_placement.dart.intertwined.expect
@@ -6,15 +6,15 @@
     parseMetadataStar()
       listener: beginMetadataStar(abstract)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
         parseTopLevelKeywordModifiers(abstract, class)
-      parseClassOrNamedMixinApplication(abstract, class)
+      parseClassOrNamedMixinApplication(abstract, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(abstract, abstract, C)
+        listener: beginClassDeclaration(abstract, abstract, null, C)
         parseClass(C, abstract, class, C)
           parseClassHeaderOpt(C, abstract, class)
             parseClassExtendsOpt(C)
@@ -199,15 +199,15 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(abstract)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
         parseTopLevelKeywordModifiers(abstract, class)
-      parseClassOrNamedMixinApplication(abstract, class)
+      parseClassOrNamedMixinApplication(abstract, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Bar, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(abstract, abstract, Bar)
+        listener: beginClassDeclaration(abstract, abstract, null, Bar)
         parseClass(Bar, abstract, class, Bar)
           parseClassHeaderOpt(Bar, abstract, class)
             parseClassExtendsOpt(Bar)
diff --git a/pkg/front_end/parser_testcases/nnbd/error_recovery/external_placement.dart.expect b/pkg/front_end/parser_testcases/nnbd/error_recovery/external_placement.dart.expect
index 0f039f2..1542fd5 100644
--- a/pkg/front_end/parser_testcases/nnbd/error_recovery/external_placement.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/error_recovery/external_placement.dart.expect
@@ -64,7 +64,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/error_recovery/external_placement.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/error_recovery/external_placement.dart.intertwined.expect
index b6e296e..23beab2 100644
--- a/pkg/front_end/parser_testcases/nnbd/error_recovery/external_placement.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/error_recovery/external_placement.dart.intertwined.expect
@@ -42,14 +42,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
diff --git a/pkg/front_end/parser_testcases/nnbd/error_recovery/late_without_var_etc.dart.expect b/pkg/front_end/parser_testcases/nnbd/error_recovery/late_without_var_etc.dart.expect
index ff7df27..d9f84e6 100644
--- a/pkg/front_end/parser_testcases/nnbd/error_recovery/late_without_var_etc.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/error_recovery/late_without_var_etc.dart.expect
@@ -60,7 +60,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/error_recovery/late_without_var_etc.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/error_recovery/late_without_var_etc.dart.intertwined.expect
index b3d9581..c5b6907 100644
--- a/pkg/front_end/parser_testcases/nnbd/error_recovery/late_without_var_etc.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/error_recovery/late_without_var_etc.dart.intertwined.expect
@@ -73,14 +73,14 @@
     parseMetadataStar(;)
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(;, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(;, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(;, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_39723.dart.expect b/pkg/front_end/parser_testcases/nnbd/issue_39723.dart.expect
index e8f8cc3..9d5ae52 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_39723.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_39723.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_39723.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/issue_39723.dart.intertwined.expect
index 48f91db..4271b3d 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_39723.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_39723.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_39723_prime.dart.expect b/pkg/front_end/parser_testcases/nnbd/issue_39723_prime.dart.expect
index 0917000..c583b3c 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_39723_prime.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_39723_prime.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(A, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(A)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_39723_prime.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/issue_39723_prime.dart.intertwined.expect
index fb8706d..4124e8f 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_39723_prime.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_39723_prime.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(A, class, class, A)
           parseClassHeaderOpt(A, class, class)
             parseClassExtendsOpt(A)
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_39858.dart.expect b/pkg/front_end/parser_testcases/nnbd/issue_39858.dart.expect
index 3928968..174b591 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_39858.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_39858.dart.expect
@@ -30,7 +30,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(X, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, X)
+    beginClassDeclaration(class, null, null, X)
       handleNoType(X)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_39858.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/issue_39858.dart.intertwined.expect
index dbb38a1..281f0c0 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_39858.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_39858.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(X, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, X)
+        listener: beginClassDeclaration(class, null, null, X)
         parseClass(X, class, class, X)
           parseClassHeaderOpt(X, class, class)
             parseClassExtendsOpt(X)
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_39858_prime1.dart.expect b/pkg/front_end/parser_testcases/nnbd/issue_39858_prime1.dart.expect
index 000e5f1..33dcf4a 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_39858_prime1.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_39858_prime1.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(X, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, X)
+    beginClassDeclaration(class, null, null, X)
       handleNoType(X)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_39858_prime1.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/issue_39858_prime1.dart.intertwined.expect
index 390d560..167db06 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_39858_prime1.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_39858_prime1.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(X, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, X)
+        listener: beginClassDeclaration(class, null, null, X)
         parseClass(X, class, class, X)
           parseClassHeaderOpt(X, class, class)
             parseClassExtendsOpt(X)
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_40805_01.dart.expect b/pkg/front_end/parser_testcases/nnbd/issue_40805_01.dart.expect
index c8d1dbb..507ba0a 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_40805_01.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_40805_01.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_40805_01.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/issue_40805_01.dart.intertwined.expect
index d9d2694..2c7dd9e 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_40805_01.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_40805_01.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_40805_02.dart.expect b/pkg/front_end/parser_testcases/nnbd/issue_40805_02.dart.expect
index 5ee07df..dc9c09c 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_40805_02.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_40805_02.dart.expect
@@ -10,7 +10,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_40805_02.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/issue_40805_02.dart.intertwined.expect
index 6458925..b8addec 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_40805_02.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_40805_02.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_40805_03.dart.expect b/pkg/front_end/parser_testcases/nnbd/issue_40805_03.dart.expect
index a29e8f2..b3f7815 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_40805_03.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_40805_03.dart.expect
@@ -10,7 +10,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_40805_03.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/issue_40805_03.dart.intertwined.expect
index da73524..884d7c4 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_40805_03.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_40805_03.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_40834_01.dart.expect b/pkg/front_end/parser_testcases/nnbd/issue_40834_01.dart.expect
index 1d39a3c..483e3af 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_40834_01.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_40834_01.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_40834_01.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/issue_40834_01.dart.intertwined.expect
index 6a80fc4..1b44701 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_40834_01.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_40834_01.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_40834_02.dart.expect b/pkg/front_end/parser_testcases/nnbd/issue_40834_02.dart.expect
index a8f4c2d..a5a1d9f 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_40834_02.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_40834_02.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_40834_02.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/issue_40834_02.dart.intertwined.expect
index b03cb1b..a2fe16d 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_40834_02.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_40834_02.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_40834_03.dart.expect b/pkg/front_end/parser_testcases/nnbd/issue_40834_03.dart.expect
index d9b3888..151beb8 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_40834_03.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_40834_03.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_40834_03.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/issue_40834_03.dart.intertwined.expect
index 7ac308d..ea077fe 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_40834_03.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_40834_03.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_41597.dart.expect b/pkg/front_end/parser_testcases/nnbd/issue_41597.dart.expect
index 627e902..3a0663e 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_41597.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_41597.dart.expect
@@ -72,7 +72,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_41597.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/issue_41597.dart.intertwined.expect
index fd8e6dc..6ade11d 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_41597.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_41597.dart.intertwined.expect
@@ -186,14 +186,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_42621.dart.expect b/pkg/front_end/parser_testcases/nnbd/issue_42621.dart.expect
index a4fad4a..c107cbf 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_42621.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_42621.dart.expect
@@ -308,7 +308,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Order, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Order)
+    beginClassDeclaration(class, null, null, Order)
       handleNoType(Order)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/issue_42621.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/issue_42621.dart.intertwined.expect
index 319ea20..263bcd9 100644
--- a/pkg/front_end/parser_testcases/nnbd/issue_42621.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/issue_42621.dart.intertwined.expect
@@ -634,14 +634,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Order, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Order)
+        listener: beginClassDeclaration(class, null, null, Order)
         parseClass(Order, class, class, Order)
           parseClassHeaderOpt(Order, class, class)
             parseClassExtendsOpt(Order)
diff --git a/pkg/front_end/parser_testcases/nnbd/late_member.dart.expect b/pkg/front_end/parser_testcases/nnbd/late_member.dart.expect
index 00eb347..ec45784 100644
--- a/pkg/front_end/parser_testcases/nnbd/late_member.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/late_member.dart.expect
@@ -123,7 +123,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(X, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, X)
+    beginClassDeclaration(class, null, null, X)
       handleNoType(X)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -161,7 +161,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Y, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Y)
+    beginClassDeclaration(class, null, null, Y)
       handleNoType(Y)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/late_member.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/late_member.dart.intertwined.expect
index 362c55c..8fb9358 100644
--- a/pkg/front_end/parser_testcases/nnbd/late_member.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/late_member.dart.intertwined.expect
@@ -325,14 +325,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(X, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, X)
+        listener: beginClassDeclaration(class, null, null, X)
         parseClass(X, class, class, X)
           parseClassHeaderOpt(X, class, class)
             parseClassExtendsOpt(X)
@@ -417,14 +417,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Y, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Y)
+        listener: beginClassDeclaration(class, null, null, Y)
         parseClass(Y, class, class, Y)
           parseClassHeaderOpt(Y, class, class)
             parseClassExtendsOpt(Y)
diff --git a/pkg/front_end/parser_testcases/nnbd/late_modifier.dart.expect b/pkg/front_end/parser_testcases/nnbd/late_modifier.dart.expect
index e528774..7d1c8bd 100644
--- a/pkg/front_end/parser_testcases/nnbd/late_modifier.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/late_modifier.dart.expect
@@ -141,7 +141,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(X, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, X)
+    beginClassDeclaration(class, null, null, X)
       handleNoType(X)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -179,7 +179,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Y, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Y)
+    beginClassDeclaration(class, null, null, Y)
       handleNoType(Y)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/late_modifier.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/late_modifier.dart.intertwined.expect
index a61b867..7c01aa3 100644
--- a/pkg/front_end/parser_testcases/nnbd/late_modifier.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/late_modifier.dart.intertwined.expect
@@ -374,14 +374,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(X, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, X)
+        listener: beginClassDeclaration(class, null, null, X)
         parseClass(X, class, class, X)
           parseClassHeaderOpt(X, class, class)
             parseClassExtendsOpt(X)
@@ -466,14 +466,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Y, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Y)
+        listener: beginClassDeclaration(class, null, null, Y)
         parseClass(Y, class, class, Y)
           parseClassHeaderOpt(Y, class, class)
             parseClassExtendsOpt(Y)
diff --git a/pkg/front_end/parser_testcases/nnbd/null_shorting_index.dart.expect b/pkg/front_end/parser_testcases/nnbd/null_shorting_index.dart.expect
index 45f4ec7..92ef663 100644
--- a/pkg/front_end/parser_testcases/nnbd/null_shorting_index.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/null_shorting_index.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Class1, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Class1)
+    beginClassDeclaration(class, null, null, Class1)
       handleNoType(Class1)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/null_shorting_index.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/null_shorting_index.dart.intertwined.expect
index fa8e973..d9b1e75 100644
--- a/pkg/front_end/parser_testcases/nnbd/null_shorting_index.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/null_shorting_index.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Class1, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Class1)
+        listener: beginClassDeclaration(class, null, null, Class1)
         parseClass(Class1, class, class, Class1)
           parseClassHeaderOpt(Class1, class, class)
             parseClassExtendsOpt(Class1)
diff --git a/pkg/front_end/parser_testcases/nnbd/required_member.dart.expect b/pkg/front_end/parser_testcases/nnbd/required_member.dart.expect
index b2d3c4d..8f3bab8 100644
--- a/pkg/front_end/parser_testcases/nnbd/required_member.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/required_member.dart.expect
@@ -123,7 +123,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(X, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, X)
+    beginClassDeclaration(class, null, null, X)
       handleNoType(X)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -161,7 +161,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Y, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Y)
+    beginClassDeclaration(class, null, null, Y)
       handleNoType(Y)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/required_member.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/required_member.dart.intertwined.expect
index 84da6c5..8506b7e 100644
--- a/pkg/front_end/parser_testcases/nnbd/required_member.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/required_member.dart.intertwined.expect
@@ -325,14 +325,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(X, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, X)
+        listener: beginClassDeclaration(class, null, null, X)
         parseClass(X, class, class, X)
           parseClassHeaderOpt(X, class, class)
             parseClassExtendsOpt(X)
@@ -417,14 +417,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Y, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Y)
+        listener: beginClassDeclaration(class, null, null, Y)
         parseClass(Y, class, class, Y)
           parseClassHeaderOpt(Y, class, class)
             parseClassExtendsOpt(Y)
diff --git a/pkg/front_end/parser_testcases/nnbd/required_modifier.dart.expect b/pkg/front_end/parser_testcases/nnbd/required_modifier.dart.expect
index 8af1629..9bd3e32 100644
--- a/pkg/front_end/parser_testcases/nnbd/required_modifier.dart.expect
+++ b/pkg/front_end/parser_testcases/nnbd/required_modifier.dart.expect
@@ -134,7 +134,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(X, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, X)
+    beginClassDeclaration(class, null, null, X)
       handleNoType(X)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -172,7 +172,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Y, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Y)
+    beginClassDeclaration(class, null, null, Y)
       handleNoType(Y)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/nnbd/required_modifier.dart.intertwined.expect b/pkg/front_end/parser_testcases/nnbd/required_modifier.dart.intertwined.expect
index a184fd5..7523c1c 100644
--- a/pkg/front_end/parser_testcases/nnbd/required_modifier.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/nnbd/required_modifier.dart.intertwined.expect
@@ -341,14 +341,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(X, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, X)
+        listener: beginClassDeclaration(class, null, null, X)
         parseClass(X, class, class, X)
           parseClassHeaderOpt(X, class, class)
             parseClassExtendsOpt(X)
@@ -433,14 +433,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Y, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Y)
+        listener: beginClassDeclaration(class, null, null, Y)
         parseClass(Y, class, class, Y)
           parseClassHeaderOpt(Y, class, class)
             parseClassExtendsOpt(Y)
diff --git a/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method.dart.expect b/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method.dart.expect
index e5eb201..ded8c58 100644
--- a/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method.dart.expect
+++ b/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method.dart.expect
@@ -26,7 +26,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method.dart.intertwined.expect b/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method.dart.intertwined.expect
index 823d3fc..e396b6a 100644
--- a/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method_prime.dart.expect b/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method_prime.dart.expect
index df508f2..5f001f3 100644
--- a/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method_prime.dart.expect
+++ b/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method_prime.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method_prime.dart.intertwined.expect b/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method_prime.dart.intertwined.expect
index 30851c1..6f0f152 100644
--- a/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method_prime.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/no-triple-shift/define_triple_shift_method_prime.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/no-triple-shift/triple_shift_not_triple_shift.dart.expect b/pkg/front_end/parser_testcases/no-triple-shift/triple_shift_not_triple_shift.dart.expect
index c29258b..80b04fe 100644
--- a/pkg/front_end/parser_testcases/no-triple-shift/triple_shift_not_triple_shift.dart.expect
+++ b/pkg/front_end/parser_testcases/no-triple-shift/triple_shift_not_triple_shift.dart.expect
@@ -94,7 +94,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables(extends)
-    beginClassDeclaration(abstract, abstract, Foo)
+    beginClassDeclaration(abstract, abstract, null, Foo)
       handleIdentifier(List, typeReference)
       beginTypeArguments(<)
         handleIdentifier(List, typeReference)
diff --git a/pkg/front_end/parser_testcases/no-triple-shift/triple_shift_not_triple_shift.dart.intertwined.expect b/pkg/front_end/parser_testcases/no-triple-shift/triple_shift_not_triple_shift.dart.intertwined.expect
index 1917d68..3a379e4 100644
--- a/pkg/front_end/parser_testcases/no-triple-shift/triple_shift_not_triple_shift.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/no-triple-shift/triple_shift_not_triple_shift.dart.intertwined.expect
@@ -6,7 +6,7 @@
     parseMetadataStar()
       listener: beginMetadataStar(extension)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, extension, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, extension, null, Instance of 'DirectiveContext')
       parseTopLevelKeywordModifiers(, extension)
       parseExtension(extension)
         listener: beginExtensionDeclarationPrelude(extension)
@@ -206,15 +206,15 @@
     parseMetadataStar(})
       listener: beginMetadataStar(abstract)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
         parseTopLevelKeywordModifiers(abstract, class)
-      parseClassOrNamedMixinApplication(abstract, class)
+      parseClassOrNamedMixinApplication(abstract, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(abstract)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables(extends)
-        listener: beginClassDeclaration(abstract, abstract, Foo)
+        listener: beginClassDeclaration(abstract, abstract, null, Foo)
         parseClass(Foo, abstract, class, Foo)
           parseClassHeaderOpt(Foo, abstract, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/non-nnbd/issue_40288.dart.expect b/pkg/front_end/parser_testcases/non-nnbd/issue_40288.dart.expect
index bf983c2..667962a 100644
--- a/pkg/front_end/parser_testcases/non-nnbd/issue_40288.dart.expect
+++ b/pkg/front_end/parser_testcases/non-nnbd/issue_40288.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(late, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, late)
+    beginClassDeclaration(class, null, null, late)
       handleNoType(late)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -35,7 +35,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(required, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, required)
+    beginClassDeclaration(class, null, null, required)
       handleNoType(required)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -66,7 +66,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/non-nnbd/issue_40288.dart.intertwined.expect b/pkg/front_end/parser_testcases/non-nnbd/issue_40288.dart.intertwined.expect
index 2a31e5e..c89a6b0 100644
--- a/pkg/front_end/parser_testcases/non-nnbd/issue_40288.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/non-nnbd/issue_40288.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(late, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, late)
+        listener: beginClassDeclaration(class, null, null, late)
         parseClass(late, class, class, late)
           parseClassHeaderOpt(late, class, class)
             parseClassExtendsOpt(late)
@@ -71,14 +71,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(required, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, required)
+        listener: beginClassDeclaration(class, null, null, required)
         parseClass(required, class, class, required)
           parseClassHeaderOpt(required, class, class)
             parseClassExtendsOpt(required)
@@ -136,14 +136,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
diff --git a/pkg/front_end/parser_testcases/non-nnbd/issue_40288_prime.dart.expect b/pkg/front_end/parser_testcases/non-nnbd/issue_40288_prime.dart.expect
index 73ec228..d54d704 100644
--- a/pkg/front_end/parser_testcases/non-nnbd/issue_40288_prime.dart.expect
+++ b/pkg/front_end/parser_testcases/non-nnbd/issue_40288_prime.dart.expect
@@ -4,7 +4,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Xlate, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Xlate)
+    beginClassDeclaration(class, null, null, Xlate)
       handleNoType(Xlate)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -35,7 +35,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Xrequired, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Xrequired)
+    beginClassDeclaration(class, null, null, Xrequired)
       handleNoType(Xrequired)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -66,7 +66,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(C, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, C)
+    beginClassDeclaration(class, null, null, C)
       handleNoType(C)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/non-nnbd/issue_40288_prime.dart.intertwined.expect b/pkg/front_end/parser_testcases/non-nnbd/issue_40288_prime.dart.intertwined.expect
index 06103bb..b03a234 100644
--- a/pkg/front_end/parser_testcases/non-nnbd/issue_40288_prime.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/non-nnbd/issue_40288_prime.dart.intertwined.expect
@@ -6,14 +6,14 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Xlate, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Xlate)
+        listener: beginClassDeclaration(class, null, null, Xlate)
         parseClass(Xlate, class, class, Xlate)
           parseClassHeaderOpt(Xlate, class, class)
             parseClassExtendsOpt(Xlate)
@@ -71,14 +71,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Xrequired, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Xrequired)
+        listener: beginClassDeclaration(class, null, null, Xrequired)
         parseClass(Xrequired, class, class, Xrequired)
           parseClassHeaderOpt(Xrequired, class, class)
             parseClassExtendsOpt(Xrequired)
@@ -136,14 +136,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(C, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, C)
+        listener: beginClassDeclaration(class, null, null, C)
         parseClass(C, class, class, C)
           parseClassHeaderOpt(C, class, class)
             parseClassExtendsOpt(C)
diff --git a/pkg/front_end/parser_testcases/non-nnbd/nullable_type_argument.dart.expect b/pkg/front_end/parser_testcases/non-nnbd/nullable_type_argument.dart.expect
index 6489670..5c1d956 100644
--- a/pkg/front_end/parser_testcases/non-nnbd/nullable_type_argument.dart.expect
+++ b/pkg/front_end/parser_testcases/non-nnbd/nullable_type_argument.dart.expect
@@ -12,7 +12,7 @@
         handleNoType(T)
       endTypeVariable(>, 0, null, null)
     endTypeVariables(<, >)
-    beginClassDeclaration(class, null, A)
+    beginClassDeclaration(class, null, null, A)
       handleNoType(>)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
@@ -27,7 +27,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(B, classOrMixinDeclaration)
     handleNoTypeVariables(implements)
-    beginClassDeclaration(class, null, B)
+    beginClassDeclaration(class, null, null, B)
       handleNoType(B)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/non-nnbd/nullable_type_argument.dart.intertwined.expect b/pkg/front_end/parser_testcases/non-nnbd/nullable_type_argument.dart.intertwined.expect
index 574de45..16f17a7 100644
--- a/pkg/front_end/parser_testcases/non-nnbd/nullable_type_argument.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/non-nnbd/nullable_type_argument.dart.intertwined.expect
@@ -6,9 +6,9 @@
     parseMetadataStar()
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(A, classOrMixinDeclaration)
@@ -21,7 +21,7 @@
         listener: handleNoType(T)
         listener: endTypeVariable(>, 0, null, null)
         listener: endTypeVariables(<, >)
-        listener: beginClassDeclaration(class, null, A)
+        listener: beginClassDeclaration(class, null, null, A)
         parseClass(>, class, class, A)
           parseClassHeaderOpt(>, class, class)
             parseClassExtendsOpt(>)
@@ -42,14 +42,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(B, classOrMixinDeclaration)
         listener: handleNoTypeVariables(implements)
-        listener: beginClassDeclaration(class, null, B)
+        listener: beginClassDeclaration(class, null, null, B)
         parseClass(B, class, class, B)
           parseClassHeaderOpt(B, class, class)
             parseClassExtendsOpt(B)
diff --git a/pkg/front_end/parser_testcases/non-nnbd/use_late_in_non_nnbd.dart.expect b/pkg/front_end/parser_testcases/non-nnbd/use_late_in_non_nnbd.dart.expect
index 025b95b..285a104 100644
--- a/pkg/front_end/parser_testcases/non-nnbd/use_late_in_non_nnbd.dart.expect
+++ b/pkg/front_end/parser_testcases/non-nnbd/use_late_in_non_nnbd.dart.expect
@@ -246,7 +246,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/non-nnbd/use_late_in_non_nnbd.dart.intertwined.expect b/pkg/front_end/parser_testcases/non-nnbd/use_late_in_non_nnbd.dart.intertwined.expect
index 4029ed4..3841fa7 100644
--- a/pkg/front_end/parser_testcases/non-nnbd/use_late_in_non_nnbd.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/non-nnbd/use_late_in_non_nnbd.dart.intertwined.expect
@@ -335,14 +335,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/parser_testcases/non-nnbd/use_required_in_non_nnbd.dart.expect b/pkg/front_end/parser_testcases/non-nnbd/use_required_in_non_nnbd.dart.expect
index 9835fbf..fb681d6 100644
--- a/pkg/front_end/parser_testcases/non-nnbd/use_required_in_non_nnbd.dart.expect
+++ b/pkg/front_end/parser_testcases/non-nnbd/use_required_in_non_nnbd.dart.expect
@@ -125,7 +125,7 @@
   beginClassOrMixinOrNamedMixinApplicationPrelude(class)
     handleIdentifier(Foo, classOrMixinDeclaration)
     handleNoTypeVariables({)
-    beginClassDeclaration(class, null, Foo)
+    beginClassDeclaration(class, null, null, Foo)
       handleNoType(Foo)
       handleClassExtends(null, 1)
       handleClassNoWithClause()
diff --git a/pkg/front_end/parser_testcases/non-nnbd/use_required_in_non_nnbd.dart.intertwined.expect b/pkg/front_end/parser_testcases/non-nnbd/use_required_in_non_nnbd.dart.intertwined.expect
index 8a6632f..f214652 100644
--- a/pkg/front_end/parser_testcases/non-nnbd/use_required_in_non_nnbd.dart.intertwined.expect
+++ b/pkg/front_end/parser_testcases/non-nnbd/use_required_in_non_nnbd.dart.intertwined.expect
@@ -253,14 +253,14 @@
     parseMetadataStar(})
       listener: beginMetadataStar(class)
       listener: endMetadataStar(0)
-    parseTopLevelKeywordDeclaration(}, class, Instance of 'DirectiveContext')
+    parseTopLevelKeywordDeclaration(}, class, null, Instance of 'DirectiveContext')
       parseClassDeclarationModifiers(}, class)
-      parseClassOrNamedMixinApplication(null, class)
+      parseClassOrNamedMixinApplication(null, null, class)
         listener: beginClassOrMixinOrNamedMixinApplicationPrelude(class)
         ensureIdentifier(class, classOrMixinDeclaration)
           listener: handleIdentifier(Foo, classOrMixinDeclaration)
         listener: handleNoTypeVariables({)
-        listener: beginClassDeclaration(class, null, Foo)
+        listener: beginClassDeclaration(class, null, null, Foo)
         parseClass(Foo, class, class, Foo)
           parseClassHeaderOpt(Foo, class, class)
             parseClassExtendsOpt(Foo)
diff --git a/pkg/front_end/test/class_hierarchy/class_hierarchy_test.dart b/pkg/front_end/test/class_hierarchy/class_hierarchy_test.dart
index 4acaf78..76f3281 100644
--- a/pkg/front_end/test/class_hierarchy/class_hierarchy_test.dart
+++ b/pkg/front_end/test/class_hierarchy/class_hierarchy_test.dart
@@ -8,7 +8,11 @@
 import 'package:_fe_analyzer_shared/src/testing/id_testing.dart';
 import 'package:front_end/src/testing/id_testing_helper.dart';
 import 'package:front_end/src/testing/id_testing_utils.dart';
-import 'package:front_end/src/fasta/kernel/class_hierarchy_builder.dart';
+import 'package:front_end/src/fasta/kernel/hierarchy/class_member.dart';
+import 'package:front_end/src/fasta/kernel/hierarchy/hierarchy_builder.dart';
+import 'package:front_end/src/fasta/kernel/hierarchy/hierarchy_node.dart';
+import 'package:front_end/src/fasta/kernel/hierarchy/members_builder.dart';
+import 'package:front_end/src/fasta/kernel/hierarchy/members_node.dart';
 import 'package:front_end/src/testing/id_extractor.dart';
 import 'package:kernel/ast.dart';
 import 'package:kernel/core_types.dart';
@@ -99,17 +103,20 @@
   CoreTypes get _coreTypes => _compilerResult.coreTypes!;
 
   ClassHierarchyBuilder get _classHierarchyBuilder =>
-      _compilerResult.kernelTargetForTesting!.loader.builderHierarchy;
+      _compilerResult.kernelTargetForTesting!.loader.hierarchyBuilder;
+
+  ClassMembersBuilder get _classMembersBuilder =>
+      _compilerResult.kernelTargetForTesting!.loader.membersBuilder;
 
   @override
   void computeForClass(Class node) {
     super.computeForClass(node);
-    ClassHierarchyNode classHierarchyNode =
-        _classHierarchyBuilder.getNodeFromClass(node);
-    ClassHierarchyNodeDataForTesting data = classHierarchyNode.dataForTesting!;
+    ClassMembersNode classMembersNode =
+        _classMembersBuilder.getNodeFromClass(node);
+    ClassHierarchyNodeDataForTesting data = classMembersNode.dataForTesting!;
     void addMember(ClassMember classMember,
         {required bool isSetter, required bool isClassMember}) {
-      Member member = classMember.getMember(_classHierarchyBuilder);
+      Member member = classMember.getMember(_classMembersBuilder);
       Member memberOrigin = member.memberSignatureOrigin ?? member;
       if (memberOrigin.enclosingClass == _coreTypes.objectClass) {
         return;
@@ -179,13 +186,13 @@
             features.add(Tag.abstractForwardingStub);
             features[Tag.type] = procedureType(member);
             features[Tag.covariance] =
-                classMember.getCovariance(_classHierarchyBuilder).toString();
+                classMember.getCovariance(_classMembersBuilder).toString();
             break;
           case ProcedureStubKind.ConcreteForwardingStub:
             features.add(Tag.concreteForwardingStub);
             features[Tag.type] = procedureType(member);
             features[Tag.covariance] =
-                classMember.getCovariance(_classHierarchyBuilder).toString();
+                classMember.getCovariance(_classMembersBuilder).toString();
             features[Tag.stubTarget] = memberQualifiedName(member.stubTarget!);
             break;
           case ProcedureStubKind.NoSuchMethodForwarder:
@@ -195,7 +202,7 @@
             features.add(Tag.memberSignature);
             features[Tag.type] = procedureType(member);
             features[Tag.covariance] =
-                classMember.getCovariance(_classHierarchyBuilder).toString();
+                classMember.getCovariance(_classMembersBuilder).toString();
             break;
           case ProcedureStubKind.AbstractMixinStub:
             features.add(Tag.abstractMixinStub);
@@ -211,23 +218,23 @@
           id, features, member);
     }
 
-    classHierarchyNode.classMemberMap
+    classMembersNode.classMemberMap
         .forEach((Name name, ClassMember classMember) {
       addMember(classMember, isSetter: false, isClassMember: true);
     });
-    classHierarchyNode.classSetterMap
+    classMembersNode.classSetterMap
         .forEach((Name name, ClassMember classMember) {
       addMember(classMember, isSetter: true, isClassMember: true);
     });
-    classHierarchyNode.interfaceMemberMap
+    classMembersNode.interfaceMemberMap
         ?.forEach((Name name, ClassMember classMember) {
-      if (!identical(classMember, classHierarchyNode.classMemberMap[name])) {
+      if (!identical(classMember, classMembersNode.classMemberMap[name])) {
         addMember(classMember, isSetter: false, isClassMember: false);
       }
     });
-    classHierarchyNode.interfaceSetterMap
+    classMembersNode.interfaceSetterMap
         ?.forEach((Name name, ClassMember classMember) {
-      if (!identical(classMember, classHierarchyNode.classSetterMap[name])) {
+      if (!identical(classMember, classMembersNode.classSetterMap[name])) {
         addMember(classMember, isSetter: true, isClassMember: false);
       }
     });
@@ -238,7 +245,9 @@
     Features features = new Features();
     ClassHierarchyNode classHierarchyNode =
         _classHierarchyBuilder.getNodeFromClass(node);
-    ClassHierarchyNodeDataForTesting data = classHierarchyNode.dataForTesting!;
+    ClassMembersNode classMembersNode =
+        _classMembersBuilder.getNodeFromClass(node);
+    ClassHierarchyNodeDataForTesting data = classMembersNode.dataForTesting!;
     classHierarchyNode.superclasses.forEach((Supertype supertype) {
       features.addElement(Tag.superclasses, supertypeToText(supertype));
     });
@@ -253,7 +262,7 @@
     }
     features[Tag.maxInheritancePath] =
         '${classHierarchyNode.maxInheritancePath}';
-    if (classHierarchyNode.hasNoSuchMethod) {
+    if (classMembersNode.hasNoSuchMethod) {
       features.add(Tag.hasNoSuchMethod);
     }
     return features;
diff --git a/pkg/front_end/test/fasta/generator_to_string_test.dart b/pkg/front_end/test/fasta/generator_to_string_test.dart
index 5fdfef0..f4790b9 100644
--- a/pkg/front_end/test/fasta/generator_to_string_test.dart
+++ b/pkg/front_end/test/fasta/generator_to_string_test.dart
@@ -84,18 +84,17 @@
     Expression index = new VariableGet(new VariableDeclaration("index"));
     UriTranslator uriTranslator = await c.options.getUriTranslator();
     SourceLibraryBuilder libraryBuilder = new SourceLibraryBuilder(
-        uri,
-        uri,
-        /*packageUri*/ null,
-        new ImplicitLanguageVersion(defaultLanguageVersion),
-        new KernelTarget(
+        importUri: uri,
+        fileUri: uri,
+        packageLanguageVersion:
+            new ImplicitLanguageVersion(defaultLanguageVersion),
+        loader: new KernelTarget(
                 const MockFileSystem(),
                 false,
                 new DillTarget(c.options.ticker, uriTranslator,
                     new NoneTarget(new TargetFlags())),
                 uriTranslator)
-            .loader,
-        null);
+            .loader);
     libraryBuilder.markLanguageVersionFinal();
     LoadLibraryBuilder loadLibraryBuilder =
         new LoadLibraryBuilder(libraryBuilder, dummyLibraryDependency, -1);
diff --git a/pkg/front_end/test/fasta/modular_suite.dart b/pkg/front_end/test/fasta/modular_suite.dart
new file mode 100644
index 0000000..8d7441e
--- /dev/null
+++ b/pkg/front_end/test/fasta/modular_suite.dart
@@ -0,0 +1,22 @@
+// Copyright (c) 2019, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE.md file.
+
+library fasta.test.weak_test;
+
+import 'testing/suite.dart';
+
+Future<FastaContext> createContext(
+    Chain suite, Map<String, String> environment) {
+  environment[COMPILATION_MODE] = CompileMode.modular.name;
+  return FastaContext.create(suite, environment);
+}
+
+void main(List<String> arguments) {
+  internalMain(arguments: arguments);
+}
+
+void internalMain(
+        {List<String> arguments = const [], int shards = 1, int shard = 0}) =>
+    runMe(arguments, createContext,
+        configurationPath: "../../testing.json", shard: shard, shards: shards);
diff --git a/pkg/front_end/test/fasta/sdk_test.dart b/pkg/front_end/test/fasta/sdk_test.dart
index c448d5d..400df69 100644
--- a/pkg/front_end/test/fasta/sdk_test.dart
+++ b/pkg/front_end/test/fasta/sdk_test.dart
@@ -8,7 +8,7 @@
 
 Future<FastaContext> createContext(
     Chain suite, Map<String, String> environment) {
-  environment[ENABLE_FULL_COMPILE] = "";
+  environment[COMPILATION_MODE] = CompileMode.full.name;
   environment["skipVm"] ??= "true";
   environment["onlyCrashes"] ??= "true";
   environment["ignoreExpectations"] ??= "true";
diff --git a/pkg/front_end/test/fasta/strong_suite.dart b/pkg/front_end/test/fasta/strong_suite.dart
index 538136d..8bb8640 100644
--- a/pkg/front_end/test/fasta/strong_suite.dart
+++ b/pkg/front_end/test/fasta/strong_suite.dart
@@ -8,7 +8,7 @@
 
 Future<FastaContext> createContext(
     Chain suite, Map<String, String> environment) {
-  environment[ENABLE_FULL_COMPILE] = "";
+  environment[COMPILATION_MODE] = CompileMode.full.name;
   environment['soundNullSafety'] = "true";
   return FastaContext.create(suite, environment);
 }
diff --git a/pkg/front_end/test/fasta/testing/suite.dart b/pkg/front_end/test/fasta/testing/suite.dart
index 3bbed42..f7221fd 100644
--- a/pkg/front_end/test/fasta/testing/suite.dart
+++ b/pkg/front_end/test/fasta/testing/suite.dart
@@ -66,12 +66,12 @@
 import 'package:front_end/src/fasta/incremental_compiler.dart'
     show IncrementalCompiler;
 
-import 'package:front_end/src/fasta/kernel/class_hierarchy_builder.dart'
-    show ClassHierarchyNode;
-
-import 'package:front_end/src/fasta/kernel/class_hierarchy_builder.dart'
+import 'package:front_end/src/fasta/kernel/hierarchy/hierarchy_builder.dart'
     show ClassHierarchyBuilder;
 
+import 'package:front_end/src/fasta/kernel/hierarchy/hierarchy_node.dart'
+    show ClassHierarchyNode;
+
 import 'package:front_end/src/fasta/kernel/kernel_target.dart'
     show KernelTarget;
 
@@ -171,7 +171,7 @@
 
 export 'package:testing/testing.dart' show Chain, runMe;
 
-const String ENABLE_FULL_COMPILE = " full compile ";
+const String COMPILATION_MODE = " compilation mode ";
 
 const String UPDATE_EXPECTATIONS = "updateExpectations";
 const String UPDATE_COMMENTS = "updateComments";
@@ -378,55 +378,61 @@
       this.skipVm,
       this.semiFuzz,
       bool kernelTextSerialization,
-      bool fullCompile,
+      CompileMode compileMode,
       this.verify,
       this.soundNullSafety)
       : steps = <Step>[
-          new Outline(fullCompile, updateComments: updateComments),
+          new Outline(compileMode, updateComments: updateComments),
           const Print(),
-          new Verify(fullCompile)
+          new Verify(compileMode)
         ] {
-    String fullPrefix;
-    String outlinePrefix;
+    String prefix;
+    String infix;
     if (soundNullSafety) {
-      fullPrefix = '.strong';
-      outlinePrefix = '.strong.outline';
+      prefix = '.strong';
     } else {
-      fullPrefix = '.weak';
-      outlinePrefix = '.weak.outline';
+      prefix = '.weak';
+    }
+    switch (compileMode) {
+      case CompileMode.outline:
+        infix = '.outline';
+        break;
+      case CompileMode.modular:
+        infix = '.modular';
+        break;
+      case CompileMode.full:
+        infix = '';
+        break;
     }
 
-    if (!fullCompile) {
-      // If not doing a full compile this is the only expect file so we run the
-      // extra constant evaluation now. If we do a full compilation, we'll do
-      // if after the transformation. That also ensures we don't get the same
-      // 'extra constant evaluation' output twice (in .transformed and not).
+    if (compileMode == CompileMode.outline) {
+      // If doing an outline compile, this is the only expect file so we run the
+      // extra constant evaluation now. If we do a full or modular compilation,
+      // we'll do if after the transformation. That also ensures we don't get
+      // the same 'extra constant evaluation' output twice (in .transformed and
+      // not).
       steps.add(const StressConstantEvaluatorStep());
     }
     if (!ignoreExpectations) {
-      steps.add(new MatchExpectation(
-          fullCompile ? "$fullPrefix.expect" : "$outlinePrefix.expect",
-          serializeFirst: false,
-          isLastMatchStep: false));
-      steps.add(new MatchExpectation(
-          fullCompile ? "$fullPrefix.expect" : "$outlinePrefix.expect",
-          serializeFirst: true,
-          isLastMatchStep: true));
+      steps.add(new MatchExpectation("$prefix$infix.expect",
+          serializeFirst: false, isLastMatchStep: false));
+      steps.add(new MatchExpectation("$prefix$infix.expect",
+          serializeFirst: true, isLastMatchStep: true));
     }
     steps.add(const TypeCheck());
     steps.add(const EnsureNoErrors());
     if (kernelTextSerialization) {
       steps.add(const KernelTextSerialization());
     }
-    if (fullCompile) {
+    if (compileMode == CompileMode.full) {
       steps.add(const Transform());
-      steps.add(const Verify(true));
+      steps.add(const Verify(CompileMode.full));
       steps.add(const StressConstantEvaluatorStep());
       if (!ignoreExpectations) {
-        steps.add(new MatchExpectation("$fullPrefix.transformed.expect",
+        steps.add(new MatchExpectation("$prefix$infix.transformed.expect",
             serializeFirst: false, isLastMatchStep: updateExpectations));
         if (!updateExpectations) {
-          steps.add(new MatchExpectation("$fullPrefix.transformed.expect",
+          steps.add(new MatchExpectation("$prefix$infix.transformed.expect",
               serializeFirst: true, isLastMatchStep: true));
         }
       }
@@ -767,7 +773,7 @@
       "verify",
       KERNEL_TEXT_SERIALIZATION,
       "platformBinaries",
-      ENABLE_FULL_COMPILE,
+      COMPILATION_MODE,
     };
     checkEnvironment(environment, knownEnvironmentKeys);
 
@@ -815,7 +821,7 @@
         skipVm,
         semiFuzz,
         kernelTextSerialization,
-        environment.containsKey(ENABLE_FULL_COMPILE),
+        compileModeFromName(environment[COMPILATION_MODE]),
         verify,
         soundNullSafety));
   }
@@ -1777,13 +1783,15 @@
 }
 
 Set<Uri> createUserLibrariesImportUriSet(
-    Component component, UriTranslator uriTranslator) {
+    Component component, UriTranslator uriTranslator,
+    {Set<Library> excludedLibraries: const {}}) {
   Set<Uri> knownUris =
       component.libraries.map((Library library) => library.importUri).toSet();
   Set<Uri> userLibraries = component.libraries
       .where((Library library) =>
           library.importUri.scheme != 'dart' &&
-          library.importUri.scheme != 'package')
+          library.importUri.scheme != 'package' &&
+          !excludedLibraries.contains(library))
       .map((Library library) => library.importUri)
       .toSet();
   // Mark custom "dart:" libraries defined in the test-specific libraries.json
@@ -1797,20 +1805,48 @@
   return userLibraries.intersection(knownUris);
 }
 
-class Outline extends Step<TestDescription, ComponentResult, FastaContext> {
-  final bool fullCompile;
+enum CompileMode {
+  /// Compiles only the outline of the test and its linked dependencies.
+  outline,
 
-  const Outline(this.fullCompile, {this.updateComments: false});
+  /// Fully compiles the test but compiles only the outline of its linked
+  /// dependencies.
+  ///
+  /// This mimics how modular compilation is performed with dartdevc.
+  modular,
+
+  /// Fully compiles the test and its linked dependencies.
+  full,
+}
+
+CompileMode compileModeFromName(String? name) {
+  for (CompileMode mode in CompileMode.values) {
+    if (name == mode.name) {
+      return mode;
+    }
+  }
+  return CompileMode.outline;
+}
+
+class Outline extends Step<TestDescription, ComponentResult, FastaContext> {
+  final CompileMode compileMode;
+
+  const Outline(this.compileMode, {this.updateComments: false});
 
   final bool updateComments;
 
   @override
   String get name {
-    return fullCompile ? "compile" : "outline";
+    switch (compileMode) {
+      case CompileMode.outline:
+        return "outline";
+      case CompileMode.modular:
+        return "modular";
+      case CompileMode.full:
+        return "compile";
+    }
   }
 
-  bool get isCompiler => fullCompile;
-
   @override
   Future<Result<ComponentResult>> run(
       TestDescription description, FastaContext context) async {
@@ -1839,7 +1875,7 @@
           compilationSetup.errors.addAll(compilationSetup.testOptions.errors!);
         }
         Component p = (await sourceTarget.buildOutlines())!;
-        if (fullCompile) {
+        if (compileMode == CompileMode.full) {
           p = (await sourceTarget.buildComponent(
               verify: compilationSetup.folderOptions.noVerify
                   ? false
@@ -1885,6 +1921,13 @@
       if (description.uri.pathSegments.last.endsWith(".no_link.dart")) {
         alsoAppend = null;
       }
+
+      Set<Library>? excludedLibraries;
+      if (compileMode == CompileMode.modular) {
+        excludedLibraries = alsoAppend?.libraries.toSet();
+      }
+      excludedLibraries ??= const {};
+
       KernelTarget sourceTarget = await outlineInitialization(context,
           description, compilationSetup.options, <Uri>[description.uri],
           alsoAppend: alsoAppend);
@@ -1893,9 +1936,10 @@
       await instrumentation.loadExpectations(description.uri);
       sourceTarget.loader.instrumentation = instrumentation;
       Component p = (await sourceTarget.buildOutlines())!;
-      Set<Uri> userLibraries =
-          createUserLibrariesImportUriSet(p, sourceTarget.uriTranslator);
-      if (fullCompile) {
+      Set<Uri> userLibraries = createUserLibrariesImportUriSet(
+          p, sourceTarget.uriTranslator,
+          excludedLibraries: excludedLibraries);
+      if (compileMode != CompileMode.outline) {
         p = (await sourceTarget.buildComponent(
             verify: compilationSetup.folderOptions.noVerify
                 ? false
@@ -1998,9 +2042,9 @@
 }
 
 class Verify extends Step<ComponentResult, ComponentResult, FastaContext> {
-  final bool fullCompile;
+  final CompileMode compileMode;
 
-  const Verify(this.fullCompile);
+  const Verify(this.compileMode);
 
   @override
   String get name => "verify";
@@ -2031,7 +2075,7 @@
       compilerContext.uriToSource.addAll(component.uriToSource);
       List<LocatedMessage> verificationErrors = verifyComponent(
           component, result.options.target,
-          isOutline: !fullCompile, skipPlatform: true);
+          isOutline: compileMode == CompileMode.outline, skipPlatform: true);
       assert(verificationErrors.isEmpty || messages.isNotEmpty);
       if (messages.isEmpty) {
         return pass(result);
@@ -2148,7 +2192,7 @@
     Uri uri =
         component.uriToSource.keys.firstWhere((uri) => uri.scheme == "file");
     KernelTarget target = result.sourceTarget;
-    ClassHierarchyBuilder hierarchy = target.loader.builderHierarchy;
+    ClassHierarchyBuilder hierarchy = target.loader.hierarchyBuilder;
     StringBuffer sb = new StringBuffer();
     for (ClassHierarchyNode node in hierarchy.nodes.values) {
       sb.writeln(node);
diff --git a/pkg/front_end/test/fasta/text_serialization_suite.dart b/pkg/front_end/test/fasta/text_serialization_suite.dart
index cddceac..eda34ee 100644
--- a/pkg/front_end/test/fasta/text_serialization_suite.dart
+++ b/pkg/front_end/test/fasta/text_serialization_suite.dart
@@ -8,7 +8,7 @@
 
 Future<FastaContext> createContext(
     Chain suite, Map<String, String> environment) {
-  environment[ENABLE_FULL_COMPILE] = "";
+  environment[COMPILATION_MODE] = CompileMode.full.name;
   environment[KERNEL_TEXT_SERIALIZATION] = "";
   return FastaContext.create(suite, environment);
 }
diff --git a/pkg/front_end/test/fasta/types/dill_hierachy_test.dart b/pkg/front_end/test/fasta/types/dill_hierachy_test.dart
deleted file mode 100644
index cf2e491..0000000
--- a/pkg/front_end/test/fasta/types/dill_hierachy_test.dart
+++ /dev/null
@@ -1,136 +0,0 @@
-// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-import "package:async_helper/async_helper.dart" show asyncTest;
-
-import "package:expect/expect.dart" show Expect;
-
-import "package:kernel/ast.dart" show Class, Component, Library;
-
-import "package:kernel/core_types.dart" show CoreTypes;
-
-import "package:kernel/target/targets.dart" show NoneTarget, TargetFlags;
-
-import 'package:kernel/testing/type_parser_environment.dart'
-    show parseComponent;
-
-import "package:front_end/src/api_prototype/compiler_options.dart"
-    show CompilerOptions;
-
-import "package:front_end/src/base/processed_options.dart"
-    show ProcessedOptions;
-
-import "package:front_end/src/fasta/builder/class_builder.dart";
-
-import "package:front_end/src/fasta/compiler_context.dart" show CompilerContext;
-
-import "package:front_end/src/fasta/dill/dill_loader.dart" show DillLoader;
-
-import "package:front_end/src/fasta/dill/dill_target.dart" show DillTarget;
-
-import "package:front_end/src/fasta/kernel/class_hierarchy_builder.dart"
-    show ClassHierarchyBuilder;
-
-import "package:front_end/src/fasta/ticker.dart" show Ticker;
-
-const String expectedHierarchy = """
-Object:
-  superclasses:
-  interfaces:
-  classMembers:
-  classSetters:
-
-A:
-  superclasses:
-    Object
-  interfaces:
-  classMembers:
-  classSetters:
-
-B:
-  Longest path to Object: 2
-  superclasses:
-    Object
-  interfaces: A
-  classMembers:
-  classSetters:
-  interfaceMembers:
-  interfaceSetters:
-
-C:
-  Longest path to Object: 2
-  superclasses:
-    Object
-  interfaces: A
-  classMembers:
-  classSetters:
-  interfaceMembers:
-  interfaceSetters:
-
-D:
-  Longest path to Object: 3
-  superclasses:
-    Object
-  interfaces: B<T>, A, C<U>
-  classMembers:
-  classSetters:
-  interfaceMembers:
-  interfaceSetters:
-
-E:
-  Longest path to Object: 4
-  superclasses:
-    Object
-  interfaces: D<int,double>, B<int>, A, C<double>
-  classMembers:
-  classSetters:
-  interfaceMembers:
-  interfaceSetters:
-
-F:
-  Longest path to Object: 4
-  superclasses:
-    Object
-  interfaces: D<int,bool>, B<int>, A, C<bool>
-  classMembers:
-  classSetters:
-  interfaceMembers:
-  interfaceSetters:
-""";
-
-void main() {
-  final Ticker ticker = new Ticker(isVerbose: false);
-  final Component component = parseComponent("""
-class A;
-class B<T> implements A;
-class C<U> implements A;
-class D<T, U> implements B<T>, C<U>;
-class E implements D<int, double>;
-class F implements D<int, bool>;""",
-      Uri.parse("org-dartlang-test:///library.dart"));
-
-  final CompilerContext context = new CompilerContext(new ProcessedOptions(
-      options: new CompilerOptions()
-        ..packagesFileUri = Uri.base.resolve(".packages")));
-
-  asyncTest(() => context.runInContext<void>((_) async {
-        DillTarget target = new DillTarget(
-            ticker,
-            await context.options.getUriTranslator(),
-            new NoneTarget(new TargetFlags()));
-        final DillLoader loader = target.loader;
-        loader.appendLibraries(component);
-        target.buildOutlines();
-        ClassBuilder objectClass = loader.coreLibrary
-            .lookupLocalMember("Object", required: true) as ClassBuilder;
-        ClassHierarchyBuilder hierarchy = new ClassHierarchyBuilder(
-            objectClass, loader, new CoreTypes(component));
-        Library library = component.libraries.last;
-        for (Class cls in library.classes) {
-          hierarchy.getNodeFromClass(cls);
-        }
-        Expect.stringEquals(
-            expectedHierarchy, hierarchy.nodes.values.join("\n"));
-      }));
-}
diff --git a/pkg/front_end/test/fasta/types/dill_hierarchy_test.dart b/pkg/front_end/test/fasta/types/dill_hierarchy_test.dart
new file mode 100644
index 0000000..55076d6
--- /dev/null
+++ b/pkg/front_end/test/fasta/types/dill_hierarchy_test.dart
@@ -0,0 +1,112 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import "package:async_helper/async_helper.dart" show asyncTest;
+
+import "package:expect/expect.dart" show Expect;
+
+import "package:kernel/ast.dart" show Class, Component, Library;
+
+import "package:kernel/core_types.dart" show CoreTypes;
+
+import "package:kernel/target/targets.dart" show NoneTarget, TargetFlags;
+
+import 'package:kernel/testing/type_parser_environment.dart'
+    show parseComponent;
+
+import "package:front_end/src/api_prototype/compiler_options.dart"
+    show CompilerOptions;
+
+import "package:front_end/src/base/processed_options.dart"
+    show ProcessedOptions;
+
+import "package:front_end/src/fasta/builder/class_builder.dart";
+
+import "package:front_end/src/fasta/compiler_context.dart" show CompilerContext;
+
+import "package:front_end/src/fasta/dill/dill_loader.dart" show DillLoader;
+
+import "package:front_end/src/fasta/dill/dill_target.dart" show DillTarget;
+
+import "package:front_end/src/fasta/kernel/hierarchy/hierarchy_builder.dart"
+    show ClassHierarchyBuilder;
+
+import "package:front_end/src/fasta/ticker.dart" show Ticker;
+
+const String expectedHierarchy = """
+Object:
+  superclasses:
+  interfaces:
+
+A:
+  superclasses:
+    Object
+  interfaces:
+
+B:
+  Longest path to Object: 2
+  superclasses:
+    Object
+  interfaces: A
+
+C:
+  Longest path to Object: 2
+  superclasses:
+    Object
+  interfaces: A
+
+D:
+  Longest path to Object: 3
+  superclasses:
+    Object
+  interfaces: B<T>, A, C<U>
+
+E:
+  Longest path to Object: 4
+  superclasses:
+    Object
+  interfaces: D<int,double>, B<int>, A, C<double>
+
+F:
+  Longest path to Object: 4
+  superclasses:
+    Object
+  interfaces: D<int,bool>, B<int>, A, C<bool>
+""";
+
+void main() {
+  final Ticker ticker = new Ticker(isVerbose: false);
+  final Component component = parseComponent("""
+class A;
+class B<T> implements A;
+class C<U> implements A;
+class D<T, U> implements B<T>, C<U>;
+class E implements D<int, double>;
+class F implements D<int, bool>;""",
+      Uri.parse("org-dartlang-test:///library.dart"));
+
+  final CompilerContext context = new CompilerContext(new ProcessedOptions(
+      options: new CompilerOptions()
+        ..packagesFileUri = Uri.base.resolve(".packages")));
+
+  asyncTest(() => context.runInContext<void>((_) async {
+        DillTarget target = new DillTarget(
+            ticker,
+            await context.options.getUriTranslator(),
+            new NoneTarget(new TargetFlags()));
+        final DillLoader loader = target.loader;
+        loader.appendLibraries(component);
+        target.buildOutlines();
+        ClassBuilder objectClass = loader.coreLibrary
+            .lookupLocalMember("Object", required: true) as ClassBuilder;
+        ClassHierarchyBuilder hierarchy = new ClassHierarchyBuilder(
+            objectClass, loader, new CoreTypes(component));
+        Library library = component.libraries.last;
+        for (Class cls in library.classes) {
+          hierarchy.getNodeFromClass(cls);
+        }
+        Expect.stringEquals(
+            expectedHierarchy, hierarchy.nodes.values.join("\n"));
+      }));
+}
diff --git a/pkg/front_end/test/fasta/types/fasta_legacy_upper_bound_test.dart b/pkg/front_end/test/fasta/types/fasta_legacy_upper_bound_test.dart
index cc4493a..618c014 100644
--- a/pkg/front_end/test/fasta/types/fasta_legacy_upper_bound_test.dart
+++ b/pkg/front_end/test/fasta/types/fasta_legacy_upper_bound_test.dart
@@ -20,7 +20,7 @@
 
 import "package:front_end/src/fasta/dill/dill_target.dart" show DillTarget;
 
-import "package:front_end/src/fasta/kernel/class_hierarchy_builder.dart"
+import "package:front_end/src/fasta/kernel/hierarchy/hierarchy_builder.dart"
     show ClassHierarchyBuilder;
 
 import "package:front_end/src/fasta/ticker.dart" show Ticker;
diff --git a/pkg/front_end/test/fasta/types/fasta_types_test.dart b/pkg/front_end/test/fasta/types/fasta_types_test.dart
index ecff945..55095c7 100644
--- a/pkg/front_end/test/fasta/types/fasta_types_test.dart
+++ b/pkg/front_end/test/fasta/types/fasta_types_test.dart
@@ -29,7 +29,7 @@
 
 import "package:front_end/src/fasta/dill/dill_target.dart" show DillTarget;
 
-import "package:front_end/src/fasta/kernel/class_hierarchy_builder.dart"
+import "package:front_end/src/fasta/kernel/hierarchy/hierarchy_builder.dart"
     show ClassHierarchyBuilder;
 
 import "package:front_end/src/fasta/ticker.dart" show Ticker;
diff --git a/pkg/front_end/test/fasta/types/subtypes_benchmark.dart b/pkg/front_end/test/fasta/types/subtypes_benchmark.dart
index d3c0a09..165313e 100644
--- a/pkg/front_end/test/fasta/types/subtypes_benchmark.dart
+++ b/pkg/front_end/test/fasta/types/subtypes_benchmark.dart
@@ -34,7 +34,7 @@
 
 import "package:front_end/src/fasta/dill/dill_target.dart" show DillTarget;
 
-import "package:front_end/src/fasta/kernel/class_hierarchy_builder.dart"
+import "package:front_end/src/fasta/kernel/hierarchy/hierarchy_builder.dart"
     show ClassHierarchyBuilder;
 
 import "package:front_end/src/fasta/ticker.dart" show Ticker;
diff --git a/pkg/front_end/test/fasta/weak_suite.dart b/pkg/front_end/test/fasta/weak_suite.dart
index 1ce80c58..52fd4d8 100644
--- a/pkg/front_end/test/fasta/weak_suite.dart
+++ b/pkg/front_end/test/fasta/weak_suite.dart
@@ -8,7 +8,7 @@
 
 Future<FastaContext> createContext(
     Chain suite, Map<String, String> environment) {
-  environment[ENABLE_FULL_COMPILE] = "";
+  environment[COMPILATION_MODE] = CompileMode.full.name;
   return FastaContext.create(suite, environment);
 }
 
diff --git a/pkg/front_end/test/id_tests/inheritance_test.dart b/pkg/front_end/test/id_tests/inheritance_test.dart
index 11dc8bc..78f9bf5 100644
--- a/pkg/front_end/test/id_tests/inheritance_test.dart
+++ b/pkg/front_end/test/id_tests/inheritance_test.dart
@@ -7,7 +7,8 @@
 import 'package:_fe_analyzer_shared/src/testing/id.dart';
 import 'package:_fe_analyzer_shared/src/testing/id_testing.dart';
 import 'package:front_end/src/api_prototype/experimental_flags.dart';
-import 'package:front_end/src/fasta/kernel/class_hierarchy_builder.dart';
+import 'package:front_end/src/fasta/kernel/hierarchy/hierarchy_builder.dart';
+import 'package:front_end/src/fasta/kernel/hierarchy/hierarchy_node.dart';
 import 'package:front_end/src/testing/id_extractor.dart';
 import 'package:front_end/src/testing/id_testing_helper.dart';
 import 'package:front_end/src/testing/id_testing_utils.dart';
@@ -95,7 +96,7 @@
   CoreTypes get _coreTypes => _compilerResult.coreTypes!;
 
   ClassHierarchyBuilder get _classHierarchyBuilder =>
-      _compilerResult.kernelTargetForTesting!.loader.builderHierarchy;
+      _compilerResult.kernelTargetForTesting!.loader.hierarchyBuilder;
 
   @override
   String computeLibraryValue(Id id, Library node) {
diff --git a/pkg/front_end/test/macros/data/pkgs/macro/lib/macro.dart b/pkg/front_end/test/macros/data/pkgs/macro/lib/macro.dart
index bfe0285..f79b175 100644
--- a/pkg/front_end/test/macros/data/pkgs/macro/lib/macro.dart
+++ b/pkg/front_end/test/macros/data/pkgs/macro/lib/macro.dart
@@ -4,15 +4,15 @@
 
 import 'package:macro_builder/macro_builder.dart';
 
-class Macro1 implements Macro {
+macro class Macro1 implements Macro {
   const Macro1();
 }
 
-class Macro2 implements Macro {
+macro class Macro2 implements Macro {
   const Macro2();
 }
 
-class Macro3 implements Macro {
+macro class Macro3 implements Macro {
   const Macro3();
 }
 
diff --git a/pkg/front_end/test/macros/data/tests/declare_macro.dart b/pkg/front_end/test/macros/data/tests/declare_macro.dart
index 5d396f7..e6d329e 100644
--- a/pkg/front_end/test/macros/data/tests/declare_macro.dart
+++ b/pkg/front_end/test/macros/data/tests/declare_macro.dart
@@ -12,6 +12,6 @@
 
 import 'package:macro_builder/macro_builder.dart';
 
-class MyMacro implements Macro {}
+macro class MyMacro implements Macro {}
 
 void main() {}
diff --git a/pkg/front_end/test/macros/data/tests/declare_vs_apply/macro_lib.dart b/pkg/front_end/test/macros/data/tests/declare_vs_apply/macro_lib.dart
index 149d512..f1aac83 100644
--- a/pkg/front_end/test/macros/data/tests/declare_vs_apply/macro_lib.dart
+++ b/pkg/front_end/test/macros/data/tests/declare_vs_apply/macro_lib.dart
@@ -10,6 +10,6 @@
 import 'package:macro_builder/macro_builder.dart';
 import 'macro_lib_dep.dart';
 
-class Macro1 extends MacroBase implements Macro {
+macro class Macro1 extends MacroBase implements Macro {
   const Macro1();
 }
diff --git a/pkg/front_end/test/macros/data/tests/import_macro_source/macro_lib.dart b/pkg/front_end/test/macros/data/tests/import_macro_source/macro_lib.dart
index a05f387..c08cbcd 100644
--- a/pkg/front_end/test/macros/data/tests/import_macro_source/macro_lib.dart
+++ b/pkg/front_end/test/macros/data/tests/import_macro_source/macro_lib.dart
@@ -9,6 +9,6 @@
 
 import 'package:macro_builder/macro_builder.dart';
 
-class Macro1 implements Macro {
+macro class Macro1 implements Macro {
   const Macro1();
 }
diff --git a/pkg/front_end/test/macros/data/tests/macro_declarations.dart b/pkg/front_end/test/macros/data/tests/macro_declarations.dart
index 872dad84..f5f5a5f 100644
--- a/pkg/front_end/test/macros/data/tests/macro_declarations.dart
+++ b/pkg/front_end/test/macros/data/tests/macro_declarations.dart
@@ -13,25 +13,47 @@
   ImplementsAlias,
   Mixin,
   MixinAlias,
-  _Mixin&Object&Macro,
-  _MixinAlias&Object&Alias],
+  NamedMixin1,
+  NamedMixin2],
  macrosAreAvailable
 */
 
 import 'package:macro_builder/macro_builder.dart';
 
-class Extends extends Macro {}
+macro class Extends extends Macro {}
 
-class Implements implements Macro {}
+macro class Implements implements Macro {}
 
-class Mixin with Macro {}
+macro class Mixin with Macro {}
+
+mixin _Mixin {}
+
+macro class NamedMixin1 = Macro with _Mixin;
+
+macro class NamedMixin2 = Object with Macro;
 
 typedef Alias = Macro;
 
-class ExtendsAlias extends Alias {}
+macro class ExtendsAlias extends Alias {}
 
-class ImplementsAlias implements Alias {}
+macro class ImplementsAlias implements Alias {}
 
-class MixinAlias with Alias {}
+macro class MixinAlias with Alias {}
+
+class ExtendsNoKeyword extends Macro {}
+
+class ImplementsNoKeyword implements Macro {}
+
+class MixinNoKeyword with Macro {}
+
+class ExtendsAliasNoKeyword extends Alias {}
+
+class ImplementsAliasNoKeyword implements Alias {}
+
+class MixinAliasNoKeyword with Alias {}
+
+class NamedMixin1NoKeyword = Macro with _Mixin;
+
+class NamedMixin2NoKeyword = Object with Macro;
 
 void main() {}
diff --git a/pkg/front_end/test/macros/data/tests/multiple_macros/macro_lib1.dart b/pkg/front_end/test/macros/data/tests/multiple_macros/macro_lib1.dart
index a05f387..c08cbcd 100644
--- a/pkg/front_end/test/macros/data/tests/multiple_macros/macro_lib1.dart
+++ b/pkg/front_end/test/macros/data/tests/multiple_macros/macro_lib1.dart
@@ -9,6 +9,6 @@
 
 import 'package:macro_builder/macro_builder.dart';
 
-class Macro1 implements Macro {
+macro class Macro1 implements Macro {
   const Macro1();
 }
diff --git a/pkg/front_end/test/macros/data/tests/multiple_macros/macro_lib2a.dart b/pkg/front_end/test/macros/data/tests/multiple_macros/macro_lib2a.dart
index 967801f..729e7f1 100644
--- a/pkg/front_end/test/macros/data/tests/multiple_macros/macro_lib2a.dart
+++ b/pkg/front_end/test/macros/data/tests/multiple_macros/macro_lib2a.dart
@@ -9,6 +9,6 @@
 
 import 'package:macro_builder/macro_builder.dart';
 
-class Macro2a implements Macro {
+macro class Macro2a implements Macro {
   const Macro2a();
 }
diff --git a/pkg/front_end/test/macros/data/tests/multiple_macros/macro_lib2b.dart b/pkg/front_end/test/macros/data/tests/multiple_macros/macro_lib2b.dart
index b9bc7d2..df143f5 100644
--- a/pkg/front_end/test/macros/data/tests/multiple_macros/macro_lib2b.dart
+++ b/pkg/front_end/test/macros/data/tests/multiple_macros/macro_lib2b.dart
@@ -16,6 +16,6 @@
  appliedMacros=[Macro2a],
  macrosAreApplied
 */
-class Macro2b implements Macro {
+macro class Macro2b implements Macro {
   const Macro2b();
 }
diff --git a/pkg/front_end/test/macros/data/tests/use_macro_source/macro_lib.dart b/pkg/front_end/test/macros/data/tests/use_macro_source/macro_lib.dart
index 3f926a8..f3767a5 100644
--- a/pkg/front_end/test/macros/data/tests/use_macro_source/macro_lib.dart
+++ b/pkg/front_end/test/macros/data/tests/use_macro_source/macro_lib.dart
@@ -11,11 +11,11 @@
 
 import 'package:macro_builder/macro_builder.dart';
 
-class Macro1 implements Macro {
+macro class Macro1 implements Macro {
   const Macro1();
 }
 
-class Macro2 implements Macro {
+macro class Macro2 implements Macro {
   const Macro2();
 }
 
diff --git a/pkg/front_end/test/macros/macro_test.dart b/pkg/front_end/test/macros/macro_test.dart
index 82fe62d..c1aa33e 100644
--- a/pkg/front_end/test/macros/macro_test.dart
+++ b/pkg/front_end/test/macros/macro_test.dart
@@ -8,6 +8,7 @@
 import 'package:_fe_analyzer_shared/src/testing/id_testing.dart';
 
 import 'package:_fe_analyzer_shared/src/testing/features.dart';
+import 'package:front_end/src/api_prototype/experimental_flags.dart';
 import 'package:front_end/src/fasta/kernel/macro.dart';
 import 'package:front_end/src/testing/id_testing_helper.dart';
 import 'package:kernel/ast.dart';
@@ -23,6 +24,7 @@
       onFailure: onFailure,
       runTest: runTestFor(const MacroDataComputer(), [
         new TestConfig(cfeMarker, 'cfe',
+            explicitExperimentalFlags: {ExperimentalFlag.macros: true},
             packageConfigUri:
                 Platform.script.resolve('data/package_config.json'))
       ]));
diff --git a/pkg/front_end/test/parser_test_listener.dart b/pkg/front_end/test/parser_test_listener.dart
index f90c7fa..65979d9 100644
--- a/pkg/front_end/test/parser_test_listener.dart
+++ b/pkg/front_end/test/parser_test_listener.dart
@@ -199,11 +199,17 @@
   }
 
   @override
-  void beginClassDeclaration(Token begin, Token? abstractToken, Token name) {
+  void beginClassDeclaration(
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {
     seen(begin);
     seen(abstractToken);
+    seen(macroToken);
     seen(name);
-    doPrint('beginClassDeclaration(' '$begin, ' '$abstractToken, ' '$name)');
+    doPrint('beginClassDeclaration('
+        '$begin, '
+        '$abstractToken, '
+        '$macroToken, '
+        '$name)');
     indent++;
   }
 
@@ -1017,12 +1023,16 @@
 
   @override
   void beginNamedMixinApplication(
-      Token begin, Token? abstractToken, Token name) {
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {
     seen(begin);
     seen(abstractToken);
+    seen(macroToken);
     seen(name);
-    doPrint(
-        'beginNamedMixinApplication(' '$begin, ' '$abstractToken, ' '$name)');
+    doPrint('beginNamedMixinApplication('
+        '$begin, '
+        '$abstractToken, '
+        '$macroToken, '
+        '$name)');
     indent++;
   }
 
@@ -2660,16 +2670,25 @@
 
   @override
   void handleCommentReference(
-      Token? newKeyword, Token? prefix, Token? period, Token token) {
+      Token? newKeyword,
+      Token? firstToken,
+      Token? firstPeriod,
+      Token? secondToken,
+      Token? secondPeriod,
+      Token thirdToken) {
     seen(newKeyword);
-    seen(prefix);
-    seen(period);
-    seen(token);
+    seen(firstToken);
+    seen(firstPeriod);
+    seen(secondToken);
+    seen(secondPeriod);
+    seen(thirdToken);
     doPrint('handleCommentReference('
         '$newKeyword, '
-        '$prefix, '
-        '$period, '
-        '$token)');
+        '$firstToken, '
+        '$firstPeriod, '
+        '$secondToken, '
+        '$secondPeriod, '
+        '$thirdToken)');
   }
 
   @override
diff --git a/pkg/front_end/test/parser_test_listener_creator.dart b/pkg/front_end/test/parser_test_listener_creator.dart
index fab26f9..61ba320 100644
--- a/pkg/front_end/test/parser_test_listener_creator.dart
+++ b/pkg/front_end/test/parser_test_listener_creator.dart
@@ -126,7 +126,8 @@
   ParserCreatorListener(this.out);
 
   @override
-  void beginClassDeclaration(Token begin, Token? abstractToken, Token name) {
+  void beginClassDeclaration(
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {
     if (name.lexeme == "Listener") insideListenerClass = true;
   }
 
diff --git a/pkg/front_end/test/parser_test_parser.dart b/pkg/front_end/test/parser_test_parser.dart
index 139220a..9a545e4 100644
--- a/pkg/front_end/test/parser_test_parser.dart
+++ b/pkg/front_end/test/parser_test_parser.dart
@@ -189,15 +189,16 @@
   }
 
   @override
-  Token parseTopLevelKeywordDeclaration(
-      Token start, Token keyword, DirectiveContext? directiveState) {
+  Token parseTopLevelKeywordDeclaration(Token start, Token keyword,
+      Token? macroToken, DirectiveContext? directiveState) {
     doPrint('parseTopLevelKeywordDeclaration('
         '$start, '
         '$keyword, '
+        '$macroToken, '
         '$directiveState)');
     indent++;
-    var result =
-        super.parseTopLevelKeywordDeclaration(start, keyword, directiveState);
+    var result = super.parseTopLevelKeywordDeclaration(
+        start, keyword, macroToken, directiveState);
     indent--;
     return result;
   }
@@ -583,13 +584,14 @@
 
   @override
   Token parseClassOrNamedMixinApplication(
-      Token? abstractToken, Token classKeyword) {
+      Token? abstractToken, Token? macroToken, Token classKeyword) {
     doPrint('parseClassOrNamedMixinApplication('
         '$abstractToken, '
+        '$macroToken, '
         '$classKeyword)');
     indent++;
-    var result =
-        super.parseClassOrNamedMixinApplication(abstractToken, classKeyword);
+    var result = super.parseClassOrNamedMixinApplication(
+        abstractToken, macroToken, classKeyword);
     indent--;
     return result;
   }
@@ -2494,19 +2496,30 @@
       Token begin,
       int referenceOffset,
       Token? newKeyword,
-      Token? prefix,
-      Token? period,
+      Token? firstToken,
+      Token? firstPeriod,
+      Token? secondToken,
+      Token? secondPeriod,
       Token identifierOrOperator) {
     doPrint('parseOneCommentReferenceRest('
         '$begin, '
         '$referenceOffset, '
         '$newKeyword, '
-        '$prefix, '
-        '$period, '
+        '$firstToken, '
+        '$firstPeriod, '
+        '$secondToken, '
+        '$secondPeriod, '
         '$identifierOrOperator)');
     indent++;
-    var result = super.parseOneCommentReferenceRest(begin, referenceOffset,
-        newKeyword, prefix, period, identifierOrOperator);
+    var result = super.parseOneCommentReferenceRest(
+        begin,
+        referenceOffset,
+        newKeyword,
+        firstToken,
+        firstPeriod,
+        secondToken,
+        secondPeriod,
+        identifierOrOperator);
     indent--;
     return result;
   }
diff --git a/pkg/front_end/test/parser_test_parser_creator.dart b/pkg/front_end/test/parser_test_parser_creator.dart
index 32cb010..37c6c0c 100644
--- a/pkg/front_end/test/parser_test_parser_creator.dart
+++ b/pkg/front_end/test/parser_test_parser_creator.dart
@@ -111,7 +111,8 @@
   ParserCreatorListener(this.out);
 
   @override
-  void beginClassDeclaration(Token begin, Token? abstractToken, Token name) {
+  void beginClassDeclaration(
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {
     if (name.lexeme == "Parser") insideParserClass = true;
   }
 
diff --git a/pkg/front_end/test/patching/data/abstract_class/libraries.json b/pkg/front_end/test/patching/data/abstract_class/libraries.json
new file mode 100644
index 0000000..a697508
--- /dev/null
+++ b/pkg/front_end/test/patching/data/abstract_class/libraries.json
@@ -0,0 +1,12 @@
+{
+  "none": {
+    "libraries": {
+      "test": {
+        "patches": [
+          "patch.dart"
+        ],
+        "uri": "origin.dart"
+      }
+    }
+  }
+}
diff --git a/pkg/front_end/test/patching/data/abstract_class/main.dart b/pkg/front_end/test/patching/data/abstract_class/main.dart
new file mode 100644
index 0000000..faf7854
--- /dev/null
+++ b/pkg/front_end/test/patching/data/abstract_class/main.dart
@@ -0,0 +1,14 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+/*cfe.library: nnbd=false*/
+
+/*cfe:nnbd.library: nnbd=true*/
+
+// ignore: uri_does_not_exist
+import 'dart:test';
+
+void test(Class cls) {}
+
+main() {}
diff --git a/pkg/front_end/test/patching/data/abstract_class/origin.dart b/pkg/front_end/test/patching/data/abstract_class/origin.dart
new file mode 100644
index 0000000..c8359e2
--- /dev/null
+++ b/pkg/front_end/test/patching/data/abstract_class/origin.dart
@@ -0,0 +1,31 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+/*cfe.library: nnbd=false*/
+
+/*cfe:nnbd.library: nnbd=true*/
+
+/*class: Interface:
+ isAbstract,
+ kernel-members=[
+  Interface.,
+  interfaceMethod],
+ scope=[interfaceMethod]
+*/
+/*member: Interface.:initializers=[SuperInitializer]*/
+abstract class Interface {
+  void interfaceMethod();
+}
+
+/*class: Class:
+ isAbstract,
+ kernel-members=[
+  Class.,
+  classMethod],
+ scope=[classMethod]
+*/
+/*member: Class.:initializers=[SuperInitializer]*/
+abstract class Class implements Interface {
+  external void classMethod();
+}
diff --git a/pkg/front_end/test/patching/data/abstract_class/patch.dart b/pkg/front_end/test/patching/data/abstract_class/patch.dart
new file mode 100644
index 0000000..9d11f24
--- /dev/null
+++ b/pkg/front_end/test/patching/data/abstract_class/patch.dart
@@ -0,0 +1,13 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// ignore: import_internal_library
+import 'dart:_internal';
+
+@patch
+class Class {
+  @patch
+  /*member: Class.classMethod:patch*/
+  void classMethod() {}
+}
diff --git a/pkg/front_end/test/patching/patching_test.dart b/pkg/front_end/test/patching/patching_test.dart
index 1cd2220..60129e5 100644
--- a/pkg/front_end/test/patching/patching_test.dart
+++ b/pkg/front_end/test/patching/patching_test.dart
@@ -118,6 +118,7 @@
   static const String error = 'message';
   static const String isNonNullableByDefault = 'nnbd';
   static const String patch = 'patch';
+  static const String isAbstract = 'isAbstract';
 }
 
 class PatchingDataExtractor extends CfeDataExtractor<Features> {
@@ -137,6 +138,9 @@
     ClassBuilder clsBuilder = lookupClassBuilder(compilerResult, cls)!;
 
     Features features = new Features();
+    if (cls.isAbstract) {
+      features.add(Tags.isAbstract);
+    }
     clsBuilder.scope.forEach((String name, Builder builder) {
       features.addElement(Tags.scope, name);
     });
diff --git a/pkg/front_end/test/spell_checking_list_code.txt b/pkg/front_end/test/spell_checking_list_code.txt
index 89cc303..81e6368 100644
--- a/pkg/front_end/test/spell_checking_list_code.txt
+++ b/pkg/front_end/test/spell_checking_list_code.txt
@@ -47,6 +47,7 @@
 anyone
 ap
 api
+apis
 app
 apparently
 applicable
@@ -73,6 +74,11 @@
 atom
 atoms
 attributes
+augment
+augmentation
+augmentations
+augmenting
+augments
 auto
 automagically
 auxiliary
@@ -140,6 +146,7 @@
 breadcrumbs
 brevity
 brianwilkerson
+bridge
 bs
 bsd
 bslash
@@ -225,15 +232,18 @@
 combinator
 combine2
 combiner
+communication
 compared
 compares
 compilations
+completers
 completes
 complicating
 component's
 comprehensive
 compressed
 compression
+comprise
 concat
 concatenate
 concerned
@@ -252,6 +262,7 @@
 containers
 continuations
 contra
+contribute
 convention
 coordinated
 coordinating
@@ -292,6 +303,7 @@
 dartbug
 dartdoc
 dartfix
+dartino
 dartlang
 dashes
 dc
@@ -309,6 +321,7 @@
 deeply
 def
 defaulting
+definitions
 degrades
 degree
 del
@@ -338,6 +351,7 @@
 dev
 device
 diff
+differs
 diffs
 digest
 digests
@@ -351,6 +365,7 @@
 disallow
 disambiguating
 disambiguator
+discovers
 disjoint
 dispatched
 distribute
@@ -418,6 +433,7 @@
 estimate
 eval
 execute
+executor
 exhausted
 existence
 existentially
@@ -530,6 +546,7 @@
 goto
 gotos
 gradually
+granted
 graphs
 growability
 gt
@@ -640,10 +657,14 @@
 interval
 intervals
 intl
+introspect
+introspection
+introspector
 ints
 invariants
 io
 is64
+isolate
 isolated
 issuecomment
 issuing
@@ -658,6 +679,7 @@
 java
 jenkins
 jensj
+job
 johnniwinther
 js
 json
@@ -669,6 +691,7 @@
 kallentu
 kernel's
 kernel2kernel
+kill
 klass
 kmillikin
 kotlin
@@ -704,6 +727,7 @@
 libs
 lifted
 lifter
+limiting
 linearized
 linebreak
 linter
@@ -945,6 +969,7 @@
 preexisting
 premark
 preorder
+prepares
 preprocess
 presented
 presubmit
@@ -963,10 +988,12 @@
 promo
 proof
 prop
+proposal
 propose
 proposed
 proto
 protobuf
+protocol
 ps
 pulled
 pure
@@ -1045,6 +1072,7 @@
 reexports
 ref
 reflect
+reflectee
 reflective
 reg
 regis
@@ -1060,6 +1088,8 @@
 relaxes
 released
 relink
+reload
+reloading
 remapped
 remedy
 removal
@@ -1076,11 +1106,14 @@
 repo
 repositories
 repurposed
+requests
 requirement
 res
 residue
 resource
 respond
+response
+responses
 restoring
 restriction
 resumed
@@ -1128,11 +1161,13 @@
 separators
 sequencing
 sequential
+serializable
 serializables
 serializer
 serializers
 serve
 server
+serves
 service
 session
 setable
@@ -1151,6 +1186,8 @@
 shr
 shrinking
 shru
+shut
+shutting
 si
 sibling
 siblings
@@ -1183,6 +1220,8 @@
 sourcemap
 spaced
 sparse
+spawn
+spawns
 spec
 spec'ed
 specialization
@@ -1243,6 +1282,7 @@
 substitutes
 substitutor
 suggests
+suite
 sum
 summarizing
 superclasses
@@ -1380,9 +1420,11 @@
 unifiable
 unification
 unifier
+unifies
 unify
 uninstantiable
 uninstantiated
+unintentionally
 unions
 uniqueness
 unittest
@@ -1451,6 +1493,7 @@
 w
 waiting
 wanting
+wants
 waste
 wasted
 watch
diff --git a/pkg/front_end/test/spell_checking_list_common.txt b/pkg/front_end/test/spell_checking_list_common.txt
index 28be9b1..39c9d6c 100644
--- a/pkg/front_end/test/spell_checking_list_common.txt
+++ b/pkg/front_end/test/spell_checking_list_common.txt
@@ -11,6 +11,7 @@
 
 a
 abbreviations
+abi
 ability
 able
 abort
diff --git a/pkg/front_end/test/spell_checking_list_messages.txt b/pkg/front_end/test/spell_checking_list_messages.txt
index ffc3264..30bf90d 100644
--- a/pkg/front_end/test/spell_checking_list_messages.txt
+++ b/pkg/front_end/test/spell_checking_list_messages.txt
@@ -10,6 +10,8 @@
 # automatic tools might move it to the top of the file.
 
 JS
+abispecificinteger
+abispecificintegermapping
 adjusting
 api
 argument(s)
@@ -65,6 +67,7 @@
 pubspec.yaml
 re
 sdksummary
+size
 solutions
 stacktrace
 staticinterop
diff --git a/pkg/front_end/test/spell_checking_list_tests.txt b/pkg/front_end/test/spell_checking_list_tests.txt
index 2a6a8f4..ea9623a 100644
--- a/pkg/front_end/test/spell_checking_list_tests.txt
+++ b/pkg/front_end/test/spell_checking_list_tests.txt
@@ -675,6 +675,8 @@
 misspelled
 mistake
 mistakes
+mixin1
+mixin2
 mmethod
 mod
 modelled
@@ -903,6 +905,7 @@
 std
 stress
 string2
+stringy
 strip
 strongest
 stub's
diff --git a/pkg/front_end/test/unit_test_suites.dart b/pkg/front_end/test/unit_test_suites.dart
index ef12180..c9acb09 100644
--- a/pkg/front_end/test/unit_test_suites.dart
+++ b/pkg/front_end/test/unit_test_suites.dart
@@ -20,6 +20,7 @@
 import 'fasta/incremental_dartino_suite.dart' as incremental_dartino
     show createContext;
 import 'fasta/messages_suite.dart' as messages show createContext;
+import 'fasta/modular_suite.dart' as modular show createContext;
 import 'fasta/outline_suite.dart' as outline show createContext;
 import 'fasta/strong_suite.dart' as strong show createContext;
 import 'fasta/text_serialization_suite.dart' as text_serialization
@@ -453,6 +454,13 @@
     requiresGit: true,
   ),
   const Suite(
+    "fasta/modular",
+    modular.createContext,
+    "../../testing.json",
+    path: "fasta/modular_suite.dart",
+    shardCount: 4,
+  ),
+  const Suite(
     "fasta/weak",
     weak.createContext,
     "../../testing.json",
diff --git a/pkg/front_end/testcases/agnostic/as.dart.weak.modular.expect b/pkg/front_end/testcases/agnostic/as.dart.weak.modular.expect
new file mode 100644
index 0000000..40e7073
--- /dev/null
+++ b/pkg/front_end/testcases/agnostic/as.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static const field core::List<core::int> a = #C1;
+static const field core::List<core::int> b = #C2;
+static method main() → void {}
+
+constants  {
+  #C1 = <Null>[]
+  #C2 = <core::int?>[]
+}
diff --git a/pkg/front_end/testcases/agnostic/identical.dart.weak.modular.expect b/pkg/front_end/testcases/agnostic/identical.dart.weak.modular.expect
new file mode 100644
index 0000000..f5a7aaa
--- /dev/null
+++ b/pkg/front_end/testcases/agnostic/identical.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static const field core::List<core::int> a = #C1;
+static const field core::List<core::int?> b = #C2;
+static const field core::bool c = #C3;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = <core::int*>[]
+  #C2 = <core::int?>[]
+  #C3 = false
+}
diff --git a/pkg/front_end/testcases/agnostic/is.dart.weak.modular.expect b/pkg/front_end/testcases/agnostic/is.dart.weak.modular.expect
new file mode 100644
index 0000000..b52395a
--- /dev/null
+++ b/pkg/front_end/testcases/agnostic/is.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static const field core::bool a = #C1;
+static const field core::bool b = #C1;
+static method main() → void {}
+
+constants  {
+  #C1 = true
+}
diff --git a/pkg/front_end/testcases/agnostic/map.dart.weak.modular.expect b/pkg/front_end/testcases/agnostic/map.dart.weak.modular.expect
new file mode 100644
index 0000000..70e1f24
--- /dev/null
+++ b/pkg/front_end/testcases/agnostic/map.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static const field core::List<core::int> a = #C1;
+static const field core::List<core::int?> b = #C2;
+static const field core::Map<core::List<core::int?>, core::int> c = #C5;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = <core::int*>[]
+  #C2 = <core::int?>[]
+  #C3 = 0
+  #C4 = 1
+  #C5 = <core::List<core::int?>*, core::int*>{#C1:#C3, #C2:#C4)
+}
diff --git a/pkg/front_end/testcases/agnostic/set.dart.weak.modular.expect b/pkg/front_end/testcases/agnostic/set.dart.weak.modular.expect
new file mode 100644
index 0000000..add03f5
--- /dev/null
+++ b/pkg/front_end/testcases/agnostic/set.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static const field core::List<core::int> a = #C1;
+static const field core::List<core::int?> b = #C2;
+static const field core::Set<core::List<core::int?>> c = #C3;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = <core::int*>[]
+  #C2 = <core::int?>[]
+  #C3 = <core::List<core::int?>*>{#C1, #C2}
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_assert_statements.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_assert_statements.dart.weak.modular.expect
new file mode 100644
index 0000000..89d51078
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_assert_statements.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::int var1 = #C1;
+static const field core::int var2 = #C1;
+static method fn() → core::int {
+  core::int x = 0;
+  assert(x =={core::num::==}{(core::Object) → core::bool} 0, "fail");
+  return x;
+}
+static method fn2() → core::int {
+  core::int x = 0;
+  assert((() → core::bool {
+    core::int y = x.{core::num::+}(1){(core::num) → core::int};
+    return y =={core::num::==}{(core::Object) → core::bool} 1;
+  })(){() → core::bool});
+  return x;
+}
+static method main() → void {
+  exp::Expect::equals(#C1, 0);
+  exp::Expect::equals(#C1, 0);
+}
+
+constants  {
+  #C1 = 0
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_block.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_block.dart.weak.modular.expect
new file mode 100644
index 0000000..ee6a074
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_block.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static method blockTest() → void {
+  function x() → core::int
+    return 1;
+  exp::Expect::equals(#C1, 1);
+  {
+    function x() → core::int
+      return 2;
+    exp::Expect::equals(#C2, 2);
+    {
+      function x() → core::int
+        return 3;
+      exp::Expect::equals(#C3, 3);
+    }
+  }
+  exp::Expect::equals(#C1, 1);
+}
+static method blockTest1() → void {
+  function x() → core::int {
+    core::int z = 3;
+    {
+      core::int z = 4;
+    }
+    return z;
+  }
+  exp::Expect::equals(#C3, 3);
+}
+static method main() → void {
+  self::blockTest();
+  self::blockTest1();
+}
+
+constants  {
+  #C1 = 1
+  #C2 = 2
+  #C3 = 3
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_closures.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_closures.dart.weak.modular.expect
new file mode 100644
index 0000000..a1bc565
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_closures.dart.weak.modular.expect
@@ -0,0 +1,86 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::int var1 = #C1;
+static const field core::int var2 = #C1;
+static const field core::int y = #C2;
+static const field core::int var3 = #C3;
+static const field core::int var4 = #C1;
+static const field core::int var5 = #C4;
+static const field core::int var6 = #C4;
+static method foo() → core::int {
+  () → () → core::int f = () → () → core::int {
+    core::int count = 0;
+    function baz() → core::int {
+      count = count.{core::num::+}(1){(core::num) → core::int};
+      return count;
+    }
+    return baz;
+  };
+  () → core::int c1 = f(){() → () → core::int};
+  () → core::int c2 = f(){() → () → core::int};
+  core::int c1_val1 = c1(){() → core::int};
+  assert(c1_val1 =={core::num::==}{(core::Object) → core::bool} 1);
+  core::int c1_val2 = c1(){() → core::int};
+  assert(c1_val2 =={core::num::==}{(core::Object) → core::bool} 2);
+  core::int c1_val3 = c1(){() → core::int};
+  assert(c1_val3 =={core::num::==}{(core::Object) → core::bool} 3);
+  core::int c2_val1 = c2(){() → core::int};
+  assert(c1_val1 =={core::num::==}{(core::Object) → core::bool} 1);
+  core::int c2_val2 = c2(){() → core::int};
+  assert(c1_val2 =={core::num::==}{(core::Object) → core::bool} 2);
+  core::int c2_val3 = c2(){() → core::int};
+  assert(c1_val3 =={core::num::==}{(core::Object) → core::bool} 3);
+  return 0;
+}
+static method fn() → core::int {
+  return (() → core::int => 0)(){() → core::int};
+}
+static method fn3() → core::int {
+  core::int y = 2;
+  return y;
+}
+static method fn4() → core::int {
+  core::int x = 0;
+  function innerFn() → core::int {
+    return x;
+  }
+  return innerFn(){() → core::int};
+}
+static method fn5(core::int a) → core::int {
+  function recurse(core::int b) → core::int {
+    if(b =={core::num::==}{(core::Object) → core::bool} 1)
+      return 1;
+    core::int result = recurse(b.{core::num::-}(1){(core::num) → core::int}){(core::int) → core::int};
+    return b.{core::num::*}(result){(core::num) → core::int};
+  }
+  return recurse(a){(core::int) → core::int};
+}
+static method fn6(core::int a) → core::int {
+  function recurse() → core::int {
+    a = a.{core::num::-}(1){(core::num) → core::int};
+    if(a =={core::num::==}{(core::Object) → core::bool} 1)
+      return 1;
+    return a.{core::num::*}(recurse(){() → core::int}){(core::num) → core::int};
+  }
+  return recurse(){() → core::int};
+}
+static method main() → void {
+  exp::Expect::equals(#C1, 0);
+  exp::Expect::equals(#C1, 0);
+  exp::Expect::equals(#C3, 2);
+  exp::Expect::equals(#C1, 0);
+  exp::Expect::equals(#C4, 6);
+  exp::Expect::equals(#C4, 6);
+}
+
+constants  {
+  #C1 = 0
+  #C2 = 1
+  #C3 = 2
+  #C4 = 6
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_const_ctor.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_const_ctor.dart.weak.modular.expect
new file mode 100644
index 0000000..819097c
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_const_ctor.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+class Simple extends core::Object /*hasConstConstructor*/  {
+  final field core::String name;
+  const constructor •(core::String name) → self::Simple
+    : self::Simple::name = name, super core::Object::•() {
+    assert(this.{self::Simple::name}{core::String} =={core::String::==}{(core::Object) → core::bool} #C1);
+  }
+}
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A
+    : super core::Object::•() {
+    return;
+  }
+}
+static const field core::String printString = #C1;
+static const field self::Simple var1 = #C2;
+static const field self::A var2 = #C3;
+static const field self::A var3 = #C3;
+static method fn() → self::A
+  return new self::A::•();
+static method main() → void {
+  exp::Expect::equals(#C2.{self::Simple::name}{core::String}, #C1);
+}
+
+constants  {
+  #C1 = "print"
+  #C2 = self::Simple {name:#C1}
+  #C3 = self::A {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///const_functions_const_ctor.dart:
+- Simple. (from org-dartlang-testcase:///const_functions_const_ctor.dart:14:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- A. (from org-dartlang-testcase:///const_functions_const_ctor.dart:21:9)
diff --git a/pkg/front_end/testcases/const_functions/const_functions_const_ctor_error.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_const_ctor_error.dart.weak.modular.expect
new file mode 100644
index 0000000..b972e0f
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_const_ctor_error.dart.weak.modular.expect
@@ -0,0 +1,98 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/const_functions/const_functions_const_ctor_error.dart:41:14: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+// Try using a constructor or factory that is 'const'.
+// const var4 = C();
+//              ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_const_ctor_error.dart:26:5: Error: Constructors can't have a return type.
+// Try removing the return type.
+//     return Simple2(this.name);
+//     ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_const_ctor_error.dart:12:14: Error: Constant evaluation error:
+// const var1 = Simple(printString);
+//              ^
+// pkg/front_end/testcases/const_functions/const_functions_const_ctor_error.dart:17:22: Context: This assertion failed.
+//     assert(this.name != printString);
+//                      ^
+// pkg/front_end/testcases/const_functions/const_functions_const_ctor_error.dart:12:7: Context: While analyzing:
+// const var1 = Simple(printString);
+//       ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_const_ctor_error.dart:30:14: Error: Constant evaluation error:
+// const var3 = B();
+//              ^
+// pkg/front_end/testcases/const_functions/const_functions_const_ctor_error.dart:33:14: Context: This assertion failed.
+//     assert(1 == 2);
+//              ^
+// pkg/front_end/testcases/const_functions/const_functions_const_ctor_error.dart:30:7: Context: While analyzing:
+// const var3 = B();
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "package:expect/expect.dart";
+
+class Simple extends core::Object /*hasConstConstructor*/  {
+  final field core::String name;
+  const constructor •(core::String name) → self::Simple
+    : self::Simple::name = name, super core::Object::•() {
+    assert(!(this.{self::Simple::name}{core::String} =={core::String::==}{(core::Object) → core::bool} #C1));
+  }
+}
+class Simple2 extends core::Object /*hasConstConstructor*/  {
+  final field core::String name;
+  const constructor •(core::String name) → self::Simple2
+    : self::Simple2::name = name, super core::Object::•() {
+    invalid-expression "pkg/front_end/testcases/const_functions/const_functions_const_ctor_error.dart:26:5: Error: Constructors can't have a return type.
+Try removing the return type.
+    return Simple2(this.name);
+    ^";
+  }
+}
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A
+    : super core::Object::•() {
+    assert(1 =={core::num::==}{(core::Object) → core::bool} 2);
+  }
+}
+class B extends self::A /*hasConstConstructor*/  {
+  const constructor •() → self::B
+    : super self::A::•()
+    ;
+}
+class C extends core::Object {
+  field core::int? x = null;
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+static const field core::String printString = #C1;
+static const field self::Simple var1 = invalid-expression "This assertion failed.";
+static const field self::Simple2 var2 = invalid-expression "pkg/front_end/testcases/const_functions/const_functions_const_ctor_error.dart:26:5: Error: Constructors can't have a return type.
+Try removing the return type.
+    return Simple2(this.name);
+    ^";
+static const field self::B var3 = invalid-expression "This assertion failed.";
+static const field invalid-type var4 = invalid-expression "pkg/front_end/testcases/const_functions/const_functions_const_ctor_error.dart:41:14: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+Try using a constructor or factory that is 'const'.
+const var4 = C();
+             ^";
+static method main() → void {}
+
+constants  {
+  #C1 = "print"
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///const_functions_const_ctor_error.dart:
+- Simple. (from org-dartlang-testcase:///const_functions_const_ctor_error.dart:16:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Simple2. (from org-dartlang-testcase:///const_functions_const_ctor_error.dart:25:9)
+- B. (from org-dartlang-testcase:///const_functions_const_ctor_error.dart:38:9)
+- A. (from org-dartlang-testcase:///const_functions_const_ctor_error.dart:32:9)
diff --git a/pkg/front_end/testcases/const_functions/const_functions_const_factory.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_const_factory.dart.weak.modular.expect
new file mode 100644
index 0000000..b9d7932
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_const_factory.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+class MessageType extends core::Object /*hasConstConstructor*/  {
+  static const field self::MessageType print = #C2;
+  static const field self::MessageType skip = #C4;
+  final field core::String name;
+  const constructor _(core::String name) → self::MessageType
+    : self::MessageType::name = name, super core::Object::•()
+    ;
+  static factory parse(core::String name) → self::MessageType {
+    if(name =={core::String::==}{(core::Object) → core::bool} "print") {
+      return #C2;
+    }
+    return #C4;
+  }
+}
+static const field self::MessageType printConst = #C2;
+static method main() → void {
+  exp::Expect::equals(#C2, #C2);
+}
+
+constants  {
+  #C1 = "print"
+  #C2 = self::MessageType {name:#C1}
+  #C3 = "skip"
+  #C4 = self::MessageType {name:#C3}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///const_functions_const_factory.dart:
+- MessageType._ (from org-dartlang-testcase:///const_functions_const_factory.dart:25:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/const_functions/const_functions_do_statements.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_do_statements.dart.weak.modular.expect
new file mode 100644
index 0000000..4442626
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_do_statements.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::int var1 = #C1;
+static const field core::int var2 = #C2;
+static const field core::int var3 = #C3;
+static const field core::int var4 = #C4;
+static method fn() → core::int {
+  core::int x = 0;
+  do {
+    x = x.{core::num::+}(1){(core::num) → core::int};
+  }
+  while (x.{core::num::<}(2){(core::num) → core::bool})
+  return x;
+}
+static method fn2(core::int a) → core::int {
+  core::int x = 0;
+  core::int b = 0;
+  #L1:
+  do {
+    if(x.{core::num::>}(5){(core::num) → core::bool})
+      break #L1;
+    x = x.{core::num::+}(a){(core::num) → core::int};
+    b = b.{core::num::+}(1){(core::num) → core::int};
+  }
+  while (b.{core::num::<}(2){(core::num) → core::bool})
+  return x;
+}
+static method fn3() → core::int {
+  core::int x = 0;
+  core::int b = 0;
+  do
+    #L2:
+    {
+      x = x.{core::num::+}(1){(core::num) → core::int};
+      if(x.{core::num::%}(2){(core::num) → core::int} =={core::num::==}{(core::Object) → core::bool} 1)
+        break #L2;
+      b = b.{core::num::+}(x){(core::num) → core::int};
+    }
+  while (x.{core::num::<}(5){(core::num) → core::bool})
+  return b;
+}
+static method main() → void {
+  exp::Expect::equals(#C1, 2);
+  exp::Expect::equals(#C2, 4);
+  exp::Expect::equals(#C3, 10);
+  exp::Expect::equals(#C4, 6);
+}
+
+constants  {
+  #C1 = 2
+  #C2 = 4
+  #C3 = 10
+  #C4 = 6
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_for_statements.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_for_statements.dart.weak.modular.expect
new file mode 100644
index 0000000..f4906f3
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_for_statements.dart.weak.modular.expect
@@ -0,0 +1,102 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::int var1 = #C1;
+static const field core::int var2 = #C2;
+static const field core::int var3 = #C3;
+static const field core::int var4 = #C4;
+static const field core::int var5 = #C5;
+static const field core::int var6 = #C1;
+static const field core::int var7 = #C6;
+static const field core::int var8 = #C2;
+static const field core::int var9 = #C7;
+static const field core::int var10 = #C8;
+static method fn(core::int a) → core::int {
+  core::int b = a;
+  for (core::int i = 0; i.{core::num::<}(2){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+    b = b.{core::num::+}(a){(core::num) → core::int};
+  }
+  return b;
+}
+static method fn1(core::int a) → core::int {
+  core::int b = a;
+  for (core::int i = 0; ; i = i.{core::num::+}(1){(core::num) → core::int}) {
+    b = b.{core::num::*}(3){(core::num) → core::int};
+    if(b.{core::num::>}(10){(core::num) → core::bool})
+      return b;
+  }
+}
+static method fn2() → core::int {
+  for (core::int i = 0, core::int j = 2; ; i = i.{core::num::+}(2){(core::num) → core::int}, j = j.{core::num::+}(1){(core::num) → core::int}) {
+    if(i.{core::num::+}(j){(core::num) → core::int}.{core::num::>}(10){(core::num) → core::bool}) {
+      return i.{core::num::+}(j){(core::num) → core::int};
+    }
+  }
+}
+static method fnContinue() → core::int {
+  core::int a = 0;
+  for (core::int i = 0; i.{core::num::<}(5){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int})
+    #L1:
+    {
+      if(i.{core::num::%}(2){(core::num) → core::int} =={core::num::==}{(core::Object) → core::bool} 1)
+        break #L1;
+      a = a.{core::num::+}(i){(core::num) → core::int};
+    }
+  return a;
+}
+static method fnBreak(core::int a) → core::int {
+  core::int b = a;
+  #L2:
+  for (core::int i = 0; i.{core::num::<}(2){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+    if(b =={core::num::==}{(core::Object) → core::bool} 2)
+      break #L2;
+    b = b.{core::num::+}(a){(core::num) → core::int};
+  }
+  return b;
+}
+static method fnNestedFor() → core::int {
+  core::int a = 0;
+  for (; ; ) {
+    #L3:
+    for (; ; ) {
+      break #L3;
+    }
+    return 1;
+  }
+}
+static method fnBreakLabel() → core::int {
+  #L4:
+  for (; ; ) {
+    for (; ; ) {
+      break #L4;
+    }
+  }
+  return 3;
+}
+static method main() → void {
+  exp::Expect::equals(#C1, 6);
+  exp::Expect::equals(#C2, 9);
+  exp::Expect::equals(#C3, 18);
+  exp::Expect::equals(#C4, 27);
+  exp::Expect::equals(#C5, 11);
+  exp::Expect::equals(#C1, 6);
+  exp::Expect::equals(#C6, 2);
+  exp::Expect::equals(#C2, 9);
+  exp::Expect::equals(#C7, 1);
+  exp::Expect::equals(#C8, 3);
+}
+
+constants  {
+  #C1 = 6
+  #C2 = 9
+  #C3 = 18
+  #C4 = 27
+  #C5 = 11
+  #C6 = 2
+  #C7 = 1
+  #C8 = 3
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_if_statements.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_if_statements.dart.weak.modular.expect
new file mode 100644
index 0000000..525bcb7
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_if_statements.dart.weak.modular.expect
@@ -0,0 +1,86 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::int var1 = #C1;
+static const field core::int var2 = #C2;
+static const field core::int var3 = #C3;
+static const field core::int one = #C4;
+static const field core::int var4 = #C1;
+static const field core::int var5 = #C2;
+static const field core::int var6 = #C1;
+static const field core::int var6_1 = #C2;
+static const field core::int var6_2 = #C3;
+static const field core::int var7 = #C5;
+static const field core::int var8 = #C6;
+static method ifTest(core::int a) → core::int {
+  if(a =={core::num::==}{(core::Object) → core::bool} 1) {
+    return 100;
+  }
+  else
+    if(a =={core::num::==}{(core::Object) → core::bool} 2) {
+      return 200;
+    }
+    else {
+      return 300;
+    }
+}
+static method ifTest2(core::int a) → core::int {
+  if(a =={core::num::==}{(core::Object) → core::bool} #C4) {
+    return 100;
+  }
+  else {
+    return 200;
+  }
+}
+static method ifTest3(core::int a) → core::int {
+  if(a.{core::num::>}(0){(core::num) → core::bool}) {
+    if(a =={core::num::==}{(core::Object) → core::bool} 1)
+      return 100;
+    return 200;
+  }
+  return 300;
+}
+static method ifTest4(core::int a) → core::int {
+  core::int b = a;
+  if(a =={core::num::==}{(core::Object) → core::bool} 1) {
+    b = b.{core::num::+}(a){(core::num) → core::int};
+    if(a.{core::num::%}(2){(core::num) → core::int} =={core::num::==}{(core::Object) → core::bool} 1) {
+      b = b.{core::num::+}(a){(core::num) → core::int};
+    }
+  }
+  else
+    if(a =={core::num::==}{(core::Object) → core::bool} 2) {
+      b = b.{core::num::-}(a){(core::num) → core::int};
+    }
+  return b;
+}
+static method ifTest5() → core::int {
+  core::int x = 10;
+  if(true) {
+    core::int x = 20;
+  }
+  return x;
+}
+static method main() → void {
+  exp::Expect::equals(#C1, 100);
+  exp::Expect::equals(#C2, 200);
+  exp::Expect::equals(#C3, 300);
+  exp::Expect::equals(#C1, 100);
+  exp::Expect::equals(#C2, 200);
+  exp::Expect::equals(#C1, 100);
+  exp::Expect::equals(#C5, 3);
+  exp::Expect::equals(#C6, 10);
+}
+
+constants  {
+  #C1 = 100
+  #C2 = 200
+  #C3 = 300
+  #C4 = 1
+  #C5 = 3
+  #C6 = 10
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_instance_fields.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_instance_fields.dart.weak.modular.expect
new file mode 100644
index 0000000..889f2d5
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_instance_fields.dart.weak.modular.expect
@@ -0,0 +1,65 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+class A extends core::Object /*hasConstConstructor*/  {
+  final field core::int y;
+  const constructor •(core::int y) → self::A
+    : self::A::y = y, super core::Object::•()
+    ;
+}
+class B extends self::A /*hasConstConstructor*/  {
+  const constructor •(core::int x) → self::B
+    : super self::A::•(x)
+    ;
+}
+class C extends self::A /*hasConstConstructor*/  {
+  @#C1
+  final field core::int y = 2;
+  const constructor •() → self::C
+    : super self::A::•(100)
+    ;
+}
+static const field core::int var1 = #C2;
+static const field core::int var2 = #C2;
+static const field core::int var3 = #C2;
+static const field core::int var4 = #C2;
+static const field core::int var5 = #C3;
+static method fn() → core::int
+  return #C4.{self::A::y}{core::int};
+static method fn2() → core::int {
+  self::A x = #C4;
+  return x.{self::A::y}{core::int};
+}
+static method fn4() → core::int
+  return #C5.{self::A::y}{core::int};
+static method fn5() → core::int
+  return #C7.{self::C::y}{core::int};
+static method main() → void {
+  exp::Expect::equals(#C2, 1);
+  exp::Expect::equals(#C2, 1);
+  exp::Expect::equals(#C2, 1);
+  exp::Expect::equals(#C2, 1);
+  exp::Expect::equals(#C3, 2);
+}
+
+constants  {
+  #C1 = core::_Override {}
+  #C2 = 1
+  #C3 = 2
+  #C4 = self::A {y:#C2}
+  #C5 = self::B {y:#C2}
+  #C6 = 100
+  #C7 = self::C {y:#C3, y:#C6}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///const_functions_instance_fields.dart:
+- A. (from org-dartlang-testcase:///const_functions_instance_fields.dart:12:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- B. (from org-dartlang-testcase:///const_functions_instance_fields.dart:27:9)
+- C. (from org-dartlang-testcase:///const_functions_instance_fields.dart:37:9)
diff --git a/pkg/front_end/testcases/const_functions/const_functions_instance_methods.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_instance_methods.dart.weak.modular.expect
new file mode 100644
index 0000000..d74febc
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_instance_methods.dart.weak.modular.expect
@@ -0,0 +1,138 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class B extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::B
+    : super core::Object::•()
+    ;
+  @#C1
+  method toString() → core::String
+    return "B";
+}
+class C extends core::Object /*hasConstConstructor*/  {
+  final field core::int y;
+  const constructor •(core::int y) → self::C
+    : self::C::y = y, super core::Object::•()
+    ;
+  method fn() → core::int {
+    if(this.{self::C::y}{core::int} =={core::num::==}{(core::Object) → core::bool} 1)
+      return 100;
+    return 200;
+  }
+}
+class D extends self::C /*hasConstConstructor*/  {
+  const constructor •(core::int y) → self::D
+    : super self::C::•(y)
+    ;
+  @#C1
+  method fn() → core::int
+    return 300;
+}
+class E extends self::C /*hasConstConstructor*/  {
+  const constructor •(core::int y) → self::E
+    : super self::C::•(y)
+    ;
+}
+class F<T extends core::Object? = dynamic, U extends core::Object? = dynamic, V extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::F<self::F::T%, self::F::U%, self::F::V%>
+    : super core::Object::•()
+    ;
+  method fn(covariant-by-class self::F::U% x) → self::F::U%
+    return x;
+}
+class G<T extends core::Object? = dynamic> extends self::F<self::G::T%, core::String, core::num> /*hasConstConstructor*/  {
+  const constructor •() → self::G<self::G::T%>
+    : super self::F::•()
+    ;
+}
+static const field core::String var1 = #C2;
+static const field core::String toString1 = #C2;
+static const field core::String var2 = #C3;
+static const field core::String toString2 = #C3;
+static const field core::int var3 = #C4;
+static const field core::int var4 = #C5;
+static const field core::int fnVal1 = #C4;
+static const field core::int fnVal2 = #C5;
+static const field core::int var5 = #C6;
+static const field core::int fnVal3 = #C6;
+static const field core::int var6 = #C5;
+static const field core::int fnVal4 = #C4;
+static const field core::String var7 = #C7;
+static const field core::String fnVal5 = #C7;
+static const field core::String var8 = #C7;
+static const field core::String fnVal6 = #C7;
+static method fn() → core::String
+  return #C8.{core::Object::toString}(){() → core::String};
+static method fn2() → core::String
+  return #C9.{self::B::toString}(){() → core::String};
+static method fn3() → core::int
+  return #C11.{self::C::fn}(){() → core::int};
+static method fn4() → core::int
+  return #C13.{self::C::fn}(){() → core::int};
+static method fn5() → core::int
+  return #C14.{self::D::fn}(){() → core::int};
+static method fn6() → core::int
+  return #C15.{self::C::fn}(){() → core::int};
+static method fn7() → core::String
+  return #C16.{self::F::fn}("string"){(core::String) → core::String};
+static method fn8() → core::String
+  return #C17.{self::F::fn}("string"){(core::String) → core::String};
+static method main() → void {
+  exp::Expect::equals(#C2, #C8.{core::Object::toString}(){() → core::String});
+  exp::Expect::equals(#C2, #C8.{core::Object::toString}(){() → core::String});
+  exp::Expect::equals(#C3, #C9.{self::B::toString}(){() → core::String});
+  exp::Expect::equals(#C3, #C9.{self::B::toString}(){() → core::String});
+  exp::Expect::equals(#C4, 200);
+  exp::Expect::equals(#C5, 100);
+  exp::Expect::equals(#C4, 200);
+  exp::Expect::equals(#C5, 100);
+  exp::Expect::equals(#C6, 300);
+  exp::Expect::equals(#C6, 300);
+  exp::Expect::equals(#C5, 100);
+  exp::Expect::equals(#C4, 200);
+  exp::Expect::equals(#C7, "string");
+  exp::Expect::equals(#C7, "string");
+  exp::Expect::equals(#C7, "string");
+  exp::Expect::equals(#C7, "string");
+}
+
+constants  {
+  #C1 = core::_Override {}
+  #C2 = "Instance of 'A'"
+  #C3 = "B"
+  #C4 = 200
+  #C5 = 100
+  #C6 = 300
+  #C7 = "string"
+  #C8 = self::A {}
+  #C9 = self::B {}
+  #C10 = 0
+  #C11 = self::C {y:#C10}
+  #C12 = 1
+  #C13 = self::C {y:#C12}
+  #C14 = self::D {y:#C12}
+  #C15 = self::E {y:#C12}
+  #C16 = self::F<core::int*, core::String*, core::num*> {}
+  #C17 = self::G<core::int*> {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///const_functions_instance_methods.dart:
+- A. (from org-dartlang-testcase:///const_functions_instance_methods.dart:10:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- B. (from org-dartlang-testcase:///const_functions_instance_methods.dart:14:9)
+- C. (from org-dartlang-testcase:///const_functions_instance_methods.dart:23:9)
+- D. (from org-dartlang-testcase:///const_functions_instance_methods.dart:32:9)
+- E. (from org-dartlang-testcase:///const_functions_instance_methods.dart:39:9)
+- F. (from org-dartlang-testcase:///const_functions_instance_methods.dart:43:9)
+- G. (from org-dartlang-testcase:///const_functions_instance_methods.dart:48:9)
diff --git a/pkg/front_end/testcases/const_functions/const_functions_list.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_list.dart.weak.modular.expect
new file mode 100644
index 0000000..bc35178
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_list.dart.weak.modular.expect
@@ -0,0 +1,125 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::int firstVar = #C1;
+static const field core::int firstCatchVar = #C2;
+static const field core::bool isEmptyVar = #C3;
+static const field core::bool isNotEmptyVar = #C4;
+static const field core::int lastVar = #C5;
+static const field core::int lastCatchVar = #C2;
+static const field core::int lengthVar = #C5;
+static const field core::int singleVar = #C1;
+static const field core::int singleCatchVar = #C2;
+static const field core::int singleCatchVar2 = #C2;
+static const field core::int getWithIndexVar = #C1;
+static const field core::int rangeErrorCatchVar = #C2;
+static const field core::List<core::int> mutableListVar = #C6;
+static const field core::List<core::int> mutableListAddVar = #C8;
+static method firstFn() → core::int {
+  return #C6.{core::Iterable::first}{core::int};
+}
+static method firstCatchFn() → core::int {
+  try {
+    core::int v = #C9.{core::Iterable::first}{core::int};
+  }
+  on core::StateError catch(no-exception-var) {
+    return 0;
+  }
+  return 1;
+}
+static method isEmptyFn() → core::bool {
+  return #C6.{core::Iterable::isEmpty}{core::bool};
+}
+static method isNotEmptyFn() → core::bool {
+  return #C6.{core::Iterable::isNotEmpty}{core::bool};
+}
+static method lastFn() → core::int {
+  return #C6.{core::Iterable::last}{core::int};
+}
+static method lastCatchFn() → core::int {
+  try {
+    core::int v = #C9.{core::Iterable::last}{core::int};
+  }
+  on core::StateError catch(no-exception-var) {
+    return 0;
+  }
+  return 1;
+}
+static method lengthFn() → core::int {
+  return #C6.{core::List::length}{core::int};
+}
+static method singleFn() → core::int {
+  return #C10.{core::Iterable::single}{core::int};
+}
+static method singleCatchFn() → core::int {
+  try {
+    core::int v = #C9.{core::Iterable::single}{core::int};
+  }
+  on core::StateError catch(no-exception-var) {
+    return 0;
+  }
+  return 1;
+}
+static method singleCatchFn2() → core::int {
+  try {
+    core::int v = #C6.{core::Iterable::single}{core::int};
+  }
+  on core::StateError catch(no-exception-var) {
+    return 0;
+  }
+  return 1;
+}
+static method getWithIndexFn() → core::int {
+  return #C10.{core::List::[]}(0){(core::int) → core::int};
+}
+static method rangeErrorCatchFn() → core::int {
+  try {
+    core::int v = #C10.{core::List::[]}(1){(core::int) → core::int};
+  }
+  on core::RangeError catch(no-exception-var) {
+    return 0;
+  }
+  return 1;
+}
+static method mutableList() → core::List<core::int> {
+  core::List<core::int> x = <core::int>[1, 2];
+  return x;
+}
+static method mutableListAdd() → core::List<core::int> {
+  core::List<core::int> x = <core::int>[1, 2];
+  x.{core::List::add}(3){(core::int) → void};
+  return x;
+}
+static method main() → void {
+  exp::Expect::equals(#C1, 1);
+  exp::Expect::equals(#C2, 0);
+  exp::Expect::equals(#C3, false);
+  exp::Expect::equals(#C4, true);
+  exp::Expect::equals(#C5, 2);
+  exp::Expect::equals(#C2, 0);
+  exp::Expect::equals(#C5, 2);
+  exp::Expect::equals(#C1, 1);
+  exp::Expect::equals(#C2, 0);
+  exp::Expect::equals(#C2, 0);
+  exp::Expect::equals(#C1, 1);
+  exp::Expect::equals(#C2, 0);
+  exp::Expect::equals(#C6, #C6);
+  exp::Expect::equals(#C8, #C8);
+}
+
+constants  {
+  #C1 = 1
+  #C2 = 0
+  #C3 = false
+  #C4 = true
+  #C5 = 2
+  #C6 = <core::int*>[#C1, #C5]
+  #C7 = 3
+  #C8 = <core::int*>[#C1, #C5, #C7]
+  #C9 = <core::int*>[]
+  #C10 = <core::int*>[#C1]
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_list_error.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_list_error.dart.weak.modular.expect
new file mode 100644
index 0000000..a7c5460
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_list_error.dart.weak.modular.expect
@@ -0,0 +1,126 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:36:12: Error: The getter 'invalidProperty' isn't defined for the class 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'invalidProperty'.
+//   return x.invalidProperty;
+//            ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:54:12: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//   return x[0.1];
+//            ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:9:24: Error: Constant evaluation error:
+// const firstException = firstExceptionFn();
+//                        ^
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:12:12: Context: Unhandled core exception: Bad state: No element
+//   return x.first;
+//            ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:15:23: Error: Constant evaluation error:
+// const lastException = lastExceptionFn();
+//                       ^
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:18:12: Context: Unhandled core exception: Bad state: No element
+//   return x.last;
+//            ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:21:25: Error: Constant evaluation error:
+// const singleException = singleExceptionFn();
+//                         ^
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:24:12: Context: Unhandled core exception: Bad state: No element
+//   return x.single;
+//            ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:27:30: Error: Constant evaluation error:
+// const singleExceptionMulti = singleExceptionMultiFn();
+//                              ^
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:30:12: Context: Unhandled core exception: Bad state: Too many elements
+//   return x.single;
+//            ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:39:31: Error: Constant evaluation error:
+// const getWithIndexException = getWithIndexExceptionFn();
+//                               ^
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:42:11: Context: Unhandled core exception: RangeError: Index out of range: index should be less than 1: 1
+//   return x[1];
+//           ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:45:32: Error: Constant evaluation error:
+// const getWithIndexException2 = getWithIndexExceptionFn2();
+//                                ^
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:48:11: Context: Unhandled core exception: RangeError: Index out of range: index must not be negative: -1
+//   return x[-1];
+//           ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:57:31: Error: Constant evaluation error:
+// const constListAddException = constListAddExceptionFn();
+//                               ^
+// pkg/front_end/testcases/const_functions/const_functions_list_error.dart:60:5: Context: Unhandled core exception: Unsupported operation: add
+//   x.add(3);
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "package:expect/expect.dart";
+
+static const field core::int firstException = invalid-expression "Unhandled core exception: Bad state: No element";
+static const field core::int lastException = invalid-expression "Unhandled core exception: Bad state: No element";
+static const field core::int singleException = invalid-expression "Unhandled core exception: Bad state: No element";
+static const field core::int singleExceptionMulti = invalid-expression "Unhandled core exception: Bad state: Too many elements";
+static const field core::int invalidProperty = invalid-expression "pkg/front_end/testcases/const_functions/const_functions_list_error.dart:36:12: Error: The getter 'invalidProperty' isn't defined for the class 'List<int>'.
+ - 'List' is from 'dart:core'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'invalidProperty'.
+  return x.invalidProperty;
+           ^^^^^^^^^^^^^^^";
+static const field core::int getWithIndexException = invalid-expression "Unhandled core exception: RangeError: Index out of range: index should be less than 1: 1";
+static const field core::int getWithIndexException2 = invalid-expression "Unhandled core exception: RangeError: Index out of range: index must not be negative: -1";
+static const field core::int getWithIndexException3 = invalid-expression "pkg/front_end/testcases/const_functions/const_functions_list_error.dart:54:12: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  return x[0.1];
+           ^";
+static const field core::List<core::int> constListAddException = invalid-expression "Unhandled core exception: Unsupported operation: add";
+static method firstExceptionFn() → core::int {
+  return #C1.{core::Iterable::first}{core::int};
+}
+static method lastExceptionFn() → core::int {
+  return #C1.{core::Iterable::last}{core::int};
+}
+static method singleExceptionFn() → core::int {
+  return #C1.{core::Iterable::single}{core::int};
+}
+static method singleExceptionMultiFn() → core::int {
+  return #C4.{core::Iterable::single}{core::int};
+}
+static method invalidPropertyFn() → core::int {
+  return invalid-expression "pkg/front_end/testcases/const_functions/const_functions_list_error.dart:36:12: Error: The getter 'invalidProperty' isn't defined for the class 'List<int>'.
+ - 'List' is from 'dart:core'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'invalidProperty'.
+  return x.invalidProperty;
+           ^^^^^^^^^^^^^^^" in #C4{<unresolved>}.invalidProperty as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+}
+static method getWithIndexExceptionFn() → core::int {
+  return #C5.{core::List::[]}(1){(core::int) → core::int};
+}
+static method getWithIndexExceptionFn2() → core::int {
+  return #C5.{core::List::[]}(1.{core::int::unary-}(){() → core::int}){(core::int) → core::int};
+}
+static method getWithIndexExceptionFn3() → core::int {
+  return #C5.{core::List::[]}(invalid-expression "pkg/front_end/testcases/const_functions/const_functions_list_error.dart:54:12: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  return x[0.1];
+           ^" in 0.1 as{TypeError,ForNonNullableByDefault} core::int){(core::int) → core::int};
+}
+static method constListAddExceptionFn() → core::List<core::int> {
+  #C4.{core::List::add}(3){(core::int) → void};
+  return #C4;
+}
+static method main() → void {}
+
+constants  {
+  #C1 = <core::int*>[]
+  #C2 = 1
+  #C3 = 2
+  #C4 = <core::int*>[#C2, #C3]
+  #C5 = <core::int*>[#C2]
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_local_functions.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_local_functions.dart.weak.modular.expect
new file mode 100644
index 0000000..4c5f0e1
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_local_functions.dart.weak.modular.expect
@@ -0,0 +1,71 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::int constTwo = #C1;
+static method function1() → core::int {
+  function add(core::int a, core::int b) → core::int
+    return a.{core::num::+}(b){(core::num) → core::int};
+  return #C2;
+}
+static method function2() → core::int {
+  function addTwo(core::int a) → core::int {
+    core::int b = a.{core::num::+}(#C1){(core::num) → core::int};
+    return b;
+  }
+  return #C3;
+}
+static method function3() → core::int {
+  function addTwoReturn(core::int a) → core::int
+    return a.{core::num::+}(#C1){(core::num) → core::int};
+  return #C4;
+}
+static method function4() → core::int {
+  function addTwo(core::int a) → core::int
+    return a.{core::num::+}(#C1){(core::num) → core::int};
+  return #C5;
+}
+static method function5() → core::int {
+  function typeFn<T extends core::Object? = dynamic>(T% a) → T%
+    return a;
+  return #C6;
+}
+static method function6() → core::int {
+  function optionalFn([core::int a = #C7]) → core::int
+    return a;
+  return #C8;
+}
+static method function7() → core::int {
+  function namedFn({core::int a = #C7}) → core::int
+    return a;
+  return #C1;
+}
+static method function8() → core::int {
+  function add(core::int a, core::int b) → core::int
+    return a.{core::num::+}(b){(core::num) → core::int};
+  return #C1.{core::num::+}(#C4){(core::num) → core::int};
+}
+static method main() → void {
+  exp::Expect::equals(self::function1(), 12);
+  exp::Expect::equals(self::function2(), 4);
+  exp::Expect::equals(self::function3(), 5);
+  exp::Expect::equals(self::function4(), 22);
+  exp::Expect::equals(self::function5(), 3);
+  exp::Expect::equals(self::function6(), 1);
+  exp::Expect::equals(self::function7(), 2);
+  exp::Expect::equals(self::function8(), 7);
+}
+
+constants  {
+  #C1 = 2
+  #C2 = 12
+  #C3 = 4
+  #C4 = 5
+  #C5 = 22
+  #C6 = 3
+  #C7 = 0
+  #C8 = 1
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_map.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_map.dart.weak.modular.expect
new file mode 100644
index 0000000..7f69cd7
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_map.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::Object? var1 = #C1;
+static const field core::Object? var2 = #C2;
+static const field core::Object? var3 = #C3;
+static const field core::Map<core::String, core::int> map = #C9;
+static const field core::Object? var4 = #C2;
+static const field core::Object? var5 = #C6;
+static const field core::Object? var6 = #C8;
+static const field core::int? var7 = #C2;
+static method fn(core::Map<core::Object, core::Object> map, core::Object key) → core::Object? {
+  return map.{core::Map::[]}(key){(core::Object?) → core::Object?};
+}
+static method fn2() → core::int? {
+  return #C11.{core::Map::[]}("key"){(core::Object?) → core::int?};
+}
+static method main() → void {
+  exp::Expect::equals(#C1, "val");
+  exp::Expect::equals(#C2, 2);
+  exp::Expect::equals(#C3, null);
+  exp::Expect::equals(#C2, 2);
+  exp::Expect::equals(#C6, 3);
+  exp::Expect::equals(#C8, 4);
+  exp::Expect::equals(#C2, 2);
+}
+
+constants  {
+  #C1 = "val"
+  #C2 = 2
+  #C3 = null
+  #C4 = "key1"
+  #C5 = "key2"
+  #C6 = 3
+  #C7 = "key3"
+  #C8 = 4
+  #C9 = <core::String*, core::int*>{#C4:#C2, #C5:#C6, #C7:#C8)
+  #C10 = "key"
+  #C11 = <core::String*, core::int*>{#C10:#C2)
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_recursion.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_recursion.dart.weak.modular.expect
new file mode 100644
index 0000000..1ee9329
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_recursion.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::int b = #C1;
+static method fn(core::int a) → core::int {
+  if(a =={core::num::==}{(core::Object) → core::bool} 1)
+    return 1;
+  return a.{core::num::*}(self::fn(a.{core::num::-}(1){(core::num) → core::int})){(core::num) → core::int};
+}
+static method localTest() → core::int {
+  function fnLocal(core::int a) → core::int {
+    if(a =={core::num::==}{(core::Object) → core::bool} 1)
+      return 1;
+    return a.{core::num::*}(fnLocal(a.{core::num::-}(1){(core::num) → core::int}){(core::int) → core::int}){(core::num) → core::int};
+  }
+  return #C1;
+}
+static method main() → void {
+  exp::Expect::equals(#C1, 24);
+  exp::Expect::equals(self::localTest(), 24);
+}
+
+constants  {
+  #C1 = 24
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_return.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_return.dart.weak.modular.expect
new file mode 100644
index 0000000..de04a6c
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_return.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field void var1 = #C1;
+static const field void var2 = #C1;
+static const field core::int? var3 = #C1;
+static const field core::int? var4 = #C1;
+static const field core::int var5 = #C2;
+static method fn() → void {}
+static method fn2() → void {
+  return;
+}
+static method fn3() → core::int?
+  return null;
+static method fn4() → core::int? {
+  return null;
+}
+static method fn5() → core::int {
+  try {
+    return throw 1;
+  }
+  on core::int catch(no-exception-var) {
+    return 2;
+  }
+}
+static method main() → void {
+  exp::Expect::equals(#C1 as{ForNonNullableByDefault} dynamic, null);
+  exp::Expect::equals(#C1 as{ForNonNullableByDefault} dynamic, null);
+  exp::Expect::equals(#C1, null);
+  exp::Expect::equals(#C1, null);
+  exp::Expect::equals(#C2, 2);
+}
+
+constants  {
+  #C1 = null
+  #C2 = 2
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_simple_invocations.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_simple_invocations.dart.weak.modular.expect
new file mode 100644
index 0000000..04bf4ef
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_simple_invocations.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::int binary = #C1;
+static const field core::int optional = #C2;
+static const field core::int optional1 = #C3;
+static const field core::int named = #C4;
+static const field core::int named1 = #C5;
+static const field core::int type = #C6;
+static const field core::String str = #C7;
+static const field core::bool eq = #C8;
+static const field core::int negative = #C9;
+static const field core::bool boolean = #C8;
+static const field core::double doubleResult = #C10;
+static const field core::int multi = #C2;
+static const field core::int multi2 = #C3;
+static method binaryFn(core::int a, core::int b) → core::int
+  return a.{core::num::-}(b){(core::num) → core::int};
+static method optionalFn(core::int c, [core::int d = #C11]) → core::int
+  return c.{core::num::+}(d){(core::num) → core::int};
+static method namedFn(core::int e, {core::int f = #C3}) → core::int
+  return e.{core::num::+}(f){(core::num) → core::int};
+static method typeFn<T extends core::Object? = dynamic>(self::typeFn::T% x) → self::typeFn::T%
+  return x;
+static method stringFn(core::String s) → core::String
+  return s.{core::String::+}("ing"){(core::String) → core::String};
+static method equalFn(core::int a, core::int b) → core::bool
+  return a =={core::num::==}{(core::Object) → core::bool} b;
+static method unary(core::int a) → core::int
+  return a.{core::int::unary-}(){() → core::int};
+static method boolFn(core::bool a, core::bool b) → core::bool
+  return a || b;
+static method doubleFn(core::double a, core::double b) → core::double
+  return a.{core::double::*}(b){(core::num) → core::double};
+static method multiFn(core::int a) → core::int
+  return a.{core::num::+}(1){(core::num) → core::int};
+static method main() → void {
+  exp::Expect::equals(#C1, 1);
+  exp::Expect::equals(#C2, 2);
+  exp::Expect::equals(#C3, 3);
+  exp::Expect::equals(#C4, 4);
+  exp::Expect::equals(#C5, 5);
+  exp::Expect::equals(#C6, 6);
+  exp::Expect::equals(#C7, "string");
+  exp::Expect::equals(#C8, true);
+  exp::Expect::equals(#C9, 2.{core::int::unary-}(){() → core::int});
+  exp::Expect::equals(#C8, true);
+  exp::Expect::equals(#C10, 4.4);
+  exp::Expect::equals(#C2, 2);
+  exp::Expect::equals(#C3, 3);
+}
+
+constants  {
+  #C1 = 1
+  #C2 = 2
+  #C3 = 3
+  #C4 = 4
+  #C5 = 5
+  #C6 = 6
+  #C7 = "string"
+  #C8 = true
+  #C9 = -2
+  #C10 = 4.4
+  #C11 = 0
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_string.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_string.dart.weak.modular.expect
new file mode 100644
index 0000000..21293b7
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_string.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::String str = #C1;
+static const field core::String var1 = #C2;
+static const field dynamic var2 = #C3;
+static const field core::String var3 = #C3;
+static const field dynamic var4 = #C4;
+static method fn() → dynamic {
+  core::String local = "str";
+  return local.{core::String::[]}(0){(core::int) → core::String};
+}
+static method fn2() → dynamic {
+  try {
+    core::String x = #C1.{core::String::[]}(1.{core::int::unary-}(){() → core::int}){(core::int) → core::String};
+  }
+  on core::RangeError catch(no-exception-var) {
+    return 2;
+  }
+}
+static method main() → void {
+  exp::Expect::equals(#C2, "r");
+  exp::Expect::equals(#C3, "s");
+  exp::Expect::equals(#C3, "s");
+  exp::Expect::equals(#C4, 2);
+}
+
+constants  {
+  #C1 = "str"
+  #C2 = "r"
+  #C3 = "s"
+  #C4 = 2
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_string_error.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_string_error.dart.weak.modular.expect
new file mode 100644
index 0000000..eeab2cc
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_string_error.dart.weak.modular.expect
@@ -0,0 +1,68 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/const_functions/const_functions_string_error.dart:28:14: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//   return str[1.1];
+//              ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_string_error.dart:10:17: Error: Constant evaluation error:
+// const var1 = str[-1];
+//                 ^
+// pkg/front_end/testcases/const_functions/const_functions_string_error.dart:10:17: Context: Unhandled core exception: RangeError: Index out of range: index must not be negative: -1
+// const var1 = str[-1];
+//                 ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_string_error.dart:11:17: Error: Constant evaluation error:
+// const var2 = str[3];
+//                 ^
+// pkg/front_end/testcases/const_functions/const_functions_string_error.dart:11:17: Context: Unhandled core exception: RangeError: Index out of range: index should be less than 3: 3
+// const var2 = str[3];
+//                 ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_string_error.dart:13:14: Error: Constant evaluation error:
+// const var3 = fn();
+//              ^
+// pkg/front_end/testcases/const_functions/const_functions_string_error.dart:16:13: Context: Unhandled core exception: RangeError: Index out of range: index must not be negative: -1
+//   return str[-1];
+//             ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_string_error.dart:19:14: Error: Constant evaluation error:
+// const var4 = fn2();
+//              ^
+// pkg/front_end/testcases/const_functions/const_functions_string_error.dart:22:13: Context: Unhandled core exception: RangeError: Index out of range: index should be less than 3: 3
+//   return str[3];
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "package:expect/expect.dart";
+
+static const field core::String str = #C1;
+static const field core::String var1 = invalid-expression "Unhandled core exception: RangeError: Index out of range: index must not be negative: -1";
+static const field core::String var2 = invalid-expression "Unhandled core exception: RangeError: Index out of range: index should be less than 3: 3";
+static const field dynamic var3 = invalid-expression "Unhandled core exception: RangeError: Index out of range: index must not be negative: -1";
+static const field dynamic var4 = invalid-expression "Unhandled core exception: RangeError: Index out of range: index should be less than 3: 3";
+static const field dynamic var5 = invalid-expression "pkg/front_end/testcases/const_functions/const_functions_string_error.dart:28:14: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  return str[1.1];
+             ^";
+static method fn() → dynamic {
+  core::String s = "str";
+  return #C1.{core::String::[]}(1.{core::int::unary-}(){() → core::int}){(core::int) → core::String};
+}
+static method fn2() → dynamic {
+  core::String s = "str";
+  return #C1.{core::String::[]}(3){(core::int) → core::String};
+}
+static method fn3() → dynamic {
+  core::String s = "str";
+  return #C1.{core::String::[]}(invalid-expression "pkg/front_end/testcases/const_functions/const_functions_string_error.dart:28:14: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  return str[1.1];
+             ^" in 1.1 as{TypeError,ForNonNullableByDefault} core::int){(core::int) → core::String};
+}
+static method main() → void {}
+
+constants  {
+  #C1 = "str"
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_switch_statements.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_switch_statements.dart.weak.modular.expect
new file mode 100644
index 0000000..b3f761c
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_switch_statements.dart.weak.modular.expect
@@ -0,0 +1,93 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::int var1 = #C1;
+static const field core::int var2 = #C2;
+static const field core::int var3 = #C1;
+static const field core::int var4 = #C1;
+static const field core::int var5 = #C3;
+static const field core::int var6 = #C4;
+static const field core::int var7 = #C5;
+static const field core::int var8 = #C6;
+static const field core::int var9 = #C3;
+static method basicSwitch(core::int x) → core::int {
+  #L1:
+  switch(x) {
+    #L2:
+    case #C7:
+      {
+        return 100;
+      }
+    #L3:
+    default:
+      {
+        x = x.{core::num::+}(1){(core::num) → core::int};
+        break #L1;
+      }
+  }
+  return x;
+}
+static method multipleCaseSwitch(core::int x) → core::int {
+  #L4:
+  switch(x) {
+    #L5:
+    case #C7:
+    case #C8:
+      {
+        return 100;
+      }
+    #L6:
+    default:
+      {
+        break #L4;
+      }
+  }
+  return 0;
+}
+static method continueLabelSwitch(core::int x) → core::int {
+  switch(x) {
+    #L7:
+    case #C7:
+      {
+        x = x.{core::num::+}(100){(core::num) → core::int};
+        continue #L8;
+      }
+    #L9:
+    case #C8:
+      {
+        continue #L7;
+      }
+    #L8:
+    case #C2:
+      {
+        return x.{core::num::+}(3){(core::num) → core::int};
+      }
+  }
+  return 0;
+}
+static method main() → void {
+  exp::Expect::equals(#C1, 100);
+  exp::Expect::equals(#C2, 3);
+  exp::Expect::equals(#C1, 100);
+  exp::Expect::equals(#C1, 100);
+  exp::Expect::equals(#C3, 0);
+  exp::Expect::equals(#C4, 104);
+  exp::Expect::equals(#C5, 105);
+  exp::Expect::equals(#C6, 6);
+  exp::Expect::equals(#C3, 0);
+}
+
+constants  {
+  #C1 = 100
+  #C2 = 3
+  #C3 = 0
+  #C4 = 104
+  #C5 = 105
+  #C6 = 6
+  #C7 = 1
+  #C8 = 2
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_try_catch_finally.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_try_catch_finally.dart.weak.modular.expect
new file mode 100644
index 0000000..f816401
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_try_catch_finally.dart.weak.modular.expect
@@ -0,0 +1,137 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::int var1 = #C1;
+static const field core::int var2 = #C2;
+static const field core::int var3 = #C3;
+static const field core::int var4 = #C2;
+static const field core::int var5 = #C4;
+static const field core::int var6 = #C4;
+static const field core::int var7 = #C4;
+static const field core::int var8 = #C4;
+static const field core::int var9 = #C4;
+static const field core::int var10 = #C1;
+static const field core::int var11 = #C1;
+static const field core::String var12 = #C5;
+static const field core::int var13 = #C2;
+static method fn(dynamic error) → core::int {
+  try {
+    throw error;
+  }
+  on core::String catch(no-exception-var) {
+    return 0;
+  }
+  on core::Object catch(final core::Object e) {
+    return 1;
+  }
+}
+static method fn1(dynamic error) → core::int {
+  try {
+    throw error;
+  }
+  on core::int catch(final core::int e) {
+    return e;
+  }
+  on core::Object catch(final core::Object e) {
+    return 1;
+  }
+}
+static method finallyReturn(dynamic error) → core::int {
+  try
+    try {
+      if(!(error =={core::Object::==}{(core::Object) → core::bool} 1))
+        throw error;
+    }
+    on core::int catch(final core::int e) {
+      return e;
+    }
+    on core::Object catch(final core::Object e) {
+      return 1;
+    }
+  finally {
+    return 100;
+  }
+}
+static method finallyReturn1(core::int x) → core::int {
+  try {
+    if(x =={core::num::==}{(core::Object) → core::bool} 1) {
+      throw x;
+    }
+    else {
+      return 0;
+    }
+  }
+  finally {
+    return 100;
+  }
+}
+static method finallyMutate() → core::int {
+  core::int x = 0;
+  try {
+    return x;
+  }
+  finally {
+    x = x.{core::num::+}(1){(core::num) → core::int};
+  }
+}
+static method subtypeFn() → core::int {
+  try {
+    throw 2.5;
+  }
+  on core::num catch(final core::num e) {
+    return 0;
+  }
+}
+static method orderFn() → core::String {
+  core::String x = "st";
+  try
+    try {
+      x = x.{core::String::+}("ri"){(core::String) → core::String};
+      throw 2;
+    }
+    on core::Object catch(final core::Object e) {
+      x = x.{core::String::+}("n"){(core::String) → core::String};
+    }
+  finally {
+    return x.{core::String::+}("g"){(core::String) → core::String};
+  }
+}
+static method notThrowStatement() → core::int {
+  core::int count = 0;
+  try {
+    for (core::int i = 0; i.{core::num::<}(1){(core::num) → core::bool}; throw "a") {
+      count = count.{core::num::+}(i){(core::num) → core::int};
+    }
+  }
+  on core::Object catch(final core::Object e) {
+    return 1;
+  }
+  return 0;
+}
+static method main() → void {
+  exp::Expect::equals(#C1, 0);
+  exp::Expect::equals(#C2, 1);
+  exp::Expect::equals(#C3, 10);
+  exp::Expect::equals(#C2, 1);
+  exp::Expect::equals(#C4, 100);
+  exp::Expect::equals(#C4, 100);
+  exp::Expect::equals(#C4, 100);
+  exp::Expect::equals(#C4, 100);
+  exp::Expect::equals(#C4, 100);
+  exp::Expect::equals(#C1, 0);
+  exp::Expect::equals(#C1, 0);
+  exp::Expect::equals(#C5, "string");
+  exp::Expect::equals(#C2, 1);
+}
+
+constants  {
+  #C1 = 0
+  #C2 = 1
+  #C3 = 10
+  #C4 = 100
+  #C5 = "string"
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart.weak.modular.expect
new file mode 100644
index 0000000..233c4ee
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart.weak.modular.expect
@@ -0,0 +1,78 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart:9:14: Error: Constant evaluation error:
+// const var1 = finallyThrow(0);
+//              ^
+// pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart:19:5: Context: Unhandled exception: 2
+//     throw 2;
+//     ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart:10:14: Error: Constant evaluation error:
+// const var2 = finallyThrow(1);
+//              ^
+// pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart:19:5: Context: Unhandled exception: 2
+//     throw 2;
+//     ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart:23:14: Error: Constant evaluation error:
+// const var3 = unhandledThrow(0);
+//              ^
+// pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart:27:5: Context: Unhandled exception: 0
+//     throw x;
+//     ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart:24:14: Error: Constant evaluation error:
+// const var4 = unhandledThrow("string");
+//              ^
+// pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart:29:5: Context: Unhandled exception: "string"
+//     throw e;
+//     ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart:33:14: Error: Constant evaluation error:
+// const var5 = unhandledThrow2();
+//              ^
+// pkg/front_end/testcases/const_functions/const_functions_try_catch_finally_error.dart:36:26: Context: Unhandled exception: "a"
+//   for (int i = 0; i < 1; throw 'a') {
+//                          ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "package:expect/expect.dart";
+
+static const field core::int var1 = invalid-expression "Unhandled exception: 2";
+static const field core::int var2 = invalid-expression "Unhandled exception: 2";
+static const field core::int var3 = invalid-expression "Unhandled exception: 0";
+static const field core::int var4 = invalid-expression "Unhandled exception: \"string\"";
+static const field core::int var5 = invalid-expression "Unhandled exception: \"a\"";
+static method finallyThrow(core::int x) → core::int {
+  try {
+    if(x =={core::num::==}{(core::Object) → core::bool} 1) {
+      throw x;
+    }
+    else {
+      return 0;
+    }
+  }
+  finally {
+    throw 2;
+  }
+}
+static method unhandledThrow(dynamic x) → core::int {
+  try {
+    throw x;
+  }
+  on core::String catch(final core::String e) {
+    throw e;
+  }
+}
+static method unhandledThrow2() → core::int {
+  core::int count = 0;
+  for (core::int i = 0; i.{core::num::<}(1){(core::num) → core::bool}; throw "a") {
+    count = count.{core::num::+}(i){(core::num) → core::int};
+  }
+  return 0;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_variable_assignments.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_variable_assignments.dart.weak.modular.expect
new file mode 100644
index 0000000..704d914
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_variable_assignments.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::int var1 = #C1;
+static const field core::int var3 = #C2;
+static const field core::int var4 = #C1;
+static method varAssignmentTest(core::int a) → core::int {
+  core::int x = 4;
+  {
+    x = 3;
+  }
+  return x;
+}
+static method function() → core::int {
+  function varAssignmentTest2() → core::int {
+    core::int x = 2;
+    x = x.{core::num::+}(1){(core::num) → core::int};
+    return x;
+  }
+  return #C1;
+}
+static method varAssignmentTest3(core::int a) → core::int {
+  core::int x = 4;
+  x = a.{core::num::+}(1){(core::num) → core::int};
+  return x;
+}
+static method main() → void {
+  exp::Expect::equals(#C1, 3);
+  exp::Expect::equals(self::function(), 3);
+  exp::Expect::equals(#C2, 2);
+  exp::Expect::equals(#C1, 3);
+}
+
+constants  {
+  #C1 = 3
+  #C2 = 2
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_variable_declarations.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_variable_declarations.dart.weak.modular.expect
new file mode 100644
index 0000000..c8a68f5
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_variable_declarations.dart.weak.modular.expect
@@ -0,0 +1,81 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::int var1 = #C1;
+static const field core::int var1_1 = #C2;
+static const field core::String var2 = #C3;
+static const field core::int var3 = #C4;
+static const field core::int var4 = #C5;
+static const field core::int var5 = #C6;
+static const field core::int var6 = #C5;
+static const field core::int var7 = #C5;
+static const field core::int var8 = #C5;
+static const field core::int? var9 = #C7;
+static method function1(core::int a, core::int b) → core::int {
+  core::int x = 1.{core::num::+}(a){(core::num) → core::int}.{core::num::+}(b){(core::num) → core::int};
+  return x;
+}
+static method function2() → core::String {
+  dynamic x = "string";
+  return x as{TypeError,ForDynamic,ForNonNullableByDefault} core::String;
+}
+static method function3() → core::int {
+  core::int first = 2;
+  core::int second = 2.{core::num::+}(first){(core::num) → core::int};
+  return 2.{core::num::+}(second){(core::num) → core::int};
+}
+static method function4() → core::int {
+  core::int first = 2;
+  core::int second = 0;
+  return first.{core::num::+}(second){(core::num) → core::int};
+}
+static method function5() → core::int {
+  return #C6;
+}
+static method function6() → core::int {
+  dynamic a;
+  a = 2;
+  return a as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+}
+static method function7() → core::int {
+  dynamic a;
+  dynamic b;
+  a = 2;
+  return a as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+}
+static method function8() → core::int {
+  dynamic a;
+  core::int? b;
+  a = 2;
+  return a as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+}
+static method function9() → core::int? {
+  core::int? x;
+  return x;
+}
+static method main() → void {
+  exp::Expect::equals(#C1, 4);
+  exp::Expect::equals(#C2, 5);
+  exp::Expect::equals(#C3, "string");
+  exp::Expect::equals(#C4, 6);
+  exp::Expect::equals(#C5, 2);
+  exp::Expect::equals(#C6, 2.{core::int::unary-}(){() → core::int});
+  exp::Expect::equals(#C5, 2);
+  exp::Expect::equals(#C5, 2);
+  exp::Expect::equals(#C5, 2);
+  exp::Expect::equals(#C7, null);
+}
+
+constants  {
+  #C1 = 4
+  #C2 = 5
+  #C3 = "string"
+  #C4 = 6
+  #C5 = 2
+  #C6 = -2
+  #C7 = null
+}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_variable_declarations_error.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_variable_declarations_error.dart.weak.modular.expect
new file mode 100644
index 0000000..9d6fa65
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_variable_declarations_error.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/const_functions/const_functions_variable_declarations_error.dart:9:14: Error: Constant evaluation error:
+// const var1 = fn1();
+//              ^
+// pkg/front_end/testcases/const_functions/const_functions_variable_declarations_error.dart:10:8: Context: Expected constant 'null' to be of type 'int', but was of type 'Null'.
+// int fn1() {
+//        ^
+// pkg/front_end/testcases/const_functions/const_functions_variable_declarations_error.dart:9:7: Context: While analyzing:
+// const var1 = fn1();
+//       ^
+//
+// pkg/front_end/testcases/const_functions/const_functions_variable_declarations_error.dart:15:14: Error: Constant evaluation error:
+// const var2 = fn2();
+//              ^
+// pkg/front_end/testcases/const_functions/const_functions_variable_declarations_error.dart:19:10: Context: Expected constant '"string"' to be of type 'int', but was of type 'String'.
+//   return x;
+//          ^
+// pkg/front_end/testcases/const_functions/const_functions_variable_declarations_error.dart:15:7: Context: While analyzing:
+// const var2 = fn2();
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "package:expect/expect.dart";
+
+static const field core::int var1 = invalid-expression "Expected constant 'null' to be of type 'int', but was of type 'Null'.";
+static const field core::int var2 = invalid-expression "Expected constant '\"string\"' to be of type 'int', but was of type 'String'.";
+static method fn1() → core::int {
+  dynamic a;
+  return a as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+}
+static method fn2() → core::int {
+  dynamic x;
+  x = "string";
+  return x as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/const_functions/const_functions_while_statements.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/const_functions_while_statements.dart.weak.modular.expect
new file mode 100644
index 0000000..b96eb2b
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/const_functions_while_statements.dart.weak.modular.expect
@@ -0,0 +1,100 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static const field core::int var1 = #C1;
+static const field core::int var2 = #C2;
+static const field core::int var3 = #C3;
+static const field core::int var4 = #C4;
+static const field core::int var5 = #C1;
+static const field core::int var6 = #C5;
+static const field core::int var7 = #C2;
+static const field core::int var8 = #C6;
+static const field core::int var9 = #C7;
+static method fn(core::int a) → core::int {
+  core::int b = a;
+  core::int i = 0;
+  while (i.{core::num::<}(2){(core::num) → core::bool}) {
+    b = b.{core::num::+}(a){(core::num) → core::int};
+    i = i.{core::num::+}(1){(core::num) → core::int};
+  }
+  return b;
+}
+static method fn1(core::int a) → core::int {
+  core::int b = a;
+  while (true) {
+    b = b.{core::num::*}(3){(core::num) → core::int};
+    if(b.{core::num::>}(10){(core::num) → core::bool})
+      return b;
+  }
+}
+static method fnContinue() → core::int {
+  core::int a = 0;
+  core::int i = 0;
+  while (i.{core::num::<}(5){(core::num) → core::bool})
+    #L1:
+    {
+      if(i.{core::num::%}(2){(core::num) → core::int} =={core::num::==}{(core::Object) → core::bool} 1) {
+        i = i.{core::num::+}(1){(core::num) → core::int};
+        break #L1;
+      }
+      a = a.{core::num::+}(i){(core::num) → core::int};
+      i = i.{core::num::+}(1){(core::num) → core::int};
+    }
+  return a;
+}
+static method fnBreak(core::int a) → core::int {
+  core::int b = a;
+  core::int i = 0;
+  #L2:
+  while (i.{core::num::<}(2){(core::num) → core::bool}) {
+    if(b =={core::num::==}{(core::Object) → core::bool} 2)
+      break #L2;
+    b = b.{core::num::+}(a){(core::num) → core::int};
+    i = i.{core::num::+}(1){(core::num) → core::int};
+  }
+  return b;
+}
+static method fnNestedWhile() → core::int {
+  core::int a = 0;
+  while (true) {
+    #L3:
+    while (true) {
+      break #L3;
+    }
+    return 1;
+  }
+}
+static method fnBreakLabel() → core::int {
+  #L4:
+  while (true) {
+    while (true) {
+      break #L4;
+    }
+  }
+  return 3;
+}
+static method main() → void {
+  exp::Expect::equals(#C1, 6);
+  exp::Expect::equals(#C2, 9);
+  exp::Expect::equals(#C3, 18);
+  exp::Expect::equals(#C4, 27);
+  exp::Expect::equals(#C1, 6);
+  exp::Expect::equals(#C5, 2);
+  exp::Expect::equals(#C2, 9);
+  exp::Expect::equals(#C6, 1);
+  exp::Expect::equals(#C7, 3);
+}
+
+constants  {
+  #C1 = 6
+  #C2 = 9
+  #C3 = 18
+  #C4 = 27
+  #C5 = 2
+  #C6 = 1
+  #C7 = 3
+}
diff --git a/pkg/front_end/testcases/const_functions/non_function_invocation.dart.weak.modular.expect b/pkg/front_end/testcases/const_functions/non_function_invocation.dart.weak.modular.expect
new file mode 100644
index 0000000..a98efbd
--- /dev/null
+++ b/pkg/front_end/testcases/const_functions/non_function_invocation.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/const_functions/non_function_invocation.dart:6:20: Error: Constant evaluation error:
+// const dynamic b = a();
+//                    ^
+// pkg/front_end/testcases/const_functions/non_function_invocation.dart:6:20: Context: Null value during constant evaluation.
+// const dynamic b = a();
+//                    ^
+// pkg/front_end/testcases/const_functions/non_function_invocation.dart:6:15: Context: While analyzing:
+// const dynamic b = a();
+//               ^
+//
+import self as self;
+
+static const field dynamic a = #C1;
+static const field dynamic b = invalid-expression "Null value during constant evaluation.";
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/abstract_class_constructor_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/abstract_class_constructor_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..98579c4
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/abstract_class_constructor_tear_off.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/abstract_class_constructor_tear_off.dart:14:17: Error: Constructors on abstract classes can't be torn off.
+//   AbstractClass.new; // error
+//                 ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/abstract_class_constructor_tear_off.dart:15:9: Error: Member not found: 'new'.
+//   Mixin.new; // error
+//         ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/abstract_class_constructor_tear_off.dart:17:33: Error: Constructors on abstract classes can't be torn off.
+//   AbstractNamedMixinApplication.new; // error
+//                                 ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/abstract_class_constructor_tear_off.dart:18:13: Error: Member not found: 'new'.
+//   Extension.new; // error
+//             ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class ConcreteClass extends core::Object {
+  synthetic constructor •() → self::ConcreteClass
+    : super core::Object::•()
+    ;
+}
+abstract class AbstractClass extends core::Object {
+  synthetic constructor •() → self::AbstractClass
+    : super core::Object::•()
+    ;
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+}
+class NamedMixinApplication = core::Object with self::Mixin /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::NamedMixinApplication
+    : super core::Object::•()
+    ;
+}
+abstract class AbstractNamedMixinApplication = core::Object with self::Mixin /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::AbstractNamedMixinApplication
+    : super core::Object::•()
+    ;
+}
+extension Extension on core::int {
+}
+static method test() → dynamic {
+  #C1;
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/abstract_class_constructor_tear_off.dart:14:17: Error: Constructors on abstract classes can't be torn off.
+  AbstractClass.new; // error
+                ^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/abstract_class_constructor_tear_off.dart:15:9: Error: Member not found: 'new'.
+  Mixin.new; // error
+        ^^^";
+  #C2;
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/abstract_class_constructor_tear_off.dart:17:33: Error: Constructors on abstract classes can't be torn off.
+  AbstractNamedMixinApplication.new; // error
+                                ^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/abstract_class_constructor_tear_off.dart:18:13: Error: Member not found: 'new'.
+  Extension.new; // error
+            ^^^";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::ConcreteClass::•
+  #C2 = constructor-tearoff self::NamedMixinApplication::•
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/bound_checks_in_type_literals.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/bound_checks_in_type_literals.dart.weak.modular.expect
new file mode 100644
index 0000000..0494323
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/bound_checks_in_type_literals.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/bound_checks_in_type_literals.dart:11:20: Error: Type argument 'Object' doesn't conform to the bound 'num' of the type variable 'T' on 'C'.
+//  - 'Object' is from 'dart:core'.
+// Try changing type arguments so that they conform to the bounds.
+// var test3 = (() => C<Object>)();
+//                    ^
+// pkg/front_end/testcases/constructor_tearoffs/bound_checks_in_type_literals.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class C<T extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/bound_checks_in_type_literals.dart:7:11: Error: Type argument 'Object' doesn't conform to the bound 'num' of the type variable 'T' on 'C'.
+//  - 'Object' is from 'dart:core'.
+// Try changing type arguments so that they conform to the bounds.
+// test() => C<Object>;
+//           ^
+// pkg/front_end/testcases/constructor_tearoffs/bound_checks_in_type_literals.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class C<T extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/bound_checks_in_type_literals.dart:9:17: Error: Type argument 'Object' doesn't conform to the bound 'num' of the type variable 'T' on 'C'.
+//  - 'Object' is from 'dart:core'.
+// Try changing type arguments so that they conform to the bounds.
+// test2([Type t = C<Object>]) {}
+//                 ^
+// pkg/front_end/testcases/constructor_tearoffs/bound_checks_in_type_literals.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class C<T extends num> {}
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::num> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T>
+    : super core::Object::•()
+    ;
+}
+static field core::Type test3 = (() → core::Type => #C1)(){() → core::Type};
+static method test() → dynamic
+  return #C1;
+static method test2([core::Type t = #C1]) → dynamic {}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = TypeLiteralConstant(self::C<core::Object*>*)
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/call_instantiation.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/call_instantiation.dart.weak.modular.expect
new file mode 100644
index 0000000..6e425f6
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/call_instantiation.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/call_instantiation.dart:11:31: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Function'.
+//  - 'Function' is from 'dart:core'.
+// Try changing the operand or remove the type arguments.
+//   int Function(int) g = f.call<int>;
+//                               ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field <T extends core::Object? = dynamic>(T%) → T% funcValue = #C1;
+static field (core::int) → core::int f = self::funcValue.call<core::int>;
+static field (core::int) → core::int g = self::funcValue.call<core::int>;
+static method func<T extends core::Object? = dynamic>(self::func::T% value) → self::func::T%
+  return value;
+static method test(core::Function f) → dynamic {
+  (core::int) → core::int g = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/call_instantiation.dart:11:31: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Function'.
+ - 'Function' is from 'dart:core'.
+Try changing the operand or remove the type arguments.
+  int Function(int) g = f.call<int>;
+                              ^";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::func
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart.weak.modular.expect
new file mode 100644
index 0000000..bb11cff
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart.weak.modular.expect
@@ -0,0 +1,319 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:29:5: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Class?'.
+//  - 'Class' is from 'pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart'.
+// Try changing the operand or remove the type arguments.
+//   c1<int>; // error
+//     ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:30:5: Error: The static type of the explicit instantiation operand must be a generic function type but is 'GetterCall'.
+//  - 'GetterCall' is from 'pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart'.
+// Try changing the operand or remove the type arguments.
+//   c2<int>; // error
+//     ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:31:4: Error: The static type of the explicit instantiation operand must be a generic function type but is 'int?'.
+// Try changing the operand or remove the type arguments.
+//   i<int>; // error
+//    ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:32:5: Error: The static type of the explicit instantiation operand must be a generic function type but is 'T'.
+// Try changing the operand or remove the type arguments.
+//   t1<int>; // error
+//     ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:33:5: Error: The static type of the explicit instantiation operand must be a generic function type but is 'T?'.
+// Try changing the operand or remove the type arguments.
+//   t2<int>; // error
+//     ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:34:4: Error: The static type of the explicit instantiation operand must be a generic function type but is 'S?'.
+// Try changing the operand or remove the type arguments.
+//   s<int>; // error
+//    ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:35:5: Error: The static type of the explicit instantiation operand must be a non-null generic function type but is 'void Function<T>()?'.
+// Try changing the operand or remove the type arguments.
+//   f1<int>; // error
+//     ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:36:4: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Never'.
+// Try changing the operand or remove the type arguments.
+//   n<int>; // error
+//    ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:37:4: Error: The static type of the explicit instantiation operand must be a generic function type but is 'dynamic'.
+// Try changing the operand or remove the type arguments.
+//   d<int>; // error
+//    ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:38:4: Error: The static type of the explicit instantiation operand must be a generic function type but is 'String'.
+// Try changing the operand or remove the type arguments.
+//   a<int>; // error
+//    ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:39:4: Error: The static type of the explicit instantiation operand must be a generic function type but is 'double'.
+// Try changing the operand or remove the type arguments.
+//   b<int>; // error
+//    ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:40:4: Error: The static type of the explicit instantiation operand must be a generic function type but is 'bool'.
+// Try changing the operand or remove the type arguments.
+//   c<int>; // error
+//    ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:41:5: Error: The static type of the explicit instantiation operand must be a generic function type but is 'FutureOr<Class>'.
+//  - 'Class' is from 'pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart'.
+// Try changing the operand or remove the type arguments.
+//   f2<int>; // error
+//     ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:42:5: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Function'.
+//  - 'Function' is from 'dart:core'.
+// Try changing the operand or remove the type arguments.
+//   f3<int>; // error
+//     ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:61:19: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Class?'.
+//  - 'Class' is from 'pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart'.
+// Try changing the operand or remove the type arguments.
+// var topLevel3 = c2<int>; // error
+//                   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:62:19: Error: The static type of the explicit instantiation operand must be a generic function type but is 'GetterCall'.
+//  - 'GetterCall' is from 'pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart'.
+// Try changing the operand or remove the type arguments.
+// var topLevel4 = c3<int>; // error
+//                   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:63:19: Error: The static type of the explicit instantiation operand must be a generic function type but is 'int?'.
+// Try changing the operand or remove the type arguments.
+// var topLevel5 = i2<int>; // error
+//                   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:64:19: Error: The static type of the explicit instantiation operand must be a non-null generic function type but is 'void Function<T>()?'.
+// Try changing the operand or remove the type arguments.
+// var topLevel6 = f1<int>; // error
+//                   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:65:18: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Never'.
+// Try changing the operand or remove the type arguments.
+// var topLevel7 = n<int>; // error
+//                  ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:66:18: Error: The static type of the explicit instantiation operand must be a generic function type but is 'dynamic'.
+// Try changing the operand or remove the type arguments.
+// var topLevel8 = d<int>; // error
+//                  ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:67:18: Error: The static type of the explicit instantiation operand must be a generic function type but is 'String'.
+// Try changing the operand or remove the type arguments.
+// var topLevel9 = a<int>; // error
+//                  ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:68:19: Error: The static type of the explicit instantiation operand must be a generic function type but is 'double'.
+// Try changing the operand or remove the type arguments.
+// var topLevel10 = b<int>; // error
+//                   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:69:19: Error: The static type of the explicit instantiation operand must be a generic function type but is 'bool'.
+// Try changing the operand or remove the type arguments.
+// var topLevel11 = c<int>; // error
+//                   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:70:20: Error: The static type of the explicit instantiation operand must be a generic function type but is 'FutureOr<Class>'.
+//  - 'Class' is from 'pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart'.
+// Try changing the operand or remove the type arguments.
+// var topLevel12 = f2<int>; // error
+//                    ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:71:20: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Function'.
+//  - 'Function' is from 'dart:core'.
+// Try changing the operand or remove the type arguments.
+// var topLevel13 = f3<int>; // error
+//                    ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  method call<T extends core::Object? = dynamic>() → dynamic {}
+}
+class GetterCall extends core::Object {
+  synthetic constructor •() → self::GetterCall
+    : super core::Object::•()
+    ;
+  get call() → <T extends core::Object? = dynamic>() → void
+    return <T extends core::Object? = dynamic>() → void {};
+}
+extension Extension on core::int {
+  method call = self::Extension|call;
+  tearoff call = self::Extension|get#call;
+}
+extension ExtensionGetter on core::double {
+  get call = self::ExtensionGetter|get#call;
+}
+extension ExtensionSetter on core::bool {
+  set call = self::ExtensionSetter|set#call;
+}
+extension Ambiguous1 on core::String {
+  method call = self::Ambiguous1|call;
+  tearoff call = self::Ambiguous1|get#call;
+}
+extension Ambiguous2 on core::String {
+  method call = self::Ambiguous2|call;
+  tearoff call = self::Ambiguous2|get#call;
+}
+static field self::Class c1 = new self::Class::•();
+static field self::Class? c2;
+static field self::GetterCall c3 = new self::GetterCall::•();
+static field core::int i1 = 0;
+static field core::int? i2 = null;
+static field <T extends core::Object? = dynamic>() →? void f1 = null;
+static field Never n = throw "";
+static field dynamic d = null;
+static field core::String a = "";
+static field core::double b = 0.5;
+static field core::bool c = true;
+static field FutureOr<self::Class>f2 = new self::Class::•();
+static field core::Function f3 = () → Null {};
+static field () → dynamic topLevel1 = self::c1.{self::Class::call}{<T extends core::Object? = dynamic>() → dynamic}<core::int>;
+static field () → dynamic topLevel2 = self::Extension|get#call(self::i1)<core::int>;
+static field invalid-type topLevel3 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:61:19: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Class?'.
+ - 'Class' is from 'pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart'.
+Try changing the operand or remove the type arguments.
+var topLevel3 = c2<int>; // error
+                  ^";
+static field invalid-type topLevel4 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:62:19: Error: The static type of the explicit instantiation operand must be a generic function type but is 'GetterCall'.
+ - 'GetterCall' is from 'pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart'.
+Try changing the operand or remove the type arguments.
+var topLevel4 = c3<int>; // error
+                  ^";
+static field invalid-type topLevel5 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:63:19: Error: The static type of the explicit instantiation operand must be a generic function type but is 'int?'.
+Try changing the operand or remove the type arguments.
+var topLevel5 = i2<int>; // error
+                  ^";
+static field invalid-type topLevel6 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:64:19: Error: The static type of the explicit instantiation operand must be a non-null generic function type but is 'void Function<T>()?'.
+Try changing the operand or remove the type arguments.
+var topLevel6 = f1<int>; // error
+                  ^";
+static field invalid-type topLevel7 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:65:18: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Never'.
+Try changing the operand or remove the type arguments.
+var topLevel7 = n<int>; // error
+                 ^";
+static field invalid-type topLevel8 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:66:18: Error: The static type of the explicit instantiation operand must be a generic function type but is 'dynamic'.
+Try changing the operand or remove the type arguments.
+var topLevel8 = d<int>; // error
+                 ^";
+static field invalid-type topLevel9 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:67:18: Error: The static type of the explicit instantiation operand must be a generic function type but is 'String'.
+Try changing the operand or remove the type arguments.
+var topLevel9 = a<int>; // error
+                 ^";
+static field invalid-type topLevel10 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:68:19: Error: The static type of the explicit instantiation operand must be a generic function type but is 'double'.
+Try changing the operand or remove the type arguments.
+var topLevel10 = b<int>; // error
+                  ^";
+static field invalid-type topLevel11 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:69:19: Error: The static type of the explicit instantiation operand must be a generic function type but is 'bool'.
+Try changing the operand or remove the type arguments.
+var topLevel11 = c<int>; // error
+                  ^";
+static field invalid-type topLevel12 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:70:20: Error: The static type of the explicit instantiation operand must be a generic function type but is 'FutureOr<Class>'.
+ - 'Class' is from 'pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart'.
+Try changing the operand or remove the type arguments.
+var topLevel12 = f2<int>; // error
+                   ^";
+static field invalid-type topLevel13 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:71:20: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Function'.
+ - 'Function' is from 'dart:core'.
+Try changing the operand or remove the type arguments.
+var topLevel13 = f3<int>; // error
+                   ^";
+static method method<T extends self::Class, S extends core::int>(self::Class c, core::int i, self::method::T t, self::method::S s) → dynamic {
+  c.{self::Class::call}{<T extends core::Object? = dynamic>() → dynamic}<core::int>;
+  self::Extension|get#call(i)<core::int>;
+  t.{self::Class::call}{<T extends core::Object? = dynamic>() → dynamic}<core::int>;
+  self::Extension|get#call(s)<core::int>;
+}
+static method test<T extends self::Class?, S extends core::int>(self::Class? c1, self::GetterCall c2, core::int? i, self::test::T% t1, self::test::T? t2, self::test::S? s, <T extends core::Object? = dynamic>() →? void f1, Never n, dynamic d, core::String a, core::double b, core::bool c, FutureOr<self::Class>f2, core::Function f3) → dynamic {
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:29:5: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Class?'.
+ - 'Class' is from 'pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart'.
+Try changing the operand or remove the type arguments.
+  c1<int>; // error
+    ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:30:5: Error: The static type of the explicit instantiation operand must be a generic function type but is 'GetterCall'.
+ - 'GetterCall' is from 'pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart'.
+Try changing the operand or remove the type arguments.
+  c2<int>; // error
+    ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:31:4: Error: The static type of the explicit instantiation operand must be a generic function type but is 'int?'.
+Try changing the operand or remove the type arguments.
+  i<int>; // error
+   ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:32:5: Error: The static type of the explicit instantiation operand must be a generic function type but is 'T'.
+Try changing the operand or remove the type arguments.
+  t1<int>; // error
+    ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:33:5: Error: The static type of the explicit instantiation operand must be a generic function type but is 'T?'.
+Try changing the operand or remove the type arguments.
+  t2<int>; // error
+    ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:34:4: Error: The static type of the explicit instantiation operand must be a generic function type but is 'S?'.
+Try changing the operand or remove the type arguments.
+  s<int>; // error
+   ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:35:5: Error: The static type of the explicit instantiation operand must be a non-null generic function type but is 'void Function<T>()?'.
+Try changing the operand or remove the type arguments.
+  f1<int>; // error
+    ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:36:4: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Never'.
+Try changing the operand or remove the type arguments.
+  n<int>; // error
+   ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:37:4: Error: The static type of the explicit instantiation operand must be a generic function type but is 'dynamic'.
+Try changing the operand or remove the type arguments.
+  d<int>; // error
+   ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:38:4: Error: The static type of the explicit instantiation operand must be a generic function type but is 'String'.
+Try changing the operand or remove the type arguments.
+  a<int>; // error
+   ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:39:4: Error: The static type of the explicit instantiation operand must be a generic function type but is 'double'.
+Try changing the operand or remove the type arguments.
+  b<int>; // error
+   ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:40:4: Error: The static type of the explicit instantiation operand must be a generic function type but is 'bool'.
+Try changing the operand or remove the type arguments.
+  c<int>; // error
+   ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:41:5: Error: The static type of the explicit instantiation operand must be a generic function type but is 'FutureOr<Class>'.
+ - 'Class' is from 'pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart'.
+Try changing the operand or remove the type arguments.
+  f2<int>; // error
+    ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/callable_instantiation.dart:42:5: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Function'.
+ - 'Function' is from 'dart:core'.
+Try changing the operand or remove the type arguments.
+  f3<int>; // error
+    ^";
+}
+static method Extension|call<T extends core::Object? = dynamic>(lowered final core::int #this) → dynamic {}
+static method Extension|get#call(lowered final core::int #this) → <T extends core::Object? = dynamic>() → dynamic
+  return <T extends core::Object? = dynamic>() → dynamic => self::Extension|call<T%>(#this);
+static method ExtensionGetter|get#call(lowered final core::double #this) → <T extends core::Object? = dynamic>() → void
+  return <T extends core::Object? = dynamic>() → void {};
+static method ExtensionSetter|set#call(lowered final core::bool #this, <T extends core::Object? = dynamic>() → void value) → void {}
+static method Ambiguous1|call<T extends core::Object? = dynamic>(lowered final core::String #this) → dynamic {}
+static method Ambiguous1|get#call(lowered final core::String #this) → <T extends core::Object? = dynamic>() → dynamic
+  return <T extends core::Object? = dynamic>() → dynamic => self::Ambiguous1|call<T%>(#this);
+static method Ambiguous2|call<T extends core::Object? = dynamic>(lowered final core::String #this) → dynamic {}
+static method Ambiguous2|get#call(lowered final core::String #this) → <T extends core::Object? = dynamic>() → dynamic
+  return <T extends core::Object? = dynamic>() → dynamic => self::Ambiguous2|call<T%>(#this);
+static method main() → dynamic {
+  self::method<self::Class, core::int>(new self::Class::•(), 0, new self::Class::•(), 0);
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/const_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/const_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..fc95e6e
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/const_tear_off.dart.weak.modular.expect
@@ -0,0 +1,68 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef B<T extends core::Object? = dynamic> = self::A<T%>;
+typedef C<unrelated T extends core::Object? = dynamic> = self::A<core::int>;
+class A<T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+  static factory fact<T extends core::Object? = dynamic>() → self::A<self::A::fact::T%>
+    return new self::A::•<self::A::fact::T%>();
+  static factory redirect<T extends core::Object? = dynamic>() → self::A<self::A::redirect::T%>
+    return new self::A::•<self::A::redirect::T%>();
+}
+static const field <T extends core::Object? = dynamic>() → self::A<T%> a = #C2;
+static const field () → self::A<core::int> b = #C3;
+static const field <T extends core::Object? = dynamic>() → self::A<T%> c = #C4;
+static const field () → self::A<core::int> d = #C5;
+static const field <T extends core::Object? = dynamic>() → self::A<T%> e = #C6;
+static const field () → self::A<core::int> f = #C7;
+static const field <T extends core::Object? = dynamic>() → self::A<T%> g = #C2;
+static const field () → self::A<core::int> h = #C3;
+static const field <T extends core::Object? = dynamic>() → self::A<T%> i = #C4;
+static const field () → self::A<core::int> j = #C5;
+static const field <T extends core::Object? = dynamic>() → self::A<T%> k = #C6;
+static const field () → self::A<core::int> l = #C7;
+static const field <unrelated T extends core::Object? = dynamic>() → self::A<core::int> m = #C8;
+static const field () → self::A<core::int> n = #C3;
+static const field <unrelated T extends core::Object? = dynamic>() → self::A<core::int> o = #C9;
+static const field () → self::A<core::int> p = #C5;
+static const field <unrelated T extends core::Object? = dynamic>() → self::A<core::int> q = #C10;
+static const field () → self::A<core::int> r = #C7;
+static method test() → dynamic {
+  <T extends core::Object? = dynamic>() → self::A<T%> a = #C2;
+  () → self::A<core::int> b = #C3;
+  <T extends core::Object? = dynamic>() → self::A<T%> c = #C4;
+  () → self::A<core::int> d = #C5;
+  <T extends core::Object? = dynamic>() → self::A<T%> e = #C6;
+  () → self::A<core::int> f = #C7;
+  <T extends core::Object? = dynamic>() → self::A<T%> g = #C2;
+  () → self::A<core::int> h = #C3;
+  <T extends core::Object? = dynamic>() → self::A<T%> i = #C4;
+  () → self::A<core::int> j = #C5;
+  <T extends core::Object? = dynamic>() → self::A<T%> k = #C6;
+  () → self::A<core::int> l = #C7;
+  <unrelated T extends core::Object? = dynamic>() → self::A<core::int> m = #C8;
+  () → self::A<core::int> n = #C3;
+  <unrelated T extends core::Object? = dynamic>() → self::A<core::int> o = #C9;
+  () → self::A<core::int> p = #C5;
+  <unrelated T extends core::Object? = dynamic>() → self::A<core::int> q = #C10;
+  () → self::A<core::int> r = #C7;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::A::redirect
+  #C2 = constructor-tearoff self::A::•
+  #C3 = instantiation #C2 <core::int*>
+  #C4 = constructor-tearoff self::A::fact
+  #C5 = instantiation #C4 <core::int*>
+  #C6 = redirecting-factory-tearoff self::A::redirect
+  #C7 = instantiation #C6 <core::int*>
+  #C8 = typedef-tearoff <unrelated T extends core::Object? = dynamic>.(#C2<core::int>)
+  #C9 = typedef-tearoff <unrelated T extends core::Object? = dynamic>.(#C4<core::int>)
+  #C10 = typedef-tearoff <unrelated T extends core::Object? = dynamic>.(#C6<core::int>)
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart.weak.modular.expect
new file mode 100644
index 0000000..25718f4
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart.weak.modular.expect
@@ -0,0 +1,321 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:13:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>;
+//            ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:13:18: Error: Expected '[' before this.
+//   Class<int><int>;
+//                  ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:14:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>();
+//            ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:14:20: Error: Unexpected token ';'.
+//   Class<int><int>();
+//                    ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:14:20: Error: Expected a function body or '=>'.
+// Try adding {}.
+//   Class<int><int>();
+//                    ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:14:20: Error: Expected ';' after this.
+//   Class<int><int>();
+//                    ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:18:14: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   Class<int>.named<int>();
+//              ^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:19:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named;
+//            ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:19:18: Error: Expected '[' before this.
+//   Class<int><int>.named;
+//                  ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:20:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named();
+//            ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:20:18: Error: Expected '[' before this.
+//   Class<int><int>.named();
+//                  ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:21:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int>;
+//            ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:21:18: Error: Expected '[' before this.
+//   Class<int><int>.named<int>;
+//                  ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:22:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int>();
+//            ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:22:18: Error: Expected '[' before this.
+//   Class<int><int>.named<int>();
+//                  ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:23:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int><int>;
+//            ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:23:18: Error: Expected '[' before this.
+//   Class<int><int>.named<int><int>;
+//                  ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:23:24: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int><int>;
+//                        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:23:28: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int><int>;
+//                            ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:23:34: Error: Expected '[' before this.
+//   Class<int><int>.named<int><int>;
+//                                  ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:24:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int><int>();
+//            ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:24:18: Error: Expected '[' before this.
+//   Class<int><int>.named<int><int>();
+//                  ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:24:24: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int><int>();
+//                        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:24:28: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int><int>();
+//                            ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:24:36: Error: Unexpected token ';'.
+//   Class<int><int>.named<int><int>();
+//                                    ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:24:36: Error: Expected a function body or '=>'.
+// Try adding {}.
+//   Class<int><int>.named<int><int>();
+//                                    ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:24:36: Error: Expected ';' after this.
+//   Class<int><int>.named<int><int>();
+//                                    ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:13:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>;
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:14:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>();
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:17:19: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Class<int> Function()'.
+//  - 'Class' is from 'pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart'.
+// Try changing the operand or remove the type arguments.
+//   Class<int>.named<int>;
+//                   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:19:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>.named;
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:19:19: Error: The getter 'named' isn't defined for the class 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'named'.
+//   Class<int><int>.named;
+//                   ^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:20:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>.named();
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:20:19: Error: The method 'named' isn't defined for the class 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Try correcting the name to the name of an existing method, or defining a method named 'named'.
+//   Class<int><int>.named();
+//                   ^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:21:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>.named<int>;
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:21:19: Error: The getter 'named' isn't defined for the class 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'named'.
+//   Class<int><int>.named<int>;
+//                   ^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:21:24: Error: The static type of the explicit instantiation operand must be a generic function type but is 'dynamic'.
+// Try changing the operand or remove the type arguments.
+//   Class<int><int>.named<int>;
+//                        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:22:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>.named<int>();
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:22:19: Error: The method 'named' isn't defined for the class 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Try correcting the name to the name of an existing method, or defining a method named 'named'.
+//   Class<int><int>.named<int>();
+//                   ^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:23:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>.named<int><int>;
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:23:19: Error: The getter 'named' isn't defined for the class 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'named'.
+//   Class<int><int>.named<int><int>;
+//                   ^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:24:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>.named<int><int>();
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:24:19: Error: The getter 'named' isn't defined for the class 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'named'.
+//   Class<int><int>.named<int><int>();
+//                   ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  constructor named() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+}
+static method test() → dynamic {
+  #C1;
+  new self::Class::•<core::int>();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:13:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>;
+       ^" in #C2{<unresolved>}.<(#C3){dynamic}.>(<core::int>[]);
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:14:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>();
+       ^" in #C2{<unresolved>}.<(#C3){dynamic}.>(<int extends core::Object? = dynamic>() → Null
+    ;
+);
+  #C5;
+  new self::Class::named<core::int>();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:17:19: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Class<int> Function()'.
+ - 'Class' is from 'pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart'.
+Try changing the operand or remove the type arguments.
+  Class<int>.named<int>;
+                  ^";
+  new self::Class::named<core::int>();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:19:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>.named;
+       ^" in #C2{<unresolved>}.<(#C3){dynamic}.>(invalid-expression "pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:19:19: Error: The getter 'named' isn't defined for the class 'List<int>'.
+ - 'List' is from 'dart:core'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'named'.
+  Class<int><int>.named;
+                  ^^^^^" in <core::int>[]{<unresolved>}.named);
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:20:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>.named();
+       ^" in #C2{<unresolved>}.<(#C3){dynamic}.>(invalid-expression "pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:20:19: Error: The method 'named' isn't defined for the class 'List<int>'.
+ - 'List' is from 'dart:core'.
+Try correcting the name to the name of an existing method, or defining a method named 'named'.
+  Class<int><int>.named();
+                  ^^^^^" in <core::int>[]{<unresolved>}.named());
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:21:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>.named<int>;
+       ^" in #C2{<unresolved>}.<(#C3){dynamic}.>(invalid-expression "pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:21:24: Error: The static type of the explicit instantiation operand must be a generic function type but is 'dynamic'.
+Try changing the operand or remove the type arguments.
+  Class<int><int>.named<int>;
+                       ^");
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:22:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>.named<int>();
+       ^" in #C2{<unresolved>}.<(#C3){dynamic}.>(invalid-expression "pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:22:19: Error: The method 'named' isn't defined for the class 'List<int>'.
+ - 'List' is from 'dart:core'.
+Try correcting the name to the name of an existing method, or defining a method named 'named'.
+  Class<int><int>.named<int>();
+                  ^^^^^" in <core::int>[]{<unresolved>}.named<core::int>());
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:23:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>.named<int><int>;
+       ^" in #C2{<unresolved>}.<(#C3){dynamic}.>(invalid-expression "pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:23:19: Error: The getter 'named' isn't defined for the class 'List<int>'.
+ - 'List' is from 'dart:core'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'named'.
+  Class<int><int>.named<int><int>;
+                  ^^^^^" in <core::int>[]{<unresolved>}.named){dynamic}.<(#C3){dynamic}.>(<core::int>[]);
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:24:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>.named<int><int>();
+       ^" in #C2{<unresolved>}.<(#C3){dynamic}.>(invalid-expression "pkg/front_end/testcases/constructor_tearoffs/duplicate_instantiation.dart:24:19: Error: The getter 'named' isn't defined for the class 'List<int>'.
+ - 'List' is from 'dart:core'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'named'.
+  Class<int><int>.named<int><int>();
+                  ^^^^^" in <core::int>[]{<unresolved>}.named){dynamic}.<(#C3){dynamic}.>(<int extends core::Object? = dynamic>() → Null
+    ;
+);
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = TypeLiteralConstant(self::Class<core::int*>*)
+  #C2 = TypeLiteralConstant(self::Class<dynamic>*)
+  #C3 = TypeLiteralConstant(core::int*)
+  #C4 = constructor-tearoff self::Class::named
+  #C5 = instantiation #C4 <core::int*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/dynamic_explicit_instantiation.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/dynamic_explicit_instantiation.dart.weak.modular.expect
new file mode 100644
index 0000000..ee9aed5
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/dynamic_explicit_instantiation.dart.weak.modular.expect
@@ -0,0 +1,47 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/dynamic_explicit_instantiation.dart:5:26: Error: The static type of the explicit instantiation operand must be a generic function type but is 'dynamic'.
+// Try changing the operand or remove the type arguments.
+// test1(dynamic x) => x.foo<int>; // Error.
+//                          ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/dynamic_explicit_instantiation.dart:6:24: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Never'.
+// Try changing the operand or remove the type arguments.
+// test2(Never x) => x.foo<int>; // Error.
+//                        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/dynamic_explicit_instantiation.dart:7:31: Error: The static type of the explicit instantiation operand must be a generic function type but is 'String Function()'.
+// Try changing the operand or remove the type arguments.
+// test3(dynamic x) => x.toString<int>; // Error.
+//                               ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/dynamic_explicit_instantiation.dart:8:29: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Never'.
+// Try changing the operand or remove the type arguments.
+// test4(Never x) => x.toString<int>; // Error.
+//                             ^
+//
+import self as self;
+
+static method test1(dynamic x) → dynamic
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/dynamic_explicit_instantiation.dart:5:26: Error: The static type of the explicit instantiation operand must be a generic function type but is 'dynamic'.
+Try changing the operand or remove the type arguments.
+test1(dynamic x) => x.foo<int>; // Error.
+                         ^";
+static method test2(Never x) → dynamic
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/dynamic_explicit_instantiation.dart:6:24: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Never'.
+Try changing the operand or remove the type arguments.
+test2(Never x) => x.foo<int>; // Error.
+                       ^";
+static method test3(dynamic x) → dynamic
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/dynamic_explicit_instantiation.dart:7:31: Error: The static type of the explicit instantiation operand must be a generic function type but is 'String Function()'.
+Try changing the operand or remove the type arguments.
+test3(dynamic x) => x.toString<int>; // Error.
+                              ^";
+static method test4(Never x) → dynamic
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/dynamic_explicit_instantiation.dart:8:29: Error: The static type of the explicit instantiation operand must be a generic function type but is 'Never'.
+Try changing the operand or remove the type arguments.
+test4(Never x) => x.toString<int>; // Error.
+                            ^";
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation.dart.weak.modular.expect
new file mode 100644
index 0000000..63427ae
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation.dart.weak.modular.expect
@@ -0,0 +1,103 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef ListList<T extends core::Object? = dynamic> = core::List<core::List<T%>>;
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  static method stat<T extends core::Object? = dynamic>(self::C::stat::T% value) → self::C::stat::T%
+    return value;
+  method inst<T extends core::Object? = dynamic>(self::C::inst::T% value) → self::C::inst::T%
+    return value;
+  method method() → void {
+    (core::int) → core::int f1 = #C2;
+    core::String f1TypeName = #C2.{core::Object::runtimeType}{core::Type}.{core::Type::toString}(){() → core::String};
+    (core::int) → core::int f2 = this.{self::C::inst}{<T extends core::Object? = dynamic>(T%) → T%}<core::int>;
+    core::String f2TypeName = (this.{self::C::inst}{<T extends core::Object? = dynamic>(T%) → T%}<core::int>).{core::Object::runtimeType}{core::Type}.{core::Type::toString}(){() → core::String};
+    (core::int) → core::int f3 = this.{self::C::inst}{<T extends core::Object? = dynamic>(T%) → T%}<core::int>;
+    core::String f3TypeName = (this.{self::C::inst}{<T extends core::Object? = dynamic>(T%) → T%}<core::int>).{core::Object::runtimeType}{core::Type}.{core::Type::toString}(){() → core::String};
+  }
+}
+abstract class M extends self::C /*isMixinDeclaration*/  {
+  static method mstat<T extends core::Object? = dynamic>(self::M::mstat::T% value) → self::M::mstat::T%
+    return value;
+  method minst<T extends core::Object? = dynamic>(self::M::minst::T% value) → self::M::minst::T%
+    return value;
+  method mmethod() → void {
+    (core::int) → core::int f1 = #C4;
+    core::String f1TypeName = #C4.{core::Object::runtimeType}{core::Type}.{core::Type::toString}(){() → core::String};
+    (core::int) → core::int f2 = this.{self::M::minst}{<T extends core::Object? = dynamic>(T%) → T%}<core::int>;
+    core::String f2TypeName = (this.{self::M::minst}{<T extends core::Object? = dynamic>(T%) → T%}<core::int>).{core::Object::runtimeType}{core::Type}.{core::Type::toString}(){() → core::String};
+    (core::int) → core::int f3 = this.{self::M::minst}{<T extends core::Object? = dynamic>(T%) → T%}<core::int>;
+    core::String f3TypeName = (this.{self::M::minst}{<T extends core::Object? = dynamic>(T%) → T%}<core::int>).{core::Object::runtimeType}{core::Type}.{core::Type::toString}(){() → core::String};
+  }
+}
+abstract class _D&C&M = self::C with self::M /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_D&C&M
+    : super self::C::•()
+    ;
+  mixin-super-stub method minst<T extends core::Object? = dynamic>(self::_D&C&M::minst::T% value) → self::_D&C&M::minst::T%
+    return super.{self::M::minst}<self::_D&C&M::minst::T%>(value);
+  mixin-super-stub method mmethod() → void
+    return super.{self::M::mmethod}();
+}
+class D extends self::_D&C&M {
+  synthetic constructor •() → self::D
+    : super self::_D&C&M::•()
+    ;
+  method method() → void {
+    (core::int) → core::int f4 = super.{self::C::inst}<core::int>;
+    core::String f4TypeName = (super.{self::C::inst}<core::int>).{core::Object::runtimeType}{core::Type}.{core::Type::toString}(){() → core::String};
+  }
+}
+extension Ext on self::C {
+  static method estat = self::Ext|estat;
+  method einst = self::Ext|einst;
+  tearoff einst = self::Ext|get#einst;
+  method emethod = self::Ext|emethod;
+  tearoff emethod = self::Ext|get#emethod;
+}
+static method top<T extends core::Object? = dynamic>(self::top::T% value) → self::top::T%
+  return value;
+static method Ext|estat<T extends core::Object? = dynamic>(self::Ext|estat::T% value) → self::Ext|estat::T%
+  return value;
+static method Ext|einst<T extends core::Object? = dynamic>(lowered final self::C #this, self::Ext|einst::T% value) → self::Ext|einst::T%
+  return value;
+static method Ext|get#einst(lowered final self::C #this) → <T extends core::Object? = dynamic>(T%) → T%
+  return <T extends core::Object? = dynamic>(T% value) → T% => self::Ext|einst<T%>(#this, value);
+static method Ext|emethod(lowered final self::C #this) → void {
+  (core::int) → core::int f1 = #C6;
+  core::String f1TypeName = #C6.{core::Object::runtimeType}{core::Type}.{core::Type::toString}(){() → core::String};
+  (core::int) → core::int f2 = self::Ext|get#einst(#this)<core::int>;
+  core::String f2TypeName = (self::Ext|get#einst(#this)<core::int>).{core::Object::runtimeType}{core::Type}.{core::Type::toString}(){() → core::String};
+  (core::int) → core::int f3 = self::Ext|get#einst(#this)<core::int>;
+  core::String f3TypeName = (self::Ext|get#einst(#this)<core::int>).{core::Object::runtimeType}{core::Type}.{core::Type::toString}(){() → core::String};
+}
+static method Ext|get#emethod(lowered final self::C #this) → () → void
+  return () → void => self::Ext|emethod(#this);
+static method main() → void {
+  core::Type t1 = #C7;
+  core::Type t2 = #C8;
+  function local<T extends core::Object? = dynamic>(T% value) → T%
+    return value;
+  (core::int) → core::int f3 = local<core::int>;
+  self::D d = new self::D::•();
+  (core::int) → core::int f4 = d.{self::C::inst}{<T extends core::Object? = dynamic>(T%) → T%}<core::int>;
+  (core::int) → core::int f5 = d.{self::_D&C&M::minst}{<T extends core::Object? = dynamic>(T%) → T%}<core::int>;
+  (core::int) → core::int f6 = self::Ext|get#einst(d)<core::int>;
+  core::String typeName = #C7.{core::Type::toString}(){() → core::String};
+  core::String functionTypeName = (local<core::int>).{core::Object::runtimeType}{core::Type}.{core::Type::toString}(){() → core::String};
+}
+
+constants  {
+  #C1 = static-tearoff self::C::stat
+  #C2 = instantiation #C1 <core::int*>
+  #C3 = static-tearoff self::M::mstat
+  #C4 = instantiation #C3 <core::int*>
+  #C5 = static-tearoff self::Ext|estat
+  #C6 = instantiation #C5 <core::int*>
+  #C7 = TypeLiteralConstant(core::List<core::int*>*)
+  #C8 = TypeLiteralConstant(core::List<core::List<core::int*>*>*)
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart.weak.modular.expect
new file mode 100644
index 0000000..8ed55ac
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart.weak.modular.expect
@@ -0,0 +1,112 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:15:13: Error: Too many type arguments: 1 allowed, but 2 found.
+// Try removing the extra type arguments.
+//   var d = id<int, String>; // error - too many args
+//             ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:16:17: Error: Too few type arguments: 2 required, 1 given.
+// Try adding the missing type arguments.
+//   var e = method<int>; // error - too few args
+//                 ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:17:12: Error: The static type of the explicit instantiation operand must be a generic function type but is 'int'.
+// Try changing the operand or remove the type arguments.
+//   var f = 0<int>; // error - non-function type operand
+//            ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:18:15: Error: The static type of the explicit instantiation operand must be a generic function type but is 'dynamic Function()'.
+// Try changing the operand or remove the type arguments.
+//   var g = main<int>; // error - non-generic function type operand
+//               ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:19:24: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'X Function<X extends num>(X)'.
+// Try changing type arguments so that they conform to the bounds.
+//   var h = boundedMethod<String>; // error - invalid bound
+//                        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:25:11: Error: Too many type arguments: 1 allowed, but 2 found.
+// Try removing the extra type arguments.
+// var d = id<int, String>; // error - too many args
+//           ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:26:15: Error: Too few type arguments: 2 required, 1 given.
+// Try adding the missing type arguments.
+// var e = method<int>; // error - too few args
+//               ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:27:10: Error: The static type of the explicit instantiation operand must be a generic function type but is 'int'.
+// Try changing the operand or remove the type arguments.
+// var f = 0<int>; // error - non-function type operand
+//          ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:28:13: Error: The static type of the explicit instantiation operand must be a generic function type but is 'dynamic Function()'.
+// Try changing the operand or remove the type arguments.
+// var g = main<int>; // error - non-generic function type operand
+//             ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:29:22: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'X Function<X extends num>(X)'.
+// Try changing type arguments so that they conform to the bounds.
+// var h = boundedMethod<String>; // error - invalid bound
+//                      ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field <X extends core::Object? = dynamic>(X%) → X% a = #C1;
+static field (core::int) → core::int b = self::a<core::int>;
+static field (core::int) → core::int c = #C2;
+static field invalid-type d = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:25:11: Error: Too many type arguments: 1 allowed, but 2 found.
+Try removing the extra type arguments.
+var d = id<int, String>; // error - too many args
+          ^";
+static field invalid-type e = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:26:15: Error: Too few type arguments: 2 required, 1 given.
+Try adding the missing type arguments.
+var e = method<int>; // error - too few args
+              ^";
+static field invalid-type f = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:27:10: Error: The static type of the explicit instantiation operand must be a generic function type but is 'int'.
+Try changing the operand or remove the type arguments.
+var f = 0<int>; // error - non-function type operand
+         ^";
+static field invalid-type g = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:28:13: Error: The static type of the explicit instantiation operand must be a generic function type but is 'dynamic Function()'.
+Try changing the operand or remove the type arguments.
+var g = main<int>; // error - non-generic function type operand
+            ^";
+static field (core::String) → core::String h = #C4;
+static method id<X extends core::Object? = dynamic>(self::id::X% x) → self::id::X%
+  return x;
+static method method<X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → void {}
+static method boundedMethod<X extends core::num>(self::boundedMethod::X x) → self::boundedMethod::X
+  return x;
+static method test() → dynamic {
+  <X extends core::Object? = dynamic>(X%) → X% a = #C1;
+  (core::int) → core::int b = a<core::int>;
+  (core::int) → core::int c = #C2;
+  invalid-type d = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:15:13: Error: Too many type arguments: 1 allowed, but 2 found.
+Try removing the extra type arguments.
+  var d = id<int, String>; // error - too many args
+            ^";
+  invalid-type e = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:16:17: Error: Too few type arguments: 2 required, 1 given.
+Try adding the missing type arguments.
+  var e = method<int>; // error - too few args
+                ^";
+  invalid-type f = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:17:12: Error: The static type of the explicit instantiation operand must be a generic function type but is 'int'.
+Try changing the operand or remove the type arguments.
+  var f = 0<int>; // error - non-function type operand
+           ^";
+  invalid-type g = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/explicit_instantiation_errors.dart:18:15: Error: The static type of the explicit instantiation operand must be a generic function type but is 'dynamic Function()'.
+Try changing the operand or remove the type arguments.
+  var g = main<int>; // error - non-generic function type operand
+              ^";
+  (core::String) → core::String h = #C4;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::id
+  #C2 = instantiation #C1 <core::int*>
+  #C3 = static-tearoff self::boundedMethod
+  #C4 = instantiation #C3 <core::String*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/explicit_new_as_unnamed.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/explicit_new_as_unnamed.dart.weak.modular.expect
new file mode 100644
index 0000000..13d3f0b
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/explicit_new_as_unnamed.dart.weak.modular.expect
@@ -0,0 +1,105 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_new_as_unnamed.dart:15:3: Error: 'C' is already declared in this scope.
+//   C.new(); // Error.
+//   ^
+// pkg/front_end/testcases/constructor_tearoffs/explicit_new_as_unnamed.dart:14:3: Context: Previous declaration of 'C'.
+//   C();
+//   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_new_as_unnamed.dart:20:3: Error: 'D' is already declared in this scope.
+//   D(); // Error.
+//   ^
+// pkg/front_end/testcases/constructor_tearoffs/explicit_new_as_unnamed.dart:19:3: Context: Previous declaration of 'D'.
+//   D.new();
+//   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_new_as_unnamed.dart:26:11: Error: 'E1' is already declared in this scope.
+//   factory E1.new() => E1._(); // Error.
+//           ^^
+// pkg/front_end/testcases/constructor_tearoffs/explicit_new_as_unnamed.dart:25:3: Context: Previous declaration of 'E1'.
+//   E1();
+//   ^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_new_as_unnamed.dart:32:3: Error: 'E2' is already declared in this scope.
+//   E2();
+//   ^^
+// pkg/front_end/testcases/constructor_tearoffs/explicit_new_as_unnamed.dart:31:11: Context: Previous declaration of 'E2'.
+//   factory E2.new() => E2._(); // Error.
+//           ^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_new_as_unnamed.dart:38:11: Error: 'E3' is already declared in this scope.
+//   factory E3.new() = E3._; // Error.
+//           ^^
+// pkg/front_end/testcases/constructor_tearoffs/explicit_new_as_unnamed.dart:37:3: Context: Previous declaration of 'E3'.
+//   E3();
+//   ^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/explicit_new_as_unnamed.dart:44:3: Error: 'E4' is already declared in this scope.
+//   E4(); // Error.
+//   ^^
+// pkg/front_end/testcases/constructor_tearoffs/explicit_new_as_unnamed.dart:43:11: Context: Previous declaration of 'E4'.
+//   factory E4.new() = E4._;
+//           ^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class B extends core::Object {
+  constructor •() → self::B
+    : super core::Object::•()
+    ;
+}
+class C extends core::Object {
+  constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+class D extends core::Object {
+  constructor •() → self::D
+    : super core::Object::•()
+    ;
+}
+class E1 extends core::Object {
+  constructor _() → self::E1
+    : super core::Object::•()
+    ;
+  constructor •() → self::E1
+    : super core::Object::•()
+    ;
+}
+class E2 extends core::Object {
+  constructor _() → self::E2
+    : super core::Object::•()
+    ;
+  static factory •() → self::E2
+    return new self::E2::_();
+}
+class E3 extends core::Object {
+  constructor _() → self::E3
+    : super core::Object::•()
+    ;
+  constructor •() → self::E3
+    : super core::Object::•()
+    ;
+}
+class E4 extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor _() → self::E4
+    : super core::Object::•()
+    ;
+  static factory •() → self::E4
+    return new self::E4::_();
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::E4::•
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart.weak.modular.expect
new file mode 100644
index 0000000..d91a515
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart.weak.modular.expect
@@ -0,0 +1,140 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:13:32: Error: A value of type 'A<X/*1*/> Function<X>(X/*1*/, int)' can't be returned from a function with return type 'A<X/*2*/> Function<X>(X/*2*/)'.
+//  - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart'.
+//  - 'X/*1*/' is from 'unknown'.
+//  - 'X/*2*/' is from 'unknown'.
+// A<X> Function<X>(X) test2() => A.foo2; // Error.
+//                                ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:14:32: Error: A value of type 'A<X/*1*/> Function<X>()' can't be returned from a function with return type 'A<X/*2*/> Function<X>(X/*2*/)'.
+//  - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart'.
+//  - 'X/*1*/' is from 'unknown'.
+//  - 'X/*2*/' is from 'unknown'.
+// A<X> Function<X>(X) test3() => A.new; // Error.
+//                                ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:15:32: Error: A value of type 'A<int> Function()' can't be returned from a function with return type 'A<X> Function<X>(X)'.
+//  - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart'.
+// A<X> Function<X>(X) test4() => A<int>.new; // Error.
+//                                ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:16:32: Error: Too many type arguments: 1 allowed, but 2 found.
+// Try removing the extra type arguments.
+// A<X> Function<X>(X) test5() => A<int, String>.new; // Error.
+//                                ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:17:32: Error: A value of type 'A<int> Function(int)' can't be returned from a function with return type 'A<X> Function<X>(X)'.
+//  - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart'.
+// A<X> Function<X>(X) test6() => A<int>.foo1; // Error.
+//                                ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:18:32: Error: Too many type arguments: 1 allowed, but 2 found.
+// Try removing the extra type arguments.
+// A<X> Function<X>(X) test7() => A<int, String>.foo1; // Error.
+//                                ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:19:32: Error: A value of type 'A<int> Function(int, int)' can't be returned from a function with return type 'A<X> Function<X>(X)'.
+//  - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart'.
+// A<X> Function<X>(X) test8() => A<int>.foo2; // Error.
+//                                ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:20:32: Error: Too many type arguments: 1 allowed, but 2 found.
+// Try removing the extra type arguments.
+// A<X> Function<X>(X) test9() => A<int, String>.foo2; // Error.
+//                                ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:22:33: Error: A value of type 'A<X/*1*/> Function<X>()' can't be returned from a function with return type 'A<X/*2*/> Function<X>(X/*2*/)'.
+//  - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart'.
+//  - 'X/*1*/' is from 'unknown'.
+//  - 'X/*2*/' is from 'unknown'.
+// A<X> Function<X>(X) test11() => A.bar1; // Error.
+//                                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object? = dynamic> extends core::Object {
+  constructor foo1(self::A::X% x) → self::A<self::A::X%>
+    : super core::Object::•() {}
+  constructor foo2(self::A::X% x, core::int y) → self::A<self::A::X%>
+    : super core::Object::•() {}
+  constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+  static factory bar1<X extends core::Object? = dynamic>() → self::A<self::A::bar1::X%>
+    return new self::A::•<self::A::bar1::X%>();
+}
+static method test1() → <X extends core::Object? = dynamic>(X%) → self::A<X%>
+  return #C1;
+static method test2() → <X extends core::Object? = dynamic>(X%) → self::A<X%>
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:13:32: Error: A value of type 'A<X/*1*/> Function<X>(X/*1*/, int)' can't be returned from a function with return type 'A<X/*2*/> Function<X>(X/*2*/)'.
+ - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart'.
+ - 'X/*1*/' is from 'unknown'.
+ - 'X/*2*/' is from 'unknown'.
+A<X> Function<X>(X) test2() => A.foo2; // Error.
+                               ^" in #C2 as{TypeError,ForNonNullableByDefault} Never;
+static method test3() → <X extends core::Object? = dynamic>(X%) → self::A<X%>
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:14:32: Error: A value of type 'A<X/*1*/> Function<X>()' can't be returned from a function with return type 'A<X/*2*/> Function<X>(X/*2*/)'.
+ - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart'.
+ - 'X/*1*/' is from 'unknown'.
+ - 'X/*2*/' is from 'unknown'.
+A<X> Function<X>(X) test3() => A.new; // Error.
+                               ^" in #C3 as{TypeError,ForNonNullableByDefault} Never;
+static method test4() → <X extends core::Object? = dynamic>(X%) → self::A<X%>
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:15:32: Error: A value of type 'A<int> Function()' can't be returned from a function with return type 'A<X> Function<X>(X)'.
+ - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart'.
+A<X> Function<X>(X) test4() => A<int>.new; // Error.
+                               ^" in #C4 as{TypeError,ForNonNullableByDefault} Never;
+static method test5() → <X extends core::Object? = dynamic>(X%) → self::A<X%>
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:16:32: Error: Too many type arguments: 1 allowed, but 2 found.
+Try removing the extra type arguments.
+A<X> Function<X>(X) test5() => A<int, String>.new; // Error.
+                               ^";
+static method test6() → <X extends core::Object? = dynamic>(X%) → self::A<X%>
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:17:32: Error: A value of type 'A<int> Function(int)' can't be returned from a function with return type 'A<X> Function<X>(X)'.
+ - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart'.
+A<X> Function<X>(X) test6() => A<int>.foo1; // Error.
+                               ^" in #C5 as{TypeError,ForNonNullableByDefault} Never;
+static method test7() → <X extends core::Object? = dynamic>(X%) → self::A<X%>
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:18:32: Error: Too many type arguments: 1 allowed, but 2 found.
+Try removing the extra type arguments.
+A<X> Function<X>(X) test7() => A<int, String>.foo1; // Error.
+                               ^";
+static method test8() → <X extends core::Object? = dynamic>(X%) → self::A<X%>
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:19:32: Error: A value of type 'A<int> Function(int, int)' can't be returned from a function with return type 'A<X> Function<X>(X)'.
+ - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart'.
+A<X> Function<X>(X) test8() => A<int>.foo2; // Error.
+                               ^" in #C6 as{TypeError,ForNonNullableByDefault} Never;
+static method test9() → <X extends core::Object? = dynamic>(X%) → self::A<X%>
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:20:32: Error: Too many type arguments: 1 allowed, but 2 found.
+Try removing the extra type arguments.
+A<X> Function<X>(X) test9() => A<int, String>.foo2; // Error.
+                               ^";
+static method test10() → <X extends core::Object? = dynamic>() → self::A<X%>
+  return #C7;
+static method test11() → <X extends core::Object? = dynamic>(X%) → self::A<X%>
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart:22:33: Error: A value of type 'A<X/*1*/> Function<X>()' can't be returned from a function with return type 'A<X/*2*/> Function<X>(X/*2*/)'.
+ - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_with_context.dart'.
+ - 'X/*1*/' is from 'unknown'.
+ - 'X/*2*/' is from 'unknown'.
+A<X> Function<X>(X) test11() => A.bar1; // Error.
+                                ^" in #C7 as{TypeError,ForNonNullableByDefault} Never;
+static method test12() → () → self::A<core::int>
+  return #C8;
+static method test13() → () → self::A<core::int>
+  return #C8;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::A::foo1
+  #C2 = constructor-tearoff self::A::foo2
+  #C3 = constructor-tearoff self::A::•
+  #C4 = instantiation #C3 <core::int*>
+  #C5 = instantiation #C1 <core::int*>
+  #C6 = instantiation #C2 <core::int*>
+  #C7 = constructor-tearoff self::A::bar1
+  #C8 = instantiation #C7 <core::int*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_without_context.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_without_context.dart.weak.modular.expect
new file mode 100644
index 0000000..a5cdb82
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_without_context.dart.weak.modular.expect
@@ -0,0 +1,102 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_without_context.dart:18:23: Error: Too many type arguments: 1 allowed, but 2 found.
+// Try removing the extra type arguments.
+// testFooExtraArgs() => A<int, String>.foo; // Error.
+//                       ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_without_context.dart:19:23: Error: Too many type arguments: 1 allowed, but 2 found.
+// Try removing the extra type arguments.
+// testNewExtraArgs() => A<int, String>.new; // Error.
+//                       ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_without_context.dart:20:23: Error: Too many type arguments: 1 allowed, but 2 found.
+// Try removing the extra type arguments.
+// testBarExtraArgs() => A<int, String>.bar; // Error.
+//                       ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_without_context.dart:30:22: Error: Too many type arguments: 1 allowed, but 2 found.
+// Try removing the extra type arguments.
+//   var fooExtraArgs = A<int, String>.foo; // Error.
+//                      ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_without_context.dart:31:22: Error: Too many type arguments: 1 allowed, but 2 found.
+// Try removing the extra type arguments.
+//   var newExtraArgs = A<int, String>.new; // Error.
+//                      ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_without_context.dart:32:22: Error: Too many type arguments: 1 allowed, but 2 found.
+// Try removing the extra type arguments.
+//   var barExtraArgs = A<int, String>.bar; // Error.
+//                      ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object? = dynamic> extends core::Object {
+  constructor foo() → self::A<self::A::X%>
+    : super core::Object::•() {}
+  constructor •() → self::A<self::A::X%>
+    : super core::Object::•() {}
+  static factory bar<X extends core::Object? = dynamic>() → self::A<self::A::bar::X%>
+    return new self::A::•<self::A::bar::X%>();
+}
+static method testFoo() → dynamic
+  return #C1;
+static method testFooArgs() → dynamic
+  return #C2;
+static method testNew() → dynamic
+  return #C3;
+static method testNewArgs() → dynamic
+  return #C4;
+static method testBar() → dynamic
+  return #C5;
+static method testBarArgs() → dynamic
+  return #C6;
+static method testFooExtraArgs() → dynamic
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_without_context.dart:18:23: Error: Too many type arguments: 1 allowed, but 2 found.
+Try removing the extra type arguments.
+testFooExtraArgs() => A<int, String>.foo; // Error.
+                      ^";
+static method testNewExtraArgs() → dynamic
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_without_context.dart:19:23: Error: Too many type arguments: 1 allowed, but 2 found.
+Try removing the extra type arguments.
+testNewExtraArgs() => A<int, String>.new; // Error.
+                      ^";
+static method testBarExtraArgs() → dynamic
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_without_context.dart:20:23: Error: Too many type arguments: 1 allowed, but 2 found.
+Try removing the extra type arguments.
+testBarExtraArgs() => A<int, String>.bar; // Error.
+                      ^";
+static method method() → dynamic {
+  <X extends core::Object? = dynamic>() → self::A<X%> foo = #C1;
+  () → self::A<core::int> fooArgs = #C2;
+  <X extends core::Object? = dynamic>() → self::A<X%> _new = #C3;
+  () → self::A<core::int> newArgs = #C4;
+  <X extends core::Object? = dynamic>() → self::A<X%> bar = #C5;
+  () → self::A<core::int> barArgs = #C6;
+  invalid-type fooExtraArgs = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_without_context.dart:30:22: Error: Too many type arguments: 1 allowed, but 2 found.
+Try removing the extra type arguments.
+  var fooExtraArgs = A<int, String>.foo; // Error.
+                     ^";
+  invalid-type newExtraArgs = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_without_context.dart:31:22: Error: Too many type arguments: 1 allowed, but 2 found.
+Try removing the extra type arguments.
+  var newExtraArgs = A<int, String>.new; // Error.
+                     ^";
+  invalid-type barExtraArgs = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/generic_tearoff_without_context.dart:32:22: Error: Too many type arguments: 1 allowed, but 2 found.
+Try removing the extra type arguments.
+  var barExtraArgs = A<int, String>.bar; // Error.
+                     ^";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::A::foo
+  #C2 = instantiation #C1 <core::int*>
+  #C3 = constructor-tearoff self::A::•
+  #C4 = instantiation #C3 <core::int*>
+  #C5 = constructor-tearoff self::A::bar
+  #C6 = instantiation #C5 <core::int*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/identical_instantiated_function_tearoffs.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/identical_instantiated_function_tearoffs.dart.weak.modular.expect
new file mode 100644
index 0000000..5abed3e
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/identical_instantiated_function_tearoffs.dart.weak.modular.expect
@@ -0,0 +1,52 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static field (core::int) → core::int implicitInstantiation = #C2;
+static field (core::int) → core::int explicitInstantiation = #C2;
+static const field (core::int) → core::int implicitConstInstantiation = #C2;
+static const field (core::int) → core::int explicitConstInstantiation = #C2;
+static method id<T extends core::Object? = dynamic>(self::id::T% t) → self::id::T%
+  return t;
+static method create<T extends core::Object? = dynamic>() → (self::create::T%) → self::create::T%
+  return #C1<self::create::T%>;
+static method main() → dynamic {
+  self::expect(true, core::identical(self::implicitInstantiation, self::implicitInstantiation));
+  self::expect(true, core::identical(self::implicitInstantiation, self::explicitInstantiation));
+  self::expect(true, core::identical(self::implicitInstantiation, #C2));
+  self::expect(true, core::identical(self::implicitInstantiation, #C2));
+  self::expect(true, core::identical(self::implicitInstantiation, #C2));
+  self::expect(false, core::identical(self::implicitInstantiation, #C3));
+  self::expect(false, core::identical(self::implicitInstantiation, self::create<core::int>()));
+  self::expect(true, core::identical(self::explicitInstantiation, self::implicitInstantiation));
+  self::expect(true, core::identical(self::explicitInstantiation, self::explicitInstantiation));
+  self::expect(true, core::identical(self::explicitInstantiation, #C2));
+  self::expect(true, core::identical(self::explicitInstantiation, #C2));
+  self::expect(true, core::identical(self::explicitInstantiation, #C2));
+  self::expect(false, core::identical(self::explicitInstantiation, #C3));
+  self::expect(false, core::identical(self::explicitInstantiation, self::create<core::int>()));
+  self::expect(true, core::identical(#C2, self::implicitInstantiation));
+  self::expect(true, core::identical(#C2, self::explicitInstantiation));
+  self::expect(true, core::identical(#C2, #C2));
+  self::expect(true, core::identical(#C2, #C2));
+  self::expect(true, core::identical(#C2, #C2));
+  self::expect(false, core::identical(#C2, #C3));
+  self::expect(false, core::identical(#C2, self::create<core::int>()));
+  self::expect(true, core::identical(#C2, self::implicitInstantiation));
+  self::expect(true, core::identical(#C2, self::explicitInstantiation));
+  self::expect(true, core::identical(#C2, #C2));
+  self::expect(true, core::identical(#C2, #C2));
+  self::expect(true, core::identical(#C2, #C2));
+  self::expect(false, core::identical(#C2, #C3));
+  self::expect(false, core::identical(#C2, self::create<core::int>()));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = static-tearoff self::id
+  #C2 = instantiation #C1 <core::int*>
+  #C3 = instantiation #C1 <core::String*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation.dart.weak.modular.expect
new file mode 100644
index 0000000..a39c27d
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  method call<T extends core::Object? = dynamic>(self::Class::call::T% t) → self::Class::call::T%
+    return t;
+}
+static field <T extends core::Object? = dynamic>(T%) → T% alias = #C1;
+static method id<T extends core::Object? = dynamic>(self::id::T% t) → self::id::T%
+  return t;
+static method method((core::int) → core::int f) → dynamic {}
+static method test() → dynamic {
+  self::Class c = new self::Class::•();
+  (core::int) → core::int f = self::alias<core::int>;
+  (core::int) → core::int g;
+  g = self::alias<core::int>;
+  (core::int) → core::int h = (let final self::Class #t1 = c in #t1 == null ?{<T extends core::Object? = dynamic>(T%) → T%} null : #t1.{self::Class::call}{<T extends core::Object? = dynamic>(T%) → T%})<core::int>;
+  g = (let final self::Class #t2 = c in #t2 == null ?{<T extends core::Object? = dynamic>(T%) → T%} null : #t2.{self::Class::call}{<T extends core::Object? = dynamic>(T%) → T%})<core::int>;
+  self::method(self::alias<core::int>);
+}
+static method main() → dynamic {
+  self::test();
+}
+
+constants  {
+  #C1 = static-tearoff self::id
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart.weak.modular.expect
new file mode 100644
index 0000000..473f61e
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart:16:30: Error: A value of type 'int Function(int, int)?' can't be assigned to a variable of type 'int Function(int, int)' because 'int Function(int, int)?' is nullable and 'int Function(int, int)' isn't.
+//   int Function(int, int) f = alias;
+//                              ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart:18:7: Error: A value of type 'int Function(int, int)?' can't be assigned to a variable of type 'int Function(int, int?)?' because 'int?' is nullable and 'int' isn't.
+//   g = alias;
+//       ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart:19:27: Error: A value of type 'int Function(int, int)' can't be assigned to a variable of type 'int Function(int, int?)' because 'int?' is nullable and 'int' isn't.
+//   int Function(int, int?) h = c;
+//                           ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart:20:3: Error: A value of type 'int Function(int, int)' can't be assigned to a variable of type 'int Function(int, int?)?' because 'int?' is nullable and 'int' isn't.
+//   g = c;
+//   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart:21:10: Error: The argument type 'int Function(int, int)?' can't be assigned to the parameter type 'int Function(int, int?)' because 'int?' is nullable and 'int' isn't.
+//   method(alias);
+//          ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  method call<T extends core::Object? = dynamic>(self::Class::call::T% t, core::int i) → self::Class::call::T%
+    return t;
+}
+static field <T extends core::Object? = dynamic>(T%, core::int) →? T% alias = #C1;
+static method id<T extends core::Object? = dynamic>(self::id::T% t, core::int i) → self::id::T%
+  return t;
+static method method((core::int, core::int?) → core::int f) → dynamic {}
+static method test() → dynamic {
+  self::Class c = new self::Class::•();
+  (core::int, core::int) → core::int f = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart:16:30: Error: A value of type 'int Function(int, int)?' can't be assigned to a variable of type 'int Function(int, int)' because 'int Function(int, int)?' is nullable and 'int Function(int, int)' isn't.
+  int Function(int, int) f = alias;
+                             ^" in (self::alias<core::int>) as{TypeError,ForNonNullableByDefault} (core::int, core::int) → core::int;
+  (core::int, core::int?) →? core::int g;
+  g = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart:18:7: Error: A value of type 'int Function(int, int)?' can't be assigned to a variable of type 'int Function(int, int?)?' because 'int?' is nullable and 'int' isn't.
+  g = alias;
+      ^" in (self::alias<core::int>) as{TypeError,ForNonNullableByDefault} (core::int, core::int?) →? core::int;
+  (core::int, core::int?) → core::int h = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart:19:27: Error: A value of type 'int Function(int, int)' can't be assigned to a variable of type 'int Function(int, int?)' because 'int?' is nullable and 'int' isn't.
+  int Function(int, int?) h = c;
+                          ^" in ((let final self::Class #t1 = c in #t1 == null ?{<T extends core::Object? = dynamic>(T%, core::int) → T%} null : #t1.{self::Class::call}{<T extends core::Object? = dynamic>(T%, core::int) → T%})<core::int>) as{TypeError,ForNonNullableByDefault} (core::int, core::int?) → core::int;
+  g = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart:20:3: Error: A value of type 'int Function(int, int)' can't be assigned to a variable of type 'int Function(int, int?)?' because 'int?' is nullable and 'int' isn't.
+  g = c;
+  ^" in ((let final self::Class #t2 = c in #t2 == null ?{<T extends core::Object? = dynamic>(T%, core::int) → T%} null : #t2.{self::Class::call}{<T extends core::Object? = dynamic>(T%, core::int) → T%})<core::int>) as{TypeError,ForNonNullableByDefault} (core::int, core::int?) →? core::int;
+  self::method(invalid-expression "pkg/front_end/testcases/constructor_tearoffs/implicit_instantiation_errors.dart:21:10: Error: The argument type 'int Function(int, int)?' can't be assigned to the parameter type 'int Function(int, int?)' because 'int?' is nullable and 'int' isn't.
+  method(alias);
+         ^" in (self::alias<core::int>) as{TypeError,ForNonNullableByDefault} (core::int, core::int?) → core::int);
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::id
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/inferred_constructor_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/inferred_constructor_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..5857e8c
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/inferred_constructor_tear_off.dart.weak.modular.expect
@@ -0,0 +1,93 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/inferred_constructor_tear_off.dart:38:9: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//     f1a(''); // error
+//         ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/inferred_constructor_tear_off.dart:52:9: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//     f2a(''); // error
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  field core::int field;
+  constructor •(core::int field) → self::Class1
+    : self::Class1::field = field, super core::Object::•()
+    ;
+}
+abstract class Interface2 extends core::Object {
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+  abstract get field() → core::int;
+}
+class Class2 extends core::Object implements self::Interface2 {
+  final field core::int field;
+  constructor •(core::int field) → self::Class2
+    : self::Class2::field = field, super core::Object::•()
+    ;
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static field (core::int) → self::Class1 Class1_new = #C1;
+static field (core::int) → self::Class2 Class2_new = #C2;
+static method main() → dynamic {
+  core::print("inSoundMode: ${self::inSoundMode}");
+  self::testInferred();
+}
+static method testInferred() → dynamic {
+  (core::int) → self::Class1 f1a = #C1;
+  self::expect(true, f1a is{ForNonNullableByDefault} (core::int) → self::Class1);
+  self::expect(false, f1a is{ForNonNullableByDefault} (core::String) → self::Class1);
+  self::Class1 c1a = f1a(0){(core::int) → self::Class1};
+  self::expect(true, c1a is{ForNonNullableByDefault} self::Class1);
+  () → Null {
+    f1a(invalid-expression "pkg/front_end/testcases/constructor_tearoffs/inferred_constructor_tear_off.dart:38:9: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+    f1a(''); // error
+        ^" in "" as{TypeError,ForNonNullableByDefault} core::int){(core::int) → self::Class1};
+  };
+  dynamic f1b = #C1;
+  dynamic c1b = f1b{dynamic}.call(0);
+  self::expect(true, c1b is{ForNonNullableByDefault} self::Class1);
+  self::throws(() → dynamic => f1b{dynamic}.call(""));
+  (core::int) → self::Class2 f2a = #C2;
+  self::expect(true, f2a is{ForNonNullableByDefault} (core::int) → self::Class2);
+  self::expect(false, f2a is{ForNonNullableByDefault} (core::String) → self::Class2);
+  self::Class2 c2a = f2a(0){(core::int) → self::Class2};
+  self::expect(true, c2a is{ForNonNullableByDefault} self::Class2);
+  () → Null {
+    f2a(invalid-expression "pkg/front_end/testcases/constructor_tearoffs/inferred_constructor_tear_off.dart:52:9: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+    f2a(''); // error
+        ^" in "" as{TypeError,ForNonNullableByDefault} core::int){(core::int) → self::Class2};
+  };
+  dynamic f2b = #C2;
+  dynamic c2b = f2b{dynamic}.call(0);
+  self::expect(true, c2b is{ForNonNullableByDefault} self::Class2);
+  self::throws(() → dynamic => f2b{dynamic}.call(""));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, {core::bool inSoundModeOnly = #C3}) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print("Thrown: ${e}");
+    return;
+  }
+  if(!self::inSoundMode && inSoundModeOnly) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+constants  {
+  #C1 = constructor-tearoff self::Class1::•
+  #C2 = constructor-tearoff self::Class2::•
+  #C3 = false
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/inferred_non_proper_rename.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/inferred_non_proper_rename.dart.weak.modular.expect
new file mode 100644
index 0000000..5827e2a
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/inferred_non_proper_rename.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef F<X extends core::num> = self::A<X>;
+typedef G<unrelated Y extends core::Object? = dynamic> = self::A<core::int>;
+typedef H<X extends core::Object? = dynamic, unrelated Y extends core::Object? = dynamic> = self::A<X%>;
+class A<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static const field () → self::A<core::int> f1a = #C2;
+static const field () → self::A<core::int> f1b = #C2;
+static const field () → self::A<core::int> f1c = #C2;
+static const field () → self::A<core::int> g1a = #C2;
+static const field () → self::A<core::int> g1b = #C2;
+static const field () → self::A<core::int> g1c = #C2;
+static const field () → self::A<core::int> h1a = #C2;
+static const field () → self::A<core::int> h1b = #C2;
+static const field () → self::A<core::int> h1c = #C2;
+static method main() → dynamic {
+  self::test<core::int>();
+  core::identical(#C2, #C2);
+  core::identical(#C2, #C2);
+  core::identical(#C2, #C2);
+  core::identical(#C2, #C2);
+  core::identical(#C2, #C2);
+  core::identical(#C2, #C2);
+}
+static method test<T extends core::num>() → dynamic {
+  () → self::A<self::test::T> f2a = #C1<self::test::T>;
+  () → self::A<self::test::T> f2b = #C1<self::test::T>;
+  () → self::A<self::test::T> f2c = #C1<self::test::T>;
+  () → self::A<core::int> g2a = #C2;
+  () → self::A<core::int> g2b = #C2;
+  () → self::A<core::int> g2c = #C2;
+  () → self::A<self::test::T> h2a = #C1<self::test::T>;
+  () → self::A<self::test::T> h2b = #C1<self::test::T>;
+  () → self::A<self::test::T> h2c = #C1<self::test::T>;
+  self::expect(#C2, g2a);
+  self::expect(g2a, g2b);
+  if(self::inSoundMode) {
+    self::expect(g2a, g2c);
+  }
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = constructor-tearoff self::A::•
+  #C2 = instantiation #C1 <core::int*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/instantiation.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/instantiation.dart.weak.modular.expect
new file mode 100644
index 0000000..ba34a7a
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/instantiation.dart.weak.modular.expect
@@ -0,0 +1,73 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/instantiation.dart:16:40: Error: Inferred type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'A<X> Function<X extends num>(X)'.
+//  - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/instantiation.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// A<dynamic> Function(String) test5() => A.foo; // Error.
+//                                        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/instantiation.dart:17:40: Error: Inferred type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'A<X> Function<X extends num>(X)'.
+//  - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/instantiation.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// A<dynamic> Function(String) test6() => A.new; // Error.
+//                                        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/instantiation.dart:23:41: Error: Inferred type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'A<X> Function<X extends num>(X)'.
+//  - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/instantiation.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// A<dynamic> Function(String) test11() => A.bar; // Error.
+//                                         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::num> extends core::Object {
+  constructor foo(self::A::X x) → self::A<self::A::X>
+    : super core::Object::•() {}
+  constructor •(self::A::X x) → self::A<self::A::X>
+    : super core::Object::•() {}
+  static factory bar<X extends core::num>(self::A::bar::X x) → self::A<self::A::bar::X>
+    return new self::A::•<self::A::bar::X>(x);
+}
+static method test1() → (core::num) → self::A<core::num>
+  return #C2;
+static method test2() → (core::int) → self::A<core::int>
+  return #C3;
+static method test3() → (core::num) → self::A<core::num>
+  return #C5;
+static method test4() → (core::int) → self::A<core::int>
+  return #C6;
+static method test5() → (core::String) → self::A<dynamic>
+  return #C7;
+static method test6() → (core::String) → self::A<dynamic>
+  return #C8;
+static method test7() → (core::num) → self::A<dynamic>
+  return #C2;
+static method test8() → (core::num) → self::A<dynamic>
+  return #C5;
+static method test9() → (core::num) → self::A<core::num>
+  return #C10;
+static method test10() → (core::int) → self::A<core::int>
+  return #C11;
+static method test11() → (core::String) → self::A<dynamic>
+  return #C12;
+static method test12() → (core::num) → self::A<dynamic>
+  return #C10;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::A::foo
+  #C2 = instantiation #C1 <core::num*>
+  #C3 = instantiation #C1 <core::int*>
+  #C4 = constructor-tearoff self::A::•
+  #C5 = instantiation #C4 <core::num*>
+  #C6 = instantiation #C4 <core::int*>
+  #C7 = instantiation #C1 <core::String*>
+  #C8 = instantiation #C4 <core::String*>
+  #C9 = constructor-tearoff self::A::bar
+  #C10 = instantiation #C9 <core::num*>
+  #C11 = instantiation #C9 <core::int*>
+  #C12 = instantiation #C9 <core::String*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/issue46133.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/issue46133.dart.weak.modular.expect
new file mode 100644
index 0000000..912d264
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/issue46133.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue46133.dart:7:18: Error: Expected an identifier, but got '.'.
+// Try inserting an identifier before '.'.
+// test() => A.const.toString();
+//                  ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue46133.dart:7:13: Error: Expected an identifier, but got 'const'.
+// Try inserting an identifier before 'const'.
+// test() => A.const.toString();
+//             ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+static method test() → dynamic
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/issue46133.dart:7:13: Error: Expected an identifier, but got 'const'.
+Try inserting an identifier before 'const'.
+test() => A.const.toString();
+            ^^^^^";
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/issue46719.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/issue46719.dart.weak.modular.expect
new file mode 100644
index 0000000..6add537
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/issue46719.dart.weak.modular.expect
@@ -0,0 +1,67 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue46719.dart:24:10: Error: A constructor tear-off can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   A.named<int>.toString(); // error
+//          ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue46719.dart" as self;
+
+class A<T extends core::Object? = dynamic> extends core::Object {
+  constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+  constructor named() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+  method m<X extends core::Object? = dynamic>(self::A::m::X% x) → core::List<self::A::m::X%>
+    return <self::A::m::X%>[x];
+  static method n<X extends core::Object? = dynamic>(self::A::n::X% x) → core::List<self::A::n::X%>
+    return <self::A::n::X%>[x];
+}
+extension FunctionApplier on core::Function {
+  method applyAndPrint = self::FunctionApplier|applyAndPrint;
+  tearoff applyAndPrint = self::FunctionApplier|get#applyAndPrint;
+}
+static method m<X extends core::Object? = dynamic>(self::m::X% x) → core::List<self::m::X%>
+  return <self::m::X%>[x];
+static method FunctionApplier|applyAndPrint(lowered final core::Function #this, core::List<core::Object?> positionalArguments) → void
+  return core::print(core::Function::apply(#this, positionalArguments, #C1));
+static method FunctionApplier|get#applyAndPrint(lowered final core::Function #this) → (core::List<core::Object?>) → void
+  return (core::List<core::Object?> positionalArguments) → void => self::FunctionApplier|applyAndPrint(#this, positionalArguments);
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/issue46719.dart:24:10: Error: A constructor tear-off can't have type arguments after the constructor name.
+Try removing the type arguments or placing them after the class name.
+  A.named<int>.toString(); // error
+         ^";
+}
+static method main() → void {
+  self::A<dynamic> a = new self::A::•<dynamic>();
+  self::FunctionApplier|applyAndPrint(a.{self::A::m}{<X extends core::Object? = dynamic>(X%) → core::List<X%>}<core::int>, <core::Object?>[2]);
+  self::FunctionApplier|applyAndPrint(a.{self::A::m}{<X extends core::Object? = dynamic>(X%) → core::List<X%>}<core::String>, <core::Object?>["three"]);
+  self::FunctionApplier|applyAndPrint(#C3, <core::Object?>[2]);
+  self::FunctionApplier|applyAndPrint(#C4, <core::Object?>["three"]);
+  self::FunctionApplier|applyAndPrint(#C6, <core::Object?>[2]);
+  self::FunctionApplier|applyAndPrint(#C7, <core::Object?>["three"]);
+  self::FunctionApplier|applyAndPrint(#C3, <core::Object?>[2]);
+  self::FunctionApplier|applyAndPrint(#C4, <core::Object?>["three"]);
+  #C8.{core::Object::toString}(){() → core::String};
+  #C9.{core::Object::toString}(){() → core::String};
+}
+
+constants  {
+  #C1 = <core::Symbol*, dynamic>{)
+  #C2 = static-tearoff self::A::n
+  #C3 = instantiation #C2 <core::int*>
+  #C4 = instantiation #C2 <core::String*>
+  #C5 = static-tearoff self::m
+  #C6 = instantiation #C5 <core::int*>
+  #C7 = instantiation #C5 <core::String*>
+  #C8 = constructor-tearoff self::A::named
+  #C9 = instantiation #C8 <core::int*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/issue46887.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/issue46887.dart.weak.modular.expect
new file mode 100644
index 0000000..b032165
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/issue46887.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef b = core::int;
+typedef c = core::String;
+static method f(dynamic a, [dynamic b = #C1]) → core::String
+  return "${a}, ${b}";
+static method a<T1 extends core::Object? = dynamic, T2 extends core::Object? = dynamic>(core::int x) → core::String {
+  return "a<${self::a::T1%}, ${self::a::T2%}>(${x})";
+}
+static method main() → dynamic {
+  self::expect("${#C3}, null", self::f(#C3.{core::Object::toString}(){() → core::String}));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = null
+  #C2 = static-tearoff self::a
+  #C3 = instantiation #C2 <core::int*, core::String*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/issue46890.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/issue46890.dart.weak.modular.expect
new file mode 100644
index 0000000..9459fcb
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/issue46890.dart.weak.modular.expect
@@ -0,0 +1,75 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue46890.dart:22:14: Error: A constructor tear-off can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   List.filled<int>; // Error.
+//              ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue46890.dart:23:8: Error: A constructor tear-off can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   A.foo<int>; // Error.
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue46890.dart:24:8: Error: A constructor tear-off can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   A.bar<int>; // Error.
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue46890.dart:25:8: Error: A constructor tear-off can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   A.baz<int>; // Error.
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor foo() → self::A<self::A::X%>
+    : super core::Object::•() {}
+  static factory bar<X extends core::Object? = dynamic>() → self::A<self::A::bar::X%>
+    return new self::A::foo<self::A::bar::X%>();
+  static factory baz<X extends core::Object? = dynamic>() → self::A<self::A::baz::X%>
+    return self::A::bar<self::A::baz::X%>();
+}
+static method test() → dynamic {
+  #C2;
+  #C3;
+  #C4;
+  #C5;
+  #C6;
+  #C7;
+  #C8;
+  #C9;
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/issue46890.dart:22:14: Error: A constructor tear-off can't have type arguments after the constructor name.
+Try removing the type arguments or placing them after the class name.
+  List.filled<int>; // Error.
+             ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/issue46890.dart:23:8: Error: A constructor tear-off can't have type arguments after the constructor name.
+Try removing the type arguments or placing them after the class name.
+  A.foo<int>; // Error.
+       ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/issue46890.dart:24:8: Error: A constructor tear-off can't have type arguments after the constructor name.
+Try removing the type arguments or placing them after the class name.
+  A.bar<int>; // Error.
+       ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/issue46890.dart:25:8: Error: A constructor tear-off can't have type arguments after the constructor name.
+Try removing the type arguments or placing them after the class name.
+  A.baz<int>; // Error.
+       ^";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::A::baz
+  #C2 = constructor-tearoff core::List::filled
+  #C3 = constructor-tearoff self::A::foo
+  #C4 = constructor-tearoff self::A::bar
+  #C5 = redirecting-factory-tearoff self::A::baz
+  #C6 = instantiation #C2 <core::int*>
+  #C7 = instantiation #C3 <core::int*>
+  #C8 = instantiation #C4 <core::int*>
+  #C9 = instantiation #C5 <core::int*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/issue46925.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/issue46925.dart.weak.modular.expect
new file mode 100644
index 0000000..9c76f69
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/issue46925.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue46925.dart:18:16: Error: Function invocation is not a constant expression.
+//   const c1 = v1(3, 14);
+//                ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue46925.dart:19:16: Error: Function invocation is not a constant expression.
+//   const c2 = v1(3, 14);
+//                ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue46925.dart:20:16: Error: Function invocation is not a constant expression.
+//   const c3 = v2();
+//                ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue46925.dart:21:16: Error: Function invocation is not a constant expression.
+//   const c4 = v2();
+//                ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue46925.dart:22:16: Error: Function invocation is not a constant expression.
+//   const c5 = v3(3, 14);
+//                ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue46925.dart:23:16: Error: Function invocation is not a constant expression.
+//   const c6 = v4();
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+class MyClass<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field dynamic a;
+  const constructor •(core::int i, core::int j) → self::MyClass<self::MyClass::T%>
+    : self::MyClass::a = i.{core::num::+}(j){(core::num) → core::int}, super core::Object::•()
+    ;
+  const constructor constr() → self::MyClass<self::MyClass::T%>
+    : self::MyClass::a = 0, super core::Object::•()
+    ;
+}
+static method test() → dynamic {
+  const self::MyClass<core::String> c1 = invalid-expression "Function invocation is not a constant expression.";
+  const self::MyClass<core::String> c2 = invalid-expression "Function invocation is not a constant expression.";
+  const self::MyClass<core::int> c3 = invalid-expression "Function invocation is not a constant expression.";
+  const self::MyClass<core::int> c4 = invalid-expression "Function invocation is not a constant expression.";
+  const self::MyClass<core::int> c5 = invalid-expression "Function invocation is not a constant expression.";
+  const self::MyClass<core::String> c6 = invalid-expression "Function invocation is not a constant expression.";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/issue47069.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/issue47069.dart.weak.modular.expect
new file mode 100644
index 0000000..9f3e10b
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/issue47069.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue47069.dart:7:2: Error: Couldn't find constructor 'func'.
+// @func()
+//  ^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue47069.dart:9:9: Error: Couldn't find constructor 'func'.
+//   const func();
+//         ^^^^
+//
+import self as self;
+
+static method func() → dynamic {}
+@invalid-expression "pkg/front_end/testcases/constructor_tearoffs/issue47069.dart:7:2: Error: Couldn't find constructor 'func'.
+@func()
+ ^^^^"
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/issue47069.dart:9:9: Error: Couldn't find constructor 'func'.
+  const func();
+        ^^^^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/issue47071.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/issue47071.dart.weak.modular.expect
new file mode 100644
index 0000000..a4ce712
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/issue47071.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue47071.dart:8:7: Error: Couldn't find constructor 'a'.
+//   new a();
+//       ^
+//
+import self as self;
+
+static field dynamic a;
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/issue47071.dart:8:7: Error: Couldn't find constructor 'a'.
+  new a();
+      ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/issue47075.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/issue47075.dart.weak.modular.expect
new file mode 100644
index 0000000..1d24b72
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/issue47075.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue47075.dart:6:7: Error: 'new' can't be used as an identifier because it's a keyword.
+// Try renaming this to be an identifier that isn't a keyword.
+//   int new = 42;
+//       ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue47075.dart:10:11: Error: 'new' can only be used as a constructor reference.
+//   new C().new is int;
+//           ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue47075.dart:12:7: Error: 'new' can only be used as a constructor reference.
+//   foo.new;
+//       ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue47075.dart:13:7: Error: 'new' can only be used as a constructor reference.
+//   foo.new();
+//       ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field core::int new = 42;
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+static method test() → dynamic {
+  new self::C::•().{self::C::new}{core::int} is{ForNonNullableByDefault} core::int;
+  dynamic foo;
+  foo{dynamic}.new;
+  foo{dynamic}.new();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/issue47079.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/issue47079.dart.weak.modular.expect
new file mode 100644
index 0000000..17917a9
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/issue47079.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/issue47079.dart:6:7: Error: Couldn't find constructor 'A'.
+//   new A();
+//       ^
+//
+import self as self;
+
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/issue47079.dart:6:7: Error: Couldn't find constructor 'A'.
+  new A();
+      ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/issue47154a.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/issue47154a.dart.weak.modular.expect
new file mode 100644
index 0000000..9af80b0
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/issue47154a.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  final field (core::int) → core::int x;
+  const constructor •(core::bool b) → self::A
+    : self::A::x = (b ?{<X extends core::Object? = dynamic>(X%) → X%} #C1 : #C2)<core::int>, super core::Object::•()
+    ;
+}
+static method id<X extends core::Object? = dynamic>(self::id::X% x) → self::id::X%
+  return x;
+static method other<X extends core::Object? = dynamic>(self::other::X% x) → self::other::X%
+  return throw "${x}";
+static method main() → void {
+  core::print("${#C3}, ${#C1}, ${#C3}, ${#C4}");
+}
+
+constants  {
+  #C1 = static-tearoff self::id
+  #C2 = static-tearoff self::other
+  #C3 = instantiation #C1 <core::int*>
+  #C4 = self::A {x:#C3}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue47154a.dart:
+- A. (from org-dartlang-testcase:///issue47154a.dart:7:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/constructor_tearoffs/issue47154b.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/issue47154b.dart.weak.modular.expect
new file mode 100644
index 0000000..a593732
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/issue47154b.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  final field (core::int) → core::int x;
+  const constructor •(core::bool b) → self::A
+    : self::A::x = b ?{(core::int) → core::int} #C2 : #C4, super core::Object::•()
+    ;
+}
+static method id<X extends core::Object? = dynamic>(self::id::X% x) → self::id::X%
+  return x;
+static method other<X extends core::Object? = dynamic>(self::other::X% x) → self::other::X%
+  return throw "${x}";
+static method main() → void {
+  core::print("${#C2}, ${#C1}, ${#C2}, ${#C5}");
+}
+
+constants  {
+  #C1 = static-tearoff self::id
+  #C2 = instantiation #C1 <core::int*>
+  #C3 = static-tearoff self::other
+  #C4 = instantiation #C3 <core::int*>
+  #C5 = self::A {x:#C2}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue47154b.dart:
+- A. (from org-dartlang-testcase:///issue47154b.dart:7:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/constructor_tearoffs/issue47154c.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/issue47154c.dart.weak.modular.expect
new file mode 100644
index 0000000..691f3a6
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/issue47154c.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field core::List<self::A::X%> x;
+  const constructor •(dynamic x) → self::A<self::A::X%>
+    : self::A::x = x is{ForNonNullableByDefault} core::List<self::A::X%> ?{core::List<self::A::X%>} x{core::List<self::A::X%>} : x as{ForNonNullableByDefault} core::List<self::A::X%>, super core::Object::•()
+    ;
+}
+class B<X extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field (self::B::X%) → void f;
+  const constructor •() → self::B<self::B::X%>
+    : self::B::f = #C1<self::B::X%>, super core::Object::•()
+    ;
+}
+class C<X extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field dynamic f;
+  const constructor •() → self::C<self::C::X%>
+    : self::C::f = #C1<self::C::X%>, super core::Object::•()
+    ;
+}
+static method m<X extends core::Object? = dynamic>(self::m::X% x) → void {}
+static method main() → void {
+  #C4;
+  core::print((#C6.{self::B::f}{(core::String) → void} as{TypeError,CovarianceCheck,ForNonNullableByDefault} (core::String) → void).{core::Object::runtimeType}{core::Type});
+  core::print(#C7.{self::C::f}{dynamic}.{core::Object::runtimeType}{core::Type});
+}
+
+constants  {
+  #C1 = static-tearoff self::m
+  #C2 = 1
+  #C3 = <core::int*>[#C2]
+  #C4 = self::A<core::int*> {x:#C3}
+  #C5 = instantiation #C1 <core::String*>
+  #C6 = self::B<core::String*> {f:#C5}
+  #C7 = self::C<core::String*> {f:#C5}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue47154c.dart:
+- A. (from org-dartlang-testcase:///issue47154c.dart:8:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- B. (from org-dartlang-testcase:///issue47154c.dart:16:9)
+- C. (from org-dartlang-testcase:///issue47154c.dart:22:9)
diff --git a/pkg/front_end/testcases/constructor_tearoffs/issue47462.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/issue47462.dart.weak.modular.expect
new file mode 100644
index 0000000..ff4b5b0
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/issue47462.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef MyList<T extends core::num> = core::List<T>;
+static method main() → dynamic {}
+static method test() → dynamic {
+  self::expect(true, #C1);
+  self::expect(false, #C2);
+  self::expect(true, core::identical(#C4, #C4));
+  self::expect(false, core::identical(#C4, #C6));
+  (core::int, core::num, {growable: core::bool}) → core::List<core::num> v1 = #C4;
+  (core::int, core::num, {growable: core::bool}) → core::List<core::num> v2 = #C4;
+  (core::int, core::num, {growable: core::bool}) → core::List<core::num> v3 = #C6;
+  core::bool v4 = core::identical(v1, v2);
+  core::bool v5 = core::identical(v1, v3);
+  self::expect(true, v4);
+  self::expect(false, v5);
+  self::expect(true, core::identical(v1, v2));
+  self::expect(false, core::identical(v1, v3));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = true
+  #C2 = false
+  #C3 = constructor-tearoff core::List::filled
+  #C4 = instantiation #C3 <core::num*>
+  #C5 = typedef-tearoff <T extends core::num>.(#C3<T>)
+  #C6 = instantiation #C5 <core::num*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart
index 19d9464..a192018 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart
@@ -14,6 +14,13 @@
         Alias.impl(),
         ImplAlias<String>()
       ]});
+
+  const Class.named(
+      {this.constants = const [
+        Const.impl(),
+        Alias.impl(),
+        ImplAlias<String>()
+      ]});
 }
 
 typedef Alias = Const;
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.strong.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.strong.expect
index df41444..0e8c87e 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.strong.expect
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.strong.expect
@@ -6,7 +6,15 @@
 // Try changing type arguments so that they conform to the bounds.
 //         ImplAlias<String>()
 //         ^
-// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:25:19: Context: This is the type variable whose bound isn't conformed to.
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:32:19: Context: This is the type variable whose bound isn't conformed to.
+// typedef ImplAlias<T extends num> = _ConstImpl<T>;
+//                   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:22:9: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'ImplAlias'.
+// Try changing type arguments so that they conform to the bounds.
+//         ImplAlias<String>()
+//         ^
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:32:19: Context: This is the type variable whose bound isn't conformed to.
 // typedef ImplAlias<T extends num> = _ConstImpl<T>;
 //                   ^
 //
@@ -15,13 +23,18 @@
 
 typedef Alias = self::Const;
 typedef ImplAlias<T extends core::num> = self::_ConstImpl<T>;
-class Class extends core::Object {
+class Class extends core::Object /*hasConstConstructor*/  {
   final field core::List<self::Const> constants;
   constructor •({core::List<self::Const> constants = #C3}) → self::Class
     : self::Class::constants = constants, super core::Object::•()
     ;
+  const constructor named({core::List<self::Const> constants = #C3}) → self::Class
+    : self::Class::constants = constants, super core::Object::•()
+    ;
   static method _#new#tearOff({core::List<self::Const> constants = #C3}) → self::Class
     return new self::Class::•(constants: constants);
+  static method _#named#tearOff({core::List<self::Const> constants = #C3}) → self::Class
+    return new self::Class::named(constants: constants);
 }
 abstract class Const extends core::Object {
   static final field dynamic _redirecting# = <dynamic>[#C4]/*isLegacy*/;
@@ -51,5 +64,5 @@
 
 Constructor coverage from constants:
 org-dartlang-testcase:///const_redirect.dart:
-- _ConstImpl. (from org-dartlang-testcase:///const_redirect.dart:28:9)
+- _ConstImpl. (from org-dartlang-testcase:///const_redirect.dart:35:9)
 - Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.strong.transformed.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.strong.transformed.expect
index df41444..0e8c87e 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.strong.transformed.expect
@@ -6,7 +6,15 @@
 // Try changing type arguments so that they conform to the bounds.
 //         ImplAlias<String>()
 //         ^
-// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:25:19: Context: This is the type variable whose bound isn't conformed to.
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:32:19: Context: This is the type variable whose bound isn't conformed to.
+// typedef ImplAlias<T extends num> = _ConstImpl<T>;
+//                   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:22:9: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'ImplAlias'.
+// Try changing type arguments so that they conform to the bounds.
+//         ImplAlias<String>()
+//         ^
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:32:19: Context: This is the type variable whose bound isn't conformed to.
 // typedef ImplAlias<T extends num> = _ConstImpl<T>;
 //                   ^
 //
@@ -15,13 +23,18 @@
 
 typedef Alias = self::Const;
 typedef ImplAlias<T extends core::num> = self::_ConstImpl<T>;
-class Class extends core::Object {
+class Class extends core::Object /*hasConstConstructor*/  {
   final field core::List<self::Const> constants;
   constructor •({core::List<self::Const> constants = #C3}) → self::Class
     : self::Class::constants = constants, super core::Object::•()
     ;
+  const constructor named({core::List<self::Const> constants = #C3}) → self::Class
+    : self::Class::constants = constants, super core::Object::•()
+    ;
   static method _#new#tearOff({core::List<self::Const> constants = #C3}) → self::Class
     return new self::Class::•(constants: constants);
+  static method _#named#tearOff({core::List<self::Const> constants = #C3}) → self::Class
+    return new self::Class::named(constants: constants);
 }
 abstract class Const extends core::Object {
   static final field dynamic _redirecting# = <dynamic>[#C4]/*isLegacy*/;
@@ -51,5 +64,5 @@
 
 Constructor coverage from constants:
 org-dartlang-testcase:///const_redirect.dart:
-- _ConstImpl. (from org-dartlang-testcase:///const_redirect.dart:28:9)
+- _ConstImpl. (from org-dartlang-testcase:///const_redirect.dart:35:9)
 - Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.textual_outline.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.textual_outline.expect
index 2453b30..4601a8e 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.textual_outline.expect
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.textual_outline.expect
@@ -6,6 +6,12 @@
         Alias.impl(),
         ImplAlias<String>()
       ]});
+  const Class.named(
+      {this.constants = const [
+        Const.impl(),
+        Alias.impl(),
+        ImplAlias<String>()
+      ]});
 }
 
 typedef Alias = Const;
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.textual_outline_modelled.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.textual_outline_modelled.expect
index 615c4c2..3c229e1 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.textual_outline_modelled.expect
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.textual_outline_modelled.expect
@@ -9,6 +9,12 @@
         Alias.impl(),
         ImplAlias<String>()
       ]});
+  const Class.named(
+      {this.constants = const [
+        Const.impl(),
+        Alias.impl(),
+        ImplAlias<String>()
+      ]});
   final List<Const> constants;
 }
 
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.weak.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.weak.expect
index 38c6a94..f957d96 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.weak.expect
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.weak.expect
@@ -6,7 +6,15 @@
 // Try changing type arguments so that they conform to the bounds.
 //         ImplAlias<String>()
 //         ^
-// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:25:19: Context: This is the type variable whose bound isn't conformed to.
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:32:19: Context: This is the type variable whose bound isn't conformed to.
+// typedef ImplAlias<T extends num> = _ConstImpl<T>;
+//                   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:22:9: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'ImplAlias'.
+// Try changing type arguments so that they conform to the bounds.
+//         ImplAlias<String>()
+//         ^
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:32:19: Context: This is the type variable whose bound isn't conformed to.
 // typedef ImplAlias<T extends num> = _ConstImpl<T>;
 //                   ^
 //
@@ -15,13 +23,18 @@
 
 typedef Alias = self::Const;
 typedef ImplAlias<T extends core::num> = self::_ConstImpl<T>;
-class Class extends core::Object {
+class Class extends core::Object /*hasConstConstructor*/  {
   final field core::List<self::Const> constants;
   constructor •({core::List<self::Const> constants = #C3}) → self::Class
     : self::Class::constants = constants, super core::Object::•()
     ;
+  const constructor named({core::List<self::Const> constants = #C3}) → self::Class
+    : self::Class::constants = constants, super core::Object::•()
+    ;
   static method _#new#tearOff({core::List<self::Const> constants = #C3}) → self::Class
     return new self::Class::•(constants: constants);
+  static method _#named#tearOff({core::List<self::Const> constants = #C3}) → self::Class
+    return new self::Class::named(constants: constants);
 }
 abstract class Const extends core::Object {
   static final field dynamic _redirecting# = <dynamic>[#C4]/*isLegacy*/;
@@ -51,5 +64,5 @@
 
 Constructor coverage from constants:
 org-dartlang-testcase:///const_redirect.dart:
-- _ConstImpl. (from org-dartlang-testcase:///const_redirect.dart:28:9)
+- _ConstImpl. (from org-dartlang-testcase:///const_redirect.dart:35:9)
 - Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.weak.modular.expect
new file mode 100644
index 0000000..f957d96
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.weak.modular.expect
@@ -0,0 +1,68 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:15:9: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'ImplAlias'.
+// Try changing type arguments so that they conform to the bounds.
+//         ImplAlias<String>()
+//         ^
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:32:19: Context: This is the type variable whose bound isn't conformed to.
+// typedef ImplAlias<T extends num> = _ConstImpl<T>;
+//                   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:22:9: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'ImplAlias'.
+// Try changing type arguments so that they conform to the bounds.
+//         ImplAlias<String>()
+//         ^
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:32:19: Context: This is the type variable whose bound isn't conformed to.
+// typedef ImplAlias<T extends num> = _ConstImpl<T>;
+//                   ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef Alias = self::Const;
+typedef ImplAlias<T extends core::num> = self::_ConstImpl<T>;
+class Class extends core::Object /*hasConstConstructor*/  {
+  final field core::List<self::Const> constants;
+  constructor •({core::List<self::Const> constants = #C3}) → self::Class
+    : self::Class::constants = constants, super core::Object::•()
+    ;
+  const constructor named({core::List<self::Const> constants = #C3}) → self::Class
+    : self::Class::constants = constants, super core::Object::•()
+    ;
+  static method _#new#tearOff({core::List<self::Const> constants = #C3}) → self::Class
+    return new self::Class::•(constants: constants);
+  static method _#named#tearOff({core::List<self::Const> constants = #C3}) → self::Class
+    return new self::Class::named(constants: constants);
+}
+abstract class Const extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C4]/*isLegacy*/;
+  static factory impl() → self::Const
+    return new self::_ConstImpl::•<dynamic>();
+  static method _#impl#tearOff() → self::Const
+    return new self::_ConstImpl::•<dynamic>();
+}
+class _ConstImpl<T extends core::Object? = dynamic> extends core::Object implements self::Const /*hasConstConstructor*/  {
+  const constructor •() → self::_ConstImpl<self::_ConstImpl::T%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::_ConstImpl<self::_ConstImpl::_#new#tearOff::T%>
+    return new self::_ConstImpl::•<self::_ConstImpl::_#new#tearOff::T%>();
+}
+static method main() → dynamic {}
+static method _#ImplAlias#new#tearOff<T extends core::num>() → self::_ConstImpl<self::_#ImplAlias#new#tearOff::T>
+  return new self::_ConstImpl::•<self::_#ImplAlias#new#tearOff::T>();
+
+constants  {
+  #C1 = self::_ConstImpl<dynamic> {}
+  #C2 = self::_ConstImpl<core::String*> {}
+  #C3 = <self::Const*>[#C1, #C1, #C2]
+  #C4 = constructor-tearoff self::Const::impl
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///const_redirect.dart:
+- _ConstImpl. (from org-dartlang-testcase:///const_redirect.dart:35:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.weak.outline.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.weak.outline.expect
index 7fffaa8..b497969 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.weak.outline.expect
@@ -1,15 +1,39 @@
 library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:15:9: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'ImplAlias'.
+// Try changing type arguments so that they conform to the bounds.
+//         ImplAlias<String>()
+//         ^
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:32:19: Context: This is the type variable whose bound isn't conformed to.
+// typedef ImplAlias<T extends num> = _ConstImpl<T>;
+//                   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:22:9: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'ImplAlias'.
+// Try changing type arguments so that they conform to the bounds.
+//         ImplAlias<String>()
+//         ^
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:32:19: Context: This is the type variable whose bound isn't conformed to.
+// typedef ImplAlias<T extends num> = _ConstImpl<T>;
+//                   ^
+//
 import self as self;
 import "dart:core" as core;
 
 typedef Alias = self::Const;
 typedef ImplAlias<T extends core::num> = self::_ConstImpl<T>;
-class Class extends core::Object {
+class Class extends core::Object /*hasConstConstructor*/  {
   final field core::List<self::Const> constants;
-  constructor •({core::List<self::Const> constants}) → self::Class
+  constructor •({core::List<self::Const> constants = const <self::Const>[const self::_ConstImpl::•<dynamic>(), const self::_ConstImpl::•<dynamic>(), const self::_ConstImpl::•<core::String>()]}) → self::Class
+    ;
+  const constructor named({core::List<self::Const> constants = const <self::Const>[const self::_ConstImpl::•<dynamic>(), const self::_ConstImpl::•<dynamic>(), const self::_ConstImpl::•<core::String>()]}) → self::Class
+    : self::Class::constants = constants, super core::Object::•()
     ;
   static method _#new#tearOff({core::List<self::Const> constants}) → self::Class
     return new self::Class::•(constants: constants);
+  static method _#named#tearOff({core::List<self::Const> constants}) → self::Class
+    return new self::Class::named(constants: constants);
 }
 abstract class Const extends core::Object {
   static final field dynamic _redirecting# = <dynamic>[self::Const::impl]/*isLegacy*/;
@@ -32,5 +56,7 @@
 
 
 Extra constant evaluation status:
-Evaluated: ConstructorTearOff @ org-dartlang-testcase:///const_redirect.dart:21:16 -> ConstructorTearOffConstant(Const.impl)
-Extra constant evaluation: evaluated: 8, effectively constant: 1
+Evaluated: ListLiteral @ org-dartlang-testcase:///const_redirect.dart:12:25 -> ListConstant(const <Const*>[const _ConstImpl<dynamic>{}, const _ConstImpl<dynamic>{}, const _ConstImpl<String*>{}])
+Evaluated: ListLiteral @ org-dartlang-testcase:///const_redirect.dart:19:25 -> ListConstant(const <Const*>[const _ConstImpl<dynamic>{}, const _ConstImpl<dynamic>{}, const _ConstImpl<String*>{}])
+Evaluated: ConstructorTearOff @ org-dartlang-testcase:///const_redirect.dart:28:16 -> ConstructorTearOffConstant(Const.impl)
+Extra constant evaluation: evaluated: 13, effectively constant: 3
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.weak.transformed.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.weak.transformed.expect
index 38c6a94..f957d96 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart.weak.transformed.expect
@@ -6,7 +6,15 @@
 // Try changing type arguments so that they conform to the bounds.
 //         ImplAlias<String>()
 //         ^
-// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:25:19: Context: This is the type variable whose bound isn't conformed to.
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:32:19: Context: This is the type variable whose bound isn't conformed to.
+// typedef ImplAlias<T extends num> = _ConstImpl<T>;
+//                   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:22:9: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'ImplAlias'.
+// Try changing type arguments so that they conform to the bounds.
+//         ImplAlias<String>()
+//         ^
+// pkg/front_end/testcases/constructor_tearoffs/lowering/const_redirect.dart:32:19: Context: This is the type variable whose bound isn't conformed to.
 // typedef ImplAlias<T extends num> = _ConstImpl<T>;
 //                   ^
 //
@@ -15,13 +23,18 @@
 
 typedef Alias = self::Const;
 typedef ImplAlias<T extends core::num> = self::_ConstImpl<T>;
-class Class extends core::Object {
+class Class extends core::Object /*hasConstConstructor*/  {
   final field core::List<self::Const> constants;
   constructor •({core::List<self::Const> constants = #C3}) → self::Class
     : self::Class::constants = constants, super core::Object::•()
     ;
+  const constructor named({core::List<self::Const> constants = #C3}) → self::Class
+    : self::Class::constants = constants, super core::Object::•()
+    ;
   static method _#new#tearOff({core::List<self::Const> constants = #C3}) → self::Class
     return new self::Class::•(constants: constants);
+  static method _#named#tearOff({core::List<self::Const> constants = #C3}) → self::Class
+    return new self::Class::named(constants: constants);
 }
 abstract class Const extends core::Object {
   static final field dynamic _redirecting# = <dynamic>[#C4]/*isLegacy*/;
@@ -51,5 +64,5 @@
 
 Constructor coverage from constants:
 org-dartlang-testcase:///const_redirect.dart:
-- _ConstImpl. (from org-dartlang-testcase:///const_redirect.dart:28:9)
+- _ConstImpl. (from org-dartlang-testcase:///const_redirect.dart:35:9)
 - Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..678c59b
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart.weak.modular.expect
@@ -0,0 +1,230 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:73:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f3a(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:74:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f3a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:89:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f4a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:103:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f5a(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:104:8: Error: Too many positional arguments: 2 allowed, but 3 found.
+// Try removing the extra positional arguments.
+//     f5a(42, 87, 123); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:116:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f6a(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:117:8: Error: Required named parameter 'field3' must be provided.
+//     f6a(42); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:118:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f6a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:119:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f6a(field1: 87, field2: 87); // error
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff() → self::Class1
+    return new self::Class1::•();
+}
+class Class2 extends core::Object {
+  constructor named() → self::Class2
+    : super core::Object::•()
+    ;
+  static method _#named#tearOff() → self::Class2
+    return new self::Class2::named();
+}
+class Class3 extends core::Object {
+  final field core::int field;
+  constructor •(core::int field) → self::Class3
+    : self::Class3::field = field, super core::Object::•()
+    ;
+  static method _#new#tearOff(core::int field) → self::Class3
+    return new self::Class3::•(field);
+}
+class Class4 extends core::Object {
+  final field core::int? field;
+  constructor •([core::int? field = #C1]) → self::Class4
+    : self::Class4::field = field, super core::Object::•()
+    ;
+  static method _#new#tearOff([core::int? field = #C1]) → self::Class4
+    return new self::Class4::•(field);
+}
+class Class5 extends core::Object {
+  final field core::int field1;
+  final field core::int? field2;
+  constructor •(core::int field1, [core::int? field2 = #C1]) → self::Class5
+    : self::Class5::field1 = field1, self::Class5::field2 = field2, super core::Object::•()
+    ;
+  static method _#new#tearOff(core::int field1, [core::int? field2 = #C1]) → self::Class5
+    return new self::Class5::•(field1, field2);
+}
+class Class6 extends core::Object {
+  final field core::int field1;
+  final field core::int? field2;
+  final field core::int field3;
+  constructor •(core::int field1, {core::int? field2 = #C1, required core::int field3 = #C1}) → self::Class6
+    : self::Class6::field1 = field1, self::Class6::field2 = field2, self::Class6::field3 = field3, super core::Object::•()
+    ;
+  static method _#new#tearOff(core::int field1, {core::int? field2 = #C1, required core::int field3 = #C1}) → self::Class6
+    return new self::Class6::•(field1, field2: field2, field3: field3);
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static method main() → dynamic {
+  core::print("inSoundMode: ${self::inSoundMode}");
+  self::testNoArgs();
+  self::testArgs();
+}
+static method testNoArgs() → dynamic {
+  () → self::Class1 f1a = #C2;
+  self::Class1 c1a = f1a(){() → self::Class1};
+  self::expect(true, c1a is{ForNonNullableByDefault} self::Class1);
+  dynamic f1b = #C2;
+  dynamic c1b = f1b{dynamic}.call();
+  self::expect(true, c1b is{ForNonNullableByDefault} self::Class1);
+  self::expect(true, core::identical(f1a, f1b));
+  () → self::Class2 f2a = #C3;
+  self::Class2 c2a = f2a(){() → self::Class2};
+  self::expect(true, c2a is{ForNonNullableByDefault} self::Class2);
+  dynamic f2b = #C3;
+  dynamic c2b = f2b{dynamic}.call();
+  self::expect(true, c2b is{ForNonNullableByDefault} self::Class2);
+  self::expect(true, core::identical(f2a, f2b));
+}
+static method testArgs() → dynamic {
+  (core::int) → self::Class3 f3a = #C4;
+  self::Class3 c3a = f3a(42){(core::int) → self::Class3};
+  self::expect(42, c3a.{self::Class3::field}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:73:8: Error: Too few positional arguments: 1 required, 0 given.
+    f3a(); // error
+       ^" in f3a{<inapplicable>}.();
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:74:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f3a(42, 87); // error
+       ^" in f3a{<inapplicable>}.(42, 87);
+  };
+  dynamic f3b = #C4;
+  dynamic c3b = f3b{dynamic}.call(87);
+  self::expect(87, c3b{dynamic}.field);
+  self::throws(() → dynamic => f3b{dynamic}.call());
+  self::throws(() → dynamic => f3b{dynamic}.call(42, 87));
+  ([core::int?]) → self::Class4 f4a = #C5;
+  self::Class4 c4a = f4a(){([core::int?]) → self::Class4};
+  self::expect(null, c4a.{self::Class4::field}{core::int?});
+  self::Class4 c4b = f4a(42){([core::int?]) → self::Class4};
+  self::expect(42, c4b.{self::Class4::field}{core::int?});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:89:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f4a(42, 87); // error
+       ^" in f4a{<inapplicable>}.(42, 87);
+  };
+  dynamic f4b = #C5;
+  self::throws(() → dynamic => f4b{dynamic}.call(42, 87));
+  (core::int, [core::int?]) → self::Class5 f5a = #C6;
+  self::Class5 c5a = f5a(42){(core::int, [core::int?]) → self::Class5};
+  self::expect(42, c5a.{self::Class5::field1}{core::int});
+  self::expect(null, c5a.{self::Class5::field2}{core::int?});
+  self::Class5 c5b = f5a(87, 42){(core::int, [core::int?]) → self::Class5};
+  self::expect(87, c5b.{self::Class5::field1}{core::int});
+  self::expect(42, c5b.{self::Class5::field2}{core::int?});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:103:8: Error: Too few positional arguments: 1 required, 0 given.
+    f5a(); // error
+       ^" in f5a{<inapplicable>}.();
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:104:8: Error: Too many positional arguments: 2 allowed, but 3 found.
+Try removing the extra positional arguments.
+    f5a(42, 87, 123); // error
+       ^" in f5a{<inapplicable>}.(42, 87, 123);
+  };
+  dynamic f5b = #C6;
+  self::throws(() → dynamic => f5b{dynamic}.call());
+  self::throws(() → dynamic => f5b{dynamic}.call(42, 87, 123));
+  (core::int, {field2: core::int?, required field3: core::int}) → self::Class6 f6a = #C7;
+  self::Class6 c6a = f6a(42, field3: 87){(core::int, {field2: core::int?, required field3: core::int}) → self::Class6};
+  self::expect(42, c6a.{self::Class6::field1}{core::int});
+  self::expect(null, c6a.{self::Class6::field2}{core::int?});
+  self::expect(87, c6a.{self::Class6::field3}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:116:8: Error: Too few positional arguments: 1 required, 0 given.
+    f6a(); // error
+       ^" in f6a{<inapplicable>}.();
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:117:8: Error: Required named parameter 'field3' must be provided.
+    f6a(42); // error
+       ^" in f6a{<inapplicable>}.(42);
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:118:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f6a(42, 87); // error
+       ^" in f6a{<inapplicable>}.(42, 87);
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off.dart:119:8: Error: Too few positional arguments: 1 required, 0 given.
+    f6a(field1: 87, field2: 87); // error
+       ^" in f6a{<inapplicable>}.(field1: 87, field2: 87);
+  };
+  self::Class6 c6b = f6a(42, field2: 123, field3: 87){(core::int, {field2: core::int?, required field3: core::int}) → self::Class6};
+  self::expect(42, c6b.{self::Class6::field1}{core::int});
+  self::expect(123, c6b.{self::Class6::field2}{core::int?});
+  self::expect(87, c6b.{self::Class6::field3}{core::int});
+  self::Class6 c6c = f6a(87, field3: 42, field2: 123){(core::int, {field2: core::int?, required field3: core::int}) → self::Class6};
+  self::expect(87, c6c.{self::Class6::field1}{core::int});
+  self::expect(123, c6c.{self::Class6::field2}{core::int?});
+  self::expect(42, c6c.{self::Class6::field3}{core::int});
+  dynamic f6b = #C7;
+  self::throws(() → dynamic => f6b{dynamic}.call());
+  self::throws(() → dynamic => f6b{dynamic}.call(42), inSoundModeOnly: true);
+  self::throws(() → dynamic => f6b{dynamic}.call(42, 87), inSoundModeOnly: true);
+  self::throws(() → dynamic => f6b{dynamic}.call(field1: 87, field2: 87));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, {core::bool inSoundModeOnly = #C8}) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print("Thrown: ${e}");
+    return;
+  }
+  if(!self::inSoundMode && inSoundModeOnly) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+constants  {
+  #C1 = null
+  #C2 = static-tearoff self::Class1::_#new#tearOff
+  #C3 = static-tearoff self::Class2::_#named#tearOff
+  #C4 = static-tearoff self::Class3::_#new#tearOff
+  #C5 = static-tearoff self::Class4::_#new#tearOff
+  #C6 = static-tearoff self::Class5::_#new#tearOff
+  #C7 = static-tearoff self::Class6::_#new#tearOff
+  #C8 = false
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_default_values.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_default_values.dart.weak.modular.expect
new file mode 100644
index 0000000..9db8c5f
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_default_values.dart.weak.modular.expect
@@ -0,0 +1,98 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_default_values.dart:31:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f1a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_default_values.dart:47:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//     f2a(87); // error
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  final field core::int field;
+  constructor •([core::int field = #C1]) → self::Class1
+    : self::Class1::field = field, super core::Object::•()
+    ;
+  static method _#new#tearOff([core::int field = #C1]) → self::Class1
+    return new self::Class1::•(field);
+}
+class Class2 extends core::Object {
+  final field core::int field;
+  constructor •({core::int field = #C1}) → self::Class2
+    : self::Class2::field = field, super core::Object::•()
+    ;
+  static method _#new#tearOff({core::int field = #C1}) → self::Class2
+    return new self::Class2::•(field: field);
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static method main() → dynamic {
+  core::print("inSoundMode: ${self::inSoundMode}");
+  self::testDefaultValues();
+}
+static method testDefaultValues() → void {
+  ([core::int]) → self::Class1 f1a = #C2;
+  self::Class1 c1a = f1a(){([core::int]) → self::Class1};
+  self::expect(42, c1a.{self::Class1::field}{core::int});
+  self::Class1 c1b = f1a(87){([core::int]) → self::Class1};
+  self::expect(87, c1b.{self::Class1::field}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_default_values.dart:31:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f1a(42, 87); // error
+       ^" in f1a{<inapplicable>}.(42, 87);
+  };
+  dynamic f1b = #C2;
+  dynamic c1c = f1b{dynamic}.call();
+  self::expect(42, c1c{dynamic}.field);
+  dynamic c1d = f1b{dynamic}.call(87);
+  self::expect(87, c1d{dynamic}.field);
+  self::throws(() → dynamic => f1b{dynamic}.call(42, 87));
+  ({field: core::int}) → self::Class2 f2a = #C3;
+  self::Class2 c2a = f2a(){({field: core::int}) → self::Class2};
+  self::expect(42, c2a.{self::Class2::field}{core::int});
+  self::Class2 c2b = f2a(field: 87){({field: core::int}) → self::Class2};
+  self::expect(87, c2b.{self::Class2::field}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_default_values.dart:47:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+    f2a(87); // error
+       ^" in f2a{<inapplicable>}.(87);
+  };
+  dynamic f2b = #C3;
+  dynamic c2c = f2b{dynamic}.call();
+  self::expect(42, c2c{dynamic}.field);
+  dynamic c2d = f2b{dynamic}.call(field: 87);
+  self::expect(87, c2d{dynamic}.field);
+  self::throws(() → dynamic => f2b{dynamic}.call(87));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, {core::bool inSoundModeOnly = #C4}) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print("Thrown: ${e}");
+    return;
+  }
+  if(!self::inSoundMode && inSoundModeOnly) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+constants  {
+  #C1 = 42
+  #C2 = static-tearoff self::Class1::_#new#tearOff
+  #C3 = static-tearoff self::Class2::_#new#tearOff
+  #C4 = false
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_default_values.dart.weak.outline.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_default_values.dart.weak.outline.expect
index 128018d..c630d70 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_default_values.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_default_values.dart.weak.outline.expect
@@ -4,14 +4,14 @@
 
 class Class1 extends core::Object {
   final field core::int field;
-  constructor •([core::int field]) → self::Class1
+  constructor •([core::int field = 42]) → self::Class1
     ;
   static method _#new#tearOff([core::int field]) → self::Class1
     return new self::Class1::•(field);
 }
 class Class2 extends core::Object {
   final field core::int field;
-  constructor •({core::int field}) → self::Class2
+  constructor •({core::int field = 42}) → self::Class2
     ;
   static method _#new#tearOff({core::int field}) → self::Class2
     return new self::Class2::•(field: field);
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_uri.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_uri.dart.weak.modular.expect
new file mode 100644
index 0000000..8666359
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_uri.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_uri_part.dart:8:27: Error: A value of type 'Class Function()' can't be assigned to a variable of type 'Class Function(int)'.
+//  - 'Class' is from 'pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_uri.dart'.
+//   Class Function(int) f = Class.new;
+//                           ^
+//
+import self as self;
+import "dart:core" as core;
+
+part constructor_tear_off_uri_part.dart;
+class Class extends core::Object { // from org-dartlang-testcase:///constructor_tear_off_uri_part.dart
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff() → self::Class
+    return new self::Class::•();
+}
+static method main() → dynamic {}
+static method /* from org-dartlang-testcase:///constructor_tear_off_uri_part.dart */ test() → dynamic {
+  (core::int) → self::Class f = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_uri_part.dart:8:27: Error: A value of type 'Class Function()' can't be assigned to a variable of type 'Class Function(int)'.
+ - 'Class' is from 'pkg/front_end/testcases/constructor_tearoffs/lowering/constructor_tear_off_uri.dart'.
+  Class Function(int) f = Class.new;
+                          ^" in #C1 as{TypeError,ForNonNullableByDefault} (core::int) → self::Class;
+}
+
+constants  {
+  #C1 = static-tearoff self::Class::_#new#tearOff
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/duplicate_typedefs.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/duplicate_typedefs.dart.weak.modular.expect
new file mode 100644
index 0000000..a612cdc
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/duplicate_typedefs.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/duplicate_typedefs.dart:14:9: Error: 'AAlias' is already declared in this scope.
+// typedef AAlias = A; //  error
+//         ^^^^^^
+// pkg/front_end/testcases/constructor_tearoffs/lowering/duplicate_typedefs.dart:11:9: Context: Previous declaration of 'AAlias'.
+// typedef AAlias = A;
+//         ^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/duplicate_typedefs.dart:15:9: Error: 'AAlias' is already declared in this scope.
+// typedef AAlias = C<String>; // error
+//         ^^^^^^
+// pkg/front_end/testcases/constructor_tearoffs/lowering/duplicate_typedefs.dart:14:9: Context: Previous declaration of 'AAlias'.
+// typedef AAlias = A; //  error
+//         ^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/duplicate_typedefs.dart:16:9: Error: 'CAlias' is already declared in this scope.
+// typedef CAlias<T> = C<T>; //  error
+//         ^^^^^^
+// pkg/front_end/testcases/constructor_tearoffs/lowering/duplicate_typedefs.dart:12:9: Context: Previous declaration of 'CAlias'.
+// typedef CAlias<T> = C<T>;
+//         ^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/duplicate_typedefs.dart:17:9: Error: 'CAlias' is already declared in this scope.
+// typedef CAlias = C<String>; //  error
+//         ^^^^^^
+// pkg/front_end/testcases/constructor_tearoffs/lowering/duplicate_typedefs.dart:16:9: Context: Previous declaration of 'CAlias'.
+// typedef CAlias<T> = C<T>; //  error
+//         ^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/duplicate_typedefs.dart:18:9: Error: 'CAlias' is already declared in this scope.
+// typedef CAlias<T1, T2> = C<T1>; //  error
+//         ^^^^^^
+// pkg/front_end/testcases/constructor_tearoffs/lowering/duplicate_typedefs.dart:17:9: Context: Previous declaration of 'CAlias'.
+// typedef CAlias = C<String>; //  error
+//         ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef AAlias = self::A;
+typedef CAlias<T extends core::Object? = dynamic> = self::C<T%>;
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff() → self::A
+    return new self::A::•();
+}
+class C<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::C<self::C::_#new#tearOff::T%>
+    return new self::C::•<self::C::_#new#tearOff::T%>();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..68c70e1
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart.weak.modular.expect
@@ -0,0 +1,254 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:82:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f3a(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:83:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f3a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:98:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f4a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:112:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f5a(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:113:8: Error: Too many positional arguments: 2 allowed, but 3 found.
+// Try removing the extra positional arguments.
+//     f5a(42, 87, 123); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:125:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f6a(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:126:8: Error: Required named parameter 'field3' must be provided.
+//     f6a(42); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:127:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f6a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:128:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f6a(field1: 87, field2: 87); // error
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  constructor _() → self::Class1
+    : super core::Object::•()
+    ;
+  static method _#_#tearOff() → self::Class1
+    return new self::Class1::_();
+  static factory •() → self::Class1
+    return new self::Class1::_();
+  static method _#new#tearOff() → self::Class1
+    return self::Class1::•();
+}
+class Class2 extends core::Object {
+  constructor _() → self::Class2
+    : super core::Object::•()
+    ;
+  static method _#_#tearOff() → self::Class2
+    return new self::Class2::_();
+  static factory named() → self::Class2
+    return new self::Class2::_();
+  static method _#named#tearOff() → self::Class2
+    return self::Class2::named();
+}
+class Class3 extends core::Object {
+  final field core::int field;
+  constructor _(core::int field) → self::Class3
+    : self::Class3::field = field, super core::Object::•()
+    ;
+  static method _#_#tearOff(core::int field) → self::Class3
+    return new self::Class3::_(field);
+  static factory •(core::int field) → self::Class3
+    return new self::Class3::_(field);
+  static method _#new#tearOff(core::int field) → self::Class3
+    return self::Class3::•(field);
+}
+class Class4 extends core::Object {
+  final field core::int? field;
+  constructor _([core::int? field = #C1]) → self::Class4
+    : self::Class4::field = field, super core::Object::•()
+    ;
+  static method _#_#tearOff([core::int? field = #C1]) → self::Class4
+    return new self::Class4::_(field);
+  static factory •([core::int? field = #C1]) → self::Class4
+    return new self::Class4::_(field);
+  static method _#new#tearOff([core::int? field = #C1]) → self::Class4
+    return self::Class4::•(field);
+}
+class Class5 extends core::Object {
+  final field core::int field1;
+  final field core::int? field2;
+  constructor _(core::int field1, [core::int? field2 = #C1]) → self::Class5
+    : self::Class5::field1 = field1, self::Class5::field2 = field2, super core::Object::•()
+    ;
+  static method _#_#tearOff(core::int field1, [core::int? field2 = #C1]) → self::Class5
+    return new self::Class5::_(field1, field2);
+  static factory •(core::int field1, [core::int? field2 = #C1]) → self::Class5
+    return new self::Class5::_(field1, field2);
+  static method _#new#tearOff(core::int field1, [core::int? field2 = #C1]) → self::Class5
+    return self::Class5::•(field1, field2);
+}
+class Class6 extends core::Object {
+  final field core::int field1;
+  final field core::int? field2;
+  final field core::int field3;
+  constructor _(core::int field1, {core::int? field2 = #C1, required core::int field3 = #C1}) → self::Class6
+    : self::Class6::field1 = field1, self::Class6::field2 = field2, self::Class6::field3 = field3, super core::Object::•()
+    ;
+  static method _#_#tearOff(core::int field1, {core::int? field2 = #C1, required core::int field3 = #C1}) → self::Class6
+    return new self::Class6::_(field1, field2: field2, field3: field3);
+  static factory •(core::int field1, {core::int? field2 = #C1, required core::int field3 = #C1}) → self::Class6
+    return new self::Class6::_(field1, field2: field2, field3: field3);
+  static method _#new#tearOff(core::int field1, {core::int? field2 = #C1, required core::int field3 = #C1}) → self::Class6
+    return self::Class6::•(field1, field2: field2, field3: field3);
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static method main() → dynamic {
+  core::print("inSoundMode: ${self::inSoundMode}");
+  self::testNoArgs();
+  self::testArgs();
+}
+static method testNoArgs() → dynamic {
+  () → self::Class1 f1a = #C2;
+  self::Class1 c1a = f1a(){() → self::Class1};
+  self::expect(true, c1a is{ForNonNullableByDefault} self::Class1);
+  dynamic f1b = #C2;
+  dynamic c1b = f1b{dynamic}.call();
+  self::expect(true, c1b is{ForNonNullableByDefault} self::Class1);
+  self::expect(true, core::identical(f1a, f1b));
+  () → self::Class2 f2a = #C3;
+  self::Class2 c2a = f2a(){() → self::Class2};
+  self::expect(true, c2a is{ForNonNullableByDefault} self::Class2);
+  dynamic f2b = #C3;
+  dynamic c2b = f2b{dynamic}.call();
+  self::expect(true, c2b is{ForNonNullableByDefault} self::Class2);
+  self::expect(true, core::identical(f2a, f2b));
+}
+static method testArgs() → dynamic {
+  (core::int) → self::Class3 f3a = #C4;
+  self::Class3 c3a = f3a(42){(core::int) → self::Class3};
+  self::expect(42, c3a.{self::Class3::field}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:82:8: Error: Too few positional arguments: 1 required, 0 given.
+    f3a(); // error
+       ^" in f3a{<inapplicable>}.();
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:83:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f3a(42, 87); // error
+       ^" in f3a{<inapplicable>}.(42, 87);
+  };
+  dynamic f3b = #C4;
+  dynamic c3b = f3b{dynamic}.call(87);
+  self::expect(87, c3b{dynamic}.field);
+  self::throws(() → dynamic => f3b{dynamic}.call());
+  self::throws(() → dynamic => f3b{dynamic}.call(42, 87));
+  ([core::int?]) → self::Class4 f4a = #C5;
+  self::Class4 c4a = f4a(){([core::int?]) → self::Class4};
+  self::expect(null, c4a.{self::Class4::field}{core::int?});
+  self::Class4 c4b = f4a(42){([core::int?]) → self::Class4};
+  self::expect(42, c4b.{self::Class4::field}{core::int?});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:98:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f4a(42, 87); // error
+       ^" in f4a{<inapplicable>}.(42, 87);
+  };
+  dynamic f4b = #C5;
+  self::throws(() → dynamic => f4b{dynamic}.call(42, 87));
+  (core::int, [core::int?]) → self::Class5 f5a = #C6;
+  self::Class5 c5a = f5a(42){(core::int, [core::int?]) → self::Class5};
+  self::expect(42, c5a.{self::Class5::field1}{core::int});
+  self::expect(null, c5a.{self::Class5::field2}{core::int?});
+  self::Class5 c5b = f5a(87, 42){(core::int, [core::int?]) → self::Class5};
+  self::expect(87, c5b.{self::Class5::field1}{core::int});
+  self::expect(42, c5b.{self::Class5::field2}{core::int?});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:112:8: Error: Too few positional arguments: 1 required, 0 given.
+    f5a(); // error
+       ^" in f5a{<inapplicable>}.();
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:113:8: Error: Too many positional arguments: 2 allowed, but 3 found.
+Try removing the extra positional arguments.
+    f5a(42, 87, 123); // error
+       ^" in f5a{<inapplicable>}.(42, 87, 123);
+  };
+  dynamic f5b = #C6;
+  self::throws(() → dynamic => f5b{dynamic}.call());
+  self::throws(() → dynamic => f5b{dynamic}.call(42, 87, 123));
+  (core::int, {field2: core::int?, required field3: core::int}) → self::Class6 f6a = #C7;
+  self::Class6 c6a = f6a(42, field3: 87){(core::int, {field2: core::int?, required field3: core::int}) → self::Class6};
+  self::expect(42, c6a.{self::Class6::field1}{core::int});
+  self::expect(null, c6a.{self::Class6::field2}{core::int?});
+  self::expect(87, c6a.{self::Class6::field3}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:125:8: Error: Too few positional arguments: 1 required, 0 given.
+    f6a(); // error
+       ^" in f6a{<inapplicable>}.();
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:126:8: Error: Required named parameter 'field3' must be provided.
+    f6a(42); // error
+       ^" in f6a{<inapplicable>}.(42);
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:127:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f6a(42, 87); // error
+       ^" in f6a{<inapplicable>}.(42, 87);
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off.dart:128:8: Error: Too few positional arguments: 1 required, 0 given.
+    f6a(field1: 87, field2: 87); // error
+       ^" in f6a{<inapplicable>}.(field1: 87, field2: 87);
+  };
+  self::Class6 c6b = f6a(42, field2: 123, field3: 87){(core::int, {field2: core::int?, required field3: core::int}) → self::Class6};
+  self::expect(42, c6b.{self::Class6::field1}{core::int});
+  self::expect(123, c6b.{self::Class6::field2}{core::int?});
+  self::expect(87, c6b.{self::Class6::field3}{core::int});
+  self::Class6 c6c = f6a(87, field3: 42, field2: 123){(core::int, {field2: core::int?, required field3: core::int}) → self::Class6};
+  self::expect(87, c6c.{self::Class6::field1}{core::int});
+  self::expect(123, c6c.{self::Class6::field2}{core::int?});
+  self::expect(42, c6c.{self::Class6::field3}{core::int});
+  dynamic f6b = #C7;
+  self::throws(() → dynamic => f6b{dynamic}.call());
+  self::throws(() → dynamic => f6b{dynamic}.call(42), inSoundModeOnly: true);
+  self::throws(() → dynamic => f6b{dynamic}.call(42, 87), inSoundModeOnly: true);
+  self::throws(() → dynamic => f6b{dynamic}.call(field1: 87, field2: 87));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, {core::bool inSoundModeOnly = #C8}) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print("Thrown: ${e}");
+    return;
+  }
+  if(!self::inSoundMode && inSoundModeOnly) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+constants  {
+  #C1 = null
+  #C2 = static-tearoff self::Class1::_#new#tearOff
+  #C3 = static-tearoff self::Class2::_#named#tearOff
+  #C4 = static-tearoff self::Class3::_#new#tearOff
+  #C5 = static-tearoff self::Class4::_#new#tearOff
+  #C6 = static-tearoff self::Class5::_#new#tearOff
+  #C7 = static-tearoff self::Class6::_#new#tearOff
+  #C8 = false
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off_default_values.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off_default_values.dart.weak.modular.expect
new file mode 100644
index 0000000..6ef9f15
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off_default_values.dart.weak.modular.expect
@@ -0,0 +1,106 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off_default_values.dart:33:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f1a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off_default_values.dart:49:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//     f2a(87); // error
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  final field core::int field;
+  constructor _(core::int field) → self::Class1
+    : self::Class1::field = field, super core::Object::•()
+    ;
+  static method _#_#tearOff(core::int field) → self::Class1
+    return new self::Class1::_(field);
+  static factory •([core::int field = #C1]) → self::Class1
+    return new self::Class1::_(field);
+  static method _#new#tearOff([core::int field = #C1]) → self::Class1
+    return self::Class1::•(field);
+}
+class Class2 extends core::Object {
+  final field core::int field;
+  constructor _(core::int field) → self::Class2
+    : self::Class2::field = field, super core::Object::•()
+    ;
+  static method _#_#tearOff(core::int field) → self::Class2
+    return new self::Class2::_(field);
+  static factory •({core::int field = #C1}) → self::Class2
+    return new self::Class2::_(field);
+  static method _#new#tearOff({core::int field = #C1}) → self::Class2
+    return self::Class2::•(field: field);
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static method main() → dynamic {
+  core::print("inSoundMode: ${self::inSoundMode}");
+  self::testDefaultValues();
+}
+static method testDefaultValues() → void {
+  ([core::int]) → self::Class1 f1a = #C2;
+  self::Class1 c1a = f1a(){([core::int]) → self::Class1};
+  self::expect(42, c1a.{self::Class1::field}{core::int});
+  self::Class1 c1b = f1a(87){([core::int]) → self::Class1};
+  self::expect(87, c1b.{self::Class1::field}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off_default_values.dart:33:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f1a(42, 87); // error
+       ^" in f1a{<inapplicable>}.(42, 87);
+  };
+  dynamic f1b = #C2;
+  dynamic c1c = f1b{dynamic}.call();
+  self::expect(42, c1c{dynamic}.field);
+  dynamic c1d = f1b{dynamic}.call(87);
+  self::expect(87, c1d{dynamic}.field);
+  self::throws(() → dynamic => f1b{dynamic}.call(42, 87));
+  ({field: core::int}) → self::Class2 f2a = #C3;
+  self::Class2 c2a = f2a(){({field: core::int}) → self::Class2};
+  self::expect(42, c2a.{self::Class2::field}{core::int});
+  self::Class2 c2b = f2a(field: 87){({field: core::int}) → self::Class2};
+  self::expect(87, c2b.{self::Class2::field}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/factory_tear_off_default_values.dart:49:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+    f2a(87); // error
+       ^" in f2a{<inapplicable>}.(87);
+  };
+  dynamic f2b = #C3;
+  dynamic c2c = f2b{dynamic}.call();
+  self::expect(42, c2c{dynamic}.field);
+  dynamic c2d = f2b{dynamic}.call(field: 87);
+  self::expect(87, c2d{dynamic}.field);
+  self::throws(() → dynamic => f2b{dynamic}.call(87));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, {core::bool inSoundModeOnly = #C4}) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print("Thrown: ${e}");
+    return;
+  }
+  if(!self::inSoundMode && inSoundModeOnly) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+constants  {
+  #C1 = 42
+  #C2 = static-tearoff self::Class1::_#new#tearOff
+  #C3 = static-tearoff self::Class2::_#new#tearOff
+  #C4 = false
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart.weak.modular.expect
new file mode 100644
index 0000000..c83f268
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart.weak.modular.expect
@@ -0,0 +1,187 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart:44:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f3a(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart:45:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f3a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart:62:8: Error: Expected 1 type arguments.
+//     f4a<int, String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart:70:8: Error: Expected 0 type arguments.
+//     f4b<int>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart:87:8: Error: Expected 1 type arguments.
+//     f4d<int, String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart:95:8: Error: Expected 0 type arguments.
+//     f4e<int>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart:112:8: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'call'.
+// Try changing type arguments so that they conform to the bounds.
+//     f5a<String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart:113:8: Error: Expected 1 type arguments.
+//     f5a<int, String>(); // error
+//        ^
+//
+import self as self;
+import "main_lib.dart" as mai;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static method main() → dynamic {
+  () → mai::Class1 f1a = #C1;
+  mai::Class1 c1a = f1a(){() → mai::Class1};
+  self::expect(true, c1a is{ForNonNullableByDefault} mai::Class1);
+  dynamic f1b = #C1;
+  dynamic c1b = f1b{dynamic}.call();
+  self::expect(true, c1b is{ForNonNullableByDefault} mai::Class1);
+  self::expect(true, core::identical(f1a, f1b));
+  () → mai::Class2 f2a = #C2;
+  mai::Class2 c2a = f2a(){() → mai::Class2};
+  self::expect(true, c2a is{ForNonNullableByDefault} mai::Class2);
+  dynamic f2b = #C2;
+  dynamic c2b = f2b{dynamic}.call();
+  self::expect(true, c2b is{ForNonNullableByDefault} mai::Class2);
+  self::expect(true, core::identical(f2a, f2b));
+  () → mai::Class2 f2c = #C3;
+  mai::Class2 c2c = f2c(){() → mai::Class2};
+  self::expect(true, c2c is{ForNonNullableByDefault} mai::Class2);
+  dynamic f2d = #C3;
+  dynamic c2d = f2d{dynamic}.call();
+  self::expect(true, c2d is{ForNonNullableByDefault} mai::Class2);
+  self::expect(true, core::identical(f2c, f2d));
+  (core::int) → mai::Class3 f3a = #C4;
+  mai::Class3 c3a = f3a(42){(core::int) → mai::Class3};
+  self::expect(42, c3a.{mai::Class3::field}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart:44:8: Error: Too few positional arguments: 1 required, 0 given.
+    f3a(); // error
+       ^" in f3a{<inapplicable>}.();
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart:45:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f3a(42, 87); // error
+       ^" in f3a{<inapplicable>}.(42, 87);
+  };
+  dynamic f3b = #C4;
+  dynamic c3b = f3b{dynamic}.call(87);
+  self::expect(87, c3b{dynamic}.field);
+  self::throws(() → dynamic => f3b{dynamic}.call());
+  self::throws(() → dynamic => f3b{dynamic}.call(42, 87));
+  <T extends core::Object? = dynamic>() → mai::Class4<T%> f4a = #C5;
+  mai::Class4<dynamic> c4a = f4a<dynamic>(){() → mai::Class4<dynamic>};
+  self::expect(true, c4a is{ForNonNullableByDefault} mai::Class4<dynamic>);
+  self::expect(false, c4a is{ForNonNullableByDefault} mai::Class4<core::int>);
+  mai::Class4<core::int> c4b = f4a<core::int>(){() → mai::Class4<core::int>};
+  self::expect(true, c4b is{ForNonNullableByDefault} mai::Class4<core::int>);
+  self::expect(false, c4b is{ForNonNullableByDefault} mai::Class4<core::String>);
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart:62:8: Error: Expected 1 type arguments.
+    f4a<int, String>(); // error
+       ^" in f4a{<inapplicable>}.<core::int, core::String>();
+  };
+  () → mai::Class4<core::int> f4b = f4a<core::int>;
+  mai::Class4<core::int> c4c = f4b(){() → mai::Class4<core::int>};
+  self::expect(true, c4c is{ForNonNullableByDefault} mai::Class4<core::int>);
+  self::expect(false, c4c is{ForNonNullableByDefault} mai::Class4<core::String>);
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart:70:8: Error: Expected 0 type arguments.
+    f4b<int>(); // error
+       ^" in f4b{<inapplicable>}.<core::int>();
+  };
+  dynamic f4c = #C5;
+  dynamic c4d = f4c{dynamic}.call();
+  self::expect(true, c4d is{ForNonNullableByDefault} mai::Class4<dynamic>);
+  self::expect(false, c4d is{ForNonNullableByDefault} mai::Class4<core::int>);
+  self::throws(() → dynamic => f4c{dynamic}.call<core::int, core::String>());
+  <T extends core::Object? = dynamic>() → mai::Class4<T%> f4d = #C6;
+  mai::Class4<dynamic> c4e = f4d<dynamic>(){() → mai::Class4<dynamic>};
+  self::expect(true, c4e is{ForNonNullableByDefault} mai::Class4<dynamic>);
+  self::expect(false, c4e is{ForNonNullableByDefault} mai::Class4<core::int>);
+  mai::Class4<core::int> c4f = f4d<core::int>(){() → mai::Class4<core::int>};
+  self::expect(true, c4f is{ForNonNullableByDefault} mai::Class4<core::int>);
+  self::expect(false, c4f is{ForNonNullableByDefault} mai::Class4<core::String>);
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart:87:8: Error: Expected 1 type arguments.
+    f4d<int, String>(); // error
+       ^" in f4d{<inapplicable>}.<core::int, core::String>();
+  };
+  () → mai::Class4<core::int> f4e = f4d<core::int>;
+  mai::Class4<core::int> c4g = f4e(){() → mai::Class4<core::int>};
+  self::expect(true, c4g is{ForNonNullableByDefault} mai::Class4<core::int>);
+  self::expect(false, c4g is{ForNonNullableByDefault} mai::Class4<core::String>);
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart:95:8: Error: Expected 0 type arguments.
+    f4e<int>(); // error
+       ^" in f4e{<inapplicable>}.<core::int>();
+  };
+  dynamic f4f = #C6;
+  dynamic c4h = f4f{dynamic}.call();
+  self::expect(true, c4h is{ForNonNullableByDefault} mai::Class4<dynamic>);
+  self::expect(false, c4h is{ForNonNullableByDefault} mai::Class4<core::int>);
+  self::throws(() → dynamic => f4f{dynamic}.call<core::int, core::String>());
+  <T extends core::num>() → mai::Class5<T> f5a = #C7;
+  mai::Class5<core::num> c5a = f5a<core::num>(){() → mai::Class5<core::num>};
+  self::expect(true, c5a is{ForNonNullableByDefault} mai::Class5<core::num>);
+  self::expect(false, c5a is{ForNonNullableByDefault} mai::Class5<core::int>);
+  mai::Class5<core::int> c5b = f5a<core::int>(){() → mai::Class5<core::int>};
+  self::expect(true, c5b is{ForNonNullableByDefault} mai::Class5<core::int>);
+  self::expect(false, c5b is{ForNonNullableByDefault} mai::Class5<core::double>);
+  () → Null {
+    f5a<core::String>(){() → mai::Class5<core::String>};
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/from_dill/main.dart:113:8: Error: Expected 1 type arguments.
+    f5a<int, String>(); // error
+       ^" in f5a{<inapplicable>}.<core::int, core::String>();
+  };
+  dynamic f5b = #C7;
+  dynamic c5c = f5b{dynamic}.call();
+  self::expect(true, c5c is{ForNonNullableByDefault} mai::Class5<core::num>);
+  self::expect(false, c5c is{ForNonNullableByDefault} mai::Class5<core::int>);
+  dynamic c5d = f5b{dynamic}.call<core::int>();
+  self::expect(true, c5d is{ForNonNullableByDefault} mai::Class5<core::int>);
+  self::expect(false, c5d is{ForNonNullableByDefault} mai::Class5<core::double>);
+  self::throws(() → dynamic => f5b{dynamic}.call<core::String>());
+  self::throws(() → dynamic => f5b{dynamic}.call<core::int, core::String>());
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, {core::bool inSoundModeOnly = #C8}) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print("Thrown: ${e}");
+    return;
+  }
+  if(!self::inSoundMode && inSoundModeOnly) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+constants  {
+  #C1 = static-tearoff mai::Class1::_#new#tearOff
+  #C2 = static-tearoff mai::Class2::_#named#tearOff
+  #C3 = static-tearoff mai::Class2::_#redirect#tearOff
+  #C4 = static-tearoff mai::Class3::_#new#tearOff
+  #C5 = static-tearoff mai::Class4::_#new#tearOff
+  #C6 = static-tearoff mai::Class4::_#redirect#tearOff
+  #C7 = static-tearoff mai::Class5::_#new#tearOff
+  #C8 = false
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/generic_constructor_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/generic_constructor_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..7cca76e
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/generic_constructor_tear_off.dart.weak.modular.expect
@@ -0,0 +1,180 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_constructor_tear_off.dart:24:8: Error: Expected 1 type arguments.
+//     f1a<int, String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_constructor_tear_off.dart:32:8: Error: Expected 0 type arguments.
+//     f1b<int>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_constructor_tear_off.dart:59:8: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'call'.
+// Try changing type arguments so that they conform to the bounds.
+//     f2a<String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_constructor_tear_off.dart:60:8: Error: Expected 1 type arguments.
+//     f2a<int, String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_constructor_tear_off.dart:81:8: Error: Type argument 'num' doesn't conform to the bound 'S' of the type variable 'T' on 'call'.
+// Try changing type arguments so that they conform to the bounds.
+//     f3a<num, int>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_constructor_tear_off.dart:95:18: Error: Inferred type argument 'Class4<Object?>' doesn't conform to the bound 'Class4<T>' of the type variable 'T' on 'call'.
+//  - 'Class4' is from 'pkg/front_end/testcases/constructor_tearoffs/lowering/generic_constructor_tear_off.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     var c4a = f4a(); // error
+//                  ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Class1<self::Class1::T%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::Class1<self::Class1::_#new#tearOff::T%>
+    return new self::Class1::•<self::Class1::_#new#tearOff::T%>();
+}
+class Class2<T extends core::num> extends core::Object {
+  synthetic constructor •() → self::Class2<self::Class2::T>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::num>() → self::Class2<self::Class2::_#new#tearOff::T>
+    return new self::Class2::•<self::Class2::_#new#tearOff::T>();
+}
+class Class3<T extends self::Class3::S% = dynamic, S extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Class3<self::Class3::T%, self::Class3::S%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends self::Class3::_#new#tearOff::S% = dynamic, S extends core::Object? = dynamic>() → self::Class3<self::Class3::_#new#tearOff::T%, self::Class3::_#new#tearOff::S%>
+    return new self::Class3::•<self::Class3::_#new#tearOff::T%, self::Class3::_#new#tearOff::S%>();
+}
+class Class4<T extends self::Class4<self::Class4::T> = self::Class4<dynamic>> extends core::Object {
+  synthetic constructor •() → self::Class4<self::Class4::T>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends self::Class4<self::Class4::_#new#tearOff::T> = self::Class4<dynamic>>() → self::Class4<self::Class4::_#new#tearOff::T>
+    return new self::Class4::•<self::Class4::_#new#tearOff::T>();
+}
+class Class4int extends self::Class4<self::Class4int> {
+  synthetic constructor •() → self::Class4int
+    : super self::Class4::•()
+    ;
+  static method _#new#tearOff() → self::Class4int
+    return new self::Class4int::•();
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static method main() → dynamic {
+  core::print("inSoundMode: ${self::inSoundMode}");
+  self::testGeneric();
+  self::testBounded();
+}
+static method testGeneric() → dynamic {
+  <T extends core::Object? = dynamic>() → self::Class1<T%> f1a = #C1;
+  self::Class1<dynamic> c1a = f1a<dynamic>(){() → self::Class1<dynamic>};
+  self::expect(true, c1a is{ForNonNullableByDefault} self::Class1<dynamic>);
+  self::expect(false, c1a is{ForNonNullableByDefault} self::Class1<core::int>);
+  self::Class1<core::int> c1b = f1a<core::int>(){() → self::Class1<core::int>};
+  self::expect(true, c1b is{ForNonNullableByDefault} self::Class1<core::int>);
+  self::expect(false, c1b is{ForNonNullableByDefault} self::Class1<core::String>);
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/generic_constructor_tear_off.dart:24:8: Error: Expected 1 type arguments.
+    f1a<int, String>(); // error
+       ^" in f1a{<inapplicable>}.<core::int, core::String>();
+  };
+  () → self::Class1<core::int> f1b = f1a<core::int>;
+  self::Class1<core::int> c1c = f1b(){() → self::Class1<core::int>};
+  self::expect(true, c1c is{ForNonNullableByDefault} self::Class1<core::int>);
+  self::expect(false, c1c is{ForNonNullableByDefault} self::Class1<core::String>);
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/generic_constructor_tear_off.dart:32:8: Error: Expected 0 type arguments.
+    f1b<int>(); // error
+       ^" in f1b{<inapplicable>}.<core::int>();
+  };
+  dynamic f1c = #C1;
+  dynamic c1d = f1c{dynamic}.call();
+  self::expect(true, c1a is{ForNonNullableByDefault} self::Class1<dynamic>);
+  self::expect(false, c1a is{ForNonNullableByDefault} self::Class1<core::int>);
+  self::throws(() → dynamic => f1c{dynamic}.call<core::int, core::String>());
+}
+static method testBounded() → dynamic {
+  <T extends core::num>() → self::Class2<T> f2a = #C2;
+  self::Class2<core::num> c2a = f2a<core::num>(){() → self::Class2<core::num>};
+  self::expect(true, c2a is{ForNonNullableByDefault} self::Class2<core::num>);
+  self::expect(false, c2a is{ForNonNullableByDefault} self::Class2<core::int>);
+  self::Class2<core::int> c2b = f2a<core::int>(){() → self::Class2<core::int>};
+  self::expect(true, c2b is{ForNonNullableByDefault} self::Class2<core::int>);
+  self::expect(false, c2b is{ForNonNullableByDefault} self::Class2<core::double>);
+  () → Null {
+    f2a<core::String>(){() → self::Class2<core::String>};
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/generic_constructor_tear_off.dart:60:8: Error: Expected 1 type arguments.
+    f2a<int, String>(); // error
+       ^" in f2a{<inapplicable>}.<core::int, core::String>();
+  };
+  dynamic f2b = #C2;
+  dynamic c2c = f2b{dynamic}.call();
+  self::expect(true, c2c is{ForNonNullableByDefault} self::Class2<core::num>);
+  self::expect(false, c2c is{ForNonNullableByDefault} self::Class2<core::int>);
+  dynamic c2d = f2b{dynamic}.call<core::int>();
+  self::expect(true, c2d is{ForNonNullableByDefault} self::Class2<core::int>);
+  self::expect(false, c2d is{ForNonNullableByDefault} self::Class2<core::double>);
+  self::throws(() → dynamic => f2b{dynamic}.call<core::String>());
+  self::throws(() → dynamic => f2b{dynamic}.call<core::int, core::String>());
+  <T extends S% = dynamic, S extends core::Object? = dynamic>() → self::Class3<T%, S%> f3a = #C3;
+  self::Class3<dynamic, dynamic> c3a = f3a<dynamic, dynamic>(){() → self::Class3<dynamic, dynamic>};
+  self::expect(true, c3a is{ForNonNullableByDefault} self::Class3<dynamic, dynamic>);
+  self::expect(false, c3a is{ForNonNullableByDefault} self::Class3<core::int, core::num>);
+  self::Class3<core::int, core::num> c3b = f3a<core::int, core::num>(){() → self::Class3<core::int, core::num>};
+  self::expect(true, c3b is{ForNonNullableByDefault} self::Class3<core::int, core::num>);
+  self::expect(false, c3b is{ForNonNullableByDefault} self::Class3<core::double, core::num>);
+  () → Null {
+    f3a<core::num, core::int>(){() → self::Class3<core::num, core::int>};
+  };
+  dynamic f3b = #C3;
+  dynamic c3c = f3b{dynamic}.call();
+  self::expect(true, c3c is{ForNonNullableByDefault} self::Class3<dynamic, dynamic>);
+  self::expect(false, c3c is{ForNonNullableByDefault} self::Class3<core::int, core::num>);
+  dynamic c3d = f3b{dynamic}.call<core::int, core::num>();
+  self::expect(true, c3d is{ForNonNullableByDefault} self::Class3<core::int, core::num>);
+  self::expect(false, c3d is{ForNonNullableByDefault} self::Class3<core::double, core::num>);
+  self::throws(() → dynamic => f3b{dynamic}.call<core::num, core::int>());
+  <T extends self::Class4<T> = self::Class4<dynamic>>() → self::Class4<T> f4a = #C4;
+  () → Null {
+    self::Class4<self::Class4<core::Object?>> c4a = f4a<self::Class4<core::Object?>>(){() → self::Class4<self::Class4<core::Object?>>};
+  };
+  dynamic f4b = #C4;
+  self::throws(() → dynamic => f4b{dynamic}.call());
+  dynamic c4b = f4b{dynamic}.call<self::Class4int>();
+  self::expect(true, c4b is{ForNonNullableByDefault} self::Class4<self::Class4int>);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, {core::bool inSoundModeOnly = #C5}) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print("Thrown: ${e}");
+    return;
+  }
+  if(!self::inSoundMode && inSoundModeOnly) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+constants  {
+  #C1 = static-tearoff self::Class1::_#new#tearOff
+  #C2 = static-tearoff self::Class2::_#new#tearOff
+  #C3 = static-tearoff self::Class3::_#new#tearOff
+  #C4 = static-tearoff self::Class4::_#new#tearOff
+  #C5 = false
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/generic_factory_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/generic_factory_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..2addbc7
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/generic_factory_tear_off.dart.weak.modular.expect
@@ -0,0 +1,200 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_factory_tear_off.dart:27:8: Error: Expected 1 type arguments.
+//     f1a<int, String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_factory_tear_off.dart:35:8: Error: Expected 0 type arguments.
+//     f1b<int>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_factory_tear_off.dart:74:8: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'call'.
+// Try changing type arguments so that they conform to the bounds.
+//     f2a<String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_factory_tear_off.dart:75:8: Error: Expected 1 type arguments.
+//     f2a<int, String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_factory_tear_off.dart:96:8: Error: Type argument 'num' doesn't conform to the bound 'S' of the type variable 'T' on 'call'.
+// Try changing type arguments so that they conform to the bounds.
+//     f3a<num, int>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_factory_tear_off.dart:110:18: Error: Inferred type argument 'Class4<Object?>' doesn't conform to the bound 'Class4<T>' of the type variable 'T' on 'call'.
+//  - 'Class4' is from 'pkg/front_end/testcases/constructor_tearoffs/lowering/generic_factory_tear_off.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     var c4a = f4a(); // error
+//                  ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1<T extends core::Object? = dynamic> extends core::Object {
+  constructor _() → self::Class1<self::Class1::T%>
+    : super core::Object::•()
+    ;
+  static method _#_#tearOff<T extends core::Object? = dynamic>() → self::Class1<self::Class1::_#_#tearOff::T%>
+    return new self::Class1::_<self::Class1::_#_#tearOff::T%>();
+  static factory •<T extends core::Object? = dynamic>() → self::Class1<self::Class1::•::T%>
+    return new self::Class1::_<self::Class1::•::T%>();
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::Class1<self::Class1::_#new#tearOff::T%>
+    return self::Class1::•<self::Class1::_#new#tearOff::T%>();
+}
+class Class2<T extends core::num> extends core::Object {
+  constructor _() → self::Class2<self::Class2::T>
+    : super core::Object::•()
+    ;
+  static method _#_#tearOff<T extends core::num>() → self::Class2<self::Class2::_#_#tearOff::T>
+    return new self::Class2::_<self::Class2::_#_#tearOff::T>();
+  static factory •<T extends core::num>() → self::Class2<self::Class2::•::T>
+    return new self::Class2::_<self::Class2::•::T>();
+  static method _#new#tearOff<T extends core::num>() → self::Class2<self::Class2::_#new#tearOff::T>
+    return self::Class2::•<self::Class2::_#new#tearOff::T>();
+}
+class Class3<T extends self::Class3::S% = dynamic, S extends core::Object? = dynamic> extends core::Object {
+  constructor _() → self::Class3<self::Class3::T%, self::Class3::S%>
+    : super core::Object::•()
+    ;
+  static method _#_#tearOff<T extends self::Class3::_#_#tearOff::S% = dynamic, S extends core::Object? = dynamic>() → self::Class3<self::Class3::_#_#tearOff::T%, self::Class3::_#_#tearOff::S%>
+    return new self::Class3::_<self::Class3::_#_#tearOff::T%, self::Class3::_#_#tearOff::S%>();
+  static factory •<T extends self::Class3::•::S% = dynamic, S extends core::Object? = dynamic>() → self::Class3<self::Class3::•::T%, self::Class3::•::S%>
+    return new self::Class3::_<self::Class3::•::T%, self::Class3::•::S%>();
+  static method _#new#tearOff<T extends self::Class3::_#new#tearOff::S% = dynamic, S extends core::Object? = dynamic>() → self::Class3<self::Class3::_#new#tearOff::T%, self::Class3::_#new#tearOff::S%>
+    return self::Class3::•<self::Class3::_#new#tearOff::T%, self::Class3::_#new#tearOff::S%>();
+}
+class Class4<T extends self::Class4<self::Class4::T> = self::Class4<dynamic>> extends core::Object {
+  constructor _() → self::Class4<self::Class4::T>
+    : super core::Object::•()
+    ;
+  static method _#_#tearOff<T extends self::Class4<self::Class4::_#_#tearOff::T> = self::Class4<dynamic>>() → self::Class4<self::Class4::_#_#tearOff::T>
+    return new self::Class4::_<self::Class4::_#_#tearOff::T>();
+  static factory •<T extends self::Class4<self::Class4::•::T> = self::Class4<dynamic>>() → self::Class4<self::Class4::•::T>
+    return new self::Class4::_<self::Class4::•::T>();
+  static method _#new#tearOff<T extends self::Class4<self::Class4::_#new#tearOff::T> = self::Class4<dynamic>>() → self::Class4<self::Class4::_#new#tearOff::T>
+    return self::Class4::•<self::Class4::_#new#tearOff::T>();
+}
+class Class4int extends self::Class4<self::Class4int> {
+  constructor _() → self::Class4int
+    : super self::Class4::_()
+    ;
+  static method _#_#tearOff() → self::Class4int
+    return new self::Class4int::_();
+  static factory •() → self::Class4int
+    return new self::Class4int::_();
+  static method _#new#tearOff() → self::Class4int
+    return self::Class4int::•();
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static method main() → dynamic {
+  core::print("inSoundMode: ${self::inSoundMode}");
+  self::testGeneric();
+  self::testBounded();
+}
+static method testGeneric() → dynamic {
+  <T extends core::Object? = dynamic>() → self::Class1<T%> f1a = #C1;
+  self::Class1<dynamic> c1a = f1a<dynamic>(){() → self::Class1<dynamic>};
+  self::expect(true, c1a is{ForNonNullableByDefault} self::Class1<dynamic>);
+  self::expect(false, c1a is{ForNonNullableByDefault} self::Class1<core::int>);
+  self::Class1<core::int> c1b = f1a<core::int>(){() → self::Class1<core::int>};
+  self::expect(true, c1b is{ForNonNullableByDefault} self::Class1<core::int>);
+  self::expect(false, c1b is{ForNonNullableByDefault} self::Class1<core::String>);
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/generic_factory_tear_off.dart:27:8: Error: Expected 1 type arguments.
+    f1a<int, String>(); // error
+       ^" in f1a{<inapplicable>}.<core::int, core::String>();
+  };
+  () → self::Class1<core::int> f1b = f1a<core::int>;
+  self::Class1<core::int> c1c = f1b(){() → self::Class1<core::int>};
+  self::expect(true, c1c is{ForNonNullableByDefault} self::Class1<core::int>);
+  self::expect(false, c1c is{ForNonNullableByDefault} self::Class1<core::String>);
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/generic_factory_tear_off.dart:35:8: Error: Expected 0 type arguments.
+    f1b<int>(); // error
+       ^" in f1b{<inapplicable>}.<core::int>();
+  };
+  dynamic f1c = #C1;
+  dynamic c1d = f1c{dynamic}.call();
+  self::expect(true, c1a is{ForNonNullableByDefault} self::Class1<dynamic>);
+  self::expect(false, c1a is{ForNonNullableByDefault} self::Class1<core::int>);
+  self::throws(() → dynamic => f1c{dynamic}.call<core::int, core::String>());
+}
+static method testBounded() → dynamic {
+  <T extends core::num>() → self::Class2<T> f2a = #C2;
+  self::Class2<core::num> c2a = f2a<core::num>(){() → self::Class2<core::num>};
+  self::expect(true, c2a is{ForNonNullableByDefault} self::Class2<core::num>);
+  self::expect(false, c2a is{ForNonNullableByDefault} self::Class2<core::int>);
+  self::Class2<core::int> c2b = f2a<core::int>(){() → self::Class2<core::int>};
+  self::expect(true, c2b is{ForNonNullableByDefault} self::Class2<core::int>);
+  self::expect(false, c2b is{ForNonNullableByDefault} self::Class2<core::double>);
+  () → Null {
+    f2a<core::String>(){() → self::Class2<core::String>};
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/generic_factory_tear_off.dart:75:8: Error: Expected 1 type arguments.
+    f2a<int, String>(); // error
+       ^" in f2a{<inapplicable>}.<core::int, core::String>();
+  };
+  dynamic f2b = #C2;
+  dynamic c2c = f2b{dynamic}.call();
+  self::expect(true, c2c is{ForNonNullableByDefault} self::Class2<core::num>);
+  self::expect(false, c2c is{ForNonNullableByDefault} self::Class2<core::int>);
+  dynamic c2d = f2b{dynamic}.call<core::int>();
+  self::expect(true, c2d is{ForNonNullableByDefault} self::Class2<core::int>);
+  self::expect(false, c2d is{ForNonNullableByDefault} self::Class2<core::double>);
+  self::throws(() → dynamic => f2b{dynamic}.call<core::String>());
+  self::throws(() → dynamic => f2b{dynamic}.call<core::int, core::String>());
+  <T extends S% = dynamic, S extends core::Object? = dynamic>() → self::Class3<T%, S%> f3a = #C3;
+  self::Class3<dynamic, dynamic> c3a = f3a<dynamic, dynamic>(){() → self::Class3<dynamic, dynamic>};
+  self::expect(true, c3a is{ForNonNullableByDefault} self::Class3<dynamic, dynamic>);
+  self::expect(false, c3a is{ForNonNullableByDefault} self::Class3<core::int, core::num>);
+  self::Class3<core::int, core::num> c3b = f3a<core::int, core::num>(){() → self::Class3<core::int, core::num>};
+  self::expect(true, c3b is{ForNonNullableByDefault} self::Class3<core::int, core::num>);
+  self::expect(false, c3b is{ForNonNullableByDefault} self::Class3<core::double, core::num>);
+  () → Null {
+    f3a<core::num, core::int>(){() → self::Class3<core::num, core::int>};
+  };
+  dynamic f3b = #C3;
+  dynamic c3c = f3b{dynamic}.call();
+  self::expect(true, c3c is{ForNonNullableByDefault} self::Class3<dynamic, dynamic>);
+  self::expect(false, c3c is{ForNonNullableByDefault} self::Class3<core::int, core::num>);
+  dynamic c3d = f3b{dynamic}.call<core::int, core::num>();
+  self::expect(true, c3d is{ForNonNullableByDefault} self::Class3<core::int, core::num>);
+  self::expect(false, c3d is{ForNonNullableByDefault} self::Class3<core::double, core::num>);
+  self::throws(() → dynamic => f3b{dynamic}.call<core::num, core::int>());
+  <T extends self::Class4<T> = self::Class4<dynamic>>() → self::Class4<T> f4a = #C4;
+  () → Null {
+    self::Class4<self::Class4<core::Object?>> c4a = f4a<self::Class4<core::Object?>>(){() → self::Class4<self::Class4<core::Object?>>};
+  };
+  dynamic f4b = #C4;
+  self::throws(() → dynamic => f4b{dynamic}.call());
+  dynamic c4b = f4b{dynamic}.call<self::Class4int>();
+  self::expect(true, c4b is{ForNonNullableByDefault} self::Class4<self::Class4int>);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, {core::bool inSoundModeOnly = #C5}) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print("Thrown: ${e}");
+    return;
+  }
+  if(!self::inSoundMode && inSoundModeOnly) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+constants  {
+  #C1 = static-tearoff self::Class1::_#new#tearOff
+  #C2 = static-tearoff self::Class2::_#new#tearOff
+  #C3 = static-tearoff self::Class3::_#new#tearOff
+  #C4 = static-tearoff self::Class4::_#new#tearOff
+  #C5 = false
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/generic_redirecting_factory_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/generic_redirecting_factory_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..81c7cd2
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/generic_redirecting_factory_tear_off.dart.weak.modular.expect
@@ -0,0 +1,210 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_redirecting_factory_tear_off.dart:27:8: Error: Expected 1 type arguments.
+//     f1a<int, String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_redirecting_factory_tear_off.dart:35:8: Error: Expected 0 type arguments.
+//     f1b<int>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_redirecting_factory_tear_off.dart:74:8: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'call'.
+// Try changing type arguments so that they conform to the bounds.
+//     f2a<String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_redirecting_factory_tear_off.dart:75:8: Error: Expected 1 type arguments.
+//     f2a<int, String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_redirecting_factory_tear_off.dart:96:8: Error: Type argument 'num' doesn't conform to the bound 'S' of the type variable 'T' on 'call'.
+// Try changing type arguments so that they conform to the bounds.
+//     f3a<num, int>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/generic_redirecting_factory_tear_off.dart:110:18: Error: Inferred type argument 'Class4<Object?>' doesn't conform to the bound 'Class4<T>' of the type variable 'T' on 'call'.
+//  - 'Class4' is from 'pkg/front_end/testcases/constructor_tearoffs/lowering/generic_redirecting_factory_tear_off.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     var c4a = f4a(); // error
+//                  ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1<T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor _() → self::Class1<self::Class1::T%>
+    : super core::Object::•()
+    ;
+  static method _#_#tearOff<T extends core::Object? = dynamic>() → self::Class1<self::Class1::_#_#tearOff::T%>
+    return new self::Class1::_<self::Class1::_#_#tearOff::T%>();
+  static factory •<T extends core::Object? = dynamic>() → self::Class1<self::Class1::•::T%>
+    return new self::Class1::_<self::Class1::•::T%>();
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::Class1<self::Class1::_#new#tearOff::T%>
+    return new self::Class1::_<self::Class1::_#new#tearOff::T%>();
+}
+class Class2<T extends core::num> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C2]/*isLegacy*/;
+  constructor _() → self::Class2<self::Class2::T>
+    : super core::Object::•()
+    ;
+  static method _#_#tearOff<T extends core::num>() → self::Class2<self::Class2::_#_#tearOff::T>
+    return new self::Class2::_<self::Class2::_#_#tearOff::T>();
+  static factory •<T extends core::num>() → self::Class2<self::Class2::•::T>
+    return new self::Class2::_<self::Class2::•::T>();
+  static method _#new#tearOff<T extends core::num>() → self::Class2<self::Class2::_#new#tearOff::T>
+    return new self::Class2::_<self::Class2::_#new#tearOff::T>();
+}
+class Class3<T extends self::Class3::S% = dynamic, S extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C3]/*isLegacy*/;
+  constructor _() → self::Class3<self::Class3::T%, self::Class3::S%>
+    : super core::Object::•()
+    ;
+  static method _#_#tearOff<T extends self::Class3::_#_#tearOff::S% = dynamic, S extends core::Object? = dynamic>() → self::Class3<self::Class3::_#_#tearOff::T%, self::Class3::_#_#tearOff::S%>
+    return new self::Class3::_<self::Class3::_#_#tearOff::T%, self::Class3::_#_#tearOff::S%>();
+  static factory •<T extends self::Class3::•::S% = dynamic, S extends core::Object? = dynamic>() → self::Class3<self::Class3::•::T%, self::Class3::•::S%>
+    return new self::Class3::_<self::Class3::•::T%, self::Class3::•::S%>();
+  static method _#new#tearOff<T extends self::Class3::_#new#tearOff::S% = dynamic, S extends core::Object? = dynamic>() → self::Class3<self::Class3::_#new#tearOff::T%, self::Class3::_#new#tearOff::S%>
+    return new self::Class3::_<self::Class3::_#new#tearOff::T%, self::Class3::_#new#tearOff::S%>();
+}
+class Class4<T extends self::Class4<self::Class4::T> = self::Class4<dynamic>> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C4]/*isLegacy*/;
+  constructor _() → self::Class4<self::Class4::T>
+    : super core::Object::•()
+    ;
+  static method _#_#tearOff<T extends self::Class4<self::Class4::_#_#tearOff::T> = self::Class4<dynamic>>() → self::Class4<self::Class4::_#_#tearOff::T>
+    return new self::Class4::_<self::Class4::_#_#tearOff::T>();
+  static factory •<T extends self::Class4<self::Class4::•::T> = self::Class4<dynamic>>() → self::Class4<self::Class4::•::T>
+    return new self::Class4::_<self::Class4::•::T>();
+  static method _#new#tearOff<T extends self::Class4<self::Class4::_#new#tearOff::T> = self::Class4<dynamic>>() → self::Class4<self::Class4::_#new#tearOff::T>
+    return new self::Class4::_<self::Class4::_#new#tearOff::T>();
+}
+class Class4int extends self::Class4<self::Class4int> {
+  static final field dynamic _redirecting# = <dynamic>[#C5]/*isLegacy*/;
+  constructor _() → self::Class4int
+    : super self::Class4::_()
+    ;
+  static method _#_#tearOff() → self::Class4int
+    return new self::Class4int::_();
+  static factory •() → self::Class4int
+    return new self::Class4int::_();
+  static method _#new#tearOff() → self::Class4int
+    return new self::Class4int::_();
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static method main() → dynamic {
+  core::print("inSoundMode: ${self::inSoundMode}");
+  self::testGeneric();
+  self::testBounded();
+}
+static method testGeneric() → dynamic {
+  <T extends core::Object? = dynamic>() → self::Class1<T%> f1a = #C6;
+  self::Class1<dynamic> c1a = f1a<dynamic>(){() → self::Class1<dynamic>};
+  self::expect(true, c1a is{ForNonNullableByDefault} self::Class1<dynamic>);
+  self::expect(false, c1a is{ForNonNullableByDefault} self::Class1<core::int>);
+  self::Class1<core::int> c1b = f1a<core::int>(){() → self::Class1<core::int>};
+  self::expect(true, c1b is{ForNonNullableByDefault} self::Class1<core::int>);
+  self::expect(false, c1b is{ForNonNullableByDefault} self::Class1<core::String>);
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/generic_redirecting_factory_tear_off.dart:27:8: Error: Expected 1 type arguments.
+    f1a<int, String>(); // error
+       ^" in f1a{<inapplicable>}.<core::int, core::String>();
+  };
+  () → self::Class1<core::int> f1b = f1a<core::int>;
+  self::Class1<core::int> c1c = f1b(){() → self::Class1<core::int>};
+  self::expect(true, c1c is{ForNonNullableByDefault} self::Class1<core::int>);
+  self::expect(false, c1c is{ForNonNullableByDefault} self::Class1<core::String>);
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/generic_redirecting_factory_tear_off.dart:35:8: Error: Expected 0 type arguments.
+    f1b<int>(); // error
+       ^" in f1b{<inapplicable>}.<core::int>();
+  };
+  dynamic f1c = #C6;
+  dynamic c1d = f1c{dynamic}.call();
+  self::expect(true, c1a is{ForNonNullableByDefault} self::Class1<dynamic>);
+  self::expect(false, c1a is{ForNonNullableByDefault} self::Class1<core::int>);
+  self::throws(() → dynamic => f1c{dynamic}.call<core::int, core::String>());
+}
+static method testBounded() → dynamic {
+  <T extends core::num>() → self::Class2<T> f2a = #C7;
+  self::Class2<core::num> c2a = f2a<core::num>(){() → self::Class2<core::num>};
+  self::expect(true, c2a is{ForNonNullableByDefault} self::Class2<core::num>);
+  self::expect(false, c2a is{ForNonNullableByDefault} self::Class2<core::int>);
+  self::Class2<core::int> c2b = f2a<core::int>(){() → self::Class2<core::int>};
+  self::expect(true, c2b is{ForNonNullableByDefault} self::Class2<core::int>);
+  self::expect(false, c2b is{ForNonNullableByDefault} self::Class2<core::double>);
+  () → Null {
+    f2a<core::String>(){() → self::Class2<core::String>};
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/generic_redirecting_factory_tear_off.dart:75:8: Error: Expected 1 type arguments.
+    f2a<int, String>(); // error
+       ^" in f2a{<inapplicable>}.<core::int, core::String>();
+  };
+  dynamic f2b = #C7;
+  dynamic c2c = f2b{dynamic}.call();
+  self::expect(true, c2c is{ForNonNullableByDefault} self::Class2<core::num>);
+  self::expect(false, c2c is{ForNonNullableByDefault} self::Class2<core::int>);
+  dynamic c2d = f2b{dynamic}.call<core::int>();
+  self::expect(true, c2d is{ForNonNullableByDefault} self::Class2<core::int>);
+  self::expect(false, c2d is{ForNonNullableByDefault} self::Class2<core::double>);
+  self::throws(() → dynamic => f2b{dynamic}.call<core::String>());
+  self::throws(() → dynamic => f2b{dynamic}.call<core::int, core::String>());
+  <T extends S% = dynamic, S extends core::Object? = dynamic>() → self::Class3<T%, S%> f3a = #C8;
+  self::Class3<dynamic, dynamic> c3a = f3a<dynamic, dynamic>(){() → self::Class3<dynamic, dynamic>};
+  self::expect(true, c3a is{ForNonNullableByDefault} self::Class3<dynamic, dynamic>);
+  self::expect(false, c3a is{ForNonNullableByDefault} self::Class3<core::int, core::num>);
+  self::Class3<core::int, core::num> c3b = f3a<core::int, core::num>(){() → self::Class3<core::int, core::num>};
+  self::expect(true, c3b is{ForNonNullableByDefault} self::Class3<core::int, core::num>);
+  self::expect(false, c3b is{ForNonNullableByDefault} self::Class3<core::double, core::num>);
+  () → Null {
+    f3a<core::num, core::int>(){() → self::Class3<core::num, core::int>};
+  };
+  dynamic f3b = #C8;
+  dynamic c3c = f3b{dynamic}.call();
+  self::expect(true, c3c is{ForNonNullableByDefault} self::Class3<dynamic, dynamic>);
+  self::expect(false, c3c is{ForNonNullableByDefault} self::Class3<core::int, core::num>);
+  dynamic c3d = f3b{dynamic}.call<core::int, core::num>();
+  self::expect(true, c3d is{ForNonNullableByDefault} self::Class3<core::int, core::num>);
+  self::expect(false, c3d is{ForNonNullableByDefault} self::Class3<core::double, core::num>);
+  self::throws(() → dynamic => f3b{dynamic}.call<core::num, core::int>());
+  <T extends self::Class4<T> = self::Class4<dynamic>>() → self::Class4<T> f4a = #C9;
+  () → Null {
+    self::Class4<self::Class4<core::Object?>> c4a = f4a<self::Class4<core::Object?>>(){() → self::Class4<self::Class4<core::Object?>>};
+  };
+  dynamic f4b = #C9;
+  self::throws(() → dynamic => f4b{dynamic}.call());
+  dynamic c4b = f4b{dynamic}.call<self::Class4int>();
+  self::expect(true, c4b is{ForNonNullableByDefault} self::Class4<self::Class4int>);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, {core::bool inSoundModeOnly = #C10}) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print("Thrown: ${e}");
+    return;
+  }
+  if(!self::inSoundMode && inSoundModeOnly) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+constants  {
+  #C1 = constructor-tearoff self::Class1::•
+  #C2 = constructor-tearoff self::Class2::•
+  #C3 = constructor-tearoff self::Class3::•
+  #C4 = constructor-tearoff self::Class4::•
+  #C5 = constructor-tearoff self::Class4int::•
+  #C6 = static-tearoff self::Class1::_#new#tearOff
+  #C7 = static-tearoff self::Class2::_#new#tearOff
+  #C8 = static-tearoff self::Class3::_#new#tearOff
+  #C9 = static-tearoff self::Class4::_#new#tearOff
+  #C10 = false
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/inferred_constructor_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/inferred_constructor_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..da67936
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/inferred_constructor_tear_off.dart.weak.modular.expect
@@ -0,0 +1,97 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/inferred_constructor_tear_off.dart:38:9: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//     f1a(''); // error
+//         ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/inferred_constructor_tear_off.dart:52:9: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//     f2a(''); // error
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  field core::int field;
+  constructor •(core::int field) → self::Class1
+    : self::Class1::field = field, super core::Object::•()
+    ;
+  static method _#new#tearOff(core::int field) → self::Class1
+    return new self::Class1::•(field);
+}
+abstract class Interface2 extends core::Object {
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+  abstract get field() → core::int;
+}
+class Class2 extends core::Object implements self::Interface2 {
+  final field core::int field;
+  constructor •(core::int field) → self::Class2
+    : self::Class2::field = field, super core::Object::•()
+    ;
+  static method _#new#tearOff(core::int field) → self::Class2
+    return new self::Class2::•(field);
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static field (core::int) → self::Class1 Class1_new = #C1;
+static field (core::int) → self::Class2 Class2_new = #C2;
+static method main() → dynamic {
+  core::print("inSoundMode: ${self::inSoundMode}");
+  self::testInferred();
+}
+static method testInferred() → dynamic {
+  (core::int) → self::Class1 f1a = #C1;
+  self::expect(true, f1a is{ForNonNullableByDefault} (core::int) → self::Class1);
+  self::expect(false, f1a is{ForNonNullableByDefault} (core::String) → self::Class1);
+  self::Class1 c1a = f1a(0){(core::int) → self::Class1};
+  self::expect(true, c1a is{ForNonNullableByDefault} self::Class1);
+  () → Null {
+    f1a(invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/inferred_constructor_tear_off.dart:38:9: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+    f1a(''); // error
+        ^" in "" as{TypeError,ForNonNullableByDefault} core::int){(core::int) → self::Class1};
+  };
+  dynamic f1b = #C1;
+  dynamic c1b = f1b{dynamic}.call(0);
+  self::expect(true, c1b is{ForNonNullableByDefault} self::Class1);
+  self::throws(() → dynamic => f1b{dynamic}.call(""));
+  (core::int) → self::Class2 f2a = #C2;
+  self::expect(true, f2a is{ForNonNullableByDefault} (core::int) → self::Class2);
+  self::expect(false, f2a is{ForNonNullableByDefault} (core::String) → self::Class2);
+  self::Class2 c2a = f2a(0){(core::int) → self::Class2};
+  self::expect(true, c2a is{ForNonNullableByDefault} self::Class2);
+  () → Null {
+    f2a(invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/inferred_constructor_tear_off.dart:52:9: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+    f2a(''); // error
+        ^" in "" as{TypeError,ForNonNullableByDefault} core::int){(core::int) → self::Class2};
+  };
+  dynamic f2b = #C2;
+  dynamic c2b = f2b{dynamic}.call(0);
+  self::expect(true, c2b is{ForNonNullableByDefault} self::Class2);
+  self::throws(() → dynamic => f2b{dynamic}.call(""));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, {core::bool inSoundModeOnly = #C3}) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print("Thrown: ${e}");
+    return;
+  }
+  if(!self::inSoundMode && inSoundModeOnly) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+constants  {
+  #C1 = static-tearoff self::Class1::_#new#tearOff
+  #C2 = static-tearoff self::Class2::_#new#tearOff
+  #C3 = false
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/inferred_non_proper_rename.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/inferred_non_proper_rename.dart.weak.modular.expect
new file mode 100644
index 0000000..6075c15
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/inferred_non_proper_rename.dart.weak.modular.expect
@@ -0,0 +1,106 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef F<X extends core::num> = self::A<X>;
+typedef G<unrelated Y extends core::Object? = dynamic> = self::A<core::int>;
+typedef H<X extends core::Object? = dynamic, unrelated Y extends core::Object? = dynamic> = self::A<X%>;
+class A<T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::A<self::A::_#new#tearOff::T%>
+    return new self::A::•<self::A::_#new#tearOff::T%>();
+  static factory fact<T extends core::Object? = dynamic>() → self::A<self::A::fact::T%>
+    return new self::A::•<self::A::fact::T%>();
+  static method _#fact#tearOff<T extends core::Object? = dynamic>() → self::A<self::A::_#fact#tearOff::T%>
+    return self::A::fact<self::A::_#fact#tearOff::T%>();
+  static factory redirect<T extends core::Object? = dynamic>() → self::A<self::A::redirect::T%>
+    return new self::A::•<self::A::redirect::T%>();
+  static method _#redirect#tearOff<T extends core::Object? = dynamic>() → self::A<self::A::_#redirect#tearOff::T%>
+    return new self::A::•<self::A::_#redirect#tearOff::T%>();
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static const field () → self::A<core::int> f1a = #C3;
+static const field () → self::A<core::int> f1b = #C3;
+static const field () → self::A<core::int> f1c = #C3;
+static const field () → self::A<core::int> f1d = #C5;
+static const field () → self::A<core::int> f1e = #C5;
+static const field () → self::A<core::int> f1f = #C5;
+static const field () → self::A<core::int> f1g = #C7;
+static const field () → self::A<core::int> f1h = #C7;
+static const field () → self::A<core::int> f1i = #C7;
+static const field () → self::A<core::int> g1a = #C3;
+static const field () → self::A<core::int> g1b = #C3;
+static const field () → self::A<core::int> g1c = #C3;
+static const field () → self::A<core::int> h1a = #C3;
+static const field () → self::A<core::int> h1b = #C3;
+static const field () → self::A<core::int> h1c = #C3;
+static method main() → dynamic {
+  self::test<core::int>();
+  core::identical(#C3, #C3);
+  core::identical(#C3, #C3);
+  core::identical(#C5, #C5);
+  core::identical(#C5, #C5);
+  core::identical(#C7, #C7);
+  core::identical(#C7, #C7);
+  core::identical(#C3, #C3);
+  core::identical(#C3, #C3);
+  core::identical(#C3, #C3);
+  core::identical(#C3, #C3);
+}
+static method test<T extends core::num>() → dynamic {
+  () → self::A<self::test::T> f2a = #C2<self::test::T>;
+  () → self::A<self::test::T> f2b = #C2<self::test::T>;
+  () → self::A<self::test::T> f2c = #C2<self::test::T>;
+  () → self::A<self::test::T> f2d = #C4<self::test::T>;
+  () → self::A<self::test::T> f2e = #C4<self::test::T>;
+  () → self::A<self::test::T> f2f = #C4<self::test::T>;
+  () → self::A<self::test::T> f2g = #C6<self::test::T>;
+  () → self::A<self::test::T> f2h = #C6<self::test::T>;
+  () → self::A<self::test::T> f2i = #C6<self::test::T>;
+  () → self::A<core::int> g2a = #C3;
+  () → self::A<core::int> g2b = #C3;
+  () → self::A<core::int> g2c = #C3;
+  () → self::A<self::test::T> h2a = #C2<self::test::T>;
+  () → self::A<self::test::T> h2b = #C2<self::test::T>;
+  () → self::A<self::test::T> h2c = #C2<self::test::T>;
+  self::expect(#C3, g2a);
+  self::expect(g2a, g2b);
+  if(self::inSoundMode) {
+    self::expect(g2a, g2c);
+  }
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method _#F#new#tearOff<X extends core::num>() → self::A<self::_#F#new#tearOff::X>
+  return new self::A::•<self::_#F#new#tearOff::X>();
+static method _#F#fact#tearOff<X extends core::num>() → self::A<self::_#F#fact#tearOff::X>
+  return self::A::fact<self::_#F#fact#tearOff::X>();
+static method _#F#redirect#tearOff<X extends core::num>() → self::A<self::_#F#redirect#tearOff::X>
+  return self::A::_#redirect#tearOff<self::_#F#redirect#tearOff::X>();
+static method _#G#new#tearOff<unrelated Y extends core::Object? = dynamic>() → self::A<core::int>
+  return new self::A::•<core::int>();
+static method _#G#fact#tearOff<unrelated Y extends core::Object? = dynamic>() → self::A<core::int>
+  return self::A::fact<core::int>();
+static method _#G#redirect#tearOff<unrelated Y extends core::Object? = dynamic>() → self::A<core::int>
+  return self::A::_#redirect#tearOff<core::int>();
+static method _#H#new#tearOff<X extends core::Object? = dynamic, unrelated Y extends core::Object? = dynamic>() → self::A<self::_#H#new#tearOff::X%>
+  return new self::A::•<self::_#H#new#tearOff::X%>();
+static method _#H#fact#tearOff<X extends core::Object? = dynamic, unrelated Y extends core::Object? = dynamic>() → self::A<self::_#H#fact#tearOff::X%>
+  return self::A::fact<self::_#H#fact#tearOff::X%>();
+static method _#H#redirect#tearOff<X extends core::Object? = dynamic, unrelated Y extends core::Object? = dynamic>() → self::A<self::_#H#redirect#tearOff::X%>
+  return self::A::_#redirect#tearOff<self::_#H#redirect#tearOff::X%>();
+
+constants  {
+  #C1 = constructor-tearoff self::A::redirect
+  #C2 = static-tearoff self::A::_#new#tearOff
+  #C3 = instantiation #C2 <core::int*>
+  #C4 = static-tearoff self::A::_#fact#tearOff
+  #C5 = instantiation #C4 <core::int*>
+  #C6 = static-tearoff self::A::_#redirect#tearOff
+  #C7 = instantiation #C6 <core::int*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/inferred_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/inferred_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..3414686
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/inferred_tear_off.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef F<unrelated T extends core::Object? = dynamic> = self::A;
+typedef G<unrelated T extends core::num> = self::B<dynamic>;
+class A extends core::Object {
+  field core::int field1 = 0;
+  constructor •(core::int field1) → self::A
+    : self::A::field1 = field1, super core::Object::•()
+    ;
+  constructor named(core::int field1) → self::A
+    : self::A::field1 = field1, super core::Object::•()
+    ;
+  static method _#new#tearOff(core::int field1) → self::A
+    return new self::A::•(field1);
+  static method _#named#tearOff(core::int field1) → self::A
+    return new self::A::named(field1);
+}
+class B<T extends core::Object? = dynamic> extends core::Object implements self::A {
+  field core::int field1;
+  covariant-by-class field self::B::T% field2;
+  constructor •(core::int field1, self::B::T% field2) → self::B<self::B::T%>
+    : self::B::field1 = field1, self::B::field2 = field2, super core::Object::•()
+    ;
+  constructor named(core::int field1, self::B::T% field2) → self::B<self::B::T%>
+    : self::B::field1 = field1, self::B::field2 = field2, super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>(core::int field1, self::B::_#new#tearOff::T% field2) → self::B<self::B::_#new#tearOff::T%>
+    return new self::B::•<self::B::_#new#tearOff::T%>(field1, field2);
+  static method _#named#tearOff<T extends core::Object? = dynamic>(core::int field1, self::B::_#named#tearOff::T% field2) → self::B<self::B::_#named#tearOff::T%>
+    return new self::B::named<self::B::_#named#tearOff::T%>(field1, field2);
+}
+static field (core::int) → self::A A_new = #C1;
+static field <T extends core::Object? = dynamic>(core::int, T%) → self::B<T%> B_new = #C2;
+static field <unrelated T extends core::Object? = dynamic>(core::int) → self::A F_new = #C3;
+static field <unrelated T extends core::num>(core::int, dynamic) → self::B<dynamic> G_new = #C4;
+static field (core::int) → self::A A_named = #C5;
+static field (core::int, core::int) → self::B<core::int> B_named = #C7;
+static field <unrelated T extends core::Object? = dynamic>(core::int) → self::A F_named = #C8;
+static field (core::int, dynamic) → self::B<dynamic> G_named = #C9;
+static method main() → dynamic {}
+static method _#F#new#tearOff<unrelated T extends core::Object? = dynamic>(core::int field1) → self::A
+  return new self::A::•(field1);
+static method _#F#named#tearOff<unrelated T extends core::Object? = dynamic>(core::int field1) → self::A
+  return new self::A::named(field1);
+static method _#G#new#tearOff<unrelated T extends core::num>(core::int field1, dynamic field2) → self::B<dynamic>
+  return new self::B::•<dynamic>(field1, field2);
+static method _#G#named#tearOff<unrelated T extends core::num>(core::int field1, dynamic field2) → self::B<dynamic>
+  return new self::B::named<dynamic>(field1, field2);
+
+constants  {
+  #C1 = static-tearoff self::A::_#new#tearOff
+  #C2 = static-tearoff self::B::_#new#tearOff
+  #C3 = static-tearoff self::_#F#new#tearOff
+  #C4 = static-tearoff self::_#G#new#tearOff
+  #C5 = static-tearoff self::A::_#named#tearOff
+  #C6 = static-tearoff self::B::_#named#tearOff
+  #C7 = instantiation #C6 <core::int*>
+  #C8 = static-tearoff self::_#F#named#tearOff
+  #C9 = instantiation #C6 <dynamic>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/issue47462.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/issue47462.dart.weak.modular.expect
new file mode 100644
index 0000000..2a6bd0b
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/issue47462.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef MyList<T extends core::num> = core::List<T>;
+static method main() → dynamic {
+  self::expect(true, #C1);
+  self::expect(false, #C2);
+  self::expect(true, core::identical(#C4, #C4));
+  self::expect(false, core::identical(#C4, #C6));
+  (core::int, core::num, {growable: core::bool}) → core::List<core::num> v1 = #C4;
+  (core::int, core::num, {growable: core::bool}) → core::List<core::num> v2 = #C4;
+  (core::int, core::num, {growable: core::bool}) → core::List<core::num> v3 = #C6;
+  core::bool v4 = core::identical(v1, v2);
+  core::bool v5 = core::identical(v1, v3);
+  self::expect(true, v4);
+  self::expect(false, v5);
+  self::expect(true, core::identical(v1, v2));
+  self::expect(false, core::identical(v1, v3));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/array_patch.dart */ _#MyList#new#tearOff<T extends core::num>([core::int? length = #C7]) → core::List<self::_#MyList#new#tearOff::T>
+  return core::List::•<self::_#MyList#new#tearOff::T>(length);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/array_patch.dart */ _#MyList#filled#tearOff<T extends core::num>(core::int length, self::_#MyList#filled#tearOff::T fill, {core::bool growable = #C2}) → core::List<self::_#MyList#filled#tearOff::T>
+  return core::List::filled<self::_#MyList#filled#tearOff::T>(length, fill, growable: growable);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/array_patch.dart */ _#MyList#empty#tearOff<T extends core::num>({core::bool growable = #C2}) → core::List<self::_#MyList#empty#tearOff::T>
+  return core::List::empty<self::_#MyList#empty#tearOff::T>(growable: growable);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/array_patch.dart */ _#MyList#from#tearOff<T extends core::num>(core::Iterable<dynamic> elements, {core::bool growable = #C1}) → core::List<self::_#MyList#from#tearOff::T>
+  return core::List::from<self::_#MyList#from#tearOff::T>(elements, growable: growable);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/array_patch.dart */ _#MyList#of#tearOff<T extends core::num>(core::Iterable<self::_#MyList#of#tearOff::T> elements, {core::bool growable = #C1}) → core::List<self::_#MyList#of#tearOff::T>
+  return core::List::of<self::_#MyList#of#tearOff::T>(elements, growable: growable);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/array_patch.dart */ _#MyList#generate#tearOff<T extends core::num>(core::int length, (core::int) → self::_#MyList#generate#tearOff::T generator, {core::bool growable = #C1}) → core::List<self::_#MyList#generate#tearOff::T>
+  return core::List::generate<self::_#MyList#generate#tearOff::T>(length, generator, growable: growable);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/array_patch.dart */ _#MyList#unmodifiable#tearOff<T extends core::num>(core::Iterable<dynamic> elements) → core::List<self::_#MyList#unmodifiable#tearOff::T>
+  return core::List::unmodifiable<self::_#MyList#unmodifiable#tearOff::T>(elements);
+
+constants  {
+  #C1 = true
+  #C2 = false
+  #C3 = constructor-tearoff core::List::filled
+  #C4 = instantiation #C3 <core::num*>
+  #C5 = static-tearoff self::_#MyList#filled#tearOff
+  #C6 = instantiation #C5 <core::num*>
+  #C7 = null
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart.weak.modular.expect
new file mode 100644
index 0000000..309b5f6
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart.weak.modular.expect
@@ -0,0 +1,116 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:15:8: Error: A constructor tear-off can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   A.new<int>;
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:16:10: Error: A constructor tear-off can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   A.named<int>;
+//          ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:17:9: Error: A constructor tear-off can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   A.fact<int>;
+//         ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:18:13: Error: A constructor tear-off can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   A.redirect<int>;
+//             ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:19:8: Error: A constructor tear-off can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   B.new<int>;
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:20:10: Error: A constructor tear-off can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   B.named<int>;
+//          ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:21:9: Error: A constructor tear-off can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   B.fact<int>;
+//         ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:22:13: Error: A constructor tear-off can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   B.redirect<int>;
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef B<T extends core::num> = self::A<T>;
+class A<T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+  constructor named() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::A<self::A::_#new#tearOff::T%>
+    return new self::A::•<self::A::_#new#tearOff::T%>();
+  static method _#named#tearOff<T extends core::Object? = dynamic>() → self::A<self::A::_#named#tearOff::T%>
+    return new self::A::named<self::A::_#named#tearOff::T%>();
+  static factory fact<T extends core::Object? = dynamic>() → self::A<self::A::fact::T%>
+    return new self::A::•<self::A::fact::T%>();
+  static method _#fact#tearOff<T extends core::Object? = dynamic>() → self::A<self::A::_#fact#tearOff::T%>
+    return self::A::fact<self::A::_#fact#tearOff::T%>();
+  static factory redirect<T extends core::Object? = dynamic>() → self::A<self::A::redirect::T%>
+    return new self::A::•<self::A::redirect::T%>();
+  static method _#redirect#tearOff<T extends core::Object? = dynamic>() → self::A<self::A::_#redirect#tearOff::T%>
+    return new self::A::•<self::A::_#redirect#tearOff::T%>();
+}
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:15:8: Error: A constructor tear-off can't have type arguments after the constructor name.
+Try removing the type arguments or placing them after the class name.
+  A.new<int>;
+       ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:16:10: Error: A constructor tear-off can't have type arguments after the constructor name.
+Try removing the type arguments or placing them after the class name.
+  A.named<int>;
+         ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:17:9: Error: A constructor tear-off can't have type arguments after the constructor name.
+Try removing the type arguments or placing them after the class name.
+  A.fact<int>;
+        ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:18:13: Error: A constructor tear-off can't have type arguments after the constructor name.
+Try removing the type arguments or placing them after the class name.
+  A.redirect<int>;
+            ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:19:8: Error: A constructor tear-off can't have type arguments after the constructor name.
+Try removing the type arguments or placing them after the class name.
+  B.new<int>;
+       ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:20:10: Error: A constructor tear-off can't have type arguments after the constructor name.
+Try removing the type arguments or placing them after the class name.
+  B.named<int>;
+         ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:21:9: Error: A constructor tear-off can't have type arguments after the constructor name.
+Try removing the type arguments or placing them after the class name.
+  B.fact<int>;
+        ^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/misplaced_type_arguments.dart:22:13: Error: A constructor tear-off can't have type arguments after the constructor name.
+Try removing the type arguments or placing them after the class name.
+  B.redirect<int>;
+            ^";
+}
+static method main() → dynamic {}
+static method _#B#new#tearOff<T extends core::num>() → self::A<self::_#B#new#tearOff::T>
+  return new self::A::•<self::_#B#new#tearOff::T>();
+static method _#B#named#tearOff<T extends core::num>() → self::A<self::_#B#named#tearOff::T>
+  return new self::A::named<self::_#B#named#tearOff::T>();
+static method _#B#fact#tearOff<T extends core::num>() → self::A<self::_#B#fact#tearOff::T>
+  return self::A::fact<self::_#B#fact#tearOff::T>();
+static method _#B#redirect#tearOff<T extends core::num>() → self::A<self::_#B#redirect#tearOff::T>
+  return self::A::_#redirect#tearOff<self::_#B#redirect#tearOff::T>();
+
+constants  {
+  #C1 = constructor-tearoff self::A::redirect
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/missing_redirecting_target.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/missing_redirecting_target.dart.weak.modular.expect
new file mode 100644
index 0000000..f19d273
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/missing_redirecting_target.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/missing_redirecting_target.dart:10:23: Error: Redirection constructor target not found: 'Class.nonexisting'
+//   factory Class.a() = Class.nonexisting;
+//                       ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/missing_redirecting_target.dart:11:23: Error: Redirection constructor target not found: 'Class.constructor'
+//   factory Class.b() = Class.constructor;
+//                       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  static field () → self::Class field = () → self::Class => new self::Class::_();
+  static final field dynamic _redirecting# = <dynamic>[#C1, #C2]/*isLegacy*/;
+  constructor _() → self::Class
+    : super core::Object::•()
+    ;
+  static method _#_#tearOff() → self::Class
+    return new self::Class::_();
+  static method constructor() → self::Class
+    return new self::Class::_();
+  static factory a() → self::Class
+    return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/missing_redirecting_target.dart:10:23: Error: Redirection constructor target not found: 'Class.nonexisting'
+  factory Class.a() = Class.nonexisting;
+                      ^";
+  static method _#a#tearOff() → self::Class;
+  static factory b() → self::Class
+    return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/missing_redirecting_target.dart:11:23: Error: Redirection constructor target not found: 'Class.constructor'
+  factory Class.b() = Class.constructor;
+                      ^";
+  static method _#b#tearOff() → self::Class;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::Class::a
+  #C2 = constructor-tearoff self::Class::b
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart.weak.modular.expect
new file mode 100644
index 0000000..841838c
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart.weak.modular.expect
@@ -0,0 +1,146 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart:26:25: Error: Member not found: 'fact'.
+//   NamedMixinApplication.fact;
+//                         ^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart:27:25: Error: Member not found: 'redirectingFactory'.
+//   NamedMixinApplication.redirectingFactory;
+//                         ^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart:29:33: Error: Constructors on abstract classes can't be torn off.
+//   AbstractNamedMixinApplication.new;
+//                                 ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart:30:33: Error: Constructors on abstract classes can't be torn off.
+//   AbstractNamedMixinApplication.named;
+//                                 ^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart:31:33: Error: Constructors on abstract classes can't be torn off.
+//   AbstractNamedMixinApplication.redirectingGenerative;
+//                                 ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart:32:33: Error: Member not found: 'fact'.
+//   AbstractNamedMixinApplication.fact;
+//                                 ^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart:33:33: Error: Member not found: 'redirectingFactory'.
+//   AbstractNamedMixinApplication.redirectingFactory;
+//                                 ^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  abstract get field() → core::int;
+}
+class Class<T extends core::Object? = dynamic> extends core::Object implements self::Interface {
+  field core::int field;
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor •([core::int field = #C2]) → self::Class<self::Class::T%>
+    : self::Class::field = field, super core::Object::•()
+    ;
+  constructor named(core::int field) → self::Class<self::Class::T%>
+    : self::Class::field = field, super core::Object::•()
+    ;
+  constructor redirectingGenerative(core::int field) → self::Class<self::Class::T%>
+    : this self::Class::•(field)
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>([core::int field = #C2]) → self::Class<self::Class::_#new#tearOff::T%>
+    return new self::Class::•<self::Class::_#new#tearOff::T%>(field);
+  static method _#named#tearOff<T extends core::Object? = dynamic>(core::int field) → self::Class<self::Class::_#named#tearOff::T%>
+    return new self::Class::named<self::Class::_#named#tearOff::T%>(field);
+  static method _#redirectingGenerative#tearOff<T extends core::Object? = dynamic>(core::int field) → self::Class<self::Class::_#redirectingGenerative#tearOff::T%>
+    return new self::Class::redirectingGenerative<self::Class::_#redirectingGenerative#tearOff::T%>(field);
+  static factory fact<T extends core::Object? = dynamic>(core::int field) → self::Class<self::Class::fact::T%>
+    return new self::Class::•<self::Class::fact::T%>(field);
+  static method _#fact#tearOff<T extends core::Object? = dynamic>(core::int field) → self::Class<self::Class::_#fact#tearOff::T%>
+    return self::Class::fact<self::Class::_#fact#tearOff::T%>(field);
+  static factory redirectingFactory<T extends core::Object? = dynamic>(core::int field) → self::Class<self::Class::redirectingFactory::T%>
+    return new self::Class::•<self::Class::redirectingFactory::T%>(field);
+  static method _#redirectingFactory#tearOff<T extends core::Object? = dynamic>(core::int field = #C2) → self::Class<self::Class::_#redirectingFactory#tearOff::T%>
+    return new self::Class::•<self::Class::_#redirectingFactory#tearOff::T%>(field);
+}
+abstract class Mixin<S extends core::Object? = dynamic> extends core::Object /*isMixinDeclaration*/  {
+}
+class NamedMixinApplication<T extends core::Object? = dynamic, S extends core::Object? = dynamic> = self::Class<self::NamedMixinApplication::T%> with self::Mixin<self::NamedMixinApplication::S%> {
+  synthetic constructor •([core::int field = #C2]) → self::NamedMixinApplication<self::NamedMixinApplication::T%, self::NamedMixinApplication::S%>
+    : super self::Class::•(field)
+    ;
+  synthetic constructor named(core::int field) → self::NamedMixinApplication<self::NamedMixinApplication::T%, self::NamedMixinApplication::S%>
+    : super self::Class::named(field)
+    ;
+  synthetic constructor redirectingGenerative(core::int field) → self::NamedMixinApplication<self::NamedMixinApplication::T%, self::NamedMixinApplication::S%>
+    : super self::Class::redirectingGenerative(field)
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic, S extends core::Object? = dynamic>([core::int field]) → self::NamedMixinApplication<self::NamedMixinApplication::_#new#tearOff::T%, self::NamedMixinApplication::_#new#tearOff::S%>
+    return new self::NamedMixinApplication::•<self::NamedMixinApplication::_#new#tearOff::T%, self::NamedMixinApplication::_#new#tearOff::S%>(field);
+  static method _#named#tearOff<T extends core::Object? = dynamic, S extends core::Object? = dynamic>(core::int field) → self::NamedMixinApplication<self::NamedMixinApplication::_#named#tearOff::T%, self::NamedMixinApplication::_#named#tearOff::S%>
+    return new self::NamedMixinApplication::named<self::NamedMixinApplication::_#named#tearOff::T%, self::NamedMixinApplication::_#named#tearOff::S%>(field);
+  static method _#redirectingGenerative#tearOff<T extends core::Object? = dynamic, S extends core::Object? = dynamic>(core::int field) → self::NamedMixinApplication<self::NamedMixinApplication::_#redirectingGenerative#tearOff::T%, self::NamedMixinApplication::_#redirectingGenerative#tearOff::S%>
+    return new self::NamedMixinApplication::redirectingGenerative<self::NamedMixinApplication::_#redirectingGenerative#tearOff::T%, self::NamedMixinApplication::_#redirectingGenerative#tearOff::S%>(field);
+}
+abstract class AbstractNamedMixinApplication<T extends core::Object? = dynamic, S extends core::Object? = dynamic> = self::Class<self::AbstractNamedMixinApplication::T%> with self::Mixin<self::AbstractNamedMixinApplication::S%> {
+  synthetic constructor •([core::int field = #C2]) → self::AbstractNamedMixinApplication<self::AbstractNamedMixinApplication::T%, self::AbstractNamedMixinApplication::S%>
+    : super self::Class::•(field)
+    ;
+  synthetic constructor named(core::int field) → self::AbstractNamedMixinApplication<self::AbstractNamedMixinApplication::T%, self::AbstractNamedMixinApplication::S%>
+    : super self::Class::named(field)
+    ;
+  synthetic constructor redirectingGenerative(core::int field) → self::AbstractNamedMixinApplication<self::AbstractNamedMixinApplication::T%, self::AbstractNamedMixinApplication::S%>
+    : super self::Class::redirectingGenerative(field)
+    ;
+}
+static field <T extends core::Object? = dynamic, S extends core::Object? = dynamic>([core::int]) → self::NamedMixinApplication<T%, S%> f1 = #C3;
+static field <T extends core::Object? = dynamic, S extends core::Object? = dynamic>(core::int) → self::NamedMixinApplication<T%, S%> f2 = #C4;
+static field <T extends core::Object? = dynamic, S extends core::Object? = dynamic>(core::int) → self::NamedMixinApplication<T%, S%> f3 = #C5;
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart:26:25: Error: Member not found: 'fact'.
+  NamedMixinApplication.fact;
+                        ^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart:27:25: Error: Member not found: 'redirectingFactory'.
+  NamedMixinApplication.redirectingFactory;
+                        ^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart:29:33: Error: Constructors on abstract classes can't be torn off.
+  AbstractNamedMixinApplication.new;
+                                ^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart:30:33: Error: Constructors on abstract classes can't be torn off.
+  AbstractNamedMixinApplication.named;
+                                ^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart:31:33: Error: Constructors on abstract classes can't be torn off.
+  AbstractNamedMixinApplication.redirectingGenerative;
+                                ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart:32:33: Error: Member not found: 'fact'.
+  AbstractNamedMixinApplication.fact;
+                                ^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart:33:33: Error: Member not found: 'redirectingFactory'.
+  AbstractNamedMixinApplication.redirectingFactory;
+                                ^^^^^^^^^^^^^^^^^^";
+}
+static method main() → dynamic {
+  <T extends core::Object? = dynamic, S extends core::Object? = dynamic>([core::int]) → self::NamedMixinApplication<T%, S%> f1 = #C3;
+  <T extends core::Object? = dynamic, S extends core::Object? = dynamic>(core::int) → self::NamedMixinApplication<T%, S%> f2 = #C4;
+  <T extends core::Object? = dynamic, S extends core::Object? = dynamic>(core::int) → self::NamedMixinApplication<T%, S%> f3 = #C5;
+  #C6;
+  #C7;
+  #C8;
+  ([core::int]) → self::NamedMixinApplication<core::int, core::String> n1 = f1<core::int, core::String>;
+  (core::int) → self::NamedMixinApplication<core::int, core::String> n2 = f2<core::int, core::String>;
+  (core::int) → self::NamedMixinApplication<core::int, core::String> n3 = f3<core::int, core::String>;
+}
+
+constants  {
+  #C1 = constructor-tearoff self::Class::redirectingFactory
+  #C2 = 0
+  #C3 = static-tearoff self::NamedMixinApplication::_#new#tearOff
+  #C4 = static-tearoff self::NamedMixinApplication::_#named#tearOff
+  #C5 = static-tearoff self::NamedMixinApplication::_#redirectingGenerative#tearOff
+  #C6 = instantiation #C3 <core::int*, core::String*>
+  #C7 = instantiation #C4 <core::int*, core::String*>
+  #C8 = instantiation #C5 <core::int*, core::String*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart.weak.outline.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart.weak.outline.expect
index 6aab2c5..37b4b1f 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/named_mixin_application.dart.weak.outline.expect
@@ -10,7 +10,7 @@
 class Class<T extends core::Object? = dynamic> extends core::Object implements self::Interface {
   field core::int field;
   static final field dynamic _redirecting# = <dynamic>[self::Class::redirectingFactory]/*isLegacy*/;
-  constructor •([core::int field]) → self::Class<self::Class::T%>
+  constructor •([core::int field = 0]) → self::Class<self::Class::T%>
     ;
   constructor named(core::int field) → self::Class<self::Class::T%>
     ;
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/non_class_typedefs.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/non_class_typedefs.dart.weak.modular.expect
new file mode 100644
index 0000000..715328b
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/non_class_typedefs.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+typedef S1<unrelated T extends core::Object? = dynamic> = dynamic;
+typedef S2<unrelated T extends core::Object? = dynamic> = Null;
+typedef S3<unrelated T extends core::Object? = dynamic> = void;
+typedef S4<unrelated T extends core::Object? = dynamic> = FutureOr<dynamic>;
+typedef S5<T extends core::Object? = dynamic> = FutureOr<T%>;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/proper_rename.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/proper_rename.dart.weak.modular.expect
new file mode 100644
index 0000000..b2e567f
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/proper_rename.dart.weak.modular.expect
@@ -0,0 +1,108 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef F = self::A;
+typedef G0 = self::B<dynamic>;
+typedef G1 = self::B<core::int>;
+typedef G2<T extends core::Object? = dynamic> = self::B<T%>;
+typedef G3<T extends core::num> = self::B<T>;
+typedef H0 = self::C<dynamic, dynamic>;
+typedef H1 = self::C<core::int, core::String>;
+typedef H2<T extends core::Object? = dynamic> = self::C<core::int, T%>;
+typedef H3<T extends core::Object? = dynamic, S extends core::Object? = dynamic> = self::C<T%, S%>;
+typedef H4<T extends core::Object? = dynamic, S extends core::Object? = dynamic> = self::C<S%, T%>;
+typedef H5<T extends core::num, S extends core::Object? = dynamic> = self::C<T, S%>;
+typedef H6<T extends core::Object? = dynamic, S extends core::num> = self::C<T%, S>;
+typedef I0 = self::D<core::num>;
+typedef I1 = self::D<core::num>;
+typedef I2<T extends core::num> = self::D<T>;
+typedef I3<T extends core::int> = self::D<T>;
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff() → self::A
+    return new self::A::•();
+}
+class B<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::B<self::B::_#new#tearOff::T%>
+    return new self::B::•<self::B::_#new#tearOff::T%>();
+}
+class C<X extends core::Object? = dynamic, Y extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::X%, self::C::Y%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → self::C<self::C::_#new#tearOff::X%, self::C::_#new#tearOff::Y%>
+    return new self::C::•<self::C::_#new#tearOff::X%, self::C::_#new#tearOff::Y%>();
+}
+class D<X extends core::num> extends core::Object {
+  synthetic constructor •() → self::D<self::D::X>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<X extends core::num>() → self::D<self::D::_#new#tearOff::X>
+    return new self::D::•<self::D::_#new#tearOff::X>();
+}
+static method main() → dynamic {
+  () → self::A f = #C1;
+  () → self::B<dynamic> g0 = #C3;
+  () → self::B<core::int> g1 = #C4;
+  <T extends core::Object? = dynamic>() → self::B<T%> g2a = #C2;
+  () → self::B<core::int> g2b = #C4;
+  <T extends core::num>() → self::B<T> g3a = #C5;
+  () → self::B<core::int> g3b = #C4;
+  () → self::C<dynamic, dynamic> h0 = #C7;
+  () → self::C<core::int, core::String> h1 = #C8;
+  <T extends core::Object? = dynamic>() → self::C<core::int, T%> h2a = #C9;
+  () → self::C<core::int, core::int> h2b = #C10;
+  <X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → self::C<X%, Y%> h3a = #C6;
+  () → self::C<core::int, core::String> h3b = #C8;
+  <T extends core::Object? = dynamic, S extends core::Object? = dynamic>() → self::C<S%, T%> h4a = #C11;
+  () → self::C<core::String, core::int> h4b = #C12;
+  <T extends core::num, S extends core::Object? = dynamic>() → self::C<T, S%> h5a = #C13;
+  () → self::C<core::int, core::String> h5b = #C8;
+  <T extends core::Object? = dynamic, S extends core::num>() → self::C<T%, S> h6a = #C14;
+  () → self::C<core::String, core::int> h6b = #C12;
+  () → self::D<core::num> i0 = #C16;
+  () → self::D<core::num> i1 = #C16;
+  <X extends core::num>() → self::D<X> i2a = #C15;
+  () → self::D<core::int> i2b = #C17;
+  <T extends core::int>() → self::D<T> i3a = #C18;
+  () → self::D<core::int> i3b = #C17;
+}
+static method _#G3#new#tearOff<T extends core::num>() → self::B<self::_#G3#new#tearOff::T>
+  return new self::B::•<self::_#G3#new#tearOff::T>();
+static method _#H2#new#tearOff<T extends core::Object? = dynamic>() → self::C<core::int, self::_#H2#new#tearOff::T%>
+  return new self::C::•<core::int, self::_#H2#new#tearOff::T%>();
+static method _#H4#new#tearOff<T extends core::Object? = dynamic, S extends core::Object? = dynamic>() → self::C<self::_#H4#new#tearOff::S%, self::_#H4#new#tearOff::T%>
+  return new self::C::•<self::_#H4#new#tearOff::S%, self::_#H4#new#tearOff::T%>();
+static method _#H5#new#tearOff<T extends core::num, S extends core::Object? = dynamic>() → self::C<self::_#H5#new#tearOff::T, self::_#H5#new#tearOff::S%>
+  return new self::C::•<self::_#H5#new#tearOff::T, self::_#H5#new#tearOff::S%>();
+static method _#H6#new#tearOff<T extends core::Object? = dynamic, S extends core::num>() → self::C<self::_#H6#new#tearOff::T%, self::_#H6#new#tearOff::S>
+  return new self::C::•<self::_#H6#new#tearOff::T%, self::_#H6#new#tearOff::S>();
+static method _#I3#new#tearOff<T extends core::int>() → self::D<self::_#I3#new#tearOff::T>
+  return new self::D::•<self::_#I3#new#tearOff::T>();
+
+constants  {
+  #C1 = static-tearoff self::A::_#new#tearOff
+  #C2 = static-tearoff self::B::_#new#tearOff
+  #C3 = instantiation #C2 <dynamic>
+  #C4 = instantiation #C2 <core::int*>
+  #C5 = static-tearoff self::_#G3#new#tearOff
+  #C6 = static-tearoff self::C::_#new#tearOff
+  #C7 = instantiation #C6 <dynamic, dynamic>
+  #C8 = instantiation #C6 <core::int*, core::String*>
+  #C9 = static-tearoff self::_#H2#new#tearOff
+  #C10 = instantiation #C6 <core::int*, core::int*>
+  #C11 = static-tearoff self::_#H4#new#tearOff
+  #C12 = instantiation #C6 <core::String*, core::int*>
+  #C13 = static-tearoff self::_#H5#new#tearOff
+  #C14 = static-tearoff self::_#H6#new#tearOff
+  #C15 = static-tearoff self::D::_#new#tearOff
+  #C16 = instantiation #C15 <core::num*>
+  #C17 = instantiation #C15 <core::int*>
+  #C18 = static-tearoff self::_#I3#new#tearOff
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..214d583
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart.weak.modular.expect
@@ -0,0 +1,332 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:101:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f3a(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:102:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f3a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:117:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f4a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:131:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f5a(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:132:8: Error: Too many positional arguments: 2 allowed, but 3 found.
+// Try removing the extra positional arguments.
+//     f5a(42, 87, 123); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:144:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f6a(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:145:8: Error: Required named parameter 'field3' must be provided.
+//     f6a(42); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:146:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f6a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:147:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f6a(field1: 87, field2: 87); // error
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor _() → self::Class1
+    : super core::Object::•()
+    ;
+  static method _#_#tearOff() → self::Class1
+    return new self::Class1::_();
+  static factory •() → self::Class1
+    return new self::Class1::_();
+  static method _#new#tearOff() → self::Class1
+    return new self::Class1::_();
+}
+class Class2 extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C2]/*isLegacy*/;
+  constructor __() → self::Class2
+    : super core::Object::•()
+    ;
+  static method _#__#tearOff() → self::Class2
+    return new self::Class2::__();
+  static factory _() → self::Class2
+    return new self::Class2::__();
+  static method _#_#tearOff() → self::Class2
+    return self::Class2::_();
+  static factory named() → self::Class2
+    return self::Class2::_();
+  static method _#named#tearOff() → self::Class2
+    return self::Class2::_();
+}
+class Class3 extends core::Object {
+  final field core::int field;
+  static final field dynamic _redirecting# = <dynamic>[#C3]/*isLegacy*/;
+  constructor _(core::int field) → self::Class3
+    : self::Class3::field = field, super core::Object::•()
+    ;
+  static method _#_#tearOff(core::int field) → self::Class3
+    return new self::Class3::_(field);
+  static factory •(core::int field) → self::Class3
+    return new self::Class3::_(field);
+  static method _#new#tearOff(core::int field) → self::Class3
+    return new self::Class3::_(field);
+}
+class Class4 extends core::Object {
+  final field core::int? field;
+  static final field dynamic _redirecting# = <dynamic>[#C4]/*isLegacy*/;
+  constructor _([core::int? field = #C5]) → self::Class4
+    : self::Class4::field = field, super core::Object::•()
+    ;
+  static method _#_#tearOff([core::int? field = #C5]) → self::Class4
+    return new self::Class4::_(field);
+  static factory •([core::int? field = #C5]) → self::Class4
+    return new self::Class4::_(field);
+  static method _#new#tearOff([core::int? field = #C5]) → self::Class4
+    return new self::Class4::_(field);
+}
+class Class5 extends core::Object {
+  final field core::int field1;
+  final field core::int? field2;
+  static final field dynamic _redirecting# = <dynamic>[#C6]/*isLegacy*/;
+  constructor _(core::int field1, [core::int? field2 = #C5]) → self::Class5
+    : self::Class5::field1 = field1, self::Class5::field2 = field2, super core::Object::•()
+    ;
+  static method _#_#tearOff(core::int field1, [core::int? field2 = #C5]) → self::Class5
+    return new self::Class5::_(field1, field2);
+  static factory •(core::int field1, [core::int? field2 = #C5]) → self::Class5
+    return new self::Class5::_(field1, field2);
+  static method _#new#tearOff(core::int field1, [core::int? field2 = #C5]) → self::Class5
+    return new self::Class5::_(field1, field2);
+}
+class Class6 extends core::Object {
+  final field core::int field1;
+  final field core::int? field2;
+  final field core::int field3;
+  static final field dynamic _redirecting# = <dynamic>[#C7]/*isLegacy*/;
+  constructor _(core::int field1, {core::int? field2 = #C5, required core::int field3 = #C5}) → self::Class6
+    : self::Class6::field1 = field1, self::Class6::field2 = field2, self::Class6::field3 = field3, super core::Object::•()
+    ;
+  static method _#_#tearOff(core::int field1, {core::int? field2 = #C5, required core::int field3 = #C5}) → self::Class6
+    return new self::Class6::_(field1, field2: field2, field3: field3);
+  static factory •(core::int field1, {core::int? field2 = #C5, required core::int field3 = #C5}) → self::Class6
+    return new self::Class6::_(field1, field2: field2, field3: field3);
+  static method _#new#tearOff(core::int field1, {core::int? field2 = #C5, required core::int field3 = #C5}) → self::Class6
+    return new self::Class6::_(field1, field2: field2, field3: field3);
+}
+class Class7a extends core::Object implements self::Class7b {
+  constructor •() → self::Class7a
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff() → self::Class7a
+    return new self::Class7a::•();
+}
+class Class7b extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C8]/*isLegacy*/;
+  static factory •() → self::Class7b
+    return new self::Class7a::•();
+  static method _#new#tearOff() → self::Class7b
+    return new self::Class7a::•();
+}
+class Class8a<T extends core::Object? = dynamic> extends core::Object implements self::Class8b<self::Class8a::T%> {
+  constructor •() → self::Class8a<self::Class8a::T%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::Class8a<self::Class8a::_#new#tearOff::T%>
+    return new self::Class8a::•<self::Class8a::_#new#tearOff::T%>();
+  static factory fact<T extends core::Object? = dynamic>() → self::Class8a<self::Class8a::fact::T%>
+    return new self::Class8a::•<self::Class8a::fact::T%>();
+  static method _#fact#tearOff<T extends core::Object? = dynamic>() → self::Class8a<self::Class8a::_#fact#tearOff::T%>
+    return self::Class8a::fact<self::Class8a::_#fact#tearOff::T%>();
+}
+class Class8b<T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C9, #C10]/*isLegacy*/;
+  static factory •<T extends core::Object? = dynamic>() → self::Class8b<self::Class8b::•::T%>
+    return new self::Class8a::•<self::Class8b::•::T%>();
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::Class8b<self::Class8b::_#new#tearOff::T%>
+    return new self::Class8a::•<self::Class8b::_#new#tearOff::T%>();
+  static factory fact<T extends core::Object? = dynamic>() → self::Class8b<self::Class8b::fact::T%>
+    return self::Class8a::fact<self::Class8b::fact::T%>();
+  static method _#fact#tearOff<T extends core::Object? = dynamic>() → self::Class8b<self::Class8b::_#fact#tearOff::T%>
+    return self::Class8a::fact<self::Class8b::_#fact#tearOff::T%>();
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static method main() → dynamic {
+  core::print("inSoundMode: ${self::inSoundMode}");
+  self::testNoArgs();
+  self::testArgs();
+}
+static method testNoArgs() → dynamic {
+  () → self::Class1 f1a = #C11;
+  self::Class1 c1a = f1a(){() → self::Class1};
+  self::expect(true, c1a is{ForNonNullableByDefault} self::Class1);
+  dynamic f1b = #C11;
+  dynamic c1b = f1b{dynamic}.call();
+  self::expect(true, c1b is{ForNonNullableByDefault} self::Class1);
+  self::expect(true, core::identical(f1a, f1b));
+  () → self::Class2 f2a = #C12;
+  self::Class2 c2a = f2a(){() → self::Class2};
+  self::expect(true, c2a is{ForNonNullableByDefault} self::Class2);
+  dynamic f2b = #C12;
+  dynamic c2b = f2b{dynamic}.call();
+  self::expect(true, c2b is{ForNonNullableByDefault} self::Class2);
+  self::expect(true, core::identical(f2a, f2b));
+}
+static method testArgs() → dynamic {
+  (core::int) → self::Class3 f3a = #C13;
+  self::Class3 c3a = f3a(42){(core::int) → self::Class3};
+  self::expect(42, c3a.{self::Class3::field}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:101:8: Error: Too few positional arguments: 1 required, 0 given.
+    f3a(); // error
+       ^" in f3a{<inapplicable>}.();
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:102:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f3a(42, 87); // error
+       ^" in f3a{<inapplicable>}.(42, 87);
+  };
+  dynamic f3b = #C13;
+  dynamic c3b = f3b{dynamic}.call(87);
+  self::expect(87, c3b{dynamic}.field);
+  self::throws(() → dynamic => f3b{dynamic}.call());
+  self::throws(() → dynamic => f3b{dynamic}.call(42, 87));
+  ([core::int?]) → self::Class4 f4a = #C14;
+  self::Class4 c4a = f4a(){([core::int?]) → self::Class4};
+  self::expect(null, c4a.{self::Class4::field}{core::int?});
+  self::Class4 c4b = f4a(42){([core::int?]) → self::Class4};
+  self::expect(42, c4b.{self::Class4::field}{core::int?});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:117:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f4a(42, 87); // error
+       ^" in f4a{<inapplicable>}.(42, 87);
+  };
+  dynamic f4b = #C14;
+  self::throws(() → dynamic => f4b{dynamic}.call(42, 87));
+  (core::int, [core::int?]) → self::Class5 f5a = #C15;
+  self::Class5 c5a = f5a(42){(core::int, [core::int?]) → self::Class5};
+  self::expect(42, c5a.{self::Class5::field1}{core::int});
+  self::expect(null, c5a.{self::Class5::field2}{core::int?});
+  self::Class5 c5b = f5a(87, 42){(core::int, [core::int?]) → self::Class5};
+  self::expect(87, c5b.{self::Class5::field1}{core::int});
+  self::expect(42, c5b.{self::Class5::field2}{core::int?});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:131:8: Error: Too few positional arguments: 1 required, 0 given.
+    f5a(); // error
+       ^" in f5a{<inapplicable>}.();
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:132:8: Error: Too many positional arguments: 2 allowed, but 3 found.
+Try removing the extra positional arguments.
+    f5a(42, 87, 123); // error
+       ^" in f5a{<inapplicable>}.(42, 87, 123);
+  };
+  dynamic f5b = #C15;
+  self::throws(() → dynamic => f5b{dynamic}.call());
+  self::throws(() → dynamic => f5b{dynamic}.call(42, 87, 123));
+  (core::int, {field2: core::int?, required field3: core::int}) → self::Class6 f6a = #C16;
+  self::Class6 c6a = f6a(42, field3: 87){(core::int, {field2: core::int?, required field3: core::int}) → self::Class6};
+  self::expect(42, c6a.{self::Class6::field1}{core::int});
+  self::expect(null, c6a.{self::Class6::field2}{core::int?});
+  self::expect(87, c6a.{self::Class6::field3}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:144:8: Error: Too few positional arguments: 1 required, 0 given.
+    f6a(); // error
+       ^" in f6a{<inapplicable>}.();
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:145:8: Error: Required named parameter 'field3' must be provided.
+    f6a(42); // error
+       ^" in f6a{<inapplicable>}.(42);
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:146:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f6a(42, 87); // error
+       ^" in f6a{<inapplicable>}.(42, 87);
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off.dart:147:8: Error: Too few positional arguments: 1 required, 0 given.
+    f6a(field1: 87, field2: 87); // error
+       ^" in f6a{<inapplicable>}.(field1: 87, field2: 87);
+  };
+  self::Class6 c6b = f6a(42, field2: 123, field3: 87){(core::int, {field2: core::int?, required field3: core::int}) → self::Class6};
+  self::expect(42, c6b.{self::Class6::field1}{core::int});
+  self::expect(123, c6b.{self::Class6::field2}{core::int?});
+  self::expect(87, c6b.{self::Class6::field3}{core::int});
+  self::Class6 c6c = f6a(87, field3: 42, field2: 123){(core::int, {field2: core::int?, required field3: core::int}) → self::Class6};
+  self::expect(87, c6c.{self::Class6::field1}{core::int});
+  self::expect(123, c6c.{self::Class6::field2}{core::int?});
+  self::expect(42, c6c.{self::Class6::field3}{core::int});
+  dynamic f6b = #C16;
+  self::throws(() → dynamic => f6b{dynamic}.call());
+  self::throws(() → dynamic => f6b{dynamic}.call(42), inSoundModeOnly: true);
+  self::throws(() → dynamic => f6b{dynamic}.call(42, 87), inSoundModeOnly: true);
+  self::throws(() → dynamic => f6b{dynamic}.call(field1: 87, field2: 87));
+  () → self::Class7b f7a = #C17;
+  self::Class7b c7a = f7a(){() → self::Class7b};
+  self::expect(true, c7a is{ForNonNullableByDefault} self::Class7a);
+  self::expect(true, c7a is{ForNonNullableByDefault} self::Class7b);
+  <T extends core::Object? = dynamic>() → self::Class8b<T%> f8a = #C18;
+  self::Class8b<dynamic> c8a = f8a<dynamic>(){() → self::Class8b<dynamic>};
+  self::expect(true, c8a is{ForNonNullableByDefault} self::Class8a<dynamic>);
+  self::expect(true, c8a is{ForNonNullableByDefault} self::Class8b<dynamic>);
+  self::Class8b<core::int> c8b = f8a<core::int>(){() → self::Class8b<core::int>};
+  self::expect(true, c8b is{ForNonNullableByDefault} self::Class8a<core::int>);
+  self::expect(true, c8b is{ForNonNullableByDefault} self::Class8b<core::int>);
+  self::expect(false, c8b is{ForNonNullableByDefault} self::Class8b<core::String>);
+  <T extends core::Object? = dynamic>() → self::Class8b<T%> f8b = #C19;
+  self::Class8b<dynamic> c8c = f8b<dynamic>(){() → self::Class8b<dynamic>};
+  self::expect(true, c8c is{ForNonNullableByDefault} self::Class8a<dynamic>);
+  self::expect(true, c8c is{ForNonNullableByDefault} self::Class8b<dynamic>);
+  self::Class8b<core::int> c8d = f8b<core::int>(){() → self::Class8b<core::int>};
+  self::expect(true, c8d is{ForNonNullableByDefault} self::Class8a<core::int>);
+  self::expect(true, c8d is{ForNonNullableByDefault} self::Class8b<core::int>);
+  self::expect(false, c8d is{ForNonNullableByDefault} self::Class8b<core::String>);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, {core::bool inSoundModeOnly = #C20}) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print("Thrown: ${e}");
+    return;
+  }
+  if(!self::inSoundMode && inSoundModeOnly) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+constants  {
+  #C1 = constructor-tearoff self::Class1::•
+  #C2 = constructor-tearoff self::Class2::named
+  #C3 = constructor-tearoff self::Class3::•
+  #C4 = constructor-tearoff self::Class4::•
+  #C5 = null
+  #C6 = constructor-tearoff self::Class5::•
+  #C7 = constructor-tearoff self::Class6::•
+  #C8 = constructor-tearoff self::Class7b::•
+  #C9 = constructor-tearoff self::Class8b::•
+  #C10 = constructor-tearoff self::Class8b::fact
+  #C11 = static-tearoff self::Class1::_#new#tearOff
+  #C12 = static-tearoff self::Class2::_#named#tearOff
+  #C13 = static-tearoff self::Class3::_#new#tearOff
+  #C14 = static-tearoff self::Class4::_#new#tearOff
+  #C15 = static-tearoff self::Class5::_#new#tearOff
+  #C16 = static-tearoff self::Class6::_#new#tearOff
+  #C17 = static-tearoff self::Class7b::_#new#tearOff
+  #C18 = static-tearoff self::Class8b::_#new#tearOff
+  #C19 = static-tearoff self::Class8b::_#fact#tearOff
+  #C20 = false
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values.dart.weak.modular.expect
new file mode 100644
index 0000000..8c398fe
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values.dart.weak.modular.expect
@@ -0,0 +1,111 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values.dart:33:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f1a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values.dart:49:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//     f2a(87); // error
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  final field core::int field;
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor _([core::int field = #C2]) → self::Class1
+    : self::Class1::field = field, super core::Object::•()
+    ;
+  static method _#_#tearOff([core::int field = #C2]) → self::Class1
+    return new self::Class1::_(field);
+  static factory •([core::int field = #C3]) → self::Class1
+    return new self::Class1::_(field);
+  static method _#new#tearOff([core::int field = #C2]) → self::Class1
+    return new self::Class1::_(field);
+}
+class Class2 extends core::Object {
+  final field core::int field;
+  static final field dynamic _redirecting# = <dynamic>[#C4]/*isLegacy*/;
+  constructor _({core::int field = #C2}) → self::Class2
+    : self::Class2::field = field, super core::Object::•()
+    ;
+  static method _#_#tearOff({core::int field = #C2}) → self::Class2
+    return new self::Class2::_(field: field);
+  static factory •({core::int field = #C3}) → self::Class2
+    return new self::Class2::_(field: field);
+  static method _#new#tearOff({core::int field = #C2}) → self::Class2
+    return new self::Class2::_(field: field);
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static method main() → dynamic {
+  core::print("inSoundMode: ${self::inSoundMode}");
+  self::testDefaultValues();
+}
+static method testDefaultValues() → void {
+  ([core::int]) → self::Class1 f1a = #C5;
+  self::Class1 c1a = f1a(){([core::int]) → self::Class1};
+  self::expect(42, c1a.{self::Class1::field}{core::int});
+  self::Class1 c1b = f1a(87){([core::int]) → self::Class1};
+  self::expect(87, c1b.{self::Class1::field}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values.dart:33:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f1a(42, 87); // error
+       ^" in f1a{<inapplicable>}.(42, 87);
+  };
+  dynamic f1b = #C5;
+  dynamic c1c = f1b{dynamic}.call();
+  self::expect(42, c1c{dynamic}.field);
+  dynamic c1d = f1b{dynamic}.call(87);
+  self::expect(87, c1d{dynamic}.field);
+  self::throws(() → dynamic => f1b{dynamic}.call(42, 87));
+  ({field: core::int}) → self::Class2 f2a = #C6;
+  self::Class2 c2a = f2a(){({field: core::int}) → self::Class2};
+  self::expect(42, c2a.{self::Class2::field}{core::int});
+  self::Class2 c2b = f2a(field: 87){({field: core::int}) → self::Class2};
+  self::expect(87, c2b.{self::Class2::field}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values.dart:49:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+    f2a(87); // error
+       ^" in f2a{<inapplicable>}.(87);
+  };
+  dynamic f2b = #C6;
+  dynamic c2c = f2b{dynamic}.call();
+  self::expect(42, c2c{dynamic}.field);
+  dynamic c2d = f2b{dynamic}.call(field: 87);
+  self::expect(87, c2d{dynamic}.field);
+  self::throws(() → dynamic => f2b{dynamic}.call(87));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, {core::bool inSoundModeOnly = #C7}) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print("Thrown: ${e}");
+    return;
+  }
+  if(!self::inSoundMode && inSoundModeOnly) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+constants  {
+  #C1 = constructor-tearoff self::Class1::•
+  #C2 = 42
+  #C3 = null
+  #C4 = constructor-tearoff self::Class2::•
+  #C5 = static-tearoff self::Class1::_#new#tearOff
+  #C6 = static-tearoff self::Class2::_#new#tearOff
+  #C7 = false
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values.dart.weak.outline.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values.dart.weak.outline.expect
index 20f744e..a220416 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values.dart.weak.outline.expect
@@ -5,7 +5,7 @@
 class Class1 extends core::Object {
   final field core::int field;
   static final field dynamic _redirecting# = <dynamic>[self::Class1::•]/*isLegacy*/;
-  constructor _([core::int field]) → self::Class1
+  constructor _([core::int field = 42]) → self::Class1
     ;
   static method _#_#tearOff([core::int field]) → self::Class1
     return new self::Class1::_(field);
@@ -17,7 +17,7 @@
 class Class2 extends core::Object {
   final field core::int field;
   static final field dynamic _redirecting# = <dynamic>[self::Class2::•]/*isLegacy*/;
-  constructor _({core::int field}) → self::Class2
+  constructor _({core::int field = 42}) → self::Class2
     ;
   static method _#_#tearOff({core::int field}) → self::Class2
     return new self::Class2::_(field: field);
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart.weak.modular.expect
new file mode 100644
index 0000000..aa8c2df
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart.weak.modular.expect
@@ -0,0 +1,244 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:58:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f1b(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:66:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//     f1c(42); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:67:8: Error: Too many positional arguments: 0 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f1c(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:112:21: Error: No named parameter with the name 'field2'.
+//     f2c(field1: 42, field2: 87); // error
+//                     ^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:123:9: Error: No named parameter with the name 'field1'.
+//     f2d(field1: 42, field2: 87); // error
+//         ^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:131:9: Error: No named parameter with the name 'field1'.
+//     f2e(field1: 42); // error
+//         ^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:132:9: Error: No named parameter with the name 'field2'.
+//     f2e(field2: 87); // error
+//         ^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:133:9: Error: No named parameter with the name 'field1'.
+//     f2e(field1: 42, field2: 87); // error
+//         ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  final field core::int field1;
+  final field core::int field2;
+  static final field dynamic _redirecting# = <dynamic>[#C1, #C2, #C3, #C4, #C5, #C6, #C7, #C8]/*isLegacy*/;
+  constructor positional([core::int field1 = #C9, core::int field2 = #C10]) → self::Class1
+    : self::Class1::field1 = field1, self::Class1::field2 = field2, super core::Object::•()
+    ;
+  constructor named({core::int field1 = #C9, core::int field2 = #C10}) → self::Class1
+    : self::Class1::field1 = field1, self::Class1::field2 = field2, super core::Object::•()
+    ;
+  static method _#positional#tearOff([core::int field1 = #C9, core::int field2 = #C10]) → self::Class1
+    return new self::Class1::positional(field1, field2);
+  static factory redirectPositionalSame([core::int field1 = #C11, core::int field2 = #C11]) → self::Class1
+    return new self::Class1::positional(field1, field2);
+  static method _#redirectPositionalSame#tearOff([core::int field1 = #C9, core::int field2 = #C10]) → self::Class1
+    return new self::Class1::positional(field1, field2);
+  static factory redirectPositionalFewer1([core::int field1 = #C11]) → self::Class1
+    return new self::Class1::positional(field1);
+  static method _#redirectPositionalFewer1#tearOff([core::int field1 = #C9]) → self::Class1
+    return new self::Class1::positional(field1);
+  static factory redirectPositionalFewer2() → self::Class1
+    return new self::Class1::positional();
+  static method _#redirectPositionalFewer2#tearOff() → self::Class1
+    return new self::Class1::positional();
+  static method _#named#tearOff({core::int field1 = #C9, core::int field2 = #C10}) → self::Class1
+    return new self::Class1::named(field1: field1, field2: field2);
+  static factory redirectNamedSame({core::int field1 = #C11, core::int field2 = #C11}) → self::Class1
+    return new self::Class1::named(field1: field1, field2: field2);
+  static method _#redirectNamedSame#tearOff({core::int field1 = #C9, core::int field2 = #C10}) → self::Class1
+    return new self::Class1::named(field1: field1, field2: field2);
+  static factory redirectNamedReorder({core::int field2 = #C11, core::int field1 = #C11}) → self::Class1
+    return new self::Class1::named(field2: field2, field1: field1);
+  static method _#redirectNamedReorder#tearOff({core::int field2 = #C10, core::int field1 = #C9}) → self::Class1
+    return new self::Class1::named(field2: field2, field1: field1);
+  static factory redirectNamedFewer1({core::int field1 = #C11}) → self::Class1
+    return new self::Class1::named(field1: field1);
+  static method _#redirectNamedFewer1#tearOff({core::int field1 = #C9}) → self::Class1
+    return new self::Class1::named(field1: field1);
+  static factory redirectNamedFewer2({core::int field2 = #C11}) → self::Class1
+    return new self::Class1::named(field2: field2);
+  static method _#redirectNamedFewer2#tearOff({core::int field2 = #C10}) → self::Class1
+    return new self::Class1::named(field2: field2);
+  static factory redirectNamedFewer3() → self::Class1
+    return new self::Class1::named();
+  static method _#redirectNamedFewer3#tearOff() → self::Class1
+    return new self::Class1::named();
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static method main() → dynamic {
+  core::print("inSoundMode: ${self::inSoundMode}");
+  self::testDefaultValues();
+}
+static method testDefaultValues() → dynamic {
+  ([core::int, core::int]) → self::Class1 f1a = #C12;
+  self::Class1 c1a = f1a(){([core::int, core::int]) → self::Class1};
+  self::expect(1, c1a.{self::Class1::field1}{core::int});
+  self::expect(2, c1a.{self::Class1::field2}{core::int});
+  self::Class1 c1b = f1a(42){([core::int, core::int]) → self::Class1};
+  self::expect(42, c1b.{self::Class1::field1}{core::int});
+  self::expect(2, c1b.{self::Class1::field2}{core::int});
+  self::Class1 c1c = f1a(42, 87){([core::int, core::int]) → self::Class1};
+  self::expect(42, c1c.{self::Class1::field1}{core::int});
+  self::expect(87, c1c.{self::Class1::field2}{core::int});
+  ([core::int]) → self::Class1 f1b = #C13;
+  self::Class1 c1d = f1b(){([core::int]) → self::Class1};
+  self::expect(1, c1d.{self::Class1::field1}{core::int});
+  self::expect(2, c1d.{self::Class1::field2}{core::int});
+  self::Class1 c1e = f1b(42){([core::int]) → self::Class1};
+  self::expect(42, c1e.{self::Class1::field1}{core::int});
+  self::expect(2, c1e.{self::Class1::field2}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:58:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f1b(42, 87); // error
+       ^" in f1b{<inapplicable>}.(42, 87);
+  };
+  () → self::Class1 f1c = #C14;
+  self::Class1 c1f = f1c(){() → self::Class1};
+  self::expect(1, c1f.{self::Class1::field1}{core::int});
+  self::expect(2, c1f.{self::Class1::field2}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:66:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+    f1c(42); // error
+       ^" in f1c{<inapplicable>}.(42);
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:67:8: Error: Too many positional arguments: 0 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f1c(42, 87); // error
+       ^" in f1c{<inapplicable>}.(42, 87);
+  };
+  ({field1: core::int, field2: core::int}) → self::Class1 f2a = #C15;
+  self::Class1 c2a = f2a(){({field1: core::int, field2: core::int}) → self::Class1};
+  self::expect(1, c2a.{self::Class1::field1}{core::int});
+  self::expect(2, c2a.{self::Class1::field2}{core::int});
+  self::Class1 c2b = f2a(field1: 42){({field1: core::int, field2: core::int}) → self::Class1};
+  self::expect(42, c2b.{self::Class1::field1}{core::int});
+  self::expect(2, c2b.{self::Class1::field2}{core::int});
+  self::Class1 c2c = f2a(field1: 42, field2: 87){({field1: core::int, field2: core::int}) → self::Class1};
+  self::expect(42, c2c.{self::Class1::field1}{core::int});
+  self::expect(87, c2c.{self::Class1::field2}{core::int});
+  self::Class1 c2d = f2a(field2: 87){({field1: core::int, field2: core::int}) → self::Class1};
+  self::expect(1, c2d.{self::Class1::field1}{core::int});
+  self::expect(87, c2d.{self::Class1::field2}{core::int});
+  self::Class1 c2e = f2a(field2: 87, field1: 42){({field1: core::int, field2: core::int}) → self::Class1};
+  self::expect(42, c2e.{self::Class1::field1}{core::int});
+  self::expect(87, c2e.{self::Class1::field2}{core::int});
+  ({field1: core::int, field2: core::int}) → self::Class1 f2b = #C16;
+  self::Class1 c3a = f2b(){({field1: core::int, field2: core::int}) → self::Class1};
+  self::expect(1, c3a.{self::Class1::field1}{core::int});
+  self::expect(2, c3a.{self::Class1::field2}{core::int});
+  self::Class1 c3b = f2b(field1: 42){({field1: core::int, field2: core::int}) → self::Class1};
+  self::expect(42, c3b.{self::Class1::field1}{core::int});
+  self::expect(2, c3b.{self::Class1::field2}{core::int});
+  self::Class1 c3c = f2b(field1: 42, field2: 87){({field1: core::int, field2: core::int}) → self::Class1};
+  self::expect(42, c3c.{self::Class1::field1}{core::int});
+  self::expect(87, c3c.{self::Class1::field2}{core::int});
+  self::Class1 c3d = f2b(field2: 87){({field1: core::int, field2: core::int}) → self::Class1};
+  self::expect(1, c3d.{self::Class1::field1}{core::int});
+  self::expect(87, c3d.{self::Class1::field2}{core::int});
+  self::Class1 c3e = f2b(field2: 87, field1: 42){({field1: core::int, field2: core::int}) → self::Class1};
+  self::expect(42, c3e.{self::Class1::field1}{core::int});
+  self::expect(87, c3e.{self::Class1::field2}{core::int});
+  ({field1: core::int}) → self::Class1 f2c = #C17;
+  self::Class1 c4a = f2c(){({field1: core::int}) → self::Class1};
+  self::expect(1, c4a.{self::Class1::field1}{core::int});
+  self::expect(2, c4a.{self::Class1::field2}{core::int});
+  self::Class1 c4b = f2c(field1: 42){({field1: core::int}) → self::Class1};
+  self::expect(42, c4b.{self::Class1::field1}{core::int});
+  self::expect(2, c4b.{self::Class1::field2}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:112:21: Error: No named parameter with the name 'field2'.
+    f2c(field1: 42, field2: 87); // error
+                    ^^^^^^" in f2c{<inapplicable>}.(field1: 42, field2: 87);
+  };
+  ({field2: core::int}) → self::Class1 f2d = #C18;
+  self::Class1 c5a = f2d(){({field2: core::int}) → self::Class1};
+  self::expect(1, c5a.{self::Class1::field1}{core::int});
+  self::expect(2, c5a.{self::Class1::field2}{core::int});
+  self::Class1 c5b = f2d(field2: 87){({field2: core::int}) → self::Class1};
+  self::expect(1, c5b.{self::Class1::field1}{core::int});
+  self::expect(87, c5b.{self::Class1::field2}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:123:9: Error: No named parameter with the name 'field1'.
+    f2d(field1: 42, field2: 87); // error
+        ^^^^^^" in f2d{<inapplicable>}.(field1: 42, field2: 87);
+  };
+  () → self::Class1 f2e = #C19;
+  self::Class1 c6a = f2e(){() → self::Class1};
+  self::expect(1, c6a.{self::Class1::field1}{core::int});
+  self::expect(2, c6a.{self::Class1::field2}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:131:9: Error: No named parameter with the name 'field1'.
+    f2e(field1: 42); // error
+        ^^^^^^" in f2e{<inapplicable>}.(field1: 42);
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:132:9: Error: No named parameter with the name 'field2'.
+    f2e(field2: 87); // error
+        ^^^^^^" in f2e{<inapplicable>}.(field2: 87);
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart:133:9: Error: No named parameter with the name 'field1'.
+    f2e(field1: 42, field2: 87); // error
+        ^^^^^^" in f2e{<inapplicable>}.(field1: 42, field2: 87);
+  };
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, {core::bool inSoundModeOnly = #C20}) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print("Thrown: ${e}");
+    return;
+  }
+  if(!self::inSoundMode && inSoundModeOnly) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+constants  {
+  #C1 = constructor-tearoff self::Class1::redirectPositionalSame
+  #C2 = constructor-tearoff self::Class1::redirectPositionalFewer1
+  #C3 = constructor-tearoff self::Class1::redirectPositionalFewer2
+  #C4 = constructor-tearoff self::Class1::redirectNamedSame
+  #C5 = constructor-tearoff self::Class1::redirectNamedReorder
+  #C6 = constructor-tearoff self::Class1::redirectNamedFewer1
+  #C7 = constructor-tearoff self::Class1::redirectNamedFewer2
+  #C8 = constructor-tearoff self::Class1::redirectNamedFewer3
+  #C9 = 1
+  #C10 = 2
+  #C11 = null
+  #C12 = static-tearoff self::Class1::_#redirectPositionalSame#tearOff
+  #C13 = static-tearoff self::Class1::_#redirectPositionalFewer1#tearOff
+  #C14 = static-tearoff self::Class1::_#redirectPositionalFewer2#tearOff
+  #C15 = static-tearoff self::Class1::_#redirectNamedSame#tearOff
+  #C16 = static-tearoff self::Class1::_#redirectNamedReorder#tearOff
+  #C17 = static-tearoff self::Class1::_#redirectNamedFewer1#tearOff
+  #C18 = static-tearoff self::Class1::_#redirectNamedFewer2#tearOff
+  #C19 = static-tearoff self::Class1::_#redirectNamedFewer3#tearOff
+  #C20 = false
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart.weak.outline.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart.weak.outline.expect
index 7cf24c4..d465217 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/redirecting_factory_tear_off_default_values_complex.dart.weak.outline.expect
@@ -6,9 +6,9 @@
   final field core::int field1;
   final field core::int field2;
   static final field dynamic _redirecting# = <dynamic>[self::Class1::redirectPositionalSame, self::Class1::redirectPositionalFewer1, self::Class1::redirectPositionalFewer2, self::Class1::redirectNamedSame, self::Class1::redirectNamedReorder, self::Class1::redirectNamedFewer1, self::Class1::redirectNamedFewer2, self::Class1::redirectNamedFewer3]/*isLegacy*/;
-  constructor positional([core::int field1, core::int field2]) → self::Class1
+  constructor positional([core::int field1 = 1, core::int field2 = 2]) → self::Class1
     ;
-  constructor named({core::int field1, core::int field2}) → self::Class1
+  constructor named({core::int field1 = 1, core::int field2 = 2}) → self::Class1
     ;
   static method _#positional#tearOff([core::int field1, core::int field2]) → self::Class1
     return new self::Class1::positional(field1, field2);
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_from.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_from.dart.weak.modular.expect
new file mode 100644
index 0000000..01b742d
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_from.dart.weak.modular.expect
@@ -0,0 +1,126 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///typedef_from_lib.dart";
+
+part typedef_from_part.dart;
+typedef B<S extends core::Object? = dynamic> = self::Class<S%, core::int>;
+class Class<S extends core::Object? = dynamic, T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor •(self::Class::S% a, self::Class::T% b) → self::Class<self::Class::S%, self::Class::T%>
+    : super core::Object::•()
+    ;
+  constructor named(self::Class::S% a, [self::Class::T? b = #C2, core::int c = #C3]) → self::Class<self::Class::S%, self::Class::T%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<S extends core::Object? = dynamic, T extends core::Object? = dynamic>(self::Class::_#new#tearOff::S% a, self::Class::_#new#tearOff::T% b) → self::Class<self::Class::_#new#tearOff::S%, self::Class::_#new#tearOff::T%>
+    return new self::Class::•<self::Class::_#new#tearOff::S%, self::Class::_#new#tearOff::T%>(a, b);
+  static method _#named#tearOff<S extends core::Object? = dynamic, T extends core::Object? = dynamic>(self::Class::_#named#tearOff::S% a, [self::Class::_#named#tearOff::T? b = #C2, core::int c = #C3]) → self::Class<self::Class::_#named#tearOff::S%, self::Class::_#named#tearOff::T%>
+    return new self::Class::named<self::Class::_#named#tearOff::S%, self::Class::_#named#tearOff::T%>(a, b, c);
+  static factory fact<S extends core::Object? = dynamic, T extends core::Object? = dynamic>(self::Class::fact::S% a, {self::Class::fact::T? b = #C2, core::int c = #C3}) → self::Class<self::Class::fact::S%, self::Class::fact::T%>
+    return new self::Class::named<self::Class::fact::S%, self::Class::fact::T%>(a, b, c);
+  static method _#fact#tearOff<S extends core::Object? = dynamic, T extends core::Object? = dynamic>(self::Class::_#fact#tearOff::S% a, {self::Class::_#fact#tearOff::T? b = #C2, core::int c = #C3}) → self::Class<self::Class::_#fact#tearOff::S%, self::Class::_#fact#tearOff::T%>
+    return self::Class::fact<self::Class::_#fact#tearOff::S%, self::Class::_#fact#tearOff::T%>(a, b: b, c: c);
+  static factory redirect<S extends core::Object? = dynamic, T extends core::Object? = dynamic>(self::Class::redirect::S% a) → self::Class<self::Class::redirect::S%, self::Class::redirect::T%>
+    return new self::Class::named<self::Class::redirect::S%, self::Class::redirect::T%>(a);
+  static method _#redirect#tearOff<S extends core::Object? = dynamic, T extends core::Object? = dynamic>(self::Class::_#redirect#tearOff::S% a) → self::Class<self::Class::_#redirect#tearOff::S%, self::Class::_#redirect#tearOff::T%>
+    return new self::Class::named<self::Class::_#redirect#tearOff::S%, self::Class::_#redirect#tearOff::T%>(a);
+}
+static method main() → dynamic {
+  <T extends core::Object? = dynamic>(T%, core::String) → self::Class<T%, core::String> aNew = #C4;
+  <T extends core::Object? = dynamic>(T%, [core::String?, core::int]) → self::Class<T%, core::String> aNamed = #C5;
+  <T extends core::Object? = dynamic>(T%, {b: core::String?, c: core::int}) → self::Class<T%, core::String> aFact = #C6;
+  <T extends core::Object? = dynamic>(T%) → self::Class<T%, core::String> aRedirect = #C7;
+  aNew<core::String>("", ""){(core::String, core::String) → self::Class<core::String, core::String>};
+  aNew<core::int>(0, ""){(core::int, core::String) → self::Class<core::int, core::String>};
+  aNamed<core::String>(""){(core::String, [core::String?, core::int]) → self::Class<core::String, core::String>};
+  aNamed<core::int>(0, ""){(core::int, [core::String?, core::int]) → self::Class<core::int, core::String>};
+  aNamed<core::String>("", "", 87){(core::String, [core::String?, core::int]) → self::Class<core::String, core::String>};
+  aFact<core::int>(0){(core::int, {b: core::String?, c: core::int}) → self::Class<core::int, core::String>};
+  aFact<core::String>("", b: ""){(core::String, {b: core::String?, c: core::int}) → self::Class<core::String, core::String>};
+  aFact<core::int>(0, c: 87){(core::int, {b: core::String?, c: core::int}) → self::Class<core::int, core::String>};
+  aFact<core::String>("", c: 87, b: ""){(core::String, {b: core::String?, c: core::int}) → self::Class<core::String, core::String>};
+  aRedirect<core::String>(""){(core::String) → self::Class<core::String, core::String>};
+  aRedirect<core::int>(0){(core::int) → self::Class<core::int, core::String>};
+  (core::bool, core::String) → self::Class<core::bool, core::String> aNewInst = aNew<core::bool>;
+  (core::bool, [core::String?, core::int]) → self::Class<core::bool, core::String> aNamedInst = aNamed<core::bool>;
+  (core::bool, {b: core::String?, c: core::int}) → self::Class<core::bool, core::String> aFactInst = aFact<core::bool>;
+  (core::bool) → self::Class<core::bool, core::String> aRedirectInst = aRedirect<core::bool>;
+  aNewInst(true, ""){(core::bool, core::String) → self::Class<core::bool, core::String>};
+  aNamedInst(false){(core::bool, [core::String?, core::int]) → self::Class<core::bool, core::String>};
+  aNamedInst(true, ""){(core::bool, [core::String?, core::int]) → self::Class<core::bool, core::String>};
+  aNamedInst(false, "", 87){(core::bool, [core::String?, core::int]) → self::Class<core::bool, core::String>};
+  aFactInst(true){(core::bool, {b: core::String?, c: core::int}) → self::Class<core::bool, core::String>};
+  aFactInst(false, b: ""){(core::bool, {b: core::String?, c: core::int}) → self::Class<core::bool, core::String>};
+  aFactInst(true, c: 87){(core::bool, {b: core::String?, c: core::int}) → self::Class<core::bool, core::String>};
+  aFactInst(false, c: 87, b: ""){(core::bool, {b: core::String?, c: core::int}) → self::Class<core::bool, core::String>};
+  aRedirectInst(true){(core::bool) → self::Class<core::bool, core::String>};
+  <S extends core::Object? = dynamic>(S%, core::int) → self::Class<S%, core::int> bNew = #C8;
+  <S extends core::Object? = dynamic>(S%, [core::int?, core::int]) → self::Class<S%, core::int> bNamed = #C9;
+  <S extends core::Object? = dynamic>(S%, {b: core::int?, c: core::int}) → self::Class<S%, core::int> bFact = #C10;
+  <S extends core::Object? = dynamic>(S%) → self::Class<S%, core::int> bRedirect = #C11;
+  bNew<core::String>("", 0){(core::String, core::int) → self::Class<core::String, core::int>};
+  bNew<core::int>(0, 0){(core::int, core::int) → self::Class<core::int, core::int>};
+  bNamed<core::String>(""){(core::String, [core::int?, core::int]) → self::Class<core::String, core::int>};
+  bNamed<core::int>(0, 0){(core::int, [core::int?, core::int]) → self::Class<core::int, core::int>};
+  bNamed<core::String>("", 0, 87){(core::String, [core::int?, core::int]) → self::Class<core::String, core::int>};
+  bFact<core::int>(0){(core::int, {b: core::int?, c: core::int}) → self::Class<core::int, core::int>};
+  bFact<core::String>("", b: 0){(core::String, {b: core::int?, c: core::int}) → self::Class<core::String, core::int>};
+  bFact<core::int>(0, c: 87){(core::int, {b: core::int?, c: core::int}) → self::Class<core::int, core::int>};
+  bFact<core::String>("", c: 87, b: 0){(core::String, {b: core::int?, c: core::int}) → self::Class<core::String, core::int>};
+  bRedirect<core::String>(""){(core::String) → self::Class<core::String, core::int>};
+  bRedirect<core::int>(0){(core::int) → self::Class<core::int, core::int>};
+  (core::bool, core::int) → self::Class<core::bool, core::int> bNewInst = bNew<core::bool>;
+  (core::bool, [core::int?, core::int]) → self::Class<core::bool, core::int> bNamedInst = bNamed<core::bool>;
+  (core::bool, {b: core::int?, c: core::int}) → self::Class<core::bool, core::int> bFactInst = bFact<core::bool>;
+  (core::bool) → self::Class<core::bool, core::int> bRedirectInst = bRedirect<core::bool>;
+  bNewInst(true, 0){(core::bool, core::int) → self::Class<core::bool, core::int>};
+  bNamedInst(false){(core::bool, [core::int?, core::int]) → self::Class<core::bool, core::int>};
+  bNamedInst(true, 0){(core::bool, [core::int?, core::int]) → self::Class<core::bool, core::int>};
+  bNamedInst(false, 0, 87){(core::bool, [core::int?, core::int]) → self::Class<core::bool, core::int>};
+  bFactInst(true){(core::bool, {b: core::int?, c: core::int}) → self::Class<core::bool, core::int>};
+  bFactInst(false, b: 0){(core::bool, {b: core::int?, c: core::int}) → self::Class<core::bool, core::int>};
+  bFactInst(true, c: 87){(core::bool, {b: core::int?, c: core::int}) → self::Class<core::bool, core::int>};
+  bFactInst(false, c: 87, b: 0){(core::bool, {b: core::int?, c: core::int}) → self::Class<core::bool, core::int>};
+  bRedirectInst(true){(core::bool) → self::Class<core::bool, core::int>};
+}
+static method _#B#new#tearOff<S extends core::Object? = dynamic>(self::_#B#new#tearOff::S% a, core::int b) → self::Class<self::_#B#new#tearOff::S%, core::int>
+  return new self::Class::•<self::_#B#new#tearOff::S%, core::int>(a, b);
+static method _#B#named#tearOff<S extends core::Object? = dynamic>(self::_#B#named#tearOff::S% a, [core::int? b = #C2, core::int c = #C3]) → self::Class<self::_#B#named#tearOff::S%, core::int>
+  return new self::Class::named<self::_#B#named#tearOff::S%, core::int>(a, b, c);
+static method _#B#fact#tearOff<S extends core::Object? = dynamic>(self::_#B#fact#tearOff::S% a, {core::int? b = #C2, core::int c = #C3}) → self::Class<self::_#B#fact#tearOff::S%, core::int>
+  return self::Class::fact<self::_#B#fact#tearOff::S%, core::int>(a, b: b, c: c);
+static method _#B#redirect#tearOff<S extends core::Object? = dynamic>(self::_#B#redirect#tearOff::S% a) → self::Class<self::_#B#redirect#tearOff::S%, core::int>
+  return self::Class::_#redirect#tearOff<self::_#B#redirect#tearOff::S%, core::int>(a);
+
+library /*isNonNullableByDefault*/;
+import self as self2;
+import "dart:core" as core;
+import "typedef_from.dart" as self;
+
+import "org-dartlang-testcase:///typedef_from.dart";
+
+typedef A<T extends core::Object? = dynamic> = self::Class<T%, core::String>;
+static method /* from org-dartlang-testcase:///typedef_from.dart */ _#A#new#tearOff<T extends core::Object? = dynamic>(self2::_#A#new#tearOff::T% a, core::String b) → self::Class<self2::_#A#new#tearOff::T%, core::String>
+  return new self::Class::•<self2::_#A#new#tearOff::T%, core::String>(a, b);
+static method /* from org-dartlang-testcase:///typedef_from.dart */ _#A#named#tearOff<T extends core::Object? = dynamic>(self2::_#A#named#tearOff::T% a, [core::String? b = #C2, core::int c = #C3]) → self::Class<self2::_#A#named#tearOff::T%, core::String>
+  return new self::Class::named<self2::_#A#named#tearOff::T%, core::String>(a, b, c);
+static method /* from org-dartlang-testcase:///typedef_from.dart */ _#A#fact#tearOff<T extends core::Object? = dynamic>(self2::_#A#fact#tearOff::T% a, {core::String? b = #C2, core::int c = #C3}) → self::Class<self2::_#A#fact#tearOff::T%, core::String>
+  return self::Class::fact<self2::_#A#fact#tearOff::T%, core::String>(a, b: b, c: c);
+static method /* from org-dartlang-testcase:///typedef_from.dart */ _#A#redirect#tearOff<T extends core::Object? = dynamic>(self2::_#A#redirect#tearOff::T% a) → self::Class<self2::_#A#redirect#tearOff::T%, core::String>
+  return self::Class::_#redirect#tearOff<self2::_#A#redirect#tearOff::T%, core::String>(a);
+
+constants  {
+  #C1 = constructor-tearoff self::Class::redirect
+  #C2 = null
+  #C3 = 42
+  #C4 = static-tearoff self2::_#A#new#tearOff
+  #C5 = static-tearoff self2::_#A#named#tearOff
+  #C6 = static-tearoff self2::_#A#fact#tearOff
+  #C7 = static-tearoff self2::_#A#redirect#tearOff
+  #C8 = static-tearoff self::_#B#new#tearOff
+  #C9 = static-tearoff self::_#B#named#tearOff
+  #C10 = static-tearoff self::_#B#fact#tearOff
+  #C11 = static-tearoff self::_#B#redirect#tearOff
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_from.dart.weak.outline.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_from.dart.weak.outline.expect
index 9f1b30a..757a1e2 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_from.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_from.dart.weak.outline.expect
@@ -10,7 +10,7 @@
   static final field dynamic _redirecting# = <dynamic>[self::Class::redirect]/*isLegacy*/;
   constructor •(self::Class::S% a, self::Class::T% b) → self::Class<self::Class::S%, self::Class::T%>
     ;
-  constructor named(self::Class::S% a, [self::Class::T? b, core::int c]) → self::Class<self::Class::S%, self::Class::T%>
+  constructor named(self::Class::S% a, [self::Class::T? b, core::int c = 42]) → self::Class<self::Class::S%, self::Class::T%>
     ;
   static method _#new#tearOff<S extends core::Object? = dynamic, T extends core::Object? = dynamic>(self::Class::_#new#tearOff::S% a, self::Class::_#new#tearOff::T% b) → self::Class<self::Class::_#new#tearOff::S%, self::Class::_#new#tearOff::T%>
     return new self::Class::•<self::Class::_#new#tearOff::S%, self::Class::_#new#tearOff::T%>(a, b);
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_from_dill/main.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_from_dill/main.dart.weak.modular.expect
new file mode 100644
index 0000000..fa9d121
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_from_dill/main.dart.weak.modular.expect
@@ -0,0 +1,89 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "main_lib.dart" as mai;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+typedef H<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic> = mai::A<Y%>;
+static field dynamic H_new = #C1;
+static field dynamic H_named = #C2;
+static field dynamic H_fact = #C3;
+static field dynamic H_redirect = #C4;
+static field dynamic F_new = #C5;
+static field dynamic F_named = #C6;
+static field dynamic F_fact = #C7;
+static field dynamic F_redirect = #C8;
+static method main() → dynamic {
+  self::expect(true, core::identical(self::F_new, mai::F_new_lib));
+  self::expect(false, core::identical(self::F_new, mai::F_named_lib));
+  self::expect(false, core::identical(self::F_new, mai::F_fact_lib));
+  self::expect(false, core::identical(self::F_new, mai::F_redirect_lib));
+  self::expect(false, core::identical(self::F_new, mai::G_new_lib));
+  self::expect(false, core::identical(self::F_new, mai::G_named_lib));
+  self::expect(false, core::identical(self::F_new, mai::G_fact_lib));
+  self::expect(false, core::identical(self::F_new, mai::G_redirect_lib));
+  self::expect(false, core::identical(self::F_new, self::H_new));
+  self::expect(false, core::identical(self::F_new, self::H_named));
+  self::expect(false, core::identical(self::F_new, self::H_fact));
+  self::expect(false, core::identical(self::F_new, self::H_redirect));
+  self::expect(false, core::identical(self::F_named, mai::F_new_lib));
+  self::expect(true, core::identical(self::F_named, mai::F_named_lib));
+  self::expect(false, core::identical(self::F_named, mai::F_fact_lib));
+  self::expect(false, core::identical(self::F_named, mai::F_redirect_lib));
+  self::expect(false, core::identical(self::F_named, mai::G_new_lib));
+  self::expect(false, core::identical(self::F_named, mai::G_named_lib));
+  self::expect(false, core::identical(self::F_named, mai::G_fact_lib));
+  self::expect(false, core::identical(self::F_named, mai::G_redirect_lib));
+  self::expect(false, core::identical(self::F_named, self::H_new));
+  self::expect(false, core::identical(self::F_named, self::H_named));
+  self::expect(false, core::identical(self::F_named, self::H_fact));
+  self::expect(false, core::identical(self::F_named, self::H_redirect));
+  self::expect(false, core::identical(self::F_fact, mai::F_new_lib));
+  self::expect(false, core::identical(self::F_fact, mai::F_named_lib));
+  self::expect(true, core::identical(self::F_fact, mai::F_fact_lib));
+  self::expect(false, core::identical(self::F_fact, mai::F_redirect_lib));
+  self::expect(false, core::identical(self::F_fact, mai::G_new_lib));
+  self::expect(false, core::identical(self::F_fact, mai::G_named_lib));
+  self::expect(false, core::identical(self::F_fact, mai::G_fact_lib));
+  self::expect(false, core::identical(self::F_fact, mai::G_redirect_lib));
+  self::expect(false, core::identical(self::F_fact, self::H_new));
+  self::expect(false, core::identical(self::F_fact, self::H_named));
+  self::expect(false, core::identical(self::F_fact, self::H_fact));
+  self::expect(false, core::identical(self::F_fact, self::H_redirect));
+  self::expect(false, core::identical(self::F_redirect, mai::F_new_lib));
+  self::expect(false, core::identical(self::F_redirect, mai::F_named_lib));
+  self::expect(false, core::identical(self::F_redirect, mai::F_fact_lib));
+  self::expect(true, core::identical(self::F_redirect, mai::F_redirect_lib));
+  self::expect(false, core::identical(self::F_redirect, mai::G_new_lib));
+  self::expect(false, core::identical(self::F_redirect, mai::G_named_lib));
+  self::expect(false, core::identical(self::F_redirect, mai::G_fact_lib));
+  self::expect(false, core::identical(self::F_redirect, mai::G_redirect_lib));
+  self::expect(false, core::identical(self::F_redirect, self::H_new));
+  self::expect(false, core::identical(self::F_redirect, self::H_named));
+  self::expect(false, core::identical(self::F_redirect, self::H_fact));
+  self::expect(false, core::identical(self::F_redirect, self::H_redirect));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method /* from org-dartlang-testcase:///main_lib.dart */ _#H#fact#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(self::_#H#fact#tearOff::Y% a, {core::int? b, core::int c}) → mai::A<self::_#H#fact#tearOff::Y%>
+  return mai::A::fact<self::_#H#fact#tearOff::Y%>(a, b: b, c: c);
+static method /* from org-dartlang-testcase:///main_lib.dart */ _#H#redirect#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → mai::A<self::_#H#redirect#tearOff::Y%>
+  return mai::A::_#redirect#tearOff<self::_#H#redirect#tearOff::Y%>();
+static method /* from org-dartlang-testcase:///main_lib.dart */ _#H#new#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → mai::A<self::_#H#new#tearOff::Y%>
+  return new mai::A::•<self::_#H#new#tearOff::Y%>();
+static method /* from org-dartlang-testcase:///main_lib.dart */ _#H#named#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(self::_#H#named#tearOff::Y% a, [core::int? b]) → mai::A<self::_#H#named#tearOff::Y%>
+  return new mai::A::named<self::_#H#named#tearOff::Y%>(a, b);
+
+constants  {
+  #C1 = static-tearoff self::_#H#new#tearOff
+  #C2 = static-tearoff self::_#H#named#tearOff
+  #C3 = static-tearoff self::_#H#fact#tearOff
+  #C4 = static-tearoff self::_#H#redirect#tearOff
+  #C5 = static-tearoff mai::_#F#new#tearOff
+  #C6 = static-tearoff mai::_#F#named#tearOff
+  #C7 = static-tearoff mai::_#F#fact#tearOff
+  #C8 = static-tearoff mai::_#F#redirect#tearOff
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_identical.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_identical.dart.weak.modular.expect
new file mode 100644
index 0000000..6da94c4
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_identical.dart.weak.modular.expect
@@ -0,0 +1,148 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "typedef_identical_lib.dart" as typ;
+
+import "org-dartlang-testcase:///typedef_identical_lib.dart";
+
+typedef H<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic> = typ::A<Y%>;
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → typ::A<Y%> H_new = #C1;
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(Y%, [core::int?]) → typ::A<Y%> H_named = #C2;
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(Y%, {b: core::int?, c: core::int}) → typ::A<Y%> H_fact = #C3;
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → typ::A<Y%> H_redirect = #C4;
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → typ::A<Y%> F_new = #C5;
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(Y%, [core::int?]) → typ::A<Y%> F_named = #C6;
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(Y%, {b: core::int?, c: core::int}) → typ::A<Y%> F_fact = #C7;
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → typ::A<Y%> F_redirect = #C8;
+static method main() → dynamic {
+  self::expect(true, core::identical(self::F_new, typ::F_new_lib));
+  self::expect(false, core::identical(self::F_new, typ::F_named_lib));
+  self::expect(false, core::identical(self::F_new, typ::F_fact_lib));
+  self::expect(false, core::identical(self::F_new, typ::F_redirect_lib));
+  self::expect(false, core::identical(self::F_new, typ::G_new_lib));
+  self::expect(false, core::identical(self::F_new, typ::G_named_lib));
+  self::expect(false, core::identical(self::F_new, typ::G_fact_lib));
+  self::expect(false, core::identical(self::F_new, typ::G_redirect_lib));
+  self::expect(false, core::identical(self::F_new, self::H_new));
+  self::expect(false, core::identical(self::F_new, self::H_named));
+  self::expect(false, core::identical(self::F_new, self::H_fact));
+  self::expect(false, core::identical(self::F_new, self::H_redirect));
+  self::expect(false, core::identical(self::F_named, typ::F_new_lib));
+  self::expect(true, core::identical(self::F_named, typ::F_named_lib));
+  self::expect(false, core::identical(self::F_named, typ::F_fact_lib));
+  self::expect(false, core::identical(self::F_named, typ::F_redirect_lib));
+  self::expect(false, core::identical(self::F_named, typ::G_new_lib));
+  self::expect(false, core::identical(self::F_named, typ::G_named_lib));
+  self::expect(false, core::identical(self::F_named, typ::G_fact_lib));
+  self::expect(false, core::identical(self::F_named, typ::G_redirect_lib));
+  self::expect(false, core::identical(self::F_named, self::H_new));
+  self::expect(false, core::identical(self::F_named, self::H_named));
+  self::expect(false, core::identical(self::F_named, self::H_fact));
+  self::expect(false, core::identical(self::F_named, self::H_redirect));
+  self::expect(false, core::identical(self::F_fact, typ::F_new_lib));
+  self::expect(false, core::identical(self::F_fact, typ::F_named_lib));
+  self::expect(true, core::identical(self::F_fact, typ::F_fact_lib));
+  self::expect(false, core::identical(self::F_fact, typ::F_redirect_lib));
+  self::expect(false, core::identical(self::F_fact, typ::G_new_lib));
+  self::expect(false, core::identical(self::F_fact, typ::G_named_lib));
+  self::expect(false, core::identical(self::F_fact, typ::G_fact_lib));
+  self::expect(false, core::identical(self::F_fact, typ::G_redirect_lib));
+  self::expect(false, core::identical(self::F_fact, self::H_new));
+  self::expect(false, core::identical(self::F_fact, self::H_named));
+  self::expect(false, core::identical(self::F_fact, self::H_fact));
+  self::expect(false, core::identical(self::F_fact, self::H_redirect));
+  self::expect(false, core::identical(self::F_redirect, typ::F_new_lib));
+  self::expect(false, core::identical(self::F_redirect, typ::F_named_lib));
+  self::expect(false, core::identical(self::F_redirect, typ::F_fact_lib));
+  self::expect(true, core::identical(self::F_redirect, typ::F_redirect_lib));
+  self::expect(false, core::identical(self::F_redirect, typ::G_new_lib));
+  self::expect(false, core::identical(self::F_redirect, typ::G_named_lib));
+  self::expect(false, core::identical(self::F_redirect, typ::G_fact_lib));
+  self::expect(false, core::identical(self::F_redirect, typ::G_redirect_lib));
+  self::expect(false, core::identical(self::F_redirect, self::H_new));
+  self::expect(false, core::identical(self::F_redirect, self::H_named));
+  self::expect(false, core::identical(self::F_redirect, self::H_fact));
+  self::expect(false, core::identical(self::F_redirect, self::H_redirect));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method /* from org-dartlang-testcase:///typedef_identical_lib.dart */ _#H#new#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → typ::A<self::_#H#new#tearOff::Y%>
+  return new typ::A::•<self::_#H#new#tearOff::Y%>();
+static method /* from org-dartlang-testcase:///typedef_identical_lib.dart */ _#H#named#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(self::_#H#named#tearOff::Y% a, [core::int? b = #C9]) → typ::A<self::_#H#named#tearOff::Y%>
+  return new typ::A::named<self::_#H#named#tearOff::Y%>(a, b);
+static method /* from org-dartlang-testcase:///typedef_identical_lib.dart */ _#H#fact#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(self::_#H#fact#tearOff::Y% a, {core::int? b = #C9, core::int c = #C10}) → typ::A<self::_#H#fact#tearOff::Y%>
+  return typ::A::fact<self::_#H#fact#tearOff::Y%>(a, b: b, c: c);
+static method /* from org-dartlang-testcase:///typedef_identical_lib.dart */ _#H#redirect#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → typ::A<self::_#H#redirect#tearOff::Y%>
+  return typ::A::_#redirect#tearOff<self::_#H#redirect#tearOff::Y%>();
+
+library /*isNonNullableByDefault*/;
+import self as typ;
+import "dart:core" as core;
+
+typedef F<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic> = typ::A<Y%>;
+typedef G<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic> = typ::A<Y%>;
+class A<T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C11]/*isLegacy*/;
+  constructor •() → typ::A<typ::A::T%>
+    : super core::Object::•()
+    ;
+  constructor named(typ::A::T% a, [core::int? b = #C9]) → typ::A<typ::A::T%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → typ::A<typ::A::_#new#tearOff::T%>
+    return new typ::A::•<typ::A::_#new#tearOff::T%>();
+  static method _#named#tearOff<T extends core::Object? = dynamic>(typ::A::_#named#tearOff::T% a, [core::int? b = #C9]) → typ::A<typ::A::_#named#tearOff::T%>
+    return new typ::A::named<typ::A::_#named#tearOff::T%>(a, b);
+  static factory fact<T extends core::Object? = dynamic>(typ::A::fact::T% a, {core::int? b = #C9, core::int c = #C10}) → typ::A<typ::A::fact::T%>
+    return new typ::A::•<typ::A::fact::T%>();
+  static method _#fact#tearOff<T extends core::Object? = dynamic>(typ::A::_#fact#tearOff::T% a, {core::int? b = #C9, core::int c = #C10}) → typ::A<typ::A::_#fact#tearOff::T%>
+    return typ::A::fact<typ::A::_#fact#tearOff::T%>(a, b: b, c: c);
+  static factory redirect<T extends core::Object? = dynamic>() → typ::A<typ::A::redirect::T%>
+    return new typ::A::•<typ::A::redirect::T%>();
+  static method _#redirect#tearOff<T extends core::Object? = dynamic>() → typ::A<typ::A::_#redirect#tearOff::T%>
+    return new typ::A::•<typ::A::_#redirect#tearOff::T%>();
+}
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → typ::A<Y%> F_new_lib = #C5;
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(Y%, [core::int?]) → typ::A<Y%> F_named_lib = #C6;
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(Y%, {b: core::int?, c: core::int}) → typ::A<Y%> F_fact_lib = #C7;
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → typ::A<Y%> F_redirect_lib = #C8;
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → typ::A<Y%> G_new_lib = #C12;
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(Y%, [core::int?]) → typ::A<Y%> G_named_lib = #C13;
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(Y%, {b: core::int?, c: core::int}) → typ::A<Y%> G_fact_lib = #C14;
+static field <unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → typ::A<Y%> G_redirect_lib = #C15;
+static method _#F#new#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → typ::A<typ::_#F#new#tearOff::Y%>
+  return new typ::A::•<typ::_#F#new#tearOff::Y%>();
+static method _#F#named#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(typ::_#F#named#tearOff::Y% a, [core::int? b = #C9]) → typ::A<typ::_#F#named#tearOff::Y%>
+  return new typ::A::named<typ::_#F#named#tearOff::Y%>(a, b);
+static method _#F#fact#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(typ::_#F#fact#tearOff::Y% a, {core::int? b = #C9, core::int c = #C10}) → typ::A<typ::_#F#fact#tearOff::Y%>
+  return typ::A::fact<typ::_#F#fact#tearOff::Y%>(a, b: b, c: c);
+static method _#F#redirect#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → typ::A<typ::_#F#redirect#tearOff::Y%>
+  return typ::A::_#redirect#tearOff<typ::_#F#redirect#tearOff::Y%>();
+static method _#G#new#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → typ::A<typ::_#G#new#tearOff::Y%>
+  return new typ::A::•<typ::_#G#new#tearOff::Y%>();
+static method _#G#named#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(typ::_#G#named#tearOff::Y% a, [core::int? b = #C9]) → typ::A<typ::_#G#named#tearOff::Y%>
+  return new typ::A::named<typ::_#G#named#tearOff::Y%>(a, b);
+static method _#G#fact#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(typ::_#G#fact#tearOff::Y% a, {core::int? b = #C9, core::int c = #C10}) → typ::A<typ::_#G#fact#tearOff::Y%>
+  return typ::A::fact<typ::_#G#fact#tearOff::Y%>(a, b: b, c: c);
+static method _#G#redirect#tearOff<unrelated X extends core::Object? = dynamic, Y extends core::Object? = dynamic>() → typ::A<typ::_#G#redirect#tearOff::Y%>
+  return typ::A::_#redirect#tearOff<typ::_#G#redirect#tearOff::Y%>();
+
+constants  {
+  #C1 = static-tearoff self::_#H#new#tearOff
+  #C2 = static-tearoff self::_#H#named#tearOff
+  #C3 = static-tearoff self::_#H#fact#tearOff
+  #C4 = static-tearoff self::_#H#redirect#tearOff
+  #C5 = static-tearoff typ::_#F#new#tearOff
+  #C6 = static-tearoff typ::_#F#named#tearOff
+  #C7 = static-tearoff typ::_#F#fact#tearOff
+  #C8 = static-tearoff typ::_#F#redirect#tearOff
+  #C9 = null
+  #C10 = 42
+  #C11 = constructor-tearoff typ::A::redirect
+  #C12 = static-tearoff typ::_#G#new#tearOff
+  #C13 = static-tearoff typ::_#G#named#tearOff
+  #C14 = static-tearoff typ::_#G#fact#tearOff
+  #C15 = static-tearoff typ::_#G#redirect#tearOff
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..9e50e01
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart.weak.modular.expect
@@ -0,0 +1,330 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:34:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//     f1a(0); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:46:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//     f2a(0); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:47:8: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'call'.
+// Try changing type arguments so that they conform to the bounds.
+//     f2a<String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:65:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//     f3a(0); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:66:8: Error: Expected 0 type arguments.
+//     f3a<String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:85:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f3c(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:86:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f3c(0, 0); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:87:8: Error: Expected 0 type arguments.
+//     f3c<String>(0); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:107:8: Error: Too few positional arguments: 2 required, 0 given.
+//     f3e(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:108:8: Error: Too few positional arguments: 2 required, 1 given.
+//     f3e(0); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:109:8: Error: Expected 0 type arguments.
+//     f3e<String>(0, ''); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:130:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//     f4a(0); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:131:8: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'call'.
+// Try changing type arguments so that they conform to the bounds.
+//     f4a<String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:152:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//     f5a(0); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:153:8: Error: Expected 2 type arguments.
+//     f5a<String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:154:8: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'call'.
+// Try changing type arguments so that they conform to the bounds.
+//     f5a<String, String>(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:155:8: Error: Type argument 'num' doesn't conform to the bound 'String' of the type variable 'Y' on 'call'.
+// Try changing type arguments so that they conform to the bounds.
+//     f5a<num, num>(); // error
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef DA1 = self::A;
+typedef DA2<unrelated X extends core::num> = self::A;
+typedef DB1 = self::B<core::String>;
+typedef DB2<X extends core::num> = self::B<X>;
+typedef DB3<X extends core::num, unrelated Y extends core::String> = self::B<X>;
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff() → self::A
+    return new self::A::•();
+}
+class B<X extends core::Object? = dynamic> extends core::Object {
+  field core::int field1;
+  field core::String field2;
+  constructor _(core::int field1, core::String field2) → self::B<self::B::X%>
+    : self::B::field1 = field1, self::B::field2 = field2, super core::Object::•()
+    ;
+  constructor •() → self::B<self::B::X%>
+    : this self::B::_(0, "")
+    ;
+  constructor foo(core::int field1) → self::B<self::B::X%>
+    : self::B::field1 = field1, self::B::field2 = "", super core::Object::•()
+    ;
+  static method _#_#tearOff<X extends core::Object? = dynamic>(core::int field1, core::String field2) → self::B<self::B::_#_#tearOff::X%>
+    return new self::B::_<self::B::_#_#tearOff::X%>(field1, field2);
+  static method _#new#tearOff<X extends core::Object? = dynamic>() → self::B<self::B::_#new#tearOff::X%>
+    return new self::B::•<self::B::_#new#tearOff::X%>();
+  static method _#foo#tearOff<X extends core::Object? = dynamic>(core::int field1) → self::B<self::B::_#foo#tearOff::X%>
+    return new self::B::foo<self::B::_#foo#tearOff::X%>(field1);
+  static factory bar<X extends core::Object? = dynamic>(core::int i, core::String j) → self::B<self::B::bar::X%>
+    return new self::B::_<self::B::bar::X%>(i, j);
+  static method _#bar#tearOff<X extends core::Object? = dynamic>(core::int i, core::String j) → self::B<self::B::_#bar#tearOff::X%>
+    return self::B::bar<self::B::_#bar#tearOff::X%>(i, j);
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static method main() → dynamic {
+  () → self::A f1a = #C1;
+  self::A c1a = f1a(){() → self::A};
+  self::expect(true, c1a is{ForNonNullableByDefault} self::A);
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:34:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+    f1a(0); // error
+       ^" in f1a{<inapplicable>}.(0);
+  };
+  dynamic f1b = #C1;
+  dynamic c1b = f1b{dynamic}.call();
+  self::expect(true, c1b is{ForNonNullableByDefault} self::A);
+  self::throws(() → dynamic => f1b{dynamic}.call(0));
+  <unrelated X extends core::num>() → self::A f2a = #C2;
+  self::A c2a = f2a<core::num>(){() → self::A};
+  self::expect(true, c2a is{ForNonNullableByDefault} self::A);
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:46:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+    f2a(0); // error
+       ^" in f2a{<inapplicable>}.<core::num>(0);
+    f2a<core::String>(){() → self::A};
+  };
+  dynamic f2b = #C2;
+  dynamic c2b = f2b{dynamic}.call();
+  self::expect(true, c2b is{ForNonNullableByDefault} self::A);
+  dynamic c2c = f2b{dynamic}.call<core::int>();
+  self::expect(true, c2c is{ForNonNullableByDefault} self::A);
+  self::throws(() → dynamic => f2b{dynamic}.call(0));
+  self::throws(() → dynamic => f2b{dynamic}.call<core::String>());
+  () → self::B<core::String> f3a = #C4;
+  self::B<core::String> c3a = f3a(){() → self::B<core::String>};
+  self::expect(true, c3a is{ForNonNullableByDefault} self::B<core::String>);
+  self::expect(false, c3a is{ForNonNullableByDefault} self::B<core::int>);
+  self::expect(0, c3a.{self::B::field1}{core::int});
+  self::expect("", c3a.{self::B::field2}{core::String});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:65:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+    f3a(0); // error
+       ^" in f3a{<inapplicable>}.(0);
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:66:8: Error: Expected 0 type arguments.
+    f3a<String>(); // error
+       ^" in f3a{<inapplicable>}.<core::String>();
+  };
+  dynamic f3b = #C4;
+  dynamic c3b = f3b{dynamic}.call();
+  self::expect(true, c3b is{ForNonNullableByDefault} self::B<core::String>);
+  self::expect(false, c3b is{ForNonNullableByDefault} self::B<core::int>);
+  self::expect(0, c3a.{self::B::field1}{core::int});
+  self::expect("", c3a.{self::B::field2}{core::String});
+  self::throws(() → dynamic => f3b{dynamic}.call(0));
+  self::throws(() → dynamic => f3b{dynamic}.call<core::String>());
+  (core::int) → self::B<core::String> f3c = #C6;
+  self::B<core::String> c3c = f3c(42){(core::int) → self::B<core::String>};
+  self::expect(true, c3c is{ForNonNullableByDefault} self::B<core::String>);
+  self::expect(false, c3c is{ForNonNullableByDefault} self::B<core::int>);
+  self::expect(42, c3c.{self::B::field1}{core::int});
+  self::expect("", c3c.{self::B::field2}{core::String});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:85:8: Error: Too few positional arguments: 1 required, 0 given.
+    f3c(); // error
+       ^" in f3c{<inapplicable>}.();
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:86:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f3c(0, 0); // error
+       ^" in f3c{<inapplicable>}.(0, 0);
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:87:8: Error: Expected 0 type arguments.
+    f3c<String>(0); // error
+       ^" in f3c{<inapplicable>}.<core::String>(0);
+  };
+  dynamic f3d = #C6;
+  dynamic c3d = f3d{dynamic}.call(42);
+  self::expect(true, c3d is{ForNonNullableByDefault} self::B<core::String>);
+  self::expect(false, c3d is{ForNonNullableByDefault} self::B<core::int>);
+  self::expect(42, c3d{dynamic}.field1);
+  self::expect("", c3d{dynamic}.field2);
+  self::throws(() → dynamic => f3d{dynamic}.call());
+  self::throws(() → dynamic => f3d{dynamic}.call(0, 0));
+  self::throws(() → dynamic => f3d{dynamic}.call<core::String>(0));
+  (core::int, core::String) → self::B<core::String> f3e = #C8;
+  self::B<core::String> c3e = f3e(42, "foo"){(core::int, core::String) → self::B<core::String>};
+  self::expect(true, c3e is{ForNonNullableByDefault} self::B<core::String>);
+  self::expect(false, c3e is{ForNonNullableByDefault} self::B<core::int>);
+  self::expect(42, c3e.{self::B::field1}{core::int});
+  self::expect("foo", c3e.{self::B::field2}{core::String});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:107:8: Error: Too few positional arguments: 2 required, 0 given.
+    f3e(); // error
+       ^" in f3e{<inapplicable>}.();
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:108:8: Error: Too few positional arguments: 2 required, 1 given.
+    f3e(0); // error
+       ^" in f3e{<inapplicable>}.(0);
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:109:8: Error: Expected 0 type arguments.
+    f3e<String>(0, ''); // error
+       ^" in f3e{<inapplicable>}.<core::String>(0, "");
+  };
+  dynamic f3f = #C8;
+  dynamic c3f = f3f{dynamic}.call(42, "foo");
+  self::expect(true, c3f is{ForNonNullableByDefault} self::B<core::String>);
+  self::expect(false, c3f is{ForNonNullableByDefault} self::B<core::int>);
+  self::expect(42, c3f{dynamic}.field1);
+  self::expect("foo", c3f{dynamic}.field2);
+  self::throws(() → dynamic => c3f{dynamic}.call());
+  self::throws(() → dynamic => c3f{dynamic}.call(0));
+  self::throws(() → dynamic => c3f{dynamic}.call<core::String>(0));
+  <X extends core::num>() → self::B<X> f4a = #C9;
+  self::B<core::num> c4a = f4a<core::num>(){() → self::B<core::num>};
+  self::expect(true, c4a is{ForNonNullableByDefault} self::B<core::num>);
+  self::expect(false, c4a is{ForNonNullableByDefault} self::B<core::int>);
+  self::B<core::int> c4b = f4a<core::int>(){() → self::B<core::int>};
+  self::expect(true, c4b is{ForNonNullableByDefault} self::B<core::int>);
+  self::expect(false, c4b is{ForNonNullableByDefault} self::B<core::double>);
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:130:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+    f4a(0); // error
+       ^" in f4a{<inapplicable>}.<core::num>(0);
+    f4a<core::String>(){() → self::B<core::String>};
+  };
+  dynamic f4b = #C9;
+  dynamic c4c = f4b{dynamic}.call();
+  self::expect(true, c4c is{ForNonNullableByDefault} self::B<core::num>);
+  self::expect(false, c4c is{ForNonNullableByDefault} self::B<core::int>);
+  dynamic c4d = f4b{dynamic}.call<core::int>();
+  self::expect(true, c4d is{ForNonNullableByDefault} self::B<core::int>);
+  self::expect(false, c4d is{ForNonNullableByDefault} self::B<core::double>);
+  self::throws(() → dynamic => f4b{dynamic}.call(0));
+  self::throws(() → dynamic => f4b{dynamic}.call<core::String>());
+  <X extends core::num, unrelated Y extends core::String>() → self::B<X> f5a = #C10;
+  self::B<core::num> c5a = f5a<core::num, core::String>(){() → self::B<core::num>};
+  self::expect(true, c5a is{ForNonNullableByDefault} self::B<core::num>);
+  self::expect(false, c5a is{ForNonNullableByDefault} self::B<core::int>);
+  self::B<core::int> c5b = f5a<core::int, core::String>(){() → self::B<core::int>};
+  self::expect(true, c5b is{ForNonNullableByDefault} self::B<core::int>);
+  self::expect(false, c5b is{ForNonNullableByDefault} self::B<core::double>);
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:152:8: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+    f5a(0); // error
+       ^" in f5a{<inapplicable>}.<core::num, core::String>(0);
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/lowering/typedef_tear_off.dart:153:8: Error: Expected 2 type arguments.
+    f5a<String>(); // error
+       ^" in f5a{<inapplicable>}.<core::String>();
+    f5a<core::String, core::String>(){() → self::B<core::String>};
+    f5a<core::num, core::num>(){() → self::B<core::num>};
+  };
+  dynamic f5b = #C10;
+  dynamic c5c = f5b{dynamic}.call();
+  self::expect(true, c5c is{ForNonNullableByDefault} self::B<core::num>);
+  self::expect(false, c5c is{ForNonNullableByDefault} self::B<core::int>);
+  dynamic c5d = f5b{dynamic}.call<core::int, core::String>();
+  self::expect(true, c5d is{ForNonNullableByDefault} self::B<core::int>);
+  self::expect(false, c5d is{ForNonNullableByDefault} self::B<core::double>);
+  self::throws(() → dynamic => f5b{dynamic}.call(0));
+  self::throws(() → dynamic => f5b{dynamic}.call<core::String>());
+  self::throws(() → dynamic => f5b{dynamic}.call<core::String, core::String>());
+  self::throws(() → dynamic => f5b{dynamic}.call<core::num, core::num>());
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, {core::bool inSoundModeOnly = #C11}) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print("Thrown: ${e}");
+    return;
+  }
+  if(!self::inSoundMode && inSoundModeOnly) {
+    return;
+  }
+  throw "Expected exception";
+}
+static method _#DA2#new#tearOff<unrelated X extends core::num>() → self::A
+  return new self::A::•();
+static method _#DB2#_#tearOff<X extends core::num>(core::int field1, core::String field2) → self::B<self::_#DB2#_#tearOff::X>
+  return new self::B::_<self::_#DB2#_#tearOff::X>(field1, field2);
+static method _#DB2#new#tearOff<X extends core::num>() → self::B<self::_#DB2#new#tearOff::X>
+  return new self::B::•<self::_#DB2#new#tearOff::X>();
+static method _#DB2#foo#tearOff<X extends core::num>(core::int field1) → self::B<self::_#DB2#foo#tearOff::X>
+  return new self::B::foo<self::_#DB2#foo#tearOff::X>(field1);
+static method _#DB2#bar#tearOff<X extends core::num>(core::int i, core::String j) → self::B<self::_#DB2#bar#tearOff::X>
+  return self::B::bar<self::_#DB2#bar#tearOff::X>(i, j);
+static method _#DB3#_#tearOff<X extends core::num, unrelated Y extends core::String>(core::int field1, core::String field2) → self::B<self::_#DB3#_#tearOff::X>
+  return new self::B::_<self::_#DB3#_#tearOff::X>(field1, field2);
+static method _#DB3#new#tearOff<X extends core::num, unrelated Y extends core::String>() → self::B<self::_#DB3#new#tearOff::X>
+  return new self::B::•<self::_#DB3#new#tearOff::X>();
+static method _#DB3#foo#tearOff<X extends core::num, unrelated Y extends core::String>(core::int field1) → self::B<self::_#DB3#foo#tearOff::X>
+  return new self::B::foo<self::_#DB3#foo#tearOff::X>(field1);
+static method _#DB3#bar#tearOff<X extends core::num, unrelated Y extends core::String>(core::int i, core::String j) → self::B<self::_#DB3#bar#tearOff::X>
+  return self::B::bar<self::_#DB3#bar#tearOff::X>(i, j);
+
+constants  {
+  #C1 = static-tearoff self::A::_#new#tearOff
+  #C2 = static-tearoff self::_#DA2#new#tearOff
+  #C3 = static-tearoff self::B::_#new#tearOff
+  #C4 = instantiation #C3 <core::String*>
+  #C5 = static-tearoff self::B::_#foo#tearOff
+  #C6 = instantiation #C5 <core::String*>
+  #C7 = static-tearoff self::B::_#bar#tearOff
+  #C8 = instantiation #C7 <core::String*>
+  #C9 = static-tearoff self::_#DB2#new#tearOff
+  #C10 = static-tearoff self::_#DB3#new#tearOff
+  #C11 = false
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart.weak.modular.expect
new file mode 100644
index 0000000..911cbda
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart.weak.modular.expect
@@ -0,0 +1,130 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart:26:25: Error: Member not found: 'fact'.
+//   NamedMixinApplication.fact;
+//                         ^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart:27:25: Error: Member not found: 'redirectingFactory'.
+//   NamedMixinApplication.redirectingFactory;
+//                         ^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart:29:33: Error: Constructors on abstract classes can't be torn off.
+//   AbstractNamedMixinApplication.new;
+//                                 ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart:30:33: Error: Constructors on abstract classes can't be torn off.
+//   AbstractNamedMixinApplication.named;
+//                                 ^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart:31:33: Error: Constructors on abstract classes can't be torn off.
+//   AbstractNamedMixinApplication.redirectingGenerative;
+//                                 ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart:32:33: Error: Member not found: 'fact'.
+//   AbstractNamedMixinApplication.fact;
+//                                 ^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart:33:33: Error: Member not found: 'redirectingFactory'.
+//   AbstractNamedMixinApplication.redirectingFactory;
+//                                 ^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  abstract get field() → core::int;
+}
+class Class<T extends core::Object? = dynamic> extends core::Object implements self::Interface {
+  field core::int field;
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor •([core::int field = #C2]) → self::Class<self::Class::T%>
+    : self::Class::field = field, super core::Object::•()
+    ;
+  constructor named(core::int field) → self::Class<self::Class::T%>
+    : self::Class::field = field, super core::Object::•()
+    ;
+  constructor redirectingGenerative(core::int field) → self::Class<self::Class::T%>
+    : this self::Class::•(field)
+    ;
+  static factory fact<T extends core::Object? = dynamic>(core::int field) → self::Class<self::Class::fact::T%>
+    return new self::Class::•<self::Class::fact::T%>(field);
+  static factory redirectingFactory<T extends core::Object? = dynamic>(core::int field) → self::Class<self::Class::redirectingFactory::T%>
+    return new self::Class::•<self::Class::redirectingFactory::T%>(field);
+}
+abstract class Mixin<S extends core::Object? = dynamic> extends core::Object /*isMixinDeclaration*/  {
+}
+class NamedMixinApplication<T extends core::Object? = dynamic, S extends core::Object? = dynamic> = self::Class<self::NamedMixinApplication::T%> with self::Mixin<self::NamedMixinApplication::S%> {
+  synthetic constructor •([core::int field = #C2]) → self::NamedMixinApplication<self::NamedMixinApplication::T%, self::NamedMixinApplication::S%>
+    : super self::Class::•(field)
+    ;
+  synthetic constructor named(core::int field) → self::NamedMixinApplication<self::NamedMixinApplication::T%, self::NamedMixinApplication::S%>
+    : super self::Class::named(field)
+    ;
+  synthetic constructor redirectingGenerative(core::int field) → self::NamedMixinApplication<self::NamedMixinApplication::T%, self::NamedMixinApplication::S%>
+    : super self::Class::redirectingGenerative(field)
+    ;
+}
+abstract class AbstractNamedMixinApplication<T extends core::Object? = dynamic, S extends core::Object? = dynamic> = self::Class<self::AbstractNamedMixinApplication::T%> with self::Mixin<self::AbstractNamedMixinApplication::S%> {
+  synthetic constructor •([core::int field = #C2]) → self::AbstractNamedMixinApplication<self::AbstractNamedMixinApplication::T%, self::AbstractNamedMixinApplication::S%>
+    : super self::Class::•(field)
+    ;
+  synthetic constructor named(core::int field) → self::AbstractNamedMixinApplication<self::AbstractNamedMixinApplication::T%, self::AbstractNamedMixinApplication::S%>
+    : super self::Class::named(field)
+    ;
+  synthetic constructor redirectingGenerative(core::int field) → self::AbstractNamedMixinApplication<self::AbstractNamedMixinApplication::T%, self::AbstractNamedMixinApplication::S%>
+    : super self::Class::redirectingGenerative(field)
+    ;
+}
+static field <T extends core::Object? = dynamic, S extends core::Object? = dynamic>([core::int]) → self::NamedMixinApplication<T%, S%> f1 = #C3;
+static field <T extends core::Object? = dynamic, S extends core::Object? = dynamic>(core::int) → self::NamedMixinApplication<T%, S%> f2 = #C4;
+static field <T extends core::Object? = dynamic, S extends core::Object? = dynamic>(core::int) → self::NamedMixinApplication<T%, S%> f3 = #C5;
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart:26:25: Error: Member not found: 'fact'.
+  NamedMixinApplication.fact;
+                        ^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart:27:25: Error: Member not found: 'redirectingFactory'.
+  NamedMixinApplication.redirectingFactory;
+                        ^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart:29:33: Error: Constructors on abstract classes can't be torn off.
+  AbstractNamedMixinApplication.new;
+                                ^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart:30:33: Error: Constructors on abstract classes can't be torn off.
+  AbstractNamedMixinApplication.named;
+                                ^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart:31:33: Error: Constructors on abstract classes can't be torn off.
+  AbstractNamedMixinApplication.redirectingGenerative;
+                                ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart:32:33: Error: Member not found: 'fact'.
+  AbstractNamedMixinApplication.fact;
+                                ^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart:33:33: Error: Member not found: 'redirectingFactory'.
+  AbstractNamedMixinApplication.redirectingFactory;
+                                ^^^^^^^^^^^^^^^^^^";
+}
+static method main() → dynamic {
+  <T extends core::Object? = dynamic, S extends core::Object? = dynamic>([core::int]) → self::NamedMixinApplication<T%, S%> f1 = #C3;
+  <T extends core::Object? = dynamic, S extends core::Object? = dynamic>(core::int) → self::NamedMixinApplication<T%, S%> f2 = #C4;
+  <T extends core::Object? = dynamic, S extends core::Object? = dynamic>(core::int) → self::NamedMixinApplication<T%, S%> f3 = #C5;
+  #C6;
+  #C7;
+  #C8;
+  ([core::int]) → self::NamedMixinApplication<core::int, core::String> n1 = f1<core::int, core::String>;
+  (core::int) → self::NamedMixinApplication<core::int, core::String> n2 = f2<core::int, core::String>;
+  (core::int) → self::NamedMixinApplication<core::int, core::String> n3 = f3<core::int, core::String>;
+}
+
+constants  {
+  #C1 = constructor-tearoff self::Class::redirectingFactory
+  #C2 = 0
+  #C3 = constructor-tearoff self::NamedMixinApplication::•
+  #C4 = constructor-tearoff self::NamedMixinApplication::named
+  #C5 = constructor-tearoff self::NamedMixinApplication::redirectingGenerative
+  #C6 = instantiation #C3 <core::int*, core::String*>
+  #C7 = instantiation #C4 <core::int*, core::String*>
+  #C8 = instantiation #C5 <core::int*, core::String*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart.weak.outline.expect b/pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart.weak.outline.expect
index 99e5f30..c282d10 100644
--- a/pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/constructor_tearoffs/named_mixin_application.dart.weak.outline.expect
@@ -10,7 +10,7 @@
 class Class<T extends core::Object? = dynamic> extends core::Object implements self::Interface {
   field core::int field;
   static final field dynamic _redirecting# = <dynamic>[self::Class::redirectingFactory]/*isLegacy*/;
-  constructor •([core::int field]) → self::Class<self::Class::T%>
+  constructor •([core::int field = 0]) → self::Class<self::Class::T%>
     ;
   constructor named(core::int field) → self::Class<self::Class::T%>
     ;
diff --git a/pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart.weak.modular.expect
new file mode 100644
index 0000000..75ac16e
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart.weak.modular.expect
@@ -0,0 +1,261 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:8:5: Error: 'new' can't be used as an identifier because it's a keyword.
+// Try renaming this to be an identifier that isn't a keyword.
+// int new = 87; // error
+//     ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:15:7: Error: 'new' can't be used as an identifier because it's a keyword.
+// Try renaming this to be an identifier that isn't a keyword.
+//   int new = 42; // error
+//       ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:29:16: Error: 'new' can't be used as an identifier because it's a keyword.
+// Try renaming this to be an identifier that isn't a keyword.
+//   external int new; // error
+//                ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:21:10: Error: 'new' can only be used as a constructor reference.
+//     this.new; // error
+//          ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:22:10: Error: 'new' can only be used as a constructor reference.
+//     this.new(); // error
+//          ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:23:10: Error: 'new' can only be used as a constructor reference.
+//     this.new<int>(); // error
+//          ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:24:10: Error: 'new' can only be used as a constructor reference.
+//     this.new = 87; // error
+//          ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:34:24: Error: 'new' can only be used as a constructor reference.
+// method(dynamic d) => d.new; // error
+//                        ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:37:11: Error: 'new' can only be used as a constructor reference.
+//   new C().new; // error
+//           ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:38:11: Error: 'new' can only be used as a constructor reference.
+//   new C().new(); // error
+//           ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:39:11: Error: 'new' can only be used as a constructor reference.
+//   new C().new = 87; // error
+//           ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:41:5: Error: 'new' can only be used as a constructor reference.
+//   c.new; // error
+//     ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:42:5: Error: 'new' can only be used as a constructor reference.
+//   c.new = 87; // error
+//     ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:44:7: Error: 'new' can only be used as a constructor reference.
+//   foo.new; // error
+//       ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:45:7: Error: 'new' can only be used as a constructor reference.
+//   foo.new(); // error
+//       ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:46:7: Error: 'new' can only be used as a constructor reference.
+//   foo.new<int>(); // error
+//       ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:47:8: Error: 'new' can only be used as a constructor reference.
+//   foo?.new; // error
+//        ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:48:8: Error: 'new' can only be used as a constructor reference.
+//   foo?.new(); // error
+//        ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:49:8: Error: 'new' can only be used as a constructor reference.
+//   foo?.new<int>(); // error
+//        ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:50:8: Error: 'new' can only be used as a constructor reference.
+//   foo..new; // error
+//        ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:51:8: Error: 'new' can only be used as a constructor reference.
+//   foo..new(); // error
+//        ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:52:8: Error: 'new' can only be used as a constructor reference.
+//   foo..new<int>(); // error
+//        ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:53:9: Error: 'new' can only be used as a constructor reference.
+//   (foo).new; // error
+//         ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:54:9: Error: 'new' can only be used as a constructor reference.
+//   (foo).new(); // error
+//         ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:55:9: Error: 'new' can only be used as a constructor reference.
+//   (foo).new<int>(); // error
+//         ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:56:11: Error: 'new' can only be used as a constructor reference.
+//   prefix1.new; // error
+//           ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:57:11: Error: 'new' can only be used as a constructor reference.
+//   prefix1.new(); // error
+//           ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:58:11: Error: 'new' can only be used as a constructor reference.
+//   prefix1.new<int>(); // error
+//           ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:59:13: Error: 'new' can only be used as a constructor reference.
+//   prefix2.c.new; // error
+//             ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:60:13: Error: 'new' can only be used as a constructor reference.
+//   prefix2.c.new(); // error
+//             ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:61:13: Error: 'new' can only be used as a constructor reference.
+//   prefix2.c.new<int>(); // error
+//             ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:62:8: Error: 'new' can only be used as a constructor reference.
+//   E(0).new; // error
+//        ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:63:8: Error: 'new' can only be used as a constructor reference.
+//   E(0).new(); // error
+//        ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:64:8: Error: 'new' can only be used as a constructor reference.
+//   E(0).new<int>(); // error
+//        ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:65:3: Error: Undefined name 'unresolved'.
+//   unresolved.new; // error
+//   ^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:65:14: Error: 'new' can only be used as a constructor reference.
+//   unresolved.new; // error
+//              ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:66:3: Error: Undefined name 'unresolved'.
+//   unresolved.new(); // error
+//   ^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:66:14: Error: 'new' can only be used as a constructor reference.
+//   unresolved.new(); // error
+//              ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:67:3: Error: Undefined name 'unresolved'.
+//   unresolved.new<int>(); // error
+//   ^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:67:14: Error: 'new' can only be used as a constructor reference.
+//   unresolved.new<int>(); // error
+//              ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///new_as_selector.dart" as prefix1;
+import "org-dartlang-testcase:///new_as_selector.dart" deferred as prefix2 hide E;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+}
+class C extends self::Super {
+  field core::int new = 42;
+  constructor •() → self::C
+    : super self::Super::•()
+    ;
+  constructor named() → self::C
+    : this self::C::•()
+    ;
+  method method() → dynamic {
+    this.{self::C::new}{core::int};
+    self::E|call<dynamic>(this.{self::C::new}{core::int});
+    self::E|call<core::int>(this.{self::C::new}{core::int});
+    this.{self::C::new} = 87;
+  }
+}
+extension E on core::int {
+  get new = self::E|get#new;
+  set new = self::E|set#new;
+  method call = self::E|call;
+  tearoff call = self::E|get#call;
+}
+static field core::int new = 87;
+static field self::C c = new self::C::•();
+external static method E|get#new(core::int #this) → core::int;
+external static method E|set#new(core::int #this, core::int #externalFieldValue) → void;
+static method E|call<T extends core::Object? = dynamic>(lowered final core::int #this) → dynamic {}
+static method E|get#call(lowered final core::int #this) → <T extends core::Object? = dynamic>() → dynamic
+  return <T extends core::Object? = dynamic>() → dynamic => self::E|call<T%>(#this);
+static method method(dynamic d) → dynamic
+  return d{dynamic}.new;
+static method test() → dynamic {
+  new self::C::•().{self::C::new}{core::int};
+  self::E|call<dynamic>(new self::C::•().{self::C::new}{core::int});
+  new self::C::•().{self::C::new} = 87;
+  self::C c = new self::C::•();
+  c.{self::C::new}{core::int};
+  c.{self::C::new} = 87;
+  dynamic foo;
+  foo{dynamic}.new;
+  foo{dynamic}.new();
+  foo{dynamic}.new<core::int>();
+  let final dynamic #t1 = foo in #t1 == null ?{dynamic} null : #t1{dynamic}.new;
+  let final dynamic #t2 = foo in #t2 == null ?{dynamic} null : #t2{dynamic}.new();
+  let final dynamic #t3 = foo in #t3 == null ?{dynamic} null : #t3{dynamic}.new<core::int>();
+  let final dynamic #t4 = foo in block {
+    #t4{dynamic}.new;
+  } =>#t4;
+  let final dynamic #t5 = foo in block {
+    #t5{dynamic}.new();
+  } =>#t5;
+  let final dynamic #t6 = foo in block {
+    #t6{dynamic}.new<core::int>();
+  } =>#t6;
+  foo{dynamic}.new;
+  foo{dynamic}.new();
+  foo{dynamic}.new<core::int>();
+  self::new;
+  self::E|call<dynamic>(self::new);
+  self::E|call<core::int>(self::new);
+  let final dynamic #t7 = CheckLibraryIsLoaded(prefix2) in self::c.{self::C::new}{core::int};
+  let final dynamic #t8 = CheckLibraryIsLoaded(prefix2) in self::E|call<dynamic>(self::c.{self::C::new}{core::int});
+  let final dynamic #t9 = CheckLibraryIsLoaded(prefix2) in self::E|call<core::int>(self::c.{self::C::new}{core::int});
+  self::E|get#new(0);
+  self::E|call<dynamic>(self::E|get#new(0));
+  self::E|call<core::int>(self::E|get#new(0));
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:65:3: Error: Undefined name 'unresolved'.
+  unresolved.new; // error
+  ^^^^^^^^^^"{<invalid>}.new;
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:66:3: Error: Undefined name 'unresolved'.
+  unresolved.new(); // error
+  ^^^^^^^^^^"{dynamic}.new();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/new_as_selector.dart:67:3: Error: Undefined name 'unresolved'.
+  unresolved.new<int>(); // error
+  ^^^^^^^^^^"{dynamic}.new<core::int>();
+}
+static method main() → dynamic {
+  #C1;
+  new self::C::•();
+}
+
+constants  {
+  #C1 = constructor-tearoff self::C::•
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_with_context.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_with_context.dart.weak.modular.expect
new file mode 100644
index 0000000..9f6be91
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_with_context.dart.weak.modular.expect
@@ -0,0 +1,61 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_with_context.dart:13:25: Error: A value of type 'A Function(int)' can't be returned from a function with return type 'A Function()'.
+//  - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_with_context.dart'.
+// A Function() test2() => A.foo2; // Error.
+//                         ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_with_context.dart:15:28: Error: A value of type 'A Function()' can't be returned from a function with return type 'A Function(int)'.
+//  - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_with_context.dart'.
+// A Function(int) test4() => A.new; // Error.
+//                            ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_with_context.dart:17:28: Error: A value of type 'A Function()' can't be returned from a function with return type 'A Function(int)'.
+//  - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_with_context.dart'.
+// A Function(int) test6() => A.bar1; // Error.
+//                            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  constructor foo1() → self::A
+    : super core::Object::•() {}
+  constructor foo2(core::int x) → self::A
+    : super core::Object::•() {}
+  constructor •() → self::A
+    : super core::Object::•() {}
+  static factory bar1() → self::A
+    return new self::A::•();
+}
+static method test1() → () → self::A
+  return #C1;
+static method test2() → () → self::A
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_with_context.dart:13:25: Error: A value of type 'A Function(int)' can't be returned from a function with return type 'A Function()'.
+ - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_with_context.dart'.
+A Function() test2() => A.foo2; // Error.
+                        ^" in #C2 as{TypeError,ForNonNullableByDefault} () → self::A;
+static method test3() → () → self::A
+  return #C3;
+static method test4() → (core::int) → self::A
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_with_context.dart:15:28: Error: A value of type 'A Function()' can't be returned from a function with return type 'A Function(int)'.
+ - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_with_context.dart'.
+A Function(int) test4() => A.new; // Error.
+                           ^" in #C3 as{TypeError,ForNonNullableByDefault} (core::int) → self::A;
+static method test5() → () → self::A
+  return #C4;
+static method test6() → (core::int) → self::A
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_with_context.dart:17:28: Error: A value of type 'A Function()' can't be returned from a function with return type 'A Function(int)'.
+ - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_with_context.dart'.
+A Function(int) test6() => A.bar1; // Error.
+                           ^" in #C4 as{TypeError,ForNonNullableByDefault} (core::int) → self::A;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::A::foo1
+  #C2 = constructor-tearoff self::A::foo2
+  #C3 = constructor-tearoff self::A::•
+  #C4 = constructor-tearoff self::A::bar1
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_without_context.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_without_context.dart.weak.modular.expect
new file mode 100644
index 0000000..22aef61
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_without_context.dart.weak.modular.expect
@@ -0,0 +1,64 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_without_context.dart:15:23: Error: The static type of the explicit instantiation operand must be a generic function type but is 'A Function()'.
+//  - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_without_context.dart'.
+// Try changing the operand or remove the type arguments.
+// testFooExtraArgs() => A<int>.foo; // Error.
+//                       ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_without_context.dart:16:23: Error: The static type of the explicit instantiation operand must be a generic function type but is 'A Function()'.
+//  - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_without_context.dart'.
+// Try changing the operand or remove the type arguments.
+// testNewExtraArgs() => A<int>.new; // Error.
+//                       ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_without_context.dart:17:23: Error: The static type of the explicit instantiation operand must be a generic function type but is 'A Function()'.
+//  - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_without_context.dart'.
+// Try changing the operand or remove the type arguments.
+// testBarExtraArgs() => A<int>.bar; // Error.
+//                       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  constructor foo() → self::A
+    : super core::Object::•() {}
+  constructor •() → self::A
+    : super core::Object::•() {}
+  static factory bar() → self::A
+    return new self::A::•();
+}
+static method testFoo() → dynamic
+  return #C1;
+static method testNew() → dynamic
+  return #C2;
+static method testBar() → dynamic
+  return #C3;
+static method testFooExtraArgs() → dynamic
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_without_context.dart:15:23: Error: The static type of the explicit instantiation operand must be a generic function type but is 'A Function()'.
+ - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_without_context.dart'.
+Try changing the operand or remove the type arguments.
+testFooExtraArgs() => A<int>.foo; // Error.
+                      ^";
+static method testNewExtraArgs() → dynamic
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_without_context.dart:16:23: Error: The static type of the explicit instantiation operand must be a generic function type but is 'A Function()'.
+ - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_without_context.dart'.
+Try changing the operand or remove the type arguments.
+testNewExtraArgs() => A<int>.new; // Error.
+                      ^";
+static method testBarExtraArgs() → dynamic
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_without_context.dart:17:23: Error: The static type of the explicit instantiation operand must be a generic function type but is 'A Function()'.
+ - 'A' is from 'pkg/front_end/testcases/constructor_tearoffs/nongeneric_tearoff_without_context.dart'.
+Try changing the operand or remove the type arguments.
+testBarExtraArgs() => A<int>.bar; // Error.
+                      ^";
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::A::foo
+  #C2 = constructor-tearoff self::A::•
+  #C3 = constructor-tearoff self::A::bar
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/not_unresolved_constructor_invocation.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/not_unresolved_constructor_invocation.dart.weak.modular.expect
new file mode 100644
index 0000000..b3fb9eb
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/not_unresolved_constructor_invocation.dart.weak.modular.expect
@@ -0,0 +1,66 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class ResolvedClass<T extends core::Object? = dynamic> extends core::Object {
+  constructor named() → self::ResolvedClass<self::ResolvedClass::T%>
+    : super core::Object::•()
+    ;
+  static method unresolvedConstructor() → dynamic {}
+}
+class unresolved_prefix extends core::Object {
+  synthetic constructor •() → self::unresolved_prefix
+    : super core::Object::•()
+    ;
+  static method UnresolvedClass<T extends core::Object? = dynamic>() → dynamic {}
+}
+class resolved_prefix extends core::Object {
+  synthetic constructor •() → self::resolved_prefix
+    : super core::Object::•()
+    ;
+  static method UnresolvedClass<T extends core::Object? = dynamic>() → dynamic {}
+}
+extension Extension on core::Function {
+  method unresolvedConstructor = self::Extension|unresolvedConstructor;
+  tearoff unresolvedConstructor = self::Extension|get#unresolvedConstructor;
+}
+static method UnresolvedClass<T extends core::Object? = dynamic>() → dynamic {}
+static method Extension|unresolvedConstructor(lowered final core::Function #this) → dynamic {}
+static method Extension|get#unresolvedConstructor(lowered final core::Function #this) → () → dynamic
+  return () → dynamic => self::Extension|unresolvedConstructor(#this);
+static method main() → dynamic {
+  self::UnresolvedClass<dynamic>();
+  self::Extension|unresolvedConstructor(#C1);
+  self::Extension|unresolvedConstructor(#C1);
+  self::unresolved_prefix::UnresolvedClass<dynamic>();
+  self::unresolved_prefix::UnresolvedClass<dynamic>();
+  self::Extension|unresolvedConstructor(#C2);
+  self::Extension|unresolvedConstructor(#C2);
+  self::UnresolvedClass<core::int>();
+  self::UnresolvedClass<core::int>();
+  self::Extension|unresolvedConstructor(#C3);
+  self::Extension|unresolvedConstructor(#C3);
+  self::unresolved_prefix::UnresolvedClass<core::int>();
+  self::unresolved_prefix::UnresolvedClass<core::int>();
+  self::Extension|unresolvedConstructor(#C4);
+  self::Extension|unresolvedConstructor(#C4);
+  self::ResolvedClass::unresolvedConstructor();
+  self::ResolvedClass::unresolvedConstructor();
+  self::resolved_prefix::UnresolvedClass<dynamic>();
+  self::resolved_prefix::UnresolvedClass<dynamic>();
+  self::Extension|unresolvedConstructor(#C5);
+  self::Extension|unresolvedConstructor(#C5);
+  self::resolved_prefix::UnresolvedClass<core::int>();
+  self::resolved_prefix::UnresolvedClass<core::int>();
+  self::Extension|unresolvedConstructor(#C6);
+  self::Extension|unresolvedConstructor(#C6);
+}
+
+constants  {
+  #C1 = static-tearoff self::UnresolvedClass
+  #C2 = static-tearoff self::unresolved_prefix::UnresolvedClass
+  #C3 = instantiation #C1 <core::int*>
+  #C4 = instantiation #C2 <core::int*>
+  #C5 = static-tearoff self::resolved_prefix::UnresolvedClass
+  #C6 = instantiation #C5 <core::int*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/redirecting_constructors.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/redirecting_constructors.dart.weak.modular.expect
new file mode 100644
index 0000000..4e40f0b
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/redirecting_constructors.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/redirecting_constructors.dart:20:5: Error: Expected ';' after this.
+//   A x3 f3();
+//     ^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1, #C2, #C3]/*isLegacy*/;
+  constructor •() → self::A
+    : super core::Object::•()
+    ;
+  static factory redirectingFactory() → self::A
+    return new self::A::•();
+  static factory redirectingFactoryChild() → self::A
+    return new self::B::•();
+  static factory redirectingTwice() → self::A
+    return self::A::redirectingFactory();
+}
+class B extends self::A {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+}
+static method test() → dynamic {
+  () → self::A f1 = #C4;
+  () → self::A f2 = #C5;
+  () → self::A f3 = #C6;
+  self::A x1 = f1(){() → self::A};
+  self::B x2 = f2(){() → self::A} as{ForNonNullableByDefault} self::B;
+  self::A x3;
+  f3(){() → self::A};
+}
+static method main() → dynamic
+  return self::test();
+
+constants  {
+  #C1 = constructor-tearoff self::A::redirectingFactory
+  #C2 = constructor-tearoff self::A::redirectingFactoryChild
+  #C3 = constructor-tearoff self::A::redirectingTwice
+  #C4 = redirecting-factory-tearoff self::A::redirectingFactory
+  #C5 = redirecting-factory-tearoff self::A::redirectingFactoryChild
+  #C6 = redirecting-factory-tearoff self::A::redirectingTwice
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..05e5e9d
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart.weak.modular.expect
@@ -0,0 +1,280 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:99:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f3a(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:100:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f3a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:115:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f4a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:129:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f5a(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:130:8: Error: Too many positional arguments: 2 allowed, but 3 found.
+// Try removing the extra positional arguments.
+//     f5a(42, 87, 123); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:142:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f6a(); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:143:8: Error: Required named parameter 'field3' must be provided.
+//     f6a(42); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:144:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     f6a(42, 87); // error
+//        ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:145:8: Error: Too few positional arguments: 1 required, 0 given.
+//     f6a(field1: 87, field2: 87); // error
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor _() → self::Class1
+    : super core::Object::•()
+    ;
+  static factory •() → self::Class1
+    return new self::Class1::_();
+}
+class Class2 extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C2]/*isLegacy*/;
+  constructor __() → self::Class2
+    : super core::Object::•()
+    ;
+  static factory _() → self::Class2
+    return new self::Class2::__();
+  static factory named() → self::Class2
+    return self::Class2::_();
+}
+class Class3 extends core::Object {
+  final field core::int field;
+  static final field dynamic _redirecting# = <dynamic>[#C3]/*isLegacy*/;
+  constructor _(core::int field) → self::Class3
+    : self::Class3::field = field, super core::Object::•()
+    ;
+  static factory •(core::int field) → self::Class3
+    return new self::Class3::_(field);
+}
+class Class4 extends core::Object {
+  final field core::int? field;
+  static final field dynamic _redirecting# = <dynamic>[#C4]/*isLegacy*/;
+  constructor _([core::int? field = #C5]) → self::Class4
+    : self::Class4::field = field, super core::Object::•()
+    ;
+  static factory •([core::int? field = #C5]) → self::Class4
+    return new self::Class4::_(field);
+}
+class Class5 extends core::Object {
+  final field core::int field1;
+  final field core::int? field2;
+  static final field dynamic _redirecting# = <dynamic>[#C6]/*isLegacy*/;
+  constructor _(core::int field1, [core::int? field2 = #C5]) → self::Class5
+    : self::Class5::field1 = field1, self::Class5::field2 = field2, super core::Object::•()
+    ;
+  static factory •(core::int field1, [core::int? field2 = #C5]) → self::Class5
+    return new self::Class5::_(field1, field2);
+}
+class Class6 extends core::Object {
+  final field core::int field1;
+  final field core::int? field2;
+  final field core::int field3;
+  static final field dynamic _redirecting# = <dynamic>[#C7]/*isLegacy*/;
+  constructor _(core::int field1, {core::int? field2 = #C5, required core::int field3 = #C5}) → self::Class6
+    : self::Class6::field1 = field1, self::Class6::field2 = field2, self::Class6::field3 = field3, super core::Object::•()
+    ;
+  static factory •(core::int field1, {core::int? field2 = #C5, required core::int field3 = #C5}) → self::Class6
+    return new self::Class6::_(field1, field2: field2, field3: field3);
+}
+class Class7a extends core::Object implements self::Class7b {
+  constructor •() → self::Class7a
+    : super core::Object::•()
+    ;
+}
+class Class7b extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C8]/*isLegacy*/;
+  static factory •() → self::Class7b
+    return new self::Class7a::•();
+}
+class Class8a<T extends core::Object? = dynamic> extends core::Object implements self::Class8b<self::Class8a::T%> {
+  constructor •() → self::Class8a<self::Class8a::T%>
+    : super core::Object::•()
+    ;
+}
+class Class8b<T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C9]/*isLegacy*/;
+  static factory •<T extends core::Object? = dynamic>() → self::Class8b<self::Class8b::•::T%>
+    return new self::Class8a::•<self::Class8b::•::T%>();
+}
+static final field core::bool inSoundMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static method main() → dynamic {
+  core::print("inSoundMode: ${self::inSoundMode}");
+  self::testNoArgs();
+  self::testArgs();
+}
+static method testNoArgs() → dynamic {
+  () → self::Class1 f1a = #C10;
+  self::Class1 c1a = f1a(){() → self::Class1};
+  self::expect(true, c1a is{ForNonNullableByDefault} self::Class1);
+  dynamic f1b = #C10;
+  dynamic c1b = f1b{dynamic}.call();
+  self::expect(true, c1b is{ForNonNullableByDefault} self::Class1);
+  self::expect(true, core::identical(f1a, f1b));
+  () → self::Class2 f2a = #C11;
+  self::Class2 c2a = f2a(){() → self::Class2};
+  self::expect(true, c2a is{ForNonNullableByDefault} self::Class2);
+  dynamic f2b = #C11;
+  dynamic c2b = f2b{dynamic}.call();
+  self::expect(true, c2b is{ForNonNullableByDefault} self::Class2);
+  self::expect(true, core::identical(f2a, f2b));
+}
+static method testArgs() → dynamic {
+  (core::int) → self::Class3 f3a = #C12;
+  self::Class3 c3a = f3a(42){(core::int) → self::Class3};
+  self::expect(42, c3a.{self::Class3::field}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:99:8: Error: Too few positional arguments: 1 required, 0 given.
+    f3a(); // error
+       ^" in f3a{<inapplicable>}.();
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:100:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f3a(42, 87); // error
+       ^" in f3a{<inapplicable>}.(42, 87);
+  };
+  dynamic f3b = #C12;
+  dynamic c3b = f3b{dynamic}.call(87);
+  self::expect(87, c3b{dynamic}.field);
+  self::throws(() → dynamic => f3b{dynamic}.call());
+  self::throws(() → dynamic => f3b{dynamic}.call(42, 87));
+  ([core::int?]) → self::Class4 f4a = #C13;
+  self::Class4 c4a = f4a(){([core::int?]) → self::Class4};
+  self::expect(null, c4a.{self::Class4::field}{core::int?});
+  self::Class4 c4b = f4a(42){([core::int?]) → self::Class4};
+  self::expect(42, c4b.{self::Class4::field}{core::int?});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:115:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f4a(42, 87); // error
+       ^" in f4a{<inapplicable>}.(42, 87);
+  };
+  dynamic f4b = #C13;
+  self::throws(() → dynamic => f4b{dynamic}.call(42, 87));
+  (core::int, [core::int?]) → self::Class5 f5a = #C14;
+  self::Class5 c5a = f5a(42){(core::int, [core::int?]) → self::Class5};
+  self::expect(42, c5a.{self::Class5::field1}{core::int});
+  self::expect(null, c5a.{self::Class5::field2}{core::int?});
+  self::Class5 c5b = f5a(87, 42){(core::int, [core::int?]) → self::Class5};
+  self::expect(87, c5b.{self::Class5::field1}{core::int});
+  self::expect(42, c5b.{self::Class5::field2}{core::int?});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:129:8: Error: Too few positional arguments: 1 required, 0 given.
+    f5a(); // error
+       ^" in f5a{<inapplicable>}.();
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:130:8: Error: Too many positional arguments: 2 allowed, but 3 found.
+Try removing the extra positional arguments.
+    f5a(42, 87, 123); // error
+       ^" in f5a{<inapplicable>}.(42, 87, 123);
+  };
+  dynamic f5b = #C14;
+  self::throws(() → dynamic => f5b{dynamic}.call());
+  self::throws(() → dynamic => f5b{dynamic}.call(42, 87, 123));
+  (core::int, {field2: core::int?, required field3: core::int}) → self::Class6 f6a = #C15;
+  self::Class6 c6a = f6a(42, field3: 87){(core::int, {field2: core::int?, required field3: core::int}) → self::Class6};
+  self::expect(42, c6a.{self::Class6::field1}{core::int});
+  self::expect(null, c6a.{self::Class6::field2}{core::int?});
+  self::expect(87, c6a.{self::Class6::field3}{core::int});
+  () → Null {
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:142:8: Error: Too few positional arguments: 1 required, 0 given.
+    f6a(); // error
+       ^" in f6a{<inapplicable>}.();
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:143:8: Error: Required named parameter 'field3' must be provided.
+    f6a(42); // error
+       ^" in f6a{<inapplicable>}.(42);
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:144:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    f6a(42, 87); // error
+       ^" in f6a{<inapplicable>}.(42, 87);
+    invalid-expression "pkg/front_end/testcases/constructor_tearoffs/redirecting_factory_tear_off.dart:145:8: Error: Too few positional arguments: 1 required, 0 given.
+    f6a(field1: 87, field2: 87); // error
+       ^" in f6a{<inapplicable>}.(field1: 87, field2: 87);
+  };
+  self::Class6 c6b = f6a(42, field2: 123, field3: 87){(core::int, {field2: core::int?, required field3: core::int}) → self::Class6};
+  self::expect(42, c6b.{self::Class6::field1}{core::int});
+  self::expect(123, c6b.{self::Class6::field2}{core::int?});
+  self::expect(87, c6b.{self::Class6::field3}{core::int});
+  self::Class6 c6c = f6a(87, field3: 42, field2: 123){(core::int, {field2: core::int?, required field3: core::int}) → self::Class6};
+  self::expect(87, c6c.{self::Class6::field1}{core::int});
+  self::expect(123, c6c.{self::Class6::field2}{core::int?});
+  self::expect(42, c6c.{self::Class6::field3}{core::int});
+  dynamic f6b = #C15;
+  self::throws(() → dynamic => f6b{dynamic}.call());
+  self::throws(() → dynamic => f6b{dynamic}.call(42), inSoundModeOnly: true);
+  self::throws(() → dynamic => f6b{dynamic}.call(42, 87), inSoundModeOnly: true);
+  self::throws(() → dynamic => f6b{dynamic}.call(field1: 87, field2: 87));
+  () → self::Class7b f7a = #C16;
+  self::Class7b c7a = f7a(){() → self::Class7b};
+  self::expect(true, c7a is{ForNonNullableByDefault} self::Class7a);
+  self::expect(true, c7a is{ForNonNullableByDefault} self::Class7b);
+  <T extends core::Object? = dynamic>() → self::Class8b<T%> f8a = #C17;
+  self::Class8b<dynamic> c8a = f8a<dynamic>(){() → self::Class8b<dynamic>};
+  self::expect(true, c8a is{ForNonNullableByDefault} self::Class8a<dynamic>);
+  self::expect(true, c8a is{ForNonNullableByDefault} self::Class8b<dynamic>);
+  self::Class8b<core::int> c8b = f8a<core::int>(){() → self::Class8b<core::int>};
+  self::expect(true, c8b is{ForNonNullableByDefault} self::Class8a<core::int>);
+  self::expect(true, c8b is{ForNonNullableByDefault} self::Class8b<core::int>);
+  self::expect(false, c8b is{ForNonNullableByDefault} self::Class8b<core::String>);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, {core::bool inSoundModeOnly = #C18}) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print("Thrown: ${e}");
+    return;
+  }
+  if(!self::inSoundMode && inSoundModeOnly) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+constants  {
+  #C1 = constructor-tearoff self::Class1::•
+  #C2 = constructor-tearoff self::Class2::named
+  #C3 = constructor-tearoff self::Class3::•
+  #C4 = constructor-tearoff self::Class4::•
+  #C5 = null
+  #C6 = constructor-tearoff self::Class5::•
+  #C7 = constructor-tearoff self::Class6::•
+  #C8 = constructor-tearoff self::Class7b::•
+  #C9 = constructor-tearoff self::Class8b::•
+  #C10 = redirecting-factory-tearoff self::Class1::•
+  #C11 = redirecting-factory-tearoff self::Class2::named
+  #C12 = redirecting-factory-tearoff self::Class3::•
+  #C13 = redirecting-factory-tearoff self::Class4::•
+  #C14 = redirecting-factory-tearoff self::Class5::•
+  #C15 = redirecting-factory-tearoff self::Class6::•
+  #C16 = redirecting-factory-tearoff self::Class7b::•
+  #C17 = redirecting-factory-tearoff self::Class8b::•
+  #C18 = false
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/simple_instantiated_type_literals.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/simple_instantiated_type_literals.dart.weak.modular.expect
new file mode 100644
index 0000000..1e0382a
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/simple_instantiated_type_literals.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method foo() → dynamic
+  return #C1;
+static method bar() → dynamic {
+  core::Type listString = #C2;
+  return listString;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = TypeLiteralConstant(core::List<core::int*>*)
+  #C2 = TypeLiteralConstant(core::List<core::String*>*)
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/simple_proper_rename_identity.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/simple_proper_rename_identity.dart.weak.modular.expect
new file mode 100644
index 0000000..2949323
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/simple_proper_rename_identity.dart.weak.modular.expect
@@ -0,0 +1,77 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/simple_proper_rename_identity.dart:32:18: Error: Constant evaluation error:
+// test4() => const StaticIdentityTest(A4.new, B4.new); // Error.
+//                  ^
+// pkg/front_end/testcases/constructor_tearoffs/simple_proper_rename_identity.dart:26:43: Context: This assertion failed.
+//   const StaticIdentityTest(a, b) : assert(identical(a, b));
+//                                           ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/simple_proper_rename_identity.dart:33:18: Error: Constant evaluation error:
+// test5() => const StaticIdentityTest(A5.new, B5.new); // Error.
+//                  ^
+// pkg/front_end/testcases/constructor_tearoffs/simple_proper_rename_identity.dart:26:43: Context: This assertion failed.
+//   const StaticIdentityTest(a, b) : assert(identical(a, b));
+//                                           ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef B1<T extends core::Object? = dynamic> = self::A1<T%>;
+typedef B2<T extends core::num> = self::A2<T>;
+typedef B3<T extends core::List<core::Object?>, S extends Null> = self::A3<T, S%>;
+typedef B4<T extends core::int> = self::A4<T>;
+typedef B5<unrelated T extends core::List<core::Object?>, unrelated S extends Null> = self::A5<core::List<dynamic>, Never?>;
+class A1<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A1<self::A1::T%>
+    : super core::Object::•()
+    ;
+}
+class A2<T extends core::num> extends core::Object {
+  synthetic constructor •() → self::A2<self::A2::T>
+    : super core::Object::•()
+    ;
+}
+class A3<T extends core::List<dynamic>, S extends Never?> extends core::Object {
+  synthetic constructor •() → self::A3<self::A3::T, self::A3::S%>
+    : super core::Object::•()
+    ;
+}
+class A4<T extends core::num> extends core::Object {
+  synthetic constructor •() → self::A4<self::A4::T>
+    : super core::Object::•()
+    ;
+}
+class A5<T extends core::List<dynamic>, S extends Never?> extends core::Object {
+  synthetic constructor •() → self::A5<self::A5::T, self::A5::S%>
+    : super core::Object::•()
+    ;
+}
+class StaticIdentityTest extends core::Object /*hasConstConstructor*/  {
+  const constructor •(dynamic a, dynamic b) → self::StaticIdentityTest
+    : assert(core::identical(a, b)), super core::Object::•()
+    ;
+}
+static method test1() → dynamic
+  return #C1;
+static method test2() → dynamic
+  return #C1;
+static method test3() → dynamic
+  return #C1;
+static method test4() → dynamic
+  return invalid-expression "This assertion failed.";
+static method test5() → dynamic
+  return invalid-expression "This assertion failed.";
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::StaticIdentityTest {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///simple_proper_rename_identity.dart:
+- StaticIdentityTest. (from org-dartlang-testcase:///simple_proper_rename_identity.dart:26:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/constructor_tearoffs/static_tearoff_from_instantiated_class.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/static_tearoff_from_instantiated_class.dart.weak.modular.expect
new file mode 100644
index 0000000..6f79e9e
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/static_tearoff_from_instantiated_class.dart.weak.modular.expect
@@ -0,0 +1,87 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/static_tearoff_from_instantiated_class.dart:16:33: Error: Cannot access static member on an instantiated generic class.
+// Try removing the type arguments or placing them after the member name.
+//   int Function(int) f4 = A<int>.foo; // Error.
+//                                 ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/static_tearoff_from_instantiated_class.dart:17:19: Error: Cannot access static member on an instantiated generic class.
+// Try removing the type arguments or placing them after the member name.
+//   var f5 = A<int>.foo; // Error.
+//                   ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/static_tearoff_from_instantiated_class.dart:22:34: Error: Cannot access static member on an instantiated generic class.
+// Try removing the type arguments or placing them after the member name.
+//   int Function(int) g4 = D1<int>.foo; // Error.
+//                                  ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/static_tearoff_from_instantiated_class.dart:23:20: Error: Cannot access static member on an instantiated generic class.
+// Try removing the type arguments or placing them after the member name.
+//   var g5 = D1<int>.foo; // Error.
+//                    ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/static_tearoff_from_instantiated_class.dart:28:34: Error: Cannot access static member on an instantiated generic class.
+// Try removing the type arguments or placing them after the member name.
+//   int Function(int) h4 = D2<int>.foo; // Error.
+//                                  ^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/static_tearoff_from_instantiated_class.dart:29:20: Error: Cannot access static member on an instantiated generic class.
+// Try removing the type arguments or placing them after the member name.
+//   var h5 = D2<int>.foo; // Error.
+//                    ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef D1<X extends core::Object? = dynamic> = self::A<X%>;
+typedef D2<X extends core::num> = self::A<X>;
+class A<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+  static method foo<X extends core::Object? = dynamic>(self::A::foo::X% x) → self::A::foo::X%
+    return x;
+}
+static method test() → dynamic {
+  <Y extends core::Object? = dynamic>(Y%) → Y% f1 = #C1;
+  (core::int) → core::int f2 = #C2;
+  (core::int) → core::int f3 = #C2;
+  (core::int) → core::int f4 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/static_tearoff_from_instantiated_class.dart:16:33: Error: Cannot access static member on an instantiated generic class.
+Try removing the type arguments or placing them after the member name.
+  int Function(int) f4 = A<int>.foo; // Error.
+                                ^^^";
+  invalid-type f5 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/static_tearoff_from_instantiated_class.dart:17:19: Error: Cannot access static member on an instantiated generic class.
+Try removing the type arguments or placing them after the member name.
+  var f5 = A<int>.foo; // Error.
+                  ^^^";
+  <Y extends core::Object? = dynamic>(Y%) → Y% g1 = #C1;
+  (core::int) → core::int g2 = #C2;
+  (core::int) → core::int g3 = #C2;
+  (core::int) → core::int g4 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/static_tearoff_from_instantiated_class.dart:22:34: Error: Cannot access static member on an instantiated generic class.
+Try removing the type arguments or placing them after the member name.
+  int Function(int) g4 = D1<int>.foo; // Error.
+                                 ^^^";
+  invalid-type g5 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/static_tearoff_from_instantiated_class.dart:23:20: Error: Cannot access static member on an instantiated generic class.
+Try removing the type arguments or placing them after the member name.
+  var g5 = D1<int>.foo; // Error.
+                   ^^^";
+  <Y extends core::Object? = dynamic>(Y%) → Y% h1 = #C1;
+  (core::int) → core::int h2 = #C2;
+  (core::int) → core::int h3 = #C2;
+  (core::int) → core::int h4 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/static_tearoff_from_instantiated_class.dart:28:34: Error: Cannot access static member on an instantiated generic class.
+Try removing the type arguments or placing them after the member name.
+  int Function(int) h4 = D2<int>.foo; // Error.
+                                 ^^^";
+  invalid-type h5 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/static_tearoff_from_instantiated_class.dart:29:20: Error: Cannot access static member on an instantiated generic class.
+Try removing the type arguments or placing them after the member name.
+  var h5 = D2<int>.foo; // Error.
+                   ^^^";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::A::foo
+  #C2 = instantiation #C1 <core::int*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart.weak.modular.expect
new file mode 100644
index 0000000..f075526
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart.weak.modular.expect
@@ -0,0 +1,141 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart:28:25: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'DA2'.
+// Try changing type arguments so that they conform to the bounds.
+// A Function() test5() => DA2<String>.new; // Error.
+//                         ^
+// pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart:15:13: Context: This is the type variable whose bound isn't conformed to.
+// typedef DA2<X extends num> = A;
+//             ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart:33:30: Error: A value of type 'B<String> Function()' can't be returned from a function with return type 'B<num> Function()'.
+//  - 'B' is from 'pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart'.
+// B<num> Function() test9() => DB1.new; // Error.
+//                              ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart:42:32: Error: A value of type 'B<X> Function<X extends num>()' can't be assigned to a variable of type 'B<Y> Function<Y>()'.
+//  - 'B' is from 'pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart'.
+// B<Y> Function<Y>() test17() => DB2.new; // Error.
+//                                ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart:42:32: Error: A value of type 'B<X> Function<X extends num>()' can't be returned from a function with return type 'B<Y> Function<Y>()'.
+//  - 'B' is from 'pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart'.
+// B<Y> Function<Y>() test17() => DB2.new; // Error.
+//                                ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart:49:35: Error: A value of type 'B<X> Function<X extends num, Y extends String>()' can't be assigned to a variable of type 'B<Y> Function<Y, Z>()'.
+//  - 'B' is from 'pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart'.
+// B<Y> Function<Y, Z>() test23() => DB3.new; // Error.
+//                                   ^
+//
+// pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart:49:35: Error: A value of type 'B<X> Function<X extends num, Y extends String>()' can't be returned from a function with return type 'B<Y> Function<Y, Z>()'.
+//  - 'B' is from 'pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart'.
+// B<Y> Function<Y, Z>() test23() => DB3.new; // Error.
+//                                   ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef DA1 = self::A;
+typedef DA2<unrelated X extends core::num> = self::A;
+typedef DB1 = self::B<core::String>;
+typedef DB2<X extends core::num> = self::B<X>;
+typedef DB3<X extends core::num, unrelated Y extends core::String> = self::B<X>;
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class B<X extends core::Object? = dynamic> extends core::Object {
+  constructor •() → self::B<self::B::X%>
+    : super core::Object::•()
+    ;
+  constructor foo() → self::B<self::B::X%>
+    : super core::Object::•()
+    ;
+  static factory bar<X extends core::Object? = dynamic>() → self::B<self::B::bar::X%>
+    return new self::B::•<self::B::bar::X%>();
+}
+static method test1() → () → self::A
+  return #C1;
+static method test2() → () → self::A
+  return #C1;
+static method test3() → () → self::A
+  return #C2;
+static method test4() → () → self::A
+  return #C2;
+static method test5() → () → self::A
+  return #C1;
+static method test6() → () → self::A
+  return #C1;
+static method test7() → () → self::B<core::String>
+  return #C4;
+static method test8() → () → self::B<core::String>
+  return #C4;
+static method test9() → () → self::B<core::num>
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart:33:30: Error: A value of type 'B<String> Function()' can't be returned from a function with return type 'B<num> Function()'.
+ - 'B' is from 'pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart'.
+B<num> Function() test9() => DB1.new; // Error.
+                             ^" in #C4 as{TypeError,ForNonNullableByDefault} () → self::B<core::num>;
+static method test10() → () → self::B<core::String>
+  return #C6;
+static method test11() → () → self::B<core::String>
+  return #C8;
+static method test12() → () → self::B<core::num>
+  return #C9;
+static method test13() → () → self::B<core::num>
+  return #C10;
+static method test14() → () → self::B<core::num>
+  return #C11;
+static method test15() → () → self::B<core::num>
+  return #C9;
+static method test16() → <Y extends core::num = dynamic>() → self::B<Y>
+  return #C12;
+static method test17() → <Y extends core::Object? = dynamic>() → self::B<Y%>
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart:42:32: Error: A value of type 'B<X> Function<X extends num>()' can't be returned from a function with return type 'B<Y> Function<Y>()'.
+ - 'B' is from 'pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart'.
+B<Y> Function<Y>() test17() => DB2.new; // Error.
+                               ^" in invalid-expression "pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart:42:32: Error: A value of type 'B<X> Function<X extends num>()' can't be assigned to a variable of type 'B<Y> Function<Y>()'.
+ - 'B' is from 'pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart'.
+B<Y> Function<Y>() test17() => DB2.new; // Error.
+                               ^" in #C12 as{TypeError,ForNonNullableByDefault} <Y extends core::Object? = dynamic>() → self::B<Y%> as{TypeError,ForNonNullableByDefault} <Y extends core::Object? = dynamic>() → self::B<Y%>;
+static method test18() → () → self::B<core::num>
+  return #C9;
+static method test19() → () → self::B<core::num>
+  return #C10;
+static method test20() → () → self::B<core::num>
+  return #C11;
+static method test21() → () → self::B<core::num>
+  return #C9;
+static method test22() → <Y extends core::num = dynamic, Z extends core::String = dynamic>() → self::B<Y>
+  return #C13;
+static method test23() → <Y extends core::Object? = dynamic, Z extends core::Object? = dynamic>() → self::B<Y%>
+  return invalid-expression "pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart:49:35: Error: A value of type 'B<X> Function<X extends num, Y extends String>()' can't be returned from a function with return type 'B<Y> Function<Y, Z>()'.
+ - 'B' is from 'pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart'.
+B<Y> Function<Y, Z>() test23() => DB3.new; // Error.
+                                  ^" in invalid-expression "pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart:49:35: Error: A value of type 'B<X> Function<X extends num, Y extends String>()' can't be assigned to a variable of type 'B<Y> Function<Y, Z>()'.
+ - 'B' is from 'pkg/front_end/testcases/constructor_tearoffs/typedef_tearoffs.dart'.
+B<Y> Function<Y, Z>() test23() => DB3.new; // Error.
+                                  ^" in #C13 as{TypeError,ForNonNullableByDefault} <Y extends core::Object? = dynamic, Z extends core::Object? = dynamic>() → self::B<Y%> as{TypeError,ForNonNullableByDefault} <Y extends core::Object? = dynamic, Z extends core::Object? = dynamic>() → self::B<Y%>;
+static method test24() → () → self::B<core::String>
+  return #C14;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::A::•
+  #C2 = instantiation #C1 <>
+  #C3 = constructor-tearoff self::B::•
+  #C4 = instantiation #C3 <core::String*>
+  #C5 = constructor-tearoff self::B::foo
+  #C6 = instantiation #C5 <core::String*>
+  #C7 = constructor-tearoff self::B::bar
+  #C8 = instantiation #C7 <core::String*>
+  #C9 = instantiation #C3 <core::num*>
+  #C10 = instantiation #C5 <core::num*>
+  #C11 = instantiation #C7 <core::num*>
+  #C12 = typedef-tearoff <X extends core::num>.(#C3<X>)
+  #C13 = typedef-tearoff <X extends core::num, unrelated Y extends core::String>.(#C3<X>)
+  #C14 = instantiation #C3 <Never*>
+}
diff --git a/pkg/front_end/testcases/constructor_tearoffs/unnamed_constructor.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/unnamed_constructor.dart.weak.modular.expect
new file mode 100644
index 0000000..34009a6
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/unnamed_constructor.dart.weak.modular.expect
@@ -0,0 +1,72 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1, #C2]/*isLegacy*/;
+  constructor •() → self::A
+    : super core::Object::•()
+    ;
+  constructor redirecting() → self::A
+    : this self::A::•()
+    ;
+  static factory redirectingFactory() → self::A
+    return new self::A::•();
+  static factory redirectingFactoryChild() → self::A
+    return new self::B::•();
+}
+class B extends self::A {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+}
+class C extends core::Object /*hasConstConstructor*/  {
+  final field core::int x;
+  const constructor •(core::int x) → self::C
+    : self::C::x = x, super core::Object::•()
+    ;
+}
+class D extends self::C {
+  constructor •(core::int x) → self::D
+    : super self::C::•(x.{core::num::*}(2){(core::num) → core::int})
+    ;
+}
+static method test() → dynamic {
+  new self::D::•(1);
+  #C4;
+  new self::C::•(1);
+  () → self::A f1 = #C5;
+  () → self::B f2 = #C6;
+  (core::int) → self::C f3 = #C7;
+  (core::int) → self::D f4 = #C8;
+  f1(){() → self::A};
+  f2(){() → self::B};
+  f3(1){(core::int) → self::C};
+  f4(1){(core::int) → self::D};
+  () → self::A g1 = #C5;
+  () → self::B g2 = #C6;
+  (core::int) → self::C g3 = #C7;
+  (core::int) → self::D g4 = #C8;
+  g1(){() → self::A};
+  g2(){() → self::B};
+  g3(1){(core::int) → self::C};
+  g4(1){(core::int) → self::D};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::A::redirectingFactory
+  #C2 = constructor-tearoff self::A::redirectingFactoryChild
+  #C3 = 1
+  #C4 = self::C {x:#C3}
+  #C5 = constructor-tearoff self::A::•
+  #C6 = constructor-tearoff self::B::•
+  #C7 = constructor-tearoff self::C::•
+  #C8 = constructor-tearoff self::D::•
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///unnamed_constructor.dart:
+- C. (from org-dartlang-testcase:///unnamed_constructor.dart:16:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart.weak.modular.expect b/pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart.weak.modular.expect
new file mode 100644
index 0000000..920c962
--- /dev/null
+++ b/pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart.weak.modular.expect
@@ -0,0 +1,858 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:12:26: Error: Superclass has no constructor named 'Super'.
+//   Class.constructor1() : super();
+//                          ^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:13:26: Error: Superclass has no constructor named 'Super.unresolved'.
+//   Class.constructor2() : super.unresolved();
+//                          ^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:14:26: Error: Couldn't find constructor 'Class'.
+//   Class.constructor3() : this();
+//                          ^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:15:26: Error: Couldn't find constructor 'Class.unresolved'.
+//   Class.constructor4() : this.unresolved();
+//                          ^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:23:3: Error: Method not found: 'UnresolvedClass'.
+//   UnresolvedClass();
+//   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:24:7: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new UnresolvedClass();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:25:9: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const UnresolvedClass();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:27:3: Error: Undefined name 'UnresolvedClass'.
+//   UnresolvedClass.unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:28:7: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+//   new UnresolvedClass.unresolvedConstructor();
+//       ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:29:9: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+//   const UnresolvedClass.unresolvedConstructor();
+//         ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:30:3: Error: Undefined name 'UnresolvedClass'.
+//   UnresolvedClass /**/ .unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:31:7: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+//   new UnresolvedClass. /**/ unresolvedConstructor();
+//       ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:32:9: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+//   const UnresolvedClass /**/ .unresolvedConstructor();
+//         ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:34:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix.UnresolvedClass();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:35:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   new unresolved_prefix.UnresolvedClass();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:36:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   const unresolved_prefix.UnresolvedClass();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:37:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix. /**/ UnresolvedClass();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:38:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   new unresolved_prefix /**/ .UnresolvedClass();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:39:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   const unresolved_prefix. /**/ UnresolvedClass();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:41:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix.UnresolvedClass.unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:42:41: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   new unresolved_prefix.UnresolvedClass.unresolvedConstructor();
+//                                         ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:43:43: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   const unresolved_prefix.UnresolvedClass.unresolvedConstructor();
+//                                           ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:44:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix /**/ .UnresolvedClass.unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:45:47: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   new unresolved_prefix.UnresolvedClass /**/ .unresolvedConstructor();
+//                                               ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:46:55: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   const unresolved_prefix. /**/ UnresolvedClass. /**/ unresolvedConstructor();
+//                                                       ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:48:3: Error: Method not found: 'UnresolvedClass'.
+//   UnresolvedClass<int>();
+//   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:49:7: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new UnresolvedClass<int>();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:50:9: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const UnresolvedClass<int>();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:51:3: Error: Method not found: 'UnresolvedClass'.
+//   UnresolvedClass /**/ <int>();
+//   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:52:7: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new UnresolvedClass<int> /**/ ();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:53:9: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const UnresolvedClass /**/ <int>();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:55:3: Error: Couldn't find constructor 'UnresolvedClass'.
+//   UnresolvedClass<int>.unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:56:7: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new UnresolvedClass<int>.unresolvedConstructor();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:57:9: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const UnresolvedClass<int>.unresolvedConstructor();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:58:3: Error: Couldn't find constructor 'UnresolvedClass'.
+//   UnresolvedClass /**/ <int>.unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:59:7: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new UnresolvedClass<int> /**/ .unresolvedConstructor();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:60:9: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const UnresolvedClass<int>. /**/ unresolvedConstructor();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:62:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix.UnresolvedClass<int>();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:63:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   new unresolved_prefix.UnresolvedClass<int>();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:64:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   const unresolved_prefix.UnresolvedClass<int>();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:65:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix /**/ .UnresolvedClass<int>();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:66:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   new unresolved_prefix.UnresolvedClass /**/ <int>();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:67:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   const unresolved_prefix.UnresolvedClass<int> /**/ ();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:69:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:70:46: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   new unresolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+//                                              ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:71:48: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   const unresolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+//                                                ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:72:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix /**/ .UnresolvedClass<int>.unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:73:52: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   new unresolved_prefix.UnresolvedClass /**/ <int>.unresolvedConstructor();
+//                                                    ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:74:54: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   const unresolved_prefix.UnresolvedClass<int>. /**/ unresolvedConstructor();
+//                                                      ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:76:3: Error: Couldn't find constructor 'ResolvedClass'.
+//   ResolvedClass();
+//   ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:77:7: Error: Couldn't find constructor 'ResolvedClass'.
+//   new ResolvedClass();
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:78:9: Error: Couldn't find constructor 'ResolvedClass'.
+//   const ResolvedClass();
+//         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:80:17: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+//   ResolvedClass.unresolvedConstructor();
+//                 ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:81:21: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new ResolvedClass.unresolvedConstructor();
+//                     ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:82:23: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const ResolvedClass.unresolvedConstructor();
+//                       ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:83:23: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+//   ResolvedClass /**/ .unresolvedConstructor();
+//                       ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:84:27: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new ResolvedClass. /**/ unresolvedConstructor();
+//                           ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:85:29: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const ResolvedClass /**/ .unresolvedConstructor();
+//                             ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:87:19: Error: Method not found: 'UnresolvedClass'.
+//   resolved_prefix.UnresolvedClass();
+//                   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:88:23: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix.UnresolvedClass();
+//                       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:89:25: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const resolved_prefix.UnresolvedClass();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:90:25: Error: Method not found: 'UnresolvedClass'.
+//   resolved_prefix. /**/ UnresolvedClass();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:91:29: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix /**/ .UnresolvedClass();
+//                             ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:92:31: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const resolved_prefix. /**/ UnresolvedClass();
+//                               ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:94:19: Error: Couldn't find constructor 'ResolvedClass'.
+//   resolved_prefix.ResolvedClass();
+//                   ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:95:7: Error: Couldn't find constructor 'ResolvedClass'.
+//   new resolved_prefix.ResolvedClass();
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:96:9: Error: Couldn't find constructor 'ResolvedClass'.
+//   const resolved_prefix.ResolvedClass();
+//         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:97:25: Error: Couldn't find constructor 'ResolvedClass'.
+//   resolved_prefix. /**/ ResolvedClass();
+//                         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:98:7: Error: Couldn't find constructor 'ResolvedClass'.
+//   new resolved_prefix /**/ .ResolvedClass();
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:99:9: Error: Couldn't find constructor 'ResolvedClass'.
+//   const resolved_prefix. /**/ ResolvedClass();
+//         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:101:19: Error: Undefined name 'UnresolvedClass'.
+//   resolved_prefix.UnresolvedClass.unresolvedConstructor();
+//                   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:102:23: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix.UnresolvedClass.unresolvedConstructor();
+//                       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:103:25: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const resolved_prefix.UnresolvedClass.unresolvedConstructor();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:104:25: Error: Undefined name 'UnresolvedClass'.
+//   resolved_prefix /**/ .UnresolvedClass.unresolvedConstructor();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:105:23: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix.UnresolvedClass /**/ .unresolvedConstructor();
+//                       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:106:31: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const resolved_prefix. /**/ UnresolvedClass. /**/ unresolvedConstructor();
+//                               ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:108:33: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+//   resolved_prefix.ResolvedClass.unresolvedConstructor();
+//                                 ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:109:37: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new resolved_prefix.ResolvedClass.unresolvedConstructor();
+//                                     ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:110:39: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const resolved_prefix.ResolvedClass.unresolvedConstructor();
+//                                       ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:111:39: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+//   resolved_prefix /**/ .ResolvedClass.unresolvedConstructor();
+//                                       ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:112:43: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new resolved_prefix.ResolvedClass /**/ .unresolvedConstructor();
+//                                           ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:113:51: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const resolved_prefix. /**/ ResolvedClass. /**/ unresolvedConstructor();
+//                                                   ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:115:3: Error: Couldn't find constructor 'ResolvedClass'.
+//   ResolvedClass<int>();
+//   ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:116:7: Error: Couldn't find constructor 'ResolvedClass'.
+//   new ResolvedClass<int>();
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:117:9: Error: Couldn't find constructor 'ResolvedClass'.
+//   const ResolvedClass<int>();
+//         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:118:3: Error: Couldn't find constructor 'ResolvedClass'.
+//   ResolvedClass /**/ <int>();
+//   ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:119:7: Error: Couldn't find constructor 'ResolvedClass'.
+//   new ResolvedClass /**/ <int>();
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:120:9: Error: Couldn't find constructor 'ResolvedClass'.
+//   const ResolvedClass /**/ <int>();
+//         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:122:22: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   ResolvedClass<int>.unresolvedConstructor();
+//                      ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:123:26: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new ResolvedClass<int>.unresolvedConstructor();
+//                          ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:124:28: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const ResolvedClass<int>.unresolvedConstructor();
+//                            ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:125:28: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   ResolvedClass<int> /**/ .unresolvedConstructor();
+//                            ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:126:32: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new ResolvedClass<int>. /**/ unresolvedConstructor();
+//                                ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:127:34: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const ResolvedClass /**/ <int>.unresolvedConstructor();
+//                                  ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:129:19: Error: Method not found: 'UnresolvedClass'.
+//   resolved_prefix.UnresolvedClass<int>();
+//                   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:130:23: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix.UnresolvedClass<int>();
+//                       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:131:25: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const resolved_prefix.UnresolvedClass<int>();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:132:25: Error: Method not found: 'UnresolvedClass'.
+//   resolved_prefix. /**/ UnresolvedClass<int>();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:133:23: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix.UnresolvedClass /**/ <int>();
+//                       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:134:25: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const resolved_prefix.UnresolvedClass<int> /**/ ();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:136:19: Error: Couldn't find constructor 'ResolvedClass'.
+//   resolved_prefix.ResolvedClass<int>();
+//                   ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:137:7: Error: Couldn't find constructor 'ResolvedClass'.
+//   new resolved_prefix.ResolvedClass<int>();
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:138:9: Error: Couldn't find constructor 'ResolvedClass'.
+//   const resolved_prefix.ResolvedClass<int>();
+//         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:139:25: Error: Couldn't find constructor 'ResolvedClass'.
+//   resolved_prefix. /**/ ResolvedClass<int>();
+//                         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:140:7: Error: Couldn't find constructor 'ResolvedClass'.
+//   new resolved_prefix.ResolvedClass /**/ <int>();
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:141:9: Error: Couldn't find constructor 'ResolvedClass'.
+//   const resolved_prefix.ResolvedClass<int> /**/ ();
+//         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:143:19: Error: Couldn't find constructor 'UnresolvedClass'.
+//   resolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+//                   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:144:23: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+//                       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:145:25: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const resolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:146:25: Error: Couldn't find constructor 'UnresolvedClass'.
+//   resolved_prefix /**/ .UnresolvedClass<int>.unresolvedConstructor();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:147:23: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix.UnresolvedClass<int> /**/ .unresolvedConstructor();
+//                       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:149:14: Error: Couldn't find constructor 'UnresolvedClass'.
+//       . /**/ UnresolvedClass<int>. /**/ unresolvedConstructor();
+//              ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:151:38: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   resolved_prefix.ResolvedClass<int>.unresolvedConstructor();
+//                                      ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:152:42: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new resolved_prefix.ResolvedClass<int>.unresolvedConstructor();
+//                                          ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:153:44: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const resolved_prefix.ResolvedClass<int>.unresolvedConstructor();
+//                                            ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:154:44: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   resolved_prefix /**/ .ResolvedClass<int>.unresolvedConstructor();
+//                                            ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:155:48: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new resolved_prefix.ResolvedClass<int> /**/ .unresolvedConstructor();
+//                                                ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:156:56: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const resolved_prefix. /**/ ResolvedClass<int>. /**/ unresolvedConstructor();
+//                                                        ^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///unresolved_constructor_invocation.dart" as resolved_prefix;
+
+class Super extends core::Object {
+  constructor named() → self::Super
+    : super core::Object::•()
+    ;
+}
+class Class extends self::Super {
+  constructor constructor1() → self::Class
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:12:26: Error: Superclass has no constructor named 'Super'.
+  Class.constructor1() : super();
+                         ^^^^^"
+    ;
+  constructor constructor2() → self::Class
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:13:26: Error: Superclass has no constructor named 'Super.unresolved'.
+  Class.constructor2() : super.unresolved();
+                         ^^^^^"
+    ;
+  constructor constructor3() → self::Class
+    : final dynamic #t3 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:14:26: Error: Couldn't find constructor 'Class'.
+  Class.constructor3() : this();
+                         ^^^^"
+    ;
+  constructor constructor4() → self::Class
+    : final dynamic #t4 = invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:15:26: Error: Couldn't find constructor 'Class.unresolved'.
+  Class.constructor4() : this.unresolved();
+                         ^^^^"
+    ;
+}
+class ResolvedClass<T extends core::Object? = dynamic> extends core::Object {
+  constructor named() → self::ResolvedClass<self::ResolvedClass::T%>
+    : super core::Object::•()
+    ;
+}
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:23:3: Error: Method not found: 'UnresolvedClass'.
+  UnresolvedClass();
+  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:24:7: Error: Couldn't find constructor 'UnresolvedClass'.
+  new UnresolvedClass();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:25:9: Error: Couldn't find constructor 'UnresolvedClass'.
+  const UnresolvedClass();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:27:3: Error: Undefined name 'UnresolvedClass'.
+  UnresolvedClass.unresolvedConstructor();
+  ^^^^^^^^^^^^^^^"{dynamic}.unresolvedConstructor();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:28:7: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+  new UnresolvedClass.unresolvedConstructor();
+      ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:29:9: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+  const UnresolvedClass.unresolvedConstructor();
+        ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:30:3: Error: Undefined name 'UnresolvedClass'.
+  UnresolvedClass /**/ .unresolvedConstructor();
+  ^^^^^^^^^^^^^^^"{dynamic}.unresolvedConstructor();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:31:7: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+  new UnresolvedClass. /**/ unresolvedConstructor();
+      ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:32:9: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+  const UnresolvedClass /**/ .unresolvedConstructor();
+        ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:34:3: Error: Undefined name 'unresolved_prefix'.
+  unresolved_prefix.UnresolvedClass();
+  ^^^^^^^^^^^^^^^^^"{dynamic}.UnresolvedClass();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:35:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  new unresolved_prefix.UnresolvedClass();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:36:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  const unresolved_prefix.UnresolvedClass();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:37:3: Error: Undefined name 'unresolved_prefix'.
+  unresolved_prefix. /**/ UnresolvedClass();
+  ^^^^^^^^^^^^^^^^^"{dynamic}.UnresolvedClass();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:38:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  new unresolved_prefix /**/ .UnresolvedClass();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:39:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  const unresolved_prefix. /**/ UnresolvedClass();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:41:3: Error: Undefined name 'unresolved_prefix'.
+  unresolved_prefix.UnresolvedClass.unresolvedConstructor();
+  ^^^^^^^^^^^^^^^^^"{<invalid>}.UnresolvedClass{dynamic}.unresolvedConstructor();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:42:41: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  new unresolved_prefix.UnresolvedClass.unresolvedConstructor();
+                                        ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:43:43: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  const unresolved_prefix.UnresolvedClass.unresolvedConstructor();
+                                          ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:44:3: Error: Undefined name 'unresolved_prefix'.
+  unresolved_prefix /**/ .UnresolvedClass.unresolvedConstructor();
+  ^^^^^^^^^^^^^^^^^"{<invalid>}.UnresolvedClass{dynamic}.unresolvedConstructor();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:45:47: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  new unresolved_prefix.UnresolvedClass /**/ .unresolvedConstructor();
+                                              ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:46:55: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  const unresolved_prefix. /**/ UnresolvedClass. /**/ unresolvedConstructor();
+                                                      ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:48:3: Error: Method not found: 'UnresolvedClass'.
+  UnresolvedClass<int>();
+  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:49:7: Error: Couldn't find constructor 'UnresolvedClass'.
+  new UnresolvedClass<int>();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:50:9: Error: Couldn't find constructor 'UnresolvedClass'.
+  const UnresolvedClass<int>();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:51:3: Error: Method not found: 'UnresolvedClass'.
+  UnresolvedClass /**/ <int>();
+  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:52:7: Error: Couldn't find constructor 'UnresolvedClass'.
+  new UnresolvedClass<int> /**/ ();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:53:9: Error: Couldn't find constructor 'UnresolvedClass'.
+  const UnresolvedClass /**/ <int>();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:55:3: Error: Couldn't find constructor 'UnresolvedClass'.
+  UnresolvedClass<int>.unresolvedConstructor();
+  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:56:7: Error: Couldn't find constructor 'UnresolvedClass'.
+  new UnresolvedClass<int>.unresolvedConstructor();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:57:9: Error: Couldn't find constructor 'UnresolvedClass'.
+  const UnresolvedClass<int>.unresolvedConstructor();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:58:3: Error: Couldn't find constructor 'UnresolvedClass'.
+  UnresolvedClass /**/ <int>.unresolvedConstructor();
+  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:59:7: Error: Couldn't find constructor 'UnresolvedClass'.
+  new UnresolvedClass<int> /**/ .unresolvedConstructor();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:60:9: Error: Couldn't find constructor 'UnresolvedClass'.
+  const UnresolvedClass<int>. /**/ unresolvedConstructor();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:62:3: Error: Undefined name 'unresolved_prefix'.
+  unresolved_prefix.UnresolvedClass<int>();
+  ^^^^^^^^^^^^^^^^^"{dynamic}.UnresolvedClass<core::int>();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:63:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  new unresolved_prefix.UnresolvedClass<int>();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:64:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  const unresolved_prefix.UnresolvedClass<int>();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:65:3: Error: Undefined name 'unresolved_prefix'.
+  unresolved_prefix /**/ .UnresolvedClass<int>();
+  ^^^^^^^^^^^^^^^^^"{dynamic}.UnresolvedClass<core::int>();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:66:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  new unresolved_prefix.UnresolvedClass /**/ <int>();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:67:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  const unresolved_prefix.UnresolvedClass<int> /**/ ();
+        ^^^^^^^^^^^^^^^";
+  (invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:69:3: Error: Undefined name 'unresolved_prefix'.
+  unresolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+  ^^^^^^^^^^^^^^^^^"{<invalid>}.UnresolvedClass<core::int>){dynamic}.unresolvedConstructor();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:70:46: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  new unresolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+                                             ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:71:48: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  const unresolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+                                               ^^^^^^^^^^^^^^^^^^^^^";
+  (invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:72:3: Error: Undefined name 'unresolved_prefix'.
+  unresolved_prefix /**/ .UnresolvedClass<int>.unresolvedConstructor();
+  ^^^^^^^^^^^^^^^^^"{<invalid>}.UnresolvedClass<core::int>){dynamic}.unresolvedConstructor();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:73:52: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  new unresolved_prefix.UnresolvedClass /**/ <int>.unresolvedConstructor();
+                                                   ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:74:54: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  const unresolved_prefix.UnresolvedClass<int>. /**/ unresolvedConstructor();
+                                                     ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:76:3: Error: Couldn't find constructor 'ResolvedClass'.
+  ResolvedClass();
+  ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:77:7: Error: Couldn't find constructor 'ResolvedClass'.
+  new ResolvedClass();
+      ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:78:9: Error: Couldn't find constructor 'ResolvedClass'.
+  const ResolvedClass();
+        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:80:17: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+  ResolvedClass.unresolvedConstructor();
+                ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:81:21: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new ResolvedClass.unresolvedConstructor();
+                    ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:82:23: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const ResolvedClass.unresolvedConstructor();
+                      ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:83:23: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+  ResolvedClass /**/ .unresolvedConstructor();
+                      ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:84:27: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new ResolvedClass. /**/ unresolvedConstructor();
+                          ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:85:29: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const ResolvedClass /**/ .unresolvedConstructor();
+                            ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:87:19: Error: Method not found: 'UnresolvedClass'.
+  resolved_prefix.UnresolvedClass();
+                  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:88:23: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix.UnresolvedClass();
+                      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:89:25: Error: Couldn't find constructor 'UnresolvedClass'.
+  const resolved_prefix.UnresolvedClass();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:90:25: Error: Method not found: 'UnresolvedClass'.
+  resolved_prefix. /**/ UnresolvedClass();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:91:29: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix /**/ .UnresolvedClass();
+                            ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:92:31: Error: Couldn't find constructor 'UnresolvedClass'.
+  const resolved_prefix. /**/ UnresolvedClass();
+                              ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:94:19: Error: Couldn't find constructor 'ResolvedClass'.
+  resolved_prefix.ResolvedClass();
+                  ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:95:7: Error: Couldn't find constructor 'ResolvedClass'.
+  new resolved_prefix.ResolvedClass();
+      ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:96:9: Error: Couldn't find constructor 'ResolvedClass'.
+  const resolved_prefix.ResolvedClass();
+        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:97:25: Error: Couldn't find constructor 'ResolvedClass'.
+  resolved_prefix. /**/ ResolvedClass();
+                        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:98:7: Error: Couldn't find constructor 'ResolvedClass'.
+  new resolved_prefix /**/ .ResolvedClass();
+      ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:99:9: Error: Couldn't find constructor 'ResolvedClass'.
+  const resolved_prefix. /**/ ResolvedClass();
+        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:101:19: Error: Undefined name 'UnresolvedClass'.
+  resolved_prefix.UnresolvedClass.unresolvedConstructor();
+                  ^^^^^^^^^^^^^^^"{dynamic}.unresolvedConstructor();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:102:23: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix.UnresolvedClass.unresolvedConstructor();
+                      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:103:25: Error: Couldn't find constructor 'UnresolvedClass'.
+  const resolved_prefix.UnresolvedClass.unresolvedConstructor();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:104:25: Error: Undefined name 'UnresolvedClass'.
+  resolved_prefix /**/ .UnresolvedClass.unresolvedConstructor();
+                        ^^^^^^^^^^^^^^^"{dynamic}.unresolvedConstructor();
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:105:23: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix.UnresolvedClass /**/ .unresolvedConstructor();
+                      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:106:31: Error: Couldn't find constructor 'UnresolvedClass'.
+  const resolved_prefix. /**/ UnresolvedClass. /**/ unresolvedConstructor();
+                              ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:108:33: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+  resolved_prefix.ResolvedClass.unresolvedConstructor();
+                                ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:109:37: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new resolved_prefix.ResolvedClass.unresolvedConstructor();
+                                    ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:110:39: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const resolved_prefix.ResolvedClass.unresolvedConstructor();
+                                      ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:111:39: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+  resolved_prefix /**/ .ResolvedClass.unresolvedConstructor();
+                                      ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:112:43: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new resolved_prefix.ResolvedClass /**/ .unresolvedConstructor();
+                                          ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:113:51: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const resolved_prefix. /**/ ResolvedClass. /**/ unresolvedConstructor();
+                                                  ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:115:3: Error: Couldn't find constructor 'ResolvedClass'.
+  ResolvedClass<int>();
+  ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:116:7: Error: Couldn't find constructor 'ResolvedClass'.
+  new ResolvedClass<int>();
+      ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:117:9: Error: Couldn't find constructor 'ResolvedClass'.
+  const ResolvedClass<int>();
+        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:118:3: Error: Couldn't find constructor 'ResolvedClass'.
+  ResolvedClass /**/ <int>();
+  ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:119:7: Error: Couldn't find constructor 'ResolvedClass'.
+  new ResolvedClass /**/ <int>();
+      ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:120:9: Error: Couldn't find constructor 'ResolvedClass'.
+  const ResolvedClass /**/ <int>();
+        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:122:22: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  ResolvedClass<int>.unresolvedConstructor();
+                     ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:123:26: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new ResolvedClass<int>.unresolvedConstructor();
+                         ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:124:28: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const ResolvedClass<int>.unresolvedConstructor();
+                           ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:125:28: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  ResolvedClass<int> /**/ .unresolvedConstructor();
+                           ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:126:32: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new ResolvedClass<int>. /**/ unresolvedConstructor();
+                               ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:127:34: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const ResolvedClass /**/ <int>.unresolvedConstructor();
+                                 ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:129:19: Error: Method not found: 'UnresolvedClass'.
+  resolved_prefix.UnresolvedClass<int>();
+                  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:130:23: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix.UnresolvedClass<int>();
+                      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:131:25: Error: Couldn't find constructor 'UnresolvedClass'.
+  const resolved_prefix.UnresolvedClass<int>();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:132:25: Error: Method not found: 'UnresolvedClass'.
+  resolved_prefix. /**/ UnresolvedClass<int>();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:133:23: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix.UnresolvedClass /**/ <int>();
+                      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:134:25: Error: Couldn't find constructor 'UnresolvedClass'.
+  const resolved_prefix.UnresolvedClass<int> /**/ ();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:136:19: Error: Couldn't find constructor 'ResolvedClass'.
+  resolved_prefix.ResolvedClass<int>();
+                  ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:137:7: Error: Couldn't find constructor 'ResolvedClass'.
+  new resolved_prefix.ResolvedClass<int>();
+      ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:138:9: Error: Couldn't find constructor 'ResolvedClass'.
+  const resolved_prefix.ResolvedClass<int>();
+        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:139:25: Error: Couldn't find constructor 'ResolvedClass'.
+  resolved_prefix. /**/ ResolvedClass<int>();
+                        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:140:7: Error: Couldn't find constructor 'ResolvedClass'.
+  new resolved_prefix.ResolvedClass /**/ <int>();
+      ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:141:9: Error: Couldn't find constructor 'ResolvedClass'.
+  const resolved_prefix.ResolvedClass<int> /**/ ();
+        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:143:19: Error: Couldn't find constructor 'UnresolvedClass'.
+  resolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+                  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:144:23: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+                      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:145:25: Error: Couldn't find constructor 'UnresolvedClass'.
+  const resolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:146:25: Error: Couldn't find constructor 'UnresolvedClass'.
+  resolved_prefix /**/ .UnresolvedClass<int>.unresolvedConstructor();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:147:23: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix.UnresolvedClass<int> /**/ .unresolvedConstructor();
+                      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:149:14: Error: Couldn't find constructor 'UnresolvedClass'.
+      . /**/ UnresolvedClass<int>. /**/ unresolvedConstructor();
+             ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:151:38: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  resolved_prefix.ResolvedClass<int>.unresolvedConstructor();
+                                     ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:152:42: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new resolved_prefix.ResolvedClass<int>.unresolvedConstructor();
+                                         ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:153:44: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const resolved_prefix.ResolvedClass<int>.unresolvedConstructor();
+                                           ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:154:44: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  resolved_prefix /**/ .ResolvedClass<int>.unresolvedConstructor();
+                                           ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:155:48: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new resolved_prefix.ResolvedClass<int> /**/ .unresolvedConstructor();
+                                               ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/constructor_tearoffs/unresolved_constructor_invocation.dart:156:56: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const resolved_prefix. /**/ ResolvedClass<int>. /**/ unresolvedConstructor();
+                                                       ^^^^^^^^^^^^^^^^^^^^^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/dart2js/conditional_import.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/conditional_import.dart.weak.modular.expect
new file mode 100644
index 0000000..5f33ec1
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/conditional_import.dart.weak.modular.expect
@@ -0,0 +1,84 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/dart2js/conditional_import.dart:18:11: Error: The getter 'readyState' isn't defined for the class 'HttpRequest'.
+//  - 'HttpRequest' is from 'dart:_http'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'readyState'.
+//   request.readyState; // ok (from dart:html)
+//           ^^^^^^^^^^
+//
+// pkg/front_end/testcases/dart2js/conditional_import.dart:23:11: Error: The getter 'certificate' isn't defined for the class 'HttpRequest'.
+//  - 'HttpRequest' is from 'pkg/front_end/testcases/dart2js/conditional_import.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'certificate'.
+//   request.certificate; // error
+//           ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/dart2js/conditional_import.dart:24:11: Error: The getter 'response' isn't defined for the class 'HttpRequest'.
+//  - 'HttpRequest' is from 'pkg/front_end/testcases/dart2js/conditional_import.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'response'.
+//   request.response; // error
+//           ^^^^^^^^
+//
+// pkg/front_end/testcases/dart2js/conditional_import.dart:25:11: Error: The getter 'readyState' isn't defined for the class 'HttpRequest'.
+//  - 'HttpRequest' is from 'pkg/front_end/testcases/dart2js/conditional_import.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'readyState'.
+//   request.readyState; // error
+//           ^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_http" as _ht;
+import "dart:io" as io;
+
+import "dart:io" as a;
+import "org-dartlang-testcase:///conditional_import.dart" as b;
+
+class HttpRequest extends core::Object {
+  synthetic constructor •() → self::HttpRequest
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff() → self::HttpRequest
+    return new self::HttpRequest::•();
+}
+static method testA(_ht::HttpRequest request) → dynamic {
+  request.{_ht::HttpRequest::certificate}{io::X509Certificate?};
+  request.{_ht::HttpRequest::response}{_ht::HttpResponse};
+  invalid-expression "pkg/front_end/testcases/dart2js/conditional_import.dart:18:11: Error: The getter 'readyState' isn't defined for the class 'HttpRequest'.
+ - 'HttpRequest' is from 'dart:_http'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'readyState'.
+  request.readyState; // ok (from dart:html)
+          ^^^^^^^^^^" in request{<unresolved>}.readyState;
+  request.{core::Object::hashCode}{core::int};
+}
+static method testB(self::HttpRequest request) → dynamic {
+  invalid-expression "pkg/front_end/testcases/dart2js/conditional_import.dart:23:11: Error: The getter 'certificate' isn't defined for the class 'HttpRequest'.
+ - 'HttpRequest' is from 'pkg/front_end/testcases/dart2js/conditional_import.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'certificate'.
+  request.certificate; // error
+          ^^^^^^^^^^^" in request{<unresolved>}.certificate;
+  invalid-expression "pkg/front_end/testcases/dart2js/conditional_import.dart:24:11: Error: The getter 'response' isn't defined for the class 'HttpRequest'.
+ - 'HttpRequest' is from 'pkg/front_end/testcases/dart2js/conditional_import.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'response'.
+  request.response; // error
+          ^^^^^^^^" in request{<unresolved>}.response;
+  invalid-expression "pkg/front_end/testcases/dart2js/conditional_import.dart:25:11: Error: The getter 'readyState' isn't defined for the class 'HttpRequest'.
+ - 'HttpRequest' is from 'pkg/front_end/testcases/dart2js/conditional_import.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'readyState'.
+  request.readyState; // error
+          ^^^^^^^^^^" in request{<unresolved>}.readyState;
+  request.{core::Object::hashCode}{core::int};
+}
+static method main() → void {
+  self::expect(false, #C1);
+  self::expect(true, #C1);
+  self::expect(false, #C1);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = false
+}
diff --git a/pkg/front_end/testcases/dart2js/constructor_tearoff.dart b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart
new file mode 100644
index 0000000..b7234a7
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart
@@ -0,0 +1,22 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+typedef Alias<T extends num> = Class<T>;
+
+class Class<T> {
+  Class();
+  factory Class.fact() => Class<T>();
+  factory Class.redirect() = Class<T>;
+}
+
+const a = Class.new;
+const b = Class.fact;
+const c = Class.redirect;
+const d = Alias.new;
+const e = Alias.fact;
+const f = Alias.redirect;
+
+main() {
+  print('$a$b$c$d$e$f');
+}
diff --git a/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.strong.expect b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.strong.expect
new file mode 100644
index 0000000..46e4364
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.strong.expect
@@ -0,0 +1,46 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef Alias<T extends core::num> = self::Class<T>;
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#new#tearOff::T%>
+    return new self::Class::•<self::Class::_#new#tearOff::T%>();
+  static factory fact<T extends core::Object? = dynamic>() → self::Class<self::Class::fact::T%>
+    return new self::Class::•<self::Class::fact::T%>();
+  static method _#fact#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#fact#tearOff::T%>
+    return self::Class::fact<self::Class::_#fact#tearOff::T%>();
+  static factory redirect<T extends core::Object? = dynamic>() → self::Class<self::Class::redirect::T%>
+    return new self::Class::•<self::Class::redirect::T%>();
+  static method _#redirect#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#redirect#tearOff::T%>
+    return new self::Class::•<self::Class::_#redirect#tearOff::T%>();
+}
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> a = #C2;
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> b = #C3;
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> c = #C4;
+static const field <T extends core::num>() → self::Class<T> d = #C5;
+static const field <T extends core::num>() → self::Class<T> e = #C6;
+static const field <T extends core::num>() → self::Class<T> f = #C7;
+static method main() → dynamic {
+  core::print("${#C2}${#C3}${#C4}${#C5}${#C6}${#C7}");
+}
+static method _#Alias#new#tearOff<T extends core::num>() → self::Class<self::_#Alias#new#tearOff::T>
+  return new self::Class::•<self::_#Alias#new#tearOff::T>();
+static method _#Alias#fact#tearOff<T extends core::num>() → self::Class<self::_#Alias#fact#tearOff::T>
+  return self::Class::fact<self::_#Alias#fact#tearOff::T>();
+static method _#Alias#redirect#tearOff<T extends core::num>() → self::Class<self::_#Alias#redirect#tearOff::T>
+  return self::Class::_#redirect#tearOff<self::_#Alias#redirect#tearOff::T>();
+
+constants  {
+  #C1 = constructor-tearoff self::Class::redirect
+  #C2 = static-tearoff self::Class::_#new#tearOff
+  #C3 = static-tearoff self::Class::_#fact#tearOff
+  #C4 = static-tearoff self::Class::_#redirect#tearOff
+  #C5 = static-tearoff self::_#Alias#new#tearOff
+  #C6 = static-tearoff self::_#Alias#fact#tearOff
+  #C7 = static-tearoff self::_#Alias#redirect#tearOff
+}
diff --git a/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.strong.transformed.expect b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.strong.transformed.expect
new file mode 100644
index 0000000..46e4364
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.strong.transformed.expect
@@ -0,0 +1,46 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef Alias<T extends core::num> = self::Class<T>;
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#new#tearOff::T%>
+    return new self::Class::•<self::Class::_#new#tearOff::T%>();
+  static factory fact<T extends core::Object? = dynamic>() → self::Class<self::Class::fact::T%>
+    return new self::Class::•<self::Class::fact::T%>();
+  static method _#fact#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#fact#tearOff::T%>
+    return self::Class::fact<self::Class::_#fact#tearOff::T%>();
+  static factory redirect<T extends core::Object? = dynamic>() → self::Class<self::Class::redirect::T%>
+    return new self::Class::•<self::Class::redirect::T%>();
+  static method _#redirect#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#redirect#tearOff::T%>
+    return new self::Class::•<self::Class::_#redirect#tearOff::T%>();
+}
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> a = #C2;
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> b = #C3;
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> c = #C4;
+static const field <T extends core::num>() → self::Class<T> d = #C5;
+static const field <T extends core::num>() → self::Class<T> e = #C6;
+static const field <T extends core::num>() → self::Class<T> f = #C7;
+static method main() → dynamic {
+  core::print("${#C2}${#C3}${#C4}${#C5}${#C6}${#C7}");
+}
+static method _#Alias#new#tearOff<T extends core::num>() → self::Class<self::_#Alias#new#tearOff::T>
+  return new self::Class::•<self::_#Alias#new#tearOff::T>();
+static method _#Alias#fact#tearOff<T extends core::num>() → self::Class<self::_#Alias#fact#tearOff::T>
+  return self::Class::fact<self::_#Alias#fact#tearOff::T>();
+static method _#Alias#redirect#tearOff<T extends core::num>() → self::Class<self::_#Alias#redirect#tearOff::T>
+  return self::Class::_#redirect#tearOff<self::_#Alias#redirect#tearOff::T>();
+
+constants  {
+  #C1 = constructor-tearoff self::Class::redirect
+  #C2 = static-tearoff self::Class::_#new#tearOff
+  #C3 = static-tearoff self::Class::_#fact#tearOff
+  #C4 = static-tearoff self::Class::_#redirect#tearOff
+  #C5 = static-tearoff self::_#Alias#new#tearOff
+  #C6 = static-tearoff self::_#Alias#fact#tearOff
+  #C7 = static-tearoff self::_#Alias#redirect#tearOff
+}
diff --git a/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.textual_outline.expect b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.textual_outline.expect
new file mode 100644
index 0000000..89d865d
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.textual_outline.expect
@@ -0,0 +1,15 @@
+typedef Alias<T extends num> = Class<T>;
+
+class Class<T> {
+  Class();
+  factory Class.fact() => Class<T>();
+  factory Class.redirect() = Class<T>;
+}
+
+const a = Class.new;
+const b = Class.fact;
+const c = Class.redirect;
+const d = Alias.new;
+const e = Alias.fact;
+const f = Alias.redirect;
+main() {}
diff --git a/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.textual_outline_modelled.expect b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.textual_outline_modelled.expect
new file mode 100644
index 0000000..3f714c9
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.textual_outline_modelled.expect
@@ -0,0 +1,14 @@
+class Class<T> {
+  Class();
+  factory Class.fact() => Class<T>();
+  factory Class.redirect() = Class<T>;
+}
+
+const a = Class.new;
+const b = Class.fact;
+const c = Class.redirect;
+const d = Alias.new;
+const e = Alias.fact;
+const f = Alias.redirect;
+main() {}
+typedef Alias<T extends num> = Class<T>;
diff --git a/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.weak.expect b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.weak.expect
new file mode 100644
index 0000000..46e4364
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.weak.expect
@@ -0,0 +1,46 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef Alias<T extends core::num> = self::Class<T>;
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#new#tearOff::T%>
+    return new self::Class::•<self::Class::_#new#tearOff::T%>();
+  static factory fact<T extends core::Object? = dynamic>() → self::Class<self::Class::fact::T%>
+    return new self::Class::•<self::Class::fact::T%>();
+  static method _#fact#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#fact#tearOff::T%>
+    return self::Class::fact<self::Class::_#fact#tearOff::T%>();
+  static factory redirect<T extends core::Object? = dynamic>() → self::Class<self::Class::redirect::T%>
+    return new self::Class::•<self::Class::redirect::T%>();
+  static method _#redirect#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#redirect#tearOff::T%>
+    return new self::Class::•<self::Class::_#redirect#tearOff::T%>();
+}
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> a = #C2;
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> b = #C3;
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> c = #C4;
+static const field <T extends core::num>() → self::Class<T> d = #C5;
+static const field <T extends core::num>() → self::Class<T> e = #C6;
+static const field <T extends core::num>() → self::Class<T> f = #C7;
+static method main() → dynamic {
+  core::print("${#C2}${#C3}${#C4}${#C5}${#C6}${#C7}");
+}
+static method _#Alias#new#tearOff<T extends core::num>() → self::Class<self::_#Alias#new#tearOff::T>
+  return new self::Class::•<self::_#Alias#new#tearOff::T>();
+static method _#Alias#fact#tearOff<T extends core::num>() → self::Class<self::_#Alias#fact#tearOff::T>
+  return self::Class::fact<self::_#Alias#fact#tearOff::T>();
+static method _#Alias#redirect#tearOff<T extends core::num>() → self::Class<self::_#Alias#redirect#tearOff::T>
+  return self::Class::_#redirect#tearOff<self::_#Alias#redirect#tearOff::T>();
+
+constants  {
+  #C1 = constructor-tearoff self::Class::redirect
+  #C2 = static-tearoff self::Class::_#new#tearOff
+  #C3 = static-tearoff self::Class::_#fact#tearOff
+  #C4 = static-tearoff self::Class::_#redirect#tearOff
+  #C5 = static-tearoff self::_#Alias#new#tearOff
+  #C6 = static-tearoff self::_#Alias#fact#tearOff
+  #C7 = static-tearoff self::_#Alias#redirect#tearOff
+}
diff --git a/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.weak.modular.expect
new file mode 100644
index 0000000..46e4364
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef Alias<T extends core::num> = self::Class<T>;
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#new#tearOff::T%>
+    return new self::Class::•<self::Class::_#new#tearOff::T%>();
+  static factory fact<T extends core::Object? = dynamic>() → self::Class<self::Class::fact::T%>
+    return new self::Class::•<self::Class::fact::T%>();
+  static method _#fact#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#fact#tearOff::T%>
+    return self::Class::fact<self::Class::_#fact#tearOff::T%>();
+  static factory redirect<T extends core::Object? = dynamic>() → self::Class<self::Class::redirect::T%>
+    return new self::Class::•<self::Class::redirect::T%>();
+  static method _#redirect#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#redirect#tearOff::T%>
+    return new self::Class::•<self::Class::_#redirect#tearOff::T%>();
+}
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> a = #C2;
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> b = #C3;
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> c = #C4;
+static const field <T extends core::num>() → self::Class<T> d = #C5;
+static const field <T extends core::num>() → self::Class<T> e = #C6;
+static const field <T extends core::num>() → self::Class<T> f = #C7;
+static method main() → dynamic {
+  core::print("${#C2}${#C3}${#C4}${#C5}${#C6}${#C7}");
+}
+static method _#Alias#new#tearOff<T extends core::num>() → self::Class<self::_#Alias#new#tearOff::T>
+  return new self::Class::•<self::_#Alias#new#tearOff::T>();
+static method _#Alias#fact#tearOff<T extends core::num>() → self::Class<self::_#Alias#fact#tearOff::T>
+  return self::Class::fact<self::_#Alias#fact#tearOff::T>();
+static method _#Alias#redirect#tearOff<T extends core::num>() → self::Class<self::_#Alias#redirect#tearOff::T>
+  return self::Class::_#redirect#tearOff<self::_#Alias#redirect#tearOff::T>();
+
+constants  {
+  #C1 = constructor-tearoff self::Class::redirect
+  #C2 = static-tearoff self::Class::_#new#tearOff
+  #C3 = static-tearoff self::Class::_#fact#tearOff
+  #C4 = static-tearoff self::Class::_#redirect#tearOff
+  #C5 = static-tearoff self::_#Alias#new#tearOff
+  #C6 = static-tearoff self::_#Alias#fact#tearOff
+  #C7 = static-tearoff self::_#Alias#redirect#tearOff
+}
diff --git a/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.weak.outline.expect b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.weak.outline.expect
new file mode 100644
index 0000000..48c9e36
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.weak.outline.expect
@@ -0,0 +1,45 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef Alias<T extends core::num> = self::Class<T>;
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[self::Class::redirect]/*isLegacy*/;
+  constructor •() → self::Class<self::Class::T%>
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#new#tearOff::T%>
+    return new self::Class::•<self::Class::_#new#tearOff::T%>();
+  static factory fact<T extends core::Object? = dynamic>() → self::Class<self::Class::fact::T%>
+    ;
+  static method _#fact#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#fact#tearOff::T%>
+    return self::Class::fact<self::Class::_#fact#tearOff::T%>();
+  static factory redirect<T extends core::Object? = dynamic>() → self::Class<self::Class::redirect::T%>
+    return new self::Class::•<self::Class::redirect::T%>();
+  static method _#redirect#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#redirect#tearOff::T%>
+    return new self::Class::•<self::Class::_#redirect#tearOff::T%>();
+}
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> a = self::Class::_#new#tearOff;
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> b = self::Class::_#fact#tearOff;
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> c = self::Class::_#redirect#tearOff;
+static const field <T extends core::num>() → self::Class<T> d = self::_#Alias#new#tearOff;
+static const field <T extends core::num>() → self::Class<T> e = self::_#Alias#fact#tearOff;
+static const field <T extends core::num>() → self::Class<T> f = self::_#Alias#redirect#tearOff;
+static method main() → dynamic
+  ;
+static method _#Alias#new#tearOff<T extends core::num>() → self::Class<self::_#Alias#new#tearOff::T>
+  return new self::Class::•<self::_#Alias#new#tearOff::T>();
+static method _#Alias#fact#tearOff<T extends core::num>() → self::Class<self::_#Alias#fact#tearOff::T>
+  return self::Class::fact<self::_#Alias#fact#tearOff::T>();
+static method _#Alias#redirect#tearOff<T extends core::num>() → self::Class<self::_#Alias#redirect#tearOff::T>
+  return self::Class::_#redirect#tearOff<self::_#Alias#redirect#tearOff::T>();
+
+
+Extra constant evaluation status:
+Evaluated: ConstructorTearOff @ org-dartlang-testcase:///constructor_tearoff.dart:7:7 -> ConstructorTearOffConstant(Class.redirect)
+Evaluated: StaticTearOff @ org-dartlang-testcase:///constructor_tearoff.dart:13:11 -> StaticTearOffConstant(Class._#new#tearOff)
+Evaluated: StaticTearOff @ org-dartlang-testcase:///constructor_tearoff.dart:14:11 -> StaticTearOffConstant(Class._#fact#tearOff)
+Evaluated: StaticTearOff @ org-dartlang-testcase:///constructor_tearoff.dart:15:11 -> StaticTearOffConstant(Class._#redirect#tearOff)
+Evaluated: StaticTearOff @ org-dartlang-testcase:///constructor_tearoff.dart:16:11 -> StaticTearOffConstant(_#Alias#new#tearOff)
+Evaluated: StaticTearOff @ org-dartlang-testcase:///constructor_tearoff.dart:17:11 -> StaticTearOffConstant(_#Alias#fact#tearOff)
+Evaluated: StaticTearOff @ org-dartlang-testcase:///constructor_tearoff.dart:18:11 -> StaticTearOffConstant(_#Alias#redirect#tearOff)
+Extra constant evaluation: evaluated: 15, effectively constant: 7
diff --git a/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.weak.transformed.expect b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.weak.transformed.expect
new file mode 100644
index 0000000..46e4364
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/constructor_tearoff.dart.weak.transformed.expect
@@ -0,0 +1,46 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef Alias<T extends core::num> = self::Class<T>;
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#new#tearOff::T%>
+    return new self::Class::•<self::Class::_#new#tearOff::T%>();
+  static factory fact<T extends core::Object? = dynamic>() → self::Class<self::Class::fact::T%>
+    return new self::Class::•<self::Class::fact::T%>();
+  static method _#fact#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#fact#tearOff::T%>
+    return self::Class::fact<self::Class::_#fact#tearOff::T%>();
+  static factory redirect<T extends core::Object? = dynamic>() → self::Class<self::Class::redirect::T%>
+    return new self::Class::•<self::Class::redirect::T%>();
+  static method _#redirect#tearOff<T extends core::Object? = dynamic>() → self::Class<self::Class::_#redirect#tearOff::T%>
+    return new self::Class::•<self::Class::_#redirect#tearOff::T%>();
+}
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> a = #C2;
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> b = #C3;
+static const field <T extends core::Object? = dynamic>() → self::Class<T%> c = #C4;
+static const field <T extends core::num>() → self::Class<T> d = #C5;
+static const field <T extends core::num>() → self::Class<T> e = #C6;
+static const field <T extends core::num>() → self::Class<T> f = #C7;
+static method main() → dynamic {
+  core::print("${#C2}${#C3}${#C4}${#C5}${#C6}${#C7}");
+}
+static method _#Alias#new#tearOff<T extends core::num>() → self::Class<self::_#Alias#new#tearOff::T>
+  return new self::Class::•<self::_#Alias#new#tearOff::T>();
+static method _#Alias#fact#tearOff<T extends core::num>() → self::Class<self::_#Alias#fact#tearOff::T>
+  return self::Class::fact<self::_#Alias#fact#tearOff::T>();
+static method _#Alias#redirect#tearOff<T extends core::num>() → self::Class<self::_#Alias#redirect#tearOff::T>
+  return self::Class::_#redirect#tearOff<self::_#Alias#redirect#tearOff::T>();
+
+constants  {
+  #C1 = constructor-tearoff self::Class::redirect
+  #C2 = static-tearoff self::Class::_#new#tearOff
+  #C3 = static-tearoff self::Class::_#fact#tearOff
+  #C4 = static-tearoff self::Class::_#redirect#tearOff
+  #C5 = static-tearoff self::_#Alias#new#tearOff
+  #C6 = static-tearoff self::_#Alias#fact#tearOff
+  #C7 = static-tearoff self::_#Alias#redirect#tearOff
+}
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart
new file mode 100644
index 0000000..eba0279
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart
@@ -0,0 +1,12 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'main_lib.dart';
+
+main() {
+  MyInt.a = 42;
+  print(MyInt.a);
+  MyInt.b = 87;
+  print(MyInt.b);
+}
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.strong.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.strong.expect
new file mode 100644
index 0000000..22796ec
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.strong.expect
@@ -0,0 +1,38 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart:8:9: Error: Setter not found: 'a'.
+//   MyInt.a = 42;
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+import "main_lib.dart" as mai;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart:8:9: Error: Setter not found: 'a'.
+  MyInt.a = 42;
+        ^";
+  core::print(mai::_#MyInt|a);
+  mai::MyInt|b = 87;
+  core::print(mai::MyInt|b);
+}
+
+library /*isNonNullableByDefault*/;
+import self as mai;
+import "dart:core" as core;
+import "dart:_late_helper" as _la;
+
+extension MyInt on core::int {
+  static field a = mai::_#MyInt|a;
+  static field b = mai::MyInt|b;
+}
+static final field _la::_Cell _#MyInt|a = new _la::_Cell::named("MyInt|a");
+late static field core::int MyInt|b = 42;
+static get MyInt|a() → core::int
+  return mai::_#MyInt|a.{_la::_Cell::readField}<core::int>(){() → core::int};
+static set MyInt|a(core::int value) → void
+  return mai::_#MyInt|a.{_la::_Cell::value} = value;
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.strong.transformed.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.strong.transformed.expect
new file mode 100644
index 0000000..22796ec
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.strong.transformed.expect
@@ -0,0 +1,38 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart:8:9: Error: Setter not found: 'a'.
+//   MyInt.a = 42;
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+import "main_lib.dart" as mai;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart:8:9: Error: Setter not found: 'a'.
+  MyInt.a = 42;
+        ^";
+  core::print(mai::_#MyInt|a);
+  mai::MyInt|b = 87;
+  core::print(mai::MyInt|b);
+}
+
+library /*isNonNullableByDefault*/;
+import self as mai;
+import "dart:core" as core;
+import "dart:_late_helper" as _la;
+
+extension MyInt on core::int {
+  static field a = mai::_#MyInt|a;
+  static field b = mai::MyInt|b;
+}
+static final field _la::_Cell _#MyInt|a = new _la::_Cell::named("MyInt|a");
+late static field core::int MyInt|b = 42;
+static get MyInt|a() → core::int
+  return mai::_#MyInt|a.{_la::_Cell::readField}<core::int>(){() → core::int};
+static set MyInt|a(core::int value) → void
+  return mai::_#MyInt|a.{_la::_Cell::value} = value;
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.textual_outline.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.textual_outline.expect
new file mode 100644
index 0000000..82be6bb
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.textual_outline.expect
@@ -0,0 +1,3 @@
+import 'main_lib.dart';
+
+main() {}
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.textual_outline_modelled.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.textual_outline_modelled.expect
new file mode 100644
index 0000000..82be6bb
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.textual_outline_modelled.expect
@@ -0,0 +1,3 @@
+import 'main_lib.dart';
+
+main() {}
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.weak.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.weak.expect
new file mode 100644
index 0000000..22796ec
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.weak.expect
@@ -0,0 +1,38 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart:8:9: Error: Setter not found: 'a'.
+//   MyInt.a = 42;
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+import "main_lib.dart" as mai;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart:8:9: Error: Setter not found: 'a'.
+  MyInt.a = 42;
+        ^";
+  core::print(mai::_#MyInt|a);
+  mai::MyInt|b = 87;
+  core::print(mai::MyInt|b);
+}
+
+library /*isNonNullableByDefault*/;
+import self as mai;
+import "dart:core" as core;
+import "dart:_late_helper" as _la;
+
+extension MyInt on core::int {
+  static field a = mai::_#MyInt|a;
+  static field b = mai::MyInt|b;
+}
+static final field _la::_Cell _#MyInt|a = new _la::_Cell::named("MyInt|a");
+late static field core::int MyInt|b = 42;
+static get MyInt|a() → core::int
+  return mai::_#MyInt|a.{_la::_Cell::readField}<core::int>(){() → core::int};
+static set MyInt|a(core::int value) → void
+  return mai::_#MyInt|a.{_la::_Cell::value} = value;
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.weak.modular.expect
new file mode 100644
index 0000000..e99296f
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart:8:9: Error: Setter not found: 'a'.
+//   MyInt.a = 42;
+//         ^
+//
+// pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart:10:9: Error: Setter not found: 'b'.
+//   MyInt.b = 87;
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+import "main_lib.dart" as mai;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart:8:9: Error: Setter not found: 'a'.
+  MyInt.a = 42;
+        ^";
+  core::print(mai::_#MyInt|a);
+  invalid-expression "pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart:10:9: Error: Setter not found: 'b'.
+  MyInt.b = 87;
+        ^";
+  core::print(mai::_#MyInt|b);
+}
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.weak.outline.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.weak.outline.expect
new file mode 100644
index 0000000..0d8e400
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.weak.outline.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+static method main() → dynamic
+  ;
+
+library /*isNonNullableByDefault*/;
+import self as self2;
+import "dart:core" as core;
+import "dart:_late_helper" as _la;
+
+extension MyInt on core::int {
+  static field a = self2::_#MyInt|a;
+  static field b = self2::_#MyInt|b;
+}
+static final field _la::_Cell _#MyInt|a = new _la::_Cell::named("MyInt|a");
+static final field _la::_Cell _#MyInt|b = new _la::_Cell::named("MyInt|b");
+static get MyInt|a() → core::int
+  return self2::_#MyInt|a.{_la::_Cell::readField}<core::int>(){() → core::int};
+static set MyInt|a(core::int value) → void
+  return self2::_#MyInt|a.{_la::_Cell::value} = value;
+static get MyInt|b() → core::int
+  return self2::_#MyInt|b.{_la::_Cell::readField}<core::int>(){() → core::int};
+static set MyInt|b(core::int value) → void
+  return self2::_#MyInt|b.{_la::_Cell::value} = value;
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.weak.transformed.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.weak.transformed.expect
new file mode 100644
index 0000000..22796ec
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart.weak.transformed.expect
@@ -0,0 +1,38 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart:8:9: Error: Setter not found: 'a'.
+//   MyInt.a = 42;
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+import "main_lib.dart" as mai;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/dart2js/flutter_issue94561/main.dart:8:9: Error: Setter not found: 'a'.
+  MyInt.a = 42;
+        ^";
+  core::print(mai::_#MyInt|a);
+  mai::MyInt|b = 87;
+  core::print(mai::MyInt|b);
+}
+
+library /*isNonNullableByDefault*/;
+import self as mai;
+import "dart:core" as core;
+import "dart:_late_helper" as _la;
+
+extension MyInt on core::int {
+  static field a = mai::_#MyInt|a;
+  static field b = mai::MyInt|b;
+}
+static final field _la::_Cell _#MyInt|a = new _la::_Cell::named("MyInt|a");
+late static field core::int MyInt|b = 42;
+static get MyInt|a() → core::int
+  return mai::_#MyInt|a.{_la::_Cell::readField}<core::int>(){() → core::int};
+static set MyInt|a(core::int value) → void
+  return mai::_#MyInt|a.{_la::_Cell::value} = value;
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart
new file mode 100644
index 0000000..eba0279
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart
@@ -0,0 +1,12 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'main_lib.dart';
+
+main() {
+  MyInt.a = 42;
+  print(MyInt.a);
+  MyInt.b = 87;
+  print(MyInt.b);
+}
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.strong.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.strong.expect
new file mode 100644
index 0000000..212c4ea
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.strong.expect
@@ -0,0 +1,24 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "main_lib.dart" as mai;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+static method main() → dynamic {
+  mai::MyInt|a = 42;
+  core::print(mai::MyInt|a);
+  mai::MyInt|b = 87;
+  core::print(mai::MyInt|b);
+}
+
+library /*isNonNullableByDefault*/;
+import self as mai;
+import "dart:core" as core;
+
+extension MyInt on core::int {
+  static field a = mai::MyInt|a;
+  static field b = mai::MyInt|b;
+}
+late static field core::int MyInt|a;
+late static field core::int MyInt|b = 42;
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.strong.transformed.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.strong.transformed.expect
new file mode 100644
index 0000000..c8646b7
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.strong.transformed.expect
@@ -0,0 +1,29 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "main_lib.dart" as mai;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+static method main() → dynamic {
+  mai::MyInt|a = 42;
+  core::print(mai::MyInt|a);
+  mai::MyInt|b = 87;
+  core::print(mai::MyInt|b);
+}
+
+library /*isNonNullableByDefault*/;
+import self as mai;
+import "dart:core" as core;
+import "dart:_late_helper" as _la;
+
+extension MyInt on core::int {
+  static field a = mai::_#MyInt|a;
+  static field b = mai::MyInt|b;
+}
+static final field _la::_Cell _#MyInt|a = new _la::_Cell::named("MyInt|a");
+late static field core::int MyInt|b = 42;
+static get MyInt|a() → core::int
+  return mai::_#MyInt|a.{_la::_Cell::readField}<core::int>(){() → core::int};
+static set MyInt|a(core::int value) → void
+  return mai::_#MyInt|a.{_la::_Cell::value} = value;
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.textual_outline.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.textual_outline.expect
new file mode 100644
index 0000000..82be6bb
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.textual_outline.expect
@@ -0,0 +1,3 @@
+import 'main_lib.dart';
+
+main() {}
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.textual_outline_modelled.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.textual_outline_modelled.expect
new file mode 100644
index 0000000..82be6bb
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.textual_outline_modelled.expect
@@ -0,0 +1,3 @@
+import 'main_lib.dart';
+
+main() {}
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.weak.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.weak.expect
new file mode 100644
index 0000000..212c4ea
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.weak.expect
@@ -0,0 +1,24 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "main_lib.dart" as mai;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+static method main() → dynamic {
+  mai::MyInt|a = 42;
+  core::print(mai::MyInt|a);
+  mai::MyInt|b = 87;
+  core::print(mai::MyInt|b);
+}
+
+library /*isNonNullableByDefault*/;
+import self as mai;
+import "dart:core" as core;
+
+extension MyInt on core::int {
+  static field a = mai::MyInt|a;
+  static field b = mai::MyInt|b;
+}
+late static field core::int MyInt|a;
+late static field core::int MyInt|b = 42;
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.weak.modular.expect
new file mode 100644
index 0000000..212c4ea
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "main_lib.dart" as mai;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+static method main() → dynamic {
+  mai::MyInt|a = 42;
+  core::print(mai::MyInt|a);
+  mai::MyInt|b = 87;
+  core::print(mai::MyInt|b);
+}
+
+library /*isNonNullableByDefault*/;
+import self as mai;
+import "dart:core" as core;
+
+extension MyInt on core::int {
+  static field a = mai::MyInt|a;
+  static field b = mai::MyInt|b;
+}
+late static field core::int MyInt|a;
+late static field core::int MyInt|b = 42;
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.weak.outline.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.weak.outline.expect
new file mode 100644
index 0000000..5451823
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.weak.outline.expect
@@ -0,0 +1,18 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+static method main() → dynamic
+  ;
+
+library /*isNonNullableByDefault*/;
+import self as self2;
+import "dart:core" as core;
+
+extension MyInt on core::int {
+  static field a = self2::MyInt|a;
+  static field b = self2::MyInt|b;
+}
+late static field core::int MyInt|a;
+late static field core::int MyInt|b;
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.weak.transformed.expect b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.weak.transformed.expect
new file mode 100644
index 0000000..c8646b7
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main.no_link.dart.weak.transformed.expect
@@ -0,0 +1,29 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "main_lib.dart" as mai;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+static method main() → dynamic {
+  mai::MyInt|a = 42;
+  core::print(mai::MyInt|a);
+  mai::MyInt|b = 87;
+  core::print(mai::MyInt|b);
+}
+
+library /*isNonNullableByDefault*/;
+import self as mai;
+import "dart:core" as core;
+import "dart:_late_helper" as _la;
+
+extension MyInt on core::int {
+  static field a = mai::_#MyInt|a;
+  static field b = mai::MyInt|b;
+}
+static final field _la::_Cell _#MyInt|a = new _la::_Cell::named("MyInt|a");
+late static field core::int MyInt|b = 42;
+static get MyInt|a() → core::int
+  return mai::_#MyInt|a.{_la::_Cell::readField}<core::int>(){() → core::int};
+static set MyInt|a(core::int value) → void
+  return mai::_#MyInt|a.{_la::_Cell::value} = value;
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/main_lib.dart b/pkg/front_end/testcases/dart2js/flutter_issue94561/main_lib.dart
new file mode 100644
index 0000000..7fcb8f2
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/main_lib.dart
@@ -0,0 +1,8 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+extension MyInt on int {
+  static late int a;
+  static late int b = 42;
+}
diff --git a/pkg/front_end/testcases/dart2js/flutter_issue94561/test.options b/pkg/front_end/testcases/dart2js/flutter_issue94561/test.options
new file mode 100644
index 0000000..61731a9
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/flutter_issue94561/test.options
@@ -0,0 +1 @@
+main_lib.dart
diff --git a/pkg/front_end/testcases/dart2js/instance_getter_invocation.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/instance_getter_invocation.dart.weak.modular.expect
new file mode 100644
index 0000000..d249938
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/instance_getter_invocation.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  get idFunction() → <S extends core::Object? = dynamic>(S%) → S%
+    return #C1;
+  get dynFunction() → dynamic
+    return #C1;
+  static method _#new#tearOff() → self::Class
+    return new self::Class::•();
+}
+static method id<T extends core::Object? = dynamic>(self::id::T% t) → self::id::T%
+  return t;
+static method main() → dynamic {
+  self::Class c = new self::Class::•();
+  let final self::Class #t1 = c in let final core::int #t2 = 0 in #t1.{self::Class::idFunction}<core::int>(#t2){(core::int) → core::int};
+  let final self::Class #t3 = c in let final core::int #t4 = 0 in #t3.{self::Class::idFunction}<core::int>(#t4){(core::int) → core::int};
+  let final self::Class #t5 = c in let final core::int #t6 = 0 in #t5.{self::Class::dynFunction}(#t6);
+}
+
+constants  {
+  #C1 = static-tearoff self::id
+}
diff --git a/pkg/front_end/testcases/dart2js/late_fields.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/late_fields.dart.weak.modular.expect
new file mode 100644
index 0000000..a546427
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/late_fields.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  late field core::int a;
+  late final [setter] field core::int b;
+  late field core::int c = 1.{core::int::unary-}(){() → core::int};
+  late final field core::int d = 1.{core::int::unary-}(){() → core::int};
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff() → self::C
+    return new self::C::•();
+}
+static field self::C c = new self::C::•();
+static method main() → void {
+  self::testUninitializedNonFinalInstanceField();
+  self::testUninitializedFinalInstanceField();
+  self::testInitializedNonFinalInstanceField();
+  self::testInitializedFinalInstanceField();
+}
+static method testUninitializedNonFinalInstanceField() → void {
+  core::print(self::c.{self::C::a}{core::int});
+  self::c.{self::C::a} = 42;
+  core::print(self::c.{self::C::a}{core::int});
+}
+static method testUninitializedFinalInstanceField() → void {
+  core::print(self::c.{self::C::b}{core::int});
+  self::c.{self::C::b} = 42;
+  core::print(self::c.{self::C::b}{core::int});
+}
+static method testInitializedNonFinalInstanceField() → void {
+  core::print(self::c.{self::C::c}{core::int});
+  self::c.{self::C::c} = 42;
+  core::print(self::c.{self::C::c}{core::int});
+}
+static method testInitializedFinalInstanceField() → void {
+  core::print(self::c.{self::C::d}{core::int});
+}
diff --git a/pkg/front_end/testcases/dart2js/late_from_dill/main.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/late_from_dill/main.dart.weak.modular.expect
new file mode 100644
index 0000000..ece489e
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/late_from_dill/main.dart.weak.modular.expect
@@ -0,0 +1,86 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "main_lib1.dart" as mai;
+import "dart:core" as core;
+import "main_lib2.dart" as mai2;
+
+import "org-dartlang-testcase:///main_lib1.dart";
+import "org-dartlang-testcase:///main_lib2.dart" as lib;
+
+static field mai::C c = new mai::C::•();
+static method main() → void {
+  self::testUninitializedNonFinalInstanceField();
+  self::testUninitializedFinalInstanceField();
+  self::testInitializedNonFinalInstanceField();
+  self::testInitializedFinalInstanceField();
+  mai::testNullableUninitializedNonFinalLocal();
+  mai::testNonNullableUninitializedNonFinalLocal();
+  mai::testNullableUninitializedFinalLocal();
+  mai::testNonNullableUninitializedFinalLocal();
+  mai::testNullableInitializedNonFinalLocal();
+  mai::testNonNullableInitializedNonFinalLocal();
+  mai::testNullableInitializedFinalLocal();
+  mai::testNonNullableInitializedFinalLocal();
+  self::testUninitializedNonFinalStaticField();
+  self::testUninitializedFinalStaticField();
+  self::testInitializedNonFinalStaticField();
+  self::testInitializedFinalStaticField();
+  self::testUninitializedNonFinalTopLevelField();
+  self::testUninitializedFinalTopLevelField();
+  self::testInitializedNonFinalTopLevelField();
+  self::testInitializedFinalTopLevelField();
+}
+static method testUninitializedNonFinalInstanceField() → void {
+  core::print(self::c.{mai::C::a}{core::int});
+  self::c.{mai::C::a} = 42;
+  core::print(self::c.{mai::C::a}{core::int});
+}
+static method testUninitializedFinalInstanceField() → void {
+  core::print(self::c.{mai::C::b}{core::int});
+  self::c.{mai::C::b} = 42;
+  core::print(self::c.{mai::C::b}{core::int});
+}
+static method testInitializedNonFinalInstanceField() → void {
+  core::print(self::c.{mai::C::c}{core::int});
+  self::c.{mai::C::c} = 42;
+  core::print(self::c.{mai::C::c}{core::int});
+}
+static method testInitializedFinalInstanceField() → void {
+  core::print(self::c.{mai::C::d}{core::int});
+}
+static method testUninitializedNonFinalStaticField() → void {
+  core::print(mai::Statics::a);
+  mai::Statics::a = 42;
+  core::print(mai::Statics::a);
+}
+static method testUninitializedFinalStaticField() → void {
+  core::print(mai::Statics::b);
+  mai::Statics::b = 42;
+  core::print(mai::Statics::b);
+}
+static method testInitializedNonFinalStaticField() → void {
+  core::print(mai::Statics::c);
+  mai::Statics::c = 42;
+  core::print(mai::Statics::c);
+}
+static method testInitializedFinalStaticField() → void {
+  core::print(mai::Statics::d);
+}
+static method testUninitializedNonFinalTopLevelField() → void {
+  core::print(mai2::a);
+  mai2::a = 42;
+  core::print(mai2::a);
+}
+static method testUninitializedFinalTopLevelField() → void {
+  core::print(mai2::b);
+  mai2::b = 42;
+  core::print(mai2::b);
+}
+static method testInitializedNonFinalTopLevelField() → void {
+  core::print(mai2::c);
+  mai2::c = 42;
+  core::print(mai2::c);
+}
+static method testInitializedFinalTopLevelField() → void {
+  core::print(mai2::d);
+}
diff --git a/pkg/front_end/testcases/dart2js/late_locals.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/late_locals.dart.weak.modular.expect
new file mode 100644
index 0000000..0ecd84b
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/late_locals.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method main() → void {
+  self::testNullableUninitializedNonFinalLocal();
+  self::testNonNullableUninitializedNonFinalLocal();
+  self::testNullableUninitializedFinalLocal();
+  self::testNonNullableUninitializedFinalLocal();
+  self::testNullableInitializedNonFinalLocal();
+  self::testNonNullableInitializedNonFinalLocal();
+  self::testNullableInitializedFinalLocal();
+  self::testNonNullableInitializedFinalLocal();
+}
+static method testNullableUninitializedNonFinalLocal() → void {
+  late core::int? x;
+  x = 42;
+  core::print(x{core::int});
+}
+static method testNonNullableUninitializedNonFinalLocal() → void {
+  late core::int x;
+  x = 42;
+  core::print(x);
+}
+static method testNullableUninitializedFinalLocal() → void {
+  late final core::int? x;
+  x = 42;
+  core::print(x{core::int});
+}
+static method testNonNullableUninitializedFinalLocal() → void {
+  late final core::int x;
+  x = 42;
+  core::print(x);
+}
+static method testNullableInitializedNonFinalLocal() → void {
+  late core::int? x = 1.{core::int::unary-}(){() → core::int};
+  core::print(x{core::int});
+  x = 42;
+  core::print(x{core::int});
+  late core::int? y = null;
+  core::print(y);
+  y = 42;
+  core::print(y{core::int});
+}
+static method testNonNullableInitializedNonFinalLocal() → void {
+  late core::int x = 1.{core::int::unary-}(){() → core::int};
+  core::print(x);
+  x = 42;
+  core::print(x);
+}
+static method testNullableInitializedFinalLocal() → void {
+  late final core::int? x = 1.{core::int::unary-}(){() → core::int};
+  core::print(x);
+  late final core::int? y = null;
+  core::print(y);
+}
+static method testNonNullableInitializedFinalLocal() → void {
+  late final core::int x = 1.{core::int::unary-}(){() → core::int};
+  core::print(x);
+}
diff --git a/pkg/front_end/testcases/dart2js/late_statics.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/late_statics.dart.weak.modular.expect
new file mode 100644
index 0000000..c2128f7
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/late_statics.dart.weak.modular.expect
@@ -0,0 +1,81 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "late_statics_lib.dart" as lat;
+additionalExports = (lat::a,
+  lat::a,
+  lat::b,
+  lat::b,
+  lat::c,
+  lat::c,
+  lat::d)
+
+import "org-dartlang-testcase:///late_statics_lib.dart" as lib;
+export "org-dartlang-testcase:///late_statics_lib.dart";
+
+class Statics extends core::Object {
+  late static field core::int a;
+  late static final [setter] field core::int b;
+  late static field core::int c = 1.{core::int::unary-}(){() → core::int};
+  late static final field core::int d = 1.{core::int::unary-}(){() → core::int};
+  synthetic constructor •() → self::Statics
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff() → self::Statics
+    return new self::Statics::•();
+}
+static method main() → void {
+  self::testUninitializedNonFinalStaticField();
+  self::testUninitializedFinalStaticField();
+  self::testInitializedNonFinalStaticField();
+  self::testInitializedFinalStaticField();
+  self::testUninitializedNonFinalTopLevelField();
+  self::testUninitializedFinalTopLevelField();
+  self::testInitializedNonFinalTopLevelField();
+  self::testInitializedFinalTopLevelField();
+}
+static method testUninitializedNonFinalStaticField() → void {
+  core::print(self::Statics::a);
+  self::Statics::a = 42;
+  core::print(self::Statics::a);
+}
+static method testUninitializedFinalStaticField() → void {
+  core::print(self::Statics::b);
+  self::Statics::b = 42;
+  core::print(self::Statics::b);
+}
+static method testInitializedNonFinalStaticField() → void {
+  core::print(self::Statics::c);
+  self::Statics::c = 42;
+  core::print(self::Statics::c);
+}
+static method testInitializedFinalStaticField() → void {
+  core::print(self::Statics::d);
+}
+static method testUninitializedNonFinalTopLevelField() → void {
+  core::print(lat::a);
+  lat::a = 42;
+  core::print(lat::a);
+}
+static method testUninitializedFinalTopLevelField() → void {
+  core::print(lat::b);
+  lat::b = 42;
+  core::print(lat::b);
+}
+static method testInitializedNonFinalTopLevelField() → void {
+  core::print(lat::c);
+  lat::c = 42;
+  core::print(lat::c);
+}
+static method testInitializedFinalTopLevelField() → void {
+  core::print(lat::d);
+}
+
+library /*isNonNullableByDefault*/;
+import self as lat;
+import "dart:core" as core;
+
+late static field core::int a;
+late static final [setter] field core::int b;
+late static field core::int c = 1.{core::int::unary-}(){() → core::int};
+late static final field core::int d = 1.{core::int::unary-}(){() → core::int};
diff --git a/pkg/front_end/testcases/dart2js/list_generate.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/list_generate.dart.weak.modular.expect
new file mode 100644
index 0000000..1d7d6ef
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/list_generate.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::List::generate<core::int>(10, (core::int i) → core::int => i.{core::num::*}(2){(core::num) → core::int});
+}
diff --git a/pkg/front_end/testcases/dart2js/list_generate_1.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/list_generate_1.dart.weak.modular.expect
new file mode 100644
index 0000000..ae26523
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/list_generate_1.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<core::int> list1 = core::List::generate<core::int>(10, (core::int i) → core::int => i);
+static field core::List<core::int> list2 = core::List::generate<core::int>(10, (core::int i) → core::int => i, growable: true);
+static field core::List<core::int> list3 = core::List::generate<core::int>(10, (core::int i) → core::int => i, growable: false);
+static field core::List<core::int> list4 = core::List::generate<core::int>(10, (core::int i) → core::int => i, growable: self::someGrowable);
+static field core::bool someGrowable = true;
+static method main() → void {
+  self::someGrowable = !self::someGrowable;
+  core::print(<core::List<core::int>>[self::list1, self::list2, self::list3, self::list4]);
+}
diff --git a/pkg/front_end/testcases/dart2js/list_generate_2.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/list_generate_2.dart.weak.modular.expect
new file mode 100644
index 0000000..d3c85ea
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/list_generate_2.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method main() → void {
+  core::print(core::List::generate<core::List<core::int>>(10, (core::int i) → core::List<core::int> => core::List::generate<core::int>(i, (core::int i) → core::int => i.{core::num::+}(1){(core::num) → core::int})));
+}
diff --git a/pkg/front_end/testcases/dart2js/list_generate_3.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/list_generate_3.dart.weak.modular.expect
new file mode 100644
index 0000000..4f4c5d2
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/list_generate_3.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<core::int> list1 = core::List::generate<core::int>(10, (core::int i) → core::int {
+  return i;
+});
+static field core::List<core::int> list2 = core::List::generate<core::int>(10, (core::int i) → core::int {
+  return i;
+}, growable: true);
+static field core::List<core::int> list3 = core::List::generate<core::int>(10, (core::int i) → core::int {
+  return i;
+}, growable: false);
+static field core::List<core::int> list4 = core::List::generate<core::int>(10, (core::int i) → core::int {
+  return i;
+}, growable: self::someGrowable);
+static field core::List<core::int> list5 = core::List::generate<core::int>(10, (core::int i) → core::int {
+  if(i.{core::int::isEven}{core::bool})
+    return i.{core::num::+}(1){(core::num) → core::int};
+  return i.{core::num::-}(1){(core::num) → core::int};
+});
+static field core::List<core::int> list6 = core::List::generate<core::int>(10, #C1);
+static field core::List<core::int> list7 = core::List::generate<core::int>(10, self::bar);
+static field core::bool someGrowable = true;
+static method foo(core::int i) → core::int
+  return i;
+static get bar() → (core::int) → core::int
+  return #C1;
+static method main() → void {
+  self::someGrowable = !self::someGrowable;
+  core::print(<core::List<core::int>>[self::list1, self::list2, self::list3, self::list4, self::list5, self::list6, self::list7]);
+}
+
+constants  {
+  #C1 = static-tearoff self::foo
+}
diff --git a/pkg/front_end/testcases/dart2js/list_generate_local_function_invocation.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/list_generate_local_function_invocation.dart.weak.modular.expect
new file mode 100644
index 0000000..fa4652c
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/list_generate_local_function_invocation.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  function localFunction(core::int i) → core::int
+    return i.{core::num::*}(2){(core::num) → core::int};
+  core::List::generate<core::int>(10, (core::int i) → core::int => localFunction(i){(core::int) → core::int});
+}
diff --git a/pkg/front_end/testcases/dart2js/mixin_default_values/a_lib.dart b/pkg/front_end/testcases/dart2js/mixin_default_values/a_lib.dart
new file mode 100644
index 0000000..75c5e41
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_default_values/a_lib.dart
@@ -0,0 +1,21 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+import 't_lib.dart';
+
+String _defaultStringy(String t) => t.toLowerCase();
+
+class A {
+  A({
+    double d = 3.14,
+    StringyFunction<String> s = _defaultStringy,
+  }) : this.factoryConstructor(d: d, s: s);
+  A.factoryConstructor({
+    double d = 3.14,
+    StringyFunction<String> s = _defaultStringy,
+  })  : d = d,
+        _s = s;
+  String doStringy(String i) => _s(i);
+  final double d;
+  final StringyFunction<String> _s;
+}
diff --git a/pkg/front_end/testcases/dart2js/mixin_default_values/b_lib.dart b/pkg/front_end/testcases/dart2js/mixin_default_values/b_lib.dart
new file mode 100644
index 0000000..2e956fb
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_default_values/b_lib.dart
@@ -0,0 +1,10 @@
+// Copyright (c) 2020, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'a_lib.dart';
+import 'm_lib.dart';
+
+class B extends A with M {
+  B({double d = 2.71}) : super(d: d);
+}
diff --git a/pkg/front_end/testcases/dart2js/mixin_default_values/m_lib.dart b/pkg/front_end/testcases/dart2js/mixin_default_values/m_lib.dart
new file mode 100644
index 0000000..8ade71f
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_default_values/m_lib.dart
@@ -0,0 +1,9 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'a_lib.dart';
+
+mixin M on A {
+  m1() {}
+}
diff --git a/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart
new file mode 100644
index 0000000..5f99d3e
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart
@@ -0,0 +1,15 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'b_lib.dart';
+
+main() {
+  var bInst = B();
+  expect(2.71, bInst.d);
+  expect('default', bInst.doStringy('DEFAULT'));
+}
+
+expect(expected, actual) {
+  if (expected != actual) throw 'Expected $expected, actual $actual.';
+}
diff --git a/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.strong.expect b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.strong.expect
new file mode 100644
index 0000000..e58f841
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.strong.expect
@@ -0,0 +1,91 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "b_lib.dart" as b_l;
+import "a_lib.dart" as a_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///b_lib.dart";
+
+static method main() → dynamic {
+  b_l::B bInst = new b_l::B::•();
+  self::expect(2.71, bInst.{a_l::A::d}{core::double});
+  self::expect("default", bInst.{a_l::A::doStringy}("DEFAULT"){(core::String) → core::String});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}.";
+}
+
+library /*isNonNullableByDefault*/;
+import self as b_l;
+import "a_lib.dart" as a_l;
+import "m_lib.dart" as m_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///a_lib.dart";
+import "org-dartlang-testcase:///m_lib.dart";
+
+abstract class _B&A&M = a_l::A with m_l::M /*isAnonymousMixin*/  {
+  synthetic constructor •({core::double d = #C1, (core::String) → core::String s = #C2}) → b_l::_B&A&M
+    : super a_l::A::•(d: d, s: s)
+    ;
+  synthetic constructor factoryConstructor({core::double d = #C1, (core::String) → core::String s = #C2}) → b_l::_B&A&M
+    : super a_l::A::factoryConstructor(d: d, s: s)
+    ;
+  mixin-super-stub method m1() → dynamic
+    return super.{m_l::M::m1}();
+}
+class B extends b_l::_B&A&M {
+  constructor •({core::double d = #C3}) → b_l::B
+    : super b_l::_B&A&M::•(d: d)
+    ;
+  static method _#new#tearOff({core::double d = #C3}) → b_l::B
+    return new b_l::B::•(d: d);
+}
+
+library /*isNonNullableByDefault*/;
+import self as m_l;
+import "a_lib.dart" as a_l;
+
+import "org-dartlang-testcase:///a_lib.dart";
+
+abstract class M extends a_l::A /*isMixinDeclaration*/  {
+  method m1() → dynamic {}
+}
+
+library /*isNonNullableByDefault*/;
+import self as a_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///t_lib.dart";
+
+class A extends core::Object {
+  final field core::double d;
+  final field (core::String) → core::String _s;
+  constructor •({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    : this a_l::A::factoryConstructor(d: d, s: s)
+    ;
+  constructor factoryConstructor({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    : a_l::A::d = d, a_l::A::_s = s, super core::Object::•()
+    ;
+  static method _#new#tearOff({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    return new a_l::A::•(d: d, s: s);
+  static method _#factoryConstructor#tearOff({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    return new a_l::A::factoryConstructor(d: d, s: s);
+  method doStringy(core::String i) → core::String
+    return let final core::String #t1 = i in this.{a_l::A::_s}(#t1){(core::String) → core::String};
+}
+static method _defaultStringy(core::String t) → core::String
+  return t.{core::String::toLowerCase}(){() → core::String};
+
+library /*isNonNullableByDefault*/;
+import self as self2;
+import "dart:core" as core;
+
+typedef StringyFunction<contravariant T extends core::Object? = dynamic> = (T%) → core::String;
+
+constants  {
+  #C1 = 3.14
+  #C2 = static-tearoff a_l::_defaultStringy
+  #C3 = 2.71
+}
diff --git a/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.strong.transformed.expect b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.strong.transformed.expect
new file mode 100644
index 0000000..e58f841
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.strong.transformed.expect
@@ -0,0 +1,91 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "b_lib.dart" as b_l;
+import "a_lib.dart" as a_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///b_lib.dart";
+
+static method main() → dynamic {
+  b_l::B bInst = new b_l::B::•();
+  self::expect(2.71, bInst.{a_l::A::d}{core::double});
+  self::expect("default", bInst.{a_l::A::doStringy}("DEFAULT"){(core::String) → core::String});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}.";
+}
+
+library /*isNonNullableByDefault*/;
+import self as b_l;
+import "a_lib.dart" as a_l;
+import "m_lib.dart" as m_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///a_lib.dart";
+import "org-dartlang-testcase:///m_lib.dart";
+
+abstract class _B&A&M = a_l::A with m_l::M /*isAnonymousMixin*/  {
+  synthetic constructor •({core::double d = #C1, (core::String) → core::String s = #C2}) → b_l::_B&A&M
+    : super a_l::A::•(d: d, s: s)
+    ;
+  synthetic constructor factoryConstructor({core::double d = #C1, (core::String) → core::String s = #C2}) → b_l::_B&A&M
+    : super a_l::A::factoryConstructor(d: d, s: s)
+    ;
+  mixin-super-stub method m1() → dynamic
+    return super.{m_l::M::m1}();
+}
+class B extends b_l::_B&A&M {
+  constructor •({core::double d = #C3}) → b_l::B
+    : super b_l::_B&A&M::•(d: d)
+    ;
+  static method _#new#tearOff({core::double d = #C3}) → b_l::B
+    return new b_l::B::•(d: d);
+}
+
+library /*isNonNullableByDefault*/;
+import self as m_l;
+import "a_lib.dart" as a_l;
+
+import "org-dartlang-testcase:///a_lib.dart";
+
+abstract class M extends a_l::A /*isMixinDeclaration*/  {
+  method m1() → dynamic {}
+}
+
+library /*isNonNullableByDefault*/;
+import self as a_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///t_lib.dart";
+
+class A extends core::Object {
+  final field core::double d;
+  final field (core::String) → core::String _s;
+  constructor •({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    : this a_l::A::factoryConstructor(d: d, s: s)
+    ;
+  constructor factoryConstructor({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    : a_l::A::d = d, a_l::A::_s = s, super core::Object::•()
+    ;
+  static method _#new#tearOff({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    return new a_l::A::•(d: d, s: s);
+  static method _#factoryConstructor#tearOff({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    return new a_l::A::factoryConstructor(d: d, s: s);
+  method doStringy(core::String i) → core::String
+    return let final core::String #t1 = i in this.{a_l::A::_s}(#t1){(core::String) → core::String};
+}
+static method _defaultStringy(core::String t) → core::String
+  return t.{core::String::toLowerCase}(){() → core::String};
+
+library /*isNonNullableByDefault*/;
+import self as self2;
+import "dart:core" as core;
+
+typedef StringyFunction<contravariant T extends core::Object? = dynamic> = (T%) → core::String;
+
+constants  {
+  #C1 = 3.14
+  #C2 = static-tearoff a_l::_defaultStringy
+  #C3 = 2.71
+}
diff --git a/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.textual_outline.expect b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.textual_outline.expect
new file mode 100644
index 0000000..0833ebd
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.textual_outline.expect
@@ -0,0 +1,4 @@
+import 'b_lib.dart';
+
+main() {}
+expect(expected, actual) {}
diff --git a/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.textual_outline_modelled.expect b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.textual_outline_modelled.expect
new file mode 100644
index 0000000..029cb69
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.textual_outline_modelled.expect
@@ -0,0 +1,4 @@
+import 'b_lib.dart';
+
+expect(expected, actual) {}
+main() {}
diff --git a/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.weak.expect b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.weak.expect
new file mode 100644
index 0000000..e58f841
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.weak.expect
@@ -0,0 +1,91 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "b_lib.dart" as b_l;
+import "a_lib.dart" as a_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///b_lib.dart";
+
+static method main() → dynamic {
+  b_l::B bInst = new b_l::B::•();
+  self::expect(2.71, bInst.{a_l::A::d}{core::double});
+  self::expect("default", bInst.{a_l::A::doStringy}("DEFAULT"){(core::String) → core::String});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}.";
+}
+
+library /*isNonNullableByDefault*/;
+import self as b_l;
+import "a_lib.dart" as a_l;
+import "m_lib.dart" as m_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///a_lib.dart";
+import "org-dartlang-testcase:///m_lib.dart";
+
+abstract class _B&A&M = a_l::A with m_l::M /*isAnonymousMixin*/  {
+  synthetic constructor •({core::double d = #C1, (core::String) → core::String s = #C2}) → b_l::_B&A&M
+    : super a_l::A::•(d: d, s: s)
+    ;
+  synthetic constructor factoryConstructor({core::double d = #C1, (core::String) → core::String s = #C2}) → b_l::_B&A&M
+    : super a_l::A::factoryConstructor(d: d, s: s)
+    ;
+  mixin-super-stub method m1() → dynamic
+    return super.{m_l::M::m1}();
+}
+class B extends b_l::_B&A&M {
+  constructor •({core::double d = #C3}) → b_l::B
+    : super b_l::_B&A&M::•(d: d)
+    ;
+  static method _#new#tearOff({core::double d = #C3}) → b_l::B
+    return new b_l::B::•(d: d);
+}
+
+library /*isNonNullableByDefault*/;
+import self as m_l;
+import "a_lib.dart" as a_l;
+
+import "org-dartlang-testcase:///a_lib.dart";
+
+abstract class M extends a_l::A /*isMixinDeclaration*/  {
+  method m1() → dynamic {}
+}
+
+library /*isNonNullableByDefault*/;
+import self as a_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///t_lib.dart";
+
+class A extends core::Object {
+  final field core::double d;
+  final field (core::String) → core::String _s;
+  constructor •({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    : this a_l::A::factoryConstructor(d: d, s: s)
+    ;
+  constructor factoryConstructor({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    : a_l::A::d = d, a_l::A::_s = s, super core::Object::•()
+    ;
+  static method _#new#tearOff({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    return new a_l::A::•(d: d, s: s);
+  static method _#factoryConstructor#tearOff({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    return new a_l::A::factoryConstructor(d: d, s: s);
+  method doStringy(core::String i) → core::String
+    return let final core::String #t1 = i in this.{a_l::A::_s}(#t1){(core::String) → core::String};
+}
+static method _defaultStringy(core::String t) → core::String
+  return t.{core::String::toLowerCase}(){() → core::String};
+
+library /*isNonNullableByDefault*/;
+import self as self2;
+import "dart:core" as core;
+
+typedef StringyFunction<contravariant T extends core::Object? = dynamic> = (T%) → core::String;
+
+constants  {
+  #C1 = 3.14
+  #C2 = static-tearoff a_l::_defaultStringy
+  #C3 = 2.71
+}
diff --git a/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.weak.modular.expect
new file mode 100644
index 0000000..573e273
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "b_lib.dart" as b_l;
+import "a_lib.dart" as a_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///b_lib.dart";
+
+static method main() → dynamic {
+  b_l::B bInst = new b_l::B::•();
+  self::expect(2.71, bInst.{a_l::A::d}{core::double});
+  self::expect("default", bInst.{a_l::A::doStringy}("DEFAULT"){(core::String) → core::String});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}.";
+}
+
+library /*isNonNullableByDefault*/;
+import self as b_l;
+import "a_lib.dart" as a_l;
+import "m_lib.dart" as m_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///a_lib.dart";
+import "org-dartlang-testcase:///m_lib.dart";
+
+abstract class _B&A&M = a_l::A with m_l::M /*isAnonymousMixin*/  {
+  synthetic constructor •({core::double d = #C1, (core::String) → core::String s = #C2}) → b_l::_B&A&M
+    : super a_l::A::•(d: d, s: s)
+    ;
+  synthetic constructor factoryConstructor({core::double d = #C1, (core::String) → core::String s = #C2}) → b_l::_B&A&M
+    : super a_l::A::factoryConstructor(d: d, s: s)
+    ;
+  mixin-super-stub method m1() → dynamic
+    return super.{m_l::M::m1}();
+}
+class B extends b_l::_B&A&M {
+  constructor •({core::double d = #C3}) → b_l::B
+    : super b_l::_B&A&M::•(d: d)
+    ;
+  static method _#new#tearOff({core::double d = #C3}) → b_l::B
+    return new b_l::B::•(d: d);
+}
+
+library /*isNonNullableByDefault*/;
+import self as m_l;
+import "a_lib.dart" as a_l;
+
+import "org-dartlang-testcase:///a_lib.dart";
+
+abstract class M extends a_l::A /*isMixinDeclaration*/  {
+  method m1() → dynamic {}
+}
+
+constants  {
+  #C1 = 3.14
+  #C2 = static-tearoff a_l::_defaultStringy
+  #C3 = 2.71
+}
diff --git a/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.weak.outline.expect b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.weak.outline.expect
new file mode 100644
index 0000000..2950126
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.weak.outline.expect
@@ -0,0 +1,80 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+
+import "org-dartlang-testcase:///b_lib.dart";
+
+static method main() → dynamic
+  ;
+static method expect(dynamic expected, dynamic actual) → dynamic
+  ;
+
+library /*isNonNullableByDefault*/;
+import self as self2;
+import "a_lib.dart" as a_l;
+import "m_lib.dart" as m_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///a_lib.dart";
+import "org-dartlang-testcase:///m_lib.dart";
+
+abstract class _B&A&M = a_l::A with m_l::M /*isAnonymousMixin*/  {
+  synthetic constructor •({core::double d, (core::String) → core::String s}) → self2::_B&A&M
+    : super a_l::A::•(d: d, s: s)
+    ;
+  synthetic constructor factoryConstructor({core::double d, (core::String) → core::String s}) → self2::_B&A&M
+    : super a_l::A::factoryConstructor(d: d, s: s)
+    ;
+  mixin-super-stub method m1() → dynamic
+    return super.{m_l::M::m1}();
+}
+class B extends self2::_B&A&M {
+  constructor •({core::double d = 2.71}) → self2::B
+    ;
+  static method _#new#tearOff({core::double d}) → self2::B
+    return new self2::B::•(d: d);
+}
+
+library /*isNonNullableByDefault*/;
+import self as m_l;
+import "a_lib.dart" as a_l;
+
+import "org-dartlang-testcase:///a_lib.dart";
+
+abstract class M extends a_l::A /*isMixinDeclaration*/  {
+  method m1() → dynamic
+    ;
+}
+
+library /*isNonNullableByDefault*/;
+import self as a_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///t_lib.dart";
+
+class A extends core::Object {
+  final field core::double d;
+  final field (core::String) → core::String _s;
+  constructor •({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    ;
+  constructor factoryConstructor({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    ;
+  static method _#new#tearOff({core::double d, (core::String) → core::String s}) → a_l::A
+    return new a_l::A::•(d: d, s: s);
+  static method _#factoryConstructor#tearOff({core::double d, (core::String) → core::String s}) → a_l::A
+    return new a_l::A::factoryConstructor(d: d, s: s);
+  method doStringy(core::String i) → core::String
+    ;
+}
+static method _defaultStringy(core::String t) → core::String
+  ;
+
+library /*isNonNullableByDefault*/;
+import self as self3;
+import "dart:core" as core;
+
+typedef StringyFunction<contravariant T extends core::Object? = dynamic> = (T%) → core::String;
+
+constants  {
+  #C1 = 3.14
+  #C2 = static-tearoff a_l::_defaultStringy
+}
diff --git a/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.weak.transformed.expect b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.weak.transformed.expect
new file mode 100644
index 0000000..e58f841
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_default_values/main.dart.weak.transformed.expect
@@ -0,0 +1,91 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "b_lib.dart" as b_l;
+import "a_lib.dart" as a_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///b_lib.dart";
+
+static method main() → dynamic {
+  b_l::B bInst = new b_l::B::•();
+  self::expect(2.71, bInst.{a_l::A::d}{core::double});
+  self::expect("default", bInst.{a_l::A::doStringy}("DEFAULT"){(core::String) → core::String});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}.";
+}
+
+library /*isNonNullableByDefault*/;
+import self as b_l;
+import "a_lib.dart" as a_l;
+import "m_lib.dart" as m_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///a_lib.dart";
+import "org-dartlang-testcase:///m_lib.dart";
+
+abstract class _B&A&M = a_l::A with m_l::M /*isAnonymousMixin*/  {
+  synthetic constructor •({core::double d = #C1, (core::String) → core::String s = #C2}) → b_l::_B&A&M
+    : super a_l::A::•(d: d, s: s)
+    ;
+  synthetic constructor factoryConstructor({core::double d = #C1, (core::String) → core::String s = #C2}) → b_l::_B&A&M
+    : super a_l::A::factoryConstructor(d: d, s: s)
+    ;
+  mixin-super-stub method m1() → dynamic
+    return super.{m_l::M::m1}();
+}
+class B extends b_l::_B&A&M {
+  constructor •({core::double d = #C3}) → b_l::B
+    : super b_l::_B&A&M::•(d: d)
+    ;
+  static method _#new#tearOff({core::double d = #C3}) → b_l::B
+    return new b_l::B::•(d: d);
+}
+
+library /*isNonNullableByDefault*/;
+import self as m_l;
+import "a_lib.dart" as a_l;
+
+import "org-dartlang-testcase:///a_lib.dart";
+
+abstract class M extends a_l::A /*isMixinDeclaration*/  {
+  method m1() → dynamic {}
+}
+
+library /*isNonNullableByDefault*/;
+import self as a_l;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///t_lib.dart";
+
+class A extends core::Object {
+  final field core::double d;
+  final field (core::String) → core::String _s;
+  constructor •({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    : this a_l::A::factoryConstructor(d: d, s: s)
+    ;
+  constructor factoryConstructor({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    : a_l::A::d = d, a_l::A::_s = s, super core::Object::•()
+    ;
+  static method _#new#tearOff({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    return new a_l::A::•(d: d, s: s);
+  static method _#factoryConstructor#tearOff({core::double d = #C1, (core::String) → core::String s = #C2}) → a_l::A
+    return new a_l::A::factoryConstructor(d: d, s: s);
+  method doStringy(core::String i) → core::String
+    return let final core::String #t1 = i in this.{a_l::A::_s}(#t1){(core::String) → core::String};
+}
+static method _defaultStringy(core::String t) → core::String
+  return t.{core::String::toLowerCase}(){() → core::String};
+
+library /*isNonNullableByDefault*/;
+import self as self2;
+import "dart:core" as core;
+
+typedef StringyFunction<contravariant T extends core::Object? = dynamic> = (T%) → core::String;
+
+constants  {
+  #C1 = 3.14
+  #C2 = static-tearoff a_l::_defaultStringy
+  #C3 = 2.71
+}
diff --git a/pkg/front_end/testcases/dart2js/mixin_default_values/t_lib.dart b/pkg/front_end/testcases/dart2js/mixin_default_values/t_lib.dart
new file mode 100644
index 0000000..ab0db0e
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_default_values/t_lib.dart
@@ -0,0 +1,5 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+typedef StringyFunction<T> = String Function(T item);
diff --git a/pkg/front_end/testcases/dart2js/mixin_default_values/test.options b/pkg/front_end/testcases/dart2js/mixin_default_values/test.options
new file mode 100644
index 0000000..d8aba59
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_default_values/test.options
@@ -0,0 +1,2 @@
+a_lib.dart
+t_lib.dart
diff --git a/pkg/front_end/testcases/dart2js/mixin_from_opt_in/main.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/mixin_from_opt_in/main.dart.weak.modular.expect
new file mode 100644
index 0000000..ccdd90a
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_from_opt_in/main.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "test_lib.dart" as tes;
+
+import "org-dartlang-testcase:///test_lib.dart";
+
+static method main() → dynamic {
+  tes::test();
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/dart2js/mixin_from_opt_in/test_lib.dart:10:27: Error: The value 'null' can't be assigned to the parameter type 'int' because 'int' is not nullable.
+//   int j = sub.mixinMethod(null);
+//                           ^
+//
+// pkg/front_end/testcases/dart2js/mixin_from_opt_in/test_lib.dart:10:15: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+//   int j = sub.mixinMethod(null);
+//               ^
+//
+// pkg/front_end/testcases/dart2js/mixin_from_opt_in/test_lib.dart:12:25: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+//   sub.mixinField2 = sub.mixinField1;
+//                         ^
+//
+import self as tes;
+import "opt_out_lib.dart" as opt;
+import "dart:core" as core;
+import "opt_in_lib.dart" as opt2;
+
+import "org-dartlang-testcase:///opt_out_lib.dart";
+
+static method test() → dynamic {
+  opt::SubClass sub = new opt::SubClass::•();
+  core::int i = sub.{opt::_SubClass&Class&Mixin::classMethod}(null){(core::int*) →* core::int*};
+  core::int j = invalid-expression "pkg/front_end/testcases/dart2js/mixin_from_opt_in/test_lib.dart:10:15: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+  int j = sub.mixinMethod(null);
+              ^" in sub.{opt2::Mixin::mixinMethod}(invalid-expression "pkg/front_end/testcases/dart2js/mixin_from_opt_in/test_lib.dart:10:27: Error: The value 'null' can't be assigned to the parameter type 'int' because 'int' is not nullable.
+  int j = sub.mixinMethod(null);
+                          ^" in null as{TypeError,ForNonNullableByDefault} core::int){(core::int) → core::int?} as{TypeError,ForNonNullableByDefault} core::int;
+  sub.{opt::_SubClass&Class&Mixin::classField2} = sub.{opt::_SubClass&Class&Mixin::classField1}{core::int*};
+  sub.{opt2::Mixin::mixinField2} = invalid-expression "pkg/front_end/testcases/dart2js/mixin_from_opt_in/test_lib.dart:12:25: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+  sub.mixinField2 = sub.mixinField1;
+                        ^" in sub.{opt2::Mixin::mixinField1}{core::int?} as{TypeError,ForNonNullableByDefault} core::int;
+}
diff --git a/pkg/front_end/testcases/dart2js/mixin_from_opt_in/main.no_link.dart.weak.modular.expect b/pkg/front_end/testcases/dart2js/mixin_from_opt_in/main.no_link.dart.weak.modular.expect
new file mode 100644
index 0000000..4f8699d
--- /dev/null
+++ b/pkg/front_end/testcases/dart2js/mixin_from_opt_in/main.no_link.dart.weak.modular.expect
@@ -0,0 +1,86 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "test_lib.dart" as tes;
+
+import "org-dartlang-testcase:///test_lib.dart";
+
+static method main() → dynamic {
+  tes::test();
+}
+
+library /*isNonNullableByDefault*/;
+import self as tes;
+import "opt_out_lib.dart" as opt;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///opt_out_lib.dart";
+
+static method test() → dynamic {
+  opt::SubClass sub = new opt::SubClass::•();
+  core::int i = sub.{opt::_SubClass&Class&Mixin::classMethod}(null){(core::int*) →* core::int*};
+  core::int j = sub.{opt::_SubClass&Class&Mixin::mixinMethod}(null){(core::int*) →* core::int*};
+  sub.{opt::_SubClass&Class&Mixin::classField2} = sub.{opt::_SubClass&Class&Mixin::classField1}{core::int*};
+  sub.{opt::_SubClass&Class&Mixin::mixinField2} = sub.{opt::_SubClass&Class&Mixin::mixinField1}{core::int*};
+}
+
+library;
+import self as opt;
+import "opt_in_lib.dart" as opt2;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///opt_in_lib.dart";
+
+abstract class _SubClass&Class&Mixin = opt2::Class with opt2::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → opt::_SubClass&Class&Mixin*
+    : super opt2::Class::•()
+    ;
+  mixin-super-stub get mixinField1() → core::int*
+    return super.{opt2::Mixin::mixinField1};
+  mixin-super-stub set mixinField1(core::int* value) → void
+    return super.{opt2::Mixin::mixinField1} = value;
+  mixin-super-stub get mixinField2() → core::int*
+    return super.{opt2::Mixin::mixinField2};
+  mixin-super-stub set mixinField2(core::int* value) → void
+    return super.{opt2::Mixin::mixinField2} = value;
+  abstract member-signature get classField1() → core::int*; -> opt2::Class::classField1
+  abstract member-signature set classField1(core::int* value) → void; -> opt2::Class::classField1
+  abstract member-signature get classField2() → core::int*; -> opt2::Class::classField2
+  abstract member-signature set classField2(core::int* value) → void; -> opt2::Class::classField2
+  mixin-super-stub method mixinMethod(core::int* i) → core::int*
+    return super.{opt2::Mixin::mixinMethod}(i);
+  abstract member-signature method classMethod(core::int* i) → core::int*; -> opt2::Class::classMethod
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class SubClass extends opt::_SubClass&Class&Mixin {
+  synthetic constructor •() → opt::SubClass*
+    : super opt::_SubClass&Class&Mixin::•()
+    ;
+  static method _#new#tearOff() → opt::SubClass*
+    return new opt::SubClass::•();
+}
+
+library /*isNonNullableByDefault*/;
+import self as opt2;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int? classField1 = null;
+  field core::int classField2 = 0;
+  synthetic constructor •() → opt2::Class
+    : super core::Object::•()
+    ;
+  method classMethod(core::int i) → core::int? {}
+  static method _#new#tearOff() → opt2::Class
+    return new opt2::Class::•();
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+  field core::int? mixinField1 = null;
+  field core::int mixinField2 = 0;
+  method mixinMethod(core::int i) → core::int? {
+    super.{core::Object::toString}();
+  }
+}
diff --git a/pkg/front_end/testcases/dartdevc/conditional_import.dart.weak.modular.expect b/pkg/front_end/testcases/dartdevc/conditional_import.dart.weak.modular.expect
new file mode 100644
index 0000000..3b668f7
--- /dev/null
+++ b/pkg/front_end/testcases/dartdevc/conditional_import.dart.weak.modular.expect
@@ -0,0 +1,84 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/dartdevc/conditional_import.dart:18:11: Error: The getter 'readyState' isn't defined for the class 'HttpRequest'.
+//  - 'HttpRequest' is from 'dart:_http'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'readyState'.
+//   request.readyState; // ok (from dart:html)
+//           ^^^^^^^^^^
+//
+// pkg/front_end/testcases/dartdevc/conditional_import.dart:23:11: Error: The getter 'certificate' isn't defined for the class 'HttpRequest'.
+//  - 'HttpRequest' is from 'pkg/front_end/testcases/dartdevc/conditional_import.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'certificate'.
+//   request.certificate; // error
+//           ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/dartdevc/conditional_import.dart:24:11: Error: The getter 'response' isn't defined for the class 'HttpRequest'.
+//  - 'HttpRequest' is from 'pkg/front_end/testcases/dartdevc/conditional_import.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'response'.
+//   request.response; // error
+//           ^^^^^^^^
+//
+// pkg/front_end/testcases/dartdevc/conditional_import.dart:25:11: Error: The getter 'readyState' isn't defined for the class 'HttpRequest'.
+//  - 'HttpRequest' is from 'pkg/front_end/testcases/dartdevc/conditional_import.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'readyState'.
+//   request.readyState; // error
+//           ^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_http" as _ht;
+import "dart:io" as io;
+
+import "dart:io" as a;
+import "org-dartlang-testcase:///conditional_import.dart" as b;
+
+class HttpRequest extends core::Object {
+  synthetic constructor •() → self::HttpRequest
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff() → self::HttpRequest
+    return new self::HttpRequest::•();
+}
+static method testA(_ht::HttpRequest request) → dynamic {
+  request.{_ht::HttpRequest::certificate}{io::X509Certificate?};
+  request.{_ht::HttpRequest::response}{_ht::HttpResponse};
+  invalid-expression "pkg/front_end/testcases/dartdevc/conditional_import.dart:18:11: Error: The getter 'readyState' isn't defined for the class 'HttpRequest'.
+ - 'HttpRequest' is from 'dart:_http'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'readyState'.
+  request.readyState; // ok (from dart:html)
+          ^^^^^^^^^^" in request{<unresolved>}.readyState;
+  request.{core::Object::hashCode}{core::int};
+}
+static method testB(self::HttpRequest request) → dynamic {
+  invalid-expression "pkg/front_end/testcases/dartdevc/conditional_import.dart:23:11: Error: The getter 'certificate' isn't defined for the class 'HttpRequest'.
+ - 'HttpRequest' is from 'pkg/front_end/testcases/dartdevc/conditional_import.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'certificate'.
+  request.certificate; // error
+          ^^^^^^^^^^^" in request{<unresolved>}.certificate;
+  invalid-expression "pkg/front_end/testcases/dartdevc/conditional_import.dart:24:11: Error: The getter 'response' isn't defined for the class 'HttpRequest'.
+ - 'HttpRequest' is from 'pkg/front_end/testcases/dartdevc/conditional_import.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'response'.
+  request.response; // error
+          ^^^^^^^^" in request{<unresolved>}.response;
+  invalid-expression "pkg/front_end/testcases/dartdevc/conditional_import.dart:25:11: Error: The getter 'readyState' isn't defined for the class 'HttpRequest'.
+ - 'HttpRequest' is from 'pkg/front_end/testcases/dartdevc/conditional_import.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'readyState'.
+  request.readyState; // error
+          ^^^^^^^^^^" in request{<unresolved>}.readyState;
+  request.{core::Object::hashCode}{core::int};
+}
+static method main() → void {
+  self::expect(false, #C1);
+  self::expect(true, #C1);
+  self::expect(false, #C1);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = false
+}
diff --git a/pkg/front_end/testcases/dartdevc/factory_patch/main.dart.weak.modular.expect b/pkg/front_end/testcases/dartdevc/factory_patch/main.dart.weak.modular.expect
new file mode 100644
index 0000000..3eaf932
--- /dev/null
+++ b/pkg/front_end/testcases/dartdevc/factory_patch/main.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:test" as test;
+
+import "dart:test";
+
+static method main() → dynamic {
+  test::Class::fact();
+}
+
+library /*isNonNullableByDefault*/;
+import self as test;
+import "dart:_js_helper" as _js;
+import "dart:core" as core;
+
+import "dart:_js_helper";
+
+@#C1
+class Class extends core::Object {
+  final field core::bool defaultValue /* from org-dartlang-testcase:///patch_lib.dart */;
+  const constructor _internal({core::bool defaultValue = #C2}) → test::Class
+    : test::Class::defaultValue = defaultValue, super core::Object::•()
+    ;
+  @#C1
+  static factory /* from org-dartlang-testcase:///patch_lib.dart */ fact({core::bool defaultValue = #C3}) → test::Class
+    return new test::Class::_internal(defaultValue: defaultValue);
+  static method _#fact#tearOff({core::bool defaultValue = #C3}) → test::Class
+    return test::Class::fact(defaultValue: defaultValue);
+  @#C1
+  static factory /* from org-dartlang-testcase:///patch_lib.dart */ constFact({core::bool defaultValue = #C3}) → test::Class
+    return throw "unsupported";
+  static method _#constFact#tearOff({core::bool defaultValue = #C3}) → test::Class
+    return test::Class::constFact(defaultValue: defaultValue);
+  static method /* from org-dartlang-testcase:///patch_lib.dart */ _#_internal#tearOff({core::bool defaultValue = #C2}) → test::Class
+    return new test::Class::_internal(defaultValue: defaultValue);
+}
+
+constants  {
+  #C1 = _js::_Patch {}
+  #C2 = false
+  #C3 = true
+}
diff --git a/pkg/front_end/testcases/dartdevc/instance_getter_invocation.dart.weak.modular.expect b/pkg/front_end/testcases/dartdevc/instance_getter_invocation.dart.weak.modular.expect
new file mode 100644
index 0000000..d249938
--- /dev/null
+++ b/pkg/front_end/testcases/dartdevc/instance_getter_invocation.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  get idFunction() → <S extends core::Object? = dynamic>(S%) → S%
+    return #C1;
+  get dynFunction() → dynamic
+    return #C1;
+  static method _#new#tearOff() → self::Class
+    return new self::Class::•();
+}
+static method id<T extends core::Object? = dynamic>(self::id::T% t) → self::id::T%
+  return t;
+static method main() → dynamic {
+  self::Class c = new self::Class::•();
+  let final self::Class #t1 = c in let final core::int #t2 = 0 in #t1.{self::Class::idFunction}<core::int>(#t2){(core::int) → core::int};
+  let final self::Class #t3 = c in let final core::int #t4 = 0 in #t3.{self::Class::idFunction}<core::int>(#t4){(core::int) → core::int};
+  let final self::Class #t5 = c in let final core::int #t6 = 0 in #t5.{self::Class::dynFunction}(#t6);
+}
+
+constants  {
+  #C1 = static-tearoff self::id
+}
diff --git a/pkg/front_end/testcases/dartdevc/issue47108.dart.weak.modular.expect b/pkg/front_end/testcases/dartdevc/issue47108.dart.weak.modular.expect
new file mode 100644
index 0000000..39841ce
--- /dev/null
+++ b/pkg/front_end/testcases/dartdevc/issue47108.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<T extends core::Object? = dynamic>() → self::C<self::C::_#new#tearOff::T%>
+    return new self::C::•<self::C::_#new#tearOff::T%>();
+}
+static const field <T extends core::Object? = dynamic>() → self::C<T%> constructorTearOff = #C1;
+static method main() → dynamic {
+  const () → self::C<core::int> instantiatedTearOff = #C2;
+  const () → self::C<core::int> instantiatedTearOff2 = #C2;
+  core::print(core::identical(instantiatedTearOff, instantiatedTearOff2));
+  core::print(core::identical(#C3, #C3));
+}
+
+constants  {
+  #C1 = static-tearoff self::C::_#new#tearOff
+  #C2 = instantiation #C1 <core::int*>
+  #C3 = instantiation #C1 <core::String*>
+}
diff --git a/pkg/front_end/testcases/dartdevc/issue47313.dart.weak.modular.expect b/pkg/front_end/testcases/dartdevc/issue47313.dart.weak.modular.expect
new file mode 100644
index 0000000..26cc49c
--- /dev/null
+++ b/pkg/front_end/testcases/dartdevc/issue47313.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff<X extends core::Object? = dynamic>() → self::A<self::A::_#new#tearOff::X%>
+    return new self::A::•<self::A::_#new#tearOff::X%>();
+}
+abstract class M extends core::Object /*isMixinDeclaration*/  {
+}
+class C<X extends core::Object? = dynamic> = self::A<self::C::X%> with self::M {
+  synthetic constructor •() → self::C<self::C::X%>
+    : super self::A::•()
+    ;
+  static method _#new#tearOff<X extends core::Object? = dynamic>() → self::C<self::C::_#new#tearOff::X%>
+    return new self::C::•<self::C::_#new#tearOff::X%>();
+}
+static method main() → dynamic {
+  #C1;
+}
+
+constants  {
+  #C1 = static-tearoff self::C::_#new#tearOff
+}
diff --git a/pkg/front_end/testcases/dartdevc/private_covariant.dart.weak.modular.expect b/pkg/front_end/testcases/dartdevc/private_covariant.dart.weak.modular.expect
new file mode 100644
index 0000000..aaaca01
--- /dev/null
+++ b/pkg/front_end/testcases/dartdevc/private_covariant.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  method _privateMethod(covariant-by-declaration core::int i) → dynamic {}
+  static method _#new#tearOff() → self::Class
+    return new self::Class::•();
+}
+static method main() → dynamic {
+  new self::Class::•().{self::Class::_privateMethod}(0){(core::int) → dynamic};
+}
diff --git a/pkg/front_end/testcases/dartdevc/symbol.dart.weak.modular.expect b/pkg/front_end/testcases/dartdevc/symbol.dart.weak.modular.expect
new file mode 100644
index 0000000..d827f5b
--- /dev/null
+++ b/pkg/front_end/testcases/dartdevc/symbol.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:_internal" as _in;
+
+static method main() → dynamic
+  return #C1;
+
+constants  {
+  #C1 = #a
+}
diff --git a/pkg/front_end/testcases/enhanced_enums/entries_with_type_arguments.dart.weak.modular.expect b/pkg/front_end/testcases/enhanced_enums/entries_with_type_arguments.dart.weak.modular.expect
new file mode 100644
index 0000000..a7d67d3
--- /dev/null
+++ b/pkg/front_end/testcases/enhanced_enums/entries_with_type_arguments.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class E extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::E> values = #C10;
+  static const field self::E one = #C3;
+  static const field self::E two = #C6;
+  static const field self::E three = #C9;
+  const constructor •(core::int index, core::String name) → self::E
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String
+    return "E.${this.{core::_Enum::_name}{core::String}}";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+  #C2 = "one"
+  #C3 = self::E {index:#C1, _name:#C2}
+  #C4 = 1
+  #C5 = "two"
+  #C6 = self::E {index:#C4, _name:#C5}
+  #C7 = 2
+  #C8 = "three"
+  #C9 = self::E {index:#C7, _name:#C8}
+  #C10 = <self::E*>[#C3, #C6, #C9]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///entries_with_type_arguments.dart:
+- E. (from org-dartlang-testcase:///entries_with_type_arguments.dart:5:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:76:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/enhanced_enums/qualified_names_with_no_type_arguments.dart.weak.modular.expect b/pkg/front_end/testcases/enhanced_enums/qualified_names_with_no_type_arguments.dart.weak.modular.expect
new file mode 100644
index 0000000..5cc89c4
--- /dev/null
+++ b/pkg/front_end/testcases/enhanced_enums/qualified_names_with_no_type_arguments.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class E extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::E> values = #C4;
+  static const field self::E a = #C3;
+  const constructor •(core::int index, core::String name) → self::E
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String
+    return "E.${this.{core::_Enum::_name}{core::String}}";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+  #C2 = "a"
+  #C3 = self::E {index:#C1, _name:#C2}
+  #C4 = <self::E*>[#C3]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///qualified_names_with_no_type_arguments.dart:
+- E. (from org-dartlang-testcase:///qualified_names_with_no_type_arguments.dart:5:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:76:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/extension_types/access_setter_as_getter.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/access_setter_as_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..cd89df1
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/access_setter_as_getter.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extension_types/access_setter_as_getter.dart:16:5: Error: The getter 'foo' isn't defined for the extension 'E'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'foo'.
+//   e.foo; // Error.
+//     ^^^
+//
+// pkg/front_end/testcases/extension_types/access_setter_as_getter.dart:17:5: Error: The setter 'bar' isn't defined for the extension 'E'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'bar'.
+//   e.bar = 42; // Error.
+//     ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+extension E on self::A {
+  get bar = self::E|get#bar;
+  set foo = self::E|set#foo;
+}
+static method E|set#foo(lowered final self::A #this, core::int value) → void {}
+static method E|get#bar(lowered final self::A #this) → core::int
+  return 42;
+static method test(self::E e) → dynamic {
+  self::E|set#foo(e, 42);
+  self::E|get#bar(e);
+  invalid-expression "pkg/front_end/testcases/extension_types/access_setter_as_getter.dart:16:5: Error: The getter 'foo' isn't defined for the extension 'E'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'foo'.
+  e.foo; // Error.
+    ^^^" in e{<unresolved>}.foo;
+  invalid-expression "pkg/front_end/testcases/extension_types/access_setter_as_getter.dart:17:5: Error: The setter 'bar' isn't defined for the extension 'E'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'bar'.
+  e.bar = 42; // Error.
+    ^^^" in e{<unresolved>}.bar = 42;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/basic_show.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/basic_show.dart.weak.modular.expect
new file mode 100644
index 0000000..35387e0
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/basic_show.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extension_types/basic_show.dart:9:26: Error: Expected an identifier, but got '{'.
+// Try inserting an identifier before '{'.
+// extension E3 on int show {} // Error.
+//                          ^
+//
+// pkg/front_end/testcases/extension_types/basic_show.dart:13:31: Error: Expected an identifier, but got '{'.
+// Try inserting an identifier before '{'.
+// extension E5 on int show num, {} // Error.
+//                               ^
+//
+// pkg/front_end/testcases/extension_types/basic_show.dart:15:26: Error: Expected an identifier, but got ','.
+// Try inserting an identifier before ','.
+// extension E6 on int show , num {} // Error.
+//                          ^
+//
+// pkg/front_end/testcases/extension_types/basic_show.dart:15:28: Error: A extension declaration must have a body, even if it is empty.
+// Try adding an empty body.
+// extension E6 on int show , num {} // Error.
+//                            ^^^
+//
+// pkg/front_end/testcases/extension_types/basic_show.dart:15:28: Error: A function declaration needs an explicit list of parameters.
+// Try adding a parameter list to the function declaration.
+// extension E6 on int show , num {} // Error.
+//                            ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+extension E1 on core::int show-types core::num {
+}
+extension E2 on core::int {
+}
+extension E3 on core::int {
+}
+extension E4 on core::int show-types core::num {
+}
+extension E5 on core::int show-types core::num {
+}
+extension E6 on core::int {
+}
+static method num() → dynamic {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/call_not_get.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/call_not_get.dart.weak.modular.expect
new file mode 100644
index 0000000..a787e50
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/call_not_get.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extension_types/call_not_get.dart:9:5: Error: The method 'ceil' isn't defined for the extension 'E'.
+// Try correcting the name to the name of an existing method, or defining a method name 'ceil'.
+//   e.ceil(); // Error.
+//     ^^^^
+//
+// pkg/front_end/testcases/extension_types/call_not_get.dart:10:5: Error: The setter 'ceil' isn't defined for the extension 'E'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'ceil'.
+//   e.ceil = 42; // Error.
+//     ^^^^
+//
+// pkg/front_end/testcases/extension_types/call_not_get.dart:12:5: Error: The getter 'floor' isn't defined for the extension 'E'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'floor'.
+//   e.floor; // Error.
+//     ^^^^^
+//
+// pkg/front_end/testcases/extension_types/call_not_get.dart:14:5: Error: The setter 'ceil' isn't defined for the extension 'E'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'ceil'.
+//   e.ceil = 42; // Error.
+//     ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+extension type E on core::int show-methods core::int::floor show-getters core::int::floor, core::int::ceil hide-getters core::int::floor {
+}
+static method test(self::E e) → dynamic {
+  e.{core::int::ceil}{() → core::int};
+  invalid-expression "pkg/front_end/testcases/extension_types/call_not_get.dart:9:5: Error: The method 'ceil' isn't defined for the extension 'E'.
+Try correcting the name to the name of an existing method, or defining a method name 'ceil'.
+  e.ceil(); // Error.
+    ^^^^" in e{<unresolved>}.ceil();
+  invalid-expression "pkg/front_end/testcases/extension_types/call_not_get.dart:10:5: Error: The setter 'ceil' isn't defined for the extension 'E'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'ceil'.
+  e.ceil = 42; // Error.
+    ^^^^" in e{<unresolved>}.ceil = 42;
+  invalid-expression "pkg/front_end/testcases/extension_types/call_not_get.dart:12:5: Error: The getter 'floor' isn't defined for the extension 'E'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'floor'.
+  e.floor; // Error.
+    ^^^^^" in e{<unresolved>}.floor;
+  e.{core::int::floor}(){() → core::int};
+  invalid-expression "pkg/front_end/testcases/extension_types/call_not_get.dart:14:5: Error: The setter 'ceil' isn't defined for the extension 'E'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'ceil'.
+  e.ceil = 42; // Error.
+    ^^^^" in e{<unresolved>}.ceil = 42;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/extension_on_nullable.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/extension_on_nullable.dart.weak.modular.expect
new file mode 100644
index 0000000..3074033
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/extension_on_nullable.dart.weak.modular.expect
@@ -0,0 +1,19 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+extension E on self::A? {
+  method foo = self::E|foo;
+  tearoff foo = self::E|get#foo;
+}
+static method E|foo(lowered final self::A? #this) → void {}
+static method E|get#foo(lowered final self::A? #this) → () → void
+  return () → void => self::E|foo(#this);
+static method bar(self::E e) → dynamic
+  return self::E|foo(e);
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/extension_with_name_type.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/extension_with_name_type.dart.weak.modular.expect
new file mode 100644
index 0000000..626118a
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/extension_with_name_type.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+extension type on self::A {
+  method method = self::type|method;
+  tearoff method = self::type|get#method;
+}
+static method type|method(lowered final self::A #this) → dynamic {}
+static method type|get#method(lowered final self::A #this) → () → dynamic
+  return () → dynamic => self::type|method(#this);
+static method test() → dynamic {
+  self::type|method(new self::A::•());
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/issue45775.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/issue45775.dart.weak.modular.expect
new file mode 100644
index 0000000..4e10ba8
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/issue45775.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → self::Foo
+    : super core::Object::•()
+    ;
+}
+extension Bar on self::Foo {
+}
+static method main() → void {
+  self::Bar bar = new self::Foo::•();
+}
diff --git a/pkg/front_end/testcases/extension_types/keyword_in_show_hide_element.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/keyword_in_show_hide_element.dart.weak.modular.expect
new file mode 100644
index 0000000..6111f5a
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/keyword_in_show_hide_element.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method mixin() → void {}
+  method as() → void {}
+}
+extension type E1 on self::A show-methods self::A::as, self::A::mixin show-getters self::A::as, self::A::mixin {
+}
+extension type E2 on self::A hide-methods self::A::as, self::A::mixin hide-getters self::A::as, self::A::mixin {
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/show_and_run_ceil.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/show_and_run_ceil.dart.weak.modular.expect
new file mode 100644
index 0000000..61492c2
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/show_and_run_ceil.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+extension E on core::double show-types core::num {
+}
+static method expectIdentical(dynamic a, dynamic b) → dynamic {
+  if(!core::identical(a, b)) {
+    throw "Expected '${a}' and '${b}' to be identical.";
+  }
+}
+static method test(self::E e, core::int value) → dynamic {
+  self::expectIdentical(e.{core::num::ceil}(){() → core::int}, value);
+}
+static method main() → dynamic {
+  self::test(3.14, 4);
+}
diff --git a/pkg/front_end/testcases/extension_types/show_hide_all_kinds.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/show_hide_all_kinds.dart.weak.modular.expect
new file mode 100644
index 0000000..ba0e4db
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/show_hide_all_kinds.dart.weak.modular.expect
@@ -0,0 +1,70 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+}
+class B<X extends core::Object? = dynamic> extends self::A<self::B::X%> {
+  synthetic constructor •() → self::B<self::B::X%>
+    : super self::A::•()
+    ;
+}
+class C extends self::B<core::int> {
+  synthetic constructor •() → self::C
+    : super self::B::•()
+    ;
+}
+class A2 extends core::Object {
+  synthetic constructor •() → self::A2
+    : super core::Object::•()
+    ;
+}
+class B2 extends self::A2 {
+  synthetic constructor •() → self::B2
+    : super self::A2::•()
+    ;
+}
+class C2 extends self::B2 {
+  synthetic constructor •() → self::C2
+    : super self::B2::•()
+    ;
+}
+class A3 extends core::Object {
+  field core::int? field = null;
+  field core::String? field2 = null;
+  synthetic constructor •() → self::A3
+    : super core::Object::•()
+    ;
+  method foo() → void {}
+  get getter() → core::int
+    return 42;
+  set setter(core::int value) → void {}
+  set setter2(core::int value) → void {}
+  set setter3(core::int value) → void {}
+  operator +(self::A3 other) → self::A3
+    return other;
+  operator *(self::A3 other) → self::A3
+    return this;
+}
+class B3 extends self::A3 {
+  synthetic constructor •() → self::B3
+    : super self::A3::•()
+    ;
+  method bar() → void {}
+}
+class C3 extends self::B3 {
+  synthetic constructor •() → self::C3
+    : super self::B3::•()
+    ;
+  method baz() → void {}
+}
+extension type E on self::C show-types self::B<core::int> hide-types self::A<core::int> {
+}
+extension type E2 on self::C2 show-types self::B2 hide-types self::A2 {
+}
+extension type E3 on self::C3 show-types self::B3 show-methods self::C3::baz show-getters self::A3::field, self::C3::baz show-setters self::A3::setter, self::A3::field, self::A3::field2 show-operators self::A3::+ hide-methods self::A3::foo hide-getters self::A3::getter, self::A3::foo, self::A3::field hide-setters self::A3::setter2, self::A3::setter3 hide-operators self::A3::* {
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/simple.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/simple.dart.weak.modular.expect
new file mode 100644
index 0000000..8f038ec
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/simple.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Foo<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Foo<self::Foo::X%>
+    : super core::Object::•()
+    ;
+}
+class Bar<X extends core::Object? = dynamic, Y extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Bar<self::Bar::X%, self::Bar::Y%>
+    : super core::Object::•()
+    ;
+}
+extension A1 on dynamic {
+}
+extension A2<X extends core::Object? = dynamic> on self::Foo<X%> {
+}
+extension A3<X extends core::Object? = dynamic, Y extends (X%) → dynamic = (Never) → dynamic> on self::Bar<X%, Y> {
+}
+extension A4<X extends core::Object? = dynamic, Y extends (X%) → dynamic = (Never) → dynamic> on self::Foo<Y> {
+}
+static method foo1(self::A1 a) → self::A1
+  return throw 42;
+static method foo2(self::A2<core::int> a, self::A2<dynamic> ai) → self::A2<dynamic>
+  return throw 42;
+static method foo3(self::A3<core::int, (core::num) → dynamic> a, self::A3<dynamic, (Never) → dynamic> ai) → self::A3<dynamic, (Never) → dynamic>
+  return throw 42;
+static method foo4(self::A4<core::int, (core::num) → dynamic> a, self::A4<dynamic, (Never) → dynamic> ai) → self::A4<dynamic, (Never) → dynamic>
+  return throw 42;
+static method bar() → dynamic {
+  self::A1 a1;
+  self::A2<core::int> a2;
+  self::A2<dynamic> a2i;
+  self::A3<core::int, (core::num) → dynamic> a3;
+  self::A3<dynamic, (Never) → dynamic> a3i;
+  self::A4<core::int, (core::num) → dynamic> a4;
+  self::A4<dynamic, (Never) → dynamic> a4i;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/simple_getter_resolution.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/simple_getter_resolution.dart.weak.modular.expect
new file mode 100644
index 0000000..b762cd5
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/simple_getter_resolution.dart.weak.modular.expect
@@ -0,0 +1,78 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extension_types/simple_getter_resolution.dart:20:5: Error: The getter 'baz' isn't defined for the class 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/extension_types/simple_getter_resolution.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'baz'.
+//   a.baz; // Error.
+//     ^^^
+//
+// pkg/front_end/testcases/extension_types/simple_getter_resolution.dart:22:5: Error: The getter 'foo' isn't defined for the extension 'E'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'foo'.
+//   e.foo; // Error.
+//     ^^^
+//
+// pkg/front_end/testcases/extension_types/simple_getter_resolution.dart:24:5: Error: The getter 'baz' isn't defined for the extension 'E'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'baz'.
+//   e.baz; // Error.
+//     ^^^
+//
+// pkg/front_end/testcases/extension_types/simple_getter_resolution.dart:26:6: Error: The getter 'foo' isn't defined for the extension 'ET'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'foo'.
+//   et.foo; // Error.
+//      ^^^
+//
+// pkg/front_end/testcases/extension_types/simple_getter_resolution.dart:27:6: Error: The getter 'bar' isn't defined for the extension 'ET'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'bar'.
+//   et.bar; // Error.
+//      ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  get foo() → core::int
+    return 42;
+}
+extension E on self::A {
+  get bar = self::E|get#bar;
+}
+extension type ET on self::A {
+  get baz = self::ET|get#baz;
+}
+static method E|get#bar(lowered final self::A #this) → core::double
+  return 3.14;
+static method ET|get#baz(lowered final self::A #this) → core::String
+  return "baz";
+static method test(self::A a, self::E e, self::ET et) → dynamic {
+  a.{self::A::foo}{core::int};
+  self::E|get#bar(a);
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_getter_resolution.dart:20:5: Error: The getter 'baz' isn't defined for the class 'A'.
+ - 'A' is from 'pkg/front_end/testcases/extension_types/simple_getter_resolution.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'baz'.
+  a.baz; // Error.
+    ^^^" in a{<unresolved>}.baz;
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_getter_resolution.dart:22:5: Error: The getter 'foo' isn't defined for the extension 'E'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'foo'.
+  e.foo; // Error.
+    ^^^" in e{<unresolved>}.foo;
+  self::E|get#bar(e);
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_getter_resolution.dart:24:5: Error: The getter 'baz' isn't defined for the extension 'E'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'baz'.
+  e.baz; // Error.
+    ^^^" in e{<unresolved>}.baz;
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_getter_resolution.dart:26:6: Error: The getter 'foo' isn't defined for the extension 'ET'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'foo'.
+  et.foo; // Error.
+     ^^^" in et{<unresolved>}.foo;
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_getter_resolution.dart:27:6: Error: The getter 'bar' isn't defined for the extension 'ET'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'bar'.
+  et.bar; // Error.
+     ^^^" in et{<unresolved>}.bar;
+  self::ET|get#baz(et);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/simple_method_resolution.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/simple_method_resolution.dart.weak.modular.expect
new file mode 100644
index 0000000..ae7cf69
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/simple_method_resolution.dart.weak.modular.expect
@@ -0,0 +1,83 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extension_types/simple_method_resolution.dart:20:5: Error: The method 'baz' isn't defined for the class 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/extension_types/simple_method_resolution.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'baz'.
+//   a.baz(); // Error.
+//     ^^^
+//
+// pkg/front_end/testcases/extension_types/simple_method_resolution.dart:22:5: Error: The method 'foo' isn't defined for the extension 'E'.
+// Try correcting the name to the name of an existing method, or defining a method name 'foo'.
+//   e.foo(); // Error.
+//     ^^^
+//
+// pkg/front_end/testcases/extension_types/simple_method_resolution.dart:24:5: Error: The method 'baz' isn't defined for the extension 'E'.
+// Try correcting the name to the name of an existing method, or defining a method name 'baz'.
+//   e.baz(); // Error.
+//     ^^^
+//
+// pkg/front_end/testcases/extension_types/simple_method_resolution.dart:26:6: Error: The method 'foo' isn't defined for the extension 'ET'.
+// Try correcting the name to the name of an existing method, or defining a method name 'foo'.
+//   et.foo(); // Error.
+//      ^^^
+//
+// pkg/front_end/testcases/extension_types/simple_method_resolution.dart:27:6: Error: The method 'bar' isn't defined for the extension 'ET'.
+// Try correcting the name to the name of an existing method, or defining a method name 'bar'.
+//   et.bar(); // Error.
+//      ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method foo() → void {}
+}
+extension E on self::A {
+  method bar = self::E|bar;
+  tearoff bar = self::E|get#bar;
+}
+extension type ET on self::A {
+  method baz = self::ET|baz;
+  tearoff baz = self::ET|get#baz;
+}
+static method E|bar(lowered final self::A #this) → void
+  return #this.{self::A::foo}(){() → void};
+static method E|get#bar(lowered final self::A #this) → () → void
+  return () → void => self::E|bar(#this);
+static method ET|baz(lowered final self::A #this) → void
+  return #this.{self::A::foo}(){() → void};
+static method ET|get#baz(lowered final self::A #this) → () → void
+  return () → void => self::ET|baz(#this);
+static method test(self::A a, self::E e, self::ET et) → dynamic {
+  a.{self::A::foo}(){() → void};
+  self::E|bar(a);
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_method_resolution.dart:20:5: Error: The method 'baz' isn't defined for the class 'A'.
+ - 'A' is from 'pkg/front_end/testcases/extension_types/simple_method_resolution.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'baz'.
+  a.baz(); // Error.
+    ^^^" in a{<unresolved>}.baz();
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_method_resolution.dart:22:5: Error: The method 'foo' isn't defined for the extension 'E'.
+Try correcting the name to the name of an existing method, or defining a method name 'foo'.
+  e.foo(); // Error.
+    ^^^" in e{<unresolved>}.foo();
+  self::E|bar(e);
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_method_resolution.dart:24:5: Error: The method 'baz' isn't defined for the extension 'E'.
+Try correcting the name to the name of an existing method, or defining a method name 'baz'.
+  e.baz(); // Error.
+    ^^^" in e{<unresolved>}.baz();
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_method_resolution.dart:26:6: Error: The method 'foo' isn't defined for the extension 'ET'.
+Try correcting the name to the name of an existing method, or defining a method name 'foo'.
+  et.foo(); // Error.
+     ^^^" in et{<unresolved>}.foo();
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_method_resolution.dart:27:6: Error: The method 'bar' isn't defined for the extension 'ET'.
+Try correcting the name to the name of an existing method, or defining a method name 'bar'.
+  et.bar(); // Error.
+     ^^^" in et{<unresolved>}.bar();
+  self::ET|baz(et);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/simple_operator_resolution.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/simple_operator_resolution.dart.weak.modular.expect
new file mode 100644
index 0000000..8a58ea2
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/simple_operator_resolution.dart.weak.modular.expect
@@ -0,0 +1,140 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:26:5: Error: The operator '~/' isn't defined for the class 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/extension_types/simple_operator_resolution.dart'.
+// Try correcting the operator to an existing operator, or defining a '~/' operator.
+//   a ~/ "foobar"; // Error.
+//     ^^
+//
+// pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:28:5: Error: The operator '*' isn't defined for the extension 'E'.
+// Try correcting the operator to an existing operator, or defining a '*' operator.
+//   e * "foobar"; // Error.
+//     ^
+//
+// pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:29:4: Error: The operator '[]' isn't defined for the extension 'E'.
+// Try correcting the operator to an existing operator, or defining a '[]' operator.
+//   e[0]; // Error.
+//    ^
+//
+// pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:30:4: Error: The operator '[]=' isn't defined for the extension 'E'.
+// Try correcting the operator to an existing operator, or defining a '[]=' operator.
+//   e[0] = "foobar"; // Error.
+//    ^
+//
+// pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:31:3: Error: The operator 'unary-' isn't defined for the extension 'E'.
+// Try correcting the operator to an existing operator, or defining a 'unary-' operator.
+//   -e; // Error.
+//   ^
+//
+// pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:33:5: Error: The operator '~/' isn't defined for the extension 'E'.
+// Try correcting the operator to an existing operator, or defining a '~/' operator.
+//   e ~/ "foobar"; // Error.
+//     ^^
+//
+// pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:35:6: Error: The operator '*' isn't defined for the extension 'ET'.
+// Try correcting the operator to an existing operator, or defining a '*' operator.
+//   et * "foobar"; // Error.
+//      ^
+//
+// pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:36:5: Error: The operator '[]' isn't defined for the extension 'ET'.
+// Try correcting the operator to an existing operator, or defining a '[]' operator.
+//   et[0]; // Error.
+//     ^
+//
+// pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:37:5: Error: The operator '[]=' isn't defined for the extension 'ET'.
+// Try correcting the operator to an existing operator, or defining a '[]=' operator.
+//   et[0] = "foobar"; // Error.
+//     ^
+//
+// pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:38:3: Error: The operator 'unary-' isn't defined for the extension 'ET'.
+// Try correcting the operator to an existing operator, or defining a 'unary-' operator.
+//   -et; // Error.
+//   ^
+//
+// pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:39:6: Error: The operator '+' isn't defined for the extension 'ET'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//   et + "foobar"; // Error.
+//      ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  operator *(dynamic other) → dynamic
+    return 42;
+  operator [](core::int index) → dynamic
+    return 42;
+  operator []=(core::int index, dynamic value) → void {}
+  operator unary-() → dynamic
+    return 42;
+}
+extension E on self::A {
+  operator + = self::E|+;
+}
+extension type ET on self::A {
+  operator ~/ = self::ET|~/;
+}
+static method E|+(lowered final self::A #this, dynamic other) → dynamic
+  return 42;
+static method ET|~/(lowered final self::A #this, dynamic other) → dynamic
+  return 42;
+static method test(self::A a, self::E e, self::ET et) → dynamic {
+  a.{self::A::*}("foobar"){(dynamic) → dynamic};
+  a.{self::A::[]}(0){(core::int) → dynamic};
+  a.{self::A::[]=}(0, "foobar"){(core::int, dynamic) → void};
+  a.{self::A::unary-}(){() → dynamic};
+  self::E|+(a, "foobar");
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:26:5: Error: The operator '~/' isn't defined for the class 'A'.
+ - 'A' is from 'pkg/front_end/testcases/extension_types/simple_operator_resolution.dart'.
+Try correcting the operator to an existing operator, or defining a '~/' operator.
+  a ~/ \"foobar\"; // Error.
+    ^^" in a{<unresolved>}.~/("foobar");
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:28:5: Error: The operator '*' isn't defined for the extension 'E'.
+Try correcting the operator to an existing operator, or defining a '*' operator.
+  e * \"foobar\"; // Error.
+    ^" in e{<unresolved>}.*("foobar");
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:29:4: Error: The operator '[]' isn't defined for the extension 'E'.
+Try correcting the operator to an existing operator, or defining a '[]' operator.
+  e[0]; // Error.
+   ^" in e{<unresolved>}.[](0);
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:30:4: Error: The operator '[]=' isn't defined for the extension 'E'.
+Try correcting the operator to an existing operator, or defining a '[]=' operator.
+  e[0] = \"foobar\"; // Error.
+   ^" in e{<unresolved>}.[]=(0, "foobar");
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:31:3: Error: The operator 'unary-' isn't defined for the extension 'E'.
+Try correcting the operator to an existing operator, or defining a 'unary-' operator.
+  -e; // Error.
+  ^" in e{<unresolved>}.unary-();
+  self::E|+(e, "foobar");
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:33:5: Error: The operator '~/' isn't defined for the extension 'E'.
+Try correcting the operator to an existing operator, or defining a '~/' operator.
+  e ~/ \"foobar\"; // Error.
+    ^^" in e{<unresolved>}.~/("foobar");
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:35:6: Error: The operator '*' isn't defined for the extension 'ET'.
+Try correcting the operator to an existing operator, or defining a '*' operator.
+  et * \"foobar\"; // Error.
+     ^" in et{<unresolved>}.*("foobar");
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:36:5: Error: The operator '[]' isn't defined for the extension 'ET'.
+Try correcting the operator to an existing operator, or defining a '[]' operator.
+  et[0]; // Error.
+    ^" in et{<unresolved>}.[](0);
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:37:5: Error: The operator '[]=' isn't defined for the extension 'ET'.
+Try correcting the operator to an existing operator, or defining a '[]=' operator.
+  et[0] = \"foobar\"; // Error.
+    ^" in et{<unresolved>}.[]=(0, "foobar");
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:38:3: Error: The operator 'unary-' isn't defined for the extension 'ET'.
+Try correcting the operator to an existing operator, or defining a 'unary-' operator.
+  -et; // Error.
+  ^" in et{<unresolved>}.unary-();
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_operator_resolution.dart:39:6: Error: The operator '+' isn't defined for the extension 'ET'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+  et + \"foobar\"; // Error.
+     ^" in et{<unresolved>}.+("foobar");
+  self::ET|~/(et, "foobar");
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/simple_setter_resolution.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/simple_setter_resolution.dart.weak.modular.expect
new file mode 100644
index 0000000..c9c618e
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/simple_setter_resolution.dart.weak.modular.expect
@@ -0,0 +1,77 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extension_types/simple_setter_resolution.dart:26:3: Error: Undefined name 'et'.
+//   et.foo = 42; // Error.
+//   ^^
+//
+// pkg/front_end/testcases/extension_types/simple_setter_resolution.dart:27:3: Error: Undefined name 'et'.
+//   et.bar = 42; // Error.
+//   ^^
+//
+// pkg/front_end/testcases/extension_types/simple_setter_resolution.dart:28:3: Error: Undefined name 'et'.
+//   et.baz = 42; // Ok.
+//   ^^
+//
+// pkg/front_end/testcases/extension_types/simple_setter_resolution.dart:20:5: Error: The setter 'baz' isn't defined for the class 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/extension_types/simple_setter_resolution.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'baz'.
+//   a.baz = 42; // Error.
+//     ^^^
+//
+// pkg/front_end/testcases/extension_types/simple_setter_resolution.dart:22:5: Error: The setter 'foo' isn't defined for the extension 'E'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'foo'.
+//   e.foo = 42; // Error.
+//     ^^^
+//
+// pkg/front_end/testcases/extension_types/simple_setter_resolution.dart:24:5: Error: The setter 'baz' isn't defined for the extension 'E'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'baz'.
+//   e.baz = 42; // Error.
+//     ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  set foo(core::int value) → void {}
+}
+extension E on self::A {
+  set bar = self::E|set#bar;
+}
+extension type ET on self::A {
+  set baz = self::ET|set#baz;
+}
+static method E|set#bar(lowered final self::A #this, core::int value) → void {}
+static method ET|set#baz(lowered final self::A #this, core::int value) → void {}
+static method test(self::A a, self::E e) → dynamic {
+  a.{self::A::foo} = 42;
+  self::E|set#bar(a, 42);
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_setter_resolution.dart:20:5: Error: The setter 'baz' isn't defined for the class 'A'.
+ - 'A' is from 'pkg/front_end/testcases/extension_types/simple_setter_resolution.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'baz'.
+  a.baz = 42; // Error.
+    ^^^" in a{<unresolved>}.baz = 42;
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_setter_resolution.dart:22:5: Error: The setter 'foo' isn't defined for the extension 'E'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'foo'.
+  e.foo = 42; // Error.
+    ^^^" in e{<unresolved>}.foo = 42;
+  self::E|set#bar(e, 42);
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_setter_resolution.dart:24:5: Error: The setter 'baz' isn't defined for the extension 'E'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'baz'.
+  e.baz = 42; // Error.
+    ^^^" in e{<unresolved>}.baz = 42;
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_setter_resolution.dart:26:3: Error: Undefined name 'et'.
+  et.foo = 42; // Error.
+  ^^"{<invalid>}.foo = 42;
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_setter_resolution.dart:27:3: Error: Undefined name 'et'.
+  et.bar = 42; // Error.
+  ^^"{<invalid>}.bar = 42;
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_setter_resolution.dart:28:3: Error: Undefined name 'et'.
+  et.baz = 42; // Ok.
+  ^^"{<invalid>}.baz = 42;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/simple_show_and_hide.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/simple_show_and_hide.dart.weak.modular.expect
new file mode 100644
index 0000000..a785e78
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/simple_show_and_hide.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class I1<X extends core::Object? = dynamic, Y extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::I1<self::I1::X%, self::I1::Y%>
+    : super core::Object::•()
+    ;
+}
+class I2<X extends core::Object? = dynamic, Y extends core::Object? = dynamic, Z extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::I2<self::I2::X%, self::I2::Y%, self::I2::Z%>
+    : super core::Object::•()
+    ;
+}
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class B extends self::A implements self::I1<core::int, core::int> {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+  method methodB() → void {}
+  method methodB2() → void {}
+  get getterB() → core::int
+    return throw 42;
+  set setterB(core::int value) → void {}
+  operator *(self::B other) → self::B
+    return throw 42;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C
+    : super self::B::•()
+    ;
+}
+class D extends self::C implements self::I2<core::int, core::int, core::int> {
+  synthetic constructor •() → self::D
+    : super self::C::•()
+    ;
+  method methodD() → void {}
+  get getterD() → core::int
+    return throw 42;
+  set setterD(core::int value) → void {}
+  operator +(self::D other) → self::D
+    return throw 42;
+}
+extension type E on self::D show-types self::I2<core::int, core::int, core::int>, self::C show-methods self::D::methodD show-getters self::D::methodD, self::D::getterD show-setters self::D::setterD show-operators self::D::+ hide-types self::I1<core::int, core::int>, self::A hide-methods self::B::methodB2, self::B::methodB hide-getters self::B::methodB2, self::B::methodB, self::B::getterB hide-setters self::B::setterB hide-operators self::B::* {
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/simple_show_hide.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/simple_show_hide.dart.weak.modular.expect
new file mode 100644
index 0000000..a7bbb4c
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/simple_show_hide.dart.weak.modular.expect
@@ -0,0 +1,95 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extension_types/simple_show_hide.dart:9:3: Error: Undefined name 'e2'.
+//   e2.floor(); // Ok.
+//   ^^
+//
+// pkg/front_end/testcases/extension_types/simple_show_hide.dart:10:6: Error: The getter 'isEven' isn't defined for the extension 'E1'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'isEven'.
+//   e1.isEven; // Error.
+//      ^^^^^^
+//
+// pkg/front_end/testcases/extension_types/simple_show_hide.dart:16:6: Error: The method 'ceil' isn't defined for the extension 'E2'.
+// Try correcting the name to the name of an existing method, or defining a method name 'ceil'.
+//   e2.ceil(); // Error.
+//      ^^^^
+//
+// pkg/front_end/testcases/extension_types/simple_show_hide.dart:18:6: Error: The getter 'isEven' isn't defined for the extension 'E2'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'isEven'.
+//   e2.isEven; // Error.
+//      ^^^^^^
+//
+// pkg/front_end/testcases/extension_types/simple_show_hide.dart:24:6: Error: The getter 'isOdd' isn't defined for the extension 'E3'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'isOdd'.
+//   e3.isOdd; // Ok.
+//      ^^^^^
+//
+// pkg/front_end/testcases/extension_types/simple_show_hide.dart:25:6: Error: The getter 'isEven' isn't defined for the extension 'E3'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'isEven'.
+//   e3.isEven; // Error.
+//      ^^^^^^
+//
+// pkg/front_end/testcases/extension_types/simple_show_hide.dart:38:5: Error: The method 'floor' isn't defined for the extension 'MyInt'.
+// Try correcting the name to the name of an existing method, or defining a method name 'floor'.
+//   m.floor(); // Error, hidden.
+//     ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+extension E1 on core::int show-types core::num {
+}
+extension E2 on core::int show-types core::num hide-methods core::int::ceil hide-getters core::int::ceil {
+}
+extension E3 on core::int hide-getters core::int::isEven {
+}
+extension type MyInt on core::int show-types core::num show-getters core::int::isEven hide-methods core::int::floor hide-getters core::int::floor {
+  get twice = self::MyInt|get#twice;
+}
+static method test1(self::E1 e1) → dynamic {
+  e1.{core::num::ceil}(){() → core::int};
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_show_hide.dart:9:3: Error: Undefined name 'e2'.
+  e2.floor(); // Ok.
+  ^^"{dynamic}.floor();
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_show_hide.dart:10:6: Error: The getter 'isEven' isn't defined for the extension 'E1'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'isEven'.
+  e1.isEven; // Error.
+     ^^^^^^" in e1{<unresolved>}.isEven;
+}
+static method test2(self::E2 e2) → dynamic {
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_show_hide.dart:16:6: Error: The method 'ceil' isn't defined for the extension 'E2'.
+Try correcting the name to the name of an existing method, or defining a method name 'ceil'.
+  e2.ceil(); // Error.
+     ^^^^" in e2{<unresolved>}.ceil();
+  e2.{core::num::floor}(){() → core::int};
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_show_hide.dart:18:6: Error: The getter 'isEven' isn't defined for the extension 'E2'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'isEven'.
+  e2.isEven; // Error.
+     ^^^^^^" in e2{<unresolved>}.isEven;
+}
+static method test3(self::E3 e3) → dynamic {
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_show_hide.dart:24:6: Error: The getter 'isOdd' isn't defined for the extension 'E3'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'isOdd'.
+  e3.isOdd; // Ok.
+     ^^^^^" in e3{<unresolved>}.isOdd;
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_show_hide.dart:25:6: Error: The getter 'isEven' isn't defined for the extension 'E3'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'isEven'.
+  e3.isEven; // Error.
+     ^^^^^^" in e3{<unresolved>}.isEven;
+}
+static method MyInt|get#twice(lowered final core::int #this) → core::int
+  return 2.{core::num::*}(#this){(core::num) → core::int};
+static method test() → dynamic {
+  self::MyInt m = 42;
+  self::MyInt|get#twice(m);
+  m.{core::int::isEven}{core::bool};
+  m.{core::num::ceil}(){() → core::int};
+  m.{core::Object::toString}(){() → core::String};
+  invalid-expression "pkg/front_end/testcases/extension_types/simple_show_hide.dart:38:5: Error: The method 'floor' isn't defined for the extension 'MyInt'.
+Try correcting the name to the name of an existing method, or defining a method name 'floor'.
+  m.floor(); // Error, hidden.
+    ^^^^^" in m{<unresolved>}.floor();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/simple_show_hide_conflicts.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/simple_show_hide_conflicts.dart.weak.modular.expect
new file mode 100644
index 0000000..70175c9
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/simple_show_hide_conflicts.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extension_types/simple_show_hide_conflicts.dart:6:7: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+//   int ceil() {} // Error.
+//       ^
+//
+// pkg/front_end/testcases/extension_types/simple_show_hide_conflicts.dart:10:7: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+//   int ceil() {} // Ok.
+//       ^
+//
+// pkg/front_end/testcases/extension_types/simple_show_hide_conflicts.dart:11:7: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+//   int floor() {} // Error.
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+extension E1 on core::int show-types core::num {
+  method ceil = self::E1|ceil;
+  tearoff ceil = self::E1|get#ceil;
+}
+extension E2 on core::int show-types core::num hide-methods core::int::ceil hide-getters core::int::ceil {
+  method ceil = self::E2|ceil;
+  tearoff ceil = self::E2|get#ceil;
+  method floor = self::E2|floor;
+  tearoff floor = self::E2|get#floor;
+}
+extension E3 on core::int hide-getters core::int::isEven {
+  get isOdd = self::E3|get#isOdd;
+  get isEven = self::E3|get#isEven;
+}
+static method E1|ceil(lowered final core::int #this) → core::int {
+  return invalid-expression "pkg/front_end/testcases/extension_types/simple_show_hide_conflicts.dart:6:7: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+  int ceil() {} // Error.
+      ^" in null;
+}
+static method E1|get#ceil(lowered final core::int #this) → () → core::int
+  return () → core::int => self::E1|ceil(#this);
+static method E2|ceil(lowered final core::int #this) → core::int {
+  return invalid-expression "pkg/front_end/testcases/extension_types/simple_show_hide_conflicts.dart:10:7: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+  int ceil() {} // Ok.
+      ^" in null;
+}
+static method E2|get#ceil(lowered final core::int #this) → () → core::int
+  return () → core::int => self::E2|ceil(#this);
+static method E2|floor(lowered final core::int #this) → core::int {
+  return invalid-expression "pkg/front_end/testcases/extension_types/simple_show_hide_conflicts.dart:11:7: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+  int floor() {} // Error.
+      ^" in null;
+}
+static method E2|get#floor(lowered final core::int #this) → () → core::int
+  return () → core::int => self::E2|floor(#this);
+static method E3|get#isOdd(lowered final core::int #this) → core::bool
+  return throw 42;
+static method E3|get#isEven(lowered final core::int #this) → core::bool
+  return throw 42;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/type_variable_in_static_context.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/type_variable_in_static_context.dart.weak.modular.expect
new file mode 100644
index 0000000..7f95ca4
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/type_variable_in_static_context.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extension_types/type_variable_in_static_context.dart:8:26: Error: Type variables can't be used in static members.
+//   static A<T>? method1(A<T> arg) {
+//                          ^
+//
+// pkg/front_end/testcases/extension_types/type_variable_in_static_context.dart:8:12: Error: Type variables can't be used in static members.
+//   static A<T>? method1(A<T> arg) {
+//            ^
+//
+// pkg/front_end/testcases/extension_types/type_variable_in_static_context.dart:11:31: Error: Type variables can't be used in static members.
+//   static A<A<T>>? method2(A<A<T>> arg) {
+//                               ^
+//
+// pkg/front_end/testcases/extension_types/type_variable_in_static_context.dart:11:14: Error: Type variables can't be used in static members.
+//   static A<A<T>>? method2(A<A<T>> arg) {
+//              ^
+//
+// pkg/front_end/testcases/extension_types/type_variable_in_static_context.dart:9:7: Error: Type variables can't be used in static members.
+//     A<T>? local;
+//       ^
+//
+// pkg/front_end/testcases/extension_types/type_variable_in_static_context.dart:12:9: Error: Type variables can't be used in static members.
+//     A<A<T>>? local;
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  static method method1(self::A<invalid-type> arg) → self::A<invalid-type>? {
+    self::A<invalid-type>? local;
+  }
+  static method method2(self::A<self::A<invalid-type>> arg) → self::A<self::A<invalid-type>>? {
+    self::A<self::A<invalid-type>>? local;
+  }
+}
+extension type A<T extends core::Object? = dynamic> on self::Class<T%> {
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/various_hide_elements.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/various_hide_elements.dart.weak.modular.expect
new file mode 100644
index 0000000..65db982
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/various_hide_elements.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "dart:core" as prefixedCore;
+import "dart:core";
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  abstract operator *(self::A other) → self::A;
+}
+class B<X extends core::Object? = dynamic> extends core::Object implements self::A {
+  synthetic constructor •() → self::B<self::B::X%>
+    : super core::Object::•()
+    ;
+  get foo() → core::bool
+    return throw 42;
+  operator *(self::A other) → self::A
+    return throw 42;
+}
+class C extends self::B<core::int> {
+  synthetic constructor •() → self::C
+    : super self::B::•()
+    ;
+  set bar(core::int value) → void {}
+  method baz() → void {}
+}
+extension type E0 on core::int hide-operators core::num::* {
+}
+extension type E1 on core::int hide-getters core::int::isEven {
+}
+extension type E2<T extends core::Object? = dynamic> on core::List<T%> hide-setters core::List::length {
+}
+extension type E3 on core::int hide-types core::num {
+}
+extension type E4 on core::List<core::int> hide-types core::Iterable<core::int> {
+}
+extension type E5 on core::List<dynamic> hide-types core::Iterable<dynamic> {
+}
+extension type E6 on core::List<core::int> hide-types core::Iterable<core::int> {
+}
+extension type E on self::C hide-types self::B<core::int> hide-methods self::C::baz hide-getters self::C::baz, self::B::foo hide-setters self::C::bar hide-operators self::B::* {
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extension_types/various_show_elements.dart.weak.modular.expect b/pkg/front_end/testcases/extension_types/various_show_elements.dart.weak.modular.expect
new file mode 100644
index 0000000..0aae661
--- /dev/null
+++ b/pkg/front_end/testcases/extension_types/various_show_elements.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "dart:core" as prefixedCore;
+import "dart:core";
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  abstract operator *(self::A other) → self::A;
+}
+class B<X extends core::Object? = dynamic> extends core::Object implements self::A {
+  synthetic constructor •() → self::B<self::B::X%>
+    : super core::Object::•()
+    ;
+  get foo() → core::bool
+    return throw 42;
+  operator *(self::A other) → self::A
+    return throw 42;
+}
+class C extends self::B<core::int> {
+  synthetic constructor •() → self::C
+    : super self::B::•()
+    ;
+  set bar(core::int value) → void {}
+  method baz() → void {}
+}
+extension type E0 on core::int show-operators core::num::* {
+}
+extension type E1 on core::int show-getters core::int::isEven {
+}
+extension type E2<T extends core::Object? = dynamic> on core::List<T%> show-setters core::List::length {
+}
+extension type E3 on core::int show-types core::num {
+}
+extension type E4 on core::List<core::int> show-types core::Iterable<core::int> {
+}
+extension type E5 on core::List<dynamic> show-types core::Iterable<dynamic> {
+}
+extension type E6 on core::List<core::int> show-types core::Iterable<core::int> {
+}
+extension type E on self::C show-types self::B<core::int> show-methods self::C::baz show-getters self::C::baz, self::B::foo show-setters self::C::bar show-operators self::B::* {
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/ambiguous.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/ambiguous.dart.weak.modular.expect
new file mode 100644
index 0000000..1dca435
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/ambiguous.dart.weak.modular.expect
@@ -0,0 +1,275 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/ambiguous.dart:28:5: Error: The method 'method' is defined in multiple extensions for 'C' and neither is more specific.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   c.method();
+//     ^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:6:8: Context: This is one of the extension members.
+//   void method() {}
+//        ^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:16:8: Context: This is one of the extension members.
+//   void method() {}
+//        ^^^^^^
+//
+// pkg/front_end/testcases/extensions/ambiguous.dart:29:5: Error: The property 'method' is defined in multiple extensions for 'C' and neither is more specific.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   c.method;
+//     ^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:6:8: Context: This is one of the extension members.
+//   void method() {}
+//        ^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:16:8: Context: This is one of the extension members.
+//   void method() {}
+//        ^^^^^^
+//
+// pkg/front_end/testcases/extensions/ambiguous.dart:30:5: Error: The property 'getter' is defined in multiple extensions for 'C' and neither is more specific.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   c.getter;
+//     ^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:7:11: Context: This is one of the extension members.
+//   int get getter => 42;
+//           ^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:17:11: Context: This is one of the extension members.
+//   int get getter => 42;
+//           ^^^^^^
+//
+// pkg/front_end/testcases/extensions/ambiguous.dart:31:5: Error: The property 'setter' is defined in multiple extensions for 'C' and neither is more specific.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   c.setter;
+//     ^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:8:12: Context: This is one of the extension members.
+//   void set setter(int value) {}
+//            ^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:18:12: Context: This is one of the extension members.
+//   void set setter(int value) {}
+//            ^^^^^^
+//
+// pkg/front_end/testcases/extensions/ambiguous.dart:32:5: Error: The property 'getter' is defined in multiple extensions for 'C' and neither is more specific.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   c.getter = 42;
+//     ^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:7:11: Context: This is one of the extension members.
+//   int get getter => 42;
+//           ^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:17:11: Context: This is one of the extension members.
+//   int get getter => 42;
+//           ^^^^^^
+//
+// pkg/front_end/testcases/extensions/ambiguous.dart:33:5: Error: The property 'setter' is defined in multiple extensions for 'C' and neither is more specific.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   c.setter = 42;
+//     ^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:8:12: Context: This is one of the extension members.
+//   void set setter(int value) {}
+//            ^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:18:12: Context: This is one of the extension members.
+//   void set setter(int value) {}
+//            ^^^^^^
+//
+// pkg/front_end/testcases/extensions/ambiguous.dart:34:5: Error: The property 'property' is defined in multiple extensions for 'C' and neither is more specific.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   c.property;
+//     ^^^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:9:11: Context: This is one of the extension members.
+//   int get property => 42;
+//           ^^^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:19:12: Context: This is one of the extension members.
+//   void set property(int value) {}
+//            ^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/ambiguous.dart:35:5: Error: The property 'property' is defined in multiple extensions for 'C' and neither is more specific.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   c.property = 42;
+//     ^^^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:9:11: Context: This is one of the extension members.
+//   int get property => 42;
+//           ^^^^^^^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:19:12: Context: This is one of the extension members.
+//   void set property(int value) {}
+//            ^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/ambiguous.dart:36:5: Error: The operator '+' is defined in multiple extensions for 'C' and neither is more specific.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   c + 0;
+//     ^
+// pkg/front_end/testcases/extensions/ambiguous.dart:10:16: Context: This is one of the extension members.
+//   int operator +(int i) => i;
+//                ^
+// pkg/front_end/testcases/extensions/ambiguous.dart:20:16: Context: This is one of the extension members.
+//   int operator +(int i) => i;
+//                ^
+//
+// pkg/front_end/testcases/extensions/ambiguous.dart:37:3: Error: The operator 'unary-' is defined in multiple extensions for 'C' and neither is more specific.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   -c;
+//   ^
+// pkg/front_end/testcases/extensions/ambiguous.dart:11:16: Context: This is one of the extension members.
+//   int operator -() => 0;
+//                ^
+// pkg/front_end/testcases/extensions/ambiguous.dart:21:16: Context: This is one of the extension members.
+//   int operator -() => 0;
+//                ^
+//
+// pkg/front_end/testcases/extensions/ambiguous.dart:38:4: Error: The operator '[]' is defined in multiple extensions for 'C' and neither is more specific.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   c[42];
+//    ^
+// pkg/front_end/testcases/extensions/ambiguous.dart:12:16: Context: This is one of the extension members.
+//   int operator [](int i) => i;
+//                ^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:22:17: Context: This is one of the extension members.
+//   void operator []=(int i, int j) {}
+//                 ^^^
+//
+// pkg/front_end/testcases/extensions/ambiguous.dart:39:4: Error: The operator '[]=' is defined in multiple extensions for 'C' and neither is more specific.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   c[42] = 0;
+//    ^
+// pkg/front_end/testcases/extensions/ambiguous.dart:12:16: Context: This is one of the extension members.
+//   int operator [](int i) => i;
+//                ^^
+// pkg/front_end/testcases/extensions/ambiguous.dart:22:17: Context: This is one of the extension members.
+//   void operator []=(int i, int j) {}
+//                 ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension A on self::C* {
+  method method = self::A|method;
+  tearoff method = self::A|get#method;
+  get getter = self::A|get#getter;
+  get property = self::A|get#property;
+  operator + = self::A|+;
+  operator unary- = self::A|unary-;
+  operator [] = self::A|[];
+  set setter = self::A|set#setter;
+}
+extension B on self::C* {
+  method method = self::B|method;
+  tearoff method = self::B|get#method;
+  get getter = self::B|get#getter;
+  operator + = self::B|+;
+  operator unary- = self::B|unary-;
+  operator []= = self::B|[]=;
+  set setter = self::B|set#setter;
+  set property = self::B|set#property;
+}
+static method A|method(lowered final self::C* #this) → void {}
+static method A|get#method(lowered final self::C* #this) → () →* void
+  return () → void => self::A|method(#this);
+static method A|get#getter(lowered final self::C* #this) → core::int*
+  return 42;
+static method A|set#setter(lowered final self::C* #this, core::int* value) → void {}
+static method A|get#property(lowered final self::C* #this) → core::int*
+  return 42;
+static method A|+(lowered final self::C* #this, core::int* i) → core::int*
+  return i;
+static method A|unary-(lowered final self::C* #this) → core::int*
+  return 0;
+static method A|[](lowered final self::C* #this, core::int* i) → core::int*
+  return i;
+static method B|method(lowered final self::C* #this) → void {}
+static method B|get#method(lowered final self::C* #this) → () →* void
+  return () → void => self::B|method(#this);
+static method B|get#getter(lowered final self::C* #this) → core::int*
+  return 42;
+static method B|set#setter(lowered final self::C* #this, core::int* value) → void {}
+static method B|set#property(lowered final self::C* #this, core::int* value) → void {}
+static method B|+(lowered final self::C* #this, core::int* i) → core::int*
+  return i;
+static method B|unary-(lowered final self::C* #this) → core::int*
+  return 0;
+static method B|[]=(lowered final self::C* #this, core::int* i, core::int* j) → void {}
+static method errors(self::C* c) → dynamic {
+  invalid-expression "pkg/front_end/testcases/extensions/ambiguous.dart:28:5: Error: The method 'method' is defined in multiple extensions for 'C' and neither is more specific.
+ - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  c.method();
+    ^^^^^^" in c{<unresolved>}.method();
+  invalid-expression "pkg/front_end/testcases/extensions/ambiguous.dart:29:5: Error: The property 'method' is defined in multiple extensions for 'C' and neither is more specific.
+ - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  c.method;
+    ^^^^^^" in c{<unresolved>}.method;
+  invalid-expression "pkg/front_end/testcases/extensions/ambiguous.dart:30:5: Error: The property 'getter' is defined in multiple extensions for 'C' and neither is more specific.
+ - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  c.getter;
+    ^^^^^^" in c{<unresolved>}.getter;
+  invalid-expression "pkg/front_end/testcases/extensions/ambiguous.dart:31:5: Error: The property 'setter' is defined in multiple extensions for 'C' and neither is more specific.
+ - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  c.setter;
+    ^^^^^^" in c{<unresolved>}.setter;
+  invalid-expression "pkg/front_end/testcases/extensions/ambiguous.dart:32:5: Error: The property 'getter' is defined in multiple extensions for 'C' and neither is more specific.
+ - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  c.getter = 42;
+    ^^^^^^" in c{<unresolved>}.getter = 42;
+  invalid-expression "pkg/front_end/testcases/extensions/ambiguous.dart:33:5: Error: The property 'setter' is defined in multiple extensions for 'C' and neither is more specific.
+ - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  c.setter = 42;
+    ^^^^^^" in c{<unresolved>}.setter = 42;
+  invalid-expression "pkg/front_end/testcases/extensions/ambiguous.dart:34:5: Error: The property 'property' is defined in multiple extensions for 'C' and neither is more specific.
+ - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  c.property;
+    ^^^^^^^^" in c{<unresolved>}.property;
+  invalid-expression "pkg/front_end/testcases/extensions/ambiguous.dart:35:5: Error: The property 'property' is defined in multiple extensions for 'C' and neither is more specific.
+ - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  c.property = 42;
+    ^^^^^^^^" in c{<unresolved>}.property = 42;
+  invalid-expression "pkg/front_end/testcases/extensions/ambiguous.dart:36:5: Error: The operator '+' is defined in multiple extensions for 'C' and neither is more specific.
+ - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  c + 0;
+    ^" in c{<unresolved>}.+(0);
+  invalid-expression "pkg/front_end/testcases/extensions/ambiguous.dart:37:3: Error: The operator 'unary-' is defined in multiple extensions for 'C' and neither is more specific.
+ - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  -c;
+  ^" in c{<unresolved>}.unary-();
+  invalid-expression "pkg/front_end/testcases/extensions/ambiguous.dart:38:4: Error: The operator '[]' is defined in multiple extensions for 'C' and neither is more specific.
+ - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  c[42];
+   ^" in c{<unresolved>}.[](42);
+  invalid-expression "pkg/front_end/testcases/extensions/ambiguous.dart:39:4: Error: The operator '[]=' is defined in multiple extensions for 'C' and neither is more specific.
+ - 'C' is from 'pkg/front_end/testcases/extensions/ambiguous.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  c[42] = 0;
+   ^" in c{<unresolved>}.[]=(42, 0);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/annotations.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/annotations.dart.weak.modular.expect
new file mode 100644
index 0000000..61a26a4
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/annotations.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  @#C3
+  method instanceMethod() → dynamic {}
+  @#C3
+  static method staticMethod() → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+  method extensionInstanceMethod = self::Extension|extensionInstanceMethod;
+  tearoff extensionInstanceMethod = self::Extension|get#extensionInstanceMethod;
+  static method extensionStaticMethod = self::Extension|extensionStaticMethod;
+}
+@#C3
+static method Extension|extensionInstanceMethod(lowered final self::Class* #this) → dynamic {}
+static method Extension|get#extensionInstanceMethod(lowered final self::Class* #this) → () →* dynamic
+  return () → dynamic => self::Extension|extensionInstanceMethod(#this);
+@#C3
+static method Extension|extensionStaticMethod() → dynamic {}
+@#C3
+static method topLevelMethod() → dynamic {}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = "dart2js:noInline"
+  #C2 = null
+  #C3 = core::pragma {name:#C1, options:#C2}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///annotations.dart:
+- pragma._ (from org-dartlang-sdk:///sdk/lib/core/annotations.dart:188:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/extensions/annotations_scope.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/annotations_scope.dart.weak.modular.expect
new file mode 100644
index 0000000..1fc63c7
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/annotations_scope.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+extension E on core::int {
+  static field constField = self::E|constField;
+  static field constField1 = self::E|constField1;
+  static field constField2 = self::E|constField2;
+  static method staticMethod = self::E|staticMethod;
+  method instanceMethod = self::E|instanceMethod;
+  tearoff instanceMethod = self::E|get#instanceMethod;
+}
+@#C1
+static const field core::int E|constField = #C1;
+@#C2
+static const field core::int E|constField1 = #C3;
+@#C3
+static const field core::int E|constField2 = #C2;
+@#C1
+static method E|staticMethod() → void {}
+@#C1
+static method E|instanceMethod(lowered final core::int #this) → void {}
+static method E|get#instanceMethod(lowered final core::int #this) → () → void
+  return () → void => self::E|instanceMethod(#this);
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 1
+  #C2 = 3
+  #C3 = 2
+}
diff --git a/pkg/front_end/testcases/extensions/async_extensions.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/async_extensions.dart.weak.modular.expect
new file mode 100644
index 0000000..f053e58
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/async_extensions.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+extension Extension on core::int* {
+  method syncStarMethod = self::Extension|syncStarMethod;
+  tearoff syncStarMethod = self::Extension|get#syncStarMethod;
+  method asyncMethod = self::Extension|asyncMethod;
+  tearoff asyncMethod = self::Extension|get#asyncMethod;
+  method asyncStarMethod = self::Extension|asyncStarMethod;
+  tearoff asyncStarMethod = self::Extension|get#asyncStarMethod;
+}
+static method Extension|syncStarMethod(lowered final core::int* #this) → dynamic sync* {}
+static method Extension|get#syncStarMethod(lowered final core::int* #this) → () →* dynamic
+  return () → dynamic => self::Extension|syncStarMethod(#this);
+static method Extension|asyncMethod(lowered final core::int* #this) → dynamic async {}
+static method Extension|get#asyncMethod(lowered final core::int* #this) → () →* dynamic
+  return () → dynamic => self::Extension|asyncMethod(#this);
+static method Extension|asyncStarMethod(lowered final core::int* #this) → dynamic async* {}
+static method Extension|get#asyncStarMethod(lowered final core::int* #this) → () →* dynamic
+  return () → dynamic => self::Extension|asyncStarMethod(#this);
+static method main() → dynamic {
+  self::Extension|syncStarMethod(0);
+  self::Extension|get#syncStarMethod(0);
+  self::Extension|asyncMethod(0);
+  self::Extension|get#asyncMethod(0);
+  self::Extension|asyncStarMethod(0);
+  self::Extension|get#asyncStarMethod(0);
+}
diff --git a/pkg/front_end/testcases/extensions/bounds.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/bounds.dart.weak.modular.expect
new file mode 100644
index 0000000..8c13b5c
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/bounds.dart.weak.modular.expect
@@ -0,0 +1,93 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+extension Extension1<T extends core::Object*> on T* {
+  method method1 = self::Extension1|method1;
+  tearoff method1 = self::Extension1|get#method1;
+  method method2 = self::Extension1|method2;
+  tearoff method2 = self::Extension1|get#method2;
+  method method3 = self::Extension1|method3;
+  tearoff method3 = self::Extension1|get#method3;
+  method method4 = self::Extension1|method4;
+  tearoff method4 = self::Extension1|get#method4;
+}
+extension Extension2<T extends core::String*> on T* {
+  method method1 = self::Extension2|method1;
+  tearoff method1 = self::Extension2|get#method1;
+  method method2 = self::Extension2|method2;
+  tearoff method2 = self::Extension2|get#method2;
+  method method3 = self::Extension2|method3;
+  tearoff method3 = self::Extension2|get#method3;
+  method method4 = self::Extension2|method4;
+  tearoff method4 = self::Extension2|get#method4;
+}
+extension Extension3<T extends dynamic> on T* {
+  method method1 = self::Extension3|method1;
+  tearoff method1 = self::Extension3|get#method1;
+  method method2 = self::Extension3|method2;
+  tearoff method2 = self::Extension3|get#method2;
+  method method3 = self::Extension3|method3;
+  tearoff method3 = self::Extension3|get#method3;
+  method method4 = self::Extension3|method4;
+  tearoff method4 = self::Extension3|get#method4;
+}
+extension Extension4<T extends core::Object* = dynamic> on T* {
+  method method1 = self::Extension4|method1;
+  tearoff method1 = self::Extension4|get#method1;
+  method method2 = self::Extension4|method2;
+  tearoff method2 = self::Extension4|get#method2;
+  method method3 = self::Extension4|method3;
+  tearoff method3 = self::Extension4|get#method3;
+  method method4 = self::Extension4|method4;
+  tearoff method4 = self::Extension4|get#method4;
+}
+static method Extension1|method1<T extends core::Object*, S extends core::Object*>(lowered final self::Extension1|method1::T* #this) → dynamic {}
+static method Extension1|get#method1<T extends core::Object*>(lowered final self::Extension1|get#method1::T* #this) → <S extends core::Object*>() →* dynamic
+  return <S extends core::Object*>() → dynamic => self::Extension1|method1<self::Extension1|get#method1::T*, S*>(#this);
+static method Extension1|method2<T extends core::Object*, S extends core::String*>(lowered final self::Extension1|method2::T* #this) → dynamic {}
+static method Extension1|get#method2<T extends core::Object*>(lowered final self::Extension1|get#method2::T* #this) → <S extends core::String*>() →* dynamic
+  return <S extends core::String*>() → dynamic => self::Extension1|method2<self::Extension1|get#method2::T*, S*>(#this);
+static method Extension1|method3<T extends core::Object*, S extends dynamic>(lowered final self::Extension1|method3::T* #this) → dynamic {}
+static method Extension1|get#method3<T extends core::Object*>(lowered final self::Extension1|get#method3::T* #this) → <S extends dynamic>() →* dynamic
+  return <S extends dynamic>() → dynamic => self::Extension1|method3<self::Extension1|get#method3::T*, S%>(#this);
+static method Extension1|method4<T extends core::Object*, S extends core::Object* = dynamic>(lowered final self::Extension1|method4::T* #this) → dynamic {}
+static method Extension1|get#method4<T extends core::Object*>(lowered final self::Extension1|get#method4::T* #this) → <S extends core::Object* = dynamic>() →* dynamic
+  return <S extends core::Object* = dynamic>() → dynamic => self::Extension1|method4<self::Extension1|get#method4::T*, S*>(#this);
+static method Extension2|method1<T extends core::String*, S extends core::Object*>(lowered final self::Extension2|method1::T* #this) → dynamic {}
+static method Extension2|get#method1<T extends core::String*>(lowered final self::Extension2|get#method1::T* #this) → <S extends core::Object*>() →* dynamic
+  return <S extends core::Object*>() → dynamic => self::Extension2|method1<self::Extension2|get#method1::T*, S*>(#this);
+static method Extension2|method2<T extends core::String*, S extends core::String*>(lowered final self::Extension2|method2::T* #this) → dynamic {}
+static method Extension2|get#method2<T extends core::String*>(lowered final self::Extension2|get#method2::T* #this) → <S extends core::String*>() →* dynamic
+  return <S extends core::String*>() → dynamic => self::Extension2|method2<self::Extension2|get#method2::T*, S*>(#this);
+static method Extension2|method3<T extends core::String*, S extends dynamic>(lowered final self::Extension2|method3::T* #this) → dynamic {}
+static method Extension2|get#method3<T extends core::String*>(lowered final self::Extension2|get#method3::T* #this) → <S extends dynamic>() →* dynamic
+  return <S extends dynamic>() → dynamic => self::Extension2|method3<self::Extension2|get#method3::T*, S%>(#this);
+static method Extension2|method4<T extends core::String*, S extends core::Object* = dynamic>(lowered final self::Extension2|method4::T* #this) → dynamic {}
+static method Extension2|get#method4<T extends core::String*>(lowered final self::Extension2|get#method4::T* #this) → <S extends core::Object* = dynamic>() →* dynamic
+  return <S extends core::Object* = dynamic>() → dynamic => self::Extension2|method4<self::Extension2|get#method4::T*, S*>(#this);
+static method Extension3|method1<T extends dynamic, S extends core::Object*>(lowered final self::Extension3|method1::T* #this) → dynamic {}
+static method Extension3|get#method1<T extends dynamic>(lowered final self::Extension3|get#method1::T* #this) → <S extends core::Object*>() →* dynamic
+  return <S extends core::Object*>() → dynamic => self::Extension3|method1<self::Extension3|get#method1::T%, S*>(#this);
+static method Extension3|method2<T extends dynamic, S extends core::String*>(lowered final self::Extension3|method2::T* #this) → dynamic {}
+static method Extension3|get#method2<T extends dynamic>(lowered final self::Extension3|get#method2::T* #this) → <S extends core::String*>() →* dynamic
+  return <S extends core::String*>() → dynamic => self::Extension3|method2<self::Extension3|get#method2::T%, S*>(#this);
+static method Extension3|method3<T extends dynamic, S extends dynamic>(lowered final self::Extension3|method3::T* #this) → dynamic {}
+static method Extension3|get#method3<T extends dynamic>(lowered final self::Extension3|get#method3::T* #this) → <S extends dynamic>() →* dynamic
+  return <S extends dynamic>() → dynamic => self::Extension3|method3<self::Extension3|get#method3::T%, S%>(#this);
+static method Extension3|method4<T extends dynamic, S extends core::Object* = dynamic>(lowered final self::Extension3|method4::T* #this) → dynamic {}
+static method Extension3|get#method4<T extends dynamic>(lowered final self::Extension3|get#method4::T* #this) → <S extends core::Object* = dynamic>() →* dynamic
+  return <S extends core::Object* = dynamic>() → dynamic => self::Extension3|method4<self::Extension3|get#method4::T%, S*>(#this);
+static method Extension4|method1<T extends core::Object* = dynamic, S extends core::Object*>(lowered final self::Extension4|method1::T* #this) → dynamic {}
+static method Extension4|get#method1<T extends core::Object* = dynamic>(lowered final self::Extension4|get#method1::T* #this) → <S extends core::Object*>() →* dynamic
+  return <S extends core::Object*>() → dynamic => self::Extension4|method1<self::Extension4|get#method1::T*, S*>(#this);
+static method Extension4|method2<T extends core::Object* = dynamic, S extends core::String*>(lowered final self::Extension4|method2::T* #this) → dynamic {}
+static method Extension4|get#method2<T extends core::Object* = dynamic>(lowered final self::Extension4|get#method2::T* #this) → <S extends core::String*>() →* dynamic
+  return <S extends core::String*>() → dynamic => self::Extension4|method2<self::Extension4|get#method2::T*, S*>(#this);
+static method Extension4|method3<T extends core::Object* = dynamic, S extends dynamic>(lowered final self::Extension4|method3::T* #this) → dynamic {}
+static method Extension4|get#method3<T extends core::Object* = dynamic>(lowered final self::Extension4|get#method3::T* #this) → <S extends dynamic>() →* dynamic
+  return <S extends dynamic>() → dynamic => self::Extension4|method3<self::Extension4|get#method3::T*, S%>(#this);
+static method Extension4|method4<T extends core::Object* = dynamic, S extends core::Object* = dynamic>(lowered final self::Extension4|method4::T* #this) → dynamic {}
+static method Extension4|get#method4<T extends core::Object* = dynamic>(lowered final self::Extension4|get#method4::T* #this) → <S extends core::Object* = dynamic>() →* dynamic
+  return <S extends core::Object* = dynamic>() → dynamic => self::Extension4|method4<self::Extension4|get#method4::T*, S*>(#this);
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/builtin_identifiers.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/builtin_identifiers.dart.weak.modular.expect
new file mode 100644
index 0000000..dba880e
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/builtin_identifiers.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/builtin_identifiers.dart:5:11: Error: Can't use 'mixin' as a name here.
+// extension mixin on int {}
+//           ^^^^^
+//
+// pkg/front_end/testcases/extensions/builtin_identifiers.dart:7:11: Error: Can't use 'extension' as a name here.
+// extension extension on int {}
+//           ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/builtin_identifiers.dart:9:11: Error: Can't use 'as' as a name here.
+// extension as on int {}
+//           ^^
+//
+import self as self;
+import "dart:core" as core;
+
+extension mixin on core::int* {
+}
+extension extension on core::int* {
+}
+extension as on core::int* {
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/extensions/call_methods.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/call_methods.dart.weak.modular.expect
new file mode 100644
index 0000000..d38841f
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/call_methods.dart.weak.modular.expect
@@ -0,0 +1,192 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/call_methods.dart:29:18: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+// var topLevel1 = 1(10);
+//                  ^
+//
+// pkg/front_end/testcases/extensions/call_methods.dart:30:18: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+// var topLevel2 = 1("10");
+//                  ^
+//
+// pkg/front_end/testcases/extensions/call_methods.dart:31:20: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+// var topLevel3 = 1.0(10);
+//                    ^
+//
+// pkg/front_end/testcases/extensions/call_methods.dart:32:20: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+// var topLevel4 = 1.0("10");
+//                    ^
+//
+// pkg/front_end/testcases/extensions/call_methods.dart:34:18: Error: Cannot invoke an instance of 'A' because it declares 'call' to be something other than a method.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/call_methods.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+// var topLevel5 = a(2);
+//                  ^
+//
+// pkg/front_end/testcases/extensions/call_methods.dart:36:18: Error: Cannot invoke an instance of 'A' because it declares 'call' to be something other than a method.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/call_methods.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+// var topLevel6 = a(2, "3");
+//                  ^
+//
+// pkg/front_end/testcases/extensions/call_methods.dart:39:4: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//   1(10);
+//    ^
+//
+// pkg/front_end/testcases/extensions/call_methods.dart:40:4: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//   1("10");
+//    ^
+//
+// pkg/front_end/testcases/extensions/call_methods.dart:41:6: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//   1.0(10);
+//      ^
+//
+// pkg/front_end/testcases/extensions/call_methods.dart:42:6: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//   1.0("10");
+//      ^
+//
+// pkg/front_end/testcases/extensions/call_methods.dart:44:4: Error: Cannot invoke an instance of 'A' because it declares 'call' to be something other than a method.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/call_methods.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+//   a(2);
+//    ^
+//
+// pkg/front_end/testcases/extensions/call_methods.dart:45:4: Error: Cannot invoke an instance of 'A' because it declares 'call' to be something other than a method.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/call_methods.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+//   a(2, "3");
+//    ^
+//
+// pkg/front_end/testcases/extensions/call_methods.dart:47:4: Error: Cannot invoke an instance of 'B' because it declares 'call' to be something other than a method.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/call_methods.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+//   b();
+//    ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  get call() → core::String*
+    return "My name is A";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  get call() → () →* core::String*
+    return () → core::String* => "My name is B";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension _extension#0 on core::int* {
+  get call = self::_extension#0|get#call;
+}
+extension _extension#1 on core::num* {
+  get call = self::_extension#1|get#call;
+}
+extension _extension#2 on core::String* {
+  get call = self::_extension#2|get#call;
+}
+static field core::String* topLevel1 = invalid-expression "pkg/front_end/testcases/extensions/call_methods.dart:29:18: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+var topLevel1 = 1(10);
+                 ^" in self::_extension#2|get#call(self::_extension#0|get#call(1)){<inapplicable>}.(10);
+static field core::String* topLevel2 = invalid-expression "pkg/front_end/testcases/extensions/call_methods.dart:30:18: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+var topLevel2 = 1(\"10\");
+                 ^" in self::_extension#2|get#call(self::_extension#0|get#call(1)){<inapplicable>}.("10");
+static field core::String* topLevel3 = invalid-expression "pkg/front_end/testcases/extensions/call_methods.dart:31:20: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+var topLevel3 = 1.0(10);
+                   ^" in self::_extension#2|get#call(self::_extension#1|get#call(1.0)){<inapplicable>}.(10);
+static field core::String* topLevel4 = invalid-expression "pkg/front_end/testcases/extensions/call_methods.dart:32:20: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+var topLevel4 = 1.0(\"10\");
+                   ^" in self::_extension#2|get#call(self::_extension#1|get#call(1.0)){<inapplicable>}.("10");
+static field self::A* a = new self::A::•();
+static field invalid-type topLevel5 = invalid-expression "pkg/front_end/testcases/extensions/call_methods.dart:34:18: Error: Cannot invoke an instance of 'A' because it declares 'call' to be something other than a method.
+ - 'A' is from 'pkg/front_end/testcases/extensions/call_methods.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+var topLevel5 = a(2);
+                 ^";
+static field self::B* b = new self::B::•();
+static field invalid-type topLevel6 = invalid-expression "pkg/front_end/testcases/extensions/call_methods.dart:36:18: Error: Cannot invoke an instance of 'A' because it declares 'call' to be something other than a method.
+ - 'A' is from 'pkg/front_end/testcases/extensions/call_methods.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+var topLevel6 = a(2, \"3\");
+                 ^";
+static method _extension#0|get#call(lowered final core::int* #this) → core::String*
+  return "My name is int";
+static method _extension#1|get#call(lowered final core::num* #this) → core::String*
+  return "My name is num";
+static method _extension#2|get#call(lowered final core::String* #this) → () →* core::String*
+  return () → core::String* => "My name is String";
+static method main() → dynamic {
+  self::_extension#2|get#call("")(){() →* core::String*};
+}
+static method errors() → dynamic {
+  invalid-expression "pkg/front_end/testcases/extensions/call_methods.dart:39:4: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+  1(10);
+   ^" in self::_extension#2|get#call(self::_extension#0|get#call(1)){<inapplicable>}.(10);
+  invalid-expression "pkg/front_end/testcases/extensions/call_methods.dart:40:4: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+  1(\"10\");
+   ^" in self::_extension#2|get#call(self::_extension#0|get#call(1)){<inapplicable>}.("10");
+  invalid-expression "pkg/front_end/testcases/extensions/call_methods.dart:41:6: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+  1.0(10);
+     ^" in self::_extension#2|get#call(self::_extension#1|get#call(1.0)){<inapplicable>}.(10);
+  invalid-expression "pkg/front_end/testcases/extensions/call_methods.dart:42:6: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+  1.0(\"10\");
+     ^" in self::_extension#2|get#call(self::_extension#1|get#call(1.0)){<inapplicable>}.("10");
+  self::A* a = new self::A::•();
+  invalid-expression "pkg/front_end/testcases/extensions/call_methods.dart:44:4: Error: Cannot invoke an instance of 'A' because it declares 'call' to be something other than a method.
+ - 'A' is from 'pkg/front_end/testcases/extensions/call_methods.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+  a(2);
+   ^";
+  invalid-expression "pkg/front_end/testcases/extensions/call_methods.dart:45:4: Error: Cannot invoke an instance of 'A' because it declares 'call' to be something other than a method.
+ - 'A' is from 'pkg/front_end/testcases/extensions/call_methods.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+  a(2, \"3\");
+   ^";
+  self::B* b = new self::B::•();
+  invalid-expression "pkg/front_end/testcases/extensions/call_methods.dart:47:4: Error: Cannot invoke an instance of 'B' because it declares 'call' to be something other than a method.
+ - 'B' is from 'pkg/front_end/testcases/extensions/call_methods.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+  b();
+   ^";
+}
diff --git a/pkg/front_end/testcases/extensions/check_bounds.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/check_bounds.dart.weak.modular.expect
new file mode 100644
index 0000000..0e8aa01
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/check_bounds.dart.weak.modular.expect
@@ -0,0 +1,972 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:24:10: Error: The method 'method' isn't defined for the class 'Class<A>'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'method'.
+//   classA.method(); // Expect method not found.
+//          ^^^^^^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:25:3: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|method'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension(classA).method(); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:26:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|method'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classA).method(); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:28:3: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension(classA).genericMethod(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:28:3: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension(classA).genericMethod(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:29:3: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension(classA).genericMethod<A>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:29:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension(classA).genericMethod<A>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:30:3: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension(classA).genericMethod<B>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:31:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classA).genericMethod(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:31:3: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension<A>(classA).genericMethod(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:32:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classA).genericMethod<A>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:32:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classA).genericMethod<A>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:33:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classA).genericMethod<B>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:34:24: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension<B>(classA).genericMethod(a); // Expect bounds mismatch.
+//                        ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:35:24: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<B>(classA).genericMethod<A>(a); // Expect bounds mismatch.
+//                        ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:41:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|method'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classB).method(); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:44:10: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   classB.genericMethod(a); // Expect bounds mismatch.
+//          ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:45:10: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   classB.genericMethod<A>(a); // Expect bounds mismatch.
+//          ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:47:21: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension(classB).genericMethod(a); // Expect bounds mismatch.
+//                     ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:48:21: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension(classB).genericMethod<A>(a); // Expect bounds mismatch.
+//                     ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:50:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classB).genericMethod(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:50:3: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension<A>(classB).genericMethod(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:51:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classB).genericMethod<A>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:51:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classB).genericMethod<A>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:52:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classB).genericMethod<B>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:53:24: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension<B>(classB).genericMethod(a); // Expect bounds mismatch.
+//                        ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:54:24: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<B>(classB).genericMethod<A>(a); // Expect bounds mismatch.
+//                        ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:60:23: Error: The method 'method' isn't defined for the class 'Class<A>'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'method'.
+// final field1 = classA.method(); // Expect method not found.
+//                       ^^^^^^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:61:16: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|method'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// final field2 = Extension(classA).method(); // Expect bounds mismatch.
+//                ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:62:16: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|method'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// final field3 = Extension<A>(classA).method(); // Expect bounds mismatch.
+//                ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:64:16: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// final field5 = Extension(classA).genericMethod(a); // Expect bounds mismatch.
+//                ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:64:16: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// final field5 = Extension(classA).genericMethod(a); // Expect bounds mismatch.
+//                ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:65:16: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// final field6 = Extension(classA).genericMethod<A>(a); // Expect bounds mismatch.
+//                ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:65:16: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// final field6 = Extension(classA).genericMethod<A>(a); // Expect bounds mismatch.
+//                ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:66:16: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// final field7 = Extension(classA).genericMethod<B>(a); // Expect bounds mismatch.
+//                ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:67:16: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// final field8 = Extension<A>(classA).genericMethod(a); // Expect bounds mismatch.
+//                ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:67:16: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// final field8 = Extension<A>(classA).genericMethod(a); // Expect bounds mismatch.
+//                ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:69:5: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//     Extension<A>(classA).genericMethod<A>(a); // Expect bounds mismatch.
+//     ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:69:5: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//     Extension<A>(classA).genericMethod<A>(a); // Expect bounds mismatch.
+//     ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:71:5: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//     Extension<A>(classA).genericMethod<B>(a); // Expect bounds mismatch.
+//     ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:73:26: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     Extension<B>(classA).genericMethod(a); // Expect bounds mismatch.
+//                          ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:75:26: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//     Extension<B>(classA).genericMethod<A>(a); // Expect bounds mismatch.
+//                          ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:81:17: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|method'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// final field16 = Extension<A>(classB).method(); // Expect bounds mismatch.
+//                 ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:84:24: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// final field18 = classB.genericMethod(a); // Expect bounds mismatch.
+//                        ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:85:24: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// final field19 = classB.genericMethod<A>(a); // Expect bounds mismatch.
+//                        ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:87:35: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// final field21 = Extension(classB).genericMethod(a); // Expect bounds mismatch.
+//                                   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:89:23: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//     Extension(classB).genericMethod<A>(a); // Expect bounds mismatch.
+//                       ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:92:5: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//     Extension<A>(classB).genericMethod(a); // Expect bounds mismatch.
+//     ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:92:5: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     Extension<A>(classB).genericMethod(a); // Expect bounds mismatch.
+//     ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:94:5: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//     Extension<A>(classB).genericMethod<A>(a); // Expect bounds mismatch.
+//     ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:94:5: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//     Extension<A>(classB).genericMethod<A>(a); // Expect bounds mismatch.
+//     ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:96:5: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//     Extension<A>(classB).genericMethod<B>(a); // Expect bounds mismatch.
+//     ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:98:26: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     Extension<B>(classB).genericMethod(a); // Expect bounds mismatch.
+//                          ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds.dart:100:26: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//     Extension<B>(classB).genericMethod<A>(a); // Expect bounds mismatch.
+//                          ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:11:10: Error: The method 'method' isn't defined for the class 'Class<A>'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'method'.
+//   classA.method();
+//          ^^^^^^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:12:3: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|method'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension(classA).method(); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:13:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|method'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classA).method(); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:15:3: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension(classA).genericMethod(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:15:3: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension(classA).genericMethod(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:16:3: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension(classA).genericMethod<A>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:16:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension(classA).genericMethod<A>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:17:3: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension(classA).genericMethod<B>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:18:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classA).genericMethod(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:18:3: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension<A>(classA).genericMethod(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:19:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classA).genericMethod<A>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:19:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classA).genericMethod<A>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:20:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classA).genericMethod<B>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:21:24: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension<B>(classA).genericMethod(a); // Expect bounds mismatch.
+//                        ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:22:24: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<B>(classA).genericMethod<A>(a); // Expect bounds mismatch.
+//                        ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:28:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|method'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classB).method(); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:31:10: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   classB.genericMethod(a); // Expect bounds mismatch.
+//          ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:32:10: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   classB.genericMethod<A>(a); // Expect bounds mismatch.
+//          ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:34:21: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension(classB).genericMethod(a); // Expect bounds mismatch.
+//                     ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:35:21: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension(classB).genericMethod<A>(a); // Expect bounds mismatch.
+//                     ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:37:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classB).genericMethod(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:37:3: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension<A>(classB).genericMethod(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:38:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classB).genericMethod<A>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:38:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classB).genericMethod<A>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:39:3: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'T' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<A>(classB).genericMethod<B>(a); // Expect bounds mismatch.
+//   ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:13:21: Context: This is the type variable whose bound isn't conformed to.
+// extension Extension<T extends B> on Class<T> {
+//                     ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:40:24: Error: Inferred type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   Extension<B>(classB).genericMethod(a); // Expect bounds mismatch.
+//                        ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+// pkg/front_end/testcases/extensions/check_bounds_lib.dart:41:24: Error: Type argument 'A' doesn't conform to the bound 'B' of the type variable 'S' on 'Extension|genericMethod'.
+//  - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   Extension<B>(classB).genericMethod<A>(a); // Expect bounds mismatch.
+//                        ^
+// pkg/front_end/testcases/extensions/check_bounds.dart:15:17: Context: This is the type variable whose bound isn't conformed to.
+//   genericMethod<S extends B>(S s) {}
+//                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+part check_bounds_lib.dart;
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class Class<T extends self::A*> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension<T extends self::B*> on self::Class<T*>* {
+  method method = self::Extension|method;
+  tearoff method = self::Extension|get#method;
+  method genericMethod = self::Extension|genericMethod;
+  tearoff genericMethod = self::Extension|get#genericMethod;
+}
+static final field self::A* a = new self::A::•();
+static final field self::Class<self::A*>* classA = new self::Class::•<self::A*>();
+static final field dynamic field1 = invalid-expression "pkg/front_end/testcases/extensions/check_bounds.dart:60:23: Error: The method 'method' isn't defined for the class 'Class<A>'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+ - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'method'.
+final field1 = classA.method(); // Expect method not found.
+                      ^^^^^^" in self::classA{<unresolved>}.method();
+static final field dynamic field2 = self::Extension|method<self::A*>(self::classA);
+static final field dynamic field3 = self::Extension|method<self::A*>(self::classA);
+static final field dynamic field4 = self::Extension|method<self::B*>(self::classA as{TypeError} self::Class<self::B*>*);
+static final field dynamic field5 = self::Extension|genericMethod<self::A*, self::A*>(self::classA, self::a);
+static final field dynamic field6 = self::Extension|genericMethod<self::A*, self::A*>(self::classA, self::a);
+static final field dynamic field7 = self::Extension|genericMethod<self::A*, self::B*>(self::classA, self::a as{TypeError} self::B*);
+static final field dynamic field8 = self::Extension|genericMethod<self::A*, self::A*>(self::classA, self::a);
+static final field dynamic field9 = self::Extension|genericMethod<self::A*, self::A*>(self::classA, self::a);
+static final field dynamic field10 = self::Extension|genericMethod<self::A*, self::B*>(self::classA, self::a as{TypeError} self::B*);
+static final field dynamic field11 = self::Extension|genericMethod<self::B*, self::A*>(self::classA as{TypeError} self::Class<self::B*>*, self::a);
+static final field dynamic field12 = self::Extension|genericMethod<self::B*, self::A*>(self::classA as{TypeError} self::Class<self::B*>*, self::a);
+static final field dynamic field13 = self::Extension|genericMethod<self::B*, self::B*>(self::classA as{TypeError} self::Class<self::B*>*, self::a as{TypeError} self::B*);
+static final field self::Class<self::B*>* classB = new self::Class::•<self::B*>();
+static final field dynamic field14 = self::Extension|method<self::B*>(self::classB);
+static final field dynamic field15 = self::Extension|method<self::B*>(self::classB);
+static final field dynamic field16 = self::Extension|method<self::A*>(self::classB);
+static final field dynamic field17 = self::Extension|method<self::B*>(self::classB);
+static final field dynamic field18 = self::Extension|genericMethod<self::B*, self::A*>(self::classB, self::a);
+static final field dynamic field19 = self::Extension|genericMethod<self::B*, self::A*>(self::classB, self::a);
+static final field dynamic field20 = self::Extension|genericMethod<self::B*, self::B*>(self::classB, self::a as{TypeError} self::B*);
+static final field dynamic field21 = self::Extension|genericMethod<self::B*, self::A*>(self::classB, self::a);
+static final field dynamic field22 = self::Extension|genericMethod<self::B*, self::A*>(self::classB, self::a);
+static final field dynamic field23 = self::Extension|genericMethod<self::B*, self::B*>(self::classB, self::a as{TypeError} self::B*);
+static final field dynamic field24 = self::Extension|genericMethod<self::A*, self::A*>(self::classB, self::a);
+static final field dynamic field25 = self::Extension|genericMethod<self::A*, self::A*>(self::classB, self::a);
+static final field dynamic field26 = self::Extension|genericMethod<self::A*, self::B*>(self::classB, self::a as{TypeError} self::B*);
+static final field dynamic field27 = self::Extension|genericMethod<self::B*, self::A*>(self::classB, self::a);
+static final field dynamic field28 = self::Extension|genericMethod<self::B*, self::A*>(self::classB, self::a);
+static final field dynamic field29 = self::Extension|genericMethod<self::B*, self::B*>(self::classB, self::a as{TypeError} self::B*);
+static method Extension|method<T extends self::B*>(lowered final self::Class<self::Extension|method::T*>* #this) → dynamic {}
+static method Extension|get#method<T extends self::B*>(lowered final self::Class<self::Extension|get#method::T*>* #this) → () →* dynamic
+  return () → dynamic => self::Extension|method<self::Extension|get#method::T*>(#this);
+static method Extension|genericMethod<T extends self::B*, S extends self::B*>(lowered final self::Class<self::Extension|genericMethod::T*>* #this, self::Extension|genericMethod::S* s) → dynamic {}
+static method Extension|get#genericMethod<T extends self::B*>(lowered final self::Class<self::Extension|get#genericMethod::T*>* #this) → <S extends self::B*>(S*) →* dynamic
+  return <S extends self::B*>(S* s) → dynamic => self::Extension|genericMethod<self::Extension|get#genericMethod::T*, S*>(#this, s);
+static method main() → dynamic {}
+static method test() → dynamic {
+  self::A* a;
+  self::Class<self::A*>* classA = new self::Class::•<self::A*>();
+  invalid-expression "pkg/front_end/testcases/extensions/check_bounds.dart:24:10: Error: The method 'method' isn't defined for the class 'Class<A>'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+ - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'method'.
+  classA.method(); // Expect method not found.
+         ^^^^^^" in classA{<unresolved>}.method();
+  self::Extension|method<self::A*>(classA);
+  self::Extension|method<self::A*>(classA);
+  self::Extension|method<self::B*>(classA as{TypeError} self::Class<self::B*>*);
+  self::Extension|genericMethod<self::A*, self::A*>(classA, a);
+  self::Extension|genericMethod<self::A*, self::A*>(classA, a);
+  self::Extension|genericMethod<self::A*, self::B*>(classA, a as{TypeError} self::B*);
+  self::Extension|genericMethod<self::A*, self::A*>(classA, a);
+  self::Extension|genericMethod<self::A*, self::A*>(classA, a);
+  self::Extension|genericMethod<self::A*, self::B*>(classA, a as{TypeError} self::B*);
+  self::Extension|genericMethod<self::B*, self::A*>(classA as{TypeError} self::Class<self::B*>*, a);
+  self::Extension|genericMethod<self::B*, self::A*>(classA as{TypeError} self::Class<self::B*>*, a);
+  self::Extension|genericMethod<self::B*, self::B*>(classA as{TypeError} self::Class<self::B*>*, a as{TypeError} self::B*);
+  self::Class<self::B*>* classB = new self::Class::•<self::B*>();
+  self::Extension|method<self::B*>(classB);
+  self::Extension|method<self::B*>(classB);
+  self::Extension|method<self::A*>(classB);
+  self::Extension|method<self::B*>(classB);
+  self::Extension|genericMethod<self::B*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::B*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::B*, self::B*>(classB, a as{TypeError} self::B*);
+  self::Extension|genericMethod<self::B*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::B*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::B*, self::B*>(classB, a as{TypeError} self::B*);
+  self::Extension|genericMethod<self::A*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::A*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::A*, self::B*>(classB, a as{TypeError} self::B*);
+  self::Extension|genericMethod<self::B*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::B*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::B*, self::B*>(classB, a as{TypeError} self::B*);
+}
+static method /* from org-dartlang-testcase:///check_bounds_lib.dart */ testInPart() → dynamic {
+  self::A* a;
+  self::Class<self::A*>* classA = new self::Class::•<self::A*>();
+  invalid-expression "pkg/front_end/testcases/extensions/check_bounds_lib.dart:11:10: Error: The method 'method' isn't defined for the class 'Class<A>'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+ - 'A' is from 'pkg/front_end/testcases/extensions/check_bounds.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'method'.
+  classA.method();
+         ^^^^^^" in classA{<unresolved>}.method();
+  self::Extension|method<self::A*>(classA);
+  self::Extension|method<self::A*>(classA);
+  self::Extension|method<self::B*>(classA as{TypeError} self::Class<self::B*>*);
+  self::Extension|genericMethod<self::A*, self::A*>(classA, a);
+  self::Extension|genericMethod<self::A*, self::A*>(classA, a);
+  self::Extension|genericMethod<self::A*, self::B*>(classA, a as{TypeError} self::B*);
+  self::Extension|genericMethod<self::A*, self::A*>(classA, a);
+  self::Extension|genericMethod<self::A*, self::A*>(classA, a);
+  self::Extension|genericMethod<self::A*, self::B*>(classA, a as{TypeError} self::B*);
+  self::Extension|genericMethod<self::B*, self::A*>(classA as{TypeError} self::Class<self::B*>*, a);
+  self::Extension|genericMethod<self::B*, self::A*>(classA as{TypeError} self::Class<self::B*>*, a);
+  self::Extension|genericMethod<self::B*, self::B*>(classA as{TypeError} self::Class<self::B*>*, a as{TypeError} self::B*);
+  self::Class<self::B*>* classB = new self::Class::•<self::B*>();
+  self::Extension|method<self::B*>(classB);
+  self::Extension|method<self::B*>(classB);
+  self::Extension|method<self::A*>(classB);
+  self::Extension|method<self::B*>(classB);
+  self::Extension|genericMethod<self::B*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::B*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::B*, self::B*>(classB, a as{TypeError} self::B*);
+  self::Extension|genericMethod<self::B*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::B*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::B*, self::B*>(classB, a as{TypeError} self::B*);
+  self::Extension|genericMethod<self::A*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::A*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::A*, self::B*>(classB, a as{TypeError} self::B*);
+  self::Extension|genericMethod<self::B*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::B*, self::A*>(classB, a);
+  self::Extension|genericMethod<self::B*, self::B*>(classB, a as{TypeError} self::B*);
+}
diff --git a/pkg/front_end/testcases/extensions/compounds.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/compounds.dart.weak.modular.expect
new file mode 100644
index 0000000..ccd5bd4
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/compounds.dart.weak.modular.expect
@@ -0,0 +1,514 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Number extends core::Object {
+  final field core::int* value;
+  constructor •(core::int* value) → self::Number*
+    : self::Number::value = value, super core::Object::•()
+    ;
+  get hashCode() → core::int*
+    return this.{self::Number::value}{core::int*}.{core::num::hashCode}{core::int*};
+  operator ==(core::Object* other) → core::bool*
+    return other is self::Number* && this.{self::Number::value}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} other{self::Number*}.{self::Number::value}{core::int*};
+  method toString() → core::String*
+    return "Number(${this.{self::Number::value}{core::int*}})";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class extends core::Object {
+  field self::Number* field;
+  constructor •(self::Number* field) → self::Class*
+    : self::Class::field = field, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class IntClass extends core::Object {
+  field core::int* field;
+  constructor •(core::int* field) → self::IntClass*
+    : self::IntClass::field = field, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension NumberExtension on self::Number* {
+  operator + = self::NumberExtension|+;
+  operator - = self::NumberExtension|-;
+}
+extension ClassExtension on self::Class* {
+  get property = self::ClassExtension|get#property;
+  method testImplicitProperties = self::ClassExtension|testImplicitProperties;
+  tearoff testImplicitProperties = self::ClassExtension|get#testImplicitProperties;
+  set property = self::ClassExtension|set#property;
+}
+extension IntClassExtension on self::IntClass* {
+  get property = self::IntClassExtension|get#property;
+  method testImplicitProperties = self::IntClassExtension|testImplicitProperties;
+  tearoff testImplicitProperties = self::IntClassExtension|get#testImplicitProperties;
+  set property = self::IntClassExtension|set#property;
+}
+static method NumberExtension|+(lowered final self::Number* #this, core::Object* other) → self::Number* {
+  if(other is core::int*) {
+    return new self::Number::•(#this.{self::Number::value}{core::int*}.{core::num::+}(other{core::int*}){(core::num*) →* core::int*});
+  }
+  else
+    if(other is self::Number*) {
+      return new self::Number::•(#this.{self::Number::value}{core::int*}.{core::num::+}(other{self::Number*}.{self::Number::value}{core::int*}){(core::num*) →* core::int*});
+    }
+    else {
+      throw new core::ArgumentError::•("${other}");
+    }
+}
+static method NumberExtension|-(lowered final self::Number* #this, core::Object* other) → self::Number* {
+  if(other is core::int*) {
+    return new self::Number::•(#this.{self::Number::value}{core::int*}.{core::num::-}(other{core::int*}){(core::num*) →* core::int*});
+  }
+  else
+    if(other is self::Number*) {
+      return new self::Number::•(#this.{self::Number::value}{core::int*}.{core::num::-}(other{self::Number*}.{self::Number::value}{core::int*}){(core::num*) →* core::int*});
+    }
+    else {
+      throw new core::ArgumentError::•("${other}");
+    }
+}
+static method ClassExtension|get#property(lowered final self::Class* #this) → self::Number*
+  return #this.{self::Class::field}{self::Number*};
+static method ClassExtension|set#property(lowered final self::Class* #this, self::Number* value) → void {
+  #this.{self::Class::field} = value;
+}
+static method ClassExtension|testImplicitProperties(lowered final self::Class* #this) → dynamic {
+  self::Number* n0 = new self::Number::•(0);
+  self::Number* n1 = new self::Number::•(1);
+  self::Number* n2 = new self::Number::•(2);
+  self::expect(n0, self::ClassExtension|get#property(#this));
+  self::expect(n1, let final self::Number* #t1 = self::NumberExtension|+(self::ClassExtension|get#property(#this), n1) in let final void #t2 = self::ClassExtension|set#property(#this, #t1) in #t1);
+  self::expect(n2, let final self::Number* #t3 = self::NumberExtension|+(self::ClassExtension|get#property(#this), n1) in let final void #t4 = self::ClassExtension|set#property(#this, #t3) in #t3);
+  self::expect(n0, let final self::Number* #t5 = self::NumberExtension|-(self::ClassExtension|get#property(#this), n2) in let final void #t6 = self::ClassExtension|set#property(#this, #t5) in #t5);
+  self::expect(n1, let final self::Number* #t7 = self::NumberExtension|+(self::ClassExtension|get#property(#this), n1) in let final void #t8 = self::ClassExtension|set#property(#this, #t7) in #t7);
+  self::expect(n0, let final self::Number* #t9 = self::NumberExtension|-(self::ClassExtension|get#property(#this), n1) in let final void #t10 = self::ClassExtension|set#property(#this, #t9) in #t9);
+  self::expect(n1, let final self::Number* #t11 = self::NumberExtension|+(self::ClassExtension|get#property(#this), 1) in let final void #t12 = self::ClassExtension|set#property(#this, #t11) in #t11);
+  self::expect(n0, let final self::Number* #t13 = self::NumberExtension|-(self::ClassExtension|get#property(#this), 1) in let final void #t14 = self::ClassExtension|set#property(#this, #t13) in #t13);
+  self::expect(n0, let final self::Number* #t15 = self::ClassExtension|get#property(#this) in let final self::Number* #t16 = self::ClassExtension|set#property(#this, self::NumberExtension|+(#t15, 1)) in #t15);
+  self::expect(n1, let final self::Number* #t17 = self::ClassExtension|get#property(#this) in let final self::Number* #t18 = self::ClassExtension|set#property(#this, self::NumberExtension|-(#t17, 1)) in #t17);
+  self::expect(n0, self::ClassExtension|get#property(#this));
+  self::expect(n0, self::ClassExtension|get#property(#this));
+  self::ClassExtension|set#property(#this, self::NumberExtension|+(self::ClassExtension|get#property(#this), n1));
+  self::expect(n1, self::ClassExtension|get#property(#this));
+  self::ClassExtension|set#property(#this, self::NumberExtension|+(self::ClassExtension|get#property(#this), n1));
+  self::expect(n2, self::ClassExtension|get#property(#this));
+  self::ClassExtension|set#property(#this, self::NumberExtension|-(self::ClassExtension|get#property(#this), n2));
+  self::expect(n0, self::ClassExtension|get#property(#this));
+  self::ClassExtension|set#property(#this, self::NumberExtension|+(self::ClassExtension|get#property(#this), n1));
+  self::expect(n1, self::ClassExtension|get#property(#this));
+  self::ClassExtension|set#property(#this, self::NumberExtension|-(self::ClassExtension|get#property(#this), n1));
+  self::expect(n0, self::ClassExtension|get#property(#this));
+  let final self::Number* #t19 = self::NumberExtension|+(self::ClassExtension|get#property(#this), 1) in let final void #t20 = self::ClassExtension|set#property(#this, #t19) in #t19;
+  self::expect(n1, self::ClassExtension|get#property(#this));
+  let final self::Number* #t21 = self::NumberExtension|-(self::ClassExtension|get#property(#this), 1) in let final void #t22 = self::ClassExtension|set#property(#this, #t21) in #t21;
+  self::expect(n0, self::ClassExtension|get#property(#this));
+  self::ClassExtension|set#property(#this, self::NumberExtension|+(self::ClassExtension|get#property(#this), 1));
+  self::expect(n1, self::ClassExtension|get#property(#this));
+  self::ClassExtension|set#property(#this, self::NumberExtension|-(self::ClassExtension|get#property(#this), 1));
+  self::expect(n0, self::ClassExtension|get#property(#this));
+}
+static method ClassExtension|get#testImplicitProperties(lowered final self::Class* #this) → () →* dynamic
+  return () → dynamic => self::ClassExtension|testImplicitProperties(#this);
+static method IntClassExtension|get#property(lowered final self::IntClass* #this) → core::int*
+  return #this.{self::IntClass::field}{core::int*};
+static method IntClassExtension|set#property(lowered final self::IntClass* #this, core::int* value) → void {
+  #this.{self::IntClass::field} = value;
+}
+static method IntClassExtension|testImplicitProperties(lowered final self::IntClass* #this) → dynamic {
+  core::int* n0 = 0;
+  core::int* n1 = 1;
+  core::int* n2 = 2;
+  self::expect(n0, self::IntClassExtension|get#property(#this));
+  self::expect(n1, let final core::int* #t23 = self::IntClassExtension|get#property(#this).{core::num::+}(n1){(core::num*) →* core::int*} in let final void #t24 = self::IntClassExtension|set#property(#this, #t23) in #t23);
+  self::expect(n2, let final core::int* #t25 = self::IntClassExtension|get#property(#this).{core::num::+}(n1){(core::num*) →* core::int*} in let final void #t26 = self::IntClassExtension|set#property(#this, #t25) in #t25);
+  self::expect(n0, let final core::int* #t27 = self::IntClassExtension|get#property(#this).{core::num::-}(n2){(core::num*) →* core::int*} in let final void #t28 = self::IntClassExtension|set#property(#this, #t27) in #t27);
+  self::expect(n1, let final core::int* #t29 = self::IntClassExtension|get#property(#this).{core::num::+}(n1){(core::num*) →* core::int*} in let final void #t30 = self::IntClassExtension|set#property(#this, #t29) in #t29);
+  self::expect(n0, let final core::int* #t31 = self::IntClassExtension|get#property(#this).{core::num::-}(n1){(core::num*) →* core::int*} in let final void #t32 = self::IntClassExtension|set#property(#this, #t31) in #t31);
+  self::expect(n1, let final core::int* #t33 = self::IntClassExtension|get#property(#this).{core::num::+}(1){(core::num*) →* core::int*} in let final void #t34 = self::IntClassExtension|set#property(#this, #t33) in #t33);
+  self::expect(n0, let final core::int* #t35 = self::IntClassExtension|get#property(#this).{core::num::-}(1){(core::num*) →* core::int*} in let final void #t36 = self::IntClassExtension|set#property(#this, #t35) in #t35);
+  self::expect(n0, let final core::int* #t37 = self::IntClassExtension|get#property(#this) in let final core::int* #t38 = self::IntClassExtension|set#property(#this, #t37.{core::num::+}(1){(core::num*) →* core::int*}) in #t37);
+  self::expect(n1, let final core::int* #t39 = self::IntClassExtension|get#property(#this) in let final core::int* #t40 = self::IntClassExtension|set#property(#this, #t39.{core::num::-}(1){(core::num*) →* core::int*}) in #t39);
+  self::expect(n0, self::IntClassExtension|get#property(#this));
+  self::expect(n0, self::IntClassExtension|get#property(#this));
+  self::IntClassExtension|set#property(#this, self::IntClassExtension|get#property(#this).{core::num::+}(n1){(core::num*) →* core::int*});
+  self::expect(n1, self::IntClassExtension|get#property(#this));
+  self::IntClassExtension|set#property(#this, self::IntClassExtension|get#property(#this).{core::num::+}(n1){(core::num*) →* core::int*});
+  self::expect(n2, self::IntClassExtension|get#property(#this));
+  self::IntClassExtension|set#property(#this, self::IntClassExtension|get#property(#this).{core::num::-}(n2){(core::num*) →* core::int*});
+  self::expect(n0, self::IntClassExtension|get#property(#this));
+  self::IntClassExtension|set#property(#this, self::IntClassExtension|get#property(#this).{core::num::+}(n1){(core::num*) →* core::int*});
+  self::expect(n1, self::IntClassExtension|get#property(#this));
+  self::IntClassExtension|set#property(#this, self::IntClassExtension|get#property(#this).{core::num::-}(n1){(core::num*) →* core::int*});
+  self::expect(n0, self::IntClassExtension|get#property(#this));
+  let final core::int* #t41 = self::IntClassExtension|get#property(#this).{core::num::+}(1){(core::num*) →* core::int*} in let final void #t42 = self::IntClassExtension|set#property(#this, #t41) in #t41;
+  self::expect(n1, self::IntClassExtension|get#property(#this));
+  let final core::int* #t43 = self::IntClassExtension|get#property(#this).{core::num::-}(1){(core::num*) →* core::int*} in let final void #t44 = self::IntClassExtension|set#property(#this, #t43) in #t43;
+  self::expect(n0, self::IntClassExtension|get#property(#this));
+  self::IntClassExtension|set#property(#this, self::IntClassExtension|get#property(#this).{core::num::+}(1){(core::num*) →* core::int*});
+  self::expect(n1, self::IntClassExtension|get#property(#this));
+  self::IntClassExtension|set#property(#this, self::IntClassExtension|get#property(#this).{core::num::-}(1){(core::num*) →* core::int*});
+  self::expect(n0, self::IntClassExtension|get#property(#this));
+}
+static method IntClassExtension|get#testImplicitProperties(lowered final self::IntClass* #this) → () →* dynamic
+  return () → dynamic => self::IntClassExtension|testImplicitProperties(#this);
+static method main() → dynamic {
+  self::testLocals();
+  self::testProperties();
+  self::testIntProperties();
+  self::testExplicitProperties();
+  self::testExplicitIntProperties();
+  self::testExplicitNullAwareProperties(null);
+  self::testExplicitNullAwareProperties(new self::Class::•(new self::Number::•(0)));
+  self::testExplicitNullAwareIntProperties(null);
+  self::testExplicitNullAwareIntProperties(new self::IntClass::•(0));
+  self::ClassExtension|testImplicitProperties(new self::Class::•(new self::Number::•(0)));
+  self::IntClassExtension|testImplicitProperties(new self::IntClass::•(0));
+}
+static method testLocals() → dynamic {
+  self::Number* n0 = new self::Number::•(0);
+  self::Number* n1 = new self::Number::•(1);
+  self::Number* n2 = new self::Number::•(2);
+  self::Number* v = n0;
+  self::expect(n0, v);
+  self::expect(n1, v = self::NumberExtension|+(v, n1));
+  self::expect(n2, v = self::NumberExtension|+(v, n1));
+  self::expect(n0, v = self::NumberExtension|-(v, n2));
+  self::expect(n1, v = self::NumberExtension|+(v, n1));
+  self::expect(n0, v = self::NumberExtension|-(v, n1));
+  self::expect(n1, v = self::NumberExtension|+(v, 1));
+  self::expect(n0, v = self::NumberExtension|-(v, 1));
+  self::expect(n0, let final self::Number* #t45 = v in let final self::Number* #t46 = v = self::NumberExtension|+(#t45, 1) in #t45);
+  self::expect(n1, let final self::Number* #t47 = v in let final self::Number* #t48 = v = self::NumberExtension|-(#t47, 1) in #t47);
+  self::expect(n0, v);
+  self::expect(n0, v);
+  v = self::NumberExtension|+(v, n1);
+  self::expect(n1, v);
+  v = self::NumberExtension|+(v, n1);
+  self::expect(n2, v);
+  v = self::NumberExtension|-(v, n2);
+  self::expect(n0, v);
+  v = self::NumberExtension|+(v, n1);
+  self::expect(n1, v);
+  v = self::NumberExtension|-(v, n1);
+  self::expect(n0, v);
+  v = self::NumberExtension|+(v, 1);
+  self::expect(n1, v);
+  v = self::NumberExtension|-(v, 1);
+  self::expect(n0, v);
+  v = self::NumberExtension|+(v, 1);
+  self::expect(n1, v);
+  v = self::NumberExtension|-(v, 1);
+  self::expect(n0, v);
+}
+static method testProperties() → dynamic {
+  self::Number* n0 = new self::Number::•(0);
+  self::Number* n1 = new self::Number::•(1);
+  self::Number* n2 = new self::Number::•(2);
+  self::Class* v = new self::Class::•(n0);
+  self::expect(n0, v.{self::Class::field}{self::Number*});
+  self::expect(n1, let final self::Class* #t49 = v in #t49.{self::Class::field} = self::NumberExtension|+(#t49.{self::Class::field}{self::Number*}, n1));
+  self::expect(n2, let final self::Class* #t50 = v in #t50.{self::Class::field} = self::NumberExtension|+(#t50.{self::Class::field}{self::Number*}, n1));
+  self::expect(n0, let final self::Class* #t51 = v in #t51.{self::Class::field} = self::NumberExtension|-(#t51.{self::Class::field}{self::Number*}, n2));
+  self::expect(n1, let final self::Class* #t52 = v in #t52.{self::Class::field} = self::NumberExtension|+(#t52.{self::Class::field}{self::Number*}, n1));
+  self::expect(n0, let final self::Class* #t53 = v in #t53.{self::Class::field} = self::NumberExtension|-(#t53.{self::Class::field}{self::Number*}, n1));
+  self::expect(n1, let final self::Class* #t54 = v in #t54.{self::Class::field} = self::NumberExtension|+(#t54.{self::Class::field}{self::Number*}, 1));
+  self::expect(n0, let final self::Class* #t55 = v in #t55.{self::Class::field} = self::NumberExtension|-(#t55.{self::Class::field}{self::Number*}, 1));
+  self::expect(n0, let final self::Class* #t56 = v in let final self::Number* #t57 = #t56.{self::Class::field}{self::Number*} in let final self::Number* #t58 = #t56.{self::Class::field} = self::NumberExtension|+(#t57, 1) in #t57);
+  self::expect(n1, let final self::Class* #t59 = v in let final self::Number* #t60 = #t59.{self::Class::field}{self::Number*} in let final self::Number* #t61 = #t59.{self::Class::field} = self::NumberExtension|-(#t60, 1) in #t60);
+  self::expect(n0, v.{self::Class::field}{self::Number*});
+  self::expect(n0, v.{self::Class::field}{self::Number*});
+  let final self::Class* #t62 = v in #t62.{self::Class::field} = self::NumberExtension|+(#t62.{self::Class::field}{self::Number*}, n1);
+  self::expect(n1, v.{self::Class::field}{self::Number*});
+  let final self::Class* #t63 = v in #t63.{self::Class::field} = self::NumberExtension|+(#t63.{self::Class::field}{self::Number*}, n1);
+  self::expect(n2, v.{self::Class::field}{self::Number*});
+  let final self::Class* #t64 = v in #t64.{self::Class::field} = self::NumberExtension|-(#t64.{self::Class::field}{self::Number*}, n2);
+  self::expect(n0, v.{self::Class::field}{self::Number*});
+  let final self::Class* #t65 = v in #t65.{self::Class::field} = self::NumberExtension|+(#t65.{self::Class::field}{self::Number*}, n1);
+  self::expect(n1, v.{self::Class::field}{self::Number*});
+  let final self::Class* #t66 = v in #t66.{self::Class::field} = self::NumberExtension|-(#t66.{self::Class::field}{self::Number*}, n1);
+  self::expect(n0, v.{self::Class::field}{self::Number*});
+  let final self::Class* #t67 = v in #t67.{self::Class::field} = self::NumberExtension|+(#t67.{self::Class::field}{self::Number*}, 1);
+  self::expect(n1, v.{self::Class::field}{self::Number*});
+  let final self::Class* #t68 = v in #t68.{self::Class::field} = self::NumberExtension|-(#t68.{self::Class::field}{self::Number*}, 1);
+  self::expect(n0, v.{self::Class::field}{self::Number*});
+  let final self::Class* #t69 = v in #t69.{self::Class::field} = self::NumberExtension|+(#t69.{self::Class::field}{self::Number*}, 1);
+  self::expect(n1, v.{self::Class::field}{self::Number*});
+  let final self::Class* #t70 = v in #t70.{self::Class::field} = self::NumberExtension|-(#t70.{self::Class::field}{self::Number*}, 1);
+  self::expect(n0, v.{self::Class::field}{self::Number*});
+  self::expect(n0, self::ClassExtension|get#property(v));
+  self::expect(n1, let final self::Class* #t71 = v in let final self::Number* #t72 = self::NumberExtension|+(self::ClassExtension|get#property(#t71), n1) in let final void #t73 = self::ClassExtension|set#property(#t71, #t72) in #t72);
+  self::expect(n2, let final self::Class* #t74 = v in let final self::Number* #t75 = self::NumberExtension|+(self::ClassExtension|get#property(#t74), n1) in let final void #t76 = self::ClassExtension|set#property(#t74, #t75) in #t75);
+  self::expect(n0, let final self::Class* #t77 = v in let final self::Number* #t78 = self::NumberExtension|-(self::ClassExtension|get#property(#t77), n2) in let final void #t79 = self::ClassExtension|set#property(#t77, #t78) in #t78);
+  self::expect(n1, let final self::Class* #t80 = v in let final self::Number* #t81 = self::NumberExtension|+(self::ClassExtension|get#property(#t80), n1) in let final void #t82 = self::ClassExtension|set#property(#t80, #t81) in #t81);
+  self::expect(n0, let final self::Class* #t83 = v in let final self::Number* #t84 = self::NumberExtension|-(self::ClassExtension|get#property(#t83), n1) in let final void #t85 = self::ClassExtension|set#property(#t83, #t84) in #t84);
+  self::expect(n1, let final self::Class* #t86 = v in let final self::Number* #t87 = self::NumberExtension|+(self::ClassExtension|get#property(#t86), 1) in let final void #t88 = self::ClassExtension|set#property(#t86, #t87) in #t87);
+  self::expect(n0, let final self::Class* #t89 = v in let final self::Number* #t90 = self::NumberExtension|-(self::ClassExtension|get#property(#t89), 1) in let final void #t91 = self::ClassExtension|set#property(#t89, #t90) in #t90);
+  self::expect(n0, let final self::Class* #t92 = v in let final self::Number* #t93 = self::ClassExtension|get#property(#t92) in let final self::Number* #t94 = self::ClassExtension|set#property(#t92, self::NumberExtension|+(#t93, 1)) in #t93);
+  self::expect(n1, let final self::Class* #t95 = v in let final self::Number* #t96 = self::ClassExtension|get#property(#t95) in let final self::Number* #t97 = self::ClassExtension|set#property(#t95, self::NumberExtension|-(#t96, 1)) in #t96);
+  self::expect(n0, self::ClassExtension|get#property(v));
+  self::expect(n0, self::ClassExtension|get#property(v));
+  let final self::Class* #t98 = v in self::ClassExtension|set#property(#t98, self::NumberExtension|+(self::ClassExtension|get#property(#t98), n1));
+  self::expect(n1, self::ClassExtension|get#property(v));
+  let final self::Class* #t99 = v in self::ClassExtension|set#property(#t99, self::NumberExtension|+(self::ClassExtension|get#property(#t99), n1));
+  self::expect(n2, self::ClassExtension|get#property(v));
+  let final self::Class* #t100 = v in self::ClassExtension|set#property(#t100, self::NumberExtension|-(self::ClassExtension|get#property(#t100), n2));
+  self::expect(n0, self::ClassExtension|get#property(v));
+  let final self::Class* #t101 = v in self::ClassExtension|set#property(#t101, self::NumberExtension|+(self::ClassExtension|get#property(#t101), n1));
+  self::expect(n1, self::ClassExtension|get#property(v));
+  let final self::Class* #t102 = v in self::ClassExtension|set#property(#t102, self::NumberExtension|-(self::ClassExtension|get#property(#t102), n1));
+  self::expect(n0, self::ClassExtension|get#property(v));
+  let final self::Class* #t103 = v in let final self::Number* #t104 = self::NumberExtension|+(self::ClassExtension|get#property(#t103), 1) in let final void #t105 = self::ClassExtension|set#property(#t103, #t104) in #t104;
+  self::expect(n1, self::ClassExtension|get#property(v));
+  let final self::Class* #t106 = v in let final self::Number* #t107 = self::NumberExtension|-(self::ClassExtension|get#property(#t106), 1) in let final void #t108 = self::ClassExtension|set#property(#t106, #t107) in #t107;
+  self::expect(n0, self::ClassExtension|get#property(v));
+  let final self::Class* #t109 = v in self::ClassExtension|set#property(#t109, self::NumberExtension|+(self::ClassExtension|get#property(#t109), 1));
+  self::expect(n1, self::ClassExtension|get#property(v));
+  let final self::Class* #t110 = v in self::ClassExtension|set#property(#t110, self::NumberExtension|-(self::ClassExtension|get#property(#t110), 1));
+  self::expect(n0, self::ClassExtension|get#property(v));
+}
+static method testIntProperties() → dynamic {
+  core::int* n0 = 0;
+  core::int* n1 = 1;
+  core::int* n2 = 2;
+  self::IntClass* v = new self::IntClass::•(n0);
+  self::expect(n0, v.{self::IntClass::field}{core::int*});
+  self::expect(n1, let final self::IntClass* #t111 = v in #t111.{self::IntClass::field} = #t111.{self::IntClass::field}{core::int*}.{core::num::+}(n1){(core::num*) →* core::int*});
+  self::expect(n2, let final self::IntClass* #t112 = v in #t112.{self::IntClass::field} = #t112.{self::IntClass::field}{core::int*}.{core::num::+}(n1){(core::num*) →* core::int*});
+  self::expect(n0, let final self::IntClass* #t113 = v in #t113.{self::IntClass::field} = #t113.{self::IntClass::field}{core::int*}.{core::num::-}(n2){(core::num*) →* core::int*});
+  self::expect(n1, let final self::IntClass* #t114 = v in #t114.{self::IntClass::field} = #t114.{self::IntClass::field}{core::int*}.{core::num::+}(n1){(core::num*) →* core::int*});
+  self::expect(n0, let final self::IntClass* #t115 = v in #t115.{self::IntClass::field} = #t115.{self::IntClass::field}{core::int*}.{core::num::-}(n1){(core::num*) →* core::int*});
+  self::expect(n1, let final self::IntClass* #t116 = v in #t116.{self::IntClass::field} = #t116.{self::IntClass::field}{core::int*}.{core::num::+}(1){(core::num*) →* core::int*});
+  self::expect(n0, let final self::IntClass* #t117 = v in #t117.{self::IntClass::field} = #t117.{self::IntClass::field}{core::int*}.{core::num::-}(1){(core::num*) →* core::int*});
+  self::expect(n0, let final self::IntClass* #t118 = v in let final core::int* #t119 = #t118.{self::IntClass::field}{core::int*} in let final core::int* #t120 = #t118.{self::IntClass::field} = #t119.{core::num::+}(1){(core::num*) →* core::int*} in #t119);
+  self::expect(n1, let final self::IntClass* #t121 = v in let final core::int* #t122 = #t121.{self::IntClass::field}{core::int*} in let final core::int* #t123 = #t121.{self::IntClass::field} = #t122.{core::num::-}(1){(core::num*) →* core::int*} in #t122);
+  self::expect(n0, v.{self::IntClass::field}{core::int*});
+  self::expect(n0, v.{self::IntClass::field}{core::int*});
+  let final self::IntClass* #t124 = v in #t124.{self::IntClass::field} = #t124.{self::IntClass::field}{core::int*}.{core::num::+}(n1){(core::num*) →* core::int*};
+  self::expect(n1, v.{self::IntClass::field}{core::int*});
+  let final self::IntClass* #t125 = v in #t125.{self::IntClass::field} = #t125.{self::IntClass::field}{core::int*}.{core::num::+}(n1){(core::num*) →* core::int*};
+  self::expect(n2, v.{self::IntClass::field}{core::int*});
+  let final self::IntClass* #t126 = v in #t126.{self::IntClass::field} = #t126.{self::IntClass::field}{core::int*}.{core::num::-}(n2){(core::num*) →* core::int*};
+  self::expect(n0, v.{self::IntClass::field}{core::int*});
+  let final self::IntClass* #t127 = v in #t127.{self::IntClass::field} = #t127.{self::IntClass::field}{core::int*}.{core::num::+}(n1){(core::num*) →* core::int*};
+  self::expect(n1, v.{self::IntClass::field}{core::int*});
+  let final self::IntClass* #t128 = v in #t128.{self::IntClass::field} = #t128.{self::IntClass::field}{core::int*}.{core::num::-}(n1){(core::num*) →* core::int*};
+  self::expect(n0, v.{self::IntClass::field}{core::int*});
+  let final self::IntClass* #t129 = v in #t129.{self::IntClass::field} = #t129.{self::IntClass::field}{core::int*}.{core::num::+}(1){(core::num*) →* core::int*};
+  self::expect(n1, v.{self::IntClass::field}{core::int*});
+  let final self::IntClass* #t130 = v in #t130.{self::IntClass::field} = #t130.{self::IntClass::field}{core::int*}.{core::num::-}(1){(core::num*) →* core::int*};
+  self::expect(n0, v.{self::IntClass::field}{core::int*});
+  let final self::IntClass* #t131 = v in #t131.{self::IntClass::field} = #t131.{self::IntClass::field}{core::int*}.{core::num::+}(1){(core::num*) →* core::int*};
+  self::expect(n1, v.{self::IntClass::field}{core::int*});
+  let final self::IntClass* #t132 = v in #t132.{self::IntClass::field} = #t132.{self::IntClass::field}{core::int*}.{core::num::-}(1){(core::num*) →* core::int*};
+  self::expect(n0, v.{self::IntClass::field}{core::int*});
+  self::expect(n0, self::IntClassExtension|get#property(v));
+  self::expect(n1, let final self::IntClass* #t133 = v in let final core::int* #t134 = self::IntClassExtension|get#property(#t133).{core::num::+}(n1){(core::num*) →* core::int*} in let final void #t135 = self::IntClassExtension|set#property(#t133, #t134) in #t134);
+  self::expect(n2, let final self::IntClass* #t136 = v in let final core::int* #t137 = self::IntClassExtension|get#property(#t136).{core::num::+}(n1){(core::num*) →* core::int*} in let final void #t138 = self::IntClassExtension|set#property(#t136, #t137) in #t137);
+  self::expect(n0, let final self::IntClass* #t139 = v in let final core::int* #t140 = self::IntClassExtension|get#property(#t139).{core::num::-}(n2){(core::num*) →* core::int*} in let final void #t141 = self::IntClassExtension|set#property(#t139, #t140) in #t140);
+  self::expect(n1, let final self::IntClass* #t142 = v in let final core::int* #t143 = self::IntClassExtension|get#property(#t142).{core::num::+}(n1){(core::num*) →* core::int*} in let final void #t144 = self::IntClassExtension|set#property(#t142, #t143) in #t143);
+  self::expect(n0, let final self::IntClass* #t145 = v in let final core::int* #t146 = self::IntClassExtension|get#property(#t145).{core::num::-}(n1){(core::num*) →* core::int*} in let final void #t147 = self::IntClassExtension|set#property(#t145, #t146) in #t146);
+  self::expect(n1, let final self::IntClass* #t148 = v in let final core::int* #t149 = self::IntClassExtension|get#property(#t148).{core::num::+}(1){(core::num*) →* core::int*} in let final void #t150 = self::IntClassExtension|set#property(#t148, #t149) in #t149);
+  self::expect(n0, let final self::IntClass* #t151 = v in let final core::int* #t152 = self::IntClassExtension|get#property(#t151).{core::num::-}(1){(core::num*) →* core::int*} in let final void #t153 = self::IntClassExtension|set#property(#t151, #t152) in #t152);
+  self::expect(n0, let final self::IntClass* #t154 = v in let final core::int* #t155 = self::IntClassExtension|get#property(#t154) in let final core::int* #t156 = self::IntClassExtension|set#property(#t154, #t155.{core::num::+}(1){(core::num*) →* core::int*}) in #t155);
+  self::expect(n1, let final self::IntClass* #t157 = v in let final core::int* #t158 = self::IntClassExtension|get#property(#t157) in let final core::int* #t159 = self::IntClassExtension|set#property(#t157, #t158.{core::num::-}(1){(core::num*) →* core::int*}) in #t158);
+  self::expect(n0, self::IntClassExtension|get#property(v));
+  self::expect(n0, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t160 = v in self::IntClassExtension|set#property(#t160, self::IntClassExtension|get#property(#t160).{core::num::+}(n1){(core::num*) →* core::int*});
+  self::expect(n1, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t161 = v in self::IntClassExtension|set#property(#t161, self::IntClassExtension|get#property(#t161).{core::num::+}(n1){(core::num*) →* core::int*});
+  self::expect(n2, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t162 = v in self::IntClassExtension|set#property(#t162, self::IntClassExtension|get#property(#t162).{core::num::-}(n2){(core::num*) →* core::int*});
+  self::expect(n0, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t163 = v in self::IntClassExtension|set#property(#t163, self::IntClassExtension|get#property(#t163).{core::num::+}(n1){(core::num*) →* core::int*});
+  self::expect(n1, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t164 = v in self::IntClassExtension|set#property(#t164, self::IntClassExtension|get#property(#t164).{core::num::-}(n1){(core::num*) →* core::int*});
+  self::expect(n0, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t165 = v in let final core::int* #t166 = self::IntClassExtension|get#property(#t165).{core::num::+}(1){(core::num*) →* core::int*} in let final void #t167 = self::IntClassExtension|set#property(#t165, #t166) in #t166;
+  self::expect(n1, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t168 = v in let final core::int* #t169 = self::IntClassExtension|get#property(#t168).{core::num::-}(1){(core::num*) →* core::int*} in let final void #t170 = self::IntClassExtension|set#property(#t168, #t169) in #t169;
+  self::expect(n0, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t171 = v in self::IntClassExtension|set#property(#t171, self::IntClassExtension|get#property(#t171).{core::num::+}(1){(core::num*) →* core::int*});
+  self::expect(n1, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t172 = v in self::IntClassExtension|set#property(#t172, self::IntClassExtension|get#property(#t172).{core::num::-}(1){(core::num*) →* core::int*});
+  self::expect(n0, self::IntClassExtension|get#property(v));
+}
+static method testExplicitProperties() → dynamic {
+  self::Number* n0 = new self::Number::•(0);
+  self::Number* n1 = new self::Number::•(1);
+  self::Number* n2 = new self::Number::•(2);
+  self::Class* v = new self::Class::•(n0);
+  self::expect(n0, self::ClassExtension|get#property(v));
+  self::expect(n1, let final self::Class* #t173 = v in let final self::Number* #t174 = self::NumberExtension|+(self::ClassExtension|get#property(#t173), n1) in let final void #t175 = self::ClassExtension|set#property(#t173, #t174) in #t174);
+  self::expect(n2, let final self::Class* #t176 = v in let final self::Number* #t177 = self::NumberExtension|+(self::ClassExtension|get#property(#t176), n1) in let final void #t178 = self::ClassExtension|set#property(#t176, #t177) in #t177);
+  self::expect(n0, let final self::Class* #t179 = v in let final self::Number* #t180 = self::NumberExtension|-(self::ClassExtension|get#property(#t179), n2) in let final void #t181 = self::ClassExtension|set#property(#t179, #t180) in #t180);
+  self::expect(n1, let final self::Class* #t182 = v in let final self::Number* #t183 = self::NumberExtension|+(self::ClassExtension|get#property(#t182), n1) in let final void #t184 = self::ClassExtension|set#property(#t182, #t183) in #t183);
+  self::expect(n0, let final self::Class* #t185 = v in let final self::Number* #t186 = self::NumberExtension|-(self::ClassExtension|get#property(#t185), n1) in let final void #t187 = self::ClassExtension|set#property(#t185, #t186) in #t186);
+  self::expect(n1, let final self::Class* #t188 = v in let final self::Number* #t189 = self::NumberExtension|+(self::ClassExtension|get#property(#t188), 1) in let final void #t190 = self::ClassExtension|set#property(#t188, #t189) in #t189);
+  self::expect(n0, let final self::Class* #t191 = v in let final self::Number* #t192 = self::NumberExtension|-(self::ClassExtension|get#property(#t191), 1) in let final void #t193 = self::ClassExtension|set#property(#t191, #t192) in #t192);
+  self::expect(n0, let final self::Class* #t194 = v in let final self::Number* #t195 = self::ClassExtension|get#property(#t194) in let final self::Number* #t196 = let final self::Number* #t197 = self::NumberExtension|+(#t195, 1) in let final void #t198 = self::ClassExtension|set#property(#t194, #t197) in #t197 in #t195);
+  self::expect(n1, let final self::Class* #t199 = v in let final self::Number* #t200 = self::ClassExtension|get#property(#t199) in let final self::Number* #t201 = let final self::Number* #t202 = self::NumberExtension|-(#t200, 1) in let final void #t203 = self::ClassExtension|set#property(#t199, #t202) in #t202 in #t200);
+  self::expect(n0, self::ClassExtension|get#property(v));
+  self::expect(n0, self::ClassExtension|get#property(v));
+  let final self::Class* #t204 = v in self::ClassExtension|set#property(#t204, self::NumberExtension|+(self::ClassExtension|get#property(#t204), n1));
+  self::expect(n1, self::ClassExtension|get#property(v));
+  let final self::Class* #t205 = v in self::ClassExtension|set#property(#t205, self::NumberExtension|+(self::ClassExtension|get#property(#t205), n1));
+  self::expect(n2, self::ClassExtension|get#property(v));
+  let final self::Class* #t206 = v in self::ClassExtension|set#property(#t206, self::NumberExtension|-(self::ClassExtension|get#property(#t206), n2));
+  self::expect(n0, self::ClassExtension|get#property(v));
+  let final self::Class* #t207 = v in self::ClassExtension|set#property(#t207, self::NumberExtension|+(self::ClassExtension|get#property(#t207), n1));
+  self::expect(n1, self::ClassExtension|get#property(v));
+  let final self::Class* #t208 = v in self::ClassExtension|set#property(#t208, self::NumberExtension|-(self::ClassExtension|get#property(#t208), n1));
+  self::expect(n0, self::ClassExtension|get#property(v));
+  let final self::Class* #t209 = v in let final self::Number* #t210 = self::NumberExtension|+(self::ClassExtension|get#property(#t209), 1) in let final void #t211 = self::ClassExtension|set#property(#t209, #t210) in #t210;
+  self::expect(n1, self::ClassExtension|get#property(v));
+  let final self::Class* #t212 = v in let final self::Number* #t213 = self::NumberExtension|-(self::ClassExtension|get#property(#t212), 1) in let final void #t214 = self::ClassExtension|set#property(#t212, #t213) in #t213;
+  self::expect(n0, self::ClassExtension|get#property(v));
+  let final self::Class* #t215 = v in self::ClassExtension|set#property(#t215, self::NumberExtension|+(self::ClassExtension|get#property(#t215), 1));
+  self::expect(n1, self::ClassExtension|get#property(v));
+  let final self::Class* #t216 = v in self::ClassExtension|set#property(#t216, self::NumberExtension|-(self::ClassExtension|get#property(#t216), 1));
+  self::expect(n0, self::ClassExtension|get#property(v));
+}
+static method testExplicitIntProperties() → dynamic {
+  core::int* n0 = 0;
+  core::int* n1 = 1;
+  core::int* n2 = 2;
+  self::IntClass* v = new self::IntClass::•(n0);
+  self::expect(n0, self::IntClassExtension|get#property(v));
+  self::expect(n1, let final self::IntClass* #t217 = v in let final core::int* #t218 = self::IntClassExtension|get#property(#t217).{core::num::+}(n1){(core::num*) →* core::int*} in let final void #t219 = self::IntClassExtension|set#property(#t217, #t218) in #t218);
+  self::expect(n2, let final self::IntClass* #t220 = v in let final core::int* #t221 = self::IntClassExtension|get#property(#t220).{core::num::+}(n1){(core::num*) →* core::int*} in let final void #t222 = self::IntClassExtension|set#property(#t220, #t221) in #t221);
+  self::expect(n0, let final self::IntClass* #t223 = v in let final core::int* #t224 = self::IntClassExtension|get#property(#t223).{core::num::-}(n2){(core::num*) →* core::int*} in let final void #t225 = self::IntClassExtension|set#property(#t223, #t224) in #t224);
+  self::expect(n1, let final self::IntClass* #t226 = v in let final core::int* #t227 = self::IntClassExtension|get#property(#t226).{core::num::+}(n1){(core::num*) →* core::int*} in let final void #t228 = self::IntClassExtension|set#property(#t226, #t227) in #t227);
+  self::expect(n0, let final self::IntClass* #t229 = v in let final core::int* #t230 = self::IntClassExtension|get#property(#t229).{core::num::-}(n1){(core::num*) →* core::int*} in let final void #t231 = self::IntClassExtension|set#property(#t229, #t230) in #t230);
+  self::expect(n1, let final self::IntClass* #t232 = v in let final core::int* #t233 = self::IntClassExtension|get#property(#t232).{core::num::+}(1){(core::num*) →* core::int*} in let final void #t234 = self::IntClassExtension|set#property(#t232, #t233) in #t233);
+  self::expect(n0, let final self::IntClass* #t235 = v in let final core::int* #t236 = self::IntClassExtension|get#property(#t235).{core::num::-}(1){(core::num*) →* core::int*} in let final void #t237 = self::IntClassExtension|set#property(#t235, #t236) in #t236);
+  self::expect(n0, let final self::IntClass* #t238 = v in let final core::int* #t239 = self::IntClassExtension|get#property(#t238) in let final core::int* #t240 = let final core::int* #t241 = #t239.{core::num::+}(1){(core::num*) →* core::int*} in let final void #t242 = self::IntClassExtension|set#property(#t238, #t241) in #t241 in #t239);
+  self::expect(n1, let final self::IntClass* #t243 = v in let final core::int* #t244 = self::IntClassExtension|get#property(#t243) in let final core::int* #t245 = let final core::int* #t246 = #t244.{core::num::-}(1){(core::num*) →* core::int*} in let final void #t247 = self::IntClassExtension|set#property(#t243, #t246) in #t246 in #t244);
+  self::expect(n0, self::IntClassExtension|get#property(v));
+  self::expect(n0, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t248 = v in self::IntClassExtension|set#property(#t248, self::IntClassExtension|get#property(#t248).{core::num::+}(n1){(core::num*) →* core::int*});
+  self::expect(n1, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t249 = v in self::IntClassExtension|set#property(#t249, self::IntClassExtension|get#property(#t249).{core::num::+}(n1){(core::num*) →* core::int*});
+  self::expect(n2, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t250 = v in self::IntClassExtension|set#property(#t250, self::IntClassExtension|get#property(#t250).{core::num::-}(n2){(core::num*) →* core::int*});
+  self::expect(n0, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t251 = v in self::IntClassExtension|set#property(#t251, self::IntClassExtension|get#property(#t251).{core::num::+}(n1){(core::num*) →* core::int*});
+  self::expect(n1, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t252 = v in self::IntClassExtension|set#property(#t252, self::IntClassExtension|get#property(#t252).{core::num::-}(n1){(core::num*) →* core::int*});
+  self::expect(n0, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t253 = v in let final core::int* #t254 = self::IntClassExtension|get#property(#t253).{core::num::+}(1){(core::num*) →* core::int*} in let final void #t255 = self::IntClassExtension|set#property(#t253, #t254) in #t254;
+  self::expect(n1, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t256 = v in let final core::int* #t257 = self::IntClassExtension|get#property(#t256).{core::num::-}(1){(core::num*) →* core::int*} in let final void #t258 = self::IntClassExtension|set#property(#t256, #t257) in #t257;
+  self::expect(n0, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t259 = v in self::IntClassExtension|set#property(#t259, self::IntClassExtension|get#property(#t259).{core::num::+}(1){(core::num*) →* core::int*});
+  self::expect(n1, self::IntClassExtension|get#property(v));
+  let final self::IntClass* #t260 = v in self::IntClassExtension|set#property(#t260, self::IntClassExtension|get#property(#t260).{core::num::-}(1){(core::num*) →* core::int*});
+  self::expect(n0, self::IntClassExtension|get#property(v));
+}
+static method testExplicitNullAwareProperties(self::Class* v) → dynamic {
+  self::Number* n0 = new self::Number::•(0);
+  self::Number* n1 = new self::Number::•(1);
+  self::Number* n2 = new self::Number::•(2);
+  self::expect(n0, let final self::Class* #t261 = v in #t261 == null ?{self::Number*} null : self::ClassExtension|get#property(#t261), v == null);
+  self::expect(n1, let final self::Class* #t262 = v in #t262 == null ?{self::Number*} null : let final self::Number* #t263 = self::NumberExtension|+(self::ClassExtension|get#property(#t262), n1) in let final void #t264 = self::ClassExtension|set#property(#t262, #t263) in #t263, v == null);
+  self::expect(n2, let final self::Class* #t265 = v in #t265 == null ?{self::Number*} null : let final self::Number* #t266 = self::NumberExtension|+(self::ClassExtension|get#property(#t265), n1) in let final void #t267 = self::ClassExtension|set#property(#t265, #t266) in #t266, v == null);
+  self::expect(n0, let final self::Class* #t268 = v in #t268 == null ?{self::Number*} null : let final self::Number* #t269 = self::NumberExtension|-(self::ClassExtension|get#property(#t268), n2) in let final void #t270 = self::ClassExtension|set#property(#t268, #t269) in #t269, v == null);
+  self::expect(n1, let final self::Class* #t271 = v in #t271 == null ?{self::Number*} null : let final self::Number* #t272 = self::NumberExtension|+(self::ClassExtension|get#property(#t271), n1) in let final void #t273 = self::ClassExtension|set#property(#t271, #t272) in #t272, v == null);
+  self::expect(n0, let final self::Class* #t274 = v in #t274 == null ?{self::Number*} null : let final self::Number* #t275 = self::NumberExtension|-(self::ClassExtension|get#property(#t274), n1) in let final void #t276 = self::ClassExtension|set#property(#t274, #t275) in #t275, v == null);
+  self::expect(n1, let final self::Class* #t277 = v in #t277 == null ?{self::Number*} null : let final self::Number* #t278 = self::NumberExtension|+(self::ClassExtension|get#property(#t277), 1) in let final void #t279 = self::ClassExtension|set#property(#t277, #t278) in #t278, v == null);
+  self::expect(n0, let final self::Class* #t280 = v in #t280 == null ?{self::Number*} null : let final self::Number* #t281 = self::NumberExtension|-(self::ClassExtension|get#property(#t280), 1) in let final void #t282 = self::ClassExtension|set#property(#t280, #t281) in #t281, v == null);
+  self::expect(n0, let final self::Class* #t283 = v in #t283 == null ?{self::Number*} null : let final self::Number* #t284 = self::ClassExtension|get#property(#t283) in let final self::Number* #t285 = let final self::Number* #t286 = self::NumberExtension|+(#t284, 1) in let final void #t287 = self::ClassExtension|set#property(#t283, #t286) in #t286 in #t284, v == null);
+  self::expect(n1, let final self::Class* #t288 = v in #t288 == null ?{self::Number*} null : let final self::Number* #t289 = self::ClassExtension|get#property(#t288) in let final self::Number* #t290 = let final self::Number* #t291 = self::NumberExtension|-(#t289, 1) in let final void #t292 = self::ClassExtension|set#property(#t288, #t291) in #t291 in #t289, v == null);
+  self::expect(n0, let final self::Class* #t293 = v in #t293 == null ?{self::Number*} null : self::ClassExtension|get#property(#t293), v == null);
+  self::expect(n0, let final self::Class* #t294 = v in #t294 == null ?{self::Number*} null : self::ClassExtension|get#property(#t294), v == null);
+  let final self::Class* #t295 = v in #t295 == null ?{self::Number*} null : self::ClassExtension|set#property(#t295, self::NumberExtension|+(self::ClassExtension|get#property(#t295), n1));
+  self::expect(n1, let final self::Class* #t296 = v in #t296 == null ?{self::Number*} null : self::ClassExtension|get#property(#t296), v == null);
+  let final self::Class* #t297 = v in #t297 == null ?{self::Number*} null : self::ClassExtension|set#property(#t297, self::NumberExtension|+(self::ClassExtension|get#property(#t297), n1));
+  self::expect(n2, let final self::Class* #t298 = v in #t298 == null ?{self::Number*} null : self::ClassExtension|get#property(#t298), v == null);
+  let final self::Class* #t299 = v in #t299 == null ?{self::Number*} null : self::ClassExtension|set#property(#t299, self::NumberExtension|-(self::ClassExtension|get#property(#t299), n2));
+  self::expect(n0, let final self::Class* #t300 = v in #t300 == null ?{self::Number*} null : self::ClassExtension|get#property(#t300), v == null);
+  let final self::Class* #t301 = v in #t301 == null ?{self::Number*} null : self::ClassExtension|set#property(#t301, self::NumberExtension|+(self::ClassExtension|get#property(#t301), n1));
+  self::expect(n1, let final self::Class* #t302 = v in #t302 == null ?{self::Number*} null : self::ClassExtension|get#property(#t302), v == null);
+  let final self::Class* #t303 = v in #t303 == null ?{self::Number*} null : self::ClassExtension|set#property(#t303, self::NumberExtension|-(self::ClassExtension|get#property(#t303), n1));
+  self::expect(n0, let final self::Class* #t304 = v in #t304 == null ?{self::Number*} null : self::ClassExtension|get#property(#t304), v == null);
+  let final self::Class* #t305 = v in #t305 == null ?{self::Number*} null : let final self::Number* #t306 = self::NumberExtension|+(self::ClassExtension|get#property(#t305), 1) in let final void #t307 = self::ClassExtension|set#property(#t305, #t306) in #t306;
+  self::expect(n1, let final self::Class* #t308 = v in #t308 == null ?{self::Number*} null : self::ClassExtension|get#property(#t308), v == null);
+  let final self::Class* #t309 = v in #t309 == null ?{self::Number*} null : let final self::Number* #t310 = self::NumberExtension|-(self::ClassExtension|get#property(#t309), 1) in let final void #t311 = self::ClassExtension|set#property(#t309, #t310) in #t310;
+  self::expect(n0, let final self::Class* #t312 = v in #t312 == null ?{self::Number*} null : self::ClassExtension|get#property(#t312), v == null);
+  let final self::Class* #t313 = v in #t313 == null ?{self::Number*} null : self::ClassExtension|set#property(#t313, self::NumberExtension|+(self::ClassExtension|get#property(#t313), 1));
+  self::expect(n1, let final self::Class* #t314 = v in #t314 == null ?{self::Number*} null : self::ClassExtension|get#property(#t314), v == null);
+  let final self::Class* #t315 = v in #t315 == null ?{self::Number*} null : self::ClassExtension|set#property(#t315, self::NumberExtension|-(self::ClassExtension|get#property(#t315), 1));
+  self::expect(n0, let final self::Class* #t316 = v in #t316 == null ?{self::Number*} null : self::ClassExtension|get#property(#t316), v == null);
+}
+static method testExplicitNullAwareIntProperties(self::IntClass* v) → dynamic {
+  core::int* n0 = 0;
+  core::int* n1 = 1;
+  core::int* n2 = 2;
+  self::expect(n0, let final self::IntClass* #t317 = v in #t317 == null ?{core::int*} null : self::IntClassExtension|get#property(#t317), v == null);
+  self::expect(n1, let final self::IntClass* #t318 = v in #t318 == null ?{core::int*} null : let final core::int* #t319 = self::IntClassExtension|get#property(#t318).{core::num::+}(n1){(core::num*) →* core::int*} in let final void #t320 = self::IntClassExtension|set#property(#t318, #t319) in #t319, v == null);
+  self::expect(n2, let final self::IntClass* #t321 = v in #t321 == null ?{core::int*} null : let final core::int* #t322 = self::IntClassExtension|get#property(#t321).{core::num::+}(n1){(core::num*) →* core::int*} in let final void #t323 = self::IntClassExtension|set#property(#t321, #t322) in #t322, v == null);
+  self::expect(n0, let final self::IntClass* #t324 = v in #t324 == null ?{core::int*} null : let final core::int* #t325 = self::IntClassExtension|get#property(#t324).{core::num::-}(n2){(core::num*) →* core::int*} in let final void #t326 = self::IntClassExtension|set#property(#t324, #t325) in #t325, v == null);
+  self::expect(n1, let final self::IntClass* #t327 = v in #t327 == null ?{core::int*} null : let final core::int* #t328 = self::IntClassExtension|get#property(#t327).{core::num::+}(n1){(core::num*) →* core::int*} in let final void #t329 = self::IntClassExtension|set#property(#t327, #t328) in #t328, v == null);
+  self::expect(n0, let final self::IntClass* #t330 = v in #t330 == null ?{core::int*} null : let final core::int* #t331 = self::IntClassExtension|get#property(#t330).{core::num::-}(n1){(core::num*) →* core::int*} in let final void #t332 = self::IntClassExtension|set#property(#t330, #t331) in #t331, v == null);
+  self::expect(n1, let final self::IntClass* #t333 = v in #t333 == null ?{core::int*} null : let final core::int* #t334 = self::IntClassExtension|get#property(#t333).{core::num::+}(1){(core::num*) →* core::int*} in let final void #t335 = self::IntClassExtension|set#property(#t333, #t334) in #t334, v == null);
+  self::expect(n0, let final self::IntClass* #t336 = v in #t336 == null ?{core::int*} null : let final core::int* #t337 = self::IntClassExtension|get#property(#t336).{core::num::-}(1){(core::num*) →* core::int*} in let final void #t338 = self::IntClassExtension|set#property(#t336, #t337) in #t337, v == null);
+  self::expect(n0, let final self::IntClass* #t339 = v in #t339 == null ?{core::int*} null : let final core::int* #t340 = self::IntClassExtension|get#property(#t339) in let final core::int* #t341 = let final core::int* #t342 = #t340.{core::num::+}(1){(core::num*) →* core::int*} in let final void #t343 = self::IntClassExtension|set#property(#t339, #t342) in #t342 in #t340, v == null);
+  self::expect(n1, let final self::IntClass* #t344 = v in #t344 == null ?{core::int*} null : let final core::int* #t345 = self::IntClassExtension|get#property(#t344) in let final core::int* #t346 = let final core::int* #t347 = #t345.{core::num::-}(1){(core::num*) →* core::int*} in let final void #t348 = self::IntClassExtension|set#property(#t344, #t347) in #t347 in #t345, v == null);
+  self::expect(n0, let final self::IntClass* #t349 = v in #t349 == null ?{core::int*} null : self::IntClassExtension|get#property(#t349), v == null);
+  self::expect(n0, let final self::IntClass* #t350 = v in #t350 == null ?{core::int*} null : self::IntClassExtension|get#property(#t350), v == null);
+  let final self::IntClass* #t351 = v in #t351 == null ?{core::int*} null : self::IntClassExtension|set#property(#t351, self::IntClassExtension|get#property(#t351).{core::num::+}(n1){(core::num*) →* core::int*});
+  self::expect(n1, let final self::IntClass* #t352 = v in #t352 == null ?{core::int*} null : self::IntClassExtension|get#property(#t352), v == null);
+  let final self::IntClass* #t353 = v in #t353 == null ?{core::int*} null : self::IntClassExtension|set#property(#t353, self::IntClassExtension|get#property(#t353).{core::num::+}(n1){(core::num*) →* core::int*});
+  self::expect(n2, let final self::IntClass* #t354 = v in #t354 == null ?{core::int*} null : self::IntClassExtension|get#property(#t354), v == null);
+  let final self::IntClass* #t355 = v in #t355 == null ?{core::int*} null : self::IntClassExtension|set#property(#t355, self::IntClassExtension|get#property(#t355).{core::num::-}(n2){(core::num*) →* core::int*});
+  self::expect(n0, let final self::IntClass* #t356 = v in #t356 == null ?{core::int*} null : self::IntClassExtension|get#property(#t356), v == null);
+  let final self::IntClass* #t357 = v in #t357 == null ?{core::int*} null : self::IntClassExtension|set#property(#t357, self::IntClassExtension|get#property(#t357).{core::num::+}(n1){(core::num*) →* core::int*});
+  self::expect(n1, let final self::IntClass* #t358 = v in #t358 == null ?{core::int*} null : self::IntClassExtension|get#property(#t358), v == null);
+  let final self::IntClass* #t359 = v in #t359 == null ?{core::int*} null : self::IntClassExtension|set#property(#t359, self::IntClassExtension|get#property(#t359).{core::num::-}(n1){(core::num*) →* core::int*});
+  self::expect(n0, let final self::IntClass* #t360 = v in #t360 == null ?{core::int*} null : self::IntClassExtension|get#property(#t360), v == null);
+  let final self::IntClass* #t361 = v in #t361 == null ?{core::int*} null : let final core::int* #t362 = self::IntClassExtension|get#property(#t361).{core::num::+}(1){(core::num*) →* core::int*} in let final void #t363 = self::IntClassExtension|set#property(#t361, #t362) in #t362;
+  self::expect(n1, let final self::IntClass* #t364 = v in #t364 == null ?{core::int*} null : self::IntClassExtension|get#property(#t364), v == null);
+  let final self::IntClass* #t365 = v in #t365 == null ?{core::int*} null : let final core::int* #t366 = self::IntClassExtension|get#property(#t365).{core::num::-}(1){(core::num*) →* core::int*} in let final void #t367 = self::IntClassExtension|set#property(#t365, #t366) in #t366;
+  self::expect(n0, let final self::IntClass* #t368 = v in #t368 == null ?{core::int*} null : self::IntClassExtension|get#property(#t368), v == null);
+  let final self::IntClass* #t369 = v in #t369 == null ?{core::int*} null : self::IntClassExtension|set#property(#t369, self::IntClassExtension|get#property(#t369).{core::num::+}(1){(core::num*) →* core::int*});
+  self::expect(n1, let final self::IntClass* #t370 = v in #t370 == null ?{core::int*} null : self::IntClassExtension|get#property(#t370), v == null);
+  let final self::IntClass* #t371 = v in #t371 == null ?{core::int*} null : self::IntClassExtension|set#property(#t371, self::IntClassExtension|get#property(#t371).{core::num::-}(1){(core::num*) →* core::int*});
+  self::expect(n0, let final self::IntClass* #t372 = v in #t372 == null ?{core::int*} null : self::IntClassExtension|get#property(#t372), v == null);
+}
+static method expect(dynamic expected, dynamic actual, [dynamic expectNull = #C1]) → dynamic {
+  if(expectNull as{TypeError,ForDynamic} core::bool*) {
+    expected = null;
+  }
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
+
+constants  {
+  #C1 = false
+}
diff --git a/pkg/front_end/testcases/extensions/conflict_with_object.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/conflict_with_object.dart.weak.modular.expect
new file mode 100644
index 0000000..101c651
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/conflict_with_object.dart.weak.modular.expect
@@ -0,0 +1,91 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/conflict_with_object.dart:6:11: Error: This extension member conflicts with Object member 'noSuchMethod'.
+//   int get noSuchMethod => 42;
+//           ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/conflict_with_object.dart:8:7: Error: This extension member conflicts with Object member 'runtimeType'.
+//   int runtimeType() {}
+//       ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/conflict_with_object.dart:9:12: Error: This extension member conflicts with Object member '=='.
+//   operator ==(other) => false;
+//            ^^
+//
+// pkg/front_end/testcases/extensions/conflict_with_object.dart:10:17: Error: This extension member conflicts with Object member 'toString'.
+//   static String toString() => 'Foo';
+//                 ^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/conflict_with_object.dart:7:12: Error: This extension member conflicts with Object member 'hashCode'.
+//   void set hashCode(int value) {}
+//            ^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/conflict_with_object.dart:27:14: Error: A value of type 'dynamic Function(Invocation)' can't be assigned to a variable of type 'int'.
+//  - 'Invocation' is from 'dart:core'.
+//   value = "".noSuchMethod;
+//              ^
+//
+// pkg/front_end/testcases/extensions/conflict_with_object.dart:28:6: Error: The setter 'hashCode' isn't defined for the class 'String'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'hashCode'.
+//   "".hashCode = 42;
+//      ^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/conflict_with_object.dart:29:14: Error: A value of type 'Type' can't be assigned to a variable of type 'int'.
+//  - 'Type' is from 'dart:core'.
+//   value = "".runtimeType;
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+
+extension Extension on core::String* {
+  get noSuchMethod = self::Extension|get#noSuchMethod;
+  method runtimeType = self::Extension|runtimeType;
+  tearoff runtimeType = self::Extension|get#runtimeType;
+  operator == = self::Extension|==;
+  static method toString = self::Extension|toString;
+  set hashCode = self::Extension|set#hashCode;
+}
+static method Extension|get#noSuchMethod(lowered final core::String* #this) → core::int*
+  return 42;
+static method Extension|set#hashCode(lowered final core::String* #this, core::int* value) → void {}
+static method Extension|runtimeType(lowered final core::String* #this) → core::int* {}
+static method Extension|get#runtimeType(lowered final core::String* #this) → () →* core::int*
+  return () → core::int* => self::Extension|runtimeType(#this);
+static method Extension|==(lowered final core::String* #this, dynamic other) → dynamic
+  return false;
+static method Extension|toString() → core::String*
+  return "Foo";
+static method main() → dynamic {
+  core::int* value;
+  self::expect(true, "".{core::Object::noSuchMethod}{(core::Invocation*) →* dynamic} is core::Function*);
+  value = self::Extension|get#noSuchMethod("");
+  self::Extension|set#hashCode("", 42);
+  self::expect(true, "".{core::Object::runtimeType}{core::Type*} is core::Type*);
+  self::expect(true, self::Extension|get#runtimeType("") is core::Function*);
+  value = self::Extension|runtimeType("");
+  self::expect(true, "" =={core::String::==}{(core::Object*) →* core::bool*} "");
+  self::expect("Foo", self::Extension|toString());
+}
+static method errors() → dynamic {
+  core::int* value;
+  value = invalid-expression "pkg/front_end/testcases/extensions/conflict_with_object.dart:27:14: Error: A value of type 'dynamic Function(Invocation)' can't be assigned to a variable of type 'int'.
+ - 'Invocation' is from 'dart:core'.
+  value = \"\".noSuchMethod;
+             ^" in "".{core::Object::noSuchMethod}{(core::Invocation*) →* dynamic} as{TypeError} core::int*;
+  invalid-expression "pkg/front_end/testcases/extensions/conflict_with_object.dart:28:6: Error: The setter 'hashCode' isn't defined for the class 'String'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'hashCode'.
+  \"\".hashCode = 42;
+     ^^^^^^^^" in ""{<unresolved>}.hashCode = 42;
+  value = invalid-expression "pkg/front_end/testcases/extensions/conflict_with_object.dart:29:14: Error: A value of type 'Type' can't be assigned to a variable of type 'int'.
+ - 'Type' is from 'dart:core'.
+  value = \"\".runtimeType;
+             ^" in "".{core::Object::runtimeType}{core::Type*} as{TypeError} core::int*;
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/conflicts.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/conflicts.dart.weak.modular.expect
new file mode 100644
index 0000000..3373345
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/conflicts.dart.weak.modular.expect
@@ -0,0 +1,90 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/conflicts.dart:14:11: Error: 'DuplicateExtensionName' is already declared in this scope.
+// extension DuplicateExtensionName on Class2 {
+//           ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/conflicts.dart:9:11: Context: Previous declaration of 'DuplicateExtensionName'.
+// extension DuplicateExtensionName on Class1 {
+//           ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/conflicts.dart:21:3: Error: 'duplicateMethodName1' is already declared in this scope.
+//   duplicateMethodName1() => 2;
+//   ^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/conflicts.dart:20:3: Context: Previous declaration of 'duplicateMethodName1'.
+//   duplicateMethodName1() => 1;
+//   ^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/conflicts.dart:31:6: Error: The method 'uniqueMethod2' isn't defined for the class 'Class2'.
+//  - 'Class2' is from 'pkg/front_end/testcases/extensions/conflicts.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'uniqueMethod2'.
+//   c2.uniqueMethod2();
+//      ^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension DuplicateExtensionName on self::Class1* {
+  method uniqueMethod1 = self::DuplicateExtensionName|uniqueMethod1;
+  tearoff uniqueMethod1 = self::DuplicateExtensionName|get#uniqueMethod1;
+  method duplicateMethodName2 = self::DuplicateExtensionName|duplicateMethodName2;
+  tearoff duplicateMethodName2 = self::DuplicateExtensionName|get#duplicateMethodName2;
+}
+extension UniqueExtensionName on self::Class1* {
+  method duplicateMethodName1 = self::UniqueExtensionName|duplicateMethodName1;
+  tearoff duplicateMethodName1 = self::UniqueExtensionName|get#duplicateMethodName1;
+}
+static method DuplicateExtensionName|uniqueMethod1(lowered final self::Class1* #this) → dynamic {}
+static method DuplicateExtensionName|get#uniqueMethod1(lowered final self::Class1* #this) → () →* dynamic
+  return () → dynamic => self::DuplicateExtensionName|uniqueMethod1(#this);
+static method DuplicateExtensionName|duplicateMethodName2(lowered final self::Class1* #this) → dynamic
+  return 1;
+static method DuplicateExtensionName|get#duplicateMethodName2(lowered final self::Class1* #this) → () →* dynamic
+  return () → dynamic => self::DuplicateExtensionName|duplicateMethodName2(#this);
+static method UniqueExtensionName|duplicateMethodName1(lowered final self::Class1* #this) → dynamic
+  return 1;
+static method UniqueExtensionName|get#duplicateMethodName1(lowered final self::Class1* #this) → () →* dynamic
+  return () → dynamic => self::UniqueExtensionName|duplicateMethodName1(#this);
+static method main() → dynamic {
+  self::Class1* c1 = new self::Class1::•();
+  self::DuplicateExtensionName|uniqueMethod1(c1);
+}
+static method errors() → dynamic {
+  self::Class2* c2 = new self::Class2::•();
+  invalid-expression "pkg/front_end/testcases/extensions/conflicts.dart:31:6: Error: The method 'uniqueMethod2' isn't defined for the class 'Class2'.
+ - 'Class2' is from 'pkg/front_end/testcases/extensions/conflicts.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'uniqueMethod2'.
+  c2.uniqueMethod2();
+     ^^^^^^^^^^^^^" in c2{<unresolved>}.uniqueMethod2();
+}
diff --git a/pkg/front_end/testcases/extensions/default_values.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/default_values.dart.weak.modular.expect
new file mode 100644
index 0000000..99dd7ec
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/default_values.dart.weak.modular.expect
@@ -0,0 +1,75 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+  method method0 = self::Extension|method0;
+  tearoff method0 = self::Extension|get#method0;
+  method method1 = self::Extension|method1;
+  tearoff method1 = self::Extension|get#method1;
+  method method2 = self::Extension|method2;
+  tearoff method2 = self::Extension|get#method2;
+  method method3 = self::Extension|method3;
+  tearoff method3 = self::Extension|get#method3;
+  static method staticMethod = self::Extension|staticMethod;
+}
+static method Extension|method0(lowered final self::Class* #this, [dynamic a = #C1]) → dynamic
+  return a;
+static method Extension|get#method0(lowered final self::Class* #this) → ([dynamic]) →* dynamic
+  return ([dynamic a = #C1]) → dynamic => self::Extension|method0(#this, a);
+static method Extension|method1(lowered final self::Class* #this, [dynamic a = #C2]) → dynamic
+  return a;
+static method Extension|get#method1(lowered final self::Class* #this) → ([dynamic]) →* dynamic
+  return ([dynamic a = #C2]) → dynamic => self::Extension|method1(#this, a);
+static method Extension|method2(lowered final self::Class* #this, {dynamic b = #C3}) → dynamic
+  return b;
+static method Extension|get#method2(lowered final self::Class* #this) → ({b: dynamic}) →* dynamic
+  return ({dynamic b = #C3}) → dynamic => self::Extension|method2(#this, b: b);
+static method Extension|method3(lowered final self::Class* #this, {dynamic c = #C4}) → dynamic
+  return c{dynamic}.call();
+static method Extension|get#method3(lowered final self::Class* #this) → ({c: dynamic}) →* dynamic
+  return ({dynamic c = #C4}) → dynamic => self::Extension|method3(#this, c: c);
+static method Extension|staticMethod() → dynamic
+  return 123;
+static method main() → dynamic {
+  self::Class* c = new self::Class::•();
+  ([dynamic]) →* dynamic tearOff0 = self::Extension|get#method0(c);
+  self::expect(0, tearOff0(0){([dynamic]) →* dynamic});
+  self::expect(null, tearOff0(){([dynamic]) →* dynamic});
+  ([dynamic]) →* dynamic tearOff1 = self::Extension|get#method1(c);
+  self::expect(0, tearOff1(0){([dynamic]) →* dynamic});
+  self::expect(42, tearOff1(){([dynamic]) →* dynamic});
+  ({b: dynamic}) →* dynamic tearOff2 = self::Extension|get#method2(c);
+  self::expect(0, tearOff2(b: 0){({b: dynamic}) →* dynamic});
+  self::expect(87, tearOff2(){({b: dynamic}) →* dynamic});
+  ({c: dynamic}) →* dynamic tearOff3 = self::Extension|get#method3(c);
+  self::expect(0, tearOff3(c: () → core::int* => 0){({c: dynamic}) →* dynamic});
+  self::expect(123, tearOff3(){({c: dynamic}) →* dynamic});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
+
+constants  {
+  #C1 = null
+  #C2 = 42
+  #C3 = 87
+  #C4 = static-tearoff self::Extension|staticMethod
+}
diff --git a/pkg/front_end/testcases/extensions/deferred_explicit_access.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/deferred_explicit_access.dart.weak.modular.expect
new file mode 100644
index 0000000..a3e0d9a
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/deferred_explicit_access.dart.weak.modular.expect
@@ -0,0 +1,70 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/deferred_explicit_access.dart:5:1: Error: Extension 'Extension' cannot be imported through a deferred import.
+// Try adding the `hide Extension` to the import.
+// import 'deferred_explicit_access_lib.dart' deferred as prefix;
+// ^
+//
+import self as self;
+import "deferred_explicit_access_lib.dart" as def;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///deferred_explicit_access_lib.dart" deferred as prefix;
+
+static method main() → dynamic async {
+  await LoadLibrary(prefix);
+  self::expect(0, let final dynamic #t1 = CheckLibraryIsLoaded(prefix) in def::Extension|staticField);
+  self::expect(0, let final dynamic #t2 = CheckLibraryIsLoaded(prefix) in def::Extension|get#property(0));
+  self::expect(42, let final dynamic #t3 = CheckLibraryIsLoaded(prefix) in let final core::int* #t4 = 0 in let final core::int* #t5 = 42 in let final void #t6 = def::Extension|set#property(#t4, #t5) in #t5);
+  self::expect(84, let final dynamic #t7 = CheckLibraryIsLoaded(prefix) in def::Extension|get#property(42));
+  self::expect(85, let final dynamic #t8 = CheckLibraryIsLoaded(prefix) in def::Extension|method(43));
+  self::expect(42, let final dynamic #t9 = CheckLibraryIsLoaded(prefix) in def::Extension|staticProperty);
+  self::expect(87, let final dynamic #t10 = CheckLibraryIsLoaded(prefix) in def::Extension|staticProperty = 87);
+  self::expect(87, let final dynamic #t11 = CheckLibraryIsLoaded(prefix) in def::Extension|staticMethod());
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+library;
+import self as def;
+import "dart:core" as core;
+
+extension Extension on core::int* {
+  static field staticField = def::Extension|staticField;
+  static get staticProperty = get def::Extension|staticProperty;
+  static method staticMethod = def::Extension|staticMethod;
+  get property = def::Extension|get#property;
+  method method = def::Extension|method;
+  tearoff method = def::Extension|get#method;
+  static set staticProperty = set def::Extension|staticProperty;
+  set property = def::Extension|set#property;
+}
+static field core::int* Extension|staticField = 0;
+static field core::int* topLevelField = def::Extension|staticField;
+static get Extension|staticProperty() → core::int*
+  return def::Extension|staticField;
+static set Extension|staticProperty(core::int* value) → void {
+  def::Extension|staticField = value;
+}
+static method Extension|staticMethod() → core::int*
+  return def::Extension|staticField;
+static method Extension|get#property(lowered final core::int* #this) → core::int*
+  return #this.{core::num::+}(def::Extension|staticField){(core::num*) →* core::int*};
+static method Extension|set#property(lowered final core::int* #this, core::int* value) → void {
+  def::Extension|staticField = value;
+}
+static method Extension|method(lowered final core::int* #this) → core::int*
+  return #this.{core::num::+}(def::Extension|staticField){(core::num*) →* core::int*};
+static method Extension|get#method(lowered final core::int* #this) → () →* core::int*
+  return () → core::int* => def::Extension|method(#this);
+static get topLevelProperty() → core::int*
+  return def::Extension|staticField;
+static set topLevelProperty(core::int* value) → void {
+  def::Extension|staticField = value;
+}
+static method topLevelMethod() → dynamic
+  return def::Extension|staticField;
diff --git a/pkg/front_end/testcases/extensions/deferred_import_hidden.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/deferred_import_hidden.dart.weak.modular.expect
new file mode 100644
index 0000000..ddd41d6
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/deferred_import_hidden.dart.weak.modular.expect
@@ -0,0 +1,61 @@
+library;
+import self as self;
+import "deferred_explicit_access_lib.dart" as def;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///deferred_explicit_access_lib.dart" deferred as prefix hide Extension;
+
+static method main() → dynamic async {
+  await LoadLibrary(prefix);
+  self::expect(0, let final dynamic #t1 = CheckLibraryIsLoaded(prefix) in def::topLevelField);
+  self::expect(42, let final dynamic #t2 = CheckLibraryIsLoaded(prefix) in def::topLevelField = 42);
+  self::expect(42, let final dynamic #t3 = CheckLibraryIsLoaded(prefix) in def::topLevelField);
+  self::expect(0, let final dynamic #t4 = CheckLibraryIsLoaded(prefix) in def::topLevelProperty);
+  self::expect(87, let final dynamic #t5 = CheckLibraryIsLoaded(prefix) in def::topLevelProperty = 87);
+  self::expect(87, let final dynamic #t6 = CheckLibraryIsLoaded(prefix) in def::topLevelProperty);
+  self::expect(87, let final dynamic #t7 = CheckLibraryIsLoaded(prefix) in def::topLevelMethod());
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+library;
+import self as def;
+import "dart:core" as core;
+
+extension Extension on core::int* {
+  static field staticField = def::Extension|staticField;
+  static get staticProperty = get def::Extension|staticProperty;
+  static method staticMethod = def::Extension|staticMethod;
+  get property = def::Extension|get#property;
+  method method = def::Extension|method;
+  tearoff method = def::Extension|get#method;
+  static set staticProperty = set def::Extension|staticProperty;
+  set property = def::Extension|set#property;
+}
+static field core::int* Extension|staticField = 0;
+static field core::int* topLevelField = def::Extension|staticField;
+static get Extension|staticProperty() → core::int*
+  return def::Extension|staticField;
+static set Extension|staticProperty(core::int* value) → void {
+  def::Extension|staticField = value;
+}
+static method Extension|staticMethod() → core::int*
+  return def::Extension|staticField;
+static method Extension|get#property(lowered final core::int* #this) → core::int*
+  return #this.{core::num::+}(def::Extension|staticField){(core::num*) →* core::int*};
+static method Extension|set#property(lowered final core::int* #this, core::int* value) → void {
+  def::Extension|staticField = value;
+}
+static method Extension|method(lowered final core::int* #this) → core::int*
+  return #this.{core::num::+}(def::Extension|staticField){(core::num*) →* core::int*};
+static method Extension|get#method(lowered final core::int* #this) → () →* core::int*
+  return () → core::int* => def::Extension|method(#this);
+static get topLevelProperty() → core::int*
+  return def::Extension|staticField;
+static set topLevelProperty(core::int* value) → void {
+  def::Extension|staticField = value;
+}
+static method topLevelMethod() → dynamic
+  return def::Extension|staticField;
diff --git a/pkg/front_end/testcases/extensions/direct_instance_access.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/direct_instance_access.dart.weak.modular.expect
new file mode 100644
index 0000000..d892e0f
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/direct_instance_access.dart.weak.modular.expect
@@ -0,0 +1,297 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field dynamic field = null;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class GenericClass<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::GenericClass::T* field = null;
+  synthetic constructor •() → self::GenericClass<self::GenericClass::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+  method readGetter = self::Extension|readGetter;
+  tearoff readGetter = self::Extension|get#readGetter;
+  method writeSetterRequired = self::Extension|writeSetterRequired;
+  tearoff writeSetterRequired = self::Extension|get#writeSetterRequired;
+  method writeSetterOptional = self::Extension|writeSetterOptional;
+  tearoff writeSetterOptional = self::Extension|get#writeSetterOptional;
+  method writeSetterNamed = self::Extension|writeSetterNamed;
+  tearoff writeSetterNamed = self::Extension|get#writeSetterNamed;
+  get tearOffGetterNoArgs = self::Extension|get#tearOffGetterNoArgs;
+  get tearOffGetterRequired = self::Extension|get#tearOffGetterRequired;
+  get tearOffGetterOptional = self::Extension|get#tearOffGetterOptional;
+  get tearOffGetterNamed = self::Extension|get#tearOffGetterNamed;
+  get property = self::Extension|get#property;
+  method invocations = self::Extension|invocations;
+  tearoff invocations = self::Extension|get#invocations;
+  method tearOffs = self::Extension|tearOffs;
+  tearoff tearOffs = self::Extension|get#tearOffs;
+  method getterCalls = self::Extension|getterCalls;
+  tearoff getterCalls = self::Extension|get#getterCalls;
+  set property = self::Extension|set#property;
+}
+extension GenericExtension<T extends core::Object* = dynamic> on self::GenericClass<T*>* {
+  method readGetter = self::GenericExtension|readGetter;
+  tearoff readGetter = self::GenericExtension|get#readGetter;
+  method writeSetterRequired = self::GenericExtension|writeSetterRequired;
+  tearoff writeSetterRequired = self::GenericExtension|get#writeSetterRequired;
+  method writeSetterOptional = self::GenericExtension|writeSetterOptional;
+  tearoff writeSetterOptional = self::GenericExtension|get#writeSetterOptional;
+  method writeSetterNamed = self::GenericExtension|writeSetterNamed;
+  tearoff writeSetterNamed = self::GenericExtension|get#writeSetterNamed;
+  method genericWriteSetterRequired = self::GenericExtension|genericWriteSetterRequired;
+  tearoff genericWriteSetterRequired = self::GenericExtension|get#genericWriteSetterRequired;
+  method genericWriteSetterOptional = self::GenericExtension|genericWriteSetterOptional;
+  tearoff genericWriteSetterOptional = self::GenericExtension|get#genericWriteSetterOptional;
+  method genericWriteSetterNamed = self::GenericExtension|genericWriteSetterNamed;
+  tearoff genericWriteSetterNamed = self::GenericExtension|get#genericWriteSetterNamed;
+  get property = self::GenericExtension|get#property;
+  get tearOffGetterNoArgs = self::GenericExtension|get#tearOffGetterNoArgs;
+  get tearOffGetterRequired = self::GenericExtension|get#tearOffGetterRequired;
+  get tearOffGetterOptional = self::GenericExtension|get#tearOffGetterOptional;
+  get tearOffGetterNamed = self::GenericExtension|get#tearOffGetterNamed;
+  get tearOffGetterGenericRequired = self::GenericExtension|get#tearOffGetterGenericRequired;
+  get tearOffGetterGenericOptional = self::GenericExtension|get#tearOffGetterGenericOptional;
+  get tearOffGetterGenericNamed = self::GenericExtension|get#tearOffGetterGenericNamed;
+  method invocations = self::GenericExtension|invocations;
+  tearoff invocations = self::GenericExtension|get#invocations;
+  method tearOffs = self::GenericExtension|tearOffs;
+  tearoff tearOffs = self::GenericExtension|get#tearOffs;
+  method getterCalls = self::GenericExtension|getterCalls;
+  tearoff getterCalls = self::GenericExtension|get#getterCalls;
+  set property = self::GenericExtension|set#property;
+}
+static method Extension|get#readGetter(lowered final self::Class* #this) → () →* dynamic
+  return () → dynamic => self::Extension|readGetter(#this);
+static method Extension|readGetter(lowered final self::Class* #this) → dynamic {
+  return self::Extension|get#property(#this);
+}
+static method Extension|writeSetterRequired(lowered final self::Class* #this, dynamic value) → dynamic {
+  self::Extension|set#property(#this, value);
+}
+static method Extension|get#writeSetterRequired(lowered final self::Class* #this) → (dynamic) →* dynamic
+  return (dynamic value) → dynamic => self::Extension|writeSetterRequired(#this, value);
+static method Extension|writeSetterOptional(lowered final self::Class* #this, [dynamic value = #C1]) → dynamic {
+  self::Extension|set#property(#this, value);
+}
+static method Extension|get#writeSetterOptional(lowered final self::Class* #this) → ([dynamic]) →* dynamic
+  return ([dynamic value = #C1]) → dynamic => self::Extension|writeSetterOptional(#this, value);
+static method Extension|writeSetterNamed(lowered final self::Class* #this, {dynamic value = #C1}) → dynamic {
+  self::Extension|set#property(#this, value);
+}
+static method Extension|get#writeSetterNamed(lowered final self::Class* #this) → ({value: dynamic}) →* dynamic
+  return ({dynamic value = #C1}) → dynamic => self::Extension|writeSetterNamed(#this, value: value);
+static method Extension|get#tearOffGetterNoArgs(lowered final self::Class* #this) → dynamic
+  return self::Extension|get#readGetter(#this);
+static method Extension|get#tearOffGetterRequired(lowered final self::Class* #this) → dynamic
+  return self::Extension|get#writeSetterRequired(#this);
+static method Extension|get#tearOffGetterOptional(lowered final self::Class* #this) → dynamic
+  return self::Extension|get#writeSetterOptional(#this);
+static method Extension|get#tearOffGetterNamed(lowered final self::Class* #this) → dynamic
+  return self::Extension|get#writeSetterNamed(#this);
+static method Extension|get#property(lowered final self::Class* #this) → dynamic
+  return #this.{self::Class::field}{dynamic};
+static method Extension|set#property(lowered final self::Class* #this, dynamic value) → void {
+  #this.{self::Class::field} = value;
+}
+static method Extension|invocations(lowered final self::Class* #this, dynamic value) → dynamic {
+  self::Extension|readGetter(#this);
+  self::Extension|writeSetterRequired(#this, value);
+  self::Extension|writeSetterOptional(#this);
+  self::Extension|writeSetterOptional(#this, value);
+  self::Extension|writeSetterNamed(#this);
+  self::Extension|writeSetterNamed(#this, value: value);
+}
+static method Extension|get#invocations(lowered final self::Class* #this) → (dynamic) →* dynamic
+  return (dynamic value) → dynamic => self::Extension|invocations(#this, value);
+static method Extension|get#tearOffs(lowered final self::Class* #this) → (dynamic) →* dynamic
+  return (dynamic value) → dynamic => self::Extension|tearOffs(#this, value);
+static method Extension|tearOffs(lowered final self::Class* #this, dynamic value) → dynamic {
+  () →* dynamic tearOffNoArgs = self::Extension|get#readGetter(#this);
+  tearOffNoArgs(){() →* dynamic};
+  (dynamic) →* dynamic tearOffRequired = self::Extension|get#writeSetterRequired(#this);
+  tearOffRequired(value){(dynamic) →* dynamic};
+  ([dynamic]) →* dynamic tearOffOptional = self::Extension|get#writeSetterOptional(#this);
+  tearOffOptional(){([dynamic]) →* dynamic};
+  tearOffOptional(value){([dynamic]) →* dynamic};
+  ({value: dynamic}) →* dynamic tearOffNamed = self::Extension|get#writeSetterNamed(#this);
+  tearOffNamed(){({value: dynamic}) →* dynamic};
+  tearOffNamed(value: value){({value: dynamic}) →* dynamic};
+}
+static method Extension|getterCalls(lowered final self::Class* #this, dynamic value) → dynamic {
+  self::Extension|get#tearOffGetterNoArgs(#this){dynamic}.call();
+  self::Extension|get#tearOffGetterRequired(#this){dynamic}.call(value);
+  self::Extension|get#tearOffGetterOptional(#this){dynamic}.call();
+  self::Extension|get#tearOffGetterOptional(#this){dynamic}.call(value);
+  self::Extension|get#tearOffGetterNamed(#this){dynamic}.call();
+  self::Extension|get#tearOffGetterNamed(#this){dynamic}.call(value: value);
+}
+static method Extension|get#getterCalls(lowered final self::Class* #this) → (dynamic) →* dynamic
+  return (dynamic value) → dynamic => self::Extension|getterCalls(#this, value);
+static method GenericExtension|readGetter<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|readGetter::T*>* #this) → self::GenericExtension|readGetter::T* {
+  return self::GenericExtension|get#property<self::GenericExtension|readGetter::T*>(#this);
+}
+static method GenericExtension|get#readGetter<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#readGetter::T*>* #this) → () →* self::GenericExtension|get#readGetter::T*
+  return () → self::GenericExtension|get#readGetter::T* => self::GenericExtension|readGetter<self::GenericExtension|get#readGetter::T*>(#this);
+static method GenericExtension|writeSetterRequired<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|writeSetterRequired::T*>* #this, self::GenericExtension|writeSetterRequired::T* value) → dynamic {
+  self::GenericExtension|set#property<self::GenericExtension|writeSetterRequired::T*>(#this, value);
+}
+static method GenericExtension|get#writeSetterRequired<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#writeSetterRequired::T*>* #this) → (self::GenericExtension|get#writeSetterRequired::T*) →* dynamic
+  return (self::GenericExtension|get#writeSetterRequired::T* value) → dynamic => self::GenericExtension|writeSetterRequired<self::GenericExtension|get#writeSetterRequired::T*>(#this, value);
+static method GenericExtension|writeSetterOptional<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|writeSetterOptional::T*>* #this, [self::GenericExtension|writeSetterOptional::T* value = #C1]) → dynamic {
+  self::GenericExtension|set#property<self::GenericExtension|writeSetterOptional::T*>(#this, value);
+}
+static method GenericExtension|get#writeSetterOptional<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#writeSetterOptional::T*>* #this) → ([self::GenericExtension|get#writeSetterOptional::T*]) →* dynamic
+  return ([self::GenericExtension|get#writeSetterOptional::T* value = #C1]) → dynamic => self::GenericExtension|writeSetterOptional<self::GenericExtension|get#writeSetterOptional::T*>(#this, value);
+static method GenericExtension|writeSetterNamed<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|writeSetterNamed::T*>* #this, {self::GenericExtension|writeSetterNamed::T* value = #C1}) → dynamic {
+  self::GenericExtension|set#property<self::GenericExtension|writeSetterNamed::T*>(#this, value);
+}
+static method GenericExtension|get#writeSetterNamed<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#writeSetterNamed::T*>* #this) → ({value: self::GenericExtension|get#writeSetterNamed::T*}) →* dynamic
+  return ({self::GenericExtension|get#writeSetterNamed::T* value = #C1}) → dynamic => self::GenericExtension|writeSetterNamed<self::GenericExtension|get#writeSetterNamed::T*>(#this, value: value);
+static method GenericExtension|genericWriteSetterRequired<T extends core::Object* = dynamic, S extends self::GenericExtension|genericWriteSetterRequired::T* = dynamic>(lowered final self::GenericClass<self::GenericExtension|genericWriteSetterRequired::T*>* #this, self::GenericExtension|genericWriteSetterRequired::S* value) → dynamic {
+  self::GenericExtension|set#property<self::GenericExtension|genericWriteSetterRequired::T*>(#this, value);
+}
+static method GenericExtension|get#genericWriteSetterRequired<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#genericWriteSetterRequired::T*>* #this) → <S extends self::GenericExtension|get#genericWriteSetterRequired::T* = dynamic>(S*) →* dynamic
+  return <S extends self::GenericExtension|get#genericWriteSetterRequired::T* = dynamic>(S* value) → dynamic => self::GenericExtension|genericWriteSetterRequired<self::GenericExtension|get#genericWriteSetterRequired::T*, S*>(#this, value);
+static method GenericExtension|genericWriteSetterOptional<T extends core::Object* = dynamic, S extends self::GenericExtension|genericWriteSetterOptional::T* = dynamic>(lowered final self::GenericClass<self::GenericExtension|genericWriteSetterOptional::T*>* #this, [self::GenericExtension|genericWriteSetterOptional::S* value = #C1]) → dynamic {
+  self::GenericExtension|set#property<self::GenericExtension|genericWriteSetterOptional::T*>(#this, value);
+}
+static method GenericExtension|get#genericWriteSetterOptional<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#genericWriteSetterOptional::T*>* #this) → <S extends self::GenericExtension|get#genericWriteSetterOptional::T* = dynamic>([S*]) →* dynamic
+  return <S extends self::GenericExtension|get#genericWriteSetterOptional::T* = dynamic>([S* value = #C1]) → dynamic => self::GenericExtension|genericWriteSetterOptional<self::GenericExtension|get#genericWriteSetterOptional::T*, S*>(#this, value);
+static method GenericExtension|get#genericWriteSetterNamed<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#genericWriteSetterNamed::T*>* #this) → <S extends self::GenericExtension|get#genericWriteSetterNamed::T* = dynamic>({value: S*}) →* dynamic
+  return <S extends self::GenericExtension|get#genericWriteSetterNamed::T* = dynamic>({S* value = #C1}) → dynamic => self::GenericExtension|genericWriteSetterNamed<self::GenericExtension|get#genericWriteSetterNamed::T*, S*>(#this, value: value);
+static method GenericExtension|genericWriteSetterNamed<T extends core::Object* = dynamic, S extends self::GenericExtension|genericWriteSetterNamed::T* = dynamic>(lowered final self::GenericClass<self::GenericExtension|genericWriteSetterNamed::T*>* #this, {self::GenericExtension|genericWriteSetterNamed::S* value = #C1}) → dynamic {
+  self::GenericExtension|set#property<self::GenericExtension|genericWriteSetterNamed::T*>(#this, value);
+}
+static method GenericExtension|get#property<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#property::T*>* #this) → self::GenericExtension|get#property::T*
+  return #this.{self::GenericClass::field}{self::GenericExtension|get#property::T*};
+static method GenericExtension|set#property<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|set#property::T*>* #this, self::GenericExtension|set#property::T* value) → void {
+  #this.{self::GenericClass::field} = value;
+}
+static method GenericExtension|get#tearOffGetterNoArgs<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#tearOffGetterNoArgs::T*>* #this) → dynamic
+  return self::GenericExtension|get#readGetter<self::GenericExtension|get#tearOffGetterNoArgs::T*>(#this);
+static method GenericExtension|get#tearOffGetterRequired<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#tearOffGetterRequired::T*>* #this) → dynamic
+  return self::GenericExtension|get#writeSetterRequired<self::GenericExtension|get#tearOffGetterRequired::T*>(#this);
+static method GenericExtension|get#tearOffGetterOptional<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#tearOffGetterOptional::T*>* #this) → dynamic
+  return self::GenericExtension|get#writeSetterOptional<self::GenericExtension|get#tearOffGetterOptional::T*>(#this);
+static method GenericExtension|get#tearOffGetterNamed<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#tearOffGetterNamed::T*>* #this) → dynamic
+  return self::GenericExtension|get#writeSetterNamed<self::GenericExtension|get#tearOffGetterNamed::T*>(#this);
+static method GenericExtension|get#tearOffGetterGenericRequired<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#tearOffGetterGenericRequired::T*>* #this) → dynamic
+  return self::GenericExtension|get#genericWriteSetterRequired<self::GenericExtension|get#tearOffGetterGenericRequired::T*>(#this);
+static method GenericExtension|get#tearOffGetterGenericOptional<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#tearOffGetterGenericOptional::T*>* #this) → dynamic
+  return self::GenericExtension|get#genericWriteSetterOptional<self::GenericExtension|get#tearOffGetterGenericOptional::T*>(#this);
+static method GenericExtension|get#tearOffGetterGenericNamed<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#tearOffGetterGenericNamed::T*>* #this) → dynamic
+  return self::GenericExtension|get#genericWriteSetterNamed<self::GenericExtension|get#tearOffGetterGenericNamed::T*>(#this);
+static method GenericExtension|invocations<T extends core::Object* = dynamic, S extends self::GenericExtension|invocations::T* = dynamic>(lowered final self::GenericClass<self::GenericExtension|invocations::T*>* #this, self::GenericExtension|invocations::S* value) → dynamic {
+  self::GenericExtension|readGetter<self::GenericExtension|invocations::T*>(#this);
+  self::GenericExtension|writeSetterRequired<self::GenericExtension|invocations::T*>(#this, value);
+  self::GenericExtension|writeSetterOptional<self::GenericExtension|invocations::T*>(#this);
+  self::GenericExtension|writeSetterOptional<self::GenericExtension|invocations::T*>(#this, value);
+  self::GenericExtension|writeSetterNamed<self::GenericExtension|invocations::T*>(#this);
+  self::GenericExtension|writeSetterNamed<self::GenericExtension|invocations::T*>(#this, value: value);
+  self::GenericExtension|genericWriteSetterRequired<self::GenericExtension|invocations::T*, self::GenericExtension|invocations::S*>(#this, value);
+  self::GenericExtension|genericWriteSetterRequired<self::GenericExtension|invocations::T*, self::GenericExtension|invocations::T*>(#this, value);
+  self::GenericExtension|genericWriteSetterRequired<self::GenericExtension|invocations::T*, self::GenericExtension|invocations::S*>(#this, value);
+  self::GenericExtension|genericWriteSetterOptional<self::GenericExtension|invocations::T*, self::GenericExtension|invocations::T*>(#this);
+  self::GenericExtension|genericWriteSetterOptional<self::GenericExtension|invocations::T*, self::GenericExtension|invocations::T*>(#this);
+  self::GenericExtension|genericWriteSetterOptional<self::GenericExtension|invocations::T*, self::GenericExtension|invocations::S*>(#this);
+  self::GenericExtension|genericWriteSetterOptional<self::GenericExtension|invocations::T*, self::GenericExtension|invocations::S*>(#this, value);
+  self::GenericExtension|genericWriteSetterOptional<self::GenericExtension|invocations::T*, self::GenericExtension|invocations::T*>(#this, value);
+  self::GenericExtension|genericWriteSetterOptional<self::GenericExtension|invocations::T*, self::GenericExtension|invocations::S*>(#this, value);
+  self::GenericExtension|genericWriteSetterNamed<self::GenericExtension|invocations::T*, self::GenericExtension|invocations::T*>(#this);
+  self::GenericExtension|genericWriteSetterNamed<self::GenericExtension|invocations::T*, self::GenericExtension|invocations::T*>(#this);
+  self::GenericExtension|genericWriteSetterNamed<self::GenericExtension|invocations::T*, self::GenericExtension|invocations::S*>(#this);
+  self::GenericExtension|genericWriteSetterNamed<self::GenericExtension|invocations::T*, self::GenericExtension|invocations::S*>(#this, value: value);
+  self::GenericExtension|genericWriteSetterNamed<self::GenericExtension|invocations::T*, self::GenericExtension|invocations::T*>(#this, value: value);
+  self::GenericExtension|genericWriteSetterNamed<self::GenericExtension|invocations::T*, self::GenericExtension|invocations::S*>(#this, value: value);
+}
+static method GenericExtension|get#invocations<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#invocations::T*>* #this) → <S extends self::GenericExtension|get#invocations::T* = dynamic>(S*) →* dynamic
+  return <S extends self::GenericExtension|get#invocations::T* = dynamic>(S* value) → dynamic => self::GenericExtension|invocations<self::GenericExtension|get#invocations::T*, S*>(#this, value);
+static method GenericExtension|tearOffs<T extends core::Object* = dynamic, S extends self::GenericExtension|tearOffs::T* = dynamic>(lowered final self::GenericClass<self::GenericExtension|tearOffs::T*>* #this, self::GenericExtension|tearOffs::S* value) → dynamic {
+  () →* self::GenericExtension|tearOffs::T* tearOffNoArgs = self::GenericExtension|get#readGetter<self::GenericExtension|tearOffs::T*>(#this);
+  tearOffNoArgs(){() →* self::GenericExtension|tearOffs::T*};
+  (self::GenericExtension|tearOffs::T*) →* dynamic tearOffRequired = self::GenericExtension|get#writeSetterRequired<self::GenericExtension|tearOffs::T*>(#this);
+  tearOffRequired(value){(self::GenericExtension|tearOffs::T*) →* dynamic};
+  ([self::GenericExtension|tearOffs::T*]) →* dynamic tearOffOptional = self::GenericExtension|get#writeSetterOptional<self::GenericExtension|tearOffs::T*>(#this);
+  tearOffOptional(){([self::GenericExtension|tearOffs::T*]) →* dynamic};
+  tearOffOptional(value){([self::GenericExtension|tearOffs::T*]) →* dynamic};
+  ({value: self::GenericExtension|tearOffs::T*}) →* dynamic tearOffNamed = self::GenericExtension|get#writeSetterNamed<self::GenericExtension|tearOffs::T*>(#this);
+  tearOffNamed(){({value: self::GenericExtension|tearOffs::T*}) →* dynamic};
+  tearOffNamed(value: value){({value: self::GenericExtension|tearOffs::T*}) →* dynamic};
+  <S extends self::GenericExtension|tearOffs::T* = dynamic>(S*) →* dynamic genericTearOffRequired = self::GenericExtension|get#genericWriteSetterRequired<self::GenericExtension|tearOffs::T*>(#this);
+  genericTearOffRequired<self::GenericExtension|tearOffs::S*>(value){(self::GenericExtension|tearOffs::S*) →* dynamic};
+  genericTearOffRequired<self::GenericExtension|tearOffs::T*>(value){(self::GenericExtension|tearOffs::T*) →* dynamic};
+  genericTearOffRequired<self::GenericExtension|tearOffs::S*>(value){(self::GenericExtension|tearOffs::S*) →* dynamic};
+  <S extends self::GenericExtension|tearOffs::T* = dynamic>([S*]) →* dynamic genericTearOffOptional = self::GenericExtension|get#genericWriteSetterOptional<self::GenericExtension|tearOffs::T*>(#this);
+  genericTearOffOptional<self::GenericExtension|tearOffs::T*>(){([self::GenericExtension|tearOffs::T*]) →* dynamic};
+  genericTearOffOptional<self::GenericExtension|tearOffs::T*>(){([self::GenericExtension|tearOffs::T*]) →* dynamic};
+  genericTearOffOptional<self::GenericExtension|tearOffs::S*>(){([self::GenericExtension|tearOffs::S*]) →* dynamic};
+  genericTearOffOptional<self::GenericExtension|tearOffs::S*>(value){([self::GenericExtension|tearOffs::S*]) →* dynamic};
+  genericTearOffOptional<self::GenericExtension|tearOffs::T*>(value){([self::GenericExtension|tearOffs::T*]) →* dynamic};
+  genericTearOffOptional<self::GenericExtension|tearOffs::S*>(value){([self::GenericExtension|tearOffs::S*]) →* dynamic};
+  <S extends self::GenericExtension|tearOffs::T* = dynamic>({value: S*}) →* dynamic genericTearOffNamed = self::GenericExtension|get#genericWriteSetterNamed<self::GenericExtension|tearOffs::T*>(#this);
+  genericTearOffNamed<self::GenericExtension|tearOffs::T*>(){({value: self::GenericExtension|tearOffs::T*}) →* dynamic};
+  genericTearOffNamed<self::GenericExtension|tearOffs::T*>(){({value: self::GenericExtension|tearOffs::T*}) →* dynamic};
+  genericTearOffNamed<self::GenericExtension|tearOffs::S*>(){({value: self::GenericExtension|tearOffs::S*}) →* dynamic};
+  genericTearOffNamed<self::GenericExtension|tearOffs::S*>(value: value){({value: self::GenericExtension|tearOffs::S*}) →* dynamic};
+  genericTearOffNamed<self::GenericExtension|tearOffs::T*>(value: value){({value: self::GenericExtension|tearOffs::T*}) →* dynamic};
+  genericTearOffNamed<self::GenericExtension|tearOffs::S*>(value: value){({value: self::GenericExtension|tearOffs::S*}) →* dynamic};
+}
+static method GenericExtension|get#tearOffs<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#tearOffs::T*>* #this) → <S extends self::GenericExtension|get#tearOffs::T* = dynamic>(S*) →* dynamic
+  return <S extends self::GenericExtension|get#tearOffs::T* = dynamic>(S* value) → dynamic => self::GenericExtension|tearOffs<self::GenericExtension|get#tearOffs::T*, S*>(#this, value);
+static method GenericExtension|getterCalls<T extends core::Object* = dynamic, S extends self::GenericExtension|getterCalls::T* = dynamic>(lowered final self::GenericClass<self::GenericExtension|getterCalls::T*>* #this, self::GenericExtension|getterCalls::S* value) → dynamic {
+  self::GenericExtension|get#tearOffGetterNoArgs<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call();
+  self::GenericExtension|get#tearOffGetterRequired<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call(value);
+  self::GenericExtension|get#tearOffGetterOptional<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call();
+  self::GenericExtension|get#tearOffGetterOptional<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call(value);
+  self::GenericExtension|get#tearOffGetterNamed<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call();
+  self::GenericExtension|get#tearOffGetterNamed<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call(value: value);
+  self::GenericExtension|get#tearOffGetterGenericRequired<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call(value);
+  self::GenericExtension|get#tearOffGetterGenericRequired<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call<self::GenericExtension|getterCalls::T*>(value);
+  self::GenericExtension|get#tearOffGetterGenericRequired<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call<self::GenericExtension|getterCalls::S*>(value);
+  self::GenericExtension|get#tearOffGetterGenericOptional<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call();
+  self::GenericExtension|get#tearOffGetterGenericOptional<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call<self::GenericExtension|getterCalls::T*>();
+  self::GenericExtension|get#tearOffGetterGenericOptional<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call<self::GenericExtension|getterCalls::S*>();
+  self::GenericExtension|get#tearOffGetterGenericOptional<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call(value);
+  self::GenericExtension|get#tearOffGetterGenericOptional<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call<self::GenericExtension|getterCalls::T*>(value);
+  self::GenericExtension|get#tearOffGetterGenericOptional<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call<self::GenericExtension|getterCalls::S*>(value);
+  self::GenericExtension|get#tearOffGetterGenericNamed<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call();
+  self::GenericExtension|get#tearOffGetterGenericNamed<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call<self::GenericExtension|getterCalls::T*>();
+  self::GenericExtension|get#tearOffGetterGenericNamed<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call<self::GenericExtension|getterCalls::S*>();
+  self::GenericExtension|get#tearOffGetterGenericNamed<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call(value: value);
+  self::GenericExtension|get#tearOffGetterGenericNamed<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call<self::GenericExtension|getterCalls::T*>(value: value);
+  self::GenericExtension|get#tearOffGetterGenericNamed<self::GenericExtension|getterCalls::T*>(#this){dynamic}.call<self::GenericExtension|getterCalls::S*>(value: value);
+}
+static method GenericExtension|get#getterCalls<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#getterCalls::T*>* #this) → <S extends self::GenericExtension|get#getterCalls::T* = dynamic>(S*) →* dynamic
+  return <S extends self::GenericExtension|get#getterCalls::T* = dynamic>(S* value) → dynamic => self::GenericExtension|getterCalls<self::GenericExtension|get#getterCalls::T*, S*>(#this, value);
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/extensions/direct_static_access.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/direct_static_access.dart.weak.modular.expect
new file mode 100644
index 0000000..942973c
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/direct_static_access.dart.weak.modular.expect
@@ -0,0 +1,242 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class<T extends core::Object* = dynamic> extends core::Object {
+  static field dynamic field = null;
+  synthetic constructor •() → self::Class<self::Class::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension<T extends core::Object* = dynamic> on self::Class<T*>* {
+  static get property = get self::Extension|property;
+  static field field = self::Extension|field;
+  static method readGetter = self::Extension|readGetter;
+  static method writeSetterRequired = self::Extension|writeSetterRequired;
+  static method writeSetterOptional = self::Extension|writeSetterOptional;
+  static method writeSetterNamed = self::Extension|writeSetterNamed;
+  static method genericWriteSetterRequired = self::Extension|genericWriteSetterRequired;
+  static method genericWriteSetterOptional = self::Extension|genericWriteSetterOptional;
+  static method genericWriteSetterNamed = self::Extension|genericWriteSetterNamed;
+  static get tearOffGetterNoArgs = get self::Extension|tearOffGetterNoArgs;
+  static get tearOffGetterRequired = get self::Extension|tearOffGetterRequired;
+  static get tearOffGetterOptional = get self::Extension|tearOffGetterOptional;
+  static get tearOffGetterNamed = get self::Extension|tearOffGetterNamed;
+  static get tearOffGetterGenericRequired = get self::Extension|tearOffGetterGenericRequired;
+  static get tearOffGetterGenericOptional = get self::Extension|tearOffGetterGenericOptional;
+  static get tearOffGetterGenericNamed = get self::Extension|tearOffGetterGenericNamed;
+  static method invocationsFromStaticContext = self::Extension|invocationsFromStaticContext;
+  static method tearOffsFromStaticContext = self::Extension|tearOffsFromStaticContext;
+  static method fieldAccessFromStaticContext = self::Extension|fieldAccessFromStaticContext;
+  static method getterCallsFromStaticContext = self::Extension|getterCallsFromStaticContext;
+  method invocationsFromInstanceContext = self::Extension|invocationsFromInstanceContext;
+  tearoff invocationsFromInstanceContext = self::Extension|get#invocationsFromInstanceContext;
+  method tearOffsFromInstanceContext = self::Extension|tearOffsFromInstanceContext;
+  tearoff tearOffsFromInstanceContext = self::Extension|get#tearOffsFromInstanceContext;
+  method fieldAccessFromInstanceContext = self::Extension|fieldAccessFromInstanceContext;
+  tearoff fieldAccessFromInstanceContext = self::Extension|get#fieldAccessFromInstanceContext;
+  method getterCallsFromInstanceContext = self::Extension|getterCallsFromInstanceContext;
+  tearoff getterCallsFromInstanceContext = self::Extension|get#getterCallsFromInstanceContext;
+  static set property = set self::Extension|property;
+}
+static field dynamic Extension|field;
+static get Extension|property() → dynamic
+  return self::Class::field;
+static set Extension|property(dynamic value) → void {
+  self::Class::field = value;
+}
+static method Extension|readGetter() → dynamic {
+  return self::Extension|property;
+}
+static method Extension|writeSetterRequired(dynamic value) → dynamic {
+  self::Extension|property = value;
+}
+static method Extension|writeSetterOptional([dynamic value = #C1]) → dynamic {
+  self::Extension|property = value;
+}
+static method Extension|writeSetterNamed({dynamic value = #C1}) → dynamic {
+  self::Extension|property = value;
+}
+static method Extension|genericWriteSetterRequired<S extends core::Object* = dynamic>(self::Extension|genericWriteSetterRequired::S* value) → dynamic {
+  self::Extension|property = value;
+}
+static method Extension|genericWriteSetterOptional<S extends core::Object* = dynamic>([self::Extension|genericWriteSetterOptional::S* value = #C1]) → dynamic {
+  self::Extension|property = value;
+}
+static method Extension|genericWriteSetterNamed<S extends core::Object* = dynamic>({self::Extension|genericWriteSetterNamed::S* value = #C1}) → dynamic {
+  self::Extension|property = value;
+}
+static get Extension|tearOffGetterNoArgs() → dynamic
+  return #C2;
+static get Extension|tearOffGetterRequired() → dynamic
+  return #C3;
+static get Extension|tearOffGetterOptional() → dynamic
+  return #C4;
+static get Extension|tearOffGetterNamed() → dynamic
+  return #C5;
+static get Extension|tearOffGetterGenericRequired() → dynamic
+  return #C6;
+static get Extension|tearOffGetterGenericOptional() → dynamic
+  return #C7;
+static get Extension|tearOffGetterGenericNamed() → dynamic
+  return #C8;
+static method Extension|invocationsFromStaticContext(core::int* value) → dynamic {
+  self::Extension|readGetter();
+  self::Extension|writeSetterRequired(value);
+  self::Extension|writeSetterOptional();
+  self::Extension|writeSetterOptional(value);
+  self::Extension|writeSetterNamed();
+  self::Extension|writeSetterNamed(value: value);
+  self::Extension|genericWriteSetterRequired<core::int*>(value);
+  self::Extension|genericWriteSetterRequired<core::int*>(value);
+  self::Extension|genericWriteSetterOptional<dynamic>();
+  self::Extension|genericWriteSetterOptional<core::int*>();
+  self::Extension|genericWriteSetterOptional<core::int*>(value);
+  self::Extension|genericWriteSetterOptional<core::int*>(value);
+  self::Extension|genericWriteSetterNamed<dynamic>();
+  self::Extension|genericWriteSetterNamed<core::int*>();
+  self::Extension|genericWriteSetterNamed<core::int*>(value: value);
+  self::Extension|genericWriteSetterNamed<core::int*>(value: value);
+}
+static method Extension|tearOffsFromStaticContext(core::int* value) → dynamic {
+  () →* dynamic tearOffNoArgs = #C2;
+  tearOffNoArgs(){() →* dynamic};
+  (dynamic) →* dynamic tearOffRequired = #C3;
+  tearOffRequired(value){(dynamic) →* dynamic};
+  ([dynamic]) →* dynamic tearOffOptional = #C4;
+  tearOffOptional(){([dynamic]) →* dynamic};
+  tearOffOptional(value){([dynamic]) →* dynamic};
+  ({value: dynamic}) →* dynamic tearOffNamed = #C5;
+  tearOffNamed(){({value: dynamic}) →* dynamic};
+  tearOffNamed(value: value){({value: dynamic}) →* dynamic};
+  <S extends core::Object* = dynamic>(S*) →* dynamic tearOffGenericRequired = #C6;
+  tearOffGenericRequired<core::int*>(value){(core::int*) →* dynamic};
+  tearOffGenericRequired<core::int*>(value){(core::int*) →* dynamic};
+  <S extends core::Object* = dynamic>([S*]) →* dynamic tearOffGenericOptional = #C7;
+  tearOffGenericOptional<dynamic>(){([dynamic]) →* dynamic};
+  tearOffGenericOptional<core::int*>(){([core::int*]) →* dynamic};
+  tearOffGenericOptional<core::int*>(value){([core::int*]) →* dynamic};
+  tearOffGenericOptional<core::int*>(value){([core::int*]) →* dynamic};
+  <S extends core::Object* = dynamic>({value: S*}) →* dynamic tearOffGenericNamed = #C8;
+  tearOffGenericNamed<dynamic>(){({value: dynamic}) →* dynamic};
+  tearOffGenericNamed<core::int*>(){({value: core::int*}) →* dynamic};
+  tearOffGenericNamed<core::int*>(value: value){({value: core::int*}) →* dynamic};
+  tearOffGenericNamed<core::int*>(value: value){({value: core::int*}) →* dynamic};
+}
+static method Extension|fieldAccessFromStaticContext() → dynamic {
+  self::Extension|field = self::Extension|property;
+  self::Extension|property = self::Extension|field;
+}
+static method Extension|getterCallsFromStaticContext(core::int* value) → dynamic {
+  self::Extension|tearOffGetterNoArgs{dynamic}.call();
+  self::Extension|tearOffGetterRequired{dynamic}.call(value);
+  self::Extension|tearOffGetterOptional{dynamic}.call();
+  self::Extension|tearOffGetterOptional{dynamic}.call(value);
+  self::Extension|tearOffGetterNamed{dynamic}.call();
+  self::Extension|tearOffGetterNamed{dynamic}.call(value: value);
+  self::Extension|tearOffGetterGenericRequired{dynamic}.call(value);
+  self::Extension|tearOffGetterGenericRequired{dynamic}.call<core::int*>(value);
+  self::Extension|tearOffGetterGenericOptional{dynamic}.call();
+  self::Extension|tearOffGetterGenericOptional{dynamic}.call<core::int*>();
+  self::Extension|tearOffGetterGenericOptional{dynamic}.call(value);
+  self::Extension|tearOffGetterGenericOptional{dynamic}.call<core::int*>(value);
+  self::Extension|tearOffGetterGenericNamed{dynamic}.call();
+  self::Extension|tearOffGetterGenericNamed{dynamic}.call<core::int*>();
+  self::Extension|tearOffGetterGenericNamed{dynamic}.call(value: value);
+  self::Extension|tearOffGetterGenericNamed{dynamic}.call<core::int*>(value: value);
+}
+static method Extension|invocationsFromInstanceContext<T extends core::Object* = dynamic>(lowered final self::Class<self::Extension|invocationsFromInstanceContext::T*>* #this, self::Extension|invocationsFromInstanceContext::T* value) → dynamic {
+  self::Extension|readGetter();
+  self::Extension|writeSetterRequired(value);
+  self::Extension|writeSetterOptional();
+  self::Extension|writeSetterOptional(value);
+  self::Extension|writeSetterNamed();
+  self::Extension|writeSetterNamed(value: value);
+  self::Extension|genericWriteSetterRequired<self::Extension|invocationsFromInstanceContext::T*>(value);
+  self::Extension|genericWriteSetterRequired<self::Extension|invocationsFromInstanceContext::T*>(value);
+  self::Extension|genericWriteSetterOptional<dynamic>();
+  self::Extension|genericWriteSetterOptional<self::Extension|invocationsFromInstanceContext::T*>();
+  self::Extension|genericWriteSetterOptional<self::Extension|invocationsFromInstanceContext::T*>(value);
+  self::Extension|genericWriteSetterOptional<self::Extension|invocationsFromInstanceContext::T*>(value);
+  self::Extension|genericWriteSetterNamed<dynamic>();
+  self::Extension|genericWriteSetterNamed<self::Extension|invocationsFromInstanceContext::T*>();
+  self::Extension|genericWriteSetterNamed<self::Extension|invocationsFromInstanceContext::T*>(value: value);
+  self::Extension|genericWriteSetterNamed<self::Extension|invocationsFromInstanceContext::T*>(value: value);
+}
+static method Extension|get#invocationsFromInstanceContext<T extends core::Object* = dynamic>(lowered final self::Class<self::Extension|get#invocationsFromInstanceContext::T*>* #this) → (self::Extension|get#invocationsFromInstanceContext::T*) →* dynamic
+  return (self::Extension|get#invocationsFromInstanceContext::T* value) → dynamic => self::Extension|invocationsFromInstanceContext<self::Extension|get#invocationsFromInstanceContext::T*>(#this, value);
+static method Extension|tearOffsFromInstanceContext<T extends core::Object* = dynamic>(lowered final self::Class<self::Extension|tearOffsFromInstanceContext::T*>* #this, self::Extension|tearOffsFromInstanceContext::T* value) → dynamic {
+  () →* dynamic tearOffNoArgs = #C2;
+  tearOffNoArgs(){() →* dynamic};
+  (dynamic) →* dynamic tearOffRequired = #C3;
+  tearOffRequired(value){(dynamic) →* dynamic};
+  ([dynamic]) →* dynamic tearOffOptional = #C4;
+  tearOffOptional(){([dynamic]) →* dynamic};
+  tearOffOptional(value){([dynamic]) →* dynamic};
+  ({value: dynamic}) →* dynamic tearOffNamed = #C5;
+  tearOffNamed(){({value: dynamic}) →* dynamic};
+  tearOffNamed(value: value){({value: dynamic}) →* dynamic};
+  <S extends core::Object* = dynamic>(S*) →* dynamic tearOffGenericRequired = #C6;
+  tearOffGenericRequired<self::Extension|tearOffsFromInstanceContext::T*>(value){(self::Extension|tearOffsFromInstanceContext::T*) →* dynamic};
+  tearOffGenericRequired<self::Extension|tearOffsFromInstanceContext::T*>(value){(self::Extension|tearOffsFromInstanceContext::T*) →* dynamic};
+  <S extends core::Object* = dynamic>([S*]) →* dynamic tearOffGenericOptional = #C7;
+  tearOffGenericOptional<dynamic>(){([dynamic]) →* dynamic};
+  tearOffGenericOptional<self::Extension|tearOffsFromInstanceContext::T*>(){([self::Extension|tearOffsFromInstanceContext::T*]) →* dynamic};
+  tearOffGenericOptional<self::Extension|tearOffsFromInstanceContext::T*>(value){([self::Extension|tearOffsFromInstanceContext::T*]) →* dynamic};
+  tearOffGenericOptional<self::Extension|tearOffsFromInstanceContext::T*>(value){([self::Extension|tearOffsFromInstanceContext::T*]) →* dynamic};
+  <S extends core::Object* = dynamic>({value: S*}) →* dynamic tearOffGenericNamed = #C8;
+  tearOffGenericNamed<dynamic>(){({value: dynamic}) →* dynamic};
+  tearOffGenericNamed<self::Extension|tearOffsFromInstanceContext::T*>(){({value: self::Extension|tearOffsFromInstanceContext::T*}) →* dynamic};
+  tearOffGenericNamed<self::Extension|tearOffsFromInstanceContext::T*>(value: value){({value: self::Extension|tearOffsFromInstanceContext::T*}) →* dynamic};
+  tearOffGenericNamed<self::Extension|tearOffsFromInstanceContext::T*>(value: value){({value: self::Extension|tearOffsFromInstanceContext::T*}) →* dynamic};
+}
+static method Extension|get#tearOffsFromInstanceContext<T extends core::Object* = dynamic>(lowered final self::Class<self::Extension|get#tearOffsFromInstanceContext::T*>* #this) → (self::Extension|get#tearOffsFromInstanceContext::T*) →* dynamic
+  return (self::Extension|get#tearOffsFromInstanceContext::T* value) → dynamic => self::Extension|tearOffsFromInstanceContext<self::Extension|get#tearOffsFromInstanceContext::T*>(#this, value);
+static method Extension|fieldAccessFromInstanceContext<T extends core::Object* = dynamic>(lowered final self::Class<self::Extension|fieldAccessFromInstanceContext::T*>* #this) → dynamic {
+  self::Extension|field = self::Extension|property;
+  self::Extension|property = self::Extension|field;
+}
+static method Extension|get#fieldAccessFromInstanceContext<T extends core::Object* = dynamic>(lowered final self::Class<self::Extension|get#fieldAccessFromInstanceContext::T*>* #this) → () →* dynamic
+  return () → dynamic => self::Extension|fieldAccessFromInstanceContext<self::Extension|get#fieldAccessFromInstanceContext::T*>(#this);
+static method Extension|getterCallsFromInstanceContext<T extends core::Object* = dynamic>(lowered final self::Class<self::Extension|getterCallsFromInstanceContext::T*>* #this, self::Extension|getterCallsFromInstanceContext::T* value) → dynamic {
+  self::Extension|tearOffGetterNoArgs{dynamic}.call();
+  self::Extension|tearOffGetterRequired{dynamic}.call(value);
+  self::Extension|tearOffGetterOptional{dynamic}.call();
+  self::Extension|tearOffGetterOptional{dynamic}.call(value);
+  self::Extension|tearOffGetterNamed{dynamic}.call();
+  self::Extension|tearOffGetterNamed{dynamic}.call(value: value);
+  self::Extension|tearOffGetterGenericRequired{dynamic}.call(value);
+  self::Extension|tearOffGetterGenericRequired{dynamic}.call<self::Extension|getterCallsFromInstanceContext::T*>(value);
+  self::Extension|tearOffGetterGenericOptional{dynamic}.call();
+  self::Extension|tearOffGetterGenericOptional{dynamic}.call<self::Extension|getterCallsFromInstanceContext::T*>();
+  self::Extension|tearOffGetterGenericOptional{dynamic}.call(value);
+  self::Extension|tearOffGetterGenericOptional{dynamic}.call<self::Extension|getterCallsFromInstanceContext::T*>(value);
+  self::Extension|tearOffGetterGenericNamed{dynamic}.call();
+  self::Extension|tearOffGetterGenericNamed{dynamic}.call<self::Extension|getterCallsFromInstanceContext::T*>();
+  self::Extension|tearOffGetterGenericNamed{dynamic}.call(value: value);
+  self::Extension|tearOffGetterGenericNamed{dynamic}.call<self::Extension|getterCallsFromInstanceContext::T*>(value: value);
+}
+static method Extension|get#getterCallsFromInstanceContext<T extends core::Object* = dynamic>(lowered final self::Class<self::Extension|get#getterCallsFromInstanceContext::T*>* #this) → (self::Extension|get#getterCallsFromInstanceContext::T*) →* dynamic
+  return (self::Extension|get#getterCallsFromInstanceContext::T* value) → dynamic => self::Extension|getterCallsFromInstanceContext<self::Extension|get#getterCallsFromInstanceContext::T*>(#this, value);
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = static-tearoff self::Extension|readGetter
+  #C3 = static-tearoff self::Extension|writeSetterRequired
+  #C4 = static-tearoff self::Extension|writeSetterOptional
+  #C5 = static-tearoff self::Extension|writeSetterNamed
+  #C6 = static-tearoff self::Extension|genericWriteSetterRequired
+  #C7 = static-tearoff self::Extension|genericWriteSetterOptional
+  #C8 = static-tearoff self::Extension|genericWriteSetterNamed
+}
diff --git a/pkg/front_end/testcases/extensions/dynamic_invoke.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/dynamic_invoke.dart.weak.modular.expect
new file mode 100644
index 0000000..8289cb4
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/dynamic_invoke.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic
+    return 123;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension ClassExtension on self::Class* {
+  method method = self::ClassExtension|method;
+  tearoff method = self::ClassExtension|get#method;
+}
+extension Extension on dynamic {
+  method method = self::Extension|method;
+  tearoff method = self::Extension|get#method;
+}
+static method ClassExtension|method(lowered final self::Class* #this) → core::int*
+  return 42;
+static method ClassExtension|get#method(lowered final self::Class* #this) → () →* core::int*
+  return () → core::int* => self::ClassExtension|method(#this);
+static method Extension|method(lowered final dynamic #this) → core::int*
+  return 87;
+static method Extension|get#method(lowered final dynamic #this) → () →* core::int*
+  return () → core::int* => self::Extension|method(#this);
+static method main() → dynamic {
+  dynamic c0 = new self::Class::•();
+  core::Object* c1 = new self::Class::•();
+  self::Class* c2 = new self::Class::•();
+  self::expect(123, c0{dynamic}.method());
+  self::expect(87, self::Extension|method(c1));
+  self::expect(42, self::ClassExtension|method(c2));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/explicit_extension_access.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/explicit_extension_access.dart.weak.modular.expect
new file mode 100644
index 0000000..b2bd40c
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/explicit_extension_access.dart.weak.modular.expect
@@ -0,0 +1,93 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int* field1 = 42;
+  field core::int* field2 = 87;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension1 on self::Class* {
+  get field = self::Extension1|get#field;
+  method method = self::Extension1|method;
+  tearoff method = self::Extension1|get#method;
+  method genericMethod = self::Extension1|genericMethod;
+  tearoff genericMethod = self::Extension1|get#genericMethod;
+  set field = self::Extension1|set#field;
+}
+extension Extension2 on self::Class* {
+  get field = self::Extension2|get#field;
+  method method = self::Extension2|method;
+  tearoff method = self::Extension2|get#method;
+  method genericMethod = self::Extension2|genericMethod;
+  tearoff genericMethod = self::Extension2|get#genericMethod;
+  set field = self::Extension2|set#field;
+}
+static method Extension1|get#field(lowered final self::Class* #this) → core::int*
+  return #this.{self::Class::field1}{core::int*};
+static method Extension1|set#field(lowered final self::Class* #this, core::int* value) → void {
+  #this.{self::Class::field1} = value;
+}
+static method Extension1|method(lowered final self::Class* #this) → core::int*
+  return #this.{self::Class::field1}{core::int*};
+static method Extension1|get#method(lowered final self::Class* #this) → () →* core::int*
+  return () → core::int* => self::Extension1|method(#this);
+static method Extension1|genericMethod<T extends core::num*>(lowered final self::Class* #this, self::Extension1|genericMethod::T* t) → core::int*
+  return #this.{self::Class::field1}{core::int*}.{core::num::+}(t){(core::num*) →* core::num*} as{TypeError} core::int*;
+static method Extension1|get#genericMethod(lowered final self::Class* #this) → <T extends core::num*>(T*) →* core::int*
+  return <T extends core::num*>(T* t) → core::int* => self::Extension1|genericMethod<T*>(#this, t);
+static method Extension2|get#field(lowered final self::Class* #this) → core::int*
+  return #this.{self::Class::field2}{core::int*};
+static method Extension2|set#field(lowered final self::Class* #this, core::int* value) → void {
+  #this.{self::Class::field2} = value;
+}
+static method Extension2|method(lowered final self::Class* #this) → core::int*
+  return #this.{self::Class::field2}{core::int*};
+static method Extension2|get#method(lowered final self::Class* #this) → () →* core::int*
+  return () → core::int* => self::Extension2|method(#this);
+static method Extension2|genericMethod<T extends core::num*>(lowered final self::Class* #this, self::Extension2|genericMethod::T* t) → core::int*
+  return #this.{self::Class::field2}{core::int*}.{core::num::+}(t){(core::num*) →* core::num*} as{TypeError} core::int*;
+static method Extension2|get#genericMethod(lowered final self::Class* #this) → <T extends core::num*>(T*) →* core::int*
+  return <T extends core::num*>(T* t) → core::int* => self::Extension2|genericMethod<T*>(#this, t);
+static method main() → dynamic {
+  self::Class* c = new self::Class::•();
+  self::expect(42, self::Extension1|get#field(c));
+  self::expect(87, self::Extension2|get#field(c));
+  self::expect(42, self::Extension1|method(c));
+  self::expect(87, self::Extension2|method(c));
+  () →* core::int* tearOff1 = self::Extension1|get#method(c);
+  () →* core::int* tearOff2 = self::Extension2|get#method(c);
+  self::expect(42, tearOff1(){() →* core::int*});
+  self::expect(87, tearOff2(){() →* core::int*});
+  self::expect(52, self::Extension1|genericMethod<core::int*>(c, 10));
+  self::expect(97, self::Extension2|genericMethod<core::int*>(c, 10));
+  self::expect(52, self::Extension1|genericMethod<core::num*>(c, 10));
+  self::expect(97, self::Extension2|genericMethod<core::num*>(c, 10));
+  <T extends core::num*>(T*) →* core::int* genericTearOff1 = self::Extension1|get#genericMethod(c);
+  <T extends core::num*>(T*) →* core::int* genericTearOff2 = self::Extension2|get#genericMethod(c);
+  self::expect(52, genericTearOff1<core::int*>(10){(core::int*) →* core::int*});
+  self::expect(97, genericTearOff2<core::int*>(10){(core::int*) →* core::int*});
+  self::expect(52, genericTearOff1<core::num*>(10){(core::num*) →* core::int*});
+  self::expect(97, genericTearOff2<core::num*>(10){(core::num*) →* core::int*});
+  self::expect(23, let final self::Class* #t1 = c in let final core::int* #t2 = 23 in let final void #t3 = self::Extension1|set#field(#t1, #t2) in #t2);
+  self::expect(67, let final self::Class* #t4 = c in let final core::int* #t5 = 67 in let final void #t6 = self::Extension2|set#field(#t4, #t5) in #t5);
+  self::expect(23, self::Extension1|get#field(c));
+  self::expect(67, self::Extension2|get#field(c));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/explicit_extension_inference.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/explicit_extension_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..429ac83
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/explicit_extension_inference.dart.weak.modular.expect
@@ -0,0 +1,140 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class GenericClass<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::GenericClass<self::GenericClass::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension GenericExtension<T extends core::Object* = dynamic> on self::GenericClass<T*>* {
+  get property = self::GenericExtension|get#property;
+  method method = self::GenericExtension|method;
+  tearoff method = self::GenericExtension|get#method;
+  method genericMethod1 = self::GenericExtension|genericMethod1;
+  tearoff genericMethod1 = self::GenericExtension|get#genericMethod1;
+}
+static method GenericExtension|get#property<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#property::T*>* #this) → self::GenericExtension|get#property::T*
+  return null;
+static method GenericExtension|method<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|method::T*>* #this, self::GenericExtension|method::T* t) → self::GenericExtension|method::T*
+  return null;
+static method GenericExtension|get#method<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#method::T*>* #this) → (self::GenericExtension|get#method::T*) →* self::GenericExtension|get#method::T*
+  return (self::GenericExtension|get#method::T* t) → self::GenericExtension|get#method::T* => self::GenericExtension|method<self::GenericExtension|get#method::T*>(#this, t);
+static method GenericExtension|genericMethod1<T extends core::Object* = dynamic, S extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|genericMethod1::T*>* #this, self::GenericExtension|genericMethod1::S* s) → self::GenericExtension|genericMethod1::S*
+  return null;
+static method GenericExtension|get#genericMethod1<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#genericMethod1::T*>* #this) → <S extends core::Object* = dynamic>(S*) →* S*
+  return <S extends core::Object* = dynamic>(S* s) → S* => self::GenericExtension|genericMethod1<self::GenericExtension|get#genericMethod1::T*, S*>(#this, s);
+static method main() → dynamic {
+  self::A* aVariable;
+  self::C* cVariable;
+  self::GenericClass<self::A*>* aClass;
+  self::GenericClass<self::B*>* bClass;
+  self::GenericClass<self::C*>* cClass;
+  cVariable = self::GenericExtension|get#property<self::A*>(aClass) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|get#property<self::A*>(aClass) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|get#property<self::B*>(aClass as{TypeError} self::GenericClass<self::B*>*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|get#property<self::C*>(aClass as{TypeError} self::GenericClass<self::C*>*);
+  cVariable = self::GenericExtension|get#property<self::B*>(bClass) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|get#property<self::A*>(bClass) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|get#property<self::B*>(bClass) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|get#property<self::C*>(bClass as{TypeError} self::GenericClass<self::C*>*);
+  aVariable = self::GenericExtension|get#property<self::C*>(cClass);
+  aVariable = self::GenericExtension|get#property<self::A*>(cClass);
+  aVariable = self::GenericExtension|get#property<self::B*>(cClass);
+  aVariable = self::GenericExtension|get#property<self::C*>(cClass);
+  cVariable = self::GenericExtension|method<self::A*>(aClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|method<self::A*>(aClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|method<self::B*>(aClass as{TypeError} self::GenericClass<self::B*>*, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|method<self::C*>(aClass as{TypeError} self::GenericClass<self::C*>*, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|method<self::B*>(bClass, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|method<self::A*>(bClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|method<self::B*>(bClass, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|method<self::C*>(bClass as{TypeError} self::GenericClass<self::C*>*, aVariable as{TypeError} self::C*);
+  aVariable = self::GenericExtension|method<self::C*>(cClass, aVariable as{TypeError} self::C*);
+  aVariable = self::GenericExtension|method<self::A*>(cClass, aVariable);
+  aVariable = self::GenericExtension|method<self::B*>(cClass, aVariable as{TypeError} self::B*);
+  aVariable = self::GenericExtension|method<self::C*>(cClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::C*>(aClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::A*>(aClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::B*>(aClass, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::C*>(aClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::C*>(aClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::A*>(aClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::B*>(aClass, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::C*>(aClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::C*>(aClass as{TypeError} self::GenericClass<self::B*>*, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::A*>(aClass as{TypeError} self::GenericClass<self::B*>*, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::B*>(aClass as{TypeError} self::GenericClass<self::B*>*, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::C*>(aClass as{TypeError} self::GenericClass<self::B*>*, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::C*>(aClass as{TypeError} self::GenericClass<self::C*>*, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::A*>(aClass as{TypeError} self::GenericClass<self::C*>*, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::B*>(aClass as{TypeError} self::GenericClass<self::C*>*, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::C*>(aClass as{TypeError} self::GenericClass<self::C*>*, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::C*>(bClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::A*>(bClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::B*>(bClass, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::C*>(bClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::C*>(bClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::A*>(bClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::B*>(bClass, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::C*>(bClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::C*>(bClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::A*>(bClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::B*>(bClass, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::C*>(bClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::C*>(bClass as{TypeError} self::GenericClass<self::C*>*, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::A*>(bClass as{TypeError} self::GenericClass<self::C*>*, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::B*>(bClass as{TypeError} self::GenericClass<self::C*>*, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::C*>(bClass as{TypeError} self::GenericClass<self::C*>*, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::C*>(cClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::A*>(cClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::B*>(cClass, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::C*>(cClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::C*>(cClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::A*>(cClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::B*>(cClass, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::C*>(cClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::C*>(cClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::A*>(cClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::B*>(cClass, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::C*>(cClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::C*>(cClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::A*>(cClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::B*>(cClass, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::C*>(cClass, aVariable as{TypeError} self::C*);
+}
diff --git a/pkg/front_end/testcases/extensions/explicit_generic_extension_access.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/explicit_generic_extension_access.dart.weak.modular.expect
new file mode 100644
index 0000000..ad69a00
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/explicit_generic_extension_access.dart.weak.modular.expect
@@ -0,0 +1,134 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class<T extends core::num*> extends core::Object {
+  covariant-by-class field self::Class::T* field1;
+  covariant-by-class field self::Class::T* field2;
+  constructor •(self::Class::T* field1, self::Class::T* field2) → self::Class<self::Class::T*>*
+    : self::Class::field1 = field1, self::Class::field2 = field2, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension1<T extends core::num*> on self::Class<T*>* {
+  static field latestType = self::Extension1|latestType;
+  get field = self::Extension1|get#field;
+  method method = self::Extension1|method;
+  tearoff method = self::Extension1|get#method;
+  method genericMethod = self::Extension1|genericMethod;
+  tearoff genericMethod = self::Extension1|get#genericMethod;
+  set field = self::Extension1|set#field;
+}
+extension Extension2<T extends core::num*> on self::Class<T*>* {
+  get field = self::Extension2|get#field;
+  method method = self::Extension2|method;
+  tearoff method = self::Extension2|get#method;
+  method genericMethod = self::Extension2|genericMethod;
+  tearoff genericMethod = self::Extension2|get#genericMethod;
+  set field = self::Extension2|set#field;
+}
+static field core::String* Extension1|latestType;
+static method Extension1|get#field<T extends core::num*>(lowered final self::Class<self::Extension1|get#field::T*>* #this) → self::Extension1|get#field::T* {
+  self::Extension1|latestType = "${self::Extension1|get#field::T*}";
+  return #this.{self::Class::field1}{self::Extension1|get#field::T*};
+}
+static method Extension1|set#field<T extends core::num*>(lowered final self::Class<self::Extension1|set#field::T*>* #this, self::Extension1|set#field::T* value) → void {
+  self::Extension1|latestType = "${self::Extension1|set#field::T*}";
+  #this.{self::Class::field1} = value;
+}
+static method Extension1|method<T extends core::num*>(lowered final self::Class<self::Extension1|method::T*>* #this) → self::Extension1|method::T* {
+  self::Extension1|latestType = "${self::Extension1|method::T*}";
+  return #this.{self::Class::field1}{self::Extension1|method::T*};
+}
+static method Extension1|get#method<T extends core::num*>(lowered final self::Class<self::Extension1|get#method::T*>* #this) → () →* self::Extension1|get#method::T*
+  return () → self::Extension1|get#method::T* => self::Extension1|method<self::Extension1|get#method::T*>(#this);
+static method Extension1|genericMethod<T extends core::num*, S extends core::num*>(lowered final self::Class<self::Extension1|genericMethod::T*>* #this, self::Extension1|genericMethod::S* t) → self::Extension1|genericMethod::T* {
+  self::Extension1|latestType = "${self::Extension1|genericMethod::T*}:${self::Extension1|genericMethod::S*}";
+  return #this.{self::Class::field1}{self::Extension1|genericMethod::T*}.{core::num::+}(t){(core::num*) →* core::num*} as{TypeError} self::Extension1|genericMethod::T*;
+}
+static method Extension1|get#genericMethod<T extends core::num*>(lowered final self::Class<self::Extension1|get#genericMethod::T*>* #this) → <S extends core::num*>(S*) →* self::Extension1|get#genericMethod::T*
+  return <S extends core::num*>(S* t) → self::Extension1|get#genericMethod::T* => self::Extension1|genericMethod<self::Extension1|get#genericMethod::T*, S*>(#this, t);
+static method Extension2|get#field<T extends core::num*>(lowered final self::Class<self::Extension2|get#field::T*>* #this) → self::Extension2|get#field::T*
+  return #this.{self::Class::field2}{self::Extension2|get#field::T*};
+static method Extension2|set#field<T extends core::num*>(lowered final self::Class<self::Extension2|set#field::T*>* #this, self::Extension2|set#field::T* value) → void {
+  #this.{self::Class::field2} = value;
+}
+static method Extension2|method<T extends core::num*>(lowered final self::Class<self::Extension2|method::T*>* #this) → self::Extension2|method::T*
+  return #this.{self::Class::field2}{self::Extension2|method::T*};
+static method Extension2|get#method<T extends core::num*>(lowered final self::Class<self::Extension2|get#method::T*>* #this) → () →* self::Extension2|get#method::T*
+  return () → self::Extension2|get#method::T* => self::Extension2|method<self::Extension2|get#method::T*>(#this);
+static method Extension2|genericMethod<T extends core::num*, S extends core::num*>(lowered final self::Class<self::Extension2|genericMethod::T*>* #this, self::Extension2|genericMethod::S* t) → self::Extension2|genericMethod::T*
+  return #this.{self::Class::field2}{self::Extension2|genericMethod::T*}.{core::num::+}(t){(core::num*) →* core::num*} as{TypeError} self::Extension2|genericMethod::T*;
+static method Extension2|get#genericMethod<T extends core::num*>(lowered final self::Class<self::Extension2|get#genericMethod::T*>* #this) → <S extends core::num*>(S*) →* self::Extension2|get#genericMethod::T*
+  return <S extends core::num*>(S* t) → self::Extension2|get#genericMethod::T* => self::Extension2|genericMethod<self::Extension2|get#genericMethod::T*, S*>(#this, t);
+static method main() → dynamic {
+  self::Class<core::int*>* c = new self::Class::•<core::int*>(42, 87);
+  self::expect(42, self::Extension1|get#field<core::num*>(c));
+  self::expect("num", self::Extension1|latestType);
+  self::expect(42, self::Extension1|get#field<core::int*>(c));
+  self::expect("int", self::Extension1|latestType);
+  self::expect(87, self::Extension2|get#field<core::num*>(c));
+  self::expect(42, self::Extension1|method<core::num*>(c));
+  self::expect("num", self::Extension1|latestType);
+  self::expect(42, self::Extension1|method<core::int*>(c));
+  self::expect("int", self::Extension1|latestType);
+  self::expect(87, self::Extension2|method<core::num*>(c));
+  () →* core::num* tearOffNumber1 = self::Extension1|get#method<core::num*>(c);
+  () →* core::int* tearOffInteger1 = self::Extension1|get#method<core::int*>(c);
+  () →* core::num* tearOff2 = self::Extension2|get#method<core::num*>(c);
+  self::expect(42, tearOffNumber1(){() →* core::num*});
+  self::expect("num", self::Extension1|latestType);
+  self::expect(42, tearOffInteger1(){() →* core::int*});
+  self::expect("int", self::Extension1|latestType);
+  self::expect(87, tearOff2(){() →* core::num*});
+  self::expect(52, self::Extension1|genericMethod<core::num*, core::int*>(c, 10));
+  self::expect("num:int", self::Extension1|latestType);
+  self::expect(52, self::Extension1|genericMethod<core::int*, core::int*>(c, 10));
+  self::expect("int:int", self::Extension1|latestType);
+  self::expect(97, self::Extension2|genericMethod<core::num*, core::int*>(c, 10));
+  self::expect(52, self::Extension1|genericMethod<core::num*, core::num*>(c, 10));
+  self::expect("num:num", self::Extension1|latestType);
+  self::expect(52, self::Extension1|genericMethod<core::int*, core::num*>(c, 10));
+  self::expect("int:num", self::Extension1|latestType);
+  self::expect(97, self::Extension2|genericMethod<core::num*, core::num*>(c, 10));
+  self::expect(52, self::Extension1|genericMethod<core::int*, core::int*>(c, 10));
+  self::expect("int:int", self::Extension1|latestType);
+  self::expect(52, self::Extension1|genericMethod<core::int*, core::num*>(c, 10));
+  self::expect("int:num", self::Extension1|latestType);
+  self::expect(52, self::Extension1|genericMethod<core::int*, core::int*>(c, 10));
+  self::expect("int:int", self::Extension1|latestType);
+  <S extends core::num*>(S*) →* core::num* genericTearOffNumber1 = self::Extension1|get#genericMethod<core::num*>(c);
+  <S extends core::num*>(S*) →* core::int* genericTearOffInteger1 = self::Extension1|get#genericMethod<core::int*>(c);
+  <S extends core::num*>(S*) →* core::num* genericTearOff2 = self::Extension2|get#genericMethod<core::num*>(c);
+  self::expect(52, genericTearOffNumber1<core::int*>(10){(core::int*) →* core::num*});
+  self::expect("num:int", self::Extension1|latestType);
+  self::expect(52, genericTearOffInteger1<core::int*>(10){(core::int*) →* core::int*});
+  self::expect("int:int", self::Extension1|latestType);
+  self::expect(97, genericTearOff2<core::int*>(10){(core::int*) →* core::num*});
+  self::expect(52, genericTearOffNumber1<core::num*>(10){(core::num*) →* core::num*});
+  self::expect("num:num", self::Extension1|latestType);
+  self::expect(52, genericTearOffInteger1<core::num*>(10){(core::num*) →* core::int*});
+  self::expect("int:num", self::Extension1|latestType);
+  self::expect(97, genericTearOff2<core::num*>(10){(core::num*) →* core::num*});
+  self::expect(23, let final self::Class<core::int*>* #t1 = c in let final core::int* #t2 = 23 in let final void #t3 = self::Extension1|set#field<core::num*>(#t1, #t2) in #t2);
+  self::expect("num", self::Extension1|latestType);
+  self::expect(23, let final self::Class<core::int*>* #t4 = c in let final core::int* #t5 = 23 in let final void #t6 = self::Extension1|set#field<core::int*>(#t4, #t5) in #t5);
+  self::expect("int", self::Extension1|latestType);
+  self::expect(67, let final self::Class<core::int*>* #t7 = c in let final core::int* #t8 = 67 in let final void #t9 = self::Extension2|set#field<core::num*>(#t7, #t8) in #t8);
+  self::expect(23, self::Extension1|get#field<core::num*>(c));
+  self::expect(67, self::Extension2|get#field<core::num*>(c));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/explicit_invalid_access.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/explicit_invalid_access.dart.weak.modular.expect
new file mode 100644
index 0000000..f0bae7e
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/explicit_invalid_access.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/explicit_invalid_access.dart:10:3: Error: Explicit extension application cannot be used as an expression.
+//   Extension(c);
+//   ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/explicit_invalid_access.dart:11:3: Error: Explicit extension application cannot be a target for assignment.
+//   Extension(c) = 42;
+//   ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/explicit_invalid_access.dart:12:3: Error: Explicit extension application cannot be used as an expression.
+//   Extension(c) += 42;
+//   ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/explicit_invalid_access.dart:13:3: Error: Explicit extension application cannot be used as an expression.
+//   Extension(c)++;
+//   ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/explicit_invalid_access.dart:14:5: Error: Explicit extension application cannot be used as an expression.
+//   ++Extension(c);
+//     ^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+}
+static method errors(self::Class* c) → dynamic {
+  invalid-expression "pkg/front_end/testcases/extensions/explicit_invalid_access.dart:10:3: Error: Explicit extension application cannot be used as an expression.
+  Extension(c);
+  ^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/explicit_invalid_access.dart:11:3: Error: Explicit extension application cannot be a target for assignment.
+  Extension(c) = 42;
+  ^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/explicit_invalid_access.dart:12:3: Error: Explicit extension application cannot be used as an expression.
+  Extension(c) += 42;
+  ^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/explicit_invalid_access.dart:13:3: Error: Explicit extension application cannot be used as an expression.
+  Extension(c)++;
+  ^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/explicit_invalid_access.dart:14:5: Error: Explicit extension application cannot be used as an expression.
+  ++Extension(c);
+    ^^^^^^^^^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/explicit_this.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/explicit_this.dart.weak.modular.expect
new file mode 100644
index 0000000..9328ef6
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/explicit_this.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  field core::Object* field = null;
+  synthetic constructor •() → self::A1*
+    : super core::Object::•()
+    ;
+  method method1() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension A2 on self::A1* {
+  method method2 = self::A2|method2;
+  tearoff method2 = self::A2|get#method2;
+  method method3 = self::A2|method3;
+  tearoff method3 = self::A2|get#method3;
+  method method4 = self::A2|method4;
+  tearoff method4 = self::A2|get#method4;
+}
+static method A2|method2(lowered final self::A1* #this) → void
+  return #this.{self::A1::method1}(){() →* void};
+static method A2|get#method2(lowered final self::A1* #this) → () →* void
+  return () → void => self::A2|method2(#this);
+static method A2|method3(lowered final self::A1* #this) → core::Object*
+  return #this.{self::A1::field}{core::Object*};
+static method A2|get#method3(lowered final self::A1* #this) → () →* core::Object*
+  return () → core::Object* => self::A2|method3(#this);
+static method A2|method4(lowered final self::A1* #this, core::Object* o) → void {
+  #this.{self::A1::field} = o;
+}
+static method A2|get#method4(lowered final self::A1* #this) → (core::Object*) →* void
+  return (core::Object* o) → void => self::A2|method4(#this, o);
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/export_from_dill/main.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/export_from_dill/main.dart.weak.modular.expect
new file mode 100644
index 0000000..6a3bebc
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/export_from_dill/main.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library;
+import self as self;
+import "main_lib2.dart" as mai;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///main_lib1.dart";
+
+static method main() → dynamic {
+  mai::Extension|set#instanceProperty(0, mai::Extension|get#instanceProperty(1));
+  mai::Extension|instanceMethod(2);
+  mai::Extension|get#instanceMethod(3);
+  mai::Extension|staticField = #C1;
+  mai::Extension|set#instanceProperty(3, mai::Extension|staticFinalField);
+  mai::Extension|staticProperty = mai::Extension|staticProperty;
+  mai::Extension|staticMethod();
+  #C2;
+}
+
+constants  {
+  #C1 = 42
+  #C2 = static-tearoff mai::Extension|staticMethod
+}
diff --git a/pkg/front_end/testcases/extensions/export_twice.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/export_twice.dart.weak.modular.expect
new file mode 100644
index 0000000..d7eef99
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/export_twice.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library;
+import self as self;
+import "export_twice_lib1.dart" as exp;
+
+import "org-dartlang-testcase:///export_twice_lib1.dart";
+import "org-dartlang-testcase:///export_twice_lib2.dart";
+
+static method main() → dynamic {
+  exp::Extension|method(new exp::Class::•());
+}
+
+library;
+import self as exp;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → exp::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on exp::Class* {
+  method method = exp::Extension|method;
+  tearoff method = exp::Extension|get#method;
+}
+static method Extension|method(lowered final exp::Class* #this) → dynamic {}
+static method Extension|get#method(lowered final exp::Class* #this) → () →* dynamic
+  return () → dynamic => exp::Extension|method(#this);
+
+library;
+import self as self2;
+import "export_twice_lib1.dart" as exp;
+additionalExports = (exp::Extension)
+
+export "org-dartlang-testcase:///export_twice_lib1.dart" show Extension;
diff --git a/pkg/front_end/testcases/extensions/extension_call.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/extension_call.dart.weak.modular.expect
new file mode 100644
index 0000000..13106a6
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/extension_call.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::T*>*
+    : super core::Object::•()
+    ;
+  method method(covariant-by-class self::Class::T* a) → self::Class::T*
+    return a;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension<T extends core::Object* = dynamic> on self::Class<T*>* {
+  method call = self::Extension|call;
+  tearoff call = self::Extension|get#call;
+}
+static method Extension|call<T extends core::Object* = dynamic>(lowered final self::Class<self::Extension|call::T*>* #this, self::Extension|call::T* a) → self::Extension|call::T*
+  return #this.{self::Class::method}(a){(self::Extension|call::T*) →* self::Extension|call::T*};
+static method Extension|get#call<T extends core::Object* = dynamic>(lowered final self::Class<self::Extension|get#call::T*>* #this) → (self::Extension|get#call::T*) →* self::Extension|get#call::T*
+  return (self::Extension|get#call::T* a) → self::Extension|get#call::T* => self::Extension|call<self::Extension|get#call::T*>(#this, a);
+static method main() → dynamic {
+  self::Class<core::int*>* c = new self::Class::•<core::int*>();
+  self::expect(42, self::Extension|call<core::int*>(c, 42));
+  self::expect(87, self::Extension|call<core::int*>(c, 87));
+  self::expect(123, self::Extension|call<core::int*>(c, 123));
+  self::expect(42, self::Extension|call<core::int*>(c, 42));
+  self::expect(87, self::Extension|call<core::int*>(c, 87));
+  self::expect(123, self::Extension|call<core::int*>(c, 123));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/extension_constructor.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/extension_constructor.dart.weak.modular.expect
new file mode 100644
index 0000000..8400d5d
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/extension_constructor.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/extension_constructor.dart:8:3: Error: Extensions can't declare constructors.
+// Try removing the constructor declaration.
+//   Extension() {}
+//   ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_constructor.dart:9:3: Error: Extensions can't declare constructors.
+// Try removing the constructor declaration.
+//   Extension.named() {}
+//   ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_constructor.dart:10:3: Error: Extensions can't declare constructors.
+// Try removing the constructor declaration.
+//   factory Extension.fact() => null;
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_constructor.dart:11:3: Error: Extensions can't declare constructors.
+// Try removing the constructor declaration.
+//   factory Extension.redirect() = Extension;
+//   ^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+  method method = self::Extension|method;
+  tearoff method = self::Extension|get#method;
+}
+static method Extension|method(lowered final self::Class* #this) → dynamic {}
+static method Extension|get#method(lowered final self::Class* #this) → () →* dynamic
+  return () → dynamic => self::Extension|method(#this);
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/extension_field_with_type_parameter_usage.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/extension_field_with_type_parameter_usage.dart.weak.modular.expect
new file mode 100644
index 0000000..1539e4a
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/extension_field_with_type_parameter_usage.dart.weak.modular.expect
@@ -0,0 +1,79 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/extension_field_with_type_parameter_usage.dart:6:5: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   U field1 = null;
+//     ^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_field_with_type_parameter_usage.dart:7:8: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int? field2 = () { U x = null; return null; }();
+//        ^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_field_with_type_parameter_usage.dart:8:12: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   List<U>? field3 = null;
+//            ^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_field_with_type_parameter_usage.dart:9:18: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   U Function(U)? field4 = null;
+//                  ^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_field_with_type_parameter_usage.dart:10:30: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   List<U> Function(List<U>)? field5 = null;
+//                              ^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_field_with_type_parameter_usage.dart:11:8: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int? field6 = <E>() { E? x = null; return null; }<String>();
+//        ^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_field_with_type_parameter_usage.dart:12:8: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int? field7 = <E>() { E? x = null; return null; }<U>();
+//        ^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_field_with_type_parameter_usage.dart:13:8: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   Type field8 = U;
+//        ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+extension E<U extends core::Object? = dynamic> on core::String {
+  field field1 = self::E|field1;
+  field field2 = self::E|field2;
+  field field3 = self::E|field3;
+  field field4 = self::E|field4;
+  field field5 = self::E|field5;
+  field field6 = self::E|field6;
+  field field7 = self::E|field7;
+  field field8 = self::E|field8;
+}
+static field invalid-type E|field1 = null;
+static field core::int? E|field2 = (() → Null {
+  invalid-type x = null;
+  return null;
+})(){() → Null};
+static field core::List<invalid-type>? E|field3 = null;
+static field (invalid-type) →? invalid-type E|field4 = null;
+static field (core::List<invalid-type>) →? core::List<invalid-type> E|field5 = null;
+static field core::int? E|field6 = (<E extends core::Object? = dynamic>() → Null {
+  E? x = null;
+  return null;
+})<core::String>(){() → Null};
+static field core::int? E|field7 = (<E extends core::Object? = dynamic>() → Null {
+  E? x = null;
+  return null;
+})<invalid-type>(){() → Null};
+static field core::Type E|field8 = #C1;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = TypeLiteralConstant(invalid-type)
+}
diff --git a/pkg/front_end/testcases/extensions/extension_member_conflict.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/extension_member_conflict.dart.weak.modular.expect
new file mode 100644
index 0000000..fd72cf1
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/extension_member_conflict.dart.weak.modular.expect
@@ -0,0 +1,209 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:7:11: Error: 'duplicateInstanceGetter' is already declared in this scope.
+//   int get duplicateInstanceGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:6:11: Context: Previous declaration of 'duplicateInstanceGetter'.
+//   int get duplicateInstanceGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:10:12: Error: 'duplicateInstanceSetter' is already declared in this scope.
+//   void set duplicateInstanceSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:9:12: Context: Previous declaration of 'duplicateInstanceSetter'.
+//   void set duplicateInstanceSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:13:8: Error: 'duplicateInstanceMethod' is already declared in this scope.
+//   void duplicateInstanceMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:12:8: Context: Previous declaration of 'duplicateInstanceMethod'.
+//   void duplicateInstanceMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:16:14: Error: 'duplicateStaticField' is already declared in this scope.
+//   static int duplicateStaticField = 0;
+//              ^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:15:14: Context: Previous declaration of 'duplicateStaticField'.
+//   static int duplicateStaticField = 0;
+//              ^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:19:18: Error: 'duplicateStaticGetter' is already declared in this scope.
+//   static int get duplicateStaticGetter => 0;
+//                  ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:18:18: Context: Previous declaration of 'duplicateStaticGetter'.
+//   static int get duplicateStaticGetter => 0;
+//                  ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:22:19: Error: 'duplicateStaticSetter' is already declared in this scope.
+//   static void set duplicateStaticSetter(int value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:21:19: Context: Previous declaration of 'duplicateStaticSetter'.
+//   static void set duplicateStaticSetter(int value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:25:15: Error: 'duplicateStaticMethod' is already declared in this scope.
+//   static void duplicateStaticMethod() {}
+//               ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:24:15: Context: Previous declaration of 'duplicateStaticMethod'.
+//   static void duplicateStaticMethod() {}
+//               ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:28:11: Error: 'duplicateInstanceGetterPlusSetter' is already declared in this scope.
+//   int get duplicateInstanceGetterPlusSetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:27:11: Context: Previous declaration of 'duplicateInstanceGetterPlusSetter'.
+//   int get duplicateInstanceGetterPlusSetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:33:12: Error: 'duplicateInstanceSetterPlusGetter' is already declared in this scope.
+//   void set duplicateInstanceSetterPlusGetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:32:12: Context: Previous declaration of 'duplicateInstanceSetterPlusGetter'.
+//   void set duplicateInstanceSetterPlusGetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:36:11: Error: 'duplicateInstanceGetterAndSetter' is already declared in this scope.
+//   int get duplicateInstanceGetterAndSetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:35:11: Context: Previous declaration of 'duplicateInstanceGetterAndSetter'.
+//   int get duplicateInstanceGetterAndSetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:38:12: Error: 'duplicateInstanceGetterAndSetter' is already declared in this scope.
+//   void set duplicateInstanceGetterAndSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:37:12: Context: Previous declaration of 'duplicateInstanceGetterAndSetter'.
+//   void set duplicateInstanceGetterAndSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:41:18: Error: 'duplicateStaticGetterPlusSetter' is already declared in this scope.
+//   static int get duplicateStaticGetterPlusSetter => 0;
+//                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:40:18: Context: Previous declaration of 'duplicateStaticGetterPlusSetter'.
+//   static int get duplicateStaticGetterPlusSetter => 0;
+//                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:46:19: Error: 'duplicateStaticSetterPlusGetter' is already declared in this scope.
+//   static void set duplicateStaticSetterPlusGetter(int value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:45:19: Context: Previous declaration of 'duplicateStaticSetterPlusGetter'.
+//   static void set duplicateStaticSetterPlusGetter(int value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:49:18: Error: 'duplicateStaticGetterAndSetter' is already declared in this scope.
+//   static int get duplicateStaticGetterAndSetter => 0;
+//                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:48:18: Context: Previous declaration of 'duplicateStaticGetterAndSetter'.
+//   static int get duplicateStaticGetterAndSetter => 0;
+//                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:51:19: Error: 'duplicateStaticGetterAndSetter' is already declared in this scope.
+//   static void set duplicateStaticGetterAndSetter(int value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:50:19: Context: Previous declaration of 'duplicateStaticGetterAndSetter'.
+//   static void set duplicateStaticGetterAndSetter(int value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:60:14: Error: 'instanceGetterAndStaticField' is already declared in this scope.
+//   static int instanceGetterAndStaticField = 0;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:59:11: Context: Previous declaration of 'instanceGetterAndStaticField'.
+//   int get instanceGetterAndStaticField => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:63:20: Error: 'instanceGetterAndStaticField' is already declared in this scope.
+//   static final int instanceGetterAndStaticField = 0;
+//                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:60:14: Context: Previous declaration of 'instanceGetterAndStaticField'.
+//   static int instanceGetterAndStaticField = 0;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:54:19: Error: Conflicts with member 'instanceGetterAndStaticSetter'.
+//   static void set instanceGetterAndStaticSetter(int value) {}
+//                   ^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:53:11: Error: Conflicts with setter 'instanceGetterAndStaticSetter'.
+//   int get instanceGetterAndStaticSetter => 0;
+//           ^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:57:12: Error: Conflicts with member 'instanceSetterAndStaticGetter'.
+//   void set instanceSetterAndStaticGetter(int value) {}
+//            ^
+//
+// pkg/front_end/testcases/extensions/extension_member_conflict.dart:56:18: Error: Conflicts with setter 'instanceSetterAndStaticGetter'.
+//   static int get instanceSetterAndStaticGetter => 0;
+//                  ^
+//
+import self as self;
+import "dart:core" as core;
+
+extension Extension<T extends core::Object* = dynamic> on core::int* {
+  get duplicateInstanceGetter = self::Extension|get#duplicateInstanceGetter;
+  method duplicateInstanceMethod = self::Extension|duplicateInstanceMethod;
+  tearoff duplicateInstanceMethod = self::Extension|get#duplicateInstanceMethod;
+  static field duplicateStaticField = self::Extension|duplicateStaticField;
+  static get duplicateStaticGetter = get self::Extension|duplicateStaticGetter;
+  static method duplicateStaticMethod = self::Extension|duplicateStaticMethod;
+  get duplicateInstanceGetterPlusSetter = self::Extension|get#duplicateInstanceGetterPlusSetter;
+  get duplicateInstanceSetterPlusGetter = self::Extension|get#duplicateInstanceSetterPlusGetter;
+  get duplicateInstanceGetterAndSetter = self::Extension|get#duplicateInstanceGetterAndSetter;
+  static get duplicateStaticGetterPlusSetter = get self::Extension|duplicateStaticGetterPlusSetter;
+  static get duplicateStaticSetterPlusGetter = get self::Extension|duplicateStaticSetterPlusGetter;
+  static get duplicateStaticGetterAndSetter = get self::Extension|duplicateStaticGetterAndSetter;
+  get instanceGetterAndStaticSetter = self::Extension|get#instanceGetterAndStaticSetter;
+  static get instanceSetterAndStaticGetter = get self::Extension|instanceSetterAndStaticGetter;
+  get instanceGetterAndStaticField = self::Extension|get#instanceGetterAndStaticField;
+  set duplicateInstanceSetter = self::Extension|set#duplicateInstanceSetter;
+  static set duplicateStaticSetter = set self::Extension|duplicateStaticSetter;
+  set duplicateInstanceGetterPlusSetter = self::Extension|set#duplicateInstanceGetterPlusSetter;
+  set duplicateInstanceSetterPlusGetter = self::Extension|set#duplicateInstanceSetterPlusGetter;
+  set duplicateInstanceGetterAndSetter = self::Extension|set#duplicateInstanceGetterAndSetter;
+  static set duplicateStaticGetterPlusSetter = set self::Extension|duplicateStaticGetterPlusSetter;
+  static set duplicateStaticSetterPlusGetter = set self::Extension|duplicateStaticSetterPlusGetter;
+  static set duplicateStaticGetterAndSetter = set self::Extension|duplicateStaticGetterAndSetter;
+  static set instanceGetterAndStaticSetter = set self::Extension|instanceGetterAndStaticSetter;
+  set instanceSetterAndStaticGetter = self::Extension|set#instanceSetterAndStaticGetter;
+  set instanceSetterAndStaticField = self::Extension|set#instanceSetterAndStaticField;
+}
+static field core::int* Extension|duplicateStaticField;
+static method Extension|get#duplicateInstanceGetter<T extends core::Object* = dynamic>(lowered final core::int* #this) → core::int*
+  return 0;
+static method Extension|set#duplicateInstanceSetter<T extends core::Object* = dynamic>(lowered final core::int* #this, core::int* value) → void {}
+static method Extension|duplicateInstanceMethod<T extends core::Object* = dynamic>(lowered final core::int* #this) → void {}
+static method Extension|get#duplicateInstanceMethod<T extends core::Object* = dynamic>(lowered final core::int* #this) → () →* void
+  return () → void => self::Extension|duplicateInstanceMethod<self::Extension|get#duplicateInstanceMethod::T*>(#this);
+static get Extension|duplicateStaticGetter() → core::int*
+  return 0;
+static set Extension|duplicateStaticSetter(core::int* value) → void {}
+static method Extension|duplicateStaticMethod() → void {}
+static method Extension|get#duplicateInstanceGetterPlusSetter<T extends core::Object* = dynamic>(lowered final core::int* #this) → core::int*
+  return 0;
+static method Extension|set#duplicateInstanceGetterPlusSetter<T extends core::Object* = dynamic>(lowered final core::int* #this, core::int* value) → void {}
+static method Extension|get#duplicateInstanceSetterPlusGetter<T extends core::Object* = dynamic>(lowered final core::int* #this) → core::int*
+  return 0;
+static method Extension|set#duplicateInstanceSetterPlusGetter<T extends core::Object* = dynamic>(lowered final core::int* #this, core::int* value) → void {}
+static method Extension|get#duplicateInstanceGetterAndSetter<T extends core::Object* = dynamic>(lowered final core::int* #this) → core::int*
+  return 0;
+static method Extension|set#duplicateInstanceGetterAndSetter<T extends core::Object* = dynamic>(lowered final core::int* #this, core::int* value) → void {}
+static get Extension|duplicateStaticGetterPlusSetter() → core::int*
+  return 0;
+static set Extension|duplicateStaticGetterPlusSetter(core::int* value) → void {}
+static get Extension|duplicateStaticSetterPlusGetter() → core::int*
+  return 0;
+static set Extension|duplicateStaticSetterPlusGetter(core::int* value) → void {}
+static get Extension|duplicateStaticGetterAndSetter() → core::int*
+  return 0;
+static set Extension|duplicateStaticGetterAndSetter(core::int* value) → void {}
+static method Extension|get#instanceGetterAndStaticSetter<T extends core::Object* = dynamic>(lowered final core::int* #this) → core::int*
+  return 0;
+static set Extension|instanceGetterAndStaticSetter(core::int* value) → void {}
+static get Extension|instanceSetterAndStaticGetter() → core::int*
+  return 0;
+static method Extension|set#instanceSetterAndStaticGetter<T extends core::Object* = dynamic>(lowered final core::int* #this, core::int* value) → void {}
+static method Extension|get#instanceGetterAndStaticField<T extends core::Object* = dynamic>(lowered final core::int* #this) → core::int*
+  return 0;
+static method Extension|set#instanceSetterAndStaticField<T extends core::Object* = dynamic>(lowered final core::int* #this, core::int* value) → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/extension_methods.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/extension_methods.dart.weak.modular.expect
new file mode 100644
index 0000000..dd3ee97
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/extension_methods.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  get one() → core::int*
+    return 1;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension E on self::C* {
+  get two = self::E|get#two;
+}
+static method E|get#two(lowered final self::C* #this) → core::int*
+  return 2;
+static method main() → dynamic {
+  self::C* c = new self::C::•();
+  core::int* result = c.{self::C::one}{core::int*}.{core::num::+}(self::E|get#two(c)){(core::num*) →* core::int*};
+  exp::Expect::equals(result, 3);
+}
diff --git a/pkg/front_end/testcases/extensions/extension_setter.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/extension_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..049dae0
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/extension_setter.dart.weak.modular.expect
@@ -0,0 +1,223 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int* field = null;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class GenericClass<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::GenericClass<self::GenericClass::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+  get simpleSetter = self::Extension|get#simpleSetter;
+  get mutatingSetter = self::Extension|get#mutatingSetter;
+  get setterWithReturn = self::Extension|get#setterWithReturn;
+  get setterWithClosure = self::Extension|get#setterWithClosure;
+  method testInternal = self::Extension|testInternal;
+  tearoff testInternal = self::Extension|get#testInternal;
+  set simpleSetter = self::Extension|set#simpleSetter;
+  set mutatingSetter = self::Extension|set#mutatingSetter;
+  set setterWithReturn = self::Extension|set#setterWithReturn;
+  set setterWithClosure = self::Extension|set#setterWithClosure;
+}
+extension GenericExtension<T extends core::Object* = dynamic> on self::GenericClass<T*>* {
+  set setter = self::GenericExtension|set#setter;
+}
+static method Extension|get#simpleSetter(lowered final self::Class* #this) → core::int*
+  return #this.{self::Class::field}{core::int*};
+static method Extension|set#simpleSetter(lowered final self::Class* #this, core::int* value) → void {
+  #this.{self::Class::field} = value;
+}
+static method Extension|get#mutatingSetter(lowered final self::Class* #this) → core::int*
+  return #this.{self::Class::field}{core::int*};
+static method Extension|set#mutatingSetter(lowered final self::Class* #this, core::int* value) → void {
+  value = value.{core::num::+}(1){(core::num*) →* core::int*};
+  #this.{self::Class::field} = value;
+}
+static method Extension|get#setterWithReturn(lowered final self::Class* #this) → core::int*
+  return #this.{self::Class::field}{core::int*};
+static method Extension|set#setterWithReturn(lowered final self::Class* #this, core::int* value) → void {
+  if(value.{core::num::<}(0){(core::num*) →* core::bool*}) {
+    #this.{self::Class::field} = value.{core::int::unary-}(){() →* core::int*};
+    return;
+  }
+  #this.{self::Class::field} = value;
+}
+static method Extension|get#setterWithClosure(lowered final self::Class* #this) → core::int*
+  return #this.{self::Class::field}{core::int*};
+static method Extension|set#setterWithClosure(lowered final self::Class* #this, core::int* value) → void {
+  function abs(dynamic value) → dynamic {
+    return value{dynamic}.<(0) as{TypeError,ForDynamic} core::bool* ?{dynamic} value{dynamic}.unary-() : value;
+  }
+  #this.{self::Class::field} = abs(value){(dynamic) →* dynamic} as{TypeError,ForDynamic} core::int*;
+}
+static method Extension|testInternal(lowered final self::Class* #this) → dynamic {
+  self::expect(null, #this.{self::Class::field}{core::int*});
+  self::Extension|set#simpleSetter(#this, 0);
+  self::expect(0, #this.{self::Class::field}{core::int*});
+  self::expect(1, let final core::int* #t1 = 1 in let final void #t2 = self::Extension|set#simpleSetter(#this, #t1) in #t1);
+  self::Extension|set#mutatingSetter(#this, 0);
+  self::expect(1, #this.{self::Class::field}{core::int*});
+  self::expect(2, let final core::int* #t3 = 2 in let final void #t4 = self::Extension|set#mutatingSetter(#this, #t3) in #t3);
+  self::expect(3, #this.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithReturn(#this, 1);
+  self::expect(1, #this.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithReturn(#this, 2.{core::int::unary-}(){() →* core::int*});
+  self::expect(2, #this.{self::Class::field}{core::int*});
+  self::expect(3, let final core::int* #t5 = 3 in let final void #t6 = self::Extension|set#setterWithReturn(#this, #t5) in #t5);
+  self::expect(3, #this.{self::Class::field}{core::int*});
+  self::expect(4.{core::int::unary-}(){() →* core::int*}, let final core::int* #t7 = 4.{core::int::unary-}(){() →* core::int*} in let final void #t8 = self::Extension|set#setterWithReturn(#this, #t7) in #t7);
+  self::expect(4, #this.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithClosure(#this, 1);
+  self::expect(1, #this.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithClosure(#this, 2.{core::int::unary-}(){() →* core::int*});
+  self::expect(2, #this.{self::Class::field}{core::int*});
+  self::expect(3, let final core::int* #t9 = 3 in let final void #t10 = self::Extension|set#setterWithClosure(#this, #t9) in #t9);
+  self::expect(3, #this.{self::Class::field}{core::int*});
+  self::expect(4.{core::int::unary-}(){() →* core::int*}, let final core::int* #t11 = 4.{core::int::unary-}(){() →* core::int*} in let final void #t12 = self::Extension|set#setterWithClosure(#this, #t11) in #t11);
+  self::expect(4, #this.{self::Class::field}{core::int*});
+}
+static method Extension|get#testInternal(lowered final self::Class* #this) → () →* dynamic
+  return () → dynamic => self::Extension|testInternal(#this);
+static method GenericExtension|set#setter<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|set#setter::T*>* #this, self::GenericExtension|set#setter::T* value) → void {}
+static method main() → dynamic {
+  self::Class* c = new self::Class::•();
+  self::expect(null, c.{self::Class::field}{core::int*});
+  self::Extension|set#simpleSetter(c, 0);
+  self::expect(0, c.{self::Class::field}{core::int*});
+  self::expect(1, let final core::int* #t13 = 1 in let final void #t14 = self::Extension|set#simpleSetter(c, #t13) in #t13);
+  self::Extension|set#simpleSetter(c, 2);
+  self::expect(2, c.{self::Class::field}{core::int*});
+  self::expect(3, let final self::Class* #t15 = c in let final core::int* #t16 = 3 in let final void #t17 = self::Extension|set#simpleSetter(#t15, #t16) in #t16);
+  self::Extension|set#mutatingSetter(c, 0);
+  self::expect(1, c.{self::Class::field}{core::int*});
+  self::expect(2, let final core::int* #t18 = 2 in let final void #t19 = self::Extension|set#mutatingSetter(c, #t18) in #t18);
+  self::expect(3, c.{self::Class::field}{core::int*});
+  self::Extension|set#mutatingSetter(c, 4);
+  self::expect(5, c.{self::Class::field}{core::int*});
+  self::expect(6, let final self::Class* #t20 = c in let final core::int* #t21 = 6 in let final void #t22 = self::Extension|set#mutatingSetter(#t20, #t21) in #t21);
+  self::expect(7, c.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithReturn(c, 1);
+  self::expect(1, c.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithReturn(c, 2.{core::int::unary-}(){() →* core::int*});
+  self::expect(2, c.{self::Class::field}{core::int*});
+  self::expect(3, let final core::int* #t23 = 3 in let final void #t24 = self::Extension|set#setterWithReturn(c, #t23) in #t23);
+  self::expect(3, c.{self::Class::field}{core::int*});
+  self::expect(4.{core::int::unary-}(){() →* core::int*}, let final core::int* #t25 = 4.{core::int::unary-}(){() →* core::int*} in let final void #t26 = self::Extension|set#setterWithReturn(c, #t25) in #t25);
+  self::expect(4, c.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithReturn(c, 5);
+  self::expect(5, c.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithReturn(c, 6.{core::int::unary-}(){() →* core::int*});
+  self::expect(6, c.{self::Class::field}{core::int*});
+  self::expect(7, let final self::Class* #t27 = c in let final core::int* #t28 = 7 in let final void #t29 = self::Extension|set#setterWithReturn(#t27, #t28) in #t28);
+  self::expect(7, c.{self::Class::field}{core::int*});
+  self::expect(8.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t30 = c in let final core::int* #t31 = 8.{core::int::unary-}(){() →* core::int*} in let final void #t32 = self::Extension|set#setterWithReturn(#t30, #t31) in #t31);
+  self::expect(8, c.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithClosure(c, 1);
+  self::expect(1, c.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithClosure(c, 2.{core::int::unary-}(){() →* core::int*});
+  self::expect(2, c.{self::Class::field}{core::int*});
+  self::expect(3, let final core::int* #t33 = 3 in let final void #t34 = self::Extension|set#setterWithClosure(c, #t33) in #t33);
+  self::expect(3, c.{self::Class::field}{core::int*});
+  self::expect(4.{core::int::unary-}(){() →* core::int*}, let final core::int* #t35 = 4.{core::int::unary-}(){() →* core::int*} in let final void #t36 = self::Extension|set#setterWithClosure(c, #t35) in #t35);
+  self::expect(4, c.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithClosure(c, 5);
+  self::expect(5, c.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithClosure(c, 6.{core::int::unary-}(){() →* core::int*});
+  self::expect(6, c.{self::Class::field}{core::int*});
+  self::expect(7, let final self::Class* #t37 = c in let final core::int* #t38 = 7 in let final void #t39 = self::Extension|set#setterWithClosure(#t37, #t38) in #t38);
+  self::expect(7, c.{self::Class::field}{core::int*});
+  self::expect(8.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t40 = c in let final core::int* #t41 = 8.{core::int::unary-}(){() →* core::int*} in let final void #t42 = self::Extension|set#setterWithClosure(#t40, #t41) in #t41);
+  self::expect(8, c.{self::Class::field}{core::int*});
+  self::Extension|set#simpleSetter(c, 0);
+  self::expect(0, let final self::Class* #t43 = c in #t43 == null ?{core::int*} null : #t43.{self::Class::field}{core::int*});
+  self::expect(1, let final self::Class* #t44 = c in #t44 == null ?{core::int*} null : let final core::int* #t45 = 1 in let final void #t46 = self::Extension|set#simpleSetter(#t44, #t45) in #t45);
+  self::Extension|set#simpleSetter(c, 2);
+  self::expect(2, let final self::Class* #t47 = c in #t47 == null ?{core::int*} null : #t47.{self::Class::field}{core::int*});
+  self::expect(3, let final self::Class* #t48 = c in let final core::int* #t49 = 3 in let final void #t50 = self::Extension|set#simpleSetter(#t48, #t49) in #t49);
+  self::Extension|set#mutatingSetter(c, 0);
+  self::expect(1, let final self::Class* #t51 = c in #t51 == null ?{core::int*} null : #t51.{self::Class::field}{core::int*});
+  self::expect(2, let final self::Class* #t52 = c in #t52 == null ?{core::int*} null : let final core::int* #t53 = 2 in let final void #t54 = self::Extension|set#mutatingSetter(#t52, #t53) in #t53);
+  self::expect(3, let final self::Class* #t55 = c in #t55 == null ?{core::int*} null : #t55.{self::Class::field}{core::int*});
+  self::Extension|set#mutatingSetter(c, 4);
+  self::expect(5, let final self::Class* #t56 = c in #t56 == null ?{core::int*} null : #t56.{self::Class::field}{core::int*});
+  self::expect(6, let final self::Class* #t57 = c in let final core::int* #t58 = 6 in let final void #t59 = self::Extension|set#mutatingSetter(#t57, #t58) in #t58);
+  self::expect(7, let final self::Class* #t60 = c in #t60 == null ?{core::int*} null : #t60.{self::Class::field}{core::int*});
+  let final self::Class* #t61 = c in #t61 == null ?{core::int*} null : self::Extension|set#setterWithReturn(#t61, 1);
+  self::expect(1, let final self::Class* #t62 = c in #t62 == null ?{core::int*} null : #t62.{self::Class::field}{core::int*});
+  let final self::Class* #t63 = c in #t63 == null ?{core::int*} null : self::Extension|set#setterWithReturn(#t63, 2.{core::int::unary-}(){() →* core::int*});
+  self::expect(2, let final self::Class* #t64 = c in #t64 == null ?{core::int*} null : #t64.{self::Class::field}{core::int*});
+  self::expect(3, let final self::Class* #t65 = c in #t65 == null ?{core::int*} null : let final core::int* #t66 = 3 in let final void #t67 = self::Extension|set#setterWithReturn(#t65, #t66) in #t66);
+  self::expect(3, let final self::Class* #t68 = c in #t68 == null ?{core::int*} null : #t68.{self::Class::field}{core::int*});
+  self::expect(4.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t69 = c in #t69 == null ?{core::int*} null : let final core::int* #t70 = 4.{core::int::unary-}(){() →* core::int*} in let final void #t71 = self::Extension|set#setterWithReturn(#t69, #t70) in #t70);
+  self::expect(4, let final self::Class* #t72 = c in #t72 == null ?{core::int*} null : #t72.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithReturn(c, 5);
+  self::expect(5, let final self::Class* #t73 = c in #t73 == null ?{core::int*} null : #t73.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithReturn(c, 6.{core::int::unary-}(){() →* core::int*});
+  self::expect(6, let final self::Class* #t74 = c in #t74 == null ?{core::int*} null : #t74.{self::Class::field}{core::int*});
+  self::expect(7, let final self::Class* #t75 = c in let final core::int* #t76 = 7 in let final void #t77 = self::Extension|set#setterWithReturn(#t75, #t76) in #t76);
+  self::expect(7, let final self::Class* #t78 = c in #t78 == null ?{core::int*} null : #t78.{self::Class::field}{core::int*});
+  self::expect(8.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t79 = c in let final core::int* #t80 = 8.{core::int::unary-}(){() →* core::int*} in let final void #t81 = self::Extension|set#setterWithReturn(#t79, #t80) in #t80);
+  self::expect(8, let final self::Class* #t82 = c in #t82 == null ?{core::int*} null : #t82.{self::Class::field}{core::int*});
+  let final self::Class* #t83 = c in #t83 == null ?{core::int*} null : self::Extension|set#setterWithClosure(#t83, 1);
+  self::expect(1, let final self::Class* #t84 = c in #t84 == null ?{core::int*} null : #t84.{self::Class::field}{core::int*});
+  let final self::Class* #t85 = c in #t85 == null ?{core::int*} null : self::Extension|set#setterWithClosure(#t85, 2.{core::int::unary-}(){() →* core::int*});
+  self::expect(2, let final self::Class* #t86 = c in #t86 == null ?{core::int*} null : #t86.{self::Class::field}{core::int*});
+  self::expect(3, let final self::Class* #t87 = c in #t87 == null ?{core::int*} null : let final core::int* #t88 = 3 in let final void #t89 = self::Extension|set#setterWithClosure(#t87, #t88) in #t88);
+  self::expect(3, let final self::Class* #t90 = c in #t90 == null ?{core::int*} null : #t90.{self::Class::field}{core::int*});
+  self::expect(4.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t91 = c in #t91 == null ?{core::int*} null : let final core::int* #t92 = 4.{core::int::unary-}(){() →* core::int*} in let final void #t93 = self::Extension|set#setterWithClosure(#t91, #t92) in #t92);
+  self::expect(4, let final self::Class* #t94 = c in #t94 == null ?{core::int*} null : #t94.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithClosure(c, 5);
+  self::expect(5, let final self::Class* #t95 = c in #t95 == null ?{core::int*} null : #t95.{self::Class::field}{core::int*});
+  self::Extension|set#setterWithClosure(c, 6.{core::int::unary-}(){() →* core::int*});
+  self::expect(6, let final self::Class* #t96 = c in #t96 == null ?{core::int*} null : #t96.{self::Class::field}{core::int*});
+  self::expect(7, let final self::Class* #t97 = c in let final core::int* #t98 = 7 in let final void #t99 = self::Extension|set#setterWithClosure(#t97, #t98) in #t98);
+  self::expect(7, let final self::Class* #t100 = c in #t100 == null ?{core::int*} null : #t100.{self::Class::field}{core::int*});
+  self::expect(8.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t101 = c in let final core::int* #t102 = 8.{core::int::unary-}(){() →* core::int*} in let final void #t103 = self::Extension|set#setterWithClosure(#t101, #t102) in #t102);
+  self::expect(8, let final self::Class* #t104 = c in #t104 == null ?{core::int*} null : #t104.{self::Class::field}{core::int*});
+  c.{self::Class::field} = null;
+  let final self::Class* #t105 = c in self::Extension|get#simpleSetter(#t105) == null ?{core::int*} self::Extension|set#simpleSetter(#t105, 1) : null;
+  self::expect(1, c.{self::Class::field}{core::int*});
+  self::expect(1, let final self::Class* #t106 = c in let final core::int* #t107 = self::Extension|get#simpleSetter(#t106) in #t107 == null ?{core::int*} let final core::int* #t108 = 2 in let final void #t109 = self::Extension|set#simpleSetter(#t106, #t108) in #t108 : #t107);
+  c.{self::Class::field} = null;
+  self::expect(2, let final self::Class* #t110 = c in let final core::int* #t111 = self::Extension|get#simpleSetter(#t110) in #t111 == null ?{core::int*} let final core::int* #t112 = 2 in let final void #t113 = self::Extension|set#simpleSetter(#t110, #t112) in #t112 : #t111);
+  let final self::Class* #t114 = c in #t114 == null ?{Null} null : #t114.{self::Class::field} = null;
+  let final self::Class* #t115 = c in #t115 == null ?{core::int*} null : self::Extension|get#simpleSetter(#t115) == null ?{core::int*} self::Extension|set#simpleSetter(#t115, 1) : null;
+  self::expect(1, let final self::Class* #t116 = c in #t116 == null ?{core::int*} null : #t116.{self::Class::field}{core::int*});
+  self::expect(1, let final self::Class* #t117 = c in #t117 == null ?{core::int*} null : let final core::int* #t118 = self::Extension|get#simpleSetter(#t117) in #t118 == null ?{core::int*} let final core::int* #t119 = 2 in let final void #t120 = self::Extension|set#simpleSetter(#t117, #t119) in #t119 : #t118);
+  let final self::Class* #t121 = c in #t121 == null ?{Null} null : #t121.{self::Class::field} = null;
+  self::expect(2, let final self::Class* #t122 = c in #t122 == null ?{core::int*} null : let final core::int* #t123 = self::Extension|get#simpleSetter(#t122) in #t123 == null ?{core::int*} let final core::int* #t124 = 2 in let final void #t125 = self::Extension|set#simpleSetter(#t122, #t124) in #t124 : #t123);
+  self::Extension|testInternal(new self::Class::•());
+  self::GenericClass<core::int*>* genericClass = new self::GenericClass::•<core::int*>();
+  self::expect(1, let final self::GenericClass<core::int*>* #t126 = genericClass in let final core::int* #t127 = 1 in let final void #t128 = self::GenericExtension|set#setter<core::int*>(#t126, #t127) in #t127);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/extension_setter_error.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/extension_setter_error.dart.weak.modular.expect
new file mode 100644
index 0000000..9811ed6
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/extension_setter_error.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/extension_setter_error.dart:13:41: Error: A value of type 'GenericClass<int>' can't be assigned to a variable of type 'GenericClass<double>'.
+//  - 'GenericClass' is from 'pkg/front_end/testcases/extensions/extension_setter_error.dart'.
+//   expect(null, GenericExtension<double>(genericClass).setter = null);
+//                                         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class GenericClass<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::GenericClass<self::GenericClass::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension GenericExtension<T extends core::Object* = dynamic> on self::GenericClass<T*>* {
+  set setter = self::GenericExtension|set#setter;
+}
+static method GenericExtension|set#setter<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|set#setter::T*>* #this, self::GenericExtension|set#setter::T* value) → void {}
+static method error() → dynamic {
+  self::GenericClass<core::int*>* genericClass = new self::GenericClass::•<core::int*>();
+  self::expect(null, let final self::GenericClass<core::int*>* #t1 = invalid-expression "pkg/front_end/testcases/extensions/extension_setter_error.dart:13:41: Error: A value of type 'GenericClass<int>' can't be assigned to a variable of type 'GenericClass<double>'.
+ - 'GenericClass' is from 'pkg/front_end/testcases/extensions/extension_setter_error.dart'.
+  expect(null, GenericExtension<double>(genericClass).setter = null);
+                                        ^" in genericClass as{TypeError} self::GenericClass<core::double*>* in let final Null #t2 = null in let final void #t3 = self::GenericExtension|set#setter<core::double*>(#t1, #t2) in #t2);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/external.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/external.dart.weak.modular.expect
new file mode 100644
index 0000000..f9c3590
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/external.dart.weak.modular.expect
@@ -0,0 +1,84 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+extension Extension<T extends core::num> on core::List<T> {
+  get field = self::Extension|get#field;
+  set field = self::Extension|set#field;
+  static get staticField = get self::Extension|staticField;
+  static set staticField = set self::Extension|staticField;
+  get finalField = self::Extension|get#finalField;
+  static get staticFinalField = get self::Extension|staticFinalField;
+  method method = self::Extension|method;
+  tearoff method = self::Extension|get#method;
+  static method staticMethod = self::Extension|staticMethod;
+  get getter = self::Extension|get#getter;
+  static get staticGetter = get self::Extension|staticGetter;
+  get property = self::Extension|get#property;
+  static get staticProperty = get self::Extension|staticProperty;
+  get fieldSetter = self::Extension|get#fieldSetter;
+  static get staticFieldSetter = get self::Extension|staticFieldSetter;
+  set setter = self::Extension|set#setter;
+  static set staticSetter = set self::Extension|staticSetter;
+  set property = self::Extension|set#property;
+  static set staticProperty = set self::Extension|staticProperty;
+  set fieldSetter = self::Extension|set#fieldSetter;
+  static set staticFieldSetter = set self::Extension|staticFieldSetter;
+}
+external static method Extension|get#field<T extends core::num>(core::List<self::Extension|get#field::T> #this) → self::Extension|get#field::T;
+external static method Extension|set#field<T extends core::num>(core::List<self::Extension|set#field::T> #this, self::Extension|set#field::T #externalFieldValue) → void;
+external static get Extension|staticField() → core::int;
+external static set Extension|staticField(core::int #externalFieldValue) → void;
+external static method Extension|get#finalField<T extends core::num>(core::List<self::Extension|get#finalField::T> #this) → self::Extension|get#finalField::T;
+external static get Extension|staticFinalField() → core::int;
+external static method Extension|method<T extends core::num>(lowered final core::List<self::Extension|method::T> #this) → self::Extension|method::T;
+static method Extension|get#method<T extends core::num>(lowered final core::List<self::Extension|get#method::T> #this) → () → self::Extension|get#method::T
+  return () → self::Extension|get#method::T => self::Extension|method<self::Extension|get#method::T>(#this);
+external static method Extension|staticMethod() → core::int;
+external static method Extension|get#getter<T extends core::num>(lowered final core::List<self::Extension|get#getter::T> #this) → self::Extension|get#getter::T;
+external static get Extension|staticGetter() → core::int;
+external static method Extension|set#setter<T extends core::num>(lowered final core::List<self::Extension|set#setter::T> #this, self::Extension|set#setter::T value) → void;
+external static set Extension|staticSetter(core::int value) → void;
+external static method Extension|get#property<T extends core::num>(lowered final core::List<self::Extension|get#property::T> #this) → self::Extension|get#property::T;
+external static method Extension|set#property<T extends core::num>(lowered final core::List<self::Extension|set#property::T> #this, self::Extension|set#property::T value) → void;
+external static get Extension|staticProperty() → core::int;
+external static set Extension|staticProperty(core::int value) → void;
+external static method Extension|get#fieldSetter<T extends core::num>(core::List<self::Extension|get#fieldSetter::T> #this) → self::Extension|get#fieldSetter::T;
+external static method Extension|set#fieldSetter<T extends core::num>(lowered final core::List<self::Extension|set#fieldSetter::T> #this, self::Extension|set#fieldSetter::T value) → void;
+external static get Extension|staticFieldSetter() → core::int;
+external static set Extension|staticFieldSetter(core::int value) → void;
+static method test() → dynamic {
+  core::List<core::int> list = <core::int>[];
+  core::int value = self::Extension|get#field<core::int>(list);
+  self::Extension|set#field<core::int>(list, value);
+  value = self::Extension|get#finalField<core::int>(list);
+  value = self::Extension|method<core::int>(list);
+  value = self::Extension|get#getter<core::int>(list);
+  self::Extension|set#setter<core::int>(list, value);
+  value = self::Extension|get#property<core::int>(list);
+  self::Extension|set#property<core::int>(list, value);
+  value = self::Extension|get#fieldSetter<core::int>(list);
+  self::Extension|set#fieldSetter<core::int>(list, value);
+  core::List<core::int> iterable = list;
+  core::num n = self::Extension|get#field<core::num>(iterable);
+  self::Extension|set#field<core::num>(iterable, n);
+  n = self::Extension|get#finalField<core::num>(iterable);
+  n = self::Extension|method<core::num>(iterable);
+  n = self::Extension|get#getter<core::num>(iterable);
+  self::Extension|set#setter<core::num>(iterable, n);
+  n = self::Extension|get#property<core::num>(iterable);
+  self::Extension|set#property<core::num>(iterable, n);
+  n = self::Extension|get#fieldSetter<core::num>(iterable);
+  self::Extension|set#fieldSetter<core::num>(iterable, n);
+  value = self::Extension|staticField;
+  self::Extension|staticField = value;
+  value = self::Extension|staticFinalField;
+  value = self::Extension|staticMethod();
+  value = self::Extension|staticGetter;
+  self::Extension|staticSetter = value;
+  value = self::Extension|staticProperty;
+  self::Extension|staticProperty = value;
+  value = self::Extension|staticFieldSetter;
+  self::Extension|staticFieldSetter = value;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/generic_function_in_generic_extension.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/generic_function_in_generic_extension.dart.weak.modular.expect
new file mode 100644
index 0000000..47243334
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/generic_function_in_generic_extension.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension<T extends core::Object* = dynamic> on self::Class<T*>* {
+  method method = self::Extension|method;
+  tearoff method = self::Extension|get#method;
+}
+static method Extension|method<T extends core::Object* = dynamic, R extends core::Object* = dynamic>(lowered final self::Class<self::Extension|method::T*>* #this, self::Extension|method::T* t) → self::Extension|method::R*
+  return null;
+static method Extension|get#method<T extends core::Object* = dynamic>(lowered final self::Class<self::Extension|get#method::T*>* #this) → <R extends core::Object* = dynamic>(self::Extension|get#method::T*) →* R*
+  return <R extends core::Object* = dynamic>(self::Extension|get#method::T* t) → R* => self::Extension|method<self::Extension|get#method::T*, R*>(#this, t);
+static method main() → dynamic {
+  let final dynamic #t1 = self::Extension|method<core::int*, dynamic>(new self::Class::•<core::int*>(), 0) in #t1 == null ?{core::String*} null : #t1.{core::Object::toString}(){() →* core::String*};
+}
diff --git a/pkg/front_end/testcases/extensions/getter_setter_conflict.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/getter_setter_conflict.dart.weak.modular.expect
new file mode 100644
index 0000000..6666d8f
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/getter_setter_conflict.dart.weak.modular.expect
@@ -0,0 +1,147 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:30:15: Error: The getter 'm2' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'm2'.
+//   expect(0, c.m2);
+//               ^^
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:31:5: Error: The setter 'm1' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'm1'.
+//   c.m1 = 2;
+//     ^^
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:32:5: Error: The property 'm3' is defined in multiple extensions for 'Class' and neither is more specific.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   c.m3;
+//     ^^
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:13:12: Context: This is one of the extension members.
+//   void set m3(int x) {}
+//            ^^
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:18:11: Context: This is one of the extension members.
+//   int get m3 => 0;
+//           ^^
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:33:5: Error: The property 'm3' is defined in multiple extensions for 'Class' and neither is more specific.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   c.m3 = 2;
+//     ^^
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:13:12: Context: This is one of the extension members.
+//   void set m3(int x) {}
+//            ^^
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:18:11: Context: This is one of the extension members.
+//   int get m3 => 0;
+//           ^^
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:34:5: Error: The property 'm4' is defined in multiple extensions for 'Class' and neither is more specific.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   c.m4;
+//     ^^
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:14:11: Context: This is one of the extension members.
+//   int get m4 => 0;
+//           ^^
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:19:12: Context: This is one of the extension members.
+//   void set m4(int x) {}
+//            ^^
+//
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:35:5: Error: The property 'm4' is defined in multiple extensions for 'Class' and neither is more specific.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+// Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+//   c.m4 = 2;
+//     ^^
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:14:11: Context: This is one of the extension members.
+//   int get m4 => 0;
+//           ^^
+// pkg/front_end/testcases/extensions/getter_setter_conflict.dart:19:12: Context: This is one of the extension members.
+//   void set m4(int x) {}
+//            ^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  get m1() → core::int*
+    return 0;
+  set m2(core::int* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension0 on self::Class* {
+  get m2 = self::Extension0|get#m2;
+  get m4 = self::Extension0|get#m4;
+  set m1 = self::Extension0|set#m1;
+  set m3 = self::Extension0|set#m3;
+}
+extension Extension1 on self::Class* {
+  get m3 = self::Extension1|get#m3;
+  set m4 = self::Extension1|set#m4;
+}
+static method Extension0|set#m1(lowered final self::Class* #this, core::int* x) → void {}
+static method Extension0|get#m2(lowered final self::Class* #this) → core::int*
+  return 0;
+static method Extension0|set#m3(lowered final self::Class* #this, core::int* x) → void {}
+static method Extension0|get#m4(lowered final self::Class* #this) → core::int*
+  return 0;
+static method Extension1|get#m3(lowered final self::Class* #this) → core::int*
+  return 0;
+static method Extension1|set#m4(lowered final self::Class* #this, core::int* x) → void {}
+static method main() → dynamic {
+  self::Class* c = new self::Class::•();
+  self::expect(0, c.{self::Class::m1}{core::int*});
+  c.{self::Class::m2} = 2;
+}
+static method errors() → dynamic {
+  self::Class* c = new self::Class::•();
+  self::expect(0, invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:30:15: Error: The getter 'm2' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'm2'.
+  expect(0, c.m2);
+              ^^" in c{<unresolved>}.m2);
+  invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:31:5: Error: The setter 'm1' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'm1'.
+  c.m1 = 2;
+    ^^" in c{<unresolved>}.m1 = 2;
+  invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:32:5: Error: The property 'm3' is defined in multiple extensions for 'Class' and neither is more specific.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  c.m3;
+    ^^" in c{<unresolved>}.m3;
+  invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:33:5: Error: The property 'm3' is defined in multiple extensions for 'Class' and neither is more specific.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  c.m3 = 2;
+    ^^" in c{<unresolved>}.m3 = 2;
+  invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:34:5: Error: The property 'm4' is defined in multiple extensions for 'Class' and neither is more specific.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  c.m4;
+    ^^" in c{<unresolved>}.m4;
+  invalid-expression "pkg/front_end/testcases/extensions/getter_setter_conflict.dart:35:5: Error: The property 'm4' is defined in multiple extensions for 'Class' and neither is more specific.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/getter_setter_conflict.dart'.
+Try using an explicit extension application of the wanted extension or hiding unwanted extensions from scope.
+  c.m4 = 2;
+    ^^" in c{<unresolved>}.m4 = 2;
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/if_null.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/if_null.dart.weak.modular.expect
new file mode 100644
index 0000000..34aa9aa
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/if_null.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int* field = null;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+  get property = self::Extension|get#property;
+  method method = self::Extension|method;
+  tearoff method = self::Extension|get#method;
+  set property = self::Extension|set#property;
+}
+static method Extension|get#property(lowered final self::Class* #this) → core::int*
+  return #this.{self::Class::field}{core::int*};
+static method Extension|set#property(lowered final self::Class* #this, core::int* value) → void {
+  #this.{self::Class::field} = value;
+}
+static method Extension|method(lowered final self::Class* #this) → core::int*
+  return #this.{self::Class::field}{core::int*};
+static method Extension|get#method(lowered final self::Class* #this) → () →* core::int*
+  return () → core::int* => self::Extension|method(#this);
+static method main() → dynamic {
+  self::Class* c;
+  let final core::int* #t1 = let final self::Class* #t2 = c in #t2 == null ?{core::int*} null : self::Extension|get#property(#t2) in #t1 == null ?{core::int*} 0 : #t1;
+  let final core::int* #t3 = let final self::Class* #t4 = c in #t4 == null ?{core::int*} null : self::Extension|get#property(#t4) in #t3 == null ?{core::int*} 0 : #t3;
+  let final self::Class* #t5 = c in #t5 == null ?{core::int*} null : self::Extension|set#property(#t5, let final core::int* #t6 = 42 in #t6 == null ?{core::int*} 0 : #t6);
+  let final self::Class* #t7 = c in #t7 == null ?{core::int*} null : self::Extension|set#property(#t7, let final core::int* #t8 = 42 in #t8 == null ?{core::int*} 0 : #t8);
+  let final core::int* #t9 = let final self::Class* #t10 = c in #t10 == null ?{core::int*} null : let final core::int* #t11 = 42 in let final void #t12 = self::Extension|set#property(#t10, #t11) in #t11 in #t9 == null ?{core::int*} 0 : #t9;
+  let final core::int* #t13 = let final self::Class* #t14 = c in #t14 == null ?{core::int*} null : let final core::int* #t15 = 42 in let final void #t16 = self::Extension|set#property(#t14, #t15) in #t15 in #t13 == null ?{core::int*} 0 : #t13;
+  let final core::int* #t17 = let final self::Class* #t18 = c in #t18 == null ?{core::int*} null : self::Extension|method(#t18) in #t17 == null ?{core::int*} 0 : #t17;
+  let final core::int* #t19 = let final self::Class* #t20 = c in #t20 == null ?{core::int*} null : self::Extension|method(#t20) in #t19 == null ?{core::int*} 0 : #t19;
+  c = new self::Class::•();
+  let final core::int* #t21 = self::Extension|get#property(c) in #t21 == null ?{core::int*} 0 : #t21;
+  let final core::int* #t22 = self::Extension|get#property(c) in #t22 == null ?{core::int*} 0 : #t22;
+}
diff --git a/pkg/front_end/testcases/extensions/implicit_extension_inference.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/implicit_extension_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..68819f0
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/implicit_extension_inference.dart.weak.modular.expect
@@ -0,0 +1,86 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class GenericClass<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::GenericClass<self::GenericClass::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension GenericExtension<T extends core::Object* = dynamic> on self::GenericClass<T*>* {
+  get property = self::GenericExtension|get#property;
+  method method = self::GenericExtension|method;
+  tearoff method = self::GenericExtension|get#method;
+  method genericMethod1 = self::GenericExtension|genericMethod1;
+  tearoff genericMethod1 = self::GenericExtension|get#genericMethod1;
+}
+static method GenericExtension|get#property<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#property::T*>* #this) → self::GenericExtension|get#property::T*
+  return null;
+static method GenericExtension|method<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|method::T*>* #this, self::GenericExtension|method::T* t) → self::GenericExtension|method::T*
+  return null;
+static method GenericExtension|get#method<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#method::T*>* #this) → (self::GenericExtension|get#method::T*) →* self::GenericExtension|get#method::T*
+  return (self::GenericExtension|get#method::T* t) → self::GenericExtension|get#method::T* => self::GenericExtension|method<self::GenericExtension|get#method::T*>(#this, t);
+static method GenericExtension|genericMethod1<T extends core::Object* = dynamic, S extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|genericMethod1::T*>* #this, self::GenericExtension|genericMethod1::S* s) → self::GenericExtension|genericMethod1::S*
+  return null;
+static method GenericExtension|get#genericMethod1<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#genericMethod1::T*>* #this) → <S extends core::Object* = dynamic>(S*) →* S*
+  return <S extends core::Object* = dynamic>(S* s) → S* => self::GenericExtension|genericMethod1<self::GenericExtension|get#genericMethod1::T*, S*>(#this, s);
+static method main() → dynamic {
+  self::A* aVariable;
+  self::C* cVariable;
+  self::GenericClass<self::A*>* aClass;
+  self::GenericClass<self::B*>* bClass;
+  self::GenericClass<self::C*>* cClass;
+  cVariable = self::GenericExtension|get#property<self::A*>(aClass) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|get#property<self::B*>(bClass) as{TypeError} self::C*;
+  aVariable = self::GenericExtension|get#property<self::C*>(cClass);
+  cVariable = self::GenericExtension|method<self::A*>(aClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|method<self::B*>(bClass, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  aVariable = self::GenericExtension|method<self::C*>(cClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::C*>(aClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::A*>(aClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::B*>(aClass, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::A*, self::C*>(aClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::C*>(bClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::A*>(bClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::B*>(bClass, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::B*, self::C*>(bClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::C*>(cClass, aVariable as{TypeError} self::C*);
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::A*>(cClass, aVariable) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::B*>(cClass, aVariable as{TypeError} self::B*) as{TypeError} self::C*;
+  cVariable = self::GenericExtension|genericMethod1<self::C*, self::C*>(cClass, aVariable as{TypeError} self::C*);
+}
diff --git a/pkg/front_end/testcases/extensions/implicit_this.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/implicit_this.dart.weak.modular.expect
new file mode 100644
index 0000000..9328ef6
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/implicit_this.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  field core::Object* field = null;
+  synthetic constructor •() → self::A1*
+    : super core::Object::•()
+    ;
+  method method1() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension A2 on self::A1* {
+  method method2 = self::A2|method2;
+  tearoff method2 = self::A2|get#method2;
+  method method3 = self::A2|method3;
+  tearoff method3 = self::A2|get#method3;
+  method method4 = self::A2|method4;
+  tearoff method4 = self::A2|get#method4;
+}
+static method A2|method2(lowered final self::A1* #this) → void
+  return #this.{self::A1::method1}(){() →* void};
+static method A2|get#method2(lowered final self::A1* #this) → () →* void
+  return () → void => self::A2|method2(#this);
+static method A2|method3(lowered final self::A1* #this) → core::Object*
+  return #this.{self::A1::field}{core::Object*};
+static method A2|get#method3(lowered final self::A1* #this) → () →* core::Object*
+  return () → core::Object* => self::A2|method3(#this);
+static method A2|method4(lowered final self::A1* #this, core::Object* o) → void {
+  #this.{self::A1::field} = o;
+}
+static method A2|get#method4(lowered final self::A1* #this) → (core::Object*) →* void
+  return (core::Object* o) → void => self::A2|method4(#this, o);
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/import_from_dill/main.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/import_from_dill/main.dart.weak.modular.expect
new file mode 100644
index 0000000..216ab75
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/import_from_dill/main.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library;
+import self as self;
+import "main_lib1.dart" as mai;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///main_lib1.dart";
+
+static method main() → dynamic {
+  mai::Extension|set#instanceProperty(0, mai::Extension|get#instanceProperty(1));
+  mai::Extension|instanceMethod(2);
+  mai::Extension|get#instanceMethod(3);
+  mai::Extension|staticField = #C1;
+  mai::Extension|set#instanceProperty(3, mai::Extension|staticFinalField);
+  mai::Extension|staticProperty = mai::Extension|staticProperty;
+  mai::Extension|staticMethod();
+  #C2;
+}
+
+constants  {
+  #C1 = 42
+  #C2 = static-tearoff mai::Extension|staticMethod
+}
diff --git a/pkg/front_end/testcases/extensions/import_via_prefix.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/import_via_prefix.dart.weak.modular.expect
new file mode 100644
index 0000000..0b2f376
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/import_via_prefix.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+import self as self;
+import "import_via_prefix_lib.dart" as imp;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///import_via_prefix_lib.dart" as prefix;
+
+static method main() → dynamic {
+  self::expect(3, imp::Extension|method("foo"));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+library;
+import self as imp;
+import "dart:core" as core;
+
+extension Extension on core::String* {
+  method method = imp::Extension|method;
+  tearoff method = imp::Extension|get#method;
+}
+static method Extension|method(lowered final core::String* #this) → core::int*
+  return #this.{core::String::length}{core::int*};
+static method Extension|get#method(lowered final core::String* #this) → () →* core::int*
+  return () → core::int* => imp::Extension|method(#this);
diff --git a/pkg/front_end/testcases/extensions/index.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/index.dart.weak.modular.expect
new file mode 100644
index 0000000..e91fc4b
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/index.dart.weak.modular.expect
@@ -0,0 +1,123 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class MapLike<K extends core::Object* = dynamic, V extends core::Object* = dynamic> extends core::Object {
+  final field core::Map<self::MapLike::K*, self::MapLike::V*>* _map = <self::MapLike::K*, self::MapLike::V*>{};
+  synthetic constructor •() → self::MapLike<self::MapLike::K*, self::MapLike::V*>*
+    : super core::Object::•()
+    ;
+  method get(core::Object* key) → self::MapLike::V*
+    return this.{self::MapLike::_map}{core::Map<self::MapLike::K*, self::MapLike::V*>*}.{core::Map::[]}(key){(core::Object*) →* self::MapLike::V*};
+  method put(covariant-by-class self::MapLike::K* key, covariant-by-class self::MapLike::V* value) → self::MapLike::V*
+    return let final core::Map<self::MapLike::K*, self::MapLike::V*>* #t1 = this.{self::MapLike::_map}{core::Map<self::MapLike::K*, self::MapLike::V*>*} in let final self::MapLike::K* #t2 = key in let final self::MapLike::V* #t3 = value in let final void #t4 = #t1.{core::Map::[]=}(#t2, #t3){(self::MapLike::K*, self::MapLike::V*) →* void} in #t3;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension<K extends core::Object* = dynamic, V extends core::Object* = dynamic> on self::MapLike<K*, V*>* {
+  operator [] = self::Extension|[];
+  operator []= = self::Extension|[]=;
+}
+static method Extension|[]<K extends core::Object* = dynamic, V extends core::Object* = dynamic>(lowered final self::MapLike<self::Extension|[]::K*, self::Extension|[]::V*>* #this, core::Object* key) → self::Extension|[]::V*
+  return #this.{self::MapLike::get}(key){(core::Object*) →* self::Extension|[]::V*};
+static method Extension|[]=<K extends core::Object* = dynamic, V extends core::Object* = dynamic>(lowered final self::MapLike<self::Extension|[]=::K*, self::Extension|[]=::V*>* #this, self::Extension|[]=::K* key, self::Extension|[]=::V* value) → void
+  return #this.{self::MapLike::put}(key, value){(self::Extension|[]=::K*, self::Extension|[]=::V*) →* self::Extension|[]=::V*};
+static method main() → dynamic {
+  self::implicit();
+  self::explicitWithTypeArguments();
+  self::explicitInferredTypeArguments();
+}
+static method implicit() → dynamic {
+  self::MapLike<core::int*, core::String*>* map1 = new self::MapLike::•<core::int*, core::String*>();
+  self::expect(null, self::Extension|[]<core::int*, core::String*>(map1, 0));
+  map1.{self::MapLike::put}(0, "0"){(core::int*, core::String*) →* core::String*};
+  self::expect("0", self::Extension|[]<core::int*, core::String*>(map1, 0));
+  self::expect(null, self::Extension|[]<core::int*, core::String*>(map1, 1));
+  self::Extension|[]=<core::int*, core::String*>(map1, 1, "1");
+  self::expect("1", self::Extension|[]<core::int*, core::String*>(map1, 1));
+  self::expect("2", let final self::MapLike<core::int*, core::String*>* #t5 = map1 in let final core::int* #t6 = 1 in let final core::String* #t7 = "2" in let final void #t8 = self::Extension|[]=<core::int*, core::String*>(#t5, #t6, #t7) in #t7);
+  self::expect("2", self::Extension|[]<core::int*, core::String*>(map1, 1));
+  let final self::MapLike<core::int*, core::String*>* #t9 = map1 in let final core::int* #t10 = 1 in self::Extension|[]<core::int*, core::String*>(#t9, #t10) == null ?{core::String*} self::Extension|[]=<core::int*, core::String*>(#t9, #t10, "3") : null;
+  self::expect("2", self::Extension|[]<core::int*, core::String*>(map1, 1));
+  self::expect("2", let final self::MapLike<core::int*, core::String*>* #t11 = map1 in let final core::int* #t12 = 1 in let final core::String* #t13 = self::Extension|[]<core::int*, core::String*>(#t11, #t12) in #t13 == null ?{core::String*} let final core::String* #t14 = "4" in let final void #t15 = self::Extension|[]=<core::int*, core::String*>(#t11, #t12, #t14) in #t14 : #t13);
+  self::expect("2", self::Extension|[]<core::int*, core::String*>(map1, 1));
+  let final self::MapLike<core::int*, core::String*>* #t16 = map1 in let final core::int* #t17 = 2 in self::Extension|[]<core::int*, core::String*>(#t16, #t17) == null ?{core::String*} self::Extension|[]=<core::int*, core::String*>(#t16, #t17, "2") : null;
+  self::expect("2", self::Extension|[]<core::int*, core::String*>(map1, 2));
+  self::expect("3", let final self::MapLike<core::int*, core::String*>* #t18 = map1 in let final core::int* #t19 = 3 in let final core::String* #t20 = self::Extension|[]<core::int*, core::String*>(#t18, #t19) in #t20 == null ?{core::String*} let final core::String* #t21 = "3" in let final void #t22 = self::Extension|[]=<core::int*, core::String*>(#t18, #t19, #t21) in #t21 : #t20);
+  self::expect("3", self::Extension|[]<core::int*, core::String*>(map1, 3));
+  self::MapLike<core::int*, core::int*>* map2 = new self::MapLike::•<core::int*, core::int*>();
+  self::expect(1, let final self::MapLike<core::int*, core::int*>* #t23 = map2 in let final core::int* #t24 = 0 in let final core::int* #t25 = 1 in let final void #t26 = self::Extension|[]=<core::int*, core::int*>(#t23, #t24, #t25) in #t25);
+  self::expect(3, let final self::MapLike<core::int*, core::int*>* #t27 = map2 in let final core::int* #t28 = 0 in let final core::int* #t29 = self::Extension|[]<core::int*, core::int*>(#t27, #t28).{core::num::+}(2){(core::num*) →* core::int*} in let final void #t30 = self::Extension|[]=<core::int*, core::int*>(#t27, #t28, #t29) in #t29);
+  self::expect(5, let final self::MapLike<core::int*, core::int*>* #t31 = map2 in let final core::int* #t32 = 0 in let final core::int* #t33 = self::Extension|[]<core::int*, core::int*>(#t31, #t32).{core::num::+}(2){(core::num*) →* core::int*} in let final void #t34 = self::Extension|[]=<core::int*, core::int*>(#t31, #t32, #t33) in #t33);
+  self::expect(5, let final self::MapLike<core::int*, core::int*>* #t35 = map2 in let final core::int* #t36 = 0 in let final core::int* #t37 = self::Extension|[]<core::int*, core::int*>(#t35, #t36) in let final void #t38 = self::Extension|[]=<core::int*, core::int*>(#t35, #t36, #t37.{core::num::+}(1){(core::num*) →* core::int*}) in #t37);
+  self::expect(6, self::Extension|[]<core::int*, core::int*>(map2, 0));
+  self::expect(5, let final self::MapLike<core::int*, core::int*>* #t39 = map2 in let final core::int* #t40 = 0 in let final core::int* #t41 = self::Extension|[]<core::int*, core::int*>(#t39, #t40).{core::num::-}(1){(core::num*) →* core::int*} in let final void #t42 = self::Extension|[]=<core::int*, core::int*>(#t39, #t40, #t41) in #t41);
+  self::expect(5, self::Extension|[]<core::int*, core::int*>(map2, 0));
+}
+static method explicitWithTypeArguments() → dynamic {
+  self::MapLike<core::int*, core::String*>* map1 = new self::MapLike::•<core::int*, core::String*>();
+  self::expect(null, self::Extension|[]<core::int*, core::String*>(map1, 0));
+  map1.{self::MapLike::put}(0, "0"){(core::int*, core::String*) →* core::String*};
+  self::expect("0", self::Extension|[]<core::int*, core::String*>(map1, 0));
+  self::expect(null, self::Extension|[]<core::int*, core::String*>(map1, 1));
+  self::Extension|[]=<core::int*, core::String*>(map1, 1, "1");
+  self::expect("1", self::Extension|[]<core::int*, core::String*>(map1, 1));
+  self::expect("2", let final self::MapLike<core::int*, core::String*>* #t43 = map1 in let final core::String* #t44 = "2" in let final void #t45 = self::Extension|[]=<core::int*, core::String*>(#t43, 1, #t44) in #t44);
+  self::expect("2", self::Extension|[]<core::int*, core::String*>(map1, 1));
+  let final self::MapLike<core::int*, core::String*>* #t46 = map1 in let final core::int* #t47 = 1 in self::Extension|[]<core::int*, core::String*>(#t46, #t47) == null ?{core::String*} self::Extension|[]=<core::int*, core::String*>(#t46, #t47, "3") : null;
+  self::expect("2", self::Extension|[]<core::int*, core::String*>(map1, 1));
+  self::expect("2", let final self::MapLike<core::int*, core::String*>* #t48 = map1 in let final core::int* #t49 = 1 in let final core::String* #t50 = self::Extension|[]<core::int*, core::String*>(#t48, #t49) in #t50 == null ?{core::String*} let final core::String* #t51 = "4" in let final void #t52 = self::Extension|[]=<core::int*, core::String*>(#t48, #t49, #t51) in #t51 : #t50);
+  self::expect("2", self::Extension|[]<core::int*, core::String*>(map1, 1));
+  let final self::MapLike<core::int*, core::String*>* #t53 = map1 in let final core::int* #t54 = 2 in self::Extension|[]<core::int*, core::String*>(#t53, #t54) == null ?{core::String*} self::Extension|[]=<core::int*, core::String*>(#t53, #t54, "2") : null;
+  self::expect("2", self::Extension|[]<core::int*, core::String*>(map1, 2));
+  self::expect("3", let final self::MapLike<core::int*, core::String*>* #t55 = map1 in let final core::int* #t56 = 3 in let final core::String* #t57 = self::Extension|[]<core::int*, core::String*>(#t55, #t56) in #t57 == null ?{core::String*} let final core::String* #t58 = "3" in let final void #t59 = self::Extension|[]=<core::int*, core::String*>(#t55, #t56, #t58) in #t58 : #t57);
+  self::expect("3", self::Extension|[]<core::int*, core::String*>(map1, 3));
+  self::MapLike<core::int*, core::int*>* map2 = new self::MapLike::•<core::int*, core::int*>();
+  self::expect(1, let final self::MapLike<core::int*, core::int*>* #t60 = map2 in let final core::int* #t61 = 1 in let final void #t62 = self::Extension|[]=<core::int*, core::int*>(#t60, 0, #t61) in #t61);
+  self::expect(3, let final self::MapLike<core::int*, core::int*>* #t63 = map2 in let final core::int* #t64 = 0 in let final core::int* #t65 = self::Extension|[]<core::int*, core::int*>(#t63, #t64).{core::num::+}(2){(core::num*) →* core::int*} in let final void #t66 = self::Extension|[]=<core::int*, core::int*>(#t63, #t64, #t65) in #t65);
+  self::expect(5, let final self::MapLike<core::int*, core::int*>* #t67 = map2 in let final core::int* #t68 = 0 in let final core::int* #t69 = self::Extension|[]<core::int*, core::int*>(#t67, #t68).{core::num::+}(2){(core::num*) →* core::int*} in let final void #t70 = self::Extension|[]=<core::int*, core::int*>(#t67, #t68, #t69) in #t69);
+  self::expect(5, let final self::MapLike<core::int*, core::int*>* #t71 = map2 in let final core::int* #t72 = 0 in let final core::int* #t73 = self::Extension|[]<core::int*, core::int*>(#t71, #t72) in let final void #t74 = self::Extension|[]=<core::int*, core::int*>(#t71, #t72, #t73.{core::num::+}(1){(core::num*) →* core::int*}) in #t73);
+  self::expect(6, self::Extension|[]<core::int*, core::int*>(map2, 0));
+  self::expect(5, let final self::MapLike<core::int*, core::int*>* #t75 = map2 in let final core::int* #t76 = 0 in let final core::int* #t77 = self::Extension|[]<core::int*, core::int*>(#t75, #t76).{core::num::-}(1){(core::num*) →* core::int*} in let final void #t78 = self::Extension|[]=<core::int*, core::int*>(#t75, #t76, #t77) in #t77);
+  self::expect(5, self::Extension|[]<core::int*, core::int*>(map2, 0));
+}
+static method explicitInferredTypeArguments() → dynamic {
+  self::MapLike<core::int*, core::String*>* map1 = new self::MapLike::•<core::int*, core::String*>();
+  self::expect(null, self::Extension|[]<core::int*, core::String*>(map1, 0));
+  map1.{self::MapLike::put}(0, "0"){(core::int*, core::String*) →* core::String*};
+  self::expect("0", self::Extension|[]<core::int*, core::String*>(map1, 0));
+  self::expect(null, self::Extension|[]<core::int*, core::String*>(map1, 1));
+  self::Extension|[]=<core::int*, core::String*>(map1, 1, "1");
+  self::expect("1", self::Extension|[]<core::int*, core::String*>(map1, 1));
+  self::expect("2", let final self::MapLike<core::int*, core::String*>* #t79 = map1 in let final core::String* #t80 = "2" in let final void #t81 = self::Extension|[]=<core::int*, core::String*>(#t79, 1, #t80) in #t80);
+  self::expect("2", self::Extension|[]<core::int*, core::String*>(map1, 1));
+  let final self::MapLike<core::int*, core::String*>* #t82 = map1 in let final core::int* #t83 = 1 in self::Extension|[]<core::int*, core::String*>(#t82, #t83) == null ?{core::String*} self::Extension|[]=<core::int*, core::String*>(#t82, #t83, "3") : null;
+  self::expect("2", self::Extension|[]<core::int*, core::String*>(map1, 1));
+  self::expect("2", let final self::MapLike<core::int*, core::String*>* #t84 = map1 in let final core::int* #t85 = 1 in let final core::String* #t86 = self::Extension|[]<core::int*, core::String*>(#t84, #t85) in #t86 == null ?{core::String*} let final core::String* #t87 = "4" in let final void #t88 = self::Extension|[]=<core::int*, core::String*>(#t84, #t85, #t87) in #t87 : #t86);
+  self::expect("2", self::Extension|[]<core::int*, core::String*>(map1, 1));
+  let final self::MapLike<core::int*, core::String*>* #t89 = map1 in let final core::int* #t90 = 2 in self::Extension|[]<core::int*, core::String*>(#t89, #t90) == null ?{core::String*} self::Extension|[]=<core::int*, core::String*>(#t89, #t90, "2") : null;
+  self::expect("2", self::Extension|[]<core::int*, core::String*>(map1, 2));
+  self::expect("3", let final self::MapLike<core::int*, core::String*>* #t91 = map1 in let final core::int* #t92 = 3 in let final core::String* #t93 = self::Extension|[]<core::int*, core::String*>(#t91, #t92) in #t93 == null ?{core::String*} let final core::String* #t94 = "3" in let final void #t95 = self::Extension|[]=<core::int*, core::String*>(#t91, #t92, #t94) in #t94 : #t93);
+  self::expect("3", self::Extension|[]<core::int*, core::String*>(map1, 3));
+  self::MapLike<core::int*, core::int*>* map2 = new self::MapLike::•<core::int*, core::int*>();
+  self::expect(1, let final self::MapLike<core::int*, core::int*>* #t96 = map2 in let final core::int* #t97 = 1 in let final void #t98 = self::Extension|[]=<core::int*, core::int*>(#t96, 0, #t97) in #t97);
+  self::expect(3, let final self::MapLike<core::int*, core::int*>* #t99 = map2 in let final core::int* #t100 = 0 in let final core::int* #t101 = self::Extension|[]<core::int*, core::int*>(#t99, #t100).{core::num::+}(2){(core::num*) →* core::int*} in let final void #t102 = self::Extension|[]=<core::int*, core::int*>(#t99, #t100, #t101) in #t101);
+  self::expect(5, let final self::MapLike<core::int*, core::int*>* #t103 = map2 in let final core::int* #t104 = 0 in let final core::int* #t105 = self::Extension|[]<core::int*, core::int*>(#t103, #t104).{core::num::+}(2){(core::num*) →* core::int*} in let final void #t106 = self::Extension|[]=<core::int*, core::int*>(#t103, #t104, #t105) in #t105);
+  self::expect(5, let final self::MapLike<core::int*, core::int*>* #t107 = map2 in let final core::int* #t108 = 0 in let final core::int* #t109 = self::Extension|[]<core::int*, core::int*>(#t107, #t108) in let final void #t110 = self::Extension|[]=<core::int*, core::int*>(#t107, #t108, #t109.{core::num::+}(1){(core::num*) →* core::int*}) in #t109);
+  self::expect(6, self::Extension|[]<core::int*, core::int*>(map2, 0));
+  self::expect(5, let final self::MapLike<core::int*, core::int*>* #t111 = map2 in let final core::int* #t112 = 0 in let final core::int* #t113 = self::Extension|[]<core::int*, core::int*>(#t111, #t112).{core::num::-}(1){(core::num*) →* core::int*} in let final void #t114 = self::Extension|[]=<core::int*, core::int*>(#t111, #t112, #t113) in #t113);
+  self::expect(5, self::Extension|[]<core::int*, core::int*>(map2, 0));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/instance_access.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/instance_access.dart.weak.modular.expect
new file mode 100644
index 0000000..215028e
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/instance_access.dart.weak.modular.expect
@@ -0,0 +1,147 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  field core::int* field;
+  constructor •(core::int* field) → self::Class1*
+    : self::Class1::field = field, super core::Object::•()
+    ;
+  method toString() → core::String*
+    return "Class1(${this.{self::Class1::field}{core::int*}})";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class2 extends core::Object {
+  field core::int* field;
+  constructor •(core::int* field) → self::Class2*
+    : self::Class2::field = field, super core::Object::•()
+    ;
+  method toString() → core::String*
+    return "Class2(${this.{self::Class2::field}{core::int*}})";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension1 on self::Class1* {
+  method method = self::Extension1|method;
+  tearoff method = self::Extension1|get#method;
+  method genericMethod = self::Extension1|genericMethod;
+  tearoff genericMethod = self::Extension1|get#genericMethod;
+  get property = self::Extension1|get#property;
+  set property = self::Extension1|set#property;
+}
+extension Extension2 on self::Class2* {
+  method method = self::Extension2|method;
+  tearoff method = self::Extension2|get#method;
+  method genericMethod = self::Extension2|genericMethod;
+  tearoff genericMethod = self::Extension2|get#genericMethod;
+  get property = self::Extension2|get#property;
+  set property = self::Extension2|set#property;
+}
+static method Extension1|method(lowered final self::Class1* #this) → core::int* {
+  core::print("Extension1.method on ${#this}");
+  return #this.{self::Class1::field}{core::int*};
+}
+static method Extension1|get#method(lowered final self::Class1* #this) → () →* core::int*
+  return () → core::int* => self::Extension1|method(#this);
+static method Extension1|genericMethod<T extends core::num*>(lowered final self::Class1* #this, self::Extension1|genericMethod::T* t) → core::int* {
+  core::print("Extension1.genericMethod<${self::Extension1|genericMethod::T*}>(${t}) on ${#this}");
+  return #this.{self::Class1::field}{core::int*}.{core::num::+}(t){(core::num*) →* core::num*} as{TypeError} core::int*;
+}
+static method Extension1|get#genericMethod(lowered final self::Class1* #this) → <T extends core::num*>(T*) →* core::int*
+  return <T extends core::num*>(T* t) → core::int* => self::Extension1|genericMethod<T*>(#this, t);
+static method Extension1|get#property(lowered final self::Class1* #this) → core::int* {
+  core::print("Extension1.property get on ${#this}");
+  return #this.{self::Class1::field}{core::int*};
+}
+static method Extension1|set#property(lowered final self::Class1* #this, core::int* value) → void {
+  #this.{self::Class1::field} = value;
+  core::print("Extension1.property set(${value}) on ${#this}");
+  value = value.{core::num::+}(1){(core::num*) →* core::int*};
+}
+static method Extension2|method(lowered final self::Class2* #this) → core::int* {
+  core::print("Extension2.method on ${#this}");
+  return #this.{self::Class2::field}{core::int*}.{core::num::+}(3){(core::num*) →* core::int*};
+}
+static method Extension2|get#method(lowered final self::Class2* #this) → () →* core::int*
+  return () → core::int* => self::Extension2|method(#this);
+static method Extension2|genericMethod<T extends core::num*>(lowered final self::Class2* #this, self::Extension2|genericMethod::T* t) → core::int* {
+  core::print("Extension2.genericMethod<${self::Extension2|genericMethod::T*}>(${t}) on ${#this}");
+  return #this.{self::Class2::field}{core::int*}.{core::num::+}(t){(core::num*) →* core::num*}.{core::num::+}(4){(core::num*) →* core::num*} as{TypeError} core::int*;
+}
+static method Extension2|get#genericMethod(lowered final self::Class2* #this) → <T extends core::num*>(T*) →* core::int*
+  return <T extends core::num*>(T* t) → core::int* => self::Extension2|genericMethod<T*>(#this, t);
+static method Extension2|get#property(lowered final self::Class2* #this) → core::int* {
+  core::print("Extension2.property get on ${#this}");
+  return #this.{self::Class2::field}{core::int*}.{core::num::+}(5){(core::num*) →* core::int*};
+}
+static method Extension2|set#property(lowered final self::Class2* #this, core::int* value) → void {
+  core::print("Extension2.property set(${value}) on ${#this}");
+  value = value.{core::num::+}(1){(core::num*) →* core::int*};
+  #this.{self::Class2::field} = value;
+}
+static method main() → dynamic {
+  self::testExtension1();
+  self::testExtension2();
+}
+static method testExtension1() → dynamic {
+  self::Class1* c0 = new self::Class1::•(0);
+  self::Class1* c1 = new self::Class1::•(1);
+  self::expect(0, self::Extension1|method(c0));
+  self::expect(1, self::Extension1|method(c1));
+  self::expect(1, let final self::Class1* #t1 = c1 in #t1 == null ?{core::int*} null : self::Extension1|method(#t1));
+  self::expect(42, self::Extension1|genericMethod<core::int*>(c0, 42));
+  self::expect(43, self::Extension1|genericMethod<core::num*>(c0, 43));
+  self::expect(88, self::Extension1|genericMethod<core::int*>(c1, 87));
+  self::expect(89, self::Extension1|genericMethod<core::num*>(c1, 88));
+  self::expect(0, self::Extension1|get#property(c0));
+  self::expect(0, let final self::Class1* #t2 = c0 in #t2 == null ?{core::int*} null : self::Extension1|get#property(#t2));
+  self::expect(42, let final core::int* #t3 = 42 in let final void #t4 = self::Extension1|set#property(c0, #t3) in #t3);
+  self::expect(1, self::Extension1|get#property(c1));
+  self::expect(87, let final core::int* #t5 = 87 in let final void #t6 = self::Extension1|set#property(c0, #t5) in #t5);
+  self::expect(27, let final core::int* #t7 = let final core::int* #t8 = 27 in let final void #t9 = self::Extension1|set#property(c1, #t8) in #t8 in let final void #t10 = self::Extension1|set#property(c0, #t7) in #t7);
+  self::expect(37, let final core::int* #t11 = let final core::int* #t12 = 37 in let final void #t13 = self::Extension1|set#property(c0, #t12) in #t12 in let final void #t14 = self::Extension1|set#property(c1, #t11) in #t11);
+  self::expect(77, let final core::int* #t15 = let final core::int* #t16 = let final core::int* #t17 = 77 in let final void #t18 = self::Extension1|set#property(c1, #t17) in #t17 in let final void #t19 = self::Extension1|set#property(c0, #t16) in #t16 in let final void #t20 = self::Extension1|set#property(c1, #t15) in #t15);
+  self::expect(67, let final core::int* #t21 = let final core::int* #t22 = let final core::int* #t23 = 67 in let final void #t24 = self::Extension1|set#property(c0, #t23) in #t23 in let final void #t25 = self::Extension1|set#property(c1, #t22) in #t22 in let final void #t26 = self::Extension1|set#property(c0, #t21) in #t21);
+}
+static method testExtension2() → dynamic {
+  self::Class2* c0 = new self::Class2::•(0);
+  self::Class2* c1 = new self::Class2::•(1);
+  self::expect(3, self::Extension2|method(c0));
+  self::expect(3, let final self::Class2* #t27 = c0 in #t27 == null ?{core::int*} null : self::Extension2|method(#t27));
+  self::expect(4, self::Extension2|method(c1));
+  self::expect(46, self::Extension2|genericMethod<core::int*>(c0, 42));
+  self::expect(47, self::Extension2|genericMethod<core::num*>(c0, 43));
+  self::expect(92, self::Extension2|genericMethod<core::int*>(c1, 87));
+  self::expect(93, self::Extension2|genericMethod<core::num*>(c1, 88));
+  self::expect(5, self::Extension2|get#property(c0));
+  self::expect(5, let final self::Class2* #t28 = c0 in #t28 == null ?{core::int*} null : self::Extension2|get#property(#t28));
+  self::expect(42, let final core::int* #t29 = 42 in let final void #t30 = self::Extension2|set#property(c0, #t29) in #t29);
+  self::expect(48, self::Extension2|get#property(c0));
+  self::expect(6, self::Extension2|get#property(c1));
+  self::expect(43, let final core::int* #t31 = 43 in let final void #t32 = self::Extension2|set#property(c1, #t31) in #t31);
+  self::expect(49, self::Extension2|get#property(c1));
+  self::expect(49, let final core::int* #t33 = self::Extension2|get#property(c1) in let final void #t34 = self::Extension2|set#property(c0, #t33) in #t33);
+  self::expect(55, let final core::int* #t35 = self::Extension2|get#property(c0) in let final void #t36 = self::Extension2|set#property(c1, #t35) in #t35);
+  self::expect(61, let final core::int* #t37 = let final core::int* #t38 = self::Extension2|get#property(c1) in let final void #t39 = self::Extension2|set#property(c0, #t38) in #t38 in let final void #t40 = self::Extension2|set#property(c1, #t37) in #t37);
+  self::expect(67, let final core::int* #t41 = let final core::int* #t42 = self::Extension2|get#property(c0) in let final void #t43 = self::Extension2|set#property(c1, #t42) in #t42 in let final void #t44 = self::Extension2|set#property(c0, #t41) in #t41);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/instance_access_of_static.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/instance_access_of_static.dart.weak.modular.expect
new file mode 100644
index 0000000..1dadbb1
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/instance_access_of_static.dart.weak.modular.expect
@@ -0,0 +1,108 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/instance_access_of_static.dart:26:5: Error: The method 'staticMethod' isn't defined for the class 'Class1'.
+//  - 'Class1' is from 'pkg/front_end/testcases/extensions/instance_access_of_static.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'staticMethod'.
+//   c.staticMethod();
+//     ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/instance_access_of_static.dart:27:5: Error: The getter 'staticMethod' isn't defined for the class 'Class1'.
+//  - 'Class1' is from 'pkg/front_end/testcases/extensions/instance_access_of_static.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'staticMethod'.
+//   c.staticMethod;
+//     ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/instance_access_of_static.dart:28:5: Error: The getter 'staticProperty' isn't defined for the class 'Class1'.
+//  - 'Class1' is from 'pkg/front_end/testcases/extensions/instance_access_of_static.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'staticProperty'.
+//   c.staticProperty;
+//     ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/instance_access_of_static.dart:29:5: Error: The setter 'staticProperty' isn't defined for the class 'Class1'.
+//  - 'Class1' is from 'pkg/front_end/testcases/extensions/instance_access_of_static.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'staticProperty'.
+//   c.staticProperty = 42;
+//     ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/instance_access_of_static.dart:30:5: Error: The getter 'staticField' isn't defined for the class 'Class1'.
+//  - 'Class1' is from 'pkg/front_end/testcases/extensions/instance_access_of_static.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'staticField'.
+//   c.staticField;
+//     ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/instance_access_of_static.dart:31:5: Error: The setter 'staticField' isn't defined for the class 'Class1'.
+//  - 'Class1' is from 'pkg/front_end/testcases/extensions/instance_access_of_static.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'staticField'.
+//   c.staticField = 42;
+//     ^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension1 on self::Class1* {
+  static method staticMethod = self::Extension1|staticMethod;
+  static get staticProperty = get self::Extension1|staticProperty;
+  static field staticField = self::Extension1|staticField;
+  static set staticProperty = set self::Extension1|staticProperty;
+}
+static field core::int* Extension1|staticField = 42;
+static method Extension1|staticMethod() → dynamic {
+  core::print("Extension1.staticMethod()");
+}
+static get Extension1|staticProperty() → dynamic {
+  core::print("Extension1.staticProperty()");
+}
+static set Extension1|staticProperty(core::int* value) → void {
+  core::print("Extension1.staticProperty(${value})");
+  value = value.{core::num::+}(1){(core::num*) →* core::int*};
+}
+static method main() → dynamic {
+  self::Class1* c = new self::Class1::•();
+  invalid-expression "pkg/front_end/testcases/extensions/instance_access_of_static.dart:26:5: Error: The method 'staticMethod' isn't defined for the class 'Class1'.
+ - 'Class1' is from 'pkg/front_end/testcases/extensions/instance_access_of_static.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'staticMethod'.
+  c.staticMethod();
+    ^^^^^^^^^^^^" in c{<unresolved>}.staticMethod();
+  invalid-expression "pkg/front_end/testcases/extensions/instance_access_of_static.dart:27:5: Error: The getter 'staticMethod' isn't defined for the class 'Class1'.
+ - 'Class1' is from 'pkg/front_end/testcases/extensions/instance_access_of_static.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'staticMethod'.
+  c.staticMethod;
+    ^^^^^^^^^^^^" in c{<unresolved>}.staticMethod;
+  invalid-expression "pkg/front_end/testcases/extensions/instance_access_of_static.dart:28:5: Error: The getter 'staticProperty' isn't defined for the class 'Class1'.
+ - 'Class1' is from 'pkg/front_end/testcases/extensions/instance_access_of_static.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'staticProperty'.
+  c.staticProperty;
+    ^^^^^^^^^^^^^^" in c{<unresolved>}.staticProperty;
+  invalid-expression "pkg/front_end/testcases/extensions/instance_access_of_static.dart:29:5: Error: The setter 'staticProperty' isn't defined for the class 'Class1'.
+ - 'Class1' is from 'pkg/front_end/testcases/extensions/instance_access_of_static.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'staticProperty'.
+  c.staticProperty = 42;
+    ^^^^^^^^^^^^^^" in c{<unresolved>}.staticProperty = 42;
+  invalid-expression "pkg/front_end/testcases/extensions/instance_access_of_static.dart:30:5: Error: The getter 'staticField' isn't defined for the class 'Class1'.
+ - 'Class1' is from 'pkg/front_end/testcases/extensions/instance_access_of_static.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'staticField'.
+  c.staticField;
+    ^^^^^^^^^^^" in c{<unresolved>}.staticField;
+  invalid-expression "pkg/front_end/testcases/extensions/instance_access_of_static.dart:31:5: Error: The setter 'staticField' isn't defined for the class 'Class1'.
+ - 'Class1' is from 'pkg/front_end/testcases/extensions/instance_access_of_static.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'staticField'.
+  c.staticField = 42;
+    ^^^^^^^^^^^" in c{<unresolved>}.staticField = 42;
+}
diff --git a/pkg/front_end/testcases/extensions/instance_members.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/instance_members.dart.weak.modular.expect
new file mode 100644
index 0000000..d189b6d
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/instance_members.dart.weak.modular.expect
@@ -0,0 +1,89 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  synthetic constructor •() → self::A1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B1<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B1<self::B1::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension A2 on self::A1* {
+  method method1 = self::A2|method1;
+  tearoff method1 = self::A2|get#method1;
+  method method2 = self::A2|method2;
+  tearoff method2 = self::A2|get#method2;
+  method method3 = self::A2|method3;
+  tearoff method3 = self::A2|get#method3;
+  method method4 = self::A2|method4;
+  tearoff method4 = self::A2|get#method4;
+}
+extension B2<T extends core::Object* = dynamic> on self::B1<T*>* {
+  method method1 = self::B2|method1;
+  tearoff method1 = self::B2|get#method1;
+  method method2 = self::B2|method2;
+  tearoff method2 = self::B2|get#method2;
+}
+static method A2|method1(lowered final self::A1* #this) → self::A1* {
+  return #this;
+}
+static method A2|get#method1(lowered final self::A1* #this) → () →* self::A1*
+  return () → self::A1* => self::A2|method1(#this);
+static method A2|method2<T extends core::Object* = dynamic>(lowered final self::A1* #this, self::A2|method2::T* o) → self::A1* {
+  core::print(o);
+  return #this;
+}
+static method A2|get#method2(lowered final self::A1* #this) → <T extends core::Object* = dynamic>(T*) →* self::A1*
+  return <T extends core::Object* = dynamic>(T* o) → self::A1* => self::A2|method2<T*>(#this, o);
+static method A2|method3<T extends core::Object* = dynamic>(lowered final self::A1* #this, [self::A2|method3::T* o = #C1]) → self::A1* {
+  core::print(o);
+  return #this;
+}
+static method A2|get#method3(lowered final self::A1* #this) → <T extends core::Object* = dynamic>([T*]) →* self::A1*
+  return <T extends core::Object* = dynamic>([T* o = #C1]) → self::A1* => self::A2|method3<T*>(#this, o);
+static method A2|method4<T extends core::Object* = dynamic>(lowered final self::A1* #this, {self::A2|method4::T* o = #C1}) → self::A1* {
+  core::print(o);
+  return #this;
+}
+static method A2|get#method4(lowered final self::A1* #this) → <T extends core::Object* = dynamic>({o: T*}) →* self::A1*
+  return <T extends core::Object* = dynamic>({T* o = #C1}) → self::A1* => self::A2|method4<T*>(#this, o: o);
+static method B2|method1<T extends core::Object* = dynamic>(lowered final self::B1<self::B2|method1::T*>* #this) → self::B1<self::B2|method1::T*>* {
+  return #this;
+}
+static method B2|get#method1<T extends core::Object* = dynamic>(lowered final self::B1<self::B2|get#method1::T*>* #this) → () →* self::B1<self::B2|get#method1::T*>*
+  return () → self::B1<self::B2|get#method1::T*>* => self::B2|method1<self::B2|get#method1::T*>(#this);
+static method B2|method2<T extends core::Object* = dynamic, S extends core::Object* = dynamic>(lowered final self::B1<self::B2|method2::T*>* #this, self::B2|method2::S* o) → self::B1<self::B2|method2::T*>* {
+  core::print(o);
+  return #this;
+}
+static method B2|get#method2<T extends core::Object* = dynamic>(lowered final self::B1<self::B2|get#method2::T*>* #this) → <S extends core::Object* = dynamic>(S*) →* self::B1<self::B2|get#method2::T*>*
+  return <S extends core::Object* = dynamic>(S* o) → self::B1<self::B2|get#method2::T*>* => self::B2|method2<self::B2|get#method2::T*, S*>(#this, o);
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/extensions/instance_tearoff.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/instance_tearoff.dart.weak.modular.expect
new file mode 100644
index 0000000..1240994
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/instance_tearoff.dart.weak.modular.expect
@@ -0,0 +1,119 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  field core::int* field;
+  constructor •(core::int* field) → self::Class1*
+    : self::Class1::field = field, super core::Object::•()
+    ;
+  method toString() → core::String*
+    return "Class1(${this.{self::Class1::field}{core::int*}})";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class2 extends core::Object {
+  field core::int* field;
+  constructor •(core::int* field) → self::Class2*
+    : self::Class2::field = field, super core::Object::•()
+    ;
+  method toString() → core::String*
+    return "Class2(${this.{self::Class2::field}{core::int*}})";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension1 on self::Class1* {
+  method method = self::Extension1|method;
+  tearoff method = self::Extension1|get#method;
+  method genericMethod = self::Extension1|genericMethod;
+  tearoff genericMethod = self::Extension1|get#genericMethod;
+}
+extension Extension2 on self::Class2* {
+  method method = self::Extension2|method;
+  tearoff method = self::Extension2|get#method;
+  method genericMethod = self::Extension2|genericMethod;
+  tearoff genericMethod = self::Extension2|get#genericMethod;
+}
+static method Extension1|method(lowered final self::Class1* #this) → core::int* {
+  core::print("Extension1.method on ${#this}");
+  return #this.{self::Class1::field}{core::int*};
+}
+static method Extension1|get#method(lowered final self::Class1* #this) → () →* core::int*
+  return () → core::int* => self::Extension1|method(#this);
+static method Extension1|genericMethod<T extends core::num*>(lowered final self::Class1* #this, self::Extension1|genericMethod::T* t) → core::int* {
+  core::print("Extension1.genericMethod<${self::Extension1|genericMethod::T*}>(${t}) on ${#this}");
+  return #this.{self::Class1::field}{core::int*}.{core::num::+}(t){(core::num*) →* core::num*} as{TypeError} core::int*;
+}
+static method Extension1|get#genericMethod(lowered final self::Class1* #this) → <T extends core::num*>(T*) →* core::int*
+  return <T extends core::num*>(T* t) → core::int* => self::Extension1|genericMethod<T*>(#this, t);
+static method Extension2|method(lowered final self::Class2* #this) → core::int* {
+  core::print("Extension2.method on ${#this}");
+  return #this.{self::Class2::field}{core::int*}.{core::num::+}(2){(core::num*) →* core::int*};
+}
+static method Extension2|get#method(lowered final self::Class2* #this) → () →* core::int*
+  return () → core::int* => self::Extension2|method(#this);
+static method Extension2|genericMethod<T extends core::num*>(lowered final self::Class2* #this, self::Extension2|genericMethod::T* t) → core::int* {
+  core::print("Extension2.genericMethod<${self::Extension2|genericMethod::T*}>(${t}) on ${#this}");
+  return #this.{self::Class2::field}{core::int*}.{core::num::+}(t){(core::num*) →* core::num*}.{core::num::+}(3){(core::num*) →* core::num*} as{TypeError} core::int*;
+}
+static method Extension2|get#genericMethod(lowered final self::Class2* #this) → <T extends core::num*>(T*) →* core::int*
+  return <T extends core::num*>(T* t) → core::int* => self::Extension2|genericMethod<T*>(#this, t);
+static method main() → dynamic {
+  self::testExtension1();
+  self::testExtension2();
+}
+static method testExtension1() → dynamic {
+  self::Class1* c0 = new self::Class1::•(0);
+  self::Class1* c1 = new self::Class1::•(1);
+  () →* core::int* tearOff0 = self::Extension1|get#method(c0);
+  self::expect(0, tearOff0(){() →* core::int*});
+  c0 = new self::Class1::•(4.{core::int::unary-}(){() →* core::int*});
+  self::expect(0, tearOff0(){() →* core::int*});
+  () →* core::int* tearOff1 = self::Extension1|get#method(c1);
+  self::expect(1, tearOff1(){() →* core::int*});
+  c1 = new self::Class1::•(7.{core::int::unary-}(){() →* core::int*});
+  self::expect(1, tearOff1(){() →* core::int*});
+  <T extends core::num*>(T*) →* core::int* genericTearOff0 = self::Extension1|get#genericMethod(c0);
+  self::expect(38, genericTearOff0<core::int*>(42){(core::int*) →* core::int*});
+  self::expect(38, genericTearOff0<core::num*>(42){(core::num*) →* core::int*});
+  <T extends core::num*>(T*) →* core::int* genericTearOff1 = self::Extension1|get#genericMethod(c1);
+  self::expect(35, genericTearOff1<core::int*>(42){(core::int*) →* core::int*});
+  self::expect(35, genericTearOff1<core::num*>(42){(core::num*) →* core::int*});
+}
+static method testExtension2() → dynamic {
+  self::Class2* c0 = new self::Class2::•(0);
+  self::Class2* c1 = new self::Class2::•(1);
+  () →* core::int* tearOff0 = self::Extension2|get#method(c0);
+  self::expect(2, tearOff0(){() →* core::int*});
+  c0 = new self::Class2::•(4.{core::int::unary-}(){() →* core::int*});
+  self::expect(2, tearOff0(){() →* core::int*});
+  () →* core::int* tearOff1 = self::Extension2|get#method(c1);
+  self::expect(3, tearOff1(){() →* core::int*});
+  c1 = new self::Class2::•(7.{core::int::unary-}(){() →* core::int*});
+  self::expect(3, tearOff1(){() →* core::int*});
+  <T extends core::num*>(T*) →* core::int* genericTearOff0 = self::Extension2|get#genericMethod(c0);
+  self::expect(41, genericTearOff0<core::int*>(42){(core::int*) →* core::int*});
+  self::expect(41, genericTearOff0<core::num*>(42){(core::num*) →* core::int*});
+  <T extends core::num*>(T*) →* core::int* genericTearOff1 = self::Extension2|get#genericMethod(c1);
+  self::expect(38, genericTearOff1<core::int*>(42){(core::int*) →* core::int*});
+  self::expect(38, genericTearOff1<core::num*>(42){(core::num*) →* core::int*});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/internal_resolution.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/internal_resolution.dart.weak.modular.expect
new file mode 100644
index 0000000..80f8e09
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/internal_resolution.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int* field = null;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension _extension#0 on self::Class* {
+  get property1 = self::_extension#0|get#property1;
+  set property1 = self::_extension#0|set#property1;
+}
+extension _extension#1 on self::Class* {
+  get property2 = self::_extension#1|get#property2;
+  set property2 = self::_extension#1|set#property2;
+}
+static method _extension#0|get#property1(lowered final self::Class* #this) → core::int*
+  return self::_extension#1|get#property2(#this);
+static method _extension#0|set#property1(lowered final self::Class* #this, core::int* value) → void
+  return #this.{self::Class::field} = value;
+static method _extension#1|get#property2(lowered final self::Class* #this) → core::int*
+  return #this.{self::Class::field}{core::int*};
+static method _extension#1|set#property2(lowered final self::Class* #this, core::int* value) → void
+  return let final core::int* #t1 = value in let final void #t2 = self::_extension#0|set#property1(#this, #t1) in #t1;
+static method main() → dynamic {
+  self::Class* c = new self::Class::•();
+  self::expect(null, self::_extension#0|get#property1(c));
+  self::expect(null, self::_extension#1|get#property2(c));
+  self::expect(42, let final core::int* #t3 = 42 in let final void #t4 = self::_extension#0|set#property1(c, #t3) in #t3);
+  self::expect(42, self::_extension#1|get#property2(c));
+  self::expect(87, let final core::int* #t5 = 87 in let final void #t6 = self::_extension#1|set#property2(c, #t5) in #t5);
+  self::expect(87, self::_extension#0|get#property1(c));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/invalid_explicit_access.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/invalid_explicit_access.dart.weak.modular.expect
new file mode 100644
index 0000000..0dd6942
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/invalid_explicit_access.dart.weak.modular.expect
@@ -0,0 +1,254 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:23:3: Error: Explicit extension application requires exactly 1 positional argument.
+//   Extension().method(null);
+//   ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:24:3: Error: Explicit extension application requires exactly 1 positional argument.
+//   Extension(c1, null).method(null);
+//   ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:25:3: Error: Explicit extension application requires exactly 1 positional argument.
+//   Extension(receiver: c1).method(null);
+//   ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:26:3: Error: Explicit extension application requires exactly 1 positional argument.
+//   Extension(c1, receiver: null).method(null);
+//   ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:27:3: Error: Explicit extension application of extension 'Extension' takes '0' type argument(s).
+//   Extension<int>(c1).method(null);
+//   ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:29:17: Error: Member not found: 'foo'.
+//   Extension(c1).foo;
+//                 ^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:30:17: Error: Setter not found: 'foo'.
+//   Extension(c1).foo = null;
+//                 ^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:31:17: Error: Method not found: 'foo'.
+//   Extension(c1).foo();
+//                 ^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:32:17: Error: Too few positional arguments: 1 required, 0 given.
+//   Extension(c1).method();
+//                 ^
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:8:3: Context: Found this candidate, but the arguments don't match.
+//   method(a) {}
+//   ^^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:36:17: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//   Extension(c1).method(1, 2);
+//                 ^
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:8:3: Context: Found this candidate, but the arguments don't match.
+//   method(a) {}
+//   ^^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:37:17: Error: Too few positional arguments: 1 required, 0 given.
+//   Extension(c1).method(a: 1);
+//                 ^
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:8:3: Context: Found this candidate, but the arguments don't match.
+//   method(a) {}
+//   ^^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:38:27: Error: No named parameter with the name 'a'.
+//   Extension(c1).method(1, a: 2);
+//                           ^
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:8:3: Context: Found this candidate, but the arguments don't match.
+//   method(a) {}
+//   ^^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:39:17: Error: Expected 0 type arguments.
+//   Extension(c1).method<int>(null);
+//                 ^
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:8:3: Context: Found this candidate, but the arguments don't match.
+//   method(a) {}
+//   ^^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:42:3: Error: Explicit extension application requires exactly 1 positional argument.
+//   GenericExtension().method();
+//   ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:43:3: Error: Explicit extension application requires exactly 1 positional argument.
+//   GenericExtension<int>().method();
+//   ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:44:3: Error: Explicit extension application requires exactly 1 positional argument.
+//   GenericExtension(c2, null).method();
+//   ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:45:3: Error: Explicit extension application requires exactly 1 positional argument.
+//   GenericExtension<int>(c2, null).method();
+//   ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:46:3: Error: Explicit extension application requires exactly 1 positional argument.
+//   GenericExtension(receiver: c2).method();
+//   ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:47:3: Error: Explicit extension application requires exactly 1 positional argument.
+//   GenericExtension<int>(receiver: c2).method();
+//   ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:48:3: Error: Explicit extension application requires exactly 1 positional argument.
+//   GenericExtension(c2, receiver: null).method();
+//   ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:49:3: Error: Explicit extension application requires exactly 1 positional argument.
+//   GenericExtension<int>(c2, receiver: null).method();
+//   ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:50:3: Error: Explicit extension application of extension 'GenericExtension' takes '1' type argument(s).
+//   GenericExtension<int, String>(c2).method();
+//   ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:28:13: Error: The argument type 'String' can't be assigned to the parameter type 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/invalid_explicit_access.dart'.
+//   Extension(s).method(null);
+//             ^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:51:20: Error: The argument type 'String' can't be assigned to the parameter type 'GenericClass<dynamic>'.
+//  - 'GenericClass' is from 'pkg/front_end/testcases/extensions/invalid_explicit_access.dart'.
+//   GenericExtension(s).method();
+//                    ^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_access.dart:52:25: Error: The argument type 'String' can't be assigned to the parameter type 'GenericClass<int>'.
+//  - 'GenericClass' is from 'pkg/front_end/testcases/extensions/invalid_explicit_access.dart'.
+//   GenericExtension<int>(s).method();
+//                         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class GenericClass<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::GenericClass<self::GenericClass::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+  method method = self::Extension|method;
+  tearoff method = self::Extension|get#method;
+}
+extension GenericExtension<T extends core::Object* = dynamic> on self::GenericClass<T*>* {
+  method method = self::GenericExtension|method;
+  tearoff method = self::GenericExtension|get#method;
+}
+static method Extension|method(lowered final self::Class* #this, dynamic a) → dynamic {}
+static method Extension|get#method(lowered final self::Class* #this) → (dynamic) →* dynamic
+  return (dynamic a) → dynamic => self::Extension|method(#this, a);
+static method GenericExtension|method<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|method::T*>* #this) → dynamic {}
+static method GenericExtension|get#method<T extends core::Object* = dynamic>(lowered final self::GenericClass<self::GenericExtension|get#method::T*>* #this) → () →* dynamic
+  return () → dynamic => self::GenericExtension|method<self::GenericExtension|get#method::T*>(#this);
+static method main() → dynamic {
+  core::String* s = "";
+  self::Class* c1 = new self::Class::•();
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:23:3: Error: Explicit extension application requires exactly 1 positional argument.
+  Extension().method(null);
+  ^^^^^^^^^"{dynamic}.method(null);
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:24:3: Error: Explicit extension application requires exactly 1 positional argument.
+  Extension(c1, null).method(null);
+  ^^^^^^^^^"{dynamic}.method(null);
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:25:3: Error: Explicit extension application requires exactly 1 positional argument.
+  Extension(receiver: c1).method(null);
+  ^^^^^^^^^"{dynamic}.method(null);
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:26:3: Error: Explicit extension application requires exactly 1 positional argument.
+  Extension(c1, receiver: null).method(null);
+  ^^^^^^^^^"{dynamic}.method(null);
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:27:3: Error: Explicit extension application of extension 'Extension' takes '0' type argument(s).
+  Extension<int>(c1).method(null);
+  ^^^^^^^^^"{dynamic}.method(null);
+  self::Extension|method(invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:28:13: Error: The argument type 'String' can't be assigned to the parameter type 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/invalid_explicit_access.dart'.
+  Extension(s).method(null);
+            ^" in s as{TypeError} self::Class*, null);
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:29:17: Error: Member not found: 'foo'.
+  Extension(c1).foo;
+                ^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:30:17: Error: Setter not found: 'foo'.
+  Extension(c1).foo = null;
+                ^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:31:17: Error: Method not found: 'foo'.
+  Extension(c1).foo();
+                ^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:32:17: Error: Too few positional arguments: 1 required, 0 given.
+  Extension(c1).method();
+                ^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:36:17: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+  Extension(c1).method(1, 2);
+                ^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:37:17: Error: Too few positional arguments: 1 required, 0 given.
+  Extension(c1).method(a: 1);
+                ^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:38:27: Error: No named parameter with the name 'a'.
+  Extension(c1).method(1, a: 2);
+                          ^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:39:17: Error: Expected 0 type arguments.
+  Extension(c1).method<int>(null);
+                ^";
+  self::GenericClass<core::int*>* c2 = new self::GenericClass::•<core::int*>();
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:42:3: Error: Explicit extension application requires exactly 1 positional argument.
+  GenericExtension().method();
+  ^^^^^^^^^^^^^^^^"{dynamic}.method();
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:43:3: Error: Explicit extension application requires exactly 1 positional argument.
+  GenericExtension<int>().method();
+  ^^^^^^^^^^^^^^^^"{dynamic}.method();
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:44:3: Error: Explicit extension application requires exactly 1 positional argument.
+  GenericExtension(c2, null).method();
+  ^^^^^^^^^^^^^^^^"{dynamic}.method();
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:45:3: Error: Explicit extension application requires exactly 1 positional argument.
+  GenericExtension<int>(c2, null).method();
+  ^^^^^^^^^^^^^^^^"{dynamic}.method();
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:46:3: Error: Explicit extension application requires exactly 1 positional argument.
+  GenericExtension(receiver: c2).method();
+  ^^^^^^^^^^^^^^^^"{dynamic}.method();
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:47:3: Error: Explicit extension application requires exactly 1 positional argument.
+  GenericExtension<int>(receiver: c2).method();
+  ^^^^^^^^^^^^^^^^"{dynamic}.method();
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:48:3: Error: Explicit extension application requires exactly 1 positional argument.
+  GenericExtension(c2, receiver: null).method();
+  ^^^^^^^^^^^^^^^^"{dynamic}.method();
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:49:3: Error: Explicit extension application requires exactly 1 positional argument.
+  GenericExtension<int>(c2, receiver: null).method();
+  ^^^^^^^^^^^^^^^^"{dynamic}.method();
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:50:3: Error: Explicit extension application of extension 'GenericExtension' takes '1' type argument(s).
+  GenericExtension<int, String>(c2).method();
+  ^^^^^^^^^^^^^^^^"{dynamic}.method();
+  self::GenericExtension|method<dynamic>(invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:51:20: Error: The argument type 'String' can't be assigned to the parameter type 'GenericClass<dynamic>'.
+ - 'GenericClass' is from 'pkg/front_end/testcases/extensions/invalid_explicit_access.dart'.
+  GenericExtension(s).method();
+                   ^" in s as{TypeError} self::GenericClass<dynamic>*);
+  self::GenericExtension|method<core::int*>(invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_access.dart:52:25: Error: The argument type 'String' can't be assigned to the parameter type 'GenericClass<int>'.
+ - 'GenericClass' is from 'pkg/front_end/testcases/extensions/invalid_explicit_access.dart'.
+  GenericExtension<int>(s).method();
+                        ^" in s as{TypeError} self::GenericClass<core::int*>*);
+}
diff --git a/pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart.weak.modular.expect
new file mode 100644
index 0000000..94d05b9
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart.weak.modular.expect
@@ -0,0 +1,104 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:18:16: Error: Method not found: 'method'.
+//   Extension(s).method();
+//                ^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:19:16: Error: Member not found: 'method'.
+//   Extension(s).method;
+//                ^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:20:16: Error: Setter not found: 'method'.
+//   Extension(s).method = 42;
+//                ^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:21:16: Error: Member not found: 'getter'.
+//   Extension(s).getter;
+//                ^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:22:16: Error: Setter not found: 'getter'.
+//   Extension(s).getter = 42;
+//                ^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:23:16: Error: Member not found: 'setter'.
+//   Extension(s).setter;
+//                ^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:24:16: Error: Setter not found: 'setter'.
+//   Extension(s).setter = 42;
+//                ^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:25:16: Error: Member not found: 'property'.
+//   Extension(s).property;
+//                ^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:26:16: Error: Setter not found: 'property'.
+//   Extension(s).property = 42;
+//                ^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:27:16: Error: Member not found: 'field'.
+//   Extension(s).field;
+//                ^^^^^
+//
+// pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:28:16: Error: Setter not found: 'field'.
+//   Extension(s).field = 42;
+//                ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+extension Extension on core::String* {
+  static method method = self::Extension|method;
+  static get getter = get self::Extension|getter;
+  static get property = get self::Extension|property;
+  static field field = self::Extension|field;
+  static set setter = set self::Extension|setter;
+  static set property = set self::Extension|property;
+}
+static field dynamic Extension|field;
+static method Extension|method() → dynamic {}
+static get Extension|getter() → dynamic
+  return null;
+static set Extension|setter(dynamic _) → void {}
+static get Extension|property() → dynamic
+  return null;
+static set Extension|property(dynamic _) → void {}
+static method main() → dynamic {}
+static method errors() → dynamic {
+  core::String* s = "";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:18:16: Error: Method not found: 'method'.
+  Extension(s).method();
+               ^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:19:16: Error: Member not found: 'method'.
+  Extension(s).method;
+               ^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:20:16: Error: Setter not found: 'method'.
+  Extension(s).method = 42;
+               ^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:21:16: Error: Member not found: 'getter'.
+  Extension(s).getter;
+               ^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:22:16: Error: Setter not found: 'getter'.
+  Extension(s).getter = 42;
+               ^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:23:16: Error: Member not found: 'setter'.
+  Extension(s).setter;
+               ^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:24:16: Error: Setter not found: 'setter'.
+  Extension(s).setter = 42;
+               ^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:25:16: Error: Member not found: 'property'.
+  Extension(s).property;
+               ^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:26:16: Error: Setter not found: 'property'.
+  Extension(s).property = 42;
+               ^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:27:16: Error: Member not found: 'field'.
+  Extension(s).field;
+               ^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/invalid_explicit_static_access.dart:28:16: Error: Setter not found: 'field'.
+  Extension(s).field = 42;
+               ^^^^^";
+}
diff --git a/pkg/front_end/testcases/extensions/issue38600.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue38600.dart.weak.modular.expect
new file mode 100644
index 0000000..373bda2
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue38600.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/issue38600.dart:7:1: Error: Expected 'on' after this.
+// extension try<T> on Class<T> {}
+// ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38600.dart:7:11: Error: Expected a type, but got 'try'.
+// extension try<T> on Class<T> {}
+//           ^^^
+//
+// pkg/front_end/testcases/extensions/issue38600.dart:7:11: Error: A extension declaration must have a body, even if it is empty.
+// Try adding an empty body.
+// extension try<T> on Class<T> {}
+//           ^^^
+//
+// pkg/front_end/testcases/extensions/issue38600.dart:7:11: Error: 'try' can't be used as an identifier because it's a keyword.
+// Try renaming this to be an identifier that isn't a keyword.
+// extension try<T> on Class<T> {}
+//           ^^^
+//
+// pkg/front_end/testcases/extensions/issue38600.dart:7:11: Error: A function declaration needs an explicit list of parameters.
+// Try adding a parameter list to the function declaration.
+// extension try<T> on Class<T> {}
+//           ^^^
+//
+// pkg/front_end/testcases/extensions/issue38600.dart:7:18: Error: Expected '{' before this.
+// extension try<T> on Class<T> {}
+//                  ^^
+//
+// pkg/front_end/testcases/extensions/issue38600.dart:7:21: Error: A function declaration needs an explicit list of parameters.
+// Try adding a parameter list to the function declaration.
+// extension try<T> on Class<T> {}
+//                     ^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38600.dart:7:21: Error: 'Class' is already declared in this scope.
+// extension try<T> on Class<T> {}
+//                     ^^^^^
+// pkg/front_end/testcases/extensions/issue38600.dart:5:7: Context: Previous declaration of 'Class'.
+// class Class<T> {}
+//       ^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38600.dart:7:18: Error: Type 'on' not found.
+// extension try<T> on Class<T> {}
+//                  ^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension _extension#0 on invalid-type {
+}
+static method try<T extends core::Object* = dynamic>() → dynamic {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/issue38712.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue38712.dart.weak.modular.expect
new file mode 100644
index 0000000..464cf79
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue38712.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/issue38712.dart:5:11: Error: Expected 'on' after this.
+// extension C {
+//           ^
+//
+// pkg/front_end/testcases/extensions/issue38712.dart:5:13: Error: Expected a type, but got '{'.
+// extension C {
+//             ^
+//
+import self as self;
+
+extension C on invalid-type {
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/extensions/issue38713.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue38713.dart.weak.modular.expect
new file mode 100644
index 0000000..8dbe072
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue38713.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/issue38713.dart:7:19: Error: Conflicts with the implicit setter of the field 'property2'.
+//   static void set property2(int x) {}
+//                   ^
+//
+// pkg/front_end/testcases/extensions/issue38713.dart:6:14: Error: Conflicts with setter 'property2'.
+//   static int property2;
+//              ^
+//
+// pkg/front_end/testcases/extensions/issue38713.dart:9:19: Error: Conflicts with member 'property3'.
+//   static void set property3(int x) {}
+//                   ^
+//
+// pkg/front_end/testcases/extensions/issue38713.dart:10:11: Error: Conflicts with setter 'property3'.
+//   int get property3 => 1;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+extension C on core::int* {
+  static field property2 = self::C|property2;
+  get property3 = self::C|get#property3;
+  static set property3 = set self::C|property3;
+}
+static field core::int* C|property2;
+static set C|property3(core::int* x) → void {}
+static method C|get#property3(lowered final core::int* #this) → core::int*
+  return 1;
+static method main() → void {
+  self::C|property2;
+  self::C|property2 = 42;
+  self::C|property3 = 42;
+  self::C|get#property3(42);
+}
diff --git a/pkg/front_end/testcases/extensions/issue38745.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue38745.dart.weak.modular.expect
new file mode 100644
index 0000000..aa7f4d8
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue38745.dart.weak.modular.expect
@@ -0,0 +1,196 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:9:7: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int field;
+//       ^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:11:13: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   final int property = 42;
+//             ^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:15:13: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   final int property2 = 42;
+//             ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:17:19: Error: Conflicts with member 'property2'.
+//   static void set property2(int value) {}
+//                   ^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:15:13: Error: Conflicts with setter 'property2'.
+//   final int property2 = 42;
+//             ^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:20:5: Error: Undefined name 'field'.
+//     field;
+//     ^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:21:5: Error: Setter not found: 'field'.
+//     field = 23;
+//     ^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:22:5: Error: Getter not found: 'property'.
+//     property;
+//     ^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:24:5: Error: Undefined name 'property2'.
+//     property2;
+//     ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:25:5: Error: Setter not found: 'property2'.
+//     property2 = 23;
+//     ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:40:10: Error: Member not found: 'field'.
+//   ext(c).field;
+//          ^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:41:10: Error: Setter not found: 'field'.
+//   ext(c).field = 23;
+//          ^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:42:10: Error: Getter not found: 'property'.
+//   ext(c).property;
+//          ^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:44:10: Error: Member not found: 'property2'.
+//   ext(c).property2;
+//          ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:45:10: Error: Setter not found: 'property2'.
+//   ext(c).property2 = 23;
+//          ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:34:5: Error: The getter 'field' isn't defined for the class 'C<int>'.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/issue38745.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'field'.
+//   c.field;
+//     ^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:35:5: Error: The setter 'field' isn't defined for the class 'C<int>'.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/issue38745.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'field'.
+//   c.field = 23;
+//     ^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:36:5: Error: The getter 'property' isn't defined for the class 'C<int>'.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/issue38745.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'property'.
+//   c.property;
+//     ^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:38:5: Error: The getter 'property2' isn't defined for the class 'C<int>'.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/issue38745.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'property2'.
+//   c.property2;
+//     ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38745.dart:39:5: Error: The setter 'property2' isn't defined for the class 'C<int>'.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/issue38745.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'property2'.
+//   c.property2 = 23;
+//     ^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension ext<T extends core::Object* = dynamic> on self::C<T*>* {
+  field field = self::ext|field;
+  field property = self::ext|property;
+  field property2 = self::ext|property2;
+  method method = self::ext|method;
+  tearoff method = self::ext|get#method;
+  set property = self::ext|set#property;
+  static set property2 = set self::ext|property2;
+}
+static field core::int* ext|field;
+static final field core::int* ext|property = 42;
+static final field core::int* ext|property2 = 42;
+static method ext|set#property<T extends core::Object* = dynamic>(lowered final self::C<self::ext|set#property::T*>* #this, core::int* value) → void {}
+static set ext|property2(core::int* value) → void {}
+static method ext|method<T extends core::Object* = dynamic>(lowered final self::C<self::ext|method::T*>* #this) → dynamic {
+  invalid-expression "pkg/front_end/testcases/extensions/issue38745.dart:20:5: Error: Undefined name 'field'.
+    field;
+    ^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/issue38745.dart:21:5: Error: Setter not found: 'field'.
+    field = 23;
+    ^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/issue38745.dart:22:5: Error: Getter not found: 'property'.
+    property;
+    ^^^^^^^^";
+  self::ext|set#property<self::ext|method::T*>(#this, 23);
+  invalid-expression "pkg/front_end/testcases/extensions/issue38745.dart:24:5: Error: Undefined name 'property2'.
+    property2;
+    ^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/issue38745.dart:25:5: Error: Setter not found: 'property2'.
+    property2 = 23;
+    ^^^^^^^^^";
+}
+static method ext|get#method<T extends core::Object* = dynamic>(lowered final self::C<self::ext|get#method::T*>* #this) → () →* dynamic
+  return () → dynamic => self::ext|method<self::ext|get#method::T*>(#this);
+static method main() → dynamic {}
+static method errors() → dynamic {
+  self::C<core::int*>* c = new self::C::•<core::int*>();
+  invalid-expression "pkg/front_end/testcases/extensions/issue38745.dart:34:5: Error: The getter 'field' isn't defined for the class 'C<int>'.
+ - 'C' is from 'pkg/front_end/testcases/extensions/issue38745.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'field'.
+  c.field;
+    ^^^^^" in c{<unresolved>}.field;
+  invalid-expression "pkg/front_end/testcases/extensions/issue38745.dart:35:5: Error: The setter 'field' isn't defined for the class 'C<int>'.
+ - 'C' is from 'pkg/front_end/testcases/extensions/issue38745.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'field'.
+  c.field = 23;
+    ^^^^^" in c{<unresolved>}.field = 23;
+  invalid-expression "pkg/front_end/testcases/extensions/issue38745.dart:36:5: Error: The getter 'property' isn't defined for the class 'C<int>'.
+ - 'C' is from 'pkg/front_end/testcases/extensions/issue38745.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'property'.
+  c.property;
+    ^^^^^^^^" in c{<unresolved>}.property;
+  self::ext|set#property<core::int*>(c, 23);
+  invalid-expression "pkg/front_end/testcases/extensions/issue38745.dart:38:5: Error: The getter 'property2' isn't defined for the class 'C<int>'.
+ - 'C' is from 'pkg/front_end/testcases/extensions/issue38745.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'property2'.
+  c.property2;
+    ^^^^^^^^^" in c{<unresolved>}.property2;
+  invalid-expression "pkg/front_end/testcases/extensions/issue38745.dart:39:5: Error: The setter 'property2' isn't defined for the class 'C<int>'.
+ - 'C' is from 'pkg/front_end/testcases/extensions/issue38745.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'property2'.
+  c.property2 = 23;
+    ^^^^^^^^^" in c{<unresolved>}.property2 = 23;
+  invalid-expression "pkg/front_end/testcases/extensions/issue38745.dart:40:10: Error: Member not found: 'field'.
+  ext(c).field;
+         ^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/issue38745.dart:41:10: Error: Setter not found: 'field'.
+  ext(c).field = 23;
+         ^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/issue38745.dart:42:10: Error: Getter not found: 'property'.
+  ext(c).property;
+         ^^^^^^^^";
+  self::ext|set#property<core::int*>(c, 23);
+  invalid-expression "pkg/front_end/testcases/extensions/issue38745.dart:44:10: Error: Member not found: 'property2'.
+  ext(c).property2;
+         ^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/issue38745.dart:45:10: Error: Setter not found: 'property2'.
+  ext(c).property2 = 23;
+         ^^^^^^^^^";
+  self::ext|method<core::int*>(c);
+}
diff --git a/pkg/front_end/testcases/extensions/issue38750.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue38750.dart.weak.modular.expect
new file mode 100644
index 0000000..4dbcce1
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue38750.dart.weak.modular.expect
@@ -0,0 +1,118 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/issue38750.dart:13:5: Error: Member not found: 'C._staticFoo'.
+//   C._staticFoo();
+//     ^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/issue38750.dart:12:5: Error: The method '_foo' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/issue38750_lib1.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named '_foo'.
+//   c._foo();
+//     ^^^^
+//
+// pkg/front_end/testcases/extensions/issue38750.dart:16:5: Error: The method '_bar' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/issue38750_lib1.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named '_bar'.
+//   c._bar();
+//     ^^^^
+//
+import self as self;
+import "issue38750_lib1.dart" as iss;
+
+import "org-dartlang-testcase:///issue38750_lib1.dart";
+import "org-dartlang-testcase:///issue38750_lib2.dart";
+
+static method main() → dynamic {}
+static method errors() → dynamic {
+  iss::C* c = new iss::C::•();
+  invalid-expression "pkg/front_end/testcases/extensions/issue38750.dart:12:5: Error: The method '_foo' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/extensions/issue38750_lib1.dart'.
+Try correcting the name to the name of an existing method, or defining a method named '_foo'.
+  c._foo();
+    ^^^^" in c{<unresolved>}._foo();
+  invalid-expression "pkg/front_end/testcases/extensions/issue38750.dart:13:5: Error: Member not found: 'C._staticFoo'.
+  C._staticFoo();
+    ^^^^^^^^^^";
+  c.{iss::C::foo}(){() →* dynamic};
+  iss::C::staticFoo();
+  invalid-expression "pkg/front_end/testcases/extensions/issue38750.dart:16:5: Error: The method '_bar' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/extensions/issue38750_lib1.dart'.
+Try correcting the name to the name of an existing method, or defining a method named '_bar'.
+  c._bar();
+    ^^^^" in c{<unresolved>}._bar();
+}
+
+library;
+import self as iss;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → iss::C*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic
+    return this.{iss::C::_foo}(){() →* dynamic};
+  method _foo() → dynamic {
+    try {
+      throw "producing a stack trace";
+    }
+    on dynamic catch(final dynamic e, final core::StackTrace* s) {
+      core::print(s);
+    }
+  }
+  static method _staticFoo() → dynamic {
+    core::print("_staticFoo");
+  }
+  static method staticFoo() → dynamic
+    return iss::C::_staticFoo();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension ext on iss::C* {
+  method _bar = iss::ext|_bar;
+  tearoff _bar = iss::ext|get#_bar;
+}
+static method ext|_bar(lowered final iss::C* #this) → dynamic {
+  try {
+    throw "producing a stack trace";
+  }
+  on dynamic catch(final dynamic e, final core::StackTrace* s) {
+    core::print(s);
+  }
+}
+static method ext|get#_bar(lowered final iss::C* #this) → () →* dynamic
+  return () → dynamic => iss::ext|_bar(#this);
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/issue38750_lib2.dart:9:5: Error: The method '_bar' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/extensions/issue38750_lib1.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named '_bar'.
+//   c._bar();
+//     ^^^^
+//
+import self as self2;
+import "issue38750_lib1.dart" as iss;
+
+import "org-dartlang-testcase:///issue38750_lib1.dart";
+
+static method errors() → dynamic {
+  iss::C* c = new iss::C::•();
+  invalid-expression "pkg/front_end/testcases/extensions/issue38750_lib2.dart:9:5: Error: The method '_bar' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/extensions/issue38750_lib1.dart'.
+Try correcting the name to the name of an existing method, or defining a method named '_bar'.
+  c._bar();
+    ^^^^" in c{<unresolved>}._bar();
+}
diff --git a/pkg/front_end/testcases/extensions/issue38755.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue38755.dart.weak.modular.expect
new file mode 100644
index 0000000..8be9036
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue38755.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+extension A<T extends core::Object* = dynamic> on core::List<T*>* {
+  method myMap = self::A|myMap;
+  tearoff myMap = self::A|get#myMap;
+}
+static final field core::List<core::String*>* list = self::A|myMap<core::String*, core::String*>(<core::String*>["a", "b", "c"], (core::String* it) → core::String* => it);
+static method A|myMap<T extends core::Object* = dynamic, R extends core::Object* = dynamic>(lowered final core::List<self::A|myMap::T*>* #this, (self::A|myMap::T*) →* self::A|myMap::R* block) → core::List<self::A|myMap::R*>* {
+  return #this.{core::Iterable::map}<self::A|myMap::R*>(block){((self::A|myMap::T*) →* self::A|myMap::R*) →* core::Iterable<self::A|myMap::R*>*}.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<self::A|myMap::R*>*};
+}
+static method A|get#myMap<T extends core::Object* = dynamic>(lowered final core::List<self::A|get#myMap::T*>* #this) → <R extends core::Object* = dynamic>((self::A|get#myMap::T*) →* R*) →* core::List<R*>*
+  return <R extends core::Object* = dynamic>((self::A|get#myMap::T*) →* R* block) → core::List<R*>* => self::A|myMap<self::A|get#myMap::T*, R*>(#this, block);
+static method main() → dynamic {
+  core::print(self::list);
+}
diff --git a/pkg/front_end/testcases/extensions/issue38915.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue38915.dart.weak.modular.expect
new file mode 100644
index 0000000..ab76811
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue38915.dart.weak.modular.expect
@@ -0,0 +1,67 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+  method method1 = self::Extension|method1;
+  tearoff method1 = self::Extension|get#method1;
+  method method2 = self::Extension|method2;
+  tearoff method2 = self::Extension|get#method2;
+  method method3 = self::Extension|method3;
+  tearoff method3 = self::Extension|get#method3;
+  method method4 = self::Extension|method4;
+  tearoff method4 = self::Extension|get#method4;
+}
+static method Extension|method1(lowered final self::Class* #this, {core::bool* b = #C1, core::String* s = #C2}) → void
+  return null;
+static method Extension|get#method1(lowered final self::Class* #this) → ({b: core::bool*, s: core::String*}) →* void
+  return ({core::bool* b = #C1, core::String* s = #C2}) → void => self::Extension|method1(#this, b: b, s: s);
+static method Extension|method2(lowered final self::Class* #this, [core::bool* b = #C1, core::String* s = #C2]) → void
+  return null;
+static method Extension|get#method2(lowered final self::Class* #this) → ([core::bool*, core::String*]) →* void
+  return ([core::bool* b = #C1, core::String* s = #C2]) → void => self::Extension|method2(#this, b, s);
+static method Extension|method3(lowered final self::Class* #this, core::int* i, {core::bool* b = #C1, core::String* s = #C2}) → void {}
+static method Extension|get#method3(lowered final self::Class* #this) → (core::int*, {b: core::bool*, s: core::String*}) →* void
+  return (core::int* i, {core::bool* b = #C1, core::String* s = #C2}) → void => self::Extension|method3(#this, i, b: b, s: s);
+static method Extension|method4(lowered final self::Class* #this, core::int* i, [core::bool* b = #C1, core::String* s = #C2]) → void {}
+static method Extension|get#method4(lowered final self::Class* #this) → (core::int*, [core::bool*, core::String*]) →* void
+  return (core::int* i, [core::bool* b = #C1, core::String* s = #C2]) → void => self::Extension|method4(#this, i, b, s);
+static method main() → dynamic {
+  self::Class* c = new self::Class::•();
+  self::Extension|method1(c);
+  self::Extension|method1(c, s: "foo");
+  self::Extension|method1(c, b: true);
+  self::Extension|method1(c, b: true, s: "foo");
+  self::Extension|method1(c, s: "foo", b: true);
+  self::Extension|method2(c);
+  self::Extension|method2(c, true);
+  self::Extension|method2(c, true, "foo");
+  self::Extension|method3(c, 42);
+  self::Extension|method3(c, 42, s: "foo");
+  self::Extension|method3(c, 42, b: true);
+  self::Extension|method3(c, 42, b: true, s: "foo");
+  self::Extension|method3(c, 42, s: "foo", b: true);
+  self::Extension|method4(c, 42);
+  self::Extension|method4(c, 42, true);
+  self::Extension|method4(c, 42, true, "foo");
+}
+
+constants  {
+  #C1 = false
+  #C2 = ", "
+}
diff --git a/pkg/front_end/testcases/extensions/issue39527.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue39527.dart.weak.modular.expect
new file mode 100644
index 0000000..7d9415b
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue39527.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field core::int* value = 0;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension1 on self::C* {
+  operator [] = self::Extension1|[];
+  operator []= = self::Extension1|[]=;
+  operator - = self::Extension1|-;
+}
+static method Extension1|[](lowered final self::C* #this, core::int* index) → self::C*
+  return let final self::C* #t1 = #this in block {
+    #t1.{self::C::value} = #t1.{self::C::value}{core::int*}.{core::num::+}(index.{core::num::+}(1){(core::num*) →* core::int*}){(core::num*) →* core::int*};
+  } =>#t1;
+static method Extension1|[]=(lowered final self::C* #this, core::int* index, self::C* other) → void
+  return #this.{self::C::value} = #this.{self::C::value}{core::int*}.{core::num::+}(other.{self::C::value}{core::int*}.{core::num::+}(index){(core::num*) →* core::int*}.{core::num::+}(1){(core::num*) →* core::int*}){(core::num*) →* core::int*};
+static method Extension1|-(lowered final self::C* #this, core::int* val) → self::C*
+  return #this;
+static method main() → dynamic {
+  self::C* c = new self::C::•();
+  let final self::C* #t2 = c in let final core::int* #t3 = 42 in let final self::C* #t4 = self::Extension1|-(self::Extension1|[](#t2, #t3), 1) in let final void #t5 = self::Extension1|[]=(#t2, #t3, #t4) in #t4;
+  let final self::C* #t6 = c in let final core::int* #t7 = 42 in self::Extension1|[]=(#t6, #t7, self::Extension1|-(self::Extension1|[](#t6, #t7), 1));
+  self::Extension1|[]=(c, 42, self::Extension1|-(self::Extension1|[](c, 42), 1));
+}
diff --git a/pkg/front_end/testcases/extensions/issue39889.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue39889.dart.weak.modular.expect
new file mode 100644
index 0000000..3d65b0f
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue39889.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension E on self::C* {
+  method f = self::E|f;
+  tearoff f = self::E|get#f;
+}
+static method E|f(lowered final self::C* #this, core::String* b) → void {}
+static method E|get#f(lowered final self::C* #this) → (core::String*) →* void
+  return (core::String* b) → void => self::E|f(#this, b);
+static method main() → void {
+  dynamic b = "456";
+  self::C* c = new self::C::•();
+  self::E|f(c, b as{TypeError,ForDynamic} core::String*);
+}
diff --git a/pkg/front_end/testcases/extensions/issue39938/issue39938.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue39938/issue39938.dart.weak.modular.expect
new file mode 100644
index 0000000..1c4dd76
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue39938/issue39938.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library;
+import self as self;
+import "issue39938_lib.dart" as iss;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue39938_lib.dart";
+
+static method main() → dynamic {
+  self::expect(true, iss::Extension|+(true, true));
+  self::expect(true, iss::Extension|+(true, false));
+  self::expect(true, iss::Extension|+(false, true));
+  self::expect(false, iss::Extension|+(false, false));
+  self::expect(true, iss::Extension|+(true, true));
+  self::expect(true, iss::Extension|+(true, false));
+  self::expect(true, iss::Extension|+(false, true));
+  self::expect(false, iss::Extension|+(false, false));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, actual ${actual}.";
+}
diff --git a/pkg/front_end/testcases/extensions/issue40596.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue40596.dart.weak.modular.expect
new file mode 100644
index 0000000..4f80fad
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue40596.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+extension Extension<T extends core::Object* = dynamic> on asy::Stream<T*>* {
+  method call = self::Extension|call;
+  tearoff call = self::Extension|get#call;
+}
+static method main() → void {
+  asy::StreamController<core::String*>* controller = asy::StreamController::•<core::String*>();
+  let final asy::StreamController<core::String*>* #t1 = controller in let final (dynamic) →* Null #t2 = (dynamic s) → Null {
+    core::print(s);
+  } in self::Extension|call<core::String*>(#t1.{asy::StreamController::stream}{asy::Stream<core::String*>*}, #t2);
+}
+static method Extension|call<T extends core::Object* = dynamic>(lowered final asy::Stream<self::Extension|call::T*>* #this, core::Function* onData) → asy::StreamSubscription<self::Extension|call::T*>* {
+  return #this.{asy::Stream::listen}((self::Extension|call::T* d) → Null {
+    onData(d);
+  }){((self::Extension|call::T*) →* void, {cancelOnError: core::bool*, onDone: () →* void, onError: core::Function*}) →* asy::StreamSubscription<self::Extension|call::T*>*};
+}
+static method Extension|get#call<T extends core::Object* = dynamic>(lowered final asy::Stream<self::Extension|get#call::T*>* #this) → (core::Function*) →* asy::StreamSubscription<self::Extension|get#call::T*>*
+  return (core::Function* onData) → asy::StreamSubscription<self::Extension|get#call::T*>* => self::Extension|call<self::Extension|get#call::T*>(#this, onData);
diff --git a/pkg/front_end/testcases/extensions/issue40713.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue40713.dart.weak.modular.expect
new file mode 100644
index 0000000..568f207
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue40713.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/issue40713.dart:22:8: Error: 'safeFirst' isn't a function or method and can't be invoked.
+//   list.safeFirst();
+//        ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/issue40713.dart:24:18: Error: Too few positional arguments: 1 required, 0 given.
+//   list2.safeFirst();
+//                  ^
+//
+import self as self;
+import "dart:core" as core;
+
+extension SafeAccess<T extends core::Object* = dynamic> on core::Iterable<T*>* {
+  get safeFirst = self::SafeAccess|get#safeFirst;
+}
+static method SafeAccess|get#safeFirst<T extends core::Object* = dynamic>(lowered final core::Iterable<self::SafeAccess|get#safeFirst::T*>* #this) → self::SafeAccess|get#safeFirst::T* {
+  return #this.{core::Iterable::isNotEmpty}{core::bool*} ?{self::SafeAccess|get#safeFirst::T*} #this.{core::Iterable::first}{self::SafeAccess|get#safeFirst::T*} : null;
+}
+static method main() → dynamic {}
+static method test() → void {
+  final core::List<dynamic>* list = <dynamic>[];
+  self::SafeAccess|get#safeFirst<dynamic>(list){dynamic}.call();
+  final core::List<(core::int*) →* void>* list2 = <(core::int*) →* void>[];
+  self::SafeAccess|get#safeFirst<(core::int*) →* void>(list2)(0){(core::int*) →* void};
+}
+static method errors() → void {
+  final core::List<core::Object*>* list = <core::Object*>[];
+  invalid-expression "pkg/front_end/testcases/extensions/issue40713.dart:22:8: Error: 'safeFirst' isn't a function or method and can't be invoked.
+  list.safeFirst();
+       ^^^^^^^^^" in self::SafeAccess|get#safeFirst<core::Object*>(list){<unresolved>}.call();
+  final core::List<(core::int*) →* void>* list2 = <(core::int*) →* void>[];
+  invalid-expression "pkg/front_end/testcases/extensions/issue40713.dart:24:18: Error: Too few positional arguments: 1 required, 0 given.
+  list2.safeFirst();
+                 ^" in self::SafeAccess|get#safeFirst<(core::int*) →* void>(list2){<inapplicable>}.();
+}
diff --git a/pkg/front_end/testcases/extensions/issue40816.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue40816.dart.weak.modular.expect
new file mode 100644
index 0000000..70c933c
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue40816.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension _extension#0 on self::A* {
+  method foo = self::_extension#0|foo;
+  tearoff foo = self::_extension#0|get#foo;
+}
+static method _extension#0|foo(lowered final self::A* #this, self::A* a, self::B* b) → void {}
+static method _extension#0|get#foo(lowered final self::A* #this) → (self::A*, self::B*) →* void
+  return (self::A* a, self::B* b) → void => self::_extension#0|foo(#this, a, b);
+static method main() → void {
+  dynamic a = new self::A::•();
+  dynamic b = new self::B::•();
+  self::_extension#0|foo(new self::A::•(), a as{TypeError,ForDynamic} self::A*, b as{TypeError,ForDynamic} self::B*);
+}
diff --git a/pkg/front_end/testcases/extensions/issue43218.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue43218.dart.weak.modular.expect
new file mode 100644
index 0000000..8f03ff9
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue43218.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/issue43218.dart:24:10: Error: The setter 'id' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'id'.
+//   Ext(c).id++;
+//          ^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field core::int* value;
+  constructor •() → self::C*
+    : self::C::value = 0, super core::Object::•() {}
+  method init() → dynamic {
+    this.{self::C::value} = 0;
+  }
+  get id() → core::int*
+    return this.{self::C::value}{core::int*};
+  set id(core::int* v) → void {
+    this.{self::C::value} = v;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Ext on self::C* {
+  get id = self::Ext|get#id;
+}
+static method Ext|get#id(lowered final self::C* #this) → core::int*
+  return #this.{self::C::value}{core::int*}.{core::num::+}(1){(core::num*) →* core::int*};
+static method test() → dynamic {
+  self::C* c = new self::C::•();
+  let final self::C* #t1 = c in invalid-expression "pkg/front_end/testcases/extensions/issue43218.dart:24:10: Error: The setter 'id' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'id'.
+  Ext(c).id++;
+         ^^" in #t1{<unresolved>}.id = self::Ext|get#id(#t1).{core::num::+}(1){(core::num*) →* core::int*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/issue44003.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue44003.dart.weak.modular.expect
new file mode 100644
index 0000000..a8d4f63
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue44003.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/issue44003.dart:14:8: Error: 'foo' is already declared in this scope.
+//   void foo(String baz, int a) {
+//        ^^^
+// pkg/front_end/testcases/extensions/issue44003.dart:10:8: Context: Previous declaration of 'foo'.
+//   void foo(String bar) {
+//        ^^^
+//
+// pkg/front_end/testcases/extensions/issue44003.dart:6:8: Error: The method 'foo' isn't defined for the class 'List<String>'.
+//  - 'List' is from 'dart:core'.
+// Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+//   args.foo('1', 2);
+//        ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+extension _extension#0 on core::List<core::String*>* {
+  method foo = self::_extension#0|foo;
+  tearoff foo = self::_extension#0|get#foo;
+}
+static method test(core::List<core::String*>* args) → void {
+  invalid-expression "pkg/front_end/testcases/extensions/issue44003.dart:6:8: Error: The method 'foo' isn't defined for the class 'List<String>'.
+ - 'List' is from 'dart:core'.
+Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+  args.foo('1', 2);
+       ^^^" in args{<unresolved>}.foo("1", 2);
+}
+static method _extension#0|foo(lowered final core::List<core::String*>* #this, core::String* bar) → void {
+  core::print(1);
+}
+static method _extension#0|get#foo(lowered final core::List<core::String*>* #this) → (core::String*) →* void
+  return (core::String* bar) → void => self::_extension#0|foo(#this, bar);
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/issue44844.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue44844.dart.weak.modular.expect
new file mode 100644
index 0000000..1a705d7
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue44844.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/issue44844.dart:7:8: Error: 'foo' is already declared in this scope.
+//   void foo() {}
+//        ^^^
+// pkg/front_end/testcases/extensions/issue44844.dart:6:14: Context: Previous declaration of 'foo'.
+//   static int foo = 2;
+//              ^^^
+//
+// pkg/front_end/testcases/extensions/issue44844.dart:11:5: Error: The method 'foo' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+//   3.foo();
+//     ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+extension _extension#0 on core::int* {
+  static field foo = self::_extension#0|foo;
+}
+static field core::int* _extension#0|foo;
+static method test() → void {
+  invalid-expression "pkg/front_end/testcases/extensions/issue44844.dart:11:5: Error: The method 'foo' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+  3.foo();
+    ^^^" in 3{<unresolved>}.foo();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/issue47345.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/issue47345.dart.weak.modular.expect
new file mode 100644
index 0000000..38d9756
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/issue47345.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → self::Foo
+    : super core::Object::•()
+    ;
+}
+extension _extension#0 on self::Foo {
+  static field bar = self::_extension#0|bar;
+  static field doubleBar = self::_extension#0|doubleBar;
+}
+static const field core::int _extension#0|bar = #C1;
+static const field core::int _extension#0|doubleBar = #C2;
+static method main() → void {}
+
+constants  {
+  #C1 = 1
+  #C2 = 2
+}
diff --git a/pkg/front_end/testcases/extensions/language_issue1182.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/language_issue1182.dart.weak.modular.expect
new file mode 100644
index 0000000..d952a83
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/language_issue1182.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/language_issue1182.dart:13:25: Error: A value of type 'num Function(num)' can't be assigned to a variable of type 'S Function(S)'.
+//     S Function(S) f = x.test;
+//                         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo<S extends core::num*> extends core::Object {
+  synthetic constructor •() → self::Foo<self::Foo::S*>*
+    : super core::Object::•()
+    ;
+  method test1(covariant-by-class self::Foo::S* x) → void {
+    (self::Foo::S*) →* self::Foo::S* f = invalid-expression "pkg/front_end/testcases/extensions/language_issue1182.dart:13:25: Error: A value of type 'num Function(num)' can't be assigned to a variable of type 'S Function(S)'.
+    S Function(S) f = x.test;
+                        ^" in self::Test|get#test<core::num*>(x) as{TypeError} Never;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Test<T extends core::Object* = dynamic> on T* {
+  get test = self::Test|get#test;
+}
+static method Test|get#test<T extends core::Object* = dynamic>(lowered final self::Test|get#test::T* #this) → (self::Test|get#test::T*) →* self::Test|get#test::T*
+  return (self::Test|get#test::T* a) → self::Test|get#test::T* => #this;
+static method main() → void {}
diff --git a/pkg/front_end/testcases/extensions/missing_toplevel.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/missing_toplevel.dart.weak.modular.expect
new file mode 100644
index 0000000..6d6179a
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/missing_toplevel.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/missing_toplevel.dart:13:23: Error: The getter 'setter' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/extensions/missing_toplevel.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'setter'.
+// var missingGetter = c.setter += 42;
+//                       ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+  set setter = self::Extension|set#setter;
+}
+static field self::Class* c = new self::Class::•();
+static field dynamic missingGetter = let final self::Class* #t1 = self::c in let final dynamic #t2 = invalid-expression "pkg/front_end/testcases/extensions/missing_toplevel.dart:13:23: Error: The getter 'setter' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/extensions/missing_toplevel.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'setter'.
+var missingGetter = c.setter += 42;
+                      ^^^^^^" in #t1{<unresolved>}.setter{dynamic}.+(42) as{TypeError,ForDynamic} core::int* in let final void #t3 = self::Extension|set#setter(#t1, #t2) in #t2;
+static method Extension|set#setter(lowered final self::Class* #this, core::int* value) → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/multi_export.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/multi_export.dart.weak.modular.expect
new file mode 100644
index 0000000..b369c9b
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/multi_export.dart.weak.modular.expect
@@ -0,0 +1,98 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "multi_export_lib1.dart" as mul;
+import "multi_export_lib.dart" as mul2;
+import "multi_export_lib2.dart" as mul3;
+import "multi_export_lib3.dart" as mul4;
+import "multi_export_lib4.dart" as mul5;
+
+import "org-dartlang-testcase:///multi_export_lib1.dart" as lib;
+import "org-dartlang-testcase:///multi_export_lib2.dart" as lib;
+import "org-dartlang-testcase:///multi_export_lib3.dart" as lib;
+import "org-dartlang-testcase:///multi_export_lib4.dart" as lib;
+
+static method main() → dynamic {
+  let final mul::SubClass1 #t1 = new mul::SubClass1::•() in block {
+    mul2::Extension|method<mul::SubClass1>(#t1);
+  } =>#t1;
+  let final mul3::SubClass2 #t2 = new mul3::SubClass2::•() in block {
+    mul2::Extension|method<mul3::SubClass2>(#t2);
+  } =>#t2;
+  let final mul4::SubClass3 #t3 = new mul4::SubClass3::•() in block {
+    mul2::Extension|method<mul4::SubClass3>(#t3);
+  } =>#t3;
+  let final mul5::SubClass4 #t4 = new mul5::SubClass4::•() in block {
+    mul2::Extension|method<mul5::SubClass4>(#t4);
+  } =>#t4;
+}
+
+library /*isNonNullableByDefault*/;
+import self as mul;
+import "multi_export_lib.dart" as mul2;
+
+import "org-dartlang-testcase:///multi_export_lib.dart";
+
+class SubClass1 extends mul2::Class {
+  synthetic constructor •() → mul::SubClass1
+    : super mul2::Class::•()
+    ;
+}
+
+library /*isNonNullableByDefault*/;
+import self as mul3;
+import "multi_export_lib.dart" as mul2;
+additionalExports = (mul2::Extension)
+
+import "org-dartlang-testcase:///multi_export_lib.dart";
+export "org-dartlang-testcase:///multi_export_lib.dart" show Extension;
+
+class SubClass2 extends mul2::Class {
+  synthetic constructor •() → mul3::SubClass2
+    : super mul2::Class::•()
+    ;
+}
+
+library /*isNonNullableByDefault*/;
+import self as mul4;
+import "multi_export_lib.dart" as mul2;
+additionalExports = (mul2::Extension)
+
+import "org-dartlang-testcase:///multi_export_lib.dart";
+export "org-dartlang-testcase:///multi_export_lib.dart" show Extension;
+
+class SubClass3 extends mul2::Class {
+  synthetic constructor •() → mul4::SubClass3
+    : super mul2::Class::•()
+    ;
+}
+
+library /*isNonNullableByDefault*/;
+import self as mul5;
+import "multi_export_lib.dart" as mul2;
+additionalExports = (mul2::Extension)
+
+import "org-dartlang-testcase:///multi_export_lib.dart";
+export "org-dartlang-testcase:///multi_export_lib.dart" show Extension;
+
+class SubClass4 extends mul2::Class {
+  synthetic constructor •() → mul5::SubClass4
+    : super mul2::Class::•()
+    ;
+}
+
+library /*isNonNullableByDefault*/;
+import self as mul2;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → mul2::Class
+    : super core::Object::•()
+    ;
+}
+extension Extension<T extends mul2::Class> on T {
+  method method = mul2::Extension|method;
+  tearoff method = mul2::Extension|get#method;
+}
+static method Extension|method<T extends mul2::Class>(lowered final mul2::Extension|method::T #this) → dynamic {}
+static method Extension|get#method<T extends mul2::Class>(lowered final mul2::Extension|get#method::T #this) → () → dynamic
+  return () → dynamic => mul2::Extension|method<mul2::Extension|get#method::T>(#this);
diff --git a/pkg/front_end/testcases/extensions/nested_on_types.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/nested_on_types.dart.weak.modular.expect
new file mode 100644
index 0000000..001a0b6
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/nested_on_types.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension<T extends core::Object* = dynamic> on self::A<self::A<T*>*>* {
+  method method1 = self::Extension|method1;
+  tearoff method1 = self::Extension|get#method1;
+  method method2 = self::Extension|method2;
+  tearoff method2 = self::Extension|get#method2;
+}
+static method Extension|method1<T extends core::Object* = dynamic>(lowered final self::A<self::A<self::Extension|method1::T*>*>* #this) → dynamic {}
+static method Extension|get#method1<T extends core::Object* = dynamic>(lowered final self::A<self::A<self::Extension|get#method1::T*>*>* #this) → () →* dynamic
+  return () → dynamic => self::Extension|method1<self::Extension|get#method1::T*>(#this);
+static method Extension|method2<T extends core::Object* = dynamic, A extends core::Object* = dynamic>(lowered final self::A<self::A<self::Extension|method2::T*>*>* #this, self::Extension|method2::A* a) → dynamic {}
+static method Extension|get#method2<T extends core::Object* = dynamic>(lowered final self::A<self::A<self::Extension|get#method2::T*>*>* #this) → <A extends core::Object* = dynamic>(A*) →* dynamic
+  return <A extends core::Object* = dynamic>(A* a) → dynamic => self::Extension|method2<self::Extension|get#method2::T*, A*>(#this, a);
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/null_aware.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/null_aware.dart.weak.modular.expect
new file mode 100644
index 0000000..31cc462
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/null_aware.dart.weak.modular.expect
@@ -0,0 +1,87 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int* field = null;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+  get property = self::Extension|get#property;
+  method method = self::Extension|method;
+  tearoff method = self::Extension|get#method;
+  method testImplicitThis = self::Extension|testImplicitThis;
+  tearoff testImplicitThis = self::Extension|get#testImplicitThis;
+  set property = self::Extension|set#property;
+}
+static method Extension|get#property(lowered final self::Class* #this) → core::int*
+  return #this.{self::Class::field}{core::int*};
+static method Extension|set#property(lowered final self::Class* #this, core::int* value) → void {
+  #this.{self::Class::field} = value;
+}
+static method Extension|method(lowered final self::Class* #this) → core::int*
+  return #this.{self::Class::field}{core::int*};
+static method Extension|get#method(lowered final self::Class* #this) → () →* core::int*
+  return () → core::int* => self::Extension|method(#this);
+static method Extension|testImplicitThis(lowered final self::Class* #this) → dynamic {
+  self::expect(null, self::Extension|get#property(#this));
+  self::expect(42, let final core::int* #t1 = self::Extension|get#property(#this) in #t1 == null ?{core::int*} let final core::int* #t2 = 42 in let final void #t3 = self::Extension|set#property(#this, #t2) in #t2 : #t1);
+  self::expect(42, let final core::int* #t4 = self::Extension|get#property(#this) in #t4 == null ?{core::int*} let final core::int* #t5 = 87 in let final void #t6 = self::Extension|set#property(#this, #t5) in #t5 : #t4);
+}
+static method Extension|get#testImplicitThis(lowered final self::Class* #this) → () →* dynamic
+  return () → dynamic => self::Extension|testImplicitThis(#this);
+static method main() → dynamic {
+  self::Class* c;
+  self::expect(null, let final self::Class* #t7 = c in #t7 == null ?{core::int*} null : self::Extension|get#property(#t7));
+  self::expect(null, let final self::Class* #t8 = c in #t8 == null ?{() →* core::int*} null : self::Extension|get#method(#t8));
+  self::expect(null, let final self::Class* #t9 = c in #t9 == null ?{core::int*} null : self::Extension|method(#t9));
+  self::expect(null, let final self::Class* #t10 = c in #t10 == null ?{core::int*} null : let final core::int* #t11 = 42 in let final void #t12 = self::Extension|set#property(#t10, #t11) in #t11);
+  self::expect(null, let final self::Class* #t13 = c in #t13 == null ?{core::int*} null : let final core::int* #t14 = self::Extension|get#property(#t13) in #t14 == null ?{core::int*} let final core::int* #t15 = 42 in let final void #t16 = self::Extension|set#property(#t13, #t15) in #t15 : #t14);
+  c = new self::Class::•();
+  self::expect(null, let final self::Class* #t17 = c in #t17 == null ?{core::int*} null : self::Extension|get#property(#t17));
+  self::expect(null, let final self::Class* #t18 = c in #t18 == null ?{core::int*} null : self::Extension|method(#t18));
+  () →* core::int* tearOff = let final self::Class* #t19 = c in #t19 == null ?{() →* core::int*} null : self::Extension|get#method(#t19);
+  self::expect(null, tearOff(){() →* core::int*});
+  self::expect(42, let final self::Class* #t20 = c in #t20 == null ?{core::int*} null : let final core::int* #t21 = 42 in let final void #t22 = self::Extension|set#property(#t20, #t21) in #t21);
+  self::expect(42, tearOff(){() →* core::int*});
+  self::expect(null, let final self::Class* #t23 = c in #t23 == null ?{Null} null : let final Null #t24 = null in let final void #t25 = self::Extension|set#property(#t23, #t24) in #t24);
+  self::expect(42, let final self::Class* #t26 = c in #t26 == null ?{core::int*} null : let final core::int* #t27 = 42 in let final void #t28 = self::Extension|set#property(#t26, #t27) in #t27);
+  let final self::Class* #t29 = c in #t29 == null ?{Null} null : self::Extension|set#property(#t29, null);
+  self::expect(null, let final self::Class* #t30 = c in #t30 == null ?{core::int*} null : self::Extension|get#property(#t30));
+  self::expect(42, let final self::Class* #t31 = c in let final core::int* #t32 = self::Extension|get#property(#t31) in #t32 == null ?{core::int*} let final core::int* #t33 = 42 in let final void #t34 = self::Extension|set#property(#t31, #t33) in #t33 : #t32);
+  self::expect(42, let final self::Class* #t35 = c in let final core::int* #t36 = self::Extension|get#property(#t35) in #t36 == null ?{core::int*} let final core::int* #t37 = 87 in let final void #t38 = self::Extension|set#property(#t35, #t37) in #t37 : #t36);
+  self::expect(null, let final self::Class* #t39 = c in #t39 == null ?{Null} null : let final Null #t40 = null in let final void #t41 = self::Extension|set#property(#t39, #t40) in #t40);
+  let final self::Class* #t42 = c in self::Extension|get#property(#t42) == null ?{core::int*} self::Extension|set#property(#t42, 42) : null;
+  self::expect(42, let final self::Class* #t43 = c in #t43 == null ?{core::int*} null : self::Extension|get#property(#t43));
+  let final self::Class* #t44 = c in self::Extension|get#property(#t44) == null ?{core::int*} self::Extension|set#property(#t44, 87) : null;
+  self::expect(42, let final self::Class* #t45 = c in #t45 == null ?{core::int*} null : self::Extension|get#property(#t45));
+  let final self::Class* #t46 = c in #t46 == null ?{Null} null : self::Extension|set#property(#t46, null);
+  self::expect(null, let final self::Class* #t47 = c in #t47 == null ?{core::int*} null : self::Extension|get#property(#t47));
+  self::expect(42, let final self::Class* #t48 = c in let final core::int* #t49 = self::Extension|get#property(#t48) in #t49 == null ?{core::int*} let final core::int* #t50 = 42 in let final void #t51 = self::Extension|set#property(#t48, #t50) in #t50 : #t49);
+  self::expect(42, let final self::Class* #t52 = c in let final core::int* #t53 = self::Extension|get#property(#t52) in #t53 == null ?{core::int*} let final core::int* #t54 = 87 in let final void #t55 = self::Extension|set#property(#t52, #t54) in #t54 : #t53);
+  let final self::Class* #t56 = c in #t56 == null ?{Null} null : self::Extension|set#property(#t56, null);
+  self::expect(null, let final self::Class* #t57 = c in #t57 == null ?{core::int*} null : self::Extension|get#property(#t57));
+  let final self::Class* #t58 = c in self::Extension|get#property(#t58) == null ?{core::int*} self::Extension|set#property(#t58, 42) : null;
+  self::expect(42, let final self::Class* #t59 = c in #t59 == null ?{core::int*} null : self::Extension|get#property(#t59));
+  let final self::Class* #t60 = c in self::Extension|get#property(#t60) == null ?{core::int*} self::Extension|set#property(#t60, 87) : null;
+  self::expect(42, let final self::Class* #t61 = c in #t61 == null ?{core::int*} null : self::Extension|get#property(#t61));
+  let final self::Class* #t62 = c in #t62 == null ?{Null} null : self::Extension|set#property(#t62, null);
+  self::Extension|testImplicitThis(c);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/on_function_type.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/on_function_type.dart.weak.modular.expect
new file mode 100644
index 0000000..7fd4a5b
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/on_function_type.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class<T extends self::Class<self::Class::T*>* = self::Class<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Subclass extends self::Class<self::Subclass*> {
+  synthetic constructor •() → self::Subclass*
+    : super self::Class::•()
+    ;
+}
+extension _extension#0<R extends core::Object* = dynamic, T extends core::Object* = dynamic> on (T*) →* R* {
+  get returnType = self::_extension#0|get#returnType;
+  get parameterType = self::_extension#0|get#parameterType;
+}
+extension _extension#1<T extends self::Class<T*>* = self::Class<dynamic>*> on <S extends T* = dynamic>(T*, S*) →* dynamic {
+  get parameterType = self::_extension#1|get#parameterType;
+}
+static method _extension#0|get#returnType<R extends core::Object* = dynamic, T extends core::Object* = dynamic>(lowered final (self::_extension#0|get#returnType::T*) →* self::_extension#0|get#returnType::R* #this) → core::Type*
+  return self::_extension#0|get#returnType::R*;
+static method _extension#0|get#parameterType<R extends core::Object* = dynamic, T extends core::Object* = dynamic>(lowered final (self::_extension#0|get#parameterType::T*) →* self::_extension#0|get#parameterType::R* #this) → core::Type*
+  return self::_extension#0|get#parameterType::T*;
+static method _extension#1|get#parameterType<T extends self::Class<self::_extension#1|get#parameterType::T*>* = self::Class<dynamic>*>(lowered final <S extends self::_extension#1|get#parameterType::T* = dynamic>(self::_extension#1|get#parameterType::T*, S*) →* dynamic #this) → core::Type*
+  return self::_extension#1|get#parameterType::T*;
+static method main() → dynamic {
+  function local1(core::int* i) → core::int*
+    return i;
+  core::print(self::_extension#0|get#returnType<core::int*, core::int*>(local1));
+  core::print(self::_extension#0|get#parameterType<core::int*, core::int*>(local1));
+  function local2<S extends self::Subclass*>(self::Subclass* a, S* b) → self::Subclass*
+    return a;
+  core::print(self::_extension#1|get#parameterType<self::Subclass*>(local2));
+}
diff --git a/pkg/front_end/testcases/extensions/on_type_inference.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/on_type_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..a5fc214
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/on_type_inference.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+extension BestCom<T extends core::num*> on core::Iterable<T*>* {
+  method best = self::BestCom|best;
+  tearoff best = self::BestCom|get#best;
+}
+extension BestList<T extends core::Object* = dynamic> on core::List<T*>* {
+  method best = self::BestList|best;
+  tearoff best = self::BestList|get#best;
+}
+extension BestSpec on core::List<core::num*>* {
+  method best = self::BestSpec|best;
+  tearoff best = self::BestSpec|get#best;
+}
+static method BestCom|best<T extends core::num*>(lowered final core::Iterable<self::BestCom|best::T*>* #this) → self::BestCom|best::T*
+  return null;
+static method BestCom|get#best<T extends core::num*>(lowered final core::Iterable<self::BestCom|get#best::T*>* #this) → () →* self::BestCom|get#best::T*
+  return () → self::BestCom|get#best::T* => self::BestCom|best<self::BestCom|get#best::T*>(#this);
+static method BestList|best<T extends core::Object* = dynamic>(lowered final core::List<self::BestList|best::T*>* #this) → self::BestList|best::T*
+  return null;
+static method BestList|get#best<T extends core::Object* = dynamic>(lowered final core::List<self::BestList|get#best::T*>* #this) → () →* self::BestList|get#best::T*
+  return () → self::BestList|get#best::T* => self::BestList|best<self::BestList|get#best::T*>(#this);
+static method BestSpec|best(lowered final core::List<core::num*>* #this) → core::num*
+  return null;
+static method BestSpec|get#best(lowered final core::List<core::num*>* #this) → () →* core::num*
+  return () → core::num* => self::BestSpec|best(#this);
+static method main() → dynamic {
+  core::List<core::int*>* x;
+  core::int* v = self::BestList|best<core::int*>(x);
+  core::List<core::num*>* y;
+  core::num* w = self::BestSpec|best(y);
+}
diff --git a/pkg/front_end/testcases/extensions/on_type_variable_inference.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/on_type_variable_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..ea9e928
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/on_type_variable_inference.dart.weak.modular.expect
@@ -0,0 +1,148 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/on_type_variable_inference.dart:44:13: Error: The method 'method' isn't defined for the class 'NonStruct'.
+//  - 'NonStruct' is from 'pkg/front_end/testcases/extensions/on_type_variable_inference.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'method'.
+//   nonStruct.method();
+//             ^^^^^^
+//
+// pkg/front_end/testcases/extensions/on_type_variable_inference.dart:45:34: Error: The getter 'property' isn't defined for the class 'NonStruct'.
+//  - 'NonStruct' is from 'pkg/front_end/testcases/extensions/on_type_variable_inference.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'property'.
+//   nonStruct.property = nonStruct.property;
+//                                  ^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/on_type_variable_inference.dart:45:13: Error: The setter 'property' isn't defined for the class 'NonStruct'.
+//  - 'NonStruct' is from 'pkg/front_end/testcases/extensions/on_type_variable_inference.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'property'.
+//   nonStruct.property = nonStruct.property;
+//             ^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/on_type_variable_inference.dart:46:19: Error: The method 'method' isn't defined for the class 'NonStruct'.
+//  - 'NonStruct' is from 'pkg/front_end/testcases/extensions/on_type_variable_inference.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'method'.
+//   new NonStruct().method();
+//                   ^^^^^^
+//
+// pkg/front_end/testcases/extensions/on_type_variable_inference.dart:47:19: Error: The getter 'property' isn't defined for the class 'NonStruct'.
+//  - 'NonStruct' is from 'pkg/front_end/testcases/extensions/on_type_variable_inference.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'property'.
+//   new NonStruct().property;
+//                   ^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/on_type_variable_inference.dart:48:19: Error: The setter 'property' isn't defined for the class 'NonStruct'.
+//  - 'NonStruct' is from 'pkg/front_end/testcases/extensions/on_type_variable_inference.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'property'.
+//   new NonStruct().property = null;
+//                   ^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Struct extends core::Object {
+  synthetic constructor •() → self::Struct*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class StructA extends self::Struct {
+  synthetic constructor •() → self::StructA*
+    : super self::Struct::•()
+    ;
+}
+class StructB extends self::Struct {
+  synthetic constructor •() → self::StructB*
+    : super self::Struct::•()
+    ;
+}
+class NonStruct extends core::Object {
+  synthetic constructor •() → self::NonStruct*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension<T extends self::Struct*> on T* {
+  method method = self::Extension|method;
+  tearoff method = self::Extension|get#method;
+  get property = self::Extension|get#property;
+  set property = self::Extension|set#property;
+}
+static method Extension|method<T extends self::Struct*>(lowered final self::Extension|method::T* #this) → self::Extension|method::T*
+  return #this;
+static method Extension|get#method<T extends self::Struct*>(lowered final self::Extension|get#method::T* #this) → () →* self::Extension|get#method::T*
+  return () → self::Extension|get#method::T* => self::Extension|method<self::Extension|get#method::T*>(#this);
+static method Extension|get#property<T extends self::Struct*>(lowered final self::Extension|get#property::T* #this) → self::Extension|get#property::T*
+  return #this;
+static method Extension|set#property<T extends self::Struct*>(lowered final self::Extension|set#property::T* #this, self::Extension|set#property::T* value) → void {}
+static method main() → dynamic {
+  self::Struct* struct;
+  self::StructA* structA;
+  self::StructB* structB;
+  self::Extension|method<self::Struct*>(struct);
+  self::Extension|set#property<self::Struct*>(struct, self::Extension|get#property<self::StructA*>(structA));
+  self::Extension|method<self::StructA*>(structA);
+  self::Extension|set#property<self::StructA*>(structA, self::Extension|get#property<self::Struct*>(struct) as{TypeError} self::StructA*);
+  self::Extension|method<self::StructB*>(structB);
+  self::Extension|set#property<self::StructB*>(structB, self::Extension|get#property<self::StructB*>(structB));
+  self::Extension|method<self::Struct*>(new self::Struct::•());
+  self::Extension|get#property<self::Struct*>(new self::Struct::•());
+  self::Extension|set#property<self::Struct*>(new self::Struct::•(), null);
+  self::Extension|method<self::StructA*>(new self::StructA::•());
+  self::Extension|get#property<self::StructA*>(new self::StructA::•());
+  self::Extension|set#property<self::StructA*>(new self::StructA::•(), null);
+  self::Extension|method<self::StructB*>(new self::StructB::•());
+  self::Extension|get#property<self::StructB*>(new self::StructB::•());
+  self::Extension|set#property<self::StructB*>(new self::StructB::•(), null);
+}
+static method testNonStruct() → dynamic {
+  self::NonStruct* nonStruct;
+  invalid-expression "pkg/front_end/testcases/extensions/on_type_variable_inference.dart:44:13: Error: The method 'method' isn't defined for the class 'NonStruct'.
+ - 'NonStruct' is from 'pkg/front_end/testcases/extensions/on_type_variable_inference.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'method'.
+  nonStruct.method();
+            ^^^^^^" in nonStruct{<unresolved>}.method();
+  invalid-expression "pkg/front_end/testcases/extensions/on_type_variable_inference.dart:45:13: Error: The setter 'property' isn't defined for the class 'NonStruct'.
+ - 'NonStruct' is from 'pkg/front_end/testcases/extensions/on_type_variable_inference.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'property'.
+  nonStruct.property = nonStruct.property;
+            ^^^^^^^^" in nonStruct{<unresolved>}.property = invalid-expression "pkg/front_end/testcases/extensions/on_type_variable_inference.dart:45:34: Error: The getter 'property' isn't defined for the class 'NonStruct'.
+ - 'NonStruct' is from 'pkg/front_end/testcases/extensions/on_type_variable_inference.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'property'.
+  nonStruct.property = nonStruct.property;
+                                 ^^^^^^^^" in nonStruct{<unresolved>}.property;
+  invalid-expression "pkg/front_end/testcases/extensions/on_type_variable_inference.dart:46:19: Error: The method 'method' isn't defined for the class 'NonStruct'.
+ - 'NonStruct' is from 'pkg/front_end/testcases/extensions/on_type_variable_inference.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'method'.
+  new NonStruct().method();
+                  ^^^^^^" in new self::NonStruct::•(){<unresolved>}.method();
+  invalid-expression "pkg/front_end/testcases/extensions/on_type_variable_inference.dart:47:19: Error: The getter 'property' isn't defined for the class 'NonStruct'.
+ - 'NonStruct' is from 'pkg/front_end/testcases/extensions/on_type_variable_inference.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'property'.
+  new NonStruct().property;
+                  ^^^^^^^^" in new self::NonStruct::•(){<unresolved>}.property;
+  invalid-expression "pkg/front_end/testcases/extensions/on_type_variable_inference.dart:48:19: Error: The setter 'property' isn't defined for the class 'NonStruct'.
+ - 'NonStruct' is from 'pkg/front_end/testcases/extensions/on_type_variable_inference.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'property'.
+  new NonStruct().property = null;
+                  ^^^^^^^^" in new self::NonStruct::•(){<unresolved>}.property = null;
+}
diff --git a/pkg/front_end/testcases/extensions/operators.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/operators.dart.weak.modular.expect
new file mode 100644
index 0000000..d97d9f4
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/operators.dart.weak.modular.expect
@@ -0,0 +1,147 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/operators.dart:125:3: Error: Explicit extension application cannot be used as an expression.
+//   Operators(c) == c;
+//   ^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/operators.dart:126:3: Error: Explicit extension application cannot be used as an expression.
+//   Operators(c) != c;
+//   ^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Complex extends core::Object /*hasConstConstructor*/  {
+  final field core::double* real;
+  final field core::double* imaginary;
+  const constructor •(core::double* real, core::double* imaginary) → self::Complex*
+    : self::Complex::real = real, self::Complex::imaginary = imaginary, super core::Object::•()
+    ;
+  method add(self::Complex* other) → self::Complex* {
+    return new self::Complex::•(this.{self::Complex::real}{core::double*}.{core::double::+}(other.{self::Complex::real}{core::double*}){(core::num*) →* core::double*}, this.{self::Complex::imaginary}{core::double*}.{core::double::+}(other.{self::Complex::imaginary}{core::double*}){(core::num*) →* core::double*});
+  }
+  method sub(self::Complex* other) → self::Complex* {
+    return new self::Complex::•(this.{self::Complex::real}{core::double*}.{core::double::-}(other.{self::Complex::real}{core::double*}){(core::num*) →* core::double*}, this.{self::Complex::imaginary}{core::double*}.{core::double::-}(other.{self::Complex::imaginary}{core::double*}){(core::num*) →* core::double*});
+  }
+  method negate() → self::Complex* {
+    return new self::Complex::•(this.{self::Complex::real}{core::double*}.{core::double::unary-}(){() →* core::double*}, this.{self::Complex::imaginary}{core::double*}.{core::double::unary-}(){() →* core::double*});
+  }
+  get hashCode() → core::int*
+    return this.{self::Complex::real}{core::double*}.{core::num::hashCode}{core::int*}.{core::num::*}(13){(core::num*) →* core::int*}.{core::num::+}(this.{self::Complex::imaginary}{core::double*}.{core::num::hashCode}{core::int*}.{core::num::*}(19){(core::num*) →* core::int*}){(core::num*) →* core::int*};
+  operator ==(core::Object* other) → core::bool* {
+    if(core::identical(this, other))
+      return true;
+    return other is self::Complex* && this.{self::Complex::real}{core::double*} =={core::num::==}{(core::Object*) →* core::bool*} other{self::Complex*}.{self::Complex::real}{core::double*} && this.{self::Complex::imaginary}{core::double*} =={core::num::==}{(core::Object*) →* core::bool*} other{self::Complex*}.{self::Complex::imaginary}{core::double*};
+  }
+  method toString() → core::String*
+    return "Complex(${this.{self::Complex::real}{core::double*}},${this.{self::Complex::imaginary}{core::double*}})";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Operators on self::Complex* {
+  operator + = self::Operators|+;
+  operator - = self::Operators|-;
+  operator unary- = self::Operators|unary-;
+}
+static method Operators|+(lowered final self::Complex* #this, self::Complex* other) → self::Complex*
+  return #this.{self::Complex::add}(other){(self::Complex*) →* self::Complex*};
+static method Operators|-(lowered final self::Complex* #this, self::Complex* other) → self::Complex*
+  return #this.{self::Complex::sub}(other){(self::Complex*) →* self::Complex*};
+static method Operators|unary-(lowered final self::Complex* #this) → self::Complex*
+  return #this.{self::Complex::negate}(){() →* self::Complex*};
+static method main() → dynamic {
+  self::implicit();
+  self::explicit();
+}
+static method implicit() → dynamic {
+  self::Complex* c_m2 = new self::Complex::•(-2.0, 2.0);
+  self::Complex* c_m1 = new self::Complex::•(-1.0, 1.0);
+  self::Complex* c0 = new self::Complex::•(0.0, 0.0);
+  self::Complex* c1 = new self::Complex::•(1.0, -1.0);
+  self::Complex* c2 = new self::Complex::•(2.0, -2.0);
+  self::expect(c_m2, self::Operators|+(c0, c_m2));
+  self::expect(c_m2, self::Operators|+(c_m2, c0));
+  self::expect(c_m2, self::Operators|+(c_m1, c_m1));
+  self::expect(c_m1, self::Operators|+(c0, c_m1));
+  self::expect(c_m1, self::Operators|+(c_m1, c0));
+  self::expect(c0, self::Operators|+(c_m2, c2));
+  self::expect(c0, self::Operators|+(c2, c_m2));
+  self::expect(c0, self::Operators|+(c_m1, c1));
+  self::expect(c0, self::Operators|+(c1, c_m1));
+  self::expect(c0, self::Operators|+(c0, c0));
+  self::expect(c1, self::Operators|+(c0, c1));
+  self::expect(c1, self::Operators|+(c1, c0));
+  self::expect(c2, self::Operators|+(c0, c2));
+  self::expect(c2, self::Operators|+(c2, c0));
+  self::expect(c2, self::Operators|+(c1, c1));
+  self::expect(c_m2, self::Operators|-(c0, c2));
+  self::expect(c2, self::Operators|-(c2, c0));
+  self::expect(c_m2, self::Operators|unary-(c2));
+  self::expect(c_m1, self::Operators|-(c1, c2));
+  self::expect(c1, self::Operators|-(c2, c1));
+  self::expect(c_m1, self::Operators|-(c0, c1));
+  self::expect(c1, self::Operators|-(c1, c0));
+  self::expect(c_m1, self::Operators|unary-(c1));
+  self::expect(c0, self::Operators|-(c2, c2));
+  self::expect(c0, self::Operators|-(c1, c1));
+  self::expect(c0, self::Operators|-(c0, c0));
+  self::expect(c0, self::Operators|-(c_m1, c_m1));
+  self::expect(c0, self::Operators|-(c_m2, c_m2));
+  self::expect(c0, self::Operators|unary-(c0));
+}
+static method explicit() → dynamic {
+  self::Complex* c_m2 = new self::Complex::•(-2.0, 2.0);
+  self::Complex* c_m1 = new self::Complex::•(-1.0, 1.0);
+  self::Complex* c0 = new self::Complex::•(0.0, 0.0);
+  self::Complex* c1 = new self::Complex::•(1.0, -1.0);
+  self::Complex* c2 = new self::Complex::•(2.0, -2.0);
+  self::expect(c_m2, self::Operators|+(c0, c_m2));
+  self::expect(c_m2, self::Operators|+(c_m2, c0));
+  self::expect(c_m2, self::Operators|+(c_m1, c_m1));
+  self::expect(c_m1, self::Operators|+(c0, c_m1));
+  self::expect(c_m1, self::Operators|+(c_m1, c0));
+  self::expect(c0, self::Operators|+(c_m2, c2));
+  self::expect(c0, self::Operators|+(c2, c_m2));
+  self::expect(c0, self::Operators|+(c_m1, c1));
+  self::expect(c0, self::Operators|+(c1, c_m1));
+  self::expect(c0, self::Operators|+(c0, c0));
+  self::expect(c1, self::Operators|+(c0, c1));
+  self::expect(c1, self::Operators|+(c1, c0));
+  self::expect(c2, self::Operators|+(c0, c2));
+  self::expect(c2, self::Operators|+(c2, c0));
+  self::expect(c2, self::Operators|+(c1, c1));
+  self::expect(c_m2, self::Operators|-(c0, c2));
+  self::expect(c2, self::Operators|-(c2, c0));
+  self::expect(c_m2, self::Operators|unary-(c2));
+  self::expect(c_m1, self::Operators|-(c1, c2));
+  self::expect(c1, self::Operators|-(c2, c1));
+  self::expect(c_m1, self::Operators|-(c0, c1));
+  self::expect(c1, self::Operators|-(c1, c0));
+  self::expect(c_m1, self::Operators|unary-(c1));
+  self::expect(c0, self::Operators|-(c2, c2));
+  self::expect(c0, self::Operators|-(c1, c1));
+  self::expect(c0, self::Operators|-(c0, c0));
+  self::expect(c0, self::Operators|-(c_m1, c_m1));
+  self::expect(c0, self::Operators|-(c_m2, c_m2));
+  self::expect(c0, self::Operators|unary-(c0));
+}
+static method errors(self::Complex* c) → void {
+  invalid-expression "pkg/front_end/testcases/extensions/operators.dart:125:3: Error: Explicit extension application cannot be used as an expression.
+  Operators(c) == c;
+  ^^^^^^^^^" =={core::Object::==}{(core::Object*) →* core::bool*} c;
+  !(invalid-expression "pkg/front_end/testcases/extensions/operators.dart:126:3: Error: Explicit extension application cannot be used as an expression.
+  Operators(c) != c;
+  ^^^^^^^^^" =={core::Object::==}{(core::Object*) →* core::bool*} c);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/other_kinds.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/other_kinds.dart.weak.modular.expect
new file mode 100644
index 0000000..5a567f7
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/other_kinds.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  field core::int* _instanceField = null;
+  static field core::int* _staticField = 0;
+  synthetic constructor •() → self::A1*
+    : super core::Object::•()
+    ;
+  method getInstanceField() → core::int*
+    return this.{self::A1::_instanceField}{core::int*};
+  method setInstanceField(core::int* value) → void {
+    this.{self::A1::_instanceField} = value;
+  }
+  static method getStaticField() → core::int*
+    return self::A1::_staticField;
+  static method setStaticField(core::int* value) → void {
+    self::A1::_staticField = value;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension A2 on self::A1* {
+  get instanceProperty = self::A2|get#instanceProperty;
+  operator + = self::A2|+;
+  operator - = self::A2|-;
+  operator unary- = self::A2|unary-;
+  static field staticField = self::A2|staticField;
+  static get staticProperty = get self::A2|staticProperty;
+  set instanceProperty = self::A2|set#instanceProperty;
+  static set staticProperty = set self::A2|staticProperty;
+}
+static field core::int* A2|staticField = self::A1::getStaticField();
+static method A2|get#instanceProperty(lowered final self::A1* #this) → core::int*
+  return #this.{self::A1::getInstanceField}(){() →* core::int*};
+static method A2|set#instanceProperty(lowered final self::A1* #this, core::int* value) → void {
+  #this.{self::A1::setInstanceField}(value){(core::int*) →* void};
+}
+static method A2|+(lowered final self::A1* #this, core::int* value) → core::int* {
+  return #this.{self::A1::getInstanceField}(){() →* core::int*}.{core::num::+}(value){(core::num*) →* core::int*};
+}
+static method A2|-(lowered final self::A1* #this, core::int* value) → core::int* {
+  return #this.{self::A1::getInstanceField}(){() →* core::int*}.{core::num::-}(value){(core::num*) →* core::int*};
+}
+static method A2|unary-(lowered final self::A1* #this) → core::int* {
+  return #this.{self::A1::getInstanceField}(){() →* core::int*}.{core::int::unary-}(){() →* core::int*};
+}
+static get A2|staticProperty() → core::int*
+  return self::A1::getStaticField();
+static set A2|staticProperty(core::int* value) → void {
+  self::A1::setStaticField(value);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/private_members.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/private_members.dart.weak.modular.expect
new file mode 100644
index 0000000..1e4a440
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/private_members.dart.weak.modular.expect
@@ -0,0 +1,223 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/private_members.dart:23:14: Error: Method not found: '_PrivateExtension'.
+//   expect(42, _PrivateExtension("").publicMethod1());
+//              ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/private_members.dart:24:14: Error: Method not found: '_PrivateExtension'.
+//   expect(87, _PrivateExtension("")._privateMethod1());
+//              ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/private_members.dart:25:35: Error: Method not found: '_privateMethod2'.
+//   expect(237, PublicExtension("")._privateMethod2());
+//                                   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/private_members.dart:27:14: Error: Undefined name '_PrivateExtension'.
+//   expect(24, _PrivateExtension.publicStaticMethod1());
+//              ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/private_members.dart:28:14: Error: Undefined name '_PrivateExtension'.
+//   expect(78, _PrivateExtension._privateStaticMethod1());
+//              ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/private_members.dart:29:31: Error: Member not found: 'PublicExtension._privateStaticMethod2'.
+//   expect(732, PublicExtension._privateStaticMethod2());
+//                               ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/private_members.dart:17:17: Error: The method 'publicMethod1' isn't defined for the class 'String'.
+// Try correcting the name to the name of an existing method, or defining a method named 'publicMethod1'.
+//   expect(42, "".publicMethod1());
+//                 ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/private_members.dart:18:17: Error: The method '_privateMethod1' isn't defined for the class 'String'.
+// Try correcting the name to the name of an existing method, or defining a method named '_privateMethod1'.
+//   expect(87, ""._privateMethod1());
+//                 ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/private_members.dart:19:18: Error: The method '_privateMethod2' isn't defined for the class 'String'.
+// Try correcting the name to the name of an existing method, or defining a method named '_privateMethod2'.
+//   expect(237, ""._privateMethod2());
+//                  ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/private_members.dart:20:18: Error: The method 'publicMethod3' isn't defined for the class 'String'.
+// Try correcting the name to the name of an existing method, or defining a method named 'publicMethod3'.
+//   expect(473, "".publicMethod3());
+//                  ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/private_members.dart:21:18: Error: The method '_privateMethod3' isn't defined for the class 'String'.
+// Try correcting the name to the name of an existing method, or defining a method named '_privateMethod3'.
+//   expect(586, ""._privateMethod3());
+//                  ^^^^^^^^^^^^^^^
+//
+import self as self;
+import "private_members_lib.dart" as pri;
+
+import "org-dartlang-testcase:///private_members_lib.dart";
+
+static method main() → dynamic {
+  pri::test();
+  pri::expect(123, pri::PublicExtension|publicMethod2(""));
+  pri::expect(123, pri::PublicExtension|publicMethod2(""));
+  pri::expect(321, pri::PublicExtension|publicStaticMethod2());
+}
+static method errors() → dynamic {
+  pri::expect(42, invalid-expression "pkg/front_end/testcases/extensions/private_members.dart:17:17: Error: The method 'publicMethod1' isn't defined for the class 'String'.
+Try correcting the name to the name of an existing method, or defining a method named 'publicMethod1'.
+  expect(42, \"\".publicMethod1());
+                ^^^^^^^^^^^^^" in ""{<unresolved>}.publicMethod1());
+  pri::expect(87, invalid-expression "pkg/front_end/testcases/extensions/private_members.dart:18:17: Error: The method '_privateMethod1' isn't defined for the class 'String'.
+Try correcting the name to the name of an existing method, or defining a method named '_privateMethod1'.
+  expect(87, \"\"._privateMethod1());
+                ^^^^^^^^^^^^^^^" in ""{<unresolved>}._privateMethod1());
+  pri::expect(237, invalid-expression "pkg/front_end/testcases/extensions/private_members.dart:19:18: Error: The method '_privateMethod2' isn't defined for the class 'String'.
+Try correcting the name to the name of an existing method, or defining a method named '_privateMethod2'.
+  expect(237, \"\"._privateMethod2());
+                 ^^^^^^^^^^^^^^^" in ""{<unresolved>}._privateMethod2());
+  pri::expect(473, invalid-expression "pkg/front_end/testcases/extensions/private_members.dart:20:18: Error: The method 'publicMethod3' isn't defined for the class 'String'.
+Try correcting the name to the name of an existing method, or defining a method named 'publicMethod3'.
+  expect(473, \"\".publicMethod3());
+                 ^^^^^^^^^^^^^" in ""{<unresolved>}.publicMethod3());
+  pri::expect(586, invalid-expression "pkg/front_end/testcases/extensions/private_members.dart:21:18: Error: The method '_privateMethod3' isn't defined for the class 'String'.
+Try correcting the name to the name of an existing method, or defining a method named '_privateMethod3'.
+  expect(586, \"\"._privateMethod3());
+                 ^^^^^^^^^^^^^^^" in ""{<unresolved>}._privateMethod3());
+  pri::expect(42, invalid-expression "pkg/front_end/testcases/extensions/private_members.dart:23:14: Error: Method not found: '_PrivateExtension'.
+  expect(42, _PrivateExtension(\"\").publicMethod1());
+             ^^^^^^^^^^^^^^^^^"{dynamic}.publicMethod1());
+  pri::expect(87, invalid-expression "pkg/front_end/testcases/extensions/private_members.dart:24:14: Error: Method not found: '_PrivateExtension'.
+  expect(87, _PrivateExtension(\"\")._privateMethod1());
+             ^^^^^^^^^^^^^^^^^"{dynamic}._privateMethod1());
+  pri::expect(237, invalid-expression "pkg/front_end/testcases/extensions/private_members.dart:25:35: Error: Method not found: '_privateMethod2'.
+  expect(237, PublicExtension(\"\")._privateMethod2());
+                                  ^^^^^^^^^^^^^^^");
+  pri::expect(24, invalid-expression "pkg/front_end/testcases/extensions/private_members.dart:27:14: Error: Undefined name '_PrivateExtension'.
+  expect(24, _PrivateExtension.publicStaticMethod1());
+             ^^^^^^^^^^^^^^^^^"{dynamic}.publicStaticMethod1());
+  pri::expect(78, invalid-expression "pkg/front_end/testcases/extensions/private_members.dart:28:14: Error: Undefined name '_PrivateExtension'.
+  expect(78, _PrivateExtension._privateStaticMethod1());
+             ^^^^^^^^^^^^^^^^^"{dynamic}._privateStaticMethod1());
+  pri::expect(732, invalid-expression "pkg/front_end/testcases/extensions/private_members.dart:29:31: Error: Member not found: 'PublicExtension._privateStaticMethod2'.
+  expect(732, PublicExtension._privateStaticMethod2());
+                              ^^^^^^^^^^^^^^^^^^^^^");
+}
+
+library;
+import self as pri;
+import "dart:core" as core;
+
+extension _PrivateExtension on core::String* {
+  method publicMethod1 = pri::_PrivateExtension|publicMethod1;
+  tearoff publicMethod1 = pri::_PrivateExtension|get#publicMethod1;
+  method _privateMethod1 = pri::_PrivateExtension|_privateMethod1;
+  tearoff _privateMethod1 = pri::_PrivateExtension|get#_privateMethod1;
+  static method publicStaticMethod1 = pri::_PrivateExtension|publicStaticMethod1;
+  static method _privateStaticMethod1 = pri::_PrivateExtension|_privateStaticMethod1;
+  method test1 = pri::_PrivateExtension|test1;
+  tearoff test1 = pri::_PrivateExtension|get#test1;
+}
+extension PublicExtension on core::String* {
+  method publicMethod2 = pri::PublicExtension|publicMethod2;
+  tearoff publicMethod2 = pri::PublicExtension|get#publicMethod2;
+  method _privateMethod2 = pri::PublicExtension|_privateMethod2;
+  tearoff _privateMethod2 = pri::PublicExtension|get#_privateMethod2;
+  static method publicStaticMethod2 = pri::PublicExtension|publicStaticMethod2;
+  static method _privateStaticMethod2 = pri::PublicExtension|_privateStaticMethod2;
+  method test2 = pri::PublicExtension|test2;
+  tearoff test2 = pri::PublicExtension|get#test2;
+}
+extension _extension#0 on core::String* {
+  method publicMethod3 = pri::_extension#0|publicMethod3;
+  tearoff publicMethod3 = pri::_extension#0|get#publicMethod3;
+  method _privateMethod3 = pri::_extension#0|_privateMethod3;
+  tearoff _privateMethod3 = pri::_extension#0|get#_privateMethod3;
+  static method publicStaticMethod3 = pri::_extension#0|publicStaticMethod3;
+  static method _privateStaticMethod3 = pri::_extension#0|_privateStaticMethod3;
+  method test3 = pri::_extension#0|test3;
+  tearoff test3 = pri::_extension#0|get#test3;
+}
+static method _PrivateExtension|publicMethod1(lowered final core::String* #this) → core::int*
+  return 42;
+static method _PrivateExtension|get#publicMethod1(lowered final core::String* #this) → () →* core::int*
+  return () → core::int* => pri::_PrivateExtension|publicMethod1(#this);
+static method _PrivateExtension|_privateMethod1(lowered final core::String* #this) → core::int*
+  return 87;
+static method _PrivateExtension|get#_privateMethod1(lowered final core::String* #this) → () →* core::int*
+  return () → core::int* => pri::_PrivateExtension|_privateMethod1(#this);
+static method _PrivateExtension|publicStaticMethod1() → core::int*
+  return 24;
+static method _PrivateExtension|_privateStaticMethod1() → core::int*
+  return 78;
+static method _PrivateExtension|test1(lowered final core::String* #this) → dynamic {
+  pri::expect(42, pri::_PrivateExtension|publicMethod1(#this));
+  pri::expect(87, pri::_PrivateExtension|_privateMethod1(#this));
+  pri::expect(24, pri::_PrivateExtension|publicStaticMethod1());
+  pri::expect(78, pri::_PrivateExtension|_privateStaticMethod1());
+}
+static method _PrivateExtension|get#test1(lowered final core::String* #this) → () →* dynamic
+  return () → dynamic => pri::_PrivateExtension|test1(#this);
+static method PublicExtension|publicMethod2(lowered final core::String* #this) → core::int*
+  return 123;
+static method PublicExtension|get#publicMethod2(lowered final core::String* #this) → () →* core::int*
+  return () → core::int* => pri::PublicExtension|publicMethod2(#this);
+static method PublicExtension|_privateMethod2(lowered final core::String* #this) → core::int*
+  return 237;
+static method PublicExtension|get#_privateMethod2(lowered final core::String* #this) → () →* core::int*
+  return () → core::int* => pri::PublicExtension|_privateMethod2(#this);
+static method PublicExtension|publicStaticMethod2() → core::int*
+  return 321;
+static method PublicExtension|_privateStaticMethod2() → core::int*
+  return 732;
+static method PublicExtension|test2(lowered final core::String* #this) → dynamic {
+  pri::expect(123, pri::PublicExtension|publicMethod2(#this));
+  pri::expect(237, pri::PublicExtension|_privateMethod2(#this));
+  pri::expect(321, pri::PublicExtension|publicStaticMethod2());
+  pri::expect(732, pri::PublicExtension|_privateStaticMethod2());
+}
+static method PublicExtension|get#test2(lowered final core::String* #this) → () →* dynamic
+  return () → dynamic => pri::PublicExtension|test2(#this);
+static method _extension#0|publicMethod3(lowered final core::String* #this) → core::int*
+  return 473;
+static method _extension#0|get#publicMethod3(lowered final core::String* #this) → () →* core::int*
+  return () → core::int* => pri::_extension#0|publicMethod3(#this);
+static method _extension#0|_privateMethod3(lowered final core::String* #this) → core::int*
+  return 586;
+static method _extension#0|get#_privateMethod3(lowered final core::String* #this) → () →* core::int*
+  return () → core::int* => pri::_extension#0|_privateMethod3(#this);
+static method _extension#0|publicStaticMethod3() → core::int*
+  return 374;
+static method _extension#0|_privateStaticMethod3() → core::int*
+  return 685;
+static method _extension#0|test3(lowered final core::String* #this) → dynamic {
+  pri::expect(473, pri::_extension#0|publicMethod3(#this));
+  pri::expect(586, pri::_extension#0|_privateMethod3(#this));
+  pri::expect(374, pri::_extension#0|publicStaticMethod3());
+  pri::expect(685, pri::_extension#0|_privateStaticMethod3());
+}
+static method _extension#0|get#test3(lowered final core::String* #this) → () →* dynamic
+  return () → dynamic => pri::_extension#0|test3(#this);
+static method test() → dynamic {
+  pri::expect(42, pri::_PrivateExtension|publicMethod1(""));
+  pri::expect(87, pri::_PrivateExtension|_privateMethod1(""));
+  pri::expect(123, pri::PublicExtension|publicMethod2(""));
+  pri::expect(237, pri::PublicExtension|_privateMethod2(""));
+  pri::expect(473, pri::_extension#0|publicMethod3(""));
+  pri::expect(586, pri::_extension#0|_privateMethod3(""));
+  pri::expect(42, pri::_PrivateExtension|publicMethod1(""));
+  pri::expect(87, pri::_PrivateExtension|_privateMethod1(""));
+  pri::expect(123, pri::PublicExtension|publicMethod2(""));
+  pri::expect(237, pri::PublicExtension|_privateMethod2(""));
+  pri::expect(24, pri::_PrivateExtension|publicStaticMethod1());
+  pri::expect(78, pri::_PrivateExtension|_privateStaticMethod1());
+  pri::expect(321, pri::PublicExtension|publicStaticMethod2());
+  pri::expect(732, pri::PublicExtension|_privateStaticMethod2());
+  pri::_PrivateExtension|test1("");
+  pri::PublicExtension|test2("");
+  pri::_extension#0|test3("");
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/static_access.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/static_access.dart.weak.modular.expect
new file mode 100644
index 0000000..973805f
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/static_access.dart.weak.modular.expect
@@ -0,0 +1,58 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+  static method method = self::Extension|method;
+  static method genericMethod = self::Extension|genericMethod;
+  static get property = get self::Extension|property;
+  static field field = self::Extension|field;
+  method instanceMethod = self::Extension|instanceMethod;
+  tearoff instanceMethod = self::Extension|get#instanceMethod;
+  get instanceProperty = self::Extension|get#instanceProperty;
+  static set property = set self::Extension|property;
+  set instanceProperty = self::Extension|set#instanceProperty;
+}
+static field dynamic Extension|field;
+static method Extension|method() → dynamic {}
+static method Extension|genericMethod<T extends core::Object* = dynamic>(self::Extension|genericMethod::T* t) → dynamic {}
+static get Extension|property() → dynamic
+  return 42;
+static set Extension|property(dynamic value) → void {}
+static method Extension|instanceMethod(lowered final self::Class* #this) → dynamic {}
+static method Extension|get#instanceMethod(lowered final self::Class* #this) → () →* dynamic
+  return () → dynamic => self::Extension|instanceMethod(#this);
+static method Extension|get#instanceProperty(lowered final self::Class* #this) → dynamic
+  return 42;
+static method Extension|set#instanceProperty(lowered final self::Class* #this, dynamic value) → void {}
+static method main() → dynamic {
+  self::Extension|method();
+  self::Extension|genericMethod<core::int*>(42);
+  self::Extension|genericMethod<core::num*>(42);
+  #C1;
+  #C2;
+  self::Extension|property;
+  self::Extension|property = 42;
+  self::Extension|field;
+  self::Extension|field = 42;
+}
+
+constants  {
+  #C1 = static-tearoff self::Extension|method
+  #C2 = static-tearoff self::Extension|genericMethod
+}
diff --git a/pkg/front_end/testcases/extensions/static_access_of_instance.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/static_access_of_instance.dart.weak.modular.expect
new file mode 100644
index 0000000..b6e0e94
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/static_access_of_instance.dart.weak.modular.expect
@@ -0,0 +1,64 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/static_access_of_instance.dart:14:13: Error: Member not found: 'Extension.instanceMethod'.
+//   Extension.instanceMethod();
+//             ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/static_access_of_instance.dart:15:13: Error: Member not found: 'instanceMethod'.
+//   Extension.instanceMethod;
+//             ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/static_access_of_instance.dart:16:13: Error: Member not found: 'instanceProperty'.
+//   Extension.instanceProperty;
+//             ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/extensions/static_access_of_instance.dart:17:13: Error: Setter not found: 'instanceProperty'.
+//   Extension.instanceProperty = 42;
+//             ^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+  method instanceMethod = self::Extension|instanceMethod;
+  tearoff instanceMethod = self::Extension|get#instanceMethod;
+  get instanceProperty = self::Extension|get#instanceProperty;
+  set instanceProperty = self::Extension|set#instanceProperty;
+}
+static method Extension|instanceMethod(lowered final self::Class* #this) → dynamic {}
+static method Extension|get#instanceMethod(lowered final self::Class* #this) → () →* dynamic
+  return () → dynamic => self::Extension|instanceMethod(#this);
+static method Extension|get#instanceProperty(lowered final self::Class* #this) → dynamic
+  return 42;
+static method Extension|set#instanceProperty(lowered final self::Class* #this, dynamic value) → void {}
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/extensions/static_access_of_instance.dart:14:13: Error: Member not found: 'Extension.instanceMethod'.
+  Extension.instanceMethod();
+            ^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/static_access_of_instance.dart:15:13: Error: Member not found: 'instanceMethod'.
+  Extension.instanceMethod;
+            ^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/static_access_of_instance.dart:16:13: Error: Member not found: 'instanceProperty'.
+  Extension.instanceProperty;
+            ^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/extensions/static_access_of_instance.dart:17:13: Error: Setter not found: 'instanceProperty'.
+  Extension.instanceProperty = 42;
+            ^^^^^^^^^^^^^^^^";
+}
diff --git a/pkg/front_end/testcases/extensions/tear_offs.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/tear_offs.dart.weak.modular.expect
new file mode 100644
index 0000000..d56bc4b
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/tear_offs.dart.weak.modular.expect
@@ -0,0 +1,75 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/extensions/tear_offs.dart:17:31: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'int Function(int)'.
+//     int Function(int) intId = getter;
+//                               ^
+//
+// pkg/front_end/testcases/extensions/tear_offs.dart:30:31: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'num Function(num)'.
+//   num Function(num) numId = c.getter;
+//                               ^
+//
+// pkg/front_end/testcases/extensions/tear_offs.dart:31:45: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'bool Function(bool)'.
+//   bool Function(bool) boolId = Extension(c).getter;
+//                                             ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+  method id = self::Extension|id;
+  tearoff id = self::Extension|get#id;
+  get getter = self::Extension|get#getter;
+  method method = self::Extension|method;
+  tearoff method = self::Extension|get#method;
+  method errors = self::Extension|errors;
+  tearoff errors = self::Extension|get#errors;
+}
+static method Extension|id<T extends core::Object* = dynamic>(lowered final self::Class* #this, self::Extension|id::T* t) → self::Extension|id::T*
+  return t;
+static method Extension|get#id(lowered final self::Class* #this) → <T extends core::Object* = dynamic>(T*) →* T*
+  return <T extends core::Object* = dynamic>(T* t) → T* => self::Extension|id<T*>(#this, t);
+static method Extension|get#getter(lowered final self::Class* #this) → <T extends core::Object* = dynamic>(T*) →* T*
+  return self::Extension|get#id(#this);
+static method Extension|method(lowered final self::Class* #this) → dynamic {
+  (core::String*) →* core::String* stringId = self::Extension|get#id(#this)<core::String*>;
+}
+static method Extension|get#method(lowered final self::Class* #this) → () →* dynamic
+  return () → dynamic => self::Extension|method(#this);
+static method Extension|errors(lowered final self::Class* #this) → dynamic {
+  (core::int*) →* core::int* intId = invalid-expression "pkg/front_end/testcases/extensions/tear_offs.dart:17:31: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'int Function(int)'.
+    int Function(int) intId = getter;
+                              ^" in self::Extension|get#getter(#this) as{TypeError} (core::int*) →* core::int*;
+}
+static method Extension|get#errors(lowered final self::Class* #this) → () →* dynamic
+  return () → dynamic => self::Extension|errors(#this);
+static method main() → dynamic {
+  self::Class* c = new self::Class::•();
+  (core::int*) →* core::int* intId = self::Extension|get#id(c)<core::int*>;
+  (core::double*) →* core::double* doubleId = self::Extension|get#id(c)<core::double*>;
+}
+static method errors() → dynamic {
+  self::Class* c = new self::Class::•();
+  (core::num*) →* core::num* numId = invalid-expression "pkg/front_end/testcases/extensions/tear_offs.dart:30:31: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'num Function(num)'.
+  num Function(num) numId = c.getter;
+                              ^" in self::Extension|get#getter(c) as{TypeError} (core::num*) →* core::num*;
+  (core::bool*) →* core::bool* boolId = invalid-expression "pkg/front_end/testcases/extensions/tear_offs.dart:31:45: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'bool Function(bool)'.
+  bool Function(bool) boolId = Extension(c).getter;
+                                            ^" in self::Extension|get#getter(c) as{TypeError} (core::bool*) →* core::bool*;
+}
diff --git a/pkg/front_end/testcases/extensions/type_variable_bound.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/type_variable_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..42e4b34
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/type_variable_bound.dart.weak.modular.expect
@@ -0,0 +1,61 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class SubClass extends self::Class {
+  synthetic constructor •() → self::SubClass*
+    : super self::Class::•()
+    ;
+}
+extension Extension<T extends core::Object* = dynamic> on T* {
+  method method1 = self::Extension|method1;
+  tearoff method1 = self::Extension|get#method1;
+}
+extension BoundExtension<T extends self::Class*> on T* {
+  method method2 = self::BoundExtension|method2;
+  tearoff method2 = self::BoundExtension|get#method2;
+}
+static method Extension|method1<T extends core::Object* = dynamic>(lowered final self::Extension|method1::T* #this) → self::Extension|method1::T*
+  return #this;
+static method Extension|get#method1<T extends core::Object* = dynamic>(lowered final self::Extension|get#method1::T* #this) → () →* self::Extension|get#method1::T*
+  return () → self::Extension|get#method1::T* => self::Extension|method1<self::Extension|get#method1::T*>(#this);
+static method BoundExtension|method2<T extends self::Class*>(lowered final self::BoundExtension|method2::T* #this) → self::BoundExtension|method2::T*
+  return #this;
+static method BoundExtension|get#method2<T extends self::Class*>(lowered final self::BoundExtension|get#method2::T* #this) → () →* self::BoundExtension|get#method2::T*
+  return () → self::BoundExtension|get#method2::T* => self::BoundExtension|method2<self::BoundExtension|get#method2::T*>(#this);
+static method test1<T extends core::Object* = dynamic>(self::test1::T* t1) → self::Class* {
+  if(t1 is self::SubClass*) {
+    return self::Extension|method1<self::SubClass*>(t1{self::test1::T* & self::SubClass* /* '*' & '*' = '*' */});
+  }
+  return new self::Class::•();
+}
+static method test2<T extends self::Class*>(self::test2::T* t2) → dynamic {
+  if(self::test2::T* =={core::Type::==}{(core::Object*) →* core::bool*} #C1) {
+    self::SubClass* subClass = self::BoundExtension|method2<self::Class*>(t2) as{TypeError} self::SubClass*;
+  }
+}
+static method test3<T extends core::Object* = dynamic>(self::test3::T* t3) → dynamic {
+  if(t3 is self::SubClass*) {
+    self::SubClass* subClass = self::BoundExtension|method2<self::SubClass*>(t3{self::test3::T* & self::SubClass* /* '*' & '*' = '*' */});
+  }
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = TypeLiteralConstant(self::SubClass*)
+}
diff --git a/pkg/front_end/testcases/extensions/type_variables.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/type_variables.dart.weak.modular.expect
new file mode 100644
index 0000000..aeae0f7
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/type_variables.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A1<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A1<self::A1::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension A2<T extends core::Object* = dynamic> on self::A1<T*>* {
+  method method1 = self::A2|method1;
+  tearoff method1 = self::A2|get#method1;
+  method method2 = self::A2|method2;
+  tearoff method2 = self::A2|get#method2;
+}
+extension A3<T extends self::A1<T*>* = self::A1<dynamic>*> on self::A1<T*>* {
+}
+extension A4<T extends core::Object* = dynamic> on self::A1<T*>* {
+  method method = self::A4|method;
+  tearoff method = self::A4|get#method;
+}
+static method A2|method1<T extends core::Object* = dynamic, S extends self::A2|method1::T* = dynamic>(lowered final self::A1<self::A2|method1::T*>* #this) → self::A1<self::A2|method1::T*>* {
+  return #this;
+}
+static method A2|get#method1<T extends core::Object* = dynamic>(lowered final self::A1<self::A2|get#method1::T*>* #this) → <S extends self::A2|get#method1::T* = dynamic>() →* self::A1<self::A2|get#method1::T*>*
+  return <S extends self::A2|get#method1::T* = dynamic>() → self::A1<self::A2|get#method1::T*>* => self::A2|method1<self::A2|get#method1::T*, S*>(#this);
+static method A2|method2<T extends core::Object* = dynamic, S extends self::A1<self::A2|method2::T*>* = self::A1<dynamic>*>(lowered final self::A1<self::A2|method2::T*>* #this, self::A2|method2::S* o) → self::A1<self::A2|method2::T*>* {
+  core::print(o);
+  core::print(self::A2|method2::T*);
+  core::print(self::A2|method2::S*);
+  return #this;
+}
+static method A2|get#method2<T extends core::Object* = dynamic>(lowered final self::A1<self::A2|get#method2::T*>* #this) → <S extends self::A1<self::A2|get#method2::T*>* = self::A1<dynamic>*>(S*) →* self::A1<self::A2|get#method2::T*>*
+  return <S extends self::A1<self::A2|get#method2::T*>* = self::A1<dynamic>*>(S* o) → self::A1<self::A2|get#method2::T*>* => self::A2|method2<self::A2|get#method2::T*, S*>(#this, o);
+static method A4|method<#T extends core::Object* = dynamic, T extends core::Object* = dynamic>(lowered final self::A1<self::A4|method::#T*>* #this) → dynamic {}
+static method A4|get#method<#T extends core::Object* = dynamic>(lowered final self::A1<self::A4|get#method::#T*>* #this) → <T extends core::Object* = dynamic>() →* dynamic
+  return <T extends core::Object* = dynamic>() → dynamic => self::A4|method<self::A4|get#method::#T*, T*>(#this);
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/extensions/unnamed_extensions.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/unnamed_extensions.dart.weak.modular.expect
new file mode 100644
index 0000000..6532400
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/unnamed_extensions.dart.weak.modular.expect
@@ -0,0 +1,147 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  field core::int* field;
+  constructor •(core::int* field) → self::Class1*
+    : self::Class1::field = field, super core::Object::•()
+    ;
+  method toString() → core::String*
+    return "Class1(${this.{self::Class1::field}{core::int*}})";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class2 extends core::Object {
+  field core::int* field;
+  constructor •(core::int* field) → self::Class2*
+    : self::Class2::field = field, super core::Object::•()
+    ;
+  method toString() → core::String*
+    return "Class2(${this.{self::Class2::field}{core::int*}})";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension _extension#0 on self::Class1* {
+  method method = self::_extension#0|method;
+  tearoff method = self::_extension#0|get#method;
+  method genericMethod = self::_extension#0|genericMethod;
+  tearoff genericMethod = self::_extension#0|get#genericMethod;
+  get property = self::_extension#0|get#property;
+  set property = self::_extension#0|set#property;
+}
+extension _extension#1 on self::Class2* {
+  method method = self::_extension#1|method;
+  tearoff method = self::_extension#1|get#method;
+  method genericMethod = self::_extension#1|genericMethod;
+  tearoff genericMethod = self::_extension#1|get#genericMethod;
+  get property = self::_extension#1|get#property;
+  set property = self::_extension#1|set#property;
+}
+static method _extension#0|method(lowered final self::Class1* #this) → core::int* {
+  core::print("Extension1.method on ${#this}");
+  return #this.{self::Class1::field}{core::int*};
+}
+static method _extension#0|get#method(lowered final self::Class1* #this) → () →* core::int*
+  return () → core::int* => self::_extension#0|method(#this);
+static method _extension#0|genericMethod<T extends core::num*>(lowered final self::Class1* #this, self::_extension#0|genericMethod::T* t) → core::int* {
+  core::print("Extension1.genericMethod<${self::_extension#0|genericMethod::T*}>(${t}) on ${#this}");
+  return #this.{self::Class1::field}{core::int*}.{core::num::+}(t){(core::num*) →* core::num*} as{TypeError} core::int*;
+}
+static method _extension#0|get#genericMethod(lowered final self::Class1* #this) → <T extends core::num*>(T*) →* core::int*
+  return <T extends core::num*>(T* t) → core::int* => self::_extension#0|genericMethod<T*>(#this, t);
+static method _extension#0|get#property(lowered final self::Class1* #this) → core::int* {
+  core::print("Extension1.property get on ${#this}");
+  return #this.{self::Class1::field}{core::int*};
+}
+static method _extension#0|set#property(lowered final self::Class1* #this, core::int* value) → void {
+  #this.{self::Class1::field} = value;
+  core::print("Extension1.property set(${value}) on ${#this}");
+  value = value.{core::num::+}(1){(core::num*) →* core::int*};
+}
+static method _extension#1|method(lowered final self::Class2* #this) → core::int* {
+  core::print("Extension2.method on ${#this}");
+  return #this.{self::Class2::field}{core::int*}.{core::num::+}(3){(core::num*) →* core::int*};
+}
+static method _extension#1|get#method(lowered final self::Class2* #this) → () →* core::int*
+  return () → core::int* => self::_extension#1|method(#this);
+static method _extension#1|genericMethod<T extends core::num*>(lowered final self::Class2* #this, self::_extension#1|genericMethod::T* t) → core::int* {
+  core::print("Extension2.genericMethod<${self::_extension#1|genericMethod::T*}>(${t}) on ${#this}");
+  return #this.{self::Class2::field}{core::int*}.{core::num::+}(t){(core::num*) →* core::num*}.{core::num::+}(4){(core::num*) →* core::num*} as{TypeError} core::int*;
+}
+static method _extension#1|get#genericMethod(lowered final self::Class2* #this) → <T extends core::num*>(T*) →* core::int*
+  return <T extends core::num*>(T* t) → core::int* => self::_extension#1|genericMethod<T*>(#this, t);
+static method _extension#1|get#property(lowered final self::Class2* #this) → core::int* {
+  core::print("Extension2.property get on ${#this}");
+  return #this.{self::Class2::field}{core::int*}.{core::num::+}(5){(core::num*) →* core::int*};
+}
+static method _extension#1|set#property(lowered final self::Class2* #this, core::int* value) → void {
+  core::print("Extension2.property set(${value}) on ${#this}");
+  value = value.{core::num::+}(1){(core::num*) →* core::int*};
+  #this.{self::Class2::field} = value;
+}
+static method main() → dynamic {
+  self::testExtension1();
+  self::testExtension2();
+}
+static method testExtension1() → dynamic {
+  self::Class1* c0 = new self::Class1::•(0);
+  self::Class1* c1 = new self::Class1::•(1);
+  self::expect(0, self::_extension#0|method(c0));
+  self::expect(1, self::_extension#0|method(c1));
+  self::expect(1, let final self::Class1* #t1 = c1 in #t1 == null ?{core::int*} null : self::_extension#0|method(#t1));
+  self::expect(42, self::_extension#0|genericMethod<core::int*>(c0, 42));
+  self::expect(43, self::_extension#0|genericMethod<core::num*>(c0, 43));
+  self::expect(88, self::_extension#0|genericMethod<core::int*>(c1, 87));
+  self::expect(89, self::_extension#0|genericMethod<core::num*>(c1, 88));
+  self::expect(0, self::_extension#0|get#property(c0));
+  self::expect(0, let final self::Class1* #t2 = c0 in #t2 == null ?{core::int*} null : self::_extension#0|get#property(#t2));
+  self::expect(42, let final core::int* #t3 = 42 in let final void #t4 = self::_extension#0|set#property(c0, #t3) in #t3);
+  self::expect(1, self::_extension#0|get#property(c1));
+  self::expect(87, let final core::int* #t5 = 87 in let final void #t6 = self::_extension#0|set#property(c0, #t5) in #t5);
+  self::expect(27, let final core::int* #t7 = let final core::int* #t8 = 27 in let final void #t9 = self::_extension#0|set#property(c1, #t8) in #t8 in let final void #t10 = self::_extension#0|set#property(c0, #t7) in #t7);
+  self::expect(37, let final core::int* #t11 = let final core::int* #t12 = 37 in let final void #t13 = self::_extension#0|set#property(c0, #t12) in #t12 in let final void #t14 = self::_extension#0|set#property(c1, #t11) in #t11);
+  self::expect(77, let final core::int* #t15 = let final core::int* #t16 = let final core::int* #t17 = 77 in let final void #t18 = self::_extension#0|set#property(c1, #t17) in #t17 in let final void #t19 = self::_extension#0|set#property(c0, #t16) in #t16 in let final void #t20 = self::_extension#0|set#property(c1, #t15) in #t15);
+  self::expect(67, let final core::int* #t21 = let final core::int* #t22 = let final core::int* #t23 = 67 in let final void #t24 = self::_extension#0|set#property(c0, #t23) in #t23 in let final void #t25 = self::_extension#0|set#property(c1, #t22) in #t22 in let final void #t26 = self::_extension#0|set#property(c0, #t21) in #t21);
+}
+static method testExtension2() → dynamic {
+  self::Class2* c0 = new self::Class2::•(0);
+  self::Class2* c1 = new self::Class2::•(1);
+  self::expect(3, self::_extension#1|method(c0));
+  self::expect(3, let final self::Class2* #t27 = c0 in #t27 == null ?{core::int*} null : self::_extension#1|method(#t27));
+  self::expect(4, self::_extension#1|method(c1));
+  self::expect(46, self::_extension#1|genericMethod<core::int*>(c0, 42));
+  self::expect(47, self::_extension#1|genericMethod<core::num*>(c0, 43));
+  self::expect(92, self::_extension#1|genericMethod<core::int*>(c1, 87));
+  self::expect(93, self::_extension#1|genericMethod<core::num*>(c1, 88));
+  self::expect(5, self::_extension#1|get#property(c0));
+  self::expect(5, let final self::Class2* #t28 = c0 in #t28 == null ?{core::int*} null : self::_extension#1|get#property(#t28));
+  self::expect(42, let final core::int* #t29 = 42 in let final void #t30 = self::_extension#1|set#property(c0, #t29) in #t29);
+  self::expect(48, self::_extension#1|get#property(c0));
+  self::expect(6, self::_extension#1|get#property(c1));
+  self::expect(43, let final core::int* #t31 = 43 in let final void #t32 = self::_extension#1|set#property(c1, #t31) in #t31);
+  self::expect(49, self::_extension#1|get#property(c1));
+  self::expect(49, let final core::int* #t33 = self::_extension#1|get#property(c1) in let final void #t34 = self::_extension#1|set#property(c0, #t33) in #t33);
+  self::expect(55, let final core::int* #t35 = self::_extension#1|get#property(c0) in let final void #t36 = self::_extension#1|set#property(c1, #t35) in #t35);
+  self::expect(61, let final core::int* #t37 = let final core::int* #t38 = self::_extension#1|get#property(c1) in let final void #t39 = self::_extension#1|set#property(c0, #t38) in #t38 in let final void #t40 = self::_extension#1|set#property(c1, #t37) in #t37);
+  self::expect(67, let final core::int* #t41 = let final core::int* #t42 = self::_extension#1|get#property(c0) in let final void #t43 = self::_extension#1|set#property(c1, #t42) in #t42 in let final void #t44 = self::_extension#1|set#property(c0, #t41) in #t41);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
diff --git a/pkg/front_end/testcases/extensions/use_this.dart.weak.modular.expect b/pkg/front_end/testcases/extensions/use_this.dart.weak.modular.expect
new file mode 100644
index 0000000..f7ce7a4
--- /dev/null
+++ b/pkg/front_end/testcases/extensions/use_this.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  synthetic constructor •() → self::A1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B1<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B1<self::B1::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension A2 on self::A1* {
+  method method1 = self::A2|method1;
+  tearoff method1 = self::A2|get#method1;
+  method method2 = self::A2|method2;
+  tearoff method2 = self::A2|get#method2;
+}
+extension B2<T extends core::Object* = dynamic> on self::B1<T*>* {
+  method method1 = self::B2|method1;
+  tearoff method1 = self::B2|get#method1;
+  method method2 = self::B2|method2;
+  tearoff method2 = self::B2|get#method2;
+}
+static method A2|method1(lowered final self::A1* #this) → self::A1* {
+  return #this;
+}
+static method A2|get#method1(lowered final self::A1* #this) → () →* self::A1*
+  return () → self::A1* => self::A2|method1(#this);
+static method A2|method2<T extends core::Object* = dynamic>(lowered final self::A1* #this, self::A2|method2::T* o) → self::A1* {
+  core::print(o);
+  return #this;
+}
+static method A2|get#method2(lowered final self::A1* #this) → <T extends core::Object* = dynamic>(T*) →* self::A1*
+  return <T extends core::Object* = dynamic>(T* o) → self::A1* => self::A2|method2<T*>(#this, o);
+static method B2|method1<T extends core::Object* = dynamic>(lowered final self::B1<self::B2|method1::T*>* #this) → self::B1<self::B2|method1::T*>* {
+  return #this;
+}
+static method B2|get#method1<T extends core::Object* = dynamic>(lowered final self::B1<self::B2|get#method1::T*>* #this) → () →* self::B1<self::B2|get#method1::T*>*
+  return () → self::B1<self::B2|get#method1::T*>* => self::B2|method1<self::B2|get#method1::T*>(#this);
+static method B2|method2<T extends core::Object* = dynamic, S extends core::Object* = dynamic>(lowered final self::B1<self::B2|method2::T*>* #this, self::B2|method2::S* o) → self::B1<self::B2|method2::T*>* {
+  core::print(o);
+  return #this;
+}
+static method B2|get#method2<T extends core::Object* = dynamic>(lowered final self::B1<self::B2|get#method2::T*>* #this) → <S extends core::Object* = dynamic>(S*) →* self::B1<self::B2|get#method2::T*>*
+  return <S extends core::Object* = dynamic>(S* o) → self::B1<self::B2|get#method2::T*>* => self::B2|method2<self::B2|get#method2::T*, S*>(#this, o);
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/DeltaBlue.dart.weak.modular.expect b/pkg/front_end/testcases/general/DeltaBlue.dart.weak.modular.expect
new file mode 100644
index 0000000..c7ae21e
--- /dev/null
+++ b/pkg/front_end/testcases/general/DeltaBlue.dart.weak.modular.expect
@@ -0,0 +1,541 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class DeltaBlue extends core::Object {
+  synthetic constructor •() → self::DeltaBlue*
+    : super core::Object::•()
+    ;
+  method run() → void {
+    self::chainTest(100);
+    self::projectionTest(100);
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Strength extends core::Object /*hasConstConstructor*/  {
+  final field core::int* value;
+  final field core::String* name;
+  const constructor •(core::int* value, core::String* name) → self::Strength*
+    : self::Strength::value = value, self::Strength::name = name, super core::Object::•()
+    ;
+  method nextWeaker() → self::Strength*
+    return #C19.{core::List::[]}(this.{self::Strength::value}{core::int*}){(core::int*) →* self::Strength*};
+  static method stronger(self::Strength* s1, self::Strength* s2) → core::bool* {
+    return s1.{self::Strength::value}{core::int*}.{core::num::<}(s2.{self::Strength::value}{core::int*}){(core::num*) →* core::bool*};
+  }
+  static method weaker(self::Strength* s1, self::Strength* s2) → core::bool* {
+    return s1.{self::Strength::value}{core::int*}.{core::num::>}(s2.{self::Strength::value}{core::int*}){(core::num*) →* core::bool*};
+  }
+  static method weakest(self::Strength* s1, self::Strength* s2) → self::Strength* {
+    return self::Strength::weaker(s1, s2) ?{self::Strength*} s1 : s2;
+  }
+  static method strongest(self::Strength* s1, self::Strength* s2) → self::Strength* {
+    return self::Strength::stronger(s1, s2) ?{self::Strength*} s1 : s2;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Constraint extends core::Object /*hasConstConstructor*/  {
+  final field self::Strength* strength;
+  const constructor •(self::Strength* strength) → self::Constraint*
+    : self::Constraint::strength = strength, super core::Object::•()
+    ;
+  abstract method isSatisfied() → core::bool*;
+  abstract method markUnsatisfied() → void;
+  abstract method addToGraph() → void;
+  abstract method removeFromGraph() → void;
+  abstract method chooseMethod(core::int* mark) → void;
+  abstract method markInputs(core::int* mark) → void;
+  abstract method inputsKnown(core::int* mark) → core::bool*;
+  abstract method output() → self::Variable*;
+  abstract method execute() → void;
+  abstract method recalculate() → void;
+  method addConstraint() → void {
+    this.{self::Constraint::addToGraph}(){() →* void};
+    self::planner.{self::Planner::incrementalAdd}(this){(self::Constraint*) →* void};
+  }
+  method satisfy(dynamic mark) → self::Constraint* {
+    this.{self::Constraint::chooseMethod}(mark as{TypeError,ForDynamic} core::int*){(core::int*) →* void};
+    if(!this.{self::Constraint::isSatisfied}(){() →* core::bool*}) {
+      if(this.{self::Constraint::strength}{self::Strength*} =={self::Strength::==}{(dynamic) →* core::bool*} #C22) {
+        core::print("Could not satisfy a required constraint!");
+      }
+      return null;
+    }
+    this.{self::Constraint::markInputs}(mark as{TypeError,ForDynamic} core::int*){(core::int*) →* void};
+    self::Variable* out = this.{self::Constraint::output}(){() →* self::Variable*};
+    self::Constraint* overridden = out.{self::Variable::determinedBy}{self::Constraint*};
+    if(!(overridden == null))
+      overridden.{self::Constraint::markUnsatisfied}(){() →* void};
+    out.{self::Variable::determinedBy} = this;
+    if(!self::planner.{self::Planner::addPropagate}(this, mark as{TypeError,ForDynamic} core::int*){(self::Constraint*, core::int*) →* core::bool*})
+      core::print("Cycle encountered");
+    out.{self::Variable::mark} = mark as{TypeError,ForDynamic} core::int*;
+    return overridden;
+  }
+  method destroyConstraint() → void {
+    if(this.{self::Constraint::isSatisfied}(){() →* core::bool*})
+      self::planner.{self::Planner::incrementalRemove}(this){(self::Constraint*) →* void};
+    this.{self::Constraint::removeFromGraph}(){() →* void};
+  }
+  method isInput() → core::bool*
+    return false;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class UnaryConstraint extends self::Constraint {
+  final field self::Variable* myOutput;
+  field core::bool* satisfied = false;
+  constructor •(self::Variable* myOutput, self::Strength* strength) → self::UnaryConstraint*
+    : self::UnaryConstraint::myOutput = myOutput, super self::Constraint::•(strength) {
+    this.{self::Constraint::addConstraint}(){() →* void};
+  }
+  method addToGraph() → void {
+    this.{self::UnaryConstraint::myOutput}{self::Variable*}.{self::Variable::addConstraint}(this){(self::Constraint*) →* void};
+    this.{self::UnaryConstraint::satisfied} = false;
+  }
+  method chooseMethod(core::int* mark) → void {
+    this.{self::UnaryConstraint::satisfied} = !(this.{self::UnaryConstraint::myOutput}{self::Variable*}.{self::Variable::mark}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} mark) && self::Strength::stronger(this.{self::Constraint::strength}{self::Strength*}, this.{self::UnaryConstraint::myOutput}{self::Variable*}.{self::Variable::walkStrength}{self::Strength*});
+  }
+  method isSatisfied() → core::bool*
+    return this.{self::UnaryConstraint::satisfied}{core::bool*};
+  method markInputs(core::int* mark) → void {}
+  method output() → self::Variable*
+    return this.{self::UnaryConstraint::myOutput}{self::Variable*};
+  method recalculate() → void {
+    this.{self::UnaryConstraint::myOutput}{self::Variable*}.{self::Variable::walkStrength} = this.{self::Constraint::strength}{self::Strength*};
+    this.{self::UnaryConstraint::myOutput}{self::Variable*}.{self::Variable::stay} = !this.{self::Constraint::isInput}(){() →* core::bool*};
+    if(this.{self::UnaryConstraint::myOutput}{self::Variable*}.{self::Variable::stay}{core::bool*})
+      this.{self::Constraint::execute}(){() →* void};
+  }
+  method markUnsatisfied() → void {
+    this.{self::UnaryConstraint::satisfied} = false;
+  }
+  method inputsKnown(core::int* mark) → core::bool*
+    return true;
+  method removeFromGraph() → void {
+    if(!(this.{self::UnaryConstraint::myOutput}{self::Variable*} == null))
+      this.{self::UnaryConstraint::myOutput}{self::Variable*}.{self::Variable::removeConstraint}(this){(self::Constraint*) →* void};
+    this.{self::UnaryConstraint::satisfied} = false;
+  }
+}
+class StayConstraint extends self::UnaryConstraint {
+  constructor •(self::Variable* v, self::Strength* str) → self::StayConstraint*
+    : super self::UnaryConstraint::•(v, str)
+    ;
+  method execute() → void {}
+}
+class EditConstraint extends self::UnaryConstraint {
+  constructor •(self::Variable* v, self::Strength* str) → self::EditConstraint*
+    : super self::UnaryConstraint::•(v, str)
+    ;
+  method isInput() → core::bool*
+    return true;
+  method execute() → void {}
+}
+abstract class BinaryConstraint extends self::Constraint {
+  field self::Variable* v1;
+  field self::Variable* v2;
+  field core::int* direction = #C1;
+  constructor •(self::Variable* v1, self::Variable* v2, self::Strength* strength) → self::BinaryConstraint*
+    : self::BinaryConstraint::v1 = v1, self::BinaryConstraint::v2 = v2, super self::Constraint::•(strength) {
+    this.{self::Constraint::addConstraint}(){() →* void};
+  }
+  method chooseMethod(core::int* mark) → void {
+    if(this.{self::BinaryConstraint::v1}{self::Variable*}.{self::Variable::mark}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} mark) {
+      this.{self::BinaryConstraint::direction} = !(this.{self::BinaryConstraint::v2}{self::Variable*}.{self::Variable::mark}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} mark) && self::Strength::stronger(this.{self::Constraint::strength}{self::Strength*}, this.{self::BinaryConstraint::v2}{self::Variable*}.{self::Variable::walkStrength}{self::Strength*}) ?{core::int*} #C4 : #C1;
+    }
+    if(this.{self::BinaryConstraint::v2}{self::Variable*}.{self::Variable::mark}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} mark) {
+      this.{self::BinaryConstraint::direction} = !(this.{self::BinaryConstraint::v1}{self::Variable*}.{self::Variable::mark}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} mark) && self::Strength::stronger(this.{self::Constraint::strength}{self::Strength*}, this.{self::BinaryConstraint::v1}{self::Variable*}.{self::Variable::walkStrength}{self::Strength*}) ?{core::int*} #C20 : #C1;
+    }
+    if(self::Strength::weaker(this.{self::BinaryConstraint::v1}{self::Variable*}.{self::Variable::walkStrength}{self::Strength*}, this.{self::BinaryConstraint::v2}{self::Variable*}.{self::Variable::walkStrength}{self::Strength*})) {
+      this.{self::BinaryConstraint::direction} = self::Strength::stronger(this.{self::Constraint::strength}{self::Strength*}, this.{self::BinaryConstraint::v1}{self::Variable*}.{self::Variable::walkStrength}{self::Strength*}) ?{core::int*} #C20 : #C1;
+    }
+    else {
+      this.{self::BinaryConstraint::direction} = self::Strength::stronger(this.{self::Constraint::strength}{self::Strength*}, this.{self::BinaryConstraint::v2}{self::Variable*}.{self::Variable::walkStrength}{self::Strength*}) ?{core::int*} #C4 : #C20;
+    }
+  }
+  method addToGraph() → void {
+    this.{self::BinaryConstraint::v1}{self::Variable*}.{self::Variable::addConstraint}(this){(self::Constraint*) →* void};
+    this.{self::BinaryConstraint::v2}{self::Variable*}.{self::Variable::addConstraint}(this){(self::Constraint*) →* void};
+    this.{self::BinaryConstraint::direction} = #C1;
+  }
+  method isSatisfied() → core::bool*
+    return !(this.{self::BinaryConstraint::direction}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} #C1);
+  method markInputs(core::int* mark) → void {
+    this.{self::BinaryConstraint::input}(){() →* self::Variable*}.{self::Variable::mark} = mark;
+  }
+  method input() → self::Variable*
+    return this.{self::BinaryConstraint::direction}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} #C4 ?{self::Variable*} this.{self::BinaryConstraint::v1}{self::Variable*} : this.{self::BinaryConstraint::v2}{self::Variable*};
+  method output() → self::Variable*
+    return this.{self::BinaryConstraint::direction}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} #C4 ?{self::Variable*} this.{self::BinaryConstraint::v2}{self::Variable*} : this.{self::BinaryConstraint::v1}{self::Variable*};
+  method recalculate() → void {
+    self::Variable* ihn = this.{self::BinaryConstraint::input}(){() →* self::Variable*};
+    self::Variable* out = this.{self::BinaryConstraint::output}(){() →* self::Variable*};
+    out.{self::Variable::walkStrength} = self::Strength::weakest(this.{self::Constraint::strength}{self::Strength*}, ihn.{self::Variable::walkStrength}{self::Strength*});
+    out.{self::Variable::stay} = ihn.{self::Variable::stay}{core::bool*};
+    if(out.{self::Variable::stay}{core::bool*})
+      this.{self::Constraint::execute}(){() →* void};
+  }
+  method markUnsatisfied() → void {
+    this.{self::BinaryConstraint::direction} = #C1;
+  }
+  method inputsKnown(core::int* mark) → core::bool* {
+    self::Variable* i = this.{self::BinaryConstraint::input}(){() →* self::Variable*};
+    return i.{self::Variable::mark}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} mark || i.{self::Variable::stay}{core::bool*} || i.{self::Variable::determinedBy}{self::Constraint*} == null;
+  }
+  method removeFromGraph() → void {
+    if(!(this.{self::BinaryConstraint::v1}{self::Variable*} == null))
+      this.{self::BinaryConstraint::v1}{self::Variable*}.{self::Variable::removeConstraint}(this){(self::Constraint*) →* void};
+    if(!(this.{self::BinaryConstraint::v2}{self::Variable*} == null))
+      this.{self::BinaryConstraint::v2}{self::Variable*}.{self::Variable::removeConstraint}(this){(self::Constraint*) →* void};
+    this.{self::BinaryConstraint::direction} = #C1;
+  }
+}
+class ScaleConstraint extends self::BinaryConstraint {
+  final field self::Variable* scale;
+  final field self::Variable* offset;
+  constructor •(self::Variable* src, self::Variable* scale, self::Variable* offset, self::Variable* dest, self::Strength* strength) → self::ScaleConstraint*
+    : self::ScaleConstraint::scale = scale, self::ScaleConstraint::offset = offset, super self::BinaryConstraint::•(src, dest, strength)
+    ;
+  method addToGraph() → void {
+    super.{self::BinaryConstraint::addToGraph}();
+    this.{self::ScaleConstraint::scale}{self::Variable*}.{self::Variable::addConstraint}(this){(self::Constraint*) →* void};
+    this.{self::ScaleConstraint::offset}{self::Variable*}.{self::Variable::addConstraint}(this){(self::Constraint*) →* void};
+  }
+  method removeFromGraph() → void {
+    super.{self::BinaryConstraint::removeFromGraph}();
+    if(!(this.{self::ScaleConstraint::scale}{self::Variable*} == null))
+      this.{self::ScaleConstraint::scale}{self::Variable*}.{self::Variable::removeConstraint}(this){(self::Constraint*) →* void};
+    if(!(this.{self::ScaleConstraint::offset}{self::Variable*} == null))
+      this.{self::ScaleConstraint::offset}{self::Variable*}.{self::Variable::removeConstraint}(this){(self::Constraint*) →* void};
+  }
+  method markInputs(core::int* mark) → void {
+    super.{self::BinaryConstraint::markInputs}(mark);
+    this.{self::ScaleConstraint::scale}{self::Variable*}.{self::Variable::mark} = this.{self::ScaleConstraint::offset}{self::Variable*}.{self::Variable::mark} = mark;
+  }
+  method execute() → void {
+    if(this.{self::BinaryConstraint::direction}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} #C4) {
+      this.{self::BinaryConstraint::v2}{self::Variable*}.{self::Variable::value} = this.{self::BinaryConstraint::v1}{self::Variable*}.{self::Variable::value}{core::int*}.{core::num::*}(this.{self::ScaleConstraint::scale}{self::Variable*}.{self::Variable::value}{core::int*}){(core::num*) →* core::int*}.{core::num::+}(this.{self::ScaleConstraint::offset}{self::Variable*}.{self::Variable::value}{core::int*}){(core::num*) →* core::int*};
+    }
+    else {
+      this.{self::BinaryConstraint::v1}{self::Variable*}.{self::Variable::value} = this.{self::BinaryConstraint::v2}{self::Variable*}.{self::Variable::value}{core::int*}.{core::num::-}(this.{self::ScaleConstraint::offset}{self::Variable*}.{self::Variable::value}{core::int*}){(core::num*) →* core::int*}.{core::num::~/}(this.{self::ScaleConstraint::scale}{self::Variable*}.{self::Variable::value}{core::int*}){(core::num*) →* core::int*};
+    }
+  }
+  method recalculate() → void {
+    self::Variable* ihn = this.{self::BinaryConstraint::input}(){() →* self::Variable*};
+    self::Variable* out = this.{self::BinaryConstraint::output}(){() →* self::Variable*};
+    out.{self::Variable::walkStrength} = self::Strength::weakest(this.{self::Constraint::strength}{self::Strength*}, ihn.{self::Variable::walkStrength}{self::Strength*});
+    out.{self::Variable::stay} = ihn.{self::Variable::stay}{core::bool*} && this.{self::ScaleConstraint::scale}{self::Variable*}.{self::Variable::stay}{core::bool*} && this.{self::ScaleConstraint::offset}{self::Variable*}.{self::Variable::stay}{core::bool*};
+    if(out.{self::Variable::stay}{core::bool*})
+      this.{self::ScaleConstraint::execute}(){() →* void};
+  }
+}
+class EqualityConstraint extends self::BinaryConstraint {
+  constructor •(self::Variable* v1, self::Variable* v2, self::Strength* strength) → self::EqualityConstraint*
+    : super self::BinaryConstraint::•(v1, v2, strength)
+    ;
+  method execute() → void {
+    this.{self::BinaryConstraint::output}(){() →* self::Variable*}.{self::Variable::value} = this.{self::BinaryConstraint::input}(){() →* self::Variable*}.{self::Variable::value}{core::int*};
+  }
+}
+class Variable extends core::Object {
+  field core::List<self::Constraint*>* constraints = <self::Constraint*>[];
+  field self::Constraint* determinedBy = null;
+  field core::int* mark = 0;
+  field self::Strength* walkStrength = #C18;
+  field core::bool* stay = true;
+  field core::int* value;
+  final field core::String* name;
+  constructor •(core::String* name, core::int* value) → self::Variable*
+    : self::Variable::name = name, self::Variable::value = value, super core::Object::•()
+    ;
+  method addConstraint(self::Constraint* c) → void {
+    this.{self::Variable::constraints}{core::List<self::Constraint*>*}.{core::List::add}(c){(self::Constraint*) →* void};
+  }
+  method removeConstraint(self::Constraint* c) → void {
+    this.{self::Variable::constraints}{core::List<self::Constraint*>*}.{core::List::remove}(c){(core::Object*) →* core::bool*};
+    if(this.{self::Variable::determinedBy}{self::Constraint*} =={self::Constraint::==}{(dynamic) →* core::bool*} c)
+      this.{self::Variable::determinedBy} = null;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Planner extends core::Object {
+  field core::int* currentMark = 0;
+  synthetic constructor •() → self::Planner*
+    : super core::Object::•()
+    ;
+  method incrementalAdd(self::Constraint* c) → void {
+    core::int* mark = this.{self::Planner::newMark}(){() →* core::int*};
+    for (self::Constraint* overridden = c.{self::Constraint::satisfy}(mark){(dynamic) →* self::Constraint*}; !(overridden == null); overridden = overridden.{self::Constraint::satisfy}(mark){(dynamic) →* self::Constraint*})
+      ;
+  }
+  method incrementalRemove(self::Constraint* c) → void {
+    self::Variable* out = c.{self::Constraint::output}(){() →* self::Variable*};
+    c.{self::Constraint::markUnsatisfied}(){() →* void};
+    c.{self::Constraint::removeFromGraph}(){() →* void};
+    core::List<self::Constraint*>* unsatisfied = this.{self::Planner::removePropagateFrom}(out){(self::Variable*) →* core::List<self::Constraint*>*};
+    self::Strength* strength = #C22;
+    do {
+      for (core::int* i = 0; i.{core::num::<}(unsatisfied.{core::List::length}{core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+        self::Constraint* u = unsatisfied.{core::List::[]}(i){(core::int*) →* self::Constraint*};
+        if(u.{self::Constraint::strength}{self::Strength*} =={self::Strength::==}{(dynamic) →* core::bool*} strength)
+          this.{self::Planner::incrementalAdd}(u){(self::Constraint*) →* void};
+      }
+      strength = strength.{self::Strength::nextWeaker}(){() →* self::Strength*};
+    }
+    while (!(strength =={self::Strength::==}{(dynamic) →* core::bool*} #C18))
+  }
+  method newMark() → core::int*
+    return this.{self::Planner::currentMark} = this.{self::Planner::currentMark}{core::int*}.{core::num::+}(1){(core::num*) →* core::int*};
+  method makePlan(core::List<self::Constraint*>* sources) → self::Plan* {
+    core::int* mark = this.{self::Planner::newMark}(){() →* core::int*};
+    self::Plan* plan = new self::Plan::•();
+    core::List<self::Constraint*>* todo = sources;
+    while (todo.{core::List::length}{core::int*}.{core::num::>}(0){(core::num*) →* core::bool*}) {
+      self::Constraint* c = todo.{core::List::removeLast}(){() →* self::Constraint*};
+      if(!(c.{self::Constraint::output}(){() →* self::Variable*}.{self::Variable::mark}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} mark) && c.{self::Constraint::inputsKnown}(mark){(core::int*) →* core::bool*}) {
+        plan.{self::Plan::addConstraint}(c){(self::Constraint*) →* void};
+        c.{self::Constraint::output}(){() →* self::Variable*}.{self::Variable::mark} = mark;
+        this.{self::Planner::addConstraintsConsumingTo}(c.{self::Constraint::output}(){() →* self::Variable*}, todo){(self::Variable*, core::List<self::Constraint*>*) →* void};
+      }
+    }
+    return plan;
+  }
+  method extractPlanFromConstraints(core::List<self::Constraint*>* constraints) → self::Plan* {
+    core::List<self::Constraint*>* sources = <self::Constraint*>[];
+    for (core::int* i = 0; i.{core::num::<}(constraints.{core::List::length}{core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+      self::Constraint* c = constraints.{core::List::[]}(i){(core::int*) →* self::Constraint*};
+      if(c.{self::Constraint::isInput}(){() →* core::bool*} && c.{self::Constraint::isSatisfied}(){() →* core::bool*})
+        sources.{core::List::add}(c){(self::Constraint*) →* void};
+    }
+    return this.{self::Planner::makePlan}(sources){(core::List<self::Constraint*>*) →* self::Plan*};
+  }
+  method addPropagate(self::Constraint* c, core::int* mark) → core::bool* {
+    core::List<self::Constraint*>* todo = <self::Constraint*>[c];
+    while (todo.{core::List::length}{core::int*}.{core::num::>}(0){(core::num*) →* core::bool*}) {
+      self::Constraint* d = todo.{core::List::removeLast}(){() →* self::Constraint*};
+      if(d.{self::Constraint::output}(){() →* self::Variable*}.{self::Variable::mark}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} mark) {
+        this.{self::Planner::incrementalRemove}(c){(self::Constraint*) →* void};
+        return false;
+      }
+      d.{self::Constraint::recalculate}(){() →* void};
+      this.{self::Planner::addConstraintsConsumingTo}(d.{self::Constraint::output}(){() →* self::Variable*}, todo){(self::Variable*, core::List<self::Constraint*>*) →* void};
+    }
+    return true;
+  }
+  method removePropagateFrom(self::Variable* out) → core::List<self::Constraint*>* {
+    out.{self::Variable::determinedBy} = null;
+    out.{self::Variable::walkStrength} = #C18;
+    out.{self::Variable::stay} = true;
+    core::List<self::Constraint*>* unsatisfied = <self::Constraint*>[];
+    core::List<self::Variable*>* todo = <self::Variable*>[out];
+    while (todo.{core::List::length}{core::int*}.{core::num::>}(0){(core::num*) →* core::bool*}) {
+      self::Variable* v = todo.{core::List::removeLast}(){() →* self::Variable*};
+      for (core::int* i = 0; i.{core::num::<}(v.{self::Variable::constraints}{core::List<self::Constraint*>*}.{core::List::length}{core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+        self::Constraint* c = v.{self::Variable::constraints}{core::List<self::Constraint*>*}.{core::List::[]}(i){(core::int*) →* self::Constraint*};
+        if(!c.{self::Constraint::isSatisfied}(){() →* core::bool*})
+          unsatisfied.{core::List::add}(c){(self::Constraint*) →* void};
+      }
+      self::Constraint* determining = v.{self::Variable::determinedBy}{self::Constraint*};
+      for (core::int* i = 0; i.{core::num::<}(v.{self::Variable::constraints}{core::List<self::Constraint*>*}.{core::List::length}{core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+        self::Constraint* next = v.{self::Variable::constraints}{core::List<self::Constraint*>*}.{core::List::[]}(i){(core::int*) →* self::Constraint*};
+        if(!(next =={self::Constraint::==}{(dynamic) →* core::bool*} determining) && next.{self::Constraint::isSatisfied}(){() →* core::bool*}) {
+          next.{self::Constraint::recalculate}(){() →* void};
+          todo.{core::List::add}(next.{self::Constraint::output}(){() →* self::Variable*}){(self::Variable*) →* void};
+        }
+      }
+    }
+    return unsatisfied;
+  }
+  method addConstraintsConsumingTo(self::Variable* v, core::List<self::Constraint*>* coll) → void {
+    self::Constraint* determining = v.{self::Variable::determinedBy}{self::Constraint*};
+    for (core::int* i = 0; i.{core::num::<}(v.{self::Variable::constraints}{core::List<self::Constraint*>*}.{core::List::length}{core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+      self::Constraint* c = v.{self::Variable::constraints}{core::List<self::Constraint*>*}.{core::List::[]}(i){(core::int*) →* self::Constraint*};
+      if(!(c =={self::Constraint::==}{(dynamic) →* core::bool*} determining) && c.{self::Constraint::isSatisfied}(){() →* core::bool*})
+        coll.{core::List::add}(c){(self::Constraint*) →* void};
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Plan extends core::Object {
+  field core::List<self::Constraint*>* list = <self::Constraint*>[];
+  synthetic constructor •() → self::Plan*
+    : super core::Object::•()
+    ;
+  method addConstraint(self::Constraint* c) → void {
+    this.{self::Plan::list}{core::List<self::Constraint*>*}.{core::List::add}(c){(self::Constraint*) →* void};
+  }
+  method size() → core::int*
+    return this.{self::Plan::list}{core::List<self::Constraint*>*}.{core::List::length}{core::int*};
+  method execute() → void {
+    for (core::int* i = 0; i.{core::num::<}(this.{self::Plan::list}{core::List<self::Constraint*>*}.{core::List::length}{core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+      this.{self::Plan::list}{core::List<self::Constraint*>*}.{core::List::[]}(i){(core::int*) →* self::Constraint*}.{self::Constraint::execute}(){() →* void};
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field self::Strength* REQUIRED = #C22;
+static const field self::Strength* STRONG_PREFERRED = #C3;
+static const field self::Strength* PREFERRED = #C6;
+static const field self::Strength* STRONG_DEFAULT = #C9;
+static const field self::Strength* NORMAL = #C12;
+static const field self::Strength* WEAK_DEFAULT = #C15;
+static const field self::Strength* WEAKEST = #C18;
+static const field core::int* NONE = #C1;
+static const field core::int* FORWARD = #C4;
+static const field core::int* BACKWARD = #C20;
+static field self::Planner* planner;
+static method main() → dynamic {
+  new self::DeltaBlue::•().{self::DeltaBlue::run}(){() →* void};
+}
+static method chainTest(core::int* n) → void {
+  self::planner = new self::Planner::•();
+  self::Variable* prev = null;
+  self::Variable* first = null;
+  self::Variable* last = null;
+  for (core::int* i = 0; i.{core::num::<=}(n){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+    self::Variable* v = new self::Variable::•("v${i}", 0);
+    if(!(prev == null))
+      new self::EqualityConstraint::•(prev, v, #C22);
+    if(i =={core::num::==}{(core::Object*) →* core::bool*} 0)
+      first = v;
+    if(i =={core::num::==}{(core::Object*) →* core::bool*} n)
+      last = v;
+    prev = v;
+  }
+  new self::StayConstraint::•(last, #C9);
+  self::EditConstraint* edit = new self::EditConstraint::•(first, #C6);
+  self::Plan* plan = self::planner.{self::Planner::extractPlanFromConstraints}(<self::Constraint*>[edit]){(core::List<self::Constraint*>*) →* self::Plan*};
+  for (core::int* i = 0; i.{core::num::<}(100){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+    first.{self::Variable::value} = i;
+    plan.{self::Plan::execute}(){() →* void};
+    if(!(last.{self::Variable::value}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} i)) {
+      core::print("Chain test failed:");
+      core::print("Expected last value to be ${i} but it was ${last.{self::Variable::value}{core::int*}}.");
+    }
+  }
+}
+static method projectionTest(core::int* n) → void {
+  self::planner = new self::Planner::•();
+  self::Variable* scale = new self::Variable::•("scale", 10);
+  self::Variable* offset = new self::Variable::•("offset", 1000);
+  self::Variable* src = null;
+  self::Variable* dst = null;
+  core::List<self::Variable*>* dests = <self::Variable*>[];
+  for (core::int* i = 0; i.{core::num::<}(n){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+    src = new self::Variable::•("src", i);
+    dst = new self::Variable::•("dst", i);
+    dests.{core::List::add}(dst){(self::Variable*) →* void};
+    new self::StayConstraint::•(src, #C12);
+    new self::ScaleConstraint::•(src, scale, offset, dst, #C22);
+  }
+  self::change(src, 17);
+  if(!(dst.{self::Variable::value}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} 1170))
+    core::print("Projection 1 failed");
+  self::change(dst, 1050);
+  if(!(src.{self::Variable::value}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} 5))
+    core::print("Projection 2 failed");
+  self::change(scale, 5);
+  for (core::int* i = 0; i.{core::num::<}(n.{core::num::-}(1){(core::num*) →* core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+    if(!(dests.{core::List::[]}(i){(core::int*) →* self::Variable*}.{self::Variable::value}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} i.{core::num::*}(5){(core::num*) →* core::int*}.{core::num::+}(1000){(core::num*) →* core::int*}))
+      core::print("Projection 3 failed");
+  }
+  self::change(offset, 2000);
+  for (core::int* i = 0; i.{core::num::<}(n.{core::num::-}(1){(core::num*) →* core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+    if(!(dests.{core::List::[]}(i){(core::int*) →* self::Variable*}.{self::Variable::value}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} i.{core::num::*}(5){(core::num*) →* core::int*}.{core::num::+}(2000){(core::num*) →* core::int*}))
+      core::print("Projection 4 failed");
+  }
+}
+static method change(self::Variable* v, core::int* newValue) → void {
+  self::EditConstraint* edit = new self::EditConstraint::•(v, #C6);
+  self::Plan* plan = self::planner.{self::Planner::extractPlanFromConstraints}(<self::EditConstraint*>[edit]){(core::List<self::Constraint*>*) →* self::Plan*};
+  for (core::int* i = 0; i.{core::num::<}(10){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+    v.{self::Variable::value} = newValue;
+    plan.{self::Plan::execute}(){() →* void};
+  }
+  edit.{self::Constraint::destroyConstraint}(){() →* void};
+}
+
+constants  {
+  #C1 = 1
+  #C2 = "strongPreferred"
+  #C3 = self::Strength {value:#C1, name:#C2}
+  #C4 = 2
+  #C5 = "preferred"
+  #C6 = self::Strength {value:#C4, name:#C5}
+  #C7 = 3
+  #C8 = "strongDefault"
+  #C9 = self::Strength {value:#C7, name:#C8}
+  #C10 = 4
+  #C11 = "normal"
+  #C12 = self::Strength {value:#C10, name:#C11}
+  #C13 = 5
+  #C14 = "weakDefault"
+  #C15 = self::Strength {value:#C13, name:#C14}
+  #C16 = 6
+  #C17 = "weakest"
+  #C18 = self::Strength {value:#C16, name:#C17}
+  #C19 = <self::Strength*>[#C3, #C6, #C9, #C12, #C15, #C18]
+  #C20 = 0
+  #C21 = "required"
+  #C22 = self::Strength {value:#C20, name:#C21}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///DeltaBlue.dart:
+- Strength. (from org-dartlang-testcase:///DeltaBlue.dart:59:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/abstract_instantiation.dart.weak.modular.expect b/pkg/front_end/testcases/general/abstract_instantiation.dart.weak.modular.expect
new file mode 100644
index 0000000..d76d693
--- /dev/null
+++ b/pkg/front_end/testcases/general/abstract_instantiation.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/abstract_instantiation.dart:8:17: Error: Factory redirects to class 'A', which is abstract and can't be instantiated.
+//   factory B() = A;
+//                 ^
+//
+// pkg/front_end/testcases/general/abstract_instantiation.dart:8:17: Error: The constructor function type 'A Function()' isn't a subtype of 'B Function()'.
+//  - 'A' is from 'pkg/front_end/testcases/general/abstract_instantiation.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/general/abstract_instantiation.dart'.
+//   factory B() = A;
+//                 ^
+//
+// pkg/front_end/testcases/general/abstract_instantiation.dart:12:7: Error: The class 'A' is abstract and can't be instantiated.
+//   new A();
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+abstract class B extends core::Object implements self::A {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  static factory •() → self::B
+    return invalid-expression "pkg/front_end/testcases/general/abstract_instantiation.dart:8:17: Error: The constructor function type 'A Function()' isn't a subtype of 'B Function()'.
+ - 'A' is from 'pkg/front_end/testcases/general/abstract_instantiation.dart'.
+ - 'B' is from 'pkg/front_end/testcases/general/abstract_instantiation.dart'.
+  factory B() = A;
+                ^";
+}
+static method test() → dynamic {
+  throw new core::AbstractClassInstantiationError::•("A");
+  invalid-expression "pkg/front_end/testcases/general/abstract_instantiation.dart:8:17: Error: The constructor function type 'A Function()' isn't a subtype of 'B Function()'.
+ - 'A' is from 'pkg/front_end/testcases/general/abstract_instantiation.dart'.
+ - 'B' is from 'pkg/front_end/testcases/general/abstract_instantiation.dart'.
+  factory B() = A;
+                ^";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::B::•
+}
diff --git a/pkg/front_end/testcases/general/abstract_members.dart.weak.modular.expect b/pkg/front_end/testcases/general/abstract_members.dart.weak.modular.expect
new file mode 100644
index 0000000..d874a11
--- /dev/null
+++ b/pkg/front_end/testcases/general/abstract_members.dart.weak.modular.expect
@@ -0,0 +1,442 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/abstract_members.dart:21:16: Error: Can't inherit members that conflict with each other.
+// abstract class A implements Interface1, Interface2, Interface3 {
+//                ^
+// pkg/front_end/testcases/general/abstract_members.dart:8:8: Context: This is one inherited member.
+//   void interfaceMethod1() {}
+//        ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:14:7: Context: This is the other inherited member.
+//   var interfaceMethod1;
+//       ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/abstract_members.dart:29:16: Error: Can't inherit members that conflict with each other.
+// abstract class B extends A {
+//                ^
+// pkg/front_end/testcases/general/abstract_members.dart:8:8: Context: This is one inherited member.
+//   void interfaceMethod1() {}
+//        ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:14:7: Context: This is the other inherited member.
+//   var interfaceMethod1;
+//       ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/abstract_members.dart:35:7: Error: Can't inherit members that conflict with each other.
+// class MyClass extends B {
+//       ^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:8:8: Context: This is one inherited member.
+//   void interfaceMethod1() {}
+//        ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:14:7: Context: This is the other inherited member.
+//   var interfaceMethod1;
+//       ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/abstract_members.dart:35:7: Error: The non-abstract class 'MyClass' is missing implementations for these members:
+//  - A.abstractMethod
+//  - A.property1=
+//  - A.property3=
+//  - Interface1.interfaceMethod1
+//  - Interface2.interfaceMethod1
+//  - Interface2.interfaceMethod2
+//  - Interface3.interfaceMethod3
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class MyClass extends B {
+//       ^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:23:3: Context: 'A.abstractMethod' is defined here.
+//   abstractMethod();
+//   ^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:24:12: Context: 'A.property1=' is defined here.
+//   void set property1(_);
+//            ^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:26:12: Context: 'A.property3=' is defined here.
+//   void set property3(_);
+//            ^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:8:8: Context: 'Interface1.interfaceMethod1' is defined here.
+//   void interfaceMethod1() {}
+//        ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:14:7: Context: 'Interface2.interfaceMethod1' is defined here.
+//   var interfaceMethod1;
+//       ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:12:8: Context: 'Interface2.interfaceMethod2' is defined here.
+//   void interfaceMethod2() {}
+//        ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:18:8: Context: 'Interface3.interfaceMethod3' is defined here.
+//   void interfaceMethod3() {}
+//        ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/abstract_members.dart:44:7: Error: Can't inherit members that conflict with each other.
+// class MyMock1 extends B {
+//       ^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:8:8: Context: This is one inherited member.
+//   void interfaceMethod1() {}
+//        ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:14:7: Context: This is the other inherited member.
+//   var interfaceMethod1;
+//       ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/abstract_members.dart:50:7: Error: Can't inherit members that conflict with each other.
+// class MyMock2 extends MyMock1 {
+//       ^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:8:8: Context: This is one inherited member.
+//   void interfaceMethod1() {}
+//        ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:14:7: Context: This is the other inherited member.
+//   var interfaceMethod1;
+//       ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/abstract_members.dart:56:7: Error: Can't inherit members that conflict with each other.
+// class MyMock3 extends B {
+//       ^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:8:8: Context: This is one inherited member.
+//   void interfaceMethod1() {}
+//        ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:14:7: Context: This is the other inherited member.
+//   var interfaceMethod1;
+//       ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/abstract_members.dart:56:7: Error: The non-abstract class 'MyMock3' is missing implementations for these members:
+//  - A.abstractMethod
+//  - A.property1=
+//  - A.property2=
+//  - A.property3=
+//  - Interface1.interfaceMethod1
+//  - Interface2.interfaceMethod1
+//  - Interface2.interfaceMethod2
+//  - Interface3.interfaceMethod3
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class MyMock3 extends B {
+//       ^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:23:3: Context: 'A.abstractMethod' is defined here.
+//   abstractMethod();
+//   ^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:24:12: Context: 'A.property1=' is defined here.
+//   void set property1(_);
+//            ^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:25:12: Context: 'A.property2=' is defined here.
+//   void set property2(_);
+//            ^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:26:12: Context: 'A.property3=' is defined here.
+//   void set property3(_);
+//            ^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:8:8: Context: 'Interface1.interfaceMethod1' is defined here.
+//   void interfaceMethod1() {}
+//        ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:14:7: Context: 'Interface2.interfaceMethod1' is defined here.
+//   var interfaceMethod1;
+//       ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:12:8: Context: 'Interface2.interfaceMethod2' is defined here.
+//   void interfaceMethod2() {}
+//        ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:18:8: Context: 'Interface3.interfaceMethod3' is defined here.
+//   void interfaceMethod3() {}
+//        ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/abstract_members.dart:66:16: Error: Can't inherit members that conflict with each other.
+// abstract class D extends C implements Interface2 {}
+//                ^
+// pkg/front_end/testcases/general/abstract_members.dart:14:7: Context: This is one inherited member.
+//   var interfaceMethod1;
+//       ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:61:8: Context: This is the other inherited member.
+//   void interfaceMethod1(_) {}
+//        ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/abstract_members.dart:74:16: Error: Can't inherit members that conflict with each other.
+// abstract class F extends E implements Interface1 {}
+//                ^
+// pkg/front_end/testcases/general/abstract_members.dart:8:8: Context: This is one inherited member.
+//   void interfaceMethod1() {}
+//        ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/abstract_members.dart:69:12: Context: This is the other inherited member.
+//   void set interfaceMethod1(_) {}
+//            ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/abstract_members.dart:86:16: Error: Can't inherit members that conflict with each other.
+// abstract class H extends G implements Foo {}
+//                ^
+// pkg/front_end/testcases/general/abstract_members.dart:77:8: Context: This is one inherited member.
+//   void foo() {}
+//        ^^^
+// pkg/front_end/testcases/general/abstract_members.dart:81:14: Context: This is the other inherited member.
+//   Object get foo => null;
+//              ^^^
+//
+// pkg/front_end/testcases/general/abstract_members.dart:98:16: Error: Can't inherit members that conflict with each other.
+// abstract class J extends I implements Bar {}
+//                ^
+// pkg/front_end/testcases/general/abstract_members.dart:89:14: Context: This is one inherited member.
+//   Object get foo => null;
+//              ^^^
+// pkg/front_end/testcases/general/abstract_members.dart:93:10: Context: This is the other inherited member.
+//   Object foo() {}
+//          ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Interface1 extends core::Object {
+  synthetic constructor •() → self::Interface1*
+    : super core::Object::•()
+    ;
+  method interfaceMethod1() → void {}
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Interface2 extends core::Object {
+  field dynamic interfaceMethod1 = null;
+  synthetic constructor •() → self::Interface2*
+    : super core::Object::•()
+    ;
+  method interfaceMethod2() → void {}
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Interface3 extends core::Object {
+  synthetic constructor •() → self::Interface3*
+    : super core::Object::•()
+    ;
+  method interfaceMethod3() → void {}
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class A extends core::Object implements self::Interface1, self::Interface2, self::Interface3 {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method aMethod() → dynamic {}
+  abstract method abstractMethod() → dynamic;
+  abstract set property1(dynamic _) → void;
+  abstract set property2(dynamic _) → void;
+  abstract set property3(dynamic _) → void;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends self::A {
+  final field dynamic property1 = null;
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  method aMethod() → dynamic {}
+  method bMethod() → dynamic {}
+}
+class MyClass extends self::B {
+  field dynamic property2 = null;
+  synthetic constructor •() → self::MyClass*
+    : super self::B::•()
+    ;
+  method aaMethod() → dynamic {}
+  method aMethod() → dynamic {}
+  method bMethod() → dynamic {}
+  method cMethod() → dynamic {}
+}
+class MyMock1 extends self::B {
+  synthetic constructor •() → self::MyMock1*
+    : super self::B::•()
+    ;
+  method noSuchMethod(core::Invocation* _) → dynamic
+    return null;
+  no-such-method-forwarder method interfaceMethod2() → void
+    return this.{self::MyMock1::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method abstractMethod() → dynamic
+    return this.{self::MyMock1::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} dynamic;
+  no-such-method-forwarder method interfaceMethod1() → void
+    return this.{self::MyMock1::noSuchMethod}(new core::_InvocationMirror::_withType(#C6, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method interfaceMethod3() → void
+    return this.{self::MyMock1::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder set property3(dynamic _) → void
+    return this.{self::MyMock1::noSuchMethod}(new core::_InvocationMirror::_withType(#C8, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[_]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder set interfaceMethod1(dynamic value) → void
+    return this.{self::MyMock1::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder set property1(dynamic _) → void
+    return this.{self::MyMock1::noSuchMethod}(new core::_InvocationMirror::_withType(#C10, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[_]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder set property2(dynamic _) → void
+    return this.{self::MyMock1::noSuchMethod}(new core::_InvocationMirror::_withType(#C11, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[_]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+class MyMock2 extends self::MyMock1 {
+  synthetic constructor •() → self::MyMock2*
+    : super self::MyMock1::•()
+    ;
+  abstract method noSuchMethod(core::Invocation* _) → dynamic;
+}
+class MyMock3 extends self::B {
+  synthetic constructor •() → self::MyMock3*
+    : super self::B::•()
+    ;
+  abstract method noSuchMethod(core::Invocation* _) → dynamic;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method interfaceMethod1(dynamic _) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D extends self::C implements self::Interface2 {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+}
+class E extends core::Object {
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  set interfaceMethod1(dynamic _) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class F extends self::E implements self::Interface1 {
+  synthetic constructor •() → self::F*
+    : super self::E::•()
+    ;
+}
+class Foo extends core::Object {
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  method foo() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class G extends core::Object {
+  synthetic constructor •() → self::G*
+    : super core::Object::•()
+    ;
+  get foo() → core::Object*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class H extends self::G implements self::Foo {
+  synthetic constructor •() → self::H*
+    : super self::G::•()
+    ;
+}
+class Bar extends core::Object {
+  synthetic constructor •() → self::Bar*
+    : super core::Object::•()
+    ;
+  get foo() → core::Object*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  method foo() → core::Object* {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class J extends self::I implements self::Bar {
+  synthetic constructor •() → self::J*
+    : super self::I::•()
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #interfaceMethod2
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+  #C5 = #abstractMethod
+  #C6 = #interfaceMethod1
+  #C7 = #interfaceMethod3
+  #C8 = #property3=
+  #C9 = #interfaceMethod1=
+  #C10 = #property1=
+  #C11 = #property2=
+}
diff --git a/pkg/front_end/testcases/general/abstract_operator_override.dart.weak.modular.expect b/pkg/front_end/testcases/general/abstract_operator_override.dart.weak.modular.expect
new file mode 100644
index 0000000..6b85486
--- /dev/null
+++ b/pkg/front_end/testcases/general/abstract_operator_override.dart.weak.modular.expect
@@ -0,0 +1,124 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/abstract_operator_override.dart:12:7: Error: The implementation of '+' in the non-abstract class 'B' does not conform to its interface.
+// class B extends A {
+//       ^
+// pkg/front_end/testcases/general/abstract_operator_override.dart:6:18: Context: The parameter 'b' of the method 'A.+' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'B.+'.
+//  - 'B' is from 'pkg/front_end/testcases/general/abstract_operator_override.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/abstract_operator_override.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   A operator +(B b) => new A();
+//                  ^
+// pkg/front_end/testcases/general/abstract_operator_override.dart:13:14: Context: This is the overridden method ('+').
+//   A operator +(A a);
+//              ^
+//
+// pkg/front_end/testcases/general/abstract_operator_override.dart:12:7: Error: The implementation of 'unary-' in the non-abstract class 'B' does not conform to its interface.
+// class B extends A {
+//       ^
+// pkg/front_end/testcases/general/abstract_operator_override.dart:7:14: Context: The return type of the method 'A.unary-' is 'A', which does not match the return type, 'B', of the overridden method, 'B.unary-'.
+//  - 'A' is from 'pkg/front_end/testcases/general/abstract_operator_override.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/general/abstract_operator_override.dart'.
+// Change to a subtype of 'B'.
+//   A operator -() => new A();
+//              ^
+// pkg/front_end/testcases/general/abstract_operator_override.dart:14:14: Context: This is the overridden method ('unary-').
+//   B operator -();
+//              ^
+//
+// pkg/front_end/testcases/general/abstract_operator_override.dart:12:7: Error: The implementation of '[]' in the non-abstract class 'B' does not conform to its interface.
+// class B extends A {
+//       ^
+// pkg/front_end/testcases/general/abstract_operator_override.dart:8:19: Context: The parameter 'b' of the method 'A.[]' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'B.[]'.
+//  - 'B' is from 'pkg/front_end/testcases/general/abstract_operator_override.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/abstract_operator_override.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   A operator [](B b) => new A();
+//                   ^
+// pkg/front_end/testcases/general/abstract_operator_override.dart:15:14: Context: This is the overridden method ('[]').
+//   A operator [](A a);
+//              ^
+//
+// pkg/front_end/testcases/general/abstract_operator_override.dart:12:7: Error: The implementation of '[]=' in the non-abstract class 'B' does not conform to its interface.
+// class B extends A {
+//       ^
+// pkg/front_end/testcases/general/abstract_operator_override.dart:9:23: Context: The parameter 'b1' of the method 'A.[]=' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'B.[]='.
+//  - 'B' is from 'pkg/front_end/testcases/general/abstract_operator_override.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/abstract_operator_override.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   void operator []=(B b1, B b2) {}
+//                       ^
+// pkg/front_end/testcases/general/abstract_operator_override.dart:16:17: Context: This is the overridden method ('[]=').
+//   void operator []=(A a, B b);
+//                 ^
+//
+// pkg/front_end/testcases/general/abstract_operator_override.dart:19:7: Error: The implementation of '[]' in the non-abstract class 'C' does not conform to its interface.
+// class C extends A {
+//       ^
+// pkg/front_end/testcases/general/abstract_operator_override.dart:8:14: Context: The return type of the method 'A.[]' is 'A', which does not match the return type, 'B', of the overridden method, 'C.[]'.
+//  - 'A' is from 'pkg/front_end/testcases/general/abstract_operator_override.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/general/abstract_operator_override.dart'.
+// Change to a subtype of 'B'.
+//   A operator [](B b) => new A();
+//              ^
+// pkg/front_end/testcases/general/abstract_operator_override.dart:20:14: Context: This is the overridden method ('[]').
+//   B operator [](B b);
+//              ^
+//
+// pkg/front_end/testcases/general/abstract_operator_override.dart:19:7: Error: The implementation of '[]=' in the non-abstract class 'C' does not conform to its interface.
+// class C extends A {
+//       ^
+// pkg/front_end/testcases/general/abstract_operator_override.dart:9:29: Context: The parameter 'b2' of the method 'A.[]=' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'C.[]='.
+//  - 'B' is from 'pkg/front_end/testcases/general/abstract_operator_override.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/abstract_operator_override.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   void operator []=(B b1, B b2) {}
+//                             ^
+// pkg/front_end/testcases/general/abstract_operator_override.dart:21:17: Context: This is the overridden method ('[]=').
+//   void operator []=(B b, A a);
+//                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator +(self::B* b) → self::A*
+    return new self::A::•();
+  operator unary-() → self::A*
+    return new self::A::•();
+  operator [](self::B* b) → self::A*
+    return new self::A::•();
+  operator []=(self::B* b1, self::B* b2) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  abstract operator +(self::A* a) → self::A*;
+  abstract operator unary-() → self::B*;
+  abstract operator [](self::A* a) → self::A*;
+  abstract operator []=(self::A* a, self::B* b) → void;
+}
+class C extends self::A {
+  synthetic constructor •() → self::C*
+    : super self::A::•()
+    ;
+  abstract operator [](self::B* b) → self::B*;
+  abstract operator []=(self::B* b, self::A* a) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/abstract_overrides_concrete.dart.weak.modular.expect b/pkg/front_end/testcases/general/abstract_overrides_concrete.dart.weak.modular.expect
new file mode 100644
index 0000000..90c7a87
--- /dev/null
+++ b/pkg/front_end/testcases/general/abstract_overrides_concrete.dart.weak.modular.expect
@@ -0,0 +1,102 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/abstract_overrides_concrete.dart:17:7: Error: The implementation of 'foo' in the non-abstract class 'C' does not conform to its interface.
+// class C extends B {}
+//       ^
+// pkg/front_end/testcases/general/abstract_overrides_concrete.dart:6:8: Context: The method 'A.foo' has fewer positional arguments than those of overridden method 'B.foo'.
+//   void foo() {}
+//        ^
+// pkg/front_end/testcases/general/abstract_overrides_concrete.dart:14:8: Context: This is the overridden method ('foo').
+//   void foo([a]);
+//        ^
+//
+// pkg/front_end/testcases/general/abstract_overrides_concrete.dart:19:7: Error: The implementation of 'foo' in the non-abstract class 'D' does not conform to its interface.
+// class D extends A implements I {}
+//       ^
+// pkg/front_end/testcases/general/abstract_overrides_concrete.dart:6:8: Context: The method 'A.foo' has fewer positional arguments than those of overridden method 'I.foo'.
+//   void foo() {}
+//        ^
+// pkg/front_end/testcases/general/abstract_overrides_concrete.dart:10:8: Context: This is the overridden method ('foo').
+//   void foo([a]);
+//        ^
+//
+// pkg/front_end/testcases/general/abstract_overrides_concrete.dart:23:7: Error: The implementation of 'foo' in the non-abstract class 'F' does not conform to its interface.
+// class F extends E {}
+//       ^
+// pkg/front_end/testcases/general/abstract_overrides_concrete.dart:6:8: Context: The method 'A.foo' has fewer positional arguments than those of overridden method 'I.foo'.
+//   void foo() {}
+//        ^
+// pkg/front_end/testcases/general/abstract_overrides_concrete.dart:10:8: Context: This is the overridden method ('foo').
+//   void foo([a]);
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method foo() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  abstract method foo([dynamic a = #C1]) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  abstract method foo([dynamic a = #C1]) → void;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class D extends self::A implements self::I {
+  synthetic constructor •() → self::D*
+    : super self::A::•()
+    ;
+  abstract member-signature method foo([dynamic a = #C1]) → void; -> self::I::foo
+}
+abstract class E extends self::A implements self::I {
+  synthetic constructor •() → self::E*
+    : super self::A::•()
+    ;
+  abstract member-signature method foo([dynamic a = #C1]) → void; -> self::I::foo
+}
+class F extends self::E {
+  synthetic constructor •() → self::F*
+    : super self::E::•()
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/abstract_overrides_concrete_with_no_such_method.dart.weak.modular.expect b/pkg/front_end/testcases/general/abstract_overrides_concrete_with_no_such_method.dart.weak.modular.expect
new file mode 100644
index 0000000..882db16
--- /dev/null
+++ b/pkg/front_end/testcases/general/abstract_overrides_concrete_with_no_such_method.dart.weak.modular.expect
@@ -0,0 +1,58 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method foo() → self::A*
+    return null;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  abstract method foo() → self::B*;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* _) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C implements self::B {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  no-such-method-forwarder method foo() → self::B*
+    return this.{self::C::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} self::B*;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/general/accessors.dart.weak.modular.expect b/pkg/front_end/testcases/general/accessors.dart.weak.modular.expect
new file mode 100644
index 0000000..d09f07b
--- /dev/null
+++ b/pkg/front_end/testcases/general/accessors.dart.weak.modular.expect
@@ -0,0 +1,90 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/accessors.dart:16:13: Error: The getter 'onlySetter' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/general/accessors.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'onlySetter'.
+//       print(onlySetter);
+//             ^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/accessors.dart:25:11: Error: The getter 'onlySetter' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/general/accessors.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'onlySetter'.
+//     print(onlySetter);
+//           ^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/accessors.dart:40:11: Error: Getter not found: 'onlySetter'.
+//     print(onlySetter);
+//           ^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  set onlySetter(dynamic value) → void {
+    core::print("C.onlySetter called with ${value}.");
+  }
+  method testC() → dynamic {
+    try {
+      core::print(invalid-expression "pkg/front_end/testcases/general/accessors.dart:16:13: Error: The getter 'onlySetter' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/general/accessors.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'onlySetter'.
+      print(onlySetter);
+            ^^^^^^^^^^" in this{<unresolved>}.onlySetter);
+      throw "No error thrown";
+    }
+    on core::NoSuchMethodError* catch(final core::NoSuchMethodError* e) {
+      core::print("Expected error: ${e}");
+    }
+    this.{self::C::onlySetter} = "hest";
+  }
+  method testD() → dynamic {
+    core::print(invalid-expression "pkg/front_end/testcases/general/accessors.dart:25:11: Error: The getter 'onlySetter' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/general/accessors.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'onlySetter'.
+    print(onlySetter);
+          ^^^^^^^^^^" in this{<unresolved>}.onlySetter);
+    this.{self::C::onlySetter} = "hest";
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  get onlySetter() → core::String*
+    return "D.onlySetter called.";
+  set onlySetter(dynamic value) → void {
+    core::print("D.onlySetter called with ${value}.");
+  }
+}
+static set onlySetter(dynamic value) → void {
+  core::print("onlySetter called with ${value}.");
+}
+static method main() → dynamic {
+  try {
+    core::print(invalid-expression "pkg/front_end/testcases/general/accessors.dart:40:11: Error: Getter not found: 'onlySetter'.
+    print(onlySetter);
+          ^^^^^^^^^^");
+    throw "No error thrown";
+  }
+  on core::NoSuchMethodError* catch(final core::NoSuchMethodError* e) {
+    core::print("Expected error: ${e}");
+  }
+  self::onlySetter = "fisk";
+  new self::C::•().{self::C::testC}(){() →* dynamic};
+  new self::D::•().{self::C::testD}(){() →* dynamic};
+}
diff --git a/pkg/front_end/testcases/general/all_variances.dart.weak.modular.expect b/pkg/front_end/testcases/general/all_variances.dart.weak.modular.expect
new file mode 100644
index 0000000..f7afd1b
--- /dev/null
+++ b/pkg/front_end/testcases/general/all_variances.dart.weak.modular.expect
@@ -0,0 +1,6 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef F<unrelated W extends core::Object* = dynamic, X extends core::Object* = dynamic, contravariant Y extends core::Object* = dynamic, invariant Z extends core::Object* = dynamic> = (Y*, (Z*) →* Z*) →* X*;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/ambiguous_exports.dart.weak.modular.expect b/pkg/front_end/testcases/general/ambiguous_exports.dart.weak.modular.expect
new file mode 100644
index 0000000..8155e8e
--- /dev/null
+++ b/pkg/front_end/testcases/general/ambiguous_exports.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/ambiguous_exports.dart:7:1: Error: 'main' is exported from both 'pkg/front_end/testcases/general/hello.dart' and 'pkg/front_end/testcases/general/map.dart'.
+// export 'map.dart' show main;
+// ^
+//
+import self as self;
+import "dart:core" as core;
+
+export "org-dartlang-testcase:///hello.dart" show main;
+export "org-dartlang-testcase:///map.dart" show main;
+
+static const field dynamic _exports# = #C1;
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::print("Hello, World!");
+}
+
+library;
+import self as self3;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::print(core::Map::•<dynamic, dynamic>());
+}
+
+constants  {
+  #C1 = "{\"main\":\"'main' is exported from both 'pkg/front_end/testcases/general/hello.dart' and 'pkg/front_end/testcases/general/map.dart'.\"}"
+}
diff --git a/pkg/front_end/testcases/general/annotation_eof.dart.weak.modular.expect b/pkg/front_end/testcases/general/annotation_eof.dart.weak.modular.expect
new file mode 100644
index 0000000..f4d0e53
--- /dev/null
+++ b/pkg/front_end/testcases/general/annotation_eof.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/annotation_eof.dart:10:1: Error: Expected a declaration, but got ''.
+//
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::print("There is a dangling annotation at the end of this file");
+}
diff --git a/pkg/front_end/testcases/general/annotation_on_enum_values.dart.weak.modular.expect b/pkg/front_end/testcases/general/annotation_on_enum_values.dart.weak.modular.expect
new file mode 100644
index 0000000..80eb1d7
--- /dev/null
+++ b/pkg/front_end/testcases/general/annotation_on_enum_values.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Fisk<T extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field self::Fisk::T* x;
+  const constructor fisk(self::Fisk::T* x) → self::Fisk<self::Fisk::T*>*
+    : self::Fisk::x = x, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Foo extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::Foo*>* values = #C10;
+  @#C11
+  static const field self::Foo* bar = #C3;
+  @#C12
+  static const field self::Foo* baz = #C6;
+  static const field self::Foo* cafebabe = #C9;
+  const constructor •(core::int* index, core::String* name) → self::Foo*
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String*
+    return "Foo.${this.{core::_Enum::_name}{core::String}}";
+  abstract member-signature get index() → core::int*; -> core::_Enum::index
+  abstract member-signature get _name() → core::String*; -> core::_Enum::_name
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field core::int* hest = #C11;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+  #C2 = "bar"
+  #C3 = self::Foo {index:#C1, _name:#C2}
+  #C4 = 1
+  #C5 = "baz"
+  #C6 = self::Foo {index:#C4, _name:#C5}
+  #C7 = 2
+  #C8 = "cafebabe"
+  #C9 = self::Foo {index:#C7, _name:#C8}
+  #C10 = <self::Foo*>[#C3, #C6, #C9]
+  #C11 = 42
+  #C12 = self::Fisk<core::int*> {x:#C11}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///annotation_on_enum_values.dart:
+- Foo. (from org-dartlang-testcase:///annotation_on_enum_values.dart:15:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:76:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Fisk.fisk (from org-dartlang-testcase:///annotation_on_enum_values.dart:12:9)
diff --git a/pkg/front_end/testcases/general/annotation_top.dart.weak.modular.expect b/pkg/front_end/testcases/general/annotation_top.dart.weak.modular.expect
new file mode 100644
index 0000000..b8fa4b8
--- /dev/null
+++ b/pkg/front_end/testcases/general/annotation_top.dart.weak.modular.expect
@@ -0,0 +1,65 @@
+@#C1
+@#C2
+library test;
+import self as self;
+import "dart:core" as core;
+
+@#C1
+@#C2
+typedef F1 = () →* void;
+@#C1
+@#C2
+typedef F2 = () →* void;
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor •(core::int* value) → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+@#C1
+@#C2
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field core::Object* a = #C1;
+@#C1
+@#C2
+static field core::int* f1;
+@#C1
+@#C2
+static field core::int* f2;
+@#C1
+@#C2
+static method main() → void {}
+
+constants  {
+  #C1 = core::Object {}
+  #C2 = self::A {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///annotation_top.dart:
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- A. (from org-dartlang-testcase:///annotation_top.dart:12:9)
diff --git a/pkg/front_end/testcases/general/annotation_typedef_formals.dart.weak.modular.expect b/pkg/front_end/testcases/general/annotation_typedef_formals.dart.weak.modular.expect
new file mode 100644
index 0000000..d6f9911
--- /dev/null
+++ b/pkg/front_end/testcases/general/annotation_typedef_formals.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef F = (@#C1 core::int* x, core::num* y, {@#C2 @#C3 core::String* z, core::Object* w}) →* void;
+typedef G = (@#C1 core::int* a, core::num* b, [@#C2 @#C3 core::String* c, core::Object* d]) →* void;
+static const field core::int* foo = #C1;
+static const field core::int* bar = #C2;
+static const field core::int* baz = #C3;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 21
+  #C2 = 42
+  #C3 = 84
+}
diff --git a/pkg/front_end/testcases/general/annotation_typedef_formals_resolution.dart.weak.modular.expect b/pkg/front_end/testcases/general/annotation_typedef_formals_resolution.dart.weak.modular.expect
new file mode 100644
index 0000000..9bab9c9
--- /dev/null
+++ b/pkg/front_end/testcases/general/annotation_typedef_formals_resolution.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef F = (@#C1 core::int* app) →* core::int*;
+static const field core::int* app = #C1;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+}
diff --git a/pkg/front_end/testcases/general/annotation_variable_declaration.dart.weak.modular.expect b/pkg/front_end/testcases/general/annotation_variable_declaration.dart.weak.modular.expect
new file mode 100644
index 0000000..de080e6
--- /dev/null
+++ b/pkg/front_end/testcases/general/annotation_variable_declaration.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef hest_t = ({@#C1 dynamic named}) →* dynamic;
+class Bar extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::Bar*
+    : super core::Object::•()
+    ;
+  const constructor named(dynamic x) → self::Bar*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Baz extends core::Object {
+  constructor •(@#C1 dynamic constructorFormal) → self::Baz*
+    : super core::Object::•()
+    ;
+  static factory bazFactory(@#C1 dynamic factoryFormal) → self::Baz*
+    return null;
+  method fisk(@#C1 dynamic formal1, @#C2 dynamic formal2, @#C2 dynamic formal3, @#C1 @#C2 dynamic formal4, [@#C1 dynamic optional = #C3]) → dynamic {
+    @#C1 dynamic local1;
+    @#C2 dynamic local2;
+    @#C2 dynamic local3;
+    @#C1 @#C2 dynamic local4;
+    @#C1 core::String* localWithInitializer = "hello";
+    @#C1 @#C2 dynamic localGroupPart1;
+    @#C1 @#C2 dynamic localGroupPart2;
+    function naebdyr(@#C1 dynamic nestedFormal) → Null
+      return null;
+    (dynamic) →* Null roedmus = (@#C1 dynamic closureFormal) → Null => null;
+  }
+  method hest({@#C1 dynamic named = #C3}) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field core::int* foo = #C1;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 42
+  #C2 = self::Bar {}
+  #C3 = null
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///annotation_variable_declaration.dart:
+- Bar. (from org-dartlang-testcase:///annotation_variable_declaration.dart:8:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Bar.named (from org-dartlang-testcase:///annotation_variable_declaration.dart:9:9)
diff --git a/pkg/front_end/testcases/general/argument.dart.weak.modular.expect b/pkg/front_end/testcases/general/argument.dart.weak.modular.expect
new file mode 100644
index 0000000..e667193
--- /dev/null
+++ b/pkg/front_end/testcases/general/argument.dart.weak.modular.expect
@@ -0,0 +1,52 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class Base extends core::Object {
+  synthetic constructor •() → self::Base*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Foo extends self::Base {
+  synthetic constructor •() → self::Foo*
+    : super self::Base::•()
+    ;
+}
+class Bar extends self::Base {
+  synthetic constructor •() → self::Bar*
+    : super self::Base::•()
+    ;
+}
+class Baz extends self::Base {
+  synthetic constructor •() → self::Baz*
+    : super self::Base::•()
+    ;
+}
+static method foo(dynamic x) → void {}
+static method bar(dynamic x) → void {}
+static method foo_escaped(dynamic x) → void {}
+static method bar_escaped(dynamic x) → void {}
+static method escape(dynamic fn) → void {
+  fn{dynamic}.call(new self::Baz::•());
+}
+static method main() → dynamic {
+  self::foo(new self::Foo::•());
+  self::bar(new self::Bar::•());
+  self::escape(#C1);
+  self::escape(#C2);
+}
+
+constants  {
+  #C1 = static-tearoff self::foo_escaped
+  #C2 = static-tearoff self::bar_escaped
+}
diff --git a/pkg/front_end/testcases/general/argument_mismatch.dart.weak.modular.expect b/pkg/front_end/testcases/general/argument_mismatch.dart.weak.modular.expect
new file mode 100644
index 0000000..b0d5171
--- /dev/null
+++ b/pkg/front_end/testcases/general/argument_mismatch.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/argument_mismatch.dart:8:6: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//   foo(null);
+//      ^
+// pkg/front_end/testcases/general/argument_mismatch.dart:5:1: Context: Found this candidate, but the arguments don't match.
+// foo() {}
+// ^^^
+//
+import self as self;
+
+static method foo() → dynamic {}
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/argument_mismatch.dart:8:6: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+  foo(null);
+     ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/arithmetic.dart.weak.modular.expect b/pkg/front_end/testcases/general/arithmetic.dart.weak.modular.expect
new file mode 100644
index 0000000..0e703fd
--- /dev/null
+++ b/pkg/front_end/testcases/general/arithmetic.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method foo(core::int* x, core::int* y) → core::int* {
+  core::int* z = x.{core::num::+}(y){(core::num*) →* core::int*};
+  return z.{core::int::<<}(4){(core::int*) →* core::int*};
+}
+static method loop(core::List<dynamic>* xs) → void {
+  core::int* _ = xs.{core::List::length}{core::int*};
+  for (core::int* i = 0; i.{core::num::<}(xs.{core::List::length}{core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+  }
+}
+static method main() → dynamic {
+  self::foo(4, 5);
+  self::foo(6, 7);
+  self::loop(<dynamic>["dfg"]);
+}
diff --git a/pkg/front_end/testcases/general/arrow_function.dart.weak.modular.expect b/pkg/front_end/testcases/general/arrow_function.dart.weak.modular.expect
new file mode 100644
index 0000000..964b0b4
--- /dev/null
+++ b/pkg/front_end/testcases/general/arrow_function.dart.weak.modular.expect
@@ -0,0 +1,6 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main<T extends core::Object* = dynamic>() → dynamic
+  return () → core::Type* => self::main::T*;
diff --git a/pkg/front_end/testcases/general/assign_to_initializing_formal.dart.weak.modular.expect b/pkg/front_end/testcases/general/assign_to_initializing_formal.dart.weak.modular.expect
new file mode 100644
index 0000000..49729e1
--- /dev/null
+++ b/pkg/front_end/testcases/general/assign_to_initializing_formal.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/assign_to_initializing_formal.dart:13:11: Error: Can't assign to the final variable 'x'.
+//           x = 3;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "package:expect/expect.dart";
+
+class A extends core::Object {
+  field dynamic x;
+  field dynamic y;
+  constructor •(dynamic x) → self::A*
+    : self::A::x = x, self::A::y = () → Null {
+      invalid-expression "pkg/front_end/testcases/general/assign_to_initializing_formal.dart:13:11: Error: Can't assign to the final variable 'x'.
+          x = 3;
+          ^";
+    }, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/async_function.dart.weak.modular.expect b/pkg/front_end/testcases/general/async_function.dart.weak.modular.expect
new file mode 100644
index 0000000..4a640a9
--- /dev/null
+++ b/pkg/front_end/testcases/general/async_function.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "dart:async";
+
+static field core::List<core::String*>* stringList = <core::String*>["bar"];
+static method asyncString() → asy::Future<core::String*>* async {
+  return "foo";
+}
+static method asyncString2() → asy::Future<core::String*>* async {
+  return self::asyncString();
+}
+static method syncStarString() → core::Iterable<core::String*>* sync* {
+  yield "foo";
+  yield* self::syncStarString2();
+  yield* self::stringList;
+}
+static method syncStarString2() → core::Iterable<core::String*>* sync* {
+  yield "foo";
+}
+static method asyncStarString() → asy::Stream<core::String*>* async* {
+  yield "foo";
+  yield* self::asyncStarString2();
+  yield await self::asyncString();
+}
+static method asyncStarString2() → asy::Stream<core::String*>* async* {
+  yield "bar";
+}
+static method main() → dynamic async {
+  core::String* str = await self::asyncString();
+}
diff --git a/pkg/front_end/testcases/general/async_method_with_invalid_type.dart.weak.modular.expect b/pkg/front_end/testcases/general/async_method_with_invalid_type.dart.weak.modular.expect
new file mode 100644
index 0000000..5472a32
--- /dev/null
+++ b/pkg/front_end/testcases/general/async_method_with_invalid_type.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/async_method_with_invalid_type.dart:8:3: Error: 'Bar' isn't a type.
+//   Bar x;
+//   ^^^
+//
+import self as self;
+
+static method foo() → dynamic async {
+  invalid-type x;
+  for (dynamic y in x{<invalid>}.z) {
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/async_nested.dart.weak.modular.expect b/pkg/front_end/testcases/general/async_nested.dart.weak.modular.expect
new file mode 100644
index 0000000..48269f1
--- /dev/null
+++ b/pkg/front_end/testcases/general/async_nested.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class Node extends core::Object {
+  final field core::List<self::Node*>* nested;
+  final field core::String* name;
+  constructor •(core::String* name, [core::List<self::Node*>* nested = #C1]) → self::Node*
+    : self::Node::name = name, self::Node::nested = nested, super core::Object::•() {}
+  method toString() → core::String*
+    return "<${this.{self::Node::name}{core::String*}}:[${let final core::List<self::Node*>* #t1 = this.{self::Node::nested}{core::List<self::Node*>*} in #t1 == null ?{core::String*} null : #t1.{core::Iterable::join}(", "){([core::String*]) →* core::String*}}]>";
+  method toSimpleString() → dynamic {
+    core::Iterable<dynamic>* tmp = let final core::List<self::Node*>* #t2 = this.{self::Node::nested}{core::List<self::Node*>*} in #t2 == null ?{core::Iterable<dynamic>*} null : #t2.{core::Iterable::map}<dynamic>((self::Node* child) → dynamic => child.{self::Node::toSimpleString}(){() →* dynamic}){((self::Node*) →* dynamic) →* core::Iterable<dynamic>*};
+    return "${this.{self::Node::name}{core::String*}} ${let final core::Iterable<dynamic>* #t3 = tmp in #t3 == null ?{core::String*} null : #t3.{core::Iterable::join}(" "){([core::String*]) →* core::String*}}".{core::String::trim}(){() →* core::String*};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void async {
+  core::String* expected = "1 2 3 4 5 6 7 8 9 10";
+  self::Node* node = new self::Node::•("1", <self::Node*>[new self::Node::•("2", <self::Node*>[]), await asy::Future::value<self::Node*>(new self::Node::•("3", <self::Node*>[await asy::Future::value<self::Node*>(new self::Node::•("4", <self::Node*>[new self::Node::•("5", <self::Node*>[await asy::Future::value<self::Node*>(new self::Node::•("6", <self::Node*>[await asy::Future::value<self::Node*>(new self::Node::•("7", <self::Node*>[]))])), await asy::Future::value<self::Node*>(new self::Node::•("8", <self::Node*>[])), await asy::Future::value<self::Node*>(new self::Node::•("9", <self::Node*>[]))])]))])), await asy::Future::value<self::Node*>(new self::Node::•("10", <self::Node*>[]))]);
+  core::String* actual = node.{self::Node::toSimpleString}(){() →* dynamic} as{TypeError,ForDynamic} core::String*;
+  core::print(actual);
+  if(!(actual =={core::String::==}{(core::Object*) →* core::bool*} expected)) {
+    throw "Expected '${expected}' but got '${actual}'";
+  }
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/await.dart.weak.modular.expect b/pkg/front_end/testcases/general/await.dart.weak.modular.expect
new file mode 100644
index 0000000..5b1be33
--- /dev/null
+++ b/pkg/front_end/testcases/general/await.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic async {
+  core::print(await "Hello, World!");
+}
diff --git a/pkg/front_end/testcases/general/await_complex.dart.weak.modular.expect b/pkg/front_end/testcases/general/await_complex.dart.weak.modular.expect
new file mode 100644
index 0000000..20324c7
--- /dev/null
+++ b/pkg/front_end/testcases/general/await_complex.dart.weak.modular.expect
@@ -0,0 +1,260 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class C extends core::Object {
+  static field core::int* staticField = 1;
+  field core::int* field = 1;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  static get staticGetter() → core::int*
+    return self::C::staticField;
+  static set staticSetter(dynamic val) → void {
+    self::C::staticField = val as{TypeError,ForDynamic} core::int*;
+  }
+  static method staticFoo(core::int* param) → core::int*
+    return param;
+  get getter() → core::int*
+    return this.{self::C::field}{core::int*};
+  set setter(dynamic val) → void {
+    this.{self::C::field} = val as{TypeError,ForDynamic} core::int*;
+  }
+  method foo(core::int* param) → core::int*
+    return param;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* globalVariable = 1;
+static final field core::bool* assertStatementsEnabled = (() → core::bool* {
+  try {
+    assert(false);
+    return false;
+  }
+  on dynamic catch(final dynamic _) {
+    return true;
+  }
+})(){() →* core::bool*};
+static method topLevelFoo(core::int* param) → core::int*
+  return 1;
+static get topLevelGetter() → core::int*
+  return self::globalVariable;
+static set topLevelSetter(dynamic val) → void {
+  self::globalVariable = val as{TypeError,ForDynamic} core::int*;
+}
+static method dummy() → dynamic
+  return 1;
+static method staticMembers() → dynamic async {
+  core::num* a = self::C::staticField.{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(2, a);
+  core::num* f = (self::C::staticField = 1).{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(2, f);
+  core::num* b = self::C::staticGetter.{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(2, b);
+  core::num* c = (self::C::staticSetter = 1).{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(2, c);
+  core::num* d = self::C::staticFoo(2).{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(3, d);
+  core::num* e = self::C::staticField.{core::num::+}(self::C::staticGetter){(core::num*) →* core::int*}.{core::num::+}(self::C::staticSetter = 1){(core::num*) →* core::int*}.{core::num::+}(self::C::staticFoo(1)){(core::num*) →* core::int*}.{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(5, e);
+}
+static method topLevelMembers() → dynamic async {
+  core::num* a = self::globalVariable.{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(2, a);
+  core::num* b = self::topLevelGetter.{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(2, b);
+  core::num* c = (self::topLevelSetter = 1).{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(2, c);
+  core::num* d = self::topLevelFoo(1).{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(2, d);
+  core::num* e = self::globalVariable.{core::num::+}(self::topLevelGetter){(core::num*) →* core::int*}.{core::num::+}(self::topLevelSetter = 1){(core::num*) →* core::int*}.{core::num::+}(self::topLevelFoo(1)){(core::num*) →* core::int*}.{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(5, e);
+}
+static method instanceMembers() → dynamic async {
+  self::C* inst = new self::C::•();
+  core::num* a = inst.{self::C::field}{core::int*}.{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(2, a);
+  core::num* b = inst.{self::C::getter}{core::int*}.{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(2, b);
+  core::num* c = (inst.{self::C::setter} = 1).{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(2, c);
+  core::num* d = inst.{self::C::foo}(1){(core::int*) →* core::int*}.{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(2, d);
+  core::num* e = inst.{self::C::field}{core::int*}.{core::num::+}(inst.{self::C::getter}{core::int*}){(core::num*) →* core::int*}.{core::num::+}(inst.{self::C::setter} = 1){(core::num*) →* core::int*}.{core::num::+}(inst.{self::C::foo}(1){(core::int*) →* core::int*}){(core::num*) →* core::int*}.{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(5, e);
+}
+static method others() → dynamic async {
+  core::String* a = "${self::globalVariable} ${await self::dummy()} ".{core::String::+}(await "someString"){(core::String*) →* core::String*};
+  self::expect("1 1 someString", a);
+  self::C* c = new self::C::•();
+  core::num* d = c.{self::C::field}{core::int*}.{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  core::int* cnt = 2;
+  core::List<core::int*>* b = <core::int*>[1, 2, 3];
+  b.{core::List::[]=}(cnt, await self::dummy() as{TypeError,ForDynamic} core::int*){(core::int*, core::int*) →* void};
+  self::expect(1, b.{core::List::[]}(cnt){(core::int*) →* core::int*});
+  core::num* e = b.{core::List::[]}(0){(core::int*) →* core::int*}.{core::num::+}(await self::dummy() as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  self::expect(2, e);
+}
+static method conditionals() → dynamic async {
+  core::bool* a = false;
+  core::bool* b = true;
+  core::bool* c = a || b || await self::dummy() as{TypeError,ForDynamic} core::bool*;
+  self::expect(true, c);
+  dynamic d = a || b ?{dynamic} a : await self::dummy();
+  self::expect(false, d);
+  dynamic e = a is core::int* ?{dynamic} await self::dummy() : 2;
+  self::expect(2, e);
+  try {
+    dynamic f = a is core::int* ?{dynamic} await self::dummy() : 2;
+  }
+  on dynamic catch(final dynamic e) {
+  }
+}
+static method asserts() → dynamic async {
+  for (final core::Function* #t1 in <core::Function*>[#C1, #C2]) {
+    final <T extends core::Object* = dynamic>(T*) →* FutureOr<T*>* func = #t1 as{TypeError} <T extends core::Object* = dynamic>(T*) →* FutureOr<T*>*;
+    assert(await func<core::bool*>(true){(core::bool*) →* FutureOr<core::bool*>*});
+    assert(self::id<core::bool*>(true) as{TypeError} core::bool*, await func<core::String*>("message"){(core::String*) →* FutureOr<core::String*>*});
+    assert(await func<core::bool*>(true){(core::bool*) →* FutureOr<core::bool*>*}, await func<core::String*>("message"){(core::String*) →* FutureOr<core::String*>*});
+    try {
+      assert(await func<core::bool*>(false){(core::bool*) →* FutureOr<core::bool*>*}, await func<core::String*>("message"){(core::String*) →* FutureOr<core::String*>*});
+      if(self::assertStatementsEnabled)
+        throw "Didn't throw";
+    }
+    on core::AssertionError* catch(final core::AssertionError* e) {
+      self::expect("message", e.{core::AssertionError::message}{core::Object*});
+    }
+  }
+}
+static method controlFlow() → dynamic async {
+  for (final core::Function* #t2 in <core::Function*>[#C1, #C2]) {
+    final <T extends core::Object* = dynamic>(T*) →* FutureOr<T*>* func = #t2 as{TypeError} <T extends core::Object* = dynamic>(T*) →* FutureOr<T*>*;
+    core::int* c = 0;
+    for (core::int* i = await func<core::int*>(0){(core::int*) →* FutureOr<core::int*>*}; await func<core::bool*>(i.{core::num::<}(5){(core::num*) →* core::bool*}){(core::bool*) →* FutureOr<core::bool*>*}; await func<core::int*>(let final core::int* #t3 = i in let final core::int* #t4 = i = #t3.{core::num::+}(1){(core::num*) →* core::int*} in #t3){(core::int*) →* FutureOr<core::int*>*}) {
+      c = c.{core::num::+}(1){(core::num*) →* core::int*};
+    }
+    self::expect(5, c);
+    c = 0;
+    while (await func<core::bool*>(c.{core::num::<}(5){(core::num*) →* core::bool*}){(core::bool*) →* FutureOr<core::bool*>*})
+      c = c.{core::num::+}(1){(core::num*) →* core::int*};
+    self::expect(5, c);
+    c = 0;
+    do {
+      c = c.{core::num::+}(1){(core::num*) →* core::int*};
+    }
+    while (await func<core::bool*>(c.{core::num::<}(5){(core::num*) →* core::bool*}){(core::bool*) →* FutureOr<core::bool*>*})
+    self::expect(5, c);
+    if(await func<core::bool*>(c =={core::num::==}{(core::Object*) →* core::bool*} 5){(core::bool*) →* FutureOr<core::bool*>*}) {
+      self::expect(5, c);
+    }
+    else {
+      throw "unreachable";
+    }
+    try {
+      throw await func<core::String*>("string"){(core::String*) →* FutureOr<core::String*>*};
+    }
+    on core::String* catch(no-exception-var) {
+    }
+    try {
+      await throw "string";
+    }
+    on core::String* catch(no-exception-var) {
+    }
+    try
+      try {
+        try
+          try {
+            throw "string";
+          }
+          on dynamic catch(final dynamic e) {
+            self::expect("string", e);
+            self::expect(0, await func<core::int*>(0){(core::int*) →* FutureOr<core::int*>*});
+            rethrow;
+          }
+        finally {
+          self::expect(0, await func<core::int*>(0){(core::int*) →* FutureOr<core::int*>*});
+        }
+      }
+      on dynamic catch(final dynamic e) {
+        self::expect(0, await func<core::int*>(0){(core::int*) →* FutureOr<core::int*>*});
+        self::expect("string", e);
+      }
+    finally {
+      self::expect(0, await func<core::int*>(0){(core::int*) →* FutureOr<core::int*>*});
+    }
+    #L1:
+    switch(await func<core::int*>(2){(core::int*) →* FutureOr<core::int*>*}) {
+      #L2:
+      case #C3:
+        {
+          break #L1;
+        }
+      #L3:
+      default:
+        {
+          throw "unreachable";
+        }
+    }
+    self::expect(42, await(() → asy::Future<dynamic>* async {
+      return await func<dynamic>(42){(dynamic) →* FutureOr<dynamic>*};
+    })(){() →* asy::Future<dynamic>*});
+    self::expect(42, await(() → asy::Future<dynamic>* async {
+      return func<dynamic>(42){(dynamic) →* FutureOr<dynamic>*};
+    })(){() →* asy::Future<dynamic>*});
+    function testStream1() → asy::Stream<core::int*>* async* {
+      yield await func<core::int*>(42){(core::int*) →* FutureOr<core::int*>*};
+    }
+    self::expectList(<dynamic>[42], await testStream1(){() →* asy::Stream<core::int*>*}.{asy::Stream::toList}(){() →* asy::Future<core::List<core::int*>*>*});
+    function testStream2() → asy::Stream<core::int*>* async* {
+      yield* await func<asy::Stream<core::int*>*>(self::intStream()){(asy::Stream<core::int*>*) →* FutureOr<asy::Stream<core::int*>*>*};
+    }
+    self::expectList(<dynamic>[42], await testStream2(){() →* asy::Stream<core::int*>*}.{asy::Stream::toList}(){() →* asy::Future<core::List<core::int*>*>*});
+  }
+}
+static method future<T extends core::Object* = dynamic>(self::future::T* value) → FutureOr<self::future::T*>* async 
+  return value;
+static method id<T extends core::Object* = dynamic>(self::id::T* value) → FutureOr<self::id::T*>*
+  return value;
+static method intStream() → asy::Stream<core::int*>* async* {
+  yield 42;
+}
+static method main() → dynamic async {
+  for (core::int* i = 0; i.{core::num::<}(11){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+    await self::staticMembers();
+    await self::topLevelMembers();
+    await self::instanceMembers();
+    await self::conditionals();
+    await self::others();
+    await self::asserts();
+    await self::controlFlow();
+  }
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method expectList(core::List<dynamic>* expected, core::List<dynamic>* actual) → dynamic {
+  if(!(expected.{core::List::length}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} actual.{core::List::length}{core::int*})) {
+    throw "Expected ${expected}, actual ${actual}";
+  }
+  for (core::int* i = 0; i.{core::num::<}(expected.{core::List::length}{core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+    self::expect(expected.{core::List::[]}(i){(core::int*) →* dynamic}, actual.{core::List::[]}(i){(core::int*) →* dynamic});
+  }
+}
+
+constants  {
+  #C1 = static-tearoff self::id
+  #C2 = static-tearoff self::future
+  #C3 = 2
+}
diff --git a/pkg/front_end/testcases/general/await_in_cascade.dart.weak.modular.expect b/pkg/front_end/testcases/general/await_in_cascade.dart.weak.modular.expect
new file mode 100644
index 0000000..8a57698
--- /dev/null
+++ b/pkg/front_end/testcases/general/await_in_cascade.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method m() → asy::Future<core::List<core::int*>*>* async 
+    return let final core::List<core::int*>* #t1 = <core::int*>[] in block {
+      #t1.{core::List::add}(await this.{self::C::_m}(){() →* asy::Future<core::int*>*}){(core::int*) →* void};
+    } =>#t1;
+  method _m() → asy::Future<core::int*>* async 
+    return 42;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic async {
+  self::expect(42, (await new self::C::•().{self::C::m}(){() →* asy::Future<core::List<core::int*>*>*}).{core::Iterable::first}{core::int*});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/general/await_in_non_async.dart.weak.modular.expect b/pkg/front_end/testcases/general/await_in_non_async.dart.weak.modular.expect
new file mode 100644
index 0000000..aa3b0e2
--- /dev/null
+++ b/pkg/front_end/testcases/general/await_in_non_async.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/await_in_non_async.dart:11:3: Error: 'await' can only be used in 'async' or 'async*' methods.
+//   await foo();
+//   ^^^^^
+//
+import self as self;
+
+static method main() → dynamic {
+  self::foo();
+}
+static method foo() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/await_in_non_async.dart:11:3: Error: 'await' can only be used in 'async' or 'async*' methods.
+  await foo();
+  ^^^^^";
+}
diff --git a/pkg/front_end/testcases/general/bad_setter_abstract.dart.weak.modular.expect b/pkg/front_end/testcases/general/bad_setter_abstract.dart.weak.modular.expect
new file mode 100644
index 0000000..839e066
--- /dev/null
+++ b/pkg/front_end/testcases/general/bad_setter_abstract.dart.weak.modular.expect
@@ -0,0 +1,179 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/bad_setter_abstract.dart:5:8: Error: Expected a function body or '=>'.
+// Try adding {}.
+// set b();
+//        ^
+//
+// pkg/front_end/testcases/general/bad_setter_abstract.dart:7:12: Error: Expected a function body or '=>'.
+// Try adding {}.
+// set c(x, y);
+//            ^
+//
+// pkg/front_end/testcases/general/bad_setter_abstract.dart:5:6: Error: A setter should have exactly one formal parameter.
+// set b();
+//      ^
+//
+// pkg/front_end/testcases/general/bad_setter_abstract.dart:7:6: Error: A setter should have exactly one formal parameter.
+// set c(x, y);
+//      ^
+//
+// pkg/front_end/testcases/general/bad_setter_abstract.dart:10:8: Error: A setter should have exactly one formal parameter.
+//   set a();
+//        ^
+//
+// pkg/front_end/testcases/general/bad_setter_abstract.dart:11:8: Error: A setter should have exactly one formal parameter.
+//   set d(x, y);
+//        ^
+//
+// pkg/front_end/testcases/general/bad_setter_abstract.dart:15:8: Error: A setter should have exactly one formal parameter.
+//   set a();
+//        ^
+//
+// pkg/front_end/testcases/general/bad_setter_abstract.dart:16:8: Error: A setter should have exactly one formal parameter.
+//   set d(x, y);
+//        ^
+//
+// pkg/front_end/testcases/general/bad_setter_abstract.dart:66:9: Error: The class 'B' is abstract and can't be instantiated.
+//     new B();
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  set a(dynamic #synthetic) → void {
+    invalid-expression "pkg/front_end/testcases/general/bad_setter_abstract.dart:10:8: Error: A setter should have exactly one formal parameter.
+  set a();
+       ^";
+    ;
+  }
+  set d(dynamic #synthetic) → void {
+    invalid-expression "pkg/front_end/testcases/general/bad_setter_abstract.dart:11:8: Error: A setter should have exactly one formal parameter.
+  set d(x, y);
+       ^";
+    {
+      dynamic x;
+      dynamic y;
+      ;
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  set a(dynamic #synthetic) → void {
+    invalid-expression "pkg/front_end/testcases/general/bad_setter_abstract.dart:15:8: Error: A setter should have exactly one formal parameter.
+  set a();
+       ^";
+    ;
+  }
+  set d(dynamic #synthetic) → void {
+    invalid-expression "pkg/front_end/testcases/general/bad_setter_abstract.dart:16:8: Error: A setter should have exactly one formal parameter.
+  set d(x, y);
+       ^";
+    {
+      dynamic x;
+      dynamic y;
+      ;
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static set b(dynamic #synthetic) → void {
+  invalid-expression "pkg/front_end/testcases/general/bad_setter_abstract.dart:5:6: Error: A setter should have exactly one formal parameter.
+set b();
+     ^";
+  ;
+}
+static set c(dynamic #synthetic) → void {
+  invalid-expression "pkg/front_end/testcases/general/bad_setter_abstract.dart:7:6: Error: A setter should have exactly one formal parameter.
+set c(x, y);
+     ^";
+  {
+    dynamic x;
+    dynamic y;
+    ;
+  }
+}
+static method main() → dynamic {
+  core::bool* threw;
+  try {
+    threw = true;
+    new self::A::•().{self::A::a} = null;
+    threw = false;
+  }
+  on dynamic catch(final dynamic e) {
+  }
+  if(!threw) {
+    throw "Expected an error above.";
+  }
+  try {
+    threw = true;
+    new self::A::•().{self::A::d} = null;
+    threw = false;
+  }
+  on dynamic catch(final dynamic e) {
+  }
+  if(!threw) {
+    throw "Expected an error above.";
+  }
+  try {
+    threw = true;
+    self::b = null;
+    threw = false;
+  }
+  on dynamic catch(final dynamic e) {
+  }
+  if(!threw) {
+    throw "Expected an error above.";
+  }
+  if(!threw) {
+    throw "Expected an error above.";
+  }
+  try {
+    threw = true;
+    self::c = null;
+    threw = false;
+  }
+  on dynamic catch(final dynamic e) {
+  }
+  if(!threw) {
+    throw "Expected an error above.";
+  }
+  try {
+    threw = true;
+    throw new core::AbstractClassInstantiationError::•("B");
+    threw = false;
+  }
+  on core::AbstractClassInstantiationError* catch(final core::AbstractClassInstantiationError* _) {
+  }
+  if(!threw) {
+    throw "Expected an error above.";
+  }
+}
diff --git a/pkg/front_end/testcases/general/bad_store.dart.weak.modular.expect b/pkg/front_end/testcases/general/bad_store.dart.weak.modular.expect
new file mode 100644
index 0000000..f25c04b
--- /dev/null
+++ b/pkg/front_end/testcases/general/bad_store.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  field dynamic field = null;
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method identity(dynamic x) → dynamic
+  return x;
+static method use(dynamic x) → void {}
+static method main(core::List<core::String*>* args) → dynamic {
+  dynamic foo = self::identity(new self::Foo::•());
+  if(args.{core::List::length}{core::int*}.{core::num::>}(1){(core::num*) →* core::bool*}) {
+    foo{dynamic}.field = "string";
+    dynamic first = foo{dynamic}.field;
+    self::use(first);
+    foo{dynamic}.noField = "string";
+    dynamic second = foo{dynamic}.noField;
+    self::use(second);
+  }
+}
diff --git a/pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart.weak.modular.expect b/pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart.weak.modular.expect
new file mode 100644
index 0000000..1e435e2
--- /dev/null
+++ b/pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart.weak.modular.expect
@@ -0,0 +1,633 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:13:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class B<T> extends A<Function(T)> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:15:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class Bc<T> extends A<ContravariantUse<T>> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:17:7: Error: Can't use implicitly 'out' variable 'T' in an 'inout' position in supertype 'A'.
+// class Bi<T> extends A<InvariantUse<T>> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:19:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class C<T> implements A<Function(T)> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:21:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class Cc<T> implements A<ContravariantUse<T>> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:23:7: Error: Can't use implicitly 'out' variable 'T' in an 'inout' position in supertype 'A'.
+// class Ci<T> implements A<InvariantUse<T>> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:25:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class D<T> = Object with A<Function(T)>;
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:27:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class Dc<T> = Object with A<ContravariantUse<T>>;
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:29:7: Error: Can't use implicitly 'out' variable 'T' in an 'inout' position in supertype 'A'.
+// class Di<T> = Object with A<InvariantUse<T>>;
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:31:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class E<T> = A<Function(T)> with Empty;
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:33:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class Ec<T> = A<ContravariantUse<T>> with Empty;
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:35:7: Error: Can't use implicitly 'out' variable 'T' in an 'inout' position in supertype 'A'.
+// class Ei<T> = A<InvariantUse<T>> with Empty;
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:37:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class F<T> extends Object with A<Function(T)> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:39:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class Fc<T> extends Object with A<ContravariantUse<T>> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:41:7: Error: Can't use implicitly 'out' variable 'T' in an 'inout' position in supertype 'A'.
+// class Fi<T> extends Object with A<InvariantUse<T>> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:43:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class G<T> extends A<Function(T)> with Empty {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:45:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class Gc<T> extends A<ContravariantUse<T>> with Empty {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:47:7: Error: Can't use implicitly 'out' variable 'T' in an 'inout' position in supertype 'A'.
+// class Gi<T> extends A<InvariantUse<T>> with Empty {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:57:7: Error: Can't use implicitly 'out' variable 'T' in an 'inout' position in supertype 'A'.
+// class Hii<T> extends A<InvariantUse<InvariantUse<T>>> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:71:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class Jfff<T> extends A<Function(Function(Function(T)))> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:73:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class Jffc<T> extends A<Function(Function(ContravariantUse<T>))> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:75:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class Jfcf<T> extends A<Function(ContravariantUse<Function(T)>)> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:77:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class Jfcc<T> extends A<Function(ContravariantUse<ContravariantUse<T>>)> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:79:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class Jcff<T> extends A<ContravariantUse<Function(Function(T))>> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:81:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class Jcfc<T> extends A<ContravariantUse<Function(ContravariantUse<T>)>> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:83:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class Jccf<T> extends A<ContravariantUse<ContravariantUse<Function(T)>>> {}
+//       ^
+//
+// pkg/front_end/testcases/general/bad_type_variable_uses_in_supertypes.dart:85:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class Jccc<T>
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef ContravariantUse<contravariant T extends core::Object* = dynamic> = (T*) →* dynamic;
+typedef InvariantUse<invariant T extends core::Object* = dynamic> = (T*) →* T*;
+class Empty extends core::Object {
+  synthetic constructor •() → self::Empty*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bc<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Bc<self::Bc::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bi<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Bi<self::Bi::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Cc<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Cc<self::Cc::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Ci<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Ci<self::Ci::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<T extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Dc<T extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Dc<self::Dc::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Di<T extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Di<self::Di::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E<T extends core::Object* = dynamic> = core::Object with self::Empty {
+  synthetic constructor •() → self::E<self::E::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Ec<T extends core::Object* = dynamic> = core::Object with self::Empty {
+  synthetic constructor •() → self::Ec<self::Ec::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Ei<T extends core::Object* = dynamic> = core::Object with self::Empty {
+  synthetic constructor •() → self::Ei<self::Ei::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _F&Object&A<T extends core::Object* = dynamic> extends core::Object /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_F&Object&A<self::_F&Object&A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F<T extends core::Object* = dynamic> extends self::_F&Object&A<self::F::T*> {
+  synthetic constructor •() → self::F<self::F::T*>*
+    : super self::_F&Object&A::•()
+    ;
+}
+abstract class _Fc&Object&A<T extends core::Object* = dynamic> extends core::Object /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Fc&Object&A<self::_Fc&Object&A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Fc<T extends core::Object* = dynamic> extends self::_Fc&Object&A<self::Fc::T*> {
+  synthetic constructor •() → self::Fc<self::Fc::T*>*
+    : super self::_Fc&Object&A::•()
+    ;
+}
+abstract class _Fi&Object&A<T extends core::Object* = dynamic> extends core::Object /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Fi&Object&A<self::_Fi&Object&A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Fi<T extends core::Object* = dynamic> extends self::_Fi&Object&A<self::Fi::T*> {
+  synthetic constructor •() → self::Fi<self::Fi::T*>*
+    : super self::_Fi&Object&A::•()
+    ;
+}
+abstract class _G&A&Empty<T extends core::Object* = dynamic> = core::Object with self::Empty /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_G&A&Empty<self::_G&A&Empty::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class G<T extends core::Object* = dynamic> extends self::_G&A&Empty<self::G::T*> {
+  synthetic constructor •() → self::G<self::G::T*>*
+    : super self::_G&A&Empty::•()
+    ;
+}
+abstract class _Gc&A&Empty<T extends core::Object* = dynamic> = core::Object with self::Empty /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Gc&A&Empty<self::_Gc&A&Empty::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Gc<T extends core::Object* = dynamic> extends self::_Gc&A&Empty<self::Gc::T*> {
+  synthetic constructor •() → self::Gc<self::Gc::T*>*
+    : super self::_Gc&A&Empty::•()
+    ;
+}
+abstract class _Gi&A&Empty<T extends core::Object* = dynamic> = core::Object with self::Empty /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Gi&A&Empty<self::_Gi&A&Empty::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Gi<T extends core::Object* = dynamic> extends self::_Gi&A&Empty<self::Gi::T*> {
+  synthetic constructor •() → self::Gi<self::Gi::T*>*
+    : super self::_Gi&A&Empty::•()
+    ;
+}
+class Hff<T extends core::Object* = dynamic> extends self::A<((self::Hff::T*) →* dynamic) →* dynamic> {
+  synthetic constructor •() → self::Hff<self::Hff::T*>*
+    : super self::A::•()
+    ;
+}
+class Hfc<T extends core::Object* = dynamic> extends self::A<((self::Hfc::T*) →* dynamic) →* dynamic> {
+  synthetic constructor •() → self::Hfc<self::Hfc::T*>*
+    : super self::A::•()
+    ;
+}
+class Hcf<T extends core::Object* = dynamic> extends self::A<((self::Hcf::T*) →* dynamic) →* dynamic> {
+  synthetic constructor •() → self::Hcf<self::Hcf::T*>*
+    : super self::A::•()
+    ;
+}
+class Hcc<T extends core::Object* = dynamic> extends self::A<((self::Hcc::T*) →* dynamic) →* dynamic> {
+  synthetic constructor •() → self::Hcc<self::Hcc::T*>*
+    : super self::A::•()
+    ;
+}
+class Hii<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Hii<self::Hii::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Iafc<T extends core::Object* = dynamic> extends self::A<self::A<((self::Iafc::T*) →* dynamic) →* dynamic>*> {
+  synthetic constructor •() → self::Iafc<self::Iafc::T*>*
+    : super self::A::•()
+    ;
+}
+class Iacf<T extends core::Object* = dynamic> extends self::A<self::A<((self::Iacf::T*) →* dynamic) →* dynamic>*> {
+  synthetic constructor •() → self::Iacf<self::Iacf::T*>*
+    : super self::A::•()
+    ;
+}
+class Ifac<T extends core::Object* = dynamic> extends self::A<(self::A<(self::Ifac::T*) →* dynamic>*) →* dynamic> {
+  synthetic constructor •() → self::Ifac<self::Ifac::T*>*
+    : super self::A::•()
+    ;
+}
+class Ifca<T extends core::Object* = dynamic> extends self::A<((self::A<self::Ifca::T*>*) →* dynamic) →* dynamic> {
+  synthetic constructor •() → self::Ifca<self::Ifca::T*>*
+    : super self::A::•()
+    ;
+}
+class Icaf<T extends core::Object* = dynamic> extends self::A<(self::A<(self::Icaf::T*) →* dynamic>*) →* dynamic> {
+  synthetic constructor •() → self::Icaf<self::Icaf::T*>*
+    : super self::A::•()
+    ;
+}
+class Icfa<T extends core::Object* = dynamic> extends self::A<((self::A<self::Icfa::T*>*) →* dynamic) →* dynamic> {
+  synthetic constructor •() → self::Icfa<self::Icfa::T*>*
+    : super self::A::•()
+    ;
+}
+class Jfff<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Jfff<self::Jfff::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Jffc<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Jffc<self::Jffc::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Jfcf<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Jfcf<self::Jfcf::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Jfcc<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Jfcc<self::Jfcc::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Jcff<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Jcff<self::Jcff::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Jcfc<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Jcfc<self::Jcfc::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Jccf<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Jccf<self::Jccf::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Jccc<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Jccc<self::Jccc::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/bounded_implicit_instantiation.dart.weak.modular.expect b/pkg/front_end/testcases/general/bounded_implicit_instantiation.dart.weak.modular.expect
new file mode 100644
index 0000000..2b37371
--- /dev/null
+++ b/pkg/front_end/testcases/general/bounded_implicit_instantiation.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/bounded_implicit_instantiation.dart:7:22: Error: The argument type 'String' can't be assigned to the parameter type 'Never'.
+//   String a = bounded('');
+//                      ^
+//
+// pkg/front_end/testcases/general/bounded_implicit_instantiation.dart:8:21: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'bounded'.
+// Try changing type arguments so that they conform to the bounds.
+//   String b = bounded<String>('');
+//                     ^
+//
+// pkg/front_end/testcases/general/bounded_implicit_instantiation.dart:9:31: Error: Inferred type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'X Function<X extends num>(X)'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   String Function(String) c = bounded;
+//                               ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+static method test() → dynamic {
+  function bounded<X extends core::num>(X x) → X
+    return x;
+  core::String a = let final Never #t1 = bounded<Never>(invalid-expression "pkg/front_end/testcases/general/bounded_implicit_instantiation.dart:7:22: Error: The argument type 'String' can't be assigned to the parameter type 'Never'.
+  String a = bounded('');
+                     ^" in "" as{TypeError,ForNonNullableByDefault} Never){(Never) → Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  core::String b = bounded<core::String>(""){(core::String) → core::String};
+  (core::String) → core::String c = bounded<core::String>;
+  core::String d = c(""){(core::String) → core::String};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/bounds_check_depends_on_inference.dart.weak.modular.expect b/pkg/front_end/testcases/general/bounds_check_depends_on_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..228018a
--- /dev/null
+++ b/pkg/front_end/testcases/general/bounds_check_depends_on_inference.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  method bar<covariant-by-class Y extends self::A::X*>() → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  static method foo<Y extends core::Object*>() → self::A<self::B::foo::Y*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method baz() → dynamic {
+  self::B::foo<core::Object*>().{self::A::bar}<core::String*>(){() →* dynamic};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/bounds_check_in_typedef.dart.weak.modular.expect b/pkg/front_end/testcases/general/bounds_check_in_typedef.dart.weak.modular.expect
new file mode 100644
index 0000000..01f1570
--- /dev/null
+++ b/pkg/front_end/testcases/general/bounds_check_in_typedef.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/bounds_check_in_typedef.dart:7:40: Error: Type argument 'Y' doesn't conform to the bound 'String' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+// typedef F = Function<Z extends A<Y>>() Function<Y extends num>();
+//                                        ^
+// pkg/front_end/testcases/general/bounds_check_in_typedef.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends String> {}
+//         ^
+//
+// pkg/front_end/testcases/general/bounds_check_in_typedef.dart:8:18: Error: Type argument 'Y' doesn't conform to the bound 'String' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+// typedef G = void Function<Y extends num>(Function<Z extends A<Y>>());
+//                  ^
+// pkg/front_end/testcases/general/bounds_check_in_typedef.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends String> {}
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F = <Y extends core::num* = dynamic>() →* <Z extends self::A<Y*>* = dynamic>() →* dynamic;
+typedef G = <Y extends core::num* = dynamic>(<Z extends self::A<Y*>* = dynamic>() →* dynamic) →* void;
+class A<X extends core::String*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/bug21938.dart.weak.modular.expect b/pkg/front_end/testcases/general/bug21938.dart.weak.modular.expect
new file mode 100644
index 0000000..d46ee72
--- /dev/null
+++ b/pkg/front_end/testcases/general/bug21938.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/bug21938.dart:8:4: Error: The method 'call' isn't defined for the class 'Object'.
+//  - 'Object' is from 'dart:core'.
+// Try correcting the name to the name of an existing method, or defining a method named 'call'.
+//   x();
+//    ^
+//
+// pkg/front_end/testcases/general/bug21938.dart:9:4: Error: The method 'call' isn't defined for the class 'Object'.
+//  - 'Object' is from 'dart:core'.
+// Try correcting the name to the name of an existing method, or defining a method named 'call'.
+//   x(3);
+//    ^
+//
+// pkg/front_end/testcases/general/bug21938.dart:11:5: Error: The method 'call' isn't defined for the class 'Object'.
+//  - 'Object' is from 'dart:core'.
+// Try correcting the name to the name of an existing method, or defining a method named 'call'.
+//   x.call();
+//     ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test() → dynamic {
+  core::Object* x;
+  core::Function* f;
+  invalid-expression "pkg/front_end/testcases/general/bug21938.dart:8:4: Error: The method 'call' isn't defined for the class 'Object'.
+ - 'Object' is from 'dart:core'.
+Try correcting the name to the name of an existing method, or defining a method named 'call'.
+  x();
+   ^" in x{<unresolved>}.call();
+  invalid-expression "pkg/front_end/testcases/general/bug21938.dart:9:4: Error: The method 'call' isn't defined for the class 'Object'.
+ - 'Object' is from 'dart:core'.
+Try correcting the name to the name of an existing method, or defining a method named 'call'.
+  x(3);
+   ^" in x{<unresolved>}.call(3);
+  f(5, 2);
+  invalid-expression "pkg/front_end/testcases/general/bug21938.dart:11:5: Error: The method 'call' isn't defined for the class 'Object'.
+ - 'Object' is from 'dart:core'.
+Try correcting the name to the name of an existing method, or defining a method named 'call'.
+  x.call();
+    ^^^^" in x{<unresolved>}.call();
+  f.call;
+  f(5, 2);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/bug30695.dart.weak.modular.expect b/pkg/front_end/testcases/general/bug30695.dart.weak.modular.expect
new file mode 100644
index 0000000..87f32bd
--- /dev/null
+++ b/pkg/front_end/testcases/general/bug30695.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/bug30695.dart:11:3: Error: Can't declare a member that conflicts with an inherited one.
+//   foo() => 42;
+//   ^^^
+// pkg/front_end/testcases/general/bug30695.dart:6:7: Context: This is the inherited member.
+//   var foo = 42;
+//       ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* foo = 42;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  method foo() → dynamic
+    return 42;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/bug31124.dart.weak.modular.expect b/pkg/front_end/testcases/general/bug31124.dart.weak.modular.expect
new file mode 100644
index 0000000..05d5b71
--- /dev/null
+++ b/pkg/front_end/testcases/general/bug31124.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/bug31124.dart:2:22: Error: Expected a function body or '=>'.
+// Try adding {}.
+// var a = () => 'b';a();
+//                      ^
+//
+// pkg/front_end/testcases/general/bug31124.dart:2:19: Error: 'a' is already declared in this scope.
+// var a = () => 'b';a();
+//                   ^
+// pkg/front_end/testcases/general/bug31124.dart:2:5: Context: Previous declaration of 'a'.
+// var a = () => 'b';a();
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field () →* core::String* a;
diff --git a/pkg/front_end/testcases/general/bug32414a.dart.weak.modular.expect b/pkg/front_end/testcases/general/bug32414a.dart.weak.modular.expect
new file mode 100644
index 0000000..8f4896c
--- /dev/null
+++ b/pkg/front_end/testcases/general/bug32414a.dart.weak.modular.expect
@@ -0,0 +1,19 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/bug32414a.dart:10:7: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   b = 42;
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  dynamic a = 5;
+  core::String* b = a.{core::Object::toString}(){() →* core::String*};
+  b = invalid-expression "pkg/front_end/testcases/general/bug32414a.dart:10:7: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  b = 42;
+      ^" in 42 as{TypeError} core::String*;
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/general/bug32414b.dart.weak.modular.expect b/pkg/front_end/testcases/general/bug32414b.dart.weak.modular.expect
new file mode 100644
index 0000000..f09b3fe
--- /dev/null
+++ b/pkg/front_end/testcases/general/bug32414b.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  core::List<dynamic>* l = <dynamic>[1, "hello"];
+  core::List<core::String*>* l2 = l.{core::Iterable::map}<core::String*>((dynamic element) → core::String* => element.{core::Object::toString}(){() →* core::String*}){((dynamic) →* core::String*) →* core::Iterable<core::String*>*}.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<core::String*>*};
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/general/bug32426.dart.weak.modular.expect b/pkg/front_end/testcases/general/bug32426.dart.weak.modular.expect
new file mode 100644
index 0000000..3e48d58
--- /dev/null
+++ b/pkg/front_end/testcases/general/bug32426.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  abstract method call() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object implements self::I {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method call([core::int* x = #C1]) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::I* i = new self::C::•();
+  ([core::int*]) →* void f = (let final self::I* #t1 = i in #t1 == null ?{() →* void} null : #t1.{self::I::call}{() →* void}) as{TypeError} ([core::int*]) →* void;
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/bug32629.dart.weak.modular.expect b/pkg/front_end/testcases/general/bug32629.dart.weak.modular.expect
new file mode 100644
index 0000000..48c5ec01a
--- /dev/null
+++ b/pkg/front_end/testcases/general/bug32629.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/bug32629.dart:16:19: Error: The argument type 'dynamic Function(dynamic, dynamic)' can't be assigned to the parameter type 'String Function(String, dynamic)'.
+//   foo<String>(new A());
+//                   ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef Reducer<invariant S extends core::Object* = dynamic> = (S*, dynamic) →* S*;
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method call(dynamic a, dynamic b) → dynamic {
+    return a;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo<S extends core::Object* = dynamic>((self::foo::S*, dynamic) →* self::foo::S* v) → void {}
+static method test() → void {
+  self::foo<core::String*>(invalid-expression "pkg/front_end/testcases/general/bug32629.dart:16:19: Error: The argument type 'dynamic Function(dynamic, dynamic)' can't be assigned to the parameter type 'String Function(String, dynamic)'.
+  foo<String>(new A());
+                  ^" in (let final self::A* #t1 = new self::A::•() in #t1 == null ?{(dynamic, dynamic) →* dynamic} null : #t1.{self::A::call}{(dynamic, dynamic) →* dynamic}) as{TypeError} (core::String*, dynamic) →* core::String*);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/bug32866.dart.weak.modular.expect b/pkg/front_end/testcases/general/bug32866.dart.weak.modular.expect
new file mode 100644
index 0000000..25924d8
--- /dev/null
+++ b/pkg/front_end/testcases/general/bug32866.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract get f() → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends core::Object implements self::B {
+  final field core::String* f;
+  constructor •(core::String* f) → self::A*
+    : self::A::f = f, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::A* a = new self::A::•("foo");
+static method main() → dynamic
+  return core::print(self::a);
diff --git a/pkg/front_end/testcases/general/bug33099.dart.weak.modular.expect b/pkg/front_end/testcases/general/bug33099.dart.weak.modular.expect
new file mode 100644
index 0000000..68aa1c4
--- /dev/null
+++ b/pkg/front_end/testcases/general/bug33099.dart.weak.modular.expect
@@ -0,0 +1,93 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:mirrors" as mir;
+
+import "dart:mirrors";
+
+class _FailingTest extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::_FailingTest*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class MyTest extends core::Object {
+  synthetic constructor •() → self::MyTest*
+    : super core::Object::•()
+    ;
+  @#C1
+  method foo() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _MyTest2&Object&MyTest = core::Object with self::MyTest /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_MyTest2&Object&MyTest*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method foo() → void
+    return super.{self::MyTest::foo}();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class MyTest2 extends self::_MyTest2&Object&MyTest {
+  synthetic constructor •() → self::MyTest2*
+    : super self::_MyTest2&Object&MyTest::•()
+    ;
+}
+static const field self::_FailingTest* failingTest = #C1;
+static method main() → dynamic {
+  mir::ClassMirror* classMirror = mir::reflectClass(#C2);
+  classMirror.{mir::ClassMirror::instanceMembers}{core::Map<core::Symbol*, mir::MethodMirror*>*}.{core::Map::forEach}((core::Symbol* symbol, mir::MethodMirror* memberMirror) → Null {
+    if(memberMirror.{mir::DeclarationMirror::simpleName}{core::Symbol*} =={core::Symbol::==}{(core::Object*) →* core::bool*} #C3) {
+      core::print(memberMirror);
+      core::print(self::_hasFailingTestAnnotation(memberMirror));
+    }
+  }){((core::Symbol*, mir::MethodMirror*) →* void) →* void};
+}
+static method _hasFailingTestAnnotation(mir::MethodMirror* method) → core::bool* {
+  core::bool* r = self::_hasAnnotationInstance(method, #C1);
+  core::print("[_hasFailingTestAnnotation] ${method} ${r}");
+  return r;
+}
+static method _hasAnnotationInstance(mir::DeclarationMirror* declaration, dynamic instance) → core::bool*
+  return declaration.{mir::DeclarationMirror::metadata}{core::List<mir::InstanceMirror*>*}.{core::Iterable::any}((mir::InstanceMirror* annotation) → core::bool* {
+    core::print("annotation: ${annotation.{mir::InstanceMirror::reflectee}{dynamic}}");
+    return core::identical(annotation.{mir::InstanceMirror::reflectee}{dynamic}, instance);
+  }){((mir::InstanceMirror*) →* core::bool*) →* core::bool*};
+
+constants  {
+  #C1 = self::_FailingTest {}
+  #C2 = TypeLiteralConstant(self::MyTest2*)
+  #C3 = #foo
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///bug33099.dart:
+- _FailingTest. (from org-dartlang-testcase:///bug33099.dart:10:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/bug33196.dart.weak.modular.expect b/pkg/front_end/testcases/general/bug33196.dart.weak.modular.expect
new file mode 100644
index 0000000..306df2a
--- /dev/null
+++ b/pkg/front_end/testcases/general/bug33196.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+static method main() → dynamic {
+  FutureOr<core::String*>* result = self::returnsString();
+  core::print(result.{core::Object::runtimeType}{core::Type*});
+}
+static method returnsString() → FutureOr<core::String*>* async {
+  return "oh no";
+}
diff --git a/pkg/front_end/testcases/general/bug33206.dart.weak.modular.expect b/pkg/front_end/testcases/general/bug33206.dart.weak.modular.expect
new file mode 100644
index 0000000..b73a7ce
--- /dev/null
+++ b/pkg/front_end/testcases/general/bug33206.dart.weak.modular.expect
@@ -0,0 +1,58 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class X extends core::Object {
+  final field dynamic x;
+  final field dynamic y;
+  constructor •(dynamic x, dynamic y) → self::X*
+    : self::X::x = x, self::X::y = y, super core::Object::•()
+    ;
+  method toString() → core::String*
+    return "X(${this.{self::X::x}{dynamic}}, ${this.{self::X::y}{dynamic}})";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Y extends core::Object {
+  synthetic constructor •() → self::Y*
+    : super core::Object::•()
+    ;
+  method f(dynamic _) → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f1() → asy::Future<core::List<core::Object*>*>* async {
+  return <core::Object*>[1];
+}
+static method f2() → core::List<core::Object*>*
+  return <core::Object*>[2];
+static method f3() → asy::Future<core::Object*>* async {
+  return 3;
+}
+static method foo() → asy::Future<self::X*>* async {
+  return new self::X::•(let final self::Y* #t1 = new self::Y::•() in block {
+    #t1.{self::Y::f}(await self::f1()){(dynamic) →* dynamic};
+    #t1.{self::Y::f}(self::f2()){(dynamic) →* dynamic};
+  } =>#t1, await self::f3());
+}
+static method main() → asy::Future<void>* async {
+  core::print(await self::foo());
+}
diff --git a/pkg/front_end/testcases/general/bug33298.dart.weak.modular.expect b/pkg/front_end/testcases/general/bug33298.dart.weak.modular.expect
new file mode 100644
index 0000000..d656910
--- /dev/null
+++ b/pkg/front_end/testcases/general/bug33298.dart.weak.modular.expect
@@ -0,0 +1,76 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/bug33298.dart:28:44: Error: The argument type 'T Function<T>(T)' can't be assigned to the parameter type 'dynamic Function(String)'.
+//   List<String> list6 = ['a', 'b', 'c'].map(c).toList();
+//                                            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method call(core::String* s) → core::String*
+    return "${s}${s}";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  method call(covariant-by-class self::B::T* t) → self::B::T*
+    return t;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method call<T extends core::Object* = dynamic>(self::C::call::T* t) → self::C::call::T*
+    return t;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  self::A* a = new self::A::•();
+  core::List<core::String*>* list1 = <core::String*>["a", "b", "c"].{core::Iterable::map}<core::String*>(a.{self::A::call}{(core::String*) →* core::String*}){((core::String*) →* core::String*) →* core::Iterable<core::String*>*}.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<core::String*>*};
+  core::List<core::String*>* list2 = <core::String*>["a", "b", "c"].{core::Iterable::map}<core::String*>(let final self::A* #t1 = a in #t1 == null ?{(core::String*) →* core::String*} null : #t1.{self::A::call}{(core::String*) →* core::String*}){((core::String*) →* core::String*) →* core::Iterable<core::String*>*}.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<core::String*>*};
+  self::B<core::String*>* b = new self::B::•<core::String*>();
+  core::List<core::String*>* list3 = <core::String*>["a", "b", "c"].{core::Iterable::map}<core::String*>(b.{self::B::call}{(core::String*) →* core::String*}){((core::String*) →* core::String*) →* core::Iterable<core::String*>*}.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<core::String*>*};
+  core::List<core::String*>* list4 = <core::String*>["a", "b", "c"].{core::Iterable::map}<core::String*>(let final self::B<core::String*>* #t2 = b in #t2 == null ?{(core::String*) →* core::String*} null : #t2.{self::B::call}{(core::String*) →* core::String*}){((core::String*) →* core::String*) →* core::Iterable<core::String*>*}.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<core::String*>*};
+  self::C* c = new self::C::•();
+  core::List<core::String*>* list5 = <core::String*>["a", "b", "c"].{core::Iterable::map}<core::String*>(c.{self::C::call}{<T extends core::Object* = dynamic>(T*) →* T*}<core::String*>){((core::String*) →* core::String*) →* core::Iterable<core::String*>*}.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<core::String*>*};
+  core::List<core::String*>* list6 = <core::String*>["a", "b", "c"].{core::Iterable::map}<dynamic>(invalid-expression "pkg/front_end/testcases/general/bug33298.dart:28:44: Error: The argument type 'T Function<T>(T)' can't be assigned to the parameter type 'dynamic Function(String)'.
+  List<String> list6 = ['a', 'b', 'c'].map(c).toList();
+                                           ^" in (let final self::C* #t3 = c in #t3 == null ?{<T extends core::Object* = dynamic>(T*) →* T*} null : #t3.{self::C::call}{<T extends core::Object* = dynamic>(T*) →* T*}) as{TypeError} (core::String*) →* dynamic){((core::String*) →* dynamic) →* core::Iterable<dynamic>*}.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<dynamic>*} as{TypeError} core::List<core::String*>*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/bug34511.dart.weak.modular.expect b/pkg/front_end/testcases/general/bug34511.dart.weak.modular.expect
new file mode 100644
index 0000000..5cda82c
--- /dev/null
+++ b/pkg/front_end/testcases/general/bug34511.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _B&Object&A<Z extends core::Object* = dynamic> = core::Object with self::A<() →* self::_B&Object&A::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_B&Object&A<self::_B&Object&A::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<Z extends core::Object* = dynamic> extends self::_B&Object&A<self::B::Z*> {
+  synthetic constructor •() → self::B<self::B::Z*>*
+    : super self::_B&Object&A::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/bug35470.dart.weak.modular.expect b/pkg/front_end/testcases/general/bug35470.dart.weak.modular.expect
new file mode 100644
index 0000000..bc15f31
--- /dev/null
+++ b/pkg/front_end/testcases/general/bug35470.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  method foo<covariant-by-class Y extends self::A::X*>() → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A<dynamic> {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+static method bar(self::B* b) → dynamic {
+  b.{self::A::foo}<dynamic>(){() →* dynamic};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/bug37476.dart.weak.modular.expect b/pkg/front_end/testcases/general/bug37476.dart.weak.modular.expect
new file mode 100644
index 0000000..6cc98ca
--- /dev/null
+++ b/pkg/front_end/testcases/general/bug37476.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::num*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  method foo() → <S extends self::A::T* = dynamic>(S*) →* void {
+    core::print("foo: T = ${self::A::T*}");
+    return <S extends self::A::T*>(S* a) → Null {};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::num*> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  method foo() → (self::B::T*) →* void {
+    core::print("foo: T = ${self::B::T*}");
+    return (self::B::T* a) → Null {};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::A<core::num*>* a = new self::A::•<core::int*>();
+static field self::B<core::num*>* b = new self::B::•<core::int*>();
+static method main() → dynamic {
+  try {
+    self::a.{self::A::foo}(){() →* <S extends core::num* = dynamic>(S*) →* void} as{TypeError,CovarianceCheck} <S extends core::num* = dynamic>(S*) →* void;
+    throw "Expected TypeError";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    self::b.{self::B::foo}(){() →* (core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void;
+    throw "Expected TypeError";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+}
diff --git a/pkg/front_end/testcases/general/build_issue_2688.dart.weak.modular.expect b/pkg/front_end/testcases/general/build_issue_2688.dart.weak.modular.expect
new file mode 100644
index 0000000..226f3df
--- /dev/null
+++ b/pkg/front_end/testcases/general/build_issue_2688.dart.weak.modular.expect
@@ -0,0 +1,560 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class M0 extends core::Object /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M1 extends core::Object implements self::M0 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M2 extends core::Object implements self::M1 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M3 extends core::Object implements self::M2 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M4 extends core::Object implements self::M3 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M5 extends core::Object implements self::M4 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M6 extends core::Object implements self::M5 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M7 extends core::Object implements self::M6 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M8 extends core::Object implements self::M7 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M9 extends core::Object implements self::M8 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M10 extends core::Object implements self::M9 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M11 extends core::Object implements self::M10 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M12 extends core::Object implements self::M11 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M13 extends core::Object implements self::M12 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M14 extends core::Object implements self::M13 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M15 extends core::Object implements self::M14 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M16 extends core::Object implements self::M15 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M17 extends core::Object implements self::M16 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M18 extends core::Object implements self::M17 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M19 extends core::Object implements self::M18 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M20 extends core::Object implements self::M19 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M21 extends core::Object implements self::M20 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M22 extends core::Object implements self::M21 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M23 extends core::Object implements self::M22 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M24 extends core::Object implements self::M23 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M25 extends core::Object implements self::M24 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M26 extends core::Object implements self::M25 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M27 extends core::Object implements self::M26 /*isMixinDeclaration*/  {
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Super extends core::Object {
+  synthetic constructor •() → self::Super*
+    : super core::Object::•()
+    ;
+  abstract get property() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Class&Super&M0 = self::Super with self::M0 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0*
+    : super self::Super::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M0::property
+}
+abstract class _Class&Super&M0&M1 = self::_Class&Super&M0 with self::M1 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1*
+    : super self::_Class&Super&M0::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M1::property
+}
+abstract class _Class&Super&M0&M1&M2 = self::_Class&Super&M0&M1 with self::M2 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2*
+    : super self::_Class&Super&M0&M1::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M2::property
+}
+abstract class _Class&Super&M0&M1&M2&M3 = self::_Class&Super&M0&M1&M2 with self::M3 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3*
+    : super self::_Class&Super&M0&M1&M2::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M3::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4 = self::_Class&Super&M0&M1&M2&M3 with self::M4 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4*
+    : super self::_Class&Super&M0&M1&M2&M3::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M4::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5 = self::_Class&Super&M0&M1&M2&M3&M4 with self::M5 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5*
+    : super self::_Class&Super&M0&M1&M2&M3&M4::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M5::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6 = self::_Class&Super&M0&M1&M2&M3&M4&M5 with self::M6 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M6::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6 with self::M7 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M7::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7 with self::M8 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M8::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8 with self::M9 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M9::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9 with self::M10 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M10::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10 with self::M11 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M11::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11 with self::M12 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M12::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12 with self::M13 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M13::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13 with self::M14 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M14::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14 with self::M15 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M15::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15 with self::M16 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M16::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16 with self::M17 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M17::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17 with self::M18 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M18::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18 with self::M19 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M19::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19 with self::M20 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M20::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20 with self::M21 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M21::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21 with self::M22 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M22::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22 with self::M23 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M23::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23 with self::M24 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M24::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24 with self::M25 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M25::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25 with self::M26 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M26::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26&M27 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26 with self::M27 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26&M27*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26::•()
+    ;
+  abstract mixin-stub get property() → core::int*; -> self::M27::property
+}
+class Class extends self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26&M27 {
+  synthetic constructor •() → self::Class*
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26&M27::•()
+    ;
+  get property() → core::int*
+    return 0;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/call.dart.weak.modular.expect b/pkg/front_end/testcases/general/call.dart.weak.modular.expect
new file mode 100644
index 0000000..f9559169
--- /dev/null
+++ b/pkg/front_end/testcases/general/call.dart.weak.modular.expect
@@ -0,0 +1,234 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/call.dart:29:31: Error: Cannot invoke an instance of 'CallableGetter' because it declares 'call' to be something other than a method.
+//  - 'CallableGetter' is from 'pkg/front_end/testcases/general/call.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+//   var string5 = callableGetter(1);
+//                               ^
+//
+// pkg/front_end/testcases/general/call.dart:34:25: Error: Too few positional arguments: 1 required, 0 given.
+//   var nothing1 = closure();
+//                         ^
+//
+// pkg/front_end/testcases/general/call.dart:35:30: Error: Too few positional arguments: 1 required, 0 given.
+//   var nothing2 = closure.call();
+//                              ^
+//
+// pkg/front_end/testcases/general/call.dart:36:35: Error: Too few positional arguments: 1 required, 0 given.
+//   var nothing3 = closure.call.call();
+//                                   ^
+//
+// pkg/front_end/testcases/general/call.dart:37:40: Error: Too few positional arguments: 1 required, 0 given.
+//   var nothing4 = closure.call.call.call();
+//                                        ^
+//
+// pkg/front_end/testcases/general/call.dart:39:26: Error: Too few positional arguments: 1 required, 0 given.
+//   var nothing5 = callable();
+//                          ^
+//
+// pkg/front_end/testcases/general/call.dart:40:31: Error: Too few positional arguments: 1 required, 0 given.
+//   var nothing6 = callable.call();
+//                               ^
+//
+// pkg/front_end/testcases/general/call.dart:41:36: Error: Too few positional arguments: 1 required, 0 given.
+//   var nothing7 = callable.call.call();
+//                                    ^
+//
+// pkg/front_end/testcases/general/call.dart:42:41: Error: Too few positional arguments: 1 required, 0 given.
+//   var nothing8 = callable.call.call.call();
+//                                         ^
+//
+// pkg/front_end/testcases/general/call.dart:44:32: Error: Cannot invoke an instance of 'CallableGetter' because it declares 'call' to be something other than a method.
+//  - 'CallableGetter' is from 'pkg/front_end/testcases/general/call.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+//   var nothing9 = callableGetter();
+//                                ^
+//
+// pkg/front_end/testcases/general/call.dart:63:29: Error: Cannot invoke an instance of 'CallableGetter' because it declares 'call' to be something other than a method.
+//  - 'CallableGetter' is from 'pkg/front_end/testcases/general/call.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+// var string5 = callableGetter(1);
+//                             ^
+//
+// pkg/front_end/testcases/general/call.dart:68:23: Error: Too few positional arguments: 1 required, 0 given.
+// var nothing1 = closure();
+//                       ^
+//
+// pkg/front_end/testcases/general/call.dart:69:28: Error: Too few positional arguments: 1 required, 0 given.
+// var nothing2 = closure.call();
+//                            ^
+//
+// pkg/front_end/testcases/general/call.dart:70:33: Error: Too few positional arguments: 1 required, 0 given.
+// var nothing3 = closure.call.call();
+//                                 ^
+//
+// pkg/front_end/testcases/general/call.dart:71:38: Error: Too few positional arguments: 1 required, 0 given.
+// var nothing4 = closure.call.call.call();
+//                                      ^
+//
+// pkg/front_end/testcases/general/call.dart:73:24: Error: Too few positional arguments: 1 required, 0 given.
+// var nothing5 = callable();
+//                        ^
+//
+// pkg/front_end/testcases/general/call.dart:74:29: Error: Too few positional arguments: 1 required, 0 given.
+// var nothing6 = callable.call();
+//                             ^
+//
+// pkg/front_end/testcases/general/call.dart:75:34: Error: Too few positional arguments: 1 required, 0 given.
+// var nothing7 = callable.call.call();
+//                                  ^
+//
+// pkg/front_end/testcases/general/call.dart:76:39: Error: Too few positional arguments: 1 required, 0 given.
+// var nothing8 = callable.call.call.call();
+//                                       ^
+//
+// pkg/front_end/testcases/general/call.dart:78:30: Error: Cannot invoke an instance of 'CallableGetter' because it declares 'call' to be something other than a method.
+//  - 'CallableGetter' is from 'pkg/front_end/testcases/general/call.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+// var nothing9 = callableGetter();
+//                              ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Callable extends core::Object {
+  synthetic constructor •() → self::Callable*
+    : super core::Object::•()
+    ;
+  method call(dynamic x) → dynamic {
+    return "string";
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class CallableGetter extends core::Object {
+  synthetic constructor •() → self::CallableGetter*
+    : super core::Object::•()
+    ;
+  get call() → dynamic
+    return new self::Callable::•();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field (dynamic) →* dynamic closure = (dynamic x) → dynamic => x;
+static field dynamic int1 = self::closure(1){(dynamic) →* dynamic};
+static field dynamic int2 = self::closure(1){(dynamic) →* dynamic};
+static field dynamic int3 = self::closure.call(1){(dynamic) →* dynamic};
+static field dynamic int4 = self::closure.call.call(1){(dynamic) →* dynamic};
+static field self::Callable* callable = new self::Callable::•();
+static field dynamic string1 = self::callable.{self::Callable::call}(1){(dynamic) →* dynamic};
+static field dynamic string2 = self::callable.{self::Callable::call}(1){(dynamic) →* dynamic};
+static field dynamic string3 = self::callable.{self::Callable::call}{(dynamic) →* dynamic}(1){(dynamic) →* dynamic};
+static field dynamic string4 = self::callable.{self::Callable::call}{(dynamic) →* dynamic}.call(1){(dynamic) →* dynamic};
+static field self::CallableGetter* callableGetter = new self::CallableGetter::•();
+static field invalid-type string5 = invalid-expression "pkg/front_end/testcases/general/call.dart:63:29: Error: Cannot invoke an instance of 'CallableGetter' because it declares 'call' to be something other than a method.
+ - 'CallableGetter' is from 'pkg/front_end/testcases/general/call.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+var string5 = callableGetter(1);
+                            ^";
+static field dynamic string6 = let final self::CallableGetter* #t1 = self::callableGetter in let final core::int* #t2 = 1 in #t1.{self::CallableGetter::call}{dynamic}{dynamic}.call(#t2);
+static field dynamic string7 = self::callableGetter.{self::CallableGetter::call}{dynamic}{dynamic}.call(1);
+static field dynamic string8 = self::callableGetter.{self::CallableGetter::call}{dynamic}{dynamic}.call{dynamic}.call(1);
+static field dynamic nothing1 = invalid-expression "pkg/front_end/testcases/general/call.dart:68:23: Error: Too few positional arguments: 1 required, 0 given.
+var nothing1 = closure();
+                      ^" in self::closure{<inapplicable>}.();
+static field dynamic nothing2 = invalid-expression "pkg/front_end/testcases/general/call.dart:69:28: Error: Too few positional arguments: 1 required, 0 given.
+var nothing2 = closure.call();
+                           ^" in self::closure{<inapplicable>}.();
+static field dynamic nothing3 = invalid-expression "pkg/front_end/testcases/general/call.dart:70:33: Error: Too few positional arguments: 1 required, 0 given.
+var nothing3 = closure.call.call();
+                                ^" in self::closure.call{<inapplicable>}.();
+static field dynamic nothing4 = invalid-expression "pkg/front_end/testcases/general/call.dart:71:38: Error: Too few positional arguments: 1 required, 0 given.
+var nothing4 = closure.call.call.call();
+                                     ^" in self::closure.call.call{<inapplicable>}.();
+static field dynamic nothing5 = invalid-expression "pkg/front_end/testcases/general/call.dart:73:24: Error: Too few positional arguments: 1 required, 0 given.
+var nothing5 = callable();
+                       ^" in self::callable.{self::Callable::call}{<inapplicable>}.(){() →* invalid-type};
+static field dynamic nothing6 = invalid-expression "pkg/front_end/testcases/general/call.dart:74:29: Error: Too few positional arguments: 1 required, 0 given.
+var nothing6 = callable.call();
+                            ^" in self::callable.{self::Callable::call}{<inapplicable>}.(){() →* invalid-type};
+static field dynamic nothing7 = invalid-expression "pkg/front_end/testcases/general/call.dart:75:34: Error: Too few positional arguments: 1 required, 0 given.
+var nothing7 = callable.call.call();
+                                 ^" in self::callable.{self::Callable::call}{(dynamic) →* dynamic}{<inapplicable>}.();
+static field dynamic nothing8 = invalid-expression "pkg/front_end/testcases/general/call.dart:76:39: Error: Too few positional arguments: 1 required, 0 given.
+var nothing8 = callable.call.call.call();
+                                      ^" in self::callable.{self::Callable::call}{(dynamic) →* dynamic}.call{<inapplicable>}.();
+static field invalid-type nothing9 = invalid-expression "pkg/front_end/testcases/general/call.dart:78:30: Error: Cannot invoke an instance of 'CallableGetter' because it declares 'call' to be something other than a method.
+ - 'CallableGetter' is from 'pkg/front_end/testcases/general/call.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+var nothing9 = callableGetter();
+                             ^";
+static field dynamic nothing10 = self::callableGetter.{self::CallableGetter::call}{dynamic}{dynamic}.call();
+static field dynamic nothing11 = self::callableGetter.{self::CallableGetter::call}{dynamic}{dynamic}.call();
+static field dynamic nothing12 = self::callableGetter.{self::CallableGetter::call}{dynamic}{dynamic}.call{dynamic}.call();
+static method main() → dynamic {
+  (dynamic) →* dynamic closure = (dynamic x) → dynamic => x;
+  dynamic int1 = closure(1){(dynamic) →* dynamic};
+  dynamic int2 = closure(1){(dynamic) →* dynamic};
+  dynamic int3 = closure.call(1){(dynamic) →* dynamic};
+  dynamic int4 = closure.call.call(1){(dynamic) →* dynamic};
+  self::Callable* callable = new self::Callable::•();
+  dynamic string1 = callable.{self::Callable::call}(1){(dynamic) →* dynamic};
+  dynamic string2 = callable.{self::Callable::call}(1){(dynamic) →* dynamic};
+  dynamic string3 = callable.{self::Callable::call}{(dynamic) →* dynamic}(1){(dynamic) →* dynamic};
+  dynamic string4 = callable.{self::Callable::call}{(dynamic) →* dynamic}.call(1){(dynamic) →* dynamic};
+  self::CallableGetter* callableGetter = new self::CallableGetter::•();
+  invalid-type string5 = invalid-expression "pkg/front_end/testcases/general/call.dart:29:31: Error: Cannot invoke an instance of 'CallableGetter' because it declares 'call' to be something other than a method.
+ - 'CallableGetter' is from 'pkg/front_end/testcases/general/call.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+  var string5 = callableGetter(1);
+                              ^";
+  dynamic string6 = let final self::CallableGetter* #t3 = callableGetter in let final core::int* #t4 = 1 in #t3.{self::CallableGetter::call}{dynamic}{dynamic}.call(#t4);
+  dynamic string7 = callableGetter.{self::CallableGetter::call}{dynamic}{dynamic}.call(1);
+  dynamic string8 = callableGetter.{self::CallableGetter::call}{dynamic}{dynamic}.call{dynamic}.call(1);
+  invalid-type nothing1 = invalid-expression "pkg/front_end/testcases/general/call.dart:34:25: Error: Too few positional arguments: 1 required, 0 given.
+  var nothing1 = closure();
+                        ^" in closure{<inapplicable>}.();
+  invalid-type nothing2 = invalid-expression "pkg/front_end/testcases/general/call.dart:35:30: Error: Too few positional arguments: 1 required, 0 given.
+  var nothing2 = closure.call();
+                             ^" in closure{<inapplicable>}.();
+  invalid-type nothing3 = invalid-expression "pkg/front_end/testcases/general/call.dart:36:35: Error: Too few positional arguments: 1 required, 0 given.
+  var nothing3 = closure.call.call();
+                                  ^" in closure.call{<inapplicable>}.();
+  invalid-type nothing4 = invalid-expression "pkg/front_end/testcases/general/call.dart:37:40: Error: Too few positional arguments: 1 required, 0 given.
+  var nothing4 = closure.call.call.call();
+                                       ^" in closure.call.call{<inapplicable>}.();
+  invalid-type nothing5 = invalid-expression "pkg/front_end/testcases/general/call.dart:39:26: Error: Too few positional arguments: 1 required, 0 given.
+  var nothing5 = callable();
+                         ^" in callable.{self::Callable::call}{<inapplicable>}.(){() →* invalid-type};
+  invalid-type nothing6 = invalid-expression "pkg/front_end/testcases/general/call.dart:40:31: Error: Too few positional arguments: 1 required, 0 given.
+  var nothing6 = callable.call();
+                              ^" in callable.{self::Callable::call}{<inapplicable>}.(){() →* invalid-type};
+  invalid-type nothing7 = invalid-expression "pkg/front_end/testcases/general/call.dart:41:36: Error: Too few positional arguments: 1 required, 0 given.
+  var nothing7 = callable.call.call();
+                                   ^" in callable.{self::Callable::call}{(dynamic) →* dynamic}{<inapplicable>}.();
+  invalid-type nothing8 = invalid-expression "pkg/front_end/testcases/general/call.dart:42:41: Error: Too few positional arguments: 1 required, 0 given.
+  var nothing8 = callable.call.call.call();
+                                        ^" in callable.{self::Callable::call}{(dynamic) →* dynamic}.call{<inapplicable>}.();
+  invalid-type nothing9 = invalid-expression "pkg/front_end/testcases/general/call.dart:44:32: Error: Cannot invoke an instance of 'CallableGetter' because it declares 'call' to be something other than a method.
+ - 'CallableGetter' is from 'pkg/front_end/testcases/general/call.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+  var nothing9 = callableGetter();
+                               ^";
+  dynamic nothing10 = callableGetter.{self::CallableGetter::call}{dynamic}{dynamic}.call();
+  dynamic nothing11 = callableGetter.{self::CallableGetter::call}{dynamic}{dynamic}.call();
+  dynamic nothing12 = callableGetter.{self::CallableGetter::call}{dynamic}{dynamic}.call{dynamic}.call();
+}
diff --git a/pkg/front_end/testcases/general/callable_type_variable.dart.weak.modular.expect b/pkg/front_end/testcases/general/callable_type_variable.dart.weak.modular.expect
new file mode 100644
index 0000000..82b2ca3
--- /dev/null
+++ b/pkg/front_end/testcases/general/callable_type_variable.dart.weak.modular.expect
@@ -0,0 +1,66 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/callable_type_variable.dart:25:19: Error: Too few positional arguments: 1 required, 0 given.
+//     var v1 = field(); // error
+//                   ^
+//
+// pkg/front_end/testcases/general/callable_type_variable.dart:28:24: Error: Too few positional arguments: 1 required, 0 given.
+//     var v4 = field.call(); // error
+//                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1<T extends core::Function*> extends core::Object {
+  covariant-by-class field self::Class1::T* field;
+  constructor •(self::Class1::T* field) → self::Class1<self::Class1::T*>*
+    : self::Class1::field = field, super core::Object::•()
+    ;
+  method method() → dynamic {
+    dynamic v1 = this.{self::Class1::field}{self::Class1::T*}();
+    dynamic v2 = let final core::int* #t1 = 0 in this.{self::Class1::field}{self::Class1::T*}(#t1);
+    self::Class1::T* v3 = this.{self::Class1::field}{self::Class1::T*}.call;
+    dynamic v4 = this.{self::Class1::field}{self::Class1::T*}();
+    dynamic v5 = this.{self::Class1::field}{self::Class1::T*}(0);
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class2<T extends (core::int*) →* core::String*> extends core::Object {
+  covariant-by-class field self::Class2::T* field;
+  constructor •(self::Class2::T* field) → self::Class2<self::Class2::T*>*
+    : self::Class2::field = field, super core::Object::•()
+    ;
+  method method() → dynamic {
+    invalid-type v1 = invalid-expression "pkg/front_end/testcases/general/callable_type_variable.dart:25:19: Error: Too few positional arguments: 1 required, 0 given.
+    var v1 = field(); // error
+                  ^" in this.{self::Class2::field}{self::Class2::T*}{<inapplicable>}.();
+    core::String* v2 = let final core::int* #t2 = 0 in this.{self::Class2::field}{self::Class2::T*}(#t2){(core::int*) →* core::String*};
+    self::Class2::T* v3 = this.{self::Class2::field}{self::Class2::T*}.call;
+    invalid-type v4 = invalid-expression "pkg/front_end/testcases/general/callable_type_variable.dart:28:24: Error: Too few positional arguments: 1 required, 0 given.
+    var v4 = field.call(); // error
+                       ^" in this.{self::Class2::field}{self::Class2::T*}{<inapplicable>}.();
+    core::String* v5 = this.{self::Class2::field}{self::Class2::T*}(0){(core::int*) →* core::String*};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/candidate_found.dart.weak.modular.expect b/pkg/front_end/testcases/general/candidate_found.dart.weak.modular.expect
new file mode 100644
index 0000000..a8817a7
--- /dev/null
+++ b/pkg/front_end/testcases/general/candidate_found.dart.weak.modular.expect
@@ -0,0 +1,85 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/candidate_found.dart:16:11: Error: Too few positional arguments: 1 required, 0 given.
+//   new Fisk();
+//           ^
+// pkg/front_end/testcases/general/candidate_found.dart:6:3: Context: Found this candidate, but the arguments don't match.
+//   Fisk(int x) {}
+//   ^^^^
+//
+// pkg/front_end/testcases/general/candidate_found.dart:17:17: Error: Too few positional arguments: 1 required, 0 given.
+//   new Fisk.named();
+//                 ^
+// pkg/front_end/testcases/general/candidate_found.dart:8:3: Context: Found this candidate, but the arguments don't match.
+//   Fisk.named(int x) {}
+//   ^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/candidate_found.dart:18:7: Error: Too few positional arguments: 1 required, 0 given.
+//   Fisk();
+//       ^
+// pkg/front_end/testcases/general/candidate_found.dart:6:3: Context: Found this candidate, but the arguments don't match.
+//   Fisk(int x) {}
+//   ^^^^
+//
+// pkg/front_end/testcases/general/candidate_found.dart:19:13: Error: Too few positional arguments: 1 required, 0 given.
+//   Fisk.named();
+//             ^
+// pkg/front_end/testcases/general/candidate_found.dart:8:3: Context: Found this candidate, but the arguments don't match.
+//   Fisk.named(int x) {}
+//   ^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/candidate_found.dart:20:20: Error: Too few positional arguments: 1 required, 0 given.
+//   Fisk.staticMethod();
+//                    ^
+// pkg/front_end/testcases/general/candidate_found.dart:12:15: Context: Found this candidate, but the arguments don't match.
+//   static void staticMethod(int x) {}
+//               ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/candidate_found.dart:21:24: Error: Too few positional arguments: 1 required, 0 given.
+//   (null as Fisk).method();
+//                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Fisk extends core::Object {
+  constructor •(core::int* x) → self::Fisk*
+    : super core::Object::•() {}
+  constructor named(core::int* x) → self::Fisk*
+    : super core::Object::•() {}
+  method method(core::int* x) → void {}
+  static method staticMethod(core::int* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/candidate_found.dart:16:11: Error: Too few positional arguments: 1 required, 0 given.
+  new Fisk();
+          ^";
+  invalid-expression "pkg/front_end/testcases/general/candidate_found.dart:17:17: Error: Too few positional arguments: 1 required, 0 given.
+  new Fisk.named();
+                ^";
+  invalid-expression "pkg/front_end/testcases/general/candidate_found.dart:18:7: Error: Too few positional arguments: 1 required, 0 given.
+  Fisk();
+      ^";
+  invalid-expression "pkg/front_end/testcases/general/candidate_found.dart:19:13: Error: Too few positional arguments: 1 required, 0 given.
+  Fisk.named();
+            ^";
+  invalid-expression "pkg/front_end/testcases/general/candidate_found.dart:20:20: Error: Too few positional arguments: 1 required, 0 given.
+  Fisk.staticMethod();
+                   ^";
+  invalid-expression "pkg/front_end/testcases/general/candidate_found.dart:21:24: Error: Too few positional arguments: 1 required, 0 given.
+  (null as Fisk).method();
+                       ^" in (null as self::Fisk*).{self::Fisk::method}{<inapplicable>}.(){() →* invalid-type};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/cascade.dart.weak.modular.expect b/pkg/front_end/testcases/general/cascade.dart.weak.modular.expect
new file mode 100644
index 0000000..3d4d8ca
--- /dev/null
+++ b/pkg/front_end/testcases/general/cascade.dart.weak.modular.expect
@@ -0,0 +1,65 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/cascade.dart:26:5: Error: A value of type 'List<int>' can't be assigned to a variable of type 'int'.
+//  - 'List' is from 'dart:core'.
+//     [1]
+//     ^
+//
+// pkg/front_end/testcases/general/cascade.dart:28:13: Error: The getter 'last' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'last'.
+//     ..first.last.toString()
+//             ^^^^
+//
+// pkg/front_end/testcases/general/cascade.dart:29:12: Error: The operator '[]' isn't defined for the class 'int'.
+// Try correcting the operator to an existing operator, or defining a '[]' operator.
+//     ..first[0].toString()
+//            ^
+//
+// pkg/front_end/testcases/general/cascade.dart:30:11: Error: The getter 'last' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'last'.
+//     ..[0].last.toString();
+//           ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::List<core::int*>* list = let final core::List<core::int*>* #t1 = <core::int*>[1] in block {
+    #t1.{core::List::add}(2){(core::int*) →* void};
+    #t1.{core::List::add}(3){(core::int*) →* void};
+    #t1.{core::List::addAll}(<core::int*>[4, 5]){(core::Iterable<core::int*>*) →* void};
+  } =>#t1;
+  core::print(list);
+  let final core::List<core::int*>* #t2 = list in block {
+    #t2.{core::List::add}(2){(core::int*) →* void};
+    #t2.{core::List::length}{core::int*};
+    #t2.{core::List::length} = 0;
+  } =>#t2;
+  core::print(list);
+  let final core::List<core::int*>* #t3 = list in block {
+    #t3.{core::List::add}(2){(core::int*) →* void};
+    #t3.{core::List::[]}(0){(core::int*) →* core::int*};
+    #t3.{core::List::[]=}(0, 87){(core::int*, core::int*) →* void};
+  } =>#t3;
+  core::print(list);
+  list = let final core::List<core::int*>* #t4 = <core::int*>[invalid-expression "pkg/front_end/testcases/general/cascade.dart:26:5: Error: A value of type 'List<int>' can't be assigned to a variable of type 'int'.
+ - 'List' is from 'dart:core'.
+    [1]
+    ^" in <core::int*>[1] as{TypeError} core::int*] in block {
+    invalid-expression "pkg/front_end/testcases/general/cascade.dart:28:13: Error: The getter 'last' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'last'.
+    ..first.last.toString()
+            ^^^^" in #t4.{core::Iterable::first}{core::int*}{<unresolved>}.last.{core::Object::toString}(){() →* core::String*};
+    invalid-expression "pkg/front_end/testcases/general/cascade.dart:29:12: Error: The operator '[]' isn't defined for the class 'int'.
+Try correcting the operator to an existing operator, or defining a '[]' operator.
+    ..first[0].toString()
+           ^" in #t4.{core::Iterable::first}{core::int*}{<unresolved>}.[](0).{core::Object::toString}(){() →* core::String*};
+    invalid-expression "pkg/front_end/testcases/general/cascade.dart:30:11: Error: The getter 'last' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'last'.
+    ..[0].last.toString();
+          ^^^^" in #t4.{core::List::[]}(0){(core::int*) →* core::int*}{<unresolved>}.last.{core::Object::toString}(){() →* core::String*};
+  } =>#t4;
+  core::print(list);
+}
diff --git a/pkg/front_end/testcases/general/cascade_context.dart.weak.modular.expect b/pkg/front_end/testcases/general/cascade_context.dart.weak.modular.expect
new file mode 100644
index 0000000..11f2c0b
--- /dev/null
+++ b/pkg/front_end/testcases/general/cascade_context.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method test() → dynamic {
+  core::int* v1 = self::f<core::int*>();
+  core::int* v2 = let final core::int* #t1 = self::f<core::int*>() in block {
+    #t1.{core::int::isEven}{core::bool*};
+  } =>#t1;
+  core::int* v3 = let final core::int* #t2 = self::f<core::int*>() in block {
+    #t2.{core::int::isEven}{core::bool*};
+    #t2.{core::int::isEven}{core::bool*};
+  } =>#t2;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/casts.dart.weak.modular.expect b/pkg/front_end/testcases/general/casts.dart.weak.modular.expect
new file mode 100644
index 0000000..bfac5fe
--- /dev/null
+++ b/pkg/front_end/testcases/general/casts.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::print("" as core::String*);
+  core::print(1 as core::int*);
+  core::print(1.0 as core::double*);
+  core::print("" is core::String*);
+  core::print("" is core::int*);
+  core::print("" is core::double*);
+  core::print(1 is core::String*);
+  core::print(1 is core::int*);
+  core::print(1 is core::double*);
+  core::print(1.0 is core::String*);
+  core::print(1.0 is core::int*);
+  core::print(1.0 is core::double*);
+}
diff --git a/pkg/front_end/testcases/general/check_deferred_allocation.dart.weak.modular.expect b/pkg/front_end/testcases/general/check_deferred_allocation.dart.weak.modular.expect
new file mode 100644
index 0000000..ee44558
--- /dev/null
+++ b/pkg/front_end/testcases/general/check_deferred_allocation.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "deferred_lib.dart" as def;
+
+import "org-dartlang-testcase:///deferred_lib.dart" deferred as lib;
+
+static method main() → dynamic {}
+static method test() → dynamic {
+  core::print(let final dynamic #t1 = CheckLibraryIsLoaded(lib) in new def::C::•());
+}
+
+library;
+import self as def;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::int* y = 1;
+  synthetic constructor •() → def::C*
+    : super core::Object::•()
+    ;
+  static method m() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* x = 0;
+static method m(dynamic x) → dynamic
+  return null;
diff --git a/pkg/front_end/testcases/general/check_deferred_as_check.dart.weak.modular.expect b/pkg/front_end/testcases/general/check_deferred_as_check.dart.weak.modular.expect
new file mode 100644
index 0000000..3ed13e8
--- /dev/null
+++ b/pkg/front_end/testcases/general/check_deferred_as_check.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/check_deferred_as_check.dart:9:8: Error: The type 'C' is deferred loaded via prefix 'lib' and can't be used as a type annotation.
+//  - 'C' is from 'pkg/front_end/testcases/general/deferred_lib.dart'.
+// Try removing 'deferred' from the import of 'lib' or use a supertype of 'C' that isn't deferred.
+//   x as lib.C;
+//        ^^^^^
+//
+import self as self;
+
+import "org-dartlang-testcase:///deferred_lib.dart" deferred as lib;
+
+static method main() → dynamic {}
+static method test(dynamic x) → dynamic {
+  x as invalid-type;
+}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::int* y = 1;
+  synthetic constructor •() → self2::C*
+    : super core::Object::•()
+    ;
+  static method m() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* x = 0;
+static method m(dynamic x) → dynamic
+  return null;
diff --git a/pkg/front_end/testcases/general/check_deferred_before_args.dart.weak.modular.expect b/pkg/front_end/testcases/general/check_deferred_before_args.dart.weak.modular.expect
new file mode 100644
index 0000000..a15d266
--- /dev/null
+++ b/pkg/front_end/testcases/general/check_deferred_before_args.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library;
+import self as self;
+import "deferred_lib.dart" as def;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///deferred_lib.dart" deferred as lib;
+
+static method main() → dynamic {}
+static method test() → dynamic {
+  let final dynamic #t1 = CheckLibraryIsLoaded(lib) in def::x = self::m2() as{TypeError,ForDynamic} core::int*;
+  let final dynamic #t2 = CheckLibraryIsLoaded(lib) in def::m(self::m2());
+}
+static method m2() → dynamic
+  return 1;
+
+library;
+import self as def;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::int* y = 1;
+  synthetic constructor •() → def::C*
+    : super core::Object::•()
+    ;
+  static method m() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* x = 0;
+static method m(dynamic x) → dynamic
+  return null;
diff --git a/pkg/front_end/testcases/general/check_deferred_before_args2.dart.weak.modular.expect b/pkg/front_end/testcases/general/check_deferred_before_args2.dart.weak.modular.expect
new file mode 100644
index 0000000..12e71e3
--- /dev/null
+++ b/pkg/front_end/testcases/general/check_deferred_before_args2.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library;
+import self as self;
+import "deferred_lib.dart" as def;
+
+import "org-dartlang-testcase:///deferred_lib.dart" deferred as lib;
+
+static method main() → dynamic {}
+static method test() → dynamic async {
+  let final dynamic #t1 = CheckLibraryIsLoaded(lib) in def::m(await LoadLibrary(lib));
+}
+
+library;
+import self as def;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::int* y = 1;
+  synthetic constructor •() → def::C*
+    : super core::Object::•()
+    ;
+  static method m() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* x = 0;
+static method m(dynamic x) → dynamic
+  return null;
diff --git a/pkg/front_end/testcases/general/check_deferred_before_call.dart.weak.modular.expect b/pkg/front_end/testcases/general/check_deferred_before_call.dart.weak.modular.expect
new file mode 100644
index 0000000..1d2d900
--- /dev/null
+++ b/pkg/front_end/testcases/general/check_deferred_before_call.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library;
+import self as self;
+import "deferred_lib.dart" as def;
+
+import "org-dartlang-testcase:///deferred_lib.dart" deferred as lib;
+
+static method main() → dynamic {}
+static method test() → dynamic {
+  let final dynamic #t1 = CheckLibraryIsLoaded(lib) in def::m(3);
+}
+
+library;
+import self as def;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::int* y = 1;
+  synthetic constructor •() → def::C*
+    : super core::Object::•()
+    ;
+  static method m() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* x = 0;
+static method m(dynamic x) → dynamic
+  return null;
diff --git a/pkg/front_end/testcases/general/check_deferred_before_write.dart.weak.modular.expect b/pkg/front_end/testcases/general/check_deferred_before_write.dart.weak.modular.expect
new file mode 100644
index 0000000..549e5e0
--- /dev/null
+++ b/pkg/front_end/testcases/general/check_deferred_before_write.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library;
+import self as self;
+import "deferred_lib.dart" as def;
+
+import "org-dartlang-testcase:///deferred_lib.dart" deferred as lib;
+
+static method main() → dynamic {}
+static method test() → dynamic {
+  let final dynamic #t1 = CheckLibraryIsLoaded(lib) in def::x = 2;
+}
+
+library;
+import self as def;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::int* y = 1;
+  synthetic constructor •() → def::C*
+    : super core::Object::•()
+    ;
+  static method m() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* x = 0;
+static method m(dynamic x) → dynamic
+  return null;
diff --git a/pkg/front_end/testcases/general/check_deferred_is_check.dart.weak.modular.expect b/pkg/front_end/testcases/general/check_deferred_is_check.dart.weak.modular.expect
new file mode 100644
index 0000000..08b44c2
--- /dev/null
+++ b/pkg/front_end/testcases/general/check_deferred_is_check.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/check_deferred_is_check.dart:9:14: Error: The type 'C' is deferred loaded via prefix 'lib' and can't be used as a type annotation.
+//  - 'C' is from 'pkg/front_end/testcases/general/deferred_lib.dart'.
+// Try removing 'deferred' from the import of 'lib' or use a supertype of 'C' that isn't deferred.
+//   print(x is lib.C);
+//              ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///deferred_lib.dart" deferred as lib;
+
+static method main() → dynamic {}
+static method test(dynamic x) → dynamic {
+  core::print(x is invalid-type);
+}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::int* y = 1;
+  synthetic constructor •() → self2::C*
+    : super core::Object::•()
+    ;
+  static method m() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* x = 0;
+static method m(dynamic x) → dynamic
+  return null;
diff --git a/pkg/front_end/testcases/general/check_deferred_read.dart.weak.modular.expect b/pkg/front_end/testcases/general/check_deferred_read.dart.weak.modular.expect
new file mode 100644
index 0000000..d298cb9
--- /dev/null
+++ b/pkg/front_end/testcases/general/check_deferred_read.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "deferred_lib.dart" as def;
+
+import "org-dartlang-testcase:///deferred_lib.dart" deferred as lib;
+
+static method main() → dynamic {}
+static method test() → dynamic {
+  core::print((let final dynamic #t1 = CheckLibraryIsLoaded(lib) in def::x).{core::num::+}(1){(core::num*) →* core::int*});
+}
+
+library;
+import self as def;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::int* y = 1;
+  synthetic constructor •() → def::C*
+    : super core::Object::•()
+    ;
+  static method m() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* x = 0;
+static method m(dynamic x) → dynamic
+  return null;
diff --git a/pkg/front_end/testcases/general/check_deferred_read_static_field.dart.weak.modular.expect b/pkg/front_end/testcases/general/check_deferred_read_static_field.dart.weak.modular.expect
new file mode 100644
index 0000000..7ebd7ea
--- /dev/null
+++ b/pkg/front_end/testcases/general/check_deferred_read_static_field.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "deferred_lib.dart" as def;
+
+import "org-dartlang-testcase:///deferred_lib.dart" deferred as lib;
+
+static method main() → dynamic {}
+static method test() → dynamic {
+  core::print(let final dynamic #t1 = CheckLibraryIsLoaded(lib) in def::C::y);
+}
+
+library;
+import self as def;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::int* y = 1;
+  synthetic constructor •() → def::C*
+    : super core::Object::•()
+    ;
+  static method m() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* x = 0;
+static method m(dynamic x) → dynamic
+  return null;
diff --git a/pkg/front_end/testcases/general/check_deferred_read_type.dart.weak.modular.expect b/pkg/front_end/testcases/general/check_deferred_read_type.dart.weak.modular.expect
new file mode 100644
index 0000000..efb9d56
--- /dev/null
+++ b/pkg/front_end/testcases/general/check_deferred_read_type.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///deferred_lib.dart" deferred as lib;
+
+static method main() → dynamic {}
+static method test() → dynamic {
+  core::print(let final dynamic #t1 = CheckLibraryIsLoaded(lib) in #C1);
+}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::int* y = 1;
+  synthetic constructor •() → self2::C*
+    : super core::Object::•()
+    ;
+  static method m() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* x = 0;
+static method m(dynamic x) → dynamic
+  return null;
+
+constants  {
+  #C1 = TypeLiteralConstant(self2::C*)
+}
diff --git a/pkg/front_end/testcases/general/check_deferred_static_method_call.dart.weak.modular.expect b/pkg/front_end/testcases/general/check_deferred_static_method_call.dart.weak.modular.expect
new file mode 100644
index 0000000..2fb6711
--- /dev/null
+++ b/pkg/front_end/testcases/general/check_deferred_static_method_call.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "deferred_lib.dart" as def;
+
+import "org-dartlang-testcase:///deferred_lib.dart" deferred as lib;
+
+static method main() → dynamic {}
+static method test() → dynamic {
+  core::print(let final dynamic #t1 = CheckLibraryIsLoaded(lib) in def::C::m());
+}
+
+library;
+import self as def;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::int* y = 1;
+  synthetic constructor •() → def::C*
+    : super core::Object::•()
+    ;
+  static method m() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* x = 0;
+static method m(dynamic x) → dynamic
+  return null;
diff --git a/pkg/front_end/testcases/general/check_deferred_type_declaration.dart.weak.modular.expect b/pkg/front_end/testcases/general/check_deferred_type_declaration.dart.weak.modular.expect
new file mode 100644
index 0000000..1189c30
--- /dev/null
+++ b/pkg/front_end/testcases/general/check_deferred_type_declaration.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/check_deferred_type_declaration.dart:9:3: Error: The type 'C' is deferred loaded via prefix 'lib' and can't be used as a type annotation.
+//  - 'C' is from 'pkg/front_end/testcases/general/deferred_lib.dart'.
+// Try removing 'deferred' from the import of 'lib' or use a supertype of 'C' that isn't deferred.
+//   lib.C x = null;
+//   ^^^^^
+//
+import self as self;
+
+import "org-dartlang-testcase:///deferred_lib.dart" deferred as lib;
+
+static method main() → dynamic
+  return self::test();
+static method test() → dynamic {
+  invalid-type x = null;
+}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::int* y = 1;
+  synthetic constructor •() → self2::C*
+    : super core::Object::•()
+    ;
+  static method m() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* x = 0;
+static method m(dynamic x) → dynamic
+  return null;
diff --git a/pkg/front_end/testcases/general/circularity-via-initializing-formal.dart.weak.modular.expect b/pkg/front_end/testcases/general/circularity-via-initializing-formal.dart.weak.modular.expect
new file mode 100644
index 0000000..80172a1
--- /dev/null
+++ b/pkg/front_end/testcases/general/circularity-via-initializing-formal.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/circularity-via-initializing-formal.dart:15:3: Error: Can't infer the type of 'C._circular': circularity found during type inference.
+// Specify the type explicitly.
+//   C._circular(this.f);
+//   ^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field self::C* f = new self::C::_circular(null);
+  constructor _circular(self::C* f) → self::C*
+    : self::C::f = f, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C* x = new self::C::_circular(null);
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/classes.dart.weak.modular.expect b/pkg/front_end/testcases/general/classes.dart.weak.modular.expect
new file mode 100644
index 0000000..288e237
--- /dev/null
+++ b/pkg/front_end/testcases/general/classes.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  final field core::int* x;
+  final field core::int* y;
+  constructor •(core::int* y) → self::A*
+    : self::A::y = y, self::A::x = 42, super core::Object::•()
+    ;
+  method method() → dynamic {
+    core::print("A.method x: ${this.{self::A::x}{core::int*}} y: ${this.{self::A::y}{core::int*}}");
+    core::print(this);
+    core::print(this.{self::A::runtimeType}{core::Type*});
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  constructor •(dynamic x) → self::B*
+    : super self::A::•(x as{TypeError,ForDynamic} core::int*)
+    ;
+  method method() → dynamic {
+    core::print("B.method x: ${this.{self::A::x}{core::int*}} y: ${this.{self::A::y}{core::int*}}");
+    super.{self::A::method}();
+  }
+}
+static method main() → dynamic {
+  self::A* a = new self::A::•(87);
+  self::B* b = new self::B::•(117);
+  a.{self::A::method}(){() →* dynamic};
+  b.{self::B::method}(){() →* dynamic};
+}
diff --git a/pkg/front_end/testcases/general/clone_function_type.dart.weak.modular.expect b/pkg/front_end/testcases/general/clone_function_type.dart.weak.modular.expect
new file mode 100644
index 0000000..7453dc4
--- /dev/null
+++ b/pkg/front_end/testcases/general/clone_function_type.dart.weak.modular.expect
@@ -0,0 +1,1425 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/clone_function_type.dart:22:51: Error: Expected an identifier, but got '}'.
+// Try inserting an identifier before '}'.
+// class Fm1<Z> extends Object with Am1<Function({int}), Z> {}
+//                                                   ^
+//
+// pkg/front_end/testcases/general/clone_function_type.dart:46:45: Error: Expected an identifier, but got '}'.
+// Try inserting an identifier before '}'.
+// class Qm1<Z> = Object with Am1<Function({int}), Z>;
+//                                             ^
+//
+// pkg/front_end/testcases/general/clone_function_type.dart:77:51: Error: Expected an identifier, but got '}'.
+// Try inserting an identifier before '}'.
+// class Fm2<Z> extends Object with Am2<Function({int}), Z> {}
+//                                                   ^
+//
+// pkg/front_end/testcases/general/clone_function_type.dart:105:45: Error: Expected an identifier, but got '}'.
+// Try inserting an identifier before '}'.
+// class Qm2<Z> = Object with Am2<Function({int}), Z>;
+//                                             ^
+//
+// pkg/front_end/testcases/general/clone_function_type.dart:134:28: Error: Expected an identifier, but got '}'.
+// Try inserting an identifier before '}'.
+// typedef TdF = Function({int});
+//                            ^
+//
+// pkg/front_end/testcases/general/clone_function_type.dart:190:34: Error: Expected an identifier, but got '}'.
+// Try inserting an identifier before '}'.
+// class Ef1<X extends Function({int})> {
+//                                  ^
+//
+// pkg/front_end/testcases/general/clone_function_type.dart:67:7: Error: Type argument 'dynamic Function(int)' doesn't conform to the bound 'dynamic Function()' of the type variable 'X' on 'Am2' in the supertype 'Am2' of class 'Object with Am2'.
+// Try changing type arguments so that they conform to the bounds.
+// class Bm2<Z> extends Object with Am2<Function(int), Z> {}
+//       ^
+// pkg/front_end/testcases/general/clone_function_type.dart:64:11: Context: This is the type variable whose bound isn't conformed to.
+// class Am2<X extends Function(), Y> {}
+//           ^
+//
+// pkg/front_end/testcases/general/clone_function_type.dart:70:7: Error: Type argument 'dynamic Function(int)' doesn't conform to the bound 'dynamic Function()' of the type variable 'X' on 'Am2' in the supertype 'Am2' of class 'Object with Am2'.
+// Try changing type arguments so that they conform to the bounds.
+// class Cm2<Z> extends Object with Am2<Function(int x), Z> {}
+//       ^
+// pkg/front_end/testcases/general/clone_function_type.dart:64:11: Context: This is the type variable whose bound isn't conformed to.
+// class Am2<X extends Function(), Y> {}
+//           ^
+//
+// pkg/front_end/testcases/general/clone_function_type.dart:86:7: Error: Type argument 'Function' doesn't conform to the bound 'dynamic Function()' of the type variable 'X' on 'Am2' in the supertype 'Am2' of class 'Object with Am2'.
+//  - 'Function' is from 'dart:core'.
+// Try changing type arguments so that they conform to the bounds.
+// class Jm2<Z> extends Object with Am2<Function, Z> {}
+//       ^
+// pkg/front_end/testcases/general/clone_function_type.dart:64:11: Context: This is the type variable whose bound isn't conformed to.
+// class Am2<X extends Function(), Y> {}
+//           ^
+//
+// pkg/front_end/testcases/general/clone_function_type.dart:89:7: Error: Type argument 'dynamic Function(Function)' doesn't conform to the bound 'dynamic Function()' of the type variable 'X' on 'Am2' in the supertype 'Am2' of class 'Object with Am2'.
+//  - 'Function' is from 'dart:core'.
+// Try changing type arguments so that they conform to the bounds.
+// class Km2<Z> extends Object with Am2<Function(Function Function), Z> {}
+//       ^
+// pkg/front_end/testcases/general/clone_function_type.dart:64:11: Context: This is the type variable whose bound isn't conformed to.
+// class Am2<X extends Function(), Y> {}
+//           ^
+//
+// pkg/front_end/testcases/general/clone_function_type.dart:95:7: Error: Type argument 'dynamic Function(int)' doesn't conform to the bound 'dynamic Function()' of the type variable 'X' on 'Am2' in the supertype 'Am2' of class 'Mm2'.
+// Try changing type arguments so that they conform to the bounds.
+// class Mm2<Z> = Object with Am2<Function(int), Z>;
+//       ^
+// pkg/front_end/testcases/general/clone_function_type.dart:64:11: Context: This is the type variable whose bound isn't conformed to.
+// class Am2<X extends Function(), Y> {}
+//           ^
+//
+// pkg/front_end/testcases/general/clone_function_type.dart:98:7: Error: Type argument 'dynamic Function(int)' doesn't conform to the bound 'dynamic Function()' of the type variable 'X' on 'Am2' in the supertype 'Am2' of class 'Nm2'.
+// Try changing type arguments so that they conform to the bounds.
+// class Nm2<Z> = Object with Am2<Function(int x), Z>;
+//       ^
+// pkg/front_end/testcases/general/clone_function_type.dart:64:11: Context: This is the type variable whose bound isn't conformed to.
+// class Am2<X extends Function(), Y> {}
+//           ^
+//
+// pkg/front_end/testcases/general/clone_function_type.dart:114:7: Error: Type argument 'Function' doesn't conform to the bound 'dynamic Function()' of the type variable 'X' on 'Am2' in the supertype 'Am2' of class 'Um2'.
+//  - 'Function' is from 'dart:core'.
+// Try changing type arguments so that they conform to the bounds.
+// class Um2<Z> = Object with Am2<Function, Z>;
+//       ^
+// pkg/front_end/testcases/general/clone_function_type.dart:64:11: Context: This is the type variable whose bound isn't conformed to.
+// class Am2<X extends Function(), Y> {}
+//           ^
+//
+// pkg/front_end/testcases/general/clone_function_type.dart:117:7: Error: Type argument 'dynamic Function(Function)' doesn't conform to the bound 'dynamic Function()' of the type variable 'X' on 'Am2' in the supertype 'Am2' of class 'Vm2'.
+//  - 'Function' is from 'dart:core'.
+// Try changing type arguments so that they conform to the bounds.
+// class Vm2<Z> = Object with Am2<Function(Function Function), Z>;
+//       ^
+// pkg/front_end/testcases/general/clone_function_type.dart:64:11: Context: This is the type variable whose bound isn't conformed to.
+// class Am2<X extends Function(), Y> {}
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef TdB = (core::int*) →* dynamic;
+typedef TdC = (core::int*) →* dynamic;
+typedef TdD = () →* core::int*;
+typedef TdE = () →* dynamic;
+typedef TdF = () →* dynamic;
+typedef TdG = ({x: core::int*}) →* dynamic;
+typedef TdH = ([core::int*]) →* dynamic;
+typedef TdI = ([core::int*]) →* dynamic;
+typedef TdJ = (core::Function*) →* dynamic;
+typedef TdK = () →* (() →* core::Function*) →* dynamic;
+class Am1<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Am1<self::Am1::X*, self::Am1::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Bm1&Object&Am1<Z extends core::Object* = dynamic> = core::Object with self::Am1<(core::int*) →* dynamic, self::_Bm1&Object&Am1::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Bm1&Object&Am1<self::_Bm1&Object&Am1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bm1<Z extends core::Object* = dynamic> extends self::_Bm1&Object&Am1<self::Bm1::Z*> {
+  synthetic constructor •() → self::Bm1<self::Bm1::Z*>*
+    : super self::_Bm1&Object&Am1::•()
+    ;
+}
+abstract class _Cm1&Object&Am1<Z extends core::Object* = dynamic> = core::Object with self::Am1<(core::int*) →* dynamic, self::_Cm1&Object&Am1::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Cm1&Object&Am1<self::_Cm1&Object&Am1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Cm1<Z extends core::Object* = dynamic> extends self::_Cm1&Object&Am1<self::Cm1::Z*> {
+  synthetic constructor •() → self::Cm1<self::Cm1::Z*>*
+    : super self::_Cm1&Object&Am1::•()
+    ;
+}
+abstract class _Dm1&Object&Am1<Z extends core::Object* = dynamic> = core::Object with self::Am1<() →* core::int*, self::_Dm1&Object&Am1::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Dm1&Object&Am1<self::_Dm1&Object&Am1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Dm1<Z extends core::Object* = dynamic> extends self::_Dm1&Object&Am1<self::Dm1::Z*> {
+  synthetic constructor •() → self::Dm1<self::Dm1::Z*>*
+    : super self::_Dm1&Object&Am1::•()
+    ;
+}
+abstract class _Em1&Object&Am1<Z extends core::Object* = dynamic> = core::Object with self::Am1<() →* dynamic, self::_Em1&Object&Am1::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Em1&Object&Am1<self::_Em1&Object&Am1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Em1<Z extends core::Object* = dynamic> extends self::_Em1&Object&Am1<self::Em1::Z*> {
+  synthetic constructor •() → self::Em1<self::Em1::Z*>*
+    : super self::_Em1&Object&Am1::•()
+    ;
+}
+abstract class _Fm1&Object&Am1<Z extends core::Object* = dynamic> = core::Object with self::Am1<() →* dynamic, self::_Fm1&Object&Am1::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Fm1&Object&Am1<self::_Fm1&Object&Am1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Fm1<Z extends core::Object* = dynamic> extends self::_Fm1&Object&Am1<self::Fm1::Z*> {
+  synthetic constructor •() → self::Fm1<self::Fm1::Z*>*
+    : super self::_Fm1&Object&Am1::•()
+    ;
+}
+abstract class _Gm1&Object&Am1<Z extends core::Object* = dynamic> = core::Object with self::Am1<({x: core::int*}) →* dynamic, self::_Gm1&Object&Am1::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Gm1&Object&Am1<self::_Gm1&Object&Am1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Gm1<Z extends core::Object* = dynamic> extends self::_Gm1&Object&Am1<self::Gm1::Z*> {
+  synthetic constructor •() → self::Gm1<self::Gm1::Z*>*
+    : super self::_Gm1&Object&Am1::•()
+    ;
+}
+abstract class _Hm1&Object&Am1<Z extends core::Object* = dynamic> = core::Object with self::Am1<([core::int*]) →* dynamic, self::_Hm1&Object&Am1::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Hm1&Object&Am1<self::_Hm1&Object&Am1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Hm1<Z extends core::Object* = dynamic> extends self::_Hm1&Object&Am1<self::Hm1::Z*> {
+  synthetic constructor •() → self::Hm1<self::Hm1::Z*>*
+    : super self::_Hm1&Object&Am1::•()
+    ;
+}
+abstract class _Im1&Object&Am1<Z extends core::Object* = dynamic> = core::Object with self::Am1<([core::int*]) →* dynamic, self::_Im1&Object&Am1::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Im1&Object&Am1<self::_Im1&Object&Am1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Im1<Z extends core::Object* = dynamic> extends self::_Im1&Object&Am1<self::Im1::Z*> {
+  synthetic constructor •() → self::Im1<self::Im1::Z*>*
+    : super self::_Im1&Object&Am1::•()
+    ;
+}
+abstract class _Jm1&Object&Am1<Z extends core::Object* = dynamic> = core::Object with self::Am1<core::Function*, self::_Jm1&Object&Am1::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Jm1&Object&Am1<self::_Jm1&Object&Am1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Jm1<Z extends core::Object* = dynamic> extends self::_Jm1&Object&Am1<self::Jm1::Z*> {
+  synthetic constructor •() → self::Jm1<self::Jm1::Z*>*
+    : super self::_Jm1&Object&Am1::•()
+    ;
+}
+abstract class _Km1&Object&Am1<Z extends core::Object* = dynamic> = core::Object with self::Am1<(core::Function*) →* dynamic, self::_Km1&Object&Am1::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Km1&Object&Am1<self::_Km1&Object&Am1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Km1<Z extends core::Object* = dynamic> extends self::_Km1&Object&Am1<self::Km1::Z*> {
+  synthetic constructor •() → self::Km1<self::Km1::Z*>*
+    : super self::_Km1&Object&Am1::•()
+    ;
+}
+abstract class _Lm1&Object&Am1<Z extends core::Object* = dynamic> = core::Object with self::Am1<() →* (() →* core::Function*) →* dynamic, self::_Lm1&Object&Am1::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Lm1&Object&Am1<self::_Lm1&Object&Am1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Lm1<Z extends core::Object* = dynamic> extends self::_Lm1&Object&Am1<self::Lm1::Z*> {
+  synthetic constructor •() → self::Lm1<self::Lm1::Z*>*
+    : super self::_Lm1&Object&Am1::•()
+    ;
+}
+class Mm1<Z extends core::Object* = dynamic> = core::Object with self::Am1<(core::int*) →* dynamic, self::Mm1::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Mm1<self::Mm1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Nm1<Z extends core::Object* = dynamic> = core::Object with self::Am1<(core::int*) →* dynamic, self::Nm1::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Nm1<self::Nm1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Om1<Z extends core::Object* = dynamic> = core::Object with self::Am1<() →* core::int*, self::Om1::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Om1<self::Om1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Pm1<Z extends core::Object* = dynamic> = core::Object with self::Am1<() →* dynamic, self::Pm1::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Pm1<self::Pm1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Qm1<Z extends core::Object* = dynamic> = core::Object with self::Am1<() →* dynamic, self::Qm1::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Qm1<self::Qm1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Rm1<Z extends core::Object* = dynamic> = core::Object with self::Am1<({x: core::int*}) →* dynamic, self::Rm1::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Rm1<self::Rm1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Sm1<Z extends core::Object* = dynamic> = core::Object with self::Am1<([core::int*]) →* dynamic, self::Sm1::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Sm1<self::Sm1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Tm1<Z extends core::Object* = dynamic> = core::Object with self::Am1<([core::int*]) →* dynamic, self::Tm1::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Tm1<self::Tm1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Um1<Z extends core::Object* = dynamic> = core::Object with self::Am1<core::Function*, self::Um1::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Um1<self::Um1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Vm1<Z extends core::Object* = dynamic> = core::Object with self::Am1<(core::Function*) →* dynamic, self::Vm1::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Vm1<self::Vm1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Wm1<Z extends core::Object* = dynamic> = core::Object with self::Am1<() →* (() →* core::Function*) →* dynamic, self::Wm1::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Wm1<self::Wm1::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Am2<X extends () →* dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Am2<self::Am2::X*, self::Am2::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Bm2&Object&Am2<Z extends core::Object* = dynamic> = core::Object with self::Am2<(core::int*) →* dynamic, self::_Bm2&Object&Am2::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Bm2&Object&Am2<self::_Bm2&Object&Am2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bm2<Z extends core::Object* = dynamic> extends self::_Bm2&Object&Am2<self::Bm2::Z*> {
+  synthetic constructor •() → self::Bm2<self::Bm2::Z*>*
+    : super self::_Bm2&Object&Am2::•()
+    ;
+}
+abstract class _Cm2&Object&Am2<Z extends core::Object* = dynamic> = core::Object with self::Am2<(core::int*) →* dynamic, self::_Cm2&Object&Am2::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Cm2&Object&Am2<self::_Cm2&Object&Am2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Cm2<Z extends core::Object* = dynamic> extends self::_Cm2&Object&Am2<self::Cm2::Z*> {
+  synthetic constructor •() → self::Cm2<self::Cm2::Z*>*
+    : super self::_Cm2&Object&Am2::•()
+    ;
+}
+abstract class _Dm2&Object&Am2<Z extends core::Object* = dynamic> = core::Object with self::Am2<() →* core::int*, self::_Dm2&Object&Am2::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Dm2&Object&Am2<self::_Dm2&Object&Am2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Dm2<Z extends core::Object* = dynamic> extends self::_Dm2&Object&Am2<self::Dm2::Z*> {
+  synthetic constructor •() → self::Dm2<self::Dm2::Z*>*
+    : super self::_Dm2&Object&Am2::•()
+    ;
+}
+abstract class _Em2&Object&Am2<Z extends core::Object* = dynamic> = core::Object with self::Am2<() →* dynamic, self::_Em2&Object&Am2::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Em2&Object&Am2<self::_Em2&Object&Am2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Em2<Z extends core::Object* = dynamic> extends self::_Em2&Object&Am2<self::Em2::Z*> {
+  synthetic constructor •() → self::Em2<self::Em2::Z*>*
+    : super self::_Em2&Object&Am2::•()
+    ;
+}
+abstract class _Fm2&Object&Am2<Z extends core::Object* = dynamic> = core::Object with self::Am2<() →* dynamic, self::_Fm2&Object&Am2::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Fm2&Object&Am2<self::_Fm2&Object&Am2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Fm2<Z extends core::Object* = dynamic> extends self::_Fm2&Object&Am2<self::Fm2::Z*> {
+  synthetic constructor •() → self::Fm2<self::Fm2::Z*>*
+    : super self::_Fm2&Object&Am2::•()
+    ;
+}
+abstract class _Gm2&Object&Am2<Z extends core::Object* = dynamic> = core::Object with self::Am2<({x: core::int*}) →* dynamic, self::_Gm2&Object&Am2::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Gm2&Object&Am2<self::_Gm2&Object&Am2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Gm2<Z extends core::Object* = dynamic> extends self::_Gm2&Object&Am2<self::Gm2::Z*> {
+  synthetic constructor •() → self::Gm2<self::Gm2::Z*>*
+    : super self::_Gm2&Object&Am2::•()
+    ;
+}
+abstract class _Hm2&Object&Am2<Z extends core::Object* = dynamic> = core::Object with self::Am2<([core::int*]) →* dynamic, self::_Hm2&Object&Am2::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Hm2&Object&Am2<self::_Hm2&Object&Am2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Hm2<Z extends core::Object* = dynamic> extends self::_Hm2&Object&Am2<self::Hm2::Z*> {
+  synthetic constructor •() → self::Hm2<self::Hm2::Z*>*
+    : super self::_Hm2&Object&Am2::•()
+    ;
+}
+abstract class _Im2&Object&Am2<Z extends core::Object* = dynamic> = core::Object with self::Am2<([core::int*]) →* dynamic, self::_Im2&Object&Am2::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Im2&Object&Am2<self::_Im2&Object&Am2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Im2<Z extends core::Object* = dynamic> extends self::_Im2&Object&Am2<self::Im2::Z*> {
+  synthetic constructor •() → self::Im2<self::Im2::Z*>*
+    : super self::_Im2&Object&Am2::•()
+    ;
+}
+abstract class _Jm2&Object&Am2<Z extends core::Object* = dynamic> = core::Object with self::Am2<core::Function*, self::_Jm2&Object&Am2::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Jm2&Object&Am2<self::_Jm2&Object&Am2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Jm2<Z extends core::Object* = dynamic> extends self::_Jm2&Object&Am2<self::Jm2::Z*> {
+  synthetic constructor •() → self::Jm2<self::Jm2::Z*>*
+    : super self::_Jm2&Object&Am2::•()
+    ;
+}
+abstract class _Km2&Object&Am2<Z extends core::Object* = dynamic> = core::Object with self::Am2<(core::Function*) →* dynamic, self::_Km2&Object&Am2::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Km2&Object&Am2<self::_Km2&Object&Am2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Km2<Z extends core::Object* = dynamic> extends self::_Km2&Object&Am2<self::Km2::Z*> {
+  synthetic constructor •() → self::Km2<self::Km2::Z*>*
+    : super self::_Km2&Object&Am2::•()
+    ;
+}
+abstract class _Lm2&Object&Am2<Z extends core::Object* = dynamic> = core::Object with self::Am2<() →* (() →* core::Function*) →* dynamic, self::_Lm2&Object&Am2::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Lm2&Object&Am2<self::_Lm2&Object&Am2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Lm2<Z extends core::Object* = dynamic> extends self::_Lm2&Object&Am2<self::Lm2::Z*> {
+  synthetic constructor •() → self::Lm2<self::Lm2::Z*>*
+    : super self::_Lm2&Object&Am2::•()
+    ;
+}
+class Mm2<Z extends core::Object* = dynamic> = core::Object with self::Am2<(core::int*) →* dynamic, self::Mm2::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Mm2<self::Mm2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Nm2<Z extends core::Object* = dynamic> = core::Object with self::Am2<(core::int*) →* dynamic, self::Nm2::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Nm2<self::Nm2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Om2<Z extends core::Object* = dynamic> = core::Object with self::Am2<() →* core::int*, self::Om2::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Om2<self::Om2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Pm2<Z extends core::Object* = dynamic> = core::Object with self::Am2<() →* dynamic, self::Pm2::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Pm2<self::Pm2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Qm2<Z extends core::Object* = dynamic> = core::Object with self::Am2<() →* dynamic, self::Qm2::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Qm2<self::Qm2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Rm2<Z extends core::Object* = dynamic> = core::Object with self::Am2<({x: core::int*}) →* dynamic, self::Rm2::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Rm2<self::Rm2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Sm2<Z extends core::Object* = dynamic> = core::Object with self::Am2<([core::int*]) →* dynamic, self::Sm2::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Sm2<self::Sm2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Tm2<Z extends core::Object* = dynamic> = core::Object with self::Am2<([core::int*]) →* dynamic, self::Tm2::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Tm2<self::Tm2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Um2<Z extends core::Object* = dynamic> = core::Object with self::Am2<core::Function*, self::Um2::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Um2<self::Um2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Vm2<Z extends core::Object* = dynamic> = core::Object with self::Am2<(core::Function*) →* dynamic, self::Vm2::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Vm2<self::Vm2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Wm2<Z extends core::Object* = dynamic> = core::Object with self::Am2<() →* (() →* core::Function*) →* dynamic, self::Wm2::Z*> /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Wm2<self::Wm2::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Am3<L extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Am3<self::Am3::L*, self::Am3::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Bm3&Object&Am3<Z extends core::Object* = dynamic> = core::Object with self::Am3<(core::int*) →* dynamic, self::_Bm3&Object&Am3::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Bm3&Object&Am3<self::_Bm3&Object&Am3::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bm3<Z extends core::Object* = dynamic> extends self::_Bm3&Object&Am3<self::Bm3::Z*> {
+  synthetic constructor •() → self::Bm3<self::Bm3::Z*>*
+    : super self::_Bm3&Object&Am3::•()
+    ;
+}
+abstract class _Cm3&Object&Am3<Z extends core::Object* = dynamic> = core::Object with self::Am3<(core::int*) →* dynamic, self::_Cm3&Object&Am3::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Cm3&Object&Am3<self::_Cm3&Object&Am3::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Cm3<Z extends core::Object* = dynamic> extends self::_Cm3&Object&Am3<self::Cm3::Z*> {
+  synthetic constructor •() → self::Cm3<self::Cm3::Z*>*
+    : super self::_Cm3&Object&Am3::•()
+    ;
+}
+abstract class _Dm3&Object&Am3<Z extends core::Object* = dynamic> = core::Object with self::Am3<() →* core::int*, self::_Dm3&Object&Am3::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Dm3&Object&Am3<self::_Dm3&Object&Am3::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Dm3<Z extends core::Object* = dynamic> extends self::_Dm3&Object&Am3<self::Dm3::Z*> {
+  synthetic constructor •() → self::Dm3<self::Dm3::Z*>*
+    : super self::_Dm3&Object&Am3::•()
+    ;
+}
+abstract class _Em3&Object&Am3<Z extends core::Object* = dynamic> = core::Object with self::Am3<() →* dynamic, self::_Em3&Object&Am3::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Em3&Object&Am3<self::_Em3&Object&Am3::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Em3<Z extends core::Object* = dynamic> extends self::_Em3&Object&Am3<self::Em3::Z*> {
+  synthetic constructor •() → self::Em3<self::Em3::Z*>*
+    : super self::_Em3&Object&Am3::•()
+    ;
+}
+abstract class _Fm3&Object&Am3<Z extends core::Object* = dynamic> = core::Object with self::Am3<() →* dynamic, self::_Fm3&Object&Am3::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Fm3&Object&Am3<self::_Fm3&Object&Am3::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Fm3<Z extends core::Object* = dynamic> extends self::_Fm3&Object&Am3<self::Fm3::Z*> {
+  synthetic constructor •() → self::Fm3<self::Fm3::Z*>*
+    : super self::_Fm3&Object&Am3::•()
+    ;
+}
+abstract class _Gm3&Object&Am3<Z extends core::Object* = dynamic> = core::Object with self::Am3<({x: core::int*}) →* dynamic, self::_Gm3&Object&Am3::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Gm3&Object&Am3<self::_Gm3&Object&Am3::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Gm3<Z extends core::Object* = dynamic> extends self::_Gm3&Object&Am3<self::Gm3::Z*> {
+  synthetic constructor •() → self::Gm3<self::Gm3::Z*>*
+    : super self::_Gm3&Object&Am3::•()
+    ;
+}
+abstract class _Hm3&Object&Am3<Z extends core::Object* = dynamic> = core::Object with self::Am3<([core::int*]) →* dynamic, self::_Hm3&Object&Am3::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Hm3&Object&Am3<self::_Hm3&Object&Am3::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Hm3<Z extends core::Object* = dynamic> extends self::_Hm3&Object&Am3<self::Hm3::Z*> {
+  synthetic constructor •() → self::Hm3<self::Hm3::Z*>*
+    : super self::_Hm3&Object&Am3::•()
+    ;
+}
+abstract class _Im3&Object&Am3<Z extends core::Object* = dynamic> = core::Object with self::Am3<([core::int*]) →* dynamic, self::_Im3&Object&Am3::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Im3&Object&Am3<self::_Im3&Object&Am3::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Im3<Z extends core::Object* = dynamic> extends self::_Im3&Object&Am3<self::Im3::Z*> {
+  synthetic constructor •() → self::Im3<self::Im3::Z*>*
+    : super self::_Im3&Object&Am3::•()
+    ;
+}
+abstract class _Jm3&Object&Am3<Z extends core::Object* = dynamic> = core::Object with self::Am3<(core::Function*) →* dynamic, self::_Jm3&Object&Am3::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Jm3&Object&Am3<self::_Jm3&Object&Am3::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Jm3<Z extends core::Object* = dynamic> extends self::_Jm3&Object&Am3<self::Jm3::Z*> {
+  synthetic constructor •() → self::Jm3<self::Jm3::Z*>*
+    : super self::_Jm3&Object&Am3::•()
+    ;
+}
+abstract class _Km3&Object&Am3<Z extends core::Object* = dynamic> = core::Object with self::Am3<() →* (() →* core::Function*) →* dynamic, self::_Km3&Object&Am3::Z*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Km3&Object&Am3<self::_Km3&Object&Am3::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Km3<Z extends core::Object* = dynamic> extends self::_Km3&Object&Am3<self::Km3::Z*> {
+  synthetic constructor •() → self::Km3<self::Km3::Z*>*
+    : super self::_Km3&Object&Am3::•()
+    ;
+}
+class Af1<X extends (core::int*) →* dynamic> extends core::Object {
+  static factory foo<X extends (core::int*) →* dynamic>() → self::Af1<self::Af1::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bf1<X extends (core::int*) →* dynamic> extends core::Object {
+  static factory foo<X extends (core::int*) →* dynamic>() → self::Bf1<self::Bf1::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Cf1<X extends () →* core::int*> extends core::Object {
+  static factory foo<X extends () →* core::int*>() → self::Cf1<self::Cf1::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Df1<X extends () →* dynamic> extends core::Object {
+  static factory foo<X extends () →* dynamic>() → self::Df1<self::Df1::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Ef1<X extends () →* dynamic> extends core::Object {
+  static factory foo<X extends () →* dynamic>() → self::Ef1<self::Ef1::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Ff1<X extends ({x: core::int*}) →* dynamic> extends core::Object {
+  static factory foo<X extends ({x: core::int*}) →* dynamic>() → self::Ff1<self::Ff1::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Gf1<X extends ([core::int*]) →* dynamic> extends core::Object {
+  static factory foo<X extends ([core::int*]) →* dynamic>() → self::Gf1<self::Gf1::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Hf1<X extends ([core::int*]) →* dynamic> extends core::Object {
+  static factory foo<X extends ([core::int*]) →* dynamic>() → self::Hf1<self::Hf1::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class If1<X extends core::Function*> extends core::Object {
+  static factory foo<X extends core::Function*>() → self::If1<self::If1::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Jf1<X extends (core::Function*) →* dynamic> extends core::Object {
+  static factory foo<X extends (core::Function*) →* dynamic>() → self::Jf1<self::Jf1::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Kf1<X extends () →* (() →* core::Function*) →* dynamic> extends core::Object {
+  static factory foo<X extends () →* (() →* core::Function*) →* dynamic>() → self::Kf1<self::Kf1::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bf2<X extends (core::int*) →* dynamic> extends core::Object {
+  static factory foo<X extends (core::int*) →* dynamic>() → self::Bf2<self::Bf2::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Cf2<X extends (core::int*) →* dynamic> extends core::Object {
+  static factory foo<X extends (core::int*) →* dynamic>() → self::Cf2<self::Cf2::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Df2<X extends () →* core::int*> extends core::Object {
+  static factory foo<X extends () →* core::int*>() → self::Df2<self::Df2::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Ef2<X extends () →* dynamic> extends core::Object {
+  static factory foo<X extends () →* dynamic>() → self::Ef2<self::Ef2::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Ff2<X extends () →* dynamic> extends core::Object {
+  static factory foo<X extends () →* dynamic>() → self::Ff2<self::Ff2::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Gf2<X extends ({x: core::int*}) →* dynamic> extends core::Object {
+  static factory foo<X extends ({x: core::int*}) →* dynamic>() → self::Gf2<self::Gf2::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Hf2<X extends ([core::int*]) →* dynamic> extends core::Object {
+  static factory foo<X extends ([core::int*]) →* dynamic>() → self::Hf2<self::Hf2::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class If2<X extends ([core::int*]) →* dynamic> extends core::Object {
+  static factory foo<X extends ([core::int*]) →* dynamic>() → self::If2<self::If2::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Jf2<X extends (core::Function*) →* dynamic> extends core::Object {
+  static factory foo<X extends (core::Function*) →* dynamic>() → self::Jf2<self::Jf2::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Kf2<X extends () →* (() →* core::Function*) →* dynamic> extends core::Object {
+  static factory foo<X extends () →* (() →* core::Function*) →* dynamic>() → self::Kf2<self::Kf2::foo::X*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/closure.dart.weak.modular.expect b/pkg/front_end/testcases/general/closure.dart.weak.modular.expect
new file mode 100644
index 0000000..2d530e8
--- /dev/null
+++ b/pkg/front_end/testcases/general/closure.dart.weak.modular.expect
@@ -0,0 +1,47 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  field self::Bar* _field = new self::Bar::•();
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar extends core::Object {
+  synthetic constructor •() → self::Bar*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method useCallback(dynamic callback) → dynamic {
+  dynamic _ = callback{dynamic}.call();
+}
+static method main() → dynamic {
+  dynamic x;
+  function inner() → self::Foo* {
+    x = new self::Foo::•();
+    return new self::Foo::•();
+  }
+  self::useCallback(inner);
+  self::Bar* _ = inner(){() →* self::Foo*}.{self::Foo::_field}{self::Bar*};
+}
diff --git a/pkg/front_end/testcases/general/co19_language_metadata_syntax_t04.dart.weak.modular.expect b/pkg/front_end/testcases/general/co19_language_metadata_syntax_t04.dart.weak.modular.expect
new file mode 100644
index 0000000..58cf612
--- /dev/null
+++ b/pkg/front_end/testcases/general/co19_language_metadata_syntax_t04.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/co19_language_metadata_syntax_t04.dart:21:1: Error: Expected '{' before this.
+// class B {}
+// ^^^^^
+//
+// pkg/front_end/testcases/general/co19_language_metadata_syntax_t04.dart:20:1: Error: 'A' is already declared in this scope.
+// A()
+// ^
+// pkg/front_end/testcases/general/co19_language_metadata_syntax_t04.dart:16:7: Context: Previous declaration of 'A'.
+// class A {
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/complex_class_hierarchy.dart.weak.modular.expect b/pkg/front_end/testcases/general/complex_class_hierarchy.dart.weak.modular.expect
new file mode 100644
index 0000000..79836e1
--- /dev/null
+++ b/pkg/front_end/testcases/general/complex_class_hierarchy.dart.weak.modular.expect
@@ -0,0 +1,210 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+}
+class G<T extends self::A*> extends core::Object {
+  synthetic constructor •() → self::G<self::G::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class GB extends self::G<self::B*> {
+  synthetic constructor •() → self::GB*
+    : super self::G::•()
+    ;
+}
+class GC extends self::G<self::C*> {
+  synthetic constructor •() → self::GC*
+    : super self::G::•()
+    ;
+}
+class GD extends self::G<self::D*> {
+  synthetic constructor •() → self::GD*
+    : super self::G::•()
+    ;
+}
+class X extends core::Object implements self::A {
+  synthetic constructor •() → self::X*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Y extends self::X {
+  synthetic constructor •() → self::Y*
+    : super self::X::•()
+    ;
+}
+class Z extends core::Object implements self::Y {
+  synthetic constructor •() → self::Z*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class W extends core::Object implements self::Z {
+  synthetic constructor •() → self::W*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class GX extends core::Object implements self::G<self::A*> {
+  synthetic constructor •() → self::GX*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class GY extends self::X implements self::GB {
+  synthetic constructor •() → self::GY*
+    : super self::X::•()
+    ;
+}
+class GZ extends core::Object implements self::Y, self::GC {
+  synthetic constructor •() → self::GZ*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class GW extends core::Object implements self::Z, self::GD {
+  synthetic constructor •() → self::GW*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class GU extends self::GW {
+  synthetic constructor •() → self::GU*
+    : super self::GW::•()
+    ;
+}
+class GV extends self::GU implements self::GW {
+  synthetic constructor •() → self::GV*
+    : super self::GU::•()
+    ;
+}
+class ARO<S extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::ARO<self::ARO::S*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class ARQ<T extends core::Object* = dynamic> extends core::Object implements self::ARO<self::ARQ::T*> {
+  synthetic constructor •() → self::ARQ<self::ARQ::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class ARN extends self::ARQ<self::A*> {
+  synthetic constructor •() → self::ARN*
+    : super self::ARQ::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/compound_binary_implicit_as.dart.weak.modular.expect b/pkg/front_end/testcases/general/compound_binary_implicit_as.dart.weak.modular.expect
new file mode 100644
index 0000000..19b1b00
--- /dev/null
+++ b/pkg/front_end/testcases/general/compound_binary_implicit_as.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::B* b) → self::A*
+    return new self::C::•();
+}
+class C extends self::A {
+  synthetic constructor •() → self::C*
+    : super self::A::•()
+    ;
+}
+static method main() → dynamic {
+  core::Map<core::int*, self::B*>* map = <core::int*, self::B*>{0: new self::B::•()};
+  try {
+    let final core::Map<core::int*, self::B*>* #t1 = map in let final core::int* #t2 = 0 in #t1.{core::Map::[]=}(#t2, #t1.{core::Map::[]}(#t2){(core::Object*) →* self::B*}.{self::B::+}(new self::B::•()){(self::B*) →* self::A*} as{TypeError} self::B*){(core::int*, self::B*) →* void};
+    throw "Expected type error";
+  }
+  on dynamic catch(final dynamic _) {
+  }
+}
diff --git a/pkg/front_end/testcases/general/conditional_import.dart.weak.modular.expect b/pkg/front_end/testcases/general/conditional_import.dart.weak.modular.expect
new file mode 100644
index 0000000..0ae3432
--- /dev/null
+++ b/pkg/front_end/testcases/general/conditional_import.dart.weak.modular.expect
@@ -0,0 +1,82 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/conditional_import.dart:18:11: Error: The getter 'readyState' isn't defined for the class 'HttpRequest'.
+//  - 'HttpRequest' is from 'dart:_http'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'readyState'.
+//   request.readyState; // error (from dart:html)
+//           ^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/conditional_import.dart:23:11: Error: The getter 'certificate' isn't defined for the class 'HttpRequest'.
+//  - 'HttpRequest' is from 'pkg/front_end/testcases/general/conditional_import.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'certificate'.
+//   request.certificate; // error
+//           ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/conditional_import.dart:24:11: Error: The getter 'response' isn't defined for the class 'HttpRequest'.
+//  - 'HttpRequest' is from 'pkg/front_end/testcases/general/conditional_import.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'response'.
+//   request.response; // error
+//           ^^^^^^^^
+//
+// pkg/front_end/testcases/general/conditional_import.dart:25:11: Error: The getter 'readyState' isn't defined for the class 'HttpRequest'.
+//  - 'HttpRequest' is from 'pkg/front_end/testcases/general/conditional_import.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'readyState'.
+//   request.readyState; // error
+//           ^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_http" as _ht;
+import "dart:io" as io;
+
+import "dart:io" as a;
+import "org-dartlang-testcase:///conditional_import.dart" as b;
+
+class HttpRequest extends core::Object {
+  synthetic constructor •() → self::HttpRequest
+    : super core::Object::•()
+    ;
+}
+static method testA(_ht::HttpRequest request) → dynamic {
+  request.{_ht::HttpRequest::certificate}{io::X509Certificate?};
+  request.{_ht::HttpRequest::response}{_ht::HttpResponse};
+  invalid-expression "pkg/front_end/testcases/general/conditional_import.dart:18:11: Error: The getter 'readyState' isn't defined for the class 'HttpRequest'.
+ - 'HttpRequest' is from 'dart:_http'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'readyState'.
+  request.readyState; // error (from dart:html)
+          ^^^^^^^^^^" in request{<unresolved>}.readyState;
+  request.{core::Object::hashCode}{core::int};
+}
+static method testB(self::HttpRequest request) → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/conditional_import.dart:23:11: Error: The getter 'certificate' isn't defined for the class 'HttpRequest'.
+ - 'HttpRequest' is from 'pkg/front_end/testcases/general/conditional_import.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'certificate'.
+  request.certificate; // error
+          ^^^^^^^^^^^" in request{<unresolved>}.certificate;
+  invalid-expression "pkg/front_end/testcases/general/conditional_import.dart:24:11: Error: The getter 'response' isn't defined for the class 'HttpRequest'.
+ - 'HttpRequest' is from 'pkg/front_end/testcases/general/conditional_import.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'response'.
+  request.response; // error
+          ^^^^^^^^" in request{<unresolved>}.response;
+  invalid-expression "pkg/front_end/testcases/general/conditional_import.dart:25:11: Error: The getter 'readyState' isn't defined for the class 'HttpRequest'.
+ - 'HttpRequest' is from 'pkg/front_end/testcases/general/conditional_import.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'readyState'.
+  request.readyState; // error
+          ^^^^^^^^^^" in request{<unresolved>}.readyState;
+  request.{core::Object::hashCode}{core::int};
+}
+static method main() → void {
+  self::expect(true, #C1);
+  self::expect(false, #C1);
+  self::expect(false, #C1);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = false
+}
diff --git a/pkg/front_end/testcases/general/const_redirect_to_nonconst.dart.weak.modular.expect b/pkg/front_end/testcases/general/const_redirect_to_nonconst.dart.weak.modular.expect
new file mode 100644
index 0000000..38baae2
--- /dev/null
+++ b/pkg/front_end/testcases/general/const_redirect_to_nonconst.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/const_redirect_to_nonconst.dart:12:21: Error: A constant constructor can't call a non-constant super constructor.
+//   const B() : super.bad();
+//                     ^^^
+//
+// pkg/front_end/testcases/general/const_redirect_to_nonconst.dart:6:20: Error: A constant constructor can't call a non-constant constructor.
+//   const A() : this.bad();
+//                    ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A
+    : this self::A::bad()
+    ;
+  constructor bad() → self::A
+    : super core::Object::•() {}
+}
+class B extends self::A /*hasConstConstructor*/  {
+  const constructor •() → self::B
+    : super self::A::bad()
+    ;
+}
+static method test() → dynamic {
+  core::print(invalid-expression "A constant constructor can't call a non-constant constructor.");
+  core::print(invalid-expression "A constant constructor can't call a non-constant super constructor.");
+}
+static method main() → dynamic {
+  core::print(new self::A::•());
+  core::print(new self::B::•());
+}
+
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///const_redirect_to_nonconst.dart:
+- A. (from org-dartlang-testcase:///const_redirect_to_nonconst.dart:6:9)
+- B. (from org-dartlang-testcase:///const_redirect_to_nonconst.dart:12:9)
diff --git a/pkg/front_end/testcases/general/constant_truncate.dart.weak.modular.expect b/pkg/front_end/testcases/general/constant_truncate.dart.weak.modular.expect
new file mode 100644
index 0000000..f87f7ba
--- /dev/null
+++ b/pkg/front_end/testcases/general/constant_truncate.dart.weak.modular.expect
@@ -0,0 +1,415 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:5:14: Error: Constant evaluation error:
+// const a0 = 0 ~/ 0; // error
+//              ^
+// pkg/front_end/testcases/general/constant_truncate.dart:5:14: Context: Binary operator '~/' on '0' requires non-zero divisor, but divisor was '0'.
+// const a0 = 0 ~/ 0; // error
+//              ^
+// pkg/front_end/testcases/general/constant_truncate.dart:5:7: Context: While analyzing:
+// const a0 = 0 ~/ 0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:6:16: Error: Constant evaluation error:
+// const a1 = 0.0 ~/ 0; // error
+//                ^
+// pkg/front_end/testcases/general/constant_truncate.dart:6:16: Context: Binary operator '~/' on '0.0' requires non-zero divisor, but divisor was '0'.
+// const a1 = 0.0 ~/ 0; // error
+//                ^
+// pkg/front_end/testcases/general/constant_truncate.dart:6:7: Context: While analyzing:
+// const a1 = 0.0 ~/ 0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:7:17: Error: Constant evaluation error:
+// const a2 = -0.0 ~/ 0; // error
+//                 ^
+// pkg/front_end/testcases/general/constant_truncate.dart:7:17: Context: Binary operator '~/' on '-0.0' requires non-zero divisor, but divisor was '0'.
+// const a2 = -0.0 ~/ 0; // error
+//                 ^
+// pkg/front_end/testcases/general/constant_truncate.dart:7:7: Context: While analyzing:
+// const a2 = -0.0 ~/ 0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:8:23: Error: Constant evaluation error:
+// const a3 = double.nan ~/ 0; // error
+//                       ^
+// pkg/front_end/testcases/general/constant_truncate.dart:8:23: Context: Binary operator '~/' on 'NaN' requires non-zero divisor, but divisor was '0'.
+// const a3 = double.nan ~/ 0; // error
+//                       ^
+// pkg/front_end/testcases/general/constant_truncate.dart:8:7: Context: While analyzing:
+// const a3 = double.nan ~/ 0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:9:28: Error: Constant evaluation error:
+// const a4 = double.infinity ~/ 0; // error
+//                            ^
+// pkg/front_end/testcases/general/constant_truncate.dart:9:28: Context: Binary operator '~/' on 'Infinity' requires non-zero divisor, but divisor was '0'.
+// const a4 = double.infinity ~/ 0; // error
+//                            ^
+// pkg/front_end/testcases/general/constant_truncate.dart:9:7: Context: While analyzing:
+// const a4 = double.infinity ~/ 0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:10:36: Error: Constant evaluation error:
+// const a5 = double.negativeInfinity ~/ 0; // error
+//                                    ^
+// pkg/front_end/testcases/general/constant_truncate.dart:10:36: Context: Binary operator '~/' on '-Infinity' requires non-zero divisor, but divisor was '0'.
+// const a5 = double.negativeInfinity ~/ 0; // error
+//                                    ^
+// pkg/front_end/testcases/general/constant_truncate.dart:10:7: Context: While analyzing:
+// const a5 = double.negativeInfinity ~/ 0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:12:14: Error: Constant evaluation error:
+// const b0 = 0 ~/ 0.0; // error
+//              ^
+// pkg/front_end/testcases/general/constant_truncate.dart:12:14: Context: Binary operator '~/' on '0' requires non-zero divisor, but divisor was '0'.
+// const b0 = 0 ~/ 0.0; // error
+//              ^
+// pkg/front_end/testcases/general/constant_truncate.dart:12:7: Context: While analyzing:
+// const b0 = 0 ~/ 0.0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:13:16: Error: Constant evaluation error:
+// const b1 = 0.0 ~/ 0.0; // error
+//                ^
+// pkg/front_end/testcases/general/constant_truncate.dart:13:16: Context: Binary operator '~/' on '0.0' requires non-zero divisor, but divisor was '0'.
+// const b1 = 0.0 ~/ 0.0; // error
+//                ^
+// pkg/front_end/testcases/general/constant_truncate.dart:13:7: Context: While analyzing:
+// const b1 = 0.0 ~/ 0.0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:14:17: Error: Constant evaluation error:
+// const b2 = -0.0 ~/ 0.0; // error
+//                 ^
+// pkg/front_end/testcases/general/constant_truncate.dart:14:17: Context: Binary operator '~/' on '-0.0' requires non-zero divisor, but divisor was '0'.
+// const b2 = -0.0 ~/ 0.0; // error
+//                 ^
+// pkg/front_end/testcases/general/constant_truncate.dart:14:7: Context: While analyzing:
+// const b2 = -0.0 ~/ 0.0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:15:23: Error: Constant evaluation error:
+// const b3 = double.nan ~/ 0.0; // error
+//                       ^
+// pkg/front_end/testcases/general/constant_truncate.dart:15:23: Context: Binary operator '~/' on 'NaN' requires non-zero divisor, but divisor was '0'.
+// const b3 = double.nan ~/ 0.0; // error
+//                       ^
+// pkg/front_end/testcases/general/constant_truncate.dart:15:7: Context: While analyzing:
+// const b3 = double.nan ~/ 0.0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:16:28: Error: Constant evaluation error:
+// const b4 = double.infinity ~/ 0.0; // error
+//                            ^
+// pkg/front_end/testcases/general/constant_truncate.dart:16:28: Context: Binary operator '~/' on 'Infinity' requires non-zero divisor, but divisor was '0'.
+// const b4 = double.infinity ~/ 0.0; // error
+//                            ^
+// pkg/front_end/testcases/general/constant_truncate.dart:16:7: Context: While analyzing:
+// const b4 = double.infinity ~/ 0.0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:17:36: Error: Constant evaluation error:
+// const b5 = double.negativeInfinity ~/ 0.0; // error
+//                                    ^
+// pkg/front_end/testcases/general/constant_truncate.dart:17:36: Context: Binary operator '~/' on '-Infinity' requires non-zero divisor, but divisor was '0'.
+// const b5 = double.negativeInfinity ~/ 0.0; // error
+//                                    ^
+// pkg/front_end/testcases/general/constant_truncate.dart:17:7: Context: While analyzing:
+// const b5 = double.negativeInfinity ~/ 0.0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:19:14: Error: Constant evaluation error:
+// const c0 = 0 ~/ -0.0; // error
+//              ^
+// pkg/front_end/testcases/general/constant_truncate.dart:19:14: Context: Binary operator '~/' on '0' requires non-zero divisor, but divisor was '0'.
+// const c0 = 0 ~/ -0.0; // error
+//              ^
+// pkg/front_end/testcases/general/constant_truncate.dart:19:7: Context: While analyzing:
+// const c0 = 0 ~/ -0.0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:20:16: Error: Constant evaluation error:
+// const c1 = 0.0 ~/ -0.0; // error
+//                ^
+// pkg/front_end/testcases/general/constant_truncate.dart:20:16: Context: Binary operator '~/' on '0.0' requires non-zero divisor, but divisor was '0'.
+// const c1 = 0.0 ~/ -0.0; // error
+//                ^
+// pkg/front_end/testcases/general/constant_truncate.dart:20:7: Context: While analyzing:
+// const c1 = 0.0 ~/ -0.0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:21:17: Error: Constant evaluation error:
+// const c2 = -0.0 ~/ -0.0; // error
+//                 ^
+// pkg/front_end/testcases/general/constant_truncate.dart:21:17: Context: Binary operator '~/' on '-0.0' requires non-zero divisor, but divisor was '0'.
+// const c2 = -0.0 ~/ -0.0; // error
+//                 ^
+// pkg/front_end/testcases/general/constant_truncate.dart:21:7: Context: While analyzing:
+// const c2 = -0.0 ~/ -0.0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:22:23: Error: Constant evaluation error:
+// const c3 = double.nan ~/ -0.0; // error
+//                       ^
+// pkg/front_end/testcases/general/constant_truncate.dart:22:23: Context: Binary operator '~/' on 'NaN' requires non-zero divisor, but divisor was '0'.
+// const c3 = double.nan ~/ -0.0; // error
+//                       ^
+// pkg/front_end/testcases/general/constant_truncate.dart:22:7: Context: While analyzing:
+// const c3 = double.nan ~/ -0.0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:23:28: Error: Constant evaluation error:
+// const c4 = double.infinity ~/ -0.0; // error
+//                            ^
+// pkg/front_end/testcases/general/constant_truncate.dart:23:28: Context: Binary operator '~/' on 'Infinity' requires non-zero divisor, but divisor was '0'.
+// const c4 = double.infinity ~/ -0.0; // error
+//                            ^
+// pkg/front_end/testcases/general/constant_truncate.dart:23:7: Context: While analyzing:
+// const c4 = double.infinity ~/ -0.0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:24:36: Error: Constant evaluation error:
+// const c5 = double.negativeInfinity ~/ -0.0; // error
+//                                    ^
+// pkg/front_end/testcases/general/constant_truncate.dart:24:36: Context: Binary operator '~/' on '-Infinity' requires non-zero divisor, but divisor was '0'.
+// const c5 = double.negativeInfinity ~/ -0.0; // error
+//                                    ^
+// pkg/front_end/testcases/general/constant_truncate.dart:24:7: Context: While analyzing:
+// const c5 = double.negativeInfinity ~/ -0.0; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:26:14: Error: Constant evaluation error:
+// const d0 = 0 ~/ double.nan; // error
+//              ^
+// pkg/front_end/testcases/general/constant_truncate.dart:26:14: Context: Binary operator '0 ~/ NaN' results is Infinity or NaN.
+// const d0 = 0 ~/ double.nan; // error
+//              ^
+// pkg/front_end/testcases/general/constant_truncate.dart:26:7: Context: While analyzing:
+// const d0 = 0 ~/ double.nan; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:27:16: Error: Constant evaluation error:
+// const d1 = 0.0 ~/ double.nan; // error
+//                ^
+// pkg/front_end/testcases/general/constant_truncate.dart:27:16: Context: Binary operator '0.0 ~/ NaN' results is Infinity or NaN.
+// const d1 = 0.0 ~/ double.nan; // error
+//                ^
+// pkg/front_end/testcases/general/constant_truncate.dart:27:7: Context: While analyzing:
+// const d1 = 0.0 ~/ double.nan; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:28:17: Error: Constant evaluation error:
+// const d2 = -0.0 ~/ double.nan; // error
+//                 ^
+// pkg/front_end/testcases/general/constant_truncate.dart:28:17: Context: Binary operator '-0.0 ~/ NaN' results is Infinity or NaN.
+// const d2 = -0.0 ~/ double.nan; // error
+//                 ^
+// pkg/front_end/testcases/general/constant_truncate.dart:28:7: Context: While analyzing:
+// const d2 = -0.0 ~/ double.nan; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:29:23: Error: Constant evaluation error:
+// const d3 = double.nan ~/ double.nan; // error
+//                       ^
+// pkg/front_end/testcases/general/constant_truncate.dart:29:23: Context: Binary operator 'NaN ~/ NaN' results is Infinity or NaN.
+// const d3 = double.nan ~/ double.nan; // error
+//                       ^
+// pkg/front_end/testcases/general/constant_truncate.dart:29:7: Context: While analyzing:
+// const d3 = double.nan ~/ double.nan; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:30:28: Error: Constant evaluation error:
+// const d4 = double.infinity ~/ double.nan; // error
+//                            ^
+// pkg/front_end/testcases/general/constant_truncate.dart:30:28: Context: Binary operator 'Infinity ~/ NaN' results is Infinity or NaN.
+// const d4 = double.infinity ~/ double.nan; // error
+//                            ^
+// pkg/front_end/testcases/general/constant_truncate.dart:30:7: Context: While analyzing:
+// const d4 = double.infinity ~/ double.nan; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:31:36: Error: Constant evaluation error:
+// const d5 = double.negativeInfinity ~/ double.nan; // error
+//                                    ^
+// pkg/front_end/testcases/general/constant_truncate.dart:31:36: Context: Binary operator '-Infinity ~/ NaN' results is Infinity or NaN.
+// const d5 = double.negativeInfinity ~/ double.nan; // error
+//                                    ^
+// pkg/front_end/testcases/general/constant_truncate.dart:31:7: Context: While analyzing:
+// const d5 = double.negativeInfinity ~/ double.nan; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:36:23: Error: Constant evaluation error:
+// const e3 = double.nan ~/ double.infinity; // error
+//                       ^
+// pkg/front_end/testcases/general/constant_truncate.dart:36:23: Context: Binary operator 'NaN ~/ Infinity' results is Infinity or NaN.
+// const e3 = double.nan ~/ double.infinity; // error
+//                       ^
+// pkg/front_end/testcases/general/constant_truncate.dart:36:7: Context: While analyzing:
+// const e3 = double.nan ~/ double.infinity; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:37:28: Error: Constant evaluation error:
+// const e4 = double.infinity ~/ double.infinity; // error
+//                            ^
+// pkg/front_end/testcases/general/constant_truncate.dart:37:28: Context: Binary operator 'Infinity ~/ Infinity' results is Infinity or NaN.
+// const e4 = double.infinity ~/ double.infinity; // error
+//                            ^
+// pkg/front_end/testcases/general/constant_truncate.dart:37:7: Context: While analyzing:
+// const e4 = double.infinity ~/ double.infinity; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:38:36: Error: Constant evaluation error:
+// const e5 = double.negativeInfinity ~/ double.infinity; // error
+//                                    ^
+// pkg/front_end/testcases/general/constant_truncate.dart:38:36: Context: Binary operator '-Infinity ~/ Infinity' results is Infinity or NaN.
+// const e5 = double.negativeInfinity ~/ double.infinity; // error
+//                                    ^
+// pkg/front_end/testcases/general/constant_truncate.dart:38:7: Context: While analyzing:
+// const e5 = double.negativeInfinity ~/ double.infinity; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:43:23: Error: Constant evaluation error:
+// const f3 = double.nan ~/ double.negativeInfinity; // error
+//                       ^
+// pkg/front_end/testcases/general/constant_truncate.dart:43:23: Context: Binary operator 'NaN ~/ -Infinity' results is Infinity or NaN.
+// const f3 = double.nan ~/ double.negativeInfinity; // error
+//                       ^
+// pkg/front_end/testcases/general/constant_truncate.dart:43:7: Context: While analyzing:
+// const f3 = double.nan ~/ double.negativeInfinity; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:44:28: Error: Constant evaluation error:
+// const f4 = double.infinity ~/ double.negativeInfinity; // error
+//                            ^
+// pkg/front_end/testcases/general/constant_truncate.dart:44:28: Context: Binary operator 'Infinity ~/ -Infinity' results is Infinity or NaN.
+// const f4 = double.infinity ~/ double.negativeInfinity; // error
+//                            ^
+// pkg/front_end/testcases/general/constant_truncate.dart:44:7: Context: While analyzing:
+// const f4 = double.infinity ~/ double.negativeInfinity; // error
+//       ^
+//
+// pkg/front_end/testcases/general/constant_truncate.dart:45:36: Error: Constant evaluation error:
+// const f5 = double.negativeInfinity ~/ double.negativeInfinity; // error
+//                                    ^
+// pkg/front_end/testcases/general/constant_truncate.dart:45:36: Context: Binary operator '-Infinity ~/ -Infinity' results is Infinity or NaN.
+// const f5 = double.negativeInfinity ~/ double.negativeInfinity; // error
+//                                    ^
+// pkg/front_end/testcases/general/constant_truncate.dart:45:7: Context: While analyzing:
+// const f5 = double.negativeInfinity ~/ double.negativeInfinity; // error
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+static const field core::int* a0 = invalid-expression "Binary operator '~/' on '0' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* a1 = invalid-expression "Binary operator '~/' on '0.0' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* a2 = invalid-expression "Binary operator '~/' on '-0.0' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* a3 = invalid-expression "Binary operator '~/' on 'NaN' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* a4 = invalid-expression "Binary operator '~/' on 'Infinity' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* a5 = invalid-expression "Binary operator '~/' on '-Infinity' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* b0 = invalid-expression "Binary operator '~/' on '0' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* b1 = invalid-expression "Binary operator '~/' on '0.0' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* b2 = invalid-expression "Binary operator '~/' on '-0.0' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* b3 = invalid-expression "Binary operator '~/' on 'NaN' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* b4 = invalid-expression "Binary operator '~/' on 'Infinity' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* b5 = invalid-expression "Binary operator '~/' on '-Infinity' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* c0 = invalid-expression "Binary operator '~/' on '0' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* c1 = invalid-expression "Binary operator '~/' on '0.0' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* c2 = invalid-expression "Binary operator '~/' on '-0.0' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* c3 = invalid-expression "Binary operator '~/' on 'NaN' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* c4 = invalid-expression "Binary operator '~/' on 'Infinity' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* c5 = invalid-expression "Binary operator '~/' on '-Infinity' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* d0 = invalid-expression "Binary operator '0 ~/ NaN' results is Infinity or NaN.";
+static const field core::int* d1 = invalid-expression "Binary operator '0.0 ~/ NaN' results is Infinity or NaN.";
+static const field core::int* d2 = invalid-expression "Binary operator '-0.0 ~/ NaN' results is Infinity or NaN.";
+static const field core::int* d3 = invalid-expression "Binary operator 'NaN ~/ NaN' results is Infinity or NaN.";
+static const field core::int* d4 = invalid-expression "Binary operator 'Infinity ~/ NaN' results is Infinity or NaN.";
+static const field core::int* d5 = invalid-expression "Binary operator '-Infinity ~/ NaN' results is Infinity or NaN.";
+static const field core::int* e0 = #C1;
+static const field core::int* e1 = #C1;
+static const field core::int* e2 = #C1;
+static const field core::int* e3 = invalid-expression "Binary operator 'NaN ~/ Infinity' results is Infinity or NaN.";
+static const field core::int* e4 = invalid-expression "Binary operator 'Infinity ~/ Infinity' results is Infinity or NaN.";
+static const field core::int* e5 = invalid-expression "Binary operator '-Infinity ~/ Infinity' results is Infinity or NaN.";
+static const field core::int* f0 = #C1;
+static const field core::int* f1 = #C1;
+static const field core::int* f2 = #C1;
+static const field core::int* f3 = invalid-expression "Binary operator 'NaN ~/ -Infinity' results is Infinity or NaN.";
+static const field core::int* f4 = invalid-expression "Binary operator 'Infinity ~/ -Infinity' results is Infinity or NaN.";
+static const field core::int* f5 = invalid-expression "Binary operator '-Infinity ~/ -Infinity' results is Infinity or NaN.";
+static method main() → dynamic {
+  self::test(0, 0, () → core::int* => invalid-expression "Binary operator '~/' on '0' requires non-zero divisor, but divisor was '0'.");
+  self::test(0.0, 0, () → core::int* => invalid-expression "Binary operator '~/' on '0.0' requires non-zero divisor, but divisor was '0'.");
+  self::test(0.0.{core::double::unary-}(){() →* core::double*}, 0, () → core::int* => invalid-expression "Binary operator '~/' on '-0.0' requires non-zero divisor, but divisor was '0'.");
+  self::test(#C2, 0, () → core::int* => invalid-expression "Binary operator '~/' on 'NaN' requires non-zero divisor, but divisor was '0'.");
+  self::test(#C3, 0, () → core::int* => invalid-expression "Binary operator '~/' on 'Infinity' requires non-zero divisor, but divisor was '0'.");
+  self::test(#C4, 0, () → core::int* => invalid-expression "Binary operator '~/' on '-Infinity' requires non-zero divisor, but divisor was '0'.");
+  self::test(0, 0.0, () → core::int* => invalid-expression "Binary operator '~/' on '0' requires non-zero divisor, but divisor was '0'.");
+  self::test(0.0, 0.0, () → core::int* => invalid-expression "Binary operator '~/' on '0.0' requires non-zero divisor, but divisor was '0'.");
+  self::test(0.0.{core::double::unary-}(){() →* core::double*}, 0.0, () → core::int* => invalid-expression "Binary operator '~/' on '-0.0' requires non-zero divisor, but divisor was '0'.");
+  self::test(#C2, 0.0, () → core::int* => invalid-expression "Binary operator '~/' on 'NaN' requires non-zero divisor, but divisor was '0'.");
+  self::test(#C3, 0.0, () → core::int* => invalid-expression "Binary operator '~/' on 'Infinity' requires non-zero divisor, but divisor was '0'.");
+  self::test(#C4, 0.0, () → core::int* => invalid-expression "Binary operator '~/' on '-Infinity' requires non-zero divisor, but divisor was '0'.");
+  self::test(0, 0.0.{core::double::unary-}(){() →* core::double*}, () → core::int* => invalid-expression "Binary operator '~/' on '0' requires non-zero divisor, but divisor was '0'.");
+  self::test(0.0, 0.0.{core::double::unary-}(){() →* core::double*}, () → core::int* => invalid-expression "Binary operator '~/' on '0.0' requires non-zero divisor, but divisor was '0'.");
+  self::test(0.0.{core::double::unary-}(){() →* core::double*}, 0.0.{core::double::unary-}(){() →* core::double*}, () → core::int* => invalid-expression "Binary operator '~/' on '-0.0' requires non-zero divisor, but divisor was '0'.");
+  self::test(#C2, 0.0.{core::double::unary-}(){() →* core::double*}, () → core::int* => invalid-expression "Binary operator '~/' on 'NaN' requires non-zero divisor, but divisor was '0'.");
+  self::test(#C3, 0.0.{core::double::unary-}(){() →* core::double*}, () → core::int* => invalid-expression "Binary operator '~/' on 'Infinity' requires non-zero divisor, but divisor was '0'.");
+  self::test(#C4, 0.0.{core::double::unary-}(){() →* core::double*}, () → core::int* => invalid-expression "Binary operator '~/' on '-Infinity' requires non-zero divisor, but divisor was '0'.");
+  self::test(0, #C2, () → core::int* => invalid-expression "Binary operator '0 ~/ NaN' results is Infinity or NaN.");
+  self::test(0.0, #C2, () → core::int* => invalid-expression "Binary operator '0.0 ~/ NaN' results is Infinity or NaN.");
+  self::test(0.0.{core::double::unary-}(){() →* core::double*}, #C2, () → core::int* => invalid-expression "Binary operator '-0.0 ~/ NaN' results is Infinity or NaN.");
+  self::test(#C2, #C2, () → core::int* => invalid-expression "Binary operator 'NaN ~/ NaN' results is Infinity or NaN.");
+  self::test(#C3, #C2, () → core::int* => invalid-expression "Binary operator 'Infinity ~/ NaN' results is Infinity or NaN.");
+  self::test(#C4, #C2, () → core::int* => invalid-expression "Binary operator '-Infinity ~/ NaN' results is Infinity or NaN.");
+  self::test(0, #C3, () → core::int* => #C1);
+  self::test(0.0, #C3, () → core::int* => #C1);
+  self::test(0.0.{core::double::unary-}(){() →* core::double*}, #C3, () → core::int* => #C1);
+  self::test(#C2, #C3, () → core::int* => invalid-expression "Binary operator 'NaN ~/ Infinity' results is Infinity or NaN.");
+  self::test(#C3, #C3, () → core::int* => invalid-expression "Binary operator 'Infinity ~/ Infinity' results is Infinity or NaN.");
+  self::test(#C4, #C3, () → core::int* => invalid-expression "Binary operator '-Infinity ~/ Infinity' results is Infinity or NaN.");
+  self::test(0, #C4, () → core::int* => #C1);
+  self::test(0.0, #C4, () → core::int* => #C1);
+  self::test(0.0.{core::double::unary-}(){() →* core::double*}, #C4, () → core::int* => #C1);
+  self::test(#C2, #C4, () → core::int* => invalid-expression "Binary operator 'NaN ~/ -Infinity' results is Infinity or NaN.");
+  self::test(#C3, #C4, () → core::int* => invalid-expression "Binary operator 'Infinity ~/ -Infinity' results is Infinity or NaN.");
+  self::test(#C4, #C4, () → core::int* => invalid-expression "Binary operator '-Infinity ~/ -Infinity' results is Infinity or NaN.");
+}
+static method test(core::num* a, core::num* b, () →* core::num* f) → void {
+  core::num* result;
+  try {
+    result = a.{core::num::~/}(b){(core::num*) →* core::int*};
+    core::print("${a} ~/ ${b} = ${result}");
+  }
+  on dynamic catch(final dynamic e) {
+    core::print("${a} ~/ ${b} throws ${e}");
+    self::throws(f);
+    return;
+  }
+  self::expect(f(){() →* core::num*}, result);
+}
+static method expect(dynamic expected, dynamic actual) → void {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual)) {
+    throw "Expected ${expected}, actual ${actual}";
+  }
+}
+static method throws(() →* core::num* f) → void {
+  try {
+    f(){() →* core::num*};
+  }
+  on dynamic catch(final dynamic e) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+constants  {
+  #C1 = 0
+  #C2 = NaN
+  #C3 = Infinity
+  #C4 = -Infinity
+}
diff --git a/pkg/front_end/testcases/general/constants/circularity.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/circularity.dart.weak.modular.expect
new file mode 100644
index 0000000..d9ec24f
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/circularity.dart.weak.modular.expect
@@ -0,0 +1,143 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/circularity.dart:37:34: Error: Constant evaluation error:
+//   const Class4({Class4 c = const Class4()});
+//                                  ^
+// pkg/front_end/testcases/general/constants/circularity.dart:37:34: Context: Constant expression depends on itself.
+//   const Class4({Class4 c = const Class4()});
+//                                  ^
+// pkg/front_end/testcases/general/constants/circularity.dart:37:24: Context: While analyzing:
+//   const Class4({Class4 c = const Class4()});
+//                        ^
+//
+// pkg/front_end/testcases/general/constants/circularity.dart:5:15: Error: Constant evaluation error:
+// const int a = b;
+//               ^
+// pkg/front_end/testcases/general/constants/circularity.dart:5:15: Context: Constant expression depends on itself.
+// const int a = b;
+//               ^
+// pkg/front_end/testcases/general/constants/circularity.dart:5:11: Context: While analyzing:
+// const int a = b;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/circularity.dart:7:15: Error: Constant evaluation error:
+// const int c = d;
+//               ^
+// pkg/front_end/testcases/general/constants/circularity.dart:8:17: Context: Constant expression depends on itself.
+// const int d = e + 1;
+//                 ^
+// pkg/front_end/testcases/general/constants/circularity.dart:7:11: Context: While analyzing:
+// const int c = d;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/circularity.dart:8:17: Error: Constant evaluation error:
+// const int d = e + 1;
+//                 ^
+// pkg/front_end/testcases/general/constants/circularity.dart:8:17: Context: Constant expression depends on itself.
+// const int d = e + 1;
+//                 ^
+// pkg/front_end/testcases/general/constants/circularity.dart:8:11: Context: While analyzing:
+// const int d = e + 1;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object /*hasConstConstructor*/  {
+  const constructor •({self::Class1* c = #C1}) → self::Class1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class2 extends core::Object /*hasConstConstructor*/  {
+  final field self::Class2* field;
+  const constructor •(core::int* value) → self::Class2*
+    : self::Class2::field = value =={core::num::==}{(core::Object*) →* core::bool*} 0 ?{self::Class2*} null : #C3, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class3 extends core::Object /*hasConstConstructor*/  {
+  const constructor •([self::Class3* c = #C4]) → self::Class3*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class4 extends core::Object /*hasConstConstructor*/  {
+  const constructor •({self::Class4* c = invalid-expression "Constant expression depends on itself."}) → self::Class4*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field core::int* a = invalid-expression "Constant expression depends on itself.";
+static const field core::int* b = invalid-expression "Constant expression depends on itself.";
+static const field core::int* c = invalid-expression "Constant expression depends on itself.";
+static const field core::int* d = invalid-expression "Constant expression depends on itself.";
+static const field core::int* e = invalid-expression "Constant expression depends on itself.";
+static const field self::Class1* c1_0 = #C1;
+static const field self::Class1* c1_1 = #C1;
+static const field self::Class1* c1_2 = #C1;
+static const field self::Class2* c2_0 = #C5;
+static const field self::Class2* c2_1 = #C3;
+static const field self::Class2* c2_2 = #C5;
+static const field self::Class3* c3_0 = #C4;
+static const field self::Class3* c3_1 = #C4;
+static const field self::Class3* c3_2 = #C4;
+static const field self::Class4* c4_0 = invalid-expression "Constant expression depends on itself.";
+static const field self::Class4* c4_1 = #C6;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Class1 {}
+  #C2 = null
+  #C3 = self::Class2 {field:#C2}
+  #C4 = self::Class3 {}
+  #C5 = self::Class2 {field:#C3}
+  #C6 = self::Class4 {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///circularity.dart:
+- Class1. (from org-dartlang-testcase:///circularity.dart:12:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Class2. (from org-dartlang-testcase:///circularity.dart:21:9)
+- Class3. (from org-dartlang-testcase:///circularity.dart:29:9)
+- Class4. (from org-dartlang-testcase:///circularity.dart:37:9)
diff --git a/pkg/front_end/testcases/general/constants/const_asserts.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/const_asserts.dart.weak.modular.expect
new file mode 100644
index 0000000..be365f6
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/const_asserts.dart.weak.modular.expect
@@ -0,0 +1,220 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/const_asserts.dart:17:51: Error: A value of type 'int' can't be assigned to a variable of type 'bool'.
+//   const Foo.withInvalidCondition(this.x) : assert(x);
+//                                                   ^
+//
+// pkg/front_end/testcases/general/constants/const_asserts.dart:19:21: Error: Constant expression expected.
+// Try inserting 'const'.
+//       : assert(bool.fromEnvironment("foo", defaultValue: null));
+//                     ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/constants/const_asserts.dart:32:24: Error: Constant evaluation error:
+// const Foo foo2 = const Foo(0);
+//                        ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:8:18: Context: This assertion failed with message: x is not positive
+//       : assert(x > 0, "x is not positive"),
+//                  ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:32:11: Context: While analyzing:
+// const Foo foo2 = const Foo(0);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/const_asserts.dart:33:24: Error: Constant evaluation error:
+// const Foo foo3 = const Foo.withMessage(42);
+//                        ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:15:18: Context: This assertion failed with message: btw foo was false
+//       : assert(x < 0, "btw foo was ${const bool.fromEnvironment("foo")}");
+//                  ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:33:11: Context: While analyzing:
+// const Foo foo3 = const Foo.withMessage(42);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/const_asserts.dart:34:24: Error: Constant evaluation error:
+// const Foo foo4 = const Foo.withInvalidMessage(42);
+//                        ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:16:56: Context: Expected constant '42' to be of type 'String', but was of type 'int'.
+//   const Foo.withInvalidMessage(this.x) : assert(x < 0, x);
+//                                                        ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:34:11: Context: While analyzing:
+// const Foo foo4 = const Foo.withInvalidMessage(42);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/const_asserts.dart:36:24: Error: Constant evaluation error:
+// const Foo foo6 = const Foo.withNullConditionFromEnv1(42);
+//                        ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:19:21: Context: Expected constant 'null' to be of type 'bool', but was of type 'Null'.
+//       : assert(bool.fromEnvironment("foo", defaultValue: null));
+//                     ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:36:11: Context: While analyzing:
+// const Foo foo6 = const Foo.withNullConditionFromEnv1(42);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/const_asserts.dart:37:24: Error: Constant evaluation error:
+// const Foo foo7 = const Foo.withNullConditionFromEnv2(42);
+//                        ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:21:22: Context: Expected constant 'null' to be of type 'bool', but was of type 'Null'.
+//       : assert(const bool.fromEnvironment("foo", defaultValue: null));
+//                      ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:37:11: Context: While analyzing:
+// const Foo foo7 = const Foo.withNullConditionFromEnv2(42);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/const_asserts.dart:38:24: Error: Constant evaluation error:
+// const Bar bar1 = const Bar.withMessage(1);
+//                        ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:26:44: Context: This assertion failed with message: x is not negative
+//   const Bar.withMessage(this.x) : assert(x < 0, "x is not negative");
+//                                            ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:38:11: Context: While analyzing:
+// const Bar bar1 = const Bar.withMessage(1);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/const_asserts.dart:39:24: Error: Constant evaluation error:
+// const Bar bar2 = const Bar.withMessage(0);
+//                        ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:26:44: Context: This assertion failed with message: x is not negative
+//   const Bar.withMessage(this.x) : assert(x < 0, "x is not negative");
+//                                            ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:39:11: Context: While analyzing:
+// const Bar bar2 = const Bar.withMessage(0);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/const_asserts.dart:40:24: Error: Constant evaluation error:
+// const Bar bar3 = const Bar.withoutMessage(1);
+//                        ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:27:47: Context: This assertion failed.
+//   const Bar.withoutMessage(this.x) : assert(x < 0);
+//                                               ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:40:11: Context: While analyzing:
+// const Bar bar3 = const Bar.withoutMessage(1);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/const_asserts.dart:41:24: Error: Constant evaluation error:
+// const Bar bar4 = const Bar.withoutMessage(0);
+//                        ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:27:47: Context: This assertion failed.
+//   const Bar.withoutMessage(this.x) : assert(x < 0);
+//                                               ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:41:11: Context: While analyzing:
+// const Bar bar4 = const Bar.withoutMessage(0);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/const_asserts.dart:42:24: Error: Constant evaluation error:
+// const Bar bar5 = const Bar.withEmptyMessage(1);
+//                        ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:28:49: Context: This assertion failed.
+//   const Bar.withEmptyMessage(this.x) : assert(x < 0);
+//                                                 ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:42:11: Context: While analyzing:
+// const Bar bar5 = const Bar.withEmptyMessage(1);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/const_asserts.dart:43:24: Error: Constant evaluation error:
+// const Bar bar6 = const Bar.withEmptyMessage(0);
+//                        ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:28:49: Context: This assertion failed.
+//   const Bar.withEmptyMessage(this.x) : assert(x < 0);
+//                                                 ^
+// pkg/front_end/testcases/general/constants/const_asserts.dart:43:11: Context: While analyzing:
+// const Bar bar6 = const Bar.withEmptyMessage(0);
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  final field core::int* x;
+  const constructor •(core::int* x) → self::Foo*
+    : self::Foo::x = x, assert(x.{core::num::>}(0){(core::num*) →* core::bool*}, "x is not positive"), assert(x.{core::num::>}(0){(core::num*) →* core::bool*}), assert(x.{core::num::>}(0){(core::num*) →* core::bool*}, ""), assert(#C1 =={core::Object::==}{(core::Object*) →* core::bool*} false, "foo was ${#C1}"), assert(#C1 =={core::Object::==}{(core::Object*) →* core::bool*} false), super core::Object::•()
+    ;
+  const constructor withMessage(core::int* x) → self::Foo*
+    : self::Foo::x = x, assert(x.{core::num::<}(0){(core::num*) →* core::bool*}, "btw foo was ${#C1}"), super core::Object::•()
+    ;
+  const constructor withInvalidMessage(core::int* x) → self::Foo*
+    : self::Foo::x = x, assert(x.{core::num::<}(0){(core::num*) →* core::bool*}, x), super core::Object::•()
+    ;
+  const constructor withInvalidCondition(core::int* x) → self::Foo*
+    : self::Foo::x = x, assert(invalid-expression "pkg/front_end/testcases/general/constants/const_asserts.dart:17:51: Error: A value of type 'int' can't be assigned to a variable of type 'bool'.
+  const Foo.withInvalidCondition(this.x) : assert(x);
+                                                  ^" in x as{TypeError} core::bool*), super core::Object::•()
+    ;
+  const constructor withNullConditionFromEnv1(core::int* x) → self::Foo*
+    : self::Foo::x = x, assert(#C2), super core::Object::•()
+    ;
+  const constructor withNullConditionFromEnv2(core::int* x) → self::Foo*
+    : self::Foo::x = x, assert(#C2), super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar extends core::Object /*hasConstConstructor*/  {
+  final field core::int* x;
+  const constructor withMessage(core::int* x) → self::Bar*
+    : self::Bar::x = x, assert(x.{core::num::<}(0){(core::num*) →* core::bool*}, "x is not negative"), super core::Object::•()
+    ;
+  const constructor withoutMessage(core::int* x) → self::Bar*
+    : self::Bar::x = x, assert(x.{core::num::<}(0){(core::num*) →* core::bool*}), super core::Object::•()
+    ;
+  const constructor withEmptyMessage(core::int* x) → self::Bar*
+    : self::Bar::x = x, assert(x.{core::num::<}(0){(core::num*) →* core::bool*}), super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field self::Foo* foo1 = #C4;
+static const field self::Foo* foo2 = invalid-expression "This assertion failed with message: x is not positive";
+static const field self::Foo* foo3 = invalid-expression "This assertion failed with message: btw foo was false";
+static const field self::Foo* foo4 = invalid-expression "Expected constant '42' to be of type 'String', but was of type 'int'.";
+static const field self::Foo* foo5 = invalid-expression "pkg/front_end/testcases/general/constants/const_asserts.dart:17:51: Error: A value of type 'int' can't be assigned to a variable of type 'bool'.
+  const Foo.withInvalidCondition(this.x) : assert(x);
+                                                  ^";
+static const field self::Foo* foo6 = invalid-expression "Expected constant 'null' to be of type 'bool', but was of type 'Null'.";
+static const field self::Foo* foo7 = invalid-expression "Expected constant 'null' to be of type 'bool', but was of type 'Null'.";
+static const field self::Bar* bar1 = invalid-expression "This assertion failed with message: x is not negative";
+static const field self::Bar* bar2 = invalid-expression "This assertion failed with message: x is not negative";
+static const field self::Bar* bar3 = invalid-expression "This assertion failed.";
+static const field self::Bar* bar4 = invalid-expression "This assertion failed.";
+static const field self::Bar* bar5 = invalid-expression "This assertion failed.";
+static const field self::Bar* bar6 = invalid-expression "This assertion failed.";
+static method main() → dynamic {
+  core::print(#C4);
+}
+
+constants  {
+  #C1 = false
+  #C2 = null
+  #C3 = 1
+  #C4 = self::Foo {x:#C3}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///const_asserts.dart:
+- Foo. (from org-dartlang-testcase:///const_asserts.dart:7:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Foo.withMessage (from org-dartlang-testcase:///const_asserts.dart:14:9)
+- Foo.withInvalidMessage (from org-dartlang-testcase:///const_asserts.dart:16:9)
+- Foo.withInvalidCondition (from org-dartlang-testcase:///const_asserts.dart:17:9)
+- Foo.withNullConditionFromEnv1 (from org-dartlang-testcase:///const_asserts.dart:18:9)
+- Foo.withNullConditionFromEnv2 (from org-dartlang-testcase:///const_asserts.dart:20:9)
+- Bar.withMessage (from org-dartlang-testcase:///const_asserts.dart:26:9)
+- Bar.withoutMessage (from org-dartlang-testcase:///const_asserts.dart:27:9)
+- Bar.withEmptyMessage (from org-dartlang-testcase:///const_asserts.dart:28:9)
diff --git a/pkg/front_end/testcases/general/constants/const_collections.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/const_collections.dart.weak.modular.expect
new file mode 100644
index 0000000..456d5c3
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/const_collections.dart.weak.modular.expect
@@ -0,0 +1,513 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:23:51: Error: Unexpected type 'int' of a spread.  Expected 'dynamic' or an Iterable.
+// const List<String> barWithIntSpread = [...foo, ...fortyTwo];
+//                                                   ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:25:51: Error: Unexpected type 'Map<String, String>' of a spread.  Expected 'dynamic' or an Iterable.
+//  - 'Map' is from 'dart:core'.
+// const List<String> barWithMapSpread = [...foo, ...quux];
+//                                                   ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:41:50: Error: Unexpected type 'int' of a map spread entry.  Expected 'dynamic' or a Map.
+// const Set<String> quxWithIntSpread = {...baz, ...fortyTwo};
+//                                                  ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:42:38: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+// const Set<String> quxWithMapSpread = {...baz, ...quux};
+//                                      ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:48:59: Error: A value of type 'CustomIterable' can't be assigned to a variable of type 'String'.
+//  - 'CustomIterable' is from 'pkg/front_end/testcases/general/constants/const_collections.dart'.
+// const Set<String> quxWithCustomIterableSpread3 = {...baz, customIterable};
+//                                                           ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:58:60: Error: Unexpected type 'int' of a map spread entry.  Expected 'dynamic' or a Map.
+// const Map<String, String> quuzWithIntSpread = {...quux, ...fortyTwo};
+//                                                            ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:59:47: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+// const Map<String, String> quuzWithSetSpread = {...quux, ...baz};
+//                                               ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:60:46: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+// const Map<String, String> mapWithSetSpread = {...baz};
+//                                              ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:22:40: Error: Constant evaluation error:
+// const List<String> barWithNullSpread = [...foo, ...nullList];
+//                                        ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:22:52: Context: Null value during constant evaluation.
+// const List<String> barWithNullSpread = [...foo, ...nullList];
+//                                                    ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:22:20: Context: While analyzing:
+// const List<String> barWithNullSpread = [...foo, ...nullList];
+//                    ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:24:46: Error: Constant evaluation error:
+// const List<String> barWithIntDynamicSpread = [...foo, ...fortyTwoAsDynamic];
+//                                              ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:24:58: Context: Expected constant '42' to be of type 'Iterable<dynamic>', but was of type 'int'.
+//  - 'Iterable' is from 'dart:core'.
+// const List<String> barWithIntDynamicSpread = [...foo, ...fortyTwoAsDynamic];
+//                                                          ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:24:20: Context: While analyzing:
+// const List<String> barWithIntDynamicSpread = [...foo, ...fortyTwoAsDynamic];
+//                    ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:26:51: Error: Constant evaluation error:
+// const List<String> barWithCustomIterableSpread1 = [
+//                                                   ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:28:12: Context: Only lists and sets can be used in spreads in constant lists and sets.
+//   ...const CustomIterable()
+//            ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:26:20: Context: While analyzing:
+// const List<String> barWithCustomIterableSpread1 = [
+//                    ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:30:51: Error: Constant evaluation error:
+// const List<String> barWithCustomIterableSpread2 = [...bar, ...CustomIterable()];
+//                                                   ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:30:63: Context: Only lists and sets can be used in spreads in constant lists and sets.
+// const List<String> barWithCustomIterableSpread2 = [...bar, ...CustomIterable()];
+//                                                               ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:30:20: Context: While analyzing:
+// const List<String> barWithCustomIterableSpread2 = [...bar, ...CustomIterable()];
+//                    ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:32:51: Error: Constant evaluation error:
+// const List<String> barWithCustomIterableSpread3 = [...bar, ...customIterable];
+//                                                   ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:32:63: Context: Only lists and sets can be used in spreads in constant lists and sets.
+// const List<String> barWithCustomIterableSpread3 = [...bar, ...customIterable];
+//                                                               ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:32:20: Context: While analyzing:
+// const List<String> barWithCustomIterableSpread3 = [...bar, ...customIterable];
+//                    ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:33:43: Error: Constant evaluation error:
+// const List<String> listConcat = ["Hello"] + ["World"];
+//                                           ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:33:43: Context: The method '+' can't be invoked on '<String>["Hello"]' in a constant expression.
+// const List<String> listConcat = ["Hello"] + ["World"];
+//                                           ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:33:20: Context: While analyzing:
+// const List<String> listConcat = ["Hello"] + ["World"];
+//                    ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:40:39: Error: Constant evaluation error:
+// const Set<String> quxWithNullSpread = {...baz, ...nullSet};
+//                                       ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:40:51: Context: Null value during constant evaluation.
+// const Set<String> quxWithNullSpread = {...baz, ...nullSet};
+//                                                   ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:40:19: Context: While analyzing:
+// const Set<String> quxWithNullSpread = {...baz, ...nullSet};
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:43:50: Error: Constant evaluation error:
+// const Set<String> quxWithCustomIterableSpread1 = {
+//                                                  ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:45:12: Context: Only lists and sets can be used in spreads in constant lists and sets.
+//   ...const CustomIterable()
+//            ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:43:19: Context: While analyzing:
+// const Set<String> quxWithCustomIterableSpread1 = {
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:47:50: Error: Constant evaluation error:
+// const Set<String> quxWithCustomIterableSpread2 = {...baz, ...CustomIterable()};
+//                                                  ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:47:62: Context: Only lists and sets can be used in spreads in constant lists and sets.
+// const Set<String> quxWithCustomIterableSpread2 = {...baz, ...CustomIterable()};
+//                                                              ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:47:19: Context: While analyzing:
+// const Set<String> quxWithCustomIterableSpread2 = {...baz, ...CustomIterable()};
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:49:48: Error: Constant evaluation error:
+// const Set<dynamic> setWithNonPrimitiveEquals = {const WithEquals(42)};
+//                                                ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:49:55: Context: The element 'WithEquals {i: 42}' does not have a primitive operator '=='.
+//  - 'WithEquals' is from 'pkg/front_end/testcases/general/constants/const_collections.dart'.
+// const Set<dynamic> setWithNonPrimitiveEquals = {const WithEquals(42)};
+//                                                       ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:49:20: Context: While analyzing:
+// const Set<dynamic> setWithNonPrimitiveEquals = {const WithEquals(42)};
+//                    ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:50:40: Error: Constant evaluation error:
+// const Set<dynamic> setWithDuplicates = {42, 42};
+//                                        ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:50:45: Context: The element '42' conflicts with another existing element in the set.
+// const Set<dynamic> setWithDuplicates = {42, 42};
+//                                             ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:50:20: Context: While analyzing:
+// const Set<dynamic> setWithDuplicates = {42, 42};
+//                    ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:57:27: Error: Constant evaluation error:
+// const Map<String, String> quuzWithNullSpread = {...quux, ...nullMap};
+//                           ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:57:61: Context: Null value during constant evaluation.
+// const Map<String, String> quuzWithNullSpread = {...quux, ...nullMap};
+//                                                             ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:57:27: Context: While analyzing:
+// const Map<String, String> quuzWithNullSpread = {...quux, ...nullMap};
+//                           ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:61:27: Error: Constant evaluation error:
+// const Map<String, String> mapWithCustomMap1 = {...const CustomMap()};
+//                           ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:61:57: Context: Only maps can be used in spreads in constant maps.
+// const Map<String, String> mapWithCustomMap1 = {...const CustomMap()};
+//                                                         ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:61:27: Context: While analyzing:
+// const Map<String, String> mapWithCustomMap1 = {...const CustomMap()};
+//                           ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:62:27: Error: Constant evaluation error:
+// const Map<String, String> mapWithCustomMap2 = {...CustomMap()};
+//                           ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:62:51: Context: Only maps can be used in spreads in constant maps.
+// const Map<String, String> mapWithCustomMap2 = {...CustomMap()};
+//                                                   ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:62:27: Context: While analyzing:
+// const Map<String, String> mapWithCustomMap2 = {...CustomMap()};
+//                           ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:64:27: Error: Constant evaluation error:
+// const Map<String, String> mapWithCustomMap3 = {...customMap};
+//                           ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:64:51: Context: Only maps can be used in spreads in constant maps.
+// const Map<String, String> mapWithCustomMap3 = {...customMap};
+//                                                   ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:64:27: Context: While analyzing:
+// const Map<String, String> mapWithCustomMap3 = {...customMap};
+//                           ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:65:56: Error: Constant evaluation error:
+// const Map<dynamic, int> mapWithNonPrimitiveEqualsKey = {
+//                                                        ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:66:9: Context: The key 'WithEquals {i: 42}' does not have a primitive operator '=='.
+//  - 'WithEquals' is from 'pkg/front_end/testcases/general/constants/const_collections.dart'.
+//   const WithEquals(42): 42
+//         ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:65:25: Context: While analyzing:
+// const Map<dynamic, int> mapWithNonPrimitiveEqualsKey = {
+//                         ^
+//
+// pkg/front_end/testcases/general/constants/const_collections.dart:68:41: Error: Constant evaluation error:
+// const Map<int, int> mapWithDuplicates = {42: 42, 42: 42};
+//                                         ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:68:50: Context: The key '42' conflicts with another existing key in the map.
+// const Map<int, int> mapWithDuplicates = {42: 42, 42: 42};
+//                                                  ^
+// pkg/front_end/testcases/general/constants/const_collections.dart:68:21: Context: While analyzing:
+// const Map<int, int> mapWithDuplicates = {42: 42, 42: 42};
+//                     ^
+//
+import self as self;
+import "dart:collection" as col;
+import "dart:core" as core;
+
+import "dart:collection";
+
+class ConstIterable extends col::IterableBase<core::int*> /*hasConstConstructor*/  {
+  const constructor •() → self::ConstIterable*
+    : super col::IterableBase::•()
+    ;
+  get iterator() → core::Iterator<core::int*>*
+    return <core::int*>[].{core::Iterable::iterator}{core::Iterator<core::int*>*};
+  abstract member-signature method cast<R extends core::Object* = dynamic>() → core::Iterable<self::ConstIterable::cast::R*>*; -> core::Iterable::cast
+  abstract member-signature method followedBy(covariant-by-class core::Iterable<core::int*>* other) → core::Iterable<core::int*>*; -> core::Iterable::followedBy
+  abstract member-signature method map<T extends core::Object* = dynamic>((core::int*) →* self::ConstIterable::map::T* toElement) → core::Iterable<self::ConstIterable::map::T*>*; -> core::Iterable::map
+  abstract member-signature method where((core::int*) →* core::bool* test) → core::Iterable<core::int*>*; -> core::Iterable::where
+  abstract member-signature method whereType<T extends core::Object* = dynamic>() → core::Iterable<self::ConstIterable::whereType::T*>*; -> core::Iterable::whereType
+  abstract member-signature method expand<T extends core::Object* = dynamic>((core::int*) →* core::Iterable<self::ConstIterable::expand::T*>* toElements) → core::Iterable<self::ConstIterable::expand::T*>*; -> core::Iterable::expand
+  abstract member-signature method contains(core::Object* element) → core::bool*; -> core::Iterable::contains
+  abstract member-signature method forEach((core::int*) →* void action) → void; -> core::Iterable::forEach
+  abstract member-signature method reduce(covariant-by-class (core::int*, core::int*) →* core::int* combine) → core::int*; -> core::Iterable::reduce
+  abstract member-signature method fold<T extends core::Object* = dynamic>(self::ConstIterable::fold::T* initialValue, (self::ConstIterable::fold::T*, core::int*) →* self::ConstIterable::fold::T* combine) → self::ConstIterable::fold::T*; -> core::Iterable::fold
+  abstract member-signature method every((core::int*) →* core::bool* test) → core::bool*; -> core::Iterable::every
+  abstract member-signature method join([core::String* separator = #C1]) → core::String*; -> core::Iterable::join
+  abstract member-signature method any((core::int*) →* core::bool* test) → core::bool*; -> core::Iterable::any
+  abstract member-signature method toList({core::bool* growable = #C2}) → core::List<core::int*>*; -> core::Iterable::toList
+  abstract member-signature method toSet() → core::Set<core::int*>*; -> core::Iterable::toSet
+  abstract member-signature get length() → core::int*; -> core::Iterable::length
+  abstract member-signature get isEmpty() → core::bool*; -> core::Iterable::isEmpty
+  abstract member-signature get isNotEmpty() → core::bool*; -> core::Iterable::isNotEmpty
+  abstract member-signature method take(core::int* count) → core::Iterable<core::int*>*; -> core::Iterable::take
+  abstract member-signature method takeWhile((core::int*) →* core::bool* test) → core::Iterable<core::int*>*; -> core::Iterable::takeWhile
+  abstract member-signature method skip(core::int* count) → core::Iterable<core::int*>*; -> core::Iterable::skip
+  abstract member-signature method skipWhile((core::int*) →* core::bool* test) → core::Iterable<core::int*>*; -> core::Iterable::skipWhile
+  abstract member-signature method firstWhere((core::int*) →* core::bool* test, {covariant-by-class () →* core::int* orElse = #C3}) → core::int*; -> core::Iterable::firstWhere
+  abstract member-signature method lastWhere((core::int*) →* core::bool* test, {covariant-by-class () →* core::int* orElse = #C3}) → core::int*; -> core::Iterable::lastWhere
+  abstract member-signature method singleWhere((core::int*) →* core::bool* test, {covariant-by-class () →* core::int* orElse = #C3}) → core::int*; -> core::Iterable::singleWhere
+  abstract member-signature method elementAt(core::int* index) → core::int*; -> core::Iterable::elementAt
+  abstract member-signature method toString() → core::String*; -> core::Iterable::toString
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class WithEquals extends core::Object /*hasConstConstructor*/  {
+  final field core::int* i;
+  const constructor •(core::int* i) → self::WithEquals*
+    : self::WithEquals::i = i, super core::Object::•()
+    ;
+  operator ==(core::Object* o) → core::bool* {
+    return o is self::WithEquals* && (o{self::WithEquals*} as self::WithEquals*).{self::WithEquals::i}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} this.{self::WithEquals::i}{core::int*};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class CustomIterable extends col::IterableBase<core::String*> /*hasConstConstructor*/  {
+  const constructor •() → self::CustomIterable*
+    : super col::IterableBase::•()
+    ;
+  get iterator() → core::Iterator<core::String*>*
+    return <core::String*>[].{core::Iterable::iterator}{core::Iterator<core::String*>*};
+  abstract member-signature method cast<R extends core::Object* = dynamic>() → core::Iterable<self::CustomIterable::cast::R*>*; -> core::Iterable::cast
+  abstract member-signature method followedBy(covariant-by-class core::Iterable<core::String*>* other) → core::Iterable<core::String*>*; -> core::Iterable::followedBy
+  abstract member-signature method map<T extends core::Object* = dynamic>((core::String*) →* self::CustomIterable::map::T* toElement) → core::Iterable<self::CustomIterable::map::T*>*; -> core::Iterable::map
+  abstract member-signature method where((core::String*) →* core::bool* test) → core::Iterable<core::String*>*; -> core::Iterable::where
+  abstract member-signature method whereType<T extends core::Object* = dynamic>() → core::Iterable<self::CustomIterable::whereType::T*>*; -> core::Iterable::whereType
+  abstract member-signature method expand<T extends core::Object* = dynamic>((core::String*) →* core::Iterable<self::CustomIterable::expand::T*>* toElements) → core::Iterable<self::CustomIterable::expand::T*>*; -> core::Iterable::expand
+  abstract member-signature method contains(core::Object* element) → core::bool*; -> core::Iterable::contains
+  abstract member-signature method forEach((core::String*) →* void action) → void; -> core::Iterable::forEach
+  abstract member-signature method reduce(covariant-by-class (core::String*, core::String*) →* core::String* combine) → core::String*; -> core::Iterable::reduce
+  abstract member-signature method fold<T extends core::Object* = dynamic>(self::CustomIterable::fold::T* initialValue, (self::CustomIterable::fold::T*, core::String*) →* self::CustomIterable::fold::T* combine) → self::CustomIterable::fold::T*; -> core::Iterable::fold
+  abstract member-signature method every((core::String*) →* core::bool* test) → core::bool*; -> core::Iterable::every
+  abstract member-signature method join([core::String* separator = #C1]) → core::String*; -> core::Iterable::join
+  abstract member-signature method any((core::String*) →* core::bool* test) → core::bool*; -> core::Iterable::any
+  abstract member-signature method toList({core::bool* growable = #C2}) → core::List<core::String*>*; -> core::Iterable::toList
+  abstract member-signature method toSet() → core::Set<core::String*>*; -> core::Iterable::toSet
+  abstract member-signature get length() → core::int*; -> core::Iterable::length
+  abstract member-signature get isEmpty() → core::bool*; -> core::Iterable::isEmpty
+  abstract member-signature get isNotEmpty() → core::bool*; -> core::Iterable::isNotEmpty
+  abstract member-signature method take(core::int* count) → core::Iterable<core::String*>*; -> core::Iterable::take
+  abstract member-signature method takeWhile((core::String*) →* core::bool* test) → core::Iterable<core::String*>*; -> core::Iterable::takeWhile
+  abstract member-signature method skip(core::int* count) → core::Iterable<core::String*>*; -> core::Iterable::skip
+  abstract member-signature method skipWhile((core::String*) →* core::bool* test) → core::Iterable<core::String*>*; -> core::Iterable::skipWhile
+  abstract member-signature method firstWhere((core::String*) →* core::bool* test, {covariant-by-class () →* core::String* orElse = #C3}) → core::String*; -> core::Iterable::firstWhere
+  abstract member-signature method lastWhere((core::String*) →* core::bool* test, {covariant-by-class () →* core::String* orElse = #C3}) → core::String*; -> core::Iterable::lastWhere
+  abstract member-signature method singleWhere((core::String*) →* core::bool* test, {covariant-by-class () →* core::String* orElse = #C3}) → core::String*; -> core::Iterable::singleWhere
+  abstract member-signature method elementAt(core::int* index) → core::String*; -> core::Iterable::elementAt
+  abstract member-signature method toString() → core::String*; -> core::Iterable::toString
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class CustomMap extends core::Object implements core::Map<core::String*, core::String*> /*hasConstConstructor*/  {
+  const constructor •() → self::CustomMap*
+    : super core::Object::•()
+    ;
+  @#C4
+  get entries() → core::Iterable<core::MapEntry<core::String*, core::String*>*>*
+    return <core::MapEntry<core::String*, core::String*>*>[];
+  @#C4
+  operator [](core::Object* key) → core::String*
+    return throw new core::UnimplementedError::•();
+  @#C4
+  operator []=(covariant-by-class core::String* key, covariant-by-class core::String* value) → void
+    return throw new core::UnimplementedError::•();
+  @#C4
+  method cast<RK extends core::Object* = dynamic, RV extends core::Object* = dynamic>() → core::Map<self::CustomMap::cast::RK*, self::CustomMap::cast::RV*>*
+    return throw new core::UnimplementedError::•();
+  @#C4
+  method clear() → void
+    return throw new core::UnimplementedError::•();
+  @#C4
+  method containsKey(core::Object* key) → core::bool*
+    return throw new core::UnimplementedError::•();
+  @#C4
+  method containsValue(core::Object* value) → core::bool*
+    return throw new core::UnimplementedError::•();
+  @#C4
+  get isEmpty() → core::bool*
+    return throw new core::UnimplementedError::•();
+  @#C4
+  get isNotEmpty() → core::bool*
+    return throw new core::UnimplementedError::•();
+  @#C4
+  get keys() → core::Iterable<core::String*>*
+    return throw new core::UnimplementedError::•();
+  @#C4
+  get length() → core::int*
+    return throw new core::UnimplementedError::•();
+  @#C4
+  method remove(core::Object* key) → core::String*
+    return throw new core::UnimplementedError::•();
+  @#C4
+  get values() → core::Iterable<core::String*>*
+    return throw new core::UnimplementedError::•();
+  @#C4
+  method addAll(covariant-by-class core::Map<core::String*, core::String*>* other) → void
+    return throw new core::UnimplementedError::•();
+  @#C4
+  method addEntries(covariant-by-class core::Iterable<core::MapEntry<core::String*, core::String*>*>* newEntries) → void
+    return throw new core::UnimplementedError::•();
+  @#C4
+  method forEach((core::String*, core::String*) →* void f) → void
+    return throw new core::UnimplementedError::•();
+  @#C4
+  method putIfAbsent(covariant-by-class core::String* key, covariant-by-class () →* core::String* ifAbsent) → core::String*
+    return throw new core::UnimplementedError::•();
+  @#C4
+  method updateAll(covariant-by-class (core::String*, core::String*) →* core::String* update) → void
+    return throw new core::UnimplementedError::•();
+  @#C4
+  method removeWhere((core::String*, core::String*) →* core::bool* predicate) → void
+    return throw new core::UnimplementedError::•();
+  method update(covariant-by-class core::String* key, covariant-by-class (core::String*) →* core::String* update, {covariant-by-class () →* core::String* ifAbsent = #C3}) → core::String*
+    return throw new core::UnimplementedError::•();
+  method map<K2 extends core::Object* = dynamic, V2 extends core::Object* = dynamic>((core::String*, core::String*) →* core::MapEntry<self::CustomMap::map::K2*, self::CustomMap::map::V2*>* f) → core::Map<self::CustomMap::map::K2*, self::CustomMap::map::V2*>*
+    return throw new core::UnimplementedError::•();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field core::int* fortyTwo = #C5;
+static const field dynamic fortyTwoAsDynamic = #C5;
+static const field core::List<core::String*>* nullList = #C3;
+static const field core::List<core::String*>* foo = #C8;
+static const field core::List<core::String*>* bar = #C10;
+static field core::List<core::String*>* barAsVar = block {
+  final core::List<core::String*>* #t1 = core::List::of<core::String*>(#C8);
+  #t1.{core::List::add}{Invariant}("!"){(core::String*) →* void};
+} =>#t1;
+static const field core::List<core::String*>* barWithNullSpread = invalid-expression "Null value during constant evaluation.";
+static const field core::List<core::String*>* barWithIntSpread = invalid-expression "pkg/front_end/testcases/general/constants/const_collections.dart:23:51: Error: Unexpected type 'int' of a spread.  Expected 'dynamic' or an Iterable.
+const List<String> barWithIntSpread = [...foo, ...fortyTwo];
+                                                  ^";
+static const field core::List<core::String*>* barWithIntDynamicSpread = invalid-expression "Expected constant '42' to be of type 'Iterable<dynamic>', but was of type 'int'.
+ - 'Iterable' is from 'dart:core'.";
+static const field core::List<core::String*>* barWithMapSpread = invalid-expression "pkg/front_end/testcases/general/constants/const_collections.dart:25:51: Error: Unexpected type 'Map<String, String>' of a spread.  Expected 'dynamic' or an Iterable.
+ - 'Map' is from 'dart:core'.
+const List<String> barWithMapSpread = [...foo, ...quux];
+                                                  ^";
+static const field core::List<core::String*>* barWithCustomIterableSpread1 = invalid-expression "Only lists and sets can be used in spreads in constant lists and sets.";
+static const field core::List<core::String*>* barWithCustomIterableSpread2 = invalid-expression "Only lists and sets can be used in spreads in constant lists and sets.";
+static const field self::CustomIterable* customIterable = #C11;
+static const field core::List<core::String*>* barWithCustomIterableSpread3 = invalid-expression "Only lists and sets can be used in spreads in constant lists and sets.";
+static const field core::List<core::String*>* listConcat = invalid-expression "The method '+' can't be invoked on '<String>[\"Hello\"]' in a constant expression.";
+static const field core::Set<core::String*>* nullSet = #C3;
+static const field core::Set<core::String*>* baz = #C12;
+static const field core::Set<core::String*>* qux = #C13;
+static const field core::Set<core::String*>* quxWithNullSpread = invalid-expression "Null value during constant evaluation.";
+static const field core::Set<core::String*>* quxWithIntSpread = invalid-expression "pkg/front_end/testcases/general/constants/const_collections.dart:41:50: Error: Unexpected type 'int' of a map spread entry.  Expected 'dynamic' or a Map.
+const Set<String> quxWithIntSpread = {...baz, ...fortyTwo};
+                                                 ^";
+static const field core::Set<core::String*>* quxWithMapSpread = invalid-expression "pkg/front_end/testcases/general/constants/const_collections.dart:42:38: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+const Set<String> quxWithMapSpread = {...baz, ...quux};
+                                     ^";
+static const field core::Set<core::String*>* quxWithCustomIterableSpread1 = invalid-expression "Only lists and sets can be used in spreads in constant lists and sets.";
+static const field core::Set<core::String*>* quxWithCustomIterableSpread2 = invalid-expression "Only lists and sets can be used in spreads in constant lists and sets.";
+static const field core::Set<core::String*>* quxWithCustomIterableSpread3 = invalid-expression "pkg/front_end/testcases/general/constants/const_collections.dart:48:59: Error: A value of type 'CustomIterable' can't be assigned to a variable of type 'String'.
+ - 'CustomIterable' is from 'pkg/front_end/testcases/general/constants/const_collections.dart'.
+const Set<String> quxWithCustomIterableSpread3 = {...baz, customIterable};
+                                                          ^";
+static const field core::Set<dynamic>* setWithNonPrimitiveEquals = invalid-expression "The element 'WithEquals {i: 42}' does not have a primitive operator '=='.
+ - 'WithEquals' is from 'pkg/front_end/testcases/general/constants/const_collections.dart'.";
+static const field core::Set<dynamic>* setWithDuplicates = invalid-expression "The element '42' conflicts with another existing element in the set.";
+static const field core::Map<core::String*, core::String*>* nullMap = #C3;
+static const field core::Map<core::String*, core::String*>* quux = #C14;
+static const field core::Map<core::String*, core::String*>* quuz = #C16;
+static const field core::Map<core::String*, core::String*>* quuzWithNullSpread = invalid-expression "Null value during constant evaluation.";
+static const field core::Map<core::String*, core::String*>* quuzWithIntSpread = invalid-expression "pkg/front_end/testcases/general/constants/const_collections.dart:58:60: Error: Unexpected type 'int' of a map spread entry.  Expected 'dynamic' or a Map.
+const Map<String, String> quuzWithIntSpread = {...quux, ...fortyTwo};
+                                                           ^";
+static const field core::Map<core::String*, core::String*>* quuzWithSetSpread = invalid-expression "pkg/front_end/testcases/general/constants/const_collections.dart:59:47: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+const Map<String, String> quuzWithSetSpread = {...quux, ...baz};
+                                              ^";
+static const field core::Map<core::String*, core::String*>* mapWithSetSpread = invalid-expression "pkg/front_end/testcases/general/constants/const_collections.dart:60:46: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+const Map<String, String> mapWithSetSpread = {...baz};
+                                             ^";
+static const field core::Map<core::String*, core::String*>* mapWithCustomMap1 = invalid-expression "Only maps can be used in spreads in constant maps.";
+static const field core::Map<core::String*, core::String*>* mapWithCustomMap2 = invalid-expression "Only maps can be used in spreads in constant maps.";
+static const field core::Map<core::String*, core::String*>* customMap = #C17;
+static const field core::Map<core::String*, core::String*>* mapWithCustomMap3 = invalid-expression "Only maps can be used in spreads in constant maps.";
+static const field core::Map<dynamic, core::int*>* mapWithNonPrimitiveEqualsKey = invalid-expression "The key 'WithEquals {i: 42}' does not have a primitive operator '=='.
+ - 'WithEquals' is from 'pkg/front_end/testcases/general/constants/const_collections.dart'.";
+static const field core::Map<core::int*, core::int*>* mapWithDuplicates = invalid-expression "The key '42' conflicts with another existing key in the map.";
+static get fooAsGetter() → core::List<core::String*>*
+  return #C8;
+static get barAsGetter() → core::List<core::String*>*
+  return #C10;
+static get bazAsGetter() → core::Set<core::String*>*
+  return #C12;
+static get quxAsGetter() → core::Set<core::String*>*
+  return #C13;
+static get quuxAsGetter() → core::Map<core::String*, core::String*>*
+  return #C14;
+static get quuzAsGetter() → core::Map<core::String*, core::String*>*
+  return #C16;
+static method main() → dynamic {
+  core::print(#C10);
+  core::print(#C13);
+  core::print(#C16);
+  core::print( block {
+    final core::Set<core::String*>* #t2 = col::LinkedHashSet::•<core::String*>();
+    #t2.{core::Set::add}{Invariant}("hello"){(core::String*) →* core::bool*};
+  } =>#t2);
+  core::print(#C18);
+}
+
+constants  {
+  #C1 = ""
+  #C2 = true
+  #C3 = null
+  #C4 = core::_Override {}
+  #C5 = 42
+  #C6 = "hello"
+  #C7 = "world"
+  #C8 = <core::String*>[#C6, #C7]
+  #C9 = "!"
+  #C10 = <core::String*>[#C6, #C7, #C9]
+  #C11 = self::CustomIterable {}
+  #C12 = <core::String*>{#C6, #C7}
+  #C13 = <core::String*>{#C6, #C7, #C9}
+  #C14 = <core::String*, core::String*>{#C6:#C7)
+  #C15 = "bye!"
+  #C16 = <core::String*, core::String*>{#C6:#C7, #C9:#C15)
+  #C17 = self::CustomMap {}
+  #C18 = <core::String*>{#C6}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///const_collections.dart:
+- CustomIterable. (from org-dartlang-testcase:///const_collections.dart:79:9)
+- IterableBase. (from org-dartlang-sdk:///sdk/lib/collection/iterable.dart:219:9)
+- Iterable. (from org-dartlang-sdk:///sdk/lib/core/iterable.dart:87:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- WithEquals. (from org-dartlang-testcase:///const_collections.dart:72:9)
+- CustomMap. (from org-dartlang-testcase:///const_collections.dart:84:9)
diff --git a/pkg/front_end/testcases/general/constants/const_constructor_coverage.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/const_constructor_coverage.dart.weak.modular.expect
new file mode 100644
index 0000000..75eedd4
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/const_constructor_coverage.dart.weak.modular.expect
@@ -0,0 +1,155 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "const_constructor_coverage_lib1.dart" as con;
+
+import "org-dartlang-testcase:///const_constructor_coverage_lib1.dart";
+import "org-dartlang-testcase:///const_constructor_coverage_lib2.dart";
+
+static const field con::Foo* foo1 = #C4;
+static const field con::Foo* foo2 = #C4;
+static const field con::Foo* foo3 = #C4;
+static const field con::Foo* foo4 = #C4;
+static method main() → dynamic {
+  core::print(#C4);
+}
+
+library;
+import self as con;
+import "dart:core" as core;
+import "const_constructor_coverage_lib2.dart" as con2;
+
+import "org-dartlang-testcase:///const_constructor_coverage_lib2.dart";
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  final field con::Bar* bar;
+  const constructor •() → con::Foo*
+    : con::Foo::bar = #C3, super core::Object::•()
+    ;
+  const constructor named1() → con::Foo*
+    : con::Foo::bar = #C3, super core::Object::•()
+    ;
+  const constructor named2() → con::Foo*
+    : con::Foo::bar = #C3, super core::Object::•()
+    ;
+  const constructor named3() → con::Foo*
+    : con::Foo::bar = #C3, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar extends core::Object /*hasConstConstructor*/  {
+  final field con2::Baz* baz;
+  const constructor •() → con::Bar*
+    : con::Bar::baz = #C2, super core::Object::•()
+    ;
+  const constructor named1() → con::Bar*
+    : con::Bar::baz = #C2, super core::Object::•()
+    ;
+  const constructor named2() → con::Bar*
+    : con::Bar::baz = #C2, super core::Object::•()
+    ;
+  const constructor named3() → con::Bar*
+    : con::Bar::baz = #C2, super core::Object::•()
+    ;
+  const constructor named4(core::int* i) → con::Bar*
+    : con::Bar::baz = i.{core::num::>}(0){(core::num*) →* core::bool*} ?{con2::Baz*} #C2 : #C2, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field con::Foo* foo = #C4;
+
+library;
+import self as con2;
+import "dart:core" as core;
+import "const_constructor_coverage_lib1.dart" as con;
+
+import "org-dartlang-testcase:///const_constructor_coverage_lib1.dart";
+
+class Baz extends core::Object /*hasConstConstructor*/  {
+  final field con::Bar* bar;
+  const constructor •() → con2::Baz*
+    : con2::Baz::bar = null, super core::Object::•()
+    ;
+  const constructor named1() → con2::Baz*
+    : con2::Baz::bar = null, super core::Object::•()
+    ;
+  const constructor named2() → con2::Baz*
+    : con2::Baz::bar = null, super core::Object::•()
+    ;
+  const constructor named3() → con2::Baz*
+    : con2::Baz::bar = #C3, super core::Object::•()
+    ;
+  const constructor named4() → con2::Baz*
+    : con2::Baz::bar = null, super core::Object::•()
+    ;
+  const constructor named5() → con2::Baz*
+    : con2::Baz::bar = null, super core::Object::•()
+    ;
+  const constructor named6() → con2::Baz*
+    : con2::Baz::bar = null, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field con2::Baz* baz = #C2;
+static const field con::Foo* foo = #C4;
+static const field con::Bar* bar = #C3;
+
+constants  {
+  #C1 = null
+  #C2 = con2::Baz {bar:#C1}
+  #C3 = con::Bar {baz:#C2}
+  #C4 = con::Foo {bar:#C3}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///const_constructor_coverage.dart:
+- Foo. (from org-dartlang-testcase:///const_constructor_coverage_lib1.dart:9:15)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Foo.named1 (from org-dartlang-testcase:///const_constructor_coverage_lib1.dart:10:15)
+- Foo.named2 (from org-dartlang-testcase:///const_constructor_coverage_lib1.dart:11:15)
+- Foo.named3 (from org-dartlang-testcase:///const_constructor_coverage_lib1.dart:12:15)
+
+org-dartlang-testcase:///const_constructor_coverage_lib1.dart:
+- Bar. (from org-dartlang-testcase:///const_constructor_coverage_lib1.dart:17:15)
+- Baz. (from org-dartlang-testcase:///const_constructor_coverage_lib2.dart:9:15)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Bar.named1 (from org-dartlang-testcase:///const_constructor_coverage_lib1.dart:18:15)
+- Baz.named1 (from org-dartlang-testcase:///const_constructor_coverage_lib2.dart:10:15)
+- Baz.named5 (from org-dartlang-testcase:///const_constructor_coverage_lib2.dart:14:15)
+- Baz.named6 (from org-dartlang-testcase:///const_constructor_coverage_lib2.dart:15:15)
+- Foo.named3 (from org-dartlang-testcase:///const_constructor_coverage_lib1.dart:12:15)
+
+org-dartlang-testcase:///const_constructor_coverage_lib2.dart:
+- Bar.named3 (from org-dartlang-testcase:///const_constructor_coverage_lib1.dart:20:15)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Baz.named4 (from org-dartlang-testcase:///const_constructor_coverage_lib2.dart:13:15)
+- Foo.named2 (from org-dartlang-testcase:///const_constructor_coverage_lib1.dart:11:15)
+- Bar.named2 (from org-dartlang-testcase:///const_constructor_coverage_lib1.dart:19:15)
diff --git a/pkg/front_end/testcases/general/constants/from_lib/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/from_lib/main.dart.weak.modular.expect
new file mode 100644
index 0000000..4af39e7
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/from_lib/main.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///main_lib.dart" as a;
+
+static const field core::Map<core::int*, core::String*>* map = #C3;
+static const field core::Set<core::int*>* set = #C6;
+static const field core::List<core::int*>* list = #C7;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 1
+  #C2 = "a"
+  #C3 = <core::int*, core::String*>{#C1:#C2)
+  #C4 = 2
+  #C5 = 3
+  #C6 = <core::int*>{#C4, #C5}
+  #C7 = <core::int*>[#C5, #C4]
+}
diff --git a/pkg/front_end/testcases/general/constants/function_invocation.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/function_invocation.dart.weak.modular.expect
new file mode 100644
index 0000000..ade1d05
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/function_invocation.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/function_invocation.dart:7:20: Error: Method invocation is not a constant expression.
+// const invocation = tearOff();
+//                    ^^^^^^^
+//
+import self as self;
+
+static const field () → dynamic tearOff = #C1;
+static const field invalid-type invocation = invalid-expression "pkg/front_end/testcases/general/constants/function_invocation.dart:7:20: Error: Method invocation is not a constant expression.
+const invocation = tearOff();
+                   ^^^^^^^";
+static method method() → dynamic {}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::method
+}
diff --git a/pkg/front_end/testcases/general/constants/issue46925.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/issue46925.dart.weak.modular.expect
new file mode 100644
index 0000000..86587cd
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/issue46925.dart.weak.modular.expect
@@ -0,0 +1,95 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/issue46925.dart:14:21: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   const v1 = MyClass<String>.new;
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/issue46925.dart:14:30: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   const v1 = MyClass<String>.new;
+//                              ^^^
+//
+// pkg/front_end/testcases/general/constants/issue46925.dart:14:30: Error: Member not found: 'new'.
+//   const v1 = MyClass<String>.new;
+//                              ^^^
+//
+// pkg/front_end/testcases/general/constants/issue46925.dart:15:21: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   const v2 = MyClass<int>.constr;
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/issue46925.dart:15:27: Error: Member not found: 'constr'.
+//   const v2 = MyClass<int>.constr;
+//                           ^^^^^^
+//
+// pkg/front_end/testcases/general/constants/issue46925.dart:16:21: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   const v3 = MyClass<int>.new;
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/issue46925.dart:16:27: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   const v3 = MyClass<int>.new;
+//                           ^^^
+//
+// pkg/front_end/testcases/general/constants/issue46925.dart:16:27: Error: Member not found: 'new'.
+//   const v3 = MyClass<int>.new;
+//                           ^^^
+//
+// pkg/front_end/testcases/general/constants/issue46925.dart:17:21: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   const v4 = MyClass<String>.constr;
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/issue46925.dart:17:30: Error: Member not found: 'constr'.
+//   const v4 = MyClass<String>.constr;
+//                              ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class MyClass<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field dynamic a;
+  const constructor •(core::int i, core::int j) → self::MyClass<self::MyClass::T%>
+    : self::MyClass::a = i.{core::num::+}(j){(core::num) → core::int}, super core::Object::•()
+    ;
+  const constructor constr() → self::MyClass<self::MyClass::T%>
+    : self::MyClass::a = 0, super core::Object::•()
+    ;
+}
+static method test() → dynamic {
+  const invalid-type v1 = invalid-expression "pkg/front_end/testcases/general/constants/issue46925.dart:14:30: Error: Member not found: 'new'.
+  const v1 = MyClass<String>.new;
+                             ^^^";
+  const invalid-type v2 = invalid-expression "pkg/front_end/testcases/general/constants/issue46925.dart:15:27: Error: Member not found: 'constr'.
+  const v2 = MyClass<int>.constr;
+                          ^^^^^^";
+  const invalid-type v3 = invalid-expression "pkg/front_end/testcases/general/constants/issue46925.dart:16:27: Error: Member not found: 'new'.
+  const v3 = MyClass<int>.new;
+                          ^^^";
+  const invalid-type v4 = invalid-expression "pkg/front_end/testcases/general/constants/issue46925.dart:17:30: Error: Member not found: 'constr'.
+  const v4 = MyClass<String>.constr;
+                             ^^^^^^";
+  const dynamic c1 = invalid-expression "pkg/front_end/testcases/general/constants/issue46925.dart:14:30: Error: Member not found: 'new'.
+  const v1 = MyClass<String>.new;
+                             ^^^";
+  const dynamic c2 = invalid-expression "pkg/front_end/testcases/general/constants/issue46925.dart:14:30: Error: Member not found: 'new'.
+  const v1 = MyClass<String>.new;
+                             ^^^";
+  const dynamic c3 = invalid-expression "pkg/front_end/testcases/general/constants/issue46925.dart:15:27: Error: Member not found: 'constr'.
+  const v2 = MyClass<int>.constr;
+                          ^^^^^^";
+  const dynamic c4 = invalid-expression "pkg/front_end/testcases/general/constants/issue46925.dart:15:27: Error: Member not found: 'constr'.
+  const v2 = MyClass<int>.constr;
+                          ^^^^^^";
+  const dynamic c5 = invalid-expression "pkg/front_end/testcases/general/constants/issue46925.dart:16:27: Error: Member not found: 'new'.
+  const v3 = MyClass<int>.new;
+                          ^^^";
+  const dynamic c6 = invalid-expression "pkg/front_end/testcases/general/constants/issue46925.dart:17:30: Error: Member not found: 'constr'.
+  const v4 = MyClass<String>.constr;
+                             ^^^^^^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/constants/issue_43431.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/issue_43431.dart.weak.modular.expect
new file mode 100644
index 0000000..65e909f
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/issue_43431.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/issue_43431.dart:9:3: Error: Only static fields can be declared as const.
+// Try using 'final' instead of 'const', or adding the keyword 'static'.
+//   const x = Foo();
+//   ^^^^^
+//
+// pkg/front_end/testcases/general/constants/issue_43431.dart:9:13: Error: Constant expression expected.
+// Try inserting 'const'.
+//   const x = Foo();
+//             ^^^
+//
+// pkg/front_end/testcases/general/constants/issue_43431.dart:8:9: Error: Constructor is marked 'const' so all fields must be final.
+//   const Foo({bool x: true});
+//         ^
+// pkg/front_end/testcases/general/constants/issue_43431.dart:9:9: Context: Field isn't final, but constructor is 'const'.
+//   const x = Foo();
+//         ^
+//
+// pkg/front_end/testcases/general/constants/issue_43431.dart:9:13: Error: Constant evaluation error:
+//   const x = Foo();
+//             ^
+// pkg/front_end/testcases/general/constants/issue_43431.dart:9:13: Context: Constant expression depends on itself.
+//   const x = Foo();
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  field self::Foo* x = invalid-expression "Constant expression depends on itself.";
+  const constructor •({core::bool* x = #C1}) → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = true
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue_43431.dart:
+- Foo. (from org-dartlang-testcase:///issue_43431.dart:8:9)
diff --git a/pkg/front_end/testcases/general/constants/js_semantics/issue45376.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/js_semantics/issue45376.dart.weak.modular.expect
new file mode 100644
index 0000000..966e5dd
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/js_semantics/issue45376.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class MyClass extends core::Object /*hasConstConstructor*/  {
+  final field core::int a;
+  final field core::int b;
+  const constructor •(dynamic i1, dynamic i2) → self::MyClass
+    : self::MyClass::a = i1{dynamic}.>>>(i2) as{TypeError,ForDynamic,ForNonNullableByDefault} core::int, self::MyClass::b = i1{dynamic}.>>>(i2) as{TypeError,ForDynamic,ForNonNullableByDefault} core::int, super core::Object::•()
+    ;
+  static method _#new#tearOff(dynamic i1, dynamic i2) → self::MyClass
+    return new self::MyClass::•(i1, i2);
+}
+static method test() → dynamic {}
+static method main() → dynamic {}
+
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue45376.dart:
+- MyClass. (from org-dartlang-testcase:///issue45376.dart:8:9)
+- Object. (from org-dartlang-sdk:///lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/constants/js_semantics/issue46123.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/js_semantics/issue46123.dart.weak.modular.expect
new file mode 100644
index 0000000..c62f518
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/js_semantics/issue46123.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/js_semantics/issue46123.dart:13:17: Error: Constant evaluation error:
+// test() => const ParallaxOptions();
+//                 ^
+// pkg/front_end/testcases/general/constants/js_semantics/issue46123.dart:13:17: Context: External factory constructors can't be evaluated in constant expressions.
+// test() => const ParallaxOptions();
+//                 ^
+//
+import self as self;
+import "package:js/js.dart" as js;
+import "dart:core" as core;
+
+import "package:js/js.dart";
+
+@#C2
+@#C3
+class ParallaxOptions extends core::Object {
+  external static factory •() → self::ParallaxOptions;
+  static method _#new#tearOff() → self::ParallaxOptions
+    return self::ParallaxOptions::•();
+}
+static method test() → dynamic
+  return invalid-expression "External factory constructors can't be evaluated in constant expressions.";
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = js::JS {name:#C1}
+  #C3 = js::_Anonymous {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue46123.dart:
+- JS. (from org-dartlang-testcase-sdk:///pkg/js/lib/js.dart:21:9)
+- Object. (from org-dartlang-sdk:///lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/constants/js_semantics/issue46123b.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/js_semantics/issue46123b.dart.weak.modular.expect
new file mode 100644
index 0000000..215e011
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/js_semantics/issue46123b.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/js_semantics/issue46123b.dart:13:17: Error: Constant evaluation error:
+// test() => const ParallaxOptions();
+//                 ^
+// pkg/front_end/testcases/general/constants/js_semantics/issue46123b.dart:13:17: Context: External constructors can't be evaluated in constant expressions.
+// test() => const ParallaxOptions();
+//                 ^
+//
+import self as self;
+import "package:js/js.dart" as js;
+import "dart:core" as core;
+
+import "package:js/js.dart";
+
+@#C2
+@#C3
+class ParallaxOptions extends core::Object /*hasConstConstructor*/  {
+  external const constructor •() → self::ParallaxOptions
+    : super core::Object::•()
+    ;
+  static method _#new#tearOff() → self::ParallaxOptions
+    return new self::ParallaxOptions::•();
+}
+static method test() → dynamic
+  return invalid-expression "External constructors can't be evaluated in constant expressions.";
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = js::JS {name:#C1}
+  #C3 = js::_Anonymous {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue46123b.dart:
+- JS. (from org-dartlang-testcase-sdk:///pkg/js/lib/js.dart:21:9)
+- Object. (from org-dartlang-sdk:///lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart.weak.modular.expect
new file mode 100644
index 0000000..e2269a8
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart.weak.modular.expect
@@ -0,0 +1,148 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:13:23: Error: '+' is not a prefix operator.
+// Try removing '+'.
+// const int unaryPlus = +2;
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:9:23: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+// const int divZero = 2 / 0;
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:5:30: Error: Constant evaluation error:
+// const int shiftNegative1 = 2 << -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:5:30: Context: Binary operator '<<' on '2.0' requires non-negative operand, but was '-1.0'.
+// const int shiftNegative1 = 2 << -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:5:11: Context: While analyzing:
+// const int shiftNegative1 = 2 << -1;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:6:30: Error: Constant evaluation error:
+// const int shiftNegative2 = 2 >>> -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:6:30: Context: Binary operator '>>>' on '2.0' requires non-negative operand, but was '-1.0'.
+// const int shiftNegative2 = 2 >>> -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:6:11: Context: While analyzing:
+// const int shiftNegative2 = 2 >>> -1;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:7:30: Error: Constant evaluation error:
+// const int shiftNegative3 = 2 >> -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:7:30: Context: Binary operator '>>' on '2.0' requires non-negative operand, but was '-1.0'.
+// const int shiftNegative3 = 2 >> -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:7:11: Context: While analyzing:
+// const int shiftNegative3 = 2 >> -1;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:8:23: Error: Constant evaluation error:
+// const int modZero = 2 % 0;
+//                       ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:8:23: Context: Binary operator '%' on '2.0' requires non-zero divisor, but divisor was '0'.
+// const int modZero = 2 % 0;
+//                       ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:8:11: Context: While analyzing:
+// const int modZero = 2 % 0;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:10:26: Error: Constant evaluation error:
+// const int intdivZero = 2 ~/ 0;
+//                          ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:10:26: Context: Binary operator '~/' on '2.0' requires non-zero divisor, but divisor was '0'.
+// const int intdivZero = 2 ~/ 0;
+//                          ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:10:11: Context: While analyzing:
+// const int intdivZero = 2 ~/ 0;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:37:40: Error: Constant evaluation error:
+// const int doubleTruncateDivZero = 84.2 ~/ 0;
+//                                        ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:37:40: Context: Binary operator '~/' on '84.2' requires non-zero divisor, but divisor was '0'.
+// const int doubleTruncateDivZero = 84.2 ~/ 0;
+//                                        ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:37:11: Context: While analyzing:
+// const int doubleTruncateDivZero = 84.2 ~/ 0;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:39:40: Error: Constant evaluation error:
+// const int doubleTruncateDivNull = 84.2 ~/ nil;
+//                                        ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:39:40: Context: Binary operator '~/' on '84.2' requires operand of type 'num', but was of type 'Null'.
+// const int doubleTruncateDivNull = 84.2 ~/ nil;
+//                                        ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:39:11: Context: While analyzing:
+// const int doubleTruncateDivNull = 84.2 ~/ nil;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:41:39: Error: Constant evaluation error:
+// const int doubleTruncateDivNaN = 84.2 ~/ doubleNan;
+//                                       ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:41:39: Context: Binary operator '84.2 ~/ NaN' results is Infinity or NaN.
+// const int doubleTruncateDivNaN = 84.2 ~/ doubleNan;
+//                                       ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:41:11: Context: While analyzing:
+// const int doubleTruncateDivNaN = 84.2 ~/ doubleNan;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+static const field core::int shiftNegative1 = invalid-expression "Binary operator '<<' on '2.0' requires non-negative operand, but was '-1.0'.";
+static const field core::int shiftNegative2 = invalid-expression "Binary operator '>>>' on '2.0' requires non-negative operand, but was '-1.0'.";
+static const field core::int shiftNegative3 = invalid-expression "Binary operator '>>' on '2.0' requires non-negative operand, but was '-1.0'.";
+static const field core::int modZero = invalid-expression "Binary operator '%' on '2.0' requires non-zero divisor, but divisor was '0'.";
+static const field core::int divZero = invalid-expression "pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:9:23: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+const int divZero = 2 / 0;
+                      ^";
+static const field core::int intdivZero = invalid-expression "Binary operator '~/' on '2.0' requires non-zero divisor, but divisor was '0'.";
+static const field core::int unaryMinus = #C1;
+static const field core::int unaryTilde = #C2;
+static const field core::int unaryPlus = invalid-expression "pkg/front_end/testcases/general/constants/js_semantics/number_folds.dart:13:23: Error: This couldn't be parsed.
+const int unaryPlus = +2;
+                      ^";
+static const field core::int binaryPlus = #C3;
+static const field core::int binaryMinus = #C3;
+static const field core::int binaryTimes = #C3;
+static const field core::double binaryDiv = #C3;
+static const field core::int binaryTildeDiv = #C3;
+static const field core::int binaryMod = #C3;
+static const field core::int binaryOr = #C3;
+static const field core::int binaryAnd = #C3;
+static const field core::int binaryXor = #C3;
+static const field core::int binaryShift1 = #C3;
+static const field core::int binaryShift2 = #C3;
+static const field core::int binaryShift3 = #C4;
+static const field core::int binaryShift4 = #C3;
+static const field core::int binaryShift5 = #C5;
+static const field core::bool binaryLess = #C6;
+static const field core::bool binaryLessEqual = #C7;
+static const field core::bool binaryGreaterEqual = #C7;
+static const field core::bool binaryGreater = #C6;
+static const field core::int doubleTruncateDiv = #C3;
+static const field core::int doubleTruncateDivZero = invalid-expression "Binary operator '~/' on '84.2' requires non-zero divisor, but divisor was '0'.";
+static const field dynamic nil = #C8;
+static const field core::int doubleTruncateDivNull = invalid-expression "Binary operator '~/' on '84.2' requires operand of type 'num', but was of type 'Null'.";
+static const field core::double doubleNan = #C9;
+static const field core::int doubleTruncateDivNaN = invalid-expression "Binary operator '84.2 ~/ NaN' results is Infinity or NaN.";
+static const field core::int bigNumber = #C10;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = -2.0
+  #C2 = 4294967293.0
+  #C3 = 42.0
+  #C4 = 0.0
+  #C5 = 4294967295.0
+  #C6 = false
+  #C7 = true
+  #C8 = null
+  #C9 = NaN
+  #C10 = 9223372036854776000.0
+}
diff --git a/pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..220b700
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart.weak.modular.expect
@@ -0,0 +1,132 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:14:23: Error: '+' is not a prefix operator.
+// Try removing '+'.
+// const int unaryPlus = +2;
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:10:23: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+// const int divZero = 2 / 0;
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:7:30: Error: Constant evaluation error:
+// const int shiftNegative1 = 2 << -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:7:30: Context: Binary operator '<<' on '2.0' requires non-negative operand, but was '-1.0'.
+// const int shiftNegative1 = 2 << -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:7:11: Context: While analyzing:
+// const int shiftNegative1 = 2 << -1;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:8:30: Error: Constant evaluation error:
+// const int shiftNegative3 = 2 >> -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:8:30: Context: Binary operator '>>' on '2.0' requires non-negative operand, but was '-1.0'.
+// const int shiftNegative3 = 2 >> -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:8:11: Context: While analyzing:
+// const int shiftNegative3 = 2 >> -1;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:9:23: Error: Constant evaluation error:
+// const int modZero = 2 % 0;
+//                       ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:9:23: Context: Binary operator '%' on '2.0' requires non-zero divisor, but divisor was '0'.
+// const int modZero = 2 % 0;
+//                       ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:9:11: Context: While analyzing:
+// const int modZero = 2 % 0;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:11:26: Error: Constant evaluation error:
+// const int intdivZero = 2 ~/ 0;
+//                          ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:11:26: Context: Binary operator '~/' on '2.0' requires non-zero divisor, but divisor was '0'.
+// const int intdivZero = 2 ~/ 0;
+//                          ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:11:11: Context: While analyzing:
+// const int intdivZero = 2 ~/ 0;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:35:40: Error: Constant evaluation error:
+// const int doubleTruncateDivZero = 84.2 ~/ 0;
+//                                        ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:35:40: Context: Binary operator '~/' on '84.2' requires non-zero divisor, but divisor was '0'.
+// const int doubleTruncateDivZero = 84.2 ~/ 0;
+//                                        ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:35:11: Context: While analyzing:
+// const int doubleTruncateDivZero = 84.2 ~/ 0;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:36:40: Error: Constant evaluation error:
+// const int doubleTruncateDivNull = 84.2 ~/ null;
+//                                        ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:36:40: Context: Binary operator '~/' on '84.2' requires operand of type 'num', but was of type 'Null'.
+// const int doubleTruncateDivNull = 84.2 ~/ null;
+//                                        ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:36:11: Context: While analyzing:
+// const int doubleTruncateDivNull = 84.2 ~/ null;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:38:39: Error: Constant evaluation error:
+// const int doubleTruncateDivNaN = 84.2 ~/ doubleNan;
+//                                       ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:38:39: Context: Binary operator '84.2 ~/ NaN' results is Infinity or NaN.
+// const int doubleTruncateDivNaN = 84.2 ~/ doubleNan;
+//                                       ^
+// pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:38:11: Context: While analyzing:
+// const int doubleTruncateDivNaN = 84.2 ~/ doubleNan;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+static const field core::int* shiftNegative1 = invalid-expression "Binary operator '<<' on '2.0' requires non-negative operand, but was '-1.0'.";
+static const field core::int* shiftNegative3 = invalid-expression "Binary operator '>>' on '2.0' requires non-negative operand, but was '-1.0'.";
+static const field core::int* modZero = invalid-expression "Binary operator '%' on '2.0' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* divZero = invalid-expression "pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:10:23: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+const int divZero = 2 / 0;
+                      ^";
+static const field core::int* intdivZero = invalid-expression "Binary operator '~/' on '2.0' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* unaryMinus = #C1;
+static const field core::int* unaryTilde = #C2;
+static const field core::int* unaryPlus = invalid-expression "pkg/front_end/testcases/general/constants/js_semantics/number_folds_opt_out.dart:14:23: Error: This couldn't be parsed.
+const int unaryPlus = +2;
+                      ^";
+static const field core::int* binaryPlus = #C3;
+static const field core::int* binaryMinus = #C3;
+static const field core::int* binaryTimes = #C3;
+static const field core::double* binaryDiv = #C3;
+static const field core::int* binaryTildeDiv = #C3;
+static const field core::int* binaryMod = #C3;
+static const field core::int* binaryOr = #C3;
+static const field core::int* binaryAnd = #C3;
+static const field core::int* binaryXor = #C3;
+static const field core::int* binaryShift1 = #C3;
+static const field core::int* binaryShift4 = #C3;
+static const field core::int* binaryShift5 = #C4;
+static const field core::bool* binaryLess = #C5;
+static const field core::bool* binaryLessEqual = #C6;
+static const field core::bool* binaryGreaterEqual = #C6;
+static const field core::bool* binaryGreater = #C5;
+static const field core::int* doubleTruncateDiv = #C3;
+static const field core::int* doubleTruncateDivZero = invalid-expression "Binary operator '~/' on '84.2' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* doubleTruncateDivNull = invalid-expression "Binary operator '~/' on '84.2' requires operand of type 'num', but was of type 'Null'.";
+static const field core::double* doubleNan = #C7;
+static const field core::int* doubleTruncateDivNaN = invalid-expression "Binary operator '84.2 ~/ NaN' results is Infinity or NaN.";
+static const field core::int* bigNumber = #C8;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = -2.0
+  #C2 = 4294967293.0
+  #C3 = 42.0
+  #C4 = 4294967295.0
+  #C5 = false
+  #C6 = true
+  #C7 = NaN
+  #C8 = 9223372036854776000.0
+}
diff --git a/pkg/front_end/testcases/general/constants/js_semantics/on_double.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/js_semantics/on_double.dart.weak.modular.expect
new file mode 100644
index 0000000..03c80f1
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/js_semantics/on_double.dart.weak.modular.expect
@@ -0,0 +1,151 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:27:26: Error: Constant evaluation error:
+//   const Class c2 = Class.doubleShift(b, 1);
+//                          ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:21:45: Context: Binary operator '>>' on '1.5' requires operand of type 'int', but was of type 'double'.
+//   const Class.doubleShift(i1, i2) : a = (i1 >> i2);
+//                                             ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:27:15: Context: While analyzing:
+//   const Class c2 = Class.doubleShift(b, 1);
+//               ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:29:26: Error: Constant evaluation error:
+//   const Class c4 = Class.tripleShift(b, 1);
+//                          ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:22:45: Context: Binary operator '>>>' on '1.5' requires operand of type 'int', but was of type 'double'.
+//   const Class.tripleShift(i1, i2) : a = (i1 >>> i2);
+//                                             ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:29:15: Context: While analyzing:
+//   const Class c4 = Class.tripleShift(b, 1);
+//               ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:32:26: Error: Constant evaluation error:
+//   const Class d2 = Class.doubleShift(1, b);
+//                          ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:21:45: Context: Binary operator '>>' on '1.5' requires operand of type 'int', but was of type 'double'.
+//   const Class.doubleShift(i1, i2) : a = (i1 >> i2);
+//                                             ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:32:15: Context: While analyzing:
+//   const Class d2 = Class.doubleShift(1, b);
+//               ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:34:26: Error: Constant evaluation error:
+//   const Class d4 = Class.tripleShift(1, b);
+//                          ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:22:45: Context: Binary operator '>>>' on '1.5' requires operand of type 'int', but was of type 'double'.
+//   const Class.tripleShift(i1, i2) : a = (i1 >>> i2);
+//                                             ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:34:15: Context: While analyzing:
+//   const Class d4 = Class.tripleShift(1, b);
+//               ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:37:26: Error: Constant evaluation error:
+//   const Class e2 = Class.doubleShift(1.5, 1);
+//                          ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:21:45: Context: Binary operator '>>' on '1.5' requires operand of type 'int', but was of type 'double'.
+//   const Class.doubleShift(i1, i2) : a = (i1 >> i2);
+//                                             ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:37:15: Context: While analyzing:
+//   const Class e2 = Class.doubleShift(1.5, 1);
+//               ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:39:26: Error: Constant evaluation error:
+//   const Class e4 = Class.tripleShift(1.5, 1);
+//                          ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:22:45: Context: Binary operator '>>>' on '1.5' requires operand of type 'int', but was of type 'double'.
+//   const Class.tripleShift(i1, i2) : a = (i1 >>> i2);
+//                                             ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:39:15: Context: While analyzing:
+//   const Class e4 = Class.tripleShift(1.5, 1);
+//               ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:9:22: Error: Constant evaluation error:
+// const dynamic c1 = b >> 1;
+//                      ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:9:22: Context: Binary operator '>>' on '1.5' requires operand of type 'int', but was of type 'double'.
+// const dynamic c1 = b >> 1;
+//                      ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:9:15: Context: While analyzing:
+// const dynamic c1 = b >> 1;
+//               ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:11:22: Error: Constant evaluation error:
+// const dynamic c3 = b >>> 1;
+//                      ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:11:22: Context: Binary operator '>>>' on '1.5' requires operand of type 'int', but was of type 'double'.
+// const dynamic c3 = b >>> 1;
+//                      ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:11:15: Context: While analyzing:
+// const dynamic c3 = b >>> 1;
+//               ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:14:22: Error: Constant evaluation error:
+// const dynamic d1 = 1 >> b;
+//                      ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:14:25: Context: Expected constant '1.5' to be of type 'int', but was of type 'double'.
+// const dynamic d1 = 1 >> b;
+//                         ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:14:15: Context: While analyzing:
+// const dynamic d1 = 1 >> b;
+//               ^
+//
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:16:22: Error: Constant evaluation error:
+// const dynamic d3 = 1 >>> b;
+//                      ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:16:26: Context: Expected constant '1.5' to be of type 'int', but was of type 'double'.
+// const dynamic d3 = 1 >>> b;
+//                          ^
+// pkg/front_end/testcases/general/constants/js_semantics/on_double.dart:16:15: Context: While analyzing:
+// const dynamic d3 = 1 >>> b;
+//               ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object /*hasConstConstructor*/  {
+  final field core::int a;
+  const constructor doubleShift(dynamic i1, dynamic i2) → self::Class
+    : self::Class::a = i1{dynamic}.>>(i2) as{TypeError,ForDynamic,ForNonNullableByDefault} core::int, super core::Object::•()
+    ;
+  const constructor tripleShift(dynamic i1, dynamic i2) → self::Class
+    : self::Class::a = i1{dynamic}.>>>(i2) as{TypeError,ForDynamic,ForNonNullableByDefault} core::int, super core::Object::•()
+    ;
+  static method _#doubleShift#tearOff(dynamic i1, dynamic i2) → self::Class
+    return new self::Class::doubleShift(i1, i2);
+  static method _#tripleShift#tearOff(dynamic i1, dynamic i2) → self::Class
+    return new self::Class::tripleShift(i1, i2);
+}
+static const field dynamic a = #C1;
+static const field dynamic b = #C2;
+static const field dynamic c0 = #C3;
+static const field dynamic c1 = invalid-expression "Binary operator '>>' on '1.5' requires operand of type 'int', but was of type 'double'.";
+static const field dynamic c2 = #C3;
+static const field dynamic c3 = invalid-expression "Binary operator '>>>' on '1.5' requires operand of type 'int', but was of type 'double'.";
+static const field dynamic d0 = #C3;
+static const field dynamic d1 = invalid-expression "Expected constant '1.5' to be of type 'int', but was of type 'double'.";
+static const field dynamic d2 = #C3;
+static const field dynamic d3 = invalid-expression "Expected constant '1.5' to be of type 'int', but was of type 'double'.";
+static method main() → dynamic {
+  const self::Class c2 = invalid-expression "Binary operator '>>' on '1.5' requires operand of type 'int', but was of type 'double'.";
+  const self::Class c4 = invalid-expression "Binary operator '>>>' on '1.5' requires operand of type 'int', but was of type 'double'.";
+  const self::Class d2 = invalid-expression "Binary operator '>>' on '1.5' requires operand of type 'int', but was of type 'double'.";
+  const self::Class d4 = invalid-expression "Binary operator '>>>' on '1.5' requires operand of type 'int', but was of type 'double'.";
+  const self::Class e2 = invalid-expression "Binary operator '>>' on '1.5' requires operand of type 'int', but was of type 'double'.";
+  const self::Class e4 = invalid-expression "Binary operator '>>>' on '1.5' requires operand of type 'int', but was of type 'double'.";
+}
+
+constants  {
+  #C1 = 1.0
+  #C2 = 1.5
+  #C3 = 0.0
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///on_double.dart:
+- Class.doubleShift (from org-dartlang-testcase:///on_double.dart:21:9)
+- Object. (from org-dartlang-sdk:///lib/core/object.dart:25:9)
+- Class.tripleShift (from org-dartlang-testcase:///on_double.dart:22:9)
diff --git a/pkg/front_end/testcases/general/constants/js_semantics/various.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/js_semantics/various.dart.weak.modular.expect
new file mode 100644
index 0000000..0570489
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/js_semantics/various.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static const field core::bool* y = #C1;
+static const field core::bool* z = #C2;
+static const field core::Object* maybeInt = #C3;
+static const field core::bool* isItInt = #C2;
+static const field core::bool* isItDouble = #C2;
+static const field core::int* actualInt = #C3;
+static const field core::bool* isItInt2 = #C2;
+static const field core::bool* isItDouble2 = #C2;
+static const field core::Object* maybeDouble = #C3;
+static const field core::bool* isItInt3 = #C2;
+static const field core::bool* isItDouble3 = #C2;
+static const field core::double* actualDouble = #C3;
+static const field core::bool* isItInt4 = #C2;
+static const field core::bool* isItDouble4 = #C2;
+static const field core::Object* maybeDouble2 = #C4;
+static const field core::bool* isItInt5 = #C1;
+static const field core::bool* isItDouble5 = #C2;
+static const field core::double* actualDouble2 = #C4;
+static const field core::bool* isItInt6 = #C1;
+static const field core::bool* isItDouble7 = #C2;
+static const field core::bool* zeroPointZeroIdentical = #C2;
+static const field core::bool* zeroPointZeroIdenticalToZero = #C2;
+static const field core::bool* zeroIdenticalToZeroPointZero = #C2;
+static const field core::bool* nanIdentical = #C1;
+static const field core::bool* stringIdentical = #C2;
+static const field core::bool* string2Identical = #C1;
+static const field core::bool* zeroPointZeroEqual = #C2;
+static const field core::bool* zeroPointZeroEqualToZero = #C2;
+static const field core::bool* zeroEqualToZeroPointZero = #C2;
+static const field core::bool* nanEqual = #C1;
+static const field core::bool* stringEqual = #C2;
+static const field core::bool* string2Equal = #C1;
+static const field core::int* intFortyTwo = #C3;
+static const field core::String* intStringConcat = #C5;
+
+constants  {
+  #C1 = false
+  #C2 = true
+  #C3 = 42.0
+  #C4 = 42.42
+  #C5 = "hello1764"
+}
diff --git a/pkg/front_end/testcases/general/constants/no_experiments/various.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/no_experiments/various.dart.weak.modular.expect
new file mode 100644
index 0000000..376dfb4
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/no_experiments/various.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+static const field core::Symbol* tripleShiftSymbol = #C1;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #>>>
+}
diff --git a/pkg/front_end/testcases/general/constants/non_const_constructor.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/non_const_constructor.dart.weak.modular.expect
new file mode 100644
index 0000000..378710d4
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/non_const_constructor.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/non_const_constructor.dart:8:3: Error: A const constructor can't have a body.
+// Try removing either the 'const' keyword or the body.
+//   const Class.named() {
+//   ^^^^^
+//
+// pkg/front_end/testcases/general/constants/non_const_constructor.dart:13:17: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+// Try using a constructor or factory that is 'const'.
+// const a = const Class();
+//                 ^^^^^
+//
+// pkg/front_end/testcases/general/constants/non_const_constructor.dart:14:17: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+// Try using a constructor or factory that is 'const'.
+// const b = const Class.named();
+//                 ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  constructor named() → self::Class
+    : super core::Object::•() {
+    1;
+  }
+}
+static const field invalid-type a = invalid-expression "pkg/front_end/testcases/general/constants/non_const_constructor.dart:13:17: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+Try using a constructor or factory that is 'const'.
+const a = const Class();
+                ^^^^^";
+static const field invalid-type b = invalid-expression "pkg/front_end/testcases/general/constants/non_const_constructor.dart:14:17: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+Try using a constructor or factory that is 'const'.
+const b = const Class.named();
+                ^^^^^";
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/constants/non_const_variable.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/non_const_variable.dart.weak.modular.expect
new file mode 100644
index 0000000..a600694
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/non_const_variable.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/non_const_variable.dart:7:13: Error: Not a constant expression.
+//   const b = a;
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method method() → dynamic {
+  core::int a = 0;
+  const invalid-type b = invalid-expression "pkg/front_end/testcases/general/constants/non_const_variable.dart:7:13: Error: Not a constant expression.
+  const b = a;
+            ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/constants/number_folds.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/number_folds.dart.weak.modular.expect
new file mode 100644
index 0000000..6de8923
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/number_folds.dart.weak.modular.expect
@@ -0,0 +1,145 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/number_folds.dart:13:23: Error: '+' is not a prefix operator.
+// Try removing '+'.
+// const int unaryPlus = +2;
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/number_folds.dart:9:23: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+// const int divZero = 2 / 0;
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/number_folds.dart:5:30: Error: Constant evaluation error:
+// const int shiftNegative1 = 2 << -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:5:30: Context: Binary operator '<<' on '2' requires non-negative operand, but was '-1'.
+// const int shiftNegative1 = 2 << -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:5:11: Context: While analyzing:
+// const int shiftNegative1 = 2 << -1;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/number_folds.dart:6:30: Error: Constant evaluation error:
+// const int shiftNegative2 = 2 >>> -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:6:30: Context: Binary operator '>>>' on '2' requires non-negative operand, but was '-1'.
+// const int shiftNegative2 = 2 >>> -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:6:11: Context: While analyzing:
+// const int shiftNegative2 = 2 >>> -1;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/number_folds.dart:7:30: Error: Constant evaluation error:
+// const int shiftNegative3 = 2 >> -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:7:30: Context: Binary operator '>>' on '2' requires non-negative operand, but was '-1'.
+// const int shiftNegative3 = 2 >> -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:7:11: Context: While analyzing:
+// const int shiftNegative3 = 2 >> -1;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/number_folds.dart:8:23: Error: Constant evaluation error:
+// const int modZero = 2 % 0;
+//                       ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:8:23: Context: Binary operator '%' on '2' requires non-zero divisor, but divisor was '0'.
+// const int modZero = 2 % 0;
+//                       ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:8:11: Context: While analyzing:
+// const int modZero = 2 % 0;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/number_folds.dart:10:26: Error: Constant evaluation error:
+// const int intdivZero = 2 ~/ 0;
+//                          ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:10:26: Context: Binary operator '~/' on '2' requires non-zero divisor, but divisor was '0'.
+// const int intdivZero = 2 ~/ 0;
+//                          ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:10:11: Context: While analyzing:
+// const int intdivZero = 2 ~/ 0;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/number_folds.dart:36:40: Error: Constant evaluation error:
+// const int doubleTruncateDivZero = 84.2 ~/ 0;
+//                                        ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:36:40: Context: Binary operator '~/' on '84.2' requires non-zero divisor, but divisor was '0'.
+// const int doubleTruncateDivZero = 84.2 ~/ 0;
+//                                        ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:36:11: Context: While analyzing:
+// const int doubleTruncateDivZero = 84.2 ~/ 0;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/number_folds.dart:38:40: Error: Constant evaluation error:
+// const int doubleTruncateDivNull = 84.2 ~/ nil;
+//                                        ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:38:40: Context: Binary operator '~/' on '84.2' requires operand of type 'num', but was of type 'Null'.
+// const int doubleTruncateDivNull = 84.2 ~/ nil;
+//                                        ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:38:11: Context: While analyzing:
+// const int doubleTruncateDivNull = 84.2 ~/ nil;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/number_folds.dart:40:39: Error: Constant evaluation error:
+// const int doubleTruncateDivNaN = 84.2 ~/ doubleNan;
+//                                       ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:40:39: Context: Binary operator '84.2 ~/ NaN' results is Infinity or NaN.
+// const int doubleTruncateDivNaN = 84.2 ~/ doubleNan;
+//                                       ^
+// pkg/front_end/testcases/general/constants/number_folds.dart:40:11: Context: While analyzing:
+// const int doubleTruncateDivNaN = 84.2 ~/ doubleNan;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+static const field core::int shiftNegative1 = invalid-expression "Binary operator '<<' on '2' requires non-negative operand, but was '-1'.";
+static const field core::int shiftNegative2 = invalid-expression "Binary operator '>>>' on '2' requires non-negative operand, but was '-1'.";
+static const field core::int shiftNegative3 = invalid-expression "Binary operator '>>' on '2' requires non-negative operand, but was '-1'.";
+static const field core::int modZero = invalid-expression "Binary operator '%' on '2' requires non-zero divisor, but divisor was '0'.";
+static const field core::int divZero = invalid-expression "pkg/front_end/testcases/general/constants/number_folds.dart:9:23: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+const int divZero = 2 / 0;
+                      ^";
+static const field core::int intdivZero = invalid-expression "Binary operator '~/' on '2' requires non-zero divisor, but divisor was '0'.";
+static const field core::int unaryMinus = #C1;
+static const field core::int unaryTilde = #C2;
+static const field core::int unaryPlus = invalid-expression "pkg/front_end/testcases/general/constants/number_folds.dart:13:23: Error: This couldn't be parsed.
+const int unaryPlus = +2;
+                      ^";
+static const field core::int binaryPlus = #C3;
+static const field core::int binaryMinus = #C3;
+static const field core::int binaryTimes = #C3;
+static const field core::double binaryDiv = #C4;
+static const field core::int binaryTildeDiv = #C3;
+static const field core::int binaryMod = #C3;
+static const field core::int binaryOr = #C3;
+static const field core::int binaryAnd = #C3;
+static const field core::int binaryXor = #C3;
+static const field core::int binaryShift1 = #C3;
+static const field core::int binaryShift2 = #C3;
+static const field core::int binaryShift3 = #C5;
+static const field core::int binaryShift4 = #C3;
+static const field core::bool binaryLess = #C6;
+static const field core::bool binaryLessEqual = #C7;
+static const field core::bool binaryGreaterEqual = #C7;
+static const field core::bool binaryGreater = #C6;
+static const field core::int doubleTruncateDiv = #C3;
+static const field core::int doubleTruncateDivZero = invalid-expression "Binary operator '~/' on '84.2' requires non-zero divisor, but divisor was '0'.";
+static const field dynamic nil = #C8;
+static const field core::int doubleTruncateDivNull = invalid-expression "Binary operator '~/' on '84.2' requires operand of type 'num', but was of type 'Null'.";
+static const field core::double doubleNan = #C9;
+static const field core::int doubleTruncateDivNaN = invalid-expression "Binary operator '84.2 ~/ NaN' results is Infinity or NaN.";
+static method main() → dynamic {}
+
+constants  {
+  #C1 = -2
+  #C2 = -3
+  #C3 = 42
+  #C4 = 42.0
+  #C5 = 0
+  #C6 = false
+  #C7 = true
+  #C8 = null
+  #C9 = NaN
+}
diff --git a/pkg/front_end/testcases/general/constants/number_folds_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/number_folds_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..44bc90e
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/number_folds_opt_out.dart.weak.modular.expect
@@ -0,0 +1,129 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:14:23: Error: '+' is not a prefix operator.
+// Try removing '+'.
+// const int unaryPlus = +2;
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:10:23: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+// const int divZero = 2 / 0;
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:7:30: Error: Constant evaluation error:
+// const int shiftNegative1 = 2 << -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:7:30: Context: Binary operator '<<' on '2' requires non-negative operand, but was '-1'.
+// const int shiftNegative1 = 2 << -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:7:11: Context: While analyzing:
+// const int shiftNegative1 = 2 << -1;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:8:30: Error: Constant evaluation error:
+// const int shiftNegative3 = 2 >> -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:8:30: Context: Binary operator '>>' on '2' requires non-negative operand, but was '-1'.
+// const int shiftNegative3 = 2 >> -1;
+//                              ^
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:8:11: Context: While analyzing:
+// const int shiftNegative3 = 2 >> -1;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:9:23: Error: Constant evaluation error:
+// const int modZero = 2 % 0;
+//                       ^
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:9:23: Context: Binary operator '%' on '2' requires non-zero divisor, but divisor was '0'.
+// const int modZero = 2 % 0;
+//                       ^
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:9:11: Context: While analyzing:
+// const int modZero = 2 % 0;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:11:26: Error: Constant evaluation error:
+// const int intdivZero = 2 ~/ 0;
+//                          ^
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:11:26: Context: Binary operator '~/' on '2' requires non-zero divisor, but divisor was '0'.
+// const int intdivZero = 2 ~/ 0;
+//                          ^
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:11:11: Context: While analyzing:
+// const int intdivZero = 2 ~/ 0;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:34:40: Error: Constant evaluation error:
+// const int doubleTruncateDivZero = 84.2 ~/ 0;
+//                                        ^
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:34:40: Context: Binary operator '~/' on '84.2' requires non-zero divisor, but divisor was '0'.
+// const int doubleTruncateDivZero = 84.2 ~/ 0;
+//                                        ^
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:34:11: Context: While analyzing:
+// const int doubleTruncateDivZero = 84.2 ~/ 0;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:35:40: Error: Constant evaluation error:
+// const int doubleTruncateDivNull = 84.2 ~/ null;
+//                                        ^
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:35:40: Context: Binary operator '~/' on '84.2' requires operand of type 'num', but was of type 'Null'.
+// const int doubleTruncateDivNull = 84.2 ~/ null;
+//                                        ^
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:35:11: Context: While analyzing:
+// const int doubleTruncateDivNull = 84.2 ~/ null;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:37:39: Error: Constant evaluation error:
+// const int doubleTruncateDivNaN = 84.2 ~/ doubleNan;
+//                                       ^
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:37:39: Context: Binary operator '84.2 ~/ NaN' results is Infinity or NaN.
+// const int doubleTruncateDivNaN = 84.2 ~/ doubleNan;
+//                                       ^
+// pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:37:11: Context: While analyzing:
+// const int doubleTruncateDivNaN = 84.2 ~/ doubleNan;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+static const field core::int* shiftNegative1 = invalid-expression "Binary operator '<<' on '2' requires non-negative operand, but was '-1'.";
+static const field core::int* shiftNegative3 = invalid-expression "Binary operator '>>' on '2' requires non-negative operand, but was '-1'.";
+static const field core::int* modZero = invalid-expression "Binary operator '%' on '2' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* divZero = invalid-expression "pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:10:23: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+const int divZero = 2 / 0;
+                      ^";
+static const field core::int* intdivZero = invalid-expression "Binary operator '~/' on '2' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* unaryMinus = #C1;
+static const field core::int* unaryTilde = #C2;
+static const field core::int* unaryPlus = invalid-expression "pkg/front_end/testcases/general/constants/number_folds_opt_out.dart:14:23: Error: This couldn't be parsed.
+const int unaryPlus = +2;
+                      ^";
+static const field core::int* binaryPlus = #C3;
+static const field core::int* binaryMinus = #C3;
+static const field core::int* binaryTimes = #C3;
+static const field core::double* binaryDiv = #C4;
+static const field core::int* binaryTildeDiv = #C3;
+static const field core::int* binaryMod = #C3;
+static const field core::int* binaryOr = #C3;
+static const field core::int* binaryAnd = #C3;
+static const field core::int* binaryXor = #C3;
+static const field core::int* binaryShift1 = #C3;
+static const field core::int* binaryShift4 = #C3;
+static const field core::bool* binaryLess = #C5;
+static const field core::bool* binaryLessEqual = #C6;
+static const field core::bool* binaryGreaterEqual = #C6;
+static const field core::bool* binaryGreater = #C5;
+static const field core::int* doubleTruncateDiv = #C3;
+static const field core::int* doubleTruncateDivZero = invalid-expression "Binary operator '~/' on '84.2' requires non-zero divisor, but divisor was '0'.";
+static const field core::int* doubleTruncateDivNull = invalid-expression "Binary operator '~/' on '84.2' requires operand of type 'num', but was of type 'Null'.";
+static const field core::double* doubleNan = #C7;
+static const field core::int* doubleTruncateDivNaN = invalid-expression "Binary operator '84.2 ~/ NaN' results is Infinity or NaN.";
+static method main() → dynamic {}
+
+constants  {
+  #C1 = -2
+  #C2 = -3
+  #C3 = 42
+  #C4 = 42.0
+  #C5 = false
+  #C6 = true
+  #C7 = NaN
+}
diff --git a/pkg/front_end/testcases/general/constants/potentially_constant_type.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/potentially_constant_type.dart.weak.modular.expect
new file mode 100644
index 0000000..35d93a3
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/potentially_constant_type.dart.weak.modular.expect
@@ -0,0 +1,666 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:26:18: Error: Type variables can't be used as constants.
+//       : field1 = T,
+//                  ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:27:21: Error: Constant expression expected.
+// Try inserting 'const'.
+//         field5 = <T>[],
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:27:19: Error: Type variables can't be used as constants.
+//         field5 = <T>[],
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:28:21: Error: Constant expression expected.
+// Try inserting 'const'.
+//         field6 = <T>{},
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:28:19: Error: Type variables can't be used as constants.
+//         field6 = <T>{},
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:29:24: Error: Constant expression expected.
+// Try inserting 'const'.
+//         field7 = <T, T>{},
+//                        ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:29:19: Error: Type variables can't be used as constants.
+//         field7 = <T, T>{},
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:29:22: Error: Type variables can't be used as constants.
+//         field7 = <T, T>{},
+//                      ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:30:23: Error: Type variables can't be used as constants.
+//         field8 = o is T,
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:31:29: Error: Type variables can't be used as constants.
+//         field9 = o is Class<T>,
+//                             ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:32:24: Error: Type variables can't be used as constants.
+//         field10 = o as T,
+//                        ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:33:30: Error: Type variables can't be used as constants.
+//         field11 = o as Class<T>,
+//                              ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:34:26: Error: Type variables can't be used as constants.
+//         field15 = <Class<T>>[];
+//                          ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:34:29: Error: Constant expression expected.
+// Try inserting 'const'.
+//         field15 = <Class<T>>[];
+//                             ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:40:20: Error: Type variables can't be used as constants.
+//     const local1 = T;
+//                    ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:41:21: Error: Type variables can't be used as constants.
+//     const local5 = <T>[];
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:42:21: Error: Type variables can't be used as constants.
+//     const local6 = <T>{};
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:43:21: Error: Type variables can't be used as constants.
+//     const local7 = <T, T>{};
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:43:24: Error: Type variables can't be used as constants.
+//     const local7 = <T, T>{};
+//                        ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:44:25: Error: Type variables can't be used as constants.
+//     const local8 = o is T;
+//                         ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:45:31: Error: Type variables can't be used as constants.
+//     const local9 = o is Class<T>;
+//                               ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:46:26: Error: Type variables can't be used as constants.
+//     const local10 = o as T;
+//                          ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:47:32: Error: Type variables can't be used as constants.
+//     const local11 = o as Class<T>;
+//                                ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:48:28: Error: Type variables can't be used as constants.
+//     const local15 = <Class<T>>[];
+//                            ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:63:18: Error: Type variables can't be used as constants.
+//     print(const [T]);
+//                  ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:64:19: Error: Type variables can't be used as constants.
+//     print(const [<T>[]]);
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:65:19: Error: Type variables can't be used as constants.
+//     print(const [<T>{}]);
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:66:19: Error: Type variables can't be used as constants.
+//     print(const [<T, T>{}]);
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:66:22: Error: Type variables can't be used as constants.
+//     print(const [<T, T>{}]);
+//                      ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:67:23: Error: Type variables can't be used as constants.
+//     print(const [o is T]);
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:68:29: Error: Type variables can't be used as constants.
+//     print(const [o is Class<T>]);
+//                             ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:69:23: Error: Type variables can't be used as constants.
+//     print(const [o as T]);
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:70:29: Error: Type variables can't be used as constants.
+//     print(const [o as Class<T>]);
+//                             ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type.dart:71:25: Error: Type variables can't be used as constants.
+//     print(const [<Class<T>>[]]);
+//                         ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///potentially_constant_type_lib1.dart";
+import "org-dartlang-testcase:///potentially_constant_type_lib2.dart";
+
+class Class<T extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field dynamic field1;
+  final field dynamic field5;
+  final field dynamic field6;
+  final field dynamic field7;
+  final field dynamic field8;
+  final field dynamic field9;
+  final field dynamic field10;
+  final field dynamic field11;
+  final field dynamic field15;
+  const constructor •(dynamic o) → self::Class<self::Class::T*>*
+    : self::Class::field1 = #C1, self::Class::field5 = #C2, self::Class::field6 = #C3, self::Class::field7 = #C4, self::Class::field8 = o is invalid-type, self::Class::field9 = o is self::Class<invalid-type>*, self::Class::field10 = o as invalid-type, self::Class::field11 = o as self::Class<invalid-type>*, self::Class::field15 = #C5, super core::Object::•()
+    ;
+  method method() → void {
+    core::print(#C1);
+    core::print(#C2);
+    core::print(#C3);
+    core::print(#C4);
+    core::print(#C6);
+    core::print(#C7);
+    core::print(#C8);
+    core::print(#C8);
+    core::print(#C5);
+    core::print(#C9);
+    core::print(#C10);
+    core::print(#C11);
+    core::print(#C12);
+    core::print(#C13);
+    core::print(#C14);
+    core::print(#C15);
+    core::print(#C16);
+    core::print(#C17);
+    core::print(#C18);
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method id<T extends core::Object* = dynamic>(self::id::T* t) → self::id::T*
+  return t;
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:23:18: Error: Type variables can't be used as constants.
+//       : field1 = T,
+//                  ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:24:21: Error: Constant expression expected.
+// Try inserting 'const'.
+//         field5 = <T>[],
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:24:19: Error: Type variables can't be used as constants.
+//         field5 = <T>[],
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:25:21: Error: Constant expression expected.
+// Try inserting 'const'.
+//         field6 = <T>{},
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:25:19: Error: Type variables can't be used as constants.
+//         field6 = <T>{},
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:26:24: Error: Constant expression expected.
+// Try inserting 'const'.
+//         field7 = <T, T>{},
+//                        ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:26:19: Error: Type variables can't be used as constants.
+//         field7 = <T, T>{},
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:26:22: Error: Type variables can't be used as constants.
+//         field7 = <T, T>{},
+//                      ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:31:26: Error: Type variables can't be used as constants.
+//         field15 = <Class<T>>[];
+//                          ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:31:29: Error: Constant expression expected.
+// Try inserting 'const'.
+//         field15 = <Class<T>>[];
+//                             ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:37:20: Error: Type variables can't be used as constants.
+//     const local1 = T;
+//                    ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:38:21: Error: Type variables can't be used as constants.
+//     const local5 = <T>[];
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:39:21: Error: Type variables can't be used as constants.
+//     const local6 = <T>{};
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:40:21: Error: Type variables can't be used as constants.
+//     const local7 = <T, T>{};
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:40:24: Error: Type variables can't be used as constants.
+//     const local7 = <T, T>{};
+//                        ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:41:25: Error: Type variables can't be used as constants.
+//     const local8 = o is T;
+//                         ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:42:31: Error: Type variables can't be used as constants.
+//     const local9 = o is Class<T>;
+//                               ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:43:26: Error: Type variables can't be used as constants.
+//     const local10 = o as T;
+//                          ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:44:32: Error: Type variables can't be used as constants.
+//     const local11 = o as Class<T>;
+//                                ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:45:28: Error: Type variables can't be used as constants.
+//     const local15 = <Class<T>>[];
+//                            ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:60:18: Error: Type variables can't be used as constants.
+//     print(const [T]);
+//                  ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:61:19: Error: Type variables can't be used as constants.
+//     print(const [<T>[]]);
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:62:19: Error: Type variables can't be used as constants.
+//     print(const [<T>{}]);
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:63:19: Error: Type variables can't be used as constants.
+//     print(const [<T, T>{}]);
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:63:22: Error: Type variables can't be used as constants.
+//     print(const [<T, T>{}]);
+//                      ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:64:23: Error: Type variables can't be used as constants.
+//     print(const [o is T]);
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:65:29: Error: Type variables can't be used as constants.
+//     print(const [o is Class<T>]);
+//                             ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:66:23: Error: Type variables can't be used as constants.
+//     print(const [o as T]);
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:67:29: Error: Type variables can't be used as constants.
+//     print(const [o as Class<T>]);
+//                             ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib1.dart:68:25: Error: Type variables can't be used as constants.
+//     print(const [<Class<T>>[]]);
+//                         ^
+//
+import self as self2;
+import "dart:core" as core;
+
+class Class<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field dynamic field1;
+  final field dynamic field5;
+  final field dynamic field6;
+  final field dynamic field7;
+  final field dynamic field8;
+  final field dynamic field9;
+  final field dynamic field10;
+  final field dynamic field11;
+  final field dynamic field15;
+  const constructor •(dynamic o) → self2::Class<self2::Class::T%>
+    : self2::Class::field1 = #C1, self2::Class::field5 = #C2, self2::Class::field6 = #C3, self2::Class::field7 = #C4, self2::Class::field8 = o is{ForNonNullableByDefault} self2::Class::T%, self2::Class::field9 = o is{ForNonNullableByDefault} self2::Class<self2::Class::T%>, self2::Class::field10 = o as{ForNonNullableByDefault} self2::Class::T%, self2::Class::field11 = o{self2::Class::T%} as{ForNonNullableByDefault} self2::Class<self2::Class::T%>, self2::Class::field15 = #C19, super core::Object::•()
+    ;
+  method method() → void {
+    core::print(#C1);
+    core::print(#C2);
+    core::print(#C3);
+    core::print(#C4);
+    core::print(#C6);
+    core::print(#C7);
+    core::print(#C8);
+    core::print(#C8);
+    core::print(#C19);
+    core::print(#C20);
+    core::print(#C10);
+    core::print(#C11);
+    core::print(#C12);
+    core::print(#C13);
+    core::print(#C14);
+    core::print(#C15);
+    core::print(#C21);
+    core::print(#C22);
+    core::print(#C23);
+  }
+}
+static method id<T extends core::Object? = dynamic>(self2::id::T% t) → self2::id::T%
+  return t;
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:34:21: Error: Constant expression expected.
+// Try inserting 'const'.
+//         field5 = <T>[],
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:34:19: Error: Type variables can't be used as constants.
+//         field5 = <T>[],
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:35:21: Error: Constant expression expected.
+// Try inserting 'const'.
+//         field6 = <T>{},
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:35:19: Error: Type variables can't be used as constants.
+//         field6 = <T>{},
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:36:24: Error: Constant expression expected.
+// Try inserting 'const'.
+//         field7 = <T, T>{},
+//                        ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:36:19: Error: Type variables can't be used as constants.
+//         field7 = <T, T>{},
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:36:22: Error: Type variables can't be used as constants.
+//         field7 = <T, T>{},
+//                      ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:44:29: Error: Constant expression expected.
+// Try inserting 'const'.
+//         field15 = <Class<T>>[],
+//                             ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:44:26: Error: Type variables can't be used as constants.
+//         field15 = <Class<T>>[],
+//                          ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:51:20: Error: Type variables can't be used as constants.
+//     const local1 = T;
+//                    ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:52:26: Error: Type variables can't be used as constants.
+//     const local2 = Class<T>;
+//                          ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:53:23: Error: Type variables can't be used as constants.
+//     const local3 = id<T>;
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:54:25: Error: Type variables can't be used as constants.
+//     const local4 = (id)<T>;
+//                         ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:55:21: Error: Type variables can't be used as constants.
+//     const local5 = <T>[];
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:56:21: Error: Type variables can't be used as constants.
+//     const local6 = <T>{};
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:57:21: Error: Type variables can't be used as constants.
+//     const local7 = <T, T>{};
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:57:24: Error: Type variables can't be used as constants.
+//     const local7 = <T, T>{};
+//                        ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:58:25: Error: Type variables can't be used as constants.
+//     const local8 = o is T;
+//                         ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:59:31: Error: Type variables can't be used as constants.
+//     const local9 = o is Class<T>;
+//                               ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:60:26: Error: Type variables can't be used as constants.
+//     const local10 = o as T;
+//                          ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:61:32: Error: Type variables can't be used as constants.
+//     const local11 = o as Class<T>;
+//                                ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:62:27: Error: Type variables can't be used as constants.
+//     const local12 = Class<T>.new;
+//                           ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:63:23: Error: Type variables can't be used as constants.
+//     const local13 = F<T, T>.new;
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:63:26: Error: Type variables can't be used as constants.
+//     const local13 = F<T, T>.new;
+//                          ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:64:30: Error: Type variables can't be used as constants.
+//     const local14 = id<Class<T>>;
+//                              ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:65:28: Error: Type variables can't be used as constants.
+//     const local15 = <Class<T>>[];
+//                            ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:66:23: Error: Type variables can't be used as constants.
+//     const local16 = G<T>.new;
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:88:18: Error: Type variables can't be used as constants.
+//     print(const [T]);
+//                  ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:89:24: Error: Type variables can't be used as constants.
+//     print(const [Class<T>]);
+//                        ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:90:21: Error: Type variables can't be used as constants.
+//     print(const [id<T>]);
+//                     ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:91:23: Error: Type variables can't be used as constants.
+//     print(const [(id)<T>]);
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:92:19: Error: Type variables can't be used as constants.
+//     print(const [<T>[]]);
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:93:19: Error: Type variables can't be used as constants.
+//     print(const [<T>{}]);
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:94:19: Error: Type variables can't be used as constants.
+//     print(const [<T, T>{}]);
+//                   ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:94:22: Error: Type variables can't be used as constants.
+//     print(const [<T, T>{}]);
+//                      ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:95:23: Error: Type variables can't be used as constants.
+//     print(const [o is T]);
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:96:29: Error: Type variables can't be used as constants.
+//     print(const [o is Class<T>]);
+//                             ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:97:23: Error: Type variables can't be used as constants.
+//     print(const [o as T]);
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:98:29: Error: Type variables can't be used as constants.
+//     print(const [o as Class<T>]);
+//                             ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:99:24: Error: Type variables can't be used as constants.
+//     print(const [Class<T>.new]);
+//                        ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:100:20: Error: Type variables can't be used as constants.
+//     print(const [F<T, T>.new]);
+//                    ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:100:23: Error: Type variables can't be used as constants.
+//     print(const [F<T, T>.new]);
+//                       ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:101:27: Error: Type variables can't be used as constants.
+//     print(const [id<Class<T>>]);
+//                           ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:102:25: Error: Type variables can't be used as constants.
+//     print(const [<Class<T>>[]]);
+//                         ^
+//
+// pkg/front_end/testcases/general/constants/potentially_constant_type_lib2.dart:103:20: Error: Type variables can't be used as constants.
+//     print(const [G<T>.new]);
+//                    ^
+//
+import self as self3;
+import "dart:core" as core;
+
+typedef F<X extends core::Object? = dynamic, unrelated Y extends core::Object? = dynamic> = self3::Class<X%>;
+typedef G<unrelated X extends core::Object? = dynamic> = self3::Class<core::int>;
+class Class<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field dynamic field1;
+  final field dynamic field2;
+  final field dynamic field3;
+  final field dynamic field4;
+  final field dynamic field5;
+  final field dynamic field6;
+  final field dynamic field7;
+  final field dynamic field8;
+  final field dynamic field9;
+  final field dynamic field10;
+  final field dynamic field11;
+  final field dynamic field12;
+  final field dynamic field13;
+  final field dynamic field14;
+  final field dynamic field15;
+  final field dynamic field16;
+  const constructor •(dynamic o) → self3::Class<self3::Class::T%>
+    : self3::Class::field1 = self3::Class::T%, self3::Class::field2 = self3::Class<self3::Class::T%>, self3::Class::field3 = #C24<self3::Class::T%>, self3::Class::field4 = #C24<self3::Class::T%>, self3::Class::field5 = #C2, self3::Class::field6 = #C3, self3::Class::field7 = #C4, self3::Class::field8 = o is{ForNonNullableByDefault} self3::Class::T%, self3::Class::field9 = o is{ForNonNullableByDefault} self3::Class<self3::Class::T%>, self3::Class::field10 = o as{ForNonNullableByDefault} self3::Class::T%, self3::Class::field11 = o{self3::Class::T%} as{ForNonNullableByDefault} self3::Class<self3::Class::T%>, self3::Class::field12 = #C25<self3::Class::T%>, self3::Class::field13 = #C25<self3::Class::T%>, self3::Class::field14 = #C24<self3::Class<self3::Class::T%>>, self3::Class::field15 = #C26, self3::Class::field16 = #C27, super core::Object::•()
+    ;
+  method method() → void {
+    core::print(#C1);
+    core::print(#C28);
+    core::print(#C29);
+    core::print(#C29);
+    core::print(#C2);
+    core::print(#C3);
+    core::print(#C4);
+    core::print(#C6);
+    core::print(#C7);
+    core::print(#C8);
+    core::print(#C8);
+    core::print(#C30);
+    core::print(#C30);
+    core::print(#C31);
+    core::print(#C26);
+    core::print(#C27);
+    core::print(#C20);
+    core::print(#C10);
+    core::print(#C32);
+    core::print(#C33);
+    core::print(#C33);
+    core::print(#C11);
+    core::print(#C12);
+    core::print(#C13);
+    core::print(#C14);
+    core::print(#C15);
+    core::print(#C21);
+    core::print(#C34);
+    core::print(#C35);
+    core::print(#C35);
+    core::print(#C36);
+    core::print(#C37);
+    core::print(#C38);
+  }
+}
+static method id<T extends core::Object? = dynamic>(self3::id::T% t) → self3::id::T%
+  return t;
+static method main() → dynamic {}
+static method _#F#new#tearOff<X extends core::Object? = dynamic, unrelated Y extends core::Object? = dynamic>(dynamic o) → self3::Class<self3::_#F#new#tearOff::X%>
+  return new self3::Class::•<self3::_#F#new#tearOff::X%>(o);
+static method _#G#new#tearOff<unrelated X extends core::Object? = dynamic>(dynamic o) → self3::Class<core::int>
+  return new self3::Class::•<core::int>(o);
+
+constants  {
+  #C1 = TypeLiteralConstant(invalid-type)
+  #C2 = <invalid-type>[]
+  #C3 = <invalid-type>{}
+  #C4 = <invalid-type, invalid-type>{)
+  #C5 = <self::Class<invalid-type>*>[]
+  #C6 = true
+  #C7 = false
+  #C8 = null
+  #C9 = <Null>[]
+  #C10 = <core::Type*>[#C1]
+  #C11 = <core::List<invalid-type>*>[#C2]
+  #C12 = <core::Set<invalid-type>*>[#C3]
+  #C13 = <core::Map<invalid-type, invalid-type>*>[#C4]
+  #C14 = <core::bool*>[#C6]
+  #C15 = <core::bool*>[#C7]
+  #C16 = <invalid-type>[#C8]
+  #C17 = <self::Class<invalid-type>*>[#C8]
+  #C18 = <core::List<self::Class<invalid-type>*>*>[#C5]
+  #C19 = <self2::Class<invalid-type>*>[]
+  #C20 = <Never*>[]
+  #C21 = <dynamic>[#C8]
+  #C22 = <self2::Class<invalid-type>*>[#C8]
+  #C23 = <core::List<self2::Class<invalid-type>*>*>[#C19]
+  #C24 = static-tearoff self3::id
+  #C25 = constructor-tearoff self3::Class::•
+  #C26 = <self3::Class<invalid-type>*>[]
+  #C27 = instantiation #C25 <core::int*>
+  #C28 = TypeLiteralConstant(self3::Class<invalid-type>*)
+  #C29 = instantiation #C24 <invalid-type>
+  #C30 = instantiation #C25 <invalid-type>
+  #C31 = instantiation #C24 <self3::Class<invalid-type>*>
+  #C32 = <core::Type*>[#C28]
+  #C33 = <(invalid-type) →* invalid-type>[#C29]
+  #C34 = <self3::Class<invalid-type>*>[#C8]
+  #C35 = <(dynamic) →* self3::Class<invalid-type>*>[#C30]
+  #C36 = <(self3::Class<invalid-type>*) →* self3::Class<invalid-type>*>[#C31]
+  #C37 = <core::List<self3::Class<invalid-type>*>*>[#C26]
+  #C38 = <(dynamic) →* self3::Class<core::int*>*>[#C27]
+}
diff --git a/pkg/front_end/testcases/general/constants/rudimentary_test_01.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/rudimentary_test_01.dart.weak.modular.expect
new file mode 100644
index 0000000..f3b74df
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/rudimentary_test_01.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static const field core::int* foo = #C1;
+static const field core::String* bar = #C2;
+static const field core::String* bar2 = #C3;
+static const field core::bool* baz = #C4;
+static const field core::Symbol* blaSymbol = #C5;
+static method main() → dynamic {
+  self::_x();
+  #C6;
+  core::print(#C2);
+}
+static method _x() → void {
+  core::print(#C1);
+  core::print(#C2);
+}
+
+constants  {
+  #C1 = 1764
+  #C2 = "hello 42!"
+  #C3 = "hello2 2hello 42!"
+  #C4 = true
+  #C5 = #org-dartlang-testcase:///rudimentary_test_01.dart::_x
+  #C6 = false
+}
diff --git a/pkg/front_end/testcases/general/constants/various.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/various.dart.weak.modular.expect
new file mode 100644
index 0000000..9fa5cbe
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/various.dart.weak.modular.expect
@@ -0,0 +1,644 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/various.dart:162:3: Error: A const constructor can't have a body.
+// Try removing either the 'const' keyword or the body.
+//   const ClassWithNonEmptyConstConstructor() {
+//   ^^^^^
+//
+// pkg/front_end/testcases/general/constants/various.dart:76:14: Error: Not a constant expression.
+// const x1 = --x;
+//              ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:77:14: Error: Not a constant expression.
+// const x2 = ++x;
+//              ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:78:12: Error: Not a constant expression.
+// const x3 = x--;
+//            ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:79:12: Error: Not a constant expression.
+// const x4 = x++;
+//            ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:82:14: Error: Setter not found: 'y'.
+// const y1 = --y;
+//              ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:83:14: Error: Setter not found: 'y'.
+// const y2 = ++y;
+//              ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:84:12: Error: Setter not found: 'y'.
+// const y3 = y--;
+//            ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:85:12: Error: Setter not found: 'y'.
+// const y4 = y++;
+//            ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:140:24: Error: Not a constant expression.
+// const function_const = () {};
+//                        ^^
+//
+// pkg/front_end/testcases/general/constants/various.dart:180:14: Error: Can't access 'this' in a field initializer to read 'y'.
+//   final z1 = y;
+//              ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:99:4: Error: The class 'AbstractClass' is abstract and can't be instantiated.
+//   @AbstractClass()
+//    ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/constants/various.dart:99:4: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+// Try using a constructor or factory that is 'const'.
+//   @AbstractClass()
+//    ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:102:4: Error: The class 'AbstractClassWithConstructor' is abstract and can't be instantiated.
+//   @AbstractClassWithConstructor()
+//    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/constants/various.dart:102:4: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+// Try using a constructor or factory that is 'const'.
+//   @AbstractClassWithConstructor()
+//    ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:118:39: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+// Try using a constructor or factory that is 'const'.
+// const ExtendsFoo1 extendsFoo1 = const ExtendsFoo1();
+//                                       ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/constants/various.dart:121:9: Error: The superclass, 'Foo', has no unnamed constructor that takes no arguments.
+//   const ExtendsFoo2();
+//         ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/constants/various.dart:180:14: Error: Not a constant expression.
+//   final z1 = y;
+//              ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:181:14: Error: Not a constant expression.
+//   final z2 = x;
+//              ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:96:11: Error: The class 'AbstractClassWithConstructor' is abstract and can't be instantiated.
+//     const AbstractClassWithConstructor();
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/constants/various.dart:96:11: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+// Try using a constructor or factory that is 'const'.
+//     const AbstractClassWithConstructor();
+//           ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:168:11: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+// Try using a constructor or factory that is 'const'.
+//     const ClassWithNonEmptyConstConstructor();
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/constants/various.dart:114:7: Error: The superclass, 'Foo', has no unnamed constructor that takes no arguments.
+// class ExtendsFoo1 extends Foo {
+//       ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:99:4: Error: Not a constant expression.
+//   @AbstractClass()
+//    ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:102:4: Error: Not a constant expression.
+//   @AbstractClassWithConstructor()
+//    ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:10:34: Error: Constant evaluation error:
+// const bool notBarFromEnvOrNull = !barFromEnvOrNull;
+//                                  ^
+// pkg/front_end/testcases/general/constants/various.dart:10:34: Context: Expected constant 'null' to be of type 'bool', but was of type 'Null'.
+// const bool notBarFromEnvOrNull = !barFromEnvOrNull;
+//                                  ^
+// pkg/front_end/testcases/general/constants/various.dart:10:12: Context: While analyzing:
+// const bool notBarFromEnvOrNull = !barFromEnvOrNull;
+//            ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:11:49: Error: Constant evaluation error:
+// const bool conditionalOnNull = barFromEnvOrNull ? true : false;
+//                                                 ^
+// pkg/front_end/testcases/general/constants/various.dart:11:32: Context: Expected constant 'null' to be of type 'bool', but was of type 'Null'.
+// const bool conditionalOnNull = barFromEnvOrNull ? true : false;
+//                                ^
+// pkg/front_end/testcases/general/constants/various.dart:11:12: Context: While analyzing:
+// const bool conditionalOnNull = barFromEnvOrNull ? true : false;
+//            ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:16:41: Error: Constant evaluation error:
+// const bool andOnNull = barFromEnvOrNull && true;
+//                                         ^
+// pkg/front_end/testcases/general/constants/various.dart:16:41: Context: The method '&&' can't be invoked on 'null' in a constant expression.
+// const bool andOnNull = barFromEnvOrNull && true;
+//                                         ^
+// pkg/front_end/testcases/general/constants/various.dart:16:12: Context: While analyzing:
+// const bool andOnNull = barFromEnvOrNull && true;
+//            ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:17:30: Error: Constant evaluation error:
+// const bool andOnNull2 = true && barFromEnvOrNull;
+//                              ^
+// pkg/front_end/testcases/general/constants/various.dart:17:30: Context: Binary operator '&&' on 'true' requires operand of type 'bool', but was of type 'Null'.
+// const bool andOnNull2 = true && barFromEnvOrNull;
+//                              ^
+// pkg/front_end/testcases/general/constants/various.dart:17:12: Context: While analyzing:
+// const bool andOnNull2 = true && barFromEnvOrNull;
+//            ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:18:40: Error: Constant evaluation error:
+// const bool orOnNull = barFromEnvOrNull || true;
+//                                        ^
+// pkg/front_end/testcases/general/constants/various.dart:18:40: Context: The method '||' can't be invoked on 'null' in a constant expression.
+// const bool orOnNull = barFromEnvOrNull || true;
+//                                        ^
+// pkg/front_end/testcases/general/constants/various.dart:18:12: Context: While analyzing:
+// const bool orOnNull = barFromEnvOrNull || true;
+//            ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:19:41: Error: Constant evaluation error:
+// const bool orOnNull2 = barFromEnvOrNull || false;
+//                                         ^
+// pkg/front_end/testcases/general/constants/various.dart:19:41: Context: The method '||' can't be invoked on 'null' in a constant expression.
+// const bool orOnNull2 = barFromEnvOrNull || false;
+//                                         ^
+// pkg/front_end/testcases/general/constants/various.dart:19:12: Context: While analyzing:
+// const bool orOnNull2 = barFromEnvOrNull || false;
+//            ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:21:30: Error: Constant evaluation error:
+// const bool orOnNull4 = false || barFromEnvOrNull;
+//                              ^
+// pkg/front_end/testcases/general/constants/various.dart:21:30: Context: Binary operator '||' on 'false' requires operand of type 'bool', but was of type 'Null'.
+// const bool orOnNull4 = false || barFromEnvOrNull;
+//                              ^
+// pkg/front_end/testcases/general/constants/various.dart:21:12: Context: While analyzing:
+// const bool orOnNull4 = false || barFromEnvOrNull;
+//            ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:29:11: Error: Constant evaluation error:
+//     const String.fromEnvironment(barFromEnvOrNullString);
+//           ^
+// pkg/front_end/testcases/general/constants/various.dart:29:11: Context: Null value during constant evaluation.
+//     const String.fromEnvironment(barFromEnvOrNullString);
+//           ^
+// pkg/front_end/testcases/general/constants/various.dart:28:14: Context: While analyzing:
+// const String nullFromEnvString =
+//              ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:36:36: Error: Constant evaluation error:
+// const bool nullFromEnvBool = const bool.fromEnvironment(barFromEnvOrNullString);
+//                                    ^
+// pkg/front_end/testcases/general/constants/various.dart:36:36: Context: Null value during constant evaluation.
+// const bool nullFromEnvBool = const bool.fromEnvironment(barFromEnvOrNullString);
+//                                    ^
+// pkg/front_end/testcases/general/constants/various.dart:36:12: Context: While analyzing:
+// const bool nullFromEnvBool = const bool.fromEnvironment(barFromEnvOrNullString);
+//            ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:43:34: Error: Constant evaluation error:
+// const int nullFromEnvInt = const int.fromEnvironment(barFromEnvOrNullString);
+//                                  ^
+// pkg/front_end/testcases/general/constants/various.dart:43:34: Context: Null value during constant evaluation.
+// const int nullFromEnvInt = const int.fromEnvironment(barFromEnvOrNullString);
+//                                  ^
+// pkg/front_end/testcases/general/constants/various.dart:43:11: Context: While analyzing:
+// const int nullFromEnvInt = const int.fromEnvironment(barFromEnvOrNullString);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:64:37: Error: Constant evaluation error:
+// const binaryOnDouble = willBeDouble << 2;
+//                                     ^
+// pkg/front_end/testcases/general/constants/various.dart:64:37: Context: Binary operator '<<' on '42.42' requires operand of type 'int', but was of type 'double'.
+// const binaryOnDouble = willBeDouble << 2;
+//                                     ^
+// pkg/front_end/testcases/general/constants/various.dart:64:7: Context: While analyzing:
+// const binaryOnDouble = willBeDouble << 2;
+//       ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:66:44: Error: Constant evaluation error:
+// const binaryOnIntWithDoubleBad = willBeInt << willBeDouble;
+//                                            ^
+// pkg/front_end/testcases/general/constants/various.dart:66:44: Context: Binary operator '<<' on '42.42' requires operand of type 'int', but was of type 'double'.
+// const binaryOnIntWithDoubleBad = willBeInt << willBeDouble;
+//                                            ^
+// pkg/front_end/testcases/general/constants/various.dart:66:7: Context: While analyzing:
+// const binaryOnIntWithDoubleBad = willBeInt << willBeDouble;
+//       ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:68:41: Error: Constant evaluation error:
+// const binaryOnIntWithString = willBeInt << "hello";
+//                                         ^
+// pkg/front_end/testcases/general/constants/various.dart:68:41: Context: Binary operator '<<' on '42' requires operand of type 'num', but was of type 'String'.
+// const binaryOnIntWithString = willBeInt << "hello";
+//                                         ^
+// pkg/front_end/testcases/general/constants/various.dart:68:7: Context: While analyzing:
+// const binaryOnIntWithString = willBeInt << "hello";
+//       ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:72:44: Error: Constant evaluation error:
+// const binaryOnStringWithInt = willBeString + willBeInt;
+//                                            ^
+// pkg/front_end/testcases/general/constants/various.dart:72:44: Context: Binary operator '+' on '"hello"' requires operand of type 'String', but was of type 'int'.
+// const binaryOnStringWithInt = willBeString + willBeInt;
+//                                            ^
+// pkg/front_end/testcases/general/constants/various.dart:72:7: Context: While analyzing:
+// const binaryOnStringWithInt = willBeString + willBeInt;
+//       ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:73:50: Error: Constant evaluation error:
+// const binaryOnStringWithStringBad = willBeString - " world";
+//                                                  ^
+// pkg/front_end/testcases/general/constants/various.dart:73:50: Context: The method '-' can't be invoked on '"hello"' in a constant expression.
+// const binaryOnStringWithStringBad = willBeString - " world";
+//                                                  ^
+// pkg/front_end/testcases/general/constants/various.dart:73:7: Context: While analyzing:
+// const binaryOnStringWithStringBad = willBeString - " world";
+//       ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:78:13: Error: Constant evaluation error:
+// const x3 = x--;
+//             ^
+// pkg/front_end/testcases/general/constants/various.dart:78:12: Context: The invocation of 'x' is not allowed in a constant expression.
+// const x3 = x--;
+//            ^
+// pkg/front_end/testcases/general/constants/various.dart:78:7: Context: While analyzing:
+// const x3 = x--;
+//       ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:79:13: Error: Constant evaluation error:
+// const x4 = x++;
+//             ^
+// pkg/front_end/testcases/general/constants/various.dart:79:12: Context: The invocation of 'x' is not allowed in a constant expression.
+// const x4 = x++;
+//            ^
+// pkg/front_end/testcases/general/constants/various.dart:79:7: Context: While analyzing:
+// const x4 = x++;
+//       ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:129:29: Error: Constant evaluation error:
+// const bool foosEqual = foo1 == foo2;
+//                             ^
+// pkg/front_end/testcases/general/constants/various.dart:129:29: Context: Binary operator '==' requires receiver constant 'Foo {x: 42, y: 5}' of type 'Null', 'bool', 'int', 'double', or 'String', but was of type 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/constants/various.dart'.
+// const bool foosEqual = foo1 == foo2;
+//                             ^
+// pkg/front_end/testcases/general/constants/various.dart:129:12: Context: While analyzing:
+// const bool foosEqual = foo1 == foo2;
+//            ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:135:26: Error: Constant evaluation error:
+// const int circularity1 = circularity2;
+//                          ^
+// pkg/front_end/testcases/general/constants/various.dart:135:26: Context: Constant expression depends on itself.
+// const int circularity1 = circularity2;
+//                          ^
+// pkg/front_end/testcases/general/constants/various.dart:135:11: Context: While analyzing:
+// const int circularity1 = circularity2;
+//           ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:148:11: Error: Constant evaluation error:
+//     const ConstClassWithFailingAssertWithEmptyMessage();
+//           ^
+// pkg/front_end/testcases/general/constants/various.dart:144:64: Context: This assertion failed with message: (empty)
+//   const ConstClassWithFailingAssertWithEmptyMessage() : assert(false, "");
+//                                                                ^
+//
+// pkg/front_end/testcases/general/constants/various.dart:185:11: Error: Constant evaluation error:
+//     const ConstClassWithFinalFields2();
+//           ^
+// pkg/front_end/testcases/general/constants/various.dart:181:14: Context: The invocation of 'x' is not allowed in a constant expression.
+//   final z2 = x;
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+abstract class AbstractClass extends core::Object {
+  synthetic constructor •() → self::AbstractClass*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class AbstractClassWithConstructor extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::AbstractClassWithConstructor*
+    : super core::Object::•()
+    ;
+  abstract method foo() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class NotAbstractClass extends core::Object {
+  @invalid-expression "Not a constant expression."
+  field core::Object* foo = null;
+  @invalid-expression "Not a constant expression."
+  field core::Object* bar = null;
+  synthetic constructor •() → self::NotAbstractClass*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Foo extends core::Object /*hasConstConstructor*/  {
+  final field core::int* x;
+  final field core::int* y;
+  const constructor •(core::int* x) → self::Foo*
+    : self::Foo::x = x, self::Foo::y = "hello".{core::String::length}{core::int*}, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class ExtendsFoo1 extends self::Foo {
+  synthetic constructor •() → self::ExtendsFoo1*
+    : invalid-initializer
+    ;
+}
+class ExtendsFoo2 extends self::Foo /*hasConstConstructor*/  {
+  const constructor •() → self::ExtendsFoo2*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/constants/various.dart:121:9: Error: The superclass, 'Foo', has no unnamed constructor that takes no arguments.
+  const ExtendsFoo2();
+        ^^^^^^^^^^^"
+    ;
+}
+class ConstClassWithFailingAssertWithEmptyMessage extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::ConstClassWithFailingAssertWithEmptyMessage*
+    : assert(false, ""), super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class ClassWithTypeArguments<E extends core::Object* = dynamic, F extends core::Object* = dynamic, G extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const constructor •(self::ClassWithTypeArguments::E* e, self::ClassWithTypeArguments::F* f, self::ClassWithTypeArguments::G* g) → self::ClassWithTypeArguments<self::ClassWithTypeArguments::E*, self::ClassWithTypeArguments::F*, self::ClassWithTypeArguments::G*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class ClassWithNonEmptyConstConstructor extends core::Object {
+  constructor •() → self::ClassWithNonEmptyConstConstructor*
+    : super core::Object::•() {
+    core::print("hello");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class ConstClassWithFinalFields1 extends core::Object /*hasConstConstructor*/  {
+  final field core::int* x = 1;
+  const constructor •() → self::ConstClassWithFinalFields1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class ConstClassWithFinalFields2 extends core::Object /*hasConstConstructor*/  {
+  final field core::int* y = 1;
+  final field invalid-type z1 = this.{self::ConstClassWithFinalFields2::y}{core::int*};
+  final field core::int* z2 = self::x;
+  const constructor •() → self::ConstClassWithFinalFields2*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field core::bool* barFromEnv = #C1;
+static const field core::bool* hasBarEnv = #C1;
+static const field core::bool* barFromEnvOrNull = #C2;
+static const field core::bool* notBarFromEnvOrNull = invalid-expression "Expected constant 'null' to be of type 'bool', but was of type 'Null'.";
+static const field core::bool* conditionalOnNull = invalid-expression "Expected constant 'null' to be of type 'bool', but was of type 'Null'.";
+static const field core::bool* nullAwareOnNullTrue = #C3;
+static const field core::bool* nullAwareOnNullFalse = #C1;
+static const field core::bool* andOnFalse = #C1;
+static const field core::bool* andOnFalse2 = #C1;
+static const field core::bool* andOnNull = invalid-expression "The method '&&' can't be invoked on 'null' in a constant expression.";
+static const field core::bool* andOnNull2 = invalid-expression "Binary operator '&&' on 'true' requires operand of type 'bool', but was of type 'Null'.";
+static const field core::bool* orOnNull = invalid-expression "The method '||' can't be invoked on 'null' in a constant expression.";
+static const field core::bool* orOnNull2 = invalid-expression "The method '||' can't be invoked on 'null' in a constant expression.";
+static const field core::bool* orOnNull3 = #C3;
+static const field core::bool* orOnNull4 = invalid-expression "Binary operator '||' on 'false' requires operand of type 'bool', but was of type 'Null'.";
+static const field core::String* barFromEnvString = #C4;
+static const field core::String* barFromEnvOrNullString = #C2;
+static const field core::String* barFromEnvOrActualString = #C5;
+static const field core::String* nullFromEnvString = invalid-expression "Null value during constant evaluation.";
+static const field core::bool* barFromEnvBool = #C1;
+static const field core::bool* barFromEnvOrNullBool = #C2;
+static const field core::bool* barFromEnvOrActualBool = #C3;
+static const field core::bool* nullFromEnvBool = invalid-expression "Null value during constant evaluation.";
+static const field core::int* barFromEnvInt = #C6;
+static const field core::int* barFromEnvOrNullInt = #C2;
+static const field core::int* barFromEnvOrActualInt = #C7;
+static const field core::int* nullFromEnvInt = invalid-expression "Null value during constant evaluation.";
+static const field core::bool* bazFromEnv = #C1;
+static const field core::bool* hasBazEnv = #C3;
+static const field core::int* bazFromEnvAsInt = #C7;
+static const field core::String* bazFromEnvAsString = #C8;
+static const field core::bool* bazTrueFromEnv = #C3;
+static const field core::bool* bazFalseFromEnv = #C1;
+static const field core::bool* trueBool = #C3;
+static const field core::bool* falseBool = #C1;
+static const field core::bool* binaryOnBoolCaret = #C3;
+static const field core::bool* binaryOnBoolAmpersand = #C1;
+static const field core::bool* binaryOnBoolBar = #C3;
+static const field core::bool* binaryOnBoolBar2 = #C3;
+static const field dynamic willBeDouble = #C9;
+static const field dynamic binaryOnDouble = invalid-expression "Binary operator '<<' on '42.42' requires operand of type 'int', but was of type 'double'.";
+static const field dynamic willBeInt = #C7;
+static const field dynamic binaryOnIntWithDoubleBad = invalid-expression "Binary operator '<<' on '42.42' requires operand of type 'int', but was of type 'double'.";
+static const field dynamic binaryOnIntWithDoubleOK = #C10;
+static const field dynamic binaryOnIntWithString = invalid-expression "Binary operator '<<' on '42' requires operand of type 'num', but was of type 'String'.";
+static const field dynamic willBeString = #C5;
+static const field dynamic binaryOnStringWithStringOK = #C11;
+static const field dynamic binaryOnStringWithInt = invalid-expression "Binary operator '+' on '\"hello\"' requires operand of type 'String', but was of type 'int'.";
+static const field dynamic binaryOnStringWithStringBad = invalid-expression "The method '-' can't be invoked on '\"hello\"' in a constant expression.";
+static field core::int* x = 1;
+static const field core::int* x1 = invalid-expression "Not a constant expression.";
+static const field core::int* x2 = invalid-expression "Not a constant expression.";
+static const field core::int* x3 = invalid-expression "The invocation of 'x' is not allowed in a constant expression.";
+static const field core::int* x4 = invalid-expression "The invocation of 'x' is not allowed in a constant expression.";
+static const field core::int* y = #C12;
+static const field invalid-type y1 = invalid-expression "pkg/front_end/testcases/general/constants/various.dart:82:14: Error: Setter not found: 'y'.
+const y1 = --y;
+             ^";
+static const field invalid-type y2 = invalid-expression "pkg/front_end/testcases/general/constants/various.dart:83:14: Error: Setter not found: 'y'.
+const y2 = ++y;
+             ^";
+static const field core::int* y3 = invalid-expression "pkg/front_end/testcases/general/constants/various.dart:84:12: Error: Setter not found: 'y'.
+const y3 = y--;
+           ^";
+static const field core::int* y4 = invalid-expression "pkg/front_end/testcases/general/constants/various.dart:85:12: Error: Setter not found: 'y'.
+const y4 = y++;
+           ^";
+static field self::AbstractClassWithConstructor* abstractClassWithConstructor = throw invalid-expression "pkg/front_end/testcases/general/constants/various.dart:96:11: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+Try using a constructor or factory that is 'const'.
+    const AbstractClassWithConstructor();
+          ^";
+static const field self::ExtendsFoo1* extendsFoo1 = invalid-expression "pkg/front_end/testcases/general/constants/various.dart:118:39: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+Try using a constructor or factory that is 'const'.
+const ExtendsFoo1 extendsFoo1 = const ExtendsFoo1();
+                                      ^^^^^^^^^^^";
+static const field self::ExtendsFoo2* extendsFoo2 = invalid-expression "pkg/front_end/testcases/general/constants/various.dart:121:9: Error: The superclass, 'Foo', has no unnamed constructor that takes no arguments.
+  const ExtendsFoo2();
+        ^^^^^^^^^^^";
+static const field self::Foo* foo1 = #C14;
+static const field self::Foo* foo2 = #C14;
+static const field core::bool* foosIdentical = #C3;
+static const field core::bool* foosEqual = invalid-expression "Binary operator '==' requires receiver constant 'Foo {x: 42, y: 5}' of type 'Null', 'bool', 'int', 'double', or 'String', but was of type 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/constants/various.dart'.";
+static const field core::Symbol* barFoo = #C15;
+static const field core::Symbol* barFooEqual = #C16;
+static const field core::Symbol* tripleShiftSymbol = #C17;
+static const field core::Symbol* symbolWithDots = #C18;
+static const field core::int* circularity1 = invalid-expression "Constant expression depends on itself.";
+static const field core::int* circularity2 = invalid-expression "Constant expression depends on itself.";
+static const field core::int* circularity3 = invalid-expression "Constant expression depends on itself.";
+static const field core::int* circularity4 = invalid-expression "Constant expression depends on itself.";
+static const field invalid-type function_const = invalid-expression "pkg/front_end/testcases/general/constants/various.dart:140:24: Error: Not a constant expression.
+const function_const = () {};
+                       ^^";
+static field () →* Null function_var = () → Null {};
+static field self::ConstClassWithFailingAssertWithEmptyMessage* failedAssertEmptyMessage = invalid-expression "This assertion failed with message: (empty)";
+static const field self::ClassWithTypeArguments<dynamic, dynamic, dynamic>* classWithTypeArguments1 = #C19;
+static const field self::ClassWithTypeArguments<dynamic, dynamic, dynamic>* classWithTypeArguments2 = #C20;
+static const field core::bool* classWithTypeArgumentsIdentical = #C1;
+static field self::ClassWithNonEmptyConstConstructor* classWithNonEmptyConstConstructor = invalid-expression "pkg/front_end/testcases/general/constants/various.dart:168:11: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+Try using a constructor or factory that is 'const'.
+    const ClassWithNonEmptyConstConstructor();
+          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+static field self::ConstClassWithFinalFields2* constClassWithFinalFields = invalid-expression "The invocation of 'x' is not allowed in a constant expression.";
+static const field core::bool* zeroPointZeroIdentical = #C3;
+static const field core::bool* zeroPointZeroIdenticalToZero = #C1;
+static const field core::bool* zeroIdenticalToZeroPointZero = #C1;
+static const field core::bool* nanIdentical = #C3;
+static const field core::bool* zeroPointZeroEqual = #C3;
+static const field core::bool* zeroPointZeroEqualToZero = #C3;
+static const field core::bool* zeroEqualToZeroPointZero = #C3;
+static const field core::bool* nanEqual = #C1;
+static const field dynamic willBecomeNull = #C2;
+static const field (core::int*) →* core::int* willBecomeNullToo = #C2;
+static const field (core::int*) →* core::int* partialInstantiation = #C22;
+static const field core::bool* yBool = #C3;
+static const field core::bool* zBool = #C1;
+static const field core::Object* maybeInt = #C3;
+static const field core::bool* isItInt = #C1;
+static const field core::Object* maybeInt2 = #C3;
+static const field core::bool* isItInt2 = #C1;
+static const field core::int* maybeInt3 = #C2;
+static const field core::bool* isItInt3 = #C1;
+static method id1<T extends core::Object* = dynamic>(self::id1::T* t) → self::id1::T*
+  return t;
+static method id2<T extends core::Object* = dynamic>(self::id2::T* t) → self::id2::T*
+  return t;
+static method main() → dynamic {
+  core::print(#C1);
+  core::print(#C1);
+}
+
+constants  {
+  #C1 = false
+  #C2 = null
+  #C3 = true
+  #C4 = ""
+  #C5 = "hello"
+  #C6 = 0
+  #C7 = 42
+  #C8 = "42"
+  #C9 = 42.42
+  #C10 = 84.42
+  #C11 = "hello world"
+  #C12 = 1
+  #C13 = 5
+  #C14 = self::Foo {x:#C7, y:#C13}
+  #C15 = #Foo
+  #C16 = #Foo=
+  #C17 = #>>>
+  #C18 = #I.Have.Dots
+  #C19 = self::ClassWithTypeArguments<core::int*, core::int*, core::int*> {}
+  #C20 = self::ClassWithTypeArguments<dynamic, dynamic, dynamic> {}
+  #C21 = static-tearoff self::id1
+  #C22 = instantiation #C21 <core::int*>
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///various.dart:
+- ExtendsFoo2. (from org-dartlang-testcase:///various.dart:121:9)
+- Foo. (from org-dartlang-testcase:///various.dart:109:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- ConstClassWithFailingAssertWithEmptyMessage. (from org-dartlang-testcase:///various.dart:144:9)
+- ClassWithTypeArguments. (from org-dartlang-testcase:///various.dart:151:9)
+- ConstClassWithFinalFields2. (from org-dartlang-testcase:///various.dart:177:9)
diff --git a/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart.weak.modular.expect
new file mode 100644
index 0000000..9f6cb29
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart.weak.modular.expect
@@ -0,0 +1,137 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:16:51: Error: A value of type 'int' can't be assigned to a variable of type 'bool'.
+//   const Foo.withInvalidCondition(this.x) : assert(x);
+//                                                   ^
+//
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:26:24: Error: Constant evaluation error:
+// const Foo foo2 = const Foo(0);
+//                        ^
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:8:18: Context: This assertion failed with message: x is not positive
+//       : assert(x > 0, "x is not positive"),
+//                  ^
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:26:11: Context: While analyzing:
+// const Foo foo2 = const Foo(0);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:28:24: Error: Constant evaluation error:
+// const Foo foo4 = const Foo.withInvalidMessage(42);
+//                        ^
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:15:56: Context: Expected constant '42' to be of type 'String', but was of type 'int'.
+//   const Foo.withInvalidMessage(this.x) : assert(x < 0, x);
+//                                                        ^
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:28:11: Context: While analyzing:
+// const Foo foo4 = const Foo.withInvalidMessage(42);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:30:24: Error: Constant evaluation error:
+// const Bar bar1 = const Bar.withMessage(1);
+//                        ^
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:21:44: Context: This assertion failed with message: x is not negative
+//   const Bar.withMessage(this.x) : assert(x < 0, "x is not negative");
+//                                            ^
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:30:11: Context: While analyzing:
+// const Bar bar1 = const Bar.withMessage(1);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:31:24: Error: Constant evaluation error:
+// const Bar bar2 = const Bar.withMessage(0);
+//                        ^
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:21:44: Context: This assertion failed with message: x is not negative
+//   const Bar.withMessage(this.x) : assert(x < 0, "x is not negative");
+//                                            ^
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:31:11: Context: While analyzing:
+// const Bar bar2 = const Bar.withMessage(0);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:32:24: Error: Constant evaluation error:
+// const Bar bar3 = const Bar.withoutMessage(1);
+//                        ^
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:22:47: Context: This assertion failed.
+//   const Bar.withoutMessage(this.x) : assert(x < 0);
+//                                               ^
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:32:11: Context: While analyzing:
+// const Bar bar3 = const Bar.withoutMessage(1);
+//           ^
+//
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:33:24: Error: Constant evaluation error:
+// const Bar bar4 = const Bar.withoutMessage(0);
+//                        ^
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:22:47: Context: This assertion failed.
+//   const Bar.withoutMessage(this.x) : assert(x < 0);
+//                                               ^
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:33:11: Context: While analyzing:
+// const Bar bar4 = const Bar.withoutMessage(0);
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  final field core::int x;
+  const constructor •(core::int x) → self::Foo
+    : self::Foo::x = x, assert(x.{core::num::>}(0){(core::num) → core::bool}, "x is not positive"), assert(x.{core::num::>}(0){(core::num) → core::bool}), assert(#C2 =={core::Object::==}{(core::Object) → core::bool} false, "foo was ${#C3}"), assert(#C4 =={core::Object::==}{(core::Object) → core::bool} false), super core::Object::•()
+    ;
+  const constructor withMessage(core::int x) → self::Foo
+    : self::Foo::x = x, assert(x.{core::num::<}(0){(core::num) → core::bool}, "btw foo was ${#C5}"), super core::Object::•()
+    ;
+  const constructor withInvalidMessage(core::int x) → self::Foo
+    : self::Foo::x = x, assert(x.{core::num::<}(0){(core::num) → core::bool}, x), super core::Object::•()
+    ;
+  const constructor withInvalidCondition(core::int x) → self::Foo
+    : self::Foo::x = x, assert(invalid-expression "pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:16:51: Error: A value of type 'int' can't be assigned to a variable of type 'bool'.
+  const Foo.withInvalidCondition(this.x) : assert(x);
+                                                  ^" in x as{TypeError,ForNonNullableByDefault} core::bool), super core::Object::•()
+    ;
+}
+class Bar extends core::Object /*hasConstConstructor*/  {
+  final field core::int x;
+  const constructor withMessage(core::int x) → self::Bar
+    : self::Bar::x = x, assert(x.{core::num::<}(0){(core::num) → core::bool}, "x is not negative"), super core::Object::•()
+    ;
+  const constructor withoutMessage(core::int x) → self::Bar
+    : self::Bar::x = x, assert(x.{core::num::<}(0){(core::num) → core::bool}), super core::Object::•()
+    ;
+}
+static const field self::Foo foo1 = #C9;
+static const field self::Foo foo2 = invalid-expression "This assertion failed with message: x is not positive";
+static const field self::Foo foo3 = #C12;
+static const field self::Foo foo4 = invalid-expression "Expected constant '42' to be of type 'String', but was of type 'int'.";
+static const field self::Foo foo5 = invalid-expression "pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_asserts.dart:16:51: Error: A value of type 'int' can't be assigned to a variable of type 'bool'.
+  const Foo.withInvalidCondition(this.x) : assert(x);
+                                                  ^";
+static const field self::Bar bar1 = invalid-expression "This assertion failed with message: x is not negative";
+static const field self::Bar bar2 = invalid-expression "This assertion failed with message: x is not negative";
+static const field self::Bar bar3 = invalid-expression "This assertion failed.";
+static const field self::Bar bar4 = invalid-expression "This assertion failed.";
+static method main() → dynamic {
+  core::print(#C9);
+}
+
+constants  {
+  #C1 = "foo"
+  #C2 = eval const core::bool::fromEnvironment(#C1)
+  #C3 = eval const core::bool::fromEnvironment(#C1)
+  #C4 = eval const core::bool::fromEnvironment(#C1)
+  #C5 = eval const core::bool::fromEnvironment(#C1)
+  #C6 = 1
+  #C7 = false
+  #C8 = "foo was "
+  #C9 = eval self::Foo{x:#C6, assert(const core::bool::fromEnvironment(#C1) =={core::Object::==}{(core::Object) → core::bool} #C7, "${#C8}${const core::bool::fromEnvironment(#C1)}"), assert(const core::bool::fromEnvironment(#C1) =={core::Object::==}{(core::Object) → core::bool} #C7)}
+  #C10 = 42
+  #C11 = "btw foo was "
+  #C12 = eval self::Foo{x:#C10, assert(#C7, "${#C11}${const core::bool::fromEnvironment(#C1)}")}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///const_asserts.dart:
+- Foo. (from org-dartlang-testcase:///const_asserts.dart:7:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Foo.withMessage (from org-dartlang-testcase:///const_asserts.dart:13:9)
+- Foo.withInvalidMessage (from org-dartlang-testcase:///const_asserts.dart:15:9)
+- Foo.withInvalidCondition (from org-dartlang-testcase:///const_asserts.dart:16:9)
+- Bar.withMessage (from org-dartlang-testcase:///const_asserts.dart:21:9)
+- Bar.withoutMessage (from org-dartlang-testcase:///const_asserts.dart:22:9)
diff --git a/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_collections.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_collections.dart.weak.modular.expect
new file mode 100644
index 0000000..8044a08
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_collections.dart.weak.modular.expect
@@ -0,0 +1,52 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_collections.dart:27:7: Error: Expected 2 type arguments.
+// const Map<bool> MapWithUnevaluated = {
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+static const field core::List<core::bool> listWithUnevaluated = #C5;
+static const field core::List<core::bool> listWithUnevaluatedSpread = #C8;
+static const field core::Set<core::bool> setWithUnevaluated = #C10;
+static const field core::Set<core::bool> setWithUnevaluatedSpread = #C12;
+static const field core::List<core::int> a = #C13;
+static const field core::List<core::int?> b = #C14;
+static const field core::Set<core::List<core::int?>> setNotAgnosticOK = #C15;
+static const field invalid-type MapWithUnevaluated = #C16;
+static const field core::Map<core::List<core::int?>, core::int> mapNotAgnosticOK = #C19;
+static method main() → dynamic {
+  core::print(#C5);
+  core::print(#C8);
+  core::print(#C10);
+  core::print(#C12);
+  core::print(<core::String>{"hello"});
+  core::print(#C21);
+}
+
+constants  {
+  #C1 = "foo"
+  #C2 = "bar"
+  #C3 = true
+  #C4 = <core::bool*>[#C3]
+  #C5 = eval const <dynamic>[const core::bool::fromEnvironment(#C1)] + const <dynamic>[const core::bool::fromEnvironment(#C2)] + #C4
+  #C6 = false
+  #C7 = <core::bool*>[#C6]
+  #C8 = eval #C4 + const <dynamic>[const core::bool::fromEnvironment(#C1)] + const <dynamic>[const core::bool::fromEnvironment(#C2)] + #C4 + #C7
+  #C9 = <core::bool*>{#C3}
+  #C10 = eval const <dynamic>{const core::bool::fromEnvironment(#C1)} + const <dynamic>{const core::bool::fromEnvironment(#C2)} + #C9
+  #C11 = <core::bool*>{#C6}
+  #C12 = eval #C9 + const <dynamic>{const core::bool::fromEnvironment(#C1)} + const <dynamic>{const core::bool::fromEnvironment(#C2)} + #C9 + #C11
+  #C13 = <core::int*>[]
+  #C14 = <core::int?>[]
+  #C15 = <core::List<core::int?>*>{#C13, #C14}
+  #C16 = eval const <dynamic, dynamic>{const core::bool::fromEnvironment(#C1): const core::bool::fromEnvironment(#C2)}
+  #C17 = 0
+  #C18 = 1
+  #C19 = <core::List<core::int?>*, core::int*>{#C13:#C17, #C14:#C18)
+  #C20 = "hello"
+  #C21 = <core::String*>{#C20}
+}
diff --git a/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_collections_2.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_collections_2.dart.weak.modular.expect
new file mode 100644
index 0000000..19a8cfb
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/const_collections_2.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static const field core::List<core::String> listWithUnevaluatedUnevaluatedFirst = #C6;
+static const field core::List<core::String> listWithUnevaluatedUnevaluatedMiddle = #C14;
+static const field core::Set<core::String> setWithUnevaluatedUnevaluatedFirst = #C16;
+static const field core::Set<core::String> setWithUnevaluatedUnevaluatedMiddle = #C19;
+static const field core::Map<core::String, core::int> mapWithUnevaluatedUnevaluatedFirst = #C22;
+static const field core::Map<core::String, core::int> mapWithUnevaluatedUnevaluatedMiddle = #C25;
+
+constants  {
+  #C1 = "foo"
+  #C2 = "bar"
+  #C3 = "hello"
+  #C4 = "world"
+  #C5 = <core::String*>[#C3, #C4]
+  #C6 = eval const <dynamic>[const core::String::fromEnvironment(#C1)] + const <dynamic>[const core::String::fromEnvironment(#C2)] + #C5
+  #C7 = "A"
+  #C8 = "few"
+  #C9 = "strings"
+  #C10 = <core::String*>[#C7, #C8, #C9]
+  #C11 = "and"
+  #C12 = "more"
+  #C13 = <core::String*>[#C3, #C4, #C11, #C12]
+  #C14 = eval #C10 + const <dynamic>[const core::String::fromEnvironment(#C1)] + const <dynamic>[const core::String::fromEnvironment(#C2)] + #C13
+  #C15 = <core::String*>{#C3, #C4}
+  #C16 = eval const <dynamic>{const core::String::fromEnvironment(#C1)} + #C15
+  #C17 = <core::String*>{#C7, #C8, #C9}
+  #C18 = <core::String*>{#C3, #C4, #C11, #C12}
+  #C19 = eval #C17 + const <dynamic>{const core::String::fromEnvironment(#C1)} + #C18
+  #C20 = 42
+  #C21 = <core::String*, core::int*>{#C3:#C20, #C4:#C20)
+  #C22 = eval const <dynamic, dynamic>{const core::String::fromEnvironment(#C1): #C20} + #C21
+  #C23 = <core::String*, core::int*>{#C7:#C20, #C8:#C20, #C9:#C20)
+  #C24 = <core::String*, core::int*>{#C3:#C20, #C4:#C20, #C11:#C20, #C12:#C20)
+  #C25 = eval #C23 + const <dynamic, dynamic>{const core::String::fromEnvironment(#C1): #C20} + #C24
+}
diff --git a/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/many_fields_pointing_to_previous_field.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/many_fields_pointing_to_previous_field.dart.weak.modular.expect
new file mode 100644
index 0000000..8a84689
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/many_fields_pointing_to_previous_field.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static const field core::List<core::String> original = #C11;
+static const field core::List<core::String> copy1 = #C11;
+static const field core::List<core::String> copy2 = #C11;
+static const field core::List<core::String> copy3 = #C11;
+static const field core::List<core::String> copy4 = #C11;
+static const field core::List<core::String> copy5 = #C11;
+static const field core::List<core::String> copy6 = #C11;
+static const field core::List<core::String> copy7 = #C11;
+static const field core::List<core::String> copy8 = #C11;
+static const field core::List<core::String> copy9 = #C11;
+static const field core::List<core::String> copy10 = #C11;
+static const field core::List<core::String> copy11 = #C11;
+static const field core::List<core::String> copy12 = #C11;
+static const field core::List<core::String> copy13 = #C11;
+static const field core::List<core::String> copy14 = #C11;
+static const field core::List<core::String> copy15 = #C11;
+static const field core::List<core::String> copy16 = #C11;
+static const field core::List<core::String> copy17 = #C11;
+static const field core::List<core::String> copy18 = #C11;
+static const field core::List<core::String> copy19 = #C11;
+static const field core::List<core::String> copy20 = #C11;
+static const field core::List<core::String> copy21 = #C11;
+static const field core::List<core::String> copy22 = #C11;
+static const field core::List<core::String> copy23 = #C11;
+static const field core::List<core::String> copy24 = #C11;
+static const field core::List<core::String> copy25 = #C11;
+static const field core::List<core::String> copy26 = #C11;
+static const field core::List<core::String> copy27 = #C11;
+static const field core::List<core::String> copy28 = #C11;
+static const field core::List<core::String> copy29 = #C11;
+static const field core::List<core::String> copy30 = #C11;
+static const field core::List<core::String> copy31 = #C11;
+static const field core::List<core::String> copy32 = #C11;
+static const field core::List<core::String> copy33 = #C11;
+static const field core::List<core::String> copy34 = #C11;
+static const field core::List<core::String> copy35 = #C11;
+static const field core::List<core::String> copy36 = #C11;
+static const field core::List<core::String> copy37 = #C11;
+static const field core::List<core::String> copy38 = #C11;
+static const field core::List<core::String> copy39 = #C11;
+static const field core::List<core::String> copy40 = #C11;
+static const field core::List<core::String> copy41 = #C11;
+static const field core::List<core::String> copy42 = #C11;
+static const field core::List<core::String> copy43 = #C11;
+static const field core::List<core::String> copy44 = #C11;
+static const field core::List<core::String> copy45 = #C11;
+static const field core::List<core::String> copy46 = #C11;
+static const field core::List<core::String> copy47 = #C11;
+static const field core::List<core::String> copy48 = #C11;
+static const field core::List<core::String> copy49 = #C11;
+static const field core::List<core::String> copy50 = #C11;
+
+constants  {
+  #C1 = "lots"
+  #C2 = "of"
+  #C3 = "strings"
+  #C4 = <core::String*>[#C1, #C2, #C3]
+  #C5 = "original"
+  #C6 = "that"
+  #C7 = "are"
+  #C8 = "already"
+  #C9 = "constants"
+  #C10 = <core::String*>[#C6, #C7, #C8, #C9]
+  #C11 = eval #C4 + const <dynamic>[const core::String::fromEnvironment(#C5)] + #C10
+}
diff --git a/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/rudimentary_test_01.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/rudimentary_test_01.dart.weak.modular.expect
new file mode 100644
index 0000000..9505b07
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/rudimentary_test_01.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static const field core::int foo = #C1;
+static const field core::String bar = #C6;
+static const field core::bool baz = #C7;
+static const field core::Symbol blaSymbol = #C8;
+static method main() → dynamic {
+  self::_x();
+  #C10;
+  core::print(#C6);
+}
+static method _x() → void {
+  core::print(#C1);
+  core::print(#C6);
+}
+
+constants  {
+  #C1 = 1764
+  #C2 = "hello "
+  #C3 = "baz"
+  #C4 = "world"
+  #C5 = "!"
+  #C6 = eval "${#C2}${const core::String::fromEnvironment(#C3, defaultValue: #C4)}${#C5}"
+  #C7 = true
+  #C8 = #org-dartlang-testcase:///rudimentary_test_01.dart::_x
+  #C9 = "foo"
+  #C10 = eval const core::bool::fromEnvironment(#C9)
+}
diff --git a/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart.weak.modular.expect
new file mode 100644
index 0000000..d340989
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart.weak.modular.expect
@@ -0,0 +1,255 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart:27:3: Error: Only static fields can be declared as const.
+// Try using 'final' instead of 'const', or adding the keyword 'static'.
+//   const bool initialized =
+//   ^^^^^
+//
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart:22:25: Error: 'lib' can't be used in a constant expression because it's marked as 'deferred' which means it isn't available until loaded.
+// Try moving the constant from the deferred library, or removing 'deferred' from the import.
+//
+// const fromDeferredLib = lib.x;
+//                         ^^^
+//
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart:14:30: Warning: Operand of null-aware operation '??' has type 'bool' which excludes null.
+// const bool nullAwareOnNull = barFromEnvOrNull ?? true;
+//                              ^
+//
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart:100:34: Error: The argument type 'A' can't be assigned to the parameter type 'T'.
+//  - 'A' is from 'pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart'.
+//   const Class.method(T t) : this(-t);
+//                                  ^
+//
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart:123:27: Error: The parameter 'named' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// int procedure(int i, {int named}) => i;
+//                           ^^^^^
+//
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart:31:9: Error: Constructor is marked 'const' so all fields must be final.
+//   const Foo(this.value,
+//         ^
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart:27:14: Context: Field isn't final, but constructor is 'const'.
+//   const bool initialized =
+//              ^
+//
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart:22:29: Error: Constant evaluation error:
+// const fromDeferredLib = lib.x;
+//                             ^
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart:22:29: Context: 'lib' can't be used in a constant expression because it's marked as 'deferred' which means it isn't available until loaded.
+// Try moving the constant from the deferred library, or removing 'deferred' from the import.
+//
+// const fromDeferredLib = lib.x;
+//                             ^
+// pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart:22:7: Context: While analyzing:
+// const fromDeferredLib = lib.x;
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+import "org-dartlang-testcase:///various_lib.dart" deferred as lib;
+
+typedef F = (core::int, {named: core::int}) → core::int;
+class Foo<E extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field core::bool saved;
+  final field core::bool saved2;
+  field core::bool initialized = #C3;
+  final field self::Foo::E% value;
+  const constructor •(self::Foo::E% value, {core::bool saved2 = #C4, core::bool x = #C5}) → self::Foo<self::Foo::E%>
+    : self::Foo::value = value, self::Foo::saved2 = saved2, self::Foo::saved = x, super core::Object::•()
+    ;
+}
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A
+    : super core::Object::•()
+    ;
+  operator unary-() → self::A
+    return this;
+}
+class B extends core::Object implements self::A /*hasConstConstructor*/  {
+  const constructor •() → self::B
+    : super core::Object::•()
+    ;
+  operator unary-() → self::B
+    return this;
+}
+class C extends core::Object implements self::A /*hasConstConstructor*/  {
+  const constructor •() → self::C
+    : super core::Object::•()
+    ;
+  operator unary-() → self::C
+    return this;
+}
+class Class<T extends self::A> extends core::Object /*hasConstConstructor*/  {
+  const constructor •(self::Class::T t) → self::Class<self::Class::T>
+    : super core::Object::•()
+    ;
+  const constructor redirect(dynamic t) → self::Class<self::Class::T>
+    : this self::Class::•(t as{TypeError,ForDynamic,ForNonNullableByDefault} self::Class::T)
+    ;
+  const constructor method(self::Class::T t) → self::Class<self::Class::T>
+    : this self::Class::•(invalid-expression "pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart:100:34: Error: The argument type 'A' can't be assigned to the parameter type 'T'.
+ - 'A' is from 'pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart'.
+  const Class.method(T t) : this(-t);
+                                 ^" in t.{self::A::unary-}(){() → self::A} as{TypeError,ForNonNullableByDefault} Never)
+    ;
+}
+class Subclass<T extends self::A> extends self::Class<self::Subclass::T> /*hasConstConstructor*/  {
+  const constructor •(dynamic t) → self::Subclass<self::Subclass::T>
+    : super self::Class::•(t as{TypeError,ForDynamic,ForNonNullableByDefault} self::Subclass::T)
+    ;
+}
+class ConstClassWithF extends core::Object /*hasConstConstructor*/  {
+  final field (core::int, {named: core::int}) → core::int foo;
+  const constructor •((core::int, {named: core::int}) → core::int foo) → self::ConstClassWithF
+    : self::ConstClassWithF::foo = foo, super core::Object::•()
+    ;
+}
+static const field core::bool barFromEnv = #C6;
+static const field core::bool hasBarEnv = #C7;
+static const field core::bool? barFromEnvOrNull0 = #C10;
+static const field core::bool barFromEnvOrNull = #C11;
+static const field core::bool notBarFromEnvOrNull = #C12;
+static const field core::bool conditionalOnNull = #C14;
+static const field core::bool nullAwareOnNull = #C15;
+static const field core::bool andOnNull = #C16;
+static const field core::bool andOnNull2 = #C11;
+static const field core::bool orOnNull = #C17;
+static const field core::bool orOnNull2 = #C18;
+static const field core::bool orOnNull3 = #C8;
+static const field core::bool orOnNull4 = #C11;
+static const field core::int fromDeferredLib = invalid-expression "'lib' can't be used in a constant expression because it's marked as 'deferred' which means it isn't available until loaded.";
+static const field self::Foo<core::int> x = #C20;
+static const field core::bool? y = #C8;
+static const field core::bool z = #C13;
+static const field core::Object maybeInt = #C21;
+static const field core::bool isItInt = #C22;
+static const field core::Object maybeInt2 = #C8;
+static const field core::bool isItInt2 = #C13;
+static const field core::int? maybeInt3 = #C9;
+static const field core::bool isItInt3 = #C13;
+static const field dynamic listOfNull = #C23;
+static const field core::bool isListOfNull = #C8;
+static const field dynamic listOfInt = #C24;
+static const field core::bool isListOfInt = #C8;
+static const field core::bool isList = #C8;
+static const field dynamic setOfInt = #C25;
+static const field core::bool isSetOfInt = #C8;
+static const field dynamic mapOfInt = #C26;
+static const field core::bool isMapOfInt = #C8;
+static const field dynamic listOfListOfInt = #C27;
+static const field core::bool isListOfListOfInt = #C8;
+static const field dynamic setOfSetOfInt = #C28;
+static const field core::bool isSetOfSetOfInt = #C8;
+static const field dynamic mapOfMapOfInt1 = #C29;
+static const field dynamic mapOfMapOfInt2 = #C30;
+static const field core::bool isMapOfMapOfInt1 = #C8;
+static const field core::bool isMapOfMapOfInt2 = #C8;
+static const field core::Symbol symbolWithUnevaluatedParameter = #C31;
+static const field core::Symbol symbolWithInvalidName = #C32;
+static const field self::Class<self::B>? c0 = #C34;
+static const field self::Class<self::A>? c1 = invalid-expression "pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart:100:34: Error: The argument type 'A' can't be assigned to the parameter type 'T'.
+ - 'A' is from 'pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart'.
+  const Class.method(T t) : this(-t);
+                                 ^";
+static const field self::Subclass<self::B>? c2 = #C35;
+static const field self::Class<self::A>? c3 = #C36;
+static const field self::Class<self::B>? c4 = #C37;
+static const field self::Subclass<self::A>? c5 = #C38;
+static const field self::Subclass<self::B>? c6 = #C39;
+static const field core::Type f = #C40;
+static field self::ConstClassWithF constClassWithF1 = #C42;
+static const field self::ConstClassWithF constClassWithF2 = #C42;
+static const field core::bool unevaluatedBool = #C43;
+static const field core::bool notUnevaluatedBool = #C44;
+static const field core::bool? unevaluatedBoolOrNull = #C45;
+static const field core::bool unevaluatedBoolNotNull = #C46;
+static method procedure(core::int i, {core::int named = #C9}) → core::int
+  return i;
+static method main() → dynamic {
+  core::print(#C34);
+  core::print(invalid-expression "pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart:100:34: Error: The argument type 'A' can't be assigned to the parameter type 'T'.
+ - 'A' is from 'pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various.dart'.
+  const Class.method(T t) : this(-t);
+                                 ^");
+  core::print(#C35);
+  core::print(#C36);
+  core::print(#C37);
+  core::print(#C38);
+  core::print(#C39);
+  core::print(#C20);
+  core::print(#C20.{self::Foo::saved}{core::bool});
+  core::print(#C20.{self::Foo::value}{core::int});
+}
+
+library /*isNonNullableByDefault*/;
+import self as self2;
+import "dart:core" as core;
+
+static const field core::int x = #C19;
+
+constants  {
+  #C1 = "foo"
+  #C2 = "bar"
+  #C3 = eval const core::bool::fromEnvironment(#C1, defaultValue: const core::bool::fromEnvironment(#C2))
+  #C4 = eval const core::bool::fromEnvironment(#C1, defaultValue: const core::bool::fromEnvironment(#C2))
+  #C5 = eval const core::bool::fromEnvironment(#C1, defaultValue: const core::bool::fromEnvironment(#C2))
+  #C6 = eval const core::bool::fromEnvironment(#C2)
+  #C7 = eval const core::bool::hasEnvironment(#C2)
+  #C8 = true
+  #C9 = null
+  #C10 = eval const core::bool::fromEnvironment(#C2) ?{core::bool?} #C8 : #C9
+  #C11 = eval const core::bool::fromEnvironment(#C2, defaultValue: (const core::bool::fromEnvironment(#C2) ?{core::bool?} #C8 : #C9)!)
+  #C12 = eval !const core::bool::fromEnvironment(#C2, defaultValue: (const core::bool::fromEnvironment(#C2) ?{core::bool?} #C8 : #C9)!)
+  #C13 = false
+  #C14 = eval const core::bool::fromEnvironment(#C2, defaultValue: (const core::bool::fromEnvironment(#C2) ?{core::bool?} #C8 : #C9)!) ?{core::bool} #C8 : #C13
+  #C15 = eval const core::bool::fromEnvironment(#C2, defaultValue: (const core::bool::fromEnvironment(#C2) ?{core::bool?} #C8 : #C9)!) == null ?{core::bool} #C8 : const core::bool::fromEnvironment(#C2, defaultValue: (const core::bool::fromEnvironment(#C2) ?{core::bool?} #C8 : #C9)!)
+  #C16 = eval const core::bool::fromEnvironment(#C2, defaultValue: (const core::bool::fromEnvironment(#C2) ?{core::bool?} #C8 : #C9)!) && #C8
+  #C17 = eval const core::bool::fromEnvironment(#C2, defaultValue: (const core::bool::fromEnvironment(#C2) ?{core::bool?} #C8 : #C9)!) || #C8
+  #C18 = eval const core::bool::fromEnvironment(#C2, defaultValue: (const core::bool::fromEnvironment(#C2) ?{core::bool?} #C8 : #C9)!) || #C13
+  #C19 = 42
+  #C20 = eval self::Foo<core::int*>{saved:const core::bool::fromEnvironment(#C1, defaultValue: const core::bool::fromEnvironment(#C2)), saved2:const core::bool::fromEnvironment(#C1, defaultValue: const core::bool::fromEnvironment(#C2)), initialized:const core::bool::fromEnvironment(#C1, defaultValue: const core::bool::fromEnvironment(#C2)), value:#C19}
+  #C21 = eval const core::bool::fromEnvironment(#C1) ?{core::Object} #C19 : #C8
+  #C22 = eval (const core::bool::fromEnvironment(#C1) ?{core::Object} #C19 : #C8) is{ForNonNullableByDefault} core::int ?{core::bool} #C8 : #C13
+  #C23 = <Null>[#C9]
+  #C24 = <core::int*>[#C19]
+  #C25 = <core::int*>{#C19}
+  #C26 = <core::int*, core::int*>{#C19:#C19)
+  #C27 = <core::List<core::int*>*>[#C24]
+  #C28 = <core::Set<core::int*>*>{#C25}
+  #C29 = <core::Map<core::int*, core::int*>*, core::int*>{#C26:#C19)
+  #C30 = <core::int*, core::Map<core::int*, core::int*>*>{#C19:#C26)
+  #C31 = eval const _in::Symbol::•(const core::String::fromEnvironment(#C1))
+  #C32 = #42
+  #C33 = "x"
+  #C34 = eval const core::bool::fromEnvironment(#C33) ?{self::Class<self::B>?} #C9 : self::Class<self::B*>{(self::C{}) as{ForNonNullableByDefault} self::B*}
+  #C35 = eval const core::bool::fromEnvironment(#C33) ?{self::Subclass<self::B>?} #C9 : self::Subclass<self::B*>{(self::C{}) as{ForNonNullableByDefault} self::B*}
+  #C36 = eval const core::bool::fromEnvironment(#C33) ?{self::Class<self::A>?} #C9 : self::Class<self::A*>{self::A{}}
+  #C37 = eval const core::bool::fromEnvironment(#C33) ?{self::Class<self::B>?} #C9 : self::Class<self::B*>{(self::B{}) as{ForNonNullableByDefault} self::B*}
+  #C38 = eval const core::bool::fromEnvironment(#C33) ?{self::Subclass<self::A>?} #C9 : self::Subclass<self::A*>{(self::A{}) as{ForNonNullableByDefault} self::A*}
+  #C39 = eval const core::bool::fromEnvironment(#C33) ?{self::Subclass<self::B>?} #C9 : self::Subclass<self::B*>{(self::B{}) as{ForNonNullableByDefault} self::B*}
+  #C40 = TypeLiteralConstant((core::int*, {named: core::int*}) →* core::int*)
+  #C41 = static-tearoff self::procedure
+  #C42 = self::ConstClassWithF {foo:#C41}
+  #C43 = eval const core::bool::fromEnvironment(#C1)
+  #C44 = eval !const core::bool::fromEnvironment(#C1)
+  #C45 = eval const core::bool::fromEnvironment(#C2) ?{core::bool?} const core::bool::fromEnvironment(#C1) : #C9
+  #C46 = eval (const core::bool::fromEnvironment(#C2) ?{core::bool?} const core::bool::fromEnvironment(#C1) : #C9)!
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///various.dart:
+- C. (from org-dartlang-testcase:///various.dart:92:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Class.redirect (from org-dartlang-testcase:///various.dart:99:9)
+- Class. (from org-dartlang-testcase:///various.dart:98:9)
+- A. (from org-dartlang-testcase:///various.dart:80:9)
+- Class.method (from org-dartlang-testcase:///various.dart:100:9)
+- Subclass. (from org-dartlang-testcase:///various.dart:104:9)
+- B. (from org-dartlang-testcase:///various.dart:86:9)
+- Foo. (from org-dartlang-testcase:///various.dart:31:9)
+- ConstClassWithF. (from org-dartlang-testcase:///various.dart:120:9)
diff --git a/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various_2.dart.weak.modular.expect b/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various_2.dart.weak.modular.expect
new file mode 100644
index 0000000..d4686ed
--- /dev/null
+++ b/pkg/front_end/testcases/general/constants/with_unevaluated_agnostic/various_2.dart.weak.modular.expect
@@ -0,0 +1,138 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "various_2_lib.dart" as var;
+
+import "org-dartlang-testcase:///various_2_lib.dart" as lib;
+
+typedef F1<invariant T extends core::Object? = dynamic> = (T%) → T%;
+typedef F2 = <T extends core::Object? = dynamic>(T%) → T%;
+static const field core::Type objectTypeLiteral = #C1;
+static const field (core::int) → core::int partialInstantiation = #C3;
+static const field var::Class<core::int> instance = #C5;
+static const field var::Class<dynamic> instance2 = #C8;
+static const field core::Type functionTypeLiteral = #C9;
+static const field core::Type genericFunctionTypeLiteral = #C10;
+static const field core::List<core::int> listLiteral = #C11;
+static const field core::List<dynamic> listLiteral2 = #C12;
+static const field core::Set<core::int> setLiteral = #C13;
+static const field core::Set<dynamic> setLiteral2 = #C14;
+static const field core::Map<core::int, core::String> mapLiteral = #C16;
+static const field core::Map<dynamic, dynamic> mapLiteral2 = #C18;
+static const field core::List<core::int> listConcatenation = #C11;
+static const field core::Set<core::int> setConcatenation = #C13;
+static const field core::Map<core::int, core::String> mapConcatenation = #C16;
+static const field core::bool objectTypeLiteralIdentical = #C19;
+static const field core::bool partialInstantiationIdentical = #C21;
+static const field core::bool instanceIdentical = #C19;
+static const field core::bool instance2Identical = #C19;
+static const field core::bool functionTypeLiteralIdentical = #C19;
+static const field core::bool genericFunctionTypeLiteralIdentical = #C19;
+static const field core::bool listLiteralIdentical = #C19;
+static const field core::bool listLiteral2Identical = #C19;
+static const field core::bool setLiteralIdentical = #C19;
+static const field core::bool setLiteral2Identical = #C19;
+static const field core::bool mapLiteralIdentical = #C19;
+static const field core::bool mapLiteral2Identical = #C19;
+static const field core::bool listConcatenationIdentical = #C19;
+static const field core::bool setConcatenationIdentical = #C19;
+static const field core::bool mapConcatenationIdentical = #C19;
+static method main() → dynamic {
+  self::test(#C1, #C1);
+  self::test(#C3, #C22);
+  self::test(#C5, #C5);
+  self::test(#C9, #C9);
+  self::test(#C10, #C10);
+  self::test(#C11, #C11);
+  self::test(#C13, #C13);
+  self::test(#C16, #C16);
+  self::test(#C11, #C11);
+  self::test(#C13, #C13);
+  self::test(#C16, #C16);
+  self::test(true, #C19);
+  self::test(true, #C21);
+  self::test(true, #C19);
+  self::test(true, #C19);
+  self::test(true, #C19);
+  self::test(true, #C19);
+  self::test(true, #C19);
+  self::test(true, #C19);
+  self::test(true, #C19);
+  self::test(true, #C19);
+  self::test(true, #C19);
+}
+static method test(dynamic expected, dynamic actual) → dynamic {
+  core::print("test(${expected}, ${actual})");
+  if(!core::identical(expected, actual)) {
+    throw "Expected ${expected}, actual ${actual}";
+  }
+}
+
+library /*isNonNullableByDefault*/;
+import self as var;
+import "dart:core" as core;
+
+typedef F1<invariant T extends core::Object? = dynamic> = (T%) → T%;
+typedef F2 = <T extends core::Object? = dynamic>(T%) → T%;
+class Class<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field var::Class::T% field;
+  const constructor •(var::Class::T% field) → var::Class<var::Class::T%>
+    : var::Class::field = field, super core::Object::•()
+    ;
+}
+static const field core::Type objectTypeLiteral = #C1;
+static const field (core::Object?, core::Object?) → core::bool c2 = #C23;
+static const field (core::int) → core::int partialInstantiation = #C22;
+static const field var::Class<core::int> instance = #C5;
+static const field var::Class<dynamic> instance2 = #C8;
+static const field core::Type functionTypeLiteral = #C9;
+static const field core::Type genericFunctionTypeLiteral = #C10;
+static const field core::List<core::int> listLiteral = #C11;
+static const field core::List<dynamic> listLiteral2 = #C12;
+static const field core::Set<core::int> setLiteral = #C13;
+static const field core::Set<dynamic> setLiteral2 = #C14;
+static const field core::Map<core::int, core::String> mapLiteral = #C16;
+static const field core::Map<dynamic, dynamic> mapLiteral2 = #C18;
+static const field core::List<core::int> listConcatenation = #C11;
+static const field core::Set<core::int> setConcatenation = #C13;
+static const field core::Map<core::int, core::String> mapConcatenation = #C16;
+static method id1<T extends core::Object? = dynamic>(var::id1::T% t) → var::id1::T%
+  return t;
+static method id2<T extends core::Object? = dynamic>(var::id2::T% t) → var::id2::T%
+  return t;
+
+constants  {
+  #C1 = TypeLiteralConstant(core::Object*)
+  #C2 = static-tearoff var::id1
+  #C3 = instantiation #C2 <core::int*>
+  #C4 = 0
+  #C5 = var::Class<core::int*> {field:#C4}
+  #C6 = 42
+  #C7 = <core::int*>[#C6]
+  #C8 = var::Class<dynamic> {field:#C7}
+  #C9 = TypeLiteralConstant((dynamic) →* dynamic)
+  #C10 = TypeLiteralConstant(<T extends core::Object? = dynamic>(T*) →* T*)
+  #C11 = <core::int*>[#C4]
+  #C12 = <dynamic>[#C7]
+  #C13 = <core::int*>{#C4}
+  #C14 = <dynamic>{#C7}
+  #C15 = "foo"
+  #C16 = <core::int*, core::String*>{#C4:#C15)
+  #C17 = null
+  #C18 = <dynamic, dynamic>{#C7:#C15, #C17:#C7)
+  #C19 = true
+  #C20 = static-tearoff var::id2
+  #C21 = eval const core::identical(#C3, const core::bool::fromEnvironment(#C15) ?{(core::int) → core::int} #C2<core::int> : #C20<core::int>)
+  #C22 = eval const core::bool::fromEnvironment(#C15) ?{(core::int) → core::int} #C2<core::int> : #C20<core::int>
+  #C23 = static-tearoff core::identical
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///various_2.dart:
+- Class. (from org-dartlang-testcase:///various_2_lib.dart:8:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+
+org-dartlang-testcase:///various_2_lib.dart:
+- Class. (from org-dartlang-testcase:///various_2_lib.dart:8:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/constructor_const_inference.dart.weak.modular.expect b/pkg/front_end/testcases/general/constructor_const_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..2c1402b
--- /dev/null
+++ b/pkg/front_end/testcases/general/constructor_const_inference.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class _Y<T extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::_Y<self::_Y::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::_Y<self::A::T*>* x;
+  constructor •(self::_Y<self::A::T*>* x) → self::A<self::A::T*>*
+    : self::A::x = x, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::Object* = dynamic> extends self::A<self::B::T*> {
+  constructor •() → self::B<self::B::T*>*
+    : super self::A::•(#C1)
+    ;
+}
+static method main() → dynamic {
+  dynamic x = new self::B::•<dynamic>().{self::A::x}{self::_Y<dynamic>*};
+  if(!(x is self::_Y<Null>*)) {
+    throw "Unexpected run-time type: `new B().x` is ${x.{core::Object::runtimeType}{core::Type*}}, but `_Y<Null>` expected";
+  }
+}
+
+constants  {
+  #C1 = self::_Y<Null> {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///constructor_const_inference.dart:
+- _Y. (from org-dartlang-testcase:///constructor_const_inference.dart:10:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/constructor_cycle.dart.weak.modular.expect b/pkg/front_end/testcases/general/constructor_cycle.dart.weak.modular.expect
new file mode 100644
index 0000000..7510955
--- /dev/null
+++ b/pkg/front_end/testcases/general/constructor_cycle.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constructor_cycle.dart:7:18: Error: Redirecting constructors can't be cyclic.
+// Try to have all constructors eventually redirect to a non-redirecting constructor.
+//   A.bar() : this.foo();
+//                  ^^^
+//
+// pkg/front_end/testcases/general/constructor_cycle.dart:9:9: Error: Redirecting constructors can't be cyclic.
+// Try to have all constructors eventually redirect to a non-redirecting constructor.
+//   A() : this();
+//         ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  constructor foo() → self::A*
+    : this self::A::bar()
+    ;
+  constructor bar() → self::A*
+    : this self::A::foo()
+    ;
+  constructor baz() → self::A*
+    : this self::A::foo()
+    ;
+  constructor •() → self::A*
+    : this self::A::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/constructor_function_types.dart.weak.modular.expect b/pkg/front_end/testcases/general/constructor_function_types.dart.weak.modular.expect
new file mode 100644
index 0000000..3e5a359
--- /dev/null
+++ b/pkg/front_end/testcases/general/constructor_function_types.dart.weak.modular.expect
@@ -0,0 +1,70 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  constructor •(core::int* x, core::double* y, core::String* s) → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<T extends core::Object* = dynamic> extends core::Object {
+  constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<T extends core::Object* = dynamic, S extends core::Object* = dynamic> extends core::Object {
+  constructor •(self::D::T* x, self::D::S* y) → self::D<self::D::T*, self::D::S*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {
+  new self::A::•();
+  new self::B::•(0, 3.14, "foo");
+  new self::C::•<dynamic>();
+  new self::D::•<core::Object*, core::int*>(null, 3);
+}
diff --git a/pkg/front_end/testcases/general/constructor_initializer_invalid.dart.weak.modular.expect b/pkg/front_end/testcases/general/constructor_initializer_invalid.dart.weak.modular.expect
new file mode 100644
index 0000000..69f8ec9
--- /dev/null
+++ b/pkg/front_end/testcases/general/constructor_initializer_invalid.dart.weak.modular.expect
@@ -0,0 +1,87 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/constructor_initializer_invalid.dart:5:24: Error: Expected an initializer.
+// class C1 { int f; C1() : ; }
+//                        ^
+//
+// pkg/front_end/testcases/general/constructor_initializer_invalid.dart:6:26: Error: Expected an assignment after the field name.
+// To initialize a field, use the syntax 'name = value'.
+// class C2 { int f; C2() : f; }
+//                          ^
+//
+// pkg/front_end/testcases/general/constructor_initializer_invalid.dart:7:26: Error: Expected an assignment after the field name.
+// To initialize a field, use the syntax 'name = value'.
+// class C3 { int f; C3() : f++; }
+//                          ^
+//
+// pkg/front_end/testcases/general/constructor_initializer_invalid.dart:7:26: Error: Can't access 'this' in a field initializer to read 'f'.
+// class C3 { int f; C3() : f++; }
+//                          ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C1 extends core::Object {
+  field core::int* f = null;
+  constructor •() → self::C1*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/constructor_initializer_invalid.dart:5:26: Error: This couldn't be parsed.
+class C1 { int f; C1() : ; }
+                         ^"
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C2 extends core::Object {
+  field core::int* f;
+  constructor •() → self::C2*
+    : self::C2::f = invalid-expression "pkg/front_end/testcases/general/constructor_initializer_invalid.dart:6:27: Error: This couldn't be parsed.
+class C2 { int f; C2() : f; }
+                          ^", super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C3 extends core::Object {
+  field core::int* f = null;
+  constructor •() → self::C3*
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/general/constructor_initializer_invalid.dart:7:26: Error: This couldn't be parsed.
+class C3 { int f; C3() : f++; }
+                         ^"
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C1* c1 = new self::C1::•();
+  c1.{self::C1::toString}(){() →* core::String*};
+  self::C2* c2 = new self::C2::•();
+  c2.{self::C2::toString}(){() →* core::String*};
+  self::C3* c3 = new self::C3::•();
+  c3.{self::C3::toString}(){() →* core::String*};
+}
diff --git a/pkg/front_end/testcases/general/constructor_patch/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/constructor_patch/main.dart.weak.modular.expect
new file mode 100644
index 0000000..40f37f3
--- /dev/null
+++ b/pkg/front_end/testcases/general/constructor_patch/main.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:test" as test;
+
+import "dart:test";
+
+static method main() → dynamic {
+  new test::Class::generative();
+  #C2;
+}
+
+library /*isNonNullableByDefault*/;
+import self as test;
+import "dart:_internal" as _in;
+import "dart:core" as core;
+
+import "dart:_internal";
+
+@#C3
+class Class extends core::Object /*hasConstConstructor*/  {
+  final field core::bool defaultValue /* from org-dartlang-testcase:///patch_lib.dart */;
+  @#C3
+  constructor generative({core::bool defaultValue = #C1}) → test::Class
+    : test::Class::defaultValue = defaultValue, super core::Object::•()
+    ;
+  @#C3
+  const constructor constGenerative({core::bool defaultValue = #C1}) → test::Class
+    : test::Class::defaultValue = defaultValue, super core::Object::•()
+    ;
+}
+
+constants  {
+  #C1 = true
+  #C2 = test::Class {defaultValue:#C1}
+  #C3 = _in::_Patch {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///main.dart:
+- Class.constGenerative (from org-dartlang-testcase:///patch_lib.dart:16:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/constructor_patch/main.dart.weak.outline.expect b/pkg/front_end/testcases/general/constructor_patch/main.dart.weak.outline.expect
index d5e5658..ef6d09e 100644
--- a/pkg/front_end/testcases/general/constructor_patch/main.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/general/constructor_patch/main.dart.weak.outline.expect
@@ -17,7 +17,7 @@
 class Class extends core::Object /*hasConstConstructor*/  {
   final field core::bool defaultValue /* from org-dartlang-testcase:///patch_lib.dart */;
   @_in::patch
-  external constructor generative({core::bool defaultValue}) → self2::Class
+  external constructor generative({core::bool defaultValue = true}) → self2::Class
     ;
   @_in::patch
   const constructor constGenerative({core::bool defaultValue = true}) → self2::Class
diff --git a/pkg/front_end/testcases/general/continue_inference_after_error.dart.weak.modular.expect b/pkg/front_end/testcases/general/continue_inference_after_error.dart.weak.modular.expect
new file mode 100644
index 0000000..cbaacd1
--- /dev/null
+++ b/pkg/front_end/testcases/general/continue_inference_after_error.dart.weak.modular.expect
@@ -0,0 +1,47 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/continue_inference_after_error.dart:10:3: Error: A prefix can't be used as an expression.
+//   lib(new C().missing());
+//   ^^^
+//
+// pkg/front_end/testcases/general/continue_inference_after_error.dart:10:15: Error: The method 'missing' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/general/continue_inference_after_error.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'missing'.
+//   lib(new C().missing());
+//               ^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///continue_inference_after_error_lib.dart" as lib;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/continue_inference_after_error.dart:10:3: Error: A prefix can't be used as an expression.
+  lib(new C().missing());
+  ^^^" in let final core::Object* #t1 = invalid-expression "pkg/front_end/testcases/general/continue_inference_after_error.dart:10:15: Error: The method 'missing' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/general/continue_inference_after_error.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'missing'.
+  lib(new C().missing());
+              ^^^^^^^" in new self::C::•(){<unresolved>}.missing() in null;
+}
+static method main() → dynamic {}
+
+library;
+import self as self2;
diff --git a/pkg/front_end/testcases/general/control_flow_collection.dart.weak.modular.expect b/pkg/front_end/testcases/general/control_flow_collection.dart.weak.modular.expect
new file mode 100644
index 0000000..ca02ce0
--- /dev/null
+++ b/pkg/front_end/testcases/general/control_flow_collection.dart.weak.modular.expect
@@ -0,0 +1,71 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+static method main() → dynamic {
+  final core::List<core::int*>* aList = block {
+    final core::List<core::int*>* #t1 = <core::int*>[1];
+    if(self::oracle() as{TypeError,ForDynamic} core::bool*)
+      #t1.{core::List::add}{Invariant}(2){(core::int*) →* void};
+    if(self::oracle() as{TypeError,ForDynamic} core::bool*)
+      #t1.{core::List::add}{Invariant}(3){(core::int*) →* void};
+    else
+      #t1.{core::List::add}{Invariant}(1.{core::int::unary-}(){() →* core::int*}){(core::int*) →* void};
+    if(self::oracle() as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle() as{TypeError,ForDynamic} core::bool*)
+        #t1.{core::List::add}{Invariant}(4){(core::int*) →* void};
+    for (core::int* i in <core::int*>[5, 6, 7])
+      #t1.{core::List::add}{Invariant}(i){(core::int*) →* void};
+    for (core::int* i in <core::int*>[8, 9, 10])
+      if(self::oracle() as{TypeError,ForDynamic} core::bool*)
+        #t1.{core::List::add}{Invariant}(i){(core::int*) →* void};
+    for (core::int* i = 11; i.{core::num::<=}(14){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t1.{core::List::add}{Invariant}(i){(core::int*) →* void};
+  } =>#t1;
+  final core::Set<core::int*>* aSet = block {
+    final core::Set<core::int*>* #t2 = col::LinkedHashSet::•<core::int*>();
+    #t2.{core::Set::add}{Invariant}(1){(core::int*) →* core::bool*};
+    if(self::oracle() as{TypeError,ForDynamic} core::bool*)
+      #t2.{core::Set::add}{Invariant}(2){(core::int*) →* core::bool*};
+    if(self::oracle() as{TypeError,ForDynamic} core::bool*)
+      #t2.{core::Set::add}{Invariant}(3){(core::int*) →* core::bool*};
+    else
+      #t2.{core::Set::add}{Invariant}(1.{core::int::unary-}(){() →* core::int*}){(core::int*) →* core::bool*};
+    if(self::oracle() as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle() as{TypeError,ForDynamic} core::bool*)
+        #t2.{core::Set::add}{Invariant}(4){(core::int*) →* core::bool*};
+    for (core::int* i in <core::int*>[5, 6, 7])
+      #t2.{core::Set::add}{Invariant}(i){(core::int*) →* core::bool*};
+    for (core::int* i in <core::int*>[8, 9, 10])
+      if(self::oracle() as{TypeError,ForDynamic} core::bool*)
+        #t2.{core::Set::add}{Invariant}(i){(core::int*) →* core::bool*};
+    for (core::int* i = 11; i.{core::num::<=}(14){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t2.{core::Set::add}{Invariant}(i){(core::int*) →* core::bool*};
+  } =>#t2;
+  final core::Map<core::int*, core::int*>* aMap = block {
+    final core::Map<core::int*, core::int*>* #t3 = <core::int*, core::int*>{};
+    #t3.{core::Map::[]=}{Invariant}(1, 1){(core::int*, core::int*) →* void};
+    if(self::oracle() as{TypeError,ForDynamic} core::bool*)
+      #t3.{core::Map::[]=}{Invariant}(2, 2){(core::int*, core::int*) →* void};
+    if(self::oracle() as{TypeError,ForDynamic} core::bool*)
+      #t3.{core::Map::[]=}{Invariant}(3, 3){(core::int*, core::int*) →* void};
+    else
+      #t3.{core::Map::[]=}{Invariant}(1.{core::int::unary-}(){() →* core::int*}, 1.{core::int::unary-}(){() →* core::int*}){(core::int*, core::int*) →* void};
+    if(self::oracle() as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle() as{TypeError,ForDynamic} core::bool*)
+        #t3.{core::Map::[]=}{Invariant}(4, 4){(core::int*, core::int*) →* void};
+    for (core::int* i in <core::int*>[5, 6, 7])
+      #t3.{core::Map::[]=}{Invariant}(i, i){(core::int*, core::int*) →* void};
+    for (core::int* i in <core::int*>[8, 9, 10])
+      if(self::oracle() as{TypeError,ForDynamic} core::bool*)
+        #t3.{core::Map::[]=}{Invariant}(i, i){(core::int*, core::int*) →* void};
+    for (core::int* i = 11; i.{core::num::<=}(14){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t3.{core::Map::[]=}{Invariant}(i, i){(core::int*, core::int*) →* void};
+  } =>#t3;
+  core::print(aList);
+  core::print(aSet);
+  core::print(aMap);
+}
+static method oracle() → dynamic
+  return true;
diff --git a/pkg/front_end/testcases/general/control_flow_collection_inference.dart.weak.modular.expect b/pkg/front_end/testcases/general/control_flow_collection_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..2ebf6f7
--- /dev/null
+++ b/pkg/front_end/testcases/general/control_flow_collection_inference.dart.weak.modular.expect
@@ -0,0 +1,2158 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:39:34: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+//   Map<String, List<int>> map40 = {if (oracle("foo")) ...{"bar", []}, "baz": null};
+//                                  ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:71:38: Error: Unexpected type 'Map<String, int>' of a spread.  Expected 'dynamic' or an Iterable.
+//  - 'Map' is from 'dart:core'.
+//   var map82 = {if (oracle("foo")) ...mapToInt else ...dynVar, null};
+//                                      ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:106:44: Error: Expected ':' after this.
+//   Set<dynamic> set10 = {if (oracle("foo")) 42 else "bar": 3.14};
+//                                            ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:107:53: Error: Expected ':' after this.
+//   Map<dynamic, dynamic> map10 = {if (oracle("foo")) 42 else "bar": 3.14};
+//                                                     ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:108:61: Error: Expected ':' after this.
+//   Set<dynamic> set11 = {if (oracle("foo")) "bar": 3.14 else 42};
+//                                                             ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:109:70: Error: Expected ':' after this.
+//   Map<dynamic, dynamic> map11 = {if (oracle("foo")) "bar": 3.14 else 42};
+//                                                                      ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:110:35: Error: Expected ':' after this.
+//   var map12 = {if (oracle("foo")) 42 else "bar": 3.14};
+//                                   ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:111:52: Error: Expected ':' after this.
+//   var map13 = {if (oracle("foo")) "bar": 3.14 else 42};
+//                                                    ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:87:28: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <int>[if (oracle("foo")) "bar"];
+//                            ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:88:28: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <int>{if (oracle("foo")) "bar", null};
+//                            ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:89:43: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <String, int>{if (oracle("foo")) "bar": "bar", "baz": null};
+//                                           ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:90:32: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <int>[if (oracle("foo")) ...["bar"]];
+//                                ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:91:32: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <int>{if (oracle("foo")) ...["bar"], null};
+//                                ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:92:47: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <String, int>{if (oracle("foo")) ...{"bar": "bar"}, "baz": null};
+//                                               ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:93:31: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+//  - 'Map' is from 'dart:core'.
+//   <int>[if (oracle("foo")) ...map];
+//                               ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:94:31: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+//  - 'Map' is from 'dart:core'.
+//   <int>{if (oracle("foo")) ...map, null};
+//                               ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:95:39: Error: Unexpected type 'List<String>' of a map spread entry.  Expected 'dynamic' or a Map.
+//  - 'List' is from 'dart:core'.
+//   <String, int>{if (oracle("foo")) ...["bar"], "baz": null};
+//                                       ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:96:31: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   <String>[if (oracle("foo")) 42 else 3.14];
+//                               ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:96:39: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+//   <String>[if (oracle("foo")) 42 else 3.14];
+//                                       ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:97:31: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   <String>{if (oracle("foo")) 42 else 3.14, null};
+//                               ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:97:39: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+//   <String>{if (oracle("foo")) 42 else 3.14, null};
+//                                       ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:98:46: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   <String, String>{if (oracle("foo")) "bar": 42 else "baz": 3.14, "baz": null};
+//                                              ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:98:61: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+//   <String, String>{if (oracle("foo")) "bar": 42 else "baz": 3.14, "baz": null};
+//                                                             ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:99:31: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+//  - 'Map' is from 'dart:core'.
+//   <int>[if (oracle("foo")) ...map else 42];
+//                               ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:100:31: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+//  - 'Map' is from 'dart:core'.
+//   <int>{if (oracle("foo")) ...map else 42, null};
+//                               ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:101:39: Error: Unexpected type 'List<int>' of a map spread entry.  Expected 'dynamic' or a Map.
+//  - 'List' is from 'dart:core'.
+//   <String, int>{if (oracle("foo")) ...[42] else "bar": 42, "baz": null};
+//                                       ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:102:39: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+//  - 'Map' is from 'dart:core'.
+//   <int>[if (oracle("foo")) 42 else ...map];
+//                                       ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:103:31: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+//  - 'Map' is from 'dart:core'.
+//   <int>{if (oracle("foo")) ...map else 42, null};
+//                               ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:104:54: Error: Unexpected type 'List<int>' of a map spread entry.  Expected 'dynamic' or a Map.
+//  - 'List' is from 'dart:core'.
+//   <String, int>{if (oracle("foo")) "bar": 42 else ...[42], "baz": null};
+//                                                      ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:106:24: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+//   Set<dynamic> set10 = {if (oracle("foo")) 42 else "bar": 3.14};
+//                        ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:108:24: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+//   Set<dynamic> set11 = {if (oracle("foo")) "bar": 3.14 else 42};
+//                        ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:112:27: Error: A value of type 'int' can't be assigned to a variable of type 'bool'.
+//   List<int> list20 = [if (42) 42];
+//                           ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:113:25: Error: A value of type 'int' can't be assigned to a variable of type 'bool'.
+//   Set<int> set20 = {if (42) 42};
+//                         ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:114:30: Error: A value of type 'int' can't be assigned to a variable of type 'bool'.
+//   Map<int, int> map30 = {if (42) 42: 42};
+//                              ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:115:53: Error: A value of type 'bool' can't be assigned to a variable of type 'String'.
+//   List<String> list40 = <String>[if (oracle("foo")) true else 42];
+//                                                     ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:115:63: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   List<String> list40 = <String>[if (oracle("foo")) true else 42];
+//                                                               ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:116:51: Error: A value of type 'bool' can't be assigned to a variable of type 'String'.
+//   Set<String> set40 = <String>{if (oracle("foo")) true else 42};
+//                                                   ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:116:61: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   Set<String> set40 = <String>{if (oracle("foo")) true else 42};
+//                                                             ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:117:61: Error: A value of type 'bool' can't be assigned to a variable of type 'String'.
+//   Map<String, int> map40 = <String, int>{if (oracle("foo")) true: 42 else 42: 42};
+//                                                             ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:117:75: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   Map<String, int> map40 = <String, int>{if (oracle("foo")) true: 42 else 42: 42};
+//                                                                           ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:118:65: Error: A value of type 'bool' can't be assigned to a variable of type 'String'.
+//   Map<int, String> map41 = <int, String>{if (oracle("foo")) 42: true else 42: 42};
+//                                                                 ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:118:79: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   Map<int, String> map41 = <int, String>{if (oracle("foo")) 42: true else 42: 42};
+//                                                                               ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:230:14: Error: Can't assign to the final variable 'i'.
+//   <int>[for (i in <int>[1]) i];
+//              ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:231:14: Error: Can't assign to the final variable 'i'.
+//   <int>{for (i in <int>[1]) i, null};
+//              ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:232:21: Error: Can't assign to the final variable 'i'.
+// 	<String, int>{for (i in <int>[1]) "bar": i, "baz": null};
+// 	                   ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:246:17: Error: The keyword 'await' isn't allowed for a normal 'for' statement.
+// Try removing the keyword, or use a for-each statement.
+//   var list50 = [await for (;;) 42];
+//                 ^^^^^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:247:16: Error: The keyword 'await' isn't allowed for a normal 'for' statement.
+// Try removing the keyword, or use a for-each statement.
+//   var set50 = {await for (;;) 42, null};
+//                ^^^^^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:248:16: Error: The keyword 'await' isn't allowed for a normal 'for' statement.
+// Try removing the keyword, or use a for-each statement.
+//   var map50 = {await for (;;) "bar": 42, "baz": null};
+//                ^^^^^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:210:45: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <int>[for (int i = 0; oracle("foo"); i++) "bar"];
+//                                             ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:211:45: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <int>{for (int i = 0; oracle("foo"); i++) "bar", null};
+//                                             ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:212:50: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <int, int>{for (int i = 0; oracle("foo"); i++) "bar": "bar", "baz": null};
+//                                                  ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:212:57: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <int, int>{for (int i = 0; oracle("foo"); i++) "bar": "bar", "baz": null};
+//                                                         ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:212:64: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <int, int>{for (int i = 0; oracle("foo"); i++) "bar": "bar", "baz": null};
+//                                                                ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:213:49: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <int>[for (int i = 0; oracle("foo"); i++) ...["bar"]];
+//                                                 ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:214:49: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <int>{for (int i = 0; oracle("foo"); i++) ...["bar"], null};
+//                                                 ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:215:54: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <int, int>{for (int i = 0; oracle("foo"); i++) ...{"bar": "bar"}, "baz": null};
+//                                                      ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:215:61: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <int, int>{for (int i = 0; oracle("foo"); i++) ...{"bar": "bar"}, "baz": null};
+//                                                             ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:215:69: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   <int, int>{for (int i = 0; oracle("foo"); i++) ...{"bar": "bar"}, "baz": null};
+//                                                                     ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:216:48: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+//  - 'Map' is from 'dart:core'.
+//   <int>[for (int i = 0; oracle("foo"); i++) ...map];
+//                                                ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:217:48: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+//  - 'Map' is from 'dart:core'.
+//   <int>{for (int i = 0; oracle("foo"); i++) ...map, null};
+//                                                ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:218:53: Error: Unexpected type 'List<int>' of a map spread entry.  Expected 'dynamic' or a Map.
+//  - 'List' is from 'dart:core'.
+//   <int, int>{for (int i = 0; oracle("foo"); i++) ...list, 42: null};
+//                                                     ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:219:62: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   <String>[for (int i = 0; oracle("foo"); i++) if (oracle()) 42 else 3.14];
+//                                                              ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:219:70: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+//   <String>[for (int i = 0; oracle("foo"); i++) if (oracle()) 42 else 3.14];
+//                                                                      ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:220:62: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   <String>{for (int i = 0; oracle("foo"); i++) if (oracle()) 42 else 3.14, null};
+//                                                              ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:220:70: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+//   <String>{for (int i = 0; oracle("foo"); i++) if (oracle()) 42 else 3.14, null};
+//                                                                      ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:221:77: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   <String, String>{for (int i = 0; oracle("foo"); i++) if (oracle()) "bar": 42 else "bar": 3.14, "baz": null};
+//                                                                             ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:221:92: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+//   <String, String>{for (int i = 0; oracle("foo"); i++) if (oracle()) "bar": 42 else "bar": 3.14, "baz": null};
+//                                                                                            ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:222:62: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+//  - 'Map' is from 'dart:core'.
+//   <int>[for (int i = 0; oracle("foo"); i++) if (oracle()) ...map else 42];
+//                                                              ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:223:62: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+//  - 'Map' is from 'dart:core'.
+//   <int>{for (int i = 0; oracle("foo"); i++) if (oracle()) ...map else 42, null};
+//                                                              ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:224:70: Error: Unexpected type 'List<int>' of a map spread entry.  Expected 'dynamic' or a Map.
+//  - 'List' is from 'dart:core'.
+//   <String, int>{for (int i = 0; oracle("foo"); i++) if (oracle()) ...list else "bar": 42, "baz": null};
+//                                                                      ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:225:70: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+//  - 'Map' is from 'dart:core'.
+//   <int>[for (int i = 0; oracle("foo"); i++) if (oracle()) 42 else ...map];
+//                                                                      ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:226:70: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+//  - 'Map' is from 'dart:core'.
+//   <int>{for (int i = 0; oracle("foo"); i++) if (oracle()) 42 else ...map, null};
+//                                                                      ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:227:85: Error: Unexpected type 'List<int>' of a map spread entry.  Expected 'dynamic' or a Map.
+//  - 'List' is from 'dart:core'.
+//   <String, int>{for (int i = 0; oracle("foo"); i++) if (oracle()) "bar": 42 else ...list, "baz": null};
+//                                                                                     ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:234:31: Error: The type 'String' used in the 'for' loop must implement 'Iterable<dynamic>'.
+//  - 'Iterable' is from 'dart:core'.
+//   var list10 = [for (var i in "not iterable") i];
+//                               ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:235:30: Error: The type 'String' used in the 'for' loop must implement 'Iterable<dynamic>'.
+//  - 'Iterable' is from 'dart:core'.
+//   var set10 = {for (var i in "not iterable") i, null};
+//                              ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:236:30: Error: The type 'String' used in the 'for' loop must implement 'Iterable<dynamic>'.
+//  - 'Iterable' is from 'dart:core'.
+//   var map10 = {for (var i in "not iterable") "bar": i, "baz": null};
+//                              ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:237:32: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   var list20 = [for (int i in ["not", "int"]) i];
+//                                ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:237:39: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   var list20 = [for (int i in ["not", "int"]) i];
+//                                       ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:238:31: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   var set20 = {for (int i in ["not", "int"]) i, null};
+//                               ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:238:38: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   var set20 = {for (int i in ["not", "int"]) i, null};
+//                                      ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:239:31: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   var map20 = {for (int i in ["not", "int"]) "bar": i, "baz": null};
+//                               ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:239:38: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   var map20 = {for (int i in ["not", "int"]) "bar": i, "baz": null};
+//                                      ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:240:37: Error: The type 'String' used in the 'for' loop must implement 'Stream<dynamic>'.
+//  - 'Stream' is from 'dart:async'.
+//   var list30 = [await for (var i in "not stream") i];
+//                                     ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:241:36: Error: The type 'String' used in the 'for' loop must implement 'Stream<dynamic>'.
+//  - 'Stream' is from 'dart:async'.
+//   var set30 = {await for (var i in "not stream") i, null};
+//                                    ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:242:36: Error: The type 'String' used in the 'for' loop must implement 'Stream<dynamic>'.
+//  - 'Stream' is from 'dart:async'.
+//   var map30 = {await for (var i in "not stream") "bar": i, "baz": null};
+//                                    ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:243:58: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   var list40 = [await for (int i in Stream.fromIterable(["not", "int"])) i];
+//                                                          ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:243:65: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   var list40 = [await for (int i in Stream.fromIterable(["not", "int"])) i];
+//                                                                 ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:244:57: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   var set40 = {await for (int i in Stream.fromIterable(["not", "int"])) i, null};
+//                                                         ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:244:64: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   var set40 = {await for (int i in Stream.fromIterable(["not", "int"])) i, null};
+//                                                                ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:245:57: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   var map40 = {await for (int i in Stream.fromIterable(["not", "int"])) "bar": i, "baz": null};
+//                                                         ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:245:64: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   var map40 = {await for (int i in Stream.fromIterable(["not", "int"])) "bar": i, "baz": null};
+//                                                                ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:249:24: Error: A value of type 'String' can't be assigned to a variable of type 'bool'.
+//   var list60 = [for (; "not bool";) 42];
+//                        ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:250:23: Error: A value of type 'String' can't be assigned to a variable of type 'bool'.
+//   var set60 = {for (; "not bool";) 42, null};
+//                       ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:251:23: Error: A value of type 'String' can't be assigned to a variable of type 'bool'.
+//   var map60 = {for (; "not bool";) "bar": 42, "baz": null};
+//                       ^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:255:26: Error: The asynchronous for-in can only be used in functions marked with 'async' or 'async*'.
+// Try marking the function body with either 'async' or 'async*', or removing the 'await' before the for loop.
+//   <int>[await for (int i in stream) i];
+//                          ^^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:256:26: Error: The asynchronous for-in can only be used in functions marked with 'async' or 'async*'.
+// Try marking the function body with either 'async' or 'async*', or removing the 'await' before the for loop.
+//   <int>{await for (int i in stream) i};
+//                          ^^
+//
+// pkg/front_end/testcases/general/control_flow_collection_inference.dart:257:34: Error: The asynchronous for-in can only be used in functions marked with 'async' or 'async*'.
+// Try marking the function body with either 'async' or 'async*', or removing the 'await' before the for loop.
+//   <String, int>{await for (int i in stream) "bar": i};
+//                                  ^^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+import "dart:async" as asy;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  get foo() → core::int*
+    return 42;
+}
+static method oracle<T extends core::Object* = dynamic>([self::oracle::T* t = #C1]) → dynamic
+  return true;
+static method testIfElement(dynamic dynVar, core::List<core::int*>* listInt, core::List<core::double*>* listDouble, core::Map<core::String*, core::int*>* mapToInt, core::Map<core::String*, core::double*>* mapToDouble) → dynamic {
+  core::List<core::int*>* list10 = block {
+    final core::List<core::int*>* #t1 = <core::int*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t1.{core::List::add}{Invariant}(42){(core::int*) →* void};
+  } =>#t1;
+  core::Set<core::int*>* set10 = block {
+    final core::Set<core::int*>* #t2 = col::LinkedHashSet::•<core::int*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t2.{core::Set::add}{Invariant}(42){(core::int*) →* core::bool*};
+    #t2.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t2;
+  core::Map<core::String*, core::int*>* map10 = block {
+    final core::Map<core::String*, core::int*>* #t3 = <core::String*, core::int*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t3.{core::Map::[]=}{Invariant}("bar", 42){(core::String*, core::int*) →* void};
+    #t3.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t3;
+  core::List<dynamic>* list11 = block {
+    final core::List<dynamic>* #t4 = <dynamic>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t4.{core::List::add}{Invariant}(dynVar){(dynamic) →* void};
+  } =>#t4;
+  core::Set<dynamic>* set11 = block {
+    final core::Set<dynamic>* #t5 = col::LinkedHashSet::•<dynamic>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t5.{core::Set::add}{Invariant}(dynVar){(dynamic) →* core::bool*};
+    #t5.{core::Set::add}{Invariant}(null){(dynamic) →* core::bool*};
+  } =>#t5;
+  core::Map<core::String*, dynamic>* map11 = block {
+    final core::Map<core::String*, dynamic>* #t6 = <core::String*, dynamic>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t6.{core::Map::[]=}{Invariant}("bar", dynVar){(core::String*, dynamic) →* void};
+    #t6.{core::Map::[]=}{Invariant}("baz", null){(core::String*, dynamic) →* void};
+  } =>#t6;
+  core::List<core::List<core::int*>*>* list12 = block {
+    final core::List<core::List<core::int*>*>* #t7 = <core::List<core::int*>*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t7.{core::List::add}{Invariant}(<core::int*>[42]){(core::List<core::int*>*) →* void};
+  } =>#t7;
+  core::Set<core::List<core::int*>*>* set12 = block {
+    final core::Set<core::List<core::int*>*>* #t8 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t8.{core::Set::add}{Invariant}(<core::int*>[42]){(core::List<core::int*>*) →* core::bool*};
+    #t8.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t8;
+  core::Map<core::String*, core::List<core::int*>*>* map12 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t9 = <core::String*, core::List<core::int*>*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t9.{core::Map::[]=}{Invariant}("bar", <core::int*>[42]){(core::String*, core::List<core::int*>*) →* void};
+    #t9.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t9;
+  core::List<core::int*>* list20 = block {
+    final core::List<core::int*>* #t10 = <core::int*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t10.{core::List::addAll}{Invariant}(<core::int*>[42]){(core::Iterable<core::int*>*) →* void};
+  } =>#t10;
+  core::Set<core::int*>* set20 = block {
+    final core::Set<core::int*>* #t11 = col::LinkedHashSet::•<core::int*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t11.{core::Set::addAll}{Invariant}(<core::int*>[42]){(core::Iterable<core::int*>*) →* void};
+    #t11.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t11;
+  core::Map<core::String*, core::int*>* map20 = block {
+    final core::Map<core::String*, core::int*>* #t12 = <core::String*, core::int*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      for (final core::MapEntry<core::String*, core::int*>* #t13 in <core::String*, core::int*>{"bar": 42}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>})
+        #t12.{core::Map::[]=}{Invariant}(#t13.{core::MapEntry::key}{core::String*}, #t13.{core::MapEntry::value}{core::int*}){(core::String*, core::int*) →* void};
+    #t12.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t12;
+  core::List<dynamic>* list21 = block {
+    final core::List<dynamic>* #t14 = <dynamic>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t14.{core::List::addAll}{Invariant}(<dynamic>[dynVar]){(core::Iterable<dynamic>*) →* void};
+  } =>#t14;
+  core::Set<dynamic>* set21 = block {
+    final core::Set<dynamic>* #t15 = col::LinkedHashSet::•<dynamic>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t15.{core::Set::addAll}{Invariant}(<dynamic>[dynVar]){(core::Iterable<dynamic>*) →* void};
+    #t15.{core::Set::add}{Invariant}(null){(dynamic) →* core::bool*};
+  } =>#t15;
+  core::Map<core::String*, dynamic>* map21 = block {
+    final core::Map<core::String*, dynamic>* #t16 = <core::String*, dynamic>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      for (final core::MapEntry<core::String*, dynamic>* #t17 in <core::String*, dynamic>{"bar": dynVar}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, dynamic>>})
+        #t16.{core::Map::[]=}{Invariant}(#t17.{core::MapEntry::key}{core::String*}, #t17.{core::MapEntry::value}{dynamic}){(core::String*, dynamic) →* void};
+    #t16.{core::Map::[]=}{Invariant}("baz", null){(core::String*, dynamic) →* void};
+  } =>#t16;
+  core::List<core::List<core::int*>*>* list22 = block {
+    final core::List<core::List<core::int*>*>* #t18 = <core::List<core::int*>*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t18.{core::List::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[42]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+  } =>#t18;
+  core::Set<core::List<core::int*>*>* set22 = block {
+    final core::Set<core::List<core::int*>*>* #t19 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t19.{core::Set::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[42]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+    #t19.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t19;
+  core::Map<core::String*, core::List<core::int*>*>* map22 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t20 = <core::String*, core::List<core::int*>*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      for (final core::MapEntry<core::String*, core::List<core::int*>*>* #t21 in <core::String*, core::List<core::int*>*>{"bar": <core::int*>[42]}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::List<core::int*>*>>})
+        #t20.{core::Map::[]=}{Invariant}(#t21.{core::MapEntry::key}{core::String*}, #t21.{core::MapEntry::value}{core::List<core::int*>*}){(core::String*, core::List<core::int*>*) →* void};
+    #t20.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t20;
+  core::List<core::int*>* list30 = block {
+    final core::List<core::int*>* #t22 = <core::int*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t22.{core::List::addAll}{Invariant}(<core::int*>[42]){(core::Iterable<core::int*>*) →* void};
+  } =>#t22;
+  core::Set<core::int*>* set30 = block {
+    final core::Set<core::int*>* #t23 = col::LinkedHashSet::•<core::int*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t23.{core::Set::addAll}{Invariant}(<core::int*>[42]){(core::Iterable<core::int*>*) →* void};
+    #t23.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t23;
+  core::Map<core::String*, core::int*>* map30 = block {
+    final core::Map<core::String*, core::int*>* #t24 = <core::String*, core::int*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        for (final core::MapEntry<core::String*, core::int*>* #t25 in <core::String*, core::int*>{"bar": 42}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>})
+          #t24.{core::Map::[]=}{Invariant}(#t25.{core::MapEntry::key}{core::String*}, #t25.{core::MapEntry::value}{core::int*}){(core::String*, core::int*) →* void};
+    #t24.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t24;
+  core::List<dynamic>* list31 = block {
+    final core::List<dynamic>* #t26 = <dynamic>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t26.{core::List::addAll}{Invariant}(<dynamic>[dynVar]){(core::Iterable<dynamic>*) →* void};
+  } =>#t26;
+  core::Set<dynamic>* set31 = block {
+    final core::Set<dynamic>* #t27 = col::LinkedHashSet::•<dynamic>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t27.{core::Set::addAll}{Invariant}(<dynamic>[dynVar]){(core::Iterable<dynamic>*) →* void};
+    #t27.{core::Set::add}{Invariant}(null){(dynamic) →* core::bool*};
+  } =>#t27;
+  core::Map<core::String*, dynamic>* map31 = block {
+    final core::Map<core::String*, dynamic>* #t28 = <core::String*, dynamic>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        for (final core::MapEntry<core::String*, dynamic>* #t29 in <core::String*, dynamic>{"bar": dynVar}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, dynamic>>})
+          #t28.{core::Map::[]=}{Invariant}(#t29.{core::MapEntry::key}{core::String*}, #t29.{core::MapEntry::value}{dynamic}){(core::String*, dynamic) →* void};
+    #t28.{core::Map::[]=}{Invariant}("baz", null){(core::String*, dynamic) →* void};
+  } =>#t28;
+  core::List<core::List<core::int*>*>* list33 = block {
+    final core::List<core::List<core::int*>*>* #t30 = <core::List<core::int*>*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t30.{core::List::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[42]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+  } =>#t30;
+  core::Set<core::List<core::int*>*>* set33 = block {
+    final core::Set<core::List<core::int*>*>* #t31 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t31.{core::Set::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[42]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+    #t31.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t31;
+  core::Map<core::String*, core::List<core::int*>*>* map33 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t32 = <core::String*, core::List<core::int*>*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        for (final core::MapEntry<core::String*, core::List<core::int*>*>* #t33 in <core::String*, core::List<core::int*>*>{"bar": <core::int*>[42]}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::List<core::int*>*>>})
+          #t32.{core::Map::[]=}{Invariant}(#t33.{core::MapEntry::key}{core::String*}, #t33.{core::MapEntry::value}{core::List<core::int*>*}){(core::String*, core::List<core::int*>*) →* void};
+    #t32.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t32;
+  core::List<core::List<core::int*>*>* list40 = block {
+    final core::List<core::List<core::int*>*>* #t34 = <core::List<core::int*>*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t34.{core::List::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+  } =>#t34;
+  core::Set<core::List<core::int*>*>* set40 = block {
+    final core::Set<core::List<core::int*>*>* #t35 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t35.{core::Set::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+    #t35.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t35;
+  core::Map<core::String*, core::List<core::int*>*>* map40 = invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:39:34: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+  Map<String, List<int>> map40 = {if (oracle(\"foo\")) ...{\"bar\", []}, \"baz\": null};
+                                 ^";
+  core::List<core::List<core::int*>*>* list41 = block {
+    final core::List<core::List<core::int*>*>* #t36 = <core::List<core::int*>*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t36.{core::List::addAll}{Invariant}( block {
+        final core::Set<core::List<core::int*>*>* #t37 = col::LinkedHashSet::•<core::List<core::int*>*>();
+        #t37.{core::Set::add}{Invariant}(<core::int*>[]){(core::List<core::int*>*) →* core::bool*};
+      } =>#t37){(core::Iterable<core::List<core::int*>*>*) →* void};
+  } =>#t36;
+  core::Set<core::List<core::int*>*>* set41 = block {
+    final core::Set<core::List<core::int*>*>* #t38 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t38.{core::Set::addAll}{Invariant}( block {
+        final core::Set<core::List<core::int*>*>* #t39 = col::LinkedHashSet::•<core::List<core::int*>*>();
+        #t39.{core::Set::add}{Invariant}(<core::int*>[]){(core::List<core::int*>*) →* core::bool*};
+      } =>#t39){(core::Iterable<core::List<core::int*>*>*) →* void};
+    #t38.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t38;
+  core::List<core::List<core::int*>*>* list42 = block {
+    final core::List<core::List<core::int*>*>* #t40 = <core::List<core::int*>*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t40.{core::List::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+  } =>#t40;
+  core::Set<core::List<core::int*>*>* set42 = block {
+    final core::Set<core::List<core::int*>*>* #t41 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t41.{core::Set::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+    #t41.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t41;
+  core::Map<core::String*, core::List<core::int*>*>* map42 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t42 = <core::String*, core::List<core::int*>*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        for (final core::MapEntry<core::String*, core::List<core::int*>*>* #t43 in <core::String*, core::List<core::int*>*>{"bar": <core::int*>[]}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::List<core::int*>*>>})
+          #t42.{core::Map::[]=}{Invariant}(#t43.{core::MapEntry::key}{core::String*}, #t43.{core::MapEntry::value}{core::List<core::int*>*}){(core::String*, core::List<core::int*>*) →* void};
+    #t42.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t42;
+  core::List<core::int*>* list50 = block {
+    final core::List<core::int*>* #t44 = <core::int*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t44.{core::List::addAll}{Invariant}(<core::int*>[]){(core::Iterable<core::int*>*) →* void};
+  } =>#t44;
+  core::Set<core::int*>* set50 = block {
+    final core::Set<core::int*>* #t45 = col::LinkedHashSet::•<core::int*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t45.{core::Set::addAll}{Invariant}(<core::int*>[]){(core::Iterable<core::int*>*) →* void};
+    #t45.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t45;
+  core::Map<core::String*, core::int*>* map50 = block {
+    final core::Map<core::String*, core::int*>* #t46 = <core::String*, core::int*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      for (final core::MapEntry<core::String*, core::int*>* #t47 in <core::String*, core::int*>{}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>})
+        #t46.{core::Map::[]=}{Invariant}(#t47.{core::MapEntry::key}{core::String*}, #t47.{core::MapEntry::value}{core::int*}){(core::String*, core::int*) →* void};
+    #t46.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t46;
+  core::List<core::int*>* list51 = block {
+    final core::List<core::int*>* #t48 = <core::int*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t48.{core::List::addAll}{Invariant}( block {
+        final core::Set<core::int*>* #t49 = col::LinkedHashSet::•<core::int*>();
+      } =>#t49){(core::Iterable<core::int*>*) →* void};
+  } =>#t48;
+  core::Set<core::int*>* set51 = block {
+    final core::Set<core::int*>* #t50 = col::LinkedHashSet::•<core::int*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t50.{core::Set::addAll}{Invariant}( block {
+        final core::Set<core::int*>* #t51 = col::LinkedHashSet::•<core::int*>();
+      } =>#t51){(core::Iterable<core::int*>*) →* void};
+    #t50.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t50;
+  core::List<core::int*>* list52 = block {
+    final core::List<core::int*>* #t52 = <core::int*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t52.{core::List::addAll}{Invariant}(<core::int*>[]){(core::Iterable<core::int*>*) →* void};
+  } =>#t52;
+  core::Set<core::int*>* set52 = block {
+    final core::Set<core::int*>* #t53 = col::LinkedHashSet::•<core::int*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t53.{core::Set::addAll}{Invariant}(<core::int*>[]){(core::Iterable<core::int*>*) →* void};
+    #t53.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t53;
+  core::Map<core::String*, core::int*>* map52 = block {
+    final core::Map<core::String*, core::int*>* #t54 = <core::String*, core::int*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        for (final core::MapEntry<core::String*, core::int*>* #t55 in <core::String*, core::int*>{}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>})
+          #t54.{core::Map::[]=}{Invariant}(#t55.{core::MapEntry::key}{core::String*}, #t55.{core::MapEntry::value}{core::int*}){(core::String*, core::int*) →* void};
+    #t54.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t54;
+  core::List<core::List<core::int*>*>* list60 = block {
+    final core::List<core::List<core::int*>*>* #t56 = <core::List<core::int*>*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t56.{core::List::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+  } =>#t56;
+  core::Set<core::List<core::int*>*>* set60 = block {
+    final core::Set<core::List<core::int*>*>* #t57 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t57.{core::Set::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+    #t57.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t57;
+  core::Map<core::String*, core::List<core::int*>*>* map60 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t58 = <core::String*, core::List<core::int*>*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      for (final core::MapEntry<core::String*, core::List<core::int*>*>* #t59 in <core::String*, core::List<core::int*>*>{"bar": <core::int*>[]}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::List<core::int*>*>>})
+        #t58.{core::Map::[]=}{Invariant}(#t59.{core::MapEntry::key}{core::String*}, #t59.{core::MapEntry::value}{core::List<core::int*>*}){(core::String*, core::List<core::int*>*) →* void};
+    #t58.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t58;
+  core::List<core::List<core::int*>*>* list61 = block {
+    final core::List<core::List<core::int*>*>* #t60 = <core::List<core::int*>*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t60.{core::List::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+  } =>#t60;
+  core::Set<core::List<core::int*>*>* set61 = block {
+    final core::Set<core::List<core::int*>*>* #t61 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t61.{core::Set::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+    #t61.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t61;
+  core::Map<core::String*, core::List<core::int*>*>* map61 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t62 = <core::String*, core::List<core::int*>*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        for (final core::MapEntry<core::String*, core::List<core::int*>*>* #t63 in <core::String*, core::List<core::int*>*>{"bar": <core::int*>[]}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::List<core::int*>*>>})
+          #t62.{core::Map::[]=}{Invariant}(#t63.{core::MapEntry::key}{core::String*}, #t63.{core::MapEntry::value}{core::List<core::int*>*}){(core::String*, core::List<core::int*>*) →* void};
+    #t62.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t62;
+  core::List<core::List<core::int*>*>* list70 = block {
+    final core::List<core::List<core::int*>*>* #t64 = <core::List<core::int*>*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t64.{core::List::add}{Invariant}(<core::int*>[]){(core::List<core::int*>*) →* void};
+  } =>#t64;
+  core::Set<core::List<core::int*>*>* set70 = block {
+    final core::Set<core::List<core::int*>*>* #t65 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t65.{core::Set::add}{Invariant}(<core::int*>[]){(core::List<core::int*>*) →* core::bool*};
+    #t65.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t65;
+  core::List<core::List<core::int*>*>* list71 = block {
+    final core::List<core::List<core::int*>*>* #t66 = <core::List<core::int*>*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t66.{core::List::add}{Invariant}(<core::int*>[]){(core::List<core::int*>*) →* void};
+  } =>#t66;
+  core::Set<core::List<core::int*>*>* set71 = block {
+    final core::Set<core::List<core::int*>*>* #t67 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t67.{core::Set::add}{Invariant}(<core::int*>[]){(core::List<core::int*>*) →* core::bool*};
+    #t67.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t67;
+  core::List<core::num*>* list80 = block {
+    final core::List<core::num*>* #t68 = <core::num*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t68.{core::List::add}{Invariant}(42){(core::num*) →* void};
+    else
+      #t68.{core::List::add}{Invariant}(3.14){(core::num*) →* void};
+  } =>#t68;
+  core::Set<core::num*>* set80 = block {
+    final core::Set<core::num*>* #t69 = col::LinkedHashSet::•<core::num*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t69.{core::Set::add}{Invariant}(42){(core::num*) →* core::bool*};
+    else
+      #t69.{core::Set::add}{Invariant}(3.14){(core::num*) →* core::bool*};
+    #t69.{core::Set::add}{Invariant}(null){(core::num*) →* core::bool*};
+  } =>#t69;
+  core::Map<core::String*, core::num*>* map80 = block {
+    final core::Map<core::String*, core::num*>* #t70 = <core::String*, core::num*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t70.{core::Map::[]=}{Invariant}("bar", 42){(core::String*, core::num*) →* void};
+    else
+      #t70.{core::Map::[]=}{Invariant}("bar", 3.14){(core::String*, core::num*) →* void};
+    #t70.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::num*) →* void};
+  } =>#t70;
+  core::List<core::num*>* list81 = block {
+    final core::List<core::num*>* #t71 = <core::num*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t71.{core::List::addAll}{Invariant}(listInt){(core::Iterable<core::num*>*) →* void};
+    else
+      #t71.{core::List::addAll}{Invariant}(listDouble){(core::Iterable<core::num*>*) →* void};
+  } =>#t71;
+  core::Set<core::num*>* set81 = block {
+    final core::Set<core::num*>* #t72 = col::LinkedHashSet::•<core::num*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t72.{core::Set::addAll}{Invariant}(listInt){(core::Iterable<core::num*>*) →* void};
+    else
+      #t72.{core::Set::addAll}{Invariant}(listDouble){(core::Iterable<core::num*>*) →* void};
+    #t72.{core::Set::add}{Invariant}(null){(core::num*) →* core::bool*};
+  } =>#t72;
+  core::Map<core::String*, core::num*>* map81 = block {
+    final core::Map<core::String*, core::num*>* #t73 = <core::String*, core::num*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      for (final core::MapEntry<core::String*, core::num*>* #t74 in mapToInt.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::num*>>})
+        #t73.{core::Map::[]=}{Invariant}(#t74.{core::MapEntry::key}{core::String*}, #t74.{core::MapEntry::value}{core::num*}){(core::String*, core::num*) →* void};
+    else
+      for (final core::MapEntry<core::String*, core::num*>* #t75 in mapToDouble.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::num*>>})
+        #t73.{core::Map::[]=}{Invariant}(#t75.{core::MapEntry::key}{core::String*}, #t75.{core::MapEntry::value}{core::num*}){(core::String*, core::num*) →* void};
+    #t73.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::num*) →* void};
+  } =>#t73;
+  core::List<dynamic>* list82 = block {
+    final core::List<dynamic>* #t76 = <dynamic>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t76.{core::List::addAll}{Invariant}(listInt){(core::Iterable<dynamic>*) →* void};
+    else
+      #t76.{core::List::addAll}{Invariant}(dynVar as{TypeError,ForDynamic} core::Iterable<dynamic>*){(core::Iterable<dynamic>*) →* void};
+  } =>#t76;
+  core::Set<dynamic>* set82 = block {
+    final core::Set<dynamic>* #t77 = col::LinkedHashSet::•<dynamic>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t77.{core::Set::addAll}{Invariant}(listInt){(core::Iterable<dynamic>*) →* void};
+    else
+      #t77.{core::Set::addAll}{Invariant}(dynVar as{TypeError,ForDynamic} core::Iterable<dynamic>*){(core::Iterable<dynamic>*) →* void};
+    #t77.{core::Set::add}{Invariant}(null){(dynamic) →* core::bool*};
+  } =>#t77;
+  core::Set<dynamic>* map82 = block {
+    final core::Set<dynamic>* #t78 = col::LinkedHashSet::•<dynamic>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t78.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:71:38: Error: Unexpected type 'Map<String, int>' of a spread.  Expected 'dynamic' or an Iterable.
+ - 'Map' is from 'dart:core'.
+  var map82 = {if (oracle(\"foo\")) ...mapToInt else ...dynVar, null};
+                                     ^"){(dynamic) →* core::bool*};
+    else
+      #t78.{core::Set::addAll}{Invariant}(dynVar as{TypeError,ForDynamic} core::Iterable<dynamic>*){(core::Iterable<dynamic>*) →* void};
+    #t78.{core::Set::add}{Invariant}(null){(dynamic) →* core::bool*};
+  } =>#t78;
+  core::List<core::num*>* list83 = block {
+    final core::List<core::num*>* #t79 = <core::num*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t79.{core::List::add}{Invariant}(42){(core::num*) →* void};
+    else
+      #t79.{core::List::addAll}{Invariant}(listDouble){(core::Iterable<core::num*>*) →* void};
+  } =>#t79;
+  core::Set<core::num*>* set83 = block {
+    final core::Set<core::num*>* #t80 = col::LinkedHashSet::•<core::num*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t80.{core::Set::addAll}{Invariant}(listInt){(core::Iterable<core::num*>*) →* void};
+    else
+      #t80.{core::Set::add}{Invariant}(3.14){(core::num*) →* core::bool*};
+    #t80.{core::Set::add}{Invariant}(null){(core::num*) →* core::bool*};
+  } =>#t80;
+  core::Map<core::String*, core::num*>* map83 = block {
+    final core::Map<core::String*, core::num*>* #t81 = <core::String*, core::num*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      for (final core::MapEntry<core::String*, core::num*>* #t82 in mapToInt.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::num*>>})
+        #t81.{core::Map::[]=}{Invariant}(#t82.{core::MapEntry::key}{core::String*}, #t82.{core::MapEntry::value}{core::num*}){(core::String*, core::num*) →* void};
+    else
+      #t81.{core::Map::[]=}{Invariant}("bar", 3.14){(core::String*, core::num*) →* void};
+    #t81.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::num*) →* void};
+  } =>#t81;
+  core::List<core::int*>* list90 = block {
+    final core::List<core::int*>* #t83 = <core::int*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t83.{core::List::add}{Invariant}(dynVar as{TypeError,ForDynamic} core::int*){(core::int*) →* void};
+  } =>#t83;
+  core::Set<core::int*>* set90 = block {
+    final core::Set<core::int*>* #t84 = col::LinkedHashSet::•<core::int*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t84.{core::Set::add}{Invariant}(dynVar as{TypeError,ForDynamic} core::int*){(core::int*) →* core::bool*};
+    #t84.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t84;
+  core::Map<core::String*, core::int*>* map90 = block {
+    final core::Map<core::String*, core::int*>* #t85 = <core::String*, core::int*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t85.{core::Map::[]=}{Invariant}("bar", dynVar as{TypeError,ForDynamic} core::int*){(core::String*, core::int*) →* void};
+    #t85.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t85;
+  core::List<core::int*>* list91 = block {
+    final core::List<core::int*>* #t86 = <core::int*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      for (final dynamic #t87 in dynVar as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+        final core::int* #t88 = #t87 as{TypeError} core::int*;
+        #t86.{core::List::add}{Invariant}(#t88){(core::int*) →* void};
+      }
+  } =>#t86;
+  core::Set<core::int*>* set91 = block {
+    final core::Set<core::int*>* #t89 = col::LinkedHashSet::•<core::int*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      for (final dynamic #t90 in dynVar as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+        final core::int* #t91 = #t90 as{TypeError} core::int*;
+        #t89.{core::Set::add}{Invariant}(#t91){(core::int*) →* core::bool*};
+      }
+    #t89.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t89;
+  core::Map<core::String*, core::int*>* map91 = block {
+    final core::Map<core::String*, core::int*>* #t92 = <core::String*, core::int*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      for (final core::MapEntry<dynamic, dynamic>* #t93 in (dynVar as{TypeError,ForDynamic} core::Map<dynamic, dynamic>*).{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>}) {
+        final core::String* #t94 = #t93.{core::MapEntry::key}{dynamic} as{TypeError} core::String*;
+        final core::int* #t95 = #t93.{core::MapEntry::value}{dynamic} as{TypeError} core::int*;
+        #t92.{core::Map::[]=}{Invariant}(#t94, #t95){(core::String*, core::int*) →* void};
+      }
+    #t92.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t92;
+  core::List<core::int*>* list100 = block {
+    final core::List<core::int*>* #t96 = <core::int*>[];
+    if(dynVar as{TypeError,ForDynamic} core::bool*)
+      #t96.{core::List::add}{Invariant}(42){(core::int*) →* void};
+  } =>#t96;
+  core::Set<core::int*>* set100 = block {
+    final core::Set<core::int*>* #t97 = col::LinkedHashSet::•<core::int*>();
+    if(dynVar as{TypeError,ForDynamic} core::bool*)
+      #t97.{core::Set::add}{Invariant}(42){(core::int*) →* core::bool*};
+  } =>#t97;
+  core::Map<core::int*, core::int*>* map100 = block {
+    final core::Map<core::int*, core::int*>* #t98 = <core::int*, core::int*>{};
+    if(dynVar as{TypeError,ForDynamic} core::bool*)
+      #t98.{core::Map::[]=}{Invariant}(42, 42){(core::int*, core::int*) →* void};
+  } =>#t98;
+}
+static method testIfElementErrors(core::Map<core::int*, core::int*>* map) → dynamic {
+  block {
+    final core::List<core::int*>* #t99 = <core::int*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t99.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:87:28: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <int>[if (oracle(\"foo\")) \"bar\"];
+                           ^" in "bar" as{TypeError} core::int*){(core::int*) →* void};
+  } =>#t99;
+  block {
+    final core::Set<core::int*>* #t100 = col::LinkedHashSet::•<core::int*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t100.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:88:28: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <int>{if (oracle(\"foo\")) \"bar\", null};
+                           ^" in "bar" as{TypeError} core::int*){(core::int*) →* core::bool*};
+    #t100.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t100;
+  block {
+    final core::Map<core::String*, core::int*>* #t101 = <core::String*, core::int*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t101.{core::Map::[]=}{Invariant}("bar", invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:89:43: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <String, int>{if (oracle(\"foo\")) \"bar\": \"bar\", \"baz\": null};
+                                          ^" in "bar" as{TypeError} core::int*){(core::String*, core::int*) →* void};
+    #t101.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t101;
+  block {
+    final core::List<core::int*>* #t102 = <core::int*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t102.{core::List::addAll}{Invariant}(<core::int*>[invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:90:32: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <int>[if (oracle(\"foo\")) ...[\"bar\"]];
+                               ^" in "bar" as{TypeError} core::int*]){(core::Iterable<core::int*>*) →* void};
+  } =>#t102;
+  block {
+    final core::Set<core::int*>* #t103 = col::LinkedHashSet::•<core::int*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t103.{core::Set::addAll}{Invariant}(<core::int*>[invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:91:32: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <int>{if (oracle(\"foo\")) ...[\"bar\"], null};
+                               ^" in "bar" as{TypeError} core::int*]){(core::Iterable<core::int*>*) →* void};
+    #t103.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t103;
+  block {
+    final core::Map<core::String*, core::int*>* #t104 = <core::String*, core::int*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      for (final core::MapEntry<core::String*, core::int*>* #t105 in <core::String*, core::int*>{"bar": invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:92:47: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <String, int>{if (oracle(\"foo\")) ...{\"bar\": \"bar\"}, \"baz\": null};
+                                              ^" in "bar" as{TypeError} core::int*}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>})
+        #t104.{core::Map::[]=}{Invariant}(#t105.{core::MapEntry::key}{core::String*}, #t105.{core::MapEntry::value}{core::int*}){(core::String*, core::int*) →* void};
+    #t104.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t104;
+  block {
+    final core::List<core::int*>* #t106 = <core::int*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t106.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:93:31: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+ - 'Map' is from 'dart:core'.
+  <int>[if (oracle(\"foo\")) ...map];
+                              ^"){(core::int*) →* void};
+  } =>#t106;
+  block {
+    final core::Set<core::int*>* #t107 = col::LinkedHashSet::•<core::int*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t107.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:94:31: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+ - 'Map' is from 'dart:core'.
+  <int>{if (oracle(\"foo\")) ...map, null};
+                              ^"){(core::int*) →* core::bool*};
+    #t107.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t107;
+  <core::String*, core::int*>{invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:95:39: Error: Unexpected type 'List<String>' of a map spread entry.  Expected 'dynamic' or a Map.
+ - 'List' is from 'dart:core'.
+  <String, int>{if (oracle(\"foo\")) ...[\"bar\"], \"baz\": null};
+                                      ^": null, invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:95:39: Error: Unexpected type 'List<String>' of a map spread entry.  Expected 'dynamic' or a Map.
+ - 'List' is from 'dart:core'.
+  <String, int>{if (oracle(\"foo\")) ...[\"bar\"], \"baz\": null};
+                                      ^": null};
+  block {
+    final core::List<core::String*>* #t108 = <core::String*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t108.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:96:31: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  <String>[if (oracle(\"foo\")) 42 else 3.14];
+                              ^" in 42 as{TypeError} core::String*){(core::String*) →* void};
+    else
+      #t108.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:96:39: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+  <String>[if (oracle(\"foo\")) 42 else 3.14];
+                                      ^" in 3.14 as{TypeError} core::String*){(core::String*) →* void};
+  } =>#t108;
+  block {
+    final core::Set<core::String*>* #t109 = col::LinkedHashSet::•<core::String*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t109.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:97:31: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  <String>{if (oracle(\"foo\")) 42 else 3.14, null};
+                              ^" in 42 as{TypeError} core::String*){(core::String*) →* core::bool*};
+    else
+      #t109.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:97:39: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+  <String>{if (oracle(\"foo\")) 42 else 3.14, null};
+                                      ^" in 3.14 as{TypeError} core::String*){(core::String*) →* core::bool*};
+    #t109.{core::Set::add}{Invariant}(null){(core::String*) →* core::bool*};
+  } =>#t109;
+  block {
+    final core::Map<core::String*, core::String*>* #t110 = <core::String*, core::String*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t110.{core::Map::[]=}{Invariant}("bar", invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:98:46: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  <String, String>{if (oracle(\"foo\")) \"bar\": 42 else \"baz\": 3.14, \"baz\": null};
+                                             ^" in 42 as{TypeError} core::String*){(core::String*, core::String*) →* void};
+    else
+      #t110.{core::Map::[]=}{Invariant}("baz", invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:98:61: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+  <String, String>{if (oracle(\"foo\")) \"bar\": 42 else \"baz\": 3.14, \"baz\": null};
+                                                            ^" in 3.14 as{TypeError} core::String*){(core::String*, core::String*) →* void};
+    #t110.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::String*) →* void};
+  } =>#t110;
+  block {
+    final core::List<core::int*>* #t111 = <core::int*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t111.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:99:31: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+ - 'Map' is from 'dart:core'.
+  <int>[if (oracle(\"foo\")) ...map else 42];
+                              ^"){(core::int*) →* void};
+    else
+      #t111.{core::List::add}{Invariant}(42){(core::int*) →* void};
+  } =>#t111;
+  block {
+    final core::Set<core::int*>* #t112 = col::LinkedHashSet::•<core::int*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t112.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:100:31: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+ - 'Map' is from 'dart:core'.
+  <int>{if (oracle(\"foo\")) ...map else 42, null};
+                              ^"){(core::int*) →* core::bool*};
+    else
+      #t112.{core::Set::add}{Invariant}(42){(core::int*) →* core::bool*};
+    #t112.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t112;
+  <core::String*, core::int*>{invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:101:39: Error: Unexpected type 'List<int>' of a map spread entry.  Expected 'dynamic' or a Map.
+ - 'List' is from 'dart:core'.
+  <String, int>{if (oracle(\"foo\")) ...[42] else \"bar\": 42, \"baz\": null};
+                                      ^": null, invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:101:39: Error: Unexpected type 'List<int>' of a map spread entry.  Expected 'dynamic' or a Map.
+ - 'List' is from 'dart:core'.
+  <String, int>{if (oracle(\"foo\")) ...[42] else \"bar\": 42, \"baz\": null};
+                                      ^": null};
+  block {
+    final core::List<core::int*>* #t113 = <core::int*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t113.{core::List::add}{Invariant}(42){(core::int*) →* void};
+    else
+      #t113.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:102:39: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+ - 'Map' is from 'dart:core'.
+  <int>[if (oracle(\"foo\")) 42 else ...map];
+                                      ^"){(core::int*) →* void};
+  } =>#t113;
+  block {
+    final core::Set<core::int*>* #t114 = col::LinkedHashSet::•<core::int*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t114.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:103:31: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+ - 'Map' is from 'dart:core'.
+  <int>{if (oracle(\"foo\")) ...map else 42, null};
+                              ^"){(core::int*) →* core::bool*};
+    else
+      #t114.{core::Set::add}{Invariant}(42){(core::int*) →* core::bool*};
+    #t114.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t114;
+  <core::String*, core::int*>{invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:104:54: Error: Unexpected type 'List<int>' of a map spread entry.  Expected 'dynamic' or a Map.
+ - 'List' is from 'dart:core'.
+  <String, int>{if (oracle(\"foo\")) \"bar\": 42 else ...[42], \"baz\": null};
+                                                     ^": null, invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:104:54: Error: Unexpected type 'List<int>' of a map spread entry.  Expected 'dynamic' or a Map.
+ - 'List' is from 'dart:core'.
+  <String, int>{if (oracle(\"foo\")) \"bar\": 42 else ...[42], \"baz\": null};
+                                                     ^": null};
+  core::Set<dynamic>* set10 = invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:106:24: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+  Set<dynamic> set10 = {if (oracle(\"foo\")) 42 else \"bar\": 3.14};
+                       ^";
+  core::Map<dynamic, dynamic>* map10 = <dynamic, dynamic>{invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:107:53: Error: Expected ':' after this.
+  Map<dynamic, dynamic> map10 = {if (oracle(\"foo\")) 42 else \"bar\": 3.14};
+                                                    ^": null};
+  core::Set<dynamic>* set11 = invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:108:24: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+  Set<dynamic> set11 = {if (oracle(\"foo\")) \"bar\": 3.14 else 42};
+                       ^";
+  core::Map<dynamic, dynamic>* map11 = <dynamic, dynamic>{invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:109:70: Error: Expected ':' after this.
+  Map<dynamic, dynamic> map11 = {if (oracle(\"foo\")) \"bar\": 3.14 else 42};
+                                                                     ^": null};
+  core::Map<invalid-type, Null>* map12 = <invalid-type, Null>{invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:110:35: Error: Expected ':' after this.
+  var map12 = {if (oracle(\"foo\")) 42 else \"bar\": 3.14};
+                                  ^": null};
+  core::Map<invalid-type, Null>* map13 = <invalid-type, Null>{invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:111:52: Error: Expected ':' after this.
+  var map13 = {if (oracle(\"foo\")) \"bar\": 3.14 else 42};
+                                                   ^": null};
+  core::List<core::int*>* list20 = block {
+    final core::List<core::int*>* #t115 = <core::int*>[];
+    if(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:112:27: Error: A value of type 'int' can't be assigned to a variable of type 'bool'.
+  List<int> list20 = [if (42) 42];
+                          ^" in 42 as{TypeError} core::bool*)
+      #t115.{core::List::add}{Invariant}(42){(core::int*) →* void};
+  } =>#t115;
+  core::Set<core::int*>* set20 = block {
+    final core::Set<core::int*>* #t116 = col::LinkedHashSet::•<core::int*>();
+    if(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:113:25: Error: A value of type 'int' can't be assigned to a variable of type 'bool'.
+  Set<int> set20 = {if (42) 42};
+                        ^" in 42 as{TypeError} core::bool*)
+      #t116.{core::Set::add}{Invariant}(42){(core::int*) →* core::bool*};
+  } =>#t116;
+  core::Map<core::int*, core::int*>* map30 = block {
+    final core::Map<core::int*, core::int*>* #t117 = <core::int*, core::int*>{};
+    if(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:114:30: Error: A value of type 'int' can't be assigned to a variable of type 'bool'.
+  Map<int, int> map30 = {if (42) 42: 42};
+                             ^" in 42 as{TypeError} core::bool*)
+      #t117.{core::Map::[]=}{Invariant}(42, 42){(core::int*, core::int*) →* void};
+  } =>#t117;
+  core::List<core::String*>* list40 = block {
+    final core::List<core::String*>* #t118 = <core::String*>[];
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t118.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:115:53: Error: A value of type 'bool' can't be assigned to a variable of type 'String'.
+  List<String> list40 = <String>[if (oracle(\"foo\")) true else 42];
+                                                    ^" in true as{TypeError} core::String*){(core::String*) →* void};
+    else
+      #t118.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:115:63: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  List<String> list40 = <String>[if (oracle(\"foo\")) true else 42];
+                                                              ^" in 42 as{TypeError} core::String*){(core::String*) →* void};
+  } =>#t118;
+  core::Set<core::String*>* set40 = block {
+    final core::Set<core::String*>* #t119 = col::LinkedHashSet::•<core::String*>();
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t119.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:116:51: Error: A value of type 'bool' can't be assigned to a variable of type 'String'.
+  Set<String> set40 = <String>{if (oracle(\"foo\")) true else 42};
+                                                  ^" in true as{TypeError} core::String*){(core::String*) →* core::bool*};
+    else
+      #t119.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:116:61: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  Set<String> set40 = <String>{if (oracle(\"foo\")) true else 42};
+                                                            ^" in 42 as{TypeError} core::String*){(core::String*) →* core::bool*};
+  } =>#t119;
+  core::Map<core::String*, core::int*>* map40 = block {
+    final core::Map<core::String*, core::int*>* #t120 = <core::String*, core::int*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t120.{core::Map::[]=}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:117:61: Error: A value of type 'bool' can't be assigned to a variable of type 'String'.
+  Map<String, int> map40 = <String, int>{if (oracle(\"foo\")) true: 42 else 42: 42};
+                                                            ^" in true as{TypeError} core::String*, 42){(core::String*, core::int*) →* void};
+    else
+      #t120.{core::Map::[]=}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:117:75: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  Map<String, int> map40 = <String, int>{if (oracle(\"foo\")) true: 42 else 42: 42};
+                                                                          ^" in 42 as{TypeError} core::String*, 42){(core::String*, core::int*) →* void};
+  } =>#t120;
+  core::Map<core::int*, core::String*>* map41 = block {
+    final core::Map<core::int*, core::String*>* #t121 = <core::int*, core::String*>{};
+    if(self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*)
+      #t121.{core::Map::[]=}{Invariant}(42, invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:118:65: Error: A value of type 'bool' can't be assigned to a variable of type 'String'.
+  Map<int, String> map41 = <int, String>{if (oracle(\"foo\")) 42: true else 42: 42};
+                                                                ^" in true as{TypeError} core::String*){(core::int*, core::String*) →* void};
+    else
+      #t121.{core::Map::[]=}{Invariant}(42, invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:118:79: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  Map<int, String> map41 = <int, String>{if (oracle(\"foo\")) 42: true else 42: 42};
+                                                                              ^" in 42 as{TypeError} core::String*){(core::int*, core::String*) →* void};
+  } =>#t121;
+}
+static method testForElement(dynamic dynVar, core::List<core::int*>* listInt, core::List<core::double*>* listDouble, core::int* index, core::Map<core::String*, core::int*>* mapStringInt, core::Map<core::String*, core::double*>* mapStringDouble) → dynamic {
+  core::List<core::int*>* list10 = block {
+    final core::List<core::int*>* #t122 = <core::int*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t122.{core::List::add}{Invariant}(42){(core::int*) →* void};
+  } =>#t122;
+  core::Set<core::int*>* set10 = block {
+    final core::Set<core::int*>* #t123 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t123.{core::Set::add}{Invariant}(42){(core::int*) →* core::bool*};
+    #t123.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t123;
+  core::Map<core::String*, core::int*>* map10 = block {
+    final core::Map<core::String*, core::int*>* #t124 = <core::String*, core::int*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t124.{core::Map::[]=}{Invariant}("bar", 42){(core::String*, core::int*) →* void};
+    #t124.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t124;
+  core::List<dynamic>* list11 = block {
+    final core::List<dynamic>* #t125 = <dynamic>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t125.{core::List::add}{Invariant}(dynVar){(dynamic) →* void};
+  } =>#t125;
+  core::Set<dynamic>* set11 = block {
+    final core::Set<dynamic>* #t126 = col::LinkedHashSet::•<dynamic>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t126.{core::Set::add}{Invariant}(dynVar){(dynamic) →* core::bool*};
+    #t126.{core::Set::add}{Invariant}(null){(dynamic) →* core::bool*};
+  } =>#t126;
+  core::Map<core::String*, dynamic>* map11 = block {
+    final core::Map<core::String*, dynamic>* #t127 = <core::String*, dynamic>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t127.{core::Map::[]=}{Invariant}("bar", dynVar){(core::String*, dynamic) →* void};
+    #t127.{core::Map::[]=}{Invariant}("baz", null){(core::String*, dynamic) →* void};
+  } =>#t127;
+  core::List<core::List<core::int*>*>* list12 = block {
+    final core::List<core::List<core::int*>*>* #t128 = <core::List<core::int*>*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t128.{core::List::add}{Invariant}(<core::int*>[42]){(core::List<core::int*>*) →* void};
+  } =>#t128;
+  core::Set<core::List<core::int*>*>* set12 = block {
+    final core::Set<core::List<core::int*>*>* #t129 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t129.{core::Set::add}{Invariant}(<core::int*>[42]){(core::List<core::int*>*) →* core::bool*};
+    #t129.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t129;
+  core::Map<core::String*, core::List<core::int*>*>* map12 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t130 = <core::String*, core::List<core::int*>*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t130.{core::Map::[]=}{Invariant}("bar", <core::int*>[42]){(core::String*, core::List<core::int*>*) →* void};
+    #t130.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t130;
+  core::List<core::int*>* list20 = block {
+    final core::List<core::int*>* #t131 = <core::int*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t131.{core::List::addAll}{Invariant}(<core::int*>[42]){(core::Iterable<core::int*>*) →* void};
+  } =>#t131;
+  core::Set<core::int*>* set20 = block {
+    final core::Set<core::int*>* #t132 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t132.{core::Set::addAll}{Invariant}(<core::int*>[42]){(core::Iterable<core::int*>*) →* void};
+    #t132.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t132;
+  core::Map<core::String*, core::int*>* map20 = block {
+    final core::Map<core::String*, core::int*>* #t133 = <core::String*, core::int*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      for (final core::MapEntry<core::String*, core::int*>* #t134 in <core::String*, core::int*>{"bar": 42}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>})
+        #t133.{core::Map::[]=}{Invariant}(#t134.{core::MapEntry::key}{core::String*}, #t134.{core::MapEntry::value}{core::int*}){(core::String*, core::int*) →* void};
+    #t133.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t133;
+  core::List<dynamic>* list21 = block {
+    final core::List<dynamic>* #t135 = <dynamic>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t135.{core::List::addAll}{Invariant}(<dynamic>[dynVar]){(core::Iterable<dynamic>*) →* void};
+  } =>#t135;
+  core::Set<dynamic>* set21 = block {
+    final core::Set<dynamic>* #t136 = col::LinkedHashSet::•<dynamic>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t136.{core::Set::addAll}{Invariant}(<dynamic>[dynVar]){(core::Iterable<dynamic>*) →* void};
+    #t136.{core::Set::add}{Invariant}(null){(dynamic) →* core::bool*};
+  } =>#t136;
+  core::Map<core::String*, dynamic>* map21 = block {
+    final core::Map<core::String*, dynamic>* #t137 = <core::String*, dynamic>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      for (final core::MapEntry<core::String*, dynamic>* #t138 in <core::String*, dynamic>{"bar": dynVar}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, dynamic>>})
+        #t137.{core::Map::[]=}{Invariant}(#t138.{core::MapEntry::key}{core::String*}, #t138.{core::MapEntry::value}{dynamic}){(core::String*, dynamic) →* void};
+    #t137.{core::Map::[]=}{Invariant}("baz", null){(core::String*, dynamic) →* void};
+  } =>#t137;
+  core::List<core::List<core::int*>*>* list22 = block {
+    final core::List<core::List<core::int*>*>* #t139 = <core::List<core::int*>*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t139.{core::List::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[42]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+  } =>#t139;
+  core::Set<core::List<core::int*>*>* set22 = block {
+    final core::Set<core::List<core::int*>*>* #t140 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t140.{core::Set::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[42]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+    #t140.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t140;
+  core::Map<core::String*, core::List<core::int*>*>* map22 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t141 = <core::String*, core::List<core::int*>*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      for (final core::MapEntry<core::String*, core::List<core::int*>*>* #t142 in <core::String*, core::List<core::int*>*>{"bar": <core::int*>[42]}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::List<core::int*>*>>})
+        #t141.{core::Map::[]=}{Invariant}(#t142.{core::MapEntry::key}{core::String*}, #t142.{core::MapEntry::value}{core::List<core::int*>*}){(core::String*, core::List<core::int*>*) →* void};
+    #t141.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t141;
+  core::List<core::int*>* list30 = block {
+    final core::List<core::int*>* #t143 = <core::int*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t143.{core::List::addAll}{Invariant}(<core::int*>[42]){(core::Iterable<core::int*>*) →* void};
+  } =>#t143;
+  core::Set<core::int*>* set30 = block {
+    final core::Set<core::int*>* #t144 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t144.{core::Set::addAll}{Invariant}(<core::int*>[42]){(core::Iterable<core::int*>*) →* void};
+    #t144.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t144;
+  core::Map<core::String*, core::int*>* map30 = block {
+    final core::Map<core::String*, core::int*>* #t145 = <core::String*, core::int*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        for (final core::MapEntry<core::String*, core::int*>* #t146 in <core::String*, core::int*>{"bar": 42}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>})
+          #t145.{core::Map::[]=}{Invariant}(#t146.{core::MapEntry::key}{core::String*}, #t146.{core::MapEntry::value}{core::int*}){(core::String*, core::int*) →* void};
+    #t145.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t145;
+  core::List<dynamic>* list31 = block {
+    final core::List<dynamic>* #t147 = <dynamic>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t147.{core::List::addAll}{Invariant}(<dynamic>[dynVar]){(core::Iterable<dynamic>*) →* void};
+  } =>#t147;
+  core::Set<dynamic>* set31 = block {
+    final core::Set<dynamic>* #t148 = col::LinkedHashSet::•<dynamic>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t148.{core::Set::addAll}{Invariant}(<dynamic>[dynVar]){(core::Iterable<dynamic>*) →* void};
+    #t148.{core::Set::add}{Invariant}(null){(dynamic) →* core::bool*};
+  } =>#t148;
+  core::Map<core::String*, dynamic>* map31 = block {
+    final core::Map<core::String*, dynamic>* #t149 = <core::String*, dynamic>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        for (final core::MapEntry<core::String*, dynamic>* #t150 in <core::String*, dynamic>{"bar": dynVar}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, dynamic>>})
+          #t149.{core::Map::[]=}{Invariant}(#t150.{core::MapEntry::key}{core::String*}, #t150.{core::MapEntry::value}{dynamic}){(core::String*, dynamic) →* void};
+    #t149.{core::Map::[]=}{Invariant}("baz", null){(core::String*, dynamic) →* void};
+  } =>#t149;
+  core::List<core::List<core::int*>*>* list33 = block {
+    final core::List<core::List<core::int*>*>* #t151 = <core::List<core::int*>*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t151.{core::List::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[42]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+  } =>#t151;
+  core::Set<core::List<core::int*>*>* set33 = block {
+    final core::Set<core::List<core::int*>*>* #t152 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t152.{core::Set::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[42]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+    #t152.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t152;
+  core::Map<core::String*, core::List<core::int*>*>* map33 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t153 = <core::String*, core::List<core::int*>*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        for (final core::MapEntry<core::String*, core::List<core::int*>*>* #t154 in <core::String*, core::List<core::int*>*>{"bar": <core::int*>[42]}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::List<core::int*>*>>})
+          #t153.{core::Map::[]=}{Invariant}(#t154.{core::MapEntry::key}{core::String*}, #t154.{core::MapEntry::value}{core::List<core::int*>*}){(core::String*, core::List<core::int*>*) →* void};
+    #t153.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t153;
+  core::List<core::List<core::int*>*>* list40 = block {
+    final core::List<core::List<core::int*>*>* #t155 = <core::List<core::int*>*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t155.{core::List::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+  } =>#t155;
+  core::Set<core::List<core::int*>*>* set40 = block {
+    final core::Set<core::List<core::int*>*>* #t156 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t156.{core::Set::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+    #t156.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t156;
+  core::Map<core::String*, core::List<core::int*>*>* map40 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t157 = <core::String*, core::List<core::int*>*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      for (final core::MapEntry<core::String*, core::List<core::int*>*>* #t158 in <core::String*, core::List<core::int*>*>{"bar": <core::int*>[]}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::List<core::int*>*>>})
+        #t157.{core::Map::[]=}{Invariant}(#t158.{core::MapEntry::key}{core::String*}, #t158.{core::MapEntry::value}{core::List<core::int*>*}){(core::String*, core::List<core::int*>*) →* void};
+    #t157.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t157;
+  core::List<core::List<core::int*>*>* list41 = block {
+    final core::List<core::List<core::int*>*>* #t159 = <core::List<core::int*>*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t159.{core::List::addAll}{Invariant}( block {
+        final core::Set<core::List<core::int*>*>* #t160 = col::LinkedHashSet::•<core::List<core::int*>*>();
+        #t160.{core::Set::add}{Invariant}(<core::int*>[]){(core::List<core::int*>*) →* core::bool*};
+      } =>#t160){(core::Iterable<core::List<core::int*>*>*) →* void};
+  } =>#t159;
+  core::Set<core::List<core::int*>*>* set41 = block {
+    final core::Set<core::List<core::int*>*>* #t161 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t161.{core::Set::addAll}{Invariant}( block {
+        final core::Set<core::List<core::int*>*>* #t162 = col::LinkedHashSet::•<core::List<core::int*>*>();
+        #t162.{core::Set::add}{Invariant}(<core::int*>[]){(core::List<core::int*>*) →* core::bool*};
+      } =>#t162){(core::Iterable<core::List<core::int*>*>*) →* void};
+    #t161.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t161;
+  core::List<core::List<core::int*>*>* list42 = block {
+    final core::List<core::List<core::int*>*>* #t163 = <core::List<core::int*>*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t163.{core::List::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+  } =>#t163;
+  core::Set<core::List<core::int*>*>* set42 = block {
+    final core::Set<core::List<core::int*>*>* #t164 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t164.{core::Set::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+    #t164.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t164;
+  core::Map<core::String*, core::List<core::int*>*>* map42 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t165 = <core::String*, core::List<core::int*>*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        for (final core::MapEntry<core::String*, core::List<core::int*>*>* #t166 in <core::String*, core::List<core::int*>*>{"bar": <core::int*>[]}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::List<core::int*>*>>})
+          #t165.{core::Map::[]=}{Invariant}(#t166.{core::MapEntry::key}{core::String*}, #t166.{core::MapEntry::value}{core::List<core::int*>*}){(core::String*, core::List<core::int*>*) →* void};
+    #t165.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t165;
+  core::List<core::int*>* list50 = block {
+    final core::List<core::int*>* #t167 = <core::int*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t167.{core::List::addAll}{Invariant}(<core::int*>[]){(core::Iterable<core::int*>*) →* void};
+  } =>#t167;
+  core::Set<core::int*>* set50 = block {
+    final core::Set<core::int*>* #t168 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t168.{core::Set::addAll}{Invariant}(<core::int*>[]){(core::Iterable<core::int*>*) →* void};
+    #t168.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t168;
+  core::Map<core::String*, core::int*>* map50 = block {
+    final core::Map<core::String*, core::int*>* #t169 = <core::String*, core::int*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      for (final core::MapEntry<core::String*, core::int*>* #t170 in <core::String*, core::int*>{}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>})
+        #t169.{core::Map::[]=}{Invariant}(#t170.{core::MapEntry::key}{core::String*}, #t170.{core::MapEntry::value}{core::int*}){(core::String*, core::int*) →* void};
+    #t169.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t169;
+  core::List<core::int*>* list51 = block {
+    final core::List<core::int*>* #t171 = <core::int*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t171.{core::List::addAll}{Invariant}( block {
+        final core::Set<core::int*>* #t172 = col::LinkedHashSet::•<core::int*>();
+      } =>#t172){(core::Iterable<core::int*>*) →* void};
+  } =>#t171;
+  core::Set<core::int*>* set51 = block {
+    final core::Set<core::int*>* #t173 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t173.{core::Set::addAll}{Invariant}( block {
+        final core::Set<core::int*>* #t174 = col::LinkedHashSet::•<core::int*>();
+      } =>#t174){(core::Iterable<core::int*>*) →* void};
+    #t173.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t173;
+  core::List<core::int*>* list52 = block {
+    final core::List<core::int*>* #t175 = <core::int*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t175.{core::List::addAll}{Invariant}(<core::int*>[]){(core::Iterable<core::int*>*) →* void};
+  } =>#t175;
+  core::Set<core::int*>* set52 = block {
+    final core::Set<core::int*>* #t176 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t176.{core::Set::addAll}{Invariant}(<core::int*>[]){(core::Iterable<core::int*>*) →* void};
+    #t176.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t176;
+  core::List<core::List<core::int*>*>* list60 = block {
+    final core::List<core::List<core::int*>*>* #t177 = <core::List<core::int*>*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t177.{core::List::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+  } =>#t177;
+  core::Set<core::List<core::int*>*>* set60 = block {
+    final core::Set<core::List<core::int*>*>* #t178 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t178.{core::Set::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+    #t178.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t178;
+  core::Map<core::String*, core::List<core::int*>*>* map60 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t179 = <core::String*, core::List<core::int*>*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      for (final core::MapEntry<core::String*, core::List<core::int*>*>* #t180 in <core::String*, core::List<core::int*>*>{"bar": <core::int*>[]}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::List<core::int*>*>>})
+        #t179.{core::Map::[]=}{Invariant}(#t180.{core::MapEntry::key}{core::String*}, #t180.{core::MapEntry::value}{core::List<core::int*>*}){(core::String*, core::List<core::int*>*) →* void};
+    #t179.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t179;
+  core::List<core::List<core::int*>*>* list61 = block {
+    final core::List<core::List<core::int*>*>* #t181 = <core::List<core::int*>*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t181.{core::List::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+  } =>#t181;
+  core::Set<core::List<core::int*>*>* set61 = block {
+    final core::Set<core::List<core::int*>*>* #t182 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t182.{core::Set::addAll}{Invariant}(<core::List<core::int*>*>[<core::int*>[]]){(core::Iterable<core::List<core::int*>*>*) →* void};
+    #t182.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t182;
+  core::Map<core::String*, core::List<core::int*>*>* map61 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t183 = <core::String*, core::List<core::int*>*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        for (final core::MapEntry<core::String*, core::List<core::int*>*>* #t184 in <core::String*, core::List<core::int*>*>{"bar": <core::int*>[]}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::List<core::int*>*>>})
+          #t183.{core::Map::[]=}{Invariant}(#t184.{core::MapEntry::key}{core::String*}, #t184.{core::MapEntry::value}{core::List<core::int*>*}){(core::String*, core::List<core::int*>*) →* void};
+    #t183.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t183;
+  core::List<core::List<core::int*>*>* list70 = block {
+    final core::List<core::List<core::int*>*>* #t185 = <core::List<core::int*>*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t185.{core::List::add}{Invariant}(<core::int*>[]){(core::List<core::int*>*) →* void};
+  } =>#t185;
+  core::Set<core::List<core::int*>*>* set70 = block {
+    final core::Set<core::List<core::int*>*>* #t186 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t186.{core::Set::add}{Invariant}(<core::int*>[]){(core::List<core::int*>*) →* core::bool*};
+    #t186.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t186;
+  core::Map<core::String*, core::List<core::int*>*>* map70 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t187 = <core::String*, core::List<core::int*>*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t187.{core::Map::[]=}{Invariant}("bar", <core::int*>[]){(core::String*, core::List<core::int*>*) →* void};
+    #t187.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t187;
+  core::List<core::List<core::int*>*>* list71 = block {
+    final core::List<core::List<core::int*>*>* #t188 = <core::List<core::int*>*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t188.{core::List::add}{Invariant}(<core::int*>[]){(core::List<core::int*>*) →* void};
+  } =>#t188;
+  core::Set<core::List<core::int*>*>* set71 = block {
+    final core::Set<core::List<core::int*>*>* #t189 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t189.{core::Set::add}{Invariant}(<core::int*>[]){(core::List<core::int*>*) →* core::bool*};
+    #t189.{core::Set::add}{Invariant}(null){(core::List<core::int*>*) →* core::bool*};
+  } =>#t189;
+  core::Map<core::String*, core::List<core::int*>*>* map71 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t190 = <core::String*, core::List<core::int*>*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t190.{core::Map::[]=}{Invariant}("bar", <core::int*>[]){(core::String*, core::List<core::int*>*) →* void};
+    #t190.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t190;
+  core::List<core::num*>* list80 = block {
+    final core::List<core::num*>* #t191 = <core::num*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t191.{core::List::add}{Invariant}(42){(core::num*) →* void};
+      else
+        #t191.{core::List::add}{Invariant}(3.14){(core::num*) →* void};
+  } =>#t191;
+  core::Set<core::num*>* set80 = block {
+    final core::Set<core::num*>* #t192 = col::LinkedHashSet::•<core::num*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t192.{core::Set::add}{Invariant}(42){(core::num*) →* core::bool*};
+      else
+        #t192.{core::Set::add}{Invariant}(3.14){(core::num*) →* core::bool*};
+    #t192.{core::Set::add}{Invariant}(null){(core::num*) →* core::bool*};
+  } =>#t192;
+  core::Map<core::String*, core::num*>* map80 = block {
+    final core::Map<core::String*, core::num*>* #t193 = <core::String*, core::num*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t193.{core::Map::[]=}{Invariant}("bar", 42){(core::String*, core::num*) →* void};
+      else
+        #t193.{core::Map::[]=}{Invariant}("bar", 3.14){(core::String*, core::num*) →* void};
+    #t193.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::num*) →* void};
+  } =>#t193;
+  core::List<core::num*>* list81 = block {
+    final core::List<core::num*>* #t194 = <core::num*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t194.{core::List::addAll}{Invariant}(listInt){(core::Iterable<core::num*>*) →* void};
+      else
+        #t194.{core::List::addAll}{Invariant}(listDouble){(core::Iterable<core::num*>*) →* void};
+  } =>#t194;
+  core::Set<core::num*>* set81 = block {
+    final core::Set<core::num*>* #t195 = col::LinkedHashSet::•<core::num*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t195.{core::Set::addAll}{Invariant}(listInt){(core::Iterable<core::num*>*) →* void};
+      else
+        #t195.{core::Set::addAll}{Invariant}(listDouble){(core::Iterable<core::num*>*) →* void};
+    #t195.{core::Set::add}{Invariant}(null){(core::num*) →* core::bool*};
+  } =>#t195;
+  core::Map<core::String*, core::num*>* map81 = block {
+    final core::Map<core::String*, core::num*>* #t196 = <core::String*, core::num*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        for (final core::MapEntry<core::String*, core::num*>* #t197 in mapStringInt.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::num*>>})
+          #t196.{core::Map::[]=}{Invariant}(#t197.{core::MapEntry::key}{core::String*}, #t197.{core::MapEntry::value}{core::num*}){(core::String*, core::num*) →* void};
+      else
+        for (final core::MapEntry<core::String*, core::num*>* #t198 in mapStringDouble.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::num*>>})
+          #t196.{core::Map::[]=}{Invariant}(#t198.{core::MapEntry::key}{core::String*}, #t198.{core::MapEntry::value}{core::num*}){(core::String*, core::num*) →* void};
+    #t196.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::num*) →* void};
+  } =>#t196;
+  core::List<dynamic>* list82 = block {
+    final core::List<dynamic>* #t199 = <dynamic>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t199.{core::List::addAll}{Invariant}(listInt){(core::Iterable<dynamic>*) →* void};
+      else
+        #t199.{core::List::addAll}{Invariant}(dynVar as{TypeError,ForDynamic} core::Iterable<dynamic>*){(core::Iterable<dynamic>*) →* void};
+  } =>#t199;
+  core::Set<dynamic>* set82 = block {
+    final core::Set<dynamic>* #t200 = col::LinkedHashSet::•<dynamic>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t200.{core::Set::addAll}{Invariant}(listInt){(core::Iterable<dynamic>*) →* void};
+      else
+        #t200.{core::Set::addAll}{Invariant}(dynVar as{TypeError,ForDynamic} core::Iterable<dynamic>*){(core::Iterable<dynamic>*) →* void};
+    #t200.{core::Set::add}{Invariant}(null){(dynamic) →* core::bool*};
+  } =>#t200;
+  core::Map<dynamic, dynamic>* map82 = block {
+    final core::Map<dynamic, dynamic>* #t201 = <dynamic, dynamic>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        for (final core::MapEntry<dynamic, dynamic>* #t202 in mapStringInt.{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, dynamic>>})
+          #t201.{core::Map::[]=}{Invariant}(#t202.{core::MapEntry::key}{dynamic}, #t202.{core::MapEntry::value}{dynamic}){(dynamic, dynamic) →* void};
+      else
+        for (final core::MapEntry<dynamic, dynamic>* #t203 in (dynVar as{TypeError,ForDynamic} core::Map<dynamic, dynamic>*).{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, dynamic>>})
+          #t201.{core::Map::[]=}{Invariant}(#t203.{core::MapEntry::key}{dynamic}, #t203.{core::MapEntry::value}{dynamic}){(dynamic, dynamic) →* void};
+    #t201.{core::Map::[]=}{Invariant}("baz", null){(dynamic, dynamic) →* void};
+  } =>#t201;
+  core::List<core::num*>* list83 = block {
+    final core::List<core::num*>* #t204 = <core::num*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t204.{core::List::add}{Invariant}(42){(core::num*) →* void};
+      else
+        #t204.{core::List::addAll}{Invariant}(listDouble){(core::Iterable<core::num*>*) →* void};
+  } =>#t204;
+  core::Set<core::num*>* set83 = block {
+    final core::Set<core::num*>* #t205 = col::LinkedHashSet::•<core::num*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t205.{core::Set::addAll}{Invariant}(listInt){(core::Iterable<core::num*>*) →* void};
+      else
+        #t205.{core::Set::add}{Invariant}(3.14){(core::num*) →* core::bool*};
+    #t205.{core::Set::add}{Invariant}(null){(core::num*) →* core::bool*};
+  } =>#t205;
+  core::Map<core::String*, core::num*>* map83 = block {
+    final core::Map<core::String*, core::num*>* #t206 = <core::String*, core::num*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        for (final core::MapEntry<core::String*, core::num*>* #t207 in mapStringInt.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::num*>>})
+          #t206.{core::Map::[]=}{Invariant}(#t207.{core::MapEntry::key}{core::String*}, #t207.{core::MapEntry::value}{core::num*}){(core::String*, core::num*) →* void};
+      else
+        #t206.{core::Map::[]=}{Invariant}("bar", 3.14){(core::String*, core::num*) →* void};
+    #t206.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::num*) →* void};
+  } =>#t206;
+  core::List<core::int*>* list90 = block {
+    final core::List<core::int*>* #t208 = <core::int*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t208.{core::List::add}{Invariant}(dynVar as{TypeError,ForDynamic} core::int*){(core::int*) →* void};
+  } =>#t208;
+  core::Set<core::int*>* set90 = block {
+    final core::Set<core::int*>* #t209 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t209.{core::Set::add}{Invariant}(dynVar as{TypeError,ForDynamic} core::int*){(core::int*) →* core::bool*};
+    #t209.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t209;
+  core::Map<core::String*, core::int*>* map90 = block {
+    final core::Map<core::String*, core::int*>* #t210 = <core::String*, core::int*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t210.{core::Map::[]=}{Invariant}("bar", dynVar as{TypeError,ForDynamic} core::int*){(core::String*, core::int*) →* void};
+    #t210.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t210;
+  core::List<core::int*>* list91 = block {
+    final core::List<core::int*>* #t211 = <core::int*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      for (final dynamic #t212 in dynVar as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+        final core::int* #t213 = #t212 as{TypeError} core::int*;
+        #t211.{core::List::add}{Invariant}(#t213){(core::int*) →* void};
+      }
+  } =>#t211;
+  core::Set<core::int*>* set91 = block {
+    final core::Set<core::int*>* #t214 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      for (final dynamic #t215 in dynVar as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+        final core::int* #t216 = #t215 as{TypeError} core::int*;
+        #t214.{core::Set::add}{Invariant}(#t216){(core::int*) →* core::bool*};
+      }
+    #t214.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t214;
+  core::Map<core::String*, core::int*>* map91 = block {
+    final core::Map<core::String*, core::int*>* #t217 = <core::String*, core::int*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      for (final core::MapEntry<dynamic, dynamic>* #t218 in (dynVar as{TypeError,ForDynamic} core::Map<dynamic, dynamic>*).{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>}) {
+        final core::String* #t219 = #t218.{core::MapEntry::key}{dynamic} as{TypeError} core::String*;
+        final core::int* #t220 = #t218.{core::MapEntry::value}{dynamic} as{TypeError} core::int*;
+        #t217.{core::Map::[]=}{Invariant}(#t219, #t220){(core::String*, core::int*) →* void};
+      }
+    #t217.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t217;
+  core::List<core::int*>* list100 = block {
+    final core::List<core::int*>* #t221 = <core::int*>[];
+    for (final core::int* #t222 = index = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; index = index.{core::num::+}(1){(core::num*) →* core::int*})
+      #t221.{core::List::add}{Invariant}(42){(core::int*) →* void};
+  } =>#t221;
+  core::Set<core::int*>* set100 = block {
+    final core::Set<core::int*>* #t223 = col::LinkedHashSet::•<core::int*>();
+    for (final core::int* #t224 = index = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; index = index.{core::num::+}(1){(core::num*) →* core::int*})
+      #t223.{core::Set::add}{Invariant}(42){(core::int*) →* core::bool*};
+  } =>#t223;
+  core::Map<core::String*, core::int*>* map100 = block {
+    final core::Map<core::String*, core::int*>* #t225 = <core::String*, core::int*>{};
+    for (final core::int* #t226 = index = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; index = index.{core::num::+}(1){(core::num*) →* core::int*})
+      #t225.{core::Map::[]=}{Invariant}("bar", 42){(core::String*, core::int*) →* void};
+  } =>#t225;
+  core::List<core::int*>* list110 = block {
+    final core::List<core::int*>* #t227 = <core::int*>[];
+    for (core::int* i in <core::int*>[1, 2, 3])
+      #t227.{core::List::add}{Invariant}(i){(core::int*) →* void};
+  } =>#t227;
+  core::Set<core::int*>* set110 = block {
+    final core::Set<core::int*>* #t228 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i in <core::int*>[1, 2, 3])
+      #t228.{core::Set::add}{Invariant}(i){(core::int*) →* core::bool*};
+    #t228.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t228;
+  core::Map<core::String*, core::int*>* map110 = block {
+    final core::Map<core::String*, core::int*>* #t229 = <core::String*, core::int*>{};
+    for (core::int* i in <core::int*>[1, 2, 3])
+      #t229.{core::Map::[]=}{Invariant}("bar", i){(core::String*, core::int*) →* void};
+    #t229.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t229;
+  core::List<core::int*>* list120 = block {
+    final core::List<core::int*>* #t230 = <core::int*>[];
+    for (dynamic i in dynVar as{TypeError,ForDynamic} core::Iterable<dynamic>*)
+      #t230.{core::List::add}{Invariant}(i as{TypeError,ForDynamic} core::int*){(core::int*) →* void};
+  } =>#t230;
+  core::Set<core::int*>* set120 = block {
+    final core::Set<core::int*>* #t231 = col::LinkedHashSet::•<core::int*>();
+    for (dynamic i in dynVar as{TypeError,ForDynamic} core::Iterable<dynamic>*)
+      #t231.{core::Set::add}{Invariant}(i as{TypeError,ForDynamic} core::int*){(core::int*) →* core::bool*};
+    #t231.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t231;
+  core::Map<core::String*, core::int*>* map120 = block {
+    final core::Map<core::String*, core::int*>* #t232 = <core::String*, core::int*>{};
+    for (dynamic i in dynVar as{TypeError,ForDynamic} core::Iterable<dynamic>*)
+      #t232.{core::Map::[]=}{Invariant}("bar", i as{TypeError,ForDynamic} core::int*){(core::String*, core::int*) →* void};
+    #t232.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t232;
+  core::List<core::int*>* list130 = block {
+    final core::List<core::int*>* #t233 = <core::int*>[];
+    for (core::int* i = 1; i.{core::num::<}(2){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t233.{core::List::add}{Invariant}(i){(core::int*) →* void};
+  } =>#t233;
+  core::Set<core::int*>* set130 = block {
+    final core::Set<core::int*>* #t234 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i = 1; i.{core::num::<}(2){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t234.{core::Set::add}{Invariant}(i){(core::int*) →* core::bool*};
+  } =>#t234;
+  core::Map<core::int*, core::int*>* map130 = block {
+    final core::Map<core::int*, core::int*>* #t235 = <core::int*, core::int*>{};
+    for (core::int* i = 1; i.{core::num::<}(2){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t235.{core::Map::[]=}{Invariant}(i, i){(core::int*, core::int*) →* void};
+  } =>#t235;
+}
+static method testForElementErrors(core::Map<core::int*, core::int*>* map, core::List<core::int*>* list) → dynamic async {
+  block {
+    final core::List<core::int*>* #t236 = <core::int*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t236.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:210:45: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <int>[for (int i = 0; oracle(\"foo\"); i++) \"bar\"];
+                                            ^" in "bar" as{TypeError} core::int*){(core::int*) →* void};
+  } =>#t236;
+  block {
+    final core::Set<core::int*>* #t237 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t237.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:211:45: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <int>{for (int i = 0; oracle(\"foo\"); i++) \"bar\", null};
+                                            ^" in "bar" as{TypeError} core::int*){(core::int*) →* core::bool*};
+    #t237.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t237;
+  block {
+    final core::Map<core::int*, core::int*>* #t238 = <core::int*, core::int*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t238.{core::Map::[]=}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:212:50: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <int, int>{for (int i = 0; oracle(\"foo\"); i++) \"bar\": \"bar\", \"baz\": null};
+                                                 ^" in "bar" as{TypeError} core::int*, invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:212:57: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <int, int>{for (int i = 0; oracle(\"foo\"); i++) \"bar\": \"bar\", \"baz\": null};
+                                                        ^" in "bar" as{TypeError} core::int*){(core::int*, core::int*) →* void};
+    #t238.{core::Map::[]=}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:212:64: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <int, int>{for (int i = 0; oracle(\"foo\"); i++) \"bar\": \"bar\", \"baz\": null};
+                                                               ^" in "baz" as{TypeError} core::int*, null){(core::int*, core::int*) →* void};
+  } =>#t238;
+  block {
+    final core::List<core::int*>* #t239 = <core::int*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t239.{core::List::addAll}{Invariant}(<core::int*>[invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:213:49: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <int>[for (int i = 0; oracle(\"foo\"); i++) ...[\"bar\"]];
+                                                ^" in "bar" as{TypeError} core::int*]){(core::Iterable<core::int*>*) →* void};
+  } =>#t239;
+  block {
+    final core::Set<core::int*>* #t240 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t240.{core::Set::addAll}{Invariant}(<core::int*>[invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:214:49: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <int>{for (int i = 0; oracle(\"foo\"); i++) ...[\"bar\"], null};
+                                                ^" in "bar" as{TypeError} core::int*]){(core::Iterable<core::int*>*) →* void};
+    #t240.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t240;
+  block {
+    final core::Map<core::int*, core::int*>* #t241 = <core::int*, core::int*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      for (final core::MapEntry<core::int*, core::int*>* #t242 in <core::int*, core::int*>{invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:215:54: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <int, int>{for (int i = 0; oracle(\"foo\"); i++) ...{\"bar\": \"bar\"}, \"baz\": null};
+                                                     ^" in "bar" as{TypeError} core::int*: invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:215:61: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <int, int>{for (int i = 0; oracle(\"foo\"); i++) ...{\"bar\": \"bar\"}, \"baz\": null};
+                                                            ^" in "bar" as{TypeError} core::int*}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int*, core::int*>>})
+        #t241.{core::Map::[]=}{Invariant}(#t242.{core::MapEntry::key}{core::int*}, #t242.{core::MapEntry::value}{core::int*}){(core::int*, core::int*) →* void};
+    #t241.{core::Map::[]=}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:215:69: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  <int, int>{for (int i = 0; oracle(\"foo\"); i++) ...{\"bar\": \"bar\"}, \"baz\": null};
+                                                                    ^" in "baz" as{TypeError} core::int*, null){(core::int*, core::int*) →* void};
+  } =>#t241;
+  block {
+    final core::List<core::int*>* #t243 = <core::int*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t243.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:216:48: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+ - 'Map' is from 'dart:core'.
+  <int>[for (int i = 0; oracle(\"foo\"); i++) ...map];
+                                               ^"){(core::int*) →* void};
+  } =>#t243;
+  block {
+    final core::Set<core::int*>* #t244 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t244.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:217:48: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+ - 'Map' is from 'dart:core'.
+  <int>{for (int i = 0; oracle(\"foo\"); i++) ...map, null};
+                                               ^"){(core::int*) →* core::bool*};
+    #t244.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t244;
+  <core::int*, core::int*>{invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:218:53: Error: Unexpected type 'List<int>' of a map spread entry.  Expected 'dynamic' or a Map.
+ - 'List' is from 'dart:core'.
+  <int, int>{for (int i = 0; oracle(\"foo\"); i++) ...list, 42: null};
+                                                    ^": null, invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:218:53: Error: Unexpected type 'List<int>' of a map spread entry.  Expected 'dynamic' or a Map.
+ - 'List' is from 'dart:core'.
+  <int, int>{for (int i = 0; oracle(\"foo\"); i++) ...list, 42: null};
+                                                    ^": null};
+  block {
+    final core::List<core::String*>* #t245 = <core::String*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t245.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:219:62: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  <String>[for (int i = 0; oracle(\"foo\"); i++) if (oracle()) 42 else 3.14];
+                                                             ^" in 42 as{TypeError} core::String*){(core::String*) →* void};
+      else
+        #t245.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:219:70: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+  <String>[for (int i = 0; oracle(\"foo\"); i++) if (oracle()) 42 else 3.14];
+                                                                     ^" in 3.14 as{TypeError} core::String*){(core::String*) →* void};
+  } =>#t245;
+  block {
+    final core::Set<core::String*>* #t246 = col::LinkedHashSet::•<core::String*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t246.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:220:62: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  <String>{for (int i = 0; oracle(\"foo\"); i++) if (oracle()) 42 else 3.14, null};
+                                                             ^" in 42 as{TypeError} core::String*){(core::String*) →* core::bool*};
+      else
+        #t246.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:220:70: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+  <String>{for (int i = 0; oracle(\"foo\"); i++) if (oracle()) 42 else 3.14, null};
+                                                                     ^" in 3.14 as{TypeError} core::String*){(core::String*) →* core::bool*};
+    #t246.{core::Set::add}{Invariant}(null){(core::String*) →* core::bool*};
+  } =>#t246;
+  block {
+    final core::Map<core::String*, core::String*>* #t247 = <core::String*, core::String*>{};
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t247.{core::Map::[]=}{Invariant}("bar", invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:221:77: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  <String, String>{for (int i = 0; oracle(\"foo\"); i++) if (oracle()) \"bar\": 42 else \"bar\": 3.14, \"baz\": null};
+                                                                            ^" in 42 as{TypeError} core::String*){(core::String*, core::String*) →* void};
+      else
+        #t247.{core::Map::[]=}{Invariant}("bar", invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:221:92: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+  <String, String>{for (int i = 0; oracle(\"foo\"); i++) if (oracle()) \"bar\": 42 else \"bar\": 3.14, \"baz\": null};
+                                                                                           ^" in 3.14 as{TypeError} core::String*){(core::String*, core::String*) →* void};
+    #t247.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::String*) →* void};
+  } =>#t247;
+  block {
+    final core::List<core::int*>* #t248 = <core::int*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t248.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:222:62: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+ - 'Map' is from 'dart:core'.
+  <int>[for (int i = 0; oracle(\"foo\"); i++) if (oracle()) ...map else 42];
+                                                             ^"){(core::int*) →* void};
+      else
+        #t248.{core::List::add}{Invariant}(42){(core::int*) →* void};
+  } =>#t248;
+  block {
+    final core::Set<core::int*>* #t249 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t249.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:223:62: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+ - 'Map' is from 'dart:core'.
+  <int>{for (int i = 0; oracle(\"foo\"); i++) if (oracle()) ...map else 42, null};
+                                                             ^"){(core::int*) →* core::bool*};
+      else
+        #t249.{core::Set::add}{Invariant}(42){(core::int*) →* core::bool*};
+    #t249.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t249;
+  <core::String*, core::int*>{invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:224:70: Error: Unexpected type 'List<int>' of a map spread entry.  Expected 'dynamic' or a Map.
+ - 'List' is from 'dart:core'.
+  <String, int>{for (int i = 0; oracle(\"foo\"); i++) if (oracle()) ...list else \"bar\": 42, \"baz\": null};
+                                                                     ^": null, invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:224:70: Error: Unexpected type 'List<int>' of a map spread entry.  Expected 'dynamic' or a Map.
+ - 'List' is from 'dart:core'.
+  <String, int>{for (int i = 0; oracle(\"foo\"); i++) if (oracle()) ...list else \"bar\": 42, \"baz\": null};
+                                                                     ^": null};
+  block {
+    final core::List<core::int*>* #t250 = <core::int*>[];
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t250.{core::List::add}{Invariant}(42){(core::int*) →* void};
+      else
+        #t250.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:225:70: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+ - 'Map' is from 'dart:core'.
+  <int>[for (int i = 0; oracle(\"foo\"); i++) if (oracle()) 42 else ...map];
+                                                                     ^"){(core::int*) →* void};
+  } =>#t250;
+  block {
+    final core::Set<core::int*>* #t251 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i = 0; self::oracle<core::String*>("foo") as{TypeError,ForDynamic} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      if(self::oracle<dynamic>() as{TypeError,ForDynamic} core::bool*)
+        #t251.{core::Set::add}{Invariant}(42){(core::int*) →* core::bool*};
+      else
+        #t251.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:226:70: Error: Unexpected type 'Map<int, int>' of a spread.  Expected 'dynamic' or an Iterable.
+ - 'Map' is from 'dart:core'.
+  <int>{for (int i = 0; oracle(\"foo\"); i++) if (oracle()) 42 else ...map, null};
+                                                                     ^"){(core::int*) →* core::bool*};
+    #t251.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t251;
+  <core::String*, core::int*>{invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:227:85: Error: Unexpected type 'List<int>' of a map spread entry.  Expected 'dynamic' or a Map.
+ - 'List' is from 'dart:core'.
+  <String, int>{for (int i = 0; oracle(\"foo\"); i++) if (oracle()) \"bar\": 42 else ...list, \"baz\": null};
+                                                                                    ^": null, invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:227:85: Error: Unexpected type 'List<int>' of a map spread entry.  Expected 'dynamic' or a Map.
+ - 'List' is from 'dart:core'.
+  <String, int>{for (int i = 0; oracle(\"foo\"); i++) if (oracle()) \"bar\": 42 else ...list, \"baz\": null};
+                                                                                    ^": null};
+  final core::int* i = 0;
+  block {
+    final core::List<core::int*>* #t252 = <core::int*>[];
+    for (final core::int* #t253 in <core::int*>[1]) {
+      invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:230:14: Error: Can't assign to the final variable 'i'.
+  <int>[for (i in <int>[1]) i];
+             ^";
+      #t252.{core::List::add}{Invariant}(i){(core::int*) →* void};
+    }
+  } =>#t252;
+  block {
+    final core::Set<core::int*>* #t254 = col::LinkedHashSet::•<core::int*>();
+    for (final core::int* #t255 in <core::int*>[1]) {
+      invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:231:14: Error: Can't assign to the final variable 'i'.
+  <int>{for (i in <int>[1]) i, null};
+             ^";
+      #t254.{core::Set::add}{Invariant}(i){(core::int*) →* core::bool*};
+    }
+    #t254.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t254;
+  block {
+    final core::Map<core::String*, core::int*>* #t256 = <core::String*, core::int*>{};
+    for (final core::int* #t257 in <core::int*>[1]) {
+      invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:232:21: Error: Can't assign to the final variable 'i'.
+\t<String, int>{for (i in <int>[1]) \"bar\": i, \"baz\": null};
+\t                   ^";
+      #t256.{core::Map::[]=}{Invariant}("bar", i){(core::String*, core::int*) →* void};
+    }
+    #t256.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t256;
+  core::List<dynamic>* list10 = block {
+    final core::List<dynamic>* #t258 = <dynamic>[];
+    for (dynamic i in invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:234:31: Error: The type 'String' used in the 'for' loop must implement 'Iterable<dynamic>'.
+ - 'Iterable' is from 'dart:core'.
+  var list10 = [for (var i in \"not iterable\") i];
+                              ^" in "not iterable" as{TypeError} core::Iterable<dynamic>*)
+      #t258.{core::List::add}{Invariant}(i){(dynamic) →* void};
+  } =>#t258;
+  core::Set<dynamic>* set10 = block {
+    final core::Set<dynamic>* #t259 = col::LinkedHashSet::•<dynamic>();
+    for (dynamic i in invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:235:30: Error: The type 'String' used in the 'for' loop must implement 'Iterable<dynamic>'.
+ - 'Iterable' is from 'dart:core'.
+  var set10 = {for (var i in \"not iterable\") i, null};
+                             ^" in "not iterable" as{TypeError} core::Iterable<dynamic>*)
+      #t259.{core::Set::add}{Invariant}(i){(dynamic) →* core::bool*};
+    #t259.{core::Set::add}{Invariant}(null){(dynamic) →* core::bool*};
+  } =>#t259;
+  core::Map<core::String*, dynamic>* map10 = block {
+    final core::Map<core::String*, dynamic>* #t260 = <core::String*, dynamic>{};
+    for (dynamic i in invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:236:30: Error: The type 'String' used in the 'for' loop must implement 'Iterable<dynamic>'.
+ - 'Iterable' is from 'dart:core'.
+  var map10 = {for (var i in \"not iterable\") \"bar\": i, \"baz\": null};
+                             ^" in "not iterable" as{TypeError} core::Iterable<dynamic>*)
+      #t260.{core::Map::[]=}{Invariant}("bar", i){(core::String*, dynamic) →* void};
+    #t260.{core::Map::[]=}{Invariant}("baz", null){(core::String*, dynamic) →* void};
+  } =>#t260;
+  core::List<core::int*>* list20 = block {
+    final core::List<core::int*>* #t261 = <core::int*>[];
+    for (core::int* i in <core::int*>[invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:237:32: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  var list20 = [for (int i in [\"not\", \"int\"]) i];
+                               ^" in "not" as{TypeError} core::int*, invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:237:39: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  var list20 = [for (int i in [\"not\", \"int\"]) i];
+                                      ^" in "int" as{TypeError} core::int*])
+      #t261.{core::List::add}{Invariant}(i){(core::int*) →* void};
+  } =>#t261;
+  core::Set<core::int*>* set20 = block {
+    final core::Set<core::int*>* #t262 = col::LinkedHashSet::•<core::int*>();
+    for (core::int* i in <core::int*>[invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:238:31: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  var set20 = {for (int i in [\"not\", \"int\"]) i, null};
+                              ^" in "not" as{TypeError} core::int*, invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:238:38: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  var set20 = {for (int i in [\"not\", \"int\"]) i, null};
+                                     ^" in "int" as{TypeError} core::int*])
+      #t262.{core::Set::add}{Invariant}(i){(core::int*) →* core::bool*};
+    #t262.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t262;
+  core::Map<core::String*, core::int*>* map20 = block {
+    final core::Map<core::String*, core::int*>* #t263 = <core::String*, core::int*>{};
+    for (core::int* i in <core::int*>[invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:239:31: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  var map20 = {for (int i in [\"not\", \"int\"]) \"bar\": i, \"baz\": null};
+                              ^" in "not" as{TypeError} core::int*, invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:239:38: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  var map20 = {for (int i in [\"not\", \"int\"]) \"bar\": i, \"baz\": null};
+                                     ^" in "int" as{TypeError} core::int*])
+      #t263.{core::Map::[]=}{Invariant}("bar", i){(core::String*, core::int*) →* void};
+    #t263.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t263;
+  core::List<dynamic>* list30 = block {
+    final core::List<dynamic>* #t264 = <dynamic>[];
+    await for (dynamic i in invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:240:37: Error: The type 'String' used in the 'for' loop must implement 'Stream<dynamic>'.
+ - 'Stream' is from 'dart:async'.
+  var list30 = [await for (var i in \"not stream\") i];
+                                    ^" in "not stream" as{TypeError} asy::Stream<dynamic>*)
+      #t264.{core::List::add}{Invariant}(i){(dynamic) →* void};
+  } =>#t264;
+  core::Set<dynamic>* set30 = block {
+    final core::Set<dynamic>* #t265 = col::LinkedHashSet::•<dynamic>();
+    await for (dynamic i in invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:241:36: Error: The type 'String' used in the 'for' loop must implement 'Stream<dynamic>'.
+ - 'Stream' is from 'dart:async'.
+  var set30 = {await for (var i in \"not stream\") i, null};
+                                   ^" in "not stream" as{TypeError} asy::Stream<dynamic>*)
+      #t265.{core::Set::add}{Invariant}(i){(dynamic) →* core::bool*};
+    #t265.{core::Set::add}{Invariant}(null){(dynamic) →* core::bool*};
+  } =>#t265;
+  core::Map<core::String*, dynamic>* map30 = block {
+    final core::Map<core::String*, dynamic>* #t266 = <core::String*, dynamic>{};
+    await for (dynamic i in invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:242:36: Error: The type 'String' used in the 'for' loop must implement 'Stream<dynamic>'.
+ - 'Stream' is from 'dart:async'.
+  var map30 = {await for (var i in \"not stream\") \"bar\": i, \"baz\": null};
+                                   ^" in "not stream" as{TypeError} asy::Stream<dynamic>*)
+      #t266.{core::Map::[]=}{Invariant}("bar", i){(core::String*, dynamic) →* void};
+    #t266.{core::Map::[]=}{Invariant}("baz", null){(core::String*, dynamic) →* void};
+  } =>#t266;
+  core::List<core::int*>* list40 = block {
+    final core::List<core::int*>* #t267 = <core::int*>[];
+    await for (core::int* i in asy::Stream::fromIterable<core::int*>(<core::int*>[invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:243:58: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  var list40 = [await for (int i in Stream.fromIterable([\"not\", \"int\"])) i];
+                                                         ^" in "not" as{TypeError} core::int*, invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:243:65: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  var list40 = [await for (int i in Stream.fromIterable([\"not\", \"int\"])) i];
+                                                                ^" in "int" as{TypeError} core::int*]))
+      #t267.{core::List::add}{Invariant}(i){(core::int*) →* void};
+  } =>#t267;
+  core::Set<core::int*>* set40 = block {
+    final core::Set<core::int*>* #t268 = col::LinkedHashSet::•<core::int*>();
+    await for (core::int* i in asy::Stream::fromIterable<core::int*>(<core::int*>[invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:244:57: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  var set40 = {await for (int i in Stream.fromIterable([\"not\", \"int\"])) i, null};
+                                                        ^" in "not" as{TypeError} core::int*, invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:244:64: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  var set40 = {await for (int i in Stream.fromIterable([\"not\", \"int\"])) i, null};
+                                                               ^" in "int" as{TypeError} core::int*]))
+      #t268.{core::Set::add}{Invariant}(i){(core::int*) →* core::bool*};
+    #t268.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t268;
+  core::Map<core::String*, core::int*>* map40 = block {
+    final core::Map<core::String*, core::int*>* #t269 = <core::String*, core::int*>{};
+    await for (core::int* i in asy::Stream::fromIterable<core::int*>(<core::int*>[invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:245:57: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  var map40 = {await for (int i in Stream.fromIterable([\"not\", \"int\"])) \"bar\": i, \"baz\": null};
+                                                        ^" in "not" as{TypeError} core::int*, invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:245:64: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  var map40 = {await for (int i in Stream.fromIterable([\"not\", \"int\"])) \"bar\": i, \"baz\": null};
+                                                               ^" in "int" as{TypeError} core::int*]))
+      #t269.{core::Map::[]=}{Invariant}("bar", i){(core::String*, core::int*) →* void};
+    #t269.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t269;
+  core::List<core::int*>* list50 = block {
+    final core::List<core::int*>* #t270 = <core::int*>[];
+    for (; ; )
+      #t270.{core::List::add}{Invariant}(42){(core::int*) →* void};
+  } =>#t270;
+  core::Set<core::int*>* set50 = block {
+    final core::Set<core::int*>* #t271 = col::LinkedHashSet::•<core::int*>();
+    for (; ; )
+      #t271.{core::Set::add}{Invariant}(42){(core::int*) →* core::bool*};
+    #t271.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t271;
+  core::Map<core::String*, core::int*>* map50 = block {
+    final core::Map<core::String*, core::int*>* #t272 = <core::String*, core::int*>{};
+    for (; ; )
+      #t272.{core::Map::[]=}{Invariant}("bar", 42){(core::String*, core::int*) →* void};
+    #t272.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t272;
+  core::List<core::int*>* list60 = block {
+    final core::List<core::int*>* #t273 = <core::int*>[];
+    for (; invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:249:24: Error: A value of type 'String' can't be assigned to a variable of type 'bool'.
+  var list60 = [for (; \"not bool\";) 42];
+                       ^" in "not bool" as{TypeError} core::bool*; )
+      #t273.{core::List::add}{Invariant}(42){(core::int*) →* void};
+  } =>#t273;
+  core::Set<core::int*>* set60 = block {
+    final core::Set<core::int*>* #t274 = col::LinkedHashSet::•<core::int*>();
+    for (; invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:250:23: Error: A value of type 'String' can't be assigned to a variable of type 'bool'.
+  var set60 = {for (; \"not bool\";) 42, null};
+                      ^" in "not bool" as{TypeError} core::bool*; )
+      #t274.{core::Set::add}{Invariant}(42){(core::int*) →* core::bool*};
+    #t274.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t274;
+  core::Map<core::String*, core::int*>* map60 = block {
+    final core::Map<core::String*, core::int*>* #t275 = <core::String*, core::int*>{};
+    for (; invalid-expression "pkg/front_end/testcases/general/control_flow_collection_inference.dart:251:23: Error: A value of type 'String' can't be assigned to a variable of type 'bool'.
+  var map60 = {for (; \"not bool\";) \"bar\": 42, \"baz\": null};
+                      ^" in "not bool" as{TypeError} core::bool*; )
+      #t275.{core::Map::[]=}{Invariant}("bar", 42){(core::String*, core::int*) →* void};
+    #t275.{core::Map::[]=}{Invariant}("baz", null){(core::String*, core::int*) →* void};
+  } =>#t275;
+}
+static method testForElementErrorsNotAsync(asy::Stream<core::int*>* stream) → dynamic {
+  block {
+    final core::List<core::int*>* #t276 = <core::int*>[];
+    await for (core::int* i in stream)
+      #t276.{core::List::add}{Invariant}(i){(core::int*) →* void};
+  } =>#t276;
+  block {
+    final core::Set<core::int*>* #t277 = col::LinkedHashSet::•<core::int*>();
+    await for (core::int* i in stream)
+      #t277.{core::Set::add}{Invariant}(i){(core::int*) →* core::bool*};
+  } =>#t277;
+  block {
+    final core::Map<core::String*, core::int*>* #t278 = <core::String*, core::int*>{};
+    await for (core::int* i in stream)
+      #t278.{core::Map::[]=}{Invariant}("bar", i){(core::String*, core::int*) →* void};
+  } =>#t278;
+}
+static method testPromotion(self::A* a) → dynamic {
+  core::List<core::int*>* list10 = block {
+    final core::List<core::int*>* #t279 = <core::int*>[];
+    if(a is self::B*)
+      #t279.{core::List::add}{Invariant}(a{self::B*}.{self::B::foo}{core::int*}){(core::int*) →* void};
+  } =>#t279;
+  core::Set<core::int*>* set10 = block {
+    final core::Set<core::int*>* #t280 = col::LinkedHashSet::•<core::int*>();
+    if(a is self::B*)
+      #t280.{core::Set::add}{Invariant}(a{self::B*}.{self::B::foo}{core::int*}){(core::int*) →* core::bool*};
+  } =>#t280;
+  core::Map<core::int*, core::int*>* map10 = block {
+    final core::Map<core::int*, core::int*>* #t281 = <core::int*, core::int*>{};
+    if(a is self::B*)
+      #t281.{core::Map::[]=}{Invariant}(a{self::B*}.{self::B::foo}{core::int*}, a{self::B*}.{self::B::foo}{core::int*}){(core::int*, core::int*) →* void};
+  } =>#t281;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/covariant_equals.dart.weak.modular.expect b/pkg/front_end/testcases/general/covariant_equals.dart.weak.modular.expect
new file mode 100644
index 0000000..3f1296f
--- /dev/null
+++ b/pkg/front_end/testcases/general/covariant_equals.dart.weak.modular.expect
@@ -0,0 +1,284 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:24:8: Error: The argument type 'C<dynamic>' can't be assigned to the parameter type 'A'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   a == c_dynamic; // error
+//        ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:25:8: Error: The argument type 'C<int>' can't be assigned to the parameter type 'A'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   a == c_int; // error
+//        ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:26:8: Error: The argument type 'C<String>' can't be assigned to the parameter type 'A'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   a == c_string; // error
+//        ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:27:8: Error: The argument type 'D' can't be assigned to the parameter type 'A'.
+//  - 'D' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   a == d; // error
+//        ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:31:8: Error: The argument type 'C<dynamic>' can't be assigned to the parameter type 'A'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   b == c_dynamic; // error
+//        ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:32:8: Error: The argument type 'C<int>' can't be assigned to the parameter type 'A'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   b == c_int; // error
+//        ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:33:8: Error: The argument type 'C<String>' can't be assigned to the parameter type 'A'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   b == c_string; // error
+//        ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:34:8: Error: The argument type 'D' can't be assigned to the parameter type 'A'.
+//  - 'D' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   b == d; // error
+//        ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:36:16: Error: The argument type 'A' can't be assigned to the parameter type 'C<dynamic>'.
+//  - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   c_dynamic == a; // error
+//                ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:37:16: Error: The argument type 'B' can't be assigned to the parameter type 'C<dynamic>'.
+//  - 'B' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   c_dynamic == b; // error
+//                ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:43:12: Error: The argument type 'A' can't be assigned to the parameter type 'C<int>'.
+//  - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   c_int == a; // error
+//            ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:44:12: Error: The argument type 'B' can't be assigned to the parameter type 'C<int>'.
+//  - 'B' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   c_int == b; // error
+//            ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:47:12: Error: The argument type 'C<String>' can't be assigned to the parameter type 'C<int>'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   c_int == c_string; // error
+//            ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:50:15: Error: The argument type 'A' can't be assigned to the parameter type 'C<String>'.
+//  - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   c_string == a; // error
+//               ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:51:15: Error: The argument type 'B' can't be assigned to the parameter type 'C<String>'.
+//  - 'B' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   c_string == b; // error
+//               ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:53:15: Error: The argument type 'C<int>' can't be assigned to the parameter type 'C<String>'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   c_string == c_int; // error
+//               ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:55:15: Error: The argument type 'D' can't be assigned to the parameter type 'C<String>'.
+//  - 'D' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   c_string == d; // error
+//               ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:57:8: Error: The argument type 'A' can't be assigned to the parameter type 'C<int>'.
+//  - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   d == a; // error
+//        ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:58:8: Error: The argument type 'B' can't be assigned to the parameter type 'C<int>'.
+//  - 'B' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   d == b; // error
+//        ^
+//
+// pkg/front_end/testcases/general/covariant_equals.dart:61:8: Error: The argument type 'C<String>' can't be assigned to the parameter type 'C<int>'.
+//  - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+//   d == c_string; // error
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator ==(covariant-by-declaration self::A* other) → core::bool*
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator ==(covariant-by-declaration self::A* other) → core::bool*
+    return true;
+}
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  operator ==(covariant-by-declaration covariant-by-class self::C<self::C::T*>* other) → core::bool*
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C<core::int*> {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+}
+static method main() → dynamic {}
+static method test(self::A* a, self::B* b, self::C<dynamic>* c_dynamic, self::C<core::int*>* c_int, self::C<core::String*>* c_string, self::D* d) → dynamic {
+  a =={self::A::==}{(self::A*) →* core::bool*} a;
+  a =={self::A::==}{(self::A*) →* core::bool*} b;
+  a =={self::A::==}{(self::A*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:24:8: Error: The argument type 'C<dynamic>' can't be assigned to the parameter type 'A'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  a == c_dynamic; // error
+       ^" in c_dynamic as{TypeError} self::A*;
+  a =={self::A::==}{(self::A*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:25:8: Error: The argument type 'C<int>' can't be assigned to the parameter type 'A'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  a == c_int; // error
+       ^" in c_int as{TypeError} self::A*;
+  a =={self::A::==}{(self::A*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:26:8: Error: The argument type 'C<String>' can't be assigned to the parameter type 'A'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  a == c_string; // error
+       ^" in c_string as{TypeError} self::A*;
+  a =={self::A::==}{(self::A*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:27:8: Error: The argument type 'D' can't be assigned to the parameter type 'A'.
+ - 'D' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  a == d; // error
+       ^" in d as{TypeError} self::A*;
+  b =={self::B::==}{(self::A*) →* core::bool*} a;
+  b =={self::B::==}{(self::A*) →* core::bool*} b;
+  b =={self::B::==}{(self::A*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:31:8: Error: The argument type 'C<dynamic>' can't be assigned to the parameter type 'A'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  b == c_dynamic; // error
+       ^" in c_dynamic as{TypeError} self::A*;
+  b =={self::B::==}{(self::A*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:32:8: Error: The argument type 'C<int>' can't be assigned to the parameter type 'A'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  b == c_int; // error
+       ^" in c_int as{TypeError} self::A*;
+  b =={self::B::==}{(self::A*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:33:8: Error: The argument type 'C<String>' can't be assigned to the parameter type 'A'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  b == c_string; // error
+       ^" in c_string as{TypeError} self::A*;
+  b =={self::B::==}{(self::A*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:34:8: Error: The argument type 'D' can't be assigned to the parameter type 'A'.
+ - 'D' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  b == d; // error
+       ^" in d as{TypeError} self::A*;
+  c_dynamic =={self::C::==}{(self::C<dynamic>*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:36:16: Error: The argument type 'A' can't be assigned to the parameter type 'C<dynamic>'.
+ - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  c_dynamic == a; // error
+               ^" in a as{TypeError} self::C<dynamic>*;
+  c_dynamic =={self::C::==}{(self::C<dynamic>*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:37:16: Error: The argument type 'B' can't be assigned to the parameter type 'C<dynamic>'.
+ - 'B' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  c_dynamic == b; // error
+               ^" in b as{TypeError} self::C<dynamic>*;
+  c_dynamic =={self::C::==}{(self::C<dynamic>*) →* core::bool*} c_dynamic;
+  c_dynamic =={self::C::==}{(self::C<dynamic>*) →* core::bool*} c_int;
+  c_dynamic =={self::C::==}{(self::C<dynamic>*) →* core::bool*} c_string;
+  c_dynamic =={self::C::==}{(self::C<dynamic>*) →* core::bool*} d;
+  c_int =={self::C::==}{(self::C<core::int*>*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:43:12: Error: The argument type 'A' can't be assigned to the parameter type 'C<int>'.
+ - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  c_int == a; // error
+           ^" in a as{TypeError} self::C<core::int*>*;
+  c_int =={self::C::==}{(self::C<core::int*>*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:44:12: Error: The argument type 'B' can't be assigned to the parameter type 'C<int>'.
+ - 'B' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  c_int == b; // error
+           ^" in b as{TypeError} self::C<core::int*>*;
+  c_int =={self::C::==}{(self::C<core::int*>*) →* core::bool*} c_dynamic as{TypeError} self::C<core::int*>*;
+  c_int =={self::C::==}{(self::C<core::int*>*) →* core::bool*} c_int;
+  c_int =={self::C::==}{(self::C<core::int*>*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:47:12: Error: The argument type 'C<String>' can't be assigned to the parameter type 'C<int>'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  c_int == c_string; // error
+           ^" in c_string as{TypeError} self::C<core::int*>*;
+  c_int =={self::C::==}{(self::C<core::int*>*) →* core::bool*} d;
+  c_string =={self::C::==}{(self::C<core::String*>*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:50:15: Error: The argument type 'A' can't be assigned to the parameter type 'C<String>'.
+ - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  c_string == a; // error
+              ^" in a as{TypeError} self::C<core::String*>*;
+  c_string =={self::C::==}{(self::C<core::String*>*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:51:15: Error: The argument type 'B' can't be assigned to the parameter type 'C<String>'.
+ - 'B' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  c_string == b; // error
+              ^" in b as{TypeError} self::C<core::String*>*;
+  c_string =={self::C::==}{(self::C<core::String*>*) →* core::bool*} c_dynamic as{TypeError} self::C<core::String*>*;
+  c_string =={self::C::==}{(self::C<core::String*>*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:53:15: Error: The argument type 'C<int>' can't be assigned to the parameter type 'C<String>'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  c_string == c_int; // error
+              ^" in c_int as{TypeError} self::C<core::String*>*;
+  c_string =={self::C::==}{(self::C<core::String*>*) →* core::bool*} c_string;
+  c_string =={self::C::==}{(self::C<core::String*>*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:55:15: Error: The argument type 'D' can't be assigned to the parameter type 'C<String>'.
+ - 'D' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  c_string == d; // error
+              ^" in d as{TypeError} self::C<core::String*>*;
+  d =={self::C::==}{(self::C<core::int*>*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:57:8: Error: The argument type 'A' can't be assigned to the parameter type 'C<int>'.
+ - 'A' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  d == a; // error
+       ^" in a as{TypeError} self::C<core::int*>*;
+  d =={self::C::==}{(self::C<core::int*>*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:58:8: Error: The argument type 'B' can't be assigned to the parameter type 'C<int>'.
+ - 'B' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  d == b; // error
+       ^" in b as{TypeError} self::C<core::int*>*;
+  d =={self::C::==}{(self::C<core::int*>*) →* core::bool*} c_dynamic as{TypeError} self::C<core::int*>*;
+  d =={self::C::==}{(self::C<core::int*>*) →* core::bool*} c_int;
+  d =={self::C::==}{(self::C<core::int*>*) →* core::bool*} invalid-expression "pkg/front_end/testcases/general/covariant_equals.dart:61:8: Error: The argument type 'C<String>' can't be assigned to the parameter type 'C<int>'.
+ - 'C' is from 'pkg/front_end/testcases/general/covariant_equals.dart'.
+  d == c_string; // error
+       ^" in c_string as{TypeError} self::C<core::int*>*;
+  d =={self::C::==}{(self::C<core::int*>*) →* core::bool*} d;
+}
diff --git a/pkg/front_end/testcases/general/covariant_field.dart.weak.modular.expect b/pkg/front_end/testcases/general/covariant_field.dart.weak.modular.expect
new file mode 100644
index 0000000..6453946
--- /dev/null
+++ b/pkg/front_end/testcases/general/covariant_field.dart.weak.modular.expect
@@ -0,0 +1,90 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/covariant_field.dart:19:31: Error: The parameter 'value' of the method 'C.invariantField' has type 'int', which does not match the corresponding type, 'num', in the overridden method, 'A.invariantField'.
+// Change to a supertype of 'num', or, for a covariant parameter, a subtype.
+//   void set invariantField(int value) {} // error
+//                               ^
+// pkg/front_end/testcases/general/covariant_field.dart:6:7: Context: This is the overridden method ('invariantField').
+//   num invariantField;
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::num* invariantField = null;
+  covariant-by-declaration field core::num* covariantField = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object implements self::A {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract get invariantField() → core::num*;
+  abstract set invariantField(core::num* value) → void;
+  abstract get covariantField() → core::num*;
+  abstract set covariantField(covariant-by-declaration core::num* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object implements self::A {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract get invariantField() → core::int*;
+  set invariantField(core::int* value) → void {}
+  abstract get covariantField() → core::int*;
+  set covariantField(covariant-by-declaration core::int* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D extends core::Object implements self::A {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract get invariantField() → core::int*;
+  set invariantField(covariant-by-declaration core::int* value) → void {}
+  abstract get covariantField() → core::int*;
+  set covariantField(covariant-by-declaration core::int* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/covariant_field_override.dart.weak.modular.expect b/pkg/front_end/testcases/general/covariant_field_override.dart.weak.modular.expect
new file mode 100644
index 0000000..fb69f60
--- /dev/null
+++ b/pkg/front_end/testcases/general/covariant_field_override.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::num* field = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  covariant-by-declaration field core::num* field = null;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::A implements self::B {
+  covariant-by-declaration field core::num* field = null;
+  synthetic constructor •() → self::C*
+    : super self::A::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/covariant_generic.dart.weak.modular.expect b/pkg/front_end/testcases/general/covariant_generic.dart.weak.modular.expect
new file mode 100644
index 0000000..f28d890
--- /dev/null
+++ b/pkg/front_end/testcases/general/covariant_generic.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef Callback<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+class Foo<T extends core::Object* = dynamic> extends core::Object {
+  final field self::Foo::T* finalField;
+  final field (self::Foo::T*) →* void callbackField;
+  covariant-by-class field self::Foo::T* mutableField = null;
+  field (self::Foo::T*) →* void mutableCallbackField = null;
+  constructor •(self::Foo::T* finalField, (self::Foo::T*) →* void callbackField) → self::Foo<self::Foo::T*>*
+    : self::Foo::finalField = finalField, self::Foo::callbackField = callbackField, super core::Object::•()
+    ;
+  method method(covariant-by-class self::Foo::T* x) → void {}
+  set setter(covariant-by-class self::Foo::T* x) → void {}
+  method withCallback((self::Foo::T*) →* void callback) → void {
+    callback(this.{self::Foo::finalField}{self::Foo::T*}){(self::Foo::T*) →* void};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::Foo<core::int*>* fooInt = new self::Foo::•<core::int*>(1, (core::int* x) → Null {});
+  fooInt.{self::Foo::method}(3){(core::int*) →* void};
+  fooInt.{self::Foo::setter} = 3;
+  fooInt.{self::Foo::withCallback}((core::int* x) → Null {}){((core::int*) →* void) →* void};
+  fooInt.{self::Foo::withCallback}((core::num* x) → Null {}){((core::int*) →* void) →* void};
+  fooInt.{self::Foo::mutableField} = 3;
+  fooInt.{self::Foo::mutableCallbackField} = (core::int* x) → Null {};
+  self::Foo<core::num*>* fooNum = fooInt;
+  fooNum.{self::Foo::method}(3){(core::num*) →* void};
+  fooNum.{self::Foo::method}(2.5){(core::num*) →* void};
+  fooNum.{self::Foo::setter} = 3;
+  fooNum.{self::Foo::setter} = 2.5;
+  fooNum.{self::Foo::withCallback}((core::num* x) → Null {}){((core::num*) →* void) →* void};
+  fooNum.{self::Foo::mutableField} = 3;
+  fooNum.{self::Foo::mutableField} = 2.5;
+  let final self::Foo<core::num*>* #t1 = fooNum in let final core::int* #t2 = 3 in (#t1.{self::Foo::mutableCallbackField}{(core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void)(#t2){(core::num*) →* void};
+  let final self::Foo<core::num*>* #t3 = fooNum in let final core::double* #t4 = 2.5 in (#t3.{self::Foo::mutableCallbackField}{(core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void)(#t4){(core::num*) →* void};
+  fooNum.{self::Foo::mutableCallbackField} = (core::num* x) → Null {};
+}
diff --git a/pkg/front_end/testcases/general/covariant_parameter_in_superclass_of_mixin_application.dart.weak.modular.expect b/pkg/front_end/testcases/general/covariant_parameter_in_superclass_of_mixin_application.dart.weak.modular.expect
new file mode 100644
index 0000000..0390bb6
--- /dev/null
+++ b/pkg/front_end/testcases/general/covariant_parameter_in_superclass_of_mixin_application.dart.weak.modular.expect
@@ -0,0 +1,66 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method foo(covariant-by-declaration core::num* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method foo(core::num* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method foo(core::num* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _D&A&B = self::A with self::B /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_D&A&B*
+    : super self::A::•()
+    ;
+  forwarding-stub method foo(covariant-by-declaration core::num* x) → void
+    return super.{self::B::foo}(x);
+}
+class D extends self::_D&A&B implements self::C {
+  synthetic constructor •() → self::D*
+    : super self::_D&A&B::•()
+    ;
+  method foo(covariant-by-declaration core::int* x) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/covariant_super_check.dart.weak.modular.expect b/pkg/front_end/testcases/general/covariant_super_check.dart.weak.modular.expect
new file mode 100644
index 0000000..044d867
--- /dev/null
+++ b/pkg/front_end/testcases/general/covariant_super_check.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/covariant_super_check.dart:16:27: Error: The parameter 'a' of the method 'C.method' has type 'String', which does not match the corresponding type, 'num', in the overridden method, 'A.method'.
+// Change to a supertype of 'num', or, for a covariant parameter, a subtype.
+//   method(covariant String a) {}
+//                           ^
+// pkg/front_end/testcases/general/covariant_super_check.dart:6:3: Context: This is the overridden method ('method').
+//   method(num a) {}
+//   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method method(core::num* a) → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  method method(dynamic a) → dynamic {}
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  method method(covariant-by-declaration core::String* a) → dynamic {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/covariant_type_parameter.dart.weak.modular.expect b/pkg/front_end/testcases/general/covariant_type_parameter.dart.weak.modular.expect
new file mode 100644
index 0000000..d28fb6f
--- /dev/null
+++ b/pkg/front_end/testcases/general/covariant_type_parameter.dart.weak.modular.expect
@@ -0,0 +1,51 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<S extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::S*>*
+    : super core::Object::•()
+    ;
+  method method<covariant-by-class T extends self::A::S*>(covariant-by-class self::A::S* s) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<S extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::S*>*
+    : super core::Object::•()
+    ;
+  method method<covariant-by-class T extends self::B::S*>(covariant-by-declaration covariant-by-class self::B::S* s) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<S extends core::Object* = dynamic> extends self::A<self::C::S*> implements self::B<self::C::S*> {
+  synthetic constructor •() → self::C<self::C::S*>*
+    : super self::A::•()
+    ;
+  forwarding-stub forwarding-semi-stub method method<covariant-by-class T extends self::C::S*>(covariant-by-declaration covariant-by-class self::C::S* s) → void
+    return super.{self::A::method}<self::C::method::T*>(s);
+}
+class D<S extends core::Object* = dynamic> extends self::A<self::D::S*> implements self::B<self::D::S*> {
+  synthetic constructor •() → self::D<self::D::S*>*
+    : super self::A::•()
+    ;
+  forwarding-stub method method<covariant-by-class T extends self::D::S*>(covariant-by-declaration covariant-by-class self::D::S* s) → void
+    return super.{self::A::method}<self::D::method::T*>(s);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/crashes/crash_01/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/crashes/crash_01/main.dart.weak.modular.expect
new file mode 100644
index 0000000..fb38c29
--- /dev/null
+++ b/pkg/front_end/testcases/general/crashes/crash_01/main.dart.weak.modular.expect
@@ -0,0 +1,51 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "main_lib.dart" as mai;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+class SliverConstraints extends core::Object {
+  synthetic constructor •() → self::SliverConstraints
+    : super core::Object::•()
+    ;
+}
+abstract class RenderSliver extends mai::RenderObject {
+  synthetic constructor •() → self::RenderSliver
+    : super mai::RenderObject::•()
+    ;
+  get constraints() → self::SliverConstraints
+    return super.{mai::RenderObject::constraints} as{ForNonNullableByDefault} self::SliverConstraints;
+}
+abstract class _RenderSliverSingleBoxAdapter&RenderSliver&RenderObjectWithChildMixin = self::RenderSliver with mai::RenderObjectWithChildMixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_RenderSliverSingleBoxAdapter&RenderSliver&RenderObjectWithChildMixin
+    : super self::RenderSliver::•()
+    ;
+  abstract member-signature get constraints() → invalid-type; -> self::RenderSliver::constraints
+}
+abstract class RenderSliverSingleBoxAdapter extends self::_RenderSliverSingleBoxAdapter&RenderSliver&RenderObjectWithChildMixin {
+  synthetic constructor •() → self::RenderSliverSingleBoxAdapter
+    : super self::_RenderSliverSingleBoxAdapter&RenderSliver&RenderObjectWithChildMixin::•()
+    ;
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/crashes/crash_01/main_lib.dart:2:3: Error: Type 'Constraints' not found.
+//   Constraints get constraints {}
+//   ^^^^^^^^^^^
+//
+import self as mai;
+import "dart:core" as core;
+
+abstract class RenderObject extends core::Object {
+  synthetic constructor •() → mai::RenderObject
+    : super core::Object::•()
+    ;
+  get constraints() → invalid-type {}
+}
+abstract class RenderObjectWithChildMixin extends mai::RenderObject /*isMixinDeclaration*/  {
+}
diff --git a/pkg/front_end/testcases/general/crashes/crash_03/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/crashes/crash_03/main.dart.weak.modular.expect
new file mode 100644
index 0000000..923fadf
--- /dev/null
+++ b/pkg/front_end/testcases/general/crashes/crash_03/main.dart.weak.modular.expect
@@ -0,0 +1,79 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/crashes/crash_03/main.dart:7:57: Error: Type 'MouseTrackerAnnotation' not found.
+// mixin _PlatformViewGestureMixin on RenderBox implements MouseTrackerAnnotation {
+//                                                         ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/crashes/crash_03/main.dart:9:7: Error: The getter '_hitTestBehavior' isn't defined for the class '_PlatformViewGestureMixin'.
+//  - '_PlatformViewGestureMixin' is from 'pkg/front_end/testcases/general/crashes/crash_03/main.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named '_hitTestBehavior'.
+//       _hitTestBehavior != PlatformViewHitTestBehavior.transparent;
+//       ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/crashes/crash_03/main.dart:9:27: Error: The getter 'PlatformViewHitTestBehavior' isn't defined for the class '_PlatformViewGestureMixin'.
+//  - '_PlatformViewGestureMixin' is from 'pkg/front_end/testcases/general/crashes/crash_03/main.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'PlatformViewHitTestBehavior'.
+//       _hitTestBehavior != PlatformViewHitTestBehavior.transparent;
+//                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "main_lib.dart" as mai;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+class Offset extends core::Object {
+  synthetic constructor •() → self::Offset
+    : super core::Object::•()
+    ;
+}
+abstract class _PlatformViewRenderBox&RenderBox&_PlatformViewGestureMixin = mai::RenderBox with self::_PlatformViewGestureMixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_PlatformViewRenderBox&RenderBox&_PlatformViewGestureMixin
+    : super mai::RenderBox::•()
+    ;
+  mixin-super-stub method hitTestSelf(self::Offset position) → core::bool
+    return super.{self::_PlatformViewGestureMixin::hitTestSelf}(position);
+}
+class PlatformViewRenderBox extends self::_PlatformViewRenderBox&RenderBox&_PlatformViewGestureMixin {
+  synthetic constructor •() → self::PlatformViewRenderBox
+    : super self::_PlatformViewRenderBox&RenderBox&_PlatformViewGestureMixin::•()
+    ;
+}
+abstract class _PlatformViewGestureMixin extends mai::RenderBox /*isMixinDeclaration*/  {
+  method hitTestSelf(self::Offset position) → core::bool
+    return !(invalid-expression "pkg/front_end/testcases/general/crashes/crash_03/main.dart:9:7: Error: The getter '_hitTestBehavior' isn't defined for the class '_PlatformViewGestureMixin'.
+ - '_PlatformViewGestureMixin' is from 'pkg/front_end/testcases/general/crashes/crash_03/main.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named '_hitTestBehavior'.
+      _hitTestBehavior != PlatformViewHitTestBehavior.transparent;
+      ^^^^^^^^^^^^^^^^" in this{<unresolved>}._hitTestBehavior =={core::Object::==}{(core::Object) → core::bool} invalid-expression "pkg/front_end/testcases/general/crashes/crash_03/main.dart:9:27: Error: The getter 'PlatformViewHitTestBehavior' isn't defined for the class '_PlatformViewGestureMixin'.
+ - '_PlatformViewGestureMixin' is from 'pkg/front_end/testcases/general/crashes/crash_03/main.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'PlatformViewHitTestBehavior'.
+      _hitTestBehavior != PlatformViewHitTestBehavior.transparent;
+                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^" in this{<unresolved>}.PlatformViewHitTestBehavior{dynamic}.transparent);
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/crashes/crash_03/main_lib.dart:2:20: Error: Type 'Offset' not found.
+//   bool hitTestSelf(Offset position) => false;
+//                    ^^^^^^
+//
+// pkg/front_end/testcases/general/crashes/crash_03/main_lib.dart:2:20: Error: 'Offset' isn't a type.
+//   bool hitTestSelf(Offset position) => false;
+//                    ^^^^^^
+//
+import self as mai;
+import "dart:core" as core;
+
+abstract class RenderBox extends core::Object {
+  synthetic constructor •() → mai::RenderBox
+    : super core::Object::•()
+    ;
+  method hitTestSelf(invalid-type position) → core::bool
+    return false;
+}
diff --git a/pkg/front_end/testcases/general/crashes/crash_04/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/crashes/crash_04/main.dart.weak.modular.expect
new file mode 100644
index 0000000..9b02f5d
--- /dev/null
+++ b/pkg/front_end/testcases/general/crashes/crash_04/main.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/crashes/crash_04/main.dart:1:19: Error: Type 'C' not found.
+// mixin A<T extends C> on D {}
+//                   ^
+//
+// pkg/front_end/testcases/general/crashes/crash_04/main.dart:1:25: Error: Type 'D' not found.
+// mixin A<T extends C> on D {}
+//                         ^
+//
+// pkg/front_end/testcases/general/crashes/crash_04/main.dart:3:17: Error: Type 'D' not found.
+// class B extends D with A {}
+//                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A<T extends invalid-type> extends core::Object /*isMixinDeclaration*/  {
+}
+abstract class _B&D&A = core::Object with self::A<invalid-type> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B&D&A
+    : super core::Object::•()
+    ;
+}
+class B extends self::_B&D&A {
+  synthetic constructor •() → self::B
+    : super self::_B&D&A::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/crashes/crash_05/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/crashes/crash_05/main.dart.weak.modular.expect
new file mode 100644
index 0000000..3a5d2de
--- /dev/null
+++ b/pkg/front_end/testcases/general/crashes/crash_05/main.dart.weak.modular.expect
@@ -0,0 +1,98 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/crashes/crash_05/main.dart:6:20: Error: Type 'PointerEvent' not found.
+//   void handleEvent(PointerEvent event, SliverHitTestEntry entry) {}
+//                    ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/crashes/crash_05/main.dart:10:37: Error: Type 'RenderBox' not found.
+//     with RenderObjectWithChildMixin<RenderBox>, RenderSliverHelpers {}
+//                                     ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/crashes/crash_05/main.dart:10:49: Error: Type 'RenderSliverHelpers' not found.
+//     with RenderObjectWithChildMixin<RenderBox>, RenderSliverHelpers {}
+//                                                 ^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/crashes/crash_05/main.dart:9:16: Error: The type 'RenderSliverHelpers' can't be mixed in.
+// abstract class RenderSliverSingleBoxAdapter extends RenderSliver
+//                ^
+//
+// pkg/front_end/testcases/general/crashes/crash_05/main.dart:9:16: Error: 'RenderSliver' doesn't implement 'RenderObject' so it can't be used with 'RenderObjectWithChildMixin<invalid-type>'.
+//  - 'RenderSliver' is from 'pkg/front_end/testcases/general/crashes/crash_05/main.dart'.
+//  - 'RenderObject' is from 'pkg/front_end/testcases/general/crashes/crash_05/main_lib.dart'.
+//  - 'RenderObjectWithChildMixin' is from 'pkg/front_end/testcases/general/crashes/crash_05/main_lib.dart'.
+// abstract class RenderSliverSingleBoxAdapter extends RenderSliver
+//                ^
+//
+// pkg/front_end/testcases/general/crashes/crash_05/main.dart:6:20: Error: 'PointerEvent' isn't a type.
+//   void handleEvent(PointerEvent event, SliverHitTestEntry entry) {}
+//                    ^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "main_lib.dart" as mai;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+class SliverHitTestEntry extends core::Object {
+  synthetic constructor •() → self::SliverHitTestEntry
+    : super core::Object::•()
+    ;
+}
+abstract class RenderSliver extends core::Object {
+  synthetic constructor •() → self::RenderSliver
+    : super core::Object::•()
+    ;
+  method handleEvent(invalid-type event, self::SliverHitTestEntry entry) → void {}
+}
+abstract class _RenderSliverSingleBoxAdapter&RenderSliver&RenderObjectWithChildMixin = self::RenderSliver with mai::RenderObjectWithChildMixin<invalid-type> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_RenderSliverSingleBoxAdapter&RenderSliver&RenderObjectWithChildMixin
+    : super self::RenderSliver::•()
+    ;
+  forwarding-stub method handleEvent(invalid-type event, covariant-by-declaration invalid-type entry) → void
+    return super.{self::RenderSliver::handleEvent}(event, entry);
+}
+abstract class _RenderSliverSingleBoxAdapter&RenderSliver&RenderObjectWithChildMixin&RenderSliverHelpers extends self::_RenderSliverSingleBoxAdapter&RenderSliver&RenderObjectWithChildMixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_RenderSliverSingleBoxAdapter&RenderSliver&RenderObjectWithChildMixin&RenderSliverHelpers
+    : super self::_RenderSliverSingleBoxAdapter&RenderSliver&RenderObjectWithChildMixin::•()
+    ;
+}
+abstract class RenderSliverSingleBoxAdapter extends self::_RenderSliverSingleBoxAdapter&RenderSliver&RenderObjectWithChildMixin&RenderSliverHelpers {
+  synthetic constructor •() → self::RenderSliverSingleBoxAdapter
+    : super self::_RenderSliverSingleBoxAdapter&RenderSliver&RenderObjectWithChildMixin&RenderSliverHelpers::•()
+    ;
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/crashes/crash_05/main_lib.dart:2:20: Error: Type 'PointerEvent' not found.
+//   void handleEvent(PointerEvent event, covariant HitTestEntry entry) {}
+//                    ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/crashes/crash_05/main_lib.dart:2:50: Error: Type 'HitTestEntry' not found.
+//   void handleEvent(PointerEvent event, covariant HitTestEntry entry) {}
+//                                                  ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/crashes/crash_05/main_lib.dart:2:20: Error: 'PointerEvent' isn't a type.
+//   void handleEvent(PointerEvent event, covariant HitTestEntry entry) {}
+//                    ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/crashes/crash_05/main_lib.dart:2:50: Error: 'HitTestEntry' isn't a type.
+//   void handleEvent(PointerEvent event, covariant HitTestEntry entry) {}
+//                                                  ^^^^^^^^^^^^
+//
+import self as mai;
+import "dart:core" as core;
+
+abstract class RenderObject extends core::Object {
+  synthetic constructor •() → mai::RenderObject
+    : super core::Object::•()
+    ;
+  method handleEvent(invalid-type event, covariant-by-declaration invalid-type entry) → void {}
+}
+abstract class RenderObjectWithChildMixin<ChildType extends mai::RenderObject> extends mai::RenderObject /*isMixinDeclaration*/  {
+}
diff --git a/pkg/front_end/testcases/general/cycles.dart.weak.modular.expect b/pkg/front_end/testcases/general/cycles.dart.weak.modular.expect
new file mode 100644
index 0000000..ec6f025
--- /dev/null
+++ b/pkg/front_end/testcases/general/cycles.dart.weak.modular.expect
@@ -0,0 +1,85 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/cycles.dart:5:7: Error: 'A' is a supertype of itself.
+// class A implements C {}
+//       ^
+//
+// pkg/front_end/testcases/general/cycles.dart:7:7: Error: 'B' is a supertype of itself.
+// class B extends A {}
+//       ^
+//
+// pkg/front_end/testcases/general/cycles.dart:9:7: Error: 'C' is a supertype of itself.
+// class C extends B implements D {}
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::print(new self::A::•());
+  core::print(new self::B::•());
+  core::print(new self::C::•());
+  core::print(new self::D::•());
+}
diff --git a/pkg/front_end/testcases/general/default_values.dart.weak.modular.expect b/pkg/front_end/testcases/general/default_values.dart.weak.modular.expect
new file mode 100644
index 0000000..7b8886e
--- /dev/null
+++ b/pkg/front_end/testcases/general/default_values.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method topLevel([dynamic a = #C1]) → dynamic
+  return a;
+static method main() → dynamic {
+  core::print(self::topLevel());
+}
+
+constants  {
+  #C1 = 42
+}
diff --git a/pkg/front_end/testcases/general/deferred_type_annotation.dart.weak.modular.expect b/pkg/front_end/testcases/general/deferred_type_annotation.dart.weak.modular.expect
new file mode 100644
index 0000000..bdaedd7
--- /dev/null
+++ b/pkg/front_end/testcases/general/deferred_type_annotation.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/deferred_type_annotation.dart:7:5: Error: The type 'C' is deferred loaded via prefix 'd' and can't be used as a type annotation.
+//  - 'C' is from 'pkg/front_end/testcases/general/deferred_lib.dart'.
+// Try removing 'deferred' from the import of 'd' or use a supertype of 'C' that isn't deferred.
+// bad(d.C x) {}
+//     ^^^
+//
+import self as self;
+import "deferred_lib.dart" as def;
+
+import "org-dartlang-testcase:///deferred_lib.dart" deferred as d;
+
+static method bad(def::C* x) → dynamic {}
+static method main() → dynamic {}
+
+library;
+import self as def;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::int* y = 1;
+  synthetic constructor •() → def::C*
+    : super core::Object::•()
+    ;
+  static method m() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* x = 0;
+static method m(dynamic x) → dynamic
+  return null;
diff --git a/pkg/front_end/testcases/general/demote_closure_types.dart.weak.modular.expect b/pkg/front_end/testcases/general/demote_closure_types.dart.weak.modular.expect
new file mode 100644
index 0000000..f789104
--- /dev/null
+++ b/pkg/front_end/testcases/general/demote_closure_types.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/demote_closure_types.dart:8:17: Error: A value of type 'T' can't be assigned to a variable of type 'String'.
+//     String s = f();
+//                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method method<T extends core::Object* = dynamic>(self::method::T* a, self::method::T* b) → dynamic {
+  if(a is core::String*) {
+    () →* self::method::T* f = () → self::method::T* => a{self::method::T* & core::String* /* '*' & '*' = '*' */};
+    core::String* s = invalid-expression "pkg/front_end/testcases/general/demote_closure_types.dart:8:17: Error: A value of type 'T' can't be assigned to a variable of type 'String'.
+    String s = f();
+                ^" in f(){() →* self::method::T*} as{TypeError} core::String*;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/duplicate_instantiation.dart.weak.modular.expect b/pkg/front_end/testcases/general/duplicate_instantiation.dart.weak.modular.expect
new file mode 100644
index 0000000..05dcdaa
--- /dev/null
+++ b/pkg/front_end/testcases/general/duplicate_instantiation.dart.weak.modular.expect
@@ -0,0 +1,346 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:13:8: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   Class<int>;
+//        ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:15:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>;
+//            ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:15:18: Error: Expected '[' before this.
+//   Class<int><int>;
+//                  ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:16:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>();
+//            ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:16:20: Error: Unexpected token ';'.
+//   Class<int><int>();
+//                    ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:16:20: Error: Expected a function body or '=>'.
+// Try adding {}.
+//   Class<int><int>();
+//                    ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:16:20: Error: Expected ';' after this.
+//   Class<int><int>();
+//                    ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:17:8: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   Class<int>.named;
+//        ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:17:14: Error: Member not found: 'named'.
+//   Class<int>.named;
+//              ^^^^^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:19:8: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   Class<int>.named<int>;
+//        ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:19:19: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   Class<int>.named<int>;
+//                   ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:19:14: Error: Member not found: 'named'.
+//   Class<int>.named<int>;
+//              ^^^^^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:20:8: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   Class<int>.named<int>();
+//        ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:20:14: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   Class<int>.named<int>();
+//              ^^^^^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:21:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named;
+//            ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:21:18: Error: Expected '[' before this.
+//   Class<int><int>.named;
+//                  ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:22:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named();
+//            ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:22:18: Error: Expected '[' before this.
+//   Class<int><int>.named();
+//                  ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:23:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int>;
+//            ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:23:18: Error: Expected '[' before this.
+//   Class<int><int>.named<int>;
+//                  ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:23:24: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   Class<int><int>.named<int>;
+//                        ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:24:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int>();
+//            ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:24:18: Error: Expected '[' before this.
+//   Class<int><int>.named<int>();
+//                  ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:25:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int><int>;
+//            ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:25:18: Error: Expected '[' before this.
+//   Class<int><int>.named<int><int>;
+//                  ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:25:24: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int><int>;
+//                        ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:25:28: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int><int>;
+//                            ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:25:34: Error: Expected '[' before this.
+//   Class<int><int>.named<int><int>;
+//                                  ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:26:12: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int><int>();
+//            ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:26:18: Error: Expected '[' before this.
+//   Class<int><int>.named<int><int>();
+//                  ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:26:24: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int><int>();
+//                        ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:26:28: Error: A comparison expression can't be an operand of another comparison expression.
+// Try putting parentheses around one of the comparisons.
+//   Class<int><int>.named<int><int>();
+//                            ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:26:36: Error: Unexpected token ';'.
+//   Class<int><int>.named<int><int>();
+//                                    ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:26:36: Error: Expected a function body or '=>'.
+// Try adding {}.
+//   Class<int><int>.named<int><int>();
+//                                    ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:26:36: Error: Expected ';' after this.
+//   Class<int><int>.named<int><int>();
+//                                    ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:15:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>;
+//        ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:16:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>();
+//        ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:21:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>.named;
+//        ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:21:19: Error: The getter 'named' isn't defined for the class 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'named'.
+//   Class<int><int>.named;
+//                   ^^^^^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:22:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>.named();
+//        ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:22:19: Error: The method 'named' isn't defined for the class 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Try correcting the name to the name of an existing method, or defining a method named 'named'.
+//   Class<int><int>.named();
+//                   ^^^^^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:23:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>.named<int>;
+//        ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:23:19: Error: The getter 'named' isn't defined for the class 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'named'.
+//   Class<int><int>.named<int>;
+//                   ^^^^^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:24:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>.named<int>();
+//        ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:24:19: Error: The method 'named' isn't defined for the class 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Try correcting the name to the name of an existing method, or defining a method named 'named'.
+//   Class<int><int>.named<int>();
+//                   ^^^^^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:25:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>.named<int><int>;
+//        ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:25:19: Error: The getter 'named' isn't defined for the class 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'named'.
+//   Class<int><int>.named<int><int>;
+//                   ^^^^^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:26:8: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   Class<int><int>.named<int><int>();
+//        ^
+//
+// pkg/front_end/testcases/general/duplicate_instantiation.dart:26:19: Error: The getter 'named' isn't defined for the class 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'named'.
+//   Class<int><int>.named<int><int>();
+//                   ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  constructor named() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+}
+static method test() → dynamic {
+  #C1;
+  new self::Class::•<core::int>();
+  invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:15:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>;
+       ^" in #C1{<unresolved>}.<(#C2){dynamic}.>(<core::int>[]);
+  invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:16:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>();
+       ^" in #C1{<unresolved>}.<(#C2){dynamic}.>(<int extends core::Object? = dynamic>() → Null
+    ;
+);
+  invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:17:14: Error: Member not found: 'named'.
+  Class<int>.named;
+             ^^^^^";
+  new self::Class::named<core::int>();
+  invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:19:14: Error: Member not found: 'named'.
+  Class<int>.named<int>;
+             ^^^^^";
+  new self::Class::named<core::int>();
+  invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:21:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>.named;
+       ^" in #C1{<unresolved>}.<(#C2){dynamic}.>(invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:21:19: Error: The getter 'named' isn't defined for the class 'List<int>'.
+ - 'List' is from 'dart:core'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'named'.
+  Class<int><int>.named;
+                  ^^^^^" in <core::int>[]{<unresolved>}.named);
+  invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:22:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>.named();
+       ^" in #C1{<unresolved>}.<(#C2){dynamic}.>(invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:22:19: Error: The method 'named' isn't defined for the class 'List<int>'.
+ - 'List' is from 'dart:core'.
+Try correcting the name to the name of an existing method, or defining a method named 'named'.
+  Class<int><int>.named();
+                  ^^^^^" in <core::int>[]{<unresolved>}.named());
+  invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:23:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>.named<int>;
+       ^" in #C1{<unresolved>}.<(#C2){dynamic}.>(invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:23:19: Error: The getter 'named' isn't defined for the class 'List<int>'.
+ - 'List' is from 'dart:core'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'named'.
+  Class<int><int>.named<int>;
+                  ^^^^^" in <core::int>[]{<unresolved>}.named);
+  invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:24:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>.named<int>();
+       ^" in #C1{<unresolved>}.<(#C2){dynamic}.>(invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:24:19: Error: The method 'named' isn't defined for the class 'List<int>'.
+ - 'List' is from 'dart:core'.
+Try correcting the name to the name of an existing method, or defining a method named 'named'.
+  Class<int><int>.named<int>();
+                  ^^^^^" in <core::int>[]{<unresolved>}.named<core::int>());
+  invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:25:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>.named<int><int>;
+       ^" in #C1{<unresolved>}.<(#C2){dynamic}.>(invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:25:19: Error: The getter 'named' isn't defined for the class 'List<int>'.
+ - 'List' is from 'dart:core'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'named'.
+  Class<int><int>.named<int><int>;
+                  ^^^^^" in <core::int>[]{<unresolved>}.named){dynamic}.<(#C2){dynamic}.>(<core::int>[]);
+  invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:26:8: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  Class<int><int>.named<int><int>();
+       ^" in #C1{<unresolved>}.<(#C2){dynamic}.>(invalid-expression "pkg/front_end/testcases/general/duplicate_instantiation.dart:26:19: Error: The getter 'named' isn't defined for the class 'List<int>'.
+ - 'List' is from 'dart:core'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'named'.
+  Class<int><int>.named<int><int>();
+                  ^^^^^" in <core::int>[]{<unresolved>}.named){dynamic}.<(#C2){dynamic}.>(<int extends core::Object? = dynamic>() → Null
+    ;
+);
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = TypeLiteralConstant(self::Class<dynamic>*)
+  #C2 = TypeLiteralConstant(core::int*)
+}
diff --git a/pkg/front_end/testcases/general/duplicate_typedef.dart.weak.modular.expect b/pkg/front_end/testcases/general/duplicate_typedef.dart.weak.modular.expect
new file mode 100644
index 0000000..6428f44
--- /dev/null
+++ b/pkg/front_end/testcases/general/duplicate_typedef.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/duplicate_typedef.dart:6:9: Error: 'F' is already declared in this scope.
+// typedef F = void Function();
+//         ^
+// pkg/front_end/testcases/general/duplicate_typedef.dart:5:9: Context: Previous declaration of 'F'.
+// typedef F = void Function();
+//         ^
+//
+// pkg/front_end/testcases/general/duplicate_typedef.dart:9:9: Error: 'G' is already declared in this scope.
+// typedef G<T> = void Function(T);
+//         ^
+// pkg/front_end/testcases/general/duplicate_typedef.dart:8:9: Context: Previous declaration of 'G'.
+// typedef G<T> = void Function(T);
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F = () → void;
+typedef G<contravariant T extends core::Object? = dynamic> = (T%) → void;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/duplicated_bad_prefix.dart.weak.modular.expect b/pkg/front_end/testcases/general/duplicated_bad_prefix.dart.weak.modular.expect
new file mode 100644
index 0000000..c5b39f8
--- /dev/null
+++ b/pkg/front_end/testcases/general/duplicated_bad_prefix.dart.weak.modular.expect
@@ -0,0 +1,117 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/duplicated_bad_prefix.dart:12:7: Error: 'Dupe' is already declared in this scope.
+// class Dupe {}
+//       ^^^^
+// pkg/front_end/testcases/general/duplicated_bad_prefix.dart:10:7: Context: Previous declaration of 'Dupe'.
+// class Dupe {}
+//       ^^^^
+//
+// pkg/front_end/testcases/general/duplicated_bad_prefix.dart:15:3: Error: Type 'Dupe.a' not found.
+//   Dupe.a b;
+//   ^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_bad_prefix.dart:8:45: Error: 'C' is imported from both 'pkg/front_end/testcases/general/duplicated_bad_prefix_lib1.dart' and 'pkg/front_end/testcases/general/duplicated_bad_prefix_lib2.dart'.
+// import 'duplicated_bad_prefix_lib2.dart' as dupe;
+//                                             ^
+//
+// pkg/front_end/testcases/general/duplicated_bad_prefix.dart:15:3: Error: 'Dupe.a' isn't a type.
+//   Dupe.a b;
+//   ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///duplicated_bad_prefix_lib1.dart" as dupe;
+import "org-dartlang-testcase:///duplicated_bad_prefix_lib2.dart" as dupe;
+
+class Dupe#1 extends core::Object {
+  synthetic constructor •() → self::Dupe#1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Dupe extends core::Object {
+  synthetic constructor •() → self::Dupe*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  field invalid-type b = null;
+  field invalid-type d = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self2::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+library;
+import self as self3;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self3::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/general/duplicated_declarations.dart.weak.modular.expect b/pkg/front_end/testcases/general/duplicated_declarations.dart.weak.modular.expect
new file mode 100644
index 0000000..183d7ef
--- /dev/null
+++ b/pkg/front_end/testcases/general/duplicated_declarations.dart.weak.modular.expect
@@ -0,0 +1,693 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:7:1: Error: Import directives must precede part directives.
+// Try moving the import directives before the part directives.
+// import 'duplicated_declarations_lib.dart' as Typedef;
+// ^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:9:1: Error: Import directives must precede part directives.
+// Try moving the import directives before the part directives.
+// import 'duplicated_declarations_lib.dart' as Typedef;
+// ^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:13:9: Error: 'Typedef' is already declared in this scope.
+// typedef Typedef = Object Function();
+//         ^^^^^^^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:11:9: Context: Previous declaration of 'Typedef'.
+// typedef Typedef = void Function();
+//         ^^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:15:1: Error: Directives must appear before any declarations.
+// Try moving the directive before any declarations.
+// import 'duplicated_declarations_lib.dart' as Typedef;
+// ^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:19:16: Error: 'OldTypedef' is already declared in this scope.
+// typedef Object OldTypedef();
+//                ^^^^^^^^^^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:17:14: Context: Previous declaration of 'OldTypedef'.
+// typedef void OldTypedef();
+//              ^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:23:5: Error: 'field' is already declared in this scope.
+// var field = "2nd";
+//     ^^^^^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:21:5: Context: Previous declaration of 'field'.
+// var field = "1st";
+//     ^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:29:1: Error: 'main' is already declared in this scope.
+// main() {
+// ^^^^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:25:1: Context: Previous declaration of 'main'.
+// main() {
+// ^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:43:3: Error: 'C' is already declared in this scope.
+//   C(a, b);
+//   ^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:42:3: Context: Previous declaration of 'C'.
+//   C(a);
+//   ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:46:7: Error: 'field' is already declared in this scope.
+//   var field = "2nd";
+//       ^^^^^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:44:7: Context: Previous declaration of 'field'.
+//   var field = "1st";
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:52:3: Error: 'm' is already declared in this scope.
+//   m() {
+//   ^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:48:3: Context: Previous declaration of 'm'.
+//   m() {
+//   ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:60:10: Error: 's' is already declared in this scope.
+//   static s() {
+//          ^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:56:10: Context: Previous declaration of 's'.
+//   static s() {
+//          ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:72:7: Error: 'C' is already declared in this scope.
+// class C {
+//       ^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:41:7: Context: Previous declaration of 'C'.
+// class C {
+//       ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:77:3: Error: Name of enum constant 'Enum' can't be the same as the enum's own name.
+//   Enum,
+//   ^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:79:3: Error: 'a' is already declared in this scope.
+//   a,
+//   ^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:78:3: Context: Previous declaration of 'a'.
+//   a,
+//   ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:83:6: Error: 'Enum' is already declared in this scope.
+// enum Enum {
+//      ^^^^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:76:6: Context: Previous declaration of 'Enum'.
+// enum Enum {
+//      ^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:95:3: Error: 'toString' is already declared in this scope.
+//   toString,
+//   ^^^^^^^^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:89:6: Context: Previous declaration of 'toString' is implied by this definition.
+// enum AnotherEnum {
+//      ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:96:3: Error: 'values' is already declared in this scope.
+//   values,
+//   ^^^^^^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:89:6: Context: Previous declaration of 'values' is implied by this definition.
+// enum AnotherEnum {
+//      ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:11:9: Error: 'Typedef' is already declared in this scope.
+// typedef Typedef = void Function();
+//         ^^^^^^^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:13:9: Context: Previous declaration of 'Typedef'.
+// typedef Typedef = Object Function();
+//         ^^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:17:14: Error: 'OldTypedef' is already declared in this scope.
+// typedef void OldTypedef();
+//              ^^^^^^^^^^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:19:16: Context: Previous declaration of 'OldTypedef'.
+// typedef Object OldTypedef();
+//                ^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:21:5: Error: 'field' is already declared in this scope.
+// var field = "3rd";
+//     ^^^^^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:23:5: Context: Previous declaration of 'field'.
+// var field = "2nd";
+//     ^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:27:1: Error: 'main' is already declared in this scope.
+// main() {
+// ^^^^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:29:1: Context: Previous declaration of 'main'.
+// main() {
+// ^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:39:7: Error: 'C' is already declared in this scope.
+// class C {
+//       ^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:72:7: Context: Previous declaration of 'C'.
+// class C {
+//       ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:73:6: Error: 'Enum' is already declared in this scope.
+// enum Enum {
+//      ^^^^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:83:6: Context: Previous declaration of 'Enum'.
+// enum Enum {
+//      ^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:7:1: Error: The part-of directive must be the only directive in a part.
+// Try removing the other directives, or moving them to the library for which this is a part.
+// import 'duplicated_declarations_lib.dart' as Typedef;
+// ^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:9:1: Error: The part-of directive must be the only directive in a part.
+// Try removing the other directives, or moving them to the library for which this is a part.
+// import 'duplicated_declarations_lib.dart' as Typedef;
+// ^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:13:9: Error: 'Typedef' is already declared in this scope.
+// typedef Typedef = Object Function();
+//         ^^^^^^^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:11:9: Context: Previous declaration of 'Typedef'.
+// typedef Typedef = void Function();
+//         ^^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:15:1: Error: The part-of directive must be the only directive in a part.
+// Try removing the other directives, or moving them to the library for which this is a part.
+// import 'duplicated_declarations_lib.dart' as Typedef;
+// ^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:19:16: Error: 'OldTypedef' is already declared in this scope.
+// typedef Object OldTypedef();
+//                ^^^^^^^^^^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:17:14: Context: Previous declaration of 'OldTypedef'.
+// typedef void OldTypedef();
+//              ^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:23:5: Error: 'field' is already declared in this scope.
+// var field = 4;
+//     ^^^^^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:21:5: Context: Previous declaration of 'field'.
+// var field = "3rd";
+//     ^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:25:5: Error: 'field' is already declared in this scope.
+// var field = 5.0;
+//     ^^^^^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:23:5: Context: Previous declaration of 'field'.
+// var field = 4;
+//     ^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:31:1: Error: 'main' is already declared in this scope.
+// main() {
+// ^^^^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:27:1: Context: Previous declaration of 'main'.
+// main() {
+// ^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:35:1: Error: 'main' is already declared in this scope.
+// main() {
+// ^^^^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:31:1: Context: Previous declaration of 'main'.
+// main() {
+// ^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:41:3: Error: 'C' is already declared in this scope.
+//   C(a, b);
+//   ^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:40:3: Context: Previous declaration of 'C'.
+//   C(a);
+//   ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:44:7: Error: 'field' is already declared in this scope.
+//   var field = "2nd";
+//       ^^^^^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:42:7: Context: Previous declaration of 'field'.
+//   var field = "1st";
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:50:3: Error: 'm' is already declared in this scope.
+//   m() {
+//   ^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:46:3: Context: Previous declaration of 'm'.
+//   m() {
+//   ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:58:10: Error: 's' is already declared in this scope.
+//   static s() {
+//          ^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:54:10: Context: Previous declaration of 's'.
+//   static s() {
+//          ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:65:7: Error: 'C' is already declared in this scope.
+// class C {
+//       ^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:39:7: Context: Previous declaration of 'C'.
+// class C {
+//       ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:69:7: Error: 'C' is already declared in this scope.
+// class C {
+//       ^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:65:7: Context: Previous declaration of 'C'.
+// class C {
+//       ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:74:3: Error: Name of enum constant 'Enum' can't be the same as the enum's own name.
+//   Enum,
+//   ^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:76:3: Error: 'a' is already declared in this scope.
+//   a,
+//   ^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:75:3: Context: Previous declaration of 'a'.
+//   a,
+//   ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:80:6: Error: 'Enum' is already declared in this scope.
+// enum Enum {
+//      ^^^^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:73:6: Context: Previous declaration of 'Enum'.
+// enum Enum {
+//      ^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:86:6: Error: 'Enum' is already declared in this scope.
+// enum Enum {
+//      ^^^^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:80:6: Context: Previous declaration of 'Enum'.
+// enum Enum {
+//      ^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:7:46: Error: 'Typedef' is already declared in this scope.
+// import 'duplicated_declarations_lib.dart' as Typedef;
+//                                              ^^^^^^^
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:13:9: Context: Previous declaration of 'Typedef'.
+// typedef Typedef = Object Function();
+//         ^^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:67:19: Error: 'C' isn't a type.
+// class Sub extends C {
+//                   ^
+// pkg/front_end/testcases/general/duplicated_declarations.dart:67:19: Context: This isn't a type.
+// class Sub extends C {
+//                   ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:94:3: Error: Can't declare a member that conflicts with an inherited one.
+//   index,
+//   ^^^^^
+// sdk/lib/core/enum.dart:74:13: Context: This is the inherited member.
+//   final int index;
+//             ^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:34:3: Error: Can't use 'main' because it is declared more than once.
+//   main();
+//   ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:35:9: Error: Can't use 'field' because it is declared more than once.
+//   print(field);
+//         ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:36:3: Error: Can't use 'C' because it is declared more than once.
+//   C.s();
+//   ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:37:5: Error: Expected identifier, but got 'this'.
+//   C.this();
+//     ^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:38:6: Error: Expected an identifier, but got ')'.
+// Try inserting an identifier before ')'.
+//   C.();
+//      ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:38:5: Error: Expected an identifier, but got '('.
+// Try inserting an identifier before '('.
+//   C.();
+//     ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:64:17: Error: Can't use 's' because it is declared more than once.
+//   static f() => s;
+//                 ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:68:16: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//   Sub() : super(null);
+//                ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:69:16: Error: Superclass has no method named 'm'.
+//   m() => super.m();
+//                ^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:106:41: Error: Can't use 'toString' because it is declared more than once.
+//     "AnotherEnum.toString": AnotherEnum.toString,
+//                                         ^^^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations.dart:107:39: Error: Can't use 'values' because it is declared more than once.
+//     "AnotherEnum.values": AnotherEnum.values,
+//                                       ^^^^^^
+//
+// pkg/front_end/testcases/general/duplicated_declarations_part.dart:62:17: Error: Can't use 's' because it is declared more than once.
+//   static f() => s;
+//                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///duplicated_declarations_lib.dart" as Typedef;
+import "org-dartlang-testcase:///duplicated_declarations_lib.dart" as Typedef;
+import "org-dartlang-testcase:///duplicated_declarations_lib.dart" as Typedef;
+import "org-dartlang-testcase:///duplicated_declarations_lib.dart" as Typedef;
+import "org-dartlang-testcase:///duplicated_declarations_lib.dart" as Typedef;
+import "org-dartlang-testcase:///duplicated_declarations_lib.dart" as Typedef;
+
+part duplicated_declarations_part.dart;
+typedef Typedef = () →* void;
+typedef OldTypedef = () →* void;
+class C#4 extends core::Object { // from org-dartlang-testcase:///duplicated_declarations_part.dart
+  constructor _() → self::C#4*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C#3 extends core::Object { // from org-dartlang-testcase:///duplicated_declarations_part.dart
+  constructor _() → self::C#3*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C#2 extends core::Object { // from org-dartlang-testcase:///duplicated_declarations_part.dart
+  field core::String* field = null;
+  constructor •(dynamic a) → self::C#2*
+    : super core::Object::•()
+    ;
+  method m() → dynamic {
+    "1st";
+  }
+  static method s() → dynamic {
+    "1st";
+  }
+  static method f() → dynamic
+    return invalid-expression "pkg/front_end/testcases/general/duplicated_declarations_part.dart:62:17: Error: Can't use 's' because it is declared more than once.
+  static f() => s;
+                ^";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C#1 extends core::Object {
+  constructor _() → self::C#1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  field core::String* field = null;
+  constructor •(dynamic a) → self::C*
+    : super core::Object::•()
+    ;
+  method m() → dynamic {
+    "1st";
+  }
+  static method s() → dynamic {
+    "1st";
+  }
+  static method f() → dynamic
+    return invalid-expression "pkg/front_end/testcases/general/duplicated_declarations.dart:64:17: Error: Can't use 's' because it is declared more than once.
+  static f() => s;
+                ^";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Sub extends core::Object {
+  constructor •() → self::Sub*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/duplicated_declarations.dart:68:16: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+  Sub() : super(null);
+               ^"
+    ;
+  method m() → dynamic
+    return super.m();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Enum#4 extends core::_Enum /*isEnum*/  { // from org-dartlang-testcase:///duplicated_declarations_part.dart
+  static const field core::List<self::Enum#4*>* values = #C4;
+  static const field self::Enum#4* a = #C3;
+  const constructor •(core::int* index, core::String* name) → self::Enum#4*
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String*
+    return "Enum#4.${this.{core::_Enum::_name}{core::String}}";
+  abstract member-signature get index() → core::int*; -> core::_Enum::index
+  abstract member-signature get _name() → core::String*; -> core::_Enum::_name
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Enum#3 extends core::_Enum /*isEnum*/  { // from org-dartlang-testcase:///duplicated_declarations_part.dart
+  static const field core::List<self::Enum#3*>* values = #C12;
+  static const field self::Enum#3* a = #C5;
+  static const field self::Enum#3* b = #C8;
+  static const field self::Enum#3* c = #C11;
+  const constructor •(core::int* index, core::String* name) → self::Enum#3*
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String*
+    return "Enum#3.${this.{core::_Enum::_name}{core::String}}";
+  abstract member-signature get index() → core::int*; -> core::_Enum::index
+  abstract member-signature get _name() → core::String*; -> core::_Enum::_name
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Enum#2 extends core::_Enum /*isEnum*/  { // from org-dartlang-testcase:///duplicated_declarations_part.dart
+  static const field core::List<self::Enum#2*>* values = #C17;
+  static const field self::Enum#2* Enum = #C14;
+  static const field self::Enum#2* a = #C15;
+  static const field self::Enum#2* b = #C16;
+  const constructor •(core::int* index, core::String* name) → self::Enum#2*
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String*
+    return "Enum#2.${this.{core::_Enum::_name}{core::String}}";
+  abstract member-signature get index() → core::int*; -> core::_Enum::index
+  abstract member-signature get _name() → core::String*; -> core::_Enum::_name
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Enum#1 extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::Enum#1*>* values = #C21;
+  static const field self::Enum#1* a = #C18;
+  static const field self::Enum#1* b = #C19;
+  static const field self::Enum#1* c = #C20;
+  const constructor •(core::int* index, core::String* name) → self::Enum#1*
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String*
+    return "Enum#1.${this.{core::_Enum::_name}{core::String}}";
+  abstract member-signature get index() → core::int*; -> core::_Enum::index
+  abstract member-signature get _name() → core::String*; -> core::_Enum::_name
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Enum extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::Enum*>* values = #C25;
+  static const field self::Enum* Enum = #C22;
+  static const field self::Enum* a = #C23;
+  static const field self::Enum* b = #C24;
+  const constructor •(core::int* index, core::String* name) → self::Enum*
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String*
+    return "Enum.${this.{core::_Enum::_name}{core::String}}";
+  abstract member-signature get index() → core::int*; -> core::_Enum::index
+  abstract member-signature get _name() → core::String*; -> core::_Enum::_name
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class AnotherEnum extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::AnotherEnum*>* values = #C35;
+  static const field self::AnotherEnum* a = #C26;
+  static const field self::AnotherEnum* b = #C27;
+  static const field self::AnotherEnum* c = #C28;
+  static const field self::AnotherEnum* _name = #C31;
+  static const field self::AnotherEnum* index = #C34;
+  const constructor •(core::int* index, core::String* name) → self::AnotherEnum*
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String*
+    return "AnotherEnum.${this.{core::_Enum::_name}{core::String}}";
+  abstract member-signature get _name() → core::String*; -> core::_Enum::_name
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::String* field;
+static method main() → dynamic {
+  "1st";
+}
+static method foo() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/duplicated_declarations.dart:34:3: Error: Can't use 'main' because it is declared more than once.
+  main();
+  ^"{dynamic}.call();
+  core::print(invalid-expression "pkg/front_end/testcases/general/duplicated_declarations.dart:35:9: Error: Can't use 'field' because it is declared more than once.
+  print(field);
+        ^");
+  invalid-expression "pkg/front_end/testcases/general/duplicated_declarations.dart:36:3: Error: Can't use 'C' because it is declared more than once.
+  C.s();
+  ^"{dynamic}.s();
+  invalid-expression "pkg/front_end/testcases/general/duplicated_declarations.dart:37:5: Error: Expected identifier, but got 'this'.
+  C.this();
+    ^^^^";
+  invalid-expression "pkg/front_end/testcases/general/duplicated_declarations.dart:38:5: Error: Expected an identifier, but got '('.
+Try inserting an identifier before '('.
+  C.();
+    ^";
+}
+static method useAnotherEnum() → dynamic {
+  <core::String*, core::Object*>{"AnotherEnum.a": #C26, "AnotherEnum.b": #C27, "AnotherEnum.c": #C28, "AnotherEnum._name": #C31, "AnotherEnum.index": #C34, "AnotherEnum.toString": invalid-expression "pkg/front_end/testcases/general/duplicated_declarations.dart:106:41: Error: Can't use 'toString' because it is declared more than once.
+    \"AnotherEnum.toString\": AnotherEnum.toString,
+                                        ^^^^^^^^", "AnotherEnum.values": invalid-expression "pkg/front_end/testcases/general/duplicated_declarations.dart:107:39: Error: Can't use 'values' because it is declared more than once.
+    \"AnotherEnum.values\": AnotherEnum.values,
+                                      ^^^^^^"};
+}
+
+library;
+import self as self2;
+
+
+constants  {
+  #C1 = 0
+  #C2 = "a"
+  #C3 = self::Enum#4 {index:#C1, _name:#C2}
+  #C4 = <self::Enum#4*>[#C3]
+  #C5 = self::Enum#3 {index:#C1, _name:#C2}
+  #C6 = 1
+  #C7 = "b"
+  #C8 = self::Enum#3 {index:#C6, _name:#C7}
+  #C9 = 2
+  #C10 = "c"
+  #C11 = self::Enum#3 {index:#C9, _name:#C10}
+  #C12 = <self::Enum#3*>[#C5, #C8, #C11]
+  #C13 = "Enum"
+  #C14 = self::Enum#2 {index:#C1, _name:#C13}
+  #C15 = self::Enum#2 {index:#C6, _name:#C2}
+  #C16 = self::Enum#2 {index:#C9, _name:#C7}
+  #C17 = <self::Enum#2*>[#C14, #C15, #C16]
+  #C18 = self::Enum#1 {index:#C1, _name:#C2}
+  #C19 = self::Enum#1 {index:#C6, _name:#C7}
+  #C20 = self::Enum#1 {index:#C9, _name:#C10}
+  #C21 = <self::Enum#1*>[#C18, #C19, #C20]
+  #C22 = self::Enum {index:#C1, _name:#C13}
+  #C23 = self::Enum {index:#C6, _name:#C2}
+  #C24 = self::Enum {index:#C9, _name:#C7}
+  #C25 = <self::Enum*>[#C22, #C23, #C24]
+  #C26 = self::AnotherEnum {index:#C1, _name:#C2}
+  #C27 = self::AnotherEnum {index:#C6, _name:#C7}
+  #C28 = self::AnotherEnum {index:#C9, _name:#C10}
+  #C29 = 3
+  #C30 = "_name"
+  #C31 = self::AnotherEnum {index:#C29, _name:#C30}
+  #C32 = 4
+  #C33 = "index"
+  #C34 = self::AnotherEnum {index:#C32, _name:#C33}
+  #C35 = <self::AnotherEnum*>[#C26, #C27, #C28, #C31, #C34]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///duplicated_declarations.dart:
+- Enum#1. (from org-dartlang-testcase:///duplicated_declarations.dart:83:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:76:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Enum. (from org-dartlang-testcase:///duplicated_declarations.dart:76:6)
+- AnotherEnum. (from org-dartlang-testcase:///duplicated_declarations.dart:89:6)
diff --git a/pkg/front_end/testcases/general/duplicated_field_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/general/duplicated_field_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..92572f2
--- /dev/null
+++ b/pkg/front_end/testcases/general/duplicated_field_initializer.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/duplicated_field_initializer.dart:7:7: Error: 'a' is already declared in this scope.
+//   int a;
+//       ^
+// pkg/front_end/testcases/general/duplicated_field_initializer.dart:6:7: Context: Previous declaration of 'a'.
+//   int a;
+//       ^
+//
+// pkg/front_end/testcases/general/duplicated_field_initializer.dart:8:10: Error: Can't use 'a' because it is declared more than once.
+//   A(this.a);
+//          ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* a = null;
+  constructor •(core::int* a) → self::A*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/duplicated_field_initializer.dart:8:10: Error: Can't use 'a' because it is declared more than once.
+  A(this.a);
+         ^"
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {
+  new self::A::•(1);
+}
diff --git a/pkg/front_end/testcases/general/duplicated_named_args_3.dart.weak.modular.expect b/pkg/front_end/testcases/general/duplicated_named_args_3.dart.weak.modular.expect
new file mode 100644
index 0000000..d6d8288
--- /dev/null
+++ b/pkg/front_end/testcases/general/duplicated_named_args_3.dart.weak.modular.expect
@@ -0,0 +1,47 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/duplicated_named_args_3.dart:13:13: Error: Duplicated named argument 'a'.
+//   C.m(a: 1, a: 2, a: 3);
+//             ^
+//
+// pkg/front_end/testcases/general/duplicated_named_args_3.dart:13:19: Error: Duplicated named argument 'a'.
+//   C.m(a: 1, a: 2, a: 3);
+//                   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  static method m({core::int* a = #C1}) → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → void {
+  self::C::m(a: invalid-expression "pkg/front_end/testcases/general/duplicated_named_args_3.dart:13:19: Error: Duplicated named argument 'a'.
+  C.m(a: 1, a: 2, a: 3);
+                  ^" in block {
+    invalid-expression "pkg/front_end/testcases/general/duplicated_named_args_3.dart:13:13: Error: Duplicated named argument 'a'.
+  C.m(a: 1, a: 2, a: 3);
+            ^" in block {
+      1;
+    } =>2;
+  } =>3);
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+}
diff --git a/pkg/front_end/testcases/general/dynamic_and_void.dart.weak.modular.expect b/pkg/front_end/testcases/general/dynamic_and_void.dart.weak.modular.expect
new file mode 100644
index 0000000..c400faa
--- /dev/null
+++ b/pkg/front_end/testcases/general/dynamic_and_void.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/dynamic_and_void.dart:10:1: Error: Type 'dynamic' not found.
+// dynamic testDynamic() => 0;
+// ^^^^^^^
+//
+import self as self;
+
+import "dart:core" show int;
+
+static method testDynamic() → invalid-type
+  return 0;
+static method testVoid() → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/enum_names_from_core.dart.weak.modular.expect b/pkg/front_end/testcases/general/enum_names_from_core.dart.weak.modular.expect
new file mode 100644
index 0000000..f367499
--- /dev/null
+++ b/pkg/front_end/testcases/general/enum_names_from_core.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class int extends core::Object {
+  synthetic constructor •() → self::int
+    : super core::Object::•()
+    ;
+}
+class Object extends core::Object {
+  synthetic constructor •() → self::Object
+    : super core::Object::•()
+    ;
+}
+class String extends core::Object {
+  synthetic constructor •() → self::String
+    : super core::Object::•()
+    ;
+}
+class _Enum extends core::Object {
+  synthetic constructor •() → self::_Enum
+    : super core::Object::•()
+    ;
+}
+class List extends core::Object {
+  synthetic constructor •() → self::List
+    : super core::Object::•()
+    ;
+}
+class E extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::E> values = #C16;
+  static const field self::E int = #C3;
+  static const field self::E Object = #C6;
+  static const field self::E String = #C9;
+  static const field self::E _Enum = #C12;
+  static const field self::E List = #C15;
+  const constructor •(core::int index, core::String name) → self::E
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String
+    return "E.${this.{core::_Enum::_name}{core::String}}";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+  #C2 = "int"
+  #C3 = self::E {index:#C1, _name:#C2}
+  #C4 = 1
+  #C5 = "Object"
+  #C6 = self::E {index:#C4, _name:#C5}
+  #C7 = 2
+  #C8 = "String"
+  #C9 = self::E {index:#C7, _name:#C8}
+  #C10 = 3
+  #C11 = "_Enum"
+  #C12 = self::E {index:#C10, _name:#C11}
+  #C13 = 4
+  #C14 = "List"
+  #C15 = self::E {index:#C13, _name:#C14}
+  #C16 = <self::E*>[#C3, #C6, #C9, #C12, #C15]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///enum_names_from_core.dart:
+- E. (from org-dartlang-testcase:///enum_names_from_core.dart:15:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:76:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/error_locations/error_location_01.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_locations/error_location_01.dart.weak.modular.expect
new file mode 100644
index 0000000..a1e0f80
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_locations/error_location_01.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library;
+import self as self;
+import "error_location_01_lib1.dart" as err;
+import "error_location_01_lib2.dart" as err2;
+
+import "org-dartlang-testcase:///error_location_01_lib1.dart";
+import "org-dartlang-testcase:///error_location_01_lib2.dart";
+
+static method main() → dynamic {
+  err::foo();
+  err2::bar();
+}
+
+library;
+import self as err;
+import "dart:core" as core;
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  const constructor •(core::int* i) → err::Foo*
+    : assert(i.{core::num::>}(0){(core::num*) →* core::bool*}), super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo() → dynamic {
+  new err::Foo::•(0);
+}
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_locations/error_location_01_lib2.dart:8:9: Error: Constant evaluation error:
+//   const Foo(0);
+//         ^
+// pkg/front_end/testcases/general/error_locations/error_location_01_lib1.dart:6:31: Context: This assertion failed.
+//   const Foo(int i) : assert(i > 0);
+//                               ^
+//
+import self as err2;
+
+import "org-dartlang-testcase:///error_location_01_lib1.dart";
+
+static method bar() → dynamic {
+  invalid-expression "This assertion failed.";
+}
+
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///error_location_01_lib2.dart:
+- Foo. (from org-dartlang-testcase:///error_location_01_lib1.dart:6:9)
diff --git a/pkg/front_end/testcases/general/error_locations/error_location_02.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_locations/error_location_02.dart.weak.modular.expect
new file mode 100644
index 0000000..4b68f2c
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_locations/error_location_02.dart.weak.modular.expect
@@ -0,0 +1,84 @@
+library;
+import self as self;
+import "error_location_02_lib1.dart" as err;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///error_location_02_lib1.dart";
+import "org-dartlang-testcase:///error_location_02_lib2.dart";
+import "org-dartlang-testcase:///error_location_02_lib3.dart";
+
+static method main() → dynamic {
+  err::foo();
+  core::print(invalid-expression "This assertion failed.");
+}
+
+library;
+import self as err;
+import "dart:core" as core;
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  const constructor •(core::int* i) → err::Foo*
+    : assert(i.{core::num::>}(0){(core::num*) →* core::bool*}), super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo() → dynamic {
+  new err::Foo::•(0);
+}
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_locations/error_location_02_lib2.dart:7:24: Error: Constant evaluation error:
+// const fooField = const Foo(0);
+//                        ^
+// pkg/front_end/testcases/general/error_locations/error_location_02_lib1.dart:6:31: Context: This assertion failed.
+//   const Foo(int i) : assert(i > 0);
+//                               ^
+// pkg/front_end/testcases/general/error_locations/error_location_02_lib2.dart:7:7: Context: While analyzing:
+// const fooField = const Foo(0);
+//       ^
+//
+import self as self2;
+import "error_location_02_lib1.dart" as err;
+
+import "org-dartlang-testcase:///error_location_02_lib1.dart";
+
+static const field err::Foo* fooField = invalid-expression "This assertion failed.";
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_locations/error_location_02_lib3.dart:7:19: Error: Constant evaluation error:
+// const fooField2 = fooField;
+//                   ^
+// pkg/front_end/testcases/general/error_locations/error_location_02_lib1.dart:6:31: Context: This assertion failed.
+//   const Foo(int i) : assert(i > 0);
+//                               ^
+// pkg/front_end/testcases/general/error_locations/error_location_02_lib3.dart:7:7: Context: While analyzing:
+// const fooField2 = fooField;
+//       ^
+//
+import self as self3;
+import "error_location_02_lib1.dart" as err;
+
+import "org-dartlang-testcase:///error_location_02_lib2.dart";
+
+static const field err::Foo* fooField2 = invalid-expression "This assertion failed.";
+
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///error_location_02_lib2.dart:
+- Foo. (from org-dartlang-testcase:///error_location_02_lib1.dart:6:9)
diff --git a/pkg/front_end/testcases/general/error_locations/error_location_03.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_locations/error_location_03.dart.weak.modular.expect
new file mode 100644
index 0000000..a11cbcd
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_locations/error_location_03.dart.weak.modular.expect
@@ -0,0 +1,88 @@
+library;
+import self as self;
+import "error_location_03_lib1.dart" as err;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///error_location_03_lib1.dart";
+import "org-dartlang-testcase:///error_location_03_lib2.dart";
+import "org-dartlang-testcase:///error_location_03_lib3.dart";
+
+static method main() → dynamic {
+  err::foo();
+  core::print(invalid-expression "This assertion failed.");
+  core::print(invalid-expression "This assertion failed.");
+}
+
+library;
+import self as err;
+import "dart:core" as core;
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  const constructor •(core::int* i) → err::Foo*
+    : assert(i.{core::num::>}(0){(core::num*) →* core::bool*}), super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo() → dynamic {
+  new err::Foo::•(0);
+}
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_locations/error_location_03_lib2.dart:7:24: Error: Constant evaluation error:
+// const fooField = const Foo(0);
+//                        ^
+// pkg/front_end/testcases/general/error_locations/error_location_03_lib1.dart:6:31: Context: This assertion failed.
+//   const Foo(int i) : assert(i > 0);
+//                               ^
+// pkg/front_end/testcases/general/error_locations/error_location_03_lib2.dart:7:7: Context: While analyzing:
+// const fooField = const Foo(0);
+//       ^
+//
+import self as self2;
+import "error_location_03_lib1.dart" as err;
+
+import "org-dartlang-testcase:///error_location_03_lib1.dart";
+
+static const field err::Foo* fooField = invalid-expression "This assertion failed.";
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_locations/error_location_03_lib3.dart:7:25: Error: Constant evaluation error:
+// const fooField2 = const Foo(0);
+//                         ^
+// pkg/front_end/testcases/general/error_locations/error_location_03_lib1.dart:6:31: Context: This assertion failed.
+//   const Foo(int i) : assert(i > 0);
+//                               ^
+// pkg/front_end/testcases/general/error_locations/error_location_03_lib3.dart:7:7: Context: While analyzing:
+// const fooField2 = const Foo(0);
+//       ^
+//
+import self as self3;
+import "error_location_03_lib1.dart" as err;
+
+import "org-dartlang-testcase:///error_location_03_lib1.dart";
+
+static const field err::Foo* fooField2 = invalid-expression "This assertion failed.";
+
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///error_location_03_lib2.dart:
+- Foo. (from org-dartlang-testcase:///error_location_03_lib1.dart:6:9)
+
+org-dartlang-testcase:///error_location_03_lib3.dart:
+- Foo. (from org-dartlang-testcase:///error_location_03_lib1.dart:6:9)
diff --git a/pkg/front_end/testcases/general/error_locations/error_location_04.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_locations/error_location_04.dart.weak.modular.expect
new file mode 100644
index 0000000..32f4daa
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_locations/error_location_04.dart.weak.modular.expect
@@ -0,0 +1,76 @@
+library;
+import self as self;
+import "error_location_04_lib1.dart" as err;
+import "error_location_04_lib2.dart" as err2;
+
+import "org-dartlang-testcase:///error_location_04_lib1.dart";
+import "org-dartlang-testcase:///error_location_04_lib2.dart";
+
+static method main() → dynamic {
+  err::foo();
+  err2::bar();
+}
+
+library;
+import self as err;
+import "dart:core" as core;
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  const constructor •(core::int* i) → err::Foo*
+    : assert(i.{core::num::>}(0){(core::num*) →* core::bool*}), super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo() → dynamic {
+  new err::Foo::•(0);
+}
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_locations/error_location_04_lib2.dart:9:27: Error: Constant evaluation error:
+//   const Bar() : x = const Foo(0);
+//                           ^
+// pkg/front_end/testcases/general/error_locations/error_location_04_lib1.dart:6:31: Context: This assertion failed.
+//   const Foo(int i) : assert(i > 0);
+//                               ^
+//
+import self as err2;
+import "dart:core" as core;
+import "error_location_04_lib1.dart" as err;
+
+import "org-dartlang-testcase:///error_location_04_lib1.dart";
+
+class Bar extends core::Object /*hasConstConstructor*/  {
+  final field err::Foo* x;
+  const constructor •() → err2::Bar*
+    : err2::Bar::x = invalid-expression "This assertion failed.", super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method bar() → dynamic {}
+
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///error_location_04_lib2.dart:
+- Foo. (from org-dartlang-testcase:///error_location_04_lib1.dart:6:9)
diff --git a/pkg/front_end/testcases/general/error_locations/error_location_05.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_locations/error_location_05.dart.weak.modular.expect
new file mode 100644
index 0000000..c53238d
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_locations/error_location_05.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library error_location_05;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_locations/error_location_05_lib1.dart:7:8: Error: Duplicated parameter name 'z'.
+// x1(z, {z}) {}
+//        ^
+// pkg/front_end/testcases/general/error_locations/error_location_05_lib1.dart:7:4: Context: Other parameter named 'z'.
+// x1(z, {z}) {}
+//    ^
+//
+// pkg/front_end/testcases/general/error_locations/error_location_05_lib1.dart:10:9: Error: 'z' is already declared in this scope.
+//   y(z, {z}) {}
+//         ^
+// pkg/front_end/testcases/general/error_locations/error_location_05_lib1.dart:10:5: Context: Previous declaration of 'z'.
+//   y(z, {z}) {}
+//     ^
+//
+import self as self;
+
+part error_location_05_lib1.dart;
+static method /* from org-dartlang-testcase:///error_location_05_lib1.dart */ x1(dynamic z, {dynamic z = #C1}) → dynamic {}
+static method /* from org-dartlang-testcase:///error_location_05_lib1.dart */ x2() → dynamic {
+  function y(dynamic z, {dynamic z = #C1}) → Null {}
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/error_locations/error_location_06.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_locations/error_location_06.dart.weak.modular.expect
new file mode 100644
index 0000000..de18361
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_locations/error_location_06.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library error_location_06;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_locations/error_location_06_lib1.dart:12:8: Error: Duplicated parameter name 'z'.
+// x1(z, {z}) {}
+//        ^
+// pkg/front_end/testcases/general/error_locations/error_location_06_lib1.dart:12:4: Context: Other parameter named 'z'.
+// x1(z, {z}) {}
+//    ^
+//
+// pkg/front_end/testcases/general/error_locations/error_location_06_lib1.dart:15:9: Error: 'z' is already declared in this scope.
+//   y(z, {z}) {}
+//         ^
+// pkg/front_end/testcases/general/error_locations/error_location_06_lib1.dart:15:5: Context: Previous declaration of 'z'.
+//   y(z, {z}) {}
+//     ^
+//
+import self as self;
+
+part error_location_06_lib1.dart;
+static method /* from org-dartlang-testcase:///error_location_06_lib1.dart */ x1(dynamic z, {dynamic z = #C1}) → dynamic {}
+static method /* from org-dartlang-testcase:///error_location_06_lib1.dart */ x2() → dynamic {
+  function y(dynamic z, {dynamic z = #C1}) → Null {}
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/annotations.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/annotations.dart.weak.modular.expect
new file mode 100644
index 0000000..c6d3c9f
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/annotations.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/annotations.dart:15:16: Error: Type arguments can't have annotations because they aren't declarations.
+//   m() => new A<@annotation @Annotation("test") C>();
+//                ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/annotations.dart:15:28: Error: Type arguments can't have annotations because they aren't declarations.
+//   m() => new A<@annotation @Annotation("test") C>();
+//                            ^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Annotation extends core::Object /*hasConstConstructor*/  {
+  final field core::String* message;
+  const constructor •(core::String* message) → self::Annotation*
+    : self::Annotation::message = message, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A<E extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::E*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method m() → dynamic
+    return new self::A::•<self::C*>();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field dynamic annotation = #C1;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/await_not_in_async.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/await_not_in_async.dart.weak.modular.expect
new file mode 100644
index 0000000..12f76fb
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/await_not_in_async.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/await_not_in_async.dart:4:3: Error: 'await' can only be used in 'async' or 'async*' methods.
+//   await f();
+//   ^^^^^
+//
+import self as self;
+import "dart:async" as asy;
+
+static method f() → asy::Future<void>
+  return asy::Future::value<void>();
+static method g() → void {
+  invalid-expression "pkg/front_end/testcases/general/error_recovery/await_not_in_async.dart:4:3: Error: 'await' can only be used in 'async' or 'async*' methods.
+  await f();
+  ^^^^^";
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..17c2eb1
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart.weak.modular.expect
@@ -0,0 +1,377 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:2:3: Error: The name of a constructor must match the name of the enclosing class.
+//   foo.x() {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:5:3: Error: The name of a constructor must match the name of the enclosing class.
+//   foo.x() : initializer = true {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:5:3: Error: 'Foo.x' is already declared in this scope.
+//   foo.x() : initializer = true {
+//   ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:2:3: Context: Previous declaration of 'Foo.x'.
+//   foo.x() {
+//   ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:8:3: Error: The name of a constructor must match the name of the enclosing class.
+//   foo() : initializer = true {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:11:7: Error: A class member can't have the same name as the enclosing class.
+// Try renaming the member.
+//   get Foo => 0;
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:12:7: Error: A class member can't have the same name as the enclosing class.
+// Try renaming the member.
+//   get Foo {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:12:7: Error: 'Foo' is already declared in this scope.
+//   get Foo {
+//       ^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:11:7: Context: Previous declaration of 'Foo'.
+//   get Foo => 0;
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:15:7: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   get Foo.X => 0;
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:15:3: Error: Constructors can't be a getter.
+// Try removing 'get'.
+//   get Foo.X => 0;
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:16:7: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   get Foo.X {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:16:3: Error: Constructors can't be a getter.
+// Try removing 'get'.
+//   get Foo.X {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:16:7: Error: 'Foo.X' is already declared in this scope.
+//   get Foo.X {
+//       ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:15:7: Context: Previous declaration of 'Foo.X'.
+//   get Foo.X => 0;
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:19:7: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   get Foo : bla = null => 0;
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:19:3: Error: Constructors can't be a getter.
+// Try removing 'get'.
+//   get Foo : bla = null => 0;
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:20:7: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   get Foo.X : bla = null {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:20:3: Error: Constructors can't be a getter.
+// Try removing 'get'.
+//   get Foo.X : bla = null {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:20:7: Error: 'Foo.X' is already declared in this scope.
+//   get Foo.X : bla = null {
+//       ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:16:7: Context: Previous declaration of 'Foo.X'.
+//   get Foo.X {
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:23:7: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   set Foo => 0;
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:23:7: Error: A class member can't have the same name as the enclosing class.
+// Try renaming the member.
+//   set Foo => 0;
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:24:7: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   set Foo {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:24:7: Error: A class member can't have the same name as the enclosing class.
+// Try renaming the member.
+//   set Foo {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:24:7: Error: 'Foo' is already declared in this scope.
+//   set Foo {
+//       ^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:23:7: Context: Previous declaration of 'Foo'.
+//   set Foo => 0;
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:27:7: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   set Foo.X => 0;
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:27:3: Error: Constructors can't be a setter.
+// Try removing 'set'.
+//   set Foo.X => 0;
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:27:7: Error: 'Foo.X' is already declared in this scope.
+//   set Foo.X => 0;
+//       ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:20:7: Context: Previous declaration of 'Foo.X'.
+//   get Foo.X : bla = null {
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:28:7: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   set Foo.X {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:28:3: Error: Constructors can't be a setter.
+// Try removing 'set'.
+//   set Foo.X {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:28:7: Error: 'Foo.X' is already declared in this scope.
+//   set Foo.X {
+//       ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:27:7: Context: Previous declaration of 'Foo.X'.
+//   set Foo.X => 0;
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:31:7: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   set Foo : bla = null => 0;
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:31:3: Error: Constructors can't be a setter.
+// Try removing 'set'.
+//   set Foo : bla = null => 0;
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:31:7: Error: 'Foo' is already declared in this scope.
+//   set Foo : bla = null => 0;
+//       ^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:19:7: Context: Previous declaration of 'Foo'.
+//   get Foo : bla = null => 0;
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:32:7: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   set Foo.X : bla = null {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:32:3: Error: Constructors can't be a setter.
+// Try removing 'set'.
+//   set Foo.X : bla = null {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:32:7: Error: 'Foo.X' is already declared in this scope.
+//   set Foo.X : bla = null {
+//       ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:28:7: Context: Previous declaration of 'Foo.X'.
+//   set Foo.X {
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:35:18: Error: An external constructor can't have any initializers.
+//   external Foo() : bla = null;
+//                  ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:35:12: Error: 'Foo' is already declared in this scope.
+//   external Foo() : bla = null;
+//            ^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:31:7: Context: Previous declaration of 'Foo'.
+//   set Foo : bla = null => 0;
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:36:33: Error: An external or native method can't have a body.
+//   external Foo.X() : bla = null {
+//                                 ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:36:20: Error: An external constructor can't have any initializers.
+//   external Foo.X() : bla = null {
+//                    ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:36:12: Error: 'Foo.X' is already declared in this scope.
+//   external Foo.X() : bla = null {
+//            ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:32:7: Context: Previous declaration of 'Foo.X'.
+//   set Foo.X : bla = null {
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:39:7: Error: A class member can't have the same name as the enclosing class.
+// Try renaming the member.
+//   int Foo;
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:39:7: Error: 'Foo' is already declared in this scope.
+//   int Foo;
+//       ^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:12:7: Context: Previous declaration of 'Foo'.
+//   get Foo {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:40:10: Error: A class member can't have the same name as the enclosing class.
+// Try renaming the member.
+//   int A, Foo, B;
+//          ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:40:10: Error: 'Foo' is already declared in this scope.
+//   int A, Foo, B;
+//          ^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:39:7: Context: Previous declaration of 'Foo'.
+//   int Foo;
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:24:7: Error: Conflicts with the implicit setter of the field 'Foo'.
+//   set Foo {
+//       ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:23:7: Error: Conflicts with the implicit setter of the field 'Foo'.
+//   set Foo => 0;
+//       ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:40:10: Error: Conflicts with setter 'Foo'.
+//   int A, Foo, B;
+//          ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:39:7: Error: Conflicts with setter 'Foo'.
+//   int Foo;
+//       ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:5:13: Error: 'initializer' isn't an instance field of this class.
+//   foo.x() : initializer = true {
+//             ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:8:11: Error: 'initializer' isn't an instance field of this class.
+//   foo() : initializer = true {
+//           ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:15:16: Error: Constructors can't have a return type.
+// Try removing the return type.
+//   get Foo.X => 0;
+//                ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:17:5: Error: Constructors can't have a return type.
+// Try removing the return type.
+//     return 0;
+//     ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:19:13: Error: 'bla' isn't an instance field of this class.
+//   get Foo : bla = null => 0;
+//             ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:19:27: Error: Constructors can't have a return type.
+// Try removing the return type.
+//   get Foo : bla = null => 0;
+//                           ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:20:15: Error: 'bla' isn't an instance field of this class.
+//   get Foo.X : bla = null {
+//               ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:21:5: Error: Constructors can't have a return type.
+// Try removing the return type.
+//     return 0;
+//     ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:23:11: Error: A setter should have exactly one formal parameter.
+//   set Foo => 0;
+//           ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:25:12: Error: Can't return a value from a void function.
+//     return 0;
+//            ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:24:11: Error: A setter should have exactly one formal parameter.
+//   set Foo {
+//           ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:27:16: Error: Constructors can't have a return type.
+// Try removing the return type.
+//   set Foo.X => 0;
+//                ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:29:5: Error: Constructors can't have a return type.
+// Try removing the return type.
+//     return 0;
+//     ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:31:13: Error: 'bla' isn't an instance field of this class.
+//   set Foo : bla = null => 0;
+//             ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:31:27: Error: Constructors can't have a return type.
+// Try removing the return type.
+//   set Foo : bla = null => 0;
+//                           ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:32:15: Error: 'bla' isn't an instance field of this class.
+//   set Foo.X : bla = null {
+//               ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:33:5: Error: Constructors can't have a return type.
+// Try removing the return type.
+//     return 0;
+//     ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:37:5: Error: Constructors can't have a return type.
+// Try removing the return type.
+//     return 0;
+//     ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:39:7: Error: Field 'Foo' should be initialized because its type 'int' doesn't allow null.
+//   int Foo;
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:40:7: Error: Field 'A' should be initialized because its type 'int' doesn't allow null.
+//   int A, Foo, B;
+//       ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:40:15: Error: Field 'B' should be initialized because its type 'int' doesn't allow null.
+//   int A, Foo, B;
+//               ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  field core::int A = null;
+  field core::int B = null;
+  constructor x() → self::Foo
+    : super core::Object::•() {}
+  constructor foo() → self::Foo
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:8:11: Error: 'initializer' isn't an instance field of this class.
+  foo() : initializer = true {
+          ^^^^^^^^^^^" {}
+  constructor X() → self::Foo
+    : super core::Object::•()
+    invalid-expression "pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:15:16: Error: Constructors can't have a return type.
+Try removing the return type.
+  get Foo.X => 0;
+               ^";
+  constructor •() → self::Foo
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:19:13: Error: 'bla' isn't an instance field of this class.
+  get Foo : bla = null => 0;
+            ^^^"
+    invalid-expression "pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_general.crash_dart:19:27: Error: Constructors can't have a return type.
+Try removing the return type.
+  get Foo : bla = null => 0;
+                          ^";
+  get Foo() → dynamic
+    return 0;
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_get.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_get.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..4435554
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_get.crash_dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_get.crash_dart:2:7: Error: The name of a constructor must match the name of the enclosing class.
+//   get foo.x() {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_get.crash_dart:2:3: Error: Constructors can't be a getter.
+// Try removing 'get'.
+//   get foo.x() {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_get.crash_dart:5:7: Error: The name of a constructor must match the name of the enclosing class.
+//   get foo.x() : initializer = true {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_get.crash_dart:5:3: Error: Constructors can't be a getter.
+// Try removing 'get'.
+//   get foo.x() : initializer = true {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_get.crash_dart:5:7: Error: 'Foo.x' is already declared in this scope.
+//   get foo.x() : initializer = true {
+//       ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_get.crash_dart:2:7: Context: Previous declaration of 'Foo.x'.
+//   get foo.x() {
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_get.crash_dart:8:10: Error: A getter can't have formal parameters.
+// Try removing '(...)'.
+//   get foo() : initializer = true {
+//          ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_get.crash_dart:8:7: Error: The name of a constructor must match the name of the enclosing class.
+//   get foo() : initializer = true {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_get.crash_dart:8:3: Error: Constructors can't be a getter.
+// Try removing 'get'.
+//   get foo() : initializer = true {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_get.crash_dart:5:17: Error: 'initializer' isn't an instance field of this class.
+//   get foo.x() : initializer = true {
+//                 ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_get.crash_dart:8:15: Error: 'initializer' isn't an instance field of this class.
+//   get foo() : initializer = true {
+//               ^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  constructor x() → self::Foo
+    : super core::Object::•() {}
+  constructor foo() → self::Foo
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_get.crash_dart:8:15: Error: 'initializer' isn't an instance field of this class.
+  get foo() : initializer = true {
+              ^^^^^^^^^^^" {}
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_return_type.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_return_type.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..ef13e6b
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_return_type.crash_dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_return_type.crash_dart:2:8: Error: The name of a constructor must match the name of the enclosing class.
+//   void foo.x() {
+//        ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_return_type.crash_dart:2:3: Error: Constructors can't have a return type.
+// Try removing the return type.
+//   void foo.x() {
+//   ^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_return_type.crash_dart:5:8: Error: The name of a constructor must match the name of the enclosing class.
+//   void foo.x() : initializer = true {
+//        ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_return_type.crash_dart:5:3: Error: Constructors can't have a return type.
+// Try removing the return type.
+//   void foo.x() : initializer = true {
+//   ^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_return_type.crash_dart:5:8: Error: 'Foo.x' is already declared in this scope.
+//   void foo.x() : initializer = true {
+//        ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_return_type.crash_dart:2:8: Context: Previous declaration of 'Foo.x'.
+//   void foo.x() {
+//        ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_return_type.crash_dart:8:8: Error: The name of a constructor must match the name of the enclosing class.
+//   void foo() : initializer = true {
+//        ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_return_type.crash_dart:8:3: Error: Constructors can't have a return type.
+// Try removing the return type.
+//   void foo() : initializer = true {
+//   ^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_return_type.crash_dart:5:18: Error: 'initializer' isn't an instance field of this class.
+//   void foo.x() : initializer = true {
+//                  ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_return_type.crash_dart:8:16: Error: 'initializer' isn't an instance field of this class.
+//   void foo() : initializer = true {
+//                ^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  constructor x() → self::Foo
+    : super core::Object::•() {}
+  constructor foo() → self::Foo
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_return_type.crash_dart:8:16: Error: 'initializer' isn't an instance field of this class.
+  void foo() : initializer = true {
+               ^^^^^^^^^^^" {}
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_set.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_set.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..583688c
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_set.crash_dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_set.crash_dart:2:7: Error: The name of a constructor must match the name of the enclosing class.
+//   set foo.x() {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_set.crash_dart:2:3: Error: Constructors can't be a setter.
+// Try removing 'set'.
+//   set foo.x() {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_set.crash_dart:5:7: Error: The name of a constructor must match the name of the enclosing class.
+//   set foo.x() : initializer = true {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_set.crash_dart:5:3: Error: Constructors can't be a setter.
+// Try removing 'set'.
+//   set foo.x() : initializer = true {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_set.crash_dart:5:7: Error: 'Foo.x' is already declared in this scope.
+//   set foo.x() : initializer = true {
+//       ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_set.crash_dart:2:7: Context: Previous declaration of 'Foo.x'.
+//   set foo.x() {
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_set.crash_dart:8:7: Error: The name of a constructor must match the name of the enclosing class.
+//   set foo() : initializer = true {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_set.crash_dart:8:3: Error: Constructors can't be a setter.
+// Try removing 'set'.
+//   set foo() : initializer = true {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_set.crash_dart:5:17: Error: 'initializer' isn't an instance field of this class.
+//   set foo.x() : initializer = true {
+//                 ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_set.crash_dart:8:15: Error: 'initializer' isn't an instance field of this class.
+//   set foo() : initializer = true {
+//               ^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  constructor x() → self::Foo
+    : super core::Object::•() {}
+  constructor foo() → self::Foo
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/error_recovery/constructor_recovery_bad_name_set.crash_dart:8:15: Error: 'initializer' isn't an instance field of this class.
+  set foo() : initializer = true {
+              ^^^^^^^^^^^" {}
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/constructor_recovery_get.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_get.dart.weak.modular.expect
new file mode 100644
index 0000000..eea597e
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_get.dart.weak.modular.expect
@@ -0,0 +1,71 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_get.dart:3:10: Error: A getter can't have formal parameters.
+// Try removing '(...)'.
+//   get Foo() {
+//          ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_get.dart:3:7: Error: A class member can't have the same name as the enclosing class.
+// Try renaming the member.
+//   get Foo() {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_get.dart:6:10: Error: A getter can't have formal parameters.
+// Try removing '(...)'.
+//   get Foo() : initializer = true {
+//          ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_get.dart:6:3: Error: Constructors can't be a getter.
+// Try removing 'get'.
+//   get Foo() : initializer = true {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_get.dart:9:3: Error: Constructors can't be a getter.
+// Try removing 'get'.
+//   get Foo.x() {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_get.dart:12:3: Error: Constructors can't be a getter.
+// Try removing 'get'.
+//   get Foo.x() : initializer = true {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_get.dart:12:7: Error: 'Foo.x' is already declared in this scope.
+//   get Foo.x() : initializer = true {
+//       ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_get.dart:9:7: Context: Previous declaration of 'Foo.x'.
+//   get Foo.x() {
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_get.dart:6:15: Error: 'initializer' isn't an instance field of this class.
+//   get Foo() : initializer = true {
+//               ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_get.dart:12:17: Error: 'initializer' isn't an instance field of this class.
+//   get Foo.x() : initializer = true {
+//                 ^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  constructor •() → self::Foo*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/error_recovery/constructor_recovery_get.dart:6:15: Error: 'initializer' isn't an instance field of this class.
+  get Foo() : initializer = true {
+              ^^^^^^^^^^^" {}
+  constructor x() → self::Foo*
+    : super core::Object::•() {}
+  get Foo() → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/constructor_recovery_ok.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_ok.dart.weak.modular.expect
new file mode 100644
index 0000000..92284b0
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_ok.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_ok.dart:6:3: Error: 'Foo' is already declared in this scope.
+//   Foo() : initializer = true {
+//   ^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_ok.dart:3:3: Context: Previous declaration of 'Foo'.
+//   Foo() {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_ok.dart:12:3: Error: 'Foo.x' is already declared in this scope.
+//   Foo.x() : initializer = true {
+//   ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_ok.dart:9:3: Context: Previous declaration of 'Foo.x'.
+//   Foo.x() {
+//   ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_ok.dart:6:11: Error: 'initializer' isn't an instance field of this class.
+//   Foo() : initializer = true {
+//           ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_ok.dart:12:13: Error: 'initializer' isn't an instance field of this class.
+//   Foo.x() : initializer = true {
+//             ^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  constructor •() → self::Foo*
+    : super core::Object::•() {}
+  constructor x() → self::Foo*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..7267317
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart.weak.modular.expect
@@ -0,0 +1,145 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:2:9: Error: Expected '{' before this.
+//   Foo() / : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:2:9: Error: Operator declarations must be preceded by the keyword 'operator'.
+// Try adding the keyword 'operator'.
+//   Foo() / : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:2:9: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   Foo() / : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:2:9: Error: The name of a constructor must match the name of the enclosing class.
+//   Foo() / : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:2:9: Error: Operator '/' should have exactly one parameter.
+//   Foo() / : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:5:8: Error: Expected '{' before this.
+//   Foo()./ : super() {
+//        ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:5:3: Error: 'Foo' is already declared in this scope.
+//   Foo()./ : super() {
+//   ^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:2:3: Context: Previous declaration of 'Foo'.
+//   Foo() / : super() {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:5:8: Error: Expected a class member, but got '.'.
+//   Foo()./ : super() {
+//        ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:5:9: Error: Operator declarations must be preceded by the keyword 'operator'.
+// Try adding the keyword 'operator'.
+//   Foo()./ : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:5:9: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   Foo()./ : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:5:9: Error: The name of a constructor must match the name of the enclosing class.
+//   Foo()./ : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:5:9: Error: Operator '/' should have exactly one parameter.
+//   Foo()./ : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:5:9: Error: 'Foo./' is already declared in this scope.
+//   Foo()./ : super() {
+//         ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:2:9: Context: Previous declaration of 'Foo./'.
+//   Foo() / : super() {
+//         ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:8:9: Error: Expected '{' before this.
+//   foo() / : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:8:9: Error: Operator declarations must be preceded by the keyword 'operator'.
+// Try adding the keyword 'operator'.
+//   foo() / : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:8:9: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   foo() / : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:8:9: Error: The name of a constructor must match the name of the enclosing class.
+//   foo() / : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:8:9: Error: Operator '/' should have exactly one parameter.
+//   foo() / : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:8:9: Error: 'Foo./' is already declared in this scope.
+//   foo() / : super() {
+//         ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:5:9: Context: Previous declaration of 'Foo./'.
+//   Foo()./ : super() {
+//         ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:11:8: Error: Expected '{' before this.
+//   foo()./ : super() {
+//        ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:11:3: Error: 'foo' is already declared in this scope.
+//   foo()./ : super() {
+//   ^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:8:3: Context: Previous declaration of 'foo'.
+//   foo() / : super() {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:11:8: Error: Expected a class member, but got '.'.
+//   foo()./ : super() {
+//        ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:11:9: Error: Operator declarations must be preceded by the keyword 'operator'.
+// Try adding the keyword 'operator'.
+//   foo()./ : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:11:9: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   foo()./ : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:11:9: Error: The name of a constructor must match the name of the enclosing class.
+//   foo()./ : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:11:9: Error: Operator '/' should have exactly one parameter.
+//   foo()./ : super() {
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:11:9: Error: 'Foo./' is already declared in this scope.
+//   foo()./ : super() {
+//         ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_operator.crash_dart:8:9: Context: Previous declaration of 'Foo./'.
+//   foo() / : super() {
+//         ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  constructor •() → self::Foo
+    : super core::Object::•() {}
+  constructor /() → self::Foo
+    : super core::Object::•() {}
+  method foo() → dynamic {}
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/constructor_recovery_return_type.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_return_type.dart.weak.modular.expect
new file mode 100644
index 0000000..b038f45e2
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_return_type.dart.weak.modular.expect
@@ -0,0 +1,65 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_return_type.dart:3:3: Error: Constructors can't have a return type.
+// Try removing the return type.
+//   void Foo() {
+//   ^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_return_type.dart:6:3: Error: Constructors can't have a return type.
+// Try removing the return type.
+//   void Foo() : initializer = true {
+//   ^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_return_type.dart:6:8: Error: 'Foo' is already declared in this scope.
+//   void Foo() : initializer = true {
+//        ^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_return_type.dart:3:8: Context: Previous declaration of 'Foo'.
+//   void Foo() {
+//        ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_return_type.dart:9:3: Error: Constructors can't have a return type.
+// Try removing the return type.
+//   void Foo.x() {
+//   ^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_return_type.dart:12:3: Error: Constructors can't have a return type.
+// Try removing the return type.
+//   void Foo.x() : initializer = true {
+//   ^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_return_type.dart:12:8: Error: 'Foo.x' is already declared in this scope.
+//   void Foo.x() : initializer = true {
+//        ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_return_type.dart:9:8: Context: Previous declaration of 'Foo.x'.
+//   void Foo.x() {
+//        ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_return_type.dart:6:16: Error: 'initializer' isn't an instance field of this class.
+//   void Foo() : initializer = true {
+//                ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_return_type.dart:12:18: Error: 'initializer' isn't an instance field of this class.
+//   void Foo.x() : initializer = true {
+//                  ^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  constructor •() → self::Foo*
+    : super core::Object::•() {}
+  constructor x() → self::Foo*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/constructor_recovery_set.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_set.dart.weak.modular.expect
new file mode 100644
index 0000000..b3eba22
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/constructor_recovery_set.dart.weak.modular.expect
@@ -0,0 +1,70 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_set.dart:3:7: Error: A class member can't have the same name as the enclosing class.
+// Try renaming the member.
+//   set Foo() {
+//       ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_set.dart:6:3: Error: Constructors can't be a setter.
+// Try removing 'set'.
+//   set Foo() : initializer = true {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_set.dart:9:3: Error: Constructors can't be a setter.
+// Try removing 'set'.
+//   set Foo.x() {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_set.dart:12:3: Error: Constructors can't be a setter.
+// Try removing 'set'.
+//   set Foo.x() : initializer = true {
+//   ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_set.dart:12:7: Error: 'Foo.x' is already declared in this scope.
+//   set Foo.x() : initializer = true {
+//       ^^^^^
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_set.dart:9:7: Context: Previous declaration of 'Foo.x'.
+//   set Foo.x() {
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_set.dart:3:10: Error: A setter should have exactly one formal parameter.
+//   set Foo() {
+//          ^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_set.dart:6:15: Error: 'initializer' isn't an instance field of this class.
+//   set Foo() : initializer = true {
+//               ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/constructor_recovery_set.dart:12:17: Error: 'initializer' isn't an instance field of this class.
+//   set Foo.x() : initializer = true {
+//                 ^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  constructor •() → self::Foo*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/error_recovery/constructor_recovery_set.dart:6:15: Error: 'initializer' isn't an instance field of this class.
+  set Foo() : initializer = true {
+              ^^^^^^^^^^^" {}
+  constructor x() → self::Foo*
+    : super core::Object::•() {}
+  set Foo(dynamic #synthetic) → void {
+    invalid-expression "pkg/front_end/testcases/general/error_recovery/constructor_recovery_set.dart:3:10: Error: A setter should have exactly one formal parameter.
+  set Foo() {
+         ^";
+    {}
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/empty_await_for.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/empty_await_for.dart.weak.modular.expect
new file mode 100644
index 0000000..ef2f7e9
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/empty_await_for.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/empty_await_for.dart:3:14: Error: Expected an identifier, but got ')'.
+// Try inserting an identifier before ')'.
+//   await for () {}
+//              ^
+//
+// pkg/front_end/testcases/general/error_recovery/empty_await_for.dart:3:14: Error: Expected 'in' before this.
+//   await for () {}
+//              ^
+//
+import self as self;
+
+static method main() → dynamic async {
+  await for (final dynamic #t1 in invalid-expression "pkg/front_end/testcases/general/error_recovery/empty_await_for.dart:3:14: Error: This couldn't be parsed.
+  await for () {}
+             ^") {
+    invalid-expression "pkg/front_end/testcases/general/error_recovery/empty_await_for.dart:3:14: Error: This couldn't be parsed.
+  await for () {}
+             ^";
+  }
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/empty_for.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/empty_for.dart.weak.modular.expect
new file mode 100644
index 0000000..35aa6ca
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/empty_for.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/empty_for.dart:3:8: Error: Expected an identifier, but got ')'.
+// Try inserting an identifier before ')'.
+//   for () {}
+//        ^
+//
+// pkg/front_end/testcases/general/error_recovery/empty_for.dart:3:7: Error: Expected ';' after this.
+//   for () {}
+//       ^
+//
+import self as self;
+
+static method main() → dynamic {
+  for (final invalid-type #t1 = invalid-expression "pkg/front_end/testcases/general/error_recovery/empty_for.dart:3:8: Error: This couldn't be parsed.
+  for () {}
+       ^"; invalid-expression "pkg/front_end/testcases/general/error_recovery/empty_for.dart:3:8: Error: This couldn't be parsed.
+  for () {}
+       ^"; ) {
+  }
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/for_in_with_colon.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/for_in_with_colon.dart.weak.modular.expect
new file mode 100644
index 0000000..9124332
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/for_in_with_colon.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/for_in_with_colon.dart:6:13: Error: For-in loops use 'in' rather than a colon.
+// Try replacing the colon with the keyword 'in'.
+//   for(int i : [1, 2, 3]) {
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  for (core::int* i in <core::int*>[1, 2, 3]) {
+    core::print(i);
+  }
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_22313.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_22313.dart.weak.modular.expect
new file mode 100644
index 0000000..4a09d61
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_22313.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_22313.dart:5:20: Error: Each class definition can have at most one extends clause.
+// Try choosing one superclass and define your class to implement (or mix in) the others.
+// class Foo extends A, B {
+//                    ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_22313.dart:9:11: Error: Expected 'extends' instead of this.
+// class Bar extend A, B {
+//           ^^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_22313.dart:9:19: Error: Each class definition can have at most one extends clause.
+// Try choosing one superclass and define your class to implement (or mix in) the others.
+// class Bar extend A, B {
+//                   ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_22313.dart:13:11: Error: Expected 'extends' instead of this.
+// class Baz on A, B {
+//           ^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_22313.dart:13:15: Error: Each class definition can have at most one extends clause.
+// Try choosing one superclass and define your class to implement (or mix in) the others.
+// class Baz on A, B {
+//               ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+}
+class Foo extends self::A {
+  constructor •() → self::Foo
+    : super self::A::•() {}
+}
+class Bar extends core::Object {
+  constructor •() → self::Bar
+    : super core::Object::•() {}
+}
+class Baz extends core::Object {
+  constructor •() → self::Baz
+    : super core::Object::•() {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_26810.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_26810.dart.weak.modular.expect
new file mode 100644
index 0000000..fa47aba
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_26810.dart.weak.modular.expect
@@ -0,0 +1,152 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_26810.dart:6:37: Error: Binary operator 'xor' is written as '^' instead of the written out word.
+// Try replacing 'xor' with '^'.
+//   int get a => runtimeType.hashCode xor null.hashCode;
+//                                     ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_26810.dart:11:41: Error: Binary operator 'xor' is written as '^' instead of the written out word.
+// Try replacing 'xor' with '^'.
+//   int get e => 1 + runtimeType.hashCode xor null.hashCode + 3;
+//                                         ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_26810.dart:16:28: Error: Binary operator 'xor' is written as '^' instead of the written out word.
+// Try replacing 'xor' with '^'.
+//   int i(int x, int y) => x xor y;
+//                            ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_26810.dart:23:32: Error: Binary operator 'xor' is written as '^' instead of the written out word.
+// Try replacing 'xor' with '^'.
+//   int o(int x, int y) => 1 + x xor y + 3;
+//                                ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_26810.dart:36:31: Error: Binary operator 'xor' is written as '^' instead of the written out word.
+// Try replacing 'xor' with '^'.
+//   Key(int x, int y) : foo = x xor y, bar = x xor y {
+//                               ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_26810.dart:36:46: Error: Binary operator 'xor' is written as '^' instead of the written out word.
+// Try replacing 'xor' with '^'.
+//   Key(int x, int y) : foo = x xor y, bar = x xor y {
+//                                              ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_26810.dart:8:43: Error: Binary operator 'xor' is written as '^' instead of the written out word.
+// Try replacing 'xor' with '^'.
+//   int get c { return runtimeType.hashCode xor null.hashCode; }
+//                                           ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_26810.dart:13:47: Error: Binary operator 'xor' is written as '^' instead of the written out word.
+// Try replacing 'xor' with '^'.
+//   int get g { return 1 + runtimeType.hashCode xor null.hashCode + 3; }
+//                                               ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_26810.dart:18:34: Error: Binary operator 'xor' is written as '^' instead of the written out word.
+// Try replacing 'xor' with '^'.
+//   int k(int x, int y) { return x xor y; }
+//                                  ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_26810.dart:20:36: Error: Binary operator 'xor' is written as '^' instead of the written out word.
+// Try replacing 'xor' with '^'.
+//   int m(int x, int y) { int z =  x xor y; return z; }
+//                                    ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_26810.dart:25:38: Error: Binary operator 'xor' is written as '^' instead of the written out word.
+// Try replacing 'xor' with '^'.
+//   int q(int x, int y) { return 1 + x xor y + 3; }
+//                                      ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_26810.dart:29:9: Error: Binary operator 'xor' is written as '^' instead of the written out word.
+// Try replacing 'xor' with '^'.
+//     s(x xor y, x xor y);
+//         ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_26810.dart:29:18: Error: Binary operator 'xor' is written as '^' instead of the written out word.
+// Try replacing 'xor' with '^'.
+//     s(x xor y, x xor y);
+//                  ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_26810.dart:37:22: Error: Binary operator 'xor' is written as '^' instead of the written out word.
+// Try replacing 'xor' with '^'.
+//     print("hello ${x xor y}");
+//                      ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Key extends core::Object {
+  field core::int* foo;
+  field core::int* bar;
+  constructor •(core::int* x, core::int* y) → self::Key*
+    : self::Key::foo = x.{core::int::^}(y){(core::int*) →* core::int*}, self::Key::bar = x.{core::int::^}(y){(core::int*) →* core::int*}, super core::Object::•() {
+    core::print("hello ${x.{core::int::^}(y){(core::int*) →* core::int*}}");
+  }
+  constructor NotDuplicate(core::int* x, core::int* y) → self::Key*
+    : self::Key::foo = x.{core::int::^}(y){(core::int*) →* core::int*}, self::Key::bar = x.{core::int::^}(y){(core::int*) →* core::int*}, super core::Object::•() {
+    core::print("hello ${x.{core::int::^}(y){(core::int*) →* core::int*}}");
+  }
+  get a() → core::int*
+    return this.{self::Key::runtimeType}{core::Type*}.{core::Type::hashCode}{core::int*}.{core::int::^}(null.{core::Object::hashCode}{core::int*}){(core::int*) →* core::int*};
+  get b() → core::int*
+    return this.{self::Key::runtimeType}{core::Type*}.{core::Type::hashCode}{core::int*}.{core::int::^}(null.{core::Object::hashCode}{core::int*}){(core::int*) →* core::int*};
+  get c() → core::int* {
+    return this.{self::Key::runtimeType}{core::Type*}.{core::Type::hashCode}{core::int*}.{core::int::^}(null.{core::Object::hashCode}{core::int*}){(core::int*) →* core::int*};
+  }
+  get d() → core::int* {
+    return this.{self::Key::runtimeType}{core::Type*}.{core::Type::hashCode}{core::int*}.{core::int::^}(null.{core::Object::hashCode}{core::int*}){(core::int*) →* core::int*};
+  }
+  get e() → core::int*
+    return 1.{core::num::+}(this.{self::Key::runtimeType}{core::Type*}.{core::Type::hashCode}{core::int*}){(core::num*) →* core::int*}.{core::int::^}(null.{core::Object::hashCode}{core::int*}.{core::num::+}(3){(core::num*) →* core::int*}){(core::int*) →* core::int*};
+  get f() → core::int*
+    return 1.{core::num::+}(this.{self::Key::runtimeType}{core::Type*}.{core::Type::hashCode}{core::int*}){(core::num*) →* core::int*}.{core::int::^}(null.{core::Object::hashCode}{core::int*}.{core::num::+}(3){(core::num*) →* core::int*}){(core::int*) →* core::int*};
+  get g() → core::int* {
+    return 1.{core::num::+}(this.{self::Key::runtimeType}{core::Type*}.{core::Type::hashCode}{core::int*}){(core::num*) →* core::int*}.{core::int::^}(null.{core::Object::hashCode}{core::int*}.{core::num::+}(3){(core::num*) →* core::int*}){(core::int*) →* core::int*};
+  }
+  get h() → core::int* {
+    return 1.{core::num::+}(this.{self::Key::runtimeType}{core::Type*}.{core::Type::hashCode}{core::int*}){(core::num*) →* core::int*}.{core::int::^}(null.{core::Object::hashCode}{core::int*}.{core::num::+}(3){(core::num*) →* core::int*}){(core::int*) →* core::int*};
+  }
+  method i(core::int* x, core::int* y) → core::int*
+    return x.{core::int::^}(y){(core::int*) →* core::int*};
+  method j(core::int* x, core::int* y) → core::int*
+    return x.{core::int::^}(y){(core::int*) →* core::int*};
+  method k(core::int* x, core::int* y) → core::int* {
+    return x.{core::int::^}(y){(core::int*) →* core::int*};
+  }
+  method l(core::int* x, core::int* y) → core::int* {
+    return x.{core::int::^}(y){(core::int*) →* core::int*};
+  }
+  method m(core::int* x, core::int* y) → core::int* {
+    core::int* z = x.{core::int::^}(y){(core::int*) →* core::int*};
+    return z;
+  }
+  method n(core::int* x, core::int* y) → core::int* {
+    core::int* z = x.{core::int::^}(y){(core::int*) →* core::int*};
+    return z;
+  }
+  method o(core::int* x, core::int* y) → core::int*
+    return 1.{core::num::+}(x){(core::num*) →* core::int*}.{core::int::^}(y.{core::num::+}(3){(core::num*) →* core::int*}){(core::int*) →* core::int*};
+  method p(core::int* x, core::int* y) → core::int*
+    return 1.{core::num::+}(x){(core::num*) →* core::int*}.{core::int::^}(y.{core::num::+}(3){(core::num*) →* core::int*}){(core::int*) →* core::int*};
+  method q(core::int* x, core::int* y) → core::int* {
+    return 1.{core::num::+}(x){(core::num*) →* core::int*}.{core::int::^}(y.{core::num::+}(3){(core::num*) →* core::int*}){(core::int*) →* core::int*};
+  }
+  method r(core::int* x, core::int* y) → core::int* {
+    return 1.{core::num::+}(x){(core::num*) →* core::int*}.{core::int::^}(y.{core::num::+}(3){(core::num*) →* core::int*}){(core::int*) →* core::int*};
+  }
+  method s(core::int* x, core::int* y) → dynamic {
+    this.{self::Key::s}(x.{core::int::^}(y){(core::int*) →* core::int*}, x.{core::int::^}(y){(core::int*) →* core::int*}){(core::int*, core::int*) →* dynamic};
+    this.{self::Key::s}(x.{core::int::^}(y){(core::int*) →* core::int*}, x.{core::int::^}(y){(core::int*) →* core::int*}){(core::int*, core::int*) →* dynamic};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_38415.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_38415.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..75defa5
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_38415.crash_dart.weak.modular.expect
@@ -0,0 +1,51 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_38415.crash_dart:1:12: Error: Can't find ')' to match '('.
+// f() { m(T<R(<Z
+//            ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_38415.crash_dart:1:10: Error: Can't find '>' to match '<'.
+// f() { m(T<R(<Z
+//          ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_38415.crash_dart:1:8: Error: Can't find ')' to match '('.
+// f() { m(T<R(<Z
+//        ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_38415.crash_dart:1:5: Error: Can't find '}' to match '{'.
+// f() { m(T<R(<Z
+//     ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_38415.crash_dart:1:14: Error: 'Z' isn't a type.
+// f() { m(T<R(<Z
+//              ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_38415.crash_dart:1:15: Error: Expected '[' before this.
+// f() { m(T<R(<Z
+//               ^...
+//
+// pkg/front_end/testcases/general/error_recovery/issue_38415.crash_dart:1:11: Error: Method not found: 'R'.
+// f() { m(T<R(<Z
+//           ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_38415.crash_dart:1:9: Error: Undefined name 'T'.
+// f() { m(T<R(<Z
+//         ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_38415.crash_dart:1:7: Error: Method not found: 'm'.
+// f() { m(T<R(<Z
+//       ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_38415.crash_dart:1:15: Error: Expected ';' after this.
+// f() { m(T<R(<Z
+//               ^...
+//
+import self as self;
+
+static method f() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/error_recovery/issue_38415.crash_dart:1:7: Error: Method not found: 'm'.
+f() { m(T<R(<Z
+      ^";
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_39024.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_39024.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..679fe85
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_39024.crash_dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39024.crash_dart:1:6: Error: Can't find ')' to match '('.
+// n<S e(
+//      ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39024.crash_dart:1:2: Error: Can't find '>' to match '<'.
+// n<S e(
+//  ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39024.crash_dart:1:3: Error: Expected '>' after this.
+// n<S e(
+//   ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39024.crash_dart:1:7: Error: Expected an identifier, but got ''.
+// Try inserting an identifier before ''.
+// n<S e(
+//       ^...
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39024.crash_dart:1:7: Error: A function declaration needs an explicit list of parameters.
+// Try adding a parameter list to the function declaration.
+// n<S e(
+//       ^...
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39024.crash_dart:1:7: Error: Expected '{' before this.
+// n<S e(
+//       ^...
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39024.crash_dart:1:3: Error: Type 'S' not found.
+// n<S e(
+//   ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39024.crash_dart:1:1: Error: Type 'n' not found.
+// n<S e(
+// ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39024.crash_dart:1:1: Error: Expected 0 type arguments.
+// n<S e(
+// ^
+//
+import self as self;
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_39026.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_39026.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..ac2beca
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_39026.crash_dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39026.crash_dart:2:8: Error: Operator declarations must be preceded by the keyword 'operator'.
+// Try adding the keyword 'operator'.
+//     co <{
+//        ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39026.crash_dart:2:8: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//     co <{
+//        ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39026.crash_dart:2:8: Error: Operator '<' should have exactly one parameter.
+//     co <{
+//        ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39026.crash_dart:2:5: Error: Type 'co' not found.
+//     co <{
+//     ^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  operator <() → invalid-type {}
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_39026_prime.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_39026_prime.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..65bece2
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_39026_prime.crash_dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39026_prime.crash_dart:2:17: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//     co operator <{
+//                 ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39026_prime.crash_dart:2:17: Error: Operator '<' should have exactly one parameter.
+//     co operator <{
+//                 ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39026_prime.crash_dart:2:5: Error: Type 'co' not found.
+//     co operator <{
+//     ^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  operator <() → invalid-type {}
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_39033.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_39033.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..0292288
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_39033.crash_dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39033.crash_dart:1:11: Error: Expected '>' after this.
+// typedef F<Glib.=
+//           ^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39033.crash_dart:1:17: Error: Expected a type, but got ''.
+// typedef F<Glib.=
+//                 ^...
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39033.crash_dart:1:16: Error: Expected ';' after this.
+// typedef F<Glib.=
+//                ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39033.crash_dart:1:16: Error: Can't create typedef from non-type.
+// typedef F<Glib.=
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F<unrelated Glib extends core::Object? = dynamic> = invalid-type;
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_39033b.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_39033b.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..cd13068
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_39033b.crash_dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39033b.crash_dart:2:11: Error: Expected '>' after this.
+// typedef F<Glib.=
+//           ^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39033b.crash_dart:2:17: Error: Expected a type, but got ''.
+// typedef F<Glib.=
+//                 ^...
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39033b.crash_dart:2:16: Error: Expected ';' after this.
+// typedef F<Glib.=
+//                ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39033b.crash_dart:2:16: Error: Can't create typedef from non-type.
+// typedef F<Glib.=
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F<unrelated Glib extends core::Object? = dynamic> = invalid-type;
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_39058.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_39058.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..d532f41
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_39058.crash_dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39058.crash_dart:1:5: Error: Can't find ')' to match '('.
+// {<[](
+//     ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39058.crash_dart:1:2: Error: Can't find '>' to match '<'.
+// {<[](
+//  ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39058.crash_dart:1:1: Error: Can't find '}' to match '{'.
+// {<[](
+// ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39058.crash_dart:1:1: Error: Expected a declaration, but got '{'.
+// {<[](
+// ^
+//
+import self as self;
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_39058_prime.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_39058_prime.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..ae54add
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_39058_prime.crash_dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39058_prime.crash_dart:1:1: Error: Expected a declaration, but got '{'.
+// {<[]()>}
+// ^
+//
+import self as self;
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_39060.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_39060.dart.weak.modular.expect
new file mode 100644
index 0000000..a49ea7c
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_39060.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39060.dart:3:4: Error: 's' isn't a type.
+//   {s A<}>
+//    ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39060.dart:3:6: Error: Expected ';' after this.
+//   {s A<}>
+//      ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39060.dart:3:8: Error: Expected a type, but got '}'.
+//   {s A<}>
+//        ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39060.dart:3:8: Error: This couldn't be parsed.
+//   {s A<}>
+//        ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39060.dart:4:1: Error: Expected '[' before this.
+// }
+// ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39060.dart:4:1: Error: Expected ';' after this.
+// }
+// ^
+//
+import self as self;
+
+static method main() → dynamic {
+  {
+    invalid-type A;
+    <invalid-type>[];
+  }
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..e1e7c23
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart:1:1: Error: Expected a declaration, but got '('.
+// () async => a b < c $? >
+// ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart:1:2: Error: Expected a declaration, but got ')'.
+// () async => a b < c $? >
+//  ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart:1:4: Error: A function declaration needs an explicit list of parameters.
+// Try adding a parameter list to the function declaration.
+// () async => a b < c $? >
+//    ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart:1:19: Error: Expected '>' after this.
+// () async => a b < c $? >
+//                   ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart:1:25: Error: Expected an identifier, but got ''.
+// Try inserting an identifier before ''.
+// () async => a b < c $? >
+//                         ^...
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart:1:24: Error: Expected ';' after this.
+// () async => a b < c $? >
+//                        ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart:1:19: Error: Type 'c' not found.
+// () async => a b < c $? >
+//                   ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart:1:15: Error: Type 'b' not found.
+// () async => a b < c $? >
+//               ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart:1:15: Error: Expected 0 type arguments.
+// () async => a b < c $? >
+//               ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart:1:13: Error: Expected ';' after this.
+// () async => a b < c $? >
+//             ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart:1:13: Error: Undefined name 'a'.
+// () async => a b < c $? >
+//             ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart:1:15: Error: Unexpected token 'b'.
+// () async => a b < c $? >
+//               ^
+//
+import self as self;
+
+static method async() → dynamic
+  return invalid-expression "pkg/front_end/testcases/general/error_recovery/issue_39202.crash_dart:1:13: Error: Undefined name 'a'.
+() async => a b < c \$? >
+            ^";
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_39230.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_39230.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..34c35fb
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_39230.crash_dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39230.crash_dart:3:5: Error: Expected '{' before this.
+//     /
+//     ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39230.crash_dart:3:5: Error: Operator declarations must be preceded by the keyword 'operator'.
+// Try adding the keyword 'operator'.
+//     /
+//     ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39230.crash_dart:3:5: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//     /
+//     ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39230.crash_dart:3:5: Error: The name of a constructor must match the name of the enclosing class.
+//     /
+//     ^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39230.crash_dart:3:5: Error: Operator '/' should have exactly one parameter.
+//     /
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  constructor •() → self::C
+    : super core::Object::•() {}
+  constructor /() → self::C
+    : super core::Object::•()
+    ;
+}
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_39958_01.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_39958_01.dart.weak.modular.expect
new file mode 100644
index 0000000..0b3c58e
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_39958_01.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39958_01.dart:2:5: Error: Type 'void' can't have type arguments.
+// Try removing the type arguments.
+// void<int> f() {}
+//     ^
+//
+import self as self;
+
+static method f() → void {}
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_39958_02.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_39958_02.dart.weak.modular.expect
new file mode 100644
index 0000000..f4c6611
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_39958_02.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39958_02.dart:2:1: Error: Expected 0 type arguments.
+// dynamic<int> f() {}
+// ^
+//
+import self as self;
+
+static method f() → invalid-type {}
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_39958_03.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_39958_03.dart.weak.modular.expect
new file mode 100644
index 0000000..46d364b
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_39958_03.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39958_03.dart:2:1: Error: Expected 0 type arguments.
+// int<int> f() {}
+// ^
+//
+import self as self;
+
+static method f() → invalid-type {}
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_39958_04.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_39958_04.dart.weak.modular.expect
new file mode 100644
index 0000000..b829820
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_39958_04.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39958_04.dart:2:1: Error: Type 'Foo' not found.
+// Foo<int> f() {}
+// ^^^
+//
+// pkg/front_end/testcases/general/error_recovery/issue_39958_04.dart:2:1: Error: Expected 0 type arguments.
+// Foo<int> f() {}
+// ^
+//
+import self as self;
+
+static method f() → invalid-type {}
diff --git a/pkg/front_end/testcases/general/error_recovery/issue_43090.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/issue_43090.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..c79c850
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/issue_43090.crash_dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/issue_43090.crash_dart:1:12: Error: Expected an identifier, but got '='.
+// Try inserting an identifier before '='.
+// typedef A< = void Function();
+//            ^
+//
+import self as self;
+
+typedef A = () → void;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/error_recovery/yield_not_in_generator.dart.weak.modular.expect b/pkg/front_end/testcases/general/error_recovery/yield_not_in_generator.dart.weak.modular.expect
new file mode 100644
index 0000000..c923736
--- /dev/null
+++ b/pkg/front_end/testcases/general/error_recovery/yield_not_in_generator.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/error_recovery/yield_not_in_generator.dart:4:3: Error: 'yield' can only be used in 'sync*' or 'async*' methods.
+//   yield f();
+//   ^^^^^
+//
+// pkg/front_end/testcases/general/error_recovery/yield_not_in_generator.dart:3:11: Error: A non-null value must be returned since the return type 'List<int>' doesn't allow null.
+//  - 'List' is from 'dart:core'.
+// List<int> g() {
+//           ^
+//
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+static method f() → asy::Future<core::int>
+  return asy::Future::value<core::int>(7);
+static method g() → core::List<core::int> {
+  invalid-expression "pkg/front_end/testcases/general/error_recovery/yield_not_in_generator.dart:4:3: Error: 'yield' can only be used in 'sync*' or 'async*' methods.
+  yield f();
+  ^";
+  return invalid-expression "pkg/front_end/testcases/general/error_recovery/yield_not_in_generator.dart:3:11: Error: A non-null value must be returned since the return type 'List<int>' doesn't allow null.
+ - 'List' is from 'dart:core'.
+List<int> g() {
+          ^" in null;
+}
diff --git a/pkg/front_end/testcases/general/escape.dart.weak.modular.expect b/pkg/front_end/testcases/general/escape.dart.weak.modular.expect
new file mode 100644
index 0000000..e9c05d7
--- /dev/null
+++ b/pkg/front_end/testcases/general/escape.dart.weak.modular.expect
@@ -0,0 +1,89 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field dynamic field = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  field dynamic field = null;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  operator ==(dynamic x) → core::bool*
+    return false;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class X extends core::Object implements self::A, self::B {
+  field dynamic field = null;
+  synthetic constructor •() → self::X*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method useAsA(self::A* object) → void {
+  dynamic _ = object.{self::A::field}{dynamic};
+}
+static method useAsB(self::B* object) → void {
+  dynamic _ = object.{self::B::field}{dynamic};
+  self::escape(object);
+}
+static method escape(dynamic x) → void {
+  x == null ?{dynamic} x = "" : null;
+  x == null ?{dynamic} x = 45 : null;
+  if(!(x is core::int*) && !(x is core::String*)) {
+    x{dynamic}.field = 45;
+  }
+}
+static method main() → dynamic {
+  self::X* object = new self::X::•();
+  self::useAsA(new self::A::•());
+  self::useAsA(object);
+  self::useAsB(new self::B::•());
+  self::useAsB(object);
+}
diff --git a/pkg/front_end/testcases/general/experiment_release_version/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/experiment_release_version/main.dart.weak.modular.expect
new file mode 100644
index 0000000..b77b7a9
--- /dev/null
+++ b/pkg/front_end/testcases/general/experiment_release_version/main.dart.weak.modular.expect
@@ -0,0 +1,120 @@
+//
+// Problems outside component:
+//
+// pkg/front_end/testcases/general/experiment_release_version/not_allowed_package/lib/unversioned_lib.dart:5:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.10 or higher.
+// int? versionedUnallowedPackage; // error
+//    ^
+// pkg/front_end/testcases/general/experiment_release_version/not_allowed_package/lib/unversioned_lib.dart:4:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.9
+// ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/experiment_release_version/not_allowed_package/lib/versioned_2_8_lib.dart:7:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.10 or higher.
+// int? versioned_2_8_AllowedPackage; // error
+//    ^
+// pkg/front_end/testcases/general/experiment_release_version/not_allowed_package/lib/versioned_2_8_lib.dart:4:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.9
+// ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/experiment_release_version/not_allowed_package/lib/versioned_2_9_lib.dart:7:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.10 or higher.
+// int? versioned_2_9_AllowedPackage; // error
+//    ^
+// pkg/front_end/testcases/general/experiment_release_version/not_allowed_package/lib/versioned_2_9_lib.dart:4:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.9
+// ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/experiment_release_version/not_allowed_package/lib/versioned_2_10_lib.dart:7:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.10 or higher.
+// int? versionedAllowedPackage; // error
+//    ^
+// pkg/front_end/testcases/general/experiment_release_version/not_allowed_package/lib/versioned_2_10_lib.dart:4:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.9
+// ^^^^^^^^^^^^
+//
+library;
+import self as self;
+
+import "package:allowed_package/unversioned_lib.dart";
+import "package:allowed_package/versioned_2_8_lib.dart";
+import "package:allowed_package/versioned_2_9_lib.dart";
+import "package:allowed_package/versioned_2_10_lib.dart";
+import "package:not_allowed_package/unversioned_lib.dart";
+import "package:not_allowed_package/versioned_2_8_lib.dart";
+import "package:not_allowed_package/versioned_2_9_lib.dart";
+import "package:not_allowed_package/versioned_2_10_lib.dart";
+import "org-dartlang-testcase:///unversioned_lib.dart";
+import "org-dartlang-testcase:///versioned_2_8_lib.dart";
+import "org-dartlang-testcase:///versioned_2_9_lib.dart";
+import "org-dartlang-testcase:///versioned_2_10_lib.dart";
+
+static method main() → dynamic {}
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/experiment_release_version/unversioned_lib.dart:5:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.10 or higher.
+// int? unversionedLibrary; // error
+//    ^
+// pkg/front_end/testcases/general/experiment_release_version/unversioned_lib.dart:4:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.9
+// ^^^^^^^^^^^^
+//
+import self as self2;
+import "dart:core" as core;
+
+static field core::int? unversionedLibrary;
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/experiment_release_version/versioned_2_8_lib.dart:7:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.10 or higher.
+// int? versioned_2_8_Library; // error
+//    ^
+// pkg/front_end/testcases/general/experiment_release_version/versioned_2_8_lib.dart:4:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.9
+// ^^^^^^^^^^^^
+//
+import self as self3;
+import "dart:core" as core;
+
+static field core::int? versioned_2_8_Library;
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/experiment_release_version/versioned_2_9_lib.dart:7:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.10 or higher.
+// int? versioned_2_9_Library; // error
+//    ^
+// pkg/front_end/testcases/general/experiment_release_version/versioned_2_9_lib.dart:4:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.9
+// ^^^^^^^^^^^^
+//
+import self as self4;
+import "dart:core" as core;
+
+static field core::int? versioned_2_9_Library;
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/experiment_release_version/versioned_2_10_lib.dart:7:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.10 or higher.
+// int? versioned_2_10_Library; // error
+//    ^
+// pkg/front_end/testcases/general/experiment_release_version/versioned_2_10_lib.dart:4:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.9
+// ^^^^^^^^^^^^
+//
+import self as self5;
+import "dart:core" as core;
+
+static field core::int? versioned_2_10_Library;
diff --git a/pkg/front_end/testcases/general/export_main.dart.weak.modular.expect b/pkg/front_end/testcases/general/export_main.dart.weak.modular.expect
new file mode 100644
index 0000000..94479f0
--- /dev/null
+++ b/pkg/front_end/testcases/general/export_main.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library;
+import self as self;
+import "hello.dart" as hel;
+additionalExports = (hel::main)
+
+export "org-dartlang-testcase:///hello.dart" show main;
+
+
+library;
+import self as hel;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::print("Hello, World!");
+}
diff --git a/pkg/front_end/testcases/general/export_test.dart.weak.modular.expect b/pkg/front_end/testcases/general/export_test.dart.weak.modular.expect
new file mode 100644
index 0000000..497ce03
--- /dev/null
+++ b/pkg/front_end/testcases/general/export_test.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library;
+import self as self;
+import "dart:core" as core;
+additionalExports = (core::print)
+
+import "dart:developer" show UserTag;
+export "dart:core" show print;
+
+static method main() → dynamic {
+  core::print(#C1);
+}
+
+constants  {
+  #C1 = TypeLiteralConstant(dev::UserTag*)
+}
diff --git a/pkg/front_end/testcases/general/expressions.dart.weak.modular.expect b/pkg/front_end/testcases/general/expressions.dart.weak.modular.expect
new file mode 100644
index 0000000..20f5b17
--- /dev/null
+++ b/pkg/front_end/testcases/general/expressions.dart.weak.modular.expect
@@ -0,0 +1,101 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/expressions.dart:74:16: Error: Method not found: 'int.toString'.
+//     print(int?.toString());
+//                ^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method foo({dynamic fisk = #C1}) → dynamic {
+  core::print(fisk);
+}
+static method caller(dynamic f) → dynamic {
+  f{dynamic}.call();
+}
+static method main() → dynamic {
+  core::int* i = 0;
+  core::print(i =={core::num::==}{(core::Object*) →* core::bool*} 1 ?{core::String*} "bad" : "good");
+  core::print("${i}");
+  core::print("'${i}'");
+  core::print(" '${i}' ");
+  core::print(" '${i}' '${i}'");
+  core::print(" '${i}' '${i}'");
+  core::print("foobar");
+  core::print(" '${i}' '${i}' '${i}' '${i}'");
+  try {
+    throw "fisk";
+  }
+  on core::String* catch(final core::String* e, final core::StackTrace* s) {
+    core::print(e);
+    if(!(s == null))
+      core::print(s);
+  }
+  for (; false; ) {
+  }
+  core::List<core::String*>* list = <core::String*>["Hello, World!"];
+  core::print(list.{core::List::[]}(i){(core::int*) →* core::String*});
+  list.{core::List::[]=}(i, "Hello, Brave New World!"){(core::int*, core::String*) →* void};
+  core::print(list.{core::List::[]}(i){(core::int*) →* core::String*});
+  i = 87;
+  core::print(i.{core::int::unary-}(){() →* core::int*});
+  core::print(i.{core::int::~}(){() →* core::int*});
+  core::print(!(i =={core::num::==}{(core::Object*) →* core::bool*} 42));
+  core::print(i = i.{core::num::-}(1){(core::num*) →* core::int*});
+  core::print(i = i.{core::num::+}(1){(core::num*) →* core::int*});
+  core::print(let final core::int* #t1 = i in let final core::int* #t2 = i = #t1.{core::num::-}(1){(core::num*) →* core::int*} in #t1);
+  core::print(let final core::int* #t3 = i in let final core::int* #t4 = i = #t3.{core::num::+}(1){(core::num*) →* core::int*} in #t3);
+  core::print(new core::Object::•());
+  core::print(#C2);
+  core::print(core::List::filled<core::String*>(2, null).{core::Object::runtimeType}{core::Type*});
+  self::foo(fisk: "Blorp gulp");
+  function f() → Null {
+    core::print("f was called");
+  }
+  self::caller(f);
+  self::caller(() → Null {
+    core::print("<anon> was called");
+  });
+  function g([dynamic message = #C1]) → Null {
+    core::print(message);
+  }
+  g("Hello, World"){([dynamic]) →* Null};
+  self::caller(([dynamic x = #C1]) → Null {
+    core::print("<anon> was called with ${x}");
+  });
+  function h({dynamic message = #C1}) → Null {
+    core::print(message);
+  }
+  h(message: "Hello, World"){({message: dynamic}) →* Null};
+  self::caller(({dynamic x = #C1}) → Null {
+    core::print("<anon> was called with ${x}");
+  });
+  core::print(#C3.{core::Type::toString}(){() →* core::String*});
+  core::print(#C3);
+  core::print(let final core::Type* #t5 = #C3 in block {
+    #t5.{core::Type::toString}(){() →* core::String*};
+  } =>#t5);
+  try {
+    core::print(invalid-expression "pkg/front_end/testcases/general/expressions.dart:74:16: Error: Method not found: 'int.toString'.
+    print(int?.toString());
+               ^^^^^^^^");
+    throw "Shouldn't work";
+  }
+  on core::NoSuchMethodError* catch(final core::NoSuchMethodError* e) {
+    core::print("As expected: ${e}");
+  }
+  core::print(core::int::parse("42"));
+}
+
+constants  {
+  #C1 = null
+  #C2 = core::Object {}
+  #C3 = TypeLiteralConstant(core::int*)
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///expressions.dart:
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/extend_with_type_variable.dart.weak.modular.expect b/pkg/front_end/testcases/general/extend_with_type_variable.dart.weak.modular.expect
new file mode 100644
index 0000000..8ead278
--- /dev/null
+++ b/pkg/front_end/testcases/general/extend_with_type_variable.dart.weak.modular.expect
@@ -0,0 +1,77 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/extend_with_type_variable.dart:13:7: Error: The type 'M' can't be mixed in.
+// class Class2<T, M extends Mixin<T>> extends SuperClass with M {}
+//       ^
+//
+// pkg/front_end/testcases/general/extend_with_type_variable.dart:11:7: Error: The type variable 'S' can't be used as supertype.
+// class Class1<T, S extends SuperClass> extends S with Mixin<T> {}
+//       ^
+//
+// pkg/front_end/testcases/general/extend_with_type_variable.dart:13:7: Error: The type variable 'M' can't be used as supertype.
+// class Class2<T, M extends Mixin<T>> extends SuperClass with M {}
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class SuperClass extends core::Object {
+  synthetic constructor •() → self::SuperClass*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Mixin<T extends core::Object* = dynamic> extends core::Object /*isMixinDeclaration*/  {
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Class1&S&Mixin<T extends core::Object* = dynamic, S extends self::SuperClass*> = core::Object with self::Mixin<self::_Class1&S&Mixin::T*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class1&S&Mixin<self::_Class1&S&Mixin::T*, self::_Class1&S&Mixin::S*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class1<T extends core::Object* = dynamic, S extends self::SuperClass*> extends self::_Class1&S&Mixin<self::Class1::T*, self::Class1::S*> {
+  synthetic constructor •() → self::Class1<self::Class1::T*, self::Class1::S*>*
+    : super self::_Class1&S&Mixin::•()
+    ;
+}
+abstract class _Class2&SuperClass&M<T extends core::Object* = dynamic, M extends self::Mixin<self::_Class2&SuperClass&M::T*>* = self::Mixin<dynamic>*> extends self::SuperClass /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class2&SuperClass&M<self::_Class2&SuperClass&M::T*, self::_Class2&SuperClass&M::M*>*
+    : super self::SuperClass::•()
+    ;
+}
+class Class2<T extends core::Object* = dynamic, M extends self::Mixin<self::Class2::T*>* = self::Mixin<dynamic>*> extends self::_Class2&SuperClass&M<self::Class2::T*, self::Class2::M*> {
+  synthetic constructor •() → self::Class2<self::Class2::T*, self::Class2::M*>*
+    : super self::_Class2&SuperClass&M::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/extension_annotation.dart.weak.modular.expect b/pkg/front_end/testcases/general/extension_annotation.dart.weak.modular.expect
new file mode 100644
index 0000000..d44af16
--- /dev/null
+++ b/pkg/front_end/testcases/general/extension_annotation.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+@#C1
+extension Extension on core::int {
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::A {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///extension_annotation.dart:
+- A. (from org-dartlang-testcase:///extension_annotation.dart:6:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/extension_type_when_experiment_not_enabled.dart.weak.modular.expect b/pkg/front_end/testcases/general/extension_type_when_experiment_not_enabled.dart.weak.modular.expect
new file mode 100644
index 0000000..dfe0844
--- /dev/null
+++ b/pkg/front_end/testcases/general/extension_type_when_experiment_not_enabled.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/extension_type_when_experiment_not_enabled.dart:11:6: Error: This requires the 'extension-types' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// test(E e) {} // Error.
+//      ^
+//
+// pkg/front_end/testcases/general/extension_type_when_experiment_not_enabled.dart:11:6: Error: 'E' isn't a type.
+// test(E e) {} // Error.
+//      ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+extension E on self::A {
+}
+static method test(invalid-type e) → dynamic {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/extension_types_feature_not_enabled.dart.weak.modular.expect b/pkg/front_end/testcases/general/extension_types_feature_not_enabled.dart.weak.modular.expect
new file mode 100644
index 0000000..0c596cb
--- /dev/null
+++ b/pkg/front_end/testcases/general/extension_types_feature_not_enabled.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/extension_types_feature_not_enabled.dart:9:11: Error: This requires the 'extension-types' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// extension type E on A {} // Error because of 'type'.
+//           ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+extension type E on self::A {
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/external.dart.weak.modular.expect b/pkg/front_end/testcases/general/external.dart.weak.modular.expect
new file mode 100644
index 0000000..5e9b241
--- /dev/null
+++ b/pkg/front_end/testcases/general/external.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:isolate" as iso;
+import "dart:async" as asy;
+
+import "dart:isolate";
+
+static field dynamic subscription;
+static method onData(dynamic x) → void {
+  core::print(x);
+  self::subscription{dynamic}.cancel();
+}
+static method main() → dynamic {
+  core::String* string = core::String::fromCharCode(65);
+  iso::ReceivePort* port = iso::ReceivePort::•();
+  self::subscription = port.{iso::ReceivePort::listen}(#C1){((dynamic) →* void, {cancelOnError: core::bool*, onDone: () →* void, onError: core::Function*}) →* asy::StreamSubscription<dynamic>*};
+  port.{iso::ReceivePort::sendPort}{iso::SendPort*}.{iso::SendPort::send}(string){(core::Object*) →* void};
+}
+
+constants  {
+  #C1 = static-tearoff self::onData
+}
diff --git a/pkg/front_end/testcases/general/external_import.dart.weak.modular.expect b/pkg/front_end/testcases/general/external_import.dart.weak.modular.expect
new file mode 100644
index 0000000..0d7662f
--- /dev/null
+++ b/pkg/front_end/testcases/general/external_import.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+@#C2
+@#C4
+@#C6
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/external_import.dart:7:1: Error: Dart native extensions are no longer supported.
+// Migrate to using FFI instead (https://dart.dev/guides/libraries/c-interop)
+// import 'dart-ext:here';
+// ^
+//
+// pkg/front_end/testcases/general/external_import.dart:8:1: Error: Dart native extensions are no longer supported.
+// Migrate to using FFI instead (https://dart.dev/guides/libraries/c-interop)
+// import 'dart-ext:foo/../there';
+// ^
+//
+// pkg/front_end/testcases/general/external_import.dart:9:1: Error: Dart native extensions are no longer supported.
+// Migrate to using FFI instead (https://dart.dev/guides/libraries/c-interop)
+// import 'dart-ext:/usr/local/somewhere';
+// ^
+//
+import self as self;
+import "dart:_internal" as _in;
+
+static method main() → dynamic {}
+
+constants  {
+  #C1 = "dart-ext:here"
+  #C2 = _in::ExternalName {name:#C1}
+  #C3 = "dart-ext:foo/../there"
+  #C4 = _in::ExternalName {name:#C3}
+  #C5 = "dart-ext:/usr/local/somewhere"
+  #C6 = _in::ExternalName {name:#C5}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///external_import.dart:
+- ExternalName. (from org-dartlang-sdk:///sdk/lib/internal/internal.dart:92:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/external_method.dart.weak.modular.expect b/pkg/front_end/testcases/general/external_method.dart.weak.modular.expect
new file mode 100644
index 0000000..323ca66
--- /dev/null
+++ b/pkg/front_end/testcases/general/external_method.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  external method externalMethod() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+external static method externalMethod() → void;
+static method main() → void {}
diff --git a/pkg/front_end/testcases/general/factory_patch/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/factory_patch/main.dart.weak.modular.expect
new file mode 100644
index 0000000..0cdd47c
--- /dev/null
+++ b/pkg/front_end/testcases/general/factory_patch/main.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:test" as test;
+
+import "dart:test";
+
+static method main() → dynamic {
+  test::Class::fact();
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/factory_patch/patch_lib.dart:22:52: Error: Can't have a default value here because any default values of 'Class._internal' would be used instead.
+// Try removing the default value.
+//   const factory Class.redirect({bool defaultValue: true}) = Class._internal;
+//                                                    ^
+//
+import self as test;
+import "dart:_internal" as _in;
+import "dart:core" as core;
+
+import "dart:_internal";
+
+@#C1
+class Class extends core::Object {
+  final field core::bool defaultValue /* from org-dartlang-testcase:///patch_lib.dart */;
+  static final field dynamic _redirecting# = <dynamic>[#C2]/*isLegacy*/;
+  const constructor _internal({core::bool defaultValue = #C3}) → test::Class
+    : test::Class::defaultValue = defaultValue, super core::Object::•()
+    ;
+  @#C1
+  static factory /* from org-dartlang-testcase:///patch_lib.dart */ fact({core::bool defaultValue = #C4}) → test::Class
+    return new test::Class::_internal(defaultValue: defaultValue);
+  @#C1
+  static factory /* from org-dartlang-testcase:///patch_lib.dart */ constFact({core::bool defaultValue = #C4}) → test::Class
+    return throw "unsupported";
+  @#C1
+  static factory /* from org-dartlang-testcase:///patch_lib.dart */ redirect({core::bool defaultValue = #C4}) → test::Class
+    return new test::Class::_internal(defaultValue: defaultValue);
+}
+
+constants  {
+  #C1 = _in::_Patch {}
+  #C2 = constructor-tearoff test::Class::redirect
+  #C3 = false
+  #C4 = true
+}
diff --git a/pkg/front_end/testcases/general/fallthrough.dart.weak.modular.expect b/pkg/front_end/testcases/general/fallthrough.dart.weak.modular.expect
new file mode 100644
index 0000000..4348081
--- /dev/null
+++ b/pkg/front_end/testcases/general/fallthrough.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/fallthrough.dart:8:5: Error: Switch case may fall through to the next case.
+//     case 3:
+//     ^
+//
+// pkg/front_end/testcases/general/fallthrough.dart:12:5: Error: Switch case may fall through to the next case.
+//     case 6:
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method main(core::List<core::String*>* args) → void {
+  core::int* x = args.{core::List::length}{core::int*};
+  #L1:
+  switch(x) {
+    #L2:
+    case #C1:
+      {
+        x = 4;
+        throw new core::FallThroughError::_create("org-dartlang-testcase:///fallthrough.dart", 8);
+      }
+    #L3:
+    case #C2:
+      {
+        break #L1;
+      }
+    #L4:
+    case #C3:
+    case #C4:
+      {
+        if(args.{core::List::[]}(0){(core::int*) →* core::String*} =={core::String::==}{(core::Object*) →* core::bool*} "") {
+          break #L1;
+        }
+        else {
+          return;
+        }
+        throw new core::FallThroughError::_create("org-dartlang-testcase:///fallthrough.dart", 12);
+      }
+    #L5:
+    case #C5:
+      {}
+  }
+}
+
+constants  {
+  #C1 = 3
+  #C2 = 5
+  #C3 = 6
+  #C4 = 7
+  #C5 = 4
+}
diff --git a/pkg/front_end/testcases/general/ffi_sample.dart.weak.modular.expect b/pkg/front_end/testcases/general/ffi_sample.dart.weak.modular.expect
new file mode 100644
index 0000000..6895041
--- /dev/null
+++ b/pkg/front_end/testcases/general/ffi_sample.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library;
+import self as self;
+import "dart:ffi" as ffi;
+import "dart:core" as core;
+
+import "dart:ffi";
+import "package:ffi/ffi.dart";
+
+class Coordinate extends ffi::Struct {
+  @#C1
+  field core::double* x = null;
+  @#C1
+  field core::double* y = null;
+  field ffi::Pointer<self::Coordinate*>* next = null;
+  static factory allocate(ffi::Allocator* allocator, core::double* x, core::double* y, ffi::Pointer<self::Coordinate*>* next) → self::Coordinate* {
+    return let final self::Coordinate* #t1 = ffi::StructPointer|get#ref<self::Coordinate*>(ffi::AllocatorAlloc|call<self::Coordinate*>(allocator)) in block {
+      #t1.{self::Coordinate::x} = x;
+      #t1.{self::Coordinate::y} = y;
+      #t1.{self::Coordinate::next} = next;
+    } =>#t1;
+  }
+  abstract member-signature get _typedDataBase() → core::Object*; -> ffi::_Compound::_typedDataBase
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = ffi::Double {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///ffi_sample.dart:
+- Double. (from org-dartlang-sdk:///sdk/lib/ffi/native_type.dart:122:9)
+- _NativeDouble. (from org-dartlang-sdk:///sdk/lib/ffi/native_type.dart:34:9)
+- NativeType. (from org-dartlang-sdk:///sdk/lib/ffi/native_type.dart:12:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/fibonacci.dart.weak.modular.expect b/pkg/front_end/testcases/general/fibonacci.dart.weak.modular.expect
new file mode 100644
index 0000000..df2b7da
--- /dev/null
+++ b/pkg/front_end/testcases/general/fibonacci.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method fibonacci(core::int* n) → core::int* {
+  if(n.{core::num::<}(2){(core::num*) →* core::bool*})
+    return n;
+  return self::fibonacci(n.{core::num::-}(1){(core::num*) →* core::int*}).{core::num::+}(self::fibonacci(n.{core::num::-}(2){(core::num*) →* core::int*})){(core::num*) →* core::int*};
+}
+static method main() → dynamic {
+  for (core::int* i = 0; i.{core::num::<}(20){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+    core::print(self::fibonacci(i));
+  }
+}
diff --git a/pkg/front_end/testcases/general/field_initializer_capture_this.dart.weak.modular.expect b/pkg/front_end/testcases/general/field_initializer_capture_this.dart.weak.modular.expect
new file mode 100644
index 0000000..6307537
--- /dev/null
+++ b/pkg/front_end/testcases/general/field_initializer_capture_this.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/field_initializer_capture_this.dart:6:17: Error: Can't access 'this' in a field initializer to read 'x'.
+//   var f = () => x; // error
+//                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field () →* invalid-type f = () → invalid-type => invalid-expression "pkg/front_end/testcases/general/field_initializer_capture_this.dart:6:17: Error: Can't access 'this' in a field initializer to read 'x'.
+  var f = () => x; // error
+                ^";
+  field dynamic x = null;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/final_field_setter.dart.weak.modular.expect b/pkg/front_end/testcases/general/final_field_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..b2023bc
--- /dev/null
+++ b/pkg/front_end/testcases/general/final_field_setter.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  final field core::int* field = 42;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  set field(core::int* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static final field core::int* field = 42;
+static set field(core::int* value) → void {}
+static method main() → dynamic {
+  self::field = self::field;
+  self::Class* c = new self::Class::•();
+  c.{self::Class::field} = self::field;
+}
diff --git a/pkg/front_end/testcases/general/flutter_issue64155.dart.weak.modular.expect b/pkg/front_end/testcases/general/flutter_issue64155.dart.weak.modular.expect
new file mode 100644
index 0000000..5cfbd7c
--- /dev/null
+++ b/pkg/front_end/testcases/general/flutter_issue64155.dart.weak.modular.expect
@@ -0,0 +1,137 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+abstract class TestMixin<R extends core::Object* = dynamic, T extends core::Object* = dynamic> extends core::Object /*isMixinDeclaration*/  {
+  method test(covariant-by-class asy::Future<self::TestMixin::R*>* fetch) → asy::Future<self::TestMixin::T*>* async {
+    final self::TestMixin::R* response = await fetch;
+    self::TestMixin::T* result;
+    if(response is self::Response<dynamic>*) {
+      result = response{self::TestMixin::R* & self::Response<dynamic>* /* '*' & '*' = '*' */}.{self::Response::data}{dynamic} as{TypeError,ForDynamic} self::TestMixin::T*;
+    }
+    else
+      if(response is self::PagingResponse<dynamic>*) {
+        result = response{self::TestMixin::R* & self::PagingResponse<dynamic>* /* '*' & '*' = '*' */}.{self::PagingResponse::data}{self::PagingResponseData<dynamic>*}.{self::PagingResponseData::data}{core::List<dynamic>*} as self::TestMixin::T*;
+      }
+      else
+        if(response is self::TestMixin::T*) {
+          result = response{self::TestMixin::R* & self::TestMixin::T* /* '*' & '*' = '*' */};
+        }
+        else {
+          throw core::Exception::•("Invalid response type");
+        }
+    return result;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class PagingResponse<T extends core::Object* = dynamic> extends core::Object {
+  final field self::PagingResponseData<self::PagingResponse::T*>* data;
+  constructor •(self::PagingResponseData<self::PagingResponse::T*>* data) → self::PagingResponse<self::PagingResponse::T*>*
+    : self::PagingResponse::data = data, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class PagingResponseData<T extends core::Object* = dynamic> extends core::Object {
+  final field core::List<self::PagingResponseData::T*>* data;
+  constructor •(core::List<self::PagingResponseData::T*>* data) → self::PagingResponseData<self::PagingResponseData::T*>*
+    : self::PagingResponseData::data = data, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Response<T extends core::Object* = dynamic> extends core::Object {
+  final field self::Response::T* data;
+  constructor •(self::Response::T* data) → self::Response<self::Response::T*>*
+    : self::Response::data = data, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Class1&Object&TestMixin = core::Object with self::TestMixin<self::Response<core::String*>*, core::String*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Class1&Object&TestMixin*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method test(covariant-by-class asy::Future<self::Response<core::String*>*>* fetch) → asy::Future<core::String*>*
+    return super.{self::TestMixin::test}(fetch);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class1 extends self::_Class1&Object&TestMixin {
+  synthetic constructor •() → self::Class1*
+    : super self::_Class1&Object&TestMixin::•()
+    ;
+  method _test() → dynamic {
+    final self::Response<core::String*>* response = new self::Response::•<core::String*>("test");
+    this.{self::_Class1&Object&TestMixin::test}(asy::Future::value<self::Response<core::String*>*>(response)){(asy::Future<self::Response<core::String*>*>*) →* asy::Future<core::String*>*};
+  }
+}
+abstract class _Class2&Object&TestMixin = core::Object with self::TestMixin<self::PagingResponse<core::String*>*, core::String*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Class2&Object&TestMixin*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method test(covariant-by-class asy::Future<self::PagingResponse<core::String*>*>* fetch) → asy::Future<core::String*>*
+    return super.{self::TestMixin::test}(fetch);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class2 extends self::_Class2&Object&TestMixin {
+  synthetic constructor •() → self::Class2*
+    : super self::_Class2&Object&TestMixin::•()
+    ;
+  method _test() → dynamic {
+    final self::PagingResponse<core::String*>* response = new self::PagingResponse::•<core::String*>(new self::PagingResponseData::•<core::String*>(<core::String*>["test"]));
+    this.{self::_Class2&Object&TestMixin::test}(asy::Future::value<self::PagingResponse<core::String*>*>(response)){(asy::Future<self::PagingResponse<core::String*>*>*) →* asy::Future<core::String*>*};
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/flutter_issue68092/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/flutter_issue68092/main.dart.weak.modular.expect
new file mode 100644
index 0000000..5ba0d07
--- /dev/null
+++ b/pkg/front_end/testcases/general/flutter_issue68092/main.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "main_lib.dart" as mai;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+static method main() → void {
+  function f({core::int* x = #C1}) → core::int*
+    return null;
+  new mai::Registry::•().{mai::DynamicDispatchRegistry::register}(f){(({x: core::int*}) →* core::int*) →* ({x: core::int*}) →* core::int*};
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/for_in_scope.dart.weak.modular.expect b/pkg/front_end/testcases/general/for_in_scope.dart.weak.modular.expect
new file mode 100644
index 0000000..78f359e
--- /dev/null
+++ b/pkg/front_end/testcases/general/for_in_scope.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main(core::List<core::String*>* arguments) → dynamic {
+  for (core::String* arguments in arguments) {
+    core::print(arguments);
+  }
+}
diff --git a/pkg/front_end/testcases/general/for_in_without_declaration.dart.weak.modular.expect b/pkg/front_end/testcases/general/for_in_without_declaration.dart.weak.modular.expect
new file mode 100644
index 0000000..ba021d0
--- /dev/null
+++ b/pkg/front_end/testcases/general/for_in_without_declaration.dart.weak.modular.expect
@@ -0,0 +1,200 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/for_in_without_declaration.dart:32:10: Error: Expected an identifier, but got 'super'.
+// Try inserting an identifier before 'super'.
+//     for (super.superInstanceField in []) {}
+//          ^^^^^
+//
+// pkg/front_end/testcases/general/for_in_without_declaration.dart:33:10: Error: Expected an identifier, but got 'super'.
+// Try inserting an identifier before 'super'.
+//     for (super.untypedSuperInstanceField in []) {}
+//          ^^^^^
+//
+// pkg/front_end/testcases/general/for_in_without_declaration.dart:35:11: Error: Unexpected token '.'.
+//     for (c.instanceField in []) {}
+//           ^
+//
+// pkg/front_end/testcases/general/for_in_without_declaration.dart:36:11: Error: Unexpected token '.'.
+//     for (c.untypedSuperInstanceField in []) {}
+//           ^
+//
+// pkg/front_end/testcases/general/for_in_without_declaration.dart:38:20: Error: Unexpected token '.'.
+//     for (unresolved.foo in []) {}
+//                    ^
+//
+// pkg/front_end/testcases/general/for_in_without_declaration.dart:39:11: Error: Unexpected token '.'.
+//     for (c.unresolved in []) {}
+//           ^
+//
+// pkg/front_end/testcases/general/for_in_without_declaration.dart:40:14: Error: Unexpected token '('.
+//     for (main() in []) {}
+//              ^
+//
+// pkg/front_end/testcases/general/for_in_without_declaration.dart:40:10: Error: Can't assign to this, so it can't be used in a for-in loop.
+//     for (main() in []) {}
+//          ^^^^
+//
+// pkg/front_end/testcases/general/for_in_without_declaration.dart:41:15: Error: Unexpected token ','.
+//     for (var x, y in <int>[]) {
+//               ^
+//
+// pkg/front_end/testcases/general/for_in_without_declaration.dart:41:10: Error: A for-in loop can't have more than one loop variable.
+//     for (var x, y in <int>[]) {
+//          ^^^
+//
+// pkg/front_end/testcases/general/for_in_without_declaration.dart:46:10: Error: Can't assign to the const variable 'constant'.
+//     for (constant in []) {}
+//          ^^^^^^^^
+//
+// pkg/front_end/testcases/general/for_in_without_declaration.dart:37:10: Error: The setter 'unresolved' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/general/for_in_without_declaration.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'unresolved'.
+//     for (unresolved in []) {}
+//          ^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/for_in_without_declaration.dart:38:10: Error: The getter 'unresolved' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/general/for_in_without_declaration.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'unresolved'.
+//     for (unresolved.foo in []) {}
+//          ^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/for_in_without_declaration.dart:39:12: Error: The setter 'unresolved' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/general/for_in_without_declaration.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'unresolved'.
+//     for (c.unresolved in []) {}
+//            ^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  field core::int* superInstanceField = null;
+  field dynamic untypedSuperInstanceField = null;
+  synthetic constructor •() → self::Super*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::Super {
+  field core::int* instanceField = null;
+  field dynamic untypedInstanceField = null;
+  static field core::double* staticField = null;
+  static field dynamic untypedStaticField = null;
+  synthetic constructor •() → self::C*
+    : super self::Super::•()
+    ;
+  method m() → dynamic {
+    core::String* local;
+    dynamic untypedLocal;
+    for (final core::String* #t1 in <core::String*>[]) {
+      local = #t1;
+    }
+    for (final dynamic #t2 in <dynamic>[]) {
+      untypedLocal = #t2;
+    }
+    for (final core::int* #t3 in <core::int*>[]) {
+      this.{self::C::instanceField} = #t3;
+    }
+    for (final dynamic #t4 in <dynamic>[]) {
+      this.{self::C::untypedInstanceField} = #t4;
+    }
+    for (final core::double* #t5 in <core::double*>[]) {
+      self::C::staticField = #t5;
+    }
+    for (final dynamic #t6 in <dynamic>[]) {
+      self::C::untypedStaticField = #t6;
+    }
+    for (final core::bool* #t7 in <core::bool*>[]) {
+      self::topLevelField = #t7;
+    }
+    for (final dynamic #t8 in <dynamic>[]) {
+      self::untypedTopLevelField = #t8;
+    }
+    for (final core::int* #t9 in <core::int*>[]) {
+      super.{self::Super::superInstanceField} = #t9;
+    }
+    for (final dynamic #t10 in <dynamic>[]) {
+      super.{self::Super::untypedSuperInstanceField} = #t10;
+    }
+    self::C* c = new self::C::•();
+    for (final core::int* #t11 in <core::int*>[]) {
+      c.{self::C::instanceField} = #t11;
+    }
+    for (final dynamic #t12 in <dynamic>[]) {
+      c.{self::Super::untypedSuperInstanceField} = #t12;
+    }
+    for (final dynamic #t13 in <dynamic>[]) {
+      invalid-expression "pkg/front_end/testcases/general/for_in_without_declaration.dart:37:10: Error: The setter 'unresolved' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/general/for_in_without_declaration.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'unresolved'.
+    for (unresolved in []) {}
+         ^^^^^^^^^^" in this{<unresolved>}.unresolved = invalid-expression "pkg/front_end/testcases/general/for_in_without_declaration.dart:37:10: Error: The setter 'unresolved' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/general/for_in_without_declaration.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'unresolved'.
+    for (unresolved in []) {}
+         ^^^^^^^^^^";
+    }
+    for (final dynamic #t14 in <dynamic>[]) {
+      invalid-expression "pkg/front_end/testcases/general/for_in_without_declaration.dart:38:10: Error: The getter 'unresolved' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/general/for_in_without_declaration.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'unresolved'.
+    for (unresolved.foo in []) {}
+         ^^^^^^^^^^" in this{<unresolved>}.unresolved{<invalid>}.foo = #t14;
+    }
+    for (final dynamic #t15 in <dynamic>[]) {
+      invalid-expression "pkg/front_end/testcases/general/for_in_without_declaration.dart:39:12: Error: The setter 'unresolved' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/general/for_in_without_declaration.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'unresolved'.
+    for (c.unresolved in []) {}
+           ^^^^^^^^^^" in c{<unresolved>}.unresolved = invalid-expression "pkg/front_end/testcases/general/for_in_without_declaration.dart:39:12: Error: The setter 'unresolved' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/general/for_in_without_declaration.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'unresolved'.
+    for (c.unresolved in []) {}
+           ^^^^^^^^^^";
+    }
+    {
+      invalid-expression "pkg/front_end/testcases/general/for_in_without_declaration.dart:40:10: Error: Can't assign to this, so it can't be used in a for-in loop.
+    for (main() in []) {}
+         ^^^^";
+      for (final dynamic #t16 in <dynamic>[]) {
+        invalid-expression "pkg/front_end/testcases/general/for_in_without_declaration.dart:40:10: Error: Can't assign to this, so it can't be used in a for-in loop.
+    for (main() in []) {}
+         ^^^^";
+        self::main();
+      }
+    }
+    {
+      invalid-expression "pkg/front_end/testcases/general/for_in_without_declaration.dart:41:10: Error: A for-in loop can't have more than one loop variable.
+    for (var x, y in <int>[]) {
+         ^^^";
+      for (final core::int* #t17 in <core::int*>[]) {
+        invalid-expression "pkg/front_end/testcases/general/for_in_without_declaration.dart:41:10: Error: A for-in loop can't have more than one loop variable.
+    for (var x, y in <int>[]) {
+         ^^^";
+        dynamic x;
+        dynamic y;
+        core::print(x);
+        core::print(y);
+      }
+    }
+    for (final dynamic #t18 in <dynamic>[]) {
+      invalid-expression "pkg/front_end/testcases/general/for_in_without_declaration.dart:46:10: Error: Can't assign to the const variable 'constant'.
+    for (constant in []) {}
+         ^^^^^^^^";
+    }
+  }
+}
+static field core::bool* topLevelField;
+static field dynamic untypedTopLevelField;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/forwarding_semi_stub.dart.weak.modular.expect b/pkg/front_end/testcases/general/forwarding_semi_stub.dart.weak.modular.expect
new file mode 100644
index 0000000..f1523c5
--- /dev/null
+++ b/pkg/front_end/testcases/general/forwarding_semi_stub.dart.weak.modular.expect
@@ -0,0 +1,99 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Super<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Super<self::Super::T%>
+    : super core::Object::•()
+    ;
+  method method1(core::int a) → void {}
+  method method2({core::int? a = #C1}) → void {}
+  method method3(core::int a) → void {}
+  method method4(core::num a) → void {}
+  method method5({core::int? a = #C1}) → void {}
+  method method6({core::num? a = #C1}) → void {}
+  method method7(covariant-by-class core::List<self::Super::T%> a) → void {}
+  method method8({covariant-by-class core::List<self::Super::T%>? a = #C1}) → void {}
+  method method9(covariant-by-class core::List<self::Super::T%> a) → void {}
+  method method10(covariant-by-class core::Iterable<self::Super::T%> a) → void {}
+  method method11({covariant-by-class core::List<self::Super::T%>? a = #C1}) → void {}
+  method method12({covariant-by-class core::Iterable<self::Super::T%>? a = #C1}) → void {}
+  set setter1(core::int a) → void {}
+  set setter2(core::num a) → void {}
+  set setter3(covariant-by-class core::List<self::Super::T%> a) → void {}
+  set setter4(covariant-by-class core::Iterable<self::Super::T%> a) → void {}
+}
+class Interface<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Interface<self::Interface::T%>
+    : super core::Object::•()
+    ;
+  method method1(covariant-by-declaration core::num a) → void {}
+  method method2({covariant-by-declaration core::num? a = #C1}) → void {}
+  method method7(covariant-by-declaration covariant-by-class core::Iterable<self::Interface::T%> a) → void {}
+  method method8({covariant-by-declaration covariant-by-class core::Iterable<self::Interface::T%>? a = #C1}) → void {}
+  set setter1(covariant-by-declaration core::num a) → void {}
+  set setter3(covariant-by-declaration covariant-by-class core::Iterable<self::Interface::T%> a) → void {}
+}
+abstract class Class<T extends core::Object? = dynamic> extends self::Super<self::Class::T%> implements self::Interface<self::Class::T%> {
+  synthetic constructor •() → self::Class<self::Class::T%>
+    : super self::Super::•()
+    ;
+  forwarding-stub forwarding-semi-stub method /* signature-type: (core::num) → void */ method3(covariant-by-declaration core::int a) → void
+    return super.{self::Super::method3}(a);
+  forwarding-stub forwarding-semi-stub method /* signature-type: (core::int) → void */ method4(covariant-by-declaration core::num a) → void
+    return super.{self::Super::method4}(a);
+  forwarding-stub forwarding-semi-stub method /* signature-type: ({a: core::num?}) → void */ method5({covariant-by-declaration core::int? a = #C1}) → void
+    return super.{self::Super::method5}(a: a);
+  forwarding-stub forwarding-semi-stub method /* signature-type: ({a: core::int?}) → void */ method6({covariant-by-declaration core::num? a = #C1}) → void
+    return super.{self::Super::method6}(a: a);
+  forwarding-stub forwarding-semi-stub method /* signature-type: (core::Iterable<self::Class::T%>) → void */ method9(covariant-by-declaration covariant-by-class core::List<self::Class::T%> a) → void
+    return super.{self::Super::method9}(a);
+  forwarding-stub forwarding-semi-stub method /* signature-type: (core::List<self::Class::T%>) → void */ method10(covariant-by-declaration covariant-by-class core::Iterable<self::Class::T%> a) → void
+    return super.{self::Super::method10}(a);
+  forwarding-stub forwarding-semi-stub method /* signature-type: ({a: core::Iterable<self::Class::T%>?}) → void */ method11({covariant-by-declaration covariant-by-class core::List<self::Class::T%>? a = #C1}) → void
+    return super.{self::Super::method11}(a: a);
+  forwarding-stub forwarding-semi-stub method /* signature-type: ({a: core::List<self::Class::T%>?}) → void */ method12({covariant-by-declaration covariant-by-class core::Iterable<self::Class::T%>? a = #C1}) → void
+    return super.{self::Super::method12}(a: a);
+  forwarding-stub forwarding-semi-stub set /* signature-type: (core::int) → void */ setter2(covariant-by-declaration core::num a) → void
+    return super.{self::Super::setter2} = a;
+  forwarding-stub forwarding-semi-stub set /* signature-type: (core::List<self::Class::T%>) → void */ setter4(covariant-by-declaration covariant-by-class core::Iterable<self::Class::T%> a) → void
+    return super.{self::Super::setter4} = a;
+  forwarding-stub method method1(covariant-by-declaration core::num a) → void
+    return super.{self::Super::method1}(a as core::int);
+  forwarding-stub method method2({covariant-by-declaration core::num? a = #C1}) → void
+    return super.{self::Super::method2}(a: a as core::int?);
+  forwarding-stub method method7(covariant-by-declaration covariant-by-class core::Iterable<self::Class::T%> a) → void
+    return super.{self::Super::method7}(a as core::List<self::Class::T%>);
+  forwarding-stub method method8({covariant-by-declaration covariant-by-class core::Iterable<self::Class::T%>? a = #C1}) → void
+    return super.{self::Super::method8}(a: a as core::List<self::Class::T%>?);
+  forwarding-stub set setter1(covariant-by-declaration core::num a) → void
+    return super.{self::Super::setter1} = a as core::int;
+  forwarding-stub set setter3(covariant-by-declaration covariant-by-class core::Iterable<self::Class::T%> a) → void
+    return super.{self::Super::setter3} = a as core::List<self::Class::T%>;
+}
+class Subclass<T extends core::Object? = dynamic> extends self::Class<self::Subclass::T%> {
+  synthetic constructor •() → self::Subclass<self::Subclass::T%>
+    : super self::Class::•()
+    ;
+  method method1(covariant-by-declaration core::num a) → void {}
+  method method2({covariant-by-declaration core::num? a = #C1}) → void {}
+  method method3(covariant-by-declaration core::num a) → void {}
+  method method4(covariant-by-declaration core::num a) → void {}
+  method method5({covariant-by-declaration core::num? a = #C1}) → void {}
+  method method6({covariant-by-declaration core::num? a = #C1}) → void {}
+  method method7(covariant-by-declaration covariant-by-class core::Iterable<self::Subclass::T%> a) → void {}
+  method method8({covariant-by-declaration covariant-by-class core::Iterable<self::Subclass::T%>? a = #C1}) → void {}
+  method method9(covariant-by-declaration covariant-by-class core::Iterable<self::Subclass::T%> a) → void {}
+  method method10(covariant-by-declaration covariant-by-class core::Iterable<self::Subclass::T%> a) → void {}
+  method method11({covariant-by-declaration covariant-by-class core::Iterable<self::Subclass::T%>? a = #C1}) → void {}
+  method method12({covariant-by-declaration covariant-by-class core::Iterable<self::Subclass::T%>? a = #C1}) → void {}
+  set setter1(covariant-by-declaration core::num a) → void {}
+  set setter2(covariant-by-declaration core::num a) → void {}
+  set setter3(covariant-by-declaration covariant-by-class core::Iterable<self::Subclass::T%> a) → void {}
+  set setter4(covariant-by-declaration covariant-by-class core::Iterable<self::Subclass::T%> a) → void {}
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/forwarding_stub_for_operator.dart.weak.modular.expect b/pkg/front_end/testcases/general/forwarding_stub_for_operator.dart.weak.modular.expect
new file mode 100644
index 0000000..6b4bf1c
--- /dev/null
+++ b/pkg/front_end/testcases/general/forwarding_stub_for_operator.dart.weak.modular.expect
@@ -0,0 +1,79 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator +(covariant-by-declaration core::int* a) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  operator +(dynamic b) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object implements self::A, self::B {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract forwarding-stub operator +(covariant-by-declaration dynamic b) → dynamic;
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  operator +(dynamic d) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E extends self::D {
+  synthetic constructor •() → self::E*
+    : super self::D::•()
+    ;
+  forwarding-stub forwarding-semi-stub operator /* signature-type: (core::int*) →* dynamic */ +(covariant-by-declaration dynamic e) → dynamic
+    return super.{self::D::+}(e);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/function_bad_use.dart.weak.modular.expect b/pkg/front_end/testcases/general/function_bad_use.dart.weak.modular.expect
new file mode 100644
index 0000000..044f5c0
--- /dev/null
+++ b/pkg/front_end/testcases/general/function_bad_use.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/function_bad_use.dart:1:7: Error: 'Function' is a built-in identifier, could not used as a class name.
+// class Function {}
+//       ^^^^^^^^
+//
+// pkg/front_end/testcases/general/function_bad_use.dart:3:9: Error: 'Function' is a built-in identifier, could not used as a type identifier.
+// class C<Function> {}
+//         ^^^^^^^^
+//
+// pkg/front_end/testcases/general/function_bad_use.dart:5:9: Error: 'Function' is a built-in identifier, could not used as a type identifier.
+// mixin M<Function> implements List<Function> {}
+//         ^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Function extends core::Object {
+  synthetic constructor •() → self::Function
+    : super core::Object::•()
+    ;
+}
+class C<Function extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::Function%>
+    : super core::Object::•()
+    ;
+}
+abstract class M<Function extends core::Object? = dynamic> extends core::Object implements core::List<self::M::Function%> /*isMixinDeclaration*/  {
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/function_call1.dart.weak.modular.expect b/pkg/front_end/testcases/general/function_call1.dart.weak.modular.expect
new file mode 100644
index 0000000..c5b503d
--- /dev/null
+++ b/pkg/front_end/testcases/general/function_call1.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/function_call1.dart:16:6: Error: Cannot invoke an instance of '_Closure1' because it declares 'call' to be something other than a method.
+//  - '_Closure1' is from 'pkg/front_end/testcases/general/function_call1.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+//   foo();
+//      ^
+//
+// pkg/front_end/testcases/general/function_call1.dart:17:6: Error: Cannot invoke an instance of '_Closure2' because it declares 'call' to be something other than a method.
+//  - '_Closure2' is from 'pkg/front_end/testcases/general/function_call1.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+//   bar();
+//      ^
+//
+// pkg/front_end/testcases/general/function_call1.dart:23:22: Error: Cannot invoke an instance of '_Closure1' because it declares 'call' to be something other than a method.
+//  - '_Closure1' is from 'pkg/front_end/testcases/general/function_call1.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+// var field1 = closure1();
+//                      ^
+//
+// pkg/front_end/testcases/general/function_call1.dart:24:22: Error: Cannot invoke an instance of '_Closure2' because it declares 'call' to be something other than a method.
+//  - '_Closure2' is from 'pkg/front_end/testcases/general/function_call1.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+// var field2 = closure2();
+//                      ^
+//
+import self as self;
+import "dart:core" as core;
+
+class _Closure1 extends core::Object {
+  synthetic constructor •() → self::_Closure1
+    : super core::Object::•()
+    ;
+  get call() → self::_Closure1
+    return this;
+}
+class _Closure2 extends core::Object {
+  final field self::_Closure2 call;
+  constructor •(self::_Closure2 call) → self::_Closure2
+    : self::_Closure2::call = call, super core::Object::•()
+    ;
+}
+late static field self::_Closure1 closure1;
+late static field self::_Closure2 closure2;
+static field invalid-type field1 = invalid-expression "pkg/front_end/testcases/general/function_call1.dart:23:22: Error: Cannot invoke an instance of '_Closure1' because it declares 'call' to be something other than a method.
+ - '_Closure1' is from 'pkg/front_end/testcases/general/function_call1.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+var field1 = closure1();
+                     ^";
+static field invalid-type field2 = invalid-expression "pkg/front_end/testcases/general/function_call1.dart:24:22: Error: Cannot invoke an instance of '_Closure2' because it declares 'call' to be something other than a method.
+ - '_Closure2' is from 'pkg/front_end/testcases/general/function_call1.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+var field2 = closure2();
+                     ^";
+static method test(self::_Closure1 foo, self::_Closure2 bar) → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/function_call1.dart:16:6: Error: Cannot invoke an instance of '_Closure1' because it declares 'call' to be something other than a method.
+ - '_Closure1' is from 'pkg/front_end/testcases/general/function_call1.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+  foo();
+     ^";
+  invalid-expression "pkg/front_end/testcases/general/function_call1.dart:17:6: Error: Cannot invoke an instance of '_Closure2' because it declares 'call' to be something other than a method.
+ - '_Closure2' is from 'pkg/front_end/testcases/general/function_call1.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+  bar();
+     ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/function_call2.dart.weak.modular.expect b/pkg/front_end/testcases/general/function_call2.dart.weak.modular.expect
new file mode 100644
index 0000000..c0f6881
--- /dev/null
+++ b/pkg/front_end/testcases/general/function_call2.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/function_call2.dart:16:6: Error: Cannot invoke an instance of '_Closure1' because it declares 'call' to be something other than a method.
+//  - '_Closure1' is from 'pkg/front_end/testcases/general/function_call2.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+//   foo();
+//      ^
+//
+// pkg/front_end/testcases/general/function_call2.dart:17:6: Error: Cannot invoke an instance of '_Closure2' because it declares 'call' to be something other than a method.
+//  - '_Closure2' is from 'pkg/front_end/testcases/general/function_call2.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+//   bar();
+//      ^
+//
+// pkg/front_end/testcases/general/function_call2.dart:23:22: Error: Cannot invoke an instance of '_Closure1' because it declares 'call' to be something other than a method.
+//  - '_Closure1' is from 'pkg/front_end/testcases/general/function_call2.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+// var field1 = closure1();
+//                      ^
+//
+// pkg/front_end/testcases/general/function_call2.dart:24:22: Error: Cannot invoke an instance of '_Closure2' because it declares 'call' to be something other than a method.
+//  - '_Closure2' is from 'pkg/front_end/testcases/general/function_call2.dart'.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+// var field2 = closure2();
+//                      ^
+//
+import self as self;
+import "dart:core" as core;
+
+class _Closure1 extends core::Object {
+  synthetic constructor •() → self::_Closure1
+    : super core::Object::•()
+    ;
+  get call() → () → void
+    return () → void {};
+}
+class _Closure2 extends core::Object {
+  final field () → void call;
+  constructor •(() → void call) → self::_Closure2
+    : self::_Closure2::call = call, super core::Object::•()
+    ;
+}
+late static field self::_Closure1 closure1;
+late static field self::_Closure2 closure2;
+static field invalid-type field1 = invalid-expression "pkg/front_end/testcases/general/function_call2.dart:23:22: Error: Cannot invoke an instance of '_Closure1' because it declares 'call' to be something other than a method.
+ - '_Closure1' is from 'pkg/front_end/testcases/general/function_call2.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+var field1 = closure1();
+                     ^";
+static field invalid-type field2 = invalid-expression "pkg/front_end/testcases/general/function_call2.dart:24:22: Error: Cannot invoke an instance of '_Closure2' because it declares 'call' to be something other than a method.
+ - '_Closure2' is from 'pkg/front_end/testcases/general/function_call2.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+var field2 = closure2();
+                     ^";
+static method test(self::_Closure1 foo, self::_Closure2 bar) → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/function_call2.dart:16:6: Error: Cannot invoke an instance of '_Closure1' because it declares 'call' to be something other than a method.
+ - '_Closure1' is from 'pkg/front_end/testcases/general/function_call2.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+  foo();
+     ^";
+  invalid-expression "pkg/front_end/testcases/general/function_call2.dart:17:6: Error: Cannot invoke an instance of '_Closure2' because it declares 'call' to be something other than a method.
+ - '_Closure2' is from 'pkg/front_end/testcases/general/function_call2.dart'.
+Try changing 'call' to a method or explicitly invoke 'call'.
+  bar();
+     ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/function_in_field.dart.weak.modular.expect b/pkg/front_end/testcases/general/function_in_field.dart.weak.modular.expect
new file mode 100644
index 0000000..a2c6a44
--- /dev/null
+++ b/pkg/front_end/testcases/general/function_in_field.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static field () →* core::int* x = () → core::int* {
+  core::int* y = 42;
+  return y;
+};
+static method main() → dynamic {
+  core::print(self::x(){() →* core::int*});
+}
diff --git a/pkg/front_end/testcases/general/function_invocation_bounds.dart.weak.modular.expect b/pkg/front_end/testcases/general/function_invocation_bounds.dart.weak.modular.expect
new file mode 100644
index 0000000..c7ced86
--- /dev/null
+++ b/pkg/front_end/testcases/general/function_invocation_bounds.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/function_invocation_bounds.dart:9:8: Error: Inferred type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'local'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   local("");
+//        ^
+//
+// pkg/front_end/testcases/general/function_invocation_bounds.dart:10:8: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'local'.
+// Try changing type arguments so that they conform to the bounds.
+//   local<String>(throw '');
+//        ^
+//
+// pkg/front_end/testcases/general/function_invocation_bounds.dart:13:8: Error: Expected 1 type arguments.
+//   local<int, String>(throw '');
+//        ^
+//
+// pkg/front_end/testcases/general/function_invocation_bounds.dart:15:4: Error: Inferred type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'call'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   f("");
+//    ^
+//
+// pkg/front_end/testcases/general/function_invocation_bounds.dart:16:4: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'call'.
+// Try changing type arguments so that they conform to the bounds.
+//   f<String>(throw '');
+//    ^
+//
+// pkg/front_end/testcases/general/function_invocation_bounds.dart:19:4: Error: Expected 1 type arguments.
+//   f<int, String>(throw '');
+//    ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef G<invariant T extends core::Object? = dynamic> = (T%) → T%;
+static method test() → dynamic {
+  function local<T extends core::num>(T t) → T
+    return t;
+  local<core::String>(""){(core::String) → core::String};
+  local<core::String>(throw ""){(core::String) → core::String};
+  local<core::int>(0){(core::int) → core::int};
+  local<core::int>(throw ""){(core::int) → core::int};
+  invalid-expression "pkg/front_end/testcases/general/function_invocation_bounds.dart:13:8: Error: Expected 1 type arguments.
+  local<int, String>(throw '');
+       ^" in local{<inapplicable>}.<core::int, core::String>(throw "");
+  <T extends core::num>(T) → T f = local;
+  f<core::String>(""){(core::String) → core::String};
+  f<core::String>(throw ""){(core::String) → core::String};
+  f<core::int>(0){(core::int) → core::int};
+  f<core::int>(throw ""){(core::int) → core::int};
+  invalid-expression "pkg/front_end/testcases/general/function_invocation_bounds.dart:19:4: Error: Expected 1 type arguments.
+  f<int, String>(throw '');
+   ^" in f{<inapplicable>}.<core::int, core::String>(throw "");
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/function_type_assignments.dart.weak.modular.expect b/pkg/front_end/testcases/general/function_type_assignments.dart.weak.modular.expect
new file mode 100644
index 0000000..0333159
--- /dev/null
+++ b/pkg/front_end/testcases/general/function_type_assignments.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/function_type_assignments.dart:11:12: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'String'.
+// String x = identity; // No bound
+//            ^
+//
+// pkg/front_end/testcases/general/function_type_assignments.dart:12:12: Error: A value of type 'T Function<T extends Object>(T)' can't be assigned to a variable of type 'String'.
+//  - 'Object' is from 'dart:core'.
+// String y = identityObject; // Object bound
+//            ^
+//
+// pkg/front_end/testcases/general/function_type_assignments.dart:13:12: Error: A value of type 'T Function<T extends List<T>>(T)' can't be assigned to a variable of type 'String'.
+//  - 'List' is from 'dart:core'.
+// String z = identityList; // List<T> bound
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field core::String* x = invalid-expression "pkg/front_end/testcases/general/function_type_assignments.dart:11:12: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'String'.
+String x = identity; // No bound
+           ^" in #C1 as{TypeError} core::String*;
+static field core::String* y = invalid-expression "pkg/front_end/testcases/general/function_type_assignments.dart:12:12: Error: A value of type 'T Function<T extends Object>(T)' can't be assigned to a variable of type 'String'.
+ - 'Object' is from 'dart:core'.
+String y = identityObject; // Object bound
+           ^" in #C2 as{TypeError} core::String*;
+static field core::String* z = invalid-expression "pkg/front_end/testcases/general/function_type_assignments.dart:13:12: Error: A value of type 'T Function<T extends List<T>>(T)' can't be assigned to a variable of type 'String'.
+ - 'List' is from 'dart:core'.
+String z = identityList; // List<T> bound
+           ^" in #C3 as{TypeError} core::String*;
+static method identity<T extends core::Object* = dynamic>(self::identity::T* t) → self::identity::T*
+  return t;
+static method identityObject<T extends core::Object*>(self::identityObject::T* t) → self::identityObject::T*
+  return t;
+static method identityList<T extends core::List<self::identityList::T*>* = core::List<dynamic>*>(self::identityList::T* t) → self::identityList::T*
+  return t;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::identity
+  #C2 = static-tearoff self::identityObject
+  #C3 = static-tearoff self::identityList
+}
diff --git a/pkg/front_end/testcases/general/function_type_default_value.dart.weak.modular.expect b/pkg/front_end/testcases/general/function_type_default_value.dart.weak.modular.expect
new file mode 100644
index 0000000..37aef15
--- /dev/null
+++ b/pkg/front_end/testcases/general/function_type_default_value.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/function_type_default_value.dart:5:19: Error: Expected an identifier, but got ':'.
+// Try inserting an identifier before ':'.
+// void Function({obj: Object}) x;
+//                   ^
+//
+// pkg/front_end/testcases/general/function_type_default_value.dart:5:19: Error: Can't have a default value in a function type.
+// void Function({obj: Object}) x;
+//                   ^
+//
+// pkg/front_end/testcases/general/function_type_default_value.dart:5:16: Error: Type 'obj' not found.
+// void Function({obj: Object}) x;
+//                ^^^
+//
+// pkg/front_end/testcases/general/function_type_default_value.dart:5:16: Error: 'obj' isn't a type.
+// void Function({obj: Object}) x;
+//                ^^^
+//
+import self as self;
+
+static field () →* void x;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/function_type_is_check.dart.weak.modular.expect b/pkg/front_end/testcases/general/function_type_is_check.dart.weak.modular.expect
new file mode 100644
index 0000000..3994837
--- /dev/null
+++ b/pkg/front_end/testcases/general/function_type_is_check.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart" show Expect;
+
+static method test(dynamic f) → dynamic {
+  if(f is (core::Object*, core::StackTrace*) →* void)
+    return 1;
+  if(f is (core::Object*) →* void)
+    return 10;
+  if(f is () →* void)
+    return 100;
+}
+static method main() → dynamic {
+  exp::Expect::equals(111, self::test(() → Null => null){dynamic}.+(self::test((core::Object* o) → Null => null)){dynamic}.+(self::test((core::Object* o, core::StackTrace* t) → Null => null)));
+}
diff --git a/pkg/front_end/testcases/general/function_type_parameter.dart.weak.modular.expect b/pkg/front_end/testcases/general/function_type_parameter.dart.weak.modular.expect
new file mode 100644
index 0000000..9c2602d
--- /dev/null
+++ b/pkg/front_end/testcases/general/function_type_parameter.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/function_type_parameter.dart:11:20: Error: A type variable on a function type can't have annotations.
+// void Function<@A() T>(T)? f;
+//                    ^
+//
+// pkg/front_end/testcases/general/function_type_parameter.dart:13:32: Error: A type variable on a function type can't have annotations.
+// typedef F = void Function<@A() T>(T);
+//                                ^
+//
+// pkg/front_end/testcases/general/function_type_parameter.dart:19:33: Error: A type variable on a function type can't have annotations.
+// void method2(void Function<@A() T>(T) f) {}
+//                                 ^
+//
+// pkg/front_end/testcases/general/function_type_parameter.dart:21:42: Error: A type variable on a function type can't have annotations.
+// class Class<T extends void Function<@A() S>(S)> {}
+//                                          ^
+//
+// pkg/front_end/testcases/general/function_type_parameter.dart:21:13: Error: Type variables can't have generic function types in their bounds.
+// class Class<T extends void Function<@A() S>(S)> {}
+//             ^
+//
+// pkg/front_end/testcases/general/function_type_parameter.dart:26:22: Error: A type variable on a function type can't have annotations.
+//   void Function<@A() T>(T)? f;
+//                      ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F = <T extends core::Object? = dynamic>(T%) → void;
+typedef G<@#C1 contravariant T extends core::Object? = dynamic> = (T%) → void;
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class Class<T extends <S extends core::Object? = dynamic>(S%) → void = dynamic> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::T>
+    : super core::Object::•()
+    ;
+}
+static field <T extends core::Object? = dynamic>(T%) →? void f;
+static method method1<@#C1 T extends core::Object? = dynamic>(self::method1::T% t) → void {}
+static method method2(<T extends core::Object? = dynamic>(T%) → void f) → void {}
+static method main() → dynamic {
+  function local<@#C1 T extends core::Object? = dynamic>(T% t) → void {}
+  <T extends core::Object? = dynamic>(T%) →? void f;
+}
+
+constants  {
+  #C1 = self::A {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///function_type_parameter.dart:
+- A. (from org-dartlang-testcase:///function_type_parameter.dart:8:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/function_type_recovery.dart.weak.modular.expect b/pkg/front_end/testcases/general/function_type_recovery.dart.weak.modular.expect
new file mode 100644
index 0000000..b221bcb
--- /dev/null
+++ b/pkg/front_end/testcases/general/function_type_recovery.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/function_type_recovery.dart:8:31: Error: Inline function types cannot be used for parameters in a generic function type.
+// Try changing the inline function type (as in 'int f()') to a prefixed function type using the `Function` keyword (as in 'int Function() f').
+// typedef F = int Function(int f(String x));
+//                               ^
+//
+// pkg/front_end/testcases/general/function_type_recovery.dart:12:27: Error: Inline function types cannot be used for parameters in a generic function type.
+// Try changing the inline function type (as in 'int f()') to a prefixed function type using the `Function` keyword (as in 'int Function() f').
+//   String Function(String g(int y)) g = null;
+//                           ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F = ((core::String*) →* core::int*) →* core::int*;
+static method main() → dynamic {
+  ((core::String*) →* core::int*) →* core::int* f = null;
+  ((core::int*) →* core::String*) →* core::String* g = null;
+}
diff --git a/pkg/front_end/testcases/general/functions.dart.weak.modular.expect b/pkg/front_end/testcases/general/functions.dart.weak.modular.expect
new file mode 100644
index 0000000..a0fd727
--- /dev/null
+++ b/pkg/front_end/testcases/general/functions.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  function local(({a: dynamic}) →* void f) → void {
+    f(a: "Hello, World"){({a: dynamic}) →* void};
+    f(){({a: dynamic}) →* void};
+  }
+  local(({dynamic a = #C1}) → Null {
+    core::print(a);
+  }){(({a: dynamic}) →* void) →* void};
+}
+
+constants  {
+  #C1 = "Default greeting!"
+}
diff --git a/pkg/front_end/testcases/general/future_or_null.dart.weak.modular.expect b/pkg/front_end/testcases/general/future_or_null.dart.weak.modular.expect
new file mode 100644
index 0000000..040f77f
--- /dev/null
+++ b/pkg/front_end/testcases/general/future_or_null.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library;
+import self as self;
+
+import "dart:async";
+
+static get foo() → FutureOr<Null>*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/future_or_test.dart.weak.modular.expect b/pkg/front_end/testcases/general/future_or_test.dart.weak.modular.expect
new file mode 100644
index 0000000..cc061fb
--- /dev/null
+++ b/pkg/front_end/testcases/general/future_or_test.dart.weak.modular.expect
@@ -0,0 +1,61 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  field self::A* a = null;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method bar() → asy::Future<dynamic>* async 
+    return this.{self::B::a}{self::A*}.{self::A::foo}(){() →* dynamic};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  field self::B* b = new self::B::•();
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method baz() → asy::Future<core::int*>* async 
+    return this.{self::C::b}{self::B*}.{self::B::bar}(){() →* asy::Future<dynamic>*} as{TypeError} FutureOr<core::int*>*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/future_return.dart.weak.modular.expect b/pkg/front_end/testcases/general/future_return.dart.weak.modular.expect
new file mode 100644
index 0000000..3514a60
--- /dev/null
+++ b/pkg/front_end/testcases/general/future_return.dart.weak.modular.expect
@@ -0,0 +1,81 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/future_return.dart:11:7: Error: Functions marked 'async' must have a return type assignable to 'Future'.
+// Class returnClass() async => new Class();
+//       ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/future_return.dart:17:7: Error: Functions marked 'async' must have a return type assignable to 'Future'.
+// Class returnClassFromDynamic() async => returnDynamic();
+//       ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/future_return.dart:23:7: Error: Functions marked 'async' must have a return type assignable to 'Future'.
+// Class returnClassFromFutureClass() async => returnFutureClass();
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/future_return.dart:30:7: Error: Functions marked 'async' must have a return type assignable to 'Future'.
+// Class returnClassFromFutureOrClass() async => returnFutureOrClass();
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method returnDynamic() → dynamic
+  return new self::Class::•();
+static method returnClass() → self::Class* async 
+  return new self::Class::•();
+static method returnFutureClass() → asy::Future<self::Class*>* async 
+  return new self::Class::•();
+static method returnFutureOrClass() → FutureOr<self::Class*>* async 
+  return new self::Class::•();
+static method returnClassFromDynamic() → self::Class* async 
+  return self::returnDynamic() as{TypeError} FutureOr<self::Class*>*;
+static method returnFutureClassDynamic() → asy::Future<self::Class*>* async 
+  return self::returnDynamic() as{TypeError} FutureOr<self::Class*>*;
+static method returnFutureOrClassDynamic() → FutureOr<self::Class*>* async 
+  return self::returnDynamic() as{TypeError} FutureOr<self::Class*>*;
+static method returnClassFromFutureClass() → self::Class* async 
+  return self::returnFutureClass();
+static method returnFutureClassFromFutureClass() → asy::Future<self::Class*>* async 
+  return self::returnFutureClass();
+static method returnFutureOrClassFromFutureClass() → FutureOr<self::Class*>* async 
+  return self::returnFutureClass();
+static method returnClassFromFutureOrClass() → self::Class* async 
+  return self::returnFutureOrClass();
+static method returnFutureClassFromFutureOrClass() → asy::Future<self::Class*>* async 
+  return self::returnFutureOrClass();
+static method returnFutureOrClassFromFutureOrClass() → FutureOr<self::Class*>* async 
+  return self::returnFutureOrClass();
+static method main() → dynamic async {
+  await self::returnClass();
+  await self::returnFutureClass();
+  await self::returnFutureOrClass();
+  await self::returnClassFromDynamic();
+  await self::returnFutureClassDynamic();
+  await self::returnFutureOrClassDynamic();
+  await self::returnClassFromFutureClass();
+  await self::returnFutureClassFromFutureClass();
+  await self::returnFutureOrClassFromFutureClass();
+  await self::returnClassFromFutureOrClass();
+  await self::returnFutureClassFromFutureOrClass();
+  await self::returnFutureOrClassFromFutureOrClass();
+}
diff --git a/pkg/front_end/testcases/general/generic_function_type_in_message.dart.weak.modular.expect b/pkg/front_end/testcases/general/generic_function_type_in_message.dart.weak.modular.expect
new file mode 100644
index 0000000..20b824e
--- /dev/null
+++ b/pkg/front_end/testcases/general/generic_function_type_in_message.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/generic_function_type_in_message.dart:8:11: Error: A value of type 'num Function<A extends num, B extends num>(A, B)' can't be assigned to a variable of type 'int'.
+//   int x = add;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method add<A extends core::num*, B extends core::num*>(self::add::A* a, self::add::B* b) → core::num*
+  return a.{core::num::+}(b){(core::num*) →* core::num*};
+static method test() → dynamic {
+  core::int* x = invalid-expression "pkg/front_end/testcases/general/generic_function_type_in_message.dart:8:11: Error: A value of type 'num Function<A extends num, B extends num>(A, B)' can't be assigned to a variable of type 'int'.
+  int x = add;
+          ^" in #C1 as{TypeError} core::int*;
+}
+static method main() → dynamic {
+  if(self::add<core::int*, core::int*>(1, 2).{core::num::<}(3){(core::num*) →* core::bool*})
+    self::test();
+}
+
+constants  {
+  #C1 = static-tearoff self::add
+}
diff --git a/pkg/front_end/testcases/general/generic_function_typedef.dart.weak.modular.expect b/pkg/front_end/testcases/general/generic_function_typedef.dart.weak.modular.expect
new file mode 100644
index 0000000..509ac9e
--- /dev/null
+++ b/pkg/front_end/testcases/general/generic_function_typedef.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef E1<unrelated T extends core::Object* = dynamic> = () →* void;
+typedef E2<unrelated T extends core::num*> = () →* void;
+typedef E3<unrelated T extends core::Object* = dynamic, unrelated S extends core::Object* = dynamic> = () →* void;
+typedef E4<unrelated T extends core::num*, unrelated S extends core::num*> = () →* void;
+typedef E5<unrelated T extends S* = core::num*, unrelated S extends core::num*> = () →* void;
+typedef E6<unrelated T extends core::num*, unrelated S extends T* = core::num*> = () →* void;
+typedef F1 = <T extends core::Object* = dynamic>() →* void;
+typedef F2 = <T extends core::num* = dynamic>() →* void;
+typedef F3 = <T extends core::Object* = dynamic, S extends core::Object* = dynamic>() →* void;
+typedef F4 = <T extends core::num* = dynamic, S extends core::num* = dynamic>() →* void;
+typedef F5 = <T extends S* = dynamic, S extends core::num* = dynamic>() →* void;
+typedef F6 = <T extends core::num* = dynamic, S extends T* = dynamic>() →* void;
+typedef G1<invariant X extends core::Object* = dynamic> = <T extends X* = dynamic>() →* void;
+typedef G2<invariant X extends core::num*> = <T extends X* = dynamic>() →* void;
+typedef G3<invariant X extends core::Object* = dynamic, invariant Y extends core::Object* = dynamic> = <T extends X* = dynamic, S extends Y* = dynamic>() →* void;
+typedef G4<invariant X extends core::num*, invariant Y extends core::num*> = <T extends X* = dynamic, S extends Y* = dynamic>() →* void;
+typedef G5<invariant X extends core::num*> = <T extends S* = dynamic, S extends X* = dynamic>() →* void;
+typedef G6<invariant X extends core::num*> = <T extends X* = dynamic, S extends T* = dynamic>() →* void;
+typedef H1 = (<T extends core::Object* = dynamic>() →* void) →* void;
+typedef H2 = (<T extends core::num* = dynamic>() →* void) →* void;
+typedef H3 = (<T extends core::Object* = dynamic, S extends core::Object* = dynamic>() →* void) →* void;
+typedef H4 = (<T extends core::num* = dynamic, S extends core::num* = dynamic>() →* void) →* void;
+typedef H5 = (<T extends S* = dynamic, S extends core::num* = dynamic>() →* void) →* void;
+typedef H6 = (<T extends core::num* = dynamic, S extends T* = dynamic>() →* void) →* void;
+static field <T extends core::Object* = dynamic>() →* void f1;
+static field <T extends core::num* = dynamic>() →* void f2;
+static field <T extends core::Object* = dynamic, S extends core::Object* = dynamic>() →* void f3;
+static field <T extends core::num* = dynamic, S extends core::num* = dynamic>() →* void f4;
+static field <T extends S* = dynamic, S extends core::num* = dynamic>() →* void f5;
+static field <T extends core::num* = dynamic, S extends T* = dynamic>() →* void f6;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/generic_typedef_in_generic_class.dart.weak.modular.expect b/pkg/front_end/testcases/general/generic_typedef_in_generic_class.dart.weak.modular.expect
new file mode 100644
index 0000000..9a41483
--- /dev/null
+++ b/pkg/front_end/testcases/general/generic_typedef_in_generic_class.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef F = <T extends core::Object? = dynamic, S extends core::Object? = dynamic>(T%, S%) → T%;
+class Class<A extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::A%>
+    : super core::Object::•()
+    ;
+  method method() → dynamic {
+    core::print(#C1);
+    core::print(#C1);
+  }
+}
+static method main() → dynamic {
+  new self::Class::•<core::int>().{self::Class::method}(){() → dynamic};
+}
+
+constants  {
+  #C1 = TypeLiteralConstant(<T extends core::Object? = dynamic, S extends core::Object? = dynamic>(T*, S*) →* T*)
+}
diff --git a/pkg/front_end/testcases/general/getter_call.dart.weak.modular.expect b/pkg/front_end/testcases/general/getter_call.dart.weak.modular.expect
new file mode 100644
index 0000000..bcf489c
--- /dev/null
+++ b/pkg/front_end/testcases/general/getter_call.dart.weak.modular.expect
@@ -0,0 +1,187 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::Function* field1a = #C1;
+  field () →* core::int* field1b = #C1;
+  field (core::int*) →* core::int* field2 = #C2;
+  field (core::int*, core::int*) →* core::int* field3 = #C3;
+  field (core::int*, [core::int*]) →* core::int* field4 = #C4;
+  field ([core::int*, core::int*]) →* core::int* field5 = #C5;
+  field (core::int*, {b: core::int*}) →* core::int* field6 = #C6;
+  field ({a: core::int*, b: core::int*}) →* core::int* field7 = #C7;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  get getter1a() → core::Function*
+    return #C1;
+  get getter1b() → () →* core::int*
+    return #C1;
+  get getter2() → (core::int*) →* core::int*
+    return #C2;
+  get getter3() → (core::int*, core::int*) →* core::int*
+    return #C3;
+  get getter4() → (core::int*, [core::int*]) →* core::int*
+    return #C4;
+  get getter5() → ([core::int*, core::int*]) →* core::int*
+    return #C5;
+  get getter6() → (core::int*, {b: core::int*}) →* core::int*
+    return #C6;
+  get getter7() → ({a: core::int*, b: core::int*}) →* core::int*
+    return #C7;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Subclass extends self::Class {
+  synthetic constructor •() → self::Subclass*
+    : super self::Class::•()
+    ;
+  get field1a() → core::Function* {
+    self::enableRead = false;
+    return #C1;
+  }
+  get field1b() → () →* core::int* {
+    self::enableRead = false;
+    return #C1;
+  }
+  get field2() → (core::int*) →* core::int* {
+    self::enableRead = false;
+    return #C2;
+  }
+  get field3() → (core::int*, core::int*) →* core::int* {
+    self::enableRead = false;
+    return #C3;
+  }
+  get field4() → (core::int*, [core::int*]) →* core::int* {
+    self::enableRead = false;
+    return #C4;
+  }
+  get field5() → ([core::int*, core::int*]) →* core::int* {
+    self::enableRead = false;
+    return #C5;
+  }
+  get field6() → (core::int*, {b: core::int*}) →* core::int* {
+    self::enableRead = false;
+    return #C6;
+  }
+  get field7() → ({a: core::int*, b: core::int*}) →* core::int* {
+    self::enableRead = false;
+    return #C7;
+  }
+  get getter1a() → core::Function* {
+    self::enableRead = false;
+    return #C1;
+  }
+  get getter1b() → () →* core::int* {
+    self::enableRead = false;
+    return #C1;
+  }
+  get getter2() → (core::int*) →* core::int* {
+    self::enableRead = false;
+    return #C2;
+  }
+  get getter3() → (core::int*, core::int*) →* core::int* {
+    self::enableRead = false;
+    return #C3;
+  }
+  get getter4() → (core::int*, [core::int*]) →* core::int* {
+    self::enableRead = false;
+    return #C4;
+  }
+  get getter5() → ([core::int*, core::int*]) →* core::int* {
+    self::enableRead = false;
+    return #C5;
+  }
+  get getter6() → (core::int*, {b: core::int*}) →* core::int* {
+    self::enableRead = false;
+    return #C6;
+  }
+  get getter7() → ({a: core::int*, b: core::int*}) →* core::int* {
+    self::enableRead = false;
+    return #C7;
+  }
+}
+static field core::bool* enableRead = true;
+static method read(core::int* value) → core::int*
+  return self::enableRead ?{core::int*} value : 1.{core::int::unary-}(){() →* core::int*};
+static method method1() → core::int*
+  return 0;
+static method method2(core::int* a) → core::int*
+  return a.{core::int::unary-}(){() →* core::int*};
+static method method3(core::int* a, core::int* b) → core::int*
+  return a.{core::num::-}(b){(core::num*) →* core::int*};
+static method method4(core::int* a, [core::int* b = #C8]) → core::int*
+  return a.{core::num::-}(b){(core::num*) →* core::int*};
+static method method5([core::int* a = #C8, core::int* b = #C8]) → core::int*
+  return a.{core::num::-}(b){(core::num*) →* core::int*};
+static method method6(core::int* a, {core::int* b = #C8}) → core::int*
+  return a.{core::num::-}(b){(core::num*) →* core::int*};
+static method method7({core::int* a = #C8, core::int* b = #C8}) → core::int*
+  return a.{core::num::-}(b){(core::num*) →* core::int*};
+static method main() → dynamic {
+  self::callField(new self::Class::•());
+  self::callGetter(new self::Class::•());
+  self::callField(new self::Subclass::•());
+  self::callGetter(new self::Subclass::•());
+}
+static method callField(self::Class* c) → dynamic {
+  self::expect(0, c.{self::Class::field1a}{core::Function*}());
+  self::expect(0, c.{self::Class::field1b}{() →* core::int*}(){() →* core::int*});
+  self::expect(42.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t1 = c in let final core::int* #t2 = self::read(42) in #t1.{self::Class::field2}{(core::int*) →* core::int*}(#t2){(core::int*) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t3 = c in let final core::int* #t4 = self::read(12) in let final core::int* #t5 = self::read(23) in #t3.{self::Class::field3}{(core::int*, core::int*) →* core::int*}(#t4, #t5){(core::int*, core::int*) →* core::int*});
+  self::expect(12, let final self::Class* #t6 = c in let final core::int* #t7 = self::read(12) in #t6.{self::Class::field4}{(core::int*, [core::int*]) →* core::int*}(#t7){(core::int*, [core::int*]) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t8 = c in let final core::int* #t9 = self::read(12) in let final core::int* #t10 = self::read(23) in #t8.{self::Class::field4}{(core::int*, [core::int*]) →* core::int*}(#t9, #t10){(core::int*, [core::int*]) →* core::int*});
+  self::expect(0, c.{self::Class::field5}{([core::int*, core::int*]) →* core::int*}(){([core::int*, core::int*]) →* core::int*});
+  self::expect(12, let final self::Class* #t11 = c in let final core::int* #t12 = self::read(12) in #t11.{self::Class::field5}{([core::int*, core::int*]) →* core::int*}(#t12){([core::int*, core::int*]) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t13 = c in let final core::int* #t14 = self::read(12) in let final core::int* #t15 = self::read(23) in #t13.{self::Class::field5}{([core::int*, core::int*]) →* core::int*}(#t14, #t15){([core::int*, core::int*]) →* core::int*});
+  self::expect(12, let final self::Class* #t16 = c in let final core::int* #t17 = self::read(12) in #t16.{self::Class::field6}{(core::int*, {b: core::int*}) →* core::int*}(#t17){(core::int*, {b: core::int*}) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t18 = c in let final core::int* #t19 = self::read(12) in let final core::int* #t20 = self::read(23) in #t18.{self::Class::field6}{(core::int*, {b: core::int*}) →* core::int*}(#t19, b: #t20){(core::int*, {b: core::int*}) →* core::int*});
+  self::expect(0, c.{self::Class::field7}{({a: core::int*, b: core::int*}) →* core::int*}(){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(12, let final self::Class* #t21 = c in let final core::int* #t22 = self::read(12) in #t21.{self::Class::field7}{({a: core::int*, b: core::int*}) →* core::int*}(a: #t22){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(23.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t23 = c in let final core::int* #t24 = self::read(23) in #t23.{self::Class::field7}{({a: core::int*, b: core::int*}) →* core::int*}(b: #t24){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t25 = c in let final core::int* #t26 = self::read(12) in let final core::int* #t27 = self::read(23) in #t25.{self::Class::field7}{({a: core::int*, b: core::int*}) →* core::int*}(a: #t26, b: #t27){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t28 = c in let final core::int* #t29 = self::read(23) in let final core::int* #t30 = self::read(12) in #t28.{self::Class::field7}{({a: core::int*, b: core::int*}) →* core::int*}(b: #t29, a: #t30){({a: core::int*, b: core::int*}) →* core::int*});
+}
+static method callGetter(self::Class* c) → dynamic {
+  self::expect(0, c.{self::Class::getter1a}{core::Function*}());
+  self::expect(0, c.{self::Class::getter1b}{() →* core::int*}(){() →* core::int*});
+  self::expect(42.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t31 = c in let final core::int* #t32 = self::read(42) in #t31.{self::Class::getter2}{(core::int*) →* core::int*}(#t32){(core::int*) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t33 = c in let final core::int* #t34 = self::read(12) in let final core::int* #t35 = self::read(23) in #t33.{self::Class::getter3}{(core::int*, core::int*) →* core::int*}(#t34, #t35){(core::int*, core::int*) →* core::int*});
+  self::expect(12, let final self::Class* #t36 = c in let final core::int* #t37 = self::read(12) in #t36.{self::Class::getter4}{(core::int*, [core::int*]) →* core::int*}(#t37){(core::int*, [core::int*]) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t38 = c in let final core::int* #t39 = self::read(12) in let final core::int* #t40 = self::read(23) in #t38.{self::Class::getter4}{(core::int*, [core::int*]) →* core::int*}(#t39, #t40){(core::int*, [core::int*]) →* core::int*});
+  self::expect(0, c.{self::Class::getter5}{([core::int*, core::int*]) →* core::int*}(){([core::int*, core::int*]) →* core::int*});
+  self::expect(12, let final self::Class* #t41 = c in let final core::int* #t42 = self::read(12) in #t41.{self::Class::getter5}{([core::int*, core::int*]) →* core::int*}(#t42){([core::int*, core::int*]) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t43 = c in let final core::int* #t44 = self::read(12) in let final core::int* #t45 = self::read(23) in #t43.{self::Class::getter5}{([core::int*, core::int*]) →* core::int*}(#t44, #t45){([core::int*, core::int*]) →* core::int*});
+  self::expect(12, let final self::Class* #t46 = c in let final core::int* #t47 = self::read(12) in #t46.{self::Class::getter6}{(core::int*, {b: core::int*}) →* core::int*}(#t47){(core::int*, {b: core::int*}) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t48 = c in let final core::int* #t49 = self::read(12) in let final core::int* #t50 = self::read(23) in #t48.{self::Class::getter6}{(core::int*, {b: core::int*}) →* core::int*}(#t49, b: #t50){(core::int*, {b: core::int*}) →* core::int*});
+  self::expect(0, c.{self::Class::getter7}{({a: core::int*, b: core::int*}) →* core::int*}(){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(12, let final self::Class* #t51 = c in let final core::int* #t52 = self::read(12) in #t51.{self::Class::getter7}{({a: core::int*, b: core::int*}) →* core::int*}(a: #t52){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(23.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t53 = c in let final core::int* #t54 = self::read(23) in #t53.{self::Class::getter7}{({a: core::int*, b: core::int*}) →* core::int*}(b: #t54){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t55 = c in let final core::int* #t56 = self::read(12) in let final core::int* #t57 = self::read(23) in #t55.{self::Class::getter7}{({a: core::int*, b: core::int*}) →* core::int*}(a: #t56, b: #t57){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t58 = c in let final core::int* #t59 = self::read(23) in let final core::int* #t60 = self::read(12) in #t58.{self::Class::getter7}{({a: core::int*, b: core::int*}) →* core::int*}(b: #t59, a: #t60){({a: core::int*, b: core::int*}) →* core::int*});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  self::enableRead = true;
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, ${actual}";
+}
+
+constants  {
+  #C1 = static-tearoff self::method1
+  #C2 = static-tearoff self::method2
+  #C3 = static-tearoff self::method3
+  #C4 = static-tearoff self::method4
+  #C5 = static-tearoff self::method5
+  #C6 = static-tearoff self::method6
+  #C7 = static-tearoff self::method7
+  #C8 = 0
+}
diff --git a/pkg/front_end/testcases/general/getter_vs_setter_type.dart.weak.modular.expect b/pkg/front_end/testcases/general/getter_vs_setter_type.dart.weak.modular.expect
new file mode 100644
index 0000000..e38d7f0
--- /dev/null
+++ b/pkg/front_end/testcases/general/getter_vs_setter_type.dart.weak.modular.expect
@@ -0,0 +1,423 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:15:14: Error: The type 'String' of the getter 'A.property3' is not assignable to the type 'int' of the setter 'A.property3'.
+//   String get property3; // error
+//              ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:16:12: Context: This is the declaration of the setter 'A.property3'.
+//   void set property3(int i);
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:33:18: Error: The type 'num' of the getter 'A.property9' is not assignable to the type 'String' of the setter 'A.property9'.
+//   static num get property9 => 0; // error
+//                  ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:34:19: Context: This is the declaration of the setter 'A.property9'.
+//   static void set property9(String value) {}
+//                   ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:56:12: Error: The type 'int' of the inherited getter 'B1.property2' is not assignable to the type 'String' of the setter 'B2.property2'.
+//   void set property2(String i); // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:40:11: Context: This is the declaration of the getter 'B1.property2'.
+//   int get property2;
+//           ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:58:12: Error: The type 'String' of the inherited getter 'B1.property3' is not assignable to the type 'int' of the setter 'B2.property3'.
+//   void set property3(int i); // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:42:14: Context: This is the declaration of the getter 'B1.property3'.
+//   String get property3;
+//              ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:62:12: Error: The type 'int' of the inherited field 'B1.property5' is not assignable to the type 'String' of the setter 'B2.property5'.
+//   void set property5(String i); // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:46:13: Context: This is the declaration of the field 'B1.property5'.
+//   final int property5;
+//             ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:64:12: Error: The type 'String' of the inherited field 'B1.property6' is not assignable to the type 'int' of the setter 'B2.property6'.
+//   void set property6(int i); // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:48:16: Context: This is the declaration of the field 'B1.property6'.
+//   final String property6;
+//                ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:84:11: Error: The type 'int' of the getter 'C2.property2' is not assignable to the type 'String' of the inherited setter 'C1.property2'.
+//   int get property2; // error
+//           ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:70:12: Context: This is the declaration of the setter 'C1.property2'.
+//   void set property2(String i);
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:86:14: Error: The type 'String' of the getter 'C2.property3' is not assignable to the type 'int' of the inherited setter 'C1.property3'.
+//   String get property3; // error
+//              ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:72:12: Context: This is the declaration of the setter 'C1.property3'.
+//   void set property3(int i);
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:92:11: Error: The type 'int' of the getter 'C2.property5' is not assignable to the type 'String' of the inherited setter 'C1.property5'.
+//   int get property5; // error
+//           ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:76:10: Context: This is the declaration of the setter 'C1.property5'.
+//   String property5;
+//          ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:96:14: Error: The type 'String' of the getter 'C2.property6' is not assignable to the type 'int' of the inherited setter 'C1.property6'.
+//   String get property6; // error
+//              ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:78:7: Context: This is the declaration of the setter 'C1.property6'.
+//   int property6;
+//       ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:92:11: Error: The return type of the method 'C2.property5' is 'int', which does not match the return type, 'String', of the overridden method, 'C1.property5'.
+// Change to a subtype of 'String'.
+//   int get property5; // error
+//           ^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:76:10: Context: This is the overridden method ('property5').
+//   String property5;
+//          ^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:96:14: Error: The return type of the method 'C2.property6' is 'String', which does not match the return type, 'int', of the overridden method, 'C1.property6'.
+// Change to a subtype of 'int'.
+//   String get property6; // error
+//              ^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:78:7: Context: This is the overridden method ('property6').
+//   int property6;
+//       ^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:115:16: Error: The type 'int' of the inherited getter 'D1.property2' is not assignable to the type 'String' of the inherited setter 'D2.property2'.
+// abstract class D3 implements D1, D2 /* error on property2 and property3 */ {}
+//                ^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:102:11: Context: This is the declaration of the getter 'D1.property2'.
+//   int get property2;
+//           ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:110:12: Context: This is the declaration of the setter 'D2.property2'.
+//   void set property2(String i);
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:115:16: Error: The type 'String' of the inherited getter 'D1.property3' is not assignable to the type 'int' of the inherited setter 'D2.property3'.
+// abstract class D3 implements D1, D2 /* error on property2 and property3 */ {}
+//                ^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:104:14: Context: This is the declaration of the getter 'D1.property3'.
+//   String get property3;
+//              ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:112:12: Context: This is the declaration of the setter 'D2.property3'.
+//   void set property3(int i);
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:117:16: Error: The type 'int' of the inherited getter 'D1.property2' is not assignable to the type 'String' of the inherited setter 'D2.property2'.
+// abstract class D4
+//                ^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:102:11: Context: This is the declaration of the getter 'D1.property2'.
+//   int get property2;
+//           ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:110:12: Context: This is the declaration of the setter 'D2.property2'.
+//   void set property2(String i);
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:117:16: Error: The type 'String' of the inherited getter 'D1.property3' is not assignable to the type 'int' of the inherited setter 'D2.property3'.
+// abstract class D4
+//                ^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:104:14: Context: This is the declaration of the getter 'D1.property3'.
+//   String get property3;
+//              ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:112:12: Context: This is the declaration of the setter 'D2.property3'.
+//   void set property3(int i);
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:130:14: Error: The type 'String' of the getter 'property3' is not assignable to the type 'int' of the setter 'property3'.
+//   String get property3 => ''; // error
+//              ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:131:12: Context: This is the declaration of the setter 'property3'.
+//   void set property3(int i) {}
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:142:14: Error: The type 'String' of the getter 'property6' is not assignable to the type 'S' of the setter 'property6'.
+//   String get property6 => ''; // error
+//              ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:143:12: Context: This is the declaration of the setter 'property6'.
+//   void set property6(S i) {}
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:154:18: Error: The type 'num' of the getter 'property9' is not assignable to the type 'String' of the setter 'property9'.
+//   static num get property9 => 0; // error
+//                  ^^^^^^^^^
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:155:19: Context: This is the declaration of the setter 'property9'.
+//   static void set property9(String value) {}
+//                   ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:133:22: Error: A value of type 'int' can't be assigned to a variable of type 'S'.
+//   S get property4 => 0; // ok
+//                      ^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:136:23: Error: A value of type 'int' can't be assigned to a variable of type 'S'.
+//   S get property5a => 0; // ok
+//                       ^
+//
+// pkg/front_end/testcases/general/getter_vs_setter_type.dart:139:23: Error: A value of type 'int' can't be assigned to a variable of type 'T'.
+//   T get property5b => 0; // ok
+//                       ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  field core::int* property4 = null;
+  field core::int* property5 = null;
+  covariant-by-declaration field core::String* property6 = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract get property1() → core::int*;
+  abstract set property1(core::int* i) → void;
+  abstract get property2a() → core::num*;
+  abstract set property2a(core::int* i) → void;
+  abstract get property2b() → core::int*;
+  abstract set property2b(core::num* i) → void;
+  abstract get property3() → core::String*;
+  abstract set property3(core::int* i) → void;
+  static get property7() → core::int*
+    return 0;
+  static set property7(core::int* value) → void {}
+  static get property8a() → core::int*
+    return 0;
+  static set property8a(core::num* value) → void {}
+  static get property8b() → core::num*
+    return 0;
+  static set property8b(core::int* value) → void {}
+  static get property9() → core::num*
+    return 0;
+  static set property9(core::String* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B1 extends core::Object {
+  final field core::int* property4;
+  final field core::int* property5;
+  final field core::String* property6;
+  constructor •(core::int* property4, core::int* property5, core::String* property6) → self::B1*
+    : self::B1::property4 = property4, self::B1::property5 = property5, self::B1::property6 = property6, super core::Object::•()
+    ;
+  abstract get property1() → core::int*;
+  abstract get property2() → core::int*;
+  abstract get property3() → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B2 extends core::Object implements self::B1 {
+  synthetic constructor •() → self::B2*
+    : super core::Object::•()
+    ;
+  abstract set property1(core::int* i) → void;
+  abstract set property2(core::String* i) → void;
+  abstract set property3(core::int* i) → void;
+  abstract set property4(core::int* i) → void;
+  abstract set property5(core::String* i) → void;
+  abstract set property6(core::int* i) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C1 extends core::Object {
+  field core::int* property4 = null;
+  field core::String* property5 = null;
+  field core::int* property6 = null;
+  synthetic constructor •() → self::C1*
+    : super core::Object::•()
+    ;
+  abstract set property1(core::int* i) → void;
+  abstract set property2(core::String* i) → void;
+  abstract set property3(core::int* i) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C2 extends core::Object implements self::C1 {
+  synthetic constructor •() → self::C2*
+    : super core::Object::•()
+    ;
+  abstract get property1() → core::int*;
+  abstract get property2() → core::int*;
+  abstract get property3() → core::String*;
+  abstract get property4() → core::int*;
+  abstract get property5() → core::int*;
+  abstract get property6() → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D1 extends core::Object {
+  synthetic constructor •() → self::D1*
+    : super core::Object::•()
+    ;
+  abstract get property1() → core::int*;
+  abstract get property2() → core::int*;
+  abstract get property3() → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D2 extends core::Object {
+  synthetic constructor •() → self::D2*
+    : super core::Object::•()
+    ;
+  abstract set property1(core::int* i) → void;
+  abstract set property2(core::String* i) → void;
+  abstract set property3(core::int* i) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D3 extends core::Object implements self::D1, self::D2 {
+  synthetic constructor •() → self::D3*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D4 extends core::Object implements self::D3 {
+  synthetic constructor •() → self::D4*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension<T extends core::num*, S extends T* = core::num*> on core::int* {
+  get property1 = self::Extension|get#property1;
+  get property2a = self::Extension|get#property2a;
+  get property2b = self::Extension|get#property2b;
+  get property3 = self::Extension|get#property3;
+  get property4 = self::Extension|get#property4;
+  get property5a = self::Extension|get#property5a;
+  get property5b = self::Extension|get#property5b;
+  get property6 = self::Extension|get#property6;
+  static get property7 = get self::Extension|property7;
+  static get property8a = get self::Extension|property8a;
+  static get property8b = get self::Extension|property8b;
+  static get property9 = get self::Extension|property9;
+  set property1 = self::Extension|set#property1;
+  set property2a = self::Extension|set#property2a;
+  set property2b = self::Extension|set#property2b;
+  set property3 = self::Extension|set#property3;
+  set property4 = self::Extension|set#property4;
+  set property5a = self::Extension|set#property5a;
+  set property5b = self::Extension|set#property5b;
+  set property6 = self::Extension|set#property6;
+  static set property7 = set self::Extension|property7;
+  static set property8a = set self::Extension|property8a;
+  static set property8b = set self::Extension|property8b;
+  static set property9 = set self::Extension|property9;
+}
+static method Extension|get#property1<T extends core::num*, S extends self::Extension|get#property1::T* = core::num*>(lowered final core::int* #this) → core::int*
+  return 0;
+static method Extension|set#property1<T extends core::num*, S extends self::Extension|set#property1::T* = core::num*>(lowered final core::int* #this, core::int* i) → void {}
+static method Extension|get#property2a<T extends core::num*, S extends self::Extension|get#property2a::T* = core::num*>(lowered final core::int* #this) → core::num*
+  return 0;
+static method Extension|set#property2a<T extends core::num*, S extends self::Extension|set#property2a::T* = core::num*>(lowered final core::int* #this, core::int* i) → void {}
+static method Extension|get#property2b<T extends core::num*, S extends self::Extension|get#property2b::T* = core::num*>(lowered final core::int* #this) → core::int*
+  return 0;
+static method Extension|set#property2b<T extends core::num*, S extends self::Extension|set#property2b::T* = core::num*>(lowered final core::int* #this, core::num* i) → void {}
+static method Extension|get#property3<T extends core::num*, S extends self::Extension|get#property3::T* = core::num*>(lowered final core::int* #this) → core::String*
+  return "";
+static method Extension|set#property3<T extends core::num*, S extends self::Extension|set#property3::T* = core::num*>(lowered final core::int* #this, core::int* i) → void {}
+static method Extension|get#property4<T extends core::num*, S extends self::Extension|get#property4::T* = core::num*>(lowered final core::int* #this) → self::Extension|get#property4::S*
+  return invalid-expression "pkg/front_end/testcases/general/getter_vs_setter_type.dart:133:22: Error: A value of type 'int' can't be assigned to a variable of type 'S'.
+  S get property4 => 0; // ok
+                     ^" in 0 as{TypeError} Never;
+static method Extension|set#property4<T extends core::num*, S extends self::Extension|set#property4::T* = core::num*>(lowered final core::int* #this, self::Extension|set#property4::S* i) → void {}
+static method Extension|get#property5a<T extends core::num*, S extends self::Extension|get#property5a::T* = core::num*>(lowered final core::int* #this) → self::Extension|get#property5a::S*
+  return invalid-expression "pkg/front_end/testcases/general/getter_vs_setter_type.dart:136:23: Error: A value of type 'int' can't be assigned to a variable of type 'S'.
+  S get property5a => 0; // ok
+                      ^" in 0 as{TypeError} Never;
+static method Extension|set#property5a<T extends core::num*, S extends self::Extension|set#property5a::T* = core::num*>(lowered final core::int* #this, self::Extension|set#property5a::T* i) → void {}
+static method Extension|get#property5b<T extends core::num*, S extends self::Extension|get#property5b::T* = core::num*>(lowered final core::int* #this) → self::Extension|get#property5b::T*
+  return invalid-expression "pkg/front_end/testcases/general/getter_vs_setter_type.dart:139:23: Error: A value of type 'int' can't be assigned to a variable of type 'T'.
+  T get property5b => 0; // ok
+                      ^" in 0 as{TypeError} Never;
+static method Extension|set#property5b<T extends core::num*, S extends self::Extension|set#property5b::T* = core::num*>(lowered final core::int* #this, self::Extension|set#property5b::S* i) → void {}
+static method Extension|get#property6<T extends core::num*, S extends self::Extension|get#property6::T* = core::num*>(lowered final core::int* #this) → core::String*
+  return "";
+static method Extension|set#property6<T extends core::num*, S extends self::Extension|set#property6::T* = core::num*>(lowered final core::int* #this, self::Extension|set#property6::S* i) → void {}
+static get Extension|property7() → core::int*
+  return 0;
+static set Extension|property7(core::int* value) → void {}
+static get Extension|property8a() → core::int*
+  return 0;
+static set Extension|property8a(core::num* value) → void {}
+static get Extension|property8b() → core::num*
+  return 0;
+static set Extension|property8b(core::int* value) → void {}
+static get Extension|property9() → core::num*
+  return 0;
+static set Extension|property9(core::String* value) → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/having_part_with_part_and_annotation.dart.weak.modular.expect b/pkg/front_end/testcases/general/having_part_with_part_and_annotation.dart.weak.modular.expect
new file mode 100644
index 0000000..5744ee3
--- /dev/null
+++ b/pkg/front_end/testcases/general/having_part_with_part_and_annotation.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/having_part_with_part_and_annotation_lib1.dart:10:6: Error: A file that's a part of a library can't have parts itself.
+// Try moving the 'part' declaration to the containing library.
+// part 'having_part_with_part_and_annotation_lib2.dart';
+//      ^
+// pkg/front_end/testcases/general/having_part_with_part_and_annotation.dart: Context: This is the containing library.
+//
+import self as self;
+import "dart:core" as core;
+
+@#C1
+part having_part_with_part_and_annotation_lib1.dart;
+static const field core::int* Foo = #C1;
+static const field core::int* Bar = #C2 /* from org-dartlang-testcase:///having_part_with_part_and_annotation_lib1.dart */;
+static method fromMain() → void {}
+static method main() → dynamic {}
+static method /* from org-dartlang-testcase:///having_part_with_part_and_annotation_lib1.dart */ fromLib1() → void {}
+
+constants  {
+  #C1 = 42
+  #C2 = 43
+}
diff --git a/pkg/front_end/testcases/general/having_part_with_parts_and_annotation.dart.weak.modular.expect b/pkg/front_end/testcases/general/having_part_with_parts_and_annotation.dart.weak.modular.expect
new file mode 100644
index 0000000..9054021
--- /dev/null
+++ b/pkg/front_end/testcases/general/having_part_with_parts_and_annotation.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/having_part_with_parts_and_annotation.dart:6:6: Error: The language version override has to be the same in the library and its part(s).
+// part 'having_part_with_parts_and_annotation_lib1.dart';
+//      ^
+// pkg/front_end/testcases/general/having_part_with_parts_and_annotation.dart:4:1: Context: This is language version annotation in the library.
+// // @dart=2.9
+// ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/having_part_with_parts_and_annotation_lib1.dart:4:6: Error: A file that's a part of a library can't have parts itself.
+// Try moving the 'part' declaration to the containing library.
+// part 'having_part_with_parts_and_annotation_lib2.dart';
+//      ^
+// pkg/front_end/testcases/general/having_part_with_parts_and_annotation.dart: Context: This is the containing library.
+//
+// pkg/front_end/testcases/general/having_part_with_parts_and_annotation_lib1.dart:6:6: Error: A file that's a part of a library can't have parts itself.
+// Try moving the 'part' declaration to the containing library.
+// part 'having_part_with_parts_and_annotation_lib2.dart';
+//      ^
+// pkg/front_end/testcases/general/having_part_with_parts_and_annotation.dart: Context: This is the containing library.
+//
+import self as self;
+import "dart:core" as core;
+
+@#C1
+part having_part_with_parts_and_annotation_lib1.dart;
+static const field core::int* Foo = #C1;
+static const field core::int* Bar = #C2 /*isNonNullableByDefault, from org-dartlang-testcase:///having_part_with_parts_and_annotation_lib1.dart */;
+static const field core::int* Baz = #C3 /*isNonNullableByDefault, from org-dartlang-testcase:///having_part_with_parts_and_annotation_lib1.dart */;
+static method fromMain() → void {}
+static method main() → dynamic {}
+static method /*isNonNullableByDefault, from org-dartlang-testcase:///having_part_with_parts_and_annotation_lib1.dart */ fromLib1() → void {}
+
+constants  {
+  #C1 = 42
+  #C2 = 43
+  #C3 = 44
+}
diff --git a/pkg/front_end/testcases/general/hello.dart.weak.modular.expect b/pkg/front_end/testcases/general/hello.dart.weak.modular.expect
new file mode 100644
index 0000000..fea7b39
--- /dev/null
+++ b/pkg/front_end/testcases/general/hello.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::print("Hello, World!");
+}
diff --git a/pkg/front_end/testcases/general/hierarchy.dart.weak.modular.expect b/pkg/front_end/testcases/general/hierarchy.dart.weak.modular.expect
new file mode 100644
index 0000000..3c3d062
--- /dev/null
+++ b/pkg/front_end/testcases/general/hierarchy.dart.weak.modular.expect
@@ -0,0 +1,325 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/hierarchy.dart:24:7: Error: The non-abstract class 'A6' is missing implementations for these members:
+//  - A1.extendedInterfaceMember
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class A6 extends A1 implements A1 {}
+//       ^^
+// pkg/front_end/testcases/general/hierarchy.dart:7:8: Context: 'A1.extendedInterfaceMember' is defined here.
+//   void extendedInterfaceMember();
+//        ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/hierarchy.dart:41:7: Error: The non-abstract class 'B5' is missing implementations for these members:
+//  - B1.twiceInterfaceMember
+//  - B2.twiceInterfaceMember
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class B5 extends B4 {}
+//       ^^
+// pkg/front_end/testcases/general/hierarchy.dart:27:8: Context: 'B1.twiceInterfaceMember' is defined here.
+//   void twiceInterfaceMember() {}
+//        ^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/hierarchy.dart:32:8: Context: 'B2.twiceInterfaceMember' is defined here.
+//   void twiceInterfaceMember() {}
+//        ^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/hierarchy.dart:43:7: Error: The non-abstract class 'B6' is missing implementations for these members:
+//  - B1.twiceInterfaceMember
+//  - B2.twiceInterfaceMember
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class B6 extends B3 implements B1, B2 {}
+//       ^^
+// pkg/front_end/testcases/general/hierarchy.dart:27:8: Context: 'B1.twiceInterfaceMember' is defined here.
+//   void twiceInterfaceMember() {}
+//        ^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/hierarchy.dart:32:8: Context: 'B2.twiceInterfaceMember' is defined here.
+//   void twiceInterfaceMember() {}
+//        ^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/hierarchy.dart:57:7: Error: The non-abstract class 'C4' is missing implementations for these members:
+//  - C1.mixedInAndImplementedInterfaceMember
+//  - C2.mixedInAndImplementedInterfaceMember
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class C4 extends C3 {}
+//       ^^
+// pkg/front_end/testcases/general/hierarchy.dart:47:8: Context: 'C1.mixedInAndImplementedInterfaceMember' is defined here.
+//   void mixedInAndImplementedInterfaceMember();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/hierarchy.dart:52:8: Context: 'C2.mixedInAndImplementedInterfaceMember' is defined here.
+//   void mixedInAndImplementedInterfaceMember() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/hierarchy.dart:59:7: Error: The non-abstract class 'C5' is missing implementations for these members:
+//  - C1.mixedInAndImplementedInterfaceMember
+//  - C2.mixedInAndImplementedInterfaceMember
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class C5 with C1 implements C2 {}
+//       ^^
+// pkg/front_end/testcases/general/hierarchy.dart:47:8: Context: 'C1.mixedInAndImplementedInterfaceMember' is defined here.
+//   void mixedInAndImplementedInterfaceMember();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/hierarchy.dart:52:8: Context: 'C2.mixedInAndImplementedInterfaceMember' is defined here.
+//   void mixedInAndImplementedInterfaceMember() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/hierarchy.dart:24:7: Error: 'A1' can't be used in both 'extends' and 'implements' clauses.
+// Try removing one of the occurrences.
+// class A6 extends A1 implements A1 {}
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A1 extends core::Object {
+  synthetic constructor •() → self::A1*
+    : super core::Object::•()
+    ;
+  method extendedClassMember() → void {}
+  abstract method extendedInterfaceMember() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class A2 extends core::Object {
+  synthetic constructor •() → self::A2*
+    : super core::Object::•()
+    ;
+  method mixedInClassMember() → void {}
+  abstract method mixedInInterfaceMember() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _A3&A1&A2 = self::A1 with self::A2 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A3&A1&A2*
+    : super self::A1::•()
+    ;
+  mixin-super-stub method mixedInClassMember() → void
+    return super.{self::A2::mixedInClassMember}();
+  abstract mixin-stub method mixedInInterfaceMember() → void; -> self::A2::mixedInInterfaceMember
+}
+abstract class A3 extends self::_A3&A1&A2 {
+  synthetic constructor •() → self::A3*
+    : super self::_A3&A1&A2::•()
+    ;
+  method declaredClassMember() → void {}
+  abstract method declaredInterfaceMember() → void;
+}
+abstract class A4 = self::A1 with self::A2 {
+  synthetic constructor •() → self::A4*
+    : super self::A1::•()
+    ;
+  mixin-super-stub method mixedInClassMember() → void
+    return super.{self::A2::mixedInClassMember}();
+  abstract mixin-stub method mixedInInterfaceMember() → void; -> self::A2::mixedInInterfaceMember
+}
+abstract class A5 extends core::Object implements self::A1 {
+  synthetic constructor •() → self::A5*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A6 extends self::A1 implements self::A1 {
+  synthetic constructor •() → self::A6*
+    : super self::A1::•()
+    ;
+}
+abstract class B1 extends core::Object {
+  synthetic constructor •() → self::B1*
+    : super core::Object::•()
+    ;
+  method twiceInterfaceMember() → void {}
+  method extendedAndImplementedMember() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B2 extends core::Object {
+  synthetic constructor •() → self::B2*
+    : super core::Object::•()
+    ;
+  method twiceInterfaceMember() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B3 extends core::Object {
+  synthetic constructor •() → self::B3*
+    : super core::Object::•()
+    ;
+  method extendedAndImplementedMember() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B4 extends self::B3 implements self::B1, self::B2 {
+  synthetic constructor •() → self::B4*
+    : super self::B3::•()
+    ;
+}
+class B5 extends self::B4 {
+  synthetic constructor •() → self::B5*
+    : super self::B4::•()
+    ;
+}
+class B6 extends self::B3 implements self::B1, self::B2 {
+  synthetic constructor •() → self::B6*
+    : super self::B3::•()
+    ;
+}
+abstract class C1 extends core::Object {
+  synthetic constructor •() → self::C1*
+    : super core::Object::•()
+    ;
+  method mixedInAndImplementedClassMember() → void {}
+  abstract method mixedInAndImplementedInterfaceMember() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C2 extends core::Object {
+  synthetic constructor •() → self::C2*
+    : super core::Object::•()
+    ;
+  method mixedInAndImplementedClassMember() → void {}
+  method mixedInAndImplementedInterfaceMember() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C3&Object&C1 = core::Object with self::C1 /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C3&Object&C1*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method mixedInAndImplementedClassMember() → void
+    return super.{self::C1::mixedInAndImplementedClassMember}();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract mixin-stub method mixedInAndImplementedInterfaceMember() → void; -> self::C1::mixedInAndImplementedInterfaceMember
+}
+abstract class C3 extends self::_C3&Object&C1 implements self::C2 {
+  synthetic constructor •() → self::C3*
+    : super self::_C3&Object&C1::•()
+    ;
+}
+class C4 extends self::C3 {
+  synthetic constructor •() → self::C4*
+    : super self::C3::•()
+    ;
+}
+abstract class _C5&Object&C1 = core::Object with self::C1 /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C5&Object&C1*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method mixedInAndImplementedClassMember() → void
+    return super.{self::C1::mixedInAndImplementedClassMember}();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract mixin-stub method mixedInAndImplementedInterfaceMember() → void; -> self::C1::mixedInAndImplementedInterfaceMember
+}
+class C5 extends self::_C5&Object&C1 implements self::C2 {
+  synthetic constructor •() → self::C5*
+    : super self::_C5&Object&C1::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/identical_instantiated_function_tearoffs.dart.weak.modular.expect b/pkg/front_end/testcases/general/identical_instantiated_function_tearoffs.dart.weak.modular.expect
new file mode 100644
index 0000000..d1b803d
--- /dev/null
+++ b/pkg/front_end/testcases/general/identical_instantiated_function_tearoffs.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static field (core::int) → core::int implicitInstantiation = #C2;
+static const field (core::int) → core::int implicitConstInstantiation = #C2;
+static method id<T extends core::Object? = dynamic>(self::id::T% t) → self::id::T%
+  return t;
+static method create<T extends core::Object? = dynamic>() → (self::create::T%) → self::create::T%
+  return #C1<self::create::T%>;
+static method main() → dynamic {
+  self::expect(true, core::identical(self::implicitInstantiation, self::implicitInstantiation));
+  self::expect(true, core::identical(self::implicitInstantiation, #C2));
+  self::expect(false, core::identical(self::implicitInstantiation, self::create<core::int>()));
+  self::expect(true, core::identical(#C2, self::implicitInstantiation));
+  self::expect(true, core::identical(#C2, #C2));
+  self::expect(false, core::identical(#C2, self::create<core::int>()));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = static-tearoff self::id
+  #C2 = instantiation #C1 <core::int*>
+}
diff --git a/pkg/front_end/testcases/general/if_null_in_cascade.dart.weak.modular.expect b/pkg/front_end/testcases/general/if_null_in_cascade.dart.weak.modular.expect
new file mode 100644
index 0000000..9873ac0
--- /dev/null
+++ b/pkg/front_end/testcases/general/if_null_in_cascade.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  method method() → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::Class* a;
+  self::Class* b = new self::Class::•();
+  let final self::Class* #t1 = let final self::Class* #t2 = a in #t2 == null ?{self::Class*} b : #t2 in block {
+    #t1.{self::Class::method}(){() →* dynamic};
+  } =>#t1;
+}
diff --git a/pkg/front_end/testcases/general/if_null_in_list_literal.dart.weak.modular.expect b/pkg/front_end/testcases/general/if_null_in_list_literal.dart.weak.modular.expect
new file mode 100644
index 0000000..e781dcd
--- /dev/null
+++ b/pkg/front_end/testcases/general/if_null_in_list_literal.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::Object* a;
+  core::Object* b;
+  return <core::Object*>[let final core::Object* #t1 = a in #t1 == null ?{core::Object*} b : #t1];
+}
diff --git a/pkg/front_end/testcases/general/if_null_in_set_literal.dart.weak.modular.expect b/pkg/front_end/testcases/general/if_null_in_set_literal.dart.weak.modular.expect
new file mode 100644
index 0000000..cc17e25
--- /dev/null
+++ b/pkg/front_end/testcases/general/if_null_in_set_literal.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+static method main() → dynamic {
+  core::Object* a;
+  core::Object* b;
+  return block {
+    final core::Set<core::Object*>* #t1 = col::LinkedHashSet::•<core::Object*>();
+    #t1.{core::Set::add}{Invariant}(let final core::Object* #t2 = a in #t2 == null ?{core::Object*} b : #t2){(core::Object*) →* core::bool*};
+  } =>#t1;
+}
diff --git a/pkg/front_end/testcases/general/ignore_function.dart.weak.modular.expect b/pkg/front_end/testcases/general/ignore_function.dart.weak.modular.expect
new file mode 100644
index 0000000..004e6cc
--- /dev/null
+++ b/pkg/front_end/testcases/general/ignore_function.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/ignore_function.dart:18:7: Error: 'Function' is a built-in identifier, could not used as a class name.
+// class Function {
+//       ^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator ==(dynamic other) → core::bool*
+    return false;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::Function {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  operator ==(dynamic other) → core::bool*
+    return false;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Function extends core::Object {
+  synthetic constructor •() → self::Function*
+    : super core::Object::•()
+    ;
+  operator ==(core::Object* other) → core::bool*
+    return false;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/illegal_named_function_expression.dart.weak.modular.expect b/pkg/front_end/testcases/general/illegal_named_function_expression.dart.weak.modular.expect
new file mode 100644
index 0000000..96419b3
--- /dev/null
+++ b/pkg/front_end/testcases/general/illegal_named_function_expression.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/illegal_named_function_expression.dart:6:16: Error: A function expression can't have a name.
+//   var x = void f<T>(T t) {};
+//                ^
+//
+// pkg/front_end/testcases/general/illegal_named_function_expression.dart:8:14: Error: A function expression can't have a name.
+//   print(void g<T>(T t) {});
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  <T extends core::Object* = dynamic>(T*) →* Null x = let final <T extends core::Object* = dynamic>(T*) →* Null f = <T extends core::Object* = dynamic>(T* t) → Null {} in f;
+  core::print(x.{core::Object::runtimeType}{core::Type*});
+  core::print(let final <T extends core::Object* = dynamic>(T*) →* Null g = <T extends core::Object* = dynamic>(T* t) → Null {} in g);
+}
diff --git a/pkg/front_end/testcases/general/illegal_named_function_expression_scope.dart.weak.modular.expect b/pkg/front_end/testcases/general/illegal_named_function_expression_scope.dart.weak.modular.expect
new file mode 100644
index 0000000..63bcf5a
--- /dev/null
+++ b/pkg/front_end/testcases/general/illegal_named_function_expression_scope.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/illegal_named_function_expression_scope.dart:7:14: Error: A function expression can't have a name.
+//   print(void f() {});
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  function f() → void {}
+  core::print(let final () →* Null f = () → Null {} in f);
+}
diff --git a/pkg/front_end/testcases/general/implement_semi_stub.dart.weak.modular.expect b/pkg/front_end/testcases/general/implement_semi_stub.dart.weak.modular.expect
new file mode 100644
index 0000000..e8b7608
--- /dev/null
+++ b/pkg/front_end/testcases/general/implement_semi_stub.dart.weak.modular.expect
@@ -0,0 +1,222 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/implement_semi_stub.dart:52:23: Error: The parameter 'a' of the method 'Class1.method1' has type 'double', which does not match the corresponding type, 'int', in the overridden method, 'Class.method1'.
+// Change to a supertype of 'int', or, for a covariant parameter, a subtype.
+//   void method1(double a) {} // error
+//                       ^
+// pkg/front_end/testcases/general/implement_semi_stub.dart:39:8: Context: This is the overridden method ('method1').
+//   void method1(covariant int a);
+//        ^
+//
+// pkg/front_end/testcases/general/implement_semi_stub.dart:53:23: Error: The parameter 'b' of the method 'Class1.method2' has type 'double', which does not match the corresponding type, 'int', in the overridden method, 'Super.method2'.
+// Change to a supertype of 'int', or, for a covariant parameter, a subtype.
+//   void method2(double b) {} // error
+//                       ^
+// pkg/front_end/testcases/general/implement_semi_stub.dart:7:8: Context: This is the overridden method ('method2').
+//   void method2(int b) {}
+//        ^
+//
+// pkg/front_end/testcases/general/implement_semi_stub.dart:54:23: Error: The parameter 'a' of the method 'Class1.method3' has type 'double', which does not match the corresponding type, 'int', in the overridden method, 'Class.method3'.
+// Change to a supertype of 'int', or, for a covariant parameter, a subtype.
+//   void method3(double a, double b) {} // error
+//                       ^
+// pkg/front_end/testcases/general/implement_semi_stub.dart:41:8: Context: This is the overridden method ('method3').
+//   void method3(covariant int a, num b);
+//        ^
+//
+// pkg/front_end/testcases/general/implement_semi_stub.dart:54:33: Error: The parameter 'b' of the method 'Class1.method3' has type 'double', which does not match the corresponding type, 'int', in the overridden method, 'Super.method3'.
+// Change to a supertype of 'int', or, for a covariant parameter, a subtype.
+//   void method3(double a, double b) {} // error
+//                                 ^
+// pkg/front_end/testcases/general/implement_semi_stub.dart:8:8: Context: This is the overridden method ('method3').
+//   void method3(num a, int b) {}
+//        ^
+//
+// pkg/front_end/testcases/general/implement_semi_stub.dart:55:33: Error: The parameter 'a' of the method 'Class1.method4' has type 'double', which does not match the corresponding type, 'num', in the overridden method, 'Super.method4'.
+// Change to a supertype of 'num', or, for a covariant parameter, a subtype.
+//   void method4({required double a}) {} // error
+//                                 ^
+// pkg/front_end/testcases/general/implement_semi_stub.dart:9:8: Context: This is the overridden method ('method4').
+//   void method4({required num a}) {}
+//        ^
+//
+// pkg/front_end/testcases/general/implement_semi_stub.dart:56:33: Error: The parameter 'b' of the method 'Class1.method5' has type 'double', which does not match the corresponding type, 'int', in the overridden method, 'Super.method5'.
+// Change to a supertype of 'int', or, for a covariant parameter, a subtype.
+//   void method5({required double b}) {} // error
+//                                 ^
+// pkg/front_end/testcases/general/implement_semi_stub.dart:10:8: Context: This is the overridden method ('method5').
+//   void method5({required int b}) {}
+//        ^
+//
+// pkg/front_end/testcases/general/implement_semi_stub.dart:58:23: Error: The parameter 'a' of the method 'Class1.method7' has type 'Set<T>', which does not match the corresponding type, 'List<T>', in the overridden method, 'Class.method7'.
+//  - 'Set' is from 'dart:core'.
+//  - 'List' is from 'dart:core'.
+// Change to a supertype of 'List<T>', or, for a covariant parameter, a subtype.
+//   void method7(Set<T> a) {} // error
+//                       ^
+// pkg/front_end/testcases/general/implement_semi_stub.dart:42:8: Context: This is the overridden method ('method7').
+//   void method7(covariant List<T> a);
+//        ^
+//
+// pkg/front_end/testcases/general/implement_semi_stub.dart:59:23: Error: The parameter 'b' of the method 'Class1.method8' has type 'Set<T>', which does not match the corresponding type, 'List<T>', in the overridden method, 'Super.method8'.
+//  - 'Set' is from 'dart:core'.
+//  - 'List' is from 'dart:core'.
+// Change to a supertype of 'List<T>', or, for a covariant parameter, a subtype.
+//   void method8(Set<T> b) {} // error
+//                       ^
+// pkg/front_end/testcases/general/implement_semi_stub.dart:13:8: Context: This is the overridden method ('method8').
+//   void method8(List<T> b) {}
+//        ^
+//
+// pkg/front_end/testcases/general/implement_semi_stub.dart:60:23: Error: The parameter 'a' of the method 'Class1.method9' has type 'Set<T>', which does not match the corresponding type, 'List<T>', in the overridden method, 'Class.method9'.
+//  - 'Set' is from 'dart:core'.
+//  - 'List' is from 'dart:core'.
+// Change to a supertype of 'List<T>', or, for a covariant parameter, a subtype.
+//   void method9(Set<T> a, Set<T> b) {} // error
+//                       ^
+// pkg/front_end/testcases/general/implement_semi_stub.dart:44:8: Context: This is the overridden method ('method9').
+//   void method9(covariant List<T> a, Iterable<T> b);
+//        ^
+//
+// pkg/front_end/testcases/general/implement_semi_stub.dart:60:33: Error: The parameter 'b' of the method 'Class1.method9' has type 'Set<T>', which does not match the corresponding type, 'List<T>', in the overridden method, 'Super.method9'.
+//  - 'Set' is from 'dart:core'.
+//  - 'List' is from 'dart:core'.
+// Change to a supertype of 'List<T>', or, for a covariant parameter, a subtype.
+//   void method9(Set<T> a, Set<T> b) {} // error
+//                                 ^
+// pkg/front_end/testcases/general/implement_semi_stub.dart:14:8: Context: This is the overridden method ('method9').
+//   void method9(Iterable<T> a, List<T> b) {}
+//        ^
+//
+// pkg/front_end/testcases/general/implement_semi_stub.dart:61:34: Error: The parameter 'a' of the method 'Class1.method10' has type 'Set<T>', which does not match the corresponding type, 'Iterable<T>', in the overridden method, 'Super.method10'.
+//  - 'Set' is from 'dart:core'.
+//  - 'Iterable' is from 'dart:core'.
+// Change to a supertype of 'Iterable<T>', or, for a covariant parameter, a subtype.
+//   void method10({required Set<T> a}) {} // error
+//                                  ^
+// pkg/front_end/testcases/general/implement_semi_stub.dart:15:8: Context: This is the overridden method ('method10').
+//   void method10({required Iterable<T> a}) {}
+//        ^
+//
+// pkg/front_end/testcases/general/implement_semi_stub.dart:62:34: Error: The parameter 'b' of the method 'Class1.method11' has type 'Set<T>', which does not match the corresponding type, 'List<T>', in the overridden method, 'Super.method11'.
+//  - 'Set' is from 'dart:core'.
+//  - 'List' is from 'dart:core'.
+// Change to a supertype of 'List<T>', or, for a covariant parameter, a subtype.
+//   void method11({required Set<T> b}) {} // error
+//                                  ^
+// pkg/front_end/testcases/general/implement_semi_stub.dart:16:8: Context: This is the overridden method ('method11').
+//   void method11({required List<T> b}) {}
+//        ^
+//
+// pkg/front_end/testcases/general/implement_semi_stub.dart:64:27: Error: The parameter 'a' of the method 'Class1.setter1' has type 'double', which does not match the corresponding type, 'int', in the overridden method, 'Class.setter1'.
+// Change to a supertype of 'int', or, for a covariant parameter, a subtype.
+//   void set setter1(double a) {} // error
+//                           ^
+// pkg/front_end/testcases/general/implement_semi_stub.dart:45:12: Context: This is the overridden method ('setter1').
+//   void set setter1(covariant int a);
+//            ^
+//
+// pkg/front_end/testcases/general/implement_semi_stub.dart:66:27: Error: The parameter 'a' of the method 'Class1.setter3' has type 'Set<T>', which does not match the corresponding type, 'List<T>', in the overridden method, 'Class.setter3'.
+//  - 'Set' is from 'dart:core'.
+//  - 'List' is from 'dart:core'.
+// Change to a supertype of 'List<T>', or, for a covariant parameter, a subtype.
+//   void set setter3(Set<T> a) {} // error
+//                           ^
+// pkg/front_end/testcases/general/implement_semi_stub.dart:47:12: Context: This is the overridden method ('setter3').
+//   void set setter3(covariant List<T> a);
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Super<self::Super::T%>
+    : super core::Object::•()
+    ;
+  method method1(core::num a) → void {}
+  method method2(core::int b) → void {}
+  method method3(core::num a, core::int b) → void {}
+  method method4({required core::num a = #C1}) → void {}
+  method method5({required core::int b = #C1}) → void {}
+  method method7(covariant-by-class core::Iterable<self::Super::T%> a) → void {}
+  method method8(covariant-by-class core::List<self::Super::T%> b) → void {}
+  method method9(covariant-by-class core::Iterable<self::Super::T%> a, covariant-by-class core::List<self::Super::T%> b) → void {}
+  method method10({required covariant-by-class core::Iterable<self::Super::T%> a = #C1}) → void {}
+  method method11({required covariant-by-class core::List<self::Super::T%> b = #C1}) → void {}
+  set setter1(core::num a) → void {}
+  set setter3(covariant-by-class core::Iterable<self::Super::T%> a) → void {}
+}
+abstract class Interface<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Interface<self::Interface::T%>
+    : super core::Object::•()
+    ;
+  method method2(covariant-by-declaration core::num b) → void {}
+  method method3(core::num a, covariant-by-declaration core::num b) → void {}
+  method method5({required core::int b = #C1}) → void {}
+  method method8(covariant-by-declaration covariant-by-class core::Iterable<self::Interface::T%> b) → void {}
+  method method9(covariant-by-class core::Iterable<self::Interface::T%> a, covariant-by-declaration covariant-by-class core::Iterable<self::Interface::T%> b) → void {}
+  method method11({required covariant-by-class core::List<self::Interface::T%> b = #C1}) → void {}
+}
+class Class<T extends core::Object? = dynamic> extends self::Super<self::Class::T%> implements self::Interface<self::Class::T%> {
+  synthetic constructor •() → self::Class<self::Class::T%>
+    : super self::Super::•()
+    ;
+  forwarding-stub forwarding-semi-stub method /* signature-type: (core::int) → void */ method1(covariant-by-declaration core::num a) → void
+    return super.{self::Super::method1}(a);
+  forwarding-stub forwarding-semi-stub method /* signature-type: (core::num) → void */ method2(covariant-by-declaration core::int b) → void
+    return super.{self::Super::method2}(b);
+  forwarding-stub forwarding-semi-stub method /* signature-type: (core::int, core::num) → void */ method3(covariant-by-declaration core::num a, covariant-by-declaration core::int b) → void
+    return super.{self::Super::method3}(a, b);
+  forwarding-stub forwarding-semi-stub method /* signature-type: (core::List<self::Class::T%>) → void */ method7(covariant-by-declaration covariant-by-class core::Iterable<self::Class::T%> a) → void
+    return super.{self::Super::method7}(a);
+  forwarding-stub forwarding-semi-stub method /* signature-type: (core::Iterable<self::Class::T%>) → void */ method8(covariant-by-declaration covariant-by-class core::List<self::Class::T%> b) → void
+    return super.{self::Super::method8}(b);
+  forwarding-stub forwarding-semi-stub method /* signature-type: (core::List<self::Class::T%>, core::Iterable<self::Class::T%>) → void */ method9(covariant-by-declaration covariant-by-class core::Iterable<self::Class::T%> a, covariant-by-declaration covariant-by-class core::List<self::Class::T%> b) → void
+    return super.{self::Super::method9}(a, b);
+  forwarding-stub forwarding-semi-stub set /* signature-type: (core::int) → void */ setter1(covariant-by-declaration core::num a) → void
+    return super.{self::Super::setter1} = a;
+  forwarding-stub forwarding-semi-stub set /* signature-type: (core::List<self::Class::T%>) → void */ setter3(covariant-by-declaration covariant-by-class core::Iterable<self::Class::T%> a) → void
+    return super.{self::Super::setter3} = a;
+}
+class Class1<T extends core::Object? = dynamic> extends core::Object implements self::Class<self::Class1::T%> {
+  synthetic constructor •() → self::Class1<self::Class1::T%>
+    : super core::Object::•()
+    ;
+  method method1(covariant-by-declaration core::double a) → void {}
+  method method2(covariant-by-declaration core::double b) → void {}
+  method method3(covariant-by-declaration core::double a, covariant-by-declaration core::double b) → void {}
+  method method4({required core::double a = #C1}) → void {}
+  method method5({required core::double b = #C1}) → void {}
+  method method7(covariant-by-declaration covariant-by-class core::Set<self::Class1::T%> a) → void {}
+  method method8(covariant-by-declaration covariant-by-class core::Set<self::Class1::T%> b) → void {}
+  method method9(covariant-by-declaration covariant-by-class core::Set<self::Class1::T%> a, covariant-by-declaration covariant-by-class core::Set<self::Class1::T%> b) → void {}
+  method method10({required covariant-by-class core::Set<self::Class1::T%> a = #C1}) → void {}
+  method method11({required covariant-by-class core::Set<self::Class1::T%> b = #C1}) → void {}
+  set setter1(covariant-by-declaration core::double a) → void {}
+  set setter3(covariant-by-declaration covariant-by-class core::Set<self::Class1::T%> a) → void {}
+}
+abstract class Interface2<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Interface2<self::Interface2::T%>
+    : super core::Object::•()
+    ;
+  abstract method method1(core::int a) → void;
+  abstract method method2(core::int b) → void;
+  abstract method method3(core::int a, core::int b) → void;
+  abstract method method7(covariant-by-class core::List<self::Interface2::T%> a) → void;
+  abstract method method8(covariant-by-class core::List<self::Interface2::T%> b) → void;
+  abstract method method9(covariant-by-class core::List<self::Interface2::T%> a, covariant-by-class core::List<self::Interface2::T%> b) → void;
+  abstract set setter1(core::int a) → void;
+  abstract set setter3(covariant-by-class core::List<self::Interface2::T%> a) → void;
+}
+abstract class Class2<T extends core::Object? = dynamic> extends core::Object implements self::Class<self::Class2::T%>, self::Interface2<self::Class2::T%> {
+  synthetic constructor •() → self::Class2<self::Class2::T%>
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/implicit_const_with_static_fields.dart.weak.modular.expect b/pkg/front_end/testcases/general/implicit_const_with_static_fields.dart.weak.modular.expect
new file mode 100644
index 0000000..93d939a
--- /dev/null
+++ b/pkg/front_end/testcases/general/implicit_const_with_static_fields.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object /*hasConstConstructor*/  {
+  static const field core::int* constField = #C1;
+  const constructor •(dynamic x) → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field core::int* constTopLevelField = #C2;
+static method main() → dynamic {
+  new self::C::•(#C1);
+  new self::C::•(#C2);
+}
+
+constants  {
+  #C1 = 87
+  #C2 = 42
+}
diff --git a/pkg/front_end/testcases/general/implicit_constructor_02.dart.weak.modular.expect b/pkg/front_end/testcases/general/implicit_constructor_02.dart.weak.modular.expect
new file mode 100644
index 0000000..febd66a
--- /dev/null
+++ b/pkg/front_end/testcases/general/implicit_constructor_02.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::bool* v1;
+  field core::num* v2;
+  constructor •(core::bool* v1, core::num* v2) → self::A*
+    : self::A::v1 = v1, self::A::v2 = v2, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M1 extends core::Object {
+  field core::num* v2 = 1.{core::int::unary-}(){() →* core::int*};
+  synthetic constructor •() → self::M1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C = self::A with self::M1 {
+  synthetic constructor •(core::bool* v1, core::num* v2) → self::C*
+    : super self::A::•(v1, v2)
+    ;
+  mixin-super-stub get v2() → core::num*
+    return super.{self::M1::v2};
+  mixin-super-stub set v2(core::num* value) → void
+    return super.{self::M1::v2} = value;
+}
+static method main() → dynamic {
+  self::C* c = new self::C::•(true, 2);
+  self::expect(true, c.{self::A::v1}{core::bool*});
+  self::expect(1.{core::int::unary-}(){() →* core::int*}, c.{self::C::v2}{core::num*});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/general/implicit_covariance.dart.weak.modular.expect b/pkg/front_end/testcases/general/implicit_covariance.dart.weak.modular.expect
new file mode 100644
index 0000000..3fd3297
--- /dev/null
+++ b/pkg/front_end/testcases/general/implicit_covariance.dart.weak.modular.expect
@@ -0,0 +1,71 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract method foo(covariant-by-class self::A::T* x) → dynamic;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B<T extends core::Object* = dynamic> extends core::Object implements self::A<self::B::T*> {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method foo(core::num* x) → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _D&C&B<T extends core::num*> = self::C with self::B<self::_D&C&B::T*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_D&C&B<self::_D&C&B::T*>*
+    : super self::C::•()
+    ;
+  forwarding-stub method foo(covariant-by-class core::num* x) → dynamic
+    return super.{self::C::foo}(x);
+}
+class D<T extends core::num*> extends self::_D&C&B<self::D::T*> {
+  synthetic constructor •() → self::D<self::D::T*>*
+    : super self::_D&C&B::•()
+    ;
+}
+class E<T extends core::num*> = self::C with self::B<self::E::T*> {
+  synthetic constructor •() → self::E<self::E::T*>*
+    : super self::C::•()
+    ;
+  forwarding-stub method foo(covariant-by-class core::num* x) → dynamic
+    return super.{self::C::foo}(x);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/implicit_instantiation.dart.weak.modular.expect b/pkg/front_end/testcases/general/implicit_instantiation.dart.weak.modular.expect
new file mode 100644
index 0000000..b226b4e
--- /dev/null
+++ b/pkg/front_end/testcases/general/implicit_instantiation.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/implicit_instantiation.dart:18:25: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'int Function(int)'.
+//   int Function(int) f = alias;
+//                         ^
+//
+// pkg/front_end/testcases/general/implicit_instantiation.dart:20:7: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'int Function(int)'.
+//   g = alias;
+//       ^
+//
+// pkg/front_end/testcases/general/implicit_instantiation.dart:21:21: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'int Function(int)'.
+//   int Function(int) h = c;
+//                     ^
+//
+// pkg/front_end/testcases/general/implicit_instantiation.dart:22:3: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'int Function(int)'.
+//   g = c;
+//   ^
+//
+// pkg/front_end/testcases/general/implicit_instantiation.dart:23:10: Error: The argument type 'T Function<T>(T)' can't be assigned to the parameter type 'int Function(int)'.
+//   method(alias);
+//          ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  method call<T extends core::Object? = dynamic>(self::Class::call::T% t) → self::Class::call::T%
+    return t;
+}
+static field <T extends core::Object? = dynamic>(T%) → T% alias = #C1;
+static method id<T extends core::Object? = dynamic>(self::id::T% t) → self::id::T%
+  return t;
+static method method((core::int) → core::int f) → dynamic {}
+static method test() → dynamic {
+  self::Class c = new self::Class::•();
+  (core::int) → core::int f = invalid-expression "pkg/front_end/testcases/general/implicit_instantiation.dart:18:25: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'int Function(int)'.
+  int Function(int) f = alias;
+                        ^" in self::alias as{TypeError,ForNonNullableByDefault} (core::int) → core::int;
+  (core::int) → core::int g;
+  g = invalid-expression "pkg/front_end/testcases/general/implicit_instantiation.dart:20:7: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'int Function(int)'.
+  g = alias;
+      ^" in self::alias as{TypeError,ForNonNullableByDefault} (core::int) → core::int;
+  (core::int) → core::int h = invalid-expression "pkg/front_end/testcases/general/implicit_instantiation.dart:21:21: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'int Function(int)'.
+  int Function(int) h = c;
+                    ^" in (let final self::Class #t1 = c in #t1 == null ?{<T extends core::Object? = dynamic>(T%) → T%} null : #t1.{self::Class::call}{<T extends core::Object? = dynamic>(T%) → T%}) as{TypeError,ForNonNullableByDefault} (core::int) → core::int;
+  g = invalid-expression "pkg/front_end/testcases/general/implicit_instantiation.dart:22:3: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'int Function(int)'.
+  g = c;
+  ^" in (let final self::Class #t2 = c in #t2 == null ?{<T extends core::Object? = dynamic>(T%) → T%} null : #t2.{self::Class::call}{<T extends core::Object? = dynamic>(T%) → T%}) as{TypeError,ForNonNullableByDefault} (core::int) → core::int;
+  self::method(invalid-expression "pkg/front_end/testcases/general/implicit_instantiation.dart:23:10: Error: The argument type 'T Function<T>(T)' can't be assigned to the parameter type 'int Function(int)'.
+  method(alias);
+         ^" in self::alias as{TypeError,ForNonNullableByDefault} (core::int) → core::int);
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::id
+}
diff --git a/pkg/front_end/testcases/general/implicit_new.dart.weak.modular.expect b/pkg/front_end/testcases/general/implicit_new.dart.weak.modular.expect
new file mode 100644
index 0000000..908fc59
--- /dev/null
+++ b/pkg/front_end/testcases/general/implicit_new.dart.weak.modular.expect
@@ -0,0 +1,106 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/implicit_new.dart:18:18: Error: Couldn't find constructor 'Bar'.
+//   var y = prefix.Bar();
+//                  ^^^
+//
+// pkg/front_end/testcases/general/implicit_new.dart:19:10: Error: Couldn't find constructor 'Bar'.
+//   prefix.Bar();
+//          ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///implicit_new.dart" as prefix;
+
+class Foo extends core::Object {
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  operator +(dynamic other) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar extends core::Object {
+  constructor named() → self::Bar*
+    : super core::Object::•()
+    ;
+  operator +(dynamic other) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class IndexTester extends core::Object {
+  synthetic constructor •() → self::IndexTester*
+    : super core::Object::•()
+    ;
+  operator [](dynamic _) → dynamic
+    return null;
+  operator []=(dynamic _a, dynamic _b) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method testNSM() → dynamic {
+  invalid-type y = invalid-expression "pkg/front_end/testcases/general/implicit_new.dart:18:18: Error: Couldn't find constructor 'Bar'.
+  var y = prefix.Bar();
+                 ^^^";
+  invalid-expression "pkg/front_end/testcases/general/implicit_new.dart:19:10: Error: Couldn't find constructor 'Bar'.
+  prefix.Bar();
+         ^^^";
+}
+static method f(dynamic x) → dynamic
+  return x;
+static method main() → dynamic {
+  self::Foo* x = new self::Foo::•();
+  x = new self::Foo::•();
+  self::Bar* z = new self::Bar::named();
+  z = new self::Bar::named();
+  self::f(new self::Foo::•());
+  self::f(new self::Foo::•());
+  self::f(new self::Bar::named());
+  self::f(new self::Bar::named());
+  core::List<core::Object*>* l = <core::Object*>[new self::Foo::•(), new self::Bar::named()];
+  l = <core::Object*>[new self::Foo::•(), new self::Bar::named()];
+  core::Map<core::String*, core::Object*>* m = <core::String*, core::Object*>{"foo": new self::Foo::•(), "bar": new self::Bar::named()};
+  m = <core::String*, core::Object*>{"foo": new self::Foo::•(), "bar": new self::Bar::named()};
+  self::IndexTester* i = new self::IndexTester::•();
+  i.{self::IndexTester::[]}(new self::Foo::•()){(dynamic) →* dynamic};
+  i.{self::IndexTester::[]}(new self::Foo::•()){(dynamic) →* dynamic};
+  i.{self::IndexTester::[]}(new self::Bar::named()){(dynamic) →* dynamic};
+  i.{self::IndexTester::[]}(new self::Bar::named()){(dynamic) →* dynamic};
+  i.{self::IndexTester::[]=}(new self::Foo::•(), null){(dynamic, dynamic) →* void};
+  i.{self::IndexTester::[]=}(new self::Foo::•(), null){(dynamic, dynamic) →* void};
+  i.{self::IndexTester::[]=}(new self::Bar::named(), null){(dynamic, dynamic) →* void};
+  i.{self::IndexTester::[]=}(new self::Bar::named(), null){(dynamic, dynamic) →* void};
+  new self::Foo::•().{self::Foo::+}(new self::Bar::named()){(dynamic) →* dynamic};
+  new self::Foo::•().{self::Foo::+}(new self::Bar::named()){(dynamic) →* dynamic};
+  new self::Bar::named().{self::Bar::+}(new self::Foo::•()){(dynamic) →* dynamic};
+  new self::Bar::named().{self::Bar::+}(new self::Foo::•()){(dynamic) →* dynamic};
+}
diff --git a/pkg/front_end/testcases/general/implicit_new2.dart.weak.modular.expect b/pkg/front_end/testcases/general/implicit_new2.dart.weak.modular.expect
new file mode 100644
index 0000000..a487595
--- /dev/null
+++ b/pkg/front_end/testcases/general/implicit_new2.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:async" as asy;
+
+import "dart:async";
+
+static field void voidValue = null;
+static method main() → void {
+  self::test1();
+  self::test2();
+  self::test3();
+  self::test4();
+  self::test5();
+  self::test6();
+}
+static method test1() → FutureOr<FutureOr<void>> {}
+static method test2() → FutureOr<FutureOr<void>> {
+  return asy::Future::value<void>(0);
+}
+static method test3() → FutureOr<FutureOr<void>> {
+  return null as{ForNonNullableByDefault} FutureOr<void>;
+}
+static method test4() → FutureOr<FutureOr<void>> {
+  return asy::Future::value<asy::Future<void>>(asy::Future::value<void>(null));
+}
+static method test5() → FutureOr<FutureOr<void>> {
+  return 42;
+}
+static method test6() → FutureOr<FutureOr<void>> {
+  return asy::Future::value<FutureOr<void>?>(42);
+}
+static method test() → FutureOr<FutureOr<void>> {
+  return asy::Future::value<asy::Future<asy::Future<void>>>(asy::Future::value<asy::Future<void>>(asy::Future::value<void>(null)));
+}
diff --git a/pkg/front_end/testcases/general/implicit_scope_test.dart.weak.modular.expect b/pkg/front_end/testcases/general/implicit_scope_test.dart.weak.modular.expect
new file mode 100644
index 0000000..ef54b52
--- /dev/null
+++ b/pkg/front_end/testcases/general/implicit_scope_test.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+class ImplicitScopeTest extends core::Object {
+  synthetic constructor •() → self::ImplicitScopeTest*
+    : super core::Object::•()
+    ;
+  static method alwaysTrue() → core::bool* {
+    return 1.{core::num::+}(1){(core::num*) →* core::int*} =={core::num::==}{(core::Object*) →* core::bool*} 2;
+  }
+  static method testMain() → dynamic {
+    core::String* a = "foo";
+    dynamic b;
+    if(self::ImplicitScopeTest::alwaysTrue()) {
+      core::String* a = "bar";
+    }
+    else {
+      core::String* b = a;
+    }
+    exp::Expect::equals("foo", a);
+    exp::Expect::equals(null, b);
+    while (!self::ImplicitScopeTest::alwaysTrue()) {
+      core::String* a = "bar";
+      core::String* b = "baz";
+    }
+    exp::Expect::equals("foo", a);
+    exp::Expect::equals(null, b);
+    for (core::int* i = 0; i.{core::num::<}(10){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+      core::String* a = "bar";
+      core::String* b = "baz";
+    }
+    exp::Expect::equals("foo", a);
+    exp::Expect::equals(null, b);
+    do {
+      core::String* a = "bar";
+      core::String* b = "baz";
+    }
+    while ("black" =={core::String::==}{(core::Object*) →* core::bool*} "white")
+    exp::Expect::equals("foo", a);
+    exp::Expect::equals(null, b);
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::ImplicitScopeTest::testMain();
+}
diff --git a/pkg/front_end/testcases/general/implicit_super_call.dart.weak.modular.expect b/pkg/front_end/testcases/general/implicit_super_call.dart.weak.modular.expect
new file mode 100644
index 0000000..f6e3ccb
--- /dev/null
+++ b/pkg/front_end/testcases/general/implicit_super_call.dart.weak.modular.expect
@@ -0,0 +1,190 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/implicit_super_call.dart:67:5: Error: Cannot invoke `super` because it declares 'call' to be something other than a method.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+//     super(0); // error
+//     ^
+//
+// pkg/front_end/testcases/general/implicit_super_call.dart:81:5: Error: Cannot invoke `super` because it declares 'call' to be something other than a method.
+// Try changing 'call' to a method or explicitly invoke 'call'.
+//     super(0); // error
+//     ^
+//
+// pkg/front_end/testcases/general/implicit_super_call.dart:95:5: Error: Superclass has no method named 'call'.
+//     super(0); // error
+//     ^^^^
+//
+// pkg/front_end/testcases/general/implicit_super_call.dart:96:11: Error: Superclass has no method named 'call'.
+//     super.call(0); // error
+//           ^^^^
+//
+// pkg/front_end/testcases/general/implicit_super_call.dart:104:5: Error: Superclass has no method named 'call'.
+//     super(); // error
+//     ^^^^
+//
+// pkg/front_end/testcases/general/implicit_super_call.dart:105:11: Error: Superclass has no method named 'call'.
+//     super.call(); // error
+//           ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super1 extends core::Object {
+  synthetic constructor •() → self::Super1
+    : super core::Object::•()
+    ;
+  method call() → void {}
+}
+class Class1 extends self::Super1 {
+  synthetic constructor •() → self::Class1
+    : super self::Super1::•()
+    ;
+  method method() → void {
+    super.{self::Super1::call}();
+    super.{self::Super1::call}();
+  }
+}
+class Super2 extends core::Object {
+  synthetic constructor •() → self::Super2
+    : super core::Object::•()
+    ;
+  method call(core::int a, [core::int? b = #C1]) → core::int
+    return a;
+}
+class Class2 extends self::Super2 {
+  synthetic constructor •() → self::Class2
+    : super self::Super2::•()
+    ;
+  method method() → void {
+    super.{self::Super2::call}(0);
+    super.{self::Super2::call}(0, 1);
+    super.{self::Super2::call}(0);
+    super.{self::Super2::call}(0, 1);
+  }
+}
+class Super3 extends core::Object {
+  synthetic constructor •() → self::Super3
+    : super core::Object::•()
+    ;
+  method call(core::int a, {core::int? b = #C1, core::int? c = #C1}) → core::int
+    return a;
+}
+class Class3 extends self::Super3 {
+  synthetic constructor •() → self::Class3
+    : super self::Super3::•()
+    ;
+  method method() → void {
+    super.{self::Super3::call}(0);
+    super.{self::Super3::call}(0, b: 1);
+    super.{self::Super3::call}(0, c: 1);
+    super.{self::Super3::call}(0, b: 1, c: 2);
+    super.{self::Super3::call}(0, c: 1, b: 2);
+    super.{self::Super3::call}(0);
+    super.{self::Super3::call}(0, b: 1);
+    super.{self::Super3::call}(0, c: 1);
+    super.{self::Super3::call}(0, b: 1, c: 2);
+    super.{self::Super3::call}(0, c: 1, b: 2);
+  }
+}
+class Super4 extends core::Object {
+  synthetic constructor •() → self::Super4
+    : super core::Object::•()
+    ;
+  method call<T extends core::Object? = dynamic>(self::Super4::call::T% a) → self::Super4::call::T%
+    return a;
+}
+class Class4 extends self::Super4 {
+  synthetic constructor •() → self::Class4
+    : super self::Super4::•()
+    ;
+  method method() → void {
+    super.{self::Super4::call}<core::int>(0);
+    super.{self::Super4::call}<core::int>(0);
+    super.{self::Super4::call}<core::int>(0);
+    super.{self::Super4::call}<core::int>(0);
+  }
+}
+class Super5 extends core::Object {
+  synthetic constructor •() → self::Super5
+    : super core::Object::•()
+    ;
+  get call() → (core::int) → core::int
+    return (core::int a) → core::int => a;
+}
+class Class5 extends self::Super5 {
+  synthetic constructor •() → self::Class5
+    : super self::Super5::•()
+    ;
+  method test() → void {
+    invalid-expression "pkg/front_end/testcases/general/implicit_super_call.dart:67:5: Error: Cannot invoke `super` because it declares 'call' to be something other than a method.
+Try changing 'call' to a method or explicitly invoke 'call'.
+    super(0); // error
+    ^";
+  }
+  method method() → void {
+    super.{self::Super5::call}(0){(core::int) → core::int};
+  }
+}
+class Super6 extends core::Object {
+  field (core::int) → core::int call = (core::int a) → core::int => a;
+  synthetic constructor •() → self::Super6
+    : super core::Object::•()
+    ;
+}
+class Class6 extends self::Super6 {
+  synthetic constructor •() → self::Class6
+    : super self::Super6::•()
+    ;
+  method test() → void {
+    invalid-expression "pkg/front_end/testcases/general/implicit_super_call.dart:81:5: Error: Cannot invoke `super` because it declares 'call' to be something other than a method.
+Try changing 'call' to a method or explicitly invoke 'call'.
+    super(0); // error
+    ^";
+  }
+  method method() → void {
+    super.{self::Super6::call}(0){(core::int) → core::int};
+  }
+}
+class Super7 extends core::Object {
+  synthetic constructor •() → self::Super7
+    : super core::Object::•()
+    ;
+  set call((core::int) → core::int value) → void {}
+}
+class Class7 extends self::Super7 {
+  synthetic constructor •() → self::Class7
+    : super self::Super7::•()
+    ;
+  method test() → void {
+    super.call(0);
+    super.call(0);
+  }
+}
+class Super8 extends core::Object {
+  synthetic constructor •() → self::Super8
+    : super core::Object::•()
+    ;
+}
+class Class8 extends self::Super8 {
+  synthetic constructor •() → self::Class8
+    : super self::Super8::•()
+    ;
+  method test() → void {
+    super.call();
+    super.call();
+  }
+}
+static method main() → dynamic {
+  new self::Class1::•().{self::Class1::method}(){() → void};
+  new self::Class2::•().{self::Class2::method}(){() → void};
+  new self::Class3::•().{self::Class3::method}(){() → void};
+  new self::Class4::•().{self::Class4::method}(){() → void};
+  new self::Class5::•().{self::Class5::method}(){() → void};
+  new self::Class6::•().{self::Class6::method}(){() → void};
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/implicit_this.dart.weak.modular.expect b/pkg/front_end/testcases/general/implicit_this.dart.weak.modular.expect
new file mode 100644
index 0000000..23d7a44
--- /dev/null
+++ b/pkg/front_end/testcases/general/implicit_this.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method m() → dynamic {
+    core::print("Called m");
+  }
+  method testC() → dynamic {
+    this.{self::C::m}(){() →* dynamic};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method testD() → dynamic {
+    this.{self::C::m}(){() →* dynamic};
+  }
+}
+static method main() → dynamic {
+  new self::C::•().{self::C::testC}(){() →* dynamic};
+  new self::D::•().{self::D::testD}(){() →* dynamic};
+}
diff --git a/pkg/front_end/testcases/general/import_conflicting_getters.dart.weak.modular.expect b/pkg/front_end/testcases/general/import_conflicting_getters.dart.weak.modular.expect
new file mode 100644
index 0000000..14ee367
--- /dev/null
+++ b/pkg/front_end/testcases/general/import_conflicting_getters.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/import_conflicting_getters.dart:11:9: Error: 'foo' is imported from both 'pkg/front_end/testcases/general/import_conflicting_getters_lib1.dart' and 'pkg/front_end/testcases/general/import_conflicting_getters_lib2.dart'.
+//   print(foo);
+//         ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///import_conflicting_getters_lib1.dart";
+import "org-dartlang-testcase:///import_conflicting_getters_lib2.dart";
+
+static method main() → dynamic {}
+static method errors() → dynamic {
+  core::print(invalid-expression "pkg/front_end/testcases/general/import_conflicting_getters.dart:11:9: Error: 'foo' is imported from both 'pkg/front_end/testcases/general/import_conflicting_getters_lib1.dart' and 'pkg/front_end/testcases/general/import_conflicting_getters_lib2.dart'.
+  print(foo);
+        ^^^");
+}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+static get foo() → core::int*
+  return 42;
+
+library;
+import self as self3;
+import "dart:core" as core;
+
+static get foo() → core::int*
+  return 87;
diff --git a/pkg/front_end/testcases/general/import_conflicting_setters.dart.weak.modular.expect b/pkg/front_end/testcases/general/import_conflicting_setters.dart.weak.modular.expect
new file mode 100644
index 0000000..26d7537
--- /dev/null
+++ b/pkg/front_end/testcases/general/import_conflicting_setters.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/import_conflicting_setters.dart:11:3: Error: Setter not found: 'foo'.
+//   foo = 42;
+//   ^^^
+//
+import self as self;
+
+import "org-dartlang-testcase:///import_conflicting_setters_lib1.dart";
+import "org-dartlang-testcase:///import_conflicting_setters_lib2.dart";
+
+static method main() → dynamic {}
+static method errors() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/import_conflicting_setters.dart:11:3: Error: Setter not found: 'foo'.
+  foo = 42;
+  ^^^";
+}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+static set foo(core::int* value) → void {}
+
+library;
+import self as self3;
+import "dart:core" as core;
+
+static set foo(core::int* value) → void {}
diff --git a/pkg/front_end/testcases/general/import_conflicting_type_member.dart.weak.modular.expect b/pkg/front_end/testcases/general/import_conflicting_type_member.dart.weak.modular.expect
new file mode 100644
index 0000000..d883515
--- /dev/null
+++ b/pkg/front_end/testcases/general/import_conflicting_type_member.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/import_conflicting_type_member.dart:6:1: Error: 'Foo' is imported from both 'pkg/front_end/testcases/general/import_conflicting_type_member_lib1.dart' and 'pkg/front_end/testcases/general/import_conflicting_type_member_lib2.dart'.
+// import 'import_conflicting_type_member_lib2.dart';
+// ^^^
+//
+// pkg/front_end/testcases/general/import_conflicting_type_member.dart:12:3: Error: 'Foo' is imported from both 'pkg/front_end/testcases/general/import_conflicting_type_member_lib1.dart' and 'pkg/front_end/testcases/general/import_conflicting_type_member_lib2.dart'.
+//   Foo();
+//   ^^^
+//
+import self as self;
+
+import "org-dartlang-testcase:///import_conflicting_type_member_lib1.dart";
+import "org-dartlang-testcase:///import_conflicting_type_member_lib2.dart";
+
+static method main() → dynamic {}
+static method errors() → dynamic {
+  invalid-type foo;
+  invalid-expression "pkg/front_end/testcases/general/import_conflicting_type_member.dart:12:3: Error: 'Foo' is imported from both 'pkg/front_end/testcases/general/import_conflicting_type_member_lib1.dart' and 'pkg/front_end/testcases/general/import_conflicting_type_member_lib2.dart'.
+  Foo();
+  ^^^";
+}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → self2::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+library;
+import self as self3;
+
+static method Foo() → dynamic {}
diff --git a/pkg/front_end/testcases/general/import_conflicting_types.dart.weak.modular.expect b/pkg/front_end/testcases/general/import_conflicting_types.dart.weak.modular.expect
new file mode 100644
index 0000000..6154f37
--- /dev/null
+++ b/pkg/front_end/testcases/general/import_conflicting_types.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/import_conflicting_types.dart:6:1: Error: 'Foo' is imported from both 'pkg/front_end/testcases/general/import_conflicting_types_lib1.dart' and 'pkg/front_end/testcases/general/import_conflicting_types_lib2.dart'.
+// import 'import_conflicting_types_lib2.dart';
+// ^^^
+//
+import self as self;
+
+import "org-dartlang-testcase:///import_conflicting_types_lib1.dart";
+import "org-dartlang-testcase:///import_conflicting_types_lib2.dart";
+
+static method main() → dynamic {}
+static method errors() → dynamic {
+  invalid-type foo;
+}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → self2::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+library;
+import self as self3;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → self3::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/general/incomplete_field_formal_parameter.dart.weak.modular.expect b/pkg/front_end/testcases/general/incomplete_field_formal_parameter.dart.weak.modular.expect
new file mode 100644
index 0000000..2967d68
--- /dev/null
+++ b/pkg/front_end/testcases/general/incomplete_field_formal_parameter.dart.weak.modular.expect
@@ -0,0 +1,51 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/incomplete_field_formal_parameter.dart:6:7: Error: 'this' can't be used as an identifier because it's a keyword.
+// Try renaming this to be an identifier that isn't a keyword.
+//   C.a(this);
+//       ^^^^
+//
+// pkg/front_end/testcases/general/incomplete_field_formal_parameter.dart:7:12: Error: Expected an identifier, but got ')'.
+// Try inserting an identifier before ')'.
+//   C.b(this.);
+//            ^
+//
+// pkg/front_end/testcases/general/incomplete_field_formal_parameter.dart:8:7: Error: 'this' can't be used as an identifier because it's a keyword.
+// Try renaming this to be an identifier that isn't a keyword.
+//   C.c(this, p);
+//       ^^^^
+//
+// pkg/front_end/testcases/general/incomplete_field_formal_parameter.dart:9:12: Error: Expected an identifier, but got ','.
+// Try inserting an identifier before ','.
+//   C.d(this., p);
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  constructor a(dynamic this) → self::C*
+    : super core::Object::•()
+    ;
+  constructor b() → self::C*
+    : super core::Object::•()
+    ;
+  constructor c(dynamic this, dynamic p) → self::C*
+    : super core::Object::•()
+    ;
+  constructor d() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/general/infer_equals.dart.weak.modular.expect b/pkg/front_end/testcases/general/infer_equals.dart.weak.modular.expect
new file mode 100644
index 0000000..4b8aa53e
--- /dev/null
+++ b/pkg/front_end/testcases/general/infer_equals.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field dynamic field = null;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  operator ==(dynamic o) → core::bool* {
+    if(!(o is self::Class*))
+      return false;
+    return this.{self::Class::field}{dynamic} =={core::Object::==}{(core::Object*) →* core::bool*} o{dynamic}.field;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/infer_field_from_multiple.dart.weak.modular.expect b/pkg/front_end/testcases/general/infer_field_from_multiple.dart.weak.modular.expect
new file mode 100644
index 0000000..4796a9b
--- /dev/null
+++ b/pkg/front_end/testcases/general/infer_field_from_multiple.dart.weak.modular.expect
@@ -0,0 +1,297 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:49:7: Error: Can't infer a type for 'field2' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var field2; // error
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:7:7: Context: This is one of the overridden members.
+//   var field2 = 0;
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:28:7: Context: This is one of the overridden members.
+//   var field2 = '';
+//       ^^^^^^
+//
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:51:7: Error: Can't infer a type for 'field4' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var field4 = 0; // error
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:9:7: Context: This is one of the overridden members.
+//   var field4 = 0;
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:30:7: Context: This is one of the overridden members.
+//   var field4 = '';
+//       ^^^^^^
+//
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:53:7: Error: Can't infer a type for 'field6' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var field6; // error
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:11:7: Context: This is one of the overridden members.
+//   int field6;
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:32:10: Context: This is one of the overridden members.
+//   String field6;
+//          ^^^^^^
+//
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:55:7: Error: Can't infer a type for 'field8' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var field8 = 0; // error
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:13:7: Context: This is one of the overridden members.
+//   int field8;
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:34:10: Context: This is one of the overridden members.
+//   String field8;
+//          ^^^^^^
+//
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:58:7: Error: Can't infer a type for 'field11' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var field11; // error
+//       ^^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:16:5: Context: This is one of the overridden members.
+//   T field11;
+//     ^^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:37:5: Context: This is one of the overridden members.
+//   S field11;
+//     ^^^^^^^
+//
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:64:7: Error: Can't infer a type for 'field17' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var field17; // error
+//       ^^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:22:7: Context: This is one of the overridden members.
+//   var field17 = 0;
+//       ^^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:43:10: Context: This is one of the overridden members.
+//   String field17;
+//          ^^^^^^^
+//
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:65:7: Error: Can't infer a type for 'field18' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var field18; // error
+//       ^^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:23:7: Context: This is one of the overridden members.
+//   int field18;
+//       ^^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:44:7: Context: This is one of the overridden members.
+//   var field18 = '';
+//       ^^^^^^^
+//
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:90:7: Error: Can't infer a type for 'field2' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var field2; // error
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:7:7: Context: This is one of the overridden members.
+//   var field2 = 0;
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:28:7: Context: This is one of the overridden members.
+//   var field2 = '';
+//       ^^^^^^
+//
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:92:7: Error: Can't infer a type for 'field4' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var field4 = 0; // error
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:9:7: Context: This is one of the overridden members.
+//   var field4 = 0;
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:30:7: Context: This is one of the overridden members.
+//   var field4 = '';
+//       ^^^^^^
+//
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:94:7: Error: Can't infer a type for 'field6' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var field6; // error
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:11:7: Context: This is one of the overridden members.
+//   int field6;
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:32:10: Context: This is one of the overridden members.
+//   String field6;
+//          ^^^^^^
+//
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:96:7: Error: Can't infer a type for 'field8' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var field8 = 0; // error
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:13:7: Context: This is one of the overridden members.
+//   int field8;
+//       ^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:34:10: Context: This is one of the overridden members.
+//   String field8;
+//          ^^^^^^
+//
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:105:7: Error: Can't infer a type for 'field17' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var field17; // error
+//       ^^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:22:7: Context: This is one of the overridden members.
+//   var field17 = 0;
+//       ^^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:43:10: Context: This is one of the overridden members.
+//   String field17;
+//          ^^^^^^^
+//
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:106:7: Error: Can't infer a type for 'field18' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var field18; // error
+//       ^^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:23:7: Context: This is one of the overridden members.
+//   int field18;
+//       ^^^^^^^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:44:7: Context: This is one of the overridden members.
+//   var field18 = '';
+//       ^^^^^^^
+//
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:61:7: Error: The return type of the method 'C.field14' is 'int', which does not match the return type, 'String', of the overridden method, 'B.field14'.
+// Change to a subtype of 'String'.
+//   int field14; // error
+//       ^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:40:5: Context: This is the overridden method ('field14').
+//   S field14;
+//     ^
+//
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:61:7: Error: The field 'C.field14' has type 'int', which does not match the corresponding type, 'String', in the overridden setter, 'B.field14'.
+//   int field14; // error
+//       ^
+// pkg/front_end/testcases/general/infer_field_from_multiple.dart:40:5: Context: This is the overridden method ('field14').
+//   S field14;
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  field core::int* field1 = 0;
+  field core::int* field2 = 0;
+  field core::int* field3 = 0;
+  field core::int* field4 = 0;
+  field core::int* field5 = null;
+  field core::int* field6 = null;
+  field core::int* field7 = null;
+  field core::int* field8 = null;
+  field dynamic field9 = null;
+  covariant-by-class field self::A::T* field10 = null;
+  covariant-by-class field self::A::T* field11 = null;
+  covariant-by-class field self::A::T* field12 = null;
+  covariant-by-class field self::A::T* field13 = null;
+  covariant-by-class field self::A::T* field14 = null;
+  field core::int* field15 = 0;
+  field core::int* field16 = null;
+  field core::int* field17 = 0;
+  field core::int* field18 = null;
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::Object* = dynamic, S extends core::Object* = dynamic> extends core::Object {
+  field core::int* field1 = 1;
+  field core::String* field2 = "";
+  field core::int* field3 = 1;
+  field core::String* field4 = "";
+  field core::int* field5 = null;
+  field core::String* field6 = null;
+  field core::int* field7 = null;
+  field core::String* field8 = null;
+  field dynamic field9 = null;
+  covariant-by-class field self::B::T* field10 = null;
+  covariant-by-class field self::B::S* field11 = null;
+  covariant-by-class field self::B::T* field12 = null;
+  covariant-by-class field self::B::T* field13 = null;
+  covariant-by-class field self::B::S* field14 = null;
+  field core::int* field15 = null;
+  field core::int* field16 = 0;
+  field core::String* field17 = null;
+  field core::String* field18 = "";
+  synthetic constructor •() → self::B<self::B::T*, self::B::S*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object implements self::A<core::int*>, self::B<core::int*, core::String*> {
+  field core::int* field1;
+  field invalid-type field2;
+  field core::int* field3 = 0;
+  field invalid-type field4 = 0;
+  field core::int* field5;
+  field invalid-type field6;
+  field core::int* field7 = 0;
+  field invalid-type field8 = 0;
+  field dynamic field9;
+  covariant-by-class field core::int* field10;
+  covariant-by-class field invalid-type field11;
+  covariant-by-class field core::int* field12;
+  covariant-by-class field core::int* field13 = 0;
+  covariant-by-class field core::int* field14;
+  field core::int* field15;
+  field core::int* field16;
+  field invalid-type field17;
+  field invalid-type field18;
+  constructor •(core::int* field1, invalid-type field2, core::int* field3, invalid-type field4, core::int* field5, invalid-type field6, core::int* field7, invalid-type field8, dynamic field9, core::int* field10, invalid-type field11, core::int* field12, core::int* field13, core::int* field14, core::int* field15, core::int* field16, invalid-type field17, invalid-type field18) → self::C*
+    : self::C::field1 = field1, self::C::field2 = field2, self::C::field3 = field3, self::C::field4 = field4, self::C::field5 = field5, self::C::field6 = field6, self::C::field7 = field7, self::C::field8 = field8, self::C::field9 = field9, self::C::field10 = field10, self::C::field11 = field11, self::C::field12 = field12, self::C::field13 = field13, self::C::field14 = field14, self::C::field15 = field15, self::C::field16 = field16, self::C::field17 = field17, self::C::field18 = field18, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<T extends core::Object* = dynamic> extends core::Object implements self::A<self::D::T*>, self::B<self::D::T*, self::D::T*> {
+  field core::int* field1;
+  field invalid-type field2;
+  field core::int* field3 = 0;
+  field invalid-type field4 = 0;
+  field core::int* field5;
+  field invalid-type field6;
+  field core::int* field7 = 0;
+  field invalid-type field8 = 0;
+  field dynamic field9;
+  covariant-by-class field self::D::T* field10;
+  covariant-by-class field self::D::T* field11;
+  covariant-by-class field self::D::T* field12;
+  covariant-by-class field self::D::T* field13 = null;
+  covariant-by-class field self::D::T* field14;
+  field core::int* field15;
+  field core::int* field16;
+  field invalid-type field17;
+  field invalid-type field18;
+  constructor •(core::int* field1, invalid-type field2, core::int* field3, invalid-type field4, core::int* field5, invalid-type field6, core::int* field7, invalid-type field8, dynamic field9, self::D::T* field10, self::D::T* field11, self::D::T* field12, self::D::T* field13, self::D::T* field14, core::int* field15, core::int* field16, invalid-type field17, invalid-type field18) → self::D<self::D::T*>*
+    : self::D::field1 = field1, self::D::field2 = field2, self::D::field3 = field3, self::D::field4 = field4, self::D::field5 = field5, self::D::field6 = field6, self::D::field7 = field7, self::D::field8 = field8, self::D::field9 = field9, self::D::field10 = field10, self::D::field11 = field11, self::D::field12 = field12, self::D::field13 = field13, self::D::field14 = field14, self::D::field15 = field15, self::D::field16 = field16, self::D::field17 = field17, self::D::field18 = field18, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/general/infer_field_type.dart.weak.modular.expect b/pkg/front_end/testcases/general/infer_field_type.dart.weak.modular.expect
new file mode 100644
index 0000000..aa6a7e49
--- /dev/null
+++ b/pkg/front_end/testcases/general/infer_field_type.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class C extends self::B {
+  field core::int* field = null;
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  get field() → core::int*
+    return null;
+  set field(core::int* value) → void {}
+}
+class A extends core::Object {
+  field core::int* field = 0;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* topLevelFieldFromA = new self::A::•().{self::A::field}{core::int*};
+static field core::int* topLevelFieldFromB = new self::B::•().{self::B::field}{core::int*};
+static field core::int* topLevelFieldFromC = new self::C::•().{self::C::field}{core::int*};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/infer_fixed_generic_return_type.dart.weak.modular.expect b/pkg/front_end/testcases/general/infer_fixed_generic_return_type.dart.weak.modular.expect
new file mode 100644
index 0000000..bf294a6
--- /dev/null
+++ b/pkg/front_end/testcases/general/infer_fixed_generic_return_type.dart.weak.modular.expect
@@ -0,0 +1,127 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class Base extends core::Object {
+  synthetic constructor •() → self::Base*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class MixinA<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::MixinA<self::MixinA::T*>*
+    : super core::Object::•()
+    ;
+  abstract method method(core::Object* t) → self::MixinA::T*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Class&Base&MixinA = self::Base with self::MixinA<dynamic> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Base&MixinA*
+    : super self::Base::•()
+    ;
+  abstract mixin-stub method method(core::Object* t) → dynamic; -> self::MixinA::method
+}
+abstract class Class extends self::_Class&Base&MixinA {
+  synthetic constructor •() → self::Class*
+    : super self::_Class&Base&MixinA::•()
+    ;
+  method method(core::Object* t) → dynamic {}
+}
+abstract class YamlNode extends core::Object {
+  synthetic constructor •() → self::YamlNode*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Map<K extends core::Object* = dynamic, V extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Map<self::Map::K*, self::Map::V*>*
+    : super core::Object::•()
+    ;
+  abstract operator [](core::Object* key) → self::Map::V*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class MapMixin<K extends core::Object* = dynamic, V extends core::Object* = dynamic> extends core::Object implements self::Map<self::MapMixin::K*, self::MapMixin::V*> {
+  synthetic constructor •() → self::MapMixin<self::MapMixin::K*, self::MapMixin::V*>*
+    : super core::Object::•()
+    ;
+  abstract operator [](core::Object* key) → self::MapMixin::V*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class UnmodifiableMapMixin<K extends core::Object* = dynamic, V extends core::Object* = dynamic> extends core::Object implements self::Map<self::UnmodifiableMapMixin::K*, self::UnmodifiableMapMixin::V*> {
+  synthetic constructor •() → self::UnmodifiableMapMixin<self::UnmodifiableMapMixin::K*, self::UnmodifiableMapMixin::V*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _YamlMap&YamlNode&MapMixin = self::YamlNode with self::MapMixin<dynamic, dynamic> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_YamlMap&YamlNode&MapMixin*
+    : super self::YamlNode::•()
+    ;
+  abstract mixin-stub operator [](core::Object* key) → dynamic; -> self::MapMixin::[]
+}
+abstract class _YamlMap&YamlNode&MapMixin&UnmodifiableMapMixin = self::_YamlMap&YamlNode&MapMixin with self::UnmodifiableMapMixin<dynamic, dynamic> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_YamlMap&YamlNode&MapMixin&UnmodifiableMapMixin*
+    : super self::_YamlMap&YamlNode&MapMixin::•()
+    ;
+}
+class YamlMap extends self::_YamlMap&YamlNode&MapMixin&UnmodifiableMapMixin {
+  synthetic constructor •() → self::YamlMap*
+    : super self::_YamlMap&YamlNode&MapMixin&UnmodifiableMapMixin::•()
+    ;
+  operator [](core::Object* key) → dynamic {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart.weak.modular.expect b/pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart.weak.modular.expect
new file mode 100644
index 0000000..4574621
--- /dev/null
+++ b/pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart.weak.modular.expect
@@ -0,0 +1,100 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:9:10: Error: A value of type 'S Function<S>(S, S)' can't be assigned to a variable of type 'int Function(int, int)'.
+//   d = <S>(S a, S b) => a;
+//          ^
+//
+// pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:15:7: Error: A value of type 'S Function<S>(S, S)' can't be assigned to a variable of type 'int Function(int, int)'.
+//   d = f;
+//       ^
+//
+// pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:20:10: Error: A value of type 'dynamic Function<S>(dynamic, S)' can't be assigned to a variable of type 'int Function(int, int)'.
+//   d = <S>(a, S b) => a;
+//          ^
+//
+// pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:25:10: Error: A value of type 'S Function<S>(dynamic, S)' can't be assigned to a variable of type 'int Function(int, int)'.
+//   d = <S>(a, S b) => b;
+//          ^
+//
+// pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:30:10: Error: A value of type 'dynamic Function<S>(dynamic, dynamic)' can't be assigned to a variable of type 'int Function(int, int)'.
+//   d = <S>(a, b) => a;
+//          ^
+//
+// pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:35:7: Error: A value of type 'int Function(int, int, dynamic)' can't be assigned to a variable of type 'int Function(int, int)'.
+//   d = (a, b, c) => a;
+//       ^
+//
+// pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:40:7: Error: A value of type 'int Function(int)' can't be assigned to a variable of type 'int Function(int, int)'.
+//   d = (a) => a;
+//       ^
+//
+// pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:45:10: Error: A value of type 'dynamic Function<S>(dynamic, dynamic, dynamic)' can't be assigned to a variable of type 'int Function(int, int)'.
+//   d = <S>(a, b, c) => a;
+//          ^
+//
+// pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:50:10: Error: A value of type 'dynamic Function<S>(dynamic)' can't be assigned to a variable of type 'int Function(int, int)'.
+//   d = <S>(a) => a;
+//          ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F<invariant T extends core::Object* = dynamic> = (T*, T*) →* T*;
+static method test1() → dynamic {
+  (core::int*, core::int*) →* core::int* d = (core::int* a, core::int* b) → core::int* => a;
+  d = invalid-expression "pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:9:10: Error: A value of type 'S Function<S>(S, S)' can't be assigned to a variable of type 'int Function(int, int)'.
+  d = <S>(S a, S b) => a;
+         ^" in (<S extends core::Object* = dynamic>(S* a, S* b) → S* => a) as{TypeError} (core::int*, core::int*) →* core::int*;
+}
+static method test2() → dynamic {
+  (core::int*, core::int*) →* core::int* d = (core::int* a, core::int* b) → core::int* => a;
+  <S extends core::Object* = dynamic>(S*, S*) →* S* f = <S extends core::Object* = dynamic>(S* a, S* b) → S* => a;
+  d = invalid-expression "pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:15:7: Error: A value of type 'S Function<S>(S, S)' can't be assigned to a variable of type 'int Function(int, int)'.
+  d = f;
+      ^" in f as{TypeError} (core::int*, core::int*) →* core::int*;
+}
+static method test3a() → dynamic {
+  (core::int*, core::int*) →* core::int* d = (core::int* a, core::int* b) → core::int* => a;
+  d = invalid-expression "pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:20:10: Error: A value of type 'dynamic Function<S>(dynamic, S)' can't be assigned to a variable of type 'int Function(int, int)'.
+  d = <S>(a, S b) => a;
+         ^" in (<S extends core::Object* = dynamic>(dynamic a, S* b) → dynamic => a) as{TypeError} (core::int*, core::int*) →* core::int*;
+}
+static method test3b() → dynamic {
+  (core::int*, core::int*) →* core::int* d = (core::int* a, core::int* b) → core::int* => a;
+  d = invalid-expression "pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:25:10: Error: A value of type 'S Function<S>(dynamic, S)' can't be assigned to a variable of type 'int Function(int, int)'.
+  d = <S>(a, S b) => b;
+         ^" in (<S extends core::Object* = dynamic>(dynamic a, S* b) → S* => b) as{TypeError} (core::int*, core::int*) →* core::int*;
+}
+static method test4() → dynamic {
+  (core::int*, core::int*) →* core::int* d = (core::int* a, core::int* b) → core::int* => a;
+  d = invalid-expression "pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:30:10: Error: A value of type 'dynamic Function<S>(dynamic, dynamic)' can't be assigned to a variable of type 'int Function(int, int)'.
+  d = <S>(a, b) => a;
+         ^" in (<S extends core::Object* = dynamic>(dynamic a, dynamic b) → dynamic => a) as{TypeError} (core::int*, core::int*) →* core::int*;
+}
+static method test5() → dynamic {
+  (core::int*, core::int*) →* core::int* d = (core::int* a, core::int* b) → core::int* => a;
+  d = invalid-expression "pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:35:7: Error: A value of type 'int Function(int, int, dynamic)' can't be assigned to a variable of type 'int Function(int, int)'.
+  d = (a, b, c) => a;
+      ^" in ((core::int* a, core::int* b, dynamic c) → core::int* => a) as{TypeError} (core::int*, core::int*) →* core::int*;
+}
+static method test6() → dynamic {
+  (core::int*, core::int*) →* core::int* d = (core::int* a, core::int* b) → core::int* => a;
+  d = invalid-expression "pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:40:7: Error: A value of type 'int Function(int)' can't be assigned to a variable of type 'int Function(int, int)'.
+  d = (a) => a;
+      ^" in ((core::int* a) → core::int* => a) as{TypeError} (core::int*, core::int*) →* core::int*;
+}
+static method test7() → dynamic {
+  (core::int*, core::int*) →* core::int* d = (core::int* a, core::int* b) → core::int* => a;
+  d = invalid-expression "pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:45:10: Error: A value of type 'dynamic Function<S>(dynamic, dynamic, dynamic)' can't be assigned to a variable of type 'int Function(int, int)'.
+  d = <S>(a, b, c) => a;
+         ^" in (<S extends core::Object* = dynamic>(dynamic a, dynamic b, dynamic c) → dynamic => a) as{TypeError} (core::int*, core::int*) →* core::int*;
+}
+static method test8() → dynamic {
+  (core::int*, core::int*) →* core::int* d = (core::int* a, core::int* b) → core::int* => a;
+  d = invalid-expression "pkg/front_end/testcases/general/infer_generic_type_parameter_mismatch.dart:50:10: Error: A value of type 'dynamic Function<S>(dynamic)' can't be assigned to a variable of type 'int Function(int, int)'.
+  d = <S>(a) => a;
+         ^" in (<S extends core::Object* = dynamic>(dynamic a) → dynamic => a) as{TypeError} (core::int*, core::int*) →* core::int*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/infer_map_literal_with_closure.dart.weak.modular.expect b/pkg/front_end/testcases/general/infer_map_literal_with_closure.dart.weak.modular.expect
new file mode 100644
index 0000000..4e6b1e4
--- /dev/null
+++ b/pkg/front_end/testcases/general/infer_map_literal_with_closure.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::Map<core::String*, (core::String*) →* Null>* map = <core::String*, (core::String*) →* Null>{"foo": (core::String* a) → Null {
+    core::int* c = a.{core::String::length}{core::int*};
+  }};
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/inherit_function.dart.weak.modular.expect b/pkg/front_end/testcases/general/inherit_function.dart.weak.modular.expect
new file mode 100644
index 0000000..8b7e846
--- /dev/null
+++ b/pkg/front_end/testcases/general/inherit_function.dart.weak.modular.expect
@@ -0,0 +1,70 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&Object&Function extends core::Object {
+  synthetic constructor •() → self::_C&Object&Function*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::_C&Object&Function {
+  synthetic constructor •() → self::C*
+    : super self::_C&Object&Function::•()
+    ;
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/initialzation_errors.dart.weak.modular.expect b/pkg/front_end/testcases/general/initialzation_errors.dart.weak.modular.expect
new file mode 100644
index 0000000..fc29ac4
--- /dev/null
+++ b/pkg/front_end/testcases/general/initialzation_errors.dart.weak.modular.expect
@@ -0,0 +1,321 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:9:16: Error: 'x' was already initialized by this constructor.
+//         this.x = 42 {}
+//                ^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:16:16: Error: 'x' was already initialized by this constructor.
+//         this.x = 42 {}
+//                ^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:22:16: Error: 'x' is a final instance variable that was initialized at the declaration.
+//       : this.x = 41,
+//                ^
+// pkg/front_end/testcases/general/initialzation_errors.dart:20:13: Context: 'x' was initialized here.
+//   final int x = 2;
+//             ^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:23:16: Error: 'x' was already initialized by this constructor.
+//         this.x = 42 {}
+//                ^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:30:16: Error: A redirecting constructor can't have other initializers.
+//       : this.x = 41,
+//                ^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:32:16: Error: A redirecting constructor can't have other initializers.
+//         this.y = 42 {}
+//                ^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:43:16: Error: A redirecting constructor can't have other initializers.
+//         this.x = 1,
+//                ^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:44:16: Error: A redirecting constructor can't have other initializers.
+//         this.y = 2 {}
+//                ^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:49:16: Error: A redirecting constructor can't have other initializers.
+//       : this.x = 1,
+//                ^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:51:16: Error: A redirecting constructor can't have other initializers.
+//         this.y = 2;
+//                ^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:53:9: Error: A redirecting constructor can't have a 'super' initializer.
+//       : super(),
+//         ^^^^^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:55:16: Error: Can't have initializers after 'super'.
+//         this.x = 1,
+//                ^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:56:16: Error: Can't have initializers after 'super'.
+//         this.y = 2;
+//                ^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:58:16: Error: A redirecting constructor can't have other initializers.
+//       : this.x = 1,
+//                ^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:59:16: Error: A redirecting constructor can't have other initializers.
+//         this.y = 2,
+//                ^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:62:9: Error: A redirecting constructor can't have other initializers.
+//       : assert(true),
+//         ^^^^^^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:66:9: Error: A redirecting constructor can't have other initializers.
+//         assert(true);
+//         ^^^^^^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:72:9: Error: A redirecting constructor can't have a 'super' initializer.
+//         super() {}
+//         ^^^^^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:78:9: Error: A redirecting constructor can't have a 'super' initializer.
+//       : super(),
+//         ^^^^^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:80:9: Error: Can't have more than one 'super' initializer.
+//         super() {}
+//         ^^^^^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:87:14: Error: A redirecting constructor can't have more than one redirection.
+//         this.named();
+//              ^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:94:9: Error: Can't have more than one 'super' initializer.
+//         super() {}
+//         ^^^^^
+//
+// pkg/front_end/testcases/general/initialzation_errors.dart:101:16: Error: Can't have initializers after 'super'.
+//         this.x = 42 {}
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* x;
+  constructor •() → self::A*
+    : self::A::x = 41, final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:9:16: Error: 'x' was already initialized by this constructor.
+        this.x = 42 {}
+               ^", super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  final field core::int* x;
+  constructor •() → self::B*
+    : self::B::x = 41, final dynamic #t2 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:16:16: Error: 'x' was already initialized by this constructor.
+        this.x = 42 {}
+               ^", super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  final field core::int* x = 2;
+  constructor •() → self::C*
+    : final dynamic #t3 = throw new core::_DuplicatedFieldInitializerError::•("x"), final dynamic #t4 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:23:16: Error: 'x' was already initialized by this constructor.
+        this.x = 42 {}
+               ^", super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends core::Object {
+  final field core::int* x;
+  final field core::int* y;
+  constructor •() → self::D*
+    : final dynamic #t5 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:30:16: Error: A redirecting constructor can't have other initializers.
+      : this.x = 41,
+               ^", final dynamic #t6 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:32:16: Error: A redirecting constructor can't have other initializers.
+        this.y = 42 {}
+               ^", this self::D::named() {}
+  constructor named() → self::D*
+    : self::D::x = 41, self::D::y = 42, super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E extends core::Object {
+  final field core::int* x;
+  final field core::int* y;
+  constructor •() → self::E*
+    : final dynamic #t7 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:43:16: Error: A redirecting constructor can't have other initializers.
+        this.x = 1,
+               ^", final dynamic #t8 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:44:16: Error: A redirecting constructor can't have other initializers.
+        this.y = 2 {}
+               ^", this self::E::named() {}
+  constructor named() → self::E*
+    : self::E::x = 41, self::E::y = 42, super core::Object::•() {}
+  constructor named2() → self::E*
+    : final dynamic #t9 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:49:16: Error: A redirecting constructor can't have other initializers.
+      : this.x = 1,
+               ^", final dynamic #t10 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:51:16: Error: A redirecting constructor can't have other initializers.
+        this.y = 2;
+               ^", this self::E::named()
+    ;
+  constructor named3() → self::E*
+    : final dynamic #t11 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:53:9: Error: A redirecting constructor can't have a 'super' initializer.
+      : super(),
+        ^^^^^", final dynamic #t12 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:55:16: Error: Can't have initializers after 'super'.
+        this.x = 1,
+               ^", final dynamic #t13 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:56:16: Error: Can't have initializers after 'super'.
+        this.y = 2;
+               ^", super core::Object::•()
+    ;
+  constructor named4() → self::E*
+    : final dynamic #t14 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:58:16: Error: A redirecting constructor can't have other initializers.
+      : this.x = 1,
+               ^", final dynamic #t15 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:59:16: Error: A redirecting constructor can't have other initializers.
+        this.y = 2,
+               ^", this self::E::named()
+    ;
+  constructor named5() → self::E*
+    : final dynamic #t16 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:62:9: Error: A redirecting constructor can't have other initializers.
+      : assert(true),
+        ^^^^^^", this self::E::named()
+    ;
+  constructor named6() → self::E*
+    : final dynamic #t17 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:66:9: Error: A redirecting constructor can't have other initializers.
+        assert(true);
+        ^^^^^^", this self::E::named()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F extends core::Object {
+  constructor •() → self::F*
+    : final dynamic #t18 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:72:9: Error: A redirecting constructor can't have a 'super' initializer.
+        super() {}
+        ^^^^^", this self::F::named() {}
+  constructor named() → self::F*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class G extends core::Object {
+  constructor •() → self::G*
+    : final dynamic #t19 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:78:9: Error: A redirecting constructor can't have a 'super' initializer.
+      : super(),
+        ^^^^^", final dynamic #t20 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:80:9: Error: Can't have more than one 'super' initializer.
+        super() {}
+        ^^^^^", super core::Object::•() {}
+  constructor named() → self::G*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class H extends core::Object {
+  constructor •() → self::H*
+    : final dynamic #t21 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:87:14: Error: A redirecting constructor can't have more than one redirection.
+        this.named();
+             ^", this self::H::named()
+    ;
+  constructor named() → self::H*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class I extends core::Object {
+  constructor •() → self::I*
+    : final dynamic #t22 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:94:9: Error: Can't have more than one 'super' initializer.
+        super() {}
+        ^^^^^", super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class J extends core::Object {
+  field core::int* x;
+  constructor •() → self::J*
+    : final dynamic #t23 = invalid-expression "pkg/front_end/testcases/general/initialzation_errors.dart:101:16: Error: Can't have initializers after 'super'.
+        this.x = 42 {}
+               ^", super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/instance_setter_conflict.dart.weak.modular.expect b/pkg/front_end/testcases/general/instance_setter_conflict.dart.weak.modular.expect
new file mode 100644
index 0000000..22c9052
--- /dev/null
+++ b/pkg/front_end/testcases/general/instance_setter_conflict.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/instance_setter_conflict.dart:11:14: Error: Can't declare a member that conflicts with an inherited one.
+//   static get v {
+//              ^
+// pkg/front_end/testcases/general/instance_setter_conflict.dart:6:7: Context: This is the inherited member.
+//   int v;
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* v = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::A {
+  static field core::int* n = null;
+  synthetic constructor •() → self::C*
+    : super self::A::•()
+    ;
+  static get v() → dynamic {
+    return self::C::n;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/interface_conflict.dart.weak.modular.expect b/pkg/front_end/testcases/general/interface_conflict.dart.weak.modular.expect
new file mode 100644
index 0000000..35d40fb
--- /dev/null
+++ b/pkg/front_end/testcases/general/interface_conflict.dart.weak.modular.expect
@@ -0,0 +1,83 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/interface_conflict.dart:13:16: Error: Class 'C' inherits multiple members named 'n' with incompatible signatures.
+// Try adding a declaration of 'n' to 'C'.
+// abstract class C implements A, B {}
+//                ^
+// pkg/front_end/testcases/general/interface_conflict.dart:6:11: Context: This is one of the overridden members.
+//   int get n => 1;
+//           ^
+// pkg/front_end/testcases/general/interface_conflict.dart:10:14: Context: This is one of the overridden members.
+//   double get n => 2.0;
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  get n() → core::int*
+    return 1;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  get n() → core::double*
+    return 2.0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object implements self::A, self::B {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D extends core::Object implements self::C {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/interface_contravariant_from_class.dart.weak.modular.expect b/pkg/front_end/testcases/general/interface_contravariant_from_class.dart.weak.modular.expect
new file mode 100644
index 0000000..a99ce5f
--- /dev/null
+++ b/pkg/front_end/testcases/general/interface_contravariant_from_class.dart.weak.modular.expect
@@ -0,0 +1,64 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/interface_contravariant_from_class.dart:17:16: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'B'.
+// abstract class C<T> extends B<F<T>> implements I<F<T>> {}
+//                ^
+//
+// pkg/front_end/testcases/general/interface_contravariant_from_class.dart:17:16: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'I'.
+// abstract class C<T> extends B<F<T>> implements I<F<T>> {}
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+class B<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  method f(core::int* x) → self::B::T* {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::T*>*
+    : super core::Object::•()
+    ;
+  abstract method f(core::Object* x) → self::I::T*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/general/interface_covariantImpl_from_class.dart.weak.modular.expect b/pkg/front_end/testcases/general/interface_covariantImpl_from_class.dart.weak.modular.expect
new file mode 100644
index 0000000..5ba8fab
--- /dev/null
+++ b/pkg/front_end/testcases/general/interface_covariantImpl_from_class.dart.weak.modular.expect
@@ -0,0 +1,64 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/interface_covariantImpl_from_class.dart:17:16: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'B'.
+// abstract class C<T> extends B<F<T>> implements I<F<T>> {}
+//                ^
+//
+// pkg/front_end/testcases/general/interface_covariantImpl_from_class.dart:17:16: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'I'.
+// abstract class C<T> extends B<F<T>> implements I<F<T>> {}
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+class B<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  method f((self::B::T*) →* void x, core::int* y) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::T*>*
+    : super core::Object::•()
+    ;
+  abstract method f((self::I::T*) →* void x, core::Object* y) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/general/interface_covariantInterface_from_class.dart.weak.modular.expect b/pkg/front_end/testcases/general/interface_covariantInterface_from_class.dart.weak.modular.expect
new file mode 100644
index 0000000..68f6ac0
--- /dev/null
+++ b/pkg/front_end/testcases/general/interface_covariantInterface_from_class.dart.weak.modular.expect
@@ -0,0 +1,88 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/interface_covariantInterface_from_class.dart:13:7: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// class B<T> implements A<F<T>> {
+//       ^
+//
+// pkg/front_end/testcases/general/interface_covariantInterface_from_class.dart:17:16: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'A'.
+// abstract class I<T> implements A<F<T>> {
+//                ^
+//
+// pkg/front_end/testcases/general/interface_covariantInterface_from_class.dart:21:16: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'B'.
+// abstract class C<T> extends B<F<T>> implements I<F<T>> {}
+//                ^
+//
+// pkg/front_end/testcases/general/interface_covariantInterface_from_class.dart:21:16: Error: Can't use implicitly 'out' variable 'T' in an 'in' position in supertype 'I'.
+// abstract class C<T> extends B<F<T>> implements I<F<T>> {}
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+abstract class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract method f(covariant-by-class self::A::T* x, core::int* y) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  method f((self::B::T*) →* void x, core::int* y) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::T*>*
+    : super core::Object::•()
+    ;
+  abstract method f((self::I::T*) →* void x, core::Object* y) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/general/invalid_assignment.dart.weak.modular.expect b/pkg/front_end/testcases/general/invalid_assignment.dart.weak.modular.expect
new file mode 100644
index 0000000..a16acb5
--- /dev/null
+++ b/pkg/front_end/testcases/general/invalid_assignment.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/invalid_assignment.dart:11:7: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   i = s;
+//       ^
+//
+// pkg/front_end/testcases/general/invalid_assignment.dart:13:9: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   i ??= s;
+//         ^
+//
+// pkg/front_end/testcases/general/invalid_assignment.dart:15:5: Error: A value of type 'String' can't be assigned to a variable of type 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/general/invalid_assignment.dart'.
+//   a += 1;
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator +(core::int* i) → core::String*
+    return "";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test(core::int* i, core::String* s, self::A* a) → dynamic {
+  i = 1;
+  i = invalid-expression "pkg/front_end/testcases/general/invalid_assignment.dart:11:7: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  i = s;
+      ^" in s as{TypeError} core::int*;
+  i == null ?{core::int*} i = 1 : null;
+  i == null ?{core::Object*} i = invalid-expression "pkg/front_end/testcases/general/invalid_assignment.dart:13:9: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  i ??= s;
+        ^" in s as{TypeError} core::int* : null;
+  a = new self::A::•();
+  a = invalid-expression "pkg/front_end/testcases/general/invalid_assignment.dart:15:5: Error: A value of type 'String' can't be assigned to a variable of type 'A'.
+ - 'A' is from 'pkg/front_end/testcases/general/invalid_assignment.dart'.
+  a += 1;
+    ^" in a.{self::A::+}(1){(core::int*) →* core::String*} as{TypeError} self::A*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/invalid_cast.dart.weak.modular.expect b/pkg/front_end/testcases/general/invalid_cast.dart.weak.modular.expect
new file mode 100644
index 0000000..6d764be
--- /dev/null
+++ b/pkg/front_end/testcases/general/invalid_cast.dart.weak.modular.expect
@@ -0,0 +1,175 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/invalid_cast.dart:22:25: Error: The list literal type 'List<Object>' isn't of expected type 'List<int>'.
+//  - 'List' is from 'dart:core'.
+//  - 'Object' is from 'dart:core'.
+// Change the type of the list literal or the context in which it is used.
+//   List<int> a = <Object>[];
+//                         ^
+//
+// pkg/front_end/testcases/general/invalid_cast.dart:23:40: Error: The map literal type 'Map<Object, String>' isn't of expected type 'Map<int, String>'.
+//  - 'Map' is from 'dart:core'.
+//  - 'Object' is from 'dart:core'.
+// Change the type of the map literal or the context in which it is used.
+//   Map<int, String> b = <Object, String>{};
+//                                        ^
+//
+// pkg/front_end/testcases/general/invalid_cast.dart:24:37: Error: The map literal type 'Map<int, Object>' isn't of expected type 'Map<int, String>'.
+//  - 'Map' is from 'dart:core'.
+//  - 'Object' is from 'dart:core'.
+// Change the type of the map literal or the context in which it is used.
+//   Map<int, String> c = <int, Object>{};
+//                                     ^
+//
+// pkg/front_end/testcases/general/invalid_cast.dart:25:28: Error: The function expression type 'int Function(int)' isn't of expected type 'int Function(Object)'.
+//  - 'Object' is from 'dart:core'.
+// Change the type of the function expression or the context in which it is used.
+//   int Function(Object) d = (int i) => i;
+//                            ^
+//
+// pkg/front_end/testcases/general/invalid_cast.dart:28:13: Error: The constructor returns type 'C' that isn't of expected type 'D'.
+//  - 'C' is from 'pkg/front_end/testcases/general/invalid_cast.dart'.
+//  - 'D' is from 'pkg/front_end/testcases/general/invalid_cast.dart'.
+// Change the type of the object being constructed or the context in which it is used.
+//   D g = new C.nonFact();
+//             ^
+//
+// pkg/front_end/testcases/general/invalid_cast.dart:29:13: Error: The constructor returns type 'C' that isn't of expected type 'D'.
+//  - 'C' is from 'pkg/front_end/testcases/general/invalid_cast.dart'.
+//  - 'D' is from 'pkg/front_end/testcases/general/invalid_cast.dart'.
+// Change the type of the object being constructed or the context in which it is used.
+//   D h = new C.nonFact2();
+//             ^
+//
+// pkg/front_end/testcases/general/invalid_cast.dart:30:31: Error: The static method has type 'void Function(int)' that isn't of expected type 'void Function(Object)'.
+//  - 'Object' is from 'dart:core'.
+// Change the type of the method or the context in which it is used.
+//   void Function(Object) i = C.staticFunction;
+//                               ^
+//
+// pkg/front_end/testcases/general/invalid_cast.dart:31:29: Error: The top level function has type 'void Function(int)' that isn't of expected type 'void Function(Object)'.
+//  - 'Object' is from 'dart:core'.
+// Change the type of the function or the context in which it is used.
+//   void Function(Object) j = topLevelFunction;
+//                             ^
+//
+// pkg/front_end/testcases/general/invalid_cast.dart:32:29: Error: The local function has type 'void Function(int)' that isn't of expected type 'void Function(Object)'.
+//  - 'Object' is from 'dart:core'.
+// Change the type of the function or the context in which it is used.
+//   void Function(Object) k = localFunction;
+//                             ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  constructor nonFact() → self::C*
+    : super core::Object::•()
+    ;
+  constructor nonFact2() → self::C*
+    : this self::C::nonFact()
+    ;
+  static factory fact() → self::C*
+    return null;
+  static factory fact2() → self::C*
+    return new self::D::•();
+  static method staticFunction(core::int* i) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+}
+static method topLevelFunction(core::int* i) → void {}
+static method bad() → dynamic {
+  function localFunction(core::int* i) → void {}
+  core::List<core::int*>* a = invalid-expression "pkg/front_end/testcases/general/invalid_cast.dart:22:25: Error: The list literal type 'List<Object>' isn't of expected type 'List<int>'.
+ - 'List' is from 'dart:core'.
+ - 'Object' is from 'dart:core'.
+Change the type of the list literal or the context in which it is used.
+  List<int> a = <Object>[];
+                        ^" in <core::Object*>[];
+  core::Map<core::int*, core::String*>* b = invalid-expression "pkg/front_end/testcases/general/invalid_cast.dart:23:40: Error: The map literal type 'Map<Object, String>' isn't of expected type 'Map<int, String>'.
+ - 'Map' is from 'dart:core'.
+ - 'Object' is from 'dart:core'.
+Change the type of the map literal or the context in which it is used.
+  Map<int, String> b = <Object, String>{};
+                                       ^" in <core::Object*, core::String*>{};
+  core::Map<core::int*, core::String*>* c = invalid-expression "pkg/front_end/testcases/general/invalid_cast.dart:24:37: Error: The map literal type 'Map<int, Object>' isn't of expected type 'Map<int, String>'.
+ - 'Map' is from 'dart:core'.
+ - 'Object' is from 'dart:core'.
+Change the type of the map literal or the context in which it is used.
+  Map<int, String> c = <int, Object>{};
+                                    ^" in <core::int*, core::Object*>{};
+  (core::Object*) →* core::int* d = invalid-expression "pkg/front_end/testcases/general/invalid_cast.dart:25:28: Error: The function expression type 'int Function(int)' isn't of expected type 'int Function(Object)'.
+ - 'Object' is from 'dart:core'.
+Change the type of the function expression or the context in which it is used.
+  int Function(Object) d = (int i) => i;
+                           ^" in (core::int* i) → core::int* => i;
+  self::D* e = self::C::fact() as{TypeError} self::D*;
+  self::D* f = new self::D::•() as{TypeError} self::D*;
+  self::D* g = invalid-expression "pkg/front_end/testcases/general/invalid_cast.dart:28:13: Error: The constructor returns type 'C' that isn't of expected type 'D'.
+ - 'C' is from 'pkg/front_end/testcases/general/invalid_cast.dart'.
+ - 'D' is from 'pkg/front_end/testcases/general/invalid_cast.dart'.
+Change the type of the object being constructed or the context in which it is used.
+  D g = new C.nonFact();
+            ^" in new self::C::nonFact();
+  self::D* h = invalid-expression "pkg/front_end/testcases/general/invalid_cast.dart:29:13: Error: The constructor returns type 'C' that isn't of expected type 'D'.
+ - 'C' is from 'pkg/front_end/testcases/general/invalid_cast.dart'.
+ - 'D' is from 'pkg/front_end/testcases/general/invalid_cast.dart'.
+Change the type of the object being constructed or the context in which it is used.
+  D h = new C.nonFact2();
+            ^" in new self::C::nonFact2();
+  (core::Object*) →* void i = invalid-expression "pkg/front_end/testcases/general/invalid_cast.dart:30:31: Error: The static method has type 'void Function(int)' that isn't of expected type 'void Function(Object)'.
+ - 'Object' is from 'dart:core'.
+Change the type of the method or the context in which it is used.
+  void Function(Object) i = C.staticFunction;
+                              ^" in #C2;
+  (core::Object*) →* void j = invalid-expression "pkg/front_end/testcases/general/invalid_cast.dart:31:29: Error: The top level function has type 'void Function(int)' that isn't of expected type 'void Function(Object)'.
+ - 'Object' is from 'dart:core'.
+Change the type of the function or the context in which it is used.
+  void Function(Object) j = topLevelFunction;
+                            ^" in #C3;
+  (core::Object*) →* void k = invalid-expression "pkg/front_end/testcases/general/invalid_cast.dart:32:29: Error: The local function has type 'void Function(int)' that isn't of expected type 'void Function(Object)'.
+ - 'Object' is from 'dart:core'.
+Change the type of the function or the context in which it is used.
+  void Function(Object) k = localFunction;
+                            ^" in localFunction;
+}
+static method ok() → dynamic {
+  function localFunction(core::int* i) → void {}
+  core::List<core::int*>* a = <core::int*>[];
+  core::Map<core::int*, core::String*>* b = <core::int*, core::String*>{};
+  core::Map<core::int*, core::String*>* c = <core::int*, core::String*>{};
+  (core::int*) →* core::int* d = (core::int* i) → core::int* => i;
+  self::D* e = self::C::fact() as{TypeError} self::D*;
+  self::D* f = new self::D::•() as{TypeError} self::D*;
+  self::C* g = new self::C::nonFact();
+  self::C* h = new self::C::nonFact2();
+  (core::int*) →* void i = #C2;
+  (core::int*) →* void j = #C3;
+  (core::int*) →* void k = localFunction;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::C::fact2
+  #C2 = static-tearoff self::C::staticFunction
+  #C3 = static-tearoff self::topLevelFunction
+}
diff --git a/pkg/front_end/testcases/general/invalid_for_in_iterable.dart.weak.modular.expect b/pkg/front_end/testcases/general/invalid_for_in_iterable.dart.weak.modular.expect
new file mode 100644
index 0000000..bf9baa8
--- /dev/null
+++ b/pkg/front_end/testcases/general/invalid_for_in_iterable.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/invalid_for_in_iterable.dart:14:27: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//   for (var v in takesNoArg(0)) {}
+//                           ^
+// pkg/front_end/testcases/general/invalid_for_in_iterable.dart:7:10: Context: Found this candidate, but the arguments don't match.
+// Iterable takesNoArg() => null;
+//          ^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/invalid_for_in_iterable.dart:15:17: Error: This expression has type 'void' and can't be used.
+//   for (var v in returnVoid()) {}
+//                 ^
+//
+// pkg/front_end/testcases/general/invalid_for_in_iterable.dart:16:17: Error: The type 'int' used in the 'for' loop must implement 'Iterable<dynamic>'.
+//  - 'Iterable' is from 'dart:core'.
+//   for (var v in returnInt()) {}
+//                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method takesNoArg() → core::Iterable<dynamic>*
+  return null;
+static method returnVoid() → void {}
+static method returnInt() → core::int*
+  return 42;
+static method returnDynamic() → dynamic
+  return <dynamic>[];
+static method returnObject() → core::Object*
+  return 0;
+static method test() → dynamic {
+  for (dynamic v in invalid-expression "pkg/front_end/testcases/general/invalid_for_in_iterable.dart:14:27: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+  for (var v in takesNoArg(0)) {}
+                          ^") {
+  }
+  for (dynamic v in invalid-expression "pkg/front_end/testcases/general/invalid_for_in_iterable.dart:15:17: Error: This expression has type 'void' and can't be used.
+  for (var v in returnVoid()) {}
+                ^" in self::returnVoid()) {
+  }
+  for (dynamic v in invalid-expression "pkg/front_end/testcases/general/invalid_for_in_iterable.dart:16:17: Error: The type 'int' used in the 'for' loop must implement 'Iterable<dynamic>'.
+ - 'Iterable' is from 'dart:core'.
+  for (var v in returnInt()) {}
+                ^" in self::returnInt() as{TypeError} core::Iterable<dynamic>*) {
+  }
+  for (dynamic v in self::returnDynamic() as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+  }
+  for (dynamic v in self::returnObject() as{TypeError} core::Iterable<dynamic>*) {
+  }
+  for (dynamic v in throw "") {
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/invalid_operator.dart.weak.expect b/pkg/front_end/testcases/general/invalid_operator.dart.weak.expect
index c3f1e06..1bababf 100644
--- a/pkg/front_end/testcases/general/invalid_operator.dart.weak.expect
+++ b/pkg/front_end/testcases/general/invalid_operator.dart.weak.expect
@@ -564,35 +564,35 @@
 // Try adding explicit types.
 //   operator ==<T>(a) => true;
 //            ^^
-// sdk/lib/_internal/vm/lib/object_patch.dart:29:26: Context: This is one of the overridden members.
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is one of the overridden members.
 //   external bool operator ==(Object other);
 //                          ^^
 //
 // pkg/front_end/testcases/general/invalid_operator.dart:6:12: Error: The method 'Operators1.==' has fewer positional arguments than those of overridden method 'Object.=='.
 //   operator ==() => true;
 //            ^
-// sdk/lib/_internal/vm/lib/object_patch.dart:29:26: Context: This is the overridden method ('==').
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
 //   external bool operator ==(Object other);
 //                          ^
 //
 // pkg/front_end/testcases/general/invalid_operator.dart:27:12: Error: The method 'Operators2.==' has more required arguments than those of overridden method 'Object.=='.
 //   operator ==(a, b) => true;
 //            ^
-// sdk/lib/_internal/vm/lib/object_patch.dart:29:26: Context: This is the overridden method ('==').
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
 //   external bool operator ==(Object other);
 //                          ^
 //
 // pkg/front_end/testcases/general/invalid_operator.dart:71:12: Error: The method 'Operators4.==' has fewer positional arguments than those of overridden method 'Object.=='.
 //   operator ==({a}) => true;
 //            ^
-// sdk/lib/_internal/vm/lib/object_patch.dart:29:26: Context: This is the overridden method ('==').
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
 //   external bool operator ==(Object other);
 //                          ^
 //
 // pkg/front_end/testcases/general/invalid_operator.dart:137:12: Error: Declared type variables of 'Operators7.==' doesn't match those on overridden method 'Object.=='.
 //   operator ==<T>(a) => true;
 //            ^
-// sdk/lib/_internal/vm/lib/object_patch.dart:29:26: Context: This is the overridden method ('==').
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
 //   external bool operator ==(Object other);
 //                          ^
 //
diff --git a/pkg/front_end/testcases/general/invalid_operator.dart.weak.modular.expect b/pkg/front_end/testcases/general/invalid_operator.dart.weak.modular.expect
new file mode 100644
index 0000000..1bababf
--- /dev/null
+++ b/pkg/front_end/testcases/general/invalid_operator.dart.weak.modular.expect
@@ -0,0 +1,968 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:6:12: Error: Operator '==' should have exactly one parameter.
+//   operator ==() => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:7:12: Error: Operator '<' should have exactly one parameter.
+//   operator <() => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:8:12: Error: Operator '>' should have exactly one parameter.
+//   operator >() => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:9:12: Error: Operator '<=' should have exactly one parameter.
+//   operator <=() => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:10:12: Error: Operator '>=' should have exactly one parameter.
+//   operator >=() => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:11:12: Error: Operator '+' should have exactly one parameter.
+//   operator +() => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:12:12: Error: Operator '/' should have exactly one parameter.
+//   operator /() => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:13:12: Error: Operator '~/' should have exactly one parameter.
+//   operator ~/() => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:14:12: Error: Operator '*' should have exactly one parameter.
+//   operator *() => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:15:12: Error: Operator '%' should have exactly one parameter.
+//   operator %() => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:16:12: Error: Operator '|' should have exactly one parameter.
+//   operator |() => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:17:12: Error: Operator '^' should have exactly one parameter.
+//   operator ^() => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:18:12: Error: Operator '&' should have exactly one parameter.
+//   operator &() => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:19:12: Error: Operator '<<' should have exactly one parameter.
+//   operator <<() => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:20:12: Error: Operator '>>' should have exactly one parameter.
+//   operator >>() => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:21:12: Error: Operator '[]=' should have exactly two parameters.
+//   operator []=(a, b, c) => true;
+//            ^^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:22:12: Error: Operator '[]' should have exactly one parameter.
+//   operator []() => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:23:12: Error: Operator '~' shouldn't have any parameters.
+//   operator ~(a) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:27:12: Error: Operator '==' should have exactly one parameter.
+//   operator ==(a, b) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:28:12: Error: Operator '<' should have exactly one parameter.
+//   operator <(a, b) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:29:12: Error: Operator '>' should have exactly one parameter.
+//   operator >(a, b) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:30:12: Error: Operator '<=' should have exactly one parameter.
+//   operator <=(a, b) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:31:12: Error: Operator '>=' should have exactly one parameter.
+//   operator >=(a, b) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:32:12: Error: Operator '-' should have zero or one parameter.
+// With zero parameters, it has the syntactic form '-a', formally known as 'unary-'. With one parameter, it has the syntactic form 'a - b', formally known as '-'.
+//   operator -(a, b) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:33:12: Error: Operator '+' should have exactly one parameter.
+//   operator +(a, b) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:34:12: Error: Operator '/' should have exactly one parameter.
+//   operator /(a, b) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:35:12: Error: Operator '~/' should have exactly one parameter.
+//   operator ~/(a, b) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:36:12: Error: Operator '*' should have exactly one parameter.
+//   operator *(a, b) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:37:12: Error: Operator '%' should have exactly one parameter.
+//   operator %(a, b) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:38:12: Error: Operator '|' should have exactly one parameter.
+//   operator |(a, b) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:39:12: Error: Operator '^' should have exactly one parameter.
+//   operator ^(a, b) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:40:12: Error: Operator '&' should have exactly one parameter.
+//   operator &(a, b) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:41:12: Error: Operator '<<' should have exactly one parameter.
+//   operator <<(a, b) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:42:12: Error: Operator '>>' should have exactly one parameter.
+//   operator >>(a, b) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:43:12: Error: Operator '[]=' should have exactly two parameters.
+//   operator []=(a, b, c) => true;
+//            ^^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:44:12: Error: Operator '[]' should have exactly one parameter.
+//   operator [](a, b) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:45:12: Error: Operator '~' shouldn't have any parameters.
+//   operator ~(a, b) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:49:16: Error: An operator can't have optional parameters.
+//   operator ==([a]) => true;
+//                ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:50:15: Error: An operator can't have optional parameters.
+//   operator <([a]) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:51:15: Error: An operator can't have optional parameters.
+//   operator >([a]) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:52:16: Error: An operator can't have optional parameters.
+//   operator <=([a]) => true;
+//                ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:53:16: Error: An operator can't have optional parameters.
+//   operator >=([a]) => true;
+//                ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:54:15: Error: An operator can't have optional parameters.
+//   operator -([a]) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:55:15: Error: An operator can't have optional parameters.
+//   operator +([a]) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:56:15: Error: An operator can't have optional parameters.
+//   operator /([a]) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:57:16: Error: An operator can't have optional parameters.
+//   operator ~/([a]) => true;
+//                ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:58:15: Error: An operator can't have optional parameters.
+//   operator *([a]) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:59:15: Error: An operator can't have optional parameters.
+//   operator %([a]) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:60:15: Error: An operator can't have optional parameters.
+//   operator |([a]) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:61:15: Error: An operator can't have optional parameters.
+//   operator ^([a]) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:62:15: Error: An operator can't have optional parameters.
+//   operator &([a]) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:63:16: Error: An operator can't have optional parameters.
+//   operator <<([a]) => true;
+//                ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:64:16: Error: An operator can't have optional parameters.
+//   operator >>([a]) => true;
+//                ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:65:17: Error: An operator can't have optional parameters.
+//   operator []=([a, b]) => true;
+//                 ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:65:20: Error: An operator can't have optional parameters.
+//   operator []=([a, b]) => true;
+//                    ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:66:16: Error: An operator can't have optional parameters.
+//   operator []([a]) => true;
+//                ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:67:12: Error: Operator '~' shouldn't have any parameters.
+//   operator ~([a]) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:71:16: Error: An operator can't have optional parameters.
+//   operator ==({a}) => true;
+//                ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:72:15: Error: An operator can't have optional parameters.
+//   operator <({a}) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:73:15: Error: An operator can't have optional parameters.
+//   operator >({a}) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:74:16: Error: An operator can't have optional parameters.
+//   operator <=({a}) => true;
+//                ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:75:16: Error: An operator can't have optional parameters.
+//   operator >=({a}) => true;
+//                ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:76:15: Error: An operator can't have optional parameters.
+//   operator -({a}) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:77:15: Error: An operator can't have optional parameters.
+//   operator +({a}) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:78:15: Error: An operator can't have optional parameters.
+//   operator /({a}) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:79:16: Error: An operator can't have optional parameters.
+//   operator ~/({a}) => true;
+//                ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:80:15: Error: An operator can't have optional parameters.
+//   operator *({a}) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:81:15: Error: An operator can't have optional parameters.
+//   operator %({a}) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:82:15: Error: An operator can't have optional parameters.
+//   operator |({a}) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:83:15: Error: An operator can't have optional parameters.
+//   operator ^({a}) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:84:15: Error: An operator can't have optional parameters.
+//   operator &({a}) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:85:16: Error: An operator can't have optional parameters.
+//   operator <<({a}) => true;
+//                ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:86:16: Error: An operator can't have optional parameters.
+//   operator >>({a}) => true;
+//                ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:87:17: Error: An operator can't have optional parameters.
+//   operator []=({a, b}) => true;
+//                 ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:87:20: Error: An operator can't have optional parameters.
+//   operator []=({a, b}) => true;
+//                    ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:88:16: Error: An operator can't have optional parameters.
+//   operator []({a}) => true;
+//                ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:89:12: Error: Operator '~' shouldn't have any parameters.
+//   operator ~({a}) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:93:12: Error: Operator '==' should have exactly one parameter.
+//   operator ==(a, [b]) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:94:12: Error: Operator '<' should have exactly one parameter.
+//   operator <(a, [b]) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:95:12: Error: Operator '>' should have exactly one parameter.
+//   operator >(a, [b]) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:96:12: Error: Operator '<=' should have exactly one parameter.
+//   operator <=(a, [b]) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:97:12: Error: Operator '>=' should have exactly one parameter.
+//   operator >=(a, [b]) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:98:12: Error: Operator '-' should have zero or one parameter.
+// With zero parameters, it has the syntactic form '-a', formally known as 'unary-'. With one parameter, it has the syntactic form 'a - b', formally known as '-'.
+//   operator -(a, [b]) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:99:12: Error: Operator '+' should have exactly one parameter.
+//   operator +(a, [b]) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:100:12: Error: Operator '/' should have exactly one parameter.
+//   operator /(a, [b]) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:101:12: Error: Operator '~/' should have exactly one parameter.
+//   operator ~/(a, [b]) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:102:12: Error: Operator '*' should have exactly one parameter.
+//   operator *(a, [b]) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:103:12: Error: Operator '%' should have exactly one parameter.
+//   operator %(a, [b]) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:104:12: Error: Operator '|' should have exactly one parameter.
+//   operator |(a, [b]) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:105:12: Error: Operator '^' should have exactly one parameter.
+//   operator ^(a, [b]) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:106:12: Error: Operator '&' should have exactly one parameter.
+//   operator &(a, [b]) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:107:12: Error: Operator '<<' should have exactly one parameter.
+//   operator <<(a, [b]) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:108:12: Error: Operator '>>' should have exactly one parameter.
+//   operator >>(a, [b]) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:109:12: Error: Operator '[]=' should have exactly two parameters.
+//   operator []=(a, b, [c]) => true;
+//            ^^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:110:12: Error: Operator '[]' should have exactly one parameter.
+//   operator [](a, [b]) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:111:12: Error: Operator '~' shouldn't have any parameters.
+//   operator ~(a, [b]) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:115:12: Error: Operator '==' should have exactly one parameter.
+//   operator ==(a, {b}) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:116:12: Error: Operator '<' should have exactly one parameter.
+//   operator <(a, {b}) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:117:12: Error: Operator '>' should have exactly one parameter.
+//   operator >(a, {b}) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:118:12: Error: Operator '<=' should have exactly one parameter.
+//   operator <=(a, {b}) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:119:12: Error: Operator '>=' should have exactly one parameter.
+//   operator >=(a, {b}) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:120:12: Error: Operator '-' should have zero or one parameter.
+// With zero parameters, it has the syntactic form '-a', formally known as 'unary-'. With one parameter, it has the syntactic form 'a - b', formally known as '-'.
+//   operator -(a, {b}) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:121:12: Error: Operator '+' should have exactly one parameter.
+//   operator +(a, {b}) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:122:12: Error: Operator '/' should have exactly one parameter.
+//   operator /(a, {b}) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:123:12: Error: Operator '~/' should have exactly one parameter.
+//   operator ~/(a, {b}) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:124:12: Error: Operator '*' should have exactly one parameter.
+//   operator *(a, {b}) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:125:12: Error: Operator '%' should have exactly one parameter.
+//   operator %(a, {b}) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:126:12: Error: Operator '|' should have exactly one parameter.
+//   operator |(a, {b}) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:127:12: Error: Operator '^' should have exactly one parameter.
+//   operator ^(a, {b}) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:128:12: Error: Operator '&' should have exactly one parameter.
+//   operator &(a, {b}) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:129:12: Error: Operator '<<' should have exactly one parameter.
+//   operator <<(a, {b}) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:130:12: Error: Operator '>>' should have exactly one parameter.
+//   operator >>(a, {b}) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:131:12: Error: Operator '[]=' should have exactly two parameters.
+//   operator []=(a, b, {c}) => true;
+//            ^^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:132:12: Error: Operator '[]' should have exactly one parameter.
+//   operator [](a, {b}) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:133:12: Error: Operator '~' shouldn't have any parameters.
+//   operator ~(a, {b}) => true;
+//            ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:137:15: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator ==<T>(a) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:138:14: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator ><T>(a) => true;
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:139:15: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator <=<T>(a) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:140:15: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator >=<T>(a) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:141:14: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator -<T>() => true;
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:142:14: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator -<T>(a) => true;
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:143:14: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator +<T>(a) => true;
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:144:14: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator /<T>(a) => true;
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:145:15: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator ~/<T>(a) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:146:14: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator *<T>(a) => true;
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:147:14: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator %<T>(a) => true;
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:148:14: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator |<T>(a) => true;
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:149:14: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator ^<T>(a) => true;
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:150:14: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator &<T>(a) => true;
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:151:15: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator <<<T>(a) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:152:15: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator >><T>(a) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:153:16: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator []=<T>(a, b) => true;
+//                ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:154:15: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator []<T>(a) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:155:14: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator ~<T>() => true;
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:137:12: Error: Can't infer types for '==' as the overridden members don't have a combined signature.
+// Try adding explicit types.
+//   operator ==<T>(a) => true;
+//            ^^
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is one of the overridden members.
+//   external bool operator ==(Object other);
+//                          ^^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:6:12: Error: The method 'Operators1.==' has fewer positional arguments than those of overridden method 'Object.=='.
+//   operator ==() => true;
+//            ^
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
+//   external bool operator ==(Object other);
+//                          ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:27:12: Error: The method 'Operators2.==' has more required arguments than those of overridden method 'Object.=='.
+//   operator ==(a, b) => true;
+//            ^
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
+//   external bool operator ==(Object other);
+//                          ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:71:12: Error: The method 'Operators4.==' has fewer positional arguments than those of overridden method 'Object.=='.
+//   operator ==({a}) => true;
+//            ^
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
+//   external bool operator ==(Object other);
+//                          ^
+//
+// pkg/front_end/testcases/general/invalid_operator.dart:137:12: Error: Declared type variables of 'Operators7.==' doesn't match those on overridden method 'Object.=='.
+//   operator ==<T>(a) => true;
+//            ^
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
+//   external bool operator ==(Object other);
+//                          ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Operators1 extends core::Object {
+  synthetic constructor •() → self::Operators1*
+    : super core::Object::•()
+    ;
+  operator ==() → core::bool*
+    return true;
+  operator <() → dynamic
+    return true;
+  operator >() → dynamic
+    return true;
+  operator <=() → dynamic
+    return true;
+  operator >=() → dynamic
+    return true;
+  operator +() → dynamic
+    return true;
+  operator /() → dynamic
+    return true;
+  operator ~/() → dynamic
+    return true;
+  operator *() → dynamic
+    return true;
+  operator %() → dynamic
+    return true;
+  operator |() → dynamic
+    return true;
+  operator ^() → dynamic
+    return true;
+  operator &() → dynamic
+    return true;
+  operator <<() → dynamic
+    return true;
+  operator >>() → dynamic
+    return true;
+  operator []=(dynamic a, dynamic b, dynamic c) → void
+    return true;
+  operator []() → dynamic
+    return true;
+  operator ~(dynamic a) → dynamic
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Operators2 extends core::Object {
+  synthetic constructor •() → self::Operators2*
+    : super core::Object::•()
+    ;
+  operator ==(dynamic a, dynamic b) → core::bool*
+    return true;
+  operator <(dynamic a, dynamic b) → dynamic
+    return true;
+  operator >(dynamic a, dynamic b) → dynamic
+    return true;
+  operator <=(dynamic a, dynamic b) → dynamic
+    return true;
+  operator >=(dynamic a, dynamic b) → dynamic
+    return true;
+  operator -(dynamic a, dynamic b) → dynamic
+    return true;
+  operator +(dynamic a, dynamic b) → dynamic
+    return true;
+  operator /(dynamic a, dynamic b) → dynamic
+    return true;
+  operator ~/(dynamic a, dynamic b) → dynamic
+    return true;
+  operator *(dynamic a, dynamic b) → dynamic
+    return true;
+  operator %(dynamic a, dynamic b) → dynamic
+    return true;
+  operator |(dynamic a, dynamic b) → dynamic
+    return true;
+  operator ^(dynamic a, dynamic b) → dynamic
+    return true;
+  operator &(dynamic a, dynamic b) → dynamic
+    return true;
+  operator <<(dynamic a, dynamic b) → dynamic
+    return true;
+  operator >>(dynamic a, dynamic b) → dynamic
+    return true;
+  operator []=(dynamic a, dynamic b, dynamic c) → void
+    return true;
+  operator [](dynamic a, dynamic b) → dynamic
+    return true;
+  operator ~(dynamic a, dynamic b) → dynamic
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Operators3 extends core::Object {
+  synthetic constructor •() → self::Operators3*
+    : super core::Object::•()
+    ;
+  operator ==([dynamic a = #C1]) → core::bool*
+    return true;
+  operator <([dynamic a = #C1]) → dynamic
+    return true;
+  operator >([dynamic a = #C1]) → dynamic
+    return true;
+  operator <=([dynamic a = #C1]) → dynamic
+    return true;
+  operator >=([dynamic a = #C1]) → dynamic
+    return true;
+  operator -([dynamic a = #C1]) → dynamic
+    return true;
+  operator +([dynamic a = #C1]) → dynamic
+    return true;
+  operator /([dynamic a = #C1]) → dynamic
+    return true;
+  operator ~/([dynamic a = #C1]) → dynamic
+    return true;
+  operator *([dynamic a = #C1]) → dynamic
+    return true;
+  operator %([dynamic a = #C1]) → dynamic
+    return true;
+  operator |([dynamic a = #C1]) → dynamic
+    return true;
+  operator ^([dynamic a = #C1]) → dynamic
+    return true;
+  operator &([dynamic a = #C1]) → dynamic
+    return true;
+  operator <<([dynamic a = #C1]) → dynamic
+    return true;
+  operator >>([dynamic a = #C1]) → dynamic
+    return true;
+  operator []=([dynamic a = #C1, dynamic b = #C1]) → void
+    return true;
+  operator []([dynamic a = #C1]) → dynamic
+    return true;
+  operator ~([dynamic a = #C1]) → dynamic
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Operators4 extends core::Object {
+  synthetic constructor •() → self::Operators4*
+    : super core::Object::•()
+    ;
+  operator ==({dynamic a = #C1}) → core::bool*
+    return true;
+  operator <({dynamic a = #C1}) → dynamic
+    return true;
+  operator >({dynamic a = #C1}) → dynamic
+    return true;
+  operator <=({dynamic a = #C1}) → dynamic
+    return true;
+  operator >=({dynamic a = #C1}) → dynamic
+    return true;
+  operator -({dynamic a = #C1}) → dynamic
+    return true;
+  operator +({dynamic a = #C1}) → dynamic
+    return true;
+  operator /({dynamic a = #C1}) → dynamic
+    return true;
+  operator ~/({dynamic a = #C1}) → dynamic
+    return true;
+  operator *({dynamic a = #C1}) → dynamic
+    return true;
+  operator %({dynamic a = #C1}) → dynamic
+    return true;
+  operator |({dynamic a = #C1}) → dynamic
+    return true;
+  operator ^({dynamic a = #C1}) → dynamic
+    return true;
+  operator &({dynamic a = #C1}) → dynamic
+    return true;
+  operator <<({dynamic a = #C1}) → dynamic
+    return true;
+  operator >>({dynamic a = #C1}) → dynamic
+    return true;
+  operator []=({dynamic a = #C1, dynamic b = #C1}) → void
+    return true;
+  operator []({dynamic a = #C1}) → dynamic
+    return true;
+  operator ~({dynamic a = #C1}) → dynamic
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Operators5 extends core::Object {
+  synthetic constructor •() → self::Operators5*
+    : super core::Object::•()
+    ;
+  operator ==(dynamic a, [dynamic b = #C1]) → core::bool*
+    return true;
+  operator <(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator >(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator <=(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator >=(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator -(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator +(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator /(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator ~/(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator *(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator %(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator |(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator ^(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator &(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator <<(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator >>(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator []=(dynamic a, dynamic b, [dynamic c = #C1]) → void
+    return true;
+  operator [](dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  operator ~(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Operators6 extends core::Object {
+  synthetic constructor •() → self::Operators6*
+    : super core::Object::•()
+    ;
+  operator ==(dynamic a, {dynamic b = #C1}) → core::bool*
+    return true;
+  operator <(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator >(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator <=(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator >=(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator -(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator +(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator /(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator ~/(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator *(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator %(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator |(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator ^(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator &(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator <<(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator >>(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator []=(dynamic a, dynamic b, {dynamic c = #C1}) → void
+    return true;
+  operator [](dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  operator ~(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Operators7 extends core::Object {
+  synthetic constructor •() → self::Operators7*
+    : super core::Object::•()
+    ;
+  operator ==<T extends core::Object* = dynamic>(invalid-type a) → invalid-type
+    return true;
+  operator ><T extends core::Object* = dynamic>(dynamic a) → dynamic
+    return true;
+  operator <=<T extends core::Object* = dynamic>(dynamic a) → dynamic
+    return true;
+  operator >=<T extends core::Object* = dynamic>(dynamic a) → dynamic
+    return true;
+  operator unary-<T extends core::Object* = dynamic>() → dynamic
+    return true;
+  operator -<T extends core::Object* = dynamic>(dynamic a) → dynamic
+    return true;
+  operator +<T extends core::Object* = dynamic>(dynamic a) → dynamic
+    return true;
+  operator /<T extends core::Object* = dynamic>(dynamic a) → dynamic
+    return true;
+  operator ~/<T extends core::Object* = dynamic>(dynamic a) → dynamic
+    return true;
+  operator *<T extends core::Object* = dynamic>(dynamic a) → dynamic
+    return true;
+  operator %<T extends core::Object* = dynamic>(dynamic a) → dynamic
+    return true;
+  operator |<T extends core::Object* = dynamic>(dynamic a) → dynamic
+    return true;
+  operator ^<T extends core::Object* = dynamic>(dynamic a) → dynamic
+    return true;
+  operator &<T extends core::Object* = dynamic>(dynamic a) → dynamic
+    return true;
+  operator <<<T extends core::Object* = dynamic>(dynamic a) → dynamic
+    return true;
+  operator >><T extends core::Object* = dynamic>(dynamic a) → dynamic
+    return true;
+  operator []=<T extends core::Object* = dynamic>(dynamic a, dynamic b) → void
+    return true;
+  operator []<T extends core::Object* = dynamic>(dynamic a) → dynamic
+    return true;
+  operator ~<T extends core::Object* = dynamic>() → dynamic
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/invalid_operator.dart.weak.outline.expect b/pkg/front_end/testcases/general/invalid_operator.dart.weak.outline.expect
index c1ee228..c9f7e40 100644
--- a/pkg/front_end/testcases/general/invalid_operator.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/general/invalid_operator.dart.weak.outline.expect
@@ -564,35 +564,35 @@
 // Try adding explicit types.
 //   operator ==<T>(a) => true;
 //            ^^
-// sdk/lib/_internal/vm/lib/object_patch.dart:29:26: Context: This is one of the overridden members.
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is one of the overridden members.
 //   external bool operator ==(Object other);
 //                          ^^
 //
 // pkg/front_end/testcases/general/invalid_operator.dart:6:12: Error: The method 'Operators1.==' has fewer positional arguments than those of overridden method 'Object.=='.
 //   operator ==() => true;
 //            ^
-// sdk/lib/_internal/vm/lib/object_patch.dart:29:26: Context: This is the overridden method ('==').
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
 //   external bool operator ==(Object other);
 //                          ^
 //
 // pkg/front_end/testcases/general/invalid_operator.dart:27:12: Error: The method 'Operators2.==' has more required arguments than those of overridden method 'Object.=='.
 //   operator ==(a, b) => true;
 //            ^
-// sdk/lib/_internal/vm/lib/object_patch.dart:29:26: Context: This is the overridden method ('==').
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
 //   external bool operator ==(Object other);
 //                          ^
 //
 // pkg/front_end/testcases/general/invalid_operator.dart:71:12: Error: The method 'Operators4.==' has fewer positional arguments than those of overridden method 'Object.=='.
 //   operator ==({a}) => true;
 //            ^
-// sdk/lib/_internal/vm/lib/object_patch.dart:29:26: Context: This is the overridden method ('==').
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
 //   external bool operator ==(Object other);
 //                          ^
 //
 // pkg/front_end/testcases/general/invalid_operator.dart:137:12: Error: Declared type variables of 'Operators7.==' doesn't match those on overridden method 'Object.=='.
 //   operator ==<T>(a) => true;
 //            ^
-// sdk/lib/_internal/vm/lib/object_patch.dart:29:26: Context: This is the overridden method ('==').
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
 //   external bool operator ==(Object other);
 //                          ^
 //
diff --git a/pkg/front_end/testcases/general/invalid_operator2.dart.weak.modular.expect b/pkg/front_end/testcases/general/invalid_operator2.dart.weak.modular.expect
new file mode 100644
index 0000000..7ad624a
--- /dev/null
+++ b/pkg/front_end/testcases/general/invalid_operator2.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/invalid_operator2.dart:6:12: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   operator <<T>(a) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator2.dart:6:14: Error: Expected '{' before this.
+//   operator <<T>(a) => true;
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator2.dart:6:12: Error: Operator '<<' should have exactly one parameter.
+//   operator <<T>(a) => true;
+//            ^^
+//
+// pkg/front_end/testcases/general/invalid_operator2.dart:6:15: Error: Operator declarations must be preceded by the keyword 'operator'.
+// Try adding the keyword 'operator'.
+//   operator <<T>(a) => true;
+//               ^
+//
+// pkg/front_end/testcases/general/invalid_operator2.dart:6:14: Error: Type 'T' not found.
+//   operator <<T>(a) => true;
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Operators7 extends core::Object {
+  synthetic constructor •() → self::Operators7*
+    : super core::Object::•()
+    ;
+  operator <<() → dynamic {}
+  operator >(dynamic a) → invalid-type
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/invalid_operator_override.dart.weak.modular.expect b/pkg/front_end/testcases/general/invalid_operator_override.dart.weak.modular.expect
new file mode 100644
index 0000000..aad884f
--- /dev/null
+++ b/pkg/front_end/testcases/general/invalid_operator_override.dart.weak.modular.expect
@@ -0,0 +1,120 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/invalid_operator_override.dart:13:18: Error: The parameter 'b' of the method 'B.+' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'A.+'.
+//  - 'B' is from 'pkg/front_end/testcases/general/invalid_operator_override.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/invalid_operator_override.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   A operator +(B b) => b;
+//                  ^
+// pkg/front_end/testcases/general/invalid_operator_override.dart:6:14: Context: This is the overridden method ('+').
+//   A operator +(A a) => a;
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator_override.dart:14:14: Error: The return type of the method 'B.unary-' is 'A', which does not match the return type, 'B', of the overridden method, 'A.unary-'.
+//  - 'A' is from 'pkg/front_end/testcases/general/invalid_operator_override.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/general/invalid_operator_override.dart'.
+// Change to a subtype of 'B'.
+//   A operator -() => this;
+//              ^
+// pkg/front_end/testcases/general/invalid_operator_override.dart:7:14: Context: This is the overridden method ('unary-').
+//   B operator -() => new B();
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator_override.dart:15:19: Error: The parameter 'b' of the method 'B.[]' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'A.[]'.
+//  - 'B' is from 'pkg/front_end/testcases/general/invalid_operator_override.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/invalid_operator_override.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   B operator [](B b) => b;
+//                   ^
+// pkg/front_end/testcases/general/invalid_operator_override.dart:8:14: Context: This is the overridden method ('[]').
+//   B operator [](A a) => new B();
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator_override.dart:16:23: Error: The parameter 'b' of the method 'B.[]=' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'A.[]='.
+//  - 'B' is from 'pkg/front_end/testcases/general/invalid_operator_override.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/invalid_operator_override.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   void operator []=(B b, A a) {}
+//                       ^
+// pkg/front_end/testcases/general/invalid_operator_override.dart:9:17: Context: This is the overridden method ('[]=').
+//   void operator []=(A a1, A a2) {}
+//                 ^
+//
+// pkg/front_end/testcases/general/invalid_operator_override.dart:20:14: Error: The return type of the method 'C.[]' is 'A', which does not match the return type, 'B', of the overridden method, 'A.[]'.
+//  - 'A' is from 'pkg/front_end/testcases/general/invalid_operator_override.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/general/invalid_operator_override.dart'.
+// Change to a subtype of 'B'.
+//   A operator [](B b) => b;
+//              ^
+// pkg/front_end/testcases/general/invalid_operator_override.dart:8:14: Context: This is the overridden method ('[]').
+//   B operator [](A a) => new B();
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator_override.dart:20:19: Error: The parameter 'b' of the method 'C.[]' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'A.[]'.
+//  - 'B' is from 'pkg/front_end/testcases/general/invalid_operator_override.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/invalid_operator_override.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   A operator [](B b) => b;
+//                   ^
+// pkg/front_end/testcases/general/invalid_operator_override.dart:8:14: Context: This is the overridden method ('[]').
+//   B operator [](A a) => new B();
+//              ^
+//
+// pkg/front_end/testcases/general/invalid_operator_override.dart:21:28: Error: The parameter 'b' of the method 'C.[]=' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'A.[]='.
+//  - 'B' is from 'pkg/front_end/testcases/general/invalid_operator_override.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/invalid_operator_override.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   void operator []=(A a, B b) {}
+//                            ^
+// pkg/front_end/testcases/general/invalid_operator_override.dart:9:17: Context: This is the overridden method ('[]=').
+//   void operator []=(A a1, A a2) {}
+//                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator +(self::A* a) → self::A*
+    return a;
+  operator unary-() → self::B*
+    return new self::B::•();
+  operator [](self::A* a) → self::B*
+    return new self::B::•();
+  operator []=(self::A* a1, self::A* a2) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::B* b) → self::A*
+    return b;
+  operator unary-() → self::A*
+    return this;
+  operator [](self::B* b) → self::B*
+    return b;
+  operator []=(self::B* b, self::A* a) → void {}
+}
+class C extends self::A {
+  synthetic constructor •() → self::C*
+    : super self::A::•()
+    ;
+  operator [](self::B* b) → self::A*
+    return b;
+  operator []=(self::A* a, self::B* b) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/invalid_setter_return_type.dart.weak.modular.expect b/pkg/front_end/testcases/general/invalid_setter_return_type.dart.weak.modular.expect
new file mode 100644
index 0000000..096efed
--- /dev/null
+++ b/pkg/front_end/testcases/general/invalid_setter_return_type.dart.weak.modular.expect
@@ -0,0 +1,110 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/invalid_setter_return_type.dart:5:1: Error: The return type of the setter must be 'void' or absent.
+// Try removing the return type, or define a method rather than a setter.
+// int set setter1(_) {} // error
+// ^
+//
+// pkg/front_end/testcases/general/invalid_setter_return_type.dart:6:1: Error: The return type of the setter must be 'void' or absent.
+// Try removing the return type, or define a method rather than a setter.
+// dynamic set setter2(_) {} // error
+// ^
+//
+// pkg/front_end/testcases/general/invalid_setter_return_type.dart:11:3: Error: The return type of the setter must be 'void' or absent.
+// Try removing the return type, or define a method rather than a setter.
+//   int set setter1(_) {} // error
+//   ^
+//
+// pkg/front_end/testcases/general/invalid_setter_return_type.dart:12:3: Error: The return type of the operator []= must be 'void'.
+// Try changing the return type to 'void'.
+//   int operator []=(a, b) {} // error
+//   ^
+//
+// pkg/front_end/testcases/general/invalid_setter_return_type.dart:16:3: Error: The return type of the setter must be 'void' or absent.
+// Try removing the return type, or define a method rather than a setter.
+//   dynamic set setter2(_) {} // error
+//   ^
+//
+// pkg/front_end/testcases/general/invalid_setter_return_type.dart:17:3: Error: The return type of the operator []= must be 'void'.
+// Try changing the return type to 'void'.
+//   dynamic operator []=(a, b) {} // error
+//   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1*
+    : super core::Object::•()
+    ;
+  set setter1(dynamic _) → void {}
+  operator []=(dynamic a, dynamic b) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2*
+    : super core::Object::•()
+    ;
+  set setter2(dynamic _) → void {}
+  operator []=(dynamic a, dynamic b) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class3 extends core::Object {
+  synthetic constructor •() → self::Class3*
+    : super core::Object::•()
+    ;
+  set setter3(dynamic _) → void {}
+  operator []=(dynamic a, dynamic b) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class4 extends core::Object {
+  synthetic constructor •() → self::Class4*
+    : super core::Object::•()
+    ;
+  set setter4(dynamic _) → void {}
+  operator []=(dynamic a, dynamic b) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static set setter1(dynamic _) → void {}
+static set setter2(dynamic _) → void {}
+static set setter3(dynamic _) → void {}
+static set setter4(dynamic _) → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/invalid_super_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/general/invalid_super_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..09921df
--- /dev/null
+++ b/pkg/front_end/testcases/general/invalid_super_initializer.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/invalid_super_initializer.dart:8:8: Error: Can't use 'super' as an expression.
+// To delegate a constructor to a super constructor, put the super call as an initializer.
+//   B(): super()?.foo() {}
+//        ^
+//
+// pkg/front_end/testcases/general/invalid_super_initializer.dart:8:8: Error: Expected an initializer.
+//   B(): super()?.foo() {}
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class B extends self::A {
+  constructor •() → self::B
+    : final dynamic #t1 = let final invalid-type #t2 = invalid-expression "pkg/front_end/testcases/general/invalid_super_initializer.dart:8:8: Error: Can't use 'super' as an expression.
+To delegate a constructor to a super constructor, put the super call as an initializer.
+  B(): super()?.foo() {}
+       ^" in #t2 == null ?{dynamic} null : #t2{dynamic}.foo() {}
+}
+static method bad() → dynamic {
+  new self::B::•();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/invalid_type.dart.weak.modular.expect b/pkg/front_end/testcases/general/invalid_type.dart.weak.modular.expect
new file mode 100644
index 0000000..5bf84b6
--- /dev/null
+++ b/pkg/front_end/testcases/general/invalid_type.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/invalid_type.dart:7:5: Error: Expected identifier, but got 'this'.
+//     this.bar();
+//     ^^^^
+//
+// pkg/front_end/testcases/general/invalid_type.dart:12:12: Error: 'Missing' isn't a type.
+//   (null as Missing).bar();
+//            ^^^^^^^
+//
+// pkg/front_end/testcases/general/invalid_type.dart:13:8: Error: The method 'bar' isn't defined for the class 'Null'.
+// Try correcting the name to the name of an existing method, or defining a method named 'bar'.
+//   null.bar();
+//        ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  static method foo() → dynamic {
+    invalid-expression "pkg/front_end/testcases/general/invalid_type.dart:7:5: Error: Expected identifier, but got 'this'.
+    this.bar();
+    ^^^^"{dynamic}.bar();
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  (null as invalid-type){dynamic}.bar();
+  invalid-expression "pkg/front_end/testcases/general/invalid_type.dart:13:8: Error: The method 'bar' isn't defined for the class 'Null'.
+Try correcting the name to the name of an existing method, or defining a method named 'bar'.
+  null.bar();
+       ^^^" in null{<unresolved>}.bar();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/invocations.dart.weak.modular.expect b/pkg/front_end/testcases/general/invocations.dart.weak.modular.expect
new file mode 100644
index 0000000..64be843
--- /dev/null
+++ b/pkg/front_end/testcases/general/invocations.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/invocations.dart:7:3: Error: Method not found: 'z'.
+//   z("Hello, World!");
+//   ^
+//
+// pkg/front_end/testcases/general/invocations.dart:8:3: Error: Undefined name 'z'.
+//   z.print("Hello, World!");
+//   ^
+//
+// pkg/front_end/testcases/general/invocations.dart:9:3: Error: Undefined name 'y'.
+//   y.z.print("Hello, World!");
+//   ^
+//
+// pkg/front_end/testcases/general/invocations.dart:10:3: Error: Undefined name 'x'.
+//   x.y.z.print("Hello, World!");
+//   ^
+//
+// pkg/front_end/testcases/general/invocations.dart:14:7: Error: Method not found: 'z'.
+//       z("Hello, World!") +
+//       ^
+//
+// pkg/front_end/testcases/general/invocations.dart:15:7: Error: Undefined name 'z'.
+//       z.print("Hello, World!") +
+//       ^
+//
+// pkg/front_end/testcases/general/invocations.dart:16:7: Error: Undefined name 'y'.
+//       y.z.print("Hello, World!") +
+//       ^
+//
+// pkg/front_end/testcases/general/invocations.dart:17:7: Error: Undefined name 'x'.
+//       x.y.z.print("Hello, World!");
+//       ^
+//
+// pkg/front_end/testcases/general/invocations.dart:13:7: Error: This expression has type 'void' and can't be used.
+//       print("Hello, World!") +
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::print("Hello, World!");
+  invalid-expression "pkg/front_end/testcases/general/invocations.dart:7:3: Error: Method not found: 'z'.
+  z(\"Hello, World!\");
+  ^";
+  invalid-expression "pkg/front_end/testcases/general/invocations.dart:8:3: Error: Undefined name 'z'.
+  z.print(\"Hello, World!\");
+  ^"{dynamic}.print("Hello, World!");
+  invalid-expression "pkg/front_end/testcases/general/invocations.dart:9:3: Error: Undefined name 'y'.
+  y.z.print(\"Hello, World!\");
+  ^"{<invalid>}.z{dynamic}.print("Hello, World!");
+  invalid-expression "pkg/front_end/testcases/general/invocations.dart:10:3: Error: Undefined name 'x'.
+  x.y.z.print(\"Hello, World!\");
+  ^"{<invalid>}.y{<invalid>}.z{dynamic}.print("Hello, World!");
+  1.{core::num::+}(invalid-expression "pkg/front_end/testcases/general/invocations.dart:13:7: Error: This expression has type 'void' and can't be used.
+      print(\"Hello, World!\") +
+      ^" in core::print("Hello, World!")){(core::num*) →* core::num*}.{core::num::+}(invalid-expression "pkg/front_end/testcases/general/invocations.dart:14:7: Error: Method not found: 'z'.
+      z(\"Hello, World!\") +
+      ^"){(core::num*) →* core::num*}.{core::num::+}(invalid-expression "pkg/front_end/testcases/general/invocations.dart:15:7: Error: Undefined name 'z'.
+      z.print(\"Hello, World!\") +
+      ^"{dynamic}.print("Hello, World!") as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*}.{core::num::+}(invalid-expression "pkg/front_end/testcases/general/invocations.dart:16:7: Error: Undefined name 'y'.
+      y.z.print(\"Hello, World!\") +
+      ^"{<invalid>}.z{dynamic}.print("Hello, World!") as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*}.{core::num::+}(invalid-expression "pkg/front_end/testcases/general/invocations.dart:17:7: Error: Undefined name 'x'.
+      x.y.z.print(\"Hello, World!\");
+      ^"{<invalid>}.y{<invalid>}.z{dynamic}.print("Hello, World!") as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+}
diff --git a/pkg/front_end/testcases/general/issue129167943.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue129167943.dart.weak.modular.expect
new file mode 100644
index 0000000..dbcaed7
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue129167943.dart.weak.modular.expect
@@ -0,0 +1,244 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract method foo(core::num* x) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object implements self::B {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract method foo(covariant-by-declaration core::int* x) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D1 extends core::Object implements self::A, self::C, self::B {
+  synthetic constructor •() → self::D1*
+    : super core::Object::•()
+    ;
+  abstract method foo(covariant-by-declaration core::int* x) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D2 extends core::Object implements self::A, self::C, self::B {
+  synthetic constructor •() → self::D2*
+    : super core::Object::•()
+    ;
+  method foo(covariant-by-declaration core::int* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D3 extends core::Object implements self::A, self::C, self::B {
+  synthetic constructor •() → self::D3*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract forwarding-stub method foo(covariant-by-declaration core::num* x) → void;
+}
+abstract class D4 extends core::Object implements self::A, self::C, self::B {
+  synthetic constructor •() → self::D4*
+    : super core::Object::•()
+    ;
+  abstract method foo(covariant-by-declaration core::int* x) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D5 extends core::Object implements self::A, self::C, self::B {
+  synthetic constructor •() → self::D5*
+    : super core::Object::•()
+    ;
+  abstract method foo(covariant-by-declaration core::num* x) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class E extends core::Object {
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  abstract set foo(core::num* x) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class G extends core::Object implements self::E {
+  synthetic constructor •() → self::G*
+    : super core::Object::•()
+    ;
+  abstract set foo(covariant-by-declaration core::int* x) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class H1 extends core::Object implements self::A, self::E, self::G {
+  synthetic constructor •() → self::H1*
+    : super core::Object::•()
+    ;
+  abstract set foo(covariant-by-declaration core::int* x) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class H2 extends core::Object implements self::A, self::E, self::G {
+  synthetic constructor •() → self::H2*
+    : super core::Object::•()
+    ;
+  set foo(covariant-by-declaration core::int* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class H3 extends core::Object implements self::A, self::E, self::G {
+  synthetic constructor •() → self::H3*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract forwarding-stub set foo(covariant-by-declaration core::num* x) → void;
+}
+abstract class H4 extends core::Object implements self::A, self::E, self::G {
+  synthetic constructor •() → self::H4*
+    : super core::Object::•()
+    ;
+  abstract set foo(covariant-by-declaration core::int* x) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class H5 extends core::Object implements self::A, self::E, self::G {
+  synthetic constructor •() → self::H5*
+    : super core::Object::•()
+    ;
+  abstract set foo(covariant-by-declaration core::num* x) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue31767.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue31767.dart.weak.modular.expect
new file mode 100644
index 0000000..af92d7d
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue31767.dart.weak.modular.expect
@@ -0,0 +1,135 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "issue31767_lib.dart" as iss;
+
+import "org-dartlang-testcase:///issue31767_lib.dart";
+
+class C extends core::Object {
+  final field core::int* w;
+  constructor foo(core::int* x, [core::int* y = #C1, core::int* z = #C1]) → self::C*
+    : self::C::w = self::p("x", x).{core::num::+}(self::p("y", y)){(core::num*) →* core::int*}.{core::num::+}(self::p("z", z)){(core::num*) →* core::int*}, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M extends self::C /*isMixinDeclaration*/  {
+  get w2() → core::int*
+    return this.{self::C::w}{core::int*}.{core::num::*}(this.{self::C::w}{core::int*}){(core::num*) →* core::int*};
+}
+class D = self::C with self::M {
+  synthetic constructor foo(core::int* x, [core::int* y = #C1, core::int* z = #C1]) → self::D*
+    : super self::C::foo(x, y, z)
+    ;
+  mixin-super-stub get w2() → core::int*
+    return super.{self::M::w2};
+}
+abstract class N extends iss::A /*isMixinDeclaration*/  {
+  get w2() → core::int*
+    return this.{iss::A::w}{core::int*}.{core::num::*}(this.{iss::A::w}{core::int*}){(core::num*) →* core::int*};
+}
+class E = iss::A with self::N {
+  synthetic constructor foo(core::int* x, [core::int* y = #C2, core::int* z = #C2, iss::_A* a = #C4]) → self::E*
+    : super iss::A::foo(x, y, z, a)
+    ;
+  mixin-super-stub get w2() → core::int*
+    return super.{self::N::w2};
+}
+static field core::StringBuffer* sb;
+static method p(core::String* name, core::int* value) → core::int* {
+  self::sb.{core::StringBuffer::write}("${name} = ${value}, "){(core::Object*) →* void};
+  return value;
+}
+static method main() → dynamic {
+  self::sb = new core::StringBuffer::•();
+  iss::A* a = new iss::A::foo(1, 2);
+  self::expect("x = 1, y = 2, z = 3, ", self::sb.{core::StringBuffer::toString}(){() →* core::String*});
+  self::expect(6, a.{iss::A::w}{core::int*});
+  self::expect(5, a.{iss::A::a}{iss::_A*}.{iss::_A::field}{core::int*});
+  self::sb = new core::StringBuffer::•();
+  self::C* c = new self::C::foo(1, 2);
+  self::expect("x = 1, y = 2, z = 0, ", self::sb.{core::StringBuffer::toString}(){() →* core::String*});
+  self::expect(3, c.{self::C::w}{core::int*});
+  self::sb = new core::StringBuffer::•();
+  self::D* d = new self::D::foo(1, 2);
+  self::expect("x = 1, y = 2, z = 0, ", self::sb.{core::StringBuffer::toString}(){() →* core::String*});
+  self::expect(3, d.{self::C::w}{core::int*});
+  self::expect(9, d.{self::D::w2}{core::int*});
+  self::sb = new core::StringBuffer::•();
+  self::E* e = new self::E::foo(1, 2);
+  self::expect("x = 1, y = 2, z = 3, ", self::sb.{core::StringBuffer::toString}(){() →* core::String*});
+  self::expect(6, e.{iss::A::w}{core::int*});
+  self::expect(36, e.{self::E::w2}{core::int*});
+  self::expect(5, e.{iss::A::a}{iss::_A*}.{iss::_A::field}{core::int*});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+library;
+import self as iss;
+import "dart:core" as core;
+import "issue31767.dart" as self;
+
+import "org-dartlang-testcase:///issue31767.dart";
+
+class A extends core::Object {
+  final field core::int* w;
+  final field iss::_A* a;
+  constructor foo(core::int* x, [core::int* y = #C2, core::int* z = #C2, iss::_A* a = #C4]) → iss::A*
+    : iss::A::a = a, iss::A::w = self::p("x", x).{core::num::+}(self::p("y", y)){(core::num*) →* core::int*}.{core::num::+}(self::p("z", z)){(core::num*) →* core::int*}, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class _A extends core::Object /*hasConstConstructor*/  {
+  final field core::int* field;
+  const constructor •(core::int* field) → iss::_A*
+    : iss::_A::field = field, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field core::int* _private = #C2;
+
+constants  {
+  #C1 = 0
+  #C2 = 3
+  #C3 = 5
+  #C4 = iss::_A {field:#C3}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue31767.dart:
+- _A. (from org-dartlang-testcase:///issue31767_lib.dart:20:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+
+org-dartlang-testcase:///issue31767_lib.dart:
+- _A. (from org-dartlang-testcase:///issue31767_lib.dart:20:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/issue31767.dart.weak.outline.expect b/pkg/front_end/testcases/general/issue31767.dart.weak.outline.expect
index 43bfbd8..d4d8c65 100644
--- a/pkg/front_end/testcases/general/issue31767.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/general/issue31767.dart.weak.outline.expect
@@ -7,7 +7,7 @@
 
 class C extends core::Object {
   final field core::int* w;
-  constructor foo(core::int* x, [core::int* y, core::int* z]) → self::C*
+  constructor foo(core::int* x, [core::int* y = 0, core::int* z = 0]) → self::C*
     ;
   abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
   abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
@@ -59,7 +59,7 @@
 class A extends core::Object {
   final field core::int* w;
   final field iss::_A* a;
-  constructor foo(core::int* x, [core::int* y, core::int* z, iss::_A* a]) → iss::A*
+  constructor foo(core::int* x, [core::int* y = iss::_private, core::int* z = iss::_private, iss::_A* a = const iss::_A::•(5)]) → iss::A*
     ;
   abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
   abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
@@ -89,3 +89,10 @@
   abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
 }
 static const field core::int* _private = 3;
+
+
+Extra constant evaluation status:
+Evaluated: StaticGet @ org-dartlang-testcase:///issue31767_lib.dart:14:25 -> IntConstant(3)
+Evaluated: StaticGet @ org-dartlang-testcase:///issue31767_lib.dart:14:43 -> IntConstant(3)
+Evaluated: ConstructorInvocation @ org-dartlang-testcase:///issue31767_lib.dart:14:68 -> InstanceConstant(const _A{_A.field: 5})
+Extra constant evaluation: evaluated: 13, effectively constant: 3
diff --git a/pkg/front_end/testcases/general/issue34515.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue34515.dart.weak.modular.expect
new file mode 100644
index 0000000..6ca6a9d
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue34515.dart.weak.modular.expect
@@ -0,0 +1,67 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue34515.dart:9:3: Error: 'ImportedClass' is imported from both 'pkg/front_end/testcases/general/issue34515_lib1.dart' and 'pkg/front_end/testcases/general/issue34515_lib2.dart'.
+//   ImportedClass(1);
+//   ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/issue34515.dart:10:3: Error: 'ImportedClass' is imported from both 'pkg/front_end/testcases/general/issue34515_lib1.dart' and 'pkg/front_end/testcases/general/issue34515_lib2.dart'.
+//   ImportedClass("a");
+//   ^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue34515_lib1.dart";
+import "org-dartlang-testcase:///issue34515_lib2.dart";
+
+static method test() → void {
+  let final core::Object* #t1 = 1 in invalid-expression "pkg/front_end/testcases/general/issue34515.dart:9:3: Error: 'ImportedClass' is imported from both 'pkg/front_end/testcases/general/issue34515_lib1.dart' and 'pkg/front_end/testcases/general/issue34515_lib2.dart'.
+  ImportedClass(1);
+  ^^^^^^^^^^^^^";
+  let final core::Object* #t2 = "a" in invalid-expression "pkg/front_end/testcases/general/issue34515.dart:10:3: Error: 'ImportedClass' is imported from both 'pkg/front_end/testcases/general/issue34515_lib1.dart' and 'pkg/front_end/testcases/general/issue34515_lib2.dart'.
+  ImportedClass(\"a\");
+  ^^^^^^^^^^^^^";
+}
+static method main() → dynamic {}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+class ImportedClass extends core::Object {
+  constructor •(core::int* a) → self2::ImportedClass*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+library;
+import self as self3;
+import "dart:core" as core;
+
+class ImportedClass extends core::Object {
+  constructor •(core::String* a) → self3::ImportedClass*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/general/issue34714.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue34714.dart.weak.modular.expect
new file mode 100644
index 0000000..c0cc024
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue34714.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  static factory •<T extends core::Object* = dynamic>() → self::A<self::A::•::T*>*
+    return new self::B::•<self::A::•::T*>();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::Object* = dynamic> extends core::Object implements self::A<self::B::T*> {
+  constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::A::•
+}
diff --git a/pkg/front_end/testcases/general/issue34899.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue34899.dart.weak.modular.expect
new file mode 100644
index 0000000..c1735e3
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue34899.dart.weak.modular.expect
@@ -0,0 +1,76 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+class Foo<T extends core::Object* = dynamic> extends core::Object {
+  final field () →* asy::Future<dynamic>* quux;
+  covariant-by-class field self::Foo::T* t;
+  constructor •(() →* asy::Future<dynamic>* quux, self::Foo::T* t) → self::Foo<self::Foo::T*>*
+    : self::Foo::quux = quux, self::Foo::t = t, super core::Object::•()
+    ;
+  method call() → asy::Future<self::Foo::T*>*
+    return this.{self::Foo::quux}{() →* asy::Future<dynamic>*}(){() →* asy::Future<dynamic>*}.{asy::Future::then}<self::Foo::T*>((dynamic _) → self::Foo::T* => this.{self::Foo::t}{self::Foo::T*}){((dynamic) →* FutureOr<self::Foo::T*>*, {onError: core::Function*}) →* asy::Future<self::Foo::T*>*};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar extends core::Object {
+  field self::Foo<self::Baz*>* qux = null;
+  synthetic constructor •() → self::Bar*
+    : super core::Object::•()
+    ;
+  method quuz() → asy::Future<void>*
+    return this.{self::Bar::qux}{self::Foo<self::Baz*>*}.{self::Foo::call}(){() →* asy::Future<self::Baz*>*}.{asy::Future::then}<self::Grault*>((self::Baz* baz) → self::Grault* => this.{self::Bar::corge}(baz){(self::Baz*) →* self::Grault*}){((self::Baz*) →* FutureOr<self::Grault*>*, {onError: core::Function*}) →* asy::Future<self::Grault*>*}.{asy::Future::then}<void>((self::Grault* grault) → void => this.{self::Bar::garply}(grault){(self::Grault*) →* void}){((self::Grault*) →* FutureOr<void>*, {onError: core::Function*}) →* asy::Future<void>*};
+  method corge(self::Baz* baz) → self::Grault*
+    return null;
+  method garply(self::Grault* grault) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Baz extends core::Object {
+  synthetic constructor •() → self::Baz*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Grault extends core::Object {
+  synthetic constructor •() → self::Grault*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue35875.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue35875.dart.weak.modular.expect
new file mode 100644
index 0000000..fe26450
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue35875.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* a = null;
+  constructor •(core::int* a) → self::A*
+    : super core::Object::•() {
+    this.{self::A::a} = a;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue37027.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue37027.dart.weak.modular.expect
new file mode 100644
index 0000000..eeb421b
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue37027.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+class C extends core::Object {
+  final field core::Set<core::int> s;
+  constructor •(core::List<core::int> ell) → self::C
+    : self::C::s = block {
+      final core::Set<core::int> #t1 = col::LinkedHashSet::•<core::int>();
+      for (core::int e in ell)
+        if(e.{core::int::isOdd}{core::bool})
+          #t1.{core::Set::add}{Invariant}(2.{core::num::*}(e){(core::num) → core::int}){(core::int) → core::bool};
+    } =>#t1, super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue37381.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue37381.dart.weak.modular.expect
new file mode 100644
index 0000000..8ec0e22
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue37381.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  method f<R extends core::Object* = dynamic>(<X extends core::Object* = dynamic>(self::A<X*>*) →* self::A::f::R* f) → self::A::f::R*
+    return f<self::A::X*>(this){(self::A<self::A::X*>*) →* self::A::f::R*};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::A<core::num*>* a = new self::A::•<core::int*>();
+  a.{self::A::f}<core::int*>(<X extends core::Object* = dynamic>(self::A<X*>* _) → core::int* => 42){(<X extends core::Object* = dynamic>(self::A<X*>*) →* core::int*) →* core::int*};
+}
diff --git a/pkg/front_end/testcases/general/issue37753.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue37753.dart.weak.modular.expect
new file mode 100644
index 0000000..8ce1e9b
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue37753.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method getElements() → core::Iterable<core::int*>* sync* {
+  core::Iterable<core::int*>* elements;
+  elements = (() → core::Iterable<core::int*>* sync* {
+    yield 7;
+  })(){() →* core::Iterable<core::int*>*};
+  yield* elements;
+}
+static method main() → dynamic
+  return core::print(self::getElements());
diff --git a/pkg/front_end/testcases/general/issue37776.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue37776.dart.weak.modular.expect
new file mode 100644
index 0000000..7840a4b
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue37776.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue37776.dart:11:7: Error: 'X' is already declared in this scope.
+// class X {
+//       ^
+// pkg/front_end/testcases/general/issue37776.dart:7:7: Context: Previous declaration of 'X'.
+// class X {
+//       ^
+//
+// pkg/front_end/testcases/general/issue37776.dart:16:9: Error: Couldn't find constructor 'X.foo'.
+//   const X.foo();
+//         ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class X#1 extends core::Object /*hasConstConstructor*/  {
+  const constructor foo() → self::X#1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class X extends core::Object /*hasConstConstructor*/  {
+  const constructor foo() → self::X*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {
+  invalid-expression "pkg/front_end/testcases/general/issue37776.dart:16:9: Error: Couldn't find constructor 'X.foo'.
+  const X.foo();
+        ^^^";
+}
diff --git a/pkg/front_end/testcases/general/issue38253.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue38253.dart.weak.modular.expect
new file mode 100644
index 0000000..293f3f6
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue38253.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue38253.dart:9:1: Error: Expected ';' after this.
+// }
+// ^
+//
+// pkg/front_end/testcases/general/issue38253.dart:6:3: Error: 'g' isn't a type.
+//   g f(){
+//   ^
+//
+// pkg/front_end/testcases/general/issue38253.dart:7:5: Error: A value must be explicitly returned from a non-void function.
+//     return;
+//     ^
+//
+import self as self;
+
+static field () → Null a = () → Null {
+  function f() → invalid-type {
+    return invalid-expression "pkg/front_end/testcases/general/issue38253.dart:7:5: Error: A value must be explicitly returned from a non-void function.
+    return;
+    ^" in null;
+  }
+};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue38253b.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue38253b.dart.weak.modular.expect
new file mode 100644
index 0000000..3d3ebd1
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue38253b.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue38253b.dart:6:3: Error: 'g' isn't a type.
+//   g f1() {
+//   ^
+//
+// pkg/front_end/testcases/general/issue38253b.dart:10:3: Error: 'g' isn't a type.
+//   g f2() async {
+//   ^
+//
+// pkg/front_end/testcases/general/issue38253b.dart:7:5: Error: A value must be explicitly returned from a non-void function.
+//     return;
+//     ^
+//
+// pkg/front_end/testcases/general/issue38253b.dart:11:5: Error: A value must be explicitly returned from a non-void async function.
+//     return;
+//     ^
+//
+import self as self;
+
+static field () → Null a = () → Null {
+  function f1() → invalid-type {
+    return invalid-expression "pkg/front_end/testcases/general/issue38253b.dart:7:5: Error: A value must be explicitly returned from a non-void function.
+    return;
+    ^" in null;
+  }
+  function f2() → invalid-type async {
+    return invalid-expression "pkg/front_end/testcases/general/issue38253b.dart:11:5: Error: A value must be explicitly returned from a non-void async function.
+    return;
+    ^" in null;
+  }
+};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue38253c.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue38253c.dart.weak.modular.expect
new file mode 100644
index 0000000..2de98d4
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue38253c.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue38253c.dart:6:3: Error: 'g' isn't a type.
+//   g f1() {}
+//   ^
+//
+// pkg/front_end/testcases/general/issue38253c.dart:7:3: Error: 'g' isn't a type.
+//   g f2() async {}
+//   ^
+//
+// pkg/front_end/testcases/general/issue38253c.dart:8:3: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+//   int f3() {}
+//   ^
+//
+// pkg/front_end/testcases/general/issue38253c.dart:9:3: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+//   Future<int> f4() async {}
+//   ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+static field () → Null a = () → Null {
+  function f1() → invalid-type {}
+  function f2() → invalid-type async {}
+  function f3() → core::int {
+    return invalid-expression "pkg/front_end/testcases/general/issue38253c.dart:8:3: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+  int f3() {}
+  ^" in null;
+  }
+  function f4() → asy::Future<core::int> async {
+    return invalid-expression "pkg/front_end/testcases/general/issue38253c.dart:9:3: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+  Future<int> f4() async {}
+  ^" in null;
+  }
+};
+static field (dynamic) → asy::Future<dynamic> b = (dynamic f) → asy::Future<dynamic> async => await f;
+static field (dynamic) → dynamic c = (dynamic f) → dynamic => f;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue38812.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue38812.dart.weak.modular.expect
new file mode 100644
index 0000000..1bcd793
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue38812.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef G<unrelated X extends core::Object* = dynamic> = () →* void;
+class A<X extends () →* void, Y extends () →* void> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*, self::A::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::A::•<() →* void, () →* void>();
+}
diff --git a/pkg/front_end/testcases/general/issue38938.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue38938.dart.weak.modular.expect
new file mode 100644
index 0000000..2ed9c3f
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue38938.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue38938.dart:7:7: Error: 'v' is already declared in this scope.
+//   int v;
+//       ^
+// pkg/front_end/testcases/general/issue38938.dart:6:7: Context: Previous declaration of 'v'.
+//   int v;
+//       ^
+//
+// pkg/front_end/testcases/general/issue38938.dart:8:10: Error: Can't use 'v' because it is declared more than once.
+//   A(this.v);
+//          ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* v = null;
+  constructor •(core::int* v) → self::A*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/issue38938.dart:8:10: Error: Can't use 'v' because it is declared more than once.
+  A(this.v);
+         ^"
+    ;
+  constructor second() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/general/issue38943.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue38943.dart.weak.modular.expect
new file mode 100644
index 0000000..c723406
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue38943.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class D<X extends () →* void> extends core::Object {
+  constructor _() → self::D<self::D::X*>*
+    : super core::Object::•() {}
+  static factory foo<X extends () →* void>() → self::D<self::D::foo::X*>*
+    return new self::D::_<self::D::foo::X*>();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::print(self::D::foo<() →* void>());
+}
diff --git a/pkg/front_end/testcases/general/issue38944.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue38944.dart.weak.modular.expect
new file mode 100644
index 0000000..6ac58de
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue38944.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue38944.dart:6:7: Error: Can't use implicitly 'out' variable 'X' in an 'inout' position in supertype 'A'.
+// class B<X> extends Object with A<void Function<Y extends X>()> {}
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<Q extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::Q*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _B&Object&A<X extends core::Object* = dynamic> extends core::Object /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_B&Object&A<self::_B&Object&A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<X extends core::Object* = dynamic> extends self::_B&Object&A<self::B::X*> {
+  synthetic constructor •() → self::B<self::B::X*>*
+    : super self::_B&Object&A::•()
+    ;
+}
diff --git a/pkg/front_end/testcases/general/issue38961.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue38961.dart.weak.modular.expect
new file mode 100644
index 0000000..a588600
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue38961.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue38961.dart:7:7: Error: 'x' is already declared in this scope.
+//   var x = this;
+//       ^
+// pkg/front_end/testcases/general/issue38961.dart:6:11: Context: Previous declaration of 'x'.
+//   dynamic x = this;
+//           ^
+//
+// pkg/front_end/testcases/general/issue38961.dart:6:15: Error: Can't access 'this' in a field initializer.
+//   dynamic x = this;
+//               ^^^^
+//
+// pkg/front_end/testcases/general/issue38961.dart:7:11: Error: Can't access 'this' in a field initializer.
+//   var x = this;
+//           ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field dynamic x = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/general/issue39344.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue39344.dart.weak.modular.expect
new file mode 100644
index 0000000..fd2787d
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue39344.dart.weak.modular.expect
@@ -0,0 +1,116 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue39344.dart:19:12: Error: A value of type 'List<T>' can't be assigned to a variable of type 'List<B>'.
+//  - 'List' is from 'dart:core'.
+//  - 'B' is from 'pkg/front_end/testcases/general/issue39344.dart'.
+//       xs = ys;
+//            ^
+//
+// pkg/front_end/testcases/general/issue39344.dart:31:13: Error: A value of type 'List<List<T>>' can't be assigned to a variable of type 'List<List<B>>'.
+//  - 'List' is from 'dart:core'.
+//  - 'B' is from 'pkg/front_end/testcases/general/issue39344.dart'.
+//       xss = yss;
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class Class<T extends self::A*> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::T*>*
+    : super core::Object::•()
+    ;
+  method method1a(covariant-by-class self::Class::T* t) → void {
+    if(t is self::B*) {
+      core::List<self::Class::T*>* ys = <self::Class::T*>[t{self::Class::T* & self::B* /* '*' & '*' = '*' */}];
+      self::xs = invalid-expression "pkg/front_end/testcases/general/issue39344.dart:19:12: Error: A value of type 'List<T>' can't be assigned to a variable of type 'List<B>'.
+ - 'List' is from 'dart:core'.
+ - 'B' is from 'pkg/front_end/testcases/general/issue39344.dart'.
+      xs = ys;
+           ^" in ys as{TypeError} core::List<self::B*>*;
+    }
+  }
+  method method1b(covariant-by-class self::Class::T* t) → void {
+    if(t is self::B*) {
+      core::List<core::List<self::Class::T*>*>* yss = <core::List<self::Class::T*>*>[<self::Class::T*>[t{self::Class::T* & self::B* /* '*' & '*' = '*' */}]];
+      self::xss = invalid-expression "pkg/front_end/testcases/general/issue39344.dart:31:13: Error: A value of type 'List<List<T>>' can't be assigned to a variable of type 'List<List<B>>'.
+ - 'List' is from 'dart:core'.
+ - 'B' is from 'pkg/front_end/testcases/general/issue39344.dart'.
+      xss = yss;
+            ^" in yss as{TypeError} core::List<core::List<self::B*>*>*;
+    }
+  }
+  method method2a(covariant-by-class self::Class::T* t) → void {
+    dynamic alias;
+    if(t is self::B*) {
+      core::List<self::Class::T*>* ys = <self::Class::T*>[t{self::Class::T* & self::B* /* '*' & '*' = '*' */}];
+      alias = ys;
+      self::xs = alias as{TypeError,ForDynamic} core::List<self::B*>*;
+    }
+  }
+  method method2b(covariant-by-class self::Class::T* t) → void {
+    dynamic alias;
+    if(t is self::B*) {
+      core::List<core::List<self::Class::T*>*>* yss = <core::List<self::Class::T*>*>[<self::Class::T*>[t{self::Class::T* & self::B* /* '*' & '*' = '*' */}]];
+      alias = yss;
+      self::xss = alias as{TypeError,ForDynamic} core::List<core::List<self::B*>*>*;
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::List<self::B*>* xs;
+static field core::List<core::List<self::B*>*>* xss;
+static method main() → void {
+  self::throws(() → Null {
+    new self::Class::•<self::A*>().{self::Class::method2a}(new self::B::•()){(self::A*) →* void};
+    core::print(self::xs.{core::Object::runtimeType}{core::Type*});
+  });
+  self::throws(() → Null {
+    new self::Class::•<self::A*>().{self::Class::method2b}(new self::B::•()){(self::A*) →* void};
+    core::print(self::xs.{core::Object::runtimeType}{core::Type*});
+  });
+}
+static method errors() → void {
+  new self::Class::•<self::A*>().{self::Class::method1a}(new self::B::•()){(self::A*) →* void};
+  new self::Class::•<self::A*>().{self::Class::method1b}(new self::B::•()){(self::A*) →* void};
+}
+static method throws(() →* void f) → void {
+  try {
+    f(){() →* void};
+  }
+  on dynamic catch(final dynamic e) {
+    core::print(e);
+    return;
+  }
+  throw "Expected throws";
+}
diff --git a/pkg/front_end/testcases/general/issue39421.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue39421.dart.weak.modular.expect
new file mode 100644
index 0000000..cb1d71a
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue39421.dart.weak.modular.expect
@@ -0,0 +1,78 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue39421.dart:9:7: Error: 'A' is already declared in this scope.
+// class A {}
+//       ^
+// pkg/front_end/testcases/general/issue39421.dart:7:7: Context: Previous declaration of 'A'.
+// class A {}
+//       ^
+//
+// pkg/front_end/testcases/general/issue39421.dart:16:12: Error: 'A' isn't a type.
+//   foo(List<A> a) {}
+//            ^
+// pkg/front_end/testcases/general/issue39421.dart:16:12: Context: This isn't a type.
+//   foo(List<A> a) {}
+//            ^
+//
+// pkg/front_end/testcases/general/issue39421.dart:16:12: Error: Can't use 'A' because it is declared more than once.
+//   foo(List<A> a) {}
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A#1 extends core::Object {
+  synthetic constructor •() → self::A#1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method foo(core::List<Null>* a) → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  method foo(core::List<invalid-type>* a) → dynamic {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue39817.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue39817.dart.weak.modular.expect
new file mode 100644
index 0000000..cad4f51
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue39817.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library;
+import self as self;
+
+static method foo() → dynamic {
+  Null _null;
+  for (dynamic i in _null) {
+  }
+  ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue40242.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue40242.dart.weak.modular.expect
new file mode 100644
index 0000000..69ece96a
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue40242.dart.weak.modular.expect
@@ -0,0 +1,70 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue40242.dart:9:5: Error: Can't assign to 'this'.
+//     this = new C();
+//     ^^^^
+//
+// pkg/front_end/testcases/general/issue40242.dart:15:3: Error: Can't assign to the final variable 'c1'.
+//   c1 = new C();
+//   ^^
+//
+// pkg/front_end/testcases/general/issue40242.dart:16:3: Error: Can't assign to a type literal.
+//   C = Object;
+//   ^
+//
+// pkg/front_end/testcases/general/issue40242.dart:18:6: Error: Can't assign to a parenthesized expression.
+//   (c2) = new C();
+//      ^
+//
+// pkg/front_end/testcases/general/issue40242.dart:20:3: Error: Can't assign to the const variable 'c3'.
+//   c3 = null;
+//   ^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension E on self::C* {
+  method errors = self::E|errors;
+  tearoff errors = self::E|get#errors;
+}
+static method E|errors(lowered final self::C* #this) → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/issue40242.dart:9:5: Error: Can't assign to 'this'.
+    this = new C();
+    ^^^^";
+}
+static method E|get#errors(lowered final self::C* #this) → () →* dynamic
+  return () → dynamic => self::E|errors(#this);
+static method errors() → dynamic {
+  final self::C* c1 = new self::C::•();
+  invalid-expression "pkg/front_end/testcases/general/issue40242.dart:15:3: Error: Can't assign to the final variable 'c1'.
+  c1 = new C();
+  ^^";
+  invalid-expression "pkg/front_end/testcases/general/issue40242.dart:16:3: Error: Can't assign to a type literal.
+  C = Object;
+  ^";
+  self::C* c2;
+  invalid-expression "pkg/front_end/testcases/general/issue40242.dart:18:6: Error: Can't assign to a parenthesized expression.
+  (c2) = new C();
+     ^";
+  invalid-expression "pkg/front_end/testcases/general/issue40242.dart:20:3: Error: Can't assign to the const variable 'c3'.
+  c3 = null;
+  ^^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue40428.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue40428.dart.weak.modular.expect
new file mode 100644
index 0000000..d89d308
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue40428.dart.weak.modular.expect
@@ -0,0 +1,84 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue40428.dart:28:19: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+//   new NamedMixin1(0);
+//                   ^
+//
+// pkg/front_end/testcases/general/issue40428.dart:29:19: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+//   new NamedMixin2(0);
+//                   ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class SuperClass1 extends core::Object {
+  final field core::String* value;
+  constructor •(core::String* value) → self::SuperClass1*
+    : self::SuperClass1::value = value, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class SuperClass2 extends core::Object {
+  final field core::String* value;
+  constructor •(core::String* i) → self::SuperClass2*
+    : self::SuperClass2::value = i, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Mixin extends core::Object {
+  synthetic constructor •() → self::Mixin*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class NamedMixin1 = self::SuperClass1 with self::Mixin {
+  synthetic constructor •(core::String* value) → self::NamedMixin1*
+    : super self::SuperClass1::•(value)
+    ;
+}
+class NamedMixin2 = self::SuperClass2 with self::Mixin {
+  synthetic constructor •(core::String* i) → self::NamedMixin2*
+    : super self::SuperClass2::•(i)
+    ;
+}
+static method main() → void {
+  new self::NamedMixin1::•("");
+  new self::NamedMixin2::•("");
+}
+static method errors() → dynamic {
+  new self::NamedMixin1::•(invalid-expression "pkg/front_end/testcases/general/issue40428.dart:28:19: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+  new NamedMixin1(0);
+                  ^" in 0 as{TypeError} core::String*);
+  new self::NamedMixin2::•(invalid-expression "pkg/front_end/testcases/general/issue40428.dart:29:19: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+  new NamedMixin2(0);
+                  ^" in 0 as{TypeError} core::String*);
+}
diff --git a/pkg/front_end/testcases/general/issue40662.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue40662.dart.weak.modular.expect
new file mode 100644
index 0000000..dc6a6d8
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue40662.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method bar(core::int* a, core::List<core::int*>* b) → dynamic {
+  self::expect(1.{core::int::unary-}(){() →* core::int*}, a);
+  self::expect(1.{core::int::unary-}(){() →* core::int*}, b.{core::List::[]}(0){(core::int*) →* core::int*}.{core::num::-}(2){(core::num*) →* core::int*});
+}
+static method foo(core::int* x) → dynamic async 
+  return self::bar(x.{core::num::-}(1){(core::num*) →* core::int*}, !(x == null) ?{core::List<core::int*>*} <core::int*>[x.{core::num::+}(1){(core::num*) →* core::int*}, x.{core::num::+}(2){(core::num*) →* core::int*}, await null] : null);
+static method main() → void async 
+  return await self::foo(0);
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/general/issue40744.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue40744.dart.weak.modular.expect
new file mode 100644
index 0000000..cab8593
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue40744.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static const field core::Map<core::String*, dynamic>* generatorConfigDefaultJson = #C3;
+static method helper(core::Map<core::String*, dynamic>* input) → void {
+  core::print(input);
+}
+static method main() → void {
+  final core::Map<core::String*, Null>* nullValueMap = core::Map::fromEntries<core::String*, Null>(#C3.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, dynamic>*>*}.{core::Iterable::map}<core::MapEntry<core::String*, Null>*>((core::MapEntry<core::String*, dynamic>* e) → core::MapEntry<core::String*, Null>* => new core::MapEntry::_<core::String*, Null>(e.{core::MapEntry::key}{core::String*}, null)){((core::MapEntry<core::String*, dynamic>*) →* core::MapEntry<core::String*, Null>*) →* core::Iterable<core::MapEntry<core::String*, Null>*>*});
+  self::helper(nullValueMap);
+}
+
+constants  {
+  #C1 = "a"
+  #C2 = 1
+  #C3 = <core::String*, dynamic>{#C1:#C2)
+}
diff --git a/pkg/front_end/testcases/general/issue40982.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue40982.dart.weak.modular.expect
new file mode 100644
index 0000000..9eb651c
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue40982.dart.weak.modular.expect
@@ -0,0 +1,109 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue40982.dart:28:9: Error: A constant constructor can't call a non-constant super constructor.
+//   const E1();
+//         ^
+//
+// pkg/front_end/testcases/general/issue40982.dart:34:9: Error: A constant constructor can't call a non-constant super constructor.
+//   const E3();
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object /*isMixinDeclaration*/  {
+  static const field core::int* value = #C1;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C1&A&B = self::A with self::B /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C1&A&B*
+    : super self::A::•()
+    ;
+}
+class C1 extends self::_C1&A&B /*hasConstConstructor*/  {
+  const constructor •() → self::C1*
+    : super self::_C1&A&B::•()
+    ;
+}
+class C2 = self::A with self::B /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::C2*
+    : super self::A::•()
+    ;
+}
+class C3 extends self::C2 /*hasConstConstructor*/  {
+  const constructor •() → self::C3*
+    : super self::C2::•()
+    ;
+}
+abstract class D extends core::Object /*isMixinDeclaration*/  {
+  field core::int* value = 1;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _E1&A&D = self::A with self::D /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_E1&A&D*
+    : super self::A::•()
+    ;
+  mixin-super-stub get value() → core::int*
+    return super.{self::D::value};
+  mixin-super-stub set value(core::int* value) → void
+    return super.{self::D::value} = value;
+}
+class E1 extends self::_E1&A&D /*hasConstConstructor*/  {
+  const constructor •() → self::E1*
+    : super self::_E1&A&D::•()
+    ;
+}
+class E2 = self::A with self::D {
+  synthetic constructor •() → self::E2*
+    : super self::A::•()
+    ;
+  mixin-super-stub get value() → core::int*
+    return super.{self::D::value};
+  mixin-super-stub set value(core::int* value) → void
+    return super.{self::D::value} = value;
+}
+class E3 extends self::E2 /*hasConstConstructor*/  {
+  const constructor •() → self::E3*
+    : super self::E2::•()
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 1
+}
diff --git a/pkg/front_end/testcases/general/issue41070.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue41070.dart.weak.modular.expect
new file mode 100644
index 0000000..d159c73
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue41070.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class Mixin extends core::Object {
+  synthetic constructor •() → self::Mixin*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Base extends core::Object /*hasConstConstructor*/  {
+  final field core::int* x;
+  const constructor •(core::int* x) → self::Base*
+    : self::Base::x = x, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Application = self::Base with self::Mixin /*hasConstConstructor*/  {
+  const synthetic constructor •(core::int* x) → self::Application*
+    : super self::Base::•(x)
+    ;
+}
+static method main() → dynamic {
+  self::expect(42, #C2.{self::Base::x}{core::int*});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = 42
+  #C2 = self::Application {x:#C1}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue41070.dart:
+- Application. (from org-dartlang-testcase:///issue41070.dart:12:7)
+- Base. (from org-dartlang-testcase:///issue41070.dart:9:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/issue41210a.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue41210a.dart.weak.modular.expect
new file mode 100644
index 0000000..f270273
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue41210a.dart.weak.modular.expect
@@ -0,0 +1,201 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue41210a.dart:23:7: Error: Applying the mixin 'B' to 'Object with A' introduces an erroneous override of 'method'.
+// class C with A, B {} // error
+//       ^
+// pkg/front_end/testcases/general/issue41210a.dart:20:10: Context: The method 'B.method' has fewer named arguments than those of overridden method 'Object with A.method'.
+//   String method(num i);
+//          ^
+// pkg/front_end/testcases/general/issue41210a.dart:23:7: Context: This is the overridden method ('method').
+// class C with A, B {} // error
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  synthetic constructor •() → self::Interface*
+    : super core::Object::•()
+    ;
+  abstract method method(core::num* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Interface2 extends core::Object {
+  synthetic constructor •() → self::Interface2*
+    : super core::Object::•()
+    ;
+  abstract method method(covariant-by-declaration core::int* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class A extends core::Object implements self::Interface /*isMixinDeclaration*/  {
+  method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return s;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object implements self::Interface {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract method method(core::num* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&Object&A = core::Object with self::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{self::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&Object&A&B = self::_C&Object&A with self::B /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A&B*
+    : super self::_C&Object&A::•()
+    ;
+  abstract mixin-stub method method(core::num* i) → core::String*; -> self::B::method
+}
+class C extends self::_C&Object&A&B {
+  synthetic constructor •() → self::C*
+    : super self::_C&Object&A&B::•()
+    ;
+}
+abstract class D extends core::Object implements self::Interface, self::Interface2 {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract forwarding-stub method method(covariant-by-declaration core::num* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _E&Object&A = core::Object with self::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{self::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _E&Object&A&D = self::_E&Object&A with self::D /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E&Object&A&D*
+    : super self::_E&Object&A::•()
+    ;
+  forwarding-stub method method(covariant-by-declaration core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{self::_E&Object&A::method}(i, s: s);
+}
+class E extends self::_E&Object&A&D {
+  synthetic constructor •() → self::E*
+    : super self::_E&Object&A&D::•()
+    ;
+}
+abstract class F extends core::Object implements self::Interface {
+  synthetic constructor •() → self::F*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _G&Object&A = core::Object with self::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_G&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{self::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _G&Object&A&F = self::_G&Object&A with self::F /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_G&Object&A&F*
+    : super self::_G&Object&A::•()
+    ;
+}
+class G extends self::_G&Object&A&F {
+  synthetic constructor •() → self::G*
+    : super self::_G&Object&A&F::•()
+    ;
+}
+static method main() → dynamic {
+  core::print(new self::C::•().{self::_C&Object&A&B::method}(0){(core::num*) →* core::String*});
+}
+
+constants  {
+  #C1 = "hello"
+}
diff --git a/pkg/front_end/testcases/general/issue41210a_no_error.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue41210a_no_error.dart.weak.modular.expect
new file mode 100644
index 0000000..daf4b8e
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue41210a_no_error.dart.weak.modular.expect
@@ -0,0 +1,158 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  synthetic constructor •() → self::Interface*
+    : super core::Object::•()
+    ;
+  abstract method method(core::num* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Interface2 extends core::Object {
+  synthetic constructor •() → self::Interface2*
+    : super core::Object::•()
+    ;
+  abstract method method(covariant-by-declaration core::int* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class A extends core::Object implements self::Interface /*isMixinDeclaration*/  {
+  method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return s;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object implements self::Interface {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract method method(core::num* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D extends core::Object implements self::Interface, self::Interface2 {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract forwarding-stub method method(covariant-by-declaration core::num* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _E&Object&A = core::Object with self::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{self::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _E&Object&A&D = self::_E&Object&A with self::D /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E&Object&A&D*
+    : super self::_E&Object&A::•()
+    ;
+  forwarding-stub method method(covariant-by-declaration core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{self::_E&Object&A::method}(i, s: s);
+}
+class E extends self::_E&Object&A&D {
+  synthetic constructor •() → self::E*
+    : super self::_E&Object&A&D::•()
+    ;
+}
+abstract class F extends core::Object implements self::Interface {
+  synthetic constructor •() → self::F*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _G&Object&A = core::Object with self::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_G&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{self::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _G&Object&A&F = self::_G&Object&A with self::F /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_G&Object&A&F*
+    : super self::_G&Object&A::•()
+    ;
+}
+class G extends self::_G&Object&A&F {
+  synthetic constructor •() → self::G*
+    : super self::_G&Object&A&F::•()
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = "hello"
+}
diff --git a/pkg/front_end/testcases/general/issue41210b/issue41210.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue41210b/issue41210.dart.weak.modular.expect
new file mode 100644
index 0000000..d12bb3b
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue41210b/issue41210.dart.weak.modular.expect
@@ -0,0 +1,111 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue41210b/issue41210.dart:9:7: Error: Applying the mixin 'B' to 'Object with A' introduces an erroneous override of 'method'.
+// class C with A, B {} // error
+//       ^
+// pkg/front_end/testcases/general/issue41210b/issue41210_lib.dart:20:10: Context: The method 'B.method' has fewer named arguments than those of overridden method 'Object with A.method'.
+//   String method(num i);
+//          ^
+// pkg/front_end/testcases/general/issue41210b/issue41210.dart:9:7: Context: This is the overridden method ('method').
+// class C with A, B {} // error
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+import "issue41210_lib.dart" as iss;
+
+import "org-dartlang-testcase:///issue41210_lib.dart";
+
+abstract class _C&Object&A = core::Object with iss::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{iss::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&Object&A&B = self::_C&Object&A with iss::B /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A&B*
+    : super self::_C&Object&A::•()
+    ;
+  abstract mixin-stub method method(core::num* i) → core::String*; -> iss::B::method
+}
+class C extends self::_C&Object&A&B {
+  synthetic constructor •() → self::C*
+    : super self::_C&Object&A&B::•()
+    ;
+}
+abstract class _E&Object&A = core::Object with iss::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E&Object&A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{iss::A::method}(i, s: s);
+}
+abstract class _E&Object&A&D = self::_E&Object&A with iss::D /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E&Object&A&D*
+    : super self::_E&Object&A::•()
+    ;
+  forwarding-stub method method(covariant-by-declaration core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{self::_E&Object&A::method}(i, s: s);
+}
+class E extends self::_E&Object&A&D {
+  synthetic constructor •() → self::E*
+    : super self::_E&Object&A&D::•()
+    ;
+}
+abstract class _G&Object&A = core::Object with iss::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_G&Object&A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{iss::A::method}(i, s: s);
+}
+abstract class _G&Object&A&F = self::_G&Object&A with iss::F /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_G&Object&A&F*
+    : super self::_G&Object&A::•()
+    ;
+}
+class G extends self::_G&Object&A&F {
+  synthetic constructor •() → self::G*
+    : super self::_G&Object&A&F::•()
+    ;
+}
+static method main() → dynamic {
+  core::print(new self::C::•().{self::_C&Object&A&B::method}(0){(core::num*) →* core::String*});
+}
+
+constants  {
+  #C1 = "hello"
+}
diff --git a/pkg/front_end/testcases/general/issue41210b/issue41210.no_link.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue41210b/issue41210.no_link.dart.weak.modular.expect
new file mode 100644
index 0000000..038d724
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue41210b/issue41210.no_link.dart.weak.modular.expect
@@ -0,0 +1,209 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue41210b/issue41210.no_link.dart:7:7: Error: Applying the mixin 'B' to 'Object with A' introduces an erroneous override of 'method'.
+// class C with A, B {} // error
+//       ^
+// pkg/front_end/testcases/general/issue41210b/issue41210_lib.dart:20:10: Context: The method 'B.method' has fewer named arguments than those of overridden method 'Object with A.method'.
+//   String method(num i);
+//          ^
+// pkg/front_end/testcases/general/issue41210b/issue41210.no_link.dart:7:7: Context: This is the overridden method ('method').
+// class C with A, B {} // error
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+import "issue41210_lib.dart" as iss;
+
+import "org-dartlang-testcase:///issue41210_lib.dart";
+
+abstract class _C&Object&A = core::Object with iss::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{iss::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&Object&A&B = self::_C&Object&A with iss::B /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A&B*
+    : super self::_C&Object&A::•()
+    ;
+  abstract mixin-stub method method(core::num* i) → core::String*; -> iss::B::method
+}
+class C extends self::_C&Object&A&B {
+  synthetic constructor •() → self::C*
+    : super self::_C&Object&A&B::•()
+    ;
+}
+abstract class _E&Object&A = core::Object with iss::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{iss::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _E&Object&A&D = self::_E&Object&A with iss::D /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E&Object&A&D*
+    : super self::_E&Object&A::•()
+    ;
+  forwarding-stub method method(covariant-by-declaration core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{self::_E&Object&A::method}(i, s: s);
+}
+class E extends self::_E&Object&A&D {
+  synthetic constructor •() → self::E*
+    : super self::_E&Object&A&D::•()
+    ;
+}
+abstract class _G&Object&A = core::Object with iss::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_G&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{iss::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _G&Object&A&F = self::_G&Object&A with iss::F /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_G&Object&A&F*
+    : super self::_G&Object&A::•()
+    ;
+}
+class G extends self::_G&Object&A&F {
+  synthetic constructor •() → self::G*
+    : super self::_G&Object&A&F::•()
+    ;
+}
+static method main() → dynamic {
+  core::print(new self::C::•().{self::_C&Object&A&B::method}(0){(core::num*) →* core::String*});
+}
+
+library;
+import self as iss;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  synthetic constructor •() → iss::Interface*
+    : super core::Object::•()
+    ;
+  abstract method method(core::num* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Interface2 extends core::Object {
+  synthetic constructor •() → iss::Interface2*
+    : super core::Object::•()
+    ;
+  abstract method method(covariant-by-declaration core::int* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class A extends core::Object implements iss::Interface /*isMixinDeclaration*/  {
+  method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return s;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object implements iss::Interface {
+  synthetic constructor •() → iss::B*
+    : super core::Object::•()
+    ;
+  abstract method method(core::num* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D extends core::Object implements iss::Interface, iss::Interface2 {
+  synthetic constructor •() → iss::D*
+    : super core::Object::•()
+    ;
+  abstract forwarding-stub method method(covariant-by-declaration core::num* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class F extends core::Object implements iss::Interface {
+  synthetic constructor •() → iss::F*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+constants  {
+  #C1 = "hello"
+}
diff --git a/pkg/front_end/testcases/general/issue41210b/issue41210_no_error.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue41210b/issue41210_no_error.dart.weak.modular.expect
new file mode 100644
index 0000000..20cd047
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue41210b/issue41210_no_error.dart.weak.modular.expect
@@ -0,0 +1,68 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "issue41210_lib.dart" as iss;
+
+import "org-dartlang-testcase:///issue41210_lib.dart";
+
+abstract class _E&Object&A = core::Object with iss::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E&Object&A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{iss::A::method}(i, s: s);
+}
+abstract class _E&Object&A&D = self::_E&Object&A with iss::D /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E&Object&A&D*
+    : super self::_E&Object&A::•()
+    ;
+  forwarding-stub method method(covariant-by-declaration core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{self::_E&Object&A::method}(i, s: s);
+}
+class E extends self::_E&Object&A&D {
+  synthetic constructor •() → self::E*
+    : super self::_E&Object&A&D::•()
+    ;
+}
+abstract class _G&Object&A = core::Object with iss::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_G&Object&A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{iss::A::method}(i, s: s);
+}
+abstract class _G&Object&A&F = self::_G&Object&A with iss::F /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_G&Object&A&F*
+    : super self::_G&Object&A::•()
+    ;
+}
+class G extends self::_G&Object&A&F {
+  synthetic constructor •() → self::G*
+    : super self::_G&Object&A&F::•()
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = "hello"
+}
diff --git a/pkg/front_end/testcases/general/issue41210b/issue41210_no_error.no_link.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue41210b/issue41210_no_error.no_link.dart.weak.modular.expect
new file mode 100644
index 0000000..cf99014
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue41210b/issue41210_no_error.no_link.dart.weak.modular.expect
@@ -0,0 +1,166 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "issue41210_lib.dart" as iss;
+
+import "org-dartlang-testcase:///issue41210_lib.dart";
+
+abstract class _E&Object&A = core::Object with iss::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{iss::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _E&Object&A&D = self::_E&Object&A with iss::D /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E&Object&A&D*
+    : super self::_E&Object&A::•()
+    ;
+  forwarding-stub method method(covariant-by-declaration core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{self::_E&Object&A::method}(i, s: s);
+}
+class E extends self::_E&Object&A&D {
+  synthetic constructor •() → self::E*
+    : super self::_E&Object&A&D::•()
+    ;
+}
+abstract class _G&Object&A = core::Object with iss::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_G&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{iss::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _G&Object&A&F = self::_G&Object&A with iss::F /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_G&Object&A&F*
+    : super self::_G&Object&A::•()
+    ;
+}
+class G extends self::_G&Object&A&F {
+  synthetic constructor •() → self::G*
+    : super self::_G&Object&A&F::•()
+    ;
+}
+static method main() → dynamic {}
+
+library;
+import self as iss;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  synthetic constructor •() → iss::Interface*
+    : super core::Object::•()
+    ;
+  abstract method method(core::num* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Interface2 extends core::Object {
+  synthetic constructor •() → iss::Interface2*
+    : super core::Object::•()
+    ;
+  abstract method method(covariant-by-declaration core::int* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class A extends core::Object implements iss::Interface /*isMixinDeclaration*/  {
+  method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return s;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object implements iss::Interface {
+  synthetic constructor •() → iss::B*
+    : super core::Object::•()
+    ;
+  abstract method method(core::num* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D extends core::Object implements iss::Interface, iss::Interface2 {
+  synthetic constructor •() → iss::D*
+    : super core::Object::•()
+    ;
+  abstract forwarding-stub method method(covariant-by-declaration core::num* i) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class F extends core::Object implements iss::Interface {
+  synthetic constructor •() → iss::F*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+constants  {
+  #C1 = "hello"
+}
diff --git a/pkg/front_end/testcases/general/issue41252.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue41252.dart.weak.modular.expect
new file mode 100644
index 0000000..6d313f3
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue41252.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue41252.dart:7:20: Error: 'X' is already declared in this scope.
+//   static final int X = 0;
+//                    ^
+// pkg/front_end/testcases/general/issue41252.dart:6:20: Context: Previous declaration of 'X'.
+//   static final int X = 0;
+//                    ^
+//
+// pkg/front_end/testcases/general/issue41252.dart:9:26: Error: Can't use 'X' because it is declared more than once.
+//   static final int foo = X + 1;
+//                          ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  static final field core::int X = null;
+  static final field core::int foo = invalid-expression "pkg/front_end/testcases/general/issue41252.dart:9:26: Error: Can't use 'X' because it is declared more than once.
+  static final int foo = X + 1;
+                         ^"{<invalid>}.+(1);
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue42435.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue42435.dart.weak.modular.expect
new file mode 100644
index 0000000..3dd8dc5
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue42435.dart.weak.modular.expect
@@ -0,0 +1,190 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue42435.dart:7:22: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+// typedef F = Function<Y extends A>();
+//                      ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:10:14: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+//   B(Function<Z extends A>() a);
+//              ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:11:26: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+//   factory B.foo(Function<Z extends A>() a) => new B(a);
+//                          ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:12:17: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+//   foo2(Function<Z extends A>() a) {}
+//                 ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:13:12: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+//   Function<Z extends A>() foo3() => throw 42;
+//            ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:14:12: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+//   Function<Z extends A>() get foo4 => throw 42;
+//            ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:16:12: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+//   Function<Z extends A>() foo6 = (() => throw 42)();
+//            ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:15:26: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+//   void set foo5(Function<Z extends A>() a) {}
+//                          ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:19:15: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+// bar2(Function<Z extends A>() a) {}
+//               ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:20:10: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+// Function<Z extends A>() bar3() => throw 42;
+//          ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:21:10: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+// Function<Z extends A>() get bar4 => throw 42;
+//          ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:23:10: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+// Function<Z extends A>() bar6 = (() => throw 42)();
+//          ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:26:17: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+//   baz2(Function<Z extends A>() a) {}
+//                 ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:27:12: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+//   Function<Z extends A>() baz3() => throw 42;
+//            ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:28:12: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+//   Function<Z extends A>() get baz4 => throw 42;
+//            ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:29:26: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+//   void set baz5(Function<Z extends A>() a) {}
+//                          ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue42435.dart:22:24: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+// void set bar5(Function<Z extends A>() a) {}
+//                        ^
+// pkg/front_end/testcases/general/issue42435.dart:5:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+typedef F = <Y extends self::A<self::A<dynamic>> = dynamic>() → dynamic;
+class A<X extends self::A<self::A::X> = self::A<dynamic>> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X>
+    : super core::Object::•()
+    ;
+}
+class B extends core::Object {
+  field <Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic foo6 = let final Never #t1 = (() → Never => throw 42)(){() → Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  constructor •(<Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic a) → self::B
+    : super core::Object::•()
+    ;
+  static factory foo(<Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic a) → self::B
+    return new self::B::•(a);
+  method foo2(<Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic a) → dynamic {}
+  method foo3() → <Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic
+    return throw 42;
+  get foo4() → <Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic
+    return throw 42;
+  set foo5(<Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic a) → void {}
+}
+extension E on core::int {
+  method baz2 = self::E|baz2;
+  tearoff baz2 = self::E|get#baz2;
+  method baz3 = self::E|baz3;
+  tearoff baz3 = self::E|get#baz3;
+  get baz4 = self::E|get#baz4;
+  set baz5 = self::E|set#baz5;
+}
+static field <Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic bar6 = let final Never #t2 = (() → Never => throw 42)(){() → Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+static method bar2(<Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic a) → dynamic {}
+static method bar3() → <Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic
+  return throw 42;
+static get bar4() → <Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic
+  return throw 42;
+static set bar5(<Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic a) → void {}
+static method E|baz2(lowered final core::int #this, <Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic a) → dynamic {}
+static method E|get#baz2(lowered final core::int #this) → (<Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic) → dynamic
+  return (<Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic a) → dynamic => self::E|baz2(#this, a);
+static method E|baz3(lowered final core::int #this) → <Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic
+  return throw 42;
+static method E|get#baz3(lowered final core::int #this) → () → <Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic
+  return () → <Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic => self::E|baz3(#this);
+static method E|get#baz4(lowered final core::int #this) → <Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic
+  return throw 42;
+static method E|set#baz5(lowered final core::int #this, <Z extends self::A<self::A<dynamic>> = dynamic>() → dynamic a) → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue42435_2.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue42435_2.dart.weak.modular.expect
new file mode 100644
index 0000000..aa9fc93
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue42435_2.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue42435_2.dart:3:27: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+// typedef AAlias = Function<X extends A>();
+//                           ^
+// pkg/front_end/testcases/general/issue42435_2.dart:1:9: Context: Bound of this variable references variable 'X' from the same declaration.
+// class A<X extends A<X>> {}
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef AAlias = <X extends self::A<self::A<dynamic>> = dynamic>() → dynamic;
+class A<X extends self::A<self::A::X> = self::A<dynamic>> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X>
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue42610.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue42610.dart.weak.modular.expect
new file mode 100644
index 0000000..44db974
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue42610.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue42610.dart:6:4: Error: 'final' can't be used as an identifier because it's a keyword.
+// Try renaming this to be an identifier that isn't a keyword.
+//   #final;
+//    ^^^^^
+//
+// pkg/front_end/testcases/general/issue42610.dart:7:9: Error: The final variable 'x' must be initialized.
+// Try adding an initializer ('= expression') to the declaration.
+//   final x;
+//         ^
+//
+// pkg/front_end/testcases/general/issue42610.dart:8:9: Error: The const variable 'y' must be initialized.
+// Try adding an initializer ('= expression') to the declaration.
+//   const y;
+//         ^
+//
+// pkg/front_end/testcases/general/issue42610.dart:9:13: Error: The final variable 'z' must be initialized.
+// Try adding an initializer ('= expression') to the declaration.
+//   final int z;
+//             ^
+//
+// pkg/front_end/testcases/general/issue42610.dart:10:13: Error: The const variable 'w' must be initialized.
+// Try adding an initializer ('= expression') to the declaration.
+//   const int w;
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  #C1;
+  final invalid-type x = invalid-expression "pkg/front_end/testcases/general/issue42610.dart:7:9: Error: The final variable 'x' must be initialized.
+Try adding an initializer ('= expression') to the declaration.
+  final x;
+        ^";
+  const invalid-type y = invalid-expression "pkg/front_end/testcases/general/issue42610.dart:8:9: Error: The const variable 'y' must be initialized.
+Try adding an initializer ('= expression') to the declaration.
+  const y;
+        ^";
+  final core::int* z = invalid-expression "pkg/front_end/testcases/general/issue42610.dart:9:13: Error: The final variable 'z' must be initialized.
+Try adding an initializer ('= expression') to the declaration.
+  final int z;
+            ^";
+  const core::int* w = invalid-expression "pkg/front_end/testcases/general/issue42610.dart:10:13: Error: The const variable 'w' must be initialized.
+Try adding an initializer ('= expression') to the declaration.
+  const int w;
+            ^";
+}
+static method main() → void {}
+
+constants  {
+  #C1 = #final
+}
diff --git a/pkg/front_end/testcases/general/issue42615.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue42615.dart.weak.modular.expect
new file mode 100644
index 0000000..08aafe4
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue42615.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+class Class<T extends core::Object* = dynamic> extends core::Object {
+  constructor •({() →* FutureOr<core::List<self::Class::T*>*>* a = #C1}) → self::Class<self::Class::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method method() → dynamic
+  return null;
+static method main() → dynamic {
+  new self::Class::•<dynamic>(a: () → FutureOr<core::List<dynamic>*>* async => self::method() as{TypeError} FutureOr<core::List<dynamic>*>*);
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/issue42694.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue42694.dart.weak.modular.expect
new file mode 100644
index 0000000..f8b3fdc
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue42694.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract set setter(core::int* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::A {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  get setter() → core::int*
+    return throw "";
+  set setter(core::int* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue42997.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue42997.dart.weak.modular.expect
new file mode 100644
index 0000000..b11e219
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue42997.dart.weak.modular.expect
@@ -0,0 +1,87 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue42997.dart:9:16: Error: Expected a function body or '=>'.
+// Try adding {}.
+// PropertyState();
+//                ^
+//
+// pkg/front_end/testcases/general/issue42997.dart:10:7: Error: 'PropertyState' is already declared in this scope.
+// class PropertyState<I, O> {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/general/issue42997.dart:9:1: Context: Previous declaration of 'PropertyState'.
+// PropertyState();
+// ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/issue42997.dart:12:10: Error: Can't use 'PropertyState' because it is declared more than once.
+//     for (PropertyState<Object, Object>> state in _states) ;
+//          ^
+//
+// pkg/front_end/testcases/general/issue42997.dart:12:24: Error: Expected ';' after this.
+//     for (PropertyState<Object, Object>> state in _states) ;
+//                        ^^^^^^
+//
+// pkg/front_end/testcases/general/issue42997.dart:12:30: Error: Expected an identifier, but got ','.
+// Try inserting an identifier before ','.
+//     for (PropertyState<Object, Object>> state in _states) ;
+//                              ^
+//
+// pkg/front_end/testcases/general/issue42997.dart:12:47: Error: Unexpected token 'in'.
+//     for (PropertyState<Object, Object>> state in _states) ;
+//                                               ^^
+//
+// pkg/front_end/testcases/general/issue42997.dart:12:41: Error: The getter 'state' isn't defined for the class 'PropertyState#1<I, O>'.
+//  - 'PropertyState#1' is from 'pkg/front_end/testcases/general/issue42997.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'state'.
+//     for (PropertyState<Object, Object>> state in _states) ;
+//                                         ^^^^^
+//
+// pkg/front_end/testcases/general/issue42997.dart:12:38: Error: The operator '>>' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '>>' operator.
+//     for (PropertyState<Object, Object>> state in _states) ;
+//                                      ^^
+//
+import self as self;
+import "dart:core" as core;
+
+class PropertyState#1<I extends core::Object* = dynamic, O extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::PropertyState#1<self::PropertyState#1::I*, self::PropertyState#1::O*>*
+    : super core::Object::•()
+    ;
+  method dispose() → void {
+    for (final invalid-type #t1 = invalid-expression "pkg/front_end/testcases/general/issue42997.dart:12:10: Error: Can't use 'PropertyState' because it is declared more than once.
+    for (PropertyState<Object, Object>> state in _states) ;
+         ^"{<invalid>}.<(#C1); invalid-expression "pkg/front_end/testcases/general/issue42997.dart:12:30: Error: This couldn't be parsed.
+    for (PropertyState<Object, Object>> state in _states) ;
+                             ^"; invalid-expression "pkg/front_end/testcases/general/issue42997.dart:12:30: Error: This couldn't be parsed.
+    for (PropertyState<Object, Object>> state in _states) ;
+                             ^", invalid-expression "pkg/front_end/testcases/general/issue42997.dart:12:38: Error: The operator '>>' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '>>' operator.
+    for (PropertyState<Object, Object>> state in _states) ;
+                                     ^^" in #C1{<unresolved>}.>>(invalid-expression "pkg/front_end/testcases/general/issue42997.dart:12:41: Error: The getter 'state' isn't defined for the class 'PropertyState#1<I, O>'.
+ - 'PropertyState#1' is from 'pkg/front_end/testcases/general/issue42997.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'state'.
+    for (PropertyState<Object, Object>> state in _states) ;
+                                        ^^^^^" in this{<unresolved>}.state))
+      ;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+static abstract method PropertyState() → dynamic;
+
+constants  {
+  #C1 = TypeLiteralConstant(core::Object*)
+}
diff --git a/pkg/front_end/testcases/general/issue43290.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue43290.dart.weak.modular.expect
new file mode 100644
index 0000000..436e5dd
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue43290.dart.weak.modular.expect
@@ -0,0 +1,82 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue43290.dart:15:25: Error: Not a constant expression.
+//     const Class(length: length);
+//                         ^^^^^^
+//
+// pkg/front_end/testcases/general/issue43290.dart:23:15: Error: Not a constant expression.
+//     const a = length;
+//               ^^^^^^
+//
+// pkg/front_end/testcases/general/issue43290.dart:11:11: Error: Constant evaluation error:
+//     const Class(length: this.length);
+//           ^
+// pkg/front_end/testcases/general/issue43290.dart:11:30: Context: Not a constant expression.
+//     const Class(length: this.length);
+//                              ^
+//
+// pkg/front_end/testcases/general/issue43290.dart:15:11: Error: Constant evaluation error:
+//     const Class(length: length);
+//           ^
+// pkg/front_end/testcases/general/issue43290.dart:15:25: Context: Not a constant expression.
+//     const Class(length: length);
+//                         ^
+//
+// pkg/front_end/testcases/general/issue43290.dart:19:20: Error: Constant evaluation error:
+//     const a = this.length;
+//                    ^
+// pkg/front_end/testcases/general/issue43290.dart:19:20: Context: Not a constant expression.
+//     const a = this.length;
+//                    ^
+// pkg/front_end/testcases/general/issue43290.dart:19:11: Context: While analyzing:
+//     const a = this.length;
+//           ^
+//
+// pkg/front_end/testcases/general/issue43290.dart:23:15: Error: Constant evaluation error:
+//     const a = length;
+//               ^
+// pkg/front_end/testcases/general/issue43290.dart:23:15: Context: Not a constant expression.
+//     const a = length;
+//               ^
+// pkg/front_end/testcases/general/issue43290.dart:23:11: Context: While analyzing:
+//     const a = length;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object /*hasConstConstructor*/  {
+  final field core::int* length;
+  const constructor •({core::int* length = #C1}) → self::Class*
+    : self::Class::length = length, super core::Object::•()
+    ;
+  method method1a() → dynamic {
+    invalid-expression "Not a constant expression.";
+  }
+  method method1b() → dynamic {
+    invalid-expression "Not a constant expression.";
+  }
+  method method2a() → dynamic {
+    const core::int* a = invalid-expression "Not a constant expression.";
+  }
+  method method2b() → dynamic {
+    const core::int* a = invalid-expression "Not a constant expression.";
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/issue43363.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue43363.dart.weak.modular.expect
new file mode 100644
index 0000000..b4cfb49
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue43363.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue43363.dart:10:9: Error: Expected a class member, but got 'this'.
+//         this.y = 2;
+//         ^^^^
+//
+// pkg/front_end/testcases/general/issue43363.dart:10:13: Error: Expected a class member, but got '.'.
+//         this.y = 2;
+//             ^
+//
+// pkg/front_end/testcases/general/issue43363.dart:10:14: Error: Variables must be declared using the keywords 'const', 'final', 'var' or a type name.
+// Try adding the name of the type of the variable or the keyword 'var'.
+//         this.y = 2;
+//              ^
+//
+// pkg/front_end/testcases/general/issue43363.dart:10:14: Error: 'y' is already declared in this scope.
+//         this.y = 2;
+//              ^
+// pkg/front_end/testcases/general/issue43363.dart:7:13: Context: Previous declaration of 'y'.
+//   final int y;
+//             ^
+//
+// pkg/front_end/testcases/general/issue43363.dart:9:16: Error: A redirecting constructor can't have other initializers.
+//         this.x = 1;
+//                ^
+//
+// pkg/front_end/testcases/general/issue43363.dart:13:20: Error: Can't use 'y' because it is declared more than once.
+//               this.y = 6;
+//                    ^
+//
+import self as self;
+import "dart:core" as core;
+
+class E extends core::Object {
+  final field core::int* x;
+  final field core::int* y = null;
+  constructor •() → self::E*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/issue43363.dart:9:16: Error: A redirecting constructor can't have other initializers.
+        this.x = 1;
+               ^", this self::E::named()
+    ;
+  constructor named() → self::E*
+    : self::E::x = 5, final dynamic #t2 = invalid-expression "pkg/front_end/testcases/general/issue43363.dart:13:20: Error: Can't use 'y' because it is declared more than once.
+              this.y = 6;
+                   ^"
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue43721.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue43721.dart.weak.modular.expect
new file mode 100644
index 0000000..4ca7943
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue43721.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue43721.dart:18:3: Error: Inferred type argument 'FutureOr<num>' doesn't conform to the bound 'FutureOr<int>' of the type variable 'T' on 'error'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   error(z); // Error.
+//   ^
+// pkg/front_end/testcases/general/issue43721.dart:10:7: Context: This is the type variable whose bound isn't conformed to.
+// error<T extends FutureOr<int>>(T t) {}
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+static method ok<T extends FutureOr<core::num*>*>(self::ok::T* t) → dynamic {}
+static method error<T extends FutureOr<core::int*>*>(self::error::T* t) → dynamic {}
+static method bar(core::bool* condition) → dynamic {
+  FutureOr<core::int*>* x = null;
+  core::num* n = 1;
+  FutureOr<core::num*>* z = condition ?{FutureOr<core::num*>*} x : n;
+  self::ok<FutureOr<core::num*>*>(z);
+  self::error<FutureOr<core::num*>*>(z);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue43975.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue43975.dart.weak.modular.expect
new file mode 100644
index 0000000..a1da936
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue43975.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue43975.dart:5:9: Error: The typedef 'F' has a reference to itself.
+// typedef F = void Function<X extends F>() Function();
+//         ^
+//
+import self as self;
+
+typedef F = invalid-type;
+static method main() → void {}
diff --git a/pkg/front_end/testcases/general/issue44007.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue44007.dart.weak.modular.expect
new file mode 100644
index 0000000..efd3a92
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue44007.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue44007.dart:16:35: Error: Expected ',' before this.
+//   print(DateTime.parse(2019-01-17 00:00:00.000));
+//                                   ^^
+//
+// pkg/front_end/testcases/general/issue44007.dart:16:35: Error: Expected an identifier, but got '00'.
+// Try inserting an identifier before '00'.
+//   print(DateTime.parse(2019-01-17 00:00:00.000));
+//                                   ^^
+//
+// pkg/front_end/testcases/general/issue44007.dart:16:40: Error: Expected ')' before this.
+//   print(DateTime.parse(2019-01-17 00:00:00.000));
+//                                        ^
+//
+// pkg/front_end/testcases/general/issue44007.dart:16:18: Error: Expected an identifier, but got 'parse'.
+// Try inserting an identifier before 'parse'.
+//   print(DateTime.parse(2019-01-17 00:00:00.000));
+//                  ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  core::List<core::DateTime> list = <core::DateTime>[new core::DateTime::now().{core::DateTime::add}(new core::Duration::•(days: 3)){(core::Duration) → core::DateTime}, new core::DateTime::now().{core::DateTime::add}(new core::Duration::•(days: 2)){(core::Duration) → core::DateTime}, new core::DateTime::now(), new core::DateTime::now().{core::DateTime::subtract}(new core::Duration::•(days: 1)){(core::Duration) → core::DateTime}];
+  list.{core::List::sort}((core::DateTime a, core::DateTime b) → core::int => a.{core::DateTime::compareTo}(b){(core::DateTime) → core::int}){([(core::DateTime, core::DateTime) →? core::int]) → void};
+  core::print(list);
+  core::print(invalid-expression "pkg/front_end/testcases/general/issue44007.dart:16:18: Error: Expected an identifier, but got 'parse'.
+Try inserting an identifier before 'parse'.
+  print(DateTime.parse(2019-01-17 00:00:00.000));
+                 ^^^^^");
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue44347.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue44347.dart.weak.modular.expect
new file mode 100644
index 0000000..0fce86b
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue44347.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue44347.dart:8:6: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   Set<int>.();
+//      ^
+//
+// pkg/front_end/testcases/general/issue44347.dart:8:13: Error: Expected an identifier, but got ')'.
+// Try inserting an identifier before ')'.
+//   Set<int>.();
+//             ^
+//
+// pkg/front_end/testcases/general/issue44347.dart:8:12: Error: Expected an identifier, but got '('.
+// Try inserting an identifier before '('.
+//   Set<int>.();
+//            ^
+//
+import self as self;
+
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/issue44347.dart:8:12: Error: Expected an identifier, but got '('.
+Try inserting an identifier before '('.
+  Set<int>.();
+           ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue44476.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue44476.dart.weak.modular.expect
new file mode 100644
index 0000000..645587c
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue44476.dart.weak.modular.expect
@@ -0,0 +1,88 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue44476.dart:7:12: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+// foo(A<num> x) {
+//            ^
+// pkg/front_end/testcases/general/issue44476.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue44476.dart:9:19: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+//     barbar(A<num> yy) => null;
+//                   ^
+// pkg/front_end/testcases/general/issue44476.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue44476.dart:8:14: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+//   bar(A<num> y) {
+//              ^
+// pkg/front_end/testcases/general/issue44476.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue44476.dart:12:26: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+//     var bazbaz = (A<num> zz) => null;
+//                          ^
+// pkg/front_end/testcases/general/issue44476.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue44476.dart:12:9: Error: Inferred type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'A'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     var bazbaz = (A<num> zz) => null;
+//         ^
+// pkg/front_end/testcases/general/issue44476.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue44476.dart:11:21: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+//   var baz = (A<num> z) {
+//                     ^
+// pkg/front_end/testcases/general/issue44476.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue44476.dart:11:7: Error: Inferred type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'A'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   var baz = (A<num> z) {
+//       ^
+// pkg/front_end/testcases/general/issue44476.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends int> {}
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::int*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo(self::A<core::num*>* x) → dynamic {
+  function bar(self::A<core::num*>* y) → Null {
+    function barbar(self::A<core::num*>* yy) → Null
+      return null;
+  }
+  (self::A<core::num*>*) →* Null baz = (self::A<core::num*>* z) → Null {
+    (self::A<core::num*>*) →* Null bazbaz = (self::A<core::num*>* zz) → Null => null;
+  };
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue44654.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue44654.dart.weak.modular.expect
new file mode 100644
index 0000000..0832149
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue44654.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method test2() → void {
+  core::String* string = null;
+  if(let final core::String* #t1 = string in #t1 == null ?{core::bool*} null : #t1.{core::String::isNotEmpty}{core::bool*})
+    ;
+}
+static method main() → void {
+  try {
+    self::test2();
+  }
+  on dynamic catch(final dynamic e, final core::StackTrace* s) {
+    self::checkFirstLineHasPosition(s);
+  }
+}
+static method checkFirstLineHasPosition(core::StackTrace* stackTrace) → void {
+  core::String* firstLine = "${stackTrace}".{core::String::split}("
+"){(core::Pattern*) →* core::List<core::String*>*}.{core::Iterable::firstWhere}((core::String* line) → core::bool* => line.{core::String::startsWith}("#0"){(core::Pattern*, [core::int*]) →* core::bool*}){((core::String*) →* core::bool*, {orElse: () →* core::String*}) →* core::String*};
+  core::int* lastParen = firstLine.{core::String::lastIndexOf}(")"){(core::Pattern*, [core::int*]) →* core::int*};
+  if(!(lastParen =={core::num::==}{(core::Object*) →* core::bool*} 1.{core::int::unary-}(){() →* core::int*})) {
+    core::int* secondColon = firstLine.{core::String::lastIndexOf}(":", lastParen.{core::num::-}(1){(core::num*) →* core::int*}){(core::Pattern*, [core::int*]) →* core::int*};
+    if(!(secondColon =={core::num::==}{(core::Object*) →* core::bool*} 1.{core::int::unary-}(){() →* core::int*})) {
+      core::int* firstColon = firstLine.{core::String::lastIndexOf}(":", secondColon.{core::num::-}(1){(core::num*) →* core::int*}){(core::Pattern*, [core::int*]) →* core::int*};
+      core::String* lineText = firstLine.{core::String::substring}(firstColon.{core::num::+}(1){(core::num*) →* core::int*}, secondColon){(core::int*, [core::int*]) →* core::String*};
+      core::String* posText = firstLine.{core::String::substring}(secondColon.{core::num::+}(1){(core::num*) →* core::int*}, lastParen){(core::int*, [core::int*]) →* core::String*};
+      core::int* line = core::int::tryParse(lineText);
+      core::int* pos = core::int::tryParse(posText);
+      if(!(line == null) && !(pos == null)) {
+        core::print("Found position ${line}:${pos}");
+        return;
+      }
+    }
+  }
+  throw "No position found in \"${firstLine}\"";
+}
diff --git a/pkg/front_end/testcases/general/issue44733.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue44733.dart.weak.modular.expect
new file mode 100644
index 0000000..0b3bd97
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue44733.dart.weak.modular.expect
@@ -0,0 +1,79 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue44733.dart:22:3: Error: Type 'F' not found.
+//   F get y => super.y as F;
+//   ^
+//
+// pkg/front_end/testcases/general/issue44733.dart:5:16: Error: 'A' doesn't implement 'D' so it can't be used with 'C'.
+//  - 'A' is from 'pkg/front_end/testcases/general/issue44733.dart'.
+//  - 'D' is from 'pkg/front_end/testcases/general/issue44733.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/general/issue44733.dart'.
+// abstract class B extends A with C {}
+//                ^
+//
+// pkg/front_end/testcases/general/issue44733.dart:9:12: Error: Expected identifier, but got 'super'.
+// B get x => super.x;
+//            ^^^^^
+//
+// pkg/front_end/testcases/general/issue44733.dart:18:9: Error: A non-null value must be returned since the return type 'E' doesn't allow null.
+//  - 'E' is from 'pkg/front_end/testcases/general/issue44733.dart'.
+//   E get y {}
+//         ^
+//
+// pkg/front_end/testcases/general/issue44733.dart:22:25: Error: 'F' isn't a type.
+//   F get y => super.y as F;
+//                         ^
+//
+// pkg/front_end/testcases/general/issue44733.dart:22:20: Error: Superclass has no getter named 'y'.
+//   F get y => super.y as F;
+//                    ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class _B&A&C = self::A with self::C /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B&A&C
+    : super self::A::•()
+    ;
+}
+abstract class B extends self::_B&A&C {
+  synthetic constructor •() → self::B
+    : super self::_B&A&C::•()
+    ;
+}
+abstract class C extends self::D /*isMixinDeclaration*/  {
+}
+abstract class E extends core::Object {
+  synthetic constructor •() → self::E
+    : super core::Object::•()
+    ;
+}
+abstract class D extends core::Object {
+  synthetic constructor •() → self::D
+    : super core::Object::•()
+    ;
+  get y() → self::E {
+    return invalid-expression "pkg/front_end/testcases/general/issue44733.dart:18:9: Error: A non-null value must be returned since the return type 'E' doesn't allow null.
+ - 'E' is from 'pkg/front_end/testcases/general/issue44733.dart'.
+  E get y {}
+        ^" in null;
+  }
+}
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  get y() → invalid-type
+    return super.y as{ForNonNullableByDefault} invalid-type;
+}
+static get x() → self::B
+  return invalid-expression "pkg/front_end/testcases/general/issue44733.dart:9:12: Error: Expected identifier, but got 'super'.
+B get x => super.x;
+           ^^^^^"{<invalid>}.x;
+static method f() → void {
+  switch(self::x.{self::A::y}{invalid-type}{<invalid>}.z) {
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue45003/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue45003/main.dart.weak.modular.expect
new file mode 100644
index 0000000..d657617
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue45003/main.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "foo_lib.dart" as foo;
+
+import "org-dartlang-testcase:///foo_lib.dart";
+
+static const field core::Set<foo::Foo> foo = #C2;
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as foo;
+import "dart:core" as core;
+import "bar_lib.dart" as bar;
+additionalExports = (bar::Bar)
+
+import "org-dartlang-testcase:///bar_lib.dart";
+export "org-dartlang-testcase:///bar_lib.dart";
+
+abstract class Foo extends core::Object /*hasConstConstructor*/  {
+  static final field dynamic _redirecting# = <dynamic>[#C3]/*isLegacy*/;
+  const constructor •() → foo::Foo
+    : super core::Object::•()
+    ;
+  static factory bar() → foo::Foo
+    return new bar::Bar::•<dynamic>();
+}
+
+library /*isNonNullableByDefault*/;
+import self as bar;
+import "dart:core" as core;
+import "foo_lib.dart" as foo;
+
+import "org-dartlang-testcase:///foo_lib.dart";
+
+class Bar<T extends core::Object? = dynamic> extends foo::Foo /*hasConstConstructor*/  {
+  const constructor •() → bar::Bar<bar::Bar::T%>
+    : super foo::Foo::•()
+    ;
+}
+
+constants  {
+  #C1 = bar::Bar<dynamic> {}
+  #C2 = <foo::Foo*>{#C1}
+  #C3 = constructor-tearoff foo::Foo::bar
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///main.dart:
+- Bar. (from org-dartlang-testcase:///bar_lib.dart:8:9)
+- Foo. (from org-dartlang-testcase:///foo_lib.dart:10:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/issue45003_2.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue45003_2.dart.weak.modular.expect
new file mode 100644
index 0000000..9e86d1c
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue45003_2.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object /*hasConstConstructor*/  {
+  const constructor •({dynamic x = #C1}) → self::C
+    : super core::Object::•()
+    ;
+}
+class B<X extends core::Object? = dynamic> extends self::A /*hasConstConstructor*/  {
+  const constructor •() → self::B<self::B::X%>
+    : super self::A::•()
+    ;
+}
+abstract class A extends core::Object /*hasConstConstructor*/  {
+  static final field dynamic _redirecting# = <dynamic>[#C2]/*isLegacy*/;
+  const constructor •() → self::A
+    : super core::Object::•()
+    ;
+  static factory foo() → self::A
+    return new self::B::•<dynamic>();
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::B<dynamic> {}
+  #C2 = constructor-tearoff self::A::foo
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue45003_2.dart:
+- B. (from org-dartlang-testcase:///issue45003_2.dart:10:9)
+- A. (from org-dartlang-testcase:///issue45003_2.dart:14:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/issue45101/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue45101/main.dart.weak.modular.expect
new file mode 100644
index 0000000..d517647
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue45101/main.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library;
+import self as self;
+
+import "dart:test";
+
+static method main() → dynamic {}
+
+library;
+import self as self2;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+import "dart:_internal";
+
+class _ArraySize<T extends core::Object* = dynamic> extends core::Object implements self2::Array<self2::_ArraySize::T*> /*hasConstConstructor*/  { // from org-dartlang-testcase:///patch_lib.dart
+  final field core::int* foo;
+  const constructor •(core::int* foo) → self2::_ArraySize<self2::_ArraySize::T*>*
+    : self2::_ArraySize::foo = foo, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+@#C1
+@#C4
+class Array<T extends core::Object* = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C5];
+  @#C1
+  static factory /* from org-dartlang-testcase:///patch_lib.dart */ •<T extends core::Object* = dynamic>(core::int* foo) → self2::Array<self2::Array::•::T*>*
+    return new self2::_ArraySize::•<self2::Array::•::T*>(foo);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+constants  {
+  #C1 = _in::_Patch {}
+  #C2 = "vm:entry-point"
+  #C3 = null
+  #C4 = core::pragma {name:#C2, options:#C3}
+  #C5 = constructor-tearoff self2::Array::•
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///origin_lib.dart:
+- pragma._ (from org-dartlang-sdk:///sdk/lib/core/annotations.dart:188:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/issue45204.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue45204.dart.weak.modular.expect
new file mode 100644
index 0000000..29d551e
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue45204.dart.weak.modular.expect
@@ -0,0 +1,213 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue45204.dart:29:8: Error: Too few positional arguments: 1 required, 0 given.
+//   S(3).test();
+//        ^
+// pkg/front_end/testcases/general/issue45204.dart:6:8: Context: Found this candidate, but the arguments don't match.
+//   void test(int x) {}
+//        ^^^^^^
+//
+// pkg/front_end/testcases/general/issue45204.dart:30:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//   S(4).test(5, 6);
+//        ^
+// pkg/front_end/testcases/general/issue45204.dart:6:8: Context: Found this candidate, but the arguments don't match.
+//   void test(int x) {}
+//        ^^^^^^
+//
+// pkg/front_end/testcases/general/issue45204.dart:31:8: Error: Expected 0 type arguments.
+//   S(5).test<int>(6);
+//        ^
+// pkg/front_end/testcases/general/issue45204.dart:6:8: Context: Found this candidate, but the arguments don't match.
+//   void test(int x) {}
+//        ^^^^^^
+//
+// pkg/front_end/testcases/general/issue45204.dart:33:9: Error: Too few positional arguments: 1 required, 0 given.
+//   S2(3).test2();
+//         ^
+// pkg/front_end/testcases/general/issue45204.dart:10:8: Context: Found this candidate, but the arguments don't match.
+//   void test2(int x) {}
+//        ^^^^^^^^
+//
+// pkg/front_end/testcases/general/issue45204.dart:34:9: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//   S2(4).test2(5, 6);
+//         ^
+// pkg/front_end/testcases/general/issue45204.dart:10:8: Context: Found this candidate, but the arguments don't match.
+//   void test2(int x) {}
+//        ^^^^^^^^
+//
+// pkg/front_end/testcases/general/issue45204.dart:35:9: Error: Expected 1 type arguments.
+//   S2(5).test2<int>(6);
+//         ^
+// pkg/front_end/testcases/general/issue45204.dart:10:8: Context: Found this candidate, but the arguments don't match.
+//   void test2(int x) {}
+//        ^^^^^^^^
+//
+// pkg/front_end/testcases/general/issue45204.dart:37:9: Error: Too few positional arguments: 1 required, 0 given.
+//   S2(3).test3();
+//         ^
+// pkg/front_end/testcases/general/issue45204.dart:11:8: Context: Found this candidate, but the arguments don't match.
+//   void test3<Y>(Y y) {}
+//        ^^^^^^^^
+//
+// pkg/front_end/testcases/general/issue45204.dart:38:9: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//   S2(4).test3(5, 6);
+//         ^
+// pkg/front_end/testcases/general/issue45204.dart:11:8: Context: Found this candidate, but the arguments don't match.
+//   void test3<Y>(Y y) {}
+//        ^^^^^^^^
+//
+// pkg/front_end/testcases/general/issue45204.dart:40:9: Error: Expected 2 type arguments.
+//   S2(6).test3<int, int>(7);
+//         ^
+// pkg/front_end/testcases/general/issue45204.dart:11:8: Context: Found this candidate, but the arguments don't match.
+//   void test3<Y>(Y y) {}
+//        ^^^^^^^^
+//
+// pkg/front_end/testcases/general/issue45204.dart:41:9: Error: Expected 2 type arguments.
+//   S2(7).test3<int, int, int>(8);
+//         ^
+// pkg/front_end/testcases/general/issue45204.dart:11:8: Context: Found this candidate, but the arguments don't match.
+//   void test3<Y>(Y y) {}
+//        ^^^^^^^^
+//
+// pkg/front_end/testcases/general/issue45204.dart:15:9: Error: Too few positional arguments: 1 required, 0 given.
+//   3.test();
+//         ^
+//
+// pkg/front_end/testcases/general/issue45204.dart:16:9: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//   4.test(5, 6);
+//         ^
+//
+// pkg/front_end/testcases/general/issue45204.dart:17:5: Error: Expected 0 type arguments.
+//   5.test<int>(6);
+//     ^
+//
+// pkg/front_end/testcases/general/issue45204.dart:19:10: Error: Too few positional arguments: 1 required, 0 given.
+//   3.test2();
+//          ^
+//
+// pkg/front_end/testcases/general/issue45204.dart:20:10: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//   4.test2(5, 6);
+//          ^
+//
+// pkg/front_end/testcases/general/issue45204.dart:21:5: Error: Expected 0 type arguments.
+//   5.test2<int>(6);
+//     ^
+//
+// pkg/front_end/testcases/general/issue45204.dart:23:10: Error: Too few positional arguments: 1 required, 0 given.
+//   3.test3();
+//          ^
+//
+// pkg/front_end/testcases/general/issue45204.dart:24:10: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//   4.test3(5, 6);
+//          ^
+//
+// pkg/front_end/testcases/general/issue45204.dart:26:5: Error: Expected 1 type arguments.
+//   6.test3<int, int>(7);
+//     ^
+//
+// pkg/front_end/testcases/general/issue45204.dart:27:5: Error: Expected 1 type arguments.
+//   7.test3<int, int, int>(8);
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+extension S on core::int {
+  method test = self::S|test;
+  tearoff test = self::S|get#test;
+}
+extension S2<X extends core::Object? = dynamic> on core::int {
+  method test2 = self::S2|test2;
+  tearoff test2 = self::S2|get#test2;
+  method test3 = self::S2|test3;
+  tearoff test3 = self::S2|get#test3;
+}
+static method S|test(lowered final core::int #this, core::int x) → void {}
+static method S|get#test(lowered final core::int #this) → (core::int) → void
+  return (core::int x) → void => self::S|test(#this, x);
+static method S2|test2<X extends core::Object? = dynamic>(lowered final core::int #this, core::int x) → void {}
+static method S2|get#test2<X extends core::Object? = dynamic>(lowered final core::int #this) → (core::int) → void
+  return (core::int x) → void => self::S2|test2<self::S2|get#test2::X%>(#this, x);
+static method S2|test3<X extends core::Object? = dynamic, Y extends core::Object? = dynamic>(lowered final core::int #this, self::S2|test3::Y% y) → void {}
+static method S2|get#test3<X extends core::Object? = dynamic>(lowered final core::int #this) → <Y extends core::Object? = dynamic>(Y%) → void
+  return <Y extends core::Object? = dynamic>(Y% y) → void => self::S2|test3<self::S2|get#test3::X%, Y%>(#this, y);
+static method foo() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:15:9: Error: Too few positional arguments: 1 required, 0 given.
+  3.test();
+        ^" in self::S|test(3);
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:16:9: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+  4.test(5, 6);
+        ^" in self::S|test(4, 5, 6);
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:17:5: Error: Expected 0 type arguments.
+  5.test<int>(6);
+    ^" in self::S|test<core::int>(5, 6);
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:19:10: Error: Too few positional arguments: 1 required, 0 given.
+  3.test2();
+         ^" in self::S2|test2<dynamic>(3);
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:20:10: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+  4.test2(5, 6);
+         ^" in self::S2|test2<dynamic>(4, 5, 6);
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:21:5: Error: Expected 0 type arguments.
+  5.test2<int>(6);
+    ^" in self::S2|test2<dynamic, core::int>(5, 6);
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:23:10: Error: Too few positional arguments: 1 required, 0 given.
+  3.test3();
+         ^" in self::S2|test3<dynamic, dynamic>(3);
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:24:10: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+  4.test3(5, 6);
+         ^" in self::S2|test3<dynamic, core::int>(4, 5, 6);
+  self::S2|test3<dynamic, core::int>(5, 6);
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:26:5: Error: Expected 1 type arguments.
+  6.test3<int, int>(7);
+    ^" in self::S2|test3<dynamic, core::int, core::int>(6, 7);
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:27:5: Error: Expected 1 type arguments.
+  7.test3<int, int, int>(8);
+    ^" in self::S2|test3<dynamic, core::int, core::int, core::int>(7, 8);
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:29:8: Error: Too few positional arguments: 1 required, 0 given.
+  S(3).test();
+       ^";
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:30:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+  S(4).test(5, 6);
+       ^";
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:31:8: Error: Expected 0 type arguments.
+  S(5).test<int>(6);
+       ^";
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:33:9: Error: Too few positional arguments: 1 required, 0 given.
+  S2(3).test2();
+        ^";
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:34:9: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+  S2(4).test2(5, 6);
+        ^";
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:35:9: Error: Expected 1 type arguments.
+  S2(5).test2<int>(6);
+        ^";
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:37:9: Error: Too few positional arguments: 1 required, 0 given.
+  S2(3).test3();
+        ^";
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:38:9: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+  S2(4).test3(5, 6);
+        ^";
+  self::S2|test3<dynamic, core::int>(5, 6);
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:40:9: Error: Expected 2 type arguments.
+  S2(6).test3<int, int>(7);
+        ^";
+  invalid-expression "pkg/front_end/testcases/general/issue45204.dart:41:9: Error: Expected 2 type arguments.
+  S2(7).test3<int, int, int>(8);
+        ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue45330.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue45330.dart.weak.modular.expect
new file mode 100644
index 0000000..56fe32f
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue45330.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue45330.dart:12:31: Error: Type 'T' is a bound of itself via 'T'.
+// Try breaking the cycle by removing at least on of the 'extends' clauses in the cycle.
+//   genericMethod<void Function<T extends T>()>();
+//                               ^
+//
+// pkg/front_end/testcases/general/issue45330.dart:12:3: Error: A generic function type can't be used as a type argument.
+// Try using a non-generic function type.
+//   genericMethod<void Function<T extends T>()>();
+//   ^
+//
+// pkg/front_end/testcases/general/issue45330_lib.dart:37:31: Error: Type 'T' is a bound of itself via 'T'.
+// Try breaking the cycle by removing at least on of the 'extends' clauses in the cycle.
+//   genericMethod<void Function<T extends T>()>();
+//                               ^
+//
+// pkg/front_end/testcases/general/issue45330_lib.dart:37:3: Error: A generic function type can't be used as a type argument.
+// Try using a non-generic function type.
+//   genericMethod<void Function<T extends T>()>();
+//   ^
+//
+import self as self;
+import "dart:core" as core;
+
+part issue45330_lib.dart;
+static method genericMethod<T extends core::Object? = dynamic>() → void {}
+static method testInMain() → dynamic {
+  self::genericMethod<<T extends invalid-type>() → void>();
+}
+static method main() → dynamic {}
+static method /* from org-dartlang-testcase:///issue45330_lib.dart */ testInPart() → dynamic {
+  self::genericMethod<<T extends invalid-type>() → void>();
+}
diff --git a/pkg/front_end/testcases/general/issue45490.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue45490.dart.weak.modular.expect
new file mode 100644
index 0000000..4ebc700
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue45490.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue45490.dart:7:29: Error: Expected '>' after this.
+// class test<X extends A> = A<X extends A<X>>;
+//                             ^
+//
+// pkg/front_end/testcases/general/issue45490.dart:7:44: Error: Expected 'with' before this.
+// class test<X extends A> = A<X extends A<X>>;
+//                                            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue45598.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue45598.dart.weak.modular.expect
new file mode 100644
index 0000000..4463884
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue45598.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method foo(<X extends Z* = dynamic, Y extends core::Object* = dynamic, Z extends core::Object* = dynamic>({m: core::Map<Y*, Z*>*}) →* dynamic bar, core::Map<core::String*, core::String*>* m) → dynamic {
+  bar<core::String*, core::String*, core::String*>(m: m){({m: core::Map<core::String*, core::String*>*}) →* dynamic};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue45598_2.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue45598_2.dart.weak.modular.expect
new file mode 100644
index 0000000..eff30fa
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue45598_2.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method foo(core::Map<core::String*, core::String*>* m) → dynamic {
+  function bar<X extends Z* = dynamic, Y extends core::Object* = dynamic, Z extends core::Object* = dynamic>({core::Map<Y*, Z*>* m = #C1}) → void {}
+  bar<core::String*, core::String*, core::String*>(m: m){({m: core::Map<core::String*, core::String*>*}) →* void};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/issue45660.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue45660.dart.weak.modular.expect
new file mode 100644
index 0000000..5111de9
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue45660.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue45660.dart:11:22: Error: Inferred type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'call'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   extendsNumReturnArg/*<String>*/("");
+//                      ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field <T extends core::num* = dynamic>(T*) →* T* extendsNumReturnArg = <S extends core::num*>(S* s) → S* => s;
+static method functionInvocations() → dynamic {
+  self::extendsNumReturnArg<Null>(null){(Null) →* Null};
+  self::extendsNumReturnArg<core::String*>(""){(core::String*) →* core::String*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue45700.crash_dart.weak.modular.expect b/pkg/front_end/testcases/general/issue45700.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..a03c56f
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue45700.crash_dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue45700.crash_dart:5:7: Error: Can't use a function type as supertype.
+// mixin M on Function() {}
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class M extends core::Object /*isMixinDeclaration*/  {
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/general/issue45834.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue45834.dart.weak.modular.expect
new file mode 100644
index 0000000..62ca870
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue45834.dart.weak.modular.expect
@@ -0,0 +1,211 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue45834.dart:7:10: Error: Type variables can't have generic function types in their bounds.
+// class A1<X extends Function<T>()> {
+//          ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:8:15: Error: Type variables can't have generic function types in their bounds.
+//   A1(Function<X extends Function<T>()>() f);
+//               ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:9:17: Error: Type variables can't have generic function types in their bounds.
+//   bar1(Function<X extends Function<T>()>() f) {}
+//                 ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:10:12: Error: Type variables can't have generic function types in their bounds.
+//   Function<X extends Function<T>()>() bar2() => throw 42;
+//            ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:11:12: Error: Type variables can't have generic function types in their bounds.
+//   Function<X extends Function<T>()>() get baz1 => throw 42;
+//            ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:13:12: Error: Type variables can't have generic function types in their bounds.
+//   Function<X extends Function<T>()>() quux1 = throw 42;
+//            ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:14:19: Error: Type variables can't have generic function types in their bounds.
+//   static Function<X extends Function<T>()>() quux2 = throw 42;
+//                   ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:12:26: Error: Type variables can't have generic function types in their bounds.
+//   void set qux1(Function<X extends Function<T>()>() value) {}
+//                          ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:17:10: Error: Type variables can't have generic function types in their bounds.
+// class A2<X extends void Function<Y extends Function<T>()>()> {}
+//          ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:17:34: Error: Type variables can't have generic function types in their bounds.
+// class A2<X extends void Function<Y extends Function<T>()>()> {}
+//                                  ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:22:15: Error: Type variables can't have generic function types in their bounds.
+// foo1(Function<X extends Function<T>()>() f) {}
+//               ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:24:10: Error: Type variables can't have generic function types in their bounds.
+// Function<X extends Function<T>()>() foo3() => throw 42;
+//          ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:26:10: Error: Type variables can't have generic function types in their bounds.
+// Function<X extends Function<T>()>() get corge1 => throw 42;
+//          ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:28:10: Error: Type variables can't have generic function types in their bounds.
+// Function<X extends Function<T>()>() quuz1 = throw 42;
+//          ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:30:28: Error: Type variables can't have generic function types in their bounds.
+// typedef F1 = void Function<X extends void Function<T>()>();
+//                            ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:32:12: Error: Type variables can't have generic function types in their bounds.
+// typedef F3<X extends Function<T>()> = Function();
+//            ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:33:12: Error: Type variables can't have generic function types in their bounds.
+// typedef F4<X extends Function<Y extends Function<T>()>()> = Function();
+//            ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:33:31: Error: Type variables can't have generic function types in their bounds.
+// typedef F4<X extends Function<Y extends Function<T>()>()> = Function();
+//                               ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:39:14: Error: Type variables can't have generic function types in their bounds.
+// extension E1<X extends Function<T>()> on B1 {
+//              ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:40:17: Error: Type variables can't have generic function types in their bounds.
+//   bar3(Function<X extends Function<T>()>() f) {}
+//                 ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:41:12: Error: Type variables can't have generic function types in their bounds.
+//   Function<X extends Function<T>()>() bar4() => throw 42;
+//            ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:42:12: Error: Type variables can't have generic function types in their bounds.
+//   Function<X extends Function<T>()>() get baz2 => throw 42;
+//            ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:44:19: Error: Type variables can't have generic function types in their bounds.
+//   static Function<X extends Function<T>()>() quux3 = throw 42;
+//                   ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:43:26: Error: Type variables can't have generic function types in their bounds.
+//   void set qux2(Function<X extends Function<T>()>() value) {}
+//                          ^
+//
+// pkg/front_end/testcases/general/issue45834.dart:27:27: Error: Type variables can't have generic function types in their bounds.
+// void set grault1(Function<X extends Function<T>()>() value) {}
+//                           ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F1 = <X extends <T extends core::Object* = dynamic>() →* void = dynamic>() →* void;
+typedef F2 = <X extends (<T extends core::Object* = dynamic>() →* void) →* dynamic = dynamic>() →* void;
+typedef F3<unrelated X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic> = () →* dynamic;
+typedef F4<unrelated X extends <Y extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic = dynamic> = () →* dynamic;
+typedef F5<unrelated X extends (<Y extends (<T extends core::Object* = dynamic>() →* dynamic) →* dynamic = dynamic>() →* dynamic) →* dynamic> = () →* dynamic;
+class A1<X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic> extends core::Object {
+  field <X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic quux1 = throw 42;
+  static field <X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic quux2 = throw 42;
+  constructor •(<X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic f) → self::A1<self::A1::X*>*
+    : super core::Object::•()
+    ;
+  method bar1(<X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic f) → dynamic {}
+  method bar2() → <X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic
+    return throw 42;
+  get baz1() → <X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic
+    return throw 42;
+  set qux1(<X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A2<X extends <Y extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* void = dynamic> extends core::Object {
+  synthetic constructor •() → self::A2<self::A2::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A3<X extends (<Y extends (<T extends core::Object* = dynamic>() →* dynamic) →* dynamic = dynamic>() →* void) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::A3<self::A3::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B1 extends core::Object {
+  synthetic constructor •() → self::B1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension E1<X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic> on self::B1* {
+  method bar3 = self::E1|bar3;
+  tearoff bar3 = self::E1|get#bar3;
+  method bar4 = self::E1|bar4;
+  tearoff bar4 = self::E1|get#bar4;
+  get baz2 = self::E1|get#baz2;
+  static field quux3 = self::E1|quux3;
+  set qux2 = self::E1|set#qux2;
+}
+static field <X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic quuz1 = throw 42;
+static field <X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic E1|quux3 = throw 42;
+static method foo1(<X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic f) → dynamic {}
+static method foo2(<X extends (<T extends core::Object* = dynamic>() →* dynamic) →* dynamic = dynamic>() →* dynamic f) → dynamic {}
+static method foo3() → <X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic
+  return throw 42;
+static method foo4() → <X extends (<T extends core::Object* = dynamic>() →* dynamic) →* dynamic = dynamic>() →* dynamic
+  return throw 42;
+static get corge1() → <X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic
+  return throw 42;
+static set grault1(<X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic value) → void {}
+static method E1|bar3<X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>(lowered final self::B1* #this, <X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic f) → dynamic {}
+static method E1|get#bar3<X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>(lowered final self::B1* #this) → (<X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic) →* dynamic
+  return (<X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic f) → dynamic => self::E1|bar3<self::E1|get#bar3::X*>(#this, f);
+static method E1|bar4<X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>(lowered final self::B1* #this) → <X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic
+  return throw 42;
+static method E1|get#bar4<X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>(lowered final self::B1* #this) → () →* <X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic
+  return () → <X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic => self::E1|bar4<self::E1|get#bar4::X*>(#this);
+static method E1|get#baz2<X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>(lowered final self::B1* #this) → <X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic
+  return throw 42;
+static method E1|set#qux2<X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>(lowered final self::B1* #this, <X extends <T extends core::Object* = dynamic>() →* dynamic = dynamic>() →* dynamic value) → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue46334.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue46334.dart.weak.modular.expect
new file mode 100644
index 0000000..e0ea5d7
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue46334.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue46334.dart:6:11: Error: Cyclic definition of factory 'C'.
+//   factory C() = C;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  static factory •() → self::C
+    return invalid-expression "pkg/front_end/testcases/general/issue46334.dart:6:11: Error: Cyclic definition of factory 'C'.
+  factory C() = C;
+          ^";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::C::•
+}
diff --git a/pkg/front_end/testcases/general/issue46389.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue46389.dart.weak.modular.expect
new file mode 100644
index 0000000..55be1b7
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue46389.dart.weak.modular.expect
@@ -0,0 +1,73 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int boz = 0;
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method foo(core::int n) → core::num {
+    core::print(n.{core::Object::runtimeType}{core::Type});
+    return 1.1;
+  }
+  method bar({required core::int x = #C1}) → core::num {
+    core::print(x.{core::Object::runtimeType}{core::Type});
+    return 1.1;
+  }
+  set baz(core::int x) → void {
+    core::print(x.{core::Object::runtimeType}{core::Type});
+  }
+}
+abstract class B<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::X%>
+    : super core::Object::•()
+    ;
+  abstract method foo(covariant-by-class self::B::X% x) → self::B::X%;
+  abstract method bar({required covariant-by-class self::B::X% x = #C1}) → self::B::X%;
+  abstract set baz(covariant-by-class self::B::X% x) → void;
+  abstract set boz(covariant-by-class self::B::X% x) → void;
+}
+abstract class _C&A&B = self::A with self::B<core::num> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_C&A&B
+    : super self::A::•()
+    ;
+  forwarding-stub set boz(covariant-by-class core::num x) → void
+    return super.{self::A::boz} = x as core::int;
+  forwarding-stub method foo(covariant-by-class core::num x) → core::num
+    return super.{self::A::foo}(x as core::int);
+  forwarding-stub method bar({required covariant-by-class core::num x = #C1}) → core::num
+    return super.{self::A::bar}(x: x as core::int);
+  forwarding-stub set baz(covariant-by-class core::num x) → void
+    return super.{self::A::baz} = x as core::int;
+}
+class C extends self::_C&A&B {
+  synthetic constructor •() → self::C
+    : super self::_C&A&B::•()
+    ;
+}
+static method main() → void {
+  self::C a = new self::C::•();
+  a.{self::_C&A&B::foo}(1){(core::num) → core::num};
+  self::throws(() → void => a.{self::_C&A&B::foo}(1.2){(core::num) → core::num});
+  a.{self::_C&A&B::bar}(x: 1){({required x: core::num}) → core::num};
+  self::throws(() → void => a.{self::_C&A&B::bar}(x: 1.2){({required x: core::num}) → core::num});
+  a.{self::_C&A&B::baz} = 1;
+  self::throws(() → void => a.{self::_C&A&B::baz} = 1.2);
+  a.{self::_C&A&B::boz} = 1;
+  self::throws(() → void => a.{self::_C&A&B::boz} = 1.2);
+}
+static method throws(() → void f) → dynamic {
+  try {
+    f(){() → void};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print(e);
+    return;
+  }
+  throw "Exception expected";
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/issue46390.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue46390.dart.weak.modular.expect
new file mode 100644
index 0000000..8c31872
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue46390.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method foo(core::num n) → core::num {
+    core::print(n.{core::Object::runtimeType}{core::Type});
+    return 1.1;
+  }
+}
+abstract class B<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::X%>
+    : super core::Object::•()
+    ;
+  abstract method foo(covariant-by-class self::B::X% x) → self::B::X%;
+}
+abstract class _C&A&B = self::A with self::B<core::num> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_C&A&B
+    : super self::A::•()
+    ;
+  forwarding-stub method foo(covariant-by-class core::num x) → core::num
+    return super.{self::A::foo}(x);
+}
+class C extends self::_C&A&B {
+  synthetic constructor •() → self::C
+    : super self::_C&A&B::•()
+    ;
+}
+static method main() → void {
+  self::B<core::Object> b = new self::C::•();
+  try {
+    b.{self::B::foo}(true){(core::Object) → core::Object};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print(e);
+    return;
+  }
+  throw "Missing type error";
+}
diff --git a/pkg/front_end/testcases/general/issue46581.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue46581.dart.weak.modular.expect
new file mode 100644
index 0000000..e6c9e95
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue46581.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "issue46581_lib.dart" as iss;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue46581_lib.dart";
+
+abstract class _TestClass&MyClass&MyMixin = iss::MyClass with self::MyMixin /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor _() → self::_TestClass&MyClass&MyMixin
+    : super iss::MyClass::_()
+    ;
+  const synthetic constructor named() → self::_TestClass&MyClass&MyMixin
+    : super iss::MyClass::named()
+    ;
+}
+class TestClass extends self::_TestClass&MyClass&MyMixin {
+  constructor •() → self::TestClass
+    : super self::_TestClass&MyClass&MyMixin::named()
+    ;
+}
+abstract class MyMixin extends core::Object /*isMixinDeclaration*/  {
+}
+static method main() → void {}
+
+library /*isNonNullableByDefault*/;
+import self as iss;
+import "dart:core" as core;
+
+class MyClass extends core::Object /*hasConstConstructor*/  {
+  const constructor _() → iss::MyClass
+    : super core::Object::•()
+    ;
+  const constructor named() → iss::MyClass
+    : this iss::MyClass::_()
+    ;
+}
diff --git a/pkg/front_end/testcases/general/issue46581/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue46581/main.dart.weak.modular.expect
new file mode 100644
index 0000000..b46584b
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue46581/main.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "main_lib.dart" as mai;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+abstract class _TestClass&MyClass&MyMixin = mai::MyClass with self::MyMixin /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor _() → self::_TestClass&MyClass&MyMixin
+    : super mai::MyClass::_()
+    ;
+  const synthetic constructor named() → self::_TestClass&MyClass&MyMixin
+    : super mai::MyClass::named()
+    ;
+}
+class TestClass extends self::_TestClass&MyClass&MyMixin {
+  constructor •() → self::TestClass
+    : super self::_TestClass&MyClass&MyMixin::named()
+    ;
+}
+abstract class MyMixin extends core::Object /*isMixinDeclaration*/  {
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/general/issue46719.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue46719.dart.weak.modular.expect
new file mode 100644
index 0000000..449b259
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue46719.dart.weak.modular.expect
@@ -0,0 +1,120 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue46719.dart:27:12: Error: Couldn't find constructor 'm.applyAndPrint'.
+//   a.m<int>.applyAndPrint([2]);
+//            ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/issue46719.dart:28:15: Error: Couldn't find constructor 'm.applyAndPrint'.
+//   a.m<String>.applyAndPrint(['three']);
+//               ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/issue46719.dart:29:12: Error: Couldn't find constructor 'n.applyAndPrint'.
+//   A.n<int>.applyAndPrint([2]);
+//            ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/issue46719.dart:30:15: Error: Couldn't find constructor 'n.applyAndPrint'.
+//   A.n<String>.applyAndPrint(['three']);
+//               ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/issue46719.dart:31:15: Error: Couldn't find constructor 'm.applyAndPrint'.
+//   self.m<int>.applyAndPrint([2]);
+//               ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/issue46719.dart:32:18: Error: Couldn't find constructor 'm.applyAndPrint'.
+//   self.m<String>.applyAndPrint(['three']);
+//                  ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/issue46719.dart:33:11: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   self.A.n<int>.applyAndPrint([2]);
+//           ^
+//
+// pkg/front_end/testcases/general/issue46719.dart:34:11: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   self.A.n<String>.applyAndPrint(['three']);
+//           ^
+//
+// pkg/front_end/testcases/general/issue46719.dart:35:5: Error: Member not found: 'named'.
+//   A.named.toString();
+//     ^^^^^
+//
+// pkg/front_end/testcases/general/issue46719.dart:36:4: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   A<int>.named.toString();
+//    ^
+//
+// pkg/front_end/testcases/general/issue46719.dart:36:10: Error: Member not found: 'named'.
+//   A<int>.named.toString();
+//          ^^^^^
+//
+// pkg/front_end/testcases/general/issue46719.dart:37:5: Error: Couldn't find constructor 'named'.
+//   A.named<int>.toString();
+//     ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue46719.dart" as self;
+
+class A<T extends core::Object? = dynamic> extends core::Object {
+  constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+  constructor named() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+  method m<X extends core::Object? = dynamic>(self::A::m::X% x) → core::List<self::A::m::X%>
+    return <self::A::m::X%>[x];
+  static method n<X extends core::Object? = dynamic>(self::A::n::X% x) → core::List<self::A::n::X%>
+    return <self::A::n::X%>[x];
+}
+extension FunctionApplier on core::Function {
+  method applyAndPrint = self::FunctionApplier|applyAndPrint;
+  tearoff applyAndPrint = self::FunctionApplier|get#applyAndPrint;
+}
+static method m<X extends core::Object? = dynamic>(self::m::X% x) → core::List<self::m::X%>
+  return <self::m::X%>[x];
+static method FunctionApplier|applyAndPrint(lowered final core::Function #this, core::List<core::Object?> positionalArguments) → void
+  return core::print(core::Function::apply(#this, positionalArguments, #C1));
+static method FunctionApplier|get#applyAndPrint(lowered final core::Function #this) → (core::List<core::Object?>) → void
+  return (core::List<core::Object?> positionalArguments) → void => self::FunctionApplier|applyAndPrint(#this, positionalArguments);
+static method test() → dynamic {
+  self::A<dynamic> a = new self::A::•<dynamic>();
+  invalid-expression "pkg/front_end/testcases/general/issue46719.dart:27:12: Error: Couldn't find constructor 'm.applyAndPrint'.
+  a.m<int>.applyAndPrint([2]);
+           ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/issue46719.dart:28:15: Error: Couldn't find constructor 'm.applyAndPrint'.
+  a.m<String>.applyAndPrint(['three']);
+              ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/issue46719.dart:29:12: Error: Couldn't find constructor 'n.applyAndPrint'.
+  A.n<int>.applyAndPrint([2]);
+           ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/issue46719.dart:30:15: Error: Couldn't find constructor 'n.applyAndPrint'.
+  A.n<String>.applyAndPrint(['three']);
+              ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/issue46719.dart:31:15: Error: Couldn't find constructor 'm.applyAndPrint'.
+  self.m<int>.applyAndPrint([2]);
+              ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/issue46719.dart:32:18: Error: Couldn't find constructor 'm.applyAndPrint'.
+  self.m<String>.applyAndPrint(['three']);
+                 ^^^^^^^^^^^^^";
+  self::FunctionApplier|applyAndPrint(#C2, <core::Object?>[2]);
+  self::FunctionApplier|applyAndPrint(#C2, <core::Object?>["three"]);
+  invalid-expression "pkg/front_end/testcases/general/issue46719.dart:35:5: Error: Member not found: 'named'.
+  A.named.toString();
+    ^^^^^".{core::Object::toString}(){() → core::String};
+  invalid-expression "pkg/front_end/testcases/general/issue46719.dart:36:10: Error: Member not found: 'named'.
+  A<int>.named.toString();
+         ^^^^^".{core::Object::toString}(){() → core::String};
+  invalid-expression "pkg/front_end/testcases/general/issue46719.dart:37:5: Error: Couldn't find constructor 'named'.
+  A.named<int>.toString();
+    ^^^^^";
+}
+static method main() → void {}
+
+constants  {
+  #C1 = <core::Symbol*, dynamic>{)
+  #C2 = static-tearoff self::A::n
+}
diff --git a/pkg/front_end/testcases/general/issue46745.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue46745.dart.weak.modular.expect
new file mode 100644
index 0000000..a375575
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue46745.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue46745.dart:8:3: Error: 'A.foo' is already declared in this scope.
+//   A.foo();
+//   ^^^^^
+// pkg/front_end/testcases/general/issue46745.dart:7:11: Context: Previous declaration of 'A.foo'.
+//   factory A.foo() => A._();
+//           ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  constructor _() → self::A
+    : super core::Object::•()
+    ;
+  static factory foo() → self::A
+    return new self::A::_();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue46863.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue46863.dart.weak.modular.expect
new file mode 100644
index 0000000..20ac68c
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue46863.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue46863.dart:5:36: Error: Method not found: 'bar'.
+// final foo = [() => const [], () => bar()];
+//                                    ^^^
+//
+// pkg/front_end/testcases/general/issue46863.dart:7:41: Error: 'Bar' isn't a type.
+// final foo2 = [(dynamic x) => const [], (Bar x) => const []];
+//                                         ^^^
+//
+// pkg/front_end/testcases/general/issue46863.dart:9:52: Error: 'Bar' isn't a type.
+// final foo3 = [(List<dynamic> x) => const [], (List<Bar> x) => const []];
+//                                                    ^^^
+//
+// pkg/front_end/testcases/general/issue46863.dart:11:60: Error: 'Bar' isn't a type.
+// final foo4 = [(Function(dynamic) x) => const [], (Function(Bar) x) => const []];
+//                                                            ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static final field core::List<() → invalid-type> foo = <() → invalid-type>[() → core::List<dynamic> => #C1, () → invalid-type => invalid-expression "pkg/front_end/testcases/general/issue46863.dart:5:36: Error: Method not found: 'bar'.
+final foo = [() => const [], () => bar()];
+                                   ^^^"];
+static final field core::List<(invalid-type) → core::List<dynamic>> foo2 = <(invalid-type) → core::List<dynamic>>[(dynamic x) → core::List<dynamic> => #C1, (invalid-type x) → core::List<dynamic> => #C1];
+static final field core::List<(core::List<dynamic>) → core::List<dynamic>> foo3 = <(core::List<dynamic>) → core::List<dynamic>>[(core::List<dynamic> x) → core::List<dynamic> => #C1, (core::List<invalid-type> x) → core::List<dynamic> => #C1];
+static final field core::List<((invalid-type) → dynamic) → core::List<dynamic>> foo4 = <((invalid-type) → dynamic) → core::List<dynamic>>[((dynamic) → dynamic x) → core::List<dynamic> => #C1, ((invalid-type) → dynamic x) → core::List<dynamic> => #C1];
+static method main() → dynamic {}
+
+constants  {
+  #C1 = <dynamic>[]
+}
diff --git a/pkg/front_end/testcases/general/issue46956.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue46956.dart.weak.modular.expect
new file mode 100644
index 0000000..eb4a9a3
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue46956.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class A<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+}
+static method foo<X extends core::Object?>(self::A<self::foo::X%> x) → asy::Future<self::foo::X?>
+  return throw 42;
+static method bar(core::String? y) → dynamic {}
+static method test(self::A<core::String> a) → dynamic async {
+  final core::String? x = await(() → asy::Future<core::String?> async {
+    return self::foo<core::String>(a);
+  })(){() → asy::Future<core::String?>};
+  self::bar(x);
+}
+static method test2(self::A<core::String> a) → dynamic async {
+  return self::foo<core::String>(a);
+}
+static method test3(self::A<core::String> a) → dynamic {
+  return self::foo<core::String>(a);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue47013.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47013.dart.weak.modular.expect
new file mode 100644
index 0000000..f555ae6
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47013.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method m(core::int n) → void {}
+}
+abstract class I extends core::Object {
+  synthetic constructor •() → self::I
+    : super core::Object::•()
+    ;
+  abstract method m(covariant-by-declaration core::num n) → void;
+}
+class C extends self::A implements self::I {
+  synthetic constructor •() → self::C
+    : super self::A::•()
+    ;
+  forwarding-stub method m(covariant-by-declaration core::num n) → void
+    return super.{self::A::m}(n as core::int);
+}
+static method main() → void {
+  self::throws(() → void => (new self::C::•() as{ForNonNullableByDefault} dynamic){dynamic}.m(1.1));
+}
+static method throws(() → void f) → dynamic {
+  try {
+    f(){() → void};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print(e);
+    return;
+  }
+  throw "Exception expected";
+}
diff --git a/pkg/front_end/testcases/general/issue47013b.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47013b.dart.weak.modular.expect
new file mode 100644
index 0000000..7ab0301
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47013b.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method m(core::num n) → void {}
+}
+class B extends self::A {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+  forwarding-stub forwarding-semi-stub method /* signature-type: (core::int) → void */ m(covariant-by-declaration core::num i) → void
+    return super.{self::A::m}(i);
+}
+class C extends self::B {
+  synthetic constructor •() → self::C
+    : super self::B::•()
+    ;
+  method m(covariant-by-declaration core::int i) → void {}
+}
+static method main() → dynamic {
+  self::A a = new self::C::•();
+  self::throws(() → void => a.{self::A::m}(1.5){(core::num) → void});
+  a = new self::B::•();
+  a.{self::A::m}(1.5){(core::num) → void};
+}
+static method throws(() → void f) → dynamic {
+  try {
+    f(){() → void};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print(e);
+    return;
+  }
+  throw "Exception expected";
+}
diff --git a/pkg/front_end/testcases/general/issue47013c.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47013c.dart.weak.modular.expect
new file mode 100644
index 0000000..e4ef550
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47013c.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class D1 extends core::Object {
+  synthetic constructor •() → self::D1
+    : super core::Object::•()
+    ;
+}
+class D2 extends core::Object {
+  synthetic constructor •() → self::D2
+    : super core::Object::•()
+    ;
+}
+class D extends core::Object implements self::D1, self::D2 {
+  synthetic constructor •() → self::D
+    : super core::Object::•()
+    ;
+}
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method m(covariant-by-declaration self::D d) → void {}
+}
+abstract class B1 extends core::Object {
+  synthetic constructor •() → self::B1
+    : super core::Object::•()
+    ;
+  abstract method m(self::D1 d1) → void;
+}
+abstract class B2 extends core::Object {
+  synthetic constructor •() → self::B2
+    : super core::Object::•()
+    ;
+  abstract method m(self::D2 d2) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue47013d.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47013d.dart.weak.modular.expect
new file mode 100644
index 0000000..20bde3e
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47013d.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue47013d.dart:15:20: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+//   throws(() => b.m(1.5, 0));
+//                    ^
+//
+// pkg/front_end/testcases/general/issue47013d.dart:17:23: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+//   throws(() => a.m(1, 1.5));
+//                       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method m(core::num n, core::int i) → void {}
+}
+class B extends self::A {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+  forwarding-stub forwarding-semi-stub method /* signature-type: (core::int, core::num) → void */ m(covariant-by-declaration core::num i, covariant-by-declaration core::int n) → void
+    return super.{self::A::m}(i, n);
+}
+static method main() → dynamic {
+  self::B b = new self::B::•();
+  self::throws(() → void => b.{self::B::m}(invalid-expression "pkg/front_end/testcases/general/issue47013d.dart:15:20: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+  throws(() => b.m(1.5, 0));
+                   ^" in 1.5 as{TypeError,ForNonNullableByDefault} core::int, 0){(core::int, core::num) → void});
+  self::A a = b;
+  self::throws(() → void => a.{self::A::m}(1, invalid-expression "pkg/front_end/testcases/general/issue47013d.dart:17:23: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+  throws(() => a.m(1, 1.5));
+                      ^" in 1.5 as{TypeError,ForNonNullableByDefault} core::int){(core::num, core::int) → void});
+}
+static method throws(() → void f) → dynamic {
+  try {
+    f(){() → void};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print(e);
+    return;
+  }
+  throw "Exception expected";
+}
diff --git a/pkg/front_end/testcases/general/issue47036.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47036.dart.weak.modular.expect
new file mode 100644
index 0000000..706562c
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47036.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Default extends core::Object /*hasConstConstructor*/  {
+  final field core::Object? defaultValue;
+  const constructor •(core::Object? defaultValue) → self::Default
+    : self::Default::defaultValue = defaultValue, super core::Object::•()
+    ;
+}
+class Settings extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  static factory •({@#C3 self::Sidebar sidebar = #C4}) → self::Settings
+    return self::_SSettings::•(sidebar: sidebar);
+}
+class Sidebar extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C5]/*isLegacy*/;
+  static factory •() → self::Sidebar
+    return self::_SSidebar::•();
+}
+abstract class _SSettings extends core::Object implements self::Settings {
+  static final field dynamic _redirecting# = <dynamic>[#C6]/*isLegacy*/;
+  static factory •({self::Sidebar sidebar = #C4}) → self::_SSettings
+    return new self::_$_SSettings::•(sidebar: sidebar);
+}
+class _$_SSettings extends core::Object implements self::_SSettings /*hasConstConstructor*/  {
+  final field self::Sidebar sidebar;
+  const constructor •({self::Sidebar sidebar = #C2}) → self::_$_SSettings
+    : self::_$_SSettings::sidebar = sidebar, super core::Object::•()
+    ;
+}
+abstract class _SSidebar extends core::Object implements self::Sidebar {
+  static final field dynamic _redirecting# = <dynamic>[#C7]/*isLegacy*/;
+  static factory •() → self::_SSidebar
+    return new self::_$_SSidebar::•();
+}
+class _$_SSidebar extends core::Object implements self::_SSidebar /*hasConstConstructor*/  {
+  const constructor •() → self::_$_SSidebar
+    : super core::Object::•()
+    ;
+}
+static method main() → void {}
+
+constants  {
+  #C1 = constructor-tearoff self::Settings::•
+  #C2 = self::_$_SSidebar {}
+  #C3 = self::Default {defaultValue:#C2}
+  #C4 = null
+  #C5 = constructor-tearoff self::Sidebar::•
+  #C6 = constructor-tearoff self::_SSettings::•
+  #C7 = constructor-tearoff self::_SSidebar::•
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue47036.dart:
+- _$_SSidebar. (from org-dartlang-testcase:///issue47036.dart:36:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Default. (from org-dartlang-testcase:///issue47036.dart:6:9)
diff --git a/pkg/front_end/testcases/general/issue47057.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47057.dart.weak.modular.expect
new file mode 100644
index 0000000..abd22ad
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47057.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+static method foo<X extends core::Object?>(self::foo::X% x) → asy::Future<core::int> async {
+  if(x is{ForNonNullableByDefault} asy::Future<core::int>) {
+    return x{self::foo::X% & asy::Future<core::int> /* '%' & '!' = '!' */};
+  }
+  else {
+    throw 42;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue47072.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47072.dart.weak.modular.expect
new file mode 100644
index 0000000..54bf6d2
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47072.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class B extends self::A {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  method f(self::B b) → void {}
+}
+abstract class I extends core::Object {
+  synthetic constructor •() → self::I
+    : super core::Object::•()
+    ;
+  abstract method f(covariant-by-declaration self::A a) → void;
+}
+class D extends self::C implements self::I {
+  synthetic constructor •() → self::D
+    : super self::C::•()
+    ;
+  forwarding-stub method f(covariant-by-declaration self::A a) → void
+    return super.{self::C::f}(a as self::B);
+}
+static method main() → void {
+  self::I i = new self::D::•();
+  try {
+    i.{self::I::f}(new self::A::•()){(self::A) → void};
+  }
+  on core::Object catch(final core::Object _) {
+    return;
+  }
+  throw "Missing type error";
+}
diff --git a/pkg/front_end/testcases/general/issue47223a.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47223a.dart.weak.modular.expect
new file mode 100644
index 0000000..1640c03
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47223a.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue47223a.dart:6:4: Warning: Operand of null-aware operation '??' has type 'Never' which excludes null.
+//   (throw "some value") ?? "some other value";
+//    ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  let final Never #t1 = throw "some value" in #t1 == null ?{core::String} "some other value" : #t1;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue47223b.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47223b.dart.weak.modular.expect
new file mode 100644
index 0000000..13e925e
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47223b.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue47223b.dart:6:24: Warning: Operand of null-aware operation '??=' has type 'Never' which excludes null.
+//   (throw "some value").foo ??= "foo";
+//                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  let final Never #t1 = throw "some value" in #t1{Never}.foo == null ?{core::String} #t1{Never}.foo = "foo" : null;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue47339.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47339.dart.weak.modular.expect
new file mode 100644
index 0000000..02f1b57
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47339.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef Bar = self::Foo;
+typedef BarGeneric<X extends core::Object? = dynamic> = self::FooGeneric<X%>;
+class Foo extends core::Object /*hasConstConstructor*/  {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  const constructor named() → self::Foo
+    : super core::Object::•()
+    ;
+  static factory namedFactory() → self::Foo
+    return new self::Foo::named();
+}
+class FooGeneric<X extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  static final field dynamic _redirecting# = <dynamic>[#C2]/*isLegacy*/;
+  const constructor named() → self::FooGeneric<self::FooGeneric::X%>
+    : super core::Object::•()
+    ;
+  static factory namedFactory<X extends core::Object? = dynamic>() → self::FooGeneric<self::FooGeneric::namedFactory::X%>
+    return new self::FooGeneric::named<self::FooGeneric::namedFactory::X%>();
+}
+static const field self::Foo bar = #C3;
+static const field self::Foo bar2 = #C3;
+static const field self::FooGeneric<core::int> barGeneric = #C4;
+static const field self::FooGeneric<core::int> barGeneric2 = #C4;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::Foo::namedFactory
+  #C2 = constructor-tearoff self::FooGeneric::namedFactory
+  #C3 = self::Foo {}
+  #C4 = self::FooGeneric<core::int*> {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue47339.dart:
+- Foo.named (from org-dartlang-testcase:///issue47339.dart:6:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- FooGeneric.named (from org-dartlang-testcase:///issue47339.dart:17:9)
diff --git a/pkg/front_end/testcases/general/issue47462.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47462.dart.weak.modular.expect
new file mode 100644
index 0000000..2a6bd0b
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47462.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef MyList<T extends core::num> = core::List<T>;
+static method main() → dynamic {
+  self::expect(true, #C1);
+  self::expect(false, #C2);
+  self::expect(true, core::identical(#C4, #C4));
+  self::expect(false, core::identical(#C4, #C6));
+  (core::int, core::num, {growable: core::bool}) → core::List<core::num> v1 = #C4;
+  (core::int, core::num, {growable: core::bool}) → core::List<core::num> v2 = #C4;
+  (core::int, core::num, {growable: core::bool}) → core::List<core::num> v3 = #C6;
+  core::bool v4 = core::identical(v1, v2);
+  core::bool v5 = core::identical(v1, v3);
+  self::expect(true, v4);
+  self::expect(false, v5);
+  self::expect(true, core::identical(v1, v2));
+  self::expect(false, core::identical(v1, v3));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/array_patch.dart */ _#MyList#new#tearOff<T extends core::num>([core::int? length = #C7]) → core::List<self::_#MyList#new#tearOff::T>
+  return core::List::•<self::_#MyList#new#tearOff::T>(length);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/array_patch.dart */ _#MyList#filled#tearOff<T extends core::num>(core::int length, self::_#MyList#filled#tearOff::T fill, {core::bool growable = #C2}) → core::List<self::_#MyList#filled#tearOff::T>
+  return core::List::filled<self::_#MyList#filled#tearOff::T>(length, fill, growable: growable);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/array_patch.dart */ _#MyList#empty#tearOff<T extends core::num>({core::bool growable = #C2}) → core::List<self::_#MyList#empty#tearOff::T>
+  return core::List::empty<self::_#MyList#empty#tearOff::T>(growable: growable);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/array_patch.dart */ _#MyList#from#tearOff<T extends core::num>(core::Iterable<dynamic> elements, {core::bool growable = #C1}) → core::List<self::_#MyList#from#tearOff::T>
+  return core::List::from<self::_#MyList#from#tearOff::T>(elements, growable: growable);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/array_patch.dart */ _#MyList#of#tearOff<T extends core::num>(core::Iterable<self::_#MyList#of#tearOff::T> elements, {core::bool growable = #C1}) → core::List<self::_#MyList#of#tearOff::T>
+  return core::List::of<self::_#MyList#of#tearOff::T>(elements, growable: growable);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/array_patch.dart */ _#MyList#generate#tearOff<T extends core::num>(core::int length, (core::int) → self::_#MyList#generate#tearOff::T generator, {core::bool growable = #C1}) → core::List<self::_#MyList#generate#tearOff::T>
+  return core::List::generate<self::_#MyList#generate#tearOff::T>(length, generator, growable: growable);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/array_patch.dart */ _#MyList#unmodifiable#tearOff<T extends core::num>(core::Iterable<dynamic> elements) → core::List<self::_#MyList#unmodifiable#tearOff::T>
+  return core::List::unmodifiable<self::_#MyList#unmodifiable#tearOff::T>(elements);
+
+constants  {
+  #C1 = true
+  #C2 = false
+  #C3 = constructor-tearoff core::List::filled
+  #C4 = instantiation #C3 <core::num*>
+  #C5 = static-tearoff self::_#MyList#filled#tearOff
+  #C6 = instantiation #C5 <core::num*>
+  #C7 = null
+}
diff --git a/pkg/front_end/testcases/general/issue47495.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47495.dart.weak.modular.expect
new file mode 100644
index 0000000..aeebd16
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47495.dart.weak.modular.expect
@@ -0,0 +1,70 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue47495.dart:10:16: Error: Can't create typedef from non-function type.
+// typedef SAlias = S;
+//                ^
+//
+// pkg/front_end/testcases/general/issue47495.dart:11:16: Error: Can't create typedef from non-function type.
+// typedef MAlias = M;
+//                ^
+//
+// pkg/front_end/testcases/general/issue47495.dart:13:7: Error: The type 'MAlias' can't be mixed in.
+// class C = SAlias with MAlias;
+//       ^
+// pkg/front_end/testcases/general/issue47495.dart:11:9: Context: The issue arises via this type alias.
+// typedef MAlias = M;
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef SAlias = invalid-type;
+typedef MAlias = invalid-type;
+class S extends core::Object {
+  synthetic constructor •() → self::S*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M extends core::Object {
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue47728_1.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47728_1.dart.weak.modular.expect
new file mode 100644
index 0000000..a0401b1
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47728_1.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue47728_1.dart:7:11: Error: Can't create typedef from nullable type.
+// typedef A = Function()?;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef A = invalid-type;
+class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+}
+class C = core::Object with self::B {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue47728_2.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47728_2.dart.weak.modular.expect
new file mode 100644
index 0000000..82e50f8
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47728_2.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue47728_2.dart:5:13: Error: Expected a type, but got ';'.
+// typedef A = ;
+//             ^
+//
+// pkg/front_end/testcases/general/issue47728_2.dart:5:11: Error: Can't create typedef from non-type.
+// typedef A = ;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef A = invalid-type;
+class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+}
+class C = core::Object with self::B {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue47728_3.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47728_3.dart.weak.modular.expect
new file mode 100644
index 0000000..7f3c778
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47728_3.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue47728_3.dart:7:13: Error: Expected a type, but got ';'.
+// typedef A = ;
+//             ^
+//
+// pkg/front_end/testcases/general/issue47728_3.dart:7:11: Error: Can't create typedef from non-type.
+// typedef A = ;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef A = invalid-type;
+class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+}
+class C = core::Object with self::B {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue47728_4.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue47728_4.dart.weak.modular.expect
new file mode 100644
index 0000000..b242e08
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue47728_4.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue47728_4.dart:9:7: Error: The type 'A' which is an alias of 'dynamic Function()?' can't be used as supertype because it is nullable.
+// class C = A with B;
+//       ^
+// pkg/front_end/testcases/general/issue47728_4.dart:5:9: Context: The issue arises via this type alias.
+// typedef A = Function()?;
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef A = () →? dynamic;
+class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+}
+class C = core::Object with self::B {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/issue_46886.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue_46886.dart.weak.modular.expect
new file mode 100644
index 0000000..e64cce5
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue_46886.dart.weak.modular.expect
@@ -0,0 +1,84 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/issue_46886.dart:8:16: Error: This requires the 'triple-shift' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.14 or higher, and running 'pub get'.
+//   Foo operator >>>(_) => this;
+//                ^^^
+//
+// pkg/front_end/testcases/general/issue_46886.dart:20:7: Error: This requires the 'triple-shift' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.14 or higher, and running 'pub get'.
+//   foo >>> 42;
+//       ^^^
+//
+// pkg/front_end/testcases/general/issue_46886.dart:21:13: Error: This requires the 'triple-shift' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.14 or higher, and running 'pub get'.
+//   print(foo >>> 42);
+//             ^^^
+//
+// pkg/front_end/testcases/general/issue_46886.dart:22:13: Error: This requires the 'triple-shift' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.14 or higher, and running 'pub get'.
+//   print(foo >>>= 42);
+//             ^^^^
+//
+// pkg/front_end/testcases/general/issue_46886.dart:23:12: Error: This requires the 'triple-shift' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.14 or higher, and running 'pub get'.
+//   if ((foo >>>= 42) == foo) {
+//            ^^^^
+//
+// pkg/front_end/testcases/general/issue_46886.dart:28:13: Error: Expected an identifier, but got ')'.
+// Try inserting an identifier before ')'.
+//   print(#>>>);
+//             ^
+//
+// pkg/front_end/testcases/general/issue_46886.dart:30:14: Error: This requires the 'triple-shift' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.14 or higher, and running 'pub get'.
+//   var x = 10 >>> 2;
+//              ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → self::Foo
+    : super core::Object::•()
+    ;
+  operator >>>(dynamic _) → self::Foo
+    return this;
+}
+abstract class Bar extends core::Object implements core::List<core::List<core::List<core::String>>> {
+  synthetic constructor •() → self::Bar
+    : super core::Object::•()
+    ;
+}
+extension _extension#0 on core::Symbol {
+  operator > = self::_extension#0|>;
+  method call = self::_extension#0|call;
+  tearoff call = self::_extension#0|get#call;
+}
+static method _extension#0|>(lowered final core::Symbol #this, dynamic _) → core::String
+  return "Greater Than used";
+static method _extension#0|call(lowered final core::Symbol #this, dynamic _) → core::String
+  return "Called";
+static method _extension#0|get#call(lowered final core::Symbol #this) → (dynamic) → core::String
+  return (dynamic _) → core::String => self::_extension#0|call(#this, _);
+static method main() → dynamic {
+  self::Foo foo = new self::Foo::•();
+  foo.{self::Foo::>>>}(42){(dynamic) → self::Foo};
+  core::print(foo.{self::Foo::>>>}(42){(dynamic) → self::Foo});
+  core::print(foo = foo.{self::Foo::>>>}(42){(dynamic) → self::Foo});
+  if((foo = foo.{self::Foo::>>>}(42){(dynamic) → self::Foo}) =={core::Object::==}{(core::Object) → core::bool} foo) {
+    core::print("same");
+  }
+  core::print(self::_extension#0|>(#C1, 2));
+  core::print(self::_extension#0|>(#C1, invalid-expression "pkg/front_end/testcases/general/issue_46886.dart:28:13: Error: This couldn't be parsed.
+  print(#>>>);
+            ^"));
+  core::int x = 10.{core::int::>>>}(2){(core::int) → core::int};
+  core::print("x: ${x}");
+}
+
+constants  {
+  #C1 = #>>
+}
diff --git a/pkg/front_end/testcases/general/issue_47008_01.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue_47008_01.dart.weak.modular.expect
new file mode 100644
index 0000000..383dfab
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue_47008_01.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::int b = 1;
+  core::int c = 2;
+  core::int d = 3;
+  core::int e = 4;
+  self::a(b.{core::num::<}(c){(core::num) → core::bool}, d.{core::num::<}(e){(core::num) → core::bool}, 1.{core::int::>>}(2){(core::int) → core::int});
+}
+static method a(core::bool x, core::bool y, core::int z) → void {
+  core::print("${x} ${y} ${z}");
+}
diff --git a/pkg/front_end/testcases/general/issue_47008_02.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue_47008_02.dart.weak.modular.expect
new file mode 100644
index 0000000..d448313
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue_47008_02.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::int b = 1;
+  core::int c = 2;
+  core::int d = 3;
+  core::int e = 4;
+  core::int f = 5;
+  core::int g = 6;
+  self::a(b.{core::num::<}(c){(core::num) → core::bool}, d.{core::num::<}(e){(core::num) → core::bool}, f.{core::num::<}(g){(core::num) → core::bool}, 1.{core::int::>>>}(2){(core::int) → core::int});
+}
+static method a(core::bool x, core::bool y, core::bool z1, core::int z2) → void {
+  core::print("${x} ${y} ${z1} ${z2}");
+}
diff --git a/pkg/front_end/testcases/general/issue_47009_01.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue_47009_01.dart.weak.modular.expect
new file mode 100644
index 0000000..a9de674
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue_47009_01.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::int b = 1;
+  core::int c = 2;
+  core::int as = 3;
+  self::a(b.{core::num::<}(c){(core::num) → core::bool}, as.{core::num::>}(1){(core::num) → core::bool});
+}
+static method a(core::bool x, core::bool y) → void {
+  core::print("${x} ${y}");
+}
diff --git a/pkg/front_end/testcases/general/issue_47009_02.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue_47009_02.dart.weak.modular.expect
new file mode 100644
index 0000000..c5218bb
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue_47009_02.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::int b = 1;
+  core::int c = 2;
+  core::int d = 3;
+  core::int e = 4;
+  core::int as = 5;
+  self::a(b.{core::num::<}(c){(core::num) → core::bool}, d.{core::num::<}(e){(core::num) → core::bool}, as.{core::int::>>}(1){(core::int) → core::int});
+}
+static method a(core::bool x, core::bool y, core::int z) → void {
+  core::print("${x} ${y} ${z}");
+}
diff --git a/pkg/front_end/testcases/general/issue_47009_03.dart.weak.modular.expect b/pkg/front_end/testcases/general/issue_47009_03.dart.weak.modular.expect
new file mode 100644
index 0000000..1d366c4
--- /dev/null
+++ b/pkg/front_end/testcases/general/issue_47009_03.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::int b = 1;
+  core::int c = 2;
+  core::int d = 3;
+  core::int e = 4;
+  core::int f = 5;
+  core::int g = 6;
+  core::int as = 7;
+  self::a(b.{core::num::<}(c){(core::num) → core::bool}, d.{core::num::<}(e){(core::num) → core::bool}, f.{core::num::<}(g){(core::num) → core::bool}, as.{core::int::>>>}(1){(core::int) → core::int});
+}
+static method a(core::bool x, core::bool y, core::bool z1, core::int z2) → void {
+  core::print("${x} ${y} ${z1} ${z2}");
+}
diff --git a/pkg/front_end/testcases/general/literals.dart.weak.modular.expect b/pkg/front_end/testcases/general/literals.dart.weak.modular.expect
new file mode 100644
index 0000000..8ef3e48
--- /dev/null
+++ b/pkg/front_end/testcases/general/literals.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method testString() → dynamic {
+  core::print("a");
+}
+static method testInt() → dynamic {
+  core::print(1);
+}
+static method testBool() → dynamic {
+  core::print(true);
+  core::print(false);
+}
+static method testDouble() → dynamic {
+  core::print(1.0);
+}
+static method testNull() → dynamic {
+  core::print(null);
+}
+static method testList() → dynamic {
+  core::print(<dynamic>[]);
+  core::print(<core::String*>["a", "b"]);
+}
+static method testMap() → dynamic {
+  core::print(<dynamic, dynamic>{});
+  core::print(<core::String*, core::String*>{"a": "b"});
+}
+static method testSymbol() → dynamic {
+  core::print(#C1);
+  core::print(#C2);
+  core::print(#C3);
+}
+static method main() → dynamic {
+  self::testString();
+  self::testInt();
+  self::testBool();
+  self::testDouble();
+  self::testNull();
+  self::testList();
+  self::testMap();
+  self::testSymbol();
+}
+
+constants  {
+  #C1 = #fisk
+  #C2 = #org-dartlang-testcase:///literals.dart::_fisk
+  #C3 = #fisk.hest.ko
+}
diff --git a/pkg/front_end/testcases/general/local_generic_function.dart.weak.modular.expect b/pkg/front_end/testcases/general/local_generic_function.dart.weak.modular.expect
new file mode 100644
index 0000000..b22d5a7
--- /dev/null
+++ b/pkg/front_end/testcases/general/local_generic_function.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  function f<T extends core::Object* = dynamic>(core::List<T*>* l) → T*
+    return l.{core::List::[]}(0){(core::int*) →* T*};
+  core::int* x = f<core::int*>(<core::int*>[0]){(core::List<core::int*>*) →* core::int*};
+}
diff --git a/pkg/front_end/testcases/general/long_chain_of_typedefs.dart.weak.modular.expect b/pkg/front_end/testcases/general/long_chain_of_typedefs.dart.weak.modular.expect
new file mode 100644
index 0000000..10636b1
--- /dev/null
+++ b/pkg/front_end/testcases/general/long_chain_of_typedefs.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef Foo01<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = (Null) →* void;
+typedef Foo02<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = ((Null) →* void) →* void;
+typedef Foo03<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = (((Null) →* void) →* void) →* void;
+typedef Foo04<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = ((((Null) →* void) →* void) →* void) →* void;
+typedef Foo05<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = (((((Null) →* void) →* void) →* void) →* void) →* void;
+typedef Foo06<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = ((((((Null) →* void) →* void) →* void) →* void) →* void) →* void;
+typedef Foo07<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = (((((((Null) →* void) →* void) →* void) →* void) →* void) →* void) →* void;
+typedef Foo08<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = ((((((((Null) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void;
+typedef Foo09<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = (((((((((Null) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void;
+typedef Foo10<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = ((((((((((Null) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void;
+typedef Foo11<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = (((((((((((Null) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void;
+typedef Foo12<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = ((((((((((((Null) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void;
+typedef Foo13<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = (((((((((((((Null) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void;
+typedef Foo14<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = ((((((((((((((Null) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void;
+typedef Foo15<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = (((((((((((((((Null) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void;
+typedef Foo16<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = ((((((((((((((((Null) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void;
+typedef Foo17<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = (((((((((((((((((Null) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void;
+typedef Foo18<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = ((((((((((((((((((Null) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void;
+typedef Foo19<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = (((((((((((((((((((Null) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void;
+typedef Foo20<unrelated X extends core::Object* = dynamic, unrelated Y extends core::Object* = dynamic, unrelated Z extends core::Object* = dynamic> = ((((((((((((((((((((Null) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void) →* void;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/macro_class.dart b/pkg/front_end/testcases/general/macro_class.dart
new file mode 100644
index 0000000..36ad13f
--- /dev/null
+++ b/pkg/front_end/testcases/general/macro_class.dart
@@ -0,0 +1,13 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+class Super {}
+mixin Mixin {}
+
+macro class Class1 {}
+abstract macro class Class2 {}
+macro class Class3 = Super with Mixin;
+abstract macro class Class4 = Super with Mixin;
+
+main() {}
\ No newline at end of file
diff --git a/pkg/front_end/testcases/general/macro_class.dart.textual_outline.expect b/pkg/front_end/testcases/general/macro_class.dart.textual_outline.expect
new file mode 100644
index 0000000..d33df1d
--- /dev/null
+++ b/pkg/front_end/testcases/general/macro_class.dart.textual_outline.expect
@@ -0,0 +1,9 @@
+class Super {}
+mixin Mixin {}
+macro
+class Class1 {}
+abstract macro class Class2 {}
+macro
+class Class3 = Super with Mixin;
+abstract macro class Class4 = Super with Mixin;
+main() {}
diff --git a/pkg/front_end/testcases/general/macro_class.dart.weak.expect b/pkg/front_end/testcases/general/macro_class.dart.weak.expect
new file mode 100644
index 0000000..5a61151
--- /dev/null
+++ b/pkg/front_end/testcases/general/macro_class.dart.weak.expect
@@ -0,0 +1,55 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/macro_class.dart:8:7: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// macro class Class1 {}
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/macro_class.dart:9:16: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// abstract macro class Class2 {}
+//                ^^^^^
+//
+// pkg/front_end/testcases/general/macro_class.dart:10:7: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// macro class Class3 = Super with Mixin;
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/macro_class.dart:11:16: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// abstract macro class Class4 = Super with Mixin;
+//                ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+}
+class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+}
+abstract class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2
+    : super core::Object::•()
+    ;
+}
+class Class3 = self::Super with self::Mixin {
+  synthetic constructor •() → self::Class3
+    : super self::Super::•()
+    ;
+}
+abstract class Class4 = self::Super with self::Mixin {
+  synthetic constructor •() → self::Class4
+    : super self::Super::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/macro_class.dart.weak.modular.expect b/pkg/front_end/testcases/general/macro_class.dart.weak.modular.expect
new file mode 100644
index 0000000..5a61151
--- /dev/null
+++ b/pkg/front_end/testcases/general/macro_class.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/macro_class.dart:8:7: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// macro class Class1 {}
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/macro_class.dart:9:16: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// abstract macro class Class2 {}
+//                ^^^^^
+//
+// pkg/front_end/testcases/general/macro_class.dart:10:7: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// macro class Class3 = Super with Mixin;
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/macro_class.dart:11:16: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// abstract macro class Class4 = Super with Mixin;
+//                ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+}
+class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+}
+abstract class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2
+    : super core::Object::•()
+    ;
+}
+class Class3 = self::Super with self::Mixin {
+  synthetic constructor •() → self::Class3
+    : super self::Super::•()
+    ;
+}
+abstract class Class4 = self::Super with self::Mixin {
+  synthetic constructor •() → self::Class4
+    : super self::Super::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/macro_class.dart.weak.outline.expect b/pkg/front_end/testcases/general/macro_class.dart.weak.outline.expect
new file mode 100644
index 0000000..13e7bcc
--- /dev/null
+++ b/pkg/front_end/testcases/general/macro_class.dart.weak.outline.expect
@@ -0,0 +1,53 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/macro_class.dart:8:7: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// macro class Class1 {}
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/macro_class.dart:9:16: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// abstract macro class Class2 {}
+//                ^^^^^
+//
+// pkg/front_end/testcases/general/macro_class.dart:10:7: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// macro class Class3 = Super with Mixin;
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/macro_class.dart:11:16: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// abstract macro class Class4 = Super with Mixin;
+//                ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    ;
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+}
+class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    ;
+}
+abstract class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2
+    ;
+}
+class Class3 = self::Super with self::Mixin {
+  synthetic constructor •() → self::Class3
+    : super self::Super::•()
+    ;
+}
+abstract class Class4 = self::Super with self::Mixin {
+  synthetic constructor •() → self::Class4
+    : super self::Super::•()
+    ;
+}
+static method main() → dynamic
+  ;
diff --git a/pkg/front_end/testcases/general/macro_class.dart.weak.transformed.expect b/pkg/front_end/testcases/general/macro_class.dart.weak.transformed.expect
new file mode 100644
index 0000000..506e808
--- /dev/null
+++ b/pkg/front_end/testcases/general/macro_class.dart.weak.transformed.expect
@@ -0,0 +1,55 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/macro_class.dart:8:7: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// macro class Class1 {}
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/macro_class.dart:9:16: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// abstract macro class Class2 {}
+//                ^^^^^
+//
+// pkg/front_end/testcases/general/macro_class.dart:10:7: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// macro class Class3 = Super with Mixin;
+//       ^^^^^
+//
+// pkg/front_end/testcases/general/macro_class.dart:11:16: Error: This requires the 'macros' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.16 or higher, and running 'pub get'.
+// abstract macro class Class4 = Super with Mixin;
+//                ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+}
+class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+}
+abstract class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2
+    : super core::Object::•()
+    ;
+}
+class Class3 extends self::Super implements self::Mixin /*isEliminatedMixin*/  {
+  synthetic constructor •() → self::Class3
+    : super self::Super::•()
+    ;
+}
+abstract class Class4 extends self::Super implements self::Mixin /*isEliminatedMixin*/  {
+  synthetic constructor •() → self::Class4
+    : super self::Super::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/magic_const.dart.weak.modular.expect b/pkg/front_end/testcases/general/magic_const.dart.weak.modular.expect
new file mode 100644
index 0000000..60dcd8b
--- /dev/null
+++ b/pkg/front_end/testcases/general/magic_const.dart.weak.modular.expect
@@ -0,0 +1,81 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/magic_const.dart:15:9: Error: Constant expression expected.
+// Try inserting 'const'.
+// foo({a: Constant(), b: Constant(), c: []}) {}
+//         ^^^^^^^^
+//
+// pkg/front_end/testcases/general/magic_const.dart:15:24: Error: Constant expression expected.
+// Try inserting 'const'.
+// foo({a: Constant(), b: Constant(), c: []}) {}
+//                        ^^^^^^^^
+//
+// pkg/front_end/testcases/general/magic_const.dart:15:39: Error: Constant expression expected.
+// Try inserting 'const'.
+// foo({a: Constant(), b: Constant(), c: []}) {}
+//                                       ^
+//
+// pkg/front_end/testcases/general/magic_const.dart:18:9: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+// Try using a constructor or factory that is 'const'.
+//   const NotConstant();
+//         ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/magic_const.dart:15:39: Error: Non-constant list literal is not a constant expression.
+// foo({a: Constant(), b: Constant(), c: []}) {}
+//                                       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Constant extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::Constant*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class NotConstant extends core::Object {
+  synthetic constructor •() → self::NotConstant*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo({dynamic a = #C1, dynamic b = #C1, dynamic c = invalid-expression "Non-constant list literal is not a constant expression."}) → dynamic {}
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/magic_const.dart:18:9: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+Try using a constructor or factory that is 'const'.
+  const NotConstant();
+        ^^^^^^^^^^^";
+  new self::Constant::•();
+  core::bool::fromEnvironment("fisk");
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Constant {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///magic_const.dart:
+- Constant. (from org-dartlang-testcase:///magic_const.dart:10:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/main_declaration.dart.weak.modular.expect b/pkg/front_end/testcases/general/main_declaration.dart.weak.modular.expect
new file mode 100644
index 0000000..58118e1
--- /dev/null
+++ b/pkg/front_end/testcases/general/main_declaration.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library;
+import self as self;
+
+import "org-dartlang-testcase:///main_declaration_lib.dart";
+
+static method main() → dynamic {}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+static method main(core::String* args) → dynamic {}
diff --git a/pkg/front_end/testcases/general/many_errors.dart.weak.modular.expect b/pkg/front_end/testcases/general/many_errors.dart.weak.modular.expect
new file mode 100644
index 0000000..48ce15f
--- /dev/null
+++ b/pkg/front_end/testcases/general/many_errors.dart.weak.modular.expect
@@ -0,0 +1,144 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/many_errors.dart:8:3: Error: A const constructor can't have a body.
+// Try removing either the 'const' keyword or the body.
+//   const A.named1() sync* {}
+//   ^^^^^
+//
+// pkg/front_end/testcases/general/many_errors.dart:13:1: Error: An external or native method can't have a body.
+// external foo(String x) {
+// ^^^^^^^^
+//
+// pkg/front_end/testcases/general/many_errors.dart:10:26: Error: New expression is not a constant expression.
+//   const A.named2() : x = new Object();
+//                          ^^^
+//
+// pkg/front_end/testcases/general/many_errors.dart:10:24: Error: 'x' is a final instance variable that was initialized at the declaration.
+//   const A.named2() : x = new Object();
+//                        ^
+// pkg/front_end/testcases/general/many_errors.dart:6:9: Context: 'x' was initialized here.
+//   final x = null;
+//         ^
+//
+// pkg/front_end/testcases/general/many_errors.dart:10:24: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+// Try using a constructor or factory that is 'const'.
+//   const A.named2() : x = new Object();
+//                        ^
+//
+// pkg/front_end/testcases/general/many_errors.dart:8:26: Error: Constructor bodies can't use 'async', 'async*', or 'sync*'.
+//   const A.named1() sync* {}
+//                          ^
+//
+// pkg/front_end/testcases/general/many_errors.dart:13:24: Error: An external or native method can't have a body.
+// external foo(String x) {
+//                        ^
+//
+// pkg/front_end/testcases/general/many_errors.dart:28:9: Error: The class 'AbstractClass' is abstract and can't be instantiated.
+//   const AbstractClass.id();
+//         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/many_errors.dart:28:9: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+// Try using a constructor or factory that is 'const'.
+//   const AbstractClass.id();
+//         ^
+//
+// pkg/front_end/testcases/general/many_errors.dart:29:28: Error: The getter 'b' isn't defined for the class 'B'.
+//  - 'B' is from 'pkg/front_end/testcases/general/many_errors.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'b'.
+//   (new C()?.b ??= new B()).b;
+//                            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  final field dynamic x = null;
+  constructor named1() → self::A*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/many_errors.dart:8:26: Error: Constructor bodies can't use 'async', 'async*', or 'sync*'.
+  const A.named1() sync* {}
+                         ^" {}
+  const constructor named2() → self::A*
+    : final dynamic #t2 = throw invalid-expression "pkg/front_end/testcases/general/many_errors.dart:10:24: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+Try using a constructor or factory that is 'const'.
+  const A.named2() : x = new Object();
+                       ^", super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  field self::B* b = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class AbstractClass extends core::Object /*hasConstConstructor*/  {
+  const constructor id() → self::AbstractClass*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+external static method foo(core::String* x) → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/many_errors.dart:13:24: Error: An external or native method can't have a body.
+external foo(String x) {
+                       ^";
+  {
+    return x.{core::String::length}{core::int*};
+  }
+}
+static method m() → dynamic {
+  throw invalid-expression "pkg/front_end/testcases/general/many_errors.dart:28:9: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+Try using a constructor or factory that is 'const'.
+  const AbstractClass.id();
+        ^";
+  invalid-expression "pkg/front_end/testcases/general/many_errors.dart:29:28: Error: The getter 'b' isn't defined for the class 'B'.
+ - 'B' is from 'pkg/front_end/testcases/general/many_errors.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'b'.
+  (new C()?.b ??= new B()).b;
+                           ^" in (let final self::C* #t3 = new self::C::•() in #t3 == null ?{self::B*} null : let final self::B* #t4 = #t3.{self::C::b}{self::B*} in #t4 == null ?{self::B*} #t3.{self::C::b} = new self::B::•() : #t4){<unresolved>}.b;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/map.dart.weak.modular.expect b/pkg/front_end/testcases/general/map.dart.weak.modular.expect
new file mode 100644
index 0000000..c82d4a6
--- /dev/null
+++ b/pkg/front_end/testcases/general/map.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::print(core::Map::•<dynamic, dynamic>());
+}
diff --git a/pkg/front_end/testcases/general/metadata_enum.dart.weak.modular.expect b/pkg/front_end/testcases/general/metadata_enum.dart.weak.modular.expect
new file mode 100644
index 0000000..a1967bf
--- /dev/null
+++ b/pkg/front_end/testcases/general/metadata_enum.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+@#C1
+class E extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::E*>* values = #C11;
+  static const field self::E* E1 = #C4;
+  static const field self::E* E2 = #C7;
+  static const field self::E* E3 = #C10;
+  const constructor •(core::int* index, core::String* name) → self::E*
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String*
+    return "E.${this.{core::_Enum::_name}{core::String}}";
+  abstract member-signature get index() → core::int*; -> core::_Enum::index
+  abstract member-signature get _name() → core::String*; -> core::_Enum::_name
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field dynamic a = #C1;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = 0
+  #C3 = "E1"
+  #C4 = self::E {index:#C2, _name:#C3}
+  #C5 = 1
+  #C6 = "E2"
+  #C7 = self::E {index:#C5, _name:#C6}
+  #C8 = 2
+  #C9 = "E3"
+  #C10 = self::E {index:#C8, _name:#C9}
+  #C11 = <self::E*>[#C4, #C7, #C10]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///metadata_enum.dart:
+- E. (from org-dartlang-testcase:///metadata_enum.dart:8:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:76:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/metadata_named_mixin_application.dart.weak.modular.expect b/pkg/front_end/testcases/general/metadata_named_mixin_application.dart.weak.modular.expect
new file mode 100644
index 0000000..02845a0
--- /dev/null
+++ b/pkg/front_end/testcases/general/metadata_named_mixin_application.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+@#C1
+class C = self::D with self::E {
+  synthetic constructor •() → self::C*
+    : super self::D::•()
+    ;
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E extends core::Object {
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field dynamic a = #C1;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/method_tearoff_covariant_generic_type_check.dart.weak.modular.expect b/pkg/front_end/testcases/general/method_tearoff_covariant_generic_type_check.dart.weak.modular.expect
new file mode 100644
index 0000000..a99c84b
--- /dev/null
+++ b/pkg/front_end/testcases/general/method_tearoff_covariant_generic_type_check.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::num> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X>
+    : super core::Object::•()
+    ;
+  method f<covariant-by-class Y extends self::A::X>(self::A::f::Y y) → void {}
+}
+static method expectThrows(() → void f) → dynamic {
+  try {
+    f(){() → void};
+  }
+  on core::Object catch(final core::Object e) {
+    return;
+  }
+  throw "Expected an exception to be thrown!";
+}
+static method main() → dynamic {
+  self::A<core::num> a = new self::A::•<core::int>();
+  self::expectThrows(() → void {
+    <Y extends core::num>(Y) → void f = a.{self::A::f}{<covariant-by-class Y extends core::num>(Y) → void} as{TypeError,CovarianceCheck,ForNonNullableByDefault} <covariant-by-class Y extends core::num>(Y) → void;
+  });
+}
diff --git a/pkg/front_end/testcases/general/method_tearoff_covariant_generic_type_check_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/general/method_tearoff_covariant_generic_type_check_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..090dbcd
--- /dev/null
+++ b/pkg/front_end/testcases/general/method_tearoff_covariant_generic_type_check_opt_out.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::num*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  method f<covariant-by-class Y extends self::A::X*>(self::A::f::Y* y) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method expectThrows(() →* void f) → dynamic {
+  try {
+    f(){() →* void};
+  }
+  on dynamic catch(final dynamic e) {
+    return;
+  }
+  throw "Expected an exception to be thrown!";
+}
+static method main() → dynamic {
+  self::A<core::num*>* a = new self::A::•<core::int*>();
+  <Y extends core::num*>(Y*) →* void f = a.{self::A::f}{<covariant-by-class Y extends core::num*>(Y*) →* void};
+  self::expectThrows(() → Null {
+    f<core::double*>(3.14){(core::double*) →* void};
+  });
+}
diff --git a/pkg/front_end/testcases/general/micro.dart.weak.modular.expect b/pkg/front_end/testcases/general/micro.dart.weak.modular.expect
new file mode 100644
index 0000000..8bd8f18
--- /dev/null
+++ b/pkg/front_end/testcases/general/micro.dart.weak.modular.expect
@@ -0,0 +1,151 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  method instanceMethod() → dynamic {
+    return 123;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class ExternalValue extends core::Object {
+  synthetic constructor •() → self::ExternalValue*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Bar extends core::Object {
+  synthetic constructor •() → self::Bar*
+    : super core::Object::•()
+    ;
+  abstract method externalInstanceMethod() → self::ExternalValue*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Box extends core::Object {
+  field dynamic field = null;
+  synthetic constructor •() → self::Box*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class FinalBox extends core::Object {
+  final field dynamic finalField;
+  constructor •(dynamic finalField) → self::FinalBox*
+    : self::FinalBox::finalField = finalField, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class SubFinalBox extends self::FinalBox {
+  constructor •(dynamic value) → self::SubFinalBox*
+    : super self::FinalBox::•(value)
+    ;
+}
+class DynamicReceiver1 extends core::Object {
+  synthetic constructor •() → self::DynamicReceiver1*
+    : super core::Object::•()
+    ;
+  method dynamicallyCalled(dynamic x) → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class DynamicReceiver2 extends core::Object {
+  synthetic constructor •() → self::DynamicReceiver2*
+    : super core::Object::•()
+    ;
+  method dynamicallyCalled(dynamic x) → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method staticMethod() → dynamic {
+  return "sdfg";
+}
+external static method externalStatic() → core::bool*;
+external static method createBar() → self::Bar*;
+static method stringArgument(dynamic x) → dynamic {}
+static method intArgument(dynamic x) → dynamic {}
+static method makeDynamicCall(dynamic receiver) → void {
+  receiver{dynamic}.dynamicallyCalled("sdfg");
+}
+static method main() → dynamic {
+  dynamic x = self::staticMethod();
+  dynamic y = new self::Foo::•().{self::Foo::instanceMethod}(){() →* dynamic};
+  core::bool* z = self::externalStatic();
+  self::ExternalValue* w = self::createBar().{self::Bar::externalInstanceMethod}(){() →* self::ExternalValue*};
+  self::stringArgument("sdfg");
+  self::intArgument(42);
+  self::Box* box = new self::Box::•();
+  box.{self::Box::field} = "sdfg";
+  dynamic a = box.{self::Box::field}{dynamic};
+  self::FinalBox* finalBox = new self::FinalBox::•("dfg");
+  dynamic b = finalBox.{self::FinalBox::finalField}{dynamic};
+  self::SubFinalBox* subBox = new self::SubFinalBox::•("dfg");
+  dynamic c = subBox.{self::FinalBox::finalField}{dynamic};
+  self::makeDynamicCall(new self::DynamicReceiver1::•());
+  self::makeDynamicCall(new self::DynamicReceiver2::•());
+  core::List<core::String*>* list = <core::String*>["string"];
+  core::String* d = list.{core::List::[]}(0){(core::int*) →* core::String*};
+}
diff --git a/pkg/front_end/testcases/general/minimum_int.dart.weak.modular.expect b/pkg/front_end/testcases/general/minimum_int.dart.weak.modular.expect
new file mode 100644
index 0000000..65f7c38
--- /dev/null
+++ b/pkg/front_end/testcases/general/minimum_int.dart.weak.modular.expect
@@ -0,0 +1,6 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic
+  return core::print(-9223372036854775808.{core::int::unary-}(){() →* core::int*});
diff --git a/pkg/front_end/testcases/general/missing_constructor.dart.weak.modular.expect b/pkg/front_end/testcases/general/missing_constructor.dart.weak.modular.expect
new file mode 100644
index 0000000..12e92e5
--- /dev/null
+++ b/pkg/front_end/testcases/general/missing_constructor.dart.weak.modular.expect
@@ -0,0 +1,113 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/missing_constructor.dart:10:11: Error: Superclass has no constructor named 'Super'.
+//   Sub() : super();
+//           ^^^^^
+//
+// pkg/front_end/testcases/general/missing_constructor.dart:11:15: Error: Superclass has no constructor named 'Super.foo'.
+//   Sub.foo() : super.foo();
+//               ^^^^^
+//
+// pkg/front_end/testcases/general/missing_constructor.dart:15:15: Error: Couldn't find constructor 'Bad'.
+//   Bad.foo() : this();
+//               ^^^^
+//
+// pkg/front_end/testcases/general/missing_constructor.dart:16:15: Error: Couldn't find constructor 'Bad.baz'.
+//   Bad.bar() : this.baz();
+//               ^^^^
+//
+// pkg/front_end/testcases/general/missing_constructor.dart:22:24: Error: Superclass has no constructor named 'Super'.
+//   MixinApplication() : super();
+//                        ^^^^^
+//
+// pkg/front_end/testcases/general/missing_constructor.dart:23:28: Error: Superclass has no constructor named 'Super.foo'.
+//   MixinApplication.foo() : super.foo();
+//                            ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  constructor _() → self::Super*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Sub extends self::Super {
+  constructor •() → self::Sub*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/missing_constructor.dart:10:11: Error: Superclass has no constructor named 'Super'.
+  Sub() : super();
+          ^^^^^"
+    ;
+  constructor foo() → self::Sub*
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/general/missing_constructor.dart:11:15: Error: Superclass has no constructor named 'Super.foo'.
+  Sub.foo() : super.foo();
+              ^^^^^"
+    ;
+}
+class Bad extends core::Object {
+  constructor foo() → self::Bad*
+    : final dynamic #t3 = invalid-expression "pkg/front_end/testcases/general/missing_constructor.dart:15:15: Error: Couldn't find constructor 'Bad'.
+  Bad.foo() : this();
+              ^^^^"
+    ;
+  constructor bar() → self::Bad*
+    : final dynamic #t4 = invalid-expression "pkg/front_end/testcases/general/missing_constructor.dart:16:15: Error: Couldn't find constructor 'Bad.baz'.
+  Bad.bar() : this.baz();
+              ^^^^"
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M extends core::Object {
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _MixinApplication&Super&M = self::Super with self::M /*isAnonymousMixin*/  {
+  synthetic constructor _() → self::_MixinApplication&Super&M*
+    : super self::Super::_()
+    ;
+}
+class MixinApplication extends self::_MixinApplication&Super&M {
+  constructor •() → self::MixinApplication*
+    : final dynamic #t5 = invalid-expression "pkg/front_end/testcases/general/missing_constructor.dart:22:24: Error: Superclass has no constructor named 'Super'.
+  MixinApplication() : super();
+                       ^^^^^"
+    ;
+  constructor foo() → self::MixinApplication*
+    : final dynamic #t6 = invalid-expression "pkg/front_end/testcases/general/missing_constructor.dart:23:28: Error: Superclass has no constructor named 'Super.foo'.
+  MixinApplication.foo() : super.foo();
+                           ^^^^^"
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/missing_prefix_name.dart.weak.modular.expect b/pkg/front_end/testcases/general/missing_prefix_name.dart.weak.modular.expect
new file mode 100644
index 0000000..fc75ee08
--- /dev/null
+++ b/pkg/front_end/testcases/general/missing_prefix_name.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/missing_prefix_name.dart:5:37: Error: Expected an identifier, but got ';'.
+// Try inserting an identifier before ';'.
+// import "missing_prefix_name.dart" as;
+//                                     ^
+//
+import self as self;
+
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/missing_toplevel.dart.weak.modular.expect b/pkg/front_end/testcases/general/missing_toplevel.dart.weak.modular.expect
new file mode 100644
index 0000000..e4cac82
--- /dev/null
+++ b/pkg/front_end/testcases/general/missing_toplevel.dart.weak.modular.expect
@@ -0,0 +1,131 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/missing_toplevel.dart:27:48: Error: The operator '+' isn't defined for the class 'EmptyClass'.
+//  - 'EmptyClass' is from 'pkg/front_end/testcases/general/missing_toplevel.dart'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+// var missingBinary = classWithProperty.property += 2;
+//                                                ^
+//
+// pkg/front_end/testcases/general/missing_toplevel.dart:28:40: Error: The operator '[]' isn't defined for the class 'ClassWithIndexSet'.
+//  - 'ClassWithIndexSet' is from 'pkg/front_end/testcases/general/missing_toplevel.dart'.
+// Try correcting the operator to an existing operator, or defining a '[]' operator.
+// var missingIndexGet = classWithIndexSet[0] ??= 2;
+//                                        ^
+//
+// pkg/front_end/testcases/general/missing_toplevel.dart:29:40: Error: The operator '[]=' isn't defined for the class 'ClassWithIndexGet'.
+//  - 'ClassWithIndexGet' is from 'pkg/front_end/testcases/general/missing_toplevel.dart'.
+// Try correcting the operator to an existing operator, or defining a '[]=' operator.
+// var missingIndexSet = classWithIndexGet[0] ??= 2;
+//                                        ^
+//
+// pkg/front_end/testcases/general/missing_toplevel.dart:30:37: Error: The getter 'property' isn't defined for the class 'EmptyClass'.
+//  - 'EmptyClass' is from 'pkg/front_end/testcases/general/missing_toplevel.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'property'.
+// var missingPropertyGet = emptyClass.property;
+//                                     ^^^^^^^^
+//
+// pkg/front_end/testcases/general/missing_toplevel.dart:31:37: Error: The setter 'property' isn't defined for the class 'EmptyClass'.
+//  - 'EmptyClass' is from 'pkg/front_end/testcases/general/missing_toplevel.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'property'.
+// var missingPropertySet = emptyClass.property = 42;
+//                                     ^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class EmptyClass extends core::Object {
+  synthetic constructor •() → self::EmptyClass*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class ClassWithProperty extends core::Object {
+  field self::EmptyClass* property = null;
+  synthetic constructor •() → self::ClassWithProperty*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class ClassWithIndexSet extends core::Object {
+  synthetic constructor •() → self::ClassWithIndexSet*
+    : super core::Object::•()
+    ;
+  operator []=(core::int* index, core::int* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class ClassWithIndexGet extends core::Object {
+  synthetic constructor •() → self::ClassWithIndexGet*
+    : super core::Object::•()
+    ;
+  operator [](core::int* index) → core::int*
+    return 42;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::EmptyClass* emptyClass = new self::EmptyClass::•();
+static field self::ClassWithProperty* classWithProperty = new self::ClassWithProperty::•();
+static field self::ClassWithIndexSet* classWithIndexSet = new self::ClassWithIndexSet::•();
+static field self::ClassWithIndexGet* classWithIndexGet = new self::ClassWithIndexGet::•();
+static field dynamic missingBinary = let final self::ClassWithProperty* #t1 = self::classWithProperty in #t1.{self::ClassWithProperty::property} = invalid-expression "pkg/front_end/testcases/general/missing_toplevel.dart:27:48: Error: The operator '+' isn't defined for the class 'EmptyClass'.
+ - 'EmptyClass' is from 'pkg/front_end/testcases/general/missing_toplevel.dart'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+var missingBinary = classWithProperty.property += 2;
+                                               ^" in #t1.{self::ClassWithProperty::property}{self::EmptyClass*}{<unresolved>}.+(2) as{TypeError,ForDynamic} self::EmptyClass*;
+static field dynamic missingIndexGet = let final self::ClassWithIndexSet* #t2 = self::classWithIndexSet in let final core::int* #t3 = 0 in let final dynamic #t4 = invalid-expression "pkg/front_end/testcases/general/missing_toplevel.dart:28:40: Error: The operator '[]' isn't defined for the class 'ClassWithIndexSet'.
+ - 'ClassWithIndexSet' is from 'pkg/front_end/testcases/general/missing_toplevel.dart'.
+Try correcting the operator to an existing operator, or defining a '[]' operator.
+var missingIndexGet = classWithIndexSet[0] ??= 2;
+                                       ^" in #t2{<unresolved>}.[](#t3) in #t4 == null ?{dynamic} let final core::int* #t5 = 2 in let final void #t6 = #t2.{self::ClassWithIndexSet::[]=}(#t3, #t5){(core::int*, core::int*) →* void} in #t5 : #t4;
+static field core::int* missingIndexSet = let final self::ClassWithIndexGet* #t7 = self::classWithIndexGet in let final core::int* #t8 = 0 in let final core::int* #t9 = #t7.{self::ClassWithIndexGet::[]}(#t8){(core::int*) →* core::int*} in #t9 == null ?{core::int*} let final core::int* #t10 = 2 in let final void #t11 = invalid-expression "pkg/front_end/testcases/general/missing_toplevel.dart:29:40: Error: The operator '[]=' isn't defined for the class 'ClassWithIndexGet'.
+ - 'ClassWithIndexGet' is from 'pkg/front_end/testcases/general/missing_toplevel.dart'.
+Try correcting the operator to an existing operator, or defining a '[]=' operator.
+var missingIndexSet = classWithIndexGet[0] ??= 2;
+                                       ^" in #t7{<unresolved>}.[]=(#t8, #t10) in #t10 : #t9;
+static field dynamic missingPropertyGet = invalid-expression "pkg/front_end/testcases/general/missing_toplevel.dart:30:37: Error: The getter 'property' isn't defined for the class 'EmptyClass'.
+ - 'EmptyClass' is from 'pkg/front_end/testcases/general/missing_toplevel.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'property'.
+var missingPropertyGet = emptyClass.property;
+                                    ^^^^^^^^" in self::emptyClass{<unresolved>}.property;
+static field core::int* missingPropertySet = invalid-expression "pkg/front_end/testcases/general/missing_toplevel.dart:31:37: Error: The setter 'property' isn't defined for the class 'EmptyClass'.
+ - 'EmptyClass' is from 'pkg/front_end/testcases/general/missing_toplevel.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'property'.
+var missingPropertySet = emptyClass.property = 42;
+                                    ^^^^^^^^" in self::emptyClass{<unresolved>}.property = 42;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/mixin.dart.weak.modular.expect b/pkg/front_end/testcases/general/mixin.dart.weak.modular.expect
new file mode 100644
index 0000000..9ec9ad2d
--- /dev/null
+++ b/pkg/front_end/testcases/general/mixin.dart.weak.modular.expect
@@ -0,0 +1,142 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class _B&Object&M1 = core::Object with self::M1 /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_B&Object&M1*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method m() → dynamic
+    return super.{self::M1::m}();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _B&Object&M1&M2 = self::_B&Object&M1 with self::M2 /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_B&Object&M1&M2*
+    : super self::_B&Object&M1::•()
+    ;
+  mixin-super-stub method m() → dynamic
+    return super.{self::M2::m}();
+}
+class B extends self::_B&Object&M1&M2 {
+  constructor •(dynamic value) → self::B*
+    : super self::_B&Object&M1&M2::•()
+    ;
+}
+abstract class M1 extends core::Object {
+  synthetic constructor •() → self::M1*
+    : super core::Object::•()
+    ;
+  method m() → dynamic
+    return core::print("M1");
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M2 extends core::Object {
+  synthetic constructor •() → self::M2*
+    : super core::Object::•()
+    ;
+  method m() → dynamic
+    return core::print("M2");
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&Object&M1 = core::Object with self::M1 /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&M1*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method m() → dynamic
+    return super.{self::M1::m}();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&Object&M1&M2 = self::_C&Object&M1 with self::M2 /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&M1&M2*
+    : super self::_C&Object&M1::•()
+    ;
+  mixin-super-stub method m() → dynamic
+    return super.{self::M2::m}();
+}
+class C extends self::_C&Object&M1&M2 {
+  constructor •(dynamic value) → self::C*
+    : super self::_C&Object&M1&M2::•()
+    ;
+}
+abstract class G1<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::G1<self::G1::T*>*
+    : super core::Object::•()
+    ;
+  method m() → dynamic
+    return core::print(self::G1::T*);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _D&Object&G1<S extends core::Object* = dynamic> = core::Object with self::G1<self::_D&Object&G1::S*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_D&Object&G1<self::_D&Object&G1::S*>*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method m() → dynamic
+    return super.{self::G1::m}();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<S extends core::Object* = dynamic> extends self::_D&Object&G1<self::D::S*> {
+  synthetic constructor •() → self::D<self::D::S*>*
+    : super self::_D&Object&G1::•()
+    ;
+}
+static method main() → dynamic {
+  new self::B::•(null).{self::_B&Object&M1&M2::m}(){() →* dynamic};
+  new self::C::•(null).{self::_C&Object&M1&M2::m}(){() →* dynamic};
+  new self::D::•<dynamic>().{self::_D&Object&G1::m}(){() →* dynamic};
+  new self::D::•<core::int*>().{self::_D&Object&G1::m}(){() →* dynamic};
+  new self::D::•<core::List<core::int*>*>().{self::_D&Object&G1::m}(){() →* dynamic};
+}
diff --git a/pkg/front_end/testcases/general/mixin_application_inferred_parameter_type.dart.weak.modular.expect b/pkg/front_end/testcases/general/mixin_application_inferred_parameter_type.dart.weak.modular.expect
new file mode 100644
index 0000000..c6579d8
--- /dev/null
+++ b/pkg/front_end/testcases/general/mixin_application_inferred_parameter_type.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/mixin_application_inferred_parameter_type.dart:20:13: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//   new Class('');
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Mixin extends core::Object {
+  synthetic constructor •() → self::Mixin*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Super extends core::Object {
+  field core::int* field = 42;
+  constructor •(core::int* field) → self::Super*
+    : self::Super::field = field, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class = self::Super with self::Mixin {
+  synthetic constructor •(core::int* field) → self::Class*
+    : super self::Super::•(field)
+    ;
+}
+static method main() → dynamic {
+  new self::Class::•(0);
+}
+static method error() → dynamic {
+  new self::Class::•(invalid-expression "pkg/front_end/testcases/general/mixin_application_inferred_parameter_type.dart:20:13: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+  new Class('');
+            ^" in "" as{TypeError} core::int*);
+}
diff --git a/pkg/front_end/testcases/general/mixin_application_lub.dart.weak.modular.expect b/pkg/front_end/testcases/general/mixin_application_lub.dart.weak.modular.expect
new file mode 100644
index 0000000..8972ec3
--- /dev/null
+++ b/pkg/front_end/testcases/general/mixin_application_lub.dart.weak.modular.expect
@@ -0,0 +1,78 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Diagnosticable extends core::Object {
+  synthetic constructor •() → self::Diagnosticable*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _SomeClass&Object&Diagnosticable = core::Object with self::Diagnosticable /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_SomeClass&Object&Diagnosticable*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class SomeClass extends self::_SomeClass&Object&Diagnosticable {
+  synthetic constructor •() → self::SomeClass*
+    : super self::_SomeClass&Object&Diagnosticable::•()
+    ;
+}
+abstract class _State&Object&Diagnosticable = core::Object with self::Diagnosticable /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_State&Object&Diagnosticable*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class State<T extends core::Object* = dynamic> extends self::_State&Object&Diagnosticable {
+  synthetic constructor •() → self::State<self::State::T*>*
+    : super self::_State&Object&Diagnosticable::•()
+    ;
+}
+class StateA extends self::State<dynamic> {
+  synthetic constructor •() → self::StateA*
+    : super self::State::•()
+    ;
+}
+class StateB extends self::State<core::int*> {
+  synthetic constructor •() → self::StateB*
+    : super self::State::•()
+    ;
+}
+static field self::StateA* a = new self::StateA::•();
+static field self::StateB* b = new self::StateB::•();
+static method foo<T extends core::Object* = dynamic>(self::foo::T* x) → dynamic {
+  core::print(self::foo::T*);
+}
+static method main() → dynamic {
+  self::Diagnosticable* x = let final self::StateA* #t1 = self::a in #t1 == null ?{self::Diagnosticable*} self::b : #t1;
+  self::foo<self::Diagnosticable*>(x);
+}
diff --git a/pkg/front_end/testcases/general/mixin_application_override.dart.weak.modular.expect b/pkg/front_end/testcases/general/mixin_application_override.dart.weak.modular.expect
new file mode 100644
index 0000000..56cdffa
--- /dev/null
+++ b/pkg/front_end/testcases/general/mixin_application_override.dart.weak.modular.expect
@@ -0,0 +1,413 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/mixin_application_override.dart:21:7: Error: The mixin application class 'A0' introduces an erroneous override of 'foo'.
+// class A0 = S with M;
+//       ^^
+// pkg/front_end/testcases/general/mixin_application_override.dart:12:3: Context: The method 'M.foo' has fewer positional arguments than those of overridden method 'S.foo'.
+//   foo() {}
+//   ^
+// pkg/front_end/testcases/general/mixin_application_override.dart:8:3: Context: This is the overridden method ('foo').
+//   foo([x]) {}
+//   ^
+//
+// pkg/front_end/testcases/general/mixin_application_override.dart:22:7: Error: The mixin application class 'A1' introduces an erroneous override of 'foo'.
+// class A1 = S with M1, M;
+//       ^^
+// pkg/front_end/testcases/general/mixin_application_override.dart:12:3: Context: The method 'M.foo' has fewer positional arguments than those of overridden method 'S.foo'.
+//   foo() {}
+//   ^
+// pkg/front_end/testcases/general/mixin_application_override.dart:8:3: Context: This is the overridden method ('foo').
+//   foo([x]) {}
+//   ^
+//
+// pkg/front_end/testcases/general/mixin_application_override.dart:23:7: Error: The mixin application class 'A2' introduces an erroneous override of 'foo'.
+// class A2 = S with M1, M2, M;
+//       ^^
+// pkg/front_end/testcases/general/mixin_application_override.dart:12:3: Context: The method 'M.foo' has fewer positional arguments than those of overridden method 'S.foo'.
+//   foo() {}
+//   ^
+// pkg/front_end/testcases/general/mixin_application_override.dart:8:3: Context: This is the overridden method ('foo').
+//   foo([x]) {}
+//   ^
+//
+// pkg/front_end/testcases/general/mixin_application_override.dart:25:7: Error: Applying the mixin 'M' to 'S' introduces an erroneous override of 'foo'.
+// class A0X = S with M, MX;
+//       ^^^
+// pkg/front_end/testcases/general/mixin_application_override.dart:12:3: Context: The method 'M.foo' has fewer positional arguments than those of overridden method 'S.foo'.
+//   foo() {}
+//   ^
+// pkg/front_end/testcases/general/mixin_application_override.dart:8:3: Context: This is the overridden method ('foo').
+//   foo([x]) {}
+//   ^
+//
+// pkg/front_end/testcases/general/mixin_application_override.dart:26:7: Error: Applying the mixin 'M' to 'S with M1' introduces an erroneous override of 'foo'.
+// class A1X = S with M1, M, MX;
+//       ^^^
+// pkg/front_end/testcases/general/mixin_application_override.dart:12:3: Context: The method 'M.foo' has fewer positional arguments than those of overridden method 'S.foo'.
+//   foo() {}
+//   ^
+// pkg/front_end/testcases/general/mixin_application_override.dart:8:3: Context: This is the overridden method ('foo').
+//   foo([x]) {}
+//   ^
+//
+// pkg/front_end/testcases/general/mixin_application_override.dart:27:7: Error: Applying the mixin 'M' to 'S with M1, M2' introduces an erroneous override of 'foo'.
+// class A2X = S with M1, M2, M, MX;
+//       ^^^
+// pkg/front_end/testcases/general/mixin_application_override.dart:12:3: Context: The method 'M.foo' has fewer positional arguments than those of overridden method 'S.foo'.
+//   foo() {}
+//   ^
+// pkg/front_end/testcases/general/mixin_application_override.dart:8:3: Context: This is the overridden method ('foo').
+//   foo([x]) {}
+//   ^
+//
+// pkg/front_end/testcases/general/mixin_application_override.dart:29:7: Error: Applying the mixin 'M' to 'S' introduces an erroneous override of 'foo'.
+// class B0 extends S with M {}
+//       ^^
+// pkg/front_end/testcases/general/mixin_application_override.dart:12:3: Context: The method 'M.foo' has fewer positional arguments than those of overridden method 'S.foo'.
+//   foo() {}
+//   ^
+// pkg/front_end/testcases/general/mixin_application_override.dart:8:3: Context: This is the overridden method ('foo').
+//   foo([x]) {}
+//   ^
+//
+// pkg/front_end/testcases/general/mixin_application_override.dart:31:7: Error: Applying the mixin 'M' to 'S with M1' introduces an erroneous override of 'foo'.
+// class B1 extends S with M1, M {}
+//       ^^
+// pkg/front_end/testcases/general/mixin_application_override.dart:12:3: Context: The method 'M.foo' has fewer positional arguments than those of overridden method 'S.foo'.
+//   foo() {}
+//   ^
+// pkg/front_end/testcases/general/mixin_application_override.dart:8:3: Context: This is the overridden method ('foo').
+//   foo([x]) {}
+//   ^
+//
+// pkg/front_end/testcases/general/mixin_application_override.dart:33:7: Error: Applying the mixin 'M' to 'S with M1, M2' introduces an erroneous override of 'foo'.
+// class B2 extends S with M1, M2, M {}
+//       ^^
+// pkg/front_end/testcases/general/mixin_application_override.dart:12:3: Context: The method 'M.foo' has fewer positional arguments than those of overridden method 'S.foo'.
+//   foo() {}
+//   ^
+// pkg/front_end/testcases/general/mixin_application_override.dart:8:3: Context: This is the overridden method ('foo').
+//   foo([x]) {}
+//   ^
+//
+// pkg/front_end/testcases/general/mixin_application_override.dart:35:7: Error: Applying the mixin 'M' to 'S' introduces an erroneous override of 'foo'.
+// class B0X extends S with M, MX {}
+//       ^^^
+// pkg/front_end/testcases/general/mixin_application_override.dart:12:3: Context: The method 'M.foo' has fewer positional arguments than those of overridden method 'S.foo'.
+//   foo() {}
+//   ^
+// pkg/front_end/testcases/general/mixin_application_override.dart:8:3: Context: This is the overridden method ('foo').
+//   foo([x]) {}
+//   ^
+//
+// pkg/front_end/testcases/general/mixin_application_override.dart:37:7: Error: Applying the mixin 'M' to 'S with M1' introduces an erroneous override of 'foo'.
+// class B1X extends S with M1, M, MX {}
+//       ^^^
+// pkg/front_end/testcases/general/mixin_application_override.dart:12:3: Context: The method 'M.foo' has fewer positional arguments than those of overridden method 'S.foo'.
+//   foo() {}
+//   ^
+// pkg/front_end/testcases/general/mixin_application_override.dart:8:3: Context: This is the overridden method ('foo').
+//   foo([x]) {}
+//   ^
+//
+// pkg/front_end/testcases/general/mixin_application_override.dart:39:7: Error: Applying the mixin 'M' to 'S with M1, M2' introduces an erroneous override of 'foo'.
+// class B2X extends S with M1, M2, M, MX {}
+//       ^^^
+// pkg/front_end/testcases/general/mixin_application_override.dart:12:3: Context: The method 'M.foo' has fewer positional arguments than those of overridden method 'S.foo'.
+//   foo() {}
+//   ^
+// pkg/front_end/testcases/general/mixin_application_override.dart:8:3: Context: This is the overridden method ('foo').
+//   foo([x]) {}
+//   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class S extends core::Object {
+  synthetic constructor •() → self::S*
+    : super core::Object::•()
+    ;
+  method foo([dynamic x = #C1]) → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M extends core::Object {
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M1 extends core::Object {
+  synthetic constructor •() → self::M1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M2 extends core::Object {
+  synthetic constructor •() → self::M2*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class MX extends core::Object {
+  synthetic constructor •() → self::MX*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A0 = self::S with self::M {
+  synthetic constructor •() → self::A0*
+    : super self::S::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::M::foo}();
+}
+abstract class _A1&S&M1 = self::S with self::M1 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A1&S&M1*
+    : super self::S::•()
+    ;
+}
+class A1 = self::_A1&S&M1 with self::M {
+  synthetic constructor •() → self::A1*
+    : super self::_A1&S&M1::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::M::foo}();
+}
+abstract class _A2&S&M1 = self::S with self::M1 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A2&S&M1*
+    : super self::S::•()
+    ;
+}
+abstract class _A2&S&M1&M2 = self::_A2&S&M1 with self::M2 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A2&S&M1&M2*
+    : super self::_A2&S&M1::•()
+    ;
+}
+class A2 = self::_A2&S&M1&M2 with self::M {
+  synthetic constructor •() → self::A2*
+    : super self::_A2&S&M1&M2::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::M::foo}();
+}
+abstract class _A0X&S&M = self::S with self::M /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A0X&S&M*
+    : super self::S::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::M::foo}();
+}
+class A0X = self::_A0X&S&M with self::MX {
+  synthetic constructor •() → self::A0X*
+    : super self::_A0X&S&M::•()
+    ;
+}
+abstract class _A1X&S&M1 = self::S with self::M1 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A1X&S&M1*
+    : super self::S::•()
+    ;
+}
+abstract class _A1X&S&M1&M = self::_A1X&S&M1 with self::M /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A1X&S&M1&M*
+    : super self::_A1X&S&M1::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::M::foo}();
+}
+class A1X = self::_A1X&S&M1&M with self::MX {
+  synthetic constructor •() → self::A1X*
+    : super self::_A1X&S&M1&M::•()
+    ;
+}
+abstract class _A2X&S&M1 = self::S with self::M1 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A2X&S&M1*
+    : super self::S::•()
+    ;
+}
+abstract class _A2X&S&M1&M2 = self::_A2X&S&M1 with self::M2 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A2X&S&M1&M2*
+    : super self::_A2X&S&M1::•()
+    ;
+}
+abstract class _A2X&S&M1&M2&M = self::_A2X&S&M1&M2 with self::M /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A2X&S&M1&M2&M*
+    : super self::_A2X&S&M1&M2::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::M::foo}();
+}
+class A2X = self::_A2X&S&M1&M2&M with self::MX {
+  synthetic constructor •() → self::A2X*
+    : super self::_A2X&S&M1&M2&M::•()
+    ;
+}
+abstract class _B0&S&M = self::S with self::M /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B0&S&M*
+    : super self::S::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::M::foo}();
+}
+class B0 extends self::_B0&S&M {
+  synthetic constructor •() → self::B0*
+    : super self::_B0&S&M::•()
+    ;
+}
+abstract class _B1&S&M1 = self::S with self::M1 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B1&S&M1*
+    : super self::S::•()
+    ;
+}
+abstract class _B1&S&M1&M = self::_B1&S&M1 with self::M /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B1&S&M1&M*
+    : super self::_B1&S&M1::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::M::foo}();
+}
+class B1 extends self::_B1&S&M1&M {
+  synthetic constructor •() → self::B1*
+    : super self::_B1&S&M1&M::•()
+    ;
+}
+abstract class _B2&S&M1 = self::S with self::M1 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B2&S&M1*
+    : super self::S::•()
+    ;
+}
+abstract class _B2&S&M1&M2 = self::_B2&S&M1 with self::M2 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B2&S&M1&M2*
+    : super self::_B2&S&M1::•()
+    ;
+}
+abstract class _B2&S&M1&M2&M = self::_B2&S&M1&M2 with self::M /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B2&S&M1&M2&M*
+    : super self::_B2&S&M1&M2::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::M::foo}();
+}
+class B2 extends self::_B2&S&M1&M2&M {
+  synthetic constructor •() → self::B2*
+    : super self::_B2&S&M1&M2&M::•()
+    ;
+}
+abstract class _B0X&S&M = self::S with self::M /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B0X&S&M*
+    : super self::S::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::M::foo}();
+}
+abstract class _B0X&S&M&MX = self::_B0X&S&M with self::MX /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B0X&S&M&MX*
+    : super self::_B0X&S&M::•()
+    ;
+}
+class B0X extends self::_B0X&S&M&MX {
+  synthetic constructor •() → self::B0X*
+    : super self::_B0X&S&M&MX::•()
+    ;
+}
+abstract class _B1X&S&M1 = self::S with self::M1 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B1X&S&M1*
+    : super self::S::•()
+    ;
+}
+abstract class _B1X&S&M1&M = self::_B1X&S&M1 with self::M /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B1X&S&M1&M*
+    : super self::_B1X&S&M1::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::M::foo}();
+}
+abstract class _B1X&S&M1&M&MX = self::_B1X&S&M1&M with self::MX /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B1X&S&M1&M&MX*
+    : super self::_B1X&S&M1&M::•()
+    ;
+}
+class B1X extends self::_B1X&S&M1&M&MX {
+  synthetic constructor •() → self::B1X*
+    : super self::_B1X&S&M1&M&MX::•()
+    ;
+}
+abstract class _B2X&S&M1 = self::S with self::M1 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B2X&S&M1*
+    : super self::S::•()
+    ;
+}
+abstract class _B2X&S&M1&M2 = self::_B2X&S&M1 with self::M2 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B2X&S&M1&M2*
+    : super self::_B2X&S&M1::•()
+    ;
+}
+abstract class _B2X&S&M1&M2&M = self::_B2X&S&M1&M2 with self::M /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B2X&S&M1&M2&M*
+    : super self::_B2X&S&M1&M2::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::M::foo}();
+}
+abstract class _B2X&S&M1&M2&M&MX = self::_B2X&S&M1&M2&M with self::MX /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B2X&S&M1&M2&M&MX*
+    : super self::_B2X&S&M1&M2&M::•()
+    ;
+}
+class B2X extends self::_B2X&S&M1&M2&M&MX {
+  synthetic constructor •() → self::B2X*
+    : super self::_B2X&S&M1&M2&M&MX::•()
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/mixin_conflicts.dart.weak.modular.expect b/pkg/front_end/testcases/general/mixin_conflicts.dart.weak.modular.expect
new file mode 100644
index 0000000..94fa4c4
--- /dev/null
+++ b/pkg/front_end/testcases/general/mixin_conflicts.dart.weak.modular.expect
@@ -0,0 +1,185 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/mixin_conflicts.dart:22:7: Error: The non-abstract class 'N2' is missing implementations for these members:
+//  - M.foo
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class N2 = Object with M2;
+//       ^^
+// pkg/front_end/testcases/general/mixin_conflicts.dart:7:3: Context: 'M.foo' is defined here.
+//   foo() {}
+//   ^^^
+//
+// pkg/front_end/testcases/general/mixin_conflicts.dart:29:7: Error: The non-abstract class 'C2' is missing implementations for these members:
+//  - M.foo
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class C2 extends Object with M2 {}
+//       ^^
+// pkg/front_end/testcases/general/mixin_conflicts.dart:7:3: Context: 'M.foo' is defined here.
+//   foo() {}
+//   ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class M extends core::Object {
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class N = core::Object with self::M /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::N*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::M::foo}();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&Object&N = core::Object with self::N /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&N*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::M::foo}();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::_C&Object&N {
+  synthetic constructor •() → self::C*
+    : super self::_C&Object&N::•()
+    ;
+}
+abstract class M2 extends core::Object implements self::M {
+  synthetic constructor •() → self::M2*
+    : super core::Object::•()
+    ;
+  method bar() → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class N2 = core::Object with self::M2 /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::N2*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method bar() → dynamic
+    return super.{self::M2::bar}();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class N3 = core::Object with self::M2 /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::N3*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method bar() → dynamic
+    return super.{self::M2::bar}();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C2&Object&M2 = core::Object with self::M2 /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C2&Object&M2*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method bar() → dynamic
+    return super.{self::M2::bar}();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C2 extends self::_C2&Object&M2 {
+  synthetic constructor •() → self::C2*
+    : super self::_C2&Object&M2::•()
+    ;
+}
+abstract class _C3&Object&M2 = core::Object with self::M2 /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C3&Object&M2*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method bar() → dynamic
+    return super.{self::M2::bar}();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C3 extends self::_C3&Object&M2 {
+  synthetic constructor •() → self::C3*
+    : super self::_C3&Object&M2::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart.weak.expect b/pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart.weak.expect
index eba1d44..813bde3 100644
--- a/pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart.weak.expect
+++ b/pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart.weak.expect
@@ -2,7 +2,7 @@
 //
 // Problems in library:
 //
-// pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart:9:15: Error: Type variables can't be used as constants.
+// pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart:9:15: Error: Type variables can't be used in static members.
 //   C({a: 0, b: T}) : trace = "a: $a, b: $b";
 //               ^
 //
@@ -14,7 +14,7 @@
 
 class C<T extends core::Object* = dynamic> extends core::Object {
   field core::String* trace;
-  constructor •({dynamic a = #C1, dynamic b = invalid-expression "Type variables can't be used as constants."}) → self::C<self::C::T*>*
+  constructor •({dynamic a = #C1, dynamic b = #C2}) → self::C<self::C::T*>*
     : self::C::trace = "a: ${a}, b: ${b}", super core::Object::•()
     ;
   abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
@@ -54,7 +54,7 @@
     ;
 }
 abstract class _F&C&M = self::C<core::int*> with self::M /*isAnonymousMixin*/  {
-  synthetic constructor •({dynamic a = #C1, dynamic b = #C3}) → self::_F&C&M*
+  synthetic constructor •({dynamic a = #C1, dynamic b = #C2}) → self::_F&C&M*
     : super self::C::•(a: a, b: b)
     ;
 }
@@ -73,6 +73,5 @@
 
 constants  {
   #C1 = 0
-  #C2 = TypeLiteralConstant(core::String*)
-  #C3 = TypeLiteralConstant(core::int*)
+  #C2 = TypeLiteralConstant(invalid-type)
 }
diff --git a/pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart.weak.modular.expect b/pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart.weak.modular.expect
new file mode 100644
index 0000000..813bde3
--- /dev/null
+++ b/pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart.weak.modular.expect
@@ -0,0 +1,77 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart:9:15: Error: Type variables can't be used in static members.
+//   C({a: 0, b: T}) : trace = "a: $a, b: $b";
+//               ^
+//
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  field core::String* trace;
+  constructor •({dynamic a = #C1, dynamic b = #C2}) → self::C<self::C::T*>*
+    : self::C::trace = "a: ${a}, b: ${b}", super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M extends core::Object {
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D = self::C<core::String*> with self::M {
+  synthetic constructor •({dynamic a = #C1, dynamic b = #C2}) → self::D*
+    : super self::C::•(a: a, b: b)
+    ;
+}
+class E extends self::D {
+  synthetic constructor •() → self::E*
+    : super self::D::•()
+    ;
+}
+abstract class _F&C&M = self::C<core::int*> with self::M /*isAnonymousMixin*/  {
+  synthetic constructor •({dynamic a = #C1, dynamic b = #C2}) → self::_F&C&M*
+    : super self::C::•(a: a, b: b)
+    ;
+}
+class F extends self::_F&C&M {
+  synthetic constructor •() → self::F*
+    : super self::_F&C&M::•()
+    ;
+}
+static method main() → dynamic {
+  exp::Expect::stringEquals("a: 0, b: T", new self::C::•<core::Object*>().{self::C::trace}{core::String*});
+  exp::Expect::stringEquals("a: 0, b: T", new self::C::•<dynamic>().{self::C::trace}{core::String*});
+  exp::Expect::stringEquals("a: 0, b: String", new self::D::•().{self::C::trace}{core::String*});
+  exp::Expect::stringEquals("a: 0, b: String", new self::E::•().{self::C::trace}{core::String*});
+  exp::Expect::stringEquals("a: 0, b: int", new self::F::•().{self::C::trace}{core::String*});
+}
+
+constants  {
+  #C1 = 0
+  #C2 = TypeLiteralConstant(invalid-type)
+}
diff --git a/pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart.weak.outline.expect b/pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart.weak.outline.expect
index 1b5d000..b84923c 100644
--- a/pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart.weak.outline.expect
@@ -1,4 +1,11 @@
 library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart:9:15: Error: Type variables can't be used in static members.
+//   C({a: 0, b: T}) : trace = "a: $a, b: $b";
+//               ^
+//
 import self as self;
 import "dart:core" as core;
 
@@ -6,7 +13,7 @@
 
 class C<T extends core::Object* = dynamic> extends core::Object {
   field core::String* trace;
-  constructor •({dynamic a, dynamic b}) → self::C<self::C::T*>*
+  constructor •({dynamic a = 0, dynamic b = invalid-type}) → self::C<self::C::T*>*
     ;
   abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
   abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
@@ -53,3 +60,8 @@
 }
 static method main() → dynamic
   ;
+
+
+Extra constant evaluation status:
+Evaluated: TypeLiteral @ org-dartlang-testcase:///mixin_constructors_with_default_values.dart:9:15 -> TypeLiteralConstant(<invalid>)
+Extra constant evaluation: evaluated: 5, effectively constant: 1
diff --git a/pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart.weak.transformed.expect b/pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart.weak.transformed.expect
index 7780786..ee8735c 100644
--- a/pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart.weak.transformed.expect
@@ -2,7 +2,7 @@
 //
 // Problems in library:
 //
-// pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart:9:15: Error: Type variables can't be used as constants.
+// pkg/front_end/testcases/general/mixin_constructors_with_default_values.dart:9:15: Error: Type variables can't be used in static members.
 //   C({a: 0, b: T}) : trace = "a: $a, b: $b";
 //               ^
 //
@@ -14,7 +14,7 @@
 
 class C<T extends core::Object* = dynamic> extends core::Object {
   field core::String* trace;
-  constructor •({dynamic a = #C1, dynamic b = invalid-expression "Type variables can't be used as constants."}) → self::C<self::C::T*>*
+  constructor •({dynamic a = #C1, dynamic b = #C2}) → self::C<self::C::T*>*
     : self::C::trace = "a: ${a}, b: ${b}", super core::Object::•()
     ;
   abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
@@ -54,7 +54,7 @@
     ;
 }
 abstract class _F&C&M extends self::C<core::int*> implements self::M /*isAnonymousMixin,isEliminatedMixin*/  {
-  synthetic constructor •({dynamic a = #C1, dynamic b = #C3}) → self::_F&C&M*
+  synthetic constructor •({dynamic a = #C1, dynamic b = #C2}) → self::_F&C&M*
     : super self::C::•(a: a, b: b)
     ;
 }
@@ -73,6 +73,5 @@
 
 constants  {
   #C1 = 0
-  #C2 = TypeLiteralConstant(core::String*)
-  #C3 = TypeLiteralConstant(core::int*)
+  #C2 = TypeLiteralConstant(invalid-type)
 }
diff --git a/pkg/front_end/testcases/general/mixin_covariant.dart.weak.modular.expect b/pkg/front_end/testcases/general/mixin_covariant.dart.weak.modular.expect
new file mode 100644
index 0000000..503a71e
--- /dev/null
+++ b/pkg/front_end/testcases/general/mixin_covariant.dart.weak.modular.expect
@@ -0,0 +1,359 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef TakeInts = (core::int*, core::int*, core::int*, core::int*, core::int*) →* void;
+typedef TakeObjectsAndInts = (core::Object*, core::int*, core::Object*, core::int*, core::int*) →* void;
+typedef TakeObjects = (core::Object*, core::Object*, core::Object*, core::Object*, core::Object*) →* void;
+typedef TakeOptionalInts = ([core::int*, core::int*, core::int*, core::int*]) →* void;
+typedef TakeOptionalObjectsAndInts = ([core::Object*, core::int*, core::Object*, core::int*]) →* void;
+typedef TakeNamedInts = ({a: core::int*, b: core::int*, c: core::int*, d: core::int*}) →* void;
+typedef TakeNamedObjectsAndInts = ({a: core::Object*, b: core::int*, c: core::Object*, d: core::int*}) →* void;
+class M1 extends core::Object {
+  synthetic constructor •() → self::M1*
+    : super core::Object::•()
+    ;
+  method method(covariant-by-declaration core::int* a, core::int* b) → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M2 extends core::Object {
+  synthetic constructor •() → self::M2*
+    : super core::Object::•()
+    ;
+  method method(core::int* a, covariant-by-declaration core::int* b) → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&Object&M1 = core::Object with self::M1 /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&M1*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(covariant-by-declaration core::int* a, core::int* b) → dynamic
+    return super.{self::M1::method}(a, b);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&Object&M1&M2 = self::_C&Object&M1 with self::M2 /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&M1&M2*
+    : super self::_C&Object&M1::•()
+    ;
+  forwarding-stub method method(covariant-by-declaration core::int* a, covariant-by-declaration core::int* b) → dynamic
+    return super.{self::M2::method}(a, b);
+}
+class C extends self::_C&Object&M1&M2 {
+  synthetic constructor •() → self::C*
+    : super self::_C&Object&M1&M2::•()
+    ;
+}
+class Direct extends core::Object {
+  synthetic constructor •() → self::Direct*
+    : super core::Object::•()
+    ;
+  method positional(covariant-by-declaration core::int* a, core::int* b, covariant-by-declaration core::int* c, core::int* d, core::int* e) → void {}
+  method optional([covariant-by-declaration core::int* a = #C1, core::int* b = #C1, covariant-by-declaration core::int* c = #C1, core::int* d = #C1]) → void {}
+  method named({covariant-by-declaration core::int* a = #C1, core::int* b = #C1, covariant-by-declaration core::int* c = #C1, core::int* d = #C1}) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Inherited extends self::Direct {
+  synthetic constructor •() → self::Inherited*
+    : super self::Direct::•()
+    ;
+}
+class Override1 extends core::Object {
+  synthetic constructor •() → self::Override1*
+    : super core::Object::•()
+    ;
+  method method(covariant-by-declaration core::int* a, core::int* b, core::int* c, core::int* d, core::int* e) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Override2 extends self::Override1 {
+  synthetic constructor •() → self::Override2*
+    : super self::Override1::•()
+    ;
+  method method(covariant-by-declaration core::int* a, core::int* b, covariant-by-declaration core::int* c, core::int* d, core::int* e) → void {}
+}
+class Override3 extends self::Override2 {
+  synthetic constructor •() → self::Override3*
+    : super self::Override2::•()
+    ;
+  method method(covariant-by-declaration core::int* a, core::int* b, covariant-by-declaration core::int* c, core::int* d, core::int* e) → void {}
+}
+abstract class Implement1 extends core::Object {
+  synthetic constructor •() → self::Implement1*
+    : super core::Object::•()
+    ;
+  method method(covariant-by-declaration core::int* a, core::int* b, core::int* c, core::int* d, core::int* e) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Implement2 extends core::Object {
+  synthetic constructor •() → self::Implement2*
+    : super core::Object::•()
+    ;
+  method method(core::int* a, covariant-by-declaration core::int* b, core::int* c, core::int* d, core::int* e) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Implement3 extends core::Object {
+  synthetic constructor •() → self::Implement3*
+    : super core::Object::•()
+    ;
+  method method(core::int* a, core::int* b, covariant-by-declaration core::int* c, core::int* d, core::int* e) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Implement4 extends core::Object implements self::Implement3 {
+  synthetic constructor •() → self::Implement4*
+    : super core::Object::•()
+    ;
+  method method(core::int* a, core::int* b, covariant-by-declaration core::int* c, covariant-by-declaration core::int* d, core::int* e) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Implement5 extends core::Object implements self::Implement1, self::Implement2, self::Implement4 {
+  synthetic constructor •() → self::Implement5*
+    : super core::Object::•()
+    ;
+  method method(covariant-by-declaration core::int* a, covariant-by-declaration core::int* b, covariant-by-declaration core::int* c, covariant-by-declaration core::int* d, covariant-by-declaration core::int* e) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Interface1 extends core::Object {
+  synthetic constructor •() → self::Interface1*
+    : super core::Object::•()
+    ;
+  method method(covariant-by-declaration core::int* a, core::int* b, core::int* c, core::int* d, core::int* e) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Interface2 extends core::Object {
+  synthetic constructor •() → self::Interface2*
+    : super core::Object::•()
+    ;
+  method method(core::int* a, covariant-by-declaration core::int* b, core::int* c, core::int* d, core::int* e) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Mixin1 extends core::Object {
+  synthetic constructor •() → self::Mixin1*
+    : super core::Object::•()
+    ;
+  method method(core::int* a, core::int* b, covariant-by-declaration core::int* c, core::int* d, core::int* e) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Mixin2 extends core::Object {
+  synthetic constructor •() → self::Mixin2*
+    : super core::Object::•()
+    ;
+  method method(core::int* a, core::int* b, core::int* c, covariant-by-declaration core::int* d, core::int* e) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Superclass extends core::Object {
+  synthetic constructor •() → self::Superclass*
+    : super core::Object::•()
+    ;
+  method method(core::int* a, core::int* b, core::int* c, core::int* d, covariant-by-declaration core::int* e) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Mixed&Superclass&Mixin1 = self::Superclass with self::Mixin1 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Mixed&Superclass&Mixin1*
+    : super self::Superclass::•()
+    ;
+  forwarding-stub method method(core::int* a, core::int* b, covariant-by-declaration core::int* c, core::int* d, covariant-by-declaration core::int* e) → void
+    return super.{self::Mixin1::method}(a, b, c, d, e);
+}
+abstract class _Mixed&Superclass&Mixin1&Mixin2 = self::_Mixed&Superclass&Mixin1 with self::Mixin2 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Mixed&Superclass&Mixin1&Mixin2*
+    : super self::_Mixed&Superclass&Mixin1::•()
+    ;
+  forwarding-stub method method(core::int* a, core::int* b, covariant-by-declaration core::int* c, covariant-by-declaration core::int* d, covariant-by-declaration core::int* e) → void
+    return super.{self::Mixin2::method}(a, b, c, d, e);
+}
+class Mixed extends self::_Mixed&Superclass&Mixin1&Mixin2 implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::Mixed*
+    : super self::_Mixed&Superclass&Mixin1&Mixin2::•()
+    ;
+  forwarding-stub method method(covariant-by-declaration core::int* a, covariant-by-declaration core::int* b, covariant-by-declaration core::int* c, covariant-by-declaration core::int* d, covariant-by-declaration core::int* e) → void
+    return super.{self::Mixin2::method}(a, b, c, d, e);
+}
+static method main() → void {
+  self::testDirect();
+  self::testInherited();
+  self::testOverridden();
+  self::testImplemented();
+  self::testMixed();
+}
+static method testDirect() → void {
+  (core::int*, core::int*, core::int*, core::int*, core::int*) →* void positional = new self::Direct::•().{self::Direct::positional}{(core::int*, core::int*, core::int*, core::int*, core::int*) →* void};
+  self::isTrue(positional is (core::int*, core::int*, core::int*, core::int*, core::int*) →* void);
+  self::isTrue(positional is (core::Object*, core::int*, core::Object*, core::int*, core::int*) →* void);
+  ([core::int*, core::int*, core::int*, core::int*]) →* void optional = new self::Direct::•().{self::Direct::optional}{([core::int*, core::int*, core::int*, core::int*]) →* void};
+  self::isTrue(optional is ([core::int*, core::int*, core::int*, core::int*]) →* void);
+  self::isTrue(optional is ([core::Object*, core::int*, core::Object*, core::int*]) →* void);
+  ({a: core::int*, b: core::int*, c: core::int*, d: core::int*}) →* void named = new self::Direct::•().{self::Direct::named}{({a: core::int*, b: core::int*, c: core::int*, d: core::int*}) →* void};
+  self::isTrue(named is ({a: core::int*, b: core::int*, c: core::int*, d: core::int*}) →* void);
+  self::isTrue(named is ({a: core::Object*, b: core::int*, c: core::Object*, d: core::int*}) →* void);
+}
+static method testInherited() → void {
+  (core::int*, core::int*, core::int*, core::int*, core::int*) →* void positional = new self::Inherited::•().{self::Direct::positional}{(core::int*, core::int*, core::int*, core::int*, core::int*) →* void};
+  self::isTrue(positional is (core::int*, core::int*, core::int*, core::int*, core::int*) →* void);
+  self::isTrue(positional is (core::Object*, core::int*, core::Object*, core::int*, core::int*) →* void);
+  ([core::int*, core::int*, core::int*, core::int*]) →* void optional = new self::Inherited::•().{self::Direct::optional}{([core::int*, core::int*, core::int*, core::int*]) →* void};
+  self::isTrue(optional is ([core::int*, core::int*, core::int*, core::int*]) →* void);
+  self::isTrue(optional is ([core::Object*, core::int*, core::Object*, core::int*]) →* void);
+  ({a: core::int*, b: core::int*, c: core::int*, d: core::int*}) →* void named = new self::Inherited::•().{self::Direct::named}{({a: core::int*, b: core::int*, c: core::int*, d: core::int*}) →* void};
+  self::isTrue(named is ({a: core::int*, b: core::int*, c: core::int*, d: core::int*}) →* void);
+  self::isTrue(named is ({a: core::Object*, b: core::int*, c: core::Object*, d: core::int*}) →* void);
+}
+static method testOverridden() → void {
+  (core::int*, core::int*, core::int*, core::int*, core::int*) →* void method2 = new self::Override2::•().{self::Override2::method}{(core::int*, core::int*, core::int*, core::int*, core::int*) →* void};
+  self::isTrue(method2 is (core::int*, core::int*, core::int*, core::int*, core::int*) →* void);
+  self::isTrue(method2 is (core::Object*, core::int*, core::Object*, core::int*, core::int*) →* void);
+  (core::int*, core::int*, core::int*, core::int*, core::int*) →* void method3 = new self::Override3::•().{self::Override3::method}{(core::int*, core::int*, core::int*, core::int*, core::int*) →* void};
+  self::isTrue(method3 is (core::int*, core::int*, core::int*, core::int*, core::int*) →* void);
+  self::isTrue(method3 is (core::Object*, core::int*, core::Object*, core::int*, core::int*) →* void);
+}
+static method testImplemented() → void {
+  (core::int*, core::int*, core::int*, core::int*, core::int*) →* void method = new self::Implement5::•().{self::Implement5::method}{(core::int*, core::int*, core::int*, core::int*, core::int*) →* void};
+  self::isTrue(method is (core::int*, core::int*, core::int*, core::int*, core::int*) →* void);
+  self::isTrue(method is (core::Object*, core::Object*, core::Object*, core::Object*, core::Object*) →* void);
+}
+static method testMixed() → void {
+  (core::int*, core::int*, core::int*, core::int*, core::int*) →* void method = new self::Mixed::•().{self::Mixed::method}{(core::int*, core::int*, core::int*, core::int*, core::int*) →* void};
+  self::isTrue(method is (core::int*, core::int*, core::int*, core::int*, core::int*) →* void);
+  self::isTrue(method is (core::Object*, core::Object*, core::Object*, core::Object*, core::Object*) →* void);
+}
+static method isTrue(core::bool* value) → void {
+  if(!value)
+    throw "Expected true";
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/mixin_covariant2.dart.weak.modular.expect b/pkg/front_end/testcases/general/mixin_covariant2.dart.weak.modular.expect
new file mode 100644
index 0000000..8a65e36
--- /dev/null
+++ b/pkg/front_end/testcases/general/mixin_covariant2.dart.weak.modular.expect
@@ -0,0 +1,99 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Superclass extends core::Object {
+  synthetic constructor •() → self::Superclass*
+    : super core::Object::•()
+    ;
+  method method1(core::num* argument1, core::num* argument2) → core::String*
+    return "Superclass";
+  method method2(core::num* argument1, core::num* argument2) → core::String*
+    return "Superclass";
+  method method3(core::num* argument1, covariant-by-declaration core::int* argument2) → core::String*
+    return "Superclass";
+  method method4(core::num* argument1, covariant-by-declaration core::num* argument2) → core::String*
+    return "Superclass";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Mixin extends core::Object {
+  synthetic constructor •() → self::Mixin*
+    : super core::Object::•()
+    ;
+  method method1(core::num* argument1, core::num* argument2) → core::String*
+    return "Mixin";
+  method method2(covariant-by-declaration core::int* argument1, core::num* argument2) → core::String*
+    return "Mixin";
+  method method3(core::num* argument1, core::num* argument2) → core::String*
+    return "Mixin";
+  method method4(covariant-by-declaration core::int* argument1, core::int* argument2) → core::String*
+    return "Mixin";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Class&Superclass&Mixin = self::Superclass with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Superclass&Mixin*
+    : super self::Superclass::•()
+    ;
+  mixin-super-stub method method1(core::num* argument1, core::num* argument2) → core::String*
+    return super.{self::Mixin::method1}(argument1, argument2);
+  mixin-super-stub method method2(covariant-by-declaration core::int* argument1, core::num* argument2) → core::String*
+    return super.{self::Mixin::method2}(argument1, argument2);
+  forwarding-stub method method3(core::num* argument1, covariant-by-declaration core::num* argument2) → core::String*
+    return super.{self::Mixin::method3}(argument1, argument2);
+  forwarding-stub method method4(covariant-by-declaration core::int* argument1, covariant-by-declaration core::int* argument2) → core::String*
+    return super.{self::Mixin::method4}(argument1, argument2);
+}
+class Class extends self::_Class&Superclass&Mixin {
+  synthetic constructor •() → self::Class*
+    : super self::_Class&Superclass&Mixin::•()
+    ;
+}
+static method main() → dynamic {
+  self::Class* c = new self::Class::•();
+  self::expect("Mixin", c.{self::_Class&Superclass&Mixin::method1}(0, 1){(core::num*, core::num*) →* core::String*});
+  self::expect("Mixin", c.{self::_Class&Superclass&Mixin::method2}(0, 1){(core::int*, core::num*) →* core::String*});
+  self::expect("Mixin", c.{self::_Class&Superclass&Mixin::method3}(0, 1){(core::num*, core::num*) →* core::String*});
+  self::expect("Mixin", c.{self::_Class&Superclass&Mixin::method4}(0, 1){(core::int*, core::int*) →* core::String*});
+  self::Superclass* s = c;
+  self::expect("Mixin", s.{self::Superclass::method1}(0.5, 1.5){(core::num*, core::num*) →* core::String*});
+  self::throws(() → core::String* => s.{self::Superclass::method2}(0.5, 1.5){(core::num*, core::num*) →* core::String*});
+  self::expect("Mixin", s.{self::Superclass::method3}(0.5, 1){(core::num*, core::int*) →* core::String*});
+  self::throws(() → core::String* => s.{self::Superclass::method4}(0.5, 1){(core::num*, core::num*) →* core::String*});
+  self::expect("Mixin", s.{self::Superclass::method4}(1, 0.5){(core::num*, core::num*) →* core::String*});
+  self::Mixin* m = c;
+  self::expect("Mixin", m.{self::Mixin::method1}(0, 1){(core::num*, core::num*) →* core::String*});
+  self::expect("Mixin", m.{self::Mixin::method2}(0, 1){(core::int*, core::num*) →* core::String*});
+  self::expect("Mixin", m.{self::Mixin::method3}(0, 1){(core::num*, core::num*) →* core::String*});
+  self::expect("Mixin", m.{self::Mixin::method4}(0, 1){(core::int*, core::int*) →* core::String*});
+}
+static method expect(dynamic expected, dynamic actual) → void {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() →* void f) → void {
+  try {
+    f(){() →* void};
+  }
+  on dynamic catch(final dynamic _) {
+    return;
+  }
+  throw "Expected exception";
+}
diff --git a/pkg/front_end/testcases/general/mixin_from_patch/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/mixin_from_patch/main.dart.weak.modular.expect
new file mode 100644
index 0000000..964cf88
--- /dev/null
+++ b/pkg/front_end/testcases/general/mixin_from_patch/main.dart.weak.modular.expect
@@ -0,0 +1,91 @@
+library;
+import self as self;
+import "dart:test" as test;
+
+import "dart:test";
+
+static method main() → dynamic {
+  new test::Class::patched();
+  new test::Class::unpatched();
+  new test::SubClass::patched();
+  new test::SubClass::unpatched();
+}
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/mixin_from_patch/origin_lib.dart:14:12: Error: The superclass, 'Class with Mixin', has no unnamed constructor that takes no arguments.
+//   external SubClass.patched();
+//            ^^^^^^^
+//
+import self as test;
+import "dart:_internal" as _in;
+import "dart:core" as core;
+
+import "dart:_internal";
+
+@#C1
+class Class extends core::Object {
+  constructor _internal({core::bool* value = #C2}) → test::Class*
+    : super core::Object::•()
+    ;
+  @#C1
+  constructor patched() → test::Class*
+    : this test::Class::_internal()
+    ;
+  constructor unpatched() → test::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _SubClass&Class&Mixin = test::Class with test::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor patched() → test::_SubClass&Class&Mixin*
+    : super test::Class::patched()
+    ;
+  synthetic constructor unpatched() → test::_SubClass&Class&Mixin*
+    : super test::Class::unpatched()
+    ;
+  synthetic constructor _internal({core::bool* value = #C2}) → test::_SubClass&Class&Mixin*
+    : super test::Class::_internal(value: value)
+    ;
+}
+@#C1
+class SubClass extends test::_SubClass&Class&Mixin {
+  constructor _internal() → test::SubClass*
+    : super test::_SubClass&Class&Mixin::_internal(value: true)
+    ;
+  @#C1
+  constructor patched() → test::SubClass*
+    : this test::SubClass::_internal()
+    ;
+  constructor unpatched() → test::SubClass*
+    : super test::_SubClass&Class&Mixin::unpatched()
+    ;
+}
+
+constants  {
+  #C1 = _in::_Patch {}
+  #C2 = false
+}
diff --git a/pkg/front_end/testcases/general/mixin_from_patch/main.dart.weak.outline.expect b/pkg/front_end/testcases/general/mixin_from_patch/main.dart.weak.outline.expect
index 03b90d2..46d5dff 100644
--- a/pkg/front_end/testcases/general/mixin_from_patch/main.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/general/mixin_from_patch/main.dart.weak.outline.expect
@@ -15,7 +15,7 @@
 
 @_in::patch
 class Class extends core::Object {
-  constructor _internal({core::bool* value}) → self2::Class*
+  constructor _internal({core::bool* value = false}) → self2::Class*
     ;
   @_in::patch
   external constructor patched() → self2::Class*
diff --git a/pkg/front_end/testcases/general/mixin_inherited_setter_for_mixed_in_field.dart.weak.modular.expect b/pkg/front_end/testcases/general/mixin_inherited_setter_for_mixed_in_field.dart.weak.modular.expect
new file mode 100644
index 0000000..df2967e
--- /dev/null
+++ b/pkg/front_end/testcases/general/mixin_inherited_setter_for_mixed_in_field.dart.weak.modular.expect
@@ -0,0 +1,78 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<T extends self::A*> extends core::Object {
+  covariant-by-class field self::C::T* _field = null;
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method foo(covariant-by-class self::C::T* x) → dynamic {
+    this.{self::C::_field} = x;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C<self::B*> {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+}
+abstract class _Foo&Object&C = core::Object with self::C<self::B*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Foo&Object&C*
+    : super core::Object::•()
+    ;
+  mixin-super-stub get _field() → self::B*
+    return super.{self::C::_field};
+  mixin-super-stub set _field(covariant-by-class self::B* value) → void
+    return super.{self::C::_field} = value;
+  mixin-super-stub method foo(covariant-by-class self::B* x) → dynamic
+    return super.{self::C::foo}(x);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Foo extends self::_Foo&Object&C {
+  synthetic constructor •() → self::Foo*
+    : super self::_Foo&Object&C::•()
+    ;
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+static method main() → dynamic {
+  self::Foo* foo = new self::Foo::•();
+  foo.{self::_Foo&Object&C::foo}(new self::B::•()){(self::B*) →* dynamic};
+}
diff --git a/pkg/front_end/testcases/general/mixin_interface_conflict.dart.weak.modular.expect b/pkg/front_end/testcases/general/mixin_interface_conflict.dart.weak.modular.expect
new file mode 100644
index 0000000..194538f
--- /dev/null
+++ b/pkg/front_end/testcases/general/mixin_interface_conflict.dart.weak.modular.expect
@@ -0,0 +1,70 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/mixin_interface_conflict.dart:13:7: Error: Class 'B with C' inherits multiple members named 'n' with incompatible signatures.
+// Try adding a declaration of 'n' to 'B with C'.
+// mixin M on B, C {}
+//       ^^^^^^
+// pkg/front_end/testcases/general/mixin_interface_conflict.dart:6:11: Context: This is one of the overridden members.
+//   int get n => 1;
+//           ^
+// pkg/front_end/testcases/general/mixin_interface_conflict.dart:10:14: Context: This is one of the overridden members.
+//   double get n => 2.0;
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  get n() → core::int*
+    return 1;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  get n() → core::double*
+    return 2.0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _M&B&C extends core::Object implements self::B, self::C /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_M&B&C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M extends self::_M&B&C /*isMixinDeclaration*/  {
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/mixin_stubs.dart.weak.modular.expect b/pkg/front_end/testcases/general/mixin_stubs.dart.weak.modular.expect
new file mode 100644
index 0000000..32aae43
--- /dev/null
+++ b/pkg/front_end/testcases/general/mixin_stubs.dart.weak.modular.expect
@@ -0,0 +1,197 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class Super extends core::Object {
+  synthetic constructor •() → self::Super*
+    : super core::Object::•()
+    ;
+  method concreteExtendsConcreteMixin() → void {}
+  method concreteExtendsAbstractMixin() → void {}
+  abstract method abstractExtendsConcreteMixin() → void;
+  abstract method abstractExtendsAbstractMixin() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class MixinClass extends core::Object {
+  synthetic constructor •() → self::MixinClass*
+    : super core::Object::•()
+    ;
+  method concreteExtendsConcreteMixin() → void {}
+  abstract method concreteExtendsAbstractMixin() → void;
+  method concreteMixin() → void {}
+  method abstractExtendsConcreteMixin() → void {}
+  abstract method abstractExtendsAbstractMixin() → void;
+  abstract method abstractMixin() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+  method concreteExtendsConcreteMixin() → void {}
+  abstract method concreteExtendsAbstractMixin() → void;
+  method concreteMixin() → void {}
+  method abstractExtendsConcreteMixin() → void {}
+  abstract method abstractExtendsAbstractMixin() → void;
+  abstract method abstractMixin() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class ClassEqMixinClass = self::Super with self::MixinClass {
+  synthetic constructor •() → self::ClassEqMixinClass*
+    : super self::Super::•()
+    ;
+  mixin-super-stub method concreteExtendsConcreteMixin() → void
+    return super.{self::MixinClass::concreteExtendsConcreteMixin}();
+  abstract mixin-stub method concreteExtendsAbstractMixin() → void; -> self::MixinClass::concreteExtendsAbstractMixin
+  mixin-super-stub method concreteMixin() → void
+    return super.{self::MixinClass::concreteMixin}();
+  mixin-super-stub method abstractExtendsConcreteMixin() → void
+    return super.{self::MixinClass::abstractExtendsConcreteMixin}();
+  abstract mixin-stub method abstractExtendsAbstractMixin() → void; -> self::MixinClass::abstractExtendsAbstractMixin
+  abstract mixin-stub method abstractMixin() → void; -> self::MixinClass::abstractMixin
+}
+abstract class _ClassExtendsMixinClass&Super&MixinClass = self::Super with self::MixinClass /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_ClassExtendsMixinClass&Super&MixinClass*
+    : super self::Super::•()
+    ;
+  mixin-super-stub method concreteExtendsConcreteMixin() → void
+    return super.{self::MixinClass::concreteExtendsConcreteMixin}();
+  abstract mixin-stub method concreteExtendsAbstractMixin() → void; -> self::MixinClass::concreteExtendsAbstractMixin
+  mixin-super-stub method concreteMixin() → void
+    return super.{self::MixinClass::concreteMixin}();
+  mixin-super-stub method abstractExtendsConcreteMixin() → void
+    return super.{self::MixinClass::abstractExtendsConcreteMixin}();
+  abstract mixin-stub method abstractExtendsAbstractMixin() → void; -> self::MixinClass::abstractExtendsAbstractMixin
+  abstract mixin-stub method abstractMixin() → void; -> self::MixinClass::abstractMixin
+}
+abstract class ClassExtendsMixinClass extends self::_ClassExtendsMixinClass&Super&MixinClass {
+  synthetic constructor •() → self::ClassExtendsMixinClass*
+    : super self::_ClassExtendsMixinClass&Super&MixinClass::•()
+    ;
+}
+abstract class ClassEqMixin = self::Super with self::Mixin {
+  synthetic constructor •() → self::ClassEqMixin*
+    : super self::Super::•()
+    ;
+  mixin-super-stub method concreteExtendsConcreteMixin() → void
+    return super.{self::Mixin::concreteExtendsConcreteMixin}();
+  abstract mixin-stub method concreteExtendsAbstractMixin() → void; -> self::Mixin::concreteExtendsAbstractMixin
+  mixin-super-stub method concreteMixin() → void
+    return super.{self::Mixin::concreteMixin}();
+  mixin-super-stub method abstractExtendsConcreteMixin() → void
+    return super.{self::Mixin::abstractExtendsConcreteMixin}();
+  abstract mixin-stub method abstractExtendsAbstractMixin() → void; -> self::Mixin::abstractExtendsAbstractMixin
+  abstract mixin-stub method abstractMixin() → void; -> self::Mixin::abstractMixin
+}
+abstract class _ClassExtendsMixin&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_ClassExtendsMixin&Super&Mixin*
+    : super self::Super::•()
+    ;
+  mixin-super-stub method concreteExtendsConcreteMixin() → void
+    return super.{self::Mixin::concreteExtendsConcreteMixin}();
+  abstract mixin-stub method concreteExtendsAbstractMixin() → void; -> self::Mixin::concreteExtendsAbstractMixin
+  mixin-super-stub method concreteMixin() → void
+    return super.{self::Mixin::concreteMixin}();
+  mixin-super-stub method abstractExtendsConcreteMixin() → void
+    return super.{self::Mixin::abstractExtendsConcreteMixin}();
+  abstract mixin-stub method abstractExtendsAbstractMixin() → void; -> self::Mixin::abstractExtendsAbstractMixin
+  abstract mixin-stub method abstractMixin() → void; -> self::Mixin::abstractMixin
+}
+abstract class ClassExtendsMixin extends self::_ClassExtendsMixin&Super&Mixin {
+  synthetic constructor •() → self::ClassExtendsMixin*
+    : super self::_ClassExtendsMixin&Super&Mixin::•()
+    ;
+}
+abstract class SubclassEqMixinClass extends self::ClassEqMixinClass {
+  synthetic constructor •() → self::SubclassEqMixinClass*
+    : super self::ClassEqMixinClass::•()
+    ;
+  method method() → dynamic {
+    this.{self::ClassEqMixinClass::concreteExtendsConcreteMixin}(){() →* void};
+    this.{self::ClassEqMixinClass::concreteExtendsAbstractMixin}(){() →* void};
+    this.{self::ClassEqMixinClass::concreteMixin}(){() →* void};
+    this.{self::ClassEqMixinClass::abstractExtendsConcreteMixin}(){() →* void};
+    this.{self::ClassEqMixinClass::abstractExtendsAbstractMixin}(){() →* void};
+    this.{self::ClassEqMixinClass::abstractMixin}(){() →* void};
+    super.{self::ClassEqMixinClass::concreteExtendsConcreteMixin}();
+    super.{self::Super::concreteExtendsAbstractMixin}();
+    super.{self::ClassEqMixinClass::concreteMixin}();
+    super.{self::ClassEqMixinClass::abstractExtendsConcreteMixin}();
+  }
+}
+abstract class SubclassExtendsMixinClass extends self::ClassExtendsMixinClass {
+  synthetic constructor •() → self::SubclassExtendsMixinClass*
+    : super self::ClassExtendsMixinClass::•()
+    ;
+  method method() → dynamic {
+    this.{self::_ClassExtendsMixinClass&Super&MixinClass::concreteExtendsConcreteMixin}(){() →* void};
+    this.{self::_ClassExtendsMixinClass&Super&MixinClass::concreteMixin}(){() →* void};
+    this.{self::_ClassExtendsMixinClass&Super&MixinClass::concreteExtendsAbstractMixin}(){() →* void};
+    this.{self::_ClassExtendsMixinClass&Super&MixinClass::abstractExtendsConcreteMixin}(){() →* void};
+    this.{self::_ClassExtendsMixinClass&Super&MixinClass::abstractExtendsAbstractMixin}(){() →* void};
+    this.{self::_ClassExtendsMixinClass&Super&MixinClass::abstractMixin}(){() →* void};
+    super.{self::_ClassExtendsMixinClass&Super&MixinClass::concreteExtendsConcreteMixin}();
+    super.{self::Super::concreteExtendsAbstractMixin}();
+    super.{self::_ClassExtendsMixinClass&Super&MixinClass::concreteMixin}();
+    super.{self::_ClassExtendsMixinClass&Super&MixinClass::abstractExtendsConcreteMixin}();
+  }
+}
+abstract class SubclassEqMixin extends self::ClassEqMixin {
+  synthetic constructor •() → self::SubclassEqMixin*
+    : super self::ClassEqMixin::•()
+    ;
+  method method() → dynamic {
+    this.{self::ClassEqMixin::concreteExtendsConcreteMixin}(){() →* void};
+    this.{self::ClassEqMixin::concreteExtendsAbstractMixin}(){() →* void};
+    this.{self::ClassEqMixin::concreteMixin}(){() →* void};
+    this.{self::ClassEqMixin::abstractExtendsConcreteMixin}(){() →* void};
+    this.{self::ClassEqMixin::abstractExtendsAbstractMixin}(){() →* void};
+    this.{self::ClassEqMixin::abstractMixin}(){() →* void};
+    super.{self::ClassEqMixin::concreteExtendsConcreteMixin}();
+    super.{self::Super::concreteExtendsAbstractMixin}();
+    super.{self::ClassEqMixin::concreteMixin}();
+    super.{self::ClassEqMixin::abstractExtendsConcreteMixin}();
+  }
+}
+abstract class SubclassExtendsMixin extends self::ClassExtendsMixin {
+  synthetic constructor •() → self::SubclassExtendsMixin*
+    : super self::ClassExtendsMixin::•()
+    ;
+  method method() → dynamic {
+    this.{self::_ClassExtendsMixin&Super&Mixin::concreteExtendsConcreteMixin}(){() →* void};
+    this.{self::_ClassExtendsMixin&Super&Mixin::concreteExtendsAbstractMixin}(){() →* void};
+    this.{self::_ClassExtendsMixin&Super&Mixin::concreteMixin}(){() →* void};
+    this.{self::_ClassExtendsMixin&Super&Mixin::abstractExtendsConcreteMixin}(){() →* void};
+    this.{self::_ClassExtendsMixin&Super&Mixin::abstractExtendsAbstractMixin}(){() →* void};
+    this.{self::_ClassExtendsMixin&Super&Mixin::abstractMixin}(){() →* void};
+    super.{self::_ClassExtendsMixin&Super&Mixin::concreteExtendsConcreteMixin}();
+    super.{self::Super::concreteExtendsAbstractMixin}();
+    super.{self::_ClassExtendsMixin&Super&Mixin::concreteMixin}();
+    super.{self::_ClassExtendsMixin&Super&Mixin::abstractExtendsConcreteMixin}();
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/mixin_super_repeated.dart.weak.modular.expect b/pkg/front_end/testcases/general/mixin_super_repeated.dart.weak.modular.expect
new file mode 100644
index 0000000..526ec74
--- /dev/null
+++ b/pkg/front_end/testcases/general/mixin_super_repeated.dart.weak.modular.expect
@@ -0,0 +1,83 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class M extends core::Object {
+  field dynamic m = null;
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class N extends self::M {
+  synthetic constructor •() → self::N*
+    : super self::M::•()
+    ;
+  set superM(dynamic value) → void {
+    super.{self::M::m} = value;
+  }
+  get superM() → dynamic
+    return super.{self::M::m};
+}
+class S extends core::Object {
+  synthetic constructor •() → self::S*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Named&S&M = self::S with self::M /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Named&S&M*
+    : super self::S::•()
+    ;
+  mixin-super-stub get m() → dynamic
+    return super.{self::M::m};
+  mixin-super-stub set m(dynamic value) → void
+    return super.{self::M::m} = value;
+}
+abstract class _Named&S&M&N = self::_Named&S&M with self::N /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Named&S&M&N*
+    : super self::_Named&S&M::•()
+    ;
+  mixin-super-stub get superM() → dynamic
+    return super.{self::N::superM};
+  mixin-super-stub set superM(dynamic value) → void
+    return super.{self::N::superM} = value;
+}
+class Named = self::_Named&S&M&N with self::M {
+  synthetic constructor •() → self::Named*
+    : super self::_Named&S&M&N::•()
+    ;
+  mixin-super-stub get m() → dynamic
+    return super.{self::M::m};
+  mixin-super-stub set m(dynamic value) → void
+    return super.{self::M::m} = value;
+}
+static method main() → dynamic {
+  self::Named* named = new self::Named::•();
+  named.{self::Named::m} = 42;
+  named.{self::_Named&S&M&N::superM} = 87;
+  if(!(named.{self::Named::m}{dynamic} =={core::Object::==}{(core::Object*) →* core::bool*} 42)) {
+    throw "Bad mixin translation of set:superM";
+  }
+  if(!(named.{self::_Named&S&M&N::superM}{dynamic} =={core::Object::==}{(core::Object*) →* core::bool*} 87)) {
+    throw "Bad mixin translation of get:superM";
+  }
+}
diff --git a/pkg/front_end/testcases/general/mixin_with_static_member.dart.weak.modular.expect b/pkg/front_end/testcases/general/mixin_with_static_member.dart.weak.modular.expect
new file mode 100644
index 0000000..e89e537
--- /dev/null
+++ b/pkg/front_end/testcases/general/mixin_with_static_member.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class _A&B&M = self::B with self::M /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A&B&M*
+    : super self::B::•()
+    ;
+}
+class A extends self::_A&B&M {
+  synthetic constructor •() → self::A*
+    : super self::_A&B&M::•()
+    ;
+}
+class B extends core::Object {
+  final field core::Object* m = null;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M extends core::Object {
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  static method m() → core::Object*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::A::•();
+}
diff --git a/pkg/front_end/testcases/general/named_function_scope.dart.weak.modular.expect b/pkg/front_end/testcases/general/named_function_scope.dart.weak.modular.expect
new file mode 100644
index 0000000..8ae3c40
--- /dev/null
+++ b/pkg/front_end/testcases/general/named_function_scope.dart.weak.modular.expect
@@ -0,0 +1,195 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/named_function_scope.dart:26:13: Error: A function expression can't have a name.
+//     var x = T() {};
+//             ^
+//
+// pkg/front_end/testcases/general/named_function_scope.dart:31:9: Error: Can't declare 'V' because it was already used in this scope.
+//     var V;
+//         ^
+// pkg/front_end/testcases/general/named_function_scope.dart:29:5: Context: Previous use of 'V'.
+//     V v;
+//     ^
+//
+// pkg/front_end/testcases/general/named_function_scope.dart:36:9: Error: Can't declare 'V' because it was already used in this scope.
+//     var V = null;
+//         ^
+// pkg/front_end/testcases/general/named_function_scope.dart:34:5: Context: Previous use of 'V'.
+//     V v;
+//     ^
+//
+// pkg/front_end/testcases/general/named_function_scope.dart:41:15: Error: A function expression can't have a name.
+//     var x = T T() {};
+//               ^
+//
+// pkg/front_end/testcases/general/named_function_scope.dart:41:15: Error: Can't declare 'T' because it was already used in this scope.
+//     var x = T T() {};
+//               ^
+// pkg/front_end/testcases/general/named_function_scope.dart:41:13: Context: Previous use of 'T'.
+//     var x = T T() {};
+//             ^
+//
+// pkg/front_end/testcases/general/named_function_scope.dart:47:7: Error: Can't declare 'V' because it was already used in this scope.
+//     V V;
+//       ^
+// pkg/front_end/testcases/general/named_function_scope.dart:47:5: Context: Previous use of 'V'.
+//     V V;
+//     ^
+//
+// pkg/front_end/testcases/general/named_function_scope.dart:52:13: Error: A function expression can't have a name.
+//     var x = T<T>() {};
+//             ^
+//
+// pkg/front_end/testcases/general/named_function_scope.dart:52:13: Error: 'T' is already declared in this scope.
+//     var x = T<T>() {};
+//             ^
+// pkg/front_end/testcases/general/named_function_scope.dart:52:15: Context: Previous declaration of 'T'.
+//     var x = T<T>() {};
+//               ^
+//
+// pkg/front_end/testcases/general/named_function_scope.dart:56:7: Error: Can't declare 'T' because it was already used in this scope.
+//     T T() {}
+//       ^
+// pkg/front_end/testcases/general/named_function_scope.dart:55:5: Context: Previous use of 'T'.
+//     T t;
+//     ^
+//
+// pkg/front_end/testcases/general/named_function_scope.dart:59:7: Error: Can't declare 'T' because it was already used in this scope.
+//     T T() {}
+//       ^
+// pkg/front_end/testcases/general/named_function_scope.dart:59:5: Context: Previous use of 'T'.
+//     T T() {}
+//     ^
+//
+// pkg/front_end/testcases/general/named_function_scope.dart:63:7: Error: Can't declare 'T' because it was already used in this scope.
+//     T T(T t) {}
+//       ^
+// pkg/front_end/testcases/general/named_function_scope.dart:62:5: Context: Previous use of 'T'.
+//     T t;
+//     ^
+//
+// pkg/front_end/testcases/general/named_function_scope.dart:66:7: Error: Can't declare 'T' because it was already used in this scope.
+//     T T(T t) {}
+//       ^
+// pkg/front_end/testcases/general/named_function_scope.dart:66:5: Context: Previous use of 'T'.
+//     T T(T t) {}
+//     ^
+//
+// pkg/front_end/testcases/general/named_function_scope.dart:69:12: Error: 'T' isn't a type.
+//     void T(T t) {}
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class T extends core::Object {
+  synthetic constructor •() → self::T*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class V extends core::Object {
+  synthetic constructor •() → self::V*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  self::T* t;
+  self::V* v;
+  {
+    function T() → Null {}
+  }
+  {
+    dynamic v;
+  }
+  {
+    self::T* t;
+    () →* Null x = let final () →* Null T = () → Null {} in T;
+  }
+  {
+    self::V* v;
+    invalid-type V = invalid-expression "pkg/front_end/testcases/general/named_function_scope.dart:31:9: Error: Can't declare 'V' because it was already used in this scope.
+    var V;
+        ^";
+  }
+  {
+    self::V* v;
+    invalid-type V = invalid-expression "pkg/front_end/testcases/general/named_function_scope.dart:36:9: Error: Can't declare 'V' because it was already used in this scope.
+    var V = null;
+        ^" in null;
+  }
+  {
+    () →* Null x = let final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/named_function_scope.dart:41:15: Error: Can't declare 'T' because it was already used in this scope.
+    var x = T T() {};
+              ^" in let final () →* Null T = () → Null {} in T;
+  }
+  {
+    self::V* V = invalid-expression "pkg/front_end/testcases/general/named_function_scope.dart:47:7: Error: Can't declare 'V' because it was already used in this scope.
+    V V;
+      ^";
+  }
+  {
+    <T extends core::Object* = dynamic>() →* Null x = let final dynamic #t2 = invalid-expression "pkg/front_end/testcases/general/named_function_scope.dart:52:13: Error: 'T' is already declared in this scope.
+    var x = T<T>() {};
+            ^" in let final <T extends core::Object* = dynamic>() →* Null T = <T extends core::Object* = dynamic>() → Null {} in T;
+  }
+  {
+    self::T* t;
+    {
+      invalid-expression "pkg/front_end/testcases/general/named_function_scope.dart:56:7: Error: Can't declare 'T' because it was already used in this scope.
+    T T() {}
+      ^";
+      function T() → self::T* {}
+    }
+  }
+  {
+    {
+      invalid-expression "pkg/front_end/testcases/general/named_function_scope.dart:59:7: Error: Can't declare 'T' because it was already used in this scope.
+    T T() {}
+      ^";
+      function T() → self::T* {}
+    }
+  }
+  {
+    self::T* t;
+    {
+      invalid-expression "pkg/front_end/testcases/general/named_function_scope.dart:63:7: Error: Can't declare 'T' because it was already used in this scope.
+    T T(T t) {}
+      ^";
+      function T(self::T* t) → self::T* {}
+    }
+  }
+  {
+    {
+      invalid-expression "pkg/front_end/testcases/general/named_function_scope.dart:66:7: Error: Can't declare 'T' because it was already used in this scope.
+    T T(T t) {}
+      ^";
+      function T(self::T* t) → self::T* {}
+    }
+  }
+  {
+    function T(invalid-type t) → void {}
+  }
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/general/named_parameters.dart.weak.modular.expect b/pkg/front_end/testcases/general/named_parameters.dart.weak.modular.expect
new file mode 100644
index 0000000..ad0b537
--- /dev/null
+++ b/pkg/front_end/testcases/general/named_parameters.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Superclass extends core::Object {
+  synthetic constructor •() → self::Superclass
+    : super core::Object::•()
+    ;
+  method foo({dynamic alpha = #C1, dynamic beta = #C1}) → dynamic {}
+  method bar({dynamic beta = #C1, dynamic alpha = #C1}) → dynamic {}
+  method namedCallback(({alpha: core::String, beta: core::int}) → dynamic callback) → dynamic {
+    callback(alpha: "one", beta: 2){({alpha: core::String, beta: core::int}) → dynamic};
+    callback(beta: 1, alpha: "two"){({alpha: core::String, beta: core::int}) → dynamic};
+  }
+}
+class Subclass extends self::Superclass {
+  synthetic constructor •() → self::Subclass
+    : super self::Superclass::•()
+    ;
+  method foo({dynamic beta = #C1, dynamic alpha = #C1}) → dynamic {}
+  method bar({dynamic alpha = #C1, dynamic beta = #C1}) → dynamic {}
+  method namedCallback(({alpha: core::String, beta: core::int}) → dynamic callback) → dynamic {}
+}
+static method topLevelNamed(dynamic beta, dynamic alpha, {dynamic gamma = #C1, dynamic delta = #C1}) → dynamic {}
+static method topLevelOptional(dynamic beta, dynamic alpha, [dynamic gamma = #C1, dynamic delta = #C1]) → dynamic {}
+static method main() → dynamic {
+  new self::Subclass::•().{self::Subclass::foo}(beta: 1, alpha: 2){({alpha: dynamic, beta: dynamic}) → dynamic};
+  new self::Subclass::•().{self::Subclass::foo}(alpha: 1, beta: 2){({alpha: dynamic, beta: dynamic}) → dynamic};
+  self::topLevelNamed(1, 2, gamma: 3, delta: 4);
+  self::topLevelNamed(1, 2, delta: 3, gamma: 4);
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/native_as_name.dart.weak.modular.expect b/pkg/front_end/testcases/general/native_as_name.dart.weak.modular.expect
new file mode 100644
index 0000000..f85423d
--- /dev/null
+++ b/pkg/front_end/testcases/general/native_as_name.dart.weak.modular.expect
@@ -0,0 +1,91 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class W extends core::Object {
+  field core::String* native;
+  constructor •() → self::W*
+    : self::W::native = "field", super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class X extends core::Object {
+  synthetic constructor •() → self::X*
+    : super core::Object::•()
+    ;
+  method native() → core::String*
+    return "method";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Y1 extends core::Object {
+  synthetic constructor •() → self::Y1*
+    : super core::Object::•()
+    ;
+  abstract get native() → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Y2 extends self::Y1 {
+  synthetic constructor •() → self::Y2*
+    : super self::Y1::•()
+    ;
+  @#C1
+  get native() → core::String*
+    return "getter";
+}
+class Z extends core::Object {
+  field core::String* f = null;
+  synthetic constructor •() → self::Z*
+    : super core::Object::•()
+    ;
+  set native(core::String* s) → void
+    return this.{self::Z::f} = s;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::print(new self::W::•().{self::W::native}{core::String*});
+  core::print(new self::X::•().{self::X::native}(){() →* core::String*});
+  core::print(new self::Y2::•().{self::Y2::native}{core::String*});
+  core::print((let final self::Z* #t1 = new self::Z::•() in block {
+    #t1.{self::Z::native} = "setter";
+  } =>#t1).{self::Z::f}{core::String*});
+}
+
+constants  {
+  #C1 = core::_Override {}
+}
diff --git a/pkg/front_end/testcases/general/nested_implicit_const_with_env_var.dart.weak.modular.expect b/pkg/front_end/testcases/general/nested_implicit_const_with_env_var.dart.weak.modular.expect
new file mode 100644
index 0000000..ddcf830
--- /dev/null
+++ b/pkg/front_end/testcases/general/nested_implicit_const_with_env_var.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  final field core::int* bar;
+  const constructor •(core::int* bar) → self::A*
+    : self::A::bar = bar, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object /*hasConstConstructor*/  {
+  final field self::A* baz;
+  const constructor •(self::A* baz) → self::B*
+    : self::B::baz = baz, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method fun() → dynamic {
+    new self::B::•(new self::A::•(#C1));
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field core::int* foo = #C1;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+}
diff --git a/pkg/front_end/testcases/general/nested_property_set.dart.weak.modular.expect b/pkg/front_end/testcases/general/nested_property_set.dart.weak.modular.expect
new file mode 100644
index 0000000..692bedb
--- /dev/null
+++ b/pkg/front_end/testcases/general/nested_property_set.dart.weak.modular.expect
@@ -0,0 +1,67 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class NumField extends core::Object {
+  field core::num* field = null;
+  synthetic constructor •() → self::NumField*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class IntField extends core::Object {
+  field core::int* field = null;
+  synthetic constructor •() → self::IntField*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class DoubleField extends core::Object {
+  field core::double* field = null;
+  synthetic constructor •() → self::DoubleField*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::IntField* intField1 = new self::IntField::•();
+  self::IntField* intField2 = new self::IntField::•();
+  self::NumField* numField = new self::NumField::•();
+  self::DoubleField* doubleField = new self::DoubleField::•();
+  intField1.{self::IntField::field} = (intField2.{self::IntField::field} = numField.{self::NumField::field}{core::num*} as{TypeError} core::int*) as{TypeError} core::int*;
+  intField1.{self::IntField::field} = numField.{self::NumField::field} = intField2.{self::IntField::field}{core::int*};
+  try {
+    numField.{self::NumField::field} = 0.5;
+    intField1.{self::IntField::field} = (doubleField.{self::DoubleField::field} = numField.{self::NumField::field}{core::num*} as{TypeError} core::double*) as{TypeError} core::int*;
+    throw "Should fail";
+  }
+  on dynamic catch(final dynamic _) {
+  }
+}
diff --git a/pkg/front_end/testcases/general/nested_variable_set.dart.weak.modular.expect b/pkg/front_end/testcases/general/nested_variable_set.dart.weak.modular.expect
new file mode 100644
index 0000000..7e193c1
--- /dev/null
+++ b/pkg/front_end/testcases/general/nested_variable_set.dart.weak.modular.expect
@@ -0,0 +1,19 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::int* intLocal1;
+  core::int* intLocal2;
+  core::num* numLocal;
+  core::double* doubleLocal;
+  intLocal1 = (intLocal2 = numLocal as{TypeError} core::int*) as{TypeError} core::int*;
+  intLocal1 = numLocal = intLocal2;
+  numLocal = 0.5;
+  try {
+    intLocal1 = (doubleLocal = numLocal as{TypeError} core::double*) as{TypeError} core::int*;
+    throw "Should fail";
+  }
+  on dynamic catch(final dynamic _) {
+  }
+}
diff --git a/pkg/front_end/testcases/general/nested_variance.dart.weak.modular.expect b/pkg/front_end/testcases/general/nested_variance.dart.weak.modular.expect
new file mode 100644
index 0000000..ab01f23
--- /dev/null
+++ b/pkg/front_end/testcases/general/nested_variance.dart.weak.modular.expect
@@ -0,0 +1,301 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef F<invariant X extends core::Object* = dynamic> = <Y extends X* = dynamic>() →* void;
+typedef Fcov<X extends core::Object* = dynamic> = () →* X*;
+typedef Fcon<contravariant X extends core::Object* = dynamic> = (X*) →* dynamic;
+typedef Finv<invariant X extends core::Object* = dynamic> = (X*) →* X*;
+typedef FcovBound<X extends core::num*> = () →* X*;
+typedef FconBound<contravariant X extends core::num*> = (X*) →* dynamic;
+typedef FinvBound<invariant X extends core::num*> = (X*) →* X*;
+typedef FcovCyclicBound<X extends self::A<X*>* = self::A<dynamic>*> = () →* X*;
+typedef FconCyclicBound<contravariant X extends self::A<X*>* = self::A<Null>*> = (X*) →* dynamic;
+typedef FinvCyclicBound<invariant X extends self::A<X*>* = self::A<dynamic>*> = (X*) →* X*;
+typedef FcovCyclicCoBound<X extends (X*) →* dynamic = (Null) →* dynamic> = () →* X*;
+typedef FconCyclicCoBound<contravariant X extends (X*) →* dynamic = (dynamic) →* dynamic> = (X*) →* dynamic;
+typedef FinvCyclicCoBound<invariant X extends (X*) →* dynamic = (dynamic) →* dynamic> = (X*) →* X*;
+class Acov<X extends () →* self::Acov::Y* = () →* dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Acov<self::Acov::X*, self::Acov::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Acon<X extends (self::Acon::Y*) →* dynamic = (Null) →* dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Acon<self::Acon::X*, self::Acon::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Ainv<X extends (self::Ainv::Y*) →* self::Ainv::Y* = (dynamic) →* dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Ainv<self::Ainv::X*, self::Ainv::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class AcovBound<X extends () →* self::AcovBound::Y* = () →* core::num*, Y extends core::num*> extends core::Object {
+  synthetic constructor •() → self::AcovBound<self::AcovBound::X*, self::AcovBound::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class AconBound<X extends (self::AconBound::Y*) →* dynamic = (Null) →* dynamic, Y extends core::num*> extends core::Object {
+  synthetic constructor •() → self::AconBound<self::AconBound::X*, self::AconBound::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class AinvBound<X extends (self::AinvBound::Y*) →* self::AinvBound::Y* = (core::num*) →* core::num*, Y extends core::num*> extends core::Object {
+  synthetic constructor •() → self::AinvBound<self::AinvBound::X*, self::AinvBound::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class AcovCyclicBound<X extends () →* self::AcovCyclicBound::Y* = () →* self::A<dynamic>*, Y extends self::A<self::AcovCyclicBound::Y*>* = self::A<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::AcovCyclicBound<self::AcovCyclicBound::X*, self::AcovCyclicBound::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class AconCyclicBound<X extends (self::AconCyclicBound::Y*) →* dynamic = (Null) →* dynamic, Y extends self::A<self::AconCyclicBound::Y*>* = self::A<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::AconCyclicBound<self::AconCyclicBound::X*, self::AconCyclicBound::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class AinvCyclicBound<X extends (self::AinvCyclicBound::Y*) →* self::AinvCyclicBound::Y* = (self::A<dynamic>*) →* self::A<dynamic>*, Y extends self::A<self::AinvCyclicBound::Y*>* = self::A<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::AinvCyclicBound<self::AinvCyclicBound::X*, self::AinvCyclicBound::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class AcovCyclicCoBound<X extends () →* self::AcovCyclicCoBound::Y* = () →* (Null) →* dynamic, Y extends (self::AcovCyclicCoBound::Y*) →* dynamic = (Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::AcovCyclicCoBound<self::AcovCyclicCoBound::X*, self::AcovCyclicCoBound::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class AconCyclicCoBound<X extends (self::AconCyclicCoBound::Y*) →* dynamic = (Null) →* dynamic, Y extends (self::AconCyclicCoBound::Y*) →* dynamic = (Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::AconCyclicCoBound<self::AconCyclicCoBound::X*, self::AconCyclicCoBound::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class AinvCyclicCoBound<X extends (self::AinvCyclicCoBound::Y*) →* self::AinvCyclicCoBound::Y* = ((Null) →* dynamic) →* (Null) →* dynamic, Y extends (self::AinvCyclicCoBound::Y*) →* dynamic = (Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::AinvCyclicCoBound<self::AinvCyclicCoBound::X*, self::AinvCyclicCoBound::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method toF<X extends core::Object* = dynamic>(self::toF::X* x) → <Y extends self::toF::X* = dynamic>() →* void
+  return null;
+static method testTypeAliasAsTypeArgument() → void {
+  self::Acov<() →* dynamic, dynamic>* source1;
+  <Y extends self::Acov<() →* dynamic, dynamic>* = dynamic>() →* void fsource1 = self::toF<self::Acov<() →* dynamic, dynamic>*>(source1);
+  <Y extends self::Acov<() →* dynamic, dynamic>* = dynamic>() →* void target1 = fsource1;
+  self::Acon<(Null) →* dynamic, dynamic>* source2;
+  <Y extends self::Acon<(Null) →* dynamic, dynamic>* = dynamic>() →* void fsource2 = self::toF<self::Acon<(Null) →* dynamic, dynamic>*>(source2);
+  <Y extends self::Acon<(Null) →* dynamic, dynamic>* = dynamic>() →* void target2 = fsource2;
+  self::Ainv<(dynamic) →* dynamic, dynamic>* source3;
+  <Y extends self::Ainv<(dynamic) →* dynamic, dynamic>* = dynamic>() →* void fsource3 = self::toF<self::Ainv<(dynamic) →* dynamic, dynamic>*>(source3);
+  <Y extends self::Ainv<(dynamic) →* dynamic, dynamic>* = dynamic>() →* void target3 = fsource3;
+  self::AcovBound<() →* core::num*, core::num*>* source4;
+  <Y extends self::AcovBound<() →* core::num*, core::num*>* = dynamic>() →* void fsource4 = self::toF<self::AcovBound<() →* core::num*, core::num*>*>(source4);
+  <Y extends self::AcovBound<() →* core::num*, core::num*>* = dynamic>() →* void target4 = fsource4;
+  self::AconBound<(Null) →* dynamic, core::num*>* source5;
+  <Y extends self::AconBound<(Null) →* dynamic, core::num*>* = dynamic>() →* void fsource5 = self::toF<self::AconBound<(Null) →* dynamic, core::num*>*>(source5);
+  <Y extends self::AconBound<(Null) →* dynamic, core::num*>* = dynamic>() →* void target5 = fsource5;
+  self::AinvBound<(core::num*) →* core::num*, core::num*>* source6;
+  <Y extends self::AinvBound<(core::num*) →* core::num*, core::num*>* = dynamic>() →* void fsource6 = self::toF<self::AinvBound<(core::num*) →* core::num*, core::num*>*>(source6);
+  <Y extends self::AinvBound<(core::num*) →* core::num*, core::num*>* = dynamic>() →* void target6 = fsource6;
+  self::AcovCyclicBound<() →* self::A<dynamic>*, self::A<dynamic>*>* source7;
+  <Y extends self::AcovCyclicBound<() →* self::A<dynamic>*, self::A<dynamic>*>* = dynamic>() →* void fsource7 = self::toF<self::AcovCyclicBound<() →* self::A<dynamic>*, self::A<dynamic>*>*>(source7);
+  <Y extends self::AcovCyclicBound<() →* self::A<dynamic>*, self::A<dynamic>*>* = dynamic>() →* void target7 = fsource7;
+  self::AconCyclicBound<(Null) →* dynamic, self::A<dynamic>*>* source8;
+  <Y extends self::AconCyclicBound<(Null) →* dynamic, self::A<dynamic>*>* = dynamic>() →* void fsource8 = self::toF<self::AconCyclicBound<(Null) →* dynamic, self::A<dynamic>*>*>(source8);
+  <Y extends self::AconCyclicBound<(Null) →* dynamic, self::A<dynamic>*>* = dynamic>() →* void target8 = fsource8;
+  self::AinvCyclicBound<(self::A<dynamic>*) →* self::A<dynamic>*, self::A<dynamic>*>* source9;
+  self::AcovCyclicCoBound<() →* (Null) →* dynamic, (Null) →* dynamic>* source10;
+  <Y extends self::AcovCyclicCoBound<() →* (Null) →* dynamic, (Null) →* dynamic>* = dynamic>() →* void fsource10 = self::toF<self::AcovCyclicCoBound<() →* (Null) →* dynamic, (Null) →* dynamic>*>(source10);
+  <Y extends self::AcovCyclicCoBound<() →* (Null) →* dynamic, (Null) →* dynamic>* = dynamic>() →* void target10 = fsource10;
+  self::AconCyclicCoBound<(Null) →* dynamic, (Null) →* dynamic>* source11;
+  <Y extends self::AconCyclicCoBound<(Null) →* dynamic, (Null) →* dynamic>* = dynamic>() →* void fsource11 = self::toF<self::AconCyclicCoBound<(Null) →* dynamic, (Null) →* dynamic>*>(source11);
+  <Y extends self::AconCyclicCoBound<(Null) →* dynamic, (Null) →* dynamic>* = dynamic>() →* void target11 = fsource11;
+  self::AinvCyclicCoBound<((Null) →* dynamic) →* (Null) →* dynamic, (Null) →* dynamic>* source12;
+}
+static method testNested() → void {
+  self::B<self::Acov<() →* dynamic, dynamic>*>* source1;
+  <Y extends self::B<self::Acov<() →* dynamic, dynamic>*>* = dynamic>() →* void fsource1 = self::toF<self::B<self::Acov<() →* dynamic, dynamic>*>*>(source1);
+  <Y extends self::B<self::Acov<() →* dynamic, dynamic>*>* = dynamic>() →* void target1 = fsource1;
+  self::B<self::Acon<(Null) →* dynamic, dynamic>*>* source2;
+  <Y extends self::B<self::Acon<(Null) →* dynamic, dynamic>*>* = dynamic>() →* void fsource2 = self::toF<self::B<self::Acon<(Null) →* dynamic, dynamic>*>*>(source2);
+  <Y extends self::B<self::Acon<(Null) →* dynamic, dynamic>*>* = dynamic>() →* void target2 = fsource2;
+  self::B<self::Ainv<(dynamic) →* dynamic, dynamic>*>* source3;
+  <Y extends self::B<self::Ainv<(dynamic) →* dynamic, dynamic>*>* = dynamic>() →* void fsource3 = self::toF<self::B<self::Ainv<(dynamic) →* dynamic, dynamic>*>*>(source3);
+  <Y extends self::B<self::Ainv<(dynamic) →* dynamic, dynamic>*>* = dynamic>() →* void target3 = fsource3;
+  self::B<self::AcovBound<() →* core::num*, core::num*>*>* source4;
+  <Y extends self::B<self::AcovBound<() →* core::num*, core::num*>*>* = dynamic>() →* void fsource4 = self::toF<self::B<self::AcovBound<() →* core::num*, core::num*>*>*>(source4);
+  <Y extends self::B<self::AcovBound<() →* core::num*, core::num*>*>* = dynamic>() →* void target4 = fsource4;
+  self::B<self::AconBound<(Null) →* dynamic, core::num*>*>* source5;
+  <Y extends self::B<self::AconBound<(Null) →* dynamic, core::num*>*>* = dynamic>() →* void fsource5 = self::toF<self::B<self::AconBound<(Null) →* dynamic, core::num*>*>*>(source5);
+  <Y extends self::B<self::AconBound<(Null) →* dynamic, core::num*>*>* = dynamic>() →* void target5 = fsource5;
+  self::B<self::AinvBound<(core::num*) →* core::num*, core::num*>*>* source6;
+  <Y extends self::B<self::AinvBound<(core::num*) →* core::num*, core::num*>*>* = dynamic>() →* void fsource6 = self::toF<self::B<self::AinvBound<(core::num*) →* core::num*, core::num*>*>*>(source6);
+  <Y extends self::B<self::AinvBound<(core::num*) →* core::num*, core::num*>*>* = dynamic>() →* void target6 = fsource6;
+  self::B<self::AcovCyclicBound<() →* self::A<dynamic>*, self::A<dynamic>*>*>* source7;
+  <Y extends self::B<self::AcovCyclicBound<() →* self::A<dynamic>*, self::A<dynamic>*>*>* = dynamic>() →* void fsource7 = self::toF<self::B<self::AcovCyclicBound<() →* self::A<dynamic>*, self::A<dynamic>*>*>*>(source7);
+  <Y extends self::B<self::AcovCyclicBound<() →* self::A<dynamic>*, self::A<dynamic>*>*>* = dynamic>() →* void target7 = fsource7;
+  self::B<self::AconCyclicBound<(Null) →* dynamic, self::A<dynamic>*>*>* source8;
+  <Y extends self::B<self::AconCyclicBound<(Null) →* dynamic, self::A<dynamic>*>*>* = dynamic>() →* void fsource8 = self::toF<self::B<self::AconCyclicBound<(Null) →* dynamic, self::A<dynamic>*>*>*>(source8);
+  <Y extends self::B<self::AconCyclicBound<(Null) →* dynamic, self::A<dynamic>*>*>* = dynamic>() →* void target8 = fsource8;
+  self::B<self::AinvCyclicBound<(self::A<dynamic>*) →* self::A<dynamic>*, self::A<dynamic>*>*>* source9;
+  self::B<self::AcovCyclicCoBound<() →* (Null) →* dynamic, (Null) →* dynamic>*>* source10;
+  <Y extends self::B<self::AcovCyclicCoBound<() →* (Null) →* dynamic, (Null) →* dynamic>*>* = dynamic>() →* void fsource10 = self::toF<self::B<self::AcovCyclicCoBound<() →* (Null) →* dynamic, (Null) →* dynamic>*>*>(source10);
+  <Y extends self::B<self::AcovCyclicCoBound<() →* (Null) →* dynamic, (Null) →* dynamic>*>* = dynamic>() →* void target10 = fsource10;
+  self::B<self::AconCyclicCoBound<(Null) →* dynamic, (Null) →* dynamic>*>* source11;
+  <Y extends self::B<self::AconCyclicCoBound<(Null) →* dynamic, (Null) →* dynamic>*>* = dynamic>() →* void fsource11 = self::toF<self::B<self::AconCyclicCoBound<(Null) →* dynamic, (Null) →* dynamic>*>*>(source11);
+  <Y extends self::B<self::AconCyclicCoBound<(Null) →* dynamic, (Null) →* dynamic>*>* = dynamic>() →* void target11 = fsource11;
+  self::B<self::AinvCyclicCoBound<((Null) →* dynamic) →* (Null) →* dynamic, (Null) →* dynamic>*>* source12;
+}
+static method main() → dynamic {
+  self::testTypeAliasAsTypeArgument();
+  self::testNested();
+}
diff --git a/pkg/front_end/testcases/general/new_as_selector.dart.weak.modular.expect b/pkg/front_end/testcases/general/new_as_selector.dart.weak.modular.expect
new file mode 100644
index 0000000..01083e9
--- /dev/null
+++ b/pkg/front_end/testcases/general/new_as_selector.dart.weak.modular.expect
@@ -0,0 +1,311 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:10:5: Error: 'new' can't be used as an identifier because it's a keyword.
+// Try renaming this to be an identifier that isn't a keyword.
+// int new = 87; // error
+//     ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:17:7: Error: 'new' can't be used as an identifier because it's a keyword.
+// Try renaming this to be an identifier that isn't a keyword.
+//   int new = 42; // error
+//       ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:19:15: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   C() : super.new(); // error
+//               ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:20:20: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   C.named() : this.new(); // error
+//                    ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:31:16: Error: 'new' can't be used as an identifier because it's a keyword.
+// Try renaming this to be an identifier that isn't a keyword.
+//   external int new; // error
+//                ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:23:10: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//     this.new; // error
+//          ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:24:10: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//     this.new(); // error
+//          ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:25:10: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//     this.new<int>(); // error
+//          ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:26:10: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//     this.new = 87; // error
+//          ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:39:11: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   new C().new; // error
+//           ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:40:11: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   new C().new(); // error
+//           ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:41:11: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   new C().new = 87; // error
+//           ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:43:5: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   c.new; // error
+//     ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:44:5: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   c.new = 87; // error
+//     ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:46:7: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   foo.new; // error
+//       ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:47:7: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   foo.new(); // error
+//       ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:48:7: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   foo.new<int>(); // error
+//       ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:49:8: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   foo?.new; // error
+//        ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:50:8: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   foo?.new(); // error
+//        ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:51:8: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   foo?.new<int>(); // error
+//        ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:52:8: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   foo..new; // error
+//        ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:53:8: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   foo..new(); // error
+//        ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:54:8: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   foo..new<int>(); // error
+//        ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:55:9: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   (foo).new; // error
+//         ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:56:9: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   (foo).new(); // error
+//         ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:57:9: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   (foo).new<int>(); // error
+//         ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:58:11: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   prefix1.new; // error
+//           ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:59:11: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   prefix1.new(); // error
+//           ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:60:11: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   prefix1.new<int>(); // error
+//           ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:61:13: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   prefix2.c.new; // error
+//             ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:62:13: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   prefix2.c.new(); // error
+//             ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:63:13: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   prefix2.c.new<int>(); // error
+//             ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:64:8: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   E(0).new; // error
+//        ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:65:8: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   E(0).new(); // error
+//        ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:66:8: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   E(0).new<int>(); // error
+//        ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:67:14: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   unresolved.new; // error
+//              ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:67:3: Error: Undefined name 'unresolved'.
+//   unresolved.new; // error
+//   ^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:68:14: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   unresolved.new(); // error
+//              ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:68:3: Error: Undefined name 'unresolved'.
+//   unresolved.new(); // error
+//   ^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:69:14: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   unresolved.new<int>(); // error
+//              ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:69:3: Error: Undefined name 'unresolved'.
+//   unresolved.new<int>(); // error
+//   ^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:70:5: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   C.new; // error
+//     ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:70:5: Error: Member not found: 'new'.
+//   C.new; // error
+//     ^^^
+//
+// pkg/front_end/testcases/general/new_as_selector.dart:71:5: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   C.new(); // error
+//     ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///new_as_selector.dart" as prefix1;
+import "org-dartlang-testcase:///new_as_selector.dart" deferred as prefix2 hide E;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+}
+class C extends self::Super {
+  field core::int new = 42;
+  constructor •() → self::C
+    : super self::Super::•()
+    ;
+  constructor named() → self::C
+    : this self::C::•()
+    ;
+  method method() → dynamic {
+    this.{self::C::new}{core::int};
+    self::E|call<dynamic>(this.{self::C::new}{core::int});
+    self::E|call<core::int>(this.{self::C::new}{core::int});
+    this.{self::C::new} = 87;
+  }
+}
+extension E on core::int {
+  get new = self::E|get#new;
+  set new = self::E|set#new;
+  method call = self::E|call;
+  tearoff call = self::E|get#call;
+}
+static field core::int new = 87;
+static field self::C c = new self::C::•();
+external static method E|get#new(core::int #this) → core::int;
+external static method E|set#new(core::int #this, core::int #externalFieldValue) → void;
+static method E|call<T extends core::Object? = dynamic>(lowered final core::int #this) → dynamic {}
+static method E|get#call(lowered final core::int #this) → <T extends core::Object? = dynamic>() → dynamic
+  return <T extends core::Object? = dynamic>() → dynamic => self::E|call<T%>(#this);
+static method method(dynamic d) → dynamic
+  return d{dynamic}.new;
+static method test() → dynamic {
+  new self::C::•().{self::C::new}{core::int};
+  self::E|call<dynamic>(new self::C::•().{self::C::new}{core::int});
+  new self::C::•().{self::C::new} = 87;
+  self::C c = new self::C::•();
+  c.{self::C::new}{core::int};
+  c.{self::C::new} = 87;
+  dynamic foo;
+  foo{dynamic}.new;
+  foo{dynamic}.new();
+  foo{dynamic}.new<core::int>();
+  let final dynamic #t1 = foo in #t1 == null ?{dynamic} null : #t1{dynamic}.new;
+  let final dynamic #t2 = foo in #t2 == null ?{dynamic} null : #t2{dynamic}.new();
+  let final dynamic #t3 = foo in #t3 == null ?{dynamic} null : #t3{dynamic}.new<core::int>();
+  let final dynamic #t4 = foo in block {
+    #t4{dynamic}.new;
+  } =>#t4;
+  let final dynamic #t5 = foo in block {
+    #t5{dynamic}.new();
+  } =>#t5;
+  let final dynamic #t6 = foo in block {
+    #t6{dynamic}.new<core::int>();
+  } =>#t6;
+  foo{dynamic}.new;
+  foo{dynamic}.new();
+  foo{dynamic}.new<core::int>();
+  self::new;
+  self::E|call<dynamic>(self::new);
+  self::E|call<core::int>(self::new);
+  let final dynamic #t7 = CheckLibraryIsLoaded(prefix2) in self::c.{self::C::new}{core::int};
+  let final dynamic #t8 = CheckLibraryIsLoaded(prefix2) in self::E|call<dynamic>(self::c.{self::C::new}{core::int});
+  let final dynamic #t9 = CheckLibraryIsLoaded(prefix2) in self::E|call<core::int>(self::c.{self::C::new}{core::int});
+  self::E|get#new(0);
+  self::E|call<dynamic>(self::E|get#new(0));
+  self::E|call<core::int>(self::E|get#new(0));
+  invalid-expression "pkg/front_end/testcases/general/new_as_selector.dart:67:3: Error: Undefined name 'unresolved'.
+  unresolved.new; // error
+  ^^^^^^^^^^"{<invalid>}.new;
+  invalid-expression "pkg/front_end/testcases/general/new_as_selector.dart:68:3: Error: Undefined name 'unresolved'.
+  unresolved.new(); // error
+  ^^^^^^^^^^"{dynamic}.new();
+  invalid-expression "pkg/front_end/testcases/general/new_as_selector.dart:69:3: Error: Undefined name 'unresolved'.
+  unresolved.new<int>(); // error
+  ^^^^^^^^^^"{dynamic}.new<core::int>();
+  invalid-expression "pkg/front_end/testcases/general/new_as_selector.dart:70:5: Error: Member not found: 'new'.
+  C.new; // error
+    ^^^";
+  new self::C::•();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/no_such_method_forwarder.dart.weak.modular.expect b/pkg/front_end/testcases/general/no_such_method_forwarder.dart.weak.modular.expect
new file mode 100644
index 0000000..2fd6b9d
--- /dev/null
+++ b/pkg/front_end/testcases/general/no_such_method_forwarder.dart.weak.modular.expect
@@ -0,0 +1,58 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class X extends core::Object {
+  synthetic constructor •() → self::X*
+    : super core::Object::•()
+    ;
+  method _foo() → void async {
+    await null;
+    core::print("hello");
+  }
+  method foo() → void
+    return this.{self::X::_foo}(){() →* void};
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Y extends core::Object implements self::X {
+  synthetic constructor •() → self::Y*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* _) → void {
+    core::print("Hello from noSuchMethod");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method _foo() → void
+    return this.{self::Y::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* void};
+  no-such-method-forwarder method foo() → void
+    return this.{self::Y::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* void};
+}
+static method main() → dynamic {
+  self::Y* y = new self::Y::•();
+  y.{self::X::foo}(){() →* void};
+}
+
+constants  {
+  #C1 = #org-dartlang-testcase:///no_such_method_forwarder.dart::_foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+  #C5 = #foo
+}
diff --git a/pkg/front_end/testcases/general/no_such_method_private_setter.dart.weak.modular.expect b/pkg/front_end/testcases/general/no_such_method_private_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..180ea5a
--- /dev/null
+++ b/pkg/front_end/testcases/general/no_such_method_private_setter.dart.weak.modular.expect
@@ -0,0 +1,61 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "no_such_method_private_setter_lib.dart" as no_;
+
+import "org-dartlang-testcase:///no_such_method_private_setter_lib.dart";
+
+class Foo extends core::Object implements no_::Bar {
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder get /* from org-dartlang-testcase:///no_such_method_private_setter_lib.dart */ _x() → core::int*
+    return this.{self::Foo::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::int*;
+  no-such-method-forwarder set /* from org-dartlang-testcase:///no_such_method_private_setter_lib.dart */ _x(core::int* value) → void
+    return this.{self::Foo::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+static method main() → dynamic {
+  no_::baz(new self::Foo::•());
+}
+
+library;
+import self as no_;
+import "dart:core" as core;
+
+class Bar extends core::Object {
+  field core::int* _x = null;
+  synthetic constructor •() → no_::Bar*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method baz(no_::Bar* bar) → void {
+  return;
+}
+
+constants  {
+  #C1 = #org-dartlang-testcase:///no_such_method_private_setter.dart::_x
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+  #C5 = #org-dartlang-testcase:///no_such_method_private_setter.dart::_x=
+}
diff --git a/pkg/front_end/testcases/general/non_covariant_checks.dart.weak.modular.expect b/pkg/front_end/testcases/general/non_covariant_checks.dart.weak.modular.expect
new file mode 100644
index 0000000..5f06498
--- /dev/null
+++ b/pkg/front_end/testcases/general/non_covariant_checks.dart.weak.modular.expect
@@ -0,0 +1,493 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::C::T* field1;
+  covariant-by-class field () →* self::C::T* field2;
+  field (self::C::T*) →* void field3;
+  covariant-by-class field (self::C::T*) →* self::C::T* field4;
+  covariant-by-class field () →* () →* self::C::T* field5;
+  field (() →* self::C::T*) →* void field6;
+  covariant-by-class field (() →* self::C::T*) →* self::C::T* field7;
+  covariant-by-class field ((self::C::T*) →* void) →* void field8;
+  covariant-by-class field ((self::C::T*) →* void) →* self::C::T* field9;
+  covariant-by-class field ((self::C::T*) →* self::C::T*) →* void field10;
+  covariant-by-class field ((self::C::T*) →* self::C::T*) →* self::C::T* field11;
+  covariant-by-class field <S extends self::C::T* = dynamic>() →* S* field12;
+  covariant-by-class field <S extends self::C::T* = dynamic>(S*) →* void field13;
+  covariant-by-class field <S extends self::C::T* = dynamic>(S*) →* S* field14;
+  covariant-by-class field (<S extends self::C::T* = dynamic>() →* S*) →* void field15;
+  constructor •(self::C::T* field1) → self::C<self::C::T*>*
+    : self::C::field1 = field1, self::C::field2 = () → self::C::T* => field1, self::C::field3 = (self::C::T* t) → Null {}, self::C::field4 = (self::C::T* t) → self::C::T* => t, self::C::field5 = () → () →* self::C::T* => () → self::C::T* => field1, self::C::field6 = (() →* self::C::T* f) → Null {}, self::C::field7 = (() →* self::C::T* f) → self::C::T* => field1, self::C::field8 = ((self::C::T*) →* void f) → Null {}, self::C::field9 = ((self::C::T*) →* void f) → self::C::T* => field1, self::C::field10 = ((self::C::T*) →* self::C::T* f) → Null {}, self::C::field11 = ((self::C::T*) →* self::C::T* f) → self::C::T* => field1, self::C::field12 = <S extends self::C::T*>() → Null => null, self::C::field13 = <S extends self::C::T*>(S* s) → Null {}, self::C::field14 = <S extends self::C::T*>(S* s) → S* => s, self::C::field15 = (<S extends self::C::T*>() →* S* f) → Null {}, super core::Object::•()
+    ;
+  get getter1() → self::C::T*
+    return this.{self::C::field1}{self::C::T*};
+  get getter2() → () →* self::C::T*
+    return this.{self::C::field2}{() →* self::C::T*};
+  get getter3() → (self::C::T*) →* void
+    return this.{self::C::field3}{(self::C::T*) →* void};
+  get getter4() → (self::C::T*) →* self::C::T*
+    return this.{self::C::field4}{(self::C::T*) →* self::C::T*};
+  get getter5() → () →* () →* self::C::T*
+    return this.{self::C::field5}{() →* () →* self::C::T*};
+  get getter6() → (() →* self::C::T*) →* void
+    return this.{self::C::field6}{(() →* self::C::T*) →* void};
+  get getter7() → (() →* self::C::T*) →* self::C::T*
+    return this.{self::C::field7}{(() →* self::C::T*) →* self::C::T*};
+  get getter8() → ((self::C::T*) →* void) →* void
+    return this.{self::C::field8}{((self::C::T*) →* void) →* void};
+  get getter9() → ((self::C::T*) →* void) →* self::C::T*
+    return this.{self::C::field9}{((self::C::T*) →* void) →* self::C::T*};
+  get getter10() → ((self::C::T*) →* self::C::T*) →* void
+    return this.{self::C::field10}{((self::C::T*) →* self::C::T*) →* void};
+  get getter11() → ((self::C::T*) →* self::C::T*) →* self::C::T*
+    return this.{self::C::field11}{((self::C::T*) →* self::C::T*) →* self::C::T*};
+  get getter12() → <S extends self::C::T* = dynamic>() →* S*
+    return this.{self::C::field12}{<S extends self::C::T* = dynamic>() →* S*};
+  get getter13() → <S extends self::C::T* = dynamic>(S*) →* void
+    return this.{self::C::field13}{<S extends self::C::T* = dynamic>(S*) →* void};
+  get getter14() → <S extends self::C::T* = dynamic>(S*) →* S*
+    return this.{self::C::field14}{<S extends self::C::T* = dynamic>(S*) →* S*};
+  get getter15() → (<S extends self::C::T* = dynamic>() →* S*) →* void
+    return this.{self::C::field15}{(<S extends self::C::T* = dynamic>() →* S*) →* void};
+  set setter1(covariant-by-class self::C::T* value) → void {
+    this.{self::C::field1} = value;
+  }
+  set setter2(covariant-by-class () →* self::C::T* value) → void {
+    this.{self::C::field2} = value;
+  }
+  set setter3((self::C::T*) →* void value) → void {
+    this.{self::C::field3} = value;
+  }
+  set setter4(covariant-by-class (self::C::T*) →* self::C::T* value) → void {
+    this.{self::C::field4} = value;
+  }
+  set setter5(covariant-by-class () →* () →* self::C::T* value) → void {
+    this.{self::C::field5} = value;
+  }
+  set setter6((() →* self::C::T*) →* void value) → void {
+    this.{self::C::field6} = value;
+  }
+  set setter7(covariant-by-class (() →* self::C::T*) →* self::C::T* value) → void {
+    this.{self::C::field7} = value;
+  }
+  set setter8(covariant-by-class ((self::C::T*) →* void) →* void value) → void {
+    this.{self::C::field8} = value;
+  }
+  set setter9(covariant-by-class ((self::C::T*) →* void) →* self::C::T* value) → void {
+    this.{self::C::field9} = value;
+  }
+  set setter10(covariant-by-class ((self::C::T*) →* self::C::T*) →* void value) → void {
+    this.{self::C::field10} = value;
+  }
+  set setter11(covariant-by-class ((self::C::T*) →* self::C::T*) →* self::C::T* value) → void {
+    this.{self::C::field11} = value;
+  }
+  set setter12(covariant-by-class <S extends self::C::T* = dynamic>() →* S* value) → void {
+    this.{self::C::field12} = value;
+  }
+  set setter13(covariant-by-class <S extends self::C::T* = dynamic>(S*) →* void value) → void {
+    this.{self::C::field13} = value;
+  }
+  set setter14(covariant-by-class <S extends self::C::T* = dynamic>(S*) →* S* value) → void {
+    this.{self::C::field14} = value;
+  }
+  set setter15(covariant-by-class (<S extends self::C::T* = dynamic>() →* S*) →* void value) → void {
+    this.{self::C::field15} = value;
+  }
+  method method1(covariant-by-class self::C::T* value) → void {
+    this.{self::C::field1} = value;
+  }
+  method method2(covariant-by-class () →* self::C::T* value) → void {
+    this.{self::C::field2} = value;
+  }
+  method method3((self::C::T*) →* void value) → void {
+    this.{self::C::field3} = value;
+  }
+  method method4(covariant-by-class (self::C::T*) →* self::C::T* value) → void {
+    this.{self::C::field4} = value;
+  }
+  method method5(covariant-by-class () →* () →* self::C::T* value) → void {
+    this.{self::C::field5} = value;
+  }
+  method method6((() →* self::C::T*) →* void value) → void {
+    this.{self::C::field6} = value;
+  }
+  method method7(covariant-by-class (() →* self::C::T*) →* self::C::T* value) → void {
+    this.{self::C::field7} = value;
+  }
+  method method8(covariant-by-class ((self::C::T*) →* void) →* void value) → void {
+    this.{self::C::field8} = value;
+  }
+  method method9(covariant-by-class ((self::C::T*) →* void) →* self::C::T* value) → void {
+    this.{self::C::field9} = value;
+  }
+  method method10(covariant-by-class ((self::C::T*) →* self::C::T*) →* void value) → void {
+    this.{self::C::field10} = value;
+  }
+  method method11(covariant-by-class ((self::C::T*) →* self::C::T*) →* self::C::T* value) → void {
+    this.{self::C::field11} = value;
+  }
+  method method12(covariant-by-class <S extends self::C::T* = dynamic>() →* S* value) → void {
+    this.{self::C::field12} = value;
+  }
+  method method13(covariant-by-class <S extends self::C::T* = dynamic>(S*) →* void value) → void {
+    this.{self::C::field13} = value;
+  }
+  method method14(covariant-by-class <S extends self::C::T* = dynamic>(S*) →* S* value) → void {
+    this.{self::C::field14} = value;
+  }
+  method method15(covariant-by-class (<S extends self::C::T* = dynamic>() →* S*) →* void value) → void {
+    this.{self::C::field15} = value;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C<core::num*>* c = new self::C::•<core::int*>(0);
+  c.{self::C::field1}{core::num*};
+  c.{self::C::field2}{() →* core::num*};
+  try {
+    c.{self::C::field3}{(core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::field4}{(core::num*) →* core::num*} as{TypeError,CovarianceCheck} (core::num*) →* core::num*;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  c.{self::C::field5}{() →* () →* core::num*};
+  try {
+    c.{self::C::field6}{(() →* core::num*) →* void} as{TypeError,CovarianceCheck} (() →* core::num*) →* void;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::field7}{(() →* core::num*) →* core::num*} as{TypeError,CovarianceCheck} (() →* core::num*) →* core::num*;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  c.{self::C::field8}{((core::num*) →* void) →* void};
+  c.{self::C::field9}{((core::num*) →* void) →* core::num*};
+  try {
+    c.{self::C::field10}{((core::num*) →* core::num*) →* void} as{TypeError,CovarianceCheck} ((core::num*) →* core::num*) →* void;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::field11}{((core::num*) →* core::num*) →* core::num*} as{TypeError,CovarianceCheck} ((core::num*) →* core::num*) →* core::num*;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::field12}{<S extends core::num* = dynamic>() →* S*} as{TypeError,CovarianceCheck} <S extends core::num* = dynamic>() →* S*;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::field13}{<S extends core::num* = dynamic>(S*) →* void} as{TypeError,CovarianceCheck} <S extends core::num* = dynamic>(S*) →* void;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::field14}{<S extends core::num* = dynamic>(S*) →* S*} as{TypeError,CovarianceCheck} <S extends core::num* = dynamic>(S*) →* S*;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::field15}{(<S extends core::num* = dynamic>() →* S*) →* void} as{TypeError,CovarianceCheck} (<S extends core::num* = dynamic>() →* S*) →* void;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  c.{self::C::getter1}{core::num*};
+  c.{self::C::getter2}{() →* core::num*};
+  try {
+    c.{self::C::getter3}{(core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::getter4}{(core::num*) →* core::num*} as{TypeError,CovarianceCheck} (core::num*) →* core::num*;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  c.{self::C::getter5}{() →* () →* core::num*};
+  try {
+    c.{self::C::getter6}{(() →* core::num*) →* void} as{TypeError,CovarianceCheck} (() →* core::num*) →* void;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::getter7}{(() →* core::num*) →* core::num*} as{TypeError,CovarianceCheck} (() →* core::num*) →* core::num*;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  c.{self::C::getter8}{((core::num*) →* void) →* void};
+  c.{self::C::getter9}{((core::num*) →* void) →* core::num*};
+  try {
+    c.{self::C::getter10}{((core::num*) →* core::num*) →* void} as{TypeError,CovarianceCheck} ((core::num*) →* core::num*) →* void;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::getter11}{((core::num*) →* core::num*) →* core::num*} as{TypeError,CovarianceCheck} ((core::num*) →* core::num*) →* core::num*;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::getter12}{<S extends core::num* = dynamic>() →* S*} as{TypeError,CovarianceCheck} <S extends core::num* = dynamic>() →* S*;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::getter13}{<S extends core::num* = dynamic>(S*) →* void} as{TypeError,CovarianceCheck} <S extends core::num* = dynamic>(S*) →* void;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::getter14}{<S extends core::num* = dynamic>(S*) →* S*} as{TypeError,CovarianceCheck} <S extends core::num* = dynamic>(S*) →* S*;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::getter15}{(<S extends core::num* = dynamic>() →* S*) →* void} as{TypeError,CovarianceCheck} (<S extends core::num* = dynamic>() →* S*) →* void;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::setter1} = 0.5;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::setter2} = () → core::double* => 0.5;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  c.{self::C::setter3} = (core::num* n) → Null {};
+  try {
+    c.{self::C::setter4} = (core::num* n) → core::double* => 0.5;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::setter5} = () → () →* core::double* => () → core::double* => 0.5;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  c.{self::C::setter6} = (() →* core::num* f) → Null {};
+  try {
+    c.{self::C::setter7} = (() →* core::num* f) → core::double* => 0.5;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::setter8} = ((core::double*) →* void f) → Null {};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::setter9} = ((core::double*) →* void f) → core::double* => 0.5;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::setter10} = ((core::double*) →* core::num* f) → Null {};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::setter11} = ((core::double*) →* core::num* f) → core::double* => 0.5;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::setter12} = <S extends core::num*>() → Null => null;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::setter13} = <S extends core::num*>(S* s) → Null {};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::setter14} = <S extends core::num*>(S* s) → S* => s;
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::setter15} = (<S extends core::num*>() →* S* f) → Null {};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::method1}(0.5){(core::num*) →* void};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::method2}(() → core::double* => 0.5){(() →* core::num*) →* void};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  c.{self::C::method3}((core::num* n) → Null {}){((core::num*) →* void) →* void};
+  try {
+    c.{self::C::method4}((core::num* n) → core::double* => 0.5){((core::num*) →* core::num*) →* void};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::method5}(() → () →* core::double* => () → core::double* => 0.5){(() →* () →* core::num*) →* void};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  c.{self::C::method6}((() →* core::num* f) → Null {}){((() →* core::num*) →* void) →* void};
+  try {
+    c.{self::C::method7}((() →* core::num* f) → core::double* => 0.5){((() →* core::num*) →* core::num*) →* void};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::method8}(((core::double*) →* void f) → Null {}){(((core::num*) →* void) →* void) →* void};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::method9}(((core::double*) →* void f) → core::double* => 0.5){(((core::num*) →* void) →* core::num*) →* void};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::method10}(((core::double*) →* core::num* f) → Null {}){(((core::num*) →* core::num*) →* void) →* void};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::method11}(((core::double*) →* core::num* f) → core::double* => 0.5){(((core::num*) →* core::num*) →* core::num*) →* void};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::method12}(<S extends core::num*>() → Null => null){(<S extends core::num* = dynamic>() →* S*) →* void};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::method13}(<S extends core::num*>(S* s) → Null {}){(<S extends core::num* = dynamic>(S*) →* void) →* void};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::method14}(<S extends core::num*>(S* s) → S* => s){(<S extends core::num* = dynamic>(S*) →* S*) →* void};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+  try {
+    c.{self::C::method15}((<S extends core::num*>() →* S* f) → Null {}){((<S extends core::num* = dynamic>() →* S*) →* void) →* void};
+    throw "TypeError expected";
+  }
+  on core::TypeError* catch(final core::TypeError* e) {
+    core::print(e);
+  }
+}
diff --git a/pkg/front_end/testcases/general/nsm_covariance.dart.weak.modular.expect b/pkg/front_end/testcases/general/nsm_covariance.dart.weak.modular.expect
new file mode 100644
index 0000000..ac4c6e4
--- /dev/null
+++ b/pkg/front_end/testcases/general/nsm_covariance.dart.weak.modular.expect
@@ -0,0 +1,247 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "nsm_covariance_lib.dart" as nsm;
+
+import "org-dartlang-testcase:///nsm_covariance_lib.dart";
+
+abstract class D1 extends core::Object implements nsm::A<core::int*>, nsm::B {
+  synthetic constructor •() → self::D1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract forwarding-stub method _method1(core::int* a, covariant-by-declaration core::int* b, covariant-by-class core::int* c, covariant-by-declaration covariant-by-class core::int* d) → void;
+  abstract forwarding-stub method _method2({core::int* a = #C1, covariant-by-declaration core::int* b = #C1, covariant-by-class core::int* c = #C1, covariant-by-declaration covariant-by-class core::int* d = #C1}) → void;
+  abstract forwarding-stub method _method3(covariant-by-declaration core::int* a, covariant-by-class core::int* b) → void;
+  abstract forwarding-stub method _method4({covariant-by-declaration core::int* a = #C1, covariant-by-class core::int* b = #C1}) → void;
+}
+abstract class D2 extends core::Object implements nsm::B, nsm::A<core::int*> {
+  synthetic constructor •() → self::D2*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract forwarding-stub method _method1(core::int* x, covariant-by-declaration core::int* y, covariant-by-class core::int* z, covariant-by-declaration covariant-by-class core::int* w) → void;
+  abstract forwarding-stub method _method2({core::int* a = #C1, covariant-by-declaration core::int* b = #C1, covariant-by-class core::int* c = #C1, covariant-by-declaration covariant-by-class core::int* d = #C1}) → void;
+  abstract forwarding-stub method _method3(covariant-by-declaration core::int* x, covariant-by-class core::int* y) → void;
+  abstract forwarding-stub method _method4({covariant-by-declaration core::int* a = #C1, covariant-by-class core::int* b = #C1}) → void;
+}
+class D3 extends core::Object implements nsm::A<core::int*>, nsm::B {
+  synthetic constructor •() → self::D3*
+    : super core::Object::•()
+    ;
+  @#C2
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method _method1(core::int* a, covariant-by-declaration core::int* b, covariant-by-class core::int* c, covariant-by-declaration covariant-by-class core::int* d) → void
+    return this.{self::D3::noSuchMethod}(new core::_InvocationMirror::_withType(#C3, 0, #C4, core::List::unmodifiable<dynamic>(<dynamic>[a, b, c, d]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method _method2({core::int* a = #C1, covariant-by-declaration core::int* b = #C1, covariant-by-class core::int* c = #C1, covariant-by-declaration covariant-by-class core::int* d = #C1}) → void
+    return this.{self::D3::noSuchMethod}(new core::_InvocationMirror::_withType(#C6, 0, #C4, #C7, core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C8: a, #C9: b, #C10: c, #C11: d}))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method _method3(covariant-by-declaration core::int* a, covariant-by-class core::int* b) → void
+    return this.{self::D3::noSuchMethod}(new core::_InvocationMirror::_withType(#C12, 0, #C4, core::List::unmodifiable<dynamic>(<dynamic>[a, b]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method _method4({covariant-by-declaration core::int* a = #C1, covariant-by-class core::int* b = #C1}) → void
+    return this.{self::D3::noSuchMethod}(new core::_InvocationMirror::_withType(#C13, 0, #C4, #C7, core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C8: a, #C9: b}))){(core::Invocation*) →* dynamic};
+}
+class D4 extends core::Object implements nsm::B, nsm::A<core::int*> {
+  synthetic constructor •() → self::D4*
+    : super core::Object::•()
+    ;
+  @#C2
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method _method1(core::int* x, covariant-by-declaration core::int* y, covariant-by-class core::int* z, covariant-by-declaration covariant-by-class core::int* w) → void
+    return this.{self::D4::noSuchMethod}(new core::_InvocationMirror::_withType(#C3, 0, #C4, core::List::unmodifiable<dynamic>(<dynamic>[x, y, z, w]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method _method2({core::int* a = #C1, covariant-by-declaration core::int* b = #C1, covariant-by-class core::int* c = #C1, covariant-by-declaration covariant-by-class core::int* d = #C1}) → void
+    return this.{self::D4::noSuchMethod}(new core::_InvocationMirror::_withType(#C6, 0, #C4, #C7, core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C8: a, #C9: b, #C10: c, #C11: d}))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method _method3(covariant-by-declaration core::int* x, covariant-by-class core::int* y) → void
+    return this.{self::D4::noSuchMethod}(new core::_InvocationMirror::_withType(#C12, 0, #C4, core::List::unmodifiable<dynamic>(<dynamic>[x, y]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method _method4({covariant-by-declaration core::int* a = #C1, covariant-by-class core::int* b = #C1}) → void
+    return this.{self::D4::noSuchMethod}(new core::_InvocationMirror::_withType(#C13, 0, #C4, #C7, core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C8: a, #C9: b}))){(core::Invocation*) →* dynamic};
+}
+static method main() → dynamic {}
+
+library;
+import self as nsm;
+import "dart:core" as core;
+
+abstract class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → nsm::A<nsm::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract method _method1(core::int* a, core::int* b, covariant-by-class nsm::A::T* c, covariant-by-class nsm::A::T* d) → void;
+  abstract method _method2({core::int* a = #C1, core::int* b = #C1, covariant-by-class nsm::A::T* c = #C1, covariant-by-class nsm::A::T* d = #C1}) → void;
+  abstract method _method3(core::int* a, covariant-by-class nsm::A::T* b) → void;
+  abstract method _method4({core::int* a = #C1, covariant-by-class nsm::A::T* b = #C1}) → void;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object {
+  synthetic constructor •() → nsm::B*
+    : super core::Object::•()
+    ;
+  abstract method _method1(core::int* x, covariant-by-declaration core::int* y, core::int* z, covariant-by-declaration core::int* w) → void;
+  abstract method _method2({core::int* a = #C1, covariant-by-declaration core::int* b = #C1, core::int* c = #C1, covariant-by-declaration core::int* d = #C1}) → void;
+  abstract method _method3(covariant-by-declaration core::int* x, core::int* y) → void;
+  abstract method _method4({covariant-by-declaration core::int* a = #C1, core::int* b = #C1}) → void;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C1 extends core::Object implements nsm::A<core::int*>, nsm::B {
+  synthetic constructor •() → nsm::C1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract forwarding-stub method _method1(core::int* a, covariant-by-declaration core::int* b, covariant-by-class core::int* c, covariant-by-declaration covariant-by-class core::int* d) → void;
+  abstract forwarding-stub method _method2({core::int* a = #C1, covariant-by-declaration core::int* b = #C1, covariant-by-class core::int* c = #C1, covariant-by-declaration covariant-by-class core::int* d = #C1}) → void;
+  abstract forwarding-stub method _method3(covariant-by-declaration core::int* a, covariant-by-class core::int* b) → void;
+  abstract forwarding-stub method _method4({covariant-by-declaration core::int* a = #C1, covariant-by-class core::int* b = #C1}) → void;
+}
+abstract class C2 extends core::Object implements nsm::B, nsm::A<core::int*> {
+  synthetic constructor •() → nsm::C2*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract forwarding-stub method _method1(core::int* x, covariant-by-declaration core::int* y, covariant-by-class core::int* z, covariant-by-declaration covariant-by-class core::int* w) → void;
+  abstract forwarding-stub method _method2({core::int* a = #C1, covariant-by-declaration core::int* b = #C1, covariant-by-class core::int* c = #C1, covariant-by-declaration covariant-by-class core::int* d = #C1}) → void;
+  abstract forwarding-stub method _method3(covariant-by-declaration core::int* x, covariant-by-class core::int* y) → void;
+  abstract forwarding-stub method _method4({covariant-by-declaration core::int* a = #C1, covariant-by-class core::int* b = #C1}) → void;
+}
+class C3 extends core::Object implements nsm::A<core::int*>, nsm::B {
+  synthetic constructor •() → nsm::C3*
+    : super core::Object::•()
+    ;
+  @#C2
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method _method1(core::int* a, covariant-by-declaration core::int* b, covariant-by-class core::int* c, covariant-by-declaration covariant-by-class core::int* d) → void
+    return this.{nsm::C3::noSuchMethod}(new core::_InvocationMirror::_withType(#C14, 0, #C4, core::List::unmodifiable<dynamic>(<dynamic>[a, b, c, d]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method _method2({core::int* a = #C1, covariant-by-declaration core::int* b = #C1, covariant-by-class core::int* c = #C1, covariant-by-declaration covariant-by-class core::int* d = #C1}) → void
+    return this.{nsm::C3::noSuchMethod}(new core::_InvocationMirror::_withType(#C15, 0, #C4, #C7, core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C8: a, #C9: b, #C10: c, #C11: d}))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method _method3(covariant-by-declaration core::int* a, covariant-by-class core::int* b) → void
+    return this.{nsm::C3::noSuchMethod}(new core::_InvocationMirror::_withType(#C16, 0, #C4, core::List::unmodifiable<dynamic>(<dynamic>[a, b]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method _method4({covariant-by-declaration core::int* a = #C1, covariant-by-class core::int* b = #C1}) → void
+    return this.{nsm::C3::noSuchMethod}(new core::_InvocationMirror::_withType(#C17, 0, #C4, #C7, core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C8: a, #C9: b}))){(core::Invocation*) →* dynamic};
+}
+class C4 extends core::Object implements nsm::B, nsm::A<core::int*> {
+  synthetic constructor •() → nsm::C4*
+    : super core::Object::•()
+    ;
+  @#C2
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method _method1(core::int* x, covariant-by-declaration core::int* y, covariant-by-class core::int* z, covariant-by-declaration covariant-by-class core::int* w) → void
+    return this.{nsm::C4::noSuchMethod}(new core::_InvocationMirror::_withType(#C14, 0, #C4, core::List::unmodifiable<dynamic>(<dynamic>[x, y, z, w]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method _method2({core::int* a = #C1, covariant-by-declaration core::int* b = #C1, covariant-by-class core::int* c = #C1, covariant-by-declaration covariant-by-class core::int* d = #C1}) → void
+    return this.{nsm::C4::noSuchMethod}(new core::_InvocationMirror::_withType(#C15, 0, #C4, #C7, core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C8: a, #C9: b, #C10: c, #C11: d}))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method _method3(covariant-by-declaration core::int* x, covariant-by-class core::int* y) → void
+    return this.{nsm::C4::noSuchMethod}(new core::_InvocationMirror::_withType(#C16, 0, #C4, core::List::unmodifiable<dynamic>(<dynamic>[x, y]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method _method4({covariant-by-declaration core::int* a = #C1, covariant-by-class core::int* b = #C1}) → void
+    return this.{nsm::C4::noSuchMethod}(new core::_InvocationMirror::_withType(#C17, 0, #C4, #C7, core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C8: a, #C9: b}))){(core::Invocation*) →* dynamic};
+}
+
+constants  {
+  #C1 = null
+  #C2 = core::_Override {}
+  #C3 = #org-dartlang-testcase:///nsm_covariance.dart::_method1
+  #C4 = <core::Type*>[]
+  #C5 = <core::Symbol*, dynamic>{)
+  #C6 = #org-dartlang-testcase:///nsm_covariance.dart::_method2
+  #C7 = <dynamic>[]
+  #C8 = #a
+  #C9 = #b
+  #C10 = #c
+  #C11 = #d
+  #C12 = #org-dartlang-testcase:///nsm_covariance.dart::_method3
+  #C13 = #org-dartlang-testcase:///nsm_covariance.dart::_method4
+  #C14 = #org-dartlang-testcase:///nsm_covariance_lib.dart::_method1
+  #C15 = #org-dartlang-testcase:///nsm_covariance_lib.dart::_method2
+  #C16 = #org-dartlang-testcase:///nsm_covariance_lib.dart::_method3
+  #C17 = #org-dartlang-testcase:///nsm_covariance_lib.dart::_method4
+}
diff --git a/pkg/front_end/testcases/general/null_aware.dart.weak.modular.expect b/pkg/front_end/testcases/general/null_aware.dart.weak.modular.expect
new file mode 100644
index 0000000..6e39869
--- /dev/null
+++ b/pkg/front_end/testcases/general/null_aware.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  field core::int* field = null;
+  static field core::int* staticField = null;
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::Foo* foo = new self::Foo::•();
+  let final self::Foo* #t1 = foo in #t1 == null ?{core::int*} null : #t1.{self::Foo::field} = 5;
+  self::Foo::staticField = 5;
+  let final self::Foo* #t2 = foo in #t2.{self::Foo::field}{core::int*} == null ?{core::int*} #t2.{self::Foo::field} = 5 : null;
+  self::Foo::staticField == null ?{core::int*} self::Foo::staticField = 5 : null;
+  let final self::Foo* #t3 = foo in #t3 == null ?{core::int*} null : #t3.{self::Foo::field}{core::int*} == null ?{core::int*} #t3.{self::Foo::field} = 5 : null;
+  self::Foo::staticField == null ?{core::int*} self::Foo::staticField = 5 : null;
+  core::int* intValue = let final core::int* #t4 = foo.{self::Foo::field}{core::int*} in #t4 == null ?{core::int*} 6 : #t4;
+  core::num* numValue = let final core::int* #t5 = foo.{self::Foo::field}{core::int*} in #t5 == null ?{core::num*} 4.5 : #t5;
+}
diff --git a/pkg/front_end/testcases/general/null_aware_for_in.dart.weak.modular.expect b/pkg/front_end/testcases/general/null_aware_for_in.dart.weak.modular.expect
new file mode 100644
index 0000000..46f5652
--- /dev/null
+++ b/pkg/front_end/testcases/general/null_aware_for_in.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  dynamic o;
+  if(false) {
+    for (final dynamic #t1 in (let final dynamic #t2 = o in #t2 == null ?{dynamic} null : #t2{dynamic}.iterable) as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      self::Class* c = #t1 as{TypeError,ForDynamic} self::Class*;
+    }
+  }
+}
diff --git a/pkg/front_end/testcases/general/null_aware_postfix.dart.weak.modular.expect b/pkg/front_end/testcases/general/null_aware_postfix.dart.weak.modular.expect
new file mode 100644
index 0000000..b31646a
--- /dev/null
+++ b/pkg/front_end/testcases/general/null_aware_postfix.dart.weak.modular.expect
@@ -0,0 +1,47 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field self::B* b = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  operator +(core::int* i) → self::C*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+static method main() → dynamic {
+  self::A* a;
+  let final self::A* #t1 = a in #t1 == null ?{self::B*} null : #t1.{self::A::b} = #t1.{self::A::b}{self::B*}.{self::B::+}(1){(core::int*) →* self::C*};
+  self::C* c = (let final self::A* #t2 = a in #t2 == null ?{self::B*} null : let final self::B* #t3 = #t2.{self::A::b}{self::B*} in let final void #t4 = #t2.{self::A::b} = #t3.{self::B::+}(1){(core::int*) →* self::C*} in #t3) as{TypeError} self::C*;
+}
diff --git a/pkg/front_end/testcases/general/null_aware_spread.dart.weak.modular.expect b/pkg/front_end/testcases/general/null_aware_spread.dart.weak.modular.expect
new file mode 100644
index 0000000..01b31a0
--- /dev/null
+++ b/pkg/front_end/testcases/general/null_aware_spread.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+static method nullAwareListSpread(core::List<core::String*>* list) → dynamic {
+  list = block {
+    final core::List<core::String*>* #t1 = <core::String*>["foo"];
+    final core::Iterable<core::String*>* #t2 = list;
+    if(!(#t2 == null))
+      #t1.{core::List::addAll}{Invariant}(#t2){(core::Iterable<core::String*>*) →* void};
+  } =>#t1;
+}
+static method nullAwareSetSpread(core::Set<core::String*>* set) → dynamic {
+  set = block {
+    final core::Set<core::String*>* #t3 = col::LinkedHashSet::•<core::String*>();
+    #t3.{core::Set::add}{Invariant}("foo"){(core::String*) →* core::bool*};
+    final core::Iterable<core::String*>* #t4 = set;
+    if(!(#t4 == null))
+      #t3.{core::Set::addAll}{Invariant}(#t4){(core::Iterable<core::String*>*) →* void};
+  } =>#t3;
+}
+static method nullAwareMapSpread(core::Map<core::int*, core::String*>* map) → dynamic {
+  map = block {
+    final core::Map<core::int*, core::String*>* #t5 = <core::int*, core::String*>{};
+    #t5.{core::Map::[]=}{Invariant}(0, "foo"){(core::int*, core::String*) →* void};
+    final core::Map<core::int*, core::String*>* #t6 = map;
+    if(!(#t6 == null))
+      for (final core::MapEntry<core::int*, core::String*>* #t7 in #t6.{core::Map::entries}{core::Iterable<core::MapEntry<core::int*, core::String*>>})
+        #t5.{core::Map::[]=}{Invariant}(#t7.{core::MapEntry::key}{core::int*}, #t7.{core::MapEntry::value}{core::String*}){(core::int*, core::String*) →* void};
+  } =>#t5;
+}
+static method main() → dynamic {
+  self::nullAwareListSpread(null);
+  self::nullAwareSetSpread(null);
+  self::nullAwareMapSpread(null);
+}
diff --git a/pkg/front_end/testcases/general/null_aware_super.dart.weak.modular.expect b/pkg/front_end/testcases/general/null_aware_super.dart.weak.modular.expect
new file mode 100644
index 0000000..2e47743
--- /dev/null
+++ b/pkg/front_end/testcases/general/null_aware_super.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/null_aware_super.dart:10:18: Error: The operator '?.' cannot be used with 'super' because 'super' cannot be null.
+// Try replacing '?.' with '.'
+//   Class() : super?.named();
+//                  ^^
+//
+// pkg/front_end/testcases/general/null_aware_super.dart:10:18: Error: Cannot use '?.' here.
+// Try using '.'.
+//   Class() : super?.named();
+//                  ^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  constructor named() → self::Super
+    : super core::Object::•()
+    ;
+}
+class Class extends self::Super {
+  constructor •() → self::Class
+    : super self::Super::named()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/null_check_type_variable_type.dart.weak.modular.expect b/pkg/front_end/testcases/general/null_check_type_variable_type.dart.weak.modular.expect
new file mode 100644
index 0000000..7426716
--- /dev/null
+++ b/pkg/front_end/testcases/general/null_check_type_variable_type.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+class Element extends core::Object {
+  synthetic constructor •() → self::Element
+    : super core::Object::•()
+    ;
+}
+class Class<E extends self::Element?> extends core::Object {
+  covariant-by-class field self::Class::E? element;
+  constructor •(self::Class::E? element) → self::Class<self::Class::E%>
+    : self::Class::element = element, super core::Object::•()
+    ;
+  method setElement(covariant-by-class self::Class::E? element) → void {
+    if(!(this.{self::Class::element}{self::Class::E?} =={core::Object::==}{(core::Object) → core::bool} element)) {
+      this.{self::Class::element} = element;
+      core::Set<self::Element> elements = col::LinkedHashSet::•<self::Element>();
+      if(!(element == null)) {
+        elements.{core::Set::add}(element{self::Class::E% & self::Element /* '%' & '!' = '!' */}){(self::Element) → core::bool};
+      }
+      if(!(this.{self::Class::element}{self::Class::E?} == null)) {
+        elements.{core::Set::add}(this.{self::Class::element}{self::Class::E?}!){(self::Element) → core::bool};
+      }
+    }
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/null_safety_invalid_experiment.dart.weak.modular.expect b/pkg/front_end/testcases/general/null_safety_invalid_experiment.dart.weak.modular.expect
new file mode 100644
index 0000000..9f0d253
--- /dev/null
+++ b/pkg/front_end/testcases/general/null_safety_invalid_experiment.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/null_safety_invalid_experiment.dart:5:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+// int? i;
+//    ^
+// pkg/front_end/testcases/general/null_safety_invalid_experiment.dart:4:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.9
+// ^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static field core::int? i;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/null_safety_invalid_experiment_and_language_version.dart.weak.modular.expect b/pkg/front_end/testcases/general/null_safety_invalid_experiment_and_language_version.dart.weak.modular.expect
new file mode 100644
index 0000000..14c6cd9
--- /dev/null
+++ b/pkg/front_end/testcases/general/null_safety_invalid_experiment_and_language_version.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/null_safety_invalid_experiment_and_language_version.dart:7:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+// int? i;
+//    ^
+// pkg/front_end/testcases/general/null_safety_invalid_experiment_and_language_version.dart:4:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.9
+// ^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static field core::int? i;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/operator_method_not_found.dart.weak.modular.expect b/pkg/front_end/testcases/general/operator_method_not_found.dart.weak.modular.expect
new file mode 100644
index 0000000..eb609ae
--- /dev/null
+++ b/pkg/front_end/testcases/general/operator_method_not_found.dart.weak.modular.expect
@@ -0,0 +1,367 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:36:10: Error: 'foo' isn't a type.
+//   print(<foo);
+//          ^^^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:36:10: Error: Expected '>' after this.
+//   print(<foo);
+//          ^^^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:36:13: Error: Expected '[' before this.
+//   print(<foo);
+//             ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:37:9: Error: Expected an identifier, but got '>'.
+// Try inserting an identifier before '>'.
+//   print(>foo);
+//         ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:38:9: Error: Expected an identifier, but got '<='.
+// Try inserting an identifier before '<='.
+//   print(<=foo);
+//         ^^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:39:9: Error: Expected an identifier, but got '>='.
+// Try inserting an identifier before '>='.
+//   print(>=foo);
+//         ^^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:40:9: Error: Expected an identifier, but got '=='.
+// Try inserting an identifier before '=='.
+//   print(==foo);
+//         ^^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:41:9: Error: '+' is not a prefix operator.
+// Try removing '+'.
+//   print(+foo);
+//         ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:42:9: Error: Expected an identifier, but got '/'.
+// Try inserting an identifier before '/'.
+//   print(/foo);
+//         ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:43:9: Error: Expected an identifier, but got '~/'.
+// Try inserting an identifier before '~/'.
+//   print(~/foo);
+//         ^^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:44:9: Error: Expected an identifier, but got '*'.
+// Try inserting an identifier before '*'.
+//   print(*foo);
+//         ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:45:9: Error: Expected an identifier, but got '%'.
+// Try inserting an identifier before '%'.
+//   print(%foo);
+//         ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:46:9: Error: Expected an identifier, but got '|'.
+// Try inserting an identifier before '|'.
+//   print(|foo);
+//         ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:47:9: Error: Expected an identifier, but got '^'.
+// Try inserting an identifier before '^'.
+//   print(^foo);
+//         ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:48:9: Error: Expected an identifier, but got '&'.
+// Try inserting an identifier before '&'.
+//   print(&foo);
+//         ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:49:9: Error: Expected an identifier, but got '<<'.
+// Try inserting an identifier before '<<'.
+//   print(<<foo);
+//         ^^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:50:9: Error: Expected an identifier, but got '>>'.
+// Try inserting an identifier before '>>'.
+//   print(>>foo);
+//         ^^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:54:13: Error: '~' isn't a binary operator.
+//   print(foo ~ 2);
+//             ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:12:13: Error: The operator '<' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   print(foo < 2);
+//             ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:13:13: Error: The operator '>' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '>' operator.
+//   print(foo > 2);
+//             ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:14:13: Error: The operator '<=' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '<=' operator.
+//   print(foo <= 2);
+//             ^^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:15:13: Error: The operator '>=' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '>=' operator.
+//   print(foo >= 2);
+//             ^^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:17:13: Error: The operator '-' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '-' operator.
+//   print(foo - 2);
+//             ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:18:13: Error: The operator '+' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//   print(foo + 2);
+//             ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:19:13: Error: The operator '/' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '/' operator.
+//   print(foo / 2);
+//             ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:20:13: Error: The operator '~/' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '~/' operator.
+//   print(foo ~/ 2);
+//             ^^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:21:13: Error: The operator '*' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '*' operator.
+//   print(foo * 2);
+//             ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:22:13: Error: The operator '%' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '%' operator.
+//   print(foo % 2);
+//             ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:23:13: Error: The operator '|' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '|' operator.
+//   print(foo | 2);
+//             ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:24:13: Error: The operator '^' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '^' operator.
+//   print(foo ^ 2);
+//             ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:25:13: Error: The operator '&' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '&' operator.
+//   print(foo & 2);
+//             ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:26:13: Error: The operator '<<' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '<<' operator.
+//   print(foo << 2);
+//             ^^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:27:13: Error: The operator '>>' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '>>' operator.
+//   print(foo >> 2);
+//             ^^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:29:12: Error: The operator '[]=' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '[]=' operator.
+//   print(foo[2] = 2);
+//            ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:30:12: Error: The operator '[]' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '[]' operator.
+//   print(foo[2]);
+//            ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:31:9: Error: The operator '~' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a '~' operator.
+//   print(~foo);
+//         ^
+//
+// pkg/front_end/testcases/general/operator_method_not_found.dart:32:9: Error: The operator 'unary-' isn't defined for the class 'Foo'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+// Try correcting the operator to an existing operator, or defining a 'unary-' operator.
+//   print(-foo);
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::Foo* foo = new self::Foo::•();
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:12:13: Error: The operator '<' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  print(foo < 2);
+            ^" in foo{<unresolved>}.<(2));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:13:13: Error: The operator '>' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '>' operator.
+  print(foo > 2);
+            ^" in foo{<unresolved>}.>(2));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:14:13: Error: The operator '<=' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '<=' operator.
+  print(foo <= 2);
+            ^^" in foo{<unresolved>}.<=(2));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:15:13: Error: The operator '>=' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '>=' operator.
+  print(foo >= 2);
+            ^^" in foo{<unresolved>}.>=(2));
+  core::print(foo =={self::Foo::==}{(dynamic) →* core::bool*} 2);
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:17:13: Error: The operator '-' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '-' operator.
+  print(foo - 2);
+            ^" in foo{<unresolved>}.-(2));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:18:13: Error: The operator '+' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+  print(foo + 2);
+            ^" in foo{<unresolved>}.+(2));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:19:13: Error: The operator '/' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '/' operator.
+  print(foo / 2);
+            ^" in foo{<unresolved>}./(2));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:20:13: Error: The operator '~/' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '~/' operator.
+  print(foo ~/ 2);
+            ^^" in foo{<unresolved>}.~/(2));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:21:13: Error: The operator '*' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '*' operator.
+  print(foo * 2);
+            ^" in foo{<unresolved>}.*(2));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:22:13: Error: The operator '%' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '%' operator.
+  print(foo % 2);
+            ^" in foo{<unresolved>}.%(2));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:23:13: Error: The operator '|' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '|' operator.
+  print(foo | 2);
+            ^" in foo{<unresolved>}.|(2));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:24:13: Error: The operator '^' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '^' operator.
+  print(foo ^ 2);
+            ^" in foo{<unresolved>}.^(2));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:25:13: Error: The operator '&' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '&' operator.
+  print(foo & 2);
+            ^" in foo{<unresolved>}.&(2));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:26:13: Error: The operator '<<' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '<<' operator.
+  print(foo << 2);
+            ^^" in foo{<unresolved>}.<<(2));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:27:13: Error: The operator '>>' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '>>' operator.
+  print(foo >> 2);
+            ^^" in foo{<unresolved>}.>>(2));
+  core::print(let final self::Foo* #t1 = foo in let final core::int* #t2 = 2 in let final core::int* #t3 = 2 in let final void #t4 = invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:29:12: Error: The operator '[]=' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '[]=' operator.
+  print(foo[2] = 2);
+           ^" in #t1{<unresolved>}.[]=(#t2, #t3) in #t3);
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:30:12: Error: The operator '[]' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '[]' operator.
+  print(foo[2]);
+           ^" in foo{<unresolved>}.[](2));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:31:9: Error: The operator '~' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a '~' operator.
+  print(~foo);
+        ^" in foo{<unresolved>}.~());
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:32:9: Error: The operator 'unary-' isn't defined for the class 'Foo'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/operator_method_not_found.dart'.
+Try correcting the operator to an existing operator, or defining a 'unary-' operator.
+  print(-foo);
+        ^" in foo{<unresolved>}.unary-());
+  core::print(<invalid-type>[]);
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:37:9: Error: This couldn't be parsed.
+  print(>foo);
+        ^"{<invalid>}.>(foo));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:38:9: Error: This couldn't be parsed.
+  print(<=foo);
+        ^"{<invalid>}.<=(foo));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:39:9: Error: This couldn't be parsed.
+  print(>=foo);
+        ^"{<invalid>}.>=(foo));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:40:9: Error: This couldn't be parsed.
+  print(==foo);
+        ^" =={core::Object::==}{(core::Object*) →* core::bool*} foo);
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:41:9: Error: This couldn't be parsed.
+  print(+foo);
+        ^"{<invalid>}.+(foo));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:42:9: Error: This couldn't be parsed.
+  print(/foo);
+        ^"{<invalid>}./(foo));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:43:9: Error: This couldn't be parsed.
+  print(~/foo);
+        ^"{<invalid>}.~/(foo));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:44:9: Error: This couldn't be parsed.
+  print(*foo);
+        ^"{<invalid>}.*(foo));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:45:9: Error: This couldn't be parsed.
+  print(%foo);
+        ^"{<invalid>}.%(foo));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:46:9: Error: This couldn't be parsed.
+  print(|foo);
+        ^"{<invalid>}.|(foo));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:47:9: Error: This couldn't be parsed.
+  print(^foo);
+        ^"{<invalid>}.^(foo));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:48:9: Error: This couldn't be parsed.
+  print(&foo);
+        ^"{<invalid>}.&(foo));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:49:9: Error: This couldn't be parsed.
+  print(<<foo);
+        ^"{<invalid>}.<<(foo));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:50:9: Error: This couldn't be parsed.
+  print(>>foo);
+        ^"{<invalid>}.>>(foo));
+  core::print(invalid-expression "pkg/front_end/testcases/general/operator_method_not_found.dart:54:13: Error: '~' isn't a binary operator.
+  print(foo ~ 2);
+            ^");
+}
diff --git a/pkg/front_end/testcases/general/operators.dart.weak.modular.expect b/pkg/front_end/testcases/general/operators.dart.weak.modular.expect
new file mode 100644
index 0000000..8796e3d4
--- /dev/null
+++ b/pkg/front_end/testcases/general/operators.dart.weak.modular.expect
@@ -0,0 +1,81 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Operators extends core::Object {
+  synthetic constructor •() → self::Operators*
+    : super core::Object::•()
+    ;
+  operator +(dynamic other) → dynamic
+    return null;
+  operator &(dynamic other) → dynamic
+    return null;
+  operator ~() → dynamic
+    return null;
+  operator |(dynamic other) → dynamic
+    return null;
+  operator ^(dynamic other) → dynamic
+    return null;
+  operator /(dynamic other) → dynamic
+    return null;
+  operator ==(dynamic other) → core::bool*
+    return null;
+  operator >(dynamic other) → dynamic
+    return null;
+  operator >=(dynamic other) → dynamic
+    return null;
+  operator [](dynamic index) → dynamic
+    return null;
+  operator []=(dynamic index, dynamic value) → void {}
+  operator <<(dynamic other) → dynamic
+    return null;
+  operator <(dynamic other) → dynamic
+    return null;
+  operator <=(dynamic other) → dynamic
+    return null;
+  operator *(dynamic other) → dynamic
+    return null;
+  operator %(dynamic other) → dynamic
+    return null;
+  operator >>(dynamic other) → dynamic
+    return null;
+  operator -(dynamic other) → dynamic
+    return null;
+  operator ~/(dynamic other) → dynamic
+    return null;
+  operator unary-() → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main(dynamic arguments) → dynamic {
+  self::Operators* a = new self::Operators::•();
+  self::Operators* b = new self::Operators::•();
+  a.{self::Operators::+}(b){(dynamic) →* dynamic};
+  a.{self::Operators::&}(b){(dynamic) →* dynamic};
+  a.{self::Operators::~}(){() →* dynamic};
+  a.{self::Operators::|}(b){(dynamic) →* dynamic};
+  a.{self::Operators::^}(b){(dynamic) →* dynamic};
+  a.{self::Operators::/}(b){(dynamic) →* dynamic};
+  a =={self::Operators::==}{(dynamic) →* core::bool*} b;
+  a.{self::Operators::>}(b){(dynamic) →* dynamic};
+  a.{self::Operators::>=}(b){(dynamic) →* dynamic};
+  a.{self::Operators::[]}(0){(dynamic) →* dynamic};
+  a.{self::Operators::[]=}(0, b){(dynamic, dynamic) →* void};
+  a.{self::Operators::<<}(b){(dynamic) →* dynamic};
+  a.{self::Operators::<}(b){(dynamic) →* dynamic};
+  a.{self::Operators::<=}(b){(dynamic) →* dynamic};
+  a.{self::Operators::*}(b){(dynamic) →* dynamic};
+  a.{self::Operators::%}(b){(dynamic) →* dynamic};
+  a.{self::Operators::>>}(b){(dynamic) →* dynamic};
+  a.{self::Operators::-}(b){(dynamic) →* dynamic};
+  a.{self::Operators::~/}(b){(dynamic) →* dynamic};
+  a.{self::Operators::unary-}(){() →* dynamic};
+}
diff --git a/pkg/front_end/testcases/general/optional.dart.weak.modular.expect b/pkg/front_end/testcases/general/optional.dart.weak.modular.expect
new file mode 100644
index 0000000..6ca451d
--- /dev/null
+++ b/pkg/front_end/testcases/general/optional.dart.weak.modular.expect
@@ -0,0 +1,146 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/optional.dart:47:21: Error: The argument type 'InvalidListener' can't be assigned to the parameter type 'Listener'.
+//  - 'InvalidListener' is from 'pkg/front_end/testcases/general/optional.dart'.
+//  - 'Listener' is from 'pkg/front_end/testcases/general/optional.dart'.
+//   extern.listen(new InvalidListener());
+//                     ^
+//
+// pkg/front_end/testcases/general/optional.dart:49:28: Error: Too few positional arguments: 1 required, 0 given.
+//   var nothing1 = foo.method();
+//                            ^
+//
+// pkg/front_end/testcases/general/optional.dart:50:28: Error: Too many positional arguments: 3 allowed, but 4 found.
+// Try removing the extra positional arguments.
+//   var nothing2 = foo.method(1, 2, 3, 4);
+//                            ^
+//
+// pkg/front_end/testcases/general/optional.dart:51:39: Error: Too few positional arguments: 1 required, 0 given.
+//   var nothing3 = extern.externalMethod();
+//                                       ^
+//
+// pkg/front_end/testcases/general/optional.dart:52:39: Error: Too many positional arguments: 3 allowed, but 4 found.
+// Try removing the extra positional arguments.
+//   var nothing4 = extern.externalMethod(1, 2, 3, 4);
+//                                       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  method method(dynamic x, [dynamic y = #C1, dynamic z = #C1]) → dynamic {
+    return "string";
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class External extends core::Object {
+  synthetic constructor •() → self::External*
+    : super core::Object::•()
+    ;
+  abstract method externalMethod(core::int* x, [core::int* y = #C1, core::int* z = #C1]) → core::String*;
+  abstract method listen(self::Listener* listener) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Listener extends core::Object {
+  synthetic constructor •() → self::Listener*
+    : super core::Object::•()
+    ;
+  abstract method event(core::String* input, [core::int* x = #C1, core::int* y = #C1]) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class TestListener extends self::Listener {
+  synthetic constructor •() → self::TestListener*
+    : super self::Listener::•()
+    ;
+  method event(core::String* input, [core::int* x = #C1, core::int* y = #C1]) → void {}
+}
+class ExtendedListener extends self::Listener {
+  synthetic constructor •() → self::ExtendedListener*
+    : super self::Listener::•()
+    ;
+  method event(core::String* input, [core::int* x = #C1, core::int* y = #C1, dynamic z = #C1]) → void {}
+}
+class InvalidListener extends core::Object {
+  synthetic constructor •() → self::InvalidListener*
+    : super core::Object::•()
+    ;
+  method event(dynamic input, [dynamic x = #C1]) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+external static method createExternal() → self::External*;
+static method main() → dynamic {
+  self::Foo* foo = new self::Foo::•();
+  dynamic string1 = foo.{self::Foo::method}(1){(dynamic, [dynamic, dynamic]) →* dynamic};
+  dynamic string2 = foo.{self::Foo::method}(1, 2){(dynamic, [dynamic, dynamic]) →* dynamic};
+  dynamic string3 = foo.{self::Foo::method}(1, 2, 3){(dynamic, [dynamic, dynamic]) →* dynamic};
+  self::External* extern = self::createExternal();
+  core::String* string4 = extern.{self::External::externalMethod}(1){(core::int*, [core::int*, core::int*]) →* core::String*};
+  core::String* string5 = extern.{self::External::externalMethod}(1, 2){(core::int*, [core::int*, core::int*]) →* core::String*};
+  core::String* string6 = extern.{self::External::externalMethod}(1, 2, 3){(core::int*, [core::int*, core::int*]) →* core::String*};
+  extern.{self::External::listen}(new self::TestListener::•()){(self::Listener*) →* void};
+  extern.{self::External::listen}(new self::ExtendedListener::•()){(self::Listener*) →* void};
+  extern.{self::External::listen}(invalid-expression "pkg/front_end/testcases/general/optional.dart:47:21: Error: The argument type 'InvalidListener' can't be assigned to the parameter type 'Listener'.
+ - 'InvalidListener' is from 'pkg/front_end/testcases/general/optional.dart'.
+ - 'Listener' is from 'pkg/front_end/testcases/general/optional.dart'.
+  extern.listen(new InvalidListener());
+                    ^" in new self::InvalidListener::•() as{TypeError} self::Listener*){(self::Listener*) →* void};
+  invalid-type nothing1 = invalid-expression "pkg/front_end/testcases/general/optional.dart:49:28: Error: Too few positional arguments: 1 required, 0 given.
+  var nothing1 = foo.method();
+                           ^" in foo.{self::Foo::method}{<inapplicable>}.(){() →* invalid-type};
+  invalid-type nothing2 = invalid-expression "pkg/front_end/testcases/general/optional.dart:50:28: Error: Too many positional arguments: 3 allowed, but 4 found.
+Try removing the extra positional arguments.
+  var nothing2 = foo.method(1, 2, 3, 4);
+                           ^" in foo.{self::Foo::method}{<inapplicable>}.(1, 2, 3, 4){(invalid-type, invalid-type, invalid-type, invalid-type) →* invalid-type};
+  invalid-type nothing3 = invalid-expression "pkg/front_end/testcases/general/optional.dart:51:39: Error: Too few positional arguments: 1 required, 0 given.
+  var nothing3 = extern.externalMethod();
+                                      ^" in extern.{self::External::externalMethod}{<inapplicable>}.(){() →* invalid-type};
+  invalid-type nothing4 = invalid-expression "pkg/front_end/testcases/general/optional.dart:52:39: Error: Too many positional arguments: 3 allowed, but 4 found.
+Try removing the extra positional arguments.
+  var nothing4 = extern.externalMethod(1, 2, 3, 4);
+                                      ^" in extern.{self::External::externalMethod}{<inapplicable>}.(1, 2, 3, 4){(invalid-type, invalid-type, invalid-type, invalid-type) →* invalid-type};
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/override.dart.weak.modular.expect b/pkg/front_end/testcases/general/override.dart.weak.modular.expect
new file mode 100644
index 0000000..2ce1243
--- /dev/null
+++ b/pkg/front_end/testcases/general/override.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar extends self::Foo {
+  synthetic constructor •() → self::Bar*
+    : super self::Foo::•()
+    ;
+}
+class Base extends core::Object {
+  synthetic constructor •() → self::Base*
+    : super core::Object::•()
+    ;
+  method method() → self::Foo* {
+    return new self::Foo::•();
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Sub extends self::Base {
+  synthetic constructor •() → self::Sub*
+    : super self::Base::•()
+    ;
+  method method() → self::Foo* {
+    return new self::Bar::•();
+  }
+}
+static method main(core::List<core::String*>* args) → dynamic {
+  self::Base* object = args.{core::List::length}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} 0 ?{self::Base*} new self::Base::•() : new self::Sub::•();
+  self::Foo* a = object.{self::Base::method}(){() →* self::Foo*};
+  core::print(a);
+}
diff --git a/pkg/front_end/testcases/general/override_check_accessor_after_inference.dart.weak.modular.expect b/pkg/front_end/testcases/general/override_check_accessor_after_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..181c1db
--- /dev/null
+++ b/pkg/front_end/testcases/general/override_check_accessor_after_inference.dart.weak.modular.expect
@@ -0,0 +1,90 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/override_check_accessor_after_inference.dart:26:9: Error: The return type of the method 'F.y' is 'A', which does not match the return type, 'B', of the overridden method, 'D.y'.
+//  - 'A' is from 'pkg/front_end/testcases/general/override_check_accessor_after_inference.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/general/override_check_accessor_after_inference.dart'.
+// Change to a subtype of 'B'.
+//   A get y => null;
+//         ^
+// pkg/front_end/testcases/general/override_check_accessor_after_inference.dart:16:7: Context: This is the overridden method ('y').
+//   get y => null; // Inferred type: B
+//       ^
+//
+// pkg/front_end/testcases/general/override_check_accessor_after_inference.dart:25:16: Error: The parameter 'value' of the method 'F.x' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'D.x'.
+//  - 'B' is from 'pkg/front_end/testcases/general/override_check_accessor_after_inference.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/override_check_accessor_after_inference.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   void set x(B value) {}
+//                ^
+// pkg/front_end/testcases/general/override_check_accessor_after_inference.dart:15:12: Context: This is the overridden method ('x').
+//   void set x(value) {} // Inferred type: A
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  set x(self::A* value) → void {}
+  get y() → self::B*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  set x(self::A* value) → void {}
+  get y() → self::B*
+    return null;
+}
+class E extends self::D {
+  synthetic constructor •() → self::E*
+    : super self::D::•()
+    ;
+  set x(self::A* value) → void {}
+  get y() → self::B*
+    return null;
+}
+class F extends self::D {
+  synthetic constructor •() → self::F*
+    : super self::D::•()
+    ;
+  set x(self::B* value) → void {}
+  get y() → self::A*
+    return null;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/override_check_accessor_basic.dart.weak.modular.expect b/pkg/front_end/testcases/general/override_check_accessor_basic.dart.weak.modular.expect
new file mode 100644
index 0000000..d576b70
--- /dev/null
+++ b/pkg/front_end/testcases/general/override_check_accessor_basic.dart.weak.modular.expect
@@ -0,0 +1,82 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/override_check_accessor_basic.dart:21:14: Error: The return type of the method 'E.y' is 'Object', which does not match the return type, 'A', of the overridden method, 'C.y'.
+//  - 'Object' is from 'dart:core'.
+//  - 'A' is from 'pkg/front_end/testcases/general/override_check_accessor_basic.dart'.
+// Change to a subtype of 'A'.
+//   Object get y => null;
+//              ^
+// pkg/front_end/testcases/general/override_check_accessor_basic.dart:11:9: Context: This is the overridden method ('y').
+//   A get y => null;
+//         ^
+//
+// pkg/front_end/testcases/general/override_check_accessor_basic.dart:20:16: Error: The parameter 'value' of the method 'E.x' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'C.x'.
+//  - 'B' is from 'pkg/front_end/testcases/general/override_check_accessor_basic.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/override_check_accessor_basic.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   void set x(B value) {}
+//                ^
+// pkg/front_end/testcases/general/override_check_accessor_basic.dart:10:12: Context: This is the overridden method ('x').
+//   void set x(A value) {}
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  set x(self::A* value) → void {}
+  get y() → self::A*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  set x(core::Object* value) → void {}
+  get y() → self::B*
+    return null;
+}
+class E extends self::C {
+  synthetic constructor •() → self::E*
+    : super self::C::•()
+    ;
+  set x(self::B* value) → void {}
+  get y() → core::Object*
+    return null;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/override_check_accessor_with_covariant_modifier.dart.weak.modular.expect b/pkg/front_end/testcases/general/override_check_accessor_with_covariant_modifier.dart.weak.modular.expect
new file mode 100644
index 0000000..14fa421
--- /dev/null
+++ b/pkg/front_end/testcases/general/override_check_accessor_with_covariant_modifier.dart.weak.modular.expect
@@ -0,0 +1,79 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/override_check_accessor_with_covariant_modifier.dart:22:17: Error: The parameter 'value' of the method 'D.x4' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'C.x4'.
+//  - 'B' is from 'pkg/front_end/testcases/general/override_check_accessor_with_covariant_modifier.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/override_check_accessor_with_covariant_modifier.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   void set x4(B value) {} // Not covariant
+//                 ^
+// pkg/front_end/testcases/general/override_check_accessor_with_covariant_modifier.dart:13:12: Context: This is the overridden method ('x4').
+//   void set x4(A value) {}
+//            ^
+//
+// pkg/front_end/testcases/general/override_check_accessor_with_covariant_modifier.dart:23:32: Error: The parameter 'value' of the method 'D.x5' has type 'String', which does not match the corresponding type, 'A', in the overridden method, 'C.x5'.
+//  - 'A' is from 'pkg/front_end/testcases/general/override_check_accessor_with_covariant_modifier.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   void set x5(covariant String value) {}
+//                                ^
+// pkg/front_end/testcases/general/override_check_accessor_with_covariant_modifier.dart:14:12: Context: This is the overridden method ('x5').
+//   void set x5(covariant A value) {}
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  set x1(covariant-by-declaration self::A* value) → void {}
+  set x2(self::A* value) → void {}
+  set x3(covariant-by-declaration self::A* value) → void {}
+  set x4(self::A* value) → void {}
+  set x5(covariant-by-declaration self::A* value) → void {}
+  set x6(covariant-by-declaration self::B* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  set x1(covariant-by-declaration self::B* value) → void {}
+  set x2(covariant-by-declaration self::B* value) → void {}
+  set x3(covariant-by-declaration self::B* value) → void {}
+  set x4(self::B* value) → void {}
+  set x5(covariant-by-declaration core::String* value) → void {}
+  set x6(covariant-by-declaration self::A* value) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/override_check_after_inference.dart.weak.modular.expect b/pkg/front_end/testcases/general/override_check_after_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..f6a987f
--- /dev/null
+++ b/pkg/front_end/testcases/general/override_check_after_inference.dart.weak.modular.expect
@@ -0,0 +1,72 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/override_check_after_inference.dart:22:12: Error: The parameter 'x' of the method 'F.f' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'D.f'.
+//  - 'B' is from 'pkg/front_end/testcases/general/override_check_after_inference.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/override_check_after_inference.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   void f(B x) {}
+//            ^
+// pkg/front_end/testcases/general/override_check_after_inference.dart:14:8: Context: This is the overridden method ('f').
+//   void f(x) {} // Inferred type: (A) -> void
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f(self::A* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method f(self::A* x) → void {}
+}
+class E extends self::D {
+  synthetic constructor •() → self::E*
+    : super self::D::•()
+    ;
+  method f(self::A* x) → void {}
+}
+class F extends self::D {
+  synthetic constructor •() → self::F*
+    : super self::D::•()
+    ;
+  method f(self::B* x) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/override_check_basic.dart.weak.modular.expect b/pkg/front_end/testcases/general/override_check_basic.dart.weak.modular.expect
new file mode 100644
index 0000000..e19c0a4
--- /dev/null
+++ b/pkg/front_end/testcases/general/override_check_basic.dart.weak.modular.expect
@@ -0,0 +1,109 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/override_check_basic.dart:24:13: Error: The parameter 'x' of the method 'E.f1' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'C.f1'.
+//  - 'B' is from 'pkg/front_end/testcases/general/override_check_basic.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/override_check_basic.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   void f1(B x) {}
+//             ^
+// pkg/front_end/testcases/general/override_check_basic.dart:10:8: Context: This is the overridden method ('f1').
+//   void f1(A x) {}
+//        ^
+//
+// pkg/front_end/testcases/general/override_check_basic.dart:25:14: Error: The parameter 'x' of the method 'E.f2' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'C.f2'.
+//  - 'B' is from 'pkg/front_end/testcases/general/override_check_basic.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/override_check_basic.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   void f2([B x]) {}
+//              ^
+// pkg/front_end/testcases/general/override_check_basic.dart:11:8: Context: This is the overridden method ('f2').
+//   void f2([A x]) {}
+//        ^
+//
+// pkg/front_end/testcases/general/override_check_basic.dart:26:14: Error: The parameter 'x' of the method 'E.f3' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'C.f3'.
+//  - 'B' is from 'pkg/front_end/testcases/general/override_check_basic.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/override_check_basic.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   void f3({B x}) {}
+//              ^
+// pkg/front_end/testcases/general/override_check_basic.dart:12:8: Context: This is the overridden method ('f3').
+//   void f3({A x}) {}
+//        ^
+//
+// pkg/front_end/testcases/general/override_check_basic.dart:27:10: Error: The return type of the method 'E.f4' is 'Object', which does not match the return type, 'A', of the overridden method, 'C.f4'.
+//  - 'Object' is from 'dart:core'.
+//  - 'A' is from 'pkg/front_end/testcases/general/override_check_basic.dart'.
+// Change to a subtype of 'A'.
+//   Object f4() {}
+//          ^
+// pkg/front_end/testcases/general/override_check_basic.dart:13:5: Context: This is the overridden method ('f4').
+//   A f4() {}
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f1(self::A* x) → void {}
+  method f2([self::A* x = #C1]) → void {}
+  method f3({self::A* x = #C1}) → void {}
+  method f4() → self::A* {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method f1(core::Object* x) → void {}
+  method f2([core::Object* x = #C1]) → void {}
+  method f3({core::Object* x = #C1}) → void {}
+  method f4() → self::B* {}
+}
+class E extends self::C {
+  synthetic constructor •() → self::E*
+    : super self::C::•()
+    ;
+  method f1(self::B* x) → void {}
+  method f2([self::B* x = #C1]) → void {}
+  method f3({self::B* x = #C1}) → void {}
+  method f4() → core::Object* {}
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/override_check_generic_method_f_bounded.dart.weak.modular.expect b/pkg/front_end/testcases/general/override_check_generic_method_f_bounded.dart.weak.modular.expect
new file mode 100644
index 0000000..ed9f7b4
--- /dev/null
+++ b/pkg/front_end/testcases/general/override_check_generic_method_f_bounded.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Foo<T extends self::Foo<self::Foo::T*>* = self::Foo<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::Foo<self::Foo::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Bar extends core::Object {
+  synthetic constructor •() → self::Bar*
+    : super core::Object::•()
+    ;
+  abstract method fisk<S extends self::Foo<self::Bar::fisk::S*>* = self::Foo<dynamic>*>() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Hest extends core::Object implements self::Bar {
+  synthetic constructor •() → self::Hest*
+    : super core::Object::•()
+    ;
+  @#C1
+  method fisk<U extends self::Foo<self::Hest::fisk::U*>* = self::Foo<dynamic>*>() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {}
+
+constants  {
+  #C1 = core::_Override {}
+}
diff --git a/pkg/front_end/testcases/general/override_check_two_substitutions.dart.weak.modular.expect b/pkg/front_end/testcases/general/override_check_two_substitutions.dart.weak.modular.expect
new file mode 100644
index 0000000..54a4764
--- /dev/null
+++ b/pkg/front_end/testcases/general/override_check_two_substitutions.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  method f<U extends core::Object* = dynamic>(covariant-by-class core::Map<self::A::T*, self::A::f::U*>* m) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A<core::String*> {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  method f<V extends core::Object* = dynamic>(covariant-by-class core::Map<core::String*, self::B::f::V*>* m) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/override_check_with_covariant_modifier.dart.weak.modular.expect b/pkg/front_end/testcases/general/override_check_with_covariant_modifier.dart.weak.modular.expect
new file mode 100644
index 0000000..ceabd22
--- /dev/null
+++ b/pkg/front_end/testcases/general/override_check_with_covariant_modifier.dart.weak.modular.expect
@@ -0,0 +1,79 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/override_check_with_covariant_modifier.dart:22:13: Error: The parameter 'x' of the method 'D.f4' has type 'B', which does not match the corresponding type, 'A', in the overridden method, 'C.f4'.
+//  - 'B' is from 'pkg/front_end/testcases/general/override_check_with_covariant_modifier.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/general/override_check_with_covariant_modifier.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   void f4(B x) {} // Not covariant
+//             ^
+// pkg/front_end/testcases/general/override_check_with_covariant_modifier.dart:13:8: Context: This is the overridden method ('f4').
+//   void f4(A x) {}
+//        ^
+//
+// pkg/front_end/testcases/general/override_check_with_covariant_modifier.dart:23:28: Error: The parameter 'x' of the method 'D.f5' has type 'String', which does not match the corresponding type, 'A', in the overridden method, 'C.f5'.
+//  - 'A' is from 'pkg/front_end/testcases/general/override_check_with_covariant_modifier.dart'.
+// Change to a supertype of 'A', or, for a covariant parameter, a subtype.
+//   void f5(covariant String x) {}
+//                            ^
+// pkg/front_end/testcases/general/override_check_with_covariant_modifier.dart:14:8: Context: This is the overridden method ('f5').
+//   void f5(covariant A x) {}
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f1(covariant-by-declaration self::A* x) → void {}
+  method f2(self::A* x) → void {}
+  method f3(covariant-by-declaration self::A* x) → void {}
+  method f4(self::A* x) → void {}
+  method f5(covariant-by-declaration self::A* x) → void {}
+  method f6(covariant-by-declaration self::B* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method f1(covariant-by-declaration self::B* x) → void {}
+  method f2(covariant-by-declaration self::B* x) → void {}
+  method f3(covariant-by-declaration self::B* x) → void {}
+  method f4(self::B* x) → void {}
+  method f5(covariant-by-declaration core::String* x) → void {}
+  method f6(covariant-by-declaration self::A* x) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/override_inference_for_getters_and_setters.dart.weak.modular.expect b/pkg/front_end/testcases/general/override_inference_for_getters_and_setters.dart.weak.modular.expect
new file mode 100644
index 0000000..a188410
--- /dev/null
+++ b/pkg/front_end/testcases/general/override_inference_for_getters_and_setters.dart.weak.modular.expect
@@ -0,0 +1,117 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract get getterFromGetter() → core::num*;
+  abstract set setterFromSetter(core::num* value) → void;
+  abstract set getterFromSetter(core::num* value) → void;
+  abstract get setterFromGetter() → core::num*;
+  abstract get getterFromGetterWithSetterConflict() → core::num*;
+  abstract set getterFromGetterWithSetterConflict(dynamic num) → void;
+  abstract get setterFromSetterWithGetterConflict() → core::num*;
+  abstract set setterFromSetterWithGetterConflict(dynamic num) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract get getterFromGetter() → core::int*;
+  abstract set setterFromSetter(core::int* value) → void;
+  abstract get setterFromGetter() → core::int*;
+  abstract get setterFromSetterWithGetterConflict() → core::int*;
+  abstract set getterFromGetterWithSetterConflict(core::int* value) → void;
+  abstract set getterFromSetter(core::int* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends self::A {
+  synthetic constructor •() → self::C*
+    : super self::A::•()
+    ;
+  abstract get getterFromGetter() → core::num*;
+  abstract set setterFromSetter(core::num* value) → void;
+  abstract get getterFromSetter() → core::num*;
+  abstract set setterFromGetter(core::num* value) → void;
+  abstract get getterFromGetterWithSetterConflict() → core::num*;
+  abstract set setterFromSetterWithGetterConflict(dynamic value) → void;
+}
+abstract class D extends self::A implements self::B {
+  synthetic constructor •() → self::D*
+    : super self::A::•()
+    ;
+  abstract get getterFromGetter() → core::int*;
+  abstract set setterFromSetter(core::num* value) → void;
+  abstract get getterFromSetter() → core::num*;
+  abstract set setterFromGetter(core::int* value) → void;
+  abstract get getterFromGetterWithSetterConflict() → core::num*;
+  abstract set setterFromSetterWithGetterConflict(dynamic value) → void;
+  abstract member-signature get setterFromGetter() → core::int*; -> self::B::setterFromGetter
+  abstract member-signature get setterFromSetterWithGetterConflict() → core::int*; -> self::B::setterFromSetterWithGetterConflict
+}
+abstract class E extends core::Object implements self::A {
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  abstract get getterFromGetter() → core::num*;
+  abstract set setterFromSetter(core::num* value) → void;
+  abstract get getterFromSetter() → core::num*;
+  abstract set setterFromGetter(core::num* value) → void;
+  abstract get getterFromGetterWithSetterConflict() → core::num*;
+  abstract set setterFromSetterWithGetterConflict(dynamic value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class F extends core::Object implements self::A, self::B {
+  synthetic constructor •() → self::F*
+    : super core::Object::•()
+    ;
+  abstract get getterFromGetter() → core::int*;
+  abstract set setterFromSetter(core::num* value) → void;
+  abstract get getterFromSetter() → core::num*;
+  abstract set setterFromGetter(core::int* value) → void;
+  abstract get getterFromGetterWithSetterConflict() → core::num*;
+  abstract set setterFromSetterWithGetterConflict(dynamic value) → void;
+  abstract member-signature get setterFromGetter() → core::int*; -> self::B::setterFromGetter
+  abstract member-signature get setterFromSetterWithGetterConflict() → core::int*; -> self::B::setterFromSetterWithGetterConflict
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/override_inference_for_setters.dart.weak.modular.expect b/pkg/front_end/testcases/general/override_inference_for_setters.dart.weak.modular.expect
new file mode 100644
index 0000000..845e3fb
--- /dev/null
+++ b/pkg/front_end/testcases/general/override_inference_for_setters.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  get foo() → core::num*
+    return null;
+  set foo(dynamic newFoo) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends self::B {
+  synthetic constructor •() → self::A*
+    : super self::B::•()
+    ;
+  set foo(dynamic newFoo) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/override_inference_named_parameters_ordering.dart.weak.modular.expect b/pkg/front_end/testcases/general/override_inference_named_parameters_ordering.dart.weak.modular.expect
new file mode 100644
index 0000000..6e67b60
--- /dev/null
+++ b/pkg/front_end/testcases/general/override_inference_named_parameters_ordering.dart.weak.modular.expect
@@ -0,0 +1,66 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method foo({core::bool* c = #C1, core::bool* a = #C2}) → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  method foo({core::bool* c = #C1, core::bool* a = #C2}) → dynamic {}
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  method foo({core::bool* c = #C1, core::bool* a = #C2}) → dynamic {}
+}
+class A1 extends core::Object {
+  synthetic constructor •() → self::A1*
+    : super core::Object::•()
+    ;
+  method foo({core::bool* a = #C1, core::bool* c = #C2}) → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B1 extends self::A1 {
+  synthetic constructor •() → self::B1*
+    : super self::A1::•()
+    ;
+  method foo({core::bool* a = #C1, core::bool* c = #C2}) → dynamic {}
+}
+class C1 extends self::B1 {
+  synthetic constructor •() → self::C1*
+    : super self::B1::•()
+    ;
+  method foo({core::bool* a = #C1, core::bool* c = #C2}) → dynamic {}
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = true
+  #C2 = null
+}
diff --git a/pkg/front_end/testcases/general/override_setter_with_field.dart.weak.modular.expect b/pkg/front_end/testcases/general/override_setter_with_field.dart.weak.modular.expect
new file mode 100644
index 0000000..765d23f
--- /dev/null
+++ b/pkg/front_end/testcases/general/override_setter_with_field.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/override_setter_with_field.dart:12:7: Error: The field 'B.x' has type 'int', which does not match the corresponding type, 'Object', in the overridden setter, 'A.x'.
+//  - 'Object' is from 'dart:core'.
+//   int x;
+//       ^
+// pkg/front_end/testcases/general/override_setter_with_field.dart:8:12: Context: This is the overridden method ('x').
+//   void set x(Object y);
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract set x(core::Object* y) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::A {
+  field core::int* x = null;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::B::•().{self::B::x} = 5;
+}
diff --git a/pkg/front_end/testcases/general/part_as_entry_point.dart.weak.modular.expect b/pkg/front_end/testcases/general/part_as_entry_point.dart.weak.modular.expect
new file mode 100644
index 0000000..b77b0c2
--- /dev/null
+++ b/pkg/front_end/testcases/general/part_as_entry_point.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+part part_as_entry_point.dart;
+static method main() → dynamic {
+  core::print("Hello, World!");
+}
diff --git a/pkg/front_end/testcases/general/part_not_part_of.dart.weak.modular.expect b/pkg/front_end/testcases/general/part_not_part_of.dart.weak.modular.expect
new file mode 100644
index 0000000..f22e87e
--- /dev/null
+++ b/pkg/front_end/testcases/general/part_not_part_of.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/part_not_part_of.dart:8:6: Error: Can't use 'pkg/front_end/testcases/general/part_not_part_of_lib1.dart' as a part, because it has no 'part of' declaration.
+// part 'part_not_part_of_lib1.dart';
+//      ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///part_not_part_of_lib2.dart";
+
+@#C1
+part part_not_part_of_lib1.dart;
+static method main() → dynamic {}
+
+library;
+import self as self2;
+import "part_not_part_of_lib1.dart" as par;
+
+import "org-dartlang-testcase:///part_not_part_of_lib1.dart";
+
+static method methodFromLib2() → dynamic {
+  par::methodFromLib1();
+}
+
+library;
+import self as par;
+
+static method methodFromLib1() → dynamic {}
+
+constants  {
+  #C1 = core::_Override {}
+}
diff --git a/pkg/front_end/testcases/general/part_not_part_of_same_named_library.dart.weak.modular.expect b/pkg/front_end/testcases/general/part_not_part_of_same_named_library.dart.weak.modular.expect
new file mode 100644
index 0000000..2048308
--- /dev/null
+++ b/pkg/front_end/testcases/general/part_not_part_of_same_named_library.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/part_not_part_of_same_named_library.dart:8:6: Error: Using 'pkg/front_end/testcases/general/part_not_part_of_same_named_library_lib1.dart' as part of 'pkg/front_end/testcases/general/part_not_part_of_same_named_library.dart' but its 'part of' declaration says 'foo'.
+// Try changing the 'part of' declaration to use a relative file name.
+// part 'part_not_part_of_same_named_library_lib1.dart';
+//      ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///part_not_part_of_same_named_library_lib2.dart";
+
+@#C1
+part part_not_part_of_same_named_library_lib1.dart;
+static method main() → dynamic {}
+
+library foo;
+import self as self2;
+
+part part_not_part_of_same_named_library_lib1.dart;
+static method /* from org-dartlang-testcase:///part_not_part_of_same_named_library_lib1.dart */ methodFromLib1() → dynamic {}
+static method methodFromLib2() → dynamic {
+  self2::methodFromLib1();
+}
+
+constants  {
+  #C1 = core::_Override {}
+}
diff --git a/pkg/front_end/testcases/general/part_part_of_different_unnamed_library.dart.weak.modular.expect b/pkg/front_end/testcases/general/part_part_of_different_unnamed_library.dart.weak.modular.expect
new file mode 100644
index 0000000..693c671
--- /dev/null
+++ b/pkg/front_end/testcases/general/part_part_of_different_unnamed_library.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/part_part_of_different_unnamed_library.dart:8:6: Error: Using 'pkg/front_end/testcases/general/part_part_of_different_unnamed_library_lib1.dart' as part of 'pkg/front_end/testcases/general/part_part_of_different_unnamed_library.dart' but its 'part of' declaration says 'pkg/front_end/testcases/general/part_part_of_different_unnamed_library_lib2.dart'.
+// part 'part_part_of_different_unnamed_library_lib1.dart';
+//      ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///part_part_of_different_unnamed_library_lib2.dart";
+
+@#C1
+part part_part_of_different_unnamed_library_lib1.dart;
+static method main() → dynamic {}
+
+library;
+import self as self2;
+
+part part_part_of_different_unnamed_library_lib1.dart;
+static method /* from org-dartlang-testcase:///part_part_of_different_unnamed_library_lib1.dart */ methodFromLib1() → dynamic {}
+static method methodFromLib2() → dynamic {
+  self2::methodFromLib1();
+}
+
+constants  {
+  #C1 = core::_Override {}
+}
diff --git a/pkg/front_end/testcases/general/part_part_of_differently_named_library.dart.weak.modular.expect b/pkg/front_end/testcases/general/part_part_of_differently_named_library.dart.weak.modular.expect
new file mode 100644
index 0000000..0ec56bd
--- /dev/null
+++ b/pkg/front_end/testcases/general/part_part_of_differently_named_library.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library foo;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/part_part_of_differently_named_library.dart:10:6: Error: Using 'pkg/front_end/testcases/general/part_part_of_differently_named_library_lib1.dart' as part of 'foo' but its 'part of' declaration says 'bar'.
+// part 'part_part_of_differently_named_library_lib1.dart';
+//      ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///part_part_of_differently_named_library_lib2.dart";
+
+@#C1
+part part_part_of_differently_named_library_lib1.dart;
+static method main() → dynamic {}
+
+library bar;
+import self as self2;
+
+part part_part_of_differently_named_library_lib1.dart;
+static method /* from org-dartlang-testcase:///part_part_of_differently_named_library_lib1.dart */ methodFromLib1() → dynamic {}
+static method methodFromLib2() → dynamic {
+  self2::methodFromLib1();
+}
+
+constants  {
+  #C1 = core::_Override {}
+}
diff --git a/pkg/front_end/testcases/general/platform.dart.weak.modular.expect b/pkg/front_end/testcases/general/platform.dart.weak.modular.expect
new file mode 100644
index 0000000..bef6d48
--- /dev/null
+++ b/pkg/front_end/testcases/general/platform.dart.weak.modular.expect
@@ -0,0 +1,4 @@
+library;
+import self as self;
+
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/platform_invalid_uris/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/platform_invalid_uris/main.dart.weak.modular.expect
new file mode 100644
index 0000000..fa5d4ba
--- /dev/null
+++ b/pkg/front_end/testcases/general/platform_invalid_uris/main.dart.weak.modular.expect
@@ -0,0 +1,108 @@
+library;
+import self as self;
+import "dart:test" as test;
+
+import "dart:test";
+
+static method main() → dynamic {
+  new test::Class::•();
+}
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/platform_invalid_uris/patch_lib.dart:8:9: Error: Couldn't parse URI ':c':
+//   Invalid empty scheme.
+// import ':c';
+//         ^
+//
+// pkg/front_end/testcases/general/platform_invalid_uris/patch_lib.dart:9:9: Error: Couldn't parse URI ':d':
+//   Invalid empty scheme.
+// export ':d';
+//         ^
+//
+// pkg/front_end/testcases/general/platform_invalid_uris/origin_lib.dart:5:9: Error: Couldn't parse URI ':a':
+//   Invalid empty scheme.
+// import ':a';
+//         ^
+//
+// pkg/front_end/testcases/general/platform_invalid_uris/origin_lib.dart:6:9: Error: Couldn't parse URI ':b':
+//   Invalid empty scheme.
+// export ':b';
+//         ^
+//
+import self as test;
+import "dart:_internal" as _in;
+import "dart:core" as core;
+
+import "dart:_internal";
+import "org-dartlang-malformed-uri:?%3Ac";
+export "org-dartlang-malformed-uri:?%3Ad";
+import "org-dartlang-malformed-uri:?%3Aa";
+export "org-dartlang-malformed-uri:?%3Ab";
+
+@#C1
+class Class extends core::Object {
+  synthetic constructor •() → test::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/platform_invalid_uris/patch_lib.dart:8:8: Error: Expected a URI.
+// import ':c';
+//        ^
+//
+import self as self2;
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/platform_invalid_uris/patch_lib.dart:9:1: Error: Expected a URI.
+// export ':d';
+// ^
+//
+import self as self3;
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/platform_invalid_uris/origin_lib.dart:5:8: Error: Expected a URI.
+// import ':a';
+//        ^
+//
+import self as self4;
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/platform_invalid_uris/origin_lib.dart:6:1: Error: Expected a URI.
+// export ':b';
+// ^
+//
+import self as self5;
+
+
+constants  {
+  #C1 = _in::_Patch {}
+}
diff --git a/pkg/front_end/testcases/general/prefer_baseclass.dart.weak.modular.expect b/pkg/front_end/testcases/general/prefer_baseclass.dart.weak.modular.expect
new file mode 100644
index 0000000..8785424
--- /dev/null
+++ b/pkg/front_end/testcases/general/prefer_baseclass.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class AB1 extends self::A implements self::B {
+  synthetic constructor •() → self::AB1*
+    : super self::A::•()
+    ;
+}
+class AB2 extends self::A implements self::B {
+  synthetic constructor •() → self::AB2*
+    : super self::A::•()
+    ;
+}
+class BA1 extends self::B implements self::A {
+  synthetic constructor •() → self::BA1*
+    : super self::B::•()
+    ;
+}
+class BA2 extends self::B implements self::A {
+  synthetic constructor •() → self::BA2*
+    : super self::B::•()
+    ;
+}
+static method takeSubclassOfA(dynamic obj) → dynamic {}
+static method takeSubclassOfB(dynamic obj) → dynamic {}
+static method main() → dynamic {
+  self::takeSubclassOfA(new self::AB1::•());
+  self::takeSubclassOfA(new self::AB2::•());
+  self::takeSubclassOfB(new self::BA1::•());
+  self::takeSubclassOfB(new self::BA2::•());
+}
diff --git a/pkg/front_end/testcases/general/private_members.dart.weak.modular.expect b/pkg/front_end/testcases/general/private_members.dart.weak.modular.expect
new file mode 100644
index 0000000..7d67ee2
--- /dev/null
+++ b/pkg/front_end/testcases/general/private_members.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+part private_members_part.dart;
+abstract class _AbstractClass extends core::Object { // from org-dartlang-testcase:///private_members_part.dart
+  synthetic constructor •() → self::_AbstractClass
+    : super core::Object::•()
+    ;
+  abstract get _privateAbstractField() → core::int;
+  abstract set _privateAbstractField(core::int #externalFieldValue) → void;
+}
+class _Class extends core::Object { // from org-dartlang-testcase:///private_members_part.dart
+  field core::int _privateField = 1;
+  field core::int _privateFinalField = 1;
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor _privateConstructor() → self::_Class
+    : super core::Object::•()
+    ;
+  static factory _privateRedirectingFactory() → self::_Class
+    return new self::_Class::_privateConstructor();
+  method _privateMethod() → void {}
+  get _privateGetter() → core::int
+    return 42;
+  set _privateSetter(core::int value) → void {}
+}
+extension _Extension on core::int { // from org-dartlang-testcase:///private_members_part.dart
+  method _privateMethod = self::_Extension|_privateMethod;
+  tearoff _privateMethod = self::_Extension|get#_privateMethod;
+  get _privateGetter = self::_Extension|get#_privateGetter;
+  static field _privateField = self::_Extension|_privateField;
+  static field _privateFinalField = self::_Extension|_privateFinalField;
+  set _privateSetter = self::_Extension|set#_privateSetter;
+}
+static field core::int _Extension|_privateField = 1 /* from org-dartlang-testcase:///private_members_part.dart */;
+static field core::int _Extension|_privateFinalField = 1 /* from org-dartlang-testcase:///private_members_part.dart */;
+static method test(self::_AbstractClass c) → dynamic {
+  c.{self::_AbstractClass::_privateAbstractField} = c.{self::_AbstractClass::_privateAbstractField}{core::int};
+}
+static method main() → dynamic {
+  self::_Class c = new self::_Class::_privateConstructor();
+  c = new self::_Class::_privateConstructor();
+  c.{self::_Class::_privateMethod}(){() → void};
+  c.{self::_Class::_privateSetter} = c.{self::_Class::_privateGetter}{core::int};
+  c.{self::_Class::_privateField} = c.{self::_Class::_privateField}{core::int};
+  c.{self::_Class::_privateFinalField}{core::int};
+  self::_Extension|_privateMethod(0);
+  self::_Extension|get#_privateMethod(0)(){() → void};
+  self::_Extension|set#_privateSetter(0, self::_Extension|get#_privateGetter(0));
+  self::_Extension|_privateField = self::_Extension|_privateField;
+  self::_Extension|_privateFinalField;
+}
+static method /* from org-dartlang-testcase:///private_members_part.dart */ _Extension|_privateMethod(lowered final core::int #this) → void {}
+static method /* from org-dartlang-testcase:///private_members_part.dart */ _Extension|get#_privateMethod(lowered final core::int #this) → () → void
+  return () → void => self::_Extension|_privateMethod(#this);
+static method /* from org-dartlang-testcase:///private_members_part.dart */ _Extension|get#_privateGetter(lowered final core::int #this) → core::int
+  return 42;
+static method /* from org-dartlang-testcase:///private_members_part.dart */ _Extension|set#_privateSetter(lowered final core::int #this, core::int value) → void {}
+
+constants  {
+  #C1 = constructor-tearoff self::_Class::_privateRedirectingFactory
+}
diff --git a/pkg/front_end/testcases/general/private_method_tearoff.dart.weak.modular.expect b/pkg/front_end/testcases/general/private_method_tearoff.dart.weak.modular.expect
new file mode 100644
index 0000000..ca1fea0
--- /dev/null
+++ b/pkg/front_end/testcases/general/private_method_tearoff.dart.weak.modular.expect
@@ -0,0 +1,63 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "private_method_tearoff_lib.dart" as pri;
+
+import "org-dartlang-testcase:///private_method_tearoff_lib.dart";
+
+class Foo extends core::Object implements pri::Bar {
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method /* from org-dartlang-testcase:///private_method_tearoff_lib.dart */ _f() → void
+    return this.{self::Foo::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+class Baz extends self::Foo {
+  synthetic constructor •() → self::Baz*
+    : super self::Foo::•()
+    ;
+}
+static method main() → dynamic {
+  pri::baz(new self::Foo::•());
+}
+
+library;
+import self as pri;
+import "dart:core" as core;
+
+class Bar extends core::Object {
+  synthetic constructor •() → pri::Bar*
+    : super core::Object::•()
+    ;
+  method _f() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method baz(pri::Bar* bar) → void {
+  core::print("${bar.{pri::Bar::_f}{() →* void}.{core::Object::runtimeType}{core::Type*}}");
+}
+
+constants  {
+  #C1 = #org-dartlang-testcase:///private_method_tearoff.dart::_f
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/general/promoted_access.dart.weak.modular.expect b/pkg/front_end/testcases/general/promoted_access.dart.weak.modular.expect
new file mode 100644
index 0000000..7439751
--- /dev/null
+++ b/pkg/front_end/testcases/general/promoted_access.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::T*>*
+    : super core::Object::•()
+    ;
+  method method(covariant-by-class self::Class::T* o) → dynamic {
+    if(o is self::Class<dynamic>*) {
+      o{self::Class::T* & self::Class<dynamic>* /* '*' & '*' = '*' */}.{self::Class::method}(null){(dynamic) →* dynamic};
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method method<T extends core::Object* = dynamic>(self::method::T* o) → dynamic {
+  if(o is self::Class<dynamic>*) {
+    o{self::method::T* & self::Class<dynamic>* /* '*' & '*' = '*' */}.{self::Class::method}(null){(dynamic) →* dynamic};
+  }
+}
+static method main() → dynamic {
+  new self::Class::•<dynamic>().{self::Class::method}(new self::Class::•<dynamic>()){(dynamic) →* dynamic};
+  self::method<self::Class<dynamic>*>(new self::Class::•<dynamic>());
+}
diff --git a/pkg/front_end/testcases/general/promoted_null_aware_access.dart.weak.modular.expect b/pkg/front_end/testcases/general/promoted_null_aware_access.dart.weak.modular.expect
new file mode 100644
index 0000000..09affa3
--- /dev/null
+++ b/pkg/front_end/testcases/general/promoted_null_aware_access.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method method<T extends core::Object* = dynamic>(self::method::T* o) → dynamic {
+  if(o is core::String*) {
+    let final self::method::T* & core::String* /* '*' & '*' = '*' */ #t1 = o{self::method::T* & core::String* /* '*' & '*' = '*' */} in #t1 == null ?{core::int*} null : #t1.{core::String::length}{core::int*};
+  }
+}
+static method main() → dynamic {
+  self::method<core::String*>("");
+}
diff --git a/pkg/front_end/testcases/general/public_method_tearoff.dart.weak.modular.expect b/pkg/front_end/testcases/general/public_method_tearoff.dart.weak.modular.expect
new file mode 100644
index 0000000..6fc1a72
--- /dev/null
+++ b/pkg/front_end/testcases/general/public_method_tearoff.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library;
+import self as self;
+import "public_method_tearoff_lib.dart" as pub;
+
+import "org-dartlang-testcase:///public_method_tearoff_lib.dart";
+
+class Foo extends pub::Bar {
+  synthetic constructor •() → self::Foo*
+    : super pub::Bar::•()
+    ;
+}
+static method main() → void {
+  pub::baz(new self::Foo::•());
+}
+
+library;
+import self as pub;
+import "dart:core" as core;
+
+class Bar extends core::Object {
+  synthetic constructor •() → pub::Bar*
+    : super core::Object::•()
+    ;
+  method f() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method baz(pub::Bar* bar) → void {
+  core::print("${bar.{pub::Bar::f}{() →* void}.{core::Object::runtimeType}{core::Type*}}");
+}
diff --git a/pkg/front_end/testcases/general/pure_index_expressions.dart.weak.modular.expect b/pkg/front_end/testcases/general/pure_index_expressions.dart.weak.modular.expect
new file mode 100644
index 0000000..e1a3cd8
--- /dev/null
+++ b/pkg/front_end/testcases/general/pure_index_expressions.dart.weak.modular.expect
@@ -0,0 +1,199 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  operator [](self::Class* cls) → self::Class*
+    return new self::Class::•();
+  operator []=(self::Class* cls, self::Class* value) → void {}
+  operator +(self::Class* cls) → self::Class*
+    return cls;
+  method indexGetSetForEffect(core::Map<self::Class*, self::Class*>* map) → void {
+    final self::Class* self = this;
+    let final core::Map<self::Class*, self::Class*>* #t1 = map in #t1.{core::Map::[]}(this){(core::Object*) →* self::Class*} == null ?{self::Class*} #t1.{core::Map::[]=}(this, this){(self::Class*, self::Class*) →* void} : null;
+    let final core::Map<self::Class*, self::Class*>* #t2 = map in #t2.{core::Map::[]}(self){(core::Object*) →* self::Class*} == null ?{self::Class*} #t2.{core::Map::[]=}(self, self){(self::Class*, self::Class*) →* void} : null;
+    map.{core::Map::[]=}(this, this){(self::Class*, self::Class*) →* void};
+    map.{core::Map::[]=}(self, self){(self::Class*, self::Class*) →* void};
+    map.{core::Map::[]}(this){(core::Object*) →* self::Class*};
+    map.{core::Map::[]}(self){(core::Object*) →* self::Class*};
+    let final core::Map<self::Class*, self::Class*>* #t3 = map in #t3.{core::Map::[]=}(this, #t3.{core::Map::[]}(this){(core::Object*) →* self::Class*}.{self::Class::+}(this){(self::Class*) →* self::Class*}){(self::Class*, self::Class*) →* void};
+    let final core::Map<self::Class*, self::Class*>* #t4 = map in #t4.{core::Map::[]=}(self, #t4.{core::Map::[]}(self){(core::Object*) →* self::Class*}.{self::Class::+}(self){(self::Class*) →* self::Class*}){(self::Class*, self::Class*) →* void};
+  }
+  method indexGetSetForValue(core::Map<self::Class*, self::Class*>* map) → void {
+    final self::Class* self = this;
+    dynamic v;
+    v = let final core::Map<self::Class*, self::Class*>* #t5 = map in let final self::Class* #t6 = #t5.{core::Map::[]}(this){(core::Object*) →* self::Class*} in #t6 == null ?{self::Class*} let final void #t7 = #t5.{core::Map::[]=}(this, this){(self::Class*, self::Class*) →* void} in this : #t6;
+    v = let final core::Map<self::Class*, self::Class*>* #t8 = map in let final self::Class* #t9 = #t8.{core::Map::[]}(self){(core::Object*) →* self::Class*} in #t9 == null ?{self::Class*} let final void #t10 = #t8.{core::Map::[]=}(self, self){(self::Class*, self::Class*) →* void} in self : #t9;
+    v = let final core::Map<self::Class*, self::Class*>* #t11 = map in let final void #t12 = #t11.{core::Map::[]=}(this, this){(self::Class*, self::Class*) →* void} in this;
+    v = let final core::Map<self::Class*, self::Class*>* #t13 = map in let final void #t14 = #t13.{core::Map::[]=}(self, self){(self::Class*, self::Class*) →* void} in self;
+    v = map.{core::Map::[]}(this){(core::Object*) →* self::Class*};
+    v = map.{core::Map::[]}(self){(core::Object*) →* self::Class*};
+    v = let final core::Map<self::Class*, self::Class*>* #t15 = map in let final self::Class* #t16 = #t15.{core::Map::[]}(this){(core::Object*) →* self::Class*}.{self::Class::+}(this){(self::Class*) →* self::Class*} in let final void #t17 = #t15.{core::Map::[]=}(this, #t16){(self::Class*, self::Class*) →* void} in #t16;
+    v = let final core::Map<self::Class*, self::Class*>* #t18 = map in let final self::Class* #t19 = #t18.{core::Map::[]}(self){(core::Object*) →* self::Class*}.{self::Class::+}(self){(self::Class*) →* self::Class*} in let final void #t20 = #t18.{core::Map::[]=}(self, #t19){(self::Class*, self::Class*) →* void} in #t19;
+  }
+  method implicitExtensionGetSetForEffect(core::int* i) → void {
+    final self::Class* self = this;
+    let final core::int* #t21 = i in self::Extension|[](#t21, this) == null ?{self::Class*} self::Extension|[]=(#t21, this, this) : null;
+    let final core::int* #t22 = i in self::Extension|[](#t22, self) == null ?{self::Class*} self::Extension|[]=(#t22, self, self) : null;
+    self::Extension|[]=(i, this, this);
+    self::Extension|[]=(i, self, self);
+    self::Extension|[](i, this);
+    self::Extension|[](i, self);
+    let final core::int* #t23 = i in self::Extension|[]=(#t23, this, self::Extension|[](#t23, this).{self::Class::+}(this){(self::Class*) →* self::Class*});
+    let final core::int* #t24 = i in self::Extension|[]=(#t24, self, self::Extension|[](#t24, self).{self::Class::+}(self){(self::Class*) →* self::Class*});
+  }
+  method implicitExtensionGetSetForValue(core::int* i) → void {
+    final self::Class* self = this;
+    dynamic v;
+    v = let final core::int* #t25 = i in let final self::Class* #t26 = self::Extension|[](#t25, this) in #t26 == null ?{self::Class*} let final void #t27 = self::Extension|[]=(#t25, this, this) in this : #t26;
+    v = let final core::int* #t28 = i in let final self::Class* #t29 = self::Extension|[](#t28, self) in #t29 == null ?{self::Class*} let final void #t30 = self::Extension|[]=(#t28, self, self) in self : #t29;
+    v = let final core::int* #t31 = i in let final void #t32 = self::Extension|[]=(#t31, this, this) in this;
+    v = let final core::int* #t33 = i in let final void #t34 = self::Extension|[]=(#t33, self, self) in self;
+    v = self::Extension|[](i, this);
+    v = self::Extension|[](i, self);
+    v = let final core::int* #t35 = i in let final self::Class* #t36 = self::Extension|[](#t35, this).{self::Class::+}(this){(self::Class*) →* self::Class*} in let final void #t37 = self::Extension|[]=(#t35, this, #t36) in #t36;
+    v = let final core::int* #t38 = i in let final self::Class* #t39 = self::Extension|[](#t38, self).{self::Class::+}(self){(self::Class*) →* self::Class*} in let final void #t40 = self::Extension|[]=(#t38, self, #t39) in #t39;
+  }
+  method explicitExtensionGetSetForEffect(core::int* i) → void {
+    final self::Class* self = this;
+    let final core::int* #t41 = i in self::Extension|[](#t41, this) == null ?{self::Class*} self::Extension|[]=(#t41, this, this) : null;
+    let final core::int* #t42 = i in self::Extension|[](#t42, self) == null ?{self::Class*} self::Extension|[]=(#t42, self, self) : null;
+    self::Extension|[]=(i, this, this);
+    self::Extension|[]=(i, self, self);
+    self::Extension|[](i, this);
+    self::Extension|[](i, self);
+    let final core::int* #t43 = i in self::Extension|[]=(#t43, this, self::Extension|[](#t43, this).{self::Class::+}(this){(self::Class*) →* self::Class*});
+    let final core::int* #t44 = i in self::Extension|[]=(#t44, self, self::Extension|[](#t44, self).{self::Class::+}(self){(self::Class*) →* self::Class*});
+  }
+  method explicitExtensionGetSetForValue(core::int* i) → void {
+    final self::Class* self = this;
+    dynamic v;
+    v = let final core::int* #t45 = i in let final self::Class* #t46 = self::Extension|[](#t45, this) in #t46 == null ?{self::Class*} let final void #t47 = self::Extension|[]=(#t45, this, this) in this : #t46;
+    v = let final core::int* #t48 = i in let final self::Class* #t49 = self::Extension|[](#t48, self) in #t49 == null ?{self::Class*} let final void #t50 = self::Extension|[]=(#t48, self, self) in self : #t49;
+    v = let final core::int* #t51 = i in let final void #t52 = self::Extension|[]=(#t51, this, this) in this;
+    v = let final core::int* #t53 = i in let final void #t54 = self::Extension|[]=(#t53, self, self) in self;
+    v = self::Extension|[](i, this);
+    v = self::Extension|[](i, self);
+    v = let final core::int* #t55 = i in let final self::Class* #t56 = self::Extension|[](#t55, this).{self::Class::+}(this){(self::Class*) →* self::Class*} in let final void #t57 = self::Extension|[]=(#t55, this, #t56) in #t56;
+    v = let final core::int* #t58 = i in let final self::Class* #t59 = self::Extension|[](#t58, self).{self::Class::+}(self){(self::Class*) →* self::Class*} in let final void #t60 = self::Extension|[]=(#t58, self, #t59) in #t59;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Subclass extends self::Class {
+  synthetic constructor •() → self::Subclass*
+    : super self::Class::•()
+    ;
+  method superIndexGetSetForEffect() → void {
+    final self::Class* self = this;
+    super.{self::Class::[]}(this) == null ?{self::Class*} super.{self::Class::[]=}(this, this) : null;
+    super.{self::Class::[]}(self) == null ?{self::Class*} super.{self::Class::[]=}(self, self) : null;
+    super.{self::Class::[]=}(this, this);
+    super.{self::Class::[]=}(self, self);
+    super.{self::Class::[]}(this);
+    super.{self::Class::[]}(self);
+    super.{self::Class::[]=}(this, super.{self::Class::[]}(this).{self::Class::+}(this){(self::Class*) →* self::Class*});
+    super.{self::Class::[]=}(self, super.{self::Class::[]}(self).{self::Class::+}(self){(self::Class*) →* self::Class*});
+  }
+  method superIndexGetSetForValue() → void {
+    final self::Class* self = this;
+    dynamic v;
+    v = let final self::Class* #t61 = super.{self::Class::[]}(this) in #t61 == null ?{self::Class*} let final void #t62 = super.{self::Class::[]=}(this, this) in this : #t61;
+    v = let final self::Class* #t63 = super.{self::Class::[]}(self) in #t63 == null ?{self::Class*} let final void #t64 = super.{self::Class::[]=}(self, self) in self : #t63;
+    v = let final void #t65 = super.{self::Class::[]=}(this, this) in this;
+    v = let final void #t66 = super.{self::Class::[]=}(self, self) in self;
+    v = super.{self::Class::[]}(this);
+    v = super.{self::Class::[]}(self);
+    v = let final self::Class* #t67 = super.{self::Class::[]}(this).{self::Class::+}(this){(self::Class*) →* self::Class*} in let final void #t68 = super.{self::Class::[]=}(this, #t67) in #t67;
+    v = let final self::Class* #t69 = super.{self::Class::[]}(self).{self::Class::+}(self){(self::Class*) →* self::Class*} in let final void #t70 = super.{self::Class::[]=}(self, #t69) in #t69;
+  }
+}
+class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2*
+    : super core::Object::•()
+    ;
+  operator +(self::Class2* cls) → self::Class2*
+    return cls;
+  method implicitExtensionGetSetForEffect() → void {
+    final self::Class2* self = this;
+    self::Extension2|[](this, this) == null ?{self::Class2*} self::Extension2|[]=(this, this, this) : null;
+    self::Extension2|[](self, self) == null ?{self::Class2*} self::Extension2|[]=(self, self, self) : null;
+    self::Extension2|[]=(this, this, this);
+    self::Extension2|[]=(self, self, self);
+    self::Extension2|[](this, this);
+    self::Extension2|[](self, self);
+    self::Extension2|[]=(this, this, self::Extension2|[](this, this).{self::Class2::+}(this){(self::Class2*) →* self::Class2*});
+    self::Extension2|[]=(self, self, self::Extension2|[](self, self).{self::Class2::+}(self){(self::Class2*) →* self::Class2*});
+  }
+  method implicitExtensionGetSetForValue() → void {
+    final self::Class2* self = this;
+    dynamic v;
+    v = let final self::Class2* #t71 = self::Extension2|[](this, this) in #t71 == null ?{self::Class2*} let final void #t72 = self::Extension2|[]=(this, this, this) in this : #t71;
+    v = let final self::Class2* #t73 = self::Extension2|[](self, self) in #t73 == null ?{self::Class2*} let final void #t74 = self::Extension2|[]=(self, self, self) in self : #t73;
+    v = let final void #t75 = self::Extension2|[]=(this, this, this) in this;
+    v = let final void #t76 = self::Extension2|[]=(self, self, self) in self;
+    v = self::Extension2|[](this, this);
+    v = self::Extension2|[](self, self);
+    v = let final self::Class2* #t77 = self::Extension2|[](this, this).{self::Class2::+}(this){(self::Class2*) →* self::Class2*} in let final void #t78 = self::Extension2|[]=(this, this, #t77) in #t77;
+    v = let final self::Class2* #t79 = self::Extension2|[](self, self).{self::Class2::+}(self){(self::Class2*) →* self::Class2*} in let final void #t80 = self::Extension2|[]=(self, self, #t79) in #t79;
+  }
+  method explicitExtensionGetSetForEffect() → void {
+    final self::Class2* self = this;
+    self::Extension2|[](this, this) == null ?{self::Class2*} self::Extension2|[]=(this, this, this) : null;
+    self::Extension2|[](self, self) == null ?{self::Class2*} self::Extension2|[]=(self, self, self) : null;
+    self::Extension2|[]=(this, this, this);
+    self::Extension2|[]=(self, self, self);
+    self::Extension2|[](this, this);
+    self::Extension2|[](self, self);
+    self::Extension2|[]=(this, this, self::Extension2|[](this, this).{self::Class2::+}(this){(self::Class2*) →* self::Class2*});
+    self::Extension2|[]=(self, self, self::Extension2|[](self, self).{self::Class2::+}(self){(self::Class2*) →* self::Class2*});
+  }
+  method explicitExtensionGetSetForValue() → void {
+    final self::Class2* self = this;
+    dynamic v;
+    v = let final self::Class2* #t81 = self::Extension2|[](this, this) in #t81 == null ?{self::Class2*} let final void #t82 = self::Extension2|[]=(this, this, this) in this : #t81;
+    v = let final self::Class2* #t83 = self::Extension2|[](self, self) in #t83 == null ?{self::Class2*} let final void #t84 = self::Extension2|[]=(self, self, self) in self : #t83;
+    v = let final void #t85 = self::Extension2|[]=(this, this, this) in this;
+    v = let final void #t86 = self::Extension2|[]=(self, self, self) in self;
+    v = self::Extension2|[](this, this);
+    v = self::Extension2|[](self, self);
+    v = let final self::Class2* #t87 = self::Extension2|[](this, this).{self::Class2::+}(this){(self::Class2*) →* self::Class2*} in let final void #t88 = self::Extension2|[]=(this, this, #t87) in #t87;
+    v = let final self::Class2* #t89 = self::Extension2|[](self, self).{self::Class2::+}(self){(self::Class2*) →* self::Class2*} in let final void #t90 = self::Extension2|[]=(self, self, #t89) in #t89;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on core::int* {
+  operator [] = self::Extension|[];
+  operator []= = self::Extension|[]=;
+}
+extension Extension2 on self::Class2* {
+  operator [] = self::Extension2|[];
+  operator []= = self::Extension2|[]=;
+}
+static method Extension|[](lowered final core::int* #this, self::Class* cls) → self::Class*
+  return new self::Class::•();
+static method Extension|[]=(lowered final core::int* #this, self::Class* cls, self::Class* value) → void {}
+static method Extension2|[](lowered final self::Class2* #this, self::Class2* cls) → self::Class2*
+  return new self::Class2::•();
+static method Extension2|[]=(lowered final self::Class2* #this, self::Class2* cls, self::Class2* value) → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/qualified.dart.weak.modular.expect b/pkg/front_end/testcases/general/qualified.dart.weak.modular.expect
new file mode 100644
index 0000000..59d3ddb
--- /dev/null
+++ b/pkg/front_end/testcases/general/qualified.dart.weak.modular.expect
@@ -0,0 +1,167 @@
+library test.qualified.main;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/qualified.dart:13:11: Error: The name of a constructor must match the name of the enclosing class.
+//   factory WrongName() {}
+//           ^^^^^^^^^
+// pkg/front_end/testcases/general/qualified.dart:11:7: Context: The name of the enclosing class is 'Bad'.
+// class Bad extends lib.Missing {
+//       ^^^
+//
+// pkg/front_end/testcases/general/qualified.dart:11:19: Error: Type 'lib.Missing' not found.
+// class Bad extends lib.Missing {
+//                   ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/qualified.dart:12:3: Error: Type 'lib.Missing' not found.
+//   lib.Missing method() {}
+//   ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/qualified.dart:18:7: Error: The type 'lib.VoidFunction' which is an alias of 'void Function()' can't be used as supertype.
+// class IllegalSupertype extends lib.VoidFunction {}
+//       ^
+// pkg/front_end/testcases/general/qualified_lib.dart:27:9: Context: The issue arises via this type alias.
+// typedef VoidFunction = void Function();
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+import "qualified_lib.dart" as lib;
+
+import "org-dartlang-testcase:///qualified_lib.dart" as lib;
+
+part qualified_part.dart;
+class Bad extends core::Object {
+  method method() → invalid-type {}
+  static factory WrongName() → self::Bad* {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _WithMixin&Supertype&Mixin = lib::Supertype with lib::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_WithMixin&Supertype&Mixin*
+    : super lib::Supertype::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{lib::Mixin::foo}();
+}
+class WithMixin extends self::_WithMixin&Supertype&Mixin {
+  synthetic constructor •() → self::WithMixin*
+    : super self::_WithMixin&Supertype&Mixin::•()
+    ;
+}
+class IllegalSupertype extends core::Object {
+  synthetic constructor •() → self::IllegalSupertype*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<T extends core::Object* = dynamic> extends core::Object { // from org-dartlang-testcase:///qualified_part.dart
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  constructor a() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  static factory b<T extends core::Object* = dynamic>() → self::C<self::C::b::T*>*
+    return lib::C::b<self::C::b::T*>();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::C::•<core::String*>();
+  new self::C::a<core::String*>();
+  new lib::C::a<core::String*>();
+  new lib::C::•<core::String*>();
+  new lib::C::a<core::String*>();
+  new lib::C::a<core::String*>();
+  new self::WithMixin::•().{lib::Supertype::supertypeMethod}(){() →* dynamic};
+  new self::WithMixin::•().{self::_WithMixin&Supertype&Mixin::foo}(){() →* dynamic};
+  new self::IllegalSupertype::•();
+}
+
+library test.qualified.lib;
+import self as lib;
+import "dart:core" as core;
+import "qualified.dart" as self;
+
+import "org-dartlang-testcase:///qualified.dart" as main;
+
+typedef VoidFunction = () →* void;
+class C<T extends core::Object* = dynamic> extends self::C<lib::C::T*> {
+  static final field dynamic _redirecting# = <dynamic>[#C2];
+  constructor •() → lib::C<lib::C::T*>*
+    : super self::C::•()
+    ;
+  constructor a() → lib::C<lib::C::T*>*
+    : super self::C::•()
+    ;
+  static factory b<T extends core::Object* = dynamic>() → lib::C<lib::C::b::T*>*
+    return new lib::C::a<lib::C::b::T*>();
+}
+class Supertype extends core::Object {
+  synthetic constructor •() → lib::Supertype*
+    : super core::Object::•()
+    ;
+  method supertypeMethod() → dynamic {
+    core::print("I'm supertypeMethod form lib.Supertype");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Mixin extends core::Object {
+  synthetic constructor •() → lib::Mixin*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic {
+    core::print("I'm Mixin.foo");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+constants  {
+  #C1 = constructor-tearoff self::C::b
+  #C2 = constructor-tearoff lib::C::b
+}
diff --git a/pkg/front_end/testcases/general/redirecting_constructor.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirecting_constructor.dart.weak.modular.expect
new file mode 100644
index 0000000..293f8a2
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirecting_constructor.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  static factory fisk() → self::A*
+    return new self::B::•();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+static method main() → dynamic {
+  new self::B::•();
+}
+
+constants  {
+  #C1 = constructor-tearoff self::A::fisk
+}
diff --git a/pkg/front_end/testcases/general/redirecting_factory.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirecting_factory.dart.weak.modular.expect
new file mode 100644
index 0000000..ba2466c
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirecting_factory.dart.weak.modular.expect
@@ -0,0 +1,183 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/redirecting_factory.dart:7:28: Error: The constructor function type 'Foo<Tf> Function(int)' isn't a subtype of 'FooBase<Tf> Function(int)'.
+//  - 'Foo' is from 'pkg/front_end/testcases/general/redirecting_factory.dart'.
+//  - 'FooBase' is from 'pkg/front_end/testcases/general/redirecting_factory.dart'.
+//   factory FooBase(int x) = Foo<Tf>;
+//                            ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class FooBase<Tf extends core::Object* = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  abstract get x() → core::int*;
+  static factory •<Tf extends core::Object* = dynamic>(core::int* x) → self::FooBase<self::FooBase::•::Tf*>*
+    return invalid-expression "pkg/front_end/testcases/general/redirecting_factory.dart:7:28: Error: The constructor function type 'Foo<Tf> Function(int)' isn't a subtype of 'FooBase<Tf> Function(int)'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/redirecting_factory.dart'.
+ - 'FooBase' is from 'pkg/front_end/testcases/general/redirecting_factory.dart'.
+  factory FooBase(int x) = Foo<Tf>;
+                           ^";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Foo<T extends core::Object* = dynamic> extends core::Object implements self::FooBase<dynamic> {
+  static final field dynamic _redirecting# = <dynamic>[#C2];
+  static factory •<T extends core::Object* = dynamic>(core::int* x) → self::Foo<self::Foo::•::T*>*
+    return new self::Bar::•<core::String*, self::Foo::•::T*>(x);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar<Sb extends core::Object* = dynamic, Tb extends core::Object* = dynamic> extends core::Object implements self::Foo<self::Bar::Tb*> {
+  field core::int* x;
+  constructor •(core::int* x) → self::Bar<self::Bar::Sb*, self::Bar::Tb*>*
+    : self::Bar::x = x, super core::Object::•() {
+    core::print("Bar<${self::Bar::Sb*},${self::Bar::Tb*}>");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Builder<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Builder<self::Builder::X*>*
+    : super core::Object::•()
+    ;
+  method method() → dynamic {
+    return invalid-expression "pkg/front_end/testcases/general/redirecting_factory.dart:7:28: Error: The constructor function type 'Foo<Tf> Function(int)' isn't a subtype of 'FooBase<Tf> Function(int)'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/redirecting_factory.dart'.
+ - 'FooBase' is from 'pkg/front_end/testcases/general/redirecting_factory.dart'.
+  factory FooBase(int x) = Foo<Tf>;
+                           ^";
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class SimpleCase<A extends core::Object* = dynamic, B extends core::Object* = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C3];
+  static factory •<A extends core::Object* = dynamic, B extends core::Object* = dynamic>() → self::SimpleCase<self::SimpleCase::•::A*, self::SimpleCase::•::B*>*
+    return self::SimpleCaseImpl::•<self::SimpleCase::•::A*, self::SimpleCase::•::B*>();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class SimpleCaseImpl<Ai extends core::Object* = dynamic, Bi extends core::Object* = dynamic> extends core::Object implements self::SimpleCase<self::SimpleCaseImpl::Ai*, self::SimpleCaseImpl::Bi*> {
+  static final field dynamic _redirecting# = <dynamic>[#C4];
+  static factory •<Ai extends core::Object* = dynamic, Bi extends core::Object* = dynamic>() → self::SimpleCaseImpl<self::SimpleCaseImpl::•::Ai*, self::SimpleCaseImpl::•::Bi*>*
+    return new self::SimpleCaseImpl2::•<self::SimpleCaseImpl::•::Ai*, self::SimpleCaseImpl::•::Bi*>();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class SimpleCaseImpl2<Ai2 extends core::Object* = dynamic, Bi2 extends core::Object* = dynamic> extends core::Object implements self::SimpleCaseImpl<self::SimpleCaseImpl2::Ai2*, self::SimpleCaseImpl2::Bi2*> {
+  synthetic constructor •() → self::SimpleCaseImpl2<self::SimpleCaseImpl2::Ai2*, self::SimpleCaseImpl2::Bi2*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Base<M extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Base<self::Base::M*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Mixin<M extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Mixin<self::Mixin::M*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Mix<M extends core::Object* = dynamic> = self::Base<self::Mix::M*> with self::Mixin<self::Mix::M*> {
+  synthetic constructor •() → self::Mix<self::Mix::M*>*
+    : super self::Base::•()
+    ;
+}
+static method main() → dynamic {
+  core::print(invalid-expression "pkg/front_end/testcases/general/redirecting_factory.dart:7:28: Error: The constructor function type 'Foo<Tf> Function(int)' isn't a subtype of 'FooBase<Tf> Function(int)'.
+ - 'Foo' is from 'pkg/front_end/testcases/general/redirecting_factory.dart'.
+ - 'FooBase' is from 'pkg/front_end/testcases/general/redirecting_factory.dart'.
+  factory FooBase(int x) = Foo<Tf>;
+                           ^".{self::FooBase::x}{core::int*});
+  new self::SimpleCaseImpl2::•<core::int*, core::double*>();
+  new self::Mix::•<core::double*>();
+}
+
+constants  {
+  #C1 = constructor-tearoff self::FooBase::•
+  #C2 = constructor-tearoff self::Foo::•
+  #C3 = constructor-tearoff self::SimpleCase::•
+  #C4 = constructor-tearoff self::SimpleCaseImpl::•
+}
diff --git a/pkg/front_end/testcases/general/redirecting_factory_chain_test.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirecting_factory_chain_test.dart.weak.modular.expect
new file mode 100644
index 0000000..e86259e
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirecting_factory_chain_test.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library redirecting_factory_constructors.chain_test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1, #C2];
+  constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  static factory first() → self::A*
+    return new self::A::•();
+  static factory second() → self::A*
+    return self::A::first();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::A::•();
+}
+
+constants  {
+  #C1 = constructor-tearoff self::A::first
+  #C2 = constructor-tearoff self::A::second
+}
diff --git a/pkg/front_end/testcases/general/redirecting_factory_const_inference.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirecting_factory_const_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..3dc0b99
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirecting_factory_const_inference.dart.weak.modular.expect
@@ -0,0 +1,72 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class _X<T extends core::Object* = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  static factory •<T extends core::Object* = dynamic>() → self::_X<self::_X::•::T*>*
+    return new self::_Y::•<self::_X::•::T*>();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class _Y<T extends core::Object* = dynamic> extends core::Object implements self::_X<self::_Y::T*> /*hasConstConstructor*/  {
+  const constructor •() → self::_Y<self::_Y::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::_X<self::A::T*>* x;
+  constructor •(self::_X<self::A::T*>* x) → self::A<self::A::T*>*
+    : self::A::x = x, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::Object* = dynamic> extends self::A<self::B::T*> {
+  constructor •() → self::B<self::B::T*>*
+    : super self::A::•(#C2)
+    ;
+}
+static method main() → dynamic {
+  dynamic x = new self::B::•<dynamic>().{self::A::x}{self::_X<dynamic>*};
+  if(!(x is self::_Y<Null>*)) {
+    throw "Unexpected run-time type: `new B().x` is ${x.{core::Object::runtimeType}{core::Type*}}, but `_Y<Null>` expected";
+  }
+}
+
+constants  {
+  #C1 = constructor-tearoff self::_X::•
+  #C2 = self::_Y<Null> {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///redirecting_factory_const_inference.dart:
+- _Y. (from org-dartlang-testcase:///redirecting_factory_const_inference.dart:14:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/redirecting_factory_default_value.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirecting_factory_default_value.dart.weak.modular.expect
new file mode 100644
index 0000000..4a74b87
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirecting_factory_default_value.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/redirecting_factory_default_value.dart:10:35: Error: Can't have a default value here because any default values of 'A' would be used instead.
+// Try removing the default value.
+//   factory A.redirect([int field = 87]) = A;
+//                                   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  final field core::int field;
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor •([core::int field = #C2]) → self::A
+    : self::A::field = field, super core::Object::•()
+    ;
+  static factory redirect([core::int field]) → self::A
+    return new self::A::•(field);
+}
+static method main() → dynamic {
+  self::expect(42, new self::A::•().{self::A::field}{core::int});
+  self::expect(123, new self::A::•(123).{self::A::field}{core::int});
+  self::expect(42, new self::A::•().{self::A::field}{core::int});
+  self::expect(123, new self::A::•(123).{self::A::field}{core::int});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = constructor-tearoff self::A::redirect
+  #C2 = 42
+}
diff --git a/pkg/front_end/testcases/general/redirecting_factory_default_value.dart.weak.outline.expect b/pkg/front_end/testcases/general/redirecting_factory_default_value.dart.weak.outline.expect
index 7669a3f..05e4ae1 100644
--- a/pkg/front_end/testcases/general/redirecting_factory_default_value.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/general/redirecting_factory_default_value.dart.weak.outline.expect
@@ -5,7 +5,7 @@
 class A extends core::Object {
   final field core::int field;
   static final field dynamic _redirecting# = <dynamic>[self::A::redirect]/*isLegacy*/;
-  constructor •([core::int field]) → self::A
+  constructor •([core::int field = 42]) → self::A
     ;
   static factory redirect([core::int field]) → self::A
     return new self::A::•(field);
diff --git a/pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart.weak.modular.expect
new file mode 100644
index 0000000..f674d71
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart.weak.modular.expect
@@ -0,0 +1,196 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:47:10: Error: Superclass has no method named '[]'.
+//     super[new Class1()];
+//          ^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:49:10: Error: Superclass has no method named '[]='.
+//     super[0] = new Class1();
+//          ^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:51:11: Error: Superclass has no setter named 'foo'.
+//     super.foo = new Class1();
+//           ^^^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:53:11: Error: Superclass has no method named 'foo'.
+//     super.foo(new Class1());
+//           ^^^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:55:11: Error: Superclass has no method named '+'.
+//     super + new Class1();
+//           ^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:20:5: Error: The operator 'unary-' isn't defined for the class 'Class1'.
+//  - 'Class1' is from 'pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart'.
+// Try correcting the operator to an existing operator, or defining a 'unary-' operator.
+//     -new Class1();
+//     ^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:22:15: Error: The operator '-' isn't defined for the class 'String'.
+// Try correcting the operator to an existing operator, or defining a '-' operator.
+//     ('' + '') - new Class1();
+//               ^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:24:12: Error: The operator '[]=' isn't defined for the class 'int'.
+// Try correcting the operator to an existing operator, or defining a '[]=' operator.
+//     (0 + 1)[0] = new Class1();
+//            ^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:25:8: Error: The operator '[]=' isn't defined for the class 'Class2'.
+//  - 'Class2' is from 'pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart'.
+// Try correcting the operator to an existing operator, or defining a '[]=' operator.
+//     _c2[0] = new Class1();
+//        ^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:27:12: Error: The operator '[]' isn't defined for the class 'int'.
+// Try correcting the operator to an existing operator, or defining a '[]' operator.
+//     (0 + 1)[new Class1()];
+//            ^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:29:18: Error: The getter 'foo' isn't defined for the class 'Class1'.
+//  - 'Class1' is from 'pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'foo'.
+//     new Class1().foo;
+//                  ^^^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:31:13: Error: The setter 'foo' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'foo'.
+//     (0 + 1).foo = new Class1();
+//             ^^^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:33:18: Error: The method 'foo' isn't defined for the class 'Class1'.
+//  - 'Class1' is from 'pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+//     new Class1().foo();
+//                  ^^^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:35:17: Error: The method 'call' isn't defined for the class 'Class1'.
+//  - 'Class1' is from 'pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'call'.
+//     new Class1()();
+//                 ^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:37:23: Error: 'field' isn't a function or method and can't be invoked.
+//     new Class1().field();
+//                       ^^^^...
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:39:24: Error: 'getter' isn't a function or method and can't be invoked.
+//     new Class1().getter();
+//                        ^^^^...
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:41:8: Error: 'call' isn't a function or method and can't be invoked.
+//     _c2(new Class1());
+//        ^^^^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:43:18: Error: Duplicated named argument 'a'.
+//     method(a: 0, a: new Class1());
+//                  ^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:45:18: Error: Duplicated named argument 'a'.
+//     method(a: 0, a: 1, a: new Class1());
+//                  ^
+//
+// pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:45:24: Error: Duplicated named argument 'a'.
+//     method(a: 0, a: 1, a: new Class1());
+//                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  field core::int field = 0;
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor _() → self::Class1
+    : super core::Object::•()
+    ;
+  static factory •() → self::Class1
+    return new self::Class1::_();
+  get getter() → core::int
+    return 0;
+}
+class Class2 extends self::Class1 {
+  final field self::Class2 _c2;
+  constructor •(self::Class2 _c2) → self::Class2
+    : self::Class2::_c2 = _c2, super self::Class1::_() {
+    invalid-expression "pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:20:5: Error: The operator 'unary-' isn't defined for the class 'Class1'.
+ - 'Class1' is from 'pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart'.
+Try correcting the operator to an existing operator, or defining a 'unary-' operator.
+    -new Class1();
+    ^" in new self::Class1::_(){<unresolved>}.unary-();
+    invalid-expression "pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:22:15: Error: The operator '-' isn't defined for the class 'String'.
+Try correcting the operator to an existing operator, or defining a '-' operator.
+    ('' + '') - new Class1();
+              ^" in "".{core::String::+}(""){(core::String) → core::String}{<unresolved>}.-(new self::Class1::_());
+    invalid-expression "pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:24:12: Error: The operator '[]=' isn't defined for the class 'int'.
+Try correcting the operator to an existing operator, or defining a '[]=' operator.
+    (0 + 1)[0] = new Class1();
+           ^" in 0.{core::num::+}(1){(core::num) → core::int}{<unresolved>}.[]=(0, new self::Class1::_());
+    invalid-expression "pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:25:8: Error: The operator '[]=' isn't defined for the class 'Class2'.
+ - 'Class2' is from 'pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart'.
+Try correcting the operator to an existing operator, or defining a '[]=' operator.
+    _c2[0] = new Class1();
+       ^" in this.{self::Class2::_c2}{self::Class2}{<unresolved>}.[]=(0, new self::Class1::_());
+    invalid-expression "pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:27:12: Error: The operator '[]' isn't defined for the class 'int'.
+Try correcting the operator to an existing operator, or defining a '[]' operator.
+    (0 + 1)[new Class1()];
+           ^" in 0.{core::num::+}(1){(core::num) → core::int}{<unresolved>}.[](new self::Class1::_());
+    invalid-expression "pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:29:18: Error: The getter 'foo' isn't defined for the class 'Class1'.
+ - 'Class1' is from 'pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'foo'.
+    new Class1().foo;
+                 ^^^" in new self::Class1::_(){<unresolved>}.foo;
+    invalid-expression "pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:31:13: Error: The setter 'foo' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'foo'.
+    (0 + 1).foo = new Class1();
+            ^^^" in 0.{core::num::+}(1){(core::num) → core::int}{<unresolved>}.foo = new self::Class1::_();
+    invalid-expression "pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:33:18: Error: The method 'foo' isn't defined for the class 'Class1'.
+ - 'Class1' is from 'pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+    new Class1().foo();
+                 ^^^" in new self::Class1::_(){<unresolved>}.foo();
+    invalid-expression "pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:35:17: Error: The method 'call' isn't defined for the class 'Class1'.
+ - 'Class1' is from 'pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'call'.
+    new Class1()();
+                ^" in new self::Class1::_(){<unresolved>}.call();
+    invalid-expression "pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:37:23: Error: 'field' isn't a function or method and can't be invoked.
+    new Class1().field();
+                      ^^^^..." in new self::Class1::_().{self::Class1::field}{core::int}{<unresolved>}.call();
+    invalid-expression "pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:39:24: Error: 'getter' isn't a function or method and can't be invoked.
+    new Class1().getter();
+                       ^^^^..." in new self::Class1::_().{self::Class1::getter}{core::int}{<unresolved>}.call();
+    let final self::Class2 #t1 = this.{self::Class2::_c2}{self::Class2} in let final self::Class1 #t2 = new self::Class1::_() in invalid-expression "pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:41:8: Error: 'call' isn't a function or method and can't be invoked.
+    _c2(new Class1());
+       ^^^^" in #t1.{self::Class2::call}{core::int}{<unresolved>}.call(#t2);
+    this.{self::Class2::method}(a: invalid-expression "pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:43:18: Error: Duplicated named argument 'a'.
+    method(a: 0, a: new Class1());
+                 ^" in block {
+      0;
+    } =>new self::Class1::_()){({a: dynamic}) → dynamic};
+    this.{self::Class2::method}(a: invalid-expression "pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:45:24: Error: Duplicated named argument 'a'.
+    method(a: 0, a: 1, a: new Class1());
+                       ^" in block {
+      invalid-expression "pkg/front_end/testcases/general/redirecting_factory_invocation_in_invalid.dart:45:18: Error: Duplicated named argument 'a'.
+    method(a: 0, a: 1, a: new Class1());
+                 ^" in block {
+        0;
+      } =>1;
+    } =>new self::Class1::_()){({a: dynamic}) → dynamic};
+    super.[](new self::Class1::_());
+    super.[]=(0, new self::Class1::_());
+    super.foo = new self::Class1::_();
+    super.foo(new self::Class1::_());
+    super.+(new self::Class1::_());
+  }
+  method method({dynamic a = #C2}) → dynamic {}
+  get call() → core::int
+    return 0;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::Class1::•
+  #C2 = null
+}
diff --git a/pkg/front_end/testcases/general/redirecting_factory_invocation_metadata.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirecting_factory_invocation_metadata.dart.weak.modular.expect
new file mode 100644
index 0000000..4f4319e
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirecting_factory_invocation_metadata.dart.weak.modular.expect
@@ -0,0 +1,106 @@
+@#C1
+library name /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///redirecting_factory_invocation_metadata.dart" as self;
+export "org-dartlang-testcase:///redirecting_factory_invocation_metadata.dart";
+
+@#C1
+part redirecting_factory_invocation_metadata_lib.dart;
+@#C1
+typedef Typedef1<@#C1 unrelated T extends core::Object? = dynamic> = <T extends core::Object? = dynamic>(@#C1 self::Class<dynamic> #t1, [@#C1 self::Class<dynamic> #t2]) → dynamic;
+@#C1
+typedef Typedef2<@#C1 unrelated T extends core::Object? = dynamic> = <T extends core::Object? = dynamic>(@#C1 self::Class<dynamic> #t3, {@#C1 self::Class<dynamic> o2}) → dynamic;
+@#C1
+typedef Typedef3<@#C1 unrelated T extends core::Object? = dynamic> = (@#C1 dynamic o1, [@#C1 dynamic o2]) → void;
+@#C1
+typedef Typedef4<@#C1 unrelated T extends core::Object? = dynamic> = (@#C1 dynamic o1, {@#C1 dynamic o2}) → void;
+@#C1
+class Const extends core::Object /*hasConstConstructor*/  {
+  static final field dynamic _redirecting# = <dynamic>[#C2]/*isLegacy*/;
+  const constructor internal() → self::Const
+    : super core::Object::•()
+    ;
+  static factory •() → self::Const
+    return new self::Const::internal();
+}
+class Class<@#C1 T extends core::Object? = dynamic> extends core::Object {
+  @#C1
+  field <T extends core::Object? = dynamic>(dynamic, {o2: dynamic}) → Null field = <@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, {@#C1 dynamic o2 = #C3}) → Null {
+    @#C1 dynamic l1;
+    @#C1
+    function l2<@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, {@#C1 dynamic o2 = #C3}) → Null {}
+  };
+  @#C1
+  constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  @#C1
+  method method1<@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, [@#C1 dynamic o2 = #C3]) → dynamic {
+    @#C1 dynamic l1;
+    @#C1
+    function l2<@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, [@#C1 dynamic o2 = #C3]) → Null {}
+  }
+  @#C1
+  method method2<@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, {@#C1 dynamic o2 = #C3}) → dynamic {
+    <@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, {@#C1 dynamic o2 = #C3}) → Null {};
+  }
+}
+@#C1
+extension Extension<@#C1 T extends core::Object? = dynamic> on self::Class<T%> {
+  static field field = self::Extension|field;
+  method method1 = self::Extension|method1;
+  tearoff method1 = self::Extension|get#method1;
+  method method2 = self::Extension|method2;
+  tearoff method2 = self::Extension|get#method2;
+}
+@#C1
+static field <T extends core::Object? = dynamic>(dynamic, [dynamic]) → Null field = <@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, [@#C1 dynamic o2 = #C3]) → Null {
+  @#C1 dynamic l1;
+  @#C1
+  function l2<@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, [@#C1 dynamic o2 = #C3]) → Null {}
+};
+@#C1
+static field <T extends core::Object? = dynamic>(dynamic, [dynamic]) → Null Extension|field = <@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, [@#C1 dynamic o2 = #C3]) → Null {
+  @#C1 dynamic l1;
+  @#C1
+  function l2<@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, [@#C1 dynamic o2 = #C3]) → Null {}
+};
+@#C1
+static method method1<@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, [@#C1 dynamic o2 = #C3]) → dynamic {
+  @#C1 dynamic l1;
+  @#C1
+  function l2<@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, [@#C1 dynamic o2 = #C3]) → Null {}
+}
+@#C1
+static method method2<@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, {@#C1 dynamic o2 = #C3}) → dynamic {
+  <@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, {@#C1 dynamic o2 = #C3}) → Null {};
+}
+@#C1
+static method Extension|method1<#T extends core::Object? = dynamic, @#C1 T extends core::Object? = dynamic>(lowered final self::Class<self::Extension|method1::#T%> #this, @#C1 dynamic o1, [@#C1 dynamic o2 = #C3]) → dynamic {
+  @#C1 dynamic l1;
+  @#C1
+  function l2<@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, [@#C1 dynamic o2 = #C3]) → Null {}
+}
+static method Extension|get#method1<#T extends core::Object? = dynamic>(lowered final self::Class<self::Extension|get#method1::#T%> #this) → <T extends core::Object? = dynamic>(dynamic, [dynamic]) → dynamic
+  return <T extends core::Object? = dynamic>(dynamic o1, [dynamic o2 = #C3]) → dynamic => self::Extension|method1<self::Extension|get#method1::#T%, T%>(#this, o1, o2);
+@#C1
+static method Extension|method2<#T extends core::Object? = dynamic, @#C1 T extends core::Object? = dynamic>(lowered final self::Class<self::Extension|method2::#T%> #this, @#C1 dynamic o1, {@#C1 dynamic o2 = #C3}) → dynamic {
+  <@#C1 T extends core::Object? = dynamic>(@#C1 dynamic o1, {@#C1 dynamic o2 = #C3}) → Null {};
+}
+static method Extension|get#method2<#T extends core::Object? = dynamic>(lowered final self::Class<self::Extension|get#method2::#T%> #this) → <T extends core::Object? = dynamic>(dynamic, {o2: dynamic}) → dynamic
+  return <T extends core::Object? = dynamic>(dynamic o1, {dynamic o2 = #C3}) → dynamic => self::Extension|method2<self::Extension|get#method2::#T%, T%>(#this, o1, o2: o2);
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Const {}
+  #C2 = constructor-tearoff self::Const::•
+  #C3 = null
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///redirecting_factory_invocation_metadata.dart:
+- Const.internal (from org-dartlang-testcase:///redirecting_factory_invocation_metadata.dart:19:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/redirecting_factory_metadata.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirecting_factory_metadata.dart.weak.modular.expect
new file mode 100644
index 0000000..9b12539
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirecting_factory_metadata.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  constructor named(dynamic p) → self::Foo*
+    : super core::Object::•()
+    ;
+  @#C2
+  static factory •(@#C3 @#C4 dynamic p) → self::Foo*
+    return new self::Foo::named(p);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field core::int* forParameter = #C3;
+static const field core::int* forFactoryItself = #C2;
+static const field core::int* anotherForParameter = #C4;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::Foo::•
+  #C2 = 2
+  #C3 = 1
+  #C4 = 3
+}
diff --git a/pkg/front_end/testcases/general/redirecting_factory_simple_test.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirecting_factory_simple_test.dart.weak.modular.expect
new file mode 100644
index 0000000..f2a4360
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirecting_factory_simple_test.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library redirecting_factory_constructors.simple_test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  static factory redir() → self::A*
+    return new self::A::•();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::A::•();
+}
+
+constants  {
+  #C1 = constructor-tearoff self::A::redir
+}
diff --git a/pkg/front_end/testcases/general/redirecting_factory_typeargs_test.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirecting_factory_typeargs_test.dart.weak.modular.expect
new file mode 100644
index 0000000..16c46e9
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirecting_factory_typeargs_test.dart.weak.modular.expect
@@ -0,0 +1,54 @@
+library redirecting_factory_constructors.typeargs_test;
+import self as self;
+import "dart:core" as core;
+
+class X extends core::Object {
+  synthetic constructor •() → self::X*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Y extends self::X {
+  synthetic constructor •() → self::Y*
+    : super self::X::•()
+    ;
+}
+class A extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  static factory redir() → self::A*
+    return new self::B::•<self::Y*>();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends self::X*> extends self::A {
+  constructor •() → self::B<self::B::T*>*
+    : super self::A::•()
+    ;
+}
+static method main() → dynamic {
+  new self::B::•<self::Y*>();
+}
+
+constants  {
+  #C1 = constructor-tearoff self::A::redir
+}
diff --git a/pkg/front_end/testcases/general/redirecting_factory_typeparam_test.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirecting_factory_typeparam_test.dart.weak.modular.expect
new file mode 100644
index 0000000..469f2af
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirecting_factory_typeparam_test.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library redirecting_factory_constructors.typeparam_test;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic, S extends core::Object* = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  constructor •(self::A::T* t, self::A::S* s) → self::A<self::A::T*, self::A::S*>*
+    : super core::Object::•()
+    ;
+  static factory redir<T extends core::Object* = dynamic, S extends core::Object* = dynamic>(self::A::redir::T* t, self::A::redir::S* s) → self::A<self::A::redir::T*, self::A::redir::S*>*
+    return new self::A::•<self::A::redir::T*, self::A::redir::S*>(t, s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::A::•<core::int*, core::String*>(42, "foobar");
+}
+
+constants  {
+  #C1 = constructor-tearoff self::A::redir
+}
diff --git a/pkg/front_end/testcases/general/redirecting_factory_typeparambounds_test.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirecting_factory_typeparambounds_test.dart.weak.modular.expect
new file mode 100644
index 0000000..98d4e12
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirecting_factory_typeparambounds_test.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library redirecting_factory_constructors.typeparambounds_test;
+import self as self;
+import "dart:core" as core;
+
+class X extends core::Object {
+  synthetic constructor •() → self::X*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Y extends self::X {
+  synthetic constructor •() → self::Y*
+    : super self::X::•()
+    ;
+}
+class A<T extends core::Object* = dynamic, S extends self::A::T* = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  constructor •(self::A::T* t, self::A::S* s) → self::A<self::A::T*, self::A::S*>*
+    : super core::Object::•()
+    ;
+  static factory redir<T extends core::Object* = dynamic, S extends self::A::redir::T* = dynamic>(self::A::redir::T* t, self::A::redir::S* s) → self::A<self::A::redir::T*, self::A::redir::S*>*
+    return new self::A::•<self::A::redir::T*, self::A::redir::S*>(t, s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::A::•<self::X*, self::Y*>(new self::X::•(), new self::Y::•());
+}
+
+constants  {
+  #C1 = constructor-tearoff self::A::redir
+}
diff --git a/pkg/front_end/testcases/general/redirecting_initializer_arguments_assignable_test.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirecting_initializer_arguments_assignable_test.dart.weak.modular.expect
new file mode 100644
index 0000000..a539f39
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirecting_initializer_arguments_assignable_test.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class X extends core::Object {
+  synthetic constructor •() → self::X*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Foo<T extends self::X*> extends core::Object {
+  covariant-by-class field self::Foo::T* x;
+  constructor fromX(self::X* _init) → self::Foo<self::Foo::T*>*
+    : this self::Foo::_internal(x: _init as{TypeError} self::Foo::T*)
+    ;
+  constructor fromT(self::Foo::T* _init) → self::Foo<self::Foo::T*>*
+    : this self::Foo::_internal(x: _init)
+    ;
+  constructor _internal({self::Foo::T* x = #C1}) → self::Foo<self::Foo::T*>*
+    : self::Foo::x = x, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/redirecting_initializer_arguments_test.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirecting_initializer_arguments_test.dart.weak.modular.expect
new file mode 100644
index 0000000..6c401a6
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirecting_initializer_arguments_test.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/redirecting_initializer_arguments_test.dart:12:46: Error: The argument type 'String' can't be assigned to the parameter type 'T'.
+//   Foo.from(String _init) : this._internal(x: _init);
+//                                              ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::Foo::T* x;
+  constructor from(core::String* _init) → self::Foo<self::Foo::T*>*
+    : this self::Foo::_internal(x: invalid-expression "pkg/front_end/testcases/general/redirecting_initializer_arguments_test.dart:12:46: Error: The argument type 'String' can't be assigned to the parameter type 'T'.
+  Foo.from(String _init) : this._internal(x: _init);
+                                             ^" in _init as{TypeError} Never)
+    ;
+  constructor _internal({self::Foo::T* x = #C1}) → self::Foo<self::Foo::T*>*
+    : self::Foo::x = x, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/general/redirection_chain_type_arguments.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirection_chain_type_arguments.dart.weak.modular.expect
new file mode 100644
index 0000000..273bd861
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirection_chain_type_arguments.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  constructor empty() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  static factory •<T extends core::Object* = dynamic>() → self::A<self::A::•::T*>*
+    return self::B::•<self::A::•::T*, core::num*>();
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<U extends core::Object* = dynamic, W extends core::Object* = dynamic> extends self::A<self::B::U*> {
+  static final field dynamic _redirecting# = <dynamic>[#C2];
+  constructor empty() → self::B<self::B::U*, self::B::W*>*
+    : super self::A::empty()
+    ;
+  static factory •<U extends core::Object* = dynamic, W extends core::Object* = dynamic>() → self::B<self::B::•::U*, self::B::•::W*>*
+    return new self::C::•<self::B::•::U*, self::B::•::W*, core::String*>();
+}
+class C<V extends core::Object* = dynamic, S extends core::Object* = dynamic, R extends core::Object* = dynamic> extends self::B<self::C::V*, self::C::S*> {
+  constructor •() → self::C<self::C::V*, self::C::S*, self::C::R*>*
+    : super self::B::empty()
+    ;
+  method toString() → core::String*
+    return "${self::C::V*},${self::C::S*},${self::C::R*}";
+}
+static method main() → dynamic {
+  exp::Expect::equals("${new self::C::•<core::int*, core::num*, core::String*>()}", "int,num,String");
+}
+
+constants  {
+  #C1 = constructor-tearoff self::A::•
+  #C2 = constructor-tearoff self::B::•
+}
diff --git a/pkg/front_end/testcases/general/redirection_chain_type_arguments_subst.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirection_chain_type_arguments_subst.dart.weak.modular.expect
new file mode 100644
index 0000000..516d00c
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirection_chain_type_arguments_subst.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+abstract class A<T extends core::Object* = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  constructor empty() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  static factory •<T extends core::Object* = dynamic>() → self::A<self::A::•::T*>*
+    return self::B::•<self::A::•::T*, core::List<self::A::•::T*>*>();
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B<U extends core::Object* = dynamic, W extends core::Object* = dynamic> extends self::A<self::B::U*> {
+  static final field dynamic _redirecting# = <dynamic>[#C2];
+  constructor empty() → self::B<self::B::U*, self::B::W*>*
+    : super self::A::empty()
+    ;
+  static factory •<U extends core::Object* = dynamic, W extends core::Object* = dynamic>() → self::B<self::B::•::U*, self::B::•::W*>*
+    return new self::C::•<self::B::•::U*, self::B::•::W*, core::Map<self::B::•::U*, self::B::•::W*>*>();
+}
+class C<V extends core::Object* = dynamic, S extends core::Object* = dynamic, R extends core::Object* = dynamic> extends self::B<self::C::V*, self::C::S*> {
+  constructor •() → self::C<self::C::V*, self::C::S*, self::C::R*>*
+    : super self::B::empty()
+    ;
+  method toString() → core::String*
+    return "${self::C::V*},${self::C::S*},${self::C::R*}";
+}
+static method main() → dynamic {
+  exp::Expect::equals("${new self::C::•<core::int*, core::List<core::int*>*, core::Map<core::int*, core::List<core::int*>*>*>()}", "int,List<int>,Map<int, List<int>>");
+}
+
+constants  {
+  #C1 = constructor-tearoff self::A::•
+  #C2 = constructor-tearoff self::B::•
+}
diff --git a/pkg/front_end/testcases/general/redirection_type_arguments.dart.weak.modular.expect b/pkg/front_end/testcases/general/redirection_type_arguments.dart.weak.modular.expect
new file mode 100644
index 0000000..be27ced
--- /dev/null
+++ b/pkg/front_end/testcases/general/redirection_type_arguments.dart.weak.modular.expect
@@ -0,0 +1,47 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+class A extends core::Object /*hasConstConstructor*/  {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  const constructor empty() → self::A*
+    : super core::Object::•()
+    ;
+  static factory •() → self::A*
+    return new self::B::•<core::String*>();
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::Object* = dynamic> extends self::A /*hasConstConstructor*/  {
+  const constructor •() → self::B<self::B::T*>*
+    : super self::A::empty()
+    ;
+  method toString() → core::String*
+    return "${self::B::T*}";
+}
+static method main() → void {
+  exp::Expect::equals("${#C2}", "String");
+}
+
+constants  {
+  #C1 = constructor-tearoff self::A::•
+  #C2 = self::B<core::String*> {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///redirection_type_arguments.dart:
+- B. (from org-dartlang-testcase:///redirection_type_arguments.dart:16:9)
+- A.empty (from org-dartlang-testcase:///redirection_type_arguments.dart:12:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/regression_flutter51828.dart.weak.modular.expect b/pkg/front_end/testcases/general/regression_flutter51828.dart.weak.modular.expect
new file mode 100644
index 0000000..7cc953e
--- /dev/null
+++ b/pkg/front_end/testcases/general/regression_flutter51828.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method foo(dynamic x) → asy::Future<void>* async {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method bar(dynamic x) → asy::Future<void>* async {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic async 
+  return <asy::Future<void>*>[new self::A::•().{self::A::foo}(await null){(dynamic) →* asy::Future<void>*}, new self::B::•().{self::B::bar}(await null){(dynamic) →* asy::Future<void>*}];
diff --git a/pkg/front_end/testcases/general/reject_generic_function_types_in_bounds.dart.weak.modular.expect b/pkg/front_end/testcases/general/reject_generic_function_types_in_bounds.dart.weak.modular.expect
new file mode 100644
index 0000000..dcd7a33
--- /dev/null
+++ b/pkg/front_end/testcases/general/reject_generic_function_types_in_bounds.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/reject_generic_function_types_in_bounds.dart:8:12: Error: Type variables can't have generic function types in their bounds.
+// class Hest<TypeX extends TypeY Function<TypeY>(TypeY)> {}
+//            ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Hest<TypeX extends <TypeY extends core::Object* = dynamic>(TypeY*) →* TypeY* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Hest<self::Hest::TypeX*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/return_with_unknown_type_in_context.dart.weak.modular.expect b/pkg/front_end/testcases/general/return_with_unknown_type_in_context.dart.weak.modular.expect
new file mode 100644
index 0000000..7704535
--- /dev/null
+++ b/pkg/front_end/testcases/general/return_with_unknown_type_in_context.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method f(core::List<dynamic>* x) → core::bool* {
+  return x.{core::Iterable::expand}<dynamic>((dynamic y) → core::Iterable<dynamic>* {
+    return y{dynamic}.split(",") as{TypeError,ForDynamic} core::Iterable<dynamic>*;
+  }){((dynamic) →* core::Iterable<dynamic>*) →* core::Iterable<dynamic>*}.{core::Iterable::any}((dynamic y) → core::bool* => y =={core::Object::==}{(core::Object*) →* core::bool*} "z"){((dynamic) →* core::bool*) →* core::bool*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/sdk_diagnostic.dart.weak.modular.expect b/pkg/front_end/testcases/general/sdk_diagnostic.dart.weak.modular.expect
new file mode 100644
index 0000000..7131789
--- /dev/null
+++ b/pkg/front_end/testcases/general/sdk_diagnostic.dart.weak.modular.expect
@@ -0,0 +1,82 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/sdk_diagnostic.dart:5:7: Error: The non-abstract class 'C' is missing implementations for these members:
+//  - Iterable.iterator
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class C extends Iterable<Object> {
+//       ^
+// sdk/lib/core/iterable.dart:148:19: Context: 'Iterable.iterator' is defined here.
+//   Iterator<E> get iterator;
+//                   ^^^^^^^^
+//
+// pkg/front_end/testcases/general/sdk_diagnostic.dart:12:8: Error: Too few positional arguments: 1 required, 0 given.
+//   print(incorrectArgument: "fisk");
+//        ^
+// sdk/lib/core/print.dart:8:6: Context: Found this candidate, but the arguments don't match.
+// void print(Object? object) {
+//      ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Iterable<core::Object*> {
+  synthetic constructor •() → self::C*
+    : super core::Iterable::•()
+    ;
+  abstract member-signature method cast<R extends core::Object* = dynamic>() → core::Iterable<self::C::cast::R*>*; -> core::Iterable::cast
+  abstract member-signature method followedBy(covariant-by-class core::Iterable<core::Object*>* other) → core::Iterable<core::Object*>*; -> core::Iterable::followedBy
+  abstract member-signature method map<T extends core::Object* = dynamic>((core::Object*) →* self::C::map::T* toElement) → core::Iterable<self::C::map::T*>*; -> core::Iterable::map
+  abstract member-signature method where((core::Object*) →* core::bool* test) → core::Iterable<core::Object*>*; -> core::Iterable::where
+  abstract member-signature method whereType<T extends core::Object* = dynamic>() → core::Iterable<self::C::whereType::T*>*; -> core::Iterable::whereType
+  abstract member-signature method expand<T extends core::Object* = dynamic>((core::Object*) →* core::Iterable<self::C::expand::T*>* toElements) → core::Iterable<self::C::expand::T*>*; -> core::Iterable::expand
+  abstract member-signature method contains(core::Object* element) → core::bool*; -> core::Iterable::contains
+  abstract member-signature method forEach((core::Object*) →* void action) → void; -> core::Iterable::forEach
+  abstract member-signature method reduce(covariant-by-class (core::Object*, core::Object*) →* core::Object* combine) → core::Object*; -> core::Iterable::reduce
+  abstract member-signature method fold<T extends core::Object* = dynamic>(self::C::fold::T* initialValue, (self::C::fold::T*, core::Object*) →* self::C::fold::T* combine) → self::C::fold::T*; -> core::Iterable::fold
+  abstract member-signature method every((core::Object*) →* core::bool* test) → core::bool*; -> core::Iterable::every
+  abstract member-signature method join([core::String* separator = #C1]) → core::String*; -> core::Iterable::join
+  abstract member-signature method any((core::Object*) →* core::bool* test) → core::bool*; -> core::Iterable::any
+  abstract member-signature method toList({core::bool* growable = #C2}) → core::List<core::Object*>*; -> core::Iterable::toList
+  abstract member-signature method toSet() → core::Set<core::Object*>*; -> core::Iterable::toSet
+  abstract member-signature get length() → core::int*; -> core::Iterable::length
+  abstract member-signature get isEmpty() → core::bool*; -> core::Iterable::isEmpty
+  abstract member-signature get isNotEmpty() → core::bool*; -> core::Iterable::isNotEmpty
+  abstract member-signature method take(core::int* count) → core::Iterable<core::Object*>*; -> core::Iterable::take
+  abstract member-signature method takeWhile((core::Object*) →* core::bool* test) → core::Iterable<core::Object*>*; -> core::Iterable::takeWhile
+  abstract member-signature method skip(core::int* count) → core::Iterable<core::Object*>*; -> core::Iterable::skip
+  abstract member-signature method skipWhile((core::Object*) →* core::bool* test) → core::Iterable<core::Object*>*; -> core::Iterable::skipWhile
+  abstract member-signature method firstWhere((core::Object*) →* core::bool* test, {covariant-by-class () →* core::Object* orElse = #C3}) → core::Object*; -> core::Iterable::firstWhere
+  abstract member-signature method lastWhere((core::Object*) →* core::bool* test, {covariant-by-class () →* core::Object* orElse = #C3}) → core::Object*; -> core::Iterable::lastWhere
+  abstract member-signature method singleWhere((core::Object*) →* core::bool* test, {covariant-by-class () →* core::Object* orElse = #C3}) → core::Object*; -> core::Iterable::singleWhere
+  abstract member-signature method elementAt(core::int* index) → core::Object*; -> core::Iterable::elementAt
+  abstract member-signature method toString() → core::String*; -> core::Iterable::toString
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature get iterator() → core::Iterator<core::Object*>*; -> core::Iterable::iterator
+}
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/sdk_diagnostic.dart:12:8: Error: Too few positional arguments: 1 required, 0 given.
+  print(incorrectArgument: \"fisk\");
+       ^";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = ""
+  #C2 = true
+  #C3 = null
+}
diff --git a/pkg/front_end/testcases/general/spread_collection.dart.weak.modular.expect b/pkg/front_end/testcases/general/spread_collection.dart.weak.modular.expect
new file mode 100644
index 0000000..6948e05
--- /dev/null
+++ b/pkg/front_end/testcases/general/spread_collection.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/spread_collection.dart:21:21: Error: Not enough type information to disambiguate between literal set and literal map.
+// Try providing type arguments for the literal explicitly to disambiguate it.
+//   final aSetOrMap = {...foo()};
+//                     ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+static method main() → dynamic {
+  final core::List<core::int*>* aList = block {
+    final core::List<core::int*>* #t1 = <core::int*>[1];
+    #t1.{core::List::addAll}{Invariant}(<core::int*>[2]){(core::Iterable<core::int*>*) →* void};
+    final core::Iterable<core::int*>* #t2 = <core::int*>[3];
+    if(!(#t2 == null))
+      #t1.{core::List::addAll}{Invariant}(#t2){(core::Iterable<core::int*>*) →* void};
+  } =>#t1;
+  final core::Map<core::int*, core::int*>* aMap = block {
+    final core::Map<core::int*, core::int*>* #t3 = <core::int*, core::int*>{};
+    #t3.{core::Map::[]=}{Invariant}(1, 1){(core::int*, core::int*) →* void};
+    for (final core::MapEntry<core::int*, core::int*>* #t4 in <core::int*, core::int*>{2: 2}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int*, core::int*>>})
+      #t3.{core::Map::[]=}{Invariant}(#t4.{core::MapEntry::key}{core::int*}, #t4.{core::MapEntry::value}{core::int*}){(core::int*, core::int*) →* void};
+    final core::Map<core::int*, core::int*>* #t5 = <core::int*, core::int*>{3: 3};
+    if(!(#t5 == null))
+      for (final core::MapEntry<core::int*, core::int*>* #t6 in #t5.{core::Map::entries}{core::Iterable<core::MapEntry<core::int*, core::int*>>})
+        #t3.{core::Map::[]=}{Invariant}(#t6.{core::MapEntry::key}{core::int*}, #t6.{core::MapEntry::value}{core::int*}){(core::int*, core::int*) →* void};
+  } =>#t3;
+  final core::Set<core::int*>* aSet = block {
+    final core::Set<core::int*>* #t7 = col::LinkedHashSet::•<core::int*>();
+    #t7.{core::Set::add}{Invariant}(1){(core::int*) →* core::bool*};
+    #t7.{core::Set::addAll}{Invariant}(<core::int*>[2]){(core::Iterable<core::int*>*) →* void};
+    final core::Iterable<core::int*>* #t8 = <core::int*>[3];
+    if(!(#t8 == null))
+      #t7.{core::Set::addAll}{Invariant}(#t8){(core::Iterable<core::int*>*) →* void};
+  } =>#t7;
+  final Never* aSetOrMap = invalid-expression "pkg/front_end/testcases/general/spread_collection.dart:21:21: Error: Not enough type information to disambiguate between literal set and literal map.
+Try providing type arguments for the literal explicitly to disambiguate it.
+  final aSetOrMap = {...foo()};
+                    ^";
+  core::print(aList);
+  core::print(aSet);
+  core::print(aMap);
+}
+static method foo() → dynamic
+  return null;
diff --git a/pkg/front_end/testcases/general/spread_collection_inference.dart.weak.modular.expect b/pkg/front_end/testcases/general/spread_collection_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..470fbda
--- /dev/null
+++ b/pkg/front_end/testcases/general/spread_collection_inference.dart.weak.modular.expect
@@ -0,0 +1,376 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:64:28: Error: Not enough type information to disambiguate between literal set and literal map.
+// Try providing type arguments for the literal explicitly to disambiguate it.
+//   dynamic map21ambiguous = {...(mapSpread as dynamic)};
+//                            ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:96:28: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+//   dynamic map24ambiguous = {...spread, ...mapSpread};
+//                            ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:98:36: Error: A value of type 'List<int>' can't be assigned to a variable of type 'int'.
+//  - 'List' is from 'dart:core'.
+//   int lhs30 = /*@ typeArgs=int* */ [...spread];
+//                                    ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:100:36: Error: A value of type 'Set<int>' can't be assigned to a variable of type 'int'.
+//  - 'Set' is from 'dart:core'.
+//   int set30 = /*@ typeArgs=int* */ {...spread, 42};
+//                                    ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:103:7: Error: A value of type 'Set<int>' can't be assigned to a variable of type 'int'.
+//  - 'Set' is from 'dart:core'.
+//       {...spread};
+//       ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:106:7: Error: A value of type 'Map<String, int>' can't be assigned to a variable of type 'int'.
+//  - 'Map' is from 'dart:core'.
+//       {...mapSpread, "baz": 42};
+//       ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:109:7: Error: A value of type 'Map<String, int>' can't be assigned to a variable of type 'int'.
+//  - 'Map' is from 'dart:core'.
+//       {...mapSpread};
+//       ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:111:38: Error: Unexpected type 'int' of a spread.  Expected 'dynamic' or an Iterable.
+//   List<dynamic> lhs40 = <dynamic>[...notSpreadInt];
+//                                      ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:113:37: Error: Unexpected type 'int' of a spread.  Expected 'dynamic' or an Iterable.
+//   Set<dynamic> set40 = <dynamic>{...notSpreadInt};
+//                                     ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:115:55: Error: Unexpected type 'int' of a map spread entry.  Expected 'dynamic' or a Map.
+//   Map<dynamic, dynamic> map40 = <dynamic, dynamic>{...notSpreadInt};
+//                                                       ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:117:38: Error: Unexpected type 'int Function()' of a spread.  Expected 'dynamic' or an Iterable.
+//   List<dynamic> lhs50 = <dynamic>[...notSpreadFunction];
+//                                      ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:119:37: Error: Unexpected type 'int Function()' of a spread.  Expected 'dynamic' or an Iterable.
+//   Set<dynamic> set50 = <dynamic>{...notSpreadFunction};
+//                                     ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:121:55: Error: Unexpected type 'int Function()' of a map spread entry.  Expected 'dynamic' or a Map.
+//   Map<dynamic, dynamic> map50 = <dynamic, dynamic>{...notSpreadFunction};
+//                                                       ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:123:36: Error: Can't assign spread elements of type 'int' to collection elements of type 'String'.
+//   List<String> lhs60 = <String>[...spread];
+//                                    ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:125:35: Error: Can't assign spread elements of type 'int' to collection elements of type 'String'.
+//   Set<String> set60 = <String>{...spread};
+//                                   ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:127:39: Error: Can't assign spread entry keys of type 'String' to map entry keys of type 'int'.
+//   Map<int, int> map60 = <int, int>{...mapSpread};
+//                                       ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:129:51: Error: Can't assign spread entry values of type 'int' to map entry values of type 'String'.
+//   Map<String, String> map61 = <String, String>{...mapSpread};
+//                                                   ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:131:30: Error: Can't spread a value with static type 'Null'.
+//   List<int> lhs70 = <int>[...null];
+//                              ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:133:29: Error: Can't spread a value with static type 'Null'.
+//   Set<int> set70 = <int>{...null};
+//                             ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:137:8: Error: Can't spread a value with static type 'Null'.
+//     ...null,
+//        ^
+//
+// pkg/front_end/testcases/general/spread_collection_inference.dart:142:45: Error: Can't spread a value with static type 'Null'.
+//   Map<String, int> map70 = <String, int>{...null};
+//                                             ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+static method bar<K extends core::Object* = dynamic, V extends core::Object* = dynamic>() → core::Map<self::bar::K*, self::bar::V*>*
+  return null;
+static method foo(dynamic dynVar) → dynamic {
+  core::List<core::int*>* spread = <core::int*>[1, 2, 3];
+  core::Map<core::String*, core::int*>* mapSpread = <core::String*, core::int*>{"foo": 4, "bar": 2};
+  core::int* notSpreadInt = 42;
+  () →* core::int* notSpreadFunction = null;
+  core::Map<core::int*, core::num*>* mapIntNum = <core::int*, core::num*>{42: 42};
+  core::List<core::num*>* listNum = <core::num*>[42];
+  core::List<dynamic>* lhs10 = block {
+    final core::List<dynamic>* #t1 = core::List::of<dynamic>(<dynamic>[]);
+  } =>#t1;
+  core::Set<dynamic>* set10 = block {
+    final core::Set<dynamic>* #t2 = col::LinkedHashSet::of<dynamic>(<dynamic>[]);
+  } =>#t2;
+  core::Map<dynamic, dynamic>* map10 = block {
+    final core::Map<dynamic, dynamic>* #t3 = <dynamic, dynamic>{};
+    for (final core::MapEntry<dynamic, dynamic>* #t4 in <dynamic, dynamic>{}.{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, dynamic>>})
+      #t3.{core::Map::[]=}{Invariant}(#t4.{core::MapEntry::key}{dynamic}, #t4.{core::MapEntry::value}{dynamic}){(dynamic, dynamic) →* void};
+  } =>#t3;
+  core::Map<dynamic, dynamic>* map10ambiguous = block {
+    final core::Map<dynamic, dynamic>* #t5 = <dynamic, dynamic>{};
+    for (final core::MapEntry<dynamic, dynamic>* #t6 in <dynamic, dynamic>{}.{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, dynamic>>})
+      #t5.{core::Map::[]=}{Invariant}(#t6.{core::MapEntry::key}{dynamic}, #t6.{core::MapEntry::value}{dynamic}){(dynamic, dynamic) →* void};
+  } =>#t5;
+  core::List<core::int*>* lhs20 = block {
+    final core::List<core::int*>* #t7 = core::List::of<core::int*>(spread);
+  } =>#t7;
+  core::Set<core::int*>* set20 = block {
+    final core::Set<core::int*>* #t8 = col::LinkedHashSet::of<core::int*>(spread);
+    #t8.{core::Set::add}{Invariant}(42){(core::int*) →* core::bool*};
+  } =>#t8;
+  core::Set<core::int*>* set20ambiguous = block {
+    final core::Set<core::int*>* #t9 = col::LinkedHashSet::•<core::int*>();
+    for (final dynamic #t10 in spread) {
+      final core::int* #t11 = #t10 as{TypeError} core::int*;
+      #t9.{core::Set::add}{Invariant}(#t11){(core::int*) →* core::bool*};
+    }
+  } =>#t9;
+  core::Map<core::String*, core::int*>* map20 = block {
+    final core::Map<core::String*, core::int*>* #t12 = <core::String*, core::int*>{};
+    for (final core::MapEntry<core::String*, core::int*>* #t13 in mapSpread.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>})
+      #t12.{core::Map::[]=}{Invariant}(#t13.{core::MapEntry::key}{core::String*}, #t13.{core::MapEntry::value}{core::int*}){(core::String*, core::int*) →* void};
+    #t12.{core::Map::[]=}{Invariant}("baz", 42){(core::String*, core::int*) →* void};
+  } =>#t12;
+  core::Map<core::String*, core::int*>* map20ambiguous = block {
+    final core::Map<core::String*, core::int*>* #t14 = <core::String*, core::int*>{};
+    for (final core::MapEntry<core::String*, core::int*>* #t15 in mapSpread.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>})
+      #t14.{core::Map::[]=}{Invariant}(#t15.{core::MapEntry::key}{core::String*}, #t15.{core::MapEntry::value}{core::int*}){(core::String*, core::int*) →* void};
+  } =>#t14;
+  core::List<dynamic>* lhs21 = block {
+    final core::List<dynamic>* #t16 = core::List::of<dynamic>((spread as dynamic) as{TypeError,ForDynamic} core::Iterable<dynamic>*);
+  } =>#t16;
+  core::Set<dynamic>* set21 = block {
+    final core::Set<dynamic>* #t17 = col::LinkedHashSet::of<dynamic>((spread as dynamic) as{TypeError,ForDynamic} core::Iterable<dynamic>*);
+    #t17.{core::Set::add}{Invariant}(42){(dynamic) →* core::bool*};
+  } =>#t17;
+  core::Map<dynamic, dynamic>* map21 = block {
+    final core::Map<dynamic, dynamic>* #t18 = <dynamic, dynamic>{};
+    for (final core::MapEntry<dynamic, dynamic>* #t19 in ((mapSpread as dynamic) as{TypeError,ForDynamic} core::Map<dynamic, dynamic>*).{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, dynamic>>})
+      #t18.{core::Map::[]=}{Invariant}(#t19.{core::MapEntry::key}{dynamic}, #t19.{core::MapEntry::value}{dynamic}){(dynamic, dynamic) →* void};
+    #t18.{core::Map::[]=}{Invariant}("baz", 42){(dynamic, dynamic) →* void};
+  } =>#t18;
+  dynamic map21ambiguous = invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:64:28: Error: Not enough type information to disambiguate between literal set and literal map.
+Try providing type arguments for the literal explicitly to disambiguate it.
+  dynamic map21ambiguous = {...(mapSpread as dynamic)};
+                           ^";
+  core::List<core::int*>* lhs22 = block {
+    final core::List<core::int*>* #t20 = core::List::of<core::int*>(<core::int*>[]);
+  } =>#t20;
+  core::Set<core::int*>* set22 = block {
+    final core::Set<core::int*>* #t21 = col::LinkedHashSet::of<core::int*>(<core::int*>[]);
+    #t21.{core::Set::add}{Invariant}(42){(core::int*) →* core::bool*};
+  } =>#t21;
+  core::Set<core::int*>* set22ambiguous = block {
+    final core::Set<core::int*>* #t22 = col::LinkedHashSet::•<core::int*>();
+    for (final dynamic #t23 in <core::int*>[]) {
+      final core::int* #t24 = #t23 as{TypeError} core::int*;
+      #t22.{core::Set::add}{Invariant}(#t24){(core::int*) →* core::bool*};
+    }
+  } =>#t22;
+  core::Map<core::String*, core::int*>* map22 = block {
+    final core::Map<core::String*, core::int*>* #t25 = <core::String*, core::int*>{};
+    for (final core::MapEntry<core::String*, core::int*>* #t26 in <core::String*, core::int*>{}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>})
+      #t25.{core::Map::[]=}{Invariant}(#t26.{core::MapEntry::key}{core::String*}, #t26.{core::MapEntry::value}{core::int*}){(core::String*, core::int*) →* void};
+  } =>#t25;
+  core::List<core::List<core::int*>*>* lhs23 = block {
+    final core::List<core::List<core::int*>*>* #t27 = core::List::of<core::List<core::int*>*>(<core::List<core::int*>*>[<core::int*>[]]);
+  } =>#t27;
+  core::Set<core::List<core::int*>*>* set23 = block {
+    final core::Set<core::List<core::int*>*>* #t28 = col::LinkedHashSet::of<core::List<core::int*>*>(<core::List<core::int*>*>[<core::int*>[]]);
+    #t28.{core::Set::add}{Invariant}(<core::int*>[42]){(core::List<core::int*>*) →* core::bool*};
+  } =>#t28;
+  core::Set<core::List<core::int*>*>* set23ambiguous = block {
+    final core::Set<core::List<core::int*>*>* #t29 = col::LinkedHashSet::•<core::List<core::int*>*>();
+    for (final dynamic #t30 in <core::List<core::int*>*>[<core::int*>[]]) {
+      final core::List<core::int*>* #t31 = #t30 as{TypeError} core::List<core::int*>*;
+      #t29.{core::Set::add}{Invariant}(#t31){(core::List<core::int*>*) →* core::bool*};
+    }
+  } =>#t29;
+  core::Map<core::String*, core::List<core::int*>*>* map23 = block {
+    final core::Map<core::String*, core::List<core::int*>*>* #t32 = <core::String*, core::List<core::int*>*>{};
+    for (final core::MapEntry<core::String*, core::List<core::int*>*>* #t33 in <core::String*, core::List<core::int*>*>{"baz": <core::int*>[]}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::List<core::int*>*>>})
+      #t32.{core::Map::[]=}{Invariant}(#t33.{core::MapEntry::key}{core::String*}, #t33.{core::MapEntry::value}{core::List<core::int*>*}){(core::String*, core::List<core::int*>*) →* void};
+  } =>#t32;
+  dynamic map24ambiguous = invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:96:28: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+  dynamic map24ambiguous = {...spread, ...mapSpread};
+                           ^";
+  core::int* lhs30 = invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:98:36: Error: A value of type 'List<int>' can't be assigned to a variable of type 'int'.
+ - 'List' is from 'dart:core'.
+  int lhs30 = /*@ typeArgs=int* */ [...spread];
+                                   ^" in ( block {
+    final core::List<core::int*>* #t34 = core::List::of<core::int*>(spread);
+  } =>#t34) as{TypeError} core::int*;
+  core::int* set30 = invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:100:36: Error: A value of type 'Set<int>' can't be assigned to a variable of type 'int'.
+ - 'Set' is from 'dart:core'.
+  int set30 = /*@ typeArgs=int* */ {...spread, 42};
+                                   ^" in ( block {
+    final core::Set<core::int*>* #t35 = col::LinkedHashSet::of<core::int*>(spread);
+    #t35.{core::Set::add}{Invariant}(42){(core::int*) →* core::bool*};
+  } =>#t35) as{TypeError} core::int*;
+  core::int* set30ambiguous = invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:103:7: Error: A value of type 'Set<int>' can't be assigned to a variable of type 'int'.
+ - 'Set' is from 'dart:core'.
+      {...spread};
+      ^" in ( block {
+    final core::Set<core::int*>* #t36 = col::LinkedHashSet::•<core::int*>();
+    for (final dynamic #t37 in spread) {
+      final core::int* #t38 = #t37 as{TypeError} core::int*;
+      #t36.{core::Set::add}{Invariant}(#t38){(core::int*) →* core::bool*};
+    }
+  } =>#t36) as{TypeError} core::int*;
+  core::int* map30 = invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:106:7: Error: A value of type 'Map<String, int>' can't be assigned to a variable of type 'int'.
+ - 'Map' is from 'dart:core'.
+      {...mapSpread, \"baz\": 42};
+      ^" in ( block {
+    final core::Map<core::String*, core::int*>* #t39 = <core::String*, core::int*>{};
+    for (final core::MapEntry<core::String*, core::int*>* #t40 in mapSpread.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>})
+      #t39.{core::Map::[]=}{Invariant}(#t40.{core::MapEntry::key}{core::String*}, #t40.{core::MapEntry::value}{core::int*}){(core::String*, core::int*) →* void};
+    #t39.{core::Map::[]=}{Invariant}("baz", 42){(core::String*, core::int*) →* void};
+  } =>#t39) as{TypeError} core::int*;
+  core::int* map30ambiguous = invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:109:7: Error: A value of type 'Map<String, int>' can't be assigned to a variable of type 'int'.
+ - 'Map' is from 'dart:core'.
+      {...mapSpread};
+      ^" in ( block {
+    final core::Map<core::String*, core::int*>* #t41 = <core::String*, core::int*>{};
+    for (final core::MapEntry<core::String*, core::int*>* #t42 in mapSpread.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>})
+      #t41.{core::Map::[]=}{Invariant}(#t42.{core::MapEntry::key}{core::String*}, #t42.{core::MapEntry::value}{core::int*}){(core::String*, core::int*) →* void};
+  } =>#t41) as{TypeError} core::int*;
+  core::List<dynamic>* lhs40 = <dynamic>[invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:111:38: Error: Unexpected type 'int' of a spread.  Expected 'dynamic' or an Iterable.
+  List<dynamic> lhs40 = <dynamic>[...notSpreadInt];
+                                     ^"];
+  core::Set<dynamic>* set40 = block {
+    final core::Set<dynamic>* #t43 = col::LinkedHashSet::•<dynamic>();
+    #t43.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:113:37: Error: Unexpected type 'int' of a spread.  Expected 'dynamic' or an Iterable.
+  Set<dynamic> set40 = <dynamic>{...notSpreadInt};
+                                    ^"){(dynamic) →* core::bool*};
+  } =>#t43;
+  core::Map<dynamic, dynamic>* map40 = <dynamic, dynamic>{invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:115:55: Error: Unexpected type 'int' of a map spread entry.  Expected 'dynamic' or a Map.
+  Map<dynamic, dynamic> map40 = <dynamic, dynamic>{...notSpreadInt};
+                                                      ^": null};
+  core::List<dynamic>* lhs50 = <dynamic>[invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:117:38: Error: Unexpected type 'int Function()' of a spread.  Expected 'dynamic' or an Iterable.
+  List<dynamic> lhs50 = <dynamic>[...notSpreadFunction];
+                                     ^"];
+  core::Set<dynamic>* set50 = block {
+    final core::Set<dynamic>* #t44 = col::LinkedHashSet::•<dynamic>();
+    #t44.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:119:37: Error: Unexpected type 'int Function()' of a spread.  Expected 'dynamic' or an Iterable.
+  Set<dynamic> set50 = <dynamic>{...notSpreadFunction};
+                                    ^"){(dynamic) →* core::bool*};
+  } =>#t44;
+  core::Map<dynamic, dynamic>* map50 = <dynamic, dynamic>{invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:121:55: Error: Unexpected type 'int Function()' of a map spread entry.  Expected 'dynamic' or a Map.
+  Map<dynamic, dynamic> map50 = <dynamic, dynamic>{...notSpreadFunction};
+                                                      ^": null};
+  core::List<core::String*>* lhs60 = <core::String*>[invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:123:36: Error: Can't assign spread elements of type 'int' to collection elements of type 'String'.
+  List<String> lhs60 = <String>[...spread];
+                                   ^"];
+  core::Set<core::String*>* set60 = block {
+    final core::Set<core::String*>* #t45 = col::LinkedHashSet::•<core::String*>();
+    #t45.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:125:35: Error: Can't assign spread elements of type 'int' to collection elements of type 'String'.
+  Set<String> set60 = <String>{...spread};
+                                  ^"){(core::String*) →* core::bool*};
+  } =>#t45;
+  core::Map<core::int*, core::int*>* map60 = <core::int*, core::int*>{invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:127:39: Error: Can't assign spread entry keys of type 'String' to map entry keys of type 'int'.
+  Map<int, int> map60 = <int, int>{...mapSpread};
+                                      ^": null};
+  core::Map<core::String*, core::String*>* map61 = <core::String*, core::String*>{null: invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:129:51: Error: Can't assign spread entry values of type 'int' to map entry values of type 'String'.
+  Map<String, String> map61 = <String, String>{...mapSpread};
+                                                  ^"};
+  core::List<core::int*>* lhs70 = <core::int*>[invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:131:30: Error: Can't spread a value with static type 'Null'.
+  List<int> lhs70 = <int>[...null];
+                             ^"];
+  core::Set<core::int*>* set70 = block {
+    final core::Set<core::int*>* #t46 = col::LinkedHashSet::•<core::int*>();
+    #t46.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:133:29: Error: Can't spread a value with static type 'Null'.
+  Set<int> set70 = <int>{...null};
+                            ^"){(core::int*) →* core::bool*};
+  } =>#t46;
+  core::Set<dynamic>* set71ambiguous = block {
+    final core::Set<dynamic>* #t47 = col::LinkedHashSet::•<dynamic>();
+    #t47.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:137:8: Error: Can't spread a value with static type 'Null'.
+    ...null,
+       ^"){(dynamic) →* core::bool*};
+    for (final dynamic #t48 in <dynamic>[]) {
+      final dynamic #t49 = #t48 as{TypeError} dynamic;
+      #t47.{core::Set::add}{Invariant}(#t49){(dynamic) →* core::bool*};
+    }
+  } =>#t47;
+  core::Map<core::String*, core::int*>* map70 = <core::String*, core::int*>{invalid-expression "pkg/front_end/testcases/general/spread_collection_inference.dart:142:45: Error: Can't spread a value with static type 'Null'.
+  Map<String, int> map70 = <String, int>{...null};
+                                            ^": null};
+  core::List<core::int*>* lhs80 = block {
+    final core::List<core::int*>* #t50 = <core::int*>[];
+    final core::Iterable<core::int*>* #t51 = null;
+    if(!(#t51 == null))
+      #t50.{core::List::addAll}{Invariant}(#t51){(core::Iterable<core::int*>*) →* void};
+  } =>#t50;
+  core::Set<core::int*>* set80 = block {
+    final core::Set<core::int*>* #t52 = col::LinkedHashSet::•<core::int*>();
+    final core::Iterable<core::int*>* #t53 = null;
+    if(!(#t53 == null))
+      #t52.{core::Set::addAll}{Invariant}(#t53){(core::Iterable<core::int*>*) →* void};
+  } =>#t52;
+  core::Set<dynamic>* set81ambiguous = block {
+    final core::Set<dynamic>* #t54 = col::LinkedHashSet::•<dynamic>();
+    final core::Iterable<dynamic>* #t55 = null;
+    if(!(#t55 == null))
+      for (final dynamic #t56 in #t55) {
+        final dynamic #t57 = #t56 as{TypeError} dynamic;
+        #t54.{core::Set::add}{Invariant}(#t57){(dynamic) →* core::bool*};
+      }
+    for (final dynamic #t58 in <dynamic>[]) {
+      final dynamic #t59 = #t58 as{TypeError} dynamic;
+      #t54.{core::Set::add}{Invariant}(#t59){(dynamic) →* core::bool*};
+    }
+  } =>#t54;
+  core::Map<core::String*, core::int*>* map80 = block {
+    final core::Map<core::String*, core::int*>* #t60 = <core::String*, core::int*>{};
+    final core::Map<core::String*, core::int*>* #t61 = null;
+    if(!(#t61 == null))
+      for (final core::MapEntry<core::String*, core::int*>* #t62 in #t61.{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>})
+        #t60.{core::Map::[]=}{Invariant}(#t62.{core::MapEntry::key}{core::String*}, #t62.{core::MapEntry::value}{core::int*}){(core::String*, core::int*) →* void};
+  } =>#t60;
+  core::Map<core::String*, core::int*>* map90 = block {
+    final core::Map<core::String*, core::int*>* #t63 = <core::String*, core::int*>{};
+    for (final core::MapEntry<core::String*, core::int*>* #t64 in self::bar<core::String*, core::int*>().{core::Map::entries}{core::Iterable<core::MapEntry<core::String*, core::int*>>})
+      #t63.{core::Map::[]=}{Invariant}(#t64.{core::MapEntry::key}{core::String*}, #t64.{core::MapEntry::value}{core::int*}){(core::String*, core::int*) →* void};
+  } =>#t63;
+  core::List<core::int*>* list100 = block {
+    final core::List<core::int*>* #t65 = <core::int*>[];
+    for (final dynamic #t66 in listNum) {
+      final core::int* #t67 = #t66 as{TypeError} core::int*;
+      #t65.{core::List::add}{Invariant}(#t67){(core::int*) →* void};
+    }
+  } =>#t65;
+  core::Map<core::num*, core::int*>* map100 = block {
+    final core::Map<core::num*, core::int*>* #t68 = <core::num*, core::int*>{};
+    for (final core::MapEntry<dynamic, dynamic>* #t69 in mapIntNum.{core::Map::entries}{core::Iterable<core::MapEntry<core::num*, core::int*>>}) {
+      final core::num* #t70 = #t69.{core::MapEntry::key}{dynamic} as{TypeError} core::num*;
+      final core::int* #t71 = #t69.{core::MapEntry::value}{dynamic} as{TypeError} core::int*;
+      #t68.{core::Map::[]=}{Invariant}(#t70, #t71){(core::num*, core::int*) →* void};
+    }
+  } =>#t68;
+  core::List<core::int*>* list110 = block {
+    final core::List<core::int*>* #t72 = <core::int*>[];
+    for (final dynamic #t73 in dynVar as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      final core::int* #t74 = #t73 as{TypeError} core::int*;
+      #t72.{core::List::add}{Invariant}(#t74){(core::int*) →* void};
+    }
+  } =>#t72;
+  core::Map<core::num*, core::int*>* map110 = block {
+    final core::Map<core::num*, core::int*>* #t75 = <core::num*, core::int*>{};
+    for (final core::MapEntry<dynamic, dynamic>* #t76 in (dynVar as{TypeError,ForDynamic} core::Map<dynamic, dynamic>*).{core::Map::entries}{core::Iterable<core::MapEntry<core::num*, core::int*>>}) {
+      final core::num* #t77 = #t76.{core::MapEntry::key}{dynamic} as{TypeError} core::num*;
+      final core::int* #t78 = #t76.{core::MapEntry::value}{dynamic} as{TypeError} core::int*;
+      #t75.{core::Map::[]=}{Invariant}(#t77, #t78){(core::num*, core::int*) →* void};
+    }
+  } =>#t75;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/statements.dart.weak.modular.expect b/pkg/front_end/testcases/general/statements.dart.weak.modular.expect
new file mode 100644
index 0000000..8d3c256
--- /dev/null
+++ b/pkg/front_end/testcases/general/statements.dart.weak.modular.expect
@@ -0,0 +1,159 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+static method foo() → dynamic {
+  try {
+    return;
+  }
+  finally {
+    core::print("Hello from finally block!");
+  }
+}
+static method bar(dynamic d) → dynamic async* {
+  await for (dynamic x in d as{TypeError,ForDynamic} asy::Stream<dynamic>*) {
+    yield x;
+    yield* x as{TypeError,ForDynamic} asy::Stream<dynamic>*;
+  }
+}
+static method main() → dynamic {
+  do {
+    core::print("Hello from do-while!");
+  }
+  while (false)
+  do {
+    void x = core::print("Hello from do-while!");
+  }
+  while (false)
+  for (core::String* s in <core::String*>["Hello from for-in!"]) {
+    core::print(s);
+  }
+  for (core::String* s in <core::String*>["Hello from for-in without block!"])
+    core::print(s);
+  dynamic s;
+  for (final dynamic #t1 in <dynamic>["Hello from for-in without decl!"]) {
+    s = #t1;
+    core::print(s);
+  }
+  for (final dynamic #t2 in <dynamic>["Hello from for-in without decl and block!"]) {
+    s = #t2;
+    core::print(s);
+  }
+  core::print("Hello from labeled statement!");
+  try {
+    try {
+      throw "Hello from rethrow!";
+    }
+    on dynamic catch(final dynamic e) {
+      rethrow;
+    }
+  }
+  on dynamic catch(final dynamic e) {
+    core::print(e);
+  }
+  self::foo();
+  core::bool* done = false;
+  while (!done) {
+    done = true;
+    core::print("Hello from while!");
+  }
+  ;
+  assert(true);
+  assert(true, "Hello from assert!");
+  try {
+    assert(false, "Hello from assert!");
+  }
+  on dynamic catch(final dynamic e) {
+    core::print(e);
+  }
+  #L1:
+  switch(1) {
+    #L2:
+    case #C1:
+    case #C2:
+      {
+        core::print("Hello from switch case!");
+        break #L1;
+      }
+    #L3:
+    default:
+      {
+        break #L1;
+      }
+  }
+  #L4:
+  switch(4) {
+    #L5:
+    case #C2:
+      {
+        core::print("Hello from case 2!");
+        break #L4;
+      }
+    #L6:
+    case #C1:
+      {
+        core::print("Hello from case 1!");
+        continue #L5;
+      }
+    #L7:
+    case #C3:
+      {
+        core::print("Hello from case 0!");
+        continue #L6;
+      }
+    #L8:
+    case #C4:
+      {
+        core::print("Hello from case 4!");
+        continue #L9;
+      }
+    #L9:
+    default:
+      {
+        continue #L7;
+      }
+  }
+  #L10:
+  switch(4) {
+    #L11:
+    case #C1:
+      {
+        core::print("Hello from next case 1");
+        break #L10;
+      }
+    #L12:
+    default:
+      {
+        continue #L11;
+      }
+  }
+  core::int* i = 0;
+  #L13:
+  do
+    #L14:
+    {
+      core::print("Hello from do-while!");
+      if((i = i.{core::num::+}(1){(core::num*) →* core::int*}).{core::num::<}(3){(core::num*) →* core::bool*})
+        break #L14;
+      break #L13;
+    }
+  while (true)
+  i = 0;
+  #L15:
+  while (true)
+    #L16:
+    {
+      core::print("Hello from while!");
+      if((i = i.{core::num::+}(1){(core::num*) →* core::int*}).{core::num::<}(3){(core::num*) →* core::bool*})
+        break #L16;
+      break #L15;
+    }
+}
+
+constants  {
+  #C1 = 1
+  #C2 = 2
+  #C3 = 0
+  #C4 = 4
+}
diff --git a/pkg/front_end/testcases/general/static_setter.dart.weak.modular.expect b/pkg/front_end/testcases/general/static_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..33c8de3
--- /dev/null
+++ b/pkg/front_end/testcases/general/static_setter.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static set foo(dynamic x) → void {}
+static method main() → dynamic {
+  self::foo = new self::Foo::•();
+}
diff --git a/pkg/front_end/testcases/general/store_load.dart.weak.modular.expect b/pkg/front_end/testcases/general/store_load.dart.weak.modular.expect
new file mode 100644
index 0000000..b5b20a2
--- /dev/null
+++ b/pkg/front_end/testcases/general/store_load.dart.weak.modular.expect
@@ -0,0 +1,76 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  field dynamic _field = null;
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class FooValue extends core::Object {
+  synthetic constructor •() → self::FooValue*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar extends core::Object {
+  field dynamic _field = null;
+  synthetic constructor •() → self::Bar*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class BarValue extends core::Object {
+  synthetic constructor •() → self::BarValue*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::Foo* foo = new self::Foo::•();
+  foo.{self::Foo::_field} = new self::FooValue::•();
+  dynamic fooValue = foo.{self::Foo::_field}{dynamic};
+  core::print(fooValue);
+  self::Bar* bar = new self::Bar::•();
+  bar.{self::Bar::_field} = new self::BarValue::•();
+  dynamic barValue = bar.{self::Bar::_field}{dynamic};
+  core::print(barValue);
+}
diff --git a/pkg/front_end/testcases/general/stream_future.dart.weak.modular.expect b/pkg/front_end/testcases/general/stream_future.dart.weak.modular.expect
new file mode 100644
index 0000000..2914b7b
--- /dev/null
+++ b/pkg/front_end/testcases/general/stream_future.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/stream_future.dart:18:9: Error: A value of type 'Future<dynamic>' can't be assigned to a variable of type 'FutureOr<Class>'.
+//  - 'Future' is from 'dart:async'.
+//  - 'Class' is from 'pkg/front_end/testcases/general/stream_future.dart'.
+//   yield returnFutureDynamic();
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method returnDynamic() → dynamic
+  return new self::Class::•();
+static method returnClass() → self::Class*
+  return new self::Class::•();
+static method returnFutureDynamic() → asy::Future<dynamic>* async 
+  return new self::Class::•();
+static method returnFutureClass() → asy::Future<self::Class*>* async 
+  return new self::Class::•();
+static method error() → asy::Stream<FutureOr<self::Class*>*>* async* {
+  yield invalid-expression "pkg/front_end/testcases/general/stream_future.dart:18:9: Error: A value of type 'Future<dynamic>' can't be assigned to a variable of type 'FutureOr<Class>'.
+ - 'Future' is from 'dart:async'.
+ - 'Class' is from 'pkg/front_end/testcases/general/stream_future.dart'.
+  yield returnFutureDynamic();
+        ^" in self::returnFutureDynamic() as{TypeError} FutureOr<self::Class*>*;
+}
+static method stream() → asy::Stream<FutureOr<self::Class*>*>* async* {
+  yield self::returnDynamic() as{TypeError,ForDynamic} FutureOr<self::Class*>*;
+  yield self::returnClass();
+  yield self::returnFutureClass();
+}
+static method main() → dynamic async {
+  await for (FutureOr<self::Class*>* cls in self::stream()) {
+    core::print(cls);
+  }
+}
diff --git a/pkg/front_end/testcases/general/stringliteral.dart.weak.modular.expect b/pkg/front_end/testcases/general/stringliteral.dart.weak.modular.expect
new file mode 100644
index 0000000..2d193f7
--- /dev/null
+++ b/pkg/front_end/testcases/general/stringliteral.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static field core::String color = "brown";
+static field core::String thing = "lazy dog";
+static field core::String phrase = "The quick ${self::color} fox
+jumped over the ${self::thing}.
+";
+static field core::String adjacent = "${self::color}${self::color}${self::color}";
+static field core::String linebreaks = "${self::color}
+${self::color}
+${self::color}";
+static field core::String other = "${self::color}
+ is 
+${self::color}";
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/super_access_in_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/general/super_access_in_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..651a9c4
--- /dev/null
+++ b/pkg/front_end/testcases/general/super_access_in_initializer.dart.weak.modular.expect
@@ -0,0 +1,58 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/super_access_in_initializer.dart:15:16: Error: Undefined name 'property'.
+//       : assert(property),
+//                ^^^^^^^^
+//
+// pkg/front_end/testcases/general/super_access_in_initializer.dart:16:22: Error: Undefined name 'property'.
+//         this.field = property,
+//                      ^^^^^^^^
+//
+// pkg/front_end/testcases/general/super_access_in_initializer.dart:17:15: Error: Undefined name 'property'.
+//         super(property);
+//               ^^^^^^^^
+//
+// pkg/front_end/testcases/general/super_access_in_initializer.dart:19:27: Error: Undefined name 'property'.
+//   Class.redirect() : this(property);
+//                           ^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  constructor •(core::bool* value) → self::Super*
+    : super core::Object::•()
+    ;
+  get property() → core::bool*
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class extends self::Super {
+  field core::bool* field;
+  constructor •(core::bool* value) → self::Class*
+    : assert(invalid-expression "pkg/front_end/testcases/general/super_access_in_initializer.dart:15:16: Error: Undefined name 'property'.
+      : assert(property),
+               ^^^^^^^^"), self::Class::field = invalid-expression "pkg/front_end/testcases/general/super_access_in_initializer.dart:16:22: Error: Undefined name 'property'.
+        this.field = property,
+                     ^^^^^^^^", super self::Super::•(invalid-expression "pkg/front_end/testcases/general/super_access_in_initializer.dart:17:15: Error: Undefined name 'property'.
+        super(property);
+              ^^^^^^^^")
+    ;
+  constructor redirect() → self::Class*
+    : this self::Class::•(invalid-expression "pkg/front_end/testcases/general/super_access_in_initializer.dart:19:27: Error: Undefined name 'property'.
+  Class.redirect() : this(property);
+                          ^^^^^^^^")
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/super_call.dart.weak.modular.expect b/pkg/front_end/testcases/general/super_call.dart.weak.modular.expect
new file mode 100644
index 0000000..1e7e27c
--- /dev/null
+++ b/pkg/front_end/testcases/general/super_call.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method call(core::int* x) → core::int*
+    return x.{core::num::*}(2){(core::num*) →* core::int*};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  method call(core::int* x) → core::int*
+    return x.{core::num::*}(3){(core::num*) →* core::int*};
+  method call_super() → core::int* {
+    return super.{self::A::call}(5);
+  }
+}
+static method main() → dynamic {
+  assert(new self::B::•().{self::B::call_super}(){() →* core::int*} =={core::num::==}{(core::Object*) →* core::bool*} 10);
+}
diff --git a/pkg/front_end/testcases/general/super_nsm.dart.weak.modular.expect b/pkg/front_end/testcases/general/super_nsm.dart.weak.modular.expect
new file mode 100644
index 0000000..671d437
--- /dev/null
+++ b/pkg/front_end/testcases/general/super_nsm.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  abstract method interfaceMethod() → dynamic;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object implements self::I {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* _) → dynamic
+    return "C";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method interfaceMethod() → dynamic
+    return this.{self::C::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} dynamic;
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method noSuchMethod(core::Invocation* _) → dynamic
+    return "D";
+  method dMethod() → dynamic
+    return super.{self::C::interfaceMethod}();
+}
+static method main() → dynamic {
+  dynamic result = new self::D::•().{self::D::dMethod}(){() →* dynamic};
+  if(!(result =={core::Object::==}{(core::Object*) →* core::bool*} "D"))
+    throw "Expected 'D' but got: '${result}'";
+}
+
+constants  {
+  #C1 = #interfaceMethod
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/general/super_semi_stub.dart.weak.modular.expect b/pkg/front_end/testcases/general/super_semi_stub.dart.weak.modular.expect
new file mode 100644
index 0000000..31c108e
--- /dev/null
+++ b/pkg/front_end/testcases/general/super_semi_stub.dart.weak.modular.expect
@@ -0,0 +1,76 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/super_semi_stub.dart:17:37: Error: A value of type 'void Function(int)' can't be assigned to a variable of type 'void Function(num)'.
+//     void Function(num) sup1 = super.method; // ok
+//                                     ^
+//
+// pkg/front_end/testcases/general/super_semi_stub.dart:19:39: Error: A value of type 'void Function(int)' can't be assigned to a variable of type 'void Function(num)'.
+//     void Function(num) cls1 = Class().method; // error
+//                                       ^
+//
+// pkg/front_end/testcases/general/super_semi_stub.dart:34:14: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+//   sub.method(0.5); // error
+//              ^
+//
+// pkg/front_end/testcases/general/super_semi_stub.dart:38:14: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+//   cls.method(0.5); // error
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  method method(core::num a) → void {}
+  set setter(core::num a) → void {}
+}
+class Class extends self::Super {
+  synthetic constructor •() → self::Class
+    : super self::Super::•()
+    ;
+  forwarding-stub forwarding-semi-stub method /* signature-type: (core::int) → void */ method(covariant-by-declaration core::num a) → void
+    return super.{self::Super::method}(a);
+  forwarding-stub forwarding-semi-stub set /* signature-type: (core::int) → void */ setter(covariant-by-declaration core::num a) → void
+    return super.{self::Super::setter} = a;
+}
+class Subclass extends self::Class {
+  synthetic constructor •() → self::Subclass
+    : super self::Class::•()
+    ;
+  method method(covariant-by-declaration core::int a) → void {
+    (core::num) → void sup1 = invalid-expression "pkg/front_end/testcases/general/super_semi_stub.dart:17:37: Error: A value of type 'void Function(int)' can't be assigned to a variable of type 'void Function(num)'.
+    void Function(num) sup1 = super.method; // ok
+                                    ^" in super.{self::Class::method} as{TypeError,ForNonNullableByDefault} (core::num) → void;
+    (core::int) → void sup2 = super.{self::Class::method};
+    (core::num) → void cls1 = invalid-expression "pkg/front_end/testcases/general/super_semi_stub.dart:19:39: Error: A value of type 'void Function(int)' can't be assigned to a variable of type 'void Function(num)'.
+    void Function(num) cls1 = Class().method; // error
+                                      ^" in new self::Class::•().{self::Class::method}{(core::int) → void} as{TypeError,ForNonNullableByDefault} (core::num) → void;
+    (core::int) → void cls2 = new self::Class::•().{self::Class::method}{(core::int) → void};
+    (core::int) → void cls3 = new self::Class::•().{self::Class::method}{(core::int) → void};
+  }
+  set setter(covariant-by-declaration core::int a) → void {
+    super.{self::Class::setter} = 0;
+    super.{self::Class::setter} = 0.5;
+    new self::Class::•().{self::Class::setter} = 0;
+    new self::Class::•().{self::Class::setter} = 0.5;
+  }
+}
+static method test(self::Subclass sub) → dynamic {
+  sub.{self::Subclass::method}(0){(core::int) → void};
+  sub.{self::Subclass::method}(invalid-expression "pkg/front_end/testcases/general/super_semi_stub.dart:34:14: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+  sub.method(0.5); // error
+             ^" in 0.5 as{TypeError,ForNonNullableByDefault} core::int){(core::int) → void};
+  self::Class cls = sub;
+  cls.{self::Class::method}(0){(core::int) → void};
+  cls.{self::Class::method}(invalid-expression "pkg/front_end/testcases/general/super_semi_stub.dart:38:14: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+  cls.method(0.5); // error
+             ^" in 0.5 as{TypeError,ForNonNullableByDefault} core::int){(core::int) → void};
+  self::Super sup = sub;
+  sup.{self::Super::method}(0){(core::num) → void};
+  sup.{self::Super::method}(0.5){(core::num) → void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/super_set_abstract.dart.weak.modular.expect b/pkg/front_end/testcases/general/super_set_abstract.dart.weak.modular.expect
new file mode 100644
index 0000000..096efc9
--- /dev/null
+++ b/pkg/front_end/testcases/general/super_set_abstract.dart.weak.modular.expect
@@ -0,0 +1,47 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/super_set_abstract.dart:15:24: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     super.setter = '$o';
+//                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class SuperClass extends core::Object {
+  synthetic constructor •() → self::SuperClass*
+    : super core::Object::•()
+    ;
+  set setter(core::int* o) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Class extends self::SuperClass {
+  synthetic constructor •() → self::Class*
+    : super self::SuperClass::•()
+    ;
+  abstract set setter(core::Object* o) → void;
+}
+class SubClass extends self::Class {
+  synthetic constructor •() → self::SubClass*
+    : super self::Class::•()
+    ;
+  set setter(core::Object* o) → void {
+    super.{self::SuperClass::setter} = invalid-expression "pkg/front_end/testcases/general/super_set_abstract.dart:15:24: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    super.setter = '\$o';
+                       ^" in "${o}" as{TypeError} core::int*;
+  }
+}
+static method test() → dynamic {
+  new self::SubClass::•().{self::SubClass::setter} = "0";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/super_set_covariant.dart.weak.modular.expect b/pkg/front_end/testcases/general/super_set_covariant.dart.weak.modular.expect
new file mode 100644
index 0000000..fede2f5
--- /dev/null
+++ b/pkg/front_end/testcases/general/super_set_covariant.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class SuperClass extends core::Object {
+  synthetic constructor •() → self::SuperClass*
+    : super core::Object::•()
+    ;
+  set setter(core::Object* o) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Class extends self::SuperClass {
+  synthetic constructor •() → self::Class*
+    : super self::SuperClass::•()
+    ;
+  forwarding-stub forwarding-semi-stub set /* signature-type: (core::int*) →* void */ setter(covariant-by-declaration core::Object* o) → void
+    return super.{self::SuperClass::setter} = o;
+}
+class SubClass extends self::Class {
+  synthetic constructor •() → self::SubClass*
+    : super self::Class::•()
+    ;
+  set setter(covariant-by-declaration core::int* o) → void {
+    super.{self::Class::setter} = "${o}";
+  }
+}
+static method test() → dynamic {
+  new self::SubClass::•().{self::SubClass::setter} = 0;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/tabs.dart.weak.modular.expect b/pkg/front_end/testcases/general/tabs.dart.weak.modular.expect
new file mode 100644
index 0000000..c69fb6b
--- /dev/null
+++ b/pkg/front_end/testcases/general/tabs.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/tabs.dart:9:9: Error: Undefined name 'one'.
+//   print(one);
+//         ^^^
+//
+// pkg/front_end/testcases/general/tabs.dart:10:9: Error: Undefined name 'two'.
+//   print(two);
+//         ^^^
+//
+// pkg/front_end/testcases/general/tabs.dart:11:9: Error: Undefined name 'three'.
+//   print(three);
+//         ^^^^^
+//
+// pkg/front_end/testcases/general/tabs.dart:12:9: Error: Undefined name 'four'.
+//   print(four);
+//         ^^^^
+//
+// pkg/front_end/testcases/general/tabs.dart:13:9: Error: Undefined name 'five'.
+//   print(five);
+//         ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test() → dynamic {
+  core::print(invalid-expression "pkg/front_end/testcases/general/tabs.dart:9:9: Error: Undefined name 'one'.
+  print(one);
+        ^^^");
+  core::print(invalid-expression "pkg/front_end/testcases/general/tabs.dart:10:9: Error: Undefined name 'two'.
+  print(two);
+        ^^^");
+  core::print(invalid-expression "pkg/front_end/testcases/general/tabs.dart:11:9: Error: Undefined name 'three'.
+  print(three);
+        ^^^^^");
+  core::print(invalid-expression "pkg/front_end/testcases/general/tabs.dart:12:9: Error: Undefined name 'four'.
+  print(four);
+        ^^^^");
+  core::print(invalid-expression "pkg/front_end/testcases/general/tabs.dart:13:9: Error: Undefined name 'five'.
+  print(five);
+        ^^^^");
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/this_field_call.dart.weak.modular.expect b/pkg/front_end/testcases/general/this_field_call.dart.weak.modular.expect
new file mode 100644
index 0000000..1156174
--- /dev/null
+++ b/pkg/front_end/testcases/general/this_field_call.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  field (self::A::T*) →* void f;
+  constructor •((self::A::T*) →* void f) → self::A<self::A::T*>*
+    : self::A::f = f, super core::Object::•()
+    ;
+  method foo(covariant-by-class self::A::T* x) → dynamic
+    return let final self::A::T* #t1 = x in this.{self::A::f}{(self::A::T*) →* void}(#t1){(self::A::T*) →* void};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::A::•<core::int*>((core::int* x) → Null {}).{self::A::foo}(3){(core::int*) →* dynamic};
+}
diff --git a/pkg/front_end/testcases/general/three_typedefs_loop.dart.weak.modular.expect b/pkg/front_end/testcases/general/three_typedefs_loop.dart.weak.modular.expect
new file mode 100644
index 0000000..bd2fff9
--- /dev/null
+++ b/pkg/front_end/testcases/general/three_typedefs_loop.dart.weak.modular.expect
@@ -0,0 +1,19 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/three_typedefs_loop.dart:8:9: Error: The typedef 'Bar' has a reference to itself.
+// typedef Bar<T> = void Function(Baz<T>);
+//         ^^^
+//
+// pkg/front_end/testcases/general/three_typedefs_loop.dart:7:9: Error: The typedef 'Foo' has a reference to itself.
+// typedef Foo<T> = void Function(Bar<T>);
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef Foo<unrelated T extends core::Object* = dynamic> = invalid-type;
+typedef Bar<unrelated T extends core::Object* = dynamic> = ((invalid-type) →* void) →* void;
+typedef Baz<unrelated T extends core::Object* = dynamic> = (invalid-type) →* void;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/top_level_accessors.dart.weak.modular.expect b/pkg/front_end/testcases/general/top_level_accessors.dart.weak.modular.expect
new file mode 100644
index 0000000..9898bf6
--- /dev/null
+++ b/pkg/front_end/testcases/general/top_level_accessors.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library top_level_accessors;
+import self as self;
+import "dart:core" as core;
+
+part top_level_accessors_part.dart;
+static set /* from org-dartlang-testcase:///top_level_accessors_part.dart */ exitCode(core::int* code) → void {
+  core::print(code);
+}
+static get /* from org-dartlang-testcase:///top_level_accessors_part.dart */ exitCode() → core::int*
+  return 0;
+static method /* from org-dartlang-testcase:///top_level_accessors_part.dart */ main() → dynamic {
+  self::exitCode = 42;
+  core::print(self::exitCode);
+}
diff --git a/pkg/front_end/testcases/general/top_level_library_method.dart.weak.modular.expect b/pkg/front_end/testcases/general/top_level_library_method.dart.weak.modular.expect
new file mode 100644
index 0000000..f23119a
--- /dev/null
+++ b/pkg/front_end/testcases/general/top_level_library_method.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method library() → dynamic {
+  core::print("Hello, World!");
+}
+static method main() → dynamic
+  return self::library();
diff --git a/pkg/front_end/testcases/general/top_level_map_literal_error.dart.weak.modular.expect b/pkg/front_end/testcases/general/top_level_map_literal_error.dart.weak.modular.expect
new file mode 100644
index 0000000..d52f9e6
--- /dev/null
+++ b/pkg/front_end/testcases/general/top_level_map_literal_error.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/top_level_map_literal_error.dart:7:9: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+// var c = {...a, ...b};
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+static field core::Set<core::int> a = block {
+  final core::Set<core::int> #t1 = col::LinkedHashSet::•<core::int>();
+  #t1.{core::Set::add}{Invariant}(0){(core::int) → core::bool};
+} =>#t1;
+static field core::Map<core::int, core::int> b = <core::int, core::int>{0: 1};
+static field Never c = invalid-expression "pkg/front_end/testcases/general/top_level_map_literal_error.dart:7:9: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+var c = {...a, ...b};
+        ^";
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/top_level_variance_test.dart.weak.modular.expect b/pkg/front_end/testcases/general/top_level_variance_test.dart.weak.modular.expect
new file mode 100644
index 0000000..c61d2e4
--- /dev/null
+++ b/pkg/front_end/testcases/general/top_level_variance_test.dart.weak.modular.expect
@@ -0,0 +1,125 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef F<invariant X extends core::Object* = dynamic> = <Y extends X* = dynamic>() →* void;
+typedef Fcov<X extends core::Object* = dynamic> = () →* X*;
+typedef Fcon<contravariant X extends core::Object* = dynamic> = (X*) →* dynamic;
+typedef Finv<invariant X extends core::Object* = dynamic> = (X*) →* X*;
+typedef FcovBound<X extends core::num*> = () →* X*;
+typedef FconBound<contravariant X extends core::num*> = (X*) →* dynamic;
+typedef FinvBound<invariant X extends core::num*> = (X*) →* X*;
+typedef FcovCyclicBound<X extends self::A<X*>* = self::A<dynamic>*> = () →* X*;
+typedef FconCyclicBound<contravariant X extends self::A<X*>* = self::A<Null>*> = (X*) →* dynamic;
+typedef FinvCyclicBound<invariant X extends self::A<X*>* = self::A<dynamic>*> = (X*) →* X*;
+typedef FcovCyclicCoBound<X extends (X*) →* dynamic = (Null) →* dynamic> = () →* X*;
+typedef FconCyclicCoBound<contravariant X extends (X*) →* dynamic = (dynamic) →* dynamic> = (X*) →* dynamic;
+typedef FinvCyclicCoBound<invariant X extends (X*) →* dynamic = (dynamic) →* dynamic> = (X*) →* X*;
+class A<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method toF<X extends core::Object* = dynamic>(self::toF::X* x) → <Y extends self::toF::X* = dynamic>() →* void
+  return null;
+static method testTopLevel() → void {
+  () →* dynamic source1;
+  <Y extends () →* dynamic = dynamic>() →* void fsource1 = self::toF<() →* dynamic>(source1);
+  <Y extends () →* dynamic = dynamic>() →* void target1 = fsource1;
+  (dynamic) →* dynamic source2;
+  <Y extends (dynamic) →* dynamic = dynamic>() →* void fsource2 = self::toF<(dynamic) →* dynamic>(source2);
+  <Y extends (dynamic) →* dynamic = dynamic>() →* void target2 = fsource2;
+  (dynamic) →* dynamic source3;
+  <Y extends (dynamic) →* dynamic = dynamic>() →* void fsource3 = self::toF<(dynamic) →* dynamic>(source3);
+  <Y extends (dynamic) →* dynamic = dynamic>() →* void target3 = fsource3;
+  () →* core::num* source4;
+  <Y extends () →* core::num* = dynamic>() →* void fsource4 = self::toF<() →* core::num*>(source4);
+  <Y extends () →* core::num* = dynamic>() →* void target4 = fsource4;
+  (core::num*) →* dynamic source5;
+  <Y extends (core::num*) →* dynamic = dynamic>() →* void fsource5 = self::toF<(core::num*) →* dynamic>(source5);
+  <Y extends (core::num*) →* dynamic = dynamic>() →* void target5 = fsource5;
+  (core::num*) →* core::num* source6;
+  <Y extends (core::num*) →* core::num* = dynamic>() →* void fsource6 = self::toF<(core::num*) →* core::num*>(source6);
+  <Y extends (core::num*) →* core::num* = dynamic>() →* void target6 = fsource6;
+  () →* self::A<dynamic>* source7;
+  <Y extends () →* self::A<dynamic>* = dynamic>() →* void fsource7 = self::toF<() →* self::A<dynamic>*>(source7);
+  <Y extends () →* self::A<dynamic>* = dynamic>() →* void target7 = fsource7;
+  (self::A<Null>*) →* dynamic source8;
+  <Y extends (self::A<Null>*) →* dynamic = dynamic>() →* void fsource8 = self::toF<(self::A<Null>*) →* dynamic>(source8);
+  <Y extends (self::A<Null>*) →* dynamic = dynamic>() →* void target8 = fsource8;
+  (self::A<dynamic>*) →* self::A<dynamic>* source9;
+  () →* (Null) →* dynamic source10;
+  <Y extends () →* (Null) →* dynamic = dynamic>() →* void fsource10 = self::toF<() →* (Null) →* dynamic>(source10);
+  <Y extends () →* (Null) →* dynamic = dynamic>() →* void target10 = fsource10;
+  ((dynamic) →* dynamic) →* dynamic source11;
+  <Y extends ((dynamic) →* dynamic) →* dynamic = dynamic>() →* void fsource11 = self::toF<((dynamic) →* dynamic) →* dynamic>(source11);
+  <Y extends ((dynamic) →* dynamic) →* dynamic = dynamic>() →* void target11 = fsource11;
+  ((dynamic) →* dynamic) →* (dynamic) →* dynamic source12;
+  <Y extends ((dynamic) →* dynamic) →* (dynamic) →* dynamic = dynamic>() →* void fsource12 = self::toF<((dynamic) →* dynamic) →* (dynamic) →* dynamic>(source12);
+  <Y extends ((dynamic) →* dynamic) →* (dynamic) →* dynamic = dynamic>() →* void target12 = fsource12;
+}
+static method testNested() → void {
+  self::B<() →* dynamic>* source1;
+  <Y extends self::B<() →* dynamic>* = dynamic>() →* void fsource1 = self::toF<self::B<() →* dynamic>*>(source1);
+  <Y extends self::B<() →* dynamic>* = dynamic>() →* void target1 = fsource1;
+  self::B<(dynamic) →* dynamic>* source2;
+  <Y extends self::B<(dynamic) →* dynamic>* = dynamic>() →* void fsource2 = self::toF<self::B<(dynamic) →* dynamic>*>(source2);
+  <Y extends self::B<(dynamic) →* dynamic>* = dynamic>() →* void target2 = fsource2;
+  self::B<(dynamic) →* dynamic>* source3;
+  <Y extends self::B<(dynamic) →* dynamic>* = dynamic>() →* void fsource3 = self::toF<self::B<(dynamic) →* dynamic>*>(source3);
+  <Y extends self::B<(dynamic) →* dynamic>* = dynamic>() →* void target3 = fsource3;
+  self::B<() →* core::num*>* source4;
+  <Y extends self::B<() →* core::num*>* = dynamic>() →* void fsource4 = self::toF<self::B<() →* core::num*>*>(source4);
+  <Y extends self::B<() →* core::num*>* = dynamic>() →* void target4 = fsource4;
+  self::B<(core::num*) →* dynamic>* source5;
+  <Y extends self::B<(core::num*) →* dynamic>* = dynamic>() →* void fsource5 = self::toF<self::B<(core::num*) →* dynamic>*>(source5);
+  <Y extends self::B<(core::num*) →* dynamic>* = dynamic>() →* void target5 = fsource5;
+  self::B<(core::num*) →* core::num*>* source6;
+  <Y extends self::B<(core::num*) →* core::num*>* = dynamic>() →* void fsource6 = self::toF<self::B<(core::num*) →* core::num*>*>(source6);
+  <Y extends self::B<(core::num*) →* core::num*>* = dynamic>() →* void target6 = fsource6;
+  self::B<() →* self::A<dynamic>*>* source7;
+  <Y extends self::B<() →* self::A<dynamic>*>* = dynamic>() →* void fsource7 = self::toF<self::B<() →* self::A<dynamic>*>*>(source7);
+  <Y extends self::B<() →* self::A<dynamic>*>* = dynamic>() →* void target7 = fsource7;
+  self::B<(self::A<Null>*) →* dynamic>* source8;
+  <Y extends self::B<(self::A<Null>*) →* dynamic>* = dynamic>() →* void fsource8 = self::toF<self::B<(self::A<Null>*) →* dynamic>*>(source8);
+  <Y extends self::B<(self::A<Null>*) →* dynamic>* = dynamic>() →* void target8 = fsource8;
+  self::B<(self::A<dynamic>*) →* self::A<dynamic>*>* source9;
+  self::B<() →* (Null) →* dynamic>* source10;
+  <Y extends self::B<() →* (Null) →* dynamic>* = dynamic>() →* void fsource10 = self::toF<self::B<() →* (Null) →* dynamic>*>(source10);
+  <Y extends self::B<() →* (Null) →* dynamic>* = dynamic>() →* void target10 = fsource10;
+  self::B<((dynamic) →* dynamic) →* dynamic>* source11;
+  <Y extends self::B<((dynamic) →* dynamic) →* dynamic>* = dynamic>() →* void fsource11 = self::toF<self::B<((dynamic) →* dynamic) →* dynamic>*>(source11);
+  <Y extends self::B<((dynamic) →* dynamic) →* dynamic>* = dynamic>() →* void target11 = fsource11;
+  self::B<((dynamic) →* dynamic) →* (dynamic) →* dynamic>* source12;
+  <Y extends self::B<((dynamic) →* dynamic) →* (dynamic) →* dynamic>* = dynamic>() →* void fsource12 = self::toF<self::B<((dynamic) →* dynamic) →* (dynamic) →* dynamic>*>(source12);
+  <Y extends self::B<((dynamic) →* dynamic) →* (dynamic) →* dynamic>* = dynamic>() →* void target12 = fsource12;
+}
+static method main() → dynamic {
+  self::testTopLevel();
+  self::testNested();
+}
diff --git a/pkg/front_end/testcases/general/type_literal_as_metadata.dart.weak.modular.expect b/pkg/front_end/testcases/general/type_literal_as_metadata.dart.weak.modular.expect
new file mode 100644
index 0000000..6039ee4
--- /dev/null
+++ b/pkg/front_end/testcases/general/type_literal_as_metadata.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/type_literal_as_metadata.dart:9:2: Error: This can't be used as an annotation; an annotation should be a reference to a compile-time constant variable, or a call to a constant constructor.
+// @A
+//  ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+@invalid-expression "pkg/front_end/testcases/general/type_literal_as_metadata.dart:9:2: Error: This can't be used as an annotation; an annotation should be a reference to a compile-time constant variable, or a call to a constant constructor.
+@A
+ ^"
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/type_of_null.dart.weak.modular.expect b/pkg/front_end/testcases/general/type_of_null.dart.weak.modular.expect
new file mode 100644
index 0000000..4f0b860
--- /dev/null
+++ b/pkg/front_end/testcases/general/type_of_null.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method map<T extends core::Object* = dynamic>(() →* self::map::T* f1, () →* self::map::T* f2) → self::map::T* {}
+static method id<T extends core::Object* = dynamic>(self::id::T* t) → dynamic
+  return t;
+static method foo() → Null
+  return null;
+static method main() → dynamic {
+  self::map<Null>(() → Null {}, () → Null => throw "hello");
+  self::map<Null>(() → Null => throw "hello", () → Null {});
+  () →* Null f = () → Null {};
+  self::map<Null>(#C1, () → Null => throw "hello");
+  self::map<Null>(() → Null => throw "hello", #C1);
+  self::map<Null>(() → Null {
+    return null;
+  }, () → Null => throw "hello");
+  self::map<Null>(() → Null => throw "hello", () → Null {
+    return null;
+  });
+  self::id<() →* Null>(() → Null {});
+}
+
+constants  {
+  #C1 = static-tearoff self::foo
+}
diff --git a/pkg/front_end/testcases/general/type_parameter_type_named_int.dart.weak.modular.expect b/pkg/front_end/testcases/general/type_parameter_type_named_int.dart.weak.modular.expect
new file mode 100644
index 0000000..ea169b3
--- /dev/null
+++ b/pkg/front_end/testcases/general/type_parameter_type_named_int.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/type_parameter_type_named_int.dart:13:12: Error: A value of type 'List<int/*1*/>' can't be assigned to a variable of type 'List<int/*2*/>'.
+//  - 'List' is from 'dart:core'.
+//  - 'int/*1*/' is from 'pkg/front_end/testcases/general/type_parameter_type_named_int.dart'.
+//  - 'int/*2*/' is from 'dart:core'.
+//     list = value;
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Foo<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Foo<self::Foo::T*>*
+    : super core::Object::•()
+    ;
+  abstract get list() → core::List<self::Foo::T*>*;
+  abstract method setList<T extends core::Object* = dynamic>(core::List<self::Foo::setList::T*>* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar extends core::Object implements self::Foo<core::int*> {
+  field core::List<core::int*>* list = null;
+  synthetic constructor •() → self::Bar*
+    : super core::Object::•()
+    ;
+  method setList<int extends core::Object* = dynamic>(core::List<self::Bar::setList::int*>* value) → void {
+    this.{self::Bar::list} = invalid-expression "pkg/front_end/testcases/general/type_parameter_type_named_int.dart:13:12: Error: A value of type 'List<int/*1*/>' can't be assigned to a variable of type 'List<int/*2*/>'.
+ - 'List' is from 'dart:core'.
+ - 'int/*1*/' is from 'pkg/front_end/testcases/general/type_parameter_type_named_int.dart'.
+ - 'int/*2*/' is from 'dart:core'.
+    list = value;
+           ^" in value as{TypeError} core::List<core::int*>*;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart.weak.modular.expect b/pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart.weak.modular.expect
new file mode 100644
index 0000000..cb0d959
--- /dev/null
+++ b/pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart.weak.modular.expect
@@ -0,0 +1,206 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:6:10: Error: Type variables can't be used in static members.
+//   static U foo1() { return null; }
+//          ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:7:15: Error: Type variables can't be used in static members.
+//   static List<U> foo1Prime() { return null; }
+//               ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:8:20: Error: Type variables can't be used in static members.
+//   static void foo2(U x) { return null; }
+//                    ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:9:30: Error: Type variables can't be used in static members.
+//   static void foo2Prime(List<U> x) { return null; }
+//                              ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:20:10: Error: Type variables can't be used in static members.
+//   static U Function() foo8() { return null; }
+//          ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:21:15: Error: Type variables can't be used in static members.
+//   static List<U> Function() foo8Prime() { return null; }
+//               ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:22:24: Error: Type variables can't be used in static members.
+//   static void Function(U) foo9() { return null; }
+//                        ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:23:29: Error: Type variables can't be used in static members.
+//   static void Function(List<U>) foo9Prime() { return null; }
+//                             ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:24:21: Error: Type variables can't be used in static members.
+//   static void foo10(U Function()) { return null; }
+//                     ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:25:31: Error: Type variables can't be used in static members.
+//   static void foo10Prime(List<U> Function()) { return null; }
+//                               ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:28:35: Error: Type variables can't be used in static members.
+//   static void foo12(void Function(U) b) { return null; }
+//                                   ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:29:45: Error: Type variables can't be used in static members.
+//   static void foo12Prime(void Function(List<U>) b) { return null; }
+//                                             ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:31:35: Error: Type variables can't be used in static members.
+//   static void foo13(void Function(U b)) { return null; }
+//                                   ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:33:45: Error: Type variables can't be used in static members.
+//   static void foo13Prime(void Function(List<U> b)) { return null; }
+//                                             ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:34:10: Error: Type variables can't be used in static members.
+//   static U foo14 = null;
+//          ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:35:15: Error: Type variables can't be used in static members.
+//   static List<U> foo14Prime = null;
+//               ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:36:10: Error: Type variables can't be used in static members.
+//   static U Function(U) foo15 = null;
+//          ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:36:21: Error: Type variables can't be used in static members.
+//   static U Function(U) foo15 = null;
+//                     ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:37:15: Error: Type variables can't be used in static members.
+//   static List<U> Function(List<U>) foo15Prime = null;
+//               ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:37:32: Error: Type variables can't be used in static members.
+//   static List<U> Function(List<U>) foo15Prime = null;
+//                                ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:11:5: Error: Type variables can't be used in static members.
+//     U foo4;
+//     ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:12:10: Error: Type variables can't be used in static members.
+//     List<U> foo4Prime;
+//          ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:13:15: Error: Type variables can't be used in static members.
+//     void foo5(U y) => print(y);
+//               ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:14:25: Error: Type variables can't be used in static members.
+//     void foo5Prime(List<U> y) => print(y);
+//                         ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:15:5: Error: Type variables can't be used in static members.
+//     U foo6() => null;
+//     ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:16:10: Error: Type variables can't be used in static members.
+//     List<U> foo6Prime() => null;
+//          ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:17:20: Error: Type variables can't be used in static members.
+//     void Function (U y) foo7 = (U y) => y;
+//                    ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:17:33: Error: Type variables can't be used in static members.
+//     void Function (U y) foo7 = (U y) => y;
+//                                 ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:18:25: Error: Type variables can't be used in static members.
+//     void Function (List<U> y) foo7Prime = (List<U> y) => y;
+//                         ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_class.dart:18:49: Error: Type variables can't be used in static members.
+//     void Function (List<U> y) foo7Prime = (List<U> y) => y;
+//                                                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo<U extends core::Object* = dynamic> extends core::Object {
+  static field invalid-type foo14 = null;
+  static field core::List<invalid-type>* foo14Prime = null;
+  static field (invalid-type) →* invalid-type foo15 = null;
+  static field (core::List<invalid-type>*) →* core::List<invalid-type>* foo15Prime = null;
+  synthetic constructor •() → self::Foo<self::Foo::U*>*
+    : super core::Object::•()
+    ;
+  static method foo1() → invalid-type {
+    return null;
+  }
+  static method foo1Prime() → core::List<invalid-type>* {
+    return null;
+  }
+  static method foo2(invalid-type x) → void {
+    return null;
+  }
+  static method foo2Prime(core::List<invalid-type>* x) → void {
+    return null;
+  }
+  static method foo3() → void {
+    invalid-type foo4;
+    core::List<invalid-type>* foo4Prime;
+    function foo5(invalid-type y) → void
+      return core::print(y);
+    function foo5Prime(core::List<invalid-type>* y) → void
+      return core::print(y);
+    function foo6() → invalid-type
+      return null;
+    function foo6Prime() → core::List<invalid-type>*
+      return null;
+    (invalid-type) →* void foo7 = (invalid-type y) → invalid-type => y;
+    (core::List<invalid-type>*) →* void foo7Prime = (core::List<invalid-type>* y) → core::List<invalid-type>* => y;
+  }
+  static method foo8() → () →* invalid-type {
+    return null;
+  }
+  static method foo8Prime() → () →* core::List<invalid-type>* {
+    return null;
+  }
+  static method foo9() → (invalid-type) →* void {
+    return null;
+  }
+  static method foo9Prime() → (core::List<invalid-type>*) →* void {
+    return null;
+  }
+  static method foo10(() →* invalid-type Function) → void {
+    return null;
+  }
+  static method foo10Prime(() →* core::List<invalid-type>* Function) → void {
+    return null;
+  }
+  static method foo11((dynamic) →* void Function) → void {
+    return null;
+  }
+  static method foo12((invalid-type) →* void b) → void {
+    return null;
+  }
+  static method foo12Prime((core::List<invalid-type>*) →* void b) → void {
+    return null;
+  }
+  static method foo13((invalid-type) →* void Function) → void {
+    return null;
+  }
+  static method foo13Prime((core::List<invalid-type>*) →* void Function) → void {
+    return null;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart.weak.modular.expect b/pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart.weak.modular.expect
new file mode 100644
index 0000000..d4e95b2
--- /dev/null
+++ b/pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart.weak.modular.expect
@@ -0,0 +1,213 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:6:10: Error: Type variables can't be used in static members.
+//   static U foo1() { return null; }
+//          ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:7:15: Error: Type variables can't be used in static members.
+//   static List<U> foo1Prime() { return null; }
+//               ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:8:20: Error: Type variables can't be used in static members.
+//   static void foo2(U x) { return null; }
+//                    ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:9:30: Error: Type variables can't be used in static members.
+//   static void foo2Prime(List<U> x) { return null; }
+//                              ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:20:10: Error: Type variables can't be used in static members.
+//   static U Function() foo8() { return null; }
+//          ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:21:15: Error: Type variables can't be used in static members.
+//   static List<U> Function() foo8Prime() { return null; }
+//               ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:22:24: Error: Type variables can't be used in static members.
+//   static void Function(U) foo9() { return null; }
+//                        ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:23:29: Error: Type variables can't be used in static members.
+//   static void Function(List<U>) foo9Prime() { return null; }
+//                             ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:24:21: Error: Type variables can't be used in static members.
+//   static void foo10(U Function()) { return null; }
+//                     ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:25:31: Error: Type variables can't be used in static members.
+//   static void foo10Prime(List<U> Function()) { return null; }
+//                               ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:28:35: Error: Type variables can't be used in static members.
+//   static void foo12(void Function(U) b) { return null; }
+//                                   ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:29:45: Error: Type variables can't be used in static members.
+//   static void foo12Prime(void Function(List<U>) b) { return null; }
+//                                             ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:31:35: Error: Type variables can't be used in static members.
+//   static void foo13(void Function(U b)) { return null; }
+//                                   ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:33:45: Error: Type variables can't be used in static members.
+//   static void foo13Prime(void Function(List<U> b)) { return null; }
+//                                             ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:34:10: Error: Type variables can't be used in static members.
+//   static U foo14 = null;
+//          ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:35:15: Error: Type variables can't be used in static members.
+//   static List<U> foo14Prime = null;
+//               ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:36:10: Error: Type variables can't be used in static members.
+//   static U Function(U) foo15 = null;
+//          ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:36:21: Error: Type variables can't be used in static members.
+//   static U Function(U) foo15 = null;
+//                     ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:37:15: Error: Type variables can't be used in static members.
+//   static List<U> Function(List<U>) foo15Prime = null;
+//               ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:37:32: Error: Type variables can't be used in static members.
+//   static List<U> Function(List<U>) foo15Prime = null;
+//                                ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:11:5: Error: Type variables can't be used in static members.
+//     U foo4;
+//     ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:12:10: Error: Type variables can't be used in static members.
+//     List<U> foo4Prime;
+//          ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:13:15: Error: Type variables can't be used in static members.
+//     void foo5(U y) => print(y);
+//               ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:14:25: Error: Type variables can't be used in static members.
+//     void foo5Prime(List<U> y) => print(y);
+//                         ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:15:5: Error: Type variables can't be used in static members.
+//     U foo6() => null;
+//     ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:16:10: Error: Type variables can't be used in static members.
+//     List<U> foo6Prime() => null;
+//          ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:17:20: Error: Type variables can't be used in static members.
+//     void Function (U y) foo7 = (U y) => y;
+//                    ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:17:33: Error: Type variables can't be used in static members.
+//     void Function (U y) foo7 = (U y) => y;
+//                                 ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:18:25: Error: Type variables can't be used in static members.
+//     void Function (List<U> y) foo7Prime = (List<U> y) => y;
+//                         ^
+//
+// pkg/front_end/testcases/general/type_parameter_usage_in_static_method_in_extension.dart:18:49: Error: Type variables can't be used in static members.
+//     void Function (List<U> y) foo7Prime = (List<U> y) => y;
+//                                                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+extension Foo<U extends core::Object* = dynamic> on core::List<dynamic>* {
+  static method foo1 = self::Foo|foo1;
+  static method foo1Prime = self::Foo|foo1Prime;
+  static method foo2 = self::Foo|foo2;
+  static method foo2Prime = self::Foo|foo2Prime;
+  static method foo3 = self::Foo|foo3;
+  static method foo8 = self::Foo|foo8;
+  static method foo8Prime = self::Foo|foo8Prime;
+  static method foo9 = self::Foo|foo9;
+  static method foo9Prime = self::Foo|foo9Prime;
+  static method foo10 = self::Foo|foo10;
+  static method foo10Prime = self::Foo|foo10Prime;
+  static method foo11 = self::Foo|foo11;
+  static method foo12 = self::Foo|foo12;
+  static method foo12Prime = self::Foo|foo12Prime;
+  static method foo13 = self::Foo|foo13;
+  static method foo13Prime = self::Foo|foo13Prime;
+  static field foo14 = self::Foo|foo14;
+  static field foo14Prime = self::Foo|foo14Prime;
+  static field foo15 = self::Foo|foo15;
+  static field foo15Prime = self::Foo|foo15Prime;
+}
+static field invalid-type Foo|foo14 = null;
+static field core::List<invalid-type>* Foo|foo14Prime = null;
+static field (invalid-type) →* invalid-type Foo|foo15 = null;
+static field (core::List<invalid-type>*) →* core::List<invalid-type>* Foo|foo15Prime = null;
+static method Foo|foo1() → invalid-type {
+  return null;
+}
+static method Foo|foo1Prime() → core::List<invalid-type>* {
+  return null;
+}
+static method Foo|foo2(invalid-type x) → void {
+  return null;
+}
+static method Foo|foo2Prime(core::List<invalid-type>* x) → void {
+  return null;
+}
+static method Foo|foo3() → void {
+  invalid-type foo4;
+  core::List<invalid-type>* foo4Prime;
+  function foo5(invalid-type y) → void
+    return core::print(y);
+  function foo5Prime(core::List<invalid-type>* y) → void
+    return core::print(y);
+  function foo6() → invalid-type
+    return null;
+  function foo6Prime() → core::List<invalid-type>*
+    return null;
+  (invalid-type) →* void foo7 = (invalid-type y) → invalid-type => y;
+  (core::List<invalid-type>*) →* void foo7Prime = (core::List<invalid-type>* y) → core::List<invalid-type>* => y;
+}
+static method Foo|foo8() → () →* invalid-type {
+  return null;
+}
+static method Foo|foo8Prime() → () →* core::List<invalid-type>* {
+  return null;
+}
+static method Foo|foo9() → (invalid-type) →* void {
+  return null;
+}
+static method Foo|foo9Prime() → (core::List<invalid-type>*) →* void {
+  return null;
+}
+static method Foo|foo10(() →* invalid-type Function) → void {
+  return null;
+}
+static method Foo|foo10Prime(() →* core::List<invalid-type>* Function) → void {
+  return null;
+}
+static method Foo|foo11((dynamic) →* void Function) → void {
+  return null;
+}
+static method Foo|foo12((invalid-type) →* void b) → void {
+  return null;
+}
+static method Foo|foo12Prime((core::List<invalid-type>*) →* void b) → void {
+  return null;
+}
+static method Foo|foo13((invalid-type) →* void Function) → void {
+  return null;
+}
+static method Foo|foo13Prime((core::List<invalid-type>*) →* void Function) → void {
+  return null;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/type_parameters_on_dynamic.dart.weak.modular.expect b/pkg/front_end/testcases/general/type_parameters_on_dynamic.dart.weak.modular.expect
new file mode 100644
index 0000000..bdb4a9f
--- /dev/null
+++ b/pkg/front_end/testcases/general/type_parameters_on_dynamic.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/type_parameters_on_dynamic.dart:2:1: Error: Expected 0 type arguments.
+// dynamic<int> f() {}
+// ^
+//
+import self as self;
+
+static method f() → invalid-type {}
+static method main() → dynamic {
+  self::f();
+}
diff --git a/pkg/front_end/testcases/general/type_parameters_on_void.dart.weak.modular.expect b/pkg/front_end/testcases/general/type_parameters_on_void.dart.weak.modular.expect
new file mode 100644
index 0000000..6e6a65f
--- /dev/null
+++ b/pkg/front_end/testcases/general/type_parameters_on_void.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/type_parameters_on_void.dart:1:5: Error: Type 'void' can't have type arguments.
+// Try removing the type arguments.
+// void<int> f() {}
+//     ^
+//
+import self as self;
+
+static method f() → void {}
+static method main() → dynamic {
+  self::f();
+}
diff --git a/pkg/front_end/testcases/general/type_variable_annotations.dart.weak.modular.expect b/pkg/front_end/testcases/general/type_variable_annotations.dart.weak.modular.expect
new file mode 100644
index 0000000..21c0f72
--- /dev/null
+++ b/pkg/front_end/testcases/general/type_variable_annotations.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef F<@#C1 contravariant T extends core::Object? = dynamic> = (T%) → void;
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class Class<@#C1 T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  method method<@#C1 T extends core::Object? = dynamic>() → void {
+    function local<@#C1 T extends core::Object? = dynamic>() → void {}
+  }
+}
+extension Extension<@#C1 T extends core::Object? = dynamic> on T% {
+  method method = self::Extension|method;
+  tearoff method = self::Extension|get#method;
+}
+static method method<@#C1 T extends core::Object? = dynamic>() → void {}
+static method Extension|method<#T extends core::Object? = dynamic, @#C1 T extends core::Object? = dynamic>(lowered final self::Extension|method::#T% #this) → void {}
+static method Extension|get#method<#T extends core::Object? = dynamic>(lowered final self::Extension|get#method::#T% #this) → <T extends core::Object? = dynamic>() → void
+  return <T extends core::Object? = dynamic>() → void => self::Extension|method<self::Extension|get#method::#T%, T%>(#this);
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::A {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///type_variable_annotations.dart:
+- A. (from org-dartlang-testcase:///type_variable_annotations.dart:6:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/type_variable_as_super.dart.weak.modular.expect b/pkg/front_end/testcases/general/type_variable_as_super.dart.weak.modular.expect
new file mode 100644
index 0000000..aac4117
--- /dev/null
+++ b/pkg/front_end/testcases/general/type_variable_as_super.dart.weak.modular.expect
@@ -0,0 +1,77 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/type_variable_as_super.dart:5:16: Error: The type variable 'T' can't be used as supertype.
+// abstract class A<T> extends T {}
+//                ^
+//
+// pkg/front_end/testcases/general/type_variable_as_super.dart:7:16: Error: The type variable 'T' can't be used as supertype.
+// abstract class B<T> extends T {
+//                ^
+//
+// pkg/front_end/testcases/general/type_variable_as_super.dart:11:7: Error: The type variable 'T' can't be used as supertype.
+// class C<T> extends T {}
+//       ^
+//
+// pkg/front_end/testcases/general/type_variable_as_super.dart:14:7: Error: The class 'A' is abstract and can't be instantiated.
+//   new A();
+//       ^
+//
+// pkg/front_end/testcases/general/type_variable_as_super.dart:15:7: Error: The class 'B' is abstract and can't be instantiated.
+//   new B();
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B<T extends core::Object* = dynamic> extends core::Object {
+  constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  throw new core::AbstractClassInstantiationError::•("A");
+  throw new core::AbstractClassInstantiationError::•("B");
+  new self::C::•<dynamic>();
+}
diff --git a/pkg/front_end/testcases/general/type_variable_bound_access.dart.weak.modular.expect b/pkg/front_end/testcases/general/type_variable_bound_access.dart.weak.modular.expect
new file mode 100644
index 0000000..c281ff0
--- /dev/null
+++ b/pkg/front_end/testcases/general/type_variable_bound_access.dart.weak.modular.expect
@@ -0,0 +1,88 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/type_variable_bound_access.dart:22:36: Error: The getter 'length' isn't defined for the class 'num'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'length'.
+//   num method2() => field1 + field2.length;
+//                                    ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class DynamicClass<T extends dynamic, S extends self::DynamicClass::T* = dynamic> extends core::Object {
+  covariant-by-class field self::DynamicClass::T* field1;
+  covariant-by-class field self::DynamicClass::T* field2;
+  constructor •(self::DynamicClass::T* field1, self::DynamicClass::T* field2) → self::DynamicClass<self::DynamicClass::T*, self::DynamicClass::S*>*
+    : self::DynamicClass::field1 = field1, self::DynamicClass::field2 = field2, super core::Object::•()
+    ;
+  method method() → dynamic
+    return this.{self::DynamicClass::field1}{self::DynamicClass::T*}{dynamic}.*(this.{self::DynamicClass::field2}{self::DynamicClass::T*});
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class NumClass<T extends core::num*, S extends self::NumClass::T* = core::num*> extends core::Object {
+  covariant-by-class field self::NumClass::T* field1;
+  covariant-by-class field self::NumClass::S* field2;
+  constructor •(self::NumClass::T* field1, self::NumClass::S* field2) → self::NumClass<self::NumClass::T*, self::NumClass::S*>*
+    : self::NumClass::field1 = field1, self::NumClass::field2 = field2, super core::Object::•()
+    ;
+  method method1() → core::num*
+    return this.{self::NumClass::field1}{self::NumClass::T*}.{core::num::*}(this.{self::NumClass::field2}{self::NumClass::S*}){(core::num*) →* core::num*};
+  method method2() → core::num*
+    return this.{self::NumClass::field1}{self::NumClass::T*}.{core::num::+}(invalid-expression "pkg/front_end/testcases/general/type_variable_bound_access.dart:22:36: Error: The getter 'length' isn't defined for the class 'num'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'length'.
+  num method2() => field1 + field2.length;
+                                   ^^^^^^" in this.{self::NumClass::field2}{self::NumClass::S*}{<unresolved>}.length as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class<X5 extends self::Class::X4* = core::int*, X4 extends self::Class::X3* = core::int*, X3 extends self::Class::X2* = core::int*, X2 extends self::Class::X1* = core::int*, X1 extends self::Class::X0* = core::int*, X0 extends core::int*> extends core::Object {
+  covariant-by-class field self::Class::X0* field0 = null;
+  covariant-by-class field self::Class::X1* field1 = null;
+  covariant-by-class field self::Class::X2* field2 = null;
+  covariant-by-class field self::Class::X3* field3 = null;
+  covariant-by-class field self::Class::X4* field4 = null;
+  covariant-by-class field self::Class::X5* field5 = null;
+  synthetic constructor •() → self::Class<self::Class::X5*, self::Class::X4*, self::Class::X3*, self::Class::X2*, self::Class::X1*, self::Class::X0*>*
+    : super core::Object::•()
+    ;
+  method method() → dynamic {
+    this.{self::Class::field0}{self::Class::X0*}.{core::int::isEven}{core::bool*};
+    this.{self::Class::field1}{self::Class::X1*}.{core::int::isEven}{core::bool*};
+    this.{self::Class::field2}{self::Class::X2*}.{core::int::isEven}{core::bool*};
+    this.{self::Class::field3}{self::Class::X3*}.{core::int::isEven}{core::bool*};
+    this.{self::Class::field4}{self::Class::X4*}.{core::int::isEven}{core::bool*};
+    this.{self::Class::field5}{self::Class::X5*}.{core::int::isEven}{core::bool*};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::DynamicClass::•<core::num*, core::int*>(0.5, 2).{self::DynamicClass::method}(){() →* dynamic};
+  new self::NumClass::•<core::num*, core::double*>(2, 0.5).{self::NumClass::method1}(){() →* core::num*};
+}
diff --git a/pkg/front_end/testcases/general/type_variable_in_static_context.dart.weak.modular.expect b/pkg/front_end/testcases/general/type_variable_in_static_context.dart.weak.modular.expect
new file mode 100644
index 0000000..31bd8fe
--- /dev/null
+++ b/pkg/front_end/testcases/general/type_variable_in_static_context.dart.weak.modular.expect
@@ -0,0 +1,630 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:105:3: Error: Extensions can't declare constructors.
+// Try removing the constructor declaration.
+//   Extension(T t);
+//   ^^^^^^^^^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:107:3: Error: Extensions can't declare constructors.
+// Try removing the constructor declaration.
+//   factory Extension.fact(T t) => null;
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:113:5: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   T field1;
+//     ^^^^^^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:130:3: Error: Mixins can't declare constructors.
+//   Mixin(T t);
+//   ^^^^^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:132:3: Error: Mixins can't declare constructors.
+//   factory Mixin.fact(T t) => null;
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:107:11: Error: Expected 0 type arguments.
+//   factory Extension.fact(T t) => null;
+//           ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:13:31: Error: Type variables can't be used in static members.
+//   static T? method0<S extends T>(T arg) {
+//                               ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:20:44: Error: Type variables can't be used in static members.
+//   static Class<T>? method1<S extends Class<T>>(Class<T> arg) {
+//                                            ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:29:57: Error: Type variables can't be used in static members.
+//   static Class<Class<T>>? method2<S extends Class<Class<T>>>(Class<Class<T>> arg) {
+//                                                         ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:38:36: Error: Type variables can't be used in static members.
+//   static A<T>? method3<S extends A<T>>(A<T> arg) {
+//                                    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:47:41: Error: Type variables can't be used in static members.
+//   static A<A<T>>? method4<S extends A<A<T>>>(A<A<T>> arg) {
+//                                         ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:56:36: Error: Type variables can't be used in static members.
+//   static B<T>? method5<S extends B<T>>(B<T> arg) {
+//                                    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:65:41: Error: Type variables can't be used in static members.
+//   static A<B<T>>? method6<S extends A<B<T>>>(A<B<T>> arg) {
+//                                         ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:73:34: Error: Type variables can't be used in static members.
+//   @Class<void Function<S extends T>()>()
+//                                  ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:74:34: Error: Type variables can't be used in static members.
+//   static void Function<S extends T>()? method7<U extends void Function<S extends T>()>(void Function<S extends T>() arg) {
+//                                  ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:74:82: Error: Type variables can't be used in static members.
+//   static void Function<S extends T>()? method7<U extends void Function<S extends T>()>(void Function<S extends T>() arg) {
+//                                                                                  ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:74:112: Error: Type variables can't be used in static members.
+//   static void Function<S extends T>()? method7<U extends void Function<S extends T>()>(void Function<S extends T>() arg) {
+//                                                                                                                ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:116:36: Error: Type variables can't be used in static members.
+//   static T? staticMethod<S extends T>(T arg) {
+//                                    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:138:36: Error: Type variables can't be used in static members.
+//   static T? staticMethod<S extends T>(T arg) {
+//                                    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:13:34: Error: Type variables can't be used in static members.
+//   static T? method0<S extends T>(T arg) {
+//                                  ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:13:10: Error: Type variables can't be used in static members.
+//   static T? method0<S extends T>(T arg) {
+//          ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:20:54: Error: Type variables can't be used in static members.
+//   static Class<T>? method1<S extends Class<T>>(Class<T> arg) {
+//                                                      ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:20:16: Error: Type variables can't be used in static members.
+//   static Class<T>? method1<S extends Class<T>>(Class<T> arg) {
+//                ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:29:74: Error: Type variables can't be used in static members.
+//   static Class<Class<T>>? method2<S extends Class<Class<T>>>(Class<Class<T>> arg) {
+//                                                                          ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:29:22: Error: Type variables can't be used in static members.
+//   static Class<Class<T>>? method2<S extends Class<Class<T>>>(Class<Class<T>> arg) {
+//                      ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:38:42: Error: Type variables can't be used in static members.
+//   static A<T>? method3<S extends A<T>>(A<T> arg) {
+//                                          ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:38:12: Error: Type variables can't be used in static members.
+//   static A<T>? method3<S extends A<T>>(A<T> arg) {
+//            ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:47:50: Error: Type variables can't be used in static members.
+//   static A<A<T>>? method4<S extends A<A<T>>>(A<A<T>> arg) {
+//                                                  ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:47:14: Error: Type variables can't be used in static members.
+//   static A<A<T>>? method4<S extends A<A<T>>>(A<A<T>> arg) {
+//              ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:56:42: Error: Type variables can't be used in static members.
+//   static B<T>? method5<S extends B<T>>(B<T> arg) {
+//                                          ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:56:12: Error: Type variables can't be used in static members.
+//   static B<T>? method5<S extends B<T>>(B<T> arg) {
+//            ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:65:50: Error: Type variables can't be used in static members.
+//   static A<B<T>>? method6<S extends A<B<T>>>(A<B<T>> arg) {
+//                                                  ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:65:14: Error: Type variables can't be used in static members.
+//   static A<B<T>>? method6<S extends A<B<T>>>(A<B<T>> arg) {
+//              ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:80:10: Error: Type variables can't be used in static members.
+//   static T field0;
+//          ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:83:16: Error: Type variables can't be used in static members.
+//   static Class<T>? field1;
+//                ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:110:10: Error: Type variables can't be used in static members.
+//   static T field0;
+//          ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:116:39: Error: Type variables can't be used in static members.
+//   static T? staticMethod<S extends T>(T arg) {
+//                                       ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:116:10: Error: Type variables can't be used in static members.
+//   static T? staticMethod<S extends T>(T arg) {
+//          ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:135:10: Error: Type variables can't be used in static members.
+//   static T field0;
+//          ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:138:39: Error: Type variables can't be used in static members.
+//   static T? staticMethod<S extends T>(T arg) {
+//                                       ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:138:10: Error: Type variables can't be used in static members.
+//   static T? staticMethod<S extends T>(T arg) {
+//          ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:92:24: Error: Type variables can't be used in static members.
+//   static var field4 = (T t) => T;
+//                        ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:92:32: Error: Type variables can't be used in static members.
+//   static var field4 = (T t) => T;
+//                                ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:12:4: Error: Couldn't find constructor 'T'.
+//   @T()
+//    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:19:10: Error: Type variables can't be used in static members.
+//   @Class<T>()
+//          ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:28:16: Error: Type variables can't be used in static members.
+//   @Class<Class<T>>()
+//                ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:37:6: Error: Type variables can't be used in static members.
+//   @A<T>()
+//      ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:46:8: Error: Type variables can't be used in static members.
+//   @A<A<T>>()
+//        ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:55:6: Error: Type variables can't be used in static members.
+//   @B<T>()
+//      ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:64:8: Error: Type variables can't be used in static members.
+//   @A<B<T>>()
+//        ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:79:4: Error: Couldn't find constructor 'T'.
+//   @T()
+//    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:82:10: Error: Type variables can't be used in static members.
+//   @Class<T>()
+//          ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:85:16: Error: Type variables can't be used in static members.
+//   @Class<Class<T>>()
+//                ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:88:6: Error: Type variables can't be used in static members.
+//   @A<T>()
+//      ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:91:6: Error: Type variables can't be used in static members.
+//   @B<T>()
+//      ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:94:4: Error: Couldn't find constructor 'T'.
+//   @T()
+//    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:97:4: Error: Couldn't find constructor 'T'.
+//   @T()
+//    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:109:4: Error: Couldn't find constructor 'T'.
+//   @T()
+//    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:112:4: Error: Couldn't find constructor 'T'.
+//   @T()
+//    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:115:4: Error: Couldn't find constructor 'T'.
+//   @T()
+//    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:122:4: Error: Couldn't find constructor 'T'.
+//   @T()
+//    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:134:4: Error: Couldn't find constructor 'T'.
+//   @T()
+//    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:137:4: Error: Couldn't find constructor 'T'.
+//   @T()
+//    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:144:4: Error: Couldn't find constructor 'T'.
+//   @T()
+//    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:147:4: Error: Couldn't find constructor 'T'.
+//   @T()
+//    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:14:5: Error: Type variables can't be used in static members.
+//     T? local;
+//     ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:15:5: Error: Type variables can't be used in static members.
+//     T;
+//     ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:16:24: Error: Type variables can't be used in static members.
+//     void fun<U extends T>() {}
+//                        ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:21:11: Error: Type variables can't be used in static members.
+//     Class<T>? local;
+//           ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:22:15: Error: Type variables can't be used in static members.
+//     new Class<T>();
+//               ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:23:11: Error: Type variables can't be used in static members.
+//     Class<T>;
+//           ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:24:11: Error: Type variables can't be used in static members.
+//     Class<T>.new;
+//           ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:25:30: Error: Type variables can't be used in static members.
+//     void fun<U extends Class<T>>() {}
+//                              ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:30:17: Error: Type variables can't be used in static members.
+//     Class<Class<T>>? local;
+//                 ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:31:21: Error: Type variables can't be used in static members.
+//     new Class<Class<T>>();
+//                     ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:32:17: Error: Type variables can't be used in static members.
+//     Class<Class<T>>;
+//                 ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:33:17: Error: Type variables can't be used in static members.
+//     Class<Class<T>>.new;
+//                 ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:34:36: Error: Type variables can't be used in static members.
+//     void fun<U extends Class<Class<T>>>() {}
+//                                    ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:39:7: Error: Type variables can't be used in static members.
+//     A<T>? local;
+//       ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:40:11: Error: Type variables can't be used in static members.
+//     new A<T>();
+//           ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:41:7: Error: Type variables can't be used in static members.
+//     A<T>;
+//       ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:42:7: Error: Type variables can't be used in static members.
+//     A<T>.new;
+//       ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:43:26: Error: Type variables can't be used in static members.
+//     void fun<U extends A<T>>() {}
+//                          ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:48:9: Error: Type variables can't be used in static members.
+//     A<A<T>>? local;
+//         ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:49:13: Error: Type variables can't be used in static members.
+//     new A<A<T>>();
+//             ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:50:9: Error: Type variables can't be used in static members.
+//     A<A<T>>;
+//         ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:51:9: Error: Type variables can't be used in static members.
+//     A<A<T>>.new;
+//         ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:52:28: Error: Type variables can't be used in static members.
+//     void fun<U extends A<A<T>>>() {}
+//                            ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:57:7: Error: Type variables can't be used in static members.
+//     B<T>? local;
+//       ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:58:11: Error: Type variables can't be used in static members.
+//     new B<T>();
+//           ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:59:7: Error: Type variables can't be used in static members.
+//     B<T>;
+//       ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:60:7: Error: Type variables can't be used in static members.
+//     B<T>.new;
+//       ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:61:26: Error: Type variables can't be used in static members.
+//     void fun<U extends B<T>>() {}
+//                          ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:66:9: Error: Type variables can't be used in static members.
+//     A<B<T>>? local;
+//         ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:67:13: Error: Type variables can't be used in static members.
+//     new A<B<T>>();
+//             ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:68:9: Error: Type variables can't be used in static members.
+//     A<B<T>>;
+//         ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:69:9: Error: Type variables can't be used in static members.
+//     A<B<T>>.new;
+//         ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:70:28: Error: Type variables can't be used in static members.
+//     void fun<U extends A<B<T>>>() {}
+//                            ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:75:29: Error: Type variables can't be used in static members.
+//     void Function<S extends T>()? local;
+//                             ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:76:48: Error: Type variables can't be used in static members.
+//     void fun<V extends void Function<S extends T>()>() {}
+//                                                ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:86:24: Error: Type variables can't be used in static members.
+//   static Type field2 = T;
+//                        ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:89:30: Error: Type variables can't be used in static members.
+//   static Type field3 = Class<T>;
+//                              ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:117:5: Error: Type variables can't be used in static members.
+//     T? local;
+//     ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:118:5: Error: Type variables can't be used in static members.
+//     T;
+//     ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:119:24: Error: Type variables can't be used in static members.
+//     void fun<U extends T>() {}
+//                        ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:132:30: Error: The value 'null' can't be returned from a function with return type 'Mixin<T>' because 'Mixin<T>' is not nullable.
+//  - 'Mixin' is from 'pkg/front_end/testcases/general/type_variable_in_static_context.dart'.
+//   factory Mixin.fact(T t) => null;
+//                              ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:139:5: Error: Type variables can't be used in static members.
+//     T? local;
+//     ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:140:5: Error: Type variables can't be used in static members.
+//     T;
+//     ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:141:24: Error: Type variables can't be used in static members.
+//     void fun<U extends T>() {}
+//                        ^
+//
+// pkg/front_end/testcases/general/type_variable_in_static_context.dart:95:12: Error: Final field 'instanceField' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final T? instanceField;
+//            ^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef A<T extends core::Object? = dynamic> = self::Class<T%>;
+typedef B<T extends core::num> = self::Class<T>;
+class Class<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  @invalid-expression "pkg/front_end/testcases/general/type_variable_in_static_context.dart:79:4: Error: Couldn't find constructor 'T'.
+  @T()
+   ^"
+  static field invalid-type field0 = null;
+  @#C2
+  static field self::Class<invalid-type>? field1 = null;
+  @#C3
+  static field core::Type field2 = #C4;
+  @#C2
+  static field core::Type field3 = #C5;
+  @#C2
+  static field (invalid-type) → core::Type field4 = (invalid-type t) → core::Type => #C4;
+  @invalid-expression "pkg/front_end/testcases/general/type_variable_in_static_context.dart:94:4: Error: Couldn't find constructor 'T'.
+  @T()
+   ^"
+  final field self::Class::T? instanceField = null;
+  const constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  @invalid-expression "pkg/front_end/testcases/general/type_variable_in_static_context.dart:12:4: Error: Couldn't find constructor 'T'.
+  @T()
+   ^"
+  static method method0<S extends invalid-type>(invalid-type arg) → invalid-type {
+    invalid-type local;
+    #C4;
+    function fun<U extends invalid-type>() → void {}
+  }
+  @#C2
+  static method method1<S extends self::Class<invalid-type>>(self::Class<invalid-type> arg) → self::Class<invalid-type>? {
+    self::Class<invalid-type>? local;
+    new self::Class::•<invalid-type>();
+    #C5;
+    #C7;
+    function fun<U extends self::Class<invalid-type>>() → void {}
+  }
+  @#C3
+  static method method2<S extends self::Class<self::Class<invalid-type>>>(self::Class<self::Class<invalid-type>> arg) → self::Class<self::Class<invalid-type>>? {
+    self::Class<self::Class<invalid-type>>? local;
+    new self::Class::•<self::Class<invalid-type>>();
+    #C8;
+    #C9;
+    function fun<U extends self::Class<self::Class<invalid-type>>>() → void {}
+  }
+  @#C2
+  static method method3<S extends self::Class<invalid-type>>(self::Class<invalid-type> arg) → self::Class<invalid-type>? {
+    self::Class<invalid-type>? local;
+    new self::Class::•<invalid-type>();
+    #C5;
+    #C7;
+    function fun<U extends self::Class<invalid-type>>() → void {}
+  }
+  @#C3
+  static method method4<S extends self::Class<self::Class<invalid-type>>>(self::Class<self::Class<invalid-type>> arg) → self::Class<self::Class<invalid-type>>? {
+    self::Class<self::Class<invalid-type>>? local;
+    new self::Class::•<self::Class<invalid-type>>();
+    #C8;
+    #C9;
+    function fun<U extends self::Class<self::Class<invalid-type>>>() → void {}
+  }
+  @#C2
+  static method method5<S extends self::Class<invalid-type>>(self::Class<invalid-type> arg) → self::Class<invalid-type>? {
+    self::Class<invalid-type>? local;
+    new self::Class::•<invalid-type>();
+    #C5;
+    #C7;
+    function fun<U extends self::Class<invalid-type>>() → void {}
+  }
+  @#C3
+  static method method6<S extends self::Class<self::Class<invalid-type>>>(self::Class<self::Class<invalid-type>> arg) → self::Class<self::Class<invalid-type>>? {
+    self::Class<self::Class<invalid-type>>? local;
+    new self::Class::•<self::Class<invalid-type>>();
+    #C8;
+    #C9;
+    function fun<U extends self::Class<self::Class<invalid-type>>>() → void {}
+  }
+  @#C10
+  static method method7<U extends <S extends invalid-type = dynamic>() → void>(<S extends invalid-type = dynamic>() → void arg) → <S extends invalid-type = dynamic>() →? void {
+    <S extends invalid-type>() →? void local;
+    function fun<V extends <S extends invalid-type>() → void>() → void {}
+  }
+  @invalid-expression "pkg/front_end/testcases/general/type_variable_in_static_context.dart:97:4: Error: Couldn't find constructor 'T'.
+  @T()
+   ^"
+  method instanceMethod<covariant-by-class S extends self::Class::T%>(covariant-by-class self::Class::T% t) → self::Class::T% {
+    self::Class::T%;
+    return t;
+  }
+}
+abstract class Mixin<T extends core::Object? = dynamic> extends core::Object /*isMixinDeclaration*/  {
+  @invalid-expression "pkg/front_end/testcases/general/type_variable_in_static_context.dart:134:4: Error: Couldn't find constructor 'T'.
+  @T()
+   ^"
+  static field invalid-type field0 = null;
+  @invalid-expression "pkg/front_end/testcases/general/type_variable_in_static_context.dart:144:4: Error: Couldn't find constructor 'T'.
+  @T()
+   ^"
+  covariant-by-class field self::Mixin::T? instanceField = null;
+  constructor •(invalid-type t) → self::Mixin<self::Mixin::T%>
+    : super core::Object::•()
+    ;
+  static factory fact<T extends core::Object? = dynamic>(self::Mixin::fact::T% t) → self::Mixin<self::Mixin::fact::T%>
+    return invalid-expression "pkg/front_end/testcases/general/type_variable_in_static_context.dart:132:30: Error: The value 'null' can't be returned from a function with return type 'Mixin<T>' because 'Mixin<T>' is not nullable.
+ - 'Mixin' is from 'pkg/front_end/testcases/general/type_variable_in_static_context.dart'.
+  factory Mixin.fact(T t) => null;
+                             ^" in null as{TypeError,ForNonNullableByDefault} Never;
+  @invalid-expression "pkg/front_end/testcases/general/type_variable_in_static_context.dart:137:4: Error: Couldn't find constructor 'T'.
+  @T()
+   ^"
+  static method staticMethod<S extends invalid-type>(invalid-type arg) → invalid-type {
+    invalid-type local;
+    #C4;
+    function fun<U extends invalid-type>() → void {}
+  }
+  @invalid-expression "pkg/front_end/testcases/general/type_variable_in_static_context.dart:147:4: Error: Couldn't find constructor 'T'.
+  @T()
+   ^"
+  method instanceMethod<covariant-by-class S extends self::Mixin::T%>(covariant-by-class self::Mixin::T% t) → self::Mixin::T% {
+    self::Mixin::T%;
+    return t;
+  }
+}
+extension Extension<T extends core::Object? = dynamic> on T% {
+  static field field0 = self::Extension|field0;
+  field field1 = self::Extension|field1;
+  static method staticMethod = self::Extension|staticMethod;
+  method instanceMethod = self::Extension|instanceMethod;
+  tearoff instanceMethod = self::Extension|get#instanceMethod;
+}
+@invalid-expression "pkg/front_end/testcases/general/type_variable_in_static_context.dart:109:4: Error: Couldn't find constructor 'T'.
+  @T()
+   ^"
+static field invalid-type Extension|field0;
+@invalid-expression "pkg/front_end/testcases/general/type_variable_in_static_context.dart:112:4: Error: Couldn't find constructor 'T'.
+  @T()
+   ^"
+static field invalid-type Extension|field1;
+@invalid-expression "pkg/front_end/testcases/general/type_variable_in_static_context.dart:115:4: Error: Couldn't find constructor 'T'.
+  @T()
+   ^"
+static method Extension|staticMethod<S extends invalid-type>(invalid-type arg) → invalid-type {
+  invalid-type local;
+  #C4;
+  function fun<U extends invalid-type>() → void {}
+}
+@invalid-expression "pkg/front_end/testcases/general/type_variable_in_static_context.dart:122:4: Error: Couldn't find constructor 'T'.
+  @T()
+   ^"
+static method Extension|instanceMethod<T extends core::Object? = dynamic, S extends self::Extension|instanceMethod::T% = dynamic>(lowered final self::Extension|instanceMethod::T% #this, self::Extension|instanceMethod::T% t) → self::Extension|instanceMethod::T% {
+  self::Extension|instanceMethod::T%;
+  return t;
+}
+static method Extension|get#instanceMethod<T extends core::Object? = dynamic>(lowered final self::Extension|get#instanceMethod::T% #this) → <S extends self::Extension|get#instanceMethod::T% = dynamic>(self::Extension|get#instanceMethod::T%) → self::Extension|get#instanceMethod::T%
+  return <S extends self::Extension|get#instanceMethod::T% = dynamic>(self::Extension|get#instanceMethod::T% t) → self::Extension|get#instanceMethod::T% => self::Extension|instanceMethod<self::Extension|get#instanceMethod::T%, S%>(#this, t);
+static method main() → dynamic {}
+static method _#B#new#tearOff<T extends core::num>() → self::Class<self::_#B#new#tearOff::T>
+  return new self::Class::•<self::_#B#new#tearOff::T>();
+
+constants  {
+  #C1 = null
+  #C2 = self::Class<invalid-type> {instanceField:#C1}
+  #C3 = self::Class<self::Class<invalid-type>*> {instanceField:#C1}
+  #C4 = TypeLiteralConstant(invalid-type)
+  #C5 = TypeLiteralConstant(self::Class<invalid-type>*)
+  #C6 = constructor-tearoff self::Class::•
+  #C7 = instantiation #C6 <invalid-type>
+  #C8 = TypeLiteralConstant(self::Class<self::Class<invalid-type>*>*)
+  #C9 = instantiation #C6 <self::Class<invalid-type>*>
+  #C10 = self::Class<<S extends invalid-type>() →* void> {instanceField:#C1}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///type_variable_in_static_context.dart:
+- Class. (from org-dartlang-testcase:///type_variable_in_static_context.dart:10:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/type_variable_prefix.dart.weak.modular.expect b/pkg/front_end/testcases/general/type_variable_prefix.dart.weak.modular.expect
new file mode 100644
index 0000000..20eabce
--- /dev/null
+++ b/pkg/front_end/testcases/general/type_variable_prefix.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/type_variable_prefix.dart:10:3: Error: 'T.String' can't be used as a type because 'T' doesn't refer to an import prefix.
+//   T.String method() => "Hello, World!";
+//   ^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "dart:core" as T;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method method() → invalid-type
+    return "Hello, World!";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::String* s = new self::C::•<dynamic>().{self::C::method}(){() →* invalid-type};
+  core::print(s);
+}
diff --git a/pkg/front_end/testcases/general/type_variable_uses.dart.weak.modular.expect b/pkg/front_end/testcases/general/type_variable_uses.dart.weak.modular.expect
new file mode 100644
index 0000000..4fbbbaa
--- /dev/null
+++ b/pkg/front_end/testcases/general/type_variable_uses.dart.weak.modular.expect
@@ -0,0 +1,120 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/type_variable_uses.dart:7:12: Error: Type variables can't be used in static members.
+//   static C<T> staticMethod() {
+//            ^
+//
+// pkg/front_end/testcases/general/type_variable_uses.dart:8:11: Error: Type variables can't be used in static members.
+//     print(T);
+//           ^
+//
+// pkg/front_end/testcases/general/type_variable_uses.dart:9:5: Error: Type variables can't be used in static members.
+//     T t;
+//     ^
+//
+// pkg/front_end/testcases/general/type_variable_uses.dart:10:7: Error: Type variables can't be used in static members.
+//     C<T> l;
+//       ^
+//
+// pkg/front_end/testcases/general/type_variable_uses.dart:11:9: Error: Type variables can't be used in static members.
+//     C<C<T>> ll;
+//         ^
+//
+// pkg/front_end/testcases/general/type_variable_uses.dart:12:13: Error: Type variables can't be used in static members.
+//     const C<T>();
+//             ^
+//
+// pkg/front_end/testcases/general/type_variable_uses.dart:13:12: Error: Type variables can't be used in static members.
+//     const <T>[];
+//            ^
+//
+// pkg/front_end/testcases/general/type_variable_uses.dart:14:14: Error: Type variables can't be used in static members.
+//     const <C<T>>[];
+//              ^
+//
+// pkg/front_end/testcases/general/type_variable_uses.dart:15:20: Error: Type variables can't be used in static members.
+//     const <Object>[T];
+//                    ^
+//
+// pkg/front_end/testcases/general/type_variable_uses.dart:16:28: Error: Type variables can't be used in static members.
+//     const <Object>[const C<T>()];
+//                            ^
+//
+// pkg/front_end/testcases/general/type_variable_uses.dart:24:13: Error: Type variables can't be used as constants.
+//     const C<T>();
+//             ^
+//
+// pkg/front_end/testcases/general/type_variable_uses.dart:25:12: Error: Type variables can't be used as constants.
+//     const <T>[];
+//            ^
+//
+// pkg/front_end/testcases/general/type_variable_uses.dart:26:14: Error: Type variables can't be used as constants.
+//     const <C<T>>[];
+//              ^
+//
+// pkg/front_end/testcases/general/type_variable_uses.dart:27:20: Error: Type variables can't be used as constants.
+//     const <Object>[T];
+//                    ^
+//
+// pkg/front_end/testcases/general/type_variable_uses.dart:28:28: Error: Type variables can't be used as constants.
+//     const <Object>[const C<T>()];
+//                            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  static method staticMethod() → self::C<invalid-type>* {
+    core::print(#C1);
+    invalid-type t;
+    self::C<invalid-type>* l;
+    self::C<self::C<invalid-type>*>* ll;
+    #C2;
+    #C3;
+    #C4;
+    #C5;
+    #C6;
+  }
+  method instanceMethod() → self::C<self::C::T*>* {
+    core::print(self::C::T*);
+    self::C::T* t;
+    self::C<self::C::T*>* l;
+    self::C<self::C<self::C::T*>*>* ll;
+    #C2;
+    #C3;
+    #C4;
+    #C5;
+    #C6;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = TypeLiteralConstant(invalid-type)
+  #C2 = self::C<invalid-type> {}
+  #C3 = <invalid-type>[]
+  #C4 = <self::C<invalid-type>*>[]
+  #C5 = <core::Object*>[#C1]
+  #C6 = <core::Object*>[#C2]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///type_variable_uses.dart:
+- C. (from org-dartlang-testcase:///type_variable_uses.dart:6:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/typedef.dart.weak.modular.expect b/pkg/front_end/testcases/general/typedef.dart.weak.modular.expect
new file mode 100644
index 0000000..2b36abf
--- /dev/null
+++ b/pkg/front_end/testcases/general/typedef.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef _NullaryFunction = () →* dynamic;
+typedef _UnaryFunction = (dynamic) →* dynamic;
+typedef _BinaryFunction = (dynamic, dynamic) →* dynamic;
+static method main() → dynamic {
+  core::print(#C1 is () →* dynamic);
+  core::print(#C1 is (dynamic) →* dynamic);
+  core::print(#C1 is (dynamic, dynamic) →* dynamic);
+}
+
+constants  {
+  #C1 = static-tearoff self::main
+}
diff --git a/pkg/front_end/testcases/general/typedef_annotation.dart.weak.modular.expect b/pkg/front_end/testcases/general/typedef_annotation.dart.weak.modular.expect
new file mode 100644
index 0000000..3c94843
--- /dev/null
+++ b/pkg/front_end/testcases/general/typedef_annotation.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+@#C1
+typedef F = () → void;
+@#C1
+typedef G = () → void;
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::A {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///typedef_annotation.dart:
+- A. (from org-dartlang-testcase:///typedef_annotation.dart:6:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/undefined.dart.weak.modular.expect b/pkg/front_end/testcases/general/undefined.dart.weak.modular.expect
new file mode 100644
index 0000000..0c68639
--- /dev/null
+++ b/pkg/front_end/testcases/general/undefined.dart.weak.modular.expect
@@ -0,0 +1,63 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/undefined.dart:12:5: Error: The getter 'y' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/general/undefined.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'y'.
+//   c.y;
+//     ^
+//
+// pkg/front_end/testcases/general/undefined.dart:14:5: Error: The method 'g' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/general/undefined.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'g'.
+//   c.g();
+//     ^
+//
+// pkg/front_end/testcases/general/undefined.dart:16:5: Error: The setter 'y' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/general/undefined.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'y'.
+//   c.y = null;
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field dynamic x = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test(self::C* c) → void {
+  c.{self::C::x}{dynamic};
+  invalid-expression "pkg/front_end/testcases/general/undefined.dart:12:5: Error: The getter 'y' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/general/undefined.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'y'.
+  c.y;
+    ^" in c{<unresolved>}.y;
+  c.{self::C::f}(){() →* void};
+  invalid-expression "pkg/front_end/testcases/general/undefined.dart:14:5: Error: The method 'g' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/general/undefined.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'g'.
+  c.g();
+    ^" in c{<unresolved>}.g();
+  c.{self::C::x} = null;
+  invalid-expression "pkg/front_end/testcases/general/undefined.dart:16:5: Error: The setter 'y' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/general/undefined.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'y'.
+  c.y = null;
+    ^" in c{<unresolved>}.y = null;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/undefined_getter_in_compound_assignment.dart.weak.modular.expect b/pkg/front_end/testcases/general/undefined_getter_in_compound_assignment.dart.weak.modular.expect
new file mode 100644
index 0000000..fdcdf1e
--- /dev/null
+++ b/pkg/front_end/testcases/general/undefined_getter_in_compound_assignment.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/undefined_getter_in_compound_assignment.dart:11:5: Error: The getter 'x' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/general/undefined_getter_in_compound_assignment.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'x'.
+//   c.x += 1;
+//     ^
+//
+// pkg/front_end/testcases/general/undefined_getter_in_compound_assignment.dart:12:5: Error: The getter 'x' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/general/undefined_getter_in_compound_assignment.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'x'.
+//   c.x ??= 1;
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  set x(dynamic value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test(self::C* c) → void {
+  c.{self::C::x} = 1;
+  let final self::C* #t1 = c in #t1.{self::C::x} = invalid-expression "pkg/front_end/testcases/general/undefined_getter_in_compound_assignment.dart:11:5: Error: The getter 'x' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/general/undefined_getter_in_compound_assignment.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'x'.
+  c.x += 1;
+    ^" in #t1{<unresolved>}.x{dynamic}.+(1);
+  let final self::C* #t2 = c in invalid-expression "pkg/front_end/testcases/general/undefined_getter_in_compound_assignment.dart:12:5: Error: The getter 'x' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/general/undefined_getter_in_compound_assignment.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'x'.
+  c.x ??= 1;
+    ^" in #t2{<unresolved>}.x == null ?{dynamic} #t2.{self::C::x} = 1 : null;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/uninitialized_fields.dart.weak.modular.expect b/pkg/front_end/testcases/general/uninitialized_fields.dart.weak.modular.expect
new file mode 100644
index 0000000..66c109b
--- /dev/null
+++ b/pkg/front_end/testcases/general/uninitialized_fields.dart.weak.modular.expect
@@ -0,0 +1,77 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Uninitialized extends core::Object {
+  field core::int* x = null;
+  synthetic constructor •() → self::Uninitialized*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class PartiallyInitialized extends core::Object {
+  field core::int* x;
+  constructor •(core::int* x) → self::PartiallyInitialized*
+    : self::PartiallyInitialized::x = x, super core::Object::•()
+    ;
+  constructor noInitializer() → self::PartiallyInitialized*
+    : self::PartiallyInitialized::x = null, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Initialized extends core::Object {
+  field core::int* x;
+  constructor •(core::int* x) → self::Initialized*
+    : self::Initialized::x = x, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Forwarding extends core::Object {
+  field core::int* x;
+  constructor initialize(core::int* x) → self::Forwarding*
+    : self::Forwarding::x = x, super core::Object::•()
+    ;
+  constructor •(core::int* arg) → self::Forwarding*
+    : this self::Forwarding::initialize(arg)
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* uninitializedTopLevel;
+static field core::int* initializedTopLevel = 4;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/unresolved_constructor_invocation.dart.weak.modular.expect b/pkg/front_end/testcases/general/unresolved_constructor_invocation.dart.weak.modular.expect
new file mode 100644
index 0000000..63b12b9
--- /dev/null
+++ b/pkg/front_end/testcases/general/unresolved_constructor_invocation.dart.weak.modular.expect
@@ -0,0 +1,866 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:14:26: Error: Superclass has no constructor named 'Super'.
+//   Class.constructor1() : super();
+//                          ^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:15:26: Error: Superclass has no constructor named 'Super.unresolved'.
+//   Class.constructor2() : super.unresolved();
+//                          ^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:16:26: Error: Couldn't find constructor 'Class'.
+//   Class.constructor3() : this();
+//                          ^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:17:26: Error: Couldn't find constructor 'Class.unresolved'.
+//   Class.constructor4() : this.unresolved();
+//                          ^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:25:3: Error: Method not found: 'UnresolvedClass'.
+//   UnresolvedClass();
+//   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:26:7: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new UnresolvedClass();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:27:9: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const UnresolvedClass();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:29:3: Error: Undefined name 'UnresolvedClass'.
+//   UnresolvedClass.unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:30:7: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+//   new UnresolvedClass.unresolvedConstructor();
+//       ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:31:9: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+//   const UnresolvedClass.unresolvedConstructor();
+//         ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:32:3: Error: Undefined name 'UnresolvedClass'.
+//   UnresolvedClass /**/ .unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:33:7: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+//   new UnresolvedClass. /**/ unresolvedConstructor();
+//       ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:34:9: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+//   const UnresolvedClass /**/ .unresolvedConstructor();
+//         ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:36:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix.UnresolvedClass();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:37:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   new unresolved_prefix.UnresolvedClass();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:38:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   const unresolved_prefix.UnresolvedClass();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:39:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix. /**/ UnresolvedClass();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:40:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   new unresolved_prefix /**/ .UnresolvedClass();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:41:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   const unresolved_prefix. /**/ UnresolvedClass();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:43:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix.UnresolvedClass.unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:44:41: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   new unresolved_prefix.UnresolvedClass.unresolvedConstructor();
+//                                         ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:45:43: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   const unresolved_prefix.UnresolvedClass.unresolvedConstructor();
+//                                           ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:46:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix /**/ .UnresolvedClass.unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:47:47: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   new unresolved_prefix.UnresolvedClass /**/ .unresolvedConstructor();
+//                                               ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:48:55: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   const unresolved_prefix. /**/ UnresolvedClass. /**/ unresolvedConstructor();
+//                                                       ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:50:3: Error: Method not found: 'UnresolvedClass'.
+//   UnresolvedClass<int>();
+//   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:51:7: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new UnresolvedClass<int>();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:52:9: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const UnresolvedClass<int>();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:53:3: Error: Method not found: 'UnresolvedClass'.
+//   UnresolvedClass /**/ <int>();
+//   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:54:7: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new UnresolvedClass<int> /**/ ();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:55:9: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const UnresolvedClass /**/ <int>();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:57:3: Error: Couldn't find constructor 'UnresolvedClass'.
+//   UnresolvedClass<int>.unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:58:7: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new UnresolvedClass<int>.unresolvedConstructor();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:59:9: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const UnresolvedClass<int>.unresolvedConstructor();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:60:3: Error: Couldn't find constructor 'UnresolvedClass'.
+//   UnresolvedClass /**/ <int>.unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:61:7: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new UnresolvedClass<int> /**/ .unresolvedConstructor();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:62:9: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const UnresolvedClass<int>. /**/ unresolvedConstructor();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:64:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix.UnresolvedClass<int>();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:65:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   new unresolved_prefix.UnresolvedClass<int>();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:66:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   const unresolved_prefix.UnresolvedClass<int>();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:67:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix /**/ .UnresolvedClass<int>();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:68:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   new unresolved_prefix.UnresolvedClass /**/ <int>();
+//       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:69:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+//   const unresolved_prefix.UnresolvedClass<int> /**/ ();
+//         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:71:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:71:42: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+//   unresolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+//                                          ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:72:46: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   new unresolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+//                                              ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:73:48: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   const unresolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+//                                                ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:74:3: Error: Undefined name 'unresolved_prefix'.
+//   unresolved_prefix /**/ .UnresolvedClass<int>.unresolvedConstructor();
+//   ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:74:48: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+//   unresolved_prefix /**/ .UnresolvedClass<int>.unresolvedConstructor();
+//                                                ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:75:52: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   new unresolved_prefix.UnresolvedClass /**/ <int>.unresolvedConstructor();
+//                                                    ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:76:54: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+//   const unresolved_prefix.UnresolvedClass<int>. /**/ unresolvedConstructor();
+//                                                      ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:78:3: Error: Couldn't find constructor 'ResolvedClass'.
+//   ResolvedClass();
+//   ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:79:7: Error: Couldn't find constructor 'ResolvedClass'.
+//   new ResolvedClass();
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:80:9: Error: Couldn't find constructor 'ResolvedClass'.
+//   const ResolvedClass();
+//         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:82:17: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+//   ResolvedClass.unresolvedConstructor();
+//                 ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:83:21: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new ResolvedClass.unresolvedConstructor();
+//                     ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:84:23: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const ResolvedClass.unresolvedConstructor();
+//                       ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:85:23: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+//   ResolvedClass /**/ .unresolvedConstructor();
+//                       ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:86:27: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new ResolvedClass. /**/ unresolvedConstructor();
+//                           ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:87:29: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const ResolvedClass /**/ .unresolvedConstructor();
+//                             ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:89:19: Error: Method not found: 'UnresolvedClass'.
+//   resolved_prefix.UnresolvedClass();
+//                   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:90:23: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix.UnresolvedClass();
+//                       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:91:25: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const resolved_prefix.UnresolvedClass();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:92:25: Error: Method not found: 'UnresolvedClass'.
+//   resolved_prefix. /**/ UnresolvedClass();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:93:29: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix /**/ .UnresolvedClass();
+//                             ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:94:31: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const resolved_prefix. /**/ UnresolvedClass();
+//                               ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:96:19: Error: Couldn't find constructor 'ResolvedClass'.
+//   resolved_prefix.ResolvedClass();
+//                   ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:97:7: Error: Couldn't find constructor 'ResolvedClass'.
+//   new resolved_prefix.ResolvedClass();
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:98:9: Error: Couldn't find constructor 'ResolvedClass'.
+//   const resolved_prefix.ResolvedClass();
+//         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:99:25: Error: Couldn't find constructor 'ResolvedClass'.
+//   resolved_prefix. /**/ ResolvedClass();
+//                         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:100:7: Error: Couldn't find constructor 'ResolvedClass'.
+//   new resolved_prefix /**/ .ResolvedClass();
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:101:9: Error: Couldn't find constructor 'ResolvedClass'.
+//   const resolved_prefix. /**/ ResolvedClass();
+//         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:103:19: Error: Undefined name 'UnresolvedClass'.
+//   resolved_prefix.UnresolvedClass.unresolvedConstructor();
+//                   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:104:23: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix.UnresolvedClass.unresolvedConstructor();
+//                       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:105:25: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const resolved_prefix.UnresolvedClass.unresolvedConstructor();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:106:25: Error: Undefined name 'UnresolvedClass'.
+//   resolved_prefix /**/ .UnresolvedClass.unresolvedConstructor();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:107:23: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix.UnresolvedClass /**/ .unresolvedConstructor();
+//                       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:108:31: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const resolved_prefix. /**/ UnresolvedClass. /**/ unresolvedConstructor();
+//                               ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:110:33: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+//   resolved_prefix.ResolvedClass.unresolvedConstructor();
+//                                 ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:111:37: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new resolved_prefix.ResolvedClass.unresolvedConstructor();
+//                                     ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:112:39: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const resolved_prefix.ResolvedClass.unresolvedConstructor();
+//                                       ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:113:39: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+//   resolved_prefix /**/ .ResolvedClass.unresolvedConstructor();
+//                                       ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:114:43: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new resolved_prefix.ResolvedClass /**/ .unresolvedConstructor();
+//                                           ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:115:51: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const resolved_prefix. /**/ ResolvedClass. /**/ unresolvedConstructor();
+//                                                   ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:117:3: Error: Couldn't find constructor 'ResolvedClass'.
+//   ResolvedClass<int>();
+//   ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:118:7: Error: Couldn't find constructor 'ResolvedClass'.
+//   new ResolvedClass<int>();
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:119:9: Error: Couldn't find constructor 'ResolvedClass'.
+//   const ResolvedClass<int>();
+//         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:120:3: Error: Couldn't find constructor 'ResolvedClass'.
+//   ResolvedClass /**/ <int>();
+//   ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:121:7: Error: Couldn't find constructor 'ResolvedClass'.
+//   new ResolvedClass /**/ <int>();
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:122:9: Error: Couldn't find constructor 'ResolvedClass'.
+//   const ResolvedClass /**/ <int>();
+//         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:124:22: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   ResolvedClass<int>.unresolvedConstructor();
+//                      ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:125:26: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new ResolvedClass<int>.unresolvedConstructor();
+//                          ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:126:28: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const ResolvedClass<int>.unresolvedConstructor();
+//                            ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:127:28: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   ResolvedClass<int> /**/ .unresolvedConstructor();
+//                            ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:128:32: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new ResolvedClass<int>. /**/ unresolvedConstructor();
+//                                ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:129:34: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const ResolvedClass /**/ <int>.unresolvedConstructor();
+//                                  ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:131:19: Error: Method not found: 'UnresolvedClass'.
+//   resolved_prefix.UnresolvedClass<int>();
+//                   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:132:23: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix.UnresolvedClass<int>();
+//                       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:133:25: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const resolved_prefix.UnresolvedClass<int>();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:134:25: Error: Method not found: 'UnresolvedClass'.
+//   resolved_prefix. /**/ UnresolvedClass<int>();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:135:23: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix.UnresolvedClass /**/ <int>();
+//                       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:136:25: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const resolved_prefix.UnresolvedClass<int> /**/ ();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:138:19: Error: Couldn't find constructor 'ResolvedClass'.
+//   resolved_prefix.ResolvedClass<int>();
+//                   ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:139:7: Error: Couldn't find constructor 'ResolvedClass'.
+//   new resolved_prefix.ResolvedClass<int>();
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:140:9: Error: Couldn't find constructor 'ResolvedClass'.
+//   const resolved_prefix.ResolvedClass<int>();
+//         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:141:25: Error: Couldn't find constructor 'ResolvedClass'.
+//   resolved_prefix. /**/ ResolvedClass<int>();
+//                         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:142:7: Error: Couldn't find constructor 'ResolvedClass'.
+//   new resolved_prefix.ResolvedClass /**/ <int>();
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:143:9: Error: Couldn't find constructor 'ResolvedClass'.
+//   const resolved_prefix.ResolvedClass<int> /**/ ();
+//         ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:145:19: Error: Couldn't find constructor 'UnresolvedClass'.
+//   resolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+//                   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:146:23: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+//                       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:147:25: Error: Couldn't find constructor 'UnresolvedClass'.
+//   const resolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:148:25: Error: Couldn't find constructor 'UnresolvedClass'.
+//   resolved_prefix /**/ .UnresolvedClass<int>.unresolvedConstructor();
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:149:23: Error: Couldn't find constructor 'UnresolvedClass'.
+//   new resolved_prefix.UnresolvedClass<int> /**/ .unresolvedConstructor();
+//                       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:151:14: Error: Couldn't find constructor 'UnresolvedClass'.
+//       . /**/ UnresolvedClass<int>. /**/ unresolvedConstructor();
+//              ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:153:38: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   resolved_prefix.ResolvedClass<int>.unresolvedConstructor();
+//                                      ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:154:42: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new resolved_prefix.ResolvedClass<int>.unresolvedConstructor();
+//                                          ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:155:44: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const resolved_prefix.ResolvedClass<int>.unresolvedConstructor();
+//                                            ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:156:44: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   resolved_prefix /**/ .ResolvedClass<int>.unresolvedConstructor();
+//                                            ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:157:48: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   new resolved_prefix.ResolvedClass<int> /**/ .unresolvedConstructor();
+//                                                ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:158:56: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+//   const resolved_prefix. /**/ ResolvedClass<int>. /**/ unresolvedConstructor();
+//                                                        ^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///unresolved_constructor_invocation.dart" as resolved_prefix;
+
+class Super extends core::Object {
+  constructor named() → self::Super
+    : super core::Object::•()
+    ;
+}
+class Class extends self::Super {
+  constructor constructor1() → self::Class
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:14:26: Error: Superclass has no constructor named 'Super'.
+  Class.constructor1() : super();
+                         ^^^^^"
+    ;
+  constructor constructor2() → self::Class
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:15:26: Error: Superclass has no constructor named 'Super.unresolved'.
+  Class.constructor2() : super.unresolved();
+                         ^^^^^"
+    ;
+  constructor constructor3() → self::Class
+    : final dynamic #t3 = invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:16:26: Error: Couldn't find constructor 'Class'.
+  Class.constructor3() : this();
+                         ^^^^"
+    ;
+  constructor constructor4() → self::Class
+    : final dynamic #t4 = invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:17:26: Error: Couldn't find constructor 'Class.unresolved'.
+  Class.constructor4() : this.unresolved();
+                         ^^^^"
+    ;
+}
+class ResolvedClass<T extends core::Object? = dynamic> extends core::Object {
+  constructor named() → self::ResolvedClass<self::ResolvedClass::T%>
+    : super core::Object::•()
+    ;
+}
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:25:3: Error: Method not found: 'UnresolvedClass'.
+  UnresolvedClass();
+  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:26:7: Error: Couldn't find constructor 'UnresolvedClass'.
+  new UnresolvedClass();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:27:9: Error: Couldn't find constructor 'UnresolvedClass'.
+  const UnresolvedClass();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:29:3: Error: Undefined name 'UnresolvedClass'.
+  UnresolvedClass.unresolvedConstructor();
+  ^^^^^^^^^^^^^^^"{dynamic}.unresolvedConstructor();
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:30:7: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+  new UnresolvedClass.unresolvedConstructor();
+      ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:31:9: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+  const UnresolvedClass.unresolvedConstructor();
+        ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:32:3: Error: Undefined name 'UnresolvedClass'.
+  UnresolvedClass /**/ .unresolvedConstructor();
+  ^^^^^^^^^^^^^^^"{dynamic}.unresolvedConstructor();
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:33:7: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+  new UnresolvedClass. /**/ unresolvedConstructor();
+      ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:34:9: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+  const UnresolvedClass /**/ .unresolvedConstructor();
+        ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:36:3: Error: Undefined name 'unresolved_prefix'.
+  unresolved_prefix.UnresolvedClass();
+  ^^^^^^^^^^^^^^^^^"{dynamic}.UnresolvedClass();
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:37:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  new unresolved_prefix.UnresolvedClass();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:38:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  const unresolved_prefix.UnresolvedClass();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:39:3: Error: Undefined name 'unresolved_prefix'.
+  unresolved_prefix. /**/ UnresolvedClass();
+  ^^^^^^^^^^^^^^^^^"{dynamic}.UnresolvedClass();
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:40:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  new unresolved_prefix /**/ .UnresolvedClass();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:41:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  const unresolved_prefix. /**/ UnresolvedClass();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:43:3: Error: Undefined name 'unresolved_prefix'.
+  unresolved_prefix.UnresolvedClass.unresolvedConstructor();
+  ^^^^^^^^^^^^^^^^^"{<invalid>}.UnresolvedClass{dynamic}.unresolvedConstructor();
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:44:41: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  new unresolved_prefix.UnresolvedClass.unresolvedConstructor();
+                                        ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:45:43: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  const unresolved_prefix.UnresolvedClass.unresolvedConstructor();
+                                          ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:46:3: Error: Undefined name 'unresolved_prefix'.
+  unresolved_prefix /**/ .UnresolvedClass.unresolvedConstructor();
+  ^^^^^^^^^^^^^^^^^"{<invalid>}.UnresolvedClass{dynamic}.unresolvedConstructor();
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:47:47: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  new unresolved_prefix.UnresolvedClass /**/ .unresolvedConstructor();
+                                              ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:48:55: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  const unresolved_prefix. /**/ UnresolvedClass. /**/ unresolvedConstructor();
+                                                      ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:50:3: Error: Method not found: 'UnresolvedClass'.
+  UnresolvedClass<int>();
+  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:51:7: Error: Couldn't find constructor 'UnresolvedClass'.
+  new UnresolvedClass<int>();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:52:9: Error: Couldn't find constructor 'UnresolvedClass'.
+  const UnresolvedClass<int>();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:53:3: Error: Method not found: 'UnresolvedClass'.
+  UnresolvedClass /**/ <int>();
+  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:54:7: Error: Couldn't find constructor 'UnresolvedClass'.
+  new UnresolvedClass<int> /**/ ();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:55:9: Error: Couldn't find constructor 'UnresolvedClass'.
+  const UnresolvedClass /**/ <int>();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:57:3: Error: Couldn't find constructor 'UnresolvedClass'.
+  UnresolvedClass<int>.unresolvedConstructor();
+  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:58:7: Error: Couldn't find constructor 'UnresolvedClass'.
+  new UnresolvedClass<int>.unresolvedConstructor();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:59:9: Error: Couldn't find constructor 'UnresolvedClass'.
+  const UnresolvedClass<int>.unresolvedConstructor();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:60:3: Error: Couldn't find constructor 'UnresolvedClass'.
+  UnresolvedClass /**/ <int>.unresolvedConstructor();
+  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:61:7: Error: Couldn't find constructor 'UnresolvedClass'.
+  new UnresolvedClass<int> /**/ .unresolvedConstructor();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:62:9: Error: Couldn't find constructor 'UnresolvedClass'.
+  const UnresolvedClass<int>. /**/ unresolvedConstructor();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:64:3: Error: Undefined name 'unresolved_prefix'.
+  unresolved_prefix.UnresolvedClass<int>();
+  ^^^^^^^^^^^^^^^^^"{dynamic}.UnresolvedClass<core::int>();
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:65:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  new unresolved_prefix.UnresolvedClass<int>();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:66:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  const unresolved_prefix.UnresolvedClass<int>();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:67:3: Error: Undefined name 'unresolved_prefix'.
+  unresolved_prefix /**/ .UnresolvedClass<int>();
+  ^^^^^^^^^^^^^^^^^"{dynamic}.UnresolvedClass<core::int>();
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:68:7: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  new unresolved_prefix.UnresolvedClass /**/ <int>();
+      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:69:9: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass'.
+  const unresolved_prefix.UnresolvedClass<int> /**/ ();
+        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:71:42: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+  unresolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+                                         ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:72:46: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  new unresolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+                                             ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:73:48: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  const unresolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+                                               ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:74:48: Error: Couldn't find constructor 'UnresolvedClass.unresolvedConstructor'.
+  unresolved_prefix /**/ .UnresolvedClass<int>.unresolvedConstructor();
+                                               ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:75:52: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  new unresolved_prefix.UnresolvedClass /**/ <int>.unresolvedConstructor();
+                                                   ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:76:54: Error: Couldn't find constructor 'unresolved_prefix.UnresolvedClass.unresolvedConstructor'.
+  const unresolved_prefix.UnresolvedClass<int>. /**/ unresolvedConstructor();
+                                                     ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:78:3: Error: Couldn't find constructor 'ResolvedClass'.
+  ResolvedClass();
+  ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:79:7: Error: Couldn't find constructor 'ResolvedClass'.
+  new ResolvedClass();
+      ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:80:9: Error: Couldn't find constructor 'ResolvedClass'.
+  const ResolvedClass();
+        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:82:17: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+  ResolvedClass.unresolvedConstructor();
+                ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:83:21: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new ResolvedClass.unresolvedConstructor();
+                    ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:84:23: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const ResolvedClass.unresolvedConstructor();
+                      ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:85:23: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+  ResolvedClass /**/ .unresolvedConstructor();
+                      ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:86:27: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new ResolvedClass. /**/ unresolvedConstructor();
+                          ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:87:29: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const ResolvedClass /**/ .unresolvedConstructor();
+                            ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:89:19: Error: Method not found: 'UnresolvedClass'.
+  resolved_prefix.UnresolvedClass();
+                  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:90:23: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix.UnresolvedClass();
+                      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:91:25: Error: Couldn't find constructor 'UnresolvedClass'.
+  const resolved_prefix.UnresolvedClass();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:92:25: Error: Method not found: 'UnresolvedClass'.
+  resolved_prefix. /**/ UnresolvedClass();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:93:29: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix /**/ .UnresolvedClass();
+                            ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:94:31: Error: Couldn't find constructor 'UnresolvedClass'.
+  const resolved_prefix. /**/ UnresolvedClass();
+                              ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:96:19: Error: Couldn't find constructor 'ResolvedClass'.
+  resolved_prefix.ResolvedClass();
+                  ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:97:7: Error: Couldn't find constructor 'ResolvedClass'.
+  new resolved_prefix.ResolvedClass();
+      ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:98:9: Error: Couldn't find constructor 'ResolvedClass'.
+  const resolved_prefix.ResolvedClass();
+        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:99:25: Error: Couldn't find constructor 'ResolvedClass'.
+  resolved_prefix. /**/ ResolvedClass();
+                        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:100:7: Error: Couldn't find constructor 'ResolvedClass'.
+  new resolved_prefix /**/ .ResolvedClass();
+      ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:101:9: Error: Couldn't find constructor 'ResolvedClass'.
+  const resolved_prefix. /**/ ResolvedClass();
+        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:103:19: Error: Undefined name 'UnresolvedClass'.
+  resolved_prefix.UnresolvedClass.unresolvedConstructor();
+                  ^^^^^^^^^^^^^^^"{dynamic}.unresolvedConstructor();
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:104:23: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix.UnresolvedClass.unresolvedConstructor();
+                      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:105:25: Error: Couldn't find constructor 'UnresolvedClass'.
+  const resolved_prefix.UnresolvedClass.unresolvedConstructor();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:106:25: Error: Undefined name 'UnresolvedClass'.
+  resolved_prefix /**/ .UnresolvedClass.unresolvedConstructor();
+                        ^^^^^^^^^^^^^^^"{dynamic}.unresolvedConstructor();
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:107:23: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix.UnresolvedClass /**/ .unresolvedConstructor();
+                      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:108:31: Error: Couldn't find constructor 'UnresolvedClass'.
+  const resolved_prefix. /**/ UnresolvedClass. /**/ unresolvedConstructor();
+                              ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:110:33: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+  resolved_prefix.ResolvedClass.unresolvedConstructor();
+                                ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:111:37: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new resolved_prefix.ResolvedClass.unresolvedConstructor();
+                                    ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:112:39: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const resolved_prefix.ResolvedClass.unresolvedConstructor();
+                                      ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:113:39: Error: Member not found: 'ResolvedClass.unresolvedConstructor'.
+  resolved_prefix /**/ .ResolvedClass.unresolvedConstructor();
+                                      ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:114:43: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new resolved_prefix.ResolvedClass /**/ .unresolvedConstructor();
+                                          ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:115:51: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const resolved_prefix. /**/ ResolvedClass. /**/ unresolvedConstructor();
+                                                  ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:117:3: Error: Couldn't find constructor 'ResolvedClass'.
+  ResolvedClass<int>();
+  ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:118:7: Error: Couldn't find constructor 'ResolvedClass'.
+  new ResolvedClass<int>();
+      ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:119:9: Error: Couldn't find constructor 'ResolvedClass'.
+  const ResolvedClass<int>();
+        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:120:3: Error: Couldn't find constructor 'ResolvedClass'.
+  ResolvedClass /**/ <int>();
+  ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:121:7: Error: Couldn't find constructor 'ResolvedClass'.
+  new ResolvedClass /**/ <int>();
+      ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:122:9: Error: Couldn't find constructor 'ResolvedClass'.
+  const ResolvedClass /**/ <int>();
+        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:124:22: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  ResolvedClass<int>.unresolvedConstructor();
+                     ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:125:26: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new ResolvedClass<int>.unresolvedConstructor();
+                         ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:126:28: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const ResolvedClass<int>.unresolvedConstructor();
+                           ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:127:28: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  ResolvedClass<int> /**/ .unresolvedConstructor();
+                           ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:128:32: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new ResolvedClass<int>. /**/ unresolvedConstructor();
+                               ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:129:34: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const ResolvedClass /**/ <int>.unresolvedConstructor();
+                                 ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:131:19: Error: Method not found: 'UnresolvedClass'.
+  resolved_prefix.UnresolvedClass<int>();
+                  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:132:23: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix.UnresolvedClass<int>();
+                      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:133:25: Error: Couldn't find constructor 'UnresolvedClass'.
+  const resolved_prefix.UnresolvedClass<int>();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:134:25: Error: Method not found: 'UnresolvedClass'.
+  resolved_prefix. /**/ UnresolvedClass<int>();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:135:23: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix.UnresolvedClass /**/ <int>();
+                      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:136:25: Error: Couldn't find constructor 'UnresolvedClass'.
+  const resolved_prefix.UnresolvedClass<int> /**/ ();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:138:19: Error: Couldn't find constructor 'ResolvedClass'.
+  resolved_prefix.ResolvedClass<int>();
+                  ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:139:7: Error: Couldn't find constructor 'ResolvedClass'.
+  new resolved_prefix.ResolvedClass<int>();
+      ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:140:9: Error: Couldn't find constructor 'ResolvedClass'.
+  const resolved_prefix.ResolvedClass<int>();
+        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:141:25: Error: Couldn't find constructor 'ResolvedClass'.
+  resolved_prefix. /**/ ResolvedClass<int>();
+                        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:142:7: Error: Couldn't find constructor 'ResolvedClass'.
+  new resolved_prefix.ResolvedClass /**/ <int>();
+      ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:143:9: Error: Couldn't find constructor 'ResolvedClass'.
+  const resolved_prefix.ResolvedClass<int> /**/ ();
+        ^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:145:19: Error: Couldn't find constructor 'UnresolvedClass'.
+  resolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+                  ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:146:23: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+                      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:147:25: Error: Couldn't find constructor 'UnresolvedClass'.
+  const resolved_prefix.UnresolvedClass<int>.unresolvedConstructor();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:148:25: Error: Couldn't find constructor 'UnresolvedClass'.
+  resolved_prefix /**/ .UnresolvedClass<int>.unresolvedConstructor();
+                        ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:149:23: Error: Couldn't find constructor 'UnresolvedClass'.
+  new resolved_prefix.UnresolvedClass<int> /**/ .unresolvedConstructor();
+                      ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:151:14: Error: Couldn't find constructor 'UnresolvedClass'.
+      . /**/ UnresolvedClass<int>. /**/ unresolvedConstructor();
+             ^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:153:38: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  resolved_prefix.ResolvedClass<int>.unresolvedConstructor();
+                                     ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:154:42: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new resolved_prefix.ResolvedClass<int>.unresolvedConstructor();
+                                         ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:155:44: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const resolved_prefix.ResolvedClass<int>.unresolvedConstructor();
+                                           ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:156:44: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  resolved_prefix /**/ .ResolvedClass<int>.unresolvedConstructor();
+                                           ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:157:48: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  new resolved_prefix.ResolvedClass<int> /**/ .unresolvedConstructor();
+                                               ^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_constructor_invocation.dart:158:56: Error: Couldn't find constructor 'ResolvedClass.unresolvedConstructor'.
+  const resolved_prefix. /**/ ResolvedClass<int>. /**/ unresolvedConstructor();
+                                                       ^^^^^^^^^^^^^^^^^^^^^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/unresolved_prefix_access.dart.weak.modular.expect b/pkg/front_end/testcases/general/unresolved_prefix_access.dart.weak.modular.expect
new file mode 100644
index 0000000..a7f4e10
--- /dev/null
+++ b/pkg/front_end/testcases/general/unresolved_prefix_access.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/unresolved_prefix_access.dart:8:10: Error: Method not found: 'unresolved'.
+//   prefix.unresolved();
+//          ^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/unresolved_prefix_access.dart:9:3: Error: A prefix can't be used with null-aware operators.
+// Try replacing '?.' with '.'
+//   prefix?.test();
+//   ^^^^^^
+//
+import self as self;
+
+import "org-dartlang-testcase:///unresolved_prefix_access.dart" as prefix;
+
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/unresolved_prefix_access.dart:8:10: Error: Method not found: 'unresolved'.
+  prefix.unresolved();
+         ^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/unresolved_prefix_access.dart:9:3: Error: A prefix can't be used with null-aware operators.
+Try replacing '?.' with '.'
+  prefix?.test();
+  ^^^^^^" in self::test();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/unsound_promotion.dart.weak.modular.expect b/pkg/front_end/testcases/general/unsound_promotion.dart.weak.modular.expect
new file mode 100644
index 0000000..e5a07f2
--- /dev/null
+++ b/pkg/front_end/testcases/general/unsound_promotion.dart.weak.modular.expect
@@ -0,0 +1,72 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/unsound_promotion.dart:21:16: Error: Inferred type argument 'S' doesn't conform to the bound 'A' of the type variable 'T' on 'g'.
+//  - 'A' is from 'pkg/front_end/testcases/general/unsound_promotion.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     var list = g(s);
+//                ^
+// pkg/front_end/testcases/general/unsound_promotion.dart:13:11: Context: This is the type variable whose bound isn't conformed to.
+// List<T> g<T extends A>(T t) {
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B implements self::A {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+static field core::List<self::A*>* list;
+static method g<T extends self::A*>(self::g::T* t) → core::List<self::g::T*>* {
+  self::list = <self::g::T*>[];
+  core::print(self::list.{core::Object::runtimeType}{core::Type*});
+  return self::list as{TypeError} core::List<self::g::T*>*;
+}
+static method f<S extends core::Object* = dynamic>(self::f::S* s) → core::List<self::f::S*>* {
+  if(s is self::A*) {
+    core::List<self::f::S*>* list = self::g<self::f::S*>(s{self::f::S* & self::A* /* '*' & '*' = '*' */});
+    return list;
+  }
+  return null;
+}
+static method main() → dynamic {
+  self::f<self::B*>(new self::C::•());
+  core::print(self::list.{core::Object::runtimeType}{core::Type*});
+  core::List<self::A*>* aList;
+  aList = self::list;
+  core::Object* o = aList;
+  aList = o as{TypeError} core::List<self::A*>*;
+}
diff --git a/pkg/front_end/testcases/general/unused_methods.dart.weak.modular.expect b/pkg/front_end/testcases/general/unused_methods.dart.weak.modular.expect
new file mode 100644
index 0000000..060120a
--- /dev/null
+++ b/pkg/front_end/testcases/general/unused_methods.dart.weak.modular.expect
@@ -0,0 +1,126 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class UnusedClass extends core::Object {
+  constructor •() → self::UnusedClass*
+    : super core::Object::•() {
+    core::print("Unused");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class UsedAsBaseClass extends core::Object {
+  synthetic constructor •() → self::UsedAsBaseClass*
+    : super core::Object::•()
+    ;
+  method usedInSubclass() → void {
+    core::print("Unused");
+  }
+  method calledFromB() → void {
+    this.{self::UsedAsBaseClass::calledFromSubclass}(){() →* void};
+  }
+  method calledFromSubclass() → void {
+    core::print("Unused");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class UsedAsInterface extends core::Object {
+  synthetic constructor •() → self::UsedAsInterface*
+    : super core::Object::•()
+    ;
+  method usedInSubclass() → void {
+    core::print("Unused");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class InstantiatedButMethodsUnused extends core::Object {
+  synthetic constructor •() → self::InstantiatedButMethodsUnused*
+    : super core::Object::•()
+    ;
+  method usedInSubclass() → void {
+    core::print("Unused");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class ClassA extends self::UsedAsBaseClass implements self::UsedAsInterface, self::InstantiatedButMethodsUnused {
+  synthetic constructor •() → self::ClassA*
+    : super self::UsedAsBaseClass::•()
+    ;
+  method usedInSubclass() → void {
+    core::print("A");
+  }
+}
+class ClassB extends self::UsedAsBaseClass implements self::UsedAsInterface, self::InstantiatedButMethodsUnused {
+  synthetic constructor •() → self::ClassB*
+    : super self::UsedAsBaseClass::•()
+    ;
+  method usedInSubclass() → void {
+    core::print("B");
+    this.{self::UsedAsBaseClass::calledFromB}(){() →* void};
+  }
+  method calledFromSubclass() → void {}
+}
+static method baseClassCall(self::UsedAsBaseClass* object) → void {
+  object.{self::UsedAsBaseClass::usedInSubclass}(){() →* void};
+}
+static method interfaceCall(self::UsedAsInterface* object) → void {
+  object.{self::UsedAsInterface::usedInSubclass}(){() →* void};
+}
+static method exactCallA(self::ClassA* object) → void {
+  object.{self::ClassA::usedInSubclass}(){() →* void};
+}
+static method exactCallB(self::ClassB* object) → void {
+  object.{self::ClassB::usedInSubclass}(){() →* void};
+}
+static method unusedTopLevel() → dynamic {
+  core::print("Unused");
+}
+static method usedTopLevel() → dynamic {}
+static method main() → dynamic {
+  self::usedTopLevel();
+  self::ClassA* a = new self::ClassA::•();
+  self::exactCallA(a);
+  self::baseClassCall(a);
+  self::interfaceCall(a);
+  self::ClassB* b = new self::ClassB::•();
+  self::exactCallB(b);
+  self::baseClassCall(b);
+  self::interfaceCall(b);
+  new self::InstantiatedButMethodsUnused::•();
+}
diff --git a/pkg/front_end/testcases/general/var_as_type_name.dart.weak.modular.expect b/pkg/front_end/testcases/general/var_as_type_name.dart.weak.modular.expect
new file mode 100644
index 0000000..4673e3d
--- /dev/null
+++ b/pkg/front_end/testcases/general/var_as_type_name.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/var_as_type_name.dart:6:15: Error: The keyword 'var' can't be used as a type name.
+//   Map<String, var> m;
+//               ^^^
+//
+// pkg/front_end/testcases/general/var_as_type_name.dart:6:15: Error: Type 'var' not found.
+//   Map<String, var> m;
+//               ^^^
+//
+// pkg/front_end/testcases/general/var_as_type_name.dart:6:15: Error: 'var' isn't a type.
+//   Map<String, var> m;
+//               ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::Map<core::String*, invalid-type>* m = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::A* a = new self::A::•();
+  a.{self::A::m} = null;
+}
diff --git a/pkg/front_end/testcases/general/vm_type_ops.dart.weak.modular.expect b/pkg/front_end/testcases/general/vm_type_ops.dart.weak.modular.expect
new file mode 100644
index 0000000..47d6412f
--- /dev/null
+++ b/pkg/front_end/testcases/general/vm_type_ops.dart.weak.modular.expect
@@ -0,0 +1,127 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A<core::String*> {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C<T1 extends core::Object* = dynamic, T2 extends core::Object* = dynamic, T3 extends core::Object* = dynamic> extends self::B {
+  synthetic constructor •() → self::C<self::C::T1*, self::C::T2*, self::C::T3*>*
+    : super self::B::•()
+    ;
+}
+class D<P extends core::Object* = dynamic, Q extends core::Object* = dynamic> extends self::C<core::int*, self::D::Q*, self::D::P*> {
+  covariant-by-class field core::Map<self::D::P*, self::D::Q*>* foo;
+  constructor •(dynamic tt) → self::D<self::D::P*, self::D::Q*>*
+    : self::D::foo = tt as{TypeError,ForDynamic} core::Map<self::D::P*, self::D::Q*>*, super self::C::•()
+    ;
+  method foo2(dynamic y) → dynamic {
+    if(y is self::A<self::D::P*>*) {
+      core::print("21");
+    }
+    if(y is self::C<dynamic, self::D::Q*, core::List<self::D::P*>*>*) {
+      core::print("22");
+    }
+    this.{self::D::foo} = y as{TypeError,ForDynamic} core::Map<self::D::P*, self::D::Q*>*;
+  }
+  method foo3<T1 extends core::Object* = dynamic, T2 extends core::Object* = dynamic>(dynamic z) → dynamic {
+    if(z is self::A<self::D::foo3::T1*>*) {
+      core::print("31");
+    }
+    if(z is self::C<core::Map<self::D::foo3::T1*, self::D::P*>*, core::List<self::D::foo3::T2*>*, self::D::Q*>*) {
+      core::print("32");
+    }
+    return (z as core::Map<self::D::foo3::T2*, self::D::Q*>*).{core::Map::values}{core::Iterable<self::D::Q*>*};
+  }
+  method foo4(dynamic w) → core::Map<self::D::P*, self::D::Q*>* {
+    core::List<core::Map<self::D::P*, self::D::Q*>*>* list = <core::Map<self::D::P*, self::D::Q*>*>[w as{TypeError,ForDynamic} core::Map<self::D::P*, self::D::Q*>*];
+    return w as{TypeError,ForDynamic} core::Map<self::D::P*, self::D::Q*>*;
+  }
+}
+class E<P extends core::String*> extends core::Object {
+  static factory •<P extends core::String*>() → self::E<self::E::•::P*>*
+    return null;
+  method foo6<covariant-by-class T extends self::E::P*, U extends core::List<self::E::foo6::T*>* = core::List<self::E::P*>*>(core::Map<self::E::foo6::T*, self::E::foo6::U*>* map) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class F<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::F<self::F::T*>*
+    : super core::Object::•()
+    ;
+  abstract method foo7<covariant-by-class Q extends self::F::T*>(self::F::foo7::Q* a, covariant-by-declaration core::num* b, covariant-by-class self::F::T* c) → void;
+  abstract method foo8<covariant-by-class Q extends self::F::T*>(self::F::foo8::Q* a, covariant-by-declaration core::num* b, covariant-by-class self::F::T* c) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class G<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::G<self::G::T*>*
+    : super core::Object::•()
+    ;
+  method foo7<covariant-by-class Q extends self::G::T*>(self::G::foo7::Q* a, core::int* b, covariant-by-class self::G::T* c) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class H<T extends core::Object* = dynamic> extends self::G<self::H::T*> implements self::F<self::H::T*> {
+  synthetic constructor •() → self::H<self::H::T*>*
+    : super self::G::•()
+    ;
+  method foo8<covariant-by-class Q extends self::H::T*>(self::H::foo8::Q* a, covariant-by-declaration core::int* b, covariant-by-class self::H::T* c) → void {}
+  forwarding-stub method foo7<covariant-by-class Q extends self::H::T*>(self::H::foo7::Q* a, covariant-by-declaration core::num* b, covariant-by-class self::H::T* c) → void
+    return super.{self::G::foo7}<self::H::foo7::Q*>(a, b as core::int*, c);
+}
+static field core::List<core::Iterable<dynamic>*>* globalVar;
+static method foo1(dynamic x) → dynamic {
+  if(x is self::B*) {
+    core::print("11");
+  }
+  if(x is self::C<core::int*, core::Object*, dynamic>*) {
+    core::print("12");
+  }
+  return x as self::A<core::int*>*;
+}
+static method foo5(dynamic x) → void {
+  self::globalVar = x as{TypeError,ForDynamic} core::List<core::Iterable<dynamic>*>*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/void_methods.dart.weak.modular.expect b/pkg/front_end/testcases/general/void_methods.dart.weak.modular.expect
new file mode 100644
index 0000000..dff46ae
--- /dev/null
+++ b/pkg/front_end/testcases/general/void_methods.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  field core::List<dynamic>* list = <dynamic>[1, 2, 3];
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  set first(dynamic x) → void
+    return let final core::List<dynamic>* #t1 = this.{self::Foo::list}{core::List<dynamic>*} in let final core::int* #t2 = 0 in let final dynamic #t3 = x in let final void #t4 = #t1.{core::List::[]=}(#t2, #t3){(core::int*, dynamic) →* void} in #t3;
+  operator []=(dynamic x, dynamic y) → void
+    return let final core::List<dynamic>* #t5 = this.{self::Foo::list}{core::List<dynamic>*} in let final dynamic #t6 = x as{TypeError,ForDynamic} core::int* in let final dynamic #t7 = y in let final void #t8 = #t5.{core::List::[]=}(#t6, #t7){(core::int*, dynamic) →* void} in #t7;
+  method clear() → void
+    return this.{self::Foo::list}{core::List<dynamic>*}.{core::List::clear}(){() →* void};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::Foo::•().{self::Foo::first} = 4;
+  new self::Foo::•().{self::Foo::[]=}(3, 4){(dynamic, dynamic) →* void};
+  new self::Foo::•().{self::Foo::clear}(){() →* void};
+}
diff --git a/pkg/front_end/testcases/general/warn_unresolved_sends.dart.weak.modular.expect b/pkg/front_end/testcases/general/warn_unresolved_sends.dart.weak.modular.expect
new file mode 100644
index 0000000..300333f2
--- /dev/null
+++ b/pkg/front_end/testcases/general/warn_unresolved_sends.dart.weak.modular.expect
@@ -0,0 +1,136 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/warn_unresolved_sends.dart:48:10: Error: The getter 'missingField' isn't defined for the class 'D'.
+//  - 'D' is from 'pkg/front_end/testcases/general/warn_unresolved_sends.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'missingField'.
+//     this.missingField;
+//          ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/warn_unresolved_sends.dart:49:10: Error: The setter 'missingField' isn't defined for the class 'D'.
+//  - 'D' is from 'pkg/front_end/testcases/general/warn_unresolved_sends.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'missingField'.
+//     this.missingField = 0;
+//          ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/warn_unresolved_sends.dart:50:10: Error: The method 'missingMethod' isn't defined for the class 'D'.
+//  - 'D' is from 'pkg/front_end/testcases/general/warn_unresolved_sends.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'missingMethod'.
+//     this.missingMethod();
+//          ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/warn_unresolved_sends.dart:52:5: Error: The getter 'missingField' isn't defined for the class 'D'.
+//  - 'D' is from 'pkg/front_end/testcases/general/warn_unresolved_sends.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'missingField'.
+//     missingField;
+//     ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/warn_unresolved_sends.dart:53:5: Error: The setter 'missingField' isn't defined for the class 'D'.
+//  - 'D' is from 'pkg/front_end/testcases/general/warn_unresolved_sends.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'missingField'.
+//     missingField = 0;
+//     ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/general/warn_unresolved_sends.dart:54:5: Error: The method 'missingMethod' isn't defined for the class 'D'.
+//  - 'D' is from 'pkg/front_end/testcases/general/warn_unresolved_sends.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'missingMethod'.
+//     missingMethod();
+//     ^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field dynamic superField = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method superMethod() → dynamic {}
+  get setterOnly() → dynamic
+    return null;
+  set setterOnly(dynamic _) → void {}
+  get getterOnly() → dynamic
+    return null;
+  set getterOnly(dynamic _) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  field dynamic field = null;
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  set setterOnly(dynamic _) → void {}
+  get getterOnly() → dynamic
+    return null;
+  method method() → dynamic {}
+  method test() → void {
+    this.{self::D::field}{dynamic};
+    this.{self::C::superField}{dynamic};
+    this.{self::D::field} = 0;
+    this.{self::C::superField} = 0;
+    this.{self::D::method}(){() →* dynamic};
+    this.{self::C::superMethod}(){() →* dynamic};
+    this.{self::C::setterOnly}{dynamic};
+    this.{self::D::setterOnly} = 0;
+    this.{self::D::getterOnly}{dynamic};
+    this.{self::C::getterOnly} = 0;
+    this.{self::D::field}{dynamic};
+    this.{self::C::superField}{dynamic};
+    this.{self::D::field} = 0;
+    this.{self::C::superField} = 0;
+    this.{self::D::method}(){() →* dynamic};
+    this.{self::C::superMethod}(){() →* dynamic};
+    this.{self::C::setterOnly}{dynamic};
+    this.{self::D::setterOnly} = 0;
+    this.{self::D::getterOnly}{dynamic};
+    this.{self::C::getterOnly} = 0;
+    invalid-expression "pkg/front_end/testcases/general/warn_unresolved_sends.dart:48:10: Error: The getter 'missingField' isn't defined for the class 'D'.
+ - 'D' is from 'pkg/front_end/testcases/general/warn_unresolved_sends.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'missingField'.
+    this.missingField;
+         ^^^^^^^^^^^^" in this{<unresolved>}.missingField;
+    invalid-expression "pkg/front_end/testcases/general/warn_unresolved_sends.dart:49:10: Error: The setter 'missingField' isn't defined for the class 'D'.
+ - 'D' is from 'pkg/front_end/testcases/general/warn_unresolved_sends.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'missingField'.
+    this.missingField = 0;
+         ^^^^^^^^^^^^" in this{<unresolved>}.missingField = 0;
+    invalid-expression "pkg/front_end/testcases/general/warn_unresolved_sends.dart:50:10: Error: The method 'missingMethod' isn't defined for the class 'D'.
+ - 'D' is from 'pkg/front_end/testcases/general/warn_unresolved_sends.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'missingMethod'.
+    this.missingMethod();
+         ^^^^^^^^^^^^^" in this{<unresolved>}.missingMethod();
+    invalid-expression "pkg/front_end/testcases/general/warn_unresolved_sends.dart:52:5: Error: The getter 'missingField' isn't defined for the class 'D'.
+ - 'D' is from 'pkg/front_end/testcases/general/warn_unresolved_sends.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'missingField'.
+    missingField;
+    ^^^^^^^^^^^^" in this{<unresolved>}.missingField;
+    invalid-expression "pkg/front_end/testcases/general/warn_unresolved_sends.dart:53:5: Error: The setter 'missingField' isn't defined for the class 'D'.
+ - 'D' is from 'pkg/front_end/testcases/general/warn_unresolved_sends.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'missingField'.
+    missingField = 0;
+    ^^^^^^^^^^^^" in this{<unresolved>}.missingField = 0;
+    invalid-expression "pkg/front_end/testcases/general/warn_unresolved_sends.dart:54:5: Error: The method 'missingMethod' isn't defined for the class 'D'.
+ - 'D' is from 'pkg/front_end/testcases/general/warn_unresolved_sends.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'missingMethod'.
+    missingMethod();
+    ^^^^^^^^^^^^^" in this{<unresolved>}.missingMethod();
+  }
+}
+class E extends self::D {
+  field dynamic missingField = null;
+  synthetic constructor •() → self::E*
+    : super self::D::•()
+    ;
+  method missingMethod() → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart.weak.modular.expect b/pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart.weak.modular.expect
new file mode 100644
index 0000000..a688b79
--- /dev/null
+++ b/pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart.weak.modular.expect
@@ -0,0 +1,116 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart:8:10: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+//   A<num> fieldOfA; // Error.
+//          ^
+// pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart:9:17: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+//   static A<num> staticFieldOfA; // Error.
+//                 ^
+// pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart:12:13: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+// extension E<X extends A<num>> // Error.
+//             ^
+// pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart:14:17: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+//   static A<num> fieldOfE; // Error.
+//                 ^
+// pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart:15:16: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'A' in the return type.
+// Try changing type arguments so that they conform to the bounds.
+//   A<num> fooOfE() => null; // Error.
+//                ^
+// pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart:16:22: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+//   void barOfE(A<num> a) {} // Error.
+//                      ^
+// pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart:17:15: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+//   void bazOfE<Y extends A<num>>() {} // Error.
+//               ^
+// pkg/front_end/testcases/general/well_boundness_checks_in_outline.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends int> {}
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::int*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  field self::A<core::num*>* fieldOfA = null;
+  static field self::A<core::num*>* staticFieldOfA = null;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension E<X extends self::A<core::num*>*> on self::A<core::int*>* {
+  static field fieldOfE = self::E|fieldOfE;
+  method fooOfE = self::E|fooOfE;
+  tearoff fooOfE = self::E|get#fooOfE;
+  method barOfE = self::E|barOfE;
+  tearoff barOfE = self::E|get#barOfE;
+  method bazOfE = self::E|bazOfE;
+  tearoff bazOfE = self::E|get#bazOfE;
+}
+static field self::A<core::num*>* E|fieldOfE;
+static method E|fooOfE<X extends self::A<core::num*>*>(lowered final self::A<core::int*>* #this) → self::A<core::num*>*
+  return null;
+static method E|get#fooOfE<X extends self::A<core::num*>*>(lowered final self::A<core::int*>* #this) → () →* self::A<core::num*>*
+  return () → self::A<core::num*>* => self::E|fooOfE<self::E|get#fooOfE::X*>(#this);
+static method E|barOfE<X extends self::A<core::num*>*>(lowered final self::A<core::int*>* #this, self::A<core::num*>* a) → void {}
+static method E|get#barOfE<X extends self::A<core::num*>*>(lowered final self::A<core::int*>* #this) → (self::A<core::num*>*) →* void
+  return (self::A<core::num*>* a) → void => self::E|barOfE<self::E|get#barOfE::X*>(#this, a);
+static method E|bazOfE<X extends self::A<core::num*>*, Y extends self::A<core::num*>*>(lowered final self::A<core::int*>* #this) → void {}
+static method E|get#bazOfE<X extends self::A<core::num*>*>(lowered final self::A<core::int*>* #this) → <Y extends self::A<core::num*>*>() →* void
+  return <Y extends self::A<core::num*>*>() → void => self::E|bazOfE<self::E|get#bazOfE::X*, Y*>(#this);
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/with_dependencies/abstract_members_from_dill/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/with_dependencies/abstract_members_from_dill/main.dart.weak.modular.expect
new file mode 100644
index 0000000..f1e3ba3
--- /dev/null
+++ b/pkg/front_end/testcases/general/with_dependencies/abstract_members_from_dill/main.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library;
+import self as self;
+import "main_lib.dart" as mai;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+class B extends mai::A {
+  synthetic constructor •() → self::B*
+    : super mai::A::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/with_dependencies/extension_from_dill/extension_from_dill.dart.weak.modular.expect b/pkg/front_end/testcases/general/with_dependencies/extension_from_dill/extension_from_dill.dart.weak.modular.expect
new file mode 100644
index 0000000..85f323d
--- /dev/null
+++ b/pkg/front_end/testcases/general/with_dependencies/extension_from_dill/extension_from_dill.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library;
+import self as self;
+import "extension_from_dill_lib2.dart" as ext;
+
+import "org-dartlang-testcase:///extension_from_dill_lib.dart";
+
+static method main() → dynamic {
+  ext::Extension|foo("");
+}
diff --git a/pkg/front_end/testcases/general/with_dependencies/issue43538/main.dart.weak.modular.expect b/pkg/front_end/testcases/general/with_dependencies/issue43538/main.dart.weak.modular.expect
new file mode 100644
index 0000000..c6ae209
--- /dev/null
+++ b/pkg/front_end/testcases/general/with_dependencies/issue43538/main.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library;
+import self as self;
+import "const_lib.dart" as con;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///const_lib.dart";
+
+static const field con::B* crossModule = #C3;
+static method main() → dynamic {
+  self::expect(2.71, #C3.{con::A::d}{core::double*});
+  self::expect("default", #C3.{con::A::s}{core::String*});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = 2.71
+  #C2 = "default"
+  #C3 = con::B {d:#C1, s:#C2}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///main.dart:
+- B. (from org-dartlang-testcase:///const_lib.dart:16:9)
+- _B&A&M. (from org-dartlang-testcase:///const_lib.dart:15:7)
+- A. (from org-dartlang-testcase:///const_lib.dart:6:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/general/with_dependencies/issue_43084/issue_43084.dart.weak.modular.expect b/pkg/front_end/testcases/general/with_dependencies/issue_43084/issue_43084.dart.weak.modular.expect
new file mode 100644
index 0000000..d7417c6
--- /dev/null
+++ b/pkg/front_end/testcases/general/with_dependencies/issue_43084/issue_43084.dart.weak.modular.expect
@@ -0,0 +1,19 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/with_dependencies/issue_43084/issue_43084.dart:8:20: Error: Couldn't find constructor 'Bar'.
+//   Bar<int> x = new Bar<int>();
+//                    ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue_43084_lib.dart";
+
+static method main() → dynamic {
+  invalid-type x = invalid-expression "pkg/front_end/testcases/general/with_dependencies/issue_43084/issue_43084.dart:8:20: Error: Couldn't find constructor 'Bar'.
+  Bar<int> x = new Bar<int>();
+                   ^^^";
+  core::print(x);
+}
diff --git a/pkg/front_end/testcases/general/with_dependencies/issue_43084_2/issue_43084.dart.weak.modular.expect b/pkg/front_end/testcases/general/with_dependencies/issue_43084_2/issue_43084.dart.weak.modular.expect
new file mode 100644
index 0000000..1854736
--- /dev/null
+++ b/pkg/front_end/testcases/general/with_dependencies/issue_43084_2/issue_43084.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/with_dependencies/issue_43084_2/issue_43084.dart:8:3: Error: Couldn't find constructor 'F'.
+//   F();
+//   ^
+//
+import self as self;
+
+import "org-dartlang-testcase:///issue_43084_lib.dart";
+
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/with_dependencies/issue_43084_2/issue_43084.dart:8:3: Error: Couldn't find constructor 'F'.
+  F();
+  ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/with_dependencies/mixin_from_dill/mixin_from_dill.dart.weak.modular.expect b/pkg/front_end/testcases/general/with_dependencies/mixin_from_dill/mixin_from_dill.dart.weak.modular.expect
new file mode 100644
index 0000000..fc924c0
--- /dev/null
+++ b/pkg/front_end/testcases/general/with_dependencies/mixin_from_dill/mixin_from_dill.dart.weak.modular.expect
@@ -0,0 +1,99 @@
+library;
+import self as self;
+import "mixin_from_dill_lib1.dart" as mix;
+import "dart:core" as core;
+import "mixin_from_dill_lib2.dart" as mix2;
+
+import "org-dartlang-testcase:///mixin_from_dill_lib1.dart" as lib1;
+import "org-dartlang-testcase:///mixin_from_dill_lib2.dart" as lib2;
+
+static method main() → dynamic {
+  mix::Foo* foo1 = new mix::Foo::•();
+  if(foo1 == null)
+    throw "what?";
+  if(!(foo1 =={mix::_Foo&B&D::==}{(dynamic) →* core::bool*} foo1))
+    throw "what?";
+  foo1.{mix::_Foo&B&D::x}(){() →* void};
+  mix2::Foo* foo2 = new mix2::Foo::•();
+  if(foo2 == null)
+    throw "what?";
+  if(!(foo2 =={mix2::_Foo&B&D::==}{(dynamic) →* core::bool*} foo2))
+    throw "what?";
+  foo2.{mix2::_Foo&B&D::x}(){() →* void};
+}
+
+library;
+import self as mix2;
+import "dart:core" as core;
+
+abstract class _Foo&B&D = mix2::B with mix2::D /*isAnonymousMixin*/  {
+  synthetic constructor •() → mix2::_Foo&B&D*
+    : super mix2::B::•()
+    ;
+  mixin-super-stub operator ==(dynamic dynamic) → core::bool*
+    return super.{mix2::D::==}(dynamic);
+  mixin-super-stub method x() → void
+    return super.{mix2::D::x}();
+}
+class Foo extends mix2::_Foo&B&D {
+  synthetic constructor •() → mix2::Foo*
+    : super mix2::_Foo&B&D::•()
+    ;
+}
+abstract class B extends core::Object implements mix2::C {
+  synthetic constructor •() → mix2::B*
+    : super core::Object::•()
+    ;
+  operator ==(dynamic dynamic) → core::bool* {
+    core::print("B.==");
+    return true;
+  }
+  method x() → void {
+    core::print("B.x");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object {
+  synthetic constructor •() → mix2::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D extends core::Object implements mix2::C {
+  synthetic constructor •() → mix2::D*
+    : super core::Object::•()
+    ;
+  operator ==(dynamic dynamic) → core::bool* {
+    core::print("D.==");
+    return true;
+  }
+  method x() → void {
+    core::print("D.x");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/general/with_dependencies/mixin_from_dill/mixin_from_dill.no_link.dart.weak.modular.expect b/pkg/front_end/testcases/general/with_dependencies/mixin_from_dill/mixin_from_dill.no_link.dart.weak.modular.expect
new file mode 100644
index 0000000..787fde3
--- /dev/null
+++ b/pkg/front_end/testcases/general/with_dependencies/mixin_from_dill/mixin_from_dill.no_link.dart.weak.modular.expect
@@ -0,0 +1,175 @@
+library;
+import self as self;
+import "mixin_from_dill_lib1.dart" as mix;
+import "dart:core" as core;
+import "mixin_from_dill_lib2.dart" as mix2;
+
+import "org-dartlang-testcase:///mixin_from_dill_lib1.dart" as lib1;
+import "org-dartlang-testcase:///mixin_from_dill_lib2.dart" as lib2;
+
+static method main() → dynamic {
+  mix::Foo* foo1 = new mix::Foo::•();
+  if(foo1 == null)
+    throw "what?";
+  if(!(foo1 =={mix::_Foo&B&D::==}{(dynamic) →* core::bool*} foo1))
+    throw "what?";
+  foo1.{mix::_Foo&B&D::x}(){() →* void};
+  mix2::Foo* foo2 = new mix2::Foo::•();
+  if(foo2 == null)
+    throw "what?";
+  if(!(foo2 =={mix2::_Foo&B&D::==}{(dynamic) →* core::bool*} foo2))
+    throw "what?";
+  foo2.{mix2::_Foo&B&D::x}(){() →* void};
+}
+
+library;
+import self as mix;
+import "dart:core" as core;
+
+abstract class _Foo&B&D = mix::B with mix::D /*isAnonymousMixin*/  {
+  synthetic constructor •() → mix::_Foo&B&D*
+    : super mix::B::•()
+    ;
+  mixin-super-stub operator ==(dynamic dynamic) → core::bool*
+    return super.{mix::D::==}(dynamic);
+  mixin-super-stub method x() → void
+    return super.{mix::D::x}();
+}
+class Foo extends mix::_Foo&B&D {
+  synthetic constructor •() → mix::Foo*
+    : super mix::_Foo&B&D::•()
+    ;
+}
+abstract class B extends core::Object implements mix::C {
+  synthetic constructor •() → mix::B*
+    : super core::Object::•()
+    ;
+  operator ==(dynamic dynamic) → core::bool* {
+    core::print("B.==");
+    return true;
+  }
+  method x() → void {
+    core::print("B.x");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object {
+  synthetic constructor •() → mix::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D extends core::Object implements mix::C {
+  synthetic constructor •() → mix::D*
+    : super core::Object::•()
+    ;
+  operator ==(dynamic dynamic) → core::bool* {
+    core::print("D.==");
+    return true;
+  }
+  method x() → void {
+    core::print("D.x");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+library;
+import self as mix2;
+import "dart:core" as core;
+
+abstract class _Foo&B&D = mix2::B with mix2::D /*isAnonymousMixin*/  {
+  synthetic constructor •() → mix2::_Foo&B&D*
+    : super mix2::B::•()
+    ;
+  mixin-super-stub operator ==(dynamic dynamic) → core::bool*
+    return super.{mix2::D::==}(dynamic);
+  mixin-super-stub method x() → void
+    return super.{mix2::D::x}();
+}
+class Foo extends mix2::_Foo&B&D {
+  synthetic constructor •() → mix2::Foo*
+    : super mix2::_Foo&B&D::•()
+    ;
+}
+abstract class B extends core::Object implements mix2::C {
+  synthetic constructor •() → mix2::B*
+    : super core::Object::•()
+    ;
+  operator ==(dynamic dynamic) → core::bool* {
+    core::print("B.==");
+    return true;
+  }
+  method x() → void {
+    core::print("B.x");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object {
+  synthetic constructor •() → mix2::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D extends core::Object implements mix2::C {
+  synthetic constructor •() → mix2::D*
+    : super core::Object::•()
+    ;
+  operator ==(dynamic dynamic) → core::bool* {
+    core::print("D.==");
+    return true;
+  }
+  method x() → void {
+    core::print("D.x");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/general/with_dependencies/stub_or_not/stub_or_not.dart.weak.modular.expect b/pkg/front_end/testcases/general/with_dependencies/stub_or_not/stub_or_not.dart.weak.modular.expect
new file mode 100644
index 0000000..02192bf
--- /dev/null
+++ b/pkg/front_end/testcases/general/with_dependencies/stub_or_not/stub_or_not.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library;
+import self as self;
+import "stub_or_not_lib1.dart" as stu;
+
+import "org-dartlang-testcase:///stub_or_not_lib1.dart";
+
+class ProblemClass extends stu::Foo {
+  synthetic constructor •() → self::ProblemClass*
+    : super stu::Foo::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/general/with_dependencies/stub_or_not/stub_or_not.no_link.dart.weak.modular.expect b/pkg/front_end/testcases/general/with_dependencies/stub_or_not/stub_or_not.no_link.dart.weak.modular.expect
new file mode 100644
index 0000000..68cbb20
--- /dev/null
+++ b/pkg/front_end/testcases/general/with_dependencies/stub_or_not/stub_or_not.no_link.dart.weak.modular.expect
@@ -0,0 +1,89 @@
+library;
+import self as self;
+import "stub_or_not_lib1.dart" as stu;
+
+import "org-dartlang-testcase:///stub_or_not_lib1.dart";
+
+class ProblemClass extends stu::Foo {
+  synthetic constructor •() → self::ProblemClass*
+    : super stu::Foo::•()
+    ;
+}
+static method main() → dynamic {}
+
+library;
+import self as stu;
+import "dart:core" as core;
+import "stub_or_not_lib2.dart" as stu2;
+
+import "org-dartlang-testcase:///stub_or_not_lib2.dart";
+
+abstract class Qux extends core::Object implements stu2::EventFileA {
+  synthetic constructor •() → stu::Qux*
+    : super core::Object::•()
+    ;
+  method handleEvent(covariant-by-declaration stu2::EvenFileB* entry) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class EvenFileBPrime extends stu2::EvenFileB {
+  synthetic constructor •() → stu::EvenFileBPrime*
+    : super stu2::EvenFileB::•()
+    ;
+}
+abstract class Baz extends stu::Qux {
+  synthetic constructor •() → stu::Baz*
+    : super stu::Qux::•()
+    ;
+  method handleEvent(covariant-by-declaration stu::EvenFileBPrime* entry) → void {}
+}
+abstract class Foo extends stu::Baz implements stu::Qux {
+  synthetic constructor •() → stu::Foo*
+    : super stu::Baz::•()
+    ;
+  abstract member-signature method handleEvent(covariant-by-declaration stu2::EvenFileB* entry) → void; -> stu::Qux::handleEvent
+}
+
+library;
+import self as stu2;
+import "dart:core" as core;
+
+abstract class EventFileA extends core::Object {
+  synthetic constructor •() → stu2::EventFileA*
+    : super core::Object::•()
+    ;
+  abstract method handleEvent(stu2::EvenFileB* entry) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class EvenFileB extends core::Object {
+  synthetic constructor •() → stu2::EvenFileB*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/general/with_dependencies/variance_from_dill/variance_from_dill.dart.weak.modular.expect b/pkg/front_end/testcases/general/with_dependencies/variance_from_dill/variance_from_dill.dart.weak.modular.expect
new file mode 100644
index 0000000..18c9317
--- /dev/null
+++ b/pkg/front_end/testcases/general/with_dependencies/variance_from_dill/variance_from_dill.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///variance_from_dill_lib.dart";
+
+typedef G<unrelated T extends core::Object? = dynamic> = (() → dynamic) → dynamic;
+static method main() → dynamic {
+  core::print(#C1);
+}
+
+constants  {
+  #C1 = TypeLiteralConstant((() →* dynamic) →* dynamic)
+}
diff --git a/pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart.weak.modular.expect b/pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart.weak.modular.expect
new file mode 100644
index 0000000..5d340a4
--- /dev/null
+++ b/pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart:14:27: Error: Too few positional arguments: 1 required, 0 given.
+// typedef void G<@A<dynamic>() T>(T t);
+//                           ^
+// pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart:6:9: Context: Found this candidate, but the arguments don't match.
+//   const A(o);
+//         ^
+//
+// pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart:16:24: Error: Too few positional arguments: 1 required, 0 given.
+// void method1<@A<String>() T>(T t) {}
+//                        ^
+// pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart:6:9: Context: Found this candidate, but the arguments don't match.
+//   const A(o);
+//         ^
+//
+// pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart:9:22: Error: Too few positional arguments: 1 required, 0 given.
+// void Function<@A<int>() T>(T)? f;
+//                      ^
+// pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart:6:9: Context: Found this candidate, but the arguments don't match.
+//   const A(o);
+//         ^
+//
+// pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart:18:35: Error: Too few positional arguments: 1 required, 0 given.
+// void method2(void Function<@A<num>() T>(T) f) {}
+//                                   ^
+// pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart:6:9: Context: Found this candidate, but the arguments don't match.
+//   const A(o);
+//         ^
+//
+// pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart:24:24: Error: Too few positional arguments: 1 required, 0 given.
+//   void local<@A<double>() T>(T t) {}
+//                        ^
+// pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart:6:9: Context: Found this candidate, but the arguments don't match.
+//   const A(o);
+//         ^
+//
+// pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart:26:24: Error: Too few positional arguments: 1 required, 0 given.
+//   void Function<@A<int>() T>(T)? f;
+//                        ^
+// pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart:6:9: Context: Found this candidate, but the arguments don't match.
+//   const A(o);
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F = <T extends core::Object? = dynamic>(T%) → void;
+typedef G<@invalid-expression "pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart:14:27: Error: Too few positional arguments: 1 required, 0 given.
+typedef void G<@A<dynamic>() T>(T t);
+                          ^" contravariant T extends core::Object? = dynamic> = (T%) → void;
+class A<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const constructor •(dynamic o) → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+}
+class Class<T extends <S extends core::Object? = dynamic>(S%) → void> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::T>
+    : super core::Object::•()
+    ;
+}
+static field <T extends core::Object? = dynamic>(T%) →? void f;
+static method method1<@invalid-expression "pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart:16:24: Error: Too few positional arguments: 1 required, 0 given.
+void method1<@A<String>() T>(T t) {}
+                       ^" T extends core::Object? = dynamic>(self::method1::T% t) → void {}
+static method method2(<T extends core::Object? = dynamic>(T%) → void f) → void {}
+static method main() → dynamic {
+  function local<@invalid-expression "pkg/front_end/testcases/generic_metadata/erroneous_function_type_parameter.dart:24:24: Error: Too few positional arguments: 1 required, 0 given.
+  void local<@A<double>() T>(T t) {}
+                       ^" T extends core::Object? = dynamic>(T% t) → void {}
+  <T extends core::Object? = dynamic>(T%) →? void f;
+}
diff --git a/pkg/front_end/testcases/generic_metadata/from_dill/main.dart.weak.modular.expect b/pkg/front_end/testcases/generic_metadata/from_dill/main.dart.weak.modular.expect
new file mode 100644
index 0000000..6900388
--- /dev/null
+++ b/pkg/front_end/testcases/generic_metadata/from_dill/main.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "main_lib.dart" as mai;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+static method main() → dynamic {
+  mai::C1<<T extends core::Object? = dynamic>(T%) → T%> c1 = new mai::C1::•<<T extends core::Object? = dynamic>(T%) → T%>();
+  mai::C1<<T extends core::Object? = dynamic>(T%) → T%> c2 = new mai::C1::•<<T extends core::Object? = dynamic>(T%) → T%>();
+  mai::C2<<T extends core::Object? = dynamic>() → void> c3 = new mai::C2::•<<T extends core::Object? = dynamic>() → void>();
+  mai::C2<<T extends core::Object? = dynamic>() → void> c4 = new mai::C2::•<<int extends core::Object? = dynamic>() → void>();
+  mai::C3<<T extends core::Object? = dynamic>() → T%> c5 = new mai::C3::•<<T extends core::Object? = dynamic>() → T%>();
+  mai::C3<<T extends core::Object? = dynamic>() → T%> c6 = new mai::C3::•<<T extends core::Object? = dynamic>() → T%>();
+  mai::C4<<T extends core::Object? = dynamic>(T%) → void> c7 = new mai::C4::•<<T extends core::Object? = dynamic>(T%) → void>();
+  mai::C4<<T extends core::Object? = dynamic>(T%) → void> c8 = new mai::C4::•<<T extends core::Object? = dynamic>(T%) → void>();
+  mai::C5<<T extends <S extends core::Object? = dynamic>(S%) → S% = dynamic>(T) → T> c9 = new mai::C5::•<<T extends <S extends core::Object? = dynamic>(S%) → S% = dynamic>(T) → T>();
+  mai::C5<<T extends <S extends core::Object? = dynamic>(S%) → S% = dynamic>(T) → T> c10 = new mai::C5::•<<T extends <S extends core::Object? = dynamic>(S%) → S%>(T) → T>();
+  mai::C6<<T extends core::Object? = dynamic, S extends core::Object? = dynamic>(T%, S%, <V extends S% = dynamic, U extends core::Object? = dynamic>(T%, U%, V%, core::Map<S%, U%>) → V%) → T%> c11 = new mai::C6::•<<T extends core::Object? = dynamic, S extends core::Object? = dynamic>(T%, S%, <V extends S% = dynamic, U extends core::Object? = dynamic>(T%, U%, V%, core::Map<S%, U%>) → V%) → T%>();
+  mai::C6<<T extends core::Object? = dynamic, S extends core::Object? = dynamic>(T%, S%, <V extends S% = dynamic, U extends core::Object? = dynamic>(T%, U%, V%, core::Map<S%, U%>) → V%) → T%> c12 = new mai::C6::•<<T extends core::Object? = dynamic, S extends core::Object? = dynamic>(T%, S%, <V extends S%, U extends core::Object? = dynamic>(T%, U%, V%, core::Map<S%, U%>) → V%) → T%>();
+}
diff --git a/pkg/front_end/testcases/generic_metadata/function_type_parameter.dart.weak.modular.expect b/pkg/front_end/testcases/generic_metadata/function_type_parameter.dart.weak.modular.expect
new file mode 100644
index 0000000..d081a19
--- /dev/null
+++ b/pkg/front_end/testcases/generic_metadata/function_type_parameter.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef F = <T extends core::Object? = dynamic>(T%) → void;
+typedef G<@#C1 contravariant T extends core::Object? = dynamic> = (T%) → void;
+class A<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+}
+class Class<T extends <S extends core::Object? = dynamic>(S%) → void> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::T>
+    : super core::Object::•()
+    ;
+}
+static field <T extends core::Object? = dynamic>(T%) →? void f;
+static method method1<@#C2 T extends core::Object? = dynamic>(self::method1::T% t) → void {}
+static method method2(<T extends core::Object? = dynamic>(T%) → void f) → void {}
+static method main() → dynamic {
+  function local<@#C3 T extends core::Object? = dynamic>(T% t) → void {}
+  <T extends core::Object? = dynamic>(T%) →? void f;
+}
+
+constants  {
+  #C1 = self::A<dynamic> {}
+  #C2 = self::A<core::String*> {}
+  #C3 = self::A<core::double*> {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///function_type_parameter.dart:
+- A. (from org-dartlang-testcase:///function_type_parameter.dart:6:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/generic_metadata/generic_metadata.dart.weak.modular.expect b/pkg/front_end/testcases/generic_metadata/generic_metadata.dart.weak.modular.expect
new file mode 100644
index 0000000..b60d2ce
--- /dev/null
+++ b/pkg/front_end/testcases/generic_metadata/generic_metadata.dart.weak.modular.expect
@@ -0,0 +1,99 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/generic_metadata/generic_metadata.dart:21:2: Error: Expected 1 type arguments.
+// @A<int, num>() // error
+//  ^
+// pkg/front_end/testcases/generic_metadata/generic_metadata.dart:6:9: Context: Found this candidate, but the arguments don't match.
+//   const A();
+//         ^
+//
+// pkg/front_end/testcases/generic_metadata/generic_metadata.dart:22:2: Error: Expected 2 type arguments.
+// @B<int>() // error
+//  ^
+// pkg/front_end/testcases/generic_metadata/generic_metadata.dart:10:9: Context: Found this candidate, but the arguments don't match.
+//   const B();
+//         ^
+//
+// pkg/front_end/testcases/generic_metadata/generic_metadata.dart:23:2: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'T' on 'C'.
+// Try changing type arguments so that they conform to the bounds.
+// @C<String>() // error
+//  ^
+// pkg/front_end/testcases/generic_metadata/generic_metadata.dart:13:9: Context: This is the type variable whose bound isn't conformed to.
+// class C<T extends num> {
+//         ^
+//
+// pkg/front_end/testcases/generic_metadata/generic_metadata.dart:24:2: Error: Type argument 'num' doesn't conform to the bound 'S' of the type variable 'T' on 'D'.
+// Try changing type arguments so that they conform to the bounds.
+// @D<int, num>() // error
+//  ^
+// pkg/front_end/testcases/generic_metadata/generic_metadata.dart:17:24: Context: This is the type variable whose bound isn't conformed to.
+// class D<S extends num, T extends S> {
+//                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+}
+class B<S extends core::Object? = dynamic, T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::B<self::B::S%, self::B::T%>
+    : super core::Object::•()
+    ;
+}
+class C<T extends core::num> extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::C<self::C::T>
+    : super core::Object::•()
+    ;
+}
+class D<S extends core::num, T extends self::D::S = core::num> extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::D<self::D::S, self::D::T>
+    : super core::Object::•()
+    ;
+}
+@invalid-expression "pkg/front_end/testcases/generic_metadata/generic_metadata.dart:21:2: Error: Expected 1 type arguments.
+@A<int, num>() // error
+ ^"
+@invalid-expression "pkg/front_end/testcases/generic_metadata/generic_metadata.dart:22:2: Error: Expected 2 type arguments.
+@B<int>() // error
+ ^"
+@#C1
+@#C2
+static method test() → dynamic {}
+@#C3
+@#C4
+@#C5
+@#C6
+@#C7
+@#C7
+@#C8
+@#C9
+@#C9
+@#C10
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::C<core::String*> {}
+  #C2 = self::D<core::int*, core::num*> {}
+  #C3 = self::A<dynamic> {}
+  #C4 = self::A<core::int*> {}
+  #C5 = self::B<dynamic, dynamic> {}
+  #C6 = self::B<core::int*, core::String*> {}
+  #C7 = self::C<core::num*> {}
+  #C8 = self::C<core::int*> {}
+  #C9 = self::D<core::num*, core::num*> {}
+  #C10 = self::D<core::num*, core::int*> {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///generic_metadata.dart:
+- C. (from org-dartlang-testcase:///generic_metadata.dart:14:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- D. (from org-dartlang-testcase:///generic_metadata.dart:18:9)
+- A. (from org-dartlang-testcase:///generic_metadata.dart:6:9)
+- B. (from org-dartlang-testcase:///generic_metadata.dart:10:9)
diff --git a/pkg/front_end/testcases/generic_metadata/inferred_generic_types_in_arguments_and_bounds.dart.weak.modular.expect b/pkg/front_end/testcases/generic_metadata/inferred_generic_types_in_arguments_and_bounds.dart.weak.modular.expect
new file mode 100644
index 0000000..86bb196
--- /dev/null
+++ b/pkg/front_end/testcases/generic_metadata/inferred_generic_types_in_arguments_and_bounds.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+class A<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+}
+static method foo<Y extends core::Object? = dynamic>(self::foo::Y% y) → self::A<self::foo::Y%>
+  return throw 42;
+static method test() → dynamic {
+  self::A<<Z extends core::Object? = dynamic>(dynamic) → Never> x = self::foo<<Z extends core::Object? = dynamic>(dynamic) → Never>(<Z extends core::Object? = dynamic>(dynamic Z) → Never => throw 42);
+  core::List<<Y extends core::Object? = dynamic>(Y%) → self::A<Y%>> y = <<Y extends core::Object? = dynamic>(Y%) → self::A<Y%>>[#C1];
+  core::Set<<Y extends core::Object? = dynamic>(Y%) → self::A<Y%>> z = block {
+    final core::Set<<Y extends core::Object? = dynamic>(Y%) → self::A<Y%>> #t1 = col::LinkedHashSet::•<<Y extends core::Object? = dynamic>(Y%) → self::A<Y%>>();
+    #t1.{core::Set::add}{Invariant}(y.{core::Iterable::first}{<Y extends core::Object? = dynamic>(Y%) → self::A<Y%>}){(<Y extends core::Object? = dynamic>(Y%) → self::A<Y%>) → core::bool};
+  } =>#t1;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::foo
+}
diff --git a/pkg/front_end/testcases/generic_metadata/issue45329.dart.weak.modular.expect b/pkg/front_end/testcases/generic_metadata/issue45329.dart.weak.modular.expect
new file mode 100644
index 0000000..3dbf472
--- /dev/null
+++ b/pkg/front_end/testcases/generic_metadata/issue45329.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/generic_metadata/issue45329.dart:6:9: Error: Expected an identifier, but got 'void'.
+// Try inserting an identifier before 'void'.
+//   local<void Function()>() {}
+//         ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test() → dynamic {
+  function local<#T1 extends core::Object? = dynamic>() → Null {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/generic_metadata/issue45330.dart.weak.modular.expect b/pkg/front_end/testcases/generic_metadata/issue45330.dart.weak.modular.expect
new file mode 100644
index 0000000..156f3fb
--- /dev/null
+++ b/pkg/front_end/testcases/generic_metadata/issue45330.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/generic_metadata/issue45330.dart:10:31: Error: Type 'T' is a bound of itself via 'T'.
+// Try breaking the cycle by removing at least on of the 'extends' clauses in the cycle.
+//   genericMethod<void Function<T extends T>()>();
+//                               ^
+//
+// pkg/front_end/testcases/generic_metadata/issue45330_lib.dart:35:31: Error: Type 'T' is a bound of itself via 'T'.
+// Try breaking the cycle by removing at least on of the 'extends' clauses in the cycle.
+//   genericMethod<void Function<T extends T>()>();
+//                               ^
+//
+import self as self;
+import "dart:core" as core;
+
+part issue45330_lib.dart;
+static method genericMethod<T extends core::Object? = dynamic>() → void {}
+static method testInMain() → dynamic {
+  self::genericMethod<<T extends invalid-type>() → void>();
+}
+static method main() → dynamic {}
+static method /* from org-dartlang-testcase:///issue45330_lib.dart */ testInPart() → dynamic {
+  self::genericMethod<<T extends invalid-type>() → void>();
+}
diff --git a/pkg/front_end/testcases/generic_metadata/nested_generic_arguments_and_bounds.dart.weak.modular.expect b/pkg/front_end/testcases/generic_metadata/nested_generic_arguments_and_bounds.dart.weak.modular.expect
new file mode 100644
index 0000000..5c86a64
--- /dev/null
+++ b/pkg/front_end/testcases/generic_metadata/nested_generic_arguments_and_bounds.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef F<invariant U extends core::Object? = dynamic> = <V extends U% = dynamic>(V%) → dynamic;
+class A<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+}
+static method foo() → self::A<<Y extends <Z extends core::Object? = dynamic>(Z%) → dynamic = dynamic>(Y) → dynamic>
+  return throw 42;
+static method bar() → self::A<<V extends <W extends core::Object? = dynamic>(W%) → dynamic = dynamic>(V) → dynamic>
+  return throw 42;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/generic_metadata/simple_generic_types_in_arguments_and_bounds.dart.weak.modular.expect b/pkg/front_end/testcases/generic_metadata/simple_generic_types_in_arguments_and_bounds.dart.weak.modular.expect
new file mode 100644
index 0000000..3c45ce6
--- /dev/null
+++ b/pkg/front_end/testcases/generic_metadata/simple_generic_types_in_arguments_and_bounds.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+}
+class B extends self::A<<Y extends core::Object? = dynamic>(Y%) → dynamic> {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+}
+class C<Z extends <Y extends core::Object? = dynamic>(Y%) → dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::Z>
+    : super core::Object::•()
+    ;
+}
+static method foo(self::A<<Y extends core::Object? = dynamic>(Y%) → dynamic> x) → self::A<<Y extends core::Object? = dynamic>(Y%) → dynamic>
+  return throw 42;
+static method bar<V extends <Y extends core::Object? = dynamic>(Y%) → dynamic>() → dynamic
+  return throw 42;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/generic_metadata/type_parameters_in_default_types.dart.weak.modular.expect b/pkg/front_end/testcases/generic_metadata/type_parameters_in_default_types.dart.weak.modular.expect
new file mode 100644
index 0000000..f970a2a
--- /dev/null
+++ b/pkg/front_end/testcases/generic_metadata/type_parameters_in_default_types.dart.weak.modular.expect
@@ -0,0 +1,5 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+
+static method foo<X extends <Y extends self::foo::X = dynamic>() → dynamic = <Y extends dynamic>() → dynamic>() → dynamic {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/generic_metadata/typedef_generic_types_in_arguments_and_bounds.dart.weak.modular.expect b/pkg/front_end/testcases/generic_metadata/typedef_generic_types_in_arguments_and_bounds.dart.weak.modular.expect
new file mode 100644
index 0000000..e853954
--- /dev/null
+++ b/pkg/front_end/testcases/generic_metadata/typedef_generic_types_in_arguments_and_bounds.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef F = <Y extends core::Object? = dynamic>(Y%) → dynamic;
+class A<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+}
+class B extends self::A<<Y extends core::Object? = dynamic>(Y%) → dynamic> {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+}
+class C<Z extends <Y extends core::Object? = dynamic>(Y%) → dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::Z>
+    : super core::Object::•()
+    ;
+}
+static method foo(self::A<<Y extends core::Object? = dynamic>(Y%) → dynamic> x) → self::A<<Y extends core::Object? = dynamic>(Y%) → dynamic>
+  return throw 42;
+static method bar<V extends <Y extends core::Object? = dynamic>(Y%) → dynamic>() → dynamic
+  return throw 42;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/implicit_getter_calls/getter_call.dart.weak.modular.expect b/pkg/front_end/testcases/implicit_getter_calls/getter_call.dart.weak.modular.expect
new file mode 100644
index 0000000..90a2cad
--- /dev/null
+++ b/pkg/front_end/testcases/implicit_getter_calls/getter_call.dart.weak.modular.expect
@@ -0,0 +1,187 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::Function* field1a = #C1;
+  field () →* core::int* field1b = #C1;
+  field (core::int*) →* core::int* field2 = #C2;
+  field (core::int*, core::int*) →* core::int* field3 = #C3;
+  field (core::int*, [core::int*]) →* core::int* field4 = #C4;
+  field ([core::int*, core::int*]) →* core::int* field5 = #C5;
+  field (core::int*, {b: core::int*}) →* core::int* field6 = #C6;
+  field ({a: core::int*, b: core::int*}) →* core::int* field7 = #C7;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  get getter1a() → core::Function*
+    return #C1;
+  get getter1b() → () →* core::int*
+    return #C1;
+  get getter2() → (core::int*) →* core::int*
+    return #C2;
+  get getter3() → (core::int*, core::int*) →* core::int*
+    return #C3;
+  get getter4() → (core::int*, [core::int*]) →* core::int*
+    return #C4;
+  get getter5() → ([core::int*, core::int*]) →* core::int*
+    return #C5;
+  get getter6() → (core::int*, {b: core::int*}) →* core::int*
+    return #C6;
+  get getter7() → ({a: core::int*, b: core::int*}) →* core::int*
+    return #C7;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Subclass extends self::Class {
+  synthetic constructor •() → self::Subclass*
+    : super self::Class::•()
+    ;
+  get field1a() → core::Function* {
+    self::enableRead = false;
+    return #C1;
+  }
+  get field1b() → () →* core::int* {
+    self::enableRead = false;
+    return #C1;
+  }
+  get field2() → (core::int*) →* core::int* {
+    self::enableRead = false;
+    return #C2;
+  }
+  get field3() → (core::int*, core::int*) →* core::int* {
+    self::enableRead = false;
+    return #C3;
+  }
+  get field4() → (core::int*, [core::int*]) →* core::int* {
+    self::enableRead = false;
+    return #C4;
+  }
+  get field5() → ([core::int*, core::int*]) →* core::int* {
+    self::enableRead = false;
+    return #C5;
+  }
+  get field6() → (core::int*, {b: core::int*}) →* core::int* {
+    self::enableRead = false;
+    return #C6;
+  }
+  get field7() → ({a: core::int*, b: core::int*}) →* core::int* {
+    self::enableRead = false;
+    return #C7;
+  }
+  get getter1a() → core::Function* {
+    self::enableRead = false;
+    return #C1;
+  }
+  get getter1b() → () →* core::int* {
+    self::enableRead = false;
+    return #C1;
+  }
+  get getter2() → (core::int*) →* core::int* {
+    self::enableRead = false;
+    return #C2;
+  }
+  get getter3() → (core::int*, core::int*) →* core::int* {
+    self::enableRead = false;
+    return #C3;
+  }
+  get getter4() → (core::int*, [core::int*]) →* core::int* {
+    self::enableRead = false;
+    return #C4;
+  }
+  get getter5() → ([core::int*, core::int*]) →* core::int* {
+    self::enableRead = false;
+    return #C5;
+  }
+  get getter6() → (core::int*, {b: core::int*}) →* core::int* {
+    self::enableRead = false;
+    return #C6;
+  }
+  get getter7() → ({a: core::int*, b: core::int*}) →* core::int* {
+    self::enableRead = false;
+    return #C7;
+  }
+}
+static field core::bool* enableRead = true;
+static method read(core::int* value) → core::int*
+  return self::enableRead ?{core::int*} value : 1.{core::int::unary-}(){() →* core::int*};
+static method method1() → core::int*
+  return 0;
+static method method2(core::int* a) → core::int*
+  return a.{core::int::unary-}(){() →* core::int*};
+static method method3(core::int* a, core::int* b) → core::int*
+  return a.{core::num::-}(b){(core::num*) →* core::int*};
+static method method4(core::int* a, [core::int* b = #C8]) → core::int*
+  return a.{core::num::-}(b){(core::num*) →* core::int*};
+static method method5([core::int* a = #C8, core::int* b = #C8]) → core::int*
+  return a.{core::num::-}(b){(core::num*) →* core::int*};
+static method method6(core::int* a, {core::int* b = #C8}) → core::int*
+  return a.{core::num::-}(b){(core::num*) →* core::int*};
+static method method7({core::int* a = #C8, core::int* b = #C8}) → core::int*
+  return a.{core::num::-}(b){(core::num*) →* core::int*};
+static method main() → dynamic {
+  self::callField(new self::Class::•());
+  self::callGetter(new self::Class::•());
+  self::callField(new self::Subclass::•());
+  self::callGetter(new self::Subclass::•());
+}
+static method callField(self::Class* c) → dynamic {
+  self::expect(0, c.{self::Class::field1a}());
+  self::expect(0, c.{self::Class::field1b}(){() →* core::int*});
+  self::expect(42.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t1 = c in let final core::int* #t2 = self::read(42) in #t1.{self::Class::field2}(#t2){(core::int*) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t3 = c in let final core::int* #t4 = self::read(12) in let final core::int* #t5 = self::read(23) in #t3.{self::Class::field3}(#t4, #t5){(core::int*, core::int*) →* core::int*});
+  self::expect(12, let final self::Class* #t6 = c in let final core::int* #t7 = self::read(12) in #t6.{self::Class::field4}(#t7){(core::int*, [core::int*]) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t8 = c in let final core::int* #t9 = self::read(12) in let final core::int* #t10 = self::read(23) in #t8.{self::Class::field4}(#t9, #t10){(core::int*, [core::int*]) →* core::int*});
+  self::expect(0, c.{self::Class::field5}(){([core::int*, core::int*]) →* core::int*});
+  self::expect(12, let final self::Class* #t11 = c in let final core::int* #t12 = self::read(12) in #t11.{self::Class::field5}(#t12){([core::int*, core::int*]) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t13 = c in let final core::int* #t14 = self::read(12) in let final core::int* #t15 = self::read(23) in #t13.{self::Class::field5}(#t14, #t15){([core::int*, core::int*]) →* core::int*});
+  self::expect(12, let final self::Class* #t16 = c in let final core::int* #t17 = self::read(12) in #t16.{self::Class::field6}(#t17){(core::int*, {b: core::int*}) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t18 = c in let final core::int* #t19 = self::read(12) in let final core::int* #t20 = self::read(23) in #t18.{self::Class::field6}(#t19, b: #t20){(core::int*, {b: core::int*}) →* core::int*});
+  self::expect(0, c.{self::Class::field7}(){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(12, let final self::Class* #t21 = c in let final core::int* #t22 = self::read(12) in #t21.{self::Class::field7}(a: #t22){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(23.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t23 = c in let final core::int* #t24 = self::read(23) in #t23.{self::Class::field7}(b: #t24){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t25 = c in let final core::int* #t26 = self::read(12) in let final core::int* #t27 = self::read(23) in #t25.{self::Class::field7}(a: #t26, b: #t27){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t28 = c in let final core::int* #t29 = self::read(23) in let final core::int* #t30 = self::read(12) in #t28.{self::Class::field7}(b: #t29, a: #t30){({a: core::int*, b: core::int*}) →* core::int*});
+}
+static method callGetter(self::Class* c) → dynamic {
+  self::expect(0, c.{self::Class::getter1a}());
+  self::expect(0, c.{self::Class::getter1b}(){() →* core::int*});
+  self::expect(42.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t31 = c in let final core::int* #t32 = self::read(42) in #t31.{self::Class::getter2}(#t32){(core::int*) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t33 = c in let final core::int* #t34 = self::read(12) in let final core::int* #t35 = self::read(23) in #t33.{self::Class::getter3}(#t34, #t35){(core::int*, core::int*) →* core::int*});
+  self::expect(12, let final self::Class* #t36 = c in let final core::int* #t37 = self::read(12) in #t36.{self::Class::getter4}(#t37){(core::int*, [core::int*]) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t38 = c in let final core::int* #t39 = self::read(12) in let final core::int* #t40 = self::read(23) in #t38.{self::Class::getter4}(#t39, #t40){(core::int*, [core::int*]) →* core::int*});
+  self::expect(0, c.{self::Class::getter5}(){([core::int*, core::int*]) →* core::int*});
+  self::expect(12, let final self::Class* #t41 = c in let final core::int* #t42 = self::read(12) in #t41.{self::Class::getter5}(#t42){([core::int*, core::int*]) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t43 = c in let final core::int* #t44 = self::read(12) in let final core::int* #t45 = self::read(23) in #t43.{self::Class::getter5}(#t44, #t45){([core::int*, core::int*]) →* core::int*});
+  self::expect(12, let final self::Class* #t46 = c in let final core::int* #t47 = self::read(12) in #t46.{self::Class::getter6}(#t47){(core::int*, {b: core::int*}) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t48 = c in let final core::int* #t49 = self::read(12) in let final core::int* #t50 = self::read(23) in #t48.{self::Class::getter6}(#t49, b: #t50){(core::int*, {b: core::int*}) →* core::int*});
+  self::expect(0, c.{self::Class::getter7}(){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(12, let final self::Class* #t51 = c in let final core::int* #t52 = self::read(12) in #t51.{self::Class::getter7}(a: #t52){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(23.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t53 = c in let final core::int* #t54 = self::read(23) in #t53.{self::Class::getter7}(b: #t54){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t55 = c in let final core::int* #t56 = self::read(12) in let final core::int* #t57 = self::read(23) in #t55.{self::Class::getter7}(a: #t56, b: #t57){({a: core::int*, b: core::int*}) →* core::int*});
+  self::expect(11.{core::int::unary-}(){() →* core::int*}, let final self::Class* #t58 = c in let final core::int* #t59 = self::read(23) in let final core::int* #t60 = self::read(12) in #t58.{self::Class::getter7}(b: #t59, a: #t60){({a: core::int*, b: core::int*}) →* core::int*});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  self::enableRead = true;
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, ${actual}";
+}
+
+constants  {
+  #C1 = static-tearoff self::method1
+  #C2 = static-tearoff self::method2
+  #C3 = static-tearoff self::method3
+  #C4 = static-tearoff self::method4
+  #C5 = static-tearoff self::method5
+  #C6 = static-tearoff self::method6
+  #C7 = static-tearoff self::method7
+  #C8 = 0
+}
diff --git a/pkg/front_end/testcases/implicit_getter_calls/this_field_call.dart.weak.modular.expect b/pkg/front_end/testcases/implicit_getter_calls/this_field_call.dart.weak.modular.expect
new file mode 100644
index 0000000..c46c847
--- /dev/null
+++ b/pkg/front_end/testcases/implicit_getter_calls/this_field_call.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  field (self::A::T*) →* void f;
+  constructor •((self::A::T*) →* void f) → self::A<self::A::T*>*
+    : self::A::f = f, super core::Object::•()
+    ;
+  method foo(covariant-by-class self::A::T* x) → dynamic
+    return let final self::A::T* #t1 = x in this.{self::A::f}(#t1){(self::A::T*) →* void};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::A::•<core::int*>((core::int* x) → Null {}).{self::A::foo}(3){(core::int*) →* dynamic};
+}
diff --git a/pkg/front_end/testcases/incremental/change_main.yaml b/pkg/front_end/testcases/incremental/change_main.yaml
new file mode 100644
index 0000000..e7167fa
--- /dev/null
+++ b/pkg/front_end/testcases/incremental/change_main.yaml
@@ -0,0 +1,59 @@
+# Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+# for details. All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE.md file.
+
+# Change entry point between deltas, provoking the read of the new entry
+# point before the read of the previous entry point. This triggers the crash
+# in https://github.com/flutter/flutter/issues/95014
+
+type: newworld
+worlds:
+  - entry: first.dart
+    experiments: alternative-invalidation-strategy
+    sources:
+      first.dart: |
+        import 'second.dart';
+
+        main() {
+          method1();
+          method2();
+        }
+        method1() {}
+      second.dart: |
+        import 'first.dart';
+
+        main() {
+          method1();
+          method2();
+        }
+        method2() {}
+    expectedLibraryCount: 2
+  - entry: second.dart
+    experiments: alternative-invalidation-strategy
+    worldType: updated
+    expectInitializeFromDill: false
+    invalidate:
+      [second.dart, first.dart]
+    sources:
+      first.dart: |
+        import 'second.dart';
+
+        main() {
+          method1();
+          method2();
+        }
+        method1() {
+          print('method1');
+        }
+      second.dart: |
+        import 'first.dart';
+
+        main() {
+          method1();
+          method2();
+        }
+        method2() {
+          print('method2');
+        }
+    expectedLibraryCount: 2
+    expectsRebuildBodiesOnly: true
diff --git a/pkg/front_end/testcases/incremental/change_main.yaml.world.1.expect b/pkg/front_end/testcases/incremental/change_main.yaml.world.1.expect
new file mode 100644
index 0000000..1e283df
--- /dev/null
+++ b/pkg/front_end/testcases/incremental/change_main.yaml.world.1.expect
@@ -0,0 +1,21 @@
+main = fir::main;
+library from "org-dartlang-test:///first.dart" as fir {
+
+  import "org-dartlang-test:///second.dart";
+
+  static method main() → dynamic {
+    fir::method1();
+    sec::method2();
+  }
+  static method method1() → dynamic {}
+}
+library from "org-dartlang-test:///second.dart" as sec {
+
+  import "org-dartlang-test:///first.dart";
+
+  static method main() → dynamic {
+    fir::method1();
+    sec::method2();
+  }
+  static method method2() → dynamic {}
+}
diff --git a/pkg/front_end/testcases/incremental/change_main.yaml.world.2.expect b/pkg/front_end/testcases/incremental/change_main.yaml.world.2.expect
new file mode 100644
index 0000000..df10188
--- /dev/null
+++ b/pkg/front_end/testcases/incremental/change_main.yaml.world.2.expect
@@ -0,0 +1,25 @@
+main = sec::main;
+library from "org-dartlang-test:///first.dart" as fir {
+
+  import "org-dartlang-test:///second.dart";
+
+  static method main() → dynamic {
+    fir::method1();
+    sec::method2();
+  }
+  static method method1() → dynamic {
+    dart.core::print("method1");
+  }
+}
+library from "org-dartlang-test:///second.dart" as sec {
+
+  import "org-dartlang-test:///first.dart";
+
+  static method main() → dynamic {
+    fir::method1();
+    sec::method2();
+  }
+  static method method2() → dynamic {
+    dart.core::print("method2");
+  }
+}
diff --git a/pkg/front_end/testcases/incremental/change_main2.yaml b/pkg/front_end/testcases/incremental/change_main2.yaml
new file mode 100644
index 0000000..1ceabb1
--- /dev/null
+++ b/pkg/front_end/testcases/incremental/change_main2.yaml
@@ -0,0 +1,45 @@
+# Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+# for details. All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE.md file.
+
+type: newworld
+worlds:
+  - entry: first.dart
+    experiments: alternative-invalidation-strategy
+    sources:
+      first.dart: |
+        import 'second.dart';
+
+        main() {
+          method1();
+          method2();
+        }
+        method1() {}
+      second.dart: |
+        import 'first.dart';
+
+        main() {
+          method1();
+          method2();
+        }
+        method2() {}
+    expectedLibraryCount: 2
+  - entry: second.dart
+    experiments: alternative-invalidation-strategy
+    worldType: updated
+    expectInitializeFromDill: false
+    invalidate:
+      - second.dart
+    sources:
+      second.dart: |
+        import 'first.dart';
+
+        main() {
+          method1();
+          method2();
+        }
+        method2() {
+          print('method2');
+        }
+    expectedLibraryCount: 2
+    expectsRebuildBodiesOnly: true
diff --git a/pkg/front_end/testcases/incremental/change_main2.yaml.world.1.expect b/pkg/front_end/testcases/incremental/change_main2.yaml.world.1.expect
new file mode 100644
index 0000000..1e283df
--- /dev/null
+++ b/pkg/front_end/testcases/incremental/change_main2.yaml.world.1.expect
@@ -0,0 +1,21 @@
+main = fir::main;
+library from "org-dartlang-test:///first.dart" as fir {
+
+  import "org-dartlang-test:///second.dart";
+
+  static method main() → dynamic {
+    fir::method1();
+    sec::method2();
+  }
+  static method method1() → dynamic {}
+}
+library from "org-dartlang-test:///second.dart" as sec {
+
+  import "org-dartlang-test:///first.dart";
+
+  static method main() → dynamic {
+    fir::method1();
+    sec::method2();
+  }
+  static method method2() → dynamic {}
+}
diff --git a/pkg/front_end/testcases/incremental/change_main2.yaml.world.2.expect b/pkg/front_end/testcases/incremental/change_main2.yaml.world.2.expect
new file mode 100644
index 0000000..d55656f
--- /dev/null
+++ b/pkg/front_end/testcases/incremental/change_main2.yaml.world.2.expect
@@ -0,0 +1,23 @@
+main = sec::main;
+library from "org-dartlang-test:///first.dart" as fir {
+
+  import "org-dartlang-test:///second.dart";
+
+  static method main() → dynamic {
+    fir::method1();
+    sec::method2();
+  }
+  static method method1() → dynamic {}
+}
+library from "org-dartlang-test:///second.dart" as sec {
+
+  import "org-dartlang-test:///first.dart";
+
+  static method main() → dynamic {
+    fir::method1();
+    sec::method2();
+  }
+  static method method2() → dynamic {
+    dart.core::print("method2");
+  }
+}
diff --git a/pkg/front_end/testcases/incremental/no_outline_change_50_ffi.yaml.world.1.expect b/pkg/front_end/testcases/incremental/no_outline_change_50_ffi.yaml.world.1.expect
index 4e4f764..ffb841a 100644
--- a/pkg/front_end/testcases/incremental/no_outline_change_50_ffi.yaml.world.1.expect
+++ b/pkg/front_end/testcases/incremental/no_outline_change_50_ffi.yaml.world.1.expect
@@ -40,6 +40,10 @@
   ffi::sizeOf,
   ffi::Dart_NativeMessageHandler,
   ffi::Abi,
+  ffi::AbiSpecificInteger,
+  ffi::AbiSpecificIntegerArray,
+  ffi::AbiSpecificIntegerMapping,
+  ffi::AbiSpecificIntegerPointer,
   ffi::Allocator,
   ffi::AllocatorAlloc,
   ffi::Array,
@@ -114,6 +118,10 @@
   ffi::sizeOf,
   ffi::Dart_NativeMessageHandler,
   ffi::Abi,
+  ffi::AbiSpecificInteger,
+  ffi::AbiSpecificIntegerArray,
+  ffi::AbiSpecificIntegerMapping,
+  ffi::AbiSpecificIntegerPointer,
   ffi::Allocator,
   ffi::AllocatorAlloc,
   ffi::Array,
diff --git a/pkg/front_end/testcases/incremental/no_outline_change_50_ffi.yaml.world.2.expect b/pkg/front_end/testcases/incremental/no_outline_change_50_ffi.yaml.world.2.expect
index ead3ad4..40804c4 100644
--- a/pkg/front_end/testcases/incremental/no_outline_change_50_ffi.yaml.world.2.expect
+++ b/pkg/front_end/testcases/incremental/no_outline_change_50_ffi.yaml.world.2.expect
@@ -40,6 +40,10 @@
   ffi::sizeOf,
   ffi::Dart_NativeMessageHandler,
   ffi::Abi,
+  ffi::AbiSpecificInteger,
+  ffi::AbiSpecificIntegerArray,
+  ffi::AbiSpecificIntegerMapping,
+  ffi::AbiSpecificIntegerPointer,
   ffi::Allocator,
   ffi::AllocatorAlloc,
   ffi::Array,
@@ -114,6 +118,10 @@
   ffi::sizeOf,
   ffi::Dart_NativeMessageHandler,
   ffi::Abi,
+  ffi::AbiSpecificInteger,
+  ffi::AbiSpecificIntegerArray,
+  ffi::AbiSpecificIntegerMapping,
+  ffi::AbiSpecificIntegerPointer,
   ffi::Allocator,
   ffi::AllocatorAlloc,
   ffi::Array,
diff --git a/pkg/front_end/testcases/incremental/part_main.yaml b/pkg/front_end/testcases/incremental/part_main.yaml
new file mode 100644
index 0000000..fc73d0d
--- /dev/null
+++ b/pkg/front_end/testcases/incremental/part_main.yaml
@@ -0,0 +1,53 @@
+# Copyright (c) 2019, the Dart project authors. Please see the AUTHORS file
+# for details. All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE.md file.
+
+# Compile an application, change a file, but don't change the outline.
+
+type: newworld
+worlds:
+  - entry: first.dart
+    experiments: alternative-invalidation-strategy
+    sources:
+      first.dart: |
+        library first;
+
+        part 'second.dart';
+
+        main() {
+          method1();
+          method2();
+        }
+        method1() {}
+      second.dart: |
+        part of first;
+
+        method2() {}
+    expectedLibraryCount: 1
+  - entry: first.dart
+    experiments: alternative-invalidation-strategy
+    worldType: updated
+    expectInitializeFromDill: false
+    invalidate:
+      [second.dart, first.dart]
+    sources:
+      first.dart: |
+        library first;
+
+        part 'second.dart';
+
+        main() {
+          method1();
+          method2();
+        }
+        method1() {
+          print('method1');
+        }
+      second.dart: |
+        part of first;
+
+        method2() {
+          print('method2');
+        }
+    expectedLibraryCount: 1
+    expectsRebuildBodiesOnly: true
diff --git a/pkg/front_end/testcases/incremental/part_main.yaml.world.1.expect b/pkg/front_end/testcases/incremental/part_main.yaml.world.1.expect
new file mode 100644
index 0000000..547dc7c
--- /dev/null
+++ b/pkg/front_end/testcases/incremental/part_main.yaml.world.1.expect
@@ -0,0 +1,11 @@
+main = fir::main;
+library first from "org-dartlang-test:///first.dart" as fir {
+
+  part second.dart;
+  static method main() → dynamic {
+    fir::method1();
+    fir::method2();
+  }
+  static method method1() → dynamic {}
+  static method /* from org-dartlang-test:///second.dart */ method2() → dynamic {}
+}
diff --git a/pkg/front_end/testcases/incremental/part_main.yaml.world.2.expect b/pkg/front_end/testcases/incremental/part_main.yaml.world.2.expect
new file mode 100644
index 0000000..8cd5855
--- /dev/null
+++ b/pkg/front_end/testcases/incremental/part_main.yaml.world.2.expect
@@ -0,0 +1,15 @@
+main = fir::main;
+library first from "org-dartlang-test:///first.dart" as fir {
+
+  part second.dart;
+  static method main() → dynamic {
+    fir::method1();
+    fir::method2();
+  }
+  static method method1() → dynamic {
+    dart.core::print("method1");
+  }
+  static method /* from org-dartlang-test:///second.dart */ method2() → dynamic {
+    dart.core::print("method2");
+  }
+}
diff --git a/pkg/front_end/testcases/incremental/second_first.yaml b/pkg/front_end/testcases/incremental/second_first.yaml
new file mode 100644
index 0000000..80faceb
--- /dev/null
+++ b/pkg/front_end/testcases/incremental/second_first.yaml
@@ -0,0 +1,43 @@
+# Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+# for details. All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE.md file.
+
+type: newworld
+worlds:
+  - entry: first.dart
+    experiments: alternative-invalidation-strategy
+    sources:
+      first.dart: |
+        import 'second.dart';
+
+        main() {
+          method1();
+          method2();
+        }
+        method1() {}
+      second.dart: |
+        method2() {}
+    expectedLibraryCount: 2
+  - entry: first.dart
+    experiments: alternative-invalidation-strategy
+    worldType: updated
+    expectInitializeFromDill: false
+    invalidate:
+        [second.dart, first.dart]
+    sources:
+      first.dart: |
+        import 'second.dart';
+
+        main() {
+          method1();
+          method2();
+        }
+        method1() {
+          print('method1');
+        }
+      second.dart: |
+        method2() {
+          print('method2');
+        }
+    expectedLibraryCount: 2
+    expectsRebuildBodiesOnly: true
diff --git a/pkg/front_end/testcases/incremental/second_first.yaml.world.1.expect b/pkg/front_end/testcases/incremental/second_first.yaml.world.1.expect
new file mode 100644
index 0000000..b38f4b8
--- /dev/null
+++ b/pkg/front_end/testcases/incremental/second_first.yaml.world.1.expect
@@ -0,0 +1,15 @@
+main = fir::main;
+library from "org-dartlang-test:///first.dart" as fir {
+
+  import "org-dartlang-test:///second.dart";
+
+  static method main() → dynamic {
+    fir::method1();
+    sec::method2();
+  }
+  static method method1() → dynamic {}
+}
+library from "org-dartlang-test:///second.dart" as sec {
+
+  static method method2() → dynamic {}
+}
diff --git a/pkg/front_end/testcases/incremental/second_first.yaml.world.2.expect b/pkg/front_end/testcases/incremental/second_first.yaml.world.2.expect
new file mode 100644
index 0000000..0b236b5
--- /dev/null
+++ b/pkg/front_end/testcases/incremental/second_first.yaml.world.2.expect
@@ -0,0 +1,19 @@
+main = fir::main;
+library from "org-dartlang-test:///first.dart" as fir {
+
+  import "org-dartlang-test:///second.dart";
+
+  static method main() → dynamic {
+    fir::method1();
+    sec::method2();
+  }
+  static method method1() → dynamic {
+    dart.core::print("method1");
+  }
+}
+library from "org-dartlang-test:///second.dart" as sec {
+
+  static method method2() → dynamic {
+    dart.core::print("method2");
+  }
+}
diff --git a/pkg/front_end/testcases/inference/abstract_class_instantiation.dart.weak.modular.expect b/pkg/front_end/testcases/inference/abstract_class_instantiation.dart.weak.modular.expect
new file mode 100644
index 0000000..e38191b
--- /dev/null
+++ b/pkg/front_end/testcases/inference/abstract_class_instantiation.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/abstract_class_instantiation.dart:15:34: Error: The class 'C' is abstract and can't be instantiated.
+//   var /*@type=dynamic */ x = new C();
+//                                  ^
+//
+// pkg/front_end/testcases/inference/abstract_class_instantiation.dart:16:34: Error: The class 'D' is abstract and can't be instantiated.
+//   var /*@type=dynamic */ y = new D(1);
+//                                  ^
+//
+// pkg/front_end/testcases/inference/abstract_class_instantiation.dart:17:24: Error: The class 'D' is abstract and can't be instantiated.
+//   D<List<int>> z = new D(/*@typeArgs=dynamic*/ []);
+//                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(self::D::T* t) → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → void {
+  dynamic x = throw new core::AbstractClassInstantiationError::•("C");
+  dynamic y = let final core::Object* #t1 = 1 in throw new core::AbstractClassInstantiationError::•("D");
+  self::D<core::List<core::int*>*>* z = let final core::Object* #t2 = <dynamic>[] in throw new core::AbstractClassInstantiationError::•("D");
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/assert.dart.weak.modular.expect b/pkg/front_end/testcases/inference/assert.dart.weak.modular.expect
new file mode 100644
index 0000000..1122765
--- /dev/null
+++ b/pkg/front_end/testcases/inference/assert.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method test() → void {
+  assert(self::f<core::bool*>());
+  assert(self::f<core::bool*>(), self::f<dynamic>());
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/assert_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/inference/assert_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..8d3a6de
--- /dev/null
+++ b/pkg/front_end/testcases/inference/assert_initializer.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  constructor expressionOnly() → self::C*
+    : assert(self::f<core::bool*>()), super core::Object::•()
+    ;
+  constructor expressionAndMessage() → self::C*
+    : assert(self::f<core::bool*>(), self::f<dynamic>()), super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {
+  assert(self::f<core::bool*>());
+  assert(self::f<core::bool*>(), self::f<dynamic>());
+}
diff --git a/pkg/front_end/testcases/inference/assign_local.dart.weak.modular.expect b/pkg/front_end/testcases/inference/assign_local.dart.weak.modular.expect
new file mode 100644
index 0000000..21f996a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/assign_local.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::Object* = dynamic> extends self::A<self::B::T*> {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super self::A::•()
+    ;
+}
+static method main() → dynamic {
+  core::num* x;
+  core::int* x1 = x = 1;
+  core::double* x2 = x = 1.0;
+  self::A<core::int*>* y;
+  self::A<core::int*>* y1 = y = new self::A::•<core::int*>();
+  self::B<core::int*>* y2 = y = new self::B::•<core::int*>();
+}
diff --git a/pkg/front_end/testcases/inference/async_await.dart.weak.modular.expect b/pkg/front_end/testcases/inference/async_await.dart.weak.modular.expect
new file mode 100644
index 0000000..3d172fc
--- /dev/null
+++ b/pkg/front_end/testcases/inference/async_await.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+abstract class MyFuture extends core::Object implements asy::Future<core::int*> {
+  synthetic constructor •() → self::MyFuture*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature method then<R extends core::Object* = dynamic>((core::int*) →* FutureOr<self::MyFuture::then::R*>* onValue, {core::Function* onError = #C1}) → asy::Future<self::MyFuture::then::R*>*; -> asy::Future::then
+  abstract member-signature method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<core::int*>*; -> asy::Future::catchError
+  abstract member-signature method whenComplete(() →* FutureOr<void>* action) → asy::Future<core::int*>*; -> asy::Future::whenComplete
+  abstract member-signature method asStream() → asy::Stream<core::int*>*; -> asy::Future::asStream
+  abstract member-signature method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<core::int*>* onTimeout = #C1}) → asy::Future<core::int*>*; -> asy::Future::timeout
+}
+static method test() → void async {
+  core::int* x0;
+  asy::Future<core::int*>* x1;
+  asy::Future<asy::Future<core::int*>*>* x2;
+  asy::Future<FutureOr<core::int*>*>* x3;
+  asy::Future<self::MyFuture*>* x4;
+  FutureOr<core::int*>* x5;
+  FutureOr<asy::Future<core::int*>*>* x6;
+  FutureOr<FutureOr<core::int*>*>* x7;
+  FutureOr<self::MyFuture*>* x8;
+  self::MyFuture* x9;
+  function test0() → asy::Future<core::int*>* async 
+    return x0;
+  function test1() → asy::Future<core::int*>* async 
+    return x1;
+  function test2() → asy::Future<asy::Future<core::int*>*>* async 
+    return x2;
+  function test3() → asy::Future<FutureOr<core::int*>*>* async 
+    return x3;
+  function test4() → asy::Future<self::MyFuture*>* async 
+    return x4;
+  function test5() → asy::Future<core::int*>* async 
+    return x5;
+  function test6() → asy::Future<asy::Future<core::int*>*>* async 
+    return x6;
+  function test7() → asy::Future<FutureOr<core::int*>*>* async 
+    return x7;
+  function test8() → asy::Future<self::MyFuture*>* async 
+    return x8;
+  function test9() → asy::Future<core::int*>* async 
+    return x9;
+  core::int* y0 = await x0;
+  core::int* y1 = await x1;
+  asy::Future<core::int*>* y2 = await x2;
+  FutureOr<core::int*>* y3 = await x3;
+  self::MyFuture* y4 = await x4;
+  core::int* y5 = await x5;
+  asy::Future<core::int*>* y6 = await x6;
+  FutureOr<core::int*>* y7 = await x7;
+  self::MyFuture* y8 = await x8;
+  core::int* y9 = await x9;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/inference/async_closure_return_type_flatten.dart.weak.modular.expect b/pkg/front_end/testcases/inference/async_closure_return_type_flatten.dart.weak.modular.expect
new file mode 100644
index 0000000..7974c45
--- /dev/null
+++ b/pkg/front_end/testcases/inference/async_closure_return_type_flatten.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library test;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "dart:async";
+
+static field asy::Future<core::int*>* futureInt = null;
+static field () →* asy::Future<core::int*>* f = () → asy::Future<core::int*>* => self::futureInt;
+static field () →* asy::Future<core::int*>* g = () → asy::Future<core::int*>* async => self::futureInt;
+static method main() → dynamic {
+  self::f;
+  self::g;
+}
diff --git a/pkg/front_end/testcases/inference/async_closure_return_type_future.dart.weak.modular.expect b/pkg/front_end/testcases/inference/async_closure_return_type_future.dart.weak.modular.expect
new file mode 100644
index 0000000..6e90053
--- /dev/null
+++ b/pkg/front_end/testcases/inference/async_closure_return_type_future.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library test;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+static field () →* asy::Future<core::int*>* f = () → asy::Future<core::int*>* async => 0;
+static method main() → dynamic {
+  self::f;
+}
diff --git a/pkg/front_end/testcases/inference/async_closure_return_type_future_or.dart.weak.modular.expect b/pkg/front_end/testcases/inference/async_closure_return_type_future_or.dart.weak.modular.expect
new file mode 100644
index 0000000..a44a6a9
--- /dev/null
+++ b/pkg/front_end/testcases/inference/async_closure_return_type_future_or.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+static field FutureOr<core::int*>* futureOrInt = null;
+static field () →* FutureOr<core::int*>* f = () → FutureOr<core::int*>* => self::futureOrInt;
+static field () →* asy::Future<core::int*>* g = () → asy::Future<core::int*>* async => self::futureOrInt;
+static method main() → dynamic {
+  self::f;
+  self::g;
+}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_async_all_returns_are_futures.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_async_all_returns_are_futures.dart.weak.modular.expect
new file mode 100644
index 0000000..f19d465
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_async_all_returns_are_futures.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library test;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+import "dart:math" as math;
+
+import "dart:async";
+import "dart:math" show Random;
+
+static method test() → dynamic {
+  () →* asy::Future<core::num*>* f = () → asy::Future<core::num*>* async {
+    if(math::Random::•().{math::Random::nextBool}(){() →* core::bool*}) {
+      return asy::Future::value<core::int*>(1);
+    }
+    else {
+      return asy::Future::value<core::double*>(2.0);
+    }
+  };
+  asy::Future<core::num*>* g = f(){() →* asy::Future<core::num*>*};
+  asy::Future<core::int*>* h = f(){() →* asy::Future<core::num*>*} as{TypeError} asy::Future<core::int*>*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_async_all_returns_are_values.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_async_all_returns_are_values.dart.weak.modular.expect
new file mode 100644
index 0000000..419ef81
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_async_all_returns_are_values.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library test;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+import "dart:math" as math;
+
+import "dart:async";
+import "dart:math" show Random;
+
+static method test() → dynamic {
+  () →* asy::Future<core::num*>* f = () → asy::Future<core::num*>* async {
+    if(math::Random::•().{math::Random::nextBool}(){() →* core::bool*}) {
+      return 1;
+    }
+    else {
+      return 2.0;
+    }
+  };
+  asy::Future<core::num*>* g = f(){() →* asy::Future<core::num*>*};
+  asy::Future<core::int*>* h = f(){() →* asy::Future<core::num*>*} as{TypeError} asy::Future<core::int*>*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_async_mix_of_values_and_futures.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_async_mix_of_values_and_futures.dart.weak.modular.expect
new file mode 100644
index 0000000..3af04ad
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_async_mix_of_values_and_futures.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library test;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+import "dart:math" as math;
+
+import "dart:async";
+import "dart:math" show Random;
+
+static method test() → dynamic {
+  () →* asy::Future<core::num*>* f = () → asy::Future<core::num*>* async {
+    if(math::Random::•().{math::Random::nextBool}(){() →* core::bool*}) {
+      return asy::Future::value<core::int*>(1);
+    }
+    else {
+      return 2.0;
+    }
+  };
+  asy::Future<core::num*>* g = f(){() →* asy::Future<core::num*>*};
+  asy::Future<core::int*>* h = f(){() →* asy::Future<core::num*>*} as{TypeError} asy::Future<core::int*>*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_async_star.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_async_star.dart.weak.modular.expect
new file mode 100644
index 0000000..f68b064
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_async_star.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library test;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "dart:async";
+
+static method test() → dynamic {
+  () →* asy::Stream<core::num*>* f = () → asy::Stream<core::num*>* async* {
+    yield 1;
+    asy::Stream<core::double*>* s;
+    yield* s;
+  };
+  asy::Stream<core::num*>* g = f(){() →* asy::Stream<core::num*>*};
+  asy::Stream<core::int*>* h = f(){() →* asy::Stream<core::num*>*} as{TypeError} asy::Stream<core::int*>*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_basic.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_basic.dart.weak.modular.expect
new file mode 100644
index 0000000..add23e8
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_basic.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test1() → dynamic {
+  core::List<core::int*>* o;
+  core::Iterable<core::int*>* y = o.{core::Iterable::map}<core::int*>((core::int* x) → core::int* {
+    return x.{core::num::+}(1){(core::num*) →* core::int*};
+  }){((core::int*) →* core::int*) →* core::Iterable<core::int*>*};
+  core::Iterable<core::int*>* z = y;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_basic_void.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_basic_void.dart.weak.modular.expect
new file mode 100644
index 0000000..446c911
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_basic_void.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method f() → dynamic {
+  core::List<core::int*>* o;
+  o.{core::Iterable::where}((core::int* i) → core::bool* {
+    return i =={core::num::==}{(core::Object*) →* core::bool*} 0;
+  }){((core::int*) →* core::bool*) →* core::Iterable<core::int*>*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_downwards_incompatible_with_upwards_inference.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_downwards_incompatible_with_upwards_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..e90018d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_downwards_incompatible_with_upwards_inference.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/block_bodied_lambdas_downwards_incompatible_with_upwards_inference.dart:12:45: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//     return /*error:RETURN_OF_INVALID_TYPE*/ 1;
+//                                             ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  function f() → core::String*
+    return null;
+  () →* core::String* g = f;
+  g = () → core::String* {
+    return invalid-expression "pkg/front_end/testcases/inference/block_bodied_lambdas_downwards_incompatible_with_upwards_inference.dart:12:45: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+    return /*error:RETURN_OF_INVALID_TYPE*/ 1;
+                                            ^" in 1 as{TypeError} core::String*;
+  };
+}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_downwards_incompatible_with_upwards_inference_top_level.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_downwards_incompatible_with_upwards_inference_top_level.dart.weak.modular.expect
new file mode 100644
index 0000000..f1a6a23
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_downwards_incompatible_with_upwards_inference_top_level.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field () →* core::String* g = #C1;
+static method f() → core::String*
+  return null;
+static method main() → dynamic {
+  #C1;
+}
+
+constants  {
+  #C1 = static-tearoff self::f
+}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_infer_bottom_async.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_infer_bottom_async.dart.weak.modular.expect
new file mode 100644
index 0000000..729dbe7
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_infer_bottom_async.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library test;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "dart:async";
+
+static method main() → dynamic async {
+  () →* asy::Future<Null>* f = () → asy::Future<Null>* async {
+    return null;
+  };
+  asy::Future<dynamic>* y = f(){() →* asy::Future<Null>*};
+  asy::Future<core::String*>* z = f(){() →* asy::Future<Null>*};
+  core::String* s = await f(){() →* asy::Future<Null>*};
+}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_infer_bottom_async_star.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_infer_bottom_async_star.dart.weak.modular.expect
new file mode 100644
index 0000000..a85a79c
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_infer_bottom_async_star.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library test;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "dart:async";
+
+static method main() → dynamic async {
+  () →* asy::Stream<Null>* f = () → asy::Stream<Null>* async* {
+    yield null;
+  };
+  asy::Stream<dynamic>* y = f(){() →* asy::Stream<Null>*};
+  asy::Stream<core::String*>* z = f(){() →* asy::Stream<Null>*};
+  core::String* s = await f(){() →* asy::Stream<Null>*}.{asy::Stream::first}{asy::Future<Null>*};
+}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_infer_bottom_sync.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_infer_bottom_sync.dart.weak.modular.expect
new file mode 100644
index 0000000..4f32533
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_infer_bottom_sync.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field dynamic h = null;
+static method foo((core::Object*) →* core::int* f) → void {}
+static method test() → dynamic {
+  (core::Object*) →* Null f = (core::Object* x) → Null {
+    return null;
+  };
+  core::String* y = f(42){(core::Object*) →* Null};
+  f = (core::Object* x) → Null => "hello" as{TypeError} Null;
+  self::foo((core::Object* x) → Null {
+    return null;
+  });
+  self::foo((core::Object* x) → Null {
+    throw "not implemented";
+  });
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_infer_bottom_sync_star.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_infer_bottom_sync_star.dart.weak.modular.expect
new file mode 100644
index 0000000..579df9a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_infer_bottom_sync_star.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  () →* core::Iterable<Null>* f = () → core::Iterable<Null>* sync* {
+    yield null;
+  };
+  core::Iterable<dynamic>* y = f(){() →* core::Iterable<Null>*};
+  core::Iterable<core::String*>* z = f(){() →* core::Iterable<Null>*};
+  core::String* s = f(){() →* core::Iterable<Null>*}.{core::Iterable::first}{Null};
+}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_lub.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_lub.dart.weak.modular.expect
new file mode 100644
index 0000000..314b863
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_lub.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:math" as math;
+
+import "dart:math" show Random;
+
+static method test2() → dynamic {
+  core::List<core::num*>* o;
+  core::Iterable<core::num*>* y = o.{core::Iterable::map}<core::num*>((core::num* x) → core::num* {
+    if(math::Random::•().{math::Random::nextBool}(){() →* core::bool*}) {
+      return x.{core::num::toInt}(){() →* core::int*}.{core::num::+}(1){(core::num*) →* core::int*};
+    }
+    else {
+      return x.{core::num::toDouble}(){() →* core::double*};
+    }
+  }){((core::num*) →* core::num*) →* core::Iterable<core::num*>*};
+  core::Iterable<core::num*>* w = y;
+  core::Iterable<core::int*>* z = y as{TypeError} core::Iterable<core::int*>*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_nested_lambdas.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_nested_lambdas.dart.weak.modular.expect
new file mode 100644
index 0000000..e9db0d8
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_nested_lambdas.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  () →* (core::int*) →* core::double* f = () → (core::int*) →* core::double* {
+    return (core::int* x) → core::double* {
+      return 2.0.{core::double::*}(x){(core::num*) →* core::double*};
+    };
+  };
+}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_no_return.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_no_return.dart.weak.modular.expect
new file mode 100644
index 0000000..f309388
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_no_return.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test1() → dynamic {
+  core::List<core::int*>* o;
+  core::Iterable<Null>* y = o.{core::Iterable::map}<Null>((core::int* x) → Null {}){((core::int*) →* Null) →* core::Iterable<Null>*};
+  core::Iterable<core::int*>* z = y;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_returns.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_returns.dart.weak.modular.expect
new file mode 100644
index 0000000..39b321c
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_returns.dart.weak.modular.expect
@@ -0,0 +1,99 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/block_bodied_lambdas_returns.dart:35:7: Warning: Must explicitly return a value from a non-void function.
+//       return;
+//       ^
+//
+// pkg/front_end/testcases/inference/block_bodied_lambdas_returns.dart:65:7: Warning: Must explicitly return a value from a non-void function.
+//       return;
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  () →* Null a = () → Null {};
+  () →* Null b = () → Null {
+    return;
+  };
+  () →* Null c = () → Null {
+    return null;
+  };
+  () →* core::int* d = () → core::int* {
+    return 0;
+  };
+  (core::bool*) →* Null e = (core::bool* b) → Null {
+    if(b) {
+      return;
+    }
+    else {
+      return;
+    }
+  };
+  (core::bool*) →* Null f = (core::bool* b) → Null {
+    if(b) {
+      return;
+    }
+    else {
+      return null;
+    }
+  };
+  (core::bool*) →* core::int* g = (core::bool* b) → core::int* {
+    if(b) {
+      return null;
+    }
+    else {
+      return 0;
+    }
+  };
+  (core::bool*) →* Null h = (core::bool* b) → Null {
+    if(b) {
+      return null;
+    }
+    else {
+      return;
+    }
+  };
+  (core::bool*) →* Null i = (core::bool* b) → Null {
+    if(b) {
+      return null;
+    }
+    else {
+      return null;
+    }
+  };
+  (core::bool*) →* core::int* j = (core::bool* b) → core::int* {
+    if(b) {
+      return null;
+    }
+    else {
+      return 0;
+    }
+  };
+  (core::bool*) →* core::int* k = (core::bool* b) → core::int* {
+    if(b) {
+      return 0;
+    }
+    else {
+      return null;
+    }
+  };
+  (core::bool*) →* core::int* l = (core::bool* b) → core::int* {
+    if(b) {
+      return 0;
+    }
+    else {
+      return null;
+    }
+  };
+  (core::bool*) →* core::int* m = (core::bool* b) → core::int* {
+    if(b) {
+      return 0;
+    }
+    else {
+      return 0;
+    }
+  };
+}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_sync_star.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_sync_star.dart.weak.modular.expect
new file mode 100644
index 0000000..09f2baf
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_sync_star.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test() → dynamic {
+  () →* core::Iterable<core::num*>* f = () → core::Iterable<core::num*>* sync* {
+    yield 1;
+    yield*<core::num*>[3, 4.0];
+  };
+  core::Iterable<core::num*>* g = f(){() →* core::Iterable<core::num*>*};
+  core::Iterable<core::int*>* h = f(){() →* core::Iterable<core::num*>*} as{TypeError} core::Iterable<core::int*>*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/block_bodied_lambdas_void_context.dart.weak.modular.expect b/pkg/front_end/testcases/inference/block_bodied_lambdas_void_context.dart.weak.modular.expect
new file mode 100644
index 0000000..246d431
--- /dev/null
+++ b/pkg/front_end/testcases/inference/block_bodied_lambdas_void_context.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method f() → dynamic {
+  core::List<core::int*>* o;
+  o.{core::Iterable::forEach}((core::int* i) → core::int* {
+    return i.{core::num::+}(1){(core::num*) →* core::int*};
+  }){((core::int*) →* void) →* void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/bottom.dart.weak.modular.expect b/pkg/front_end/testcases/inference/bottom.dart.weak.modular.expect
new file mode 100644
index 0000000..d841a5d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/bottom.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library test;
+import self as self;
+
+static field dynamic v = null;
+static method main() → dynamic {
+  self::v;
+}
diff --git a/pkg/front_end/testcases/inference/bottom_in_closure.dart.weak.modular.expect b/pkg/front_end/testcases/inference/bottom_in_closure.dart.weak.modular.expect
new file mode 100644
index 0000000..63cbd26
--- /dev/null
+++ b/pkg/front_end/testcases/inference/bottom_in_closure.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library test;
+import self as self;
+
+static field () →* Null v = () → Null => null;
+static method main() → dynamic {
+  self::v;
+}
diff --git a/pkg/front_end/testcases/inference/bug30251.dart.weak.modular.expect b/pkg/front_end/testcases/inference/bug30251.dart.weak.modular.expect
new file mode 100644
index 0000000..0622d1c
--- /dev/null
+++ b/pkg/front_end/testcases/inference/bug30251.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  final field dynamic x;
+  constructor •(core::int* p) → self::C*
+    : self::C::x = self::f<core::int*>(1.{core::num::+}(p){(core::num*) →* core::int*}), super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>(self::f::T* t) → self::f::T*
+  return t;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/bug30620.dart.weak.modular.expect b/pkg/front_end/testcases/inference/bug30620.dart.weak.modular.expect
new file mode 100644
index 0000000..e2320e0
--- /dev/null
+++ b/pkg/front_end/testcases/inference/bug30620.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  final field core::String* foo;
+  constructor •(core::String* foo) → self::A*
+    : self::A::foo = foo, super core::Object::•()
+    ;
+  operator ==(core::Object* other) → core::bool*
+    return other is self::A* && other{self::A*}.{self::A::foo}{core::String*} =={core::String::==}{(core::Object*) →* core::bool*} this.{self::A::foo}{core::String*};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::print(new self::A::•("hello") =={self::A::==}{(core::Object*) →* core::bool*} new self::A::•("hello"));
+}
diff --git a/pkg/front_end/testcases/inference/bug30620_b.dart.weak.modular.expect b/pkg/front_end/testcases/inference/bug30620_b.dart.weak.modular.expect
new file mode 100644
index 0000000..bc320a3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/bug30620_b.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  final field core::String* foo;
+  constructor •(core::String* foo) → self::A*
+    : self::A::foo = foo, super core::Object::•()
+    ;
+  operator ==(core::Object* other) → core::bool*
+    return other is self::A* && other{self::A*}.{self::A::foo}{core::String*} =={core::String::==}{(core::Object*) →* core::bool*} this.{self::A::foo}{core::String*} && other{self::A*}.{self::A::foo}{core::String*} =={core::String::==}{(core::Object*) →* core::bool*} this.{self::A::foo}{core::String*};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::print(new self::A::•("hello") =={self::A::==}{(core::Object*) →* core::bool*} new self::A::•("hello"));
+}
diff --git a/pkg/front_end/testcases/inference/bug30620_c.dart.weak.modular.expect b/pkg/front_end/testcases/inference/bug30620_c.dart.weak.modular.expect
new file mode 100644
index 0000000..5a1ff19
--- /dev/null
+++ b/pkg/front_end/testcases/inference/bug30620_c.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  final field core::String* foo;
+  constructor •(core::String* foo) → self::A*
+    : self::A::foo = foo, super core::Object::•()
+    ;
+  operator ==(core::Object* other) → core::bool* {
+    if(other is self::A* && other{self::A*}.{self::A::foo}{core::String*} =={core::String::==}{(core::Object*) →* core::bool*} this.{self::A::foo}{core::String*}) {
+      if(other{self::A*}.{self::A::foo}{core::String*} =={core::String::==}{(core::Object*) →* core::bool*} this.{self::A::foo}{core::String*}) {
+      }
+    }
+    return true;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::print(new self::A::•("hello") =={self::A::==}{(core::Object*) →* core::bool*} new self::A::•("hello"));
+}
diff --git a/pkg/front_end/testcases/inference/bug30620_d.dart.weak.modular.expect b/pkg/front_end/testcases/inference/bug30620_d.dart.weak.modular.expect
new file mode 100644
index 0000000..bfc06da
--- /dev/null
+++ b/pkg/front_end/testcases/inference/bug30620_d.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method foo(dynamic obj) → core::String*
+  return obj is core::String* ?{core::String*} obj{core::String*}.{core::String::toUpperCase}(){() →* core::String*} : null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/bug30624.dart.weak.modular.expect b/pkg/front_end/testcases/inference/bug30624.dart.weak.modular.expect
new file mode 100644
index 0000000..630409a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/bug30624.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<E extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::E*>*
+    : super core::Object::•()
+    ;
+  method barA([(self::C::E*, self::C::E*) →* core::int* cmp = #C1]) → void {
+    self::foo<self::C::E*>(this, let final (self::C::E*, self::C::E*) →* core::int* #t1 = cmp in #t1 == null ?{(self::C::E*, self::C::E*) →* core::int*} #C2 : #t1);
+  }
+  method barB([(self::C::E*, self::C::E*) →* core::int* cmp = #C1]) → void {
+    self::foo<self::C::E*>(this, let final (self::C::E*, self::C::E*) →* core::int* #t2 = cmp in #t2 == null ?{(self::C::E*, self::C::E*) →* core::int*} #C2 as (self::C::E*, self::C::E*) →* core::int* : #t2);
+  }
+  method barC([(self::C::E*, self::C::E*) →* core::int* cmp = #C1]) → void {
+    (self::C::E*, self::C::E*) →* core::int* v = #C2;
+    self::foo<self::C::E*>(this, let final (self::C::E*, self::C::E*) →* core::int* #t3 = cmp in #t3 == null ?{(self::C::E*, self::C::E*) →* core::int*} v : #t3);
+  }
+  method barD([(self::C::E*, self::C::E*) →* core::int* cmp = #C1]) → void {
+    self::foo<self::C::E*>(this, let final (self::C::E*, self::C::E*) →* core::int* #t4 = cmp in #t4 == null ?{(self::C::E*, self::C::E*) →* core::int*} #C2 : #t4);
+  }
+  method barE([(self::C::E*, self::C::E*) →* core::int* cmp = #C1]) → void {
+    self::foo<self::C::E*>(this, cmp == null ?{(self::C::E*, self::C::E*) →* core::int*} #C2 : cmp);
+  }
+  method barF([(self::C::E*, self::C::E*) →* core::int* cmp = #C1]) → void {
+    self::foo<self::C::E*>(this, !(cmp == null) ?{(self::C::E*, self::C::E*) →* core::int*} cmp : #C2);
+  }
+  static method _default(dynamic a, dynamic b) → core::int* {
+    return 1.{core::int::unary-}(){() →* core::int*};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo<E extends core::Object* = dynamic>(self::C<self::foo::E*>* c, (self::foo::E*, self::foo::E*) →* core::int* cmp) → void {}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = static-tearoff self::C::_default
+}
diff --git a/pkg/front_end/testcases/inference/bug31132.dart.weak.modular.expect b/pkg/front_end/testcases/inference/bug31132.dart.weak.modular.expect
new file mode 100644
index 0000000..135614f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/bug31132.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B {
+  field dynamic z = null;
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+static method test(self::B* x) → void {
+  self::C* y = x is self::C* ?{self::C*} x{self::C*} : new self::C::•();
+  core::print(y.{self::C::z}{dynamic});
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/bug31133.dart.weak.modular.expect b/pkg/front_end/testcases/inference/bug31133.dart.weak.modular.expect
new file mode 100644
index 0000000..46ea8a2
--- /dev/null
+++ b/pkg/front_end/testcases/inference/bug31133.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  core::int* i = 0;
+  for (final core::int* #t1 = i = i.{core::num::+}(1){(core::num*) →* core::int*}; i.{core::num::<}(10){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+  }
+  for (final core::int* #t2 = i = i.{core::num::+}(1){(core::num*) →* core::int*}; i.{core::num::<}(10){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+  }
+  for (final core::int* #t3 = i = i.{core::num::-}(1){(core::num*) →* core::int*}; i.{core::num::>=}(0){(core::num*) →* core::bool*}; i = i.{core::num::-}(1){(core::num*) →* core::int*}) {
+  }
+  for (final core::int* #t4 = i = i.{core::num::-}(1){(core::num*) →* core::int*}; i.{core::num::>=}(0){(core::num*) →* core::bool*}; i = i.{core::num::-}(1){(core::num*) →* core::int*}) {
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/bug31436.dart.weak.modular.expect b/pkg/front_end/testcases/inference/bug31436.dart.weak.modular.expect
new file mode 100644
index 0000000..adc6d4a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/bug31436.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method block_test() → void {
+  () →* core::List<core::Object*>* g;
+  g = () → core::List<core::Object*>* {
+    return <core::Object*>[3];
+  };
+  assert(g is () →* core::List<core::Object*>*);
+  assert(!(g is () →* core::List<core::int*>*));
+  g(){() →* core::List<core::Object*>*}.{core::List::add}("hello"){(core::Object*) →* void};
+  core::List<core::int*>* l = <core::int*>[3];
+  g = () → core::List<core::int*>* {
+    return l;
+  };
+  assert(g is () →* core::List<core::Object*>*);
+  assert(g is () →* core::List<core::int*>*);
+  try {
+    g(){() →* core::List<core::Object*>*}.{core::List::add}("hello"){(core::Object*) →* void};
+    throw "expected a runtime error";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+  core::Object* o = l;
+  g = () → core::List<core::Object*>* {
+    return o as{TypeError} core::List<core::Object*>*;
+  };
+  assert(g is () →* core::List<core::Object*>*);
+  assert(!(g is () →* core::List<core::int*>*));
+  assert(!(g is () →* core::Object*));
+  g(){() →* core::List<core::Object*>*};
+  o = 3;
+  try {
+    g(){() →* core::List<core::Object*>*};
+    throw "expected a runtime error";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
+static method arrow_test() → void {
+  () →* core::List<core::Object*>* g;
+  g = () → core::List<core::Object*>* => <core::Object*>[3];
+  assert(g is () →* core::List<core::Object*>*);
+  assert(!(g is () →* core::List<core::int*>*));
+  g(){() →* core::List<core::Object*>*}.{core::List::add}("hello"){(core::Object*) →* void};
+  core::List<core::int*>* l = <core::int*>[3];
+  g = () → core::List<core::int*>* => l;
+  assert(g is () →* core::List<core::Object*>*);
+  assert(g is () →* core::List<core::int*>*);
+  try {
+    g(){() →* core::List<core::Object*>*}.{core::List::add}("hello"){(core::Object*) →* void};
+    throw "expected a runtime error";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+  core::Object* o = l;
+  g = () → core::List<core::Object*>* => o as{TypeError} core::List<core::Object*>*;
+  assert(g is () →* core::List<core::Object*>*);
+  assert(!(g is () →* core::List<core::int*>*));
+  assert(!(g is () →* core::Object*));
+  g(){() →* core::List<core::Object*>*};
+  o = 3;
+  try {
+    g(){() →* core::List<core::Object*>*};
+    throw "expected a runtime error";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
+static method main() → dynamic {
+  self::block_test();
+  self::arrow_test();
+}
diff --git a/pkg/front_end/testcases/inference/bug32291.dart.weak.modular.expect b/pkg/front_end/testcases/inference/bug32291.dart.weak.modular.expect
new file mode 100644
index 0000000..b473c4f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/bug32291.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → void {
+  core::List<core::List<core::String*>*>* l = <core::List<core::String*>*>[<core::String*>["hi", "world"]];
+  core::Iterable<core::List<core::String*>*>* i1 = l.{core::Iterable::map}<core::List<core::String*>*>((core::List<core::String*>* ll) → core::List<core::String*>* => let final core::List<core::String*>* #t1 = ll in #t1 == null ?{core::List<core::String*>*} <core::String*>[] : #t1){((core::List<core::String*>*) →* core::List<core::String*>*) →* core::Iterable<core::List<core::String*>*>*};
+  core::Iterable<core::int*>* i2 = i1.{core::Iterable::map}<core::int*>((core::List<core::String*>* l) → core::int* => l.{core::List::length}{core::int*}){((core::List<core::String*>*) →* core::int*) →* core::Iterable<core::int*>*};
+  core::print(i2);
+}
diff --git a/pkg/front_end/testcases/inference/bug33324.dart.weak.modular.expect b/pkg/front_end/testcases/inference/bug33324.dart.weak.modular.expect
new file mode 100644
index 0000000..318df8a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/bug33324.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method foo() → core::int* {
+  core::Function* f = (dynamic x) → dynamic => x;
+  core::List<dynamic>* l = <core::String*>["bar"].{core::Iterable::map}<dynamic>(f as{TypeError} (core::String*) →* dynamic){((core::String*) →* dynamic) →* core::Iterable<dynamic>*}.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<dynamic>*};
+  l.{core::List::add}(42){(dynamic) →* void};
+  return l.{core::Iterable::first}{dynamic}{dynamic}.length as{TypeError,ForDynamic} core::int*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/call_corner_cases.dart.weak.modular.expect b/pkg/front_end/testcases/inference/call_corner_cases.dart.weak.modular.expect
new file mode 100644
index 0000000..bc9a2a22
--- /dev/null
+++ b/pkg/front_end/testcases/inference/call_corner_cases.dart.weak.modular.expect
@@ -0,0 +1,67 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method call() → core::int*
+    return 0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  get call() → self::A*
+    return new self::A::•();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends core::Object {
+  field self::A* fieldA = new self::A::•();
+  field self::B* fieldB = new self::B::•();
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  get getA() → self::A*
+    return new self::A::•();
+  get getB() → self::B*
+    return new self::B::•();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  core::int* callA = new self::A::•().{self::A::call}(){() →* core::int*};
+  core::int* callFieldA = new self::D::•().{self::D::fieldA}{self::A*}.{self::A::call}(){() →* core::int*};
+  core::int* callGetA = new self::D::•().{self::D::getA}{self::A*}.{self::A::call}(){() →* core::int*};
+  core::int* callFieldB = new self::D::•().{self::D::fieldB}{self::B*}.{self::B::call}{self::A*}.{self::A::call}(){() →* core::int*};
+  core::int* callGetB = new self::D::•().{self::D::getB}{self::B*}.{self::B::call}{self::A*}.{self::A::call}(){() →* core::int*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/callable_generic_class.dart.weak.modular.expect b/pkg/front_end/testcases/inference/callable_generic_class.dart.weak.modular.expect
new file mode 100644
index 0000000..36688cc
--- /dev/null
+++ b/pkg/front_end/testcases/inference/callable_generic_class.dart.weak.modular.expect
@@ -0,0 +1,61 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class ActionDispatcher<P extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::ActionDispatcher<self::ActionDispatcher::P*>*
+    : super core::Object::•()
+    ;
+  method call([covariant-by-class self::ActionDispatcher::P* value = #C1]) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar extends core::Object {
+  synthetic constructor •() → self::Bar*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class FooActions extends core::Object {
+  synthetic constructor •() → self::FooActions*
+    : super core::Object::•()
+    ;
+  get foo() → self::ActionDispatcher<self::Bar*>*
+    return new self::ActionDispatcher::•<self::Bar*>();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {
+  let final self::FooActions* #t1 = new self::FooActions::•() in let final self::Bar* #t2 = new self::Bar::•() in #t1.{self::FooActions::foo}{self::ActionDispatcher<self::Bar*>*}.{self::ActionDispatcher::call}(#t2){([self::Bar*]) →* void};
+  new self::FooActions::•().{self::FooActions::foo}{self::ActionDispatcher<self::Bar*>*}.{self::ActionDispatcher::call}(new self::Bar::•()){([self::Bar*]) →* void};
+  new self::FooActions::•().{self::FooActions::foo}{self::ActionDispatcher<self::Bar*>*}.{self::ActionDispatcher::call}(new self::Bar::•()){([self::Bar*]) →* void};
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/inference/circular_method_inference.dart.weak.modular.expect b/pkg/front_end/testcases/inference/circular_method_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..1bacd22
--- /dev/null
+++ b/pkg/front_end/testcases/inference/circular_method_inference.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/circular_method_inference.dart:12:16: Error: 'A' is a supertype of itself.
+// abstract class A extends B {
+//                ^
+//
+// pkg/front_end/testcases/inference/circular_method_inference.dart:16:16: Error: 'B' is a supertype of itself.
+// abstract class B extends A {
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract method f(dynamic x) → dynamic;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract method f(dynamic x) → dynamic;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/circular_reference_via_closures.dart.weak.modular.expect b/pkg/front_end/testcases/inference/circular_reference_via_closures.dart.weak.modular.expect
new file mode 100644
index 0000000..189aa8d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/circular_reference_via_closures.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/circular_reference_via_closures.dart:8:5: Error: Can't infer the type of 'x': circularity found during type inference.
+// Specify the type explicitly.
+// var x = /*@ returnType=() ->* invalid-type */ () => y;
+//     ^
+//
+import self as self;
+
+static field invalid-type x = () → () →* invalid-type => self::y;
+static field () →* invalid-type y = () → invalid-type => self::x;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/circular_reference_via_closures_initializer_types.dart.weak.modular.expect b/pkg/front_end/testcases/inference/circular_reference_via_closures_initializer_types.dart.weak.modular.expect
new file mode 100644
index 0000000..2439199
--- /dev/null
+++ b/pkg/front_end/testcases/inference/circular_reference_via_closures_initializer_types.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/circular_reference_via_closures_initializer_types.dart:8:5: Error: Can't infer the type of 'x': circularity found during type inference.
+// Specify the type explicitly.
+// var x = /*@ returnType=() ->* invalid-type */ () => y;
+//     ^
+//
+import self as self;
+
+static field invalid-type x = () → () →* invalid-type => self::y;
+static field () →* invalid-type y = () → invalid-type => self::x;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/closure_param_null_to_object.dart.weak.modular.expect b/pkg/front_end/testcases/inference/closure_param_null_to_object.dart.weak.modular.expect
new file mode 100644
index 0000000..1937cae
--- /dev/null
+++ b/pkg/front_end/testcases/inference/closure_param_null_to_object.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  (Null) →* core::int* f = (core::Object* x) → core::int* => 1;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/coerce_bottom_and_null_types.dart.weak.modular.expect b/pkg/front_end/testcases/inference/coerce_bottom_and_null_types.dart.weak.modular.expect
new file mode 100644
index 0000000..9396c77
--- /dev/null
+++ b/pkg/front_end/testcases/inference/coerce_bottom_and_null_types.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method f() → dynamic {
+  core::int* a = 0;
+  dynamic b = null;
+  dynamic c = throw "foo";
+  () →* core::int* d = () → core::int* => 0;
+  () →* Null e = () → Null => null;
+  () →* Null f = () → Null => throw "foo";
+  () →* core::int* g = () → core::int* {
+    return 0;
+  };
+  () →* Null h = () → Null {
+    return null;
+  };
+  () →* Null i = () → Null {
+    return throw "foo";
+  };
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/complex_predecrement.dart.weak.modular.expect b/pkg/front_end/testcases/inference/complex_predecrement.dart.weak.modular.expect
new file mode 100644
index 0000000..a27510a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/complex_predecrement.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::List<core::int*>* foo = <core::int*>[1, 2, 3];
+  core::print(let final core::List<core::int*>* #t1 = foo in let final core::int* #t2 = 0 in let final core::int* #t3 = #t1.{core::List::[]}(#t2){(core::int*) →* core::int*}.{core::num::-}(1){(core::num*) →* core::int*} in let final void #t4 = #t1.{core::List::[]=}(#t2, #t3){(core::int*, core::int*) →* void} in #t3);
+}
diff --git a/pkg/front_end/testcases/inference/conditional_lub.dart.weak.modular.expect b/pkg/front_end/testcases/inference/conditional_lub.dart.weak.modular.expect
new file mode 100644
index 0000000..0d65f10
--- /dev/null
+++ b/pkg/front_end/testcases/inference/conditional_lub.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::bool* b = true;
+static field core::int* x = 0;
+static field core::double* y = 0.0;
+static field core::num* z = self::b ?{core::num*} self::x : self::y;
+static method main() → dynamic {
+  core::num* z = self::b ?{core::num*} self::x : self::y;
+}
diff --git a/pkg/front_end/testcases/inference/conditional_upwards_inference.dart.weak.modular.expect b/pkg/front_end/testcases/inference/conditional_upwards_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..c929f40
--- /dev/null
+++ b/pkg/front_end/testcases/inference/conditional_upwards_inference.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(core::List<self::C::T*>* x) → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::bool* b = false;
+  core::List<core::int*>* l1 = <core::int*>[1];
+  core::List<core::int*>* l2 = <core::int*>[2];
+  self::C<core::int*>* x = new self::C::•<core::int*>(l1);
+  self::C<core::int*>* y = new self::C::•<core::int*>(l2);
+  self::C<core::int*>* z = new self::C::•<core::int*>(b ?{core::List<core::int*>*} l1 : l2);
+}
diff --git a/pkg/front_end/testcases/inference/conflicting_fields.dart.weak.modular.expect b/pkg/front_end/testcases/inference/conflicting_fields.dart.weak.modular.expect
new file mode 100644
index 0000000..24a2f0c
--- /dev/null
+++ b/pkg/front_end/testcases/inference/conflicting_fields.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field dynamic field1 = null;
+  field core::int* field2 = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class I extends core::Object {
+  field core::int* field1 = null;
+  field dynamic field2 = null;
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A implements self::I {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  get field1() → core::int*
+    return null;
+  get field2() → core::int*
+    return null;
+  set field1(dynamic value) → void {}
+  set field2(dynamic value) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/conflicts_can_happen.dart.weak.modular.expect b/pkg/front_end/testcases/inference/conflicts_can_happen.dart.weak.modular.expect
new file mode 100644
index 0000000..edd05fe
--- /dev/null
+++ b/pkg/front_end/testcases/inference/conflicts_can_happen.dart.weak.modular.expect
@@ -0,0 +1,93 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class I1 extends core::Object {
+  field core::int* x = null;
+  synthetic constructor •() → self::I1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class I2 extends self::I1 {
+  field core::int* y = null;
+  synthetic constructor •() → self::I2*
+    : super self::I1::•()
+    ;
+}
+class A extends core::Object {
+  final field self::I1* a = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  final field self::I2* a = null;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C1 extends core::Object implements self::A, self::B {
+  synthetic constructor •() → self::C1*
+    : super core::Object::•()
+    ;
+  get a() → self::I2*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C2 extends core::Object implements self::B, self::A {
+  synthetic constructor •() → self::C2*
+    : super core::Object::•()
+    ;
+  get a() → self::I2*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/conflicts_can_happen2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/conflicts_can_happen2.dart.weak.modular.expect
new file mode 100644
index 0000000..f8a6f85
--- /dev/null
+++ b/pkg/front_end/testcases/inference/conflicts_can_happen2.dart.weak.modular.expect
@@ -0,0 +1,134 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/conflicts_can_happen2.dart:34:7: Error: Can't infer a return type for 'a' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   get a => null;
+//       ^
+// pkg/front_end/testcases/inference/conflicts_can_happen2.dart:22:12: Context: This is one of the overridden members.
+//   final I1 a = null;
+//            ^
+// pkg/front_end/testcases/inference/conflicts_can_happen2.dart:26:12: Context: This is one of the overridden members.
+//   final I2 a = null;
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class I1 extends core::Object {
+  field core::int* x = null;
+  synthetic constructor •() → self::I1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class I2 extends core::Object {
+  field core::int* y = null;
+  synthetic constructor •() → self::I2*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class I3 extends core::Object implements self::I1, self::I2 {
+  field core::int* x = null;
+  field core::int* y = null;
+  synthetic constructor •() → self::I3*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends core::Object {
+  final field self::I1* a = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  final field self::I2* a = null;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C1 extends core::Object implements self::A, self::B {
+  synthetic constructor •() → self::C1*
+    : super core::Object::•()
+    ;
+  get a() → self::I3*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C2 extends core::Object implements self::A, self::B {
+  synthetic constructor •() → self::C2*
+    : super core::Object::•()
+    ;
+  get a() → invalid-type
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/constructors_downwards_with_constraint.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_downwards_with_constraint.dart.weak.modular.expect
new file mode 100644
index 0000000..7a1c1c0
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_downwards_with_constraint.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class Foo<T extends self::A*> extends core::Object {
+  synthetic constructor •() → self::Foo<self::Foo::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {
+  self::Foo<self::B*>* foo = new self::Foo::•<self::B*>();
+}
diff --git a/pkg/front_end/testcases/inference/constructors_infer_from_arguments.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_infer_from_arguments.dart.weak.modular.expect
new file mode 100644
index 0000000..1797fc0
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_infer_from_arguments.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/constructors_infer_from_arguments.dart:26:55: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   x. /*@target=C.t*/ t = /*error:INVALID_ASSIGNMENT*/ 'hello';
+//                                                       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::C::T* t;
+  constructor •(self::C::T* t) → self::C<self::C::T*>*
+    : self::C::t = t, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  self::C<core::int*>* x = new self::C::•<core::int*>(42);
+  core::num* y;
+  self::C<core::int*>* c_int = new self::C::•<core::int*>(y as{TypeError} core::int*);
+  self::C<core::num*>* c_num = new self::C::•<core::num*>(123);
+  self::C<core::num*>* c_num2 = let final self::C<core::num*>* #t1 = new self::C::•<core::num*>(456) in block {
+    #t1.{self::C::t} = 1.0;
+  } =>#t1;
+  self::C<dynamic>* c_dynamic = new self::C::•<dynamic>(42);
+  x.{self::C::t} = invalid-expression "pkg/front_end/testcases/inference/constructors_infer_from_arguments.dart:26:55: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  x. /*@target=C.t*/ t = /*error:INVALID_ASSIGNMENT*/ 'hello';
+                                                      ^" in "hello" as{TypeError} core::int*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/constructors_infer_from_arguments_argument_not_assignable.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_argument_not_assignable.dart.weak.modular.expect
new file mode 100644
index 0000000..3ed0854
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_argument_not_assignable.dart.weak.modular.expect
@@ -0,0 +1,82 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/constructors_infer_from_arguments_argument_not_assignable.dart:22:59: Error: Inferred type argument 'NotA' doesn't conform to the bound 'A' of the type variable 'T' on 'C'.
+//  - 'NotA' is from 'pkg/front_end/testcases/inference/constructors_infer_from_arguments_argument_not_assignable.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/inference/constructors_infer_from_arguments_argument_not_assignable.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//       new /*error:COULD_NOT_INFER*/ /*@ typeArgs=NotA* */ C(myF);
+//                                                           ^
+// pkg/front_end/testcases/inference/constructors_infer_from_arguments_argument_not_assignable.dart:12:9: Context: This is the type variable whose bound isn't conformed to.
+// class C<T extends A> {
+//         ^
+//
+// pkg/front_end/testcases/inference/constructors_infer_from_arguments_argument_not_assignable.dart:21:29: Error: Inferred type argument 'NotA' doesn't conform to the bound 'A' of the type variable 'T' on 'C'.
+//  - 'NotA' is from 'pkg/front_end/testcases/inference/constructors_infer_from_arguments_argument_not_assignable.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/inference/constructors_infer_from_arguments_argument_not_assignable.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   var /*@ type=C<NotA*>* */ x =
+//                             ^
+// pkg/front_end/testcases/inference/constructors_infer_from_arguments_argument_not_assignable.dart:12:9: Context: This is the type variable whose bound isn't conformed to.
+// class C<T extends A> {
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F<T extends core::Object* = dynamic> = () →* T*;
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<T extends self::A*> extends core::Object {
+  constructor •(() →* self::C::T* f) → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class NotA extends core::Object {
+  synthetic constructor •() → self::NotA*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method myF() → self::NotA*
+  return null;
+static method main() → dynamic {
+  self::C<self::NotA*>* x = new self::C::•<self::NotA*>(#C1);
+}
+
+constants  {
+  #C1 = static-tearoff self::myF
+}
diff --git a/pkg/front_end/testcases/inference/constructors_infer_from_arguments_const.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_const.dart.weak.modular.expect
new file mode 100644
index 0000000..5cf994f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_const.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field self::C::T* t;
+  const constructor •(self::C::T* t) → self::C<self::C::T*>*
+    : self::C::t = t, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C<core::int*>* x = #C2;
+}
+
+constants  {
+  #C1 = 42
+  #C2 = self::C<core::int*> {t:#C1}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///constructors_infer_from_arguments_const.dart:
+- C. (from org-dartlang-testcase:///constructors_infer_from_arguments_const.dart:10:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/inference/constructors_infer_from_arguments_const_with_upper_bound.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_const_with_upper_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..c79ff6d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_const_with_upper_bound.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::num*> extends core::Object /*hasConstConstructor*/  {
+  final field self::C::T* x;
+  const constructor •(self::C::T* x) → self::C<self::C::T*>*
+    : self::C::x = x, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<T extends core::num*> extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {
+  self::C<core::int*>* c2 = #C2;
+}
+
+constants  {
+  #C1 = 0
+  #C2 = self::C<core::int*> {x:#C1}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///constructors_infer_from_arguments_const_with_upper_bound.dart:
+- C. (from org-dartlang-testcase:///constructors_infer_from_arguments_const_with_upper_bound.dart:10:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- D. (from org-dartlang-testcase:///constructors_infer_from_arguments_const_with_upper_bound.dart:14:9)
diff --git a/pkg/front_end/testcases/inference/constructors_infer_from_arguments_downwards_from_constructor.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_downwards_from_constructor.dart.weak.modular.expect
new file mode 100644
index 0000000..760a01e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_downwards_from_constructor.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(core::List<self::C::T*>* list) → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C<core::int*>* x = new self::C::•<core::int*>(<core::int*>[123]);
+  self::C<core::int*>* y = x;
+  self::C<dynamic>* a = new self::C::•<dynamic>(<dynamic>[123]);
+  self::C<core::Object*>* b = new self::C::•<core::Object*>(<core::Object*>[123]);
+}
diff --git a/pkg/front_end/testcases/inference/constructors_infer_from_arguments_factory.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_factory.dart.weak.modular.expect
new file mode 100644
index 0000000..32c7a0d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_factory.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/constructors_infer_from_arguments_factory.dart:22:3: Error: Setter not found: 't'.
+//   t = /*error:INVALID_ASSIGNMENT*/ 'hello';
+//   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::C::T* t = null;
+  constructor _() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  static factory •<T extends core::Object* = dynamic>(self::C::•::T* t) → self::C<self::C::•::T*>* {
+    self::C<self::C::•::T*>* x = new self::C::_<self::C::•::T*>();
+    t = t;
+    return x;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  self::C<core::int*>* x = self::C::•<core::int*>(42);
+  invalid-expression "pkg/front_end/testcases/inference/constructors_infer_from_arguments_factory.dart:22:3: Error: Setter not found: 't'.
+  t = /*error:INVALID_ASSIGNMENT*/ 'hello';
+  ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/constructors_infer_from_arguments_factory_calls_constructor.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_factory_calls_constructor.dart.weak.modular.expect
new file mode 100644
index 0000000..ba0e34d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_factory_calls_constructor.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::A<self::A::T*>* f = new self::A::•<self::A::T*>();
+  constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  static factory factory<T extends core::Object* = dynamic>() → self::A<self::A::factory::T*>*
+    return new self::A::•<self::A::factory::T*>();
+  method m() → self::A<self::A::T*>*
+    return new self::A::•<self::A::T*>();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/constructors_infer_from_arguments_named.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_named.dart.weak.modular.expect
new file mode 100644
index 0000000..adf0647
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_named.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::C::T* t = null;
+  constructor named(core::List<self::C::T*>* t) → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C<core::int*>* x = new self::C::named<core::int*>(<core::int*>[]);
+}
diff --git a/pkg/front_end/testcases/inference/constructors_infer_from_arguments_named_factory.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_named_factory.dart.weak.modular.expect
new file mode 100644
index 0000000..c030443
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_named_factory.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::C::T* t = null;
+  constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  static factory named<T extends core::Object* = dynamic>(self::C::named::T* t) → self::C<self::C::named::T*>* {
+    self::C<self::C::named::T*>* x = new self::C::•<self::C::named::T*>();
+    x.{self::C::t} = t;
+    return x;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C<core::int*>* x = self::C::named<core::int*>(42);
+}
diff --git a/pkg/front_end/testcases/inference/constructors_infer_from_arguments_redirecting.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_redirecting.dart.weak.modular.expect
new file mode 100644
index 0000000..b9202f7
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_redirecting.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::C::T* t;
+  constructor •(self::C::T* t) → self::C<self::C::T*>*
+    : self::C::t = t, super core::Object::•()
+    ;
+  constructor named(core::List<self::C::T*>* t) → self::C<self::C::T*>*
+    : this self::C::•(t.{core::List::[]}(0){(core::int*) →* self::C::T*})
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C<core::int*>* x = new self::C::named<core::int*>(<core::int*>[42]);
+}
diff --git a/pkg/front_end/testcases/inference/constructors_infer_from_arguments_redirecting_factory.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_redirecting_factory.dart.weak.modular.expect
new file mode 100644
index 0000000..7f8c3dd
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_redirecting_factory.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class C<T extends core::Object* = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  abstract get t() → self::C::T*;
+  abstract set t(covariant-by-class self::C::T* x) → void;
+  static factory •<T extends core::Object* = dynamic>(self::C::•::T* t) → self::C<self::C::•::T*>*
+    return new self::CImpl::•<self::C::•::T*>(t);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class CImpl<T extends core::Object* = dynamic> extends core::Object implements self::C<self::CImpl::T*> {
+  covariant-by-class field self::CImpl::T* t;
+  constructor •(self::CImpl::T* t) → self::CImpl<self::CImpl::T*>*
+    : self::CImpl::t = t, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C<core::int*>* x = new self::CImpl::•<core::int*>(42);
+}
+
+constants  {
+  #C1 = constructor-tearoff self::C::•
+}
diff --git a/pkg/front_end/testcases/inference/constructors_infer_from_arguments_redirecting_factory_to_factory.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_redirecting_factory_to_factory.dart.weak.modular.expect
new file mode 100644
index 0000000..a2fd0ae
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_infer_from_arguments_redirecting_factory_to_factory.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class C<T extends core::Object* = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  abstract get t() → self::C::T*;
+  abstract set t(covariant-by-class self::C::T* x) → void;
+  static factory •<T extends core::Object* = dynamic>(self::C::•::T* t) → self::C<self::C::•::T*>*
+    return self::CImpl::•<self::C::•::T*>(t);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class CImpl<T extends core::Object* = dynamic> extends core::Object implements self::C<self::CImpl::T*> {
+  covariant-by-class field self::CImpl::T* t;
+  constructor _(self::CImpl::T* t) → self::CImpl<self::CImpl::T*>*
+    : self::CImpl::t = t, super core::Object::•()
+    ;
+  static factory •<T extends core::Object* = dynamic>(self::CImpl::•::T* t) → self::CImpl<self::CImpl::•::T*>*
+    return new self::CImpl::_<self::CImpl::•::T*>(t);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C<core::int*>* x = self::CImpl::•<core::int*>(42);
+}
+
+constants  {
+  #C1 = constructor-tearoff self::C::•
+}
diff --git a/pkg/front_end/testcases/inference/constructors_inference_f_bounded.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_inference_f_bounded.dart.weak.modular.expect
new file mode 100644
index 0000000..5ef8772
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_inference_f_bounded.dart.weak.modular.expect
@@ -0,0 +1,65 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/constructors_inference_f_bounded.dart:22:116: Error: Inferred type argument 'Cloneable<dynamic>' doesn't conform to the bound 'Cloneable<T>' of the type variable 'T' on 'Pair'.
+//  - 'Cloneable' is from 'pkg/front_end/testcases/inference/constructors_inference_f_bounded.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//       new /*error:COULD_NOT_INFER,error:COULD_NOT_INFER*/ /*@ typeArgs=Cloneable<dynamic>*, Cloneable<dynamic>* */ Pair
+//                                                                                                                    ^
+// pkg/front_end/testcases/inference/constructors_inference_f_bounded.dart:10:12: Context: This is the type variable whose bound isn't conformed to.
+// class Pair<T extends Cloneable<T>, U extends Cloneable<U>> {
+//            ^
+//
+// pkg/front_end/testcases/inference/constructors_inference_f_bounded.dart:22:116: Error: Inferred type argument 'Cloneable<dynamic>' doesn't conform to the bound 'Cloneable<U>' of the type variable 'U' on 'Pair'.
+//  - 'Cloneable' is from 'pkg/front_end/testcases/inference/constructors_inference_f_bounded.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//       new /*error:COULD_NOT_INFER,error:COULD_NOT_INFER*/ /*@ typeArgs=Cloneable<dynamic>*, Cloneable<dynamic>* */ Pair
+//                                                                                                                    ^
+// pkg/front_end/testcases/inference/constructors_inference_f_bounded.dart:10:36: Context: This is the type variable whose bound isn't conformed to.
+// class Pair<T extends Cloneable<T>, U extends Cloneable<U>> {
+//                                    ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Cloneable<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Cloneable<self::Cloneable::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Pair<T extends self::Cloneable<self::Pair::T*>* = self::Cloneable<dynamic>*, U extends self::Cloneable<self::Pair::U*>* = self::Cloneable<dynamic>*> extends core::Object {
+  covariant-by-class field self::Pair::T* t;
+  covariant-by-class field self::Pair::U* u;
+  constructor •(self::Pair::T* t, self::Pair::U* u) → self::Pair<self::Pair::T*, self::Pair::U*>*
+    : self::Pair::t = t, self::Pair::u = u, super core::Object::•()
+    ;
+  constructor _() → self::Pair<self::Pair::T*, self::Pair::U*>*
+    : self::Pair::u = null, self::Pair::t = null, super core::Object::•()
+    ;
+  get reversed() → self::Pair<self::Pair::U*, self::Pair::T*>*
+    return new self::Pair::•<self::Pair::U*, self::Pair::T*>(this.{self::Pair::u}{self::Pair::U*}, this.{self::Pair::t}{self::Pair::T*});
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  final self::Pair<self::Cloneable<dynamic>*, self::Cloneable<dynamic>*>* x = new self::Pair::_<self::Cloneable<dynamic>*, self::Cloneable<dynamic>*>();
+}
diff --git a/pkg/front_end/testcases/inference/constructors_reverse_type_parameters.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_reverse_type_parameters.dart.weak.modular.expect
new file mode 100644
index 0000000..f36fcca
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_reverse_type_parameters.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Pair<T extends core::Object* = dynamic, U extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::Pair::T* t;
+  covariant-by-class field self::Pair::U* u;
+  constructor •(self::Pair::T* t, self::Pair::U* u) → self::Pair<self::Pair::T*, self::Pair::U*>*
+    : self::Pair::t = t, self::Pair::u = u, super core::Object::•()
+    ;
+  get reversed() → self::Pair<self::Pair::U*, self::Pair::T*>*
+    return new self::Pair::•<self::Pair::U*, self::Pair::T*>(this.{self::Pair::u}{self::Pair::U*}, this.{self::Pair::t}{self::Pair::T*});
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/constructors_too_many_positional_arguments.dart.weak.modular.expect b/pkg/front_end/testcases/inference/constructors_too_many_positional_arguments.dart.weak.modular.expect
new file mode 100644
index 0000000..63ca562
--- /dev/null
+++ b/pkg/front_end/testcases/inference/constructors_too_many_positional_arguments.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/constructors_too_many_positional_arguments.dart:11:77: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//   var /*@type=invalid-type*/ a = new A /*error:EXTRA_POSITIONAL_ARGUMENTS*/ (42);
+//                                                                             ^
+// pkg/front_end/testcases/inference/constructors_too_many_positional_arguments.dart:8:7: Context: The class 'A' has a constructor that takes no arguments.
+// class A<T> {}
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  invalid-type a = invalid-expression "pkg/front_end/testcases/inference/constructors_too_many_positional_arguments.dart:11:77: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+  var /*@type=invalid-type*/ a = new A /*error:EXTRA_POSITIONAL_ARGUMENTS*/ (42);
+                                                                            ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/do_not_infer_overridden_fields_that_explicitly_say_dynamic_infer.dart.weak.modular.expect b/pkg/front_end/testcases/inference/do_not_infer_overridden_fields_that_explicitly_say_dynamic_infer.dart.weak.modular.expect
new file mode 100644
index 0000000..51015b3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/do_not_infer_overridden_fields_that_explicitly_say_dynamic_infer.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/do_not_infer_overridden_fields_that_explicitly_say_dynamic_infer.dart:13:49: Error: The return type of the method 'B.x' is 'dynamic', which does not match the return type, 'int', of the overridden method, 'A.x'.
+// Change to a subtype of 'int'.
+//   /*error:INVALID_METHOD_OVERRIDE*/ dynamic get x => 3;
+//                                                 ^
+// pkg/front_end/testcases/inference/do_not_infer_overridden_fields_that_explicitly_say_dynamic_infer.dart:9:13: Context: This is the overridden method ('x').
+//   final int x = 2;
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  final field core::int* x = 2;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::A {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  get x() → dynamic
+    return 3;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo() → dynamic {
+  core::String* y = new self::B::•().{self::B::x}{dynamic} as{TypeError,ForDynamic} core::String*;
+  core::int* z = new self::B::•().{self::B::x}{dynamic} as{TypeError,ForDynamic} core::int*;
+}
+static method main() → dynamic {
+  self::foo();
+}
diff --git a/pkg/front_end/testcases/inference/dont_infer_field_type_when_initializer_is_null.dart.weak.modular.expect b/pkg/front_end/testcases/inference/dont_infer_field_type_when_initializer_is_null.dart.weak.modular.expect
new file mode 100644
index 0000000..9adf7a2
--- /dev/null
+++ b/pkg/front_end/testcases/inference/dont_infer_field_type_when_initializer_is_null.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  static field dynamic x = null;
+  static field core::int* y = 3;
+  field dynamic x2 = null;
+  field core::int* y2 = 3;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field dynamic x = null;
+static field core::int* y = 3;
+static method main() → dynamic {
+  self::x;
+  self::y;
+}
diff --git a/pkg/front_end/testcases/inference/dont_infer_type_on_dynamic.dart.weak.modular.expect b/pkg/front_end/testcases/inference/dont_infer_type_on_dynamic.dart.weak.modular.expect
new file mode 100644
index 0000000..6fc489d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/dont_infer_type_on_dynamic.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library test;
+import self as self;
+
+static method test() → dynamic {
+  dynamic x = 3;
+  x = "hi";
+}
+static method main() → dynamic {
+  self::test();
+}
diff --git a/pkg/front_end/testcases/inference/dont_infer_type_when_initializer_is_null.dart.weak.modular.expect b/pkg/front_end/testcases/inference/dont_infer_type_when_initializer_is_null.dart.weak.modular.expect
new file mode 100644
index 0000000..7dd89fd
--- /dev/null
+++ b/pkg/front_end/testcases/inference/dont_infer_type_when_initializer_is_null.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library test;
+import self as self;
+
+static method test() → dynamic {
+  dynamic x = null;
+  x = "hi";
+  x = 3;
+}
+static method main() → dynamic {
+  self::test();
+}
diff --git a/pkg/front_end/testcases/inference/downward_inference_fixes_no_upwards_errors.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downward_inference_fixes_no_upwards_errors.dart.weak.modular.expect
new file mode 100644
index 0000000..c7d6e17
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downward_inference_fixes_no_upwards_errors.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/downward_inference_fixes_no_upwards_errors.dart:21:65: Error: Inferred type argument 'dynamic' doesn't conform to the bound 'num' of the type variable 'T' on 'max'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   dynamic c = /*error:COULD_NOT_INFER*/ /*@ typeArgs=dynamic */ max(x, y);
+//                                                                 ^
+//
+// pkg/front_end/testcases/inference/downward_inference_fixes_no_upwards_errors.dart:22:81: Error: Inferred type argument 'dynamic' doesn't conform to the bound 'num' of the type variable 'T' on 'max'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   var /*@ type=dynamic */ d = /*error:COULD_NOT_INFER*/ /*@ typeArgs=dynamic */ max(
+//                                                                                 ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:math" as math;
+
+import "dart:math";
+
+static method f() → dynamic {
+  core::num* x;
+  dynamic y;
+  core::num* a = math::max<core::num*>(x, y as{TypeError,ForDynamic} core::num*);
+  core::Object* b = math::max<core::num*>(x, y as{TypeError,ForDynamic} core::num*);
+  dynamic c = math::max<dynamic>(x, y);
+  dynamic d = math::max<dynamic>(x, y);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/downward_inference_miscellaneous.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downward_inference_miscellaneous.dart.weak.modular.expect
new file mode 100644
index 0000000..9ecd2a9
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downward_inference_miscellaneous.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef Function2<contravariant S extends core::Object* = dynamic, T extends core::Object* = dynamic> = (S*) →* T*;
+class A<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field (self::A::T*) →* self::A::T* x;
+  constructor •((self::A::T*) →* self::A::T* x) → self::A<self::A::T*>*
+    : self::A::x = x, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {
+  {
+    core::String* x = "hello";
+    core::int* y = 3;
+    function f(core::List<core::Map<core::int*, core::String*>*>* l) → void {}
+    ;
+    f(<core::Map<core::int*, core::String*>*>[<core::int*, core::String*>{y: x}]){(core::List<core::Map<core::int*, core::String*>*>*) →* void};
+  }
+  {
+    function f(core::int* x) → core::int*
+      return 0;
+    self::A<core::int*>* a = new self::A::•<core::int*>(f);
+  }
+}
diff --git a/pkg/front_end/testcases/inference/downwards_context_from_inferred_field_type.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_context_from_inferred_field_type.dart.weak.modular.expect
new file mode 100644
index 0000000..350439b
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_context_from_inferred_field_type.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract get foo() → core::Iterable<core::String*>*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::A {
+  final field core::Iterable<core::String*>* foo = #C1;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {}
+
+constants  {
+  #C1 = <core::String*>[]
+}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_annotations.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_annotations.dart.weak.modular.expect
new file mode 100644
index 0000000..5fdfe4d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_annotations.dart.weak.modular.expect
@@ -0,0 +1,66 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  const constructor •(core::List<core::String*>* l) → self::Foo*
+    : super core::Object::•()
+    ;
+  const constructor named(core::List<core::String*>* l) → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+@#C1
+class Bar extends core::Object {
+  synthetic constructor •() → self::Bar*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+@#C1
+class Baz extends core::Object {
+  synthetic constructor •() → self::Baz*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Foo {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///downwards_inference_annotations.dart:
+- Foo. (from org-dartlang-testcase:///downwards_inference_annotations.dart:9:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Foo.named (from org-dartlang-testcase:///downwards_inference_annotations.dart:10:9)
diff --git a/pkg/front_end/testcases/inference/downwards_inference_annotations_class_members.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_annotations_class_members.dart.weak.modular.expect
new file mode 100644
index 0000000..bc1bc95
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_annotations_class_members.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  const constructor •(core::List<core::String*>* l) → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Bar extends core::Object {
+  @#C1
+  field dynamic x = null;
+  @#C1
+  constructor •() → self::Bar*
+    : super core::Object::•()
+    ;
+  @#C1
+  abstract method f() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Foo {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///downwards_inference_annotations_class_members.dart:
+- Foo. (from org-dartlang-testcase:///downwards_inference_annotations_class_members.dart:9:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/inference/downwards_inference_annotations_for_loop_variable.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_annotations_for_loop_variable.dart.weak.modular.expect
new file mode 100644
index 0000000..c56e8ad
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_annotations_for_loop_variable.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  const constructor •(core::List<core::String*>* l) → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → void {
+  for (@#C1 core::int* i = 0; i.{core::num::<}(1){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+  }
+  for (@#C1 core::int* i in <core::int*>[0]) {
+  }
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Foo {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///downwards_inference_annotations_for_loop_variable.dart:
+- Foo. (from org-dartlang-testcase:///downwards_inference_annotations_for_loop_variable.dart:9:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/inference/downwards_inference_annotations_locals.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_annotations_locals.dart.weak.modular.expect
new file mode 100644
index 0000000..bd79165
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_annotations_locals.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  const constructor •(core::List<core::String*>* l) → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → void {
+  @#C1 dynamic x;
+  @#C1
+  function f() → void {}
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Foo {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///downwards_inference_annotations_locals.dart:
+- Foo. (from org-dartlang-testcase:///downwards_inference_annotations_locals.dart:9:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/inference/downwards_inference_annotations_locals_referring_to_locals.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_annotations_locals_referring_to_locals.dart.weak.modular.expect
new file mode 100644
index 0000000..4f025f27
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_annotations_locals_referring_to_locals.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  const constructor •(dynamic l) → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → void {
+  @#C1 dynamic y;
+  @#C1
+  function bar() → void {}
+  function baz(@#C1 dynamic formal) → void {}
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Foo {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///downwards_inference_annotations_locals_referring_to_locals.dart:
+- Foo. (from org-dartlang-testcase:///downwards_inference_annotations_locals_referring_to_locals.dart:9:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/inference/downwards_inference_annotations_parameter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_annotations_parameter.dart.weak.modular.expect
new file mode 100644
index 0000000..d7a402b
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_annotations_parameter.dart.weak.modular.expect
@@ -0,0 +1,47 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  const constructor •(core::List<core::String*>* l) → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method m(@#C1 dynamic x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f(@#C1 dynamic x) → void {}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Foo {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///downwards_inference_annotations_parameter.dart:
+- Foo. (from org-dartlang-testcase:///downwards_inference_annotations_parameter.dart:9:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/inference/downwards_inference_annotations_parameter_local.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_annotations_parameter_local.dart.weak.modular.expect
new file mode 100644
index 0000000..b72210d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_annotations_parameter_local.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  const constructor •(core::List<core::String*>* l) → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → void {
+  function f(@#C1 dynamic x) → void {}
+  (dynamic) →* Null x = (@#C1 dynamic x) → Null {};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Foo {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///downwards_inference_annotations_parameter_local.dart:
+- Foo. (from org-dartlang-testcase:///downwards_inference_annotations_parameter_local.dart:9:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/inference/downwards_inference_annotations_type_variable.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_annotations_type_variable.dart.weak.modular.expect
new file mode 100644
index 0000000..60436b4
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_annotations_type_variable.dart.weak.modular.expect
@@ -0,0 +1,63 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<@#C1 unrelated T extends core::Object* = dynamic> = () →* void;
+class Foo extends core::Object /*hasConstConstructor*/  {
+  const constructor •(core::List<core::String*>* l) → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<@#C1 T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  method m<@#C1 T extends core::Object* = dynamic>() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<@#C1 T extends core::Object* = dynamic>() → void {}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Foo {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///downwards_inference_annotations_type_variable.dart:
+- Foo. (from org-dartlang-testcase:///downwards_inference_annotations_type_variable.dart:9:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/inference/downwards_inference_annotations_type_variable_local.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_annotations_type_variable_local.dart.weak.modular.expect
new file mode 100644
index 0000000..59529f1
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_annotations_type_variable_local.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object /*hasConstConstructor*/  {
+  const constructor •(core::List<core::String*>* l) → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → void {
+  function f<@#C1 T extends core::Object* = dynamic>() → void {}
+  <T extends core::Object* = dynamic>() →* Null x = <@#C1 T extends core::Object* = dynamic>() → Null {};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Foo {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///downwards_inference_annotations_type_variable_local.dart:
+- Foo. (from org-dartlang-testcase:///downwards_inference_annotations_type_variable_local.dart:9:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/inference/downwards_inference_annotations_typedef.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_annotations_typedef.dart.weak.modular.expect
new file mode 100644
index 0000000..17384f4
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_annotations_typedef.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+@#C1
+typedef F = () →* void;
+class Foo extends core::Object /*hasConstConstructor*/  {
+  const constructor •(core::List<core::String*>* l) → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Foo {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///downwards_inference_annotations_typedef.dart:
+- Foo. (from org-dartlang-testcase:///downwards_inference_annotations_typedef.dart:9:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/inference/downwards_inference_assignment_statements.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_assignment_statements.dart.weak.modular.expect
new file mode 100644
index 0000000..c16d9c4
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_assignment_statements.dart.weak.modular.expect
@@ -0,0 +1,19 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/downwards_inference_assignment_statements.dart:10:72: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   l = /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"];
+//                                                                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  core::List<core::int*>* l;
+  l = <core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_assignment_statements.dart:10:72: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  l = /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"];
+                                                                       ^" in "hello" as{TypeError} core::int*];
+  l = l = <core::int*>[1];
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_async_await.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_async_await.dart.weak.modular.expect
new file mode 100644
index 0000000..1a5ac1a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_async_await.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library test;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "dart:async";
+
+static method main() → asy::Future<dynamic>* async {
+  dynamic d;
+  core::List<core::int*>* l0 = await<core::int*>[d as{TypeError,ForDynamic} core::int*];
+  core::List<core::int*>* l1 = await asy::Future::value<core::List<core::int*>*>(<core::int*>[d as{TypeError,ForDynamic} core::int*]);
+}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_for_each.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_for_each.dart.weak.modular.expect
new file mode 100644
index 0000000..e2d0f6d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_for_each.dart.weak.modular.expect
@@ -0,0 +1,105 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+abstract class MyStream<T extends core::Object* = dynamic> extends asy::Stream<self::MyStream::T*> {
+  static factory •<T extends core::Object* = dynamic>() → self::MyStream<self::MyStream::•::T*>*
+    return null;
+  abstract member-signature get isBroadcast() → core::bool*; -> asy::Stream::isBroadcast
+  abstract member-signature method asBroadcastStream({(asy::StreamSubscription<self::MyStream::T*>*) →* void onListen = #C1, (asy::StreamSubscription<self::MyStream::T*>*) →* void onCancel = #C1}) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::asBroadcastStream
+  abstract member-signature method where((self::MyStream::T*) →* core::bool* test) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::where
+  abstract member-signature method map<S extends core::Object* = dynamic>((self::MyStream::T*) →* self::MyStream::map::S* convert) → asy::Stream<self::MyStream::map::S*>*; -> asy::Stream::map
+  abstract member-signature method asyncMap<E extends core::Object* = dynamic>((self::MyStream::T*) →* FutureOr<self::MyStream::asyncMap::E*>* convert) → asy::Stream<self::MyStream::asyncMap::E*>*; -> asy::Stream::asyncMap
+  abstract member-signature method asyncExpand<E extends core::Object* = dynamic>((self::MyStream::T*) →* asy::Stream<self::MyStream::asyncExpand::E*>* convert) → asy::Stream<self::MyStream::asyncExpand::E*>*; -> asy::Stream::asyncExpand
+  abstract member-signature method handleError(core::Function* onError, {(dynamic) →* core::bool* test = #C1}) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::handleError
+  abstract member-signature method expand<S extends core::Object* = dynamic>((self::MyStream::T*) →* core::Iterable<self::MyStream::expand::S*>* convert) → asy::Stream<self::MyStream::expand::S*>*; -> asy::Stream::expand
+  abstract member-signature method pipe(covariant-by-class asy::StreamConsumer<self::MyStream::T*>* streamConsumer) → asy::Future<dynamic>*; -> asy::Stream::pipe
+  abstract member-signature method transform<S extends core::Object* = dynamic>(covariant-by-class asy::StreamTransformer<self::MyStream::T*, self::MyStream::transform::S*>* streamTransformer) → asy::Stream<self::MyStream::transform::S*>*; -> asy::Stream::transform
+  abstract member-signature method reduce(covariant-by-class (self::MyStream::T*, self::MyStream::T*) →* self::MyStream::T* combine) → asy::Future<self::MyStream::T*>*; -> asy::Stream::reduce
+  abstract member-signature method fold<S extends core::Object* = dynamic>(self::MyStream::fold::S* initialValue, (self::MyStream::fold::S*, self::MyStream::T*) →* self::MyStream::fold::S* combine) → asy::Future<self::MyStream::fold::S*>*; -> asy::Stream::fold
+  abstract member-signature method join([core::String* separator = #C2]) → asy::Future<core::String*>*; -> asy::Stream::join
+  abstract member-signature method contains(core::Object* needle) → asy::Future<core::bool*>*; -> asy::Stream::contains
+  abstract member-signature method forEach((self::MyStream::T*) →* void action) → asy::Future<dynamic>*; -> asy::Stream::forEach
+  abstract member-signature method every((self::MyStream::T*) →* core::bool* test) → asy::Future<core::bool*>*; -> asy::Stream::every
+  abstract member-signature method any((self::MyStream::T*) →* core::bool* test) → asy::Future<core::bool*>*; -> asy::Stream::any
+  abstract member-signature get length() → asy::Future<core::int*>*; -> asy::Stream::length
+  abstract member-signature get isEmpty() → asy::Future<core::bool*>*; -> asy::Stream::isEmpty
+  abstract member-signature method cast<R extends core::Object* = dynamic>() → asy::Stream<self::MyStream::cast::R*>*; -> asy::Stream::cast
+  abstract member-signature method toList() → asy::Future<core::List<self::MyStream::T*>*>*; -> asy::Stream::toList
+  abstract member-signature method toSet() → asy::Future<core::Set<self::MyStream::T*>*>*; -> asy::Stream::toSet
+  abstract member-signature method drain<E extends core::Object* = dynamic>([self::MyStream::drain::E* futureValue = #C1]) → asy::Future<self::MyStream::drain::E*>*; -> asy::Stream::drain
+  abstract member-signature method take(core::int* count) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::take
+  abstract member-signature method takeWhile((self::MyStream::T*) →* core::bool* test) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::takeWhile
+  abstract member-signature method skip(core::int* count) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::skip
+  abstract member-signature method skipWhile((self::MyStream::T*) →* core::bool* test) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::skipWhile
+  abstract member-signature method distinct([(self::MyStream::T*, self::MyStream::T*) →* core::bool* equals = #C1]) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::distinct
+  abstract member-signature get first() → asy::Future<self::MyStream::T*>*; -> asy::Stream::first
+  abstract member-signature get last() → asy::Future<self::MyStream::T*>*; -> asy::Stream::last
+  abstract member-signature get single() → asy::Future<self::MyStream::T*>*; -> asy::Stream::single
+  abstract member-signature method firstWhere((self::MyStream::T*) →* core::bool* test, {covariant-by-class () →* self::MyStream::T* orElse = #C1}) → asy::Future<self::MyStream::T*>*; -> asy::Stream::firstWhere
+  abstract member-signature method lastWhere((self::MyStream::T*) →* core::bool* test, {covariant-by-class () →* self::MyStream::T* orElse = #C1}) → asy::Future<self::MyStream::T*>*; -> asy::Stream::lastWhere
+  abstract member-signature method singleWhere((self::MyStream::T*) →* core::bool* test, {covariant-by-class () →* self::MyStream::T* orElse = #C1}) → asy::Future<self::MyStream::T*>*; -> asy::Stream::singleWhere
+  abstract member-signature method elementAt(core::int* index) → asy::Future<self::MyStream::T*>*; -> asy::Stream::elementAt
+  abstract member-signature method timeout(core::Duration* timeLimit, {(asy::EventSink<self::MyStream::T*>*) →* void onTimeout = #C1}) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::timeout
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature method listen((self::MyStream::T*) →* void onData, {core::Function* onError = #C1, () →* void onDone = #C1, core::bool* cancelOnError = #C1}) → asy::StreamSubscription<self::MyStream::T*>*; -> asy::Stream::listen
+}
+static method F<T extends core::Object* = dynamic>() → self::F::T*
+  return null;
+static method f() → asy::Future<dynamic>* async {
+  dynamic d;
+  core::Object* o;
+  for (dynamic x in self::F<core::Iterable<dynamic>*>()) {
+  }
+  for (dynamic x in self::F<core::Iterable<dynamic>*>()) {
+  }
+  for (core::Object* x in self::F<core::Iterable<core::Object*>*>()) {
+  }
+  for (final dynamic #t1 in self::F<core::Iterable<dynamic>*>()) {
+    d = #t1;
+  }
+  for (final core::Object* #t2 in self::F<core::Iterable<core::Object*>*>()) {
+    o = #t2;
+  }
+  await for (dynamic x in self::F<asy::Stream<dynamic>*>()) {
+  }
+  await for (dynamic x in self::F<asy::Stream<dynamic>*>()) {
+  }
+  await for (core::Object* x in self::F<asy::Stream<core::Object*>*>()) {
+  }
+  await for (final dynamic #t3 in self::F<asy::Stream<dynamic>*>()) {
+    d = #t3;
+  }
+  await for (final core::Object* #t4 in self::F<asy::Stream<core::Object*>*>()) {
+    o = #t4;
+  }
+}
+static method main() → asy::Future<dynamic>* async {
+  for (core::int* x in <core::int*>[1, 2, 3]) {
+  }
+  for (core::num* x in <core::num*>[1, 2, 3]) {
+  }
+  for (core::int* x in <core::int*>[1, 2, 3]) {
+  }
+  await for (core::int* x in self::MyStream::•<core::int*>()) {
+  }
+  await for (core::int* x in self::MyStream::•<core::int*>()) {
+  }
+}
+
+constants  {
+  #C1 = null
+  #C2 = ""
+}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_initializing_formal_default_formal.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_initializing_formal_default_formal.dart.weak.modular.expect
new file mode 100644
index 0000000..1283bb2
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_initializing_formal_default_formal.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef Function2<contravariant S extends core::Object* = dynamic, T extends core::Object* = dynamic> = ([S*]) →* T*;
+class Foo extends core::Object {
+  field core::List<core::int*>* x;
+  constructor •([core::List<core::int*>* x = #C2]) → self::Foo*
+    : self::Foo::x = x, super core::Object::•()
+    ;
+  constructor named([core::List<core::int*>* x = #C2]) → self::Foo*
+    : self::Foo::x = null, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field ([core::List<core::int*>*]) →* core::String* g = ([core::List<core::int*>* llll = #C2]) → core::String* => "hello";
+static method f([core::List<core::int*>* l = #C2]) → void {}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 1
+  #C2 = <core::int*>[#C1]
+}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_initializing_formal_default_formal.dart.weak.outline.expect b/pkg/front_end/testcases/inference/downwards_inference_initializing_formal_default_formal.dart.weak.outline.expect
index 2f2896d..91466e9 100644
--- a/pkg/front_end/testcases/inference/downwards_inference_initializing_formal_default_formal.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/inference/downwards_inference_initializing_formal_default_formal.dart.weak.outline.expect
@@ -5,9 +5,9 @@
 typedef Function2<contravariant S extends core::Object* = dynamic, T extends core::Object* = dynamic> = ([S*]) →* T*;
 class Foo extends core::Object {
   field core::List<core::int*>* x;
-  constructor •([core::List<core::int*>* x]) → self::Foo*
+  constructor •([core::List<core::int*>* x = const <core::int*>[1]]) → self::Foo*
     ;
-  constructor named([core::List<core::int*>* x]) → self::Foo*
+  constructor named([core::List<core::int*>* x = const <core::int*>[1]]) → self::Foo*
     ;
   abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
   abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
@@ -25,3 +25,9 @@
   ;
 static method main() → dynamic
   ;
+
+
+Extra constant evaluation status:
+Evaluated: ListLiteral @ org-dartlang-testcase:///downwards_inference_initializing_formal_default_formal.dart:12:38 -> ListConstant(const <int*>[1])
+Evaluated: ListLiteral @ org-dartlang-testcase:///downwards_inference_initializing_formal_default_formal.dart:13:49 -> ListConstant(const <int*>[1])
+Extra constant evaluation: evaluated: 2, effectively constant: 2
diff --git a/pkg/front_end/testcases/inference/downwards_inference_inside_top_level.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_inside_top_level.dart.weak.modular.expect
new file mode 100644
index 0000000..c66599a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_inside_top_level.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field self::B<core::int*>* b = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(self::B::T* x) → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::A* t1 = let final self::A* #t1 = new self::A::•() in block {
+  #t1.{self::A::b} = new self::B::•<core::int*>(1);
+} =>#t1;
+static field core::List<self::B<core::int*>*>* t2 = <self::B<core::int*>*>[new self::B::•<core::int*>(2)];
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_inside_top_level_2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_inside_top_level_2.dart.weak.modular.expect
new file mode 100644
index 0000000..69f8074
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_inside_top_level_2.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(self::A::T* x) → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::List<self::A<core::int*>*>* t1 = <self::A<core::int*>*>[new self::A::•<core::int*>(1)];
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart.weak.modular.expect
new file mode 100644
index 0000000..3550c19
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart.weak.modular.expect
@@ -0,0 +1,164 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:32:72: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"]);
+//                                                                        ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:34:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello",
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:41:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:44:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello",
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:51:72: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"]);
+//                                                                        ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:53:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello",
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:62:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"]
+//                                                                      ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:65:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"],
+//                                                                      ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:74:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"]
+//                                                                      ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:77:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"],
+//                                                                      ^
+//
+import self as self;
+import "dart:core" as core;
+
+class F0 extends core::Object {
+  constructor •(core::List<core::int*>* a) → self::F0*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F1 extends core::Object {
+  constructor •({core::List<core::int*>* a = #C1}) → self::F1*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F2 extends core::Object {
+  constructor •(core::Iterable<core::int*>* a) → self::F2*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F3 extends core::Object {
+  constructor •(core::Iterable<core::Iterable<core::int*>*>* a) → self::F3*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F4 extends core::Object {
+  constructor •({core::Iterable<core::Iterable<core::int*>*>* a = #C1}) → self::F4*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → void {
+  new self::F0::•(<core::int*>[]);
+  new self::F0::•(<core::int*>[3]);
+  new self::F0::•(<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:32:72: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"]);
+                                                                       ^" in "hello" as{TypeError} core::int*]);
+  new self::F0::•(<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:34:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\",
+                                               ^" in "hello" as{TypeError} core::int*, 3]);
+  new self::F1::•(a: <core::int*>[]);
+  new self::F1::•(a: <core::int*>[3]);
+  new self::F1::•(a: <core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:41:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"
+                                               ^" in "hello" as{TypeError} core::int*]);
+  new self::F1::•(a: <core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:44:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\",
+                                               ^" in "hello" as{TypeError} core::int*, 3]);
+  new self::F2::•(<core::int*>[]);
+  new self::F2::•(<core::int*>[3]);
+  new self::F2::•(<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:51:72: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"]);
+                                                                       ^" in "hello" as{TypeError} core::int*]);
+  new self::F2::•(<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:53:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\",
+                                               ^" in "hello" as{TypeError} core::int*, 3]);
+  new self::F3::•(<core::Iterable<core::int*>*>[]);
+  new self::F3::•(<core::Iterable<core::int*>*>[<core::int*>[3]]);
+  new self::F3::•(<core::Iterable<core::int*>*>[<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:62:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"]
+                                                                     ^" in "hello" as{TypeError} core::int*]]);
+  new self::F3::•(<core::Iterable<core::int*>*>[<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:65:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"],
+                                                                     ^" in "hello" as{TypeError} core::int*], <core::int*>[3]]);
+  new self::F4::•(a: <core::Iterable<core::int*>*>[]);
+  new self::F4::•(a: <core::Iterable<core::int*>*>[<core::int*>[3]]);
+  new self::F4::•(a: <core::Iterable<core::int*>*>[<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:74:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"]
+                                                                     ^" in "hello" as{TypeError} core::int*]]);
+  new self::F4::•(a: <core::Iterable<core::int*>*>[<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_constructor_arguments_infer_downwards.dart:77:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"],
+                                                                     ^" in "hello" as{TypeError} core::int*], <core::int*>[3]]);
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart.weak.modular.expect
new file mode 100644
index 0000000..5fd719d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart.weak.modular.expect
@@ -0,0 +1,99 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:16:71: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   f0(/*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"]);
+//                                                                       ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:17:71: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   f0(/*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello", 3]);
+//                                                                       ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:21:74: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   f1(a: /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"]);
+//                                                                          ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:23:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello",
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:29:71: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   f2(/*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"]);
+//                                                                       ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:30:71: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   f2(/*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello", 3]);
+//                                                                       ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:37:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"]
+//                                                                      ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:40:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"],
+//                                                                      ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:49:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"]
+//                                                                      ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:52:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"],
+//                                                                      ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method f0(core::List<core::int*>* a) → void {}
+static method f1({core::List<core::int*>* a = #C1}) → void {}
+static method f2(core::Iterable<core::int*>* a) → void {}
+static method f3(core::Iterable<core::Iterable<core::int*>*>* a) → void {}
+static method f4({core::Iterable<core::Iterable<core::int*>*>* a = #C1}) → void {}
+static method test() → void {
+  self::f0(<core::int*>[]);
+  self::f0(<core::int*>[3]);
+  self::f0(<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:16:71: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  f0(/*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"]);
+                                                                      ^" in "hello" as{TypeError} core::int*]);
+  self::f0(<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:17:71: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  f0(/*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\", 3]);
+                                                                      ^" in "hello" as{TypeError} core::int*, 3]);
+  self::f1(a: <core::int*>[]);
+  self::f1(a: <core::int*>[3]);
+  self::f1(a: <core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:21:74: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  f1(a: /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"]);
+                                                                         ^" in "hello" as{TypeError} core::int*]);
+  self::f1(a: <core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:23:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\",
+                                               ^" in "hello" as{TypeError} core::int*, 3]);
+  self::f2(<core::int*>[]);
+  self::f2(<core::int*>[3]);
+  self::f2(<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:29:71: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  f2(/*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"]);
+                                                                      ^" in "hello" as{TypeError} core::int*]);
+  self::f2(<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:30:71: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  f2(/*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\", 3]);
+                                                                      ^" in "hello" as{TypeError} core::int*, 3]);
+  self::f3(<core::Iterable<core::int*>*>[]);
+  self::f3(<core::Iterable<core::int*>*>[<core::int*>[3]]);
+  self::f3(<core::Iterable<core::int*>*>[<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:37:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"]
+                                                                     ^" in "hello" as{TypeError} core::int*]]);
+  self::f3(<core::Iterable<core::int*>*>[<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:40:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"],
+                                                                     ^" in "hello" as{TypeError} core::int*], <core::int*>[3]]);
+  self::f4(a: <core::Iterable<core::int*>*>[]);
+  self::f4(a: <core::Iterable<core::int*>*>[<core::int*>[3]]);
+  self::f4(a: <core::Iterable<core::int*>*>[<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:49:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"]
+                                                                     ^" in "hello" as{TypeError} core::int*]]);
+  self::f4(a: <core::Iterable<core::int*>*>[<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_arguments_infer_downwards.dart:52:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"],
+                                                                     ^" in "hello" as{TypeError} core::int*], <core::int*>[3]]);
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart.weak.modular.expect
new file mode 100644
index 0000000..f4f3e7f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart.weak.modular.expect
@@ -0,0 +1,117 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:15:69: Error: A value of type 'String Function(String)' can't be assigned to a variable of type 'String Function(int)'.
+//         l2 = /*error:INVALID_ASSIGNMENT*/ /*@ returnType=String* */ (String x) =>
+//                                                                     ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:18:80: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//         l3 = /*error:INVALID_ASSIGNMENT*/ /*@ returnType=String* */ (int x) => 3;
+//                                                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:20:47: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//       return /*error:RETURN_OF_INVALID_TYPE*/ 3;
+//                                               ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:29:13: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//             3;
+//             ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:31:47: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//       return /*error:RETURN_OF_INVALID_TYPE*/ 3;
+//                                               ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:34:47: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//       return /*error:RETURN_OF_INVALID_TYPE*/ x;
+//                                               ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:42:76: Error: A value of type 'List<String> Function(String)' can't be assigned to a variable of type 'List<String> Function(int)'.
+//  - 'List' is from 'dart:core'.
+//         l2 = /*error:INVALID_ASSIGNMENT*/ /*@ returnType=List<String*>* */ (String
+//                                                                            ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:46:58: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//               /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ 3
+//                                                          ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:50:52: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//         /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ 3
+//                                                    ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:60:13: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//             x;
+//             ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:63:14: Error: The method 'substring' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing method, or defining a method named 'substring'.
+//             .substring(3);
+//              ^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef Function2<contravariant S extends core::Object* = dynamic, T extends core::Object* = dynamic> = (S*) →* T*;
+static method test() → void {
+  {
+    (core::int*) →* core::String* l0 = (core::int* x) → Null => null;
+    (core::int*) →* core::String* l1 = (core::int* x) → core::String* => "hello";
+    (core::int*) →* core::String* l2 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:15:69: Error: A value of type 'String Function(String)' can't be assigned to a variable of type 'String Function(int)'.
+        l2 = /*error:INVALID_ASSIGNMENT*/ /*@ returnType=String* */ (String x) =>
+                                                                    ^" in ((core::String* x) → core::String* => "hello") as{TypeError} (core::int*) →* core::String*;
+    (core::int*) →* core::String* l3 = (core::int* x) → core::String* => invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:18:80: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+        l3 = /*error:INVALID_ASSIGNMENT*/ /*@ returnType=String* */ (int x) => 3;
+                                                                               ^" in 3 as{TypeError} core::String*;
+    (core::int*) →* core::String* l4 = (core::int* x) → core::String* {
+      return invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:20:47: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+      return /*error:RETURN_OF_INVALID_TYPE*/ 3;
+                                              ^" in 3 as{TypeError} core::String*;
+    };
+  }
+  {
+    (core::int*) →* core::String* l0 = (core::int* x) → Null => null;
+    (core::int*) →* core::String* l1 = (core::int* x) → core::String* => "hello";
+    (core::int*) →* core::String* l2 = (core::int* x) → core::String* => invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:29:13: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+            3;
+            ^" in 3 as{TypeError} core::String*;
+    (core::int*) →* core::String* l3 = (core::int* x) → core::String* {
+      return invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:31:47: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+      return /*error:RETURN_OF_INVALID_TYPE*/ 3;
+                                              ^" in 3 as{TypeError} core::String*;
+    };
+    (core::int*) →* core::String* l4 = (core::int* x) → core::String* {
+      return invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:34:47: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+      return /*error:RETURN_OF_INVALID_TYPE*/ x;
+                                              ^" in x as{TypeError} core::String*;
+    };
+  }
+  {
+    (core::int*) →* core::List<core::String*>* l0 = (core::int* x) → Null => null;
+    (core::int*) →* core::List<core::String*>* l1 = (core::int* x) → core::List<core::String*>* => <core::String*>["hello"];
+    (core::int*) →* core::List<core::String*>* l2 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:42:76: Error: A value of type 'List<String> Function(String)' can't be assigned to a variable of type 'List<String> Function(int)'.
+ - 'List' is from 'dart:core'.
+        l2 = /*error:INVALID_ASSIGNMENT*/ /*@ returnType=List<String*>* */ (String
+                                                                           ^" in ((core::String* x) → core::List<core::String*>* => <core::String*>["hello"]) as{TypeError} (core::int*) →* core::List<core::String*>*;
+    (core::int*) →* core::List<core::String*>* l3 = (core::int* x) → core::List<core::String*>* => <core::String*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:46:58: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+              /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ 3
+                                                         ^" in 3 as{TypeError} core::String*];
+    (core::int*) →* core::List<core::String*>* l4 = (core::int* x) → core::List<core::String*>* {
+      return <core::String*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:50:52: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+        /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ 3
+                                                   ^" in 3 as{TypeError} core::String*];
+    };
+  }
+  {
+    (core::int*) →* core::int* l0 = (core::int* x) → core::int* => x;
+    (core::int*) →* core::int* l1 = (core::int* x) → core::int* => x.{core::num::+}(1){(core::num*) →* core::int*};
+    (core::int*) →* core::String* l2 = (core::int* x) → core::String* => invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:60:13: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+            x;
+            ^" in x as{TypeError} core::String*;
+    (core::int*) →* core::String* l3 = (core::int* x) → core::String* => invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_function_expressions.dart:63:14: Error: The method 'substring' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing method, or defining a method named 'substring'.
+            .substring(3);
+             ^^^^^^^^^" in x{<unresolved>}.substring(3) as{TypeError,ForDynamic} core::String*;
+    (core::String*) →* core::String* l4 = (core::String* x) → core::String* => x.{core::String::substring}(3){(core::int*, [core::int*]) →* core::String*};
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_on_function_of_t_using_the_t.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_on_function_of_t_using_the_t.dart.weak.modular.expect
new file mode 100644
index 0000000..a686107
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_on_function_of_t_using_the_t.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → void {
+  {
+    function f<T extends core::Object* = dynamic>(T* x) → T*
+      return null;
+    <T extends core::Object* = dynamic>(T*) →* T* v1 = f;
+    v1 = <S extends core::Object* = dynamic>(S* x) → S* => x;
+  }
+  {
+    function f<T extends core::Object* = dynamic>(T* x) → core::List<T*>*
+      return null;
+    <T extends core::Object* = dynamic>(T*) →* core::List<T*>* v2 = f;
+    v2 = <S extends core::Object* = dynamic>(S* x) → core::List<S*>* => <S*>[x];
+    core::Iterable<core::int*>* r = v2<core::int*>(42){(core::int*) →* core::List<core::int*>*};
+    core::Iterable<core::String*>* s = v2<core::String*>("hello"){(core::String*) →* core::List<core::String*>*};
+    core::Iterable<core::List<core::int*>*>* t = v2<core::List<core::int*>*>(<core::int*>[]){(core::List<core::int*>*) →* core::List<core::List<core::int*>*>*};
+    core::Iterable<core::num*>* u = v2<core::num*>(42){(core::num*) →* core::List<core::num*>*};
+    core::Iterable<core::num*>* v = v2<core::num*>(42){(core::num*) →* core::List<core::num*>*};
+  }
+}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_empty_list.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_empty_list.dart.weak.modular.expect
new file mode 100644
index 0000000..81acf78
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_empty_list.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class F3<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(core::Iterable<core::Iterable<self::F3::T*>*>* a) → self::F3<self::F3::T*>*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F4<T extends core::Object* = dynamic> extends core::Object {
+  constructor •({core::Iterable<core::Iterable<self::F4::T*>*>* a = #C1}) → self::F4<self::F4::T*>*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {
+  new self::F3::•<dynamic>(<core::Iterable<dynamic>*>[]);
+  new self::F4::•<dynamic>(a: <core::Iterable<dynamic>*>[]);
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart.weak.modular.expect
new file mode 100644
index 0000000..6d35ee8
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart.weak.modular.expect
@@ -0,0 +1,172 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:32:72: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"]);
+//                                                                        ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:34:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello",
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:41:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:44:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello",
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:51:72: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"]);
+//                                                                        ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:53:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello",
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:62:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"]
+//                                                                      ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:65:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"],
+//                                                                      ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:74:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"]
+//                                                                      ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:77:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"],
+//                                                                      ^
+//
+import self as self;
+import "dart:core" as core;
+
+class F0<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(core::List<self::F0::T*>* a) → self::F0<self::F0::T*>*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F1<T extends core::Object* = dynamic> extends core::Object {
+  constructor •({core::List<self::F1::T*>* a = #C1}) → self::F1<self::F1::T*>*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F2<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(core::Iterable<self::F2::T*>* a) → self::F2<self::F2::T*>*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F3<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(core::Iterable<core::Iterable<self::F3::T*>*>* a) → self::F3<self::F3::T*>*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F4<T extends core::Object* = dynamic> extends core::Object {
+  constructor •({core::Iterable<core::Iterable<self::F4::T*>*>* a = #C1}) → self::F4<self::F4::T*>*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → void {
+  new self::F0::•<core::int*>(<core::int*>[]);
+  new self::F0::•<core::int*>(<core::int*>[3]);
+  new self::F0::•<core::int*>(<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:32:72: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"]);
+                                                                       ^" in "hello" as{TypeError} core::int*]);
+  new self::F0::•<core::int*>(<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:34:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\",
+                                               ^" in "hello" as{TypeError} core::int*, 3]);
+  new self::F1::•<core::int*>(a: <core::int*>[]);
+  new self::F1::•<core::int*>(a: <core::int*>[3]);
+  new self::F1::•<core::int*>(a: <core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:41:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"
+                                               ^" in "hello" as{TypeError} core::int*]);
+  new self::F1::•<core::int*>(a: <core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:44:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\",
+                                               ^" in "hello" as{TypeError} core::int*, 3]);
+  new self::F2::•<core::int*>(<core::int*>[]);
+  new self::F2::•<core::int*>(<core::int*>[3]);
+  new self::F2::•<core::int*>(<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:51:72: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"]);
+                                                                       ^" in "hello" as{TypeError} core::int*]);
+  new self::F2::•<core::int*>(<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:53:48: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\",
+                                               ^" in "hello" as{TypeError} core::int*, 3]);
+  new self::F3::•<core::int*>(<core::Iterable<core::int*>*>[]);
+  new self::F3::•<core::int*>(<core::Iterable<core::int*>*>[<core::int*>[3]]);
+  new self::F3::•<core::int*>(<core::Iterable<core::int*>*>[<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:62:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"]
+                                                                     ^" in "hello" as{TypeError} core::int*]]);
+  new self::F3::•<core::int*>(<core::Iterable<core::int*>*>[<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:65:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"],
+                                                                     ^" in "hello" as{TypeError} core::int*], <core::int*>[3]]);
+  new self::F4::•<core::int*>(a: <core::Iterable<core::int*>*>[]);
+  new self::F4::•<core::int*>(a: <core::Iterable<core::int*>*>[<core::int*>[3]]);
+  new self::F4::•<core::int*>(a: <core::Iterable<core::int*>*>[<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:74:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"]
+                                                                     ^" in "hello" as{TypeError} core::int*]]);
+  new self::F4::•<core::int*>(a: <core::Iterable<core::int*>*>[<core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_constructor_arguments_infer_downwards.dart:77:70: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    /*@ typeArgs=int* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"],
+                                                                     ^" in "hello" as{TypeError} core::int*], <core::int*>[3]]);
+  new self::F3::•<dynamic>(<core::Iterable<dynamic>*>[]);
+  self::F3<core::int*>* f31 = new self::F3::•<core::int*>(<core::List<core::int*>*>[<core::int*>[3]]);
+  self::F3<core::String*>* f32 = new self::F3::•<core::String*>(<core::List<core::String*>*>[<core::String*>["hello"]]);
+  self::F3<core::Object*>* f33 = new self::F3::•<core::Object*>(<core::List<core::Object*>*>[<core::String*>["hello"], <core::int*>[3]]);
+  new self::F4::•<dynamic>(a: <core::Iterable<dynamic>*>[]);
+  new self::F4::•<core::int*>(a: <core::List<core::int*>*>[<core::int*>[3]]);
+  new self::F4::•<core::String*>(a: <core::List<core::String*>*>[<core::String*>["hello"]]);
+  new self::F4::•<core::Object*>(a: <core::List<core::Object*>*>[<core::String*>["hello"], <core::int*>[3]]);
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart.weak.modular.expect
new file mode 100644
index 0000000..9dc00c4
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart.weak.modular.expect
@@ -0,0 +1,134 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:14:68: Error: A value of type 'String Function<T>(String)' can't be assigned to a variable of type 'String Function<S>(int)'.
+//     v = /*error:INVALID_ASSIGNMENT*/ <T> /*@ returnType=String* */ (String x) =>
+//                                                                    ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:16:79: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//     v = /*error:INVALID_ASSIGNMENT*/ <T> /*@ returnType=String* */ (int x) => 3;
+//                                                                               ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:18:47: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//       return /*error:RETURN_OF_INVALID_TYPE*/ 3;
+//                                               ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:28:9: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//         3;
+//         ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:30:47: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//       return /*error:RETURN_OF_INVALID_TYPE*/ 3;
+//                                               ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:33:47: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//       return /*error:RETURN_OF_INVALID_TYPE*/ x;
+//                                               ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:43:75: Error: A value of type 'List<String> Function<T>(String)' can't be assigned to a variable of type 'List<String> Function<S>(int)'.
+//  - 'List' is from 'dart:core'.
+//     v = /*error:INVALID_ASSIGNMENT*/ <T> /*@ returnType=List<String*>* */ (String
+//                                                                           ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:46:54: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//           /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ 3
+//                                                      ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:50:52: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//         /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ 3
+//                                                    ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:64:9: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//         x;
+//         ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:66:10: Error: The method 'substring' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing method, or defining a method named 'substring'.
+//         .substring(3);
+//          ^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  {
+    function f<S extends core::Object* = dynamic>(core::int* x) → core::String*
+      return null;
+    <S extends core::Object* = dynamic>(core::int*) →* core::String* v = f;
+    v = <T extends core::Object* = dynamic>(core::int* x) → Null => null;
+    v = <T extends core::Object* = dynamic>(core::int* x) → core::String* => "hello";
+    v = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:14:68: Error: A value of type 'String Function<T>(String)' can't be assigned to a variable of type 'String Function<S>(int)'.
+    v = /*error:INVALID_ASSIGNMENT*/ <T> /*@ returnType=String* */ (String x) =>
+                                                                   ^" in (<T extends core::Object* = dynamic>(core::String* x) → core::String* => "hello") as{TypeError} <S extends core::Object* = dynamic>(core::int*) →* core::String*;
+    v = <T extends core::Object* = dynamic>(core::int* x) → core::String* => invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:16:79: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+    v = /*error:INVALID_ASSIGNMENT*/ <T> /*@ returnType=String* */ (int x) => 3;
+                                                                              ^" in 3 as{TypeError} core::String*;
+    v = <T extends core::Object* = dynamic>(core::int* x) → core::String* {
+      return invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:18:47: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+      return /*error:RETURN_OF_INVALID_TYPE*/ 3;
+                                              ^" in 3 as{TypeError} core::String*;
+    };
+  }
+  {
+    function f<S extends core::Object* = dynamic>(core::int* x) → core::String*
+      return null;
+    <S extends core::Object* = dynamic>(core::int*) →* core::String* v = f;
+    v = <T extends core::Object* = dynamic>(core::int* x) → Null => null;
+    v = <T extends core::Object* = dynamic>(core::int* x) → core::String* => "hello";
+    v = <T extends core::Object* = dynamic>(core::int* x) → core::String* => invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:28:9: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+        3;
+        ^" in 3 as{TypeError} core::String*;
+    v = <T extends core::Object* = dynamic>(core::int* x) → core::String* {
+      return invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:30:47: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+      return /*error:RETURN_OF_INVALID_TYPE*/ 3;
+                                              ^" in 3 as{TypeError} core::String*;
+    };
+    v = <T extends core::Object* = dynamic>(core::int* x) → core::String* {
+      return invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:33:47: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+      return /*error:RETURN_OF_INVALID_TYPE*/ x;
+                                              ^" in x as{TypeError} core::String*;
+    };
+  }
+  {
+    function f<S extends core::Object* = dynamic>(core::int* x) → core::List<core::String*>*
+      return null;
+    <S extends core::Object* = dynamic>(core::int*) →* core::List<core::String*>* v = f;
+    v = <T extends core::Object* = dynamic>(core::int* x) → Null => null;
+    v = <T extends core::Object* = dynamic>(core::int* x) → core::List<core::String*>* => <core::String*>["hello"];
+    v = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:43:75: Error: A value of type 'List<String> Function<T>(String)' can't be assigned to a variable of type 'List<String> Function<S>(int)'.
+ - 'List' is from 'dart:core'.
+    v = /*error:INVALID_ASSIGNMENT*/ <T> /*@ returnType=List<String*>* */ (String
+                                                                          ^" in (<T extends core::Object* = dynamic>(core::String* x) → core::List<core::String*>* => <core::String*>["hello"]) as{TypeError} <S extends core::Object* = dynamic>(core::int*) →* core::List<core::String*>*;
+    v = <T extends core::Object* = dynamic>(core::int* x) → core::List<core::String*>* => <core::String*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:46:54: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+          /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ 3
+                                                     ^" in 3 as{TypeError} core::String*];
+    v = <T extends core::Object* = dynamic>(core::int* x) → core::List<core::String*>* {
+      return <core::String*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:50:52: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+        /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ 3
+                                                   ^" in 3 as{TypeError} core::String*];
+    };
+  }
+  {
+    function int2int<S extends core::Object* = dynamic>(core::int* x) → core::int*
+      return null;
+    function int2String<T extends core::Object* = dynamic>(core::int* x) → core::String*
+      return null;
+    function string2String<T extends core::Object* = dynamic>(core::String* x) → core::String*
+      return null;
+    <S extends core::Object* = dynamic>(core::int*) →* core::int* x = int2int;
+    x = <T extends core::Object* = dynamic>(core::int* x) → core::int* => x;
+    x = <T extends core::Object* = dynamic>(core::int* x) → core::int* => x.{core::num::+}(1){(core::num*) →* core::int*};
+    <T extends core::Object* = dynamic>(core::int*) →* core::String* y = int2String;
+    y = <T extends core::Object* = dynamic>(core::int* x) → core::String* => invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:64:9: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+        x;
+        ^" in x as{TypeError} core::String*;
+    y = <T extends core::Object* = dynamic>(core::int* x) → core::String* => invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_generic_function_expressions.dart:66:10: Error: The method 'substring' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing method, or defining a method named 'substring'.
+        .substring(3);
+         ^^^^^^^^^" in x{<unresolved>}.substring(3) as{TypeError,ForDynamic} core::String*;
+    <T extends core::Object* = dynamic>(core::String*) →* core::String* z = string2String;
+    z = <T extends core::Object* = dynamic>(core::String* x) → core::String* => x.{core::String::substring}(3){(core::int*, [core::int*]) →* core::String*};
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart.weak.modular.expect
new file mode 100644
index 0000000..ef65173
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart.weak.modular.expect
@@ -0,0 +1,312 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:46:50: Error: The constructor returns type 'A<int, dynamic>' that isn't of expected type 'A<int, String>'.
+//  - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+// Change the type of the object being constructed or the context in which it is used.
+//         a4 = /*error:INVALID_CAST_NEW_EXPR*/ new A<int, dynamic>(3, "hello");
+//                                                  ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:48:50: Error: The constructor returns type 'A<dynamic, dynamic>' that isn't of expected type 'A<int, String>'.
+//  - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+// Change the type of the object being constructed or the context in which it is used.
+//         a5 = /*error:INVALID_CAST_NEW_EXPR*/ new A<dynamic, dynamic>.named(
+//                                                  ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:53:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//         /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ "hello",
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:54:48: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+//         /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 3);
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:56:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//         /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ "hello",
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:57:48: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+//         /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 3);
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:65:47: Error: A value of type 'B<String, dynamic>' can't be assigned to a variable of type 'A<int, String>'.
+//  - 'B' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+//         a4 = /*error:INVALID_ASSIGNMENT*/ new B<String, dynamic>("hello", 3);
+//                                               ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:67:47: Error: A value of type 'B<dynamic, dynamic>' can't be assigned to a variable of type 'A<int, String>'.
+//  - 'B' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+//         a5 = /*error:INVALID_ASSIGNMENT*/ new B<dynamic, dynamic>.named(
+//                                               ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:72:48: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+//         /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 3,
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:73:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//         /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ "hello");
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:75:48: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+//         /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 3,
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:76:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//         /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ "hello");
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:83:55: Error: A value of type 'C<dynamic>' can't be assigned to a variable of type 'A<int, int>'.
+//  - 'C' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+//     A<int, int> a4 = /*error:INVALID_ASSIGNMENT*/ new C<dynamic>(3);
+//                                                       ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:84:55: Error: A value of type 'C<dynamic>' can't be assigned to a variable of type 'A<int, int>'.
+//  - 'C' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+//     A<int, int> a5 = /*error:INVALID_ASSIGNMENT*/ new C<dynamic>.named(3);
+//                                                       ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:88:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//         /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ "hello");
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:90:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//         /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ "hello");
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:98:47: Error: A value of type 'D<num, dynamic>' can't be assigned to a variable of type 'A<int, String>'.
+//  - 'D' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+//         a4 = /*error:INVALID_ASSIGNMENT*/ new D<num, dynamic>("hello");
+//                                               ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:100:47: Error: A value of type 'D<dynamic, dynamic>' can't be assigned to a variable of type 'A<int, String>'.
+//  - 'D' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+//         a5 = /*error:INVALID_ASSIGNMENT*/ new D<dynamic, dynamic>.named(
+//                                               ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:105:48: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+//         /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 3);
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:107:48: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+//         /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 3);
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:118:54: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//           /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"
+//                                                      ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:121:54: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//           /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ 3
+//                                                      ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:129:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//         /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ "hello",
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:130:48: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+//         /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 3);
+//                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:134:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//         /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ "hello");
+//                                                ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<S extends core::Object* = dynamic, T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::A::S* x;
+  covariant-by-class field self::A::T* y;
+  constructor •(self::A::S* x, self::A::T* y) → self::A<self::A::S*, self::A::T*>*
+    : self::A::x = x, self::A::y = y, super core::Object::•()
+    ;
+  constructor named(self::A::S* x, self::A::T* y) → self::A<self::A::S*, self::A::T*>*
+    : self::A::x = x, self::A::y = y, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<S extends core::Object* = dynamic, T extends core::Object* = dynamic> extends self::A<self::B::T*, self::B::S*> {
+  constructor •(self::B::S* y, self::B::T* x) → self::B<self::B::S*, self::B::T*>*
+    : super self::A::•(x, y)
+    ;
+  constructor named(self::B::S* y, self::B::T* x) → self::B<self::B::S*, self::B::T*>*
+    : super self::A::named(x, y)
+    ;
+}
+class C<S extends core::Object* = dynamic> extends self::B<self::C::S*, self::C::S*> {
+  constructor •(self::C::S* a) → self::C<self::C::S*>*
+    : super self::B::•(a, a)
+    ;
+  constructor named(self::C::S* a) → self::C<self::C::S*>*
+    : super self::B::named(a, a)
+    ;
+}
+class D<S extends core::Object* = dynamic, T extends core::Object* = dynamic> extends self::B<self::D::T*, core::int*> {
+  constructor •(self::D::T* a) → self::D<self::D::S*, self::D::T*>*
+    : super self::B::•(a, 3)
+    ;
+  constructor named(self::D::T* a) → self::D<self::D::S*, self::D::T*>*
+    : super self::B::named(a, 3)
+    ;
+}
+class E<S extends core::Object* = dynamic, T extends core::Object* = dynamic> extends self::A<self::C<self::E::S*>*, self::E::T*> {
+  constructor •(self::E::T* a) → self::E<self::E::S*, self::E::T*>*
+    : super self::A::•(null, a)
+    ;
+}
+class F<S extends core::Object* = dynamic, T extends core::Object* = dynamic> extends self::A<self::F::S*, self::F::T*> {
+  constructor •(self::F::S* x, self::F::T* y, {core::List<self::F::S*>* a = #C1, core::List<self::F::T*>* b = #C1}) → self::F<self::F::S*, self::F::T*>*
+    : super self::A::•(x, y)
+    ;
+  constructor named(self::F::S* x, self::F::T* y, [self::F::S* a = #C1, self::F::T* b = #C1]) → self::F<self::F::S*, self::F::T*>*
+    : super self::A::•(a, b)
+    ;
+}
+static method test() → void {
+  {
+    self::A<core::int*, core::String*>* a0 = new self::A::•<core::int*, core::String*>(3, "hello");
+    self::A<core::int*, core::String*>* a1 = new self::A::named<core::int*, core::String*>(3, "hello");
+    self::A<core::int*, core::String*>* a2 = new self::A::•<core::int*, core::String*>(3, "hello");
+    self::A<core::int*, core::String*>* a3 = new self::A::named<core::int*, core::String*>(3, "hello");
+    self::A<core::int*, core::String*>* a4 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:46:50: Error: The constructor returns type 'A<int, dynamic>' that isn't of expected type 'A<int, String>'.
+ - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+Change the type of the object being constructed or the context in which it is used.
+        a4 = /*error:INVALID_CAST_NEW_EXPR*/ new A<int, dynamic>(3, \"hello\");
+                                                 ^" in new self::A::•<core::int*, dynamic>(3, "hello");
+    self::A<core::int*, core::String*>* a5 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:48:50: Error: The constructor returns type 'A<dynamic, dynamic>' that isn't of expected type 'A<int, String>'.
+ - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+Change the type of the object being constructed or the context in which it is used.
+        a5 = /*error:INVALID_CAST_NEW_EXPR*/ new A<dynamic, dynamic>.named(
+                                                 ^" in new self::A::named<dynamic, dynamic>(3, "hello");
+  }
+  {
+    self::A<core::int*, core::String*>* a0 = new self::A::•<core::int*, core::String*>(invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:53:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+        /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\",
+                                               ^" in "hello" as{TypeError} core::int*, invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:54:48: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+        /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 3);
+                                               ^" in 3 as{TypeError} core::String*);
+    self::A<core::int*, core::String*>* a1 = new self::A::named<core::int*, core::String*>(invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:56:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+        /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\",
+                                               ^" in "hello" as{TypeError} core::int*, invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:57:48: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+        /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 3);
+                                               ^" in 3 as{TypeError} core::String*);
+  }
+  {
+    self::A<core::int*, core::String*>* a0 = new self::B::•<core::String*, core::int*>("hello", 3);
+    self::A<core::int*, core::String*>* a1 = new self::B::named<core::String*, core::int*>("hello", 3);
+    self::A<core::int*, core::String*>* a2 = new self::B::•<core::String*, core::int*>("hello", 3);
+    self::A<core::int*, core::String*>* a3 = new self::B::named<core::String*, core::int*>("hello", 3);
+    self::A<core::int*, core::String*>* a4 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:65:47: Error: A value of type 'B<String, dynamic>' can't be assigned to a variable of type 'A<int, String>'.
+ - 'B' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+ - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+        a4 = /*error:INVALID_ASSIGNMENT*/ new B<String, dynamic>(\"hello\", 3);
+                                              ^" in new self::B::•<core::String*, dynamic>("hello", 3) as{TypeError} self::A<core::int*, core::String*>*;
+    self::A<core::int*, core::String*>* a5 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:67:47: Error: A value of type 'B<dynamic, dynamic>' can't be assigned to a variable of type 'A<int, String>'.
+ - 'B' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+ - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+        a5 = /*error:INVALID_ASSIGNMENT*/ new B<dynamic, dynamic>.named(
+                                              ^" in new self::B::named<dynamic, dynamic>("hello", 3) as{TypeError} self::A<core::int*, core::String*>*;
+  }
+  {
+    self::A<core::int*, core::String*>* a0 = new self::B::•<core::String*, core::int*>(invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:72:48: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+        /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 3,
+                                               ^" in 3 as{TypeError} core::String*, invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:73:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+        /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\");
+                                               ^" in "hello" as{TypeError} core::int*);
+    self::A<core::int*, core::String*>* a1 = new self::B::named<core::String*, core::int*>(invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:75:48: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+        /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 3,
+                                               ^" in 3 as{TypeError} core::String*, invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:76:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+        /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\");
+                                               ^" in "hello" as{TypeError} core::int*);
+  }
+  {
+    self::A<core::int*, core::int*>* a0 = new self::C::•<core::int*>(3);
+    self::A<core::int*, core::int*>* a1 = new self::C::named<core::int*>(3);
+    self::A<core::int*, core::int*>* a2 = new self::C::•<core::int*>(3);
+    self::A<core::int*, core::int*>* a3 = new self::C::named<core::int*>(3);
+    self::A<core::int*, core::int*>* a4 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:83:55: Error: A value of type 'C<dynamic>' can't be assigned to a variable of type 'A<int, int>'.
+ - 'C' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+ - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+    A<int, int> a4 = /*error:INVALID_ASSIGNMENT*/ new C<dynamic>(3);
+                                                      ^" in new self::C::•<dynamic>(3) as{TypeError} self::A<core::int*, core::int*>*;
+    self::A<core::int*, core::int*>* a5 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:84:55: Error: A value of type 'C<dynamic>' can't be assigned to a variable of type 'A<int, int>'.
+ - 'C' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+ - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+    A<int, int> a5 = /*error:INVALID_ASSIGNMENT*/ new C<dynamic>.named(3);
+                                                      ^" in new self::C::named<dynamic>(3) as{TypeError} self::A<core::int*, core::int*>*;
+  }
+  {
+    self::A<core::int*, core::int*>* a0 = new self::C::•<core::int*>(invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:88:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+        /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\");
+                                               ^" in "hello" as{TypeError} core::int*);
+    self::A<core::int*, core::int*>* a1 = new self::C::named<core::int*>(invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:90:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+        /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\");
+                                               ^" in "hello" as{TypeError} core::int*);
+  }
+  {
+    self::A<core::int*, core::String*>* a0 = new self::D::•<dynamic, core::String*>("hello");
+    self::A<core::int*, core::String*>* a1 = new self::D::named<dynamic, core::String*>("hello");
+    self::A<core::int*, core::String*>* a2 = new self::D::•<core::int*, core::String*>("hello");
+    self::A<core::int*, core::String*>* a3 = new self::D::named<core::String*, core::String*>("hello");
+    self::A<core::int*, core::String*>* a4 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:98:47: Error: A value of type 'D<num, dynamic>' can't be assigned to a variable of type 'A<int, String>'.
+ - 'D' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+ - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+        a4 = /*error:INVALID_ASSIGNMENT*/ new D<num, dynamic>(\"hello\");
+                                              ^" in new self::D::•<core::num*, dynamic>("hello") as{TypeError} self::A<core::int*, core::String*>*;
+    self::A<core::int*, core::String*>* a5 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:100:47: Error: A value of type 'D<dynamic, dynamic>' can't be assigned to a variable of type 'A<int, String>'.
+ - 'D' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+ - 'A' is from 'pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart'.
+        a5 = /*error:INVALID_ASSIGNMENT*/ new D<dynamic, dynamic>.named(
+                                              ^" in new self::D::named<dynamic, dynamic>("hello") as{TypeError} self::A<core::int*, core::String*>*;
+  }
+  {
+    self::A<core::int*, core::String*>* a0 = new self::D::•<dynamic, core::String*>(invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:105:48: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+        /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 3);
+                                               ^" in 3 as{TypeError} core::String*);
+    self::A<core::int*, core::String*>* a1 = new self::D::named<dynamic, core::String*>(invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:107:48: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+        /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 3);
+                                               ^" in 3 as{TypeError} core::String*);
+  }
+  {
+    self::A<self::C<core::int*>*, core::String*>* a0 = new self::E::•<core::int*, core::String*>("hello");
+  }
+  {
+    self::A<core::int*, core::String*>* a0 = new self::F::•<core::int*, core::String*>(3, "hello", a: <core::int*>[3], b: <core::String*>["hello"]);
+    self::A<core::int*, core::String*>* a1 = new self::F::•<core::int*, core::String*>(3, "hello", a: <core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:118:54: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+          /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"
+                                                     ^" in "hello" as{TypeError} core::int*], b: <core::String*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:121:54: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+          /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ 3
+                                                     ^" in 3 as{TypeError} core::String*]);
+    self::A<core::int*, core::String*>* a2 = new self::F::named<core::int*, core::String*>(3, "hello", 3, "hello");
+    self::A<core::int*, core::String*>* a3 = new self::F::named<core::int*, core::String*>(3, "hello");
+    self::A<core::int*, core::String*>* a4 = new self::F::named<core::int*, core::String*>(3, "hello", invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:129:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+        /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\",
+                                               ^" in "hello" as{TypeError} core::int*, invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:130:48: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
+        /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 3);
+                                               ^" in 3 as{TypeError} core::String*);
+    self::A<core::int*, core::String*>* a5 = new self::F::named<core::int*, core::String*>(3, "hello", invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_instance_creations_infer_downwards.dart:134:48: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+        /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\");
+                                               ^" in "hello" as{TypeError} core::int*);
+  }
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart.weak.modular.expect
new file mode 100644
index 0000000..871e6e1
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart.weak.modular.expect
@@ -0,0 +1,136 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:11:89: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//       /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE,error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ 42
+//                                                                                         ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:19:50: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"
+//                                                  ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:22:50: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello",
+//                                                  ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:33:61: Error: The list literal type 'List<num>' isn't of expected type 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Change the type of the list literal or the context in which it is used.
+//     List<int> l0 = /*error:INVALID_CAST_LITERAL_LIST*/ <num>[];
+//                                                             ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:34:61: Error: The list literal type 'List<num>' isn't of expected type 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Change the type of the list literal or the context in which it is used.
+//     List<int> l1 = /*error:INVALID_CAST_LITERAL_LIST*/ <num>[3];
+//                                                             ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:36:50: Error: A value of type 'String' can't be assigned to a variable of type 'num'.
+//       /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"
+//                                                  ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:35:61: Error: The list literal type 'List<num>' isn't of expected type 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Change the type of the list literal or the context in which it is used.
+//     List<int> l2 = /*error:INVALID_CAST_LITERAL_LIST*/ <num>[
+//                                                             ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:39:50: Error: A value of type 'String' can't be assigned to a variable of type 'num'.
+//       /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello",
+//                                                  ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:38:61: Error: The list literal type 'List<num>' isn't of expected type 'List<int>'.
+//  - 'List' is from 'dart:core'.
+// Change the type of the list literal or the context in which it is used.
+//     List<int> l3 = /*error:INVALID_CAST_LITERAL_LIST*/ <num>[
+//                                                             ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:47:50: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"
+//                                                  ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:50:50: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello",
+//                                                  ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:58:89: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE,error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello"
+//                                                                                         ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:61:89: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE,error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ "hello",
+//                                                                                         ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method foo([core::List<core::String*>* list1 = #C1, core::List<core::String*>* list2 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:11:89: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+      /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE,error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ 42
+                                                                                        ^"]) → void {}
+static method main() → void {
+  {
+    core::List<core::int*>* l0 = <core::int*>[];
+    core::List<core::int*>* l1 = <core::int*>[3];
+    core::List<core::int*>* l2 = <core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:19:50: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"
+                                                 ^" in "hello" as{TypeError} core::int*];
+    core::List<core::int*>* l3 = <core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:22:50: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\",
+                                                 ^" in "hello" as{TypeError} core::int*, 3];
+  }
+  {
+    core::List<dynamic>* l0 = <dynamic>[];
+    core::List<dynamic>* l1 = <dynamic>[3];
+    core::List<dynamic>* l2 = <dynamic>["hello"];
+    core::List<dynamic>* l3 = <dynamic>["hello", 3];
+  }
+  {
+    core::List<core::int*>* l0 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:33:61: Error: The list literal type 'List<num>' isn't of expected type 'List<int>'.
+ - 'List' is from 'dart:core'.
+Change the type of the list literal or the context in which it is used.
+    List<int> l0 = /*error:INVALID_CAST_LITERAL_LIST*/ <num>[];
+                                                            ^" in <core::num*>[];
+    core::List<core::int*>* l1 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:34:61: Error: The list literal type 'List<num>' isn't of expected type 'List<int>'.
+ - 'List' is from 'dart:core'.
+Change the type of the list literal or the context in which it is used.
+    List<int> l1 = /*error:INVALID_CAST_LITERAL_LIST*/ <num>[3];
+                                                            ^" in <core::num*>[3];
+    core::List<core::int*>* l2 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:35:61: Error: The list literal type 'List<num>' isn't of expected type 'List<int>'.
+ - 'List' is from 'dart:core'.
+Change the type of the list literal or the context in which it is used.
+    List<int> l2 = /*error:INVALID_CAST_LITERAL_LIST*/ <num>[
+                                                            ^" in <core::num*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:36:50: Error: A value of type 'String' can't be assigned to a variable of type 'num'.
+      /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"
+                                                 ^" in "hello" as{TypeError} core::num*];
+    core::List<core::int*>* l3 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:38:61: Error: The list literal type 'List<num>' isn't of expected type 'List<int>'.
+ - 'List' is from 'dart:core'.
+Change the type of the list literal or the context in which it is used.
+    List<int> l3 = /*error:INVALID_CAST_LITERAL_LIST*/ <num>[
+                                                            ^" in <core::num*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:39:50: Error: A value of type 'String' can't be assigned to a variable of type 'num'.
+      /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\",
+                                                 ^" in "hello" as{TypeError} core::num*, 3];
+  }
+  {
+    core::Iterable<core::int*>* i0 = <core::int*>[];
+    core::Iterable<core::int*>* i1 = <core::int*>[3];
+    core::Iterable<core::int*>* i2 = <core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:47:50: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"
+                                                 ^" in "hello" as{TypeError} core::int*];
+    core::Iterable<core::int*>* i3 = <core::int*>[invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:50:50: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\",
+                                                 ^" in "hello" as{TypeError} core::int*, 3];
+  }
+  {
+    const core::List<core::int*>* c2 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:58:89: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE,error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\"
+                                                                                        ^";
+    const core::List<core::int*>* c3 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_downwards.dart:61:89: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE,error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ \"hello\",
+                                                                                        ^";
+  }
+}
+
+constants  {
+  #C1 = <core::String*>[]
+}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_if_value_types_match_context.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_if_value_types_match_context.dart.weak.modular.expect
new file mode 100644
index 0000000..c0dae24
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_on_list_literals_infer_if_value_types_match_context.dart.weak.modular.expect
@@ -0,0 +1,91 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef Asserter<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+typedef AsserterBuilder<contravariant S extends core::Object* = dynamic, contravariant T extends core::Object* = dynamic> = (S*) →* (T*) →* void;
+class DartType extends core::Object {
+  synthetic constructor •() → self::DartType*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object {
+  static field (core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void assertBOf = null;
+  field (core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void assertAOf = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  static get assertCOf() → (core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void
+    return null;
+  abstract get assertDOf() → (core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void;
+  method method((core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void assertEOf) → dynamic {
+    let final core::List<(self::DartType*) →* void>* #t1 = <(self::DartType*) →* void>[self::_isInt, self::_isString] in this.{self::C::assertAOf}{(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void}(#t1){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+    self::C::assertBOf(<(self::DartType*) →* void>[self::_isInt, self::_isString]){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+    self::C::assertCOf(<(self::DartType*) →* void>[self::_isInt, self::_isString]){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+    let final core::List<(self::DartType*) →* void>* #t2 = <(self::DartType*) →* void>[self::_isInt, self::_isString] in this.{self::C::assertDOf}{(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void}(#t2){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+    assertEOf(<(self::DartType*) →* void>[self::_isInt, self::_isString]){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class G<T extends core::Object* = dynamic> extends core::Object {
+  field (core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void assertAOf = null;
+  synthetic constructor •() → self::G<self::G::T*>*
+    : super core::Object::•()
+    ;
+  abstract get assertDOf() → (core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void;
+  method method((core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void assertEOf) → dynamic {
+    let final core::List<(self::DartType*) →* void>* #t3 = <(self::DartType*) →* void>[self::_isInt, self::_isString] in this.{self::G::assertAOf}{(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void}(#t3){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+    let final core::List<(self::DartType*) →* void>* #t4 = <(self::DartType*) →* void>[self::_isInt, self::_isString] in this.{self::G::assertAOf}{(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void}(#t4){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+    let final core::List<(self::DartType*) →* void>* #t5 = <(self::DartType*) →* void>[self::_isInt, self::_isString] in this.{self::G::assertDOf}{(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void}(#t5){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+    assertEOf(<(self::DartType*) →* void>[self::_isInt, self::_isString]){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field (self::DartType*) →* void _isInt;
+static field (self::DartType*) →* void _isString;
+static field (core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void assertBOf;
+static get assertCOf() → (core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void
+  return null;
+static method test() → dynamic {
+  (core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void assertAOf;
+  assertAOf(<(self::DartType*) →* void>[self::_isInt, self::_isString]){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+  self::assertBOf(<(self::DartType*) →* void>[self::_isInt, self::_isString]){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+  self::assertCOf(<(self::DartType*) →* void>[self::_isInt, self::_isString]){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+  self::C::assertBOf(<(self::DartType*) →* void>[self::_isInt, self::_isString]){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+  self::C::assertCOf(<(self::DartType*) →* void>[self::_isInt, self::_isString]){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+  self::C* c;
+  let final self::C* #t6 = c in let final core::List<(self::DartType*) →* void>* #t7 = <(self::DartType*) →* void>[self::_isInt, self::_isString] in #t6.{self::C::assertAOf}{(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void}(#t7){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+  let final self::C* #t8 = c in let final core::List<(self::DartType*) →* void>* #t9 = <(self::DartType*) →* void>[self::_isInt, self::_isString] in #t8.{self::C::assertDOf}{(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void}(#t9){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+  self::G<core::int*>* g;
+  let final self::G<core::int*>* #t10 = g in let final core::List<(self::DartType*) →* void>* #t11 = <(self::DartType*) →* void>[self::_isInt, self::_isString] in #t10.{self::G::assertAOf}{(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void}(#t11){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+  let final self::G<core::int*>* #t12 = g in let final core::List<(self::DartType*) →* void>* #t13 = <(self::DartType*) →* void>[self::_isInt, self::_isString] in #t12.{self::G::assertDOf}{(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void}(#t13){(core::List<(self::DartType*) →* void>*) →* (self::DartType*) →* void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart.weak.modular.expect
new file mode 100644
index 0000000..ab58333
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart.weak.modular.expect
@@ -0,0 +1,161 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:12:79: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*error:MAP_KEY_TYPE_NOT_ASSIGNABLE,error:MAP_KEY_TYPE_NOT_ASSIGNABLE*/ "hello":
+//                                                                               ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:20:45: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*error:MAP_KEY_TYPE_NOT_ASSIGNABLE*/ "hello": "hello"
+//                                             ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:23:50: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//       3: /*error:MAP_VALUE_TYPE_NOT_ASSIGNABLE*/ 3
+//                                                  ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:27:45: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*error:MAP_KEY_TYPE_NOT_ASSIGNABLE*/ "hello":
+//                                             ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:28:51: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//           /*error:MAP_VALUE_TYPE_NOT_ASSIGNABLE*/ 3
+//                                                   ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:48:50: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//       3: /*error:MAP_VALUE_TYPE_NOT_ASSIGNABLE*/ 3
+//                                                  ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:52:56: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//       "hello": /*error:MAP_VALUE_TYPE_NOT_ASSIGNABLE*/ 3
+//                                                        ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:59:45: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*error:MAP_KEY_TYPE_NOT_ASSIGNABLE*/ "hello": "hello"
+//                                             ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:64:45: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*error:MAP_KEY_TYPE_NOT_ASSIGNABLE*/ "hello": 3
+//                                             ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:68:76: Error: The map literal type 'Map<num, dynamic>' isn't of expected type 'Map<int, String>'.
+//  - 'Map' is from 'dart:core'.
+// Change the type of the map literal or the context in which it is used.
+//     Map<int, String> l0 = /*error:INVALID_CAST_LITERAL_MAP*/ <num, dynamic>{};
+//                                                                            ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:69:76: Error: The map literal type 'Map<num, dynamic>' isn't of expected type 'Map<int, String>'.
+//  - 'Map' is from 'dart:core'.
+// Change the type of the map literal or the context in which it is used.
+//     Map<int, String> l1 = /*error:INVALID_CAST_LITERAL_MAP*/ <num, dynamic>{
+//                                                                            ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:72:76: Error: The map literal type 'Map<num, dynamic>' isn't of expected type 'Map<int, String>'.
+//  - 'Map' is from 'dart:core'.
+// Change the type of the map literal or the context in which it is used.
+//     Map<int, String> l3 = /*error:INVALID_CAST_LITERAL_MAP*/ <num, dynamic>{
+//                                                                            ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:80:79: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*error:MAP_KEY_TYPE_NOT_ASSIGNABLE,error:MAP_KEY_TYPE_NOT_ASSIGNABLE*/ "hello":
+//                                                                               ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:84:86: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//       3: /*error:MAP_VALUE_TYPE_NOT_ASSIGNABLE,error:MAP_VALUE_TYPE_NOT_ASSIGNABLE*/ 3
+//                                                                                      ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:88:79: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*error:MAP_KEY_TYPE_NOT_ASSIGNABLE,error:MAP_KEY_TYPE_NOT_ASSIGNABLE*/ "hello":
+//                                                                               ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:89:87: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//           /*error:MAP_VALUE_TYPE_NOT_ASSIGNABLE,error:MAP_VALUE_TYPE_NOT_ASSIGNABLE*/ 3
+//                                                                                       ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method foo([core::Map<core::int*, core::String*>* m1 = #C3, core::Map<core::int*, core::String*>* m2 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:12:79: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*error:MAP_KEY_TYPE_NOT_ASSIGNABLE,error:MAP_KEY_TYPE_NOT_ASSIGNABLE*/ \"hello\":
+                                                                              ^"]) → void {}
+static method test() → void {
+  {
+    core::Map<core::int*, core::String*>* l0 = <core::int*, core::String*>{};
+    core::Map<core::int*, core::String*>* l1 = <core::int*, core::String*>{3: "hello"};
+    core::Map<core::int*, core::String*>* l2 = <core::int*, core::String*>{invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:20:45: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*error:MAP_KEY_TYPE_NOT_ASSIGNABLE*/ \"hello\": \"hello\"
+                                            ^" in "hello" as{TypeError} core::int*: "hello"};
+    core::Map<core::int*, core::String*>* l3 = <core::int*, core::String*>{3: invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:23:50: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+      3: /*error:MAP_VALUE_TYPE_NOT_ASSIGNABLE*/ 3
+                                                 ^" in 3 as{TypeError} core::String*};
+    core::Map<core::int*, core::String*>* l4 = <core::int*, core::String*>{3: "hello", invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:27:45: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*error:MAP_KEY_TYPE_NOT_ASSIGNABLE*/ \"hello\":
+                                            ^" in "hello" as{TypeError} core::int*: invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:28:51: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+          /*error:MAP_VALUE_TYPE_NOT_ASSIGNABLE*/ 3
+                                                  ^" in 3 as{TypeError} core::String*};
+  }
+  {
+    core::Map<dynamic, dynamic>* l0 = <dynamic, dynamic>{};
+    core::Map<dynamic, dynamic>* l1 = <dynamic, dynamic>{3: "hello"};
+    core::Map<dynamic, dynamic>* l2 = <dynamic, dynamic>{"hello": "hello"};
+    core::Map<dynamic, dynamic>* l3 = <dynamic, dynamic>{3: 3};
+    core::Map<dynamic, dynamic>* l4 = <dynamic, dynamic>{3: "hello", "hello": 3};
+  }
+  {
+    core::Map<dynamic, core::String*>* l0 = <dynamic, core::String*>{};
+    core::Map<dynamic, core::String*>* l1 = <dynamic, core::String*>{3: "hello"};
+    core::Map<dynamic, core::String*>* l2 = <dynamic, core::String*>{"hello": "hello"};
+    core::Map<dynamic, core::String*>* l3 = <dynamic, core::String*>{3: invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:48:50: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+      3: /*error:MAP_VALUE_TYPE_NOT_ASSIGNABLE*/ 3
+                                                 ^" in 3 as{TypeError} core::String*};
+    core::Map<dynamic, core::String*>* l4 = <dynamic, core::String*>{3: "hello", "hello": invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:52:56: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+      \"hello\": /*error:MAP_VALUE_TYPE_NOT_ASSIGNABLE*/ 3
+                                                       ^" in 3 as{TypeError} core::String*};
+  }
+  {
+    core::Map<core::int*, dynamic>* l0 = <core::int*, dynamic>{};
+    core::Map<core::int*, dynamic>* l1 = <core::int*, dynamic>{3: "hello"};
+    core::Map<core::int*, dynamic>* l2 = <core::int*, dynamic>{invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:59:45: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*error:MAP_KEY_TYPE_NOT_ASSIGNABLE*/ \"hello\": \"hello\"
+                                            ^" in "hello" as{TypeError} core::int*: "hello"};
+    core::Map<core::int*, dynamic>* l3 = <core::int*, dynamic>{3: 3};
+    core::Map<core::int*, dynamic>* l4 = <core::int*, dynamic>{3: "hello", invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:64:45: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*error:MAP_KEY_TYPE_NOT_ASSIGNABLE*/ \"hello\": 3
+                                            ^" in "hello" as{TypeError} core::int*: 3};
+  }
+  {
+    core::Map<core::int*, core::String*>* l0 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:68:76: Error: The map literal type 'Map<num, dynamic>' isn't of expected type 'Map<int, String>'.
+ - 'Map' is from 'dart:core'.
+Change the type of the map literal or the context in which it is used.
+    Map<int, String> l0 = /*error:INVALID_CAST_LITERAL_MAP*/ <num, dynamic>{};
+                                                                           ^" in <core::num*, dynamic>{};
+    core::Map<core::int*, core::String*>* l1 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:69:76: Error: The map literal type 'Map<num, dynamic>' isn't of expected type 'Map<int, String>'.
+ - 'Map' is from 'dart:core'.
+Change the type of the map literal or the context in which it is used.
+    Map<int, String> l1 = /*error:INVALID_CAST_LITERAL_MAP*/ <num, dynamic>{
+                                                                           ^" in <core::num*, dynamic>{3: "hello"};
+    core::Map<core::int*, core::String*>* l3 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:72:76: Error: The map literal type 'Map<num, dynamic>' isn't of expected type 'Map<int, String>'.
+ - 'Map' is from 'dart:core'.
+Change the type of the map literal or the context in which it is used.
+    Map<int, String> l3 = /*error:INVALID_CAST_LITERAL_MAP*/ <num, dynamic>{
+                                                                           ^" in <core::num*, dynamic>{3: 3};
+  }
+  {
+    const core::Map<core::int*, core::String*>* l2 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:80:79: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*error:MAP_KEY_TYPE_NOT_ASSIGNABLE,error:MAP_KEY_TYPE_NOT_ASSIGNABLE*/ \"hello\":
+                                                                              ^";
+    const core::Map<core::int*, core::String*>* l3 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:84:86: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+      3: /*error:MAP_VALUE_TYPE_NOT_ASSIGNABLE,error:MAP_VALUE_TYPE_NOT_ASSIGNABLE*/ 3
+                                                                                     ^";
+    const core::Map<core::int*, core::String*>* l4 = invalid-expression "pkg/front_end/testcases/inference/downwards_inference_on_map_literals.dart:88:79: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*error:MAP_KEY_TYPE_NOT_ASSIGNABLE,error:MAP_KEY_TYPE_NOT_ASSIGNABLE*/ \"hello\":
+                                                                              ^";
+  }
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 1
+  #C2 = "hello"
+  #C3 = <core::int*, core::String*>{#C1:#C2)
+}
diff --git a/pkg/front_end/testcases/inference/downwards_inference_yield_yield_star.dart.weak.modular.expect b/pkg/front_end/testcases/inference/downwards_inference_yield_yield_star.dart.weak.modular.expect
new file mode 100644
index 0000000..5951999
--- /dev/null
+++ b/pkg/front_end/testcases/inference/downwards_inference_yield_yield_star.dart.weak.modular.expect
@@ -0,0 +1,119 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/downwards_inference_yield_yield_star.dart:16:69: Error: A value of type 'MyStream<dynamic>' can't be assigned to a variable of type 'List<int>'.
+//  - 'MyStream' is from 'pkg/front_end/testcases/inference/downwards_inference_yield_yield_star.dart'.
+//  - 'List' is from 'dart:core'.
+//   yield /*error:YIELD_OF_INVALID_TYPE*/ new /*@ typeArgs=dynamic */ MyStream();
+//                                                                     ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_yield_yield_star.dart:17:64: Error: A value of type 'List<dynamic>' can't be assigned to a variable of type 'Stream<List<int>>'.
+//  - 'List' is from 'dart:core'.
+//  - 'Stream' is from 'dart:async'.
+//   yield* /*error:YIELD_OF_INVALID_TYPE*/ /*@typeArgs=dynamic*/ [];
+//                                                                ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_yield_yield_star.dart:23:63: Error: A value of type 'List<dynamic>' can't be assigned to a variable of type 'Map<int, int>'.
+//  - 'List' is from 'dart:core'.
+//  - 'Map' is from 'dart:core'.
+//   yield /*error:YIELD_OF_INVALID_TYPE*/ /*@typeArgs=dynamic*/ [];
+//                                                               ^
+//
+// pkg/front_end/testcases/inference/downwards_inference_yield_yield_star.dart:24:79: Error: A value of type 'Map<dynamic, dynamic>' can't be assigned to a variable of type 'Iterable<Map<int, int>>'.
+//  - 'Map' is from 'dart:core'.
+//  - 'Iterable' is from 'dart:core'.
+//   yield* /*error:YIELD_OF_INVALID_TYPE*/ new /*@ typeArgs=dynamic, dynamic */ Map();
+//                                                                               ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+abstract class MyStream<T extends core::Object* = dynamic> extends asy::Stream<self::MyStream::T*> {
+  static factory •<T extends core::Object* = dynamic>() → self::MyStream<self::MyStream::•::T*>*
+    return null;
+  abstract member-signature get isBroadcast() → core::bool*; -> asy::Stream::isBroadcast
+  abstract member-signature method asBroadcastStream({(asy::StreamSubscription<self::MyStream::T*>*) →* void onListen = #C1, (asy::StreamSubscription<self::MyStream::T*>*) →* void onCancel = #C1}) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::asBroadcastStream
+  abstract member-signature method where((self::MyStream::T*) →* core::bool* test) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::where
+  abstract member-signature method map<S extends core::Object* = dynamic>((self::MyStream::T*) →* self::MyStream::map::S* convert) → asy::Stream<self::MyStream::map::S*>*; -> asy::Stream::map
+  abstract member-signature method asyncMap<E extends core::Object* = dynamic>((self::MyStream::T*) →* FutureOr<self::MyStream::asyncMap::E*>* convert) → asy::Stream<self::MyStream::asyncMap::E*>*; -> asy::Stream::asyncMap
+  abstract member-signature method asyncExpand<E extends core::Object* = dynamic>((self::MyStream::T*) →* asy::Stream<self::MyStream::asyncExpand::E*>* convert) → asy::Stream<self::MyStream::asyncExpand::E*>*; -> asy::Stream::asyncExpand
+  abstract member-signature method handleError(core::Function* onError, {(dynamic) →* core::bool* test = #C1}) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::handleError
+  abstract member-signature method expand<S extends core::Object* = dynamic>((self::MyStream::T*) →* core::Iterable<self::MyStream::expand::S*>* convert) → asy::Stream<self::MyStream::expand::S*>*; -> asy::Stream::expand
+  abstract member-signature method pipe(covariant-by-class asy::StreamConsumer<self::MyStream::T*>* streamConsumer) → asy::Future<dynamic>*; -> asy::Stream::pipe
+  abstract member-signature method transform<S extends core::Object* = dynamic>(covariant-by-class asy::StreamTransformer<self::MyStream::T*, self::MyStream::transform::S*>* streamTransformer) → asy::Stream<self::MyStream::transform::S*>*; -> asy::Stream::transform
+  abstract member-signature method reduce(covariant-by-class (self::MyStream::T*, self::MyStream::T*) →* self::MyStream::T* combine) → asy::Future<self::MyStream::T*>*; -> asy::Stream::reduce
+  abstract member-signature method fold<S extends core::Object* = dynamic>(self::MyStream::fold::S* initialValue, (self::MyStream::fold::S*, self::MyStream::T*) →* self::MyStream::fold::S* combine) → asy::Future<self::MyStream::fold::S*>*; -> asy::Stream::fold
+  abstract member-signature method join([core::String* separator = #C2]) → asy::Future<core::String*>*; -> asy::Stream::join
+  abstract member-signature method contains(core::Object* needle) → asy::Future<core::bool*>*; -> asy::Stream::contains
+  abstract member-signature method forEach((self::MyStream::T*) →* void action) → asy::Future<dynamic>*; -> asy::Stream::forEach
+  abstract member-signature method every((self::MyStream::T*) →* core::bool* test) → asy::Future<core::bool*>*; -> asy::Stream::every
+  abstract member-signature method any((self::MyStream::T*) →* core::bool* test) → asy::Future<core::bool*>*; -> asy::Stream::any
+  abstract member-signature get length() → asy::Future<core::int*>*; -> asy::Stream::length
+  abstract member-signature get isEmpty() → asy::Future<core::bool*>*; -> asy::Stream::isEmpty
+  abstract member-signature method cast<R extends core::Object* = dynamic>() → asy::Stream<self::MyStream::cast::R*>*; -> asy::Stream::cast
+  abstract member-signature method toList() → asy::Future<core::List<self::MyStream::T*>*>*; -> asy::Stream::toList
+  abstract member-signature method toSet() → asy::Future<core::Set<self::MyStream::T*>*>*; -> asy::Stream::toSet
+  abstract member-signature method drain<E extends core::Object* = dynamic>([self::MyStream::drain::E* futureValue = #C1]) → asy::Future<self::MyStream::drain::E*>*; -> asy::Stream::drain
+  abstract member-signature method take(core::int* count) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::take
+  abstract member-signature method takeWhile((self::MyStream::T*) →* core::bool* test) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::takeWhile
+  abstract member-signature method skip(core::int* count) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::skip
+  abstract member-signature method skipWhile((self::MyStream::T*) →* core::bool* test) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::skipWhile
+  abstract member-signature method distinct([(self::MyStream::T*, self::MyStream::T*) →* core::bool* equals = #C1]) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::distinct
+  abstract member-signature get first() → asy::Future<self::MyStream::T*>*; -> asy::Stream::first
+  abstract member-signature get last() → asy::Future<self::MyStream::T*>*; -> asy::Stream::last
+  abstract member-signature get single() → asy::Future<self::MyStream::T*>*; -> asy::Stream::single
+  abstract member-signature method firstWhere((self::MyStream::T*) →* core::bool* test, {covariant-by-class () →* self::MyStream::T* orElse = #C1}) → asy::Future<self::MyStream::T*>*; -> asy::Stream::firstWhere
+  abstract member-signature method lastWhere((self::MyStream::T*) →* core::bool* test, {covariant-by-class () →* self::MyStream::T* orElse = #C1}) → asy::Future<self::MyStream::T*>*; -> asy::Stream::lastWhere
+  abstract member-signature method singleWhere((self::MyStream::T*) →* core::bool* test, {covariant-by-class () →* self::MyStream::T* orElse = #C1}) → asy::Future<self::MyStream::T*>*; -> asy::Stream::singleWhere
+  abstract member-signature method elementAt(core::int* index) → asy::Future<self::MyStream::T*>*; -> asy::Stream::elementAt
+  abstract member-signature method timeout(core::Duration* timeLimit, {(asy::EventSink<self::MyStream::T*>*) →* void onTimeout = #C1}) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::timeout
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature method listen((self::MyStream::T*) →* void onData, {core::Function* onError = #C1, () →* void onDone = #C1, core::bool* cancelOnError = #C1}) → asy::StreamSubscription<self::MyStream::T*>*; -> asy::Stream::listen
+}
+static method foo() → asy::Stream<core::List<core::int*>*>* async* {
+  yield<core::int*>[];
+  yield invalid-expression "pkg/front_end/testcases/inference/downwards_inference_yield_yield_star.dart:16:69: Error: A value of type 'MyStream<dynamic>' can't be assigned to a variable of type 'List<int>'.
+ - 'MyStream' is from 'pkg/front_end/testcases/inference/downwards_inference_yield_yield_star.dart'.
+ - 'List' is from 'dart:core'.
+  yield /*error:YIELD_OF_INVALID_TYPE*/ new /*@ typeArgs=dynamic */ MyStream();
+                                                                    ^" in self::MyStream::•<dynamic>() as{TypeError} core::List<core::int*>*;
+  yield* invalid-expression "pkg/front_end/testcases/inference/downwards_inference_yield_yield_star.dart:17:64: Error: A value of type 'List<dynamic>' can't be assigned to a variable of type 'Stream<List<int>>'.
+ - 'List' is from 'dart:core'.
+ - 'Stream' is from 'dart:async'.
+  yield* /*error:YIELD_OF_INVALID_TYPE*/ /*@typeArgs=dynamic*/ [];
+                                                               ^" in <dynamic>[] as{TypeError} asy::Stream<core::List<core::int*>*>*;
+  yield* self::MyStream::•<core::List<core::int*>*>();
+}
+static method bar() → core::Iterable<core::Map<core::int*, core::int*>*>* sync* {
+  yield core::Map::•<core::int*, core::int*>();
+  yield invalid-expression "pkg/front_end/testcases/inference/downwards_inference_yield_yield_star.dart:23:63: Error: A value of type 'List<dynamic>' can't be assigned to a variable of type 'Map<int, int>'.
+ - 'List' is from 'dart:core'.
+ - 'Map' is from 'dart:core'.
+  yield /*error:YIELD_OF_INVALID_TYPE*/ /*@typeArgs=dynamic*/ [];
+                                                              ^" in <dynamic>[] as{TypeError} core::Map<core::int*, core::int*>*;
+  yield* invalid-expression "pkg/front_end/testcases/inference/downwards_inference_yield_yield_star.dart:24:79: Error: A value of type 'Map<dynamic, dynamic>' can't be assigned to a variable of type 'Iterable<Map<int, int>>'.
+ - 'Map' is from 'dart:core'.
+ - 'Iterable' is from 'dart:core'.
+  yield* /*error:YIELD_OF_INVALID_TYPE*/ new /*@ typeArgs=dynamic, dynamic */ Map();
+                                                                              ^" in core::Map::•<dynamic, dynamic>() as{TypeError} core::Iterable<core::Map<core::int*, core::int*>*>*;
+  yield*<core::Map<core::int*, core::int*>*>[];
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = ""
+}
diff --git a/pkg/front_end/testcases/inference/dynamic_methods.dart.weak.modular.expect b/pkg/front_end/testcases/inference/dynamic_methods.dart.weak.modular.expect
new file mode 100644
index 0000000..3cc9299
--- /dev/null
+++ b/pkg/front_end/testcases/inference/dynamic_methods.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/dynamic_methods.dart:16:46: Error: 'hashCode' isn't a function or method and can't be invoked.
+//       d. /*@target=Object.hashCode*/ hashCode();
+//                                              ^^^^...
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  method foo(core::int* x) → core::int*
+    return x;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  dynamic d = new self::Foo::•();
+  core::int* get_hashCode = d.{core::Object::hashCode}{core::int*};
+  dynamic call_hashCode = invalid-expression "pkg/front_end/testcases/inference/dynamic_methods.dart:16:46: Error: 'hashCode' isn't a function or method and can't be invoked.
+      d. /*@target=Object.hashCode*/ hashCode();
+                                             ^^^^..." in d.{core::Object::hashCode}{core::int*}{<unresolved>}.call();
+  core::String* call_toString = d.{core::Object::toString}(){() →* core::String*};
+  dynamic call_toStringArg = d{dynamic}.toString(color: "pink");
+  dynamic call_foo0 = d{dynamic}.foo();
+  dynamic call_foo1 = d{dynamic}.foo(1);
+  dynamic call_foo2 = d{dynamic}.foo(1, 2);
+  dynamic call_nsm0 = d{dynamic}.noSuchMethod();
+  dynamic call_nsm1 = d.{core::Object::noSuchMethod}(null){(core::Invocation*) →* dynamic};
+  dynamic call_nsm2 = d{dynamic}.noSuchMethod(null, null);
+  core::bool* equals_self = d =={core::Object::==}{(core::Object*) →* core::bool*} d;
+  core::bool* equals_null = d == null;
+  core::bool* null_equals = d == null;
+  core::bool* not_equals_self = !(d =={core::Object::==}{(core::Object*) →* core::bool*} d);
+  core::bool* not_equals_null = !(d == null);
+  core::bool* null_not_equals = !(d == null);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/field_initializer_context_explicit.dart.weak.modular.expect b/pkg/front_end/testcases/inference/field_initializer_context_explicit.dart.weak.modular.expect
new file mode 100644
index 0000000..be4cd27
--- /dev/null
+++ b/pkg/front_end/testcases/inference/field_initializer_context_explicit.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  final field core::int* x;
+  constructor •() → self::C*
+    : self::C::x = self::f<core::int*>(), super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/field_initializer_context_implicit.dart.weak.modular.expect b/pkg/front_end/testcases/inference/field_initializer_context_implicit.dart.weak.modular.expect
new file mode 100644
index 0000000..4be2a2e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/field_initializer_context_implicit.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object implements self::B {
+  final field core::int* x;
+  constructor •() → self::C*
+    : self::C::x = self::f<core::int*>(), super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/field_initializer_context_this.dart.weak.modular.expect b/pkg/front_end/testcases/inference/field_initializer_context_this.dart.weak.modular.expect
new file mode 100644
index 0000000..be4cd27
--- /dev/null
+++ b/pkg/front_end/testcases/inference/field_initializer_context_this.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  final field core::int* x;
+  constructor •() → self::C*
+    : self::C::x = self::f<core::int*>(), super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/field_initializer_parameter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/field_initializer_parameter.dart.weak.modular.expect
new file mode 100644
index 0000000..fa1a596
--- /dev/null
+++ b/pkg/front_end/testcases/inference/field_initializer_parameter.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  final field dynamic x;
+  constructor •(core::int* p) → self::C*
+    : self::C::x = self::f<core::int*>(p), super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>(self::f::T* t) → self::f::T*
+  return t;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/field_refers_to_static_getter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/field_refers_to_static_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..0c7c096
--- /dev/null
+++ b/pkg/front_end/testcases/inference/field_refers_to_static_getter.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  final field core::int* x = self::C::_x;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  static get _x() → core::int*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/field_refers_to_top_level_getter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/field_refers_to_top_level_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..f7f1c21
--- /dev/null
+++ b/pkg/front_end/testcases/inference/field_refers_to_top_level_getter.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  final field core::int* x = self::y;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static get y() → core::int*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/for_each_downcast_iterable.dart.weak.modular.expect b/pkg/front_end/testcases/inference/for_each_downcast_iterable.dart.weak.modular.expect
new file mode 100644
index 0000000..93ecd39
--- /dev/null
+++ b/pkg/front_end/testcases/inference/for_each_downcast_iterable.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+static method test() → dynamic async {
+  core::Object* o;
+  for (dynamic x in o as{TypeError} core::Iterable<dynamic>*) {
+  }
+  await for (dynamic x in o as{TypeError} asy::Stream<dynamic>*) {
+  }
+  core::int* y;
+  for (final dynamic #t1 in o as{TypeError} core::Iterable<dynamic>*) {
+    y = #t1 as{TypeError,ForDynamic} core::int*;
+  }
+  await for (final dynamic #t2 in o as{TypeError} asy::Stream<dynamic>*) {
+    y = #t2 as{TypeError,ForDynamic} core::int*;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/for_in_loop_promotion.dart.weak.modular.expect b/pkg/front_end/testcases/inference/for_in_loop_promotion.dart.weak.modular.expect
new file mode 100644
index 0000000..f98e42e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/for_in_loop_promotion.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test(core::List<core::num*>* nums) → void {
+  for (core::num* x in nums) {
+    if(x is core::int*) {
+      core::int* y = x{core::int*};
+    }
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/for_loop_empty_condition.dart.weak.modular.expect b/pkg/front_end/testcases/inference/for_loop_empty_condition.dart.weak.modular.expect
new file mode 100644
index 0000000..f17816f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/for_loop_empty_condition.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  #L1:
+  for (core::num* x = 0; ; x = x.{core::num::+}(1){(core::num*) →* core::num*}) {
+    if(x.{core::num::>=}(10){(core::num*) →* core::bool*})
+      break #L1;
+    if(x is core::int*) {
+      core::int* y = x{core::int*};
+    }
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/for_loop_initializer_expression.dart.weak.modular.expect b/pkg/front_end/testcases/inference/for_loop_initializer_expression.dart.weak.modular.expect
new file mode 100644
index 0000000..8f36a9c
--- /dev/null
+++ b/pkg/front_end/testcases/inference/for_loop_initializer_expression.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  core::num* x;
+  for (final core::int* #t1 = x = 0; x.{core::num::<}(10){(core::num*) →* core::bool*}; x = x.{core::num::+}(1){(core::num*) →* core::num*}) {
+    if(x is core::int*) {
+      core::int* y = x{core::int*};
+    }
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/for_loop_promotion.dart.weak.modular.expect b/pkg/front_end/testcases/inference/for_loop_promotion.dart.weak.modular.expect
new file mode 100644
index 0000000..6cecf17
--- /dev/null
+++ b/pkg/front_end/testcases/inference/for_loop_promotion.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  for (core::num* x = 0; x.{core::num::<}(10){(core::num*) →* core::bool*}; x = x.{core::num::+}(1){(core::num*) →* core::num*}) {
+    if(x is core::int*) {
+      core::int* y = x{core::int*};
+    }
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/future_or_subtyping.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_or_subtyping.dart.weak.modular.expect
new file mode 100644
index 0000000..36d60ee
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_or_subtyping.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+static method add(core::int* x) → void {}
+static method add2(core::int* y) → dynamic {}
+static method test() → dynamic {
+  asy::Future<core::int*>* f;
+  asy::Future<void>* a = f.{asy::Future::then}<void>(#C1){((core::int*) →* FutureOr<void>*, {onError: core::Function*}) →* asy::Future<void>*};
+  asy::Future<dynamic>* b = f.{asy::Future::then}<dynamic>(#C2){((core::int*) →* FutureOr<dynamic>*, {onError: core::Function*}) →* asy::Future<dynamic>*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::add
+  #C2 = static-tearoff self::add2
+}
diff --git a/pkg/front_end/testcases/inference/future_then.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then.dart.weak.modular.expect
new file mode 100644
index 0000000..3472083
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then.dart.weak.modular.expect
@@ -0,0 +1,67 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method test() → void {
+  self::MyFuture<dynamic>* f;
+  asy::Future<core::int*>* t1 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => await asy::Future::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t2 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return await asy::Future::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t3 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => 3){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t4 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return 3;
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t5 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* => asy::Future::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t6 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* {
+    return asy::Future::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t7 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => asy::Future::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t8 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return asy::Future::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_2.dart.weak.modular.expect
new file mode 100644
index 0000000..caba7e5
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_2.dart.weak.modular.expect
@@ -0,0 +1,67 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method test() → void {
+  self::MyFuture<dynamic>* f;
+  asy::Future<core::int*>* t1 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => await new self::MyFuture::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t2 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return await new self::MyFuture::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t3 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => 3){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t4 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return 3;
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t5 = f.{self::MyFuture::then}<core::int*>((dynamic _) → self::MyFuture<core::int*>* => new self::MyFuture::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t6 = f.{self::MyFuture::then}<core::int*>((dynamic _) → self::MyFuture<core::int*>* {
+    return new self::MyFuture::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t7 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => new self::MyFuture::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t8 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return new self::MyFuture::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_3.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_3.dart.weak.modular.expect
new file mode 100644
index 0000000..1efc406
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_3.dart.weak.modular.expect
@@ -0,0 +1,67 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method test() → void {
+  self::MyFuture<dynamic>* f;
+  self::MyFuture<core::int*>* t1 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => await asy::Future::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t2 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return await asy::Future::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t3 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => 3){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t4 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return 3;
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t5 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* => asy::Future::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t6 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* {
+    return asy::Future::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t7 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => asy::Future::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t8 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return asy::Future::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_4.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_4.dart.weak.modular.expect
new file mode 100644
index 0000000..eaff2a5
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_4.dart.weak.modular.expect
@@ -0,0 +1,67 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method test() → void {
+  self::MyFuture<dynamic>* f;
+  self::MyFuture<core::int*>* t1 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => await new self::MyFuture::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t2 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return await new self::MyFuture::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t3 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => 3){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t4 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return 3;
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t5 = f.{self::MyFuture::then}<core::int*>((dynamic _) → self::MyFuture<core::int*>* => new self::MyFuture::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t6 = f.{self::MyFuture::then}<core::int*>((dynamic _) → self::MyFuture<core::int*>* {
+    return new self::MyFuture::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t7 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => new self::MyFuture::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t8 = f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return new self::MyFuture::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_5.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_5.dart.weak.modular.expect
new file mode 100644
index 0000000..955cbb3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_5.dart.weak.modular.expect
@@ -0,0 +1,67 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method test() → void {
+  asy::Future<dynamic>* f;
+  asy::Future<core::int*>* t1 = f.{asy::Future::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => await new self::MyFuture::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t2 = f.{asy::Future::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return await new self::MyFuture::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t3 = f.{asy::Future::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => 3){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t4 = f.{asy::Future::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return 3;
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t5 = f.{asy::Future::then}<core::int*>((dynamic _) → self::MyFuture<core::int*>* => new self::MyFuture::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t6 = f.{asy::Future::then}<core::int*>((dynamic _) → self::MyFuture<core::int*>* {
+    return new self::MyFuture::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t7 = f.{asy::Future::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => new self::MyFuture::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t8 = f.{asy::Future::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return new self::MyFuture::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_6.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_6.dart.weak.modular.expect
new file mode 100644
index 0000000..438bfac
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_6.dart.weak.modular.expect
@@ -0,0 +1,67 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method test() → void {
+  asy::Future<dynamic>* f;
+  asy::Future<core::int*>* t1 = f.{asy::Future::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => await asy::Future::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t2 = f.{asy::Future::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return await asy::Future::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t3 = f.{asy::Future::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => 3){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t4 = f.{asy::Future::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return 3;
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t5 = f.{asy::Future::then}<core::int*>((dynamic _) → asy::Future<core::int*>* => asy::Future::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t6 = f.{asy::Future::then}<core::int*>((dynamic _) → asy::Future<core::int*>* {
+    return asy::Future::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t7 = f.{asy::Future::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async => asy::Future::value<core::int*>(3)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t8 = f.{asy::Future::then}<core::int*>((dynamic _) → asy::Future<core::int*>* async {
+    return asy::Future::value<core::int*>(3);
+  }){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_conditional.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_conditional.dart.weak.modular.expect
new file mode 100644
index 0000000..816b3ee
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_conditional.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method test() → void {
+  self::MyFuture<core::bool*>* f;
+  asy::Future<core::int*>* t1 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → asy::Future<core::int*>* async => x ?{core::int*} 2 : await asy::Future::value<core::int*>(3)){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t2 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* async {
+    return (await x ?{core::Object*} 2 : asy::Future::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*;
+  }){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t5 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* => (x ?{core::Object*} 2 : asy::Future::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t6 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* {
+    return (x ?{core::Object*} 2 : asy::Future::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*;
+  }){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_conditional_2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_conditional_2.dart.weak.modular.expect
new file mode 100644
index 0000000..11b74949
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_conditional_2.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method test() → void {
+  self::MyFuture<core::bool*>* f;
+  asy::Future<core::int*>* t1 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → asy::Future<core::int*>* async => x ?{core::int*} 2 : await new self::MyFuture::value<core::int*>(3)){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t2 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* async {
+    return (await x ?{core::Object*} 2 : new self::MyFuture::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*;
+  }){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t5 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* => (x ?{core::Object*} 2 : new self::MyFuture::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t6 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* {
+    return (x ?{core::Object*} 2 : new self::MyFuture::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*;
+  }){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_conditional_3.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_conditional_3.dart.weak.modular.expect
new file mode 100644
index 0000000..11b63b1
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_conditional_3.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method test() → void {
+  self::MyFuture<core::bool*>* f;
+  self::MyFuture<core::int*>* t1 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → asy::Future<core::int*>* async => x ?{core::int*} 2 : await asy::Future::value<core::int*>(3)){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t2 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* async {
+    return (await x ?{core::Object*} 2 : asy::Future::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*;
+  }){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t5 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* => (x ?{core::Object*} 2 : asy::Future::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t6 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* {
+    return (x ?{core::Object*} 2 : asy::Future::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*;
+  }){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_conditional_4.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_conditional_4.dart.weak.modular.expect
new file mode 100644
index 0000000..cc3ada3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_conditional_4.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method test() → void {
+  self::MyFuture<core::bool*>* f;
+  self::MyFuture<core::int*>* t1 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → asy::Future<core::int*>* async => x ?{core::int*} 2 : await new self::MyFuture::value<core::int*>(3)){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t2 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* async {
+    return (await x ?{core::Object*} 2 : new self::MyFuture::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*;
+  }){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t5 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* => (x ?{core::Object*} 2 : new self::MyFuture::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  self::MyFuture<core::int*>* t6 = f.{self::MyFuture::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* {
+    return (x ?{core::Object*} 2 : new self::MyFuture::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*;
+  }){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_conditional_5.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_conditional_5.dart.weak.modular.expect
new file mode 100644
index 0000000..83acf25
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_conditional_5.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method test() → void {
+  asy::Future<core::bool*>* f;
+  asy::Future<core::int*>* t1 = f.{asy::Future::then}<core::int*>((core::bool* x) → asy::Future<core::int*>* async => x ?{core::int*} 2 : await new self::MyFuture::value<core::int*>(3)){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t2 = f.{asy::Future::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* async {
+    return (await x ?{core::Object*} 2 : new self::MyFuture::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*;
+  }){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t5 = f.{asy::Future::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* => (x ?{core::Object*} 2 : new self::MyFuture::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t6 = f.{asy::Future::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* {
+    return (x ?{core::Object*} 2 : new self::MyFuture::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*;
+  }){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_conditional_6.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_conditional_6.dart.weak.modular.expect
new file mode 100644
index 0000000..0c2809d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_conditional_6.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method test() → void {
+  asy::Future<core::bool*>* f;
+  asy::Future<core::int*>* t1 = f.{asy::Future::then}<core::int*>((core::bool* x) → asy::Future<core::int*>* async => x ?{core::int*} 2 : await asy::Future::value<core::int*>(3)){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t2 = f.{asy::Future::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* async {
+    return (await x ?{core::Object*} 2 : asy::Future::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*;
+  }){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t5 = f.{asy::Future::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* => (x ?{core::Object*} 2 : asy::Future::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+  asy::Future<core::int*>* t6 = f.{asy::Future::then}<core::int*>((core::bool* x) → FutureOr<core::int*>* {
+    return (x ?{core::Object*} 2 : asy::Future::value<core::int*>(3)) as{TypeError} FutureOr<core::int*>*;
+  }){((core::bool*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_downwards_method_target.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_downwards_method_target.dart.weak.modular.expect
new file mode 100644
index 0000000..7024c62
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_downwards_method_target.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library test;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "dart:async";
+
+static method test() → dynamic {
+  asy::Future<core::int*>* f;
+  asy::Future<core::List<core::int*>*>* b = f.{asy::Future::then}<core::List<dynamic>*>((core::int* x) → core::List<dynamic>* => <dynamic>[]){((core::int*) →* FutureOr<core::List<dynamic>*>*, {onError: core::Function*}) →* asy::Future<core::List<dynamic>*>*}.{asy::Future::whenComplete}(() → Null {}){(() →* FutureOr<void>*) →* asy::Future<core::List<dynamic>*>*} as{TypeError} asy::Future<core::List<core::int*>*>*;
+  b = f.{asy::Future::then}<core::List<core::int*>*>((core::int* x) → core::List<core::int*>* => <core::int*>[]){((core::int*) →* FutureOr<core::List<core::int*>*>*, {onError: core::Function*}) →* asy::Future<core::List<core::int*>*>*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/future_then_explicit_future.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_explicit_future.dart.weak.modular.expect
new file mode 100644
index 0000000..668e6c8
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_explicit_future.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/future_then_explicit_future.dart:15:99: Error: A value of type 'List<dynamic>' can't be assigned to a variable of type 'FutureOr<Future<List<int>>>'.
+//  - 'List' is from 'dart:core'.
+//  - 'Future' is from 'dart:async'.
+//       /*@returnType=FutureOr<Future<List<int*>*>*>**/ (/*@type=int**/ x) => /*@typeArgs=dynamic*/ []);
+//                                                                                                   ^
+//
+// pkg/front_end/testcases/inference/future_then_explicit_future.dart:16:25: Error: A value of type 'Future<Future<List<int>>>' can't be assigned to a variable of type 'Future<List<int>>'.
+//  - 'Future' is from 'dart:async'.
+//  - 'List' is from 'dart:core'.
+//   Future<List<int>> y = x;
+//                         ^
+//
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "dart:async";
+
+static method m1() → dynamic {
+  asy::Future<core::int*>* f;
+  asy::Future<asy::Future<core::List<core::int*>*>*>* x = f.{asy::Future::then}<asy::Future<core::List<core::int*>*>*>((core::int* x) → FutureOr<asy::Future<core::List<core::int*>*>*>* => invalid-expression "pkg/front_end/testcases/inference/future_then_explicit_future.dart:15:99: Error: A value of type 'List<dynamic>' can't be assigned to a variable of type 'FutureOr<Future<List<int>>>'.
+ - 'List' is from 'dart:core'.
+ - 'Future' is from 'dart:async'.
+      /*@returnType=FutureOr<Future<List<int*>*>*>**/ (/*@type=int**/ x) => /*@typeArgs=dynamic*/ []);
+                                                                                                  ^" in <dynamic>[] as{TypeError} FutureOr<asy::Future<core::List<core::int*>*>*>*){((core::int*) →* FutureOr<asy::Future<core::List<core::int*>*>*>*, {onError: core::Function*}) →* asy::Future<asy::Future<core::List<core::int*>*>*>*};
+  asy::Future<core::List<core::int*>*>* y = invalid-expression "pkg/front_end/testcases/inference/future_then_explicit_future.dart:16:25: Error: A value of type 'Future<Future<List<int>>>' can't be assigned to a variable of type 'Future<List<int>>'.
+ - 'Future' is from 'dart:async'.
+ - 'List' is from 'dart:core'.
+  Future<List<int>> y = x;
+                        ^" in x as{TypeError} asy::Future<core::List<core::int*>*>*;
+}
+static method m2() → dynamic {
+  asy::Future<core::int*>* f;
+  asy::Future<core::List<core::int*>*>* x = f.{asy::Future::then}<core::List<core::int*>*>((core::int* x) → core::List<core::int*>* => <core::int*>[]){((core::int*) →* FutureOr<core::List<core::int*>*>*, {onError: core::Function*}) →* asy::Future<core::List<core::int*>*>*};
+  asy::Future<core::List<core::int*>*>* y = x;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/future_then_ifNull.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_ifNull.dart.weak.modular.expect
new file mode 100644
index 0000000..39e82e2
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_ifNull.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method test() → void {
+  self::MyFuture<core::int*>* f;
+  asy::Future<core::int*>* t1 = f.{self::MyFuture::then}<core::int*>((core::int* x) → asy::Future<core::int*>* async => let final core::int* #t1 = x in #t1 == null ?{core::int*} await asy::Future::value<core::int*>(3) : #t1){((core::int*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t2 = f.{self::MyFuture::then}<core::int*>((core::int* x) → FutureOr<core::int*>* async {
+    return (let final core::int* #t2 = await x in #t2 == null ?{core::Object*} asy::Future::value<core::int*>(3) : #t2) as{TypeError} FutureOr<core::int*>*;
+  }){((core::int*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t5 = f.{self::MyFuture::then}<core::int*>((core::int* x) → FutureOr<core::int*>* => (let final core::int* #t3 = x in #t3 == null ?{core::Object*} asy::Future::value<core::int*>(3) : #t3) as{TypeError} FutureOr<core::int*>*){((core::int*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+  asy::Future<core::int*>* t6 = f.{self::MyFuture::then}<core::int*>((core::int* x) → FutureOr<core::int*>* {
+    return (let final core::int* #t4 = x in #t4 == null ?{core::Object*} asy::Future::value<core::int*>(3) : #t4) as{TypeError} FutureOr<core::int*>*;
+  }){((core::int*) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..ac37ff3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_upwards.dart.weak.modular.expect
@@ -0,0 +1,67 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/future_then_upwards.dart:21:49: Error: A value of type 'MyFuture<double>' can't be assigned to a variable of type 'Future<int>'.
+//  - 'MyFuture' is from 'pkg/front_end/testcases/inference/future_then_upwards.dart'.
+//  - 'Future' is from 'dart:async'.
+//   Future<int> f2 = /*error:INVALID_ASSIGNMENT*/ f;
+//                                                 ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method main() → void {
+  self::MyFuture<core::double*>* f = self::foo().{self::MyFuture::then}<core::double*>((dynamic _) → core::double* => 2.3){((dynamic) →* FutureOr<core::double*>*, {onError: core::Function*}) →* self::MyFuture<core::double*>*};
+  asy::Future<core::int*>* f2 = invalid-expression "pkg/front_end/testcases/inference/future_then_upwards.dart:21:49: Error: A value of type 'MyFuture<double>' can't be assigned to a variable of type 'Future<int>'.
+ - 'MyFuture' is from 'pkg/front_end/testcases/inference/future_then_upwards.dart'.
+ - 'Future' is from 'dart:async'.
+  Future<int> f2 = /*error:INVALID_ASSIGNMENT*/ f;
+                                                ^" in f as{TypeError} asy::Future<core::int*>*;
+  asy::Future<core::num*>* f3 = self::foo().{self::MyFuture::then}<core::double*>((dynamic _) → core::double* => 2.3){((dynamic) →* FutureOr<core::double*>*, {onError: core::Function*}) →* self::MyFuture<core::double*>*} as asy::Future<core::double*>*;
+}
+static method foo() → self::MyFuture<dynamic>*
+  return new self::MyFuture::value<core::int*>(1);
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_upwards_2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_upwards_2.dart.weak.modular.expect
new file mode 100644
index 0000000..e071ff7
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_upwards_2.dart.weak.modular.expect
@@ -0,0 +1,65 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/future_then_upwards_2.dart:21:51: Error: A value of type 'MyFuture<double>' can't be assigned to a variable of type 'MyFuture<int>'.
+//  - 'MyFuture' is from 'pkg/front_end/testcases/inference/future_then_upwards_2.dart'.
+//   MyFuture<int> f2 = /*error:INVALID_ASSIGNMENT*/ f;
+//                                                   ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method main() → void {
+  self::MyFuture<core::double*>* f = self::foo().{self::MyFuture::then}<core::double*>((dynamic _) → core::double* => 2.3){((dynamic) →* FutureOr<core::double*>*, {onError: core::Function*}) →* self::MyFuture<core::double*>*};
+  self::MyFuture<core::int*>* f2 = invalid-expression "pkg/front_end/testcases/inference/future_then_upwards_2.dart:21:51: Error: A value of type 'MyFuture<double>' can't be assigned to a variable of type 'MyFuture<int>'.
+ - 'MyFuture' is from 'pkg/front_end/testcases/inference/future_then_upwards_2.dart'.
+  MyFuture<int> f2 = /*error:INVALID_ASSIGNMENT*/ f;
+                                                  ^" in f as{TypeError} self::MyFuture<core::int*>*;
+  self::MyFuture<core::num*>* f3 = self::foo().{self::MyFuture::then}<core::double*>((dynamic _) → core::double* => 2.3){((dynamic) →* FutureOr<core::double*>*, {onError: core::Function*}) →* self::MyFuture<core::double*>*} as self::MyFuture<core::double*>*;
+}
+static method foo() → self::MyFuture<dynamic>*
+  return new self::MyFuture::value<core::int*>(1);
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_upwards_3.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_upwards_3.dart.weak.modular.expect
new file mode 100644
index 0000000..c45ca17
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_upwards_3.dart.weak.modular.expect
@@ -0,0 +1,66 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/future_then_upwards_3.dart:21:49: Error: A value of type 'Future<double>' can't be assigned to a variable of type 'Future<int>'.
+//  - 'Future' is from 'dart:async'.
+//   Future<int> f2 = /*error:INVALID_ASSIGNMENT*/ f;
+//                                                 ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(self::MyFuture::T* x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method test() → void {
+  asy::Future<core::double*>* f = self::foo().{asy::Future::then}<core::double*>((dynamic _) → core::double* => 2.3){((dynamic) →* FutureOr<core::double*>*, {onError: core::Function*}) →* asy::Future<core::double*>*};
+  asy::Future<core::int*>* f2 = invalid-expression "pkg/front_end/testcases/inference/future_then_upwards_3.dart:21:49: Error: A value of type 'Future<double>' can't be assigned to a variable of type 'Future<int>'.
+ - 'Future' is from 'dart:async'.
+  Future<int> f2 = /*error:INVALID_ASSIGNMENT*/ f;
+                                                ^" in f as{TypeError} asy::Future<core::int*>*;
+  asy::Future<core::num*>* f3 = self::foo().{asy::Future::then}<core::double*>((dynamic _) → core::double* => 2.3){((dynamic) →* FutureOr<core::double*>*, {onError: core::Function*}) →* asy::Future<core::double*>*} as asy::Future<core::double*>*;
+}
+static method foo() → asy::Future<dynamic>*
+  return asy::Future::value<core::int*>(1);
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_then_upwards_from_block.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_then_upwards_from_block.dart.weak.modular.expect
new file mode 100644
index 0000000..3acce35
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_then_upwards_from_block.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library test;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "dart:async";
+
+static method test() → dynamic {
+  asy::Future<core::int*>* base;
+  asy::Future<core::bool*>* f = base.{asy::Future::then}<core::bool*>((core::int* x) → core::bool* {
+    return x =={core::num::==}{(core::Object*) →* core::bool*} 0;
+  }){((core::int*) →* FutureOr<core::bool*>*, {onError: core::Function*}) →* asy::Future<core::bool*>*};
+  asy::Future<core::bool*>* g = base.{asy::Future::then}<core::bool*>((core::int* x) → core::bool* => x =={core::num::==}{(core::Object*) →* core::bool*} 0){((core::int*) →* FutureOr<core::bool*>*, {onError: core::Function*}) →* asy::Future<core::bool*>*};
+  asy::Future<core::bool*>* b = f;
+  b = g;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/future_union_async_conditional.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_union_async_conditional.dart.weak.modular.expect
new file mode 100644
index 0000000..dcdc4a1
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_union_async_conditional.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(dynamic x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method g1(core::bool* x) → asy::Future<core::int*>* async {
+  return (x ?{core::Object*} 42 : asy::Future::value<core::int*>(42)) as{TypeError} FutureOr<core::int*>*;
+}
+static method g2(core::bool* x) → asy::Future<core::int*>* async 
+  return (x ?{core::Object*} 42 : asy::Future::value<core::int*>(42)) as{TypeError} FutureOr<core::int*>*;
+static method g3(core::bool* x) → asy::Future<core::int*>* async {
+  core::Object* y = x ?{core::Object*} 42 : asy::Future::value<core::int*>(42);
+  return y as{TypeError} FutureOr<core::int*>*;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_union_async_conditional_2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_union_async_conditional_2.dart.weak.modular.expect
new file mode 100644
index 0000000..1c0791d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_union_async_conditional_2.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value(dynamic x) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static method g1(core::bool* x) → asy::Future<core::int*>* async {
+  return (x ?{core::Object*} 42 : new self::MyFuture::value<core::int*>(42)) as{TypeError} FutureOr<core::int*>*;
+}
+static method g2(core::bool* x) → asy::Future<core::int*>* async 
+  return (x ?{core::Object*} 42 : new self::MyFuture::value<core::int*>(42)) as{TypeError} FutureOr<core::int*>*;
+static method g3(core::bool* x) → asy::Future<core::int*>* async {
+  core::Object* y = x ?{core::Object*} 42 : new self::MyFuture::value<dynamic>(42);
+  return y as{TypeError} FutureOr<core::int*>*;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_union_downwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_union_downwards.dart.weak.modular.expect
new file mode 100644
index 0000000..ccef45f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_union_downwards.dart.weak.modular.expect
@@ -0,0 +1,66 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/future_union_downwards.dart:21:47: Error: The argument type 'String' can't be assigned to the parameter type 'FutureOr<int>'.
+//         new /*@ typeArgs=int* */ Future.value('hi'));
+//                                               ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value([dynamic x = #C1]) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static field self::MyFuture<dynamic>* f;
+static field asy::Future<core::int*>* t1 = self::f.{self::MyFuture::then}<core::int*>((dynamic _) → asy::Future<core::int*>* => asy::Future::value<core::int*>(invalid-expression "pkg/front_end/testcases/inference/future_union_downwards.dart:21:47: Error: The argument type 'String' can't be assigned to the parameter type 'FutureOr<int>'.
+        new /*@ typeArgs=int* */ Future.value('hi'));
+                                              ^" in "hi" as{TypeError} FutureOr<core::int*>?)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+static field asy::Future<core::List<core::int*>*>* t2 = self::f.{self::MyFuture::then}<core::List<core::int*>*>((dynamic _) → core::List<core::int*>* => <core::int*>[3]){((dynamic) →* FutureOr<core::List<core::int*>*>*, {onError: core::Function*}) →* self::MyFuture<core::List<core::int*>*>*};
+static method g2() → asy::Future<core::List<core::int*>*>* async {
+  return <core::int*>[3];
+}
+static method g3() → asy::Future<core::List<core::int*>*>* async {
+  return asy::Future::value<core::List<core::int*>*>(<core::int*>[3]);
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_union_downwards_2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_union_downwards_2.dart.weak.modular.expect
new file mode 100644
index 0000000..09bd9c2
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_union_downwards_2.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value([dynamic x = #C1]) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static field self::MyFuture<dynamic>* f;
+static field asy::Future<core::int*>* t1 = self::f.{self::MyFuture::then}<core::int*>((dynamic _) → self::MyFuture<core::int*>* => new self::MyFuture::value<core::int*>("hi")){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* self::MyFuture<core::int*>*};
+static field asy::Future<core::List<core::int*>*>* t2 = self::f.{self::MyFuture::then}<core::List<core::int*>*>((dynamic _) → core::List<core::int*>* => <core::int*>[3]){((dynamic) →* FutureOr<core::List<core::int*>*>*, {onError: core::Function*}) →* self::MyFuture<core::List<core::int*>*>*};
+static method g2() → asy::Future<core::List<core::int*>*>* async {
+  return <core::int*>[3];
+}
+static method g3() → asy::Future<core::List<core::int*>*>* async {
+  return new self::MyFuture::value<core::List<core::int*>*>(<core::int*>[3]);
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_union_downwards_3.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_union_downwards_3.dart.weak.modular.expect
new file mode 100644
index 0000000..36b2fa5
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_union_downwards_3.dart.weak.modular.expect
@@ -0,0 +1,66 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/future_union_downwards_3.dart:21:47: Error: The argument type 'String' can't be assigned to the parameter type 'FutureOr<int>'.
+//         new /*@ typeArgs=int* */ Future.value('hi'));
+//                                               ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value([dynamic x = #C1]) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static field asy::Future<dynamic>* f;
+static field asy::Future<core::int*>* t1 = self::f.{asy::Future::then}<core::int*>((dynamic _) → asy::Future<core::int*>* => asy::Future::value<core::int*>(invalid-expression "pkg/front_end/testcases/inference/future_union_downwards_3.dart:21:47: Error: The argument type 'String' can't be assigned to the parameter type 'FutureOr<int>'.
+        new /*@ typeArgs=int* */ Future.value('hi'));
+                                              ^" in "hi" as{TypeError} FutureOr<core::int*>?)){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+static field asy::Future<core::List<core::int*>*>* t2 = self::f.{asy::Future::then}<core::List<core::int*>*>((dynamic _) → core::List<core::int*>* => <core::int*>[3]){((dynamic) →* FutureOr<core::List<core::int*>*>*, {onError: core::Function*}) →* asy::Future<core::List<core::int*>*>*};
+static method g2() → asy::Future<core::List<core::int*>*>* async {
+  return <core::int*>[3];
+}
+static method g3() → asy::Future<core::List<core::int*>*>* async {
+  return asy::Future::value<core::List<core::int*>*>(<core::int*>[3]);
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_union_downwards_4.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_union_downwards_4.dart.weak.modular.expect
new file mode 100644
index 0000000..5ecc3e7
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_union_downwards_4.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class MyFuture<T extends core::Object* = dynamic> extends core::Object implements asy::Future<self::MyFuture::T*> {
+  constructor •() → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  constructor value([dynamic x = #C1]) → self::MyFuture<self::MyFuture::T*>*
+    : super core::Object::•() {}
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  method then<S extends core::Object* = dynamic>((self::MyFuture::T*) →* FutureOr<self::MyFuture::then::S*>* f, {core::Function* onError = #C1}) → self::MyFuture<self::MyFuture::then::S*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method catchError(core::Function* onError, {(core::Object*) →* core::bool* test = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method whenComplete(() →* FutureOr<void>* action) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+  no-such-method-forwarder method asStream() → asy::Stream<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C8, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Stream<self::MyFuture::T*>*;
+  no-such-method-forwarder method timeout(core::Duration* timeLimit, {covariant-by-class () →* FutureOr<self::MyFuture::T*>* onTimeout = #C1}) → asy::Future<self::MyFuture::T*>*
+    return this.{self::MyFuture::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onTimeout}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} asy::Future<self::MyFuture::T*>*;
+}
+static field asy::Future<dynamic>* f;
+static field asy::Future<core::int*>* t1 = self::f.{asy::Future::then}<core::int*>((dynamic _) → self::MyFuture<core::int*>* => new self::MyFuture::value<core::int*>("hi")){((dynamic) →* FutureOr<core::int*>*, {onError: core::Function*}) →* asy::Future<core::int*>*};
+static field asy::Future<core::List<core::int*>*>* t2 = self::f.{asy::Future::then}<core::List<core::int*>*>((dynamic _) → core::List<core::int*>* => <core::int*>[3]){((dynamic) →* FutureOr<core::List<core::int*>*>*, {onError: core::Function*}) →* asy::Future<core::List<core::int*>*>*};
+static method g2() → asy::Future<core::List<core::int*>*>* async {
+  return <core::int*>[3];
+}
+static method g3() → asy::Future<core::List<core::int*>*>* async {
+  return new self::MyFuture::value<core::List<core::int*>*>(<core::int*>[3]);
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #asStream
+  #C8 = <dynamic>[]
+  #C9 = #timeout
+  #C10 = #onTimeout
+}
diff --git a/pkg/front_end/testcases/inference/future_union_downwards_generic_method_with_future_return.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_union_downwards_generic_method_with_future_return.dart.weak.modular.expect
new file mode 100644
index 0000000..05e3e74
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_union_downwards_generic_method_with_future_return.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo() → dynamic async {
+  asy::Future<core::List<self::A*>*>* f1 = null;
+  asy::Future<core::List<self::A*>*>* f2 = null;
+  core::List<core::List<self::A*>*>* merged = await asy::Future::wait<core::List<self::A*>*>(<asy::Future<core::List<self::A*>*>*>[f1, f2]);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/future_union_downwards_generic_method_with_generic_return.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_union_downwards_generic_method_with_generic_return.dart.weak.modular.expect
new file mode 100644
index 0000000..8b0d132
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_union_downwards_generic_method_with_generic_return.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+static method id<T extends core::Object* = dynamic>(self::id::T* x) → self::id::T*
+  return x;
+static method test() → dynamic async {
+  asy::Future<core::String*>* f;
+  core::String* s = await self::id<FutureOr<core::String*>*>(f);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/future_union_upwards_generic_methods.dart.weak.modular.expect b/pkg/front_end/testcases/inference/future_union_upwards_generic_methods.dart.weak.modular.expect
new file mode 100644
index 0000000..f663f65
--- /dev/null
+++ b/pkg/front_end/testcases/inference/future_union_upwards_generic_methods.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C extends self::A {
+  synthetic constructor •() → self::C*
+    : super self::A::•()
+    ;
+}
+static method main() → dynamic async {
+  asy::Future<self::B*>* b = asy::Future::value<self::B*>(new self::B::•());
+  asy::Future<self::C*>* c = asy::Future::value<self::C*>(new self::C::•());
+  core::List<asy::Future<self::A*>*>* lll = <asy::Future<self::A*>*>[b, c];
+  core::List<self::A*>* result = await asy::Future::wait<self::A*>(lll);
+  core::List<self::A*>* result2 = await asy::Future::wait<self::A*>(<asy::Future<self::A*>*>[b, c]);
+  core::List<self::A*>* list = result;
+  list = result2;
+}
diff --git a/pkg/front_end/testcases/inference/generator_closure.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generator_closure.dart.weak.modular.expect
new file mode 100644
index 0000000..c703bed
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generator_closure.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library test;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "dart:async";
+
+static method foo(() →* asy::Stream<core::int*>* values) → void {}
+static method main() → void {
+  self::foo(() → asy::Stream<core::int*>* async* {
+    yield 0;
+    yield 1;
+  });
+}
diff --git a/pkg/front_end/testcases/inference/generic_functions_return_typedef.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_functions_return_typedef.dart.weak.modular.expect
new file mode 100644
index 0000000..b6875d1
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_functions_return_typedef.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef ToValue<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+static method main() → dynamic {
+  function f<T extends core::Object* = dynamic>(T* x) → (T*) →* void
+    return null;
+  (core::int*) →* void x = f<core::int*>(42){(core::int*) →* (core::int*) →* void};
+  (core::int*) →* void y = f<core::int*>(42){(core::int*) →* (core::int*) →* void};
+  (core::int*) →* void takesInt = x;
+  takesInt = y;
+}
diff --git a/pkg/front_end/testcases/inference/generic_methods_basic_downward_inference.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_basic_downward_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..421c4af
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_basic_downward_inference.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method f<S extends core::Object* = dynamic, T extends core::Object* = dynamic>(self::f::S* s) → self::f::T*
+  return null;
+static method main() → dynamic {
+  core::String* x = self::f<core::int*, core::String*>(42);
+  core::String* y = #C1<core::int*, core::String*>(42){(core::int*) →* core::String*};
+}
+
+constants  {
+  #C1 = static-tearoff self::f
+}
diff --git a/pkg/front_end/testcases/inference/generic_methods_correctly_recognize_generic_upper_bound.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_correctly_recognize_generic_upper_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..3871d0a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_correctly_recognize_generic_upper_bound.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/generic_methods_correctly_recognize_generic_upper_bound.dart:26:79: Error: Inferred type argument 'int' doesn't conform to the bound 'String' of the type variable 'U' on 'Foo<String>.method'.
+//  - 'Foo' is from 'pkg/front_end/testcases/inference/generic_methods_correctly_recognize_generic_upper_bound.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//       . /*error:COULD_NOT_INFER*/ /*@ typeArgs=int* */ /*@target=Foo.method*/ method(
+//                                                                               ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo<T extends core::Pattern*> extends core::Object {
+  synthetic constructor •() → self::Foo<self::Foo::T*>*
+    : super core::Object::•()
+    ;
+  method method<covariant-by-class U extends self::Foo::T*>(self::Foo::method::U* u) → self::Foo::method::U*
+    return u;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::Foo::•<core::String*>().{self::Foo::method}<core::int*>(42){(core::int*) →* core::int*};
+}
diff --git a/pkg/front_end/testcases/inference/generic_methods_dart_math_min_max.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_dart_math_min_max.dart.weak.modular.expect
new file mode 100644
index 0000000..9c23381
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_dart_math_min_max.dart.weak.modular.expect
@@ -0,0 +1,54 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/generic_methods_dart_math_min_max.dart:28:35: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+//       /*@ typeArgs=int* */ max(1, 2.0));
+//                                   ^
+//
+// pkg/front_end/testcases/inference/generic_methods_dart_math_min_max.dart:30:35: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+//       /*@ typeArgs=int* */ min(1, 2.0));
+//                                   ^
+//
+// pkg/front_end/testcases/inference/generic_methods_dart_math_min_max.dart:37:37: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//   printInt(/*@ typeArgs=int* */ min("hi", "there"));
+//                                     ^
+//
+// pkg/front_end/testcases/inference/generic_methods_dart_math_min_max.dart:37:43: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//   printInt(/*@ typeArgs=int* */ min("hi", "there"));
+//                                           ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:math" as math;
+
+import "dart:math";
+
+static method printInt(core::int* x) → void
+  return core::print(x);
+static method printDouble(core::double* x) → void
+  return core::print(x);
+static method myMax(core::num* x, core::num* y) → core::num*
+  return math::max<core::num*>(x, y);
+static method f() → dynamic {
+  self::printInt(math::max<core::int*>(1, 2));
+  self::printInt(math::min<core::int*>(1, 2));
+  self::printDouble(math::max<core::double*>(1.0, 2.0));
+  self::printDouble(math::min<core::double*>(1.0, 2.0));
+  self::printInt(self::myMax(1, 2) as{TypeError} core::int*);
+  self::printInt(self::myMax(1, 2) as core::int*);
+  self::printInt(math::max<core::int*>(1, invalid-expression "pkg/front_end/testcases/inference/generic_methods_dart_math_min_max.dart:28:35: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+      /*@ typeArgs=int* */ max(1, 2.0));
+                                  ^" in 2.0 as{TypeError} core::int*));
+  self::printInt(math::min<core::int*>(1, invalid-expression "pkg/front_end/testcases/inference/generic_methods_dart_math_min_max.dart:30:35: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+      /*@ typeArgs=int* */ min(1, 2.0));
+                                  ^" in 2.0 as{TypeError} core::int*));
+  self::printDouble(math::max<core::double*>(1.0, 2.0));
+  self::printDouble(math::min<core::double*>(1.0, 2.0));
+  self::printInt(math::min<core::int*>(invalid-expression "pkg/front_end/testcases/inference/generic_methods_dart_math_min_max.dart:37:37: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+  printInt(/*@ typeArgs=int* */ min(\"hi\", \"there\"));
+                                    ^" in "hi" as{TypeError} core::int*, invalid-expression "pkg/front_end/testcases/inference/generic_methods_dart_math_min_max.dart:37:43: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+  printInt(/*@ typeArgs=int* */ min(\"hi\", \"there\"));
+                                          ^" in "there" as{TypeError} core::int*));
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/generic_methods_do_not_infer_invalid_override_of_generic_method.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_do_not_infer_invalid_override_of_generic_method.dart.weak.modular.expect
new file mode 100644
index 0000000..6c102fe
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_do_not_infer_invalid_override_of_generic_method.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/generic_methods_do_not_infer_invalid_override_of_generic_method.dart:13:3: Error: Can't infer types for 'm' as the overridden members don't have a combined signature.
+// Try adding explicit types.
+//   m(x) => x;
+//   ^
+// pkg/front_end/testcases/inference/generic_methods_do_not_infer_invalid_override_of_generic_method.dart:9:5: Context: This is one of the overridden members.
+//   T m<T>(T x) => x;
+//     ^
+//
+// pkg/front_end/testcases/inference/generic_methods_do_not_infer_invalid_override_of_generic_method.dart:13:3: Error: Declared type variables of 'D.m' doesn't match those on overridden method 'C.m'.
+//   m(x) => x;
+//   ^
+// pkg/front_end/testcases/inference/generic_methods_do_not_infer_invalid_override_of_generic_method.dart:9:5: Context: This is the overridden method ('m').
+//   T m<T>(T x) => x;
+//     ^
+//
+// pkg/front_end/testcases/inference/generic_methods_do_not_infer_invalid_override_of_generic_method.dart:18:73: Error: Expected 0 type arguments.
+//       . /*error:WRONG_NUMBER_OF_TYPE_ARGUMENTS_METHOD*/ /*@target=D.m*/ m<int>(
+//                                                                         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method m<T extends core::Object* = dynamic>(self::C::m::T* x) → self::C::m::T*
+    return x;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method m(invalid-type x) → invalid-type
+    return x;
+}
+static method main() → dynamic {
+  core::int* y = invalid-expression "pkg/front_end/testcases/inference/generic_methods_do_not_infer_invalid_override_of_generic_method.dart:18:73: Error: Expected 0 type arguments.
+      . /*error:WRONG_NUMBER_OF_TYPE_ARGUMENTS_METHOD*/ /*@target=D.m*/ m<int>(
+                                                                        ^" in new self::D::•().{self::D::m}{<inapplicable>}.<core::int*>(42){(invalid-type) →* invalid-type};
+  core::print(y);
+}
diff --git a/pkg/front_end/testcases/inference/generic_methods_downwards_inference_affects_arguments.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_downwards_inference_affects_arguments.dart.weak.modular.expect
new file mode 100644
index 0000000..79f41c9
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_downwards_inference_affects_arguments.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/generic_methods_downwards_inference_affects_arguments.dart:13:79: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//           /*@ typeArgs=String* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ 42]);
+//                                                                               ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method f<T extends core::Object* = dynamic>(core::List<self::f::T*>* s) → self::f::T*
+  return null;
+static method test() → dynamic {
+  core::String* x = self::f<core::String*>(<core::String*>["hi"]);
+  core::String* y = self::f<core::String*>(<core::String*>[invalid-expression "pkg/front_end/testcases/inference/generic_methods_downwards_inference_affects_arguments.dart:13:79: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+          /*@ typeArgs=String* */ [/*error:LIST_ELEMENT_TYPE_NOT_ASSIGNABLE*/ 42]);
+                                                                              ^" in 42 as{TypeError} core::String*]);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/generic_methods_downwards_inference_fold.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_downwards_inference_fold.dart.weak.modular.expect
new file mode 100644
index 0000000..b0966cb
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_downwards_inference_fold.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  core::List<core::int*>* o;
+  core::int* y = o.{core::Iterable::fold}<core::int*>(0, (core::int* x, core::int* y) → core::int* => x.{core::num::+}(y){(core::num*) →* core::int*}){(core::int*, (core::int*, core::int*) →* core::int*) →* core::int*};
+  dynamic z = o.{core::Iterable::fold}<dynamic>(0, (dynamic x, core::int* y) → dynamic => x{dynamic}.+(y)){(dynamic, (dynamic, core::int*) →* dynamic) →* dynamic};
+  y = z as{TypeError,ForDynamic} core::int*;
+}
+static method functionExpressionInvocation() → void {
+  core::List<core::int*>* o;
+  core::int* y = o.{core::Iterable::fold}{<T extends core::Object* = dynamic>(T*, (T*, core::int*) →* T*) →* T*}<core::int*>(0, (core::int* x, core::int* y) → core::int* => x.{core::num::+}(y){(core::num*) →* core::int*}){(core::int*, (core::int*, core::int*) →* core::int*) →* core::int*};
+  dynamic z = o.{core::Iterable::fold}{<T extends core::Object* = dynamic>(T*, (T*, core::int*) →* T*) →* T*}<dynamic>(0, (dynamic x, core::int* y) → dynamic => x{dynamic}.+(y)){(dynamic, (dynamic, core::int*) →* dynamic) →* dynamic};
+  y = z as{TypeError,ForDynamic} core::int*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/generic_methods_handle_override_of_non_generic_with_generic.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_handle_override_of_non_generic_with_generic.dart.weak.modular.expect
new file mode 100644
index 0000000..7241ba2
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_handle_override_of_non_generic_with_generic.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/generic_methods_handle_override_of_non_generic_with_generic.dart:14:5: Error: Declared type variables of 'D.m' doesn't match those on overridden method 'C.m'.
+//   T m<T>(T x) => x;
+//     ^
+// pkg/front_end/testcases/inference/generic_methods_handle_override_of_non_generic_with_generic.dart:9:3: Context: This is the overridden method ('m').
+//   m(x) => x;
+//   ^
+//
+// pkg/front_end/testcases/inference/generic_methods_handle_override_of_non_generic_with_generic.dart:14:12: Error: The parameter 'x' of the method 'D.m' has type 'T', which does not match the corresponding type, 'dynamic', in the overridden method, 'C.m'.
+// Change to a supertype of 'dynamic', or, for a covariant parameter, a subtype.
+//   T m<T>(T x) => x;
+//            ^
+// pkg/front_end/testcases/inference/generic_methods_handle_override_of_non_generic_with_generic.dart:9:3: Context: This is the overridden method ('m').
+//   m(x) => x;
+//   ^
+//
+// pkg/front_end/testcases/inference/generic_methods_handle_override_of_non_generic_with_generic.dart:15:5: Error: Declared type variables of 'D.g' doesn't match those on overridden method 'C.g'.
+//   T g<T>(T x) => x;
+//     ^
+// pkg/front_end/testcases/inference/generic_methods_handle_override_of_non_generic_with_generic.dart:10:11: Context: This is the overridden method ('g').
+//   dynamic g(int x) => x;
+//           ^
+//
+// pkg/front_end/testcases/inference/generic_methods_handle_override_of_non_generic_with_generic.dart:15:12: Error: The parameter 'x' of the method 'D.g' has type 'T', which does not match the corresponding type, 'int', in the overridden method, 'C.g'.
+// Change to a supertype of 'int', or, for a covariant parameter, a subtype.
+//   T g<T>(T x) => x;
+//            ^
+// pkg/front_end/testcases/inference/generic_methods_handle_override_of_non_generic_with_generic.dart:10:11: Context: This is the overridden method ('g').
+//   dynamic g(int x) => x;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method m(dynamic x) → dynamic
+    return x;
+  method g(core::int* x) → dynamic
+    return x;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method m<T extends core::Object* = dynamic>(self::D::m::T* x) → self::D::m::T*
+    return x;
+  method g<T extends core::Object* = dynamic>(self::D::g::T* x) → self::D::g::T*
+    return x;
+}
+static method main() → dynamic {
+  core::int* y = (new self::D::•() as self::C*).{self::C::m}(42){(dynamic) →* dynamic} as{TypeError,ForDynamic} core::int*;
+  core::print(y);
+}
diff --git a/pkg/front_end/testcases/inference/generic_methods_infer_generic_function_parameter_type.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_infer_generic_function_parameter_type.dart.weak.modular.expect
new file mode 100644
index 0000000..6d57e34
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_infer_generic_function_parameter_type.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant V extends core::Object* = dynamic> = (V*) →* void;
+class C<T extends core::Object* = dynamic> extends self::D<self::C::T*> {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super self::D::•()
+    ;
+  method f<U extends core::Object* = dynamic>(self::C::f::U* x) → (self::C::f::U*) →* void {}
+}
+class D<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  method f<U extends core::Object* = dynamic>(self::D::f::U* u) → (self::D::f::U*) →* void
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/generic_methods_infer_generic_function_parameter_type2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_infer_generic_function_parameter_type2.dart.weak.modular.expect
new file mode 100644
index 0000000..58ca700
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_infer_generic_function_parameter_type2.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef G<V extends core::Object* = dynamic> = () →* core::List<V*>*;
+class C<T extends core::Object* = dynamic> extends self::D<self::C::T*> {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super self::D::•()
+    ;
+  method f<U extends core::Object* = dynamic>(() →* core::List<self::C::f::U*>* g) → void
+    return null;
+}
+abstract class D<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  abstract method f<U extends core::Object* = dynamic>(() →* core::List<self::D::f::U*>* g) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/generic_methods_infer_generic_function_return_type.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_infer_generic_function_return_type.dart.weak.modular.expect
new file mode 100644
index 0000000..60d43bc
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_infer_generic_function_return_type.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<V extends core::Object* = dynamic> = () →* V*;
+class C<T extends core::Object* = dynamic> extends self::D<self::C::T*> {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super self::D::•()
+    ;
+  method f<U extends core::Object* = dynamic>(self::C::f::U* x) → () →* self::C::f::U* {}
+}
+class D<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  method f<U extends core::Object* = dynamic>(self::D::f::U* u) → () →* self::D::f::U*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart.weak.modular.expect
new file mode 100644
index 0000000..a033796
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart.weak.modular.expect
@@ -0,0 +1,189 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:26:70: Error: Inferred type argument 'Object' doesn't conform to the bound 'num' of the type variable 'T' on 'T Function<T extends num>(T, T)'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   takeOOI(/*error:COULD_NOT_INFER,error:INVALID_CAST_FUNCTION*/ math.max);
+//                                                                      ^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:28:73: Error: The argument type 'num Function(num, num)' can't be assigned to the parameter type 'int Function(double, int)'.
+//       /*error:COULD_NOT_INFER,error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ math.max);
+//                                                                         ^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:30:73: Error: The argument type 'num Function(num, num)' can't be assigned to the parameter type 'double Function(int, double)'.
+//       /*error:COULD_NOT_INFER,error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ math.max);
+//                                                                         ^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:31:70: Error: Inferred type argument 'Object' doesn't conform to the bound 'num' of the type variable 'T' on 'T Function<T extends num>(T, T)'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   takeOON(/*error:COULD_NOT_INFER,error:INVALID_CAST_FUNCTION*/ math.max);
+//                                                                      ^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:32:70: Error: Inferred type argument 'Object' doesn't conform to the bound 'num' of the type variable 'T' on 'T Function<T extends num>(T, T)'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   takeOOO(/*error:COULD_NOT_INFER,error:INVALID_CAST_FUNCTION*/ math.max);
+//                                                                      ^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:45:65: Error: Inferred type argument 'Object' doesn't conform to the bound 'num' of the type variable 'T' on 'T Function<T extends num>(T, T)'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   takeOOI(/*error:COULD_NOT_INFER,error:INVALID_CAST_FUNCTION*/ min);
+//                                                                 ^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:46:72: Error: The argument type 'num Function(num, num)' can't be assigned to the parameter type 'int Function(double, int)'.
+//   takeIDI(/*error:COULD_NOT_INFER,error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ min);
+//                                                                        ^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:47:72: Error: The argument type 'num Function(num, num)' can't be assigned to the parameter type 'double Function(int, double)'.
+//   takeDID(/*error:COULD_NOT_INFER,error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ min);
+//                                                                        ^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:48:65: Error: Inferred type argument 'Object' doesn't conform to the bound 'num' of the type variable 'T' on 'T Function<T extends num>(T, T)'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   takeOON(/*error:COULD_NOT_INFER,error:INVALID_CAST_FUNCTION*/ min);
+//                                                                 ^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:49:65: Error: Inferred type argument 'Object' doesn't conform to the bound 'num' of the type variable 'T' on 'T Function<T extends num>(T, T)'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   takeOOO(/*error:COULD_NOT_INFER,error:INVALID_CAST_FUNCTION*/ min);
+//                                                                 ^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:73:25: Error: Inferred type argument 'Object' doesn't conform to the bound 'num' of the type variable 'T' on 'T Function<T extends num>(T, T)'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//       . /*@target=C.m*/ m);
+//                         ^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:75:25: Error: Inferred type argument 'Object' doesn't conform to the bound 'num' of the type variable 'T' on 'T Function<T extends num>(T, T)'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//       . /*@target=C.m*/ m);
+//                         ^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:82:25: Error: Inferred type argument 'Object' doesn't conform to the bound 'num' of the type variable 'T' on 'T Function<T extends num>(T, T)'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//       . /*@target=C.m*/ m);
+//                         ^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:86:29: Error: The argument type 'num Function(num, num)' can't be assigned to the parameter type 'int Function(double, int)'.
+//           . /*@target=C.m*/ m);
+//                             ^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:89:29: Error: The argument type 'num Function(num, num)' can't be assigned to the parameter type 'double Function(int, double)'.
+//           . /*@target=C.m*/ m);
+//                             ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "dart:math" as math;
+import "dart:math" show min;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method m<T extends core::num*>(self::C::m::T* x, self::C::m::T* y) → self::C::m::T*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  self::takeIII(#C2);
+  self::takeDDD(#C3);
+  self::takeNNN(#C4);
+  self::takeIDN(#C4);
+  self::takeDIN(#C4);
+  self::takeIIN(#C2);
+  self::takeDDN(#C3);
+  self::takeIIO(#C2);
+  self::takeDDO(#C3);
+  self::takeOOI(#C5 as{TypeError} (core::Object*, core::Object*) →* core::int*);
+  self::takeIDI(invalid-expression "pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:28:73: Error: The argument type 'num Function(num, num)' can't be assigned to the parameter type 'int Function(double, int)'.
+      /*error:COULD_NOT_INFER,error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ math.max);
+                                                                        ^" in #C4 as{TypeError} (core::double*, core::int*) →* core::int*);
+  self::takeDID(invalid-expression "pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:30:73: Error: The argument type 'num Function(num, num)' can't be assigned to the parameter type 'double Function(int, double)'.
+      /*error:COULD_NOT_INFER,error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ math.max);
+                                                                        ^" in #C4 as{TypeError} (core::int*, core::double*) →* core::double*);
+  self::takeOON(#C5 as{TypeError} (core::Object*, core::Object*) →* core::num*);
+  self::takeOOO(#C5 as{TypeError} (core::Object*, core::Object*) →* core::num*);
+  self::takeIII(#C7);
+  self::takeDDD(#C8);
+  self::takeNNN(#C9);
+  self::takeIDN(#C9);
+  self::takeDIN(#C9);
+  self::takeIIN(#C7);
+  self::takeDDN(#C8);
+  self::takeIIO(#C7);
+  self::takeDDO(#C8);
+  self::takeOOI(#C10 as{TypeError} (core::Object*, core::Object*) →* core::int*);
+  self::takeIDI(invalid-expression "pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:46:72: Error: The argument type 'num Function(num, num)' can't be assigned to the parameter type 'int Function(double, int)'.
+  takeIDI(/*error:COULD_NOT_INFER,error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ min);
+                                                                       ^" in #C9 as{TypeError} (core::double*, core::int*) →* core::int*);
+  self::takeDID(invalid-expression "pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:47:72: Error: The argument type 'num Function(num, num)' can't be assigned to the parameter type 'double Function(int, double)'.
+  takeDID(/*error:COULD_NOT_INFER,error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ min);
+                                                                       ^" in #C9 as{TypeError} (core::int*, core::double*) →* core::double*);
+  self::takeOON(#C10 as{TypeError} (core::Object*, core::Object*) →* core::num*);
+  self::takeOOO(#C10 as{TypeError} (core::Object*, core::Object*) →* core::num*);
+  self::takeIII(new self::C::•().{self::C::m}{<T extends core::num*>(T*, T*) →* T*}<core::int*>);
+  self::takeDDD(new self::C::•().{self::C::m}{<T extends core::num*>(T*, T*) →* T*}<core::double*>);
+  self::takeNNN(new self::C::•().{self::C::m}{<T extends core::num*>(T*, T*) →* T*}<core::num*>);
+  self::takeIDN(new self::C::•().{self::C::m}{<T extends core::num*>(T*, T*) →* T*}<core::num*>);
+  self::takeDIN(new self::C::•().{self::C::m}{<T extends core::num*>(T*, T*) →* T*}<core::num*>);
+  self::takeIIN(new self::C::•().{self::C::m}{<T extends core::num*>(T*, T*) →* T*}<core::int*>);
+  self::takeDDN(new self::C::•().{self::C::m}{<T extends core::num*>(T*, T*) →* T*}<core::double*>);
+  self::takeIIO(new self::C::•().{self::C::m}{<T extends core::num*>(T*, T*) →* T*}<core::int*>);
+  self::takeDDO(new self::C::•().{self::C::m}{<T extends core::num*>(T*, T*) →* T*}<core::double*>);
+  self::takeOON((new self::C::•().{self::C::m}{<T extends core::num*>(T*, T*) →* T*}<core::Object*>) as{TypeError} (core::Object*, core::Object*) →* core::num*);
+  self::takeOOO((new self::C::•().{self::C::m}{<T extends core::num*>(T*, T*) →* T*}<core::Object*>) as{TypeError} (core::Object*, core::Object*) →* core::num*);
+  self::takeOOI((new self::C::•().{self::C::m}{<T extends core::num*>(T*, T*) →* T*}<core::Object*>) as{TypeError} (core::Object*, core::Object*) →* core::int*);
+  self::takeIDI(invalid-expression "pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:86:29: Error: The argument type 'num Function(num, num)' can't be assigned to the parameter type 'int Function(double, int)'.
+          . /*@target=C.m*/ m);
+                            ^" in (new self::C::•().{self::C::m}{<T extends core::num*>(T*, T*) →* T*}<core::num*>) as{TypeError} (core::double*, core::int*) →* core::int*);
+  self::takeDID(invalid-expression "pkg/front_end/testcases/inference/generic_methods_infer_generic_instantiation.dart:89:29: Error: The argument type 'num Function(num, num)' can't be assigned to the parameter type 'double Function(int, double)'.
+          . /*@target=C.m*/ m);
+                            ^" in (new self::C::•().{self::C::m}{<T extends core::num*>(T*, T*) →* T*}<core::num*>) as{TypeError} (core::int*, core::double*) →* core::double*);
+}
+static method takeIII((core::int*, core::int*) →* core::int* fn) → void {}
+static method takeDDD((core::double*, core::double*) →* core::double* fn) → void {}
+static method takeIDI((core::double*, core::int*) →* core::int* fn) → void {}
+static method takeDID((core::int*, core::double*) →* core::double* fn) → void {}
+static method takeIDN((core::double*, core::int*) →* core::num* fn) → void {}
+static method takeDIN((core::int*, core::double*) →* core::num* fn) → void {}
+static method takeIIN((core::int*, core::int*) →* core::num* fn) → void {}
+static method takeDDN((core::double*, core::double*) →* core::num* fn) → void {}
+static method takeNNN((core::num*, core::num*) →* core::num* fn) → void {}
+static method takeOON((core::Object*, core::Object*) →* core::num* fn) → void {}
+static method takeOOO((core::Object*, core::Object*) →* core::num* fn) → void {}
+static method takeOOI((core::Object*, core::Object*) →* core::int* fn) → void {}
+static method takeIIO((core::int*, core::int*) →* core::Object* fn) → void {}
+static method takeDDO((core::double*, core::double*) →* core::Object* fn) → void {}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff math::max
+  #C2 = instantiation #C1 <core::int*>
+  #C3 = instantiation #C1 <core::double*>
+  #C4 = instantiation #C1 <core::num*>
+  #C5 = instantiation #C1 <core::Object*>
+  #C6 = static-tearoff math::min
+  #C7 = instantiation #C6 <core::int*>
+  #C8 = instantiation #C6 <core::double*>
+  #C9 = instantiation #C6 <core::num*>
+  #C10 = instantiation #C6 <core::Object*>
+}
diff --git a/pkg/front_end/testcases/inference/generic_methods_infer_generic_method_type.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_infer_generic_method_type.dart.weak.modular.expect
new file mode 100644
index 0000000..530ec6a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_infer_generic_method_type.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method m<T extends core::Object* = dynamic>(self::C::m::T* x) → self::C::m::T*
+    return x;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method m<S extends core::Object* = dynamic>(self::D::m::S* x) → self::D::m::S*
+    return x;
+}
+static method main() → dynamic {
+  core::int* y = new self::D::•().{self::D::m}<core::int*>(42){(core::int*) →* core::int*};
+  core::print(y);
+}
diff --git a/pkg/front_end/testcases/inference/generic_methods_infer_js_builtin.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_infer_js_builtin.dart.weak.modular.expect
new file mode 100644
index 0000000..4831a9f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_infer_js_builtin.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+//
+// Problems outside component:
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_js_builtin.dart:9:8: Error: Not found: 'dart:_foreign_helper'
+// import 'dart:_foreign_helper' show JS; // error
+//        ^
+//
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_js_builtin.dart:9:8: Error: Can't access platform private library.
+// import 'dart:_foreign_helper' show JS; // error
+//        ^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_js_builtin.dart:12:14: Error: Method not found: 'JS'.
+//   String x = JS('int', '42'); // error
+//              ^^
+//
+// pkg/front_end/testcases/inference/generic_methods_infer_js_builtin.dart:13:34: Error: Method not found: 'JS'.
+//   var /*@type=invalid-type*/ y = JS<String>('String', '"hello"');
+//                                  ^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "dart:_foreign_helper" show JS;
+
+static method test() → dynamic {
+  core::String* x = invalid-expression "pkg/front_end/testcases/inference/generic_methods_infer_js_builtin.dart:12:14: Error: Method not found: 'JS'.
+  String x = JS('int', '42'); // error
+             ^^";
+  invalid-type y = invalid-expression "pkg/front_end/testcases/inference/generic_methods_infer_js_builtin.dart:13:34: Error: Method not found: 'JS'.
+  var /*@type=invalid-type*/ y = JS<String>('String', '\"hello\"');
+                                 ^^";
+  y = "world";
+  y = 42;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/generic_methods_inference_error.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_inference_error.dart.weak.modular.expect
new file mode 100644
index 0000000..f3dc908
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_inference_error.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/generic_methods_inference_error.dart:13:11: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+//           1.0);
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method f() → void {
+  core::List<core::String*>* y;
+  core::Iterable<core::String*>* x = y.{core::Iterable::map}<core::String*>((core::String* z) → core::String* => invalid-expression "pkg/front_end/testcases/inference/generic_methods_inference_error.dart:13:11: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+          1.0);
+          ^" in 1.0 as{TypeError} core::String*){((core::String*) →* core::String*) →* core::Iterable<core::String*>*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/generic_methods_iterable_and_future.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_iterable_and_future.dart.weak.modular.expect
new file mode 100644
index 0000000..2f4c738
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_iterable_and_future.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/generic_methods_iterable_and_future.dart:23:123: Error: The operator '+' isn't defined for the class 'FutureOr<String>'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//                           /*@ type=int* */ y) => /*info:DYNAMIC_CAST,info:DYNAMIC_INVOKE*/ x /*error:UNDEFINED_OPERATOR*/ +
+//                                                                                                                           ^
+//
+// pkg/front_end/testcases/inference/generic_methods_iterable_and_future.dart:31:111: Error: The argument type 'String Function(String, int)' can't be assigned to the parameter type 'FutureOr<String> Function(FutureOr<String>, int)'.
+//                   /*info:INFERRED_TYPE_CLOSURE,error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ /*@ returnType=String* */ (String
+//                                                                                                               ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+static method make(core::int* x) → asy::Future<core::int*>*
+  return asy::Future::•<core::int*>(() → core::int* => x);
+static method test() → dynamic {
+  core::Iterable<asy::Future<core::int*>*>* list = <core::int*>[1, 2, 3].{core::Iterable::map}<asy::Future<core::int*>*>(#C1){((core::int*) →* asy::Future<core::int*>*) →* core::Iterable<asy::Future<core::int*>*>*};
+  asy::Future<core::List<core::int*>*>* results = asy::Future::wait<core::int*>(list);
+  asy::Future<core::String*>* results2 = results.{asy::Future::then}<core::String*>((core::List<core::int*>* list) → FutureOr<core::String*>* => list.{core::Iterable::fold}<FutureOr<core::String*>*>("", (FutureOr<core::String*>* x, core::int* y) → FutureOr<core::String*>* => invalid-expression "pkg/front_end/testcases/inference/generic_methods_iterable_and_future.dart:23:123: Error: The operator '+' isn't defined for the class 'FutureOr<String>'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+                          /*@ type=int* */ y) => /*info:DYNAMIC_CAST,info:DYNAMIC_INVOKE*/ x /*error:UNDEFINED_OPERATOR*/ +
+                                                                                                                          ^" in x{<unresolved>}.+(y.{core::int::toString}(){() →* core::String*}) as{TypeError,ForDynamic} FutureOr<core::String*>*){(FutureOr<core::String*>*, (FutureOr<core::String*>*, core::int*) →* FutureOr<core::String*>*) →* FutureOr<core::String*>*}){((core::List<core::int*>*) →* FutureOr<core::String*>*, {onError: core::Function*}) →* asy::Future<core::String*>*};
+  asy::Future<core::String*>* results3 = results.{asy::Future::then}<core::String*>((core::List<core::int*>* list) → FutureOr<core::String*>* => list.{core::Iterable::fold}<FutureOr<core::String*>*>("", invalid-expression "pkg/front_end/testcases/inference/generic_methods_iterable_and_future.dart:31:111: Error: The argument type 'String Function(String, int)' can't be assigned to the parameter type 'FutureOr<String> Function(FutureOr<String>, int)'.
+                  /*info:INFERRED_TYPE_CLOSURE,error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ /*@ returnType=String* */ (String
+                                                                                                              ^" in ((core::String* x, core::int* y) → core::String* => x.{core::String::+}(y.{core::int::toString}(){() →* core::String*}){(core::String*) →* core::String*}) as{TypeError} (FutureOr<core::String*>*, core::int*) →* FutureOr<core::String*>*){(FutureOr<core::String*>*, (FutureOr<core::String*>*, core::int*) →* FutureOr<core::String*>*) →* FutureOr<core::String*>*}){((core::List<core::int*>*) →* FutureOr<core::String*>*, {onError: core::Function*}) →* asy::Future<core::String*>*};
+  asy::Future<core::String*>* results4 = results.{asy::Future::then}<core::String*>((core::List<core::int*>* list) → core::String* => list.{core::Iterable::fold}<core::String*>("", (core::String* x, core::int* y) → core::String* => x.{core::String::+}(y.{core::int::toString}(){() →* core::String*}){(core::String*) →* core::String*}){(core::String*, (core::String*, core::int*) →* core::String*) →* core::String*}){((core::List<core::int*>*) →* FutureOr<core::String*>*, {onError: core::Function*}) →* asy::Future<core::String*>*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::make
+}
diff --git a/pkg/front_end/testcases/inference/generic_methods_nested_generic_instantiation.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_nested_generic_instantiation.dart.weak.modular.expect
new file mode 100644
index 0000000..5a1deb3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_nested_generic_instantiation.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+import "dart:math" as math;
+
+class Trace extends core::Object {
+  field core::List<self::Frame*>* frames = <self::Frame*>[];
+  synthetic constructor •() → self::Trace*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Frame extends core::Object {
+  field core::String* location = "";
+  synthetic constructor •() → self::Frame*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::List<self::Trace*>* traces = <self::Trace*>[];
+  core::int* longest = traces.{core::Iterable::map}<core::int*>((self::Trace* trace) → core::int* {
+    return trace.{self::Trace::frames}{core::List<self::Frame*>*}.{core::Iterable::map}<core::int*>((self::Frame* frame) → core::int* => frame.{self::Frame::location}{core::String*}.{core::String::length}{core::int*}){((self::Frame*) →* core::int*) →* core::Iterable<core::int*>*}.{core::Iterable::fold}<core::int*>(0, #C2){(core::int*, (core::int*, core::int*) →* core::int*) →* core::int*};
+  }){((self::Trace*) →* core::int*) →* core::Iterable<core::int*>*}.{core::Iterable::fold}<core::int*>(0, #C2){(core::int*, (core::int*, core::int*) →* core::int*) →* core::int*};
+}
+
+constants  {
+  #C1 = static-tearoff math::max
+  #C2 = instantiation #C1 <core::int*>
+}
diff --git a/pkg/front_end/testcases/inference/generic_methods_uses_greatest_lower_bound.dart.weak.modular.expect b/pkg/front_end/testcases/inference/generic_methods_uses_greatest_lower_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..868f419
--- /dev/null
+++ b/pkg/front_end/testcases/inference/generic_methods_uses_greatest_lower_bound.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F = (core::int*) →* core::Iterable<core::num*>*;
+typedef G = (core::double*) →* core::List<core::int*>*;
+static method generic<T extends core::Object* = dynamic>((self::generic::T*) →* dynamic a, (self::generic::T*) →* dynamic b) → self::generic::T*
+  return null;
+static method main() → dynamic {
+  (core::num*) →* core::List<core::int*>* v = self::generic<(core::num*) →* core::List<core::int*>*>(((core::int*) →* core::Iterable<core::num*>* f) → Null => null, ((core::double*) →* core::List<core::int*>* g) → Null => null);
+}
diff --git a/pkg/front_end/testcases/inference/greatest_closure_multiple_params.dart.weak.modular.expect b/pkg/front_end/testcases/inference/greatest_closure_multiple_params.dart.weak.modular.expect
new file mode 100644
index 0000000..d6bd505
--- /dev/null
+++ b/pkg/front_end/testcases/inference/greatest_closure_multiple_params.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class C<E extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::E*>*
+    : super core::Object::•()
+    ;
+  method sort([(self::C::E*, self::C::E*) →* core::int* compare = #C1]) → void {
+    self::C::sort2<self::C::E*>(this, let final (self::C::E*, self::C::E*) →* core::int* #t1 = compare in #t1 == null ?{(self::C::E*, self::C::E*) →* core::int*} #C2 : #t1);
+  }
+  static method _compareAny(dynamic a, dynamic b) → core::int* {
+    throw "unimplemented";
+  }
+  static method sort2<E extends core::Object* = dynamic>(self::C<self::C::sort2::E*>* a, (self::C::sort2::E*, self::C::sort2::E*) →* core::int* compare) → void {
+    throw "unimplemented";
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = static-tearoff self::C::_compareAny
+}
diff --git a/pkg/front_end/testcases/inference/inconsistent_overrides.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inconsistent_overrides.dart.weak.modular.expect
new file mode 100644
index 0000000..2948381e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inconsistent_overrides.dart.weak.modular.expect
@@ -0,0 +1,89 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/inconsistent_overrides.dart:16:3: Error: Can't infer types for 'f' as the overridden members don't have a combined signature.
+// Try adding explicit types.
+//   f(x, {y}) {}
+//   ^
+// pkg/front_end/testcases/inference/inconsistent_overrides.dart:10:5: Context: This is one of the overridden members.
+//   A f(A x, {A y}) {}
+//     ^
+// pkg/front_end/testcases/inference/inconsistent_overrides.dart:22:5: Context: This is one of the overridden members.
+//   I f(I x, {I y}) {}
+//     ^
+//
+// pkg/front_end/testcases/inference/inconsistent_overrides.dart:17:3: Error: Can't infer types for 'g' as the overridden members don't have a combined signature.
+// Try adding explicit types.
+//   g(x, {y}) {}
+//   ^
+// pkg/front_end/testcases/inference/inconsistent_overrides.dart:11:5: Context: This is one of the overridden members.
+//   A g(A x, {A y}) {}
+//     ^
+// pkg/front_end/testcases/inference/inconsistent_overrides.dart:23:5: Context: This is one of the overridden members.
+//   A g(I x, {I y}) {}
+//     ^
+//
+// pkg/front_end/testcases/inference/inconsistent_overrides.dart:18:3: Error: Can't infer types for 'h' as the overridden members don't have a combined signature.
+// Try adding explicit types.
+//   h(x, {y}) {}
+//   ^
+// pkg/front_end/testcases/inference/inconsistent_overrides.dart:12:5: Context: This is one of the overridden members.
+//   A h(A x, {A y}) {}
+//     ^
+// pkg/front_end/testcases/inference/inconsistent_overrides.dart:24:5: Context: This is one of the overridden members.
+//   A h(A x, {I y}) {}
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method f(self::A* x, {self::A* y = #C1}) → self::A* {}
+  method g(self::A* x, {self::A* y = #C1}) → self::A* {}
+  method h(self::A* x, {self::A* y = #C1}) → self::A* {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A implements self::I {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  method f(invalid-type x, {invalid-type y = #C1}) → invalid-type {}
+  method g(invalid-type x, {invalid-type y = #C1}) → invalid-type {}
+  method h(invalid-type x, {invalid-type y = #C1}) → invalid-type {}
+}
+class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  method f(self::I* x, {self::I* y = #C1}) → self::I* {}
+  method g(self::I* x, {self::I* y = #C1}) → self::A* {}
+  method h(self::A* x, {self::I* y = #C1}) → self::A* {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/inference/index_assign_operator_return_type.dart.weak.modular.expect b/pkg/front_end/testcases/inference/index_assign_operator_return_type.dart.weak.modular.expect
new file mode 100644
index 0000000..d7facc2
--- /dev/null
+++ b/pkg/front_end/testcases/inference/index_assign_operator_return_type.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  operator []=(dynamic index, dynamic value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  operator []=(dynamic index, dynamic value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C implements self::I {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  operator []=(dynamic index, dynamic value) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/index_assign_operator_return_type_2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/index_assign_operator_return_type_2.dart.weak.modular.expect
new file mode 100644
index 0000000..9cecf38
--- /dev/null
+++ b/pkg/front_end/testcases/inference/index_assign_operator_return_type_2.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  operator []=(core::int* index, dynamic value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  operator []=(core::int* index, dynamic value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C implements self::I {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  operator []=(core::int* index, dynamic value) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_accessor_from_later_inferred_field.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_accessor_from_later_inferred_field.dart.weak.modular.expect
new file mode 100644
index 0000000..d6c7c50
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_accessor_from_later_inferred_field.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object implements self::B {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  get x() → core::int*
+    return self::f() as{TypeError,ForDynamic} core::int*;
+  set x(core::int* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  field core::int* x = 0;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f() → dynamic
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_implicit_this.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_implicit_this.dart.weak.modular.expect
new file mode 100644
index 0000000..43a39ef
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_implicit_this.dart.weak.modular.expect
@@ -0,0 +1,72 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class Test extends core::Object {
+  field self::B* member = null;
+  synthetic constructor •() → self::Test*
+    : super core::Object::•()
+    ;
+  method test() → void {
+    this.{self::Test::member} = self::f<self::B*>();
+    this.{self::Test::member}{self::B*} == null ?{self::B*} this.{self::Test::member} = self::f<self::B*>() : null;
+    this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+    this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+    this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+    this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*};
+    this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*};
+    self::B* v1 = this.{self::Test::member} = self::f<self::B*>();
+    self::B* v2 = let final self::B* #t1 = this.{self::Test::member}{self::B*} in #t1 == null ?{self::B*} this.{self::Test::member} = self::f<self::B*>() : #t1;
+    self::A* v3 = this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+    self::B* v4 = this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+    self::C* v5 = this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+    self::B* v6 = this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*};
+    self::B* v7 = let final self::B* #t2 = this.{self::Test::member}{self::B*} in let final self::B* #t3 = this.{self::Test::member} = #t2.{self::B::-}(1){(core::int*) →* self::B*} in #t2;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_implicit_this_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_implicit_this_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..af067f3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_implicit_this_upwards.dart.weak.modular.expect
@@ -0,0 +1,88 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Test1 extends core::Object {
+  field core::int* t = null;
+  synthetic constructor •() → self::Test1*
+    : super core::Object::•()
+    ;
+  method test() → void {
+    core::int* v1 = this.{self::Test1::t} = self::getInt();
+    core::int* v4 = let final core::int* #t1 = this.{self::Test1::t}{core::int*} in #t1 == null ?{core::int*} this.{self::Test1::t} = self::getInt() : #t1;
+    core::int* v7 = this.{self::Test1::t} = this.{self::Test1::t}{core::int*}.{core::num::+}(self::getInt()){(core::num*) →* core::int*};
+    core::int* v10 = this.{self::Test1::t} = this.{self::Test1::t}{core::int*}.{core::num::+}(1){(core::num*) →* core::int*};
+    core::int* v11 = let final core::int* #t2 = this.{self::Test1::t}{core::int*} in let final core::int* #t3 = this.{self::Test1::t} = #t2.{core::num::+}(1){(core::num*) →* core::int*} in #t2;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test2 extends core::Object {
+  field core::num* t = null;
+  synthetic constructor •() → self::Test2*
+    : super core::Object::•()
+    ;
+  method test() → void {
+    core::int* v1 = this.{self::Test2::t} = self::getInt();
+    core::num* v2 = this.{self::Test2::t} = self::getNum();
+    core::double* v3 = this.{self::Test2::t} = self::getDouble();
+    core::num* v4 = let final core::num* #t4 = this.{self::Test2::t}{core::num*} in #t4 == null ?{core::num*} this.{self::Test2::t} = self::getInt() : #t4;
+    core::num* v5 = let final core::num* #t5 = this.{self::Test2::t}{core::num*} in #t5 == null ?{core::num*} this.{self::Test2::t} = self::getNum() : #t5;
+    core::num* v6 = let final core::num* #t6 = this.{self::Test2::t}{core::num*} in #t6 == null ?{core::num*} this.{self::Test2::t} = self::getDouble() : #t6;
+    core::num* v7 = this.{self::Test2::t} = this.{self::Test2::t}{core::num*}.{core::num::+}(self::getInt()){(core::num*) →* core::num*};
+    core::num* v8 = this.{self::Test2::t} = this.{self::Test2::t}{core::num*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*};
+    core::num* v9 = this.{self::Test2::t} = this.{self::Test2::t}{core::num*}.{core::num::+}(self::getDouble()){(core::num*) →* core::num*};
+    core::num* v10 = this.{self::Test2::t} = this.{self::Test2::t}{core::num*}.{core::num::+}(1){(core::num*) →* core::num*};
+    core::num* v11 = let final core::num* #t7 = this.{self::Test2::t}{core::num*} in let final core::num* #t8 = this.{self::Test2::t} = #t7.{core::num::+}(1){(core::num*) →* core::num*} in #t7;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test3 extends core::Object {
+  field core::double* t = null;
+  synthetic constructor •() → self::Test3*
+    : super core::Object::•()
+    ;
+  method test3() → void {
+    core::double* v3 = this.{self::Test3::t} = self::getDouble();
+    core::double* v6 = let final core::double* #t9 = this.{self::Test3::t}{core::double*} in #t9 == null ?{core::double*} this.{self::Test3::t} = self::getDouble() : #t9;
+    core::double* v7 = this.{self::Test3::t} = this.{self::Test3::t}{core::double*}.{core::double::+}(self::getInt()){(core::num*) →* core::double*};
+    core::double* v8 = this.{self::Test3::t} = this.{self::Test3::t}{core::double*}.{core::double::+}(self::getNum()){(core::num*) →* core::double*};
+    core::double* v9 = this.{self::Test3::t} = this.{self::Test3::t}{core::double*}.{core::double::+}(self::getDouble()){(core::num*) →* core::double*};
+    core::double* v10 = this.{self::Test3::t} = this.{self::Test3::t}{core::double*}.{core::double::+}(1){(core::num*) →* core::double*};
+    core::double* v11 = let final core::double* #t10 = this.{self::Test3::t}{core::double*} in let final core::double* #t11 = this.{self::Test3::t} = #t10.{core::double::+}(1){(core::num*) →* core::double*} in #t10;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method getInt() → core::int*
+  return 0;
+static method getNum() → core::num*
+  return 0;
+static method getDouble() → core::double*
+  return 0.0;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_index_full.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_index_full.dart.weak.modular.expect
new file mode 100644
index 0000000..446a6ee
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_index_full.dart.weak.modular.expect
@@ -0,0 +1,91 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Index extends core::Object {
+  synthetic constructor •() → self::Index*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class Test extends core::Object {
+  synthetic constructor •() → self::Test*
+    : super core::Object::•()
+    ;
+  operator [](self::Index* i) → self::B*
+    return null;
+  operator []=(self::Index* i, self::B* v) → void {}
+  method test() → void {
+    self::Test* t = self::f<self::Test*>();
+    t.{self::Test::[]=}(self::f<self::Index*>(), self::f<self::B*>()){(self::Index*, self::B*) →* void};
+    let final self::Test* #t1 = t in let final self::Index* #t2 = self::f<self::Index*>() in #t1.{self::Test::[]}(#t2){(self::Index*) →* self::B*} == null ?{self::B*} #t1.{self::Test::[]=}(#t2, self::f<self::B*>()){(self::Index*, self::B*) →* void} : null;
+    let final self::Test* #t3 = t in let final self::Index* #t4 = self::f<self::Index*>() in #t3.{self::Test::[]=}(#t4, #t3.{self::Test::[]}(#t4){(self::Index*) →* self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*){(self::Index*, self::B*) →* void};
+    let final self::Test* #t5 = t in let final self::Index* #t6 = self::f<self::Index*>() in #t5.{self::Test::[]=}(#t6, #t5.{self::Test::[]}(#t6){(self::Index*) →* self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*}){(self::Index*, self::B*) →* void};
+    let final self::Test* #t7 = t in let final self::Index* #t8 = self::f<self::Index*>() in #t7.{self::Test::[]=}(#t8, #t7.{self::Test::[]}(#t8){(self::Index*) →* self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*}){(self::Index*, self::B*) →* void};
+    t.{self::Test::[]}(self::f<self::Index*>()){(self::Index*) →* self::B*};
+    let final self::Test* #t9 = t in let final self::Index* #t10 = self::f<self::Index*>() in let final self::B* #t11 = #t9.{self::Test::[]}(#t10){(self::Index*) →* self::B*}.{self::B::-}(1){(core::int*) →* self::B*} in let final void #t12 = #t9.{self::Test::[]=}(#t10, #t11){(self::Index*, self::B*) →* void} in #t11;
+    let final self::Test* #t13 = t in let final self::Index* #t14 = self::f<self::Index*>() in #t13.{self::Test::[]=}(#t14, #t13.{self::Test::[]}(#t14){(self::Index*) →* self::B*}.{self::B::-}(1){(core::int*) →* self::B*}){(self::Index*, self::B*) →* void};
+    self::B* v1 = let final self::Test* #t15 = t in let final self::Index* #t16 = self::f<self::Index*>() in let final self::B* #t17 = self::f<self::B*>() in let final void #t18 = #t15.{self::Test::[]=}(#t16, #t17){(self::Index*, self::B*) →* void} in #t17;
+    self::B* v2 = let final self::Test* #t19 = t in let final self::Index* #t20 = self::f<self::Index*>() in let final self::B* #t21 = #t19.{self::Test::[]}(#t20){(self::Index*) →* self::B*} in #t21 == null ?{self::B*} let final self::B* #t22 = self::f<self::B*>() in let final void #t23 = #t19.{self::Test::[]=}(#t20, #t22){(self::Index*, self::B*) →* void} in #t22 : #t21;
+    self::B* v4 = let final self::Test* #t24 = t in let final self::Index* #t25 = self::f<self::Index*>() in let final self::B* #t26 = #t24.{self::Test::[]}(#t25){(self::Index*) →* self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*} in let final void #t27 = #t24.{self::Test::[]=}(#t25, #t26){(self::Index*, self::B*) →* void} in #t26;
+    self::C* v5 = let final self::Test* #t28 = t in let final self::Index* #t29 = self::f<self::Index*>() in let final self::C* #t30 = #t28.{self::Test::[]}(#t29){(self::Index*) →* self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*} in let final void #t31 = #t28.{self::Test::[]=}(#t29, #t30){(self::Index*, self::B*) →* void} in #t30;
+    self::B* v6 = t.{self::Test::[]}(self::f<self::Index*>()){(self::Index*) →* self::B*};
+    self::B* v7 = let final self::Test* #t32 = t in let final self::Index* #t33 = self::f<self::Index*>() in let final self::B* #t34 = #t32.{self::Test::[]}(#t33){(self::Index*) →* self::B*}.{self::B::-}(1){(core::int*) →* self::B*} in let final void #t35 = #t32.{self::Test::[]=}(#t33, #t34){(self::Index*, self::B*) →* void} in #t34;
+    self::B* v8 = let final self::Test* #t36 = t in let final self::Index* #t37 = self::f<self::Index*>() in let final self::B* #t38 = #t36.{self::Test::[]}(#t37){(self::Index*) →* self::B*} in let final void #t39 = #t36.{self::Test::[]=}(#t37, #t38.{self::B::-}(1){(core::int*) →* self::B*}){(self::Index*, self::B*) →* void} in #t38;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_index_super.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_index_super.dart.weak.modular.expect
new file mode 100644
index 0000000..3a7a814
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_index_super.dart.weak.modular.expect
@@ -0,0 +1,94 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Index extends core::Object {
+  synthetic constructor •() → self::Index*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class Base extends core::Object {
+  synthetic constructor •() → self::Base*
+    : super core::Object::•()
+    ;
+  operator [](self::Index* i) → self::B*
+    return null;
+  operator []=(self::Index* i, self::B* v) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test extends self::Base {
+  synthetic constructor •() → self::Test*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    super.{self::Base::[]=}(self::f<self::Index*>(), self::f<self::B*>());
+    let final self::Index* #t1 = self::f<self::Index*>() in super.{self::Base::[]}(#t1) == null ?{self::B*} super.{self::Base::[]=}(#t1, self::f<self::B*>()) : null;
+    let final self::Index* #t2 = self::f<self::Index*>() in super.{self::Base::[]=}(#t2, super.{self::Base::[]}(#t2).{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*);
+    let final self::Index* #t3 = self::f<self::Index*>() in super.{self::Base::[]=}(#t3, super.{self::Base::[]}(#t3).{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*});
+    let final self::Index* #t4 = self::f<self::Index*>() in super.{self::Base::[]=}(#t4, super.{self::Base::[]}(#t4).{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*});
+    let final self::Index* #t5 = self::f<self::Index*>() in let final self::B* #t6 = super.{self::Base::[]}(#t5).{self::B::-}(1){(core::int*) →* self::B*} in let final void #t7 = super.{self::Base::[]=}(#t5, #t6) in #t6;
+    let final self::Index* #t8 = self::f<self::Index*>() in super.{self::Base::[]=}(#t8, super.{self::Base::[]}(#t8).{self::B::-}(1){(core::int*) →* self::B*});
+    self::B* v1 = let final self::Index* #t9 = self::f<self::Index*>() in let final self::B* #t10 = self::f<self::B*>() in let final void #t11 = super.{self::Base::[]=}(#t9, #t10) in #t10;
+    self::B* v2 = let final self::Index* #t12 = self::f<self::Index*>() in let final self::B* #t13 = super.{self::Base::[]}(#t12) in #t13 == null ?{self::B*} let final self::B* #t14 = self::f<self::B*>() in let final void #t15 = super.{self::Base::[]=}(#t12, #t14) in #t14 : #t13;
+    self::A* v3 = let final self::Index* #t16 = self::f<self::Index*>() in let final self::A* #t17 = super.{self::Base::[]}(#t16).{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B* in let final void #t18 = super.{self::Base::[]=}(#t16, #t17) in #t17;
+    self::B* v4 = let final self::Index* #t19 = self::f<self::Index*>() in let final self::B* #t20 = super.{self::Base::[]}(#t19).{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*} in let final void #t21 = super.{self::Base::[]=}(#t19, #t20) in #t20;
+    self::C* v5 = let final self::Index* #t22 = self::f<self::Index*>() in let final self::C* #t23 = super.{self::Base::[]}(#t22).{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*} in let final void #t24 = super.{self::Base::[]=}(#t22, #t23) in #t23;
+    self::B* v6 = let final self::Index* #t25 = self::f<self::Index*>() in let final self::B* #t26 = super.{self::Base::[]}(#t25).{self::B::-}(1){(core::int*) →* self::B*} in let final void #t27 = super.{self::Base::[]=}(#t25, #t26) in #t26;
+    self::B* v7 = let final self::Index* #t28 = self::f<self::Index*>() in let final self::B* #t29 = super.{self::Base::[]}(#t28) in let final void #t30 = super.{self::Base::[]=}(#t28, #t29.{self::B::-}(1){(core::int*) →* self::B*}) in #t29;
+  }
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_index_this.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_index_this.dart.weak.modular.expect
new file mode 100644
index 0000000..d61e224
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_index_this.dart.weak.modular.expect
@@ -0,0 +1,89 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Index extends core::Object {
+  synthetic constructor •() → self::Index*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class Test extends core::Object {
+  synthetic constructor •() → self::Test*
+    : super core::Object::•()
+    ;
+  operator [](self::Index* i) → self::B*
+    return null;
+  operator []=(self::Index* i, self::B* v) → void {}
+  method test() → void {
+    this.{self::Test::[]=}(self::f<self::Index*>(), self::f<self::B*>()){(self::Index*, self::B*) →* void};
+    let final self::Index* #t1 = self::f<self::Index*>() in this.{self::Test::[]}(#t1){(self::Index*) →* self::B*} == null ?{self::B*} this.{self::Test::[]=}(#t1, self::f<self::B*>()){(self::Index*, self::B*) →* void} : null;
+    let final self::Index* #t2 = self::f<self::Index*>() in this.{self::Test::[]=}(#t2, this.{self::Test::[]}(#t2){(self::Index*) →* self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*){(self::Index*, self::B*) →* void};
+    let final self::Index* #t3 = self::f<self::Index*>() in this.{self::Test::[]=}(#t3, this.{self::Test::[]}(#t3){(self::Index*) →* self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*}){(self::Index*, self::B*) →* void};
+    let final self::Index* #t4 = self::f<self::Index*>() in this.{self::Test::[]=}(#t4, this.{self::Test::[]}(#t4){(self::Index*) →* self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*}){(self::Index*, self::B*) →* void};
+    let final self::Index* #t5 = self::f<self::Index*>() in let final self::B* #t6 = this.{self::Test::[]}(#t5){(self::Index*) →* self::B*}.{self::B::-}(1){(core::int*) →* self::B*} in let final void #t7 = this.{self::Test::[]=}(#t5, #t6){(self::Index*, self::B*) →* void} in #t6;
+    let final self::Index* #t8 = self::f<self::Index*>() in this.{self::Test::[]=}(#t8, this.{self::Test::[]}(#t8){(self::Index*) →* self::B*}.{self::B::-}(1){(core::int*) →* self::B*}){(self::Index*, self::B*) →* void};
+    self::B* v1 = let final self::Index* #t9 = self::f<self::Index*>() in let final self::B* #t10 = self::f<self::B*>() in let final void #t11 = this.{self::Test::[]=}(#t9, #t10){(self::Index*, self::B*) →* void} in #t10;
+    self::B* v2 = let final self::Index* #t12 = self::f<self::Index*>() in let final self::B* #t13 = this.{self::Test::[]}(#t12){(self::Index*) →* self::B*} in #t13 == null ?{self::B*} let final self::B* #t14 = self::f<self::B*>() in let final void #t15 = this.{self::Test::[]=}(#t12, #t14){(self::Index*, self::B*) →* void} in #t14 : #t13;
+    self::A* v4 = let final self::Index* #t16 = self::f<self::Index*>() in let final self::A* #t17 = this.{self::Test::[]}(#t16){(self::Index*) →* self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B* in let final void #t18 = this.{self::Test::[]=}(#t16, #t17){(self::Index*, self::B*) →* void} in #t17;
+    self::B* v3 = let final self::Index* #t19 = self::f<self::Index*>() in let final self::B* #t20 = this.{self::Test::[]}(#t19){(self::Index*) →* self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*} in let final void #t21 = this.{self::Test::[]=}(#t19, #t20){(self::Index*, self::B*) →* void} in #t20;
+    self::C* v5 = let final self::Index* #t22 = self::f<self::Index*>() in let final self::C* #t23 = this.{self::Test::[]}(#t22){(self::Index*) →* self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*} in let final void #t24 = this.{self::Test::[]=}(#t22, #t23){(self::Index*, self::B*) →* void} in #t23;
+    self::B* v6 = let final self::Index* #t25 = self::f<self::Index*>() in let final self::B* #t26 = this.{self::Test::[]}(#t25){(self::Index*) →* self::B*}.{self::B::-}(1){(core::int*) →* self::B*} in let final void #t27 = this.{self::Test::[]=}(#t25, #t26){(self::Index*, self::B*) →* void} in #t26;
+    self::B* v7 = let final self::Index* #t28 = self::f<self::Index*>() in let final self::B* #t29 = this.{self::Test::[]}(#t28){(self::Index*) →* self::B*} in let final void #t30 = this.{self::Test::[]=}(#t28, #t29.{self::B::-}(1){(core::int*) →* self::B*}){(self::Index*, self::B*) →* void} in #t29;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_local.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_local.dart.weak.modular.expect
new file mode 100644
index 0000000..5bdc052
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_local.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method test() → void {
+  self::B* local;
+  local = self::f<self::B*>();
+  local == null ?{self::B*} local = self::f<self::B*>() : null;
+  local = local.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+  local = local.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+  local = local.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+  local = local.{self::B::-}(1){(core::int*) →* self::B*};
+  local = local.{self::B::-}(1){(core::int*) →* self::B*};
+  self::B* v1 = local = self::f<self::B*>();
+  self::B* v2 = let final self::B* #t1 = local in #t1 == null ?{self::B*} local = self::f<self::B*>() : #t1;
+  self::A* v3 = local = local.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+  self::B* v4 = local = local.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+  self::C* v5 = local = local.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+  self::B* v6 = local = local.{self::B::-}(1){(core::int*) →* self::B*};
+  self::B* v7 = let final self::B* #t2 = local in let final self::B* #t3 = local = #t2.{self::B::-}(1){(core::int*) →* self::B*} in #t2;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_local_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_local_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..eda9415
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_local_upwards.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method getInt() → core::int*
+  return 0;
+static method getNum() → core::num*
+  return 0;
+static method getDouble() → core::double*
+  return 0.0;
+static method test1(core::int* t) → void {
+  core::int* v1 = t = self::getInt();
+  core::int* v4 = let final core::int* #t1 = t in #t1 == null ?{core::int*} t = self::getInt() : #t1;
+  core::int* v7 = t = t.{core::num::+}(self::getInt()){(core::num*) →* core::int*};
+  core::int* v10 = t = t.{core::num::+}(1){(core::num*) →* core::int*};
+  core::int* v11 = let final core::int* #t2 = t in let final core::int* #t3 = t = #t2.{core::num::+}(1){(core::num*) →* core::int*} in #t2;
+}
+static method test2(core::num* t) → void {
+  core::int* v1 = t = self::getInt();
+  core::num* v2 = t = self::getNum();
+  core::double* v3 = t = self::getDouble();
+  core::num* v4 = let final core::num* #t4 = t in #t4 == null ?{core::num*} t = self::getInt() : #t4;
+  core::num* v5 = let final core::num* #t5 = t in #t5 == null ?{core::num*} t = self::getNum() : #t5;
+  core::num* v6 = let final core::num* #t6 = t in #t6 == null ?{core::num*} t = self::getDouble() : #t6;
+  core::num* v7 = t = t.{core::num::+}(self::getInt()){(core::num*) →* core::num*};
+  core::num* v8 = t = t.{core::num::+}(self::getNum()){(core::num*) →* core::num*};
+  core::num* v9 = t = t.{core::num::+}(self::getDouble()){(core::num*) →* core::num*};
+  core::num* v10 = t = t.{core::num::+}(1){(core::num*) →* core::num*};
+  core::num* v11 = let final core::num* #t7 = t in let final core::num* #t8 = t = #t7.{core::num::+}(1){(core::num*) →* core::num*} in #t7;
+}
+static method test3(core::double* t) → void {
+  core::double* v3 = t = self::getDouble();
+  core::double* v6 = let final core::double* #t9 = t in #t9 == null ?{core::double*} t = self::getDouble() : #t9;
+  core::double* v7 = t = t.{core::double::+}(self::getInt()){(core::num*) →* core::double*};
+  core::double* v8 = t = t.{core::double::+}(self::getNum()){(core::num*) →* core::double*};
+  core::double* v9 = t = t.{core::double::+}(self::getDouble()){(core::num*) →* core::double*};
+  core::double* v10 = t = t.{core::double::+}(1){(core::num*) →* core::double*};
+  core::double* v11 = let final core::double* #t10 = t in let final core::double* #t11 = t = #t10.{core::double::+}(1){(core::num*) →* core::double*} in #t10;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_property_full.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_property_full.dart.weak.modular.expect
new file mode 100644
index 0000000..2e41284
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_property_full.dart.weak.modular.expect
@@ -0,0 +1,72 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class Test extends core::Object {
+  field self::B* member = null;
+  synthetic constructor •() → self::Test*
+    : super core::Object::•()
+    ;
+  static method test(self::Test* t) → void {
+    t.{self::Test::member} = self::f<self::B*>();
+    let final self::Test* #t1 = t in #t1.{self::Test::member}{self::B*} == null ?{self::B*} #t1.{self::Test::member} = self::f<self::B*>() : null;
+    let final self::Test* #t2 = t in #t2.{self::Test::member} = #t2.{self::Test::member}{self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+    let final self::Test* #t3 = t in #t3.{self::Test::member} = #t3.{self::Test::member}{self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+    let final self::Test* #t4 = t in #t4.{self::Test::member} = #t4.{self::Test::member}{self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+    let final self::Test* #t5 = t in #t5.{self::Test::member} = #t5.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*};
+    let final self::Test* #t6 = t in #t6.{self::Test::member} = #t6.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*};
+    self::B* v1 = t.{self::Test::member} = self::f<self::B*>();
+    self::B* v2 = let final self::Test* #t7 = t in let final self::B* #t8 = #t7.{self::Test::member}{self::B*} in #t8 == null ?{self::B*} #t7.{self::Test::member} = self::f<self::B*>() : #t8;
+    self::A* v3 = let final self::Test* #t9 = t in #t9.{self::Test::member} = #t9.{self::Test::member}{self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+    self::B* v4 = let final self::Test* #t10 = t in #t10.{self::Test::member} = #t10.{self::Test::member}{self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+    self::C* v5 = let final self::Test* #t11 = t in #t11.{self::Test::member} = #t11.{self::Test::member}{self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+    self::B* v6 = let final self::Test* #t12 = t in #t12.{self::Test::member} = #t12.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*};
+    self::B* v7 = let final self::Test* #t13 = t in let final self::B* #t14 = #t13.{self::Test::member}{self::B*} in let final self::B* #t15 = #t13.{self::Test::member} = #t14.{self::B::-}(1){(core::int*) →* self::B*} in #t14;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_property_null_aware.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_property_null_aware.dart.weak.modular.expect
new file mode 100644
index 0000000..681f9aa
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_property_null_aware.dart.weak.modular.expect
@@ -0,0 +1,72 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class Test extends core::Object {
+  field self::B* member = null;
+  synthetic constructor •() → self::Test*
+    : super core::Object::•()
+    ;
+  static method test(self::Test* t) → void {
+    let final self::Test* #t1 = t in #t1 == null ?{self::B*} null : #t1.{self::Test::member} = self::f<self::B*>();
+    let final self::Test* #t2 = t in #t2 == null ?{self::B*} null : #t2.{self::Test::member}{self::B*} == null ?{self::B*} #t2.{self::Test::member} = self::f<self::B*>() : null;
+    let final self::Test* #t3 = t in #t3 == null ?{self::A*} null : #t3.{self::Test::member} = #t3.{self::Test::member}{self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+    let final self::Test* #t4 = t in #t4 == null ?{self::B*} null : #t4.{self::Test::member} = #t4.{self::Test::member}{self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+    let final self::Test* #t5 = t in #t5 == null ?{self::C*} null : #t5.{self::Test::member} = #t5.{self::Test::member}{self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+    let final self::Test* #t6 = t in #t6 == null ?{self::B*} null : let final self::B* #t7 = #t6.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*} in let final void #t8 = #t6.{self::Test::member} = #t7 in #t7;
+    let final self::Test* #t9 = t in #t9 == null ?{self::B*} null : #t9.{self::Test::member} = #t9.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*};
+    self::B* v1 = let final self::Test* #t10 = t in #t10 == null ?{self::B*} null : #t10.{self::Test::member} = self::f<self::B*>();
+    self::B* v2 = let final self::Test* #t11 = t in #t11 == null ?{self::B*} null : let final self::B* #t12 = #t11.{self::Test::member}{self::B*} in #t12 == null ?{self::B*} #t11.{self::Test::member} = self::f<self::B*>() : #t12;
+    self::A* v3 = let final self::Test* #t13 = t in #t13 == null ?{self::A*} null : let final self::A* #t14 = #t13.{self::Test::member}{self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B* in let final void #t15 = #t13.{self::Test::member} = #t14 in #t14;
+    self::B* v4 = let final self::Test* #t16 = t in #t16 == null ?{self::B*} null : let final self::B* #t17 = #t16.{self::Test::member}{self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*} in let final void #t18 = #t16.{self::Test::member} = #t17 in #t17;
+    self::C* v5 = let final self::Test* #t19 = t in #t19 == null ?{self::C*} null : let final self::C* #t20 = #t19.{self::Test::member}{self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*} in let final void #t21 = #t19.{self::Test::member} = #t20 in #t20;
+    self::B* v6 = let final self::Test* #t22 = t in #t22 == null ?{self::B*} null : let final self::B* #t23 = #t22.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*} in let final void #t24 = #t22.{self::Test::member} = #t23 in #t23;
+    self::B* v7 = let final self::Test* #t25 = t in #t25 == null ?{self::B*} null : let final self::B* #t26 = #t25.{self::Test::member}{self::B*} in let final void #t27 = #t25.{self::Test::member} = #t26.{self::B::-}(1){(core::int*) →* self::B*} in #t26;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_property_null_aware_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_property_null_aware_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..defcb5a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_property_null_aware_upwards.dart.weak.modular.expect
@@ -0,0 +1,88 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Test1 extends core::Object {
+  field core::int* prop = null;
+  synthetic constructor •() → self::Test1*
+    : super core::Object::•()
+    ;
+  static method test(self::Test1* t) → void {
+    core::int* v1 = let final self::Test1* #t1 = t in #t1 == null ?{core::int*} null : #t1.{self::Test1::prop} = self::getInt();
+    core::int* v4 = let final self::Test1* #t2 = t in #t2 == null ?{core::int*} null : let final core::int* #t3 = #t2.{self::Test1::prop}{core::int*} in #t3 == null ?{core::int*} #t2.{self::Test1::prop} = self::getInt() : #t3;
+    core::int* v7 = let final self::Test1* #t4 = t in #t4 == null ?{core::int*} null : let final core::int* #t5 = #t4.{self::Test1::prop}{core::int*}.{core::num::+}(self::getInt()){(core::num*) →* core::int*} in let final void #t6 = #t4.{self::Test1::prop} = #t5 in #t5;
+    core::int* v10 = let final self::Test1* #t7 = t in #t7 == null ?{core::int*} null : let final core::int* #t8 = #t7.{self::Test1::prop}{core::int*}.{core::num::+}(1){(core::num*) →* core::int*} in let final void #t9 = #t7.{self::Test1::prop} = #t8 in #t8;
+    core::int* v11 = let final self::Test1* #t10 = t in #t10 == null ?{core::int*} null : let final core::int* #t11 = #t10.{self::Test1::prop}{core::int*} in let final void #t12 = #t10.{self::Test1::prop} = #t11.{core::num::+}(1){(core::num*) →* core::int*} in #t11;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test2 extends core::Object {
+  field core::num* prop = null;
+  synthetic constructor •() → self::Test2*
+    : super core::Object::•()
+    ;
+  static method test(self::Test2* t) → void {
+    core::int* v1 = let final self::Test2* #t13 = t in #t13 == null ?{core::int*} null : #t13.{self::Test2::prop} = self::getInt();
+    core::num* v2 = let final self::Test2* #t14 = t in #t14 == null ?{core::num*} null : #t14.{self::Test2::prop} = self::getNum();
+    core::double* v3 = let final self::Test2* #t15 = t in #t15 == null ?{core::double*} null : #t15.{self::Test2::prop} = self::getDouble();
+    core::num* v4 = let final self::Test2* #t16 = t in #t16 == null ?{core::num*} null : let final core::num* #t17 = #t16.{self::Test2::prop}{core::num*} in #t17 == null ?{core::num*} #t16.{self::Test2::prop} = self::getInt() : #t17;
+    core::num* v5 = let final self::Test2* #t18 = t in #t18 == null ?{core::num*} null : let final core::num* #t19 = #t18.{self::Test2::prop}{core::num*} in #t19 == null ?{core::num*} #t18.{self::Test2::prop} = self::getNum() : #t19;
+    core::num* v6 = let final self::Test2* #t20 = t in #t20 == null ?{core::num*} null : let final core::num* #t21 = #t20.{self::Test2::prop}{core::num*} in #t21 == null ?{core::num*} #t20.{self::Test2::prop} = self::getDouble() : #t21;
+    core::num* v7 = let final self::Test2* #t22 = t in #t22 == null ?{core::num*} null : let final core::num* #t23 = #t22.{self::Test2::prop}{core::num*}.{core::num::+}(self::getInt()){(core::num*) →* core::num*} in let final void #t24 = #t22.{self::Test2::prop} = #t23 in #t23;
+    core::num* v8 = let final self::Test2* #t25 = t in #t25 == null ?{core::num*} null : let final core::num* #t26 = #t25.{self::Test2::prop}{core::num*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} in let final void #t27 = #t25.{self::Test2::prop} = #t26 in #t26;
+    core::num* v9 = let final self::Test2* #t28 = t in #t28 == null ?{core::num*} null : let final core::num* #t29 = #t28.{self::Test2::prop}{core::num*}.{core::num::+}(self::getDouble()){(core::num*) →* core::num*} in let final void #t30 = #t28.{self::Test2::prop} = #t29 in #t29;
+    core::num* v10 = let final self::Test2* #t31 = t in #t31 == null ?{core::num*} null : let final core::num* #t32 = #t31.{self::Test2::prop}{core::num*}.{core::num::+}(1){(core::num*) →* core::num*} in let final void #t33 = #t31.{self::Test2::prop} = #t32 in #t32;
+    core::num* v11 = let final self::Test2* #t34 = t in #t34 == null ?{core::num*} null : let final core::num* #t35 = #t34.{self::Test2::prop}{core::num*} in let final void #t36 = #t34.{self::Test2::prop} = #t35.{core::num::+}(1){(core::num*) →* core::num*} in #t35;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test3 extends core::Object {
+  field core::double* prop = null;
+  synthetic constructor •() → self::Test3*
+    : super core::Object::•()
+    ;
+  static method test3(self::Test3* t) → void {
+    core::double* v3 = let final self::Test3* #t37 = t in #t37 == null ?{core::double*} null : #t37.{self::Test3::prop} = self::getDouble();
+    core::double* v6 = let final self::Test3* #t38 = t in #t38 == null ?{core::double*} null : let final core::double* #t39 = #t38.{self::Test3::prop}{core::double*} in #t39 == null ?{core::double*} #t38.{self::Test3::prop} = self::getDouble() : #t39;
+    core::double* v7 = let final self::Test3* #t40 = t in #t40 == null ?{core::double*} null : let final core::double* #t41 = #t40.{self::Test3::prop}{core::double*}.{core::double::+}(self::getInt()){(core::num*) →* core::double*} in let final void #t42 = #t40.{self::Test3::prop} = #t41 in #t41;
+    core::double* v8 = let final self::Test3* #t43 = t in #t43 == null ?{core::double*} null : let final core::double* #t44 = #t43.{self::Test3::prop}{core::double*}.{core::double::+}(self::getNum()){(core::num*) →* core::double*} in let final void #t45 = #t43.{self::Test3::prop} = #t44 in #t44;
+    core::double* v9 = let final self::Test3* #t46 = t in #t46 == null ?{core::double*} null : let final core::double* #t47 = #t46.{self::Test3::prop}{core::double*}.{core::double::+}(self::getDouble()){(core::num*) →* core::double*} in let final void #t48 = #t46.{self::Test3::prop} = #t47 in #t47;
+    core::double* v10 = let final self::Test3* #t49 = t in #t49 == null ?{core::double*} null : let final core::double* #t50 = #t49.{self::Test3::prop}{core::double*}.{core::double::+}(1){(core::num*) →* core::double*} in let final void #t51 = #t49.{self::Test3::prop} = #t50 in #t50;
+    core::double* v11 = let final self::Test3* #t52 = t in #t52 == null ?{core::double*} null : let final core::double* #t53 = #t52.{self::Test3::prop}{core::double*} in let final void #t54 = #t52.{self::Test3::prop} = #t53.{core::double::+}(1){(core::num*) →* core::double*} in #t53;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method getInt() → core::int*
+  return 0;
+static method getNum() → core::num*
+  return 0;
+static method getDouble() → core::double*
+  return 0.0;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_property_super.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_property_super.dart.weak.modular.expect
new file mode 100644
index 0000000..28b3433
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_property_super.dart.weak.modular.expect
@@ -0,0 +1,77 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class Base extends core::Object {
+  field self::B* member = null;
+  synthetic constructor •() → self::Base*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test extends self::Base {
+  synthetic constructor •() → self::Test*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    super.{self::Base::member} = self::f<self::B*>();
+    super.{self::Base::member} == null ?{self::B*} super.{self::Base::member} = self::f<self::B*>() : null;
+    super.{self::Base::member} = super.{self::Base::member}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+    super.{self::Base::member} = super.{self::Base::member}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+    super.{self::Base::member} = super.{self::Base::member}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+    super.{self::Base::member} = super.{self::Base::member}.{self::B::-}(1){(core::int*) →* self::B*};
+    super.{self::Base::member} = super.{self::Base::member}.{self::B::-}(1){(core::int*) →* self::B*};
+    self::B* v1 = super.{self::Base::member} = self::f<self::B*>();
+    self::B* v2 = let final self::B* #t1 = super.{self::Base::member} in #t1 == null ?{self::B*} super.{self::Base::member} = self::f<self::B*>() : #t1;
+    self::A* v3 = super.{self::Base::member} = super.{self::Base::member}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+    self::B* v4 = super.{self::Base::member} = super.{self::Base::member}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+    self::C* v5 = super.{self::Base::member} = super.{self::Base::member}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+    self::B* v6 = super.{self::Base::member} = super.{self::Base::member}.{self::B::-}(1){(core::int*) →* self::B*};
+    self::B* v7 = let final self::B* #t2 = super.{self::Base::member} in let final self::B* #t3 = super.{self::Base::member} = #t2.{self::B::-}(1){(core::int*) →* self::B*} in #t2;
+  }
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_property_super_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_property_super_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..15883a8
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_property_super_upwards.dart.weak.modular.expect
@@ -0,0 +1,73 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Base extends core::Object {
+  field core::int* intProp = null;
+  field core::num* numProp = null;
+  field core::double* doubleProp = null;
+  synthetic constructor •() → self::Base*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test1 extends self::Base {
+  synthetic constructor •() → self::Test1*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    core::int* v1 = super.{self::Base::intProp} = self::getInt();
+    core::int* v4 = let final core::int* #t1 = super.{self::Base::intProp} in #t1 == null ?{core::int*} super.{self::Base::intProp} = self::getInt() : #t1;
+    core::int* v7 = super.{self::Base::intProp} = super.{self::Base::intProp}.{core::num::+}(self::getInt()){(core::num*) →* core::int*};
+    core::int* v10 = super.{self::Base::intProp} = super.{self::Base::intProp}.{core::num::+}(1){(core::num*) →* core::int*};
+    core::int* v11 = let final core::int* #t2 = super.{self::Base::intProp} in let final core::int* #t3 = super.{self::Base::intProp} = #t2.{core::num::+}(1){(core::num*) →* core::int*} in #t2;
+  }
+}
+class Test2 extends self::Base {
+  synthetic constructor •() → self::Test2*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    core::int* v1 = super.{self::Base::numProp} = self::getInt();
+    core::num* v2 = super.{self::Base::numProp} = self::getNum();
+    core::double* v3 = super.{self::Base::numProp} = self::getDouble();
+    core::num* v4 = let final core::num* #t4 = super.{self::Base::numProp} in #t4 == null ?{core::num*} super.{self::Base::numProp} = self::getInt() : #t4;
+    core::num* v5 = let final core::num* #t5 = super.{self::Base::numProp} in #t5 == null ?{core::num*} super.{self::Base::numProp} = self::getNum() : #t5;
+    core::num* v6 = let final core::num* #t6 = super.{self::Base::numProp} in #t6 == null ?{core::num*} super.{self::Base::numProp} = self::getDouble() : #t6;
+    core::num* v7 = super.{self::Base::numProp} = super.{self::Base::numProp}.{core::num::+}(self::getInt()){(core::num*) →* core::num*};
+    core::num* v8 = super.{self::Base::numProp} = super.{self::Base::numProp}.{core::num::+}(self::getNum()){(core::num*) →* core::num*};
+    core::num* v9 = super.{self::Base::numProp} = super.{self::Base::numProp}.{core::num::+}(self::getDouble()){(core::num*) →* core::num*};
+    core::num* v10 = super.{self::Base::numProp} = super.{self::Base::numProp}.{core::num::+}(1){(core::num*) →* core::num*};
+    core::num* v11 = let final core::num* #t7 = super.{self::Base::numProp} in let final core::num* #t8 = super.{self::Base::numProp} = #t7.{core::num::+}(1){(core::num*) →* core::num*} in #t7;
+  }
+}
+class Test3 extends self::Base {
+  synthetic constructor •() → self::Test3*
+    : super self::Base::•()
+    ;
+  method test3() → void {
+    core::double* v3 = super.{self::Base::doubleProp} = self::getDouble();
+    core::double* v6 = let final core::double* #t9 = super.{self::Base::doubleProp} in #t9 == null ?{core::double*} super.{self::Base::doubleProp} = self::getDouble() : #t9;
+    core::double* v7 = super.{self::Base::doubleProp} = super.{self::Base::doubleProp}.{core::double::+}(self::getInt()){(core::num*) →* core::double*};
+    core::double* v8 = super.{self::Base::doubleProp} = super.{self::Base::doubleProp}.{core::double::+}(self::getNum()){(core::num*) →* core::double*};
+    core::double* v9 = super.{self::Base::doubleProp} = super.{self::Base::doubleProp}.{core::double::+}(self::getDouble()){(core::num*) →* core::double*};
+    core::double* v10 = super.{self::Base::doubleProp} = super.{self::Base::doubleProp}.{core::double::+}(1){(core::num*) →* core::double*};
+    core::double* v11 = let final core::double* #t10 = super.{self::Base::doubleProp} in let final core::double* #t11 = super.{self::Base::doubleProp} = #t10.{core::double::+}(1){(core::num*) →* core::double*} in #t10;
+  }
+}
+static method getInt() → core::int*
+  return 0;
+static method getNum() → core::num*
+  return 0;
+static method getDouble() → core::double*
+  return 0.0;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_property_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_property_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..1e03234
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_property_upwards.dart.weak.modular.expect
@@ -0,0 +1,88 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Test1 extends core::Object {
+  field core::int* prop = null;
+  synthetic constructor •() → self::Test1*
+    : super core::Object::•()
+    ;
+  static method test(self::Test1* t) → void {
+    core::int* v1 = t.{self::Test1::prop} = self::getInt();
+    core::int* v4 = let final self::Test1* #t1 = t in let final core::int* #t2 = #t1.{self::Test1::prop}{core::int*} in #t2 == null ?{core::int*} #t1.{self::Test1::prop} = self::getInt() : #t2;
+    core::int* v7 = let final self::Test1* #t3 = t in #t3.{self::Test1::prop} = #t3.{self::Test1::prop}{core::int*}.{core::num::+}(self::getInt()){(core::num*) →* core::int*};
+    core::int* v10 = let final self::Test1* #t4 = t in #t4.{self::Test1::prop} = #t4.{self::Test1::prop}{core::int*}.{core::num::+}(1){(core::num*) →* core::int*};
+    core::int* v11 = let final self::Test1* #t5 = t in let final core::int* #t6 = #t5.{self::Test1::prop}{core::int*} in let final core::int* #t7 = #t5.{self::Test1::prop} = #t6.{core::num::+}(1){(core::num*) →* core::int*} in #t6;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test2 extends core::Object {
+  field core::num* prop = null;
+  synthetic constructor •() → self::Test2*
+    : super core::Object::•()
+    ;
+  static method test(self::Test2* t) → void {
+    core::int* v1 = t.{self::Test2::prop} = self::getInt();
+    core::num* v2 = t.{self::Test2::prop} = self::getNum();
+    core::double* v3 = t.{self::Test2::prop} = self::getDouble();
+    core::num* v4 = let final self::Test2* #t8 = t in let final core::num* #t9 = #t8.{self::Test2::prop}{core::num*} in #t9 == null ?{core::num*} #t8.{self::Test2::prop} = self::getInt() : #t9;
+    core::num* v5 = let final self::Test2* #t10 = t in let final core::num* #t11 = #t10.{self::Test2::prop}{core::num*} in #t11 == null ?{core::num*} #t10.{self::Test2::prop} = self::getNum() : #t11;
+    core::num* v6 = let final self::Test2* #t12 = t in let final core::num* #t13 = #t12.{self::Test2::prop}{core::num*} in #t13 == null ?{core::num*} #t12.{self::Test2::prop} = self::getDouble() : #t13;
+    core::num* v7 = let final self::Test2* #t14 = t in #t14.{self::Test2::prop} = #t14.{self::Test2::prop}{core::num*}.{core::num::+}(self::getInt()){(core::num*) →* core::num*};
+    core::num* v8 = let final self::Test2* #t15 = t in #t15.{self::Test2::prop} = #t15.{self::Test2::prop}{core::num*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*};
+    core::num* v9 = let final self::Test2* #t16 = t in #t16.{self::Test2::prop} = #t16.{self::Test2::prop}{core::num*}.{core::num::+}(self::getDouble()){(core::num*) →* core::num*};
+    core::num* v10 = let final self::Test2* #t17 = t in #t17.{self::Test2::prop} = #t17.{self::Test2::prop}{core::num*}.{core::num::+}(1){(core::num*) →* core::num*};
+    core::num* v11 = let final self::Test2* #t18 = t in let final core::num* #t19 = #t18.{self::Test2::prop}{core::num*} in let final core::num* #t20 = #t18.{self::Test2::prop} = #t19.{core::num::+}(1){(core::num*) →* core::num*} in #t19;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test3 extends core::Object {
+  field core::double* prop = null;
+  synthetic constructor •() → self::Test3*
+    : super core::Object::•()
+    ;
+  static method test3(self::Test3* t) → void {
+    core::double* v3 = t.{self::Test3::prop} = self::getDouble();
+    core::double* v6 = let final self::Test3* #t21 = t in let final core::double* #t22 = #t21.{self::Test3::prop}{core::double*} in #t22 == null ?{core::double*} #t21.{self::Test3::prop} = self::getDouble() : #t22;
+    core::double* v7 = let final self::Test3* #t23 = t in #t23.{self::Test3::prop} = #t23.{self::Test3::prop}{core::double*}.{core::double::+}(self::getInt()){(core::num*) →* core::double*};
+    core::double* v8 = let final self::Test3* #t24 = t in #t24.{self::Test3::prop} = #t24.{self::Test3::prop}{core::double*}.{core::double::+}(self::getNum()){(core::num*) →* core::double*};
+    core::double* v9 = let final self::Test3* #t25 = t in #t25.{self::Test3::prop} = #t25.{self::Test3::prop}{core::double*}.{core::double::+}(self::getDouble()){(core::num*) →* core::double*};
+    core::double* v10 = let final self::Test3* #t26 = t in #t26.{self::Test3::prop} = #t26.{self::Test3::prop}{core::double*}.{core::double::+}(1){(core::num*) →* core::double*};
+    core::double* v11 = let final self::Test3* #t27 = t in let final core::double* #t28 = #t27.{self::Test3::prop}{core::double*} in let final core::double* #t29 = #t27.{self::Test3::prop} = #t28.{core::double::+}(1){(core::num*) →* core::double*} in #t28;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method getInt() → core::int*
+  return 0;
+static method getNum() → core::num*
+  return 0;
+static method getDouble() → core::double*
+  return 0.0;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_ref.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_ref.dart.weak.modular.expect
new file mode 100644
index 0000000..e1508e3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_ref.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* f = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::A* a = new self::A::•();
+static field core::int* c = 0;
+static method main() → dynamic {
+  self::a;
+  self::c;
+}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_static.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_static.dart.weak.modular.expect
new file mode 100644
index 0000000..090413f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_static.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  static field self::B* staticVariable = null;
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+static field self::B* topLevelVariable;
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method test_topLevelVariable() → void {
+  self::topLevelVariable = self::f<self::B*>();
+  self::topLevelVariable == null ?{self::B*} self::topLevelVariable = self::f<self::B*>() : null;
+  self::topLevelVariable = self::topLevelVariable.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+  self::topLevelVariable = self::topLevelVariable.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+  self::topLevelVariable = self::topLevelVariable.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+  self::topLevelVariable = self::topLevelVariable.{self::B::-}(1){(core::int*) →* self::B*};
+  self::topLevelVariable = self::topLevelVariable.{self::B::-}(1){(core::int*) →* self::B*};
+  self::B* v1 = self::topLevelVariable = self::f<self::B*>();
+  self::B* v2 = let final self::B* #t1 = self::topLevelVariable in #t1 == null ?{self::B*} self::topLevelVariable = self::f<self::B*>() : #t1;
+  self::A* v3 = self::topLevelVariable = self::topLevelVariable.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+  self::B* v4 = self::topLevelVariable = self::topLevelVariable.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+  self::C* v5 = self::topLevelVariable = self::topLevelVariable.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+  self::B* v6 = self::topLevelVariable = self::topLevelVariable.{self::B::-}(1){(core::int*) →* self::B*};
+  self::B* v7 = let final self::B* #t2 = self::topLevelVariable in let final self::B* #t3 = self::topLevelVariable = #t2.{self::B::-}(1){(core::int*) →* self::B*} in #t2;
+}
+static method test_staticVariable() → void {
+  self::B::staticVariable = self::f<self::B*>();
+  self::B::staticVariable == null ?{self::B*} self::B::staticVariable = self::f<self::B*>() : null;
+  self::B::staticVariable = self::B::staticVariable.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+  self::B::staticVariable = self::B::staticVariable.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+  self::B::staticVariable = self::B::staticVariable.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+  self::B::staticVariable = self::B::staticVariable.{self::B::-}(1){(core::int*) →* self::B*};
+  self::B::staticVariable = self::B::staticVariable.{self::B::-}(1){(core::int*) →* self::B*};
+  self::B* v1 = self::B::staticVariable = self::f<self::B*>();
+  self::B* v2 = let final self::B* #t4 = self::B::staticVariable in #t4 == null ?{self::B*} self::B::staticVariable = self::f<self::B*>() : #t4;
+  self::A* v3 = self::B::staticVariable = self::B::staticVariable.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+  self::B* v4 = self::B::staticVariable = self::B::staticVariable.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+  self::C* v5 = self::B::staticVariable = self::B::staticVariable.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+  self::B* v6 = self::B::staticVariable = self::B::staticVariable.{self::B::-}(1){(core::int*) →* self::B*};
+  self::B* v7 = let final self::B* #t5 = self::B::staticVariable in let final self::B* #t6 = self::B::staticVariable = #t5.{self::B::-}(1){(core::int*) →* self::B*} in #t5;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_assign_to_static_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_assign_to_static_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..4130e63
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_assign_to_static_upwards.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::int* topLevelInt;
+static field core::num* topLevelNum;
+static field core::double* topLevelDouble;
+static method getInt() → core::int*
+  return 0;
+static method getNum() → core::num*
+  return 0;
+static method getDouble() → core::double*
+  return 0.0;
+static method test1() → void {
+  core::int* v1 = self::topLevelInt = self::getInt();
+  core::int* v4 = let final core::int* #t1 = self::topLevelInt in #t1 == null ?{core::int*} self::topLevelInt = self::getInt() : #t1;
+  core::int* v7 = self::topLevelInt = self::topLevelInt.{core::num::+}(self::getInt()){(core::num*) →* core::int*};
+  core::int* v10 = self::topLevelInt = self::topLevelInt.{core::num::+}(1){(core::num*) →* core::int*};
+  core::int* v11 = let final core::int* #t2 = self::topLevelInt in let final core::int* #t3 = self::topLevelInt = #t2.{core::num::+}(1){(core::num*) →* core::int*} in #t2;
+}
+static method test2() → void {
+  core::int* v1 = self::topLevelNum = self::getInt();
+  core::num* v2 = self::topLevelNum = self::getNum();
+  core::double* v3 = self::topLevelNum = self::getDouble();
+  core::num* v4 = let final core::num* #t4 = self::topLevelNum in #t4 == null ?{core::num*} self::topLevelNum = self::getInt() : #t4;
+  core::num* v5 = let final core::num* #t5 = self::topLevelNum in #t5 == null ?{core::num*} self::topLevelNum = self::getNum() : #t5;
+  core::num* v6 = let final core::num* #t6 = self::topLevelNum in #t6 == null ?{core::num*} self::topLevelNum = self::getDouble() : #t6;
+  core::num* v7 = self::topLevelNum = self::topLevelNum.{core::num::+}(self::getInt()){(core::num*) →* core::num*};
+  core::num* v8 = self::topLevelNum = self::topLevelNum.{core::num::+}(self::getNum()){(core::num*) →* core::num*};
+  core::num* v9 = self::topLevelNum = self::topLevelNum.{core::num::+}(self::getDouble()){(core::num*) →* core::num*};
+  core::num* v10 = self::topLevelNum = self::topLevelNum.{core::num::+}(1){(core::num*) →* core::num*};
+  core::num* v11 = let final core::num* #t7 = self::topLevelNum in let final core::num* #t8 = self::topLevelNum = #t7.{core::num::+}(1){(core::num*) →* core::num*} in #t7;
+}
+static method test3() → void {
+  core::double* v3 = self::topLevelDouble = self::getDouble();
+  core::double* v6 = let final core::double* #t9 = self::topLevelDouble in #t9 == null ?{core::double*} self::topLevelDouble = self::getDouble() : #t9;
+  core::double* v7 = self::topLevelDouble = self::topLevelDouble.{core::double::+}(self::getInt()){(core::num*) →* core::double*};
+  core::double* v8 = self::topLevelDouble = self::topLevelDouble.{core::double::+}(self::getNum()){(core::num*) →* core::double*};
+  core::double* v9 = self::topLevelDouble = self::topLevelDouble.{core::double::+}(self::getDouble()){(core::num*) →* core::double*};
+  core::double* v10 = self::topLevelDouble = self::topLevelDouble.{core::double::+}(1){(core::num*) →* core::double*};
+  core::double* v11 = let final core::double* #t10 = self::topLevelDouble in let final core::double* #t11 = self::topLevelDouble = #t10.{core::double::+}(1){(core::num*) →* core::double*} in #t10;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_binary_custom.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_binary_custom.dart.weak.modular.expect
new file mode 100644
index 0000000..2fd7b9e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_binary_custom.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator +(dynamic other) → core::int*
+    return 1;
+  operator -(dynamic other) → core::double*
+    return 2.0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* v_add = new self::A::•().{self::A::+}("foo"){(dynamic) →* core::int*};
+static field core::double* v_minus = new self::A::•().{self::A::-}("bar"){(dynamic) →* core::double*};
+static method main() → dynamic {
+  self::v_add;
+  self::v_minus;
+}
diff --git a/pkg/front_end/testcases/inference/infer_binary_double_double.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_binary_double_double.dart.weak.modular.expect
new file mode 100644
index 0000000..38be484
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_binary_double_double.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::bool* a_equal = 1.0 =={core::num::==}{(core::Object*) →* core::bool*} 2.0;
+static field core::bool* a_notEqual = !(1.0 =={core::num::==}{(core::Object*) →* core::bool*} 2.0);
+static field core::double* a_add = 1.0.{core::double::+}(2.0){(core::num*) →* core::double*};
+static field core::double* a_subtract = 1.0.{core::double::-}(2.0){(core::num*) →* core::double*};
+static field core::double* a_multiply = 1.0.{core::double::*}(2.0){(core::num*) →* core::double*};
+static field core::double* a_divide = 1.0.{core::double::/}(2.0){(core::num*) →* core::double*};
+static field core::int* a_floorDivide = 1.0.{core::double::~/}(2.0){(core::num*) →* core::int*};
+static field core::bool* a_greater = 1.0.{core::num::>}(2.0){(core::num*) →* core::bool*};
+static field core::bool* a_less = 1.0.{core::num::<}(2.0){(core::num*) →* core::bool*};
+static field core::bool* a_greaterEqual = 1.0.{core::num::>=}(2.0){(core::num*) →* core::bool*};
+static field core::bool* a_lessEqual = 1.0.{core::num::<=}(2.0){(core::num*) →* core::bool*};
+static field core::double* a_modulo = 1.0.{core::double::%}(2.0){(core::num*) →* core::double*};
+static method main() → dynamic {
+  self::a_equal;
+  self::a_notEqual;
+  self::a_add;
+  self::a_subtract;
+  self::a_multiply;
+  self::a_divide;
+  self::a_floorDivide;
+  self::a_greater;
+  self::a_less;
+  self::a_greaterEqual;
+  self::a_lessEqual;
+  self::a_modulo;
+}
diff --git a/pkg/front_end/testcases/inference/infer_binary_double_int.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_binary_double_int.dart.weak.modular.expect
new file mode 100644
index 0000000..1f62c1e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_binary_double_int.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::bool* a_equal = 1.0 =={core::num::==}{(core::Object*) →* core::bool*} 2;
+static field core::bool* a_notEqual = !(1.0 =={core::num::==}{(core::Object*) →* core::bool*} 2);
+static field core::double* a_add = 1.0.{core::double::+}(2){(core::num*) →* core::double*};
+static field core::double* a_subtract = 1.0.{core::double::-}(2){(core::num*) →* core::double*};
+static field core::double* a_multiply = 1.0.{core::double::*}(2){(core::num*) →* core::double*};
+static field core::double* a_divide = 1.0.{core::double::/}(2){(core::num*) →* core::double*};
+static field core::int* a_floorDivide = 1.0.{core::double::~/}(2){(core::num*) →* core::int*};
+static field core::bool* a_greater = 1.0.{core::num::>}(2){(core::num*) →* core::bool*};
+static field core::bool* a_less = 1.0.{core::num::<}(2){(core::num*) →* core::bool*};
+static field core::bool* a_greaterEqual = 1.0.{core::num::>=}(2){(core::num*) →* core::bool*};
+static field core::bool* a_lessEqual = 1.0.{core::num::<=}(2){(core::num*) →* core::bool*};
+static field core::double* a_modulo = 1.0.{core::double::%}(2){(core::num*) →* core::double*};
+static method main() → dynamic {
+  self::a_equal;
+  self::a_notEqual;
+  self::a_add;
+  self::a_subtract;
+  self::a_multiply;
+  self::a_divide;
+  self::a_floorDivide;
+  self::a_greater;
+  self::a_less;
+  self::a_greaterEqual;
+  self::a_lessEqual;
+  self::a_modulo;
+}
diff --git a/pkg/front_end/testcases/inference/infer_binary_int_double.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_binary_int_double.dart.weak.modular.expect
new file mode 100644
index 0000000..1e26a3e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_binary_int_double.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::bool* a_equal = 1 =={core::num::==}{(core::Object*) →* core::bool*} 2.0;
+static field core::bool* a_notEqual = !(1 =={core::num::==}{(core::Object*) →* core::bool*} 2.0);
+static field core::double* a_add = 1.{core::num::+}(2.0){(core::num*) →* core::double*};
+static field core::double* a_subtract = 1.{core::num::-}(2.0){(core::num*) →* core::double*};
+static field core::double* a_multiply = 1.{core::num::*}(2.0){(core::num*) →* core::double*};
+static field core::double* a_divide = 1.{core::num::/}(2.0){(core::num*) →* core::double*};
+static field core::int* a_floorDivide = 1.{core::num::~/}(2.0){(core::num*) →* core::int*};
+static field core::bool* a_greater = 1.{core::num::>}(2.0){(core::num*) →* core::bool*};
+static field core::bool* a_less = 1.{core::num::<}(2.0){(core::num*) →* core::bool*};
+static field core::bool* a_greaterEqual = 1.{core::num::>=}(2.0){(core::num*) →* core::bool*};
+static field core::bool* a_lessEqual = 1.{core::num::<=}(2.0){(core::num*) →* core::bool*};
+static field core::double* a_modulo = 1.{core::num::%}(2.0){(core::num*) →* core::double*};
+static method main() → dynamic {
+  self::a_equal;
+  self::a_notEqual;
+  self::a_add;
+  self::a_subtract;
+  self::a_multiply;
+  self::a_divide;
+  self::a_floorDivide;
+  self::a_greater;
+  self::a_less;
+  self::a_greaterEqual;
+  self::a_lessEqual;
+  self::a_modulo;
+}
diff --git a/pkg/front_end/testcases/inference/infer_binary_int_int.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_binary_int_int.dart.weak.modular.expect
new file mode 100644
index 0000000..883662f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_binary_int_int.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::bool* a_equal = 1 =={core::num::==}{(core::Object*) →* core::bool*} 2;
+static field core::bool* a_notEqual = !(1 =={core::num::==}{(core::Object*) →* core::bool*} 2);
+static field core::int* a_bitXor = 1.{core::int::^}(2){(core::int*) →* core::int*};
+static field core::int* a_bitAnd = 1.{core::int::&}(2){(core::int*) →* core::int*};
+static field core::int* a_bitOr = 1.{core::int::|}(2){(core::int*) →* core::int*};
+static field core::int* a_bitShiftRight = 1.{core::int::>>}(2){(core::int*) →* core::int*};
+static field core::int* a_bitShiftLeft = 1.{core::int::<<}(2){(core::int*) →* core::int*};
+static field core::int* a_add = 1.{core::num::+}(2){(core::num*) →* core::int*};
+static field core::int* a_subtract = 1.{core::num::-}(2){(core::num*) →* core::int*};
+static field core::int* a_multiply = 1.{core::num::*}(2){(core::num*) →* core::int*};
+static field core::double* a_divide = 1.{core::num::/}(2){(core::num*) →* core::double*};
+static field core::int* a_floorDivide = 1.{core::num::~/}(2){(core::num*) →* core::int*};
+static field core::bool* a_greater = 1.{core::num::>}(2){(core::num*) →* core::bool*};
+static field core::bool* a_less = 1.{core::num::<}(2){(core::num*) →* core::bool*};
+static field core::bool* a_greaterEqual = 1.{core::num::>=}(2){(core::num*) →* core::bool*};
+static field core::bool* a_lessEqual = 1.{core::num::<=}(2){(core::num*) →* core::bool*};
+static field core::int* a_modulo = 1.{core::num::%}(2){(core::num*) →* core::int*};
+static method main() → dynamic {
+  self::a_equal;
+  self::a_notEqual;
+  self::a_bitXor;
+  self::a_bitAnd;
+  self::a_bitOr;
+  self::a_bitShiftRight;
+  self::a_bitShiftLeft;
+  self::a_add;
+  self::a_subtract;
+  self::a_multiply;
+  self::a_divide;
+  self::a_floorDivide;
+  self::a_greater;
+  self::a_less;
+  self::a_greaterEqual;
+  self::a_lessEqual;
+  self::a_modulo;
+}
diff --git a/pkg/front_end/testcases/inference/infer_conditional.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_conditional.dart.weak.modular.expect
new file mode 100644
index 0000000..b2128b8
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_conditional.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::num* a = 1 =={core::num::==}{(core::Object*) →* core::bool*} 2 ?{core::num*} 1 : 2.0;
+static field core::num* b = 1 =={core::num::==}{(core::Object*) →* core::bool*} 2 ?{core::num*} 1.0 : 2;
+static method main() → dynamic {
+  self::a;
+  self::b;
+}
diff --git a/pkg/front_end/testcases/inference/infer_consts_transitively_2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_consts_transitively_2.dart.weak.modular.expect
new file mode 100644
index 0000000..ba94200
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_consts_transitively_2.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///infer_consts_transitively_2_a.dart";
+
+static const field core::int* m1 = #C1;
+static const field core::int* m2 = #C1;
+static method foo() → dynamic {
+  core::int* i;
+  i = #C1;
+}
+static method main() → dynamic {}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///infer_consts_transitively_2.dart";
+import "org-dartlang-testcase:///infer_consts_transitively_2_b.dart";
+
+static const field core::int* a1 = #C1;
+static const field core::int* a2 = #C1;
+static method main() → dynamic {}
+
+library;
+import self as self3;
+import "dart:core" as core;
+
+static const field core::int* b1 = #C1;
+static method main() → dynamic {
+  #C1;
+}
+
+constants  {
+  #C1 = 2
+}
diff --git a/pkg/front_end/testcases/inference/infer_consts_transitively_2_a.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_consts_transitively_2_a.dart.weak.modular.expect
new file mode 100644
index 0000000..7f72a48
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_consts_transitively_2_a.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///infer_consts_transitively_2.dart";
+import "org-dartlang-testcase:///infer_consts_transitively_2_b.dart";
+
+static const field core::int* a1 = #C1;
+static const field core::int* a2 = #C1;
+static method main() → dynamic {}
+
+library test;
+import self as self2;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///infer_consts_transitively_2_a.dart";
+
+static const field core::int* m1 = #C1;
+static const field core::int* m2 = #C1;
+static method foo() → dynamic {
+  core::int* i;
+  i = #C1;
+}
+static method main() → dynamic {}
+
+library;
+import self as self3;
+import "dart:core" as core;
+
+static const field core::int* b1 = #C1;
+static method main() → dynamic {
+  #C1;
+}
+
+constants  {
+  #C1 = 2
+}
diff --git a/pkg/front_end/testcases/inference/infer_consts_transitively_2_b.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_consts_transitively_2_b.dart.weak.modular.expect
new file mode 100644
index 0000000..85d3066
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_consts_transitively_2_b.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static const field core::int* b1 = #C1;
+static method main() → dynamic {
+  #C1;
+}
+
+constants  {
+  #C1 = 2
+}
diff --git a/pkg/front_end/testcases/inference/infer_consts_transitively_b.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_consts_transitively_b.dart.weak.modular.expect
new file mode 100644
index 0000000..85d3066
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_consts_transitively_b.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static const field core::int* b1 = #C1;
+static method main() → dynamic {
+  #C1;
+}
+
+constants  {
+  #C1 = 2
+}
diff --git a/pkg/front_end/testcases/inference/infer_correctly_on_multiple_variables_declared_together.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_correctly_on_multiple_variables_declared_together.dart.weak.modular.expect
new file mode 100644
index 0000000..5692085
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_correctly_on_multiple_variables_declared_together.dart.weak.modular.expect
@@ -0,0 +1,75 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_correctly_on_multiple_variables_declared_together.dart:21:61: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   s = /*error:INVALID_ASSIGNMENT*/ new B(). /*@target=B.y*/ y;
+//                                                             ^
+//
+// pkg/front_end/testcases/inference/infer_correctly_on_multiple_variables_declared_together.dart:23:61: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   s = /*error:INVALID_ASSIGNMENT*/ new B(). /*@target=B.w*/ w;
+//                                                             ^
+//
+// pkg/front_end/testcases/inference/infer_correctly_on_multiple_variables_declared_together.dart:27:61: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   i = /*error:INVALID_ASSIGNMENT*/ new B(). /*@target=B.z*/ z;
+//                                                             ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field dynamic x = null;
+  field core::int* y = 2;
+  field core::String* z = "hi";
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::A {
+  field dynamic x = 2;
+  field core::int* y = 3;
+  field core::String* z = null;
+  field core::int* w = 2;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo() → dynamic {
+  core::String* s;
+  core::int* i;
+  s = new self::B::•().{self::B::x}{dynamic} as{TypeError,ForDynamic} core::String*;
+  s = invalid-expression "pkg/front_end/testcases/inference/infer_correctly_on_multiple_variables_declared_together.dart:21:61: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  s = /*error:INVALID_ASSIGNMENT*/ new B(). /*@target=B.y*/ y;
+                                                            ^" in new self::B::•().{self::B::y}{core::int*} as{TypeError} core::String*;
+  s = new self::B::•().{self::B::z}{core::String*};
+  s = invalid-expression "pkg/front_end/testcases/inference/infer_correctly_on_multiple_variables_declared_together.dart:23:61: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  s = /*error:INVALID_ASSIGNMENT*/ new B(). /*@target=B.w*/ w;
+                                                            ^" in new self::B::•().{self::B::w}{core::int*} as{TypeError} core::String*;
+  i = new self::B::•().{self::B::x}{dynamic} as{TypeError,ForDynamic} core::int*;
+  i = new self::B::•().{self::B::y}{core::int*};
+  i = invalid-expression "pkg/front_end/testcases/inference/infer_correctly_on_multiple_variables_declared_together.dart:27:61: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  i = /*error:INVALID_ASSIGNMENT*/ new B(). /*@target=B.z*/ z;
+                                                            ^" in new self::B::•().{self::B::z}{core::String*} as{TypeError} core::int*;
+  i = new self::B::•().{self::B::w}{core::int*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_field_from_later_inferred_field.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_field_from_later_inferred_field.dart.weak.modular.expect
new file mode 100644
index 0000000..ba522a3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_field_from_later_inferred_field.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object implements self::B {
+  field core::int* x = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  field core::int* x = 0;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_field_from_later_inferred_getter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_field_from_later_inferred_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..cc037d5
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_field_from_later_inferred_getter.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object implements self::B {
+  field core::int* x = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object implements self::C {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_field_from_later_inferred_setter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_field_from_later_inferred_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..ad938ca
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_field_from_later_inferred_setter.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object implements self::B {
+  field core::int* x = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object implements self::C {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract set x(core::int* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract set x(core::int* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_field_override_multiple.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_field_override_multiple.dart.weak.modular.expect
new file mode 100644
index 0000000..4c56b7e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_field_override_multiple.dart.weak.modular.expect
@@ -0,0 +1,107 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_field_override_multiple.dart:36:7: Error: Can't infer a type for 'x' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var x;
+//       ^
+// pkg/front_end/testcases/inference/infer_field_override_multiple.dart:9:11: Context: This is one of the overridden members.
+//   int get x;
+//           ^
+// pkg/front_end/testcases/inference/infer_field_override_multiple.dart:21:14: Context: This is one of the overridden members.
+//   double get x;
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::num*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D extends core::Object {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::double*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E extends self::A implements self::B {
+  field core::int* x = null;
+  synthetic constructor •() → self::E*
+    : super self::A::•()
+    ;
+}
+class F extends self::A implements self::C {
+  field core::int* x = null;
+  synthetic constructor •() → self::F*
+    : super self::A::•()
+    ;
+}
+class G extends self::A implements self::D {
+  field invalid-type x = null;
+  synthetic constructor •() → self::G*
+    : super self::A::•()
+    ;
+}
+class H extends self::C implements self::D {
+  field core::double* x = null;
+  synthetic constructor •() → self::H*
+    : super self::C::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_field_override_of_override.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_field_override_of_override.dart.weak.modular.expect
new file mode 100644
index 0000000..c1a5df1
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_field_override_of_override.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::num*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  abstract get x() → core::int*;
+}
+class C extends self::B {
+  field core::int* x = null;
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_field_override_with_substitution.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_field_override_with_substitution.dart.weak.modular.expect
new file mode 100644
index 0000000..7b26ea1
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_field_override_with_substitution.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class A<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field core::List<self::A::T*>* z = null;
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::List<self::A::T*>*;
+  abstract set y(covariant-by-class core::List<self::A::T*>* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A<core::int*> {
+  field core::List<core::int*>* x = null;
+  covariant-by-class field core::List<core::int*>* y = null;
+  covariant-by-class field core::List<core::int*>* z = null;
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_field_overrides_getter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_field_overrides_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..c7c2a14
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_field_overrides_getter.dart.weak.modular.expect
@@ -0,0 +1,105 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  get x() → core::int*
+    return 0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::A {
+  field core::int* x = null;
+  synthetic constructor •() → self::C*
+    : super self::A::•()
+    ;
+}
+class D extends self::B {
+  field core::int* x = null;
+  synthetic constructor •() → self::D*
+    : super self::B::•()
+    ;
+}
+class E extends core::Object implements self::A {
+  field core::int* x = null;
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F extends core::Object implements self::B {
+  field core::int* x = null;
+  synthetic constructor •() → self::F*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _G&Object&B = core::Object with self::B /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_G&Object&B*
+    : super core::Object::•()
+    ;
+  mixin-super-stub get x() → core::int*
+    return super.{self::B::x};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class G extends self::_G&Object&B {
+  field core::int* x = null;
+  synthetic constructor •() → self::G*
+    : super self::_G&Object&B::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_field_overrides_setter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_field_overrides_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..476388a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_field_overrides_setter.dart.weak.modular.expect
@@ -0,0 +1,104 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract set x(core::int* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  set x(core::int* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::A {
+  field core::int* x = null;
+  synthetic constructor •() → self::C*
+    : super self::A::•()
+    ;
+}
+class D extends self::B {
+  field core::int* x = null;
+  synthetic constructor •() → self::D*
+    : super self::B::•()
+    ;
+}
+class E extends core::Object implements self::A {
+  field core::int* x = null;
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F extends core::Object implements self::B {
+  field core::int* x = null;
+  synthetic constructor •() → self::F*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _G&Object&B = core::Object with self::B /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_G&Object&B*
+    : super core::Object::•()
+    ;
+  mixin-super-stub set x(core::int* value) → void
+    return super.{self::B::x} = value;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class G extends self::_G&Object&B {
+  field core::int* x = null;
+  synthetic constructor •() → self::G*
+    : super self::_G&Object&B::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_field_static.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_field_static.dart.weak.modular.expect
new file mode 100644
index 0000000..c785e64
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_field_static.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  static get x() → core::int*
+    return 0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  static field dynamic x = self::f();
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C extends self::A {
+  static field dynamic x = null;
+  synthetic constructor •() → self::C*
+    : super self::A::•()
+    ;
+}
+static method f() → dynamic
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_final_field_getter_and_setter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_final_field_getter_and_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..3eab43e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_final_field_getter_and_setter.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_final_field_getter_and_setter.dart:9:11: Error: The type 'int' of the getter 'A.x' is not assignable to the type 'double' of the setter 'A.x'.
+//   int get x;
+//           ^
+// pkg/front_end/testcases/inference/infer_final_field_getter_and_setter.dart:10:12: Context: This is the declaration of the setter 'A.x'.
+//   void set x(double value) {}
+//            ^
+//
+// pkg/front_end/testcases/inference/infer_final_field_getter_and_setter.dart:14:9: Error: The type 'int' of the field 'B.x' is not assignable to the type 'double' of the inherited setter 'A.x'.
+//   final x;
+//         ^
+// pkg/front_end/testcases/inference/infer_final_field_getter_and_setter.dart:10:12: Context: This is the declaration of the setter 'A.x'.
+//   void set x(double value) {}
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::int*;
+  set x(core::double* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  final field core::int* x;
+  constructor •(core::int* x) → self::B*
+    : self::B::x = x, super self::A::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_final_field_getter_only.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_final_field_getter_only.dart.weak.modular.expect
new file mode 100644
index 0000000..2668951
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_final_field_getter_only.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  final field core::int* x;
+  constructor •(core::int* x) → self::B*
+    : self::B::x = x, super self::A::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_final_field_setter_only.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_final_field_setter_only.dart.weak.modular.expect
new file mode 100644
index 0000000..287066b
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_final_field_setter_only.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  set x(core::double* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  final field core::double* x;
+  constructor •(core::double* x) → self::B*
+    : self::B::x = x, super self::A::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart.weak.modular.expect
new file mode 100644
index 0000000..a18d682
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart.weak.modular.expect
@@ -0,0 +1,191 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:19:46: Error: Undefined name 'x'.
+// var b = new B(/*error:UNDEFINED_IDENTIFIER*/ x); // allocations
+//                                              ^
+//
+// pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:21:34: Error: Undefined name 'x'.
+//   /*error:UNDEFINED_IDENTIFIER*/ x
+//                                  ^
+//
+// pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:32:58: Error: The operator 'unary-' isn't defined for the class 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart'.
+// Try correcting the operator to an existing operator, or defining a 'unary-' operator.
+// var i = /*error:UNDEFINED_OPERATOR,info:DYNAMIC_INVOKE*/ -new A();
+//                                                          ^
+//
+// pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:36:36: Error: A value of type 'String' can't be assigned to a variable of type 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart'.
+//   a = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                    ^
+//
+// pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:38:36: Error: A value of type 'String' can't be assigned to a variable of type 'B'.
+//  - 'B' is from 'pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart'.
+//   b = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                    ^
+//
+// pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:41:59: Error: A value of type 'Set<dynamic>' can't be assigned to a variable of type 'List<invalid-type>'.
+//  - 'Set' is from 'dart:core'.
+//  - 'List' is from 'dart:core'.
+//   c1 = /*error:INVALID_ASSIGNMENT*/ /*@typeArgs=dynamic*/ {};
+//                                                           ^
+//
+// pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:43:59: Error: A value of type 'Set<dynamic>' can't be assigned to a variable of type 'List<dynamic>'.
+//  - 'Set' is from 'dart:core'.
+//  - 'List' is from 'dart:core'.
+//   c2 = /*error:INVALID_ASSIGNMENT*/ /*@typeArgs=dynamic*/ {};
+//                                                           ^
+//
+// pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:45:36: Error: A value of type 'int' can't be assigned to a variable of type 'Map<dynamic, dynamic>'.
+//  - 'Map' is from 'dart:core'.
+//   d = /*error:INVALID_ASSIGNMENT*/ 3;
+//                                    ^
+//
+// pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:47:67: Error: A value of type 'Map<dynamic, dynamic>' can't be assigned to a variable of type 'A'.
+//  - 'Map' is from 'dart:core'.
+//  - 'A' is from 'pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart'.
+//   e = /*error:INVALID_ASSIGNMENT*/ /*@typeArgs=dynamic, dynamic*/ {};
+//                                                                   ^
+//
+// pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:49:36: Error: A value of type 'bool' can't be assigned to a variable of type 'int'.
+//   f = /*error:INVALID_ASSIGNMENT*/ false;
+//                                    ^
+//
+// pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:51:36: Error: A value of type 'bool' can't be assigned to a variable of type 'int'.
+//   g = /*error:INVALID_ASSIGNMENT*/ false;
+//                                    ^
+//
+// pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:52:36: Error: A value of type 'bool' can't be assigned to a variable of type 'B'.
+//  - 'B' is from 'pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart'.
+//   h = /*error:INVALID_ASSIGNMENT*/ false;
+//                                    ^
+//
+// pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:56:36: Error: A value of type 'bool' can't be assigned to a variable of type 'B'.
+//  - 'B' is from 'pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart'.
+//   j = /*error:INVALID_ASSIGNMENT*/ false;
+//                                    ^
+//
+// pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:57:58: Error: A value of type 'List<dynamic>' can't be assigned to a variable of type 'B'.
+//  - 'List' is from 'dart:core'.
+//  - 'B' is from 'pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart'.
+//   j = /*error:INVALID_ASSIGNMENT*/ /*@typeArgs=dynamic*/ [];
+//                                                          ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+class A extends core::Object {
+  field core::int* x = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator +(dynamic other) → self::B*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  constructor •(dynamic ignore) → self::B*
+    : super self::A::•()
+    ;
+}
+static field self::A* a = new self::A::•();
+static field self::B* b = new self::B::•(invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:19:46: Error: Undefined name 'x'.
+var b = new B(/*error:UNDEFINED_IDENTIFIER*/ x); // allocations
+                                             ^");
+static field core::List<invalid-type>* c1 = <invalid-type>[invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:21:34: Error: Undefined name 'x'.
+  /*error:UNDEFINED_IDENTIFIER*/ x
+                                 ^"];
+static field core::List<dynamic>* c2 = #C1;
+static field core::Map<dynamic, dynamic>* d = <dynamic, dynamic>{"a": "b"};
+static field self::A* e = let final self::A* #t1 = new self::A::•() in block {
+  #t1.{self::A::x} = 3;
+} =>#t1;
+static field core::int* f = 2.{core::num::+}(3){(core::num*) →* core::int*};
+static field core::int* g = 3.{core::int::unary-}(){() →* core::int*};
+static field self::B* h = new self::A::•().{self::A::+}(3){(dynamic) →* self::B*};
+static field dynamic i = invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:32:58: Error: The operator 'unary-' isn't defined for the class 'A'.
+ - 'A' is from 'pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart'.
+Try correcting the operator to an existing operator, or defining a 'unary-' operator.
+var i = /*error:UNDEFINED_OPERATOR,info:DYNAMIC_INVOKE*/ -new A();
+                                                         ^" in new self::A::•(){<unresolved>}.unary-();
+static field self::B* j = null as self::B*;
+static method test1() → dynamic {
+  self::a = invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:36:36: Error: A value of type 'String' can't be assigned to a variable of type 'A'.
+ - 'A' is from 'pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart'.
+  a = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                   ^" in "hi" as{TypeError} self::A*;
+  self::a = new self::B::•(3);
+  self::b = invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:38:36: Error: A value of type 'String' can't be assigned to a variable of type 'B'.
+ - 'B' is from 'pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart'.
+  b = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                   ^" in "hi" as{TypeError} self::B*;
+  self::b = new self::B::•(3);
+  self::c1 = <invalid-type>[];
+  self::c1 = invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:41:59: Error: A value of type 'Set<dynamic>' can't be assigned to a variable of type 'List<invalid-type>'.
+ - 'Set' is from 'dart:core'.
+ - 'List' is from 'dart:core'.
+  c1 = /*error:INVALID_ASSIGNMENT*/ /*@typeArgs=dynamic*/ {};
+                                                          ^" in ( block {
+    final core::Set<dynamic>* #t2 = col::LinkedHashSet::•<dynamic>();
+  } =>#t2) as{TypeError} core::List<invalid-type>*;
+  self::c2 = <dynamic>[];
+  self::c2 = invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:43:59: Error: A value of type 'Set<dynamic>' can't be assigned to a variable of type 'List<dynamic>'.
+ - 'Set' is from 'dart:core'.
+ - 'List' is from 'dart:core'.
+  c2 = /*error:INVALID_ASSIGNMENT*/ /*@typeArgs=dynamic*/ {};
+                                                          ^" in ( block {
+    final core::Set<dynamic>* #t3 = col::LinkedHashSet::•<dynamic>();
+  } =>#t3) as{TypeError} core::List<dynamic>*;
+  self::d = <dynamic, dynamic>{};
+  self::d = invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:45:36: Error: A value of type 'int' can't be assigned to a variable of type 'Map<dynamic, dynamic>'.
+ - 'Map' is from 'dart:core'.
+  d = /*error:INVALID_ASSIGNMENT*/ 3;
+                                   ^" in 3 as{TypeError} core::Map<dynamic, dynamic>*;
+  self::e = new self::A::•();
+  self::e = invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:47:67: Error: A value of type 'Map<dynamic, dynamic>' can't be assigned to a variable of type 'A'.
+ - 'Map' is from 'dart:core'.
+ - 'A' is from 'pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart'.
+  e = /*error:INVALID_ASSIGNMENT*/ /*@typeArgs=dynamic, dynamic*/ {};
+                                                                  ^" in <dynamic, dynamic>{} as{TypeError} self::A*;
+  self::f = 3;
+  self::f = invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:49:36: Error: A value of type 'bool' can't be assigned to a variable of type 'int'.
+  f = /*error:INVALID_ASSIGNMENT*/ false;
+                                   ^" in false as{TypeError} core::int*;
+  self::g = 1;
+  self::g = invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:51:36: Error: A value of type 'bool' can't be assigned to a variable of type 'int'.
+  g = /*error:INVALID_ASSIGNMENT*/ false;
+                                   ^" in false as{TypeError} core::int*;
+  self::h = invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:52:36: Error: A value of type 'bool' can't be assigned to a variable of type 'B'.
+ - 'B' is from 'pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart'.
+  h = /*error:INVALID_ASSIGNMENT*/ false;
+                                   ^" in false as{TypeError} self::B*;
+  self::h = new self::B::•("b");
+  self::i = false;
+  self::j = new self::B::•("b");
+  self::j = invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:56:36: Error: A value of type 'bool' can't be assigned to a variable of type 'B'.
+ - 'B' is from 'pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart'.
+  j = /*error:INVALID_ASSIGNMENT*/ false;
+                                   ^" in false as{TypeError} self::B*;
+  self::j = invalid-expression "pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart:57:58: Error: A value of type 'List<dynamic>' can't be assigned to a variable of type 'B'.
+ - 'List' is from 'dart:core'.
+ - 'B' is from 'pkg/front_end/testcases/inference/infer_from_complex_expressions_if_outer_most_value_is_precise.dart'.
+  j = /*error:INVALID_ASSIGNMENT*/ /*@typeArgs=dynamic*/ [];
+                                                         ^" in <dynamic>[] as{TypeError} self::B*;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = <dynamic>[]
+}
diff --git a/pkg/front_end/testcases/inference/infer_from_rhs_only_if_it_wont_conflict_with_overridden_fields.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_from_rhs_only_if_it_wont_conflict_with_overridden_fields.dart.weak.modular.expect
new file mode 100644
index 0000000..8b4fa52
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_from_rhs_only_if_it_wont_conflict_with_overridden_fields.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field dynamic x = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::A {
+  field dynamic x = 2;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo() → dynamic {
+  core::String* y = new self::B::•().{self::B::x}{dynamic} as{TypeError,ForDynamic} core::String*;
+  core::int* z = new self::B::•().{self::B::x}{dynamic} as{TypeError,ForDynamic} core::int*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_from_rhs_only_if_it_wont_conflict_with_overridden_fields2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_from_rhs_only_if_it_wont_conflict_with_overridden_fields2.dart.weak.modular.expect
new file mode 100644
index 0000000..d5127a5
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_from_rhs_only_if_it_wont_conflict_with_overridden_fields2.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  final field dynamic x = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::A {
+  final field dynamic x = 2;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo() → dynamic {
+  core::String* y = new self::B::•().{self::B::x}{dynamic} as{TypeError,ForDynamic} core::String*;
+  core::int* z = new self::B::•().{self::B::x}{dynamic} as{TypeError,ForDynamic} core::int*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_from_variables_in_cycle_libs_when_flag_is_on.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_from_variables_in_cycle_libs_when_flag_is_on.dart.weak.modular.expect
new file mode 100644
index 0000000..79f52e7
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_from_variables_in_cycle_libs_when_flag_is_on.dart.weak.modular.expect
@@ -0,0 +1,77 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "infer_from_variables_in_cycle_libs_when_flag_is_on_a.dart" as inf;
+
+import "org-dartlang-testcase:///infer_from_variables_in_cycle_libs_when_flag_is_on_a.dart";
+
+static field core::int* y = inf::x;
+static method test1() → dynamic {
+  core::int* t = 3;
+  t = inf::x;
+  t = self::y;
+}
+static method main() → dynamic {}
+
+library;
+import self as inf;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///infer_from_variables_in_cycle_libs_when_flag_is_on2.dart";
+
+static field core::int* x = 2;
+static method main() → dynamic {}
+
+library test;
+import self as self2;
+import "dart:core" as core;
+import "infer_from_variables_in_cycle_libs_when_flag_is_on2_a.dart" as inf2;
+
+import "org-dartlang-testcase:///infer_from_variables_in_cycle_libs_when_flag_is_on2_a.dart";
+
+class B extends core::Object {
+  static field core::int* y = inf2::A::x;
+  synthetic constructor •() → self2::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test1() → dynamic {
+  core::int* t = 3;
+  t = inf2::A::x;
+  t = self2::B::y;
+}
+static method main() → dynamic {}
+
+library;
+import self as inf2;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///infer_from_variables_in_cycle_libs_when_flag_is_on2.dart";
+
+class A extends core::Object {
+  static field core::int* x = 2;
+  synthetic constructor •() → inf2::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_from_variables_in_cycle_libs_when_flag_is_on2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_from_variables_in_cycle_libs_when_flag_is_on2.dart.weak.modular.expect
new file mode 100644
index 0000000..fb74297
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_from_variables_in_cycle_libs_when_flag_is_on2.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "infer_from_variables_in_cycle_libs_when_flag_is_on2_a.dart" as inf;
+
+import "org-dartlang-testcase:///infer_from_variables_in_cycle_libs_when_flag_is_on2_a.dart";
+
+class B extends core::Object {
+  static field core::int* y = inf::A::x;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test1() → dynamic {
+  core::int* t = 3;
+  t = inf::A::x;
+  t = self::B::y;
+}
+static method main() → dynamic {}
+
+library;
+import self as inf;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///infer_from_variables_in_cycle_libs_when_flag_is_on2.dart";
+
+class A extends core::Object {
+  static field core::int* x = 2;
+  synthetic constructor •() → inf::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_from_variables_in_cycle_libs_when_flag_is_on2_a.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_from_variables_in_cycle_libs_when_flag_is_on2_a.dart.weak.modular.expect
new file mode 100644
index 0000000..da8a870
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_from_variables_in_cycle_libs_when_flag_is_on2_a.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///infer_from_variables_in_cycle_libs_when_flag_is_on2.dart";
+
+class A extends core::Object {
+  static field core::int* x = 2;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+library test;
+import self as self2;
+import "dart:core" as core;
+import "infer_from_variables_in_cycle_libs_when_flag_is_on2_a.dart" as self;
+
+import "org-dartlang-testcase:///infer_from_variables_in_cycle_libs_when_flag_is_on2_a.dart";
+
+class B extends core::Object {
+  static field core::int* y = self::A::x;
+  synthetic constructor •() → self2::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test1() → dynamic {
+  core::int* t = 3;
+  t = self::A::x;
+  t = self2::B::y;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_from_variables_in_cycle_libs_when_flag_is_on_a.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_from_variables_in_cycle_libs_when_flag_is_on_a.dart.weak.modular.expect
new file mode 100644
index 0000000..7e9fca5
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_from_variables_in_cycle_libs_when_flag_is_on_a.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///infer_from_variables_in_cycle_libs_when_flag_is_on2.dart";
+
+static field core::int* x = 2;
+static method main() → dynamic {}
+
+library test;
+import self as self2;
+import "dart:core" as core;
+import "infer_from_variables_in_cycle_libs_when_flag_is_on2_a.dart" as inf;
+
+import "org-dartlang-testcase:///infer_from_variables_in_cycle_libs_when_flag_is_on2_a.dart";
+
+class B extends core::Object {
+  static field core::int* y = inf::A::x;
+  synthetic constructor •() → self2::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test1() → dynamic {
+  core::int* t = 3;
+  t = inf::A::x;
+  t = self2::B::y;
+}
+static method main() → dynamic {}
+
+library;
+import self as inf;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///infer_from_variables_in_cycle_libs_when_flag_is_on2.dart";
+
+class A extends core::Object {
+  static field core::int* x = 2;
+  synthetic constructor •() → inf::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag.dart.weak.modular.expect
new file mode 100644
index 0000000..cfb8761
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag.dart:13:36: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   x = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                    ^
+//
+// pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag.dart:14:36: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   y = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                    ^
+//
+import self as self;
+import "infer_from_variables_in_non_cycle_imports_with_flag_a.dart" as inf;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///infer_from_variables_in_non_cycle_imports_with_flag_a.dart";
+
+static field core::int* y = inf::x;
+static method test1() → dynamic {
+  inf::x = invalid-expression "pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag.dart:13:36: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  x = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                   ^" in "hi" as{TypeError} core::int*;
+  self::y = invalid-expression "pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag.dart:14:36: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  y = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                   ^" in "hi" as{TypeError} core::int*;
+}
+static method main() → dynamic {}
+
+library;
+import self as inf;
+import "dart:core" as core;
+
+static field core::int* x = 2;
+static method main() → dynamic {
+  inf::x;
+}
diff --git a/pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag2.dart.weak.modular.expect
new file mode 100644
index 0000000..74f640c
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag2.dart.weak.modular.expect
@@ -0,0 +1,65 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag2.dart:15:38: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   A.x = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                      ^
+//
+// pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag2.dart:16:38: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   B.y = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                      ^
+//
+import self as self;
+import "dart:core" as core;
+import "infer_from_variables_in_non_cycle_imports_with_flag2_a.dart" as inf;
+
+import "org-dartlang-testcase:///infer_from_variables_in_non_cycle_imports_with_flag2_a.dart";
+
+class B extends core::Object {
+  static field core::int* y = inf::A::x;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test1() → dynamic {
+  inf::A::x = invalid-expression "pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag2.dart:15:38: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  A.x = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                     ^" in "hi" as{TypeError} core::int*;
+  self::B::y = invalid-expression "pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag2.dart:16:38: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  B.y = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                     ^" in "hi" as{TypeError} core::int*;
+}
+static method main() → dynamic {}
+
+library;
+import self as inf;
+import "dart:core" as core;
+
+class A extends core::Object {
+  static field core::int* x = 2;
+  synthetic constructor •() → inf::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag2_a.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag2_a.dart.weak.modular.expect
new file mode 100644
index 0000000..81376fe
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag2_a.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  static field core::int* x = 2;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag_a.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag_a.dart.weak.modular.expect
new file mode 100644
index 0000000..298b12b
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_from_variables_in_non_cycle_imports_with_flag_a.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static field core::int* x = 2;
+static method main() → dynamic {
+  self::x;
+}
diff --git a/pkg/front_end/testcases/inference/infer_generic_field_types.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_generic_field_types.dart.weak.modular.expect
new file mode 100644
index 0000000..91d941e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_generic_field_types.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::A::X* field = null;
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B<Y extends core::Object* = dynamic> extends core::Object implements self::A<self::B::Y*> {
+  synthetic constructor •() → self::B<self::B::Y*>*
+    : super core::Object::•()
+    ;
+  abstract get field() → self::B::Y*;
+  abstract set field(covariant-by-class self::B::Y* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object implements self::A<core::int*> {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract get field() → core::int*;
+  abstract set field(covariant-by-class core::int* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_generic_method_type_named.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_generic_method_type_named.dart.weak.modular.expect
new file mode 100644
index 0000000..6d31625
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_generic_method_type_named.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method m<T extends core::Object* = dynamic>(core::int* a, {core::String* b = #C1, self::C::m::T* c = #C1}) → self::C::m::T*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::double* y = new self::C::•().{self::C::m}<core::double*>(1, b: "bbb", c: 2.0){(core::int*, {b: core::String*, c: core::double*}) →* core::double*};
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/inference/infer_generic_method_type_positional.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_generic_method_type_positional.dart.weak.modular.expect
new file mode 100644
index 0000000..5c86982
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_generic_method_type_positional.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method m<T extends core::Object* = dynamic>(core::int* a, [self::C::m::T* b = #C1]) → self::C::m::T*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::double* y = new self::C::•().{self::C::m}<core::double*>(1, 2.0){(core::int*, [core::double*]) →* core::double*};
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/inference/infer_generic_method_type_positional2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_generic_method_type_positional2.dart.weak.modular.expect
new file mode 100644
index 0000000..7af5aa7
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_generic_method_type_positional2.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method m<T extends core::Object* = dynamic>(core::int* a, [core::String* b = #C1, self::C::m::T* c = #C1]) → self::C::m::T*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::double* y = new self::C::•().{self::C::m}<core::double*>(1, "bbb", 2.0){(core::int*, [core::String*, core::double*]) →* core::double*};
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/inference/infer_generic_method_type_required.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_generic_method_type_required.dart.weak.modular.expect
new file mode 100644
index 0000000..4435be3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_generic_method_type_required.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method m<T extends core::Object* = dynamic>(self::C::m::T* x) → self::C::m::T*
+    return x;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::int* y = new self::C::•().{self::C::m}<core::int*>(42){(core::int*) →* core::int*};
+}
diff --git a/pkg/front_end/testcases/inference/infer_getter_cross_to_setter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_getter_cross_to_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..b45aed1
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_getter_cross_to_setter.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract set x(core::double* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  abstract get x() → core::double*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_getter_from_later_inferred_getter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_getter_from_later_inferred_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..a1ce381
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_getter_from_later_inferred_getter.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object implements self::B {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  get x() → core::int*
+    return self::f() as{TypeError,ForDynamic} core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object implements self::C {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f() → dynamic
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_list_literal_nested_in_map_literal.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_list_literal_nested_in_map_literal.dart.weak.modular.expect
new file mode 100644
index 0000000..74ddf33
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_list_literal_nested_in_map_literal.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Resource extends core::Object {
+  synthetic constructor •() → self::Resource*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Folder extends self::Resource {
+  synthetic constructor •() → self::Folder*
+    : super self::Resource::•()
+    ;
+}
+class Foo<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(self::Foo::T* t) → self::Foo<self::Foo::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method getResource(core::String* str) → self::Resource*
+  return null;
+static method main() → dynamic {
+  core::Map<core::String*, core::List<self::Folder*>*>* map = <core::String*, core::List<self::Folder*>*>{"pkgA": <self::Folder*>[self::getResource("/pkgA/lib/") as{TypeError} self::Folder*], "pkgB": <self::Folder*>[self::getResource("/pkgB/lib/") as{TypeError} self::Folder*]};
+  core::List<core::Map<core::String*, self::Folder*>*>* list = <core::Map<core::String*, self::Folder*>*>[<core::String*, self::Folder*>{"pkgA": self::getResource("/pkgA/lib/") as{TypeError} self::Folder*}, <core::String*, self::Folder*>{"pkgB": self::getResource("/pkgB/lib/") as{TypeError} self::Folder*}];
+  self::Foo<core::List<self::Folder*>*>* foo = new self::Foo::•<core::List<self::Folder*>*>(<self::Folder*>[self::getResource("/pkgA/lib/") as{TypeError} self::Folder*]);
+}
diff --git a/pkg/front_end/testcases/inference/infer_local_function_referenced_before_declaration.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_local_function_referenced_before_declaration.dart.weak.modular.expect
new file mode 100644
index 0000000..588ca83
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_local_function_referenced_before_declaration.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_local_function_referenced_before_declaration.dart:9:79: Error: Method not found: 'g'.
+//   /*@returnType=invalid-type*/ f() => /*error:REFERENCED_BEFORE_DECLARATION*/ g();
+//                                                                               ^
+//
+// pkg/front_end/testcases/inference/infer_local_function_referenced_before_declaration.dart:14:3: Error: Can't declare 'g' because it was already used in this scope.
+//   g() => 0;
+//   ^
+// pkg/front_end/testcases/inference/infer_local_function_referenced_before_declaration.dart:9:79: Context: Previous use of 'g'.
+//   /*@returnType=invalid-type*/ f() => /*error:REFERENCED_BEFORE_DECLARATION*/ g();
+//                                                                               ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test() → dynamic {
+  function f() → invalid-type
+    return invalid-expression "pkg/front_end/testcases/inference/infer_local_function_referenced_before_declaration.dart:9:79: Error: Method not found: 'g'.
+  /*@returnType=invalid-type*/ f() => /*error:REFERENCED_BEFORE_DECLARATION*/ g();
+                                                                              ^";
+  {
+    invalid-expression "pkg/front_end/testcases/inference/infer_local_function_referenced_before_declaration.dart:14:3: Error: Can't declare 'g' because it was already used in this scope.
+  g() => 0;
+  ^";
+    function g() → core::int*
+      return 0;
+  }
+  () →* invalid-type v = f;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_local_function_return_type.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_local_function_return_type.dart.weak.modular.expect
new file mode 100644
index 0000000..eb05a20
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_local_function_return_type.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+static method test() → dynamic {
+  function f0() → core::int*
+    return 42;
+  function f1() → asy::Future<core::int*>* async 
+    return 42;
+  function f2() → core::int* {
+    return 42;
+  }
+  function f3() → asy::Future<core::int*>* async {
+    return 42;
+  }
+  function f4() → core::Iterable<core::int*>* sync* {
+    yield 42;
+  }
+  function f5() → asy::Stream<core::int*>* async* {
+    yield 42;
+  }
+  function f6() → core::num*
+    return 42;
+  function f7() → dynamic
+    return f7(){() →* dynamic};
+  function f8() → asy::Stream<core::int*>*
+    return f5(){() →* asy::Stream<core::int*>*};
+  () →* core::int* v0 = f0;
+  () →* asy::Future<core::int*>* v1 = f1;
+  () →* core::int* v2 = f2;
+  () →* asy::Future<core::int*>* v3 = f3;
+  () →* core::Iterable<core::int*>* v4 = f4;
+  () →* asy::Stream<core::int*>* v5 = f5;
+  () →* core::num* v6 = f6;
+  () →* dynamic v7 = f7;
+  () →* asy::Stream<core::int*>* v8 = f8;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_method_function_typed.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_method_function_typed.dart.weak.modular.expect
new file mode 100644
index 0000000..abae228
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_method_function_typed.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F = () →* core::int*;
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract method x(() →* core::int* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  abstract method x(() →* dynamic value) → void;
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method g(self::B* b) → dynamic {
+  b.{self::B::x}(self::f<() →* dynamic>()){(() →* dynamic) →* void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_method_missing_params.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_method_missing_params.dart.weak.modular.expect
new file mode 100644
index 0000000..4b3051b
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_method_missing_params.dart.weak.modular.expect
@@ -0,0 +1,98 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_method_missing_params.dart:25:3: Error: Can't infer types for 'f' as the overridden members don't have a combined signature.
+// Try adding explicit types.
+//   f(x, y);
+//   ^
+// pkg/front_end/testcases/inference/infer_method_missing_params.dart:11:7: Context: This is one of the overridden members.
+//   int f(int x, int y);
+//       ^
+// pkg/front_end/testcases/inference/infer_method_missing_params.dart:18:7: Context: This is one of the overridden members.
+//   int f(int x);
+//       ^
+//
+// pkg/front_end/testcases/inference/infer_method_missing_params.dart:28:3: Error: Can't infer types for 'i' as the overridden members don't have a combined signature.
+// Try adding explicit types.
+//   i(x, {y, z});
+//   ^
+// pkg/front_end/testcases/inference/infer_method_missing_params.dart:14:7: Context: This is one of the overridden members.
+//   int i(int x, {int y});
+//       ^
+// pkg/front_end/testcases/inference/infer_method_missing_params.dart:21:7: Context: This is one of the overridden members.
+//   int i(int x, {int z});
+//       ^
+//
+// pkg/front_end/testcases/inference/infer_method_missing_params.dart:25:3: Error: The method 'C.f' has more required arguments than those of overridden method 'B.f'.
+//   f(x, y);
+//   ^
+// pkg/front_end/testcases/inference/infer_method_missing_params.dart:18:7: Context: This is the overridden method ('f').
+//   int f(int x);
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract method f(core::int* x, core::int* y) → core::int*;
+  abstract method g(core::int* x, [core::int* y = #C1]) → core::int*;
+  abstract method h(core::int* x, {core::int* y = #C1}) → core::int*;
+  abstract method i(core::int* x, {core::int* y = #C1}) → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract method f(core::int* x) → core::int*;
+  abstract method g(core::int* x) → core::int*;
+  abstract method h(core::int* x) → core::int*;
+  abstract method i(core::int* x, {core::int* z = #C1}) → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object implements self::A, self::B {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract method f(invalid-type x, invalid-type y) → invalid-type;
+  abstract method g(core::int* x, [core::int* y = #C1]) → core::int*;
+  abstract method h(core::int* x, {core::int* y = #C1}) → core::int*;
+  abstract method i(invalid-type x, {invalid-type y = #C1, invalid-type z = #C1}) → invalid-type;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/inference/infer_parameter_type_setter_from_field.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_parameter_type_setter_from_field.dart.weak.modular.expect
new file mode 100644
index 0000000..516ea9a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_parameter_type_setter_from_field.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends self::D {
+  synthetic constructor •() → self::C*
+    : super self::D::•()
+    ;
+  set foo(core::int* x) → void {}
+}
+class D extends core::Object {
+  field core::int* foo = null;
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_parameter_type_setter_from_setter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_parameter_type_setter_from_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..84b9408
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_parameter_type_setter_from_setter.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends self::D {
+  synthetic constructor •() → self::C*
+    : super self::D::•()
+    ;
+  set foo(core::int* x) → void {}
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  set foo(core::int* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_prefix_expression.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_prefix_expression.dart.weak.modular.expect
new file mode 100644
index 0000000..ec7b742
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_prefix_expression.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::bool* a_not = !true;
+static field core::int* a_complement = 1.{core::int::~}(){() →* core::int*};
+static field core::int* a_negate = 1.{core::int::unary-}(){() →* core::int*};
+static method main() → dynamic {
+  self::a_not;
+  self::a_complement;
+  self::a_negate;
+}
diff --git a/pkg/front_end/testcases/inference/infer_prefix_expression_custom.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_prefix_expression_custom.dart.weak.modular.expect
new file mode 100644
index 0000000..2c6f832
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_prefix_expression_custom.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator ~() → core::int*
+    return 1;
+  operator unary-() → core::double*
+    return 2.0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::A* a = new self::A::•();
+static field core::int* v_complement = self::a.{self::A::~}(){() →* core::int*};
+static field core::double* v_negate = self::a.{self::A::unary-}(){() →* core::double*};
+static method main() → dynamic {
+  self::a;
+  self::v_complement;
+  self::v_negate;
+}
diff --git a/pkg/front_end/testcases/inference/infer_rethrow.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_rethrow.dart.weak.modular.expect
new file mode 100644
index 0000000..1e36c8b
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_rethrow.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library test;
+import self as self;
+
+static method test(() →* dynamic f, () →* dynamic g) → dynamic {
+  try {
+    f(){() →* dynamic};
+  }
+  on dynamic catch(final dynamic _) {
+    g(){() →* dynamic};
+    rethrow;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_return_of_statement_lambda.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_return_of_statement_lambda.dart.weak.modular.expect
new file mode 100644
index 0000000..cdbf9e5
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_return_of_statement_lambda.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method strings() → core::List<core::String*>* {
+  core::Iterable<core::String*>* stuff = <dynamic>[].{core::Iterable::expand}<core::String*>((dynamic i) → core::List<core::String*>* {
+    return <core::String*>[];
+  }){((dynamic) →* core::Iterable<core::String*>*) →* core::Iterable<core::String*>*};
+  return stuff.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<core::String*>*};
+}
+static method main() → dynamic {
+  self::strings();
+}
diff --git a/pkg/front_end/testcases/inference/infer_return_type_for_static_setter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_return_type_for_static_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..3259075
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_return_type_for_static_setter.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  static set foo(core::int* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static set bar(core::int* x) → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_setter_cross_to_getter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_setter_cross_to_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..8778884
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_setter_cross_to_getter.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::double*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  abstract set x(core::double* value) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_setter_from_later_inferred_setter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_setter_from_later_inferred_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..70ec7fa
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_setter_from_later_inferred_setter.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object implements self::B {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  set x(core::int* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object implements self::C {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract set x(core::int* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract set x(core::int* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_setter_function_typed.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_setter_function_typed.dart.weak.modular.expect
new file mode 100644
index 0000000..6c97fd8
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_setter_function_typed.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F = () →* core::int*;
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract set x(() →* core::int* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  abstract set x(() →* dynamic value) → void;
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method g(self::B* b) → dynamic {
+  b.{self::B::x} = self::f<() →* dynamic>();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_setter_return_type_only.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_setter_return_type_only.dart.weak.modular.expect
new file mode 100644
index 0000000..a14272b
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_setter_return_type_only.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  set x(core::int* i) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  set x(core::Object* o) → void {}
+}
+static method main() → dynamic {
+  new self::B::•().{self::B::x} = "hello";
+}
diff --git a/pkg/front_end/testcases/inference/infer_statics_transitively.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_statics_transitively.dart.weak.modular.expect
new file mode 100644
index 0000000..445bbcb
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_statics_transitively.dart.weak.modular.expect
@@ -0,0 +1,51 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "infer_statics_transitively_a.dart" as inf;
+
+import "org-dartlang-testcase:///infer_statics_transitively_a.dart";
+
+static final field core::int* m1 = inf::a1;
+static final field core::int* m2 = inf::A::a2;
+static method foo() → dynamic {
+  core::int* i;
+  i = self::m1;
+}
+static method main() → dynamic {}
+
+library;
+import self as inf;
+import "dart:core" as core;
+import "infer_statics_transitively_b.dart" as inf2;
+import "infer_statics_transitively.dart" as self;
+
+import "org-dartlang-testcase:///infer_statics_transitively.dart";
+import "org-dartlang-testcase:///infer_statics_transitively_b.dart";
+
+class A extends core::Object {
+  static final field core::int* a2 = inf2::b1;
+  synthetic constructor •() → inf::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static final field core::int* a1 = self::m2;
+static method main() → dynamic {}
+
+library;
+import self as inf2;
+import "dart:core" as core;
+
+static final field core::int* b1 = 2;
+static method main() → dynamic {
+  inf2::b1;
+}
diff --git a/pkg/front_end/testcases/inference/infer_statics_transitively2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_statics_transitively2.dart.weak.modular.expect
new file mode 100644
index 0000000..a530b9e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_statics_transitively2.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static const field core::int* x1 = #C1;
+static final field core::int* x2 = 1;
+static final field core::int* y1 = #C1;
+static final field core::int* y2 = self::x2;
+static method foo() → dynamic {
+  core::int* i;
+  i = self::y1;
+  i = self::y2;
+}
+static method main() → dynamic {
+  self::foo();
+}
+
+constants  {
+  #C1 = 1
+}
diff --git a/pkg/front_end/testcases/inference/infer_statics_transitively3.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_statics_transitively3.dart.weak.modular.expect
new file mode 100644
index 0000000..0f736d7
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_statics_transitively3.dart.weak.modular.expect
@@ -0,0 +1,52 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///infer_statics_transitively3_a.dart" show a1, A;
+import "org-dartlang-testcase:///infer_statics_transitively3_a.dart" as p show a2, A;
+
+static const field core::int* t1 = #C1;
+static const field core::int* t2 = #C1;
+static const field core::int* t3 = #C2;
+static const field core::int* t4 = #C3;
+static const field dynamic t5 = #C4;
+static const field dynamic t6 = #C4;
+static method foo() → dynamic {
+  core::int* i;
+  i = #C1;
+  i = #C1;
+  i = #C2;
+  i = #C3;
+}
+static method main() → dynamic {}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+class A extends core::Object {
+  static const field dynamic a3 = #C4;
+  synthetic constructor •() → self2::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field core::int* a1 = #C2;
+static const field core::int* a2 = #C3;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 1
+  #C2 = 3
+  #C3 = 4
+  #C4 = null
+}
diff --git a/pkg/front_end/testcases/inference/infer_statics_transitively3_a.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_statics_transitively3_a.dart.weak.modular.expect
new file mode 100644
index 0000000..a54e7ab
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_statics_transitively3_a.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  static const field dynamic a3 = #C1;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field core::int* a1 = #C2;
+static const field core::int* a2 = #C3;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = 3
+  #C3 = 4
+}
diff --git a/pkg/front_end/testcases/inference/infer_statics_transitively_2_a.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_statics_transitively_2_a.dart.weak.modular.expect
new file mode 100644
index 0000000..54b40b9
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_statics_transitively_2_a.dart.weak.modular.expect
@@ -0,0 +1,81 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "infer_statics_transitively_b.dart" as inf;
+import "infer_statics_transitively.dart" as test;
+
+import "org-dartlang-testcase:///infer_statics_transitively.dart";
+import "org-dartlang-testcase:///infer_statics_transitively_b.dart";
+
+class A extends core::Object {
+  static final field core::int* a2 = inf::b1;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static final field core::int* a1 = test::m2;
+static method main() → dynamic {
+  self::a1;
+}
+
+library test;
+import self as test;
+import "dart:core" as core;
+import "infer_statics_transitively_a.dart" as inf2;
+
+import "org-dartlang-testcase:///infer_statics_transitively_a.dart";
+
+static final field core::int* m1 = inf2::a1;
+static final field core::int* m2 = inf2::A::a2;
+static method foo() → dynamic {
+  core::int* i;
+  i = test::m1;
+}
+static method main() → dynamic {}
+
+library;
+import self as inf;
+import "dart:core" as core;
+
+static final field core::int* b1 = 2;
+static method main() → dynamic {
+  inf::b1;
+}
+
+library;
+import self as inf2;
+import "dart:core" as core;
+import "infer_statics_transitively_b.dart" as inf;
+import "infer_statics_transitively.dart" as test;
+
+import "org-dartlang-testcase:///infer_statics_transitively.dart";
+import "org-dartlang-testcase:///infer_statics_transitively_b.dart";
+
+class A extends core::Object {
+  static final field core::int* a2 = inf::b1;
+  synthetic constructor •() → inf2::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static final field core::int* a1 = test::m2;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_statics_transitively_a.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_statics_transitively_a.dart.weak.modular.expect
new file mode 100644
index 0000000..327bcc1
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_statics_transitively_a.dart.weak.modular.expect
@@ -0,0 +1,51 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "infer_statics_transitively_b.dart" as inf;
+import "infer_statics_transitively.dart" as test;
+
+import "org-dartlang-testcase:///infer_statics_transitively.dart";
+import "org-dartlang-testcase:///infer_statics_transitively_b.dart";
+
+class A extends core::Object {
+  static final field core::int* a2 = inf::b1;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static final field core::int* a1 = test::m2;
+static method main() → dynamic {}
+
+library test;
+import self as test;
+import "dart:core" as core;
+import "infer_statics_transitively_a.dart" as self;
+
+import "org-dartlang-testcase:///infer_statics_transitively_a.dart";
+
+static final field core::int* m1 = self::a1;
+static final field core::int* m2 = self::A::a2;
+static method foo() → dynamic {
+  core::int* i;
+  i = test::m1;
+}
+static method main() → dynamic {}
+
+library;
+import self as inf;
+import "dart:core" as core;
+
+static final field core::int* b1 = 2;
+static method main() → dynamic {
+  inf::b1;
+}
diff --git a/pkg/front_end/testcases/inference/infer_statics_transitively_b.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_statics_transitively_b.dart.weak.modular.expect
new file mode 100644
index 0000000..8c80bfe
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_statics_transitively_b.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static final field core::int* b1 = 2;
+static method main() → dynamic {
+  self::b1;
+}
diff --git a/pkg/front_end/testcases/inference/infer_statics_with_method_invocations.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_statics_with_method_invocations.dart.weak.modular.expect
new file mode 100644
index 0000000..4a992cd
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_statics_with_method_invocations.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "infer_statics_with_method_invocations_a.dart" as inf;
+
+import "org-dartlang-testcase:///infer_statics_with_method_invocations_a.dart";
+
+class T extends core::Object {
+  static final field self::T* foo = self::T::m1(self::T::m2(inf::m3("", "")));
+  synthetic constructor •() → self::T*
+    : super core::Object::•()
+    ;
+  static method m1(core::String* m) → self::T* {
+    return null;
+  }
+  static method m2(dynamic e) → core::String* {
+    return "";
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+library;
+import self as inf;
+import "dart:core" as core;
+
+static method m3(core::String* a, core::String* b, [dynamic a1 = #C1, dynamic a2 = #C1]) → dynamic {}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/inference/infer_statics_with_method_invocations_a.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_statics_with_method_invocations_a.dart.weak.modular.expect
new file mode 100644
index 0000000..e864516
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_statics_with_method_invocations_a.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method m3(core::String* a, core::String* b, [dynamic a1 = #C1, dynamic a2 = #C1]) → dynamic {}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/inference/infer_throw.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_throw.dart.weak.modular.expect
new file mode 100644
index 0000000..8f6f2b1
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_throw.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::bool* t = true;
+static field dynamic a = throw 0;
+static field core::int* b = (throw 0) ?{core::int*} 1 : 2;
+static field core::int* c = self::t ?{core::int*} throw 1 : 2;
+static field core::int* d = self::t ?{core::int*} 1 : throw 2;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_throw_downwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_throw_downwards.dart.weak.modular.expect
new file mode 100644
index 0000000..e583c2a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_throw_downwards.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field dynamic x = throw self::f<dynamic>();
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method g() → void {
+  dynamic x = throw self::f<dynamic>();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_type_on_overridden_fields2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_type_on_overridden_fields2.dart.weak.modular.expect
new file mode 100644
index 0000000..454f2de
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_type_on_overridden_fields2.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_type_on_overridden_fields2.dart:17:68: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   String y = /*error:INVALID_ASSIGNMENT*/ new B(). /*@target=B.x*/ x;
+//                                                                    ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* x = 2;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  get x() → core::int*
+    return 3;
+}
+static method foo() → dynamic {
+  core::String* y = invalid-expression "pkg/front_end/testcases/inference/infer_type_on_overridden_fields2.dart:17:68: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  String y = /*error:INVALID_ASSIGNMENT*/ new B(). /*@target=B.x*/ x;
+                                                                   ^" in new self::B::•().{self::B::x}{core::int*} as{TypeError} core::String*;
+  core::int* z = new self::B::•().{self::B::x}{core::int*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_type_on_overridden_fields4.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_type_on_overridden_fields4.dart.weak.modular.expect
new file mode 100644
index 0000000..a8b5b21
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_type_on_overridden_fields4.dart.weak.modular.expect
@@ -0,0 +1,51 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_type_on_overridden_fields4.dart:17:68: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   String y = /*error:INVALID_ASSIGNMENT*/ new B(). /*@target=B.x*/ x;
+//                                                                    ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  final field core::int* x = 2;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::A {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  get x() → core::int*
+    return 3;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo() → dynamic {
+  core::String* y = invalid-expression "pkg/front_end/testcases/inference/infer_type_on_overridden_fields4.dart:17:68: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  String y = /*error:INVALID_ASSIGNMENT*/ new B(). /*@target=B.x*/ x;
+                                                                   ^" in new self::B::•().{self::B::x}{core::int*} as{TypeError} core::String*;
+  core::int* z = new self::B::•().{self::B::x}{core::int*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_type_on_var.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_type_on_var.dart.weak.modular.expect
new file mode 100644
index 0000000..be69c0e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_type_on_var.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_type_on_var.dart:10:36: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   x = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                    ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test1() → dynamic {
+  core::int* x = 3;
+  x = invalid-expression "pkg/front_end/testcases/inference/infer_type_on_var.dart:10:36: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  x = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                   ^" in "hi" as{TypeError} core::int*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_type_on_var2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_type_on_var2.dart.weak.modular.expect
new file mode 100644
index 0000000..318a2d0
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_type_on_var2.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_type_on_var2.dart:10:36: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   x = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                    ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test2() → dynamic {
+  core::int* x = 3;
+  x = invalid-expression "pkg/front_end/testcases/inference/infer_type_on_var2.dart:10:36: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  x = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                   ^" in "hi" as{TypeError} core::int*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_type_on_var_from_field.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_type_on_var_from_field.dart.weak.modular.expect
new file mode 100644
index 0000000..f622139
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_type_on_var_from_field.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_type_on_var_from_field.dart:13:38: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     a = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                      ^
+//
+// pkg/front_end/testcases/inference/infer_type_on_var_from_field.dart:16:38: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     b = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                      ^
+//
+// pkg/front_end/testcases/inference/infer_type_on_var_from_field.dart:19:38: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//     c = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                      ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* x = 0;
+  field core::int* y = null;
+  final field core::int* z = 42;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method test1() → dynamic {
+    core::int* a = this.{self::A::x}{core::int*};
+    a = invalid-expression "pkg/front_end/testcases/inference/infer_type_on_var_from_field.dart:13:38: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    a = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                     ^" in "hi" as{TypeError} core::int*;
+    a = 3;
+    core::int* b = this.{self::A::y}{core::int*};
+    b = invalid-expression "pkg/front_end/testcases/inference/infer_type_on_var_from_field.dart:16:38: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    b = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                     ^" in "hi" as{TypeError} core::int*;
+    b = 4;
+    core::int* c = this.{self::A::z}{core::int*};
+    c = invalid-expression "pkg/front_end/testcases/inference/infer_type_on_var_from_field.dart:19:38: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+    c = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                     ^" in "hi" as{TypeError} core::int*;
+    c = 4;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_type_on_var_from_top_level.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_type_on_var_from_top_level.dart.weak.modular.expect
new file mode 100644
index 0000000..63aa12a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_type_on_var_from_top_level.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_type_on_var_from_top_level.dart:12:36: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   a = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                    ^
+//
+// pkg/front_end/testcases/inference/infer_type_on_var_from_top_level.dart:15:36: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   b = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                    ^
+//
+// pkg/front_end/testcases/inference/infer_type_on_var_from_top_level.dart:18:36: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   c = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                    ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field core::int* x = 0;
+static field core::int* y = 0;
+static final field core::int* z = 42;
+static method test1() → dynamic {
+  core::int* a = self::x;
+  a = invalid-expression "pkg/front_end/testcases/inference/infer_type_on_var_from_top_level.dart:12:36: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  a = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                   ^" in "hi" as{TypeError} core::int*;
+  a = 3;
+  core::int* b = self::y;
+  b = invalid-expression "pkg/front_end/testcases/inference/infer_type_on_var_from_top_level.dart:15:36: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  b = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                   ^" in "hi" as{TypeError} core::int*;
+  b = 4;
+  core::int* c = self::z;
+  c = invalid-expression "pkg/front_end/testcases/inference/infer_type_on_var_from_top_level.dart:18:36: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  c = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                   ^" in "hi" as{TypeError} core::int*;
+  c = 4;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_type_regardless_of_declaration_order_or_cycles.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_type_regardless_of_declaration_order_or_cycles.dart.weak.modular.expect
new file mode 100644
index 0000000..dced83d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_type_regardless_of_declaration_order_or_cycles.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_type_regardless_of_declaration_order_or_cycles.dart:20:68: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   String z = /*error:INVALID_ASSIGNMENT*/ new C(). /*@target=C.x*/ x;
+//                                                                    ^
+//
+import self as self;
+import "infer_type_regardless_of_declaration_order_or_cycles_b.dart" as inf;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///infer_type_regardless_of_declaration_order_or_cycles_b.dart";
+
+class C extends inf::B {
+  synthetic constructor •() → self::C*
+    : super inf::B::•()
+    ;
+  get x() → core::int*
+    return null;
+}
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  get x() → core::int*
+    return 0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo() → dynamic {
+  core::int* y = new self::C::•().{self::C::x}{core::int*};
+  core::String* z = invalid-expression "pkg/front_end/testcases/inference/infer_type_regardless_of_declaration_order_or_cycles.dart:20:68: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  String z = /*error:INVALID_ASSIGNMENT*/ new C(). /*@target=C.x*/ x;
+                                                                   ^" in new self::C::•().{self::C::x}{core::int*} as{TypeError} core::String*;
+}
+static method main() → dynamic {
+  self::foo();
+}
+
+library;
+import self as inf;
+import "infer_type_regardless_of_declaration_order_or_cycles.dart" as self;
+
+import "org-dartlang-testcase:///infer_type_regardless_of_declaration_order_or_cycles.dart";
+
+class B extends self::A {
+  synthetic constructor •() → inf::B*
+    : super self::A::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_type_regardless_of_declaration_order_or_cycles_b.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_type_regardless_of_declaration_order_or_cycles_b.dart.weak.modular.expect
new file mode 100644
index 0000000..0acdfbf
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_type_regardless_of_declaration_order_or_cycles_b.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library;
+import self as self;
+import "infer_type_regardless_of_declaration_order_or_cycles.dart" as test;
+
+import "org-dartlang-testcase:///infer_type_regardless_of_declaration_order_or_cycles.dart";
+
+class B extends test::A {
+  synthetic constructor •() → self::B*
+    : super test::A::•()
+    ;
+}
+static method main() → dynamic {}
+
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_type_regardless_of_declaration_order_or_cycles.dart:20:68: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   String z = /*error:INVALID_ASSIGNMENT*/ new C(). /*@target=C.x*/ x;
+//                                                                    ^
+//
+import self as test;
+import "infer_type_regardless_of_declaration_order_or_cycles_b.dart" as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///infer_type_regardless_of_declaration_order_or_cycles_b.dart";
+
+class C extends self::B {
+  synthetic constructor •() → test::C*
+    : super self::B::•()
+    ;
+  get x() → core::int*
+    return null;
+}
+class A extends core::Object {
+  synthetic constructor •() → test::A*
+    : super core::Object::•()
+    ;
+  get x() → core::int*
+    return 0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo() → dynamic {
+  core::int* y = new test::C::•().{test::C::x}{core::int*};
+  core::String* z = invalid-expression "pkg/front_end/testcases/inference/infer_type_regardless_of_declaration_order_or_cycles.dart:20:68: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  String z = /*error:INVALID_ASSIGNMENT*/ new C(). /*@target=C.x*/ x;
+                                                                   ^" in new test::C::•().{test::C::x}{core::int*} as{TypeError} core::String*;
+}
+static method main() → dynamic {
+  test::foo();
+}
diff --git a/pkg/front_end/testcases/inference/infer_typed_map_literal.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_typed_map_literal.dart.weak.modular.expect
new file mode 100644
index 0000000..a416db2
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_typed_map_literal.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::Map<core::int*, core::String*>* a = <core::int*, core::String*>{0: "aaa", 1: "bbb"};
+static field core::Map<core::double*, core::int*>* b = <core::double*, core::int*>{1.1: 1, 2.2: 2};
+static field core::Map<core::List<core::int*>*, core::Map<core::String*, core::double*>*>* c = <core::List<core::int*>*, core::Map<core::String*, core::double*>*>{};
+static field core::Map<core::int*, dynamic>* d = <core::int*, dynamic>{};
+static field core::Map<dynamic, core::int*>* e = <dynamic, core::int*>{};
+static field core::Map<dynamic, dynamic>* f = <dynamic, dynamic>{};
+static method main() → dynamic {
+  self::a;
+  self::b;
+  self::c;
+  self::d;
+  self::e;
+  self::f;
+}
diff --git a/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_3.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_3.dart.weak.modular.expect
new file mode 100644
index 0000000..a263f07
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_3.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_3.dart:15:45: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   get w => /*error:RETURN_OF_INVALID_TYPE*/ "hello";
+//                                             ^
+//
+// pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_3.dart:19:68: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   String y = /*error:INVALID_ASSIGNMENT*/ new B(). /*@target=B.x*/ x;
+//                                                                    ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  final field self::A::T* x = null;
+  final field self::A::T* w = null;
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::A<core::int*> {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  get x() → core::int*
+    return 3;
+  get w() → core::int*
+    return invalid-expression "pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_3.dart:15:45: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  get w => /*error:RETURN_OF_INVALID_TYPE*/ \"hello\";
+                                            ^" in "hello" as{TypeError} core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo() → dynamic {
+  core::String* y = invalid-expression "pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_3.dart:19:68: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  String y = /*error:INVALID_ASSIGNMENT*/ new B(). /*@target=B.x*/ x;
+                                                                   ^" in new self::B::•().{self::B::x}{core::int*} as{TypeError} core::String*;
+  core::int* z = new self::B::•().{self::B::x}{core::int*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_4.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_4.dart.weak.modular.expect
new file mode 100644
index 0000000..4e199e1
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_4.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_4.dart:18:73: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   int y = /*error:INVALID_ASSIGNMENT*/ new B<String>(). /*@target=B.x*/ x;
+//                                                                         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::A::T* x = null;
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<E extends core::Object* = dynamic> extends self::A<self::B::E*> {
+  covariant-by-class field self::B::E* y = null;
+  synthetic constructor •() → self::B<self::B::E*>*
+    : super self::A::•()
+    ;
+  get x() → self::B::E*
+    return this.{self::B::y}{self::B::E*};
+}
+static method foo() → dynamic {
+  core::int* y = invalid-expression "pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_4.dart:18:73: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  int y = /*error:INVALID_ASSIGNMENT*/ new B<String>(). /*@target=B.x*/ x;
+                                                                        ^" in new self::B::•<core::String*>().{self::B::x}{core::String*} as{TypeError} core::int*;
+  core::String* z = new self::B::•<core::String*>().{self::B::x}{core::String*};
+}
+static method main() → dynamic {
+  self::foo();
+}
diff --git a/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_5.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_5.dart.weak.modular.expect
new file mode 100644
index 0000000..5b19a39
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_5.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_5.dart:30:25: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       . /*@target=B.m*/ m(null, null);
+//                         ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class I<E extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::E*>*
+    : super core::Object::•()
+    ;
+  abstract method m(dynamic a, (dynamic, self::I::E*) →* core::String* f) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class A<E extends core::Object* = dynamic> extends core::Object implements self::I<self::A::E*> /*hasConstConstructor*/  {
+  const constructor •() → self::A<self::A::E*>*
+    : super core::Object::•()
+    ;
+  abstract method m(dynamic a, (dynamic, self::A::E*) →* core::String* f) → core::String*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M extends core::Object {
+  final field core::int* y = 0;
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<E extends core::Object* = dynamic> extends self::A<self::B::E*> implements self::M /*hasConstConstructor*/  {
+  const constructor •() → self::B<self::B::E*>*
+    : super self::A::•()
+    ;
+  get y() → core::int*
+    return 0;
+  method m(dynamic a, (dynamic, self::B::E*) →* dynamic f) → core::String* {}
+}
+static method foo() → dynamic {
+  core::int* y = invalid-expression "pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_5.dart:30:25: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      . /*@target=B.m*/ m(null, null);
+                        ^" in new self::B::•<dynamic>().{self::B::m}(null, null){(dynamic, (dynamic, dynamic) →* dynamic) →* core::String*} as{TypeError} core::int*;
+  core::String* z = new self::B::•<dynamic>().{self::B::m}(null, null){(dynamic, (dynamic, dynamic) →* dynamic) →* core::String*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_in_library_cycle.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_in_library_cycle.dart.weak.modular.expect
new file mode 100644
index 0000000..27f0da3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_in_library_cycle.dart.weak.modular.expect
@@ -0,0 +1,86 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_in_library_cycle.dart:30:29: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       . /*@target=A.value*/ value;
+//                             ^
+//
+import self as self;
+import "dart:core" as core;
+import "infer_types_on_generic_instantiations_in_library_cycle_a.dart" as inf;
+
+import "org-dartlang-testcase:///infer_types_on_generic_instantiations_in_library_cycle_a.dart";
+
+abstract class A<E extends core::Object* = dynamic> extends core::Object implements inf::I<self::A::E*> /*hasConstConstructor*/  {
+  final field self::A::E* value = null;
+  const constructor •() → self::A<self::A::E*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M extends core::Object {
+  final field core::int* y = 0;
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<E extends core::Object* = dynamic> extends self::A<self::B::E*> implements self::M /*hasConstConstructor*/  {
+  const constructor •() → self::B<self::B::E*>*
+    : super self::A::•()
+    ;
+  get y() → core::int*
+    return 0;
+  method m(dynamic a, (dynamic, core::int*) →* dynamic f) → self::A<self::B::E*>* {}
+}
+static method foo() → dynamic {
+  core::int* y = invalid-expression "pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_in_library_cycle.dart:30:29: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      . /*@target=A.value*/ value;
+                            ^" in new self::B::•<core::String*>().{self::B::m}(null, null){(dynamic, (dynamic, core::int*) →* dynamic) →* self::A<core::String*>*}.{self::A::value}{core::String*} as{TypeError} core::int*;
+  core::String* z = new self::B::•<core::String*>().{self::B::m}(null, null){(dynamic, (dynamic, core::int*) →* dynamic) →* self::A<core::String*>*}.{self::A::value}{core::String*};
+}
+static method main() → dynamic {}
+
+library;
+import self as inf;
+import "dart:core" as core;
+import "infer_types_on_generic_instantiations_in_library_cycle.dart" as self;
+
+import "org-dartlang-testcase:///infer_types_on_generic_instantiations_in_library_cycle.dart";
+
+abstract class I<E extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → inf::I<inf::I::E*>*
+    : super core::Object::•()
+    ;
+  abstract method m(dynamic a, (dynamic, core::int*) →* core::String* f) → self::A<inf::I::E*>*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_in_library_cycle_a.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_in_library_cycle_a.dart.weak.modular.expect
new file mode 100644
index 0000000..e7555d5
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_in_library_cycle_a.dart.weak.modular.expect
@@ -0,0 +1,86 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "infer_types_on_generic_instantiations_in_library_cycle.dart" as test;
+
+import "org-dartlang-testcase:///infer_types_on_generic_instantiations_in_library_cycle.dart";
+
+abstract class I<E extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::E*>*
+    : super core::Object::•()
+    ;
+  abstract method m(dynamic a, (dynamic, core::int*) →* core::String* f) → test::A<self::I::E*>*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_in_library_cycle.dart:30:29: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       . /*@target=A.value*/ value;
+//                             ^
+//
+import self as test;
+import "dart:core" as core;
+import "infer_types_on_generic_instantiations_in_library_cycle_a.dart" as self;
+
+import "org-dartlang-testcase:///infer_types_on_generic_instantiations_in_library_cycle_a.dart";
+
+abstract class A<E extends core::Object* = dynamic> extends core::Object implements self::I<test::A::E*> /*hasConstConstructor*/  {
+  final field test::A::E* value = null;
+  const constructor •() → test::A<test::A::E*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M extends core::Object {
+  final field core::int* y = 0;
+  synthetic constructor •() → test::M*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<E extends core::Object* = dynamic> extends test::A<test::B::E*> implements test::M /*hasConstConstructor*/  {
+  const constructor •() → test::B<test::B::E*>*
+    : super test::A::•()
+    ;
+  get y() → core::int*
+    return 0;
+  method m(dynamic a, (dynamic, core::int*) →* dynamic f) → test::A<test::B::E*>* {}
+}
+static method foo() → dynamic {
+  core::int* y = invalid-expression "pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_in_library_cycle.dart:30:29: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      . /*@target=A.value*/ value;
+                            ^" in new test::B::•<core::String*>().{test::B::m}(null, null){(dynamic, (dynamic, core::int*) →* dynamic) →* test::A<core::String*>*}.{test::A::value}{core::String*} as{TypeError} core::int*;
+  core::String* z = new test::B::•<core::String*>().{test::B::m}(null, null){(dynamic, (dynamic, core::int*) →* dynamic) →* test::A<core::String*>*}.{test::A::value}{core::String*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_infer.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_infer.dart.weak.modular.expect
new file mode 100644
index 0000000..bd1fcf0
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_infer.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_infer.dart:13:49: Error: The return type of the method 'B.x' is 'dynamic', which does not match the return type, 'int', of the overridden method, 'A.x'.
+// Change to a subtype of 'int'.
+//   /*error:INVALID_METHOD_OVERRIDE*/ dynamic get x => 3;
+//                                                 ^
+// pkg/front_end/testcases/inference/infer_types_on_generic_instantiations_infer.dart:9:11: Context: This is the overridden method ('x').
+//   final T x = null;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  final field self::A::T* x = null;
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::A<core::int*> {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  get x() → dynamic
+    return 3;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo() → dynamic {
+  core::String* y = new self::B::•().{self::B::x}{dynamic} as{TypeError,ForDynamic} core::String*;
+  core::int* z = new self::B::•().{self::B::x}{dynamic} as{TypeError,ForDynamic} core::int*;
+}
+static method main() → dynamic {
+  self::foo();
+}
diff --git a/pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart.weak.modular.expect
new file mode 100644
index 0000000..680de12
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart.weak.modular.expect
@@ -0,0 +1,142 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart:15:44: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       int x = /*error:INVALID_ASSIGNMENT*/ i;
+//                                            ^
+//
+// pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart:23:44: Error: A value of type 'T' can't be assigned to a variable of type 'int'.
+//       int x = /*error:INVALID_ASSIGNMENT*/ i;
+//                                            ^
+//
+// pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart:32:45: Error: A value of type 'Foo' can't be assigned to a variable of type 'String'.
+//  - 'Foo' is from 'pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart'.
+//     String y = /*error:INVALID_ASSIGNMENT*/ x;
+//                                             ^
+//
+// pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart:39:15: Error: A value of type 'Foo' can't be assigned to a variable of type 'String'.
+//  - 'Foo' is from 'pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart'.
+// Try changing the type of the variable.
+//   for (String x in /*error:FOR_IN_OF_INVALID_ELEMENT_TYPE*/ list) {
+//               ^
+//
+// pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart:60:70: Error: The type 'Map<String, Foo>' used in the 'for' loop must implement 'Iterable<dynamic>'.
+//  - 'Map' is from 'dart:core'.
+//  - 'Foo' is from 'pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart'.
+//  - 'Iterable' is from 'dart:core'.
+//   for (var /*@ type=dynamic */ x in /*error:FOR_IN_OF_INVALID_TYPE*/ map) {
+//                                                                      ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  field core::int* bar = 42;
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar<T extends core::Iterable<core::String*>*> extends core::Object {
+  synthetic constructor •() → self::Bar<self::Bar::T*>*
+    : super core::Object::•()
+    ;
+  method foo(covariant-by-class self::Bar::T* t) → void {
+    for (core::String* i in t) {
+      core::int* x = invalid-expression "pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart:15:44: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      int x = /*error:INVALID_ASSIGNMENT*/ i;
+                                           ^" in i as{TypeError} core::int*;
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Baz<T extends core::Object* = dynamic, E extends core::Iterable<self::Baz::T*>* = core::Iterable<dynamic>*, S extends self::Baz::E* = core::Iterable<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::Baz<self::Baz::T*, self::Baz::E*, self::Baz::S*>*
+    : super core::Object::•()
+    ;
+  method foo(covariant-by-class self::Baz::S* t) → void {
+    for (self::Baz::T* i in t) {
+      core::int* x = invalid-expression "pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart:23:44: Error: A value of type 'T' can't be assigned to a variable of type 'int'.
+      int x = /*error:INVALID_ASSIGNMENT*/ i;
+                                           ^" in i as{TypeError} core::int*;
+      self::Baz::T* y = i;
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  core::List<self::Foo*>* list = <self::Foo*>[];
+  for (self::Foo* x in list) {
+    core::String* y = invalid-expression "pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart:32:45: Error: A value of type 'Foo' can't be assigned to a variable of type 'String'.
+ - 'Foo' is from 'pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart'.
+    String y = /*error:INVALID_ASSIGNMENT*/ x;
+                                            ^" in x as{TypeError} core::String*;
+  }
+  for (dynamic x in list) {
+    core::String* y = x as{TypeError,ForDynamic} core::String*;
+  }
+  for (final self::Foo* #t1 in list) {
+    core::String* x = invalid-expression "pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart:39:15: Error: A value of type 'Foo' can't be assigned to a variable of type 'String'.
+ - 'Foo' is from 'pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart'.
+Try changing the type of the variable.
+  for (String x in /*error:FOR_IN_OF_INVALID_ELEMENT_TYPE*/ list) {
+              ^" in #t1 as{TypeError} core::String*;
+    core::String* y = x;
+  }
+  dynamic z;
+  for (final self::Foo* #t2 in list) {
+    z = #t2;
+    core::String* y = z as{TypeError,ForDynamic} core::String*;
+  }
+  core::Iterable<dynamic>* iter = list;
+  for (final dynamic #t3 in iter) {
+    self::Foo* x = #t3 as{TypeError,ForDynamic} self::Foo*;
+    self::Foo* y = x;
+  }
+  dynamic iter2 = list;
+  for (final dynamic #t4 in iter2 as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+    self::Foo* x = #t4 as{TypeError,ForDynamic} self::Foo*;
+    self::Foo* y = x;
+  }
+  core::Map<core::String*, self::Foo*>* map = <core::String*, self::Foo*>{};
+  for (dynamic x in invalid-expression "pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart:60:70: Error: The type 'Map<String, Foo>' used in the 'for' loop must implement 'Iterable<dynamic>'.
+ - 'Map' is from 'dart:core'.
+ - 'Foo' is from 'pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop.dart'.
+ - 'Iterable' is from 'dart:core'.
+  for (var /*@ type=dynamic */ x in /*error:FOR_IN_OF_INVALID_TYPE*/ map) {
+                                                                     ^" in map as{TypeError} core::Iterable<dynamic>*) {
+    core::String* y = x as{TypeError,ForDynamic} core::String*;
+  }
+  for (core::String* x in map.{core::Map::keys}{core::Iterable<core::String*>*}) {
+    core::String* y = x;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart.weak.modular.expect
new file mode 100644
index 0000000..c16146f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart.weak.modular.expect
@@ -0,0 +1,198 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart:17:44: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       int x = /*error:INVALID_ASSIGNMENT*/ i;
+//                                            ^
+//
+// pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart:25:44: Error: A value of type 'T' can't be assigned to a variable of type 'int'.
+//       int x = /*error:INVALID_ASSIGNMENT*/ i;
+//                                            ^
+//
+// pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart:38:45: Error: A value of type 'Foo' can't be assigned to a variable of type 'String'.
+//  - 'Foo' is from 'pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart'.
+//     String y = /*error:INVALID_ASSIGNMENT*/ x;
+//                                             ^
+//
+// pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart:45:21: Error: A value of type 'Foo' can't be assigned to a variable of type 'String'.
+//  - 'Foo' is from 'pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart'.
+// Try changing the type of the variable.
+//   await for (String x in /*error:FOR_IN_OF_INVALID_ELEMENT_TYPE*/ myStream) {
+//                     ^
+//
+// pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart:66:76: Error: The type 'Map<String, Foo>' used in the 'for' loop must implement 'Stream<dynamic>'.
+//  - 'Map' is from 'dart:core'.
+//  - 'Foo' is from 'pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart'.
+//  - 'Stream' is from 'dart:async'.
+//   await for (var /*@ type=dynamic */ x in /*error:FOR_IN_OF_INVALID_TYPE*/ map) {
+//                                                                            ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class Foo extends core::Object {
+  field core::int* bar = 42;
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar<T extends asy::Stream<core::String*>*> extends core::Object {
+  synthetic constructor •() → self::Bar<self::Bar::T*>*
+    : super core::Object::•()
+    ;
+  method foo(covariant-by-class self::Bar::T* t) → dynamic async {
+    await for (core::String* i in t) {
+      core::int* x = invalid-expression "pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart:17:44: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      int x = /*error:INVALID_ASSIGNMENT*/ i;
+                                           ^" in i as{TypeError} core::int*;
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Baz<T extends core::Object* = dynamic, E extends asy::Stream<self::Baz::T*>* = asy::Stream<dynamic>*, S extends self::Baz::E* = asy::Stream<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::Baz<self::Baz::T*, self::Baz::E*, self::Baz::S*>*
+    : super core::Object::•()
+    ;
+  method foo(covariant-by-class self::Baz::S* t) → dynamic async {
+    await for (self::Baz::T* i in t) {
+      core::int* x = invalid-expression "pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart:25:44: Error: A value of type 'T' can't be assigned to a variable of type 'int'.
+      int x = /*error:INVALID_ASSIGNMENT*/ i;
+                                           ^" in i as{TypeError} core::int*;
+      self::Baz::T* y = i;
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class MyStream<T extends core::Object* = dynamic> extends asy::Stream<self::MyStream::T*> {
+  static factory •<T extends core::Object* = dynamic>() → self::MyStream<self::MyStream::•::T*>*
+    return null;
+  abstract member-signature get isBroadcast() → core::bool*; -> asy::Stream::isBroadcast
+  abstract member-signature method asBroadcastStream({(asy::StreamSubscription<self::MyStream::T*>*) →* void onListen = #C1, (asy::StreamSubscription<self::MyStream::T*>*) →* void onCancel = #C1}) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::asBroadcastStream
+  abstract member-signature method where((self::MyStream::T*) →* core::bool* test) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::where
+  abstract member-signature method map<S extends core::Object* = dynamic>((self::MyStream::T*) →* self::MyStream::map::S* convert) → asy::Stream<self::MyStream::map::S*>*; -> asy::Stream::map
+  abstract member-signature method asyncMap<E extends core::Object* = dynamic>((self::MyStream::T*) →* FutureOr<self::MyStream::asyncMap::E*>* convert) → asy::Stream<self::MyStream::asyncMap::E*>*; -> asy::Stream::asyncMap
+  abstract member-signature method asyncExpand<E extends core::Object* = dynamic>((self::MyStream::T*) →* asy::Stream<self::MyStream::asyncExpand::E*>* convert) → asy::Stream<self::MyStream::asyncExpand::E*>*; -> asy::Stream::asyncExpand
+  abstract member-signature method handleError(core::Function* onError, {(dynamic) →* core::bool* test = #C1}) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::handleError
+  abstract member-signature method expand<S extends core::Object* = dynamic>((self::MyStream::T*) →* core::Iterable<self::MyStream::expand::S*>* convert) → asy::Stream<self::MyStream::expand::S*>*; -> asy::Stream::expand
+  abstract member-signature method pipe(covariant-by-class asy::StreamConsumer<self::MyStream::T*>* streamConsumer) → asy::Future<dynamic>*; -> asy::Stream::pipe
+  abstract member-signature method transform<S extends core::Object* = dynamic>(covariant-by-class asy::StreamTransformer<self::MyStream::T*, self::MyStream::transform::S*>* streamTransformer) → asy::Stream<self::MyStream::transform::S*>*; -> asy::Stream::transform
+  abstract member-signature method reduce(covariant-by-class (self::MyStream::T*, self::MyStream::T*) →* self::MyStream::T* combine) → asy::Future<self::MyStream::T*>*; -> asy::Stream::reduce
+  abstract member-signature method fold<S extends core::Object* = dynamic>(self::MyStream::fold::S* initialValue, (self::MyStream::fold::S*, self::MyStream::T*) →* self::MyStream::fold::S* combine) → asy::Future<self::MyStream::fold::S*>*; -> asy::Stream::fold
+  abstract member-signature method join([core::String* separator = #C2]) → asy::Future<core::String*>*; -> asy::Stream::join
+  abstract member-signature method contains(core::Object* needle) → asy::Future<core::bool*>*; -> asy::Stream::contains
+  abstract member-signature method forEach((self::MyStream::T*) →* void action) → asy::Future<dynamic>*; -> asy::Stream::forEach
+  abstract member-signature method every((self::MyStream::T*) →* core::bool* test) → asy::Future<core::bool*>*; -> asy::Stream::every
+  abstract member-signature method any((self::MyStream::T*) →* core::bool* test) → asy::Future<core::bool*>*; -> asy::Stream::any
+  abstract member-signature get length() → asy::Future<core::int*>*; -> asy::Stream::length
+  abstract member-signature get isEmpty() → asy::Future<core::bool*>*; -> asy::Stream::isEmpty
+  abstract member-signature method cast<R extends core::Object* = dynamic>() → asy::Stream<self::MyStream::cast::R*>*; -> asy::Stream::cast
+  abstract member-signature method toList() → asy::Future<core::List<self::MyStream::T*>*>*; -> asy::Stream::toList
+  abstract member-signature method toSet() → asy::Future<core::Set<self::MyStream::T*>*>*; -> asy::Stream::toSet
+  abstract member-signature method drain<E extends core::Object* = dynamic>([self::MyStream::drain::E* futureValue = #C1]) → asy::Future<self::MyStream::drain::E*>*; -> asy::Stream::drain
+  abstract member-signature method take(core::int* count) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::take
+  abstract member-signature method takeWhile((self::MyStream::T*) →* core::bool* test) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::takeWhile
+  abstract member-signature method skip(core::int* count) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::skip
+  abstract member-signature method skipWhile((self::MyStream::T*) →* core::bool* test) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::skipWhile
+  abstract member-signature method distinct([(self::MyStream::T*, self::MyStream::T*) →* core::bool* equals = #C1]) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::distinct
+  abstract member-signature get first() → asy::Future<self::MyStream::T*>*; -> asy::Stream::first
+  abstract member-signature get last() → asy::Future<self::MyStream::T*>*; -> asy::Stream::last
+  abstract member-signature get single() → asy::Future<self::MyStream::T*>*; -> asy::Stream::single
+  abstract member-signature method firstWhere((self::MyStream::T*) →* core::bool* test, {covariant-by-class () →* self::MyStream::T* orElse = #C1}) → asy::Future<self::MyStream::T*>*; -> asy::Stream::firstWhere
+  abstract member-signature method lastWhere((self::MyStream::T*) →* core::bool* test, {covariant-by-class () →* self::MyStream::T* orElse = #C1}) → asy::Future<self::MyStream::T*>*; -> asy::Stream::lastWhere
+  abstract member-signature method singleWhere((self::MyStream::T*) →* core::bool* test, {covariant-by-class () →* self::MyStream::T* orElse = #C1}) → asy::Future<self::MyStream::T*>*; -> asy::Stream::singleWhere
+  abstract member-signature method elementAt(core::int* index) → asy::Future<self::MyStream::T*>*; -> asy::Stream::elementAt
+  abstract member-signature method timeout(core::Duration* timeLimit, {(asy::EventSink<self::MyStream::T*>*) →* void onTimeout = #C1}) → asy::Stream<self::MyStream::T*>*; -> asy::Stream::timeout
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature method listen((self::MyStream::T*) →* void onData, {core::Function* onError = #C1, () →* void onDone = #C1, core::bool* cancelOnError = #C1}) → asy::StreamSubscription<self::MyStream::T*>*; -> asy::Stream::listen
+}
+static method test() → dynamic async {
+  self::MyStream<self::Foo*>* myStream = self::MyStream::•<self::Foo*>();
+  await for (self::Foo* x in myStream) {
+    core::String* y = invalid-expression "pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart:38:45: Error: A value of type 'Foo' can't be assigned to a variable of type 'String'.
+ - 'Foo' is from 'pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart'.
+    String y = /*error:INVALID_ASSIGNMENT*/ x;
+                                            ^" in x as{TypeError} core::String*;
+  }
+  await for (dynamic x in myStream) {
+    core::String* y = x as{TypeError,ForDynamic} core::String*;
+  }
+  await for (final self::Foo* #t1 in myStream) {
+    core::String* x = invalid-expression "pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart:45:21: Error: A value of type 'Foo' can't be assigned to a variable of type 'String'.
+ - 'Foo' is from 'pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart'.
+Try changing the type of the variable.
+  await for (String x in /*error:FOR_IN_OF_INVALID_ELEMENT_TYPE*/ myStream) {
+                    ^" in #t1 as{TypeError} core::String*;
+    core::String* y = x;
+  }
+  dynamic z;
+  await for (final self::Foo* #t2 in myStream) {
+    z = #t2;
+    core::String* y = z as{TypeError,ForDynamic} core::String*;
+  }
+  asy::Stream<dynamic>* stream = myStream;
+  await for (final dynamic #t3 in stream) {
+    self::Foo* x = #t3 as{TypeError,ForDynamic} self::Foo*;
+    self::Foo* y = x;
+  }
+  dynamic stream2 = myStream;
+  await for (final dynamic #t4 in stream2 as{TypeError,ForDynamic} asy::Stream<dynamic>*) {
+    self::Foo* x = #t4 as{TypeError,ForDynamic} self::Foo*;
+    self::Foo* y = x;
+  }
+  core::Map<core::String*, self::Foo*>* map = <core::String*, self::Foo*>{};
+  await for (dynamic x in invalid-expression "pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart:66:76: Error: The type 'Map<String, Foo>' used in the 'for' loop must implement 'Stream<dynamic>'.
+ - 'Map' is from 'dart:core'.
+ - 'Foo' is from 'pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_each_loop_async.dart'.
+ - 'Stream' is from 'dart:async'.
+  await for (var /*@ type=dynamic */ x in /*error:FOR_IN_OF_INVALID_TYPE*/ map) {
+                                                                           ^" in map as{TypeError} asy::Stream<dynamic>*) {
+    core::String* y = x as{TypeError,ForDynamic} core::String*;
+  }
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = ""
+}
diff --git a/pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_loop_with_inference.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_loop_with_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..22c972f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_types_on_loop_indices_for_loop_with_inference.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test() → dynamic {
+  for (core::int* i = 0; i.{core::num::<}(10){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+    core::int* j = i.{core::num::+}(1){(core::num*) →* core::int*};
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_use_of_void_local.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_use_of_void_local.dart.weak.modular.expect
new file mode 100644
index 0000000..f8773b2
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_use_of_void_local.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library test;
+import self as self;
+
+static method f() → void {}
+static method g() → void {
+  void x = self::f();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/infer_variable_void.dart.weak.modular.expect b/pkg/front_end/testcases/inference/infer_variable_void.dart.weak.modular.expect
new file mode 100644
index 0000000..3bfd2e6
--- /dev/null
+++ b/pkg/front_end/testcases/inference/infer_variable_void.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library test;
+import self as self;
+
+static field void x = self::f();
+static method f() → void {}
+static method main() → dynamic {
+  self::x;
+}
diff --git a/pkg/front_end/testcases/inference/inferred_initializing_formal_checks_default_value.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_initializing_formal_checks_default_value.dart.weak.modular.expect
new file mode 100644
index 0000000..524ef39
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_initializing_formal_checks_default_value.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/inferred_initializing_formal_checks_default_value.dart:10:46: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   Foo([this.x = /*error:INVALID_ASSIGNMENT*/ "1"]);
+//                                              ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  field core::int* x = 1;
+  constructor •([core::int* x = invalid-expression "pkg/front_end/testcases/inference/inferred_initializing_formal_checks_default_value.dart:10:46: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  Foo([this.x = /*error:INVALID_ASSIGNMENT*/ \"1\"]);
+                                             ^"]) → self::Foo*
+    : self::Foo::x = x, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/inferred_initializing_formal_checks_default_value.dart.weak.outline.expect b/pkg/front_end/testcases/inference/inferred_initializing_formal_checks_default_value.dart.weak.outline.expect
index 0bc9761..c617c3d 100644
--- a/pkg/front_end/testcases/inference/inferred_initializing_formal_checks_default_value.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/inference/inferred_initializing_formal_checks_default_value.dart.weak.outline.expect
@@ -1,10 +1,19 @@
 library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/inferred_initializing_formal_checks_default_value.dart:10:46: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   Foo([this.x = /*error:INVALID_ASSIGNMENT*/ "1"]);
+//                                              ^
+//
 import self as self;
 import "dart:core" as core;
 
 class Foo extends core::Object {
   field core::int* x;
-  constructor •([core::int* x]) → self::Foo*
+  constructor •([core::int* x = invalid-expression "pkg/front_end/testcases/inference/inferred_initializing_formal_checks_default_value.dart:10:46: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  Foo([this.x = /*error:INVALID_ASSIGNMENT*/ \"1\"]);
+                                             ^" in "1" as{TypeError} core::int*]) → self::Foo*
     ;
   abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
   abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
diff --git a/pkg/front_end/testcases/inference/inferred_nonstatic_field_depends_on_static_field_complex.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_nonstatic_field_depends_on_static_field_complex.dart.weak.modular.expect
new file mode 100644
index 0000000..24a6a4b
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_nonstatic_field_depends_on_static_field_complex.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::String* x = "x";
+  field core::Map<core::String*, core::Map<core::String*, core::String*>*>* y = <core::String*, core::Map<core::String*, core::String*>*>{"a": <core::String*, core::String*>{"b": "c"}, "d": <core::String*, core::String*>{"e": self::C::x}};
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/inferred_nonstatic_field_depends_on_top_level_var_simple.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_nonstatic_field_depends_on_top_level_var_simple.dart.weak.modular.expect
new file mode 100644
index 0000000..3b47743
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_nonstatic_field_depends_on_top_level_var_simple.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field core::String* y = self::x;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::String* x = "x";
+static method main() → dynamic {
+  self::x;
+}
diff --git a/pkg/front_end/testcases/inference/inferred_type_block_closure_no_args_no_return.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_block_closure_no_args_no_return.dart.weak.modular.expect
new file mode 100644
index 0000000..8ee4d33
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_block_closure_no_args_no_return.dart.weak.modular.expect
@@ -0,0 +1,6 @@
+library test;
+import self as self;
+
+static method main() → dynamic {
+  () →* Null f = () → Null {};
+}
diff --git a/pkg/front_end/testcases/inference/inferred_type_block_closure_no_args_no_return_void_context.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_block_closure_no_args_no_return_void_context.dart.weak.modular.expect
new file mode 100644
index 0000000..21efe4c
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_block_closure_no_args_no_return_void_context.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  constructor •(() →* void func) → self::C*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C* c = new self::C::•(() → Null {});
+}
diff --git a/pkg/front_end/testcases/inference/inferred_type_cascade.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_cascade.dart.weak.modular.expect
new file mode 100644
index 0000000..e5b98d2
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_cascade.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* a = null;
+  field core::List<core::int*>* b = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method m() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::A* v = let final self::A* #t1 = new self::A::•() in block {
+  #t1.{self::A::a} = 1;
+  #t1.{self::A::b}{core::List<core::int*>*}.{core::List::add}(2){(core::int*) →* void};
+  #t1.{self::A::m}(){() →* void};
+} =>#t1;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/inferred_type_custom_binary_op.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_custom_binary_op.dart.weak.modular.expect
new file mode 100644
index 0000000..83b4e3b
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_custom_binary_op.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  operator *(self::C* other) → core::bool*
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C* c = new self::C::•();
+static field core::bool* x = self::c.{self::C::*}(self::c){(self::C*) →* core::bool*};
+static method main() → dynamic {
+  self::c;
+  self::x;
+}
diff --git a/pkg/front_end/testcases/inference/inferred_type_custom_binary_op_via_interface.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_custom_binary_op_via_interface.dart.weak.modular.expect
new file mode 100644
index 0000000..6764bc5
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_custom_binary_op_via_interface.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  operator *(self::C* other) → core::bool*
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object implements self::I {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C* c;
+static field core::bool* x = self::c.{self::I::*}(self::c){(self::C*) →* core::bool*};
+static method main() → dynamic {
+  self::c;
+}
diff --git a/pkg/front_end/testcases/inference/inferred_type_custom_index_op.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_custom_index_op.dart.weak.modular.expect
new file mode 100644
index 0000000..250adf8
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_custom_index_op.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  operator [](core::int* index) → core::bool*
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C* c = new self::C::•();
+  core::bool* x = c.{self::C::[]}(0){(core::int*) →* core::bool*};
+}
diff --git a/pkg/front_end/testcases/inference/inferred_type_custom_index_op_via_interface.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_custom_index_op_via_interface.dart.weak.modular.expect
new file mode 100644
index 0000000..007c0cd
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_custom_index_op_via_interface.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  operator [](core::int* index) → core::bool*
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object implements self::I {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f() → dynamic {
+  self::C* c;
+  core::bool* x = c.{self::I::[]}(0){(core::int*) →* core::bool*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/inferred_type_custom_unary_op.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_custom_unary_op.dart.weak.modular.expect
new file mode 100644
index 0000000..d0c4a3c
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_custom_unary_op.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  operator unary-() → core::bool*
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C* c = new self::C::•();
+static field core::bool* x = self::c.{self::C::unary-}(){() →* core::bool*};
+static method main() → dynamic {
+  self::c;
+  self::x;
+}
diff --git a/pkg/front_end/testcases/inference/inferred_type_custom_unary_op_via_interface.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_custom_unary_op_via_interface.dart.weak.modular.expect
new file mode 100644
index 0000000..443ba4b
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_custom_unary_op_via_interface.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  operator unary-() → core::bool*
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object implements self::I {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C* c;
+static field core::bool* x = self::c.{self::I::unary-}(){() →* core::bool*};
+static method main() → dynamic {
+  self::c;
+}
diff --git a/pkg/front_end/testcases/inference/inferred_type_extract_method_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_extract_method_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..909f982
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_extract_method_tear_off.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method g() → core::bool*
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field () →* core::bool* x = self::f().{self::C::g}{() →* core::bool*};
+static method f() → self::C*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/inferred_type_extract_method_tear_off_via_interface.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_extract_method_tear_off_via_interface.dart.weak.modular.expect
new file mode 100644
index 0000000..a162c11
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_extract_method_tear_off_via_interface.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  method g() → core::bool*
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object implements self::I {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field () →* core::bool* x = self::f().{self::I::g}{() →* core::bool*};
+static method f() → self::C*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/inferred_type_from_top_level_executable_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_from_top_level_executable_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..6eef7cc
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_from_top_level_executable_tear_off.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field (core::Object*) →* void v = #C1;
+static method main() → dynamic {
+  self::v;
+}
+
+constants  {
+  #C1 = static-tearoff core::print
+}
diff --git a/pkg/front_end/testcases/inference/inferred_type_invoke_method.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_invoke_method.dart.weak.modular.expect
new file mode 100644
index 0000000..429fa8a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_invoke_method.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method g() → core::bool*
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::bool* x = self::f().{self::C::g}(){() →* core::bool*};
+static method f() → self::C*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/inferred_type_invoke_method_via_interface.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_invoke_method_via_interface.dart.weak.modular.expect
new file mode 100644
index 0000000..c694d88
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_invoke_method_via_interface.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  method g() → core::bool*
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object implements self::I {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::bool* x = self::f().{self::I::g}(){() →* core::bool*};
+static method f() → self::C*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/inferred_type_is_enum.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_is_enum.dart.weak.modular.expect
new file mode 100644
index 0000000..5f1e09a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_is_enum.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class E extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::E*>* values = #C4;
+  static const field self::E* v1 = #C3;
+  const constructor •(core::int* index, core::String* name) → self::E*
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String*
+    return "E.${this.{core::_Enum::_name}{core::String}}";
+  abstract member-signature get index() → core::int*; -> core::_Enum::index
+  abstract member-signature get _name() → core::String*; -> core::_Enum::_name
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static final field self::E* x = #C3;
+static method main() → dynamic {
+  self::x;
+}
+
+constants  {
+  #C1 = 0
+  #C2 = "v1"
+  #C3 = self::E {index:#C1, _name:#C2}
+  #C4 = <self::E*>[#C3]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///inferred_type_is_enum.dart:
+- E. (from org-dartlang-testcase:///inferred_type_is_enum.dart:8:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:76:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/inference/inferred_type_is_enum_values.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_is_enum_values.dart.weak.modular.expect
new file mode 100644
index 0000000..624054f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_is_enum_values.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class E extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::E*>* values = #C4;
+  static const field self::E* v1 = #C3;
+  const constructor •(core::int* index, core::String* name) → self::E*
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String*
+    return "E.${this.{core::_Enum::_name}{core::String}}";
+  abstract member-signature get index() → core::int*; -> core::_Enum::index
+  abstract member-signature get _name() → core::String*; -> core::_Enum::_name
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static final field core::List<self::E*>* x = #C4;
+static method main() → dynamic {
+  self::x;
+}
+
+constants  {
+  #C1 = 0
+  #C2 = "v1"
+  #C3 = self::E {index:#C1, _name:#C2}
+  #C4 = <self::E*>[#C3]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///inferred_type_is_enum_values.dart:
+- E. (from org-dartlang-testcase:///inferred_type_is_enum_values.dart:8:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:76:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/inference/inferred_type_is_typedef.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_is_typedef.dart.weak.modular.expect
new file mode 100644
index 0000000..2f74b63
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_is_typedef.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F = () →* void;
+static final field core::Map<core::String*, () →* void>* x = <core::String*, () →* void>{};
+static method main() → dynamic {
+  self::x;
+}
diff --git a/pkg/front_end/testcases/inference/inferred_type_is_typedef_parameterized.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_is_typedef_parameterized.dart.weak.modular.expect
new file mode 100644
index 0000000..24aba57
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_is_typedef_parameterized.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<T extends core::Object* = dynamic> = () →* T*;
+static final field core::Map<core::String*, () →* core::int*>* x = <core::String*, () →* core::int*>{};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/inferred_type_uses_synthetic_function_type.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_uses_synthetic_function_type.dart.weak.modular.expect
new file mode 100644
index 0000000..21d3b06
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_uses_synthetic_function_type.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<() →* core::Object*>* v = <() →* core::Object*>[#C1, #C2];
+static method f() → core::int*
+  return null;
+static method g() → core::String*
+  return null;
+static method main() → dynamic {
+  self::v;
+}
+
+constants  {
+  #C1 = static-tearoff self::f
+  #C2 = static-tearoff self::g
+}
diff --git a/pkg/front_end/testcases/inference/inferred_type_uses_synthetic_function_type_function_typed_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_uses_synthetic_function_type_function_typed_param.dart.weak.modular.expect
new file mode 100644
index 0000000..9be942f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_uses_synthetic_function_type_function_typed_param.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<((core::String*) →* core::int*) →* core::Object*>* v = <((core::String*) →* core::int*) →* core::Object*>[#C1, #C2];
+static method f((core::String*) →* core::int* x) → core::int*
+  return null;
+static method g((core::String*) →* core::int* x) → core::String*
+  return null;
+static method main() → dynamic {
+  self::v;
+}
+
+constants  {
+  #C1 = static-tearoff self::f
+  #C2 = static-tearoff self::g
+}
diff --git a/pkg/front_end/testcases/inference/inferred_type_uses_synthetic_function_type_named_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_uses_synthetic_function_type_named_param.dart.weak.modular.expect
new file mode 100644
index 0000000..0b7d047
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_uses_synthetic_function_type_named_param.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<({x: core::int*}) →* core::Object*>* v = <({x: core::int*}) →* core::Object*>[#C1, #C2];
+static method f({core::int* x = #C3}) → core::int*
+  return null;
+static method g({core::int* x = #C3}) → core::String*
+  return null;
+static method main() → dynamic {
+  self::v;
+}
+
+constants  {
+  #C1 = static-tearoff self::f
+  #C2 = static-tearoff self::g
+  #C3 = null
+}
diff --git a/pkg/front_end/testcases/inference/inferred_type_uses_synthetic_function_type_positional_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_uses_synthetic_function_type_positional_param.dart.weak.modular.expect
new file mode 100644
index 0000000..704ff597
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_uses_synthetic_function_type_positional_param.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<([core::int*]) →* core::Object*>* v = <([core::int*]) →* core::Object*>[#C1, #C2];
+static method f([core::int* x = #C3]) → core::int*
+  return null;
+static method g([core::int* x = #C3]) → core::String*
+  return null;
+static method main() → dynamic {
+  self::v;
+}
+
+constants  {
+  #C1 = static-tearoff self::f
+  #C2 = static-tearoff self::g
+  #C3 = null
+}
diff --git a/pkg/front_end/testcases/inference/inferred_type_uses_synthetic_function_type_required_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_uses_synthetic_function_type_required_param.dart.weak.modular.expect
new file mode 100644
index 0000000..b495253
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_uses_synthetic_function_type_required_param.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<(core::int*) →* core::Object*>* v = <(core::int*) →* core::Object*>[#C1, #C2];
+static method f(core::int* x) → core::int*
+  return null;
+static method g(core::int* x) → core::String*
+  return null;
+static method main() → dynamic {
+  self::v;
+}
+
+constants  {
+  #C1 = static-tearoff self::f
+  #C2 = static-tearoff self::g
+}
diff --git a/pkg/front_end/testcases/inference/inferred_type_via_closure_multiple_levels_of_nesting.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_via_closure_multiple_levels_of_nesting.dart.weak.modular.expect
new file mode 100644
index 0000000..7c6c26d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_via_closure_multiple_levels_of_nesting.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static final field (core::bool*) →* (core::int*) →* core::Map<core::int*, core::bool*>* f = (core::bool* b) → (core::int*) →* core::Map<core::int*, core::bool*>* => (core::int* i) → core::Map<core::int*, core::bool*>* => <core::int*, core::bool*>{i: b};
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/inferred_type_via_closure_type_depends_on_args.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_via_closure_type_depends_on_args.dart.weak.modular.expect
new file mode 100644
index 0000000..edd69ee
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_via_closure_type_depends_on_args.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static final field (core::bool*) →* core::bool* f = (core::bool* b) → core::bool* => b;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/inferred_type_via_closure_type_independent_of_args_field.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_via_closure_type_independent_of_args_field.dart.weak.modular.expect
new file mode 100644
index 0000000..06af2b3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_via_closure_type_independent_of_args_field.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static final field (core::bool*) →* core::int* f = (core::bool* b) → core::int* => 1;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/inferred_type_via_closure_type_independent_of_args_top_level.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inferred_type_via_closure_type_independent_of_args_top_level.dart.weak.modular.expect
new file mode 100644
index 0000000..ac18ccc
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inferred_type_via_closure_type_independent_of_args_top_level.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static final field (core::bool*) →* core::int* f = (core::bool* b) → core::int* => 1;
+static method main() → dynamic {
+  self::f;
+}
diff --git a/pkg/front_end/testcases/inference/inheritance_does_not_imply_circularity.dart.weak.modular.expect b/pkg/front_end/testcases/inference/inheritance_does_not_imply_circularity.dart.weak.modular.expect
new file mode 100644
index 0000000..7b33a23
--- /dev/null
+++ b/pkg/front_end/testcases/inference/inheritance_does_not_imply_circularity.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class I1 extends core::Object {
+  final field core::int* x = self::y;
+  synthetic constructor •() → self::I1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I2 extends core::Object {
+  synthetic constructor •() → self::I2*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::num*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object implements self::I1, self::I2 {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  get x() → core::int*
+    return 0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* y = new self::C::•().{self::C::x}{core::int*};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/instance_creation_downwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/instance_creation_downwards.dart.weak.modular.expect
new file mode 100644
index 0000000..1e592bc2
--- /dev/null
+++ b/pkg/front_end/testcases/inference/instance_creation_downwards.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(self::B<core::List<self::A::T*>*>* b) → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::A<dynamic>* x = new self::A::•<dynamic>(new self::B::•<core::List<dynamic>*>());
+}
diff --git a/pkg/front_end/testcases/inference/instantiate_tearoff.dart.weak.modular.expect b/pkg/front_end/testcases/inference/instantiate_tearoff.dart.weak.modular.expect
new file mode 100644
index 0000000..f272f74
--- /dev/null
+++ b/pkg/front_end/testcases/inference/instantiate_tearoff.dart.weak.modular.expect
@@ -0,0 +1,51 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f<T extends core::Object* = dynamic>(self::C::f::T* x) → self::C::f::T*
+    return x;
+  static method g<T extends core::Object* = dynamic>(self::C::g::T* x) → self::C::g::T*
+    return x;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method test() → void {
+    (core::int*) →* core::int* func;
+    func = super.{self::C::f}<core::int*>;
+  }
+}
+static method f<T extends core::Object* = dynamic>(self::f::T* x) → self::f::T*
+  return x;
+static method test() → void {
+  function h<T extends core::Object* = dynamic>(T* x) → T*
+    return x;
+  (core::int*) →* core::int* func;
+  func = #C2;
+  func = new self::C::•().{self::C::f}{<T extends core::Object* = dynamic>(T*) →* T*}<core::int*>;
+  func = #C4;
+  func = h<core::int*>;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::f
+  #C2 = instantiation #C1 <core::int*>
+  #C3 = static-tearoff self::C::g
+  #C4 = instantiation #C3 <core::int*>
+}
diff --git a/pkg/front_end/testcases/inference/instantiate_tearoff_after_contravariance_check.dart.weak.modular.expect b/pkg/front_end/testcases/inference/instantiate_tearoff_after_contravariance_check.dart.weak.modular.expect
new file mode 100644
index 0000000..86594e9
--- /dev/null
+++ b/pkg/front_end/testcases/inference/instantiate_tearoff_after_contravariance_check.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method f<U extends core::Object* = dynamic>(self::C::f::U* x) → (self::C::T*) →* void
+    return (self::C::T* y) → Null {};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test(self::C<core::String*>* c) → void {
+  (core::int*) →* (core::String*) →* void tearoff = (c.{self::C::f}{<U extends core::Object* = dynamic>(U*) →* (core::String*) →* void} as{TypeError,CovarianceCheck} <U extends core::Object* = dynamic>(U*) →* (core::String*) →* void)<core::int*>;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/instantiate_tearoff_of_call.dart.weak.modular.expect b/pkg/front_end/testcases/inference/instantiate_tearoff_of_call.dart.weak.modular.expect
new file mode 100644
index 0000000..2e086bf
--- /dev/null
+++ b/pkg/front_end/testcases/inference/instantiate_tearoff_of_call.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/instantiate_tearoff_of_call.dart:10:12: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'int Function(int)'.
+//   func = f.call;
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test(<T extends core::Object* = dynamic>(T*) →* T* f) → void {
+  (core::int*) →* core::int* func;
+  func = invalid-expression "pkg/front_end/testcases/inference/instantiate_tearoff_of_call.dart:10:12: Error: A value of type 'T Function<T>(T)' can't be assigned to a variable of type 'int Function(int)'.
+  func = f.call;
+           ^" in f.call as{TypeError} (core::int*) →* core::int*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/instantiate_to_bounds_generic2_has_bound_defined_after.dart.weak.modular.expect b/pkg/front_end/testcases/inference/instantiate_to_bounds_generic2_has_bound_defined_after.dart.weak.modular.expect
new file mode 100644
index 0000000..0fb60dc
--- /dev/null
+++ b/pkg/front_end/testcases/inference/instantiate_to_bounds_generic2_has_bound_defined_after.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B<T extends self::A<core::int*>*> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A<T extends core::int*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::B<self::A<core::int*>*>* v = null;
+static method main() → dynamic {
+  self::v;
+}
diff --git a/pkg/front_end/testcases/inference/instantiate_to_bounds_generic2_has_bound_defined_before.dart.weak.modular.expect b/pkg/front_end/testcases/inference/instantiate_to_bounds_generic2_has_bound_defined_before.dart.weak.modular.expect
new file mode 100644
index 0000000..0612d0f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/instantiate_to_bounds_generic2_has_bound_defined_before.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::int*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends self::A<core::int*>*> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::B<self::A<core::int*>*>* v = null;
+static method main() → dynamic {
+  self::v;
+}
diff --git a/pkg/front_end/testcases/inference/instantiate_to_bounds_generic2_no_bound.dart.weak.modular.expect b/pkg/front_end/testcases/inference/instantiate_to_bounds_generic2_no_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..731ae28
--- /dev/null
+++ b/pkg/front_end/testcases/inference/instantiate_to_bounds_generic2_no_bound.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends self::A<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::B<self::A<dynamic>*>* v = null;
+static method main() → dynamic {
+  self::v;
+}
diff --git a/pkg/front_end/testcases/inference/instantiate_to_bounds_generic_has_bound_defined_after.dart.weak.modular.expect b/pkg/front_end/testcases/inference/instantiate_to_bounds_generic_has_bound_defined_after.dart.weak.modular.expect
new file mode 100644
index 0000000..09072c4
--- /dev/null
+++ b/pkg/front_end/testcases/inference/instantiate_to_bounds_generic_has_bound_defined_after.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::int*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::A<core::int*>* v = null;
+static method main() → dynamic {
+  self::v;
+}
diff --git a/pkg/front_end/testcases/inference/instantiate_to_bounds_generic_has_bound_defined_before.dart.weak.modular.expect b/pkg/front_end/testcases/inference/instantiate_to_bounds_generic_has_bound_defined_before.dart.weak.modular.expect
new file mode 100644
index 0000000..09072c4
--- /dev/null
+++ b/pkg/front_end/testcases/inference/instantiate_to_bounds_generic_has_bound_defined_before.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::int*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::A<core::int*>* v = null;
+static method main() → dynamic {
+  self::v;
+}
diff --git a/pkg/front_end/testcases/inference/instantiate_to_bounds_invoke_constructor_no_bound.dart.weak.modular.expect b/pkg/front_end/testcases/inference/instantiate_to_bounds_invoke_constructor_no_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..05cb019
--- /dev/null
+++ b/pkg/front_end/testcases/inference/instantiate_to_bounds_invoke_constructor_no_bound.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C<dynamic>* v = new self::C::•<dynamic>();
+}
diff --git a/pkg/front_end/testcases/inference/instantiate_to_bounds_invoke_constructor_type_args_exact.dart.weak.modular.expect b/pkg/front_end/testcases/inference/instantiate_to_bounds_invoke_constructor_type_args_exact.dart.weak.modular.expect
new file mode 100644
index 0000000..1fb9971
--- /dev/null
+++ b/pkg/front_end/testcases/inference/instantiate_to_bounds_invoke_constructor_type_args_exact.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::num*> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C<core::int*>* x = new self::C::•<core::int*>();
+static method main() → dynamic {
+  self::x;
+}
diff --git a/pkg/front_end/testcases/inference/instantiate_to_bounds_not_generic.dart.weak.modular.expect b/pkg/front_end/testcases/inference/instantiate_to_bounds_not_generic.dart.weak.modular.expect
new file mode 100644
index 0000000..6bd9194
--- /dev/null
+++ b/pkg/front_end/testcases/inference/instantiate_to_bounds_not_generic.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends self::A*> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::B<self::A*>* v = null;
+static method main() → dynamic {
+  self::v;
+}
diff --git a/pkg/front_end/testcases/inference/int_upwards_local.dart.weak.modular.expect b/pkg/front_end/testcases/inference/int_upwards_local.dart.weak.modular.expect
new file mode 100644
index 0000000..bdd406c
--- /dev/null
+++ b/pkg/front_end/testcases/inference/int_upwards_local.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::int* x = 1;
+}
diff --git a/pkg/front_end/testcases/inference/issue41199.dart.weak.modular.expect b/pkg/front_end/testcases/inference/issue41199.dart.weak.modular.expect
new file mode 100644
index 0000000..6d7392d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/issue41199.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method foo<X extends core::Object* = dynamic>(<Y extends core::Object* = dynamic>() →* core::Map<self::foo::X*, Y*>* f) → dynamic
+  return null;
+static method baz() → dynamic
+  return self::foo<dynamic>(<Z extends core::Object* = dynamic>() → core::Map<dynamic, Z*>* => <dynamic, Z*>{});
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/lambda_does_not_have_propagated_type_hint.dart.weak.modular.expect b/pkg/front_end/testcases/inference/lambda_does_not_have_propagated_type_hint.dart.weak.modular.expect
new file mode 100644
index 0000000..9cfc708
--- /dev/null
+++ b/pkg/front_end/testcases/inference/lambda_does_not_have_propagated_type_hint.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method getListOfString() → core::List<core::String*>*
+  return #C1;
+static method foo() → void {
+  core::List<dynamic>* myList = self::getListOfString();
+  myList.{core::Iterable::map}<core::int*>((dynamic type) → core::int* => 42){((dynamic) →* core::int*) →* core::Iterable<core::int*>*};
+}
+static method bar() → void {
+  dynamic list;
+  try {
+    list = <core::String*>[];
+  }
+  on dynamic catch(final dynamic _) {
+    return;
+  }
+  list{dynamic}.map((dynamic value) → core::String* => "${value}");
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = <core::String*>[]
+}
diff --git a/pkg/front_end/testcases/inference/lambda_return_type.dart.weak.modular.expect b/pkg/front_end/testcases/inference/lambda_return_type.dart.weak.modular.expect
new file mode 100644
index 0000000..c4026b5
--- /dev/null
+++ b/pkg/front_end/testcases/inference/lambda_return_type.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef FunctionReturningNum = () →* core::num*;
+static method test() → dynamic {
+  core::int* i = 1;
+  core::Object* o = 1;
+  () →* core::num* a = () → core::int* => i;
+  () →* core::num* b = () → core::num* => o as{TypeError} core::num*;
+  () →* core::num* c = () → core::int* {
+    return i;
+  };
+  () →* core::num* d = () → core::num* {
+    return o as{TypeError} core::num*;
+  };
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/lambda_void_context.dart.weak.modular.expect b/pkg/front_end/testcases/inference/lambda_void_context.dart.weak.modular.expect
new file mode 100644
index 0000000..bfc338c
--- /dev/null
+++ b/pkg/front_end/testcases/inference/lambda_void_context.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method f() → dynamic {
+  core::List<core::int*>* o;
+  o.{core::Iterable::forEach}((core::int* i) → core::int* => i.{core::num::+}(1){(core::num*) →* core::int*}){((core::int*) →* void) →* void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/list_literal_typed.dart.weak.modular.expect b/pkg/front_end/testcases/inference/list_literal_typed.dart.weak.modular.expect
new file mode 100644
index 0000000..87ba7a9
--- /dev/null
+++ b/pkg/front_end/testcases/inference/list_literal_typed.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<core::int*>* a = <core::int*>[];
+static field core::List<core::double*>* b = <core::double*>[1.0, 2.0, 3.0];
+static field core::List<core::List<core::int*>*>* c = <core::List<core::int*>*>[];
+static field core::List<dynamic>* d = <dynamic>[1, 2.0, false];
+static method main() → dynamic {
+  core::List<core::int*>* a = <core::int*>[];
+  core::List<core::double*>* b = <core::double*>[1.0, 2.0, 3.0];
+  core::List<core::List<core::int*>*>* c = <core::List<core::int*>*>[];
+  core::List<dynamic>* d = <dynamic>[1, 2.0, false];
+}
diff --git a/pkg/front_end/testcases/inference/list_literals.dart.weak.modular.expect b/pkg/front_end/testcases/inference/list_literals.dart.weak.modular.expect
new file mode 100644
index 0000000..a4e38e4
--- /dev/null
+++ b/pkg/front_end/testcases/inference/list_literals.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/list_literals.dart:10:70: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//   x. /*@target=List.add*/ add(/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi');
+//                                                                      ^
+//
+// pkg/front_end/testcases/inference/list_literals.dart:11:70: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+//   x. /*@target=List.add*/ add(/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 4.0);
+//                                                                      ^
+//
+// pkg/front_end/testcases/inference/list_literals.dart:18:70: Error: The argument type 'String' can't be assigned to the parameter type 'num'.
+//   x. /*@target=List.add*/ add(/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi');
+//                                                                      ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test1() → dynamic {
+  core::List<core::int*>* x = <core::int*>[1, 2, 3];
+  x.{core::List::add}(invalid-expression "pkg/front_end/testcases/inference/list_literals.dart:10:70: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+  x. /*@target=List.add*/ add(/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi');
+                                                                     ^" in "hi" as{TypeError} core::int*){(core::int*) →* void};
+  x.{core::List::add}(invalid-expression "pkg/front_end/testcases/inference/list_literals.dart:11:70: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+  x. /*@target=List.add*/ add(/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 4.0);
+                                                                     ^" in 4.0 as{TypeError} core::int*){(core::int*) →* void};
+  x.{core::List::add}(4){(core::int*) →* void};
+  core::List<core::num*>* y = x;
+}
+static method test2() → dynamic {
+  core::List<core::num*>* x = <core::num*>[1, 2.0, 3];
+  x.{core::List::add}(invalid-expression "pkg/front_end/testcases/inference/list_literals.dart:18:70: Error: The argument type 'String' can't be assigned to the parameter type 'num'.
+  x. /*@target=List.add*/ add(/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi');
+                                                                     ^" in "hi" as{TypeError} core::num*){(core::num*) →* void};
+  x.{core::List::add}(4.0){(core::num*) →* void};
+  core::List<core::int*>* y = x as{TypeError} core::List<core::int*>*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/list_literals_can_infer_null_bottom.dart.weak.modular.expect b/pkg/front_end/testcases/inference/list_literals_can_infer_null_bottom.dart.weak.modular.expect
new file mode 100644
index 0000000..6efc2e7
--- /dev/null
+++ b/pkg/front_end/testcases/inference/list_literals_can_infer_null_bottom.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test1() → dynamic {
+  core::List<Null>* x = <Null>[null];
+  x.{core::List::add}(42 as{TypeError} Null){(Null) →* void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/list_literals_top_level.dart.weak.modular.expect b/pkg/front_end/testcases/inference/list_literals_top_level.dart.weak.modular.expect
new file mode 100644
index 0000000..75f767f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/list_literals_top_level.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/list_literals_top_level.dart:10:71: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+//   x1. /*@target=List.add*/ add(/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi');
+//                                                                       ^
+//
+// pkg/front_end/testcases/inference/list_literals_top_level.dart:11:71: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+//   x1. /*@target=List.add*/ add(/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 4.0);
+//                                                                       ^
+//
+// pkg/front_end/testcases/inference/list_literals_top_level.dart:18:71: Error: The argument type 'String' can't be assigned to the parameter type 'num'.
+//   x2. /*@target=List.add*/ add(/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi');
+//                                                                       ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field core::List<core::int*>* x1 = <core::int*>[1, 2, 3];
+static field core::List<core::num*>* x2 = <core::num*>[1, 2.0, 3];
+static method test1() → dynamic {
+  self::x1.{core::List::add}(invalid-expression "pkg/front_end/testcases/inference/list_literals_top_level.dart:10:71: Error: The argument type 'String' can't be assigned to the parameter type 'int'.
+  x1. /*@target=List.add*/ add(/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi');
+                                                                      ^" in "hi" as{TypeError} core::int*){(core::int*) →* void};
+  self::x1.{core::List::add}(invalid-expression "pkg/front_end/testcases/inference/list_literals_top_level.dart:11:71: Error: The argument type 'double' can't be assigned to the parameter type 'int'.
+  x1. /*@target=List.add*/ add(/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 4.0);
+                                                                      ^" in 4.0 as{TypeError} core::int*){(core::int*) →* void};
+  self::x1.{core::List::add}(4){(core::int*) →* void};
+  core::List<core::num*>* y = self::x1;
+}
+static method test2() → dynamic {
+  self::x2.{core::List::add}(invalid-expression "pkg/front_end/testcases/inference/list_literals_top_level.dart:18:71: Error: The argument type 'String' can't be assigned to the parameter type 'num'.
+  x2. /*@target=List.add*/ add(/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi');
+                                                                      ^" in "hi" as{TypeError} core::num*){(core::num*) →* void};
+  self::x2.{core::List::add}(4.0){(core::num*) →* void};
+  core::List<core::int*>* y = self::x2 as{TypeError} core::List<core::int*>*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/local_constructor_from_arguments.dart.weak.modular.expect b/pkg/front_end/testcases/inference/local_constructor_from_arguments.dart.weak.modular.expect
new file mode 100644
index 0000000..908eca7
--- /dev/null
+++ b/pkg/front_end/testcases/inference/local_constructor_from_arguments.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::C::T* t;
+  constructor •(self::C::T* t) → self::C<self::C::T*>*
+    : self::C::t = t, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C<core::int*>* x = new self::C::•<core::int*>(42);
+  core::num* y;
+  self::C<core::int*>* c_int = new self::C::•<core::int*>(y as{TypeError} core::int*);
+  self::C<core::num*>* c_num = new self::C::•<core::num*>(123);
+  self::C<dynamic>* c_dynamic = new self::C::•<dynamic>(42);
+}
diff --git a/pkg/front_end/testcases/inference/local_reference_upwards_local.dart.weak.modular.expect b/pkg/front_end/testcases/inference/local_reference_upwards_local.dart.weak.modular.expect
new file mode 100644
index 0000000..220da3b
--- /dev/null
+++ b/pkg/front_end/testcases/inference/local_reference_upwards_local.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library test;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "dart:async";
+
+static method main() → dynamic {
+  asy::Future<core::int*>* futureInt = null;
+  asy::Future<core::int*>* x = futureInt;
+}
diff --git a/pkg/front_end/testcases/inference/local_return_and_yield.dart.weak.modular.expect b/pkg/front_end/testcases/inference/local_return_and_yield.dart.weak.modular.expect
new file mode 100644
index 0000000..421e71c
--- /dev/null
+++ b/pkg/front_end/testcases/inference/local_return_and_yield.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/local_return_and_yield.dart:19:38: Error: A value of type 'Future<dynamic Function(dynamic)>' can't be assigned to a variable of type 'FutureOr<int Function(int)>'.
+//  - 'Future' is from 'dart:async'.
+//     return /*@ returnType=dynamic */ (/*@ type=dynamic */ x) => x;
+//                                      ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+typedef IntToInt = (core::int*) →* core::int*;
+static method main() → dynamic {
+  function a() → (core::int*) →* core::int* {
+    return (core::int* x) → core::int* => x;
+  }
+  function b() → asy::Future<(core::int*) →* core::int*>* async {
+    return invalid-expression "pkg/front_end/testcases/inference/local_return_and_yield.dart:19:38: Error: A value of type 'Future<dynamic Function(dynamic)>' can't be assigned to a variable of type 'FutureOr<int Function(int)>'.
+ - 'Future' is from 'dart:async'.
+    return /*@ returnType=dynamic */ (/*@ type=dynamic */ x) => x;
+                                     ^" in ((dynamic x) → dynamic => x) as{TypeError} FutureOr<(core::int*) →* core::int*>*;
+  }
+  function c() → core::Iterable<(core::int*) →* core::int*>* sync* {
+    yield(core::int* x) → core::int* => x;
+  }
+  function d() → core::Iterable<(core::int*) →* core::int*>* sync* {
+    yield*<(core::int*) →* core::int*>[(core::int* x) → core::int* => x];
+  }
+  function e() → asy::Stream<(core::int*) →* core::int*>* async* {
+    yield(core::int* x) → core::int* => x;
+  }
+  function f() → asy::Stream<(core::int*) →* core::int*>* async* {
+    yield* asy::Stream::fromIterable<(core::int*) →* core::int*>(<(core::int*) →* core::int*>[(core::int* x) → core::int* => x]);
+  }
+}
diff --git a/pkg/front_end/testcases/inference/logical_or_promotion.dart.weak.modular.expect b/pkg/front_end/testcases/inference/logical_or_promotion.dart.weak.modular.expect
new file mode 100644
index 0000000..8b606cf
--- /dev/null
+++ b/pkg/front_end/testcases/inference/logical_or_promotion.dart.weak.modular.expect
@@ -0,0 +1,58 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  field self::A* a = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f(core::Object* o) → void {
+    if(o is self::A* || o is self::B*) {
+      if(o is self::A*) {
+        this.{self::C::a} = o{self::A*};
+      }
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/map_literals.dart.weak.modular.expect b/pkg/front_end/testcases/inference/map_literals.dart.weak.modular.expect
new file mode 100644
index 0000000..f3f2fd7
--- /dev/null
+++ b/pkg/front_end/testcases/inference/map_literals.dart.weak.modular.expect
@@ -0,0 +1,58 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/map_literals.dart:12:46: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//       /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi'] = 'w';
+//                                              ^
+//
+// pkg/front_end/testcases/inference/map_literals.dart:14:46: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//       /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 4.0] = 'u';
+//                                              ^
+//
+// pkg/front_end/testcases/inference/map_literals.dart:15:60: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   x /*@target=Map.[]=*/ [3] = /*error:INVALID_ASSIGNMENT*/ 42;
+//                                                            ^
+//
+// pkg/front_end/testcases/inference/map_literals.dart:27:46: Error: A value of type 'String' can't be assigned to a variable of type 'num'.
+//       /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi'] = 'w';
+//                                              ^
+//
+// pkg/front_end/testcases/inference/map_literals.dart:29:60: Error: A value of type 'int' can't be assigned to a variable of type 'Pattern'.
+//  - 'Pattern' is from 'dart:core'.
+//   x /*@target=Map.[]=*/ [3] = /*error:INVALID_ASSIGNMENT*/ 42;
+//                                                            ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test1() → dynamic {
+  core::Map<core::int*, core::String*>* x = <core::int*, core::String*>{1: "x", 2: "y"};
+  x.{core::Map::[]=}(3, "z"){(core::int*, core::String*) →* void};
+  x.{core::Map::[]=}(invalid-expression "pkg/front_end/testcases/inference/map_literals.dart:12:46: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+      /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi'] = 'w';
+                                             ^" in "hi" as{TypeError} core::int*, "w"){(core::int*, core::String*) →* void};
+  x.{core::Map::[]=}(invalid-expression "pkg/front_end/testcases/inference/map_literals.dart:14:46: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+      /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 4.0] = 'u';
+                                             ^" in 4.0 as{TypeError} core::int*, "u"){(core::int*, core::String*) →* void};
+  x.{core::Map::[]=}(3, invalid-expression "pkg/front_end/testcases/inference/map_literals.dart:15:60: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  x /*@target=Map.[]=*/ [3] = /*error:INVALID_ASSIGNMENT*/ 42;
+                                                           ^" in 42 as{TypeError} core::String*){(core::int*, core::String*) →* void};
+  core::Map<core::num*, core::String*>* y = x;
+}
+static method test2() → dynamic {
+  core::Map<core::num*, core::Pattern*>* x = <core::num*, core::Pattern*>{1: "x", 2: "y", 3.0: core::RegExp::•(".")};
+  x.{core::Map::[]=}(3, "z"){(core::num*, core::Pattern*) →* void};
+  x.{core::Map::[]=}(invalid-expression "pkg/front_end/testcases/inference/map_literals.dart:27:46: Error: A value of type 'String' can't be assigned to a variable of type 'num'.
+      /*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi'] = 'w';
+                                             ^" in "hi" as{TypeError} core::num*, "w"){(core::num*, core::Pattern*) →* void};
+  x.{core::Map::[]=}(4.0, "u"){(core::num*, core::Pattern*) →* void};
+  x.{core::Map::[]=}(3, invalid-expression "pkg/front_end/testcases/inference/map_literals.dart:29:60: Error: A value of type 'int' can't be assigned to a variable of type 'Pattern'.
+ - 'Pattern' is from 'dart:core'.
+  x /*@target=Map.[]=*/ [3] = /*error:INVALID_ASSIGNMENT*/ 42;
+                                                           ^" in 42 as{TypeError} core::Pattern*){(core::num*, core::Pattern*) →* void};
+  core::Pattern* p = null;
+  x.{core::Map::[]=}(2, p){(core::num*, core::Pattern*) →* void};
+  core::Map<core::int*, core::String*>* y = x as{TypeError} core::Map<core::int*, core::String*>*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/map_literals_can_infer_null.dart.weak.modular.expect b/pkg/front_end/testcases/inference/map_literals_can_infer_null.dart.weak.modular.expect
new file mode 100644
index 0000000..b636b6c
--- /dev/null
+++ b/pkg/front_end/testcases/inference/map_literals_can_infer_null.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test1() → dynamic {
+  core::Map<Null, Null>* x = <Null, Null>{null: null};
+  x.{core::Map::[]=}(3 as{TypeError} Null, "z" as{TypeError} Null){(Null, Null) →* void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/map_literals_top_level.dart.weak.modular.expect b/pkg/front_end/testcases/inference/map_literals_top_level.dart.weak.modular.expect
new file mode 100644
index 0000000..cd284fd
--- /dev/null
+++ b/pkg/front_end/testcases/inference/map_literals_top_level.dart.weak.modular.expect
@@ -0,0 +1,58 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/map_literals_top_level.dart:11:66: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   x1 /*@target=Map.[]=*/ [/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi'] = 'w';
+//                                                                  ^
+//
+// pkg/front_end/testcases/inference/map_literals_top_level.dart:12:66: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//   x1 /*@target=Map.[]=*/ [/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 4.0] = 'u';
+//                                                                  ^
+//
+// pkg/front_end/testcases/inference/map_literals_top_level.dart:13:61: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   x1 /*@target=Map.[]=*/ [3] = /*error:INVALID_ASSIGNMENT*/ 42;
+//                                                             ^
+//
+// pkg/front_end/testcases/inference/map_literals_top_level.dart:20:66: Error: A value of type 'String' can't be assigned to a variable of type 'num'.
+//   x2 /*@target=Map.[]=*/ [/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi'] = 'w';
+//                                                                  ^
+//
+// pkg/front_end/testcases/inference/map_literals_top_level.dart:22:61: Error: A value of type 'int' can't be assigned to a variable of type 'Pattern'.
+//  - 'Pattern' is from 'dart:core'.
+//   x2 /*@target=Map.[]=*/ [3] = /*error:INVALID_ASSIGNMENT*/ 42;
+//                                                             ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field core::Map<core::int*, core::String*>* x1 = <core::int*, core::String*>{1: "x", 2: "y"};
+static field core::Map<core::num*, core::Pattern*>* x2 = <core::num*, core::Pattern*>{1: "x", 2: "y", 3.0: core::RegExp::•(".")};
+static method test1() → dynamic {
+  self::x1.{core::Map::[]=}(3, "z"){(core::int*, core::String*) →* void};
+  self::x1.{core::Map::[]=}(invalid-expression "pkg/front_end/testcases/inference/map_literals_top_level.dart:11:66: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  x1 /*@target=Map.[]=*/ [/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi'] = 'w';
+                                                                 ^" in "hi" as{TypeError} core::int*, "w"){(core::int*, core::String*) →* void};
+  self::x1.{core::Map::[]=}(invalid-expression "pkg/front_end/testcases/inference/map_literals_top_level.dart:12:66: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  x1 /*@target=Map.[]=*/ [/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 4.0] = 'u';
+                                                                 ^" in 4.0 as{TypeError} core::int*, "u"){(core::int*, core::String*) →* void};
+  self::x1.{core::Map::[]=}(3, invalid-expression "pkg/front_end/testcases/inference/map_literals_top_level.dart:13:61: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  x1 /*@target=Map.[]=*/ [3] = /*error:INVALID_ASSIGNMENT*/ 42;
+                                                            ^" in 42 as{TypeError} core::String*){(core::int*, core::String*) →* void};
+  core::Map<core::num*, core::String*>* y = self::x1;
+}
+static method test2() → dynamic {
+  self::x2.{core::Map::[]=}(3, "z"){(core::num*, core::Pattern*) →* void};
+  self::x2.{core::Map::[]=}(invalid-expression "pkg/front_end/testcases/inference/map_literals_top_level.dart:20:66: Error: A value of type 'String' can't be assigned to a variable of type 'num'.
+  x2 /*@target=Map.[]=*/ [/*error:ARGUMENT_TYPE_NOT_ASSIGNABLE*/ 'hi'] = 'w';
+                                                                 ^" in "hi" as{TypeError} core::num*, "w"){(core::num*, core::Pattern*) →* void};
+  self::x2.{core::Map::[]=}(4.0, "u"){(core::num*, core::Pattern*) →* void};
+  self::x2.{core::Map::[]=}(3, invalid-expression "pkg/front_end/testcases/inference/map_literals_top_level.dart:22:61: Error: A value of type 'int' can't be assigned to a variable of type 'Pattern'.
+ - 'Pattern' is from 'dart:core'.
+  x2 /*@target=Map.[]=*/ [3] = /*error:INVALID_ASSIGNMENT*/ 42;
+                                                            ^" in 42 as{TypeError} core::Pattern*){(core::num*, core::Pattern*) →* void};
+  core::Pattern* p = null;
+  self::x2.{core::Map::[]=}(2, p){(core::num*, core::Pattern*) →* void};
+  core::Map<core::int*, core::String*>* y = self::x2 as{TypeError} core::Map<core::int*, core::String*>*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/method_call_with_type_arguments_instance_method.dart.weak.modular.expect b/pkg/front_end/testcases/inference/method_call_with_type_arguments_instance_method.dart.weak.modular.expect
new file mode 100644
index 0000000..05bd044
--- /dev/null
+++ b/pkg/front_end/testcases/inference/method_call_with_type_arguments_instance_method.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f<T extends core::Object* = dynamic>() → self::D<self::C::f::T*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::D<core::int*>* f = new self::C::•().{self::C::f}<core::int*>(){() →* self::D<core::int*>*};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/method_call_with_type_arguments_instance_method_identifier_sequence.dart.weak.modular.expect b/pkg/front_end/testcases/inference/method_call_with_type_arguments_instance_method_identifier_sequence.dart.weak.modular.expect
new file mode 100644
index 0000000..28c5383
--- /dev/null
+++ b/pkg/front_end/testcases/inference/method_call_with_type_arguments_instance_method_identifier_sequence.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f<T extends core::Object* = dynamic>() → self::D<self::C::f::T*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C* c;
+static field self::D<core::int*>* f = self::c.{self::C::f}<core::int*>(){() →* self::D<core::int*>*};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/method_call_with_type_arguments_static_method.dart.weak.modular.expect b/pkg/front_end/testcases/inference/method_call_with_type_arguments_static_method.dart.weak.modular.expect
new file mode 100644
index 0000000..b87237a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/method_call_with_type_arguments_static_method.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  static method f<T extends core::Object* = dynamic>() → self::D<self::C::f::T*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::D<core::int*>* f = self::C::f<core::int*>();
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/method_call_with_type_arguments_top_level_function.dart.weak.modular.expect b/pkg/front_end/testcases/inference/method_call_with_type_arguments_top_level_function.dart.weak.modular.expect
new file mode 100644
index 0000000..a32a635
--- /dev/null
+++ b/pkg/front_end/testcases/inference/method_call_with_type_arguments_top_level_function.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class D<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::D<core::int*>* g = self::f<core::int*>();
+static method f<T extends core::Object* = dynamic>() → self::D<self::f::T*>*
+  return null;
+static method main() → dynamic {
+  self::g;
+}
diff --git a/pkg/front_end/testcases/inference/mixin_inference_instantiate_to_bounds_1.dart.weak.modular.expect b/pkg/front_end/testcases/inference/mixin_inference_instantiate_to_bounds_1.dart.weak.modular.expect
new file mode 100644
index 0000000..ce1b438
--- /dev/null
+++ b/pkg/front_end/testcases/inference/mixin_inference_instantiate_to_bounds_1.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class I<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M0<X extends core::Object* = dynamic, Y extends core::String*> extends self::I<self::M0::X*> {
+  synthetic constructor •() → self::M0<self::M0::X*, self::M0::Y*>*
+    : super self::I::•()
+    ;
+}
+class M1 extends core::Object implements self::I<core::int*> {
+  synthetic constructor •() → self::M1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _A&M1&M0 = self::M1 with self::M0<core::int*, core::String*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A&M1&M0*
+    : super self::M1::•()
+    ;
+}
+class A extends self::_A&M1&M0 {
+  synthetic constructor •() → self::A*
+    : super self::_A&M1&M0::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/mixin_inference_instantiate_to_bounds_2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/mixin_inference_instantiate_to_bounds_2.dart.weak.modular.expect
new file mode 100644
index 0000000..f202e79
--- /dev/null
+++ b/pkg/front_end/testcases/inference/mixin_inference_instantiate_to_bounds_2.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class I<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M0<X extends core::Object* = dynamic, Y extends self::M0::X* = dynamic> extends self::I<self::M0::X*> {
+  synthetic constructor •() → self::M0<self::M0::X*, self::M0::Y*>*
+    : super self::I::•()
+    ;
+}
+class M1 extends core::Object implements self::I<core::int*> {
+  synthetic constructor •() → self::M1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _A&M1&M0 = self::M1 with self::M0<core::int*, core::int*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A&M1&M0*
+    : super self::M1::•()
+    ;
+}
+class A extends self::_A&M1&M0 {
+  synthetic constructor •() → self::A*
+    : super self::_A&M1&M0::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/mixin_inference_instantiate_to_bounds_3.dart.weak.modular.expect b/pkg/front_end/testcases/inference/mixin_inference_instantiate_to_bounds_3.dart.weak.modular.expect
new file mode 100644
index 0000000..69d5022
--- /dev/null
+++ b/pkg/front_end/testcases/inference/mixin_inference_instantiate_to_bounds_3.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/mixin_inference_instantiate_to_bounds_3.dart:13:7: Error: Type argument 'Comparable<dynamic>' doesn't conform to the bound 'Comparable<Y>' of the type variable 'Y' on 'M0' in the supertype 'M0' of class 'M1 with M0'.
+//  - 'Comparable' is from 'dart:core'.
+// Try changing type arguments so that they conform to the bounds.
+// class A extends M1 with M0 {}
+//       ^
+// pkg/front_end/testcases/inference/mixin_inference_instantiate_to_bounds_3.dart:7:13: Context: This is the type variable whose bound isn't conformed to.
+// class M0<X, Y extends Comparable<Y>> extends I<X> {}
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+class I<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M0<X extends core::Object* = dynamic, Y extends core::Comparable<self::M0::Y*>* = core::Comparable<dynamic>*> extends self::I<self::M0::X*> {
+  synthetic constructor •() → self::M0<self::M0::X*, self::M0::Y*>*
+    : super self::I::•()
+    ;
+}
+class M1 extends core::Object implements self::I<core::int*> {
+  synthetic constructor •() → self::M1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _A&M1&M0 = self::M1 with self::M0<core::int*, core::Comparable<dynamic>*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A&M1&M0*
+    : super self::M1::•()
+    ;
+}
+class A extends self::_A&M1&M0 {
+  synthetic constructor •() → self::A*
+    : super self::_A&M1&M0::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/mixin_inference_instantiate_to_bounds_4.dart.weak.modular.expect b/pkg/front_end/testcases/inference/mixin_inference_instantiate_to_bounds_4.dart.weak.modular.expect
new file mode 100644
index 0000000..4493630
--- /dev/null
+++ b/pkg/front_end/testcases/inference/mixin_inference_instantiate_to_bounds_4.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class I<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M0<X extends core::Object* = dynamic, Y extends ({name: core::String*}) →* void> extends self::I<self::M0::X*> {
+  synthetic constructor •() → self::M0<self::M0::X*, self::M0::Y*>*
+    : super self::I::•()
+    ;
+}
+class M1 extends core::Object implements self::I<core::int*> {
+  synthetic constructor •() → self::M1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _A&M1&M0 = self::M1 with self::M0<core::int*, ({name: core::String*}) →* void> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A&M1&M0*
+    : super self::M1::•()
+    ;
+}
+class A extends self::_A&M1&M0 {
+  synthetic constructor •() → self::A*
+    : super self::_A&M1&M0::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/mixin_inference_multiple_constraints.dart.weak.modular.expect b/pkg/front_end/testcases/inference/mixin_inference_multiple_constraints.dart.weak.modular.expect
new file mode 100644
index 0000000..4f31d67
--- /dev/null
+++ b/pkg/front_end/testcases/inference/mixin_inference_multiple_constraints.dart.weak.modular.expect
@@ -0,0 +1,75 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class I<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class J<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::J<self::J::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _M0&I&J<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> = self::I<self::_M0&I&J::X*> with self::J<self::_M0&I&J::Y*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_M0&I&J<self::_M0&I&J::X*, self::_M0&I&J::Y*>*
+    : super self::I::•()
+    ;
+}
+class M0<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends self::_M0&I&J<self::M0::X*, self::M0::Y*> {
+  synthetic constructor •() → self::M0<self::M0::X*, self::M0::Y*>*
+    : super self::_M0&I&J::•()
+    ;
+}
+class M1 extends core::Object implements self::I<core::int*> {
+  synthetic constructor •() → self::M1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M2 extends self::M1 implements self::J<core::double*> {
+  synthetic constructor •() → self::M2*
+    : super self::M1::•()
+    ;
+}
+abstract class _A&M2&M0 = self::M2 with self::M0<core::int*, core::double*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A&M2&M0*
+    : super self::M2::•()
+    ;
+}
+class A extends self::_A&M2&M0 {
+  synthetic constructor •() → self::A*
+    : super self::_A&M2&M0::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/mixin_inference_non_trivial_constraints.dart.weak.modular.expect b/pkg/front_end/testcases/inference/mixin_inference_non_trivial_constraints.dart.weak.modular.expect
new file mode 100644
index 0000000..012dd24
--- /dev/null
+++ b/pkg/front_end/testcases/inference/mixin_inference_non_trivial_constraints.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class I<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M0<T extends core::Object* = dynamic> extends self::I<core::List<self::M0::T*>*> {
+  synthetic constructor •() → self::M0<self::M0::T*>*
+    : super self::I::•()
+    ;
+}
+class M1<T extends core::Object* = dynamic> extends self::I<core::List<self::M1::T*>*> {
+  synthetic constructor •() → self::M1<self::M1::T*>*
+    : super self::I::•()
+    ;
+}
+class M2<T extends core::Object* = dynamic> extends self::M1<core::Map<self::M2::T*, self::M2::T*>*> {
+  synthetic constructor •() → self::M2<self::M2::T*>*
+    : super self::M1::•()
+    ;
+}
+abstract class _A&M2&M0 = self::M2<core::int*> with self::M0<core::Map<core::int*, core::int*>*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A&M2&M0*
+    : super self::M2::•()
+    ;
+}
+class A extends self::_A&M2&M0 {
+  synthetic constructor •() → self::A*
+    : super self::_A&M2&M0::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/mixin_inference_outwards_1.dart.weak.modular.expect b/pkg/front_end/testcases/inference/mixin_inference_outwards_1.dart.weak.modular.expect
new file mode 100644
index 0000000..0f8933b
--- /dev/null
+++ b/pkg/front_end/testcases/inference/mixin_inference_outwards_1.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class I<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M0<T extends core::Object* = dynamic> extends self::I<self::M0::T*> {
+  synthetic constructor •() → self::M0<self::M0::T*>*
+    : super self::I::•()
+    ;
+}
+class M1<T extends core::Object* = dynamic> extends self::I<self::M1::T*> {
+  synthetic constructor •() → self::M1<self::M1::T*>*
+    : super self::I::•()
+    ;
+}
+abstract class _A&M0&M1 = self::M0<core::int*> with self::M1<core::int*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A&M0&M1*
+    : super self::M0::•()
+    ;
+}
+class A extends self::_A&M0&M1 {
+  synthetic constructor •() → self::A*
+    : super self::_A&M0&M1::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/mixin_inference_outwards_2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/mixin_inference_outwards_2.dart.weak.modular.expect
new file mode 100644
index 0000000..d7c017d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/mixin_inference_outwards_2.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class I<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M0<T extends core::Object* = dynamic> extends self::I<self::M0::T*> {
+  synthetic constructor •() → self::M0<self::M0::T*>*
+    : super self::I::•()
+    ;
+}
+class M1<T extends core::Object* = dynamic> extends self::I<self::M1::T*> {
+  synthetic constructor •() → self::M1<self::M1::T*>*
+    : super self::I::•()
+    ;
+}
+class M2<T extends core::Object* = dynamic> extends self::I<self::M2::T*> {
+  synthetic constructor •() → self::M2<self::M2::T*>*
+    : super self::I::•()
+    ;
+}
+abstract class _A&M0&M1 = self::M0<core::int*> with self::M1<core::int*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A&M0&M1*
+    : super self::M0::•()
+    ;
+}
+abstract class _A&M0&M1&M2 = self::_A&M0&M1 with self::M2<core::int*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A&M0&M1&M2*
+    : super self::_A&M0&M1::•()
+    ;
+}
+class A extends self::_A&M0&M1&M2 {
+  synthetic constructor •() → self::A*
+    : super self::_A&M0&M1&M2::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/mixin_inference_outwards_3.dart.weak.modular.expect b/pkg/front_end/testcases/inference/mixin_inference_outwards_3.dart.weak.modular.expect
new file mode 100644
index 0000000..da805eec
--- /dev/null
+++ b/pkg/front_end/testcases/inference/mixin_inference_outwards_3.dart.weak.modular.expect
@@ -0,0 +1,73 @@
+//
+// Problems in component:
+//
+// pkg/front_end/testcases/inference/mixin_inference_outwards_3.dart:13:7: Error: 'Object with M0, M1' can't implement both 'I<dynamic>' and 'I<int>'
+//  - 'I' is from 'pkg/front_end/testcases/inference/mixin_inference_outwards_3.dart'.
+// class A extends Object with M0, M1<int> {}
+//       ^
+//
+library;
+import self as self;
+import "dart:core" as core;
+
+class I<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M0<T extends core::Object* = dynamic> extends core::Object implements self::I<self::M0::T*> {
+  synthetic constructor •() → self::M0<self::M0::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M1<T extends core::Object* = dynamic> extends self::I<self::M1::T*> {
+  synthetic constructor •() → self::M1<self::M1::T*>*
+    : super self::I::•()
+    ;
+}
+abstract class _A&Object&M0 = core::Object with self::M0<dynamic> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_A&Object&M0*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _A&Object&M0&M1 = self::_A&Object&M0 with self::M1<core::int*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_A&Object&M0&M1*
+    : super self::_A&Object&M0::•()
+    ;
+}
+class A extends self::_A&Object&M0&M1 {
+  synthetic constructor •() → self::A*
+    : super self::_A&Object&M0&M1::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/mixin_inference_outwards_4.dart.weak.modular.expect b/pkg/front_end/testcases/inference/mixin_inference_outwards_4.dart.weak.modular.expect
new file mode 100644
index 0000000..1391478
--- /dev/null
+++ b/pkg/front_end/testcases/inference/mixin_inference_outwards_4.dart.weak.modular.expect
@@ -0,0 +1,73 @@
+//
+// Problems in component:
+//
+// pkg/front_end/testcases/inference/mixin_inference_outwards_4.dart:14:7: Error: 'A' can't implement both 'I<dynamic>' and 'I<int>'
+//  - 'I' is from 'pkg/front_end/testcases/inference/mixin_inference_outwards_4.dart'.
+// class A extends Object with M0, M1 implements I<int> {}
+//       ^
+//
+library;
+import self as self;
+import "dart:core" as core;
+
+class I<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M0<T extends core::Object* = dynamic> extends core::Object implements self::I<self::M0::T*> {
+  synthetic constructor •() → self::M0<self::M0::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M1<T extends core::Object* = dynamic> extends self::I<self::M1::T*> {
+  synthetic constructor •() → self::M1<self::M1::T*>*
+    : super self::I::•()
+    ;
+}
+abstract class _A&Object&M0 = core::Object with self::M0<dynamic> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_A&Object&M0*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _A&Object&M0&M1 = self::_A&Object&M0 with self::M1<dynamic> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_A&Object&M0&M1*
+    : super self::_A&Object&M0::•()
+    ;
+}
+class A extends self::_A&Object&M0&M1 implements self::I<core::int*> {
+  synthetic constructor •() → self::A*
+    : super self::_A&Object&M0&M1::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/mixin_inference_unification_1.dart.weak.modular.expect b/pkg/front_end/testcases/inference/mixin_inference_unification_1.dart.weak.modular.expect
new file mode 100644
index 0000000..5907e7e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/mixin_inference_unification_1.dart.weak.modular.expect
@@ -0,0 +1,83 @@
+//
+// Problems in component:
+//
+// pkg/front_end/testcases/inference/mixin_inference_unification_1.dart:13:7: Error: 'Object with M0, M1' can't implement both 'I<dynamic, int>' and 'I<String, dynamic>'
+//  - 'I' is from 'pkg/front_end/testcases/inference/mixin_inference_unification_1.dart'.
+// class A extends Object with M0, M1 {}
+//       ^
+//
+library;
+import self as self;
+import "dart:core" as core;
+
+class I<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::X*, self::I::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M0<T extends core::Object* = dynamic> extends core::Object implements self::I<self::M0::T*, core::int*> {
+  synthetic constructor •() → self::M0<self::M0::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M1<T extends core::Object* = dynamic> extends core::Object implements self::I<core::String*, self::M1::T*> {
+  synthetic constructor •() → self::M1<self::M1::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _A&Object&M0 = core::Object with self::M0<dynamic> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_A&Object&M0*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _A&Object&M0&M1 = self::_A&Object&M0 with self::M1<dynamic> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_A&Object&M0&M1*
+    : super self::_A&Object&M0::•()
+    ;
+}
+class A extends self::_A&Object&M0&M1 {
+  synthetic constructor •() → self::A*
+    : super self::_A&Object&M0&M1::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/mixin_inference_unification_2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/mixin_inference_unification_2.dart.weak.modular.expect
new file mode 100644
index 0000000..41a47e4
--- /dev/null
+++ b/pkg/front_end/testcases/inference/mixin_inference_unification_2.dart.weak.modular.expect
@@ -0,0 +1,84 @@
+//
+// Problems in component:
+//
+// pkg/front_end/testcases/inference/mixin_inference_unification_2.dart:17:7: Error: 'Object with M0, M1' can't implement both 'I<dynamic, List<dynamic>>' and 'I<List<dynamic>, dynamic>'
+//  - 'I' is from 'pkg/front_end/testcases/inference/mixin_inference_unification_2.dart'.
+//  - 'List' is from 'dart:core'.
+// class A extends Object with M0, M1 {}
+//       ^
+//
+library;
+import self as self;
+import "dart:core" as core;
+
+class I<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::X*, self::I::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M0<T extends core::Object* = dynamic> extends core::Object implements self::I<self::M0::T*, core::List<self::M0::T*>*> {
+  synthetic constructor •() → self::M0<self::M0::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M1<T extends core::Object* = dynamic> extends core::Object implements self::I<core::List<self::M1::T*>*, self::M1::T*> {
+  synthetic constructor •() → self::M1<self::M1::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _A&Object&M0 = core::Object with self::M0<dynamic> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_A&Object&M0*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _A&Object&M0&M1 = self::_A&Object&M0 with self::M1<dynamic> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_A&Object&M0&M1*
+    : super self::_A&Object&M0::•()
+    ;
+}
+class A extends self::_A&Object&M0&M1 {
+  synthetic constructor •() → self::A*
+    : super self::_A&Object&M0&M1::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/no_error_when_declared_type_is_num_and_assigned_null.dart.weak.modular.expect b/pkg/front_end/testcases/inference/no_error_when_declared_type_is_num_and_assigned_null.dart.weak.modular.expect
new file mode 100644
index 0000000..fb95dc3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/no_error_when_declared_type_is_num_and_assigned_null.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test1() → dynamic {
+  core::num* x = 3;
+  x = null;
+}
+static method main() → dynamic {
+  self::test1();
+}
diff --git a/pkg/front_end/testcases/inference/non_const_invocation.dart.weak.modular.expect b/pkg/front_end/testcases/inference/non_const_invocation.dart.weak.modular.expect
new file mode 100644
index 0000000..5049806
--- /dev/null
+++ b/pkg/front_end/testcases/inference/non_const_invocation.dart.weak.modular.expect
@@ -0,0 +1,54 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant U extends core::Object* = dynamic, V extends core::Object* = dynamic> = (U*) →* V*;
+class Foo<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Foo<self::Foo::T*>*
+    : super core::Object::•()
+    ;
+  get v1() → self::Bar<self::Foo::T*>*
+    return new self::Bar::•<self::Foo::T*>();
+  get v2() → self::Bar<core::List<self::Foo::T*>*>*
+    return new self::Bar::•<core::List<self::Foo::T*>*>();
+  get v3() → self::Bar<(self::Foo::T*) →* self::Foo::T*>*
+    return new self::Bar::•<(self::Foo::T*) →* self::Foo::T*>();
+  get v4() → self::Bar<((self::Foo::T*) →* self::Foo::T*) →* self::Foo::T*>*
+    return new self::Bar::•<((self::Foo::T*) →* self::Foo::T*) →* self::Foo::T*>();
+  get v5() → core::List<self::Foo::T*>*
+    return <self::Foo::T*>[];
+  get v6() → core::List<(self::Foo::T*) →* self::Foo::T*>*
+    return <(self::Foo::T*) →* self::Foo::T*>[];
+  get v7() → core::Map<self::Foo::T*, self::Foo::T*>*
+    return <self::Foo::T*, self::Foo::T*>{};
+  get v8() → core::Map<(self::Foo::T*) →* self::Foo::T*, self::Foo::T*>*
+    return <(self::Foo::T*) →* self::Foo::T*, self::Foo::T*>{};
+  get v9() → core::Map<self::Foo::T*, (self::Foo::T*) →* self::Foo::T*>*
+    return <self::Foo::T*, (self::Foo::T*) →* self::Foo::T*>{};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar<T extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::Bar<self::Bar::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/non_inferrable_getter_setter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/non_inferrable_getter_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..8a5e873
--- /dev/null
+++ b/pkg/front_end/testcases/inference/non_inferrable_getter_setter.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  get x() → dynamic
+    return null;
+  set x(dynamic value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/null_aware_method_invocation.dart.weak.modular.expect b/pkg/front_end/testcases/inference/null_aware_method_invocation.dart.weak.modular.expect
new file mode 100644
index 0000000..cbf7329
--- /dev/null
+++ b/pkg/front_end/testcases/inference/null_aware_method_invocation.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f() → core::int*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g(self::C* c) → dynamic {
+  core::int* x = let final self::C* #t1 = c in #t1 == null ?{core::int*} null : #t1.{self::C::f}(){() →* core::int*};
+  let final self::C* #t2 = c in #t2 == null ?{core::int*} null : #t2.{self::C::f}(){() →* core::int*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/null_aware_property_get.dart.weak.modular.expect b/pkg/front_end/testcases/inference/null_aware_property_get.dart.weak.modular.expect
new file mode 100644
index 0000000..b8c3acb
--- /dev/null
+++ b/pkg/front_end/testcases/inference/null_aware_property_get.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field core::int* x = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f(self::C* c) → void {
+  core::int* x = let final self::C* #t1 = c in #t1 == null ?{core::int*} null : #t1.{self::C::x}{core::int*};
+  let final self::C* #t2 = c in #t2 == null ?{core::int*} null : #t2.{self::C::x}{core::int*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/null_coalescing_operator.dart.weak.modular.expect b/pkg/front_end/testcases/inference/null_coalescing_operator.dart.weak.modular.expect
new file mode 100644
index 0000000..15f12a3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/null_coalescing_operator.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::List<core::int*>* x;
+  core::List<core::int*>* y = let final core::List<core::int*>* #t1 = x in #t1 == null ?{core::List<core::int*>*} <core::int*>[] : #t1;
+  core::List<core::int*>* z = y;
+}
diff --git a/pkg/front_end/testcases/inference/null_coalescing_operator_2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/null_coalescing_operator_2.dart.weak.modular.expect
new file mode 100644
index 0000000..33d1268
--- /dev/null
+++ b/pkg/front_end/testcases/inference/null_coalescing_operator_2.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::List<core::int*>* x;
+  core::List<core::num*>* y = let final core::List<core::int*>* #t1 = x in #t1 == null ?{core::List<core::num*>*} <core::num*>[] : #t1;
+}
diff --git a/pkg/front_end/testcases/inference/null_literal_should_not_infer_as_bottom.dart.weak.modular.expect b/pkg/front_end/testcases/inference/null_literal_should_not_infer_as_bottom.dart.weak.modular.expect
new file mode 100644
index 0000000..4344e6b
--- /dev/null
+++ b/pkg/front_end/testcases/inference/null_literal_should_not_infer_as_bottom.dart.weak.modular.expect
@@ -0,0 +1,19 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field dynamic h = null;
+static method foo((core::Object*) →* core::int* f) → void {}
+static method test() → dynamic {
+  (core::Object*) →* Null f = (core::Object* x) → Null => null;
+  core::String* y = f(42){(core::Object*) →* Null};
+  f = (core::Object* x) → Null => "hello" as{TypeError} Null;
+  dynamic g = null;
+  g = "hello";
+  g{dynamic}.foo();
+  self::h = "hello";
+  self::h{dynamic}.foo();
+  self::foo((core::Object* x) → Null => null);
+  self::foo((core::Object* x) → Null => throw "not implemented");
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/overloaded_int_operators.dart.weak.modular.expect b/pkg/front_end/testcases/inference/overloaded_int_operators.dart.weak.modular.expect
new file mode 100644
index 0000000..09b660d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/overloaded_int_operators.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::num* n = 1;
+  core::int* i = 1;
+  core::double* d = 1.0;
+  core::double* ddPlus = d.{core::double::+}(d){(core::num*) →* core::double*};
+  core::double* ddMinus = d.{core::double::-}(d){(core::num*) →* core::double*};
+  core::double* ddTimes = d.{core::double::*}(d){(core::num*) →* core::double*};
+  core::double* ddMod = d.{core::double::%}(d){(core::num*) →* core::double*};
+  core::double* diPlus = d.{core::double::+}(i){(core::num*) →* core::double*};
+  core::double* diMinus = d.{core::double::-}(i){(core::num*) →* core::double*};
+  core::double* diTimes = d.{core::double::*}(i){(core::num*) →* core::double*};
+  core::double* diMod = d.{core::double::%}(i){(core::num*) →* core::double*};
+  core::double* dnPlus = d.{core::double::+}(n){(core::num*) →* core::double*};
+  core::double* dnMinus = d.{core::double::-}(n){(core::num*) →* core::double*};
+  core::double* dnTimes = d.{core::double::*}(n){(core::num*) →* core::double*};
+  core::double* dnMod = d.{core::double::%}(n){(core::num*) →* core::double*};
+  core::double* idPlus = i.{core::num::+}(d){(core::num*) →* core::double*};
+  core::double* idMinus = i.{core::num::-}(d){(core::num*) →* core::double*};
+  core::double* idTimes = i.{core::num::*}(d){(core::num*) →* core::double*};
+  core::double* idMod = i.{core::num::%}(d){(core::num*) →* core::double*};
+  core::int* iiPlus = i.{core::num::+}(i){(core::num*) →* core::int*};
+  core::int* iiMinus = i.{core::num::-}(i){(core::num*) →* core::int*};
+  core::int* iiTimes = i.{core::num::*}(i){(core::num*) →* core::int*};
+  core::int* iiMod = i.{core::num::%}(i){(core::num*) →* core::int*};
+  core::num* inPlus = i.{core::num::+}(n){(core::num*) →* core::num*};
+  core::num* inMinus = i.{core::num::-}(n){(core::num*) →* core::num*};
+  core::num* inTimes = i.{core::num::*}(n){(core::num*) →* core::num*};
+  core::num* inMod = i.{core::num::%}(n){(core::num*) →* core::num*};
+  core::num* ndPlus = n.{core::num::+}(d){(core::num*) →* core::num*};
+  core::num* ndMinus = n.{core::num::-}(d){(core::num*) →* core::num*};
+  core::num* ndTimes = n.{core::num::*}(d){(core::num*) →* core::num*};
+  core::num* ndMod = n.{core::num::%}(d){(core::num*) →* core::num*};
+  core::num* niPlus = n.{core::num::+}(i){(core::num*) →* core::num*};
+  core::num* niMinus = n.{core::num::-}(i){(core::num*) →* core::num*};
+  core::num* niTimes = n.{core::num::*}(i){(core::num*) →* core::num*};
+  core::num* niMod = n.{core::num::%}(i){(core::num*) →* core::num*};
+  core::num* nnPlus = n.{core::num::+}(n){(core::num*) →* core::num*};
+  core::num* nnMinus = n.{core::num::-}(n){(core::num*) →* core::num*};
+  core::num* nnTimes = n.{core::num::*}(n){(core::num*) →* core::num*};
+  core::num* nnMod = n.{core::num::%}(n){(core::num*) →* core::num*};
+}
diff --git a/pkg/front_end/testcases/inference/override_equals.dart.weak.modular.expect b/pkg/front_end/testcases/inference/override_equals.dart.weak.modular.expect
new file mode 100644
index 0000000..736b7cd
--- /dev/null
+++ b/pkg/front_end/testcases/inference/override_equals.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class NullEquality extends core::Object {
+  synthetic constructor •() → self::NullEquality*
+    : super core::Object::•()
+    ;
+  @#C1
+  operator ==(core::Object* other) → Null
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class SubNullEquality extends self::NullEquality {
+  synthetic constructor •() → self::SubNullEquality*
+    : super self::NullEquality::•()
+    ;
+  method test() → void {
+    core::bool* super_equals_self = super.{self::NullEquality::==}(this);
+    core::bool* super_equals_null = super.{self::NullEquality::==}(null);
+    core::bool* super_not_equals_self = !super.{self::NullEquality::==}(this);
+    core::bool* super_not_equals_null = !super.{self::NullEquality::==}(null);
+  }
+}
+static method test() → dynamic {
+  self::NullEquality* n = new self::NullEquality::•();
+  core::bool* equals_self = n =={self::NullEquality::==}{(core::Object*) →* Null} n;
+  core::bool* equals_null = n == null;
+  core::bool* null_equals = n == null;
+  core::bool* not_equals_self = !(n =={self::NullEquality::==}{(core::Object*) →* Null} n);
+  core::bool* not_equals_null = !(n == null);
+  core::bool* null_not_equals = !(n == null);
+}
+static method main() → dynamic {
+  self::test();
+  new self::SubNullEquality::•().{self::SubNullEquality::test}(){() →* void};
+}
+
+constants  {
+  #C1 = core::_Override {}
+}
diff --git a/pkg/front_end/testcases/inference/override_inference_depends_on_field_inference.dart.weak.modular.expect b/pkg/front_end/testcases/inference/override_inference_depends_on_field_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..d9defc4
--- /dev/null
+++ b/pkg/front_end/testcases/inference/override_inference_depends_on_field_inference.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object* = dynamic> extends core::Object {
+  final field core::String* foo = "bar";
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<Y extends core::Object* = dynamic> extends self::A<self::B::Y*> {
+  final field core::String* foo;
+  constructor •(core::String* foo) → self::B<self::B::Y*>*
+    : self::B::foo = foo, super self::A::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/override_inference_with_type_parameters.dart.weak.modular.expect b/pkg/front_end/testcases/inference/override_inference_with_type_parameters.dart.weak.modular.expect
new file mode 100644
index 0000000..4e88a92
--- /dev/null
+++ b/pkg/front_end/testcases/inference/override_inference_with_type_parameters.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class A<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract method foo({covariant-by-class core::Iterable<self::A::X*>* x = #C1}) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<Y extends core::Object* = dynamic> extends core::Object implements self::A<self::B::Y*> {
+  synthetic constructor •() → self::B<self::B::Y*>*
+    : super core::Object::•()
+    ;
+  method foo({covariant-by-class core::Iterable<self::B::Y*>* x = #C1}) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/inference/parameter_defaults_downwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/parameter_defaults_downwards.dart.weak.modular.expect
new file mode 100644
index 0000000..b20f8c7
--- /dev/null
+++ b/pkg/front_end/testcases/inference/parameter_defaults_downwards.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method optional_toplevel([core::List<core::int*>* x = #C1]) → void {}
+static method named_toplevel({core::List<core::int*>* x = #C1}) → void {}
+static method main() → dynamic {
+  function optional_local([core::List<core::int*>* x = #C1]) → void {}
+  function named_local({core::List<core::int*>* x = #C1}) → void {}
+  ([core::List<core::int*>*]) →* Null optional_closure = ([core::List<core::int*>* x = #C1]) → Null {};
+  ({x: core::List<core::int*>*}) →* Null name_closure = ({core::List<core::int*>* x = #C1}) → Null {};
+}
+
+constants  {
+  #C1 = <core::int*>[]
+}
diff --git a/pkg/front_end/testcases/inference/parameter_defaults_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference/parameter_defaults_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..d6fb1da
--- /dev/null
+++ b/pkg/front_end/testcases/inference/parameter_defaults_upwards.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  constructor optional(([self::C::T*]) →* void func) → self::C<self::C::T*>*
+    : super core::Object::•() {}
+  constructor named(({x: self::C::T*}) →* void func) → self::C<self::C::T*>*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method optional_toplevel([dynamic x = #C2]) → void {}
+static method named_toplevel({dynamic x = #C2}) → void {}
+static method main() → dynamic {
+  function optional_local([dynamic x = #C2]) → void {}
+  function named_local({dynamic x = #C2}) → void {}
+  self::C<dynamic>* c_optional_toplevel = new self::C::optional<dynamic>(#C3);
+  self::C<dynamic>* c_named_toplevel = new self::C::named<dynamic>(#C4);
+  self::C<dynamic>* c_optional_local = new self::C::optional<dynamic>(optional_local);
+  self::C<dynamic>* c_named_local = new self::C::named<dynamic>(named_local);
+  self::C<dynamic>* c_optional_closure = new self::C::optional<dynamic>(([dynamic x = #C2]) → Null {});
+  self::C<dynamic>* c_named_closure = new self::C::named<dynamic>(({dynamic x = #C2}) → Null {});
+}
+
+constants  {
+  #C1 = 0
+  #C2 = <core::int*>[#C1]
+  #C3 = static-tearoff self::optional_toplevel
+  #C4 = static-tearoff self::named_toplevel
+}
diff --git a/pkg/front_end/testcases/inference/promote_bounds.dart.weak.modular.expect b/pkg/front_end/testcases/inference/promote_bounds.dart.weak.modular.expect
new file mode 100644
index 0000000..cdec2e88
--- /dev/null
+++ b/pkg/front_end/testcases/inference/promote_bounds.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract method foo() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  abstract method bar() → void;
+}
+static method f<T extends self::B*>(self::f::T* a) → void {
+  if(a is core::String*) {
+    a.{self::B::foo}(){() →* void};
+  }
+  if(a is self::C*) {
+    a{self::f::T* & self::C* /* '*' & '*' = '*' */}.{self::C::bar}(){() →* void};
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/promote_from_logical_rhs.dart.weak.modular.expect b/pkg/front_end/testcases/inference/promote_from_logical_rhs.dart.weak.modular.expect
new file mode 100644
index 0000000..16ae59d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/promote_from_logical_rhs.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test(core::Object* a, core::bool* b) → void {
+  if(b && a is core::int*) {
+    core::print(a{core::int*});
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/promotion_subtype_check.dart.weak.modular.expect b/pkg/front_end/testcases/inference/promotion_subtype_check.dart.weak.modular.expect
new file mode 100644
index 0000000..f240935
--- /dev/null
+++ b/pkg/front_end/testcases/inference/promotion_subtype_check.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method f(core::Object* x) → void {
+  if(x is core::int*) {
+    if(x{core::int*} is core::String*) {
+      core::int* y = x{core::int*};
+    }
+  }
+}
+static method g(core::int* x) → void {
+  if(x is core::String*) {
+    core::int* y = x;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/propagate_inference_to_field_in_class.dart.weak.modular.expect b/pkg/front_end/testcases/inference/propagate_inference_to_field_in_class.dart.weak.modular.expect
new file mode 100644
index 0000000..3e27040
--- /dev/null
+++ b/pkg/front_end/testcases/inference/propagate_inference_to_field_in_class.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* x = 2;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::A* a = new self::A::•();
+  self::A* b = a;
+  core::print(a.{self::A::x}{core::int*});
+  core::print(a.{self::A::x}{core::int*}.{core::num::+}(2){(core::num*) →* core::int*});
+}
diff --git a/pkg/front_end/testcases/inference/propagate_inference_to_field_in_class_dynamic_warnings.dart.weak.modular.expect b/pkg/front_end/testcases/inference/propagate_inference_to_field_in_class_dynamic_warnings.dart.weak.modular.expect
new file mode 100644
index 0000000..06148db
--- /dev/null
+++ b/pkg/front_end/testcases/inference/propagate_inference_to_field_in_class_dynamic_warnings.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* x = 2;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  dynamic a = new self::A::•();
+  self::A* b = a as{TypeError,ForDynamic} self::A*;
+  core::print(a{dynamic}.x);
+  core::print(a{dynamic}.x{dynamic}.+(2));
+}
diff --git a/pkg/front_end/testcases/inference/propagate_inference_transitively.dart.weak.modular.expect b/pkg/front_end/testcases/inference/propagate_inference_transitively.dart.weak.modular.expect
new file mode 100644
index 0000000..81035d4
--- /dev/null
+++ b/pkg/front_end/testcases/inference/propagate_inference_transitively.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/propagate_inference_transitively.dart:14:56: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   a1. /*@target=A.x*/ x = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                                        ^
+//
+// pkg/front_end/testcases/inference/propagate_inference_transitively.dart:17:56: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+//   a2. /*@target=A.x*/ x = /*error:INVALID_ASSIGNMENT*/ "hi";
+//                                                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* x = 2;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test5() → dynamic {
+  self::A* a1 = new self::A::•();
+  a1.{self::A::x} = invalid-expression "pkg/front_end/testcases/inference/propagate_inference_transitively.dart:14:56: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  a1. /*@target=A.x*/ x = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                                       ^" in "hi" as{TypeError} core::int*;
+  self::A* a2 = new self::A::•();
+  a2.{self::A::x} = invalid-expression "pkg/front_end/testcases/inference/propagate_inference_transitively.dart:17:56: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+  a2. /*@target=A.x*/ x = /*error:INVALID_ASSIGNMENT*/ \"hi\";
+                                                       ^" in "hi" as{TypeError} core::int*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/propagate_inference_transitively2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/propagate_inference_transitively2.dart.weak.modular.expect
new file mode 100644
index 0000000..91157a6
--- /dev/null
+++ b/pkg/front_end/testcases/inference/propagate_inference_transitively2.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* x = 42;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  field self::A* a = new self::A::•();
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  field self::B* b = new self::B::•();
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends core::Object {
+  field self::C* c = new self::C::•();
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {
+  self::D* d1 = new self::D::•();
+  core::print(d1.{self::D::c}{self::C*}.{self::C::b}{self::B*}.{self::B::a}{self::A*}.{self::A::x}{core::int*});
+  self::D* d2 = new self::D::•();
+  core::print(d2.{self::D::c}{self::C*}.{self::C::b}{self::B*}.{self::B::a}{self::A*}.{self::A::x}{core::int*});
+}
diff --git a/pkg/front_end/testcases/inference/propagate_variable_get.dart.weak.modular.expect b/pkg/front_end/testcases/inference/propagate_variable_get.dart.weak.modular.expect
new file mode 100644
index 0000000..ba60f97
--- /dev/null
+++ b/pkg/front_end/testcases/inference/propagate_variable_get.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::int* a = 0;
+  core::int* b = a;
+}
diff --git a/pkg/front_end/testcases/inference/property_get_toplevel.dart.weak.modular.expect b/pkg/front_end/testcases/inference/property_get_toplevel.dart.weak.modular.expect
new file mode 100644
index 0000000..4c93980
--- /dev/null
+++ b/pkg/front_end/testcases/inference/property_get_toplevel.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field core::int* field = 0;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  get getter() → core::int*
+    return 0;
+  method function() → core::int*
+    return 0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C* c = new self::C::•();
+static field () →* core::int* function_ref = self::c.{self::C::function}{() →* core::int*};
+static field core::List<() →* core::int*>* function_ref_list = <() →* core::int*>[self::c.{self::C::function}{() →* core::int*}];
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/property_set.dart.weak.modular.expect b/pkg/front_end/testcases/inference/property_set.dart.weak.modular.expect
new file mode 100644
index 0000000..c2feed8
--- /dev/null
+++ b/pkg/front_end/testcases/inference/property_set.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field core::List<self::A::T*>* x = null;
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  set y(covariant-by-class core::List<self::A::T*>* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  self::A<core::int*>* a_int = new self::A::•<core::int*>();
+  self::A<core::Object*>* a_object = new self::A::•<core::Object*>();
+  self::A<dynamic>* a_dynamic = new self::A::•<dynamic>();
+  core::List<core::int*>* x_int = a_int.{self::A::x} = <core::int*>[0];
+  core::List<core::int*>* y_int = a_int.{self::A::y} = <core::int*>[0];
+  core::List<core::Object*>* x_object = a_object.{self::A::x} = <core::Object*>[0];
+  core::List<core::Object*>* y_object = a_object.{self::A::y} = <core::Object*>[0];
+  core::List<dynamic>* x_dynamic = a_dynamic.{self::A::x} = <dynamic>[0];
+  core::List<dynamic>* y_dynamic = a_dynamic.{self::A::y} = <dynamic>[0];
+  core::List<core::int*>* x_int_explicit = a_int.{self::A::x} = <core::int*>[0];
+  core::List<core::int*>* y_int_explicit = a_int.{self::A::y} = <core::int*>[0];
+  core::List<core::int*>* x_object_explicit = a_object.{self::A::x} = <core::int*>[0];
+  core::List<core::int*>* y_object_explicit = a_object.{self::A::y} = <core::int*>[0];
+  core::List<core::int*>* x_dynamic_explicit = a_dynamic.{self::A::x} = <core::int*>[0];
+  core::List<core::int*>* y_dynamic_explicit = a_dynamic.{self::A::y} = <core::int*>[0];
+  core::List<core::int*>* x_int_downward = a_int.{self::A::x} = <core::int*>[0];
+  core::List<core::int*>* y_int_downward = a_int.{self::A::y} = <core::int*>[0];
+  core::List<core::int*>* x_object_downward = (a_object.{self::A::x} = <core::Object*>[0]) as{TypeError} core::List<core::int*>*;
+  core::List<core::int*>* y_object_downward = (a_object.{self::A::y} = <core::Object*>[0]) as{TypeError} core::List<core::int*>*;
+  core::List<core::int*>* x_dynamic_downward = (a_dynamic.{self::A::x} = <dynamic>[0]) as{TypeError} core::List<core::int*>*;
+  core::List<core::int*>* y_dynamic_downward = (a_dynamic.{self::A::y} = <dynamic>[0]) as{TypeError} core::List<core::int*>*;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/property_set_bad_setter.dart.weak.modular.expect b/pkg/front_end/testcases/inference/property_set_bad_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..3e05504
--- /dev/null
+++ b/pkg/front_end/testcases/inference/property_set_bad_setter.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/property_set_bad_setter.dart:9:13: Error: A setter should have exactly one formal parameter.
+//   void set x() {}
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  set x(dynamic #synthetic) → void {
+    invalid-expression "pkg/front_end/testcases/inference/property_set_bad_setter.dart:9:13: Error: A setter should have exactly one formal parameter.
+  void set x() {}
+            ^";
+    {}
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f(self::A* a) → void {
+  core::int* x = a.{self::A::x} = 0;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/recursive_generic_function.dart.weak.modular.expect b/pkg/front_end/testcases/inference/recursive_generic_function.dart.weak.modular.expect
new file mode 100644
index 0000000..d617cd4
--- /dev/null
+++ b/pkg/front_end/testcases/inference/recursive_generic_function.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method _mergeSort<T extends core::Object* = dynamic>((self::_mergeSort::T*) →* self::_mergeSort::T* list, (self::_mergeSort::T*, self::_mergeSort::T*) →* core::int* compare, (self::_mergeSort::T*) →* self::_mergeSort::T* target) → void {
+  self::_mergeSort<self::_mergeSort::T*>(list, compare, target);
+  self::_mergeSort<self::_mergeSort::T*>(list, compare, list);
+  self::_mergeSort<self::_mergeSort::T*>(target, compare, target);
+  self::_mergeSort<self::_mergeSort::T*>(target, compare, list);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/reference_to_typedef.dart.weak.modular.expect b/pkg/front_end/testcases/inference/reference_to_typedef.dart.weak.modular.expect
new file mode 100644
index 0000000..1c7e0ba
--- /dev/null
+++ b/pkg/front_end/testcases/inference/reference_to_typedef.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F = () →* void;
+static final field core::Type* x = #C1;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = TypeLiteralConstant(() →* void)
+}
diff --git a/pkg/front_end/testcases/inference/refine_binary_expression_type_type_parameter_t_double.dart.weak.modular.expect b/pkg/front_end/testcases/inference/refine_binary_expression_type_type_parameter_t_double.dart.weak.modular.expect
new file mode 100644
index 0000000..a3cae75
--- /dev/null
+++ b/pkg/front_end/testcases/inference/refine_binary_expression_type_type_parameter_t_double.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::num*> extends core::Object {
+  covariant-by-class field self::C::T* a = null;
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method op(core::double* b) → void {
+    core::double* r1 = this.{self::C::a}{self::C::T*}.{core::num::+}(b){(core::num*) →* core::num*} as{TypeError} core::double*;
+    core::double* r2 = this.{self::C::a}{self::C::T*}.{core::num::-}(b){(core::num*) →* core::num*} as{TypeError} core::double*;
+    core::double* r3 = this.{self::C::a}{self::C::T*}.{core::num::*}(b){(core::num*) →* core::num*} as{TypeError} core::double*;
+    core::double* r4 = this.{self::C::a}{self::C::T*}.{core::num::/}(b){(core::num*) →* core::double*};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/refine_binary_expression_type_type_parameter_t_int.dart.weak.modular.expect b/pkg/front_end/testcases/inference/refine_binary_expression_type_type_parameter_t_int.dart.weak.modular.expect
new file mode 100644
index 0000000..24e9591
--- /dev/null
+++ b/pkg/front_end/testcases/inference/refine_binary_expression_type_type_parameter_t_int.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::num*> extends core::Object {
+  covariant-by-class field self::C::T* a = null;
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method op(core::int* b) → void {
+    self::C::T* r1 = this.{self::C::a}{self::C::T*}.{core::num::+}(b){(core::num*) →* core::num*} as{TypeError} self::C::T*;
+    self::C::T* r2 = this.{self::C::a}{self::C::T*}.{core::num::-}(b){(core::num*) →* core::num*} as{TypeError} self::C::T*;
+    self::C::T* r3 = this.{self::C::a}{self::C::T*}.{core::num::*}(b){(core::num*) →* core::num*} as{TypeError} self::C::T*;
+  }
+  method opEq(core::int* b) → void {
+    this.{self::C::a} = this.{self::C::a}{self::C::T*}.{core::num::+}(b){(core::num*) →* core::num*} as{TypeError} self::C::T*;
+    this.{self::C::a} = this.{self::C::a}{self::C::T*}.{core::num::-}(b){(core::num*) →* core::num*} as{TypeError} self::C::T*;
+    this.{self::C::a} = this.{self::C::a}{self::C::T*}.{core::num::*}(b){(core::num*) →* core::num*} as{TypeError} self::C::T*;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/refine_binary_expression_type_type_parameter_t_t.dart.weak.modular.expect b/pkg/front_end/testcases/inference/refine_binary_expression_type_type_parameter_t_t.dart.weak.modular.expect
new file mode 100644
index 0000000..88143e7
--- /dev/null
+++ b/pkg/front_end/testcases/inference/refine_binary_expression_type_type_parameter_t_t.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::num*> extends core::Object {
+  covariant-by-class field self::C::T* a = null;
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method op(covariant-by-class self::C::T* b) → void {
+    self::C::T* r1 = this.{self::C::a}{self::C::T*}.{core::num::+}(b){(core::num*) →* core::num*} as{TypeError} self::C::T*;
+    self::C::T* r2 = this.{self::C::a}{self::C::T*}.{core::num::-}(b){(core::num*) →* core::num*} as{TypeError} self::C::T*;
+    self::C::T* r3 = this.{self::C::a}{self::C::T*}.{core::num::*}(b){(core::num*) →* core::num*} as{TypeError} self::C::T*;
+  }
+  method opEq(covariant-by-class self::C::T* b) → void {
+    this.{self::C::a} = this.{self::C::a}{self::C::T*}.{core::num::+}(b){(core::num*) →* core::num*} as{TypeError} self::C::T*;
+    this.{self::C::a} = this.{self::C::a}{self::C::T*}.{core::num::-}(b){(core::num*) →* core::num*} as{TypeError} self::C::T*;
+    this.{self::C::a} = this.{self::C::a}{self::C::T*}.{core::num::*}(b){(core::num*) →* core::num*} as{TypeError} self::C::T*;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/setter_return_type.dart.weak.modular.expect b/pkg/front_end/testcases/inference/setter_return_type.dart.weak.modular.expect
new file mode 100644
index 0000000..b816e0d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/setter_return_type.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  set x(core::int* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  set x(core::int* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C implements self::I {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  set x(core::int* value) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/simple_literal_bool.dart.weak.modular.expect b/pkg/front_end/testcases/inference/simple_literal_bool.dart.weak.modular.expect
new file mode 100644
index 0000000..da6bc88
--- /dev/null
+++ b/pkg/front_end/testcases/inference/simple_literal_bool.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::bool* a = true;
+static method main() → dynamic {
+  core::bool* b = false;
+}
diff --git a/pkg/front_end/testcases/inference/simple_literal_double.dart.weak.modular.expect b/pkg/front_end/testcases/inference/simple_literal_double.dart.weak.modular.expect
new file mode 100644
index 0000000..ce86f42
--- /dev/null
+++ b/pkg/front_end/testcases/inference/simple_literal_double.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::double* a = 1.2;
+static method main() → dynamic {
+  core::double* b = 3.4;
+}
diff --git a/pkg/front_end/testcases/inference/simple_literal_int.dart.weak.modular.expect b/pkg/front_end/testcases/inference/simple_literal_int.dart.weak.modular.expect
new file mode 100644
index 0000000..02faaca
--- /dev/null
+++ b/pkg/front_end/testcases/inference/simple_literal_int.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::int* a = 1;
+static method main() → dynamic {
+  core::int* b = 2;
+}
diff --git a/pkg/front_end/testcases/inference/simple_literal_null.dart.weak.modular.expect b/pkg/front_end/testcases/inference/simple_literal_null.dart.weak.modular.expect
new file mode 100644
index 0000000..8afbb2c
--- /dev/null
+++ b/pkg/front_end/testcases/inference/simple_literal_null.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library test;
+import self as self;
+
+static field dynamic a = null;
+static method main() → dynamic {
+  dynamic b = null;
+}
diff --git a/pkg/front_end/testcases/inference/static_method_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/inference/static_method_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..b89fa7d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/static_method_tear_off.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  static method f(core::String* s) → core::int*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field (core::String*) →* core::int* v = #C1;
+static method main() → dynamic {
+  #C1;
+}
+
+constants  {
+  #C1 = static-tearoff self::C::f
+}
diff --git a/pkg/front_end/testcases/inference/string_literal.dart.weak.modular.expect b/pkg/front_end/testcases/inference/string_literal.dart.weak.modular.expect
new file mode 100644
index 0000000..c59623a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/string_literal.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::int* x = 1;
+static field core::String* a = "aaa";
+static field core::String* b = "b ${self::x} bb";
+static field core::String* c = "c ${self::x} ccccc";
+static method main() → dynamic {
+  core::int* x = 1;
+  core::String* a = "aaa";
+  core::String* b = "b ${x} bb";
+  core::String* c = "c ${x} ccccc";
+}
diff --git a/pkg/front_end/testcases/inference/subexpressions_of_explicitly_typed_fields.dart.weak.modular.expect b/pkg/front_end/testcases/inference/subexpressions_of_explicitly_typed_fields.dart.weak.modular.expect
new file mode 100644
index 0000000..d1ef879
--- /dev/null
+++ b/pkg/front_end/testcases/inference/subexpressions_of_explicitly_typed_fields.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field core::List<core::num*>* x = <core::num*>[0];
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::List<core::num*>* y = <core::num*>[0];
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/super_index_set.dart.weak.modular.expect b/pkg/front_end/testcases/inference/super_index_set.dart.weak.modular.expect
new file mode 100644
index 0000000..8b870ab
--- /dev/null
+++ b/pkg/front_end/testcases/inference/super_index_set.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  operator []=(core::int* x, core::String* y) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  operator []=(core::Object* x, core::Object* y) → void {}
+  method h() → void {
+    super.{self::B::[]=}(self::f<core::int*>(), self::f<core::String*>());
+  }
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/super_index_set_substitution.dart.weak.modular.expect b/pkg/front_end/testcases/inference/super_index_set_substitution.dart.weak.modular.expect
new file mode 100644
index 0000000..e59a920
--- /dev/null
+++ b/pkg/front_end/testcases/inference/super_index_set_substitution.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class B<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  operator []=(covariant-by-class core::Map<core::int*, self::B::T*>* x, covariant-by-class core::List<self::B::T*>* y) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<U extends core::Object* = dynamic> extends self::B<asy::Future<self::C::U*>*> {
+  synthetic constructor •() → self::C<self::C::U*>*
+    : super self::B::•()
+    ;
+  operator []=(covariant-by-class core::Object* x, covariant-by-class core::Object* y) → void {}
+  method h() → void {
+    super.{self::B::[]=}(self::f<core::Map<core::int*, asy::Future<self::C::U*>*>*>(), self::f<core::List<asy::Future<self::C::U*>*>*>());
+  }
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/super_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/inference/super_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..8e244eb
--- /dev/null
+++ b/pkg/front_end/testcases/inference/super_initializer.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends self::B {
+  constructor •() → self::C*
+    : super self::B::•(self::f<core::int*>())
+    ;
+}
+class B extends core::Object {
+  constructor •(core::int* x) → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/super_initializer_substitution.dart.weak.modular.expect b/pkg/front_end/testcases/inference/super_initializer_substitution.dart.weak.modular.expect
new file mode 100644
index 0000000..1d91491
--- /dev/null
+++ b/pkg/front_end/testcases/inference/super_initializer_substitution.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(self::B::T* t) → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<U extends core::Object* = dynamic> extends self::B<core::List<self::C::U*>*> {
+  constructor •() → self::C<self::C::U*>*
+    : super self::B::•(self::f<core::List<self::C::U*>*>())
+    ;
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/super_method_invocation.dart.weak.modular.expect b/pkg/front_end/testcases/inference/super_method_invocation.dart.weak.modular.expect
new file mode 100644
index 0000000..f51320a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/super_method_invocation.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f() → core::int*
+    return 0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method g() → void {
+    core::int* x = super.{self::C::f}();
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/super_method_invocation_substitution.dart.weak.modular.expect b/pkg/front_end/testcases/inference/super_method_invocation_substitution.dart.weak.modular.expect
new file mode 100644
index 0000000..940c20e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/super_method_invocation_substitution.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class D<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E<T extends core::Object* = dynamic> extends self::D<self::E::T*> {
+  synthetic constructor •() → self::E<self::E::T*>*
+    : super self::D::•()
+    ;
+}
+class B<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  method g(covariant-by-class self::E<self::B::T*>* x) → self::D<self::B::T*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<U extends core::Object* = dynamic> extends self::B<asy::Future<self::C::U*>*> {
+  synthetic constructor •() → self::C<self::C::U*>*
+    : super self::B::•()
+    ;
+  method g(covariant-by-class core::Object* x) → self::E<asy::Future<self::C::U*>*>*
+    return null;
+  method h() → void {
+    self::D<asy::Future<self::C::U*>*>* x = super.{self::B::g}(self::f<self::E<asy::Future<self::C::U*>*>*>());
+  }
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/super_property_get.dart.weak.modular.expect b/pkg/front_end/testcases/inference/super_property_get.dart.weak.modular.expect
new file mode 100644
index 0000000..c9a8df8
--- /dev/null
+++ b/pkg/front_end/testcases/inference/super_property_get.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field core::int* x = 0;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method g() → void {
+    core::int* y = super.{self::C::x};
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/super_property_get_invoke_function_typed.dart.weak.modular.expect b/pkg/front_end/testcases/inference/super_property_get_invoke_function_typed.dart.weak.modular.expect
new file mode 100644
index 0000000..23c68ac
--- /dev/null
+++ b/pkg/front_end/testcases/inference/super_property_get_invoke_function_typed.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field () →* core::int* f = () → core::int* => 0;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method g() → void {
+    core::int* y = super.{self::C::f}(){() →* core::int*};
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/super_property_get_invoke_implicit_call.dart.weak.modular.expect b/pkg/front_end/testcases/inference/super_property_get_invoke_implicit_call.dart.weak.modular.expect
new file mode 100644
index 0000000..f32675f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/super_property_get_invoke_implicit_call.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class CallableClass extends core::Object {
+  synthetic constructor •() → self::CallableClass*
+    : super core::Object::•()
+    ;
+  method call() → core::int*
+    return 0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  field self::CallableClass* f = new self::CallableClass::•();
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method g() → void {
+    core::int* y = super.{self::C::f}.{self::CallableClass::call}(){() →* core::int*};
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/super_property_get_substitution.dart.weak.modular.expect b/pkg/front_end/testcases/inference/super_property_get_substitution.dart.weak.modular.expect
new file mode 100644
index 0000000..752cdaf
--- /dev/null
+++ b/pkg/front_end/testcases/inference/super_property_get_substitution.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class D<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E<T extends core::Object* = dynamic> extends self::D<self::E::T*> {
+  synthetic constructor •() → self::E<self::E::T*>*
+    : super self::D::•()
+    ;
+}
+class B<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::D<self::B::T*>* x = null;
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<U extends core::Object* = dynamic> extends self::B<asy::Future<self::C::U*>*> {
+  synthetic constructor •() → self::C<self::C::U*>*
+    : super self::B::•()
+    ;
+  get x() → self::E<asy::Future<self::C::U*>*>*
+    return null;
+  set x(covariant-by-class core::Object* x) → void {}
+  method g() → void {
+    self::D<asy::Future<self::C::U*>*>* y = super.{self::B::x};
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/super_property_get_tearoff.dart.weak.modular.expect b/pkg/front_end/testcases/inference/super_property_get_tearoff.dart.weak.modular.expect
new file mode 100644
index 0000000..5f7255e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/super_property_get_tearoff.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f() → core::int*
+    return 0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method g() → void {
+    () →* core::int* y = super.{self::C::f};
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/super_property_set_substitution.dart.weak.modular.expect b/pkg/front_end/testcases/inference/super_property_set_substitution.dart.weak.modular.expect
new file mode 100644
index 0000000..2b490e3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/super_property_set_substitution.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class D<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E<T extends core::Object* = dynamic> extends self::D<self::E::T*> {
+  synthetic constructor •() → self::E<self::E::T*>*
+    : super self::D::•()
+    ;
+}
+class B<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::D<self::B::T*>* x = null;
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<U extends core::Object* = dynamic> extends self::B<asy::Future<self::C::U*>*> {
+  synthetic constructor •() → self::C<self::C::U*>*
+    : super self::B::•()
+    ;
+  get x() → self::E<asy::Future<self::C::U*>*>*
+    return null;
+  set x(covariant-by-class core::Object* x) → void {}
+  method g() → void {
+    super.{self::B::x} = self::f<self::D<asy::Future<self::C::U*>*>*>();
+  }
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/switch_continue.dart.weak.modular.expect b/pkg/front_end/testcases/inference/switch_continue.dart.weak.modular.expect
new file mode 100644
index 0000000..64406d0
--- /dev/null
+++ b/pkg/front_end/testcases/inference/switch_continue.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test(core::int* x, () →* void f) → void {
+  #L1:
+  switch(x) {
+    #L2:
+    case #C1:
+      {
+        f(){() →* void};
+        continue #L3;
+      }
+    #L3:
+    case #C2:
+      {
+        f(){() →* void};
+        break #L1;
+      }
+  }
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+  #C2 = 1
+}
diff --git a/pkg/front_end/testcases/inference/symbol_literal.dart.weak.modular.expect b/pkg/front_end/testcases/inference/symbol_literal.dart.weak.modular.expect
new file mode 100644
index 0000000..1a4d6a8
--- /dev/null
+++ b/pkg/front_end/testcases/inference/symbol_literal.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  core::Symbol* x = #C1;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #foo
+}
diff --git a/pkg/front_end/testcases/inference/this_reference.dart.weak.modular.expect b/pkg/front_end/testcases/inference/this_reference.dart.weak.modular.expect
new file mode 100644
index 0000000..06fb537
--- /dev/null
+++ b/pkg/front_end/testcases/inference/this_reference.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method f() → void {
+    self::C<self::C::T*>* x = this;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/top_level_return_and_yield.dart.weak.modular.expect b/pkg/front_end/testcases/inference/top_level_return_and_yield.dart.weak.modular.expect
new file mode 100644
index 0000000..3ca6230
--- /dev/null
+++ b/pkg/front_end/testcases/inference/top_level_return_and_yield.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/top_level_return_and_yield.dart:18:36: Error: A value of type 'Future<dynamic Function(dynamic)>' can't be assigned to a variable of type 'FutureOr<int Function(int)>'.
+//  - 'Future' is from 'dart:async'.
+//   return /*@ returnType=dynamic */ (/*@ type=dynamic */ x) => x;
+//                                    ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+typedef IntToInt = (core::int*) →* core::int*;
+static method a() → (core::int*) →* core::int* {
+  return (core::int* x) → core::int* => x;
+}
+static method b() → asy::Future<(core::int*) →* core::int*>* async {
+  return invalid-expression "pkg/front_end/testcases/inference/top_level_return_and_yield.dart:18:36: Error: A value of type 'Future<dynamic Function(dynamic)>' can't be assigned to a variable of type 'FutureOr<int Function(int)>'.
+ - 'Future' is from 'dart:async'.
+  return /*@ returnType=dynamic */ (/*@ type=dynamic */ x) => x;
+                                   ^" in ((dynamic x) → dynamic => x) as{TypeError} FutureOr<(core::int*) →* core::int*>*;
+}
+static method c() → core::Iterable<(core::int*) →* core::int*>* sync* {
+  yield(core::int* x) → core::int* => x;
+}
+static method d() → core::Iterable<(core::int*) →* core::int*>* sync* {
+  yield*<(core::int*) →* core::int*>[(core::int* x) → core::int* => x];
+}
+static method e() → asy::Stream<(core::int*) →* core::int*>* async* {
+  yield(core::int* x) → core::int* => x;
+}
+static method f() → asy::Stream<(core::int*) →* core::int*>* async* {
+  yield* asy::Stream::fromIterable<(core::int*) →* core::int*>(<(core::int*) →* core::int*>[(core::int* x) → core::int* => x]);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/toplevel_inference_toplevel_var.dart.weak.modular.expect b/pkg/front_end/testcases/inference/toplevel_inference_toplevel_var.dart.weak.modular.expect
new file mode 100644
index 0000000..9ab8405
--- /dev/null
+++ b/pkg/front_end/testcases/inference/toplevel_inference_toplevel_var.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::int* i = 0;
+static method main() → dynamic {
+  core::int* j = self::i;
+}
diff --git a/pkg/front_end/testcases/inference/try_catch.dart.weak.modular.expect b/pkg/front_end/testcases/inference/try_catch.dart.weak.modular.expect
new file mode 100644
index 0000000..086e91e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/try_catch.dart.weak.modular.expect
@@ -0,0 +1,70 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E extends core::Object {
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test(() →* void f) → void {
+  try {
+    core::int* x = 0;
+    f(){() →* void};
+  }
+  on self::C* catch(no-exception-var) {
+    core::int* x = 0;
+  }
+  on self::D* catch(final self::D* x) {
+    self::D* x2 = x;
+  }
+  on self::E* catch(final self::E* x, final core::StackTrace* y) {
+    self::E* x2 = x;
+    core::StackTrace* y2 = y;
+  }
+  on dynamic catch(final dynamic x, final core::StackTrace* y) {
+    dynamic x2 = x;
+    core::StackTrace* y2 = y;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/try_catch_finally.dart.weak.modular.expect b/pkg/front_end/testcases/inference/try_catch_finally.dart.weak.modular.expect
new file mode 100644
index 0000000..62db44d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/try_catch_finally.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E extends core::Object {
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test(() →* void f) → void {
+  try
+    try {
+      core::int* x = 0;
+      f(){() →* void};
+    }
+    on self::C* catch(no-exception-var) {
+      core::int* x = 0;
+    }
+    on self::D* catch(final self::D* x) {
+      self::D* x2 = x;
+    }
+    on self::E* catch(final self::E* x, final core::StackTrace* y) {
+      self::E* x2 = x;
+      core::StackTrace* y2 = y;
+    }
+    on dynamic catch(final dynamic x, final core::StackTrace* y) {
+      dynamic x2 = x;
+      core::StackTrace* y2 = y;
+    }
+  finally {
+    core::int* x = 0;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/try_catch_promotion.dart.weak.modular.expect b/pkg/front_end/testcases/inference/try_catch_promotion.dart.weak.modular.expect
new file mode 100644
index 0000000..0f37b73
--- /dev/null
+++ b/pkg/front_end/testcases/inference/try_catch_promotion.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+}
+class E extends core::StackTrace {
+  synthetic constructor •() → self::E*
+    : super core::StackTrace::•()
+    ;
+  abstract member-signature method toString() → core::String*; -> core::StackTrace::toString
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test(() →* void f) → void {
+  try {
+    f(){() →* void};
+  }
+  on self::C* catch(final self::C* x, final core::StackTrace* y) {
+    self::C* x1 = x;
+    core::StackTrace* y1 = y;
+    if(x is self::D*) {
+      self::D* x2 = x{self::D*};
+    }
+    if(y is self::E*) {
+      self::E* y2 = y{self::E*};
+    }
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/try_finally.dart.weak.modular.expect b/pkg/front_end/testcases/inference/try_finally.dart.weak.modular.expect
new file mode 100644
index 0000000..f52f88a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/try_finally.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method test(() →* void f) → void {
+  try {
+    core::int* x = 0;
+    f(){() →* void};
+  }
+  finally {
+    core::int* x = 0;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/type_cast.dart.weak.modular.expect b/pkg/front_end/testcases/inference/type_cast.dart.weak.modular.expect
new file mode 100644
index 0000000..4d12ac0
--- /dev/null
+++ b/pkg/front_end/testcases/inference/type_cast.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::Object* = dynamic> extends self::A<self::B::T*> {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super self::A::•()
+    ;
+  method foo() → dynamic {}
+}
+static field self::A<core::num*>* a = new self::B::•<core::int*>();
+static field self::B<core::int*>* b = self::a as self::B<core::int*>*;
+static method main() → dynamic {
+  self::A<core::num*>* a = new self::B::•<core::int*>();
+  self::B<core::int*>* b = a as self::B<core::int*>*;
+}
diff --git a/pkg/front_end/testcases/inference/type_promotion_ignores_local_functions.dart.weak.modular.expect b/pkg/front_end/testcases/inference/type_promotion_ignores_local_functions.dart.weak.modular.expect
new file mode 100644
index 0000000..6269884
--- /dev/null
+++ b/pkg/front_end/testcases/inference/type_promotion_ignores_local_functions.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef FunctionReturningInt = () →* core::int*;
+static method main() → dynamic {
+  function f() → core::num*
+    return 0;
+  if(f is () →* core::int*) {
+    f;
+  }
+}
diff --git a/pkg/front_end/testcases/inference/type_promotion_not_and_not.dart.weak.modular.expect b/pkg/front_end/testcases/inference/type_promotion_not_and_not.dart.weak.modular.expect
new file mode 100644
index 0000000..ca793f8
--- /dev/null
+++ b/pkg/front_end/testcases/inference/type_promotion_not_and_not.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method f(core::Object* x) → void {
+  if(!(x is core::int*) && !(x is core::String*)) {
+    core::print(x);
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/type_promotion_simple.dart.weak.modular.expect b/pkg/front_end/testcases/inference/type_promotion_simple.dart.weak.modular.expect
new file mode 100644
index 0000000..4e2acb6
--- /dev/null
+++ b/pkg/front_end/testcases/inference/type_promotion_simple.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::num* n = null;
+  if(n is core::int*) {
+    core::int* i = n{core::int*};
+  }
+}
diff --git a/pkg/front_end/testcases/inference/type_promotion_stopped_by_access_in_a_closure.dart.weak.modular.expect b/pkg/front_end/testcases/inference/type_promotion_stopped_by_access_in_a_closure.dart.weak.modular.expect
new file mode 100644
index 0000000..db5f0ef
--- /dev/null
+++ b/pkg/front_end/testcases/inference/type_promotion_stopped_by_access_in_a_closure.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::num* n = null;
+  if(n is core::int*) {
+    core::num* i = n;
+    () → Null {
+      n;
+    };
+  }
+  n = null;
+}
diff --git a/pkg/front_end/testcases/inference/type_promotion_stopped_by_assignment_in_scope.dart.weak.modular.expect b/pkg/front_end/testcases/inference/type_promotion_stopped_by_assignment_in_scope.dart.weak.modular.expect
new file mode 100644
index 0000000..ca4ba99
--- /dev/null
+++ b/pkg/front_end/testcases/inference/type_promotion_stopped_by_assignment_in_scope.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::num* n = null;
+  if(n is core::int*) {
+    core::num* i = n;
+    n = null;
+  }
+}
diff --git a/pkg/front_end/testcases/inference/type_promotion_stopped_by_mutation_in_a_closure.dart.weak.modular.expect b/pkg/front_end/testcases/inference/type_promotion_stopped_by_mutation_in_a_closure.dart.weak.modular.expect
new file mode 100644
index 0000000..d377034
--- /dev/null
+++ b/pkg/front_end/testcases/inference/type_promotion_stopped_by_mutation_in_a_closure.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::num* n = null;
+  if(n is core::int*) {
+    core::num* i = n;
+  }
+  () → Null {
+    n = null;
+  };
+}
diff --git a/pkg/front_end/testcases/inference/unresolved_super.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unresolved_super.dart.weak.modular.expect
new file mode 100644
index 0000000..e3758d3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unresolved_super.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/unresolved_super.dart:16:37: Error: Superclass has no method named '[]='.
+//     var /*@type=dynamic*/ v5 = super[0] = /*@typeArgs=dynamic*/ f();
+//                                     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method test() → void {
+    dynamic v5 = let final core::int* #t1 = 0 in let final dynamic #t2 = self::f<dynamic>() in let final void #t3 = invalid-expression "pkg/front_end/testcases/inference/unresolved_super.dart:16:37: Error: Superclass has no method named '[]='.
+    var /*@type=dynamic*/ v5 = super[0] = /*@typeArgs=dynamic*/ f();
+                                    ^" in #t2;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_closure_call.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_closure_call.dart.weak.modular.expect
new file mode 100644
index 0000000..4c0ed46
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_closure_call.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::double* v = ((dynamic x) → core::double* => 1.0)(() → core::int* {
+    return 1;
+  }){(dynamic) →* core::double*};
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_constructor_call_explicit_dynamic_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_constructor_call_explicit_dynamic_param.dart.weak.modular.expect
new file mode 100644
index 0000000..e65f4933
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_constructor_call_explicit_dynamic_param.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(() →* self::C::T* x) → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C<dynamic>* v = new self::C::•<dynamic>(() → core::int* {
+  return 1;
+});
+static method main() → dynamic {
+  self::v;
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_constructor_call_explicit_type_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_constructor_call_explicit_type_param.dart.weak.modular.expect
new file mode 100644
index 0000000..156c565
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_constructor_call_explicit_type_param.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(() →* self::C::T* x) → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C<core::int*>* v = new self::C::•<core::int*>(() → core::int* {
+  return 1;
+});
+static method main() → dynamic {
+  self::v;
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_constructor_call_implicit_type_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_constructor_call_implicit_type_param.dart.weak.modular.expect
new file mode 100644
index 0000000..0e7282f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_constructor_call_implicit_type_param.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(() →* self::C::T* x) → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C<core::int*>* v = new self::C::•<core::int*>(() → core::int* {
+    return 1;
+  });
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_constructor_call_no_type_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_constructor_call_no_type_param.dart.weak.modular.expect
new file mode 100644
index 0000000..939c023
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_constructor_call_no_type_param.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  constructor •(() →* dynamic x) → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C* v = new self::C::•(() → core::int* {
+  return 1;
+});
+static method main() → dynamic {
+  self::v;
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_dynamic_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_dynamic_param.dart.weak.modular.expect
new file mode 100644
index 0000000..2ac59fb
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_dynamic_param.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<dynamic>* v = self::f<dynamic>(() → core::int* {
+  return 1;
+});
+static method f<T extends core::Object* = dynamic>(() →* self::f::T* g) → core::List<self::f::T*>*
+  return <self::f::T*>[g(){() →* self::f::T*}];
+static method main() → dynamic {
+  self::v;
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_dynamic_param_via_expr1.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_dynamic_param_via_expr1.dart.weak.modular.expect
new file mode 100644
index 0000000..14f27fa
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_dynamic_param_via_expr1.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_dynamic_param_via_expr1.dart:9:11: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+// var v = (f<dynamic>)/*@typeArgs=int**/(/*@returnType=int**/() {
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field core::List<core::int*>* v = #C1<core::int*>(() → core::int* {
+  return 1;
+}){(() →* core::int*) →* core::List<core::int*>*};
+static method f<T extends core::Object* = dynamic>(() →* self::f::T* g) → core::List<self::f::T*>*
+  return <self::f::T*>[g(){() →* self::f::T*}];
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::f
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_dynamic_param_via_expr2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_dynamic_param_via_expr2.dart.weak.modular.expect
new file mode 100644
index 0000000..cf406c1
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_dynamic_param_via_expr2.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<dynamic>* v = #C1<dynamic>(() → core::int* {
+  return 1;
+}){(() →* dynamic) →* core::List<dynamic>*};
+static method f<T extends core::Object* = dynamic>(() →* self::f::T* g) → core::List<self::f::T*>*
+  return <self::f::T*>[g(){() →* self::f::T*}];
+static method main() → dynamic {
+  self::v;
+}
+
+constants  {
+  #C1 = static-tearoff self::f
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_type_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_type_param.dart.weak.modular.expect
new file mode 100644
index 0000000..06e337e
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_type_param.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<core::int*>* v = self::f<core::int*>(() → core::int* {
+  return 1;
+});
+static method f<T extends core::Object* = dynamic>(() →* self::f::T* g) → core::List<self::f::T*>*
+  return <self::f::T*>[g(){() →* self::f::T*}];
+static method main() → dynamic {
+  self::v;
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_type_param_via_expr1.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_type_param_via_expr1.dart.weak.modular.expect
new file mode 100644
index 0000000..1d604ce
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_type_param_via_expr1.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_type_param_via_expr1.dart:9:11: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+// var v = (f<int>)/*@typeArgs=int**/(/*@returnType=int**/() {
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field core::List<core::int*>* v = #C1<core::int*>(() → core::int* {
+  return 1;
+}){(() →* core::int*) →* core::List<core::int*>*};
+static method f<T extends core::Object* = dynamic>(() →* self::f::T* g) → core::List<self::f::T*>*
+  return <self::f::T*>[g(){() →* self::f::T*}];
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::f
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_type_param_via_expr2.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_type_param_via_expr2.dart.weak.modular.expect
new file mode 100644
index 0000000..26fdda1
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_explicit_type_param_via_expr2.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<core::int*>* v = #C1<core::int*>(() → core::int* {
+  return 1;
+}){(() →* core::int*) →* core::List<core::int*>*};
+static method f<T extends core::Object* = dynamic>(() →* self::f::T* g) → core::List<self::f::T*>*
+  return <self::f::T*>[g(){() →* self::f::T*}];
+static method main() → dynamic {
+  self::v;
+}
+
+constants  {
+  #C1 = static-tearoff self::f
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_implicit_type_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_implicit_type_param.dart.weak.modular.expect
new file mode 100644
index 0000000..720cf75
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_implicit_type_param.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::List<core::int*>* v = self::f<core::int*>(() → core::int* {
+    return 1;
+  });
+}
+static method f<T extends core::Object* = dynamic>(() →* self::f::T* g) → core::List<self::f::T*>*
+  return <self::f::T*>[g(){() →* self::f::T*}];
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_implicit_type_param_via_expr.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_implicit_type_param_via_expr.dart.weak.modular.expect
new file mode 100644
index 0000000..7def91f
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_implicit_type_param_via_expr.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::List<core::int*>* v = #C1<core::int*>(() → core::int* {
+    return 1;
+  }){(() →* core::int*) →* core::List<core::int*>*};
+}
+static method f<T extends core::Object* = dynamic>(() →* self::f::T* g) → core::List<self::f::T*>*
+  return <self::f::T*>[g(){() →* self::f::T*}];
+
+constants  {
+  #C1 = static-tearoff self::f
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_no_type_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_no_type_param.dart.weak.modular.expect
new file mode 100644
index 0000000..715a3f3
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_no_type_param.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::double* v = self::f(() → core::int* {
+    return 1;
+  });
+}
+static method f(dynamic x) → core::double*
+  return 1.0;
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_no_type_param_via_expr.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_no_type_param_via_expr.dart.weak.modular.expect
new file mode 100644
index 0000000..d720962
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_function_call_no_type_param_via_expr.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::double* v = #C1(() → core::int* {
+    return 1;
+  }){(dynamic) →* core::double*};
+}
+static method f(dynamic x) → core::double*
+  return 1.0;
+
+constants  {
+  #C1 = static-tearoff self::f
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_list_dynamic.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_list_dynamic.dart.weak.modular.expect
new file mode 100644
index 0000000..bc2b33d
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_list_dynamic.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::List<dynamic>* v = <dynamic>[() → core::int* {
+    return 1;
+  }];
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_list_typed.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_list_typed.dart.weak.modular.expect
new file mode 100644
index 0000000..b747c51
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_list_typed.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F = () →* core::int*;
+static method main() → dynamic {
+  core::List<() →* core::int*>* v = <() →* core::int*>[() → core::int* {
+    return 1;
+  }];
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_list_untyped.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_list_untyped.dart.weak.modular.expect
new file mode 100644
index 0000000..5b2da50
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_list_untyped.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::List<() →* core::int*>* v = <() →* core::int*>[() → core::int* {
+    return 1;
+  }];
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_map_dynamic.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_map_dynamic.dart.weak.modular.expect
new file mode 100644
index 0000000..07d95de
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_map_dynamic.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::Map<core::int*, dynamic>* v = <core::int*, dynamic>{1: () → core::int* {
+    return 1;
+  }};
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_map_typed.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_map_typed.dart.weak.modular.expect
new file mode 100644
index 0000000..7e2da76
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_map_typed.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F = () →* core::int*;
+static method main() → dynamic {
+  core::Map<core::int*, () →* core::int*>* v = <core::int*, () →* core::int*>{1: () → core::int* {
+    return 1;
+  }};
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_map_untyped.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_map_untyped.dart.weak.modular.expect
new file mode 100644
index 0000000..f2aa7b1
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_in_map_untyped.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::Map<core::int*, () →* core::int*>* v = <core::int*, () →* core::int*>{1: () → core::int* {
+    return 1;
+  }};
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_method_call_explicit_dynamic_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_method_call_explicit_dynamic_param.dart.weak.modular.expect
new file mode 100644
index 0000000..7011442a
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_method_call_explicit_dynamic_param.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f<T extends core::Object* = dynamic>(() →* self::C::f::T* g) → core::List<self::C::f::T*>*
+    return <self::C::f::T*>[g(){() →* self::C::f::T*}];
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::List<dynamic>* v = new self::C::•().{self::C::f}<dynamic>(() → core::int* {
+    return 1;
+  }){(() →* dynamic) →* core::List<dynamic>*};
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_method_call_explicit_type_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_method_call_explicit_type_param.dart.weak.modular.expect
new file mode 100644
index 0000000..3df5bcf
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_method_call_explicit_type_param.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f<T extends core::Object* = dynamic>(() →* self::C::f::T* g) → core::List<self::C::f::T*>*
+    return <self::C::f::T*>[g(){() →* self::C::f::T*}];
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::List<core::int*>* v = new self::C::•().{self::C::f}<core::int*>(() → core::int* {
+    return 1;
+  }){(() →* core::int*) →* core::List<core::int*>*};
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_method_call_implicit_type_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_method_call_implicit_type_param.dart.weak.modular.expect
new file mode 100644
index 0000000..3df5bcf
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_method_call_implicit_type_param.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f<T extends core::Object* = dynamic>(() →* self::C::f::T* g) → core::List<self::C::f::T*>*
+    return <self::C::f::T*>[g(){() →* self::C::f::T*}];
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::List<core::int*>* v = new self::C::•().{self::C::f}<core::int*>(() → core::int* {
+    return 1;
+  }){(() →* core::int*) →* core::List<core::int*>*};
+}
diff --git a/pkg/front_end/testcases/inference/unsafe_block_closure_inference_method_call_no_type_param.dart.weak.modular.expect b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_method_call_no_type_param.dart.weak.modular.expect
new file mode 100644
index 0000000..f00aa66
--- /dev/null
+++ b/pkg/front_end/testcases/inference/unsafe_block_closure_inference_method_call_no_type_param.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f(dynamic x) → core::double*
+    return 1.0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::double* v = new self::C::•().{self::C::f}(() → core::int* {
+  return 1;
+}){(dynamic) →* core::double*};
+static method main() → dynamic {
+  self::v;
+}
diff --git a/pkg/front_end/testcases/inference/void_return_type_subtypes_dynamic.dart.weak.modular.expect b/pkg/front_end/testcases/inference/void_return_type_subtypes_dynamic.dart.weak.modular.expect
new file mode 100644
index 0000000..751e547
--- /dev/null
+++ b/pkg/front_end/testcases/inference/void_return_type_subtypes_dynamic.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field dynamic x = self::run<dynamic>(#C1);
+static method run<T extends core::Object* = dynamic>(() →* self::run::T* f) → self::run::T* {
+  core::print("running");
+  self::run::T* t = f(){() →* self::run::T*};
+  core::print("done running");
+  return t;
+}
+static method printRunning() → void {
+  core::print("running");
+}
+static method main() → dynamic {
+  function printRunning() → void {
+    core::print("running");
+  }
+  dynamic x = self::run<dynamic>(printRunning);
+  void y = self::run<void>(printRunning);
+  x = 123;
+  x = "hi";
+  y = 123;
+  y = "hi";
+}
+
+constants  {
+  #C1 = static-tearoff self::printRunning
+}
diff --git a/pkg/front_end/testcases/inference_new/const_invocation.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/const_invocation.dart.weak.modular.expect
new file mode 100644
index 0000000..388292d
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/const_invocation.dart.weak.modular.expect
@@ -0,0 +1,72 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant U extends core::Object* = dynamic, V extends core::Object* = dynamic> = (U*) →* V*;
+class Foo<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Foo<self::Foo::T*>*
+    : super core::Object::•()
+    ;
+  get v1() → self::Bar<self::Foo::T*>*
+    return #C1;
+  get v2() → self::Bar<core::List<self::Foo::T*>*>*
+    return #C2;
+  get v3() → self::Bar<(self::Foo::T*) →* self::Foo::T*>*
+    return #C3;
+  get v4() → self::Bar<((self::Foo::T*) →* self::Foo::T*) →* self::Foo::T*>*
+    return #C4;
+  get v5() → core::List<self::Foo::T*>*
+    return #C5;
+  get v6() → core::List<(self::Foo::T*) →* self::Foo::T*>*
+    return #C6;
+  get v7() → core::Map<self::Foo::T*, self::Foo::T*>*
+    return #C7;
+  get v8() → core::Map<(self::Foo::T*) →* self::Foo::T*, self::Foo::T*>*
+    return #C8;
+  get v9() → core::Map<self::Foo::T*, (self::Foo::T*) →* self::Foo::T*>*
+    return #C9;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar<T extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::Bar<self::Bar::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Bar<Null> {}
+  #C2 = self::Bar<core::List<Null>*> {}
+  #C3 = self::Bar<(core::Object*) →* Null> {}
+  #C4 = self::Bar<((Null) →* core::Object*) →* Null> {}
+  #C5 = <Null>[]
+  #C6 = <(core::Object*) →* Null>[]
+  #C7 = <Null, Null>{)
+  #C8 = <(core::Object*) →* Null, Null>{)
+  #C9 = <Null, (core::Object*) →* Null>{)
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///const_invocation.dart:
+- Bar. (from org-dartlang-testcase:///const_invocation.dart:24:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/inference_new/dependency_only_if_generic_method.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/dependency_only_if_generic_method.dart.weak.modular.expect
new file mode 100644
index 0000000..a062019
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/dependency_only_if_generic_method.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/dependency_only_if_generic_method.dart:18:5: Error: Can't infer the type of 'b': circularity found during type inference.
+// Specify the type explicitly.
+// var b = /*@ returnType=() ->* invalid-type */ () =>
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method f<T extends core::Object* = dynamic>(self::A::f::T* t) → self::A::f::T*
+    return t;
+  method g(dynamic i) → core::int*
+    return 0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::A* a = new self::A::•();
+static field invalid-type b = () → () →* invalid-type => self::a.{self::A::f}<() →* invalid-type>(self::c){(() →* invalid-type) →* () →* invalid-type};
+static field () →* invalid-type c = () → invalid-type => self::a.{self::A::f}<invalid-type>(self::b){(invalid-type) →* invalid-type};
+static field () →* () →* core::int* d = () → () →* core::int* => self::a.{self::A::f}<() →* core::int*>(self::e){(() →* core::int*) →* () →* core::int*};
+static field () →* core::int* e = () → core::int* => self::a.{self::A::g}(self::d){(dynamic) →* core::int*};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/dependency_only_if_overloaded.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/dependency_only_if_overloaded.dart.weak.modular.expect
new file mode 100644
index 0000000..3ae5f85
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/dependency_only_if_overloaded.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/dependency_only_if_overloaded.dart:15:5: Error: Can't infer the type of 'a': circularity found during type inference.
+// Specify the type explicitly.
+// var a = /*@ returnType=num* */ () => intValue /*@target=num.+*/ + b;
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field core::int* intValue = 0;
+static field core::num* numValue = 0;
+static field core::double* doubleValue = 0.0;
+static field invalid-type a = () → core::num* => self::intValue.{core::num::+}(self::b as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*};
+static field dynamic b = self::a{dynamic}.call();
+static field () →* core::num* c = () → core::num* => self::numValue.{core::num::+}(self::d){(core::num*) →* core::num*};
+static field core::num* d = self::c(){() →* core::num*};
+static field () →* core::double* e = () → core::double* => self::doubleValue.{core::double::+}(self::f){(core::num*) →* core::double*};
+static field core::double* f = self::e(){() →* core::double*};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/do_loop.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/do_loop.dart.weak.modular.expect
new file mode 100644
index 0000000..2639877
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/do_loop.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method test() → void {
+  do {
+    core::int* x = 0;
+  }
+  while (self::f<core::bool*>())
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/downwards_inference_inside_top_level.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/downwards_inference_inside_top_level.dart.weak.modular.expect
new file mode 100644
index 0000000..f211b44
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/downwards_inference_inside_top_level.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field self::B<core::int*>* b = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(self::B::T* x) → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::List<self::B<core::int*>*>* t3 = <self::B<core::int*>*>[new self::B::•<core::int*>(3)];
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/downwards_inference_inside_top_level_2.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/downwards_inference_inside_top_level_2.dart.weak.modular.expect
new file mode 100644
index 0000000..aaa7123
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/downwards_inference_inside_top_level_2.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  constructor •(self::A::T* x) → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::List<self::A<core::int*>*>* t2 = <self::A<core::int*>*>[new self::A::•<core::int*>(2)];
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/field_inference_circularity.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/field_inference_circularity.dart.weak.modular.expect
new file mode 100644
index 0000000..b83a5f8
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/field_inference_circularity.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/field_inference_circularity.dart:12:7: Error: Can't infer the type of 'x': circularity found during type inference.
+// Specify the type explicitly.
+//   var x = /*@returnType=invalid-type*/ () => new B(). /*@target=B.x*/ x;
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field invalid-type x = () → invalid-type => new self::B::•().{self::B::x}{invalid-type};
+  field () →* invalid-type y = () → invalid-type => new self::B::•().{self::B::x}{invalid-type};
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  field invalid-type x = null;
+  field () →* invalid-type y = null;
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/for_each_identifier_downwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/for_each_identifier_downwards.dart.weak.modular.expect
new file mode 100644
index 0000000..0a972fb
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/for_each_identifier_downwards.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  field self::A* aField = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  set aSetter(self::A* value) → void {}
+  method test() → void {
+    self::A* aLocal;
+    for (final self::A* #t1 in self::f<core::Iterable<self::A*>*>()) {
+      aLocal = #t1;
+    }
+    for (final self::A* #t2 in self::f<core::Iterable<self::A*>*>()) {
+      this.{self::C::aField} = #t2;
+    }
+    for (final self::A* #t3 in self::f<core::Iterable<self::A*>*>()) {
+      this.{self::C::aSetter} = #t3;
+    }
+    for (final self::A* #t4 in self::f<core::Iterable<self::A*>*>()) {
+      self::aTopLevel = #t4;
+    }
+    for (final self::A* #t5 in self::f<core::Iterable<self::A*>*>()) {
+      self::aTopLevelSetter = #t5;
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::A* aTopLevel;
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static set aTopLevelSetter(self::A* value) → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/for_each_invalid_iterable.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/for_each_invalid_iterable.dart.weak.modular.expect
new file mode 100644
index 0000000..727e04a
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/for_each_invalid_iterable.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/for_each_invalid_iterable.dart:10:17: Error: The type 'String' used in the 'for' loop must implement 'Iterable<dynamic>'.
+//  - 'Iterable' is from 'dart:core'.
+//   for (int x in s) {}
+//                 ^
+//
+// pkg/front_end/testcases/inference_new/for_each_invalid_iterable.dart:11:23: Error: The type 'String' used in the 'for' loop must implement 'Stream<dynamic>'.
+//  - 'Stream' is from 'dart:async'.
+//   await for (int x in s) {}
+//                       ^
+//
+// pkg/front_end/testcases/inference_new/for_each_invalid_iterable.dart:13:13: Error: The type 'String' used in the 'for' loop must implement 'Iterable<dynamic>'.
+//  - 'Iterable' is from 'dart:core'.
+//   for (y in s) {}
+//             ^
+//
+// pkg/front_end/testcases/inference_new/for_each_invalid_iterable.dart:14:19: Error: The type 'String' used in the 'for' loop must implement 'Stream<dynamic>'.
+//  - 'Stream' is from 'dart:async'.
+//   await for (y in s) {}
+//                   ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+static method test() → dynamic async {
+  core::String* s;
+  for (final dynamic #t1 in invalid-expression "pkg/front_end/testcases/inference_new/for_each_invalid_iterable.dart:10:17: Error: The type 'String' used in the 'for' loop must implement 'Iterable<dynamic>'.
+ - 'Iterable' is from 'dart:core'.
+  for (int x in s) {}
+                ^" in s as{TypeError} core::Iterable<dynamic>*) {
+    core::int* x = #t1 as{TypeError,ForDynamic} core::int*;
+  }
+  await for (final dynamic #t2 in invalid-expression "pkg/front_end/testcases/inference_new/for_each_invalid_iterable.dart:11:23: Error: The type 'String' used in the 'for' loop must implement 'Stream<dynamic>'.
+ - 'Stream' is from 'dart:async'.
+  await for (int x in s) {}
+                      ^" in s as{TypeError} asy::Stream<dynamic>*) {
+    core::int* x = #t2 as{TypeError,ForDynamic} core::int*;
+  }
+  core::int* y;
+  for (final dynamic #t3 in invalid-expression "pkg/front_end/testcases/inference_new/for_each_invalid_iterable.dart:13:13: Error: The type 'String' used in the 'for' loop must implement 'Iterable<dynamic>'.
+ - 'Iterable' is from 'dart:core'.
+  for (y in s) {}
+            ^" in s as{TypeError} core::Iterable<dynamic>*) {
+    y = #t3 as{TypeError,ForDynamic} core::int*;
+  }
+  await for (final dynamic #t4 in invalid-expression "pkg/front_end/testcases/inference_new/for_each_invalid_iterable.dart:14:19: Error: The type 'String' used in the 'for' loop must implement 'Stream<dynamic>'.
+ - 'Stream' is from 'dart:async'.
+  await for (y in s) {}
+                  ^" in s as{TypeError} asy::Stream<dynamic>*) {
+    y = #t4 as{TypeError,ForDynamic} core::int*;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/for_each_outer_var_type.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/for_each_outer_var_type.dart.weak.modular.expect
new file mode 100644
index 0000000..e195507
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/for_each_outer_var_type.dart.weak.modular.expect
@@ -0,0 +1,84 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/for_each_outer_var_type.dart:26:10: Error: A value of type 'A' can't be assigned to a variable of type 'int'.
+//  - 'A' is from 'pkg/front_end/testcases/inference_new/for_each_outer_var_type.dart'.
+// Try changing the type of the variable.
+//   for (i in iterable) {}
+//          ^
+//
+// pkg/front_end/testcases/inference_new/for_each_outer_var_type.dart:27:16: Error: A value of type 'A' can't be assigned to a variable of type 'int'.
+//  - 'A' is from 'pkg/front_end/testcases/inference_new/for_each_outer_var_type.dart'.
+// Try changing the type of the variable.
+//   await for (i in stream) {}
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method test() → dynamic async {
+  core::Iterable<self::A*>* iterable;
+  asy::Stream<self::A*>* stream;
+  self::A* a;
+  self::B* b;
+  core::int* i;
+  for (final self::A* #t1 in iterable) {
+    a = #t1;
+  }
+  await for (final self::A* #t2 in stream) {
+    a = #t2;
+  }
+  for (final self::A* #t3 in iterable) {
+    b = #t3 as{TypeError} self::B*;
+  }
+  await for (final self::A* #t4 in stream) {
+    b = #t4 as{TypeError} self::B*;
+  }
+  for (final self::A* #t5 in iterable) {
+    i = invalid-expression "pkg/front_end/testcases/inference_new/for_each_outer_var_type.dart:26:10: Error: A value of type 'A' can't be assigned to a variable of type 'int'.
+ - 'A' is from 'pkg/front_end/testcases/inference_new/for_each_outer_var_type.dart'.
+Try changing the type of the variable.
+  for (i in iterable) {}
+         ^" in #t5 as{TypeError} core::int*;
+  }
+  await for (final self::A* #t6 in stream) {
+    i = invalid-expression "pkg/front_end/testcases/inference_new/for_each_outer_var_type.dart:27:16: Error: A value of type 'A' can't be assigned to a variable of type 'int'.
+ - 'A' is from 'pkg/front_end/testcases/inference_new/for_each_outer_var_type.dart'.
+Try changing the type of the variable.
+  await for (i in stream) {}
+               ^" in #t6 as{TypeError} core::int*;
+  }
+  for (final self::A* #t7 in self::f<core::Iterable<self::A*>*>()) {
+    a = #t7;
+  }
+  await for (final self::A* #t8 in self::f<asy::Stream<self::A*>*>()) {
+    a = #t8;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/indexed_assign_combiner.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/indexed_assign_combiner.dart.weak.modular.expect
new file mode 100644
index 0000000..cf8fb9e
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/indexed_assign_combiner.dart.weak.modular.expect
@@ -0,0 +1,125 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator +(core::int* value) → self::C*
+    return null;
+  operator *(self::D* value) → self::C*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  operator +(core::int* value) → self::E*
+    return null;
+  operator *(self::F* value) → self::E*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E extends core::Object {
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F extends core::Object {
+  synthetic constructor •() → self::F*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class G extends core::Object {
+  synthetic constructor •() → self::G*
+    : super core::Object::•()
+    ;
+  operator [](core::int* i) → self::A*
+    return null;
+  operator []=(core::int* i, self::B* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method test1(self::G* g) → void {
+  let final self::G* #t1 = g in let final core::int* #t2 = 0 in #t1.{self::G::[]=}(#t2, #t1.{self::G::[]}(#t2){(core::int*) →* self::A*}.{self::A::*}(self::f<self::D*>()){(self::D*) →* self::C*}){(core::int*, self::B*) →* void};
+  self::C* x = let final self::G* #t3 = g in let final core::int* #t4 = 0 in let final self::C* #t5 = #t3.{self::G::[]}(#t4){(core::int*) →* self::A*}.{self::A::*}(self::f<self::D*>()){(self::D*) →* self::C*} in let final void #t6 = #t3.{self::G::[]=}(#t4, #t5){(core::int*, self::B*) →* void} in #t5;
+}
+static method test2(self::G* g) → void {
+  let final self::G* #t7 = g in let final core::int* #t8 = 0 in let final self::C* #t9 = #t7.{self::G::[]}(#t8){(core::int*) →* self::A*}.{self::A::+}(1){(core::int*) →* self::C*} in let final void #t10 = #t7.{self::G::[]=}(#t8, #t9){(core::int*, self::B*) →* void} in #t9;
+  self::C* x = let final self::G* #t11 = g in let final core::int* #t12 = 0 in let final self::C* #t13 = #t11.{self::G::[]}(#t12){(core::int*) →* self::A*}.{self::A::+}(1){(core::int*) →* self::C*} in let final void #t14 = #t11.{self::G::[]=}(#t12, #t13){(core::int*, self::B*) →* void} in #t13;
+}
+static method test3(self::G* g) → void {
+  let final self::G* #t15 = g in let final core::int* #t16 = 0 in #t15.{self::G::[]=}(#t16, #t15.{self::G::[]}(#t16){(core::int*) →* self::A*}.{self::A::+}(1){(core::int*) →* self::C*}){(core::int*, self::B*) →* void};
+  self::A* x = let final self::G* #t17 = g in let final core::int* #t18 = 0 in let final self::A* #t19 = #t17.{self::G::[]}(#t18){(core::int*) →* self::A*} in let final void #t20 = #t17.{self::G::[]=}(#t18, #t19.{self::A::+}(1){(core::int*) →* self::C*}){(core::int*, self::B*) →* void} in #t19;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_implicit_this.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_implicit_this.dart.weak.modular.expect
new file mode 100644
index 0000000..43a39ef
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_implicit_this.dart.weak.modular.expect
@@ -0,0 +1,72 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class Test extends core::Object {
+  field self::B* member = null;
+  synthetic constructor •() → self::Test*
+    : super core::Object::•()
+    ;
+  method test() → void {
+    this.{self::Test::member} = self::f<self::B*>();
+    this.{self::Test::member}{self::B*} == null ?{self::B*} this.{self::Test::member} = self::f<self::B*>() : null;
+    this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+    this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+    this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+    this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*};
+    this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*};
+    self::B* v1 = this.{self::Test::member} = self::f<self::B*>();
+    self::B* v2 = let final self::B* #t1 = this.{self::Test::member}{self::B*} in #t1 == null ?{self::B*} this.{self::Test::member} = self::f<self::B*>() : #t1;
+    self::A* v3 = this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+    self::B* v4 = this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+    self::C* v5 = this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+    self::B* v6 = this.{self::Test::member} = this.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*};
+    self::B* v7 = let final self::B* #t2 = this.{self::Test::member}{self::B*} in let final self::B* #t3 = this.{self::Test::member} = #t2.{self::B::-}(1){(core::int*) →* self::B*} in #t2;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_implicit_this_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_implicit_this_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..c9e63c0
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_implicit_this_upwards.dart.weak.modular.expect
@@ -0,0 +1,93 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Test1 extends core::Object {
+  field core::int* t = null;
+  synthetic constructor •() → self::Test1*
+    : super core::Object::•()
+    ;
+  method test() → void {
+    core::int* v1 = this.{self::Test1::t} = self::getInt();
+    core::num* v2 = this.{self::Test1::t} = self::getNum() as{TypeError} core::int*;
+    core::int* v4 = let final core::int* #t1 = this.{self::Test1::t}{core::int*} in #t1 == null ?{core::int*} this.{self::Test1::t} = self::getInt() : #t1;
+    core::num* v5 = let final core::int* #t2 = this.{self::Test1::t}{core::int*} in #t2 == null ?{core::num*} this.{self::Test1::t} = self::getNum() as{TypeError} core::int* : #t2;
+    core::int* v7 = this.{self::Test1::t} = this.{self::Test1::t}{core::int*}.{core::num::+}(self::getInt()){(core::num*) →* core::int*};
+    core::num* v8 = this.{self::Test1::t} = this.{self::Test1::t}{core::int*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::int*;
+    core::int* v10 = this.{self::Test1::t} = this.{self::Test1::t}{core::int*}.{core::num::+}(1){(core::num*) →* core::int*};
+    core::int* v11 = let final core::int* #t3 = this.{self::Test1::t}{core::int*} in let final core::int* #t4 = this.{self::Test1::t} = #t3.{core::num::+}(1){(core::num*) →* core::int*} in #t3;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test2 extends core::Object {
+  field core::num* t = null;
+  synthetic constructor •() → self::Test2*
+    : super core::Object::•()
+    ;
+  method test() → void {
+    core::int* v1 = this.{self::Test2::t} = self::getInt();
+    core::num* v2 = this.{self::Test2::t} = self::getNum();
+    core::double* v3 = this.{self::Test2::t} = self::getDouble();
+    core::num* v4 = let final core::num* #t5 = this.{self::Test2::t}{core::num*} in #t5 == null ?{core::num*} this.{self::Test2::t} = self::getInt() : #t5;
+    core::num* v5 = let final core::num* #t6 = this.{self::Test2::t}{core::num*} in #t6 == null ?{core::num*} this.{self::Test2::t} = self::getNum() : #t6;
+    core::num* v6 = let final core::num* #t7 = this.{self::Test2::t}{core::num*} in #t7 == null ?{core::num*} this.{self::Test2::t} = self::getDouble() : #t7;
+    core::num* v7 = this.{self::Test2::t} = this.{self::Test2::t}{core::num*}.{core::num::+}(self::getInt()){(core::num*) →* core::num*};
+    core::num* v8 = this.{self::Test2::t} = this.{self::Test2::t}{core::num*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*};
+    core::num* v9 = this.{self::Test2::t} = this.{self::Test2::t}{core::num*}.{core::num::+}(self::getDouble()){(core::num*) →* core::num*};
+    core::num* v10 = this.{self::Test2::t} = this.{self::Test2::t}{core::num*}.{core::num::+}(1){(core::num*) →* core::num*};
+    core::num* v11 = let final core::num* #t8 = this.{self::Test2::t}{core::num*} in let final core::num* #t9 = this.{self::Test2::t} = #t8.{core::num::+}(1){(core::num*) →* core::num*} in #t8;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test3 extends core::Object {
+  field core::double* t = null;
+  synthetic constructor •() → self::Test3*
+    : super core::Object::•()
+    ;
+  method test3() → void {
+    core::num* v2 = this.{self::Test3::t} = self::getNum() as{TypeError} core::double*;
+    core::double* v3 = this.{self::Test3::t} = self::getDouble();
+    core::num* v5 = let final core::double* #t10 = this.{self::Test3::t}{core::double*} in #t10 == null ?{core::num*} this.{self::Test3::t} = self::getNum() as{TypeError} core::double* : #t10;
+    core::double* v6 = let final core::double* #t11 = this.{self::Test3::t}{core::double*} in #t11 == null ?{core::double*} this.{self::Test3::t} = self::getDouble() : #t11;
+    core::double* v7 = this.{self::Test3::t} = this.{self::Test3::t}{core::double*}.{core::double::+}(self::getInt()){(core::num*) →* core::double*};
+    core::double* v8 = this.{self::Test3::t} = this.{self::Test3::t}{core::double*}.{core::double::+}(self::getNum()){(core::num*) →* core::double*};
+    core::double* v9 = this.{self::Test3::t} = this.{self::Test3::t}{core::double*}.{core::double::+}(self::getDouble()){(core::num*) →* core::double*};
+    core::double* v10 = this.{self::Test3::t} = this.{self::Test3::t}{core::double*}.{core::double::+}(1){(core::num*) →* core::double*};
+    core::double* v11 = let final core::double* #t12 = this.{self::Test3::t}{core::double*} in let final core::double* #t13 = this.{self::Test3::t} = #t12.{core::double::+}(1){(core::num*) →* core::double*} in #t12;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method getInt() → core::int*
+  return 0;
+static method getNum() → core::num*
+  return 0;
+static method getDouble() → core::double*
+  return 0.0;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_index.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_index.dart.weak.modular.expect
new file mode 100644
index 0000000..f6ef830
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_index.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<core::double*>* a = <core::double*>[];
+static field core::double* b = let final core::List<core::double*>* #t1 = self::a in let final core::int* #t2 = 0 in let final core::double* #t3 = 1.0 in let final void #t4 = #t1.{core::List::[]=}(#t2, #t3){(core::int*, core::double*) →* void} in #t3;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_index_full.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_index_full.dart.weak.modular.expect
new file mode 100644
index 0000000..8b4ab90
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_index_full.dart.weak.modular.expect
@@ -0,0 +1,92 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Index extends core::Object {
+  synthetic constructor •() → self::Index*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class Test extends core::Object {
+  synthetic constructor •() → self::Test*
+    : super core::Object::•()
+    ;
+  operator [](self::Index* i) → self::B*
+    return null;
+  operator []=(self::Index* i, self::B* v) → void {}
+  method test() → void {
+    self::Test* t = self::f<self::Test*>();
+    t.{self::Test::[]=}(self::f<self::Index*>(), self::f<self::B*>()){(self::Index*, self::B*) →* void};
+    let final self::Test* #t1 = t in let final self::Index* #t2 = self::f<self::Index*>() in #t1.{self::Test::[]}(#t2){(self::Index*) →* self::B*} == null ?{self::B*} #t1.{self::Test::[]=}(#t2, self::f<self::B*>()){(self::Index*, self::B*) →* void} : null;
+    let final self::Test* #t3 = t in let final self::Index* #t4 = self::f<self::Index*>() in #t3.{self::Test::[]=}(#t4, #t3.{self::Test::[]}(#t4){(self::Index*) →* self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*){(self::Index*, self::B*) →* void};
+    let final self::Test* #t5 = t in let final self::Index* #t6 = self::f<self::Index*>() in #t5.{self::Test::[]=}(#t6, #t5.{self::Test::[]}(#t6){(self::Index*) →* self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*}){(self::Index*, self::B*) →* void};
+    let final self::Test* #t7 = t in let final self::Index* #t8 = self::f<self::Index*>() in #t7.{self::Test::[]=}(#t8, #t7.{self::Test::[]}(#t8){(self::Index*) →* self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*}){(self::Index*, self::B*) →* void};
+    t.{self::Test::[]}(self::f<self::Index*>()){(self::Index*) →* self::B*};
+    let final self::Test* #t9 = t in let final self::Index* #t10 = self::f<self::Index*>() in let final self::B* #t11 = #t9.{self::Test::[]}(#t10){(self::Index*) →* self::B*}.{self::B::-}(1){(core::int*) →* self::B*} in let final void #t12 = #t9.{self::Test::[]=}(#t10, #t11){(self::Index*, self::B*) →* void} in #t11;
+    let final self::Test* #t13 = t in let final self::Index* #t14 = self::f<self::Index*>() in #t13.{self::Test::[]=}(#t14, #t13.{self::Test::[]}(#t14){(self::Index*) →* self::B*}.{self::B::-}(1){(core::int*) →* self::B*}){(self::Index*, self::B*) →* void};
+    self::B* v1 = let final self::Test* #t15 = t in let final self::Index* #t16 = self::f<self::Index*>() in let final self::B* #t17 = self::f<self::B*>() in let final void #t18 = #t15.{self::Test::[]=}(#t16, #t17){(self::Index*, self::B*) →* void} in #t17;
+    self::B* v2 = let final self::Test* #t19 = t in let final self::Index* #t20 = self::f<self::Index*>() in let final self::B* #t21 = #t19.{self::Test::[]}(#t20){(self::Index*) →* self::B*} in #t21 == null ?{self::B*} let final self::B* #t22 = self::f<self::B*>() in let final void #t23 = #t19.{self::Test::[]=}(#t20, #t22){(self::Index*, self::B*) →* void} in #t22 : #t21;
+    self::A* v3 = let final self::Test* #t24 = t in let final self::Index* #t25 = self::f<self::Index*>() in let final self::A* #t26 = #t24.{self::Test::[]}(#t25){(self::Index*) →* self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B* in let final void #t27 = #t24.{self::Test::[]=}(#t25, #t26){(self::Index*, self::B*) →* void} in #t26;
+    self::B* v4 = let final self::Test* #t28 = t in let final self::Index* #t29 = self::f<self::Index*>() in let final self::B* #t30 = #t28.{self::Test::[]}(#t29){(self::Index*) →* self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*} in let final void #t31 = #t28.{self::Test::[]=}(#t29, #t30){(self::Index*, self::B*) →* void} in #t30;
+    self::C* v5 = let final self::Test* #t32 = t in let final self::Index* #t33 = self::f<self::Index*>() in let final self::C* #t34 = #t32.{self::Test::[]}(#t33){(self::Index*) →* self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*} in let final void #t35 = #t32.{self::Test::[]=}(#t33, #t34){(self::Index*, self::B*) →* void} in #t34;
+    self::B* v6 = t.{self::Test::[]}(self::f<self::Index*>()){(self::Index*) →* self::B*};
+    self::B* v7 = let final self::Test* #t36 = t in let final self::Index* #t37 = self::f<self::Index*>() in let final self::B* #t38 = #t36.{self::Test::[]}(#t37){(self::Index*) →* self::B*}.{self::B::-}(1){(core::int*) →* self::B*} in let final void #t39 = #t36.{self::Test::[]=}(#t37, #t38){(self::Index*, self::B*) →* void} in #t38;
+    self::B* v8 = let final self::Test* #t40 = t in let final self::Index* #t41 = self::f<self::Index*>() in let final self::B* #t42 = #t40.{self::Test::[]}(#t41){(self::Index*) →* self::B*} in let final void #t43 = #t40.{self::Test::[]=}(#t41, #t42.{self::B::-}(1){(core::int*) →* self::B*}){(self::Index*, self::B*) →* void} in #t42;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_index_set_vs_get.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_index_set_vs_get.dart.weak.modular.expect
new file mode 100644
index 0000000..685af9c
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_index_set_vs_get.dart.weak.modular.expect
@@ -0,0 +1,101 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Index extends core::Object {
+  synthetic constructor •() → self::Index*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator +(self::F* v) → self::C*
+    return null;
+  operator -(core::int* i) → self::C*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::E* v) → self::D*
+    return null;
+  operator -(core::int* i) → self::D*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+}
+class E extends self::D {
+  synthetic constructor •() → self::E*
+    : super self::D::•()
+    ;
+}
+class F extends self::E {
+  synthetic constructor •() → self::F*
+    : super self::E::•()
+    ;
+}
+class Test extends core::Object {
+  synthetic constructor •() → self::Test*
+    : super core::Object::•()
+    ;
+  operator [](self::Index* i) → self::B*
+    return null;
+  operator []=(self::Index* i, self::A* v) → void {}
+  method test() → void {
+    self::Test* t = self::f<self::Test*>();
+    t.{self::Test::[]=}(self::f<self::Index*>(), self::f<self::A*>()){(self::Index*, self::A*) →* void};
+    let final self::Test* #t1 = t in let final self::Index* #t2 = self::f<self::Index*>() in #t1.{self::Test::[]}(#t2){(self::Index*) →* self::B*} == null ?{self::A*} #t1.{self::Test::[]=}(#t2, self::f<self::A*>()){(self::Index*, self::A*) →* void} : null;
+    let final self::Test* #t3 = t in let final self::Index* #t4 = self::f<self::Index*>() in #t3.{self::Test::[]=}(#t4, #t3.{self::Test::[]}(#t4){(self::Index*) →* self::B*}.{self::B::+}(self::f<self::E*>()){(self::E*) →* self::D*}){(self::Index*, self::A*) →* void};
+    let final self::Test* #t5 = t in let final self::Index* #t6 = self::f<self::Index*>() in let final self::D* #t7 = #t5.{self::Test::[]}(#t6){(self::Index*) →* self::B*}.{self::B::-}(1){(core::int*) →* self::D*} in let final void #t8 = #t5.{self::Test::[]=}(#t6, #t7){(self::Index*, self::A*) →* void} in #t7;
+    let final self::Test* #t9 = t in let final self::Index* #t10 = self::f<self::Index*>() in #t9.{self::Test::[]=}(#t10, #t9.{self::Test::[]}(#t10){(self::Index*) →* self::B*}.{self::B::-}(1){(core::int*) →* self::D*}){(self::Index*, self::A*) →* void};
+    self::A* v1 = let final self::Test* #t11 = t in let final self::Index* #t12 = self::f<self::Index*>() in let final self::A* #t13 = self::f<self::A*>() in let final void #t14 = #t11.{self::Test::[]=}(#t12, #t13){(self::Index*, self::A*) →* void} in #t13;
+    self::A* v2 = let final self::Test* #t15 = t in let final self::Index* #t16 = self::f<self::Index*>() in let final self::B* #t17 = #t15.{self::Test::[]}(#t16){(self::Index*) →* self::B*} in #t17 == null ?{self::A*} let final self::A* #t18 = self::f<self::A*>() in let final void #t19 = #t15.{self::Test::[]=}(#t16, #t18){(self::Index*, self::A*) →* void} in #t18 : #t17;
+    self::D* v3 = let final self::Test* #t20 = t in let final self::Index* #t21 = self::f<self::Index*>() in let final self::D* #t22 = #t20.{self::Test::[]}(#t21){(self::Index*) →* self::B*}.{self::B::+}(self::f<self::E*>()){(self::E*) →* self::D*} in let final void #t23 = #t20.{self::Test::[]=}(#t21, #t22){(self::Index*, self::A*) →* void} in #t22;
+    self::D* v4 = let final self::Test* #t24 = t in let final self::Index* #t25 = self::f<self::Index*>() in let final self::D* #t26 = #t24.{self::Test::[]}(#t25){(self::Index*) →* self::B*}.{self::B::-}(1){(core::int*) →* self::D*} in let final void #t27 = #t24.{self::Test::[]=}(#t25, #t26){(self::Index*, self::A*) →* void} in #t26;
+    self::B* v5 = let final self::Test* #t28 = t in let final self::Index* #t29 = self::f<self::Index*>() in let final self::B* #t30 = #t28.{self::Test::[]}(#t29){(self::Index*) →* self::B*} in let final void #t31 = #t28.{self::Test::[]=}(#t29, #t30.{self::B::-}(1){(core::int*) →* self::D*}){(self::Index*, self::A*) →* void} in #t30;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_index_super.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_index_super.dart.weak.modular.expect
new file mode 100644
index 0000000..3a7a814
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_index_super.dart.weak.modular.expect
@@ -0,0 +1,94 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Index extends core::Object {
+  synthetic constructor •() → self::Index*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class Base extends core::Object {
+  synthetic constructor •() → self::Base*
+    : super core::Object::•()
+    ;
+  operator [](self::Index* i) → self::B*
+    return null;
+  operator []=(self::Index* i, self::B* v) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test extends self::Base {
+  synthetic constructor •() → self::Test*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    super.{self::Base::[]=}(self::f<self::Index*>(), self::f<self::B*>());
+    let final self::Index* #t1 = self::f<self::Index*>() in super.{self::Base::[]}(#t1) == null ?{self::B*} super.{self::Base::[]=}(#t1, self::f<self::B*>()) : null;
+    let final self::Index* #t2 = self::f<self::Index*>() in super.{self::Base::[]=}(#t2, super.{self::Base::[]}(#t2).{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*);
+    let final self::Index* #t3 = self::f<self::Index*>() in super.{self::Base::[]=}(#t3, super.{self::Base::[]}(#t3).{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*});
+    let final self::Index* #t4 = self::f<self::Index*>() in super.{self::Base::[]=}(#t4, super.{self::Base::[]}(#t4).{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*});
+    let final self::Index* #t5 = self::f<self::Index*>() in let final self::B* #t6 = super.{self::Base::[]}(#t5).{self::B::-}(1){(core::int*) →* self::B*} in let final void #t7 = super.{self::Base::[]=}(#t5, #t6) in #t6;
+    let final self::Index* #t8 = self::f<self::Index*>() in super.{self::Base::[]=}(#t8, super.{self::Base::[]}(#t8).{self::B::-}(1){(core::int*) →* self::B*});
+    self::B* v1 = let final self::Index* #t9 = self::f<self::Index*>() in let final self::B* #t10 = self::f<self::B*>() in let final void #t11 = super.{self::Base::[]=}(#t9, #t10) in #t10;
+    self::B* v2 = let final self::Index* #t12 = self::f<self::Index*>() in let final self::B* #t13 = super.{self::Base::[]}(#t12) in #t13 == null ?{self::B*} let final self::B* #t14 = self::f<self::B*>() in let final void #t15 = super.{self::Base::[]=}(#t12, #t14) in #t14 : #t13;
+    self::A* v3 = let final self::Index* #t16 = self::f<self::Index*>() in let final self::A* #t17 = super.{self::Base::[]}(#t16).{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B* in let final void #t18 = super.{self::Base::[]=}(#t16, #t17) in #t17;
+    self::B* v4 = let final self::Index* #t19 = self::f<self::Index*>() in let final self::B* #t20 = super.{self::Base::[]}(#t19).{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*} in let final void #t21 = super.{self::Base::[]=}(#t19, #t20) in #t20;
+    self::C* v5 = let final self::Index* #t22 = self::f<self::Index*>() in let final self::C* #t23 = super.{self::Base::[]}(#t22).{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*} in let final void #t24 = super.{self::Base::[]=}(#t22, #t23) in #t23;
+    self::B* v6 = let final self::Index* #t25 = self::f<self::Index*>() in let final self::B* #t26 = super.{self::Base::[]}(#t25).{self::B::-}(1){(core::int*) →* self::B*} in let final void #t27 = super.{self::Base::[]=}(#t25, #t26) in #t26;
+    self::B* v7 = let final self::Index* #t28 = self::f<self::Index*>() in let final self::B* #t29 = super.{self::Base::[]}(#t28) in let final void #t30 = super.{self::Base::[]=}(#t28, #t29.{self::B::-}(1){(core::int*) →* self::B*}) in #t29;
+  }
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..92e9469
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart.weak.modular.expect
@@ -0,0 +1,224 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart:106:31: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+//             /*@target=num.+*/ += getInt();
+//                               ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart:116:50: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+//     var /*@ type=int* */ v10 = /*@target=num.+*/ ++super
+//                                                  ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart:120:33: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+//         ['x'] /*@target=num.+*/ ++;
+//                                 ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart:244:34: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//             /*@target=double.+*/ += getInt();
+//                                  ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart:248:34: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//             /*@target=double.+*/ += getNum();
+//                                  ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart:250:56: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//     var /*@ type=double* */ v10 = /*@target=double.+*/ ++super
+//                                                        ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart:254:36: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//         ['x'] /*@target=double.+*/ ++;
+//                                    ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Base<T extends core::Object* = dynamic, U extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Base<self::Base::T*, self::Base::U*>*
+    : super core::Object::•()
+    ;
+  operator [](core::String* s) → self::Base::T*
+    return this.{self::Base::getValue}(s){(core::String*) →* self::Base::T*};
+  operator []=(core::String* s, covariant-by-class self::Base::U* v) → void
+    return this.{self::Base::setValue}(s, v){(core::String*, self::Base::U*) →* void};
+  abstract method getValue(core::String* s) → self::Base::T*;
+  abstract method setValue(core::String* s, covariant-by-class self::Base::U* v) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Test1 extends self::Base<core::int*, core::int*> {
+  synthetic constructor •() → self::Test1*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    core::int* v1 = let final core::String* #t1 = "x" in let final core::int* #t2 = self::getInt() in let final void #t3 = super.{self::Base::[]=}(#t1, #t2) in #t2;
+    core::num* v2 = let final core::String* #t4 = "x" in let final core::num* #t5 = self::getNum() as{TypeError} core::int* in let final void #t6 = super.{self::Base::[]=}(#t4, #t5) in #t5;
+    core::int* v4 = let final core::String* #t7 = "x" in let final core::int* #t8 = super.{self::Base::[]}(#t7) in #t8 == null ?{core::int*} let final core::int* #t9 = self::getInt() in let final void #t10 = super.{self::Base::[]=}(#t7, #t9) in #t9 : #t8;
+    core::num* v5 = let final core::String* #t11 = "x" in let final core::int* #t12 = super.{self::Base::[]}(#t11) in #t12 == null ?{core::num*} let final core::num* #t13 = self::getNum() as{TypeError} core::int* in let final void #t14 = super.{self::Base::[]=}(#t11, #t13) in #t13 : #t12;
+    core::int* v7 = let final core::String* #t15 = "x" in let final core::int* #t16 = super.{self::Base::[]}(#t15).{core::num::+}(self::getInt()){(core::num*) →* core::int*} in let final void #t17 = super.{self::Base::[]=}(#t15, #t16) in #t16;
+    core::num* v8 = let final core::String* #t18 = "x" in let final core::num* #t19 = super.{self::Base::[]}(#t18).{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::int* in let final void #t20 = super.{self::Base::[]=}(#t18, #t19) in #t19;
+    core::int* v10 = let final core::String* #t21 = "x" in let final core::int* #t22 = super.{self::Base::[]}(#t21).{core::num::+}(1){(core::num*) →* core::int*} in let final void #t23 = super.{self::Base::[]=}(#t21, #t22) in #t22;
+    core::int* v11 = let final core::String* #t24 = "x" in let final core::int* #t25 = super.{self::Base::[]}(#t24) in let final void #t26 = super.{self::Base::[]=}(#t24, #t25.{core::num::+}(1){(core::num*) →* core::int*}) in #t25;
+  }
+}
+abstract class Test2 extends self::Base<core::int*, core::num*> {
+  synthetic constructor •() → self::Test2*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    core::int* v1 = let final core::String* #t27 = "x" in let final core::int* #t28 = self::getInt() in let final void #t29 = super.{self::Base::[]=}(#t27, #t28) in #t28;
+    core::num* v2 = let final core::String* #t30 = "x" in let final core::num* #t31 = self::getNum() in let final void #t32 = super.{self::Base::[]=}(#t30, #t31) in #t31;
+    core::double* v3 = let final core::String* #t33 = "x" in let final core::double* #t34 = self::getDouble() in let final void #t35 = super.{self::Base::[]=}(#t33, #t34) in #t34;
+    core::int* v4 = let final core::String* #t36 = "x" in let final core::int* #t37 = super.{self::Base::[]}(#t36) in #t37 == null ?{core::int*} let final core::int* #t38 = self::getInt() in let final void #t39 = super.{self::Base::[]=}(#t36, #t38) in #t38 : #t37;
+    core::num* v5 = let final core::String* #t40 = "x" in let final core::int* #t41 = super.{self::Base::[]}(#t40) in #t41 == null ?{core::num*} let final core::num* #t42 = self::getNum() in let final void #t43 = super.{self::Base::[]=}(#t40, #t42) in #t42 : #t41;
+    core::num* v6 = let final core::String* #t44 = "x" in let final core::int* #t45 = super.{self::Base::[]}(#t44) in #t45 == null ?{core::num*} let final core::double* #t46 = self::getDouble() in let final void #t47 = super.{self::Base::[]=}(#t44, #t46) in #t46 : #t45;
+    core::int* v7 = let final core::String* #t48 = "x" in let final core::int* #t49 = super.{self::Base::[]}(#t48).{core::num::+}(self::getInt()){(core::num*) →* core::int*} in let final void #t50 = super.{self::Base::[]=}(#t48, #t49) in #t49;
+    core::num* v8 = let final core::String* #t51 = "x" in let final core::num* #t52 = super.{self::Base::[]}(#t51).{core::num::+}(self::getNum()){(core::num*) →* core::num*} in let final void #t53 = super.{self::Base::[]=}(#t51, #t52) in #t52;
+    core::double* v9 = let final core::String* #t54 = "x" in let final core::double* #t55 = super.{self::Base::[]}(#t54).{core::num::+}(self::getDouble()){(core::num*) →* core::double*} in let final void #t56 = super.{self::Base::[]=}(#t54, #t55) in #t55;
+    core::int* v10 = let final core::String* #t57 = "x" in let final core::int* #t58 = super.{self::Base::[]}(#t57).{core::num::+}(1){(core::num*) →* core::int*} in let final void #t59 = super.{self::Base::[]=}(#t57, #t58) in #t58;
+    core::int* v11 = let final core::String* #t60 = "x" in let final core::int* #t61 = super.{self::Base::[]}(#t60) in let final void #t62 = super.{self::Base::[]=}(#t60, #t61.{core::num::+}(1){(core::num*) →* core::int*}) in #t61;
+  }
+}
+abstract class Test3 extends self::Base<core::int*, core::double*> {
+  synthetic constructor •() → self::Test3*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    core::num* v2 = let final core::String* #t63 = "x" in let final core::num* #t64 = self::getNum() as{TypeError} core::double* in let final void #t65 = super.{self::Base::[]=}(#t63, #t64) in #t64;
+    core::double* v3 = let final core::String* #t66 = "x" in let final core::double* #t67 = self::getDouble() in let final void #t68 = super.{self::Base::[]=}(#t66, #t67) in #t67;
+    core::num* v5 = let final core::String* #t69 = "x" in let final core::int* #t70 = super.{self::Base::[]}(#t69) in #t70 == null ?{core::num*} let final core::num* #t71 = self::getNum() as{TypeError} core::double* in let final void #t72 = super.{self::Base::[]=}(#t69, #t71) in #t71 : #t70;
+    core::num* v6 = let final core::String* #t73 = "x" in let final core::int* #t74 = super.{self::Base::[]}(#t73) in #t74 == null ?{core::num*} let final core::double* #t75 = self::getDouble() in let final void #t76 = super.{self::Base::[]=}(#t73, #t75) in #t75 : #t74;
+    core::int* v7 = let final core::String* #t77 = "x" in let final core::int* #t78 = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart:106:31: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+            /*@target=num.+*/ += getInt();
+                              ^" in super.{self::Base::[]}(#t77).{core::num::+}(self::getInt()){(core::num*) →* core::int*} as{TypeError} core::double* in let final void #t79 = super.{self::Base::[]=}(#t77, #t78) in #t78;
+    core::num* v8 = let final core::String* #t80 = "x" in let final core::num* #t81 = super.{self::Base::[]}(#t80).{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::double* in let final void #t82 = super.{self::Base::[]=}(#t80, #t81) in #t81;
+    core::double* v9 = let final core::String* #t83 = "x" in let final core::double* #t84 = super.{self::Base::[]}(#t83).{core::num::+}(self::getDouble()){(core::num*) →* core::double*} in let final void #t85 = super.{self::Base::[]=}(#t83, #t84) in #t84;
+    core::int* v10 = let final core::String* #t86 = "x" in let final core::int* #t87 = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart:116:50: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+    var /*@ type=int* */ v10 = /*@target=num.+*/ ++super
+                                                 ^" in super.{self::Base::[]}(#t86).{core::num::+}(1){(core::num*) →* core::int*} as{TypeError} core::double* in let final void #t88 = super.{self::Base::[]=}(#t86, #t87) in #t87;
+    core::int* v11 = let final core::String* #t89 = "x" in let final core::int* #t90 = super.{self::Base::[]}(#t89) in let final void #t91 = super.{self::Base::[]=}(#t89, invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart:120:33: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+        ['x'] /*@target=num.+*/ ++;
+                                ^" in #t90.{core::num::+}(1){(core::num*) →* core::int*} as{TypeError} core::double*) in #t90;
+  }
+}
+abstract class Test4 extends self::Base<core::num*, core::int*> {
+  synthetic constructor •() → self::Test4*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    core::int* v1 = let final core::String* #t92 = "x" in let final core::int* #t93 = self::getInt() in let final void #t94 = super.{self::Base::[]=}(#t92, #t93) in #t93;
+    core::num* v2 = let final core::String* #t95 = "x" in let final core::num* #t96 = self::getNum() as{TypeError} core::int* in let final void #t97 = super.{self::Base::[]=}(#t95, #t96) in #t96;
+    core::num* v4 = let final core::String* #t98 = "x" in let final core::num* #t99 = super.{self::Base::[]}(#t98) in #t99 == null ?{core::num*} let final core::int* #t100 = self::getInt() in let final void #t101 = super.{self::Base::[]=}(#t98, #t100) in #t100 : #t99;
+    core::num* v5 = let final core::String* #t102 = "x" in let final core::num* #t103 = super.{self::Base::[]}(#t102) in #t103 == null ?{core::num*} let final core::num* #t104 = self::getNum() as{TypeError} core::int* in let final void #t105 = super.{self::Base::[]=}(#t102, #t104) in #t104 : #t103;
+    core::num* v7 = let final core::String* #t106 = "x" in let final core::num* #t107 = super.{self::Base::[]}(#t106).{core::num::+}(self::getInt()){(core::num*) →* core::num*} as{TypeError} core::int* in let final void #t108 = super.{self::Base::[]=}(#t106, #t107) in #t107;
+    core::num* v8 = let final core::String* #t109 = "x" in let final core::num* #t110 = super.{self::Base::[]}(#t109).{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::int* in let final void #t111 = super.{self::Base::[]=}(#t109, #t110) in #t110;
+    core::num* v10 = let final core::String* #t112 = "x" in let final core::num* #t113 = super.{self::Base::[]}(#t112).{core::num::+}(1){(core::num*) →* core::num*} as{TypeError} core::int* in let final void #t114 = super.{self::Base::[]=}(#t112, #t113) in #t113;
+    core::num* v11 = let final core::String* #t115 = "x" in let final core::num* #t116 = super.{self::Base::[]}(#t115) in let final void #t117 = super.{self::Base::[]=}(#t115, #t116.{core::num::+}(1){(core::num*) →* core::num*} as{TypeError} core::int*) in #t116;
+  }
+}
+abstract class Test5 extends self::Base<core::num*, core::num*> {
+  synthetic constructor •() → self::Test5*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    core::int* v1 = let final core::String* #t118 = "x" in let final core::int* #t119 = self::getInt() in let final void #t120 = super.{self::Base::[]=}(#t118, #t119) in #t119;
+    core::num* v2 = let final core::String* #t121 = "x" in let final core::num* #t122 = self::getNum() in let final void #t123 = super.{self::Base::[]=}(#t121, #t122) in #t122;
+    core::double* v3 = let final core::String* #t124 = "x" in let final core::double* #t125 = self::getDouble() in let final void #t126 = super.{self::Base::[]=}(#t124, #t125) in #t125;
+    core::num* v4 = let final core::String* #t127 = "x" in let final core::num* #t128 = super.{self::Base::[]}(#t127) in #t128 == null ?{core::num*} let final core::int* #t129 = self::getInt() in let final void #t130 = super.{self::Base::[]=}(#t127, #t129) in #t129 : #t128;
+    core::num* v5 = let final core::String* #t131 = "x" in let final core::num* #t132 = super.{self::Base::[]}(#t131) in #t132 == null ?{core::num*} let final core::num* #t133 = self::getNum() in let final void #t134 = super.{self::Base::[]=}(#t131, #t133) in #t133 : #t132;
+    core::num* v6 = let final core::String* #t135 = "x" in let final core::num* #t136 = super.{self::Base::[]}(#t135) in #t136 == null ?{core::num*} let final core::double* #t137 = self::getDouble() in let final void #t138 = super.{self::Base::[]=}(#t135, #t137) in #t137 : #t136;
+    core::num* v7 = let final core::String* #t139 = "x" in let final core::num* #t140 = super.{self::Base::[]}(#t139).{core::num::+}(self::getInt()){(core::num*) →* core::num*} in let final void #t141 = super.{self::Base::[]=}(#t139, #t140) in #t140;
+    core::num* v8 = let final core::String* #t142 = "x" in let final core::num* #t143 = super.{self::Base::[]}(#t142).{core::num::+}(self::getNum()){(core::num*) →* core::num*} in let final void #t144 = super.{self::Base::[]=}(#t142, #t143) in #t143;
+    core::num* v9 = let final core::String* #t145 = "x" in let final core::num* #t146 = super.{self::Base::[]}(#t145).{core::num::+}(self::getDouble()){(core::num*) →* core::num*} in let final void #t147 = super.{self::Base::[]=}(#t145, #t146) in #t146;
+    core::num* v10 = let final core::String* #t148 = "x" in let final core::num* #t149 = super.{self::Base::[]}(#t148).{core::num::+}(1){(core::num*) →* core::num*} in let final void #t150 = super.{self::Base::[]=}(#t148, #t149) in #t149;
+    core::num* v11 = let final core::String* #t151 = "x" in let final core::num* #t152 = super.{self::Base::[]}(#t151) in let final void #t153 = super.{self::Base::[]=}(#t151, #t152.{core::num::+}(1){(core::num*) →* core::num*}) in #t152;
+  }
+}
+abstract class Test6 extends self::Base<core::num*, core::double*> {
+  synthetic constructor •() → self::Test6*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    core::num* v2 = let final core::String* #t154 = "x" in let final core::num* #t155 = self::getNum() as{TypeError} core::double* in let final void #t156 = super.{self::Base::[]=}(#t154, #t155) in #t155;
+    core::double* v3 = let final core::String* #t157 = "x" in let final core::double* #t158 = self::getDouble() in let final void #t159 = super.{self::Base::[]=}(#t157, #t158) in #t158;
+    core::num* v5 = let final core::String* #t160 = "x" in let final core::num* #t161 = super.{self::Base::[]}(#t160) in #t161 == null ?{core::num*} let final core::num* #t162 = self::getNum() as{TypeError} core::double* in let final void #t163 = super.{self::Base::[]=}(#t160, #t162) in #t162 : #t161;
+    core::num* v6 = let final core::String* #t164 = "x" in let final core::num* #t165 = super.{self::Base::[]}(#t164) in #t165 == null ?{core::num*} let final core::double* #t166 = self::getDouble() in let final void #t167 = super.{self::Base::[]=}(#t164, #t166) in #t166 : #t165;
+    core::num* v7 = let final core::String* #t168 = "x" in let final core::num* #t169 = super.{self::Base::[]}(#t168).{core::num::+}(self::getInt()){(core::num*) →* core::num*} as{TypeError} core::double* in let final void #t170 = super.{self::Base::[]=}(#t168, #t169) in #t169;
+    core::num* v8 = let final core::String* #t171 = "x" in let final core::num* #t172 = super.{self::Base::[]}(#t171).{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::double* in let final void #t173 = super.{self::Base::[]=}(#t171, #t172) in #t172;
+    core::num* v9 = let final core::String* #t174 = "x" in let final core::num* #t175 = super.{self::Base::[]}(#t174).{core::num::+}(self::getDouble()){(core::num*) →* core::num*} as{TypeError} core::double* in let final void #t176 = super.{self::Base::[]=}(#t174, #t175) in #t175;
+    core::num* v10 = let final core::String* #t177 = "x" in let final core::num* #t178 = super.{self::Base::[]}(#t177).{core::num::+}(1){(core::num*) →* core::num*} as{TypeError} core::double* in let final void #t179 = super.{self::Base::[]=}(#t177, #t178) in #t178;
+    core::num* v11 = let final core::String* #t180 = "x" in let final core::num* #t181 = super.{self::Base::[]}(#t180) in let final void #t182 = super.{self::Base::[]=}(#t180, #t181.{core::num::+}(1){(core::num*) →* core::num*} as{TypeError} core::double*) in #t181;
+  }
+}
+abstract class Test7 extends self::Base<core::double*, core::int*> {
+  synthetic constructor •() → self::Test7*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    core::int* v1 = let final core::String* #t183 = "x" in let final core::int* #t184 = self::getInt() in let final void #t185 = super.{self::Base::[]=}(#t183, #t184) in #t184;
+    core::num* v2 = let final core::String* #t186 = "x" in let final core::num* #t187 = self::getNum() as{TypeError} core::int* in let final void #t188 = super.{self::Base::[]=}(#t186, #t187) in #t187;
+    core::num* v4 = let final core::String* #t189 = "x" in let final core::double* #t190 = super.{self::Base::[]}(#t189) in #t190 == null ?{core::num*} let final core::int* #t191 = self::getInt() in let final void #t192 = super.{self::Base::[]=}(#t189, #t191) in #t191 : #t190;
+    core::num* v5 = let final core::String* #t193 = "x" in let final core::double* #t194 = super.{self::Base::[]}(#t193) in #t194 == null ?{core::num*} let final core::num* #t195 = self::getNum() as{TypeError} core::int* in let final void #t196 = super.{self::Base::[]=}(#t193, #t195) in #t195 : #t194;
+    core::double* v7 = let final core::String* #t197 = "x" in let final core::double* #t198 = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart:244:34: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+            /*@target=double.+*/ += getInt();
+                                 ^" in super.{self::Base::[]}(#t197).{core::double::+}(self::getInt()){(core::num*) →* core::double*} as{TypeError} core::int* in let final void #t199 = super.{self::Base::[]=}(#t197, #t198) in #t198;
+    core::double* v8 = let final core::String* #t200 = "x" in let final core::double* #t201 = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart:248:34: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+            /*@target=double.+*/ += getNum();
+                                 ^" in super.{self::Base::[]}(#t200).{core::double::+}(self::getNum()){(core::num*) →* core::double*} as{TypeError} core::int* in let final void #t202 = super.{self::Base::[]=}(#t200, #t201) in #t201;
+    core::double* v10 = let final core::String* #t203 = "x" in let final core::double* #t204 = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart:250:56: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+    var /*@ type=double* */ v10 = /*@target=double.+*/ ++super
+                                                       ^" in super.{self::Base::[]}(#t203).{core::double::+}(1){(core::num*) →* core::double*} as{TypeError} core::int* in let final void #t205 = super.{self::Base::[]=}(#t203, #t204) in #t204;
+    core::double* v11 = let final core::String* #t206 = "x" in let final core::double* #t207 = super.{self::Base::[]}(#t206) in let final void #t208 = super.{self::Base::[]=}(#t206, invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_super_upwards.dart:254:36: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+        ['x'] /*@target=double.+*/ ++;
+                                   ^" in #t207.{core::double::+}(1){(core::num*) →* core::double*} as{TypeError} core::int*) in #t207;
+  }
+}
+abstract class Test8 extends self::Base<core::double*, core::num*> {
+  synthetic constructor •() → self::Test8*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    core::int* v1 = let final core::String* #t209 = "x" in let final core::int* #t210 = self::getInt() in let final void #t211 = super.{self::Base::[]=}(#t209, #t210) in #t210;
+    core::num* v2 = let final core::String* #t212 = "x" in let final core::num* #t213 = self::getNum() in let final void #t214 = super.{self::Base::[]=}(#t212, #t213) in #t213;
+    core::double* v3 = let final core::String* #t215 = "x" in let final core::double* #t216 = self::getDouble() in let final void #t217 = super.{self::Base::[]=}(#t215, #t216) in #t216;
+    core::num* v4 = let final core::String* #t218 = "x" in let final core::double* #t219 = super.{self::Base::[]}(#t218) in #t219 == null ?{core::num*} let final core::int* #t220 = self::getInt() in let final void #t221 = super.{self::Base::[]=}(#t218, #t220) in #t220 : #t219;
+    core::num* v5 = let final core::String* #t222 = "x" in let final core::double* #t223 = super.{self::Base::[]}(#t222) in #t223 == null ?{core::num*} let final core::num* #t224 = self::getNum() in let final void #t225 = super.{self::Base::[]=}(#t222, #t224) in #t224 : #t223;
+    core::double* v6 = let final core::String* #t226 = "x" in let final core::double* #t227 = super.{self::Base::[]}(#t226) in #t227 == null ?{core::double*} let final core::double* #t228 = self::getDouble() in let final void #t229 = super.{self::Base::[]=}(#t226, #t228) in #t228 : #t227;
+    core::double* v7 = let final core::String* #t230 = "x" in let final core::double* #t231 = super.{self::Base::[]}(#t230).{core::double::+}(self::getInt()){(core::num*) →* core::double*} in let final void #t232 = super.{self::Base::[]=}(#t230, #t231) in #t231;
+    core::double* v8 = let final core::String* #t233 = "x" in let final core::double* #t234 = super.{self::Base::[]}(#t233).{core::double::+}(self::getNum()){(core::num*) →* core::double*} in let final void #t235 = super.{self::Base::[]=}(#t233, #t234) in #t234;
+    core::double* v9 = let final core::String* #t236 = "x" in let final core::double* #t237 = super.{self::Base::[]}(#t236).{core::double::+}(self::getDouble()){(core::num*) →* core::double*} in let final void #t238 = super.{self::Base::[]=}(#t236, #t237) in #t237;
+    core::double* v10 = let final core::String* #t239 = "x" in let final core::double* #t240 = super.{self::Base::[]}(#t239).{core::double::+}(1){(core::num*) →* core::double*} in let final void #t241 = super.{self::Base::[]=}(#t239, #t240) in #t240;
+    core::double* v11 = let final core::String* #t242 = "x" in let final core::double* #t243 = super.{self::Base::[]}(#t242) in let final void #t244 = super.{self::Base::[]=}(#t242, #t243.{core::double::+}(1){(core::num*) →* core::double*}) in #t243;
+  }
+}
+abstract class Test9 extends self::Base<core::double*, core::double*> {
+  synthetic constructor •() → self::Test9*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    core::num* v2 = let final core::String* #t245 = "x" in let final core::num* #t246 = self::getNum() as{TypeError} core::double* in let final void #t247 = super.{self::Base::[]=}(#t245, #t246) in #t246;
+    core::double* v3 = let final core::String* #t248 = "x" in let final core::double* #t249 = self::getDouble() in let final void #t250 = super.{self::Base::[]=}(#t248, #t249) in #t249;
+    core::num* v5 = let final core::String* #t251 = "x" in let final core::double* #t252 = super.{self::Base::[]}(#t251) in #t252 == null ?{core::num*} let final core::num* #t253 = self::getNum() as{TypeError} core::double* in let final void #t254 = super.{self::Base::[]=}(#t251, #t253) in #t253 : #t252;
+    core::double* v6 = let final core::String* #t255 = "x" in let final core::double* #t256 = super.{self::Base::[]}(#t255) in #t256 == null ?{core::double*} let final core::double* #t257 = self::getDouble() in let final void #t258 = super.{self::Base::[]=}(#t255, #t257) in #t257 : #t256;
+    core::double* v7 = let final core::String* #t259 = "x" in let final core::double* #t260 = super.{self::Base::[]}(#t259).{core::double::+}(self::getInt()){(core::num*) →* core::double*} in let final void #t261 = super.{self::Base::[]=}(#t259, #t260) in #t260;
+    core::double* v8 = let final core::String* #t262 = "x" in let final core::double* #t263 = super.{self::Base::[]}(#t262).{core::double::+}(self::getNum()){(core::num*) →* core::double*} in let final void #t264 = super.{self::Base::[]=}(#t262, #t263) in #t263;
+    core::double* v9 = let final core::String* #t265 = "x" in let final core::double* #t266 = super.{self::Base::[]}(#t265).{core::double::+}(self::getDouble()){(core::num*) →* core::double*} in let final void #t267 = super.{self::Base::[]=}(#t265, #t266) in #t266;
+    core::double* v10 = let final core::String* #t268 = "x" in let final core::double* #t269 = super.{self::Base::[]}(#t268).{core::double::+}(1){(core::num*) →* core::double*} in let final void #t270 = super.{self::Base::[]=}(#t268, #t269) in #t269;
+    core::double* v11 = let final core::String* #t271 = "x" in let final core::double* #t272 = super.{self::Base::[]}(#t271) in let final void #t273 = super.{self::Base::[]=}(#t271, #t272.{core::double::+}(1){(core::num*) →* core::double*}) in #t272;
+  }
+}
+static method getInt() → core::int*
+  return 0;
+static method getNum() → core::num*
+  return 0;
+static method getDouble() → core::double*
+  return 0.0;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_index_this.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_index_this.dart.weak.modular.expect
new file mode 100644
index 0000000..0202be1
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_index_this.dart.weak.modular.expect
@@ -0,0 +1,89 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Index extends core::Object {
+  synthetic constructor •() → self::Index*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class Test extends core::Object {
+  synthetic constructor •() → self::Test*
+    : super core::Object::•()
+    ;
+  operator [](self::Index* i) → self::B*
+    return null;
+  operator []=(self::Index* i, self::B* v) → void {}
+  method test() → void {
+    this.{self::Test::[]=}(self::f<self::Index*>(), self::f<self::B*>()){(self::Index*, self::B*) →* void};
+    let final self::Index* #t1 = self::f<self::Index*>() in this.{self::Test::[]}(#t1){(self::Index*) →* self::B*} == null ?{self::B*} this.{self::Test::[]=}(#t1, self::f<self::B*>()){(self::Index*, self::B*) →* void} : null;
+    let final self::Index* #t2 = self::f<self::Index*>() in this.{self::Test::[]=}(#t2, this.{self::Test::[]}(#t2){(self::Index*) →* self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*){(self::Index*, self::B*) →* void};
+    let final self::Index* #t3 = self::f<self::Index*>() in this.{self::Test::[]=}(#t3, this.{self::Test::[]}(#t3){(self::Index*) →* self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*}){(self::Index*, self::B*) →* void};
+    let final self::Index* #t4 = self::f<self::Index*>() in this.{self::Test::[]=}(#t4, this.{self::Test::[]}(#t4){(self::Index*) →* self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*}){(self::Index*, self::B*) →* void};
+    let final self::Index* #t5 = self::f<self::Index*>() in let final self::B* #t6 = this.{self::Test::[]}(#t5){(self::Index*) →* self::B*}.{self::B::-}(1){(core::int*) →* self::B*} in let final void #t7 = this.{self::Test::[]=}(#t5, #t6){(self::Index*, self::B*) →* void} in #t6;
+    let final self::Index* #t8 = self::f<self::Index*>() in this.{self::Test::[]=}(#t8, this.{self::Test::[]}(#t8){(self::Index*) →* self::B*}.{self::B::-}(1){(core::int*) →* self::B*}){(self::Index*, self::B*) →* void};
+    self::B* v1 = let final self::Index* #t9 = self::f<self::Index*>() in let final self::B* #t10 = self::f<self::B*>() in let final void #t11 = this.{self::Test::[]=}(#t9, #t10){(self::Index*, self::B*) →* void} in #t10;
+    self::B* v2 = let final self::Index* #t12 = self::f<self::Index*>() in let final self::B* #t13 = this.{self::Test::[]}(#t12){(self::Index*) →* self::B*} in #t13 == null ?{self::B*} let final self::B* #t14 = self::f<self::B*>() in let final void #t15 = this.{self::Test::[]=}(#t12, #t14){(self::Index*, self::B*) →* void} in #t14 : #t13;
+    self::A* v3 = let final self::Index* #t16 = self::f<self::Index*>() in let final self::A* #t17 = this.{self::Test::[]}(#t16){(self::Index*) →* self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B* in let final void #t18 = this.{self::Test::[]=}(#t16, #t17){(self::Index*, self::B*) →* void} in #t17;
+    self::B* v4 = let final self::Index* #t19 = self::f<self::Index*>() in let final self::B* #t20 = this.{self::Test::[]}(#t19){(self::Index*) →* self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*} in let final void #t21 = this.{self::Test::[]=}(#t19, #t20){(self::Index*, self::B*) →* void} in #t20;
+    self::C* v5 = let final self::Index* #t22 = self::f<self::Index*>() in let final self::C* #t23 = this.{self::Test::[]}(#t22){(self::Index*) →* self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*} in let final void #t24 = this.{self::Test::[]=}(#t22, #t23){(self::Index*, self::B*) →* void} in #t23;
+    self::B* v6 = let final self::Index* #t25 = self::f<self::Index*>() in let final self::B* #t26 = this.{self::Test::[]}(#t25){(self::Index*) →* self::B*}.{self::B::-}(1){(core::int*) →* self::B*} in let final void #t27 = this.{self::Test::[]=}(#t25, #t26){(self::Index*, self::B*) →* void} in #t26;
+    self::B* v7 = let final self::Index* #t28 = self::f<self::Index*>() in let final self::B* #t29 = this.{self::Test::[]}(#t28){(self::Index*) →* self::B*} in let final void #t30 = this.{self::Test::[]=}(#t28, #t29.{self::B::-}(1){(core::int*) →* self::B*}){(self::Index*, self::B*) →* void} in #t29;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..99a0822
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart.weak.modular.expect
@@ -0,0 +1,311 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart:109:27: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+//         /*@target=num.+*/ += getInt();
+//                           ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart:119:50: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+//     var /*@ type=int* */ v10 = /*@target=num.+*/ ++this
+//                                                  ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart:124:27: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+//         /*@target=num.+*/ ++;
+//                           ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart:264:30: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//         /*@target=double.+*/ += getInt();
+//                              ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart:268:30: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//         /*@target=double.+*/ += getNum();
+//                              ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart:270:56: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//     var /*@ type=double* */ v10 = /*@target=double.+*/ ++this
+//                                                        ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart:275:30: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//         /*@target=double.+*/ ++;
+//                              ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Test1 extends core::Object {
+  synthetic constructor •() → self::Test1*
+    : super core::Object::•()
+    ;
+  abstract operator [](core::String* s) → core::int*;
+  abstract operator []=(core::String* s, core::int* v) → void;
+  method test() → void {
+    core::int* v1 = let final core::String* #t1 = "x" in let final core::int* #t2 = self::getInt() in let final void #t3 = this.{self::Test1::[]=}(#t1, #t2){(core::String*, core::int*) →* void} in #t2;
+    core::num* v2 = let final core::String* #t4 = "x" in let final core::num* #t5 = self::getNum() as{TypeError} core::int* in let final void #t6 = this.{self::Test1::[]=}(#t4, #t5){(core::String*, core::int*) →* void} in #t5;
+    core::int* v4 = let final core::String* #t7 = "x" in let final core::int* #t8 = this.{self::Test1::[]}(#t7){(core::String*) →* core::int*} in #t8 == null ?{core::int*} let final core::int* #t9 = self::getInt() in let final void #t10 = this.{self::Test1::[]=}(#t7, #t9){(core::String*, core::int*) →* void} in #t9 : #t8;
+    core::num* v5 = let final core::String* #t11 = "x" in let final core::int* #t12 = this.{self::Test1::[]}(#t11){(core::String*) →* core::int*} in #t12 == null ?{core::num*} let final core::num* #t13 = self::getNum() as{TypeError} core::int* in let final void #t14 = this.{self::Test1::[]=}(#t11, #t13){(core::String*, core::int*) →* void} in #t13 : #t12;
+    core::int* v7 = let final core::String* #t15 = "x" in let final core::int* #t16 = this.{self::Test1::[]}(#t15){(core::String*) →* core::int*}.{core::num::+}(self::getInt()){(core::num*) →* core::int*} in let final void #t17 = this.{self::Test1::[]=}(#t15, #t16){(core::String*, core::int*) →* void} in #t16;
+    core::num* v8 = let final core::String* #t18 = "x" in let final core::num* #t19 = this.{self::Test1::[]}(#t18){(core::String*) →* core::int*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::int* in let final void #t20 = this.{self::Test1::[]=}(#t18, #t19){(core::String*, core::int*) →* void} in #t19;
+    core::int* v10 = let final core::String* #t21 = "x" in let final core::int* #t22 = this.{self::Test1::[]}(#t21){(core::String*) →* core::int*}.{core::num::+}(1){(core::num*) →* core::int*} in let final void #t23 = this.{self::Test1::[]=}(#t21, #t22){(core::String*, core::int*) →* void} in #t22;
+    core::int* v11 = let final core::String* #t24 = "x" in let final core::int* #t25 = this.{self::Test1::[]}(#t24){(core::String*) →* core::int*} in let final void #t26 = this.{self::Test1::[]=}(#t24, #t25.{core::num::+}(1){(core::num*) →* core::int*}){(core::String*, core::int*) →* void} in #t25;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Test2 extends core::Object {
+  synthetic constructor •() → self::Test2*
+    : super core::Object::•()
+    ;
+  abstract operator [](core::String* s) → core::int*;
+  abstract operator []=(core::String* s, core::num* v) → void;
+  method test() → void {
+    core::int* v1 = let final core::String* #t27 = "x" in let final core::int* #t28 = self::getInt() in let final void #t29 = this.{self::Test2::[]=}(#t27, #t28){(core::String*, core::num*) →* void} in #t28;
+    core::num* v2 = let final core::String* #t30 = "x" in let final core::num* #t31 = self::getNum() in let final void #t32 = this.{self::Test2::[]=}(#t30, #t31){(core::String*, core::num*) →* void} in #t31;
+    core::double* v3 = let final core::String* #t33 = "x" in let final core::double* #t34 = self::getDouble() in let final void #t35 = this.{self::Test2::[]=}(#t33, #t34){(core::String*, core::num*) →* void} in #t34;
+    core::int* v4 = let final core::String* #t36 = "x" in let final core::int* #t37 = this.{self::Test2::[]}(#t36){(core::String*) →* core::int*} in #t37 == null ?{core::int*} let final core::int* #t38 = self::getInt() in let final void #t39 = this.{self::Test2::[]=}(#t36, #t38){(core::String*, core::num*) →* void} in #t38 : #t37;
+    core::num* v5 = let final core::String* #t40 = "x" in let final core::int* #t41 = this.{self::Test2::[]}(#t40){(core::String*) →* core::int*} in #t41 == null ?{core::num*} let final core::num* #t42 = self::getNum() in let final void #t43 = this.{self::Test2::[]=}(#t40, #t42){(core::String*, core::num*) →* void} in #t42 : #t41;
+    core::num* v6 = let final core::String* #t44 = "x" in let final core::int* #t45 = this.{self::Test2::[]}(#t44){(core::String*) →* core::int*} in #t45 == null ?{core::num*} let final core::double* #t46 = self::getDouble() in let final void #t47 = this.{self::Test2::[]=}(#t44, #t46){(core::String*, core::num*) →* void} in #t46 : #t45;
+    core::int* v7 = let final core::String* #t48 = "x" in let final core::int* #t49 = this.{self::Test2::[]}(#t48){(core::String*) →* core::int*}.{core::num::+}(self::getInt()){(core::num*) →* core::int*} in let final void #t50 = this.{self::Test2::[]=}(#t48, #t49){(core::String*, core::num*) →* void} in #t49;
+    core::num* v8 = let final core::String* #t51 = "x" in let final core::num* #t52 = this.{self::Test2::[]}(#t51){(core::String*) →* core::int*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} in let final void #t53 = this.{self::Test2::[]=}(#t51, #t52){(core::String*, core::num*) →* void} in #t52;
+    core::double* v9 = let final core::String* #t54 = "x" in let final core::double* #t55 = this.{self::Test2::[]}(#t54){(core::String*) →* core::int*}.{core::num::+}(self::getDouble()){(core::num*) →* core::double*} in let final void #t56 = this.{self::Test2::[]=}(#t54, #t55){(core::String*, core::num*) →* void} in #t55;
+    core::int* v10 = let final core::String* #t57 = "x" in let final core::int* #t58 = this.{self::Test2::[]}(#t57){(core::String*) →* core::int*}.{core::num::+}(1){(core::num*) →* core::int*} in let final void #t59 = this.{self::Test2::[]=}(#t57, #t58){(core::String*, core::num*) →* void} in #t58;
+    core::int* v11 = let final core::String* #t60 = "x" in let final core::int* #t61 = this.{self::Test2::[]}(#t60){(core::String*) →* core::int*} in let final void #t62 = this.{self::Test2::[]=}(#t60, #t61.{core::num::+}(1){(core::num*) →* core::int*}){(core::String*, core::num*) →* void} in #t61;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Test3 extends core::Object {
+  synthetic constructor •() → self::Test3*
+    : super core::Object::•()
+    ;
+  abstract operator [](core::String* s) → core::int*;
+  abstract operator []=(core::String* s, core::double* v) → void;
+  method test() → void {
+    core::num* v2 = let final core::String* #t63 = "x" in let final core::num* #t64 = self::getNum() as{TypeError} core::double* in let final void #t65 = this.{self::Test3::[]=}(#t63, #t64){(core::String*, core::double*) →* void} in #t64;
+    core::double* v3 = let final core::String* #t66 = "x" in let final core::double* #t67 = self::getDouble() in let final void #t68 = this.{self::Test3::[]=}(#t66, #t67){(core::String*, core::double*) →* void} in #t67;
+    core::num* v5 = let final core::String* #t69 = "x" in let final core::int* #t70 = this.{self::Test3::[]}(#t69){(core::String*) →* core::int*} in #t70 == null ?{core::num*} let final core::num* #t71 = self::getNum() as{TypeError} core::double* in let final void #t72 = this.{self::Test3::[]=}(#t69, #t71){(core::String*, core::double*) →* void} in #t71 : #t70;
+    core::num* v6 = let final core::String* #t73 = "x" in let final core::int* #t74 = this.{self::Test3::[]}(#t73){(core::String*) →* core::int*} in #t74 == null ?{core::num*} let final core::double* #t75 = self::getDouble() in let final void #t76 = this.{self::Test3::[]=}(#t73, #t75){(core::String*, core::double*) →* void} in #t75 : #t74;
+    core::int* v7 = let final core::String* #t77 = "x" in let final core::int* #t78 = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart:109:27: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+        /*@target=num.+*/ += getInt();
+                          ^" in this.{self::Test3::[]}(#t77){(core::String*) →* core::int*}.{core::num::+}(self::getInt()){(core::num*) →* core::int*} as{TypeError} core::double* in let final void #t79 = this.{self::Test3::[]=}(#t77, #t78){(core::String*, core::double*) →* void} in #t78;
+    core::num* v8 = let final core::String* #t80 = "x" in let final core::num* #t81 = this.{self::Test3::[]}(#t80){(core::String*) →* core::int*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::double* in let final void #t82 = this.{self::Test3::[]=}(#t80, #t81){(core::String*, core::double*) →* void} in #t81;
+    core::double* v9 = let final core::String* #t83 = "x" in let final core::double* #t84 = this.{self::Test3::[]}(#t83){(core::String*) →* core::int*}.{core::num::+}(self::getDouble()){(core::num*) →* core::double*} in let final void #t85 = this.{self::Test3::[]=}(#t83, #t84){(core::String*, core::double*) →* void} in #t84;
+    core::int* v10 = let final core::String* #t86 = "x" in let final core::int* #t87 = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart:119:50: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+    var /*@ type=int* */ v10 = /*@target=num.+*/ ++this
+                                                 ^" in this.{self::Test3::[]}(#t86){(core::String*) →* core::int*}.{core::num::+}(1){(core::num*) →* core::int*} as{TypeError} core::double* in let final void #t88 = this.{self::Test3::[]=}(#t86, #t87){(core::String*, core::double*) →* void} in #t87;
+    core::int* v11 = let final core::String* #t89 = "x" in let final core::int* #t90 = this.{self::Test3::[]}(#t89){(core::String*) →* core::int*} in let final void #t91 = this.{self::Test3::[]=}(#t89, invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart:124:27: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+        /*@target=num.+*/ ++;
+                          ^" in #t90.{core::num::+}(1){(core::num*) →* core::int*} as{TypeError} core::double*){(core::String*, core::double*) →* void} in #t90;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Test4 extends core::Object {
+  synthetic constructor •() → self::Test4*
+    : super core::Object::•()
+    ;
+  abstract operator [](core::String* s) → core::num*;
+  abstract operator []=(core::String* s, core::int* v) → void;
+  method test() → void {
+    core::int* v1 = let final core::String* #t92 = "x" in let final core::int* #t93 = self::getInt() in let final void #t94 = this.{self::Test4::[]=}(#t92, #t93){(core::String*, core::int*) →* void} in #t93;
+    core::num* v2 = let final core::String* #t95 = "x" in let final core::num* #t96 = self::getNum() as{TypeError} core::int* in let final void #t97 = this.{self::Test4::[]=}(#t95, #t96){(core::String*, core::int*) →* void} in #t96;
+    core::num* v4 = let final core::String* #t98 = "x" in let final core::num* #t99 = this.{self::Test4::[]}(#t98){(core::String*) →* core::num*} in #t99 == null ?{core::num*} let final core::int* #t100 = self::getInt() in let final void #t101 = this.{self::Test4::[]=}(#t98, #t100){(core::String*, core::int*) →* void} in #t100 : #t99;
+    core::num* v5 = let final core::String* #t102 = "x" in let final core::num* #t103 = this.{self::Test4::[]}(#t102){(core::String*) →* core::num*} in #t103 == null ?{core::num*} let final core::num* #t104 = self::getNum() as{TypeError} core::int* in let final void #t105 = this.{self::Test4::[]=}(#t102, #t104){(core::String*, core::int*) →* void} in #t104 : #t103;
+    core::num* v7 = let final core::String* #t106 = "x" in let final core::num* #t107 = this.{self::Test4::[]}(#t106){(core::String*) →* core::num*}.{core::num::+}(self::getInt()){(core::num*) →* core::num*} as{TypeError} core::int* in let final void #t108 = this.{self::Test4::[]=}(#t106, #t107){(core::String*, core::int*) →* void} in #t107;
+    core::num* v8 = let final core::String* #t109 = "x" in let final core::num* #t110 = this.{self::Test4::[]}(#t109){(core::String*) →* core::num*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::int* in let final void #t111 = this.{self::Test4::[]=}(#t109, #t110){(core::String*, core::int*) →* void} in #t110;
+    core::num* v10 = let final core::String* #t112 = "x" in let final core::num* #t113 = this.{self::Test4::[]}(#t112){(core::String*) →* core::num*}.{core::num::+}(1){(core::num*) →* core::num*} as{TypeError} core::int* in let final void #t114 = this.{self::Test4::[]=}(#t112, #t113){(core::String*, core::int*) →* void} in #t113;
+    core::num* v11 = let final core::String* #t115 = "x" in let final core::num* #t116 = this.{self::Test4::[]}(#t115){(core::String*) →* core::num*} in let final void #t117 = this.{self::Test4::[]=}(#t115, #t116.{core::num::+}(1){(core::num*) →* core::num*} as{TypeError} core::int*){(core::String*, core::int*) →* void} in #t116;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Test5 extends core::Object {
+  synthetic constructor •() → self::Test5*
+    : super core::Object::•()
+    ;
+  abstract operator [](core::String* s) → core::num*;
+  abstract operator []=(core::String* s, core::num* v) → void;
+  method test() → void {
+    core::int* v1 = let final core::String* #t118 = "x" in let final core::int* #t119 = self::getInt() in let final void #t120 = this.{self::Test5::[]=}(#t118, #t119){(core::String*, core::num*) →* void} in #t119;
+    core::num* v2 = let final core::String* #t121 = "x" in let final core::num* #t122 = self::getNum() in let final void #t123 = this.{self::Test5::[]=}(#t121, #t122){(core::String*, core::num*) →* void} in #t122;
+    core::double* v3 = let final core::String* #t124 = "x" in let final core::double* #t125 = self::getDouble() in let final void #t126 = this.{self::Test5::[]=}(#t124, #t125){(core::String*, core::num*) →* void} in #t125;
+    core::num* v4 = let final core::String* #t127 = "x" in let final core::num* #t128 = this.{self::Test5::[]}(#t127){(core::String*) →* core::num*} in #t128 == null ?{core::num*} let final core::int* #t129 = self::getInt() in let final void #t130 = this.{self::Test5::[]=}(#t127, #t129){(core::String*, core::num*) →* void} in #t129 : #t128;
+    core::num* v5 = let final core::String* #t131 = "x" in let final core::num* #t132 = this.{self::Test5::[]}(#t131){(core::String*) →* core::num*} in #t132 == null ?{core::num*} let final core::num* #t133 = self::getNum() in let final void #t134 = this.{self::Test5::[]=}(#t131, #t133){(core::String*, core::num*) →* void} in #t133 : #t132;
+    core::num* v6 = let final core::String* #t135 = "x" in let final core::num* #t136 = this.{self::Test5::[]}(#t135){(core::String*) →* core::num*} in #t136 == null ?{core::num*} let final core::double* #t137 = self::getDouble() in let final void #t138 = this.{self::Test5::[]=}(#t135, #t137){(core::String*, core::num*) →* void} in #t137 : #t136;
+    core::num* v7 = let final core::String* #t139 = "x" in let final core::num* #t140 = this.{self::Test5::[]}(#t139){(core::String*) →* core::num*}.{core::num::+}(self::getInt()){(core::num*) →* core::num*} in let final void #t141 = this.{self::Test5::[]=}(#t139, #t140){(core::String*, core::num*) →* void} in #t140;
+    core::num* v8 = let final core::String* #t142 = "x" in let final core::num* #t143 = this.{self::Test5::[]}(#t142){(core::String*) →* core::num*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} in let final void #t144 = this.{self::Test5::[]=}(#t142, #t143){(core::String*, core::num*) →* void} in #t143;
+    core::num* v9 = let final core::String* #t145 = "x" in let final core::num* #t146 = this.{self::Test5::[]}(#t145){(core::String*) →* core::num*}.{core::num::+}(self::getDouble()){(core::num*) →* core::num*} in let final void #t147 = this.{self::Test5::[]=}(#t145, #t146){(core::String*, core::num*) →* void} in #t146;
+    core::num* v10 = let final core::String* #t148 = "x" in let final core::num* #t149 = this.{self::Test5::[]}(#t148){(core::String*) →* core::num*}.{core::num::+}(1){(core::num*) →* core::num*} in let final void #t150 = this.{self::Test5::[]=}(#t148, #t149){(core::String*, core::num*) →* void} in #t149;
+    core::num* v11 = let final core::String* #t151 = "x" in let final core::num* #t152 = this.{self::Test5::[]}(#t151){(core::String*) →* core::num*} in let final void #t153 = this.{self::Test5::[]=}(#t151, #t152.{core::num::+}(1){(core::num*) →* core::num*}){(core::String*, core::num*) →* void} in #t152;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Test6 extends core::Object {
+  synthetic constructor •() → self::Test6*
+    : super core::Object::•()
+    ;
+  abstract operator [](core::String* s) → core::num*;
+  abstract operator []=(core::String* s, core::double* v) → void;
+  method test() → void {
+    core::num* v2 = let final core::String* #t154 = "x" in let final core::num* #t155 = self::getNum() as{TypeError} core::double* in let final void #t156 = this.{self::Test6::[]=}(#t154, #t155){(core::String*, core::double*) →* void} in #t155;
+    core::double* v3 = let final core::String* #t157 = "x" in let final core::double* #t158 = self::getDouble() in let final void #t159 = this.{self::Test6::[]=}(#t157, #t158){(core::String*, core::double*) →* void} in #t158;
+    core::num* v5 = let final core::String* #t160 = "x" in let final core::num* #t161 = this.{self::Test6::[]}(#t160){(core::String*) →* core::num*} in #t161 == null ?{core::num*} let final core::num* #t162 = self::getNum() as{TypeError} core::double* in let final void #t163 = this.{self::Test6::[]=}(#t160, #t162){(core::String*, core::double*) →* void} in #t162 : #t161;
+    core::num* v6 = let final core::String* #t164 = "x" in let final core::num* #t165 = this.{self::Test6::[]}(#t164){(core::String*) →* core::num*} in #t165 == null ?{core::num*} let final core::double* #t166 = self::getDouble() in let final void #t167 = this.{self::Test6::[]=}(#t164, #t166){(core::String*, core::double*) →* void} in #t166 : #t165;
+    core::num* v7 = let final core::String* #t168 = "x" in let final core::num* #t169 = this.{self::Test6::[]}(#t168){(core::String*) →* core::num*}.{core::num::+}(self::getInt()){(core::num*) →* core::num*} as{TypeError} core::double* in let final void #t170 = this.{self::Test6::[]=}(#t168, #t169){(core::String*, core::double*) →* void} in #t169;
+    core::num* v8 = let final core::String* #t171 = "x" in let final core::num* #t172 = this.{self::Test6::[]}(#t171){(core::String*) →* core::num*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::double* in let final void #t173 = this.{self::Test6::[]=}(#t171, #t172){(core::String*, core::double*) →* void} in #t172;
+    core::num* v9 = let final core::String* #t174 = "x" in let final core::num* #t175 = this.{self::Test6::[]}(#t174){(core::String*) →* core::num*}.{core::num::+}(self::getDouble()){(core::num*) →* core::num*} as{TypeError} core::double* in let final void #t176 = this.{self::Test6::[]=}(#t174, #t175){(core::String*, core::double*) →* void} in #t175;
+    core::num* v10 = let final core::String* #t177 = "x" in let final core::num* #t178 = this.{self::Test6::[]}(#t177){(core::String*) →* core::num*}.{core::num::+}(1){(core::num*) →* core::num*} as{TypeError} core::double* in let final void #t179 = this.{self::Test6::[]=}(#t177, #t178){(core::String*, core::double*) →* void} in #t178;
+    core::num* v11 = let final core::String* #t180 = "x" in let final core::num* #t181 = this.{self::Test6::[]}(#t180){(core::String*) →* core::num*} in let final void #t182 = this.{self::Test6::[]=}(#t180, #t181.{core::num::+}(1){(core::num*) →* core::num*} as{TypeError} core::double*){(core::String*, core::double*) →* void} in #t181;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Test7 extends core::Object {
+  synthetic constructor •() → self::Test7*
+    : super core::Object::•()
+    ;
+  abstract operator [](core::String* s) → core::double*;
+  abstract operator []=(core::String* s, core::int* v) → void;
+  method test() → void {
+    core::int* v1 = let final core::String* #t183 = "x" in let final core::int* #t184 = self::getInt() in let final void #t185 = this.{self::Test7::[]=}(#t183, #t184){(core::String*, core::int*) →* void} in #t184;
+    core::num* v2 = let final core::String* #t186 = "x" in let final core::num* #t187 = self::getNum() as{TypeError} core::int* in let final void #t188 = this.{self::Test7::[]=}(#t186, #t187){(core::String*, core::int*) →* void} in #t187;
+    core::num* v4 = let final core::String* #t189 = "x" in let final core::double* #t190 = this.{self::Test7::[]}(#t189){(core::String*) →* core::double*} in #t190 == null ?{core::num*} let final core::int* #t191 = self::getInt() in let final void #t192 = this.{self::Test7::[]=}(#t189, #t191){(core::String*, core::int*) →* void} in #t191 : #t190;
+    core::num* v5 = let final core::String* #t193 = "x" in let final core::double* #t194 = this.{self::Test7::[]}(#t193){(core::String*) →* core::double*} in #t194 == null ?{core::num*} let final core::num* #t195 = self::getNum() as{TypeError} core::int* in let final void #t196 = this.{self::Test7::[]=}(#t193, #t195){(core::String*, core::int*) →* void} in #t195 : #t194;
+    core::double* v7 = let final core::String* #t197 = "x" in let final core::double* #t198 = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart:264:30: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+        /*@target=double.+*/ += getInt();
+                             ^" in this.{self::Test7::[]}(#t197){(core::String*) →* core::double*}.{core::double::+}(self::getInt()){(core::num*) →* core::double*} as{TypeError} core::int* in let final void #t199 = this.{self::Test7::[]=}(#t197, #t198){(core::String*, core::int*) →* void} in #t198;
+    core::double* v8 = let final core::String* #t200 = "x" in let final core::double* #t201 = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart:268:30: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+        /*@target=double.+*/ += getNum();
+                             ^" in this.{self::Test7::[]}(#t200){(core::String*) →* core::double*}.{core::double::+}(self::getNum()){(core::num*) →* core::double*} as{TypeError} core::int* in let final void #t202 = this.{self::Test7::[]=}(#t200, #t201){(core::String*, core::int*) →* void} in #t201;
+    core::double* v10 = let final core::String* #t203 = "x" in let final core::double* #t204 = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart:270:56: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+    var /*@ type=double* */ v10 = /*@target=double.+*/ ++this
+                                                       ^" in this.{self::Test7::[]}(#t203){(core::String*) →* core::double*}.{core::double::+}(1){(core::num*) →* core::double*} as{TypeError} core::int* in let final void #t205 = this.{self::Test7::[]=}(#t203, #t204){(core::String*, core::int*) →* void} in #t204;
+    core::double* v11 = let final core::String* #t206 = "x" in let final core::double* #t207 = this.{self::Test7::[]}(#t206){(core::String*) →* core::double*} in let final void #t208 = this.{self::Test7::[]=}(#t206, invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_this_upwards.dart:275:30: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+        /*@target=double.+*/ ++;
+                             ^" in #t207.{core::double::+}(1){(core::num*) →* core::double*} as{TypeError} core::int*){(core::String*, core::int*) →* void} in #t207;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Test8 extends core::Object {
+  synthetic constructor •() → self::Test8*
+    : super core::Object::•()
+    ;
+  abstract operator [](core::String* s) → core::double*;
+  abstract operator []=(core::String* s, core::num* v) → void;
+  method test() → void {
+    core::int* v1 = let final core::String* #t209 = "x" in let final core::int* #t210 = self::getInt() in let final void #t211 = this.{self::Test8::[]=}(#t209, #t210){(core::String*, core::num*) →* void} in #t210;
+    core::num* v2 = let final core::String* #t212 = "x" in let final core::num* #t213 = self::getNum() in let final void #t214 = this.{self::Test8::[]=}(#t212, #t213){(core::String*, core::num*) →* void} in #t213;
+    core::double* v3 = let final core::String* #t215 = "x" in let final core::double* #t216 = self::getDouble() in let final void #t217 = this.{self::Test8::[]=}(#t215, #t216){(core::String*, core::num*) →* void} in #t216;
+    core::num* v4 = let final core::String* #t218 = "x" in let final core::double* #t219 = this.{self::Test8::[]}(#t218){(core::String*) →* core::double*} in #t219 == null ?{core::num*} let final core::int* #t220 = self::getInt() in let final void #t221 = this.{self::Test8::[]=}(#t218, #t220){(core::String*, core::num*) →* void} in #t220 : #t219;
+    core::num* v5 = let final core::String* #t222 = "x" in let final core::double* #t223 = this.{self::Test8::[]}(#t222){(core::String*) →* core::double*} in #t223 == null ?{core::num*} let final core::num* #t224 = self::getNum() in let final void #t225 = this.{self::Test8::[]=}(#t222, #t224){(core::String*, core::num*) →* void} in #t224 : #t223;
+    core::double* v6 = let final core::String* #t226 = "x" in let final core::double* #t227 = this.{self::Test8::[]}(#t226){(core::String*) →* core::double*} in #t227 == null ?{core::double*} let final core::double* #t228 = self::getDouble() in let final void #t229 = this.{self::Test8::[]=}(#t226, #t228){(core::String*, core::num*) →* void} in #t228 : #t227;
+    core::double* v7 = let final core::String* #t230 = "x" in let final core::double* #t231 = this.{self::Test8::[]}(#t230){(core::String*) →* core::double*}.{core::double::+}(self::getInt()){(core::num*) →* core::double*} in let final void #t232 = this.{self::Test8::[]=}(#t230, #t231){(core::String*, core::num*) →* void} in #t231;
+    core::double* v8 = let final core::String* #t233 = "x" in let final core::double* #t234 = this.{self::Test8::[]}(#t233){(core::String*) →* core::double*}.{core::double::+}(self::getNum()){(core::num*) →* core::double*} in let final void #t235 = this.{self::Test8::[]=}(#t233, #t234){(core::String*, core::num*) →* void} in #t234;
+    core::double* v9 = let final core::String* #t236 = "x" in let final core::double* #t237 = this.{self::Test8::[]}(#t236){(core::String*) →* core::double*}.{core::double::+}(self::getDouble()){(core::num*) →* core::double*} in let final void #t238 = this.{self::Test8::[]=}(#t236, #t237){(core::String*, core::num*) →* void} in #t237;
+    core::double* v10 = let final core::String* #t239 = "x" in let final core::double* #t240 = this.{self::Test8::[]}(#t239){(core::String*) →* core::double*}.{core::double::+}(1){(core::num*) →* core::double*} in let final void #t241 = this.{self::Test8::[]=}(#t239, #t240){(core::String*, core::num*) →* void} in #t240;
+    core::double* v11 = let final core::String* #t242 = "x" in let final core::double* #t243 = this.{self::Test8::[]}(#t242){(core::String*) →* core::double*} in let final void #t244 = this.{self::Test8::[]=}(#t242, #t243.{core::double::+}(1){(core::num*) →* core::double*}){(core::String*, core::num*) →* void} in #t243;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Test9 extends core::Object {
+  synthetic constructor •() → self::Test9*
+    : super core::Object::•()
+    ;
+  abstract operator [](core::String* s) → core::double*;
+  abstract operator []=(core::String* s, core::double* v) → void;
+  method test() → void {
+    core::num* v2 = let final core::String* #t245 = "x" in let final core::num* #t246 = self::getNum() as{TypeError} core::double* in let final void #t247 = this.{self::Test9::[]=}(#t245, #t246){(core::String*, core::double*) →* void} in #t246;
+    core::double* v3 = let final core::String* #t248 = "x" in let final core::double* #t249 = self::getDouble() in let final void #t250 = this.{self::Test9::[]=}(#t248, #t249){(core::String*, core::double*) →* void} in #t249;
+    core::num* v5 = let final core::String* #t251 = "x" in let final core::double* #t252 = this.{self::Test9::[]}(#t251){(core::String*) →* core::double*} in #t252 == null ?{core::num*} let final core::num* #t253 = self::getNum() as{TypeError} core::double* in let final void #t254 = this.{self::Test9::[]=}(#t251, #t253){(core::String*, core::double*) →* void} in #t253 : #t252;
+    core::double* v6 = let final core::String* #t255 = "x" in let final core::double* #t256 = this.{self::Test9::[]}(#t255){(core::String*) →* core::double*} in #t256 == null ?{core::double*} let final core::double* #t257 = self::getDouble() in let final void #t258 = this.{self::Test9::[]=}(#t255, #t257){(core::String*, core::double*) →* void} in #t257 : #t256;
+    core::double* v7 = let final core::String* #t259 = "x" in let final core::double* #t260 = this.{self::Test9::[]}(#t259){(core::String*) →* core::double*}.{core::double::+}(self::getInt()){(core::num*) →* core::double*} in let final void #t261 = this.{self::Test9::[]=}(#t259, #t260){(core::String*, core::double*) →* void} in #t260;
+    core::double* v8 = let final core::String* #t262 = "x" in let final core::double* #t263 = this.{self::Test9::[]}(#t262){(core::String*) →* core::double*}.{core::double::+}(self::getNum()){(core::num*) →* core::double*} in let final void #t264 = this.{self::Test9::[]=}(#t262, #t263){(core::String*, core::double*) →* void} in #t263;
+    core::double* v9 = let final core::String* #t265 = "x" in let final core::double* #t266 = this.{self::Test9::[]}(#t265){(core::String*) →* core::double*}.{core::double::+}(self::getDouble()){(core::num*) →* core::double*} in let final void #t267 = this.{self::Test9::[]=}(#t265, #t266){(core::String*, core::double*) →* void} in #t266;
+    core::double* v10 = let final core::String* #t268 = "x" in let final core::double* #t269 = this.{self::Test9::[]}(#t268){(core::String*) →* core::double*}.{core::double::+}(1){(core::num*) →* core::double*} in let final void #t270 = this.{self::Test9::[]=}(#t268, #t269){(core::String*, core::double*) →* void} in #t269;
+    core::double* v11 = let final core::String* #t271 = "x" in let final core::double* #t272 = this.{self::Test9::[]}(#t271){(core::String*) →* core::double*} in let final void #t273 = this.{self::Test9::[]=}(#t271, #t272.{core::double::+}(1){(core::num*) →* core::double*}){(core::String*, core::double*) →* void} in #t272;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method getInt() → core::int*
+  return 0;
+static method getNum() → core::num*
+  return 0;
+static method getDouble() → core::double*
+  return 0.0;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..895c644
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart.weak.modular.expect
@@ -0,0 +1,175 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart:90:74: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+//       t /*@target=Test.[]*/ /*@target=Test.[]=*/ ['x'] /*@target=num.+*/ +=
+//                                                                          ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart:102:25: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+//       /*@target=num.+*/ ++t /*@target=Test.[]*/ /*@target=Test.[]=*/ ['x'];
+//                         ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart:105:74: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+//       t /*@target=Test.[]*/ /*@target=Test.[]=*/ ['x'] /*@target=num.+*/ ++;
+//                                                                          ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart:211:77: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//       t /*@target=Test.[]*/ /*@target=Test.[]=*/ ['x'] /*@target=double.+*/ +=
+//                                                                             ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart:215:77: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//       t /*@target=Test.[]*/ /*@target=Test.[]=*/ ['x'] /*@target=double.+*/ +=
+//                                                                             ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart:219:28: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//       /*@target=double.+*/ ++t
+//                            ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart:223:77: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//       t /*@target=Test.[]*/ /*@target=Test.[]=*/ ['x'] /*@target=double.+*/ ++;
+//                                                                             ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Test<T extends core::Object* = dynamic, U extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Test<self::Test::T*, self::Test::U*>*
+    : super core::Object::•()
+    ;
+  abstract operator [](core::String* s) → self::Test::T*;
+  abstract operator []=(core::String* s, covariant-by-class self::Test::U* v) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method getInt() → core::int*
+  return 0;
+static method getNum() → core::num*
+  return 0;
+static method getDouble() → core::double*
+  return 0.0;
+static method test1(self::Test<core::int*, core::int*>* t) → void {
+  core::int* v1 = let final self::Test<core::int*, core::int*>* #t1 = t in let final core::String* #t2 = "x" in let final core::int* #t3 = self::getInt() in let final void #t4 = #t1.{self::Test::[]=}(#t2, #t3){(core::String*, core::int*) →* void} in #t3;
+  core::num* v2 = let final self::Test<core::int*, core::int*>* #t5 = t in let final core::String* #t6 = "x" in let final core::num* #t7 = self::getNum() as{TypeError} core::int* in let final void #t8 = #t5.{self::Test::[]=}(#t6, #t7){(core::String*, core::int*) →* void} in #t7;
+  core::int* v4 = let final self::Test<core::int*, core::int*>* #t9 = t in let final core::String* #t10 = "x" in let final core::int* #t11 = #t9.{self::Test::[]}(#t10){(core::String*) →* core::int*} in #t11 == null ?{core::int*} let final core::int* #t12 = self::getInt() in let final void #t13 = #t9.{self::Test::[]=}(#t10, #t12){(core::String*, core::int*) →* void} in #t12 : #t11;
+  core::num* v5 = let final self::Test<core::int*, core::int*>* #t14 = t in let final core::String* #t15 = "x" in let final core::int* #t16 = #t14.{self::Test::[]}(#t15){(core::String*) →* core::int*} in #t16 == null ?{core::num*} let final core::num* #t17 = self::getNum() as{TypeError} core::int* in let final void #t18 = #t14.{self::Test::[]=}(#t15, #t17){(core::String*, core::int*) →* void} in #t17 : #t16;
+  core::int* v7 = let final self::Test<core::int*, core::int*>* #t19 = t in let final core::String* #t20 = "x" in let final core::int* #t21 = #t19.{self::Test::[]}(#t20){(core::String*) →* core::int*}.{core::num::+}(self::getInt()){(core::num*) →* core::int*} in let final void #t22 = #t19.{self::Test::[]=}(#t20, #t21){(core::String*, core::int*) →* void} in #t21;
+  core::num* v8 = let final self::Test<core::int*, core::int*>* #t23 = t in let final core::String* #t24 = "x" in let final core::num* #t25 = #t23.{self::Test::[]}(#t24){(core::String*) →* core::int*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::int* in let final void #t26 = #t23.{self::Test::[]=}(#t24, #t25){(core::String*, core::int*) →* void} in #t25;
+  core::int* v10 = let final self::Test<core::int*, core::int*>* #t27 = t in let final core::String* #t28 = "x" in let final core::int* #t29 = #t27.{self::Test::[]}(#t28){(core::String*) →* core::int*}.{core::num::+}(1){(core::num*) →* core::int*} in let final void #t30 = #t27.{self::Test::[]=}(#t28, #t29){(core::String*, core::int*) →* void} in #t29;
+  core::int* v11 = let final self::Test<core::int*, core::int*>* #t31 = t in let final core::String* #t32 = "x" in let final core::int* #t33 = #t31.{self::Test::[]}(#t32){(core::String*) →* core::int*} in let final void #t34 = #t31.{self::Test::[]=}(#t32, #t33.{core::num::+}(1){(core::num*) →* core::int*}){(core::String*, core::int*) →* void} in #t33;
+}
+static method test2(self::Test<core::int*, core::num*>* t) → void {
+  core::int* v1 = let final self::Test<core::int*, core::num*>* #t35 = t in let final core::String* #t36 = "x" in let final core::int* #t37 = self::getInt() in let final void #t38 = #t35.{self::Test::[]=}(#t36, #t37){(core::String*, core::num*) →* void} in #t37;
+  core::num* v2 = let final self::Test<core::int*, core::num*>* #t39 = t in let final core::String* #t40 = "x" in let final core::num* #t41 = self::getNum() in let final void #t42 = #t39.{self::Test::[]=}(#t40, #t41){(core::String*, core::num*) →* void} in #t41;
+  core::double* v3 = let final self::Test<core::int*, core::num*>* #t43 = t in let final core::String* #t44 = "x" in let final core::double* #t45 = self::getDouble() in let final void #t46 = #t43.{self::Test::[]=}(#t44, #t45){(core::String*, core::num*) →* void} in #t45;
+  core::int* v4 = let final self::Test<core::int*, core::num*>* #t47 = t in let final core::String* #t48 = "x" in let final core::int* #t49 = #t47.{self::Test::[]}(#t48){(core::String*) →* core::int*} in #t49 == null ?{core::int*} let final core::int* #t50 = self::getInt() in let final void #t51 = #t47.{self::Test::[]=}(#t48, #t50){(core::String*, core::num*) →* void} in #t50 : #t49;
+  core::num* v5 = let final self::Test<core::int*, core::num*>* #t52 = t in let final core::String* #t53 = "x" in let final core::int* #t54 = #t52.{self::Test::[]}(#t53){(core::String*) →* core::int*} in #t54 == null ?{core::num*} let final core::num* #t55 = self::getNum() in let final void #t56 = #t52.{self::Test::[]=}(#t53, #t55){(core::String*, core::num*) →* void} in #t55 : #t54;
+  core::num* v6 = let final self::Test<core::int*, core::num*>* #t57 = t in let final core::String* #t58 = "x" in let final core::int* #t59 = #t57.{self::Test::[]}(#t58){(core::String*) →* core::int*} in #t59 == null ?{core::num*} let final core::double* #t60 = self::getDouble() in let final void #t61 = #t57.{self::Test::[]=}(#t58, #t60){(core::String*, core::num*) →* void} in #t60 : #t59;
+  core::int* v7 = let final self::Test<core::int*, core::num*>* #t62 = t in let final core::String* #t63 = "x" in let final core::int* #t64 = #t62.{self::Test::[]}(#t63){(core::String*) →* core::int*}.{core::num::+}(self::getInt()){(core::num*) →* core::int*} in let final void #t65 = #t62.{self::Test::[]=}(#t63, #t64){(core::String*, core::num*) →* void} in #t64;
+  core::num* v8 = let final self::Test<core::int*, core::num*>* #t66 = t in let final core::String* #t67 = "x" in let final core::num* #t68 = #t66.{self::Test::[]}(#t67){(core::String*) →* core::int*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} in let final void #t69 = #t66.{self::Test::[]=}(#t67, #t68){(core::String*, core::num*) →* void} in #t68;
+  core::double* v9 = let final self::Test<core::int*, core::num*>* #t70 = t in let final core::String* #t71 = "x" in let final core::double* #t72 = #t70.{self::Test::[]}(#t71){(core::String*) →* core::int*}.{core::num::+}(self::getDouble()){(core::num*) →* core::double*} in let final void #t73 = #t70.{self::Test::[]=}(#t71, #t72){(core::String*, core::num*) →* void} in #t72;
+  core::int* v10 = let final self::Test<core::int*, core::num*>* #t74 = t in let final core::String* #t75 = "x" in let final core::int* #t76 = #t74.{self::Test::[]}(#t75){(core::String*) →* core::int*}.{core::num::+}(1){(core::num*) →* core::int*} in let final void #t77 = #t74.{self::Test::[]=}(#t75, #t76){(core::String*, core::num*) →* void} in #t76;
+  core::int* v11 = let final self::Test<core::int*, core::num*>* #t78 = t in let final core::String* #t79 = "x" in let final core::int* #t80 = #t78.{self::Test::[]}(#t79){(core::String*) →* core::int*} in let final void #t81 = #t78.{self::Test::[]=}(#t79, #t80.{core::num::+}(1){(core::num*) →* core::int*}){(core::String*, core::num*) →* void} in #t80;
+}
+static method test3(self::Test<core::int*, core::double*>* t) → void {
+  core::num* v2 = let final self::Test<core::int*, core::double*>* #t82 = t in let final core::String* #t83 = "x" in let final core::num* #t84 = self::getNum() as{TypeError} core::double* in let final void #t85 = #t82.{self::Test::[]=}(#t83, #t84){(core::String*, core::double*) →* void} in #t84;
+  core::double* v3 = let final self::Test<core::int*, core::double*>* #t86 = t in let final core::String* #t87 = "x" in let final core::double* #t88 = self::getDouble() in let final void #t89 = #t86.{self::Test::[]=}(#t87, #t88){(core::String*, core::double*) →* void} in #t88;
+  core::num* v5 = let final self::Test<core::int*, core::double*>* #t90 = t in let final core::String* #t91 = "x" in let final core::int* #t92 = #t90.{self::Test::[]}(#t91){(core::String*) →* core::int*} in #t92 == null ?{core::num*} let final core::num* #t93 = self::getNum() as{TypeError} core::double* in let final void #t94 = #t90.{self::Test::[]=}(#t91, #t93){(core::String*, core::double*) →* void} in #t93 : #t92;
+  core::num* v6 = let final self::Test<core::int*, core::double*>* #t95 = t in let final core::String* #t96 = "x" in let final core::int* #t97 = #t95.{self::Test::[]}(#t96){(core::String*) →* core::int*} in #t97 == null ?{core::num*} let final core::double* #t98 = self::getDouble() in let final void #t99 = #t95.{self::Test::[]=}(#t96, #t98){(core::String*, core::double*) →* void} in #t98 : #t97;
+  core::int* v7 = let final self::Test<core::int*, core::double*>* #t100 = t in let final core::String* #t101 = "x" in let final core::int* #t102 = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart:90:74: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+      t /*@target=Test.[]*/ /*@target=Test.[]=*/ ['x'] /*@target=num.+*/ +=
+                                                                         ^" in #t100.{self::Test::[]}(#t101){(core::String*) →* core::int*}.{core::num::+}(self::getInt()){(core::num*) →* core::int*} as{TypeError} core::double* in let final void #t103 = #t100.{self::Test::[]=}(#t101, #t102){(core::String*, core::double*) →* void} in #t102;
+  core::num* v8 = let final self::Test<core::int*, core::double*>* #t104 = t in let final core::String* #t105 = "x" in let final core::num* #t106 = #t104.{self::Test::[]}(#t105){(core::String*) →* core::int*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::double* in let final void #t107 = #t104.{self::Test::[]=}(#t105, #t106){(core::String*, core::double*) →* void} in #t106;
+  core::double* v9 = let final self::Test<core::int*, core::double*>* #t108 = t in let final core::String* #t109 = "x" in let final core::double* #t110 = #t108.{self::Test::[]}(#t109){(core::String*) →* core::int*}.{core::num::+}(self::getDouble()){(core::num*) →* core::double*} in let final void #t111 = #t108.{self::Test::[]=}(#t109, #t110){(core::String*, core::double*) →* void} in #t110;
+  core::int* v10 = let final self::Test<core::int*, core::double*>* #t112 = t in let final core::String* #t113 = "x" in let final core::int* #t114 = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart:102:25: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+      /*@target=num.+*/ ++t /*@target=Test.[]*/ /*@target=Test.[]=*/ ['x'];
+                        ^" in #t112.{self::Test::[]}(#t113){(core::String*) →* core::int*}.{core::num::+}(1){(core::num*) →* core::int*} as{TypeError} core::double* in let final void #t115 = #t112.{self::Test::[]=}(#t113, #t114){(core::String*, core::double*) →* void} in #t114;
+  core::int* v11 = let final self::Test<core::int*, core::double*>* #t116 = t in let final core::String* #t117 = "x" in let final core::int* #t118 = #t116.{self::Test::[]}(#t117){(core::String*) →* core::int*} in let final void #t119 = #t116.{self::Test::[]=}(#t117, invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart:105:74: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+      t /*@target=Test.[]*/ /*@target=Test.[]=*/ ['x'] /*@target=num.+*/ ++;
+                                                                         ^" in #t118.{core::num::+}(1){(core::num*) →* core::int*} as{TypeError} core::double*){(core::String*, core::double*) →* void} in #t118;
+}
+static method test4(self::Test<core::num*, core::int*>* t) → void {
+  core::int* v1 = let final self::Test<core::num*, core::int*>* #t120 = t in let final core::String* #t121 = "x" in let final core::int* #t122 = self::getInt() in let final void #t123 = #t120.{self::Test::[]=}(#t121, #t122){(core::String*, core::int*) →* void} in #t122;
+  core::num* v2 = let final self::Test<core::num*, core::int*>* #t124 = t in let final core::String* #t125 = "x" in let final core::num* #t126 = self::getNum() as{TypeError} core::int* in let final void #t127 = #t124.{self::Test::[]=}(#t125, #t126){(core::String*, core::int*) →* void} in #t126;
+  core::num* v4 = let final self::Test<core::num*, core::int*>* #t128 = t in let final core::String* #t129 = "x" in let final core::num* #t130 = #t128.{self::Test::[]}(#t129){(core::String*) →* core::num*} in #t130 == null ?{core::num*} let final core::int* #t131 = self::getInt() in let final void #t132 = #t128.{self::Test::[]=}(#t129, #t131){(core::String*, core::int*) →* void} in #t131 : #t130;
+  core::num* v5 = let final self::Test<core::num*, core::int*>* #t133 = t in let final core::String* #t134 = "x" in let final core::num* #t135 = #t133.{self::Test::[]}(#t134){(core::String*) →* core::num*} in #t135 == null ?{core::num*} let final core::num* #t136 = self::getNum() as{TypeError} core::int* in let final void #t137 = #t133.{self::Test::[]=}(#t134, #t136){(core::String*, core::int*) →* void} in #t136 : #t135;
+  core::num* v7 = let final self::Test<core::num*, core::int*>* #t138 = t in let final core::String* #t139 = "x" in let final core::num* #t140 = #t138.{self::Test::[]}(#t139){(core::String*) →* core::num*}.{core::num::+}(self::getInt()){(core::num*) →* core::num*} as{TypeError} core::int* in let final void #t141 = #t138.{self::Test::[]=}(#t139, #t140){(core::String*, core::int*) →* void} in #t140;
+  core::num* v8 = let final self::Test<core::num*, core::int*>* #t142 = t in let final core::String* #t143 = "x" in let final core::num* #t144 = #t142.{self::Test::[]}(#t143){(core::String*) →* core::num*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::int* in let final void #t145 = #t142.{self::Test::[]=}(#t143, #t144){(core::String*, core::int*) →* void} in #t144;
+  core::num* v10 = let final self::Test<core::num*, core::int*>* #t146 = t in let final core::String* #t147 = "x" in let final core::num* #t148 = #t146.{self::Test::[]}(#t147){(core::String*) →* core::num*}.{core::num::+}(1){(core::num*) →* core::num*} as{TypeError} core::int* in let final void #t149 = #t146.{self::Test::[]=}(#t147, #t148){(core::String*, core::int*) →* void} in #t148;
+  core::num* v11 = let final self::Test<core::num*, core::int*>* #t150 = t in let final core::String* #t151 = "x" in let final core::num* #t152 = #t150.{self::Test::[]}(#t151){(core::String*) →* core::num*} in let final void #t153 = #t150.{self::Test::[]=}(#t151, #t152.{core::num::+}(1){(core::num*) →* core::num*} as{TypeError} core::int*){(core::String*, core::int*) →* void} in #t152;
+}
+static method test5(self::Test<core::num*, core::num*>* t) → void {
+  core::int* v1 = let final self::Test<core::num*, core::num*>* #t154 = t in let final core::String* #t155 = "x" in let final core::int* #t156 = self::getInt() in let final void #t157 = #t154.{self::Test::[]=}(#t155, #t156){(core::String*, core::num*) →* void} in #t156;
+  core::num* v2 = let final self::Test<core::num*, core::num*>* #t158 = t in let final core::String* #t159 = "x" in let final core::num* #t160 = self::getNum() in let final void #t161 = #t158.{self::Test::[]=}(#t159, #t160){(core::String*, core::num*) →* void} in #t160;
+  core::double* v3 = let final self::Test<core::num*, core::num*>* #t162 = t in let final core::String* #t163 = "x" in let final core::double* #t164 = self::getDouble() in let final void #t165 = #t162.{self::Test::[]=}(#t163, #t164){(core::String*, core::num*) →* void} in #t164;
+  core::num* v4 = let final self::Test<core::num*, core::num*>* #t166 = t in let final core::String* #t167 = "x" in let final core::num* #t168 = #t166.{self::Test::[]}(#t167){(core::String*) →* core::num*} in #t168 == null ?{core::num*} let final core::int* #t169 = self::getInt() in let final void #t170 = #t166.{self::Test::[]=}(#t167, #t169){(core::String*, core::num*) →* void} in #t169 : #t168;
+  core::num* v5 = let final self::Test<core::num*, core::num*>* #t171 = t in let final core::String* #t172 = "x" in let final core::num* #t173 = #t171.{self::Test::[]}(#t172){(core::String*) →* core::num*} in #t173 == null ?{core::num*} let final core::num* #t174 = self::getNum() in let final void #t175 = #t171.{self::Test::[]=}(#t172, #t174){(core::String*, core::num*) →* void} in #t174 : #t173;
+  core::num* v6 = let final self::Test<core::num*, core::num*>* #t176 = t in let final core::String* #t177 = "x" in let final core::num* #t178 = #t176.{self::Test::[]}(#t177){(core::String*) →* core::num*} in #t178 == null ?{core::num*} let final core::double* #t179 = self::getDouble() in let final void #t180 = #t176.{self::Test::[]=}(#t177, #t179){(core::String*, core::num*) →* void} in #t179 : #t178;
+  core::num* v7 = let final self::Test<core::num*, core::num*>* #t181 = t in let final core::String* #t182 = "x" in let final core::num* #t183 = #t181.{self::Test::[]}(#t182){(core::String*) →* core::num*}.{core::num::+}(self::getInt()){(core::num*) →* core::num*} in let final void #t184 = #t181.{self::Test::[]=}(#t182, #t183){(core::String*, core::num*) →* void} in #t183;
+  core::num* v8 = let final self::Test<core::num*, core::num*>* #t185 = t in let final core::String* #t186 = "x" in let final core::num* #t187 = #t185.{self::Test::[]}(#t186){(core::String*) →* core::num*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} in let final void #t188 = #t185.{self::Test::[]=}(#t186, #t187){(core::String*, core::num*) →* void} in #t187;
+  core::num* v9 = let final self::Test<core::num*, core::num*>* #t189 = t in let final core::String* #t190 = "x" in let final core::num* #t191 = #t189.{self::Test::[]}(#t190){(core::String*) →* core::num*}.{core::num::+}(self::getDouble()){(core::num*) →* core::num*} in let final void #t192 = #t189.{self::Test::[]=}(#t190, #t191){(core::String*, core::num*) →* void} in #t191;
+  core::num* v10 = let final self::Test<core::num*, core::num*>* #t193 = t in let final core::String* #t194 = "x" in let final core::num* #t195 = #t193.{self::Test::[]}(#t194){(core::String*) →* core::num*}.{core::num::+}(1){(core::num*) →* core::num*} in let final void #t196 = #t193.{self::Test::[]=}(#t194, #t195){(core::String*, core::num*) →* void} in #t195;
+  core::num* v11 = let final self::Test<core::num*, core::num*>* #t197 = t in let final core::String* #t198 = "x" in let final core::num* #t199 = #t197.{self::Test::[]}(#t198){(core::String*) →* core::num*} in let final void #t200 = #t197.{self::Test::[]=}(#t198, #t199.{core::num::+}(1){(core::num*) →* core::num*}){(core::String*, core::num*) →* void} in #t199;
+}
+static method test6(self::Test<core::num*, core::double*>* t) → void {
+  core::num* v2 = let final self::Test<core::num*, core::double*>* #t201 = t in let final core::String* #t202 = "x" in let final core::num* #t203 = self::getNum() as{TypeError} core::double* in let final void #t204 = #t201.{self::Test::[]=}(#t202, #t203){(core::String*, core::double*) →* void} in #t203;
+  core::double* v3 = let final self::Test<core::num*, core::double*>* #t205 = t in let final core::String* #t206 = "x" in let final core::double* #t207 = self::getDouble() in let final void #t208 = #t205.{self::Test::[]=}(#t206, #t207){(core::String*, core::double*) →* void} in #t207;
+  core::num* v5 = let final self::Test<core::num*, core::double*>* #t209 = t in let final core::String* #t210 = "x" in let final core::num* #t211 = #t209.{self::Test::[]}(#t210){(core::String*) →* core::num*} in #t211 == null ?{core::num*} let final core::num* #t212 = self::getNum() as{TypeError} core::double* in let final void #t213 = #t209.{self::Test::[]=}(#t210, #t212){(core::String*, core::double*) →* void} in #t212 : #t211;
+  core::num* v6 = let final self::Test<core::num*, core::double*>* #t214 = t in let final core::String* #t215 = "x" in let final core::num* #t216 = #t214.{self::Test::[]}(#t215){(core::String*) →* core::num*} in #t216 == null ?{core::num*} let final core::double* #t217 = self::getDouble() in let final void #t218 = #t214.{self::Test::[]=}(#t215, #t217){(core::String*, core::double*) →* void} in #t217 : #t216;
+  core::num* v7 = let final self::Test<core::num*, core::double*>* #t219 = t in let final core::String* #t220 = "x" in let final core::num* #t221 = #t219.{self::Test::[]}(#t220){(core::String*) →* core::num*}.{core::num::+}(self::getInt()){(core::num*) →* core::num*} as{TypeError} core::double* in let final void #t222 = #t219.{self::Test::[]=}(#t220, #t221){(core::String*, core::double*) →* void} in #t221;
+  core::num* v8 = let final self::Test<core::num*, core::double*>* #t223 = t in let final core::String* #t224 = "x" in let final core::num* #t225 = #t223.{self::Test::[]}(#t224){(core::String*) →* core::num*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::double* in let final void #t226 = #t223.{self::Test::[]=}(#t224, #t225){(core::String*, core::double*) →* void} in #t225;
+  core::num* v9 = let final self::Test<core::num*, core::double*>* #t227 = t in let final core::String* #t228 = "x" in let final core::num* #t229 = #t227.{self::Test::[]}(#t228){(core::String*) →* core::num*}.{core::num::+}(self::getDouble()){(core::num*) →* core::num*} as{TypeError} core::double* in let final void #t230 = #t227.{self::Test::[]=}(#t228, #t229){(core::String*, core::double*) →* void} in #t229;
+  core::num* v10 = let final self::Test<core::num*, core::double*>* #t231 = t in let final core::String* #t232 = "x" in let final core::num* #t233 = #t231.{self::Test::[]}(#t232){(core::String*) →* core::num*}.{core::num::+}(1){(core::num*) →* core::num*} as{TypeError} core::double* in let final void #t234 = #t231.{self::Test::[]=}(#t232, #t233){(core::String*, core::double*) →* void} in #t233;
+  core::num* v11 = let final self::Test<core::num*, core::double*>* #t235 = t in let final core::String* #t236 = "x" in let final core::num* #t237 = #t235.{self::Test::[]}(#t236){(core::String*) →* core::num*} in let final void #t238 = #t235.{self::Test::[]=}(#t236, #t237.{core::num::+}(1){(core::num*) →* core::num*} as{TypeError} core::double*){(core::String*, core::double*) →* void} in #t237;
+}
+static method test7(self::Test<core::double*, core::int*>* t) → void {
+  core::int* v1 = let final self::Test<core::double*, core::int*>* #t239 = t in let final core::String* #t240 = "x" in let final core::int* #t241 = self::getInt() in let final void #t242 = #t239.{self::Test::[]=}(#t240, #t241){(core::String*, core::int*) →* void} in #t241;
+  core::num* v2 = let final self::Test<core::double*, core::int*>* #t243 = t in let final core::String* #t244 = "x" in let final core::num* #t245 = self::getNum() as{TypeError} core::int* in let final void #t246 = #t243.{self::Test::[]=}(#t244, #t245){(core::String*, core::int*) →* void} in #t245;
+  core::num* v4 = let final self::Test<core::double*, core::int*>* #t247 = t in let final core::String* #t248 = "x" in let final core::double* #t249 = #t247.{self::Test::[]}(#t248){(core::String*) →* core::double*} in #t249 == null ?{core::num*} let final core::int* #t250 = self::getInt() in let final void #t251 = #t247.{self::Test::[]=}(#t248, #t250){(core::String*, core::int*) →* void} in #t250 : #t249;
+  core::num* v5 = let final self::Test<core::double*, core::int*>* #t252 = t in let final core::String* #t253 = "x" in let final core::double* #t254 = #t252.{self::Test::[]}(#t253){(core::String*) →* core::double*} in #t254 == null ?{core::num*} let final core::num* #t255 = self::getNum() as{TypeError} core::int* in let final void #t256 = #t252.{self::Test::[]=}(#t253, #t255){(core::String*, core::int*) →* void} in #t255 : #t254;
+  core::double* v7 = let final self::Test<core::double*, core::int*>* #t257 = t in let final core::String* #t258 = "x" in let final core::double* #t259 = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart:211:77: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+      t /*@target=Test.[]*/ /*@target=Test.[]=*/ ['x'] /*@target=double.+*/ +=
+                                                                            ^" in #t257.{self::Test::[]}(#t258){(core::String*) →* core::double*}.{core::double::+}(self::getInt()){(core::num*) →* core::double*} as{TypeError} core::int* in let final void #t260 = #t257.{self::Test::[]=}(#t258, #t259){(core::String*, core::int*) →* void} in #t259;
+  core::double* v8 = let final self::Test<core::double*, core::int*>* #t261 = t in let final core::String* #t262 = "x" in let final core::double* #t263 = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart:215:77: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+      t /*@target=Test.[]*/ /*@target=Test.[]=*/ ['x'] /*@target=double.+*/ +=
+                                                                            ^" in #t261.{self::Test::[]}(#t262){(core::String*) →* core::double*}.{core::double::+}(self::getNum()){(core::num*) →* core::double*} as{TypeError} core::int* in let final void #t264 = #t261.{self::Test::[]=}(#t262, #t263){(core::String*, core::int*) →* void} in #t263;
+  core::double* v10 = let final self::Test<core::double*, core::int*>* #t265 = t in let final core::String* #t266 = "x" in let final core::double* #t267 = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart:219:28: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+      /*@target=double.+*/ ++t
+                           ^" in #t265.{self::Test::[]}(#t266){(core::String*) →* core::double*}.{core::double::+}(1){(core::num*) →* core::double*} as{TypeError} core::int* in let final void #t268 = #t265.{self::Test::[]=}(#t266, #t267){(core::String*, core::int*) →* void} in #t267;
+  core::double* v11 = let final self::Test<core::double*, core::int*>* #t269 = t in let final core::String* #t270 = "x" in let final core::double* #t271 = #t269.{self::Test::[]}(#t270){(core::String*) →* core::double*} in let final void #t272 = #t269.{self::Test::[]=}(#t270, invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_index_upwards.dart:223:77: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+      t /*@target=Test.[]*/ /*@target=Test.[]=*/ ['x'] /*@target=double.+*/ ++;
+                                                                            ^" in #t271.{core::double::+}(1){(core::num*) →* core::double*} as{TypeError} core::int*){(core::String*, core::int*) →* void} in #t271;
+}
+static method test8(self::Test<core::double*, core::num*>* t) → void {
+  core::int* v1 = let final self::Test<core::double*, core::num*>* #t273 = t in let final core::String* #t274 = "x" in let final core::int* #t275 = self::getInt() in let final void #t276 = #t273.{self::Test::[]=}(#t274, #t275){(core::String*, core::num*) →* void} in #t275;
+  core::num* v2 = let final self::Test<core::double*, core::num*>* #t277 = t in let final core::String* #t278 = "x" in let final core::num* #t279 = self::getNum() in let final void #t280 = #t277.{self::Test::[]=}(#t278, #t279){(core::String*, core::num*) →* void} in #t279;
+  core::double* v3 = let final self::Test<core::double*, core::num*>* #t281 = t in let final core::String* #t282 = "x" in let final core::double* #t283 = self::getDouble() in let final void #t284 = #t281.{self::Test::[]=}(#t282, #t283){(core::String*, core::num*) →* void} in #t283;
+  core::num* v4 = let final self::Test<core::double*, core::num*>* #t285 = t in let final core::String* #t286 = "x" in let final core::double* #t287 = #t285.{self::Test::[]}(#t286){(core::String*) →* core::double*} in #t287 == null ?{core::num*} let final core::int* #t288 = self::getInt() in let final void #t289 = #t285.{self::Test::[]=}(#t286, #t288){(core::String*, core::num*) →* void} in #t288 : #t287;
+  core::num* v5 = let final self::Test<core::double*, core::num*>* #t290 = t in let final core::String* #t291 = "x" in let final core::double* #t292 = #t290.{self::Test::[]}(#t291){(core::String*) →* core::double*} in #t292 == null ?{core::num*} let final core::num* #t293 = self::getNum() in let final void #t294 = #t290.{self::Test::[]=}(#t291, #t293){(core::String*, core::num*) →* void} in #t293 : #t292;
+  core::double* v6 = let final self::Test<core::double*, core::num*>* #t295 = t in let final core::String* #t296 = "x" in let final core::double* #t297 = #t295.{self::Test::[]}(#t296){(core::String*) →* core::double*} in #t297 == null ?{core::double*} let final core::double* #t298 = self::getDouble() in let final void #t299 = #t295.{self::Test::[]=}(#t296, #t298){(core::String*, core::num*) →* void} in #t298 : #t297;
+  core::double* v7 = let final self::Test<core::double*, core::num*>* #t300 = t in let final core::String* #t301 = "x" in let final core::double* #t302 = #t300.{self::Test::[]}(#t301){(core::String*) →* core::double*}.{core::double::+}(self::getInt()){(core::num*) →* core::double*} in let final void #t303 = #t300.{self::Test::[]=}(#t301, #t302){(core::String*, core::num*) →* void} in #t302;
+  core::double* v8 = let final self::Test<core::double*, core::num*>* #t304 = t in let final core::String* #t305 = "x" in let final core::double* #t306 = #t304.{self::Test::[]}(#t305){(core::String*) →* core::double*}.{core::double::+}(self::getNum()){(core::num*) →* core::double*} in let final void #t307 = #t304.{self::Test::[]=}(#t305, #t306){(core::String*, core::num*) →* void} in #t306;
+  core::double* v9 = let final self::Test<core::double*, core::num*>* #t308 = t in let final core::String* #t309 = "x" in let final core::double* #t310 = #t308.{self::Test::[]}(#t309){(core::String*) →* core::double*}.{core::double::+}(self::getDouble()){(core::num*) →* core::double*} in let final void #t311 = #t308.{self::Test::[]=}(#t309, #t310){(core::String*, core::num*) →* void} in #t310;
+  core::double* v10 = let final self::Test<core::double*, core::num*>* #t312 = t in let final core::String* #t313 = "x" in let final core::double* #t314 = #t312.{self::Test::[]}(#t313){(core::String*) →* core::double*}.{core::double::+}(1){(core::num*) →* core::double*} in let final void #t315 = #t312.{self::Test::[]=}(#t313, #t314){(core::String*, core::num*) →* void} in #t314;
+  core::double* v11 = let final self::Test<core::double*, core::num*>* #t316 = t in let final core::String* #t317 = "x" in let final core::double* #t318 = #t316.{self::Test::[]}(#t317){(core::String*) →* core::double*} in let final void #t319 = #t316.{self::Test::[]=}(#t317, #t318.{core::double::+}(1){(core::num*) →* core::double*}){(core::String*, core::num*) →* void} in #t318;
+}
+static method test9(self::Test<core::double*, core::double*>* t) → void {
+  core::num* v2 = let final self::Test<core::double*, core::double*>* #t320 = t in let final core::String* #t321 = "x" in let final core::num* #t322 = self::getNum() as{TypeError} core::double* in let final void #t323 = #t320.{self::Test::[]=}(#t321, #t322){(core::String*, core::double*) →* void} in #t322;
+  core::double* v3 = let final self::Test<core::double*, core::double*>* #t324 = t in let final core::String* #t325 = "x" in let final core::double* #t326 = self::getDouble() in let final void #t327 = #t324.{self::Test::[]=}(#t325, #t326){(core::String*, core::double*) →* void} in #t326;
+  core::num* v5 = let final self::Test<core::double*, core::double*>* #t328 = t in let final core::String* #t329 = "x" in let final core::double* #t330 = #t328.{self::Test::[]}(#t329){(core::String*) →* core::double*} in #t330 == null ?{core::num*} let final core::num* #t331 = self::getNum() as{TypeError} core::double* in let final void #t332 = #t328.{self::Test::[]=}(#t329, #t331){(core::String*, core::double*) →* void} in #t331 : #t330;
+  core::double* v6 = let final self::Test<core::double*, core::double*>* #t333 = t in let final core::String* #t334 = "x" in let final core::double* #t335 = #t333.{self::Test::[]}(#t334){(core::String*) →* core::double*} in #t335 == null ?{core::double*} let final core::double* #t336 = self::getDouble() in let final void #t337 = #t333.{self::Test::[]=}(#t334, #t336){(core::String*, core::double*) →* void} in #t336 : #t335;
+  core::double* v7 = let final self::Test<core::double*, core::double*>* #t338 = t in let final core::String* #t339 = "x" in let final core::double* #t340 = #t338.{self::Test::[]}(#t339){(core::String*) →* core::double*}.{core::double::+}(self::getInt()){(core::num*) →* core::double*} in let final void #t341 = #t338.{self::Test::[]=}(#t339, #t340){(core::String*, core::double*) →* void} in #t340;
+  core::double* v8 = let final self::Test<core::double*, core::double*>* #t342 = t in let final core::String* #t343 = "x" in let final core::double* #t344 = #t342.{self::Test::[]}(#t343){(core::String*) →* core::double*}.{core::double::+}(self::getNum()){(core::num*) →* core::double*} in let final void #t345 = #t342.{self::Test::[]=}(#t343, #t344){(core::String*, core::double*) →* void} in #t344;
+  core::double* v9 = let final self::Test<core::double*, core::double*>* #t346 = t in let final core::String* #t347 = "x" in let final core::double* #t348 = #t346.{self::Test::[]}(#t347){(core::String*) →* core::double*}.{core::double::+}(self::getDouble()){(core::num*) →* core::double*} in let final void #t349 = #t346.{self::Test::[]=}(#t347, #t348){(core::String*, core::double*) →* void} in #t348;
+  core::double* v10 = let final self::Test<core::double*, core::double*>* #t350 = t in let final core::String* #t351 = "x" in let final core::double* #t352 = #t350.{self::Test::[]}(#t351){(core::String*) →* core::double*}.{core::double::+}(1){(core::num*) →* core::double*} in let final void #t353 = #t350.{self::Test::[]=}(#t351, #t352){(core::String*, core::double*) →* void} in #t352;
+  core::double* v11 = let final self::Test<core::double*, core::double*>* #t354 = t in let final core::String* #t355 = "x" in let final core::double* #t356 = #t354.{self::Test::[]}(#t355){(core::String*) →* core::double*} in let final void #t357 = #t354.{self::Test::[]=}(#t355, #t356.{core::double::+}(1){(core::num*) →* core::double*}){(core::String*, core::double*) →* void} in #t356;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_local.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_local.dart.weak.modular.expect
new file mode 100644
index 0000000..5bdc052
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_local.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method test() → void {
+  self::B* local;
+  local = self::f<self::B*>();
+  local == null ?{self::B*} local = self::f<self::B*>() : null;
+  local = local.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+  local = local.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+  local = local.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+  local = local.{self::B::-}(1){(core::int*) →* self::B*};
+  local = local.{self::B::-}(1){(core::int*) →* self::B*};
+  self::B* v1 = local = self::f<self::B*>();
+  self::B* v2 = let final self::B* #t1 = local in #t1 == null ?{self::B*} local = self::f<self::B*>() : #t1;
+  self::A* v3 = local = local.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+  self::B* v4 = local = local.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+  self::C* v5 = local = local.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+  self::B* v6 = local = local.{self::B::-}(1){(core::int*) →* self::B*};
+  self::B* v7 = let final self::B* #t2 = local in let final self::B* #t3 = local = #t2.{self::B::-}(1){(core::int*) →* self::B*} in #t2;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_local_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_local_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..9e55829
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_local_upwards.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method getInt() → core::int*
+  return 0;
+static method getNum() → core::num*
+  return 0;
+static method getDouble() → core::double*
+  return 0.0;
+static method test1(core::int* t) → void {
+  core::int* v1 = t = self::getInt();
+  core::num* v2 = t = self::getNum() as{TypeError} core::int*;
+  core::int* v4 = let final core::int* #t1 = t in #t1 == null ?{core::int*} t = self::getInt() : #t1;
+  core::num* v5 = let final core::int* #t2 = t in #t2 == null ?{core::num*} t = self::getNum() as{TypeError} core::int* : #t2;
+  core::int* v7 = t = t.{core::num::+}(self::getInt()){(core::num*) →* core::int*};
+  core::num* v8 = t = t.{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::int*;
+  core::int* v10 = t = t.{core::num::+}(1){(core::num*) →* core::int*};
+  core::int* v11 = let final core::int* #t3 = t in let final core::int* #t4 = t = #t3.{core::num::+}(1){(core::num*) →* core::int*} in #t3;
+}
+static method test2(core::num* t) → void {
+  core::int* v1 = t = self::getInt();
+  core::num* v2 = t = self::getNum();
+  core::double* v3 = t = self::getDouble();
+  core::num* v4 = let final core::num* #t5 = t in #t5 == null ?{core::num*} t = self::getInt() : #t5;
+  core::num* v5 = let final core::num* #t6 = t in #t6 == null ?{core::num*} t = self::getNum() : #t6;
+  core::num* v6 = let final core::num* #t7 = t in #t7 == null ?{core::num*} t = self::getDouble() : #t7;
+  core::num* v7 = t = t.{core::num::+}(self::getInt()){(core::num*) →* core::num*};
+  core::num* v8 = t = t.{core::num::+}(self::getNum()){(core::num*) →* core::num*};
+  core::num* v9 = t = t.{core::num::+}(self::getDouble()){(core::num*) →* core::num*};
+  core::num* v10 = t = t.{core::num::+}(1){(core::num*) →* core::num*};
+  core::num* v11 = let final core::num* #t8 = t in let final core::num* #t9 = t = #t8.{core::num::+}(1){(core::num*) →* core::num*} in #t8;
+}
+static method test3(core::double* t) → void {
+  core::num* v2 = t = self::getNum() as{TypeError} core::double*;
+  core::double* v3 = t = self::getDouble();
+  core::num* v5 = let final core::double* #t10 = t in #t10 == null ?{core::num*} t = self::getNum() as{TypeError} core::double* : #t10;
+  core::double* v6 = let final core::double* #t11 = t in #t11 == null ?{core::double*} t = self::getDouble() : #t11;
+  core::double* v7 = t = t.{core::double::+}(self::getInt()){(core::num*) →* core::double*};
+  core::double* v8 = t = t.{core::double::+}(self::getNum()){(core::num*) →* core::double*};
+  core::double* v9 = t = t.{core::double::+}(self::getDouble()){(core::num*) →* core::double*};
+  core::double* v10 = t = t.{core::double::+}(1){(core::num*) →* core::double*};
+  core::double* v11 = let final core::double* #t12 = t in let final core::double* #t13 = t = #t12.{core::double::+}(1){(core::num*) →* core::double*} in #t12;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_property.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_property.dart.weak.modular.expect
new file mode 100644
index 0000000..6ae0089
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_property.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* f = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* v_assign = new self::A::•().{self::A::f} = 1;
+static field core::int* v_plus = let final self::A* #t1 = new self::A::•() in #t1.{self::A::f} = #t1.{self::A::f}{core::int*}.{core::num::+}(1){(core::num*) →* core::int*};
+static field core::int* v_minus = let final self::A* #t2 = new self::A::•() in #t2.{self::A::f} = #t2.{self::A::f}{core::int*}.{core::num::-}(1){(core::num*) →* core::int*};
+static field core::int* v_multiply = let final self::A* #t3 = new self::A::•() in #t3.{self::A::f} = #t3.{self::A::f}{core::int*}.{core::num::*}(1){(core::num*) →* core::int*};
+static field core::int* v_prefix_pp = let final self::A* #t4 = new self::A::•() in #t4.{self::A::f} = #t4.{self::A::f}{core::int*}.{core::num::+}(1){(core::num*) →* core::int*};
+static field core::int* v_prefix_mm = let final self::A* #t5 = new self::A::•() in #t5.{self::A::f} = #t5.{self::A::f}{core::int*}.{core::num::-}(1){(core::num*) →* core::int*};
+static field core::int* v_postfix_pp = let final self::A* #t6 = new self::A::•() in let final core::int* #t7 = #t6.{self::A::f}{core::int*} in let final core::int* #t8 = #t6.{self::A::f} = #t7.{core::num::+}(1){(core::num*) →* core::int*} in #t7;
+static field core::int* v_postfix_mm = let final self::A* #t9 = new self::A::•() in let final core::int* #t10 = #t9.{self::A::f}{core::int*} in let final core::int* #t11 = #t9.{self::A::f} = #t10.{core::num::-}(1){(core::num*) →* core::int*} in #t10;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart.weak.modular.expect
new file mode 100644
index 0000000..1bf4996
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart.weak.modular.expect
@@ -0,0 +1,79 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart:17:36: Error: A value of type 'int' can't be assigned to a variable of type 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart'.
+// var v_prefix_pp = (/*@target=A.+*/ ++new /*@ type=B* */ B()
+//                                    ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart:19:36: Error: A value of type 'double' can't be assigned to a variable of type 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart'.
+// var v_prefix_mm = (/*@target=A.-*/ --new /*@ type=B* */ B()
+//                                    ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart:23:40: Error: A value of type 'int' can't be assigned to a variable of type 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart'.
+//     /*@ type=int* */ a /*@target=A.+*/ ++);
+//                                        ^
+//
+// pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart:26:43: Error: A value of type 'double' can't be assigned to a variable of type 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart'.
+//     /*@ type=double* */ a /*@target=A.-*/ --);
+//                                           ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator +(dynamic other) → core::int*
+    return 1;
+  operator -(dynamic other) → core::double*
+    return 2.0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  field self::A* a = null;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::int* v_prefix_pp = let final self::B* #t1 = new self::B::•() in #t1.{self::B::a} = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart:17:36: Error: A value of type 'int' can't be assigned to a variable of type 'A'.
+ - 'A' is from 'pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart'.
+var v_prefix_pp = (/*@target=A.+*/ ++new /*@ type=B* */ B()
+                                   ^" in #t1.{self::B::a}{self::A*}.{self::A::+}(1){(dynamic) →* core::int*} as{TypeError} self::A*;
+static field core::double* v_prefix_mm = let final self::B* #t2 = new self::B::•() in #t2.{self::B::a} = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart:19:36: Error: A value of type 'double' can't be assigned to a variable of type 'A'.
+ - 'A' is from 'pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart'.
+var v_prefix_mm = (/*@target=A.-*/ --new /*@ type=B* */ B()
+                                   ^" in #t2.{self::B::a}{self::A*}.{self::A::-}(1){(dynamic) →* core::double*} as{TypeError} self::A*;
+static field self::A* v_postfix_pp = let final self::B* #t3 = new self::B::•() in let final self::A* #t4 = #t3.{self::B::a}{self::A*} in let final core::int* #t5 = #t3.{self::B::a} = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart:23:40: Error: A value of type 'int' can't be assigned to a variable of type 'A'.
+ - 'A' is from 'pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart'.
+    /*@ type=int* */ a /*@target=A.+*/ ++);
+                                       ^" in #t4.{self::A::+}(1){(dynamic) →* core::int*} as{TypeError} self::A* in #t4;
+static field self::A* v_postfix_mm = let final self::B* #t6 = new self::B::•() in let final self::A* #t7 = #t6.{self::B::a}{self::A*} in let final core::double* #t8 = #t6.{self::B::a} = invalid-expression "pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart:26:43: Error: A value of type 'double' can't be assigned to a variable of type 'A'.
+ - 'A' is from 'pkg/front_end/testcases/inference_new/infer_assign_to_property_custom.dart'.
+    /*@ type=double* */ a /*@target=A.-*/ --);
+                                          ^" in #t7.{self::A::-}(1){(dynamic) →* core::double*} as{TypeError} self::A* in #t7;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_property_full.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_property_full.dart.weak.modular.expect
new file mode 100644
index 0000000..2e41284
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_property_full.dart.weak.modular.expect
@@ -0,0 +1,72 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class Test extends core::Object {
+  field self::B* member = null;
+  synthetic constructor •() → self::Test*
+    : super core::Object::•()
+    ;
+  static method test(self::Test* t) → void {
+    t.{self::Test::member} = self::f<self::B*>();
+    let final self::Test* #t1 = t in #t1.{self::Test::member}{self::B*} == null ?{self::B*} #t1.{self::Test::member} = self::f<self::B*>() : null;
+    let final self::Test* #t2 = t in #t2.{self::Test::member} = #t2.{self::Test::member}{self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+    let final self::Test* #t3 = t in #t3.{self::Test::member} = #t3.{self::Test::member}{self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+    let final self::Test* #t4 = t in #t4.{self::Test::member} = #t4.{self::Test::member}{self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+    let final self::Test* #t5 = t in #t5.{self::Test::member} = #t5.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*};
+    let final self::Test* #t6 = t in #t6.{self::Test::member} = #t6.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*};
+    self::B* v1 = t.{self::Test::member} = self::f<self::B*>();
+    self::B* v2 = let final self::Test* #t7 = t in let final self::B* #t8 = #t7.{self::Test::member}{self::B*} in #t8 == null ?{self::B*} #t7.{self::Test::member} = self::f<self::B*>() : #t8;
+    self::A* v3 = let final self::Test* #t9 = t in #t9.{self::Test::member} = #t9.{self::Test::member}{self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+    self::B* v4 = let final self::Test* #t10 = t in #t10.{self::Test::member} = #t10.{self::Test::member}{self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+    self::C* v5 = let final self::Test* #t11 = t in #t11.{self::Test::member} = #t11.{self::Test::member}{self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+    self::B* v6 = let final self::Test* #t12 = t in #t12.{self::Test::member} = #t12.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*};
+    self::B* v7 = let final self::Test* #t13 = t in let final self::B* #t14 = #t13.{self::Test::member}{self::B*} in let final self::B* #t15 = #t13.{self::Test::member} = #t14.{self::B::-}(1){(core::int*) →* self::B*} in #t14;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_property_null_aware.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_property_null_aware.dart.weak.modular.expect
new file mode 100644
index 0000000..681f9aa
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_property_null_aware.dart.weak.modular.expect
@@ -0,0 +1,72 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class Test extends core::Object {
+  field self::B* member = null;
+  synthetic constructor •() → self::Test*
+    : super core::Object::•()
+    ;
+  static method test(self::Test* t) → void {
+    let final self::Test* #t1 = t in #t1 == null ?{self::B*} null : #t1.{self::Test::member} = self::f<self::B*>();
+    let final self::Test* #t2 = t in #t2 == null ?{self::B*} null : #t2.{self::Test::member}{self::B*} == null ?{self::B*} #t2.{self::Test::member} = self::f<self::B*>() : null;
+    let final self::Test* #t3 = t in #t3 == null ?{self::A*} null : #t3.{self::Test::member} = #t3.{self::Test::member}{self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+    let final self::Test* #t4 = t in #t4 == null ?{self::B*} null : #t4.{self::Test::member} = #t4.{self::Test::member}{self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+    let final self::Test* #t5 = t in #t5 == null ?{self::C*} null : #t5.{self::Test::member} = #t5.{self::Test::member}{self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+    let final self::Test* #t6 = t in #t6 == null ?{self::B*} null : let final self::B* #t7 = #t6.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*} in let final void #t8 = #t6.{self::Test::member} = #t7 in #t7;
+    let final self::Test* #t9 = t in #t9 == null ?{self::B*} null : #t9.{self::Test::member} = #t9.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*};
+    self::B* v1 = let final self::Test* #t10 = t in #t10 == null ?{self::B*} null : #t10.{self::Test::member} = self::f<self::B*>();
+    self::B* v2 = let final self::Test* #t11 = t in #t11 == null ?{self::B*} null : let final self::B* #t12 = #t11.{self::Test::member}{self::B*} in #t12 == null ?{self::B*} #t11.{self::Test::member} = self::f<self::B*>() : #t12;
+    self::A* v3 = let final self::Test* #t13 = t in #t13 == null ?{self::A*} null : let final self::A* #t14 = #t13.{self::Test::member}{self::B*}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B* in let final void #t15 = #t13.{self::Test::member} = #t14 in #t14;
+    self::B* v4 = let final self::Test* #t16 = t in #t16 == null ?{self::B*} null : let final self::B* #t17 = #t16.{self::Test::member}{self::B*}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*} in let final void #t18 = #t16.{self::Test::member} = #t17 in #t17;
+    self::C* v5 = let final self::Test* #t19 = t in #t19 == null ?{self::C*} null : let final self::C* #t20 = #t19.{self::Test::member}{self::B*}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*} in let final void #t21 = #t19.{self::Test::member} = #t20 in #t20;
+    self::B* v6 = let final self::Test* #t22 = t in #t22 == null ?{self::B*} null : let final self::B* #t23 = #t22.{self::Test::member}{self::B*}.{self::B::-}(1){(core::int*) →* self::B*} in let final void #t24 = #t22.{self::Test::member} = #t23 in #t23;
+    self::B* v7 = let final self::Test* #t25 = t in #t25 == null ?{self::B*} null : let final self::B* #t26 = #t25.{self::Test::member}{self::B*} in let final void #t27 = #t25.{self::Test::member} = #t26.{self::B::-}(1){(core::int*) →* self::B*} in #t26;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_property_null_aware_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_property_null_aware_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..1e360b8
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_property_null_aware_upwards.dart.weak.modular.expect
@@ -0,0 +1,93 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Test1 extends core::Object {
+  field core::int* prop = null;
+  synthetic constructor •() → self::Test1*
+    : super core::Object::•()
+    ;
+  static method test(self::Test1* t) → void {
+    core::int* v1 = let final self::Test1* #t1 = t in #t1 == null ?{core::int*} null : #t1.{self::Test1::prop} = self::getInt();
+    core::num* v2 = let final self::Test1* #t2 = t in #t2 == null ?{core::num*} null : #t2.{self::Test1::prop} = self::getNum() as{TypeError} core::int*;
+    core::int* v4 = let final self::Test1* #t3 = t in #t3 == null ?{core::int*} null : let final core::int* #t4 = #t3.{self::Test1::prop}{core::int*} in #t4 == null ?{core::int*} #t3.{self::Test1::prop} = self::getInt() : #t4;
+    core::num* v5 = let final self::Test1* #t5 = t in #t5 == null ?{core::num*} null : let final core::int* #t6 = #t5.{self::Test1::prop}{core::int*} in #t6 == null ?{core::num*} #t5.{self::Test1::prop} = self::getNum() as{TypeError} core::int* : #t6;
+    core::int* v7 = let final self::Test1* #t7 = t in #t7 == null ?{core::int*} null : let final core::int* #t8 = #t7.{self::Test1::prop}{core::int*}.{core::num::+}(self::getInt()){(core::num*) →* core::int*} in let final void #t9 = #t7.{self::Test1::prop} = #t8 in #t8;
+    core::num* v8 = let final self::Test1* #t10 = t in #t10 == null ?{core::num*} null : let final core::num* #t11 = #t10.{self::Test1::prop}{core::int*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::int* in let final void #t12 = #t10.{self::Test1::prop} = #t11 in #t11;
+    core::int* v10 = let final self::Test1* #t13 = t in #t13 == null ?{core::int*} null : let final core::int* #t14 = #t13.{self::Test1::prop}{core::int*}.{core::num::+}(1){(core::num*) →* core::int*} in let final void #t15 = #t13.{self::Test1::prop} = #t14 in #t14;
+    core::int* v11 = let final self::Test1* #t16 = t in #t16 == null ?{core::int*} null : let final core::int* #t17 = #t16.{self::Test1::prop}{core::int*} in let final void #t18 = #t16.{self::Test1::prop} = #t17.{core::num::+}(1){(core::num*) →* core::int*} in #t17;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test2 extends core::Object {
+  field core::num* prop = null;
+  synthetic constructor •() → self::Test2*
+    : super core::Object::•()
+    ;
+  static method test(self::Test2* t) → void {
+    core::int* v1 = let final self::Test2* #t19 = t in #t19 == null ?{core::int*} null : #t19.{self::Test2::prop} = self::getInt();
+    core::num* v2 = let final self::Test2* #t20 = t in #t20 == null ?{core::num*} null : #t20.{self::Test2::prop} = self::getNum();
+    core::double* v3 = let final self::Test2* #t21 = t in #t21 == null ?{core::double*} null : #t21.{self::Test2::prop} = self::getDouble();
+    core::num* v4 = let final self::Test2* #t22 = t in #t22 == null ?{core::num*} null : let final core::num* #t23 = #t22.{self::Test2::prop}{core::num*} in #t23 == null ?{core::num*} #t22.{self::Test2::prop} = self::getInt() : #t23;
+    core::num* v5 = let final self::Test2* #t24 = t in #t24 == null ?{core::num*} null : let final core::num* #t25 = #t24.{self::Test2::prop}{core::num*} in #t25 == null ?{core::num*} #t24.{self::Test2::prop} = self::getNum() : #t25;
+    core::num* v6 = let final self::Test2* #t26 = t in #t26 == null ?{core::num*} null : let final core::num* #t27 = #t26.{self::Test2::prop}{core::num*} in #t27 == null ?{core::num*} #t26.{self::Test2::prop} = self::getDouble() : #t27;
+    core::num* v7 = let final self::Test2* #t28 = t in #t28 == null ?{core::num*} null : let final core::num* #t29 = #t28.{self::Test2::prop}{core::num*}.{core::num::+}(self::getInt()){(core::num*) →* core::num*} in let final void #t30 = #t28.{self::Test2::prop} = #t29 in #t29;
+    core::num* v8 = let final self::Test2* #t31 = t in #t31 == null ?{core::num*} null : let final core::num* #t32 = #t31.{self::Test2::prop}{core::num*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} in let final void #t33 = #t31.{self::Test2::prop} = #t32 in #t32;
+    core::num* v9 = let final self::Test2* #t34 = t in #t34 == null ?{core::num*} null : let final core::num* #t35 = #t34.{self::Test2::prop}{core::num*}.{core::num::+}(self::getDouble()){(core::num*) →* core::num*} in let final void #t36 = #t34.{self::Test2::prop} = #t35 in #t35;
+    core::num* v10 = let final self::Test2* #t37 = t in #t37 == null ?{core::num*} null : let final core::num* #t38 = #t37.{self::Test2::prop}{core::num*}.{core::num::+}(1){(core::num*) →* core::num*} in let final void #t39 = #t37.{self::Test2::prop} = #t38 in #t38;
+    core::num* v11 = let final self::Test2* #t40 = t in #t40 == null ?{core::num*} null : let final core::num* #t41 = #t40.{self::Test2::prop}{core::num*} in let final void #t42 = #t40.{self::Test2::prop} = #t41.{core::num::+}(1){(core::num*) →* core::num*} in #t41;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test3 extends core::Object {
+  field core::double* prop = null;
+  synthetic constructor •() → self::Test3*
+    : super core::Object::•()
+    ;
+  static method test3(self::Test3* t) → void {
+    core::num* v2 = let final self::Test3* #t43 = t in #t43 == null ?{core::num*} null : #t43.{self::Test3::prop} = self::getNum() as{TypeError} core::double*;
+    core::double* v3 = let final self::Test3* #t44 = t in #t44 == null ?{core::double*} null : #t44.{self::Test3::prop} = self::getDouble();
+    core::num* v5 = let final self::Test3* #t45 = t in #t45 == null ?{core::num*} null : let final core::double* #t46 = #t45.{self::Test3::prop}{core::double*} in #t46 == null ?{core::num*} #t45.{self::Test3::prop} = self::getNum() as{TypeError} core::double* : #t46;
+    core::double* v6 = let final self::Test3* #t47 = t in #t47 == null ?{core::double*} null : let final core::double* #t48 = #t47.{self::Test3::prop}{core::double*} in #t48 == null ?{core::double*} #t47.{self::Test3::prop} = self::getDouble() : #t48;
+    core::double* v7 = let final self::Test3* #t49 = t in #t49 == null ?{core::double*} null : let final core::double* #t50 = #t49.{self::Test3::prop}{core::double*}.{core::double::+}(self::getInt()){(core::num*) →* core::double*} in let final void #t51 = #t49.{self::Test3::prop} = #t50 in #t50;
+    core::double* v8 = let final self::Test3* #t52 = t in #t52 == null ?{core::double*} null : let final core::double* #t53 = #t52.{self::Test3::prop}{core::double*}.{core::double::+}(self::getNum()){(core::num*) →* core::double*} in let final void #t54 = #t52.{self::Test3::prop} = #t53 in #t53;
+    core::double* v9 = let final self::Test3* #t55 = t in #t55 == null ?{core::double*} null : let final core::double* #t56 = #t55.{self::Test3::prop}{core::double*}.{core::double::+}(self::getDouble()){(core::num*) →* core::double*} in let final void #t57 = #t55.{self::Test3::prop} = #t56 in #t56;
+    core::double* v10 = let final self::Test3* #t58 = t in #t58 == null ?{core::double*} null : let final core::double* #t59 = #t58.{self::Test3::prop}{core::double*}.{core::double::+}(1){(core::num*) →* core::double*} in let final void #t60 = #t58.{self::Test3::prop} = #t59 in #t59;
+    core::double* v11 = let final self::Test3* #t61 = t in #t61 == null ?{core::double*} null : let final core::double* #t62 = #t61.{self::Test3::prop}{core::double*} in let final void #t63 = #t61.{self::Test3::prop} = #t62.{core::double::+}(1){(core::num*) →* core::double*} in #t62;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method getInt() → core::int*
+  return 0;
+static method getNum() → core::num*
+  return 0;
+static method getDouble() → core::double*
+  return 0.0;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_property_super.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_property_super.dart.weak.modular.expect
new file mode 100644
index 0000000..28b3433
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_property_super.dart.weak.modular.expect
@@ -0,0 +1,77 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class Base extends core::Object {
+  field self::B* member = null;
+  synthetic constructor •() → self::Base*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test extends self::Base {
+  synthetic constructor •() → self::Test*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    super.{self::Base::member} = self::f<self::B*>();
+    super.{self::Base::member} == null ?{self::B*} super.{self::Base::member} = self::f<self::B*>() : null;
+    super.{self::Base::member} = super.{self::Base::member}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+    super.{self::Base::member} = super.{self::Base::member}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+    super.{self::Base::member} = super.{self::Base::member}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+    super.{self::Base::member} = super.{self::Base::member}.{self::B::-}(1){(core::int*) →* self::B*};
+    super.{self::Base::member} = super.{self::Base::member}.{self::B::-}(1){(core::int*) →* self::B*};
+    self::B* v1 = super.{self::Base::member} = self::f<self::B*>();
+    self::B* v2 = let final self::B* #t1 = super.{self::Base::member} in #t1 == null ?{self::B*} super.{self::Base::member} = self::f<self::B*>() : #t1;
+    self::A* v3 = super.{self::Base::member} = super.{self::Base::member}.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+    self::B* v4 = super.{self::Base::member} = super.{self::Base::member}.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+    self::C* v5 = super.{self::Base::member} = super.{self::Base::member}.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+    self::B* v6 = super.{self::Base::member} = super.{self::Base::member}.{self::B::-}(1){(core::int*) →* self::B*};
+    self::B* v7 = let final self::B* #t2 = super.{self::Base::member} in let final self::B* #t3 = super.{self::Base::member} = #t2.{self::B::-}(1){(core::int*) →* self::B*} in #t2;
+  }
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_property_super_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_property_super_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..4dec3f9
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_property_super_upwards.dart.weak.modular.expect
@@ -0,0 +1,78 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Base extends core::Object {
+  field core::int* intProp = null;
+  field core::num* numProp = null;
+  field core::double* doubleProp = null;
+  synthetic constructor •() → self::Base*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test1 extends self::Base {
+  synthetic constructor •() → self::Test1*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    core::int* v1 = super.{self::Base::intProp} = self::getInt();
+    core::num* v2 = super.{self::Base::intProp} = self::getNum() as{TypeError} core::int*;
+    core::int* v4 = let final core::int* #t1 = super.{self::Base::intProp} in #t1 == null ?{core::int*} super.{self::Base::intProp} = self::getInt() : #t1;
+    core::num* v5 = let final core::int* #t2 = super.{self::Base::intProp} in #t2 == null ?{core::num*} super.{self::Base::intProp} = self::getNum() as{TypeError} core::int* : #t2;
+    core::int* v7 = super.{self::Base::intProp} = super.{self::Base::intProp}.{core::num::+}(self::getInt()){(core::num*) →* core::int*};
+    core::num* v8 = super.{self::Base::intProp} = super.{self::Base::intProp}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::int*;
+    core::int* v10 = super.{self::Base::intProp} = super.{self::Base::intProp}.{core::num::+}(1){(core::num*) →* core::int*};
+    core::int* v11 = let final core::int* #t3 = super.{self::Base::intProp} in let final core::int* #t4 = super.{self::Base::intProp} = #t3.{core::num::+}(1){(core::num*) →* core::int*} in #t3;
+  }
+}
+class Test2 extends self::Base {
+  synthetic constructor •() → self::Test2*
+    : super self::Base::•()
+    ;
+  method test() → void {
+    core::int* v1 = super.{self::Base::numProp} = self::getInt();
+    core::num* v2 = super.{self::Base::numProp} = self::getNum();
+    core::double* v3 = super.{self::Base::numProp} = self::getDouble();
+    core::num* v4 = let final core::num* #t5 = super.{self::Base::numProp} in #t5 == null ?{core::num*} super.{self::Base::numProp} = self::getInt() : #t5;
+    core::num* v5 = let final core::num* #t6 = super.{self::Base::numProp} in #t6 == null ?{core::num*} super.{self::Base::numProp} = self::getNum() : #t6;
+    core::num* v6 = let final core::num* #t7 = super.{self::Base::numProp} in #t7 == null ?{core::num*} super.{self::Base::numProp} = self::getDouble() : #t7;
+    core::num* v7 = super.{self::Base::numProp} = super.{self::Base::numProp}.{core::num::+}(self::getInt()){(core::num*) →* core::num*};
+    core::num* v8 = super.{self::Base::numProp} = super.{self::Base::numProp}.{core::num::+}(self::getNum()){(core::num*) →* core::num*};
+    core::num* v9 = super.{self::Base::numProp} = super.{self::Base::numProp}.{core::num::+}(self::getDouble()){(core::num*) →* core::num*};
+    core::num* v10 = super.{self::Base::numProp} = super.{self::Base::numProp}.{core::num::+}(1){(core::num*) →* core::num*};
+    core::num* v11 = let final core::num* #t8 = super.{self::Base::numProp} in let final core::num* #t9 = super.{self::Base::numProp} = #t8.{core::num::+}(1){(core::num*) →* core::num*} in #t8;
+  }
+}
+class Test3 extends self::Base {
+  synthetic constructor •() → self::Test3*
+    : super self::Base::•()
+    ;
+  method test3() → void {
+    core::num* v2 = super.{self::Base::doubleProp} = self::getNum() as{TypeError} core::double*;
+    core::double* v3 = super.{self::Base::doubleProp} = self::getDouble();
+    core::num* v5 = let final core::double* #t10 = super.{self::Base::doubleProp} in #t10 == null ?{core::num*} super.{self::Base::doubleProp} = self::getNum() as{TypeError} core::double* : #t10;
+    core::double* v6 = let final core::double* #t11 = super.{self::Base::doubleProp} in #t11 == null ?{core::double*} super.{self::Base::doubleProp} = self::getDouble() : #t11;
+    core::double* v7 = super.{self::Base::doubleProp} = super.{self::Base::doubleProp}.{core::double::+}(self::getInt()){(core::num*) →* core::double*};
+    core::double* v8 = super.{self::Base::doubleProp} = super.{self::Base::doubleProp}.{core::double::+}(self::getNum()){(core::num*) →* core::double*};
+    core::double* v9 = super.{self::Base::doubleProp} = super.{self::Base::doubleProp}.{core::double::+}(self::getDouble()){(core::num*) →* core::double*};
+    core::double* v10 = super.{self::Base::doubleProp} = super.{self::Base::doubleProp}.{core::double::+}(1){(core::num*) →* core::double*};
+    core::double* v11 = let final core::double* #t12 = super.{self::Base::doubleProp} in let final core::double* #t13 = super.{self::Base::doubleProp} = #t12.{core::double::+}(1){(core::num*) →* core::double*} in #t12;
+  }
+}
+static method getInt() → core::int*
+  return 0;
+static method getNum() → core::num*
+  return 0;
+static method getDouble() → core::double*
+  return 0.0;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_property_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_property_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..f994d28
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_property_upwards.dart.weak.modular.expect
@@ -0,0 +1,93 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Test1 extends core::Object {
+  field core::int* prop = null;
+  synthetic constructor •() → self::Test1*
+    : super core::Object::•()
+    ;
+  static method test(self::Test1* t) → void {
+    core::int* v1 = t.{self::Test1::prop} = self::getInt();
+    core::num* v2 = t.{self::Test1::prop} = self::getNum() as{TypeError} core::int*;
+    core::int* v4 = let final self::Test1* #t1 = t in let final core::int* #t2 = #t1.{self::Test1::prop}{core::int*} in #t2 == null ?{core::int*} #t1.{self::Test1::prop} = self::getInt() : #t2;
+    core::num* v5 = let final self::Test1* #t3 = t in let final core::int* #t4 = #t3.{self::Test1::prop}{core::int*} in #t4 == null ?{core::num*} #t3.{self::Test1::prop} = self::getNum() as{TypeError} core::int* : #t4;
+    core::int* v7 = let final self::Test1* #t5 = t in #t5.{self::Test1::prop} = #t5.{self::Test1::prop}{core::int*}.{core::num::+}(self::getInt()){(core::num*) →* core::int*};
+    core::num* v8 = let final self::Test1* #t6 = t in #t6.{self::Test1::prop} = #t6.{self::Test1::prop}{core::int*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::int*;
+    core::int* v10 = let final self::Test1* #t7 = t in #t7.{self::Test1::prop} = #t7.{self::Test1::prop}{core::int*}.{core::num::+}(1){(core::num*) →* core::int*};
+    core::int* v11 = let final self::Test1* #t8 = t in let final core::int* #t9 = #t8.{self::Test1::prop}{core::int*} in let final core::int* #t10 = #t8.{self::Test1::prop} = #t9.{core::num::+}(1){(core::num*) →* core::int*} in #t9;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test2 extends core::Object {
+  field core::num* prop = null;
+  synthetic constructor •() → self::Test2*
+    : super core::Object::•()
+    ;
+  static method test(self::Test2* t) → void {
+    core::int* v1 = t.{self::Test2::prop} = self::getInt();
+    core::num* v2 = t.{self::Test2::prop} = self::getNum();
+    core::double* v3 = t.{self::Test2::prop} = self::getDouble();
+    core::num* v4 = let final self::Test2* #t11 = t in let final core::num* #t12 = #t11.{self::Test2::prop}{core::num*} in #t12 == null ?{core::num*} #t11.{self::Test2::prop} = self::getInt() : #t12;
+    core::num* v5 = let final self::Test2* #t13 = t in let final core::num* #t14 = #t13.{self::Test2::prop}{core::num*} in #t14 == null ?{core::num*} #t13.{self::Test2::prop} = self::getNum() : #t14;
+    core::num* v6 = let final self::Test2* #t15 = t in let final core::num* #t16 = #t15.{self::Test2::prop}{core::num*} in #t16 == null ?{core::num*} #t15.{self::Test2::prop} = self::getDouble() : #t16;
+    core::num* v7 = let final self::Test2* #t17 = t in #t17.{self::Test2::prop} = #t17.{self::Test2::prop}{core::num*}.{core::num::+}(self::getInt()){(core::num*) →* core::num*};
+    core::num* v8 = let final self::Test2* #t18 = t in #t18.{self::Test2::prop} = #t18.{self::Test2::prop}{core::num*}.{core::num::+}(self::getNum()){(core::num*) →* core::num*};
+    core::num* v9 = let final self::Test2* #t19 = t in #t19.{self::Test2::prop} = #t19.{self::Test2::prop}{core::num*}.{core::num::+}(self::getDouble()){(core::num*) →* core::num*};
+    core::num* v10 = let final self::Test2* #t20 = t in #t20.{self::Test2::prop} = #t20.{self::Test2::prop}{core::num*}.{core::num::+}(1){(core::num*) →* core::num*};
+    core::num* v11 = let final self::Test2* #t21 = t in let final core::num* #t22 = #t21.{self::Test2::prop}{core::num*} in let final core::num* #t23 = #t21.{self::Test2::prop} = #t22.{core::num::+}(1){(core::num*) →* core::num*} in #t22;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Test3 extends core::Object {
+  field core::double* prop = null;
+  synthetic constructor •() → self::Test3*
+    : super core::Object::•()
+    ;
+  static method test3(self::Test3* t) → void {
+    core::num* v2 = t.{self::Test3::prop} = self::getNum() as{TypeError} core::double*;
+    core::double* v3 = t.{self::Test3::prop} = self::getDouble();
+    core::num* v5 = let final self::Test3* #t24 = t in let final core::double* #t25 = #t24.{self::Test3::prop}{core::double*} in #t25 == null ?{core::num*} #t24.{self::Test3::prop} = self::getNum() as{TypeError} core::double* : #t25;
+    core::double* v6 = let final self::Test3* #t26 = t in let final core::double* #t27 = #t26.{self::Test3::prop}{core::double*} in #t27 == null ?{core::double*} #t26.{self::Test3::prop} = self::getDouble() : #t27;
+    core::double* v7 = let final self::Test3* #t28 = t in #t28.{self::Test3::prop} = #t28.{self::Test3::prop}{core::double*}.{core::double::+}(self::getInt()){(core::num*) →* core::double*};
+    core::double* v8 = let final self::Test3* #t29 = t in #t29.{self::Test3::prop} = #t29.{self::Test3::prop}{core::double*}.{core::double::+}(self::getNum()){(core::num*) →* core::double*};
+    core::double* v9 = let final self::Test3* #t30 = t in #t30.{self::Test3::prop} = #t30.{self::Test3::prop}{core::double*}.{core::double::+}(self::getDouble()){(core::num*) →* core::double*};
+    core::double* v10 = let final self::Test3* #t31 = t in #t31.{self::Test3::prop} = #t31.{self::Test3::prop}{core::double*}.{core::double::+}(1){(core::num*) →* core::double*};
+    core::double* v11 = let final self::Test3* #t32 = t in let final core::double* #t33 = #t32.{self::Test3::prop}{core::double*} in let final core::double* #t34 = #t32.{self::Test3::prop} = #t33.{core::double::+}(1){(core::num*) →* core::double*} in #t33;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method getInt() → core::int*
+  return 0;
+static method getNum() → core::num*
+  return 0;
+static method getDouble() → core::double*
+  return 0.0;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_ref.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_ref.dart.weak.modular.expect
new file mode 100644
index 0000000..e2c5e19
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_ref.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* f = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::A* a = new self::A::•();
+static field core::int* b = self::a.{self::A::f} = 1;
+static field core::int* c = 0;
+static field core::int* d = self::c = 1;
+static method main() → dynamic {
+  self::a;
+  self::b;
+  self::c;
+  self::d;
+}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_static.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_static.dart.weak.modular.expect
new file mode 100644
index 0000000..090413f
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_static.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  static field self::B* staticVariable = null;
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(self::C* v) → self::A*
+    return null;
+  operator -(core::int* i) → self::B*
+    return null;
+  operator *(self::B* v) → self::B*
+    return null;
+  operator &(self::A* v) → self::C*
+    return null;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+static field self::B* topLevelVariable;
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method test_topLevelVariable() → void {
+  self::topLevelVariable = self::f<self::B*>();
+  self::topLevelVariable == null ?{self::B*} self::topLevelVariable = self::f<self::B*>() : null;
+  self::topLevelVariable = self::topLevelVariable.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+  self::topLevelVariable = self::topLevelVariable.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+  self::topLevelVariable = self::topLevelVariable.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+  self::topLevelVariable = self::topLevelVariable.{self::B::-}(1){(core::int*) →* self::B*};
+  self::topLevelVariable = self::topLevelVariable.{self::B::-}(1){(core::int*) →* self::B*};
+  self::B* v1 = self::topLevelVariable = self::f<self::B*>();
+  self::B* v2 = let final self::B* #t1 = self::topLevelVariable in #t1 == null ?{self::B*} self::topLevelVariable = self::f<self::B*>() : #t1;
+  self::A* v3 = self::topLevelVariable = self::topLevelVariable.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+  self::B* v4 = self::topLevelVariable = self::topLevelVariable.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+  self::C* v5 = self::topLevelVariable = self::topLevelVariable.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+  self::B* v6 = self::topLevelVariable = self::topLevelVariable.{self::B::-}(1){(core::int*) →* self::B*};
+  self::B* v7 = let final self::B* #t2 = self::topLevelVariable in let final self::B* #t3 = self::topLevelVariable = #t2.{self::B::-}(1){(core::int*) →* self::B*} in #t2;
+}
+static method test_staticVariable() → void {
+  self::B::staticVariable = self::f<self::B*>();
+  self::B::staticVariable == null ?{self::B*} self::B::staticVariable = self::f<self::B*>() : null;
+  self::B::staticVariable = self::B::staticVariable.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+  self::B::staticVariable = self::B::staticVariable.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+  self::B::staticVariable = self::B::staticVariable.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+  self::B::staticVariable = self::B::staticVariable.{self::B::-}(1){(core::int*) →* self::B*};
+  self::B::staticVariable = self::B::staticVariable.{self::B::-}(1){(core::int*) →* self::B*};
+  self::B* v1 = self::B::staticVariable = self::f<self::B*>();
+  self::B* v2 = let final self::B* #t4 = self::B::staticVariable in #t4 == null ?{self::B*} self::B::staticVariable = self::f<self::B*>() : #t4;
+  self::A* v3 = self::B::staticVariable = self::B::staticVariable.{self::B::+}(self::f<self::C*>()){(self::C*) →* self::A*} as{TypeError} self::B*;
+  self::B* v4 = self::B::staticVariable = self::B::staticVariable.{self::B::*}(self::f<self::B*>()){(self::B*) →* self::B*};
+  self::C* v5 = self::B::staticVariable = self::B::staticVariable.{self::B::&}(self::f<self::A*>()){(self::A*) →* self::C*};
+  self::B* v6 = self::B::staticVariable = self::B::staticVariable.{self::B::-}(1){(core::int*) →* self::B*};
+  self::B* v7 = let final self::B* #t5 = self::B::staticVariable in let final self::B* #t6 = self::B::staticVariable = #t5.{self::B::-}(1){(core::int*) →* self::B*} in #t5;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_assign_to_static_upwards.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_assign_to_static_upwards.dart.weak.modular.expect
new file mode 100644
index 0000000..ae43fd0
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_assign_to_static_upwards.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::int* topLevelInt;
+static field core::num* topLevelNum;
+static field core::double* topLevelDouble;
+static method getInt() → core::int*
+  return 0;
+static method getNum() → core::num*
+  return 0;
+static method getDouble() → core::double*
+  return 0.0;
+static method test1() → void {
+  core::int* v1 = self::topLevelInt = self::getInt();
+  core::num* v2 = self::topLevelInt = self::getNum() as{TypeError} core::int*;
+  core::int* v4 = let final core::int* #t1 = self::topLevelInt in #t1 == null ?{core::int*} self::topLevelInt = self::getInt() : #t1;
+  core::num* v5 = let final core::int* #t2 = self::topLevelInt in #t2 == null ?{core::num*} self::topLevelInt = self::getNum() as{TypeError} core::int* : #t2;
+  core::int* v7 = self::topLevelInt = self::topLevelInt.{core::num::+}(self::getInt()){(core::num*) →* core::int*};
+  core::num* v8 = self::topLevelInt = self::topLevelInt.{core::num::+}(self::getNum()){(core::num*) →* core::num*} as{TypeError} core::int*;
+  core::int* v10 = self::topLevelInt = self::topLevelInt.{core::num::+}(1){(core::num*) →* core::int*};
+  core::int* v11 = let final core::int* #t3 = self::topLevelInt in let final core::int* #t4 = self::topLevelInt = #t3.{core::num::+}(1){(core::num*) →* core::int*} in #t3;
+}
+static method test2() → void {
+  core::int* v1 = self::topLevelNum = self::getInt();
+  core::num* v2 = self::topLevelNum = self::getNum();
+  core::double* v3 = self::topLevelNum = self::getDouble();
+  core::num* v4 = let final core::num* #t5 = self::topLevelNum in #t5 == null ?{core::num*} self::topLevelNum = self::getInt() : #t5;
+  core::num* v5 = let final core::num* #t6 = self::topLevelNum in #t6 == null ?{core::num*} self::topLevelNum = self::getNum() : #t6;
+  core::num* v6 = let final core::num* #t7 = self::topLevelNum in #t7 == null ?{core::num*} self::topLevelNum = self::getDouble() : #t7;
+  core::num* v7 = self::topLevelNum = self::topLevelNum.{core::num::+}(self::getInt()){(core::num*) →* core::num*};
+  core::num* v8 = self::topLevelNum = self::topLevelNum.{core::num::+}(self::getNum()){(core::num*) →* core::num*};
+  core::num* v9 = self::topLevelNum = self::topLevelNum.{core::num::+}(self::getDouble()){(core::num*) →* core::num*};
+  core::num* v10 = self::topLevelNum = self::topLevelNum.{core::num::+}(1){(core::num*) →* core::num*};
+  core::num* v11 = let final core::num* #t8 = self::topLevelNum in let final core::num* #t9 = self::topLevelNum = #t8.{core::num::+}(1){(core::num*) →* core::num*} in #t8;
+}
+static method test3() → void {
+  core::num* v2 = self::topLevelDouble = self::getNum() as{TypeError} core::double*;
+  core::double* v3 = self::topLevelDouble = self::getDouble();
+  core::num* v5 = let final core::double* #t10 = self::topLevelDouble in #t10 == null ?{core::num*} self::topLevelDouble = self::getNum() as{TypeError} core::double* : #t10;
+  core::double* v6 = let final core::double* #t11 = self::topLevelDouble in #t11 == null ?{core::double*} self::topLevelDouble = self::getDouble() : #t11;
+  core::double* v7 = self::topLevelDouble = self::topLevelDouble.{core::double::+}(self::getInt()){(core::num*) →* core::double*};
+  core::double* v8 = self::topLevelDouble = self::topLevelDouble.{core::double::+}(self::getNum()){(core::num*) →* core::double*};
+  core::double* v9 = self::topLevelDouble = self::topLevelDouble.{core::double::+}(self::getDouble()){(core::num*) →* core::double*};
+  core::double* v10 = self::topLevelDouble = self::topLevelDouble.{core::double::+}(1){(core::num*) →* core::double*};
+  core::double* v11 = let final core::double* #t12 = self::topLevelDouble in let final core::double* #t13 = self::topLevelDouble = #t12.{core::double::+}(1){(core::num*) →* core::double*} in #t12;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_field_getter_setter_mismatch.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_field_getter_setter_mismatch.dart.weak.modular.expect
new file mode 100644
index 0000000..871301b
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_field_getter_setter_mismatch.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/infer_field_getter_setter_mismatch.dart:16:7: Error: Can't infer a type for 'x' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var x;
+//       ^
+// pkg/front_end/testcases/inference_new/infer_field_getter_setter_mismatch.dart:9:11: Context: This is one of the overridden members.
+//   int get x;
+//           ^
+// pkg/front_end/testcases/inference_new/infer_field_getter_setter_mismatch.dart:10:12: Context: This is one of the overridden members.
+//   void set x(double value);
+//            ^
+//
+// pkg/front_end/testcases/inference_new/infer_field_getter_setter_mismatch.dart:9:11: Error: The type 'int' of the getter 'A.x' is not assignable to the type 'double' of the setter 'A.x'.
+//   int get x;
+//           ^
+// pkg/front_end/testcases/inference_new/infer_field_getter_setter_mismatch.dart:10:12: Context: This is the declaration of the setter 'A.x'.
+//   void set x(double value);
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::int*;
+  abstract set x(core::double* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  field invalid-type x = null;
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_field_override_accessors.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_field_override_accessors.dart.weak.modular.expect
new file mode 100644
index 0000000..497e214
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_field_override_accessors.dart.weak.modular.expect
@@ -0,0 +1,61 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/infer_field_override_accessors.dart:16:7: Error: Can't infer a type for 'x' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var x;
+//       ^
+// pkg/front_end/testcases/inference_new/infer_field_override_accessors.dart:6:9: Context: This is one of the overridden members.
+//   A get x;
+//         ^
+// pkg/front_end/testcases/inference_new/infer_field_override_accessors.dart:7:12: Context: This is one of the overridden members.
+//   void set x(B value);
+//            ^
+//
+// pkg/front_end/testcases/inference_new/infer_field_override_accessors.dart:17:7: Error: Can't infer a type for 'y' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var y;
+//       ^
+// pkg/front_end/testcases/inference_new/infer_field_override_accessors.dart:9:9: Context: This is one of the overridden members.
+//   B get y;
+//         ^
+// pkg/front_end/testcases/inference_new/infer_field_override_accessors.dart:10:12: Context: This is one of the overridden members.
+//   void set y(A value);
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract get x() → self::A*;
+  abstract set x(self::B* value) → void;
+  abstract get y() → self::B*;
+  abstract set y(self::A* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C extends self::B {
+  field invalid-type x = null;
+  field invalid-type y = null;
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_field_override_getter_overrides_setter.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_field_override_getter_overrides_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..6282349
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_field_override_getter_overrides_setter.dart.weak.modular.expect
@@ -0,0 +1,47 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/infer_field_override_getter_overrides_setter.dart:19:7: Error: Can't infer a type for 'x' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var x;
+//       ^
+// pkg/front_end/testcases/inference_new/infer_field_override_getter_overrides_setter.dart:13:11: Context: This is one of the overridden members.
+//   int get x;
+//           ^
+// pkg/front_end/testcases/inference_new/infer_field_override_getter_overrides_setter.dart:9:12: Context: This is one of the overridden members.
+//   void set x(num value);
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract set x(core::num* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  abstract get x() → core::int*;
+}
+class C extends self::B {
+  field invalid-type x = null;
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_field_override_setter_overrides_getter.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_field_override_setter_overrides_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..001d19d
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_field_override_setter_overrides_getter.dart.weak.modular.expect
@@ -0,0 +1,47 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/infer_field_override_setter_overrides_getter.dart:19:7: Error: Can't infer a type for 'x' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var x;
+//       ^
+// pkg/front_end/testcases/inference_new/infer_field_override_setter_overrides_getter.dart:9:11: Context: This is one of the overridden members.
+//   num get x;
+//           ^
+// pkg/front_end/testcases/inference_new/infer_field_override_setter_overrides_getter.dart:13:12: Context: This is one of the overridden members.
+//   void set x(int value);
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract get x() → core::num*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  abstract set x(core::int* value) → void;
+}
+class C extends self::B {
+  field invalid-type x = null;
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_instance_accessor_ref.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_instance_accessor_ref.dart.weak.modular.expect
new file mode 100644
index 0000000..ea950c6
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_instance_accessor_ref.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field self::B* b = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  get c() → self::C*
+    return null;
+  set c(self::C* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+}
+static field self::A* a = new self::A::•();
+static field self::C* x = self::a.{self::A::b}{self::B*}.{self::B::c}{self::C*};
+static field self::C* y = let final self::B* #t1 = self::a.{self::A::b}{self::B*} in let final self::C* #t2 = #t1.{self::B::c}{self::C*} in #t2 == null ?{self::C*} #t1.{self::B::c} = new self::D::•() : #t2;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_instance_field_ref.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_instance_field_ref.dart.weak.modular.expect
new file mode 100644
index 0000000..b174194
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_instance_field_ref.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field self::B* b = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  field self::C* c = null;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+}
+static field self::A* a = new self::A::•();
+static field self::C* x = self::a.{self::A::b}{self::B*}.{self::B::c}{self::C*};
+static field self::C* y = let final self::B* #t1 = self::a.{self::A::b}{self::B*} in let final self::C* #t2 = #t1.{self::B::c}{self::C*} in #t2 == null ?{self::C*} #t1.{self::B::c} = new self::D::•() : #t2;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_instance_field_ref_circular.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_instance_field_ref_circular.dart.weak.modular.expect
new file mode 100644
index 0000000..21df0fc
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_instance_field_ref_circular.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/infer_instance_field_ref_circular.dart:11:7: Error: Can't infer the type of 'b': circularity found during type inference.
+// Specify the type explicitly.
+//   var b = /*@ returnType=() ->* invalid-type */ () => x;
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field invalid-type b = () → () →* invalid-type => self::x;
+  field () →* () →* invalid-type c = () → () →* invalid-type => self::x;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::A* a = new self::A::•();
+static field () →* invalid-type x = () → invalid-type => self::a.{self::A::b}{invalid-type};
+static field () →* () →* () →* invalid-type y = () → () →* () →* invalid-type => self::a.{self::A::c}{() →* () →* invalid-type};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_logical.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_logical.dart.weak.modular.expect
new file mode 100644
index 0000000..2b05154
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_logical.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::bool* x = self::f<core::bool*>() || self::f<core::bool*>();
+static field core::bool* y = self::f<core::bool*>() && self::f<core::bool*>();
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method test() → void {
+  core::bool* x = self::f<core::bool*>() || self::f<core::bool*>();
+  core::bool* y = self::f<core::bool*>() && self::f<core::bool*>();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/infer_use_of_void.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/infer_use_of_void.dart.weak.modular.expect
new file mode 100644
index 0000000..18cf625
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/infer_use_of_void.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method f() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  method f() → void {}
+}
+static field void x = new self::C::•().{self::C::f}(){() →* void};
+static method main() → dynamic {
+  self::x;
+}
diff --git a/pkg/front_end/testcases/inference_new/invalid_assignment_during_toplevel_inference.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/invalid_assignment_during_toplevel_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..3faad32
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/invalid_assignment_during_toplevel_inference.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/invalid_assignment_during_toplevel_inference.dart:9:13: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+// var x = i = s;
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field core::int* i;
+static field core::String* s;
+static field core::String* x = self::i = invalid-expression "pkg/front_end/testcases/inference_new/invalid_assignment_during_toplevel_inference.dart:9:13: Error: A value of type 'String' can't be assigned to a variable of type 'int'.
+var x = i = s;
+            ^" in self::s as{TypeError} core::int*;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/list_literals_can_infer_null_top_level.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/list_literals_can_infer_null_top_level.dart.weak.modular.expect
new file mode 100644
index 0000000..30af47a
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/list_literals_can_infer_null_top_level.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<Null>* x = <Null>[null];
+static method main() → dynamic {
+  self::x;
+}
diff --git a/pkg/front_end/testcases/inference_new/map_literals_can_infer_null_top_level.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/map_literals_can_infer_null_top_level.dart.weak.modular.expect
new file mode 100644
index 0000000..c5b6db9
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/map_literals_can_infer_null_top_level.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::Map<Null, Null>* x = <Null, Null>{null: null};
+static method main() → dynamic {
+  self::x;
+}
diff --git a/pkg/front_end/testcases/inference_new/multiple_interface_inheritance.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/multiple_interface_inheritance.dart.weak.modular.expect
new file mode 100644
index 0000000..35f8118
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/multiple_interface_inheritance.dart.weak.modular.expect
@@ -0,0 +1,89 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class I1 extends core::Object {
+  synthetic constructor •() → self::I1*
+    : super core::Object::•()
+    ;
+  abstract method f(core::int* i) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I2 extends core::Object {
+  synthetic constructor •() → self::I2*
+    : super core::Object::•()
+    ;
+  abstract method f(core::Object* o) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends core::Object implements self::I1, self::I2 {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature method f(core::Object* o) → void; -> self::I2::f
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method f(core::Object* o) → void {}
+}
+abstract class E extends core::Object implements self::I2, self::I1 {
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F extends self::E {
+  synthetic constructor •() → self::F*
+    : super self::E::•()
+    ;
+  method f(core::Object* o) → void {}
+}
+static method g1(self::C* c) → void {
+  c.{self::C::f}("hi"){(core::Object*) →* void};
+}
+static method g2(self::E* e) → void {
+  e.{self::I2::f}("hi"){(core::Object*) →* void};
+}
+static method main() → dynamic {
+  self::g1(new self::D::•());
+  self::g2(new self::F::•());
+}
diff --git a/pkg/front_end/testcases/inference_new/null_aware_property_get.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/null_aware_property_get.dart.weak.modular.expect
new file mode 100644
index 0000000..fa63c03
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/null_aware_property_get.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  method method<T extends core::Object* = dynamic>() → self::Class::method::T*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::Class* c;
+  () →* core::num* f = let final self::Class* #t1 = c in #t1 == null ?{() →* core::num*} null : #t1.{self::Class::method}{<T extends core::Object* = dynamic>() →* T*}<core::num*>;
+}
diff --git a/pkg/front_end/testcases/inference_new/property_assign_combiner.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/property_assign_combiner.dart.weak.modular.expect
new file mode 100644
index 0000000..facdace
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/property_assign_combiner.dart.weak.modular.expect
@@ -0,0 +1,137 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/property_assign_combiner.dart:29:9: Error: The type 'A' of the getter 'G.target' is not assignable to the type 'B' of the setter 'G.target'.
+//  - 'A' is from 'pkg/front_end/testcases/inference_new/property_assign_combiner.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/inference_new/property_assign_combiner.dart'.
+//   A get target => null;
+//         ^^^^^^
+// pkg/front_end/testcases/inference_new/property_assign_combiner.dart:31:12: Context: This is the declaration of the setter 'G.target'.
+//   void set target(B value) {}
+//            ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator +(core::int* value) → self::C*
+    return null;
+  operator *(self::D* value) → self::C*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  operator +(core::int* value) → self::E*
+    return null;
+  operator *(self::F* value) → self::E*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E extends core::Object {
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F extends core::Object {
+  synthetic constructor •() → self::F*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class G extends core::Object {
+  synthetic constructor •() → self::G*
+    : super core::Object::•()
+    ;
+  get target() → self::A*
+    return null;
+  set target(self::B* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method test1(self::G* g) → void {
+  let final self::G* #t1 = g in #t1.{self::G::target} = #t1.{self::G::target}{self::A*}.{self::A::*}(self::f<self::D*>()){(self::D*) →* self::C*};
+  self::C* x = let final self::G* #t2 = g in #t2.{self::G::target} = #t2.{self::G::target}{self::A*}.{self::A::*}(self::f<self::D*>()){(self::D*) →* self::C*};
+}
+static method test2(self::G* g) → void {
+  let final self::G* #t3 = g in #t3.{self::G::target} = #t3.{self::G::target}{self::A*}.{self::A::+}(1){(core::int*) →* self::C*};
+  self::C* x = let final self::G* #t4 = g in #t4.{self::G::target} = #t4.{self::G::target}{self::A*}.{self::A::+}(1){(core::int*) →* self::C*};
+}
+static method test3(self::G* g) → void {
+  let final self::G* #t5 = g in #t5.{self::G::target} = #t5.{self::G::target}{self::A*}.{self::A::+}(1){(core::int*) →* self::C*};
+  self::A* x = let final self::G* #t6 = g in let final self::A* #t7 = #t6.{self::G::target}{self::A*} in let final self::C* #t8 = #t6.{self::G::target} = #t7.{self::A::+}(1){(core::int*) →* self::C*} in #t7;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/property_get_toplevel.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/property_get_toplevel.dart.weak.modular.expect
new file mode 100644
index 0000000..d52af61
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/property_get_toplevel.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field core::int* field = 0;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  get getter() → core::int*
+    return 0;
+  method function() → core::int*
+    return 0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C* c = new self::C::•();
+static field core::int* field_ref = self::c.{self::C::field}{core::int*};
+static field core::int* getter_ref = self::c.{self::C::getter}{core::int*};
+static field () →* core::int* function_ref = self::c.{self::C::function}{() →* core::int*};
+static field core::List<core::int*>* field_ref_list = <core::int*>[self::c.{self::C::field}{core::int*}];
+static field core::List<core::int*>* getter_ref_list = <core::int*>[self::c.{self::C::getter}{core::int*}];
+static field core::List<() →* core::int*>* function_ref_list = <() →* core::int*>[self::c.{self::C::function}{() →* core::int*}];
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/static_assign_combiner.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/static_assign_combiner.dart.weak.modular.expect
new file mode 100644
index 0000000..0c920ee
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/static_assign_combiner.dart.weak.modular.expect
@@ -0,0 +1,122 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/static_assign_combiner.dart:28:7: Error: The type 'A' of the getter 'target' is not assignable to the type 'B' of the setter 'target'.
+//  - 'A' is from 'pkg/front_end/testcases/inference_new/static_assign_combiner.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/inference_new/static_assign_combiner.dart'.
+// A get target => null;
+//       ^^^^^^
+// pkg/front_end/testcases/inference_new/static_assign_combiner.dart:30:10: Context: This is the declaration of the setter 'target'.
+// void set target(B value) {}
+//          ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator +(core::int* value) → self::C*
+    return null;
+  operator *(self::D* value) → self::C*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  operator +(core::int* value) → self::E*
+    return null;
+  operator *(self::F* value) → self::E*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E extends core::Object {
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F extends core::Object {
+  synthetic constructor •() → self::F*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static get target() → self::A*
+  return null;
+static set target(self::B* value) → void {}
+static method test1() → void {
+  self::target = self::target.{self::A::*}(self::f<self::D*>()){(self::D*) →* self::C*};
+  self::C* x = self::target = self::target.{self::A::*}(self::f<self::D*>()){(self::D*) →* self::C*};
+}
+static method test2() → void {
+  self::target = self::target.{self::A::+}(1){(core::int*) →* self::C*};
+  self::C* x = self::target = self::target.{self::A::+}(1){(core::int*) →* self::C*};
+}
+static method test3() → void {
+  self::target = self::target.{self::A::+}(1){(core::int*) →* self::C*};
+  self::A* x = let final self::A* #t1 = self::target in let final self::C* #t2 = self::target = #t1.{self::A::+}(1){(core::int*) →* self::C*} in #t1;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/strongly_connected_component.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/strongly_connected_component.dart.weak.modular.expect
new file mode 100644
index 0000000..276a1c2
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/strongly_connected_component.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/inference_new/strongly_connected_component.dart:17:5: Error: Can't infer the type of 'x': circularity found during type inference.
+// Specify the type explicitly.
+// var x = /*@ returnType=() ->* invalid-type */ () => f() ? y : z;
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field invalid-type x = () → () →* invalid-type => self::f() ?{() →* invalid-type} self::y : self::z;
+static field () →* invalid-type y = () → invalid-type => self::x;
+static field () →* invalid-type z = () → invalid-type => self::x;
+static method f() → core::bool*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/super_index_get.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/super_index_get.dart.weak.modular.expect
new file mode 100644
index 0000000..2910dae
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/super_index_get.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  operator [](core::int* x) → core::num*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  operator [](core::Object* x) → core::int*
+    return null;
+  method h() → void {
+    core::num* x = super.{self::B::[]}(self::f<core::int*>());
+  }
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/super_index_get_substitution.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/super_index_get_substitution.dart.weak.modular.expect
new file mode 100644
index 0000000..b2841e6
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/super_index_get_substitution.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library test;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class D<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E<T extends core::Object* = dynamic> extends self::D<self::E::T*> {
+  synthetic constructor •() → self::E<self::E::T*>*
+    : super self::D::•()
+    ;
+}
+class B<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  operator [](covariant-by-class self::E<self::B::T*>* x) → self::D<self::B::T*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<U extends core::Object* = dynamic> extends self::B<asy::Future<self::C::U*>*> {
+  synthetic constructor •() → self::C<self::C::U*>*
+    : super self::B::•()
+    ;
+  operator [](covariant-by-class core::Object* x) → self::E<asy::Future<self::C::U*>*>*
+    return null;
+  method h() → void {
+    self::D<asy::Future<self::C::U*>*>* x = super.{self::B::[]}(self::f<self::E<asy::Future<self::C::U*>*>*>());
+  }
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/switch.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/switch.dart.weak.modular.expect
new file mode 100644
index 0000000..6e55000
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/switch.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method test(self::C<core::int*>* x) → void {
+  #L1:
+  switch(x) {
+    #L2:
+    case #C1:
+      {
+        core::int* y = 0;
+        break #L1;
+      }
+    #L3:
+    default:
+      {
+        core::int* y = 0;
+        break #L1;
+      }
+  }
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::C<core::int*> {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///switch.dart:
+- C. (from org-dartlang-testcase:///switch.dart:11:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/inference_new/top_level_field_depends_on_multiple_inheritance.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/top_level_field_depends_on_multiple_inheritance.dart.weak.modular.expect
new file mode 100644
index 0000000..69cac39
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/top_level_field_depends_on_multiple_inheritance.dart.weak.modular.expect
@@ -0,0 +1,104 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+abstract class D extends core::Object {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract method foo() → self::A*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class E extends core::Object {
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  abstract method foo() → self::B*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class F extends core::Object {
+  synthetic constructor •() → self::F*
+    : super core::Object::•()
+    ;
+  abstract method foo() → core::Object*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class G extends core::Object implements self::D, self::E, self::F {
+  synthetic constructor •() → self::G*
+    : super core::Object::•()
+    ;
+  abstract member-signature method foo() → self::B*; -> self::E::foo
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class H extends self::G {
+  synthetic constructor •() → self::H*
+    : super self::G::•()
+    ;
+  method foo() → self::C*
+    return new self::C::•();
+}
+static field self::B* x = self::bar().{self::G::foo}(){() →* self::B*};
+static method bar() → self::G*
+  return new self::H::•();
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/inference_new/unsafe_block_closure_inference_function_call_explicit_dynamic_param_via_expr2.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/unsafe_block_closure_inference_function_call_explicit_dynamic_param_via_expr2.dart.weak.modular.expect
new file mode 100644
index 0000000..26fdda1
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/unsafe_block_closure_inference_function_call_explicit_dynamic_param_via_expr2.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<core::int*>* v = #C1<core::int*>(() → core::int* {
+  return 1;
+}){(() →* core::int*) →* core::List<core::int*>*};
+static method f<T extends core::Object* = dynamic>(() →* self::f::T* g) → core::List<self::f::T*>*
+  return <self::f::T*>[g(){() →* self::f::T*}];
+static method main() → dynamic {
+  self::v;
+}
+
+constants  {
+  #C1 = static-tearoff self::f
+}
diff --git a/pkg/front_end/testcases/inference_new/unsafe_block_closure_inference_function_call_explicit_type_param_via_expr2.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/unsafe_block_closure_inference_function_call_explicit_type_param_via_expr2.dart.weak.modular.expect
new file mode 100644
index 0000000..26fdda1
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/unsafe_block_closure_inference_function_call_explicit_type_param_via_expr2.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<core::int*>* v = #C1<core::int*>(() → core::int* {
+  return 1;
+}){(() →* core::int*) →* core::List<core::int*>*};
+static method f<T extends core::Object* = dynamic>(() →* self::f::T* g) → core::List<self::f::T*>*
+  return <self::f::T*>[g(){() →* self::f::T*}];
+static method main() → dynamic {
+  self::v;
+}
+
+constants  {
+  #C1 = static-tearoff self::f
+}
diff --git a/pkg/front_end/testcases/inference_new/void_return_type_subtypes_dynamic.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/void_return_type_subtypes_dynamic.dart.weak.modular.expect
new file mode 100644
index 0000000..96e59b9
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/void_return_type_subtypes_dynamic.dart.weak.modular.expect
@@ -0,0 +1,19 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static field void y = self::run<void>(#C1);
+static method run<T extends core::Object* = dynamic>(() →* self::run::T* f) → self::run::T* {
+  core::print("running");
+  self::run::T* t = f(){() →* self::run::T*};
+  core::print("done running");
+  return t;
+}
+static method printRunning() → void {
+  core::print("running");
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::printRunning
+}
diff --git a/pkg/front_end/testcases/inference_new/while_loop.dart.weak.modular.expect b/pkg/front_end/testcases/inference_new/while_loop.dart.weak.modular.expect
new file mode 100644
index 0000000..7469e19
--- /dev/null
+++ b/pkg/front_end/testcases/inference_new/while_loop.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method f<T extends core::Object* = dynamic>() → self::f::T*
+  return null;
+static method test() → void {
+  while (self::f<core::bool*>()) {
+    core::int* x = 0;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/all_steps.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/all_steps.dart.weak.modular.expect
new file mode 100644
index 0000000..336e446
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/all_steps.dart.weak.modular.expect
@@ -0,0 +1,52 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class B<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::X*, self::B::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::X*, self::C::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<X extends self::B<self::D::X*, self::D::Y*>* = self::B<dynamic, dynamic>*, Y extends self::C<self::D::X*, self::D::Y*>* = self::C<dynamic, dynamic>*, Z extends (self::D::Y*) →* self::D::X* = (Null) →* self::B<dynamic, dynamic>*, W extends core::num*> extends core::Object {
+  synthetic constructor •() → self::D<self::D::X*, self::D::Y*, self::D::Z*, self::D::W*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::D<self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*, (Null) →* self::B<dynamic, dynamic>*, core::num*>* d;
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/body_generic_classes_from_dill.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/body_generic_classes_from_dill.dart.weak.modular.expect
new file mode 100644
index 0000000..7de5b6d
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/body_generic_classes_from_dill.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+import "dart:collection";
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic {
+    col::LinkedListEntry<col::LinkedListEntry<dynamic>>* bar;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  col::LinkedListEntry<col::LinkedListEntry<dynamic>>* bar;
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/body_literal_list.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/body_literal_list.dart.weak.modular.expect
new file mode 100644
index 0000000..ff8c02f
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/body_literal_list.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::num*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic {
+    core::List<self::A<core::num*>*>* a = <self::A<core::num*>*>[];
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::List<self::A<core::num*>*>* a = <self::A<core::num*>*>[];
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/body_literal_list_with_generic_argument.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/body_literal_list_with_generic_argument.dart.weak.modular.expect
new file mode 100644
index 0000000..186472b
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/body_literal_list_with_generic_argument.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<U extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::U*>*
+    : super core::Object::•()
+    ;
+  method fun() → dynamic {
+    core::List<self::A<self::B::U*>*>* foo = <self::A<self::B::U*>*>[];
+    core::List<self::A<core::num*>*>* bar = <self::A<core::num*>*>[];
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/body_literal_map.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/body_literal_map.dart.weak.modular.expect
new file mode 100644
index 0000000..28c2e96
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/body_literal_map.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::num*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic {
+    core::Map<self::A<core::num*>*, self::A<core::num*>*>* a = <self::A<core::num*>*, self::A<core::num*>*>{};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::Map<self::A<core::num*>*, self::A<core::num*>*>* a = <self::A<core::num*>*, self::A<core::num*>*>{};
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/body_omitted_bound.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/body_omitted_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..5aa8724
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/body_omitted_bound.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+import "dart:collection";
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method fun() → dynamic {
+    self::A<dynamic>* a;
+    col::DoubleLinkedQueue<dynamic>* c;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::A<dynamic>* a;
+  col::DoubleLinkedQueue<dynamic>* c;
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/body_super_bounded_type.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/body_super_bounded_type.dart.weak.modular.expect
new file mode 100644
index 0000000..9b5f2f8
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/body_super_bounded_type.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends self::A<self::A::T*>* = self::A<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic {
+    self::A<self::A<dynamic>*>* a;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::A<self::A<dynamic>*>* a;
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/body_typedef_literal_list.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/body_typedef_literal_list.dart.weak.modular.expect
new file mode 100644
index 0000000..19c0496
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/body_typedef_literal_list.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef A<contravariant T extends core::num*> = (T*) →* dynamic;
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic {
+    core::List<(core::num*) →* dynamic>* a = <(core::num*) →* dynamic>[];
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::List<(core::num*) →* dynamic>* a = <(core::num*) →* dynamic>[];
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/body_typedef_literal_list_with_generic_argument.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/body_typedef_literal_list_with_generic_argument.dart.weak.modular.expect
new file mode 100644
index 0000000..cf2c35d
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/body_typedef_literal_list_with_generic_argument.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef A<contravariant T extends core::Object* = dynamic> = (T*) →* dynamic;
+class B<U extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::U*>*
+    : super core::Object::•()
+    ;
+  method fun() → dynamic {
+    core::List<(self::B::U*) →* dynamic>* foo = <(self::B::U*) →* dynamic>[];
+    core::List<(core::num*) →* dynamic>* bar = <(core::num*) →* dynamic>[];
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::List<(core::num*) →* dynamic>* bar = <(core::num*) →* dynamic>[];
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/body_typedef_literal_map.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/body_typedef_literal_map.dart.weak.modular.expect
new file mode 100644
index 0000000..82bfe94
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/body_typedef_literal_map.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef A<contravariant T extends core::num*> = (T*) →* dynamic;
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic {
+    core::Map<(core::num*) →* dynamic, (core::num*) →* dynamic>* a = <(core::num*) →* dynamic, (core::num*) →* dynamic>{};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::Map<(core::num*) →* dynamic, (core::num*) →* dynamic>* a = <(core::num*) →* dynamic, (core::num*) →* dynamic>{};
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/body_typedef_omitted_bound.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/body_typedef_omitted_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..f6435f7
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/body_typedef_omitted_bound.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef A<contravariant T extends core::Object* = dynamic> = (T*) →* dynamic;
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic {
+    (dynamic) →* dynamic a;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  (dynamic) →* dynamic a;
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/body_typedef_super_bounded_type.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/body_typedef_super_bounded_type.dart.weak.modular.expect
new file mode 100644
index 0000000..d4a97aa
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/body_typedef_super_bounded_type.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef A<contravariant T extends core::Object* = dynamic> = (T*) →* dynamic;
+typedef B<contravariant U extends (U*) →* dynamic = (dynamic) →* dynamic> = (U*) →* dynamic;
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic {
+    ((dynamic) →* dynamic) →* dynamic b;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  ((dynamic) →* dynamic) →* dynamic b;
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/contravariant_dependence.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/contravariant_dependence.dart.weak.modular.expect
new file mode 100644
index 0000000..98dbd20
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/contravariant_dependence.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class C<X extends core::num*, Y extends (self::C::X*) →* void = (Null) →* void> extends core::Object {
+  synthetic constructor •() → self::C<self::C::X*, self::C::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C<core::num*, (Null) →* void>* c;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/contravariant_dependence_in_literals.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/contravariant_dependence_in_literals.dart.weak.modular.expect
new file mode 100644
index 0000000..a7c105a
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/contravariant_dependence_in_literals.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class C<X extends core::num*, Y extends (self::C::X*) →* void = (Null) →* void> extends core::Object {
+  synthetic constructor •() → self::C<self::C::X*, self::C::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::List<self::C<core::num*, (Null) →* void>*>* lc = <self::C<core::num*, (Null) →* void>*>[];
+static field core::Map<self::C<core::num*, (Null) →* void>*, self::C<core::num*, (Null) →* void>*>* mc = <self::C<core::num*, (Null) →* void>*, self::C<core::num*, (Null) →* void>*>{};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/contravariant_mutual_dependence.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/contravariant_mutual_dependence.dart.weak.modular.expect
new file mode 100644
index 0000000..e4ecd94
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/contravariant_mutual_dependence.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class D<X extends (self::D::X*, self::D::Y*) →* void = (Null, Null) →* void, Y extends (self::D::X*, self::D::Y*) →* void = (Null, Null) →* void> extends core::Object {
+  synthetic constructor •() → self::D<self::D::X*, self::D::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E<X extends (self::E::X*) →* void = (Null) →* void> extends core::Object {
+  synthetic constructor •() → self::E<self::E::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::D<(Null, Null) →* void, (Null, Null) →* void>* d;
+static field self::E<(Null) →* void>* e;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/contravariant_mutual_dependence_in_literals.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/contravariant_mutual_dependence_in_literals.dart.weak.modular.expect
new file mode 100644
index 0000000..eaaf4d5
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/contravariant_mutual_dependence_in_literals.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class D<X extends (self::D::X*, self::D::Y*) →* void = (Null, Null) →* void, Y extends (self::D::X*, self::D::Y*) →* void = (Null, Null) →* void> extends core::Object {
+  synthetic constructor •() → self::D<self::D::X*, self::D::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E<X extends (self::E::X*) →* void = (Null) →* void> extends core::Object {
+  synthetic constructor •() → self::E<self::E::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::List<self::D<(Null, Null) →* void, (Null, Null) →* void>*>* ld = <self::D<(Null, Null) →* void, (Null, Null) →* void>*>[];
+static field core::Map<self::D<(Null, Null) →* void, (Null, Null) →* void>*, self::D<(Null, Null) →* void, (Null, Null) →* void>*>* md = <self::D<(Null, Null) →* void, (Null, Null) →* void>*, self::D<(Null, Null) →* void, (Null, Null) →* void>*>{};
+static field core::List<self::E<(Null) →* void>*>* le = <self::E<(Null) →* void>*>[];
+static field core::Map<self::E<(Null) →* void>*, self::E<(Null) →* void>*>* me = <self::E<(Null) →* void>*, self::E<(Null) →* void>*>{};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/covariant_dependence.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/covariant_dependence.dart.weak.modular.expect
new file mode 100644
index 0000000..5fa1f9e
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/covariant_dependence.dart.weak.modular.expect
@@ -0,0 +1,84 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<X extends core::Object* = dynamic, Y extends self::A<self::C::X*>* = self::A<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::C<self::C::X*, self::C::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<X extends core::num*, Y extends self::A<self::D::X*>* = self::A<core::num*>*> extends core::Object {
+  synthetic constructor •() → self::D<self::D::X*, self::D::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E<X extends core::Object* = dynamic, Y extends () →* self::E::X* = () →* dynamic> extends core::Object {
+  synthetic constructor •() → self::E<self::E::X*, self::E::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F<X extends core::num*, Y extends () →* self::F::X* = () →* core::num*> extends core::Object {
+  synthetic constructor •() → self::F<self::F::X*, self::F::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C<dynamic, self::A<dynamic>*>* c;
+static field self::D<core::num*, self::A<core::num*>*>* d;
+static field self::E<dynamic, () →* dynamic>* e;
+static field self::F<core::num*, () →* core::num*>* f;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/covariant_dependence_in_literals.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/covariant_dependence_in_literals.dart.weak.modular.expect
new file mode 100644
index 0000000..6957306
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/covariant_dependence_in_literals.dart.weak.modular.expect
@@ -0,0 +1,88 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<X extends core::Object* = dynamic, Y extends self::A<self::C::X*>* = self::A<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::C<self::C::X*, self::C::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<X extends core::num*, Y extends self::A<self::D::X*>* = self::A<core::num*>*> extends core::Object {
+  synthetic constructor •() → self::D<self::D::X*, self::D::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E<X extends core::Object* = dynamic, Y extends () →* self::E::X* = () →* dynamic> extends core::Object {
+  synthetic constructor •() → self::E<self::E::X*, self::E::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F<X extends core::num*, Y extends () →* self::F::X* = () →* core::num*> extends core::Object {
+  synthetic constructor •() → self::F<self::F::X*, self::F::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::List<self::C<dynamic, self::A<dynamic>*>*>* lc = <self::C<dynamic, self::A<dynamic>*>*>[];
+static field core::Map<self::C<dynamic, self::A<dynamic>*>*, self::C<dynamic, self::A<dynamic>*>*>* mc = <self::C<dynamic, self::A<dynamic>*>*, self::C<dynamic, self::A<dynamic>*>*>{};
+static field core::List<self::D<core::num*, self::A<core::num*>*>*>* ld = <self::D<core::num*, self::A<core::num*>*>*>[];
+static field core::Map<self::D<core::num*, self::A<core::num*>*>*, self::D<core::num*, self::A<core::num*>*>*>* md = <self::D<core::num*, self::A<core::num*>*>*, self::D<core::num*, self::A<core::num*>*>*>{};
+static field core::List<self::E<dynamic, () →* dynamic>*>* le = <self::E<dynamic, () →* dynamic>*>[];
+static field core::Map<self::E<dynamic, () →* dynamic>*, self::E<dynamic, () →* dynamic>*>* me = <self::E<dynamic, () →* dynamic>*, self::E<dynamic, () →* dynamic>*>{};
+static field core::List<self::F<core::num*, () →* core::num*>*>* lf = <self::F<core::num*, () →* core::num*>*>[];
+static field core::Map<self::F<core::num*, () →* core::num*>*, self::F<core::num*, () →* core::num*>*>* mf = <self::F<core::num*, () →* core::num*>*, self::F<core::num*, () →* core::num*>*>{};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/covariant_mutual_dependence.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/covariant_mutual_dependence.dart.weak.modular.expect
new file mode 100644
index 0000000..e5e5db0
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/covariant_mutual_dependence.dart.weak.modular.expect
@@ -0,0 +1,83 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class B<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::X*, self::B::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::X*, self::C::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<X extends self::B<self::D::X*, self::D::Y*>* = self::B<dynamic, dynamic>*, Y extends self::C<self::D::X*, self::D::Y*>* = self::C<dynamic, dynamic>*> extends core::Object {
+  synthetic constructor •() → self::D<self::D::X*, self::D::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E<X extends self::B<self::E::X*, self::E::Y*>* = self::B<dynamic, dynamic>*, Y extends () →* self::E::X* = () →* dynamic> extends core::Object {
+  synthetic constructor •() → self::E<self::E::X*, self::E::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F<X extends () →* self::F::X* = () →* dynamic> extends core::Object {
+  synthetic constructor •() → self::F<self::F::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::D<self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*>* d;
+static field self::E<self::B<dynamic, dynamic>*, () →* dynamic>* e;
+static field self::F<() →* dynamic>* f;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/covariant_mutual_dependence_in_literals.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/covariant_mutual_dependence_in_literals.dart.weak.modular.expect
new file mode 100644
index 0000000..b532365
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/covariant_mutual_dependence_in_literals.dart.weak.modular.expect
@@ -0,0 +1,86 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class B<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::X*, self::B::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::X*, self::C::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<X extends self::B<self::D::X*, self::D::Y*>* = self::B<dynamic, dynamic>*, Y extends self::C<self::D::X*, self::D::Y*>* = self::C<dynamic, dynamic>*> extends core::Object {
+  synthetic constructor •() → self::D<self::D::X*, self::D::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E<X extends self::B<self::E::X*, self::E::Y*>* = self::B<dynamic, dynamic>*, Y extends () →* self::E::X* = () →* dynamic> extends core::Object {
+  synthetic constructor •() → self::E<self::E::X*, self::E::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F<X extends () →* self::F::X* = () →* dynamic> extends core::Object {
+  synthetic constructor •() → self::F<self::F::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::List<self::D<self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*>*>* ld = <self::D<self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*>*>[];
+static field core::Map<self::D<self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*>*, self::D<self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*>*>* md = <self::D<self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*>*, self::D<self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*>*>{};
+static field core::List<self::E<self::B<dynamic, dynamic>*, () →* dynamic>*>* le = <self::E<self::B<dynamic, dynamic>*, () →* dynamic>*>[];
+static field core::Map<self::E<self::B<dynamic, dynamic>*, () →* dynamic>*, self::E<self::B<dynamic, dynamic>*, () →* dynamic>*>* me = <self::E<self::B<dynamic, dynamic>*, () →* dynamic>*, self::E<self::B<dynamic, dynamic>*, () →* dynamic>*>{};
+static field core::List<self::F<() →* dynamic>*>* lf = <self::F<() →* dynamic>*>[];
+static field core::Map<self::F<() →* dynamic>*, self::F<() →* dynamic>*>* mf = <self::F<() →* dynamic>*, self::F<() →* dynamic>*>{};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/dependence.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/dependence.dart.weak.modular.expect
new file mode 100644
index 0000000..e5f74ce
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/dependence.dart.weak.modular.expect
@@ -0,0 +1,52 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<X extends core::Object* = dynamic, Y extends (self::C::X*) →* self::C::X* = (Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::X*, self::C::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<X extends core::num*, Y extends (self::D::X*) →* self::D::X* = (Null) →* core::num*> extends core::Object {
+  synthetic constructor •() → self::D<self::D::X*, self::D::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C<dynamic, (Null) →* dynamic>* c;
+static field self::D<core::num*, (Null) →* core::num*>* d;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/dependence_in_literals.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/dependence_in_literals.dart.weak.modular.expect
new file mode 100644
index 0000000..2cf489e
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/dependence_in_literals.dart.weak.modular.expect
@@ -0,0 +1,54 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<X extends core::Object* = dynamic, Y extends (self::C::X*) →* self::C::X* = (Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::X*, self::C::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<X extends core::num*, Y extends (self::D::X*) →* self::D::X* = (Null) →* core::num*> extends core::Object {
+  synthetic constructor •() → self::D<self::D::X*, self::D::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::List<self::C<dynamic, (Null) →* dynamic>*>* lc = <self::C<dynamic, (Null) →* dynamic>*>[];
+static field core::Map<self::C<dynamic, (Null) →* dynamic>*, self::C<dynamic, (Null) →* dynamic>*>* mc = <self::C<dynamic, (Null) →* dynamic>*, self::C<dynamic, (Null) →* dynamic>*>{};
+static field core::List<self::D<core::num*, (Null) →* core::num*>*>* ld = <self::D<core::num*, (Null) →* core::num*>*>[];
+static field core::Map<self::D<core::num*, (Null) →* core::num*>*, self::D<core::num*, (Null) →* core::num*>*>* md = <self::D<core::num*, (Null) →* core::num*>*, self::D<core::num*, (Null) →* core::num*>*>{};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/generic_classes_from_dill.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/generic_classes_from_dill.dart.weak.modular.expect
new file mode 100644
index 0000000..175fa49
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/generic_classes_from_dill.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library;
+import self as self;
+import "dart:collection" as col;
+
+import "dart:collection";
+
+static field col::LinkedListEntry<col::LinkedListEntry<dynamic>>* y;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/inference_constrained_by_bound.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/inference_constrained_by_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..5da171e
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/inference_constrained_by_bound.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::num*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::A<core::num*>* a = new self::A::•<core::num*>();
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/inference_defaults_to_bound.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/inference_defaults_to_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..13d0abf
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/inference_defaults_to_bound.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::num*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::A::•<core::num*>();
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/inference_gives_input.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/inference_gives_input.dart.weak.modular.expect
new file mode 100644
index 0000000..f971b81
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/inference_gives_input.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::num*, S extends core::List<self::B::T*>* = core::List<core::num*>*> extends self::A<self::B::T*> {
+  constructor •([self::B::T* x = #C1]) → self::B<self::B::T*, self::B::S*>*
+    : super self::A::•() {}
+}
+static method main() → dynamic {
+  self::B<core::num*, core::List<core::num*>*>* x;
+  self::B<core::int*, core::List<core::int*>*>* y = new self::B::•<core::int*, core::List<core::int*>*>(3);
+  self::A<core::int*>* z = new self::B::•<core::int*, core::List<core::int*>*>();
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/inference_super_bounded_rejected.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/inference_super_bounded_rejected.dart.weak.modular.expect
new file mode 100644
index 0000000..7c188466
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/inference_super_bounded_rejected.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/inference_super_bounded_rejected.dart:11:13: Error: Inferred type argument 'Comparable<dynamic>' doesn't conform to the bound 'Comparable<T>' of the type variable 'T' on 'B'.
+//  - 'Comparable' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// var y = new B();
+//             ^
+// pkg/front_end/testcases/instantiate_to_bound/inference_super_bounded_rejected.dart:9:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<T extends Comparable<T>> {}
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class B<T extends core::Comparable<self::B::T*>* = core::Comparable<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::B<core::Comparable<dynamic>*>* y = new self::B::•<core::Comparable<dynamic>*>();
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/instantiated_in_outline.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/instantiated_in_outline.dart.weak.modular.expect
new file mode 100644
index 0000000..e04675b
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/instantiated_in_outline.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::num*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method foo(self::A<core::num*>* a) → dynamic
+    return null;
+  method bar() → self::A<core::num*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/literal_list.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/literal_list.dart.weak.modular.expect
new file mode 100644
index 0000000..f1af679
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/literal_list.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::num*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::List<self::A<core::num*>*>* a = <self::A<core::num*>*>[];
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/literal_list_with_generic_argument.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/literal_list_with_generic_argument.dart.weak.modular.expect
new file mode 100644
index 0000000..a42b37a
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/literal_list_with_generic_argument.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<S extends core::Object* = dynamic> extends core::Object {
+  final field core::List<self::A<self::B::S*>*>* foo = <self::A<self::B::S*>*>[];
+  final field core::List<self::A<core::num*>*>* bar = <self::A<core::num*>*>[];
+  synthetic constructor •() → self::B<self::B::S*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/literal_map.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/literal_map.dart.weak.modular.expect
new file mode 100644
index 0000000..e2fc6ab
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/literal_map.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::num*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::Map<self::A<core::num*>*, self::A<core::num*>*>* a = <self::A<core::num*>*, self::A<core::num*>*>{};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/multiple_strongly_connected.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/multiple_strongly_connected.dart.weak.modular.expect
new file mode 100644
index 0000000..1576c98
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/multiple_strongly_connected.dart.weak.modular.expect
@@ -0,0 +1,170 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/multiple_strongly_connected.dart:41:9: Error: Type 'T' is a bound of itself via 'U', 'Y', 'Z'.
+// Try breaking the cycle by removing at least on of the 'extends' clauses in the cycle.
+// class I<T extends U, U extends Y, V extends Function(W), W extends Function(X),
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::X*, self::B::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::X*, self::C::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<X extends self::A<self::D::X*>* = self::A<dynamic>*, Y extends self::A<self::D::Y*>* = self::A<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::D<self::D::X*, self::D::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E<W extends self::B<self::E::W*, self::E::X*>* = self::B<dynamic, dynamic>*, X extends self::C<self::E::W*, self::E::X*>* = self::C<dynamic, dynamic>*, Y extends self::B<self::E::Y*, self::E::Z*>* = self::B<dynamic, dynamic>*, Z extends self::C<self::E::Y*, self::E::Z*>* = self::C<dynamic, dynamic>*> extends core::Object {
+  synthetic constructor •() → self::E<self::E::W*, self::E::X*, self::E::Y*, self::E::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F<V extends core::num*, W extends self::B<self::F::W*, self::F::X*>* = self::B<dynamic, dynamic>*, X extends self::C<self::F::W*, self::F::X*>* = self::C<dynamic, dynamic>*, Y extends self::B<self::F::W*, self::F::X*>* = self::B<self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*>*, Z extends self::C<self::F::Y*, self::F::Z*>* = self::C<self::B<self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*>*, dynamic>*> extends core::Object {
+  synthetic constructor •() → self::F<self::F::V*, self::F::W*, self::F::X*, self::F::Y*, self::F::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class G<V extends core::num*, W extends self::B<self::G::V*, self::G::X*>* = self::B<core::num*, dynamic>*, X extends self::C<self::G::W*, self::G::V*>* = self::C<dynamic, core::num*>*, Y extends self::B<self::G::W*, self::G::X*>* = self::B<self::B<core::num*, dynamic>*, self::C<dynamic, core::num*>*>*, Z extends self::C<self::G::Y*, self::G::Z*>* = self::C<self::B<self::B<core::num*, dynamic>*, self::C<dynamic, core::num*>*>*, dynamic>*> extends core::Object {
+  synthetic constructor •() → self::G<self::G::V*, self::G::W*, self::G::X*, self::G::Y*, self::G::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class H<S extends self::A<self::H::S*>* = self::A<dynamic>*, T extends self::B<self::H::T*, self::H::U*>* = self::B<dynamic, dynamic>*, U extends self::C<self::H::T*, self::H::U*>* = self::C<dynamic, dynamic>*, V extends self::A<self::H::V*>* = self::A<dynamic>*, W extends self::H::S* = self::A<dynamic>*, X extends self::H::T* = self::B<dynamic, dynamic>*, Y extends self::H::U* = self::C<dynamic, dynamic>*, Z extends self::H::V* = self::A<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::H<self::H::S*, self::H::T*, self::H::U*, self::H::V*, self::H::W*, self::H::X*, self::H::Y*, self::H::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class I<T extends invalid-type, U extends self::I::Y* = invalid-type, V extends (self::I::W*) →* dynamic = (Null) →* dynamic, W extends (self::I::X*) →* dynamic = (Null) →* dynamic, X extends (self::I::V*) →* dynamic = (Null) →* dynamic, Y extends self::I::Z* = invalid-type, Z extends self::I::T* = invalid-type> extends core::Object {
+  synthetic constructor •() → self::I<self::I::T*, self::I::U*, self::I::V*, self::I::W*, self::I::X*, self::I::Y*, self::I::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class J<S extends (self::J::U*) →* self::J::T* = (Null) →* dynamic, T extends (self::J::S*) →* self::J::U* = (Null) →* dynamic, U extends (self::J::T*) →* self::J::S* = (Null) →* dynamic, V extends self::J::W* = dynamic, W extends self::J::X* = dynamic, X extends (self::J::V*) →* self::J::Y* = (Null) →* dynamic, Y extends self::J::Z* = dynamic, Z extends self::J::X* = dynamic> extends core::Object {
+  synthetic constructor •() → self::J<self::J::S*, self::J::T*, self::J::U*, self::J::V*, self::J::W*, self::J::X*, self::J::Y*, self::J::Z*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::D<self::A<dynamic>*, self::A<dynamic>*>* d;
+static field self::E<self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*, self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*>* e;
+static field self::F<core::num*, self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*, self::B<self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*>*, self::C<self::B<self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*>*, dynamic>*>* f;
+static field self::G<core::num*, self::B<core::num*, dynamic>*, self::C<dynamic, core::num*>*, self::B<self::B<core::num*, dynamic>*, self::C<dynamic, core::num*>*>*, self::C<self::B<self::B<core::num*, dynamic>*, self::C<dynamic, core::num*>*>*, dynamic>*>* g;
+static field self::H<self::A<dynamic>*, self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*, self::A<dynamic>*, self::A<dynamic>*, self::B<dynamic, dynamic>*, self::C<dynamic, dynamic>*, self::A<dynamic>*>* h;
+static field self::I<invalid-type, invalid-type, (Null) →* dynamic, (Null) →* dynamic, (Null) →* dynamic, invalid-type, invalid-type>* i;
+static field self::J<(Null) →* dynamic, (Null) →* dynamic, (Null) →* dynamic, dynamic, dynamic, (Null) →* dynamic, dynamic, dynamic>* j;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/mutual_dependence.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/mutual_dependence.dart.weak.modular.expect
new file mode 100644
index 0000000..381fd70
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/mutual_dependence.dart.weak.modular.expect
@@ -0,0 +1,164 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class B<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::X*, self::B::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C1<X extends (self::C1::Y*) →* self::C1::X* = (Null) →* dynamic, Y extends (self::C1::Y*) →* self::C1::X* = (Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::C1<self::C1::X*, self::C1::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C2<X extends (self::C2::Y*) →* self::C2::X* = (Null) →* dynamic, Y extends (self::C2::X*) →* self::C2::Y* = (Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::C2<self::C2::X*, self::C2::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C3<X extends (self::C3::X*, self::C3::Y*) →* self::C3::X* = (Null, Null) →* dynamic, Y extends (self::C3::X*, self::C3::Y*) →* self::C3::X* = (Null, Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::C3<self::C3::X*, self::C3::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C4<X extends (self::C4::X*, self::C4::Y*) →* self::C4::X* = (Null, Null) →* dynamic, Y extends (self::C4::X*, self::C4::Y*) →* self::C4::Y* = (Null, Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::C4<self::C4::X*, self::C4::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D1<X extends self::B<self::D1::X*, self::D1::Y*>* = self::B<dynamic, dynamic>*, Y extends (self::D1::Y*) →* self::D1::X* = (Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::D1<self::D1::X*, self::D1::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D2<X extends self::B<self::D2::X*, self::D2::Y*>* = self::B<dynamic, dynamic>*, Y extends (self::D2::X*) →* self::D2::Y* = (Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::D2<self::D2::X*, self::D2::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D3<X extends self::B<self::D3::X*, self::D3::Y*>* = self::B<dynamic, dynamic>*, Y extends (self::D3::X*, self::D3::Y*) →* self::D3::X* = (Null, Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::D3<self::D3::X*, self::D3::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D4<X extends self::B<self::D4::X*, self::D4::Y*>* = self::B<dynamic, dynamic>*, Y extends (self::D4::X*, self::D4::Y*) →* self::D4::Y* = (Null, Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::D4<self::D4::X*, self::D4::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E<X extends (self::E::X*) →* self::E::X* = (Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::E<self::E::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C1<(Null) →* dynamic, (Null) →* dynamic>* c1;
+static field self::C2<(Null) →* dynamic, (Null) →* dynamic>* c2;
+static field self::C3<(Null, Null) →* dynamic, (Null, Null) →* dynamic>* c3;
+static field self::C4<(Null, Null) →* dynamic, (Null, Null) →* dynamic>* c4;
+static field self::D1<self::B<dynamic, dynamic>*, (Null) →* dynamic>* d1;
+static field self::D2<self::B<dynamic, dynamic>*, (Null) →* dynamic>* d2;
+static field self::D3<self::B<dynamic, dynamic>*, (Null, Null) →* dynamic>* d3;
+static field self::D4<self::B<dynamic, dynamic>*, (Null, Null) →* dynamic>* d4;
+static field self::E<(Null) →* dynamic>* e;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/mutual_dependence_in_literals.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/mutual_dependence_in_literals.dart.weak.modular.expect
new file mode 100644
index 0000000..57e2111
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/mutual_dependence_in_literals.dart.weak.modular.expect
@@ -0,0 +1,173 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class B<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::X*, self::B::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C1<X extends (self::C1::Y*) →* self::C1::X* = (Null) →* dynamic, Y extends (self::C1::Y*) →* self::C1::X* = (Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::C1<self::C1::X*, self::C1::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C2<X extends (self::C2::Y*) →* self::C2::X* = (Null) →* dynamic, Y extends (self::C2::X*) →* self::C2::Y* = (Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::C2<self::C2::X*, self::C2::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C3<X extends (self::C3::X*, self::C3::Y*) →* self::C3::X* = (Null, Null) →* dynamic, Y extends (self::C3::X*, self::C3::Y*) →* self::C3::X* = (Null, Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::C3<self::C3::X*, self::C3::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C4<X extends (self::C4::X*, self::C4::Y*) →* self::C4::X* = (Null, Null) →* dynamic, Y extends (self::C4::X*, self::C4::Y*) →* self::C4::Y* = (Null, Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::C4<self::C4::X*, self::C4::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D1<X extends self::B<self::D1::X*, self::D1::Y*>* = self::B<dynamic, dynamic>*, Y extends (self::D1::Y*) →* self::D1::X* = (Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::D1<self::D1::X*, self::D1::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D2<X extends self::B<self::D2::X*, self::D2::Y*>* = self::B<dynamic, dynamic>*, Y extends (self::D2::X*) →* self::D2::Y* = (Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::D2<self::D2::X*, self::D2::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D3<X extends self::B<self::D3::X*, self::D3::Y*>* = self::B<dynamic, dynamic>*, Y extends (self::D3::X*, self::D3::Y*) →* self::D3::X* = (Null, Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::D3<self::D3::X*, self::D3::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D4<X extends self::B<self::D4::X*, self::D4::Y*>* = self::B<dynamic, dynamic>*, Y extends (self::D4::X*, self::D4::Y*) →* self::D4::Y* = (Null, Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::D4<self::D4::X*, self::D4::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E<X extends (self::E::X*) →* self::E::X* = (Null) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::E<self::E::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::List<self::C1<(Null) →* dynamic, (Null) →* dynamic>*>* lc1 = <self::C1<(Null) →* dynamic, (Null) →* dynamic>*>[];
+static field core::Map<self::C1<(Null) →* dynamic, (Null) →* dynamic>*, self::C1<(Null) →* dynamic, (Null) →* dynamic>*>* mc1 = <self::C1<(Null) →* dynamic, (Null) →* dynamic>*, self::C1<(Null) →* dynamic, (Null) →* dynamic>*>{};
+static field core::List<self::C2<(Null) →* dynamic, (Null) →* dynamic>*>* lc2 = <self::C2<(Null) →* dynamic, (Null) →* dynamic>*>[];
+static field core::Map<self::C2<(Null) →* dynamic, (Null) →* dynamic>*, self::C2<(Null) →* dynamic, (Null) →* dynamic>*>* mc2 = <self::C2<(Null) →* dynamic, (Null) →* dynamic>*, self::C2<(Null) →* dynamic, (Null) →* dynamic>*>{};
+static field core::List<self::C3<(Null, Null) →* dynamic, (Null, Null) →* dynamic>*>* lc3 = <self::C3<(Null, Null) →* dynamic, (Null, Null) →* dynamic>*>[];
+static field core::Map<self::C3<(Null, Null) →* dynamic, (Null, Null) →* dynamic>*, self::C3<(Null, Null) →* dynamic, (Null, Null) →* dynamic>*>* mc3 = <self::C3<(Null, Null) →* dynamic, (Null, Null) →* dynamic>*, self::C3<(Null, Null) →* dynamic, (Null, Null) →* dynamic>*>{};
+static field core::List<self::C4<(Null, Null) →* dynamic, (Null, Null) →* dynamic>*>* lc4 = <self::C4<(Null, Null) →* dynamic, (Null, Null) →* dynamic>*>[];
+static field core::Map<self::C4<(Null, Null) →* dynamic, (Null, Null) →* dynamic>*, self::C4<(Null, Null) →* dynamic, (Null, Null) →* dynamic>*>* mc4 = <self::C4<(Null, Null) →* dynamic, (Null, Null) →* dynamic>*, self::C4<(Null, Null) →* dynamic, (Null, Null) →* dynamic>*>{};
+static field core::List<self::D1<self::B<dynamic, dynamic>*, (Null) →* dynamic>*>* ld1 = <self::D1<self::B<dynamic, dynamic>*, (Null) →* dynamic>*>[];
+static field core::Map<self::D1<self::B<dynamic, dynamic>*, (Null) →* dynamic>*, self::D1<self::B<dynamic, dynamic>*, (Null) →* dynamic>*>* md1 = <self::D1<self::B<dynamic, dynamic>*, (Null) →* dynamic>*, self::D1<self::B<dynamic, dynamic>*, (Null) →* dynamic>*>{};
+static field core::List<self::D2<self::B<dynamic, dynamic>*, (Null) →* dynamic>*>* ld2 = <self::D2<self::B<dynamic, dynamic>*, (Null) →* dynamic>*>[];
+static field core::Map<self::D2<self::B<dynamic, dynamic>*, (Null) →* dynamic>*, self::D2<self::B<dynamic, dynamic>*, (Null) →* dynamic>*>* md2 = <self::D2<self::B<dynamic, dynamic>*, (Null) →* dynamic>*, self::D2<self::B<dynamic, dynamic>*, (Null) →* dynamic>*>{};
+static field core::List<self::D3<self::B<dynamic, dynamic>*, (Null, Null) →* dynamic>*>* ld3 = <self::D3<self::B<dynamic, dynamic>*, (Null, Null) →* dynamic>*>[];
+static field core::Map<self::D3<self::B<dynamic, dynamic>*, (Null, Null) →* dynamic>*, self::D3<self::B<dynamic, dynamic>*, (Null, Null) →* dynamic>*>* md3 = <self::D3<self::B<dynamic, dynamic>*, (Null, Null) →* dynamic>*, self::D3<self::B<dynamic, dynamic>*, (Null, Null) →* dynamic>*>{};
+static field core::List<self::D4<self::B<dynamic, dynamic>*, (Null, Null) →* dynamic>*>* ld4 = <self::D4<self::B<dynamic, dynamic>*, (Null, Null) →* dynamic>*>[];
+static field core::Map<self::D4<self::B<dynamic, dynamic>*, (Null, Null) →* dynamic>*, self::D4<self::B<dynamic, dynamic>*, (Null, Null) →* dynamic>*>* md4 = <self::D4<self::B<dynamic, dynamic>*, (Null, Null) →* dynamic>*, self::D4<self::B<dynamic, dynamic>*, (Null, Null) →* dynamic>*>{};
+static field core::List<self::E<(Null) →* dynamic>*>* le = <self::E<(Null) →* dynamic>*>[];
+static field core::Map<self::E<(Null) →* dynamic>*, self::E<(Null) →* dynamic>*>* me = <self::E<(Null) →* dynamic>*, self::E<(Null) →* dynamic>*>{};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_bound_due_to_non_simple.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_bound_due_to_non_simple.dart.weak.modular.expect
new file mode 100644
index 0000000..c15ea34
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_bound_due_to_non_simple.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_bound_due_to_non_simple.dart:12:9: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+// class B<TypeU extends A> {}
+//         ^^^^^
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_bound_due_to_non_simple.dart:10:16: Context: Bound of this variable references variable 'TypeT' from the same declaration.
+// class A<TypeT, TypeS extends TypeT> {}
+//                ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<TypeT extends core::Object* = dynamic, TypeS extends self::A::TypeT* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::TypeT*, self::A::TypeS*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<TypeU extends self::A<dynamic, dynamic>* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::TypeU*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<TypeV extends self::B<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::C<self::C::TypeV*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::C<self::B<dynamic>*>* c;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_bound_due_to_variables.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_bound_due_to_variables.dart.weak.modular.expect
new file mode 100644
index 0000000..a052bc5
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_bound_due_to_variables.dart.weak.modular.expect
@@ -0,0 +1,47 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_bound_due_to_variables.dart:11:9: Error: Generic type 'A' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'A' here.
+// class B<TypeU extends A> {}
+//         ^^^^^
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_bound_due_to_variables.dart:9:16: Context: Bound of this variable references variable 'TypeT' from the same declaration.
+// class A<TypeT, TypeS extends TypeT> {}
+//                ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<TypeT extends core::Object* = dynamic, TypeS extends self::A::TypeT* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::TypeT*, self::A::TypeS*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<TypeU extends self::A<dynamic, dynamic>* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::TypeU*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::B<dynamic>* b;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_class_parametrized_typedef_cycle.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_class_parametrized_typedef_cycle.dart.weak.modular.expect
new file mode 100644
index 0000000..a8be06f
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_class_parametrized_typedef_cycle.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_class_parametrized_typedef_cycle.dart:9:12: Error: Type variables can't have generic function types in their bounds.
+// class Hest<TypeX extends Fisk> {}
+//            ^^^^^
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_class_parametrized_typedef_cycle.dart:11:9: Error: Generic type 'Fisk' can't be used without type arguments in the bounds of its own type variables. It is referenced indirectly through 'Hest'.
+// Try providing type arguments to 'Hest' here or to some other raw types in the bounds along the reference chain.
+// typedef Fisk = void Function<TypeY extends Hest>();
+//         ^^^^
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_class_parametrized_typedef_cycle.dart:11:30: Context: Bound of this variable references raw type 'Hest'.
+// typedef Fisk = void Function<TypeY extends Hest>();
+//                              ^^^^^
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_class_parametrized_typedef_cycle.dart:9:12: Context: Bound of this variable references raw type 'Fisk'.
+// class Hest<TypeX extends Fisk> {}
+//            ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef Fisk = <TypeY extends core::Object* = dynamic>() →* void;
+class Hest<TypeX extends <TypeY extends core::Object* = dynamic>() →* void = dynamic> extends core::Object {
+  synthetic constructor •() → self::Hest<self::Hest::TypeX*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_class_typedef_cycle.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_class_typedef_cycle.dart.weak.modular.expect
new file mode 100644
index 0000000..1adc8bcb
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_class_typedef_cycle.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_class_typedef_cycle.dart:10:14: Error: Generic type 'Fisk' can't be used without type arguments in the bounds of its own type variables. It is referenced indirectly through 'Hest'.
+// Try providing type arguments to 'Hest' here or to some other raw types in the bounds along the reference chain.
+// typedef void Fisk<TypeY extends Hest>();
+//              ^^^^
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_class_typedef_cycle.dart:10:19: Context: Bound of this variable references raw type 'Hest'.
+// typedef void Fisk<TypeY extends Hest>();
+//                   ^^^^^
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_class_typedef_cycle.dart:8:12: Context: Bound of this variable references raw type 'Fisk'.
+// class Hest<TypeX extends Fisk> {}
+//            ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef Fisk<unrelated TypeY extends core::Object* = dynamic> = () →* void;
+class Hest<TypeX extends () →* void> extends core::Object {
+  synthetic constructor •() → self::Hest<self::Hest::TypeX*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_co_inductive.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_co_inductive.dart.weak.modular.expect
new file mode 100644
index 0000000..a6180cf
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_co_inductive.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_co_inductive.dart:8:12: Error: Generic type 'Hest' can't be used without type arguments in the bounds of its own type variables.
+// Try providing type arguments to 'Hest' here.
+// class Hest<TypeX extends Hest> {}
+//            ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Hest<TypeX extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Hest<self::Hest::TypeX*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_co_inductive_for_each.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_co_inductive_for_each.dart.weak.modular.expect
new file mode 100644
index 0000000..3cc0758
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_co_inductive_for_each.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_co_inductive_for_each.dart:8:12: Error: Generic type 'Hest' can't be used without type arguments in the bounds of its own type variables.
+// Try providing type arguments to 'Hest' here.
+// class Hest<TypeX extends Hest, TypeY extends Hest> {}
+//            ^^^^^
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_co_inductive_for_each.dart:8:32: Error: Generic type 'Hest' can't be used without type arguments in the bounds of its own type variables.
+// Try providing type arguments to 'Hest' here.
+// class Hest<TypeX extends Hest, TypeY extends Hest> {}
+//                                ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Hest<TypeX extends core::Object* = dynamic, TypeY extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Hest<self::Hest::TypeX*, self::Hest::TypeY*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_co_inductive_no_dup.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_co_inductive_no_dup.dart.weak.modular.expect
new file mode 100644
index 0000000..637253f
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_co_inductive_no_dup.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_co_inductive_no_dup.dart:9:12: Error: Generic type 'Hest' can't be used without type arguments in the bounds of its own type variables.
+// Try providing type arguments to 'Hest' here.
+// class Hest<TypeX extends Map<Hest, Hest>> {}
+//            ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Hest<TypeX extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Hest<self::Hest::TypeX*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_folded_regress.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_folded_regress.dart.weak.modular.expect
new file mode 100644
index 0000000..f205aa6
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_folded_regress.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Hest<TypeX extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Hest<self::Hest::TypeX*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Fisk<TypeY extends self::Hest<self::Hest<core::Object*>*>*> extends core::Object {
+  synthetic constructor •() → self::Fisk<self::Fisk::TypeY*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_for_each.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_for_each.dart.weak.modular.expect
new file mode 100644
index 0000000..340e597
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_for_each.dart.weak.modular.expect
@@ -0,0 +1,54 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_for_each.dart:11:12: Error: Generic type 'Hest' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'Hest' here.
+// class Fisk<TypeY extends Hest, TypeZ extends Hest> {}
+//            ^^^^^
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_for_each.dart:9:12: Context: Bound of this variable references variable 'TypeX' from the same declaration.
+// class Hest<TypeX extends Hest<TypeX>> {}
+//            ^^^^^
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_for_each.dart:11:32: Error: Generic type 'Hest' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'Hest' here.
+// class Fisk<TypeY extends Hest, TypeZ extends Hest> {}
+//                                ^^^^^
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_for_each.dart:9:12: Context: Bound of this variable references variable 'TypeX' from the same declaration.
+// class Hest<TypeX extends Hest<TypeX>> {}
+//            ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Hest<TypeX extends self::Hest<self::Hest::TypeX*>* = self::Hest<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::Hest<self::Hest::TypeX*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Fisk<TypeY extends self::Hest<self::Hest<dynamic>*>* = dynamic, TypeZ extends self::Hest<self::Hest<dynamic>*>* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Fisk<self::Fisk::TypeY*, self::Fisk::TypeZ*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_from_compiled.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_from_compiled.dart.weak.modular.expect
new file mode 100644
index 0000000..5f8978b
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_from_compiled.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_from_compiled.dart:15:12: Error: Generic type 'LinkedListEntry' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'LinkedListEntry' here.
+// class Hest<X extends LinkedListEntry> {}
+//            ^
+//
+import self as self;
+import "dart:collection" as col;
+import "dart:core" as core;
+
+import "dart:collection";
+
+class Hest<X extends col::LinkedListEntry<col::LinkedListEntry<dynamic>>* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Hest<self::Hest::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_generic_function_in_bound_regress.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_generic_function_in_bound_regress.dart.weak.modular.expect
new file mode 100644
index 0000000..74416db
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_generic_function_in_bound_regress.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_generic_function_in_bound_regress.dart:11:12: Error: Type variables can't have generic function types in their bounds.
+// class Fisk<TypeY extends Function<TypeZ extends Hest<Null>>(TypeZ)> {}
+//            ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Hest<TypeX extends self::Hest<self::Hest::TypeX*>* = self::Hest<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::Hest<self::Hest::TypeX*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Fisk<TypeY extends <TypeZ extends self::Hest<Null>* = dynamic>(TypeZ*) →* dynamic = dynamic> extends core::Object {
+  synthetic constructor •() → self::Fisk<self::Fisk::TypeY*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_many.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_many.dart.weak.modular.expect
new file mode 100644
index 0000000..e411b58
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_many.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_many.dart:12:15: Error: Generic type 'Hest' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'Hest' here.
+// class Naebdyr<TypeZ extends Map<Hest, Fisk>> {}
+//               ^^^^^
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_many.dart:8:12: Context: Bound of this variable references variable 'TypeX' from the same declaration.
+// class Hest<TypeX extends Hest<TypeX>> {}
+//            ^^^^^
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_many.dart:12:15: Error: Generic type 'Fisk' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'Fisk' here.
+// class Naebdyr<TypeZ extends Map<Hest, Fisk>> {}
+//               ^^^^^
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_many.dart:10:12: Context: Bound of this variable references variable 'TypeY' from the same declaration.
+// class Fisk<TypeY extends Fisk<TypeY>> {}
+//            ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Hest<TypeX extends self::Hest<self::Hest::TypeX*>* = self::Hest<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::Hest<self::Hest::TypeX*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Fisk<TypeY extends self::Fisk<self::Fisk::TypeY*>* = self::Fisk<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::Fisk<self::Fisk::TypeY*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Naebdyr<TypeZ extends core::Map<self::Hest<self::Hest<dynamic>*>*, self::Fisk<self::Fisk<dynamic>*>*>* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Naebdyr<self::Naebdyr::TypeZ*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_many_libs_same_name_cycle.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_many_libs_same_name_cycle.dart.weak.modular.expect
new file mode 100644
index 0000000..0124e15
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_many_libs_same_name_cycle.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_many_libs_same_name_cycle.dart:11:7: Error: Generic type 'Hest' can't be used without type arguments in the bounds of its own type variables. It is referenced indirectly through 'Hest'.
+// Try providing type arguments to 'Hest' here or to some other raw types in the bounds along the reference chain.
+// class Hest<TypeX extends lib.Hest> {}
+//       ^^^^
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_many_libs_same_name_cycle.dart:11:12: Context: Bound of this variable references raw type 'Hest'.
+// class Hest<TypeX extends lib.Hest> {}
+//            ^^^^^
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_many_libs_same_name_cycle_lib.dart:16:12: Context: Bound of this variable references raw type 'Hest'.
+// class Hest<TypeY extends lib.Hest> {}
+//            ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///non_simple_many_libs_same_name_cycle_lib.dart" as lib;
+
+class Hest<TypeX extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Hest<self::Hest::TypeX*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+library non_simple_many_libs_same_name_cycle_lib;
+import self as self2;
+import "non_simple_many_libs_same_name_cycle.dart" as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///non_simple_many_libs_same_name_cycle.dart" as lib;
+
+class Hest<TypeY extends self::Hest<dynamic>*> extends core::Object {
+  synthetic constructor •() → self2::Hest<self2::Hest::TypeY*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_no_dup.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_no_dup.dart.weak.modular.expect
new file mode 100644
index 0000000..28d37ca
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_no_dup.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_no_dup.dart:11:12: Error: Generic type 'Hest' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'Hest' here.
+// class Fisk<TypeY extends Map<Hest, Hest>> {}
+//            ^^^^^
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_no_dup.dart:9:12: Context: Bound of this variable references variable 'TypeX' from the same declaration.
+// class Hest<TypeX extends Hest<TypeX>> {}
+//            ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Hest<TypeX extends self::Hest<self::Hest::TypeX*>* = self::Hest<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::Hest<self::Hest::TypeX*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Fisk<TypeY extends core::Map<self::Hest<self::Hest<dynamic>*>*, self::Hest<self::Hest<dynamic>*>*>* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Fisk<self::Fisk::TypeY*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_suppress_consequence.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_suppress_consequence.dart.weak.modular.expect
new file mode 100644
index 0000000..34ba795
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_suppress_consequence.dart.weak.modular.expect
@@ -0,0 +1,61 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_suppress_consequence.dart:11:12: Error: Generic type 'Hest' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'Hest' here.
+// class Fisk<TypeY extends Hest> {}
+//            ^^^^^
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_suppress_consequence.dart:9:12: Context: Bound of this variable references variable 'TypeX' from the same declaration.
+// class Hest<TypeX extends Hest<TypeX>> {}
+//            ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Hest<TypeX extends self::Hest<self::Hest::TypeX*>* = self::Hest<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::Hest<self::Hest::TypeX*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Fisk<TypeY extends self::Hest<self::Hest<dynamic>*>* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Fisk<self::Fisk::TypeY*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Naebdyr<TypeZ extends self::Fisk<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::Naebdyr<self::Naebdyr::TypeZ*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/non_simple_variables_from_same.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/non_simple_variables_from_same.dart.weak.modular.expect
new file mode 100644
index 0000000..5334658
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/non_simple_variables_from_same.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_variables_from_same.dart:12:12: Error: Generic type 'Hest' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'Hest' here.
+// class Fisk<TypeY extends Hest> {}
+//            ^^^^^
+// pkg/front_end/testcases/instantiate_to_bound/non_simple_variables_from_same.dart:10:12: Context: Bound of this variable references variable 'TypeX' from the same declaration.
+// class Hest<TypeX extends Hest<TypeX>> {}
+//            ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Hest<TypeX extends self::Hest<self::Hest::TypeX*>* = self::Hest<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::Hest<self::Hest::TypeX*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Fisk<TypeY extends self::Hest<self::Hest<dynamic>*>* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Fisk<self::Fisk::TypeY*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/omitted_bound.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/omitted_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..8000a5e
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/omitted_bound.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+import "dart:collection";
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method foo() → self::A<dynamic>*
+    return null;
+  method baz() → col::DoubleLinkedQueue<dynamic>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::A<dynamic>* a;
+static field col::DoubleLinkedQueue<dynamic>* c;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/raw_in_bound.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/raw_in_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..97505bc
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/raw_in_bound.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::num*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends self::A<core::num*>*> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/super_bounded_in_bound.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/super_bounded_in_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..5ec3988
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/super_bounded_in_bound.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Comparable<self::A::X*>* = core::Comparable<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<Y extends self::A<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::B<self::B::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/super_bounded_type.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/super_bounded_type.dart.weak.modular.expect
new file mode 100644
index 0000000..a0f95a2
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/super_bounded_type.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends self::A<self::A::T*>* = self::A<dynamic>*> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::A<self::A<dynamic>*>* a;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/supertypes.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/supertypes.dart.weak.modular.expect
new file mode 100644
index 0000000..fbb18cb
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/supertypes.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class X<T extends self::B*> extends core::Object {
+  synthetic constructor •() → self::X<self::X::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Y extends self::X<self::B*> {
+  synthetic constructor •() → self::Y*
+    : super self::X::•()
+    ;
+}
+static method main() → void {
+  exp::Expect::isTrue(new self::Y::•() is self::X<self::B*>*);
+}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/typedef_instantiated_in_outline.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/typedef_instantiated_in_outline.dart.weak.modular.expect
new file mode 100644
index 0000000..1e4c90a
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/typedef_instantiated_in_outline.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef A<contravariant T extends core::num*> = (T*) →* dynamic;
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method foo((core::num*) →* dynamic a) → dynamic
+    return null;
+  method bar() → (core::num*) →* dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/typedef_literal_list.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/typedef_literal_list.dart.weak.modular.expect
new file mode 100644
index 0000000..954f38c
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/typedef_literal_list.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef A<contravariant T extends core::num*> = (T*) →* dynamic;
+static field core::List<(core::num*) →* dynamic>* a = <(core::num*) →* dynamic>[];
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/typedef_literal_list_with_generic_argument.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/typedef_literal_list_with_generic_argument.dart.weak.modular.expect
new file mode 100644
index 0000000..8f09136
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/typedef_literal_list_with_generic_argument.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef A<contravariant T extends core::Object* = dynamic> = (T*) →* dynamic;
+class B<S extends core::Object* = dynamic> extends core::Object {
+  final field core::List<(self::B::S*) →* dynamic>* foo = <(self::B::S*) →* dynamic>[];
+  final field core::List<(core::num*) →* dynamic>* bar = <(core::num*) →* dynamic>[];
+  synthetic constructor •() → self::B<self::B::S*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/typedef_literal_map.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/typedef_literal_map.dart.weak.modular.expect
new file mode 100644
index 0000000..0914a2c
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/typedef_literal_map.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef A<contravariant T extends core::num*> = (T*) →* dynamic;
+static field core::Map<(core::num*) →* dynamic, (core::num*) →* dynamic>* a = <(core::num*) →* dynamic, (core::num*) →* dynamic>{};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/typedef_omitted_bound.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/typedef_omitted_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..900d197
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/typedef_omitted_bound.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef A<contravariant T extends core::Object* = dynamic> = (T*) →* dynamic;
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method foo() → (dynamic) →* dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field (dynamic) →* dynamic a;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/typedef_raw_in_bound.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/typedef_raw_in_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..f32d1b22
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/typedef_raw_in_bound.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef A<contravariant T extends core::num*> = (T*) →* dynamic;
+class B<T extends (core::num*) →* dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/instantiate_to_bound/typedef_super_bounded_type.dart.weak.modular.expect b/pkg/front_end/testcases/instantiate_to_bound/typedef_super_bounded_type.dart.weak.modular.expect
new file mode 100644
index 0000000..4280623
--- /dev/null
+++ b/pkg/front_end/testcases/instantiate_to_bound/typedef_super_bounded_type.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef A<contravariant T extends core::Object* = dynamic> = (T*) →* dynamic;
+typedef B<contravariant S extends (S*) →* dynamic = (dynamic) →* dynamic> = (S*) →* dynamic;
+static field ((dynamic) →* dynamic) →* dynamic b;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/late_lowering/compound.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/compound.dart.weak.modular.expect
new file mode 100644
index 0000000..eb987a6
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/compound.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/late_lowering/compound.dart:20:3: Error: Late variable 'local' without initializer is definitely unassigned.
+//   local += 0;
+//   ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+static method main() → dynamic {
+  lowered core::int? #local1;
+  lowered core::bool #local1#isSet = false;
+  function #local1#get() → core::int
+    return #local1#isSet ?{core::int} #local1{core::int} : throw new _in::LateError::localNI("local1");
+  function #local1#set(core::int #t1) → dynamic {
+    #local1#isSet = true;
+    return #local1 = #t1;
+  }
+  #local1#set(0){(core::int) → dynamic};
+  self::expect(0, #local1#get(){() → core::int});
+  #local1#set(#local1#get(){() → core::int}.{core::num::+}(2){(core::num) → core::int}){(core::int) → dynamic};
+  self::expect(2, #local1#get(){() → core::int});
+  lowered core::int? #local2;
+  lowered core::bool #local2#isSet = false;
+  function #local2#get() → core::int {
+    if(!#local2#isSet) {
+      #local2 = 1;
+      #local2#isSet = true;
+    }
+    return #local2{core::int};
+  }
+  function #local2#set(core::int #t2) → dynamic {
+    #local2#isSet = true;
+    return #local2 = #t2;
+  }
+  self::expect(1, #local2#get(){() → core::int});
+  #local2#set(#local2#get(){() → core::int}.{core::num::+}(2){(core::num) → core::int}){(core::int) → dynamic};
+  self::expect(3, #local2#get(){() → core::int});
+}
+static method error() → dynamic {
+  lowered final core::int? #local;
+  lowered core::bool #local#isSet = false;
+  function #local#get() → core::int
+    return #local#isSet ?{core::int} #local{core::int} : throw new _in::LateError::localNI("local");
+  function #local#set(core::int #t3) → dynamic
+    if(#local#isSet)
+      throw new _in::LateError::localAI("local");
+    else {
+      #local#isSet = true;
+      return #local = #t3;
+    }
+  #local#set(invalid-expression "pkg/front_end/testcases/late_lowering/compound.dart:20:3: Error: Late variable 'local' without initializer is definitely unassigned.
+  local += 0;
+  ^^^^^" in #local#get(){() → core::int}.{core::num::+}(0){(core::num) → core::int}){(core::int) → dynamic};
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/covariant_late_field.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/covariant_late_field.dart.weak.modular.expect
new file mode 100644
index 0000000..c2ac0b9
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/covariant_late_field.dart.weak.modular.expect
@@ -0,0 +1,65 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/late_lowering/covariant_late_field.dart:19:31: Error: The parameter 'value' of the method 'C.invariantField' has type 'int', which does not match the corresponding type, 'num', in the overridden method, 'A.invariantField'.
+// Change to a supertype of 'num', or, for a covariant parameter, a subtype.
+//   void set invariantField(int value) {} // error
+//                               ^
+// pkg/front_end/testcases/late_lowering/covariant_late_field.dart:6:12: Context: This is the overridden method ('invariantField').
+//   late num invariantField;
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class A extends core::Object {
+  field core::num? _#A#invariantField = null;
+  field core::bool _#A#invariantField#isSet = false;
+  field core::num? _#A#covariantField = null;
+  field core::bool _#A#covariantField#isSet = false;
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  get invariantField() → core::num
+    return this.{self::A::_#A#invariantField#isSet}{core::bool} ?{core::num} let final core::num? #t1 = this.{self::A::_#A#invariantField}{core::num?} in #t1{core::num} : throw new _in::LateError::fieldNI("invariantField");
+  set invariantField(core::num #t2) → void {
+    this.{self::A::_#A#invariantField#isSet} = true;
+    this.{self::A::_#A#invariantField} = #t2;
+  }
+  get covariantField() → core::num
+    return this.{self::A::_#A#covariantField#isSet}{core::bool} ?{core::num} let final core::num? #t3 = this.{self::A::_#A#covariantField}{core::num?} in #t3{core::num} : throw new _in::LateError::fieldNI("covariantField");
+  set covariantField(covariant-by-declaration core::num #t4) → void {
+    this.{self::A::_#A#covariantField#isSet} = true;
+    this.{self::A::_#A#covariantField} = #t4;
+  }
+}
+abstract class B extends core::Object implements self::A {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+  abstract get invariantField() → core::num;
+  abstract set invariantField(core::num value) → void;
+  abstract get covariantField() → core::num;
+  abstract set covariantField(covariant-by-declaration core::num value) → void;
+}
+abstract class C extends core::Object implements self::A {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  abstract get invariantField() → core::int;
+  set invariantField(core::int value) → void {}
+  abstract get covariantField() → core::int;
+  set covariantField(covariant-by-declaration core::int value) → void {}
+}
+abstract class D extends core::Object implements self::A {
+  synthetic constructor •() → self::D
+    : super core::Object::•()
+    ;
+  abstract get invariantField() → core::int;
+  set invariantField(covariant-by-declaration core::int value) → void {}
+  abstract get covariantField() → core::int;
+  set covariantField(covariant-by-declaration core::int value) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/late_lowering/definitely_assigned.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/definitely_assigned.dart.weak.modular.expect
new file mode 100644
index 0000000..28154dd
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/definitely_assigned.dart.weak.modular.expect
@@ -0,0 +1,299 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/late_lowering/definitely_assigned.dart:16:3: Error: Late final variable '#local2' definitely assigned.
+//   local2 = value; // error
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_assigned.dart:17:3: Error: Late final variable '#local4' definitely assigned.
+//   local4 = 0; // error
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_assigned.dart:18:3: Error: Late final variable '#local6' definitely assigned.
+//   local6 = 0; // error
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_assigned.dart:30:3: Error: Late final variable '#local2' definitely assigned.
+//   local2 = value; // error
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_assigned.dart:31:3: Error: Late final variable '#local4' definitely assigned.
+//   local4 = 0; // error
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_assigned.dart:32:3: Error: Late final variable '#local6' definitely assigned.
+//   local6 = 0; // error
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_assigned.dart:50:3: Error: Late final variable '#local2' definitely assigned.
+//   local2 = value; // error
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_assigned.dart:51:3: Error: Late final variable '#local4' definitely assigned.
+//   local4 = 0; // error
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_assigned.dart:52:3: Error: Late final variable '#local6' definitely assigned.
+//   local6 = 0; // error
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_assigned.dart:70:3: Error: Late final variable '#local2' definitely assigned.
+//   local2 = value; // error
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_assigned.dart:71:3: Error: Late final variable '#local4' definitely assigned.
+//   local4 = 0; // error
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_assigned.dart:72:3: Error: Late final variable '#local6' definitely assigned.
+//   local6 = 0; // error
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_assigned.dart:80:3: Error: Late final variable '#local4' definitely assigned.
+//   local4 += 0; // error
+//   ^^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_assigned.dart:88:3: Error: Late final variable '#local4' definitely assigned.
+//   local4 += 0; // error
+//   ^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+import "dart:async";
+
+static field <T extends core::Object? = dynamic>(T%) → Null fieldDirect = <T extends core::Object? = dynamic>(T% value) → Null {
+  lowered final T? #local2;
+  lowered core::bool #local2#isSet = false;
+  function #local2#get() → T%
+    return #local2#isSet ?{T%} #local2{T%} : throw new _in::LateError::localNI("local2");
+  function #local2#set(T% #t1) → dynamic
+    if(#local2#isSet)
+      throw new _in::LateError::localAI("local2");
+    else {
+      #local2#isSet = true;
+      return #local2 = #t1;
+    }
+  lowered final core::int? #local4;
+  lowered core::bool #local4#isSet = false;
+  function #local4#get() → core::int
+    return #local4#isSet ?{core::int} #local4{core::int} : throw new _in::LateError::localNI("local4");
+  function #local4#set(core::int #t2) → dynamic
+    if(#local4#isSet)
+      throw new _in::LateError::localAI("local4");
+    else {
+      #local4#isSet = true;
+      return #local4 = #t2;
+    }
+  lowered final FutureOr<core::int>? #local6;
+  lowered core::bool #local6#isSet = false;
+  function #local6#get() → FutureOr<core::int>
+    return #local6#isSet ?{FutureOr<core::int>} #local6{FutureOr<core::int>} : throw new _in::LateError::localNI("local6");
+  function #local6#set(FutureOr<core::int>#t3) → dynamic
+    if(#local6#isSet)
+      throw new _in::LateError::localAI("local6");
+    else {
+      #local6#isSet = true;
+      return #local6 = #t3;
+    }
+  #local2#set(value){(T%) → dynamic};
+  #local4#set(0){(core::int) → dynamic};
+  #local6#set(0){(FutureOr<core::int>) → dynamic};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_assigned.dart:30:3: Error: Late final variable '#local2' definitely assigned.
+  local2 = value; // error
+  ^^^^^^^" in #local2#set(value){(T%) → dynamic};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_assigned.dart:31:3: Error: Late final variable '#local4' definitely assigned.
+  local4 = 0; // error
+  ^^^^^^^" in #local4#set(0){(core::int) → dynamic};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_assigned.dart:32:3: Error: Late final variable '#local6' definitely assigned.
+  local6 = 0; // error
+  ^^^^^^^" in #local6#set(0){(FutureOr<core::int>) → dynamic};
+};
+static field <T extends core::Object? = dynamic>(core::bool, T%) → Null fieldConditional = <T extends core::Object? = dynamic>(core::bool b, T% value) → Null {
+  lowered final T? #local2;
+  lowered core::bool #local2#isSet = false;
+  function #local2#get() → T%
+    return #local2#isSet ?{T%} #local2{T%} : throw new _in::LateError::localNI("local2");
+  function #local2#set(T% #t4) → dynamic
+    if(#local2#isSet)
+      throw new _in::LateError::localAI("local2");
+    else {
+      #local2#isSet = true;
+      return #local2 = #t4;
+    }
+  lowered final core::int? #local4;
+  lowered core::bool #local4#isSet = false;
+  function #local4#get() → core::int
+    return #local4#isSet ?{core::int} #local4{core::int} : throw new _in::LateError::localNI("local4");
+  function #local4#set(core::int #t5) → dynamic
+    if(#local4#isSet)
+      throw new _in::LateError::localAI("local4");
+    else {
+      #local4#isSet = true;
+      return #local4 = #t5;
+    }
+  lowered final FutureOr<core::int>? #local6;
+  lowered core::bool #local6#isSet = false;
+  function #local6#get() → FutureOr<core::int>
+    return #local6#isSet ?{FutureOr<core::int>} #local6{FutureOr<core::int>} : throw new _in::LateError::localNI("local6");
+  function #local6#set(FutureOr<core::int>#t6) → dynamic
+    if(#local6#isSet)
+      throw new _in::LateError::localAI("local6");
+    else {
+      #local6#isSet = true;
+      return #local6 = #t6;
+    }
+  if(b) {
+    #local2#set(value){(T%) → dynamic};
+    #local4#set(0){(core::int) → dynamic};
+    #local6#set(0){(FutureOr<core::int>) → dynamic};
+  }
+  #local2#set(value){(T%) → dynamic};
+  #local4#set(0){(core::int) → dynamic};
+  #local6#set(0){(FutureOr<core::int>) → dynamic};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_assigned.dart:70:3: Error: Late final variable '#local2' definitely assigned.
+  local2 = value; // error
+  ^^^^^^^" in #local2#set(value){(T%) → dynamic};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_assigned.dart:71:3: Error: Late final variable '#local4' definitely assigned.
+  local4 = 0; // error
+  ^^^^^^^" in #local4#set(0){(core::int) → dynamic};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_assigned.dart:72:3: Error: Late final variable '#local6' definitely assigned.
+  local6 = 0; // error
+  ^^^^^^^" in #local6#set(0){(FutureOr<core::int>) → dynamic};
+};
+static field () → Null fieldCompound = () → Null {
+  lowered final core::int? #local4;
+  lowered core::bool #local4#isSet = false;
+  function #local4#get() → core::int
+    return #local4#isSet ?{core::int} #local4{core::int} : throw new _in::LateError::localNI("local4");
+  function #local4#set(core::int #t7) → dynamic
+    if(#local4#isSet)
+      throw new _in::LateError::localAI("local4");
+    else {
+      #local4#isSet = true;
+      return #local4 = #t7;
+    }
+  #local4#set(0){(core::int) → dynamic};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_assigned.dart:88:3: Error: Late final variable '#local4' definitely assigned.
+  local4 += 0; // error
+  ^^^^^^^" in #local4#set(#local4#get(){() → core::int}.{core::num::+}(0){(core::num) → core::int}){(core::int) → dynamic};
+};
+static method methodDirect<T extends core::Object? = dynamic>(self::methodDirect::T% value) → dynamic {
+  lowered final self::methodDirect::T? #local2;
+  lowered core::bool #local2#isSet = false;
+  function #local2#get() → self::methodDirect::T%
+    return #local2#isSet ?{self::methodDirect::T%} #local2{self::methodDirect::T%} : throw new _in::LateError::localNI("local2");
+  function #local2#set(self::methodDirect::T% #t8) → dynamic
+    if(#local2#isSet)
+      throw new _in::LateError::localAI("local2");
+    else {
+      #local2#isSet = true;
+      return #local2 = #t8;
+    }
+  lowered final core::int? #local4;
+  lowered core::bool #local4#isSet = false;
+  function #local4#get() → core::int
+    return #local4#isSet ?{core::int} #local4{core::int} : throw new _in::LateError::localNI("local4");
+  function #local4#set(core::int #t9) → dynamic
+    if(#local4#isSet)
+      throw new _in::LateError::localAI("local4");
+    else {
+      #local4#isSet = true;
+      return #local4 = #t9;
+    }
+  lowered final FutureOr<core::int>? #local6;
+  lowered core::bool #local6#isSet = false;
+  function #local6#get() → FutureOr<core::int>
+    return #local6#isSet ?{FutureOr<core::int>} #local6{FutureOr<core::int>} : throw new _in::LateError::localNI("local6");
+  function #local6#set(FutureOr<core::int>#t10) → dynamic
+    if(#local6#isSet)
+      throw new _in::LateError::localAI("local6");
+    else {
+      #local6#isSet = true;
+      return #local6 = #t10;
+    }
+  #local2#set(value){(self::methodDirect::T%) → dynamic};
+  #local4#set(0){(core::int) → dynamic};
+  #local6#set(0){(FutureOr<core::int>) → dynamic};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_assigned.dart:16:3: Error: Late final variable '#local2' definitely assigned.
+  local2 = value; // error
+  ^^^^^^^" in #local2#set(value){(self::methodDirect::T%) → dynamic};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_assigned.dart:17:3: Error: Late final variable '#local4' definitely assigned.
+  local4 = 0; // error
+  ^^^^^^^" in #local4#set(0){(core::int) → dynamic};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_assigned.dart:18:3: Error: Late final variable '#local6' definitely assigned.
+  local6 = 0; // error
+  ^^^^^^^" in #local6#set(0){(FutureOr<core::int>) → dynamic};
+}
+static method methodConditional<T extends core::Object? = dynamic>(core::bool b, self::methodConditional::T% value) → dynamic {
+  lowered final self::methodConditional::T? #local2;
+  lowered core::bool #local2#isSet = false;
+  function #local2#get() → self::methodConditional::T%
+    return #local2#isSet ?{self::methodConditional::T%} #local2{self::methodConditional::T%} : throw new _in::LateError::localNI("local2");
+  function #local2#set(self::methodConditional::T% #t11) → dynamic
+    if(#local2#isSet)
+      throw new _in::LateError::localAI("local2");
+    else {
+      #local2#isSet = true;
+      return #local2 = #t11;
+    }
+  lowered final core::int? #local4;
+  lowered core::bool #local4#isSet = false;
+  function #local4#get() → core::int
+    return #local4#isSet ?{core::int} #local4{core::int} : throw new _in::LateError::localNI("local4");
+  function #local4#set(core::int #t12) → dynamic
+    if(#local4#isSet)
+      throw new _in::LateError::localAI("local4");
+    else {
+      #local4#isSet = true;
+      return #local4 = #t12;
+    }
+  lowered final FutureOr<core::int>? #local6;
+  lowered core::bool #local6#isSet = false;
+  function #local6#get() → FutureOr<core::int>
+    return #local6#isSet ?{FutureOr<core::int>} #local6{FutureOr<core::int>} : throw new _in::LateError::localNI("local6");
+  function #local6#set(FutureOr<core::int>#t13) → dynamic
+    if(#local6#isSet)
+      throw new _in::LateError::localAI("local6");
+    else {
+      #local6#isSet = true;
+      return #local6 = #t13;
+    }
+  if(b) {
+    #local2#set(value){(self::methodConditional::T%) → dynamic};
+    #local4#set(0){(core::int) → dynamic};
+    #local6#set(0){(FutureOr<core::int>) → dynamic};
+  }
+  #local2#set(value){(self::methodConditional::T%) → dynamic};
+  #local4#set(0){(core::int) → dynamic};
+  #local6#set(0){(FutureOr<core::int>) → dynamic};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_assigned.dart:50:3: Error: Late final variable '#local2' definitely assigned.
+  local2 = value; // error
+  ^^^^^^^" in #local2#set(value){(self::methodConditional::T%) → dynamic};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_assigned.dart:51:3: Error: Late final variable '#local4' definitely assigned.
+  local4 = 0; // error
+  ^^^^^^^" in #local4#set(0){(core::int) → dynamic};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_assigned.dart:52:3: Error: Late final variable '#local6' definitely assigned.
+  local6 = 0; // error
+  ^^^^^^^" in #local6#set(0){(FutureOr<core::int>) → dynamic};
+}
+static method methodCompound() → dynamic {
+  lowered final core::int? #local4;
+  lowered core::bool #local4#isSet = false;
+  function #local4#get() → core::int
+    return #local4#isSet ?{core::int} #local4{core::int} : throw new _in::LateError::localNI("local4");
+  function #local4#set(core::int #t14) → dynamic
+    if(#local4#isSet)
+      throw new _in::LateError::localAI("local4");
+    else {
+      #local4#isSet = true;
+      return #local4 = #t14;
+    }
+  #local4#set(0){(core::int) → dynamic};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_assigned.dart:80:3: Error: Late final variable '#local4' definitely assigned.
+  local4 += 0; // error
+  ^^^^^^^" in #local4#set(#local4#get(){() → core::int}.{core::num::+}(0){(core::num) → core::int}){(core::int) → dynamic};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/late_lowering/definitely_unassigned.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/definitely_unassigned.dart.weak.modular.expect
new file mode 100644
index 0000000..5589982
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/definitely_unassigned.dart.weak.modular.expect
@@ -0,0 +1,383 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:16:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+//   local1; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:17:3: Error: Late variable 'local2' without initializer is definitely unassigned.
+//   local2; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:18:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+//   local3; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:19:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+//   local4; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:20:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+//   local5; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:21:3: Error: Late variable 'local6' without initializer is definitely unassigned.
+//   local6; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:34:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+//   local1; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:35:3: Error: Late variable 'local2' without initializer is definitely unassigned.
+//   local2; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:36:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+//   local3; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:37:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+//   local4; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:38:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+//   local5; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:39:3: Error: Late variable 'local6' without initializer is definitely unassigned.
+//   local6; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:62:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+//   local1; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:64:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+//   local3; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:66:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+//   local5; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:90:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+//   local1; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:92:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+//   local3; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:94:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+//   local5; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:103:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+//   local3 += 0; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:104:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+//   local4 += 0; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:111:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+//   local3 += 0; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:112:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+//   local4 += 0; // error
+//   ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+import "dart:async";
+
+static field <T extends core::Object? = dynamic>(T%) → Null fieldDirect = <T extends core::Object? = dynamic>(T% value) → Null {
+  T% local1;
+  lowered T? #local2;
+  lowered core::bool #local2#isSet = false;
+  function #local2#get() → T%
+    return #local2#isSet ?{T%} #local2{T%} : throw new _in::LateError::localNI("local2");
+  function #local2#set(T% #t1) → dynamic {
+    #local2#isSet = true;
+    return #local2 = #t1;
+  }
+  core::int local3;
+  lowered core::int? #local4;
+  lowered core::bool #local4#isSet = false;
+  function #local4#get() → core::int
+    return #local4#isSet ?{core::int} #local4{core::int} : throw new _in::LateError::localNI("local4");
+  function #local4#set(core::int #t2) → dynamic {
+    #local4#isSet = true;
+    return #local4 = #t2;
+  }
+  FutureOr<core::int>local5;
+  lowered FutureOr<core::int>? #local6;
+  lowered core::bool #local6#isSet = false;
+  function #local6#get() → FutureOr<core::int>
+    return #local6#isSet ?{FutureOr<core::int>} #local6{FutureOr<core::int>} : throw new _in::LateError::localNI("local6");
+  function #local6#set(FutureOr<core::int>#t3) → dynamic {
+    #local6#isSet = true;
+    return #local6 = #t3;
+  }
+  lowered T? #local7;
+  lowered core::bool #local7#isSet = false;
+  function #local7#get() → T% {
+    if(!#local7#isSet) {
+      #local7 = value;
+      #local7#isSet = true;
+    }
+    return #local7{T%};
+  }
+  function #local7#set(T% #t4) → dynamic {
+    #local7#isSet = true;
+    return #local7 = #t4;
+  }
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:34:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+  local1; // error
+  ^^^^^^" in local1;
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:35:3: Error: Late variable 'local2' without initializer is definitely unassigned.
+  local2; // error
+  ^^^^^^" in #local2#get(){() → T%};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:36:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+  local3; // error
+  ^^^^^^" in local3;
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:37:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+  local4; // error
+  ^^^^^^" in #local4#get(){() → core::int};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:38:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+  local5; // error
+  ^^^^^^" in local5;
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:39:3: Error: Late variable 'local6' without initializer is definitely unassigned.
+  local6; // error
+  ^^^^^^" in #local6#get(){() → FutureOr<core::int>};
+  #local7#get(){() → T%};
+};
+static field <T extends core::Object? = dynamic>(core::bool, T%) → Null fieldConditional = <T extends core::Object? = dynamic>(core::bool b, T% value) → Null {
+  T% local1;
+  lowered T? #local2;
+  lowered core::bool #local2#isSet = false;
+  function #local2#get() → T%
+    return #local2#isSet ?{T%} #local2{T%} : throw new _in::LateError::localNI("local2");
+  function #local2#set(T% #t5) → dynamic {
+    #local2#isSet = true;
+    return #local2 = #t5;
+  }
+  core::int local3;
+  lowered core::int? #local4;
+  lowered core::bool #local4#isSet = false;
+  function #local4#get() → core::int
+    return #local4#isSet ?{core::int} #local4{core::int} : throw new _in::LateError::localNI("local4");
+  function #local4#set(core::int #t6) → dynamic {
+    #local4#isSet = true;
+    return #local4 = #t6;
+  }
+  FutureOr<core::int>local5;
+  lowered FutureOr<core::int>? #local6;
+  lowered core::bool #local6#isSet = false;
+  function #local6#get() → FutureOr<core::int>
+    return #local6#isSet ?{FutureOr<core::int>} #local6{FutureOr<core::int>} : throw new _in::LateError::localNI("local6");
+  function #local6#set(FutureOr<core::int>#t7) → dynamic {
+    #local6#isSet = true;
+    return #local6 = #t7;
+  }
+  lowered T? #local7;
+  lowered core::bool #local7#isSet = false;
+  function #local7#get() → T% {
+    if(!#local7#isSet) {
+      #local7 = value;
+      #local7#isSet = true;
+    }
+    return #local7{T%};
+  }
+  function #local7#set(T% #t8) → dynamic {
+    #local7#isSet = true;
+    return #local7 = #t8;
+  }
+  if(b) {
+    local1 = value;
+    #local2#set(value){(T%) → dynamic};
+    local3 = 0;
+    #local4#set(0){(core::int) → dynamic};
+    local5 = 0;
+    #local6#set(0){(FutureOr<core::int>) → dynamic};
+    #local7#get(){() → T%};
+  }
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:90:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+  local1; // error
+  ^^^^^^" in local1;
+  #local2#get(){() → T%};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:92:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+  local3; // error
+  ^^^^^^" in local3;
+  #local4#get(){() → core::int};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:94:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+  local5; // error
+  ^^^^^^" in local5;
+  #local6#get(){() → FutureOr<core::int>};
+  #local7#get(){() → T%};
+};
+static field () → Null fieldCompound = () → Null {
+  core::int local3;
+  lowered core::int? #local4;
+  lowered core::bool #local4#isSet = false;
+  function #local4#get() → core::int
+    return #local4#isSet ?{core::int} #local4{core::int} : throw new _in::LateError::localNI("local4");
+  function #local4#set(core::int #t9) → dynamic {
+    #local4#isSet = true;
+    return #local4 = #t9;
+  }
+  local3 = invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:111:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+  local3 += 0; // error
+  ^^^^^^" in local3.{core::num::+}(0){(core::num) → core::int};
+  #local4#set(invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:112:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+  local4 += 0; // error
+  ^^^^^^" in #local4#get(){() → core::int}.{core::num::+}(0){(core::num) → core::int}){(core::int) → dynamic};
+};
+static method methodDirect<T extends core::Object? = dynamic>(self::methodDirect::T% value) → dynamic {
+  self::methodDirect::T% local1;
+  lowered self::methodDirect::T? #local2;
+  lowered core::bool #local2#isSet = false;
+  function #local2#get() → self::methodDirect::T%
+    return #local2#isSet ?{self::methodDirect::T%} #local2{self::methodDirect::T%} : throw new _in::LateError::localNI("local2");
+  function #local2#set(self::methodDirect::T% #t10) → dynamic {
+    #local2#isSet = true;
+    return #local2 = #t10;
+  }
+  core::int local3;
+  lowered core::int? #local4;
+  lowered core::bool #local4#isSet = false;
+  function #local4#get() → core::int
+    return #local4#isSet ?{core::int} #local4{core::int} : throw new _in::LateError::localNI("local4");
+  function #local4#set(core::int #t11) → dynamic {
+    #local4#isSet = true;
+    return #local4 = #t11;
+  }
+  FutureOr<core::int>local5;
+  lowered FutureOr<core::int>? #local6;
+  lowered core::bool #local6#isSet = false;
+  function #local6#get() → FutureOr<core::int>
+    return #local6#isSet ?{FutureOr<core::int>} #local6{FutureOr<core::int>} : throw new _in::LateError::localNI("local6");
+  function #local6#set(FutureOr<core::int>#t12) → dynamic {
+    #local6#isSet = true;
+    return #local6 = #t12;
+  }
+  lowered self::methodDirect::T? #local7;
+  lowered core::bool #local7#isSet = false;
+  function #local7#get() → self::methodDirect::T% {
+    if(!#local7#isSet) {
+      #local7 = value;
+      #local7#isSet = true;
+    }
+    return #local7{self::methodDirect::T%};
+  }
+  function #local7#set(self::methodDirect::T% #t13) → dynamic {
+    #local7#isSet = true;
+    return #local7 = #t13;
+  }
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:16:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+  local1; // error
+  ^^^^^^" in local1;
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:17:3: Error: Late variable 'local2' without initializer is definitely unassigned.
+  local2; // error
+  ^^^^^^" in #local2#get(){() → self::methodDirect::T%};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:18:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+  local3; // error
+  ^^^^^^" in local3;
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:19:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+  local4; // error
+  ^^^^^^" in #local4#get(){() → core::int};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:20:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+  local5; // error
+  ^^^^^^" in local5;
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:21:3: Error: Late variable 'local6' without initializer is definitely unassigned.
+  local6; // error
+  ^^^^^^" in #local6#get(){() → FutureOr<core::int>};
+  #local7#get(){() → self::methodDirect::T%};
+}
+static method methodConditional<T extends core::Object? = dynamic>(core::bool b, self::methodConditional::T% value) → dynamic {
+  self::methodConditional::T% local1;
+  lowered self::methodConditional::T? #local2;
+  lowered core::bool #local2#isSet = false;
+  function #local2#get() → self::methodConditional::T%
+    return #local2#isSet ?{self::methodConditional::T%} #local2{self::methodConditional::T%} : throw new _in::LateError::localNI("local2");
+  function #local2#set(self::methodConditional::T% #t14) → dynamic {
+    #local2#isSet = true;
+    return #local2 = #t14;
+  }
+  core::int local3;
+  lowered core::int? #local4;
+  lowered core::bool #local4#isSet = false;
+  function #local4#get() → core::int
+    return #local4#isSet ?{core::int} #local4{core::int} : throw new _in::LateError::localNI("local4");
+  function #local4#set(core::int #t15) → dynamic {
+    #local4#isSet = true;
+    return #local4 = #t15;
+  }
+  FutureOr<core::int>local5;
+  lowered FutureOr<core::int>? #local6;
+  lowered core::bool #local6#isSet = false;
+  function #local6#get() → FutureOr<core::int>
+    return #local6#isSet ?{FutureOr<core::int>} #local6{FutureOr<core::int>} : throw new _in::LateError::localNI("local6");
+  function #local6#set(FutureOr<core::int>#t16) → dynamic {
+    #local6#isSet = true;
+    return #local6 = #t16;
+  }
+  lowered self::methodConditional::T? #local7;
+  lowered core::bool #local7#isSet = false;
+  function #local7#get() → self::methodConditional::T% {
+    if(!#local7#isSet) {
+      #local7 = value;
+      #local7#isSet = true;
+    }
+    return #local7{self::methodConditional::T%};
+  }
+  function #local7#set(self::methodConditional::T% #t17) → dynamic {
+    #local7#isSet = true;
+    return #local7 = #t17;
+  }
+  if(b) {
+    local1 = value;
+    #local2#set(value){(self::methodConditional::T%) → dynamic};
+    local3 = 0;
+    #local4#set(0){(core::int) → dynamic};
+    local5 = 0;
+    #local6#set(0){(FutureOr<core::int>) → dynamic};
+    #local7#set(value){(self::methodConditional::T%) → dynamic};
+  }
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:62:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+  local1; // error
+  ^^^^^^" in local1;
+  #local2#get(){() → self::methodConditional::T%};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:64:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+  local3; // error
+  ^^^^^^" in local3;
+  #local4#get(){() → core::int};
+  invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:66:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+  local5; // error
+  ^^^^^^" in local5;
+  #local6#get(){() → FutureOr<core::int>};
+  #local7#get(){() → self::methodConditional::T%};
+}
+static method methodCompound() → dynamic {
+  core::int local3;
+  lowered core::int? #local4;
+  lowered core::bool #local4#isSet = false;
+  function #local4#get() → core::int
+    return #local4#isSet ?{core::int} #local4{core::int} : throw new _in::LateError::localNI("local4");
+  function #local4#set(core::int #t18) → dynamic {
+    #local4#isSet = true;
+    return #local4 = #t18;
+  }
+  local3 = invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:103:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+  local3 += 0; // error
+  ^^^^^^" in local3.{core::num::+}(0){(core::num) → core::int};
+  #local4#set(invalid-expression "pkg/front_end/testcases/late_lowering/definitely_unassigned.dart:104:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+  local4 += 0; // error
+  ^^^^^^" in #local4#get(){() → core::int}.{core::num::+}(0){(core::num) → core::int}){(core::int) → dynamic};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/late_lowering/getter_vs_setter_type.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/getter_vs_setter_type.dart.weak.modular.expect
new file mode 100644
index 0000000..12210ba
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/getter_vs_setter_type.dart.weak.modular.expect
@@ -0,0 +1,151 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/late_lowering/getter_vs_setter_type.dart:32:12: Error: The type 'int?' of the inherited getter 'B1.property6' is not a subtype of the type 'int' of the setter 'B2.property6'.
+//   void set property6(int i); // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/late_lowering/getter_vs_setter_type.dart:20:19: Context: This is the declaration of the getter 'B1.property6'.
+//   late final int? property6;
+//                   ^^^^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/getter_vs_setter_type.dart:32:26: Error: The parameter 'i' of the method 'B2.property6' has type 'int', which does not match the corresponding type, 'int?', in the overridden method, 'B1.property6'.
+// Change to a supertype of 'int?', or, for a covariant parameter, a subtype.
+//   void set property6(int i); // error
+//                          ^
+// pkg/front_end/testcases/late_lowering/getter_vs_setter_type.dart:20:19: Context: This is the overridden method ('property6').
+//   late final int? property6;
+//                   ^
+//
+// pkg/front_end/testcases/late_lowering/getter_vs_setter_type.dart:52:12: Error: The type 'int?' of the getter 'C2.property6' is not a subtype of the type 'int' of the inherited setter 'C1.property6'.
+//   int? get property6; // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/late_lowering/getter_vs_setter_type.dart:40:12: Context: This is the declaration of the setter 'C1.property6'.
+//   late int property6;
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/late_lowering/getter_vs_setter_type.dart:52:12: Error: The return type of the method 'C2.property6' is 'int?', which does not match the return type, 'int', of the overridden method, 'C1.property6'.
+// Change to a subtype of 'int'.
+//   int? get property6; // error
+//            ^
+// pkg/front_end/testcases/late_lowering/getter_vs_setter_type.dart:40:12: Context: This is the overridden method ('property6').
+//   late int property6;
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+abstract class A extends core::Object {
+  field core::int? _#A#property4 = null;
+  field core::bool _#A#property4#isSet = false;
+  field core::int? _#A#property5 = null;
+  field core::bool _#A#property5#isSet = false;
+  field core::int? _#A#property6 = null;
+  field core::bool _#A#property6#isSet = false;
+  constructor •(core::int property4, core::int? property5, core::int property6) → self::A
+    : self::A::_#A#property4#isSet = true, self::A::_#A#property4 = property4, self::A::_#A#property5#isSet = true, self::A::_#A#property5 = property5, self::A::_#A#property6#isSet = true, self::A::_#A#property6 = property6, super core::Object::•()
+    ;
+  get property4() → core::int
+    return this.{self::A::_#A#property4#isSet}{core::bool} ?{core::int} let final core::int? #t1 = this.{self::A::_#A#property4}{core::int?} in #t1{core::int} : throw new _in::LateError::fieldNI("property4");
+  set property4(core::int #t2) → void {
+    this.{self::A::_#A#property4#isSet} = true;
+    this.{self::A::_#A#property4} = #t2;
+  }
+  get property5() → core::int?
+    return this.{self::A::_#A#property5#isSet}{core::bool} ?{core::int?} this.{self::A::_#A#property5}{core::int?} : throw new _in::LateError::fieldNI("property5");
+  set property5(core::int? #t3) → void {
+    this.{self::A::_#A#property5#isSet} = true;
+    this.{self::A::_#A#property5} = #t3;
+  }
+  get property6() → core::int
+    return this.{self::A::_#A#property6#isSet}{core::bool} ?{core::int} let final core::int? #t4 = this.{self::A::_#A#property6}{core::int?} in #t4{core::int} : throw new _in::LateError::fieldNI("property6");
+  set property6(covariant-by-declaration core::int #t5) → void {
+    this.{self::A::_#A#property6#isSet} = true;
+    this.{self::A::_#A#property6} = #t5;
+  }
+}
+abstract class B1 extends core::Object {
+  field core::int? _#B1#property4 = null;
+  field core::bool _#B1#property4#isSet = false;
+  field core::int? _#B1#property5 = null;
+  field core::bool _#B1#property5#isSet = false;
+  field core::int? _#B1#property6 = null;
+  field core::bool _#B1#property6#isSet = false;
+  constructor •(core::int property4, core::int property5, core::int? property6) → self::B1
+    : self::B1::_#B1#property4#isSet = true, self::B1::_#B1#property4 = property4, self::B1::_#B1#property5#isSet = true, self::B1::_#B1#property5 = property5, self::B1::_#B1#property6#isSet = true, self::B1::_#B1#property6 = property6, super core::Object::•()
+    ;
+  get property4() → core::int
+    return this.{self::B1::_#B1#property4#isSet}{core::bool} ?{core::int} let final core::int? #t6 = this.{self::B1::_#B1#property4}{core::int?} in #t6{core::int} : throw new _in::LateError::fieldNI("property4");
+  set property4(core::int #t7) → void
+    if(this.{self::B1::_#B1#property4#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("property4");
+    else {
+      this.{self::B1::_#B1#property4#isSet} = true;
+      this.{self::B1::_#B1#property4} = #t7;
+    }
+  get property5() → core::int
+    return this.{self::B1::_#B1#property5#isSet}{core::bool} ?{core::int} let final core::int? #t8 = this.{self::B1::_#B1#property5}{core::int?} in #t8{core::int} : throw new _in::LateError::fieldNI("property5");
+  set property5(core::int #t9) → void
+    if(this.{self::B1::_#B1#property5#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("property5");
+    else {
+      this.{self::B1::_#B1#property5#isSet} = true;
+      this.{self::B1::_#B1#property5} = #t9;
+    }
+  get property6() → core::int?
+    return this.{self::B1::_#B1#property6#isSet}{core::bool} ?{core::int?} this.{self::B1::_#B1#property6}{core::int?} : throw new _in::LateError::fieldNI("property6");
+  set property6(core::int? #t10) → void
+    if(this.{self::B1::_#B1#property6#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("property6");
+    else {
+      this.{self::B1::_#B1#property6#isSet} = true;
+      this.{self::B1::_#B1#property6} = #t10;
+    }
+}
+abstract class B2 extends core::Object implements self::B1 {
+  synthetic constructor •() → self::B2
+    : super core::Object::•()
+    ;
+  abstract set property4(core::int i) → void;
+  abstract set property5(core::int? i) → void;
+  abstract set property6(core::int i) → void;
+}
+abstract class C1 extends core::Object {
+  field core::int? _#C1#property4 = null;
+  field core::bool _#C1#property4#isSet = false;
+  field core::int? _#C1#property5 = null;
+  field core::bool _#C1#property5#isSet = false;
+  field core::int? _#C1#property6 = null;
+  field core::bool _#C1#property6#isSet = false;
+  constructor •(core::int property4, core::int property5, core::int property6) → self::C1
+    : self::C1::_#C1#property4#isSet = true, self::C1::_#C1#property4 = property4, self::C1::_#C1#property5#isSet = true, self::C1::_#C1#property5 = property5, self::C1::_#C1#property6#isSet = true, self::C1::_#C1#property6 = property6, super core::Object::•()
+    ;
+  get property4() → core::int
+    return this.{self::C1::_#C1#property4#isSet}{core::bool} ?{core::int} let final core::int? #t11 = this.{self::C1::_#C1#property4}{core::int?} in #t11{core::int} : throw new _in::LateError::fieldNI("property4");
+  set property4(core::int #t12) → void {
+    this.{self::C1::_#C1#property4#isSet} = true;
+    this.{self::C1::_#C1#property4} = #t12;
+  }
+  get property5() → core::int
+    return this.{self::C1::_#C1#property5#isSet}{core::bool} ?{core::int} let final core::int? #t13 = this.{self::C1::_#C1#property5}{core::int?} in #t13{core::int} : throw new _in::LateError::fieldNI("property5");
+  set property5(core::int #t14) → void {
+    this.{self::C1::_#C1#property5#isSet} = true;
+    this.{self::C1::_#C1#property5} = #t14;
+  }
+  get property6() → core::int
+    return this.{self::C1::_#C1#property6#isSet}{core::bool} ?{core::int} let final core::int? #t15 = this.{self::C1::_#C1#property6}{core::int?} in #t15{core::int} : throw new _in::LateError::fieldNI("property6");
+  set property6(core::int #t16) → void {
+    this.{self::C1::_#C1#property6#isSet} = true;
+    this.{self::C1::_#C1#property6} = #t16;
+  }
+}
+abstract class C2 extends core::Object implements self::C1 {
+  synthetic constructor •() → self::C2
+    : super core::Object::•()
+    ;
+  abstract get property4() → core::int;
+  abstract get property5() → core::int;
+  abstract get property6() → core::int?;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/late_lowering/infer_from_late_variable.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/infer_from_late_variable.dart.weak.modular.expect
new file mode 100644
index 0000000..6d53db1
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/infer_from_late_variable.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+static method f<T extends core::Object? = dynamic>(self::f::T% t) → self::f::T%
+  return t;
+static method main() → dynamic {
+  lowered core::int? #local;
+  lowered core::bool #local#isSet = false;
+  function #local#get() → core::int
+    return #local#isSet ?{core::int} #local{core::int} : throw new _in::LateError::localNI("local");
+  function #local#set(core::int #t1) → dynamic {
+    #local#isSet = true;
+    return #local = #t1;
+  }
+  #local#set(self::f<core::int>(0)){(core::int) → dynamic};
+}
diff --git a/pkg/front_end/testcases/late_lowering/infer_late_field_type.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/infer_late_field_type.dart.weak.modular.expect
new file mode 100644
index 0000000..f6de289
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/infer_late_field_type.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class A extends core::Object {
+  field core::int? field = null;
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class B extends core::Object implements self::A {
+  field core::int? _#B#field = null;
+  field core::bool _#B#field#isSet = false;
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+  get field() → core::int?
+    return this.{self::B::_#B#field#isSet}{core::bool} ?{core::int?} this.{self::B::_#B#field}{core::int?} : throw new _in::LateError::fieldNI("field");
+  set field(core::int? #t1) → void {
+    this.{self::B::_#B#field#isSet} = true;
+    this.{self::B::_#B#field} = #t1;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/late_lowering/initializer_rewrite.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/initializer_rewrite.dart.weak.modular.expect
new file mode 100644
index 0000000..fdfbb02
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/initializer_rewrite.dart.weak.modular.expect
@@ -0,0 +1,107 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class extends core::Object {
+  static field core::int nonNullableStaticFieldReads = 0;
+  static field core::int? _#nonNullableStaticField = null;
+  static field core::bool _#nonNullableStaticField#isSet = false;
+  static field core::int nullableStaticFieldReads = 0;
+  static field core::int? _#nullableStaticField = null;
+  static field core::bool _#nullableStaticField#isSet = false;
+  field core::int nonNullableInstanceFieldReads = 0;
+  field core::int? _#Class#nonNullableInstanceField = null;
+  field core::bool _#Class#nonNullableInstanceField#isSet = false;
+  field core::int nullableInstanceFieldReads = 0;
+  field core::int? _#Class#nullableInstanceField = null;
+  field core::bool _#Class#nullableInstanceField#isSet = false;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  static get nonNullableStaticField() → core::int {
+    if(!self::Class::_#nonNullableStaticField#isSet) {
+      final core::int #t1 = (let final core::int #t2 = self::Class::nonNullableStaticFieldReads in let final core::int #t3 = self::Class::nonNullableStaticFieldReads = #t2.{core::num::+}(1){(core::num) → core::int} in #t2) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int} self::Class::nonNullableStaticField.{core::num::+}(1){(core::num) → core::int} : 0;
+      if(self::Class::_#nonNullableStaticField#isSet)
+        throw new _in::LateError::fieldADI("nonNullableStaticField");
+      self::Class::_#nonNullableStaticField = #t1;
+      self::Class::_#nonNullableStaticField#isSet = true;
+    }
+    return let final core::int? #t4 = self::Class::_#nonNullableStaticField in #t4{core::int};
+  }
+  static get nullableStaticField() → core::int? {
+    if(!self::Class::_#nullableStaticField#isSet) {
+      final core::int? #t5 = (let final core::int #t6 = self::Class::nullableStaticFieldReads in let final core::int #t7 = self::Class::nullableStaticFieldReads = #t6.{core::num::+}(1){(core::num) → core::int} in #t6) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int} self::Class::nullableStaticField.{core::Object::hashCode}{core::int} : 0;
+      if(self::Class::_#nullableStaticField#isSet)
+        throw new _in::LateError::fieldADI("nullableStaticField");
+      self::Class::_#nullableStaticField = #t5;
+      self::Class::_#nullableStaticField#isSet = true;
+    }
+    return self::Class::_#nullableStaticField;
+  }
+  get nonNullableInstanceField() → core::int {
+    if(!this.{self::Class::_#Class#nonNullableInstanceField#isSet}{core::bool}) {
+      final core::int #t8 = (let final core::int #t9 = this.{self::Class::nonNullableInstanceFieldReads}{core::int} in let final core::int #t10 = this.{self::Class::nonNullableInstanceFieldReads} = #t9.{core::num::+}(1){(core::num) → core::int} in #t9) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int} this.{self::Class::nonNullableInstanceField}{core::int}.{core::num::+}(1){(core::num) → core::int} : 0;
+      if(this.{self::Class::_#Class#nonNullableInstanceField#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("nonNullableInstanceField");
+      this.{self::Class::_#Class#nonNullableInstanceField} = #t8;
+      this.{self::Class::_#Class#nonNullableInstanceField#isSet} = true;
+    }
+    return let final core::int? #t11 = this.{self::Class::_#Class#nonNullableInstanceField}{core::int?} in #t11{core::int};
+  }
+  get nullableInstanceField() → core::int? {
+    if(!this.{self::Class::_#Class#nullableInstanceField#isSet}{core::bool}) {
+      final core::int? #t12 = (let final core::int #t13 = this.{self::Class::nullableInstanceFieldReads}{core::int} in let final core::int #t14 = this.{self::Class::nullableInstanceFieldReads} = #t13.{core::num::+}(1){(core::num) → core::int} in #t13) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int} this.{self::Class::nullableInstanceField}{core::int?}.{core::Object::hashCode}{core::int} : 0;
+      if(this.{self::Class::_#Class#nullableInstanceField#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("nullableInstanceField");
+      this.{self::Class::_#Class#nullableInstanceField} = #t12;
+      this.{self::Class::_#Class#nullableInstanceField#isSet} = true;
+    }
+    return this.{self::Class::_#Class#nullableInstanceField}{core::int?};
+  }
+}
+static field core::int nonNullableTopLevelFieldReads = 0;
+static field core::int? _#nonNullableTopLevelField = null;
+static field core::bool _#nonNullableTopLevelField#isSet = false;
+static field core::int nullableTopLevelFieldReads = 0;
+static field core::int? _#nullableTopLevelField = null;
+static field core::bool _#nullableTopLevelField#isSet = false;
+static get nonNullableTopLevelField() → core::int {
+  if(!self::_#nonNullableTopLevelField#isSet) {
+    final core::int #t15 = (let final core::int #t16 = self::nonNullableTopLevelFieldReads in let final core::int #t17 = self::nonNullableTopLevelFieldReads = #t16.{core::num::+}(1){(core::num) → core::int} in #t16) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int} self::nonNullableTopLevelField.{core::num::+}(1){(core::num) → core::int} : 0;
+    if(self::_#nonNullableTopLevelField#isSet)
+      throw new _in::LateError::fieldADI("nonNullableTopLevelField");
+    self::_#nonNullableTopLevelField = #t15;
+    self::_#nonNullableTopLevelField#isSet = true;
+  }
+  return let final core::int? #t18 = self::_#nonNullableTopLevelField in #t18{core::int};
+}
+static get nullableTopLevelField() → core::int? {
+  if(!self::_#nullableTopLevelField#isSet) {
+    final core::int? #t19 = (let final core::int #t20 = self::nullableTopLevelFieldReads in let final core::int #t21 = self::nullableTopLevelFieldReads = #t20.{core::num::+}(1){(core::num) → core::int} in #t20) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int} self::nullableTopLevelField.{core::Object::hashCode}{core::int} : 0;
+    if(self::_#nullableTopLevelField#isSet)
+      throw new _in::LateError::fieldADI("nullableTopLevelField");
+    self::_#nullableTopLevelField = #t19;
+    self::_#nullableTopLevelField#isSet = true;
+  }
+  return self::_#nullableTopLevelField;
+}
+static method main() → void {
+  self::throws(() → core::int => self::nonNullableTopLevelField, "Read nonNullableTopLevelField");
+  self::throws(() → core::int? => self::nullableTopLevelField, "Read nullableTopLevelField");
+  self::throws(() → core::int => self::Class::nonNullableStaticField, "Read nonNullableStaticField");
+  self::throws(() → core::int? => self::Class::nullableStaticField, "Read nullableStaticField");
+  self::throws(() → core::int => new self::Class::•().{self::Class::nonNullableInstanceField}{core::int}, "Read nonNullableInstanceField");
+  self::throws(() → core::int? => new self::Class::•().{self::Class::nullableInstanceField}{core::int?}, "Read nullableInstanceField");
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/initializer_rewrite_from_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/initializer_rewrite_from_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..c72d69f
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/initializer_rewrite_from_opt_out.dart.weak.modular.expect
@@ -0,0 +1,117 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "initializer_rewrite_from_opt_out_lib.dart" as ini;
+import "dart:_internal" as _in;
+
+import "org-dartlang-testcase:///initializer_rewrite_from_opt_out_lib.dart";
+
+class Class extends core::Object {
+  static field core::int nonNullableStaticFieldReads = 0;
+  static field core::int? _#nonNullableStaticField = null;
+  static field core::bool _#nonNullableStaticField#isSet = false;
+  static field core::int nullableStaticFieldReads = 0;
+  static field core::int? _#nullableStaticField = null;
+  static field core::bool _#nullableStaticField#isSet = false;
+  field core::int nonNullableInstanceFieldReads = 0;
+  field core::int? _#Class#nonNullableInstanceField = null;
+  field core::bool _#Class#nonNullableInstanceField#isSet = false;
+  field core::int nullableInstanceFieldReads = 0;
+  field core::int? _#Class#nullableInstanceField = null;
+  field core::bool _#Class#nullableInstanceField#isSet = false;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  static get nonNullableStaticField() → core::int {
+    if(!self::Class::_#nonNullableStaticField#isSet) {
+      final core::int #t1 = (let final core::int #t2 = self::Class::nonNullableStaticFieldReads in let final core::int #t3 = self::Class::nonNullableStaticFieldReads = #t2.{core::num::+}(1){(core::num) → core::int} in #t2) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int*} self::Class::nonNullableStaticField : ini::computeInitialValue();
+      if(self::Class::_#nonNullableStaticField#isSet)
+        throw new _in::LateError::fieldADI("nonNullableStaticField");
+      self::Class::_#nonNullableStaticField = #t1;
+      self::Class::_#nonNullableStaticField#isSet = true;
+    }
+    return let final core::int? #t4 = self::Class::_#nonNullableStaticField in #t4{core::int};
+  }
+  static get nullableStaticField() → core::int? {
+    if(!self::Class::_#nullableStaticField#isSet) {
+      final core::int? #t5 = (let final core::int #t6 = self::Class::nullableStaticFieldReads in let final core::int #t7 = self::Class::nullableStaticFieldReads = #t6.{core::num::+}(1){(core::num) → core::int} in #t6) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int?} self::Class::nullableStaticField : ini::computeInitialValue();
+      if(self::Class::_#nullableStaticField#isSet)
+        throw new _in::LateError::fieldADI("nullableStaticField");
+      self::Class::_#nullableStaticField = #t5;
+      self::Class::_#nullableStaticField#isSet = true;
+    }
+    return self::Class::_#nullableStaticField;
+  }
+  get nonNullableInstanceField() → core::int {
+    if(!this.{self::Class::_#Class#nonNullableInstanceField#isSet}{core::bool}) {
+      final core::int #t8 = (let final core::int #t9 = this.{self::Class::nonNullableInstanceFieldReads}{core::int} in let final core::int #t10 = this.{self::Class::nonNullableInstanceFieldReads} = #t9.{core::num::+}(1){(core::num) → core::int} in #t9) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int*} this.{self::Class::nonNullableInstanceField}{core::int} : ini::computeInitialValue();
+      if(this.{self::Class::_#Class#nonNullableInstanceField#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("nonNullableInstanceField");
+      this.{self::Class::_#Class#nonNullableInstanceField} = #t8;
+      this.{self::Class::_#Class#nonNullableInstanceField#isSet} = true;
+    }
+    return let final core::int? #t11 = this.{self::Class::_#Class#nonNullableInstanceField}{core::int?} in #t11{core::int};
+  }
+  get nullableInstanceField() → core::int? {
+    if(!this.{self::Class::_#Class#nullableInstanceField#isSet}{core::bool}) {
+      final core::int? #t12 = (let final core::int #t13 = this.{self::Class::nullableInstanceFieldReads}{core::int} in let final core::int #t14 = this.{self::Class::nullableInstanceFieldReads} = #t13.{core::num::+}(1){(core::num) → core::int} in #t13) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int?} this.{self::Class::nullableInstanceField}{core::int?} : ini::computeInitialValue();
+      if(this.{self::Class::_#Class#nullableInstanceField#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("nullableInstanceField");
+      this.{self::Class::_#Class#nullableInstanceField} = #t12;
+      this.{self::Class::_#Class#nullableInstanceField#isSet} = true;
+    }
+    return this.{self::Class::_#Class#nullableInstanceField}{core::int?};
+  }
+}
+static field core::int nonNullableTopLevelFieldReads = 0;
+static field core::int? _#nonNullableTopLevelField = null;
+static field core::bool _#nonNullableTopLevelField#isSet = false;
+static field core::int nullableTopLevelFieldReads = 0;
+static field core::int? _#nullableTopLevelField = null;
+static field core::bool _#nullableTopLevelField#isSet = false;
+static get nonNullableTopLevelField() → core::int {
+  if(!self::_#nonNullableTopLevelField#isSet) {
+    final core::int #t15 = (let final core::int #t16 = self::nonNullableTopLevelFieldReads in let final core::int #t17 = self::nonNullableTopLevelFieldReads = #t16.{core::num::+}(1){(core::num) → core::int} in #t16) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int*} self::nonNullableTopLevelField : ini::computeInitialValue();
+    if(self::_#nonNullableTopLevelField#isSet)
+      throw new _in::LateError::fieldADI("nonNullableTopLevelField");
+    self::_#nonNullableTopLevelField = #t15;
+    self::_#nonNullableTopLevelField#isSet = true;
+  }
+  return let final core::int? #t18 = self::_#nonNullableTopLevelField in #t18{core::int};
+}
+static get nullableTopLevelField() → core::int? {
+  if(!self::_#nullableTopLevelField#isSet) {
+    final core::int? #t19 = (let final core::int #t20 = self::nullableTopLevelFieldReads in let final core::int #t21 = self::nullableTopLevelFieldReads = #t20.{core::num::+}(1){(core::num) → core::int} in #t20) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int?} self::nullableTopLevelField : ini::computeInitialValue();
+    if(self::_#nullableTopLevelField#isSet)
+      throw new _in::LateError::fieldADI("nullableTopLevelField");
+    self::_#nullableTopLevelField = #t19;
+    self::_#nullableTopLevelField#isSet = true;
+  }
+  return self::_#nullableTopLevelField;
+}
+static method main() → void {
+  self::throws(() → core::int => self::nonNullableTopLevelField, "Read nonNullableTopLevelField");
+  self::throws(() → core::int? => self::nullableTopLevelField, "Read nullableTopLevelField");
+  self::throws(() → core::int => self::Class::nonNullableStaticField, "Read nonNullableStaticField");
+  self::throws(() → core::int? => self::Class::nullableStaticField, "Read nullableStaticField");
+  self::throws(() → core::int => new self::Class::•().{self::Class::nonNullableInstanceField}{core::int}, "Read nonNullableInstanceField");
+  self::throws(() → core::int? => new self::Class::•().{self::Class::nullableInstanceField}{core::int?}, "Read nullableInstanceField");
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
+
+library;
+import self as ini;
+import "dart:core" as core;
+
+static method computeInitialValue() → core::int*
+  return null;
diff --git a/pkg/front_end/testcases/late_lowering/injected_late_field_checks/main.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/injected_late_field_checks/main.dart.weak.modular.expect
new file mode 100644
index 0000000..75e0cf4
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/injected_late_field_checks/main.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+
+import "dart:test";
+
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as self2;
+import "dart:_internal" as _in;
+import "dart:core" as core;
+
+import "dart:_internal";
+
+@#C1
+class Class extends core::Object {
+  field core::int? _#Class#foo = null /* from org-dartlang-testcase:///patch_lib.dart */;
+  field core::bool _#Class#foo#isSet = false /* from org-dartlang-testcase:///patch_lib.dart */;
+  constructor bar() → self2::Class
+    : super core::Object::•()
+    ;
+  constructor baz(core::int foo) → self2::Class
+    : self2::Class::_#Class#foo#isSet = true, self2::Class::_#Class#foo = foo, super core::Object::•()
+    ;
+  get /* from org-dartlang-testcase:///patch_lib.dart */ foo() → core::int
+    return this.{self2::Class::_#Class#foo#isSet}{core::bool} ?{core::int} let final core::int? #t1 = this.{self2::Class::_#Class#foo}{core::int?} in #t1{core::int} : throw new _in::LateError::fieldNI("foo");
+  set /* from org-dartlang-testcase:///patch_lib.dart */ foo(core::int #t2) → void {
+    this.{self2::Class::_#Class#foo#isSet} = true;
+    this.{self2::Class::_#Class#foo} = #t2;
+  }
+}
+
+constants  {
+  #C1 = _in::_Patch {}
+}
diff --git a/pkg/front_end/testcases/late_lowering/instance_field_with_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/instance_field_with_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..ccb0618
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/instance_field_with_initializer.dart.weak.modular.expect
@@ -0,0 +1,102 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int? _#Class#field = null;
+  field core::bool _#Class#field#isSet = false;
+  constructor constructor1() → self::Class
+    : super core::Object::•()
+    ;
+  constructor constructor2(core::int field) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = field, super core::Object::•()
+    ;
+  constructor constructor3(core::int value) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = value.{core::num::+}(1){(core::num) → core::int}, super core::Object::•()
+    ;
+  constructor constructor4([core::int field = #C1]) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = field, super core::Object::•()
+    ;
+  get field() → core::int {
+    if(!this.{self::Class::_#Class#field#isSet}{core::bool}) {
+      this.{self::Class::_#Class#field} = 10;
+      this.{self::Class::_#Class#field#isSet} = true;
+    }
+    return let final core::int? #t1 = this.{self::Class::_#Class#field}{core::int?} in #t1{core::int};
+  }
+  set field(core::int #t2) → void {
+    this.{self::Class::_#Class#field#isSet} = true;
+    this.{self::Class::_#Class#field} = #t2;
+  }
+}
+class Subclass extends self::Class {
+  constructor constructor1() → self::Subclass
+    : super self::Class::constructor1()
+    ;
+  constructor constructor2(core::int value) → self::Subclass
+    : super self::Class::constructor2(value)
+    ;
+  constructor constructor3(core::int value) → self::Subclass
+    : super self::Class::constructor3(value)
+    ;
+  constructor constructor4([core::int value = #C2]) → self::Subclass
+    : super self::Class::constructor4(value)
+    ;
+}
+static method test1() → dynamic {
+  self::Class c1 = new self::Class::constructor1();
+  self::expect(10, c1.{self::Class::field}{core::int});
+  c1.{self::Class::field} = 16;
+  self::expect(16, c1.{self::Class::field}{core::int});
+  self::Class c2 = new self::Class::constructor2(42);
+  self::expect(42, c2.{self::Class::field}{core::int});
+  c2.{self::Class::field} = 43;
+  self::expect(43, c2.{self::Class::field}{core::int});
+  self::Class c3 = new self::Class::constructor3(87);
+  self::expect(88, c3.{self::Class::field}{core::int});
+  c3.{self::Class::field} = 89;
+  self::expect(89, c3.{self::Class::field}{core::int});
+  self::Class c4 = new self::Class::constructor4();
+  self::expect(42, c4.{self::Class::field}{core::int});
+  c4.{self::Class::field} = 43;
+  self::expect(43, c4.{self::Class::field}{core::int});
+  self::Class c5 = new self::Class::constructor4(123);
+  self::expect(123, c5.{self::Class::field}{core::int});
+  c5.{self::Class::field} = 124;
+  self::expect(124, c5.{self::Class::field}{core::int});
+}
+static method test2() → dynamic {
+  self::Subclass c1 = new self::Subclass::constructor1();
+  self::expect(10, c1.{self::Class::field}{core::int});
+  c1.{self::Class::field} = 16;
+  self::expect(16, c1.{self::Class::field}{core::int});
+  self::Subclass c2 = new self::Subclass::constructor2(42);
+  self::expect(42, c2.{self::Class::field}{core::int});
+  c2.{self::Class::field} = 43;
+  self::expect(43, c2.{self::Class::field}{core::int});
+  self::Subclass c3 = new self::Subclass::constructor3(87);
+  self::expect(88, c3.{self::Class::field}{core::int});
+  c3.{self::Class::field} = 89;
+  self::expect(89, c3.{self::Class::field}{core::int});
+  self::Subclass c4 = new self::Subclass::constructor4();
+  self::expect(87, c4.{self::Class::field}{core::int});
+  c4.{self::Class::field} = 88;
+  self::expect(88, c4.{self::Class::field}{core::int});
+  self::Subclass c5 = new self::Subclass::constructor4(123);
+  self::expect(123, c5.{self::Class::field}{core::int});
+  c5.{self::Class::field} = 124;
+  self::expect(124, c5.{self::Class::field}{core::int});
+}
+static method main() → dynamic {
+  self::test1();
+  self::test2();
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = 42
+  #C2 = 87
+}
diff --git a/pkg/front_end/testcases/late_lowering/instance_field_with_initializer.dart.weak.outline.expect b/pkg/front_end/testcases/late_lowering/instance_field_with_initializer.dart.weak.outline.expect
index fa7bd6a..6ae21b7 100644
--- a/pkg/front_end/testcases/late_lowering/instance_field_with_initializer.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/late_lowering/instance_field_with_initializer.dart.weak.outline.expect
@@ -11,7 +11,7 @@
     ;
   constructor constructor3(core::int value) → self::Class
     ;
-  constructor constructor4([core::int field]) → self::Class
+  constructor constructor4([core::int field = 42]) → self::Class
     ;
   get field() → core::int;
   set field(core::int #t1) → void;
@@ -23,7 +23,7 @@
     ;
   constructor constructor3(core::int value) → self::Subclass
     ;
-  constructor constructor4([core::int value]) → self::Subclass
+  constructor constructor4([core::int value = 87]) → self::Subclass
     ;
 }
 static method test1() → dynamic
diff --git a/pkg/front_end/testcases/late_lowering/instance_field_without_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/instance_field_without_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..b2fdacb
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/instance_field_without_initializer.dart.weak.modular.expect
@@ -0,0 +1,109 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class extends core::Object {
+  field core::int? _#Class#field = null;
+  field core::bool _#Class#field#isSet = false;
+  constructor constructor1() → self::Class
+    : super core::Object::•()
+    ;
+  constructor constructor2(core::int field) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = field, super core::Object::•()
+    ;
+  constructor constructor3(core::int value) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = value.{core::num::+}(1){(core::num) → core::int}, super core::Object::•()
+    ;
+  constructor constructor4([core::int field = #C1]) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = field, super core::Object::•()
+    ;
+  get field() → core::int
+    return this.{self::Class::_#Class#field#isSet}{core::bool} ?{core::int} let final core::int? #t1 = this.{self::Class::_#Class#field}{core::int?} in #t1{core::int} : throw new _in::LateError::fieldNI("field");
+  set field(core::int #t2) → void {
+    this.{self::Class::_#Class#field#isSet} = true;
+    this.{self::Class::_#Class#field} = #t2;
+  }
+}
+class Subclass extends self::Class {
+  constructor constructor1() → self::Subclass
+    : super self::Class::constructor1()
+    ;
+  constructor constructor2(core::int value) → self::Subclass
+    : super self::Class::constructor2(value)
+    ;
+  constructor constructor3(core::int value) → self::Subclass
+    : super self::Class::constructor3(value)
+    ;
+  constructor constructor4([core::int value = #C2]) → self::Subclass
+    : super self::Class::constructor4(value)
+    ;
+}
+static method test1() → dynamic {
+  self::Class c1 = new self::Class::constructor1();
+  self::throws(() → core::int => c1.{self::Class::field}{core::int}, "Read value from uninitialized Class.field");
+  c1.{self::Class::field} = 16;
+  self::expect(16, c1.{self::Class::field}{core::int});
+  self::Class c2 = new self::Class::constructor2(42);
+  self::expect(42, c2.{self::Class::field}{core::int});
+  c2.{self::Class::field} = 43;
+  self::expect(43, c2.{self::Class::field}{core::int});
+  self::Class c3 = new self::Class::constructor3(87);
+  self::expect(88, c3.{self::Class::field}{core::int});
+  c3.{self::Class::field} = 89;
+  self::expect(89, c3.{self::Class::field}{core::int});
+  self::Class c4 = new self::Class::constructor4();
+  self::expect(42, c4.{self::Class::field}{core::int});
+  c4.{self::Class::field} = 43;
+  self::expect(43, c4.{self::Class::field}{core::int});
+  self::Class c5 = new self::Class::constructor4(123);
+  self::expect(123, c5.{self::Class::field}{core::int});
+  c5.{self::Class::field} = 124;
+  self::expect(124, c5.{self::Class::field}{core::int});
+}
+static method test2() → dynamic {
+  self::Subclass c1 = new self::Subclass::constructor1();
+  self::throws(() → core::int => c1.{self::Class::field}{core::int}, "Read value from uninitialized Class.field");
+  c1.{self::Class::field} = 16;
+  self::expect(16, c1.{self::Class::field}{core::int});
+  self::Subclass c2 = new self::Subclass::constructor2(42);
+  self::expect(42, c2.{self::Class::field}{core::int});
+  c2.{self::Class::field} = 43;
+  self::expect(43, c2.{self::Class::field}{core::int});
+  self::Subclass c3 = new self::Subclass::constructor3(87);
+  self::expect(88, c3.{self::Class::field}{core::int});
+  c3.{self::Class::field} = 89;
+  self::expect(89, c3.{self::Class::field}{core::int});
+  self::Subclass c4 = new self::Subclass::constructor4();
+  self::expect(87, c4.{self::Class::field}{core::int});
+  c4.{self::Class::field} = 88;
+  self::expect(88, c4.{self::Class::field}{core::int});
+  self::Subclass c5 = new self::Subclass::constructor4(123);
+  self::expect(123, c5.{self::Class::field}{core::int});
+  c5.{self::Class::field} = 124;
+  self::expect(124, c5.{self::Class::field}{core::int});
+}
+static method main() → dynamic {
+  self::test1();
+  self::test2();
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
+
+constants  {
+  #C1 = 42
+  #C2 = 87
+}
diff --git a/pkg/front_end/testcases/late_lowering/instance_field_without_initializer.dart.weak.outline.expect b/pkg/front_end/testcases/late_lowering/instance_field_without_initializer.dart.weak.outline.expect
index f83a9eb..b454862 100644
--- a/pkg/front_end/testcases/late_lowering/instance_field_without_initializer.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/late_lowering/instance_field_without_initializer.dart.weak.outline.expect
@@ -11,7 +11,7 @@
     ;
   constructor constructor3(core::int value) → self::Class
     ;
-  constructor constructor4([core::int field]) → self::Class
+  constructor constructor4([core::int field = 42]) → self::Class
     ;
   get field() → core::int;
   set field(core::int #t1) → void;
@@ -23,7 +23,7 @@
     ;
   constructor constructor3(core::int value) → self::Subclass
     ;
-  constructor constructor4([core::int value]) → self::Subclass
+  constructor constructor4([core::int value = 87]) → self::Subclass
     ;
 }
 static method test1() → dynamic
diff --git a/pkg/front_end/testcases/late_lowering/instance_final_field_without_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/instance_final_field_without_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..463e342
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/instance_final_field_without_initializer.dart.weak.modular.expect
@@ -0,0 +1,114 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class extends core::Object {
+  field core::int? _#Class#field = null;
+  field core::bool _#Class#field#isSet = false;
+  constructor constructor1() → self::Class
+    : super core::Object::•()
+    ;
+  constructor constructor2(core::int field) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = field, super core::Object::•()
+    ;
+  constructor constructor3(core::int value) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = value.{core::num::+}(1){(core::num) → core::int}, super core::Object::•()
+    ;
+  constructor constructor4([core::int field = #C1]) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = field, super core::Object::•()
+    ;
+  get field() → core::int
+    return this.{self::Class::_#Class#field#isSet}{core::bool} ?{core::int} let final core::int? #t1 = this.{self::Class::_#Class#field}{core::int?} in #t1{core::int} : throw new _in::LateError::fieldNI("field");
+  set field(core::int #t2) → void
+    if(this.{self::Class::_#Class#field#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("field");
+    else {
+      this.{self::Class::_#Class#field#isSet} = true;
+      this.{self::Class::_#Class#field} = #t2;
+    }
+}
+class Subclass extends self::Class {
+  constructor constructor1() → self::Subclass
+    : super self::Class::constructor1()
+    ;
+  constructor constructor2(core::int value) → self::Subclass
+    : super self::Class::constructor2(value)
+    ;
+  constructor constructor3(core::int value) → self::Subclass
+    : super self::Class::constructor3(value)
+    ;
+  constructor constructor4([core::int value = #C2]) → self::Subclass
+    : super self::Class::constructor4(value)
+    ;
+}
+static method test1() → dynamic {
+  self::Class c1 = new self::Class::constructor1();
+  self::throws(() → core::int => c1.{self::Class::field}{core::int}, "Read value from uninitialized Class.field");
+  c1.{self::Class::field} = 16;
+  self::expect(16, c1.{self::Class::field}{core::int});
+  self::throws(() → core::int => c1.{self::Class::field} = 17, "Write value to initialized Class.field");
+  self::Class c2 = new self::Class::constructor2(42);
+  self::expect(42, c2.{self::Class::field}{core::int});
+  self::throws(() → core::int => c2.{self::Class::field} = 43, "Write value to initialized Class.field");
+  self::Class c3 = new self::Class::constructor3(87);
+  self::expect(88, c3.{self::Class::field}{core::int});
+  self::throws(() → core::int => c3.{self::Class::field} = 89, "Write value to initialized Class.field");
+  self::Class c4 = new self::Class::constructor4();
+  self::expect(42, c4.{self::Class::field}{core::int});
+  self::throws(() → core::int => c4.{self::Class::field} = 43, "Write value to initialized Class.field");
+  self::Class c5 = new self::Class::constructor4(123);
+  self::expect(123, c5.{self::Class::field}{core::int});
+  self::throws(() → core::int => c5.{self::Class::field} = 124, "Write value to initialized Class.field");
+  self::Class c6 = new self::Class::constructor1();
+  c6.{self::Class::field} = 32;
+  self::expect(32, c6.{self::Class::field}{core::int});
+  self::throws(() → core::int => c6.{self::Class::field} = 32, "Write value to initialized Class.field");
+}
+static method test2() → dynamic {
+  self::Subclass c1 = new self::Subclass::constructor1();
+  self::throws(() → core::int => c1.{self::Class::field}{core::int}, "Read value from uninitialized Class1.field");
+  c1.{self::Class::field} = 16;
+  self::expect(16, c1.{self::Class::field}{core::int});
+  self::throws(() → core::int => c1.{self::Class::field} = 17, "Write value to initialized Class.field");
+  self::Subclass c2 = new self::Subclass::constructor2(42);
+  self::expect(42, c2.{self::Class::field}{core::int});
+  self::throws(() → core::int => c2.{self::Class::field} = 43, "Write value to initialized Class.field");
+  self::Subclass c3 = new self::Subclass::constructor3(87);
+  self::expect(88, c3.{self::Class::field}{core::int});
+  self::throws(() → core::int => c3.{self::Class::field} = 89, "Write value to initialized Class.field");
+  self::Subclass c4 = new self::Subclass::constructor4();
+  self::expect(87, c4.{self::Class::field}{core::int});
+  self::throws(() → core::int => c4.{self::Class::field} = 88, "Write value to initialized Class.field");
+  self::Subclass c5 = new self::Subclass::constructor4(123);
+  self::expect(123, c5.{self::Class::field}{core::int});
+  self::throws(() → core::int => c5.{self::Class::field} = 124, "Write value to initialized Class.field");
+  self::Subclass c6 = new self::Subclass::constructor1();
+  c6.{self::Class::field} = 32;
+  self::expect(32, c6.{self::Class::field}{core::int});
+  self::throws(() → core::int => c6.{self::Class::field} = 32, "Write value to initialized Class.field");
+}
+static method main() → dynamic {
+  self::test1();
+  self::test2();
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
+
+constants  {
+  #C1 = 42
+  #C2 = 87
+}
diff --git a/pkg/front_end/testcases/late_lowering/instance_final_field_without_initializer.dart.weak.outline.expect b/pkg/front_end/testcases/late_lowering/instance_final_field_without_initializer.dart.weak.outline.expect
index f83a9eb..b454862 100644
--- a/pkg/front_end/testcases/late_lowering/instance_final_field_without_initializer.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/late_lowering/instance_final_field_without_initializer.dart.weak.outline.expect
@@ -11,7 +11,7 @@
     ;
   constructor constructor3(core::int value) → self::Class
     ;
-  constructor constructor4([core::int field]) → self::Class
+  constructor constructor4([core::int field = 42]) → self::Class
     ;
   get field() → core::int;
   set field(core::int #t1) → void;
@@ -23,7 +23,7 @@
     ;
   constructor constructor3(core::int value) → self::Subclass
     ;
-  constructor constructor4([core::int value]) → self::Subclass
+  constructor constructor4([core::int value = 87]) → self::Subclass
     ;
 }
 static method test1() → dynamic
diff --git a/pkg/front_end/testcases/late_lowering/instance_nullable_field_with_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/instance_nullable_field_with_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..5a147d7
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/instance_nullable_field_with_initializer.dart.weak.modular.expect
@@ -0,0 +1,104 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int? _#Class#field = null;
+  field core::bool _#Class#field#isSet = false;
+  constructor constructor1() → self::Class
+    : super core::Object::•()
+    ;
+  constructor constructor2(core::int? field) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = field, super core::Object::•()
+    ;
+  constructor constructor3(core::int value) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = value.{core::num::+}(1){(core::num) → core::int}, super core::Object::•()
+    ;
+  constructor constructor4([core::int? field = #C1]) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = field, super core::Object::•()
+    ;
+  get field() → core::int? {
+    if(!this.{self::Class::_#Class#field#isSet}{core::bool}) {
+      this.{self::Class::_#Class#field} = self::initField();
+      this.{self::Class::_#Class#field#isSet} = true;
+    }
+    return this.{self::Class::_#Class#field}{core::int?};
+  }
+  set field(core::int? #t1) → void {
+    this.{self::Class::_#Class#field#isSet} = true;
+    this.{self::Class::_#Class#field} = #t1;
+  }
+}
+class Subclass extends self::Class {
+  constructor constructor1() → self::Subclass
+    : super self::Class::constructor1()
+    ;
+  constructor constructor2(core::int value) → self::Subclass
+    : super self::Class::constructor2(value)
+    ;
+  constructor constructor3(core::int value) → self::Subclass
+    : super self::Class::constructor3(value)
+    ;
+  constructor constructor4([core::int value = #C2]) → self::Subclass
+    : super self::Class::constructor4(value)
+    ;
+}
+static method initField() → core::int?
+  return 10;
+static method test1() → dynamic {
+  self::Class c1 = new self::Class::constructor1();
+  self::expect(10, c1.{self::Class::field}{core::int?});
+  c1.{self::Class::field} = 16;
+  self::expect(16, c1.{self::Class::field}{core::int?});
+  self::Class c2 = new self::Class::constructor2(42);
+  self::expect(42, c2.{self::Class::field}{core::int?});
+  c2.{self::Class::field} = 43;
+  self::expect(43, c2.{self::Class::field}{core::int?});
+  self::Class c3 = new self::Class::constructor3(87);
+  self::expect(88, c3.{self::Class::field}{core::int?});
+  c3.{self::Class::field} = 89;
+  self::expect(89, c3.{self::Class::field}{core::int?});
+  self::Class c4 = new self::Class::constructor4();
+  self::expect(42, c4.{self::Class::field}{core::int?});
+  c4.{self::Class::field} = 43;
+  self::expect(43, c4.{self::Class::field}{core::int?});
+  self::Class c5 = new self::Class::constructor4(123);
+  self::expect(123, c5.{self::Class::field}{core::int?});
+  c5.{self::Class::field} = 124;
+  self::expect(124, c5.{self::Class::field}{core::int?});
+}
+static method test2() → dynamic {
+  self::Subclass c1 = new self::Subclass::constructor1();
+  self::expect(10, c1.{self::Class::field}{core::int?});
+  c1.{self::Class::field} = 16;
+  self::expect(16, c1.{self::Class::field}{core::int?});
+  self::Subclass c2 = new self::Subclass::constructor2(42);
+  self::expect(42, c2.{self::Class::field}{core::int?});
+  c2.{self::Class::field} = 43;
+  self::expect(43, c2.{self::Class::field}{core::int?});
+  self::Subclass c3 = new self::Subclass::constructor3(87);
+  self::expect(88, c3.{self::Class::field}{core::int?});
+  c3.{self::Class::field} = 89;
+  self::expect(89, c3.{self::Class::field}{core::int?});
+  self::Subclass c4 = new self::Subclass::constructor4();
+  self::expect(87, c4.{self::Class::field}{core::int?});
+  c4.{self::Class::field} = 88;
+  self::expect(88, c4.{self::Class::field}{core::int?});
+  self::Subclass c5 = new self::Subclass::constructor4(123);
+  self::expect(123, c5.{self::Class::field}{core::int?});
+  c5.{self::Class::field} = 124;
+  self::expect(124, c5.{self::Class::field}{core::int?});
+}
+static method main() → dynamic {
+  self::test1();
+  self::test2();
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = 42
+  #C2 = 87
+}
diff --git a/pkg/front_end/testcases/late_lowering/instance_nullable_field_with_initializer.dart.weak.outline.expect b/pkg/front_end/testcases/late_lowering/instance_nullable_field_with_initializer.dart.weak.outline.expect
index 511d101..dfec80d 100644
--- a/pkg/front_end/testcases/late_lowering/instance_nullable_field_with_initializer.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/late_lowering/instance_nullable_field_with_initializer.dart.weak.outline.expect
@@ -11,7 +11,7 @@
     ;
   constructor constructor3(core::int value) → self::Class
     ;
-  constructor constructor4([core::int? field]) → self::Class
+  constructor constructor4([core::int? field = 42]) → self::Class
     ;
   get field() → core::int?;
   set field(core::int? #t1) → void;
@@ -23,7 +23,7 @@
     ;
   constructor constructor3(core::int value) → self::Subclass
     ;
-  constructor constructor4([core::int value]) → self::Subclass
+  constructor constructor4([core::int value = 87]) → self::Subclass
     ;
 }
 static method initField() → core::int?
diff --git a/pkg/front_end/testcases/late_lowering/instance_nullable_field_without_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/instance_nullable_field_without_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..58f7272
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/instance_nullable_field_without_initializer.dart.weak.modular.expect
@@ -0,0 +1,109 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class extends core::Object {
+  field core::int? _#Class#field = null;
+  field core::bool _#Class#field#isSet = false;
+  constructor constructor1() → self::Class
+    : super core::Object::•()
+    ;
+  constructor constructor2(core::int? field) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = field, super core::Object::•()
+    ;
+  constructor constructor3(core::int value) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = value.{core::num::+}(1){(core::num) → core::int}, super core::Object::•()
+    ;
+  constructor constructor4([core::int? field = #C1]) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = field, super core::Object::•()
+    ;
+  get field() → core::int?
+    return this.{self::Class::_#Class#field#isSet}{core::bool} ?{core::int?} this.{self::Class::_#Class#field}{core::int?} : throw new _in::LateError::fieldNI("field");
+  set field(core::int? #t1) → void {
+    this.{self::Class::_#Class#field#isSet} = true;
+    this.{self::Class::_#Class#field} = #t1;
+  }
+}
+class Subclass extends self::Class {
+  constructor constructor1() → self::Subclass
+    : super self::Class::constructor1()
+    ;
+  constructor constructor2(core::int value) → self::Subclass
+    : super self::Class::constructor2(value)
+    ;
+  constructor constructor3(core::int value) → self::Subclass
+    : super self::Class::constructor3(value)
+    ;
+  constructor constructor4([core::int value = #C2]) → self::Subclass
+    : super self::Class::constructor4(value)
+    ;
+}
+static method test1() → dynamic {
+  self::Class c1 = new self::Class::constructor1();
+  self::throws(() → core::int? => c1.{self::Class::field}{core::int?}, "Read value from uninitialized Class.field");
+  c1.{self::Class::field} = 16;
+  self::expect(16, c1.{self::Class::field}{core::int?});
+  self::Class c2 = new self::Class::constructor2(42);
+  self::expect(42, c2.{self::Class::field}{core::int?});
+  c2.{self::Class::field} = 43;
+  self::expect(43, c2.{self::Class::field}{core::int?});
+  self::Class c3 = new self::Class::constructor3(87);
+  self::expect(88, c3.{self::Class::field}{core::int?});
+  c3.{self::Class::field} = 89;
+  self::expect(89, c3.{self::Class::field}{core::int?});
+  self::Class c4 = new self::Class::constructor4();
+  self::expect(42, c4.{self::Class::field}{core::int?});
+  c4.{self::Class::field} = 43;
+  self::expect(43, c4.{self::Class::field}{core::int?});
+  self::Class c5 = new self::Class::constructor4(123);
+  self::expect(123, c5.{self::Class::field}{core::int?});
+  c5.{self::Class::field} = 124;
+  self::expect(124, c5.{self::Class::field}{core::int?});
+}
+static method test2() → dynamic {
+  self::Subclass c1 = new self::Subclass::constructor1();
+  self::throws(() → core::int? => c1.{self::Class::field}{core::int?}, "Read value from uninitialized Class.field");
+  c1.{self::Class::field} = 16;
+  self::expect(16, c1.{self::Class::field}{core::int?});
+  self::Subclass c2 = new self::Subclass::constructor2(42);
+  self::expect(42, c2.{self::Class::field}{core::int?});
+  c2.{self::Class::field} = 43;
+  self::expect(43, c2.{self::Class::field}{core::int?});
+  self::Subclass c3 = new self::Subclass::constructor3(87);
+  self::expect(88, c3.{self::Class::field}{core::int?});
+  c3.{self::Class::field} = 89;
+  self::expect(89, c3.{self::Class::field}{core::int?});
+  self::Subclass c4 = new self::Subclass::constructor4();
+  self::expect(87, c4.{self::Class::field}{core::int?});
+  c4.{self::Class::field} = 88;
+  self::expect(88, c4.{self::Class::field}{core::int?});
+  self::Subclass c5 = new self::Subclass::constructor4(123);
+  self::expect(123, c5.{self::Class::field}{core::int?});
+  c5.{self::Class::field} = 124;
+  self::expect(124, c5.{self::Class::field}{core::int?});
+}
+static method main() → dynamic {
+  self::test1();
+  self::test2();
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
+
+constants  {
+  #C1 = 42
+  #C2 = 87
+}
diff --git a/pkg/front_end/testcases/late_lowering/instance_nullable_field_without_initializer.dart.weak.outline.expect b/pkg/front_end/testcases/late_lowering/instance_nullable_field_without_initializer.dart.weak.outline.expect
index 2ed3a81..4c71a87 100644
--- a/pkg/front_end/testcases/late_lowering/instance_nullable_field_without_initializer.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/late_lowering/instance_nullable_field_without_initializer.dart.weak.outline.expect
@@ -11,7 +11,7 @@
     ;
   constructor constructor3(core::int value) → self::Class
     ;
-  constructor constructor4([core::int? field]) → self::Class
+  constructor constructor4([core::int? field = 42]) → self::Class
     ;
   get field() → core::int?;
   set field(core::int? #t1) → void;
@@ -23,7 +23,7 @@
     ;
   constructor constructor3(core::int value) → self::Subclass
     ;
-  constructor constructor4([core::int value]) → self::Subclass
+  constructor constructor4([core::int value = 87]) → self::Subclass
     ;
 }
 static method test1() → dynamic
diff --git a/pkg/front_end/testcases/late_lowering/instance_nullable_final_field_without_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/instance_nullable_final_field_without_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..8bbbcaf
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/instance_nullable_final_field_without_initializer.dart.weak.modular.expect
@@ -0,0 +1,114 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class extends core::Object {
+  field core::int? _#Class#field = null;
+  field core::bool _#Class#field#isSet = false;
+  constructor constructor1() → self::Class
+    : super core::Object::•()
+    ;
+  constructor constructor2(core::int? field) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = field, super core::Object::•()
+    ;
+  constructor constructor3(core::int value) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = value.{core::num::+}(1){(core::num) → core::int}, super core::Object::•()
+    ;
+  constructor constructor4([core::int? field = #C1]) → self::Class
+    : self::Class::_#Class#field#isSet = true, self::Class::_#Class#field = field, super core::Object::•()
+    ;
+  get field() → core::int?
+    return this.{self::Class::_#Class#field#isSet}{core::bool} ?{core::int?} this.{self::Class::_#Class#field}{core::int?} : throw new _in::LateError::fieldNI("field");
+  set field(core::int? #t1) → void
+    if(this.{self::Class::_#Class#field#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("field");
+    else {
+      this.{self::Class::_#Class#field#isSet} = true;
+      this.{self::Class::_#Class#field} = #t1;
+    }
+}
+class Subclass extends self::Class {
+  constructor constructor1() → self::Subclass
+    : super self::Class::constructor1()
+    ;
+  constructor constructor2(core::int value) → self::Subclass
+    : super self::Class::constructor2(value)
+    ;
+  constructor constructor3(core::int value) → self::Subclass
+    : super self::Class::constructor3(value)
+    ;
+  constructor constructor4([core::int value = #C2]) → self::Subclass
+    : super self::Class::constructor4(value)
+    ;
+}
+static method test1() → dynamic {
+  self::Class c1 = new self::Class::constructor1();
+  self::throws(() → core::int? => c1.{self::Class::field}{core::int?}, "Read value from uninitialized Class.field");
+  c1.{self::Class::field} = 16;
+  self::expect(16, c1.{self::Class::field}{core::int?});
+  self::throws(() → core::int => c1.{self::Class::field} = 17, "Write value to initialized Class.field");
+  self::Class c2 = new self::Class::constructor2(42);
+  self::expect(42, c2.{self::Class::field}{core::int?});
+  self::throws(() → core::int => c2.{self::Class::field} = 43, "Write value to initialized Class.field");
+  self::Class c3 = new self::Class::constructor3(87);
+  self::expect(88, c3.{self::Class::field}{core::int?});
+  self::throws(() → core::int => c3.{self::Class::field} = 89, "Write value to initialized Class.field");
+  self::Class c4 = new self::Class::constructor4();
+  self::expect(42, c4.{self::Class::field}{core::int?});
+  self::throws(() → core::int => c4.{self::Class::field} = 43, "Write value to initialized Class.field");
+  self::Class c5 = new self::Class::constructor4(123);
+  self::expect(123, c5.{self::Class::field}{core::int?});
+  self::throws(() → core::int => c5.{self::Class::field} = 124, "Write value to initialized Class.field");
+  self::Class c6 = new self::Class::constructor1();
+  c6.{self::Class::field} = 32;
+  self::expect(32, c6.{self::Class::field}{core::int?});
+  self::throws(() → core::int => c6.{self::Class::field} = 32, "Write value to initialized Class.field");
+}
+static method test2() → dynamic {
+  self::Subclass c1 = new self::Subclass::constructor1();
+  self::throws(() → core::int? => c1.{self::Class::field}{core::int?}, "Read value from uninitialized Class1.field");
+  c1.{self::Class::field} = 16;
+  self::expect(16, c1.{self::Class::field}{core::int?});
+  self::throws(() → core::int => c1.{self::Class::field} = 17, "Write value to initialized Class.field");
+  self::Subclass c2 = new self::Subclass::constructor2(42);
+  self::expect(42, c2.{self::Class::field}{core::int?});
+  self::throws(() → core::int => c2.{self::Class::field} = 43, "Write value to initialized Class.field");
+  self::Subclass c3 = new self::Subclass::constructor3(87);
+  self::expect(88, c3.{self::Class::field}{core::int?});
+  self::throws(() → core::int => c3.{self::Class::field} = 89, "Write value to initialized Class.field");
+  self::Subclass c4 = new self::Subclass::constructor4();
+  self::expect(87, c4.{self::Class::field}{core::int?});
+  self::throws(() → core::int => c4.{self::Class::field} = 88, "Write value to initialized Class.field");
+  self::Subclass c5 = new self::Subclass::constructor4(123);
+  self::expect(123, c5.{self::Class::field}{core::int?});
+  self::throws(() → core::int => c5.{self::Class::field} = 124, "Write value to initialized Class.field");
+  self::Subclass c6 = new self::Subclass::constructor1();
+  c6.{self::Class::field} = 32;
+  self::expect(32, c6.{self::Class::field}{core::int?});
+  self::throws(() → core::int => c6.{self::Class::field} = 32, "Write value to initialized Class.field");
+}
+static method main() → dynamic {
+  self::test1();
+  self::test2();
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
+
+constants  {
+  #C1 = 42
+  #C2 = 87
+}
diff --git a/pkg/front_end/testcases/late_lowering/instance_nullable_final_field_without_initializer.dart.weak.outline.expect b/pkg/front_end/testcases/late_lowering/instance_nullable_final_field_without_initializer.dart.weak.outline.expect
index 2ed3a81..4c71a87 100644
--- a/pkg/front_end/testcases/late_lowering/instance_nullable_final_field_without_initializer.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/late_lowering/instance_nullable_final_field_without_initializer.dart.weak.outline.expect
@@ -11,7 +11,7 @@
     ;
   constructor constructor3(core::int value) → self::Class
     ;
-  constructor constructor4([core::int? field]) → self::Class
+  constructor constructor4([core::int? field = 42]) → self::Class
     ;
   get field() → core::int?;
   set field(core::int? #t1) → void;
@@ -23,7 +23,7 @@
     ;
   constructor constructor3(core::int value) → self::Subclass
     ;
-  constructor constructor4([core::int value]) → self::Subclass
+  constructor constructor4([core::int value = 87]) → self::Subclass
     ;
 }
 static method test1() → dynamic
diff --git a/pkg/front_end/testcases/late_lowering/issue40093.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/issue40093.dart.weak.modular.expect
new file mode 100644
index 0000000..fe10901
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/issue40093.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/late_lowering/issue40093.dart:6:8: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   for (late int i = 0; i < 10; ++i) {
+//        ^^^^
+//
+// pkg/front_end/testcases/late_lowering/issue40093.dart:9:8: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   for (late int i in <int>[]) {
+//        ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method error() → dynamic {
+  for (core::int i = 0; i.{core::num::<}(10){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+    core::print(i);
+  }
+  for (core::int i in <core::int>[]) {
+    core::print(i);
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/late_lowering/issue40373.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/issue40373.dart.weak.modular.expect
new file mode 100644
index 0000000..32f6e7c
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/issue40373.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class C extends core::Object {
+  field core::num pi = 3.14;
+  field core::num? _#C#p1 = null;
+  field core::bool _#C#p1#isSet = false;
+  field core::num? _#C#p2 = null;
+  field core::bool _#C#p2#isSet = false;
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  get p1() → core::num {
+    if(!this.{self::C::_#C#p1#isSet}{core::bool}) {
+      this.{self::C::_#C#p1} = this.{self::C::pi}{core::num};
+      this.{self::C::_#C#p1#isSet} = true;
+    }
+    return let final core::num? #t1 = this.{self::C::_#C#p1}{core::num?} in #t1{core::num};
+  }
+  set p1(core::num #t2) → void {
+    this.{self::C::_#C#p1#isSet} = true;
+    this.{self::C::_#C#p1} = #t2;
+  }
+  get p2() → core::num {
+    if(!this.{self::C::_#C#p2#isSet}{core::bool}) {
+      final core::num #t3 = this.{self::C::pi}{core::num};
+      if(this.{self::C::_#C#p2#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("p2");
+      this.{self::C::_#C#p2} = #t3;
+      this.{self::C::_#C#p2#isSet} = true;
+    }
+    return let final core::num? #t4 = this.{self::C::_#C#p2}{core::num?} in #t4{core::num};
+  }
+}
+static method main() → dynamic {
+  self::expect(3.14, new self::C::•().{self::C::p1}{core::num});
+  self::expect(3.14, new self::C::•().{self::C::p2}{core::num});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/issue40373b.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/issue40373b.dart.weak.modular.expect
new file mode 100644
index 0000000..149d652
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/issue40373b.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class C extends core::Object {
+  static field dynamic _#s = null;
+  static field core::bool _#s#isSet = false;
+  field dynamic _#C#v = null;
+  field core::bool _#C#v#isSet = false;
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  static get s() → dynamic
+    return self::C::_#s#isSet ?{dynamic} self::C::_#s : throw new _in::LateError::fieldNI("s");
+  static set s(dynamic #t1) → void
+    if(self::C::_#s#isSet)
+      throw new _in::LateError::fieldAI("s");
+    else {
+      self::C::_#s#isSet = true;
+      self::C::_#s = #t1;
+    }
+  get v() → dynamic
+    return this.{self::C::_#C#v#isSet}{core::bool} ?{dynamic} this.{self::C::_#C#v}{dynamic} : throw new _in::LateError::fieldNI("v");
+  set v(dynamic #t2) → void
+    if(this.{self::C::_#C#v#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("v");
+    else {
+      this.{self::C::_#C#v#isSet} = true;
+      this.{self::C::_#C#v} = #t2;
+    }
+}
+static field dynamic _#g = null;
+static field core::bool _#g#isSet = false;
+static get g() → dynamic
+  return self::_#g#isSet ?{dynamic} self::_#g : throw new _in::LateError::fieldNI("g");
+static set g(dynamic #t3) → void
+  if(self::_#g#isSet)
+    throw new _in::LateError::fieldAI("g");
+  else {
+    self::_#g#isSet = true;
+    self::_#g = #t3;
+  }
+static method main() → dynamic {
+  lowered final dynamic #l;
+  lowered core::bool #l#isSet = false;
+  function #l#get() → dynamic
+    return #l#isSet ?{dynamic} #l : throw new _in::LateError::localNI("l");
+  function #l#set(dynamic #t4) → dynamic
+    if(#l#isSet)
+      throw new _in::LateError::localAI("l");
+    else {
+      #l#isSet = true;
+      return #l = #t4;
+    }
+  self::g = "Lily";
+  self::C::s = "was";
+  self::C c = new self::C::•();
+  c.{self::C::v} = "here";
+  #l#set("Run, Forrest, run"){(dynamic) → dynamic};
+  self::expect("Lily", self::g);
+  self::expect("was", self::C::s);
+  self::expect("here", c.{self::C::v}{dynamic});
+  self::expect("Run, Forrest, run", #l#get(){() → dynamic});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/issue40601.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/issue40601.dart.weak.modular.expect
new file mode 100644
index 0000000..e8923f9
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/issue40601.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+abstract class A<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+  abstract method baz() → self::A::T%;
+  method bar(covariant-by-class self::A::T% value) → dynamic {}
+  method foo() → dynamic {
+    lowered self::A::T? #value;
+    lowered core::bool #value#isSet = false;
+    function #value#get() → self::A::T%
+      return #value#isSet ?{self::A::T%} #value{self::A::T%} : throw new _in::LateError::localNI("value");
+    function #value#set(self::A::T% #t1) → dynamic {
+      #value#isSet = true;
+      return #value = #t1;
+    }
+    () → dynamic result = () → dynamic => this.{self::A::bar}(#value#get(){() → self::A::T%}){(self::A::T%) → dynamic};
+    (() → Null {
+      #value#set(this.{self::A::baz}(){() → self::A::T%}){(self::A::T%) → dynamic};
+    })(){() → Null};
+    return result;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/late_lowering/issue40805.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/issue40805.dart.weak.modular.expect
new file mode 100644
index 0000000..a37d11f
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/issue40805.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class C extends core::Object {
+  field core::int? _#C#x = null;
+  field core::bool _#C#x#isSet = false;
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  get x() → core::int
+    return this.{self::C::_#C#x#isSet}{core::bool} ?{core::int} let final core::int? #t1 = this.{self::C::_#C#x}{core::int?} in #t1{core::int} : throw new _in::LateError::fieldNI("x");
+  set x(covariant-by-declaration core::int #t2) → void
+    if(this.{self::C::_#C#x#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("x");
+    else {
+      this.{self::C::_#C#x#isSet} = true;
+      this.{self::C::_#C#x} = #t2;
+    }
+}
+class D extends self::C {
+  synthetic constructor •() → self::D
+    : super self::C::•()
+    ;
+  set x(covariant-by-declaration core::num value) → void {
+    super.{self::C::x} = value.{core::num::toInt}(){() → core::int};
+  }
+}
+static method main() → dynamic {
+  new self::D::•().{self::D::x} = 3.14;
+}
diff --git a/pkg/front_end/testcases/late_lowering/issue41436/issue41436.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/issue41436/issue41436.dart.weak.modular.expect
new file mode 100644
index 0000000..c3f8ab3
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/issue41436/issue41436.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:test" as test;
+
+import "dart:test";
+
+static method main() → dynamic {
+  test::A a;
+}
+
+library /*isNonNullableByDefault*/;
+import self as test;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+abstract class A extends core::Object {
+  field core::int? _#A#x = null;
+  field core::bool _#A#x#isSet = false;
+  synthetic constructor •() → test::A
+    : super core::Object::•()
+    ;
+  get x() → core::int
+    return this.{test::A::_#A#x#isSet}{core::bool} ?{core::int} let final core::int? #t1 = this.{test::A::_#A#x}{core::int?} in #t1{core::int} : throw new _in::LateError::fieldNI("x");
+  set x(core::int #t2) → void {
+    this.{test::A::_#A#x#isSet} = true;
+    this.{test::A::_#A#x} = #t2;
+  }
+}
+class _B extends core::Object implements test::A {
+  field core::int x = 3;
+  synthetic constructor •() → test::_B
+    : super core::Object::•()
+    ;
+}
diff --git a/pkg/front_end/testcases/late_lowering/issue41436b.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/issue41436b.dart.weak.modular.expect
new file mode 100644
index 0000000..0c45d0a
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/issue41436b.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+abstract class A extends core::Object {
+  field core::int? _#A#x = null;
+  field core::bool _#A#x#isSet = false;
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  get x() → core::int
+    return this.{self::A::_#A#x#isSet}{core::bool} ?{core::int} let final core::int? #t1 = this.{self::A::_#A#x}{core::int?} in #t1{core::int} : throw new _in::LateError::fieldNI("x");
+  set x(core::int #t2) → void {
+    this.{self::A::_#A#x#isSet} = true;
+    this.{self::A::_#A#x} = #t2;
+  }
+}
+class _B extends core::Object implements self::A {
+  field core::int x = 3;
+  synthetic constructor •() → self::_B
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {
+  self::A a;
+}
diff --git a/pkg/front_end/testcases/late_lowering/issue41436c/issue41436c.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/issue41436c/issue41436c.dart.weak.modular.expect
new file mode 100644
index 0000000..4a82ef6
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/issue41436c/issue41436c.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "issue41436c_lib.dart" as iss;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue41436c_lib.dart";
+
+class C extends iss::B {
+  synthetic constructor •() → self::C
+    : super iss::B::•()
+    ;
+  no-such-method-forwarder get /* from org-dartlang-testcase:///issue41436c_lib.dart */ _#A#x#isSet() → core::bool
+    return this.{core::Object::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool;
+  no-such-method-forwarder get /* from org-dartlang-testcase:///issue41436c_lib.dart */ _#A#x() → core::int?
+    return this.{core::Object::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int?;
+  no-such-method-forwarder set /* from org-dartlang-testcase:///issue41436c_lib.dart */ _#A#x#isSet(core::bool value) → void
+    return this.{core::Object::noSuchMethod}(new core::_InvocationMirror::_withType(#C6, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation) → dynamic};
+  no-such-method-forwarder set /* from org-dartlang-testcase:///issue41436c_lib.dart */ _#A#x(core::int? value) → void
+    return this.{core::Object::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation) → dynamic};
+}
+static method main() → dynamic {
+  new self::C::•();
+}
+
+constants  {
+  #C1 = #org-dartlang-testcase:///issue41436c.dart::_#A#x#isSet
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+  #C5 = #org-dartlang-testcase:///issue41436c.dart::_#A#x
+  #C6 = #org-dartlang-testcase:///issue41436c.dart::_#A#x#isSet=
+  #C7 = #org-dartlang-testcase:///issue41436c.dart::_#A#x=
+}
diff --git a/pkg/front_end/testcases/late_lowering/issue41922.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/issue41922.dart.weak.modular.expect
new file mode 100644
index 0000000..f4abe91
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/issue41922.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::String? _#s = null;
+  static field core::bool _#s#isSet = false;
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  static get s() → core::String? {
+    if(!self::C::_#s#isSet) {
+      self::C::_#s = self::init("lateValue");
+      self::C::_#s#isSet = true;
+    }
+    return self::C::_#s;
+  }
+  static set s(core::String? #t1) → void {
+    self::C::_#s#isSet = true;
+    self::C::_#s = #t1;
+  }
+}
+static field core::bool _called = false;
+static method init(core::String val) → core::String {
+  if(!self::_called) {
+    self::_called = true;
+    throw core::Exception::•();
+  }
+  return val;
+}
+static method main() → dynamic {
+  self::throws(() → void {
+    self::C::s;
+  });
+  self::expect("lateValue", self::C::s);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → void f) → dynamic {
+  try {
+    f(){() → void};
+  }
+  on core::Object catch(final core::Object _) {
+    return;
+  }
+  throw "Expected exception";
+}
diff --git a/pkg/front_end/testcases/late_lowering/issue42407.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/issue42407.dart.weak.modular.expect
new file mode 100644
index 0000000..16c8e79
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/issue42407.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class A<T extends core::Object? = dynamic> extends core::Object {
+  covariant-by-class field self::A::T? _#A#x = null;
+  field core::bool _#A#x#isSet = false;
+  synthetic constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+  get x() → self::A::T%
+    return this.{self::A::_#A#x#isSet}{core::bool} ?{self::A::T%} let final self::A::T? #t1 = this.{self::A::_#A#x}{self::A::T?} in #t1{self::A::T%} : throw new _in::LateError::fieldNI("x");
+  set x(covariant-by-class self::A::T% #t2) → void {
+    this.{self::A::_#A#x#isSet} = true;
+    this.{self::A::_#A#x} = #t2;
+  }
+}
+class B<T extends core::Object? = dynamic> extends core::Object {
+  covariant-by-class field self::B::T? _y = null;
+  synthetic constructor •() → self::B<self::B::T%>
+    : super core::Object::•()
+    ;
+  get y() → self::B::T?
+    return this.{self::B::_y}{self::B::T?};
+  set y(covariant-by-class self::B::T? val) → void {
+    this.{self::B::_y} = val;
+  }
+}
+static method main() → dynamic {
+  self::A<core::num> a = new self::A::•<core::int>();
+  self::expect(42, a.{self::A::x} = 42);
+  self::throws(() → void => a.{self::A::x} = 0.5);
+  self::B<core::num> b = new self::B::•<core::int>();
+  self::expect(42, b.{self::B::y} = 42);
+  self::throws(() → void => b.{self::B::y} = 0.5);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → void f) → dynamic {
+  try {
+    f(){() → void};
+  }
+  on core::Object catch(final core::Object _) {
+    return;
+  }
+  throw "Expected exception";
+}
diff --git a/pkg/front_end/testcases/late_lowering/issue44372.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/issue44372.dart.weak.modular.expect
new file mode 100644
index 0000000..57a90e0
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/issue44372.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+static method main(core::List<core::String> args) → dynamic {
+  lowered () →? core::int #recursiveInitLocal;
+  lowered core::bool #recursiveInitLocal#isSet = false;
+  function #recursiveInitLocal#get() → () → core::int
+    return #recursiveInitLocal#isSet ?{() → core::int} #recursiveInitLocal{() → core::int} : throw new _in::LateError::localNI("recursiveInitLocal");
+  function #recursiveInitLocal#set(() → core::int #t1) → dynamic {
+    #recursiveInitLocal#isSet = true;
+    return #recursiveInitLocal = #t1;
+  }
+  lowered final core::int? #local;
+  lowered core::bool #local#isSet = false;
+  function #local#get() → core::int {
+    if(!#local#isSet) {
+      final core::int #t2 = #recursiveInitLocal#get(){() → () → core::int}(){() → core::int};
+      if(#local#isSet)
+        throw new _in::LateError::localADI("local");
+      #local = #t2;
+      #local#isSet = true;
+    }
+    return #local{core::int};
+  }
+  core::bool doRecursiveInitLocal = true;
+  #recursiveInitLocal#set(() → core::int {
+    core::print("Executing initializer");
+    if(doRecursiveInitLocal) {
+      doRecursiveInitLocal = false;
+      core::print("Trigger recursive initialization");
+      core::int val = #local#get(){() → core::int};
+      core::print("Final local has value ${val}");
+      core::print("Returning 4 from initializer");
+      return 4;
+    }
+    core::print("Returning 3 from initializer");
+    return 3;
+  }){(() → core::int) → dynamic};
+  self::throws(() → Null {
+    core::int val = #local#get(){() → core::int};
+    core::print("Final local has value ${val}");
+  }, "Read local");
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_annotations.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_annotations.dart.weak.modular.expect
new file mode 100644
index 0000000..784ff0c
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_annotations.dart.weak.modular.expect
@@ -0,0 +1,277 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Annotation extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::Annotation
+    : super core::Object::•()
+    ;
+}
+class A extends core::Object {
+  field core::int? _#A#instanceField = null;
+  field core::bool _#A#instanceField#isSet = false;
+  field core::int? _#A#finalInstanceField = null;
+  field core::bool _#A#finalInstanceField#isSet = false;
+  field core::int? _#A#finalInstanceFieldWithInitializer = null;
+  field core::bool _#A#finalInstanceFieldWithInitializer#isSet = false;
+  field core::num? _#A#covariantInstanceField = null;
+  field core::bool _#A#covariantInstanceField#isSet = false;
+  static field core::int? _#staticField = null;
+  static field core::bool _#staticField#isSet = false;
+  static field core::int? _#finalStaticField = null;
+  static field core::bool _#finalStaticField#isSet = false;
+  static field core::int? _#finalStaticFieldWithInitializer = null;
+  static field core::bool _#finalStaticFieldWithInitializer#isSet = false;
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  @#C1
+  get instanceField() → core::int
+    return this.{self::A::_#A#instanceField#isSet}{core::bool} ?{core::int} let final core::int? #t1 = this.{self::A::_#A#instanceField}{core::int?} in #t1{core::int} : throw new _in::LateError::fieldNI("instanceField");
+  @#C1
+  set instanceField(core::int #t2) → void {
+    this.{self::A::_#A#instanceField#isSet} = true;
+    this.{self::A::_#A#instanceField} = #t2;
+  }
+  @#C1
+  get finalInstanceField() → core::int
+    return this.{self::A::_#A#finalInstanceField#isSet}{core::bool} ?{core::int} let final core::int? #t3 = this.{self::A::_#A#finalInstanceField}{core::int?} in #t3{core::int} : throw new _in::LateError::fieldNI("finalInstanceField");
+  @#C1
+  set finalInstanceField(core::int #t4) → void
+    if(this.{self::A::_#A#finalInstanceField#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("finalInstanceField");
+    else {
+      this.{self::A::_#A#finalInstanceField#isSet} = true;
+      this.{self::A::_#A#finalInstanceField} = #t4;
+    }
+  @#C1
+  get finalInstanceFieldWithInitializer() → core::int {
+    if(!this.{self::A::_#A#finalInstanceFieldWithInitializer#isSet}{core::bool}) {
+      final core::int #t5 = 0;
+      if(this.{self::A::_#A#finalInstanceFieldWithInitializer#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("finalInstanceFieldWithInitializer");
+      this.{self::A::_#A#finalInstanceFieldWithInitializer} = #t5;
+      this.{self::A::_#A#finalInstanceFieldWithInitializer#isSet} = true;
+    }
+    return let final core::int? #t6 = this.{self::A::_#A#finalInstanceFieldWithInitializer}{core::int?} in #t6{core::int};
+  }
+  @#C1
+  get covariantInstanceField() → core::num
+    return this.{self::A::_#A#covariantInstanceField#isSet}{core::bool} ?{core::num} let final core::num? #t7 = this.{self::A::_#A#covariantInstanceField}{core::num?} in #t7{core::num} : throw new _in::LateError::fieldNI("covariantInstanceField");
+  @#C1
+  set covariantInstanceField(covariant-by-declaration core::num #t8) → void {
+    this.{self::A::_#A#covariantInstanceField#isSet} = true;
+    this.{self::A::_#A#covariantInstanceField} = #t8;
+  }
+  @#C1
+  static get staticField() → core::int
+    return self::A::_#staticField#isSet ?{core::int} let final core::int? #t9 = self::A::_#staticField in #t9{core::int} : throw new _in::LateError::fieldNI("staticField");
+  @#C1
+  static set staticField(core::int #t10) → void {
+    self::A::_#staticField#isSet = true;
+    self::A::_#staticField = #t10;
+  }
+  @#C1
+  static get finalStaticField() → core::int
+    return self::A::_#finalStaticField#isSet ?{core::int} let final core::int? #t11 = self::A::_#finalStaticField in #t11{core::int} : throw new _in::LateError::fieldNI("finalStaticField");
+  @#C1
+  static set finalStaticField(core::int #t12) → void
+    if(self::A::_#finalStaticField#isSet)
+      throw new _in::LateError::fieldAI("finalStaticField");
+    else {
+      self::A::_#finalStaticField#isSet = true;
+      self::A::_#finalStaticField = #t12;
+    }
+  @#C1
+  static get finalStaticFieldWithInitializer() → core::int {
+    if(!self::A::_#finalStaticFieldWithInitializer#isSet) {
+      final core::int #t13 = 0;
+      if(self::A::_#finalStaticFieldWithInitializer#isSet)
+        throw new _in::LateError::fieldADI("finalStaticFieldWithInitializer");
+      self::A::_#finalStaticFieldWithInitializer = #t13;
+      self::A::_#finalStaticFieldWithInitializer#isSet = true;
+    }
+    return let final core::int? #t14 = self::A::_#finalStaticFieldWithInitializer in #t14{core::int};
+  }
+}
+abstract class B extends core::Object /*isMixinDeclaration*/  {
+  field core::int? _#B#instanceField = null;
+  field core::bool _#B#instanceField#isSet = false;
+  field core::int? _#B#finalInstanceField = null;
+  field core::bool _#B#finalInstanceField#isSet = false;
+  field core::int? _#B#finalInstanceFieldWithInitializer = null;
+  field core::bool _#B#finalInstanceFieldWithInitializer#isSet = false;
+  field core::num? _#B#covariantInstanceField = null;
+  field core::bool _#B#covariantInstanceField#isSet = false;
+  static field core::int? _#staticField = null;
+  static field core::bool _#staticField#isSet = false;
+  static field core::int? _#finalStaticField = null;
+  static field core::bool _#finalStaticField#isSet = false;
+  static field core::int? _#finalStaticFieldWithInitializer = null;
+  static field core::bool _#finalStaticFieldWithInitializer#isSet = false;
+  @#C1
+  get instanceField() → core::int
+    return this.{self::B::_#B#instanceField#isSet}{core::bool} ?{core::int} let final core::int? #t15 = this.{self::B::_#B#instanceField}{core::int?} in #t15{core::int} : throw new _in::LateError::fieldNI("instanceField");
+  @#C1
+  set instanceField(core::int #t16) → void {
+    this.{self::B::_#B#instanceField#isSet} = true;
+    this.{self::B::_#B#instanceField} = #t16;
+  }
+  @#C1
+  get finalInstanceField() → core::int
+    return this.{self::B::_#B#finalInstanceField#isSet}{core::bool} ?{core::int} let final core::int? #t17 = this.{self::B::_#B#finalInstanceField}{core::int?} in #t17{core::int} : throw new _in::LateError::fieldNI("finalInstanceField");
+  @#C1
+  set finalInstanceField(core::int #t18) → void
+    if(this.{self::B::_#B#finalInstanceField#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("finalInstanceField");
+    else {
+      this.{self::B::_#B#finalInstanceField#isSet} = true;
+      this.{self::B::_#B#finalInstanceField} = #t18;
+    }
+  @#C1
+  get finalInstanceFieldWithInitializer() → core::int {
+    if(!this.{self::B::_#B#finalInstanceFieldWithInitializer#isSet}{core::bool}) {
+      final core::int #t19 = 0;
+      if(this.{self::B::_#B#finalInstanceFieldWithInitializer#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("finalInstanceFieldWithInitializer");
+      this.{self::B::_#B#finalInstanceFieldWithInitializer} = #t19;
+      this.{self::B::_#B#finalInstanceFieldWithInitializer#isSet} = true;
+    }
+    return let final core::int? #t20 = this.{self::B::_#B#finalInstanceFieldWithInitializer}{core::int?} in #t20{core::int};
+  }
+  @#C1
+  get covariantInstanceField() → core::num
+    return this.{self::B::_#B#covariantInstanceField#isSet}{core::bool} ?{core::num} let final core::num? #t21 = this.{self::B::_#B#covariantInstanceField}{core::num?} in #t21{core::num} : throw new _in::LateError::fieldNI("covariantInstanceField");
+  @#C1
+  set covariantInstanceField(covariant-by-declaration core::num #t22) → void {
+    this.{self::B::_#B#covariantInstanceField#isSet} = true;
+    this.{self::B::_#B#covariantInstanceField} = #t22;
+  }
+  @#C1
+  static get staticField() → core::int
+    return self::B::_#staticField#isSet ?{core::int} let final core::int? #t23 = self::B::_#staticField in #t23{core::int} : throw new _in::LateError::fieldNI("staticField");
+  @#C1
+  static set staticField(core::int #t24) → void {
+    self::B::_#staticField#isSet = true;
+    self::B::_#staticField = #t24;
+  }
+  @#C1
+  static get finalStaticField() → core::int
+    return self::B::_#finalStaticField#isSet ?{core::int} let final core::int? #t25 = self::B::_#finalStaticField in #t25{core::int} : throw new _in::LateError::fieldNI("finalStaticField");
+  @#C1
+  static set finalStaticField(core::int #t26) → void
+    if(self::B::_#finalStaticField#isSet)
+      throw new _in::LateError::fieldAI("finalStaticField");
+    else {
+      self::B::_#finalStaticField#isSet = true;
+      self::B::_#finalStaticField = #t26;
+    }
+  @#C1
+  static get finalStaticFieldWithInitializer() → core::int {
+    if(!self::B::_#finalStaticFieldWithInitializer#isSet) {
+      final core::int #t27 = 0;
+      if(self::B::_#finalStaticFieldWithInitializer#isSet)
+        throw new _in::LateError::fieldADI("finalStaticFieldWithInitializer");
+      self::B::_#finalStaticFieldWithInitializer = #t27;
+      self::B::_#finalStaticFieldWithInitializer#isSet = true;
+    }
+    return let final core::int? #t28 = self::B::_#finalStaticFieldWithInitializer in #t28{core::int};
+  }
+}
+extension Extension on self::A {
+  static field extensionStaticField = self::_#Extension|extensionStaticField;
+  static field extensionStaticField = self::_#Extension|extensionStaticField#isSet;
+  static get extensionStaticField = get self::Extension|extensionStaticField;
+  static set extensionStaticField = set self::Extension|extensionStaticField;
+  static field finalExtensionStaticField = self::_#Extension|finalExtensionStaticField;
+  static field finalExtensionStaticField = self::_#Extension|finalExtensionStaticField#isSet;
+  static get finalExtensionStaticField = get self::Extension|finalExtensionStaticField;
+  static set finalExtensionStaticField = set self::Extension|finalExtensionStaticField;
+  static field finalExtensionStaticFieldWithInitializer = self::_#Extension|finalExtensionStaticFieldWithInitializer;
+  static field finalExtensionStaticFieldWithInitializer = self::_#Extension|finalExtensionStaticFieldWithInitializer#isSet;
+  static get finalExtensionStaticFieldWithInitializer = get self::Extension|finalExtensionStaticFieldWithInitializer;
+}
+static field core::int? _#topLevelField = null;
+static field core::bool _#topLevelField#isSet = false;
+static field core::int? _#finalTopLevelField = null;
+static field core::bool _#finalTopLevelField#isSet = false;
+static field core::int? _#finalTopLevelFieldWithInitializer = null;
+static field core::bool _#finalTopLevelFieldWithInitializer#isSet = false;
+static field core::int? _#Extension|extensionStaticField = null;
+static field core::bool _#Extension|extensionStaticField#isSet = false;
+static field core::int? _#Extension|finalExtensionStaticField = null;
+static field core::bool _#Extension|finalExtensionStaticField#isSet = false;
+static field core::int? _#Extension|finalExtensionStaticFieldWithInitializer = null;
+static field core::bool _#Extension|finalExtensionStaticFieldWithInitializer#isSet = false;
+@#C1
+static get topLevelField() → core::int
+  return self::_#topLevelField#isSet ?{core::int} let final core::int? #t29 = self::_#topLevelField in #t29{core::int} : throw new _in::LateError::fieldNI("topLevelField");
+@#C1
+static set topLevelField(core::int #t30) → void {
+  self::_#topLevelField#isSet = true;
+  self::_#topLevelField = #t30;
+}
+@#C1
+static get finalTopLevelField() → core::int
+  return self::_#finalTopLevelField#isSet ?{core::int} let final core::int? #t31 = self::_#finalTopLevelField in #t31{core::int} : throw new _in::LateError::fieldNI("finalTopLevelField");
+@#C1
+static set finalTopLevelField(core::int #t32) → void
+  if(self::_#finalTopLevelField#isSet)
+    throw new _in::LateError::fieldAI("finalTopLevelField");
+  else {
+    self::_#finalTopLevelField#isSet = true;
+    self::_#finalTopLevelField = #t32;
+  }
+@#C1
+static get finalTopLevelFieldWithInitializer() → core::int {
+  if(!self::_#finalTopLevelFieldWithInitializer#isSet) {
+    final core::int #t33 = 0;
+    if(self::_#finalTopLevelFieldWithInitializer#isSet)
+      throw new _in::LateError::fieldADI("finalTopLevelFieldWithInitializer");
+    self::_#finalTopLevelFieldWithInitializer = #t33;
+    self::_#finalTopLevelFieldWithInitializer#isSet = true;
+  }
+  return let final core::int? #t34 = self::_#finalTopLevelFieldWithInitializer in #t34{core::int};
+}
+@#C1
+static get Extension|extensionStaticField() → core::int
+  return self::_#Extension|extensionStaticField#isSet ?{core::int} let final core::int? #t35 = self::_#Extension|extensionStaticField in #t35{core::int} : throw new _in::LateError::fieldNI("extensionStaticField");
+@#C1
+static set Extension|extensionStaticField(core::int #t36) → void {
+  self::_#Extension|extensionStaticField#isSet = true;
+  self::_#Extension|extensionStaticField = #t36;
+}
+@#C1
+static get Extension|finalExtensionStaticField() → core::int
+  return self::_#Extension|finalExtensionStaticField#isSet ?{core::int} let final core::int? #t37 = self::_#Extension|finalExtensionStaticField in #t37{core::int} : throw new _in::LateError::fieldNI("finalExtensionStaticField");
+@#C1
+static set Extension|finalExtensionStaticField(core::int #t38) → void
+  if(self::_#Extension|finalExtensionStaticField#isSet)
+    throw new _in::LateError::fieldAI("finalExtensionStaticField");
+  else {
+    self::_#Extension|finalExtensionStaticField#isSet = true;
+    self::_#Extension|finalExtensionStaticField = #t38;
+  }
+@#C1
+static get Extension|finalExtensionStaticFieldWithInitializer() → core::int {
+  if(!self::_#Extension|finalExtensionStaticFieldWithInitializer#isSet) {
+    final core::int #t39 = 0;
+    if(self::_#Extension|finalExtensionStaticFieldWithInitializer#isSet)
+      throw new _in::LateError::fieldADI("finalExtensionStaticFieldWithInitializer");
+    self::_#Extension|finalExtensionStaticFieldWithInitializer = #t39;
+    self::_#Extension|finalExtensionStaticFieldWithInitializer#isSet = true;
+  }
+  return let final core::int? #t40 = self::_#Extension|finalExtensionStaticFieldWithInitializer in #t40{core::int};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Annotation {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///late_annotations.dart:
+- Annotation. (from org-dartlang-testcase:///late_annotations.dart:6:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/late_lowering/late_field_inference.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_field_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..bb1a104
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_field_inference.dart.weak.modular.expect
@@ -0,0 +1,101 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int? _#A#nonNullableInstanceField = null;
+  field core::bool _#A#nonNullableInstanceField#isSet = false;
+  field core::int? _#A#nullableInstanceField = null;
+  field core::bool _#A#nullableInstanceField#isSet = false;
+  static field core::int? _#nonNullableStaticField = null;
+  static field core::bool _#nonNullableStaticField#isSet = false;
+  static field core::int? _#nullableStaticField = null;
+  static field core::bool _#nullableStaticField#isSet = false;
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  get nonNullableInstanceField() → core::int {
+    if(!this.{self::A::_#A#nonNullableInstanceField#isSet}{core::bool}) {
+      this.{self::A::_#A#nonNullableInstanceField} = 0;
+      this.{self::A::_#A#nonNullableInstanceField#isSet} = true;
+    }
+    return let final core::int? #t1 = this.{self::A::_#A#nonNullableInstanceField}{core::int?} in #t1{core::int};
+  }
+  set nonNullableInstanceField(core::int #t2) → void {
+    this.{self::A::_#A#nonNullableInstanceField#isSet} = true;
+    this.{self::A::_#A#nonNullableInstanceField} = #t2;
+  }
+  get nullableInstanceField() → core::int? {
+    if(!this.{self::A::_#A#nullableInstanceField#isSet}{core::bool}) {
+      this.{self::A::_#A#nullableInstanceField} = self::method();
+      this.{self::A::_#A#nullableInstanceField#isSet} = true;
+    }
+    return this.{self::A::_#A#nullableInstanceField}{core::int?};
+  }
+  set nullableInstanceField(core::int? #t3) → void {
+    this.{self::A::_#A#nullableInstanceField#isSet} = true;
+    this.{self::A::_#A#nullableInstanceField} = #t3;
+  }
+  static get nonNullableStaticField() → core::int {
+    if(!self::A::_#nonNullableStaticField#isSet) {
+      self::A::_#nonNullableStaticField = 0;
+      self::A::_#nonNullableStaticField#isSet = true;
+    }
+    return let final core::int? #t4 = self::A::_#nonNullableStaticField in #t4{core::int};
+  }
+  static set nonNullableStaticField(core::int #t5) → void {
+    self::A::_#nonNullableStaticField#isSet = true;
+    self::A::_#nonNullableStaticField = #t5;
+  }
+  static get nullableStaticField() → core::int? {
+    if(!self::A::_#nullableStaticField#isSet) {
+      self::A::_#nullableStaticField = self::method();
+      self::A::_#nullableStaticField#isSet = true;
+    }
+    return self::A::_#nullableStaticField;
+  }
+  static set nullableStaticField(core::int? #t6) → void {
+    self::A::_#nullableStaticField#isSet = true;
+    self::A::_#nullableStaticField = #t6;
+  }
+}
+class B extends self::A {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+  get nonNullableInstanceField() → core::int
+    return 0;
+  set nonNullableInstanceField(core::int value) → void {}
+  get nullableInstanceField() → core::int?
+    return 0;
+  set nullableInstanceField(core::int? value) → void {}
+}
+static field core::int? _#nonNullableTopLevelField = null;
+static field core::bool _#nonNullableTopLevelField#isSet = false;
+static field core::int? _#nullableTopLevelField = null;
+static field core::bool _#nullableTopLevelField#isSet = false;
+static method method() → core::int?
+  return null;
+static get nonNullableTopLevelField() → core::int {
+  if(!self::_#nonNullableTopLevelField#isSet) {
+    self::_#nonNullableTopLevelField = 0;
+    self::_#nonNullableTopLevelField#isSet = true;
+  }
+  return let final core::int? #t7 = self::_#nonNullableTopLevelField in #t7{core::int};
+}
+static set nonNullableTopLevelField(core::int #t8) → void {
+  self::_#nonNullableTopLevelField#isSet = true;
+  self::_#nonNullableTopLevelField = #t8;
+}
+static get nullableTopLevelField() → core::int? {
+  if(!self::_#nullableTopLevelField#isSet) {
+    self::_#nullableTopLevelField = self::method();
+    self::_#nullableTopLevelField#isSet = true;
+  }
+  return self::_#nullableTopLevelField;
+}
+static set nullableTopLevelField(core::int? #t9) → void {
+  self::_#nullableTopLevelField#isSet = true;
+  self::_#nullableTopLevelField = #t9;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/late_lowering/late_field_with_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_field_with_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..8d1c620
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_field_with_initializer.dart.weak.modular.expect
@@ -0,0 +1,163 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  static field core::int? _#lateStaticField1 = null;
+  static field core::bool _#lateStaticField1#isSet = false;
+  static field core::int? _#lateStaticField2 = null;
+  static field core::bool _#lateStaticField2#isSet = false;
+  field core::int? _#Class#lateInstanceField = null;
+  field core::bool _#Class#lateInstanceField#isSet = false;
+  final field self::Class::T% field;
+  covariant-by-class field self::Class::T? _#Class#lateGenericField1 = null;
+  field core::bool _#Class#lateGenericField1#isSet = false;
+  covariant-by-class field self::Class::T? _#Class#lateGenericField2 = null;
+  field core::bool _#Class#lateGenericField2#isSet = false;
+  constructor •(self::Class::T% field) → self::Class<self::Class::T%>
+    : self::Class::field = field, super core::Object::•()
+    ;
+  static get lateStaticField1() → core::int {
+    if(!self::Class::_#lateStaticField1#isSet) {
+      self::Class::_#lateStaticField1 = 87;
+      self::Class::_#lateStaticField1#isSet = true;
+    }
+    return let final core::int? #t1 = self::Class::_#lateStaticField1 in #t1{core::int};
+  }
+  static set lateStaticField1(core::int #t2) → void {
+    self::Class::_#lateStaticField1#isSet = true;
+    self::Class::_#lateStaticField1 = #t2;
+  }
+  static get lateStaticField2() → core::int {
+    if(!self::Class::_#lateStaticField2#isSet) {
+      self::Class::_#lateStaticField2 = 42;
+      self::Class::_#lateStaticField2#isSet = true;
+    }
+    return let final core::int? #t3 = self::Class::_#lateStaticField2 in #t3{core::int};
+  }
+  static set lateStaticField2(core::int #t4) → void {
+    self::Class::_#lateStaticField2#isSet = true;
+    self::Class::_#lateStaticField2 = #t4;
+  }
+  static method staticMethod() → dynamic {
+    self::expect(42, self::Class::lateStaticField2);
+    self::Class::lateStaticField2 = 43;
+    self::expect(43, self::Class::lateStaticField2);
+  }
+  get lateInstanceField() → core::int {
+    if(!this.{self::Class::_#Class#lateInstanceField#isSet}{core::bool}) {
+      this.{self::Class::_#Class#lateInstanceField} = 16;
+      this.{self::Class::_#Class#lateInstanceField#isSet} = true;
+    }
+    return let final core::int? #t5 = this.{self::Class::_#Class#lateInstanceField}{core::int?} in #t5{core::int};
+  }
+  set lateInstanceField(core::int #t6) → void {
+    this.{self::Class::_#Class#lateInstanceField#isSet} = true;
+    this.{self::Class::_#Class#lateInstanceField} = #t6;
+  }
+  get lateGenericField1() → self::Class::T% {
+    if(!this.{self::Class::_#Class#lateGenericField1#isSet}{core::bool}) {
+      this.{self::Class::_#Class#lateGenericField1} = this.{self::Class::field}{self::Class::T%};
+      this.{self::Class::_#Class#lateGenericField1#isSet} = true;
+    }
+    return let final self::Class::T? #t7 = this.{self::Class::_#Class#lateGenericField1}{self::Class::T?} in #t7{self::Class::T%};
+  }
+  set lateGenericField1(covariant-by-class self::Class::T% #t8) → void {
+    this.{self::Class::_#Class#lateGenericField1#isSet} = true;
+    this.{self::Class::_#Class#lateGenericField1} = #t8;
+  }
+  get lateGenericField2() → self::Class::T% {
+    if(!this.{self::Class::_#Class#lateGenericField2#isSet}{core::bool}) {
+      this.{self::Class::_#Class#lateGenericField2} = this.{self::Class::field}{self::Class::T%};
+      this.{self::Class::_#Class#lateGenericField2#isSet} = true;
+    }
+    return let final self::Class::T? #t9 = this.{self::Class::_#Class#lateGenericField2}{self::Class::T?} in #t9{self::Class::T%};
+  }
+  set lateGenericField2(covariant-by-class self::Class::T% #t10) → void {
+    this.{self::Class::_#Class#lateGenericField2#isSet} = true;
+    this.{self::Class::_#Class#lateGenericField2} = #t10;
+  }
+  method instanceMethod(covariant-by-class self::Class::T% value) → dynamic {
+    self::expect(16, this.{self::Class::lateInstanceField}{core::int});
+    this.{self::Class::lateInstanceField} = 17;
+    self::expect(17, this.{self::Class::lateInstanceField}{core::int});
+    self::expect(this.{self::Class::field}{self::Class::T%}, this.{self::Class::lateGenericField1}{self::Class::T%});
+    this.{self::Class::lateGenericField1} = value;
+    self::expect(value, this.{self::Class::lateGenericField1}{self::Class::T%});
+    this.{self::Class::lateGenericField2} = value;
+    self::expect(value, this.{self::Class::lateGenericField2}{self::Class::T%});
+  }
+}
+extension Extension<T extends core::Object? = dynamic> on self::Class<T%> {
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1;
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1#isSet;
+  static get lateExtensionField1 = get self::Extension|lateExtensionField1;
+  static set lateExtensionField1 = set self::Extension|lateExtensionField1;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2#isSet;
+  static get lateExtensionField2 = get self::Extension|lateExtensionField2;
+  static set lateExtensionField2 = set self::Extension|lateExtensionField2;
+  static method staticMethod = self::Extension|staticMethod;
+}
+static field core::int? _#lateTopLevelField1 = null;
+static field core::bool _#lateTopLevelField1#isSet = false;
+static field core::int? _#Extension|lateExtensionField1 = null;
+static field core::bool _#Extension|lateExtensionField1#isSet = false;
+static field core::int? _#Extension|lateExtensionField2 = null;
+static field core::bool _#Extension|lateExtensionField2#isSet = false;
+static get lateTopLevelField1() → core::int {
+  if(!self::_#lateTopLevelField1#isSet) {
+    self::_#lateTopLevelField1 = 123;
+    self::_#lateTopLevelField1#isSet = true;
+  }
+  return let final core::int? #t11 = self::_#lateTopLevelField1 in #t11{core::int};
+}
+static set lateTopLevelField1(core::int #t12) → void {
+  self::_#lateTopLevelField1#isSet = true;
+  self::_#lateTopLevelField1 = #t12;
+}
+static get Extension|lateExtensionField1() → core::int {
+  if(!self::_#Extension|lateExtensionField1#isSet) {
+    self::_#Extension|lateExtensionField1 = 87;
+    self::_#Extension|lateExtensionField1#isSet = true;
+  }
+  return let final core::int? #t13 = self::_#Extension|lateExtensionField1 in #t13{core::int};
+}
+static set Extension|lateExtensionField1(core::int #t14) → void {
+  self::_#Extension|lateExtensionField1#isSet = true;
+  self::_#Extension|lateExtensionField1 = #t14;
+}
+static get Extension|lateExtensionField2() → core::int {
+  if(!self::_#Extension|lateExtensionField2#isSet) {
+    self::_#Extension|lateExtensionField2 = 42;
+    self::_#Extension|lateExtensionField2#isSet = true;
+  }
+  return let final core::int? #t15 = self::_#Extension|lateExtensionField2 in #t15{core::int};
+}
+static set Extension|lateExtensionField2(core::int #t16) → void {
+  self::_#Extension|lateExtensionField2#isSet = true;
+  self::_#Extension|lateExtensionField2 = #t16;
+}
+static method Extension|staticMethod() → dynamic {
+  self::expect(42, self::Extension|lateExtensionField2);
+  self::Extension|lateExtensionField2 = 43;
+  self::expect(43, self::Extension|lateExtensionField2);
+}
+static method main() → dynamic {
+  self::expect(123, self::lateTopLevelField1);
+  self::lateTopLevelField1 = 124;
+  self::expect(124, self::lateTopLevelField1);
+  self::expect(87, self::Class::lateStaticField1);
+  self::Class::lateStaticField1 = 88;
+  self::expect(88, self::Class::lateStaticField1);
+  self::Class::staticMethod();
+  new self::Class::•<core::int>(0).{self::Class::instanceMethod}(42){(core::int) → dynamic};
+  self::expect(87, self::Extension|lateExtensionField1);
+  self::Extension|lateExtensionField1 = 88;
+  self::expect(88, self::Extension|lateExtensionField1);
+  self::Extension|staticMethod();
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_field_without_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_field_without_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..9734ddb
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_field_without_initializer.dart.weak.modular.expect
@@ -0,0 +1,131 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  static field core::int? _#lateStaticField1 = null;
+  static field core::bool _#lateStaticField1#isSet = false;
+  static field core::int? _#lateStaticField2 = null;
+  static field core::bool _#lateStaticField2#isSet = false;
+  field core::int? _#Class#lateInstanceField = null;
+  field core::bool _#Class#lateInstanceField#isSet = false;
+  covariant-by-class field self::Class::T? _#Class#lateGenericInstanceField = null;
+  field core::bool _#Class#lateGenericInstanceField#isSet = false;
+  synthetic constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  static get lateStaticField1() → core::int
+    return self::Class::_#lateStaticField1#isSet ?{core::int} let final core::int? #t1 = self::Class::_#lateStaticField1 in #t1{core::int} : throw new _in::LateError::fieldNI("lateStaticField1");
+  static set lateStaticField1(core::int #t2) → void {
+    self::Class::_#lateStaticField1#isSet = true;
+    self::Class::_#lateStaticField1 = #t2;
+  }
+  static get lateStaticField2() → core::int
+    return self::Class::_#lateStaticField2#isSet ?{core::int} let final core::int? #t3 = self::Class::_#lateStaticField2 in #t3{core::int} : throw new _in::LateError::fieldNI("lateStaticField2");
+  static set lateStaticField2(core::int #t4) → void {
+    self::Class::_#lateStaticField2#isSet = true;
+    self::Class::_#lateStaticField2 = #t4;
+  }
+  static method staticMethod() → dynamic {
+    self::throws(() → core::int => self::Class::lateStaticField2, "Read value from uninitialized Class.lateStaticField2");
+    self::Class::lateStaticField2 = 42;
+    self::expect(42, self::Class::lateStaticField2);
+  }
+  get lateInstanceField() → core::int
+    return this.{self::Class::_#Class#lateInstanceField#isSet}{core::bool} ?{core::int} let final core::int? #t5 = this.{self::Class::_#Class#lateInstanceField}{core::int?} in #t5{core::int} : throw new _in::LateError::fieldNI("lateInstanceField");
+  set lateInstanceField(core::int #t6) → void {
+    this.{self::Class::_#Class#lateInstanceField#isSet} = true;
+    this.{self::Class::_#Class#lateInstanceField} = #t6;
+  }
+  get lateGenericInstanceField() → self::Class::T%
+    return this.{self::Class::_#Class#lateGenericInstanceField#isSet}{core::bool} ?{self::Class::T%} let final self::Class::T? #t7 = this.{self::Class::_#Class#lateGenericInstanceField}{self::Class::T?} in #t7{self::Class::T%} : throw new _in::LateError::fieldNI("lateGenericInstanceField");
+  set lateGenericInstanceField(covariant-by-class self::Class::T% #t8) → void {
+    this.{self::Class::_#Class#lateGenericInstanceField#isSet} = true;
+    this.{self::Class::_#Class#lateGenericInstanceField} = #t8;
+  }
+  method instanceMethod(covariant-by-class self::Class::T% value) → dynamic {
+    self::throws(() → core::int => this.{self::Class::lateInstanceField}{core::int}, "Read value from uninitialized Class.lateInstanceField");
+    this.{self::Class::lateInstanceField} = 16;
+    self::expect(16, this.{self::Class::lateInstanceField}{core::int});
+    self::throws(() → self::Class::T% => this.{self::Class::lateGenericInstanceField}{self::Class::T%}, "Read value from uninitialized Class.lateGenericInstanceField");
+    this.{self::Class::lateGenericInstanceField} = value;
+    self::expect(value, this.{self::Class::lateGenericInstanceField}{self::Class::T%});
+  }
+}
+extension Extension<T extends core::Object? = dynamic> on self::Class<T%> {
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1;
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1#isSet;
+  static get lateExtensionField1 = get self::Extension|lateExtensionField1;
+  static set lateExtensionField1 = set self::Extension|lateExtensionField1;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2#isSet;
+  static get lateExtensionField2 = get self::Extension|lateExtensionField2;
+  static set lateExtensionField2 = set self::Extension|lateExtensionField2;
+  static method staticMethod = self::Extension|staticMethod;
+}
+static field core::int? _#lateTopLevelField = null;
+static field core::bool _#lateTopLevelField#isSet = false;
+static field core::int? _#Extension|lateExtensionField1 = null;
+static field core::bool _#Extension|lateExtensionField1#isSet = false;
+static field core::int? _#Extension|lateExtensionField2 = null;
+static field core::bool _#Extension|lateExtensionField2#isSet = false;
+static get lateTopLevelField() → core::int
+  return self::_#lateTopLevelField#isSet ?{core::int} let final core::int? #t9 = self::_#lateTopLevelField in #t9{core::int} : throw new _in::LateError::fieldNI("lateTopLevelField");
+static set lateTopLevelField(core::int #t10) → void {
+  self::_#lateTopLevelField#isSet = true;
+  self::_#lateTopLevelField = #t10;
+}
+static get Extension|lateExtensionField1() → core::int
+  return self::_#Extension|lateExtensionField1#isSet ?{core::int} let final core::int? #t11 = self::_#Extension|lateExtensionField1 in #t11{core::int} : throw new _in::LateError::fieldNI("lateExtensionField1");
+static set Extension|lateExtensionField1(core::int #t12) → void {
+  self::_#Extension|lateExtensionField1#isSet = true;
+  self::_#Extension|lateExtensionField1 = #t12;
+}
+static get Extension|lateExtensionField2() → core::int
+  return self::_#Extension|lateExtensionField2#isSet ?{core::int} let final core::int? #t13 = self::_#Extension|lateExtensionField2 in #t13{core::int} : throw new _in::LateError::fieldNI("lateExtensionField2");
+static set Extension|lateExtensionField2(core::int #t14) → void {
+  self::_#Extension|lateExtensionField2#isSet = true;
+  self::_#Extension|lateExtensionField2 = #t14;
+}
+static method Extension|staticMethod() → dynamic {
+  self::throws(() → core::int => self::Extension|lateExtensionField2, "Read value from uninitialized Class.lateExtensionField2");
+  self::Extension|lateExtensionField2 = 42;
+  self::expect(42, self::Extension|lateExtensionField2);
+}
+static method main() → dynamic {
+  self::throws(() → core::int => self::lateTopLevelField, "Read value from uninitialized lateTopLevelField");
+  self::lateTopLevelField = 123;
+  self::expect(123, self::lateTopLevelField);
+  self::throws(() → core::int => self::Class::lateStaticField1, "Read value from uninitialized Class.lateStaticField1");
+  self::Class::lateStaticField1 = 87;
+  self::expect(87, self::Class::lateStaticField1);
+  self::Class::staticMethod();
+  new self::Class::•<core::int>().{self::Class::instanceMethod}(0){(core::int) → dynamic};
+  self::Class<core::int> c = new self::Class::•<core::int>();
+  self::throws(() → core::int => c.{self::Class::lateInstanceField}{core::int}, "Read value from uninitialized Class.lateInstanceField");
+  c.{self::Class::lateInstanceField} = 16;
+  self::expect(16, c.{self::Class::lateInstanceField}{core::int});
+  self::throws(() → core::int => c.{self::Class::lateGenericInstanceField}{core::int}, "Read value from uninitialized Class.lateGenericInstanceField");
+  c.{self::Class::lateGenericInstanceField} = 0;
+  self::expect(0, c.{self::Class::lateGenericInstanceField}{core::int});
+  self::throws(() → core::int => self::Extension|lateExtensionField1, "Read value from uninitialized Extension.lateExtensionField1");
+  self::Extension|lateExtensionField1 = 87;
+  self::expect(87, self::Extension|lateExtensionField1);
+  self::Extension|staticMethod();
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_final_field_with_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_final_field_with_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..35715d5
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_final_field_with_initializer.dart.weak.modular.expect
@@ -0,0 +1,198 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class B extends core::Object {
+  final field core::int x;
+  constructor •(core::int x) → self::B
+    : self::B::x = x, super core::Object::•()
+    ;
+}
+class C extends self::B {
+  field core::int? _#C#y = null;
+  field core::bool _#C#y#isSet = false;
+  constructor •(core::int x) → self::C
+    : super self::B::•(x)
+    ;
+  get y() → core::int {
+    if(!this.{self::C::_#C#y#isSet}{core::bool}) {
+      final core::int #t1 = this.{self::B::x}{core::int}.{core::num::+}(1){(core::num) → core::int};
+      if(this.{self::C::_#C#y#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("y");
+      this.{self::C::_#C#y} = #t1;
+      this.{self::C::_#C#y#isSet} = true;
+    }
+    return let final core::int? #t2 = this.{self::C::_#C#y}{core::int?} in #t2{core::int};
+  }
+  method method() → dynamic
+    return this.{self::B::x}{core::int};
+}
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  static field core::int? lateStaticField1Init = null;
+  static field core::int? _#lateStaticField1 = null;
+  static field core::bool _#lateStaticField1#isSet = false;
+  static field core::int? lateStaticField2Init = null;
+  static field core::int? _#lateStaticField2 = null;
+  static field core::bool _#lateStaticField2#isSet = false;
+  field core::int? lateInstanceFieldInit = null;
+  field core::int? _#Class#lateInstanceField = null;
+  field core::bool _#Class#lateInstanceField#isSet = false;
+  covariant-by-class field self::Class::T? lateGenericFieldInit = null;
+  final field self::Class::T% field;
+  field self::Class::T? _#Class#lateGenericField = null;
+  field core::bool _#Class#lateGenericField#isSet = false;
+  constructor •(self::Class::T% field) → self::Class<self::Class::T%>
+    : self::Class::field = field, super core::Object::•()
+    ;
+  static method initLateStaticField1(core::int value) → core::int {
+    return self::Class::lateStaticField1Init = value;
+  }
+  static get lateStaticField1() → core::int {
+    if(!self::Class::_#lateStaticField1#isSet) {
+      final core::int #t3 = self::Class::initLateStaticField1(87);
+      if(self::Class::_#lateStaticField1#isSet)
+        throw new _in::LateError::fieldADI("lateStaticField1");
+      self::Class::_#lateStaticField1 = #t3;
+      self::Class::_#lateStaticField1#isSet = true;
+    }
+    return let final core::int? #t4 = self::Class::_#lateStaticField1 in #t4{core::int};
+  }
+  static method initLateStaticField2(core::int value) → core::int {
+    return self::Class::lateStaticField2Init = value;
+  }
+  static get lateStaticField2() → core::int {
+    if(!self::Class::_#lateStaticField2#isSet) {
+      final core::int #t5 = self::Class::initLateStaticField2(42);
+      if(self::Class::_#lateStaticField2#isSet)
+        throw new _in::LateError::fieldADI("lateStaticField2");
+      self::Class::_#lateStaticField2 = #t5;
+      self::Class::_#lateStaticField2#isSet = true;
+    }
+    return let final core::int? #t6 = self::Class::_#lateStaticField2 in #t6{core::int};
+  }
+  static method staticMethod() → dynamic {
+    self::expect(null, self::Class::lateStaticField2Init);
+    self::expect(42, self::Class::lateStaticField2);
+    self::expect(42, self::Class::lateStaticField2Init);
+  }
+  method initLateInstanceField(core::int value) → core::int {
+    return this.{self::Class::lateInstanceFieldInit} = value;
+  }
+  get lateInstanceField() → core::int {
+    if(!this.{self::Class::_#Class#lateInstanceField#isSet}{core::bool}) {
+      final core::int #t7 = this.{self::Class::initLateInstanceField}(16){(core::int) → core::int};
+      if(this.{self::Class::_#Class#lateInstanceField#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("lateInstanceField");
+      this.{self::Class::_#Class#lateInstanceField} = #t7;
+      this.{self::Class::_#Class#lateInstanceField#isSet} = true;
+    }
+    return let final core::int? #t8 = this.{self::Class::_#Class#lateInstanceField}{core::int?} in #t8{core::int};
+  }
+  method initLateGenericField(covariant-by-class self::Class::T% value) → self::Class::T% {
+    return this.{self::Class::lateGenericFieldInit} = value;
+  }
+  get lateGenericField() → self::Class::T% {
+    if(!this.{self::Class::_#Class#lateGenericField#isSet}{core::bool}) {
+      final self::Class::T% #t9 = this.{self::Class::initLateGenericField}(this.{self::Class::field}{self::Class::T%}){(self::Class::T%) → self::Class::T%};
+      if(this.{self::Class::_#Class#lateGenericField#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("lateGenericField");
+      this.{self::Class::_#Class#lateGenericField} = #t9;
+      this.{self::Class::_#Class#lateGenericField#isSet} = true;
+    }
+    return let final self::Class::T? #t10 = this.{self::Class::_#Class#lateGenericField}{self::Class::T?} in #t10{self::Class::T%};
+  }
+  method instanceMethod() → dynamic {
+    self::expect(null, this.{self::Class::lateInstanceFieldInit}{core::int?});
+    self::expect(16, this.{self::Class::lateInstanceField}{core::int});
+    self::expect(16, this.{self::Class::lateInstanceFieldInit}{core::int?});
+    self::expect(null, this.{self::Class::lateGenericFieldInit}{self::Class::T?});
+    self::expect(this.{self::Class::field}{self::Class::T%}, this.{self::Class::lateGenericField}{self::Class::T%});
+    self::expect(this.{self::Class::field}{self::Class::T%}, this.{self::Class::lateGenericFieldInit}{self::Class::T?});
+  }
+}
+extension Extension<T extends core::Object? = dynamic> on self::Class<T%> {
+  static field lateExtensionField1Init = self::Extension|lateExtensionField1Init;
+  static method initLateExtensionField1 = self::Extension|initLateExtensionField1;
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1;
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1#isSet;
+  static get lateExtensionField1 = get self::Extension|lateExtensionField1;
+  static field lateExtensionField2Init = self::Extension|lateExtensionField2Init;
+  static method initLateExtensionField2 = self::Extension|initLateExtensionField2;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2#isSet;
+  static get lateExtensionField2 = get self::Extension|lateExtensionField2;
+  static method staticMethod = self::Extension|staticMethod;
+}
+static field core::int? lateTopLevelField1Init;
+static field core::int? _#lateTopLevelField1 = null;
+static field core::bool _#lateTopLevelField1#isSet = false;
+static field core::int? Extension|lateExtensionField1Init;
+static field core::int? _#Extension|lateExtensionField1 = null;
+static field core::bool _#Extension|lateExtensionField1#isSet = false;
+static field core::int? Extension|lateExtensionField2Init;
+static field core::int? _#Extension|lateExtensionField2 = null;
+static field core::bool _#Extension|lateExtensionField2#isSet = false;
+static method initLateTopLevelField1(core::int value) → core::int {
+  return self::lateTopLevelField1Init = value;
+}
+static get lateTopLevelField1() → core::int {
+  if(!self::_#lateTopLevelField1#isSet) {
+    final core::int #t11 = self::initLateTopLevelField1(123);
+    if(self::_#lateTopLevelField1#isSet)
+      throw new _in::LateError::fieldADI("lateTopLevelField1");
+    self::_#lateTopLevelField1 = #t11;
+    self::_#lateTopLevelField1#isSet = true;
+  }
+  return let final core::int? #t12 = self::_#lateTopLevelField1 in #t12{core::int};
+}
+static method Extension|initLateExtensionField1(core::int value) → core::int {
+  return self::Extension|lateExtensionField1Init = value;
+}
+static get Extension|lateExtensionField1() → core::int {
+  if(!self::_#Extension|lateExtensionField1#isSet) {
+    final core::int #t13 = self::Extension|initLateExtensionField1(87);
+    if(self::_#Extension|lateExtensionField1#isSet)
+      throw new _in::LateError::fieldADI("lateExtensionField1");
+    self::_#Extension|lateExtensionField1 = #t13;
+    self::_#Extension|lateExtensionField1#isSet = true;
+  }
+  return let final core::int? #t14 = self::_#Extension|lateExtensionField1 in #t14{core::int};
+}
+static method Extension|initLateExtensionField2(core::int value) → core::int {
+  return self::Extension|lateExtensionField2Init = value;
+}
+static get Extension|lateExtensionField2() → core::int {
+  if(!self::_#Extension|lateExtensionField2#isSet) {
+    final core::int #t15 = self::Extension|initLateExtensionField2(42);
+    if(self::_#Extension|lateExtensionField2#isSet)
+      throw new _in::LateError::fieldADI("lateExtensionField2");
+    self::_#Extension|lateExtensionField2 = #t15;
+    self::_#Extension|lateExtensionField2#isSet = true;
+  }
+  return let final core::int? #t16 = self::_#Extension|lateExtensionField2 in #t16{core::int};
+}
+static method Extension|staticMethod() → dynamic {
+  self::expect(null, self::Extension|lateExtensionField2Init);
+  self::expect(42, self::Extension|lateExtensionField2);
+  self::expect(42, self::Extension|lateExtensionField2Init);
+}
+static method main() → dynamic {
+  self::expect(null, self::lateTopLevelField1Init);
+  self::expect(123, self::lateTopLevelField1);
+  self::expect(123, self::lateTopLevelField1Init);
+  self::expect(null, self::Class::lateStaticField1Init);
+  self::expect(87, self::Class::lateStaticField1);
+  self::expect(87, self::Class::lateStaticField1Init);
+  self::Class::staticMethod();
+  new self::Class::•<core::int>(0).{self::Class::instanceMethod}(){() → dynamic};
+  self::expect(null, self::Extension|lateExtensionField1Init);
+  self::expect(87, self::Extension|lateExtensionField1);
+  self::expect(87, self::Extension|lateExtensionField1Init);
+  self::Extension|staticMethod();
+  self::expect(2, new self::C::•(1).{self::C::y}{core::int});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_final_field_without_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_final_field_without_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..f0429db
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_final_field_without_initializer.dart.weak.modular.expect
@@ -0,0 +1,137 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class extends core::Object {
+  static field core::int? _#lateStaticField1 = null;
+  static field core::bool _#lateStaticField1#isSet = false;
+  static field core::int? _#lateStaticField2 = null;
+  static field core::bool _#lateStaticField2#isSet = false;
+  field core::int? _#Class#lateInstanceField = null;
+  field core::bool _#Class#lateInstanceField#isSet = false;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  static get lateStaticField1() → core::int
+    return self::Class::_#lateStaticField1#isSet ?{core::int} let final core::int? #t1 = self::Class::_#lateStaticField1 in #t1{core::int} : throw new _in::LateError::fieldNI("lateStaticField1");
+  static set lateStaticField1(core::int #t2) → void
+    if(self::Class::_#lateStaticField1#isSet)
+      throw new _in::LateError::fieldAI("lateStaticField1");
+    else {
+      self::Class::_#lateStaticField1#isSet = true;
+      self::Class::_#lateStaticField1 = #t2;
+    }
+  static get lateStaticField2() → core::int
+    return self::Class::_#lateStaticField2#isSet ?{core::int} let final core::int? #t3 = self::Class::_#lateStaticField2 in #t3{core::int} : throw new _in::LateError::fieldNI("lateStaticField2");
+  static set lateStaticField2(core::int #t4) → void
+    if(self::Class::_#lateStaticField2#isSet)
+      throw new _in::LateError::fieldAI("lateStaticField2");
+    else {
+      self::Class::_#lateStaticField2#isSet = true;
+      self::Class::_#lateStaticField2 = #t4;
+    }
+  static method staticMethod() → dynamic {
+    self::throws(() → core::int => self::Class::lateStaticField2, "Read value from uninitialized Class.lateStaticField2");
+    self::Class::lateStaticField2 = 42;
+    self::expect(42, self::Class::lateStaticField2);
+    self::throws(() → core::int => self::Class::lateStaticField2 = 43, "Write value to initialized Class.lateStaticField2");
+  }
+  get lateInstanceField() → core::int
+    return this.{self::Class::_#Class#lateInstanceField#isSet}{core::bool} ?{core::int} let final core::int? #t5 = this.{self::Class::_#Class#lateInstanceField}{core::int?} in #t5{core::int} : throw new _in::LateError::fieldNI("lateInstanceField");
+  set lateInstanceField(core::int #t6) → void
+    if(this.{self::Class::_#Class#lateInstanceField#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("lateInstanceField");
+    else {
+      this.{self::Class::_#Class#lateInstanceField#isSet} = true;
+      this.{self::Class::_#Class#lateInstanceField} = #t6;
+    }
+  method instanceMethod() → dynamic {
+    self::throws(() → core::int => this.{self::Class::lateInstanceField}{core::int}, "Read value from uninitialized Class.lateInstanceField");
+    this.{self::Class::lateInstanceField} = 16;
+    self::expect(16, this.{self::Class::lateInstanceField}{core::int});
+    self::throws(() → core::int => this.{self::Class::lateInstanceField} = 17, "Write value to initialized Class.lateInstanceField");
+  }
+}
+extension Extension on self::Class {
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1;
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1#isSet;
+  static get lateExtensionField1 = get self::Extension|lateExtensionField1;
+  static set lateExtensionField1 = set self::Extension|lateExtensionField1;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2#isSet;
+  static get lateExtensionField2 = get self::Extension|lateExtensionField2;
+  static set lateExtensionField2 = set self::Extension|lateExtensionField2;
+  static method staticMethod = self::Extension|staticMethod;
+}
+static field core::int? _#lateTopLevelField = null;
+static field core::bool _#lateTopLevelField#isSet = false;
+static field core::int? _#Extension|lateExtensionField1 = null;
+static field core::bool _#Extension|lateExtensionField1#isSet = false;
+static field core::int? _#Extension|lateExtensionField2 = null;
+static field core::bool _#Extension|lateExtensionField2#isSet = false;
+static get lateTopLevelField() → core::int
+  return self::_#lateTopLevelField#isSet ?{core::int} let final core::int? #t7 = self::_#lateTopLevelField in #t7{core::int} : throw new _in::LateError::fieldNI("lateTopLevelField");
+static set lateTopLevelField(core::int #t8) → void
+  if(self::_#lateTopLevelField#isSet)
+    throw new _in::LateError::fieldAI("lateTopLevelField");
+  else {
+    self::_#lateTopLevelField#isSet = true;
+    self::_#lateTopLevelField = #t8;
+  }
+static get Extension|lateExtensionField1() → core::int
+  return self::_#Extension|lateExtensionField1#isSet ?{core::int} let final core::int? #t9 = self::_#Extension|lateExtensionField1 in #t9{core::int} : throw new _in::LateError::fieldNI("lateExtensionField1");
+static set Extension|lateExtensionField1(core::int #t10) → void
+  if(self::_#Extension|lateExtensionField1#isSet)
+    throw new _in::LateError::fieldAI("lateExtensionField1");
+  else {
+    self::_#Extension|lateExtensionField1#isSet = true;
+    self::_#Extension|lateExtensionField1 = #t10;
+  }
+static get Extension|lateExtensionField2() → core::int
+  return self::_#Extension|lateExtensionField2#isSet ?{core::int} let final core::int? #t11 = self::_#Extension|lateExtensionField2 in #t11{core::int} : throw new _in::LateError::fieldNI("lateExtensionField2");
+static set Extension|lateExtensionField2(core::int #t12) → void
+  if(self::_#Extension|lateExtensionField2#isSet)
+    throw new _in::LateError::fieldAI("lateExtensionField2");
+  else {
+    self::_#Extension|lateExtensionField2#isSet = true;
+    self::_#Extension|lateExtensionField2 = #t12;
+  }
+static method Extension|staticMethod() → dynamic {
+  self::throws(() → core::int => self::Extension|lateExtensionField2, "Read value from uninitialized Class.lateExtensionField2");
+  self::Extension|lateExtensionField2 = 42;
+  self::expect(42, self::Extension|lateExtensionField2);
+  self::throws(() → core::int => self::Extension|lateExtensionField2 = 43, "Write value to initialized Class.lateExtensionField2");
+}
+static method main() → dynamic {
+  self::throws(() → core::int => self::lateTopLevelField, "Read value from uninitialized lateTopLevelField");
+  self::lateTopLevelField = 123;
+  self::expect(123, self::lateTopLevelField);
+  self::throws(() → core::int => self::lateTopLevelField = 124, "Write value to initialized lateTopLevelField");
+  self::throws(() → core::int => self::Class::lateStaticField1, "Read value from uninitialized Class.lateStaticField1");
+  self::Class::lateStaticField1 = 87;
+  self::expect(87, self::Class::lateStaticField1);
+  self::throws(() → core::int => self::Class::lateStaticField1 = 88, "Write value to initialized Class.lateStaticField1");
+  self::Class::staticMethod();
+  new self::Class::•().{self::Class::instanceMethod}(){() → dynamic};
+  self::throws(() → core::int => self::Extension|lateExtensionField1, "Read value from uninitialized Extension.lateExtensionField1");
+  self::Extension|lateExtensionField1 = 87;
+  self::expect(87, self::Extension|lateExtensionField1);
+  self::throws(() → core::int => self::Extension|lateExtensionField1 = 88, "Write value to initialized Extension.lateExtensionField1");
+  self::Extension|staticMethod();
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_final_local_with_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_final_local_with_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..49e5b26
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_final_local_with_initializer.dart.weak.modular.expect
@@ -0,0 +1,54 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+static method main() → dynamic {
+  core::int? lateLocalInit;
+  function initLateLocal(core::int value) → core::int {
+    return lateLocalInit = value;
+  }
+  lowered final core::int? #lateLocal;
+  lowered core::bool #lateLocal#isSet = false;
+  function #lateLocal#get() → core::int {
+    if(!#lateLocal#isSet) {
+      final core::int #t1 = initLateLocal(123){(core::int) → core::int};
+      if(#lateLocal#isSet)
+        throw new _in::LateError::localADI("lateLocal");
+      #lateLocal = #t1;
+      #lateLocal#isSet = true;
+    }
+    return #lateLocal{core::int};
+  }
+  self::expect(null, lateLocalInit);
+  self::expect(123, #lateLocal#get(){() → core::int});
+  self::expect(123, lateLocalInit);
+  function local<T extends core::Object? = dynamic>(T% value) → Null {
+    T? lateGenericLocalInit;
+    function initLateGenericLocal(T% value) → T% {
+      return lateGenericLocalInit = value;
+    }
+    lowered final T? #lateGenericLocal;
+    lowered core::bool #lateGenericLocal#isSet = false;
+    function #lateGenericLocal#get() → T% {
+      if(!#lateGenericLocal#isSet) {
+        final T% #t2 = initLateGenericLocal(value){(T%) → T%};
+        if(#lateGenericLocal#isSet)
+          throw new _in::LateError::localADI("lateGenericLocal");
+        #lateGenericLocal = #t2;
+        #lateGenericLocal#isSet = true;
+      }
+      return #lateGenericLocal{T%};
+    }
+    self::expect(null, lateGenericLocalInit);
+    self::expect(value, #lateGenericLocal#get(){() → T%});
+    self::expect(value, lateGenericLocalInit);
+  }
+  local<core::int?>(null){(core::int?) → Null};
+  local<core::int?>(42){(core::int?) → Null};
+  local<core::int>(42){(core::int) → Null};
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_final_local_without_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_final_local_without_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..6050d9e
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_final_local_without_initializer.dart.weak.modular.expect
@@ -0,0 +1,68 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+static method main() → dynamic {
+  core::bool b = (() → core::bool => false)(){() → core::bool};
+  lowered final core::int? #lateLocal;
+  lowered core::bool #lateLocal#isSet = false;
+  function #lateLocal#get() → core::int
+    return #lateLocal#isSet ?{core::int} #lateLocal{core::int} : throw new _in::LateError::localNI("lateLocal");
+  function #lateLocal#set(core::int #t1) → dynamic
+    if(#lateLocal#isSet)
+      throw new _in::LateError::localAI("lateLocal");
+    else {
+      #lateLocal#isSet = true;
+      return #lateLocal = #t1;
+    }
+  if(b) {
+    #lateLocal#set(123){(core::int) → dynamic};
+  }
+  self::throws(() → core::int => #lateLocal#get(){() → core::int}, "Read value from uninitialized lateLocal");
+  if(!b) {
+    self::expect(123, #lateLocal#set(123){(core::int) → dynamic});
+    self::expect(123, #lateLocal#get(){() → core::int});
+  }
+  self::throws(() → core::int => #lateLocal#set(124){(core::int) → dynamic}, "Write value to initialized lateLocal");
+  function local<T extends core::Object? = dynamic>(T% value) → Null {
+    lowered final T? #lateGenericLocal;
+    lowered core::bool #lateGenericLocal#isSet = false;
+    function #lateGenericLocal#get() → T%
+      return #lateGenericLocal#isSet ?{T%} #lateGenericLocal{T%} : throw new _in::LateError::localNI("lateGenericLocal");
+    function #lateGenericLocal#set(T% #t2) → dynamic
+      if(#lateGenericLocal#isSet)
+        throw new _in::LateError::localAI("lateGenericLocal");
+      else {
+        #lateGenericLocal#isSet = true;
+        return #lateGenericLocal = #t2;
+      }
+    if(b) {
+      #lateGenericLocal#set(value){(T%) → dynamic};
+    }
+    self::throws(() → T% => #lateGenericLocal#get(){() → T%}, "Read value from uninitialized lateGenericLocal");
+    if(!b) {
+      self::expect(value, #lateGenericLocal#set(value){(T%) → dynamic});
+      self::expect(value, #lateGenericLocal#get(){() → T%});
+    }
+    self::throws(() → T% => #lateGenericLocal#set(value){(T%) → dynamic}, "Write value to initialized lateGenericLocal");
+  }
+  local<core::int?>(null){(core::int?) → Null};
+  local<core::int?>(42){(core::int?) → Null};
+  local<core::int>(42){(core::int) → Null};
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_final_nullable_field_with_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_final_nullable_field_with_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..0b29db8
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_final_nullable_field_with_initializer.dart.weak.modular.expect
@@ -0,0 +1,174 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  static field core::int? lateStaticField1Init = null;
+  static field core::int? _#lateStaticField1 = null;
+  static field core::bool _#lateStaticField1#isSet = false;
+  static field core::int? lateStaticField2Init = null;
+  static field core::int? _#lateStaticField2 = null;
+  static field core::bool _#lateStaticField2#isSet = false;
+  field core::int? lateInstanceFieldInit = null;
+  field core::int? _#Class#lateInstanceField = null;
+  field core::bool _#Class#lateInstanceField#isSet = false;
+  covariant-by-class field self::Class::T? lateGenericInstanceFieldInit = null;
+  final field self::Class::T? field;
+  field self::Class::T? _#Class#lateGenericInstanceField = null;
+  field core::bool _#Class#lateGenericInstanceField#isSet = false;
+  constructor •(self::Class::T? field) → self::Class<self::Class::T%>
+    : self::Class::field = field, super core::Object::•()
+    ;
+  static method initLateStaticField1(core::int value) → core::int? {
+    return self::Class::lateStaticField1Init = value;
+  }
+  static get lateStaticField1() → core::int? {
+    if(!self::Class::_#lateStaticField1#isSet) {
+      final core::int? #t1 = self::Class::initLateStaticField1(87);
+      if(self::Class::_#lateStaticField1#isSet)
+        throw new _in::LateError::fieldADI("lateStaticField1");
+      self::Class::_#lateStaticField1 = #t1;
+      self::Class::_#lateStaticField1#isSet = true;
+    }
+    return self::Class::_#lateStaticField1;
+  }
+  static method initLateStaticField2(core::int value) → core::int? {
+    return self::Class::lateStaticField2Init = value;
+  }
+  static get lateStaticField2() → core::int? {
+    if(!self::Class::_#lateStaticField2#isSet) {
+      final core::int? #t2 = self::Class::initLateStaticField2(42);
+      if(self::Class::_#lateStaticField2#isSet)
+        throw new _in::LateError::fieldADI("lateStaticField2");
+      self::Class::_#lateStaticField2 = #t2;
+      self::Class::_#lateStaticField2#isSet = true;
+    }
+    return self::Class::_#lateStaticField2;
+  }
+  static method staticMethod() → dynamic {
+    self::expect(null, self::Class::lateStaticField2Init);
+    self::expect(42, self::Class::lateStaticField2);
+    self::expect(42, self::Class::lateStaticField2Init);
+  }
+  method initLateInstanceField(core::int value) → core::int? {
+    return this.{self::Class::lateInstanceFieldInit} = value;
+  }
+  get lateInstanceField() → core::int? {
+    if(!this.{self::Class::_#Class#lateInstanceField#isSet}{core::bool}) {
+      final core::int? #t3 = this.{self::Class::initLateInstanceField}(16){(core::int) → core::int?};
+      if(this.{self::Class::_#Class#lateInstanceField#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("lateInstanceField");
+      this.{self::Class::_#Class#lateInstanceField} = #t3;
+      this.{self::Class::_#Class#lateInstanceField#isSet} = true;
+    }
+    return this.{self::Class::_#Class#lateInstanceField}{core::int?};
+  }
+  method initLateGenericInstanceField(covariant-by-class self::Class::T? value) → self::Class::T? {
+    return this.{self::Class::lateGenericInstanceFieldInit} = value;
+  }
+  get lateGenericInstanceField() → self::Class::T? {
+    if(!this.{self::Class::_#Class#lateGenericInstanceField#isSet}{core::bool}) {
+      final self::Class::T? #t4 = this.{self::Class::initLateGenericInstanceField}(this.{self::Class::field}{self::Class::T?}){(self::Class::T?) → self::Class::T?};
+      if(this.{self::Class::_#Class#lateGenericInstanceField#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("lateGenericInstanceField");
+      this.{self::Class::_#Class#lateGenericInstanceField} = #t4;
+      this.{self::Class::_#Class#lateGenericInstanceField#isSet} = true;
+    }
+    return this.{self::Class::_#Class#lateGenericInstanceField}{self::Class::T?};
+  }
+  method instanceMethod() → dynamic {
+    self::expect(null, this.{self::Class::lateInstanceFieldInit}{core::int?});
+    self::expect(16, this.{self::Class::lateInstanceField}{core::int?});
+    self::expect(16, this.{self::Class::lateInstanceFieldInit}{core::int?});
+    self::expect(null, this.{self::Class::lateGenericInstanceFieldInit}{self::Class::T?});
+    self::expect(this.{self::Class::field}{self::Class::T?}, this.{self::Class::lateGenericInstanceField}{self::Class::T?});
+    self::expect(this.{self::Class::field}{self::Class::T?}, this.{self::Class::lateGenericInstanceFieldInit}{self::Class::T?});
+  }
+}
+extension Extension<T extends core::Object? = dynamic> on self::Class<T%> {
+  static field lateExtensionField1Init = self::Extension|lateExtensionField1Init;
+  static method initLateExtensionField1 = self::Extension|initLateExtensionField1;
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1;
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1#isSet;
+  static get lateExtensionField1 = get self::Extension|lateExtensionField1;
+  static field lateExtensionField2Init = self::Extension|lateExtensionField2Init;
+  static method initLateExtensionField2 = self::Extension|initLateExtensionField2;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2#isSet;
+  static get lateExtensionField2 = get self::Extension|lateExtensionField2;
+  static method staticMethod = self::Extension|staticMethod;
+}
+static field core::int? lateTopLevelField1Init;
+static field core::int? _#lateTopLevelField1 = null;
+static field core::bool _#lateTopLevelField1#isSet = false;
+static field core::int? Extension|lateExtensionField1Init;
+static field core::int? _#Extension|lateExtensionField1 = null;
+static field core::bool _#Extension|lateExtensionField1#isSet = false;
+static field core::int? Extension|lateExtensionField2Init;
+static field core::int? _#Extension|lateExtensionField2 = null;
+static field core::bool _#Extension|lateExtensionField2#isSet = false;
+static method initLateTopLevelField1(core::int value) → core::int? {
+  return self::lateTopLevelField1Init = value;
+}
+static get lateTopLevelField1() → core::int? {
+  if(!self::_#lateTopLevelField1#isSet) {
+    final core::int? #t5 = self::initLateTopLevelField1(123);
+    if(self::_#lateTopLevelField1#isSet)
+      throw new _in::LateError::fieldADI("lateTopLevelField1");
+    self::_#lateTopLevelField1 = #t5;
+    self::_#lateTopLevelField1#isSet = true;
+  }
+  return self::_#lateTopLevelField1;
+}
+static method Extension|initLateExtensionField1(core::int value) → core::int? {
+  return self::Extension|lateExtensionField1Init = value;
+}
+static get Extension|lateExtensionField1() → core::int? {
+  if(!self::_#Extension|lateExtensionField1#isSet) {
+    final core::int? #t6 = self::Extension|initLateExtensionField1(87);
+    if(self::_#Extension|lateExtensionField1#isSet)
+      throw new _in::LateError::fieldADI("lateExtensionField1");
+    self::_#Extension|lateExtensionField1 = #t6;
+    self::_#Extension|lateExtensionField1#isSet = true;
+  }
+  return self::_#Extension|lateExtensionField1;
+}
+static method Extension|initLateExtensionField2(core::int value) → core::int? {
+  return self::Extension|lateExtensionField2Init = value;
+}
+static get Extension|lateExtensionField2() → core::int? {
+  if(!self::_#Extension|lateExtensionField2#isSet) {
+    final core::int? #t7 = self::Extension|initLateExtensionField2(42);
+    if(self::_#Extension|lateExtensionField2#isSet)
+      throw new _in::LateError::fieldADI("lateExtensionField2");
+    self::_#Extension|lateExtensionField2 = #t7;
+    self::_#Extension|lateExtensionField2#isSet = true;
+  }
+  return self::_#Extension|lateExtensionField2;
+}
+static method Extension|staticMethod() → dynamic {
+  self::expect(null, self::Extension|lateExtensionField2Init);
+  self::expect(42, self::Extension|lateExtensionField2);
+  self::expect(42, self::Extension|lateExtensionField2Init);
+}
+static method main() → dynamic {
+  self::expect(null, self::lateTopLevelField1Init);
+  self::expect(123, self::lateTopLevelField1);
+  self::expect(123, self::lateTopLevelField1Init);
+  self::expect(null, self::Class::lateStaticField1Init);
+  self::expect(87, self::Class::lateStaticField1);
+  self::expect(87, self::Class::lateStaticField1Init);
+  self::Class::staticMethod();
+  new self::Class::•<core::int?>(null).{self::Class::instanceMethod}(){() → dynamic};
+  new self::Class::•<core::int?>(0).{self::Class::instanceMethod}(){() → dynamic};
+  new self::Class::•<core::int>(0).{self::Class::instanceMethod}(){() → dynamic};
+  self::expect(null, self::Extension|lateExtensionField1Init);
+  self::expect(87, self::Extension|lateExtensionField1);
+  self::expect(87, self::Extension|lateExtensionField1Init);
+  self::Extension|staticMethod();
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_final_nullable_field_without_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_final_nullable_field_without_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..ce6ed76
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_final_nullable_field_without_initializer.dart.weak.modular.expect
@@ -0,0 +1,154 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  static field core::int? _#lateStaticField1 = null;
+  static field core::bool _#lateStaticField1#isSet = false;
+  static field core::int? _#lateStaticField2 = null;
+  static field core::bool _#lateStaticField2#isSet = false;
+  field core::int? _#Class#lateInstanceField = null;
+  field core::bool _#Class#lateInstanceField#isSet = false;
+  field self::Class::T? _#Class#lateGenericInstanceField = null;
+  field core::bool _#Class#lateGenericInstanceField#isSet = false;
+  synthetic constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  static get lateStaticField1() → core::int?
+    return self::Class::_#lateStaticField1#isSet ?{core::int?} self::Class::_#lateStaticField1 : throw new _in::LateError::fieldNI("lateStaticField1");
+  static set lateStaticField1(core::int? #t1) → void
+    if(self::Class::_#lateStaticField1#isSet)
+      throw new _in::LateError::fieldAI("lateStaticField1");
+    else {
+      self::Class::_#lateStaticField1#isSet = true;
+      self::Class::_#lateStaticField1 = #t1;
+    }
+  static get lateStaticField2() → core::int?
+    return self::Class::_#lateStaticField2#isSet ?{core::int?} self::Class::_#lateStaticField2 : throw new _in::LateError::fieldNI("lateStaticField2");
+  static set lateStaticField2(core::int? #t2) → void
+    if(self::Class::_#lateStaticField2#isSet)
+      throw new _in::LateError::fieldAI("lateStaticField2");
+    else {
+      self::Class::_#lateStaticField2#isSet = true;
+      self::Class::_#lateStaticField2 = #t2;
+    }
+  static method staticMethod() → dynamic {
+    self::throws(() → core::int? => self::Class::lateStaticField2, "Read value from uninitialized Class.lateStaticField2");
+    self::Class::lateStaticField2 = 42;
+    self::expect(42, self::Class::lateStaticField2);
+    self::throws(() → core::int => self::Class::lateStaticField2 = 43, "Write value to initialized Class.lateStaticField2");
+  }
+  get lateInstanceField() → core::int?
+    return this.{self::Class::_#Class#lateInstanceField#isSet}{core::bool} ?{core::int?} this.{self::Class::_#Class#lateInstanceField}{core::int?} : throw new _in::LateError::fieldNI("lateInstanceField");
+  set lateInstanceField(core::int? #t3) → void
+    if(this.{self::Class::_#Class#lateInstanceField#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("lateInstanceField");
+    else {
+      this.{self::Class::_#Class#lateInstanceField#isSet} = true;
+      this.{self::Class::_#Class#lateInstanceField} = #t3;
+    }
+  get lateGenericInstanceField() → self::Class::T?
+    return this.{self::Class::_#Class#lateGenericInstanceField#isSet}{core::bool} ?{self::Class::T?} this.{self::Class::_#Class#lateGenericInstanceField}{self::Class::T?} : throw new _in::LateError::fieldNI("lateGenericInstanceField");
+  set lateGenericInstanceField(self::Class::T? #t4) → void
+    if(this.{self::Class::_#Class#lateGenericInstanceField#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("lateGenericInstanceField");
+    else {
+      this.{self::Class::_#Class#lateGenericInstanceField#isSet} = true;
+      this.{self::Class::_#Class#lateGenericInstanceField} = #t4;
+    }
+  method instanceMethod(covariant-by-class self::Class::T% value) → dynamic {
+    self::throws(() → core::int? => this.{self::Class::lateInstanceField}{core::int?}, "Read value from uninitialized Class.lateInstanceField");
+    this.{self::Class::lateInstanceField} = 16;
+    self::expect(16, this.{self::Class::lateInstanceField}{core::int?});
+    self::throws(() → core::int => this.{self::Class::lateInstanceField} = 17, "Write value to initialized Class.lateInstanceField");
+    self::throws(() → self::Class::T? => this.{self::Class::lateGenericInstanceField}{self::Class::T?}, "Read value from uninitialized Class.lateGenericInstanceField");
+    this.{self::Class::lateGenericInstanceField} = value;
+    self::expect(value, this.{self::Class::lateGenericInstanceField}{self::Class::T?});
+    self::throws(() → self::Class::T% => this.{self::Class::lateGenericInstanceField} = value, "Write value to initialized Class.lateGenericInstanceField");
+  }
+}
+extension Extension<T extends core::Object? = dynamic> on self::Class<T%> {
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1;
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1#isSet;
+  static get lateExtensionField1 = get self::Extension|lateExtensionField1;
+  static set lateExtensionField1 = set self::Extension|lateExtensionField1;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2#isSet;
+  static get lateExtensionField2 = get self::Extension|lateExtensionField2;
+  static set lateExtensionField2 = set self::Extension|lateExtensionField2;
+  static method staticMethod = self::Extension|staticMethod;
+}
+static field core::int? _#lateTopLevelField = null;
+static field core::bool _#lateTopLevelField#isSet = false;
+static field core::int? _#Extension|lateExtensionField1 = null;
+static field core::bool _#Extension|lateExtensionField1#isSet = false;
+static field core::int? _#Extension|lateExtensionField2 = null;
+static field core::bool _#Extension|lateExtensionField2#isSet = false;
+static get lateTopLevelField() → core::int?
+  return self::_#lateTopLevelField#isSet ?{core::int?} self::_#lateTopLevelField : throw new _in::LateError::fieldNI("lateTopLevelField");
+static set lateTopLevelField(core::int? #t5) → void
+  if(self::_#lateTopLevelField#isSet)
+    throw new _in::LateError::fieldAI("lateTopLevelField");
+  else {
+    self::_#lateTopLevelField#isSet = true;
+    self::_#lateTopLevelField = #t5;
+  }
+static get Extension|lateExtensionField1() → core::int?
+  return self::_#Extension|lateExtensionField1#isSet ?{core::int?} self::_#Extension|lateExtensionField1 : throw new _in::LateError::fieldNI("lateExtensionField1");
+static set Extension|lateExtensionField1(core::int? #t6) → void
+  if(self::_#Extension|lateExtensionField1#isSet)
+    throw new _in::LateError::fieldAI("lateExtensionField1");
+  else {
+    self::_#Extension|lateExtensionField1#isSet = true;
+    self::_#Extension|lateExtensionField1 = #t6;
+  }
+static get Extension|lateExtensionField2() → core::int?
+  return self::_#Extension|lateExtensionField2#isSet ?{core::int?} self::_#Extension|lateExtensionField2 : throw new _in::LateError::fieldNI("lateExtensionField2");
+static set Extension|lateExtensionField2(core::int? #t7) → void
+  if(self::_#Extension|lateExtensionField2#isSet)
+    throw new _in::LateError::fieldAI("lateExtensionField2");
+  else {
+    self::_#Extension|lateExtensionField2#isSet = true;
+    self::_#Extension|lateExtensionField2 = #t7;
+  }
+static method Extension|staticMethod() → dynamic {
+  self::throws(() → core::int? => self::Extension|lateExtensionField2, "Read value from uninitialized Class.lateExtensionField2");
+  self::Extension|lateExtensionField2 = 42;
+  self::expect(42, self::Extension|lateExtensionField2);
+  self::throws(() → core::int => self::Extension|lateExtensionField2 = 43, "Write value to initialized Class.lateExtensionField2");
+}
+static method main() → dynamic {
+  self::throws(() → core::int? => self::lateTopLevelField, "Read value from uninitialized lateTopLevelField");
+  self::lateTopLevelField = 123;
+  self::expect(123, self::lateTopLevelField);
+  self::throws(() → core::int => self::lateTopLevelField = 124, "Write value to initialized lateTopLevelField");
+  self::throws(() → core::int? => self::Class::lateStaticField1, "Read value from uninitialized Class.lateStaticField1");
+  self::Class::lateStaticField1 = 87;
+  self::expect(87, self::Class::lateStaticField1);
+  self::throws(() → core::int => self::Class::lateStaticField1 = 88, "Write value to initialized Class.lateStaticField1");
+  self::Class::staticMethod();
+  new self::Class::•<core::int?>().{self::Class::instanceMethod}(null){(core::int?) → dynamic};
+  new self::Class::•<core::int?>().{self::Class::instanceMethod}(0){(core::int?) → dynamic};
+  new self::Class::•<core::int>().{self::Class::instanceMethod}(0){(core::int) → dynamic};
+  self::throws(() → core::int? => self::Extension|lateExtensionField1, "Read value from uninitialized Extension.lateExtensionField1");
+  self::Extension|lateExtensionField1 = 87;
+  self::expect(87, self::Extension|lateExtensionField1);
+  self::throws(() → core::int => self::Extension|lateExtensionField1 = 88, "Write value to initialized Extension.lateExtensionField1");
+  self::Extension|staticMethod();
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_final_nullable_local_with_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_final_nullable_local_with_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..9d9501d
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_final_nullable_local_with_initializer.dart.weak.modular.expect
@@ -0,0 +1,54 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+static method main() → dynamic {
+  core::int? lateLocalInit;
+  function initLateLocal(core::int? value) → core::int? {
+    return lateLocalInit = value;
+  }
+  lowered final core::int? #lateLocal;
+  lowered core::bool #lateLocal#isSet = false;
+  function #lateLocal#get() → core::int? {
+    if(!#lateLocal#isSet) {
+      final core::int? #t1 = initLateLocal(123){(core::int?) → core::int?};
+      if(#lateLocal#isSet)
+        throw new _in::LateError::localADI("lateLocal");
+      #lateLocal = #t1;
+      #lateLocal#isSet = true;
+    }
+    return #lateLocal;
+  }
+  self::expect(null, lateLocalInit);
+  self::expect(123, #lateLocal#get(){() → core::int?});
+  self::expect(123, lateLocalInit);
+  function local<T extends core::Object? = dynamic>(T? value) → Null {
+    T? lateGenericLocalInit;
+    function initLateGenericLocal(T? value) → T? {
+      return lateGenericLocalInit = value;
+    }
+    lowered final T? #lateGenericLocal;
+    lowered core::bool #lateGenericLocal#isSet = false;
+    function #lateGenericLocal#get() → T? {
+      if(!#lateGenericLocal#isSet) {
+        final T? #t2 = initLateGenericLocal(value){(T?) → T?};
+        if(#lateGenericLocal#isSet)
+          throw new _in::LateError::localADI("lateGenericLocal");
+        #lateGenericLocal = #t2;
+        #lateGenericLocal#isSet = true;
+      }
+      return #lateGenericLocal;
+    }
+    self::expect(null, lateGenericLocalInit);
+    self::expect(value, #lateGenericLocal#get(){() → T?});
+    self::expect(value, lateGenericLocalInit);
+  }
+  local<core::int?>(null){(core::int?) → Null};
+  local<core::int?>(42){(core::int?) → Null};
+  local<core::int>(42){(core::int?) → Null};
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_final_nullable_local_without_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_final_nullable_local_without_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..751ada1
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_final_nullable_local_without_initializer.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+static method main() → dynamic {
+  lowered final core::int? #lateLocal;
+  lowered core::bool #lateLocal#isSet = false;
+  function #lateLocal#get() → core::int?
+    return #lateLocal#isSet ?{core::int?} #lateLocal : throw new _in::LateError::localNI("lateLocal");
+  function #lateLocal#set(core::int? #t1) → dynamic
+    if(#lateLocal#isSet)
+      throw new _in::LateError::localAI("lateLocal");
+    else {
+      #lateLocal#isSet = true;
+      return #lateLocal = #t1;
+    }
+  self::throws(() → core::int? => #lateLocal#get(){() → core::int?}, "Read value from uninitialized lateLocal");
+  if(1 =={core::num::==}{(core::Object) → core::bool} 1) {
+    self::expect(123, #lateLocal#set(123){(core::int?) → dynamic});
+  }
+  self::expect(123, #lateLocal#get(){() → core::int?});
+  self::throws(() → core::int => #lateLocal#set(124){(core::int?) → dynamic}, "Write value to initialized lateLocal");
+  function local<T extends core::Object? = dynamic>(T? value) → Null {
+    lowered final T? #lateGenericLocal;
+    lowered core::bool #lateGenericLocal#isSet = false;
+    function #lateGenericLocal#get() → T?
+      return #lateGenericLocal#isSet ?{T?} #lateGenericLocal : throw new _in::LateError::localNI("lateGenericLocal");
+    function #lateGenericLocal#set(T? #t2) → dynamic
+      if(#lateGenericLocal#isSet)
+        throw new _in::LateError::localAI("lateGenericLocal");
+      else {
+        #lateGenericLocal#isSet = true;
+        return #lateGenericLocal = #t2;
+      }
+    self::throws(() → T? => #lateGenericLocal#get(){() → T?}, "Read value from uninitialized lateGenericLocal");
+    if(1 =={core::num::==}{(core::Object) → core::bool} 1) {
+      self::expect(value, #lateGenericLocal#set(value){(T?) → dynamic});
+    }
+    self::expect(value, #lateGenericLocal#get(){() → T?});
+    self::throws(() → T? => #lateGenericLocal#set(value){(T?) → dynamic}, "Write value to initialized lateGenericLocal");
+  }
+  local<core::int?>(null){(core::int?) → Null};
+  local<core::int?>(0){(core::int?) → Null};
+  local<core::int>(null){(core::int?) → Null};
+  local<core::int>(0){(core::int?) → Null};
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_future_or.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_future_or.dart.weak.modular.expect
new file mode 100644
index 0000000..b358ead
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_future_or.dart.weak.modular.expect
@@ -0,0 +1,185 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+import "dart:async";
+
+class C<T extends core::Object? = dynamic> extends core::Object {
+  field FutureOr<dynamic>? _#C#field1 = null;
+  field core::bool _#C#field1#isSet = false;
+  field FutureOr<dynamic>? _#C#field2 = null;
+  field core::bool _#C#field2#isSet = false;
+  covariant-by-class field FutureOr<self::C::T%>? _#C#field3 = null;
+  field core::bool _#C#field3#isSet = false;
+  covariant-by-class field FutureOr<self::C::T?>? _#C#field4 = null;
+  field core::bool _#C#field4#isSet = false;
+  covariant-by-class field FutureOr<self::C::T?>? _#C#field5 = null;
+  field core::bool _#C#field5#isSet = false;
+  synthetic constructor •() → self::C<self::C::T%>
+    : super core::Object::•()
+    ;
+  get field1() → FutureOr<dynamic>
+    return this.{self::C::_#C#field1#isSet}{core::bool} ?{FutureOr<dynamic>} this.{self::C::_#C#field1}{FutureOr<dynamic>?} : throw new _in::LateError::fieldNI("field1");
+  set field1(FutureOr<dynamic>#t1) → void {
+    this.{self::C::_#C#field1#isSet} = true;
+    this.{self::C::_#C#field1} = #t1;
+  }
+  get field2() → FutureOr<dynamic>?
+    return this.{self::C::_#C#field2#isSet}{core::bool} ?{FutureOr<dynamic>?} this.{self::C::_#C#field2}{FutureOr<dynamic>?} : throw new _in::LateError::fieldNI("field2");
+  set field2(FutureOr<dynamic>? #t2) → void {
+    this.{self::C::_#C#field2#isSet} = true;
+    this.{self::C::_#C#field2} = #t2;
+  }
+  get field3() → FutureOr<self::C::T%>
+    return this.{self::C::_#C#field3#isSet}{core::bool} ?{FutureOr<self::C::T%>} let final FutureOr<self::C::T%>? #t3 = this.{self::C::_#C#field3}{FutureOr<self::C::T%>?} in #t3{FutureOr<self::C::T%>} : throw new _in::LateError::fieldNI("field3");
+  set field3(covariant-by-class FutureOr<self::C::T%>#t4) → void {
+    this.{self::C::_#C#field3#isSet} = true;
+    this.{self::C::_#C#field3} = #t4;
+  }
+  get field4() → FutureOr<self::C::T?>
+    return this.{self::C::_#C#field4#isSet}{core::bool} ?{FutureOr<self::C::T?>} this.{self::C::_#C#field4}{FutureOr<self::C::T?>?} : throw new _in::LateError::fieldNI("field4");
+  set field4(covariant-by-class FutureOr<self::C::T?>#t5) → void {
+    this.{self::C::_#C#field4#isSet} = true;
+    this.{self::C::_#C#field4} = #t5;
+  }
+  get field5() → FutureOr<self::C::T?>?
+    return this.{self::C::_#C#field5#isSet}{core::bool} ?{FutureOr<self::C::T?>?} this.{self::C::_#C#field5}{FutureOr<self::C::T?>?} : throw new _in::LateError::fieldNI("field5");
+  set field5(covariant-by-class FutureOr<self::C::T?>? #t6) → void {
+    this.{self::C::_#C#field5#isSet} = true;
+    this.{self::C::_#C#field5} = #t6;
+  }
+  method method() → dynamic {
+    lowered FutureOr<dynamic>? #local1;
+    lowered core::bool #local1#isSet = false;
+    function #local1#get() → FutureOr<dynamic>
+      return #local1#isSet ?{FutureOr<dynamic>} #local1 : throw new _in::LateError::localNI("local1");
+    function #local1#set(FutureOr<dynamic>#t7) → dynamic {
+      #local1#isSet = true;
+      return #local1 = #t7;
+    }
+    lowered FutureOr<dynamic>? #local2;
+    lowered core::bool #local2#isSet = false;
+    function #local2#get() → FutureOr<dynamic>?
+      return #local2#isSet ?{FutureOr<dynamic>?} #local2 : throw new _in::LateError::localNI("local2");
+    function #local2#set(FutureOr<dynamic>? #t8) → dynamic {
+      #local2#isSet = true;
+      return #local2 = #t8;
+    }
+    lowered FutureOr<self::C::T%>? #local3;
+    lowered core::bool #local3#isSet = false;
+    function #local3#get() → FutureOr<self::C::T%>
+      return #local3#isSet ?{FutureOr<self::C::T%>} #local3{FutureOr<self::C::T%>} : throw new _in::LateError::localNI("local3");
+    function #local3#set(FutureOr<self::C::T%>#t9) → dynamic {
+      #local3#isSet = true;
+      return #local3 = #t9;
+    }
+    lowered FutureOr<self::C::T?>? #local4;
+    lowered core::bool #local4#isSet = false;
+    function #local4#get() → FutureOr<self::C::T?>
+      return #local4#isSet ?{FutureOr<self::C::T?>} #local4 : throw new _in::LateError::localNI("local4");
+    function #local4#set(FutureOr<self::C::T?>#t10) → dynamic {
+      #local4#isSet = true;
+      return #local4 = #t10;
+    }
+    lowered FutureOr<self::C::T?>? #local5;
+    lowered core::bool #local5#isSet = false;
+    function #local5#get() → FutureOr<self::C::T?>?
+      return #local5#isSet ?{FutureOr<self::C::T?>?} #local5 : throw new _in::LateError::localNI("local5");
+    function #local5#set(FutureOr<self::C::T?>? #t11) → dynamic {
+      #local5#isSet = true;
+      return #local5 = #t11;
+    }
+  }
+}
+static field FutureOr<dynamic>? _#field1 = null;
+static field core::bool _#field1#isSet = false;
+static field FutureOr<dynamic>? _#field2 = null;
+static field core::bool _#field2#isSet = false;
+static field FutureOr<dynamic>? _#field3 = null;
+static field core::bool _#field3#isSet = false;
+static field FutureOr<core::int>? _#field4 = null;
+static field core::bool _#field4#isSet = false;
+static field FutureOr<core::int?>? _#field5 = null;
+static field core::bool _#field5#isSet = false;
+static field FutureOr<core::int?>? _#field6 = null;
+static field core::bool _#field6#isSet = false;
+static method method1() → FutureOr<dynamic>
+  return null;
+static method method2() → FutureOr<dynamic>?
+  return null;
+static method method3() → FutureOr<dynamic>
+  return null;
+static method method4() → FutureOr<core::int>
+  return 0;
+static method method5() → FutureOr<core::int?>
+  return null;
+static method method6() → FutureOr<core::int?>?
+  return null;
+static get field1() → FutureOr<dynamic> {
+  if(!self::_#field1#isSet) {
+    self::_#field1 = self::method1();
+    self::_#field1#isSet = true;
+  }
+  return self::_#field1;
+}
+static set field1(FutureOr<dynamic>#t12) → void {
+  self::_#field1#isSet = true;
+  self::_#field1 = #t12;
+}
+static get field2() → FutureOr<dynamic>? {
+  if(!self::_#field2#isSet) {
+    self::_#field2 = self::method2();
+    self::_#field2#isSet = true;
+  }
+  return self::_#field2;
+}
+static set field2(FutureOr<dynamic>? #t13) → void {
+  self::_#field2#isSet = true;
+  self::_#field2 = #t13;
+}
+static get field3() → FutureOr<dynamic> {
+  if(!self::_#field3#isSet) {
+    self::_#field3 = self::method3();
+    self::_#field3#isSet = true;
+  }
+  return self::_#field3;
+}
+static set field3(FutureOr<dynamic>#t14) → void {
+  self::_#field3#isSet = true;
+  self::_#field3 = #t14;
+}
+static get field4() → FutureOr<core::int> {
+  if(!self::_#field4#isSet) {
+    self::_#field4 = self::method4();
+    self::_#field4#isSet = true;
+  }
+  return let final FutureOr<core::int>? #t15 = self::_#field4 in #t15{FutureOr<core::int>};
+}
+static set field4(FutureOr<core::int>#t16) → void {
+  self::_#field4#isSet = true;
+  self::_#field4 = #t16;
+}
+static get field5() → FutureOr<core::int?> {
+  if(!self::_#field5#isSet) {
+    self::_#field5 = self::method5();
+    self::_#field5#isSet = true;
+  }
+  return self::_#field5;
+}
+static set field5(FutureOr<core::int?>#t17) → void {
+  self::_#field5#isSet = true;
+  self::_#field5 = #t17;
+}
+static get field6() → FutureOr<core::int?>? {
+  if(!self::_#field6#isSet) {
+    self::_#field6 = self::method6();
+    self::_#field6#isSet = true;
+  }
+  return self::_#field6;
+}
+static set field6(FutureOr<core::int?>? #t18) → void {
+  self::_#field6#isSet = true;
+  self::_#field6 = #t18;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/late_lowering/late_local_with_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_local_with_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..caa8e52
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_local_with_initializer.dart.weak.modular.expect
@@ -0,0 +1,47 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  lowered core::int? #lateLocal;
+  lowered core::bool #lateLocal#isSet = false;
+  function #lateLocal#get() → core::int {
+    if(!#lateLocal#isSet) {
+      #lateLocal = 123;
+      #lateLocal#isSet = true;
+    }
+    return #lateLocal{core::int};
+  }
+  function #lateLocal#set(core::int #t1) → dynamic {
+    #lateLocal#isSet = true;
+    return #lateLocal = #t1;
+  }
+  self::expect(123, #lateLocal#get(){() → core::int});
+  self::expect(124, #lateLocal#set(124){(core::int) → dynamic});
+  self::expect(124, #lateLocal#get(){() → core::int});
+  function local<T extends core::Object? = dynamic>(T% value1, T% value2) → Null {
+    lowered T? #lateGenericLocal;
+    lowered core::bool #lateGenericLocal#isSet = false;
+    function #lateGenericLocal#get() → T% {
+      if(!#lateGenericLocal#isSet) {
+        #lateGenericLocal = value1;
+        #lateGenericLocal#isSet = true;
+      }
+      return #lateGenericLocal{T%};
+    }
+    function #lateGenericLocal#set(T% #t2) → dynamic {
+      #lateGenericLocal#isSet = true;
+      return #lateGenericLocal = #t2;
+    }
+    self::expect(value1, #lateGenericLocal#get(){() → T%});
+    self::expect(value2, #lateGenericLocal#set(value2){(T%) → dynamic});
+    self::expect(value2, #lateGenericLocal#get(){() → T%});
+  }
+  local<core::int?>(null, 0){(core::int?, core::int?) → Null};
+  local<core::int?>(0, null){(core::int?, core::int?) → Null};
+  local<core::int>(0, 42){(core::int, core::int) → Null};
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_local_without_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_local_without_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..c6c3b91
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_local_without_initializer.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+static method main() → dynamic {
+  lowered core::int? #lateLocal;
+  lowered core::bool #lateLocal#isSet = false;
+  function #lateLocal#get() → core::int
+    return #lateLocal#isSet ?{core::int} #lateLocal{core::int} : throw new _in::LateError::localNI("lateLocal");
+  function #lateLocal#set(core::int #t1) → dynamic {
+    #lateLocal#isSet = true;
+    return #lateLocal = #t1;
+  }
+  self::throws(() → core::int => #lateLocal#get(){() → core::int}, "Read value from uninitialized lateLocal");
+  self::expect(123, #lateLocal#set(123){(core::int) → dynamic});
+  self::expect(123, #lateLocal#get(){() → core::int});
+  function local<T extends core::Object? = dynamic>(T% value) → Null {
+    lowered T? #lateGenericLocal;
+    lowered core::bool #lateGenericLocal#isSet = false;
+    function #lateGenericLocal#get() → T%
+      return #lateGenericLocal#isSet ?{T%} #lateGenericLocal{T%} : throw new _in::LateError::localNI("lateGenericLocal");
+    function #lateGenericLocal#set(T% #t2) → dynamic {
+      #lateGenericLocal#isSet = true;
+      return #lateGenericLocal = #t2;
+    }
+    self::throws(() → T% => #lateGenericLocal#get(){() → T%}, "Read value from uninitialized lateGenericLocal");
+    self::expect(value, #lateGenericLocal#set(value){(T%) → dynamic});
+    self::expect(value, #lateGenericLocal#get(){() → T%});
+  }
+  local<core::int?>(null){(core::int?) → Null};
+  local<core::int?>(0){(core::int?) → Null};
+  local<core::int>(0){(core::int) → Null};
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_lowering_bitmasks.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_lowering_bitmasks.dart.weak.modular.expect
new file mode 100644
index 0000000..4c7909a
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_lowering_bitmasks.dart.weak.modular.expect
@@ -0,0 +1,233 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class extends core::Object {
+  static field core::int? _#uninitializedNonFinalStaticField = null;
+  static field core::bool _#uninitializedNonFinalStaticField#isSet = false;
+  static field core::int? _#uninitializedFinalStaticField = null;
+  static field core::bool _#uninitializedFinalStaticField#isSet = false;
+  static field core::int? _#initializedNonFinalStaticField = null;
+  static field core::bool _#initializedNonFinalStaticField#isSet = false;
+  static field core::int? _#initializedFinalStaticField = null;
+  static field core::bool _#initializedFinalStaticField#isSet = false;
+  field core::int? _#Class#uninitializedNonFinalInstanceField = null;
+  field core::bool _#Class#uninitializedNonFinalInstanceField#isSet = false;
+  field core::int? _#Class#uninitializedFinalInstanceField = null;
+  field core::bool _#Class#uninitializedFinalInstanceField#isSet = false;
+  field core::int? _#Class#initializedNonFinalInstanceField = null;
+  field core::bool _#Class#initializedNonFinalInstanceField#isSet = false;
+  field core::int? _#Class#initializedFinalInstanceField = null;
+  field core::bool _#Class#initializedFinalInstanceField#isSet = false;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  static get uninitializedNonFinalStaticField() → core::int
+    return self::Class::_#uninitializedNonFinalStaticField#isSet ?{core::int} let final core::int? #t1 = self::Class::_#uninitializedNonFinalStaticField in #t1{core::int} : throw new _in::LateError::fieldNI("uninitializedNonFinalStaticField");
+  static set uninitializedNonFinalStaticField(core::int #t2) → void {
+    self::Class::_#uninitializedNonFinalStaticField#isSet = true;
+    self::Class::_#uninitializedNonFinalStaticField = #t2;
+  }
+  static get uninitializedFinalStaticField() → core::int
+    return self::Class::_#uninitializedFinalStaticField#isSet ?{core::int} let final core::int? #t3 = self::Class::_#uninitializedFinalStaticField in #t3{core::int} : throw new _in::LateError::fieldNI("uninitializedFinalStaticField");
+  static set uninitializedFinalStaticField(core::int #t4) → void
+    if(self::Class::_#uninitializedFinalStaticField#isSet)
+      throw new _in::LateError::fieldAI("uninitializedFinalStaticField");
+    else {
+      self::Class::_#uninitializedFinalStaticField#isSet = true;
+      self::Class::_#uninitializedFinalStaticField = #t4;
+    }
+  static get initializedNonFinalStaticField() → core::int {
+    if(!self::Class::_#initializedNonFinalStaticField#isSet) {
+      self::Class::_#initializedNonFinalStaticField = 0;
+      self::Class::_#initializedNonFinalStaticField#isSet = true;
+    }
+    return let final core::int? #t5 = self::Class::_#initializedNonFinalStaticField in #t5{core::int};
+  }
+  static set initializedNonFinalStaticField(core::int #t6) → void {
+    self::Class::_#initializedNonFinalStaticField#isSet = true;
+    self::Class::_#initializedNonFinalStaticField = #t6;
+  }
+  static get initializedFinalStaticField() → core::int {
+    if(!self::Class::_#initializedFinalStaticField#isSet) {
+      final core::int #t7 = 0;
+      if(self::Class::_#initializedFinalStaticField#isSet)
+        throw new _in::LateError::fieldADI("initializedFinalStaticField");
+      self::Class::_#initializedFinalStaticField = #t7;
+      self::Class::_#initializedFinalStaticField#isSet = true;
+    }
+    return let final core::int? #t8 = self::Class::_#initializedFinalStaticField in #t8{core::int};
+  }
+  get uninitializedNonFinalInstanceField() → core::int
+    return this.{self::Class::_#Class#uninitializedNonFinalInstanceField#isSet}{core::bool} ?{core::int} let final core::int? #t9 = this.{self::Class::_#Class#uninitializedNonFinalInstanceField}{core::int?} in #t9{core::int} : throw new _in::LateError::fieldNI("uninitializedNonFinalInstanceField");
+  set uninitializedNonFinalInstanceField(core::int #t10) → void {
+    this.{self::Class::_#Class#uninitializedNonFinalInstanceField#isSet} = true;
+    this.{self::Class::_#Class#uninitializedNonFinalInstanceField} = #t10;
+  }
+  get uninitializedFinalInstanceField() → core::int
+    return this.{self::Class::_#Class#uninitializedFinalInstanceField#isSet}{core::bool} ?{core::int} let final core::int? #t11 = this.{self::Class::_#Class#uninitializedFinalInstanceField}{core::int?} in #t11{core::int} : throw new _in::LateError::fieldNI("uninitializedFinalInstanceField");
+  set uninitializedFinalInstanceField(core::int #t12) → void
+    if(this.{self::Class::_#Class#uninitializedFinalInstanceField#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("uninitializedFinalInstanceField");
+    else {
+      this.{self::Class::_#Class#uninitializedFinalInstanceField#isSet} = true;
+      this.{self::Class::_#Class#uninitializedFinalInstanceField} = #t12;
+    }
+  get initializedNonFinalInstanceField() → core::int {
+    if(!this.{self::Class::_#Class#initializedNonFinalInstanceField#isSet}{core::bool}) {
+      this.{self::Class::_#Class#initializedNonFinalInstanceField} = 0;
+      this.{self::Class::_#Class#initializedNonFinalInstanceField#isSet} = true;
+    }
+    return let final core::int? #t13 = this.{self::Class::_#Class#initializedNonFinalInstanceField}{core::int?} in #t13{core::int};
+  }
+  set initializedNonFinalInstanceField(core::int #t14) → void {
+    this.{self::Class::_#Class#initializedNonFinalInstanceField#isSet} = true;
+    this.{self::Class::_#Class#initializedNonFinalInstanceField} = #t14;
+  }
+  get initializedFinalInstanceField() → core::int {
+    if(!this.{self::Class::_#Class#initializedFinalInstanceField#isSet}{core::bool}) {
+      final core::int #t15 = 0;
+      if(this.{self::Class::_#Class#initializedFinalInstanceField#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("initializedFinalInstanceField");
+      this.{self::Class::_#Class#initializedFinalInstanceField} = #t15;
+      this.{self::Class::_#Class#initializedFinalInstanceField#isSet} = true;
+    }
+    return let final core::int? #t16 = this.{self::Class::_#Class#initializedFinalInstanceField}{core::int?} in #t16{core::int};
+  }
+}
+static field core::int? _#uninitializedNonFinalTopLevelField = null;
+static field core::bool _#uninitializedNonFinalTopLevelField#isSet = false;
+static field core::int? _#uninitializedFinalTopLevelField = null;
+static field core::bool _#uninitializedFinalTopLevelField#isSet = false;
+static field core::int? _#initializedNonFinalTopLevelField = null;
+static field core::bool _#initializedNonFinalTopLevelField#isSet = false;
+static field core::int? _#initializedFinalTopLevelField = null;
+static field core::bool _#initializedFinalTopLevelField#isSet = false;
+static method main() → dynamic {}
+static method method() → dynamic {
+  lowered core::int? #nullableUninitializedNonFinalLocal;
+  lowered core::bool #nullableUninitializedNonFinalLocal#isSet = false;
+  function #nullableUninitializedNonFinalLocal#get() → core::int?
+    return #nullableUninitializedNonFinalLocal#isSet ?{core::int?} #nullableUninitializedNonFinalLocal : throw new _in::LateError::localNI("nullableUninitializedNonFinalLocal");
+  function #nullableUninitializedNonFinalLocal#set(core::int? #t17) → dynamic {
+    #nullableUninitializedNonFinalLocal#isSet = true;
+    return #nullableUninitializedNonFinalLocal = #t17;
+  }
+  lowered core::int? #nonNullableUninitializedNonFinalLocal;
+  lowered core::bool #nonNullableUninitializedNonFinalLocal#isSet = false;
+  function #nonNullableUninitializedNonFinalLocal#get() → core::int
+    return #nonNullableUninitializedNonFinalLocal#isSet ?{core::int} #nonNullableUninitializedNonFinalLocal{core::int} : throw new _in::LateError::localNI("nonNullableUninitializedNonFinalLocal");
+  function #nonNullableUninitializedNonFinalLocal#set(core::int #t18) → dynamic {
+    #nonNullableUninitializedNonFinalLocal#isSet = true;
+    return #nonNullableUninitializedNonFinalLocal = #t18;
+  }
+  lowered final core::int? #nullableUninitializedFinalLocal;
+  lowered core::bool #nullableUninitializedFinalLocal#isSet = false;
+  function #nullableUninitializedFinalLocal#get() → core::int?
+    return #nullableUninitializedFinalLocal#isSet ?{core::int?} #nullableUninitializedFinalLocal : throw new _in::LateError::localNI("nullableUninitializedFinalLocal");
+  function #nullableUninitializedFinalLocal#set(core::int? #t19) → dynamic
+    if(#nullableUninitializedFinalLocal#isSet)
+      throw new _in::LateError::localAI("nullableUninitializedFinalLocal");
+    else {
+      #nullableUninitializedFinalLocal#isSet = true;
+      return #nullableUninitializedFinalLocal = #t19;
+    }
+  lowered final core::int? #nonNullableUninitializedFinalLocal;
+  lowered core::bool #nonNullableUninitializedFinalLocal#isSet = false;
+  function #nonNullableUninitializedFinalLocal#get() → core::int
+    return #nonNullableUninitializedFinalLocal#isSet ?{core::int} #nonNullableUninitializedFinalLocal{core::int} : throw new _in::LateError::localNI("nonNullableUninitializedFinalLocal");
+  function #nonNullableUninitializedFinalLocal#set(core::int #t20) → dynamic
+    if(#nonNullableUninitializedFinalLocal#isSet)
+      throw new _in::LateError::localAI("nonNullableUninitializedFinalLocal");
+    else {
+      #nonNullableUninitializedFinalLocal#isSet = true;
+      return #nonNullableUninitializedFinalLocal = #t20;
+    }
+  lowered core::int? #nullableInitializedNonFinalLocal;
+  lowered core::bool #nullableInitializedNonFinalLocal#isSet = false;
+  function #nullableInitializedNonFinalLocal#get() → core::int? {
+    if(!#nullableInitializedNonFinalLocal#isSet) {
+      #nullableInitializedNonFinalLocal = 0;
+      #nullableInitializedNonFinalLocal#isSet = true;
+    }
+    return #nullableInitializedNonFinalLocal;
+  }
+  function #nullableInitializedNonFinalLocal#set(core::int? #t21) → dynamic {
+    #nullableInitializedNonFinalLocal#isSet = true;
+    return #nullableInitializedNonFinalLocal = #t21;
+  }
+  lowered core::int? #nonNullableInitializedNonFinalLocal;
+  lowered core::bool #nonNullableInitializedNonFinalLocal#isSet = false;
+  function #nonNullableInitializedNonFinalLocal#get() → core::int {
+    if(!#nonNullableInitializedNonFinalLocal#isSet) {
+      #nonNullableInitializedNonFinalLocal = 0;
+      #nonNullableInitializedNonFinalLocal#isSet = true;
+    }
+    return #nonNullableInitializedNonFinalLocal{core::int};
+  }
+  function #nonNullableInitializedNonFinalLocal#set(core::int #t22) → dynamic {
+    #nonNullableInitializedNonFinalLocal#isSet = true;
+    return #nonNullableInitializedNonFinalLocal = #t22;
+  }
+  lowered final core::int? #nullableInitializedFinalLocal;
+  lowered core::bool #nullableInitializedFinalLocal#isSet = false;
+  function #nullableInitializedFinalLocal#get() → core::int? {
+    if(!#nullableInitializedFinalLocal#isSet) {
+      final core::int? #t23 = 0;
+      if(#nullableInitializedFinalLocal#isSet)
+        throw new _in::LateError::localADI("nullableInitializedFinalLocal");
+      #nullableInitializedFinalLocal = #t23;
+      #nullableInitializedFinalLocal#isSet = true;
+    }
+    return #nullableInitializedFinalLocal;
+  }
+  lowered final core::int? #nonNullableInitializedFinalLocal;
+  lowered core::bool #nonNullableInitializedFinalLocal#isSet = false;
+  function #nonNullableInitializedFinalLocal#get() → core::int {
+    if(!#nonNullableInitializedFinalLocal#isSet) {
+      final core::int #t24 = 0;
+      if(#nonNullableInitializedFinalLocal#isSet)
+        throw new _in::LateError::localADI("nonNullableInitializedFinalLocal");
+      #nonNullableInitializedFinalLocal = #t24;
+      #nonNullableInitializedFinalLocal#isSet = true;
+    }
+    return #nonNullableInitializedFinalLocal{core::int};
+  }
+}
+static get uninitializedNonFinalTopLevelField() → core::int
+  return self::_#uninitializedNonFinalTopLevelField#isSet ?{core::int} let final core::int? #t25 = self::_#uninitializedNonFinalTopLevelField in #t25{core::int} : throw new _in::LateError::fieldNI("uninitializedNonFinalTopLevelField");
+static set uninitializedNonFinalTopLevelField(core::int #t26) → void {
+  self::_#uninitializedNonFinalTopLevelField#isSet = true;
+  self::_#uninitializedNonFinalTopLevelField = #t26;
+}
+static get uninitializedFinalTopLevelField() → core::int
+  return self::_#uninitializedFinalTopLevelField#isSet ?{core::int} let final core::int? #t27 = self::_#uninitializedFinalTopLevelField in #t27{core::int} : throw new _in::LateError::fieldNI("uninitializedFinalTopLevelField");
+static set uninitializedFinalTopLevelField(core::int #t28) → void
+  if(self::_#uninitializedFinalTopLevelField#isSet)
+    throw new _in::LateError::fieldAI("uninitializedFinalTopLevelField");
+  else {
+    self::_#uninitializedFinalTopLevelField#isSet = true;
+    self::_#uninitializedFinalTopLevelField = #t28;
+  }
+static get initializedNonFinalTopLevelField() → core::int {
+  if(!self::_#initializedNonFinalTopLevelField#isSet) {
+    self::_#initializedNonFinalTopLevelField = 0;
+    self::_#initializedNonFinalTopLevelField#isSet = true;
+  }
+  return let final core::int? #t29 = self::_#initializedNonFinalTopLevelField in #t29{core::int};
+}
+static set initializedNonFinalTopLevelField(core::int #t30) → void {
+  self::_#initializedNonFinalTopLevelField#isSet = true;
+  self::_#initializedNonFinalTopLevelField = #t30;
+}
+static get initializedFinalTopLevelField() → core::int {
+  if(!self::_#initializedFinalTopLevelField#isSet) {
+    final core::int #t31 = 0;
+    if(self::_#initializedFinalTopLevelField#isSet)
+      throw new _in::LateError::fieldADI("initializedFinalTopLevelField");
+    self::_#initializedFinalTopLevelField = #t31;
+    self::_#initializedFinalTopLevelField#isSet = true;
+  }
+  return let final core::int? #t32 = self::_#initializedFinalTopLevelField in #t32{core::int};
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_nullable_field_with_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_nullable_field_with_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..a743497
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_nullable_field_with_initializer.dart.weak.modular.expect
@@ -0,0 +1,167 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  static field core::int? _#lateStaticField1 = null;
+  static field core::bool _#lateStaticField1#isSet = false;
+  static field core::int? _#lateStaticField2 = null;
+  static field core::bool _#lateStaticField2#isSet = false;
+  field core::int? _#Class#lateInstanceField = null;
+  field core::bool _#Class#lateInstanceField#isSet = false;
+  final field self::Class::T? field;
+  covariant-by-class field self::Class::T? _#Class#lateGenericInstanceField = null;
+  field core::bool _#Class#lateGenericInstanceField#isSet = false;
+  constructor •(self::Class::T? field) → self::Class<self::Class::T%>
+    : self::Class::field = field, super core::Object::•()
+    ;
+  static method lateStaticField1Init() → core::int?
+    return 87;
+  static get lateStaticField1() → core::int? {
+    if(!self::Class::_#lateStaticField1#isSet) {
+      self::Class::_#lateStaticField1 = self::Class::lateStaticField1Init();
+      self::Class::_#lateStaticField1#isSet = true;
+    }
+    return self::Class::_#lateStaticField1;
+  }
+  static set lateStaticField1(core::int? #t1) → void {
+    self::Class::_#lateStaticField1#isSet = true;
+    self::Class::_#lateStaticField1 = #t1;
+  }
+  static method lateStaticField2Init() → core::int?
+    return 42;
+  static get lateStaticField2() → core::int? {
+    if(!self::Class::_#lateStaticField2#isSet) {
+      self::Class::_#lateStaticField2 = self::Class::lateStaticField2Init();
+      self::Class::_#lateStaticField2#isSet = true;
+    }
+    return self::Class::_#lateStaticField2;
+  }
+  static set lateStaticField2(core::int? #t2) → void {
+    self::Class::_#lateStaticField2#isSet = true;
+    self::Class::_#lateStaticField2 = #t2;
+  }
+  static method staticMethod() → dynamic {
+    self::expect(42, self::Class::lateStaticField2);
+    self::Class::lateStaticField2 = 43;
+    self::expect(43, self::Class::lateStaticField2);
+  }
+  method lateInstanceFieldInit() → core::int?
+    return 16;
+  get lateInstanceField() → core::int? {
+    if(!this.{self::Class::_#Class#lateInstanceField#isSet}{core::bool}) {
+      this.{self::Class::_#Class#lateInstanceField} = this.{self::Class::lateInstanceFieldInit}(){() → core::int?};
+      this.{self::Class::_#Class#lateInstanceField#isSet} = true;
+    }
+    return this.{self::Class::_#Class#lateInstanceField}{core::int?};
+  }
+  set lateInstanceField(core::int? #t3) → void {
+    this.{self::Class::_#Class#lateInstanceField#isSet} = true;
+    this.{self::Class::_#Class#lateInstanceField} = #t3;
+  }
+  method lateGenericInstanceFieldInit() → self::Class::T?
+    return this.{self::Class::field}{self::Class::T?};
+  get lateGenericInstanceField() → self::Class::T? {
+    if(!this.{self::Class::_#Class#lateGenericInstanceField#isSet}{core::bool}) {
+      this.{self::Class::_#Class#lateGenericInstanceField} = this.{self::Class::lateGenericInstanceFieldInit}(){() → self::Class::T?};
+      this.{self::Class::_#Class#lateGenericInstanceField#isSet} = true;
+    }
+    return this.{self::Class::_#Class#lateGenericInstanceField}{self::Class::T?};
+  }
+  set lateGenericInstanceField(covariant-by-class self::Class::T? #t4) → void {
+    this.{self::Class::_#Class#lateGenericInstanceField#isSet} = true;
+    this.{self::Class::_#Class#lateGenericInstanceField} = #t4;
+  }
+  method instanceMethod(covariant-by-class self::Class::T? value) → dynamic {
+    self::expect(16, this.{self::Class::lateInstanceField}{core::int?});
+    this.{self::Class::lateInstanceField} = 17;
+    self::expect(17, this.{self::Class::lateInstanceField}{core::int?});
+    self::expect(this.{self::Class::field}{self::Class::T?}, this.{self::Class::lateGenericInstanceField}{self::Class::T?});
+    this.{self::Class::lateGenericInstanceField} = value;
+    self::expect(value, this.{self::Class::lateGenericInstanceField}{self::Class::T?});
+  }
+}
+extension Extension<T extends core::Object? = dynamic> on self::Class<T%> {
+  static method lateExtensionField1Init = self::Extension|lateExtensionField1Init;
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1;
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1#isSet;
+  static get lateExtensionField1 = get self::Extension|lateExtensionField1;
+  static set lateExtensionField1 = set self::Extension|lateExtensionField1;
+  static method lateExtensionField2Init = self::Extension|lateExtensionField2Init;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2#isSet;
+  static get lateExtensionField2 = get self::Extension|lateExtensionField2;
+  static set lateExtensionField2 = set self::Extension|lateExtensionField2;
+  static method staticMethod = self::Extension|staticMethod;
+}
+static field core::int? _#lateTopLevelField1 = null;
+static field core::bool _#lateTopLevelField1#isSet = false;
+static field core::int? _#Extension|lateExtensionField1 = null;
+static field core::bool _#Extension|lateExtensionField1#isSet = false;
+static field core::int? _#Extension|lateExtensionField2 = null;
+static field core::bool _#Extension|lateExtensionField2#isSet = false;
+static method lateTopLevelField1Init() → core::int?
+  return 123;
+static get lateTopLevelField1() → core::int? {
+  if(!self::_#lateTopLevelField1#isSet) {
+    self::_#lateTopLevelField1 = self::lateTopLevelField1Init();
+    self::_#lateTopLevelField1#isSet = true;
+  }
+  return self::_#lateTopLevelField1;
+}
+static set lateTopLevelField1(core::int? #t5) → void {
+  self::_#lateTopLevelField1#isSet = true;
+  self::_#lateTopLevelField1 = #t5;
+}
+static method Extension|lateExtensionField1Init() → core::int?
+  return 87;
+static get Extension|lateExtensionField1() → core::int? {
+  if(!self::_#Extension|lateExtensionField1#isSet) {
+    self::_#Extension|lateExtensionField1 = self::Extension|lateExtensionField1Init();
+    self::_#Extension|lateExtensionField1#isSet = true;
+  }
+  return self::_#Extension|lateExtensionField1;
+}
+static set Extension|lateExtensionField1(core::int? #t6) → void {
+  self::_#Extension|lateExtensionField1#isSet = true;
+  self::_#Extension|lateExtensionField1 = #t6;
+}
+static method Extension|lateExtensionField2Init() → core::int?
+  return 42;
+static get Extension|lateExtensionField2() → core::int? {
+  if(!self::_#Extension|lateExtensionField2#isSet) {
+    self::_#Extension|lateExtensionField2 = self::Extension|lateExtensionField2Init();
+    self::_#Extension|lateExtensionField2#isSet = true;
+  }
+  return self::_#Extension|lateExtensionField2;
+}
+static set Extension|lateExtensionField2(core::int? #t7) → void {
+  self::_#Extension|lateExtensionField2#isSet = true;
+  self::_#Extension|lateExtensionField2 = #t7;
+}
+static method Extension|staticMethod() → dynamic {
+  self::expect(42, self::Extension|lateExtensionField2);
+  self::Extension|lateExtensionField2 = 43;
+  self::expect(43, self::Extension|lateExtensionField2);
+}
+static method main() → dynamic {
+  self::expect(123, self::lateTopLevelField1);
+  self::lateTopLevelField1 = 124;
+  self::expect(124, self::lateTopLevelField1);
+  self::expect(87, self::Class::lateStaticField1);
+  self::Class::lateStaticField1 = 88;
+  self::expect(88, self::Class::lateStaticField1);
+  self::Class::staticMethod();
+  new self::Class::•<core::int?>(null).{self::Class::instanceMethod}(0){(core::int?) → dynamic};
+  new self::Class::•<core::int?>(0).{self::Class::instanceMethod}(null){(core::int?) → dynamic};
+  new self::Class::•<core::int>(null).{self::Class::instanceMethod}(0){(core::int?) → dynamic};
+  new self::Class::•<core::int>(0).{self::Class::instanceMethod}(null){(core::int?) → dynamic};
+  self::expect(87, self::Extension|lateExtensionField1);
+  self::Extension|lateExtensionField1 = 88;
+  self::expect(88, self::Extension|lateExtensionField1);
+  self::Extension|staticMethod();
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_nullable_field_without_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_nullable_field_without_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..91ed9ea
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_nullable_field_without_initializer.dart.weak.modular.expect
@@ -0,0 +1,127 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  static field core::int? _#lateStaticField1 = null;
+  static field core::bool _#lateStaticField1#isSet = false;
+  static field core::int? _#lateStaticField2 = null;
+  static field core::bool _#lateStaticField2#isSet = false;
+  field core::int? _#Class#lateInstanceField = null;
+  field core::bool _#Class#lateInstanceField#isSet = false;
+  covariant-by-class field self::Class::T? _#Class#lateGenericInstanceField = null;
+  field core::bool _#Class#lateGenericInstanceField#isSet = false;
+  synthetic constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  static get lateStaticField1() → core::int?
+    return self::Class::_#lateStaticField1#isSet ?{core::int?} self::Class::_#lateStaticField1 : throw new _in::LateError::fieldNI("lateStaticField1");
+  static set lateStaticField1(core::int? #t1) → void {
+    self::Class::_#lateStaticField1#isSet = true;
+    self::Class::_#lateStaticField1 = #t1;
+  }
+  static get lateStaticField2() → core::int?
+    return self::Class::_#lateStaticField2#isSet ?{core::int?} self::Class::_#lateStaticField2 : throw new _in::LateError::fieldNI("lateStaticField2");
+  static set lateStaticField2(core::int? #t2) → void {
+    self::Class::_#lateStaticField2#isSet = true;
+    self::Class::_#lateStaticField2 = #t2;
+  }
+  static method staticMethod() → dynamic {
+    self::throws(() → core::int? => self::Class::lateStaticField2, "Read value from uninitialized Class.lateStaticField2");
+    self::Class::lateStaticField2 = 42;
+    self::expect(42, self::Class::lateStaticField2);
+  }
+  get lateInstanceField() → core::int?
+    return this.{self::Class::_#Class#lateInstanceField#isSet}{core::bool} ?{core::int?} this.{self::Class::_#Class#lateInstanceField}{core::int?} : throw new _in::LateError::fieldNI("lateInstanceField");
+  set lateInstanceField(core::int? #t3) → void {
+    this.{self::Class::_#Class#lateInstanceField#isSet} = true;
+    this.{self::Class::_#Class#lateInstanceField} = #t3;
+  }
+  get lateGenericInstanceField() → self::Class::T?
+    return this.{self::Class::_#Class#lateGenericInstanceField#isSet}{core::bool} ?{self::Class::T?} this.{self::Class::_#Class#lateGenericInstanceField}{self::Class::T?} : throw new _in::LateError::fieldNI("lateGenericInstanceField");
+  set lateGenericInstanceField(covariant-by-class self::Class::T? #t4) → void {
+    this.{self::Class::_#Class#lateGenericInstanceField#isSet} = true;
+    this.{self::Class::_#Class#lateGenericInstanceField} = #t4;
+  }
+  method instanceMethod(covariant-by-class self::Class::T? value) → dynamic {
+    self::throws(() → core::int? => this.{self::Class::lateInstanceField}{core::int?}, "Read value from uninitialized Class.lateInstanceField");
+    this.{self::Class::lateInstanceField} = 16;
+    self::expect(16, this.{self::Class::lateInstanceField}{core::int?});
+    self::throws(() → self::Class::T? => this.{self::Class::lateGenericInstanceField}{self::Class::T?}, "Read value from uninitialized Class.lateGenericInstanceField");
+    this.{self::Class::lateGenericInstanceField} = value;
+    self::expect(value, this.{self::Class::lateGenericInstanceField}{self::Class::T?});
+  }
+}
+extension Extension<T extends core::Object? = dynamic> on self::Class<T%> {
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1;
+  static field lateExtensionField1 = self::_#Extension|lateExtensionField1#isSet;
+  static get lateExtensionField1 = get self::Extension|lateExtensionField1;
+  static set lateExtensionField1 = set self::Extension|lateExtensionField1;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2;
+  static field lateExtensionField2 = self::_#Extension|lateExtensionField2#isSet;
+  static get lateExtensionField2 = get self::Extension|lateExtensionField2;
+  static set lateExtensionField2 = set self::Extension|lateExtensionField2;
+  static method staticMethod = self::Extension|staticMethod;
+}
+static field core::int? _#lateTopLevelField = null;
+static field core::bool _#lateTopLevelField#isSet = false;
+static field core::int? _#Extension|lateExtensionField1 = null;
+static field core::bool _#Extension|lateExtensionField1#isSet = false;
+static field core::int? _#Extension|lateExtensionField2 = null;
+static field core::bool _#Extension|lateExtensionField2#isSet = false;
+static get lateTopLevelField() → core::int?
+  return self::_#lateTopLevelField#isSet ?{core::int?} self::_#lateTopLevelField : throw new _in::LateError::fieldNI("lateTopLevelField");
+static set lateTopLevelField(core::int? #t5) → void {
+  self::_#lateTopLevelField#isSet = true;
+  self::_#lateTopLevelField = #t5;
+}
+static get Extension|lateExtensionField1() → core::int?
+  return self::_#Extension|lateExtensionField1#isSet ?{core::int?} self::_#Extension|lateExtensionField1 : throw new _in::LateError::fieldNI("lateExtensionField1");
+static set Extension|lateExtensionField1(core::int? #t6) → void {
+  self::_#Extension|lateExtensionField1#isSet = true;
+  self::_#Extension|lateExtensionField1 = #t6;
+}
+static get Extension|lateExtensionField2() → core::int?
+  return self::_#Extension|lateExtensionField2#isSet ?{core::int?} self::_#Extension|lateExtensionField2 : throw new _in::LateError::fieldNI("lateExtensionField2");
+static set Extension|lateExtensionField2(core::int? #t7) → void {
+  self::_#Extension|lateExtensionField2#isSet = true;
+  self::_#Extension|lateExtensionField2 = #t7;
+}
+static method Extension|staticMethod() → dynamic {
+  self::throws(() → core::int? => self::Extension|lateExtensionField2, "Read value from uninitialized Class.lateExtensionField2");
+  self::Extension|lateExtensionField2 = 42;
+  self::expect(42, self::Extension|lateExtensionField2);
+}
+static method main() → dynamic {
+  self::throws(() → core::int? => self::lateTopLevelField, "Read value from uninitialized lateTopLevelField");
+  self::lateTopLevelField = 123;
+  self::expect(123, self::lateTopLevelField);
+  self::throws(() → core::int? => self::Class::lateStaticField1, "Read value from uninitialized Class.lateStaticField1");
+  self::Class::lateStaticField1 = 87;
+  self::expect(87, self::Class::lateStaticField1);
+  self::Class::staticMethod();
+  self::throws(() → core::int? => self::Extension|lateExtensionField1, "Read value from uninitialized Extension.lateExtensionField1");
+  self::Extension|lateExtensionField1 = 87;
+  self::expect(87, self::Extension|lateExtensionField1);
+  self::Extension|staticMethod();
+  new self::Class::•<core::int?>().{self::Class::instanceMethod}(null){(core::int?) → dynamic};
+  new self::Class::•<core::int?>().{self::Class::instanceMethod}(0){(core::int?) → dynamic};
+  new self::Class::•<core::int>().{self::Class::instanceMethod}(null){(core::int?) → dynamic};
+  new self::Class::•<core::int>().{self::Class::instanceMethod}(0){(core::int?) → dynamic};
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_nullable_local_with_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_nullable_local_with_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..a150002
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_nullable_local_with_initializer.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method lateLocalInit() → core::int?
+  return 123;
+static method main() → dynamic {
+  lowered core::int? #lateLocal;
+  lowered core::bool #lateLocal#isSet = false;
+  function #lateLocal#get() → core::int? {
+    if(!#lateLocal#isSet) {
+      #lateLocal = self::lateLocalInit();
+      #lateLocal#isSet = true;
+    }
+    return #lateLocal;
+  }
+  function #lateLocal#set(core::int? #t1) → dynamic {
+    #lateLocal#isSet = true;
+    return #lateLocal = #t1;
+  }
+  self::expect(123, #lateLocal#get(){() → core::int?});
+  self::expect(124, #lateLocal#set(124){(core::int?) → dynamic});
+  self::expect(124, #lateLocal#get(){() → core::int?});
+  function local<T extends core::Object? = dynamic>(T? value1, T? value2) → Null {
+    lowered T? #lateGenericLocal;
+    lowered core::bool #lateGenericLocal#isSet = false;
+    function #lateGenericLocal#get() → T? {
+      if(!#lateGenericLocal#isSet) {
+        #lateGenericLocal = value1;
+        #lateGenericLocal#isSet = true;
+      }
+      return #lateGenericLocal;
+    }
+    function #lateGenericLocal#set(T? #t2) → dynamic {
+      #lateGenericLocal#isSet = true;
+      return #lateGenericLocal = #t2;
+    }
+    self::expect(value1, #lateGenericLocal#get(){() → T?});
+    self::expect(value2, #lateGenericLocal#set(value2){(T?) → dynamic});
+    self::expect(value2, #lateGenericLocal#get(){() → T?});
+  }
+  local<core::int?>(null, 0){(core::int?, core::int?) → Null};
+  local<core::int?>(0, null){(core::int?, core::int?) → Null};
+  local<core::int>(null, 0){(core::int?, core::int?) → Null};
+  local<core::int>(0, null){(core::int?, core::int?) → Null};
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_nullable_local_without_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_nullable_local_without_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..133710a
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_nullable_local_without_initializer.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+static method main() → dynamic {
+  lowered core::int? #lateLocal;
+  lowered core::bool #lateLocal#isSet = false;
+  function #lateLocal#get() → core::int?
+    return #lateLocal#isSet ?{core::int?} #lateLocal : throw new _in::LateError::localNI("lateLocal");
+  function #lateLocal#set(core::int? #t1) → dynamic {
+    #lateLocal#isSet = true;
+    return #lateLocal = #t1;
+  }
+  self::throws(() → core::int? => #lateLocal#get(){() → core::int?}, "Read value from uninitialized lateLocal");
+  self::expect(123, #lateLocal#set(123){(core::int?) → dynamic});
+  self::expect(123, #lateLocal#get(){() → core::int?});
+  function local<T extends core::Object? = dynamic>(T? value) → Null {
+    lowered T? #lateGenericLocal;
+    lowered core::bool #lateGenericLocal#isSet = false;
+    function #lateGenericLocal#get() → T?
+      return #lateGenericLocal#isSet ?{T?} #lateGenericLocal : throw new _in::LateError::localNI("lateGenericLocal");
+    function #lateGenericLocal#set(T? #t2) → dynamic {
+      #lateGenericLocal#isSet = true;
+      return #lateGenericLocal = #t2;
+    }
+    self::throws(() → T? => #lateGenericLocal#get(){() → T?}, "Read value from uninitialized lateGenericLocal");
+    self::expect(value, #lateGenericLocal#set(value){(T?) → dynamic});
+    self::expect(value, #lateGenericLocal#get(){() → T?});
+  }
+  local<core::int?>(null){(core::int?) → Null};
+  local<core::int?>(0){(core::int?) → Null};
+  local<core::int>(null){(core::int?) → Null};
+  local<core::int>(0){(core::int?) → Null};
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/late_override.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/late_override.dart.weak.modular.expect
new file mode 100644
index 0000000..bb99080
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/late_override.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Interface extends core::Object {
+  field core::int? _#Interface#implementedLateFieldDeclaredGetterSetter = null;
+  field core::bool _#Interface#implementedLateFieldDeclaredGetterSetter#isSet = false;
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  get implementedLateFieldDeclaredGetterSetter() → core::int
+    return this.{self::Interface::_#Interface#implementedLateFieldDeclaredGetterSetter#isSet}{core::bool} ?{core::int} let final core::int? #t1 = this.{self::Interface::_#Interface#implementedLateFieldDeclaredGetterSetter}{core::int?} in #t1{core::int} : throw new _in::LateError::fieldNI("implementedLateFieldDeclaredGetterSetter");
+  set implementedLateFieldDeclaredGetterSetter(core::int #t2) → void {
+    this.{self::Interface::_#Interface#implementedLateFieldDeclaredGetterSetter#isSet} = true;
+    this.{self::Interface::_#Interface#implementedLateFieldDeclaredGetterSetter} = #t2;
+  }
+}
+class Class extends core::Object implements self::Interface {
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  get implementedLateFieldDeclaredGetterSetter() → core::int
+    return 0;
+  set implementedLateFieldDeclaredGetterSetter(core::int value) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/late_lowering/later.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/later.dart.weak.modular.expect
new file mode 100644
index 0000000..a38e25a
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/later.dart.weak.modular.expect
@@ -0,0 +1,208 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/late_lowering/later.dart:14:7: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   foo(late int x) {} // Error.
+//       ^^^^
+//
+// pkg/front_end/testcases/late_lowering/later.dart:17:5: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+// bar(late int x) {} // Error.
+//     ^^^^
+//
+// pkg/front_end/testcases/late_lowering/later.dart:22:28: Error: 'catch' must be followed by '(identifier)' or '(identifier, identifier)'.
+// No types are needed, the first is given by 'on', the second is always 'StackTrace'.
+//   } on dynamic catch (late e, late t) {} // Error.
+//                            ^
+//
+// pkg/front_end/testcases/late_lowering/later.dart:22:31: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   } on dynamic catch (late e, late t) {} // Error.
+//                               ^^^^
+//
+// pkg/front_end/testcases/late_lowering/later.dart:22:36: Error: 'catch' must be followed by '(identifier)' or '(identifier, identifier)'.
+// No types are needed, the first is given by 'on', the second is always 'StackTrace'.
+//   } on dynamic catch (late e, late t) {} // Error.
+//                                    ^
+//
+// pkg/front_end/testcases/late_lowering/later.dart:23:8: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   for (late int i = 0; i < 10; ++i) { // Error.
+//        ^^^^
+//
+// pkg/front_end/testcases/late_lowering/later.dart:26:8: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   for (late String s in ["baz"]) { // Error.
+//        ^^^^
+//
+// pkg/front_end/testcases/late_lowering/later.dart:29:9: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   [for (late int i = 0; i < 10; ++i) i]; // Error.
+//         ^^^^
+//
+// pkg/front_end/testcases/late_lowering/later.dart:33:14: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   await for (late String s in new Stream.fromIterable(["hest"])) { // Error.
+//              ^^^^
+//
+// pkg/front_end/testcases/late_lowering/later.dart:40:20: Error: `await` expressions are not supported in late local initializers.
+//   late String s1 = await hest(); // Error.
+//                    ^^^^^
+//
+// pkg/front_end/testcases/late_lowering/later.dart:41:30: Error: `await` expressions are not supported in late local initializers.
+//   late String s2 = '${fisk}${await hest()}${fisk}'; // Error.
+//                              ^^^^^
+//
+// pkg/front_end/testcases/late_lowering/later.dart:46:18: Error: Can't have a late final field in a class with a const constructor.
+//   late final int x = 42;
+//                  ^
+// pkg/front_end/testcases/late_lowering/later.dart:48:9: Context: This constructor is const.
+//   const B(); // Error: B has late final fields.
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+import "dart:async" as asy;
+
+class A extends core::Object {
+  field core::int a = 42;
+  field core::int? _#A#b = null;
+  field core::bool _#A#b#isSet = false;
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  get b() → core::int {
+    if(!this.{self::A::_#A#b#isSet}{core::bool}) {
+      this.{self::A::_#A#b} = this.{self::A::a}{core::int}.{core::num::*}(2){(core::num) → core::int}.{core::int::>>}(1){(core::int) → core::int};
+      this.{self::A::_#A#b#isSet} = true;
+    }
+    return let final core::int? #t1 = this.{self::A::_#A#b}{core::int?} in #t1{core::int};
+  }
+  set b(core::int #t2) → void {
+    this.{self::A::_#A#b#isSet} = true;
+    this.{self::A::_#A#b} = #t2;
+  }
+  method foo(core::int x) → dynamic {}
+}
+class B extends core::Object /*hasConstConstructor*/  {
+  field core::int? _#B#x = null;
+  field core::bool _#B#x#isSet = false;
+  const constructor •() → self::B
+    : super core::Object::•()
+    ;
+  get x() → core::int {
+    if(!this.{self::B::_#B#x#isSet}{core::bool}) {
+      final core::int #t3 = 42;
+      if(this.{self::B::_#B#x#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("x");
+      this.{self::B::_#B#x} = #t3;
+      this.{self::B::_#B#x#isSet} = true;
+    }
+    return let final core::int? #t4 = this.{self::B::_#B#x}{core::int?} in #t4{core::int};
+  }
+}
+class C extends core::Object {
+  field core::int? _#C#x = null;
+  field core::bool _#C#x#isSet = false;
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  get x() → core::int
+    return this.{self::C::_#C#x#isSet}{core::bool} ?{core::int} let final core::int? #t5 = this.{self::C::_#C#x}{core::int?} in #t5{core::int} : throw new _in::LateError::fieldNI("x");
+  set x(core::int #t6) → void
+    if(this.{self::C::_#C#x#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("x");
+    else {
+      this.{self::C::_#C#x#isSet} = true;
+      this.{self::C::_#C#x} = #t6;
+    }
+  method initVars() → dynamic {
+    this.{self::C::x} = 42;
+  }
+}
+static method bar(core::int x) → dynamic {}
+static method baz() → dynamic {
+  {
+    {
+      invalid-expression "pkg/front_end/testcases/late_lowering/later.dart:22:36: Error: 'catch' must be followed by '(identifier)' or '(identifier, identifier)'.
+No types are needed, the first is given by 'on', the second is always 'StackTrace'.
+  } on dynamic catch (late e, late t) {} // Error.
+                                   ^";
+    }
+    try {
+      throw "baz";
+    }
+    on dynamic catch(final dynamic late, final core::StackTrace e) {
+    }
+  }
+  for (core::int i = 0; i.{core::num::<}(10){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+    core::print("baz");
+  }
+  for (core::String s in <core::String>["baz"]) {
+    core::print(s);
+  }
+  block {
+    final core::List<core::int> #t7 = <core::int>[];
+    for (core::int i = 0; i.{core::num::<}(10){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int})
+      #t7.{core::List::add}{Invariant}(i){(core::int) → void};
+  } =>#t7;
+}
+static method hest() → dynamic async {
+  await for (core::String s in asy::Stream::fromIterable<core::String>(<core::String>["hest"])) {
+    core::print(s);
+  }
+  return "hest";
+}
+static method fisk() → dynamic async {
+  lowered core::String? #s1;
+  lowered core::bool #s1#isSet = false;
+  function #s1#get() → core::String {
+    if(!#s1#isSet) {
+      #s1 = invalid-expression "pkg/front_end/testcases/late_lowering/later.dart:40:20: Error: `await` expressions are not supported in late local initializers.
+  late String s1 = await hest(); // Error.
+                   ^^^^^";
+      #s1#isSet = true;
+    }
+    return #s1{core::String};
+  }
+  function #s1#set(core::String #t8) → dynamic {
+    #s1#isSet = true;
+    return #s1 = #t8;
+  }
+  lowered core::String? #s2;
+  lowered core::bool #s2#isSet = false;
+  function #s2#get() → core::String {
+    if(!#s2#isSet) {
+      #s2 = "${#C1}${invalid-expression "pkg/front_end/testcases/late_lowering/later.dart:41:30: Error: `await` expressions are not supported in late local initializers.
+  late String s2 = '\${fisk}\${await hest()}\${fisk}'; // Error.
+                             ^^^^^"}${#C1}";
+      #s2#isSet = true;
+    }
+    return #s2{core::String};
+  }
+  function #s2#set(core::String #t9) → dynamic {
+    #s2#isSet = true;
+    return #s2 = #t9;
+  }
+  lowered core::Function? #f;
+  lowered core::bool #f#isSet = false;
+  function #f#get() → core::Function {
+    if(!#f#isSet) {
+      #f = () → asy::Future<dynamic> async => await self::hest();
+      #f#isSet = true;
+    }
+    return #f{core::Function};
+  }
+  function #f#set(core::Function #t10) → dynamic {
+    #f#isSet = true;
+    return #f = #t10;
+  }
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::fisk
+}
diff --git a/pkg/front_end/testcases/late_lowering/non_nullable_from_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/non_nullable_from_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..86913df
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/non_nullable_from_opt_out.dart.weak.modular.expect
@@ -0,0 +1,183 @@
+library;
+import self as self;
+import "non_nullable_from_opt_out_lib.dart" as non;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///non_nullable_from_opt_out_lib.dart";
+
+static method main() → dynamic {
+  non::topLevelField = null;
+  non::finalTopLevelField = null;
+  non::Class<core::int*>* c = new non::Class::•<core::int*>();
+  c.{non::Class::instanceField} = null;
+  c.{non::Class::finalInstanceField} = null;
+  c.{non::Class::instanceTypeVariable} = null;
+  c.{non::Class::finalInstanceTypeVariable} = null;
+  non::Class::staticField = null;
+  non::Class::staticFinalField = null;
+  non::expect(null, non::topLevelField);
+  non::expect(null, non::finalTopLevelField);
+  non::expect(null, c.{non::Class::instanceField}{core::int*});
+  non::expect(null, c.{non::Class::finalInstanceField}{dynamic});
+  non::expect(null, c.{non::Class::instanceTypeVariable}{core::int*});
+  non::expect(null, c.{non::Class::finalInstanceTypeVariable}{core::int*});
+  non::expect(null, non::Class::staticField);
+  non::expect(null, non::Class::staticFinalField);
+  non::throws(() → Null => non::finalTopLevelField = null);
+  non::throws(() → Null => c.{non::Class::finalInstanceField} = null);
+  non::throws(() → Null => c.{non::Class::finalInstanceTypeVariable} = null);
+  non::throws(() → Null => non::Class::staticFinalField = null);
+  non::method<Null>(true, null, null);
+}
+
+library /*isNonNullableByDefault*/;
+import self as non;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class<T extends core::Object> extends core::Object {
+  field core::int? _#Class#instanceField = null;
+  field core::bool _#Class#instanceField#isSet = false;
+  field dynamic _#Class#finalInstanceField = null;
+  field core::bool _#Class#finalInstanceField#isSet = false;
+  covariant-by-class field non::Class::T? _#Class#instanceTypeVariable = null;
+  field core::bool _#Class#instanceTypeVariable#isSet = false;
+  field non::Class::T? _#Class#finalInstanceTypeVariable = null;
+  field core::bool _#Class#finalInstanceTypeVariable#isSet = false;
+  static field core::int? _#staticField = null;
+  static field core::bool _#staticField#isSet = false;
+  static field dynamic _#staticFinalField = null;
+  static field core::bool _#staticFinalField#isSet = false;
+  synthetic constructor •() → non::Class<non::Class::T>
+    : super core::Object::•()
+    ;
+  get instanceField() → core::int
+    return this.{non::Class::_#Class#instanceField#isSet}{core::bool} ?{core::int} let final core::int? #t1 = this.{non::Class::_#Class#instanceField}{core::int?} in #t1{core::int} : throw new _in::LateError::fieldNI("instanceField");
+  set instanceField(core::int #t2) → void {
+    this.{non::Class::_#Class#instanceField#isSet} = true;
+    this.{non::Class::_#Class#instanceField} = #t2;
+  }
+  get finalInstanceField() → dynamic
+    return this.{non::Class::_#Class#finalInstanceField#isSet}{core::bool} ?{dynamic} this.{non::Class::_#Class#finalInstanceField}{dynamic} : throw new _in::LateError::fieldNI("finalInstanceField");
+  set finalInstanceField(dynamic #t3) → void
+    if(this.{non::Class::_#Class#finalInstanceField#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("finalInstanceField");
+    else {
+      this.{non::Class::_#Class#finalInstanceField#isSet} = true;
+      this.{non::Class::_#Class#finalInstanceField} = #t3;
+    }
+  get instanceTypeVariable() → non::Class::T
+    return this.{non::Class::_#Class#instanceTypeVariable#isSet}{core::bool} ?{non::Class::T} let final non::Class::T? #t4 = this.{non::Class::_#Class#instanceTypeVariable}{non::Class::T?} in #t4{non::Class::T} : throw new _in::LateError::fieldNI("instanceTypeVariable");
+  set instanceTypeVariable(covariant-by-class non::Class::T #t5) → void {
+    this.{non::Class::_#Class#instanceTypeVariable#isSet} = true;
+    this.{non::Class::_#Class#instanceTypeVariable} = #t5;
+  }
+  get finalInstanceTypeVariable() → non::Class::T
+    return this.{non::Class::_#Class#finalInstanceTypeVariable#isSet}{core::bool} ?{non::Class::T} let final non::Class::T? #t6 = this.{non::Class::_#Class#finalInstanceTypeVariable}{non::Class::T?} in #t6{non::Class::T} : throw new _in::LateError::fieldNI("finalInstanceTypeVariable");
+  set finalInstanceTypeVariable(non::Class::T #t7) → void
+    if(this.{non::Class::_#Class#finalInstanceTypeVariable#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("finalInstanceTypeVariable");
+    else {
+      this.{non::Class::_#Class#finalInstanceTypeVariable#isSet} = true;
+      this.{non::Class::_#Class#finalInstanceTypeVariable} = #t7;
+    }
+  static get staticField() → core::int
+    return non::Class::_#staticField#isSet ?{core::int} let final core::int? #t8 = non::Class::_#staticField in #t8{core::int} : throw new _in::LateError::fieldNI("staticField");
+  static set staticField(core::int #t9) → void {
+    non::Class::_#staticField#isSet = true;
+    non::Class::_#staticField = #t9;
+  }
+  static get staticFinalField() → dynamic
+    return non::Class::_#staticFinalField#isSet ?{dynamic} non::Class::_#staticFinalField : throw new _in::LateError::fieldNI("staticFinalField");
+  static set staticFinalField(dynamic #t10) → void
+    if(non::Class::_#staticFinalField#isSet)
+      throw new _in::LateError::fieldAI("staticFinalField");
+    else {
+      non::Class::_#staticFinalField#isSet = true;
+      non::Class::_#staticFinalField = #t10;
+    }
+}
+static field core::int? _#topLevelField = null;
+static field core::bool _#topLevelField#isSet = false;
+static field dynamic _#finalTopLevelField = null;
+static field core::bool _#finalTopLevelField#isSet = false;
+static get topLevelField() → core::int
+  return non::_#topLevelField#isSet ?{core::int} let final core::int? #t11 = non::_#topLevelField in #t11{core::int} : throw new _in::LateError::fieldNI("topLevelField");
+static set topLevelField(core::int #t12) → void {
+  non::_#topLevelField#isSet = true;
+  non::_#topLevelField = #t12;
+}
+static get finalTopLevelField() → dynamic
+  return non::_#finalTopLevelField#isSet ?{dynamic} non::_#finalTopLevelField : throw new _in::LateError::fieldNI("finalTopLevelField");
+static set finalTopLevelField(dynamic #t13) → void
+  if(non::_#finalTopLevelField#isSet)
+    throw new _in::LateError::fieldAI("finalTopLevelField");
+  else {
+    non::_#finalTopLevelField#isSet = true;
+    non::_#finalTopLevelField = #t13;
+  }
+static method method<T extends core::Object>(core::bool b, core::int i, non::method::T t) → dynamic {
+  lowered core::int? #local;
+  lowered core::bool #local#isSet = false;
+  function #local#get() → core::int
+    return #local#isSet ?{core::int} #local{core::int} : throw new _in::LateError::localNI("local");
+  function #local#set(core::int #t14) → dynamic {
+    #local#isSet = true;
+    return #local = #t14;
+  }
+  lowered final dynamic #finalLocal;
+  lowered core::bool #finalLocal#isSet = false;
+  function #finalLocal#get() → dynamic
+    return #finalLocal#isSet ?{dynamic} #finalLocal : throw new _in::LateError::localNI("finalLocal");
+  function #finalLocal#set(dynamic #t15) → dynamic
+    if(#finalLocal#isSet)
+      throw new _in::LateError::localAI("finalLocal");
+    else {
+      #finalLocal#isSet = true;
+      return #finalLocal = #t15;
+    }
+  lowered non::method::T? #localTypeVariable;
+  lowered core::bool #localTypeVariable#isSet = false;
+  function #localTypeVariable#get() → non::method::T
+    return #localTypeVariable#isSet ?{non::method::T} #localTypeVariable{non::method::T} : throw new _in::LateError::localNI("localTypeVariable");
+  function #localTypeVariable#set(non::method::T #t16) → dynamic {
+    #localTypeVariable#isSet = true;
+    return #localTypeVariable = #t16;
+  }
+  lowered final non::method::T? #finalLocalTypeVariable;
+  lowered core::bool #finalLocalTypeVariable#isSet = false;
+  function #finalLocalTypeVariable#get() → non::method::T
+    return #finalLocalTypeVariable#isSet ?{non::method::T} #finalLocalTypeVariable{non::method::T} : throw new _in::LateError::localNI("finalLocalTypeVariable");
+  function #finalLocalTypeVariable#set(non::method::T #t17) → dynamic
+    if(#finalLocalTypeVariable#isSet)
+      throw new _in::LateError::localAI("finalLocalTypeVariable");
+    else {
+      #finalLocalTypeVariable#isSet = true;
+      return #finalLocalTypeVariable = #t17;
+    }
+  if(b) {
+    #local#set(i){(core::int) → dynamic};
+    #finalLocal#set(i){(dynamic) → dynamic};
+    #localTypeVariable#set(t){(non::method::T) → dynamic};
+    #finalLocalTypeVariable#set(t){(non::method::T) → dynamic};
+    non::expect(i, #local#get(){() → core::int});
+    non::expect(i, #finalLocal#get(){() → dynamic});
+    non::expect(t, #localTypeVariable#get(){() → non::method::T});
+    non::expect(t, #finalLocalTypeVariable#get(){() → non::method::T});
+  }
+  non::throws(() → void => #finalLocal#set(i){(dynamic) → dynamic});
+  non::throws(() → void => #finalLocalTypeVariable#set(t){(non::method::T) → dynamic});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → void f) → dynamic {
+  try {
+    f(){() → void};
+  }
+  on core::Object catch(final core::Object _) {
+    return;
+  }
+  throw "Missing exception";
+}
diff --git a/pkg/front_end/testcases/late_lowering/override.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/override.dart.weak.modular.expect
new file mode 100644
index 0000000..d89b35a
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/override.dart.weak.modular.expect
@@ -0,0 +1,156 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class extends core::Object {
+  field core::int? _#Class#field1 = null;
+  field core::bool _#Class#field1#isSet = false;
+  field core::int? _#Class#field2 = null;
+  field core::bool _#Class#field2#isSet = false;
+  field core::int? _#Class#field3 = null;
+  field core::bool _#Class#field3#isSet = false;
+  field core::int? _#Class#field4 = null;
+  field core::bool _#Class#field4#isSet = false;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  get field1() → core::int
+    return this.{self::Class::_#Class#field1#isSet}{core::bool} ?{core::int} let final core::int? #t1 = this.{self::Class::_#Class#field1}{core::int?} in #t1{core::int} : throw new _in::LateError::fieldNI("field1");
+  set field1(core::int #t2) → void {
+    this.{self::Class::_#Class#field1#isSet} = true;
+    this.{self::Class::_#Class#field1} = #t2;
+  }
+  get field2() → core::int
+    return this.{self::Class::_#Class#field2#isSet}{core::bool} ?{core::int} let final core::int? #t3 = this.{self::Class::_#Class#field2}{core::int?} in #t3{core::int} : throw new _in::LateError::fieldNI("field2");
+  set field2(core::int #t4) → void {
+    this.{self::Class::_#Class#field2#isSet} = true;
+    this.{self::Class::_#Class#field2} = #t4;
+  }
+  get field3() → core::int
+    return this.{self::Class::_#Class#field3#isSet}{core::bool} ?{core::int} let final core::int? #t5 = this.{self::Class::_#Class#field3}{core::int?} in #t5{core::int} : throw new _in::LateError::fieldNI("field3");
+  set field3(core::int #t6) → void
+    if(this.{self::Class::_#Class#field3#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("field3");
+    else {
+      this.{self::Class::_#Class#field3#isSet} = true;
+      this.{self::Class::_#Class#field3} = #t6;
+    }
+  get field4() → core::int
+    return this.{self::Class::_#Class#field4#isSet}{core::bool} ?{core::int} let final core::int? #t7 = this.{self::Class::_#Class#field4}{core::int?} in #t7{core::int} : throw new _in::LateError::fieldNI("field4");
+  set field4(core::int #t8) → void
+    if(this.{self::Class::_#Class#field4#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("field4");
+    else {
+      this.{self::Class::_#Class#field4#isSet} = true;
+      this.{self::Class::_#Class#field4} = #t8;
+    }
+}
+class SubClass extends self::Class {
+  field core::int? _#SubClass#field1 = null;
+  field core::bool _#SubClass#field1#isSet = false;
+  field core::int? _#SubClass#field2 = null;
+  field core::bool _#SubClass#field2#isSet = false;
+  field core::int? _#SubClass#field3 = null;
+  field core::bool _#SubClass#field3#isSet = false;
+  field core::int? _#SubClass#field4 = null;
+  field core::bool _#SubClass#field4#isSet = false;
+  synthetic constructor •() → self::SubClass
+    : super self::Class::•()
+    ;
+  get field1() → core::int
+    return this.{self::SubClass::_#SubClass#field1#isSet}{core::bool} ?{core::int} let final core::int? #t9 = this.{self::SubClass::_#SubClass#field1}{core::int?} in #t9{core::int} : throw new _in::LateError::fieldNI("field1");
+  set field1(core::int #t10) → void {
+    this.{self::SubClass::_#SubClass#field1#isSet} = true;
+    this.{self::SubClass::_#SubClass#field1} = #t10;
+  }
+  get field2() → core::int {
+    if(!this.{self::SubClass::_#SubClass#field2#isSet}{core::bool}) {
+      this.{self::SubClass::_#SubClass#field2} = 0;
+      this.{self::SubClass::_#SubClass#field2#isSet} = true;
+    }
+    return let final core::int? #t11 = this.{self::SubClass::_#SubClass#field2}{core::int?} in #t11{core::int};
+  }
+  set field2(core::int #t12) → void {
+    this.{self::SubClass::_#SubClass#field2#isSet} = true;
+    this.{self::SubClass::_#SubClass#field2} = #t12;
+  }
+  get field3() → core::int
+    return this.{self::SubClass::_#SubClass#field3#isSet}{core::bool} ?{core::int} let final core::int? #t13 = this.{self::SubClass::_#SubClass#field3}{core::int?} in #t13{core::int} : throw new _in::LateError::fieldNI("field3");
+  set field3(core::int #t14) → void
+    if(this.{self::SubClass::_#SubClass#field3#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("field3");
+    else {
+      this.{self::SubClass::_#SubClass#field3#isSet} = true;
+      this.{self::SubClass::_#SubClass#field3} = #t14;
+    }
+  get field4() → core::int {
+    if(!this.{self::SubClass::_#SubClass#field4#isSet}{core::bool}) {
+      final core::int #t15 = 0;
+      if(this.{self::SubClass::_#SubClass#field4#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("field4");
+      this.{self::SubClass::_#SubClass#field4} = #t15;
+      this.{self::SubClass::_#SubClass#field4#isSet} = true;
+    }
+    return let final core::int? #t16 = this.{self::SubClass::_#SubClass#field4}{core::int?} in #t16{core::int};
+  }
+  get directField1() → core::int
+    return super.{self::Class::field1};
+  set directField1(core::int value) → void {
+    super.{self::Class::field1} = value;
+  }
+  get directField2() → core::int
+    return super.{self::Class::field2};
+  set directField2(core::int value) → void {
+    super.{self::Class::field2} = value;
+  }
+  get directField3() → core::int
+    return super.{self::Class::field3};
+  get directField4() → core::int
+    return super.{self::Class::field4};
+}
+static method main() → dynamic {
+  self::SubClass sc = new self::SubClass::•();
+  self::Class c = sc;
+  self::throws(() → core::int => c.{self::Class::field1}{core::int}, "Read value from uninitialized SubClass.field1");
+  self::throws(() → core::int => sc.{self::SubClass::directField1}{core::int}, "Read value from uninitialized Class.field1");
+  self::expect(42, c.{self::Class::field1} = 42);
+  self::expect(42, c.{self::Class::field1}{core::int});
+  self::throws(() → core::int => sc.{self::SubClass::directField1}{core::int}, "Read value from uninitialized Class.field1");
+  self::expect(87, sc.{self::SubClass::directField1} = 87);
+  self::expect(87, sc.{self::SubClass::directField1}{core::int});
+  self::expect(0, c.{self::Class::field2}{core::int});
+  self::throws(() → core::int => sc.{self::SubClass::directField2}{core::int}, "Read value from uninitialized Class.field2");
+  self::expect(42, c.{self::Class::field2} = 42);
+  self::expect(42, c.{self::Class::field2}{core::int});
+  self::throws(() → core::int => sc.{self::SubClass::directField2}{core::int}, "Read value from uninitialized Class.field2");
+  self::expect(87, sc.{self::SubClass::directField2} = 87);
+  self::expect(87, sc.{self::SubClass::directField2}{core::int});
+  self::throws(() → core::int => c.{self::Class::field3}{core::int}, "Read value from uninitialized SubClass.field3");
+  self::throws(() → core::int => sc.{self::SubClass::directField3}{core::int}, "Read value from uninitialized Class.field3");
+  self::expect(42, c.{self::Class::field3} = 42);
+  self::expect(42, c.{self::Class::field3}{core::int});
+  self::throws(() → core::int => sc.{self::SubClass::directField3}{core::int}, "Read value from uninitialized Class.field3");
+  self::throws(() → core::int => c.{self::Class::field3} = 87, "Write value to initialized SubClass.field3");
+  self::expect(0, c.{self::Class::field4}{core::int});
+  self::throws(() → core::int => sc.{self::SubClass::directField4}{core::int}, "Read value from uninitialized Class.field4");
+  self::expect(42, c.{self::Class::field4} = 42);
+  self::expect(0, c.{self::Class::field4}{core::int});
+  self::expect(42, sc.{self::SubClass::directField4}{core::int});
+  self::throws(() → core::int => c.{self::Class::field4} = 87, "Write value to initialized SubClass.field4");
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}.";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/override_getter_setter.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/override_getter_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..e46b981
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/override_getter_setter.dart.weak.modular.expect
@@ -0,0 +1,101 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class A extends core::Object {
+  field core::int? _#A#x = null;
+  field core::bool _#A#x#isSet = false;
+  field core::int? _#A#y = null;
+  field core::bool _#A#y#isSet = false;
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  get x() → core::int
+    return this.{self::A::_#A#x#isSet}{core::bool} ?{core::int} let final core::int? #t1 = this.{self::A::_#A#x}{core::int?} in #t1{core::int} : throw new _in::LateError::fieldNI("x");
+  set x(core::int #t2) → void
+    if(this.{self::A::_#A#x#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("x");
+    else {
+      this.{self::A::_#A#x#isSet} = true;
+      this.{self::A::_#A#x} = #t2;
+    }
+  get y() → core::int?
+    return this.{self::A::_#A#y#isSet}{core::bool} ?{core::int?} this.{self::A::_#A#y}{core::int?} : throw new _in::LateError::fieldNI("y");
+  set y(core::int? #t3) → void
+    if(this.{self::A::_#A#y#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("y");
+    else {
+      this.{self::A::_#A#y#isSet} = true;
+      this.{self::A::_#A#y} = #t3;
+    }
+}
+class B extends self::A {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+  get x() → core::int
+    return 1;
+  get y() → core::int?
+    return 1;
+}
+class C extends self::A {
+  field core::int? _#C#x = null;
+  field core::bool _#C#x#isSet = false;
+  field core::int? _#C#y = null;
+  field core::bool _#C#y#isSet = false;
+  synthetic constructor •() → self::C
+    : super self::A::•()
+    ;
+  get x() → core::int {
+    if(!this.{self::C::_#C#x#isSet}{core::bool}) {
+      final core::int #t4 = 2;
+      if(this.{self::C::_#C#x#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("x");
+      this.{self::C::_#C#x} = #t4;
+      this.{self::C::_#C#x#isSet} = true;
+    }
+    return let final core::int? #t5 = this.{self::C::_#C#x}{core::int?} in #t5{core::int};
+  }
+  get y() → core::int? {
+    if(!this.{self::C::_#C#y#isSet}{core::bool}) {
+      final core::int? #t6 = 2;
+      if(this.{self::C::_#C#y#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("y");
+      this.{self::C::_#C#y} = #t6;
+      this.{self::C::_#C#y#isSet} = true;
+    }
+    return this.{self::C::_#C#y}{core::int?};
+  }
+}
+static method main() → dynamic {
+  self::B b = new self::B::•();
+  b.{self::A::x} = 3;
+  self::C c = new self::C::•();
+  self::throws(() → core::int => b.{self::A::x} = 14, "Write to B.x");
+  c.{self::A::x} = 3;
+  self::throws(() → core::int => c.{self::A::x} = 14, "Write to C.x");
+  self::expect(1, b.{self::B::x}{core::int});
+  self::expect(2, c.{self::C::x}{core::int});
+  b.{self::A::y} = 3;
+  self::throws(() → core::int => b.{self::A::y} = 14, "Write to B.y");
+  c.{self::A::y} = 3;
+  self::throws(() → core::int => c.{self::A::y} = 14, "Write to C.y");
+  self::expect(1, b.{self::B::y}{core::int?});
+  self::expect(2, c.{self::C::y}{core::int?});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/private_members.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/private_members.dart.weak.modular.expect
new file mode 100644
index 0000000..10fbd90
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/private_members.dart.weak.modular.expect
@@ -0,0 +1,143 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+part private_members_part.dart;
+class _Class extends core::Object { // from org-dartlang-testcase:///private_members_part.dart
+  field core::int? _#_Class#_privateField1 = null;
+  field core::bool _#_Class#_privateField1#isSet = false;
+  field core::int? _#_Class#_privateField2 = null;
+  field core::bool _#_Class#_privateField2#isSet = false;
+  field core::int? _#_Class#_privateFinalField1 = null;
+  field core::bool _#_Class#_privateFinalField1#isSet = false;
+  field core::int? _#_Class#_privateFinalField2 = null;
+  field core::bool _#_Class#_privateFinalField2#isSet = false;
+  synthetic constructor •() → self::_Class
+    : super core::Object::•()
+    ;
+  get _privateField1() → core::int {
+    if(!this.{self::_Class::_#_Class#_privateField1#isSet}{core::bool}) {
+      this.{self::_Class::_#_Class#_privateField1} = 1;
+      this.{self::_Class::_#_Class#_privateField1#isSet} = true;
+    }
+    return let final core::int? #t1 = this.{self::_Class::_#_Class#_privateField1}{core::int?} in #t1{core::int};
+  }
+  set _privateField1(core::int #t2) → void {
+    this.{self::_Class::_#_Class#_privateField1#isSet} = true;
+    this.{self::_Class::_#_Class#_privateField1} = #t2;
+  }
+  get _privateField2() → core::int? {
+    if(!this.{self::_Class::_#_Class#_privateField2#isSet}{core::bool}) {
+      this.{self::_Class::_#_Class#_privateField2} = 1;
+      this.{self::_Class::_#_Class#_privateField2#isSet} = true;
+    }
+    return this.{self::_Class::_#_Class#_privateField2}{core::int?};
+  }
+  set _privateField2(core::int? #t3) → void {
+    this.{self::_Class::_#_Class#_privateField2#isSet} = true;
+    this.{self::_Class::_#_Class#_privateField2} = #t3;
+  }
+  get _privateFinalField1() → core::int {
+    if(!this.{self::_Class::_#_Class#_privateFinalField1#isSet}{core::bool}) {
+      this.{self::_Class::_#_Class#_privateFinalField1} = 1;
+      this.{self::_Class::_#_Class#_privateFinalField1#isSet} = true;
+    }
+    return let final core::int? #t4 = this.{self::_Class::_#_Class#_privateFinalField1}{core::int?} in #t4{core::int};
+  }
+  set _privateFinalField1(core::int #t5) → void {
+    this.{self::_Class::_#_Class#_privateFinalField1#isSet} = true;
+    this.{self::_Class::_#_Class#_privateFinalField1} = #t5;
+  }
+  get _privateFinalField2() → core::int? {
+    if(!this.{self::_Class::_#_Class#_privateFinalField2#isSet}{core::bool}) {
+      this.{self::_Class::_#_Class#_privateFinalField2} = 1;
+      this.{self::_Class::_#_Class#_privateFinalField2#isSet} = true;
+    }
+    return this.{self::_Class::_#_Class#_privateFinalField2}{core::int?};
+  }
+  set _privateFinalField2(core::int? #t6) → void {
+    this.{self::_Class::_#_Class#_privateFinalField2#isSet} = true;
+    this.{self::_Class::_#_Class#_privateFinalField2} = #t6;
+  }
+}
+extension _Extension on core::int { // from org-dartlang-testcase:///private_members_part.dart
+  static field _privateField1 = self::_#_Extension|_privateField1;
+  static field _privateField1 = self::_#_Extension|_privateField1#isSet;
+  static get _privateField1 = get self::_Extension|_privateField1;
+  static set _privateField1 = set self::_Extension|_privateField1;
+  static field _privateField2 = self::_#_Extension|_privateField2;
+  static field _privateField2 = self::_#_Extension|_privateField2#isSet;
+  static get _privateField2 = get self::_Extension|_privateField2;
+  static set _privateField2 = set self::_Extension|_privateField2;
+  static field _privateFinalField1 = self::_#_Extension|_privateFinalField1;
+  static field _privateFinalField1 = self::_#_Extension|_privateFinalField1#isSet;
+  static get _privateFinalField1 = get self::_Extension|_privateFinalField1;
+  static set _privateFinalField1 = set self::_Extension|_privateFinalField1;
+  static field _privateFinalField2 = self::_#_Extension|_privateFinalField2;
+  static field _privateFinalField2 = self::_#_Extension|_privateFinalField2#isSet;
+  static get _privateFinalField2 = get self::_Extension|_privateFinalField2;
+  static set _privateFinalField2 = set self::_Extension|_privateFinalField2;
+}
+static field core::int? _#_Extension|_privateField1 = null /* from org-dartlang-testcase:///private_members_part.dart */;
+static field core::bool _#_Extension|_privateField1#isSet = false /* from org-dartlang-testcase:///private_members_part.dart */;
+static field core::int? _#_Extension|_privateField2 = null /* from org-dartlang-testcase:///private_members_part.dart */;
+static field core::bool _#_Extension|_privateField2#isSet = false /* from org-dartlang-testcase:///private_members_part.dart */;
+static field core::int? _#_Extension|_privateFinalField1 = null /* from org-dartlang-testcase:///private_members_part.dart */;
+static field core::bool _#_Extension|_privateFinalField1#isSet = false /* from org-dartlang-testcase:///private_members_part.dart */;
+static field core::int? _#_Extension|_privateFinalField2 = null /* from org-dartlang-testcase:///private_members_part.dart */;
+static field core::bool _#_Extension|_privateFinalField2#isSet = false /* from org-dartlang-testcase:///private_members_part.dart */;
+static method main() → dynamic {
+  self::_Class c = new self::_Class::•();
+  c.{self::_Class::_privateField1} = c.{self::_Class::_privateField1}{core::int};
+  c.{self::_Class::_privateField2} = c.{self::_Class::_privateField2}{core::int?};
+  c.{self::_Class::_privateFinalField1}{core::int};
+  c.{self::_Class::_privateFinalField2}{core::int?};
+  self::_Extension|_privateField1 = self::_Extension|_privateField1;
+  self::_Extension|_privateField2 = self::_Extension|_privateField2;
+  self::_Extension|_privateFinalField1;
+  self::_Extension|_privateFinalField2;
+}
+static get /* from org-dartlang-testcase:///private_members_part.dart */ _Extension|_privateField1() → core::int {
+  if(!self::_#_Extension|_privateField1#isSet) {
+    self::_#_Extension|_privateField1 = 1;
+    self::_#_Extension|_privateField1#isSet = true;
+  }
+  return let final core::int? #t7 = self::_#_Extension|_privateField1 in #t7{core::int};
+}
+static set /* from org-dartlang-testcase:///private_members_part.dart */ _Extension|_privateField1(core::int #t8) → void {
+  self::_#_Extension|_privateField1#isSet = true;
+  self::_#_Extension|_privateField1 = #t8;
+}
+static get /* from org-dartlang-testcase:///private_members_part.dart */ _Extension|_privateField2() → core::int? {
+  if(!self::_#_Extension|_privateField2#isSet) {
+    self::_#_Extension|_privateField2 = 1;
+    self::_#_Extension|_privateField2#isSet = true;
+  }
+  return self::_#_Extension|_privateField2;
+}
+static set /* from org-dartlang-testcase:///private_members_part.dart */ _Extension|_privateField2(core::int? #t9) → void {
+  self::_#_Extension|_privateField2#isSet = true;
+  self::_#_Extension|_privateField2 = #t9;
+}
+static get /* from org-dartlang-testcase:///private_members_part.dart */ _Extension|_privateFinalField1() → core::int {
+  if(!self::_#_Extension|_privateFinalField1#isSet) {
+    self::_#_Extension|_privateFinalField1 = 1;
+    self::_#_Extension|_privateFinalField1#isSet = true;
+  }
+  return let final core::int? #t10 = self::_#_Extension|_privateFinalField1 in #t10{core::int};
+}
+static set /* from org-dartlang-testcase:///private_members_part.dart */ _Extension|_privateFinalField1(core::int #t11) → void {
+  self::_#_Extension|_privateFinalField1#isSet = true;
+  self::_#_Extension|_privateFinalField1 = #t11;
+}
+static get /* from org-dartlang-testcase:///private_members_part.dart */ _Extension|_privateFinalField2() → core::int? {
+  if(!self::_#_Extension|_privateFinalField2#isSet) {
+    self::_#_Extension|_privateFinalField2 = 1;
+    self::_#_Extension|_privateFinalField2#isSet = true;
+  }
+  return self::_#_Extension|_privateFinalField2;
+}
+static set /* from org-dartlang-testcase:///private_members_part.dart */ _Extension|_privateFinalField2(core::int? #t12) → void {
+  self::_#_Extension|_privateFinalField2#isSet = true;
+  self::_#_Extension|_privateFinalField2 = #t12;
+}
diff --git a/pkg/front_end/testcases/late_lowering/return_late.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/return_late.dart.weak.modular.expect
new file mode 100644
index 0000000..3733586
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/return_late.dart.weak.modular.expect
@@ -0,0 +1,70 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Class<E extends core::Object? = dynamic> extends core::Object {
+  final field self::Class::E% field;
+  constructor •(self::Class::E% field) → self::Class<self::Class::E%>
+    : self::Class::field = field, super core::Object::•()
+    ;
+  method returnTypeVariable() → self::Class::E% {
+    lowered self::Class::E? #result;
+    lowered core::bool #result#isSet = false;
+    function #result#get() → self::Class::E% {
+      if(!#result#isSet) {
+        #result = this.{self::Class::field}{self::Class::E%};
+        #result#isSet = true;
+      }
+      return #result{self::Class::E%};
+    }
+    function #result#set(self::Class::E% #t1) → dynamic {
+      #result#isSet = true;
+      return #result = #t1;
+    }
+    return #result#get(){() → self::Class::E%};
+  }
+}
+static method returnNonNullable(core::int value) → core::int {
+  lowered core::int? #result;
+  lowered core::bool #result#isSet = false;
+  function #result#get() → core::int {
+    if(!#result#isSet) {
+      #result = value;
+      #result#isSet = true;
+    }
+    return #result{core::int};
+  }
+  function #result#set(core::int #t2) → dynamic {
+    #result#isSet = true;
+    return #result = #t2;
+  }
+  return #result#get(){() → core::int};
+}
+static method returnNullable(core::int? value) → core::int? {
+  lowered core::int? #result;
+  lowered core::bool #result#isSet = false;
+  function #result#get() → core::int? {
+    if(!#result#isSet) {
+      #result = value;
+      #result#isSet = true;
+    }
+    return #result;
+  }
+  function #result#set(core::int? #t3) → dynamic {
+    #result#isSet = true;
+    return #result = #t3;
+  }
+  return #result#get(){() → core::int?};
+}
+static method main() → dynamic {
+  self::expect(42, new self::Class::•<core::int>(42).{self::Class::returnTypeVariable}(){() → core::int});
+  self::expect(87, new self::Class::•<core::int?>(87).{self::Class::returnTypeVariable}(){() → core::int?});
+  self::expect(null, new self::Class::•<core::int?>(null).{self::Class::returnTypeVariable}(){() → core::int?});
+  self::expect(42, self::returnNonNullable(42));
+  self::expect(87, self::returnNullable(87));
+  self::expect(null, self::returnNullable(null));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/late_lowering/skip_late_final_uninitialized_instance_fields/main.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/skip_late_final_uninitialized_instance_fields/main.dart.weak.modular.expect
new file mode 100644
index 0000000..bfdde61
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/skip_late_final_uninitialized_instance_fields/main.dart.weak.modular.expect
@@ -0,0 +1,226 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class extends core::Object {
+  static field core::int? _#uninitializedNonFinalStaticField = null;
+  static field core::bool _#uninitializedNonFinalStaticField#isSet = false;
+  static field core::int? _#uninitializedFinalStaticField = null;
+  static field core::bool _#uninitializedFinalStaticField#isSet = false;
+  static field core::int? _#initializedNonFinalStaticField = null;
+  static field core::bool _#initializedNonFinalStaticField#isSet = false;
+  static field core::int? _#initializedFinalStaticField = null;
+  static field core::bool _#initializedFinalStaticField#isSet = false;
+  late field core::int uninitializedNonFinalInstanceField;
+  field core::int? _#Class#uninitializedFinalInstanceField = null;
+  field core::bool _#Class#uninitializedFinalInstanceField#isSet = false;
+  field core::int? _#Class#initializedNonFinalInstanceField = null;
+  field core::bool _#Class#initializedNonFinalInstanceField#isSet = false;
+  field core::int? _#Class#initializedFinalInstanceField = null;
+  field core::bool _#Class#initializedFinalInstanceField#isSet = false;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  static get uninitializedNonFinalStaticField() → core::int
+    return self::Class::_#uninitializedNonFinalStaticField#isSet ?{core::int} let final core::int? #t1 = self::Class::_#uninitializedNonFinalStaticField in #t1{core::int} : throw new _in::LateError::fieldNI("uninitializedNonFinalStaticField");
+  static set uninitializedNonFinalStaticField(core::int #t2) → void {
+    self::Class::_#uninitializedNonFinalStaticField#isSet = true;
+    self::Class::_#uninitializedNonFinalStaticField = #t2;
+  }
+  static get uninitializedFinalStaticField() → core::int
+    return self::Class::_#uninitializedFinalStaticField#isSet ?{core::int} let final core::int? #t3 = self::Class::_#uninitializedFinalStaticField in #t3{core::int} : throw new _in::LateError::fieldNI("uninitializedFinalStaticField");
+  static set uninitializedFinalStaticField(core::int #t4) → void
+    if(self::Class::_#uninitializedFinalStaticField#isSet)
+      throw new _in::LateError::fieldAI("uninitializedFinalStaticField");
+    else {
+      self::Class::_#uninitializedFinalStaticField#isSet = true;
+      self::Class::_#uninitializedFinalStaticField = #t4;
+    }
+  static get initializedNonFinalStaticField() → core::int {
+    if(!self::Class::_#initializedNonFinalStaticField#isSet) {
+      self::Class::_#initializedNonFinalStaticField = 0;
+      self::Class::_#initializedNonFinalStaticField#isSet = true;
+    }
+    return let final core::int? #t5 = self::Class::_#initializedNonFinalStaticField in #t5{core::int};
+  }
+  static set initializedNonFinalStaticField(core::int #t6) → void {
+    self::Class::_#initializedNonFinalStaticField#isSet = true;
+    self::Class::_#initializedNonFinalStaticField = #t6;
+  }
+  static get initializedFinalStaticField() → core::int {
+    if(!self::Class::_#initializedFinalStaticField#isSet) {
+      final core::int #t7 = 0;
+      if(self::Class::_#initializedFinalStaticField#isSet)
+        throw new _in::LateError::fieldADI("initializedFinalStaticField");
+      self::Class::_#initializedFinalStaticField = #t7;
+      self::Class::_#initializedFinalStaticField#isSet = true;
+    }
+    return let final core::int? #t8 = self::Class::_#initializedFinalStaticField in #t8{core::int};
+  }
+  get uninitializedFinalInstanceField() → core::int
+    return this.{self::Class::_#Class#uninitializedFinalInstanceField#isSet}{core::bool} ?{core::int} let final core::int? #t9 = this.{self::Class::_#Class#uninitializedFinalInstanceField}{core::int?} in #t9{core::int} : throw new _in::LateError::fieldNI("uninitializedFinalInstanceField");
+  set uninitializedFinalInstanceField(core::int #t10) → void
+    if(this.{self::Class::_#Class#uninitializedFinalInstanceField#isSet}{core::bool})
+      throw new _in::LateError::fieldAI("uninitializedFinalInstanceField");
+    else {
+      this.{self::Class::_#Class#uninitializedFinalInstanceField#isSet} = true;
+      this.{self::Class::_#Class#uninitializedFinalInstanceField} = #t10;
+    }
+  get initializedNonFinalInstanceField() → core::int {
+    if(!this.{self::Class::_#Class#initializedNonFinalInstanceField#isSet}{core::bool}) {
+      this.{self::Class::_#Class#initializedNonFinalInstanceField} = 0;
+      this.{self::Class::_#Class#initializedNonFinalInstanceField#isSet} = true;
+    }
+    return let final core::int? #t11 = this.{self::Class::_#Class#initializedNonFinalInstanceField}{core::int?} in #t11{core::int};
+  }
+  set initializedNonFinalInstanceField(core::int #t12) → void {
+    this.{self::Class::_#Class#initializedNonFinalInstanceField#isSet} = true;
+    this.{self::Class::_#Class#initializedNonFinalInstanceField} = #t12;
+  }
+  get initializedFinalInstanceField() → core::int {
+    if(!this.{self::Class::_#Class#initializedFinalInstanceField#isSet}{core::bool}) {
+      final core::int #t13 = 0;
+      if(this.{self::Class::_#Class#initializedFinalInstanceField#isSet}{core::bool})
+        throw new _in::LateError::fieldADI("initializedFinalInstanceField");
+      this.{self::Class::_#Class#initializedFinalInstanceField} = #t13;
+      this.{self::Class::_#Class#initializedFinalInstanceField#isSet} = true;
+    }
+    return let final core::int? #t14 = this.{self::Class::_#Class#initializedFinalInstanceField}{core::int?} in #t14{core::int};
+  }
+}
+static field core::int? _#uninitializedNonFinalTopLevelField = null;
+static field core::bool _#uninitializedNonFinalTopLevelField#isSet = false;
+static field core::int? _#uninitializedFinalTopLevelField = null;
+static field core::bool _#uninitializedFinalTopLevelField#isSet = false;
+static field core::int? _#initializedNonFinalTopLevelField = null;
+static field core::bool _#initializedNonFinalTopLevelField#isSet = false;
+static field core::int? _#initializedFinalTopLevelField = null;
+static field core::bool _#initializedFinalTopLevelField#isSet = false;
+static method main() → dynamic {}
+static method method() → dynamic {
+  lowered core::int? #nullableUninitializedNonFinalLocal;
+  lowered core::bool #nullableUninitializedNonFinalLocal#isSet = false;
+  function #nullableUninitializedNonFinalLocal#get() → core::int?
+    return #nullableUninitializedNonFinalLocal#isSet ?{core::int?} #nullableUninitializedNonFinalLocal : throw new _in::LateError::localNI("nullableUninitializedNonFinalLocal");
+  function #nullableUninitializedNonFinalLocal#set(core::int? #t15) → dynamic {
+    #nullableUninitializedNonFinalLocal#isSet = true;
+    return #nullableUninitializedNonFinalLocal = #t15;
+  }
+  lowered core::int? #nonNullableUninitializedNonFinalLocal;
+  lowered core::bool #nonNullableUninitializedNonFinalLocal#isSet = false;
+  function #nonNullableUninitializedNonFinalLocal#get() → core::int
+    return #nonNullableUninitializedNonFinalLocal#isSet ?{core::int} #nonNullableUninitializedNonFinalLocal{core::int} : throw new _in::LateError::localNI("nonNullableUninitializedNonFinalLocal");
+  function #nonNullableUninitializedNonFinalLocal#set(core::int #t16) → dynamic {
+    #nonNullableUninitializedNonFinalLocal#isSet = true;
+    return #nonNullableUninitializedNonFinalLocal = #t16;
+  }
+  lowered final core::int? #nullableUninitializedFinalLocal;
+  lowered core::bool #nullableUninitializedFinalLocal#isSet = false;
+  function #nullableUninitializedFinalLocal#get() → core::int?
+    return #nullableUninitializedFinalLocal#isSet ?{core::int?} #nullableUninitializedFinalLocal : throw new _in::LateError::localNI("nullableUninitializedFinalLocal");
+  function #nullableUninitializedFinalLocal#set(core::int? #t17) → dynamic
+    if(#nullableUninitializedFinalLocal#isSet)
+      throw new _in::LateError::localAI("nullableUninitializedFinalLocal");
+    else {
+      #nullableUninitializedFinalLocal#isSet = true;
+      return #nullableUninitializedFinalLocal = #t17;
+    }
+  lowered final core::int? #nonNullableUninitializedFinalLocal;
+  lowered core::bool #nonNullableUninitializedFinalLocal#isSet = false;
+  function #nonNullableUninitializedFinalLocal#get() → core::int
+    return #nonNullableUninitializedFinalLocal#isSet ?{core::int} #nonNullableUninitializedFinalLocal{core::int} : throw new _in::LateError::localNI("nonNullableUninitializedFinalLocal");
+  function #nonNullableUninitializedFinalLocal#set(core::int #t18) → dynamic
+    if(#nonNullableUninitializedFinalLocal#isSet)
+      throw new _in::LateError::localAI("nonNullableUninitializedFinalLocal");
+    else {
+      #nonNullableUninitializedFinalLocal#isSet = true;
+      return #nonNullableUninitializedFinalLocal = #t18;
+    }
+  lowered core::int? #nullableInitializedNonFinalLocal;
+  lowered core::bool #nullableInitializedNonFinalLocal#isSet = false;
+  function #nullableInitializedNonFinalLocal#get() → core::int? {
+    if(!#nullableInitializedNonFinalLocal#isSet) {
+      #nullableInitializedNonFinalLocal = 0;
+      #nullableInitializedNonFinalLocal#isSet = true;
+    }
+    return #nullableInitializedNonFinalLocal;
+  }
+  function #nullableInitializedNonFinalLocal#set(core::int? #t19) → dynamic {
+    #nullableInitializedNonFinalLocal#isSet = true;
+    return #nullableInitializedNonFinalLocal = #t19;
+  }
+  lowered core::int? #nonNullableInitializedNonFinalLocal;
+  lowered core::bool #nonNullableInitializedNonFinalLocal#isSet = false;
+  function #nonNullableInitializedNonFinalLocal#get() → core::int {
+    if(!#nonNullableInitializedNonFinalLocal#isSet) {
+      #nonNullableInitializedNonFinalLocal = 0;
+      #nonNullableInitializedNonFinalLocal#isSet = true;
+    }
+    return #nonNullableInitializedNonFinalLocal{core::int};
+  }
+  function #nonNullableInitializedNonFinalLocal#set(core::int #t20) → dynamic {
+    #nonNullableInitializedNonFinalLocal#isSet = true;
+    return #nonNullableInitializedNonFinalLocal = #t20;
+  }
+  lowered final core::int? #nullableInitializedFinalLocal;
+  lowered core::bool #nullableInitializedFinalLocal#isSet = false;
+  function #nullableInitializedFinalLocal#get() → core::int? {
+    if(!#nullableInitializedFinalLocal#isSet) {
+      final core::int? #t21 = 0;
+      if(#nullableInitializedFinalLocal#isSet)
+        throw new _in::LateError::localADI("nullableInitializedFinalLocal");
+      #nullableInitializedFinalLocal = #t21;
+      #nullableInitializedFinalLocal#isSet = true;
+    }
+    return #nullableInitializedFinalLocal;
+  }
+  lowered final core::int? #nonNullableInitializedFinalLocal;
+  lowered core::bool #nonNullableInitializedFinalLocal#isSet = false;
+  function #nonNullableInitializedFinalLocal#get() → core::int {
+    if(!#nonNullableInitializedFinalLocal#isSet) {
+      final core::int #t22 = 0;
+      if(#nonNullableInitializedFinalLocal#isSet)
+        throw new _in::LateError::localADI("nonNullableInitializedFinalLocal");
+      #nonNullableInitializedFinalLocal = #t22;
+      #nonNullableInitializedFinalLocal#isSet = true;
+    }
+    return #nonNullableInitializedFinalLocal{core::int};
+  }
+}
+static get uninitializedNonFinalTopLevelField() → core::int
+  return self::_#uninitializedNonFinalTopLevelField#isSet ?{core::int} let final core::int? #t23 = self::_#uninitializedNonFinalTopLevelField in #t23{core::int} : throw new _in::LateError::fieldNI("uninitializedNonFinalTopLevelField");
+static set uninitializedNonFinalTopLevelField(core::int #t24) → void {
+  self::_#uninitializedNonFinalTopLevelField#isSet = true;
+  self::_#uninitializedNonFinalTopLevelField = #t24;
+}
+static get uninitializedFinalTopLevelField() → core::int
+  return self::_#uninitializedFinalTopLevelField#isSet ?{core::int} let final core::int? #t25 = self::_#uninitializedFinalTopLevelField in #t25{core::int} : throw new _in::LateError::fieldNI("uninitializedFinalTopLevelField");
+static set uninitializedFinalTopLevelField(core::int #t26) → void
+  if(self::_#uninitializedFinalTopLevelField#isSet)
+    throw new _in::LateError::fieldAI("uninitializedFinalTopLevelField");
+  else {
+    self::_#uninitializedFinalTopLevelField#isSet = true;
+    self::_#uninitializedFinalTopLevelField = #t26;
+  }
+static get initializedNonFinalTopLevelField() → core::int {
+  if(!self::_#initializedNonFinalTopLevelField#isSet) {
+    self::_#initializedNonFinalTopLevelField = 0;
+    self::_#initializedNonFinalTopLevelField#isSet = true;
+  }
+  return let final core::int? #t27 = self::_#initializedNonFinalTopLevelField in #t27{core::int};
+}
+static set initializedNonFinalTopLevelField(core::int #t28) → void {
+  self::_#initializedNonFinalTopLevelField#isSet = true;
+  self::_#initializedNonFinalTopLevelField = #t28;
+}
+static get initializedFinalTopLevelField() → core::int {
+  if(!self::_#initializedFinalTopLevelField#isSet) {
+    final core::int #t29 = 0;
+    if(self::_#initializedFinalTopLevelField#isSet)
+      throw new _in::LateError::fieldADI("initializedFinalTopLevelField");
+    self::_#initializedFinalTopLevelField = #t29;
+    self::_#initializedFinalTopLevelField#isSet = true;
+  }
+  return let final core::int? #t30 = self::_#initializedFinalTopLevelField in #t30{core::int};
+}
diff --git a/pkg/front_end/testcases/late_lowering/uninitialized_non_nullable_late_fields.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering/uninitialized_non_nullable_late_fields.dart.weak.modular.expect
new file mode 100644
index 0000000..13fee7d
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering/uninitialized_non_nullable_late_fields.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class A extends core::Object {
+  field core::int? _#A#x = null;
+  field core::bool _#A#x#isSet = false;
+  constructor foo(core::int x) → self::A
+    : self::A::_#A#x#isSet = true, self::A::_#A#x = x, super core::Object::•()
+    ;
+  constructor bar() → self::A
+    : super core::Object::•()
+    ;
+  get x() → core::int
+    return this.{self::A::_#A#x#isSet}{core::bool} ?{core::int} let final core::int? #t1 = this.{self::A::_#A#x}{core::int?} in #t1{core::int} : throw new _in::LateError::fieldNI("x");
+  set x(core::int #t2) → void {
+    this.{self::A::_#A#x#isSet} = true;
+    this.{self::A::_#A#x} = #t2;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/late_lowering_sentinel/late_fields.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering_sentinel/late_fields.dart.weak.modular.expect
new file mode 100644
index 0000000..c037d72
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering_sentinel/late_fields.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+static field core::int? _#nullableTopLevelField = _in::createSentinel<core::int?>();
+static field core::int? _#nonNullableTopLevelField = _in::createSentinel<core::int>();
+static field core::int? _#nullableTopLevelFieldWithInitializer = _in::createSentinel<core::int?>();
+static field core::int? _#nonNullableTopLevelFieldWithInitializer = _in::createSentinel<core::int>();
+static field core::int? _#nullableFinalTopLevelField = _in::createSentinel<core::int?>();
+static field core::int? _#nonNullableFinalTopLevelField = _in::createSentinel<core::int>();
+static field core::int? _#nullableFinalTopLevelFieldWithInitializer = _in::createSentinel<core::int?>();
+static field core::int? _#nonNullableFinalTopLevelFieldWithInitializer = _in::createSentinel<core::int>();
+static field Never? _#neverTopLevelField = _in::createSentinel<Never>();
+static get nullableTopLevelField() → core::int?
+  return let final core::int? #t1 = self::_#nullableTopLevelField in _in::isSentinel(#t1) ?{core::int?} throw new _in::LateError::fieldNI("nullableTopLevelField") : #t1{core::int?};
+static set nullableTopLevelField(core::int? #t2) → void
+  self::_#nullableTopLevelField = #t2;
+static get nonNullableTopLevelField() → core::int
+  return let final core::int? #t3 = self::_#nonNullableTopLevelField in _in::isSentinel(#t3) ?{core::int} throw new _in::LateError::fieldNI("nonNullableTopLevelField") : #t3{core::int};
+static set nonNullableTopLevelField(core::int #t4) → void
+  self::_#nonNullableTopLevelField = #t4;
+static get nullableTopLevelFieldWithInitializer() → core::int?
+  return let final core::int? #t5 = self::_#nullableTopLevelFieldWithInitializer in _in::isSentinel(#t5) ?{core::int?} self::_#nullableTopLevelFieldWithInitializer = null : #t5{core::int?};
+static set nullableTopLevelFieldWithInitializer(core::int? #t6) → void
+  self::_#nullableTopLevelFieldWithInitializer = #t6;
+static get nonNullableTopLevelFieldWithInitializer() → core::int
+  return let final core::int? #t7 = self::_#nonNullableTopLevelFieldWithInitializer in _in::isSentinel(#t7) ?{core::int} self::_#nonNullableTopLevelFieldWithInitializer = 0 : #t7{core::int};
+static set nonNullableTopLevelFieldWithInitializer(core::int #t8) → void
+  self::_#nonNullableTopLevelFieldWithInitializer = #t8;
+static get nullableFinalTopLevelField() → core::int?
+  return let final core::int? #t9 = self::_#nullableFinalTopLevelField in _in::isSentinel(#t9) ?{core::int?} throw new _in::LateError::fieldNI("nullableFinalTopLevelField") : #t9{core::int?};
+static set nullableFinalTopLevelField(core::int? #t10) → void
+  if(_in::isSentinel(self::_#nullableFinalTopLevelField))
+    self::_#nullableFinalTopLevelField = #t10;
+  else
+    throw new _in::LateError::fieldAI("nullableFinalTopLevelField");
+static get nonNullableFinalTopLevelField() → core::int
+  return let final core::int? #t11 = self::_#nonNullableFinalTopLevelField in _in::isSentinel(#t11) ?{core::int} throw new _in::LateError::fieldNI("nonNullableFinalTopLevelField") : #t11{core::int};
+static set nonNullableFinalTopLevelField(core::int #t12) → void
+  if(_in::isSentinel(self::_#nonNullableFinalTopLevelField))
+    self::_#nonNullableFinalTopLevelField = #t12;
+  else
+    throw new _in::LateError::fieldAI("nonNullableFinalTopLevelField");
+static get nullableFinalTopLevelFieldWithInitializer() → core::int?
+  return let final core::int? #t13 = self::_#nullableFinalTopLevelFieldWithInitializer in _in::isSentinel(#t13) ?{core::int?} let final core::int? #t14 = null in _in::isSentinel(self::_#nullableFinalTopLevelFieldWithInitializer) ?{core::int?} self::_#nullableFinalTopLevelFieldWithInitializer = #t14 : throw new _in::LateError::fieldADI("nullableFinalTopLevelFieldWithInitializer") : #t13;
+static get nonNullableFinalTopLevelFieldWithInitializer() → core::int
+  return let final core::int #t15 = self::_#nonNullableFinalTopLevelFieldWithInitializer in _in::isSentinel(#t15) ?{core::int} let final core::int #t16 = 0 in _in::isSentinel(self::_#nonNullableFinalTopLevelFieldWithInitializer) ?{core::int} self::_#nonNullableFinalTopLevelFieldWithInitializer = #t16 : throw new _in::LateError::fieldADI("nonNullableFinalTopLevelFieldWithInitializer") : #t15;
+static get neverTopLevelField() → Never
+  return let final Never? #t17 = self::_#neverTopLevelField in _in::isSentinel(#t17) ?{Never} throw new _in::LateError::fieldNI("neverTopLevelField") : #t17{Never};
+static set neverTopLevelField(Never #t18) → void
+  self::_#neverTopLevelField = #t18;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/late_lowering_sentinel/late_locals.dart.weak.modular.expect b/pkg/front_end/testcases/late_lowering_sentinel/late_locals.dart.weak.modular.expect
new file mode 100644
index 0000000..98019ae
--- /dev/null
+++ b/pkg/front_end/testcases/late_lowering_sentinel/late_locals.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+static method test() → dynamic {
+  lowered core::int? #nullableTopLevelLocal = _in::createSentinel<core::int?>();
+  function #nullableTopLevelLocal#get() → core::int?
+    return let final core::int? #t1 = #nullableTopLevelLocal in _in::isSentinel(#t1) ?{core::int?} throw new _in::LateError::localNI("nullableTopLevelLocal") : #t1{core::int?};
+  function #nullableTopLevelLocal#set(core::int? #t2) → dynamic
+    return #nullableTopLevelLocal = #t2;
+  lowered core::int? #nonNullableTopLevelLocal = _in::createSentinel<core::int>();
+  function #nonNullableTopLevelLocal#get() → core::int
+    return let final core::int? #t3 = #nonNullableTopLevelLocal in _in::isSentinel(#t3) ?{core::int} throw new _in::LateError::localNI("nonNullableTopLevelLocal") : #t3{core::int};
+  function #nonNullableTopLevelLocal#set(core::int #t4) → dynamic
+    return #nonNullableTopLevelLocal = #t4;
+  lowered core::int? #nullableTopLevelLocalWithInitializer = _in::createSentinel<core::int?>();
+  function #nullableTopLevelLocalWithInitializer#get() → core::int?
+    return let final core::int? #t5 = #nullableTopLevelLocalWithInitializer in _in::isSentinel(#t5) ?{core::int?} #nullableTopLevelLocalWithInitializer = null : #t5{core::int?};
+  function #nullableTopLevelLocalWithInitializer#set(core::int? #t6) → dynamic
+    return #nullableTopLevelLocalWithInitializer = #t6;
+  lowered core::int? #nonNullableTopLevelLocalWithInitializer = _in::createSentinel<core::int>();
+  function #nonNullableTopLevelLocalWithInitializer#get() → core::int
+    return let final core::int? #t7 = #nonNullableTopLevelLocalWithInitializer in _in::isSentinel(#t7) ?{core::int} #nonNullableTopLevelLocalWithInitializer = 0 : #t7{core::int};
+  function #nonNullableTopLevelLocalWithInitializer#set(core::int #t8) → dynamic
+    return #nonNullableTopLevelLocalWithInitializer = #t8;
+  lowered final core::int? #nullableFinalTopLevelLocal = _in::createSentinel<core::int?>();
+  function #nullableFinalTopLevelLocal#get() → core::int?
+    return let final core::int? #t9 = #nullableFinalTopLevelLocal in _in::isSentinel(#t9) ?{core::int?} throw new _in::LateError::localNI("nullableFinalTopLevelLocal") : #t9{core::int?};
+  function #nullableFinalTopLevelLocal#set(core::int? #t10) → dynamic
+    if(_in::isSentinel(#nullableFinalTopLevelLocal))
+      return #nullableFinalTopLevelLocal = #t10;
+    else
+      throw new _in::LateError::localAI("nullableFinalTopLevelLocal");
+  lowered final core::int? #nonNullableFinalTopLevelLocal = _in::createSentinel<core::int>();
+  function #nonNullableFinalTopLevelLocal#get() → core::int
+    return let final core::int? #t11 = #nonNullableFinalTopLevelLocal in _in::isSentinel(#t11) ?{core::int} throw new _in::LateError::localNI("nonNullableFinalTopLevelLocal") : #t11{core::int};
+  function #nonNullableFinalTopLevelLocal#set(core::int #t12) → dynamic
+    if(_in::isSentinel(#nonNullableFinalTopLevelLocal))
+      return #nonNullableFinalTopLevelLocal = #t12;
+    else
+      throw new _in::LateError::localAI("nonNullableFinalTopLevelLocal");
+  lowered final core::int? #nullableFinalTopLevelLocalWithInitializer = _in::createSentinel<core::int?>();
+  function #nullableFinalTopLevelLocalWithInitializer#get() → core::int?
+    return let final core::int? #t13 = #nullableFinalTopLevelLocalWithInitializer in _in::isSentinel(#t13) ?{core::int?} let final core::int? #t14 = null in _in::isSentinel(#nullableFinalTopLevelLocalWithInitializer) ?{core::int?} #nullableFinalTopLevelLocalWithInitializer = #t14 : throw new _in::LateError::localADI("nullableFinalTopLevelLocalWithInitializer") : #t13;
+  lowered final core::int? #nonNullableFinalTopLevelLocalWithInitializer = _in::createSentinel<core::int>();
+  function #nonNullableFinalTopLevelLocalWithInitializer#get() → core::int
+    return let final core::int #t15 = #nonNullableFinalTopLevelLocalWithInitializer in _in::isSentinel(#t15) ?{core::int} let final core::int #t16 = 0 in _in::isSentinel(#nonNullableFinalTopLevelLocalWithInitializer) ?{core::int} #nonNullableFinalTopLevelLocalWithInitializer = #t16 : throw new _in::LateError::localADI("nonNullableFinalTopLevelLocalWithInitializer") : #t15;
+  lowered Null #neverLocal = _in::createSentinel<Never>();
+  function #neverLocal#get() → Never
+    return let final Never? #t17 = #neverLocal in _in::isSentinel(#t17) ?{Never} throw new _in::LateError::localNI("neverLocal") : #t17{Never};
+  function #neverLocal#set(Never #t18) → dynamic
+    return #neverLocal = #t18;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/macros/folder.options b/pkg/front_end/testcases/macros/folder.options
new file mode 100644
index 0000000..05bef8b
--- /dev/null
+++ b/pkg/front_end/testcases/macros/folder.options
@@ -0,0 +1 @@
+--enable-experiment=macros
\ No newline at end of file
diff --git a/pkg/front_end/testcases/macros/macro_class.dart b/pkg/front_end/testcases/macros/macro_class.dart
new file mode 100644
index 0000000..36ad13f
--- /dev/null
+++ b/pkg/front_end/testcases/macros/macro_class.dart
@@ -0,0 +1,13 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+class Super {}
+mixin Mixin {}
+
+macro class Class1 {}
+abstract macro class Class2 {}
+macro class Class3 = Super with Mixin;
+abstract macro class Class4 = Super with Mixin;
+
+main() {}
\ No newline at end of file
diff --git a/pkg/front_end/testcases/macros/macro_class.dart.strong.expect b/pkg/front_end/testcases/macros/macro_class.dart.strong.expect
new file mode 100644
index 0000000..d2dba25
--- /dev/null
+++ b/pkg/front_end/testcases/macros/macro_class.dart.strong.expect
@@ -0,0 +1,32 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+}
+macro class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+}
+abstract macro class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2
+    : super core::Object::•()
+    ;
+}
+macro class Class3 = self::Super with self::Mixin {
+  synthetic constructor •() → self::Class3
+    : super self::Super::•()
+    ;
+}
+abstract macro class Class4 = self::Super with self::Mixin {
+  synthetic constructor •() → self::Class4
+    : super self::Super::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/macros/macro_class.dart.strong.transformed.expect b/pkg/front_end/testcases/macros/macro_class.dart.strong.transformed.expect
new file mode 100644
index 0000000..d100b6c
--- /dev/null
+++ b/pkg/front_end/testcases/macros/macro_class.dart.strong.transformed.expect
@@ -0,0 +1,32 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+}
+macro class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+}
+abstract macro class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2
+    : super core::Object::•()
+    ;
+}
+macro class Class3 extends self::Super implements self::Mixin /*isEliminatedMixin*/  {
+  synthetic constructor •() → self::Class3
+    : super self::Super::•()
+    ;
+}
+abstract macro class Class4 extends self::Super implements self::Mixin /*isEliminatedMixin*/  {
+  synthetic constructor •() → self::Class4
+    : super self::Super::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/macros/macro_class.dart.textual_outline.expect b/pkg/front_end/testcases/macros/macro_class.dart.textual_outline.expect
new file mode 100644
index 0000000..d33df1d
--- /dev/null
+++ b/pkg/front_end/testcases/macros/macro_class.dart.textual_outline.expect
@@ -0,0 +1,9 @@
+class Super {}
+mixin Mixin {}
+macro
+class Class1 {}
+abstract macro class Class2 {}
+macro
+class Class3 = Super with Mixin;
+abstract macro class Class4 = Super with Mixin;
+main() {}
diff --git a/pkg/front_end/testcases/macros/macro_class.dart.weak.expect b/pkg/front_end/testcases/macros/macro_class.dart.weak.expect
new file mode 100644
index 0000000..d2dba25
--- /dev/null
+++ b/pkg/front_end/testcases/macros/macro_class.dart.weak.expect
@@ -0,0 +1,32 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+}
+macro class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+}
+abstract macro class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2
+    : super core::Object::•()
+    ;
+}
+macro class Class3 = self::Super with self::Mixin {
+  synthetic constructor •() → self::Class3
+    : super self::Super::•()
+    ;
+}
+abstract macro class Class4 = self::Super with self::Mixin {
+  synthetic constructor •() → self::Class4
+    : super self::Super::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/macros/macro_class.dart.weak.modular.expect b/pkg/front_end/testcases/macros/macro_class.dart.weak.modular.expect
new file mode 100644
index 0000000..d2dba25
--- /dev/null
+++ b/pkg/front_end/testcases/macros/macro_class.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+}
+macro class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+}
+abstract macro class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2
+    : super core::Object::•()
+    ;
+}
+macro class Class3 = self::Super with self::Mixin {
+  synthetic constructor •() → self::Class3
+    : super self::Super::•()
+    ;
+}
+abstract macro class Class4 = self::Super with self::Mixin {
+  synthetic constructor •() → self::Class4
+    : super self::Super::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/macros/macro_class.dart.weak.outline.expect b/pkg/front_end/testcases/macros/macro_class.dart.weak.outline.expect
new file mode 100644
index 0000000..ecf4712
--- /dev/null
+++ b/pkg/front_end/testcases/macros/macro_class.dart.weak.outline.expect
@@ -0,0 +1,30 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    ;
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+}
+macro class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    ;
+}
+abstract macro class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2
+    ;
+}
+macro class Class3 = self::Super with self::Mixin {
+  synthetic constructor •() → self::Class3
+    : super self::Super::•()
+    ;
+}
+abstract macro class Class4 = self::Super with self::Mixin {
+  synthetic constructor •() → self::Class4
+    : super self::Super::•()
+    ;
+}
+static method main() → dynamic
+  ;
diff --git a/pkg/front_end/testcases/macros/macro_class.dart.weak.transformed.expect b/pkg/front_end/testcases/macros/macro_class.dart.weak.transformed.expect
new file mode 100644
index 0000000..d100b6c
--- /dev/null
+++ b/pkg/front_end/testcases/macros/macro_class.dart.weak.transformed.expect
@@ -0,0 +1,32 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+}
+macro class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+}
+abstract macro class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2
+    : super core::Object::•()
+    ;
+}
+macro class Class3 extends self::Super implements self::Mixin /*isEliminatedMixin*/  {
+  synthetic constructor •() → self::Class3
+    : super self::Super::•()
+    ;
+}
+abstract macro class Class4 extends self::Super implements self::Mixin /*isEliminatedMixin*/  {
+  synthetic constructor •() → self::Class4
+    : super self::Super::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/modular.status b/pkg/front_end/testcases/modular.status
new file mode 100644
index 0000000..3d6a84f
--- /dev/null
+++ b/pkg/front_end/testcases/modular.status
@@ -0,0 +1,89 @@
+# Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+# for details. All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE.md file.
+
+# Status file for the modular_suite.dart test suite.
+
+constructor_tearoffs/call_instantiation: TypeCheckError
+constructor_tearoffs/lowering/invalid_redirect: VerificationError
+extension_types/access_setter_as_getter: ExpectationFileMismatchSerialized # Expected.
+extension_types/call_not_get: ExpectationFileMismatchSerialized # Expected.
+extension_types/extension_on_nullable: ExpectationFileMismatchSerialized # Expected.
+extension_types/issue45775: ExpectationFileMismatchSerialized # Expected.
+extension_types/show_and_run_ceil: ExpectationFileMismatchSerialized # Expected.
+extension_types/simple: ExpectationFileMismatchSerialized # Expected.
+extension_types/simple_getter_resolution: ExpectationFileMismatchSerialized # Expected.
+extension_types/simple_method_resolution: ExpectationFileMismatchSerialized # Expected.
+extension_types/simple_operator_resolution: ExpectationFileMismatchSerialized # Expected.
+extension_types/simple_setter_resolution: ExpectationFileMismatchSerialized # Expected.
+extension_types/simple_show_hide: ExpectationFileMismatchSerialized # Expected.
+extension_types/type_variable_in_static_context: ExpectationFileMismatchSerialized # Expected.
+extensions/extension_setter_error: TypeCheckError
+general/abstract_members: TypeCheckError
+general/bounded_implicit_instantiation: TypeCheckError
+general/bug30695: TypeCheckError
+general/covariant_field: TypeCheckError
+general/crashes/crash_02/main: Crash
+general/crashes/crash_06/main: Crash
+general/duplicated_declarations: TypeCheckError
+general/getter_vs_setter_type: TypeCheckError
+general/implement_semi_stub: TypeCheckError
+general/implicit_super_call: TypeCheckError
+general/infer_field_from_multiple: TypeCheckError
+general/invalid_operator: TypeCheckError
+general/invalid_operator_override: TypeCheckError
+general/issue41210a: TypeCheckError
+general/issue41210b/issue41210.no_link: TypeCheckError
+general/issue41210b/issue41210: TypeCheckError
+general/issue44733: TypeCheckError
+general/mixin_application_override: ExpectationFileMismatch # Too many errors.
+general/mixin_application_override: TypeCheckError
+general/override_check_accessor_after_inference: TypeCheckError # Issue #31620
+general/override_check_accessor_basic: TypeCheckError # Issue #31620
+general/override_check_accessor_with_covariant_modifier: TypeCheckError # Issue #31620
+general/override_check_after_inference: TypeCheckError # Issue #31620
+general/override_check_basic: TypeCheckError # Issue #31620
+general/override_check_with_covariant_modifier: TypeCheckError # Issue #31620
+general/override_setter_with_field: TypeCheckError
+general/redirecting_factory_invocation_in_invalid: TypeCheckError
+general/super_semi_stub: TypeCheckError
+general/unsound_promotion: TypeCheckError
+inference/constructors_infer_from_arguments_argument_not_assignable: TypeCheckError
+inference/do_not_infer_overridden_fields_that_explicitly_say_dynamic_infer: TypeCheckError
+inference/generic_methods_correctly_recognize_generic_upper_bound: TypeCheckError
+inference/generic_methods_do_not_infer_invalid_override_of_generic_method: TypeCheckError
+inference/generic_methods_handle_override_of_non_generic_with_generic: TypeCheckError
+inference/infer_method_missing_params: TypeCheckError
+inference/infer_types_on_generic_instantiations_infer: TypeCheckError
+inference/mixin_inference_outwards_3: TypeCheckError
+inference/mixin_inference_outwards_4: TypeCheckError
+inference/mixin_inference_unification_1: TypeCheckError
+inference/mixin_inference_unification_2: TypeCheckError
+inference_new/infer_assign_to_index_super_upwards: TypeCheckError
+inference_new/infer_assign_to_index_this_upwards: TypeCheckError
+inference_new/infer_assign_to_index_upwards: TypeCheckError
+late_lowering/covariant_late_field: TypeCheckError
+nnbd/covariant_late_field: TypeCheckError
+nnbd/getter_vs_setter_type: TypeCheckError
+nnbd/issue42603: TypeCheckError
+nnbd_mixed/bad_mixins: TypeCheckError
+nnbd_mixed/covariant_from_opt_in: TypeCheckError
+nnbd_mixed/hierarchy/conflict: TypeCheckError
+nnbd_mixed/hierarchy/duplicates: TypeCheckError
+nnbd_mixed/hierarchy/forwarding_semi_stub_field: TypeCheckError
+nnbd_mixed/hierarchy/forwarding_semi_stub_method: TypeCheckError
+nnbd_mixed/hierarchy/forwarding_semi_stub_setter: TypeCheckError
+nnbd_mixed/hierarchy/getter_setter: TypeCheckError
+nnbd_mixed/hierarchy/mix_in_override: TypeCheckError
+nnbd_mixed/hierarchy/override: TypeCheckError
+nnbd_mixed/inheritance_from_opt_in: TypeCheckError
+nnbd_mixed/issue41567: TypeCheckError
+nnbd_mixed/messages_with_types_opt_in: TypeCheckError
+nnbd_mixed/messages_with_types_opt_out: TypeCheckError
+rasta/mixin_library: TypeCheckError
+rasta/super: TypeCheckError
+rasta/super_mixin: TypeCheckError
+rasta/super_operator: TypeCheckError
+rasta/unresolved_recovery: TypeCheckError
+regress/issue_31180: TypeCheckError
+runtime_checks_new/mixin_forwarding_stub_getter: TypeCheckError
diff --git a/pkg/front_end/testcases/named_arguments_anywhere/all_kinds.dart.weak.modular.expect b/pkg/front_end/testcases/named_arguments_anywhere/all_kinds.dart.weak.modular.expect
new file mode 100644
index 0000000..2f58211
--- /dev/null
+++ b/pkg/front_end/testcases/named_arguments_anywhere/all_kinds.dart.weak.modular.expect
@@ -0,0 +1,78 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef B = self::A;
+class A extends core::Object {
+  constructor •(core::int x, core::int y, {required core::int z = #C1}) → self::A
+    : super core::Object::•()
+    ;
+  static factory foo(core::int x, core::int y, {required core::int z = #C1}) → self::A
+    return new self::A::•(x, y, z: z);
+  get property() → (core::int, core::int, {required z: core::int}) → void
+    return throw 42;
+  method bar(core::int x, core::int y, {required core::int z = #C1}) → void {}
+}
+class Test extends self::A {
+  constructor •() → self::Test
+    : super self::A::•(1, 2, z: 3)
+    ;
+  method test() → dynamic {
+    super.{self::A::bar}(1, 2, z: 3);
+    let final core::int #t1 = 1 in let final core::int #t2 = 2 in super.{self::A::bar}(#t1, 3, z: #t2);
+    let final core::int #t3 = 1 in super.{self::A::bar}(2, 3, z: #t3);
+  }
+}
+extension E on self::A {
+  method method1 = self::E|method1;
+  tearoff method1 = self::E|get#method1;
+  method method2 = self::E|method2;
+  tearoff method2 = self::E|get#method2;
+}
+static method foo(core::int x, core::int y, {required core::int z = #C1}) → dynamic {}
+static method E|method1(lowered final self::A #this) → dynamic {
+  let final self::A #t4 = #this in let final core::int #t5 = 1 in self::E|method2(#t4, 2, foo: #t5);
+}
+static method E|get#method1(lowered final self::A #this) → () → dynamic
+  return () → dynamic => self::E|method1(#this);
+static method E|method2(lowered final self::A #this, core::int bar, {core::int? foo = #C1}) → dynamic {}
+static method E|get#method2(lowered final self::A #this) → (core::int, {foo: core::int?}) → dynamic
+  return (core::int bar, {core::int? foo = #C1}) → dynamic => self::E|method2(#this, bar, foo: foo);
+static method test(dynamic d, core::Function f, self::A a) → dynamic {
+  function local(core::int x, core::int y, {required core::int z = #C1}) → void {}
+  self::foo(1, 2, z: 3);
+  let final core::int #t6 = 1 in let final core::int #t7 = 2 in self::foo(#t6, 3, z: #t7);
+  let final core::int #t8 = 1 in self::foo(2, 3, z: #t8);
+  self::A::foo(1, 2, z: 3);
+  let final core::int #t9 = 1 in let final core::int #t10 = 2 in self::A::foo(#t9, 3, z: #t10);
+  let final core::int #t11 = 1 in self::A::foo(2, 3, z: #t11);
+  self::A::foo(1, 2, z: 3);
+  let final core::int #t12 = 1 in let final core::int #t13 = 2 in self::A::foo(#t12, 3, z: #t13);
+  let final core::int #t14 = 1 in self::A::foo(2, 3, z: #t14);
+  new self::A::•(1, 2, z: 3);
+  let final core::int #t15 = 1 in let final core::int #t16 = 2 in new self::A::•(#t15, 3, z: #t16);
+  let final core::int #t17 = 1 in new self::A::•(2, 3, z: #t17);
+  new self::A::•(1, 2, z: 3);
+  let final core::int #t18 = 1 in let final core::int #t19 = 2 in new self::A::•(#t18, 3, z: #t19);
+  let final core::int #t20 = 1 in new self::A::•(2, 3, z: #t20);
+  d{dynamic}.call(1, 2, z: 3);
+  let final core::int #t21 = 1 in let final core::int #t22 = 2 in d{dynamic}.call(#t21, 3, z: #t22);
+  let final core::int #t23 = 1 in d{dynamic}.call(2, 3, z: #t23);
+  f(1, 2, z: 3);
+  let final core::int #t24 = 1 in let final core::int #t25 = 2 in f(#t24, 3, z: #t25);
+  let final core::int #t26 = 1 in f(2, 3, z: #t26);
+  let final self::A #t27 = a in let final core::int #t28 = 1 in let final core::int #t29 = 2 in let final core::int #t30 = 3 in #t27.{self::A::property}{(core::int, core::int, {required z: core::int}) → void}(#t28, #t29, z: #t30){(core::int, core::int, {required z: core::int}) → void};
+  let final self::A #t31 = a in let final core::int #t32 = 1 in let final core::int #t33 = 2 in let final core::int #t34 = 3 in #t31.{self::A::property}{(core::int, core::int, {required z: core::int}) → void}(#t32, #t34, z: #t33){(core::int, core::int, {required z: core::int}) → void};
+  let final self::A #t35 = a in let final core::int #t36 = 1 in let final core::int #t37 = 2 in let final core::int #t38 = 3 in #t35.{self::A::property}{(core::int, core::int, {required z: core::int}) → void}(#t37, #t38, z: #t36){(core::int, core::int, {required z: core::int}) → void};
+  a.{self::A::bar}(1, 2, z: 3){(core::int, core::int, {required z: core::int}) → void};
+  let final self::A #t39 = a in let final core::int #t40 = 1 in let final core::int #t41 = 2 in #t39.{self::A::bar}(#t40, 3, z: #t41){(core::int, core::int, {required z: core::int}) → void};
+  let final self::A #t42 = a in let final core::int #t43 = 1 in #t42.{self::A::bar}(2, 3, z: #t43){(core::int, core::int, {required z: core::int}) → void};
+  local(1, 2, z: 3){(core::int, core::int, {required z: core::int}) → void};
+  let final core::int #t44 = 1 in let final core::int #t45 = 2 in local(#t44, 3, z: #t45){(core::int, core::int, {required z: core::int}) → void};
+  let final core::int #t46 = 1 in local(2, 3, z: #t46){(core::int, core::int, {required z: core::int}) → void};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/named_arguments_anywhere/redirecting_constructor_initializers.dart.weak.modular.expect b/pkg/front_end/testcases/named_arguments_anywhere/redirecting_constructor_initializers.dart.weak.modular.expect
new file mode 100644
index 0000000..5b2dee8
--- /dev/null
+++ b/pkg/front_end/testcases/named_arguments_anywhere/redirecting_constructor_initializers.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor •(core::int x, core::bool y, {required core::String z = #C2}) → self::A
+    : super core::Object::•()
+    ;
+  constructor foo() → self::A
+    : final core::int #t1 = 42, final core::String #t2 = "foo", this self::A::•(#t1, false, z: #t2)
+    ;
+  static factory bar(core::int x, core::bool y, {required core::String z = #C2}) → self::A
+    return new self::A::•(x, y, z: z);
+}
+class B extends self::A {
+  constructor •() → self::B
+    : final core::int #t3 = 42, final core::String #t4 = "foo", super self::A::•(#t3, false, z: #t4)
+    ;
+}
+static method test() → dynamic {
+  new self::A::•(42, false, z: "bar");
+  let final core::int #t5 = 42 in let final core::String #t6 = "bar" in new self::A::•(#t5, false, z: #t6);
+  let final core::String #t7 = "bar" in new self::A::•(42, false, z: #t7);
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::A::bar
+  #C2 = null
+}
diff --git a/pkg/front_end/testcases/new_const_insertion/simple.dart.weak.modular.expect b/pkg/front_end/testcases/new_const_insertion/simple.dart.weak.modular.expect
new file mode 100644
index 0000000..47eae93
--- /dev/null
+++ b/pkg/front_end/testcases/new_const_insertion/simple.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  final field core::int* x;
+  const constructor •(core::int* x) → self::A*
+    : self::A::x = x, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::int* foo = 42;
+  new self::A::•(5);
+  new self::A::•(5.{core::num::+}(5){(core::num*) →* core::int*});
+  new self::A::•(foo);
+  new self::A::•(5.{core::num::+}(foo){(core::num*) →* core::int*});
+}
diff --git a/pkg/front_end/testcases/nnbd/abstract_field_errors.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/abstract_field_errors.dart.weak.modular.expect
new file mode 100644
index 0000000..ce1c9c6
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/abstract_field_errors.dart.weak.modular.expect
@@ -0,0 +1,248 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:5:1: Error: Can't have modifier 'abstract' here.
+// Try removing 'abstract'.
+// abstract int topLevelField;
+// ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:7:1: Error: Can't have modifier 'abstract' here.
+// Try removing 'abstract'.
+// abstract final int finalTopLevelField = 0;
+// ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:9:1: Error: Can't have modifier 'abstract' here.
+// Try removing 'abstract'.
+// abstract const int constField = 0;
+// ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:20:3: Error: Static fields can't be declared 'abstract'.
+// Try removing the 'abstract' or 'static' keyword.
+//   abstract static int staticField;
+//   ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:22:3: Error: Static fields can't be declared 'abstract'.
+// Try removing the 'abstract' or 'static' keyword.
+//   abstract static final int finalStaticField;
+//   ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:24:3: Error: Abstract fields cannot be late.
+// Try removing the 'abstract' or 'late' keyword.
+//   abstract late int lateInstanceField;
+//   ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:26:12: Error: Fields can't be declared both 'abstract' and 'external'.
+// Try removing the 'abstract' or 'external' keyword.
+//   external abstract int externalInstanceField1;
+//            ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:28:12: Error: Fields can't be declared both 'abstract' and 'external'.
+// Try removing the 'abstract' or 'external' keyword.
+//   external abstract final int externalFinalInstanceField1;
+//            ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:30:12: Error: Fields can't be declared both 'abstract' and 'external'.
+// Try removing the 'abstract' or 'external' keyword.
+//   external abstract covariant num externalCovariantInstanceField1;
+//            ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:32:3: Error: Fields can't be declared both 'abstract' and 'external'.
+// Try removing the 'abstract' or 'external' keyword.
+//   abstract external int externalInstanceField2;
+//   ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:34:3: Error: Fields can't be declared both 'abstract' and 'external'.
+// Try removing the 'abstract' or 'external' keyword.
+//   abstract external final int externalFinalInstanceField2;
+//   ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:36:3: Error: Fields can't be declared both 'abstract' and 'external'.
+// Try removing the 'abstract' or 'external' keyword.
+//   abstract external covariant num externalCovariantInstanceField2;
+//   ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:38:12: Error: Fields can't be declared both 'abstract' and 'external'.
+// Try removing the 'abstract' or 'external' keyword.
+//   external abstract late int externalLateInstanceField;
+//            ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:38:12: Error: Abstract fields cannot be late.
+// Try removing the 'abstract' or 'late' keyword.
+//   external abstract late int externalLateInstanceField;
+//            ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:42:3: Error: Static fields can't be declared 'abstract'.
+// Try removing the 'abstract' or 'static' keyword.
+//   abstract static int staticField;
+//   ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:44:3: Error: Static fields can't be declared 'abstract'.
+// Try removing the 'abstract' or 'static' keyword.
+//   abstract static final int finalStaticField;
+//   ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:46:12: Error: Fields can't be declared both 'abstract' and 'external'.
+// Try removing the 'abstract' or 'external' keyword.
+//   external abstract int externalInstanceField;
+//            ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:48:12: Error: Fields can't be declared both 'abstract' and 'external'.
+// Try removing the 'abstract' or 'external' keyword.
+//   external abstract final int externalFinalInstanceField;
+//            ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:50:12: Error: Fields can't be declared both 'abstract' and 'external'.
+// Try removing the 'abstract' or 'external' keyword.
+//   external abstract covariant num externalCovariantInstanceField;
+//            ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:55:16: Error: Extension fields can't be declared 'abstract'.
+// Try removing the 'abstract' keyword.
+//   abstract int extensionInstanceField;
+//                ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:55:16: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   abstract int extensionInstanceField;
+//                ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:56:22: Error: Extension fields can't be declared 'abstract'.
+// Try removing the 'abstract' keyword.
+//   abstract final int finalExtensionInstanceField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:56:22: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   abstract final int finalExtensionInstanceField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:57:23: Error: Extension fields can't be declared 'abstract'.
+// Try removing the 'abstract' keyword.
+//   abstract static int extensionStaticField = 0;
+//                       ^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:57:3: Error: Static fields can't be declared 'abstract'.
+// Try removing the 'abstract' or 'static' keyword.
+//   abstract static int extensionStaticField = 0;
+//   ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:58:29: Error: Extension fields can't be declared 'abstract'.
+// Try removing the 'abstract' keyword.
+//   abstract static final int finalExtensionStaticField = 0;
+//                             ^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:58:3: Error: Static fields can't be declared 'abstract'.
+// Try removing the 'abstract' or 'static' keyword.
+//   abstract static final int finalExtensionStaticField = 0;
+//   ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:5:14: Error: Field 'topLevelField' should be initialized because its type 'int' doesn't allow null.
+// abstract int topLevelField;
+//              ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:20:23: Error: Field 'staticField' should be initialized because its type 'int' doesn't allow null.
+//   abstract static int staticField;
+//                       ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:22:29: Error: Field 'finalStaticField' should be initialized because its type 'int' doesn't allow null.
+//   abstract static final int finalStaticField;
+//                             ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:42:23: Error: Field 'staticField' should be initialized because its type 'int' doesn't allow null.
+//   abstract static int staticField;
+//                       ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:44:29: Error: Field 'finalStaticField' should be initialized because its type 'int' doesn't allow null.
+//   abstract static final int finalStaticField;
+//                             ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:12:37: Error: Abstract fields cannot have initializers.
+// Try removing the initializer or the 'abstract' keyword.
+//   abstract int fieldWithInitializer = 0;
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:18:10: Error: Abstract fields cannot have initializers.
+// Try removing the field initializer or the 'abstract' keyword from the field declaration.
+//   A(this.initializedField1) : this.initializedField2 = 0;
+//          ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:18:36: Error: Abstract fields cannot have initializers.
+// Try removing the field initializer or the 'abstract' keyword from the field declaration.
+//   A(this.initializedField1) : this.initializedField2 = 0;
+//                                    ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:22:29: Error: Final field 'finalStaticField' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   abstract static final int finalStaticField;
+//                             ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/abstract_field_errors.dart:44:29: Error: Final field 'finalStaticField' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   abstract static final int finalStaticField;
+//                             ^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  static field core::int staticField = null;
+  static final field core::int finalStaticField = null;
+  late field core::int lateInstanceField;
+  constructor •(core::int initializedField1) → self::A
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/nnbd/abstract_field_errors.dart:18:10: Error: Abstract fields cannot have initializers.
+Try removing the field initializer or the 'abstract' keyword from the field declaration.
+  A(this.initializedField1) : this.initializedField2 = 0;
+         ^^^^^^^^^^^^^^^^^", final dynamic #t2 = invalid-expression "pkg/front_end/testcases/nnbd/abstract_field_errors.dart:18:36: Error: Abstract fields cannot have initializers.
+Try removing the field initializer or the 'abstract' keyword from the field declaration.
+  A(this.initializedField1) : this.initializedField2 = 0;
+                                   ^^^^^^^^^^^^^^^^^"
+    ;
+  abstract get fieldWithInitializer() → core::int;
+  abstract set fieldWithInitializer(core::int #externalFieldValue) → void;
+  abstract get initializedField1() → core::int;
+  abstract set initializedField1(core::int #externalFieldValue) → void;
+  abstract get initializedField2() → core::int;
+  abstract set initializedField2(core::int #externalFieldValue) → void;
+  external get externalInstanceField1() → core::int;
+  external set externalInstanceField1(core::int #externalFieldValue) → void;
+  external get externalFinalInstanceField1() → core::int;
+  external get externalCovariantInstanceField1() → core::num;
+  external set externalCovariantInstanceField1(covariant-by-declaration core::num #externalFieldValue) → void;
+  external get externalInstanceField2() → core::int;
+  external set externalInstanceField2(core::int #externalFieldValue) → void;
+  external get externalFinalInstanceField2() → core::int;
+  external get externalCovariantInstanceField2() → core::num;
+  external set externalCovariantInstanceField2(covariant-by-declaration core::num #externalFieldValue) → void;
+  external get externalLateInstanceField() → core::int;
+  external set externalLateInstanceField(core::int #externalFieldValue) → void;
+}
+abstract class B extends core::Object /*isMixinDeclaration*/  {
+  static field core::int staticField = null;
+  static final field core::int finalStaticField = null;
+  external get externalInstanceField() → core::int;
+  external set externalInstanceField(core::int #externalFieldValue) → void;
+  external get externalFinalInstanceField() → core::int;
+  external get externalCovariantInstanceField() → core::num;
+  external set externalCovariantInstanceField(covariant-by-declaration core::num #externalFieldValue) → void;
+}
+extension Extension on self::A {
+  get extensionInstanceField = get self::Extension|extensionInstanceField;
+  set extensionInstanceField = set self::Extension|extensionInstanceField;
+  get finalExtensionInstanceField = get self::Extension|finalExtensionInstanceField;
+  static field extensionStaticField = self::Extension|extensionStaticField;
+  static field finalExtensionStaticField = self::Extension|finalExtensionStaticField;
+}
+static field core::int topLevelField;
+static final field core::int finalTopLevelField = 0;
+static const field core::int constField = #C1;
+static field core::int Extension|extensionStaticField = 0;
+static final field core::int Extension|finalExtensionStaticField = 0;
+static abstract get Extension|extensionInstanceField() → core::int;
+static abstract set Extension|extensionInstanceField(core::int #externalFieldValue) → void;
+static abstract get Extension|finalExtensionInstanceField() → core::int;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+}
diff --git a/pkg/front_end/testcases/nnbd/abstract_fields.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/abstract_fields.dart.weak.modular.expect
new file mode 100644
index 0000000..f9cfd21
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/abstract_fields.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  abstract get instanceField() → core::int;
+  abstract set instanceField(core::int #externalFieldValue) → void;
+  abstract get finalInstanceField() → core::int;
+  abstract get covariantInstanceField() → core::num;
+  abstract set covariantInstanceField(covariant-by-declaration core::num #externalFieldValue) → void;
+}
+abstract class B extends core::Object /*isMixinDeclaration*/  {
+  abstract get instanceField() → core::int;
+  abstract set instanceField(core::int #externalFieldValue) → void;
+  abstract get finalInstanceField() → core::int;
+  abstract get covariantInstanceField() → core::num;
+  abstract set covariantInstanceField(covariant-by-declaration core::num #externalFieldValue) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/abstract_fields_spec.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/abstract_fields_spec.dart.weak.modular.expect
new file mode 100644
index 0000000..efa8606
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/abstract_fields_spec.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  abstract get i1() → core::int;
+  abstract set i1(core::int #externalFieldValue) → void;
+  abstract get i2() → core::int;
+  abstract set i2(core::int #externalFieldValue) → void;
+  abstract get x() → dynamic;
+  abstract set x(dynamic #externalFieldValue) → void;
+  abstract get fi() → core::int;
+  abstract get fx() → dynamic;
+  abstract get cn() → core::num;
+  abstract set cn(covariant-by-declaration core::num #externalFieldValue) → void;
+  abstract get cx() → dynamic;
+  abstract set cx(covariant-by-declaration dynamic #externalFieldValue) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.weak.modular.expect
new file mode 100644
index 0000000..02aa3e0
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+
+import "org-dartlang-testcase:///ambiguous_main_export_lib0.dart";
+
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/ambiguous_main_export_lib0.dart:6:1: Error: 'main' is exported from both 'pkg/front_end/testcases/nnbd/ambiguous_main_export_lib1.dart' and 'pkg/front_end/testcases/nnbd/ambiguous_main_export_lib2.dart'.
+// export 'ambiguous_main_export_lib2.dart';
+// ^
+//
+import self as self2;
+import "dart:core" as core;
+
+export "org-dartlang-testcase:///ambiguous_main_export_lib1.dart";
+export "org-dartlang-testcase:///ambiguous_main_export_lib2.dart";
+
+static const field dynamic _exports# = #C1 /*isLegacy*/;
+
+library /*isNonNullableByDefault*/;
+import self as self3;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::print(42);
+}
+
+library /*isNonNullableByDefault*/;
+import self as self4;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::print(87);
+}
+
+constants  {
+  #C1 = "{\"main\":\"'main' is exported from both 'pkg/front_end/testcases/nnbd/ambiguous_main_export_lib1.dart' and 'pkg/front_end/testcases/nnbd/ambiguous_main_export_lib2.dart'.\"}"
+}
diff --git a/pkg/front_end/testcases/nnbd/assign_type_variable.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/assign_type_variable.dart.weak.modular.expect
new file mode 100644
index 0000000..e981e5c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/assign_type_variable.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Class<E extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::E%>
+    : super core::Object::•()
+    ;
+  method method(covariant-by-class self::Class::E% e) → void {
+    e = self::id<self::Class::E%>(e);
+    e = self::id<self::Class::E%>(e);
+    if(!(e == null)) {
+      self::Class::E% e2 = e{self::Class::E% & core::Object /* '%' & '!' = '!' */};
+      e2 = self::id<self::Class::E%>(e{self::Class::E% & core::Object /* '%' & '!' = '!' */});
+      e2 = self::id<self::Class::E%>(e{self::Class::E% & core::Object /* '%' & '!' = '!' */});
+      e2 = self::id<self::Class::E%>(e2);
+      e2 = self::id<self::Class::E%>(e2);
+    }
+  }
+}
+static method id<T extends core::Object? = dynamic>(self::id::T% t) → self::id::T%
+  return t;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/assignability.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/assignability.dart.weak.modular.expect
new file mode 100644
index 0000000..5603cdc
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/assignability.dart.weak.modular.expect
@@ -0,0 +1,1790 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:114:22: Error: A value of type 'Object?' can't be assigned to a variable of type 'Object' because 'Object?' is nullable and 'Object' isn't.
+//  - 'Object' is from 'dart:core'.
+//   Object objectVar = objectNullableArg;
+//                      ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:115:15: Error: A value of type 'num?' can't be assigned to a variable of type 'Object' because 'num?' is nullable and 'Object' isn't.
+//  - 'Object' is from 'dart:core'.
+//   objectVar = numNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:116:15: Error: A value of type 'int?' can't be assigned to a variable of type 'Object' because 'int?' is nullable and 'Object' isn't.
+//  - 'Object' is from 'dart:core'.
+//   objectVar = intNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:117:15: Error: A value of type 'double?' can't be assigned to a variable of type 'Object' because 'double?' is nullable and 'Object' isn't.
+//  - 'Object' is from 'dart:core'.
+//   objectVar = doubleNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:118:15: Error: A value of type 'Function?' can't be assigned to a variable of type 'Object' because 'Function?' is nullable and 'Object' isn't.
+//  - 'Function' is from 'dart:core'.
+//  - 'Object' is from 'dart:core'.
+//   objectVar = functionNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:119:15: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'Object' because 'void Function()?' is nullable and 'Object' isn't.
+//  - 'Object' is from 'dart:core'.
+//   objectVar = toVoidNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:120:15: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'Object' because 'Tearoffable?' is nullable and 'Object' isn't.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//  - 'Object' is from 'dart:core'.
+//   objectVar = tearoffableNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:121:15: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'Object' because 'XnonNull?' is nullable and 'Object' isn't.
+//  - 'Object' is from 'dart:core'.
+//   objectVar = xNonNullNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:122:15: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'Object' because 'XpotentiallyNull' is nullable and 'Object' isn't.
+//  - 'Object' is from 'dart:core'.
+//   objectVar = xPotentiallyNullArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:123:15: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'Object' because 'XpotentiallyNull?' is nullable and 'Object' isn't.
+//  - 'Object' is from 'dart:core'.
+//   objectVar = xPotentiallyNullNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:124:15: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'Object' because 'YnonNull?' is nullable and 'Object' isn't.
+//  - 'Object' is from 'dart:core'.
+//   objectVar = yNonNullNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:125:15: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'Object' because 'YpotentiallyNull' is nullable and 'Object' isn't.
+//  - 'Object' is from 'dart:core'.
+//   objectVar = yPotentiallyNullArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:126:15: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'Object' because 'YpotentiallyNull?' is nullable and 'Object' isn't.
+//  - 'Object' is from 'dart:core'.
+//   objectVar = yPotentiallyNullNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:128:16: Error: A value of type 'Object' can't be assigned to a variable of type 'num'.
+//  - 'Object' is from 'dart:core'.
+//   num numVar = objectArg;
+//                ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:129:12: Error: A value of type 'Object?' can't be assigned to a variable of type 'num'.
+//  - 'Object' is from 'dart:core'.
+//   numVar = objectNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:130:12: Error: A value of type 'num?' can't be assigned to a variable of type 'num' because 'num?' is nullable and 'num' isn't.
+//   numVar = numNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:131:12: Error: A value of type 'int?' can't be assigned to a variable of type 'num' because 'int?' is nullable and 'num' isn't.
+//   numVar = intNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:132:12: Error: A value of type 'double?' can't be assigned to a variable of type 'num' because 'double?' is nullable and 'num' isn't.
+//   numVar = doubleNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:133:12: Error: A value of type 'Function' can't be assigned to a variable of type 'num'.
+//  - 'Function' is from 'dart:core'.
+//   numVar = functionArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:134:12: Error: A value of type 'Function?' can't be assigned to a variable of type 'num'.
+//  - 'Function' is from 'dart:core'.
+//   numVar = functionNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:135:12: Error: A value of type 'void Function()' can't be assigned to a variable of type 'num'.
+//   numVar = toVoidArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:136:12: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'num'.
+//   numVar = toVoidNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:137:12: Error: A value of type 'Tearoffable' can't be assigned to a variable of type 'num'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   numVar = tearoffableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:138:12: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'num'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   numVar = tearoffableNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:139:12: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'num'.
+//   numVar = xNonNullArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:140:12: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'num'.
+//   numVar = xNonNullNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:141:12: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'num'.
+//   numVar = xPotentiallyNullArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:142:12: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'num'.
+//   numVar = xPotentiallyNullNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:143:12: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'num'.
+//   numVar = yNonNullArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:144:12: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'num'.
+//   numVar = yNonNullNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:145:12: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'num'.
+//   numVar = yPotentiallyNullArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:146:12: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'num'.
+//   numVar = yPotentiallyNullNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:148:16: Error: A value of type 'Object' can't be assigned to a variable of type 'int'.
+//  - 'Object' is from 'dart:core'.
+//   int intVar = objectArg;
+//                ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:149:12: Error: A value of type 'Object?' can't be assigned to a variable of type 'int'.
+//  - 'Object' is from 'dart:core'.
+//   intVar = objectNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:150:12: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+//   intVar = numArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:151:12: Error: A value of type 'num?' can't be assigned to a variable of type 'int'.
+//   intVar = numNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:152:12: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+//   intVar = intNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:153:12: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//   intVar = doubleArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:154:12: Error: A value of type 'double?' can't be assigned to a variable of type 'int'.
+//   intVar = doubleNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:155:12: Error: A value of type 'Function' can't be assigned to a variable of type 'int'.
+//  - 'Function' is from 'dart:core'.
+//   intVar = functionArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:156:12: Error: A value of type 'Function?' can't be assigned to a variable of type 'int'.
+//  - 'Function' is from 'dart:core'.
+//   intVar = functionNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:157:12: Error: A value of type 'void Function()' can't be assigned to a variable of type 'int'.
+//   intVar = toVoidArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:158:12: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'int'.
+//   intVar = toVoidNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:159:12: Error: A value of type 'Tearoffable' can't be assigned to a variable of type 'int'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   intVar = tearoffableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:160:12: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'int'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   intVar = tearoffableNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:161:12: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'int'.
+//   intVar = xNonNullArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:162:12: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'int'.
+//   intVar = xNonNullNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:163:12: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'int'.
+//   intVar = xPotentiallyNullArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:164:12: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'int'.
+//   intVar = xPotentiallyNullNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:165:12: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'int'.
+//   intVar = yNonNullArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:166:12: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'int'.
+//   intVar = yNonNullNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:167:12: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'int'.
+//   intVar = yPotentiallyNullArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:168:12: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'int'.
+//   intVar = yPotentiallyNullNullableArg;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:170:22: Error: A value of type 'Object' can't be assigned to a variable of type 'double'.
+//  - 'Object' is from 'dart:core'.
+//   double doubleVar = objectArg;
+//                      ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:171:15: Error: A value of type 'Object?' can't be assigned to a variable of type 'double'.
+//  - 'Object' is from 'dart:core'.
+//   doubleVar = objectNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:172:15: Error: A value of type 'num' can't be assigned to a variable of type 'double'.
+//   doubleVar = numArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:173:15: Error: A value of type 'num?' can't be assigned to a variable of type 'double'.
+//   doubleVar = numNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:174:15: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+//   doubleVar = intArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:175:15: Error: A value of type 'int?' can't be assigned to a variable of type 'double'.
+//   doubleVar = intNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:176:15: Error: A value of type 'double?' can't be assigned to a variable of type 'double' because 'double?' is nullable and 'double' isn't.
+//   doubleVar = doubleNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:177:15: Error: A value of type 'Function' can't be assigned to a variable of type 'double'.
+//  - 'Function' is from 'dart:core'.
+//   doubleVar = functionArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:178:15: Error: A value of type 'Function?' can't be assigned to a variable of type 'double'.
+//  - 'Function' is from 'dart:core'.
+//   doubleVar = functionNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:179:15: Error: A value of type 'void Function()' can't be assigned to a variable of type 'double'.
+//   doubleVar = toVoidArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:180:15: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'double'.
+//   doubleVar = toVoidNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:181:15: Error: A value of type 'Tearoffable' can't be assigned to a variable of type 'double'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   doubleVar = tearoffableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:182:15: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'double'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   doubleVar = tearoffableNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:183:15: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'double'.
+//   doubleVar = xNonNullArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:184:15: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'double'.
+//   doubleVar = xNonNullNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:185:15: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'double'.
+//   doubleVar = xPotentiallyNullArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:186:15: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'double'.
+//   doubleVar = xPotentiallyNullNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:187:15: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'double'.
+//   doubleVar = yNonNullArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:188:15: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'double'.
+//   doubleVar = yNonNullNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:189:15: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'double'.
+//   doubleVar = yPotentiallyNullArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:190:15: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'double'.
+//   doubleVar = yPotentiallyNullNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:192:26: Error: A value of type 'Object' can't be assigned to a variable of type 'Function'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Function' is from 'dart:core'.
+//   Function functionVar = objectArg;
+//                          ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:193:17: Error: A value of type 'Object?' can't be assigned to a variable of type 'Function'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = objectNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:194:17: Error: A value of type 'num' can't be assigned to a variable of type 'Function'.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = numArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:195:17: Error: A value of type 'num?' can't be assigned to a variable of type 'Function'.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = numNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:196:17: Error: A value of type 'int' can't be assigned to a variable of type 'Function'.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = intArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:197:17: Error: A value of type 'int?' can't be assigned to a variable of type 'Function'.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = intNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:198:17: Error: A value of type 'double' can't be assigned to a variable of type 'Function'.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = doubleArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:199:17: Error: A value of type 'double?' can't be assigned to a variable of type 'Function'.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = doubleNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:200:17: Error: A value of type 'Function?' can't be assigned to a variable of type 'Function' because 'Function?' is nullable and 'Function' isn't.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = functionNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:201:17: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'Function' because 'void Function()?' is nullable and 'Function' isn't.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = toVoidNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:202:17: Error: Can't tear off method 'call' from a potentially null value.
+//   functionVar = tearoffableNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:203:17: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'Function'.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = xNonNullArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:204:17: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'Function'.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = xNonNullNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:205:17: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'Function'.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = xPotentiallyNullArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:206:17: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'Function'.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = xPotentiallyNullNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:207:17: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'Function'.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = yNonNullArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:208:17: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'Function'.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = yNonNullNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:209:17: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'Function'.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = yPotentiallyNullArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:210:17: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'Function'.
+//  - 'Function' is from 'dart:core'.
+//   functionVar = yPotentiallyNullNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:212:31: Error: A value of type 'Object' can't be assigned to a variable of type 'void Function()'.
+//  - 'Object' is from 'dart:core'.
+//   void Function() toVoidVar = objectArg;
+//                               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:213:15: Error: A value of type 'Object?' can't be assigned to a variable of type 'void Function()'.
+//  - 'Object' is from 'dart:core'.
+//   toVoidVar = objectNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:214:15: Error: A value of type 'num' can't be assigned to a variable of type 'void Function()'.
+//   toVoidVar = numArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:215:15: Error: A value of type 'num?' can't be assigned to a variable of type 'void Function()'.
+//   toVoidVar = numNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:216:15: Error: A value of type 'int' can't be assigned to a variable of type 'void Function()'.
+//   toVoidVar = intArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:217:15: Error: A value of type 'int?' can't be assigned to a variable of type 'void Function()'.
+//   toVoidVar = intNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:218:15: Error: A value of type 'double' can't be assigned to a variable of type 'void Function()'.
+//   toVoidVar = doubleArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:219:15: Error: A value of type 'double?' can't be assigned to a variable of type 'void Function()'.
+//   toVoidVar = doubleNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:220:15: Error: A value of type 'Function' can't be assigned to a variable of type 'void Function()'.
+//  - 'Function' is from 'dart:core'.
+//   toVoidVar = functionArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:221:15: Error: A value of type 'Function?' can't be assigned to a variable of type 'void Function()'.
+//  - 'Function' is from 'dart:core'.
+//   toVoidVar = functionNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:222:15: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'void Function()' because 'void Function()?' is nullable and 'void Function()' isn't.
+//   toVoidVar = toVoidNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:223:15: Error: Can't tear off method 'call' from a potentially null value.
+//   toVoidVar = tearoffableNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:224:15: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'void Function()'.
+//   toVoidVar = xNonNullArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:225:15: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'void Function()'.
+//   toVoidVar = xNonNullNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:226:15: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'void Function()'.
+//   toVoidVar = xPotentiallyNullArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:227:15: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'void Function()'.
+//   toVoidVar = xPotentiallyNullNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:228:15: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'void Function()'.
+//   toVoidVar = yNonNullArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:229:15: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'void Function()'.
+//   toVoidVar = yNonNullNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:230:15: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'void Function()'.
+//   toVoidVar = yPotentiallyNullArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:231:15: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'void Function()'.
+//   toVoidVar = yPotentiallyNullNullableArg;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:233:32: Error: A value of type 'Object' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   Tearoffable tearoffableVar = objectArg;
+//                                ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:234:20: Error: A value of type 'Object?' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = objectNullableArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:235:20: Error: A value of type 'num' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = numArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:236:20: Error: A value of type 'num?' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = numNullableArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:237:20: Error: A value of type 'int' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = intArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:238:20: Error: A value of type 'int?' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = intNullableArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:239:20: Error: A value of type 'double' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = doubleArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:240:20: Error: A value of type 'double?' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = doubleNullableArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:241:20: Error: A value of type 'Function' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Function' is from 'dart:core'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = functionArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:242:20: Error: A value of type 'Function?' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Function' is from 'dart:core'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = functionNullableArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:243:20: Error: A value of type 'void Function()' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = toVoidArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:244:20: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = toVoidNullableArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:245:20: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'Tearoffable' because 'Tearoffable?' is nullable and 'Tearoffable' isn't.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = tearoffableNullableArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:246:20: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = xNonNullArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:247:20: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = xNonNullNullableArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:248:20: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = xPotentiallyNullArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:249:20: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = xPotentiallyNullNullableArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:250:20: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = yNonNullArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:251:20: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = yNonNullNullableArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:252:20: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = yPotentiallyNullArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:253:20: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'Tearoffable'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   tearoffableVar = yPotentiallyNullNullableArg;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:255:26: Error: A value of type 'Object' can't be assigned to a variable of type 'XnonNull'.
+//  - 'Object' is from 'dart:core'.
+//   XnonNull xNonNullVar = objectArg;
+//                          ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:256:17: Error: A value of type 'Object?' can't be assigned to a variable of type 'XnonNull'.
+//  - 'Object' is from 'dart:core'.
+//   xNonNullVar = objectNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:257:17: Error: A value of type 'num' can't be assigned to a variable of type 'XnonNull'.
+//   xNonNullVar = numArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:258:17: Error: A value of type 'num?' can't be assigned to a variable of type 'XnonNull'.
+//   xNonNullVar = numNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:259:17: Error: A value of type 'int' can't be assigned to a variable of type 'XnonNull'.
+//   xNonNullVar = intArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:260:17: Error: A value of type 'int?' can't be assigned to a variable of type 'XnonNull'.
+//   xNonNullVar = intNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:261:17: Error: A value of type 'double' can't be assigned to a variable of type 'XnonNull'.
+//   xNonNullVar = doubleArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:262:17: Error: A value of type 'double?' can't be assigned to a variable of type 'XnonNull'.
+//   xNonNullVar = doubleNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:263:17: Error: A value of type 'Function' can't be assigned to a variable of type 'XnonNull'.
+//  - 'Function' is from 'dart:core'.
+//   xNonNullVar = functionArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:264:17: Error: A value of type 'Function?' can't be assigned to a variable of type 'XnonNull'.
+//  - 'Function' is from 'dart:core'.
+//   xNonNullVar = functionNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:265:17: Error: A value of type 'void Function()' can't be assigned to a variable of type 'XnonNull'.
+//   xNonNullVar = toVoidArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:266:17: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'XnonNull'.
+//   xNonNullVar = toVoidNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:267:17: Error: A value of type 'Tearoffable' can't be assigned to a variable of type 'XnonNull'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   xNonNullVar = tearoffableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:268:17: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'XnonNull'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   xNonNullVar = tearoffableNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:269:17: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'XnonNull' because 'XnonNull?' is nullable and 'XnonNull' isn't.
+//   xNonNullVar = xNonNullNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:270:17: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'XnonNull'.
+//   xNonNullVar = xPotentiallyNullArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:271:17: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'XnonNull'.
+//   xNonNullVar = xPotentiallyNullNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:272:17: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'XnonNull' because 'YnonNull?' is nullable and 'XnonNull' isn't.
+//   xNonNullVar = yNonNullNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:273:17: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'XnonNull'.
+//   xNonNullVar = yPotentiallyNullArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:274:17: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'XnonNull'.
+//   xNonNullVar = yPotentiallyNullNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:276:42: Error: A value of type 'Object' can't be assigned to a variable of type 'XpotentiallyNull'.
+//  - 'Object' is from 'dart:core'.
+//   XpotentiallyNull xPotentiallyNullVar = objectArg;
+//                                          ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:277:25: Error: A value of type 'Object?' can't be assigned to a variable of type 'XpotentiallyNull'.
+//  - 'Object' is from 'dart:core'.
+//   xPotentiallyNullVar = objectNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:278:25: Error: A value of type 'num' can't be assigned to a variable of type 'XpotentiallyNull'.
+//   xPotentiallyNullVar = numArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:279:25: Error: A value of type 'num?' can't be assigned to a variable of type 'XpotentiallyNull'.
+//   xPotentiallyNullVar = numNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:280:25: Error: A value of type 'int' can't be assigned to a variable of type 'XpotentiallyNull'.
+//   xPotentiallyNullVar = intArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:281:25: Error: A value of type 'int?' can't be assigned to a variable of type 'XpotentiallyNull'.
+//   xPotentiallyNullVar = intNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:282:25: Error: A value of type 'double' can't be assigned to a variable of type 'XpotentiallyNull'.
+//   xPotentiallyNullVar = doubleArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:283:25: Error: A value of type 'double?' can't be assigned to a variable of type 'XpotentiallyNull'.
+//   xPotentiallyNullVar = doubleNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:284:25: Error: A value of type 'Function' can't be assigned to a variable of type 'XpotentiallyNull'.
+//  - 'Function' is from 'dart:core'.
+//   xPotentiallyNullVar = functionArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:285:25: Error: A value of type 'Function?' can't be assigned to a variable of type 'XpotentiallyNull'.
+//  - 'Function' is from 'dart:core'.
+//   xPotentiallyNullVar = functionNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:286:25: Error: A value of type 'void Function()' can't be assigned to a variable of type 'XpotentiallyNull'.
+//   xPotentiallyNullVar = toVoidArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:287:25: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'XpotentiallyNull'.
+//   xPotentiallyNullVar = toVoidNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:288:25: Error: A value of type 'Tearoffable' can't be assigned to a variable of type 'XpotentiallyNull'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   xPotentiallyNullVar = tearoffableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:289:25: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'XpotentiallyNull'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   xPotentiallyNullVar = tearoffableNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:290:25: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'XpotentiallyNull'.
+//   xPotentiallyNullVar = xNonNullArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:291:25: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'XpotentiallyNull'.
+//   xPotentiallyNullVar = xNonNullNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:292:25: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'XpotentiallyNull' because 'XpotentiallyNull?' is nullable and 'XpotentiallyNull' isn't.
+//   xPotentiallyNullVar = xPotentiallyNullNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:293:25: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'XpotentiallyNull'.
+//   xPotentiallyNullVar = yNonNullArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:294:25: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'XpotentiallyNull'.
+//   xPotentiallyNullVar = yNonNullNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:295:25: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'XpotentiallyNull' because 'YpotentiallyNull?' is nullable and 'XpotentiallyNull' isn't.
+//   xPotentiallyNullVar = yPotentiallyNullNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:297:26: Error: A value of type 'Object' can't be assigned to a variable of type 'YnonNull'.
+//  - 'Object' is from 'dart:core'.
+//   YnonNull yNonNullVar = objectArg;
+//                          ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:298:17: Error: A value of type 'Object?' can't be assigned to a variable of type 'YnonNull'.
+//  - 'Object' is from 'dart:core'.
+//   yNonNullVar = objectNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:299:17: Error: A value of type 'num' can't be assigned to a variable of type 'YnonNull'.
+//   yNonNullVar = numArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:300:17: Error: A value of type 'num?' can't be assigned to a variable of type 'YnonNull'.
+//   yNonNullVar = numNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:301:17: Error: A value of type 'int' can't be assigned to a variable of type 'YnonNull'.
+//   yNonNullVar = intArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:302:17: Error: A value of type 'int?' can't be assigned to a variable of type 'YnonNull'.
+//   yNonNullVar = intNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:303:17: Error: A value of type 'double' can't be assigned to a variable of type 'YnonNull'.
+//   yNonNullVar = doubleArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:304:17: Error: A value of type 'double?' can't be assigned to a variable of type 'YnonNull'.
+//   yNonNullVar = doubleNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:305:17: Error: A value of type 'Function' can't be assigned to a variable of type 'YnonNull'.
+//  - 'Function' is from 'dart:core'.
+//   yNonNullVar = functionArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:306:17: Error: A value of type 'Function?' can't be assigned to a variable of type 'YnonNull'.
+//  - 'Function' is from 'dart:core'.
+//   yNonNullVar = functionNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:307:17: Error: A value of type 'void Function()' can't be assigned to a variable of type 'YnonNull'.
+//   yNonNullVar = toVoidArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:308:17: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'YnonNull'.
+//   yNonNullVar = toVoidNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:309:17: Error: A value of type 'Tearoffable' can't be assigned to a variable of type 'YnonNull'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   yNonNullVar = tearoffableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:310:17: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'YnonNull'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   yNonNullVar = tearoffableNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:311:17: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'YnonNull'.
+//   yNonNullVar = xNonNullArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:312:17: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'YnonNull'.
+//   yNonNullVar = xNonNullNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:313:17: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'YnonNull'.
+//   yNonNullVar = xPotentiallyNullArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:314:17: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'YnonNull'.
+//   yNonNullVar = xPotentiallyNullNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:315:17: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'YnonNull' because 'YnonNull?' is nullable and 'YnonNull' isn't.
+//   yNonNullVar = yNonNullNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:316:17: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'YnonNull'.
+//   yNonNullVar = yPotentiallyNullArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:317:17: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'YnonNull'.
+//   yNonNullVar = yPotentiallyNullNullableArg;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:319:42: Error: A value of type 'Object' can't be assigned to a variable of type 'YpotentiallyNull'.
+//  - 'Object' is from 'dart:core'.
+//   YpotentiallyNull yPotentiallyNullVar = objectArg;
+//                                          ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:320:25: Error: A value of type 'Object?' can't be assigned to a variable of type 'YpotentiallyNull'.
+//  - 'Object' is from 'dart:core'.
+//   yPotentiallyNullVar = objectNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:321:25: Error: A value of type 'num' can't be assigned to a variable of type 'YpotentiallyNull'.
+//   yPotentiallyNullVar = numArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:322:25: Error: A value of type 'num?' can't be assigned to a variable of type 'YpotentiallyNull'.
+//   yPotentiallyNullVar = numNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:323:25: Error: A value of type 'int' can't be assigned to a variable of type 'YpotentiallyNull'.
+//   yPotentiallyNullVar = intArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:324:25: Error: A value of type 'int?' can't be assigned to a variable of type 'YpotentiallyNull'.
+//   yPotentiallyNullVar = intNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:325:25: Error: A value of type 'double' can't be assigned to a variable of type 'YpotentiallyNull'.
+//   yPotentiallyNullVar = doubleArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:326:25: Error: A value of type 'double?' can't be assigned to a variable of type 'YpotentiallyNull'.
+//   yPotentiallyNullVar = doubleNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:327:25: Error: A value of type 'Function' can't be assigned to a variable of type 'YpotentiallyNull'.
+//  - 'Function' is from 'dart:core'.
+//   yPotentiallyNullVar = functionArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:328:25: Error: A value of type 'Function?' can't be assigned to a variable of type 'YpotentiallyNull'.
+//  - 'Function' is from 'dart:core'.
+//   yPotentiallyNullVar = functionNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:329:25: Error: A value of type 'void Function()' can't be assigned to a variable of type 'YpotentiallyNull'.
+//   yPotentiallyNullVar = toVoidArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:330:25: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'YpotentiallyNull'.
+//   yPotentiallyNullVar = toVoidNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:331:25: Error: A value of type 'Tearoffable' can't be assigned to a variable of type 'YpotentiallyNull'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   yPotentiallyNullVar = tearoffableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:332:25: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'YpotentiallyNull'.
+//  - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+//   yPotentiallyNullVar = tearoffableNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:333:25: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'YpotentiallyNull'.
+//   yPotentiallyNullVar = xNonNullArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:334:25: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'YpotentiallyNull'.
+//   yPotentiallyNullVar = xNonNullNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:335:25: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'YpotentiallyNull'.
+//   yPotentiallyNullVar = xPotentiallyNullArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:336:25: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'YpotentiallyNull'.
+//   yPotentiallyNullVar = xPotentiallyNullNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:337:25: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'YpotentiallyNull'.
+//   yPotentiallyNullVar = yNonNullArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:338:25: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'YpotentiallyNull'.
+//   yPotentiallyNullVar = yNonNullNullableArg;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability.dart:339:25: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'YpotentiallyNull' because 'YpotentiallyNull?' is nullable and 'YpotentiallyNull' isn't.
+//   yPotentiallyNullVar = yPotentiallyNullNullableArg;
+//                         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Tearoffable extends core::Object {
+  synthetic constructor •() → self::Tearoffable
+    : super core::Object::•()
+    ;
+  method call() → void {}
+}
+static method ok<XnonNull extends core::Object, YnonNull extends self::ok::XnonNull = core::Object, XpotentiallyNull extends core::Object?, YpotentiallyNull extends self::ok::XpotentiallyNull% = core::Object?>(dynamic dynamicArg, core::Object objectArg, core::num numArg, core::int intArg, core::double doubleArg, core::Function functionArg, () → void toVoidArg, self::Tearoffable tearoffableArg, self::ok::XnonNull xNonNullArg, self::ok::XpotentiallyNull% xPotentiallyNullArg, self::ok::YnonNull yNonNullArg, self::ok::YpotentiallyNull% yPotentiallyNullArg) → dynamic {
+  dynamic dynamicVar = dynamicArg;
+  dynamicVar = objectArg;
+  dynamicVar = numArg;
+  dynamicVar = intArg;
+  dynamicVar = doubleArg;
+  dynamicVar = functionArg;
+  dynamicVar = toVoidArg;
+  dynamicVar = tearoffableArg;
+  dynamicVar = xNonNullArg;
+  dynamicVar = xPotentiallyNullArg;
+  dynamicVar = yNonNullArg;
+  dynamicVar = yPotentiallyNullArg;
+  core::Object objectVar = dynamicArg as{TypeError,ForDynamic,ForNonNullableByDefault} core::Object;
+  objectVar = objectArg;
+  objectVar = numArg;
+  objectVar = intArg;
+  objectVar = functionArg;
+  objectVar = toVoidArg;
+  objectVar = tearoffableArg;
+  objectVar = xNonNullArg;
+  objectVar = yNonNullArg;
+  core::num numVar = dynamicArg as{TypeError,ForDynamic,ForNonNullableByDefault} core::num;
+  numVar = numArg;
+  numVar = intArg;
+  numVar = doubleArg;
+  core::int intVar = dynamicArg as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  intVar = intArg;
+  core::double doubleVar = dynamicArg as{TypeError,ForDynamic,ForNonNullableByDefault} core::double;
+  doubleVar = doubleArg;
+  core::Function functionVar = dynamicArg as{TypeError,ForDynamic,ForNonNullableByDefault} core::Function;
+  functionVar = functionArg;
+  functionVar = toVoidArg;
+  functionVar = let final self::Tearoffable #t1 = tearoffableArg in #t1 == null ?{() → void} null : #t1.{self::Tearoffable::call}{() → void};
+  () → void toVoidVar = dynamicArg as{TypeError,ForDynamic,ForNonNullableByDefault} () → void;
+  toVoidVar = toVoidArg;
+  toVoidVar = let final self::Tearoffable #t2 = tearoffableArg in #t2 == null ?{() → void} null : #t2.{self::Tearoffable::call}{() → void};
+  self::Tearoffable tearoffableVar = dynamicArg as{TypeError,ForDynamic,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = tearoffableArg;
+  self::ok::XnonNull xNonNullVar = dynamicArg as{TypeError,ForDynamic,ForNonNullableByDefault} self::ok::XnonNull;
+  xNonNullVar = xNonNullArg;
+  xNonNullVar = yNonNullArg;
+  self::ok::YnonNull yNonNullVar = dynamicArg as{TypeError,ForDynamic,ForNonNullableByDefault} self::ok::YnonNull;
+  yNonNullVar = yNonNullArg;
+  self::ok::XpotentiallyNull% xPotentiallyNullVar = dynamicArg as{TypeError,ForDynamic,ForNonNullableByDefault} self::ok::XpotentiallyNull%;
+  xPotentiallyNullVar = xPotentiallyNullArg;
+  xPotentiallyNullVar = yPotentiallyNullArg;
+  self::ok::YpotentiallyNull% yPotentiallyNullVar = dynamicArg as{TypeError,ForDynamic,ForNonNullableByDefault} self::ok::YpotentiallyNull%;
+  yPotentiallyNullVar = yPotentiallyNullArg;
+}
+static method error<XnonNull extends core::Object, YnonNull extends self::error::XnonNull = core::Object, XpotentiallyNull extends core::Object?, YpotentiallyNull extends self::error::XpotentiallyNull% = core::Object?>(core::Object objectArg, core::Object? objectNullableArg, core::num numArg, core::num? numNullableArg, core::int intArg, core::int? intNullableArg, core::double doubleArg, core::double? doubleNullableArg, core::Function functionArg, core::Function? functionNullableArg, () → void toVoidArg, () →? void toVoidNullableArg, self::Tearoffable tearoffableArg, self::Tearoffable? tearoffableNullableArg, self::error::XnonNull xNonNullArg, self::error::XnonNull? xNonNullNullableArg, self::error::XpotentiallyNull% xPotentiallyNullArg, self::error::XpotentiallyNull? xPotentiallyNullNullableArg, self::error::YnonNull yNonNullArg, self::error::YnonNull? yNonNullNullableArg, self::error::YpotentiallyNull% yPotentiallyNullArg, self::error::YpotentiallyNull? yPotentiallyNullNullableArg) → dynamic {
+  core::Object objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:114:22: Error: A value of type 'Object?' can't be assigned to a variable of type 'Object' because 'Object?' is nullable and 'Object' isn't.
+ - 'Object' is from 'dart:core'.
+  Object objectVar = objectNullableArg;
+                     ^" in objectNullableArg as{TypeError,ForNonNullableByDefault} core::Object;
+  objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:115:15: Error: A value of type 'num?' can't be assigned to a variable of type 'Object' because 'num?' is nullable and 'Object' isn't.
+ - 'Object' is from 'dart:core'.
+  objectVar = numNullableArg;
+              ^" in numNullableArg as{TypeError,ForNonNullableByDefault} core::Object;
+  objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:116:15: Error: A value of type 'int?' can't be assigned to a variable of type 'Object' because 'int?' is nullable and 'Object' isn't.
+ - 'Object' is from 'dart:core'.
+  objectVar = intNullableArg;
+              ^" in intNullableArg as{TypeError,ForNonNullableByDefault} core::Object;
+  objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:117:15: Error: A value of type 'double?' can't be assigned to a variable of type 'Object' because 'double?' is nullable and 'Object' isn't.
+ - 'Object' is from 'dart:core'.
+  objectVar = doubleNullableArg;
+              ^" in doubleNullableArg as{TypeError,ForNonNullableByDefault} core::Object;
+  objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:118:15: Error: A value of type 'Function?' can't be assigned to a variable of type 'Object' because 'Function?' is nullable and 'Object' isn't.
+ - 'Function' is from 'dart:core'.
+ - 'Object' is from 'dart:core'.
+  objectVar = functionNullableArg;
+              ^" in functionNullableArg as{TypeError,ForNonNullableByDefault} core::Object;
+  objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:119:15: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'Object' because 'void Function()?' is nullable and 'Object' isn't.
+ - 'Object' is from 'dart:core'.
+  objectVar = toVoidNullableArg;
+              ^" in toVoidNullableArg as{TypeError,ForNonNullableByDefault} core::Object;
+  objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:120:15: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'Object' because 'Tearoffable?' is nullable and 'Object' isn't.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+ - 'Object' is from 'dart:core'.
+  objectVar = tearoffableNullableArg;
+              ^" in tearoffableNullableArg as{TypeError,ForNonNullableByDefault} core::Object;
+  objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:121:15: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'Object' because 'XnonNull?' is nullable and 'Object' isn't.
+ - 'Object' is from 'dart:core'.
+  objectVar = xNonNullNullableArg;
+              ^" in xNonNullNullableArg as{TypeError,ForNonNullableByDefault} core::Object;
+  objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:122:15: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'Object' because 'XpotentiallyNull' is nullable and 'Object' isn't.
+ - 'Object' is from 'dart:core'.
+  objectVar = xPotentiallyNullArg;
+              ^" in xPotentiallyNullArg as{TypeError,ForNonNullableByDefault} core::Object;
+  objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:123:15: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'Object' because 'XpotentiallyNull?' is nullable and 'Object' isn't.
+ - 'Object' is from 'dart:core'.
+  objectVar = xPotentiallyNullNullableArg;
+              ^" in xPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} core::Object;
+  objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:124:15: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'Object' because 'YnonNull?' is nullable and 'Object' isn't.
+ - 'Object' is from 'dart:core'.
+  objectVar = yNonNullNullableArg;
+              ^" in yNonNullNullableArg as{TypeError,ForNonNullableByDefault} core::Object;
+  objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:125:15: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'Object' because 'YpotentiallyNull' is nullable and 'Object' isn't.
+ - 'Object' is from 'dart:core'.
+  objectVar = yPotentiallyNullArg;
+              ^" in yPotentiallyNullArg as{TypeError,ForNonNullableByDefault} core::Object;
+  objectVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:126:15: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'Object' because 'YpotentiallyNull?' is nullable and 'Object' isn't.
+ - 'Object' is from 'dart:core'.
+  objectVar = yPotentiallyNullNullableArg;
+              ^" in yPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} core::Object;
+  core::num numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:128:16: Error: A value of type 'Object' can't be assigned to a variable of type 'num'.
+ - 'Object' is from 'dart:core'.
+  num numVar = objectArg;
+               ^" in objectArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:129:12: Error: A value of type 'Object?' can't be assigned to a variable of type 'num'.
+ - 'Object' is from 'dart:core'.
+  numVar = objectNullableArg;
+           ^" in objectNullableArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:130:12: Error: A value of type 'num?' can't be assigned to a variable of type 'num' because 'num?' is nullable and 'num' isn't.
+  numVar = numNullableArg;
+           ^" in numNullableArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:131:12: Error: A value of type 'int?' can't be assigned to a variable of type 'num' because 'int?' is nullable and 'num' isn't.
+  numVar = intNullableArg;
+           ^" in intNullableArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:132:12: Error: A value of type 'double?' can't be assigned to a variable of type 'num' because 'double?' is nullable and 'num' isn't.
+  numVar = doubleNullableArg;
+           ^" in doubleNullableArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:133:12: Error: A value of type 'Function' can't be assigned to a variable of type 'num'.
+ - 'Function' is from 'dart:core'.
+  numVar = functionArg;
+           ^" in functionArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:134:12: Error: A value of type 'Function?' can't be assigned to a variable of type 'num'.
+ - 'Function' is from 'dart:core'.
+  numVar = functionNullableArg;
+           ^" in functionNullableArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:135:12: Error: A value of type 'void Function()' can't be assigned to a variable of type 'num'.
+  numVar = toVoidArg;
+           ^" in toVoidArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:136:12: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'num'.
+  numVar = toVoidNullableArg;
+           ^" in toVoidNullableArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:137:12: Error: A value of type 'Tearoffable' can't be assigned to a variable of type 'num'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  numVar = tearoffableArg;
+           ^" in tearoffableArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:138:12: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'num'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  numVar = tearoffableNullableArg;
+           ^" in tearoffableNullableArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:139:12: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'num'.
+  numVar = xNonNullArg;
+           ^" in xNonNullArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:140:12: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'num'.
+  numVar = xNonNullNullableArg;
+           ^" in xNonNullNullableArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:141:12: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'num'.
+  numVar = xPotentiallyNullArg;
+           ^" in xPotentiallyNullArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:142:12: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'num'.
+  numVar = xPotentiallyNullNullableArg;
+           ^" in xPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:143:12: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'num'.
+  numVar = yNonNullArg;
+           ^" in yNonNullArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:144:12: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'num'.
+  numVar = yNonNullNullableArg;
+           ^" in yNonNullNullableArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:145:12: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'num'.
+  numVar = yPotentiallyNullArg;
+           ^" in yPotentiallyNullArg as{TypeError,ForNonNullableByDefault} core::num;
+  numVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:146:12: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'num'.
+  numVar = yPotentiallyNullNullableArg;
+           ^" in yPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} core::num;
+  core::int intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:148:16: Error: A value of type 'Object' can't be assigned to a variable of type 'int'.
+ - 'Object' is from 'dart:core'.
+  int intVar = objectArg;
+               ^" in objectArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:149:12: Error: A value of type 'Object?' can't be assigned to a variable of type 'int'.
+ - 'Object' is from 'dart:core'.
+  intVar = objectNullableArg;
+           ^" in objectNullableArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:150:12: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+  intVar = numArg;
+           ^" in numArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:151:12: Error: A value of type 'num?' can't be assigned to a variable of type 'int'.
+  intVar = numNullableArg;
+           ^" in numNullableArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:152:12: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+  intVar = intNullableArg;
+           ^" in intNullableArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:153:12: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  intVar = doubleArg;
+           ^" in doubleArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:154:12: Error: A value of type 'double?' can't be assigned to a variable of type 'int'.
+  intVar = doubleNullableArg;
+           ^" in doubleNullableArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:155:12: Error: A value of type 'Function' can't be assigned to a variable of type 'int'.
+ - 'Function' is from 'dart:core'.
+  intVar = functionArg;
+           ^" in functionArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:156:12: Error: A value of type 'Function?' can't be assigned to a variable of type 'int'.
+ - 'Function' is from 'dart:core'.
+  intVar = functionNullableArg;
+           ^" in functionNullableArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:157:12: Error: A value of type 'void Function()' can't be assigned to a variable of type 'int'.
+  intVar = toVoidArg;
+           ^" in toVoidArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:158:12: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'int'.
+  intVar = toVoidNullableArg;
+           ^" in toVoidNullableArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:159:12: Error: A value of type 'Tearoffable' can't be assigned to a variable of type 'int'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  intVar = tearoffableArg;
+           ^" in tearoffableArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:160:12: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'int'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  intVar = tearoffableNullableArg;
+           ^" in tearoffableNullableArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:161:12: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'int'.
+  intVar = xNonNullArg;
+           ^" in xNonNullArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:162:12: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'int'.
+  intVar = xNonNullNullableArg;
+           ^" in xNonNullNullableArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:163:12: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'int'.
+  intVar = xPotentiallyNullArg;
+           ^" in xPotentiallyNullArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:164:12: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'int'.
+  intVar = xPotentiallyNullNullableArg;
+           ^" in xPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:165:12: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'int'.
+  intVar = yNonNullArg;
+           ^" in yNonNullArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:166:12: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'int'.
+  intVar = yNonNullNullableArg;
+           ^" in yNonNullNullableArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:167:12: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'int'.
+  intVar = yPotentiallyNullArg;
+           ^" in yPotentiallyNullArg as{TypeError,ForNonNullableByDefault} core::int;
+  intVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:168:12: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'int'.
+  intVar = yPotentiallyNullNullableArg;
+           ^" in yPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} core::int;
+  core::double doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:170:22: Error: A value of type 'Object' can't be assigned to a variable of type 'double'.
+ - 'Object' is from 'dart:core'.
+  double doubleVar = objectArg;
+                     ^" in objectArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:171:15: Error: A value of type 'Object?' can't be assigned to a variable of type 'double'.
+ - 'Object' is from 'dart:core'.
+  doubleVar = objectNullableArg;
+              ^" in objectNullableArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:172:15: Error: A value of type 'num' can't be assigned to a variable of type 'double'.
+  doubleVar = numArg;
+              ^" in numArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:173:15: Error: A value of type 'num?' can't be assigned to a variable of type 'double'.
+  doubleVar = numNullableArg;
+              ^" in numNullableArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:174:15: Error: A value of type 'int' can't be assigned to a variable of type 'double'.
+  doubleVar = intArg;
+              ^" in intArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:175:15: Error: A value of type 'int?' can't be assigned to a variable of type 'double'.
+  doubleVar = intNullableArg;
+              ^" in intNullableArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:176:15: Error: A value of type 'double?' can't be assigned to a variable of type 'double' because 'double?' is nullable and 'double' isn't.
+  doubleVar = doubleNullableArg;
+              ^" in doubleNullableArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:177:15: Error: A value of type 'Function' can't be assigned to a variable of type 'double'.
+ - 'Function' is from 'dart:core'.
+  doubleVar = functionArg;
+              ^" in functionArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:178:15: Error: A value of type 'Function?' can't be assigned to a variable of type 'double'.
+ - 'Function' is from 'dart:core'.
+  doubleVar = functionNullableArg;
+              ^" in functionNullableArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:179:15: Error: A value of type 'void Function()' can't be assigned to a variable of type 'double'.
+  doubleVar = toVoidArg;
+              ^" in toVoidArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:180:15: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'double'.
+  doubleVar = toVoidNullableArg;
+              ^" in toVoidNullableArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:181:15: Error: A value of type 'Tearoffable' can't be assigned to a variable of type 'double'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  doubleVar = tearoffableArg;
+              ^" in tearoffableArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:182:15: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'double'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  doubleVar = tearoffableNullableArg;
+              ^" in tearoffableNullableArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:183:15: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'double'.
+  doubleVar = xNonNullArg;
+              ^" in xNonNullArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:184:15: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'double'.
+  doubleVar = xNonNullNullableArg;
+              ^" in xNonNullNullableArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:185:15: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'double'.
+  doubleVar = xPotentiallyNullArg;
+              ^" in xPotentiallyNullArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:186:15: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'double'.
+  doubleVar = xPotentiallyNullNullableArg;
+              ^" in xPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:187:15: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'double'.
+  doubleVar = yNonNullArg;
+              ^" in yNonNullArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:188:15: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'double'.
+  doubleVar = yNonNullNullableArg;
+              ^" in yNonNullNullableArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:189:15: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'double'.
+  doubleVar = yPotentiallyNullArg;
+              ^" in yPotentiallyNullArg as{TypeError,ForNonNullableByDefault} core::double;
+  doubleVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:190:15: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'double'.
+  doubleVar = yPotentiallyNullNullableArg;
+              ^" in yPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} core::double;
+  core::Function functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:192:26: Error: A value of type 'Object' can't be assigned to a variable of type 'Function'.
+ - 'Object' is from 'dart:core'.
+ - 'Function' is from 'dart:core'.
+  Function functionVar = objectArg;
+                         ^" in objectArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:193:17: Error: A value of type 'Object?' can't be assigned to a variable of type 'Function'.
+ - 'Object' is from 'dart:core'.
+ - 'Function' is from 'dart:core'.
+  functionVar = objectNullableArg;
+                ^" in objectNullableArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:194:17: Error: A value of type 'num' can't be assigned to a variable of type 'Function'.
+ - 'Function' is from 'dart:core'.
+  functionVar = numArg;
+                ^" in numArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:195:17: Error: A value of type 'num?' can't be assigned to a variable of type 'Function'.
+ - 'Function' is from 'dart:core'.
+  functionVar = numNullableArg;
+                ^" in numNullableArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:196:17: Error: A value of type 'int' can't be assigned to a variable of type 'Function'.
+ - 'Function' is from 'dart:core'.
+  functionVar = intArg;
+                ^" in intArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:197:17: Error: A value of type 'int?' can't be assigned to a variable of type 'Function'.
+ - 'Function' is from 'dart:core'.
+  functionVar = intNullableArg;
+                ^" in intNullableArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:198:17: Error: A value of type 'double' can't be assigned to a variable of type 'Function'.
+ - 'Function' is from 'dart:core'.
+  functionVar = doubleArg;
+                ^" in doubleArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:199:17: Error: A value of type 'double?' can't be assigned to a variable of type 'Function'.
+ - 'Function' is from 'dart:core'.
+  functionVar = doubleNullableArg;
+                ^" in doubleNullableArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:200:17: Error: A value of type 'Function?' can't be assigned to a variable of type 'Function' because 'Function?' is nullable and 'Function' isn't.
+ - 'Function' is from 'dart:core'.
+  functionVar = functionNullableArg;
+                ^" in functionNullableArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:201:17: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'Function' because 'void Function()?' is nullable and 'Function' isn't.
+ - 'Function' is from 'dart:core'.
+  functionVar = toVoidNullableArg;
+                ^" in toVoidNullableArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:202:17: Error: Can't tear off method 'call' from a potentially null value.
+  functionVar = tearoffableNullableArg;
+                ^" in tearoffableNullableArg as{TypeError} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:203:17: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'Function'.
+ - 'Function' is from 'dart:core'.
+  functionVar = xNonNullArg;
+                ^" in xNonNullArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:204:17: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'Function'.
+ - 'Function' is from 'dart:core'.
+  functionVar = xNonNullNullableArg;
+                ^" in xNonNullNullableArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:205:17: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'Function'.
+ - 'Function' is from 'dart:core'.
+  functionVar = xPotentiallyNullArg;
+                ^" in xPotentiallyNullArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:206:17: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'Function'.
+ - 'Function' is from 'dart:core'.
+  functionVar = xPotentiallyNullNullableArg;
+                ^" in xPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:207:17: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'Function'.
+ - 'Function' is from 'dart:core'.
+  functionVar = yNonNullArg;
+                ^" in yNonNullArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:208:17: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'Function'.
+ - 'Function' is from 'dart:core'.
+  functionVar = yNonNullNullableArg;
+                ^" in yNonNullNullableArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:209:17: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'Function'.
+ - 'Function' is from 'dart:core'.
+  functionVar = yPotentiallyNullArg;
+                ^" in yPotentiallyNullArg as{TypeError,ForNonNullableByDefault} core::Function;
+  functionVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:210:17: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'Function'.
+ - 'Function' is from 'dart:core'.
+  functionVar = yPotentiallyNullNullableArg;
+                ^" in yPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} core::Function;
+  () → void toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:212:31: Error: A value of type 'Object' can't be assigned to a variable of type 'void Function()'.
+ - 'Object' is from 'dart:core'.
+  void Function() toVoidVar = objectArg;
+                              ^" in objectArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:213:15: Error: A value of type 'Object?' can't be assigned to a variable of type 'void Function()'.
+ - 'Object' is from 'dart:core'.
+  toVoidVar = objectNullableArg;
+              ^" in objectNullableArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:214:15: Error: A value of type 'num' can't be assigned to a variable of type 'void Function()'.
+  toVoidVar = numArg;
+              ^" in numArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:215:15: Error: A value of type 'num?' can't be assigned to a variable of type 'void Function()'.
+  toVoidVar = numNullableArg;
+              ^" in numNullableArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:216:15: Error: A value of type 'int' can't be assigned to a variable of type 'void Function()'.
+  toVoidVar = intArg;
+              ^" in intArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:217:15: Error: A value of type 'int?' can't be assigned to a variable of type 'void Function()'.
+  toVoidVar = intNullableArg;
+              ^" in intNullableArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:218:15: Error: A value of type 'double' can't be assigned to a variable of type 'void Function()'.
+  toVoidVar = doubleArg;
+              ^" in doubleArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:219:15: Error: A value of type 'double?' can't be assigned to a variable of type 'void Function()'.
+  toVoidVar = doubleNullableArg;
+              ^" in doubleNullableArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:220:15: Error: A value of type 'Function' can't be assigned to a variable of type 'void Function()'.
+ - 'Function' is from 'dart:core'.
+  toVoidVar = functionArg;
+              ^" in functionArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:221:15: Error: A value of type 'Function?' can't be assigned to a variable of type 'void Function()'.
+ - 'Function' is from 'dart:core'.
+  toVoidVar = functionNullableArg;
+              ^" in functionNullableArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:222:15: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'void Function()' because 'void Function()?' is nullable and 'void Function()' isn't.
+  toVoidVar = toVoidNullableArg;
+              ^" in toVoidNullableArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:223:15: Error: Can't tear off method 'call' from a potentially null value.
+  toVoidVar = tearoffableNullableArg;
+              ^" in tearoffableNullableArg as{TypeError} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:224:15: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'void Function()'.
+  toVoidVar = xNonNullArg;
+              ^" in xNonNullArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:225:15: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'void Function()'.
+  toVoidVar = xNonNullNullableArg;
+              ^" in xNonNullNullableArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:226:15: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'void Function()'.
+  toVoidVar = xPotentiallyNullArg;
+              ^" in xPotentiallyNullArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:227:15: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'void Function()'.
+  toVoidVar = xPotentiallyNullNullableArg;
+              ^" in xPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:228:15: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'void Function()'.
+  toVoidVar = yNonNullArg;
+              ^" in yNonNullArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:229:15: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'void Function()'.
+  toVoidVar = yNonNullNullableArg;
+              ^" in yNonNullNullableArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:230:15: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'void Function()'.
+  toVoidVar = yPotentiallyNullArg;
+              ^" in yPotentiallyNullArg as{TypeError,ForNonNullableByDefault} () → void;
+  toVoidVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:231:15: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'void Function()'.
+  toVoidVar = yPotentiallyNullNullableArg;
+              ^" in yPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} () → void;
+  self::Tearoffable tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:233:32: Error: A value of type 'Object' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Object' is from 'dart:core'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  Tearoffable tearoffableVar = objectArg;
+                               ^" in objectArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:234:20: Error: A value of type 'Object?' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Object' is from 'dart:core'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = objectNullableArg;
+                   ^" in objectNullableArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:235:20: Error: A value of type 'num' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = numArg;
+                   ^" in numArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:236:20: Error: A value of type 'num?' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = numNullableArg;
+                   ^" in numNullableArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:237:20: Error: A value of type 'int' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = intArg;
+                   ^" in intArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:238:20: Error: A value of type 'int?' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = intNullableArg;
+                   ^" in intNullableArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:239:20: Error: A value of type 'double' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = doubleArg;
+                   ^" in doubleArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:240:20: Error: A value of type 'double?' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = doubleNullableArg;
+                   ^" in doubleNullableArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:241:20: Error: A value of type 'Function' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Function' is from 'dart:core'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = functionArg;
+                   ^" in functionArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:242:20: Error: A value of type 'Function?' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Function' is from 'dart:core'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = functionNullableArg;
+                   ^" in functionNullableArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:243:20: Error: A value of type 'void Function()' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = toVoidArg;
+                   ^" in toVoidArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:244:20: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = toVoidNullableArg;
+                   ^" in toVoidNullableArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:245:20: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'Tearoffable' because 'Tearoffable?' is nullable and 'Tearoffable' isn't.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = tearoffableNullableArg;
+                   ^" in tearoffableNullableArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:246:20: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = xNonNullArg;
+                   ^" in xNonNullArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:247:20: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = xNonNullNullableArg;
+                   ^" in xNonNullNullableArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:248:20: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = xPotentiallyNullArg;
+                   ^" in xPotentiallyNullArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:249:20: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = xPotentiallyNullNullableArg;
+                   ^" in xPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:250:20: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = yNonNullArg;
+                   ^" in yNonNullArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:251:20: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = yNonNullNullableArg;
+                   ^" in yNonNullNullableArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:252:20: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = yPotentiallyNullArg;
+                   ^" in yPotentiallyNullArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  tearoffableVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:253:20: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'Tearoffable'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  tearoffableVar = yPotentiallyNullNullableArg;
+                   ^" in yPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} self::Tearoffable;
+  self::error::XnonNull xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:255:26: Error: A value of type 'Object' can't be assigned to a variable of type 'XnonNull'.
+ - 'Object' is from 'dart:core'.
+  XnonNull xNonNullVar = objectArg;
+                         ^" in objectArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:256:17: Error: A value of type 'Object?' can't be assigned to a variable of type 'XnonNull'.
+ - 'Object' is from 'dart:core'.
+  xNonNullVar = objectNullableArg;
+                ^" in objectNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:257:17: Error: A value of type 'num' can't be assigned to a variable of type 'XnonNull'.
+  xNonNullVar = numArg;
+                ^" in numArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:258:17: Error: A value of type 'num?' can't be assigned to a variable of type 'XnonNull'.
+  xNonNullVar = numNullableArg;
+                ^" in numNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:259:17: Error: A value of type 'int' can't be assigned to a variable of type 'XnonNull'.
+  xNonNullVar = intArg;
+                ^" in intArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:260:17: Error: A value of type 'int?' can't be assigned to a variable of type 'XnonNull'.
+  xNonNullVar = intNullableArg;
+                ^" in intNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:261:17: Error: A value of type 'double' can't be assigned to a variable of type 'XnonNull'.
+  xNonNullVar = doubleArg;
+                ^" in doubleArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:262:17: Error: A value of type 'double?' can't be assigned to a variable of type 'XnonNull'.
+  xNonNullVar = doubleNullableArg;
+                ^" in doubleNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:263:17: Error: A value of type 'Function' can't be assigned to a variable of type 'XnonNull'.
+ - 'Function' is from 'dart:core'.
+  xNonNullVar = functionArg;
+                ^" in functionArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:264:17: Error: A value of type 'Function?' can't be assigned to a variable of type 'XnonNull'.
+ - 'Function' is from 'dart:core'.
+  xNonNullVar = functionNullableArg;
+                ^" in functionNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:265:17: Error: A value of type 'void Function()' can't be assigned to a variable of type 'XnonNull'.
+  xNonNullVar = toVoidArg;
+                ^" in toVoidArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:266:17: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'XnonNull'.
+  xNonNullVar = toVoidNullableArg;
+                ^" in toVoidNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:267:17: Error: A value of type 'Tearoffable' can't be assigned to a variable of type 'XnonNull'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  xNonNullVar = tearoffableArg;
+                ^" in tearoffableArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:268:17: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'XnonNull'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  xNonNullVar = tearoffableNullableArg;
+                ^" in tearoffableNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:269:17: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'XnonNull' because 'XnonNull?' is nullable and 'XnonNull' isn't.
+  xNonNullVar = xNonNullNullableArg;
+                ^" in xNonNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:270:17: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'XnonNull'.
+  xNonNullVar = xPotentiallyNullArg;
+                ^" in xPotentiallyNullArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:271:17: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'XnonNull'.
+  xNonNullVar = xPotentiallyNullNullableArg;
+                ^" in xPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:272:17: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'XnonNull' because 'YnonNull?' is nullable and 'XnonNull' isn't.
+  xNonNullVar = yNonNullNullableArg;
+                ^" in yNonNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:273:17: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'XnonNull'.
+  xNonNullVar = yPotentiallyNullArg;
+                ^" in yPotentiallyNullArg as{TypeError,ForNonNullableByDefault} Never;
+  xNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:274:17: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'XnonNull'.
+  xNonNullVar = yPotentiallyNullNullableArg;
+                ^" in yPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  self::error::XpotentiallyNull% xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:276:42: Error: A value of type 'Object' can't be assigned to a variable of type 'XpotentiallyNull'.
+ - 'Object' is from 'dart:core'.
+  XpotentiallyNull xPotentiallyNullVar = objectArg;
+                                         ^" in objectArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:277:25: Error: A value of type 'Object?' can't be assigned to a variable of type 'XpotentiallyNull'.
+ - 'Object' is from 'dart:core'.
+  xPotentiallyNullVar = objectNullableArg;
+                        ^" in objectNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:278:25: Error: A value of type 'num' can't be assigned to a variable of type 'XpotentiallyNull'.
+  xPotentiallyNullVar = numArg;
+                        ^" in numArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:279:25: Error: A value of type 'num?' can't be assigned to a variable of type 'XpotentiallyNull'.
+  xPotentiallyNullVar = numNullableArg;
+                        ^" in numNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:280:25: Error: A value of type 'int' can't be assigned to a variable of type 'XpotentiallyNull'.
+  xPotentiallyNullVar = intArg;
+                        ^" in intArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:281:25: Error: A value of type 'int?' can't be assigned to a variable of type 'XpotentiallyNull'.
+  xPotentiallyNullVar = intNullableArg;
+                        ^" in intNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:282:25: Error: A value of type 'double' can't be assigned to a variable of type 'XpotentiallyNull'.
+  xPotentiallyNullVar = doubleArg;
+                        ^" in doubleArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:283:25: Error: A value of type 'double?' can't be assigned to a variable of type 'XpotentiallyNull'.
+  xPotentiallyNullVar = doubleNullableArg;
+                        ^" in doubleNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:284:25: Error: A value of type 'Function' can't be assigned to a variable of type 'XpotentiallyNull'.
+ - 'Function' is from 'dart:core'.
+  xPotentiallyNullVar = functionArg;
+                        ^" in functionArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:285:25: Error: A value of type 'Function?' can't be assigned to a variable of type 'XpotentiallyNull'.
+ - 'Function' is from 'dart:core'.
+  xPotentiallyNullVar = functionNullableArg;
+                        ^" in functionNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:286:25: Error: A value of type 'void Function()' can't be assigned to a variable of type 'XpotentiallyNull'.
+  xPotentiallyNullVar = toVoidArg;
+                        ^" in toVoidArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:287:25: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'XpotentiallyNull'.
+  xPotentiallyNullVar = toVoidNullableArg;
+                        ^" in toVoidNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:288:25: Error: A value of type 'Tearoffable' can't be assigned to a variable of type 'XpotentiallyNull'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  xPotentiallyNullVar = tearoffableArg;
+                        ^" in tearoffableArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:289:25: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'XpotentiallyNull'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  xPotentiallyNullVar = tearoffableNullableArg;
+                        ^" in tearoffableNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:290:25: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'XpotentiallyNull'.
+  xPotentiallyNullVar = xNonNullArg;
+                        ^" in xNonNullArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:291:25: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'XpotentiallyNull'.
+  xPotentiallyNullVar = xNonNullNullableArg;
+                        ^" in xNonNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:292:25: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'XpotentiallyNull' because 'XpotentiallyNull?' is nullable and 'XpotentiallyNull' isn't.
+  xPotentiallyNullVar = xPotentiallyNullNullableArg;
+                        ^" in xPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:293:25: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'XpotentiallyNull'.
+  xPotentiallyNullVar = yNonNullArg;
+                        ^" in yNonNullArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:294:25: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'XpotentiallyNull'.
+  xPotentiallyNullVar = yNonNullNullableArg;
+                        ^" in yNonNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  xPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:295:25: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'XpotentiallyNull' because 'YpotentiallyNull?' is nullable and 'XpotentiallyNull' isn't.
+  xPotentiallyNullVar = yPotentiallyNullNullableArg;
+                        ^" in yPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  self::error::YnonNull yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:297:26: Error: A value of type 'Object' can't be assigned to a variable of type 'YnonNull'.
+ - 'Object' is from 'dart:core'.
+  YnonNull yNonNullVar = objectArg;
+                         ^" in objectArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:298:17: Error: A value of type 'Object?' can't be assigned to a variable of type 'YnonNull'.
+ - 'Object' is from 'dart:core'.
+  yNonNullVar = objectNullableArg;
+                ^" in objectNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:299:17: Error: A value of type 'num' can't be assigned to a variable of type 'YnonNull'.
+  yNonNullVar = numArg;
+                ^" in numArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:300:17: Error: A value of type 'num?' can't be assigned to a variable of type 'YnonNull'.
+  yNonNullVar = numNullableArg;
+                ^" in numNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:301:17: Error: A value of type 'int' can't be assigned to a variable of type 'YnonNull'.
+  yNonNullVar = intArg;
+                ^" in intArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:302:17: Error: A value of type 'int?' can't be assigned to a variable of type 'YnonNull'.
+  yNonNullVar = intNullableArg;
+                ^" in intNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:303:17: Error: A value of type 'double' can't be assigned to a variable of type 'YnonNull'.
+  yNonNullVar = doubleArg;
+                ^" in doubleArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:304:17: Error: A value of type 'double?' can't be assigned to a variable of type 'YnonNull'.
+  yNonNullVar = doubleNullableArg;
+                ^" in doubleNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:305:17: Error: A value of type 'Function' can't be assigned to a variable of type 'YnonNull'.
+ - 'Function' is from 'dart:core'.
+  yNonNullVar = functionArg;
+                ^" in functionArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:306:17: Error: A value of type 'Function?' can't be assigned to a variable of type 'YnonNull'.
+ - 'Function' is from 'dart:core'.
+  yNonNullVar = functionNullableArg;
+                ^" in functionNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:307:17: Error: A value of type 'void Function()' can't be assigned to a variable of type 'YnonNull'.
+  yNonNullVar = toVoidArg;
+                ^" in toVoidArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:308:17: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'YnonNull'.
+  yNonNullVar = toVoidNullableArg;
+                ^" in toVoidNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:309:17: Error: A value of type 'Tearoffable' can't be assigned to a variable of type 'YnonNull'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  yNonNullVar = tearoffableArg;
+                ^" in tearoffableArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:310:17: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'YnonNull'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  yNonNullVar = tearoffableNullableArg;
+                ^" in tearoffableNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:311:17: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'YnonNull'.
+  yNonNullVar = xNonNullArg;
+                ^" in xNonNullArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:312:17: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'YnonNull'.
+  yNonNullVar = xNonNullNullableArg;
+                ^" in xNonNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:313:17: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'YnonNull'.
+  yNonNullVar = xPotentiallyNullArg;
+                ^" in xPotentiallyNullArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:314:17: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'YnonNull'.
+  yNonNullVar = xPotentiallyNullNullableArg;
+                ^" in xPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:315:17: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'YnonNull' because 'YnonNull?' is nullable and 'YnonNull' isn't.
+  yNonNullVar = yNonNullNullableArg;
+                ^" in yNonNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:316:17: Error: A value of type 'YpotentiallyNull' can't be assigned to a variable of type 'YnonNull'.
+  yNonNullVar = yPotentiallyNullArg;
+                ^" in yPotentiallyNullArg as{TypeError,ForNonNullableByDefault} Never;
+  yNonNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:317:17: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'YnonNull'.
+  yNonNullVar = yPotentiallyNullNullableArg;
+                ^" in yPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  self::error::YpotentiallyNull% yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:319:42: Error: A value of type 'Object' can't be assigned to a variable of type 'YpotentiallyNull'.
+ - 'Object' is from 'dart:core'.
+  YpotentiallyNull yPotentiallyNullVar = objectArg;
+                                         ^" in objectArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:320:25: Error: A value of type 'Object?' can't be assigned to a variable of type 'YpotentiallyNull'.
+ - 'Object' is from 'dart:core'.
+  yPotentiallyNullVar = objectNullableArg;
+                        ^" in objectNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:321:25: Error: A value of type 'num' can't be assigned to a variable of type 'YpotentiallyNull'.
+  yPotentiallyNullVar = numArg;
+                        ^" in numArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:322:25: Error: A value of type 'num?' can't be assigned to a variable of type 'YpotentiallyNull'.
+  yPotentiallyNullVar = numNullableArg;
+                        ^" in numNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:323:25: Error: A value of type 'int' can't be assigned to a variable of type 'YpotentiallyNull'.
+  yPotentiallyNullVar = intArg;
+                        ^" in intArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:324:25: Error: A value of type 'int?' can't be assigned to a variable of type 'YpotentiallyNull'.
+  yPotentiallyNullVar = intNullableArg;
+                        ^" in intNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:325:25: Error: A value of type 'double' can't be assigned to a variable of type 'YpotentiallyNull'.
+  yPotentiallyNullVar = doubleArg;
+                        ^" in doubleArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:326:25: Error: A value of type 'double?' can't be assigned to a variable of type 'YpotentiallyNull'.
+  yPotentiallyNullVar = doubleNullableArg;
+                        ^" in doubleNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:327:25: Error: A value of type 'Function' can't be assigned to a variable of type 'YpotentiallyNull'.
+ - 'Function' is from 'dart:core'.
+  yPotentiallyNullVar = functionArg;
+                        ^" in functionArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:328:25: Error: A value of type 'Function?' can't be assigned to a variable of type 'YpotentiallyNull'.
+ - 'Function' is from 'dart:core'.
+  yPotentiallyNullVar = functionNullableArg;
+                        ^" in functionNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:329:25: Error: A value of type 'void Function()' can't be assigned to a variable of type 'YpotentiallyNull'.
+  yPotentiallyNullVar = toVoidArg;
+                        ^" in toVoidArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:330:25: Error: A value of type 'void Function()?' can't be assigned to a variable of type 'YpotentiallyNull'.
+  yPotentiallyNullVar = toVoidNullableArg;
+                        ^" in toVoidNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:331:25: Error: A value of type 'Tearoffable' can't be assigned to a variable of type 'YpotentiallyNull'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  yPotentiallyNullVar = tearoffableArg;
+                        ^" in tearoffableArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:332:25: Error: A value of type 'Tearoffable?' can't be assigned to a variable of type 'YpotentiallyNull'.
+ - 'Tearoffable' is from 'pkg/front_end/testcases/nnbd/assignability.dart'.
+  yPotentiallyNullVar = tearoffableNullableArg;
+                        ^" in tearoffableNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:333:25: Error: A value of type 'XnonNull' can't be assigned to a variable of type 'YpotentiallyNull'.
+  yPotentiallyNullVar = xNonNullArg;
+                        ^" in xNonNullArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:334:25: Error: A value of type 'XnonNull?' can't be assigned to a variable of type 'YpotentiallyNull'.
+  yPotentiallyNullVar = xNonNullNullableArg;
+                        ^" in xNonNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:335:25: Error: A value of type 'XpotentiallyNull' can't be assigned to a variable of type 'YpotentiallyNull'.
+  yPotentiallyNullVar = xPotentiallyNullArg;
+                        ^" in xPotentiallyNullArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:336:25: Error: A value of type 'XpotentiallyNull?' can't be assigned to a variable of type 'YpotentiallyNull'.
+  yPotentiallyNullVar = xPotentiallyNullNullableArg;
+                        ^" in xPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:337:25: Error: A value of type 'YnonNull' can't be assigned to a variable of type 'YpotentiallyNull'.
+  yPotentiallyNullVar = yNonNullArg;
+                        ^" in yNonNullArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:338:25: Error: A value of type 'YnonNull?' can't be assigned to a variable of type 'YpotentiallyNull'.
+  yPotentiallyNullVar = yNonNullNullableArg;
+                        ^" in yNonNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+  yPotentiallyNullVar = invalid-expression "pkg/front_end/testcases/nnbd/assignability.dart:339:25: Error: A value of type 'YpotentiallyNull?' can't be assigned to a variable of type 'YpotentiallyNull' because 'YpotentiallyNull?' is nullable and 'YpotentiallyNull' isn't.
+  yPotentiallyNullVar = yPotentiallyNullNullableArg;
+                        ^" in yPotentiallyNullNullableArg as{TypeError,ForNonNullableByDefault} Never;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/assignability_error_messages.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/assignability_error_messages.dart.weak.modular.expect
new file mode 100644
index 0000000..1f4c1bb
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/assignability_error_messages.dart.weak.modular.expect
@@ -0,0 +1,393 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:27:14: Error: The argument type 'B?' can't be assigned to the parameter type 'A' because 'B?' is nullable and 'A' isn't.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   fooContext(x); // Error.
+//              ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:28:9: Error: A value of type 'B?' can't be assigned to a variable of type 'A' because 'B?' is nullable and 'A' isn't.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   A a = x; // Error.
+//         ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:29:10: Error: Can't assign spread elements of type 'B?' to collection elements of type 'A' because 'B?' is nullable and 'A' isn't.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   <A>[...l]; // Error.
+//          ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:30:10: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//   <A>[...l2]; // Error.
+//          ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:31:13: Error: Can't assign spread entry keys of type 'B?' to map entry keys of type 'A' because 'B?' is nullable and 'A' isn't.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   <A, A>{...m}; // Error.
+//             ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:31:13: Error: Can't assign spread entry values of type 'B?' to map entry values of type 'A' because 'B?' is nullable and 'A' isn't.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   <A, A>{...m}; // Error.
+//             ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:32:13: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//   <A, A>{...m2}; // Error.
+//             ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:33:10: Error: A value of type 'B?' can't be assigned to a variable of type 'A' because 'B?' is nullable and 'A' isn't.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+// Try changing the type of the variable.
+//   for (A y in l) {} // Error.
+//          ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:34:15: Error: The type 'List<B>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'List<B>?' is nullable and 'Iterable<dynamic>' isn't.
+//  - 'List' is from 'dart:core'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'Iterable' is from 'dart:core'.
+//   for (A y in l2) {} // Error.
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:36:16: Error: Type 'A' of the case expression is not a subtype of type 'B?' of this switch expression.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//     case const A():
+//                ^
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:35:11: Context: The switch expression is here.
+//   switch (x) /*  Error. */ {
+//           ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:43:14: Error: A value of type 'B?' can't be returned from an async function with return type 'FutureOr<A>' because 'B?' is nullable and 'FutureOr<A>' isn't.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//       return x; // Error.
+//              ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:45:18: Error: A value of type 'Future<B?>' can't be returned from an async function with return type 'FutureOr<A>'.
+//  - 'Future' is from 'dart:async'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//       return new Future<B?>.value(x); // Error.
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:49:10: Error: A value of type 'B?' can't be returned from a function with return type 'A' because 'B?' is nullable and 'A' isn't.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   return x; // Error.
+//          ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:53:14: Error: The argument type 'List<B?>' can't be assigned to the parameter type 'List<A>' because 'B?' is nullable and 'A' isn't.
+//  - 'List' is from 'dart:core'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   barContext(x); // Error.
+//              ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:54:15: Error: A value of type 'List<B?>' can't be assigned to a variable of type 'List<A>' because 'B?' is nullable and 'A' isn't.
+//  - 'List' is from 'dart:core'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   List<A> y = x; // Error.
+//               ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:55:16: Error: Can't assign spread elements of type 'List<B?>' to collection elements of type 'List<A>' because 'B?' is nullable and 'A' isn't.
+//  - 'List' is from 'dart:core'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   <List<A>>[...l]; // Error.
+//                ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:56:25: Error: Can't assign spread entry keys of type 'List<B?>' to map entry keys of type 'List<A>' because 'B?' is nullable and 'A' isn't.
+//  - 'List' is from 'dart:core'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   <List<A>, List<A>>{...m}; // Error.
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:56:25: Error: Can't assign spread entry values of type 'List<B?>' to map entry values of type 'List<A>' because 'B?' is nullable and 'A' isn't.
+//  - 'List' is from 'dart:core'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   <List<A>, List<A>>{...m}; // Error.
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:57:16: Error: A value of type 'List<B?>' can't be assigned to a variable of type 'List<A>' because 'B?' is nullable and 'A' isn't.
+//  - 'List' is from 'dart:core'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+// Try changing the type of the variable.
+//   for (List<A> y in l) {} // Error.
+//                ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:58:10: Error: A value of type 'List<B?>' can't be returned from a function with return type 'List<A>' because 'B?' is nullable and 'A' isn't.
+//  - 'List' is from 'dart:core'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   return x; // Error.
+//          ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:62:14: Error: The argument type 'num? Function()' can't be assigned to the parameter type 'num Function()' because 'num?' is nullable and 'num' isn't.
+//   bazContext(c);
+//              ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:66:14: Error: The argument type 'Null' can't be assigned to the parameter type 'A' because 'A' is not nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   fooContext(x); // Error.
+//              ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:67:14: Error: The value 'null' can't be assigned to the parameter type 'A' because 'A' is not nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   fooContext(null); // Error.
+//              ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:68:10: Error: A value of type 'Null' can't be assigned to a variable of type 'A' because 'A' is not nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   A a1 = x; // Error.
+//          ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:69:10: Error: The value 'null' can't be assigned to a variable of type 'A' because 'A' is not nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//   A a2 = null; // Error.
+//          ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:71:12: Error: A value of type 'Null' can't be returned from a function with return type 'A' because 'A' is not nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//     return x; // Error.
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:73:12: Error: The value 'null' can't be returned from a function with return type 'A' because 'A' is not nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//     return null; // Error.
+//            ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:77:14: Error: The value 'null' can't be returned from an async function with return type 'FutureOr<A>' because 'FutureOr<A>' is not nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//       return null; // Error.
+//              ^
+//
+// pkg/front_end/testcases/nnbd/assignability_error_messages.dart:79:18: Error: A value of type 'Future<Null>' can't be returned from an async function with return type 'FutureOr<A>'.
+//  - 'Future' is from 'dart:async'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+//       return new Future<Null>.value(null); // Error.
+//                  ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class B extends self::A {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  method call() → core::num? {}
+}
+static method fooContext(self::A x) → void {}
+static method barContext(core::List<self::A> x) → void {}
+static method bazContext(() → core::num f) → void {}
+static method foo(self::B? x, core::List<self::B?> l, core::Map<self::B?, self::B?> m, core::List<self::B>? l2, core::Map<self::B, self::B>? m2) → self::A {
+  self::fooContext(invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:27:14: Error: The argument type 'B?' can't be assigned to the parameter type 'A' because 'B?' is nullable and 'A' isn't.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  fooContext(x); // Error.
+             ^" in x as{TypeError,ForNonNullableByDefault} self::A);
+  self::A a = invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:28:9: Error: A value of type 'B?' can't be assigned to a variable of type 'A' because 'B?' is nullable and 'A' isn't.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  A a = x; // Error.
+        ^" in x as{TypeError,ForNonNullableByDefault} self::A;
+  <self::A>[invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:29:10: Error: Can't assign spread elements of type 'B?' to collection elements of type 'A' because 'B?' is nullable and 'A' isn't.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  <A>[...l]; // Error.
+         ^"];
+  <self::A>[invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:30:10: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+  <A>[...l2]; // Error.
+         ^"];
+  <self::A, self::A>{invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:31:13: Error: Can't assign spread entry keys of type 'B?' to map entry keys of type 'A' because 'B?' is nullable and 'A' isn't.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  <A, A>{...m}; // Error.
+            ^": invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:31:13: Error: Can't assign spread entry values of type 'B?' to map entry values of type 'A' because 'B?' is nullable and 'A' isn't.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  <A, A>{...m}; // Error.
+            ^"};
+  <self::A, self::A>{invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:32:13: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+  <A, A>{...m2}; // Error.
+            ^": null};
+  for (final self::B? #t1 in l) {
+    self::A y = invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:33:10: Error: A value of type 'B?' can't be assigned to a variable of type 'A' because 'B?' is nullable and 'A' isn't.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+Try changing the type of the variable.
+  for (A y in l) {} // Error.
+         ^" in #t1 as{TypeError,ForNonNullableByDefault} self::A;
+  }
+  for (self::A y in invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:34:15: Error: The type 'List<B>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'List<B>?' is nullable and 'Iterable<dynamic>' isn't.
+ - 'List' is from 'dart:core'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'Iterable' is from 'dart:core'.
+  for (A y in l2) {} // Error.
+              ^" in l2 as{TypeError,ForNonNullableByDefault} core::Iterable<dynamic>) {
+  }
+  #L1:
+  switch(x) {
+    #L2:
+    case #C1:
+      {
+        break #L1;
+      }
+    #L3:
+    default:
+      {
+        break #L1;
+      }
+  }
+  function local() → FutureOr<self::A> async {
+    if(true) {
+      return invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:43:14: Error: A value of type 'B?' can't be returned from an async function with return type 'FutureOr<A>' because 'B?' is nullable and 'FutureOr<A>' isn't.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+      return x; // Error.
+             ^" in x as{TypeError,ForNonNullableByDefault} self::A;
+    }
+    else {
+      return invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:45:18: Error: A value of type 'Future<B?>' can't be returned from an async function with return type 'FutureOr<A>'.
+ - 'Future' is from 'dart:async'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+      return new Future<B?>.value(x); // Error.
+                 ^" in asy::Future::value<self::B?>(x) as{TypeError,ForNonNullableByDefault} self::A;
+    }
+  }
+  return invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:49:10: Error: A value of type 'B?' can't be returned from a function with return type 'A' because 'B?' is nullable and 'A' isn't.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  return x; // Error.
+         ^" in x as{TypeError,ForNonNullableByDefault} self::A;
+}
+static method bar(core::List<self::B?> x, core::List<core::List<self::B?>> l, core::Map<core::List<self::B?>, core::List<self::B?>> m) → core::List<self::A> {
+  self::barContext(invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:53:14: Error: The argument type 'List<B?>' can't be assigned to the parameter type 'List<A>' because 'B?' is nullable and 'A' isn't.
+ - 'List' is from 'dart:core'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  barContext(x); // Error.
+             ^" in x as{TypeError,ForNonNullableByDefault} core::List<self::A>);
+  core::List<self::A> y = invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:54:15: Error: A value of type 'List<B?>' can't be assigned to a variable of type 'List<A>' because 'B?' is nullable and 'A' isn't.
+ - 'List' is from 'dart:core'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  List<A> y = x; // Error.
+              ^" in x as{TypeError,ForNonNullableByDefault} core::List<self::A>;
+  <core::List<self::A>>[invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:55:16: Error: Can't assign spread elements of type 'List<B?>' to collection elements of type 'List<A>' because 'B?' is nullable and 'A' isn't.
+ - 'List' is from 'dart:core'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  <List<A>>[...l]; // Error.
+               ^"];
+  <core::List<self::A>, core::List<self::A>>{invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:56:25: Error: Can't assign spread entry keys of type 'List<B?>' to map entry keys of type 'List<A>' because 'B?' is nullable and 'A' isn't.
+ - 'List' is from 'dart:core'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  <List<A>, List<A>>{...m}; // Error.
+                        ^": invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:56:25: Error: Can't assign spread entry values of type 'List<B?>' to map entry values of type 'List<A>' because 'B?' is nullable and 'A' isn't.
+ - 'List' is from 'dart:core'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  <List<A>, List<A>>{...m}; // Error.
+                        ^"};
+  for (final core::List<self::B?> #t2 in l) {
+    core::List<self::A> y = invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:57:16: Error: A value of type 'List<B?>' can't be assigned to a variable of type 'List<A>' because 'B?' is nullable and 'A' isn't.
+ - 'List' is from 'dart:core'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+Try changing the type of the variable.
+  for (List<A> y in l) {} // Error.
+               ^" in #t2 as{TypeError,ForNonNullableByDefault} core::List<self::A>;
+  }
+  return invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:58:10: Error: A value of type 'List<B?>' can't be returned from a function with return type 'List<A>' because 'B?' is nullable and 'A' isn't.
+ - 'List' is from 'dart:core'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  return x; // Error.
+         ^" in x as{TypeError,ForNonNullableByDefault} core::List<self::A>;
+}
+static method baz(self::C c) → void {
+  self::bazContext(invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:62:14: Error: The argument type 'num? Function()' can't be assigned to the parameter type 'num Function()' because 'num?' is nullable and 'num' isn't.
+  bazContext(c);
+             ^" in (let final self::C #t3 = c in #t3 == null ?{() → core::num?} null : #t3.{self::C::call}{() → core::num?}) as{TypeError,ForNonNullableByDefault} () → core::num);
+}
+static method boz(Null x) → self::A {
+  self::fooContext(invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:66:14: Error: The argument type 'Null' can't be assigned to the parameter type 'A' because 'A' is not nullable.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  fooContext(x); // Error.
+             ^" in x as{TypeError,ForNonNullableByDefault} self::A);
+  self::fooContext(invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:67:14: Error: The value 'null' can't be assigned to the parameter type 'A' because 'A' is not nullable.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  fooContext(null); // Error.
+             ^" in null as{TypeError,ForNonNullableByDefault} self::A);
+  self::A a1 = invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:68:10: Error: A value of type 'Null' can't be assigned to a variable of type 'A' because 'A' is not nullable.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  A a1 = x; // Error.
+         ^" in x as{TypeError,ForNonNullableByDefault} self::A;
+  self::A a2 = invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:69:10: Error: The value 'null' can't be assigned to a variable of type 'A' because 'A' is not nullable.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+  A a2 = null; // Error.
+         ^" in null as{TypeError,ForNonNullableByDefault} self::A;
+  if(true) {
+    return invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:71:12: Error: A value of type 'Null' can't be returned from a function with return type 'A' because 'A' is not nullable.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+    return x; // Error.
+           ^" in x as{TypeError,ForNonNullableByDefault} self::A;
+  }
+  else {
+    return invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:73:12: Error: The value 'null' can't be returned from a function with return type 'A' because 'A' is not nullable.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+    return null; // Error.
+           ^" in null as{TypeError,ForNonNullableByDefault} self::A;
+  }
+  function local() → FutureOr<self::A> async {
+    if(true) {
+      return invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:77:14: Error: The value 'null' can't be returned from an async function with return type 'FutureOr<A>' because 'FutureOr<A>' is not nullable.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+      return null; // Error.
+             ^" in null as{TypeError,ForNonNullableByDefault} self::A;
+    }
+    else {
+      return invalid-expression "pkg/front_end/testcases/nnbd/assignability_error_messages.dart:79:18: Error: A value of type 'Future<Null>' can't be returned from an async function with return type 'FutureOr<A>'.
+ - 'Future' is from 'dart:async'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/assignability_error_messages.dart'.
+      return new Future<Null>.value(null); // Error.
+                 ^" in asy::Future::value<Null>(null) as{TypeError,ForNonNullableByDefault} self::A;
+    }
+  }
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::A {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///assignability_error_messages.dart:
+- A. (from org-dartlang-testcase:///assignability_error_messages.dart:11:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/bounds_checks.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/bounds_checks.dart.weak.modular.expect
new file mode 100644
index 0000000..ab741a5
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/bounds_checks.dart.weak.modular.expect
@@ -0,0 +1,91 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/bounds_checks.dart:7:13: Error: Type argument 'num?' doesn't conform to the bound 'num' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+// foo(A<num?> a) {} // Error
+//             ^
+// pkg/front_end/testcases/nnbd/bounds_checks.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/bounds_checks.dart:9:13: Error: Type argument 'num?' doesn't conform to the bound 'num' of the type variable 'X' on 'A' in the return type.
+// Try changing type arguments so that they conform to the bounds.
+// A<num?>? bar() {} // Error
+//             ^
+// pkg/front_end/testcases/nnbd/bounds_checks.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/bounds_checks.dart:11:5: Error: Type argument 'num?' doesn't conform to the bound 'num' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+// baz<T extends A<num?>>() {} // Error
+//     ^
+// pkg/front_end/testcases/nnbd/bounds_checks.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/bounds_checks.dart:13:7: Error: Type argument 'num?' doesn't conform to the bound 'num' of the type variable 'X' on 'A' in the supertype 'A' of class 'B'.
+// Try changing type arguments so that they conform to the bounds.
+// class B extends A<num?> {} // Error
+//       ^
+// pkg/front_end/testcases/nnbd/bounds_checks.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/bounds_checks.dart:15:9: Error: Type argument 'num?' doesn't conform to the bound 'num' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+// class C<T extends A<num?>> {} // Error
+//         ^
+// pkg/front_end/testcases/nnbd/bounds_checks.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/bounds_checks.dart:24:3: Error: Type argument 'num?' doesn't conform to the bound 'num' of the type variable 'T' on 'hest'.
+// Try changing type arguments so that they conform to the bounds.
+//   hest<num?>();
+//   ^
+// pkg/front_end/testcases/nnbd/bounds_checks.dart:17:11: Context: This is the type variable whose bound isn't conformed to.
+// void hest<T extends num>() {}
+//           ^
+//
+// pkg/front_end/testcases/nnbd/bounds_checks.dart:25:5: Error: Type argument 'num?' doesn't conform to the bound 'num' of the type variable 'T' on 'Hest.hest'.
+//  - 'Hest' is from 'pkg/front_end/testcases/nnbd/bounds_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   h.hest<num?>();
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::num> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X>
+    : super core::Object::•()
+    ;
+}
+class B extends self::A<core::num?> {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+}
+class C<T extends self::A<core::num?>> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T>
+    : super core::Object::•()
+    ;
+}
+class Hest extends core::Object {
+  synthetic constructor •() → self::Hest
+    : super core::Object::•()
+    ;
+  method hest<T extends core::num>() → void {}
+}
+static method foo(self::A<core::num?> a) → dynamic {}
+static method bar() → self::A<core::num?>? {}
+static method baz<T extends self::A<core::num?>>() → dynamic {}
+static method hest<T extends core::num>() → void {}
+static method fisk(self::Hest h) → dynamic {
+  self::hest<core::num?>();
+  h.{self::Hest::hest}<core::num?>(){() → void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/build_issue_2688.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/build_issue_2688.dart.weak.modular.expect
new file mode 100644
index 0000000..2ae4ce3
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/build_issue_2688.dart.weak.modular.expect
@@ -0,0 +1,270 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class M0 extends core::Object /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M1 extends core::Object implements self::M0 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M2 extends core::Object implements self::M1 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M3 extends core::Object implements self::M2 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M4 extends core::Object implements self::M3 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M5 extends core::Object implements self::M4 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M6 extends core::Object implements self::M5 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M7 extends core::Object implements self::M6 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M8 extends core::Object implements self::M7 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M9 extends core::Object implements self::M8 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M10 extends core::Object implements self::M9 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M11 extends core::Object implements self::M10 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M12 extends core::Object implements self::M11 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M13 extends core::Object implements self::M12 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M14 extends core::Object implements self::M13 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M15 extends core::Object implements self::M14 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M16 extends core::Object implements self::M15 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M17 extends core::Object implements self::M16 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M18 extends core::Object implements self::M17 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M19 extends core::Object implements self::M18 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M20 extends core::Object implements self::M19 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M21 extends core::Object implements self::M20 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M22 extends core::Object implements self::M21 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M23 extends core::Object implements self::M22 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M24 extends core::Object implements self::M23 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M25 extends core::Object implements self::M24 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M26 extends core::Object implements self::M25 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class M27 extends core::Object implements self::M26 /*isMixinDeclaration*/  {
+  abstract get property() → core::int;
+}
+abstract class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  abstract get property() → core::int;
+}
+abstract class _Class&Super&M0 = self::Super with self::M0 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0
+    : super self::Super::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M0::property
+}
+abstract class _Class&Super&M0&M1 = self::_Class&Super&M0 with self::M1 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1
+    : super self::_Class&Super&M0::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M1::property
+}
+abstract class _Class&Super&M0&M1&M2 = self::_Class&Super&M0&M1 with self::M2 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2
+    : super self::_Class&Super&M0&M1::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M2::property
+}
+abstract class _Class&Super&M0&M1&M2&M3 = self::_Class&Super&M0&M1&M2 with self::M3 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3
+    : super self::_Class&Super&M0&M1&M2::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M3::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4 = self::_Class&Super&M0&M1&M2&M3 with self::M4 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4
+    : super self::_Class&Super&M0&M1&M2&M3::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M4::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5 = self::_Class&Super&M0&M1&M2&M3&M4 with self::M5 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5
+    : super self::_Class&Super&M0&M1&M2&M3&M4::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M5::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6 = self::_Class&Super&M0&M1&M2&M3&M4&M5 with self::M6 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M6::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6 with self::M7 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M7::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7 with self::M8 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M8::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8 with self::M9 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M9::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9 with self::M10 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M10::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10 with self::M11 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M11::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11 with self::M12 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M12::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12 with self::M13 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M13::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13 with self::M14 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M14::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14 with self::M15 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M15::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15 with self::M16 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M16::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16 with self::M17 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M17::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17 with self::M18 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M18::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18 with self::M19 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M19::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19 with self::M20 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M20::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20 with self::M21 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M21::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21 with self::M22 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M22::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22 with self::M23 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M23::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23 with self::M24 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M24::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24 with self::M25 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M25::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25 with self::M26 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M26::property
+}
+abstract class _Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26&M27 = self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26 with self::M27 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26&M27
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26::•()
+    ;
+  abstract mixin-stub get property() → core::int; -> self::M27::property
+}
+class Class extends self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26&M27 {
+  synthetic constructor •() → self::Class
+    : super self::_Class&Super&M0&M1&M2&M3&M4&M5&M6&M7&M8&M9&M10&M11&M12&M13&M14&M15&M16&M17&M18&M19&M20&M21&M22&M23&M24&M25&M26&M27::•()
+    ;
+  get property() → core::int
+    return 0;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/call.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/call.dart.weak.modular.expect
new file mode 100644
index 0000000..e93db55
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/call.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/call.dart:12:4: Error: Can't use an expression of type 'void Function()?' as a function because it's potentially null.
+// Try calling using ?.call instead.
+//   f();
+//    ^
+//
+// pkg/front_end/testcases/nnbd/call.dart:13:5: Error: Method 'call' cannot be called on 'void Function()?' because it is potentially null.
+// Try calling using ?. instead.
+//   f.call();
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/call.dart:15:10: Error: Can't use an expression of type 'void Function()?' as a function because it's potentially null.
+// Try calling using ?.call instead.
+//   c.field();
+//          ^
+//
+// pkg/front_end/testcases/nnbd/call.dart:16:11: Error: Can't use an expression of type 'void Function()?' as a function because it's potentially null.
+// Try calling using ?.call instead.
+//   c.getter();
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field () →? void field = null;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  get getter() → () →? void
+    return null;
+}
+static method error() → dynamic {
+  () →? void f;
+  invalid-expression "pkg/front_end/testcases/nnbd/call.dart:12:4: Error: Can't use an expression of type 'void Function()?' as a function because it's potentially null.
+Try calling using ?.call instead.
+  f();
+   ^" in f{<nullable>}.(){() →? void};
+  invalid-expression "pkg/front_end/testcases/nnbd/call.dart:13:5: Error: Method 'call' cannot be called on 'void Function()?' because it is potentially null.
+Try calling using ?. instead.
+  f.call();
+    ^^^^" in f{<nullable>}.(){() →? void};
+  self::Class c = new self::Class::•();
+  invalid-expression "pkg/front_end/testcases/nnbd/call.dart:15:10: Error: Can't use an expression of type 'void Function()?' as a function because it's potentially null.
+Try calling using ?.call instead.
+  c.field();
+         ^" in c.{self::Class::field}{() →? void}{<nullable>}.(){() →? void};
+  invalid-expression "pkg/front_end/testcases/nnbd/call.dart:16:11: Error: Can't use an expression of type 'void Function()?' as a function because it's potentially null.
+Try calling using ?.call instead.
+  c.getter();
+          ^" in c.{self::Class::getter}{() →? void}{<nullable>}.(){() →? void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/combined_required.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/combined_required.dart.weak.modular.expect
new file mode 100644
index 0000000..4e4e563
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/combined_required.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method method1({required core::int a = #C1}) → void {}
+  method method2({core::int? a = #C1, required core::int b = #C1}) → void {}
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+  method method1({required covariant-by-declaration core::int a = #C1}) → void {}
+  method method2({covariant-by-declaration core::int? a = #C1, required core::int b = #C1}) → void {}
+}
+class C extends self::A implements self::B {
+  synthetic constructor •() → self::C
+    : super self::A::•()
+    ;
+  forwarding-stub method method1({required covariant-by-declaration core::int a = #C1}) → void
+    return super.{self::A::method1}(a: a);
+  forwarding-stub method method2({covariant-by-declaration core::int? a = #C1, required core::int b = #C1}) → void
+    return super.{self::A::method2}(a: a, b: b);
+}
+class D extends self::C {
+  synthetic constructor •() → self::D
+    : super self::C::•()
+    ;
+  method method1({required covariant-by-declaration core::int a = #C1}) → void {}
+  method method2({covariant-by-declaration core::int? a = #C1, required core::int b = #C1}) → void {}
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/const_canonical_type.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/const_canonical_type.dart.weak.modular.expect
new file mode 100644
index 0000000..5e1af23
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/const_canonical_type.dart.weak.modular.expect
@@ -0,0 +1,64 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+typedef F1 = () → self::A<FutureOr<dynamic>>;
+typedef F2 = () → self::A<dynamic>;
+typedef F3 = () → self::A<FutureOr<FutureOr<dynamic>?>>;
+typedef F4 = () → self::A<dynamic>;
+class Check extends core::Object /*hasConstConstructor*/  {
+  final field dynamic _ignored;
+  const constructor •(dynamic x, dynamic y) → self::Check
+    : assert(core::identical(x, y)), self::Check::_ignored = core::identical(x, y) ?{core::int} 42 : 1.{core::num::~/}(0){(core::num) → core::int}, super core::Object::•()
+    ;
+}
+class A<X extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+}
+static method expectEqual(dynamic x, dynamic y) → void {
+  if(!(x =={core::Object::==}{(core::Object) → core::bool} y)) {
+    throw "Arguments were supposed to be identical.";
+  }
+}
+static method test1() → dynamic {
+  core::Type v = #C1;
+  self::expectEqual(#C1, #C1);
+  self::expectEqual(#C1, #C1);
+  self::expectEqual(#C1, #C1);
+  self::expectEqual(v, v);
+  self::expectEqual(v, #C1);
+  core::Type vf1 = #C2;
+  core::Type vf2 = #C2;
+  core::Type vf3 = #C2;
+  core::Type vf4 = #C2;
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, vf1);
+  self::expectEqual(vf1, vf2);
+  self::expectEqual(vf2, vf3);
+  self::expectEqual(vf3, vf4);
+  return #C5;
+}
+static method main() → dynamic {
+  self::test1();
+}
+
+constants  {
+  #C1 = TypeLiteralConstant(self::A<dynamic>*)
+  #C2 = TypeLiteralConstant(() →* self::A<dynamic>*)
+  #C3 = 42
+  #C4 = self::Check {_ignored:#C3}
+  #C5 = <dynamic>[#C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///const_canonical_type.dart:
+- A. (from org-dartlang-testcase:///const_canonical_type.dart:22:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Check. (from org-dartlang-testcase:///const_canonical_type.dart:10:9)
diff --git a/pkg/front_end/testcases/nnbd/const_is.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/const_is.dart.weak.modular.expect
new file mode 100644
index 0000000..81ac3c3
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/const_is.dart.weak.modular.expect
@@ -0,0 +1,106 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef fType = ({required i: core::int}) → core::int;
+typedef gType = ({i: core::int}) → core::int;
+typedef bigType = ({required i1: core::int, required i10: core::int, required i11: core::int, required i12: core::int, required i13: core::int, required i14: core::int, required i15: core::int, required i16: core::int, required i17: core::int, required i18: core::int, required i19: core::int, required i2: core::int, required i20: core::int, required i21: core::int, required i22: core::int, required i23: core::int, required i24: core::int, required i25: core::int, required i26: core::int, required i27: core::int, required i28: core::int, required i29: core::int, required i3: core::int, required i30: core::int, required i31: core::int, required i32: core::int, required i33: core::int, required i34: core::int, required i35: core::int, required i36: core::int, required i37: core::int, required i38: core::int, required i39: core::int, required i4: core::int, required i40: core::int, required i41: core::int, required i42: core::int, required i43: core::int, required i44: core::int, required i45: core::int, required i46: core::int, required i47: core::int, required i48: core::int, required i49: core::int, required i5: core::int, required i50: core::int, required i51: core::int, required i52: core::int, required i53: core::int, required i54: core::int, required i55: core::int, required i56: core::int, required i57: core::int, required i58: core::int, required i59: core::int, required i6: core::int, required i60: core::int, required i61: core::int, required i62: core::int, required i63: core::int, required i64: core::int, required i65: core::int, required i66: core::int, required i67: core::int, required i68: core::int, required i69: core::int, required i7: core::int, required i70: core::int, required i8: core::int, required i9: core::int}) → core::int;
+typedef func = (core::Object) → self::B;
+typedef t1 = (core::int, self::B, core::Map<core::int, core::num>, dynamic, {required ob: self::B, required obool: core::bool, required ol: core::List<core::num>, required ox: dynamic}) → self::B;
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class A1 extends core::Object {
+  synthetic constructor •() → self::A1
+    : super core::Object::•()
+    ;
+}
+class A2 extends core::Object {
+  synthetic constructor •() → self::A2
+    : super core::Object::•()
+    ;
+}
+class B extends core::Object implements self::A, self::A1, self::A2 {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+}
+class C extends core::Object implements self::B {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+class D extends core::Object implements self::C {
+  synthetic constructor •() → self::D
+    : super core::Object::•()
+    ;
+}
+static field core::bool inStrongMode = !(<core::int?>[] is{ForNonNullableByDefault} core::List<core::int>);
+static const field core::bool f_is_fType = #C1;
+static const field core::bool f_is_gType = #C1;
+static const field core::bool g_is_fType = #C1;
+static const field core::bool g_is_gType = #C1;
+static const field core::bool f_is_bigType = #C2;
+static const field core::bool f1_is_t1 = #C2;
+static const field core::bool f2_is_t1 = #C2;
+static const field core::bool f3_is_t1 = #C1;
+static const field core::bool f4_is_t1 = #C1;
+static const field core::bool f5_is_t1 = #C1;
+static method f({required core::int i = #C3}) → core::int {
+  return i.{core::num::+}(1){(core::num) → core::int};
+}
+static method g({core::int i = #C4}) → core::int {
+  return i.{core::num::+}(1){(core::num) → core::int};
+}
+static method f1(core::int i, self::B b, core::Map<core::int, core::num> m, dynamic x, {required dynamic extraParam = #C3, required core::bool obool = #C3, required dynamic ox = #C3, required self::D ob = #C3, required core::List<core::num>? ol = #C3}) → self::B
+  return new self::B::•();
+static method f2(core::int i, self::D b, core::Map<core::int, core::int> m, (core::Object) → self::B x, {required (core::Object) → self::B ox = #C3, required self::D ob = #C3, required core::List<core::int> ol = #C3, required core::bool obool = #C3}) → self::D
+  return new self::D::•();
+static method f3(core::num i, self::A b, core::Map<core::Object, core::Object> m, dynamic x, {required dynamic ox = #C3, required dynamic extraParam = #C3, required self::A2 ob = #C3, required core::List<dynamic> ol = #C3, required core::Object obool = #C3}) → self::C
+  return new self::C::•();
+static method f4(core::num i, self::A b, core::Map<core::Object, core::Object> m, dynamic x, {required dynamic ox = #C3, required self::A2 ob = #C3, required core::List<dynamic> ol = #C3, required core::bool obool = #C3, required self::A xx = #C3, required self::B yy = #C3}) → self::C
+  return new self::C::•();
+static method f5(core::int i, self::A b, core::Map<core::Object, core::Object> m, dynamic x, {required dynamic ox = #C3, required self::B ob = #C3, required core::List<dynamic> ol = #C3, required dynamic obool = #C3}) → self::C
+  return new self::C::•();
+static method main() → dynamic {
+  self::expect(true, #C1);
+  self::expect(#C5 is{ForNonNullableByDefault} ({required i: core::int}) → core::int, #C1);
+  self::expect(!self::inStrongMode, #C1);
+  self::expect(#C5 is{ForNonNullableByDefault} ({i: core::int}) → core::int, #C1);
+  self::expect(true, #C1);
+  self::expect(#C6 is{ForNonNullableByDefault} ({required i: core::int}) → core::int, #C1);
+  self::expect(true, #C1);
+  self::expect(#C6 is{ForNonNullableByDefault} ({i: core::int}) → core::int, #C1);
+  self::expect(false, #C2);
+  self::expect(#C5 is{ForNonNullableByDefault} ({required i1: core::int, required i10: core::int, required i11: core::int, required i12: core::int, required i13: core::int, required i14: core::int, required i15: core::int, required i16: core::int, required i17: core::int, required i18: core::int, required i19: core::int, required i2: core::int, required i20: core::int, required i21: core::int, required i22: core::int, required i23: core::int, required i24: core::int, required i25: core::int, required i26: core::int, required i27: core::int, required i28: core::int, required i29: core::int, required i3: core::int, required i30: core::int, required i31: core::int, required i32: core::int, required i33: core::int, required i34: core::int, required i35: core::int, required i36: core::int, required i37: core::int, required i38: core::int, required i39: core::int, required i4: core::int, required i40: core::int, required i41: core::int, required i42: core::int, required i43: core::int, required i44: core::int, required i45: core::int, required i46: core::int, required i47: core::int, required i48: core::int, required i49: core::int, required i5: core::int, required i50: core::int, required i51: core::int, required i52: core::int, required i53: core::int, required i54: core::int, required i55: core::int, required i56: core::int, required i57: core::int, required i58: core::int, required i59: core::int, required i6: core::int, required i60: core::int, required i61: core::int, required i62: core::int, required i63: core::int, required i64: core::int, required i65: core::int, required i66: core::int, required i67: core::int, required i68: core::int, required i69: core::int, required i7: core::int, required i70: core::int, required i8: core::int, required i9: core::int}) → core::int, #C2);
+  self::expect(false, #C2);
+  self::expect(#C7 is{ForNonNullableByDefault} (core::int, self::B, core::Map<core::int, core::num>, dynamic, {required ob: self::B, required obool: core::bool, required ol: core::List<core::num>, required ox: dynamic}) → self::B, #C2);
+  self::expect(false, #C2);
+  self::expect(#C8 is{ForNonNullableByDefault} (core::int, self::B, core::Map<core::int, core::num>, dynamic, {required ob: self::B, required obool: core::bool, required ol: core::List<core::num>, required ox: dynamic}) → self::B, #C2);
+  self::expect(!self::inStrongMode, #C1);
+  self::expect(#C9 is{ForNonNullableByDefault} (core::int, self::B, core::Map<core::int, core::num>, dynamic, {required ob: self::B, required obool: core::bool, required ol: core::List<core::num>, required ox: dynamic}) → self::B, #C1);
+  self::expect(!self::inStrongMode, #C1);
+  self::expect(#C10 is{ForNonNullableByDefault} (core::int, self::B, core::Map<core::int, core::num>, dynamic, {required ob: self::B, required obool: core::bool, required ol: core::List<core::num>, required ox: dynamic}) → self::B, #C1);
+  self::expect(true, #C1);
+  self::expect(#C11 is{ForNonNullableByDefault} (core::int, self::B, core::Map<core::int, core::num>, dynamic, {required ob: self::B, required obool: core::bool, required ol: core::List<core::num>, required ox: dynamic}) → self::B, #C1);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = true
+  #C2 = false
+  #C3 = null
+  #C4 = 1
+  #C5 = static-tearoff self::f
+  #C6 = static-tearoff self::g
+  #C7 = static-tearoff self::f1
+  #C8 = static-tearoff self::f2
+  #C9 = static-tearoff self::f3
+  #C10 = static-tearoff self::f4
+  #C11 = static-tearoff self::f5
+}
diff --git a/pkg/front_end/testcases/nnbd/constant_null_check.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/constant_null_check.dart.weak.modular.expect
new file mode 100644
index 0000000..a50f6c7
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/constant_null_check.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/constant_null_check.dart:9:17: Error: Constant evaluation error:
+// const int? d = c!;
+//                 ^
+// pkg/front_end/testcases/nnbd/constant_null_check.dart:9:17: Context: Constant expression must be non-null.
+// const int? d = c!;
+//                 ^
+// pkg/front_end/testcases/nnbd/constant_null_check.dart:9:12: Context: While analyzing:
+// const int? d = c!;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/constant_null_check.dart:17:23: Error: Constant evaluation error:
+// const Class f = const Class(c);
+//                       ^
+// pkg/front_end/testcases/nnbd/constant_null_check.dart:13:30: Context: Constant expression must be non-null.
+//   const Class(int? x) : y = x!;
+//                              ^
+// pkg/front_end/testcases/nnbd/constant_null_check.dart:17:13: Context: While analyzing:
+// const Class f = const Class(c);
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object /*hasConstConstructor*/  {
+  final field core::int y;
+  const constructor •(core::int? x) → self::Class
+    : self::Class::y = x!, super core::Object::•()
+    ;
+}
+static const field core::int? a = #C1;
+static const field core::int b = #C1;
+static const field core::int? c = #C2;
+static const field core::int? d = invalid-expression "Constant expression must be non-null.";
+static const field self::Class e = #C3;
+static const field self::Class f = invalid-expression "Constant expression must be non-null.";
+static method main() → dynamic {
+  self::expect(42, #C1);
+  self::expect(42, #C1);
+  self::expect(42, #C3.{self::Class::y}{core::int});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = 42
+  #C2 = null
+  #C3 = self::Class {y:#C1}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///constant_null_check.dart:
+- Class. (from org-dartlang-testcase:///constant_null_check.dart:13:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/constant_null_is.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/constant_null_is.dart.weak.modular.expect
new file mode 100644
index 0000000..94f3fa4
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/constant_null_is.dart.weak.modular.expect
@@ -0,0 +1,103 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+class Class<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field core::bool field;
+  const constructor constructor1(dynamic value) → self::Class<self::Class::T%>
+    : self::Class::field = value is{ForNonNullableByDefault} self::Class::T%, super core::Object::•()
+    ;
+  const constructor constructor2(dynamic value) → self::Class<self::Class::T%>
+    : self::Class::field = value is{ForNonNullableByDefault} self::Class::T?, super core::Object::•()
+    ;
+  const constructor constructor3(dynamic value) → self::Class<self::Class::T%>
+    : self::Class::field = value is{ForNonNullableByDefault} self::Class<self::Class::T%>, super core::Object::•()
+    ;
+  const constructor constructor4(dynamic value) → self::Class<self::Class::T%>
+    : self::Class::field = value is{ForNonNullableByDefault} self::Class<self::Class::T%>?, super core::Object::•()
+    ;
+}
+static final field core::bool isWeakMode = #C1 is{ForNonNullableByDefault} core::List<core::Object>;
+static const field core::bool c0 = #C2;
+static const field core::bool c1 = #C3;
+static const field core::bool c2 = #C2;
+static const field core::bool c3 = #C2;
+static const field core::bool c4 = #C3;
+static const field core::bool c5 = #C2;
+static const field core::bool c6 = #C3;
+static const field core::bool c7 = #C2;
+static const field core::bool c8 = #C2;
+static const field core::bool c9 = #C2;
+static const field core::bool c10 = #C3;
+static const field core::bool c11 = #C2;
+static const field core::bool c12 = #C2;
+static const field self::Class<core::int> e1 = #C4;
+static const field self::Class<core::List<core::int>> e2 = #C5;
+static const field self::Class<Null> e3 = #C6;
+static const field self::Class<core::int> e4 = #C7;
+static const field self::Class<core::int?> e5 = #C8;
+static const field self::Class<Null> e6 = #C6;
+static const field self::Class<core::int> e7 = #C4;
+static const field self::Class<core::int?> e8 = #C9;
+static const field self::Class<Null> e9 = #C10;
+static const field self::Class<core::int> e10 = #C7;
+static const field self::Class<core::int?> e11 = #C8;
+static const field self::Class<Null> e12 = #C6;
+static method main() → dynamic {
+  self::expect(null is{ForNonNullableByDefault} core::int?, #C2, "null is int?");
+  self::expect(null is{ForNonNullableByDefault} core::int, #C3, "null is int");
+  self::expect(null is{ForNonNullableByDefault} Null, #C2, "null is Null");
+  self::expect(null is{ForNonNullableByDefault} Never?, #C2, "null is Never?");
+  self::expect(null is{ForNonNullableByDefault} Never, #C3, "null is Never");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<core::int?>, #C2, "null is FutureOr<int?>");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<core::int>, #C3, "null is FutureOr<int>");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<core::int>?, #C2, "null is FutureOr<int>?");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<Null>, #C2, "null is FutureOr<Null>");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<Null>?, #C2, "null is FutureOr<Null>?");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<Never>, #C3, "null is FutureOr<Never>");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<Never?>, #C2, "null is FutureOr<Never?>");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<Never>?, #C2, "null is FutureOr<Never>?");
+  self::expect(new self::Class::constructor1<core::int>(null).{self::Class::field}{core::bool}, #C4.{self::Class::field}{core::bool}, "Class<int>.constructor1(null).field");
+  self::expect(true, new self::Class::constructor1<core::int?>(null).{self::Class::field}{core::bool}, "new Class<int?>.constructor1(null).field");
+  self::expect(self::isWeakMode, #C5.{self::Class::field}{core::bool}, "const Class<List<int>>.constructor1(<Null>[null]).field");
+  self::expect(new self::Class::constructor1<Null>(null).{self::Class::field}{core::bool}, #C6.{self::Class::field}{core::bool}, "Class<Null>.constructor1(null).field");
+  self::expect(new self::Class::constructor2<core::int>(null).{self::Class::field}{core::bool}, #C7.{self::Class::field}{core::bool}, "Class<int>.constructor2(null).field");
+  self::expect(true, new self::Class::constructor2<core::int?>(null).{self::Class::field}{core::bool}, "new Class<int?>.constructor2(null).field");
+  self::expect(new self::Class::constructor2<core::int?>(null).{self::Class::field}{core::bool}, #C8.{self::Class::field}{core::bool}, "Class<int?>.constructor2(null).field");
+  self::expect(new self::Class::constructor2<Null>(null).{self::Class::field}{core::bool}, #C6.{self::Class::field}{core::bool}, "Class<Null>.constructor2(null).field");
+  self::expect(new self::Class::constructor3<core::int>(null).{self::Class::field}{core::bool}, #C4.{self::Class::field}{core::bool}, "Class<int>.constructor3(null).field");
+  self::expect(new self::Class::constructor3<core::int?>(null).{self::Class::field}{core::bool}, #C9.{self::Class::field}{core::bool}, "Class<int?>.constructor3(null).field");
+  self::expect(new self::Class::constructor3<core::int?>(null).{self::Class::field}{core::bool}, #C9.{self::Class::field}{core::bool}, "Class<int?>.constructor3(null).field");
+  self::expect(new self::Class::constructor3<Null>(null).{self::Class::field}{core::bool}, #C10.{self::Class::field}{core::bool}, "Class<Null>.constructor3(null).field");
+  self::expect(new self::Class::constructor4<core::int>(null).{self::Class::field}{core::bool}, #C7.{self::Class::field}{core::bool}, "Class<int>.constructor4(null).field");
+  self::expect(new self::Class::constructor4<core::int?>(null).{self::Class::field}{core::bool}, #C8.{self::Class::field}{core::bool}, "Class<int?>.constructor4(null).field");
+  self::expect(new self::Class::constructor4<Null>(null).{self::Class::field}{core::bool}, #C6.{self::Class::field}{core::bool}, "Class<Null>.constructor4(null).field");
+}
+static method expect(dynamic expected, dynamic actual, core::String message) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual} for ${message}";
+}
+
+constants  {
+  #C1 = <Null>[]
+  #C2 = true
+  #C3 = false
+  #C4 = self::Class<core::int*> {field:#C3}
+  #C5 = self::Class<core::List<core::int*>*> {field:#C2}
+  #C6 = self::Class<Null> {field:#C2}
+  #C7 = self::Class<core::int*> {field:#C2}
+  #C8 = self::Class<core::int?> {field:#C2}
+  #C9 = self::Class<core::int?> {field:#C3}
+  #C10 = self::Class<Null> {field:#C3}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///constant_null_is.dart:
+- Class.constructor1 (from org-dartlang-testcase:///constant_null_is.dart:38:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Class.constructor2 (from org-dartlang-testcase:///constant_null_is.dart:39:9)
+- Class.constructor3 (from org-dartlang-testcase:///constant_null_is.dart:40:9)
+- Class.constructor4 (from org-dartlang-testcase:///constant_null_is.dart:41:9)
diff --git a/pkg/front_end/testcases/nnbd/constants.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/constants.dart.weak.modular.expect
new file mode 100644
index 0000000..9af4cec
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/constants.dart.weak.modular.expect
@@ -0,0 +1,114 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "constants_lib.dart" as con;
+
+import "org-dartlang-testcase:///constants_lib.dart" as lib;
+
+typedef F1<invariant T extends core::Object? = dynamic> = (T%) → T%;
+typedef F2 = <T extends core::Object? = dynamic>(T%) → T%;
+static const field core::Type objectTypeLiteral = #C1;
+static const field (core::int) → core::int partialInstantiation = #C3;
+static const field con::Class<core::int> instance = #C5;
+static const field core::Type functionTypeLiteral = #C6;
+static const field core::Type genericFunctionTypeLiteral = #C7;
+static const field core::List<core::int> listLiteral = #C8;
+static const field core::Set<core::int> setLiteral = #C9;
+static const field core::Map<core::int, core::String> mapLiteral = #C11;
+static const field core::List<core::int> listConcatenation = #C8;
+static const field core::Set<core::int> setConcatenation = #C9;
+static const field core::Map<core::int, core::String> mapConcatenation = #C11;
+static const field core::bool objectTypeLiteralIdentical = #C12;
+static const field core::bool partialInstantiationIdentical = #C12;
+static const field core::bool instanceIdentical = #C12;
+static const field core::bool functionTypeLiteralIdentical = #C12;
+static const field core::bool genericFunctionTypeLiteralIdentical = #C12;
+static const field core::bool listLiteralIdentical = #C12;
+static const field core::bool setLiteralIdentical = #C12;
+static const field core::bool mapLiteralIdentical = #C12;
+static const field core::bool listConcatenationIdentical = #C12;
+static const field core::bool setConcatenationIdentical = #C12;
+static const field core::bool mapConcatenationIdentical = #C12;
+static method main() → dynamic {
+  self::test(#C1, #C1);
+  self::test(#C3, #C3);
+  self::test(#C5, #C5);
+  self::test(#C6, #C6);
+  self::test(#C7, #C7);
+  self::test(#C8, #C8);
+  self::test(#C9, #C9);
+  self::test(#C11, #C11);
+  self::test(#C8, #C8);
+  self::test(#C9, #C9);
+  self::test(#C11, #C11);
+  self::test(true, #C12);
+  self::test(true, #C12);
+  self::test(true, #C12);
+  self::test(true, #C12);
+  self::test(true, #C12);
+  self::test(true, #C12);
+  self::test(true, #C12);
+  self::test(true, #C12);
+  self::test(true, #C12);
+  self::test(true, #C12);
+  self::test(true, #C12);
+}
+static method test(dynamic expected, dynamic actual) → dynamic {
+  core::print("test(${expected}, ${actual})");
+  if(!core::identical(expected, actual)) {
+    throw "Expected ${expected}, actual ${actual}";
+  }
+}
+
+library /*isNonNullableByDefault*/;
+import self as con;
+import "dart:core" as core;
+
+typedef F1<invariant T extends core::Object? = dynamic> = (T%) → T%;
+typedef F2 = <T extends core::Object? = dynamic>(T%) → T%;
+class Class<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field con::Class::T% field;
+  const constructor •(con::Class::T% field) → con::Class<con::Class::T%>
+    : con::Class::field = field, super core::Object::•()
+    ;
+}
+static const field core::Type objectTypeLiteral = #C1;
+static const field (core::Object?, core::Object?) → core::bool c2 = #C13;
+static const field (core::int) → core::int partialInstantiation = #C3;
+static const field con::Class<core::int> instance = #C5;
+static const field core::Type functionTypeLiteral = #C6;
+static const field core::Type genericFunctionTypeLiteral = #C7;
+static const field core::List<core::int> listLiteral = #C8;
+static const field core::Set<core::int> setLiteral = #C9;
+static const field core::Map<core::int, core::String> mapLiteral = #C11;
+static const field core::List<core::int> listConcatenation = #C8;
+static const field core::Set<core::int> setConcatenation = #C9;
+static const field core::Map<core::int, core::String> mapConcatenation = #C11;
+static method id<T extends core::Object? = dynamic>(con::id::T% t) → con::id::T%
+  return t;
+
+constants  {
+  #C1 = TypeLiteralConstant(core::Object*)
+  #C2 = static-tearoff con::id
+  #C3 = instantiation #C2 <core::int*>
+  #C4 = 0
+  #C5 = con::Class<core::int*> {field:#C4}
+  #C6 = TypeLiteralConstant((dynamic) →* dynamic)
+  #C7 = TypeLiteralConstant(<T extends core::Object? = dynamic>(T*) →* T*)
+  #C8 = <core::int*>[#C4]
+  #C9 = <core::int*>{#C4}
+  #C10 = "foo"
+  #C11 = <core::int*, core::String*>{#C4:#C10)
+  #C12 = true
+  #C13 = static-tearoff core::identical
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///constants.dart:
+- Class. (from org-dartlang-testcase:///constants_lib.dart:8:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+
+org-dartlang-testcase:///constants_lib.dart:
+- Class. (from org-dartlang-testcase:///constants_lib.dart:8:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/covariant_equals.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/covariant_equals.dart.weak.modular.expect
new file mode 100644
index 0000000..ac2d469
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/covariant_equals.dart.weak.modular.expect
@@ -0,0 +1,546 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:24:8: Error: The argument type 'C<dynamic>' can't be assigned to the parameter type 'A?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   a == c_dynamic; // error
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:25:8: Error: The argument type 'C<int>' can't be assigned to the parameter type 'A?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   a == c_int; // error
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:26:8: Error: The argument type 'C<String>' can't be assigned to the parameter type 'A?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   a == c_string; // error
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:27:8: Error: The argument type 'D' can't be assigned to the parameter type 'A?'.
+//  - 'D' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   a == d; // error
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:31:8: Error: The argument type 'C<dynamic>' can't be assigned to the parameter type 'A?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   b == c_dynamic; // error
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:32:8: Error: The argument type 'C<int>' can't be assigned to the parameter type 'A?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   b == c_int; // error
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:33:8: Error: The argument type 'C<String>' can't be assigned to the parameter type 'A?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   b == c_string; // error
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:34:8: Error: The argument type 'D' can't be assigned to the parameter type 'A?'.
+//  - 'D' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   b == d; // error
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:36:16: Error: The argument type 'A' can't be assigned to the parameter type 'C<dynamic>?'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_dynamic == a; // error
+//                ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:37:16: Error: The argument type 'B' can't be assigned to the parameter type 'C<dynamic>?'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_dynamic == b; // error
+//                ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:43:12: Error: The argument type 'A' can't be assigned to the parameter type 'C<int>?'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_int == a; // error
+//            ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:44:12: Error: The argument type 'B' can't be assigned to the parameter type 'C<int>?'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_int == b; // error
+//            ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:45:12: Error: The argument type 'C<dynamic>' can't be assigned to the parameter type 'C<int>?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_int == c_dynamic; // error
+//            ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:47:12: Error: The argument type 'C<String>' can't be assigned to the parameter type 'C<int>?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_int == c_string; // error
+//            ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:50:15: Error: The argument type 'A' can't be assigned to the parameter type 'C<String>?'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_string == a; // error
+//               ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:51:15: Error: The argument type 'B' can't be assigned to the parameter type 'C<String>?'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_string == b; // error
+//               ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:52:15: Error: The argument type 'C<dynamic>' can't be assigned to the parameter type 'C<String>?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_string == c_dynamic; // error
+//               ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:53:15: Error: The argument type 'C<int>' can't be assigned to the parameter type 'C<String>?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_string == c_int; // error
+//               ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:55:15: Error: The argument type 'D' can't be assigned to the parameter type 'C<String>?'.
+//  - 'D' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_string == d; // error
+//               ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:57:8: Error: The argument type 'A' can't be assigned to the parameter type 'C<int>?'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   d == a; // error
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:58:8: Error: The argument type 'B' can't be assigned to the parameter type 'C<int>?'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   d == b; // error
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:59:8: Error: The argument type 'C<dynamic>' can't be assigned to the parameter type 'C<int>?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   d == c_dynamic; // error
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:61:8: Error: The argument type 'C<String>' can't be assigned to the parameter type 'C<int>?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   d == c_string; // error
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:75:8: Error: The argument type 'C<dynamic>?' can't be assigned to the parameter type 'A?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   a == c_dynamic; // ok or error ?
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:76:8: Error: The argument type 'C<int>?' can't be assigned to the parameter type 'A?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   a == c_int; // ok or error ?
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:77:8: Error: The argument type 'C<String>?' can't be assigned to the parameter type 'A?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   a == c_string; // ok or error ?
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:78:8: Error: The argument type 'D?' can't be assigned to the parameter type 'A?'.
+//  - 'D' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   a == d; // ok or error ?
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:82:8: Error: The argument type 'C<dynamic>?' can't be assigned to the parameter type 'A?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   b == c_dynamic; // ok or error ?
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:83:8: Error: The argument type 'C<int>?' can't be assigned to the parameter type 'A?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   b == c_int; // ok or error ?
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:84:8: Error: The argument type 'C<String>?' can't be assigned to the parameter type 'A?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   b == c_string; // ok or error ?
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:85:8: Error: The argument type 'D?' can't be assigned to the parameter type 'A?'.
+//  - 'D' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   b == d; // ok or error ?
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:87:16: Error: The argument type 'A?' can't be assigned to the parameter type 'C<dynamic>?'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_dynamic == a; // ok or error ?
+//                ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:88:16: Error: The argument type 'B?' can't be assigned to the parameter type 'C<dynamic>?'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_dynamic == b; // ok or error ?
+//                ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:94:12: Error: The argument type 'A?' can't be assigned to the parameter type 'C<int>?'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_int == a; // ok or error ?
+//            ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:95:12: Error: The argument type 'B?' can't be assigned to the parameter type 'C<int>?'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_int == b; // ok or error ?
+//            ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:96:12: Error: The argument type 'C<dynamic>?' can't be assigned to the parameter type 'C<int>?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_int == c_dynamic; // ok or error ?
+//            ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:98:12: Error: The argument type 'C<String>?' can't be assigned to the parameter type 'C<int>?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_int == c_string; // ok or error ?
+//            ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:101:15: Error: The argument type 'A?' can't be assigned to the parameter type 'C<String>?'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_string == a; // ok or error ?
+//               ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:102:15: Error: The argument type 'B?' can't be assigned to the parameter type 'C<String>?'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_string == b; // ok or error ?
+//               ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:103:15: Error: The argument type 'C<dynamic>?' can't be assigned to the parameter type 'C<String>?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_string == c_dynamic; // ok or error ?
+//               ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:104:15: Error: The argument type 'C<int>?' can't be assigned to the parameter type 'C<String>?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_string == c_int; // ok or error ?
+//               ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:106:15: Error: The argument type 'D?' can't be assigned to the parameter type 'C<String>?'.
+//  - 'D' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   c_string == d; // ok or error ?
+//               ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:108:8: Error: The argument type 'A?' can't be assigned to the parameter type 'C<int>?'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   d == a; // ok or error ?
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:109:8: Error: The argument type 'B?' can't be assigned to the parameter type 'C<int>?'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   d == b; // ok or error ?
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:110:8: Error: The argument type 'C<dynamic>?' can't be assigned to the parameter type 'C<int>?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   d == c_dynamic; // ok or error ?
+//        ^
+//
+// pkg/front_end/testcases/nnbd/covariant_equals.dart:112:8: Error: The argument type 'C<String>?' can't be assigned to the parameter type 'C<int>?'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+//   d == c_string; // ok or error ?
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  operator ==(covariant-by-declaration self::A other) → core::bool
+    return true;
+}
+class B extends self::A {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+  operator ==(covariant-by-declaration self::A other) → core::bool
+    return true;
+}
+class C<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T%>
+    : super core::Object::•()
+    ;
+  operator ==(covariant-by-declaration covariant-by-class self::C<self::C::T%> other) → core::bool
+    return true;
+}
+class D extends self::C<core::int> {
+  synthetic constructor •() → self::D
+    : super self::C::•()
+    ;
+}
+static method main() → dynamic {}
+static method testNonNullable(self::A a, self::B b, self::C<dynamic> c_dynamic, self::C<core::int> c_int, self::C<core::String> c_string, self::D d) → dynamic {
+  a =={self::A::==}{(self::A) → core::bool} a;
+  a =={self::A::==}{(self::A) → core::bool} b;
+  a =={self::A::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:24:8: Error: The argument type 'C<dynamic>' can't be assigned to the parameter type 'A?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  a == c_dynamic; // error
+       ^" in c_dynamic as{TypeError,ForNonNullableByDefault} self::A?;
+  a =={self::A::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:25:8: Error: The argument type 'C<int>' can't be assigned to the parameter type 'A?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  a == c_int; // error
+       ^" in c_int as{TypeError,ForNonNullableByDefault} self::A?;
+  a =={self::A::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:26:8: Error: The argument type 'C<String>' can't be assigned to the parameter type 'A?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  a == c_string; // error
+       ^" in c_string as{TypeError,ForNonNullableByDefault} self::A?;
+  a =={self::A::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:27:8: Error: The argument type 'D' can't be assigned to the parameter type 'A?'.
+ - 'D' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  a == d; // error
+       ^" in d as{TypeError,ForNonNullableByDefault} self::A?;
+  b =={self::B::==}{(self::A) → core::bool} a;
+  b =={self::B::==}{(self::A) → core::bool} b;
+  b =={self::B::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:31:8: Error: The argument type 'C<dynamic>' can't be assigned to the parameter type 'A?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  b == c_dynamic; // error
+       ^" in c_dynamic as{TypeError,ForNonNullableByDefault} self::A?;
+  b =={self::B::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:32:8: Error: The argument type 'C<int>' can't be assigned to the parameter type 'A?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  b == c_int; // error
+       ^" in c_int as{TypeError,ForNonNullableByDefault} self::A?;
+  b =={self::B::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:33:8: Error: The argument type 'C<String>' can't be assigned to the parameter type 'A?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  b == c_string; // error
+       ^" in c_string as{TypeError,ForNonNullableByDefault} self::A?;
+  b =={self::B::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:34:8: Error: The argument type 'D' can't be assigned to the parameter type 'A?'.
+ - 'D' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  b == d; // error
+       ^" in d as{TypeError,ForNonNullableByDefault} self::A?;
+  c_dynamic =={self::C::==}{(self::C<dynamic>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:36:16: Error: The argument type 'A' can't be assigned to the parameter type 'C<dynamic>?'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_dynamic == a; // error
+               ^" in a as{TypeError,ForNonNullableByDefault} self::C<dynamic>?;
+  c_dynamic =={self::C::==}{(self::C<dynamic>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:37:16: Error: The argument type 'B' can't be assigned to the parameter type 'C<dynamic>?'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_dynamic == b; // error
+               ^" in b as{TypeError,ForNonNullableByDefault} self::C<dynamic>?;
+  c_dynamic =={self::C::==}{(self::C<dynamic>) → core::bool} c_dynamic;
+  c_dynamic =={self::C::==}{(self::C<dynamic>) → core::bool} c_int;
+  c_dynamic =={self::C::==}{(self::C<dynamic>) → core::bool} c_string;
+  c_dynamic =={self::C::==}{(self::C<dynamic>) → core::bool} d;
+  c_int =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:43:12: Error: The argument type 'A' can't be assigned to the parameter type 'C<int>?'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_int == a; // error
+           ^" in a as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  c_int =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:44:12: Error: The argument type 'B' can't be assigned to the parameter type 'C<int>?'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_int == b; // error
+           ^" in b as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  c_int =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:45:12: Error: The argument type 'C<dynamic>' can't be assigned to the parameter type 'C<int>?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_int == c_dynamic; // error
+           ^" in c_dynamic as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  c_int =={self::C::==}{(self::C<core::int>) → core::bool} c_int;
+  c_int =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:47:12: Error: The argument type 'C<String>' can't be assigned to the parameter type 'C<int>?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_int == c_string; // error
+           ^" in c_string as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  c_int =={self::C::==}{(self::C<core::int>) → core::bool} d;
+  c_string =={self::C::==}{(self::C<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:50:15: Error: The argument type 'A' can't be assigned to the parameter type 'C<String>?'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_string == a; // error
+              ^" in a as{TypeError,ForNonNullableByDefault} self::C<core::String>?;
+  c_string =={self::C::==}{(self::C<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:51:15: Error: The argument type 'B' can't be assigned to the parameter type 'C<String>?'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_string == b; // error
+              ^" in b as{TypeError,ForNonNullableByDefault} self::C<core::String>?;
+  c_string =={self::C::==}{(self::C<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:52:15: Error: The argument type 'C<dynamic>' can't be assigned to the parameter type 'C<String>?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_string == c_dynamic; // error
+              ^" in c_dynamic as{TypeError,ForNonNullableByDefault} self::C<core::String>?;
+  c_string =={self::C::==}{(self::C<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:53:15: Error: The argument type 'C<int>' can't be assigned to the parameter type 'C<String>?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_string == c_int; // error
+              ^" in c_int as{TypeError,ForNonNullableByDefault} self::C<core::String>?;
+  c_string =={self::C::==}{(self::C<core::String>) → core::bool} c_string;
+  c_string =={self::C::==}{(self::C<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:55:15: Error: The argument type 'D' can't be assigned to the parameter type 'C<String>?'.
+ - 'D' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_string == d; // error
+              ^" in d as{TypeError,ForNonNullableByDefault} self::C<core::String>?;
+  d =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:57:8: Error: The argument type 'A' can't be assigned to the parameter type 'C<int>?'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  d == a; // error
+       ^" in a as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  d =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:58:8: Error: The argument type 'B' can't be assigned to the parameter type 'C<int>?'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  d == b; // error
+       ^" in b as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  d =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:59:8: Error: The argument type 'C<dynamic>' can't be assigned to the parameter type 'C<int>?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  d == c_dynamic; // error
+       ^" in c_dynamic as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  d =={self::C::==}{(self::C<core::int>) → core::bool} c_int;
+  d =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:61:8: Error: The argument type 'C<String>' can't be assigned to the parameter type 'C<int>?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  d == c_string; // error
+       ^" in c_string as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  d =={self::C::==}{(self::C<core::int>) → core::bool} d;
+}
+static method testNullable(self::A? a, self::B? b, self::C<dynamic>? c_dynamic, self::C<core::int>? c_int, self::C<core::String>? c_string, self::D? d) → dynamic {
+  a =={self::A::==}{(self::A) → core::bool} a;
+  a =={self::A::==}{(self::A) → core::bool} b;
+  a =={self::A::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:75:8: Error: The argument type 'C<dynamic>?' can't be assigned to the parameter type 'A?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  a == c_dynamic; // ok or error ?
+       ^" in c_dynamic as{TypeError,ForNonNullableByDefault} self::A?;
+  a =={self::A::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:76:8: Error: The argument type 'C<int>?' can't be assigned to the parameter type 'A?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  a == c_int; // ok or error ?
+       ^" in c_int as{TypeError,ForNonNullableByDefault} self::A?;
+  a =={self::A::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:77:8: Error: The argument type 'C<String>?' can't be assigned to the parameter type 'A?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  a == c_string; // ok or error ?
+       ^" in c_string as{TypeError,ForNonNullableByDefault} self::A?;
+  a =={self::A::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:78:8: Error: The argument type 'D?' can't be assigned to the parameter type 'A?'.
+ - 'D' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  a == d; // ok or error ?
+       ^" in d as{TypeError,ForNonNullableByDefault} self::A?;
+  b =={self::B::==}{(self::A) → core::bool} a;
+  b =={self::B::==}{(self::A) → core::bool} b;
+  b =={self::B::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:82:8: Error: The argument type 'C<dynamic>?' can't be assigned to the parameter type 'A?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  b == c_dynamic; // ok or error ?
+       ^" in c_dynamic as{TypeError,ForNonNullableByDefault} self::A?;
+  b =={self::B::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:83:8: Error: The argument type 'C<int>?' can't be assigned to the parameter type 'A?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  b == c_int; // ok or error ?
+       ^" in c_int as{TypeError,ForNonNullableByDefault} self::A?;
+  b =={self::B::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:84:8: Error: The argument type 'C<String>?' can't be assigned to the parameter type 'A?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  b == c_string; // ok or error ?
+       ^" in c_string as{TypeError,ForNonNullableByDefault} self::A?;
+  b =={self::B::==}{(self::A) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:85:8: Error: The argument type 'D?' can't be assigned to the parameter type 'A?'.
+ - 'D' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  b == d; // ok or error ?
+       ^" in d as{TypeError,ForNonNullableByDefault} self::A?;
+  c_dynamic =={self::C::==}{(self::C<dynamic>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:87:16: Error: The argument type 'A?' can't be assigned to the parameter type 'C<dynamic>?'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_dynamic == a; // ok or error ?
+               ^" in a as{TypeError,ForNonNullableByDefault} self::C<dynamic>?;
+  c_dynamic =={self::C::==}{(self::C<dynamic>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:88:16: Error: The argument type 'B?' can't be assigned to the parameter type 'C<dynamic>?'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_dynamic == b; // ok or error ?
+               ^" in b as{TypeError,ForNonNullableByDefault} self::C<dynamic>?;
+  c_dynamic =={self::C::==}{(self::C<dynamic>) → core::bool} c_dynamic;
+  c_dynamic =={self::C::==}{(self::C<dynamic>) → core::bool} c_int;
+  c_dynamic =={self::C::==}{(self::C<dynamic>) → core::bool} c_string;
+  c_dynamic =={self::C::==}{(self::C<dynamic>) → core::bool} d;
+  c_int =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:94:12: Error: The argument type 'A?' can't be assigned to the parameter type 'C<int>?'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_int == a; // ok or error ?
+           ^" in a as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  c_int =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:95:12: Error: The argument type 'B?' can't be assigned to the parameter type 'C<int>?'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_int == b; // ok or error ?
+           ^" in b as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  c_int =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:96:12: Error: The argument type 'C<dynamic>?' can't be assigned to the parameter type 'C<int>?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_int == c_dynamic; // ok or error ?
+           ^" in c_dynamic as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  c_int =={self::C::==}{(self::C<core::int>) → core::bool} c_int;
+  c_int =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:98:12: Error: The argument type 'C<String>?' can't be assigned to the parameter type 'C<int>?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_int == c_string; // ok or error ?
+           ^" in c_string as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  c_int =={self::C::==}{(self::C<core::int>) → core::bool} d;
+  c_string =={self::C::==}{(self::C<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:101:15: Error: The argument type 'A?' can't be assigned to the parameter type 'C<String>?'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_string == a; // ok or error ?
+              ^" in a as{TypeError,ForNonNullableByDefault} self::C<core::String>?;
+  c_string =={self::C::==}{(self::C<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:102:15: Error: The argument type 'B?' can't be assigned to the parameter type 'C<String>?'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_string == b; // ok or error ?
+              ^" in b as{TypeError,ForNonNullableByDefault} self::C<core::String>?;
+  c_string =={self::C::==}{(self::C<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:103:15: Error: The argument type 'C<dynamic>?' can't be assigned to the parameter type 'C<String>?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_string == c_dynamic; // ok or error ?
+              ^" in c_dynamic as{TypeError,ForNonNullableByDefault} self::C<core::String>?;
+  c_string =={self::C::==}{(self::C<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:104:15: Error: The argument type 'C<int>?' can't be assigned to the parameter type 'C<String>?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_string == c_int; // ok or error ?
+              ^" in c_int as{TypeError,ForNonNullableByDefault} self::C<core::String>?;
+  c_string =={self::C::==}{(self::C<core::String>) → core::bool} c_string;
+  c_string =={self::C::==}{(self::C<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:106:15: Error: The argument type 'D?' can't be assigned to the parameter type 'C<String>?'.
+ - 'D' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  c_string == d; // ok or error ?
+              ^" in d as{TypeError,ForNonNullableByDefault} self::C<core::String>?;
+  d =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:108:8: Error: The argument type 'A?' can't be assigned to the parameter type 'C<int>?'.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  d == a; // ok or error ?
+       ^" in a as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  d =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:109:8: Error: The argument type 'B?' can't be assigned to the parameter type 'C<int>?'.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  d == b; // ok or error ?
+       ^" in b as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  d =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:110:8: Error: The argument type 'C<dynamic>?' can't be assigned to the parameter type 'C<int>?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  d == c_dynamic; // ok or error ?
+       ^" in c_dynamic as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  d =={self::C::==}{(self::C<core::int>) → core::bool} c_int;
+  d =={self::C::==}{(self::C<core::int>) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/covariant_equals.dart:112:8: Error: The argument type 'C<String>?' can't be assigned to the parameter type 'C<int>?'.
+ - 'C' is from 'pkg/front_end/testcases/nnbd/covariant_equals.dart'.
+  d == c_string; // ok or error ?
+       ^" in c_string as{TypeError,ForNonNullableByDefault} self::C<core::int>?;
+  d =={self::C::==}{(self::C<core::int>) → core::bool} d;
+}
diff --git a/pkg/front_end/testcases/nnbd/covariant_late_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/covariant_late_field.dart.weak.modular.expect
new file mode 100644
index 0000000..2aecfe1
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/covariant_late_field.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/covariant_late_field.dart:19:31: Error: The parameter 'value' of the method 'C.invariantField' has type 'int', which does not match the corresponding type, 'num', in the overridden method, 'A.invariantField'.
+// Change to a supertype of 'num', or, for a covariant parameter, a subtype.
+//   void set invariantField(int value) {} // error
+//                               ^
+// pkg/front_end/testcases/nnbd/covariant_late_field.dart:6:12: Context: This is the overridden method ('invariantField').
+//   late num invariantField;
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  late field core::num invariantField;
+  late covariant-by-declaration field core::num covariantField;
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+abstract class B extends core::Object implements self::A {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+  abstract get invariantField() → core::num;
+  abstract set invariantField(core::num value) → void;
+  abstract get covariantField() → core::num;
+  abstract set covariantField(covariant-by-declaration core::num value) → void;
+}
+abstract class C extends core::Object implements self::A {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  abstract get invariantField() → core::int;
+  set invariantField(core::int value) → void {}
+  abstract get covariantField() → core::int;
+  set covariantField(covariant-by-declaration core::int value) → void {}
+}
+abstract class D extends core::Object implements self::A {
+  synthetic constructor •() → self::D
+    : super core::Object::•()
+    ;
+  abstract get invariantField() → core::int;
+  set invariantField(covariant-by-declaration core::int value) → void {}
+  abstract get covariantField() → core::int;
+  set covariantField(covariant-by-declaration core::int value) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/covariant_nnbd_top_merge.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/covariant_nnbd_top_merge.dart.weak.modular.expect
new file mode 100644
index 0000000..692e181
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/covariant_nnbd_top_merge.dart.weak.modular.expect
@@ -0,0 +1,76 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  abstract method method(dynamic a) → void;
+}
+abstract class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+  abstract method method(covariant-by-declaration core::num a) → void;
+}
+abstract class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  abstract method method(covariant-by-declaration core::int a) → void;
+}
+abstract class D1 extends core::Object implements self::A, self::B, self::C {
+  synthetic constructor •() → self::D1
+    : super core::Object::•()
+    ;
+  abstract forwarding-stub method method(covariant-by-declaration dynamic a) → void;
+}
+abstract class D2 extends core::Object implements self::A, self::B {
+  synthetic constructor •() → self::D2
+    : super core::Object::•()
+    ;
+  abstract forwarding-stub method method(covariant-by-declaration dynamic a) → void;
+}
+abstract class D3 extends core::Object implements self::B, self::C {
+  synthetic constructor •() → self::D3
+    : super core::Object::•()
+    ;
+}
+abstract class D4 extends core::Object implements self::C, self::B {
+  synthetic constructor •() → self::D4
+    : super core::Object::•()
+    ;
+  abstract member-signature method method(covariant-by-declaration core::num a) → void; -> self::B::method
+}
+abstract class D5 extends core::Object implements self::A, self::C {
+  synthetic constructor •() → self::D5
+    : super core::Object::•()
+    ;
+  abstract forwarding-stub method method(covariant-by-declaration dynamic a) → void;
+}
+abstract class E extends core::Object {
+  synthetic constructor •() → self::E
+    : super core::Object::•()
+    ;
+  abstract method method(core::num a) → void;
+}
+abstract class F extends core::Object {
+  synthetic constructor •() → self::F
+    : super core::Object::•()
+    ;
+  abstract method method(covariant-by-declaration core::int a) → void;
+}
+abstract class G1 extends core::Object implements self::E, self::F {
+  synthetic constructor •() → self::G1
+    : super core::Object::•()
+    ;
+  abstract forwarding-stub method method(covariant-by-declaration core::num a) → void;
+}
+abstract class G2 extends core::Object implements self::F, self::E {
+  synthetic constructor •() → self::G2
+    : super core::Object::•()
+    ;
+  abstract forwarding-stub method method(covariant-by-declaration core::num a) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/definite_assignment_and_completion.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/definite_assignment_and_completion.dart.weak.modular.expect
new file mode 100644
index 0000000..aae820c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/definite_assignment_and_completion.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/definite_assignment_and_completion.dart:10:10: Error: Non-nullable variable 'x' must be assigned before it can be used.
+//   return x;
+//          ^
+//
+// pkg/front_end/testcases/nnbd/definite_assignment_and_completion.dart:28:12: Error: Non-nullable variable 'x' must be assigned before it can be used.
+//     return x;
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object /*hasConstConstructor*/  {
+  final field core::int x;
+  const constructor •(core::int x) → self::Class
+    : self::Class::x = x, super core::Object::•()
+    ;
+  method foo() → core::int {
+    core::int x;
+    return invalid-expression "pkg/front_end/testcases/nnbd/definite_assignment_and_completion.dart:28:12: Error: Non-nullable variable 'x' must be assigned before it can be used.
+    return x;
+           ^" in x;
+  }
+  method bar() → core::int
+    return 0;
+  method baz(core::int x) → core::int {
+    return x;
+  }
+  method boz(core::int x) → core::int
+    return x;
+}
+static method foo() → core::int {
+  core::int x;
+  return invalid-expression "pkg/front_end/testcases/nnbd/definite_assignment_and_completion.dart:10:10: Error: Non-nullable variable 'x' must be assigned before it can be used.
+  return x;
+         ^" in x;
+}
+static method bar() → core::int
+  return 0;
+static method baz(core::int x) → core::int {
+  return x;
+}
+static method boz(core::int x) → core::int
+  return x;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/definitely_assigned.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/definitely_assigned.dart.weak.modular.expect
new file mode 100644
index 0000000..8a0aaba
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/definitely_assigned.dart.weak.modular.expect
@@ -0,0 +1,158 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/definitely_assigned.dart:16:3: Error: Late final variable 'local2' definitely assigned.
+//   local2 = value; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_assigned.dart:17:3: Error: Late final variable 'local4' definitely assigned.
+//   local4 = 0; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_assigned.dart:18:3: Error: Late final variable 'local6' definitely assigned.
+//   local6 = 0; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_assigned.dart:30:3: Error: Late final variable 'local2' definitely assigned.
+//   local2 = value; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_assigned.dart:31:3: Error: Late final variable 'local4' definitely assigned.
+//   local4 = 0; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_assigned.dart:32:3: Error: Late final variable 'local6' definitely assigned.
+//   local6 = 0; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_assigned.dart:50:3: Error: Late final variable 'local2' definitely assigned.
+//   local2 = value; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_assigned.dart:51:3: Error: Late final variable 'local4' definitely assigned.
+//   local4 = 0; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_assigned.dart:52:3: Error: Late final variable 'local6' definitely assigned.
+//   local6 = 0; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_assigned.dart:70:3: Error: Late final variable 'local2' definitely assigned.
+//   local2 = value; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_assigned.dart:71:3: Error: Late final variable 'local4' definitely assigned.
+//   local4 = 0; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_assigned.dart:72:3: Error: Late final variable 'local6' definitely assigned.
+//   local6 = 0; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_assigned.dart:80:3: Error: Late final variable 'local4' definitely assigned.
+//   local4 += 0; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_assigned.dart:88:3: Error: Late final variable 'local4' definitely assigned.
+//   local4 += 0; // error
+//   ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+static field <T extends core::Object? = dynamic>(T%) → Null fieldDirect = <T extends core::Object? = dynamic>(T% value) → Null {
+  late final T% local2;
+  late final core::int local4;
+  late final FutureOr<core::int>local6;
+  local2 = value;
+  local4 = 0;
+  local6 = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_assigned.dart:30:3: Error: Late final variable 'local2' definitely assigned.
+  local2 = value; // error
+  ^^^^^^" in local2 = value;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_assigned.dart:31:3: Error: Late final variable 'local4' definitely assigned.
+  local4 = 0; // error
+  ^^^^^^" in local4 = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_assigned.dart:32:3: Error: Late final variable 'local6' definitely assigned.
+  local6 = 0; // error
+  ^^^^^^" in local6 = 0;
+};
+static field <T extends core::Object? = dynamic>(core::bool, T%) → Null fieldConditional = <T extends core::Object? = dynamic>(core::bool b, T% value) → Null {
+  late final T% local2;
+  late final core::int local4;
+  late final FutureOr<core::int>local6;
+  if(b) {
+    local2 = value;
+    local4 = 0;
+    local6 = 0;
+  }
+  local2 = value;
+  local4 = 0;
+  local6 = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_assigned.dart:70:3: Error: Late final variable 'local2' definitely assigned.
+  local2 = value; // error
+  ^^^^^^" in local2 = value;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_assigned.dart:71:3: Error: Late final variable 'local4' definitely assigned.
+  local4 = 0; // error
+  ^^^^^^" in local4 = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_assigned.dart:72:3: Error: Late final variable 'local6' definitely assigned.
+  local6 = 0; // error
+  ^^^^^^" in local6 = 0;
+};
+static field () → Null fieldCompound = () → Null {
+  late final core::int local4;
+  local4 = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_assigned.dart:88:3: Error: Late final variable 'local4' definitely assigned.
+  local4 += 0; // error
+  ^^^^^^" in local4 = local4.{core::num::+}(0){(core::num) → core::int};
+};
+static method methodDirect<T extends core::Object? = dynamic>(self::methodDirect::T% value) → dynamic {
+  late final self::methodDirect::T% local2;
+  late final core::int local4;
+  late final FutureOr<core::int>local6;
+  local2 = value;
+  local4 = 0;
+  local6 = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_assigned.dart:16:3: Error: Late final variable 'local2' definitely assigned.
+  local2 = value; // error
+  ^^^^^^" in local2 = value;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_assigned.dart:17:3: Error: Late final variable 'local4' definitely assigned.
+  local4 = 0; // error
+  ^^^^^^" in local4 = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_assigned.dart:18:3: Error: Late final variable 'local6' definitely assigned.
+  local6 = 0; // error
+  ^^^^^^" in local6 = 0;
+}
+static method methodConditional<T extends core::Object? = dynamic>(core::bool b, self::methodConditional::T% value) → dynamic {
+  late final self::methodConditional::T% local2;
+  late final core::int local4;
+  late final FutureOr<core::int>local6;
+  if(b) {
+    local2 = value;
+    local4 = 0;
+    local6 = 0;
+  }
+  local2 = value;
+  local4 = 0;
+  local6 = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_assigned.dart:50:3: Error: Late final variable 'local2' definitely assigned.
+  local2 = value; // error
+  ^^^^^^" in local2 = value;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_assigned.dart:51:3: Error: Late final variable 'local4' definitely assigned.
+  local4 = 0; // error
+  ^^^^^^" in local4 = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_assigned.dart:52:3: Error: Late final variable 'local6' definitely assigned.
+  local6 = 0; // error
+  ^^^^^^" in local6 = 0;
+}
+static method methodCompound() → dynamic {
+  late final core::int local4;
+  local4 = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_assigned.dart:80:3: Error: Late final variable 'local4' definitely assigned.
+  local4 += 0; // error
+  ^^^^^^" in local4 = local4.{core::num::+}(0){(core::num) → core::int};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/definitely_unassigned.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/definitely_unassigned.dart.weak.modular.expect
new file mode 100644
index 0000000..58f8535
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/definitely_unassigned.dart.weak.modular.expect
@@ -0,0 +1,236 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:16:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+//   local1; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:17:3: Error: Late variable 'local2' without initializer is definitely unassigned.
+//   local2; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:18:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+//   local3; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:19:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+//   local4; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:20:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+//   local5; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:21:3: Error: Late variable 'local6' without initializer is definitely unassigned.
+//   local6; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:34:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+//   local1; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:35:3: Error: Late variable 'local2' without initializer is definitely unassigned.
+//   local2; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:36:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+//   local3; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:37:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+//   local4; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:38:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+//   local5; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:39:3: Error: Late variable 'local6' without initializer is definitely unassigned.
+//   local6; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:62:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+//   local1; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:64:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+//   local3; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:66:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+//   local5; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:90:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+//   local1; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:92:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+//   local3; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:94:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+//   local5; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:103:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+//   local3 += 0; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:104:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+//   local4 += 0; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:111:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+//   local3 += 0; // error
+//   ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned.dart:112:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+//   local4 += 0; // error
+//   ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+static field <T extends core::Object? = dynamic>(T%) → Null fieldDirect = <T extends core::Object? = dynamic>(T% value) → Null {
+  T% local1;
+  late T% local2;
+  core::int local3;
+  late core::int local4;
+  FutureOr<core::int>local5;
+  late FutureOr<core::int>local6;
+  late T% local7 = value;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:34:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+  local1; // error
+  ^^^^^^" in local1;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:35:3: Error: Late variable 'local2' without initializer is definitely unassigned.
+  local2; // error
+  ^^^^^^" in local2;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:36:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+  local3; // error
+  ^^^^^^" in local3;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:37:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+  local4; // error
+  ^^^^^^" in local4;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:38:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+  local5; // error
+  ^^^^^^" in local5;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:39:3: Error: Late variable 'local6' without initializer is definitely unassigned.
+  local6; // error
+  ^^^^^^" in local6;
+  local7;
+};
+static field <T extends core::Object? = dynamic>(core::bool, T%) → Null fieldConditional = <T extends core::Object? = dynamic>(core::bool b, T% value) → Null {
+  T% local1;
+  late T% local2;
+  core::int local3;
+  late core::int local4;
+  FutureOr<core::int>local5;
+  late FutureOr<core::int>local6;
+  late T% local7 = value;
+  if(b) {
+    local1 = value;
+    local2 = value;
+    local3 = 0;
+    local4 = 0;
+    local5 = 0;
+    local6 = 0;
+    local7;
+  }
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:90:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+  local1; // error
+  ^^^^^^" in local1;
+  local2;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:92:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+  local3; // error
+  ^^^^^^" in local3;
+  local4;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:94:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+  local5; // error
+  ^^^^^^" in local5;
+  local6;
+  local7;
+};
+static field () → Null fieldCompound = () → Null {
+  core::int local3;
+  late core::int local4;
+  local3 = invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:111:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+  local3 += 0; // error
+  ^^^^^^" in local3.{core::num::+}(0){(core::num) → core::int};
+  local4 = invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:112:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+  local4 += 0; // error
+  ^^^^^^" in local4.{core::num::+}(0){(core::num) → core::int};
+};
+static method methodDirect<T extends core::Object? = dynamic>(self::methodDirect::T% value) → dynamic {
+  self::methodDirect::T% local1;
+  late self::methodDirect::T% local2;
+  core::int local3;
+  late core::int local4;
+  FutureOr<core::int>local5;
+  late FutureOr<core::int>local6;
+  late self::methodDirect::T% local7 = value;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:16:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+  local1; // error
+  ^^^^^^" in local1;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:17:3: Error: Late variable 'local2' without initializer is definitely unassigned.
+  local2; // error
+  ^^^^^^" in local2;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:18:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+  local3; // error
+  ^^^^^^" in local3;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:19:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+  local4; // error
+  ^^^^^^" in local4;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:20:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+  local5; // error
+  ^^^^^^" in local5;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:21:3: Error: Late variable 'local6' without initializer is definitely unassigned.
+  local6; // error
+  ^^^^^^" in local6;
+  local7;
+}
+static method methodConditional<T extends core::Object? = dynamic>(core::bool b, self::methodConditional::T% value) → dynamic {
+  self::methodConditional::T% local1;
+  late self::methodConditional::T% local2;
+  core::int local3;
+  late core::int local4;
+  FutureOr<core::int>local5;
+  late FutureOr<core::int>local6;
+  late self::methodConditional::T% local7 = value;
+  if(b) {
+    local1 = value;
+    local2 = value;
+    local3 = 0;
+    local4 = 0;
+    local5 = 0;
+    local6 = 0;
+    local7 = value;
+  }
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:62:3: Error: Non-nullable variable 'local1' must be assigned before it can be used.
+  local1; // error
+  ^^^^^^" in local1;
+  local2;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:64:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+  local3; // error
+  ^^^^^^" in local3;
+  local4;
+  invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:66:3: Error: Non-nullable variable 'local5' must be assigned before it can be used.
+  local5; // error
+  ^^^^^^" in local5;
+  local6;
+  local7;
+}
+static method methodCompound() → dynamic {
+  core::int local3;
+  late core::int local4;
+  local3 = invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:103:3: Error: Non-nullable variable 'local3' must be assigned before it can be used.
+  local3 += 0; // error
+  ^^^^^^" in local3.{core::num::+}(0){(core::num) → core::int};
+  local4 = invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned.dart:104:3: Error: Late variable 'local4' without initializer is definitely unassigned.
+  local4 += 0; // error
+  ^^^^^^" in local4.{core::num::+}(0){(core::num) → core::int};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/definitely_unassigned_late_local_variables.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/definitely_unassigned_late_local_variables.dart.weak.modular.expect
new file mode 100644
index 0000000..677a9bb
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/definitely_unassigned_late_local_variables.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned_late_local_variables.dart:15:9: Error: Late variable 'value' without initializer is definitely unassigned.
+//     bar(value); // Error.
+//         ^^^^^
+//
+// pkg/front_end/testcases/nnbd/definitely_unassigned_late_local_variables.dart:16:12: Error: Late variable 'intValue' without initializer is definitely unassigned.
+//     barInt(intValue); // Error.
+//            ^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+  method bar(covariant-by-class self::A::T% value) → dynamic {}
+  method barInt(core::int value) → dynamic {}
+  method foo() → dynamic {
+    late self::A::T% value;
+    late core::int intValue;
+    this.{self::A::bar}(invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned_late_local_variables.dart:15:9: Error: Late variable 'value' without initializer is definitely unassigned.
+    bar(value); // Error.
+        ^^^^^" in value){(self::A::T%) → dynamic};
+    this.{self::A::barInt}(invalid-expression "pkg/front_end/testcases/nnbd/definitely_unassigned_late_local_variables.dart:16:12: Error: Late variable 'intValue' without initializer is definitely unassigned.
+    barInt(intValue); // Error.
+           ^^^^^^^^" in intValue){(core::int) → dynamic};
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/demote_closure_types.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/demote_closure_types.dart.weak.modular.expect
new file mode 100644
index 0000000..d3ad413
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/demote_closure_types.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/demote_closure_types.dart:8:17: Error: A value of type 'T' can't be assigned to a variable of type 'String'.
+//     String s = f();
+//                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method method<T extends core::Object? = dynamic>(self::method::T% a, self::method::T% b) → dynamic {
+  if(a is{ForNonNullableByDefault} core::String) {
+    () → self::method::T% f = () → self::method::T% => a{self::method::T% & core::String /* '%' & '!' = '!' */};
+    core::String s = invalid-expression "pkg/front_end/testcases/nnbd/demote_closure_types.dart:8:17: Error: A value of type 'T' can't be assigned to a variable of type 'String'.
+    String s = f();
+                ^" in f(){() → self::method::T%} as{TypeError,ForNonNullableByDefault} core::String;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/duplicate_import.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/duplicate_import.dart.weak.modular.expect
new file mode 100644
index 0000000..78771c5
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/duplicate_import.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+
+import "org-dartlang-testcase:///duplicate_import_lib1.dart";
+import "org-dartlang-testcase:///duplicate_import_lib2.dart";
+export "org-dartlang-testcase:///duplicate_import_lib1.dart";
+export "org-dartlang-testcase:///duplicate_import_lib2.dart";
+
+static method main() → dynamic {}
+
+library foo /*isNonNullableByDefault*/;
+import self as self2;
+
+
+library foo /*isNonNullableByDefault*/;
+import self as self3;
diff --git a/pkg/front_end/testcases/nnbd/duplicates_instance.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/duplicates_instance.dart.weak.modular.expect
new file mode 100644
index 0000000..36ed89b
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/duplicates_instance.dart.weak.modular.expect
@@ -0,0 +1,344 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:9:7: Error: 'instanceMethod' is already declared in this scope.
+//   int instanceMethod() => 2;
+//       ^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:8:7: Context: Previous declaration of 'instanceMethod'.
+//   int instanceMethod() => 1;
+//       ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:12:11: Error: 'instanceGetter' is already declared in this scope.
+//   int get instanceGetter => 2;
+//           ^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:11:11: Context: Previous declaration of 'instanceGetter'.
+//   int get instanceGetter => 1;
+//           ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:18:12: Error: 'instanceSetter' is already declared in this scope.
+//   void set instanceSetter(value) {
+//            ^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:14:12: Context: Previous declaration of 'instanceSetter'.
+//   void set instanceSetter(value) {
+//            ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:23:7: Error: 'instanceField' is already declared in this scope.
+//   int instanceField = 2;
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:22:7: Context: Previous declaration of 'instanceField'.
+//   int instanceField = 1;
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:48:13: Error: 'instanceDuplicateFieldAndSetter' is already declared in this scope.
+//   final int instanceDuplicateFieldAndSetter = 2;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:47:13: Context: Previous declaration of 'instanceDuplicateFieldAndSetter'.
+//   final int instanceDuplicateFieldAndSetter = 1;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:58:12: Error: 'instanceFieldAndDuplicateSetter' is already declared in this scope.
+//   void set instanceFieldAndDuplicateSetter(int value) {
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:54:12: Context: Previous declaration of 'instanceFieldAndDuplicateSetter'.
+//   void set instanceFieldAndDuplicateSetter(int value) {
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:63:13: Error: 'instanceDuplicateFieldAndDuplicateSetter' is already declared in this scope.
+//   final int instanceDuplicateFieldAndDuplicateSetter = 2;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:62:13: Context: Previous declaration of 'instanceDuplicateFieldAndDuplicateSetter'.
+//   final int instanceDuplicateFieldAndDuplicateSetter = 1;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:68:12: Error: 'instanceDuplicateFieldAndDuplicateSetter' is already declared in this scope.
+//   void set instanceDuplicateFieldAndDuplicateSetter(int value) {
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:64:12: Context: Previous declaration of 'instanceDuplicateFieldAndDuplicateSetter'.
+//   void set instanceDuplicateFieldAndDuplicateSetter(int value) {
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:26:12: Error: Conflicts with the implicit setter of the field 'instanceFieldAndSetter1'.
+//   void set instanceFieldAndSetter1(int value) {
+//            ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:25:7: Error: Conflicts with setter 'instanceFieldAndSetter1'.
+//   int instanceFieldAndSetter1 = 1;
+//       ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:30:12: Error: Conflicts with the implicit setter of the field 'instanceFieldAndSetter2'.
+//   void set instanceFieldAndSetter2(int value) {
+//            ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:34:7: Error: Conflicts with setter 'instanceFieldAndSetter2'.
+//   int instanceFieldAndSetter2 = 1;
+//       ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:37:12: Error: Conflicts with the implicit setter of the field 'instanceLateFinalFieldAndSetter1'.
+//   void set instanceLateFinalFieldAndSetter1(int value) {
+//            ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:36:18: Error: Conflicts with setter 'instanceLateFinalFieldAndSetter1'.
+//   late final int instanceLateFinalFieldAndSetter1;
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:41:12: Error: Conflicts with the implicit setter of the field 'instanceLateFinalFieldAndSetter2'.
+//   void set instanceLateFinalFieldAndSetter2(int value) {
+//            ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:45:18: Error: Conflicts with setter 'instanceLateFinalFieldAndSetter2'.
+//   late final int instanceLateFinalFieldAndSetter2;
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:73:12: Error: 'instanceMethodAndSetter1' is already declared in this scope.
+//   void set instanceMethodAndSetter1(int value) {
+//            ^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:72:7: Context: Previous declaration of 'instanceMethodAndSetter1'.
+//   int instanceMethodAndSetter1() => 1;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:81:7: Error: 'instanceMethodAndSetter2' is already declared in this scope.
+//   int instanceMethodAndSetter2() => 1;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:77:12: Context: Previous declaration of 'instanceMethodAndSetter2'.
+//   void set instanceMethodAndSetter2(int value) {
+//            ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:86:5: Error: Can't use 'instanceMethod' because it is declared more than once.
+//   c.instanceMethod();
+//     ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:86:5: Error: The method 'instanceMethod' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'instanceMethod'.
+//   c.instanceMethod();
+//     ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:87:6: Error: Can't use 'instanceMethod' because it is declared more than once.
+//   (c.instanceMethod)();
+//      ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:87:6: Error: The getter 'instanceMethod' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceMethod'.
+//   (c.instanceMethod)();
+//      ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:88:5: Error: Can't use 'instanceGetter' because it is declared more than once.
+//   c.instanceGetter;
+//     ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:88:5: Error: The getter 'instanceGetter' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceGetter'.
+//   c.instanceGetter;
+//     ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:89:5: Error: Can't use 'instanceSetter' because it is declared more than once.
+//   c.instanceSetter = 0;
+//     ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:89:5: Error: The setter 'instanceSetter' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceSetter'.
+//   c.instanceSetter = 0;
+//     ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:90:5: Error: Can't use 'instanceField' because it is declared more than once.
+//   c.instanceField;
+//     ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:90:5: Error: The getter 'instanceField' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceField'.
+//   c.instanceField;
+//     ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:91:5: Error: Can't use 'instanceField' because it is declared more than once.
+//   c.instanceField = 0;
+//     ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:91:5: Error: The setter 'instanceField' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceField'.
+//   c.instanceField = 0;
+//     ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:92:5: Error: Can't use 'instanceDuplicateFieldAndSetter' because it is declared more than once.
+//   c.instanceDuplicateFieldAndSetter;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:92:5: Error: The getter 'instanceDuplicateFieldAndSetter' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceDuplicateFieldAndSetter'.
+//   c.instanceDuplicateFieldAndSetter;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:95:5: Error: Can't use 'instanceFieldAndDuplicateSetter' because it is declared more than once.
+//   c.instanceFieldAndDuplicateSetter = 0;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:95:5: Error: The setter 'instanceFieldAndDuplicateSetter' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceFieldAndDuplicateSetter'.
+//   c.instanceFieldAndDuplicateSetter = 0;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:96:5: Error: Can't use 'instanceDuplicateFieldAndDuplicateSetter' because it is declared more than once.
+//   c.instanceDuplicateFieldAndDuplicateSetter;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:96:5: Error: The getter 'instanceDuplicateFieldAndDuplicateSetter' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceDuplicateFieldAndDuplicateSetter'.
+//   c.instanceDuplicateFieldAndDuplicateSetter;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:97:5: Error: Can't use 'instanceDuplicateFieldAndDuplicateSetter' because it is declared more than once.
+//   c.instanceDuplicateFieldAndDuplicateSetter = 0;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance.dart:97:5: Error: The setter 'instanceDuplicateFieldAndDuplicateSetter' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceDuplicateFieldAndDuplicateSetter'.
+//   c.instanceDuplicateFieldAndDuplicateSetter = 0;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int instanceField = null;
+  field core::int instanceFieldAndSetter1 = 1;
+  field core::int instanceFieldAndSetter2 = 1;
+  late final [setter] field core::int instanceLateFinalFieldAndSetter1;
+  late final [setter] field core::int instanceLateFinalFieldAndSetter2;
+  final field core::int instanceDuplicateFieldAndSetter = null;
+  final field core::int instanceFieldAndDuplicateSetter = 1;
+  final field core::int instanceDuplicateFieldAndDuplicateSetter = null;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  method instanceMethod() → core::int
+    return 1;
+  get instanceGetter() → core::int
+    return 1;
+  set instanceSetter(dynamic value) → void {
+    self::result = 1;
+  }
+  set instanceDuplicateFieldAndSetter(core::int value) → void {
+    self::result = 3;
+  }
+  set instanceFieldAndDuplicateSetter(core::int value) → void {
+    self::result = 2;
+  }
+  set instanceDuplicateFieldAndDuplicateSetter(core::int value) → void {
+    self::result = 3;
+  }
+  method instanceMethodAndSetter1() → core::int
+    return 1;
+  set instanceMethodAndSetter1(core::int value) → void {
+    self::result = 2;
+  }
+  set instanceMethodAndSetter2(core::int value) → void {
+    self::result = 2;
+  }
+  method instanceMethodAndSetter2() → core::int
+    return 1;
+}
+static field dynamic result;
+static method test() → dynamic {
+  self::Class c = new self::Class::•();
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance.dart:86:5: Error: The method 'instanceMethod' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'instanceMethod'.
+  c.instanceMethod();
+    ^^^^^^^^^^^^^^" in c{<unresolved>}.instanceMethod();
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance.dart:87:6: Error: The getter 'instanceMethod' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceMethod'.
+  (c.instanceMethod)();
+     ^^^^^^^^^^^^^^" in c{<unresolved>}.instanceMethod{dynamic}.call();
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance.dart:88:5: Error: The getter 'instanceGetter' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceGetter'.
+  c.instanceGetter;
+    ^^^^^^^^^^^^^^" in c{<unresolved>}.instanceGetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance.dart:89:5: Error: The setter 'instanceSetter' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceSetter'.
+  c.instanceSetter = 0;
+    ^^^^^^^^^^^^^^" in c{<unresolved>}.instanceSetter = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance.dart:90:5: Error: The getter 'instanceField' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceField'.
+  c.instanceField;
+    ^^^^^^^^^^^^^" in c{<unresolved>}.instanceField;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance.dart:91:5: Error: The setter 'instanceField' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceField'.
+  c.instanceField = 0;
+    ^^^^^^^^^^^^^" in c{<unresolved>}.instanceField = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance.dart:92:5: Error: The getter 'instanceDuplicateFieldAndSetter' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceDuplicateFieldAndSetter'.
+  c.instanceDuplicateFieldAndSetter;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceDuplicateFieldAndSetter;
+  c.{self::Class::instanceDuplicateFieldAndSetter} = 0;
+  c.{self::Class::instanceFieldAndDuplicateSetter}{core::int};
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance.dart:95:5: Error: The setter 'instanceFieldAndDuplicateSetter' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceFieldAndDuplicateSetter'.
+  c.instanceFieldAndDuplicateSetter = 0;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceFieldAndDuplicateSetter = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance.dart:96:5: Error: The getter 'instanceDuplicateFieldAndDuplicateSetter' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceDuplicateFieldAndDuplicateSetter'.
+  c.instanceDuplicateFieldAndDuplicateSetter;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceDuplicateFieldAndDuplicateSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance.dart:97:5: Error: The setter 'instanceDuplicateFieldAndDuplicateSetter' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/duplicates_instance.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceDuplicateFieldAndDuplicateSetter'.
+  c.instanceDuplicateFieldAndDuplicateSetter = 0;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceDuplicateFieldAndDuplicateSetter = 0;
+}
+static method main() → dynamic {
+  self::Class c = new self::Class::•();
+  c.{self::Class::instanceFieldAndSetter1} = 0;
+  self::expect(null, self::result);
+  self::expect(0, c.{self::Class::instanceFieldAndSetter1}{core::int});
+  self::result = null;
+  c.{self::Class::instanceFieldAndSetter2} = 0;
+  self::expect(null, self::result);
+  self::expect(0, c.{self::Class::instanceFieldAndSetter2}{core::int});
+  self::result = null;
+  c.{self::Class::instanceLateFinalFieldAndSetter1} = 0;
+  self::expect(null, self::result);
+  self::expect(0, c.{self::Class::instanceLateFinalFieldAndSetter1}{core::int});
+  self::result = null;
+  c.{self::Class::instanceLateFinalFieldAndSetter2} = 0;
+  self::expect(null, self::result);
+  self::expect(0, c.{self::Class::instanceLateFinalFieldAndSetter2}{core::int});
+  self::result = null;
+  self::expect(1, c.{self::Class::instanceMethodAndSetter1}(){() → core::int});
+  c.{self::Class::instanceMethodAndSetter1} = 0;
+  self::expect(2, self::result);
+  self::result = null;
+  self::expect(1, c.{self::Class::instanceMethodAndSetter2}(){() → core::int});
+  c.{self::Class::instanceMethodAndSetter2} = 0;
+  self::expect(2, self::result);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print(e);
+    return;
+  }
+  throw "Expected exception.";
+}
diff --git a/pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart.weak.modular.expect
new file mode 100644
index 0000000..92b80e8
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart.weak.modular.expect
@@ -0,0 +1,432 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:9:7: Error: 'instanceMethod' is already declared in this scope.
+//   int instanceMethod() => 2;
+//       ^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:8:7: Context: Previous declaration of 'instanceMethod'.
+//   int instanceMethod() => 1;
+//       ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:12:11: Error: 'instanceGetter' is already declared in this scope.
+//   int get instanceGetter => 2;
+//           ^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:11:11: Context: Previous declaration of 'instanceGetter'.
+//   int get instanceGetter => 1;
+//           ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:18:12: Error: 'instanceSetter' is already declared in this scope.
+//   void set instanceSetter(value) {
+//            ^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:14:12: Context: Previous declaration of 'instanceSetter'.
+//   void set instanceSetter(value) {
+//            ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:22:7: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int instanceField = 1;
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:23:7: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int instanceField = 2;
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:23:7: Error: 'instanceField' is already declared in this scope.
+//   int instanceField = 2;
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:22:7: Context: Previous declaration of 'instanceField'.
+//   int instanceField = 1;
+//       ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:25:7: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int instanceFieldAndSetter1 = 1;
+//       ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:33:7: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int instanceFieldAndSetter2 = 1;
+//       ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:35:18: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   late final int instanceLateFinalFieldAndSetter1;
+//                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:43:18: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   late final int instanceLateFinalFieldAndSetter2;
+//                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:45:13: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   final int instanceDuplicateFieldAndSetter = 1;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:46:13: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   final int instanceDuplicateFieldAndSetter = 2;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:46:13: Error: 'instanceDuplicateFieldAndSetter' is already declared in this scope.
+//   final int instanceDuplicateFieldAndSetter = 2;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:45:13: Context: Previous declaration of 'instanceDuplicateFieldAndSetter'.
+//   final int instanceDuplicateFieldAndSetter = 1;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:51:13: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   final int instanceFieldAndDuplicateSetter = 1;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:56:12: Error: 'instanceFieldAndDuplicateSetter' is already declared in this scope.
+//   void set instanceFieldAndDuplicateSetter(int value) {
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:52:12: Context: Previous declaration of 'instanceFieldAndDuplicateSetter'.
+//   void set instanceFieldAndDuplicateSetter(int value) {
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:60:13: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   final int instanceDuplicateFieldAndDuplicateSetter = 1;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:61:13: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   final int instanceDuplicateFieldAndDuplicateSetter = 2;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:61:13: Error: 'instanceDuplicateFieldAndDuplicateSetter' is already declared in this scope.
+//   final int instanceDuplicateFieldAndDuplicateSetter = 2;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:60:13: Context: Previous declaration of 'instanceDuplicateFieldAndDuplicateSetter'.
+//   final int instanceDuplicateFieldAndDuplicateSetter = 1;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:66:12: Error: 'instanceDuplicateFieldAndDuplicateSetter' is already declared in this scope.
+//   void set instanceDuplicateFieldAndDuplicateSetter(int value) {
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:62:12: Context: Previous declaration of 'instanceDuplicateFieldAndDuplicateSetter'.
+//   void set instanceDuplicateFieldAndDuplicateSetter(int value) {
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:26:12: Error: Conflicts with the implicit setter of the field 'instanceFieldAndSetter1'.
+//   void set instanceFieldAndSetter1(int value) {
+//            ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:25:7: Error: Conflicts with setter 'instanceFieldAndSetter1'.
+//   int instanceFieldAndSetter1 = 1;
+//       ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:30:12: Error: Conflicts with the implicit setter of the field 'instanceFieldAndSetter2'.
+//   void set instanceFieldAndSetter2(int value) {
+//            ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:33:7: Error: Conflicts with setter 'instanceFieldAndSetter2'.
+//   int instanceFieldAndSetter2 = 1;
+//       ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:36:12: Error: Conflicts with the implicit setter of the field 'instanceLateFinalFieldAndSetter1'.
+//   void set instanceLateFinalFieldAndSetter1(int value) {
+//            ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:35:18: Error: Conflicts with setter 'instanceLateFinalFieldAndSetter1'.
+//   late final int instanceLateFinalFieldAndSetter1;
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:40:12: Error: Conflicts with the implicit setter of the field 'instanceLateFinalFieldAndSetter2'.
+//   void set instanceLateFinalFieldAndSetter2(int value) {
+//            ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:43:18: Error: Conflicts with setter 'instanceLateFinalFieldAndSetter2'.
+//   late final int instanceLateFinalFieldAndSetter2;
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:71:12: Error: Conflicts with member 'instanceMethodAndSetter1'.
+//   void set instanceMethodAndSetter1(int value) {
+//            ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:70:7: Error: Conflicts with setter 'instanceMethodAndSetter1'.
+//   int instanceMethodAndSetter1() => 1;
+//       ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:75:12: Error: Conflicts with member 'instanceMethodAndSetter2'.
+//   void set instanceMethodAndSetter2(int value) {
+//            ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:78:7: Error: Conflicts with setter 'instanceMethodAndSetter2'.
+//   int instanceMethodAndSetter2() => 1;
+//       ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:83:5: Error: The method 'instanceMethod' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing method, or defining a method named 'instanceMethod'.
+//   c.instanceMethod();
+//     ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:84:6: Error: The getter 'instanceMethod' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceMethod'.
+//   (c.instanceMethod)();
+//      ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:85:5: Error: The getter 'instanceGetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceGetter'.
+//   c.instanceGetter;
+//     ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:86:5: Error: The setter 'instanceSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceSetter'.
+//   c.instanceSetter = 0;
+//     ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:87:5: Error: The getter 'instanceField' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceField'.
+//   c.instanceField;
+//     ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:88:5: Error: The setter 'instanceField' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceField'.
+//   c.instanceField = 0;
+//     ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:89:5: Error: The getter 'instanceFieldAndSetter1' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceFieldAndSetter1'.
+//   c.instanceFieldAndSetter1;
+//     ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:90:5: Error: The setter 'instanceFieldAndSetter1' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceFieldAndSetter1'.
+//   c.instanceFieldAndSetter1 = 0;
+//     ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:91:5: Error: The getter 'instanceFieldAndSetter2' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceFieldAndSetter2'.
+//   c.instanceFieldAndSetter2;
+//     ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:92:5: Error: The setter 'instanceFieldAndSetter2' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceFieldAndSetter2'.
+//   c.instanceFieldAndSetter2 = 0;
+//     ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:93:5: Error: The getter 'instanceLateFinalFieldAndSetter1' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceLateFinalFieldAndSetter1'.
+//   c.instanceLateFinalFieldAndSetter1;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:94:5: Error: The setter 'instanceLateFinalFieldAndSetter1' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceLateFinalFieldAndSetter1'.
+//   c.instanceLateFinalFieldAndSetter1 = 0;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:95:5: Error: The getter 'instanceLateFinalFieldAndSetter2' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceLateFinalFieldAndSetter2'.
+//   c.instanceLateFinalFieldAndSetter2;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:96:5: Error: The setter 'instanceLateFinalFieldAndSetter2' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceLateFinalFieldAndSetter2'.
+//   c.instanceLateFinalFieldAndSetter2 = 0;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:97:5: Error: The getter 'instanceDuplicateFieldAndSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceDuplicateFieldAndSetter'.
+//   c.instanceDuplicateFieldAndSetter;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:98:5: Error: The getter 'instanceFieldAndDuplicateSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceFieldAndDuplicateSetter'.
+//   c.instanceFieldAndDuplicateSetter;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:99:5: Error: The setter 'instanceFieldAndDuplicateSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceFieldAndDuplicateSetter'.
+//   c.instanceFieldAndDuplicateSetter = 0;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:100:5: Error: The getter 'instanceDuplicateFieldAndDuplicateSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceDuplicateFieldAndDuplicateSetter'.
+//   c.instanceDuplicateFieldAndDuplicateSetter;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:101:5: Error: The setter 'instanceDuplicateFieldAndDuplicateSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceDuplicateFieldAndDuplicateSetter'.
+//   c.instanceDuplicateFieldAndDuplicateSetter = 0;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+extension Extension on core::int {
+  method instanceMethod = self::Extension|instanceMethod;
+  tearoff instanceMethod = self::Extension|get#instanceMethod;
+  get instanceGetter = self::Extension|get#instanceGetter;
+  field instanceField = self::Extension|instanceField;
+  field instanceFieldAndSetter1 = self::Extension|instanceFieldAndSetter1;
+  field instanceFieldAndSetter2 = self::Extension|instanceFieldAndSetter2;
+  field instanceLateFinalFieldAndSetter1 = self::Extension|instanceLateFinalFieldAndSetter1;
+  field instanceLateFinalFieldAndSetter2 = self::Extension|instanceLateFinalFieldAndSetter2;
+  field instanceDuplicateFieldAndSetter = self::Extension|instanceDuplicateFieldAndSetter;
+  field instanceFieldAndDuplicateSetter = self::Extension|instanceFieldAndDuplicateSetter;
+  field instanceDuplicateFieldAndDuplicateSetter = self::Extension|instanceDuplicateFieldAndDuplicateSetter;
+  method instanceMethodAndSetter1 = self::Extension|instanceMethodAndSetter1;
+  tearoff instanceMethodAndSetter1 = self::Extension|get#instanceMethodAndSetter1;
+  method instanceMethodAndSetter2 = self::Extension|instanceMethodAndSetter2;
+  tearoff instanceMethodAndSetter2 = self::Extension|get#instanceMethodAndSetter2;
+  set instanceSetter = self::Extension|set#instanceSetter;
+  set instanceDuplicateFieldAndSetter = self::Extension|set#instanceDuplicateFieldAndSetter;
+  set instanceFieldAndDuplicateSetter = self::Extension|set#instanceFieldAndDuplicateSetter;
+  set instanceDuplicateFieldAndDuplicateSetter = self::Extension|set#instanceDuplicateFieldAndDuplicateSetter;
+  set instanceMethodAndSetter1 = self::Extension|set#instanceMethodAndSetter1;
+  set instanceMethodAndSetter2 = self::Extension|set#instanceMethodAndSetter2;
+}
+static field dynamic result;
+static field core::int Extension|instanceField;
+static field core::int Extension|instanceFieldAndSetter1 = 1;
+static field core::int Extension|instanceFieldAndSetter2 = 1;
+late static final [setter] field core::int Extension|instanceLateFinalFieldAndSetter1;
+late static final [setter] field core::int Extension|instanceLateFinalFieldAndSetter2;
+static final field core::int Extension|instanceDuplicateFieldAndSetter;
+static final field core::int Extension|instanceFieldAndDuplicateSetter = 1;
+static final field core::int Extension|instanceDuplicateFieldAndDuplicateSetter;
+static method Extension|instanceMethod(lowered final core::int #this) → core::int
+  return 1;
+static method Extension|get#instanceMethod(lowered final core::int #this) → () → core::int
+  return () → core::int => self::Extension|instanceMethod(#this);
+static method Extension|get#instanceGetter(lowered final core::int #this) → core::int
+  return 1;
+static method Extension|set#instanceSetter(lowered final core::int #this, dynamic value) → void {
+  self::result = 1;
+}
+static method Extension|set#instanceDuplicateFieldAndSetter(lowered final core::int #this, core::int value) → void {
+  self::result = 3;
+}
+static method Extension|set#instanceFieldAndDuplicateSetter(lowered final core::int #this, core::int value) → void {
+  self::result = 2;
+}
+static method Extension|set#instanceDuplicateFieldAndDuplicateSetter(lowered final core::int #this, core::int value) → void {
+  self::result = 3;
+}
+static method Extension|instanceMethodAndSetter1(lowered final core::int #this) → core::int
+  return 1;
+static method Extension|get#instanceMethodAndSetter1(lowered final core::int #this) → () → core::int
+  return () → core::int => self::Extension|instanceMethodAndSetter1(#this);
+static method Extension|set#instanceMethodAndSetter1(lowered final core::int #this, core::int value) → void {
+  self::result = 2;
+}
+static method Extension|set#instanceMethodAndSetter2(lowered final core::int #this, core::int value) → void {
+  self::result = 2;
+}
+static method Extension|instanceMethodAndSetter2(lowered final core::int #this) → core::int
+  return 1;
+static method Extension|get#instanceMethodAndSetter2(lowered final core::int #this) → () → core::int
+  return () → core::int => self::Extension|instanceMethodAndSetter2(#this);
+static method test() → dynamic {
+  core::int c = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:83:5: Error: The method 'instanceMethod' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing method, or defining a method named 'instanceMethod'.
+  c.instanceMethod();
+    ^^^^^^^^^^^^^^" in c{<unresolved>}.instanceMethod();
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:84:6: Error: The getter 'instanceMethod' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceMethod'.
+  (c.instanceMethod)();
+     ^^^^^^^^^^^^^^" in c{<unresolved>}.instanceMethod{dynamic}.call();
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:85:5: Error: The getter 'instanceGetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceGetter'.
+  c.instanceGetter;
+    ^^^^^^^^^^^^^^" in c{<unresolved>}.instanceGetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:86:5: Error: The setter 'instanceSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceSetter'.
+  c.instanceSetter = 0;
+    ^^^^^^^^^^^^^^" in c{<unresolved>}.instanceSetter = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:87:5: Error: The getter 'instanceField' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceField'.
+  c.instanceField;
+    ^^^^^^^^^^^^^" in c{<unresolved>}.instanceField;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:88:5: Error: The setter 'instanceField' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceField'.
+  c.instanceField = 0;
+    ^^^^^^^^^^^^^" in c{<unresolved>}.instanceField = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:89:5: Error: The getter 'instanceFieldAndSetter1' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceFieldAndSetter1'.
+  c.instanceFieldAndSetter1;
+    ^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceFieldAndSetter1;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:90:5: Error: The setter 'instanceFieldAndSetter1' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceFieldAndSetter1'.
+  c.instanceFieldAndSetter1 = 0;
+    ^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceFieldAndSetter1 = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:91:5: Error: The getter 'instanceFieldAndSetter2' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceFieldAndSetter2'.
+  c.instanceFieldAndSetter2;
+    ^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceFieldAndSetter2;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:92:5: Error: The setter 'instanceFieldAndSetter2' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceFieldAndSetter2'.
+  c.instanceFieldAndSetter2 = 0;
+    ^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceFieldAndSetter2 = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:93:5: Error: The getter 'instanceLateFinalFieldAndSetter1' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceLateFinalFieldAndSetter1'.
+  c.instanceLateFinalFieldAndSetter1;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceLateFinalFieldAndSetter1;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:94:5: Error: The setter 'instanceLateFinalFieldAndSetter1' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceLateFinalFieldAndSetter1'.
+  c.instanceLateFinalFieldAndSetter1 = 0;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceLateFinalFieldAndSetter1 = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:95:5: Error: The getter 'instanceLateFinalFieldAndSetter2' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceLateFinalFieldAndSetter2'.
+  c.instanceLateFinalFieldAndSetter2;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceLateFinalFieldAndSetter2;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:96:5: Error: The setter 'instanceLateFinalFieldAndSetter2' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceLateFinalFieldAndSetter2'.
+  c.instanceLateFinalFieldAndSetter2 = 0;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceLateFinalFieldAndSetter2 = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:97:5: Error: The getter 'instanceDuplicateFieldAndSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceDuplicateFieldAndSetter'.
+  c.instanceDuplicateFieldAndSetter;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceDuplicateFieldAndSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:98:5: Error: The getter 'instanceFieldAndDuplicateSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceFieldAndDuplicateSetter'.
+  c.instanceFieldAndDuplicateSetter;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceFieldAndDuplicateSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:99:5: Error: The setter 'instanceFieldAndDuplicateSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceFieldAndDuplicateSetter'.
+  c.instanceFieldAndDuplicateSetter = 0;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceFieldAndDuplicateSetter = 0;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:100:5: Error: The getter 'instanceDuplicateFieldAndDuplicateSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'instanceDuplicateFieldAndDuplicateSetter'.
+  c.instanceDuplicateFieldAndDuplicateSetter;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceDuplicateFieldAndDuplicateSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_instance_extension.dart:101:5: Error: The setter 'instanceDuplicateFieldAndDuplicateSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'instanceDuplicateFieldAndDuplicateSetter'.
+  c.instanceDuplicateFieldAndDuplicateSetter = 0;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.instanceDuplicateFieldAndDuplicateSetter = 0;
+}
+static method main() → dynamic {
+  core::int c = 0;
+  self::result = null;
+  self::Extension|set#instanceDuplicateFieldAndSetter(c, 0);
+  self::expect(3, self::result);
+  self::result = null;
+  self::expect(1, self::Extension|instanceMethodAndSetter1(c));
+  self::Extension|set#instanceMethodAndSetter1(c, 0);
+  self::expect(2, self::result);
+  self::result = null;
+  self::expect(1, self::Extension|instanceMethodAndSetter2(c));
+  self::Extension|set#instanceMethodAndSetter2(c, 0);
+  self::expect(2, self::result);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print(e);
+    return;
+  }
+  throw "Expected exception.";
+}
diff --git a/pkg/front_end/testcases/nnbd/duplicates_static.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/duplicates_static.dart.weak.modular.expect
new file mode 100644
index 0000000..d487082
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/duplicates_static.dart.weak.modular.expect
@@ -0,0 +1,293 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:9:14: Error: 'staticMethod' is already declared in this scope.
+//   static int staticMethod() => 2;
+//              ^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:8:14: Context: Previous declaration of 'staticMethod'.
+//   static int staticMethod() => 1;
+//              ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:12:18: Error: 'staticGetter' is already declared in this scope.
+//   static int get staticGetter => 2;
+//                  ^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:11:18: Context: Previous declaration of 'staticGetter'.
+//   static int get staticGetter => 1;
+//                  ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:18:19: Error: 'staticSetter' is already declared in this scope.
+//   static void set staticSetter(value) {
+//                   ^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:14:19: Context: Previous declaration of 'staticSetter'.
+//   static void set staticSetter(value) {
+//                   ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:23:14: Error: 'staticField' is already declared in this scope.
+//   static int staticField = 2;
+//              ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:22:14: Context: Previous declaration of 'staticField'.
+//   static int staticField = 1;
+//              ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:48:20: Error: 'staticDuplicateFieldAndSetter' is already declared in this scope.
+//   static final int staticDuplicateFieldAndSetter = 2;
+//                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:47:20: Context: Previous declaration of 'staticDuplicateFieldAndSetter'.
+//   static final int staticDuplicateFieldAndSetter = 1;
+//                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:58:19: Error: 'staticFieldAndDuplicateSetter' is already declared in this scope.
+//   static void set staticFieldAndDuplicateSetter(int value) {
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:54:19: Context: Previous declaration of 'staticFieldAndDuplicateSetter'.
+//   static void set staticFieldAndDuplicateSetter(int value) {
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:63:20: Error: 'staticDuplicateFieldAndDuplicateSetter' is already declared in this scope.
+//   static final int staticDuplicateFieldAndDuplicateSetter = 2;
+//                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:62:20: Context: Previous declaration of 'staticDuplicateFieldAndDuplicateSetter'.
+//   static final int staticDuplicateFieldAndDuplicateSetter = 1;
+//                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:68:19: Error: 'staticDuplicateFieldAndDuplicateSetter' is already declared in this scope.
+//   static void set staticDuplicateFieldAndDuplicateSetter(int value) {
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:64:19: Context: Previous declaration of 'staticDuplicateFieldAndDuplicateSetter'.
+//   static void set staticDuplicateFieldAndDuplicateSetter(int value) {
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:26:19: Error: Conflicts with the implicit setter of the field 'staticFieldAndSetter1'.
+//   static void set staticFieldAndSetter1(int value) {
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:25:14: Error: Conflicts with setter 'staticFieldAndSetter1'.
+//   static int staticFieldAndSetter1 = 1;
+//              ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:30:19: Error: Conflicts with the implicit setter of the field 'staticFieldAndSetter2'.
+//   static void set staticFieldAndSetter2(int value) {
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:34:14: Error: Conflicts with setter 'staticFieldAndSetter2'.
+//   static int staticFieldAndSetter2 = 1;
+//              ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:37:19: Error: Conflicts with the implicit setter of the field 'staticLateFinalFieldAndSetter1'.
+//   static void set staticLateFinalFieldAndSetter1(int value) {
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:36:25: Error: Conflicts with setter 'staticLateFinalFieldAndSetter1'.
+//   static late final int staticLateFinalFieldAndSetter1;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:41:19: Error: Conflicts with the implicit setter of the field 'staticLateFinalFieldAndSetter2'.
+//   static void set staticLateFinalFieldAndSetter2(int value) {
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:45:25: Error: Conflicts with setter 'staticLateFinalFieldAndSetter2'.
+//   static late final int staticLateFinalFieldAndSetter2;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:73:19: Error: 'staticMethodAndSetter1' is already declared in this scope.
+//   static void set staticMethodAndSetter1(int value) {
+//                   ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:72:14: Context: Previous declaration of 'staticMethodAndSetter1'.
+//   static int staticMethodAndSetter1() => 1;
+//              ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:81:14: Error: 'staticMethodAndSetter2' is already declared in this scope.
+//   static int staticMethodAndSetter2() => 1;
+//              ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:77:19: Context: Previous declaration of 'staticMethodAndSetter2'.
+//   static void set staticMethodAndSetter2(int value) {
+//                   ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:85:9: Error: Can't use 'staticMethod' because it is declared more than once.
+//   Class.staticMethod();
+//         ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:86:10: Error: Can't use 'staticMethod' because it is declared more than once.
+//   (Class.staticMethod)();
+//          ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:87:9: Error: Can't use 'staticGetter' because it is declared more than once.
+//   Class.staticGetter;
+//         ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:88:9: Error: Can't use 'staticSetter' because it is declared more than once.
+//   Class.staticSetter = 0;
+//         ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:88:22: Error: Can't assign to this.
+//   Class.staticSetter = 0;
+//                      ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:89:9: Error: Can't use 'staticField' because it is declared more than once.
+//   Class.staticField;
+//         ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:90:9: Error: Can't use 'staticField' because it is declared more than once.
+//   Class.staticField = 0;
+//         ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:90:21: Error: Can't assign to this.
+//   Class.staticField = 0;
+//                     ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:91:9: Error: Can't use 'staticDuplicateFieldAndSetter' because it is declared more than once.
+//   Class.staticDuplicateFieldAndSetter;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:92:9: Error: Can't use 'staticDuplicateFieldAndSetter' because it is declared more than once.
+//   Class.staticDuplicateFieldAndSetter = 0;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:92:39: Error: Can't assign to this.
+//   Class.staticDuplicateFieldAndSetter = 0;
+//                                       ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:94:9: Error: Setter not found: 'staticFieldAndDuplicateSetter'.
+//   Class.staticFieldAndDuplicateSetter = 0;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:95:9: Error: Can't use 'staticDuplicateFieldAndDuplicateSetter' because it is declared more than once.
+//   Class.staticDuplicateFieldAndDuplicateSetter;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:96:9: Error: Can't use 'staticDuplicateFieldAndDuplicateSetter' because it is declared more than once.
+//   Class.staticDuplicateFieldAndDuplicateSetter = 0;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:96:48: Error: Can't assign to this.
+//   Class.staticDuplicateFieldAndDuplicateSetter = 0;
+//                                                ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:97:9: Error: Setter not found: 'staticMethodAndSetter1'.
+//   Class.staticMethodAndSetter1 = 0;
+//         ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static.dart:98:9: Error: Setter not found: 'staticMethodAndSetter2'.
+//   Class.staticMethodAndSetter2 = 0;
+//         ^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  static field core::int staticField = null;
+  static field core::int staticFieldAndSetter1 = 1;
+  static field core::int staticFieldAndSetter2 = 1;
+  late static final [setter] field core::int staticLateFinalFieldAndSetter1;
+  late static final [setter] field core::int staticLateFinalFieldAndSetter2;
+  static final field core::int staticDuplicateFieldAndSetter = null;
+  static final field core::int staticFieldAndDuplicateSetter = 1;
+  static final field core::int staticDuplicateFieldAndDuplicateSetter = null;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  static method staticMethod() → core::int
+    return 1;
+  static get staticGetter() → core::int
+    return 1;
+  static set staticSetter(dynamic value) → void {
+    self::result = 1;
+  }
+  static set staticDuplicateFieldAndSetter(core::int value) → void {
+    self::result = 3;
+  }
+  static set staticFieldAndDuplicateSetter(core::int value) → void {
+    self::result = 2;
+  }
+  static set staticDuplicateFieldAndDuplicateSetter(core::int value) → void {
+    self::result = 3;
+  }
+  static method staticMethodAndSetter1() → core::int
+    return 1;
+  static set staticMethodAndSetter1(core::int value) → void {
+    self::result = 2;
+  }
+  static set staticMethodAndSetter2(core::int value) → void {
+    self::result = 2;
+  }
+  static method staticMethodAndSetter2() → core::int
+    return 1;
+}
+static field dynamic result;
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static.dart:85:9: Error: Can't use 'staticMethod' because it is declared more than once.
+  Class.staticMethod();
+        ^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static.dart:86:10: Error: Can't use 'staticMethod' because it is declared more than once.
+  (Class.staticMethod)();
+         ^^^^^^^^^^^^"{dynamic}.call();
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static.dart:87:9: Error: Can't use 'staticGetter' because it is declared more than once.
+  Class.staticGetter;
+        ^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static.dart:88:22: Error: Can't assign to this.
+  Class.staticSetter = 0;
+                     ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static.dart:89:9: Error: Can't use 'staticField' because it is declared more than once.
+  Class.staticField;
+        ^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static.dart:90:21: Error: Can't assign to this.
+  Class.staticField = 0;
+                    ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static.dart:91:9: Error: Can't use 'staticDuplicateFieldAndSetter' because it is declared more than once.
+  Class.staticDuplicateFieldAndSetter;
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static.dart:92:39: Error: Can't assign to this.
+  Class.staticDuplicateFieldAndSetter = 0;
+                                      ^";
+  self::Class::staticFieldAndDuplicateSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static.dart:94:9: Error: Setter not found: 'staticFieldAndDuplicateSetter'.
+  Class.staticFieldAndDuplicateSetter = 0;
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static.dart:95:9: Error: Can't use 'staticDuplicateFieldAndDuplicateSetter' because it is declared more than once.
+  Class.staticDuplicateFieldAndDuplicateSetter;
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static.dart:96:48: Error: Can't assign to this.
+  Class.staticDuplicateFieldAndDuplicateSetter = 0;
+                                               ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static.dart:97:9: Error: Setter not found: 'staticMethodAndSetter1'.
+  Class.staticMethodAndSetter1 = 0;
+        ^^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static.dart:98:9: Error: Setter not found: 'staticMethodAndSetter2'.
+  Class.staticMethodAndSetter2 = 0;
+        ^^^^^^^^^^^^^^^^^^^^^^";
+}
+static method main() → dynamic {
+  self::result = null;
+  self::Class::staticFieldAndSetter1 = 0;
+  self::expect(null, self::result);
+  self::expect(0, self::Class::staticFieldAndSetter1);
+  self::result = null;
+  self::Class::staticFieldAndSetter2 = 0;
+  self::expect(null, self::result);
+  self::expect(0, self::Class::staticFieldAndSetter2);
+  self::result = null;
+  self::Class::staticLateFinalFieldAndSetter1 = 0;
+  self::expect(null, self::result);
+  self::expect(0, self::Class::staticLateFinalFieldAndSetter1);
+  self::result = null;
+  self::Class::staticLateFinalFieldAndSetter2 = 0;
+  self::expect(null, self::result);
+  self::expect(0, self::Class::staticLateFinalFieldAndSetter2);
+  self::expect(1, self::Class::staticMethodAndSetter1());
+  self::expect(1, self::Class::staticMethodAndSetter2());
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print(e);
+    return;
+  }
+  throw "Expected exception.";
+}
diff --git a/pkg/front_end/testcases/nnbd/duplicates_static_extension.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/duplicates_static_extension.dart.weak.modular.expect
new file mode 100644
index 0000000..925247a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/duplicates_static_extension.dart.weak.modular.expect
@@ -0,0 +1,310 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:9:14: Error: 'staticMethod' is already declared in this scope.
+//   static int staticMethod() => 2;
+//              ^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:8:14: Context: Previous declaration of 'staticMethod'.
+//   static int staticMethod() => 1;
+//              ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:12:18: Error: 'staticGetter' is already declared in this scope.
+//   static int get staticGetter => 2;
+//                  ^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:11:18: Context: Previous declaration of 'staticGetter'.
+//   static int get staticGetter => 1;
+//                  ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:18:19: Error: 'staticSetter' is already declared in this scope.
+//   static void set staticSetter(value) {
+//                   ^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:14:19: Context: Previous declaration of 'staticSetter'.
+//   static void set staticSetter(value) {
+//                   ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:23:14: Error: 'staticField' is already declared in this scope.
+//   static int staticField = 2;
+//              ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:22:14: Context: Previous declaration of 'staticField'.
+//   static int staticField = 1;
+//              ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:48:20: Error: 'staticDuplicateFieldAndSetter' is already declared in this scope.
+//   static final int staticDuplicateFieldAndSetter = 2;
+//                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:47:20: Context: Previous declaration of 'staticDuplicateFieldAndSetter'.
+//   static final int staticDuplicateFieldAndSetter = 1;
+//                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:58:19: Error: 'staticFieldAndDuplicateSetter' is already declared in this scope.
+//   static void set staticFieldAndDuplicateSetter(int value) {
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:54:19: Context: Previous declaration of 'staticFieldAndDuplicateSetter'.
+//   static void set staticFieldAndDuplicateSetter(int value) {
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:63:20: Error: 'staticDuplicateFieldAndDuplicateSetter' is already declared in this scope.
+//   static final int staticDuplicateFieldAndDuplicateSetter = 2;
+//                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:62:20: Context: Previous declaration of 'staticDuplicateFieldAndDuplicateSetter'.
+//   static final int staticDuplicateFieldAndDuplicateSetter = 1;
+//                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:68:19: Error: 'staticDuplicateFieldAndDuplicateSetter' is already declared in this scope.
+//   static void set staticDuplicateFieldAndDuplicateSetter(int value) {
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:64:19: Context: Previous declaration of 'staticDuplicateFieldAndDuplicateSetter'.
+//   static void set staticDuplicateFieldAndDuplicateSetter(int value) {
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:26:19: Error: Conflicts with the implicit setter of the field 'staticFieldAndSetter1'.
+//   static void set staticFieldAndSetter1(int value) {
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:25:14: Error: Conflicts with setter 'staticFieldAndSetter1'.
+//   static int staticFieldAndSetter1 = 1;
+//              ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:30:19: Error: Conflicts with the implicit setter of the field 'staticFieldAndSetter2'.
+//   static void set staticFieldAndSetter2(int value) {
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:34:14: Error: Conflicts with setter 'staticFieldAndSetter2'.
+//   static int staticFieldAndSetter2 = 1;
+//              ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:37:19: Error: Conflicts with the implicit setter of the field 'staticLateFinalFieldAndSetter1'.
+//   static void set staticLateFinalFieldAndSetter1(int value) {
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:36:25: Error: Conflicts with setter 'staticLateFinalFieldAndSetter1'.
+//   static late final int staticLateFinalFieldAndSetter1;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:41:19: Error: Conflicts with the implicit setter of the field 'staticLateFinalFieldAndSetter2'.
+//   static void set staticLateFinalFieldAndSetter2(int value) {
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:45:25: Error: Conflicts with setter 'staticLateFinalFieldAndSetter2'.
+//   static late final int staticLateFinalFieldAndSetter2;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:73:19: Error: Conflicts with member 'staticMethodAndSetter1'.
+//   static void set staticMethodAndSetter1(int value) {
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:72:14: Error: Conflicts with setter 'staticMethodAndSetter1'.
+//   static int staticMethodAndSetter1() => 1;
+//              ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:77:19: Error: Conflicts with member 'staticMethodAndSetter2'.
+//   static void set staticMethodAndSetter2(int value) {
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:81:14: Error: Conflicts with setter 'staticMethodAndSetter2'.
+//   static int staticMethodAndSetter2() => 1;
+//              ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:85:13: Error: Can't use 'staticMethod' because it is declared more than once.
+//   Extension.staticMethod();
+//             ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:86:14: Error: Can't use 'staticMethod' because it is declared more than once.
+//   (Extension.staticMethod)();
+//              ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:87:13: Error: Can't use 'staticGetter' because it is declared more than once.
+//   Extension.staticGetter;
+//             ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:88:13: Error: Can't use 'staticSetter' because it is declared more than once.
+//   Extension.staticSetter = 0;
+//             ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:88:26: Error: Can't assign to this.
+//   Extension.staticSetter = 0;
+//                          ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:89:13: Error: Can't use 'staticField' because it is declared more than once.
+//   Extension.staticField;
+//             ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:90:13: Error: Can't use 'staticField' because it is declared more than once.
+//   Extension.staticField = 0;
+//             ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:90:25: Error: Can't assign to this.
+//   Extension.staticField = 0;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:91:13: Error: Can't use 'staticDuplicateFieldAndSetter' because it is declared more than once.
+//   Extension.staticDuplicateFieldAndSetter;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:92:13: Error: Can't use 'staticDuplicateFieldAndSetter' because it is declared more than once.
+//   Extension.staticDuplicateFieldAndSetter = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:92:43: Error: Can't assign to this.
+//   Extension.staticDuplicateFieldAndSetter = 0;
+//                                           ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:94:13: Error: Setter not found: 'staticFieldAndDuplicateSetter'.
+//   Extension.staticFieldAndDuplicateSetter = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:95:13: Error: Can't use 'staticDuplicateFieldAndDuplicateSetter' because it is declared more than once.
+//   Extension.staticDuplicateFieldAndDuplicateSetter;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:96:13: Error: Can't use 'staticDuplicateFieldAndDuplicateSetter' because it is declared more than once.
+//   Extension.staticDuplicateFieldAndDuplicateSetter = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:96:52: Error: Can't assign to this.
+//   Extension.staticDuplicateFieldAndDuplicateSetter = 0;
+//                                                    ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:97:13: Error: Setter not found: 'staticMethodAndSetter1'.
+//   Extension.staticMethodAndSetter1 = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:98:13: Error: Setter not found: 'staticMethodAndSetter2'.
+//   Extension.staticMethodAndSetter2 = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+extension Extension on core::int {
+  static method staticMethod = self::Extension|staticMethod;
+  static get staticGetter = get self::Extension|staticGetter;
+  static field staticField = self::Extension|staticField;
+  static field staticFieldAndSetter1 = self::Extension|staticFieldAndSetter1;
+  static field staticFieldAndSetter2 = self::Extension|staticFieldAndSetter2;
+  static field staticLateFinalFieldAndSetter1 = self::Extension|staticLateFinalFieldAndSetter1;
+  static field staticLateFinalFieldAndSetter2 = self::Extension|staticLateFinalFieldAndSetter2;
+  static field staticDuplicateFieldAndSetter = self::Extension|staticDuplicateFieldAndSetter;
+  static field staticFieldAndDuplicateSetter = self::Extension|staticFieldAndDuplicateSetter;
+  static field staticDuplicateFieldAndDuplicateSetter = self::Extension|staticDuplicateFieldAndDuplicateSetter;
+  static method staticMethodAndSetter1 = self::Extension|staticMethodAndSetter1;
+  static method staticMethodAndSetter2 = self::Extension|staticMethodAndSetter2;
+  static set staticSetter = set self::Extension|staticSetter;
+  static set staticDuplicateFieldAndSetter = set self::Extension|staticDuplicateFieldAndSetter;
+  static set staticFieldAndDuplicateSetter = set self::Extension|staticFieldAndDuplicateSetter;
+  static set staticDuplicateFieldAndDuplicateSetter = set self::Extension|staticDuplicateFieldAndDuplicateSetter;
+  static set staticMethodAndSetter1 = set self::Extension|staticMethodAndSetter1;
+  static set staticMethodAndSetter2 = set self::Extension|staticMethodAndSetter2;
+}
+static field dynamic result;
+static field core::int Extension|staticField;
+static field core::int Extension|staticFieldAndSetter1 = 1;
+static field core::int Extension|staticFieldAndSetter2 = 1;
+late static final [setter] field core::int Extension|staticLateFinalFieldAndSetter1;
+late static final [setter] field core::int Extension|staticLateFinalFieldAndSetter2;
+static final field core::int Extension|staticDuplicateFieldAndSetter;
+static final field core::int Extension|staticFieldAndDuplicateSetter = 1;
+static final field core::int Extension|staticDuplicateFieldAndDuplicateSetter;
+static method Extension|staticMethod() → core::int
+  return 1;
+static get Extension|staticGetter() → core::int
+  return 1;
+static set Extension|staticSetter(dynamic value) → void {
+  self::result = 1;
+}
+static set Extension|staticDuplicateFieldAndSetter(core::int value) → void {
+  self::result = 3;
+}
+static set Extension|staticFieldAndDuplicateSetter(core::int value) → void {
+  self::result = 2;
+}
+static set Extension|staticDuplicateFieldAndDuplicateSetter(core::int value) → void {
+  self::result = 3;
+}
+static method Extension|staticMethodAndSetter1() → core::int
+  return 1;
+static set Extension|staticMethodAndSetter1(core::int value) → void {
+  self::result = 2;
+}
+static set Extension|staticMethodAndSetter2(core::int value) → void {
+  self::result = 2;
+}
+static method Extension|staticMethodAndSetter2() → core::int
+  return 1;
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:85:13: Error: Can't use 'staticMethod' because it is declared more than once.
+  Extension.staticMethod();
+            ^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:86:14: Error: Can't use 'staticMethod' because it is declared more than once.
+  (Extension.staticMethod)();
+             ^^^^^^^^^^^^"{dynamic}.call();
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:87:13: Error: Can't use 'staticGetter' because it is declared more than once.
+  Extension.staticGetter;
+            ^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:88:26: Error: Can't assign to this.
+  Extension.staticSetter = 0;
+                         ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:89:13: Error: Can't use 'staticField' because it is declared more than once.
+  Extension.staticField;
+            ^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:90:25: Error: Can't assign to this.
+  Extension.staticField = 0;
+                        ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:91:13: Error: Can't use 'staticDuplicateFieldAndSetter' because it is declared more than once.
+  Extension.staticDuplicateFieldAndSetter;
+            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:92:43: Error: Can't assign to this.
+  Extension.staticDuplicateFieldAndSetter = 0;
+                                          ^";
+  self::Extension|staticFieldAndDuplicateSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:94:13: Error: Setter not found: 'staticFieldAndDuplicateSetter'.
+  Extension.staticFieldAndDuplicateSetter = 0;
+            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:95:13: Error: Can't use 'staticDuplicateFieldAndDuplicateSetter' because it is declared more than once.
+  Extension.staticDuplicateFieldAndDuplicateSetter;
+            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:96:52: Error: Can't assign to this.
+  Extension.staticDuplicateFieldAndDuplicateSetter = 0;
+                                                   ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:97:13: Error: Setter not found: 'staticMethodAndSetter1'.
+  Extension.staticMethodAndSetter1 = 0;
+            ^^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_static_extension.dart:98:13: Error: Setter not found: 'staticMethodAndSetter2'.
+  Extension.staticMethodAndSetter2 = 0;
+            ^^^^^^^^^^^^^^^^^^^^^^";
+}
+static method main() → dynamic {
+  self::result = null;
+  self::Extension|staticFieldAndSetter1 = 0;
+  self::expect(null, self::result);
+  self::expect(0, self::Extension|staticFieldAndSetter1);
+  self::result = null;
+  self::Extension|staticFieldAndSetter2 = 0;
+  self::expect(null, self::result);
+  self::expect(0, self::Extension|staticFieldAndSetter2);
+  self::result = null;
+  self::Extension|staticLateFinalFieldAndSetter1 = 0;
+  self::expect(null, self::result);
+  self::expect(0, self::Extension|staticLateFinalFieldAndSetter1);
+  self::result = null;
+  self::Extension|staticLateFinalFieldAndSetter2 = 0;
+  self::expect(null, self::result);
+  self::expect(0, self::Extension|staticLateFinalFieldAndSetter2);
+  self::expect(1, self::Extension|staticMethodAndSetter1());
+  self::expect(1, self::Extension|staticMethodAndSetter2());
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print(e);
+    return;
+  }
+  throw "Expected exception.";
+}
diff --git a/pkg/front_end/testcases/nnbd/duplicates_toplevel.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/duplicates_toplevel.dart.weak.modular.expect
new file mode 100644
index 0000000..85c4c69
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/duplicates_toplevel.dart.weak.modular.expect
@@ -0,0 +1,400 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:8:5: Error: 'topLevelMethod' is already declared in this scope.
+// int topLevelMethod() => 2;
+//     ^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:7:5: Context: Previous declaration of 'topLevelMethod'.
+// int topLevelMethod() => 1;
+//     ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:11:9: Error: 'topLevelGetter' is already declared in this scope.
+// int get topLevelGetter => 2;
+//         ^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:10:9: Context: Previous declaration of 'topLevelGetter'.
+// int get topLevelGetter => 1;
+//         ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:17:10: Error: 'topLevelSetter' is already declared in this scope.
+// void set topLevelSetter(value) {
+//          ^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:13:10: Context: Previous declaration of 'topLevelSetter'.
+// void set topLevelSetter(value) {
+//          ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:22:5: Error: 'topLevelField' is already declared in this scope.
+// int topLevelField = 2;
+//     ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:21:5: Context: Previous declaration of 'topLevelField'.
+// int topLevelField = 1;
+//     ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:47:11: Error: 'topLevelDuplicateFieldAndSetter' is already declared in this scope.
+// final int topLevelDuplicateFieldAndSetter = 2;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:46:11: Context: Previous declaration of 'topLevelDuplicateFieldAndSetter'.
+// final int topLevelDuplicateFieldAndSetter = 1;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:57:10: Error: 'topLevelFieldAndDuplicateSetter' is already declared in this scope.
+// void set topLevelFieldAndDuplicateSetter(int value) {
+//          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:53:10: Context: Previous declaration of 'topLevelFieldAndDuplicateSetter'.
+// void set topLevelFieldAndDuplicateSetter(int value) {
+//          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:62:11: Error: 'topLevelDuplicateFieldAndDuplicateSetter' is already declared in this scope.
+// final int topLevelDuplicateFieldAndDuplicateSetter = 2;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:61:11: Context: Previous declaration of 'topLevelDuplicateFieldAndDuplicateSetter'.
+// final int topLevelDuplicateFieldAndDuplicateSetter = 1;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:67:10: Error: 'topLevelDuplicateFieldAndDuplicateSetter' is already declared in this scope.
+// void set topLevelDuplicateFieldAndDuplicateSetter(int value) {
+//          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:63:10: Context: Previous declaration of 'topLevelDuplicateFieldAndDuplicateSetter'.
+// void set topLevelDuplicateFieldAndDuplicateSetter(int value) {
+//          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart: Error: 'topLevelSetter' is exported from both 'pkg/front_end/testcases/nnbd/duplicates_toplevel.dart' and 'pkg/front_end/testcases/nnbd/duplicates_toplevel.dart'.
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart: Error: 'topLevelFieldAndDuplicateSetter' is exported from both 'pkg/front_end/testcases/nnbd/duplicates_toplevel.dart' and 'pkg/front_end/testcases/nnbd/duplicates_toplevel.dart'.
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart: Error: 'topLevelDuplicateFieldAndDuplicateSetter' is exported from both 'pkg/front_end/testcases/nnbd/duplicates_toplevel.dart' and 'pkg/front_end/testcases/nnbd/duplicates_toplevel.dart'.
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:25:10: Error: Conflicts with the implicit setter of the field 'topLevelFieldAndSetter1'.
+// void set topLevelFieldAndSetter1(int value) {
+//          ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:24:5: Error: Conflicts with setter 'topLevelFieldAndSetter1'.
+// int topLevelFieldAndSetter1 = 1;
+//     ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:29:10: Error: Conflicts with the implicit setter of the field 'topLevelFieldAndSetter2'.
+// void set topLevelFieldAndSetter2(int value) {
+//          ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:33:5: Error: Conflicts with setter 'topLevelFieldAndSetter2'.
+// int topLevelFieldAndSetter2 = 1;
+//     ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:36:10: Error: Conflicts with the implicit setter of the field 'topLevelLateFinalFieldAndSetter1'.
+// void set topLevelLateFinalFieldAndSetter1(int value) {
+//          ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:35:16: Error: Conflicts with setter 'topLevelLateFinalFieldAndSetter1'.
+// late final int topLevelLateFinalFieldAndSetter1;
+//                ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:40:10: Error: Conflicts with the implicit setter of the field 'topLevelLateFinalFieldAndSetter2'.
+// void set topLevelLateFinalFieldAndSetter2(int value) {
+//          ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:44:16: Error: Conflicts with setter 'topLevelLateFinalFieldAndSetter2'.
+// late final int topLevelLateFinalFieldAndSetter2;
+//                ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:72:10: Error: Conflicts with member 'topLevelMethodAndSetter1'.
+// void set topLevelMethodAndSetter1(int value) {
+//          ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:71:5: Error: Conflicts with setter 'topLevelMethodAndSetter1'.
+// int topLevelMethodAndSetter1() => 1;
+//     ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:76:10: Error: Conflicts with member 'topLevelMethodAndSetter2'.
+// void set topLevelMethodAndSetter2(int value) {
+//          ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:80:5: Error: Conflicts with setter 'topLevelMethodAndSetter2'.
+// int topLevelMethodAndSetter2() => 1;
+//     ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:82:13: Error: Can't use 'topLevelMethod' because it is declared more than once.
+// var field = topLevelMethod;
+//             ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:84:2: Error: Can't use 'topLevelMethod' because it is declared more than once.
+// @topLevelMethod
+//  ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:84:2: Error: This can't be used as an annotation; an annotation should be a reference to a compile-time constant variable, or a call to a constant constructor.
+// @topLevelMethod
+//  ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:86:3: Error: Can't use 'topLevelMethod' because it is declared more than once.
+//   topLevelMethod();
+//   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:87:4: Error: Can't use 'topLevelMethod' because it is declared more than once.
+//   (topLevelMethod)();
+//    ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:88:7: Error: Can't use 'topLevelMethod' because it is declared more than once.
+//   if (topLevelMethod) {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:89:3: Error: Can't use 'topLevelMethod' because it is declared more than once.
+//   topLevelMethod;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:90:4: Error: Can't use 'topLevelMethod' because it is declared more than once.
+//   @topLevelMethod
+//    ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:90:4: Error: This can't be used as an annotation; an annotation should be a reference to a compile-time constant variable, or a call to a constant constructor.
+//   @topLevelMethod
+//    ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:93:24: Error: Expected ':' before this.
+//     case topLevelMethod;
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:93:10: Error: Can't use 'topLevelMethod' because it is declared more than once.
+//     case topLevelMethod;
+//          ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:95:3: Error: Can't use 'topLevelMethod' because it is declared more than once.
+//   topLevelMethod || topLevelMethod;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:95:21: Error: Can't use 'topLevelMethod' because it is declared more than once.
+//   topLevelMethod || topLevelMethod;
+//                     ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:96:3: Error: Can't use 'topLevelMethod' because it is declared more than once.
+//   topLevelMethod + 0;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:97:18: Error: '~' isn't a binary operator.
+//   topLevelMethod ~ 0;
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:98:21: Error: Can't use 'topLevelMethod' because it is declared more than once.
+//   topLevelMethod ?? topLevelMethod;
+//                     ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:98:3: Error: Can't use 'topLevelMethod' because it is declared more than once.
+//   topLevelMethod ?? topLevelMethod;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:99:3: Error: Can't use 'topLevelMethod' because it is declared more than once.
+//   topLevelMethod?.foo;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:100:3: Error: Can't use 'topLevelMethod' because it is declared more than once.
+//   topLevelMethod?.foo();
+//   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:101:3: Error: Can't use 'topLevelGetter' because it is declared more than once.
+//   topLevelGetter;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:102:18: Error: Can't assign to this.
+//   topLevelSetter = 0;
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:103:3: Error: Can't use 'topLevelField' because it is declared more than once.
+//   topLevelField;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:104:17: Error: Can't assign to this.
+//   topLevelField = 0;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:105:3: Error: Can't use 'topLevelDuplicateFieldAndSetter' because it is declared more than once.
+//   topLevelDuplicateFieldAndSetter;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:106:35: Error: Can't assign to this.
+//   topLevelDuplicateFieldAndSetter = 0;
+//                                   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:108:3: Error: Setter not found: 'topLevelFieldAndDuplicateSetter'.
+//   topLevelFieldAndDuplicateSetter = 0;
+//   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:109:3: Error: Can't use 'topLevelDuplicateFieldAndDuplicateSetter' because it is declared more than once.
+//   topLevelDuplicateFieldAndDuplicateSetter;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:110:44: Error: Can't assign to this.
+//   topLevelDuplicateFieldAndDuplicateSetter = 0;
+//                                            ^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:111:3: Error: Setter not found: 'topLevelMethodAndSetter1'.
+//   topLevelMethodAndSetter1 = 0;
+//   ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:112:3: Error: Setter not found: 'topLevelMethodAndSetter2'.
+//   topLevelMethodAndSetter2 = 0;
+//   ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static field dynamic result;
+static field core::int topLevelField;
+static field core::int topLevelFieldAndSetter1 = 1;
+static field core::int topLevelFieldAndSetter2 = 1;
+late static final [setter] field core::int topLevelLateFinalFieldAndSetter1;
+late static final [setter] field core::int topLevelLateFinalFieldAndSetter2;
+static final field core::int topLevelDuplicateFieldAndSetter;
+static final field core::int topLevelFieldAndDuplicateSetter = 1;
+static final field core::int topLevelDuplicateFieldAndDuplicateSetter;
+static field invalid-type field = invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:82:13: Error: Can't use 'topLevelMethod' because it is declared more than once.
+var field = topLevelMethod;
+            ^";
+static const field dynamic _exports# = #C1 /*isLegacy*/;
+static method topLevelMethod() → core::int
+  return 1;
+static get topLevelGetter() → core::int
+  return 1;
+static set topLevelSetter(dynamic value) → void {
+  self::result = 1;
+}
+static set topLevelDuplicateFieldAndSetter(core::int value) → void {
+  self::result = 3;
+}
+static set topLevelFieldAndDuplicateSetter(core::int value) → void {
+  self::result = 2;
+}
+static set topLevelDuplicateFieldAndDuplicateSetter(core::int value) → void {
+  self::result = 3;
+}
+static method topLevelMethodAndSetter1() → core::int
+  return 1;
+static set topLevelMethodAndSetter1(core::int value) → void {
+  self::result = 2;
+}
+static set topLevelMethodAndSetter2(core::int value) → void {
+  self::result = 2;
+}
+static method topLevelMethodAndSetter2() → core::int
+  return 1;
+@invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:84:2: Error: This can't be used as an annotation; an annotation should be a reference to a compile-time constant variable, or a call to a constant constructor.
+@topLevelMethod
+ ^"
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:86:3: Error: Can't use 'topLevelMethod' because it is declared more than once.
+  topLevelMethod();
+  ^"{dynamic}.call();
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:87:4: Error: Can't use 'topLevelMethod' because it is declared more than once.
+  (topLevelMethod)();
+   ^"{dynamic}.call();
+  if(invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:88:7: Error: Can't use 'topLevelMethod' because it is declared more than once.
+  if (topLevelMethod) {}
+      ^") {
+  }
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:89:3: Error: Can't use 'topLevelMethod' because it is declared more than once.
+  topLevelMethod;
+  ^";
+  @invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:90:4: Error: This can't be used as an annotation; an annotation should be a reference to a compile-time constant variable, or a call to a constant constructor.
+  @topLevelMethod
+   ^" dynamic foo;
+  switch(null) {
+    #L1:
+    case invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:93:10: Error: Can't use 'topLevelMethod' because it is declared more than once.
+    case topLevelMethod;
+         ^":
+      {
+        ;
+      }
+  }
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:95:3: Error: Can't use 'topLevelMethod' because it is declared more than once.
+  topLevelMethod || topLevelMethod;
+  ^" || invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:95:21: Error: Can't use 'topLevelMethod' because it is declared more than once.
+  topLevelMethod || topLevelMethod;
+                    ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:96:3: Error: Can't use 'topLevelMethod' because it is declared more than once.
+  topLevelMethod + 0;
+  ^"{<invalid>}.+(0);
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:97:18: Error: '~' isn't a binary operator.
+  topLevelMethod ~ 0;
+                 ^";
+  let final invalid-type #t1 = invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:98:3: Error: Can't use 'topLevelMethod' because it is declared more than once.
+  topLevelMethod ?? topLevelMethod;
+  ^" in #t1 == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:98:21: Error: Can't use 'topLevelMethod' because it is declared more than once.
+  topLevelMethod ?? topLevelMethod;
+                    ^" : #t1;
+  let final invalid-type #t2 = invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:99:3: Error: Can't use 'topLevelMethod' because it is declared more than once.
+  topLevelMethod?.foo;
+  ^" in #t2 == null ?{invalid-type} null : #t2{<invalid>}.foo;
+  let final invalid-type #t3 = invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:100:3: Error: Can't use 'topLevelMethod' because it is declared more than once.
+  topLevelMethod?.foo();
+  ^" in #t3 == null ?{dynamic} null : #t3{dynamic}.foo();
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:101:3: Error: Can't use 'topLevelGetter' because it is declared more than once.
+  topLevelGetter;
+  ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:102:18: Error: Can't assign to this.
+  topLevelSetter = 0;
+                 ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:103:3: Error: Can't use 'topLevelField' because it is declared more than once.
+  topLevelField;
+  ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:104:17: Error: Can't assign to this.
+  topLevelField = 0;
+                ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:105:3: Error: Can't use 'topLevelDuplicateFieldAndSetter' because it is declared more than once.
+  topLevelDuplicateFieldAndSetter;
+  ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:106:35: Error: Can't assign to this.
+  topLevelDuplicateFieldAndSetter = 0;
+                                  ^";
+  self::topLevelFieldAndDuplicateSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:108:3: Error: Setter not found: 'topLevelFieldAndDuplicateSetter'.
+  topLevelFieldAndDuplicateSetter = 0;
+  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:109:3: Error: Can't use 'topLevelDuplicateFieldAndDuplicateSetter' because it is declared more than once.
+  topLevelDuplicateFieldAndDuplicateSetter;
+  ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:110:44: Error: Can't assign to this.
+  topLevelDuplicateFieldAndDuplicateSetter = 0;
+                                           ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:111:3: Error: Setter not found: 'topLevelMethodAndSetter1'.
+  topLevelMethodAndSetter1 = 0;
+  ^^^^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/duplicates_toplevel.dart:112:3: Error: Setter not found: 'topLevelMethodAndSetter2'.
+  topLevelMethodAndSetter2 = 0;
+  ^^^^^^^^^^^^^^^^^^^^^^^^";
+}
+static method main() → dynamic {
+  self::result = null;
+  self::topLevelFieldAndSetter1 = 0;
+  self::expect(null, self::result);
+  self::expect(0, self::topLevelFieldAndSetter1);
+  self::result = null;
+  self::topLevelFieldAndSetter2 = 0;
+  self::expect(null, self::result);
+  self::expect(0, self::topLevelFieldAndSetter2);
+  self::result = null;
+  self::topLevelLateFinalFieldAndSetter1 = 0;
+  self::expect(null, self::result);
+  self::expect(0, self::topLevelLateFinalFieldAndSetter1);
+  self::result = null;
+  self::topLevelLateFinalFieldAndSetter2 = 0;
+  self::expect(null, self::result);
+  self::expect(0, self::topLevelLateFinalFieldAndSetter2);
+  self::expect(1, self::topLevelMethodAndSetter1());
+  self::expect(1, self::topLevelMethodAndSetter2());
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f) → dynamic {
+  try {
+    f(){() → dynamic};
+  }
+  on core::Object catch(final core::Object e) {
+    core::print(e);
+    return;
+  }
+  throw "Expected exception.";
+}
+
+constants  {
+  #C1 = "{\"topLevelSetter\":\"'topLevelSetter' is exported from both 'pkg/front_end/testcases/nnbd/duplicates_toplevel.dart' and 'pkg/front_end/testcases/nnbd/duplicates_toplevel.dart'.\",\"topLevelFieldAndDuplicateSetter\":\"'topLevelFieldAndDuplicateSetter' is exported from both 'pkg/front_end/testcases/nnbd/duplicates_toplevel.dart' and 'pkg/front_end/testcases/nnbd/duplicates_toplevel.dart'.\",\"topLevelDuplicateFieldAndDuplicateSetter\":\"'topLevelDuplicateFieldAndDuplicateSetter' is exported from both 'pkg/front_end/testcases/nnbd/duplicates_toplevel.dart' and 'pkg/front_end/testcases/nnbd/duplicates_toplevel.dart'.\"}"
+}
diff --git a/pkg/front_end/testcases/nnbd/dynamic_object_call.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/dynamic_object_call.dart.weak.modular.expect
new file mode 100644
index 0000000..0d1dd3b
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/dynamic_object_call.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/dynamic_object_call.dart:21:22: Error: 'hashCode' isn't a function or method and can't be invoked.
+//   var v5 = c.hashCode();
+//                      ^^^^...
+//
+// pkg/front_end/testcases/nnbd/dynamic_object_call.dart:23:27: Error: The argument type 'String' can't be assigned to the parameter type 'Invocation'.
+//  - 'Invocation' is from 'dart:core'.
+//   var v6 = c.noSuchMethod("foo");
+//                           ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  @#C1
+  method noSuchMethod(core::Object o, {core::String foo = #C2}) → dynamic
+    return 42;
+  @#C1
+  method toString({core::String foo = #C2}) → core::String
+    return "foo";
+}
+static method main() → dynamic {}
+static method test() → dynamic {
+  dynamic c = new self::Class::•();
+  core::String v1 = c.{core::Object::toString}(){() → core::String};
+  dynamic v2 = c{dynamic}.toString(foo: 42);
+  () → core::String v3 = c.{core::Object::toString}{() → core::String};
+  core::int v4 = c.{core::Object::hashCode}{core::int};
+  dynamic v5 = invalid-expression "pkg/front_end/testcases/nnbd/dynamic_object_call.dart:21:22: Error: 'hashCode' isn't a function or method and can't be invoked.
+  var v5 = c.hashCode();
+                     ^^^^..." in c.{core::Object::hashCode}{core::int}{<unresolved>}.call();
+  dynamic v6 = c.{core::Object::noSuchMethod}(invalid-expression "pkg/front_end/testcases/nnbd/dynamic_object_call.dart:23:27: Error: The argument type 'String' can't be assigned to the parameter type 'Invocation'.
+ - 'Invocation' is from 'dart:core'.
+  var v6 = c.noSuchMethod(\"foo\");
+                          ^" in "foo" as{TypeError,ForNonNullableByDefault} core::Invocation){(core::Invocation) → dynamic};
+  dynamic v7 = c{dynamic}.noSuchMethod("foo", foo: 42);
+  (core::Invocation) → dynamic v8 = c.{core::Object::noSuchMethod}{(core::Invocation) → dynamic};
+}
+
+constants  {
+  #C1 = core::_Override {}
+  #C2 = ""
+}
diff --git a/pkg/front_end/testcases/nnbd/export_main_declaration.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/export_main_declaration.dart.weak.modular.expect
new file mode 100644
index 0000000..c4ad76f
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/export_main_declaration.dart.weak.modular.expect
@@ -0,0 +1,416 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "main_declaration.dart" as mai;
+additionalExports = (mai::main)
+
+import "org-dartlang-testcase:///export_main_declaration_class_lib.dart" as class_lib;
+import "org-dartlang-testcase:///export_main_declaration_extension_lib.dart" as extension_lib;
+import "org-dartlang-testcase:///export_main_declaration_field_lib.dart" as field_lib;
+import "org-dartlang-testcase:///export_main_declaration_getter_lib.dart" as getter_lib;
+import "org-dartlang-testcase:///export_main_declaration_method_extra_optional_parameters_lib.dart" as method_extra_optional_parameters_lib;
+import "org-dartlang-testcase:///export_main_declaration_method_named_parameters_lib.dart" as method_named_parameters_lib;
+import "org-dartlang-testcase:///export_main_declaration_method_one_optional_parameter_lib.dart" as method_one_optional_parameter_lib;
+import "org-dartlang-testcase:///export_main_declaration_method_one_parameter_lib.dart" as method_one_parameter_lib;
+import "org-dartlang-testcase:///export_main_declaration_method_one_required_optional_lib.dart" as method_one_required_optional_lib;
+import "org-dartlang-testcase:///export_main_declaration_method_required_named_parameters_lib.dart" as method_required_named_parameters_lib;
+import "org-dartlang-testcase:///export_main_declaration_method_too_many_parameters_lib.dart" as method_too_many_parameters_lib;
+import "org-dartlang-testcase:///export_main_declaration_method_two_optional_parameters_lib.dart" as method_two_optional_parameters_lib;
+import "org-dartlang-testcase:///export_main_declaration_method_two_parameters_lib.dart" as method_two_parameters_lib;
+import "org-dartlang-testcase:///export_main_declaration_method_wrong_parameter_type_lib.dart" as method_wrong_parameter_type_lib;
+import "org-dartlang-testcase:///export_main_declaration_setter_lib.dart" as setter_lib;
+import "org-dartlang-testcase:///export_main_declaration_typedef_lib.dart" as typedef_lib;
+export "org-dartlang-testcase:///main_declaration.dart";
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/export_main_declaration_class_lib.dart: Error: The exported 'main' declaration must be a function declaration.
+// pkg/front_end/testcases/nnbd/main_declaration_class_lib.dart:5:7: Context: This is exported 'main' declaration.
+// class main /* error */ {}
+//       ^
+//
+import self as self2;
+import "main_declaration_class_lib.dart" as mai2;
+additionalExports = (mai2::main)
+
+export "org-dartlang-testcase:///main_declaration_class_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/export_main_declaration_extension_lib.dart: Error: The exported 'main' declaration must be a function declaration.
+// pkg/front_end/testcases/nnbd/main_declaration_extension_lib.dart:5:11: Context: This is exported 'main' declaration.
+// extension main /* error */ on Object {}
+//           ^
+//
+import self as self3;
+import "main_declaration_extension_lib.dart" as mai3;
+additionalExports = (mai3::main)
+
+export "org-dartlang-testcase:///main_declaration_extension_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/export_main_declaration_field_lib.dart: Error: The exported 'main' declaration must be a function declaration.
+// pkg/front_end/testcases/nnbd/main_declaration_field_lib.dart:5:17: Context: This is exported 'main' declaration.
+// void Function() main /* error */ = () {};
+//                 ^^^^
+//
+import self as self4;
+import "main_declaration_field_lib.dart" as mai4;
+additionalExports = (mai4::main,
+  mai4::main)
+
+export "org-dartlang-testcase:///main_declaration_field_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/export_main_declaration_getter_lib.dart: Error: The exported 'main' declaration must be a function declaration.
+// pkg/front_end/testcases/nnbd/main_declaration_getter_lib.dart:5:21: Context: This is exported 'main' declaration.
+// void Function() get main /* error */ => () {};
+//                     ^^^^
+//
+import self as self5;
+import "main_declaration_getter_lib.dart" as mai5;
+additionalExports = (mai5::main)
+
+export "org-dartlang-testcase:///main_declaration_getter_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+import self as self6;
+import "main_declaration_method_extra_optional_parameters_lib.dart" as mai6;
+additionalExports = (mai6::main)
+
+export "org-dartlang-testcase:///main_declaration_method_extra_optional_parameters_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+import self as self7;
+import "main_declaration_method_named_parameters_lib.dart" as mai7;
+additionalExports = (mai7::main)
+
+export "org-dartlang-testcase:///main_declaration_method_named_parameters_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+import self as self8;
+import "main_declaration_method_one_optional_parameter_lib.dart" as mai8;
+additionalExports = (mai8::main)
+
+export "org-dartlang-testcase:///main_declaration_method_one_optional_parameter_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+import self as self9;
+import "main_declaration_method_one_parameter_lib.dart" as mai9;
+additionalExports = (mai9::main)
+
+export "org-dartlang-testcase:///main_declaration_method_one_parameter_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+import self as self10;
+import "main_declaration_method_one_required_optional_lib.dart" as mai10;
+additionalExports = (mai10::main)
+
+export "org-dartlang-testcase:///main_declaration_method_one_required_optional_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/export_main_declaration_method_required_named_parameters_lib.dart: Error: The exported 'main' method cannot have required named parameters.
+// pkg/front_end/testcases/nnbd/main_declaration_method_required_named_parameters_lib.dart:5:6: Context: This is exported 'main' declaration.
+// void main({required List<String> args}) /* error */ {}
+//      ^^^^
+//
+import self as self11;
+import "main_declaration_method_required_named_parameters_lib.dart" as mai11;
+additionalExports = (mai11::main)
+
+export "org-dartlang-testcase:///main_declaration_method_required_named_parameters_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/export_main_declaration_method_too_many_parameters_lib.dart: Error: The exported 'main' method must have at most 2 required parameters.
+// pkg/front_end/testcases/nnbd/main_declaration_method_too_many_parameters_lib.dart:5:6: Context: This is exported 'main' declaration.
+// void main(List<String> args, a, b) /* error */ {}
+//      ^^^^
+//
+import self as self12;
+import "main_declaration_method_too_many_parameters_lib.dart" as mai12;
+additionalExports = (mai12::main)
+
+export "org-dartlang-testcase:///main_declaration_method_too_many_parameters_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+import self as self13;
+import "main_declaration_method_two_optional_parameters_lib.dart" as mai13;
+additionalExports = (mai13::main)
+
+export "org-dartlang-testcase:///main_declaration_method_two_optional_parameters_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+import self as self14;
+import "main_declaration_method_two_parameters_lib.dart" as mai14;
+additionalExports = (mai14::main)
+
+export "org-dartlang-testcase:///main_declaration_method_two_parameters_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/export_main_declaration_method_wrong_parameter_type_lib.dart: Error: The type 'Set<String>' of the first parameter of the exported 'main' method is not a supertype of 'List<String>'.
+//  - 'Set' is from 'dart:core'.
+//  - 'List' is from 'dart:core'.
+// pkg/front_end/testcases/nnbd/main_declaration_method_wrong_parameter_type_lib.dart:5:6: Context: This is exported 'main' declaration.
+// void main(Set<String> args) /* error */ {}
+//      ^^^^
+//
+import self as self15;
+import "main_declaration_method_wrong_parameter_type_lib.dart" as mai15;
+additionalExports = (mai15::main)
+
+export "org-dartlang-testcase:///main_declaration_method_wrong_parameter_type_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/export_main_declaration_setter_lib.dart: Error: The exported 'main' declaration must be a function declaration.
+// pkg/front_end/testcases/nnbd/main_declaration_setter_lib.dart:5:10: Context: This is exported 'main' declaration.
+// void set main(void Function() f) /* error */ {}
+//          ^^^^
+//
+import self as self16;
+import "main_declaration_setter_lib.dart" as mai16;
+additionalExports = (mai16::main)
+
+export "org-dartlang-testcase:///main_declaration_setter_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/export_main_declaration_typedef_lib.dart: Error: The exported 'main' declaration must be a function declaration.
+// pkg/front_end/testcases/nnbd/main_declaration_typedef_lib.dart:5:9: Context: This is exported 'main' declaration.
+// typedef main /* error */ = void Function();
+//         ^
+//
+import self as self17;
+import "main_declaration_typedef_lib.dart" as mai17;
+additionalExports = (mai17::main)
+
+export "org-dartlang-testcase:///main_declaration_typedef_lib.dart";
+
+
+library /*isNonNullableByDefault*/;
+import self as mai;
+
+import "org-dartlang-testcase:///main_declaration_class_lib.dart" as class_lib;
+import "org-dartlang-testcase:///main_declaration_extension_lib.dart" as extension_lib;
+import "org-dartlang-testcase:///main_declaration_field_lib.dart" as field_lib;
+import "org-dartlang-testcase:///main_declaration_getter_lib.dart" as getter_lib;
+import "org-dartlang-testcase:///main_declaration_method_extra_optional_parameters_lib.dart" as method_extra_optional_parameters_lib;
+import "org-dartlang-testcase:///main_declaration_method_named_parameters_lib.dart" as method_named_parameters_lib;
+import "org-dartlang-testcase:///main_declaration_method_one_optional_parameter_lib.dart" as method_one_optional_parameter_lib;
+import "org-dartlang-testcase:///main_declaration_method_one_parameter_lib.dart" as method_one_parameter_lib;
+import "org-dartlang-testcase:///main_declaration_method_one_required_optional_lib.dart" as method_one_required_optional_lib;
+import "org-dartlang-testcase:///main_declaration_method_required_named_parameters_lib.dart" as method_required_named_parameters_lib;
+import "org-dartlang-testcase:///main_declaration_method_too_many_parameters_lib.dart" as method_too_many_parameters_lib;
+import "org-dartlang-testcase:///main_declaration_method_two_optional_parameters_lib.dart" as method_two_optional_parameters_lib;
+import "org-dartlang-testcase:///main_declaration_method_two_parameters_lib.dart" as method_two_parameters_lib;
+import "org-dartlang-testcase:///main_declaration_method_wrong_parameter_type_lib.dart" as method_wrong_parameter_type_lib;
+import "org-dartlang-testcase:///main_declaration_setter_lib.dart" as setter_lib;
+import "org-dartlang-testcase:///main_declaration_typedef_lib.dart" as typedef_lib;
+
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_class_lib.dart:5:7: Error: The 'main' declaration must be a function declaration.
+// class main /* error */ {}
+//       ^
+//
+import self as mai2;
+import "dart:core" as core;
+
+class main extends core::Object {
+  synthetic constructor •() → mai2::main
+    : super core::Object::•()
+    ;
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_extension_lib.dart:5:11: Error: The 'main' declaration must be a function declaration.
+// extension main /* error */ on Object {}
+//           ^
+//
+import self as mai3;
+import "dart:core" as core;
+
+extension main on core::Object {
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_field_lib.dart:5:17: Error: The 'main' declaration must be a function declaration.
+// void Function() main /* error */ = () {};
+//                 ^^^^
+//
+import self as mai4;
+
+static field () → void main = () → void {};
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_getter_lib.dart:5:21: Error: The 'main' declaration must be a function declaration.
+// void Function() get main /* error */ => () {};
+//                     ^^^^
+//
+import self as mai5;
+
+static get main() → () → void
+  return () → void {};
+
+library /*isNonNullableByDefault*/;
+import self as mai6;
+import "dart:core" as core;
+
+static method main(core::List<core::String> args, dynamic other, [dynamic extra = #C1]) → void {}
+
+library /*isNonNullableByDefault*/;
+import self as mai7;
+import "dart:core" as core;
+
+static method main({core::List<core::String> args = #C2}) → void {}
+
+library /*isNonNullableByDefault*/;
+import self as mai8;
+import "dart:core" as core;
+
+static method main([core::List<core::String>? args = #C1]) → void {}
+
+library /*isNonNullableByDefault*/;
+import self as mai9;
+import "dart:core" as core;
+
+static method main(core::List<core::String> args) → void {}
+
+library /*isNonNullableByDefault*/;
+import self as mai10;
+import "dart:core" as core;
+
+static method main(core::List<core::String> args, [dynamic other = #C1]) → void {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_method_required_named_parameters_lib.dart:5:6: Error: The 'main' method cannot have required named parameters.
+// void main({required List<String> args}) /* error */ {}
+//      ^^^^
+//
+import self as mai11;
+import "dart:core" as core;
+
+static method main({required core::List<core::String> args = #C1}) → void {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_method_too_many_parameters_lib.dart:5:6: Error: The 'main' method must have at most 2 required parameters.
+// void main(List<String> args, a, b) /* error */ {}
+//      ^^^^
+//
+import self as mai12;
+import "dart:core" as core;
+
+static method main(core::List<core::String> args, dynamic a, dynamic b) → void {}
+
+library /*isNonNullableByDefault*/;
+import self as mai13;
+import "dart:core" as core;
+
+static method main([core::List<core::String> args = #C2, dynamic other = #C1]) → void {}
+
+library /*isNonNullableByDefault*/;
+import self as mai14;
+import "dart:core" as core;
+
+static method main(core::List<core::String> args, dynamic other) → void {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_method_wrong_parameter_type_lib.dart:5:6: Error: The type 'Set<String>' of the first parameter of the 'main' method is not a supertype of 'List<String>'.
+//  - 'Set' is from 'dart:core'.
+//  - 'List' is from 'dart:core'.
+// void main(Set<String> args) /* error */ {}
+//      ^^^^
+//
+import self as mai15;
+import "dart:core" as core;
+
+static method main(core::Set<core::String> args) → void {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_setter_lib.dart:5:10: Error: The 'main' declaration must be a function declaration.
+// void set main(void Function() f) /* error */ {}
+//          ^^^^
+//
+import self as mai16;
+
+static set main(() → void f) → void {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_typedef_lib.dart:5:9: Error: The 'main' declaration must be a function declaration.
+// typedef main /* error */ = void Function();
+//         ^
+//
+import self as mai17;
+
+typedef main = () → void;
+
+constants  {
+  #C1 = null
+  #C2 = <core::String*>[]
+}
diff --git a/pkg/front_end/testcases/nnbd/extension_bounds.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/extension_bounds.dart.weak.modular.expect
new file mode 100644
index 0000000..71679c9
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/extension_bounds.dart.weak.modular.expect
@@ -0,0 +1,140 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+extension Extension1<T extends core::Object> on T {
+  method method1 = self::Extension1|method1;
+  tearoff method1 = self::Extension1|get#method1;
+  method method2 = self::Extension1|method2;
+  tearoff method2 = self::Extension1|get#method2;
+  method method3 = self::Extension1|method3;
+  tearoff method3 = self::Extension1|get#method3;
+  method method4 = self::Extension1|method4;
+  tearoff method4 = self::Extension1|get#method4;
+  method method5 = self::Extension1|method5;
+  tearoff method5 = self::Extension1|get#method5;
+}
+extension Extension2<T extends core::String> on T {
+  method method1 = self::Extension2|method1;
+  tearoff method1 = self::Extension2|get#method1;
+  method method2 = self::Extension2|method2;
+  tearoff method2 = self::Extension2|get#method2;
+  method method3 = self::Extension2|method3;
+  tearoff method3 = self::Extension2|get#method3;
+  method method4 = self::Extension2|method4;
+  tearoff method4 = self::Extension2|get#method4;
+  method method5 = self::Extension2|method5;
+  tearoff method5 = self::Extension2|get#method5;
+}
+extension Extension3<T extends dynamic> on T% {
+  method method1 = self::Extension3|method1;
+  tearoff method1 = self::Extension3|get#method1;
+  method method2 = self::Extension3|method2;
+  tearoff method2 = self::Extension3|get#method2;
+  method method3 = self::Extension3|method3;
+  tearoff method3 = self::Extension3|get#method3;
+  method method4 = self::Extension3|method4;
+  tearoff method4 = self::Extension3|get#method4;
+  method method5 = self::Extension3|method5;
+  tearoff method5 = self::Extension3|get#method5;
+}
+extension Extension4<T extends core::Object? = dynamic> on T% {
+  method method1 = self::Extension4|method1;
+  tearoff method1 = self::Extension4|get#method1;
+  method method2 = self::Extension4|method2;
+  tearoff method2 = self::Extension4|get#method2;
+  method method3 = self::Extension4|method3;
+  tearoff method3 = self::Extension4|get#method3;
+  method method4 = self::Extension4|method4;
+  tearoff method4 = self::Extension4|get#method4;
+  method method5 = self::Extension4|method5;
+  tearoff method5 = self::Extension4|get#method5;
+}
+extension Extension5<T extends core::Object?> on T% {
+  method method1 = self::Extension5|method1;
+  tearoff method1 = self::Extension5|get#method1;
+  method method2 = self::Extension5|method2;
+  tearoff method2 = self::Extension5|get#method2;
+  method method3 = self::Extension5|method3;
+  tearoff method3 = self::Extension5|get#method3;
+  method method4 = self::Extension5|method4;
+  tearoff method4 = self::Extension5|get#method4;
+  method method5 = self::Extension5|method5;
+  tearoff method5 = self::Extension5|get#method5;
+}
+static method Extension1|method1<T extends core::Object, S extends core::Object>(lowered final self::Extension1|method1::T #this) → dynamic {}
+static method Extension1|get#method1<T extends core::Object>(lowered final self::Extension1|get#method1::T #this) → <S extends core::Object>() → dynamic
+  return <S extends core::Object>() → dynamic => self::Extension1|method1<self::Extension1|get#method1::T, S>(#this);
+static method Extension1|method2<T extends core::Object, S extends core::String>(lowered final self::Extension1|method2::T #this) → dynamic {}
+static method Extension1|get#method2<T extends core::Object>(lowered final self::Extension1|get#method2::T #this) → <S extends core::String>() → dynamic
+  return <S extends core::String>() → dynamic => self::Extension1|method2<self::Extension1|get#method2::T, S>(#this);
+static method Extension1|method3<T extends core::Object, S extends dynamic>(lowered final self::Extension1|method3::T #this) → dynamic {}
+static method Extension1|get#method3<T extends core::Object>(lowered final self::Extension1|get#method3::T #this) → <S extends dynamic>() → dynamic
+  return <S extends dynamic>() → dynamic => self::Extension1|method3<self::Extension1|get#method3::T, S%>(#this);
+static method Extension1|method4<T extends core::Object, S extends core::Object? = dynamic>(lowered final self::Extension1|method4::T #this) → dynamic {}
+static method Extension1|get#method4<T extends core::Object>(lowered final self::Extension1|get#method4::T #this) → <S extends core::Object? = dynamic>() → dynamic
+  return <S extends core::Object? = dynamic>() → dynamic => self::Extension1|method4<self::Extension1|get#method4::T, S%>(#this);
+static method Extension1|method5<T extends core::Object, S extends core::Object?>(lowered final self::Extension1|method5::T #this) → dynamic {}
+static method Extension1|get#method5<T extends core::Object>(lowered final self::Extension1|get#method5::T #this) → <S extends core::Object?>() → dynamic
+  return <S extends core::Object?>() → dynamic => self::Extension1|method5<self::Extension1|get#method5::T, S%>(#this);
+static method Extension2|method1<T extends core::String, S extends core::Object>(lowered final self::Extension2|method1::T #this) → dynamic {}
+static method Extension2|get#method1<T extends core::String>(lowered final self::Extension2|get#method1::T #this) → <S extends core::Object>() → dynamic
+  return <S extends core::Object>() → dynamic => self::Extension2|method1<self::Extension2|get#method1::T, S>(#this);
+static method Extension2|method2<T extends core::String, S extends core::String>(lowered final self::Extension2|method2::T #this) → dynamic {}
+static method Extension2|get#method2<T extends core::String>(lowered final self::Extension2|get#method2::T #this) → <S extends core::String>() → dynamic
+  return <S extends core::String>() → dynamic => self::Extension2|method2<self::Extension2|get#method2::T, S>(#this);
+static method Extension2|method3<T extends core::String, S extends dynamic>(lowered final self::Extension2|method3::T #this) → dynamic {}
+static method Extension2|get#method3<T extends core::String>(lowered final self::Extension2|get#method3::T #this) → <S extends dynamic>() → dynamic
+  return <S extends dynamic>() → dynamic => self::Extension2|method3<self::Extension2|get#method3::T, S%>(#this);
+static method Extension2|get#method4<T extends core::String>(lowered final self::Extension2|get#method4::T #this) → <S extends core::Object? = dynamic>() → dynamic
+  return <S extends core::Object? = dynamic>() → dynamic => self::Extension2|method4<self::Extension2|get#method4::T, S%>(#this);
+static method Extension2|method4<T extends core::String, S extends core::Object? = dynamic>(lowered final self::Extension2|method4::T #this) → dynamic {}
+static method Extension2|method5<T extends core::String, S extends core::Object?>(lowered final self::Extension2|method5::T #this) → dynamic {}
+static method Extension2|get#method5<T extends core::String>(lowered final self::Extension2|get#method5::T #this) → <S extends core::Object?>() → dynamic
+  return <S extends core::Object?>() → dynamic => self::Extension2|method5<self::Extension2|get#method5::T, S%>(#this);
+static method Extension3|method1<T extends dynamic, S extends core::Object>(lowered final self::Extension3|method1::T% #this) → dynamic {}
+static method Extension3|get#method1<T extends dynamic>(lowered final self::Extension3|get#method1::T% #this) → <S extends core::Object>() → dynamic
+  return <S extends core::Object>() → dynamic => self::Extension3|method1<self::Extension3|get#method1::T%, S>(#this);
+static method Extension3|method2<T extends dynamic, S extends core::String>(lowered final self::Extension3|method2::T% #this) → dynamic {}
+static method Extension3|get#method2<T extends dynamic>(lowered final self::Extension3|get#method2::T% #this) → <S extends core::String>() → dynamic
+  return <S extends core::String>() → dynamic => self::Extension3|method2<self::Extension3|get#method2::T%, S>(#this);
+static method Extension3|method3<T extends dynamic, S extends dynamic>(lowered final self::Extension3|method3::T% #this) → dynamic {}
+static method Extension3|get#method3<T extends dynamic>(lowered final self::Extension3|get#method3::T% #this) → <S extends dynamic>() → dynamic
+  return <S extends dynamic>() → dynamic => self::Extension3|method3<self::Extension3|get#method3::T%, S%>(#this);
+static method Extension3|method4<T extends dynamic, S extends core::Object? = dynamic>(lowered final self::Extension3|method4::T% #this) → dynamic {}
+static method Extension3|get#method4<T extends dynamic>(lowered final self::Extension3|get#method4::T% #this) → <S extends core::Object? = dynamic>() → dynamic
+  return <S extends core::Object? = dynamic>() → dynamic => self::Extension3|method4<self::Extension3|get#method4::T%, S%>(#this);
+static method Extension3|method5<T extends dynamic, S extends core::Object?>(lowered final self::Extension3|method5::T% #this) → dynamic {}
+static method Extension3|get#method5<T extends dynamic>(lowered final self::Extension3|get#method5::T% #this) → <S extends core::Object?>() → dynamic
+  return <S extends core::Object?>() → dynamic => self::Extension3|method5<self::Extension3|get#method5::T%, S%>(#this);
+static method Extension4|method1<T extends core::Object? = dynamic, S extends core::Object>(lowered final self::Extension4|method1::T% #this) → dynamic {}
+static method Extension4|get#method1<T extends core::Object? = dynamic>(lowered final self::Extension4|get#method1::T% #this) → <S extends core::Object>() → dynamic
+  return <S extends core::Object>() → dynamic => self::Extension4|method1<self::Extension4|get#method1::T%, S>(#this);
+static method Extension4|method2<T extends core::Object? = dynamic, S extends core::String>(lowered final self::Extension4|method2::T% #this) → dynamic {}
+static method Extension4|get#method2<T extends core::Object? = dynamic>(lowered final self::Extension4|get#method2::T% #this) → <S extends core::String>() → dynamic
+  return <S extends core::String>() → dynamic => self::Extension4|method2<self::Extension4|get#method2::T%, S>(#this);
+static method Extension4|method3<T extends core::Object? = dynamic, S extends dynamic>(lowered final self::Extension4|method3::T% #this) → dynamic {}
+static method Extension4|get#method3<T extends core::Object? = dynamic>(lowered final self::Extension4|get#method3::T% #this) → <S extends dynamic>() → dynamic
+  return <S extends dynamic>() → dynamic => self::Extension4|method3<self::Extension4|get#method3::T%, S%>(#this);
+static method Extension4|method4<T extends core::Object? = dynamic, S extends core::Object? = dynamic>(lowered final self::Extension4|method4::T% #this) → dynamic {}
+static method Extension4|get#method4<T extends core::Object? = dynamic>(lowered final self::Extension4|get#method4::T% #this) → <S extends core::Object? = dynamic>() → dynamic
+  return <S extends core::Object? = dynamic>() → dynamic => self::Extension4|method4<self::Extension4|get#method4::T%, S%>(#this);
+static method Extension4|method5<T extends core::Object? = dynamic, S extends core::Object?>(lowered final self::Extension4|method5::T% #this) → dynamic {}
+static method Extension4|get#method5<T extends core::Object? = dynamic>(lowered final self::Extension4|get#method5::T% #this) → <S extends core::Object?>() → dynamic
+  return <S extends core::Object?>() → dynamic => self::Extension4|method5<self::Extension4|get#method5::T%, S%>(#this);
+static method Extension5|method1<T extends core::Object?, S extends core::Object>(lowered final self::Extension5|method1::T% #this) → dynamic {}
+static method Extension5|get#method1<T extends core::Object?>(lowered final self::Extension5|get#method1::T% #this) → <S extends core::Object>() → dynamic
+  return <S extends core::Object>() → dynamic => self::Extension5|method1<self::Extension5|get#method1::T%, S>(#this);
+static method Extension5|method2<T extends core::Object?, S extends core::String>(lowered final self::Extension5|method2::T% #this) → dynamic {}
+static method Extension5|get#method2<T extends core::Object?>(lowered final self::Extension5|get#method2::T% #this) → <S extends core::String>() → dynamic
+  return <S extends core::String>() → dynamic => self::Extension5|method2<self::Extension5|get#method2::T%, S>(#this);
+static method Extension5|method3<T extends core::Object?, S extends dynamic>(lowered final self::Extension5|method3::T% #this) → dynamic {}
+static method Extension5|get#method3<T extends core::Object?>(lowered final self::Extension5|get#method3::T% #this) → <S extends dynamic>() → dynamic
+  return <S extends dynamic>() → dynamic => self::Extension5|method3<self::Extension5|get#method3::T%, S%>(#this);
+static method Extension5|method4<T extends core::Object?, S extends core::Object? = dynamic>(lowered final self::Extension5|method4::T% #this) → dynamic {}
+static method Extension5|get#method4<T extends core::Object?>(lowered final self::Extension5|get#method4::T% #this) → <S extends core::Object? = dynamic>() → dynamic
+  return <S extends core::Object? = dynamic>() → dynamic => self::Extension5|method4<self::Extension5|get#method4::T%, S%>(#this);
+static method Extension5|method5<T extends core::Object?, S extends core::Object?>(lowered final self::Extension5|method5::T% #this) → dynamic {}
+static method Extension5|get#method5<T extends core::Object?>(lowered final self::Extension5|get#method5::T% #this) → <S extends core::Object?>() → dynamic
+  return <S extends core::Object?>() → dynamic => self::Extension5|method5<self::Extension5|get#method5::T%, S%>(#this);
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/extension_never.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/extension_never.dart.weak.modular.expect
new file mode 100644
index 0000000..16f18a0
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/extension_never.dart.weak.modular.expect
@@ -0,0 +1,19 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:_internal" as _in;
+
+extension Extension on Never {
+  method extensionMethod = self::Extension|extensionMethod;
+  tearoff extensionMethod = self::Extension|get#extensionMethod;
+}
+static method Extension|extensionMethod(lowered final Never #this) → dynamic {}
+static method Extension|get#extensionMethod(lowered final Never #this) → () → dynamic
+  return () → dynamic => self::Extension|extensionMethod(#this);
+static method implicitAccess(Never never) → dynamic {
+  let final Never #t1 = (let final Never #t2 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.extensionMethod() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never #t3 = (let final Never #t4 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.missingMethod() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+}
+static method explicitAccess(Never never) → dynamic {
+  self::Extension|extensionMethod(let final Never #t5 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."));
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/extension_type_variable_bound.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/extension_type_variable_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..beb5bfc
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/extension_type_variable_bound.dart.weak.modular.expect
@@ -0,0 +1,80 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/extension_type_variable_bound.dart:19:15: Error: A value of type 'T' can't be returned from a function with return type 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/extension_type_variable_bound.dart'.
+//     return t1.method1();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/extension_type_variable_bound.dart:26:28: Error: A value of type 'T' can't be assigned to a variable of type 'SubClass'.
+//  - 'SubClass' is from 'pkg/front_end/testcases/nnbd/extension_type_variable_bound.dart'.
+//     SubClass subClass = t2.method2();
+//                            ^
+//
+// pkg/front_end/testcases/nnbd/extension_type_variable_bound.dart:32:28: Error: The method 'method2' isn't defined for the class 'SubClass'.
+//  - 'SubClass' is from 'pkg/front_end/testcases/nnbd/extension_type_variable_bound.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'method2'.
+//     SubClass subClass = t3.method2();
+//                            ^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+}
+class SubClass extends self::Class {
+  synthetic constructor •() → self::SubClass
+    : super self::Class::•()
+    ;
+}
+extension Extension<T extends core::Object? = dynamic> on T% {
+  method method1 = self::Extension|method1;
+  tearoff method1 = self::Extension|get#method1;
+}
+extension BoundExtension<T extends self::Class> on T {
+  method method2 = self::BoundExtension|method2;
+  tearoff method2 = self::BoundExtension|get#method2;
+}
+static method Extension|method1<T extends core::Object? = dynamic>(lowered final self::Extension|method1::T% #this) → self::Extension|method1::T%
+  return #this;
+static method Extension|get#method1<T extends core::Object? = dynamic>(lowered final self::Extension|get#method1::T% #this) → () → self::Extension|get#method1::T%
+  return () → self::Extension|get#method1::T% => self::Extension|method1<self::Extension|get#method1::T%>(#this);
+static method BoundExtension|method2<T extends self::Class>(lowered final self::BoundExtension|method2::T #this) → self::BoundExtension|method2::T
+  return #this;
+static method BoundExtension|get#method2<T extends self::Class>(lowered final self::BoundExtension|get#method2::T #this) → () → self::BoundExtension|get#method2::T
+  return () → self::BoundExtension|get#method2::T => self::BoundExtension|method2<self::BoundExtension|get#method2::T>(#this);
+static method test1<T extends core::Object? = dynamic>(self::test1::T% t1) → self::Class {
+  if(t1 is{ForNonNullableByDefault} self::SubClass) {
+    return invalid-expression "pkg/front_end/testcases/nnbd/extension_type_variable_bound.dart:19:15: Error: A value of type 'T' can't be returned from a function with return type 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/extension_type_variable_bound.dart'.
+    return t1.method1();
+              ^" in self::Extension|method1<self::test1::T%>(t1{self::test1::T% & self::SubClass /* '%' & '!' = '!' */}) as{TypeError,ForNonNullableByDefault} self::Class;
+  }
+  return new self::Class::•();
+}
+static method test2<T extends self::Class>(self::test2::T t2) → dynamic {
+  if(self::test2::T =={core::Type::==}{(core::Object) → core::bool} #C1) {
+    self::SubClass subClass = invalid-expression "pkg/front_end/testcases/nnbd/extension_type_variable_bound.dart:26:28: Error: A value of type 'T' can't be assigned to a variable of type 'SubClass'.
+ - 'SubClass' is from 'pkg/front_end/testcases/nnbd/extension_type_variable_bound.dart'.
+    SubClass subClass = t2.method2();
+                           ^" in self::BoundExtension|method2<self::test2::T>(t2) as{TypeError,ForNonNullableByDefault} self::SubClass;
+  }
+}
+static method test3<T extends core::Object? = dynamic>(self::test3::T% t3) → dynamic {
+  if(t3 is{ForNonNullableByDefault} self::SubClass) {
+    self::SubClass subClass = invalid-expression "pkg/front_end/testcases/nnbd/extension_type_variable_bound.dart:32:28: Error: The method 'method2' isn't defined for the class 'SubClass'.
+ - 'SubClass' is from 'pkg/front_end/testcases/nnbd/extension_type_variable_bound.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'method2'.
+    SubClass subClass = t3.method2();
+                           ^^^^^^^" in t3{self::test3::T% & self::SubClass /* '%' & '!' = '!' */}{<unresolved>}.method2() as{TypeError,ForDynamic,ForNonNullableByDefault} self::SubClass;
+  }
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = TypeLiteralConstant(self::SubClass*)
+}
diff --git a/pkg/front_end/testcases/nnbd/external_field_errors.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/external_field_errors.dart.weak.modular.expect
new file mode 100644
index 0000000..ec21f8d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/external_field_errors.dart.weak.modular.expect
@@ -0,0 +1,122 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/external_field_errors.dart:5:28: Error: External fields cannot have initializers.
+// Try removing the initializer or the 'external' keyword.
+// external int topLevelField = 0;
+//                            ^
+//
+// pkg/front_end/testcases/nnbd/external_field_errors.dart:7:39: Error: External fields cannot have initializers.
+// Try removing the initializer or the 'external' keyword.
+// external final int finalTopLevelField = 0;
+//                                       ^
+//
+// pkg/front_end/testcases/nnbd/external_field_errors.dart:9:31: Error: External fields cannot have initializers.
+// Try removing the initializer or the 'external' keyword.
+// external const int constField = 0;
+//                               ^
+//
+// pkg/front_end/testcases/nnbd/external_field_errors.dart:12:37: Error: External fields cannot have initializers.
+// Try removing the initializer or the 'external' keyword.
+//   external int fieldWithInitializer = 0;
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/external_field_errors.dart:18:10: Error: External fields cannot have initializers.
+// Try removing the field initializer or the 'external' keyword from the field declaration.
+//   A(this.initializedField1) : this.initializedField2 = 0;
+//          ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/external_field_errors.dart:18:36: Error: External fields cannot have initializers.
+// Try removing the field initializer or the 'external' keyword from the field declaration.
+//   A(this.initializedField1) : this.initializedField2 = 0;
+//                                    ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/external_field_errors.dart:20:35: Error: External fields cannot have initializers.
+// Try removing the initializer or the 'external' keyword.
+//   external static int staticField = 0;
+//                                   ^
+//
+// pkg/front_end/testcases/nnbd/external_field_errors.dart:22:46: Error: External fields cannot have initializers.
+// Try removing the initializer or the 'external' keyword.
+//   external static final int finalStaticField = 0;
+//                                              ^
+//
+// pkg/front_end/testcases/nnbd/external_field_errors.dart:26:35: Error: External fields cannot have initializers.
+// Try removing the initializer or the 'external' keyword.
+//   external static int staticField = 0;
+//                                   ^
+//
+// pkg/front_end/testcases/nnbd/external_field_errors.dart:28:46: Error: External fields cannot have initializers.
+// Try removing the initializer or the 'external' keyword.
+//   external static final int finalStaticField = 0;
+//                                              ^
+//
+// pkg/front_end/testcases/nnbd/external_field_errors.dart:32:39: Error: External fields cannot have initializers.
+// Try removing the initializer or the 'external' keyword.
+//   external int extensionInstanceField = 0;
+//                                       ^
+//
+// pkg/front_end/testcases/nnbd/external_field_errors.dart:33:50: Error: External fields cannot have initializers.
+// Try removing the initializer or the 'external' keyword.
+//   external final int finalExtensionInstanceField = 0;
+//                                                  ^
+//
+// pkg/front_end/testcases/nnbd/external_field_errors.dart:34:44: Error: External fields cannot have initializers.
+// Try removing the initializer or the 'external' keyword.
+//   external static int extensionStaticField = 0;
+//                                            ^
+//
+// pkg/front_end/testcases/nnbd/external_field_errors.dart:35:55: Error: External fields cannot have initializers.
+// Try removing the initializer or the 'external' keyword.
+//   external static final int finalExtensionStaticField = 0;
+//                                                       ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  constructor •(core::int initializedField1) → self::A
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/nnbd/external_field_errors.dart:18:10: Error: External fields cannot have initializers.
+Try removing the field initializer or the 'external' keyword from the field declaration.
+  A(this.initializedField1) : this.initializedField2 = 0;
+         ^^^^^^^^^^^^^^^^^", final dynamic #t2 = invalid-expression "pkg/front_end/testcases/nnbd/external_field_errors.dart:18:36: Error: External fields cannot have initializers.
+Try removing the field initializer or the 'external' keyword from the field declaration.
+  A(this.initializedField1) : this.initializedField2 = 0;
+                                   ^^^^^^^^^^^^^^^^^"
+    ;
+  external get fieldWithInitializer() → core::int;
+  external set fieldWithInitializer(core::int #externalFieldValue) → void;
+  external get initializedField1() → core::int;
+  external set initializedField1(core::int #externalFieldValue) → void;
+  external get initializedField2() → core::int;
+  external set initializedField2(core::int #externalFieldValue) → void;
+  external static get staticField() → core::int;
+  external static set staticField(core::int #externalFieldValue) → void;
+  external static get finalStaticField() → core::int;
+}
+abstract class B extends core::Object /*isMixinDeclaration*/  {
+  external static get staticField() → core::int;
+  external static set staticField(core::int #externalFieldValue) → void;
+  external static get finalStaticField() → core::int;
+}
+extension Extension on self::A {
+  get extensionInstanceField = self::Extension|get#extensionInstanceField;
+  set extensionInstanceField = self::Extension|set#extensionInstanceField;
+  get finalExtensionInstanceField = self::Extension|get#finalExtensionInstanceField;
+  static get extensionStaticField = get self::Extension|extensionStaticField;
+  static set extensionStaticField = set self::Extension|extensionStaticField;
+  static get finalExtensionStaticField = get self::Extension|finalExtensionStaticField;
+}
+external static get topLevelField() → core::int;
+external static set topLevelField(core::int #externalFieldValue) → void;
+external static get finalTopLevelField() → core::int;
+external static get constField() → core::int;
+external static set constField(core::int #externalFieldValue) → void;
+external static method Extension|get#extensionInstanceField(self::A #this) → core::int;
+external static method Extension|set#extensionInstanceField(self::A #this, core::int #externalFieldValue) → void;
+external static method Extension|get#finalExtensionInstanceField(self::A #this) → core::int;
+external static get Extension|extensionStaticField() → core::int;
+external static set Extension|extensionStaticField(core::int #externalFieldValue) → void;
+external static get Extension|finalExtensionStaticField() → core::int;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/external_fields.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/external_fields.dart.weak.modular.expect
new file mode 100644
index 0000000..9ca288c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/external_fields.dart.weak.modular.expect
@@ -0,0 +1,131 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Annotation extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::Annotation
+    : super core::Object::•()
+    ;
+}
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  @#C1
+  external get instanceField() → core::int;
+  @#C1
+  external set instanceField(core::int #externalFieldValue) → void;
+  @#C1
+  external get finalInstanceField() → core::int;
+  @#C1
+  external get covariantInstanceField() → core::num;
+  @#C1
+  external set covariantInstanceField(covariant-by-declaration core::num #externalFieldValue) → void;
+  @#C1
+  external static get staticField() → core::int;
+  @#C1
+  external static set staticField(core::int #externalFieldValue) → void;
+  @#C1
+  external static get finalStaticField() → core::int;
+  external get untypedInstanceField() → dynamic;
+  external set untypedInstanceField(dynamic #externalFieldValue) → void;
+  external get untypedFinalInstanceField() → dynamic;
+  external get untypedCovariantInstanceField() → dynamic;
+  external set untypedCovariantInstanceField(covariant-by-declaration dynamic #externalFieldValue) → void;
+  external static get untypedStaticField() → dynamic;
+  external static set untypedStaticField(dynamic #externalFieldValue) → void;
+  external static get untypedFinalStaticField() → dynamic;
+}
+abstract class B extends core::Object /*isMixinDeclaration*/  {
+  @#C1
+  external get instanceField() → core::int;
+  @#C1
+  external set instanceField(core::int #externalFieldValue) → void;
+  @#C1
+  external get finalInstanceField() → core::int;
+  @#C1
+  external get covariantInstanceField() → core::num;
+  @#C1
+  external set covariantInstanceField(covariant-by-declaration core::num #externalFieldValue) → void;
+  @#C1
+  external static get staticField() → core::int;
+  @#C1
+  external static set staticField(core::int #externalFieldValue) → void;
+  @#C1
+  external static get finalStaticField() → core::int;
+  external get untypedInstanceField() → dynamic;
+  external set untypedInstanceField(dynamic #externalFieldValue) → void;
+  external get untypedFinalInstanceField() → dynamic;
+  external get untypedCovariantInstanceField() → dynamic;
+  external set untypedCovariantInstanceField(covariant-by-declaration dynamic #externalFieldValue) → void;
+  external static get untypedStaticField() → dynamic;
+  external static set untypedStaticField(dynamic #externalFieldValue) → void;
+  external static get untypedFinalStaticField() → dynamic;
+}
+class C extends core::Object implements self::A {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  external get instanceField() → core::int;
+  external set instanceField(core::int #externalFieldValue) → void;
+  external get finalInstanceField() → core::int;
+  external get covariantInstanceField() → core::num;
+  external set covariantInstanceField(covariant-by-declaration core::num #externalFieldValue) → void;
+  external get untypedInstanceField() → dynamic;
+  external set untypedInstanceField(dynamic #externalFieldValue) → void;
+  external get untypedFinalInstanceField() → dynamic;
+  external get untypedCovariantInstanceField() → dynamic;
+  external set untypedCovariantInstanceField(covariant-by-declaration dynamic #externalFieldValue) → void;
+}
+extension Extension on self::A {
+  get extensionInstanceField = self::Extension|get#extensionInstanceField;
+  set extensionInstanceField = self::Extension|set#extensionInstanceField;
+  get finalExtensionInstanceField = self::Extension|get#finalExtensionInstanceField;
+  static get extensionStaticField = get self::Extension|extensionStaticField;
+  static set extensionStaticField = set self::Extension|extensionStaticField;
+  static get finalExtensionStaticField = get self::Extension|finalExtensionStaticField;
+  get untypedExtensionInstanceField = self::Extension|get#untypedExtensionInstanceField;
+  set untypedExtensionInstanceField = self::Extension|set#untypedExtensionInstanceField;
+  get untypedFinalExtensionInstanceField = self::Extension|get#untypedFinalExtensionInstanceField;
+  static get untypedExtensionStaticField = get self::Extension|untypedExtensionStaticField;
+  static set untypedExtensionStaticField = set self::Extension|untypedExtensionStaticField;
+  static get untypedFinalExtensionStaticField = get self::Extension|untypedFinalExtensionStaticField;
+}
+@#C1
+external static get topLevelField() → core::int;
+@#C1
+external static set topLevelField(core::int #externalFieldValue) → void;
+@#C1
+external static get finalTopLevelField() → core::int;
+external static get untypedTopLevelField() → dynamic;
+external static set untypedTopLevelField(dynamic #externalFieldValue) → void;
+external static get untypedFinalTopLevelField() → dynamic;
+@#C1
+external static method Extension|get#extensionInstanceField(self::A #this) → core::int;
+@#C1
+external static method Extension|set#extensionInstanceField(self::A #this, core::int #externalFieldValue) → void;
+@#C1
+external static method Extension|get#finalExtensionInstanceField(self::A #this) → core::int;
+@#C1
+external static get Extension|extensionStaticField() → core::int;
+@#C1
+external static set Extension|extensionStaticField(core::int #externalFieldValue) → void;
+@#C1
+external static get Extension|finalExtensionStaticField() → core::int;
+external static method Extension|get#untypedExtensionInstanceField(self::A #this) → dynamic;
+external static method Extension|set#untypedExtensionInstanceField(self::A #this, dynamic #externalFieldValue) → void;
+external static method Extension|get#untypedFinalExtensionInstanceField(self::A #this) → dynamic;
+external static get Extension|untypedExtensionStaticField() → dynamic;
+external static set Extension|untypedExtensionStaticField(dynamic #externalFieldValue) → void;
+external static get Extension|untypedFinalExtensionStaticField() → dynamic;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = self::Annotation {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///external_fields.dart:
+- Annotation. (from org-dartlang-testcase:///external_fields.dart:6:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/external_fields_spec.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/external_fields_spec.dart.weak.modular.expect
new file mode 100644
index 0000000..d5e1933
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/external_fields_spec.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  external get i1() → core::int;
+  external set i1(core::int #externalFieldValue) → void;
+  external get cx() → dynamic;
+  external set cx(covariant-by-declaration dynamic #externalFieldValue) → void;
+  external static get s1() → core::int;
+  external static set s1(core::int #externalFieldValue) → void;
+  external static get fx() → dynamic;
+}
+external static get s1() → core::int;
+external static set s1(core::int #externalFieldValue) → void;
+external static get fx() → dynamic;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/ffi_sample.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/ffi_sample.dart.weak.modular.expect
new file mode 100644
index 0000000..8fae114
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/ffi_sample.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:ffi" as ffi;
+import "dart:core" as core;
+
+import "dart:ffi";
+import "package:ffi/ffi.dart";
+
+class Coordinate extends ffi::Struct {
+  @#C1
+  external get x() → core::double;
+  @#C1
+  external set x(core::double #externalFieldValue) → void;
+  @#C1
+  external get y() → core::double;
+  @#C1
+  external set y(core::double #externalFieldValue) → void;
+  external get next() → ffi::Pointer<self::Coordinate>;
+  external set next(ffi::Pointer<self::Coordinate> #externalFieldValue) → void;
+  static factory allocate(ffi::Allocator allocator, core::double x, core::double y, ffi::Pointer<self::Coordinate> next) → self::Coordinate {
+    return let final self::Coordinate #t1 = ffi::StructPointer|get#ref<self::Coordinate>(ffi::AllocatorAlloc|call<self::Coordinate>(allocator)) in block {
+      #t1.{self::Coordinate::x} = x;
+      #t1.{self::Coordinate::y} = y;
+      #t1.{self::Coordinate::next} = next;
+    } =>#t1;
+  }
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = ffi::Double {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///ffi_sample.dart:
+- Double. (from org-dartlang-sdk:///sdk/lib/ffi/native_type.dart:122:9)
+- _NativeDouble. (from org-dartlang-sdk:///sdk/lib/ffi/native_type.dart:34:9)
+- NativeType. (from org-dartlang-sdk:///sdk/lib/ffi/native_type.dart:12:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.strong.expect b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.strong.expect
index 0f9dc6d..0db513d 100644
--- a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.strong.expect
+++ b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.strong.expect
@@ -25,5 +25,5 @@
 
 Constructor coverage from constants:
 org-dartlang-testcase:///ffi_struct_inline_array.dart:
-- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:137:9)
+- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:138:9)
 - Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.strong.transformed.expect b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.strong.transformed.expect
index edf8c40..b41e171 100644
--- a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.strong.transformed.expect
@@ -52,5 +52,5 @@
 
 Constructor coverage from constants:
 org-dartlang-testcase:///ffi_struct_inline_array.dart:
-- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:137:9)
+- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:138:9)
 - Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.weak.expect b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.weak.expect
index 732d282..e6c0f95 100644
--- a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.weak.expect
@@ -25,5 +25,5 @@
 
 Constructor coverage from constants:
 org-dartlang-testcase:///ffi_struct_inline_array.dart:
-- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:137:9)
+- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:138:9)
 - Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.weak.modular.expect
new file mode 100644
index 0000000..e6c0f95
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:ffi" as ffi;
+
+import "dart:ffi";
+import "package:ffi/ffi.dart";
+
+class StructInlineArray extends ffi::Struct {
+  synthetic constructor •() → self::StructInlineArray
+    : super ffi::Struct::•()
+    ;
+  @#C3
+  external get a0() → ffi::Array<ffi::Uint8>;
+  @#C3
+  external set a0(ffi::Array<ffi::Uint8> #externalFieldValue) → void;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 8
+  #C2 = null
+  #C3 = ffi::_ArraySize<ffi::NativeType*> {dimension1:#C1, dimension2:#C2, dimension3:#C2, dimension4:#C2, dimension5:#C2, dimensions:#C2}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///ffi_struct_inline_array.dart:
+- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:138:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.weak.transformed.expect
index a445d62..c21a02f 100644
--- a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array.dart.weak.transformed.expect
@@ -52,5 +52,5 @@
 
 Constructor coverage from constants:
 org-dartlang-testcase:///ffi_struct_inline_array.dart:
-- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:137:9)
+- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:138:9)
 - Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.strong.expect b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.strong.expect
index eaeea63..0e058b1 100644
--- a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.strong.expect
+++ b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.strong.expect
@@ -33,5 +33,5 @@
 
 Constructor coverage from constants:
 org-dartlang-testcase:///ffi_struct_inline_array_multi_dimensional.dart:
-- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:137:9)
+- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:138:9)
 - Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.strong.transformed.expect b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.strong.transformed.expect
index c77db0d..dec8714 100644
--- a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.strong.transformed.expect
@@ -84,5 +84,5 @@
 
 Constructor coverage from constants:
 org-dartlang-testcase:///ffi_struct_inline_array_multi_dimensional.dart:
-- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:137:9)
+- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:138:9)
 - Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.weak.expect b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.weak.expect
index b6819cb..5e4b756 100644
--- a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.weak.expect
@@ -33,5 +33,5 @@
 
 Constructor coverage from constants:
 org-dartlang-testcase:///ffi_struct_inline_array_multi_dimensional.dart:
-- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:137:9)
+- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:138:9)
 - Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.weak.modular.expect
new file mode 100644
index 0000000..5e4b756
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:ffi" as ffi;
+
+import "dart:ffi";
+import "package:ffi/ffi.dart";
+
+class StructInlineArrayMultiDimensional extends ffi::Struct {
+  synthetic constructor •() → self::StructInlineArrayMultiDimensional
+    : super ffi::Struct::•()
+    ;
+  @#C3
+  external get a0() → ffi::Array<ffi::Array<ffi::Array<ffi::Uint8>>>;
+  @#C3
+  external set a0(ffi::Array<ffi::Array<ffi::Array<ffi::Uint8>>> #externalFieldValue) → void;
+}
+static method main() → dynamic {
+  final ffi::Pointer<self::StructInlineArrayMultiDimensional> pointer = ffi::AllocatorAlloc|call<self::StructInlineArrayMultiDimensional>(#C4);
+  final self::StructInlineArrayMultiDimensional struct = ffi::StructPointer|get#ref<self::StructInlineArrayMultiDimensional>(pointer);
+  final ffi::Array<ffi::Array<ffi::Array<ffi::Uint8>>> array = struct.{self::StructInlineArrayMultiDimensional::a0}{ffi::Array<ffi::Array<ffi::Array<ffi::Uint8>>>};
+  final ffi::Array<ffi::Array<ffi::Uint8>> subArray = ffi::ArrayArray|[]<ffi::Array<ffi::Uint8>>(array, 0);
+  ffi::ArrayArray|[]=<ffi::Array<ffi::Uint8>>(array, 1, subArray);
+  #C4.{ffi::Allocator::free}(pointer){(ffi::Pointer<ffi::NativeType>) → void};
+}
+
+constants  {
+  #C1 = 2
+  #C2 = null
+  #C3 = ffi::_ArraySize<ffi::NativeType*> {dimension1:#C1, dimension2:#C1, dimension3:#C1, dimension4:#C2, dimension5:#C2, dimensions:#C2}
+  #C4 = all::_CallocAllocator {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///ffi_struct_inline_array_multi_dimensional.dart:
+- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:138:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.weak.transformed.expect
index 7de8504..e5881fb 100644
--- a/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/ffi_struct_inline_array_multi_dimensional.dart.weak.transformed.expect
@@ -84,5 +84,5 @@
 
 Constructor coverage from constants:
 org-dartlang-testcase:///ffi_struct_inline_array_multi_dimensional.dart:
-- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:137:9)
+- _ArraySize. (from org-dartlang-sdk:///sdk/lib/ffi/ffi.dart:138:9)
 - Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/field_setter_conflict.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/field_setter_conflict.dart.weak.modular.expect
new file mode 100644
index 0000000..4dec1df
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/field_setter_conflict.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/field_setter_conflict.dart:7:10: Error: Conflicts with the implicit setter of the field 'topLevelFieldInPartSetterInMain'.
+// void set topLevelFieldInPartSetterInMain(int? value) {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/field_setter_conflict_part.dart:39:6: Error: Conflicts with setter 'topLevelFieldInPartSetterInMain'.
+// int? topLevelFieldInPartSetterInMain;
+//      ^
+//
+// pkg/front_end/testcases/nnbd/field_setter_conflict_part.dart:40:10: Error: Conflicts with the implicit setter of the field 'topLevelFieldInMainSetterInPart'.
+// void set topLevelFieldInMainSetterInPart(int? value) {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/field_setter_conflict.dart:8:6: Error: Conflicts with setter 'topLevelFieldInMainSetterInPart'.
+// int? topLevelFieldInMainSetterInPart;
+//      ^
+//
+import self as self;
+import "dart:core" as core;
+
+part field_setter_conflict_part.dart;
+static field core::int? topLevelFieldInMainSetterInPart;
+static field core::int? topLevelFieldInPartSetterInMain /* from org-dartlang-testcase:///field_setter_conflict_part.dart */;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/field_vs_setter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/field_vs_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..6e42cfb
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/field_vs_setter.dart.weak.modular.expect
@@ -0,0 +1,1348 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:10:10: Error: 'topLevelFieldAndDuplicateSetter' is already declared in this scope.
+// void set topLevelFieldAndDuplicateSetter(int? value) {}
+//          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:9:10: Context: Previous declaration of 'topLevelFieldAndDuplicateSetter'.
+// void set topLevelFieldAndDuplicateSetter(int? value) {}
+//          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:13:12: Error: 'duplicateTopLevelFieldAndSetter1' is already declared in this scope.
+// final int? duplicateTopLevelFieldAndSetter1 = null;
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:12:6: Context: Previous declaration of 'duplicateTopLevelFieldAndSetter1'.
+// int? duplicateTopLevelFieldAndSetter1;
+//      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:17:6: Error: 'duplicateTopLevelFieldAndSetter2' is already declared in this scope.
+// int? duplicateTopLevelFieldAndSetter2;
+//      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:16:12: Context: Previous declaration of 'duplicateTopLevelFieldAndSetter2'.
+// final int? duplicateTopLevelFieldAndSetter2 = null;
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:25:10: Error: 'topLevelLateFinalFieldAndDuplicateSetter' is already declared in this scope.
+// void set topLevelLateFinalFieldAndDuplicateSetter(int? value) {}
+//          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:24:10: Context: Previous declaration of 'topLevelLateFinalFieldAndDuplicateSetter'.
+// void set topLevelLateFinalFieldAndDuplicateSetter(int? value) {}
+//          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:33:12: Error: 'instanceFieldAndDuplicateSetter' is already declared in this scope.
+//   void set instanceFieldAndDuplicateSetter(int? value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:32:12: Context: Previous declaration of 'instanceFieldAndDuplicateSetter'.
+//   void set instanceFieldAndDuplicateSetter(int? value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:36:14: Error: 'duplicateInstanceFieldAndSetter1' is already declared in this scope.
+//   final int? duplicateInstanceFieldAndSetter1 = null;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:35:8: Context: Previous declaration of 'duplicateInstanceFieldAndSetter1'.
+//   int? duplicateInstanceFieldAndSetter1;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:40:8: Error: 'duplicateInstanceFieldAndSetter2' is already declared in this scope.
+//   int? duplicateInstanceFieldAndSetter2;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:39:14: Context: Previous declaration of 'duplicateInstanceFieldAndSetter2'.
+//   final int? duplicateInstanceFieldAndSetter2 = null;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:48:12: Error: 'instanceLateFinalFieldAndDuplicateSetter' is already declared in this scope.
+//   void set instanceLateFinalFieldAndDuplicateSetter(int? value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:47:12: Context: Previous declaration of 'instanceLateFinalFieldAndDuplicateSetter'.
+//   void set instanceLateFinalFieldAndDuplicateSetter(int? value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:55:19: Error: 'staticFieldAndDuplicateSetter' is already declared in this scope.
+//   static void set staticFieldAndDuplicateSetter(int? value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:54:19: Context: Previous declaration of 'staticFieldAndDuplicateSetter'.
+//   static void set staticFieldAndDuplicateSetter(int? value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:58:21: Error: 'duplicateStaticFieldAndSetter1' is already declared in this scope.
+//   static final int? duplicateStaticFieldAndSetter1 = null;
+//                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:57:15: Context: Previous declaration of 'duplicateStaticFieldAndSetter1'.
+//   static int? duplicateStaticFieldAndSetter1;
+//               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:62:15: Error: 'duplicateStaticFieldAndSetter2' is already declared in this scope.
+//   static int? duplicateStaticFieldAndSetter2;
+//               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:61:21: Context: Previous declaration of 'duplicateStaticFieldAndSetter2'.
+//   static final int? duplicateStaticFieldAndSetter2 = null;
+//                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:70:19: Error: 'staticLateFinalFieldAndDuplicateSetter' is already declared in this scope.
+//   static void set staticLateFinalFieldAndDuplicateSetter(int? value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:69:19: Context: Previous declaration of 'staticLateFinalFieldAndDuplicateSetter'.
+//   static void set staticLateFinalFieldAndDuplicateSetter(int? value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:77:12: Error: 'staticFieldAndInstanceDuplicateSetter' is already declared in this scope.
+//   void set staticFieldAndInstanceDuplicateSetter(int? value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:76:12: Context: Previous declaration of 'staticFieldAndInstanceDuplicateSetter'.
+//   void set staticFieldAndInstanceDuplicateSetter(int? value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:84:19: Error: 'instanceFieldAndStaticDuplicateSetter' is already declared in this scope.
+//   static void set instanceFieldAndStaticDuplicateSetter(int? value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:83:19: Context: Previous declaration of 'instanceFieldAndStaticDuplicateSetter'.
+//   static void set instanceFieldAndStaticDuplicateSetter(int? value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:87:14: Error: 'duplicateInstanceFieldAndStaticSetter1' is already declared in this scope.
+//   final int? duplicateInstanceFieldAndStaticSetter1 = null;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:86:8: Context: Previous declaration of 'duplicateInstanceFieldAndStaticSetter1'.
+//   int? duplicateInstanceFieldAndStaticSetter1;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:91:8: Error: 'duplicateInstanceFieldAndStaticSetter2' is already declared in this scope.
+//   int? duplicateInstanceFieldAndStaticSetter2;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:90:14: Context: Previous declaration of 'duplicateInstanceFieldAndStaticSetter2'.
+//   final int? duplicateInstanceFieldAndStaticSetter2 = null;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:95:21: Error: 'duplicateStaticFieldAndInstanceSetter1' is already declared in this scope.
+//   static final int? duplicateStaticFieldAndInstanceSetter1 = null;
+//                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:94:15: Context: Previous declaration of 'duplicateStaticFieldAndInstanceSetter1'.
+//   static int? duplicateStaticFieldAndInstanceSetter1;
+//               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:99:15: Error: 'duplicateStaticFieldAndInstanceSetter2' is already declared in this scope.
+//   static int? duplicateStaticFieldAndInstanceSetter2;
+//               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:98:21: Context: Previous declaration of 'duplicateStaticFieldAndInstanceSetter2'.
+//   static final int? duplicateStaticFieldAndInstanceSetter2 = null;
+//                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:104:8: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int? extensionInstanceFieldAndSetter;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:107:8: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int? extensionInstanceFieldAndDuplicateSetter;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:109:12: Error: 'extensionInstanceFieldAndDuplicateSetter' is already declared in this scope.
+//   void set extensionInstanceFieldAndDuplicateSetter(int? value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:108:12: Context: Previous declaration of 'extensionInstanceFieldAndDuplicateSetter'.
+//   void set extensionInstanceFieldAndDuplicateSetter(int? value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:111:8: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int? duplicateExtensionInstanceFieldAndSetter1;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:112:14: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   final int? duplicateExtensionInstanceFieldAndSetter1 = null;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:112:14: Error: 'duplicateExtensionInstanceFieldAndSetter1' is already declared in this scope.
+//   final int? duplicateExtensionInstanceFieldAndSetter1 = null;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:111:8: Context: Previous declaration of 'duplicateExtensionInstanceFieldAndSetter1'.
+//   int? duplicateExtensionInstanceFieldAndSetter1;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:115:14: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   final int? duplicateExtensionInstanceFieldAndSetter2 = null;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:116:8: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int? duplicateExtensionInstanceFieldAndSetter2;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:116:8: Error: 'duplicateExtensionInstanceFieldAndSetter2' is already declared in this scope.
+//   int? duplicateExtensionInstanceFieldAndSetter2;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:115:14: Context: Previous declaration of 'duplicateExtensionInstanceFieldAndSetter2'.
+//   final int? duplicateExtensionInstanceFieldAndSetter2 = null;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:124:19: Error: 'extensionStaticFieldAndDuplicateSetter' is already declared in this scope.
+//   static void set extensionStaticFieldAndDuplicateSetter(int? value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:123:19: Context: Previous declaration of 'extensionStaticFieldAndDuplicateSetter'.
+//   static void set extensionStaticFieldAndDuplicateSetter(int? value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:127:21: Error: 'duplicateExtensionStaticFieldAndSetter1' is already declared in this scope.
+//   static final int? duplicateExtensionStaticFieldAndSetter1 = null;
+//                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:126:15: Context: Previous declaration of 'duplicateExtensionStaticFieldAndSetter1'.
+//   static int? duplicateExtensionStaticFieldAndSetter1;
+//               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:131:15: Error: 'duplicateExtensionStaticFieldAndSetter2' is already declared in this scope.
+//   static int? duplicateExtensionStaticFieldAndSetter2;
+//               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:130:21: Context: Previous declaration of 'duplicateExtensionStaticFieldAndSetter2'.
+//   static final int? duplicateExtensionStaticFieldAndSetter2 = null;
+//                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:139:19: Error: 'extensionStaticLateFinalFieldAndDuplicateSetter' is already declared in this scope.
+//   static void set extensionStaticLateFinalFieldAndDuplicateSetter(int? value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:138:19: Context: Previous declaration of 'extensionStaticLateFinalFieldAndDuplicateSetter'.
+//   static void set extensionStaticLateFinalFieldAndDuplicateSetter(int? value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:146:12: Error: 'extensionStaticFieldAndInstanceDuplicateSetter' is already declared in this scope.
+//   void set extensionStaticFieldAndInstanceDuplicateSetter(int? value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:145:12: Context: Previous declaration of 'extensionStaticFieldAndInstanceDuplicateSetter'.
+//   void set extensionStaticFieldAndInstanceDuplicateSetter(int? value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:148:8: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int? extensionInstanceFieldAndStaticSetter;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:151:8: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int? extensionInstanceFieldAndStaticDuplicateSetter;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:153:19: Error: 'extensionInstanceFieldAndStaticDuplicateSetter' is already declared in this scope.
+//   static void set extensionInstanceFieldAndStaticDuplicateSetter(int? value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:152:19: Context: Previous declaration of 'extensionInstanceFieldAndStaticDuplicateSetter'.
+//   static void set extensionInstanceFieldAndStaticDuplicateSetter(int? value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:155:8: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int? duplicateExtensionInstanceFieldAndStaticSetter1;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:156:14: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   final int? duplicateExtensionInstanceFieldAndStaticSetter1 = null;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:156:14: Error: 'duplicateExtensionInstanceFieldAndStaticSetter1' is already declared in this scope.
+//   final int? duplicateExtensionInstanceFieldAndStaticSetter1 = null;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:155:8: Context: Previous declaration of 'duplicateExtensionInstanceFieldAndStaticSetter1'.
+//   int? duplicateExtensionInstanceFieldAndStaticSetter1;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:159:14: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   final int? duplicateExtensionInstanceFieldAndStaticSetter2 = null;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:160:8: Error: Extensions can't declare instance fields
+// Try removing the field declaration or making it a static field
+//   int? duplicateExtensionInstanceFieldAndStaticSetter2;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:160:8: Error: 'duplicateExtensionInstanceFieldAndStaticSetter2' is already declared in this scope.
+//   int? duplicateExtensionInstanceFieldAndStaticSetter2;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:159:14: Context: Previous declaration of 'duplicateExtensionInstanceFieldAndStaticSetter2'.
+//   final int? duplicateExtensionInstanceFieldAndStaticSetter2 = null;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:164:21: Error: 'duplicateExtensionStaticFieldAndInstanceSetter1' is already declared in this scope.
+//   static final int? duplicateExtensionStaticFieldAndInstanceSetter1 = null;
+//                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:163:15: Context: Previous declaration of 'duplicateExtensionStaticFieldAndInstanceSetter1'.
+//   static int? duplicateExtensionStaticFieldAndInstanceSetter1;
+//               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:168:15: Error: 'duplicateExtensionStaticFieldAndInstanceSetter2' is already declared in this scope.
+//   static int? duplicateExtensionStaticFieldAndInstanceSetter2;
+//               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:167:21: Context: Previous declaration of 'duplicateExtensionStaticFieldAndInstanceSetter2'.
+//   static final int? duplicateExtensionStaticFieldAndInstanceSetter2 = null;
+//                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart: Error: 'topLevelFieldAndDuplicateSetter' is exported from both 'pkg/front_end/testcases/nnbd/field_vs_setter.dart' and 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart: Error: 'topLevelLateFinalFieldAndDuplicateSetter' is exported from both 'pkg/front_end/testcases/nnbd/field_vs_setter.dart' and 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:6:10: Error: Conflicts with the implicit setter of the field 'topLevelFieldAndSetter'.
+// void set topLevelFieldAndSetter(int? value) {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:5:6: Error: Conflicts with setter 'topLevelFieldAndSetter'.
+// int? topLevelFieldAndSetter;
+//      ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:10:10: Error: Conflicts with the implicit setter of the field 'topLevelFieldAndDuplicateSetter'.
+// void set topLevelFieldAndDuplicateSetter(int? value) {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:9:10: Error: Conflicts with the implicit setter of the field 'topLevelFieldAndDuplicateSetter'.
+// void set topLevelFieldAndDuplicateSetter(int? value) {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:8:6: Error: Conflicts with setter 'topLevelFieldAndDuplicateSetter'.
+// int? topLevelFieldAndDuplicateSetter;
+//      ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:14:10: Error: Conflicts with the implicit setter of the field 'duplicateTopLevelFieldAndSetter1'.
+// void set duplicateTopLevelFieldAndSetter1(int? value) {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:12:6: Error: Conflicts with setter 'duplicateTopLevelFieldAndSetter1'.
+// int? duplicateTopLevelFieldAndSetter1;
+//      ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:18:10: Error: Conflicts with the implicit setter of the field 'duplicateTopLevelFieldAndSetter2'.
+// void set duplicateTopLevelFieldAndSetter2(int? value) {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:17:6: Error: Conflicts with setter 'duplicateTopLevelFieldAndSetter2'.
+// int? duplicateTopLevelFieldAndSetter2;
+//      ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:21:10: Error: Conflicts with the implicit setter of the field 'topLevelLateFinalFieldAndSetter'.
+// void set topLevelLateFinalFieldAndSetter(int? value) {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:20:17: Error: Conflicts with setter 'topLevelLateFinalFieldAndSetter'.
+// late final int? topLevelLateFinalFieldAndSetter;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:25:10: Error: Conflicts with the implicit setter of the field 'topLevelLateFinalFieldAndDuplicateSetter'.
+// void set topLevelLateFinalFieldAndDuplicateSetter(int? value) {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:24:10: Error: Conflicts with the implicit setter of the field 'topLevelLateFinalFieldAndDuplicateSetter'.
+// void set topLevelLateFinalFieldAndDuplicateSetter(int? value) {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:23:17: Error: Conflicts with setter 'topLevelLateFinalFieldAndDuplicateSetter'.
+// late final int? topLevelLateFinalFieldAndDuplicateSetter;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:29:12: Error: Conflicts with the implicit setter of the field 'instanceFieldAndSetter'.
+//   void set instanceFieldAndSetter(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:28:8: Error: Conflicts with setter 'instanceFieldAndSetter'.
+//   int? instanceFieldAndSetter;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:33:12: Error: Conflicts with the implicit setter of the field 'instanceFieldAndDuplicateSetter'.
+//   void set instanceFieldAndDuplicateSetter(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:32:12: Error: Conflicts with the implicit setter of the field 'instanceFieldAndDuplicateSetter'.
+//   void set instanceFieldAndDuplicateSetter(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:31:8: Error: Conflicts with setter 'instanceFieldAndDuplicateSetter'.
+//   int? instanceFieldAndDuplicateSetter;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:37:12: Error: Conflicts with the implicit setter of the field 'duplicateInstanceFieldAndSetter1'.
+//   void set duplicateInstanceFieldAndSetter1(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:35:8: Error: Conflicts with setter 'duplicateInstanceFieldAndSetter1'.
+//   int? duplicateInstanceFieldAndSetter1;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:41:12: Error: Conflicts with the implicit setter of the field 'duplicateInstanceFieldAndSetter2'.
+//   void set duplicateInstanceFieldAndSetter2(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:40:8: Error: Conflicts with setter 'duplicateInstanceFieldAndSetter2'.
+//   int? duplicateInstanceFieldAndSetter2;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:44:12: Error: Conflicts with the implicit setter of the field 'instanceLateFinalFieldAndSetter'.
+//   void set instanceLateFinalFieldAndSetter(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:43:19: Error: Conflicts with setter 'instanceLateFinalFieldAndSetter'.
+//   late final int? instanceLateFinalFieldAndSetter;
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:48:12: Error: Conflicts with the implicit setter of the field 'instanceLateFinalFieldAndDuplicateSetter'.
+//   void set instanceLateFinalFieldAndDuplicateSetter(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:47:12: Error: Conflicts with the implicit setter of the field 'instanceLateFinalFieldAndDuplicateSetter'.
+//   void set instanceLateFinalFieldAndDuplicateSetter(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:46:19: Error: Conflicts with setter 'instanceLateFinalFieldAndDuplicateSetter'.
+//   late final int? instanceLateFinalFieldAndDuplicateSetter;
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:51:19: Error: Conflicts with the implicit setter of the field 'staticFieldAndSetter'.
+//   static void set staticFieldAndSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:50:15: Error: Conflicts with setter 'staticFieldAndSetter'.
+//   static int? staticFieldAndSetter;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:55:19: Error: Conflicts with the implicit setter of the field 'staticFieldAndDuplicateSetter'.
+//   static void set staticFieldAndDuplicateSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:54:19: Error: Conflicts with the implicit setter of the field 'staticFieldAndDuplicateSetter'.
+//   static void set staticFieldAndDuplicateSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:53:15: Error: Conflicts with setter 'staticFieldAndDuplicateSetter'.
+//   static int? staticFieldAndDuplicateSetter;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:59:19: Error: Conflicts with the implicit setter of the field 'duplicateStaticFieldAndSetter1'.
+//   static void set duplicateStaticFieldAndSetter1(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:57:15: Error: Conflicts with setter 'duplicateStaticFieldAndSetter1'.
+//   static int? duplicateStaticFieldAndSetter1;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:63:19: Error: Conflicts with the implicit setter of the field 'duplicateStaticFieldAndSetter2'.
+//   static void set duplicateStaticFieldAndSetter2(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:62:15: Error: Conflicts with setter 'duplicateStaticFieldAndSetter2'.
+//   static int? duplicateStaticFieldAndSetter2;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:66:19: Error: Conflicts with the implicit setter of the field 'staticLateFinalFieldAndSetter'.
+//   static void set staticLateFinalFieldAndSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:65:26: Error: Conflicts with setter 'staticLateFinalFieldAndSetter'.
+//   static late final int? staticLateFinalFieldAndSetter;
+//                          ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:70:19: Error: Conflicts with the implicit setter of the field 'staticLateFinalFieldAndDuplicateSetter'.
+//   static void set staticLateFinalFieldAndDuplicateSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:69:19: Error: Conflicts with the implicit setter of the field 'staticLateFinalFieldAndDuplicateSetter'.
+//   static void set staticLateFinalFieldAndDuplicateSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:68:26: Error: Conflicts with setter 'staticLateFinalFieldAndDuplicateSetter'.
+//   static late final int? staticLateFinalFieldAndDuplicateSetter;
+//                          ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:73:12: Error: Conflicts with the implicit setter of the field 'staticFieldAndInstanceSetter'.
+//   void set staticFieldAndInstanceSetter(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:72:15: Error: Conflicts with setter 'staticFieldAndInstanceSetter'.
+//   static int? staticFieldAndInstanceSetter;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:77:12: Error: Conflicts with the implicit setter of the field 'staticFieldAndInstanceDuplicateSetter'.
+//   void set staticFieldAndInstanceDuplicateSetter(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:76:12: Error: Conflicts with the implicit setter of the field 'staticFieldAndInstanceDuplicateSetter'.
+//   void set staticFieldAndInstanceDuplicateSetter(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:75:15: Error: Conflicts with setter 'staticFieldAndInstanceDuplicateSetter'.
+//   static int? staticFieldAndInstanceDuplicateSetter;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:80:19: Error: Conflicts with the implicit setter of the field 'instanceFieldAndStaticSetter'.
+//   static void set instanceFieldAndStaticSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:79:8: Error: Conflicts with setter 'instanceFieldAndStaticSetter'.
+//   int? instanceFieldAndStaticSetter;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:84:19: Error: Conflicts with the implicit setter of the field 'instanceFieldAndStaticDuplicateSetter'.
+//   static void set instanceFieldAndStaticDuplicateSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:83:19: Error: Conflicts with the implicit setter of the field 'instanceFieldAndStaticDuplicateSetter'.
+//   static void set instanceFieldAndStaticDuplicateSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:82:8: Error: Conflicts with setter 'instanceFieldAndStaticDuplicateSetter'.
+//   int? instanceFieldAndStaticDuplicateSetter;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:88:19: Error: Conflicts with the implicit setter of the field 'duplicateInstanceFieldAndStaticSetter1'.
+//   static void set duplicateInstanceFieldAndStaticSetter1(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:86:8: Error: Conflicts with setter 'duplicateInstanceFieldAndStaticSetter1'.
+//   int? duplicateInstanceFieldAndStaticSetter1;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:92:19: Error: Conflicts with the implicit setter of the field 'duplicateInstanceFieldAndStaticSetter2'.
+//   static void set duplicateInstanceFieldAndStaticSetter2(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:91:8: Error: Conflicts with setter 'duplicateInstanceFieldAndStaticSetter2'.
+//   int? duplicateInstanceFieldAndStaticSetter2;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:96:12: Error: Conflicts with the implicit setter of the field 'duplicateStaticFieldAndInstanceSetter1'.
+//   void set duplicateStaticFieldAndInstanceSetter1(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:94:15: Error: Conflicts with setter 'duplicateStaticFieldAndInstanceSetter1'.
+//   static int? duplicateStaticFieldAndInstanceSetter1;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:100:12: Error: Conflicts with the implicit setter of the field 'duplicateStaticFieldAndInstanceSetter2'.
+//   void set duplicateStaticFieldAndInstanceSetter2(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:99:15: Error: Conflicts with setter 'duplicateStaticFieldAndInstanceSetter2'.
+//   static int? duplicateStaticFieldAndInstanceSetter2;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:105:12: Error: Conflicts with the implicit setter of the field 'extensionInstanceFieldAndSetter'.
+//   void set extensionInstanceFieldAndSetter(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:104:8: Error: Conflicts with setter 'extensionInstanceFieldAndSetter'.
+//   int? extensionInstanceFieldAndSetter;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:109:12: Error: Conflicts with the implicit setter of the field 'extensionInstanceFieldAndDuplicateSetter'.
+//   void set extensionInstanceFieldAndDuplicateSetter(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:108:12: Error: Conflicts with the implicit setter of the field 'extensionInstanceFieldAndDuplicateSetter'.
+//   void set extensionInstanceFieldAndDuplicateSetter(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:107:8: Error: Conflicts with setter 'extensionInstanceFieldAndDuplicateSetter'.
+//   int? extensionInstanceFieldAndDuplicateSetter;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:113:12: Error: Conflicts with the implicit setter of the field 'duplicateExtensionInstanceFieldAndSetter1'.
+//   void set duplicateExtensionInstanceFieldAndSetter1(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:111:8: Error: Conflicts with setter 'duplicateExtensionInstanceFieldAndSetter1'.
+//   int? duplicateExtensionInstanceFieldAndSetter1;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:117:12: Error: Conflicts with the implicit setter of the field 'duplicateExtensionInstanceFieldAndSetter2'.
+//   void set duplicateExtensionInstanceFieldAndSetter2(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:116:8: Error: Conflicts with setter 'duplicateExtensionInstanceFieldAndSetter2'.
+//   int? duplicateExtensionInstanceFieldAndSetter2;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:120:19: Error: Conflicts with the implicit setter of the field 'extensionStaticFieldAndSetter'.
+//   static void set extensionStaticFieldAndSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:119:15: Error: Conflicts with setter 'extensionStaticFieldAndSetter'.
+//   static int? extensionStaticFieldAndSetter;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:124:19: Error: Conflicts with the implicit setter of the field 'extensionStaticFieldAndDuplicateSetter'.
+//   static void set extensionStaticFieldAndDuplicateSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:123:19: Error: Conflicts with the implicit setter of the field 'extensionStaticFieldAndDuplicateSetter'.
+//   static void set extensionStaticFieldAndDuplicateSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:122:15: Error: Conflicts with setter 'extensionStaticFieldAndDuplicateSetter'.
+//   static int? extensionStaticFieldAndDuplicateSetter;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:128:19: Error: Conflicts with the implicit setter of the field 'duplicateExtensionStaticFieldAndSetter1'.
+//   static void set duplicateExtensionStaticFieldAndSetter1(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:126:15: Error: Conflicts with setter 'duplicateExtensionStaticFieldAndSetter1'.
+//   static int? duplicateExtensionStaticFieldAndSetter1;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:132:19: Error: Conflicts with the implicit setter of the field 'duplicateExtensionStaticFieldAndSetter2'.
+//   static void set duplicateExtensionStaticFieldAndSetter2(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:131:15: Error: Conflicts with setter 'duplicateExtensionStaticFieldAndSetter2'.
+//   static int? duplicateExtensionStaticFieldAndSetter2;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:135:19: Error: Conflicts with the implicit setter of the field 'extensionStaticLateFinalFieldAndSetter'.
+//   static void set extensionStaticLateFinalFieldAndSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:134:26: Error: Conflicts with setter 'extensionStaticLateFinalFieldAndSetter'.
+//   static late final int? extensionStaticLateFinalFieldAndSetter;
+//                          ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:139:19: Error: Conflicts with the implicit setter of the field 'extensionStaticLateFinalFieldAndDuplicateSetter'.
+//   static void set extensionStaticLateFinalFieldAndDuplicateSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:138:19: Error: Conflicts with the implicit setter of the field 'extensionStaticLateFinalFieldAndDuplicateSetter'.
+//   static void set extensionStaticLateFinalFieldAndDuplicateSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:137:26: Error: Conflicts with setter 'extensionStaticLateFinalFieldAndDuplicateSetter'.
+//   static late final int? extensionStaticLateFinalFieldAndDuplicateSetter;
+//                          ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:142:12: Error: Conflicts with the implicit setter of the field 'extensionStaticFieldAndInstanceSetter'.
+//   void set extensionStaticFieldAndInstanceSetter(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:141:15: Error: Conflicts with setter 'extensionStaticFieldAndInstanceSetter'.
+//   static int? extensionStaticFieldAndInstanceSetter;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:146:12: Error: Conflicts with the implicit setter of the field 'extensionStaticFieldAndInstanceDuplicateSetter'.
+//   void set extensionStaticFieldAndInstanceDuplicateSetter(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:145:12: Error: Conflicts with the implicit setter of the field 'extensionStaticFieldAndInstanceDuplicateSetter'.
+//   void set extensionStaticFieldAndInstanceDuplicateSetter(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:144:15: Error: Conflicts with setter 'extensionStaticFieldAndInstanceDuplicateSetter'.
+//   static int? extensionStaticFieldAndInstanceDuplicateSetter;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:149:19: Error: Conflicts with the implicit setter of the field 'extensionInstanceFieldAndStaticSetter'.
+//   static void set extensionInstanceFieldAndStaticSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:148:8: Error: Conflicts with setter 'extensionInstanceFieldAndStaticSetter'.
+//   int? extensionInstanceFieldAndStaticSetter;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:153:19: Error: Conflicts with the implicit setter of the field 'extensionInstanceFieldAndStaticDuplicateSetter'.
+//   static void set extensionInstanceFieldAndStaticDuplicateSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:152:19: Error: Conflicts with the implicit setter of the field 'extensionInstanceFieldAndStaticDuplicateSetter'.
+//   static void set extensionInstanceFieldAndStaticDuplicateSetter(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:151:8: Error: Conflicts with setter 'extensionInstanceFieldAndStaticDuplicateSetter'.
+//   int? extensionInstanceFieldAndStaticDuplicateSetter;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:157:19: Error: Conflicts with the implicit setter of the field 'duplicateExtensionInstanceFieldAndStaticSetter1'.
+//   static void set duplicateExtensionInstanceFieldAndStaticSetter1(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:155:8: Error: Conflicts with setter 'duplicateExtensionInstanceFieldAndStaticSetter1'.
+//   int? duplicateExtensionInstanceFieldAndStaticSetter1;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:156:14: Error: Conflicts with setter 'duplicateExtensionInstanceFieldAndStaticSetter1'.
+//   final int? duplicateExtensionInstanceFieldAndStaticSetter1 = null;
+//              ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:161:19: Error: Conflicts with the implicit setter of the field 'duplicateExtensionInstanceFieldAndStaticSetter2'.
+//   static void set duplicateExtensionInstanceFieldAndStaticSetter2(int? value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:160:8: Error: Conflicts with setter 'duplicateExtensionInstanceFieldAndStaticSetter2'.
+//   int? duplicateExtensionInstanceFieldAndStaticSetter2;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:159:14: Error: Conflicts with setter 'duplicateExtensionInstanceFieldAndStaticSetter2'.
+//   final int? duplicateExtensionInstanceFieldAndStaticSetter2 = null;
+//              ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:165:12: Error: Conflicts with the implicit setter of the field 'duplicateExtensionStaticFieldAndInstanceSetter1'.
+//   void set duplicateExtensionStaticFieldAndInstanceSetter1(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:163:15: Error: Conflicts with setter 'duplicateExtensionStaticFieldAndInstanceSetter1'.
+//   static int? duplicateExtensionStaticFieldAndInstanceSetter1;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:164:21: Error: Conflicts with setter 'duplicateExtensionStaticFieldAndInstanceSetter1'.
+//   static final int? duplicateExtensionStaticFieldAndInstanceSetter1 = null;
+//                     ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:169:12: Error: Conflicts with the implicit setter of the field 'duplicateExtensionStaticFieldAndInstanceSetter2'.
+//   void set duplicateExtensionStaticFieldAndInstanceSetter2(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:168:15: Error: Conflicts with setter 'duplicateExtensionStaticFieldAndInstanceSetter2'.
+//   static int? duplicateExtensionStaticFieldAndInstanceSetter2;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:167:21: Error: Conflicts with setter 'duplicateExtensionStaticFieldAndInstanceSetter2'.
+//   static final int? duplicateExtensionStaticFieldAndInstanceSetter2 = null;
+//                     ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:178:38: Error: Can't use 'duplicateTopLevelFieldAndSetter1' because it is declared more than once.
+//   duplicateTopLevelFieldAndSetter1 = duplicateTopLevelFieldAndSetter1;
+//                                      ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:178:36: Error: Can't assign to this.
+//   duplicateTopLevelFieldAndSetter1 = duplicateTopLevelFieldAndSetter1;
+//                                    ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:179:38: Error: Can't use 'duplicateTopLevelFieldAndSetter2' because it is declared more than once.
+//   duplicateTopLevelFieldAndSetter2 = duplicateTopLevelFieldAndSetter2;
+//                                      ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:179:36: Error: Can't assign to this.
+//   duplicateTopLevelFieldAndSetter2 = duplicateTopLevelFieldAndSetter2;
+//                                    ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:198:9: Error: Can't use 'duplicateStaticFieldAndSetter1' because it is declared more than once.
+//   Class.duplicateStaticFieldAndSetter1 = Class.duplicateStaticFieldAndSetter1;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:198:48: Error: Can't use 'duplicateStaticFieldAndSetter1' because it is declared more than once.
+//   Class.duplicateStaticFieldAndSetter1 = Class.duplicateStaticFieldAndSetter1;
+//                                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:198:40: Error: Can't assign to this.
+//   Class.duplicateStaticFieldAndSetter1 = Class.duplicateStaticFieldAndSetter1;
+//                                        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:199:9: Error: Can't use 'duplicateStaticFieldAndSetter2' because it is declared more than once.
+//   Class.duplicateStaticFieldAndSetter2 = Class.duplicateStaticFieldAndSetter2;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:199:48: Error: Can't use 'duplicateStaticFieldAndSetter2' because it is declared more than once.
+//   Class.duplicateStaticFieldAndSetter2 = Class.duplicateStaticFieldAndSetter2;
+//                                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:199:40: Error: Can't assign to this.
+//   Class.duplicateStaticFieldAndSetter2 = Class.duplicateStaticFieldAndSetter2;
+//                                        ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:209:9: Error: Setter not found: 'instanceFieldAndStaticSetter'.
+//   Class.instanceFieldAndStaticSetter = c.instanceFieldAndStaticSetter;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:212:9: Error: Can't use 'instanceFieldAndStaticDuplicateSetter' because it is declared more than once.
+//   Class.instanceFieldAndStaticDuplicateSetter =
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:212:47: Error: Can't assign to this.
+//   Class.instanceFieldAndStaticDuplicateSetter =
+//                                               ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:218:13: Error: Can't use 'duplicateStaticFieldAndInstanceSetter1' because it is declared more than once.
+//       Class.duplicateStaticFieldAndInstanceSetter1;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:219:9: Error: Can't use 'duplicateStaticFieldAndInstanceSetter1' because it is declared more than once.
+//   Class.duplicateStaticFieldAndInstanceSetter1 =
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:220:13: Error: Can't use 'duplicateStaticFieldAndInstanceSetter1' because it is declared more than once.
+//       Class.duplicateStaticFieldAndInstanceSetter1;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:219:48: Error: Can't assign to this.
+//   Class.duplicateStaticFieldAndInstanceSetter1 =
+//                                                ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:223:13: Error: Can't use 'duplicateStaticFieldAndInstanceSetter2' because it is declared more than once.
+//       Class.duplicateStaticFieldAndInstanceSetter2;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:224:9: Error: Can't use 'duplicateStaticFieldAndInstanceSetter2' because it is declared more than once.
+//   Class.duplicateStaticFieldAndInstanceSetter2 =
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:225:13: Error: Can't use 'duplicateStaticFieldAndInstanceSetter2' because it is declared more than once.
+//       Class.duplicateStaticFieldAndInstanceSetter2;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:224:48: Error: Can't assign to this.
+//   Class.duplicateStaticFieldAndInstanceSetter2 =
+//                                                ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:227:9: Error: Can't use 'duplicateInstanceFieldAndStaticSetter1' because it is declared more than once.
+//   Class.duplicateInstanceFieldAndStaticSetter1 =
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:227:48: Error: Can't assign to this.
+//   Class.duplicateInstanceFieldAndStaticSetter1 =
+//                                                ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:229:9: Error: Can't use 'duplicateInstanceFieldAndStaticSetter2' because it is declared more than once.
+//   Class.duplicateInstanceFieldAndStaticSetter2 =
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:229:48: Error: Can't assign to this.
+//   Class.duplicateInstanceFieldAndStaticSetter2 =
+//                                                ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:252:13: Error: Can't use 'duplicateExtensionStaticFieldAndSetter1' because it is declared more than once.
+//   Extension.duplicateExtensionStaticFieldAndSetter1 =
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:253:17: Error: Can't use 'duplicateExtensionStaticFieldAndSetter1' because it is declared more than once.
+//       Extension.duplicateExtensionStaticFieldAndSetter1;
+//                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:252:53: Error: Can't assign to this.
+//   Extension.duplicateExtensionStaticFieldAndSetter1 =
+//                                                     ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:254:13: Error: Can't use 'duplicateExtensionStaticFieldAndSetter2' because it is declared more than once.
+//   Extension.duplicateExtensionStaticFieldAndSetter2 =
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:255:17: Error: Can't use 'duplicateExtensionStaticFieldAndSetter2' because it is declared more than once.
+//       Extension.duplicateExtensionStaticFieldAndSetter2;
+//                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:254:53: Error: Can't assign to this.
+//   Extension.duplicateExtensionStaticFieldAndSetter2 =
+//                                                     ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:267:13: Error: Setter not found: 'extensionInstanceFieldAndStaticSetter'.
+//   Extension.extensionInstanceFieldAndStaticSetter =
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:272:13: Error: Can't use 'extensionInstanceFieldAndStaticDuplicateSetter' because it is declared more than once.
+//   Extension.extensionInstanceFieldAndStaticDuplicateSetter =
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:272:60: Error: Can't assign to this.
+//   Extension.extensionInstanceFieldAndStaticDuplicateSetter =
+//                                                            ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:277:13: Error: Can't use 'duplicateExtensionInstanceFieldAndStaticSetter1' because it is declared more than once.
+//   Extension.duplicateExtensionInstanceFieldAndStaticSetter1 =
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:277:61: Error: Can't assign to this.
+//   Extension.duplicateExtensionInstanceFieldAndStaticSetter1 =
+//                                                             ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:282:13: Error: Can't use 'duplicateExtensionInstanceFieldAndStaticSetter2' because it is declared more than once.
+//   Extension.duplicateExtensionInstanceFieldAndStaticSetter2 =
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:282:61: Error: Can't assign to this.
+//   Extension.duplicateExtensionInstanceFieldAndStaticSetter2 =
+//                                                             ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:287:13: Error: Can't use 'duplicateExtensionStaticFieldAndInstanceSetter1' because it is declared more than once.
+//   Extension.duplicateExtensionStaticFieldAndInstanceSetter1 =
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:288:17: Error: Can't use 'duplicateExtensionStaticFieldAndInstanceSetter1' because it is declared more than once.
+//       Extension.duplicateExtensionStaticFieldAndInstanceSetter1;
+//                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:287:61: Error: Can't assign to this.
+//   Extension.duplicateExtensionStaticFieldAndInstanceSetter1 =
+//                                                             ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:290:17: Error: Can't use 'duplicateExtensionStaticFieldAndInstanceSetter1' because it is declared more than once.
+//       Extension.duplicateExtensionStaticFieldAndInstanceSetter1;
+//                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:292:13: Error: Can't use 'duplicateExtensionStaticFieldAndInstanceSetter2' because it is declared more than once.
+//   Extension.duplicateExtensionStaticFieldAndInstanceSetter2 =
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:293:17: Error: Can't use 'duplicateExtensionStaticFieldAndInstanceSetter2' because it is declared more than once.
+//       Extension.duplicateExtensionStaticFieldAndInstanceSetter2;
+//                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:292:61: Error: Can't assign to this.
+//   Extension.duplicateExtensionStaticFieldAndInstanceSetter2 =
+//                                                             ^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:295:17: Error: Can't use 'duplicateExtensionStaticFieldAndInstanceSetter2' because it is declared more than once.
+//       Extension.duplicateExtensionStaticFieldAndInstanceSetter2;
+//                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:188:5: Error: Can't use 'duplicateInstanceFieldAndStaticSetter1' because it is declared more than once.
+//   c.duplicateInstanceFieldAndStaticSetter1 =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:189:9: Error: Can't use 'duplicateInstanceFieldAndStaticSetter1' because it is declared more than once.
+//       c.duplicateInstanceFieldAndStaticSetter1;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:189:9: Error: The getter 'duplicateInstanceFieldAndStaticSetter1' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'duplicateInstanceFieldAndStaticSetter1'.
+//       c.duplicateInstanceFieldAndStaticSetter1;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:188:5: Error: The setter 'duplicateInstanceFieldAndStaticSetter1' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateInstanceFieldAndStaticSetter1'.
+//   c.duplicateInstanceFieldAndStaticSetter1 =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:190:5: Error: Can't use 'duplicateInstanceFieldAndStaticSetter2' because it is declared more than once.
+//   c.duplicateInstanceFieldAndStaticSetter2 =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:191:9: Error: Can't use 'duplicateInstanceFieldAndStaticSetter2' because it is declared more than once.
+//       c.duplicateInstanceFieldAndStaticSetter2;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:191:9: Error: The getter 'duplicateInstanceFieldAndStaticSetter2' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'duplicateInstanceFieldAndStaticSetter2'.
+//       c.duplicateInstanceFieldAndStaticSetter2;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:190:5: Error: The setter 'duplicateInstanceFieldAndStaticSetter2' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateInstanceFieldAndStaticSetter2'.
+//   c.duplicateInstanceFieldAndStaticSetter2 =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:201:5: Error: The setter 'staticFieldAndInstanceSetter' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'staticFieldAndInstanceSetter'.
+//   c.staticFieldAndInstanceSetter = Class.staticFieldAndInstanceSetter;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:204:5: Error: The setter 'staticFieldAndInstanceDuplicateSetter' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'staticFieldAndInstanceDuplicateSetter'.
+//   c.staticFieldAndInstanceDuplicateSetter =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:217:5: Error: The setter 'duplicateStaticFieldAndInstanceSetter1' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateStaticFieldAndInstanceSetter1'.
+//   c.duplicateStaticFieldAndInstanceSetter1 =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:222:5: Error: The setter 'duplicateStaticFieldAndInstanceSetter2' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateStaticFieldAndInstanceSetter2'.
+//   c.duplicateStaticFieldAndInstanceSetter2 =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:232:41: Error: The getter 'extensionInstanceFieldAndSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'extensionInstanceFieldAndSetter'.
+//   0.extensionInstanceFieldAndSetter = 0.extensionInstanceFieldAndSetter;
+//                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:232:5: Error: The setter 'extensionInstanceFieldAndSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'extensionInstanceFieldAndSetter'.
+//   0.extensionInstanceFieldAndSetter = 0.extensionInstanceFieldAndSetter;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:234:9: Error: The getter 'extensionInstanceFieldAndDuplicateSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'extensionInstanceFieldAndDuplicateSetter'.
+//       0.extensionInstanceFieldAndDuplicateSetter;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:233:5: Error: The setter 'extensionInstanceFieldAndDuplicateSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'extensionInstanceFieldAndDuplicateSetter'.
+//   0.extensionInstanceFieldAndDuplicateSetter =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:237:9: Error: The getter 'duplicateExtensionInstanceFieldAndSetter1' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'duplicateExtensionInstanceFieldAndSetter1'.
+//       0.duplicateExtensionInstanceFieldAndSetter1;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:236:5: Error: The setter 'duplicateExtensionInstanceFieldAndSetter1' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateExtensionInstanceFieldAndSetter1'.
+//   0.duplicateExtensionInstanceFieldAndSetter1 =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:239:9: Error: The getter 'duplicateExtensionInstanceFieldAndSetter2' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'duplicateExtensionInstanceFieldAndSetter2'.
+//       0.duplicateExtensionInstanceFieldAndSetter2;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:238:5: Error: The setter 'duplicateExtensionInstanceFieldAndSetter2' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateExtensionInstanceFieldAndSetter2'.
+//   0.duplicateExtensionInstanceFieldAndSetter2 =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:257:5: Error: The setter 'extensionStaticFieldAndInstanceSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'extensionStaticFieldAndInstanceSetter'.
+//   0.extensionStaticFieldAndInstanceSetter =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:262:5: Error: The setter 'extensionStaticFieldAndInstanceDuplicateSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'extensionStaticFieldAndInstanceDuplicateSetter'.
+//   0.extensionStaticFieldAndInstanceDuplicateSetter =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:270:9: Error: The getter 'extensionInstanceFieldAndStaticSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'extensionInstanceFieldAndStaticSetter'.
+//       0.extensionInstanceFieldAndStaticSetter;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:269:5: Error: The setter 'extensionInstanceFieldAndStaticSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'extensionInstanceFieldAndStaticSetter'.
+//   0.extensionInstanceFieldAndStaticSetter =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:275:9: Error: The getter 'extensionInstanceFieldAndStaticDuplicateSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'extensionInstanceFieldAndStaticDuplicateSetter'.
+//       0.extensionInstanceFieldAndStaticDuplicateSetter;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:274:5: Error: The setter 'extensionInstanceFieldAndStaticDuplicateSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'extensionInstanceFieldAndStaticDuplicateSetter'.
+//   0.extensionInstanceFieldAndStaticDuplicateSetter =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:280:9: Error: The getter 'duplicateExtensionInstanceFieldAndStaticSetter1' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'duplicateExtensionInstanceFieldAndStaticSetter1'.
+//       0.duplicateExtensionInstanceFieldAndStaticSetter1;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:279:5: Error: The setter 'duplicateExtensionInstanceFieldAndStaticSetter1' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateExtensionInstanceFieldAndStaticSetter1'.
+//   0.duplicateExtensionInstanceFieldAndStaticSetter1 =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:285:9: Error: The getter 'duplicateExtensionInstanceFieldAndStaticSetter2' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'duplicateExtensionInstanceFieldAndStaticSetter2'.
+//       0.duplicateExtensionInstanceFieldAndStaticSetter2;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:284:5: Error: The setter 'duplicateExtensionInstanceFieldAndStaticSetter2' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateExtensionInstanceFieldAndStaticSetter2'.
+//   0.duplicateExtensionInstanceFieldAndStaticSetter2 =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:289:5: Error: The setter 'duplicateExtensionStaticFieldAndInstanceSetter1' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateExtensionStaticFieldAndInstanceSetter1'.
+//   0.duplicateExtensionStaticFieldAndInstanceSetter1 =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:294:5: Error: The setter 'duplicateExtensionStaticFieldAndInstanceSetter2' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateExtensionStaticFieldAndInstanceSetter2'.
+//   0.duplicateExtensionStaticFieldAndInstanceSetter2 =
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:39:14: Error: Final field 'duplicateInstanceFieldAndSetter2' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int? duplicateInstanceFieldAndSetter2 = null;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:61:21: Error: Final field 'duplicateStaticFieldAndSetter2' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   static final int? duplicateStaticFieldAndSetter2 = null;
+//                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:90:14: Error: Final field 'duplicateInstanceFieldAndStaticSetter2' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int? duplicateInstanceFieldAndStaticSetter2 = null;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/field_vs_setter.dart:98:21: Error: Final field 'duplicateStaticFieldAndInstanceSetter2' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   static final int? duplicateStaticFieldAndInstanceSetter2 = null;
+//                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int? instanceFieldAndSetter = null;
+  field core::int? instanceFieldAndDuplicateSetter = null;
+  field core::int? duplicateInstanceFieldAndSetter1 = null;
+  final field core::int? duplicateInstanceFieldAndSetter2 = null;
+  late final [setter] field core::int? instanceLateFinalFieldAndSetter;
+  late final [setter] field core::int? instanceLateFinalFieldAndDuplicateSetter;
+  static field core::int? staticFieldAndSetter = null;
+  static field core::int? staticFieldAndDuplicateSetter = null;
+  static field core::int? duplicateStaticFieldAndSetter1 = null;
+  static final field core::int? duplicateStaticFieldAndSetter2 = null;
+  late static final [setter] field core::int? staticLateFinalFieldAndSetter;
+  late static final [setter] field core::int? staticLateFinalFieldAndDuplicateSetter;
+  static field core::int? staticFieldAndInstanceSetter = null;
+  static field core::int? staticFieldAndInstanceDuplicateSetter = null;
+  field core::int? instanceFieldAndStaticSetter = null;
+  field core::int? instanceFieldAndStaticDuplicateSetter = null;
+  field core::int? duplicateInstanceFieldAndStaticSetter1 = null;
+  final field core::int? duplicateInstanceFieldAndStaticSetter2 = null;
+  static field core::int? duplicateStaticFieldAndInstanceSetter1 = null;
+  static final field core::int? duplicateStaticFieldAndInstanceSetter2 = null;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+}
+extension Extension on core::int? {
+  field extensionInstanceFieldAndSetter = self::Extension|extensionInstanceFieldAndSetter;
+  field extensionInstanceFieldAndDuplicateSetter = self::Extension|extensionInstanceFieldAndDuplicateSetter;
+  field duplicateExtensionInstanceFieldAndSetter1 = self::Extension|duplicateExtensionInstanceFieldAndSetter1;
+  field duplicateExtensionInstanceFieldAndSetter2 = self::Extension|duplicateExtensionInstanceFieldAndSetter2;
+  static field extensionStaticFieldAndSetter = self::Extension|extensionStaticFieldAndSetter;
+  static field extensionStaticFieldAndDuplicateSetter = self::Extension|extensionStaticFieldAndDuplicateSetter;
+  static field duplicateExtensionStaticFieldAndSetter1 = self::Extension|duplicateExtensionStaticFieldAndSetter1;
+  static field duplicateExtensionStaticFieldAndSetter2 = self::Extension|duplicateExtensionStaticFieldAndSetter2;
+  static field extensionStaticLateFinalFieldAndSetter = self::Extension|extensionStaticLateFinalFieldAndSetter;
+  static field extensionStaticLateFinalFieldAndDuplicateSetter = self::Extension|extensionStaticLateFinalFieldAndDuplicateSetter;
+  static field extensionStaticFieldAndInstanceSetter = self::Extension|extensionStaticFieldAndInstanceSetter;
+  static field extensionStaticFieldAndInstanceDuplicateSetter = self::Extension|extensionStaticFieldAndInstanceDuplicateSetter;
+  field extensionInstanceFieldAndStaticSetter = self::Extension|extensionInstanceFieldAndStaticSetter;
+  field extensionInstanceFieldAndStaticDuplicateSetter = self::Extension|extensionInstanceFieldAndStaticDuplicateSetter;
+  field duplicateExtensionInstanceFieldAndStaticSetter1 = self::Extension|duplicateExtensionInstanceFieldAndStaticSetter1;
+  field duplicateExtensionInstanceFieldAndStaticSetter2 = self::Extension|duplicateExtensionInstanceFieldAndStaticSetter2;
+  static field duplicateExtensionStaticFieldAndInstanceSetter1 = self::Extension|duplicateExtensionStaticFieldAndInstanceSetter1;
+  static field duplicateExtensionStaticFieldAndInstanceSetter2 = self::Extension|duplicateExtensionStaticFieldAndInstanceSetter2;
+}
+static field core::int? topLevelFieldAndSetter;
+static field core::int? topLevelFieldAndDuplicateSetter;
+static field core::int? duplicateTopLevelFieldAndSetter1;
+static final field core::int? duplicateTopLevelFieldAndSetter2;
+late static final [setter] field core::int? topLevelLateFinalFieldAndSetter;
+late static final [setter] field core::int? topLevelLateFinalFieldAndDuplicateSetter;
+static field core::int? Extension|extensionInstanceFieldAndSetter;
+static field core::int? Extension|extensionInstanceFieldAndDuplicateSetter;
+static field core::int? Extension|duplicateExtensionInstanceFieldAndSetter1;
+static final field core::int? Extension|duplicateExtensionInstanceFieldAndSetter2;
+static field core::int? Extension|extensionStaticFieldAndSetter;
+static field core::int? Extension|extensionStaticFieldAndDuplicateSetter;
+static field core::int? Extension|duplicateExtensionStaticFieldAndSetter1;
+static final field core::int? Extension|duplicateExtensionStaticFieldAndSetter2;
+late static final [setter] field core::int? Extension|extensionStaticLateFinalFieldAndSetter;
+late static final [setter] field core::int? Extension|extensionStaticLateFinalFieldAndDuplicateSetter;
+static field core::int? Extension|extensionStaticFieldAndInstanceSetter;
+static field core::int? Extension|extensionStaticFieldAndInstanceDuplicateSetter;
+static field core::int? Extension|extensionInstanceFieldAndStaticSetter;
+static field core::int? Extension|extensionInstanceFieldAndStaticDuplicateSetter;
+static field core::int? Extension|duplicateExtensionInstanceFieldAndStaticSetter1;
+static final field core::int? Extension|duplicateExtensionInstanceFieldAndStaticSetter2;
+static field core::int? Extension|duplicateExtensionStaticFieldAndInstanceSetter1;
+static final field core::int? Extension|duplicateExtensionStaticFieldAndInstanceSetter2;
+static const field dynamic _exports# = #C1 /*isLegacy*/;
+static method test() → dynamic {
+  self::topLevelFieldAndSetter = self::topLevelFieldAndSetter;
+  self::topLevelFieldAndDuplicateSetter = self::topLevelFieldAndDuplicateSetter;
+  self::topLevelLateFinalFieldAndSetter = self::topLevelLateFinalFieldAndSetter;
+  self::topLevelLateFinalFieldAndDuplicateSetter = self::topLevelLateFinalFieldAndDuplicateSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:178:36: Error: Can't assign to this.
+  duplicateTopLevelFieldAndSetter1 = duplicateTopLevelFieldAndSetter1;
+                                   ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:179:36: Error: Can't assign to this.
+  duplicateTopLevelFieldAndSetter2 = duplicateTopLevelFieldAndSetter2;
+                                   ^";
+  self::Class c = new self::Class::•();
+  c.{self::Class::instanceFieldAndSetter} = c.{self::Class::instanceFieldAndSetter}{core::int?};
+  c.{self::Class::instanceFieldAndDuplicateSetter} = c.{self::Class::instanceFieldAndDuplicateSetter}{core::int?};
+  c.{self::Class::instanceLateFinalFieldAndSetter} = c.{self::Class::instanceLateFinalFieldAndSetter}{core::int?};
+  c.{self::Class::instanceLateFinalFieldAndDuplicateSetter} = c.{self::Class::instanceLateFinalFieldAndDuplicateSetter}{core::int?};
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:188:5: Error: The setter 'duplicateInstanceFieldAndStaticSetter1' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateInstanceFieldAndStaticSetter1'.
+  c.duplicateInstanceFieldAndStaticSetter1 =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.duplicateInstanceFieldAndStaticSetter1 = invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:189:9: Error: The getter 'duplicateInstanceFieldAndStaticSetter1' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'duplicateInstanceFieldAndStaticSetter1'.
+      c.duplicateInstanceFieldAndStaticSetter1;
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.duplicateInstanceFieldAndStaticSetter1;
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:190:5: Error: The setter 'duplicateInstanceFieldAndStaticSetter2' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateInstanceFieldAndStaticSetter2'.
+  c.duplicateInstanceFieldAndStaticSetter2 =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.duplicateInstanceFieldAndStaticSetter2 = invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:191:9: Error: The getter 'duplicateInstanceFieldAndStaticSetter2' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'duplicateInstanceFieldAndStaticSetter2'.
+      c.duplicateInstanceFieldAndStaticSetter2;
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.duplicateInstanceFieldAndStaticSetter2;
+  self::Class::staticFieldAndSetter = self::Class::staticFieldAndSetter;
+  self::Class::staticFieldAndDuplicateSetter = self::Class::staticFieldAndDuplicateSetter;
+  self::Class::staticLateFinalFieldAndSetter = self::Class::staticLateFinalFieldAndSetter;
+  self::Class::staticLateFinalFieldAndDuplicateSetter = self::Class::staticLateFinalFieldAndDuplicateSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:198:40: Error: Can't assign to this.
+  Class.duplicateStaticFieldAndSetter1 = Class.duplicateStaticFieldAndSetter1;
+                                       ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:199:40: Error: Can't assign to this.
+  Class.duplicateStaticFieldAndSetter2 = Class.duplicateStaticFieldAndSetter2;
+                                       ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:201:5: Error: The setter 'staticFieldAndInstanceSetter' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'staticFieldAndInstanceSetter'.
+  c.staticFieldAndInstanceSetter = Class.staticFieldAndInstanceSetter;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.staticFieldAndInstanceSetter = self::Class::staticFieldAndInstanceSetter;
+  self::Class::staticFieldAndInstanceSetter = self::Class::staticFieldAndInstanceSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:204:5: Error: The setter 'staticFieldAndInstanceDuplicateSetter' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'staticFieldAndInstanceDuplicateSetter'.
+  c.staticFieldAndInstanceDuplicateSetter =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.staticFieldAndInstanceDuplicateSetter = self::Class::staticFieldAndInstanceDuplicateSetter;
+  self::Class::staticFieldAndInstanceDuplicateSetter = self::Class::staticFieldAndInstanceDuplicateSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:209:9: Error: Setter not found: 'instanceFieldAndStaticSetter'.
+  Class.instanceFieldAndStaticSetter = c.instanceFieldAndStaticSetter;
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+  c.{self::Class::instanceFieldAndStaticSetter} = c.{self::Class::instanceFieldAndStaticSetter}{core::int?};
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:212:47: Error: Can't assign to this.
+  Class.instanceFieldAndStaticDuplicateSetter =
+                                              ^";
+  c.{self::Class::instanceFieldAndStaticDuplicateSetter} = c.{self::Class::instanceFieldAndStaticDuplicateSetter}{core::int?};
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:217:5: Error: The setter 'duplicateStaticFieldAndInstanceSetter1' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateStaticFieldAndInstanceSetter1'.
+  c.duplicateStaticFieldAndInstanceSetter1 =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.duplicateStaticFieldAndInstanceSetter1 = invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:218:13: Error: Can't use 'duplicateStaticFieldAndInstanceSetter1' because it is declared more than once.
+      Class.duplicateStaticFieldAndInstanceSetter1;
+            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:219:48: Error: Can't assign to this.
+  Class.duplicateStaticFieldAndInstanceSetter1 =
+                                               ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:222:5: Error: The setter 'duplicateStaticFieldAndInstanceSetter2' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateStaticFieldAndInstanceSetter2'.
+  c.duplicateStaticFieldAndInstanceSetter2 =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.duplicateStaticFieldAndInstanceSetter2 = invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:223:13: Error: Can't use 'duplicateStaticFieldAndInstanceSetter2' because it is declared more than once.
+      Class.duplicateStaticFieldAndInstanceSetter2;
+            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:224:48: Error: Can't assign to this.
+  Class.duplicateStaticFieldAndInstanceSetter2 =
+                                               ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:227:48: Error: Can't assign to this.
+  Class.duplicateInstanceFieldAndStaticSetter1 =
+                                               ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:229:48: Error: Can't assign to this.
+  Class.duplicateInstanceFieldAndStaticSetter2 =
+                                               ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:232:5: Error: The setter 'extensionInstanceFieldAndSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'extensionInstanceFieldAndSetter'.
+  0.extensionInstanceFieldAndSetter = 0.extensionInstanceFieldAndSetter;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.extensionInstanceFieldAndSetter = invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:232:41: Error: The getter 'extensionInstanceFieldAndSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'extensionInstanceFieldAndSetter'.
+  0.extensionInstanceFieldAndSetter = 0.extensionInstanceFieldAndSetter;
+                                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.extensionInstanceFieldAndSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:233:5: Error: The setter 'extensionInstanceFieldAndDuplicateSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'extensionInstanceFieldAndDuplicateSetter'.
+  0.extensionInstanceFieldAndDuplicateSetter =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.extensionInstanceFieldAndDuplicateSetter = invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:234:9: Error: The getter 'extensionInstanceFieldAndDuplicateSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'extensionInstanceFieldAndDuplicateSetter'.
+      0.extensionInstanceFieldAndDuplicateSetter;
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.extensionInstanceFieldAndDuplicateSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:236:5: Error: The setter 'duplicateExtensionInstanceFieldAndSetter1' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateExtensionInstanceFieldAndSetter1'.
+  0.duplicateExtensionInstanceFieldAndSetter1 =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.duplicateExtensionInstanceFieldAndSetter1 = invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:237:9: Error: The getter 'duplicateExtensionInstanceFieldAndSetter1' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'duplicateExtensionInstanceFieldAndSetter1'.
+      0.duplicateExtensionInstanceFieldAndSetter1;
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.duplicateExtensionInstanceFieldAndSetter1;
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:238:5: Error: The setter 'duplicateExtensionInstanceFieldAndSetter2' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateExtensionInstanceFieldAndSetter2'.
+  0.duplicateExtensionInstanceFieldAndSetter2 =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.duplicateExtensionInstanceFieldAndSetter2 = invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:239:9: Error: The getter 'duplicateExtensionInstanceFieldAndSetter2' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'duplicateExtensionInstanceFieldAndSetter2'.
+      0.duplicateExtensionInstanceFieldAndSetter2;
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.duplicateExtensionInstanceFieldAndSetter2;
+  self::Extension|extensionStaticFieldAndSetter = self::Extension|extensionStaticFieldAndSetter;
+  self::Extension|extensionStaticFieldAndDuplicateSetter = self::Extension|extensionStaticFieldAndDuplicateSetter;
+  self::Extension|extensionStaticLateFinalFieldAndSetter = self::Extension|extensionStaticLateFinalFieldAndSetter;
+  self::Extension|extensionStaticLateFinalFieldAndDuplicateSetter = self::Extension|extensionStaticLateFinalFieldAndDuplicateSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:252:53: Error: Can't assign to this.
+  Extension.duplicateExtensionStaticFieldAndSetter1 =
+                                                    ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:254:53: Error: Can't assign to this.
+  Extension.duplicateExtensionStaticFieldAndSetter2 =
+                                                    ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:257:5: Error: The setter 'extensionStaticFieldAndInstanceSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'extensionStaticFieldAndInstanceSetter'.
+  0.extensionStaticFieldAndInstanceSetter =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.extensionStaticFieldAndInstanceSetter = self::Extension|extensionStaticFieldAndInstanceSetter;
+  self::Extension|extensionStaticFieldAndInstanceSetter = self::Extension|extensionStaticFieldAndInstanceSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:262:5: Error: The setter 'extensionStaticFieldAndInstanceDuplicateSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'extensionStaticFieldAndInstanceDuplicateSetter'.
+  0.extensionStaticFieldAndInstanceDuplicateSetter =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.extensionStaticFieldAndInstanceDuplicateSetter = self::Extension|extensionStaticFieldAndInstanceDuplicateSetter;
+  self::Extension|extensionStaticFieldAndInstanceDuplicateSetter = self::Extension|extensionStaticFieldAndInstanceDuplicateSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:267:13: Error: Setter not found: 'extensionInstanceFieldAndStaticSetter'.
+  Extension.extensionInstanceFieldAndStaticSetter =
+            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:269:5: Error: The setter 'extensionInstanceFieldAndStaticSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'extensionInstanceFieldAndStaticSetter'.
+  0.extensionInstanceFieldAndStaticSetter =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.extensionInstanceFieldAndStaticSetter = invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:270:9: Error: The getter 'extensionInstanceFieldAndStaticSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'extensionInstanceFieldAndStaticSetter'.
+      0.extensionInstanceFieldAndStaticSetter;
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.extensionInstanceFieldAndStaticSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:272:60: Error: Can't assign to this.
+  Extension.extensionInstanceFieldAndStaticDuplicateSetter =
+                                                           ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:274:5: Error: The setter 'extensionInstanceFieldAndStaticDuplicateSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'extensionInstanceFieldAndStaticDuplicateSetter'.
+  0.extensionInstanceFieldAndStaticDuplicateSetter =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.extensionInstanceFieldAndStaticDuplicateSetter = invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:275:9: Error: The getter 'extensionInstanceFieldAndStaticDuplicateSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'extensionInstanceFieldAndStaticDuplicateSetter'.
+      0.extensionInstanceFieldAndStaticDuplicateSetter;
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.extensionInstanceFieldAndStaticDuplicateSetter;
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:277:61: Error: Can't assign to this.
+  Extension.duplicateExtensionInstanceFieldAndStaticSetter1 =
+                                                            ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:279:5: Error: The setter 'duplicateExtensionInstanceFieldAndStaticSetter1' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateExtensionInstanceFieldAndStaticSetter1'.
+  0.duplicateExtensionInstanceFieldAndStaticSetter1 =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.duplicateExtensionInstanceFieldAndStaticSetter1 = invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:280:9: Error: The getter 'duplicateExtensionInstanceFieldAndStaticSetter1' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'duplicateExtensionInstanceFieldAndStaticSetter1'.
+      0.duplicateExtensionInstanceFieldAndStaticSetter1;
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.duplicateExtensionInstanceFieldAndStaticSetter1;
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:282:61: Error: Can't assign to this.
+  Extension.duplicateExtensionInstanceFieldAndStaticSetter2 =
+                                                            ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:284:5: Error: The setter 'duplicateExtensionInstanceFieldAndStaticSetter2' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateExtensionInstanceFieldAndStaticSetter2'.
+  0.duplicateExtensionInstanceFieldAndStaticSetter2 =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.duplicateExtensionInstanceFieldAndStaticSetter2 = invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:285:9: Error: The getter 'duplicateExtensionInstanceFieldAndStaticSetter2' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'duplicateExtensionInstanceFieldAndStaticSetter2'.
+      0.duplicateExtensionInstanceFieldAndStaticSetter2;
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.duplicateExtensionInstanceFieldAndStaticSetter2;
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:287:61: Error: Can't assign to this.
+  Extension.duplicateExtensionStaticFieldAndInstanceSetter1 =
+                                                            ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:289:5: Error: The setter 'duplicateExtensionStaticFieldAndInstanceSetter1' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateExtensionStaticFieldAndInstanceSetter1'.
+  0.duplicateExtensionStaticFieldAndInstanceSetter1 =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.duplicateExtensionStaticFieldAndInstanceSetter1 = invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:290:17: Error: Can't use 'duplicateExtensionStaticFieldAndInstanceSetter1' because it is declared more than once.
+      Extension.duplicateExtensionStaticFieldAndInstanceSetter1;
+                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:292:61: Error: Can't assign to this.
+  Extension.duplicateExtensionStaticFieldAndInstanceSetter2 =
+                                                            ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:294:5: Error: The setter 'duplicateExtensionStaticFieldAndInstanceSetter2' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'duplicateExtensionStaticFieldAndInstanceSetter2'.
+  0.duplicateExtensionStaticFieldAndInstanceSetter2 =
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.duplicateExtensionStaticFieldAndInstanceSetter2 = invalid-expression "pkg/front_end/testcases/nnbd/field_vs_setter.dart:295:17: Error: Can't use 'duplicateExtensionStaticFieldAndInstanceSetter2' because it is declared more than once.
+      Extension.duplicateExtensionStaticFieldAndInstanceSetter2;
+                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = "{\"topLevelFieldAndDuplicateSetter\":\"'topLevelFieldAndDuplicateSetter' is exported from both 'pkg/front_end/testcases/nnbd/field_vs_setter.dart' and 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.\",\"topLevelLateFinalFieldAndDuplicateSetter\":\"'topLevelLateFinalFieldAndDuplicateSetter' is exported from both 'pkg/front_end/testcases/nnbd/field_vs_setter.dart' and 'pkg/front_end/testcases/nnbd/field_vs_setter.dart'.\"}"
+}
diff --git a/pkg/front_end/testcases/nnbd/flutter_issue64155.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/flutter_issue64155.dart.weak.modular.expect
new file mode 100644
index 0000000..5ed98d4
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/flutter_issue64155.dart.weak.modular.expect
@@ -0,0 +1,77 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+abstract class TestMixin<R extends core::Object? = dynamic, T extends core::Object? = dynamic> extends core::Object /*isMixinDeclaration*/  {
+  method test(covariant-by-class asy::Future<self::TestMixin::R%> fetch) → asy::Future<self::TestMixin::T%> async {
+    final self::TestMixin::R% response = await fetch;
+    self::TestMixin::T% result;
+    if(response is{ForNonNullableByDefault} self::Response<dynamic>) {
+      result = response{self::TestMixin::R% & self::Response<dynamic> /* '%' & '!' = '!' */}.{self::Response::data}{dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} self::TestMixin::T%;
+    }
+    else
+      if(response is{ForNonNullableByDefault} self::PagingResponse<dynamic>) {
+        result = response{self::TestMixin::R% & self::PagingResponse<dynamic> /* '%' & '!' = '!' */}.{self::PagingResponse::data}{self::PagingResponseData<dynamic>}.{self::PagingResponseData::data}{core::List<dynamic>} as{ForNonNullableByDefault} self::TestMixin::T%;
+      }
+      else
+        if(response is{ForNonNullableByDefault} self::TestMixin::T%) {
+          result = response{self::TestMixin::R% & self::TestMixin::T% /* '%' & '%' = '%' */};
+        }
+        else {
+          throw core::Exception::•("Invalid response type");
+        }
+    return result;
+  }
+}
+class PagingResponse<T extends core::Object? = dynamic> extends core::Object {
+  final field self::PagingResponseData<self::PagingResponse::T%> data;
+  constructor •(self::PagingResponseData<self::PagingResponse::T%> data) → self::PagingResponse<self::PagingResponse::T%>
+    : self::PagingResponse::data = data, super core::Object::•()
+    ;
+}
+class PagingResponseData<T extends core::Object? = dynamic> extends core::Object {
+  final field core::List<self::PagingResponseData::T%> data;
+  constructor •(core::List<self::PagingResponseData::T%> data) → self::PagingResponseData<self::PagingResponseData::T%>
+    : self::PagingResponseData::data = data, super core::Object::•()
+    ;
+}
+class Response<T extends core::Object? = dynamic> extends core::Object {
+  final field self::Response::T% data;
+  constructor •(self::Response::T% data) → self::Response<self::Response::T%>
+    : self::Response::data = data, super core::Object::•()
+    ;
+}
+abstract class _Class1&Object&TestMixin = core::Object with self::TestMixin<self::Response<core::String>, core::String> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Class1&Object&TestMixin
+    : super core::Object::•()
+    ;
+  mixin-super-stub method test(covariant-by-class asy::Future<self::Response<core::String>> fetch) → asy::Future<core::String>
+    return super.{self::TestMixin::test}(fetch);
+}
+class Class1 extends self::_Class1&Object&TestMixin {
+  synthetic constructor •() → self::Class1
+    : super self::_Class1&Object&TestMixin::•()
+    ;
+  method _test() → dynamic {
+    final self::Response<core::String> response = new self::Response::•<core::String>("test");
+    this.{self::_Class1&Object&TestMixin::test}(asy::Future::value<self::Response<core::String>>(response)){(asy::Future<self::Response<core::String>>) → asy::Future<core::String>};
+  }
+}
+abstract class _Class2&Object&TestMixin = core::Object with self::TestMixin<self::PagingResponse<core::String>, core::String> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Class2&Object&TestMixin
+    : super core::Object::•()
+    ;
+  mixin-super-stub method test(covariant-by-class asy::Future<self::PagingResponse<core::String>> fetch) → asy::Future<core::String>
+    return super.{self::TestMixin::test}(fetch);
+}
+class Class2 extends self::_Class2&Object&TestMixin {
+  synthetic constructor •() → self::Class2
+    : super self::_Class2&Object&TestMixin::•()
+    ;
+  method _test() → dynamic {
+    final self::PagingResponse<core::String> response = new self::PagingResponse::•<core::String>(new self::PagingResponseData::•<core::String>(<core::String>["test"]));
+    this.{self::_Class2&Object&TestMixin::test}(asy::Future::value<self::PagingResponse<core::String>>(response)){(asy::Future<self::PagingResponse<core::String>>) → asy::Future<core::String>};
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/forbidden_supers.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/forbidden_supers.dart.weak.modular.expect
new file mode 100644
index 0000000..5fac846
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/forbidden_supers.dart.weak.modular.expect
@@ -0,0 +1,283 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:12:7: Error: Can't mix 'Aoo' in because it's marked with '?'.
+// class Coo extends Boo with Aoo? {}
+//       ^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:14:7: Error: Can't extend 'Aoo' because it's marked with '?'.
+// class Doo extends Aoo? {}
+//       ^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:16:7: Error: Can't implement 'Boo' because it's marked with '?'.
+// class Eoo implements Boo? {}
+//       ^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:18:7: Error: Can't extend 'Boo' because it's marked with '?'.
+// class Foo extends Boo? with Aoo {}
+//       ^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:20:7: Error: Can't extend 'Boo' because it's marked with '?'.
+// class Goo = Boo? with Aoo?;
+//       ^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:20:7: Error: Can't mix 'Aoo' in because it's marked with '?'.
+// class Goo = Boo? with Aoo?;
+//       ^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:22:7: Error: Can't implement 'Boo' because it's marked with '?'.
+// class Hoo extends Object with Aoo implements Boo? {}
+//       ^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:24:7: Error: Can't implement 'Boo' because it's marked with '?'.
+// class Ioo = Object with Aoo implements Boo?;
+//       ^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:32:7: Error: Can't extend 'Aoo' because it's marked with '?'.
+// mixin Moo1 on Aoo? implements Boo? {}
+//       ^^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:32:7: Error: Can't implement 'Boo' because it's marked with '?'.
+// mixin Moo1 on Aoo? implements Boo? {}
+//       ^^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:34:7: Error: Can't extend 'Aoo' because it's marked with '?'.
+// mixin Moo2 on Aoo?, Boo? {}
+//       ^^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:34:7: Error: Can't extend 'Boo' because it's marked with '?'.
+// mixin Moo2 on Aoo?, Boo? {}
+//       ^^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:36:7: Error: Can't implement 'Aoo' because it's marked with '?'.
+// mixin Moo3 implements Aoo?, Boo? {}
+//       ^^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:36:7: Error: Can't implement 'Boo' because it's marked with '?'.
+// mixin Moo3 implements Aoo?, Boo? {}
+//       ^^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:50:17: Error: Type 'void' can't be used here.
+// Try removing 'void' keyword or replace it with 'var', 'final', or a type.
+// class NooVoid = void with Aoo;
+//                 ^^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:50:17: Error: Type 'void' not found.
+// class NooVoid = void with Aoo;
+//                 ^^^^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:26:7: Error: The type 'Never' can't be mixed in.
+// class Joo extends Boo with Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:52:7: Error: The type 'Never' can't be mixed in.
+// class Ooo = Aoo with Never;
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:26:7: Error: The type 'Never' can't be used as supertype.
+// class Joo extends Boo with Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:28:7: Error: The type 'Never' can't be used as supertype.
+// class Koo extends Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:30:7: Error: The type 'Never' can't be used as supertype.
+// class Loo implements Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:38:7: Error: The type 'Never' can't be used as supertype.
+// mixin Moo4 on Aoo implements Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:40:7: Error: The type 'Never' can't be used as supertype.
+// mixin Moo5 on Aoo, Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:42:7: Error: The type 'Never' can't be used as supertype.
+// mixin Moo6 on Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:44:7: Error: The type 'Never' can't be used as supertype.
+// mixin Moo7 implements Aoo, Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:46:7: Error: The type 'Never' can't be used as supertype.
+// mixin Moo8 implements Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:48:7: Error: The type 'Never' can't be used as supertype.
+// class Noo = Never with Aoo;
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:49:7: Error: The type 'dynamic' can't be used as supertype.
+// class NooDynamic = dynamic with Aoo;
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:52:7: Error: The type 'Never' can't be used as supertype.
+// class Ooo = Aoo with Never;
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:28:7: Error: The type 'Never' can't be used in an 'extends' clause.
+// class Koo extends Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:30:7: Error: The type 'Never' can't be used in an 'implements' clause.
+// class Loo implements Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:38:7: Error: The type 'Never' can't be used in an 'implements' clause.
+// mixin Moo4 on Aoo implements Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:40:7: Error: The type 'Never' can't be used in an 'implements' clause.
+// mixin Moo5 on Aoo, Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:42:7: Error: The type 'Never' can't be used in an 'extends' clause.
+// mixin Moo6 on Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:44:7: Error: The type 'Never' can't be used in an 'implements' clause.
+// mixin Moo7 implements Aoo, Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:46:7: Error: The type 'Never' can't be used in an 'implements' clause.
+// mixin Moo8 implements Never {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/forbidden_supers.dart:48:7: Error: The type 'Never' can't be used in an 'extends' clause.
+// class Noo = Never with Aoo;
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Aoo extends core::Object {
+  synthetic constructor •() → self::Aoo
+    : super core::Object::•()
+    ;
+}
+class Boo extends core::Object {
+  synthetic constructor •() → self::Boo
+    : super core::Object::•()
+    ;
+}
+abstract class _Coo&Boo&Aoo = self::Boo with self::Aoo /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Coo&Boo&Aoo
+    : super self::Boo::•()
+    ;
+}
+class Coo extends self::_Coo&Boo&Aoo {
+  synthetic constructor •() → self::Coo
+    : super self::_Coo&Boo&Aoo::•()
+    ;
+}
+class Doo extends self::Aoo {
+  synthetic constructor •() → self::Doo
+    : super self::Aoo::•()
+    ;
+}
+class Eoo extends core::Object implements self::Boo {
+  synthetic constructor •() → self::Eoo
+    : super core::Object::•()
+    ;
+}
+abstract class _Foo&Boo&Aoo = self::Boo with self::Aoo /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Foo&Boo&Aoo
+    : super self::Boo::•()
+    ;
+}
+class Foo extends self::_Foo&Boo&Aoo {
+  synthetic constructor •() → self::Foo
+    : super self::_Foo&Boo&Aoo::•()
+    ;
+}
+class Goo = self::Boo with self::Aoo {
+  synthetic constructor •() → self::Goo
+    : super self::Boo::•()
+    ;
+}
+abstract class _Hoo&Object&Aoo = core::Object with self::Aoo /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Hoo&Object&Aoo
+    : super core::Object::•()
+    ;
+}
+class Hoo extends self::_Hoo&Object&Aoo implements self::Boo {
+  synthetic constructor •() → self::Hoo
+    : super self::_Hoo&Object&Aoo::•()
+    ;
+}
+class Ioo = core::Object with self::Aoo implements self::Boo /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::Ioo
+    : super core::Object::•()
+    ;
+}
+abstract class _Joo&Boo&Never extends self::Boo /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Joo&Boo&Never
+    : super self::Boo::•()
+    ;
+}
+class Joo extends self::_Joo&Boo&Never {
+  synthetic constructor •() → self::Joo
+    : super self::_Joo&Boo&Never::•()
+    ;
+}
+class Koo extends core::Object {
+  synthetic constructor •() → self::Koo
+    : super core::Object::•()
+    ;
+}
+class Loo extends core::Object {
+  synthetic constructor •() → self::Loo
+    : super core::Object::•()
+    ;
+}
+abstract class Moo1 extends self::Aoo implements self::Boo /*isMixinDeclaration*/  {
+}
+abstract class _Moo2&Aoo&Boo extends core::Object implements self::Aoo, self::Boo /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Moo2&Aoo&Boo
+    : super core::Object::•()
+    ;
+}
+abstract class Moo2 extends self::_Moo2&Aoo&Boo /*isMixinDeclaration*/  {
+}
+abstract class Moo3 extends core::Object implements self::Aoo, self::Boo /*isMixinDeclaration*/  {
+}
+abstract class Moo4 extends self::Aoo /*isMixinDeclaration*/  {
+}
+abstract class _Moo5&Aoo&Never extends core::Object implements self::Aoo /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Moo5&Aoo&Never
+    : super core::Object::•()
+    ;
+}
+abstract class Moo5 extends self::_Moo5&Aoo&Never /*isMixinDeclaration*/  {
+}
+abstract class Moo6 extends core::Object /*isMixinDeclaration*/  {
+}
+abstract class Moo7 extends core::Object implements self::Aoo /*isMixinDeclaration*/  {
+}
+abstract class Moo8 extends core::Object /*isMixinDeclaration*/  {
+}
+class Noo = core::Object with self::Aoo {
+  synthetic constructor •() → self::Noo
+    : super core::Object::•()
+    ;
+}
+class NooDynamic = core::Object with self::Aoo {
+  synthetic constructor •() → self::NooDynamic
+    : super core::Object::•()
+    ;
+}
+class NooVoid = core::Object with self::Aoo {
+  synthetic constructor •() → self::NooVoid
+    : super core::Object::•()
+    ;
+}
+class Ooo extends self::Aoo {
+  synthetic constructor •() → self::Ooo
+    : super self::Aoo::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/forin.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/forin.dart.weak.modular.expect
new file mode 100644
index 0000000..875fe7a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/forin.dart.weak.modular.expect
@@ -0,0 +1,149 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/forin.dart:9:17: Error: The type 'Iterable<int>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'Iterable<int>?' is nullable and 'Iterable<dynamic>' isn't.
+//  - 'Iterable' is from 'dart:core'.
+//   for (int x in i2) x;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/forin.dart:10:18: Error: The type 'Iterable<int>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'Iterable<int>?' is nullable and 'Iterable<dynamic>' isn't.
+//  - 'Iterable' is from 'dart:core'.
+//   [for (int x in i2) x];
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/forin.dart:12:17: Error: The type 'List<int>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'List<int>?' is nullable and 'Iterable<dynamic>' isn't.
+//  - 'List' is from 'dart:core'.
+//  - 'Iterable' is from 'dart:core'.
+//   for (int x in l2) x;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/forin.dart:13:18: Error: The type 'List<int>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'List<int>?' is nullable and 'Iterable<dynamic>' isn't.
+//  - 'List' is from 'dart:core'.
+//  - 'Iterable' is from 'dart:core'.
+//   [for (int x in l2) x];
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/forin.dart:15:17: Error: The type 'Object' used in the 'for' loop must implement 'Iterable<dynamic>'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Iterable' is from 'dart:core'.
+//   for (int x in o1) x;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/forin.dart:16:18: Error: The type 'Object' used in the 'for' loop must implement 'Iterable<dynamic>'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Iterable' is from 'dart:core'.
+//   [for (int x in o1) x];
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/forin.dart:18:17: Error: The type 'Object?' used in the 'for' loop must implement 'Iterable<dynamic>'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Iterable' is from 'dart:core'.
+//   for (int x in o2) x;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/forin.dart:19:18: Error: The type 'Object?' used in the 'for' loop must implement 'Iterable<dynamic>'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Iterable' is from 'dart:core'.
+//   [for (int x in o2) x];
+//                  ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method error(core::Iterable<core::int>? i2, core::List<core::int>? l2, core::Object o1, core::Object? o2) → dynamic {
+  for (core::int x in invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:9:17: Error: The type 'Iterable<int>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'Iterable<int>?' is nullable and 'Iterable<dynamic>' isn't.
+ - 'Iterable' is from 'dart:core'.
+  for (int x in i2) x;
+                ^" in i2 as{TypeError,ForNonNullableByDefault} core::Iterable<dynamic>)
+    x;
+  block {
+    final core::List<core::int> #t1 = <core::int>[];
+    for (core::int x in invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:10:18: Error: The type 'Iterable<int>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'Iterable<int>?' is nullable and 'Iterable<dynamic>' isn't.
+ - 'Iterable' is from 'dart:core'.
+  [for (int x in i2) x];
+                 ^" in i2 as{TypeError,ForNonNullableByDefault} core::Iterable<dynamic>)
+      #t1.{core::List::add}{Invariant}(x){(core::int) → void};
+  } =>#t1;
+  for (core::int x in invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:12:17: Error: The type 'List<int>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'List<int>?' is nullable and 'Iterable<dynamic>' isn't.
+ - 'List' is from 'dart:core'.
+ - 'Iterable' is from 'dart:core'.
+  for (int x in l2) x;
+                ^" in l2 as{TypeError,ForNonNullableByDefault} core::Iterable<dynamic>)
+    x;
+  block {
+    final core::List<core::int> #t2 = <core::int>[];
+    for (core::int x in invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:13:18: Error: The type 'List<int>?' used in the 'for' loop must implement 'Iterable<dynamic>' because 'List<int>?' is nullable and 'Iterable<dynamic>' isn't.
+ - 'List' is from 'dart:core'.
+ - 'Iterable' is from 'dart:core'.
+  [for (int x in l2) x];
+                 ^" in l2 as{TypeError,ForNonNullableByDefault} core::Iterable<dynamic>)
+      #t2.{core::List::add}{Invariant}(x){(core::int) → void};
+  } =>#t2;
+  for (final dynamic #t3 in invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:15:17: Error: The type 'Object' used in the 'for' loop must implement 'Iterable<dynamic>'.
+ - 'Object' is from 'dart:core'.
+ - 'Iterable' is from 'dart:core'.
+  for (int x in o1) x;
+                ^" in o1 as{TypeError,ForNonNullableByDefault} core::Iterable<dynamic>) {
+    core::int x = #t3 as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+    x;
+  }
+  block {
+    final core::List<core::int> #t4 = <core::int>[];
+    for (final dynamic #t5 in invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:16:18: Error: The type 'Object' used in the 'for' loop must implement 'Iterable<dynamic>'.
+ - 'Object' is from 'dart:core'.
+ - 'Iterable' is from 'dart:core'.
+  [for (int x in o1) x];
+                 ^" in o1 as{TypeError,ForNonNullableByDefault} core::Iterable<dynamic>) {
+      core::int x = #t5 as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+      #t4.{core::List::add}{Invariant}(x){(core::int) → void};
+    }
+  } =>#t4;
+  for (final dynamic #t6 in invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:18:17: Error: The type 'Object?' used in the 'for' loop must implement 'Iterable<dynamic>'.
+ - 'Object' is from 'dart:core'.
+ - 'Iterable' is from 'dart:core'.
+  for (int x in o2) x;
+                ^" in o2 as{TypeError,ForNonNullableByDefault} core::Iterable<dynamic>) {
+    core::int x = #t6 as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+    x;
+  }
+  block {
+    final core::List<core::int> #t7 = <core::int>[];
+    for (final dynamic #t8 in invalid-expression "pkg/front_end/testcases/nnbd/forin.dart:19:18: Error: The type 'Object?' used in the 'for' loop must implement 'Iterable<dynamic>'.
+ - 'Object' is from 'dart:core'.
+ - 'Iterable' is from 'dart:core'.
+  [for (int x in o2) x];
+                 ^" in o2 as{TypeError,ForNonNullableByDefault} core::Iterable<dynamic>) {
+      core::int x = #t8 as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+      #t7.{core::List::add}{Invariant}(x){(core::int) → void};
+    }
+  } =>#t7;
+}
+static method ok(core::Iterable<core::int> i1, core::List<core::int> l1, dynamic d) → dynamic {
+  for (core::int x in i1)
+    x;
+  block {
+    final core::List<core::int> #t9 = <core::int>[];
+    for (core::int x in i1)
+      #t9.{core::List::add}{Invariant}(x){(core::int) → void};
+  } =>#t9;
+  for (core::int x in l1)
+    x;
+  block {
+    final core::List<core::int> #t10 = <core::int>[];
+    for (core::int x in l1)
+      #t10.{core::List::add}{Invariant}(x){(core::int) → void};
+  } =>#t10;
+  for (final dynamic #t11 in d as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>) {
+    core::int x = #t11 as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+    x;
+  }
+  block {
+    final core::List<core::int> #t12 = <core::int>[];
+    for (final dynamic #t13 in d as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>) {
+      core::int x = #t13 as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+      #t12.{core::List::add}{Invariant}(x){(core::int) → void};
+    }
+  } =>#t12;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/from_agnostic/from_agnostic.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/from_agnostic/from_agnostic.dart.weak.modular.expect
new file mode 100644
index 0000000..5118ed8
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/from_agnostic/from_agnostic.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///from_agnostic_lib.dart";
+
+static const field core::bool c1 = #C1;
+static const field core::Map<core::List<core::int?>, core::int> c2 = #C6;
+static const field core::Set<core::List<core::int?>> c3 = #C7;
+static const field core::List<core::int> c4 = #C2;
+static const field core::List<core::int?> c5 = #C4;
+static method main() → dynamic {
+  #C2;
+  #C4;
+}
+
+constants  {
+  #C1 = false
+  #C2 = <core::int*>[]
+  #C3 = 0
+  #C4 = <core::int?>[]
+  #C5 = 1
+  #C6 = <core::List<core::int?>*, core::int*>{#C2:#C3, #C4:#C5)
+  #C7 = <core::List<core::int?>*>{#C2, #C4}
+}
diff --git a/pkg/front_end/testcases/nnbd/function_types.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/function_types.dart.weak.modular.expect
new file mode 100644
index 0000000..57a3b98
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/function_types.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef F = () → void;
+class A<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+}
+class B extends self::A<() →? dynamic> {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+  method method(() →? dynamic x) → () →? dynamic
+    return null;
+}
+static method foo() → void {}
+static method bar() → () → void
+  return #C1;
+static method baz() → () →? void
+  return #C1;
+static method hest() → () → void
+  return #C1;
+static method fisk() → () →? void
+  return #C1;
+static method foobar(() →? dynamic x) → () →? dynamic
+  return null;
+static method main() → dynamic {
+  () → void g = () → void {};
+  () →? void f = g;
+  () → void fBar = self::bar();
+  () →? void fBaz = self::baz();
+  () → void fHest = self::hest();
+  () →? void fFisk = self::fisk();
+}
+
+constants  {
+  #C1 = static-tearoff self::foo
+}
diff --git a/pkg/front_end/testcases/nnbd/future_or_variables.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/future_or_variables.dart.weak.modular.expect
new file mode 100644
index 0000000..88659fb
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/future_or_variables.dart.weak.modular.expect
@@ -0,0 +1,51 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+class Class1 extends core::Object {
+  field FutureOr<dynamic>instanceField1 = null;
+  field FutureOr<core::int?>instanceField2 = null;
+  field FutureOr<FutureOr<dynamic>>instanceField3 = null;
+  static field FutureOr<dynamic>staticField1 = null;
+  static field FutureOr<core::int?>staticField2 = null;
+  static field FutureOr<FutureOr<dynamic>>staticField3 = null;
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+  method instanceMethod1([FutureOr<dynamic>parameter1 = #C1, FutureOr<core::int?>parameter2 = #C1, FutureOr<FutureOr<dynamic>>parameter3 = #C1]) → void {}
+  method instanceMethod2({FutureOr<dynamic>parameter1 = #C1, FutureOr<core::int?>parameter2 = #C1, FutureOr<FutureOr<dynamic>>parameter3 = #C1}) → void {}
+  static method staticMethod1([FutureOr<dynamic>parameter1 = #C1, FutureOr<core::int?>parameter2 = #C1, FutureOr<FutureOr<dynamic>>parameter3 = #C1]) → void {}
+  static method staticMethod2({FutureOr<dynamic>parameter1 = #C1, FutureOr<core::int?>parameter2 = #C1, FutureOr<FutureOr<dynamic>>parameter3 = #C1}) → void {}
+}
+class Class2 extends core::Object {
+  field FutureOr<dynamic>instanceField1;
+  field FutureOr<core::int?>instanceField2;
+  field FutureOr<FutureOr<dynamic>>instanceField3;
+  constructor constructor1(FutureOr<dynamic>instanceField1, FutureOr<core::int?>instanceField2, FutureOr<FutureOr<dynamic>>instanceField3) → self::Class2
+    : self::Class2::instanceField1 = instanceField1, self::Class2::instanceField2 = instanceField2, self::Class2::instanceField3 = instanceField3, super core::Object::•()
+    ;
+  constructor constructor2() → self::Class2
+    : self::Class2::instanceField3 = null, self::Class2::instanceField2 = null, self::Class2::instanceField1 = null, super core::Object::•()
+    ;
+}
+static field FutureOr<dynamic>topLevelField1;
+static field FutureOr<core::int?>topLevelField2;
+static field FutureOr<FutureOr<dynamic>>topLevelField3;
+static method toplevelMethod1([FutureOr<dynamic>parameter1 = #C1, FutureOr<core::int?>parameter2 = #C1, FutureOr<FutureOr<dynamic>>parameter3 = #C1]) → void {}
+static method toplevelMethod2({FutureOr<dynamic>parameter1 = #C1, FutureOr<core::int?>parameter2 = #C1, FutureOr<FutureOr<dynamic>>parameter3 = #C1}) → void {}
+static method main() → dynamic {
+  FutureOr<dynamic>local1;
+  FutureOr<core::int?>local2;
+  FutureOr<FutureOr<dynamic>>local3;
+  core::print(local1);
+  core::print(local2);
+  core::print(local3);
+  function localFunction1([FutureOr<dynamic>parameter1 = #C1, FutureOr<core::int?>parameter2 = #C1, FutureOr<FutureOr<dynamic>>parameter3 = #C1]) → void {}
+  function localFunction2({FutureOr<dynamic>parameter1 = #C1, FutureOr<core::int?>parameter2 = #C1, FutureOr<FutureOr<dynamic>>parameter3 = #C1}) → void {}
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart.weak.modular.expect
new file mode 100644
index 0000000..c796a15
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart.weak.modular.expect
@@ -0,0 +1,273 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:21:11: Error: The type 'num' of the getter 'A.property3' is not a subtype of the type 'int' of the setter 'A.property3'.
+//   num get property3; // error
+//           ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:22:12: Context: This is the declaration of the setter 'A.property3'.
+//   void set property3(int i);
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:36:18: Error: The type 'num' of the getter 'A.property9' is not a subtype of the type 'int' of the setter 'A.property9'.
+//   static num get property9 => 0; // error
+//                  ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:37:19: Context: This is the declaration of the setter 'A.property9'.
+//   static void set property9(int value) {}
+//                   ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:61:12: Error: The type 'num' of the inherited getter 'B1.property3' is not a subtype of the type 'int' of the setter 'B2.property3'.
+//   void set property3(int i); // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:45:11: Context: This is the declaration of the getter 'B1.property3'.
+//   num get property3;
+//           ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:67:12: Error: The type 'num' of the inherited field 'B1.property6' is not a subtype of the type 'int' of the setter 'B2.property6'.
+//   void set property6(int i); // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:51:13: Context: This is the declaration of the field 'B1.property6'.
+//   final num property6;
+//             ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:89:11: Error: The type 'num' of the getter 'C2.property3' is not a subtype of the type 'int' of the inherited setter 'C1.property3'.
+//   num get property3; // error
+//           ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:75:12: Context: This is the declaration of the setter 'C1.property3'.
+//   void set property3(int i);
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:97:11: Error: The type 'num' of the getter 'C2.property6' is not a subtype of the type 'int' of the inherited setter 'C1.property6'.
+//   num get property6; // error
+//           ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:81:7: Context: This is the declaration of the setter 'C1.property6'.
+//   int property6 = 0;
+//       ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:97:11: Error: The return type of the method 'C2.property6' is 'num', which does not match the return type, 'int', of the overridden method, 'C1.property6'.
+// Change to a subtype of 'int'.
+//   num get property6; // error
+//           ^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:81:7: Context: This is the overridden method ('property6').
+//   int property6 = 0;
+//       ^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:116:16: Error: The type 'num' of the inherited getter 'D1.property3' is not a subtype of the type 'int' of the inherited setter 'D2.property3'.
+// abstract class D3 implements D1, D2 /* error on property3 */ {}
+//                ^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:105:11: Context: This is the declaration of the getter 'D1.property3'.
+//   num get property3;
+//           ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:113:12: Context: This is the declaration of the setter 'D2.property3'.
+//   void set property3(int i);
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:118:16: Error: The type 'num' of the inherited getter 'D1.property3' is not a subtype of the type 'int' of the inherited setter 'D2.property3'.
+// abstract class D4 implements D3 /* no need for error on property3 */ {}
+//                ^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:105:11: Context: This is the declaration of the getter 'D1.property3'.
+//   num get property3;
+//           ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:113:12: Context: This is the declaration of the setter 'D2.property3'.
+//   void set property3(int i);
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:11:9: Error: The type 'num' of the getter 'property3' is not a subtype of the type 'int' of the setter 'property3'.
+// num get property3 => 0; // error
+//         ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:12:10: Context: This is the declaration of the setter 'property3'.
+// void set property3(int value) {}
+//          ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:127:11: Error: The type 'num' of the getter 'property3' is not a subtype of the type 'int' of the setter 'property3'.
+//   num get property3 => 0; // error
+//           ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:128:12: Context: This is the declaration of the setter 'property3'.
+//   void set property3(int i) {}
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:136:9: Error: The type 'T' of the getter 'property6' is not a subtype of the type 'S' of the setter 'property6'.
+//   T get property6 => 0; // error
+//         ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:137:12: Context: This is the declaration of the setter 'property6'.
+//   void set property6(S i) {}
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:145:18: Error: The type 'num' of the getter 'property9' is not a subtype of the type 'int' of the setter 'property9'.
+//   static num get property9 => 0; // error
+//                  ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:146:19: Context: This is the declaration of the setter 'property9'.
+//   static void set property9(int value) {}
+//                   ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:130:22: Error: A value of type 'int' can't be returned from a function with return type 'S'.
+//   S get property4 => 0; // ok
+//                      ^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:133:22: Error: A value of type 'int' can't be returned from a function with return type 'S'.
+//   S get property5 => 0; // ok
+//                      ^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:136:22: Error: A value of type 'int' can't be returned from a function with return type 'T'.
+//   T get property6 => 0; // error
+//                      ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  field core::int property4 = 0;
+  field core::int property5 = 0;
+  covariant-by-declaration field core::num property6 = 0;
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  abstract get property1() → core::int;
+  abstract set property1(core::int i) → void;
+  abstract get property2() → core::int;
+  abstract set property2(core::int i) → void;
+  abstract get property3() → core::num;
+  abstract set property3(core::int i) → void;
+  static get property7() → core::int
+    return 0;
+  static set property7(core::int value) → void {}
+  static get property8() → core::int
+    return 0;
+  static set property8(core::num value) → void {}
+  static get property9() → core::num
+    return 0;
+  static set property9(core::int value) → void {}
+}
+abstract class B1 extends core::Object {
+  final field core::int property4;
+  final field core::int property5;
+  final field core::num property6;
+  constructor •(core::int property4, core::int property5, core::num property6) → self::B1
+    : self::B1::property4 = property4, self::B1::property5 = property5, self::B1::property6 = property6, super core::Object::•()
+    ;
+  abstract get property1() → core::int;
+  abstract get property2() → core::int;
+  abstract get property3() → core::num;
+}
+abstract class B2 extends core::Object implements self::B1 {
+  synthetic constructor •() → self::B2
+    : super core::Object::•()
+    ;
+  abstract set property1(core::int i) → void;
+  abstract set property2(core::num i) → void;
+  abstract set property3(core::int i) → void;
+  abstract set property4(core::int i) → void;
+  abstract set property5(core::num i) → void;
+  abstract set property6(core::int i) → void;
+}
+abstract class C1 extends core::Object {
+  field core::int property4 = 0;
+  field core::num property5 = 0;
+  field core::int property6 = 0;
+  synthetic constructor •() → self::C1
+    : super core::Object::•()
+    ;
+  abstract set property1(core::int i) → void;
+  abstract set property2(core::num i) → void;
+  abstract set property3(core::int i) → void;
+}
+abstract class C2 extends core::Object implements self::C1 {
+  synthetic constructor •() → self::C2
+    : super core::Object::•()
+    ;
+  abstract get property1() → core::int;
+  abstract get property2() → core::int;
+  abstract get property3() → core::num;
+  abstract get property4() → core::int;
+  abstract get property5() → core::int;
+  abstract get property6() → core::num;
+}
+abstract class D1 extends core::Object {
+  synthetic constructor •() → self::D1
+    : super core::Object::•()
+    ;
+  abstract get property1() → core::int;
+  abstract get property2() → core::int;
+  abstract get property3() → core::num;
+}
+abstract class D2 extends core::Object {
+  synthetic constructor •() → self::D2
+    : super core::Object::•()
+    ;
+  abstract set property1(core::int i) → void;
+  abstract set property2(core::num i) → void;
+  abstract set property3(core::int i) → void;
+}
+abstract class D3 extends core::Object implements self::D1, self::D2 {
+  synthetic constructor •() → self::D3
+    : super core::Object::•()
+    ;
+}
+abstract class D4 extends core::Object implements self::D3 {
+  synthetic constructor •() → self::D4
+    : super core::Object::•()
+    ;
+}
+extension Extension<T extends core::Object? = dynamic, S extends T% = dynamic> on core::int {
+  get property1 = self::Extension|get#property1;
+  get property2 = self::Extension|get#property2;
+  get property3 = self::Extension|get#property3;
+  get property4 = self::Extension|get#property4;
+  get property5 = self::Extension|get#property5;
+  get property6 = self::Extension|get#property6;
+  static get property7 = get self::Extension|property7;
+  static get property8 = get self::Extension|property8;
+  static get property9 = get self::Extension|property9;
+  set property1 = self::Extension|set#property1;
+  set property2 = self::Extension|set#property2;
+  set property3 = self::Extension|set#property3;
+  set property4 = self::Extension|set#property4;
+  set property5 = self::Extension|set#property5;
+  set property6 = self::Extension|set#property6;
+  static set property7 = set self::Extension|property7;
+  static set property8 = set self::Extension|property8;
+  static set property9 = set self::Extension|property9;
+}
+static get property1() → core::int
+  return 0;
+static set property1(core::int value) → void {}
+static get property2() → core::int
+  return 0;
+static set property2(core::num value) → void {}
+static get property3() → core::num
+  return 0;
+static set property3(core::int value) → void {}
+static method Extension|get#property1<T extends core::Object? = dynamic, S extends self::Extension|get#property1::T% = dynamic>(lowered final core::int #this) → core::int
+  return 0;
+static method Extension|set#property1<T extends core::Object? = dynamic, S extends self::Extension|set#property1::T% = dynamic>(lowered final core::int #this, core::int i) → void {}
+static method Extension|get#property2<T extends core::Object? = dynamic, S extends self::Extension|get#property2::T% = dynamic>(lowered final core::int #this) → core::int
+  return 0;
+static method Extension|set#property2<T extends core::Object? = dynamic, S extends self::Extension|set#property2::T% = dynamic>(lowered final core::int #this, core::num i) → void {}
+static method Extension|get#property3<T extends core::Object? = dynamic, S extends self::Extension|get#property3::T% = dynamic>(lowered final core::int #this) → core::num
+  return 0;
+static method Extension|set#property3<T extends core::Object? = dynamic, S extends self::Extension|set#property3::T% = dynamic>(lowered final core::int #this, core::int i) → void {}
+static method Extension|get#property4<T extends core::Object? = dynamic, S extends self::Extension|get#property4::T% = dynamic>(lowered final core::int #this) → self::Extension|get#property4::S%
+  return invalid-expression "pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:130:22: Error: A value of type 'int' can't be returned from a function with return type 'S'.
+  S get property4 => 0; // ok
+                     ^" in 0 as{TypeError,ForNonNullableByDefault} Never;
+static method Extension|set#property4<T extends core::Object? = dynamic, S extends self::Extension|set#property4::T% = dynamic>(lowered final core::int #this, self::Extension|set#property4::S% i) → void {}
+static method Extension|get#property5<T extends core::Object? = dynamic, S extends self::Extension|get#property5::T% = dynamic>(lowered final core::int #this) → self::Extension|get#property5::S%
+  return invalid-expression "pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:133:22: Error: A value of type 'int' can't be returned from a function with return type 'S'.
+  S get property5 => 0; // ok
+                     ^" in 0 as{TypeError,ForNonNullableByDefault} Never;
+static method Extension|set#property5<T extends core::Object? = dynamic, S extends self::Extension|set#property5::T% = dynamic>(lowered final core::int #this, self::Extension|set#property5::T% i) → void {}
+static method Extension|get#property6<T extends core::Object? = dynamic, S extends self::Extension|get#property6::T% = dynamic>(lowered final core::int #this) → self::Extension|get#property6::T%
+  return invalid-expression "pkg/front_end/testcases/nnbd/getter_vs_setter_type.dart:136:22: Error: A value of type 'int' can't be returned from a function with return type 'T'.
+  T get property6 => 0; // error
+                     ^" in 0 as{TypeError,ForNonNullableByDefault} Never;
+static method Extension|set#property6<T extends core::Object? = dynamic, S extends self::Extension|set#property6::T% = dynamic>(lowered final core::int #this, self::Extension|set#property6::S% i) → void {}
+static get Extension|property7() → core::int
+  return 0;
+static set Extension|property7(core::int value) → void {}
+static get Extension|property8() → core::int
+  return 0;
+static set Extension|property8(core::num value) → void {}
+static get Extension|property9() → core::num
+  return 0;
+static set Extension|property9(core::int value) → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/getter_vs_setter_type_late.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/getter_vs_setter_type_late.dart.weak.modular.expect
new file mode 100644
index 0000000..6234f7f
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/getter_vs_setter_type_late.dart.weak.modular.expect
@@ -0,0 +1,70 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_late.dart:30:12: Error: The type 'int?' of the inherited field 'B1.property6' is not a subtype of the type 'int' of the setter 'B2.property6'.
+//   void set property6(int i); // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_late.dart:20:19: Context: This is the declaration of the field 'B1.property6'.
+//   late final int? property6;
+//                   ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_late.dart:50:12: Error: The type 'int?' of the getter 'C2.property6' is not a subtype of the type 'int' of the inherited setter 'C1.property6'.
+//   int? get property6; // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_late.dart:38:12: Context: This is the declaration of the setter 'C1.property6'.
+//   late int property6;
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_late.dart:50:12: Error: The return type of the method 'C2.property6' is 'int?', which does not match the return type, 'int', of the overridden method, 'C1.property6'.
+// Change to a subtype of 'int'.
+//   int? get property6; // error
+//            ^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_late.dart:38:12: Context: This is the overridden method ('property6').
+//   late int property6;
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  late field core::int property4;
+  late field core::int? property5;
+  late covariant-by-declaration field core::int property6;
+  constructor •(core::int property4, core::int? property5, core::int property6) → self::A
+    : self::A::property4 = property4, self::A::property5 = property5, self::A::property6 = property6, super core::Object::•()
+    ;
+}
+abstract class B1 extends core::Object {
+  late final [setter] field core::int property4;
+  late final [setter] field core::int property5;
+  late final [setter] field core::int? property6;
+  constructor •(core::int property4, core::int property5, core::int? property6) → self::B1
+    : self::B1::property4 = property4, self::B1::property5 = property5, self::B1::property6 = property6, super core::Object::•()
+    ;
+}
+abstract class B2 extends core::Object implements self::B1 {
+  synthetic constructor •() → self::B2
+    : super core::Object::•()
+    ;
+  abstract set property4(core::int i) → void;
+  abstract set property5(core::int? i) → void;
+  abstract set property6(core::int i) → void;
+}
+abstract class C1 extends core::Object {
+  late field core::int property4;
+  late field core::int property5;
+  late field core::int property6;
+  constructor •(core::int property4, core::int property5, core::int property6) → self::C1
+    : self::C1::property4 = property4, self::C1::property5 = property5, self::C1::property6 = property6, super core::Object::•()
+    ;
+}
+abstract class C2 extends core::Object implements self::C1 {
+  synthetic constructor •() → self::C2
+    : super core::Object::•()
+    ;
+  abstract get property4() → core::int;
+  abstract get property5() → core::int;
+  abstract get property6() → core::int?;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart.weak.modular.expect
new file mode 100644
index 0000000..1f17578
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart.weak.modular.expect
@@ -0,0 +1,284 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:21:12: Error: The type 'int?' of the getter 'A.property3' is not a subtype of the type 'int' of the setter 'A.property3'.
+//   int? get property3; // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:22:12: Context: This is the declaration of the setter 'A.property3'.
+//   void set property3(int i);
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:38:19: Error: The type 'int?' of the getter 'A.property9' is not a subtype of the type 'int' of the setter 'A.property9'.
+//   static int? get property9 => 0; // error
+//                   ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:39:19: Context: This is the declaration of the setter 'A.property9'.
+//   static void set property9(int value) {}
+//                   ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:63:12: Error: The type 'int?' of the inherited getter 'B1.property3' is not a subtype of the type 'int' of the setter 'B2.property3'.
+//   void set property3(int i); // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:47:12: Context: This is the declaration of the getter 'B1.property3'.
+//   int? get property3;
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:69:12: Error: The type 'int?' of the inherited field 'B1.property6' is not a subtype of the type 'int' of the setter 'B2.property6'.
+//   void set property6(int i); // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:53:14: Context: This is the declaration of the field 'B1.property6'.
+//   final int? property6;
+//              ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:93:12: Error: The type 'int?' of the getter 'C2.property3' is not a subtype of the type 'int' of the inherited setter 'C1.property3'.
+//   int? get property3; // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:77:12: Context: This is the declaration of the setter 'C1.property3'.
+//   void set property3(int i);
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:101:12: Error: The type 'int?' of the getter 'C2.property6' is not a subtype of the type 'int' of the inherited setter 'C1.property6'.
+//   int? get property6; // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:83:7: Context: This is the declaration of the setter 'C1.property6'.
+//   int property6;
+//       ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:101:12: Error: The return type of the method 'C2.property6' is 'int?', which does not match the return type, 'int', of the overridden method, 'C1.property6'.
+// Change to a subtype of 'int'.
+//   int? get property6; // error
+//            ^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:83:7: Context: This is the overridden method ('property6').
+//   int property6;
+//       ^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:120:16: Error: The type 'int?' of the inherited getter 'D1.property3' is not a subtype of the type 'int' of the inherited setter 'D2.property3'.
+// abstract class D3 implements D1, D2 /* error on property3 */ {}
+//                ^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:109:12: Context: This is the declaration of the getter 'D1.property3'.
+//   int? get property3;
+//            ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:117:12: Context: This is the declaration of the setter 'D2.property3'.
+//   void set property3(int i);
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:122:16: Error: The type 'int?' of the inherited getter 'D1.property3' is not a subtype of the type 'int' of the inherited setter 'D2.property3'.
+// abstract class D4 implements D3 /* no need for error on property3 */ {}
+//                ^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:109:12: Context: This is the declaration of the getter 'D1.property3'.
+//   int? get property3;
+//            ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:117:12: Context: This is the declaration of the setter 'D2.property3'.
+//   void set property3(int i);
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:11:10: Error: The type 'int?' of the getter 'property3' is not a subtype of the type 'int' of the setter 'property3'.
+// int? get property3 => 0; // error
+//          ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:12:10: Context: This is the declaration of the setter 'property3'.
+// void set property3(int value) {}
+//          ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:131:12: Error: The type 'int?' of the getter 'property3' is not a subtype of the type 'int' of the setter 'property3'.
+//   int? get property3 => 0; // error
+//            ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:132:12: Context: This is the declaration of the setter 'property3'.
+//   void set property3(int i) {}
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:143:10: Error: The type 'T?' of the getter 'property6' is not a subtype of the type 'T' of the setter 'property6'.
+//   T? get property6 => 0; // error
+//          ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:144:12: Context: This is the declaration of the setter 'property6'.
+//   void set property6(T i) {}
+//            ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:152:19: Error: The type 'int?' of the getter 'property9' is not a subtype of the type 'int' of the setter 'property9'.
+//   static int? get property9 => 0; // error
+//                   ^^^^^^^^^
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:153:19: Context: This is the declaration of the setter 'property9'.
+//   static void set property9(int value) {}
+//                   ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:134:23: Error: A value of type 'int' can't be returned from a function with return type 'T'.
+//   T get property4a => 0; // ok
+//                       ^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:137:24: Error: A value of type 'int' can't be returned from a function with return type 'T?'.
+//   T? get property4b => 0; // ok
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:140:22: Error: A value of type 'int' can't be returned from a function with return type 'T'.
+//   T get property5 => 0; // ok
+//                      ^
+//
+// pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:143:23: Error: A value of type 'int' can't be returned from a function with return type 'T?'.
+//   T? get property6 => 0; // error
+//                       ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  field core::int property4;
+  field core::int? property5;
+  covariant-by-declaration field core::int property6;
+  constructor •(core::int property4, core::int? property5, core::int property6) → self::A
+    : self::A::property4 = property4, self::A::property5 = property5, self::A::property6 = property6, super core::Object::•()
+    ;
+  abstract get property1() → core::int;
+  abstract set property1(core::int i) → void;
+  abstract get property2() → core::int;
+  abstract set property2(core::int? i) → void;
+  abstract get property3() → core::int?;
+  abstract set property3(core::int i) → void;
+  static get property7() → core::int
+    return 0;
+  static set property7(core::int value) → void {}
+  static get property8() → core::int
+    return 0;
+  static set property8(core::int? value) → void {}
+  static get property9() → core::int?
+    return 0;
+  static set property9(core::int value) → void {}
+}
+abstract class B1 extends core::Object {
+  final field core::int property4;
+  final field core::int property5;
+  final field core::int? property6;
+  constructor •(core::int property4, core::int property5, core::int? property6) → self::B1
+    : self::B1::property4 = property4, self::B1::property5 = property5, self::B1::property6 = property6, super core::Object::•()
+    ;
+  abstract get property1() → core::int;
+  abstract get property2() → core::int;
+  abstract get property3() → core::int?;
+}
+abstract class B2 extends core::Object implements self::B1 {
+  synthetic constructor •() → self::B2
+    : super core::Object::•()
+    ;
+  abstract set property1(core::int i) → void;
+  abstract set property2(core::int? i) → void;
+  abstract set property3(core::int i) → void;
+  abstract set property4(core::int i) → void;
+  abstract set property5(core::int? i) → void;
+  abstract set property6(core::int i) → void;
+}
+abstract class C1 extends core::Object {
+  field core::int property4;
+  field core::int? property5;
+  field core::int property6;
+  constructor •(core::int property4, core::int? property5, core::int property6) → self::C1
+    : self::C1::property4 = property4, self::C1::property5 = property5, self::C1::property6 = property6, super core::Object::•()
+    ;
+  abstract set property1(core::int i) → void;
+  abstract set property2(core::int? i) → void;
+  abstract set property3(core::int i) → void;
+}
+abstract class C2 extends core::Object implements self::C1 {
+  synthetic constructor •() → self::C2
+    : super core::Object::•()
+    ;
+  abstract get property1() → core::int;
+  abstract get property2() → core::int;
+  abstract get property3() → core::int?;
+  abstract get property4() → core::int;
+  abstract get property5() → core::int;
+  abstract get property6() → core::int?;
+}
+abstract class D1 extends core::Object {
+  synthetic constructor •() → self::D1
+    : super core::Object::•()
+    ;
+  abstract get property1() → core::int;
+  abstract get property2() → core::int;
+  abstract get property3() → core::int?;
+}
+abstract class D2 extends core::Object {
+  synthetic constructor •() → self::D2
+    : super core::Object::•()
+    ;
+  abstract set property1(core::int i) → void;
+  abstract set property2(core::int? i) → void;
+  abstract set property3(core::int i) → void;
+}
+abstract class D3 extends core::Object implements self::D1, self::D2 {
+  synthetic constructor •() → self::D3
+    : super core::Object::•()
+    ;
+}
+abstract class D4 extends core::Object implements self::D3 {
+  synthetic constructor •() → self::D4
+    : super core::Object::•()
+    ;
+}
+extension Extension<T extends core::num> on core::int {
+  get property1 = self::Extension|get#property1;
+  get property2 = self::Extension|get#property2;
+  get property3 = self::Extension|get#property3;
+  get property4a = self::Extension|get#property4a;
+  get property4b = self::Extension|get#property4b;
+  get property5 = self::Extension|get#property5;
+  get property6 = self::Extension|get#property6;
+  static get property7 = get self::Extension|property7;
+  static get property8 = get self::Extension|property8;
+  static get property9 = get self::Extension|property9;
+  set property1 = self::Extension|set#property1;
+  set property2 = self::Extension|set#property2;
+  set property3 = self::Extension|set#property3;
+  set property4a = self::Extension|set#property4a;
+  set property4b = self::Extension|set#property4b;
+  set property5 = self::Extension|set#property5;
+  set property6 = self::Extension|set#property6;
+  static set property7 = set self::Extension|property7;
+  static set property8 = set self::Extension|property8;
+  static set property9 = set self::Extension|property9;
+}
+static get property1() → core::int
+  return 0;
+static set property1(core::int value) → void {}
+static get property2() → core::int
+  return 0;
+static set property2(core::int? value) → void {}
+static get property3() → core::int?
+  return 0;
+static set property3(core::int value) → void {}
+static method Extension|get#property1<T extends core::num>(lowered final core::int #this) → core::int
+  return 0;
+static method Extension|set#property1<T extends core::num>(lowered final core::int #this, core::int i) → void {}
+static method Extension|get#property2<T extends core::num>(lowered final core::int #this) → core::int
+  return 0;
+static method Extension|set#property2<T extends core::num>(lowered final core::int #this, core::int? i) → void {}
+static method Extension|get#property3<T extends core::num>(lowered final core::int #this) → core::int?
+  return 0;
+static method Extension|set#property3<T extends core::num>(lowered final core::int #this, core::int i) → void {}
+static method Extension|get#property4a<T extends core::num>(lowered final core::int #this) → self::Extension|get#property4a::T
+  return invalid-expression "pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:134:23: Error: A value of type 'int' can't be returned from a function with return type 'T'.
+  T get property4a => 0; // ok
+                      ^" in 0 as{TypeError,ForNonNullableByDefault} Never;
+static method Extension|set#property4a<T extends core::num>(lowered final core::int #this, self::Extension|set#property4a::T i) → void {}
+static method Extension|get#property4b<T extends core::num>(lowered final core::int #this) → self::Extension|get#property4b::T?
+  return invalid-expression "pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:137:24: Error: A value of type 'int' can't be returned from a function with return type 'T?'.
+  T? get property4b => 0; // ok
+                       ^" in 0 as{TypeError,ForNonNullableByDefault} Never;
+static method Extension|set#property4b<T extends core::num>(lowered final core::int #this, self::Extension|set#property4b::T? i) → void {}
+static method Extension|get#property5<T extends core::num>(lowered final core::int #this) → self::Extension|get#property5::T
+  return invalid-expression "pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:140:22: Error: A value of type 'int' can't be returned from a function with return type 'T'.
+  T get property5 => 0; // ok
+                     ^" in 0 as{TypeError,ForNonNullableByDefault} Never;
+static method Extension|set#property5<T extends core::num>(lowered final core::int #this, self::Extension|set#property5::T? i) → void {}
+static method Extension|get#property6<T extends core::num>(lowered final core::int #this) → self::Extension|get#property6::T?
+  return invalid-expression "pkg/front_end/testcases/nnbd/getter_vs_setter_type_nnbd.dart:143:23: Error: A value of type 'int' can't be returned from a function with return type 'T?'.
+  T? get property6 => 0; // error
+                      ^" in 0 as{TypeError,ForNonNullableByDefault} Never;
+static method Extension|set#property6<T extends core::num>(lowered final core::int #this, self::Extension|set#property6::T i) → void {}
+static get Extension|property7() → core::int
+  return 0;
+static set Extension|property7(core::int value) → void {}
+static get Extension|property8() → core::int
+  return 0;
+static set Extension|property8(core::int? value) → void {}
+static get Extension|property9() → core::int?
+  return 0;
+static set Extension|property9(core::int value) → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/infer_from_late_variable.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/infer_from_late_variable.dart.weak.modular.expect
new file mode 100644
index 0000000..954dd07
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/infer_from_late_variable.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method f<T extends core::Object? = dynamic>(self::f::T% t) → self::f::T%
+  return t;
+static method main() → dynamic {
+  late core::int local;
+  local = self::f<core::int>(0);
+}
diff --git a/pkg/front_end/testcases/nnbd/infer_from_promoted.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/infer_from_promoted.dart.weak.modular.expect
new file mode 100644
index 0000000..2e2a614
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/infer_from_promoted.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/infer_from_promoted.dart:16:21: Error: A value of type 'String' can't be returned from a function with return type 'int'.
+//   d = (a, b) => '$a';
+//                     ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F<invariant T extends core::Object? = dynamic> = (T%, T%) → T%;
+static method test1() → dynamic {
+  dynamic d = (core::int a, core::int b) → core::int => a;
+  d as{ForNonNullableByDefault} (core::int, core::int) → core::int;
+  d = <S extends core::Object? = dynamic>(S% a, S% b) → S% => a;
+}
+static method test2() → dynamic {
+  dynamic d = (core::int a, core::int b) → core::int => a;
+  d as{ForNonNullableByDefault} (core::int, core::int) → core::int;
+  d = (core::int a, core::int b) → core::int => invalid-expression "pkg/front_end/testcases/nnbd/infer_from_promoted.dart:16:21: Error: A value of type 'String' can't be returned from a function with return type 'int'.
+  d = (a, b) => '\$a';
+                    ^" in "${a}" as{TypeError,ForNonNullableByDefault} core::int;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/infer_if_null.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/infer_if_null.dart.weak.modular.expect
new file mode 100644
index 0000000..fe4267a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/infer_if_null.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A2 extends core::Object {
+  field core::String? foo = null;
+  synthetic constructor •() → self::A2
+    : super core::Object::•()
+    ;
+}
+class A5 extends core::Object {
+  synthetic constructor •() → self::A5
+    : super core::Object::•()
+    ;
+  operator []=(core::int index, core::String? value) → void {}
+  operator [](core::int index) → core::String?
+    return null;
+}
+class B5 extends self::A5 {
+  synthetic constructor •() → self::B5
+    : super self::A5::•()
+    ;
+  method test5() → dynamic {
+    core::String s = let final core::int #t1 = 0 in let final core::String? #t2 = super.{self::A5::[]}(#t1) in #t2 == null ?{core::String} let final core::String #t3 = "bar" in let final void #t4 = super.{self::A5::[]=}(#t1, #t3) in #t3 : #t2{core::String};
+  }
+}
+class A7 extends core::Object {
+  field core::String foo = "foo";
+  field core::String? bar = null;
+  synthetic constructor •() → self::A7
+    : super core::Object::•()
+    ;
+}
+extension E6 on core::double {
+  operator []= = self::E6|[]=;
+  operator [] = self::E6|[];
+}
+static method hest1<T extends core::Object? = dynamic>() → self::hest1::T%
+  return throw "hest";
+static method test1() → dynamic {
+  function foo() → core::String?
+    return null;
+  function bar() → core::String
+    return "bar";
+  core::String s = let final core::String? #t5 = foo(){() → core::String?} in #t5 == null ?{core::String} bar(){() → core::String} : #t5{core::String};
+  core::String s2 = let final core::String? #t6 = self::hest1<core::String?>() in #t6 == null ?{core::String} "fisk" : #t6{core::String};
+}
+static method test2(self::A2 a) → dynamic {
+  core::String s = let final self::A2 #t7 = a in let final core::String? #t8 = #t7.{self::A2::foo}{core::String?} in #t8 == null ?{core::String} #t7.{self::A2::foo} = "bar" : #t8{core::String};
+}
+static method test3() → dynamic {
+  core::String? s = null;
+  core::String s2 = let final core::String? #t9 = s in #t9 == null ?{core::String} s = "bar" : #t9{core::String};
+}
+static method test4() → dynamic {
+  core::List<core::String?> list = <core::String?>[null];
+  core::String s = let final core::List<core::String?> #t10 = list in let final core::int #t11 = 0 in let final core::String? #t12 = #t10.{core::List::[]}(#t11){(core::int) → core::String?} in #t12 == null ?{core::String} let final core::String #t13 = "bar" in let final void #t14 = #t10.{core::List::[]=}(#t11, #t13){(core::int, core::String?) → void} in #t13 : #t12{core::String};
+}
+static method E6|[]=(lowered final core::double #this, core::int index, core::String? value) → void {}
+static method E6|[](lowered final core::double #this, core::int index) → core::String?
+  return null;
+static method test6() → dynamic {
+  core::String s = let final core::double #t15 = 3.14 in let final core::int #t16 = 0 in let final core::String? #t17 = self::E6|[](#t15, #t16) in #t17 == null ?{core::String} let final core::String #t18 = "bar" in let final void #t19 = self::E6|[]=(#t15, #t16, #t18) in #t18 : #t17{core::String};
+}
+static method test7(self::A7? a) → dynamic {
+  core::String? s = let final self::A7? #t20 = a in #t20 == null ?{core::String?} null : let final core::String #t21 = #t20.{self::A7::foo}{core::String} in #t21 == null ?{core::String} #t20.{self::A7::foo} = "bar" : #t21;
+  core::String? s2 = let final self::A7? #t22 = a in #t22 == null ?{core::String?} null : let final core::String? #t23 = #t22.{self::A7::bar}{core::String?} in #t23 == null ?{core::String} #t22.{self::A7::bar} = "bar" : #t23{core::String};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/infer_method_types.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/infer_method_types.dart.weak.modular.expect
new file mode 100644
index 0000000..d29fed9
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/infer_method_types.dart.weak.modular.expect
@@ -0,0 +1,77 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  abstract method m(covariant-by-declaration core::int a) → core::Object?;
+}
+abstract class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+  abstract method m(covariant-by-declaration core::num a) → dynamic;
+}
+abstract class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  abstract method m(core::num a) → void;
+}
+abstract class D extends core::Object implements self::A {
+  synthetic constructor •() → self::D
+    : super core::Object::•()
+    ;
+  abstract method m(covariant-by-declaration core::int a) → core::Object?;
+}
+abstract class E extends core::Object implements self::B {
+  synthetic constructor •() → self::E
+    : super core::Object::•()
+    ;
+  abstract method m(covariant-by-declaration core::num a) → dynamic;
+}
+abstract class F extends core::Object {
+  synthetic constructor •() → self::F
+    : super core::Object::•()
+    ;
+  abstract method m(core::int a) → core::Object?;
+}
+abstract class G extends core::Object implements self::C {
+  synthetic constructor •() → self::G
+    : super core::Object::•()
+    ;
+  abstract method m(core::num a) → void;
+}
+abstract class H extends core::Object implements self::D, self::E, self::F, self::C {
+  synthetic constructor •() → self::H
+    : super core::Object::•()
+    ;
+  abstract member-signature method m(covariant-by-declaration core::num a) → core::Object?; -> self::E::m
+}
+abstract class I extends core::Object implements self::D {
+  synthetic constructor •() → self::I
+    : super core::Object::•()
+    ;
+  abstract method m(covariant-by-declaration core::int a) → core::Object?;
+}
+abstract class J extends core::Object implements self::H {
+  synthetic constructor •() → self::J
+    : super core::Object::•()
+    ;
+  abstract method m(covariant-by-declaration core::num a) → core::Object?;
+}
+abstract class K extends core::Object implements self::I, self::E, self::G {
+  synthetic constructor •() → self::K
+    : super core::Object::•()
+    ;
+  abstract member-signature method m(covariant-by-declaration core::num a) → core::Object?; -> self::E::m
+}
+abstract class L extends core::Object implements self::K {
+  synthetic constructor •() → self::L
+    : super core::Object::•()
+    ;
+  abstract method m(covariant-by-declaration core::num a) → core::Object?;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/infer_object_from_dynamic.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/infer_object_from_dynamic.dart.weak.modular.expect
new file mode 100644
index 0000000..4c6feac
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/infer_object_from_dynamic.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/infer_object_from_dynamic.dart:20:5: Error: This expression has type 'void' and can't be used.
+//   g(v);
+//     ^
+//
+// pkg/front_end/testcases/nnbd/infer_object_from_dynamic.dart:27:5: Error: This expression has type 'void' and can't be used.
+//   h(v);
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method f<T extends core::Object? = dynamic>(self::f::T% t) → self::f::T%
+  return t;
+static method g<T extends core::Object? = dynamic>(self::g::T? t) → self::g::T%
+  return t!;
+static method h<T extends core::Object>(self::h::T? t) → self::h::T
+  return t!;
+static method foo(dynamic d, void v, core::Object? onull, core::Object o, core::String? snull, core::String s) → dynamic {
+  self::f<dynamic>(d);
+  self::f<void>(v);
+  self::f<core::Object?>(onull);
+  self::f<core::Object>(o);
+  self::f<core::String?>(snull);
+  self::f<core::String>(s);
+  self::g<core::Object>(d);
+  self::g<core::Object>(invalid-expression "pkg/front_end/testcases/nnbd/infer_object_from_dynamic.dart:20:5: Error: This expression has type 'void' and can't be used.
+  g(v);
+    ^" in v);
+  self::g<core::Object>(onull);
+  self::g<core::Object>(o);
+  self::g<core::String>(snull);
+  self::g<core::String>(s);
+  self::h<core::Object>(d);
+  self::h<core::Object>(invalid-expression "pkg/front_end/testcases/nnbd/infer_object_from_dynamic.dart:27:5: Error: This expression has type 'void' and can't be used.
+  h(v);
+    ^" in v);
+  self::h<core::Object>(onull);
+  self::h<core::Object>(o);
+  self::h<core::String>(snull);
+  self::h<core::String>(s);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/injected_late_field_checks/main.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/injected_late_field_checks/main.dart.weak.modular.expect
new file mode 100644
index 0000000..75d67bf
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/injected_late_field_checks/main.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+
+import "dart:test";
+
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as self2;
+import "dart:_internal" as _in;
+import "dart:core" as core;
+
+import "dart:_internal";
+
+@#C1
+class Class extends core::Object {
+  late field core::int foo /* from org-dartlang-testcase:///patch_lib.dart */;
+  constructor bar() → self2::Class
+    : super core::Object::•()
+    ;
+  constructor baz(core::int foo) → self2::Class
+    : self2::Class::foo = foo, super core::Object::•()
+    ;
+}
+
+constants  {
+  #C1 = _in::_Patch {}
+}
diff --git a/pkg/front_end/testcases/nnbd/instance_duplicates.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/instance_duplicates.dart.weak.modular.expect
new file mode 100644
index 0000000..7e8a8f2
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/instance_duplicates.dart.weak.modular.expect
@@ -0,0 +1,668 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:7:8: Error: 'methodAndField1' is already declared in this scope.
+//   int? methodAndField1;
+//        ^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:6:8: Context: Previous declaration of 'methodAndField1'.
+//   int? methodAndField1() {}
+//        ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:10:8: Error: 'methodAndField2' is already declared in this scope.
+//   int? methodAndField2() {}
+//        ^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:9:8: Context: Previous declaration of 'methodAndField2'.
+//   int? methodAndField2;
+//        ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:13:14: Error: 'methodAndFinalField1' is already declared in this scope.
+//   final int? methodAndFinalField1 = 0;
+//              ^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:12:8: Context: Previous declaration of 'methodAndFinalField1'.
+//   int? methodAndFinalField1() {}
+//        ^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:16:8: Error: 'methodAndFinalField2' is already declared in this scope.
+//   int? methodAndFinalField2() {}
+//        ^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:15:14: Context: Previous declaration of 'methodAndFinalField2'.
+//   final int? methodAndFinalField2 = 0;
+//              ^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:19:8: Error: 'methodAndFieldAndSetter1' is already declared in this scope.
+//   int? methodAndFieldAndSetter1;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:18:8: Context: Previous declaration of 'methodAndFieldAndSetter1'.
+//   int? methodAndFieldAndSetter1() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:23:8: Error: 'methodAndFieldAndSetter2' is already declared in this scope.
+//   int? methodAndFieldAndSetter2() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:22:8: Context: Previous declaration of 'methodAndFieldAndSetter2'.
+//   int? methodAndFieldAndSetter2;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:28:8: Error: 'methodAndFieldAndSetter3' is already declared in this scope.
+//   int? methodAndFieldAndSetter3;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:27:8: Context: Previous declaration of 'methodAndFieldAndSetter3'.
+//   int? methodAndFieldAndSetter3() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:32:8: Error: 'methodAndFieldAndSetter4' is already declared in this scope.
+//   int? methodAndFieldAndSetter4() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:31:8: Context: Previous declaration of 'methodAndFieldAndSetter4'.
+//   int? methodAndFieldAndSetter4;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:35:14: Error: 'methodAndFinalFieldAndSetter1' is already declared in this scope.
+//   final int? methodAndFinalFieldAndSetter1 = 0;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:34:8: Context: Previous declaration of 'methodAndFinalFieldAndSetter1'.
+//   int? methodAndFinalFieldAndSetter1() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:39:8: Error: 'methodAndFinalFieldAndSetter2' is already declared in this scope.
+//   int? methodAndFinalFieldAndSetter2() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:38:14: Context: Previous declaration of 'methodAndFinalFieldAndSetter2'.
+//   final int? methodAndFinalFieldAndSetter2 = 0;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:44:14: Error: 'methodAndFinalFieldAndSetter3' is already declared in this scope.
+//   final int? methodAndFinalFieldAndSetter3 = 0;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:43:8: Context: Previous declaration of 'methodAndFinalFieldAndSetter3'.
+//   int? methodAndFinalFieldAndSetter3() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:48:8: Error: 'methodAndFinalFieldAndSetter4' is already declared in this scope.
+//   int? methodAndFinalFieldAndSetter4() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:47:14: Context: Previous declaration of 'methodAndFinalFieldAndSetter4'.
+//   final int? methodAndFinalFieldAndSetter4 = 0;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:54:3: Error: The return type of the setter must be 'void' or absent.
+// Try removing the return type, or define a method rather than a setter.
+//   int? set methodAndSetter2() {}
+//   ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:63:14: Error: 'fieldAndFinalFieldAndSetter1' is already declared in this scope.
+//   final int? fieldAndFinalFieldAndSetter1 = 0;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:62:8: Context: Previous declaration of 'fieldAndFinalFieldAndSetter1'.
+//   int? fieldAndFinalFieldAndSetter1;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:67:8: Error: 'fieldAndFinalFieldAndSetter2' is already declared in this scope.
+//   int? fieldAndFinalFieldAndSetter2;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:66:14: Context: Previous declaration of 'fieldAndFinalFieldAndSetter2'.
+//   final int? fieldAndFinalFieldAndSetter2 = 0;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:72:14: Error: 'fieldAndFinalFieldAndSetter3' is already declared in this scope.
+//   final int? fieldAndFinalFieldAndSetter3 = 0;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:71:8: Context: Previous declaration of 'fieldAndFinalFieldAndSetter3'.
+//   int? fieldAndFinalFieldAndSetter3;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:76:8: Error: 'fieldAndFinalFieldAndSetter4' is already declared in this scope.
+//   int? fieldAndFinalFieldAndSetter4;
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:75:14: Context: Previous declaration of 'fieldAndFinalFieldAndSetter4'.
+//   final int? fieldAndFinalFieldAndSetter4 = 0;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:20:12: Error: Conflicts with the implicit setter of the field 'methodAndFieldAndSetter1'.
+//   void set methodAndFieldAndSetter1(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:19:8: Error: Conflicts with setter 'methodAndFieldAndSetter1'.
+//   int? methodAndFieldAndSetter1;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:24:12: Error: Conflicts with the implicit setter of the field 'methodAndFieldAndSetter2'.
+//   void set methodAndFieldAndSetter2(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:22:8: Error: Conflicts with setter 'methodAndFieldAndSetter2'.
+//   int? methodAndFieldAndSetter2;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:26:12: Error: Conflicts with the implicit setter of the field 'methodAndFieldAndSetter3'.
+//   void set methodAndFieldAndSetter3(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:28:8: Error: Conflicts with setter 'methodAndFieldAndSetter3'.
+//   int? methodAndFieldAndSetter3;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:30:12: Error: Conflicts with the implicit setter of the field 'methodAndFieldAndSetter4'.
+//   void set methodAndFieldAndSetter4(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:31:8: Error: Conflicts with setter 'methodAndFieldAndSetter4'.
+//   int? methodAndFieldAndSetter4;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:57:12: Error: Conflicts with the implicit setter of the field 'fieldAndSetter1'.
+//   void set fieldAndSetter1(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:56:8: Error: Conflicts with setter 'fieldAndSetter1'.
+//   int? fieldAndSetter1;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:60:12: Error: Conflicts with the implicit setter of the field 'fieldAndSetter2'.
+//   void set fieldAndSetter2(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:59:8: Error: Conflicts with setter 'fieldAndSetter2'.
+//   int? fieldAndSetter2;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:64:12: Error: Conflicts with the implicit setter of the field 'fieldAndFinalFieldAndSetter1'.
+//   void set fieldAndFinalFieldAndSetter1(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:62:8: Error: Conflicts with setter 'fieldAndFinalFieldAndSetter1'.
+//   int? fieldAndFinalFieldAndSetter1;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:68:12: Error: Conflicts with the implicit setter of the field 'fieldAndFinalFieldAndSetter2'.
+//   void set fieldAndFinalFieldAndSetter2(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:67:8: Error: Conflicts with setter 'fieldAndFinalFieldAndSetter2'.
+//   int? fieldAndFinalFieldAndSetter2;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:70:12: Error: Conflicts with the implicit setter of the field 'fieldAndFinalFieldAndSetter3'.
+//   void set fieldAndFinalFieldAndSetter3(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:71:8: Error: Conflicts with setter 'fieldAndFinalFieldAndSetter3'.
+//   int? fieldAndFinalFieldAndSetter3;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:74:12: Error: Conflicts with the implicit setter of the field 'fieldAndFinalFieldAndSetter4'.
+//   void set fieldAndFinalFieldAndSetter4(int? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:76:8: Error: Conflicts with setter 'fieldAndFinalFieldAndSetter4'.
+//   int? fieldAndFinalFieldAndSetter4;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:40:12: Error: 'methodAndFinalFieldAndSetter2' is already declared in this scope.
+//   void set methodAndFinalFieldAndSetter2(int? value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:39:8: Context: Previous declaration of 'methodAndFinalFieldAndSetter2'.
+//   int? methodAndFinalFieldAndSetter2() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:51:12: Error: 'methodAndSetter1' is already declared in this scope.
+//   void set methodAndSetter1(int? value) {}
+//            ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:50:8: Context: Previous declaration of 'methodAndSetter1'.
+//   int? methodAndSetter1() {}
+//        ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:54:12: Error: 'methodAndSetter2' is already declared in this scope.
+//   int? set methodAndSetter2() {}
+//            ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:53:8: Context: Previous declaration of 'methodAndSetter2'.
+//   void methodAndSetter2(int? value) {}
+//        ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:54:28: Error: A setter should have exactly one formal parameter.
+//   int? set methodAndSetter2() {}
+//                            ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:80:5: Error: Can't use 'methodAndField1' because it is declared more than once.
+//   c.methodAndField1 = c.methodAndField1;
+//     ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:80:25: Error: Can't use 'methodAndField1' because it is declared more than once.
+//   c.methodAndField1 = c.methodAndField1;
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:80:25: Error: The getter 'methodAndField1' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndField1'.
+//   c.methodAndField1 = c.methodAndField1;
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:80:5: Error: The setter 'methodAndField1' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'methodAndField1'.
+//   c.methodAndField1 = c.methodAndField1;
+//     ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:81:5: Error: Can't use 'methodAndField2' because it is declared more than once.
+//   c.methodAndField2 = c.methodAndField2;
+//     ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:81:25: Error: Can't use 'methodAndField2' because it is declared more than once.
+//   c.methodAndField2 = c.methodAndField2;
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:81:25: Error: The getter 'methodAndField2' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndField2'.
+//   c.methodAndField2 = c.methodAndField2;
+//                         ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:81:5: Error: The setter 'methodAndField2' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'methodAndField2'.
+//   c.methodAndField2 = c.methodAndField2;
+//     ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:82:5: Error: Can't use 'methodAndFinalField1' because it is declared more than once.
+//   c.methodAndFinalField1;
+//     ^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:82:5: Error: The getter 'methodAndFinalField1' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFinalField1'.
+//   c.methodAndFinalField1;
+//     ^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:83:5: Error: Can't use 'methodAndFinalField2' because it is declared more than once.
+//   c.methodAndFinalField2;
+//     ^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:83:5: Error: The getter 'methodAndFinalField2' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFinalField2'.
+//   c.methodAndFinalField2;
+//     ^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:84:5: Error: Can't use 'methodAndFieldAndSetter1' because it is declared more than once.
+//   c.methodAndFieldAndSetter1 = c.methodAndFieldAndSetter1;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:84:34: Error: Can't use 'methodAndFieldAndSetter1' because it is declared more than once.
+//   c.methodAndFieldAndSetter1 = c.methodAndFieldAndSetter1;
+//                                  ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:84:34: Error: The getter 'methodAndFieldAndSetter1' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFieldAndSetter1'.
+//   c.methodAndFieldAndSetter1 = c.methodAndFieldAndSetter1;
+//                                  ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:84:5: Error: The setter 'methodAndFieldAndSetter1' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'methodAndFieldAndSetter1'.
+//   c.methodAndFieldAndSetter1 = c.methodAndFieldAndSetter1;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:85:5: Error: Can't use 'methodAndFieldAndSetter2' because it is declared more than once.
+//   c.methodAndFieldAndSetter2 = c.methodAndFieldAndSetter2;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:85:34: Error: Can't use 'methodAndFieldAndSetter2' because it is declared more than once.
+//   c.methodAndFieldAndSetter2 = c.methodAndFieldAndSetter2;
+//                                  ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:85:34: Error: The getter 'methodAndFieldAndSetter2' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFieldAndSetter2'.
+//   c.methodAndFieldAndSetter2 = c.methodAndFieldAndSetter2;
+//                                  ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:85:5: Error: The setter 'methodAndFieldAndSetter2' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'methodAndFieldAndSetter2'.
+//   c.methodAndFieldAndSetter2 = c.methodAndFieldAndSetter2;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:86:5: Error: Can't use 'methodAndFieldAndSetter3' because it is declared more than once.
+//   c.methodAndFieldAndSetter3 = c.methodAndFieldAndSetter3;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:86:34: Error: Can't use 'methodAndFieldAndSetter3' because it is declared more than once.
+//   c.methodAndFieldAndSetter3 = c.methodAndFieldAndSetter3;
+//                                  ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:86:34: Error: The getter 'methodAndFieldAndSetter3' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFieldAndSetter3'.
+//   c.methodAndFieldAndSetter3 = c.methodAndFieldAndSetter3;
+//                                  ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:86:5: Error: The setter 'methodAndFieldAndSetter3' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'methodAndFieldAndSetter3'.
+//   c.methodAndFieldAndSetter3 = c.methodAndFieldAndSetter3;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:87:5: Error: Can't use 'methodAndFieldAndSetter4' because it is declared more than once.
+//   c.methodAndFieldAndSetter4 = c.methodAndFieldAndSetter4;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:87:34: Error: Can't use 'methodAndFieldAndSetter4' because it is declared more than once.
+//   c.methodAndFieldAndSetter4 = c.methodAndFieldAndSetter4;
+//                                  ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:87:34: Error: The getter 'methodAndFieldAndSetter4' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFieldAndSetter4'.
+//   c.methodAndFieldAndSetter4 = c.methodAndFieldAndSetter4;
+//                                  ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:87:5: Error: The setter 'methodAndFieldAndSetter4' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'methodAndFieldAndSetter4'.
+//   c.methodAndFieldAndSetter4 = c.methodAndFieldAndSetter4;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:88:39: Error: Can't use 'methodAndFinalFieldAndSetter1' because it is declared more than once.
+//   c.methodAndFinalFieldAndSetter1 = c.methodAndFinalFieldAndSetter1;
+//                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:88:39: Error: The getter 'methodAndFinalFieldAndSetter1' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFinalFieldAndSetter1'.
+//   c.methodAndFinalFieldAndSetter1 = c.methodAndFinalFieldAndSetter1;
+//                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:89:39: Error: Can't use 'methodAndFinalFieldAndSetter2' because it is declared more than once.
+//   c.methodAndFinalFieldAndSetter2 = c.methodAndFinalFieldAndSetter2;
+//                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:89:39: Error: The getter 'methodAndFinalFieldAndSetter2' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFinalFieldAndSetter2'.
+//   c.methodAndFinalFieldAndSetter2 = c.methodAndFinalFieldAndSetter2;
+//                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:90:39: Error: Can't use 'methodAndFinalFieldAndSetter3' because it is declared more than once.
+//   c.methodAndFinalFieldAndSetter3 = c.methodAndFinalFieldAndSetter3;
+//                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:90:39: Error: The getter 'methodAndFinalFieldAndSetter3' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFinalFieldAndSetter3'.
+//   c.methodAndFinalFieldAndSetter3 = c.methodAndFinalFieldAndSetter3;
+//                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:91:39: Error: Can't use 'methodAndFinalFieldAndSetter4' because it is declared more than once.
+//   c.methodAndFinalFieldAndSetter4 = c.methodAndFinalFieldAndSetter4;
+//                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:91:39: Error: The getter 'methodAndFinalFieldAndSetter4' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFinalFieldAndSetter4'.
+//   c.methodAndFinalFieldAndSetter4 = c.methodAndFinalFieldAndSetter4;
+//                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:92:26: Error: A value of type 'int? Function()' can't be assigned to a variable of type 'int?'.
+//   c.methodAndSetter1 = c.methodAndSetter1;
+//                          ^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:96:5: Error: Can't use 'fieldAndFinalFieldAndSetter1' because it is declared more than once.
+//   c.fieldAndFinalFieldAndSetter1 = c.fieldAndFinalFieldAndSetter1;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:96:38: Error: Can't use 'fieldAndFinalFieldAndSetter1' because it is declared more than once.
+//   c.fieldAndFinalFieldAndSetter1 = c.fieldAndFinalFieldAndSetter1;
+//                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:96:38: Error: The getter 'fieldAndFinalFieldAndSetter1' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'fieldAndFinalFieldAndSetter1'.
+//   c.fieldAndFinalFieldAndSetter1 = c.fieldAndFinalFieldAndSetter1;
+//                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:96:5: Error: The setter 'fieldAndFinalFieldAndSetter1' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'fieldAndFinalFieldAndSetter1'.
+//   c.fieldAndFinalFieldAndSetter1 = c.fieldAndFinalFieldAndSetter1;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:97:5: Error: Can't use 'fieldAndFinalFieldAndSetter2' because it is declared more than once.
+//   c.fieldAndFinalFieldAndSetter2 = c.fieldAndFinalFieldAndSetter2;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:97:38: Error: Can't use 'fieldAndFinalFieldAndSetter2' because it is declared more than once.
+//   c.fieldAndFinalFieldAndSetter2 = c.fieldAndFinalFieldAndSetter2;
+//                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:97:38: Error: The getter 'fieldAndFinalFieldAndSetter2' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'fieldAndFinalFieldAndSetter2'.
+//   c.fieldAndFinalFieldAndSetter2 = c.fieldAndFinalFieldAndSetter2;
+//                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:97:5: Error: The setter 'fieldAndFinalFieldAndSetter2' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'fieldAndFinalFieldAndSetter2'.
+//   c.fieldAndFinalFieldAndSetter2 = c.fieldAndFinalFieldAndSetter2;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:98:5: Error: Can't use 'fieldAndFinalFieldAndSetter3' because it is declared more than once.
+//   c.fieldAndFinalFieldAndSetter3 = c.fieldAndFinalFieldAndSetter3;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:98:38: Error: Can't use 'fieldAndFinalFieldAndSetter3' because it is declared more than once.
+//   c.fieldAndFinalFieldAndSetter3 = c.fieldAndFinalFieldAndSetter3;
+//                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:98:38: Error: The getter 'fieldAndFinalFieldAndSetter3' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'fieldAndFinalFieldAndSetter3'.
+//   c.fieldAndFinalFieldAndSetter3 = c.fieldAndFinalFieldAndSetter3;
+//                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:98:5: Error: The setter 'fieldAndFinalFieldAndSetter3' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'fieldAndFinalFieldAndSetter3'.
+//   c.fieldAndFinalFieldAndSetter3 = c.fieldAndFinalFieldAndSetter3;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:99:5: Error: Can't use 'fieldAndFinalFieldAndSetter4' because it is declared more than once.
+//   c.fieldAndFinalFieldAndSetter4 = c.fieldAndFinalFieldAndSetter4;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:99:38: Error: Can't use 'fieldAndFinalFieldAndSetter4' because it is declared more than once.
+//   c.fieldAndFinalFieldAndSetter4 = c.fieldAndFinalFieldAndSetter4;
+//                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:99:38: Error: The getter 'fieldAndFinalFieldAndSetter4' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'fieldAndFinalFieldAndSetter4'.
+//   c.fieldAndFinalFieldAndSetter4 = c.fieldAndFinalFieldAndSetter4;
+//                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:99:5: Error: The setter 'fieldAndFinalFieldAndSetter4' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'fieldAndFinalFieldAndSetter4'.
+//   c.fieldAndFinalFieldAndSetter4 = c.fieldAndFinalFieldAndSetter4;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:66:14: Error: Final field 'fieldAndFinalFieldAndSetter2' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int? fieldAndFinalFieldAndSetter2 = 0;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/instance_duplicates.dart:75:14: Error: Final field 'fieldAndFinalFieldAndSetter4' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int? fieldAndFinalFieldAndSetter4 = 0;
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int? methodAndField2 = null;
+  final field core::int? methodAndFinalField2 = null;
+  field core::int? methodAndFieldAndSetter2 = null;
+  field core::int? methodAndFieldAndSetter4 = null;
+  final field core::int? methodAndFinalFieldAndSetter2 = null;
+  final field core::int? methodAndFinalFieldAndSetter4 = null;
+  field core::int? fieldAndSetter1 = null;
+  field core::int? fieldAndSetter2 = null;
+  field core::int? fieldAndFinalFieldAndSetter1 = null;
+  final field core::int? fieldAndFinalFieldAndSetter2 = null;
+  field core::int? fieldAndFinalFieldAndSetter3 = null;
+  final field core::int? fieldAndFinalFieldAndSetter4 = null;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  method methodAndField1() → core::int? {}
+  method methodAndFinalField1() → core::int? {}
+  method methodAndFieldAndSetter1() → core::int? {}
+  method methodAndFieldAndSetter3() → core::int? {}
+  method methodAndFinalFieldAndSetter1() → core::int? {}
+  set methodAndFinalFieldAndSetter1(core::int? value) → void {}
+  set methodAndFinalFieldAndSetter2(core::int? value) → void {}
+  set methodAndFinalFieldAndSetter3(core::int? value) → void {}
+  method methodAndFinalFieldAndSetter3() → core::int? {}
+  set methodAndFinalFieldAndSetter4(core::int? value) → void {}
+  method methodAndSetter1() → core::int? {}
+  set methodAndSetter1(core::int? value) → void {}
+  method methodAndSetter2(core::int? value) → void {}
+  set methodAndSetter2(dynamic #synthetic) → void {
+    invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:54:28: Error: A setter should have exactly one formal parameter.
+  int? set methodAndSetter2() {}
+                           ^";
+    {}
+  }
+}
+static method test(self::Class c) → dynamic {
+  invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:80:5: Error: The setter 'methodAndField1' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'methodAndField1'.
+  c.methodAndField1 = c.methodAndField1;
+    ^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndField1 = invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:80:25: Error: The getter 'methodAndField1' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndField1'.
+  c.methodAndField1 = c.methodAndField1;
+                        ^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndField1;
+  invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:81:5: Error: The setter 'methodAndField2' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'methodAndField2'.
+  c.methodAndField2 = c.methodAndField2;
+    ^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndField2 = invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:81:25: Error: The getter 'methodAndField2' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndField2'.
+  c.methodAndField2 = c.methodAndField2;
+                        ^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndField2;
+  invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:82:5: Error: The getter 'methodAndFinalField1' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFinalField1'.
+  c.methodAndFinalField1;
+    ^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndFinalField1;
+  invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:83:5: Error: The getter 'methodAndFinalField2' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFinalField2'.
+  c.methodAndFinalField2;
+    ^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndFinalField2;
+  invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:84:5: Error: The setter 'methodAndFieldAndSetter1' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'methodAndFieldAndSetter1'.
+  c.methodAndFieldAndSetter1 = c.methodAndFieldAndSetter1;
+    ^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndFieldAndSetter1 = invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:84:34: Error: The getter 'methodAndFieldAndSetter1' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFieldAndSetter1'.
+  c.methodAndFieldAndSetter1 = c.methodAndFieldAndSetter1;
+                                 ^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndFieldAndSetter1;
+  invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:85:5: Error: The setter 'methodAndFieldAndSetter2' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'methodAndFieldAndSetter2'.
+  c.methodAndFieldAndSetter2 = c.methodAndFieldAndSetter2;
+    ^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndFieldAndSetter2 = invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:85:34: Error: The getter 'methodAndFieldAndSetter2' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFieldAndSetter2'.
+  c.methodAndFieldAndSetter2 = c.methodAndFieldAndSetter2;
+                                 ^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndFieldAndSetter2;
+  invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:86:5: Error: The setter 'methodAndFieldAndSetter3' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'methodAndFieldAndSetter3'.
+  c.methodAndFieldAndSetter3 = c.methodAndFieldAndSetter3;
+    ^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndFieldAndSetter3 = invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:86:34: Error: The getter 'methodAndFieldAndSetter3' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFieldAndSetter3'.
+  c.methodAndFieldAndSetter3 = c.methodAndFieldAndSetter3;
+                                 ^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndFieldAndSetter3;
+  invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:87:5: Error: The setter 'methodAndFieldAndSetter4' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'methodAndFieldAndSetter4'.
+  c.methodAndFieldAndSetter4 = c.methodAndFieldAndSetter4;
+    ^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndFieldAndSetter4 = invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:87:34: Error: The getter 'methodAndFieldAndSetter4' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFieldAndSetter4'.
+  c.methodAndFieldAndSetter4 = c.methodAndFieldAndSetter4;
+                                 ^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndFieldAndSetter4;
+  c.{self::Class::methodAndFinalFieldAndSetter1} = invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:88:39: Error: The getter 'methodAndFinalFieldAndSetter1' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFinalFieldAndSetter1'.
+  c.methodAndFinalFieldAndSetter1 = c.methodAndFinalFieldAndSetter1;
+                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndFinalFieldAndSetter1 as{TypeError,ForDynamic,ForNonNullableByDefault} core::int?;
+  c.{self::Class::methodAndFinalFieldAndSetter2} = invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:89:39: Error: The getter 'methodAndFinalFieldAndSetter2' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFinalFieldAndSetter2'.
+  c.methodAndFinalFieldAndSetter2 = c.methodAndFinalFieldAndSetter2;
+                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndFinalFieldAndSetter2 as{TypeError,ForDynamic,ForNonNullableByDefault} core::int?;
+  c.{self::Class::methodAndFinalFieldAndSetter3} = invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:90:39: Error: The getter 'methodAndFinalFieldAndSetter3' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFinalFieldAndSetter3'.
+  c.methodAndFinalFieldAndSetter3 = c.methodAndFinalFieldAndSetter3;
+                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndFinalFieldAndSetter3 as{TypeError,ForDynamic,ForNonNullableByDefault} core::int?;
+  c.{self::Class::methodAndFinalFieldAndSetter4} = invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:91:39: Error: The getter 'methodAndFinalFieldAndSetter4' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'methodAndFinalFieldAndSetter4'.
+  c.methodAndFinalFieldAndSetter4 = c.methodAndFinalFieldAndSetter4;
+                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.methodAndFinalFieldAndSetter4 as{TypeError,ForDynamic,ForNonNullableByDefault} core::int?;
+  c.{self::Class::methodAndSetter1} = invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:92:26: Error: A value of type 'int? Function()' can't be assigned to a variable of type 'int?'.
+  c.methodAndSetter1 = c.methodAndSetter1;
+                         ^" in c.{self::Class::methodAndSetter1}{() → core::int?} as{TypeError,ForNonNullableByDefault} core::int?;
+  c.{self::Class::methodAndSetter2} = c.{self::Class::methodAndSetter2}{(core::int?) → void};
+  c.{self::Class::fieldAndSetter1} = c.{self::Class::fieldAndSetter1}{core::int?};
+  c.{self::Class::fieldAndSetter2} = c.{self::Class::fieldAndSetter2}{core::int?};
+  invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:96:5: Error: The setter 'fieldAndFinalFieldAndSetter1' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'fieldAndFinalFieldAndSetter1'.
+  c.fieldAndFinalFieldAndSetter1 = c.fieldAndFinalFieldAndSetter1;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.fieldAndFinalFieldAndSetter1 = invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:96:38: Error: The getter 'fieldAndFinalFieldAndSetter1' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'fieldAndFinalFieldAndSetter1'.
+  c.fieldAndFinalFieldAndSetter1 = c.fieldAndFinalFieldAndSetter1;
+                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.fieldAndFinalFieldAndSetter1;
+  invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:97:5: Error: The setter 'fieldAndFinalFieldAndSetter2' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'fieldAndFinalFieldAndSetter2'.
+  c.fieldAndFinalFieldAndSetter2 = c.fieldAndFinalFieldAndSetter2;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.fieldAndFinalFieldAndSetter2 = invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:97:38: Error: The getter 'fieldAndFinalFieldAndSetter2' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'fieldAndFinalFieldAndSetter2'.
+  c.fieldAndFinalFieldAndSetter2 = c.fieldAndFinalFieldAndSetter2;
+                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.fieldAndFinalFieldAndSetter2;
+  invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:98:5: Error: The setter 'fieldAndFinalFieldAndSetter3' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'fieldAndFinalFieldAndSetter3'.
+  c.fieldAndFinalFieldAndSetter3 = c.fieldAndFinalFieldAndSetter3;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.fieldAndFinalFieldAndSetter3 = invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:98:38: Error: The getter 'fieldAndFinalFieldAndSetter3' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'fieldAndFinalFieldAndSetter3'.
+  c.fieldAndFinalFieldAndSetter3 = c.fieldAndFinalFieldAndSetter3;
+                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.fieldAndFinalFieldAndSetter3;
+  invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:99:5: Error: The setter 'fieldAndFinalFieldAndSetter4' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'fieldAndFinalFieldAndSetter4'.
+  c.fieldAndFinalFieldAndSetter4 = c.fieldAndFinalFieldAndSetter4;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.fieldAndFinalFieldAndSetter4 = invalid-expression "pkg/front_end/testcases/nnbd/instance_duplicates.dart:99:38: Error: The getter 'fieldAndFinalFieldAndSetter4' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/instance_duplicates.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'fieldAndFinalFieldAndSetter4'.
+  c.fieldAndFinalFieldAndSetter4 = c.fieldAndFinalFieldAndSetter4;
+                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.fieldAndFinalFieldAndSetter4;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/intersection_types.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/intersection_types.dart.weak.modular.expect
new file mode 100644
index 0000000..9723009
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/intersection_types.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class B extends self::A {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C
+    : super self::B::•()
+    ;
+}
+class Foo<T extends self::A?> extends core::Object {
+  synthetic constructor •() → self::Foo<self::Foo::T%>
+    : super core::Object::•()
+    ;
+  method doPromotionsToNullable(covariant-by-class self::Foo::T% t) → dynamic {
+    if(t is{ForNonNullableByDefault} self::B?) {
+      self::Foo::T% bar = t{self::Foo::T% & self::B? /* '%' & '?' = '%' */};
+      if(t{self::Foo::T% & self::B? /* '%' & '?' = '%' */} is{ForNonNullableByDefault} self::C?) {
+        self::Foo::T% baz = t{self::Foo::T% & self::C? /* '%' & '?' = '%' */};
+      }
+    }
+  }
+  method doPromotionsToNonNullable(covariant-by-class self::Foo::T% t) → dynamic {
+    if(t is{ForNonNullableByDefault} self::B) {
+      self::Foo::T% bar = t{self::Foo::T% & self::B /* '%' & '!' = '!' */};
+      if(t{self::Foo::T% & self::B /* '%' & '!' = '!' */} is{ForNonNullableByDefault} self::C) {
+        self::Foo::T baz = t{self::Foo::T & self::C /* '!' & '!' = '!' */};
+      }
+    }
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/invalid_combined_member_signature.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/invalid_combined_member_signature.dart.weak.modular.expect
new file mode 100644
index 0000000..c80806c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/invalid_combined_member_signature.dart.weak.modular.expect
@@ -0,0 +1,52 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/invalid_combined_member_signature.dart:11:16: Error: Type 'Unresolved' not found.
+//   void method1(Unresolved c) {}
+//                ^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/invalid_combined_member_signature.dart:17:16: Error: Class 'D' inherits multiple members named 'method2' with incompatible signatures.
+// Try adding a declaration of 'method2' to 'D'.
+// abstract class D implements A, B {}
+//                ^
+// pkg/front_end/testcases/nnbd/invalid_combined_member_signature.dart:7:8: Context: This is one of the overridden members.
+//   void method2(int a, int b) {}
+//        ^^^^^^^
+// pkg/front_end/testcases/nnbd/invalid_combined_member_signature.dart:12:8: Context: This is one of the overridden members.
+//   void method2(int a) {}
+//        ^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/invalid_combined_member_signature.dart:11:16: Error: 'Unresolved' isn't a type.
+//   void method1(Unresolved c) {}
+//                ^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method method1(self::C c) → void {}
+  method method2(core::int a, core::int b) → void {}
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+  method method1(invalid-type c) → void {}
+  method method2(core::int a) → void {}
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+abstract class D extends core::Object implements self::A, self::B {
+  synthetic constructor •() → self::D
+    : super core::Object::•()
+    ;
+  abstract member-signature method method1(invalid-type c) → void; -> self::A::method1
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue34803.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue34803.dart.weak.modular.expect
new file mode 100644
index 0000000..fc4163c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue34803.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue34803.dart:7:9: Error: Type variables can't have generic function types in their bounds.
+// class A<X extends G<num>> {}
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef G<invariant X extends core::Object? = dynamic> = <Y extends X% = dynamic>() → void;
+class A<X extends <Y extends core::num = dynamic>() → void = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X>
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue39659.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue39659.dart.weak.modular.expect
new file mode 100644
index 0000000..910ce4f
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue39659.dart.weak.modular.expect
@@ -0,0 +1,19 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue39659.dart:8:9: Error: Can't throw a value of 'String?' since it is neither dynamic nor non-nullable.
+//   throw bar();
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method foo() → dynamic {
+  invalid-expression "pkg/front_end/testcases/nnbd/issue39659.dart:8:9: Error: Can't throw a value of 'String?' since it is neither dynamic nor non-nullable.
+  throw bar();
+        ^";
+}
+static method bar() → core::String?
+  return "asdf";
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue39822.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue39822.dart.weak.modular.expect
new file mode 100644
index 0000000..5ffa759
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue39822.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:_internal" as _in;
+import "dart:core" as core;
+
+static method foo(Null x) → dynamic {
+  self::bar(let final Never #t1 = x! in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."));
+}
+static method bar(core::int y) → dynamic {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue40093.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue40093.dart.weak.modular.expect
new file mode 100644
index 0000000..f083d82
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue40093.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue40093.dart:6:8: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   for (late int i = 0; i < 10; ++i) {
+//        ^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40093.dart:9:8: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   for (late int i in <int>[]) {
+//        ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method error() → dynamic {
+  for (core::int i = 0; i.{core::num::<}(10){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+    core::print(i);
+  }
+  for (core::int i in <core::int>[]) {
+    core::print(i);
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue40134.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue40134.dart.weak.modular.expect
new file mode 100644
index 0000000..4f69681
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue40134.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class GenericMethodBounds<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::GenericMethodBounds<self::GenericMethodBounds::T%>
+    : super core::Object::•()
+    ;
+  get t() → core::Type
+    return self::GenericMethodBounds::T%;
+  method foo<covariant-by-class E extends self::GenericMethodBounds::T%>() → self::GenericMethodBounds<self::GenericMethodBounds::foo::E%>
+    return new self::GenericMethodBounds::•<self::GenericMethodBounds::foo::E%>();
+  method bar<E extends (self::GenericMethodBounds::T%) → void>() → self::GenericMethodBounds<self::GenericMethodBounds::bar::E>
+    return new self::GenericMethodBounds::•<self::GenericMethodBounds::bar::E>();
+}
+class GenericMethodBoundsDerived extends self::GenericMethodBounds<core::num> {
+  synthetic constructor •() → self::GenericMethodBoundsDerived
+    : super self::GenericMethodBounds::•()
+    ;
+  method foo<covariant-by-class E extends core::num>() → self::GenericMethodBounds<self::GenericMethodBoundsDerived::foo::E>
+    return new self::GenericMethodBounds::•<self::GenericMethodBoundsDerived::foo::E>();
+  method bar<E extends (core::num) → void>() → self::GenericMethodBounds<self::GenericMethodBoundsDerived::bar::E>
+    return new self::GenericMethodBounds::•<self::GenericMethodBoundsDerived::bar::E>();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue40600.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue40600.dart.weak.modular.expect
new file mode 100644
index 0000000..90f9674
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue40600.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class B<Y extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::Y%>
+    : super core::Object::•()
+    ;
+  method bar(covariant-by-class FutureOr<self::B::Y%>y) → dynamic {}
+}
+class A<X extends core::Object? = dynamic> extends core::Object {
+  covariant-by-class final field self::B<self::A::X%> b = new self::B::•<self::A::X%>();
+  synthetic constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+  method foo([covariant-by-class FutureOr<self::A::X%>? x = #C1]) → dynamic {
+    if(x is{ForNonNullableByDefault} asy::Future<self::A::X%>) {
+      this.{self::A::b}{self::B<self::A::X%>}.{self::B::bar}(x{asy::Future<self::A::X%>} as{ForNonNullableByDefault} FutureOr<self::A::X%>){(FutureOr<self::A::X%>) → dynamic};
+    }
+  }
+}
+class C<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T%>
+    : super core::Object::•()
+    ;
+  method baz<covariant-by-class X extends FutureOr<self::C::T%>>(covariant-by-class FutureOr<self::C::T%>x) → FutureOr<self::C::T%>
+    return x;
+}
+class D<T extends core::Object? = dynamic> extends self::C<self::D::T%> {
+  synthetic constructor •() → self::D<self::D::T%>
+    : super self::C::•()
+    ;
+  method baz<covariant-by-class X extends FutureOr<self::D::T%>>(covariant-by-class FutureOr<self::D::T%>x) → FutureOr<self::D::T%>
+    return x;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/issue40601.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue40601.dart.weak.modular.expect
new file mode 100644
index 0000000..8fd86fa
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue40601.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class A<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+  abstract method baz() → self::A::T%;
+  method bar(covariant-by-class self::A::T% value) → dynamic {}
+  method foo() → dynamic {
+    late self::A::T% value;
+    () → dynamic result = () → dynamic => this.{self::A::bar}(value){(self::A::T%) → dynamic};
+    (() → Null {
+      value = this.{self::A::baz}(){() → self::A::T%};
+    })(){() → Null};
+    return result;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue40805.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue40805.dart.weak.modular.expect
new file mode 100644
index 0000000..0eacd23
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue40805.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  late covariant-by-declaration final [setter] field core::int x;
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+class D extends self::C {
+  synthetic constructor •() → self::D
+    : super self::C::•()
+    ;
+  set x(covariant-by-declaration core::num value) → void {
+    super.{self::C::x} = value.{core::num::toInt}(){() → core::int};
+  }
+}
+static method main() → dynamic {
+  new self::D::•().{self::D::x} = 3.14;
+}
diff --git a/pkg/front_end/testcases/nnbd/issue40945.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue40945.dart.weak.modular.expect
new file mode 100644
index 0000000..f441fd5
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue40945.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue40945.dart:7:15: Error: The type 'dynamic' of the getter 'C.test' is not a subtype of the type 'int' of the setter 'C.test'.
+//   dynamic get test => 3.14;
+//               ^^^^
+// pkg/front_end/testcases/nnbd/issue40945.dart:6:12: Context: This is the declaration of the setter 'C.test'.
+//   void set test(int v) {}
+//            ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  set test(core::int v) → void {}
+  get test() → dynamic
+    return 3.14;
+}
+static method test() → dynamic {
+  self::C c = new self::C::•();
+  c.{self::C::test} = 1;
+  c.{self::C::test}{dynamic};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue40951.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue40951.dart.weak.modular.expect
new file mode 100644
index 0000000..42868d7
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue40951.dart.weak.modular.expect
@@ -0,0 +1,206 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:9:3: Error: This constructor should initialize field 'field1' because its type 'num' doesn't allow null.
+//   A() {}
+//   ^
+// pkg/front_end/testcases/nnbd/issue40951.dart:6:7: Context: 'field1' is defined here.
+//   num field1;
+//       ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:9:3: Error: This constructor should initialize field 'field2' because its type 'num' doesn't allow null.
+//   A() {}
+//   ^
+// pkg/front_end/testcases/nnbd/issue40951.dart:7:7: Context: 'field2' is defined here.
+//   num field2;
+//       ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:10:3: Error: This constructor should initialize field 'field1' because its type 'num' doesn't allow null.
+//   A.foo() {}
+//   ^
+// pkg/front_end/testcases/nnbd/issue40951.dart:6:7: Context: 'field1' is defined here.
+//   num field1;
+//       ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:10:3: Error: This constructor should initialize field 'field2' because its type 'num' doesn't allow null.
+//   A.foo() {}
+//   ^
+// pkg/front_end/testcases/nnbd/issue40951.dart:7:7: Context: 'field2' is defined here.
+//   num field2;
+//       ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:11:3: Error: This constructor should initialize field 'field2' because its type 'num' doesn't allow null.
+//   A.bar(this.field1) {}
+//   ^
+// pkg/front_end/testcases/nnbd/issue40951.dart:7:7: Context: 'field2' is defined here.
+//   num field2;
+//       ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:19:3: Error: This constructor should initialize field 'field1' because its type 'num' doesn't allow null.
+//   B() {}
+//   ^
+// pkg/front_end/testcases/nnbd/issue40951.dart:16:7: Context: 'field1' is defined here.
+//   num field1;
+//       ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:19:3: Error: This constructor should initialize field 'field2' because its type 'num' doesn't allow null.
+//   B() {}
+//   ^
+// pkg/front_end/testcases/nnbd/issue40951.dart:17:7: Context: 'field2' is defined here.
+//   num field2;
+//       ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:20:3: Error: This constructor should initialize field 'field1' because its type 'num' doesn't allow null.
+//   B.foo() {}
+//   ^
+// pkg/front_end/testcases/nnbd/issue40951.dart:16:7: Context: 'field1' is defined here.
+//   num field1;
+//       ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:20:3: Error: This constructor should initialize field 'field2' because its type 'num' doesn't allow null.
+//   B.foo() {}
+//   ^
+// pkg/front_end/testcases/nnbd/issue40951.dart:17:7: Context: 'field2' is defined here.
+//   num field2;
+//       ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:21:3: Error: This constructor should initialize field 'field2' because its type 'num' doesn't allow null.
+//   B.bar(this.field1) {}
+//   ^
+// pkg/front_end/testcases/nnbd/issue40951.dart:17:7: Context: 'field2' is defined here.
+//   num field2;
+//       ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:29:3: Error: Final field 'field1' is not initialized by this constructor.
+// Try to initialize the field using an initializing formal or a field initializer.
+//   C() {}
+//   ^
+// pkg/front_end/testcases/nnbd/issue40951.dart:26:14: Context: 'field1' is defined here.
+//   final num? field1;
+//              ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:29:3: Error: Final field 'field2' is not initialized by this constructor.
+// Try to initialize the field using an initializing formal or a field initializer.
+//   C() {}
+//   ^
+// pkg/front_end/testcases/nnbd/issue40951.dart:27:14: Context: 'field2' is defined here.
+//   final num? field2;
+//              ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:30:3: Error: Final field 'field1' is not initialized by this constructor.
+// Try to initialize the field using an initializing formal or a field initializer.
+//   C.foo() {}
+//   ^^^
+// pkg/front_end/testcases/nnbd/issue40951.dart:26:14: Context: 'field1' is defined here.
+//   final num? field1;
+//              ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:30:3: Error: Final field 'field2' is not initialized by this constructor.
+// Try to initialize the field using an initializing formal or a field initializer.
+//   C.foo() {}
+//   ^^^
+// pkg/front_end/testcases/nnbd/issue40951.dart:27:14: Context: 'field2' is defined here.
+//   final num? field2;
+//              ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:31:3: Error: Final field 'field2' is not initialized by this constructor.
+// Try to initialize the field using an initializing formal or a field initializer.
+//   C.bar(this.field1) {}
+//   ^^^
+// pkg/front_end/testcases/nnbd/issue40951.dart:27:14: Context: 'field2' is defined here.
+//   final num? field2;
+//              ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:39:3: Error: Final field 'field1' is not initialized by this constructor.
+// Try to initialize the field using an initializing formal or a field initializer.
+//   D() {}
+//   ^
+// pkg/front_end/testcases/nnbd/issue40951.dart:36:14: Context: 'field1' is defined here.
+//   final num? field1;
+//              ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:39:3: Error: Final field 'field2' is not initialized by this constructor.
+// Try to initialize the field using an initializing formal or a field initializer.
+//   D() {}
+//   ^
+// pkg/front_end/testcases/nnbd/issue40951.dart:37:14: Context: 'field2' is defined here.
+//   final num? field2;
+//              ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:40:3: Error: Final field 'field1' is not initialized by this constructor.
+// Try to initialize the field using an initializing formal or a field initializer.
+//   D.foo() {}
+//   ^^^
+// pkg/front_end/testcases/nnbd/issue40951.dart:36:14: Context: 'field1' is defined here.
+//   final num? field1;
+//              ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:40:3: Error: Final field 'field2' is not initialized by this constructor.
+// Try to initialize the field using an initializing formal or a field initializer.
+//   D.foo() {}
+//   ^^^
+// pkg/front_end/testcases/nnbd/issue40951.dart:37:14: Context: 'field2' is defined here.
+//   final num? field2;
+//              ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue40951.dart:41:3: Error: Final field 'field2' is not initialized by this constructor.
+// Try to initialize the field using an initializing formal or a field initializer.
+//   D.bar(this.field1) {}
+//   ^^^
+// pkg/front_end/testcases/nnbd/issue40951.dart:37:14: Context: 'field2' is defined here.
+//   final num? field2;
+//              ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::num field1;
+  field core::num field2;
+  constructor •() → self::A
+    : self::A::field2 = null, self::A::field1 = null, super core::Object::•() {}
+  constructor foo() → self::A
+    : self::A::field2 = null, self::A::field1 = null, super core::Object::•() {}
+  constructor bar(core::num field1) → self::A
+    : self::A::field2 = null, self::A::field1 = field1, super core::Object::•() {}
+  constructor baz(core::num field1, core::num field2) → self::A
+    : self::A::field1 = field1, self::A::field2 = field2, super core::Object::•() {}
+}
+abstract class B extends core::Object {
+  field core::num field1;
+  field core::num field2;
+  constructor •() → self::B
+    : self::B::field2 = null, self::B::field1 = null, super core::Object::•() {}
+  constructor foo() → self::B
+    : self::B::field2 = null, self::B::field1 = null, super core::Object::•() {}
+  constructor bar(core::num field1) → self::B
+    : self::B::field2 = null, self::B::field1 = field1, super core::Object::•() {}
+  constructor baz(core::num field1, core::num field2) → self::B
+    : self::B::field1 = field1, self::B::field2 = field2, super core::Object::•() {}
+}
+class C extends core::Object {
+  final field core::num? field1;
+  final field core::num? field2;
+  constructor •() → self::C
+    : self::C::field2 = null, self::C::field1 = null, super core::Object::•() {}
+  constructor foo() → self::C
+    : self::C::field2 = null, self::C::field1 = null, super core::Object::•() {}
+  constructor bar(core::num? field1) → self::C
+    : self::C::field2 = null, self::C::field1 = field1, super core::Object::•() {}
+  constructor baz(core::num? field1, core::num? field2) → self::C
+    : self::C::field1 = field1, self::C::field2 = field2, super core::Object::•() {}
+}
+abstract class D extends core::Object {
+  final field core::num? field1;
+  final field core::num? field2;
+  constructor •() → self::D
+    : self::D::field2 = null, self::D::field1 = null, super core::Object::•() {}
+  constructor foo() → self::D
+    : self::D::field2 = null, self::D::field1 = null, super core::Object::•() {}
+  constructor bar(core::num? field1) → self::D
+    : self::D::field2 = null, self::D::field1 = field1, super core::Object::•() {}
+  constructor baz(core::num? field1, core::num? field2) → self::D
+    : self::D::field1 = field1, self::D::field2 = field2, super core::Object::•() {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue40954.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue40954.dart.weak.modular.expect
new file mode 100644
index 0000000..cbfe037
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue40954.dart.weak.modular.expect
@@ -0,0 +1,64 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue40954.dart:8:31: Error: The parameter 'a' can't have a value of 'null' because of its type 'A', but the implicit default value is 'null'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue40954.dart'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   static void test1(var v, [A a]) {}
+//                               ^
+//
+// pkg/front_end/testcases/nnbd/issue40954.dart:10:31: Error: The parameter 'a' can't have a value of 'null' because of its type 'A', but the implicit default value is 'null'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue40954.dart'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   static void test2(var v, {A a}) {}
+//                               ^
+//
+// pkg/front_end/testcases/nnbd/issue40954.dart:12:25: Error: The parameter 'a' can't have a value of 'null' because of its type 'A', but the implicit default value is 'null'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue40954.dart'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   void test11(var v, [A a]) {}
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/issue40954.dart:14:25: Error: The parameter 'a' can't have a value of 'null' because of its type 'A', but the implicit default value is 'null'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue40954.dart'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   void test22(var v, {A a}) {}
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/issue40954.dart:17:22: Error: The parameter 'a' can't have a value of 'null' because of its type 'A', but the implicit default value is 'null'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue40954.dart'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// void test1(var v, [A a]) {}
+//                      ^
+//
+// pkg/front_end/testcases/nnbd/issue40954.dart:19:22: Error: The parameter 'a' can't have a value of 'null' because of its type 'A', but the implicit default value is 'null'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue40954.dart'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// void test2(var v, {A a}) {}
+//                      ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  static method test1(dynamic v, [self::A a = #C1]) → void {}
+  static method test2(dynamic v, {self::A a = #C1}) → void {}
+  method test11(dynamic v, [self::A a = #C1]) → void {}
+  method test22(dynamic v, {self::A a = #C1}) → void {}
+}
+static method test1(dynamic v, [self::A a = #C1]) → void {}
+static method test2(dynamic v, {self::A a = #C1}) → void {}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/issue41102.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41102.dart.weak.modular.expect
new file mode 100644
index 0000000..e9cdc2d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41102.dart.weak.modular.expect
@@ -0,0 +1,130 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue41102.dart:15:12: Warning: Operand of null-aware operation '?.' has type 'List<dynamic>' which excludes null.
+//  - 'List' is from 'dart:core'.
+// final s2 = s1?.length;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/issue41102.dart:17:36: Error: The value 'null' can't be assigned to the parameter type 'int' because 'int' is not nullable.
+// final s3 = new List<int>.filled(2, null);
+//                                    ^
+//
+// pkg/front_end/testcases/nnbd/issue41102.dart:22:5: Error: Switch case may fall through to the next case.
+//     case 0:
+//     ^
+//
+// pkg/front_end/testcases/nnbd/issue41102.dart:25:10: Error: Type 'String' of the case expression is not a subtype of type 'int' of this switch expression.
+//     case '':
+//          ^
+// pkg/front_end/testcases/nnbd/issue41102.dart:21:11: Context: The switch expression is here.
+//   switch (e) {
+//           ^
+//
+// pkg/front_end/testcases/nnbd/issue41102.dart:31:15: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+// final s6 = s5 + 0;
+//               ^
+//
+// pkg/front_end/testcases/nnbd/issue41102.dart:35:14: Error: Operator '[]' cannot be called on 'List<dynamic>?' because it is potentially null.
+//  - 'List' is from 'dart:core'.
+// final s8 = s7[0];
+//              ^
+//
+// pkg/front_end/testcases/nnbd/issue41102.dart:37:14: Error: Operator '[]=' cannot be called on 'List<dynamic>?' because it is potentially null.
+//  - 'List' is from 'dart:core'.
+// final s9 = s7[0] = 0;
+//              ^
+//
+// pkg/front_end/testcases/nnbd/issue41102.dart:39:16: Error: Property 'length' cannot be accessed on 'List<dynamic>?' because it is potentially null.
+//  - 'List' is from 'dart:core'.
+// Try accessing using ?. instead.
+// final s10 = s7.length;
+//                ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue41102.dart:41:16: Error: Property 'length' cannot be accessed on 'List<dynamic>?' because it is potentially null.
+//  - 'List' is from 'dart:core'.
+// Try accessing using ?. instead.
+// final s11 = s7.length = 0;
+//                ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue41102.dart:43:13: Error: Operator 'unary-' cannot be called on 'int?' because it is potentially null.
+// final s12 = -s5;
+//             ^
+//
+// pkg/front_end/testcases/nnbd/issue41102.dart:47:18: Error: Can't use an expression of type 'int Function()?' as a function because it's potentially null.
+// Try calling using ?.call instead.
+// final s14 = (s13)();
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/issue41102.dart:49:19: Error: Can't throw a value of 'Null' since it is neither dynamic nor non-nullable.
+// final s15 = throw null;
+//                   ^
+//
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "dart:async";
+
+static final field asy::StreamTransformer<core::Object?, core::Object?> t = new asy::_StreamHandlerTransformer::•<core::Object?, core::Object?>(handleData: (core::Object? data, asy::EventSink<core::Object?> sink) → void => asy::Future::microtask<void>(() → void => sink.{asy::EventSink::add}(data){(core::Object?) → void}), handleDone: (asy::EventSink<core::Object?> sink) → void => asy::Future::microtask<void>(() → void => sink.{asy::EventSink::close}(){() → void}));
+static final field core::List<dynamic> s1 = <dynamic>[];
+static final field core::int? s2 = let final core::List<dynamic> #t1 = self::s1 in #t1 == null ?{core::int?} null : #t1.{core::List::length}{core::int};
+static final field core::List<core::int> s3 = core::List::filled<core::int>(2, invalid-expression "pkg/front_end/testcases/nnbd/issue41102.dart:17:36: Error: The value 'null' can't be assigned to the parameter type 'int' because 'int' is not nullable.
+final s3 = new List<int>.filled(2, null);
+                                   ^" in null as{TypeError,ForNonNullableByDefault} core::int);
+static final field dynamic s4 = (() → Null {
+  core::int e = 0;
+  switch(e) {
+    #L1:
+    case #C1:
+      {
+        core::print("fallthrough");
+      }
+    #L2:
+    case #C2:
+    case #C3:
+      {}
+  }
+})(){() → Null};
+static field core::int? s5;
+static final field core::num s6 = invalid-expression "pkg/front_end/testcases/nnbd/issue41102.dart:31:15: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+final s6 = s5 + 0;
+              ^" in self::s5.{core::num::+}(0){(core::num) → core::num};
+static field core::List<dynamic>? s7;
+static final field dynamic s8 = invalid-expression "pkg/front_end/testcases/nnbd/issue41102.dart:35:14: Error: Operator '[]' cannot be called on 'List<dynamic>?' because it is potentially null.
+ - 'List' is from 'dart:core'.
+final s8 = s7[0];
+             ^" in self::s7.{core::List::[]}{<nullable>}.(0){(core::int) → dynamic};
+static final field core::int s9 = let final core::List<dynamic>? #t2 = self::s7 in let final core::int #t3 = 0 in let final core::int #t4 = 0 in let final void #t5 = invalid-expression "pkg/front_end/testcases/nnbd/issue41102.dart:37:14: Error: Operator '[]=' cannot be called on 'List<dynamic>?' because it is potentially null.
+ - 'List' is from 'dart:core'.
+final s9 = s7[0] = 0;
+             ^" in #t2.{core::List::[]=}{<nullable>}.(#t3, #t4){(core::int, dynamic) → void} in #t4;
+static final field core::int s10 = invalid-expression "pkg/front_end/testcases/nnbd/issue41102.dart:39:16: Error: Property 'length' cannot be accessed on 'List<dynamic>?' because it is potentially null.
+ - 'List' is from 'dart:core'.
+Try accessing using ?. instead.
+final s10 = s7.length;
+               ^^^^^^" in self::s7.{core::List::length}{<nullable>}.{core::int};
+static final field core::int s11 = invalid-expression "pkg/front_end/testcases/nnbd/issue41102.dart:41:16: Error: Property 'length' cannot be accessed on 'List<dynamic>?' because it is potentially null.
+ - 'List' is from 'dart:core'.
+Try accessing using ?. instead.
+final s11 = s7.length = 0;
+               ^^^^^^" in self::s7.{core::List::length}{<nullable>}. = 0;
+static final field core::int s12 = invalid-expression "pkg/front_end/testcases/nnbd/issue41102.dart:43:13: Error: Operator 'unary-' cannot be called on 'int?' because it is potentially null.
+final s12 = -s5;
+            ^" in self::s5.{core::int::unary-}(){() → core::int};
+static field () →? core::int s13;
+static final field core::int s14 = invalid-expression "pkg/front_end/testcases/nnbd/issue41102.dart:47:18: Error: Can't use an expression of type 'int Function()?' as a function because it's potentially null.
+Try calling using ?.call instead.
+final s14 = (s13)();
+                 ^" in self::s13{<nullable>}.(){() →? core::int};
+static final field Never s15 = invalid-expression "pkg/front_end/testcases/nnbd/issue41102.dart:49:19: Error: Can't throw a value of 'Null' since it is neither dynamic nor non-nullable.
+final s15 = throw null;
+                  ^" as{TypeError,ForDynamic,ForNonNullableByDefault} Never;
+static method main() → void {}
+
+constants  {
+  #C1 = 0
+  #C2 = 1
+  #C3 = ""
+}
diff --git a/pkg/front_end/testcases/nnbd/issue41103.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41103.dart.weak.modular.expect
new file mode 100644
index 0000000..d5d245a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41103.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "dart:async";
+
+static final field asy::StreamTransformer<core::Object?, core::Object?> t = new asy::_StreamHandlerTransformer::•<core::Object?, core::Object?>(handleData: (core::Object? data, asy::EventSink<core::Object?> sink) → void => asy::Future::microtask<void>(() → void => sink.{asy::EventSink::add}(data){(core::Object?) → void}), handleDone: (asy::EventSink<core::Object?> sink) → void => asy::Future::microtask<void>(() → void => sink.{asy::EventSink::close}(){() → void}));
+static method main() → void {}
diff --git a/pkg/front_end/testcases/nnbd/issue41108.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41108.dart.weak.modular.expect
new file mode 100644
index 0000000..3874c5a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41108.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue41108.dart:6:12: Error: A value of type 'List<dynamic>?' can't be assigned to a variable of type 'List<dynamic>' because 'List<dynamic>?' is nullable and 'List<dynamic>' isn't.
+//  - 'List' is from 'dart:core'.
+//   List y = await l(); // should be a List?
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+static method test() → dynamic async {
+  core::List<dynamic> y = invalid-expression "pkg/front_end/testcases/nnbd/issue41108.dart:6:12: Error: A value of type 'List<dynamic>?' can't be assigned to a variable of type 'List<dynamic>' because 'List<dynamic>?' is nullable and 'List<dynamic>' isn't.
+ - 'List' is from 'dart:core'.
+  List y = await l(); // should be a List?
+           ^" in await self::l() as{TypeError,ForNonNullableByDefault} core::List<dynamic>;
+}
+static method l() → asy::Future<core::List<dynamic>>?
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue41114.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41114.dart.weak.modular.expect
new file mode 100644
index 0000000..467d91a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41114.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic async {
+  core::List<core::String>? a = <core::String>[] as{ForNonNullableByDefault} core::List<core::String>?;
+  core::Iterable<core::String>? b = let final core::List<core::String>? #t1 = a in #t1 == null ?{core::Iterable<core::String>?} null : #t1{core::List<core::String>}.{core::Iterable::map}<core::String>((core::String e) → core::String => e){((core::String) → core::String) → core::Iterable<core::String>};
+  core::Iterable<core::String>? i = let final core::Iterable<core::String>? #t2 = b in #t2 == null ?{core::Iterable<core::String>?} a : #t2{core::Iterable<core::String>};
+  core::print(i);
+}
diff --git a/pkg/front_end/testcases/nnbd/issue41156.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41156.dart.weak.modular.expect
new file mode 100644
index 0000000..9940f1b
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41156.dart.weak.modular.expect
@@ -0,0 +1,155 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue41156.dart:39:29: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+//   String Function(int) x2 = (int v) /* error */ {
+//                             ^
+//
+// pkg/front_end/testcases/nnbd/issue41156.dart:44:29: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+//   String Function(int) x3 = (int v) /* error */ {
+//                             ^
+//
+// pkg/front_end/testcases/nnbd/issue41156.dart:49:29: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+//   String Function(int) x5 = (int v) /* error */ {
+//                             ^
+//
+// pkg/front_end/testcases/nnbd/issue41156.dart:54:29: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+//   String Function(int) x6 = (int v) /* error */ {
+//                             ^
+//
+// pkg/front_end/testcases/nnbd/issue41156.dart:59:37: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+//   Future<String> Function(int) y2 = (int v) async /* error */ {
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/issue41156.dart:64:37: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+//   Future<String> Function(int) y3 = (int v) async /* error */ {
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/issue41156.dart:69:37: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+//   Future<String> Function(int) y5 = (int v) async /* error */ {
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/issue41156.dart:74:37: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+//   Future<String> Function(int) y6 = (int v) async /* error */ {
+//                                     ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+import "dart:async" as asy;
+
+static method throwing() → Never
+  return throw "";
+static method main() → void {
+  (core::int) → core::String x1 = (core::int v) → Never => throw v;
+  (core::int) → core::String x2 = (core::int v) → Never {
+    throw v;
+  };
+  (core::int) → core::String x3 = (core::int v) → Never {
+    return throw v;
+  };
+  (core::int) → core::String x4 = (core::int v) → Never => let final Never #t1 = self::throwing() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  (core::int) → core::String x5 = (core::int v) → Never {
+    let final Never #t2 = self::throwing() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  };
+  (core::int) → core::String x6 = (core::int v) → Never {
+    return let final Never #t3 = self::throwing() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  };
+  (core::int) → asy::Future<core::String> y1 = (core::int v) → asy::Future<Never> async => throw v;
+  (core::int) → asy::Future<core::String> y2 = (core::int v) → asy::Future<Never> async {
+    throw v;
+  };
+  (core::int) → asy::Future<core::String> y3 = (core::int v) → asy::Future<Never> async {
+    return throw v;
+  };
+  (core::int) → asy::Future<core::String> y4 = (core::int v) → asy::Future<Never> async => let final Never #t4 = self::throwing() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  (core::int) → asy::Future<core::String> y5 = (core::int v) → asy::Future<Never> async {
+    let final Never #t5 = self::throwing() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  };
+  (core::int) → asy::Future<core::String> y6 = (core::int v) → asy::Future<Never> async {
+    return let final Never #t6 = self::throwing() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  };
+}
+static method errors() → void async {
+  (core::int) → core::String x2 = (core::int v) → core::String {
+    try {
+      throw v;
+    }
+    on core::Object catch(final core::Object _) {
+    }
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue41156.dart:39:29: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+  String Function(int) x2 = (int v) /* error */ {
+                            ^" in null;
+  };
+  (core::int) → core::String x3 = (core::int v) → core::String {
+    try {
+      return throw v;
+    }
+    on core::Object catch(final core::Object _) {
+    }
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue41156.dart:44:29: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+  String Function(int) x3 = (int v) /* error */ {
+                            ^" in null;
+  };
+  (core::int) → core::String x5 = (core::int v) → core::String {
+    try {
+      let final Never #t7 = self::throwing() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    }
+    on core::Object catch(final core::Object _) {
+    }
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue41156.dart:49:29: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+  String Function(int) x5 = (int v) /* error */ {
+                            ^" in null;
+  };
+  (core::int) → core::String x6 = (core::int v) → core::String {
+    try {
+      return let final Never #t8 = self::throwing() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    }
+    on core::Object catch(final core::Object _) {
+    }
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue41156.dart:54:29: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+  String Function(int) x6 = (int v) /* error */ {
+                            ^" in null;
+  };
+  (core::int) → asy::Future<core::String> y2 = (core::int v) → asy::Future<core::String> async {
+    try {
+      throw v;
+    }
+    on core::Object catch(final core::Object _) {
+    }
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue41156.dart:59:37: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+  Future<String> Function(int) y2 = (int v) async /* error */ {
+                                    ^" in null;
+  };
+  (core::int) → asy::Future<core::String> y3 = (core::int v) → asy::Future<core::String> async {
+    try {
+      return throw v;
+    }
+    on core::Object catch(final core::Object _) {
+    }
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue41156.dart:64:37: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+  Future<String> Function(int) y3 = (int v) async /* error */ {
+                                    ^" in null;
+  };
+  (core::int) → asy::Future<core::String> y5 = (core::int v) → asy::Future<core::String> async {
+    try {
+      let final Never #t9 = self::throwing() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    }
+    on core::Object catch(final core::Object _) {
+    }
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue41156.dart:69:37: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+  Future<String> Function(int) y5 = (int v) async /* error */ {
+                                    ^" in null;
+  };
+  (core::int) → asy::Future<core::String> y6 = (core::int v) → asy::Future<core::String> async {
+    try {
+      return let final Never #t10 = self::throwing() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    }
+    on core::Object catch(final core::Object _) {
+    }
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue41156.dart:74:37: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+  Future<String> Function(int) y6 = (int v) async /* error */ {
+                                    ^" in null;
+  };
+}
diff --git a/pkg/front_end/testcases/nnbd/issue41273.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41273.dart.weak.modular.expect
new file mode 100644
index 0000000..0bdfe20
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41273.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:_internal" as _in;
+import "dart:core" as core;
+
+static method test(dynamic x) → void {
+  if(x is{ForNonNullableByDefault} Never) {
+    Never n1 = let final Never #t1 = (let final Never #t2 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.toString() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never n2 = let final Never #t3 = (let final Never #t4 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.runtimeType in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never n3 = let final Never #t5 = (let final Never #t6 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.someGetter in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never n4 = let final Never #t7 = (let final Never #t8 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.someMethod() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never n5 = let final Never #t9 = (let final Never #t10 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.+(let final Never #t11 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never n6 = let final Never #t12 = (let final Never #t13 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.[](let final Never #t14 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never n7 = let final Never #t15 = (let final Never #t16 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.call() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never n8 = let final Never #t17 = (let final Never #t18 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.runtimeType() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never n9 = let final Never #t19 = (let final Never #t20 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.toString in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    (let final Never #t21 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.runtimeType = #C1;
+    (let final Never #t22 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.toString = () → core::String => "";
+    Never v1 = let final Never #t23 = (let final Never #t24 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.toString() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never v2 = let final Never #t25 = (let final Never #t26 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.runtimeType in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never v3 = let final Never #t27 = (let final Never #t28 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.someGetter in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never v4 = let final Never #t29 = (let final Never #t30 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.someMethod() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never v5 = let final Never #t31 = (let final Never #t32 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.+(let final Never #t33 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never v6 = let final Never #t34 = (let final Never #t35 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.[](let final Never #t36 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never v7 = let final Never #t37 = (let final Never #t38 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.call() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never v8 = let final Never #t39 = (let final Never #t40 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.runtimeType() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    Never v9 = let final Never #t41 = (let final Never #t42 = x{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.toString in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  }
+}
+static method main() → dynamic {
+  self::test(null);
+}
+
+constants  {
+  #C1 = TypeLiteralConstant(core::Object*)
+}
diff --git a/pkg/front_end/testcases/nnbd/issue41349.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41349.dart.weak.modular.expect
new file mode 100644
index 0000000..16cf6c9
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41349.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method foo() → dynamic
+    return 23;
+}
+extension B on self::A? {
+  method foo = self::B|foo;
+  tearoff foo = self::B|get#foo;
+  method bar = self::B|bar;
+  tearoff bar = self::B|get#bar;
+}
+extension C on self::A {
+  method bar = self::C|bar;
+  tearoff bar = self::C|get#bar;
+}
+extension D on () →? core::int {
+  method call = self::D|call;
+  tearoff call = self::D|get#call;
+}
+static method B|foo(lowered final self::A? #this) → dynamic
+  return 42;
+static method B|get#foo(lowered final self::A? #this) → () → dynamic
+  return () → dynamic => self::B|foo(#this);
+static method B|bar(lowered final self::A? #this) → dynamic
+  return 87;
+static method B|get#bar(lowered final self::A? #this) → () → dynamic
+  return () → dynamic => self::B|bar(#this);
+static method C|bar(lowered final self::A #this) → dynamic
+  return 123;
+static method C|get#bar(lowered final self::A #this) → () → dynamic
+  return () → dynamic => self::C|bar(#this);
+static method D|call(lowered final () →? core::int #this) → core::int
+  return 76;
+static method D|get#call(lowered final () →? core::int #this) → () → core::int
+  return () → core::int => self::D|call(#this);
+static method main() → dynamic {
+  self::testA(new self::A::•());
+  self::testFunction(() → core::int => 53);
+}
+static method testA(self::A? a) → dynamic {
+  self::expect(23, let final self::A? #t1 = a in #t1 == null ?{dynamic} null : #t1{self::A}.{self::A::foo}(){() → dynamic});
+  self::expect(42, self::B|foo(a));
+  self::expect(123, let final self::A? #t2 = a in #t2 == null ?{dynamic} null : self::C|bar(#t2{self::A}));
+  self::expect(87, self::B|bar(a));
+}
+static method testFunction(() →? core::int f) → dynamic {
+  self::expect(53, let final () →? core::int #t3 = f in #t3 == null ?{core::int?} null : #t3{() → core::int}(){() → core::int});
+  self::expect(76, self::D|call(f));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/nnbd/issue41386.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41386.dart.weak.modular.expect
new file mode 100644
index 0000000..fbc0fe4
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41386.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue41386.dart:8:28: Error: The operator '%' isn't defined for the class 'Object?'.
+//  - 'Object' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '%' operator.
+//   print(predicate((v) => v % 2 == 1)(3));
+//                            ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method predicate<T extends core::Object? = dynamic>((self::predicate::T%) → core::bool fn) → (self::predicate::T%) → core::bool
+  return (self::predicate::T% val) → core::bool => fn(val){(self::predicate::T%) → core::bool};
+static method test() → void {
+  core::print(self::predicate<core::Object?>((core::Object? v) → core::bool => invalid-expression "pkg/front_end/testcases/nnbd/issue41386.dart:8:28: Error: The operator '%' isn't defined for the class 'Object?'.
+ - 'Object' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '%' operator.
+  print(predicate((v) => v % 2 == 1)(3));
+                           ^" in v{<unresolved>}.%(2) =={core::Object::==}{(core::Object) → core::bool} 1)(3){(core::Object?) → core::bool});
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/nnbd/issue41386b.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41386b.dart.weak.modular.expect
new file mode 100644
index 0000000..7223846
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41386b.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method test() → void {
+  core::Map<dynamic, dynamic> map = <dynamic, dynamic>{};
+  map.{core::Map::[]}(0){(core::Object?) → dynamic}{dynamic}.foo;
+  core::Iterable<core::String> elements = <core::String>[];
+  core::List<dynamic> list = core::List::from<dynamic>(elements);
+  core::List::from<dynamic>(elements).{core::Iterable::forEach}((dynamic element) → void => element{dynamic}.foo){((dynamic) → void) → void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue41415.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41415.dart.weak.modular.expect
new file mode 100644
index 0000000..818e367a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41415.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {}
+static method test<X extends Null, Y extends Never?, Z extends Never>() → dynamic {
+  (Null) → core::int f = (core::Object? x) → core::int => 1;
+  (Never) → core::int g = (core::Object? x) → core::int => 1;
+  (Never?) → core::int h = (core::Object? x) → core::int => 1;
+  (core::String) → core::int i = (core::String x) → core::int => 1;
+  (self::test::X%) → core::int j = (core::Object? x) → core::int => 1;
+  (self::test::Y%) → core::int k = (core::Object? x) → core::int => 1;
+  (self::test::Z) → core::int l = (core::Object? x) → core::int => 1;
+  (self::test::Z?) → core::int m = (core::Object? x) → core::int => 1;
+}
diff --git a/pkg/front_end/testcases/nnbd/issue41437a.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41437a.dart.weak.modular.expect
new file mode 100644
index 0000000..6b82704
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41437a.dart.weak.modular.expect
@@ -0,0 +1,94 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue41437a.dart:18:25: Error: A value of type 'Future<dynamic>' can't be returned from a function with return type 'Future<bool>'.
+//  - 'Future' is from 'dart:async'.
+// Future<bool> test5() => getFutureNull(); // error
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/issue41437a.dart:27:27: Error: A value of type 'Future<dynamic>' can't be returned from a function with return type 'Future<bool>'.
+//  - 'Future' is from 'dart:async'.
+//   Future<bool> test5() => getFutureNull(); // error
+//                           ^
+//
+// pkg/front_end/testcases/nnbd/issue41437a.dart:31:52: Error: A value of type 'Future<dynamic>' can't be assigned to a variable of type 'Future<bool>'.
+//  - 'Future' is from 'dart:async'.
+//   Future<bool> var1 = (() async => await getNull())(); // error
+//                                                    ^
+//
+// pkg/front_end/testcases/nnbd/issue41437a.dart:34:58: Error: A value of type 'Future<dynamic>' can't be assigned to a variable of type 'Future<bool>'.
+//  - 'Future' is from 'dart:async'.
+//   Future<bool> var4 = (() async => await getFutureNull())(); // error
+//                                                          ^
+//
+// pkg/front_end/testcases/nnbd/issue41437a.dart:35:46: Error: A value of type 'Future<dynamic>' can't be assigned to a variable of type 'Future<bool>'.
+//  - 'Future' is from 'dart:async'.
+//   Future<bool> var5 = (() => getFutureNull())(); // error
+//                                              ^
+//
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+static method getNull() → dynamic
+  return null;
+static method getFutureNull() → asy::Future<dynamic> async {
+  return null;
+}
+static method getFutureBool() → asy::Future<core::bool> async {
+  return true;
+}
+static method test1() → asy::Future<core::bool> async 
+  return await self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} FutureOr<core::bool>;
+static method test2() → asy::Future<core::bool>
+  return self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} asy::Future<core::bool>;
+static method test3() → core::bool
+  return self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool;
+static method test4() → asy::Future<core::bool> async 
+  return await self::getFutureNull() as{TypeError,ForDynamic,ForNonNullableByDefault} FutureOr<core::bool>;
+static method test5() → asy::Future<core::bool>
+  return invalid-expression "pkg/front_end/testcases/nnbd/issue41437a.dart:18:25: Error: A value of type 'Future<dynamic>' can't be returned from a function with return type 'Future<bool>'.
+ - 'Future' is from 'dart:async'.
+Future<bool> test5() => getFutureNull(); // error
+                        ^" in self::getFutureNull() as{TypeError,ForNonNullableByDefault} asy::Future<core::bool>;
+static method test6() → asy::Future<core::bool>
+  return self::getFutureBool();
+static method test7() → asy::Future<core::bool> async 
+  return self::getFutureBool();
+static method test() → dynamic async {
+  function test1() → asy::Future<core::bool> async 
+    return await self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} FutureOr<core::bool>;
+  function test2() → asy::Future<core::bool>
+    return self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} asy::Future<core::bool>;
+  function test3() → core::bool
+    return self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool;
+  function test4() → asy::Future<core::bool> async 
+    return await self::getFutureNull() as{TypeError,ForDynamic,ForNonNullableByDefault} FutureOr<core::bool>;
+  function test5() → asy::Future<core::bool>
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue41437a.dart:27:27: Error: A value of type 'Future<dynamic>' can't be returned from a function with return type 'Future<bool>'.
+ - 'Future' is from 'dart:async'.
+  Future<bool> test5() => getFutureNull(); // error
+                          ^" in self::getFutureNull() as{TypeError,ForNonNullableByDefault} asy::Future<core::bool>;
+  function test6() → asy::Future<core::bool>
+    return self::getFutureBool();
+  function test7() → asy::Future<core::bool> async 
+    return self::getFutureBool();
+  asy::Future<core::bool> var1 = invalid-expression "pkg/front_end/testcases/nnbd/issue41437a.dart:31:52: Error: A value of type 'Future<dynamic>' can't be assigned to a variable of type 'Future<bool>'.
+ - 'Future' is from 'dart:async'.
+  Future<bool> var1 = (() async => await getNull())(); // error
+                                                   ^" in (() → asy::Future<dynamic> async => await self::getNull())(){() → asy::Future<dynamic>} as{TypeError,ForNonNullableByDefault} asy::Future<core::bool>;
+  asy::Future<core::bool> var2 = (() → dynamic => self::getNull())(){() → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} asy::Future<core::bool>;
+  core::bool var3 = (() → dynamic => self::getNull())(){() → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool;
+  asy::Future<core::bool> var4 = invalid-expression "pkg/front_end/testcases/nnbd/issue41437a.dart:34:58: Error: A value of type 'Future<dynamic>' can't be assigned to a variable of type 'Future<bool>'.
+ - 'Future' is from 'dart:async'.
+  Future<bool> var4 = (() async => await getFutureNull())(); // error
+                                                         ^" in (() → asy::Future<dynamic> async => await self::getFutureNull())(){() → asy::Future<dynamic>} as{TypeError,ForNonNullableByDefault} asy::Future<core::bool>;
+  asy::Future<core::bool> var5 = invalid-expression "pkg/front_end/testcases/nnbd/issue41437a.dart:35:46: Error: A value of type 'Future<dynamic>' can't be assigned to a variable of type 'Future<bool>'.
+ - 'Future' is from 'dart:async'.
+  Future<bool> var5 = (() => getFutureNull())(); // error
+                                             ^" in (() → asy::Future<dynamic> => self::getFutureNull())(){() → asy::Future<dynamic>} as{TypeError,ForNonNullableByDefault} asy::Future<core::bool>;
+  asy::Future<core::bool> var6 = (() → asy::Future<core::bool> => self::getFutureBool())(){() → asy::Future<core::bool>};
+  asy::Future<core::bool> var7 = (() → asy::Future<core::bool> async => self::getFutureBool())(){() → asy::Future<core::bool>};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue41437b.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41437b.dart.weak.modular.expect
new file mode 100644
index 0000000..89bdcad
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41437b.dart.weak.modular.expect
@@ -0,0 +1,121 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue41437b.dart:21:10: Error: A value of type 'Iterable<dynamic>' can't be assigned to a variable of type 'Iterable<bool>'.
+//  - 'Iterable' is from 'dart:core'.
+//   yield* getIterableNull(); // error
+//          ^
+//
+// pkg/front_end/testcases/nnbd/issue41437b.dart:24:27: Error: A value of type 'Iterable<dynamic>' can't be returned from a function with return type 'Iterable<bool>'.
+//  - 'Iterable' is from 'dart:core'.
+// Iterable<bool> test5() => getIterableNull(); // error
+//                           ^
+//
+// pkg/front_end/testcases/nnbd/issue41437b.dart:38:12: Error: A value of type 'Iterable<dynamic>' can't be assigned to a variable of type 'Iterable<bool>'.
+//  - 'Iterable' is from 'dart:core'.
+//     yield* getIterableNull(); // error
+//            ^
+//
+// pkg/front_end/testcases/nnbd/issue41437b.dart:41:29: Error: A value of type 'Iterable<dynamic>' can't be returned from a function with return type 'Iterable<bool>'.
+//  - 'Iterable' is from 'dart:core'.
+//   Iterable<bool> test5() => getIterableNull(); // error
+//                             ^
+//
+// pkg/front_end/testcases/nnbd/issue41437b.dart:49:5: Error: A value of type 'Iterable<dynamic>' can't be assigned to a variable of type 'Iterable<bool>'.
+//  - 'Iterable' is from 'dart:core'.
+//   })(); // error
+//     ^
+//
+// pkg/front_end/testcases/nnbd/issue41437b.dart:54:5: Error: A value of type 'Iterable<dynamic>' can't be assigned to a variable of type 'Iterable<bool>'.
+//  - 'Iterable' is from 'dart:core'.
+//   })(); // error
+//     ^
+//
+// pkg/front_end/testcases/nnbd/issue41437b.dart:55:50: Error: A value of type 'Iterable<dynamic>' can't be assigned to a variable of type 'Iterable<bool>'.
+//  - 'Iterable' is from 'dart:core'.
+//   Iterable<bool> var5 = (() => getIterableNull())(); // error
+//                                                  ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method getNull() → dynamic
+  return null;
+static method getIterableNull() → core::Iterable<dynamic> sync* {
+  yield null;
+}
+static method getIterableBool() → core::Iterable<core::bool> sync* {
+  yield true;
+}
+static method test1() → core::Iterable<core::bool> sync* {
+  yield self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool;
+}
+static method test2() → core::Iterable<core::bool>
+  return self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<core::bool>;
+static method test3() → core::bool
+  return self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool;
+static method test4() → core::Iterable<core::bool> sync* {
+  yield* invalid-expression "pkg/front_end/testcases/nnbd/issue41437b.dart:21:10: Error: A value of type 'Iterable<dynamic>' can't be assigned to a variable of type 'Iterable<bool>'.
+ - 'Iterable' is from 'dart:core'.
+  yield* getIterableNull(); // error
+         ^" in self::getIterableNull() as{TypeError,ForNonNullableByDefault} core::Iterable<core::bool>;
+}
+static method test5() → core::Iterable<core::bool>
+  return invalid-expression "pkg/front_end/testcases/nnbd/issue41437b.dart:24:27: Error: A value of type 'Iterable<dynamic>' can't be returned from a function with return type 'Iterable<bool>'.
+ - 'Iterable' is from 'dart:core'.
+Iterable<bool> test5() => getIterableNull(); // error
+                          ^" in self::getIterableNull() as{TypeError,ForNonNullableByDefault} core::Iterable<core::bool>;
+static method test6() → core::Iterable<core::bool>
+  return self::getIterableBool();
+static method test7() → core::Iterable<core::bool> sync* {
+  yield* self::getIterableBool();
+}
+static method test() → dynamic async {
+  function test1() → core::Iterable<core::bool> sync* {
+    yield self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool;
+  }
+  function test2() → core::Iterable<core::bool>
+    return self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<core::bool>;
+  function test3() → core::bool
+    return self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool;
+  function test4() → core::Iterable<core::bool> sync* {
+    yield* invalid-expression "pkg/front_end/testcases/nnbd/issue41437b.dart:38:12: Error: A value of type 'Iterable<dynamic>' can't be assigned to a variable of type 'Iterable<bool>'.
+ - 'Iterable' is from 'dart:core'.
+    yield* getIterableNull(); // error
+           ^" in self::getIterableNull() as{TypeError,ForNonNullableByDefault} core::Iterable<core::bool>;
+  }
+  function test5() → core::Iterable<core::bool>
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue41437b.dart:41:29: Error: A value of type 'Iterable<dynamic>' can't be returned from a function with return type 'Iterable<bool>'.
+ - 'Iterable' is from 'dart:core'.
+  Iterable<bool> test5() => getIterableNull(); // error
+                            ^" in self::getIterableNull() as{TypeError,ForNonNullableByDefault} core::Iterable<core::bool>;
+  function test6() → core::Iterable<core::bool>
+    return self::getIterableBool();
+  function test7() → core::Iterable<core::bool> sync* {
+    yield* self::getIterableBool();
+  }
+  core::Iterable<core::bool> var1 = invalid-expression "pkg/front_end/testcases/nnbd/issue41437b.dart:49:5: Error: A value of type 'Iterable<dynamic>' can't be assigned to a variable of type 'Iterable<bool>'.
+ - 'Iterable' is from 'dart:core'.
+  })(); // error
+    ^" in (() → core::Iterable<dynamic> sync* {
+    yield self::getNull();
+  })(){() → core::Iterable<dynamic>} as{TypeError,ForNonNullableByDefault} core::Iterable<core::bool>;
+  core::Iterable<core::bool> var2 = (() → dynamic => self::getNull())(){() → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<core::bool>;
+  core::bool var3 = (() → dynamic => self::getNull())(){() → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool;
+  core::Iterable<core::bool> var4 = invalid-expression "pkg/front_end/testcases/nnbd/issue41437b.dart:54:5: Error: A value of type 'Iterable<dynamic>' can't be assigned to a variable of type 'Iterable<bool>'.
+ - 'Iterable' is from 'dart:core'.
+  })(); // error
+    ^" in (() → core::Iterable<dynamic> sync* {
+    yield* self::getIterableNull();
+  })(){() → core::Iterable<dynamic>} as{TypeError,ForNonNullableByDefault} core::Iterable<core::bool>;
+  core::Iterable<core::bool> var5 = invalid-expression "pkg/front_end/testcases/nnbd/issue41437b.dart:55:50: Error: A value of type 'Iterable<dynamic>' can't be assigned to a variable of type 'Iterable<bool>'.
+ - 'Iterable' is from 'dart:core'.
+  Iterable<bool> var5 = (() => getIterableNull())(); // error
+                                                 ^" in (() → core::Iterable<dynamic> => self::getIterableNull())(){() → core::Iterable<dynamic>} as{TypeError,ForNonNullableByDefault} core::Iterable<core::bool>;
+  core::Iterable<core::bool> var6 = (() → core::Iterable<core::bool> => self::getIterableBool())(){() → core::Iterable<core::bool>};
+  core::Iterable<core::bool> var7 = (() → core::Iterable<core::bool> sync* {
+    yield* self::getIterableBool();
+  })(){() → core::Iterable<core::bool>};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue41437c.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41437c.dart.weak.modular.expect
new file mode 100644
index 0000000..54bbc93
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41437c.dart.weak.modular.expect
@@ -0,0 +1,122 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue41437c.dart:21:10: Error: A value of type 'Stream<dynamic>' can't be assigned to a variable of type 'Stream<bool>'.
+//  - 'Stream' is from 'dart:async'.
+//   yield* getStreamNull(); // error
+//          ^
+//
+// pkg/front_end/testcases/nnbd/issue41437c.dart:24:25: Error: A value of type 'Stream<dynamic>' can't be returned from a function with return type 'Stream<bool>'.
+//  - 'Stream' is from 'dart:async'.
+// Stream<bool> test5() => getStreamNull(); // error
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/issue41437c.dart:38:12: Error: A value of type 'Stream<dynamic>' can't be assigned to a variable of type 'Stream<bool>'.
+//  - 'Stream' is from 'dart:async'.
+//     yield* getStreamNull(); // error
+//            ^
+//
+// pkg/front_end/testcases/nnbd/issue41437c.dart:41:27: Error: A value of type 'Stream<dynamic>' can't be returned from a function with return type 'Stream<bool>'.
+//  - 'Stream' is from 'dart:async'.
+//   Stream<bool> test5() => getStreamNull(); // error
+//                           ^
+//
+// pkg/front_end/testcases/nnbd/issue41437c.dart:49:5: Error: A value of type 'Stream<dynamic>' can't be assigned to a variable of type 'Stream<bool>'.
+//  - 'Stream' is from 'dart:async'.
+//   })(); // error
+//     ^
+//
+// pkg/front_end/testcases/nnbd/issue41437c.dart:54:5: Error: A value of type 'Stream<dynamic>' can't be assigned to a variable of type 'Stream<bool>'.
+//  - 'Stream' is from 'dart:async'.
+//   })(); // error
+//     ^
+//
+// pkg/front_end/testcases/nnbd/issue41437c.dart:55:46: Error: A value of type 'Stream<dynamic>' can't be assigned to a variable of type 'Stream<bool>'.
+//  - 'Stream' is from 'dart:async'.
+//   Stream<bool> var5 = (() => getStreamNull())(); // error
+//                                              ^
+//
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+static method getNull() → dynamic
+  return null;
+static method getStreamNull() → asy::Stream<dynamic> async* {
+  yield null;
+}
+static method getStreamBool() → asy::Stream<core::bool> async* {
+  yield true;
+}
+static method test1() → asy::Stream<core::bool> async* {
+  yield self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool;
+}
+static method test2() → asy::Stream<core::bool>
+  return self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} asy::Stream<core::bool>;
+static method test3() → core::bool
+  return self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool;
+static method test4() → asy::Stream<core::bool> async* {
+  yield* invalid-expression "pkg/front_end/testcases/nnbd/issue41437c.dart:21:10: Error: A value of type 'Stream<dynamic>' can't be assigned to a variable of type 'Stream<bool>'.
+ - 'Stream' is from 'dart:async'.
+  yield* getStreamNull(); // error
+         ^" in self::getStreamNull() as{TypeError,ForNonNullableByDefault} asy::Stream<core::bool>;
+}
+static method test5() → asy::Stream<core::bool>
+  return invalid-expression "pkg/front_end/testcases/nnbd/issue41437c.dart:24:25: Error: A value of type 'Stream<dynamic>' can't be returned from a function with return type 'Stream<bool>'.
+ - 'Stream' is from 'dart:async'.
+Stream<bool> test5() => getStreamNull(); // error
+                        ^" in self::getStreamNull() as{TypeError,ForNonNullableByDefault} asy::Stream<core::bool>;
+static method test6() → asy::Stream<core::bool>
+  return self::getStreamBool();
+static method test7() → asy::Stream<core::bool> async* {
+  yield* self::getStreamBool();
+}
+static method test() → dynamic async {
+  function test1() → asy::Stream<core::bool> async* {
+    yield self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool;
+  }
+  function test2() → asy::Stream<core::bool>
+    return self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} asy::Stream<core::bool>;
+  function test3() → core::bool
+    return self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool;
+  function test4() → asy::Stream<core::bool> async* {
+    yield* invalid-expression "pkg/front_end/testcases/nnbd/issue41437c.dart:38:12: Error: A value of type 'Stream<dynamic>' can't be assigned to a variable of type 'Stream<bool>'.
+ - 'Stream' is from 'dart:async'.
+    yield* getStreamNull(); // error
+           ^" in self::getStreamNull() as{TypeError,ForNonNullableByDefault} asy::Stream<core::bool>;
+  }
+  function test5() → asy::Stream<core::bool>
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue41437c.dart:41:27: Error: A value of type 'Stream<dynamic>' can't be returned from a function with return type 'Stream<bool>'.
+ - 'Stream' is from 'dart:async'.
+  Stream<bool> test5() => getStreamNull(); // error
+                          ^" in self::getStreamNull() as{TypeError,ForNonNullableByDefault} asy::Stream<core::bool>;
+  function test6() → asy::Stream<core::bool>
+    return self::getStreamBool();
+  function test7() → asy::Stream<core::bool> async* {
+    yield* self::getStreamBool();
+  }
+  asy::Stream<core::bool> var1 = invalid-expression "pkg/front_end/testcases/nnbd/issue41437c.dart:49:5: Error: A value of type 'Stream<dynamic>' can't be assigned to a variable of type 'Stream<bool>'.
+ - 'Stream' is from 'dart:async'.
+  })(); // error
+    ^" in (() → asy::Stream<dynamic> async* {
+    yield self::getNull();
+  })(){() → asy::Stream<dynamic>} as{TypeError,ForNonNullableByDefault} asy::Stream<core::bool>;
+  asy::Stream<core::bool> var2 = (() → dynamic => self::getNull())(){() → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} asy::Stream<core::bool>;
+  core::bool var3 = (() → dynamic => self::getNull())(){() → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool;
+  asy::Stream<core::bool> var4 = invalid-expression "pkg/front_end/testcases/nnbd/issue41437c.dart:54:5: Error: A value of type 'Stream<dynamic>' can't be assigned to a variable of type 'Stream<bool>'.
+ - 'Stream' is from 'dart:async'.
+  })(); // error
+    ^" in (() → asy::Stream<dynamic> async* {
+    yield* self::getStreamNull();
+  })(){() → asy::Stream<dynamic>} as{TypeError,ForNonNullableByDefault} asy::Stream<core::bool>;
+  asy::Stream<core::bool> var5 = invalid-expression "pkg/front_end/testcases/nnbd/issue41437c.dart:55:46: Error: A value of type 'Stream<dynamic>' can't be assigned to a variable of type 'Stream<bool>'.
+ - 'Stream' is from 'dart:async'.
+  Stream<bool> var5 = (() => getStreamNull())(); // error
+                                             ^" in (() → asy::Stream<dynamic> => self::getStreamNull())(){() → asy::Stream<dynamic>} as{TypeError,ForNonNullableByDefault} asy::Stream<core::bool>;
+  asy::Stream<core::bool> var6 = (() → asy::Stream<core::bool> => self::getStreamBool())(){() → asy::Stream<core::bool>};
+  asy::Stream<core::bool> var7 = (() → asy::Stream<core::bool> async* {
+    yield* self::getStreamBool();
+  })(){() → asy::Stream<core::bool>};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue41495.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41495.dart.weak.modular.expect
new file mode 100644
index 0000000..f5982c7
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41495.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue41495.dart:14:6: Error: Property 'c1' cannot be accessed on 'A?' because it is potentially null.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue41495.dart'.
+// Try accessing using ?. instead.
+//   a1.c1;
+//      ^^
+//
+// pkg/front_end/testcases/nnbd/issue41495.dart:15:6: Error: Property 'test' cannot be accessed on 'A?' because it is potentially null.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue41495.dart'.
+// Try accessing using ?. instead.
+//   a1.test;
+//      ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int c1 = 1;
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method test() → core::int
+    return 2;
+}
+static method main() → dynamic {}
+static method errors() → dynamic {
+  self::A? a1 = new self::A::•() as{ForNonNullableByDefault} self::A?;
+  invalid-expression "pkg/front_end/testcases/nnbd/issue41495.dart:14:6: Error: Property 'c1' cannot be accessed on 'A?' because it is potentially null.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/issue41495.dart'.
+Try accessing using ?. instead.
+  a1.c1;
+     ^^" in a1.{self::A::c1}{<nullable>}.{core::int};
+  invalid-expression "pkg/front_end/testcases/nnbd/issue41495.dart:15:6: Error: Property 'test' cannot be accessed on 'A?' because it is potentially null.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/issue41495.dart'.
+Try accessing using ?. instead.
+  a1.test;
+     ^^^^" in a1.{self::A::test}{<nullable>}.{() → core::int};
+}
diff --git a/pkg/front_end/testcases/nnbd/issue41520.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41520.dart.weak.modular.expect
new file mode 100644
index 0000000..c66c505
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41520.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue41520.dart:7:11: Error: The method 'notAMethodOnObject' isn't defined for the class 'Object'.
+//  - 'Object' is from 'dart:core'.
+// Try correcting the name to the name of an existing method, or defining a method named 'notAMethodOnObject'.
+//     error.notAMethodOnObject();
+//           ^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue41520.dart:12:11: Error: The method 'notAMethodOnObject' isn't defined for the class 'Object'.
+//  - 'Object' is from 'dart:core'.
+// Try correcting the name to the name of an existing method, or defining a method named 'notAMethodOnObject'.
+//     error.notAMethodOnObject();
+//           ^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue41520.dart:13:16: Error: The method 'notAMethodOnStackTrace' isn't defined for the class 'StackTrace'.
+//  - 'StackTrace' is from 'dart:core'.
+// Try correcting the name to the name of an existing method, or defining a method named 'notAMethodOnStackTrace'.
+//     stackTrace.notAMethodOnStackTrace();
+//                ^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method errors() → void {
+  try {
+  }
+  on core::Object catch(final core::Object error) {
+    invalid-expression "pkg/front_end/testcases/nnbd/issue41520.dart:7:11: Error: The method 'notAMethodOnObject' isn't defined for the class 'Object'.
+ - 'Object' is from 'dart:core'.
+Try correcting the name to the name of an existing method, or defining a method named 'notAMethodOnObject'.
+    error.notAMethodOnObject();
+          ^^^^^^^^^^^^^^^^^^" in error{<unresolved>}.notAMethodOnObject();
+    self::_takesObject(error);
+  }
+  try {
+  }
+  on core::Object catch(final core::Object error, final core::StackTrace stackTrace) {
+    invalid-expression "pkg/front_end/testcases/nnbd/issue41520.dart:12:11: Error: The method 'notAMethodOnObject' isn't defined for the class 'Object'.
+ - 'Object' is from 'dart:core'.
+Try correcting the name to the name of an existing method, or defining a method named 'notAMethodOnObject'.
+    error.notAMethodOnObject();
+          ^^^^^^^^^^^^^^^^^^" in error{<unresolved>}.notAMethodOnObject();
+    invalid-expression "pkg/front_end/testcases/nnbd/issue41520.dart:13:16: Error: The method 'notAMethodOnStackTrace' isn't defined for the class 'StackTrace'.
+ - 'StackTrace' is from 'dart:core'.
+Try correcting the name to the name of an existing method, or defining a method named 'notAMethodOnStackTrace'.
+    stackTrace.notAMethodOnStackTrace();
+               ^^^^^^^^^^^^^^^^^^^^^^" in stackTrace{<unresolved>}.notAMethodOnStackTrace();
+    self::_takesObject(error);
+    self::_takesStackTrace(stackTrace);
+  }
+}
+static method _takesObject(core::Object o) → void {}
+static method _takesStackTrace(core::StackTrace o) → void {}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/nnbd/issue41602.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41602.dart.weak.modular.expect
new file mode 100644
index 0000000..d7d296d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41602.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue41602.dart:12:9: Error: This expression has type 'void' and can't be used.
+//   await returnVoid(); // error
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue41602.dart:13:9: Error: This expression has type 'void' and can't be used.
+//   await returnVoidAsync(); // error
+//         ^
+//
+import self as self;
+import "dart:async" as asy;
+
+static method returnFutureOfVoid() → asy::Future<void> async {}
+static method returnVoid() → void {}
+static method returnVoidAsync() → void async {}
+static method test() → dynamic async {
+  await self::returnVoid();
+  await self::returnVoidAsync();
+}
+static method main() → dynamic async {
+  await self::returnFutureOfVoid();
+}
diff --git a/pkg/front_end/testcases/nnbd/issue41657.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41657.dart.weak.modular.expect
new file mode 100644
index 0000000..d4bfe7f
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41657.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static final field core::bool isLegacySubtyping1a = <Null>[] is{ForNonNullableByDefault} core::List<core::int>;
+static const field core::bool isLegacySubtyping1b = #C1;
+static final field core::bool isLegacySubtyping2a = <core::int?>[] is{ForNonNullableByDefault} core::List<core::int>;
+static const field core::bool isLegacySubtyping2b = #C1;
+static const field core::List<core::int> assertLegacySubtyping1 = #C2;
+static const field core::List<core::int> assertLegacySubtyping2 = #C3;
+static method main() → void {
+  self::expect(self::isLegacySubtyping1a, #C1);
+  self::expect(self::isLegacySubtyping2a, #C1);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = true
+  #C2 = <Null>[]
+  #C3 = <core::int?>[]
+}
diff --git a/pkg/front_end/testcases/nnbd/issue41697.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41697.dart.weak.modular.expect
new file mode 100644
index 0000000..d7f0e7d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41697.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue41697.dart:33:14: Error: Operator '+' cannot be called on 'S' because it is potentially null.
+//     return s + 1; // error
+//              ^
+//
+// pkg/front_end/testcases/nnbd/issue41697.dart:36:22: Error: Operator '+' cannot be called on 'num?' because it is potentially null.
+//     return (await t) + 1; // error
+//                      ^
+//
+// pkg/front_end/testcases/nnbd/issue41697.dart:40:33: Error: Operator '+' cannot be called on 'S' because it is potentially null.
+// test3<S extends num?>(S s) => s + 1; // error
+//                                 ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+typedef G<invariant T extends core::Object? = dynamic> = <S extends T% = dynamic>(S%) → dynamic;
+typedef H<invariant T extends core::Object? = dynamic> = <S extends FutureOr<T%> = dynamic>(S%, FutureOr<T%>) → dynamic;
+class C<T extends core::Object? = dynamic> extends core::Object {
+  covariant-by-class field <S extends self::C::T% = dynamic>(S%) → dynamic field1;
+  covariant-by-class field <S extends FutureOr<self::C::T%> = dynamic>(S%, FutureOr<self::C::T%>) → dynamic field2;
+  constructor •(<S extends self::C::T% = dynamic>(S%) → dynamic field1, <S extends FutureOr<self::C::T%> = dynamic>(S%, FutureOr<self::C::T%>) → dynamic field2) → self::C<self::C::T%>
+    : self::C::field1 = field1, self::C::field2 = field2, super core::Object::•()
+    ;
+}
+static method test1(self::C<core::num> c) → dynamic {
+  <S extends core::num>(S) → core::num f1 = c.{self::C::field1} = <S extends core::num>(S s) → core::num {
+    return s.{core::num::+}(1){(core::num) → core::num};
+  };
+  <S extends FutureOr<core::num>>(S, FutureOr<core::num>) → asy::Future<core::num> f2 = c.{self::C::field2} = <S extends FutureOr<core::num>>(S s, FutureOr<core::num>t) → asy::Future<core::num> async {
+    return (await t).{core::num::+}(1){(core::num) → core::num};
+  };
+}
+static method test2(self::C<core::num?> c) → dynamic {
+  <S extends core::num?>(S%) → core::num f1 = c.{self::C::field1} = <S extends core::num?>(S% s) → core::num {
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue41697.dart:33:14: Error: Operator '+' cannot be called on 'S' because it is potentially null.
+    return s + 1; // error
+             ^" in s.{core::num::+}(1){(core::num) → core::num};
+  };
+  <S extends FutureOr<core::num?>>(S%, FutureOr<core::num?>) → asy::Future<core::num> f2 = c.{self::C::field2} = <S extends FutureOr<core::num?>>(S% s, FutureOr<core::num?>t) → asy::Future<core::num> async {
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue41697.dart:36:22: Error: Operator '+' cannot be called on 'num?' because it is potentially null.
+    return (await t) + 1; // error
+                     ^" in (await t).{core::num::+}(1){(core::num) → core::num};
+  };
+}
+static method test3<S extends core::num?>(self::test3::S% s) → dynamic
+  return invalid-expression "pkg/front_end/testcases/nnbd/issue41697.dart:40:33: Error: Operator '+' cannot be called on 'S' because it is potentially null.
+test3<S extends num?>(S s) => s + 1; // error
+                                ^" in s.{core::num::+}(1){(core::num) → core::num};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue41697b.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41697b.dart.weak.modular.expect
new file mode 100644
index 0000000..e45354a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41697b.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue41697b.dart:10:13: Error: Operator '+' cannot be called on 'S' because it is potentially null.
+//   var t = s + 1; // error
+//             ^
+//
+// pkg/front_end/testcases/nnbd/issue41697b.dart:18:13: Error: Operator '+' cannot be called on 'S' because it is potentially null.
+//   var t = s + 1; // error
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test1<S extends core::num>(self::test1::S s) → dynamic {
+  core::num t = s.{core::num::+}(1){(core::num) → core::num};
+}
+static method test2<S extends core::num?>(self::test2::S% s) → dynamic {
+  core::num t = invalid-expression "pkg/front_end/testcases/nnbd/issue41697b.dart:10:13: Error: Operator '+' cannot be called on 'S' because it is potentially null.
+  var t = s + 1; // error
+            ^" in s.{core::num::+}(1){(core::num) → core::num};
+}
+static method test3<S extends core::int>(self::test3::S s) → dynamic {
+  core::int t = s.{core::num::+}(1){(core::num) → core::int};
+}
+static method test4<S extends core::int?>(self::test4::S% s) → dynamic {
+  core::num t = invalid-expression "pkg/front_end/testcases/nnbd/issue41697b.dart:18:13: Error: Operator '+' cannot be called on 'S' because it is potentially null.
+  var t = s + 1; // error
+            ^" in s.{core::num::+}(1){(core::num) → core::num};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue41700a.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41700a.dart.weak.modular.expect
new file mode 100644
index 0000000..25b0480
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41700a.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue41700a.dart:7:5: Error: The method 'foo' isn't defined for the class 'Null'.
+// Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+//   x.foo();
+//     ^^^
+//
+// pkg/front_end/testcases/nnbd/issue41700a.dart:9:5: Error: The method 'foo' isn't defined for the class 'Null'.
+// Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+//   y.foo();
+//     ^^^
+//
+import self as self;
+
+static method test() → dynamic {
+  Null x = null;
+  invalid-expression "pkg/front_end/testcases/nnbd/issue41700a.dart:7:5: Error: The method 'foo' isn't defined for the class 'Null'.
+Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+  x.foo();
+    ^^^" in x{<unresolved>}.foo();
+  Null y = null;
+  invalid-expression "pkg/front_end/testcases/nnbd/issue41700a.dart:9:5: Error: The method 'foo' isn't defined for the class 'Null'.
+Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+  y.foo();
+    ^^^" in y{<unresolved>}.foo();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue41700b.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41700b.dart.weak.modular.expect
new file mode 100644
index 0000000..bf9a0db
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41700b.dart.weak.modular.expect
@@ -0,0 +1,47 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue41700b.dart:8:12: Error: The value 'null' can't be assigned to a variable of type 'Null' because 'Null' is not nullable.
+//  - 'Null' is from 'pkg/front_end/testcases/nnbd/issue41700b.dart'.
+//   Null x = null;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/issue41700b.dart:9:5: Error: The method 'foo' isn't defined for the class 'Null'.
+//  - 'Null' is from 'pkg/front_end/testcases/nnbd/issue41700b.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+//   x.foo();
+//     ^^^
+//
+// pkg/front_end/testcases/nnbd/issue41700b.dart:11:5: Error: The method 'foo' isn't defined for the class 'Null?'.
+//  - 'Null' is from 'pkg/front_end/testcases/nnbd/issue41700b.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+//   y.foo();
+//     ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Null extends core::Object {
+  synthetic constructor •() → self::Null
+    : super core::Object::•()
+    ;
+}
+static method test() → dynamic {
+  self::Null x = invalid-expression "pkg/front_end/testcases/nnbd/issue41700b.dart:8:12: Error: The value 'null' can't be assigned to a variable of type 'Null' because 'Null' is not nullable.
+ - 'Null' is from 'pkg/front_end/testcases/nnbd/issue41700b.dart'.
+  Null x = null;
+           ^" in null as{TypeError,ForNonNullableByDefault} self::Null;
+  invalid-expression "pkg/front_end/testcases/nnbd/issue41700b.dart:9:5: Error: The method 'foo' isn't defined for the class 'Null'.
+ - 'Null' is from 'pkg/front_end/testcases/nnbd/issue41700b.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+  x.foo();
+    ^^^" in x{<unresolved>}.foo();
+  self::Null? y = null;
+  invalid-expression "pkg/front_end/testcases/nnbd/issue41700b.dart:11:5: Error: The method 'foo' isn't defined for the class 'Null?'.
+ - 'Null' is from 'pkg/front_end/testcases/nnbd/issue41700b.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+  y.foo();
+    ^^^" in y{<unresolved>}.foo();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue41952.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue41952.dart.weak.modular.expect
new file mode 100644
index 0000000..3952efc
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue41952.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method i1<R extends core::Object? = dynamic>() → <S2 extends self::i1::R? = dynamic>() → void
+  return <S2 extends self::i1::R?>() → void {};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42089.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42089.dart.weak.modular.expect
new file mode 100644
index 0000000..1c01411
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42089.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue42089.dart:7:16: Error: A value of type 'X?' can't be assigned to a variable of type 'Object' because 'X?' is nullable and 'Object' isn't.
+//  - 'Object' is from 'dart:core'.
+//     Object o = x;
+//                ^
+//
+// pkg/front_end/testcases/nnbd/issue42089.dart:8:9: Error: A value of type 'X?' can't be assigned to a variable of type 'Object' because 'X?' is nullable and 'Object' isn't.
+//  - 'Object' is from 'dart:core'.
+//     o = x;
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test<X extends core::Object? = dynamic>(self::test::X? x) → dynamic {
+  if(x is{ForNonNullableByDefault} core::String?) {
+    core::Object o = invalid-expression "pkg/front_end/testcases/nnbd/issue42089.dart:7:16: Error: A value of type 'X?' can't be assigned to a variable of type 'Object' because 'X?' is nullable and 'Object' isn't.
+ - 'Object' is from 'dart:core'.
+    Object o = x;
+               ^" in x{self::test::X? & core::String? /* '?' & '?' = '?' */} as{TypeError,ForNonNullableByDefault} core::Object;
+    o = invalid-expression "pkg/front_end/testcases/nnbd/issue42089.dart:8:9: Error: A value of type 'X?' can't be assigned to a variable of type 'Object' because 'X?' is nullable and 'Object' isn't.
+ - 'Object' is from 'dart:core'.
+    o = x;
+        ^" in x{self::test::X? & core::String? /* '?' & '?' = '?' */} as{TypeError,ForNonNullableByDefault} core::Object;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42143.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42143.dart.weak.modular.expect
new file mode 100644
index 0000000..dd9388c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42143.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+
+import "dart:async";
+
+static method h1<T extends FutureOr<self::h1::T?>? = FutureOr<dynamic>?>(self::h1::T? t) → void {}
+static method h2<S extends FutureOr<self::h2::S?> = FutureOr<dynamic>>(self::h2::S? s) → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42199.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42199.dart.weak.modular.expect
new file mode 100644
index 0000000..3ae4f33
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42199.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  abstract operator ==(dynamic other) → core::bool;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42362.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42362.dart.weak.modular.expect
new file mode 100644
index 0000000..b233a23
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42362.dart.weak.modular.expect
@@ -0,0 +1,233 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:45:16: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   method3([int i]) {} // error
+//                ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:47:16: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   method4({int i}) {} // error
+//                ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:8:24: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   A.constructor1([this.i]); // error
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:10:24: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   A.constructor2({this.i}); // error
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:12:23: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   A.constructor3([int i]) // error
+//                       ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:15:23: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   A.constructor4({int i}) // error
+//                       ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:41:27: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   factory A.factory8([int i]) => new A.constructor3(); // error
+//                           ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:43:27: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   factory A.factory9({int i}) => new A.constructor4(); // error
+//                           ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:106:12: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   method3([i]) {} // error
+//            ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:108:12: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   method4({i}) {} // error
+//            ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:77:24: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   C.constructor1([this.i]); // error
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:79:24: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   C.constructor2({this.i}); // error
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:81:23: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   C.constructor3([int i]) : this.i = i; // error
+//                       ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:83:23: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   C.constructor4({int i}) : this.i = i; // error
+//                       ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:102:27: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   factory C.factory8([int i]) => new C.constructor3(); // error
+//                           ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:104:27: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   factory C.factory9({int i}) => new C.constructor4(); // error
+//                           ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:19:18: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+//       : this.i = i; // error
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:22:18: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+//       : this.i = i; // error
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:85:39: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+//   C.constructor5([int? i]) : this.i = i; // error
+//                                       ^
+//
+// pkg/front_end/testcases/nnbd/issue42362.dart:87:39: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+//   C.constructor6({int? i}) : this.i = i; // error
+//                                       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  final field core::int i;
+  static final field dynamic _redirecting# = <dynamic>[#C1, #C2, #C3, #C4, #C5]/*isLegacy*/;
+  constructor constructor1([core::int i = #C6]) → self::A
+    : self::A::i = i, super core::Object::•()
+    ;
+  constructor constructor2({core::int i = #C6}) → self::A
+    : self::A::i = i, super core::Object::•()
+    ;
+  constructor constructor3([core::int i = #C6]) → self::A
+    : self::A::i = i, super core::Object::•()
+    ;
+  constructor constructor4({core::int i = #C6}) → self::A
+    : self::A::i = i, super core::Object::•()
+    ;
+  constructor constructor5([core::int? i = #C6]) → self::A
+    : self::A::i = invalid-expression "pkg/front_end/testcases/nnbd/issue42362.dart:19:18: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+      : this.i = i; // error
+                 ^" in i as{TypeError,ForNonNullableByDefault} core::int, super core::Object::•()
+    ;
+  constructor constructor6({core::int? i = #C6}) → self::A
+    : self::A::i = invalid-expression "pkg/front_end/testcases/nnbd/issue42362.dart:22:18: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+      : this.i = i; // error
+                 ^" in i as{TypeError,ForNonNullableByDefault} core::int, super core::Object::•()
+    ;
+  constructor constructor7({required core::int i = #C6}) → self::A
+    : self::A::i = i, super core::Object::•()
+    ;
+  external constructor constructor8([core::int i = #C6]) → self::A
+    : super core::Object::•()
+    ;
+  external constructor constructor9({core::int i = #C6}) → self::A
+    : super core::Object::•()
+    ;
+  static factory factory3([core::int i = #C6]) → self::A
+    return new self::A::constructor3(i);
+  static factory factory4({core::int i = #C6}) → self::A
+    return new self::A::constructor4(i: i);
+  static factory factory5([core::int? i = #C6]) → self::A
+    return new self::A::constructor5(i);
+  static factory factory6({core::int? i = #C6}) → self::A
+    return new self::A::constructor6(i: i);
+  static factory factory7({required core::int i = #C6}) → self::A
+    return new self::A::constructor7(i: i);
+  static factory factory8([core::int i = #C6]) → self::A
+    return new self::A::constructor3();
+  static factory factory9({core::int i = #C6}) → self::A
+    return new self::A::constructor4();
+  method method3([core::int i = #C6]) → dynamic {}
+  method method4({core::int i = #C6}) → dynamic {}
+  method method5([core::int? i = #C6]) → dynamic {}
+  method method6({core::int? i = #C6}) → dynamic {}
+  method method7({required core::int i = #C6}) → dynamic {}
+  external method method8([core::int i = #C6]) → dynamic;
+  external method method9({core::int i = #C6}) → dynamic;
+}
+abstract class B extends core::Object {
+  field core::int i = 42;
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+  abstract method method3([core::int i = #C6]) → dynamic;
+  abstract method method4({core::int i = #C6}) → dynamic;
+  abstract method method5([core::int? i = #C6]) → dynamic;
+  abstract method method6({core::int? i = #C6}) → dynamic;
+  abstract method method7({required core::int i = #C6}) → dynamic;
+}
+class C extends core::Object implements self::B {
+  field core::int i;
+  static final field dynamic _redirecting# = <dynamic>[#C7, #C8, #C9, #C10, #C11]/*isLegacy*/;
+  constructor constructor1([core::int i = #C6]) → self::C
+    : self::C::i = i, super core::Object::•()
+    ;
+  constructor constructor2({core::int i = #C6}) → self::C
+    : self::C::i = i, super core::Object::•()
+    ;
+  constructor constructor3([core::int i = #C6]) → self::C
+    : self::C::i = i, super core::Object::•()
+    ;
+  constructor constructor4({core::int i = #C6}) → self::C
+    : self::C::i = i, super core::Object::•()
+    ;
+  constructor constructor5([core::int? i = #C6]) → self::C
+    : self::C::i = invalid-expression "pkg/front_end/testcases/nnbd/issue42362.dart:85:39: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+  C.constructor5([int? i]) : this.i = i; // error
+                                      ^" in i as{TypeError,ForNonNullableByDefault} core::int, super core::Object::•()
+    ;
+  constructor constructor6({core::int? i = #C6}) → self::C
+    : self::C::i = invalid-expression "pkg/front_end/testcases/nnbd/issue42362.dart:87:39: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+  C.constructor6({int? i}) : this.i = i; // error
+                                      ^" in i as{TypeError,ForNonNullableByDefault} core::int, super core::Object::•()
+    ;
+  constructor constructor7({required core::int i = #C6}) → self::C
+    : self::C::i = i, super core::Object::•()
+    ;
+  static factory factory3([core::int i = #C6]) → self::C
+    return new self::C::constructor3(i);
+  static factory factory4({core::int i = #C6}) → self::C
+    return new self::C::constructor4(i: i);
+  static factory factory5([core::int? i = #C6]) → self::C
+    return new self::C::constructor5(i);
+  static factory factory6({core::int? i = #C6}) → self::C
+    return new self::C::constructor6(i: i);
+  static factory factory7({required core::int i = #C6}) → self::C
+    return new self::C::constructor7(i: i);
+  static factory factory8([core::int i = #C6]) → self::C
+    return new self::C::constructor3();
+  static factory factory9({core::int i = #C6}) → self::C
+    return new self::C::constructor4();
+  method method3([core::int i = #C6]) → dynamic {}
+  method method4({core::int i = #C6}) → dynamic {}
+  method method5([core::int? i = #C6]) → dynamic {}
+  method method6({core::int? i = #C6}) → dynamic {}
+  method method7({required core::int i = #C6}) → dynamic {}
+}
+static method main() → void {}
+
+constants  {
+  #C1 = constructor-tearoff self::A::factory3
+  #C2 = constructor-tearoff self::A::factory4
+  #C3 = constructor-tearoff self::A::factory5
+  #C4 = constructor-tearoff self::A::factory6
+  #C5 = constructor-tearoff self::A::factory7
+  #C6 = null
+  #C7 = constructor-tearoff self::C::factory3
+  #C8 = constructor-tearoff self::C::factory4
+  #C9 = constructor-tearoff self::C::factory5
+  #C10 = constructor-tearoff self::C::factory6
+  #C11 = constructor-tearoff self::C::factory7
+}
diff --git a/pkg/front_end/testcases/nnbd/issue42429.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42429.dart.weak.modular.expect
new file mode 100644
index 0000000..717c859
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42429.dart.weak.modular.expect
@@ -0,0 +1,259 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:13:13: Error: Type argument 'Object' doesn't conform to the bound 'num' of the type variable 'T' on 'A'.
+//  - 'Object' is from 'dart:core'.
+// Try changing type arguments so that they conform to the bounds.
+//   A<Object> aObject; // Error.
+//             ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<T extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:14:11: Error: Type argument 'num?' doesn't conform to the bound 'num' of the type variable 'T' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+//   A<num?> aNumNullable; // Error.
+//           ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<T extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:15:11: Error: Type argument 'int?' doesn't conform to the bound 'num' of the type variable 'T' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+//   A<int?> aIntNullable; // Error.
+//           ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<T extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:16:11: Error: Type argument 'Null' doesn't conform to the bound 'num' of the type variable 'T' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+//   A<Null> aNull; // Error.
+//           ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<T extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:17:21: Error: Type argument 'Object' doesn't conform to the bound 'num' of the type variable 'X' on 'FArgument'.
+//  - 'Object' is from 'dart:core'.
+// Try changing type arguments so that they conform to the bounds.
+//   FArgument<Object> fArgumentObject; // Error.
+//                     ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:7:19: Context: This is the type variable whose bound isn't conformed to.
+// typedef FArgument<X extends num> = Function(X);
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:18:19: Error: Type argument 'num?' doesn't conform to the bound 'num' of the type variable 'X' on 'FArgument'.
+// Try changing type arguments so that they conform to the bounds.
+//   FArgument<num?> fArgumentNumNullable; // Error.
+//                   ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:7:19: Context: This is the type variable whose bound isn't conformed to.
+// typedef FArgument<X extends num> = Function(X);
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:19:19: Error: Type argument 'int?' doesn't conform to the bound 'num' of the type variable 'X' on 'FArgument'.
+// Try changing type arguments so that they conform to the bounds.
+//   FArgument<int?> fArgumentIntNullable; // Error.
+//                   ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:7:19: Context: This is the type variable whose bound isn't conformed to.
+// typedef FArgument<X extends num> = Function(X);
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:20:19: Error: Type argument 'Null' doesn't conform to the bound 'num' of the type variable 'X' on 'FArgument'.
+// Try changing type arguments so that they conform to the bounds.
+//   FArgument<Null> fArgumentNull; // Error.
+//                   ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:7:19: Context: This is the type variable whose bound isn't conformed to.
+// typedef FArgument<X extends num> = Function(X);
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:21:19: Error: Type argument 'Object' doesn't conform to the bound 'num' of the type variable 'X' on 'FReturn'.
+//  - 'Object' is from 'dart:core'.
+// Try changing type arguments so that they conform to the bounds.
+//   FReturn<Object> fReturnObject; // Error.
+//                   ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:8:17: Context: This is the type variable whose bound isn't conformed to.
+// typedef FReturn<X extends num> = X Function();
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:22:17: Error: Type argument 'num?' doesn't conform to the bound 'num' of the type variable 'X' on 'FReturn'.
+// Try changing type arguments so that they conform to the bounds.
+//   FReturn<num?> fReturnNumNullable; // Error.
+//                 ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:8:17: Context: This is the type variable whose bound isn't conformed to.
+// typedef FReturn<X extends num> = X Function();
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:23:17: Error: Type argument 'int?' doesn't conform to the bound 'num' of the type variable 'X' on 'FReturn'.
+// Try changing type arguments so that they conform to the bounds.
+//   FReturn<int?> fReturnIntNullable; // Error.
+//                 ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:8:17: Context: This is the type variable whose bound isn't conformed to.
+// typedef FReturn<X extends num> = X Function();
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:24:17: Error: Type argument 'Null' doesn't conform to the bound 'num' of the type variable 'X' on 'FReturn'.
+// Try changing type arguments so that they conform to the bounds.
+//   FReturn<Null> fReturnNull; // Error.
+//                 ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:8:17: Context: This is the type variable whose bound isn't conformed to.
+// typedef FReturn<X extends num> = X Function();
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:25:17: Error: Type argument 'Object' doesn't conform to the bound 'num' of the type variable 'X' on 'FBoth'.
+//  - 'Object' is from 'dart:core'.
+// Try changing type arguments so that they conform to the bounds.
+//   FBoth<Object> fBothObject; // Error.
+//                 ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:9:15: Context: This is the type variable whose bound isn't conformed to.
+// typedef FBoth<X extends num> = X Function(X);
+//               ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:26:15: Error: Type argument 'num?' doesn't conform to the bound 'num' of the type variable 'X' on 'FBoth'.
+// Try changing type arguments so that they conform to the bounds.
+//   FBoth<num?> fBothNumNullable; // Error.
+//               ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:9:15: Context: This is the type variable whose bound isn't conformed to.
+// typedef FBoth<X extends num> = X Function(X);
+//               ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:27:15: Error: Type argument 'int?' doesn't conform to the bound 'num' of the type variable 'X' on 'FBoth'.
+// Try changing type arguments so that they conform to the bounds.
+//   FBoth<int?> fBothIntNullable; // Error.
+//               ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:9:15: Context: This is the type variable whose bound isn't conformed to.
+// typedef FBoth<X extends num> = X Function(X);
+//               ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:28:15: Error: Type argument 'Null' doesn't conform to the bound 'num' of the type variable 'X' on 'FBoth'.
+// Try changing type arguments so that they conform to the bounds.
+//   FBoth<Null> fBothNull; // Error.
+//               ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:9:15: Context: This is the type variable whose bound isn't conformed to.
+// typedef FBoth<X extends num> = X Function(X);
+//               ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:29:20: Error: Type argument 'Object' doesn't conform to the bound 'num' of the type variable 'X' on 'FNowhere'.
+//  - 'Object' is from 'dart:core'.
+// Try changing type arguments so that they conform to the bounds.
+//   FNowhere<Object> fNowhereObject; // Error.
+//                    ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:10:18: Context: This is the type variable whose bound isn't conformed to.
+// typedef FNowhere<X extends num> = Function();
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:30:18: Error: Type argument 'num?' doesn't conform to the bound 'num' of the type variable 'X' on 'FNowhere'.
+// Try changing type arguments so that they conform to the bounds.
+//   FNowhere<num?> fNowhereNumNullable; // Error.
+//                  ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:10:18: Context: This is the type variable whose bound isn't conformed to.
+// typedef FNowhere<X extends num> = Function();
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:31:18: Error: Type argument 'int?' doesn't conform to the bound 'num' of the type variable 'X' on 'FNowhere'.
+// Try changing type arguments so that they conform to the bounds.
+//   FNowhere<int?> fNowhereIntNullable; // Error.
+//                  ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:10:18: Context: This is the type variable whose bound isn't conformed to.
+// typedef FNowhere<X extends num> = Function();
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:32:18: Error: Type argument 'Null' doesn't conform to the bound 'num' of the type variable 'X' on 'FNowhere'.
+// Try changing type arguments so that they conform to the bounds.
+//   FNowhere<Null> fNowhereNull; // Error.
+//                  ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:10:18: Context: This is the type variable whose bound isn't conformed to.
+// typedef FNowhere<X extends num> = Function();
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:33:22: Error: Type argument 'Object?' doesn't conform to the bound 'num' of the type variable 'X' on 'FArgument'.
+//  - 'Object' is from 'dart:core'.
+// Try changing type arguments so that they conform to the bounds.
+//   FArgument<Object?> fArgumentObjectNullable; // Error.
+//                      ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:7:19: Context: This is the type variable whose bound isn't conformed to.
+// typedef FArgument<X extends num> = Function(X);
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:34:22: Error: Type argument 'dynamic' doesn't conform to the bound 'num' of the type variable 'X' on 'FArgument'.
+// Try changing type arguments so that they conform to the bounds.
+//   FArgument<dynamic> fArgumentDynamic; // Error.
+//                      ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:7:19: Context: This is the type variable whose bound isn't conformed to.
+// typedef FArgument<X extends num> = Function(X);
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue42429.dart:35:19: Error: Type argument 'void' doesn't conform to the bound 'num' of the type variable 'X' on 'FArgument'.
+// Try changing type arguments so that they conform to the bounds.
+//   FArgument<void> fArgumentVoid; // Error.
+//                   ^
+// pkg/front_end/testcases/nnbd/issue42429.dart:7:19: Context: This is the type variable whose bound isn't conformed to.
+// typedef FArgument<X extends num> = Function(X);
+//                   ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef FArgument<contravariant X extends core::num> = (X) → dynamic;
+typedef FReturn<X extends core::num> = () → X;
+typedef FBoth<invariant X extends core::num> = (X) → X;
+typedef FNowhere<unrelated X extends core::num> = () → dynamic;
+class A<T extends core::num> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T>
+    : super core::Object::•()
+    ;
+}
+static method foo() → dynamic {
+  self::A<core::Object> aObject;
+  self::A<core::num?> aNumNullable;
+  self::A<core::int?> aIntNullable;
+  self::A<Null> aNull;
+  (core::Object) → dynamic fArgumentObject;
+  (core::num?) → dynamic fArgumentNumNullable;
+  (core::int?) → dynamic fArgumentIntNullable;
+  (Null) → dynamic fArgumentNull;
+  () → core::Object fReturnObject;
+  () → core::num? fReturnNumNullable;
+  () → core::int? fReturnIntNullable;
+  () → Null fReturnNull;
+  (core::Object) → core::Object fBothObject;
+  (core::num?) → core::num? fBothNumNullable;
+  (core::int?) → core::int? fBothIntNullable;
+  (Null) → Null fBothNull;
+  () → dynamic fNowhereObject;
+  () → dynamic fNowhereNumNullable;
+  () → dynamic fNowhereIntNullable;
+  () → dynamic fNowhereNull;
+  (core::Object?) → dynamic fArgumentObjectNullable;
+  (dynamic) → dynamic fArgumentDynamic;
+  (void) → dynamic fArgumentVoid;
+  self::A<core::Object?> aObjectNullable;
+  self::A<dynamic> aDynamic;
+  self::A<void> aVoid;
+  self::A<core::num> aNum;
+  self::A<core::int> aInt;
+  self::A<Never> aNever;
+  (core::num) → dynamic fArgumentNum;
+  (core::int) → dynamic fArgumentInt;
+  (Never) → dynamic fArgumentNever;
+  () → core::Object? fReturnObjectNullable;
+  () → dynamic fReturnDynamic;
+  () → void fReturnVoid;
+  () → core::num fReturnNum;
+  () → core::int fReturnInt;
+  () → Never fReturnNever;
+  (core::Object?) → core::Object? fBothObjectNullable;
+  (dynamic) → dynamic fBothDynamic;
+  (void) → void fBothVoid;
+  (core::num) → core::num fBothNum;
+  (core::int) → core::int fBothInt;
+  (Never) → Never fBothNever;
+  () → dynamic fNowhereObjectNullable;
+  () → dynamic fNowhereDynamic;
+  () → dynamic fNowhereVoid;
+  () → dynamic fNowhereNum;
+  () → dynamic fNowhereInt;
+  () → dynamic fNowhereNever;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42433.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42433.dart.weak.modular.expect
new file mode 100644
index 0000000..b570b8b
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42433.dart.weak.modular.expect
@@ -0,0 +1,19 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef Test<contravariant T extends self::X> = (T?) → dynamic;
+class X extends core::Object {
+  synthetic constructor •() → self::X
+    : super core::Object::•()
+    ;
+}
+static method checkme<T extends self::X>(self::checkme::T? t) → dynamic {}
+static method main() → dynamic {
+  (self::X?) → dynamic t2 = #C2;
+}
+
+constants  {
+  #C1 = static-tearoff self::checkme
+  #C2 = instantiation #C1 <self::X*>
+}
diff --git a/pkg/front_end/testcases/nnbd/issue42434.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42434.dart.weak.modular.expect
new file mode 100644
index 0000000..e263ad8
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42434.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue42434.dart:7:21: Error: Type argument 'X/*1*/' doesn't conform to the bound 'A<X/*2*/>' of the type variable 'X' on 'A'.
+//  - 'X/*1*/' is from 'pkg/front_end/testcases/nnbd/issue42434.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue42434.dart'.
+//  - 'X/*2*/' is from 'pkg/front_end/testcases/nnbd/issue42434.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// typedef AAlias<X> = Function<X1 extends A<X>> ();
+//                     ^
+// pkg/front_end/testcases/nnbd/issue42434.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>> {}
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef AAlias<invariant X extends core::Object? = dynamic> = <X1 extends self::A<X%> = dynamic>() → dynamic;
+class A<X extends self::A<self::A::X> = self::A<dynamic>> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X>
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42434_2.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42434_2.dart.weak.modular.expect
new file mode 100644
index 0000000..88588f6
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42434_2.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue42434_2.dart:5:21: Error: Type argument 'X/*1*/' doesn't conform to the bound 'B<X/*2*/>' of the type variable 'X' on 'A'.
+//  - 'X/*1*/' is from 'pkg/front_end/testcases/nnbd/issue42434_2.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/issue42434_2.dart'.
+//  - 'X/*2*/' is from 'pkg/front_end/testcases/nnbd/issue42434_2.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// typedef AAlias<X> = Function<X1 extends A<X>> ();
+//                     ^
+// pkg/front_end/testcases/nnbd/issue42434_2.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef A<X extends B<X>> = Function();
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef AAlias<unrelated X extends core::Object? = dynamic> = <X1 extends () → dynamic = dynamic>() → dynamic;
+typedef A<unrelated X extends self::B<X> = self::B<dynamic>> = () → dynamic;
+class B<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::X%>
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42459.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42459.dart.weak.modular.expect
new file mode 100644
index 0000000..fe7ca67
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42459.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue42459.dart:10:7: Error: A value must be explicitly returned from a non-void function.
+//       return;
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test() → dynamic {
+  (dynamic x) → core::int? {
+    if(x as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool) {
+      return 1;
+    }
+    else {
+      return invalid-expression "pkg/front_end/testcases/nnbd/issue42459.dart:10:7: Error: A value must be explicitly returned from a non-void function.
+      return;
+      ^" in null;
+    }
+  };
+  function local(dynamic x) → void {
+    if(x as{TypeError,ForDynamic,ForNonNullableByDefault} core::bool) {
+      return core::print("");
+    }
+    else {
+      return;
+    }
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42504.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42504.dart.weak.modular.expect
new file mode 100644
index 0000000..62138bc
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42504.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class ImageStreamCompleter extends core::Object {
+  synthetic constructor •() → self::ImageStreamCompleter
+    : super core::Object::•()
+    ;
+  abstract method addListener() → void;
+}
+class _LiveImage extends core::Object {
+  static factory •(self::ImageStreamCompleter a) → self::_LiveImage
+    return throw new core::UnimplementedError::•();
+}
+abstract class Foo extends core::Object {
+  synthetic constructor •() → self::Foo
+    : super core::Object::•()
+    ;
+  abstract get _pendingImages() → dynamic;
+  method putIfAbsent(core::Object key, () → self::ImageStreamCompleter loader) → self::ImageStreamCompleter? {
+    assert(!(key == null));
+    assert(!(loader == null));
+    self::ImageStreamCompleter? result = (let final dynamic #t1 = this.{self::Foo::_pendingImages}{dynamic}{dynamic}.[](key) in #t1 == null ?{dynamic} null : #t1{dynamic}.completer) as{TypeError,ForDynamic,ForNonNullableByDefault} self::ImageStreamCompleter?;
+    if(!(result == null)) {
+      return result{self::ImageStreamCompleter};
+    }
+    try {
+      result = loader(){() → self::ImageStreamCompleter};
+      self::_LiveImage::•(result{self::ImageStreamCompleter});
+    }
+    on core::Object catch(final core::Object error) {
+      return null;
+    }
+    result{self::ImageStreamCompleter}.{self::ImageStreamCompleter::addListener}(){() → void};
+    return result{self::ImageStreamCompleter};
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42540.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42540.dart.weak.modular.expect
new file mode 100644
index 0000000..aaf931d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42540.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+static method getNull() → dynamic
+  return null;
+static method fn() → asy::Future<core::Object> async {
+  core::Object o = await self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} core::Object;
+  return await self::getNull() as{TypeError,ForDynamic,ForNonNullableByDefault} FutureOr<core::Object>;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42546.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42546.dart.weak.modular.expect
new file mode 100644
index 0000000..8563b46
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42546.dart.weak.modular.expect
@@ -0,0 +1,66 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue42546.dart:14:58: Error: A value of type 'Divergent<int>' can't be returned from an async function with return type 'Future<Divergent<Divergent<Divergent<int>>>>'.
+//  - 'Divergent' is from 'pkg/front_end/testcases/nnbd/issue42546.dart'.
+//  - 'Future' is from 'dart:async'.
+//   Future<Divergent<Divergent<int>>> x = (() async => new Divergent<int>())();
+//                                                          ^
+//
+// pkg/front_end/testcases/nnbd/issue42546.dart:14:75: Error: A value of type 'Future<Divergent<Divergent<Divergent<int>>>>' can't be assigned to a variable of type 'Future<Divergent<Divergent<int>>>'.
+//  - 'Future' is from 'dart:async'.
+//  - 'Divergent' is from 'pkg/front_end/testcases/nnbd/issue42546.dart'.
+//   Future<Divergent<Divergent<int>>> x = (() async => new Divergent<int>())();
+//                                                                           ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class Divergent<T extends core::Object? = dynamic> extends core::Object implements asy::Future<self::Divergent<self::Divergent<self::Divergent::T%>>> {
+  synthetic constructor •() → self::Divergent<self::Divergent::T%>
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation invocation) → dynamic
+    return super.{core::Object::noSuchMethod}(invocation);
+  no-such-method-forwarder method /* from org-dartlang-sdk:///sdk/lib/async/future.dart */ catchError(core::Function onError, {(core::Object) →? core::bool test = #C1}) → asy::Future<self::Divergent<self::Divergent<self::Divergent::T%>>>
+    return this.{self::Divergent::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[onError]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C4: test}))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} asy::Future<self::Divergent<self::Divergent<self::Divergent::T%>>>;
+  no-such-method-forwarder method /* from org-dartlang-sdk:///sdk/lib/async/future.dart */ whenComplete(() → FutureOr<void>action) → asy::Future<self::Divergent<self::Divergent<self::Divergent::T%>>>
+    return this.{self::Divergent::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} asy::Future<self::Divergent<self::Divergent<self::Divergent::T%>>>;
+  no-such-method-forwarder method /* from org-dartlang-sdk:///sdk/lib/async/future.dart */ timeout(core::Duration timeLimit, {covariant-by-class () →? FutureOr<self::Divergent<self::Divergent<self::Divergent::T%>>>onTimeout = #C1}) → asy::Future<self::Divergent<self::Divergent<self::Divergent::T%>>>
+    return this.{self::Divergent::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[timeLimit]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C8: onTimeout}))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} asy::Future<self::Divergent<self::Divergent<self::Divergent::T%>>>;
+  no-such-method-forwarder method /* from org-dartlang-sdk:///sdk/lib/async/future.dart */ then<R extends core::Object? = dynamic>((self::Divergent<self::Divergent<self::Divergent::T%>>) → FutureOr<self::Divergent::then::R%>onValue, {core::Function? onError = #C1}) → asy::Future<self::Divergent::then::R%>
+    return this.{self::Divergent::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 0, core::List::unmodifiable<core::Type*>(<core::Type*>[self::Divergent::then::R%]), core::List::unmodifiable<dynamic>(<dynamic>[onValue]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C10: onError}))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} asy::Future<self::Divergent::then::R%>;
+  no-such-method-forwarder method /* from org-dartlang-sdk:///sdk/lib/async/future.dart */ asStream() → asy::Stream<self::Divergent<self::Divergent<self::Divergent::T%>>>
+    return this.{self::Divergent::noSuchMethod}(new core::_InvocationMirror::_withType(#C11, 0, #C3, #C12, core::Map::unmodifiable<core::Symbol*, dynamic>(#C6))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} asy::Stream<self::Divergent<self::Divergent<self::Divergent::T%>>>;
+}
+static method test() → dynamic async {
+  asy::Future<self::Divergent<self::Divergent<core::int>>> x = invalid-expression "pkg/front_end/testcases/nnbd/issue42546.dart:14:75: Error: A value of type 'Future<Divergent<Divergent<Divergent<int>>>>' can't be assigned to a variable of type 'Future<Divergent<Divergent<int>>>'.
+ - 'Future' is from 'dart:async'.
+ - 'Divergent' is from 'pkg/front_end/testcases/nnbd/issue42546.dart'.
+  Future<Divergent<Divergent<int>>> x = (() async => new Divergent<int>())();
+                                                                          ^" in (() → asy::Future<self::Divergent<self::Divergent<self::Divergent<core::int>>>> async => invalid-expression "pkg/front_end/testcases/nnbd/issue42546.dart:14:58: Error: A value of type 'Divergent<int>' can't be returned from an async function with return type 'Future<Divergent<Divergent<Divergent<int>>>>'.
+ - 'Divergent' is from 'pkg/front_end/testcases/nnbd/issue42546.dart'.
+ - 'Future' is from 'dart:async'.
+  Future<Divergent<Divergent<int>>> x = (() async => new Divergent<int>())();
+                                                         ^" in new self::Divergent::•<core::int>() as{TypeError,ForNonNullableByDefault} self::Divergent<self::Divergent<self::Divergent<core::int>>>)(){() → asy::Future<self::Divergent<self::Divergent<self::Divergent<core::int>>>>} as{TypeError,ForNonNullableByDefault} asy::Future<self::Divergent<self::Divergent<core::int>>>;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+  #C2 = #catchError
+  #C3 = <core::Type*>[]
+  #C4 = #test
+  #C5 = #whenComplete
+  #C6 = <core::Symbol*, dynamic>{)
+  #C7 = #timeout
+  #C8 = #onTimeout
+  #C9 = #then
+  #C10 = #onError
+  #C11 = #asStream
+  #C12 = <dynamic>[]
+}
diff --git a/pkg/front_end/testcases/nnbd/issue42579.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42579.dart.weak.modular.expect
new file mode 100644
index 0000000..6ee7128
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42579.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+}
+static method foo<S extends core::Object? = dynamic>() → self::foo::S%
+  return throw "foo";
+static method bar<R extends core::Object? = dynamic>(self::A<self::bar::R%> a) → dynamic {}
+static method baz() → dynamic
+  return self::bar<core::Object?>(self::foo<self::A<core::Object?>>());
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42579_2.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42579_2.dart.weak.modular.expect
new file mode 100644
index 0000000..7b83456
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42579_2.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue42579_2.dart:19:32: Error: The method 'unknown' isn't defined for the class 'Object'.
+//  - 'Object' is from 'dart:core'.
+// Try correcting the name to the name of an existing method, or defining a method named 'unknown'.
+//   wrap2(() => foo()..property?.unknown());
+//                                ^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+  get property() → self::A::T%
+    return throw "A.property";
+}
+static method foo<S extends core::Object? = dynamic>() → self::foo::S%
+  return throw "foo";
+static method wrap<R extends core::Object? = dynamic>(() → self::wrap::R% f) → dynamic {}
+static method wrap2<R extends core::Object? = dynamic>(() → self::A<self::wrap2::R%> f) → dynamic {}
+static method bar() → dynamic {
+  new self::A::•<dynamic>().{self::A::property}{dynamic}{dynamic}.unknown();
+  self::foo<dynamic>(){dynamic}.unknown();
+  self::wrap<dynamic>(() → dynamic => let final dynamic #t1 = self::foo<dynamic>() in block {
+    #t1{dynamic}.unknown();
+  } =>#t1);
+  self::wrap2<core::Object?>(() → self::A<core::Object?> => let final self::A<core::Object?> #t2 = self::foo<self::A<core::Object?>>() in block {
+    let final core::Object? #t3 = #t2.{self::A::property}{core::Object?} in #t3 == null ?{dynamic} null : invalid-expression "pkg/front_end/testcases/nnbd/issue42579_2.dart:19:32: Error: The method 'unknown' isn't defined for the class 'Object'.
+ - 'Object' is from 'dart:core'.
+Try correcting the name to the name of an existing method, or defining a method named 'unknown'.
+  wrap2(() => foo()..property?.unknown());
+                               ^^^^^^^" in #t3{core::Object}{<unresolved>}.unknown();
+  } =>#t2);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42579_3.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42579_3.dart.weak.modular.expect
new file mode 100644
index 0000000..2763847
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42579_3.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue42579_3.dart:16:25: Error: The method 'unknown' isn't defined for the class 'Object'.
+//  - 'Object' is from 'dart:core'.
+// Try correcting the name to the name of an existing method, or defining a method named 'unknown'.
+//   foo(() => B()..y1[0]?.unknown());
+//                         ^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue42579_3.dart:17:25: Error: The method 'unknown' isn't defined for the class 'Object'.
+//  - 'Object' is from 'dart:core'.
+// Try correcting the name to the name of an existing method, or defining a method named 'unknown'.
+//   foo(() => B()..y2[0]?.unknown());
+//                         ^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+}
+class B<Y1 extends core::Object? = dynamic, Y2 extends core::List<self::B::Y3%> = core::List<dynamic>, Y3 extends core::Object? = dynamic> extends self::A<self::B::Y1%> {
+  synthetic constructor •() → self::B<self::B::Y1%, self::B::Y2, self::B::Y3%>
+    : super self::A::•()
+    ;
+  get y1() → self::B::Y1%
+    return throw "B.y1";
+  get y2() → self::B::Y2
+    return throw "B.y2";
+  get y3() → self::B::Y3%
+    return throw "B.y3";
+}
+static method foo<Z extends core::Object? = dynamic>(() → self::A<core::List<self::foo::Z%>> f) → dynamic {}
+static method bar() → dynamic {
+  self::foo<core::Object?>(() → self::B<core::List<core::Object?>, core::List<core::Object?>, dynamic> => let final self::B<core::List<core::Object?>, core::List<core::Object?>, dynamic> #t1 = new self::B::•<core::List<core::Object?>, core::List<core::Object?>, dynamic>() in block {
+    let final core::Object? #t2 = #t1.{self::B::y1}{core::List<core::Object?>}.{core::List::[]}(0){(core::int) → core::Object?} in #t2 == null ?{dynamic} null : invalid-expression "pkg/front_end/testcases/nnbd/issue42579_3.dart:16:25: Error: The method 'unknown' isn't defined for the class 'Object'.
+ - 'Object' is from 'dart:core'.
+Try correcting the name to the name of an existing method, or defining a method named 'unknown'.
+  foo(() => B()..y1[0]?.unknown());
+                        ^^^^^^^" in #t2{core::Object}{<unresolved>}.unknown();
+  } =>#t1);
+  self::foo<core::Object?>(() → self::B<core::List<core::Object?>, core::List<core::Object?>, dynamic> => let final self::B<core::List<core::Object?>, core::List<core::Object?>, dynamic> #t3 = new self::B::•<core::List<core::Object?>, core::List<core::Object?>, dynamic>() in block {
+    let final core::Object? #t4 = #t3.{self::B::y2}{core::List<core::Object?>}.{core::List::[]}(0){(core::int) → core::Object?} in #t4 == null ?{dynamic} null : invalid-expression "pkg/front_end/testcases/nnbd/issue42579_3.dart:17:25: Error: The method 'unknown' isn't defined for the class 'Object'.
+ - 'Object' is from 'dart:core'.
+Try correcting the name to the name of an existing method, or defining a method named 'unknown'.
+  foo(() => B()..y2[0]?.unknown());
+                        ^^^^^^^" in #t4{core::Object}{<unresolved>}.unknown();
+  } =>#t3);
+  self::foo<core::Object?>(() → self::B<core::List<core::Object?>, core::List<core::Object?>, dynamic> => let final self::B<core::List<core::Object?>, core::List<core::Object?>, dynamic> #t5 = new self::B::•<core::List<core::Object?>, core::List<core::Object?>, dynamic>() in block {
+    let final dynamic #t6 = #t5.{self::B::y3}{dynamic} in #t6 == null ?{dynamic} null : #t6{dynamic}.unknown();
+  } =>#t5);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42603.dart.strong.expect b/pkg/front_end/testcases/nnbd/issue42603.dart.strong.expect
index 1717f29..7d802ac 100644
--- a/pkg/front_end/testcases/nnbd/issue42603.dart.strong.expect
+++ b/pkg/front_end/testcases/nnbd/issue42603.dart.strong.expect
@@ -9,7 +9,7 @@
 // pkg/front_end/testcases/nnbd/issue42603.dart:18:17: Error: The method 'E.==' has fewer positional arguments than those of overridden method 'Object.=='.
 //   bool operator ==() => true;
 //                 ^
-// sdk/lib/_internal/vm/lib/object_patch.dart:29:26: Context: This is the overridden method ('==').
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
 //   external bool operator ==(Object other);
 //                          ^
 //
diff --git a/pkg/front_end/testcases/nnbd/issue42603.dart.weak.expect b/pkg/front_end/testcases/nnbd/issue42603.dart.weak.expect
index 1717f29..7d802ac 100644
--- a/pkg/front_end/testcases/nnbd/issue42603.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd/issue42603.dart.weak.expect
@@ -9,7 +9,7 @@
 // pkg/front_end/testcases/nnbd/issue42603.dart:18:17: Error: The method 'E.==' has fewer positional arguments than those of overridden method 'Object.=='.
 //   bool operator ==() => true;
 //                 ^
-// sdk/lib/_internal/vm/lib/object_patch.dart:29:26: Context: This is the overridden method ('==').
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
 //   external bool operator ==(Object other);
 //                          ^
 //
diff --git a/pkg/front_end/testcases/nnbd/issue42603.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42603.dart.weak.modular.expect
new file mode 100644
index 0000000..7d802ac
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42603.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue42603.dart:18:17: Error: Operator '==' should have exactly one parameter.
+//   bool operator ==() => true;
+//                 ^^
+//
+// pkg/front_end/testcases/nnbd/issue42603.dart:18:17: Error: The method 'E.==' has fewer positional arguments than those of overridden method 'Object.=='.
+//   bool operator ==() => true;
+//                 ^
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
+//   external bool operator ==(Object other);
+//                          ^
+//
+// pkg/front_end/testcases/nnbd/issue42603.dart:22:17: Error: The method 'F.==' has more required arguments than those of overridden method 'E.=='.
+//   bool operator ==(Object? other) => super == other;
+//                 ^
+// pkg/front_end/testcases/nnbd/issue42603.dart:18:17: Context: This is the overridden method ('==').
+//   bool operator ==() => true;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/issue42603.dart:22:44: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//   bool operator ==(Object? other) => super == other;
+//                                            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  operator ==(core::Object other) → core::bool
+    return true;
+}
+class D extends self::C {
+  synthetic constructor •() → self::D
+    : super self::C::•()
+    ;
+  operator ==(core::Object? other) → core::bool
+    return super.{self::C::==}(other);
+  method method1(dynamic o) → core::bool
+    return super.{self::C::==}(o);
+  method method2(Null o) → core::bool
+    return super.{self::C::==}(o);
+}
+class E extends core::Object {
+  synthetic constructor •() → self::E
+    : super core::Object::•()
+    ;
+  operator ==() → core::bool
+    return true;
+}
+class F extends self::E {
+  synthetic constructor •() → self::F
+    : super self::E::•()
+    ;
+  operator ==(core::Object? other) → core::bool
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue42603.dart:22:44: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+  bool operator ==(Object? other) => super == other;
+                                           ^" in super.{self::E::==}(other);
+}
+static method main() → dynamic {
+  self::expect(true, new self::D::•() =={self::D::==}{(core::Object?) → core::bool} new self::D::•());
+  self::expect(false, new self::D::•().{self::D::method1}(null){(dynamic) → core::bool});
+  self::expect(false, new self::D::•().{self::D::method2}(null){(Null) → core::bool});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/nnbd/issue42603.dart.weak.outline.expect b/pkg/front_end/testcases/nnbd/issue42603.dart.weak.outline.expect
index f1a33e9..390818a 100644
--- a/pkg/front_end/testcases/nnbd/issue42603.dart.weak.outline.expect
+++ b/pkg/front_end/testcases/nnbd/issue42603.dart.weak.outline.expect
@@ -9,7 +9,7 @@
 // pkg/front_end/testcases/nnbd/issue42603.dart:18:17: Error: The method 'E.==' has fewer positional arguments than those of overridden method 'Object.=='.
 //   bool operator ==() => true;
 //                 ^
-// sdk/lib/_internal/vm/lib/object_patch.dart:29:26: Context: This is the overridden method ('==').
+// sdk/lib/_internal/vm/lib/object_patch.dart:21:26: Context: This is the overridden method ('==').
 //   external bool operator ==(Object other);
 //                          ^
 //
diff --git a/pkg/front_end/testcases/nnbd/issue42607.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42607.dart.weak.modular.expect
new file mode 100644
index 0000000..47b797f
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42607.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method test() → dynamic {
+  core::int* x = 3;
+  let final core::int* #t1 = x in #t1 == null ?{core::bool*} null : #t1.{core::int::isEven}{core::bool*};
+  x = null;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42743.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42743.dart.weak.modular.expect
new file mode 100644
index 0000000..3e6d749
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42743.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+static method main() → dynamic async {
+  core::bool b = (() → core::bool => true)(){() → core::bool};
+  (dynamic _) → core::int? {
+    if(b)
+      return 42;
+  };
+  (dynamic _) → asy::Future<core::int?> async {
+    if(b)
+      return 42;
+  };
+}
diff --git a/pkg/front_end/testcases/nnbd/issue42758.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42758.dart.weak.modular.expect
new file mode 100644
index 0000000..7478ccc
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42758.dart.weak.modular.expect
@@ -0,0 +1,290 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:7:17: Warning: Operand of null-aware operation '...?' has type 'Never' which excludes null.
+//   var l2 = [...?n1];
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:8:16: Error: Can't spread a value with static type 'Never?'.
+//   var l3 = [...n2];
+//                ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:10:16: Error: Can't spread a value with static type 'Null'.
+//   var l5 = [...n3];
+//                ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:13:17: Warning: Operand of null-aware operation '...?' has type 'Never' which excludes null.
+//   var s2 = {...?n1, n1};
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:14:16: Error: Can't spread a value with static type 'Never?'.
+//   var s3 = {...n2, n1};
+//                ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:16:16: Error: Can't spread a value with static type 'Null'.
+//   var s5 = {...n3, n1};
+//                ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:19:17: Warning: Operand of null-aware operation '...?' has type 'Never' which excludes null.
+//   var m2 = {...?n1, n1: n1};
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:20:16: Error: Can't spread a value with static type 'Never?'.
+//   var m3 = {...n2, n1: n1};
+//                ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:22:16: Error: Can't spread a value with static type 'Null'.
+//   var m5 = {...n3, n1: n1};
+//                ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:29:17: Warning: Operand of null-aware operation '...?' has type 'N1' which excludes null.
+//   var l2 = [...?n1];
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:30:16: Error: Can't spread a value with static type 'N2'.
+//   var l3 = [...n2];
+//                ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:32:16: Error: Can't spread a value with static type 'N3'.
+//   var l5 = [...n3];
+//                ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:35:17: Warning: Operand of null-aware operation '...?' has type 'N1' which excludes null.
+//   var s2 = {...?n1, n1};
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:36:16: Error: Can't spread a value with static type 'N2'.
+//   var s3 = {...n2, n1};
+//                ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:38:16: Error: Can't spread a value with static type 'N3'.
+//   var s5 = {...n3, n1};
+//                ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:41:17: Warning: Operand of null-aware operation '...?' has type 'N1' which excludes null.
+//   var m2 = {...?n1, n1: n1};
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:42:16: Error: Can't spread a value with static type 'N2'.
+//   var m3 = {...n2, n1: n1};
+//                ^
+//
+// pkg/front_end/testcases/nnbd/issue42758.dart:44:16: Error: Can't spread a value with static type 'N3'.
+//   var m5 = {...n3, n1: n1};
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+import "dart:collection" as col;
+
+static method test1(Never n1, Never? n2, Null n3) → dynamic {
+  core::List<Never> l1 = block {
+    final core::List<Never> #t1 = core::List::of<Never>(let final Never #t2 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."));
+  } =>#t1;
+  core::List<Never> l2 = block {
+    final core::List<Never> #t3 = <Never>[];
+    final core::Iterable<Never>? #t4 = let final Never #t5 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    if(!(#t4 == null))
+      #t3.{core::List::addAll}{Invariant}(#t4{core::Iterable<Never>}){(core::Iterable<Never>) → void};
+  } =>#t3;
+  core::List<dynamic> l3 = <dynamic>[invalid-expression "pkg/front_end/testcases/nnbd/issue42758.dart:8:16: Error: Can't spread a value with static type 'Never?'.
+  var l3 = [...n2];
+               ^"];
+  core::List<Never> l4 = block {
+    final core::List<Never> #t6 = <Never>[];
+    final core::Iterable<Never>? #t7 = n2;
+    if(!(#t7 == null))
+      #t6.{core::List::addAll}{Invariant}(#t7{core::Iterable<Never>}){(core::Iterable<Never>) → void};
+  } =>#t6;
+  core::List<dynamic> l5 = <dynamic>[invalid-expression "pkg/front_end/testcases/nnbd/issue42758.dart:10:16: Error: Can't spread a value with static type 'Null'.
+  var l5 = [...n3];
+               ^"];
+  core::List<Never> l6 = block {
+    final core::List<Never> #t8 = <Never>[];
+    final core::Iterable<Never>? #t9 = n3;
+    if(!(#t9 == null))
+      #t8.{core::List::addAll}{Invariant}(#t9{core::Iterable<Never>}){(core::Iterable<Never>) → void};
+  } =>#t8;
+  core::Set<Never> s1 = block {
+    final core::Set<Never> #t10 = col::LinkedHashSet::of<Never>(let final Never #t11 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."));
+    #t10.{core::Set::add}{Invariant}(let final Never #t12 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(Never) → core::bool};
+  } =>#t10;
+  core::Set<Never> s2 = block {
+    final core::Set<Never> #t13 = col::LinkedHashSet::•<Never>();
+    final core::Iterable<Never>? #t14 = let final Never #t15 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    if(!(#t14 == null))
+      #t13.{core::Set::addAll}{Invariant}(#t14{core::Iterable<Never>}){(core::Iterable<Never>) → void};
+    #t13.{core::Set::add}{Invariant}(let final Never #t16 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(Never) → core::bool};
+  } =>#t13;
+  core::Set<dynamic> s3 = block {
+    final core::Set<dynamic> #t17 = col::LinkedHashSet::•<dynamic>();
+    #t17.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue42758.dart:14:16: Error: Can't spread a value with static type 'Never?'.
+  var s3 = {...n2, n1};
+               ^"){(dynamic) → core::bool};
+    #t17.{core::Set::add}{Invariant}(let final Never #t18 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(dynamic) → core::bool};
+  } =>#t17;
+  core::Set<Never> s4 = block {
+    final core::Set<Never> #t19 = col::LinkedHashSet::•<Never>();
+    final core::Iterable<Never>? #t20 = n2;
+    if(!(#t20 == null))
+      #t19.{core::Set::addAll}{Invariant}(#t20{core::Iterable<Never>}){(core::Iterable<Never>) → void};
+    #t19.{core::Set::add}{Invariant}(let final Never #t21 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(Never) → core::bool};
+  } =>#t19;
+  core::Set<dynamic> s5 = block {
+    final core::Set<dynamic> #t22 = col::LinkedHashSet::•<dynamic>();
+    #t22.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue42758.dart:16:16: Error: Can't spread a value with static type 'Null'.
+  var s5 = {...n3, n1};
+               ^"){(dynamic) → core::bool};
+    #t22.{core::Set::add}{Invariant}(let final Never #t23 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(dynamic) → core::bool};
+  } =>#t22;
+  core::Set<Never> s6 = block {
+    final core::Set<Never> #t24 = col::LinkedHashSet::•<Never>();
+    final core::Iterable<Never>? #t25 = n3;
+    if(!(#t25 == null))
+      #t24.{core::Set::addAll}{Invariant}(#t25{core::Iterable<Never>}){(core::Iterable<Never>) → void};
+    #t24.{core::Set::add}{Invariant}(let final Never #t26 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(Never) → core::bool};
+  } =>#t24;
+  core::Map<Never, Never> m1 = block {
+    final core::Map<Never, Never> #t27 = <Never, Never>{};
+    for (final core::MapEntry<Never, Never> #t28 in (let final Never #t29 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")).{core::Map::entries}{core::Iterable<core::MapEntry<Never, Never>>})
+      #t27.{core::Map::[]=}{Invariant}(#t28.{core::MapEntry::key}{Never}, #t28.{core::MapEntry::value}{Never}){(Never, Never) → void};
+    #t27.{core::Map::[]=}{Invariant}(let final Never #t30 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."), let final Never #t31 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(Never, Never) → void};
+  } =>#t27;
+  core::Map<Never, Never> m2 = block {
+    final core::Map<Never, Never> #t32 = <Never, Never>{};
+    final core::Map<Never, Never>? #t33 = let final Never #t34 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    if(!(#t33 == null))
+      for (final core::MapEntry<Never, Never> #t35 in #t33{core::Map<Never, Never>}.{core::Map::entries}{core::Iterable<core::MapEntry<Never, Never>>})
+        #t32.{core::Map::[]=}{Invariant}(#t35.{core::MapEntry::key}{Never}, #t35.{core::MapEntry::value}{Never}){(Never, Never) → void};
+    #t32.{core::Map::[]=}{Invariant}(let final Never #t36 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."), let final Never #t37 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(Never, Never) → void};
+  } =>#t32;
+  core::Map<dynamic, dynamic> m3 = <dynamic, dynamic>{invalid-expression "pkg/front_end/testcases/nnbd/issue42758.dart:20:16: Error: Can't spread a value with static type 'Never?'.
+  var m3 = {...n2, n1: n1};
+               ^": null, let final Never #t38 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."): let final Never #t39 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")};
+  core::Map<Never, Never> m4 = block {
+    final core::Map<Never, Never> #t40 = <Never, Never>{};
+    final core::Map<Never, Never>? #t41 = n2;
+    if(!(#t41 == null))
+      for (final core::MapEntry<Never, Never> #t42 in #t41{core::Map<Never, Never>}.{core::Map::entries}{core::Iterable<core::MapEntry<Never, Never>>})
+        #t40.{core::Map::[]=}{Invariant}(#t42.{core::MapEntry::key}{Never}, #t42.{core::MapEntry::value}{Never}){(Never, Never) → void};
+    #t40.{core::Map::[]=}{Invariant}(let final Never #t43 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."), let final Never #t44 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(Never, Never) → void};
+  } =>#t40;
+  core::Map<dynamic, dynamic> m5 = <dynamic, dynamic>{invalid-expression "pkg/front_end/testcases/nnbd/issue42758.dart:22:16: Error: Can't spread a value with static type 'Null'.
+  var m5 = {...n3, n1: n1};
+               ^": null, let final Never #t45 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."): let final Never #t46 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")};
+  core::Map<Never, Never> m6 = block {
+    final core::Map<Never, Never> #t47 = <Never, Never>{};
+    final core::Map<Never, Never>? #t48 = n3;
+    if(!(#t48 == null))
+      for (final core::MapEntry<Never, Never> #t49 in #t48{core::Map<Never, Never>}.{core::Map::entries}{core::Iterable<core::MapEntry<Never, Never>>})
+        #t47.{core::Map::[]=}{Invariant}(#t49.{core::MapEntry::key}{Never}, #t49.{core::MapEntry::value}{Never}){(Never, Never) → void};
+    #t47.{core::Map::[]=}{Invariant}(let final Never #t50 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."), let final Never #t51 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(Never, Never) → void};
+  } =>#t47;
+}
+static method test2<N1 extends Never, N2 extends Never?, N3 extends Null>(self::test2::N1 n1, self::test2::N2% n2, self::test2::N3% n3) → dynamic {
+  core::List<Never> l1 = block {
+    final core::List<Never> #t52 = core::List::of<Never>(let final self::test2::N1 #t53 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."));
+  } =>#t52;
+  core::List<Never> l2 = block {
+    final core::List<Never> #t54 = <Never>[];
+    final core::Iterable<Never>? #t55 = let final self::test2::N1 #t56 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    if(!(#t55 == null))
+      #t54.{core::List::addAll}{Invariant}(#t55{core::Iterable<Never>}){(core::Iterable<Never>) → void};
+  } =>#t54;
+  core::List<dynamic> l3 = <dynamic>[invalid-expression "pkg/front_end/testcases/nnbd/issue42758.dart:30:16: Error: Can't spread a value with static type 'N2'.
+  var l3 = [...n2];
+               ^"];
+  core::List<Never> l4 = block {
+    final core::List<Never> #t57 = <Never>[];
+    final core::Iterable<Never>? #t58 = n2;
+    if(!(#t58 == null))
+      #t57.{core::List::addAll}{Invariant}(#t58{core::Iterable<Never>}){(core::Iterable<Never>) → void};
+  } =>#t57;
+  core::List<dynamic> l5 = <dynamic>[invalid-expression "pkg/front_end/testcases/nnbd/issue42758.dart:32:16: Error: Can't spread a value with static type 'N3'.
+  var l5 = [...n3];
+               ^"];
+  core::List<Never> l6 = block {
+    final core::List<Never> #t59 = <Never>[];
+    final core::Iterable<Never>? #t60 = n3;
+    if(!(#t60 == null))
+      #t59.{core::List::addAll}{Invariant}(#t60{core::Iterable<Never>}){(core::Iterable<Never>) → void};
+  } =>#t59;
+  core::Set<self::test2::N1> s1 = block {
+    final core::Set<self::test2::N1> #t61 = col::LinkedHashSet::of<self::test2::N1>(let final self::test2::N1 #t62 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."));
+    #t61.{core::Set::add}{Invariant}(let final self::test2::N1 #t63 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(self::test2::N1) → core::bool};
+  } =>#t61;
+  core::Set<self::test2::N1> s2 = block {
+    final core::Set<self::test2::N1> #t64 = col::LinkedHashSet::•<self::test2::N1>();
+    final core::Iterable<self::test2::N1>? #t65 = let final self::test2::N1 #t66 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    if(!(#t65 == null))
+      #t64.{core::Set::addAll}{Invariant}(#t65{core::Iterable<self::test2::N1>}){(core::Iterable<self::test2::N1>) → void};
+    #t64.{core::Set::add}{Invariant}(let final self::test2::N1 #t67 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(self::test2::N1) → core::bool};
+  } =>#t64;
+  core::Set<dynamic> s3 = block {
+    final core::Set<dynamic> #t68 = col::LinkedHashSet::•<dynamic>();
+    #t68.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue42758.dart:36:16: Error: Can't spread a value with static type 'N2'.
+  var s3 = {...n2, n1};
+               ^"){(dynamic) → core::bool};
+    #t68.{core::Set::add}{Invariant}(let final self::test2::N1 #t69 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(dynamic) → core::bool};
+  } =>#t68;
+  core::Set<self::test2::N1> s4 = block {
+    final core::Set<self::test2::N1> #t70 = col::LinkedHashSet::•<self::test2::N1>();
+    final core::Iterable<self::test2::N1>? #t71 = n2;
+    if(!(#t71 == null))
+      #t70.{core::Set::addAll}{Invariant}(#t71{core::Iterable<self::test2::N1>}){(core::Iterable<self::test2::N1>) → void};
+    #t70.{core::Set::add}{Invariant}(let final self::test2::N1 #t72 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(self::test2::N1) → core::bool};
+  } =>#t70;
+  core::Set<dynamic> s5 = block {
+    final core::Set<dynamic> #t73 = col::LinkedHashSet::•<dynamic>();
+    #t73.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue42758.dart:38:16: Error: Can't spread a value with static type 'N3'.
+  var s5 = {...n3, n1};
+               ^"){(dynamic) → core::bool};
+    #t73.{core::Set::add}{Invariant}(let final self::test2::N1 #t74 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(dynamic) → core::bool};
+  } =>#t73;
+  core::Set<self::test2::N1> s6 = block {
+    final core::Set<self::test2::N1> #t75 = col::LinkedHashSet::•<self::test2::N1>();
+    final core::Iterable<self::test2::N1>? #t76 = n3;
+    if(!(#t76 == null))
+      #t75.{core::Set::addAll}{Invariant}(#t76{core::Iterable<self::test2::N1>}){(core::Iterable<self::test2::N1>) → void};
+    #t75.{core::Set::add}{Invariant}(let final self::test2::N1 #t77 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(self::test2::N1) → core::bool};
+  } =>#t75;
+  core::Map<self::test2::N1, self::test2::N1> m1 = block {
+    final core::Map<self::test2::N1, self::test2::N1> #t78 = <self::test2::N1, self::test2::N1>{};
+    for (final core::MapEntry<self::test2::N1, self::test2::N1> #t79 in (let final self::test2::N1 #t80 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")).{core::Map::entries}{core::Iterable<core::MapEntry<self::test2::N1, self::test2::N1>>})
+      #t78.{core::Map::[]=}{Invariant}(#t79.{core::MapEntry::key}{self::test2::N1}, #t79.{core::MapEntry::value}{self::test2::N1}){(self::test2::N1, self::test2::N1) → void};
+    #t78.{core::Map::[]=}{Invariant}(let final self::test2::N1 #t81 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."), let final self::test2::N1 #t82 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(self::test2::N1, self::test2::N1) → void};
+  } =>#t78;
+  core::Map<self::test2::N1, self::test2::N1> m2 = block {
+    final core::Map<self::test2::N1, self::test2::N1> #t83 = <self::test2::N1, self::test2::N1>{};
+    final core::Map<self::test2::N1, self::test2::N1>? #t84 = let final self::test2::N1 #t85 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+    if(!(#t84 == null))
+      for (final core::MapEntry<self::test2::N1, self::test2::N1> #t86 in #t84{core::Map<self::test2::N1, self::test2::N1>}.{core::Map::entries}{core::Iterable<core::MapEntry<self::test2::N1, self::test2::N1>>})
+        #t83.{core::Map::[]=}{Invariant}(#t86.{core::MapEntry::key}{self::test2::N1}, #t86.{core::MapEntry::value}{self::test2::N1}){(self::test2::N1, self::test2::N1) → void};
+    #t83.{core::Map::[]=}{Invariant}(let final self::test2::N1 #t87 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."), let final self::test2::N1 #t88 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(self::test2::N1, self::test2::N1) → void};
+  } =>#t83;
+  core::Map<dynamic, dynamic> m3 = <dynamic, dynamic>{invalid-expression "pkg/front_end/testcases/nnbd/issue42758.dart:42:16: Error: Can't spread a value with static type 'N2'.
+  var m3 = {...n2, n1: n1};
+               ^": null, let final self::test2::N1 #t89 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."): let final self::test2::N1 #t90 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")};
+  core::Map<self::test2::N1, self::test2::N1> m4 = block {
+    final core::Map<self::test2::N1, self::test2::N1> #t91 = <self::test2::N1, self::test2::N1>{};
+    final core::Map<self::test2::N1, self::test2::N1>? #t92 = n2;
+    if(!(#t92 == null))
+      for (final core::MapEntry<self::test2::N1, self::test2::N1> #t93 in #t92{core::Map<self::test2::N1, self::test2::N1>}.{core::Map::entries}{core::Iterable<core::MapEntry<self::test2::N1, self::test2::N1>>})
+        #t91.{core::Map::[]=}{Invariant}(#t93.{core::MapEntry::key}{self::test2::N1}, #t93.{core::MapEntry::value}{self::test2::N1}){(self::test2::N1, self::test2::N1) → void};
+    #t91.{core::Map::[]=}{Invariant}(let final self::test2::N1 #t94 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."), let final self::test2::N1 #t95 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(self::test2::N1, self::test2::N1) → void};
+  } =>#t91;
+  core::Map<dynamic, dynamic> m5 = <dynamic, dynamic>{invalid-expression "pkg/front_end/testcases/nnbd/issue42758.dart:44:16: Error: Can't spread a value with static type 'N3'.
+  var m5 = {...n3, n1: n1};
+               ^": null, let final self::test2::N1 #t96 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."): let final self::test2::N1 #t97 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")};
+  core::Map<self::test2::N1, self::test2::N1> m6 = block {
+    final core::Map<self::test2::N1, self::test2::N1> #t98 = <self::test2::N1, self::test2::N1>{};
+    final core::Map<self::test2::N1, self::test2::N1>? #t99 = n3;
+    if(!(#t99 == null))
+      for (final core::MapEntry<self::test2::N1, self::test2::N1> #t100 in #t99{core::Map<self::test2::N1, self::test2::N1>}.{core::Map::entries}{core::Iterable<core::MapEntry<self::test2::N1, self::test2::N1>>})
+        #t98.{core::Map::[]=}{Invariant}(#t100.{core::MapEntry::key}{self::test2::N1}, #t100.{core::MapEntry::value}{self::test2::N1}){(self::test2::N1, self::test2::N1) → void};
+    #t98.{core::Map::[]=}{Invariant}(let final self::test2::N1 #t101 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."), let final self::test2::N1 #t102 = n1 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){(self::test2::N1, self::test2::N1) → void};
+  } =>#t98;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue42844_1.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42844_1.dart.weak.modular.expect
new file mode 100644
index 0000000..2637180
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42844_1.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue42844_1.dart:6:9: Error: Field 'n' should be initialized because its type 'Never' doesn't allow null.
+//   Never n; // Error.
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field Never n = null;
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  static factory •(Never n) → self::C
+    return new self::D::•(n);
+}
+class D extends core::Object implements self::C {
+  field Never n;
+  constructor •(Never n) → self::D
+    : self::D::n = n, super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::C::•
+}
diff --git a/pkg/front_end/testcases/nnbd/issue42844_2.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42844_2.dart.weak.modular.expect
new file mode 100644
index 0000000..d84e75e
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42844_2.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue42844_2.dart:6:17: Error: Final field 'n' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final dynamic n; // Error.
+//                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  final field dynamic n = null;
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  static factory •(dynamic n) → self::C
+    return new self::D::•(n);
+}
+class D extends core::Object implements self::C {
+  final field dynamic n;
+  constructor •(dynamic n) → self::D
+    : self::D::n = n, super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::C::•
+}
diff --git a/pkg/front_end/testcases/nnbd/issue42967.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue42967.dart.weak.modular.expect
new file mode 100644
index 0000000..3995dbf
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue42967.dart.weak.modular.expect
@@ -0,0 +1,86 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue42967.dart:7:7: Error: Field 'fieldNonNullableOfA' should be initialized because its type 'num' doesn't allow null.
+//   num fieldNonNullableOfA; // Error.
+//       ^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue42967.dart:10:17: Error: Final field 'fieldFinalDynamicOfA' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final dynamic fieldFinalDynamicOfA; // Error.
+//                 ^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue42967.dart:26:7: Error: Field 'fieldNonNullableOfB' should be initialized because its type 'num' doesn't allow null.
+//   num fieldNonNullableOfB; // Error.
+//       ^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue42967.dart:29:17: Error: Final field 'fieldFinalDynamicOfB' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final dynamic fieldFinalDynamicOfB; // Error.
+//                 ^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue42967.dart:45:7: Error: Field 'fieldNonNullableOfM' should be initialized because its type 'num' doesn't allow null.
+//   num fieldNonNullableOfM; // Error.
+//       ^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue42967.dart:50:17: Error: Final field 'fieldFinalDynamicOfM' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final dynamic fieldFinalDynamicOfM; // Error.
+//                 ^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::num fieldNonNullableOfA = null;
+  late field core::num fieldLateNonNullableOfA;
+  final field dynamic fieldFinalDynamicOfA = null;
+  late final [setter] field dynamic fieldLateFinalDynamicOfA;
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+abstract class AbstractA extends core::Object {
+  synthetic constructor •() → self::AbstractA
+    : super core::Object::•()
+    ;
+  external get fieldExternalNonNullableOfAbstractA() → core::num;
+  external set fieldExternalNonNullableOfAbstractA(core::num #externalFieldValue) → void;
+  abstract get fieldAbstractNonNullableOfAbstractA() → core::num;
+  abstract set fieldAbstractNonNullableOfAbstractA(core::num #externalFieldValue) → void;
+  external get fieldExternalFinalDynamicOfAbstractA() → dynamic;
+  abstract get fieldAbstractFinalDynamicOfAbstractA() → dynamic;
+}
+class B extends core::Object {
+  field core::num fieldNonNullableOfB = null;
+  late field core::num fieldLateNonNullableOfB;
+  final field dynamic fieldFinalDynamicOfB = null;
+  late final [setter] field dynamic fieldLateFinalDynamicOfB;
+  static factory •() → self::B
+    return throw 42;
+}
+abstract class AbstractB extends core::Object {
+  synthetic constructor •() → self::AbstractB
+    : super core::Object::•()
+    ;
+  external get fieldExternalNonNullableOfAbstractB() → core::num;
+  external set fieldExternalNonNullableOfAbstractB(core::num #externalFieldValue) → void;
+  abstract get fieldAbstractNonNullableOfAbstractB() → core::num;
+  abstract set fieldAbstractNonNullableOfAbstractB(core::num #externalFieldValue) → void;
+  external get fieldExternalFinalDynamicOfAbstractB() → dynamic;
+  abstract get fieldAbstractFinalDynamicOfAbstractB() → dynamic;
+}
+abstract class M extends core::Object /*isMixinDeclaration*/  {
+  field core::num fieldNonNullableOfM = null;
+  late field core::num fieldLateNonNullableOfM;
+  final field dynamic fieldFinalDynamicOfM = null;
+  late final [setter] field dynamic fieldLateFinalDynamicOfM;
+  external get fieldExternalNonNullableOfM() → core::num;
+  external set fieldExternalNonNullableOfM(core::num #externalFieldValue) → void;
+  abstract get fieldAbstractNonNullableOfM() → core::num;
+  abstract set fieldAbstractNonNullableOfM(core::num #externalFieldValue) → void;
+  external get fieldExternalFinalDynamicOfM() → dynamic;
+  abstract get fieldAbstractFinalDynamicOfM() → dynamic;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue43174.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue43174.dart.weak.modular.expect
new file mode 100644
index 0000000..2bc396c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue43174.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue43174.dart:17:12: Error: Can't return a value from a void function.
+//     return 42; // error
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+static method method(() → void f) → dynamic {
+  f(){() → void};
+}
+static method method2(() → FutureOr<void>f) → dynamic {
+  f(){() → FutureOr<void>};
+}
+static method test() → dynamic {
+  self::method(() → void {
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue43174.dart:17:12: Error: Can't return a value from a void function.
+    return 42; // error
+           ^" in 42;
+  });
+  self::method2(() → core::int {
+    return 42;
+  });
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue43211.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue43211.dart.weak.modular.expect
new file mode 100644
index 0000000..46f6782
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue43211.dart.weak.modular.expect
@@ -0,0 +1,265 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:10:53: Error: Type argument 'A<Null>' doesn't conform to the bound 'A<X>?' of the type variable 'X' on 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   void method1<Y extends A<Y>?>(A<Y> a, A<A<Null>>? b) {
+//                                                     ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>?> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:15:39: Error: Type argument 'Y' doesn't conform to the bound 'num' of the type variable 'X' on 'D'.
+// Try changing type arguments so that they conform to the bounds.
+//   void method2<Y extends String>(D<Y> a, D<String>? b) {
+//                                       ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:7:9: Context: This is the type variable whose bound isn't conformed to.
+// class D<X extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:15:53: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'D'.
+// Try changing type arguments so that they conform to the bounds.
+//   void method2<Y extends String>(D<Y> a, D<String>? b) {
+//                                                     ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:7:9: Context: This is the type variable whose bound isn't conformed to.
+// class D<X extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:21:39: Error: Type argument 'X/*1*/' doesn't conform to the bound 'A<X/*2*/>?' of the type variable 'X' on 'A'.
+//  - 'X/*1*/' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+//  - 'X/*2*/' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// extension ext2<X extends A<Null>?> on A<X> {}
+//                                       ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>?> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:23:7: Error: Type argument 'X/*1*/' doesn't conform to the bound 'A<X/*2*/>?' of the type variable 'X' on 'A' in the supertype 'A' of class 'B'.
+//  - 'X/*1*/' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+//  - 'X/*2*/' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// class B<X extends A<Null>?> implements A<X> {
+//       ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>?> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:24:41: Error: Type argument 'Y' doesn't conform to the bound 'A<X>?' of the type variable 'X' on 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   void method1<Y extends A<Null>?>(A<Y> a, A<A<Null>>? b) {
+//                                         ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>?> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:24:56: Error: Type argument 'A<Null>' doesn't conform to the bound 'A<X>?' of the type variable 'X' on 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   void method1<Y extends A<Null>?>(A<Y> a, A<A<Null>>? b) {
+//                                                        ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>?> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:29:39: Error: Type argument 'Y' doesn't conform to the bound 'num' of the type variable 'X' on 'D'.
+// Try changing type arguments so that they conform to the bounds.
+//   void method2<Y extends String>(D<Y> a, D<String>? b) {
+//                                       ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:7:9: Context: This is the type variable whose bound isn't conformed to.
+// class D<X extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:29:53: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'D'.
+// Try changing type arguments so that they conform to the bounds.
+//   void method2<Y extends String>(D<Y> a, D<String>? b) {
+//                                                     ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:7:9: Context: This is the type variable whose bound isn't conformed to.
+// class D<X extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:36:34: Error: Type argument 'A<Null>' doesn't conform to the bound 'A<X>?' of the type variable 'X' on 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   factory C.redirect(A<A<Null>>? a) = C.internal;
+//                                  ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>?> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:38:30: Error: Type argument 'A<Null>' doesn't conform to the bound 'A<X>?' of the type variable 'X' on 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   factory C.fact(A<A<Null>>? a) {
+//                              ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>?> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:12:17: Error: Type argument 'A<Null>' doesn't conform to the bound 'A<X>?' of the type variable 'X' on 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//     A<A<Null>>? d;
+//                 ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>?> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:16:11: Error: Type argument 'Y' doesn't conform to the bound 'num' of the type variable 'X' on 'D'.
+// Try changing type arguments so that they conform to the bounds.
+//     D<Y>? c;
+//           ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:7:9: Context: This is the type variable whose bound isn't conformed to.
+// class D<X extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:17:16: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'D'.
+// Try changing type arguments so that they conform to the bounds.
+//     D<String>? d;
+//                ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:7:9: Context: This is the type variable whose bound isn't conformed to.
+// class D<X extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:25:11: Error: Type argument 'Y' doesn't conform to the bound 'A<X>?' of the type variable 'X' on 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//     A<Y>? c;
+//           ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>?> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:26:17: Error: Type argument 'A<Null>' doesn't conform to the bound 'A<X>?' of the type variable 'X' on 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//     A<A<Null>>? d;
+//                 ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>?> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:30:11: Error: Type argument 'Y' doesn't conform to the bound 'num' of the type variable 'X' on 'D'.
+// Try changing type arguments so that they conform to the bounds.
+//     D<Y>? c;
+//           ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:7:9: Context: This is the type variable whose bound isn't conformed to.
+// class D<X extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:31:16: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'D'.
+// Try changing type arguments so that they conform to the bounds.
+//     D<String>? d;
+//                ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:7:9: Context: This is the type variable whose bound isn't conformed to.
+// class D<X extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:39:17: Error: Type argument 'A<Null>' doesn't conform to the bound 'A<X>?' of the type variable 'X' on 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//     A<A<Null>>? b;
+//                 ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>?> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:40:16: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'D'.
+// Try changing type arguments so that they conform to the bounds.
+//     D<String>? c;
+//                ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:7:9: Context: This is the type variable whose bound isn't conformed to.
+// class D<X extends num> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:45:17: Error: Type argument 'A<Null>' doesn't conform to the bound 'A<X>?' of the type variable 'X' on 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue43211.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//     A<A<Null>>? a;
+//                 ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>?> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43211.dart:46:16: Error: Type argument 'String' doesn't conform to the bound 'num' of the type variable 'X' on 'D'.
+// Try changing type arguments so that they conform to the bounds.
+//     D<String>? b;
+//                ^
+// pkg/front_end/testcases/nnbd/issue43211.dart:7:9: Context: This is the type variable whose bound isn't conformed to.
+// class D<X extends num> {}
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<X extends self::A<self::A::X%>? = self::A<dynamic>?> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+}
+class D<X extends core::num> extends core::Object {
+  synthetic constructor •() → self::D<self::D::X>
+    : super core::Object::•()
+    ;
+}
+class B<X extends self::A<Null>?> extends core::Object implements self::A<self::B::X%> {
+  synthetic constructor •() → self::B<self::B::X%>
+    : super core::Object::•()
+    ;
+  method method1<Y extends self::A<Null>?>(self::A<self::B::method1::Y%> a, self::A<self::A<Null>>? b) → void {
+    self::A<self::B::method1::Y%>? c;
+    self::A<self::A<Null>>? d;
+  }
+  method method2<Y extends core::String>(self::D<self::B::method2::Y> a, self::D<core::String>? b) → void {
+    self::D<self::B::method2::Y>? c;
+    self::D<core::String>? d;
+  }
+}
+class C extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor internal(dynamic _) → self::C
+    : super core::Object::•() {
+    self::A<self::A<Null>>? a;
+    self::D<core::String>? b;
+  }
+  static factory redirect(self::A<self::A<Null>>? a) → self::C
+    return new self::C::internal(a);
+  static factory fact(self::A<self::A<Null>>? a) → self::C {
+    self::A<self::A<Null>>? b;
+    self::D<core::String>? c;
+    return new self::C::internal(a);
+  }
+}
+extension Extension1<X extends self::A<X%>? = self::A<dynamic>?> on self::A<X%> {
+  method method1 = self::Extension1|method1;
+  tearoff method1 = self::Extension1|get#method1;
+  method method2 = self::Extension1|method2;
+  tearoff method2 = self::Extension1|get#method2;
+}
+extension ext2<X extends self::A<Null>?> on self::A<X%> {
+}
+static method Extension1|method1<X extends self::A<self::Extension1|method1::X%>? = self::A<dynamic>?, Y extends self::A<self::Extension1|method1::Y%>? = self::A<dynamic>?>(lowered final self::A<self::Extension1|method1::X%> #this, self::A<self::Extension1|method1::Y%> a, self::A<self::A<Null>>? b) → void {
+  self::A<self::Extension1|method1::Y%>? c;
+  self::A<self::A<Null>>? d;
+}
+static method Extension1|get#method1<X extends self::A<self::Extension1|get#method1::X%>? = self::A<dynamic>?>(lowered final self::A<self::Extension1|get#method1::X%> #this) → <Y extends self::A<Y%>? = self::A<dynamic>?>(self::A<Y%>, self::A<self::A<Null>>?) → void
+  return <Y extends self::A<Y%>? = self::A<dynamic>?>(self::A<Y%> a, self::A<self::A<Null>>? b) → void => self::Extension1|method1<self::Extension1|get#method1::X%, Y%>(#this, a, b);
+static method Extension1|method2<X extends self::A<self::Extension1|method2::X%>? = self::A<dynamic>?, Y extends core::String>(lowered final self::A<self::Extension1|method2::X%> #this, self::D<self::Extension1|method2::Y> a, self::D<core::String>? b) → void {
+  self::D<self::Extension1|method2::Y>? c;
+  self::D<core::String>? d;
+}
+static method Extension1|get#method2<X extends self::A<self::Extension1|get#method2::X%>? = self::A<dynamic>?>(lowered final self::A<self::Extension1|get#method2::X%> #this) → <Y extends core::String>(self::D<Y>, self::D<core::String>?) → void
+  return <Y extends core::String>(self::D<Y> a, self::D<core::String>? b) → void => self::Extension1|method2<self::Extension1|get#method2::X%, Y>(#this, a, b);
+static method test() → dynamic {
+  self::A<Null> a = new self::A::•<Null>();
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::C::redirect
+}
diff --git a/pkg/front_end/testcases/nnbd/issue43256.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue43256.dart.weak.modular.expect
new file mode 100644
index 0000000..097a586
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue43256.dart.weak.modular.expect
@@ -0,0 +1,142 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue43256.dart:16:17: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//   if (i > 0) ...nullableMap, // error
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/issue43256.dart:23:17: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//   if (i > 0) ...nullableList, // error
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/issue43256.dart:29:17: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//   if (i > 0) ...nullableList, // error
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/issue43256.dart:37:19: Error: Unexpected type 'X' of a map spread entry.  Expected 'dynamic' or a Map.
+//     if (i > 0) ...x, // error
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue43256.dart:38:19: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     if (i > 0) ...y, // error
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue43256.dart:48:19: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     if (i > 0) ...x, // error
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue43256.dart:48:19: Error: Unexpected type 'X' of a spread.  Expected 'dynamic' or an Iterable.
+//     if (i > 0) ...x, // error
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue43256.dart:49:19: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     if (i > 0) ...y, // error
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue43256.dart:53:19: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     if (i > 0) ...x, // error
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue43256.dart:53:19: Error: Unexpected type 'X' of a spread.  Expected 'dynamic' or an Iterable.
+//     if (i > 0) ...x, // error
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue43256.dart:54:19: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     if (i > 0) ...y, // error
+//                   ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+static field core::int i = 1;
+static field core::Map<core::int, core::String>? nullableMap = <core::int, core::String>{1: "Let", 2: "it", 3: "be"};
+static field core::List<core::int>? nullableList = <core::int>[1, 2, 3];
+static field dynamic dynamicMap = <core::int, core::String>{1: "Let", 2: "it", 3: "be"};
+static field dynamic dynamicList = <core::int>[1, 2, 3];
+static field core::Map<dynamic, dynamic> map1 = block {
+  final core::Map<dynamic, dynamic> #t1 = <dynamic, dynamic>{};
+  if(self::i.{core::num::>}(0){(core::num) → core::bool})
+    #t1.{core::Map::[]=}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43256.dart:16:17: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+  if (i > 0) ...nullableMap, // error
+                ^", null){(dynamic, dynamic) → void};
+  if(self::i.{core::num::>}(0){(core::num) → core::bool})
+    for (final core::MapEntry<dynamic, dynamic> #t2 in (self::dynamicMap as{TypeError,ForDynamic,ForNonNullableByDefault} core::Map<dynamic, dynamic>).{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, dynamic>>})
+      #t1.{core::Map::[]=}{Invariant}(#t2.{core::MapEntry::key}{dynamic}, #t2.{core::MapEntry::value}{dynamic}){(dynamic, dynamic) → void};
+  if(self::i.{core::num::>}(0){(core::num) → core::bool})
+    for (final core::MapEntry<dynamic, dynamic> #t3 in self::nullableMap!.{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, dynamic>>})
+      #t1.{core::Map::[]=}{Invariant}(#t3.{core::MapEntry::key}{dynamic}, #t3.{core::MapEntry::value}{dynamic}){(dynamic, dynamic) → void};
+} =>#t1;
+static field core::Set<dynamic> set1 = block {
+  final core::Set<dynamic> #t4 = col::LinkedHashSet::•<dynamic>();
+  #t4.{core::Set::add}{Invariant}(0){(dynamic) → core::bool};
+  if(self::i.{core::num::>}(0){(core::num) → core::bool})
+    #t4.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43256.dart:23:17: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+  if (i > 0) ...nullableList, // error
+                ^"){(dynamic) → core::bool};
+  if(self::i.{core::num::>}(0){(core::num) → core::bool})
+    #t4.{core::Set::addAll}{Invariant}(self::dynamicList as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>){(core::Iterable<dynamic>) → void};
+  if(self::i.{core::num::>}(0){(core::num) → core::bool})
+    #t4.{core::Set::addAll}{Invariant}(self::nullableList!){(core::Iterable<dynamic>) → void};
+} =>#t4;
+static field core::List<dynamic> list1 = block {
+  final core::List<dynamic> #t5 = <dynamic>[];
+  if(self::i.{core::num::>}(0){(core::num) → core::bool})
+    #t5.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43256.dart:29:17: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+  if (i > 0) ...nullableList, // error
+                ^"){(dynamic) → void};
+  if(self::i.{core::num::>}(0){(core::num) → core::bool})
+    #t5.{core::List::addAll}{Invariant}(self::dynamicList as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>){(core::Iterable<dynamic>) → void};
+  if(self::i.{core::num::>}(0){(core::num) → core::bool})
+    #t5.{core::List::addAll}{Invariant}(self::nullableList!){(core::Iterable<dynamic>) → void};
+} =>#t5;
+static method testMap<X extends dynamic, Y extends core::Map<core::int, core::String>?, Z extends core::Map<core::int, core::String>>(self::testMap::X% x, self::testMap::Y% y, self::testMap::Z z) → dynamic {
+  core::Map<dynamic, dynamic> map2 = block {
+    final core::Map<dynamic, dynamic> #t6 = <dynamic, dynamic>{};
+    if(self::i.{core::num::>}(0){(core::num) → core::bool})
+      #t6.{core::Map::[]=}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43256.dart:37:19: Error: Unexpected type 'X' of a map spread entry.  Expected 'dynamic' or a Map.
+    if (i > 0) ...x, // error
+                  ^", null){(dynamic, dynamic) → void};
+    if(self::i.{core::num::>}(0){(core::num) → core::bool})
+      #t6.{core::Map::[]=}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43256.dart:38:19: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    if (i > 0) ...y, // error
+                  ^", null){(dynamic, dynamic) → void};
+    if(self::i.{core::num::>}(0){(core::num) → core::bool})
+      for (final core::MapEntry<dynamic, dynamic> #t7 in z.{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, dynamic>>})
+        #t6.{core::Map::[]=}{Invariant}(#t7.{core::MapEntry::key}{dynamic}, #t7.{core::MapEntry::value}{dynamic}){(dynamic, dynamic) → void};
+    if(self::i.{core::num::>}(0){(core::num) → core::bool})
+      for (final core::MapEntry<dynamic, dynamic> #t8 in y!.{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, dynamic>>})
+        #t6.{core::Map::[]=}{Invariant}(#t8.{core::MapEntry::key}{dynamic}, #t8.{core::MapEntry::value}{dynamic}){(dynamic, dynamic) → void};
+  } =>#t6;
+}
+static method testIterables<X extends dynamic, Y extends core::List<core::int>?, Z extends core::List<core::int>>(self::testIterables::X% x, self::testIterables::Y% y, self::testIterables::Z z) → dynamic {
+  core::Set<dynamic> set2 = block {
+    final core::Set<dynamic> #t9 = col::LinkedHashSet::•<dynamic>();
+    #t9.{core::Set::add}{Invariant}(0){(dynamic) → core::bool};
+    if(self::i.{core::num::>}(0){(core::num) → core::bool})
+      #t9.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43256.dart:48:19: Error: Unexpected type 'X' of a spread.  Expected 'dynamic' or an Iterable.
+    if (i > 0) ...x, // error
+                  ^"){(dynamic) → core::bool};
+    if(self::i.{core::num::>}(0){(core::num) → core::bool})
+      #t9.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43256.dart:49:19: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    if (i > 0) ...y, // error
+                  ^"){(dynamic) → core::bool};
+    if(self::i.{core::num::>}(0){(core::num) → core::bool})
+      #t9.{core::Set::addAll}{Invariant}(z){(core::Iterable<dynamic>) → void};
+  } =>#t9;
+  core::List<dynamic> list2 = block {
+    final core::List<dynamic> #t10 = <dynamic>[];
+    if(self::i.{core::num::>}(0){(core::num) → core::bool})
+      #t10.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43256.dart:53:19: Error: Unexpected type 'X' of a spread.  Expected 'dynamic' or an Iterable.
+    if (i > 0) ...x, // error
+                  ^"){(dynamic) → void};
+    if(self::i.{core::num::>}(0){(core::num) → core::bool})
+      #t10.{core::List::add}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43256.dart:54:19: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    if (i > 0) ...y, // error
+                  ^"){(dynamic) → void};
+    if(self::i.{core::num::>}(0){(core::num) → core::bool})
+      #t10.{core::List::addAll}{Invariant}(z){(core::Iterable<dynamic>) → void};
+  } =>#t10;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue43276.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue43276.dart.weak.modular.expect
new file mode 100644
index 0000000..6fe128e
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue43276.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue43276.dart:6:14: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   C.gen({int i}); // error
+//              ^
+//
+// pkg/front_end/testcases/nnbd/issue43276.dart:8:23: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   factory C.fact({int i}) /* error */ {
+//                       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor gen({core::int i = #C2}) → self::C
+    : super core::Object::•()
+    ;
+  static factory fact({core::int i = #C2}) → self::C {
+    return new self::C::gen();
+  }
+  static factory redirect({core::int i = #C2}) → self::C
+    return new self::C::gen(i: i);
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::C::redirect
+  #C2 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/issue43278.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue43278.dart.weak.modular.expect
new file mode 100644
index 0000000..c69ecec
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue43278.dart.weak.modular.expect
@@ -0,0 +1,91 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue43278.dart:13:5: Error: Property 'foo' cannot be accessed on 'A?' because it is potentially null.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/issue43278.dart'.
+// Try accessing using ?. instead.
+//   a.foo ??= x; // Error.
+//     ^^^
+//
+// pkg/front_end/testcases/nnbd/issue43278.dart:14:5: Error: Property 'foo' cannot be accessed on 'T' because it is potentially null.
+// Try accessing using ?. instead.
+//   t.foo ??= x; // Error.
+//     ^^^
+//
+// pkg/front_end/testcases/nnbd/issue43278.dart:28:5: Error: Property 'fooExtension' cannot be accessed on 'B?' because it is potentially null.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/issue43278.dart'.
+// Try accessing using ?. instead.
+//   b.fooExtension ??= x; // Error.
+//     ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/issue43278.dart:29:5: Error: Property 'fooExtension' cannot be accessed on 'T' because it is potentially null.
+// Try accessing using ?. instead.
+//   t.fooExtension ??= x; // Error.
+//     ^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int? foo = null;
+  field self::A bar;
+  constructor •(self::A bar) → self::A
+    : self::A::bar = bar, super core::Object::•()
+    ;
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+}
+extension Extension on self::B {
+  get fooExtension = self::Extension|get#fooExtension;
+  get barExtension = self::Extension|get#barExtension;
+  set fooExtension = self::Extension|set#fooExtension;
+}
+static method test<T extends self::A?>(self::A? a, self::test::T% t, dynamic d, core::int x) → dynamic {
+  let final self::A? #t1 = a in invalid-expression "pkg/front_end/testcases/nnbd/issue43278.dart:13:5: Error: Property 'foo' cannot be accessed on 'A?' because it is potentially null.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/issue43278.dart'.
+Try accessing using ?. instead.
+  a.foo ??= x; // Error.
+    ^^^" in #t1.{self::A::foo}{<nullable>}.{core::int?} == null ?{core::int} invalid-expression "pkg/front_end/testcases/nnbd/issue43278.dart:13:5: Error: Property 'foo' cannot be accessed on 'A?' because it is potentially null.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/issue43278.dart'.
+Try accessing using ?. instead.
+  a.foo ??= x; // Error.
+    ^^^" in #t1.{self::A::foo}{<nullable>}. = x : null;
+  let final self::test::T% #t2 = t in invalid-expression "pkg/front_end/testcases/nnbd/issue43278.dart:14:5: Error: Property 'foo' cannot be accessed on 'T' because it is potentially null.
+Try accessing using ?. instead.
+  t.foo ??= x; // Error.
+    ^^^" in #t2.{self::A::foo}{<nullable>}.{core::int?} == null ?{core::int} invalid-expression "pkg/front_end/testcases/nnbd/issue43278.dart:14:5: Error: Property 'foo' cannot be accessed on 'T' because it is potentially null.
+Try accessing using ?. instead.
+  t.foo ??= x; // Error.
+    ^^^" in #t2.{self::A::foo}{<nullable>}. = x : null;
+  let final dynamic #t3 = d in #t3{dynamic}.foo == null ?{dynamic} #t3{dynamic}.foo = x : null;
+  let final self::A? #t4 = a in #t4 == null ?{core::int?} null : let final self::A #t5 = #t4{self::A}.{self::A::bar}{self::A} in #t5.{self::A::foo}{core::int?} == null ?{core::int} #t5.{self::A::foo} = x : null;
+}
+static method Extension|get#fooExtension(lowered final self::B #this) → core::int?
+  return null;
+static method Extension|set#fooExtension(lowered final self::B #this, core::int? value) → void {}
+static method Extension|get#barExtension(lowered final self::B #this) → self::B
+  return new self::B::•();
+static method testExtension<T extends self::B?>(self::B? b, self::testExtension::T% t, core::int x) → dynamic {
+  let final self::B? #t6 = b in invalid-expression "pkg/front_end/testcases/nnbd/issue43278.dart:28:5: Error: Property 'fooExtension' cannot be accessed on 'B?' because it is potentially null.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/issue43278.dart'.
+Try accessing using ?. instead.
+  b.fooExtension ??= x; // Error.
+    ^^^^^^^^^^^^" in self::Extension|get#fooExtension(#t6) == null ?{core::int} invalid-expression "pkg/front_end/testcases/nnbd/issue43278.dart:28:5: Error: Property 'fooExtension' cannot be accessed on 'B?' because it is potentially null.
+ - 'B' is from 'pkg/front_end/testcases/nnbd/issue43278.dart'.
+Try accessing using ?. instead.
+  b.fooExtension ??= x; // Error.
+    ^^^^^^^^^^^^" in self::Extension|set#fooExtension(#t6, x) : null;
+  let final self::testExtension::T% #t7 = t in invalid-expression "pkg/front_end/testcases/nnbd/issue43278.dart:29:5: Error: Property 'fooExtension' cannot be accessed on 'T' because it is potentially null.
+Try accessing using ?. instead.
+  t.fooExtension ??= x; // Error.
+    ^^^^^^^^^^^^" in self::Extension|get#fooExtension(#t7) == null ?{core::int} invalid-expression "pkg/front_end/testcases/nnbd/issue43278.dart:29:5: Error: Property 'fooExtension' cannot be accessed on 'T' because it is potentially null.
+Try accessing using ?. instead.
+  t.fooExtension ??= x; // Error.
+    ^^^^^^^^^^^^" in self::Extension|set#fooExtension(#t7, x) : null;
+  let final self::B? #t8 = b in #t8 == null ?{core::int?} null : let final self::B #t9 = self::Extension|get#barExtension(#t8{self::B}) in self::Extension|get#fooExtension(#t9) == null ?{core::int} self::Extension|set#fooExtension(#t9, x) : null;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue43354.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue43354.dart.weak.modular.expect
new file mode 100644
index 0000000..b068885
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue43354.dart.weak.modular.expect
@@ -0,0 +1,82 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue43354.dart:8:18: Error: Can't have a late final field in a class with a const constructor.
+//   late final int foo = 42;
+//                  ^
+// pkg/front_end/testcases/nnbd/issue43354.dart:9:9: Context: This constructor is const.
+//   const A();
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43354.dart:13:18: Error: Can't have a late final field in a class with a const constructor.
+//   late final int foo = 42;
+//                  ^
+// pkg/front_end/testcases/nnbd/issue43354.dart:15:9: Context: This constructor is const.
+//   const B();
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43354.dart:14:21: Error: Can't have a late final field in a class with a const constructor.
+//   late final String bar = "foobar";
+//                     ^
+// pkg/front_end/testcases/nnbd/issue43354.dart:15:9: Context: This constructor is const.
+//   const B();
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43354.dart:19:18: Error: Can't have a late final field in a class with a const constructor.
+//   late final int foo = 42;
+//                  ^
+// pkg/front_end/testcases/nnbd/issue43354.dart:20:9: Context: This constructor is const.
+//   const C();
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43354.dart:25:18: Error: Can't have a late final field in a class with a const constructor.
+//   late final int foo = 42;
+//                  ^
+// pkg/front_end/testcases/nnbd/issue43354.dart:27:9: Context: This constructor is const.
+//   const D();
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43354.dart:26:21: Error: Can't have a late final field in a class with a const constructor.
+//   late final String bar = "foobar";
+//                     ^
+// pkg/front_end/testcases/nnbd/issue43354.dart:27:9: Context: This constructor is const.
+//   const D();
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  late final field core::int foo = 42;
+  const constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class B extends core::Object /*hasConstConstructor*/  {
+  late final field core::int foo = 42;
+  late final field core::String bar = "foobar";
+  const constructor •() → self::B
+    : super core::Object::•()
+    ;
+}
+class C extends core::Object /*hasConstConstructor*/  {
+  late final field core::int foo = 42;
+  const constructor •() → self::C
+    : super core::Object::•()
+    ;
+  const constructor another() → self::C
+    : super core::Object::•()
+    ;
+}
+class D extends core::Object /*hasConstConstructor*/  {
+  late final field core::int foo = 42;
+  late final field core::String bar = "foobar";
+  const constructor •() → self::D
+    : super core::Object::•()
+    ;
+  const constructor another() → self::D
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue43455.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue43455.dart.weak.modular.expect
new file mode 100644
index 0000000..2815e55
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue43455.dart.weak.modular.expect
@@ -0,0 +1,66 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+class C<X extends core::Object?, Y extends core::Object> extends core::Object {
+  synthetic constructor •() → self::C<self::C::X%, self::C::Y>
+    : super core::Object::•()
+    ;
+  method test(covariant-by-class self::C::X% x, covariant-by-class self::C::Y? y) → dynamic {
+    core::Set<core::Object?> v = block {
+      final core::Set<core::Object?> #t1 = col::LinkedHashSet::•<core::Object?>();
+      #t1.{core::Set::add}{Invariant}(x){(core::Object?) → core::bool};
+      #t1.{core::Set::add}{Invariant}(42){(core::Object?) → core::bool};
+    } =>#t1;
+    core::Set<core::Object?> w = block {
+      final core::Set<core::Object?> #t2 = col::LinkedHashSet::•<core::Object?>();
+      #t2.{core::Set::add}{Invariant}(42){(core::Object?) → core::bool};
+      #t2.{core::Set::add}{Invariant}(x){(core::Object?) → core::bool};
+    } =>#t2;
+    core::Set<core::Object?> p = block {
+      final core::Set<core::Object?> #t3 = col::LinkedHashSet::•<core::Object?>();
+      #t3.{core::Set::add}{Invariant}(y){(core::Object?) → core::bool};
+      #t3.{core::Set::add}{Invariant}(42){(core::Object?) → core::bool};
+    } =>#t3;
+    core::Set<core::Object?> q = block {
+      final core::Set<core::Object?> #t4 = col::LinkedHashSet::•<core::Object?>();
+      #t4.{core::Set::add}{Invariant}(42){(core::Object?) → core::bool};
+      #t4.{core::Set::add}{Invariant}(y){(core::Object?) → core::bool};
+    } =>#t4;
+    self::assertRightSubtype(v);
+    self::assertLeftSubtype<core::Set<core::Object?>>(v);
+    self::assertRightSubtype(w);
+    self::assertLeftSubtype<core::Set<core::Object?>>(w);
+    self::assertRightSubtype(p);
+    self::assertLeftSubtype<core::Set<core::Object?>>(p);
+    self::assertRightSubtype(q);
+    self::assertLeftSubtype<core::Set<core::Object?>>(q);
+    if(x is{ForNonNullableByDefault} core::Object?) {
+      core::Set<core::Object?> v = block {
+        final core::Set<core::Object?> #t5 = col::LinkedHashSet::•<core::Object?>();
+        #t5.{core::Set::add}{Invariant}(x{self::C::X% & core::Object? /* '%' & '?' = '%' */}){(core::Object?) → core::bool};
+        #t5.{core::Set::add}{Invariant}(42){(core::Object?) → core::bool};
+      } =>#t5;
+      core::Set<core::Object?> w = block {
+        final core::Set<core::Object?> #t6 = col::LinkedHashSet::•<core::Object?>();
+        #t6.{core::Set::add}{Invariant}(42){(core::Object?) → core::bool};
+        #t6.{core::Set::add}{Invariant}(x{self::C::X% & core::Object? /* '%' & '?' = '%' */}){(core::Object?) → core::bool};
+      } =>#t6;
+      self::assertRightSubtype(v);
+      self::assertLeftSubtype<core::Set<core::Object?>>(v);
+      self::assertRightSubtype(w);
+      self::assertLeftSubtype<core::Set<core::Object?>>(w);
+    }
+  }
+}
+static method assertRightSubtype(dynamic x) → dynamic {
+  x as{ForNonNullableByDefault} core::Set<core::Object?>;
+}
+static method assertLeftSubtype<X extends core::Object? = dynamic>(self::assertLeftSubtype::X% x) → dynamic {
+  col::LinkedHashSet::•<core::Object?>() as{ForNonNullableByDefault} self::assertLeftSubtype::X%;
+}
+static method main() → dynamic {
+  new self::C::•<core::int?, core::int>().{self::C::test}(42, null){(core::int?, core::int?) → dynamic};
+  new self::C::•<core::int?, core::int>().{self::C::test}(null, null){(core::int?, core::int?) → dynamic};
+}
diff --git a/pkg/front_end/testcases/nnbd/issue43495.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue43495.dart.weak.modular.expect
new file mode 100644
index 0000000..e415041
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue43495.dart.weak.modular.expect
@@ -0,0 +1,731 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:8:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {...a}, // Error.
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:9:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {...b}, // Error.
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:10:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {...c}, // Error.
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:11:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {...d}, // Error.
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:12:19: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     <int, int>{...a}, // Error.
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:12:19: Error: Unexpected type 'List<int>?' of a map spread entry.  Expected 'dynamic' or a Map.
+//  - 'List' is from 'dart:core'.
+//     <int, int>{...a}, // Error.
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:13:14: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     <int>{...d}, // Error.
+//              ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:13:14: Error: Unexpected type 'Map<int, int>?' of a spread.  Expected 'dynamic' or an Iterable.
+//  - 'Map' is from 'dart:core'.
+//     <int>{...d}, // Error.
+//              ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:14:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {if (condition) ...a}, // Error.
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:15:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {if (condition) ...b}, // Error.
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:16:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {if (condition) ...c}, // Error.
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:17:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {if (condition) ...d}, // Error.
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:18:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (dynamic e in iterable) ...a}, // Error.
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:19:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (dynamic e in iterable) ...b}, // Error.
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:20:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (dynamic e in iterable) ...c}, // Error.
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:21:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (dynamic e in iterable) ...d}, // Error.
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:22:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (int i = 0; i < 42; ++i) ...a}, // Error.
+//                                      ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:23:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (int i = 0; i < 42; ++i) ...b}, // Error.
+//                                      ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:24:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (int i = 0; i < 42; ++i) ...c}, // Error.
+//                                      ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:25:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (int i = 0; i < 42; ++i) ...d}, // Error.
+//                                      ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:50:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {...x}, // Error.
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:51:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {...y}, // Error.
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:52:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {...z}, // Error.
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:53:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {...w}, // Error.
+//         ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:54:19: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     <int, int>{...x}, // Error.
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:54:19: Error: Unexpected type 'X' of a map spread entry.  Expected 'dynamic' or a Map.
+//     <int, int>{...x}, // Error.
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:55:14: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     <int>{...w}, // Error.
+//              ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:55:14: Error: Unexpected type 'W' of a spread.  Expected 'dynamic' or an Iterable.
+//     <int>{...w}, // Error.
+//              ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:56:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {if (condition) ...x}, // Error.
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:57:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {if (condition) ...y}, // Error.
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:58:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {if (condition) ...z}, // Error.
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:59:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {if (condition) ...w}, // Error.
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:60:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (dynamic e in iterable) ...x}, // Error.
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:61:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (dynamic e in iterable) ...y}, // Error.
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:62:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (dynamic e in iterable) ...z}, // Error.
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:63:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (dynamic e in iterable) ...w}, // Error.
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:64:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (int i = 0; i < 42; ++i) ...x}, // Error.
+//                                      ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:65:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (int i = 0; i < 42; ++i) ...y}, // Error.
+//                                      ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:66:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (int i = 0; i < 42; ++i) ...z}, // Error.
+//                                      ^
+//
+// pkg/front_end/testcases/nnbd/issue43495.dart:67:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+//     {for (int i = 0; i < 42; ++i) ...w}, // Error.
+//                                      ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+static method foo(core::bool condition, core::Iterable<dynamic> iterable, core::List<core::int>? a, core::Set<core::int>? b, core::Iterable<core::int>? c, core::Map<core::int, core::int>? d) → dynamic {
+  return <core::Object>[ block {
+    final core::Set<core::int> #t1 = col::LinkedHashSet::•<core::int>();
+    for (final dynamic #t2 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:8:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {...a}, // Error.
+        ^") {
+      final core::int #t3 = #t2 as{TypeError,ForNonNullableByDefault} core::int;
+      #t1.{core::Set::add}{Invariant}(#t3){(core::int) → core::bool};
+    }
+  } =>#t1, block {
+    final core::Set<core::int> #t4 = col::LinkedHashSet::•<core::int>();
+    for (final dynamic #t5 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:9:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {...b}, // Error.
+        ^") {
+      final core::int #t6 = #t5 as{TypeError,ForNonNullableByDefault} core::int;
+      #t4.{core::Set::add}{Invariant}(#t6){(core::int) → core::bool};
+    }
+  } =>#t4, block {
+    final core::Set<core::int> #t7 = col::LinkedHashSet::•<core::int>();
+    for (final dynamic #t8 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:10:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {...c}, // Error.
+        ^") {
+      final core::int #t9 = #t8 as{TypeError,ForNonNullableByDefault} core::int;
+      #t7.{core::Set::add}{Invariant}(#t9){(core::int) → core::bool};
+    }
+  } =>#t7, <core::int, core::int>{invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:11:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {...d}, // Error.
+        ^": null}, <core::int, core::int>{invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:12:19: Error: Unexpected type 'List<int>?' of a map spread entry.  Expected 'dynamic' or a Map.
+ - 'List' is from 'dart:core'.
+    <int, int>{...a}, // Error.
+                  ^": null}, block {
+    final core::Set<core::int> #t10 = col::LinkedHashSet::•<core::int>();
+    #t10.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:13:14: Error: Unexpected type 'Map<int, int>?' of a spread.  Expected 'dynamic' or an Iterable.
+ - 'Map' is from 'dart:core'.
+    <int>{...d}, // Error.
+             ^"){(core::int) → core::bool};
+  } =>#t10, block {
+    final core::Set<core::int> #t11 = col::LinkedHashSet::•<core::int>();
+    if(condition)
+      for (final dynamic #t12 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:14:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {if (condition) ...a}, // Error.
+                       ^") {
+        final core::int #t13 = #t12 as{TypeError,ForNonNullableByDefault} core::int;
+        #t11.{core::Set::add}{Invariant}(#t13){(core::int) → core::bool};
+      }
+  } =>#t11, block {
+    final core::Set<core::int> #t14 = col::LinkedHashSet::•<core::int>();
+    if(condition)
+      for (final dynamic #t15 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:15:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {if (condition) ...b}, // Error.
+                       ^") {
+        final core::int #t16 = #t15 as{TypeError,ForNonNullableByDefault} core::int;
+        #t14.{core::Set::add}{Invariant}(#t16){(core::int) → core::bool};
+      }
+  } =>#t14, block {
+    final core::Set<core::int> #t17 = col::LinkedHashSet::•<core::int>();
+    if(condition)
+      for (final dynamic #t18 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:16:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {if (condition) ...c}, // Error.
+                       ^") {
+        final core::int #t19 = #t18 as{TypeError,ForNonNullableByDefault} core::int;
+        #t17.{core::Set::add}{Invariant}(#t19){(core::int) → core::bool};
+      }
+  } =>#t17, block {
+    final core::Map<core::int, core::int> #t20 = <core::int, core::int>{};
+    if(condition)
+      #t20.{core::Map::[]=}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:17:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {if (condition) ...d}, // Error.
+                       ^", null){(core::int, core::int) → void};
+  } =>#t20, block {
+    final core::Set<core::int> #t21 = col::LinkedHashSet::•<core::int>();
+    for (dynamic e in iterable)
+      for (final dynamic #t22 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:18:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (dynamic e in iterable) ...a}, // Error.
+                                    ^") {
+        final core::int #t23 = #t22 as{TypeError,ForNonNullableByDefault} core::int;
+        #t21.{core::Set::add}{Invariant}(#t23){(core::int) → core::bool};
+      }
+  } =>#t21, block {
+    final core::Set<core::int> #t24 = col::LinkedHashSet::•<core::int>();
+    for (dynamic e in iterable)
+      for (final dynamic #t25 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:19:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (dynamic e in iterable) ...b}, // Error.
+                                    ^") {
+        final core::int #t26 = #t25 as{TypeError,ForNonNullableByDefault} core::int;
+        #t24.{core::Set::add}{Invariant}(#t26){(core::int) → core::bool};
+      }
+  } =>#t24, block {
+    final core::Set<core::int> #t27 = col::LinkedHashSet::•<core::int>();
+    for (dynamic e in iterable)
+      for (final dynamic #t28 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:20:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (dynamic e in iterable) ...c}, // Error.
+                                    ^") {
+        final core::int #t29 = #t28 as{TypeError,ForNonNullableByDefault} core::int;
+        #t27.{core::Set::add}{Invariant}(#t29){(core::int) → core::bool};
+      }
+  } =>#t27, block {
+    final core::Map<core::int, core::int> #t30 = <core::int, core::int>{};
+    for (dynamic e in iterable)
+      #t30.{core::Map::[]=}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:21:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (dynamic e in iterable) ...d}, // Error.
+                                    ^", null){(core::int, core::int) → void};
+  } =>#t30, block {
+    final core::Set<core::int> #t31 = col::LinkedHashSet::•<core::int>();
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int})
+      for (final dynamic #t32 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:22:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (int i = 0; i < 42; ++i) ...a}, // Error.
+                                     ^") {
+        final core::int #t33 = #t32 as{TypeError,ForNonNullableByDefault} core::int;
+        #t31.{core::Set::add}{Invariant}(#t33){(core::int) → core::bool};
+      }
+  } =>#t31, block {
+    final core::Set<core::int> #t34 = col::LinkedHashSet::•<core::int>();
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int})
+      for (final dynamic #t35 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:23:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (int i = 0; i < 42; ++i) ...b}, // Error.
+                                     ^") {
+        final core::int #t36 = #t35 as{TypeError,ForNonNullableByDefault} core::int;
+        #t34.{core::Set::add}{Invariant}(#t36){(core::int) → core::bool};
+      }
+  } =>#t34, block {
+    final core::Set<core::int> #t37 = col::LinkedHashSet::•<core::int>();
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int})
+      for (final dynamic #t38 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:24:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (int i = 0; i < 42; ++i) ...c}, // Error.
+                                     ^") {
+        final core::int #t39 = #t38 as{TypeError,ForNonNullableByDefault} core::int;
+        #t37.{core::Set::add}{Invariant}(#t39){(core::int) → core::bool};
+      }
+  } =>#t37, block {
+    final core::Map<core::int, core::int> #t40 = <core::int, core::int>{};
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int})
+      #t40.{core::Map::[]=}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:25:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (int i = 0; i < 42; ++i) ...d}, // Error.
+                                     ^", null){(core::int, core::int) → void};
+  } =>#t40, block {
+    final core::Set<core::int> #t41 = col::LinkedHashSet::•<core::int>();
+    final core::Iterable<dynamic>? #t42 = a;
+    if(!(#t42 == null))
+      for (final dynamic #t43 in #t42{core::Iterable<dynamic>}) {
+        final core::int #t44 = #t43 as{TypeError,ForNonNullableByDefault} core::int;
+        #t41.{core::Set::add}{Invariant}(#t44){(core::int) → core::bool};
+      }
+  } =>#t41, block {
+    final core::Set<core::int> #t45 = col::LinkedHashSet::•<core::int>();
+    final core::Iterable<dynamic>? #t46 = b;
+    if(!(#t46 == null))
+      for (final dynamic #t47 in #t46{core::Iterable<dynamic>}) {
+        final core::int #t48 = #t47 as{TypeError,ForNonNullableByDefault} core::int;
+        #t45.{core::Set::add}{Invariant}(#t48){(core::int) → core::bool};
+      }
+  } =>#t45, block {
+    final core::Set<core::int> #t49 = col::LinkedHashSet::•<core::int>();
+    final core::Iterable<dynamic>? #t50 = c;
+    if(!(#t50 == null))
+      for (final dynamic #t51 in #t50{core::Iterable<dynamic>}) {
+        final core::int #t52 = #t51 as{TypeError,ForNonNullableByDefault} core::int;
+        #t49.{core::Set::add}{Invariant}(#t52){(core::int) → core::bool};
+      }
+  } =>#t49, block {
+    final core::Map<core::int, core::int> #t53 = <core::int, core::int>{};
+    final core::Map<core::int, core::int>? #t54 = d;
+    if(!(#t54 == null))
+      for (final core::MapEntry<core::int, core::int> #t55 in #t54{core::Map<core::int, core::int>}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int, core::int>>})
+        #t53.{core::Map::[]=}{Invariant}(#t55.{core::MapEntry::key}{core::int}, #t55.{core::MapEntry::value}{core::int}){(core::int, core::int) → void};
+  } =>#t53, block {
+    final core::Set<core::int> #t56 = col::LinkedHashSet::•<core::int>();
+    if(condition) {
+      final core::Iterable<dynamic>? #t57 = a;
+      if(!(#t57 == null))
+        for (final dynamic #t58 in #t57{core::Iterable<dynamic>}) {
+          final core::int #t59 = #t58 as{TypeError,ForNonNullableByDefault} core::int;
+          #t56.{core::Set::add}{Invariant}(#t59){(core::int) → core::bool};
+        }
+    }
+  } =>#t56, block {
+    final core::Set<core::int> #t60 = col::LinkedHashSet::•<core::int>();
+    if(condition) {
+      final core::Iterable<dynamic>? #t61 = b;
+      if(!(#t61 == null))
+        for (final dynamic #t62 in #t61{core::Iterable<dynamic>}) {
+          final core::int #t63 = #t62 as{TypeError,ForNonNullableByDefault} core::int;
+          #t60.{core::Set::add}{Invariant}(#t63){(core::int) → core::bool};
+        }
+    }
+  } =>#t60, block {
+    final core::Set<core::int> #t64 = col::LinkedHashSet::•<core::int>();
+    if(condition) {
+      final core::Iterable<dynamic>? #t65 = c;
+      if(!(#t65 == null))
+        for (final dynamic #t66 in #t65{core::Iterable<dynamic>}) {
+          final core::int #t67 = #t66 as{TypeError,ForNonNullableByDefault} core::int;
+          #t64.{core::Set::add}{Invariant}(#t67){(core::int) → core::bool};
+        }
+    }
+  } =>#t64, block {
+    final core::Map<core::int, core::int> #t68 = <core::int, core::int>{};
+    if(condition) {
+      final core::Map<core::int, core::int>? #t69 = d;
+      if(!(#t69 == null))
+        for (final core::MapEntry<core::int, core::int> #t70 in #t69{core::Map<core::int, core::int>}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int, core::int>>})
+          #t68.{core::Map::[]=}{Invariant}(#t70.{core::MapEntry::key}{core::int}, #t70.{core::MapEntry::value}{core::int}){(core::int, core::int) → void};
+    }
+  } =>#t68, block {
+    final core::Set<core::int> #t71 = col::LinkedHashSet::•<core::int>();
+    for (dynamic e in iterable) {
+      final core::Iterable<dynamic>? #t72 = a;
+      if(!(#t72 == null))
+        for (final dynamic #t73 in #t72{core::Iterable<dynamic>}) {
+          final core::int #t74 = #t73 as{TypeError,ForNonNullableByDefault} core::int;
+          #t71.{core::Set::add}{Invariant}(#t74){(core::int) → core::bool};
+        }
+    }
+  } =>#t71, block {
+    final core::Set<core::int> #t75 = col::LinkedHashSet::•<core::int>();
+    for (dynamic e in iterable) {
+      final core::Iterable<dynamic>? #t76 = b;
+      if(!(#t76 == null))
+        for (final dynamic #t77 in #t76{core::Iterable<dynamic>}) {
+          final core::int #t78 = #t77 as{TypeError,ForNonNullableByDefault} core::int;
+          #t75.{core::Set::add}{Invariant}(#t78){(core::int) → core::bool};
+        }
+    }
+  } =>#t75, block {
+    final core::Set<core::int> #t79 = col::LinkedHashSet::•<core::int>();
+    for (dynamic e in iterable) {
+      final core::Iterable<dynamic>? #t80 = c;
+      if(!(#t80 == null))
+        for (final dynamic #t81 in #t80{core::Iterable<dynamic>}) {
+          final core::int #t82 = #t81 as{TypeError,ForNonNullableByDefault} core::int;
+          #t79.{core::Set::add}{Invariant}(#t82){(core::int) → core::bool};
+        }
+    }
+  } =>#t79, block {
+    final core::Map<core::int, core::int> #t83 = <core::int, core::int>{};
+    for (dynamic e in iterable) {
+      final core::Map<core::int, core::int>? #t84 = d;
+      if(!(#t84 == null))
+        for (final core::MapEntry<core::int, core::int> #t85 in #t84{core::Map<core::int, core::int>}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int, core::int>>})
+          #t83.{core::Map::[]=}{Invariant}(#t85.{core::MapEntry::key}{core::int}, #t85.{core::MapEntry::value}{core::int}){(core::int, core::int) → void};
+    }
+  } =>#t83, block {
+    final core::Set<core::int> #t86 = col::LinkedHashSet::•<core::int>();
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+      final core::Iterable<dynamic>? #t87 = a;
+      if(!(#t87 == null))
+        for (final dynamic #t88 in #t87{core::Iterable<dynamic>}) {
+          final core::int #t89 = #t88 as{TypeError,ForNonNullableByDefault} core::int;
+          #t86.{core::Set::add}{Invariant}(#t89){(core::int) → core::bool};
+        }
+    }
+  } =>#t86, block {
+    final core::Set<core::int> #t90 = col::LinkedHashSet::•<core::int>();
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+      final core::Iterable<dynamic>? #t91 = b;
+      if(!(#t91 == null))
+        for (final dynamic #t92 in #t91{core::Iterable<dynamic>}) {
+          final core::int #t93 = #t92 as{TypeError,ForNonNullableByDefault} core::int;
+          #t90.{core::Set::add}{Invariant}(#t93){(core::int) → core::bool};
+        }
+    }
+  } =>#t90, block {
+    final core::Set<core::int> #t94 = col::LinkedHashSet::•<core::int>();
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+      final core::Iterable<dynamic>? #t95 = c;
+      if(!(#t95 == null))
+        for (final dynamic #t96 in #t95{core::Iterable<dynamic>}) {
+          final core::int #t97 = #t96 as{TypeError,ForNonNullableByDefault} core::int;
+          #t94.{core::Set::add}{Invariant}(#t97){(core::int) → core::bool};
+        }
+    }
+  } =>#t94, block {
+    final core::Map<core::int, core::int> #t98 = <core::int, core::int>{};
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+      final core::Map<core::int, core::int>? #t99 = d;
+      if(!(#t99 == null))
+        for (final core::MapEntry<core::int, core::int> #t100 in #t99{core::Map<core::int, core::int>}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int, core::int>>})
+          #t98.{core::Map::[]=}{Invariant}(#t100.{core::MapEntry::key}{core::int}, #t100.{core::MapEntry::value}{core::int}){(core::int, core::int) → void};
+    }
+  } =>#t98];
+}
+static method bar<X extends core::List<core::int>?, Y extends core::Set<core::int>?, Z extends core::Iterable<core::int>?, W extends core::Map<core::int, core::int>?>(core::bool condition, core::Iterable<dynamic> iterable, self::bar::X% x, self::bar::Y% y, self::bar::Z% z, self::bar::W% w) → dynamic {
+  return <core::Object>[ block {
+    final core::Set<core::int> #t101 = col::LinkedHashSet::•<core::int>();
+    for (final dynamic #t102 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:50:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {...x}, // Error.
+        ^") {
+      final core::int #t103 = #t102 as{TypeError,ForNonNullableByDefault} core::int;
+      #t101.{core::Set::add}{Invariant}(#t103){(core::int) → core::bool};
+    }
+  } =>#t101, block {
+    final core::Set<core::int> #t104 = col::LinkedHashSet::•<core::int>();
+    for (final dynamic #t105 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:51:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {...y}, // Error.
+        ^") {
+      final core::int #t106 = #t105 as{TypeError,ForNonNullableByDefault} core::int;
+      #t104.{core::Set::add}{Invariant}(#t106){(core::int) → core::bool};
+    }
+  } =>#t104, block {
+    final core::Set<core::int> #t107 = col::LinkedHashSet::•<core::int>();
+    for (final dynamic #t108 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:52:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {...z}, // Error.
+        ^") {
+      final core::int #t109 = #t108 as{TypeError,ForNonNullableByDefault} core::int;
+      #t107.{core::Set::add}{Invariant}(#t109){(core::int) → core::bool};
+    }
+  } =>#t107, <core::int, core::int>{invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:53:9: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {...w}, // Error.
+        ^": null}, <core::int, core::int>{invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:54:19: Error: Unexpected type 'X' of a map spread entry.  Expected 'dynamic' or a Map.
+    <int, int>{...x}, // Error.
+                  ^": null}, block {
+    final core::Set<core::int> #t110 = col::LinkedHashSet::•<core::int>();
+    #t110.{core::Set::add}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:55:14: Error: Unexpected type 'W' of a spread.  Expected 'dynamic' or an Iterable.
+    <int>{...w}, // Error.
+             ^"){(core::int) → core::bool};
+  } =>#t110, block {
+    final core::Set<core::int> #t111 = col::LinkedHashSet::•<core::int>();
+    if(condition)
+      for (final dynamic #t112 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:56:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {if (condition) ...x}, // Error.
+                       ^") {
+        final core::int #t113 = #t112 as{TypeError,ForNonNullableByDefault} core::int;
+        #t111.{core::Set::add}{Invariant}(#t113){(core::int) → core::bool};
+      }
+  } =>#t111, block {
+    final core::Set<core::int> #t114 = col::LinkedHashSet::•<core::int>();
+    if(condition)
+      for (final dynamic #t115 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:57:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {if (condition) ...y}, // Error.
+                       ^") {
+        final core::int #t116 = #t115 as{TypeError,ForNonNullableByDefault} core::int;
+        #t114.{core::Set::add}{Invariant}(#t116){(core::int) → core::bool};
+      }
+  } =>#t114, block {
+    final core::Set<core::int> #t117 = col::LinkedHashSet::•<core::int>();
+    if(condition)
+      for (final dynamic #t118 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:58:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {if (condition) ...z}, // Error.
+                       ^") {
+        final core::int #t119 = #t118 as{TypeError,ForNonNullableByDefault} core::int;
+        #t117.{core::Set::add}{Invariant}(#t119){(core::int) → core::bool};
+      }
+  } =>#t117, block {
+    final core::Map<core::int, core::int> #t120 = <core::int, core::int>{};
+    if(condition)
+      #t120.{core::Map::[]=}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:59:24: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {if (condition) ...w}, // Error.
+                       ^", null){(core::int, core::int) → void};
+  } =>#t120, block {
+    final core::Set<core::int> #t121 = col::LinkedHashSet::•<core::int>();
+    for (dynamic e in iterable)
+      for (final dynamic #t122 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:60:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (dynamic e in iterable) ...x}, // Error.
+                                    ^") {
+        final core::int #t123 = #t122 as{TypeError,ForNonNullableByDefault} core::int;
+        #t121.{core::Set::add}{Invariant}(#t123){(core::int) → core::bool};
+      }
+  } =>#t121, block {
+    final core::Set<core::int> #t124 = col::LinkedHashSet::•<core::int>();
+    for (dynamic e in iterable)
+      for (final dynamic #t125 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:61:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (dynamic e in iterable) ...y}, // Error.
+                                    ^") {
+        final core::int #t126 = #t125 as{TypeError,ForNonNullableByDefault} core::int;
+        #t124.{core::Set::add}{Invariant}(#t126){(core::int) → core::bool};
+      }
+  } =>#t124, block {
+    final core::Set<core::int> #t127 = col::LinkedHashSet::•<core::int>();
+    for (dynamic e in iterable)
+      for (final dynamic #t128 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:62:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (dynamic e in iterable) ...z}, // Error.
+                                    ^") {
+        final core::int #t129 = #t128 as{TypeError,ForNonNullableByDefault} core::int;
+        #t127.{core::Set::add}{Invariant}(#t129){(core::int) → core::bool};
+      }
+  } =>#t127, block {
+    final core::Map<core::int, core::int> #t130 = <core::int, core::int>{};
+    for (dynamic e in iterable)
+      #t130.{core::Map::[]=}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:63:37: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (dynamic e in iterable) ...w}, // Error.
+                                    ^", null){(core::int, core::int) → void};
+  } =>#t130, block {
+    final core::Set<core::int> #t131 = col::LinkedHashSet::•<core::int>();
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int})
+      for (final dynamic #t132 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:64:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (int i = 0; i < 42; ++i) ...x}, // Error.
+                                     ^") {
+        final core::int #t133 = #t132 as{TypeError,ForNonNullableByDefault} core::int;
+        #t131.{core::Set::add}{Invariant}(#t133){(core::int) → core::bool};
+      }
+  } =>#t131, block {
+    final core::Set<core::int> #t134 = col::LinkedHashSet::•<core::int>();
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int})
+      for (final dynamic #t135 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:65:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (int i = 0; i < 42; ++i) ...y}, // Error.
+                                     ^") {
+        final core::int #t136 = #t135 as{TypeError,ForNonNullableByDefault} core::int;
+        #t134.{core::Set::add}{Invariant}(#t136){(core::int) → core::bool};
+      }
+  } =>#t134, block {
+    final core::Set<core::int> #t137 = col::LinkedHashSet::•<core::int>();
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int})
+      for (final dynamic #t138 in invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:66:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (int i = 0; i < 42; ++i) ...z}, // Error.
+                                     ^") {
+        final core::int #t139 = #t138 as{TypeError,ForNonNullableByDefault} core::int;
+        #t137.{core::Set::add}{Invariant}(#t139){(core::int) → core::bool};
+      }
+  } =>#t137, block {
+    final core::Map<core::int, core::int> #t140 = <core::int, core::int>{};
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int})
+      #t140.{core::Map::[]=}{Invariant}(invalid-expression "pkg/front_end/testcases/nnbd/issue43495.dart:67:38: Error: An expression whose value can be 'null' must be null-checked before it can be dereferenced.
+    {for (int i = 0; i < 42; ++i) ...w}, // Error.
+                                     ^", null){(core::int, core::int) → void};
+  } =>#t140, block {
+    final core::Set<core::int> #t141 = col::LinkedHashSet::•<core::int>();
+    final core::Iterable<dynamic>? #t142 = x;
+    if(!(#t142 == null))
+      for (final dynamic #t143 in #t142{core::Iterable<dynamic>}) {
+        final core::int #t144 = #t143 as{TypeError,ForNonNullableByDefault} core::int;
+        #t141.{core::Set::add}{Invariant}(#t144){(core::int) → core::bool};
+      }
+  } =>#t141, block {
+    final core::Set<core::int> #t145 = col::LinkedHashSet::•<core::int>();
+    final core::Iterable<dynamic>? #t146 = y;
+    if(!(#t146 == null))
+      for (final dynamic #t147 in #t146{core::Iterable<dynamic>}) {
+        final core::int #t148 = #t147 as{TypeError,ForNonNullableByDefault} core::int;
+        #t145.{core::Set::add}{Invariant}(#t148){(core::int) → core::bool};
+      }
+  } =>#t145, block {
+    final core::Set<core::int> #t149 = col::LinkedHashSet::•<core::int>();
+    final core::Iterable<dynamic>? #t150 = z;
+    if(!(#t150 == null))
+      for (final dynamic #t151 in #t150{core::Iterable<dynamic>}) {
+        final core::int #t152 = #t151 as{TypeError,ForNonNullableByDefault} core::int;
+        #t149.{core::Set::add}{Invariant}(#t152){(core::int) → core::bool};
+      }
+  } =>#t149, block {
+    final core::Map<core::int, core::int> #t153 = <core::int, core::int>{};
+    final core::Map<core::int, core::int>? #t154 = w;
+    if(!(#t154 == null))
+      for (final core::MapEntry<core::int, core::int> #t155 in #t154{core::Map<core::int, core::int>}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int, core::int>>})
+        #t153.{core::Map::[]=}{Invariant}(#t155.{core::MapEntry::key}{core::int}, #t155.{core::MapEntry::value}{core::int}){(core::int, core::int) → void};
+  } =>#t153, block {
+    final core::Set<core::int> #t156 = col::LinkedHashSet::•<core::int>();
+    if(condition) {
+      final core::Iterable<dynamic>? #t157 = x;
+      if(!(#t157 == null))
+        for (final dynamic #t158 in #t157{core::Iterable<dynamic>}) {
+          final core::int #t159 = #t158 as{TypeError,ForNonNullableByDefault} core::int;
+          #t156.{core::Set::add}{Invariant}(#t159){(core::int) → core::bool};
+        }
+    }
+  } =>#t156, block {
+    final core::Set<core::int> #t160 = col::LinkedHashSet::•<core::int>();
+    if(condition) {
+      final core::Iterable<dynamic>? #t161 = y;
+      if(!(#t161 == null))
+        for (final dynamic #t162 in #t161{core::Iterable<dynamic>}) {
+          final core::int #t163 = #t162 as{TypeError,ForNonNullableByDefault} core::int;
+          #t160.{core::Set::add}{Invariant}(#t163){(core::int) → core::bool};
+        }
+    }
+  } =>#t160, block {
+    final core::Set<core::int> #t164 = col::LinkedHashSet::•<core::int>();
+    if(condition) {
+      final core::Iterable<dynamic>? #t165 = z;
+      if(!(#t165 == null))
+        for (final dynamic #t166 in #t165{core::Iterable<dynamic>}) {
+          final core::int #t167 = #t166 as{TypeError,ForNonNullableByDefault} core::int;
+          #t164.{core::Set::add}{Invariant}(#t167){(core::int) → core::bool};
+        }
+    }
+  } =>#t164, block {
+    final core::Map<core::int, core::int> #t168 = <core::int, core::int>{};
+    if(condition) {
+      final core::Map<core::int, core::int>? #t169 = w;
+      if(!(#t169 == null))
+        for (final core::MapEntry<core::int, core::int> #t170 in #t169{core::Map<core::int, core::int>}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int, core::int>>})
+          #t168.{core::Map::[]=}{Invariant}(#t170.{core::MapEntry::key}{core::int}, #t170.{core::MapEntry::value}{core::int}){(core::int, core::int) → void};
+    }
+  } =>#t168, block {
+    final core::Set<core::int> #t171 = col::LinkedHashSet::•<core::int>();
+    for (dynamic e in iterable) {
+      final core::Iterable<dynamic>? #t172 = x;
+      if(!(#t172 == null))
+        for (final dynamic #t173 in #t172{core::Iterable<dynamic>}) {
+          final core::int #t174 = #t173 as{TypeError,ForNonNullableByDefault} core::int;
+          #t171.{core::Set::add}{Invariant}(#t174){(core::int) → core::bool};
+        }
+    }
+  } =>#t171, block {
+    final core::Set<core::int> #t175 = col::LinkedHashSet::•<core::int>();
+    for (dynamic e in iterable) {
+      final core::Iterable<dynamic>? #t176 = y;
+      if(!(#t176 == null))
+        for (final dynamic #t177 in #t176{core::Iterable<dynamic>}) {
+          final core::int #t178 = #t177 as{TypeError,ForNonNullableByDefault} core::int;
+          #t175.{core::Set::add}{Invariant}(#t178){(core::int) → core::bool};
+        }
+    }
+  } =>#t175, block {
+    final core::Set<core::int> #t179 = col::LinkedHashSet::•<core::int>();
+    for (dynamic e in iterable) {
+      final core::Iterable<dynamic>? #t180 = z;
+      if(!(#t180 == null))
+        for (final dynamic #t181 in #t180{core::Iterable<dynamic>}) {
+          final core::int #t182 = #t181 as{TypeError,ForNonNullableByDefault} core::int;
+          #t179.{core::Set::add}{Invariant}(#t182){(core::int) → core::bool};
+        }
+    }
+  } =>#t179, block {
+    final core::Map<core::int, core::int> #t183 = <core::int, core::int>{};
+    for (dynamic e in iterable) {
+      final core::Map<core::int, core::int>? #t184 = w;
+      if(!(#t184 == null))
+        for (final core::MapEntry<core::int, core::int> #t185 in #t184{core::Map<core::int, core::int>}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int, core::int>>})
+          #t183.{core::Map::[]=}{Invariant}(#t185.{core::MapEntry::key}{core::int}, #t185.{core::MapEntry::value}{core::int}){(core::int, core::int) → void};
+    }
+  } =>#t183, block {
+    final core::Set<core::int> #t186 = col::LinkedHashSet::•<core::int>();
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+      final core::Iterable<dynamic>? #t187 = x;
+      if(!(#t187 == null))
+        for (final dynamic #t188 in #t187{core::Iterable<dynamic>}) {
+          final core::int #t189 = #t188 as{TypeError,ForNonNullableByDefault} core::int;
+          #t186.{core::Set::add}{Invariant}(#t189){(core::int) → core::bool};
+        }
+    }
+  } =>#t186, block {
+    final core::Set<core::int> #t190 = col::LinkedHashSet::•<core::int>();
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+      final core::Iterable<dynamic>? #t191 = y;
+      if(!(#t191 == null))
+        for (final dynamic #t192 in #t191{core::Iterable<dynamic>}) {
+          final core::int #t193 = #t192 as{TypeError,ForNonNullableByDefault} core::int;
+          #t190.{core::Set::add}{Invariant}(#t193){(core::int) → core::bool};
+        }
+    }
+  } =>#t190, block {
+    final core::Set<core::int> #t194 = col::LinkedHashSet::•<core::int>();
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+      final core::Iterable<dynamic>? #t195 = z;
+      if(!(#t195 == null))
+        for (final dynamic #t196 in #t195{core::Iterable<dynamic>}) {
+          final core::int #t197 = #t196 as{TypeError,ForNonNullableByDefault} core::int;
+          #t194.{core::Set::add}{Invariant}(#t197){(core::int) → core::bool};
+        }
+    }
+  } =>#t194, block {
+    final core::Map<core::int, core::int> #t198 = <core::int, core::int>{};
+    for (core::int i = 0; i.{core::num::<}(42){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+      final core::Map<core::int, core::int>? #t199 = w;
+      if(!(#t199 == null))
+        for (final core::MapEntry<core::int, core::int> #t200 in #t199{core::Map<core::int, core::int>}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int, core::int>>})
+          #t198.{core::Map::[]=}{Invariant}(#t200.{core::MapEntry::key}{core::int}, #t200.{core::MapEntry::value}{core::int}){(core::int, core::int) → void};
+    }
+  } =>#t198];
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue43536.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue43536.dart.weak.modular.expect
new file mode 100644
index 0000000..fc2321b
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue43536.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T%>
+    : super core::Object::•()
+    ;
+  method foo<covariant-by-class E extends self::C::T%>(core::List<self::C::foo::E%> list) → dynamic {
+    core::List<self::C::foo::E%> variable = this.{self::C::method}<self::C::foo::E%>(list){(core::List<self::C::foo::E%>) → core::List<self::C::foo::E%>};
+  }
+  method method<covariant-by-class F extends self::C::T%>(core::List<self::C::method::F%> list) → core::List<self::C::method::F%>
+    return list;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue43591.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue43591.dart.weak.modular.expect
new file mode 100644
index 0000000..7bb6ecb
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue43591.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+extension E<T extends core::Object? = dynamic> on T% {
+  get f = self::E|get#f;
+}
+static method E|get#f<T extends core::Object? = dynamic>(lowered final self::E|get#f::T% #this) → (self::E|get#f::T%) → self::E|get#f::T%
+  return (self::E|get#f::T% t) → self::E|get#f::T% => t;
+static method method1<S extends core::Object? = dynamic>(self::method1::S% s) → dynamic {
+  (self::method1::S%) → self::method1::S% f = self::E|get#f<self::method1::S%>(s);
+}
+static method method2<S extends dynamic>(self::method2::S% s) → dynamic {
+  self::throws(() → void => s{dynamic}.f);
+}
+static method main() → dynamic {}
+static method throws(() → void f) → dynamic {
+  try {
+    f(){() → void};
+  }
+  on core::Object catch(final core::Object e) {
+    return;
+  }
+  throw "Expected exception";
+}
diff --git a/pkg/front_end/testcases/nnbd/issue43689.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue43689.dart.weak.modular.expect
new file mode 100644
index 0000000..aa327e3
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue43689.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue43689.dart:6:17: Error: 'y' is already declared in this scope.
+// late final int? y;
+//                 ^
+// pkg/front_end/testcases/nnbd/issue43689.dart:5:16: Context: Previous declaration of 'y'.
+// late final int y;
+//                ^
+//
+// pkg/front_end/testcases/nnbd/issue43689.dart:10:19: Error: 'x' is already declared in this scope.
+//   late final int? x;
+//                   ^
+// pkg/front_end/testcases/nnbd/issue43689.dart:9:18: Context: Previous declaration of 'x'.
+//   late final int x;
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/issue43689.dart:12:8: Error: 'z' is already declared in this scope.
+//   int? z;
+//        ^
+// pkg/front_end/testcases/nnbd/issue43689.dart:11:7: Context: Previous declaration of 'z'.
+//   int z;
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+late static final [setter] field core::int y;
+static method test() → dynamic {
+  late final core::int x;
+  late final core::int? x = invalid-expression "pkg/front_end/testcases/nnbd/issue43689.dart:10:19: Error: 'x' is already declared in this scope.
+  late final int? x;
+                  ^";
+  core::int z;
+  core::int? z = invalid-expression "pkg/front_end/testcases/nnbd/issue43689.dart:12:8: Error: 'z' is already declared in this scope.
+  int? z;
+       ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue43716a.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue43716a.dart.weak.modular.expect
new file mode 100644
index 0000000..2ed0f16
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue43716a.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue43716a.dart:15:14: Error: A value of type 'Object?' can't be returned from a function with return type 'Object' because 'Object?' is nullable and 'Object' isn't.
+//  - 'Object' is from 'dart:core'.
+//     return z.x; // Error.
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C<X extends self::C<self::C::X%, self::C::X%>? = self::C<dynamic, dynamic>?, Y extends self::C<self::C::Y%, self::C::Y%>? = self::C<dynamic, dynamic>?> extends core::Object {
+  covariant-by-class field self::C::X% x;
+  constructor •(self::C::X% x) → self::C<self::C::X%, self::C::Y%>
+    : self::C::x = x, super core::Object::•()
+    ;
+  method m(covariant-by-class self::C::X% x, covariant-by-class self::C::Y% y) → core::Object {
+    self::C<core::Object?, core::Object?>? z = self::b ?{self::C<core::Object?, core::Object?>?} x : y;
+    if(z == null)
+      throw 0;
+    return invalid-expression "pkg/front_end/testcases/nnbd/issue43716a.dart:15:14: Error: A value of type 'Object?' can't be returned from a function with return type 'Object' because 'Object?' is nullable and 'Object' isn't.
+ - 'Object' is from 'dart:core'.
+    return z.x; // Error.
+             ^" in z{self::C<core::Object?, core::Object?>}.{self::C::x}{core::Object?} as{TypeError,ForNonNullableByDefault} core::Object;
+  }
+}
+static field core::bool b = true;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue43716b.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue43716b.dart.weak.modular.expect
new file mode 100644
index 0000000..98741d8
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue43716b.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue43716b.dart:17:7: Error: The argument type 'int' can't be assigned to the parameter type 'Never'.
+//     z(42); // Error.
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C<X extends (self::C::X%) →? void = (Never) →? void> extends core::Object {
+  covariant-by-class field self::C::X% x;
+  constructor •(self::C::X% x) → self::C<self::C::X%>
+    : self::C::x = x, super core::Object::•()
+    ;
+  method m() → void {
+    (Never) →? void z = self::b ?{(Never) →? void} this.{self::C::x}{self::C::X%} : #C1;
+    if(z == null)
+      return;
+    z{(Never) → void}(invalid-expression "pkg/front_end/testcases/nnbd/issue43716b.dart:17:7: Error: The argument type 'int' can't be assigned to the parameter type 'Never'.
+    z(42); // Error.
+      ^" in 42 as{TypeError,ForNonNullableByDefault} Never){(Never) → void};
+  }
+}
+static field core::bool b = true;
+static method f(core::Object o) → void {}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::f
+}
diff --git a/pkg/front_end/testcases/nnbd/issue43721.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue43721.dart.weak.modular.expect
new file mode 100644
index 0000000..da9759d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue43721.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue43721.dart:13:7: Error: The argument type 'FutureOr<num?>' can't be assigned to the parameter type 'Object' because 'num?' is nullable and 'Object' isn't.
+//  - 'Object' is from 'dart:core'.
+//   foo(z); // Error.
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+static method foo(core::Object x) → dynamic {}
+static method bar(core::bool condition) → dynamic {
+  FutureOr<core::int?>x = null;
+  core::num n = 1;
+  FutureOr<core::num?>z = condition ?{FutureOr<core::num?>} x : n;
+  self::foo(invalid-expression "pkg/front_end/testcases/nnbd/issue43721.dart:13:7: Error: The argument type 'FutureOr<num?>' can't be assigned to the parameter type 'Object' because 'num?' is nullable and 'Object' isn't.
+ - 'Object' is from 'dart:core'.
+  foo(z); // Error.
+      ^" in z as{TypeError,ForNonNullableByDefault} core::Object);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue43918.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue43918.dart.weak.modular.expect
new file mode 100644
index 0000000..9882343
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue43918.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class A<T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  static factory •<T extends core::Object? = dynamic>(self::A::•::T% value) → self::A<self::A::•::T%>
+    return new self::_A::•<self::A::•::T%>(value);
+}
+class _A<T extends core::Object? = dynamic> extends core::Object implements self::A<self::_A::T%> {
+  constructor •(self::_A::T% value) → self::_A<self::_A::T%>
+    : super core::Object::•()
+    ;
+}
+abstract class B<T extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C2]/*isLegacy*/;
+  static factory •<T extends core::Object? = dynamic>(core::int value) → self::B<self::B::•::T%>
+    return new self::_B::•<self::B::•::T%>(value);
+}
+class _B<T extends core::Object? = dynamic> extends core::Object implements self::B<self::_B::T%> {
+  constructor •(core::int value) → self::_B<self::_B::T%>
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::A::•
+  #C2 = constructor-tearoff self::B::•
+}
diff --git a/pkg/front_end/testcases/nnbd/issue44276.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue44276.dart.weak.modular.expect
new file mode 100644
index 0000000..ce89c73
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue44276.dart.weak.modular.expect
@@ -0,0 +1,19 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Base extends core::Object {
+  field core::int? value1 = null;
+  field core::int? value2 = null;
+  synthetic constructor •() → self::Base
+    : super core::Object::•()
+    ;
+}
+static method main() → void {
+  self::fun();
+}
+static method fun() → core::int? {
+  self::Base? a;
+  final core::int? b = let final core::int? #t1 = let final self::Base? #t2 = a in #t2 == null ?{core::int?} null : #t2{self::Base}.{self::Base::value1}{core::int?} in #t1 == null ?{core::int?} let final self::Base? #t3 = a in #t3 == null ?{core::int?} null : #t3{self::Base}.{self::Base::value2}{core::int?} : #t1{core::int};
+  return b;
+}
diff --git a/pkg/front_end/testcases/nnbd/issue44362.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue44362.dart.weak.modular.expect
new file mode 100644
index 0000000..3e32ea9
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue44362.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method foo<X extends core::Object? = dynamic>(self::foo::X? x) → dynamic {
+  if(x is{ForNonNullableByDefault} core::int) {
+    self::bar<dynamic>(x{self::foo::X? & core::int /* '?' & '!' = '!' */});
+  }
+}
+static method bar<Y extends core::Object? = dynamic>(dynamic y) → dynamic {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue44455.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue44455.dart.weak.modular.expect
new file mode 100644
index 0000000..d0065b3
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue44455.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue44455.dart:6:9: Error: Type argument 'X' doesn't conform to the bound 'num' of the type variable 'Y' on 'F'.
+// Try changing type arguments so that they conform to the bounds.
+// class A<X extends F<X>> {}
+//         ^
+// pkg/front_end/testcases/nnbd/issue44455.dart:5:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<Y extends num> = Y Function();
+//           ^
+//
+// pkg/front_end/testcases/nnbd/issue44455.dart:8:10: Error: Type argument 'X' doesn't conform to the bound 'num' of the type variable 'Y' on 'F2'.
+// Try changing type arguments so that they conform to the bounds.
+// class A2<X extends F2<X>> {}
+//          ^
+// pkg/front_end/testcases/nnbd/issue44455.dart:9:12: Context: This is the type variable whose bound isn't conformed to.
+// typedef F2<Y extends num> = Y Function();
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F<Y extends core::num> = () → Y;
+typedef F2<Y extends core::num> = () → Y;
+class A<X extends () → self::A::X = () → dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X>
+    : super core::Object::•()
+    ;
+}
+class A2<X extends () → self::A2::X = () → dynamic> extends core::Object {
+  synthetic constructor •() → self::A2<self::A2::X>
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue44595.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue44595.dart.weak.modular.expect
new file mode 100644
index 0000000..150af53
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue44595.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+typedef Exactly<invariant T extends core::Object? = dynamic> = (T%) → T%;
+extension _extension#0<T extends core::Object? = dynamic> on T% {
+  method checkStaticType = self::_extension#0|checkStaticType;
+  tearoff checkStaticType = self::_extension#0|get#checkStaticType;
+}
+static method id<T extends core::Object? = dynamic>(self::id::T% value) → self::id::T%
+  return value;
+static method main() → dynamic async {
+  FutureOr<core::int>x = 1.{core::num::+}(self::id<core::int>(1)){(core::num) → core::int};
+  FutureOr<core::int>y = let final core::int #t1 = 1.{core::num::+}(self::id<core::int>(1)){(core::num) → core::int} in block {
+    self::_extension#0|checkStaticType<core::int, (core::int) → core::int>(#t1);
+  } =>#t1;
+  FutureOr<core::int>z = let final core::int #t2 = 1.{core::num::+}(self::contextType<core::int>(1)){(core::num) → core::int} in block {
+    self::_extension#0|checkStaticType<core::int, (core::int) → core::int>(#t2);
+  } =>#t2;
+}
+static method _extension#0|checkStaticType<T extends core::Object? = dynamic, R extends (self::_extension#0|checkStaticType::T%) → self::_extension#0|checkStaticType::T% = (dynamic) → dynamic>(lowered final self::_extension#0|checkStaticType::T% #this) → void {}
+static method _extension#0|get#checkStaticType<T extends core::Object? = dynamic>(lowered final self::_extension#0|get#checkStaticType::T% #this) → <R extends (self::_extension#0|get#checkStaticType::T%) → self::_extension#0|get#checkStaticType::T% = (dynamic) → dynamic>() → void
+  return <R extends (self::_extension#0|get#checkStaticType::T%) → self::_extension#0|get#checkStaticType::T% = (dynamic) → dynamic>() → void => self::_extension#0|checkStaticType<self::_extension#0|get#checkStaticType::T%, R>(#this);
+static method contextType<T extends core::Object? = dynamic>(core::Object? o) → self::contextType::T%
+  return o as{ForNonNullableByDefault} self::contextType::T%;
diff --git a/pkg/front_end/testcases/nnbd/issue44857.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue44857.dart.weak.modular.expect
new file mode 100644
index 0000000..528dcbd
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue44857.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef F = (<T extends Never = dynamic>(T) → void) → Never;
+static method main() → void {
+  core::print("Are ${#C1}, ${#C1} identical?");
+  core::print(core::identical(#C1, #C1));
+}
+
+constants  {
+  #C1 = TypeLiteralConstant((<T extends Never* = dynamic>(Never*) →* void) →* Never*)
+}
diff --git a/pkg/front_end/testcases/nnbd/issue45598.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue45598.dart.weak.modular.expect
new file mode 100644
index 0000000..b03a7ab
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue45598.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method foo(<X extends Z% = dynamic, Y extends core::Object? = dynamic, Z extends core::Object? = dynamic>({m: core::Map<Y%, Z%>}) → dynamic bar, core::Map<core::String, core::String> m) → dynamic {
+  bar<core::String, core::String, core::String>(m: m){({m: core::Map<core::String, core::String>}) → dynamic};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/issue45598_2.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue45598_2.dart.weak.modular.expect
new file mode 100644
index 0000000..f0813ae
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue45598_2.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method foo(core::Map<core::String, core::String> m) → dynamic {
+  function bar<X extends Z% = dynamic, Y extends core::Object? = dynamic, Z extends core::Object? = dynamic>({required core::Map<Y%, Z%> m = #C1}) → void {}
+  bar<core::String, core::String, core::String>(m: m){({required m: core::Map<core::String, core::String>}) → void};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/issue47311.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue47311.dart.weak.modular.expect
new file mode 100644
index 0000000..baea864
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue47311.dart.weak.modular.expect
@@ -0,0 +1,68 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+typedef Baz<invariant T extends core::Object? = dynamic> = (T%) → T%;
+class Foo1<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Foo1<self::Foo1::T%>
+    : super core::Object::•()
+    ;
+  method method<covariant-by-class S extends self::Foo1::T%>((self::Foo1::method::S%) → self::Foo1::method::S% x) → void {}
+}
+class Bar1 extends core::Object implements self::Foo1<core::Object> {
+  synthetic constructor •() → self::Bar1
+    : super core::Object::•()
+    ;
+  method method<covariant-by-class T extends core::Object>((self::Bar1::method::T) → self::Bar1::method::T x) → void {}
+}
+class Foo2<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Foo2<self::Foo2::T%>
+    : super core::Object::•()
+    ;
+  method method<V extends self::Foo2::method::S% = self::Foo2::T%, covariant-by-class S extends self::Foo2::T%>((self::Foo2::method::S%) → self::Foo2::method::S% x, (self::Foo2::method::V%) → self::Foo2::method::V% y) → void {}
+}
+class Bar2 extends core::Object implements self::Foo2<core::Object> {
+  synthetic constructor •() → self::Bar2
+    : super core::Object::•()
+    ;
+  method method<V extends self::Bar2::method::T = core::Object, covariant-by-class T extends core::Object>((self::Bar2::method::T) → self::Bar2::method::T x, (self::Bar2::method::V) → self::Bar2::method::V y) → void {}
+}
+class Foo3<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Foo3<self::Foo3::T%>
+    : super core::Object::•()
+    ;
+  method method<V extends self::Foo3::method::S% = FutureOr<self::Foo3::T%>, covariant-by-class S extends FutureOr<self::Foo3::T%>>((self::Foo3::method::S%) → self::Foo3::method::S% x, (self::Foo3::method::V%) → self::Foo3::method::V% y) → void {}
+}
+class Bar3 extends core::Object implements self::Foo3<core::Object> {
+  synthetic constructor •() → self::Bar3
+    : super core::Object::•()
+    ;
+  method method<V extends self::Bar3::method::T = FutureOr<core::Object>, covariant-by-class T extends FutureOr<core::Object>>((self::Bar3::method::T) → self::Bar3::method::T x, (self::Bar3::method::V) → self::Bar3::method::V y) → void {}
+}
+class Foo4<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Foo4<self::Foo4::T%>
+    : super core::Object::•()
+    ;
+  method method<V extends FutureOr<self::Foo4::method::S%> = FutureOr<self::Foo4::T%>, covariant-by-class S extends self::Foo4::T%>((self::Foo4::method::S%) → self::Foo4::method::S% x, (self::Foo4::method::V%) → self::Foo4::method::V% y) → void {}
+}
+class Bar4 extends core::Object implements self::Foo4<core::Object> {
+  synthetic constructor •() → self::Bar4
+    : super core::Object::•()
+    ;
+  method method<V extends FutureOr<self::Bar4::method::T> = FutureOr<core::Object>, covariant-by-class T extends core::Object>((self::Bar4::method::T) → self::Bar4::method::T x, (self::Bar4::method::V) → self::Bar4::method::V y) → void {}
+}
+class Foo5<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Foo5<self::Foo5::T%>
+    : super core::Object::•()
+    ;
+  method method<V extends FutureOr<self::Foo5::method::S%> = FutureOr<FutureOr<self::Foo5::T%>>, covariant-by-class S extends FutureOr<self::Foo5::T%>>((self::Foo5::method::S%) → self::Foo5::method::S% x, (self::Foo5::method::V%) → self::Foo5::method::V% y) → void {}
+}
+class Bar5 extends core::Object implements self::Foo5<core::Object> {
+  synthetic constructor •() → self::Bar5
+    : super core::Object::•()
+    ;
+  method method<V extends FutureOr<self::Bar5::method::T> = FutureOr<FutureOr<core::Object>>, covariant-by-class T extends FutureOr<core::Object>>((self::Bar5::method::T) → self::Bar5::method::T x, (self::Bar5::method::V) → self::Bar5::method::V y) → void {}
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/nnbd/issue_39286.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue_39286.dart.weak.modular.expect
new file mode 100644
index 0000000..ebe9eae
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue_39286.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  method f() → self::D?
+    return new self::D::•();
+  method h() → void {}
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D
+    : super core::Object::•()
+    ;
+  method g() → void {}
+}
+static method test(self::C x) → void {
+  let final self::C #t1 = x in block {
+    #t1.{self::C::f}(){() → self::D?}!.{self::D::g}(){() → void};
+    #t1.{self::C::h}(){() → void};
+  } =>#t1;
+}
+static method main() → dynamic {
+  self::test(new self::C::•());
+}
diff --git a/pkg/front_end/testcases/nnbd/issue_39286_2.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/issue_39286_2.dart.weak.modular.expect
new file mode 100644
index 0000000..261dcc1
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/issue_39286_2.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/issue_39286_2.dart:15:14: Warning: Operand of null-aware operation '!' has type 'String' which excludes null.
+//   x..f()!.g()['Hi!']!..h()!.y = 2;
+//              ^
+//
+// pkg/front_end/testcases/nnbd/issue_39286_2.dart:15:24: Warning: Operand of null-aware operation '!' has type 'C' which excludes null.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/issue_39286_2.dart'.
+//   x..f()!.g()['Hi!']!..h()!.y = 2;
+//                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field core::int y = 42;
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  method f() → self::D?
+    return new self::D::•();
+  method h() → self::C
+    return this;
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D
+    : super core::Object::•()
+    ;
+  method g() → self::D
+    return this;
+  operator [](core::String s) → core::String {
+    return "!${s}!";
+  }
+}
+static method test(self::C x) → void {
+  let final self::C #t1 = x in block {
+    #t1.{self::C::f}(){() → self::D?}!.{self::D::g}(){() → self::D}.{self::D::[]}("Hi!"){(core::String) → core::String}!;
+    #t1.{self::C::h}(){() → self::C}!.{self::C::y} = 2;
+  } =>#t1;
+}
+static method main() → dynamic {
+  self::test(new self::C::•());
+}
diff --git a/pkg/front_end/testcases/nnbd/language_issue1182.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/language_issue1182.dart.weak.modular.expect
new file mode 100644
index 0000000..aa91968
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/language_issue1182.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Foo<S extends core::num> extends core::Object {
+  synthetic constructor •() → self::Foo<self::Foo::S>
+    : super core::Object::•()
+    ;
+  method test1(covariant-by-class self::Foo::S x) → void {
+    (self::Foo::S) → self::Foo::S f = self::Test|get#test<self::Foo::S>(x);
+  }
+}
+extension Test<T extends core::Object? = dynamic> on T% {
+  get test = self::Test|get#test;
+}
+static method Test|get#test<T extends core::Object? = dynamic>(lowered final self::Test|get#test::T% #this) → (self::Test|get#test::T%) → self::Test|get#test::T%
+  return (self::Test|get#test::T% a) → self::Test|get#test::T% => #this;
+static method main() → void {}
diff --git a/pkg/front_end/testcases/nnbd/late.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/late.dart.weak.modular.expect
new file mode 100644
index 0000000..3eaeb2c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/late.dart.weak.modular.expect
@@ -0,0 +1,105 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/late.dart:40:5: Error: Can't assign to the final variable 'lateFinalVariableWithInit'.
+//     lateFinalVariableWithInit = 0;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/late.dart:44:5: Error: Setter not found: 'lateFinalStaticFieldWithInit'.
+//     lateFinalStaticFieldWithInit = 0;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/late.dart:42:5: Error: The setter 'lateFinalInstanceFieldWithInit' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/late.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'lateFinalInstanceFieldWithInit'.
+//     lateFinalInstanceFieldWithInit = 0;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/late.dart:63:3: Error: Setter not found: 'lateFinalTopLevelFieldWithInit'.
+//   lateFinalTopLevelFieldWithInit = 0;
+//   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/late.dart:67:9: Error: Setter not found: 'lateFinalStaticFieldWithInit'.
+//   Class.lateFinalStaticFieldWithInit = 0;
+//         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/late.dart:65:5: Error: The setter 'lateFinalInstanceFieldWithInit' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/late.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'lateFinalInstanceFieldWithInit'.
+//   c.lateFinalInstanceFieldWithInit = 0;
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  late field core::int lateInstanceField;
+  late final [setter] field core::int lateFinalInstanceField1;
+  late final [setter] field core::int lateFinalInstanceField2;
+  late final field core::int lateFinalInstanceFieldWithInit = 0;
+  late field self::Class lateInstanceFieldThis = this;
+  late final field self::Class lateFinalInstanceFieldThis = this;
+  late static field core::int lateStaticField;
+  late static final [setter] field core::int lateFinalStaticField1;
+  late static final [setter] field core::int lateFinalStaticField2;
+  late static final field core::int lateFinalStaticFieldWithInit = 0;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  method method() → dynamic {
+    late core::int lateVariable;
+    late final core::int lateFinalVariable;
+    late final core::int lateFinalVariableWithInit = 0;
+    lateVariable = 0;
+    lateFinalVariable = 0;
+    this.{self::Class::lateInstanceField} = 0;
+    this.{self::Class::lateFinalInstanceField1} = 0;
+    self::Class::lateStaticField = 0;
+    self::Class::lateFinalStaticField1 = 0;
+  }
+  method methodWithErrors() → dynamic {
+    late final core::int lateFinalVariableWithInit = 0;
+    invalid-expression "pkg/front_end/testcases/nnbd/late.dart:40:5: Error: Can't assign to the final variable 'lateFinalVariableWithInit'.
+    lateFinalVariableWithInit = 0;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^";
+    invalid-expression "pkg/front_end/testcases/nnbd/late.dart:42:5: Error: The setter 'lateFinalInstanceFieldWithInit' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/late.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'lateFinalInstanceFieldWithInit'.
+    lateFinalInstanceFieldWithInit = 0;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in this{<unresolved>}.lateFinalInstanceFieldWithInit = 0;
+    invalid-expression "pkg/front_end/testcases/nnbd/late.dart:44:5: Error: Setter not found: 'lateFinalStaticFieldWithInit'.
+    lateFinalStaticFieldWithInit = 0;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+  }
+}
+late static field core::int lateTopLevelField;
+late static final [setter] field core::int lateFinalTopLevelField;
+late static final field core::int lateFinalTopLevelFieldWithInit = 0;
+static method main() → dynamic {}
+static method noErrors() → dynamic {
+  self::lateTopLevelField = 0;
+  self::lateFinalTopLevelField = 0;
+  self::Class c1 = new self::Class::•();
+  c1.{self::Class::method}(){() → dynamic};
+  self::Class c2 = new self::Class::•();
+  c2.{self::Class::lateInstanceField} = 0;
+  c2.{self::Class::lateFinalInstanceField2} = 0;
+  self::Class::lateStaticField = 0;
+  self::Class::lateFinalStaticField2 = 0;
+}
+static method errors() → dynamic {
+  invalid-expression "pkg/front_end/testcases/nnbd/late.dart:63:3: Error: Setter not found: 'lateFinalTopLevelFieldWithInit'.
+  lateFinalTopLevelFieldWithInit = 0;
+  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+  self::Class c = new self::Class::•();
+  invalid-expression "pkg/front_end/testcases/nnbd/late.dart:65:5: Error: The setter 'lateFinalInstanceFieldWithInit' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/late.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'lateFinalInstanceFieldWithInit'.
+  c.lateFinalInstanceFieldWithInit = 0;
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in c{<unresolved>}.lateFinalInstanceFieldWithInit = 0;
+  c.{self::Class::methodWithErrors}(){() → dynamic};
+  invalid-expression "pkg/front_end/testcases/nnbd/late.dart:67:9: Error: Setter not found: 'lateFinalStaticFieldWithInit'.
+  Class.lateFinalStaticFieldWithInit = 0;
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+}
diff --git a/pkg/front_end/testcases/nnbd/later.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/later.dart.weak.modular.expect
new file mode 100644
index 0000000..63fc71a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/later.dart.weak.modular.expect
@@ -0,0 +1,138 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/later.dart:12:7: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   foo(late int x) {}
+//       ^^^^
+//
+// pkg/front_end/testcases/nnbd/later.dart:15:5: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+// bar(late int x) {}
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/later.dart:20:28: Error: 'catch' must be followed by '(identifier)' or '(identifier, identifier)'.
+// No types are needed, the first is given by 'on', the second is always 'StackTrace'.
+//   } on dynamic catch (late e, late t) {}
+//                            ^
+//
+// pkg/front_end/testcases/nnbd/later.dart:20:31: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   } on dynamic catch (late e, late t) {}
+//                               ^^^^
+//
+// pkg/front_end/testcases/nnbd/later.dart:20:36: Error: 'catch' must be followed by '(identifier)' or '(identifier, identifier)'.
+// No types are needed, the first is given by 'on', the second is always 'StackTrace'.
+//   } on dynamic catch (late e, late t) {}
+//                                    ^
+//
+// pkg/front_end/testcases/nnbd/later.dart:21:8: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   for (late int i = 0; i < 10; ++i) {
+//        ^^^^
+//
+// pkg/front_end/testcases/nnbd/later.dart:24:8: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   for (late String s in ["baz"]) {
+//        ^^^^
+//
+// pkg/front_end/testcases/nnbd/later.dart:27:9: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   [for (late int i = 0; i < 10; ++i) i];
+//         ^^^^
+//
+// pkg/front_end/testcases/nnbd/later.dart:31:14: Error: Can't have modifier 'late' here.
+// Try removing 'late'.
+//   await for (late String s in new Stream.fromIterable(["hest"])) {
+//              ^^^^
+//
+// pkg/front_end/testcases/nnbd/later.dart:38:20: Error: `await` expressions are not supported in late local initializers.
+//   late String s1 = await hest();
+//                    ^^^^^
+//
+// pkg/front_end/testcases/nnbd/later.dart:39:30: Error: `await` expressions are not supported in late local initializers.
+//   late String s2 = '${fisk}${await hest()}${fisk}';
+//                              ^^^^^
+//
+// pkg/front_end/testcases/nnbd/later.dart:44:18: Error: Can't have a late final field in a class with a const constructor.
+//   late final int x = 42;
+//                  ^
+// pkg/front_end/testcases/nnbd/later.dart:46:9: Context: This constructor is const.
+//   const B();
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+class A extends core::Object {
+  field core::int a = 42;
+  late field core::int b = this.{self::A::a}{core::int}.{core::num::*}(2){(core::num) → core::int}.{core::int::>>}(1){(core::int) → core::int};
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method foo(core::int x) → dynamic {}
+}
+class B extends core::Object /*hasConstConstructor*/  {
+  late final field core::int x = 42;
+  const constructor •() → self::B
+    : super core::Object::•()
+    ;
+}
+class C extends core::Object {
+  late final [setter] field core::int x;
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  method initVars() → dynamic {
+    this.{self::C::x} = 42;
+  }
+}
+static method bar(core::int x) → dynamic {}
+static method baz() → dynamic {
+  {
+    {
+      invalid-expression "pkg/front_end/testcases/nnbd/later.dart:20:36: Error: 'catch' must be followed by '(identifier)' or '(identifier, identifier)'.
+No types are needed, the first is given by 'on', the second is always 'StackTrace'.
+  } on dynamic catch (late e, late t) {}
+                                   ^";
+    }
+    try {
+      throw "baz";
+    }
+    on dynamic catch(final dynamic late, final core::StackTrace e) {
+    }
+  }
+  for (core::int i = 0; i.{core::num::<}(10){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+    core::print("baz");
+  }
+  for (core::String s in <core::String>["baz"]) {
+    core::print(s);
+  }
+  block {
+    final core::List<core::int> #t1 = <core::int>[];
+    for (core::int i = 0; i.{core::num::<}(10){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int})
+      #t1.{core::List::add}{Invariant}(i){(core::int) → void};
+  } =>#t1;
+}
+static method hest() → dynamic async {
+  await for (core::String s in asy::Stream::fromIterable<core::String>(<core::String>["hest"])) {
+    core::print(s);
+  }
+  return "hest";
+}
+static method fisk() → dynamic async {
+  late core::String s1 = invalid-expression "pkg/front_end/testcases/nnbd/later.dart:38:20: Error: `await` expressions are not supported in late local initializers.
+  late String s1 = await hest();
+                   ^^^^^";
+  late core::String s2 = "${#C1}${invalid-expression "pkg/front_end/testcases/nnbd/later.dart:39:30: Error: `await` expressions are not supported in late local initializers.
+  late String s2 = '\${fisk}\${await hest()}\${fisk}';
+                             ^^^^^"}${#C1}";
+  late core::Function f = () → asy::Future<dynamic> async => await self::hest();
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::fisk
+}
diff --git a/pkg/front_end/testcases/nnbd/lhs_of_if_null.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/lhs_of_if_null.dart.weak.modular.expect
new file mode 100644
index 0000000..42bf683
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/lhs_of_if_null.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method f() → core::Object
+  return let final core::Object? #t1 = self::g<core::Object?>(null) in #t1 == null ?{core::Object} 0 : #t1{core::Object};
+static method g<T extends core::Object? = dynamic>(self::g::T% t) → self::g::T%
+  return t;
+static method main() → dynamic {
+  core::print(self::f());
+}
diff --git a/pkg/front_end/testcases/nnbd/list_constructor.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/list_constructor.dart.weak.modular.expect
new file mode 100644
index 0000000..6ebdc4c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/list_constructor.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/list_constructor.dart:9:7: Error: Can't use the default List constructor.
+// Try using List.filled instead.
+//   new List<T>(42);
+//       ^
+//
+// pkg/front_end/testcases/nnbd/list_constructor.dart:10:7: Error: Can't use the default List constructor.
+// Try using List.filled instead.
+//   new List<int?>(42);
+//       ^
+//
+// pkg/front_end/testcases/nnbd/list_constructor.dart:11:7: Error: Can't use the default List constructor.
+// Try using List.filled instead.
+//   new List<int>(42);
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method foo<T extends core::Object?>() → dynamic {
+  invalid-expression "pkg/front_end/testcases/nnbd/list_constructor.dart:9:7: Error: Can't use the default List constructor.
+Try using List.filled instead.
+  new List<T>(42);
+      ^" in core::List::•<self::foo::T%>(42);
+  invalid-expression "pkg/front_end/testcases/nnbd/list_constructor.dart:10:7: Error: Can't use the default List constructor.
+Try using List.filled instead.
+  new List<int?>(42);
+      ^" in core::List::•<core::int?>(42);
+  invalid-expression "pkg/front_end/testcases/nnbd/list_constructor.dart:11:7: Error: Can't use the default List constructor.
+Try using List.filled instead.
+  new List<int>(42);
+      ^" in core::List::•<core::int>(42);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/load_library.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/load_library.dart.weak.modular.expect
new file mode 100644
index 0000000..885e631
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/load_library.dart.weak.modular.expect
@@ -0,0 +1,19 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "dart:math" deferred as math;
+
+static method main() → dynamic {
+  asy::Future<dynamic> v1 = LoadLibrary(math);
+  v1.{asy::Future::then}<Null>((dynamic _) → Null {}){((dynamic) → FutureOr<Null>, {onError: core::Function?}) → asy::Future<Null>};
+  () → asy::Future<dynamic> v2 = #C1;
+  v2(){() → asy::Future<dynamic>}.{asy::Future::then}<Null>((dynamic _) → Null {}){((dynamic) → FutureOr<Null>, {onError: core::Function?}) → asy::Future<Null>};
+}
+static method _#loadLibrary_math() → asy::Future<dynamic>
+  return LoadLibrary(math);
+
+constants  {
+  #C1 = static-tearoff self::_#loadLibrary_math
+}
diff --git a/pkg/front_end/testcases/nnbd/main_declaration.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/main_declaration.dart.weak.modular.expect
new file mode 100644
index 0000000..9319364
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/main_declaration.dart.weak.modular.expect
@@ -0,0 +1,189 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+
+import "org-dartlang-testcase:///main_declaration_class_lib.dart" as class_lib;
+import "org-dartlang-testcase:///main_declaration_extension_lib.dart" as extension_lib;
+import "org-dartlang-testcase:///main_declaration_field_lib.dart" as field_lib;
+import "org-dartlang-testcase:///main_declaration_getter_lib.dart" as getter_lib;
+import "org-dartlang-testcase:///main_declaration_method_extra_optional_parameters_lib.dart" as method_extra_optional_parameters_lib;
+import "org-dartlang-testcase:///main_declaration_method_named_parameters_lib.dart" as method_named_parameters_lib;
+import "org-dartlang-testcase:///main_declaration_method_one_optional_parameter_lib.dart" as method_one_optional_parameter_lib;
+import "org-dartlang-testcase:///main_declaration_method_one_parameter_lib.dart" as method_one_parameter_lib;
+import "org-dartlang-testcase:///main_declaration_method_one_required_optional_lib.dart" as method_one_required_optional_lib;
+import "org-dartlang-testcase:///main_declaration_method_required_named_parameters_lib.dart" as method_required_named_parameters_lib;
+import "org-dartlang-testcase:///main_declaration_method_too_many_parameters_lib.dart" as method_too_many_parameters_lib;
+import "org-dartlang-testcase:///main_declaration_method_two_optional_parameters_lib.dart" as method_two_optional_parameters_lib;
+import "org-dartlang-testcase:///main_declaration_method_two_parameters_lib.dart" as method_two_parameters_lib;
+import "org-dartlang-testcase:///main_declaration_method_wrong_parameter_type_lib.dart" as method_wrong_parameter_type_lib;
+import "org-dartlang-testcase:///main_declaration_setter_lib.dart" as setter_lib;
+import "org-dartlang-testcase:///main_declaration_typedef_lib.dart" as typedef_lib;
+
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_class_lib.dart:5:7: Error: The 'main' declaration must be a function declaration.
+// class main /* error */ {}
+//       ^
+//
+import self as self2;
+import "dart:core" as core;
+
+class main extends core::Object {
+  synthetic constructor •() → self2::main
+    : super core::Object::•()
+    ;
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_extension_lib.dart:5:11: Error: The 'main' declaration must be a function declaration.
+// extension main /* error */ on Object {}
+//           ^
+//
+import self as self3;
+import "dart:core" as core;
+
+extension main on core::Object {
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_field_lib.dart:5:17: Error: The 'main' declaration must be a function declaration.
+// void Function() main /* error */ = () {};
+//                 ^^^^
+//
+import self as self4;
+
+static field () → void main = () → void {};
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_getter_lib.dart:5:21: Error: The 'main' declaration must be a function declaration.
+// void Function() get main /* error */ => () {};
+//                     ^^^^
+//
+import self as self5;
+
+static get main() → () → void
+  return () → void {};
+
+library /*isNonNullableByDefault*/;
+import self as self6;
+import "dart:core" as core;
+
+static method main(core::List<core::String> args, dynamic other, [dynamic extra = #C1]) → void {}
+
+library /*isNonNullableByDefault*/;
+import self as self7;
+import "dart:core" as core;
+
+static method main({core::List<core::String> args = #C2}) → void {}
+
+library /*isNonNullableByDefault*/;
+import self as self8;
+import "dart:core" as core;
+
+static method main([core::List<core::String>? args = #C1]) → void {}
+
+library /*isNonNullableByDefault*/;
+import self as self9;
+import "dart:core" as core;
+
+static method main(core::List<core::String> args) → void {}
+
+library /*isNonNullableByDefault*/;
+import self as self10;
+import "dart:core" as core;
+
+static method main(core::List<core::String> args, [dynamic other = #C1]) → void {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_method_required_named_parameters_lib.dart:5:6: Error: The 'main' method cannot have required named parameters.
+// void main({required List<String> args}) /* error */ {}
+//      ^^^^
+//
+import self as self11;
+import "dart:core" as core;
+
+static method main({required core::List<core::String> args = #C1}) → void {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_method_too_many_parameters_lib.dart:5:6: Error: The 'main' method must have at most 2 required parameters.
+// void main(List<String> args, a, b) /* error */ {}
+//      ^^^^
+//
+import self as self12;
+import "dart:core" as core;
+
+static method main(core::List<core::String> args, dynamic a, dynamic b) → void {}
+
+library /*isNonNullableByDefault*/;
+import self as self13;
+import "dart:core" as core;
+
+static method main([core::List<core::String> args = #C2, dynamic other = #C1]) → void {}
+
+library /*isNonNullableByDefault*/;
+import self as self14;
+import "dart:core" as core;
+
+static method main(core::List<core::String> args, dynamic other) → void {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_method_wrong_parameter_type_lib.dart:5:6: Error: The type 'Set<String>' of the first parameter of the 'main' method is not a supertype of 'List<String>'.
+//  - 'Set' is from 'dart:core'.
+//  - 'List' is from 'dart:core'.
+// void main(Set<String> args) /* error */ {}
+//      ^^^^
+//
+import self as self15;
+import "dart:core" as core;
+
+static method main(core::Set<core::String> args) → void {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_setter_lib.dart:5:10: Error: The 'main' declaration must be a function declaration.
+// void set main(void Function() f) /* error */ {}
+//          ^^^^
+//
+import self as self16;
+
+static set main(() → void f) → void {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/main_declaration_typedef_lib.dart:5:9: Error: The 'main' declaration must be a function declaration.
+// typedef main /* error */ = void Function();
+//         ^
+//
+import self as self17;
+
+typedef main = () → void;
+
+constants  {
+  #C1 = null
+  #C2 = <core::String*>[]
+}
diff --git a/pkg/front_end/testcases/nnbd/missing_required_named_parameter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/missing_required_named_parameter.dart.weak.modular.expect
new file mode 100644
index 0000000..a736a23
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/missing_required_named_parameter.dart.weak.modular.expect
@@ -0,0 +1,65 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/missing_required_named_parameter.dart:15:6: Error: Required named parameter 's' must be provided.
+//   foo();
+//      ^
+// pkg/front_end/testcases/nnbd/missing_required_named_parameter.dart:5:6: Context: Found this candidate, but the arguments don't match.
+// void foo({required String s}) {}
+//      ^^^
+//
+// pkg/front_end/testcases/nnbd/missing_required_named_parameter.dart:16:8: Error: Required named parameter 'x' must be provided.
+//   new A();
+//        ^
+// pkg/front_end/testcases/nnbd/missing_required_named_parameter.dart:9:3: Context: Found this candidate, but the arguments don't match.
+//   A({required int x});
+//   ^
+//
+// pkg/front_end/testcases/nnbd/missing_required_named_parameter.dart:18:8: Error: Required named parameter 'y' must be provided.
+//   a.foo();
+//        ^
+//
+// pkg/front_end/testcases/nnbd/missing_required_named_parameter.dart:19:6: Error: Required named parameter 's' must be provided.
+//   a.f();
+//      ^
+//
+// pkg/front_end/testcases/nnbd/missing_required_named_parameter.dart:20:4: Error: Required named parameter 's' must be provided.
+//   g();
+//    ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field ({required s: core::String}) → void f = ({required core::String s = #C1}) → void {};
+  constructor •({required core::int x = #C1}) → self::A
+    : super core::Object::•()
+    ;
+  method foo({required core::int y = #C1}) → dynamic {}
+}
+static field ({required s: core::String}) → void g = ({required core::String s = #C1}) → void {};
+static method foo({required core::String s = #C1}) → void {}
+static method bar() → dynamic {
+  invalid-expression "pkg/front_end/testcases/nnbd/missing_required_named_parameter.dart:15:6: Error: Required named parameter 's' must be provided.
+  foo();
+     ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/missing_required_named_parameter.dart:16:8: Error: Required named parameter 'x' must be provided.
+  new A();
+       ^";
+  self::A a = new self::A::•(x: 42);
+  invalid-expression "pkg/front_end/testcases/nnbd/missing_required_named_parameter.dart:18:8: Error: Required named parameter 'y' must be provided.
+  a.foo();
+       ^" in a.{self::A::foo}{<inapplicable>}.(){() → invalid-type};
+  invalid-expression "pkg/front_end/testcases/nnbd/missing_required_named_parameter.dart:19:6: Error: Required named parameter 's' must be provided.
+  a.f();
+     ^" in a.{self::A::f}{({required s: core::String}) → void}{<inapplicable>}.();
+  invalid-expression "pkg/front_end/testcases/nnbd/missing_required_named_parameter.dart:20:4: Error: Required named parameter 's' must be provided.
+  g();
+   ^" in self::g{<inapplicable>}.();
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/mix_in_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/mix_in_field.dart.weak.modular.expect
new file mode 100644
index 0000000..8015a15
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/mix_in_field.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+class Mixin extends core::Object {
+  field FutureOr<Null>m = null;
+  synthetic constructor •() → self::Mixin
+    : super core::Object::•()
+    ;
+}
+abstract class _Class&Object&Mixin = core::Object with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Object&Mixin
+    : super core::Object::•()
+    ;
+  mixin-super-stub get m() → FutureOr<Null>
+    return super.{self::Mixin::m};
+  mixin-super-stub set m(FutureOr<Null>value) → void
+    return super.{self::Mixin::m} = value;
+}
+class Class extends self::_Class&Object&Mixin {
+  synthetic constructor •() → self::Class
+    : super self::_Class&Object&Mixin::•()
+    ;
+  method test(dynamic t1) → dynamic {
+    this.{self::_Class&Object&Mixin::m} = t1 as{TypeError,ForDynamic,ForNonNullableByDefault} FutureOr<Null>;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/mutual_subtype_norm.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/mutual_subtype_norm.dart.weak.modular.expect
new file mode 100644
index 0000000..b9ee95d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/mutual_subtype_norm.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/mutual_subtype_norm.dart:21:16: Error: Can't return a value from a void function.
+//     return new Future<Null>.value(null); // error
+//                ^
+//
+// pkg/front_end/testcases/nnbd/mutual_subtype_norm.dart:25:16: Error: Can't return a value from a void function.
+//     return new Future<Null>.value(null); // error
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+import "dart:async";
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method method1() → void {}
+  method method2() → FutureOr<void> {}
+  method method3() → FutureOr<void> {}
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+  method method1() → void {}
+  method method2() → void {}
+  method method3() → FutureOr<void> {}
+}
+class C extends core::Object implements self::A, self::B {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  method method1() → void {
+    return invalid-expression "pkg/front_end/testcases/nnbd/mutual_subtype_norm.dart:21:16: Error: Can't return a value from a void function.
+    return new Future<Null>.value(null); // error
+               ^" in asy::Future::value<Null>(null);
+  }
+  method method2() → void {
+    return invalid-expression "pkg/front_end/testcases/nnbd/mutual_subtype_norm.dart:25:16: Error: Can't return a value from a void function.
+    return new Future<Null>.value(null); // error
+               ^" in asy::Future::value<Null>(null);
+  }
+  method method3() → FutureOr<void> {
+    return asy::Future::value<Null>(null);
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/never_bound.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/never_bound.dart.weak.modular.expect
new file mode 100644
index 0000000..08602d8
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/never_bound.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/never_bound.dart:10:3: Error: Type argument 'Null' doesn't conform to the bound 'Never' of the type variable 'T' on 'GenericNever'.
+// Try changing type arguments so that they conform to the bounds.
+//   GenericNever<Null>();
+//   ^
+// pkg/front_end/testcases/nnbd/never_bound.dart:5:20: Context: This is the type variable whose bound isn't conformed to.
+// class GenericNever<T extends Never> {
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/never_bound.dart:11:3: Error: Type argument 'void' doesn't conform to the bound 'Never' of the type variable 'T' on 'GenericNever'.
+// Try changing type arguments so that they conform to the bounds.
+//   GenericNever<void>();
+//   ^
+// pkg/front_end/testcases/nnbd/never_bound.dart:5:20: Context: This is the type variable whose bound isn't conformed to.
+// class GenericNever<T extends Never> {
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/never_bound.dart:12:3: Error: Type argument 'int' doesn't conform to the bound 'Never' of the type variable 'T' on 'GenericNever'.
+// Try changing type arguments so that they conform to the bounds.
+//   GenericNever<int>();
+//   ^
+// pkg/front_end/testcases/nnbd/never_bound.dart:5:20: Context: This is the type variable whose bound isn't conformed to.
+// class GenericNever<T extends Never> {
+//                    ^
+//
+import self as self;
+import "dart:core" as core;
+
+class GenericNever<T extends Never> extends core::Object {
+  synthetic constructor •() → self::GenericNever<self::GenericNever::T>
+    : super core::Object::•()
+    ;
+  method getParamType() → dynamic
+    return self::GenericNever::T;
+}
+static method errors() → dynamic {
+  new self::GenericNever::•<Null>();
+  new self::GenericNever::•<void>();
+  new self::GenericNever::•<core::int>();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/never_calls.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/never_calls.dart.weak.modular.expect
new file mode 100644
index 0000000..a1ee958
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/never_calls.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:_internal" as _in;
+import "dart:core" as core;
+
+static method propertyGet(Never never) → dynamic {
+  Never v1 = let final Never #t1 = (let final Never #t2 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.foo in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  Never v2 = let final Never #t3 = (let final Never #t4 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.hashCode in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  Never v3 = let final Never #t5 = (let final Never #t6 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.runtimeType in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  Never v4 = let final Never #t7 = (let final Never #t8 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.toString in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  Never v5 = let final Never #t9 = (let final Never #t10 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.noSuchMethod in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+}
+static method propertySet(Never never) → dynamic {
+  core::int v1 = (let final Never #t11 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.foo = 42;
+}
+static method methodInvocation(Never never, core::Invocation invocation) → dynamic {
+  Never v1 = let final Never #t12 = (let final Never #t13 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.foo() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  Never v2 = let final Never #t14 = (let final Never #t15 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.hashCode() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  Never v3 = let final Never #t16 = (let final Never #t17 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.runtimeType() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  Never v4 = let final Never #t18 = (let final Never #t19 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.toString() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  Never v5 = let final Never #t20 = (let final Never #t21 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.toString(foo: 42) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  Never v6 = let final Never #t22 = (let final Never #t23 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.noSuchMethod(invocation) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  Never v7 = let final Never #t24 = (let final Never #t25 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.noSuchMethod(42) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+}
+static method equals(Never never) → dynamic {
+  core::bool v1 = (let final Never #t26 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) == null;
+  Never v2 = let final Never #t27 = (let final Never #t28 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) =={core::Object::==}{(dynamic) → Never} (let final Never #t29 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+}
+static method operator(Never never) → dynamic {
+  Never v1 = let final Never #t30 = (let final Never #t31 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.+(let final Never #t32 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  Never v2 = let final Never #t33 = (let final Never #t34 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.unary-() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  Never v3 = let final Never #t35 = (let final Never #t36 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.[](let final Never #t37 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  Never v4 = let final Never #t38 = let final Never #t39 = let final Never #t40 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.") in let final Never #t41 = let final Never #t42 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.") in let final Never #t43 = let final Never #t44 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.") in let final void #t45 = #t39{Never}.[]=(#t41, #t43) in #t43 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/never_equals.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/never_equals.dart.weak.modular.expect
new file mode 100644
index 0000000..3863424
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/never_equals.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:_internal" as _in;
+import "dart:core" as core;
+
+static method test(Never nonNullableNever, Never? nullableNever) → dynamic {
+  Never v1 = let final Never #t1 = (let final Never #t2 = nonNullableNever in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) =={core::Object::==}{(dynamic) → Never} (let final Never #t3 = nonNullableNever in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  core::bool v2 = nullableNever =={core::Object::==}{(core::Object) → core::bool} nullableNever;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/never_receiver.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/never_receiver.dart.weak.modular.expect
new file mode 100644
index 0000000..910a2cd
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/never_receiver.dart.weak.modular.expect
@@ -0,0 +1,124 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/never_receiver.dart:24:3: Warning: Operand of null-aware operation '?.' has type 'Never' which excludes null.
+//   x?.foo(); // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/never_receiver.dart:25:3: Warning: Operand of null-aware operation '?.' has type 'Never' which excludes null.
+//   x?.bar; // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/never_receiver.dart:26:3: Warning: Operand of null-aware operation '?.' has type 'Never' which excludes null.
+//   x?.baz = 42; // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/never_receiver.dart:27:3: Warning: Operand of null-aware operation '?.' has type 'Never' which excludes null.
+//   x?[42]; // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/never_receiver.dart:28:3: Warning: Operand of null-aware operation '?.' has type 'Never' which excludes null.
+//   x?[42] = 42; // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/never_receiver.dart:30:5: Error: The method 'foo' isn't defined for the class 'Never?'.
+// Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+//   y.foo(); // Error.
+//     ^^^
+//
+// pkg/front_end/testcases/nnbd/never_receiver.dart:31:5: Error: The getter 'bar' isn't defined for the class 'Never?'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'bar'.
+//   y.bar; // Error.
+//     ^^^
+//
+// pkg/front_end/testcases/nnbd/never_receiver.dart:32:5: Error: The setter 'baz' isn't defined for the class 'Never?'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'baz'.
+//   y.baz = 42; // Error.
+//     ^^^
+//
+// pkg/front_end/testcases/nnbd/never_receiver.dart:33:4: Error: The method 'call' isn't defined for the class 'Never?'.
+// Try correcting the name to the name of an existing method, or defining a method named 'call'.
+//   y(); // Error.
+//    ^
+//
+// pkg/front_end/testcases/nnbd/never_receiver.dart:34:4: Error: The operator '+' isn't defined for the class 'Never?'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//   y++; // Error.
+//    ^
+//
+// pkg/front_end/testcases/nnbd/never_receiver.dart:35:5: Error: The operator '+' isn't defined for the class 'Never?'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//   y += 1; // Error.
+//     ^
+//
+// pkg/front_end/testcases/nnbd/never_receiver.dart:36:4: Error: The operator '[]' isn't defined for the class 'Never?'.
+// Try correcting the operator to an existing operator, or defining a '[]' operator.
+//   y[42]; // Error.
+//    ^
+//
+// pkg/front_end/testcases/nnbd/never_receiver.dart:37:4: Error: The operator '[]=' isn't defined for the class 'Never?'.
+// Try correcting the operator to an existing operator, or defining a '[]=' operator.
+//   y[42] = 42; // Error.
+//    ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+static method foo(Never x, Never? y) → dynamic {
+  core::String local0 = y.{core::Object::toString}(){() → core::String};
+  core::int local1 = y.{core::Object::hashCode}{core::int};
+  let final Never #t1 = (let final Never #t2 = x in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.foo() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never #t3 = (let final Never #t4 = x in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.bar in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  (let final Never #t5 = x in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.baz = 42;
+  let final Never #t6 = (let final Never #t7 = x in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.call() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never #t8 = (let final Never #t9 = x in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.[](42) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  (let final Never #t10 = x in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.[]=(42, 42);
+  let final Never #t11 = x = let final Never #t12 = (let final Never #t13 = x in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.+(1) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.") in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never #t14 = x = let final Never #t15 = (let final Never #t16 = x in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.+(1) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.") in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never? #t17 = y in #t17 == null ?{Null} null : let final Never #t18 = (let final Never #t19 = #t17{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.foo() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never? #t20 = y in #t20 == null ?{Null} null : let final Never #t21 = (let final Never #t22 = #t20{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.bar in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never? #t23 = y in #t23 == null ?{core::int?} null : (let final Never #t24 = #t23{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.baz = 42;
+  let final Never? #t25 = y in #t25 == null ?{Null} null : let final Never #t26 = (let final Never #t27 = #t25{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.call() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never? #t28 = y in #t28 == null ?{Null} null : let final Never #t29 = (let final Never #t30 = #t28{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.[](42) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never? #t31 = y in #t31 == null ?{core::int?} null : (let final Never #t32 = #t31{Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.[]=(42, 42);
+  let final Never #t33 = let final Never #t34 = x in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.") in #t33 == null ?{Null} null : let final Never #t35 = (let final Never #t36 = #t33 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.foo() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never #t37 = let final Never #t38 = x in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.") in #t37 == null ?{Null} null : let final Never #t39 = (let final Never #t40 = #t37 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.bar in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never #t41 = let final Never #t42 = x in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.") in #t41 == null ?{core::int?} null : (let final Never #t43 = #t41 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.baz = 42;
+  let final Never #t44 = let final Never #t45 = x in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.") in #t44 == null ?{Null} null : let final Never #t46 = (let final Never #t47 = #t44 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.[](42) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never #t48 = let final Never #t49 = x in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.") in #t48 == null ?{core::int?} null : (let final Never #t50 = #t48 in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.[]=(42, 42);
+  invalid-expression "pkg/front_end/testcases/nnbd/never_receiver.dart:30:5: Error: The method 'foo' isn't defined for the class 'Never?'.
+Try correcting the name to the name of an existing method, or defining a method named 'foo'.
+  y.foo(); // Error.
+    ^^^" in y{<unresolved>}.foo();
+  invalid-expression "pkg/front_end/testcases/nnbd/never_receiver.dart:31:5: Error: The getter 'bar' isn't defined for the class 'Never?'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'bar'.
+  y.bar; // Error.
+    ^^^" in y{<unresolved>}.bar;
+  invalid-expression "pkg/front_end/testcases/nnbd/never_receiver.dart:32:5: Error: The setter 'baz' isn't defined for the class 'Never?'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'baz'.
+  y.baz = 42; // Error.
+    ^^^" in y{<unresolved>}.baz = 42;
+  invalid-expression "pkg/front_end/testcases/nnbd/never_receiver.dart:33:4: Error: The method 'call' isn't defined for the class 'Never?'.
+Try correcting the name to the name of an existing method, or defining a method named 'call'.
+  y(); // Error.
+   ^" in y{<unresolved>}.call();
+  y = invalid-expression "pkg/front_end/testcases/nnbd/never_receiver.dart:34:4: Error: The operator '+' isn't defined for the class 'Never?'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+  y++; // Error.
+   ^" in y{<unresolved>}.+(1) as{TypeError,ForDynamic,ForNonNullableByDefault} Never?;
+  y = invalid-expression "pkg/front_end/testcases/nnbd/never_receiver.dart:35:5: Error: The operator '+' isn't defined for the class 'Never?'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+  y += 1; // Error.
+    ^" in y{<unresolved>}.+(1) as{TypeError,ForDynamic,ForNonNullableByDefault} Never?;
+  invalid-expression "pkg/front_end/testcases/nnbd/never_receiver.dart:36:4: Error: The operator '[]' isn't defined for the class 'Never?'.
+Try correcting the operator to an existing operator, or defining a '[]' operator.
+  y[42]; // Error.
+   ^" in y{<unresolved>}.[](42);
+  invalid-expression "pkg/front_end/testcases/nnbd/never_receiver.dart:37:4: Error: The operator '[]=' isn't defined for the class 'Never?'.
+Try correcting the operator to an existing operator, or defining a '[]=' operator.
+  y[42] = 42; // Error.
+   ^" in y{<unresolved>}.[]=(42, 42);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart.weak.modular.expect
new file mode 100644
index 0000000..ce4e2f2
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart.weak.modular.expect
@@ -0,0 +1,131 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:7:6: Error: Expected an identifier, but got '['.
+// Try inserting an identifier before '['.
+//   c?.[42];
+//      ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:8:6: Error: Expected an identifier, but got '['.
+// Try inserting an identifier before '['.
+//   c?.[42] = 42;
+//      ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:8:11: Error: Can't assign to this.
+//   c?.[42] = 42;
+//           ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:9:6: Error: Expected an identifier, but got '['.
+// Try inserting an identifier before '['.
+//   c?.[42]++;
+//      ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:9:6: Error: Can't assign to this.
+//   c?.[42]++;
+//      ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:10:8: Error: Expected an identifier, but got '['.
+// Try inserting an identifier before '['.
+//   ++c?.[42];
+//        ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:10:8: Error: Can't assign to this.
+//   ++c?.[42];
+//        ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:11:6: Error: Expected an identifier, but got '['.
+// Try inserting an identifier before '['.
+//   c?.[42]?.[0];
+//      ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:11:12: Error: Expected an identifier, but got '['.
+// Try inserting an identifier before '['.
+//   c?.[42]?.[0];
+//            ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:12:6: Error: Expected an identifier, but got '['.
+// Try inserting an identifier before '['.
+//   c?.[42]?.[0] ??= 42;
+//      ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:12:12: Error: Expected an identifier, but got '['.
+// Try inserting an identifier before '['.
+//   c?.[42]?.[0] ??= 42;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:12:16: Error: Can't assign to this.
+//   c?.[42]?.[0] ??= 42;
+//                ^^^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:13:6: Error: Expected an identifier, but got '['.
+// Try inserting an identifier before '['.
+//   c?.[42]?.[0]++;
+//      ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:13:12: Error: Expected an identifier, but got '['.
+// Try inserting an identifier before '['.
+//   c?.[42]?.[0]++;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:13:12: Error: Can't assign to this.
+//   c?.[42]?.[0]++;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:14:8: Error: Expected an identifier, but got '['.
+// Try inserting an identifier before '['.
+//   ++c?.[42]?.[0];
+//        ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:14:14: Error: Expected an identifier, but got '['.
+// Try inserting an identifier before '['.
+//   ++c?.[42]?.[0];
+//              ^
+//
+// pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:14:14: Error: Can't assign to this.
+//   ++c?.[42]?.[0];
+//              ^
+//
+import self as self;
+
+static method main() → dynamic {
+  dynamic c;
+  invalid-expression "pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:7:6: Error: Expected an identifier, but got '['.
+Try inserting an identifier before '['.
+  c?.[42];
+     ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:8:11: Error: Can't assign to this.
+  c?.[42] = 42;
+          ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:9:6: Error: Can't assign to this.
+  c?.[42]++;
+     ^" in invalid-expression "pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:9:6: Error: Expected an identifier, but got '['.
+Try inserting an identifier before '['.
+  c?.[42]++;
+     ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:10:8: Error: Can't assign to this.
+  ++c?.[42];
+       ^" in invalid-expression "pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:10:8: Error: Expected an identifier, but got '['.
+Try inserting an identifier before '['.
+  ++c?.[42];
+       ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:11:12: Error: Expected an identifier, but got '['.
+Try inserting an identifier before '['.
+  c?.[42]?.[0];
+           ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:12:16: Error: Can't assign to this.
+  c?.[42]?.[0] ??= 42;
+               ^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:13:12: Error: Can't assign to this.
+  c?.[42]?.[0]++;
+           ^" in invalid-expression "pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:13:12: Error: Expected an identifier, but got '['.
+Try inserting an identifier before '['.
+  c?.[42]?.[0]++;
+           ^";
+  invalid-expression "pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:14:14: Error: Can't assign to this.
+  ++c?.[42]?.[0];
+             ^" in invalid-expression "pkg/front_end/testcases/nnbd/no_support_for_old_null_aware_index_access_syntax.dart:14:14: Error: Expected an identifier, but got '['.
+Try inserting an identifier before '['.
+  ++c?.[42]?.[0];
+             ^";
+}
diff --git a/pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart.weak.modular.expect
new file mode 100644
index 0000000..ecbc399
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart.weak.modular.expect
@@ -0,0 +1,141 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart:7:5: Error: Field 'topLevelField' should be initialized because its type 'int' doesn't allow null.
+// int topLevelField; // Error.
+//     ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart:10:14: Error: Field 'staticFieldOfA' should be initialized because its type 'int' doesn't allow null.
+//   static int staticFieldOfA; // Error.
+//              ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart:24:14: Error: Field 'staticFieldOfM' should be initialized because its type 'int' doesn't allow null.
+//   static int staticFieldOfM; // Error.
+//              ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart:34:14: Error: Field 'staticFieldOfE' should be initialized because its type 'int' doesn't allow null.
+//   static int staticFieldOfE; // Error.
+//              ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart:12:3: Error: This constructor should initialize field 'fieldOfA' because its type 'int' doesn't allow null.
+//   A.foo();
+//   ^
+// pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart:11:7: Context: 'fieldOfA' is defined here.
+//   int fieldOfA; // Error.
+//       ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart:19:3: Error: This constructor should initialize field 'fieldOfB' because its type 'X' doesn't allow null.
+//   B.foo();
+//   ^
+// pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart:17:5: Context: 'fieldOfB' is defined here.
+//   X fieldOfB; // Error.
+//     ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart:19:3: Error: This constructor should initialize field 'fieldOfB2' because its type 'Y' doesn't allow null.
+//   B.foo();
+//   ^
+// pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart:18:5: Context: 'fieldOfB2' is defined here.
+//   Y fieldOfB2; // Error.
+//     ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart:25:7: Error: Field 'fieldOfM' should be initialized because its type 'int' doesn't allow null.
+//   int fieldOfM; // Error.
+//       ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart:29:5: Error: Field 'fieldOfN' should be initialized because its type 'X' doesn't allow null.
+//   X fieldOfN; // Error.
+//     ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/non_nullable_field_initialization.dart:30:5: Error: Field 'fieldOfN2' should be initialized because its type 'Y' doesn't allow null.
+//   Y fieldOfN2; // Error.
+//     ^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → self::Foo
+    : super core::Object::•()
+    ;
+}
+class A extends core::Object {
+  static field core::int staticFieldOfA = null;
+  field core::int fieldOfA;
+  constructor foo() → self::A
+    : self::A::fieldOfA = null, super core::Object::•()
+    ;
+  constructor bar(core::int fieldOfA) → self::A
+    : self::A::fieldOfA = fieldOfA, super core::Object::•()
+    ;
+}
+class B<X extends core::Object?, Y extends core::Object> extends core::Object {
+  covariant-by-class field self::B::X% fieldOfB;
+  covariant-by-class field self::B::Y fieldOfB2;
+  constructor foo() → self::B<self::B::X%, self::B::Y>
+    : self::B::fieldOfB2 = null, self::B::fieldOfB = null, super core::Object::•()
+    ;
+  constructor bar(self::B::X% fieldOfB, self::B::Y fieldOfB2) → self::B<self::B::X%, self::B::Y>
+    : self::B::fieldOfB = fieldOfB, self::B::fieldOfB2 = fieldOfB2, super core::Object::•()
+    ;
+}
+abstract class M extends core::Object /*isMixinDeclaration*/  {
+  static field core::int staticFieldOfM = null;
+  field core::int fieldOfM = null;
+}
+abstract class N<X extends core::Object?, Y extends core::Object> extends core::Object /*isMixinDeclaration*/  {
+  covariant-by-class field self::N::X% fieldOfN = null;
+  covariant-by-class field self::N::Y fieldOfN2 = null;
+}
+class C<X extends core::Object?, Y extends core::Object> extends core::Object {
+  static field core::int? staticFieldOfX = null;
+  static field core::int staticFieldOfXInitialized = 42;
+  covariant-by-class field self::C::X? fieldOfX = null;
+  field core::int? fieldOfX2 = null;
+  field dynamic fieldOfX3 = null;
+  field Null fieldOfX4 = null;
+  field () →? core::int fieldOfX5 = null;
+  covariant-by-class field self::C::Y? fieldOfX6 = null;
+  late static field core::int lateStaticFieldOfC;
+  late field core::int fieldOfC7;
+  late covariant-by-class field self::C::X% fieldOfC8;
+  late covariant-by-class field self::C::Y fieldOfC9;
+  field core::int fieldOfC10;
+  constructor foo(core::int fieldOfC10) → self::C<self::C::X%, self::C::Y>
+    : self::C::fieldOfC10 = fieldOfC10, super core::Object::•()
+    ;
+  constructor bar(core::int fieldOfC10) → self::C<self::C::X%, self::C::Y>
+    : self::C::fieldOfC10 = fieldOfC10, super core::Object::•()
+    ;
+}
+abstract class L<X extends core::Object?, Y extends core::Object> extends core::Object /*isMixinDeclaration*/  {
+  static field core::int? staticFieldOfL = null;
+  static field core::int staticFieldOfLInitialized = 42;
+  covariant-by-class field self::L::X? fieldOfL = null;
+  field core::int? fieldOfL2 = null;
+  field dynamic fieldOfL3 = null;
+  field Null fieldOfL4 = null;
+  field () →? core::int fieldOfL5 = null;
+  covariant-by-class field self::L::Y? fieldOfL6 = null;
+  late static field core::int lateStaticFieldOfM;
+  late field core::int fieldOfM7;
+  late covariant-by-class field self::L::X% fieldOfM8;
+  late covariant-by-class field self::L::Y fieldOfM9;
+}
+extension P on self::Foo {
+  static field staticFieldOfE = self::P|staticFieldOfE;
+}
+extension Q on self::Foo {
+  static field staticFieldOfQ = self::Q|staticFieldOfQ;
+  static field lateStaticFieldOfQ = self::Q|lateStaticFieldOfQ;
+  static field staticFieldOfQInitialized = self::Q|staticFieldOfQInitialized;
+}
+static field core::int topLevelField;
+static field core::int P|staticFieldOfE;
+static field core::int? nullableTopLevelField;
+late static field core::int lateTopLevelField;
+static field core::int topLevelFieldWithInitializer = 42;
+static field core::int? Q|staticFieldOfQ;
+late static field core::int Q|lateStaticFieldOfQ;
+static field core::int Q|staticFieldOfQInitialized = 42;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/non_nullable_optional.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/non_nullable_optional.dart.weak.modular.expect
new file mode 100644
index 0000000..f03bd13
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/non_nullable_optional.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/non_nullable_optional.dart:9:14: Error: The parameter 'a' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// method1({int a}) {}
+//              ^
+//
+// pkg/front_end/testcases/nnbd/non_nullable_optional.dart:11:14: Error: The parameter 'a' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// method2([int a]) {}
+//              ^
+//
+// pkg/front_end/testcases/nnbd/non_nullable_optional_part.dart:7:14: Error: The parameter 'a' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// method3({int a}) {}
+//              ^
+//
+// pkg/front_end/testcases/nnbd/non_nullable_optional_part.dart:9:14: Error: The parameter 'a' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// method4([int a]) {}
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+
+part non_nullable_optional_part.dart;
+static method main() → dynamic {}
+static method method1({core::int a = #C1}) → dynamic {}
+static method method2([core::int a = #C1]) → dynamic {}
+static method /* from org-dartlang-testcase:///non_nullable_optional_part.dart */ method3({core::int a = #C1}) → dynamic {}
+static method /* from org-dartlang-testcase:///non_nullable_optional_part.dart */ method4([core::int a = #C1]) → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..abcb54d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart.weak.modular.expect
@@ -0,0 +1,220 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:9:10: Error: 'topLevelMethodAndSetter' is already declared in this scope.
+// void set topLevelMethodAndSetter(value) {}
+//          ^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:6:10: Context: Previous declaration of 'topLevelMethodAndSetter'.
+// void set topLevelMethodAndSetter(value) {}
+//          ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:29:12: Error: A class member can't have the same name as the enclosing class.
+// Try renaming the member.
+//   void set Class(value) {}
+//            ^^^^^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart: Error: 'topLevelMethodAndSetter' is exported from both 'pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart' and 'pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart'.
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:9:10: Error: Conflicts with member 'topLevelMethodAndSetter'.
+// void set topLevelMethodAndSetter(value) {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:6:10: Error: Conflicts with member 'topLevelMethodAndSetter'.
+// void set topLevelMethodAndSetter(value) {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:5:1: Error: Conflicts with setter 'topLevelMethodAndSetter'.
+// topLevelMethodAndSetter() {}
+// ^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:13:10: Error: Conflicts with member 'classAndSetter'.
+// void set classAndSetter(value) {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:11:7: Error: Conflicts with setter 'classAndSetter'.
+// class classAndSetter {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:34:12: Error: Conflicts with member 'extensionInstanceMethodAndSetter'.
+//   void set extensionInstanceMethodAndSetter(value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:33:3: Error: Conflicts with setter 'extensionInstanceMethodAndSetter'.
+//   extensionInstanceMethodAndSetter() {}
+//   ^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:37:19: Error: Conflicts with member 'extensionStaticMethodAndSetter'.
+//   static void set extensionStaticMethodAndSetter(value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:36:10: Error: Conflicts with setter 'extensionStaticMethodAndSetter'.
+//   static extensionStaticMethodAndSetter() {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:40:19: Error: Conflicts with member 'extensionInstanceMethodAndStaticSetter'.
+//   static void set extensionInstanceMethodAndStaticSetter(value) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:39:3: Error: Conflicts with setter 'extensionInstanceMethodAndStaticSetter'.
+//   extensionInstanceMethodAndStaticSetter() {}
+//   ^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:43:12: Error: Conflicts with member 'extensionStaticMethodAndInstanceSetter'.
+//   void set extensionStaticMethodAndInstanceSetter(value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:42:10: Error: Conflicts with setter 'extensionStaticMethodAndInstanceSetter'.
+//   static extensionStaticMethodAndInstanceSetter() {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:17:12: Error: 'instanceMethodAndSetter' is already declared in this scope.
+//   void set instanceMethodAndSetter(value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:16:3: Context: Previous declaration of 'instanceMethodAndSetter'.
+//   instanceMethodAndSetter() {}
+//   ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:20:19: Error: 'staticMethodAndSetter' is already declared in this scope.
+//   static void set staticMethodAndSetter(value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:19:10: Context: Previous declaration of 'staticMethodAndSetter'.
+//   static staticMethodAndSetter() {}
+//          ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:23:19: Error: This static member conflicts with an instance member.
+//   static void set instanceMethodAndStaticSetter(value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:22:3: Context: This is the instance member.
+//   instanceMethodAndStaticSetter() {}
+//   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:25:10: Error: This static member conflicts with an instance member.
+//   static staticMethodAndInstanceSetter() {}
+//          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:26:12: Context: This is the instance member.
+//   void set staticMethodAndInstanceSetter(value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:47:3: Error: Setter not found: 'topLevelMethodAndSetter'.
+//   topLevelMethodAndSetter = topLevelMethodAndSetter();
+//   ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:48:22: Error: Couldn't find constructor 'typedefAndSetter'.
+//   typedefAndSetter = typedefAndSetter();
+//                      ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:48:3: Error: Can't assign to a type literal.
+//   typedefAndSetter = typedefAndSetter();
+//   ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:49:3: Error: Can't assign to a type literal.
+//   classAndSetter = classAndSetter();
+//   ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:55:9: Error: Setter not found: 'staticMethodAndSetter'.
+//   Class.staticMethodAndSetter = Class.staticMethodAndSetter();
+//         ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:65:13: Error: Setter not found: 'extensionStaticMethodAndSetter'.
+//   Extension.extensionStaticMethodAndSetter =
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:61:15: Error: The getter 'Class' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'Class'.
+//   c.Class = c.Class;
+//               ^^^^^
+//
+// pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:63:5: Error: The setter 'extensionInstanceFieldAndSetter' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'extensionInstanceFieldAndSetter'.
+//   0.extensionInstanceFieldAndSetter = 0.extensionInstanceMethodAndSetter();
+//     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef typedefAndSetter = () → dynamic;
+class classAndSetter extends core::Object {
+  synthetic constructor •() → self::classAndSetter
+    : super core::Object::•()
+    ;
+}
+class Class extends core::Object {
+  constructor •() → self::Class
+    : super core::Object::•() {}
+  method instanceMethodAndSetter() → dynamic {}
+  set instanceMethodAndSetter(dynamic value) → void {}
+  static method staticMethodAndSetter() → dynamic {}
+  static set staticMethodAndSetter(dynamic value) → void {}
+  method instanceMethodAndStaticSetter() → dynamic {}
+  static set instanceMethodAndStaticSetter(dynamic value) → void {}
+  static method staticMethodAndInstanceSetter() → dynamic {}
+  set staticMethodAndInstanceSetter(dynamic value) → void {}
+  set Class(dynamic value) → void {}
+}
+extension Extension on core::int? {
+  method extensionInstanceMethodAndSetter = self::Extension|extensionInstanceMethodAndSetter;
+  tearoff extensionInstanceMethodAndSetter = self::Extension|get#extensionInstanceMethodAndSetter;
+  static method extensionStaticMethodAndSetter = self::Extension|extensionStaticMethodAndSetter;
+  method extensionInstanceMethodAndStaticSetter = self::Extension|extensionInstanceMethodAndStaticSetter;
+  tearoff extensionInstanceMethodAndStaticSetter = self::Extension|get#extensionInstanceMethodAndStaticSetter;
+  static method extensionStaticMethodAndInstanceSetter = self::Extension|extensionStaticMethodAndInstanceSetter;
+  set extensionInstanceMethodAndSetter = self::Extension|set#extensionInstanceMethodAndSetter;
+  static set extensionStaticMethodAndSetter = set self::Extension|extensionStaticMethodAndSetter;
+  static set extensionInstanceMethodAndStaticSetter = set self::Extension|extensionInstanceMethodAndStaticSetter;
+  set extensionStaticMethodAndInstanceSetter = self::Extension|set#extensionStaticMethodAndInstanceSetter;
+}
+static const field dynamic _exports# = #C1 /*isLegacy*/;
+static method topLevelMethodAndSetter() → dynamic {}
+static set topLevelMethodAndSetter(dynamic value) → void {}
+static set classAndSetter(dynamic value) → void {}
+static method Extension|extensionInstanceMethodAndSetter(lowered final core::int? #this) → dynamic {}
+static method Extension|get#extensionInstanceMethodAndSetter(lowered final core::int? #this) → () → dynamic
+  return () → dynamic => self::Extension|extensionInstanceMethodAndSetter(#this);
+static method Extension|set#extensionInstanceMethodAndSetter(lowered final core::int? #this, dynamic value) → void {}
+static method Extension|extensionStaticMethodAndSetter() → dynamic {}
+static set Extension|extensionStaticMethodAndSetter(dynamic value) → void {}
+static method Extension|extensionInstanceMethodAndStaticSetter(lowered final core::int? #this) → dynamic {}
+static method Extension|get#extensionInstanceMethodAndStaticSetter(lowered final core::int? #this) → () → dynamic
+  return () → dynamic => self::Extension|extensionInstanceMethodAndStaticSetter(#this);
+static set Extension|extensionInstanceMethodAndStaticSetter(dynamic value) → void {}
+static method Extension|extensionStaticMethodAndInstanceSetter() → dynamic {}
+static method Extension|set#extensionStaticMethodAndInstanceSetter(lowered final core::int? #this, dynamic value) → void {}
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:47:3: Error: Setter not found: 'topLevelMethodAndSetter'.
+  topLevelMethodAndSetter = topLevelMethodAndSetter();
+  ^^^^^^^^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:48:3: Error: Can't assign to a type literal.
+  typedefAndSetter = typedefAndSetter();
+  ^^^^^^^^^^^^^^^^";
+  invalid-expression "pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:49:3: Error: Can't assign to a type literal.
+  classAndSetter = classAndSetter();
+  ^^^^^^^^^^^^^^";
+  self::Class c = new self::Class::•();
+  c.{self::Class::instanceMethodAndSetter} = c.{self::Class::instanceMethodAndSetter}(){() → dynamic};
+  invalid-expression "pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:55:9: Error: Setter not found: 'staticMethodAndSetter'.
+  Class.staticMethodAndSetter = Class.staticMethodAndSetter();
+        ^^^^^^^^^^^^^^^^^^^^^";
+  c.{self::Class::staticMethodAndInstanceSetter} = self::Class::staticMethodAndInstanceSetter();
+  self::Class::instanceMethodAndStaticSetter = c.{self::Class::instanceMethodAndStaticSetter}(){() → dynamic};
+  c.{self::Class::Class} = invalid-expression "pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:61:15: Error: The getter 'Class' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'Class'.
+  c.Class = c.Class;
+              ^^^^^" in c{<unresolved>}.Class;
+  invalid-expression "pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:63:5: Error: The setter 'extensionInstanceFieldAndSetter' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'extensionInstanceFieldAndSetter'.
+  0.extensionInstanceFieldAndSetter = 0.extensionInstanceMethodAndSetter();
+    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^" in 0{<unresolved>}.extensionInstanceFieldAndSetter = self::Extension|extensionInstanceMethodAndSetter(0);
+  invalid-expression "pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart:65:13: Error: Setter not found: 'extensionStaticMethodAndSetter'.
+  Extension.extensionStaticMethodAndSetter =
+            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^";
+  self::Extension|set#extensionStaticMethodAndInstanceSetter(0, self::Extension|extensionStaticMethodAndInstanceSetter());
+  self::Extension|extensionInstanceMethodAndStaticSetter = self::Extension|extensionInstanceMethodAndStaticSetter(0);
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = "{\"topLevelMethodAndSetter\":\"'topLevelMethodAndSetter' is exported from both 'pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart' and 'pkg/front_end/testcases/nnbd/nonfield_vs_setter.dart'.\"}"
+}
diff --git a/pkg/front_end/testcases/nnbd/not_definitely_unassigned_late_local_variables.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/not_definitely_unassigned_late_local_variables.dart.weak.modular.expect
new file mode 100644
index 0000000..682b905
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/not_definitely_unassigned_late_local_variables.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class A<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+  abstract method baz() → self::A::T%;
+  method bar(covariant-by-class self::A::T% value) → dynamic {}
+  method barInt(core::int value) → dynamic {}
+  method foo() → dynamic {
+    late self::A::T% value;
+    late core::int intValue;
+    () → Null result = () → Null {
+      this.{self::A::bar}(value){(self::A::T%) → dynamic};
+      this.{self::A::barInt}(intValue){(core::int) → dynamic};
+    };
+    (() → Null {
+      value = this.{self::A::baz}(){() → self::A::T%};
+      intValue = 42;
+    })(){() → Null};
+    return result;
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/null_access.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/null_access.dart.weak.modular.expect
new file mode 100644
index 0000000..e32613c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/null_access.dart.weak.modular.expect
@@ -0,0 +1,204 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:24:3: Error: Operator 'unary-' cannot be called on 'int?' because it is potentially null.
+//   -nullableInt; // error
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:25:15: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+//   nullableInt + 2; // error
+//               ^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:26:16: Error: Operator '[]' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+//   nullableClass[nonNullableInt]; // error
+//                ^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:27:16: Error: Operator '[]=' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+//   nullableClass[nonNullableInt] = nonNullableInt; // error
+//                ^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:28:16: Error: Operator '[]' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+//   nullableClass[nonNullableInt] += nonNullableInt; // error
+//                ^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:28:16: Error: Operator '[]=' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+//   nullableClass[nonNullableInt] += nonNullableInt; // error
+//                ^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:29:29: Error: Operator '[]' cannot be called on 'NullableIndexClass?' because it is potentially null.
+//  - 'NullableIndexClass' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+//   nullableNullableIndexClass[nonNullableInt] ??= nonNullableInt; // error
+//                             ^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:29:29: Error: Operator '[]=' cannot be called on 'NullableIndexClass?' because it is potentially null.
+//  - 'NullableIndexClass' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+//   nullableNullableIndexClass[nonNullableInt] ??= nonNullableInt; // error
+//                             ^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:37:17: Error: Property 'nonNullableField' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+// Try accessing using ?. instead.
+//   nullableClass.nonNullableField; // error
+//                 ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:38:17: Error: Property 'nonNullableField' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+// Try accessing using ?. instead.
+//   nullableClass.nonNullableField = 2; // error
+//                 ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:39:17: Error: Property 'nonNullableField' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+// Try accessing using ?. instead.
+//   nullableClass.nonNullableField += 2; // error
+//                 ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:48:34: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+//   nonNullableClass.nullableField += 2; // error
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:48:34: Error: A value of type 'num' can't be assigned to a variable of type 'int?'.
+//   nonNullableClass.nullableField += 2; // error
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:49:32: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+//   nullableClass?.nullableField += 2; // error
+//                                ^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:49:32: Error: A value of type 'num' can't be assigned to a variable of type 'int?'.
+//   nullableClass?.nullableField += 2; // error
+//                                ^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:54:35: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   nullableClass?.nonNullableClass.nonNullableField ??= 0; // ok
+//                                   ^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:57:16: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+// Try calling using ?.call instead.
+//   nullableClass(); // error
+//                ^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:59:3: Warning: Operand of null-aware operation '?.' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+//   nonNullableClass?.nonNullableClass(); // ok
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_access.dart:60:3: Warning: Operand of null-aware operation '?.' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+//   nonNullableClass?.nonNullableClass.nonNullableClass(); // ok
+//   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int nonNullableField = 0;
+  field core::int? nullableField = null;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  operator [](core::int key) → core::int
+    return key;
+  operator []=(core::int key, core::int value) → void {}
+  get nonNullableClass() → self::Class
+    return this;
+  method call() → self::Class
+    return this;
+  get nonNullableNullableIndexClass() → self::NullableIndexClass
+    return new self::NullableIndexClass::•();
+}
+class NullableIndexClass extends core::Object {
+  synthetic constructor •() → self::NullableIndexClass
+    : super core::Object::•()
+    ;
+  operator [](core::int key) → core::int?
+    return key;
+  operator []=(core::int key, core::int value) → void {}
+}
+static method main() → dynamic {}
+static method errors(self::Class? nullableClass, self::Class nonNullableClass, core::int? nullableInt, core::int nonNullableInt, self::NullableIndexClass? nullableNullableIndexClass) → dynamic {
+  invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:24:3: Error: Operator 'unary-' cannot be called on 'int?' because it is potentially null.
+  -nullableInt; // error
+  ^" in nullableInt.{core::int::unary-}(){() → core::int};
+  invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:25:15: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+  nullableInt + 2; // error
+              ^" in nullableInt.{core::num::+}(2){(core::num) → core::num};
+  invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:26:16: Error: Operator '[]' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+  nullableClass[nonNullableInt]; // error
+               ^" in nullableClass.{self::Class::[]}{<nullable>}.(nonNullableInt){(core::int) → core::int};
+  invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:27:16: Error: Operator '[]=' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+  nullableClass[nonNullableInt] = nonNullableInt; // error
+               ^" in nullableClass.{self::Class::[]=}{<nullable>}.(nonNullableInt, nonNullableInt){(core::int, core::int) → void};
+  let final self::Class? #t1 = nullableClass in let final core::int #t2 = nonNullableInt in invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:28:16: Error: Operator '[]=' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+  nullableClass[nonNullableInt] += nonNullableInt; // error
+               ^" in #t1.{self::Class::[]=}{<nullable>}.(#t2, invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:28:16: Error: Operator '[]' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+  nullableClass[nonNullableInt] += nonNullableInt; // error
+               ^" in #t1.{self::Class::[]}{<nullable>}.(#t2){(core::int) → core::int}.{core::num::+}(nonNullableInt){(core::num) → core::int}){(core::int, core::int) → void};
+  let final self::NullableIndexClass? #t3 = nullableNullableIndexClass in let final core::int #t4 = nonNullableInt in invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:29:29: Error: Operator '[]' cannot be called on 'NullableIndexClass?' because it is potentially null.
+ - 'NullableIndexClass' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+  nullableNullableIndexClass[nonNullableInt] ??= nonNullableInt; // error
+                            ^" in #t3.{self::NullableIndexClass::[]}{<nullable>}.(#t4){(core::int) → core::int?} == null ?{core::int} invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:29:29: Error: Operator '[]=' cannot be called on 'NullableIndexClass?' because it is potentially null.
+ - 'NullableIndexClass' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+  nullableNullableIndexClass[nonNullableInt] ??= nonNullableInt; // error
+                            ^" in #t3.{self::NullableIndexClass::[]=}{<nullable>}.(#t4, nonNullableInt){(core::int, core::int) → void} : null;
+  let final self::Class? #t5 = nullableClass in #t5 == null ?{core::int?} null : #t5{self::Class}.{self::Class::nonNullableClass}{self::Class}.{self::Class::[]}(nonNullableInt){(core::int) → core::int};
+  let final self::Class? #t6 = nullableClass in #t6 == null ?{core::int?} null : #t6{self::Class}.{self::Class::nonNullableClass}{self::Class}.{self::Class::[]=}(nonNullableInt, nonNullableInt){(core::int, core::int) → void};
+  let final self::Class? #t7 = nullableClass in #t7 == null ?{core::int?} null : let final self::Class #t8 = #t7{self::Class}.{self::Class::nonNullableClass}{self::Class} in let final core::int #t9 = nonNullableInt in #t8.{self::Class::[]=}(#t9, #t8.{self::Class::[]}(#t9){(core::int) → core::int}.{core::num::+}(nonNullableInt){(core::num) → core::int}){(core::int, core::int) → void};
+  let final self::Class? #t10 = nullableClass in #t10 == null ?{core::int?} null : let final self::NullableIndexClass #t11 = #t10{self::Class}.{self::Class::nonNullableNullableIndexClass}{self::NullableIndexClass} in let final core::int #t12 = nonNullableInt in #t11.{self::NullableIndexClass::[]}(#t12){(core::int) → core::int?} == null ?{core::int} #t11.{self::NullableIndexClass::[]=}(#t12, nonNullableInt){(core::int, core::int) → void} : null;
+  invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:37:17: Error: Property 'nonNullableField' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+Try accessing using ?. instead.
+  nullableClass.nonNullableField; // error
+                ^^^^^^^^^^^^^^^^" in nullableClass.{self::Class::nonNullableField}{<nullable>}.{core::int};
+  invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:38:17: Error: Property 'nonNullableField' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+Try accessing using ?. instead.
+  nullableClass.nonNullableField = 2; // error
+                ^^^^^^^^^^^^^^^^" in nullableClass.{self::Class::nonNullableField}{<nullable>}. = 2;
+  let final self::Class? #t13 = nullableClass in invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:39:17: Error: Property 'nonNullableField' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+Try accessing using ?. instead.
+  nullableClass.nonNullableField += 2; // error
+                ^^^^^^^^^^^^^^^^" in #t13.{self::Class::nonNullableField}{<nullable>}. = invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:39:17: Error: Property 'nonNullableField' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+Try accessing using ?. instead.
+  nullableClass.nonNullableField += 2; // error
+                ^^^^^^^^^^^^^^^^" in #t13.{self::Class::nonNullableField}{<nullable>}.{core::int}.{core::num::+}(2){(core::num) → core::int};
+  let final self::Class? #t14 = nullableClass in #t14 == null ?{core::int?} null : #t14{self::Class}.{self::Class::nonNullableField}{core::int};
+  let final self::Class? #t15 = nullableClass in #t15 == null ?{core::int?} null : #t15{self::Class}.{self::Class::nonNullableField} = 2;
+  let final self::Class? #t16 = nullableClass in #t16 == null ?{core::int?} null : #t16.{self::Class::nonNullableField} = #t16.{self::Class::nonNullableField}{core::int}.{core::num::+}(2){(core::num) → core::int};
+  let final self::Class? #t17 = nullableClass in #t17 == null ?{core::int?} null : #t17{self::Class}.{self::Class::nonNullableClass}{self::Class}.{self::Class::nonNullableField}{core::int};
+  let final self::Class? #t18 = nullableClass in #t18 == null ?{core::int?} null : #t18{self::Class}.{self::Class::nonNullableClass}{self::Class}.{self::Class::nonNullableField} = 2;
+  let final self::Class #t19 = nonNullableClass in #t19.{self::Class::nullableField} = invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:48:34: Error: A value of type 'num' can't be assigned to a variable of type 'int?'.
+  nonNullableClass.nullableField += 2; // error
+                                 ^" in invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:48:34: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+  nonNullableClass.nullableField += 2; // error
+                                 ^" in #t19.{self::Class::nullableField}{core::int?}.{core::num::+}(2){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int?;
+  let final self::Class? #t20 = nullableClass in #t20 == null ?{core::num?} null : #t20.{self::Class::nullableField} = invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:49:32: Error: A value of type 'num' can't be assigned to a variable of type 'int?'.
+  nullableClass?.nullableField += 2; // error
+                               ^" in invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:49:32: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+  nullableClass?.nullableField += 2; // error
+                               ^" in #t20.{self::Class::nullableField}{core::int?}.{core::num::+}(2){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int?;
+  let final self::Class? #t21 = nullableClass in #t21 == null ?{core::int?} null : #t21.{self::Class::nonNullableField}{core::int} == null ?{core::int} #t21.{self::Class::nonNullableField} = 0 : null;
+  let final self::Class? #t22 = nullableClass in #t22 == null ?{core::int?} null : #t22.{self::Class::nullableField}{core::int?} == null ?{core::int} #t22.{self::Class::nullableField} = 0 : null;
+  let final self::Class? #t23 = nullableClass in #t23 == null ?{core::int?} null : let final self::Class #t24 = #t23{self::Class}.{self::Class::nonNullableClass}{self::Class} in #t24.{self::Class::nonNullableField}{core::int} == null ?{core::int} #t24.{self::Class::nonNullableField} = 0 : null;
+  let final self::Class? #t25 = nullableClass in #t25 == null ?{core::int?} null : let final self::Class #t26 = #t25{self::Class}.{self::Class::nonNullableClass}{self::Class} in #t26.{self::Class::nullableField}{core::int?} == null ?{core::int} #t26.{self::Class::nullableField} = 0 : null;
+  invalid-expression "pkg/front_end/testcases/nnbd/null_access.dart:57:16: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/null_access.dart'.
+Try calling using ?.call instead.
+  nullableClass(); // error
+               ^" in nullableClass.{self::Class::call}{<nullable>}.(){() → self::Class};
+  nonNullableClass.{self::Class::call}(){() → self::Class};
+  let final self::Class #t27 = nonNullableClass in #t27 == null ?{self::Class?} null : #t27.{self::Class::nonNullableClass}{self::Class}.{self::Class::call}(){() → self::Class};
+  let final self::Class #t28 = nonNullableClass in #t28 == null ?{self::Class?} null : #t28.{self::Class::nonNullableClass}{self::Class}.{self::Class::nonNullableClass}{self::Class}.{self::Class::call}(){() → self::Class};
+}
diff --git a/pkg/front_end/testcases/nnbd/null_aware_chain.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/null_aware_chain.dart.weak.modular.expect
new file mode 100644
index 0000000..ce3973c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/null_aware_chain.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field self::Class? field;
+  constructor •([self::Class? field = #C1]) → self::Class
+    : self::Class::field = field, super core::Object::•()
+    ;
+  get getter1() → self::Class
+    return this;
+  get getter2() → self::Class?
+    return this.{self::Class::field}{self::Class?};
+}
+static method main() → dynamic {
+  self::Class? c = new self::Class::•() as{ForNonNullableByDefault} self::Class?;
+  let final self::Class? #t1 = c in #t1 == null ?{self::Class?} null : let final self::Class? #t2 = #t1{self::Class}.{self::Class::getter1}{self::Class}.{self::Class::getter2}{self::Class?} in #t2 == null ?{self::Class?} null : let final self::Class? #t3 = #t2{self::Class}.{self::Class::getter1}{self::Class}.{self::Class::getter2}{self::Class?} in #t3 == null ?{self::Class?} null : #t3{self::Class}.{self::Class::field} = c{self::Class};
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/null_aware_static_access.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/null_aware_static_access.dart.weak.modular.expect
new file mode 100644
index 0000000..9811bce
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/null_aware_static_access.dart.weak.modular.expect
@@ -0,0 +1,98 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/null_aware_static_access.dart:17:3: Warning: The class 'C' cannot be null.
+// Try replacing '?.' with '.'
+//   C?.staticMember;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_aware_static_access.dart:18:3: Warning: The class 'C' cannot be null.
+// Try replacing '?.' with '.'
+//   C?.staticMember;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_aware_static_access.dart:19:3: Warning: The class 'C' cannot be null.
+// Try replacing '?.' with '.'
+//   C?.staticMember = 42;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_aware_static_access.dart:21:3: Warning: The class 'C' cannot be null.
+// Try replacing '?.' with '.'
+//   C?.staticMember.isEven;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_aware_static_access.dart:22:3: Warning: The class 'C' cannot be null.
+// Try replacing '?.' with '.'
+//   C?.staticMember.toString();
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_aware_static_access.dart:23:3: Warning: The class 'C' cannot be null.
+// Try replacing '?.' with '.'
+//   C?.property[0];
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_aware_static_access.dart:24:3: Warning: The class 'C' cannot be null.
+// Try replacing '?.' with '.'
+//   C?.property[0] = 0;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_aware_static_access.dart:25:3: Warning: The class 'C' cannot be null.
+// Try replacing '?.' with '.'
+//   C?.property2[0] ??= 0;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_aware_static_access.dart:26:3: Warning: The class 'C' cannot be null.
+// Try replacing '?.' with '.'
+//   C?.staticMember2 ??= 42;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_aware_static_access.dart:27:3: Warning: The class 'C' cannot be null.
+// Try replacing '?.' with '.'
+//   C?.staticMember += 2;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_aware_static_access.dart:28:3: Warning: The class 'C' cannot be null.
+// Try replacing '?.' with '.'
+//   C?.staticMember++;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_aware_static_access.dart:29:5: Warning: The class 'C' cannot be null.
+// Try replacing '?.' with '.'
+//   --C?.staticMember;
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  static get staticMember() → core::int
+    return 0;
+  static set staticMember(core::int value) → void {}
+  static get staticMember2() → core::int?
+    return 0;
+  static set staticMember2(core::int? value) → void {}
+  static method staticMethod() → void {}
+  static get property() → core::List<core::int>
+    return <core::int>[0];
+  static get property2() → core::Map<core::int, core::int?>
+    return <core::int, core::int?>{};
+}
+static method main() → void {
+  self::C::staticMember;
+  self::C::staticMember;
+  self::C::staticMember = 42;
+  self::C::staticMethod();
+  self::C::staticMember.{core::int::isEven}{core::bool};
+  self::C::staticMember.{core::int::toString}(){() → core::String};
+  self::C::property.{core::List::[]}(0){(core::int) → core::int};
+  self::C::property.{core::List::[]=}(0, 0){(core::int, core::int) → void};
+  let final core::Map<core::int, core::int?> #t1 = self::C::property2 in let final core::int #t2 = 0 in #t1.{core::Map::[]}(#t2){(core::Object?) → core::int?} == null ?{core::int} #t1.{core::Map::[]=}(#t2, 0){(core::int, core::int?) → void} : null;
+  self::C::staticMember2 == null ?{core::int} self::C::staticMember2 = 42 : null;
+  self::C::staticMember = self::C::staticMember.{core::num::+}(2){(core::num) → core::int};
+  self::C::staticMember = self::C::staticMember.{core::num::+}(1){(core::num) → core::int};
+  self::C::staticMember = self::C::staticMember.{core::num::-}(1){(core::num) → core::int};
+}
diff --git a/pkg/front_end/testcases/nnbd/null_aware_this_access.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/null_aware_this_access.dart.weak.modular.expect
new file mode 100644
index 0000000..aac887e
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/null_aware_this_access.dart.weak.modular.expect
@@ -0,0 +1,170 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:12:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?.m1;
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:13:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?.m1 = 42;
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:14:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?.method();
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:15:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?.property.m1;
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:16:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?.property.method();
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:17:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?[0];
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:18:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?[0] = 0;
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:19:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?[0] ??= 0;
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:20:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?.property[0];
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:21:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?.property[0] = 0;
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:22:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?.property[0] ??= 0;
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:23:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?.m1 ??= 42;
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:24:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?.m2 += 2;
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:25:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?.m2++;
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:26:7: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     --this?.m2;
+//       ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:27:5: Warning: Operand of null-aware operation '??' has type 'C' which excludes null.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd/null_aware_this_access.dart'.
+//     this ?? new C();
+//     ^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:41:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?[0];
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:42:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?[0] = 0;
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:43:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?[0] += 0;
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:44:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?.property[0];
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:45:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?.property[0] = 0;
+//     ^^^^
+//
+// pkg/front_end/testcases/nnbd/null_aware_this_access.dart:46:5: Warning: The receiver 'this' cannot be null.
+// Try replacing '?.' with '.'
+//     this?.property[0] += 0;
+//     ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field core::int? m1 = null;
+  field core::int m2 = 0;
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  get property() → self::C
+    return this;
+  method test() → dynamic {
+    this.{self::C::m1}{core::int?};
+    this.{self::C::m1} = 42;
+    this.{self::C::method}(){() → dynamic};
+    this.{self::C::property}{self::C}.{self::C::m1}{core::int?};
+    this.{self::C::property}{self::C}.{self::C::method}(){() → dynamic};
+    this.{self::C::[]}(0){(core::int) → core::int?};
+    this.{self::C::[]=}(0, 0){(core::int, core::int) → void};
+    let final core::int #t1 = 0 in this.{self::C::[]}(#t1){(core::int) → core::int?} == null ?{core::int} this.{self::C::[]=}(#t1, 0){(core::int, core::int) → void} : null;
+    this.{self::C::property}{self::C}.{self::C::[]}(0){(core::int) → core::int?};
+    this.{self::C::property}{self::C}.{self::C::[]=}(0, 0){(core::int, core::int) → void};
+    let final self::C #t2 = this.{self::C::property}{self::C} in let final core::int #t3 = 0 in #t2.{self::C::[]}(#t3){(core::int) → core::int?} == null ?{core::int} #t2.{self::C::[]=}(#t3, 0){(core::int, core::int) → void} : null;
+    this.{self::C::m1}{core::int?} == null ?{core::int} this.{self::C::m1} = 42 : null;
+    this.{self::C::m2} = this.{self::C::m2}{core::int}.{core::num::+}(2){(core::num) → core::int};
+    this.{self::C::m2} = this.{self::C::m2}{core::int}.{core::num::+}(1){(core::num) → core::int};
+    this.{self::C::m2} = this.{self::C::m2}{core::int}.{core::num::-}(1){(core::num) → core::int};
+    this;
+  }
+  operator [](core::int index) → core::int?
+    return 0;
+  operator []=(core::int index, core::int value) → void {}
+  method method() → dynamic {}
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D
+    : super core::Object::•()
+    ;
+  get property() → self::D
+    return this;
+  method test() → dynamic {
+    this.{self::D::[]}(0){(core::int) → core::int};
+    this.{self::D::[]=}(0, 0){(core::int, core::int) → void};
+    let final core::int #t4 = 0 in this.{self::D::[]=}(#t4, this.{self::D::[]}(#t4){(core::int) → core::int}.{core::num::+}(0){(core::num) → core::int}){(core::int, core::int) → void};
+    this.{self::D::property}{self::D}.{self::D::[]}(0){(core::int) → core::int};
+    this.{self::D::property}{self::D}.{self::D::[]=}(0, 0){(core::int, core::int) → void};
+    let final self::D #t5 = this.{self::D::property}{self::D} in let final core::int #t6 = 0 in #t5.{self::D::[]=}(#t6, #t5.{self::D::[]}(#t6){(core::int) → core::int}.{core::num::+}(0){(core::num) → core::int}){(core::int, core::int) → void};
+  }
+  operator [](core::int index) → core::int
+    return 0;
+  operator []=(core::int index, core::int value) → void {}
+}
+static method main() → dynamic {
+  new self::C::•().{self::C::test}(){() → dynamic};
+  new self::D::•().{self::D::test}(){() → dynamic};
+}
diff --git a/pkg/front_end/testcases/nnbd/null_check.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/null_check.dart.weak.modular.expect
new file mode 100644
index 0000000..bbfe2d7
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/null_check.dart.weak.modular.expect
@@ -0,0 +1,117 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:14:3: Warning: Operand of null-aware operation '!' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_check.dart'.
+//   c!.field;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:15:3: Warning: Operand of null-aware operation '!' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_check.dart'.
+//   c!.field = 42;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:16:3: Warning: Operand of null-aware operation '!' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_check.dart'.
+//   c!.method;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:17:3: Warning: Operand of null-aware operation '!' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_check.dart'.
+//   c!.method();
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:18:3: Warning: Operand of null-aware operation '!' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_check.dart'.
+//   c!.field!.toString();
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:19:3: Warning: Operand of null-aware operation '!' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_check.dart'.
+//   c!.method()!.toString();
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:20:3: Warning: Operand of null-aware operation '!' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_check.dart'.
+//   c! + c;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:21:3: Warning: Operand of null-aware operation '!' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_check.dart'.
+//   c! + c!;
+//   ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:21:8: Warning: Operand of null-aware operation '!' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_check.dart'.
+//   c! + c!;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:22:7: Warning: Operand of null-aware operation '!' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_check.dart'.
+//   c + c!;
+//       ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:23:6: Warning: Operand of null-aware operation '!' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/null_check.dart'.
+//   (c + c)!;
+//      ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:26:10: Warning: Operand of null-aware operation '!' has type 'bool' which excludes null.
+//   !o! ? !o! : !!o!!;
+//          ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:26:17: Warning: Operand of null-aware operation '!' has type 'bool' which excludes null.
+//   !o! ? !o! : !!o!!;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:26:18: Warning: Operand of null-aware operation '!' has type 'bool' which excludes null.
+//   !o! ? !o! : !!o!!;
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:27:5: Warning: Operand of null-aware operation '!' has type 'bool' which excludes null.
+//   !(o!) ? (!o)! : (!(!o)!)!;
+//     ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:27:12: Warning: Operand of null-aware operation '!' has type 'bool' which excludes null.
+//   !(o!) ? (!o)! : (!(!o)!)!;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:27:22: Warning: Operand of null-aware operation '!' has type 'bool' which excludes null.
+//   !(o!) ? (!o)! : (!(!o)!)!;
+//                      ^
+//
+// pkg/front_end/testcases/nnbd/null_check.dart:27:20: Warning: Operand of null-aware operation '!' has type 'bool' which excludes null.
+//   !(o!) ? (!o)! : (!(!o)!)!;
+//                    ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int? field = null;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  method method() → core::int?
+    return this.{self::Class::field}{core::int?};
+  operator +(self::Class other) → self::Class
+    return new self::Class::•();
+}
+static method main() → dynamic {
+  self::Class? c = new self::Class::•() as{ForNonNullableByDefault} self::Class?;
+  c!;
+  c{self::Class}!.{self::Class::field}{core::int?};
+  c{self::Class}!.{self::Class::field} = 42;
+  c{self::Class}!.{self::Class::method}{() → core::int?};
+  c{self::Class}!.{self::Class::method}(){() → core::int?};
+  c{self::Class}!.{self::Class::field}{core::int?}!.{core::int::toString}(){() → core::String};
+  c{self::Class}!.{self::Class::method}(){() → core::int?}!.{core::int::toString}(){() → core::String};
+  c{self::Class}!.{self::Class::+}(c{self::Class}){(self::Class) → self::Class};
+  c{self::Class}!.{self::Class::+}(c{self::Class}!){(self::Class) → self::Class};
+  c{self::Class}.{self::Class::+}(c{self::Class}!){(self::Class) → self::Class};
+  c{self::Class}.{self::Class::+}(c{self::Class}){(self::Class) → self::Class}!;
+  core::bool? o = true as{ForNonNullableByDefault} core::bool?;
+  !o! ?{core::bool} !o{core::bool}! : !!o{core::bool}!!;
+  !o{core::bool}! ?{core::bool} (!o{core::bool})! : (!(!o{core::bool})!)!;
+}
diff --git a/pkg/front_end/testcases/nnbd/null_check_context.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/null_check_context.dart.weak.modular.expect
new file mode 100644
index 0000000..010a0ff
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/null_check_context.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  abstract method bar<T extends core::Object? = dynamic>() → self::A::bar::T%;
+  method foo() → core::String
+    return this.{self::A::bar}<core::String?>(){() → core::String?}!;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/null_shorting.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/null_shorting.dart.weak.modular.expect
new file mode 100644
index 0000000..6be85bf
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/null_shorting.dart.weak.modular.expect
@@ -0,0 +1,269 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/null_shorting.dart:87:47: Error: Property 'nullable1' cannot be accessed on 'Class1?' because it is potentially null.
+//  - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting.dart'.
+// Try accessing using ?. instead.
+//   throws(() => (n1?.nullable1 = new Class1()).nullable1);
+//                                               ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/null_shorting.dart:88:43: Error: Property 'nullable1' cannot be accessed on 'Class1?' because it is potentially null.
+//  - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting.dart'.
+// Try accessing using ?. instead.
+//   throws(() => (n1?.nonNullable1Method()).nullable1);
+//                                           ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/null_shorting.dart:220:33: Error: Operator '+' cannot be called on 'Class1?' because it is potentially null.
+//  - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting.dart'.
+//   throws(() => n1?.nonNullable1 + 0);
+//                                 ^
+//
+// pkg/front_end/testcases/nnbd/null_shorting.dart:221:16: Error: Operator 'unary-' cannot be called on 'Class1?' because it is potentially null.
+//  - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting.dart'.
+//   throws(() => -n1?.nonNullable1);
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+  get property() → self::Class1?
+    return null;
+  set property(self::Class1? value) → void {}
+  get property1() → self::Class1
+    return new self::Class1::•();
+  get property2() → self::Class2
+    return new self::Class2::•();
+  get nullable1() → self::Class1?
+    return this.{self::Class1::property1}{self::Class1};
+  set nullable1(self::Class1? value) → void {
+    this.{self::Class1::property} = value;
+  }
+  method nonNullable1Method() → self::Class1
+    return this.{self::Class1::nonNullable1}{self::Class1};
+  operator [](self::Class1? key) → self::Class1?
+    return this.{self::Class1::nullable1}{self::Class1?};
+  operator []=(self::Class1? key, self::Class1? value) → void {
+    this.{self::Class1::property} = value;
+  }
+  operator +(core::int value) → self::Class1?
+    return this.{self::Class1::nullable1}{self::Class1?};
+  operator unary-() → self::Class1?
+    return this.{self::Class1::nullable1}{self::Class1?};
+  get nonNullable1() → self::Class1
+    return this.{self::Class1::property1}{self::Class1};
+  get nonNullable2() → self::Class2
+    return this.{self::Class1::property2}{self::Class2};
+}
+class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2
+    : super core::Object::•()
+    ;
+  get property() → self::Class2
+    return this;
+  set property(self::Class2 value) → void {}
+  method nonNullable2Method() → self::Class2
+    return this.{self::Class2::nonNullable2}{self::Class2};
+  operator [](self::Class2? key) → self::Class2
+    return this.{self::Class2::property}{self::Class2};
+  operator []=(self::Class2? key, self::Class2? value) → void
+    return this.{self::Class2::property}{self::Class2};
+  operator +(core::int value) → self::Class2
+    return this.{self::Class2::property}{self::Class2};
+  operator unary-() → self::Class2
+    return this.{self::Class2::property}{self::Class2};
+  get nonNullable2() → self::Class2
+    return this.{self::Class2::property}{self::Class2};
+  set nonNullable2(self::Class2 value) → void {
+    this.{self::Class2::property} = value;
+  }
+}
+class Class3 extends core::Object {
+  synthetic constructor •() → self::Class3
+    : super core::Object::•()
+    ;
+  get property() → self::Class2?
+    return null;
+  operator [](self::Class3? key) → self::Class2?
+    return this.{self::Class3::property}{self::Class2?};
+}
+static method main() → dynamic {
+  self::propertyAccess(null);
+  self::indexAccess(null, null, null);
+  self::operatorAccess(null, null);
+  self::ifNull(null);
+}
+static method propertyAccess(self::Class1? n1) → void {
+  self::Class1? nullable1 = n1;
+  let final self::Class1? #t1 = n1 in #t1 == null ?{self::Class1?} null : #t1{self::Class1}.{self::Class1::nullable1}{self::Class1?};
+  let final self::Class1? #t2 = n1 in #t2 == null ?{self::Class1?} null : #t2{self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  nullable1 = let final self::Class1? #t3 = n1 in #t3 == null ?{self::Class1?} null : #t3{self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t4 = n1 in #t4 == null ?{self::Class1?} null : #t4{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t5 = n1 in #t5 == null ?{self::Class1?} null : #t5{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1}{self::Class1?};
+  let final self::Class1? #t6 = n1 in #t6 == null ?{self::Class1?} null : let final self::Class1? #t7 = #t6{self::Class1}.{self::Class1::nullable1}{self::Class1?} in #t7 == null ?{self::Class1?} null : #t7{self::Class1}.{self::Class1::nullable1}{self::Class1?};
+  let final self::Class1? #t8 = n1 in #t8 == null ?{self::Class1?} null : let final self::Class1? #t9 = #t8{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1}{self::Class1?} in #t9 == null ?{self::Class1?} null : #t9{self::Class1}.{self::Class1::nullable1}{self::Class1?};
+  let final self::Class1? #t10 = n1 in #t10 == null ?{self::Class1?} null : #t10{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t11 = n1 in #t11 == null ?{self::Class1?} null : let final self::Class1? #t12 = #t11{self::Class1}.{self::Class1::nullable1}{self::Class1?} in #t12 == null ?{self::Class1?} null : #t12{self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t13 = n1 in #t13 == null ?{self::Class1?} null : let final self::Class1? #t14 = #t13{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1}{self::Class1?} in #t14 == null ?{self::Class1?} null : #t14{self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t15 = let final self::Class1? #t16 = n1 in #t16 == null ?{self::Class1?} null : #t16{self::Class1}.{self::Class1::nullable1}{self::Class1?} in #t15 == null ?{self::Class1?} null : #t15{self::Class1}.{self::Class1::nullable1}{self::Class1?};
+  self::throws(() → void => invalid-expression "pkg/front_end/testcases/nnbd/null_shorting.dart:87:47: Error: Property 'nullable1' cannot be accessed on 'Class1?' because it is potentially null.
+ - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting.dart'.
+Try accessing using ?. instead.
+  throws(() => (n1?.nullable1 = new Class1()).nullable1);
+                                              ^^^^^^^^^" in (let final self::Class1? #t17 = n1 in #t17 == null ?{self::Class1?} null : #t17{self::Class1}.{self::Class1::nullable1} = new self::Class1::•()).{self::Class1::nullable1}{<nullable>}.{self::Class1?});
+  self::throws(() → void => invalid-expression "pkg/front_end/testcases/nnbd/null_shorting.dart:88:43: Error: Property 'nullable1' cannot be accessed on 'Class1?' because it is potentially null.
+ - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting.dart'.
+Try accessing using ?. instead.
+  throws(() => (n1?.nonNullable1Method()).nullable1);
+                                          ^^^^^^^^^" in (let final self::Class1? #t18 = n1 in #t18 == null ?{self::Class1?} null : #t18{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}).{self::Class1::nullable1}{<nullable>}.{self::Class1?});
+  nullable1 = let final self::Class1? #t19 = n1 in #t19 == null ?{self::Class1?} null : #t19{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  nullable1 = let final self::Class1? #t20 = n1 in #t20 == null ?{self::Class1?} null : let final self::Class1? #t21 = #t20{self::Class1}.{self::Class1::nullable1}{self::Class1?} in #t21 == null ?{self::Class1?} null : #t21{self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  nullable1 = let final self::Class1? #t22 = n1 in #t22 == null ?{self::Class1?} null : let final self::Class1? #t23 = #t22{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1}{self::Class1?} in #t23 == null ?{self::Class1?} null : #t23{self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t24 = n1 in #t24 == null ?{self::Class1?} null : let final self::Class1? #t25 = #t24{self::Class1}.{self::Class1::nullable1}{self::Class1?} in #t25 == null ?{self::Class1?} null : #t25{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t26 = n1 in #t26 == null ?{self::Class1?} null : #t26{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1}{self::Class1?};
+  nullable1 = let final self::Class1? #t27 = n1 in #t27 == null ?{self::Class1?} null : #t27{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1}{self::Class1?};
+  let final self::Class1? #t28 = n1 in #t28 == null ?{self::Class1?} null : #t28{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1} = new self::Class1::•();
+  nullable1 = let final self::Class1? #t29 = n1 in #t29 == null ?{self::Class1?} null : #t29{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t30 = n1 in #t30 == null ?{self::Class1?} null : #t30{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1Method}(){() → self::Class1};
+  nullable1 = let final self::Class1? #t31 = n1 in #t31 == null ?{self::Class1?} null : #t31{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t32 = n1 in #t32 == null ?{self::Class1?} null : #t32{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1}{self::Class1?};
+  let final self::Class1? #t33 = n1 in #t33 == null ?{self::Class1?} null : #t33{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t34 = n1 in #t34 == null ?{self::Class1?} null : #t34{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t35 = n1 in #t35 == null ?{self::Class1?} null : #t35{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1}{self::Class1?};
+  let final self::Class1? #t36 = n1 in #t36 == null ?{self::Class1?} null : #t36{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  nullable1 = let final self::Class1? #t37 = n1 in #t37 == null ?{self::Class1?} null : #t37{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t38 = n1 in #t38 == null ?{self::Class1?} null : let final self::Class1? #t39 = #t38{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1}{self::Class1?} in #t39 == null ?{self::Class1?} null : #t39{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t40 = n1 in #t40 == null ?{self::Class1?} null : #t40{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1}{self::Class1?};
+  nullable1 = let final self::Class1? #t41 = n1 in #t41 == null ?{self::Class1?} null : #t41{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1}{self::Class1?};
+  let final self::Class1? #t42 = n1 in #t42 == null ?{self::Class1?} null : #t42{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  nullable1 = let final self::Class1? #t43 = n1 in #t43 == null ?{self::Class1?} null : #t43{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t44 = n1 in #t44 == null ?{self::Class1?} null : #t44{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+  nullable1 = let final self::Class1? #t45 = n1 in #t45 == null ?{self::Class1?} null : #t45{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t46 = n1 in #t46 == null ?{self::Class1?} null : #t46{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1}{self::Class1?};
+  let final self::Class1? #t47 = n1 in #t47 == null ?{self::Class1?} null : #t47{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t48 = n1 in #t48 == null ?{self::Class1?} null : #t48{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t49 = n1 in #t49 == null ?{self::Class1?} null : #t49{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1}{self::Class1?};
+  nullable1 = let final self::Class1? #t50 = n1 in #t50 == null ?{self::Class1?} null : #t50{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1}{self::Class1?};
+  let final self::Class1? #t51 = n1 in #t51 == null ?{self::Class1?} null : #t51{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1} = new self::Class1::•();
+  nullable1 = let final self::Class1? #t52 = n1 in #t52 == null ?{self::Class1?} null : #t52{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t53 = n1 in #t53 == null ?{self::Class1?} null : #t53{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1Method}(){() → self::Class1};
+  nullable1 = let final self::Class1? #t54 = n1 in #t54 == null ?{self::Class1?} null : #t54{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t55 = n1 in #t55 == null ?{self::Class1?} null : #t55{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1}{self::Class1?};
+  nullable1 = let final self::Class1? #t56 = n1 in #t56 == null ?{self::Class1?} null : #t56{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1}{self::Class1?};
+  let final self::Class1? #t57 = n1 in #t57 == null ?{self::Class1?} null : #t57{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1} = new self::Class1::•();
+  nullable1 = let final self::Class1? #t58 = n1 in #t58 == null ?{self::Class1?} null : #t58{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t59 = n1 in #t59 == null ?{self::Class1?} null : #t59{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1Method}(){() → self::Class1};
+  nullable1 = let final self::Class1? #t60 = n1 in #t60 == null ?{self::Class1?} null : #t60{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t61 = n1 in #t61 == null ?{self::Class1?} null : #t61{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1}{self::Class1?};
+  nullable1 = let final self::Class1? #t62 = n1 in #t62 == null ?{self::Class1?} null : #t62{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1}{self::Class1?};
+  let final self::Class1? #t63 = n1 in #t63 == null ?{self::Class1?} null : #t63{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1} = new self::Class1::•();
+  nullable1 = let final self::Class1? #t64 = n1 in #t64 == null ?{self::Class1?} null : #t64{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t65 = n1 in #t65 == null ?{self::Class1?} null : #t65{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1Method}(){() → self::Class1};
+  nullable1 = let final self::Class1? #t66 = n1 in #t66 == null ?{self::Class1?} null : #t66{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t67 = n1 in #t67 == null ?{self::Class1?} null : #t67{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1}{self::Class1?};
+  let final self::Class1? #t68 = n1 in #t68 == null ?{self::Class1?} null : #t68{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  nullable1 = let final self::Class1? #t69 = n1 in #t69 == null ?{self::Class1?} null : #t69{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t70 = n1 in #t70 == null ?{self::Class1?} null : #t70{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t71 = n1 in #t71 == null ?{self::Class1?} null : #t71{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1}{self::Class1?};
+  nullable1 = let final self::Class1? #t72 = n1 in #t72 == null ?{self::Class1?} null : #t72{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1}{self::Class1?};
+  let final self::Class1? #t73 = n1 in #t73 == null ?{self::Class1?} null : #t73{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  nullable1 = let final self::Class1? #t74 = n1 in #t74 == null ?{self::Class1?} null : #t74{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t75 = n1 in #t75 == null ?{self::Class1?} null : #t75{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+  nullable1 = let final self::Class1? #t76 = n1 in #t76 == null ?{self::Class1?} null : #t76{self::Class1}.{self::Class1::nullable1} = new self::Class1::•().{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t77 = n1 in #t77 == null ?{self::Class1?} null : #t77{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1}{self::Class1?};
+  let final self::Class1? #t78 = n1 in #t78 == null ?{self::Class1?} null : #t78{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nullable1} = new self::Class1::•();
+  let final self::Class1? #t79 = n1 in #t79 == null ?{self::Class1?} null : #t79{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t80 = n1 in #t80 == null ?{self::Class1?} null : let final self::Class1? #t81 = #t80{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1} in #t81 == null ?{self::Class1?} null : #t81{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+}
+static method indexAccess(self::Class1? n1, self::Class2? n2, self::Class3? n3) → void {
+  self::Class1? nullable1 = n1;
+  self::Class2? nullable2 = n2;
+  self::Class3? nullable3 = n3;
+  let final self::Class1? #t82 = n1 in #t82 == null ?{self::Class1?} null : #t82{self::Class1}.{self::Class1::[]}(nullable1){(self::Class1?) → self::Class1?};
+  let final self::Class1? #t83 = n1 in #t83 == null ?{self::Class1?} null : #t83{self::Class1}.{self::Class1::[]=}(nullable1, new self::Class1::•()){(self::Class1?, self::Class1?) → void};
+  let final self::Class1? #t84 = n1 in #t84 == null ?{self::Class1?} null : let final self::Class1? #t85 = #t84{self::Class1}.{self::Class1::[]}(nullable1){(self::Class1?) → self::Class1?} in #t85 == null ?{self::Class1?} null : #t85{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t86 = n1 in #t86 == null ?{self::Class1?} null : #t86{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::[]}(nullable1){(self::Class1?) → self::Class1?};
+  let final self::Class1? #t87 = n1 in #t87 == null ?{self::Class1?} null : #t87{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::[]=}(nullable1, new self::Class1::•()){(self::Class1?, self::Class1?) → void};
+  nullable1 = let final self::Class1? #t88 = n1 in #t88 == null ?{self::Class1?} null : let final self::Class1 #t89 = #t88{self::Class1}.{self::Class1::nonNullable1}{self::Class1} in let final self::Class1? #t90 = nullable1 in let final self::Class1 #t91 = new self::Class1::•() in let final void #t92 = #t89.{self::Class1::[]=}(#t90, #t91){(self::Class1?, self::Class1?) → void} in #t91;
+  let final self::Class1? #t93 = n1 in #t93 == null ?{self::Class1?} null : let final self::Class1? #t94 = #t93{self::Class1}.{self::Class1::nonNullable1}{self::Class1}.{self::Class1::[]}(nullable1){(self::Class1?) → self::Class1?} in #t94 == null ?{self::Class1?} null : #t94{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t95 = n1 in #t95 == null ?{self::Class2?} null : let final self::Class2 #t96 = #t95{self::Class1}.{self::Class1::nonNullable2}{self::Class2} in let final self::Class2? #t97 = nullable2 in #t96.{self::Class2::[]=}(#t97, #t96.{self::Class2::[]}(#t97){(self::Class2?) → self::Class2}.{self::Class2::+}(0){(core::int) → self::Class2}){(self::Class2?, self::Class2?) → void};
+  nullable2 = let final self::Class1? #t98 = n1 in #t98 == null ?{self::Class2?} null : let final self::Class2 #t99 = #t98{self::Class1}.{self::Class1::nonNullable2}{self::Class2} in let final self::Class2? #t100 = nullable2 in let final self::Class2 #t101 = #t99.{self::Class2::[]}(#t100){(self::Class2?) → self::Class2}.{self::Class2::+}(0){(core::int) → self::Class2} in let final void #t102 = #t99.{self::Class2::[]=}(#t100, #t101){(self::Class2?, self::Class2?) → void} in #t101;
+  let final self::Class1? #t103 = n1 in #t103 == null ?{self::Class1?} null : let final self::Class1? #t104 = nullable1 in #t103{self::Class1}.{self::Class1::[]}(#t104){(self::Class1?) → self::Class1?} == null ?{self::Class1?} #t103{self::Class1}.{self::Class1::[]=}(#t104, nullable1){(self::Class1?, self::Class1?) → void} : null;
+  nullable1 = let final self::Class1? #t105 = n1 in #t105 == null ?{self::Class1?} null : let final self::Class1? #t106 = nullable1 in let final self::Class1? #t107 = #t105{self::Class1}.{self::Class1::[]}(#t106){(self::Class1?) → self::Class1?} in #t107 == null ?{self::Class1?} let final self::Class1? #t108 = nullable1 in let final void #t109 = #t105{self::Class1}.{self::Class1::[]=}(#t106, #t108){(self::Class1?, self::Class1?) → void} in #t108 : #t107{self::Class1};
+  let final self::Class2? #t110 = n2 in #t110 == null ?{self::Class2?} null : let final self::Class2? #t111 = nullable2 in #t110{self::Class2}.{self::Class2::[]=}(#t111, #t110{self::Class2}.{self::Class2::[]}(#t111){(self::Class2?) → self::Class2}.{self::Class2::+}(0){(core::int) → self::Class2}){(self::Class2?, self::Class2?) → void};
+  nullable2 = let final self::Class2? #t112 = n2 in #t112 == null ?{self::Class2?} null : let final self::Class2? #t113 = nullable2 in let final self::Class2 #t114 = #t112{self::Class2}.{self::Class2::[]}(#t113){(self::Class2?) → self::Class2}.{self::Class2::+}(0){(core::int) → self::Class2} in let final void #t115 = #t112{self::Class2}.{self::Class2::[]=}(#t113, #t114){(self::Class2?, self::Class2?) → void} in #t114;
+  let final self::Class2? #t116 = n2 in #t116 == null ?{self::Class2?} null : let final self::Class2? #t117 = nullable2 in #t116{self::Class2}.{self::Class2::[]=}(#t117, #t116{self::Class2}.{self::Class2::[]}(#t117){(self::Class2?) → self::Class2}.{self::Class2::+}(0){(core::int) → self::Class2}){(self::Class2?, self::Class2?) → void};
+  nullable2 = let final self::Class2? #t118 = n2 in #t118 == null ?{self::Class2?} null : let final self::Class2? #t119 = nullable2 in let final self::Class2 #t120 = #t118{self::Class2}.{self::Class2::[]}(#t119){(self::Class2?) → self::Class2}.{self::Class2::+}(0){(core::int) → self::Class2} in let final void #t121 = #t118{self::Class2}.{self::Class2::[]=}(#t119, #t120){(self::Class2?, self::Class2?) → void} in #t120;
+  let final self::Class2? #t122 = n2 in #t122 == null ?{self::Class2?} null : let final self::Class2? #t123 = nullable2 in #t122{self::Class2}.{self::Class2::[]=}(#t123, #t122{self::Class2}.{self::Class2::[]}(#t123){(self::Class2?) → self::Class2}.{self::Class2::+}(1){(core::int) → self::Class2}){(self::Class2?, self::Class2?) → void};
+  nullable2 = let final self::Class2? #t124 = n2 in #t124 == null ?{self::Class2?} null : let final self::Class2? #t125 = nullable2 in let final self::Class2 #t126 = #t124{self::Class2}.{self::Class2::[]}(#t125){(self::Class2?) → self::Class2} in let final void #t127 = #t124{self::Class2}.{self::Class2::[]=}(#t125, #t126.{self::Class2::+}(1){(core::int) → self::Class2}){(self::Class2?, self::Class2?) → void} in #t126;
+  let final self::Class2? #t128 = n2 in #t128 == null ?{self::Class2?} null : let final self::Class2? #t129 = nullable2 in let final self::Class2 #t130 = #t128{self::Class2}.{self::Class2::[]}(#t129){(self::Class2?) → self::Class2}.{self::Class2::+}(1){(core::int) → self::Class2} in let final void #t131 = #t128{self::Class2}.{self::Class2::[]=}(#t129, #t130){(self::Class2?, self::Class2?) → void} in #t130;
+  nullable2 = let final self::Class2? #t132 = n2 in #t132 == null ?{self::Class2?} null : let final self::Class2? #t133 = nullable2 in let final self::Class2 #t134 = #t132{self::Class2}.{self::Class2::[]}(#t133){(self::Class2?) → self::Class2}.{self::Class2::+}(1){(core::int) → self::Class2} in let final void #t135 = #t132{self::Class2}.{self::Class2::[]=}(#t133, #t134){(self::Class2?, self::Class2?) → void} in #t134;
+  let final self::Class1? #t136 = n1 in #t136 == null ?{self::Class2?} null : let final self::Class2 #t137 = #t136{self::Class1}.{self::Class1::nonNullable2}{self::Class2} in let final self::Class2? #t138 = nullable2 in #t137.{self::Class2::[]=}(#t138, #t137.{self::Class2::[]}(#t138){(self::Class2?) → self::Class2}.{self::Class2::+}(1){(core::int) → self::Class2}){(self::Class2?, self::Class2?) → void};
+  nullable2 = let final self::Class1? #t139 = n1 in #t139 == null ?{self::Class2?} null : let final self::Class2 #t140 = #t139{self::Class1}.{self::Class1::nonNullable2}{self::Class2} in let final self::Class2? #t141 = nullable2 in let final self::Class2 #t142 = #t140.{self::Class2::[]}(#t141){(self::Class2?) → self::Class2} in let final void #t143 = #t140.{self::Class2::[]=}(#t141, #t142.{self::Class2::+}(1){(core::int) → self::Class2}){(self::Class2?, self::Class2?) → void} in #t142;
+  let final self::Class1? #t144 = n1 in #t144 == null ?{self::Class2?} null : let final self::Class2 #t145 = #t144{self::Class1}.{self::Class1::nonNullable2}{self::Class2} in let final self::Class2? #t146 = nullable2 in let final self::Class2 #t147 = #t145.{self::Class2::[]}(#t146){(self::Class2?) → self::Class2}.{self::Class2::+}(1){(core::int) → self::Class2} in let final void #t148 = #t145.{self::Class2::[]=}(#t146, #t147){(self::Class2?, self::Class2?) → void} in #t147;
+  nullable2 = let final self::Class1? #t149 = n1 in #t149 == null ?{self::Class2?} null : let final self::Class2 #t150 = #t149{self::Class1}.{self::Class1::nonNullable2}{self::Class2} in let final self::Class2? #t151 = nullable2 in let final self::Class2 #t152 = #t150.{self::Class2::[]}(#t151){(self::Class2?) → self::Class2}.{self::Class2::+}(1){(core::int) → self::Class2} in let final void #t153 = #t150.{self::Class2::[]=}(#t151, #t152){(self::Class2?, self::Class2?) → void} in #t152;
+  let final self::Class1? #t154 = n1 in #t154 == null ?{self::Class2?} null : #t154{self::Class1}.{self::Class1::nonNullable2}{self::Class2}.{self::Class2::[]}(nullable2){(self::Class2?) → self::Class2}.{self::Class2::[]}(nullable2){(self::Class2?) → self::Class2};
+  let final self::Class1? #t155 = n1 in #t155 == null ?{self::Class2?} null : #t155{self::Class1}.{self::Class1::nonNullable2}{self::Class2}.{self::Class2::[]}(nullable2){(self::Class2?) → self::Class2}.{self::Class2::[]=}(nullable2, new self::Class2::•()){(self::Class2?, self::Class2?) → void};
+  nullable2 = let final self::Class1? #t156 = n1 in #t156 == null ?{self::Class2?} null : let final self::Class2 #t157 = #t156{self::Class1}.{self::Class1::nonNullable2}{self::Class2}.{self::Class2::[]}(nullable2){(self::Class2?) → self::Class2} in let final self::Class2? #t158 = nullable2 in let final self::Class2 #t159 = new self::Class2::•() in let final void #t160 = #t157.{self::Class2::[]=}(#t158, #t159){(self::Class2?, self::Class2?) → void} in #t159;
+  let final self::Class1? #t161 = n1 in #t161 == null ?{self::Class2?} null : let final self::Class2? #t162 = #t161{self::Class1}.{self::Class1::nonNullable2}{self::Class2}.{self::Class2::[]}(nullable2){(self::Class2?) → self::Class2}.{self::Class2::[]}(nullable2){(self::Class2?) → self::Class2} in #t162 == null ?{self::Class2?} null : #t162{self::Class2}.{self::Class2::nonNullable2Method}(){() → self::Class2};
+  let final self::Class1? #t163 = n1 in #t163 == null ?{self::Class2?} null : let final self::Class2 #t164 = #t163{self::Class1}.{self::Class1::nonNullable2}{self::Class2}.{self::Class2::[]}(nullable2){(self::Class2?) → self::Class2} in let final self::Class2? #t165 = nullable2 in #t164.{self::Class2::[]=}(#t165, #t164.{self::Class2::[]}(#t165){(self::Class2?) → self::Class2}.{self::Class2::+}(0){(core::int) → self::Class2}){(self::Class2?, self::Class2?) → void};
+  nullable2 = let final self::Class1? #t166 = n1 in #t166 == null ?{self::Class2?} null : let final self::Class2 #t167 = #t166{self::Class1}.{self::Class1::nonNullable2}{self::Class2}.{self::Class2::[]}(nullable2){(self::Class2?) → self::Class2} in let final self::Class2? #t168 = nullable2 in let final self::Class2 #t169 = #t167.{self::Class2::[]}(#t168){(self::Class2?) → self::Class2}.{self::Class2::+}(0){(core::int) → self::Class2} in let final void #t170 = #t167.{self::Class2::[]=}(#t168, #t169){(self::Class2?, self::Class2?) → void} in #t169;
+  let final self::Class1? #t171 = n1 in #t171 == null ?{self::Class2?} null : let final self::Class2 #t172 = #t171{self::Class1}.{self::Class1::nonNullable2}{self::Class2}.{self::Class2::[]}(nullable2){(self::Class2?) → self::Class2} in let final self::Class2? #t173 = nullable2 in #t172.{self::Class2::[]=}(#t173, #t172.{self::Class2::[]}(#t173){(self::Class2?) → self::Class2}.{self::Class2::+}(1){(core::int) → self::Class2}){(self::Class2?, self::Class2?) → void};
+  nullable2 = let final self::Class1? #t174 = n1 in #t174 == null ?{self::Class2?} null : let final self::Class2 #t175 = #t174{self::Class1}.{self::Class1::nonNullable2}{self::Class2}.{self::Class2::[]}(nullable2){(self::Class2?) → self::Class2} in let final self::Class2? #t176 = nullable2 in let final self::Class2 #t177 = #t175.{self::Class2::[]}(#t176){(self::Class2?) → self::Class2} in let final void #t178 = #t175.{self::Class2::[]=}(#t176, #t177.{self::Class2::+}(1){(core::int) → self::Class2}){(self::Class2?, self::Class2?) → void} in #t177;
+  let final self::Class1? #t179 = n1 in #t179 == null ?{self::Class2?} null : let final self::Class2 #t180 = #t179{self::Class1}.{self::Class1::nonNullable2}{self::Class2}.{self::Class2::[]}(nullable2){(self::Class2?) → self::Class2} in let final self::Class2? #t181 = nullable2 in let final self::Class2 #t182 = #t180.{self::Class2::[]}(#t181){(self::Class2?) → self::Class2}.{self::Class2::+}(1){(core::int) → self::Class2} in let final void #t183 = #t180.{self::Class2::[]=}(#t181, #t182){(self::Class2?, self::Class2?) → void} in #t182;
+  nullable2 = let final self::Class1? #t184 = n1 in #t184 == null ?{self::Class2?} null : let final self::Class2 #t185 = #t184{self::Class1}.{self::Class1::nonNullable2}{self::Class2}.{self::Class2::[]}(nullable2){(self::Class2?) → self::Class2} in let final self::Class2? #t186 = nullable2 in let final self::Class2 #t187 = #t185.{self::Class2::[]}(#t186){(self::Class2?) → self::Class2}.{self::Class2::+}(1){(core::int) → self::Class2} in let final void #t188 = #t185.{self::Class2::[]=}(#t186, #t187){(self::Class2?, self::Class2?) → void} in #t187;
+  let final self::Class1? #t189 = n1 in #t189 == null ?{self::Class1?} null : let final self::Class1? #t190 = #t189{self::Class1}.{self::Class1::[]}(nullable1){(self::Class1?) → self::Class1?} in #t190 == null ?{self::Class1?} null : #t190{self::Class1}.{self::Class1::[]}(nullable1){(self::Class1?) → self::Class1?};
+  let final self::Class1? #t191 = n1 in #t191 == null ?{self::Class1?} null : let final self::Class1? #t192 = #t191{self::Class1}.{self::Class1::[]}(nullable1){(self::Class1?) → self::Class1?} in #t192 == null ?{self::Class1?} null : #t192{self::Class1}.{self::Class1::[]=}(nullable1, new self::Class1::•()){(self::Class1?, self::Class1?) → void};
+  nullable1 = let final self::Class1? #t193 = n1 in #t193 == null ?{self::Class1?} null : let final self::Class1? #t194 = #t193{self::Class1}.{self::Class1::[]}(nullable1){(self::Class1?) → self::Class1?} in #t194 == null ?{self::Class1?} null : let final self::Class1? #t195 = nullable1 in let final self::Class1 #t196 = new self::Class1::•() in let final void #t197 = #t194{self::Class1}.{self::Class1::[]=}(#t195, #t196){(self::Class1?, self::Class1?) → void} in #t196;
+  let final self::Class1? #t198 = n1 in #t198 == null ?{self::Class1?} null : let final self::Class1? #t199 = #t198{self::Class1}.{self::Class1::[]}(nullable1){(self::Class1?) → self::Class1?} in #t199 == null ?{self::Class1?} null : let final self::Class1? #t200 = #t199{self::Class1}.{self::Class1::[]}(nullable1){(self::Class1?) → self::Class1?} in #t200 == null ?{self::Class1?} null : #t200{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+  nullable1 = let final self::Class1? #t201 = n1 in #t201 == null ?{self::Class1?} null : let final self::Class1? #t202 = #t201{self::Class1}.{self::Class1::[]}(nullable1){(self::Class1?) → self::Class1?} in #t202 == null ?{self::Class1?} null : let final self::Class1? #t203 = #t202{self::Class1}.{self::Class1::[]}(nullable1){(self::Class1?) → self::Class1?} in #t203 == null ?{self::Class1?} null : #t203{self::Class1}.{self::Class1::nonNullable1Method}(){() → self::Class1};
+  let final self::Class1? #t204 = n1 in #t204 == null ?{self::Class1?} null : let final self::Class1? #t205 = #t204{self::Class1}.{self::Class1::[]}(nullable1){(self::Class1?) → self::Class1?} in #t205 == null ?{self::Class1?} null : let final self::Class1? #t206 = nullable1 in #t205{self::Class1}.{self::Class1::[]}(#t206){(self::Class1?) → self::Class1?} == null ?{self::Class1?} #t205{self::Class1}.{self::Class1::[]=}(#t206, nullable1){(self::Class1?, self::Class1?) → void} : null;
+  nullable1 = let final self::Class1? #t207 = n1 in #t207 == null ?{self::Class1?} null : let final self::Class1? #t208 = #t207{self::Class1}.{self::Class1::[]}(nullable1){(self::Class1?) → self::Class1?} in #t208 == null ?{self::Class1?} null : let final self::Class1? #t209 = nullable1 in let final self::Class1? #t210 = #t208{self::Class1}.{self::Class1::[]}(#t209){(self::Class1?) → self::Class1?} in #t210 == null ?{self::Class1?} let final self::Class1? #t211 = nullable1 in let final void #t212 = #t208{self::Class1}.{self::Class1::[]=}(#t209, #t211){(self::Class1?, self::Class1?) → void} in #t211 : #t210{self::Class1};
+  let final self::Class3? #t213 = n3 in #t213 == null ?{self::Class2?} null : let final self::Class2? #t214 = #t213{self::Class3}.{self::Class3::[]}(nullable3){(self::Class3?) → self::Class2?} in #t214 == null ?{self::Class2?} null : let final self::Class2? #t215 = nullable2 in #t214{self::Class2}.{self::Class2::[]=}(#t215, #t214{self::Class2}.{self::Class2::[]}(#t215){(self::Class2?) → self::Class2}.{self::Class2::+}(0){(core::int) → self::Class2}){(self::Class2?, self::Class2?) → void};
+  nullable2 = let final self::Class3? #t216 = n3 in #t216 == null ?{self::Class2?} null : let final self::Class2? #t217 = #t216{self::Class3}.{self::Class3::[]}(nullable3){(self::Class3?) → self::Class2?} in #t217 == null ?{self::Class2?} null : let final self::Class2? #t218 = nullable2 in let final self::Class2 #t219 = #t217{self::Class2}.{self::Class2::[]}(#t218){(self::Class2?) → self::Class2}.{self::Class2::+}(0){(core::int) → self::Class2} in let final void #t220 = #t217{self::Class2}.{self::Class2::[]=}(#t218, #t219){(self::Class2?, self::Class2?) → void} in #t219;
+  let final self::Class3? #t221 = n3 in #t221 == null ?{self::Class2?} null : let final self::Class2? #t222 = #t221{self::Class3}.{self::Class3::[]}(nullable3){(self::Class3?) → self::Class2?} in #t222 == null ?{self::Class2?} null : let final self::Class2? #t223 = nullable2 in #t222{self::Class2}.{self::Class2::[]=}(#t223, #t222{self::Class2}.{self::Class2::[]}(#t223){(self::Class2?) → self::Class2}.{self::Class2::+}(1){(core::int) → self::Class2}){(self::Class2?, self::Class2?) → void};
+  nullable2 = let final self::Class3? #t224 = n3 in #t224 == null ?{self::Class2?} null : let final self::Class2? #t225 = #t224{self::Class3}.{self::Class3::[]}(nullable3){(self::Class3?) → self::Class2?} in #t225 == null ?{self::Class2?} null : let final self::Class2? #t226 = nullable2 in let final self::Class2 #t227 = #t225{self::Class2}.{self::Class2::[]}(#t226){(self::Class2?) → self::Class2} in let final void #t228 = #t225{self::Class2}.{self::Class2::[]=}(#t226, #t227.{self::Class2::+}(1){(core::int) → self::Class2}){(self::Class2?, self::Class2?) → void} in #t227;
+  let final self::Class3? #t229 = n3 in #t229 == null ?{self::Class2?} null : let final self::Class2? #t230 = #t229{self::Class3}.{self::Class3::[]}(nullable3){(self::Class3?) → self::Class2?} in #t230 == null ?{self::Class2?} null : let final self::Class2? #t231 = nullable2 in let final self::Class2 #t232 = #t230{self::Class2}.{self::Class2::[]}(#t231){(self::Class2?) → self::Class2}.{self::Class2::+}(1){(core::int) → self::Class2} in let final void #t233 = #t230{self::Class2}.{self::Class2::[]=}(#t231, #t232){(self::Class2?, self::Class2?) → void} in #t232;
+  nullable2 = let final self::Class3? #t234 = n3 in #t234 == null ?{self::Class2?} null : let final self::Class2? #t235 = #t234{self::Class3}.{self::Class3::[]}(nullable3){(self::Class3?) → self::Class2?} in #t235 == null ?{self::Class2?} null : let final self::Class2? #t236 = nullable2 in let final self::Class2 #t237 = #t235{self::Class2}.{self::Class2::[]}(#t236){(self::Class2?) → self::Class2}.{self::Class2::+}(1){(core::int) → self::Class2} in let final void #t238 = #t235{self::Class2}.{self::Class2::[]=}(#t236, #t237){(self::Class2?, self::Class2?) → void} in #t237;
+}
+static method operatorAccess(self::Class1? n1, self::Class2? n2) → void {
+  self::Class2? nullable2 = n2;
+  self::throws(() → void => invalid-expression "pkg/front_end/testcases/nnbd/null_shorting.dart:220:33: Error: Operator '+' cannot be called on 'Class1?' because it is potentially null.
+ - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting.dart'.
+  throws(() => n1?.nonNullable1 + 0);
+                                ^" in (let final self::Class1? #t239 = n1 in #t239 == null ?{self::Class1?} null : #t239{self::Class1}.{self::Class1::nonNullable1}{self::Class1}).{self::Class1::+}(0){(core::int) → self::Class1?});
+  self::throws(() → void => invalid-expression "pkg/front_end/testcases/nnbd/null_shorting.dart:221:16: Error: Operator 'unary-' cannot be called on 'Class1?' because it is potentially null.
+ - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting.dart'.
+  throws(() => -n1?.nonNullable1);
+               ^" in (let final self::Class1? #t240 = n1 in #t240 == null ?{self::Class1?} null : #t240{self::Class1}.{self::Class1::nonNullable1}{self::Class1}).{self::Class1::unary-}(){() → self::Class1?});
+  let final self::Class2? #t241 = n2 in #t241 == null ?{self::Class2?} null : #t241.{self::Class2::nonNullable2} = #t241.{self::Class2::nonNullable2}{self::Class2}.{self::Class2::+}(0){(core::int) → self::Class2};
+  nullable2 = let final self::Class2? #t242 = n2 in #t242 == null ?{self::Class2?} null : let final self::Class2 #t243 = #t242.{self::Class2::nonNullable2}{self::Class2}.{self::Class2::+}(0){(core::int) → self::Class2} in let final void #t244 = #t242.{self::Class2::nonNullable2} = #t243 in #t243;
+  let final self::Class2? #t245 = n2 in #t245 == null ?{self::Class2?} null : let final self::Class2 #t246 = #t245{self::Class2}.{self::Class2::nonNullable2}{self::Class2} in #t246.{self::Class2::nonNullable2} = #t246.{self::Class2::nonNullable2}{self::Class2}.{self::Class2::+}(0){(core::int) → self::Class2};
+  nullable2 = let final self::Class2? #t247 = n2 in #t247 == null ?{self::Class2?} null : let final self::Class2 #t248 = #t247{self::Class2}.{self::Class2::nonNullable2}{self::Class2} in #t248.{self::Class2::nonNullable2} = #t248.{self::Class2::nonNullable2}{self::Class2}.{self::Class2::+}(0){(core::int) → self::Class2};
+  let final self::Class2? #t249 = n2 in #t249 == null ?{self::Class2?} null : #t249.{self::Class2::nonNullable2} = #t249.{self::Class2::nonNullable2}{self::Class2}.{self::Class2::+}(1){(core::int) → self::Class2};
+  nullable2 = let final self::Class2? #t250 = n2 in #t250 == null ?{self::Class2?} null : let final self::Class2 #t251 = #t250.{self::Class2::nonNullable2}{self::Class2} in let final void #t252 = #t250.{self::Class2::nonNullable2} = #t251.{self::Class2::+}(1){(core::int) → self::Class2} in #t251;
+  let final self::Class2? #t253 = n2 in #t253 == null ?{self::Class2?} null : let final self::Class2 #t254 = #t253.{self::Class2::nonNullable2}{self::Class2}.{self::Class2::+}(1){(core::int) → self::Class2} in let final void #t255 = #t253.{self::Class2::nonNullable2} = #t254 in #t254;
+  nullable2 = let final self::Class2? #t256 = n2 in #t256 == null ?{self::Class2?} null : let final self::Class2 #t257 = #t256.{self::Class2::nonNullable2}{self::Class2}.{self::Class2::+}(1){(core::int) → self::Class2} in let final void #t258 = #t256.{self::Class2::nonNullable2} = #t257 in #t257;
+}
+static method ifNull(self::Class1? n1) → void {
+  self::Class1? nullable1 = n1;
+  let final self::Class1? #t259 = n1 in #t259 == null ?{self::Class1?} null : #t259.{self::Class1::nullable1}{self::Class1?} == null ?{self::Class1} #t259.{self::Class1::nullable1} = n1{self::Class1} : null;
+  n1 = let final self::Class1? #t260 = n1 in #t260 == null ?{self::Class1?} null : let final self::Class1? #t261 = #t260.{self::Class1::nullable1}{self::Class1?} in #t261 == null ?{self::Class1} #t260.{self::Class1::nullable1} = n1{self::Class1} : #t261{self::Class1};
+  let final self::Class1? #t262 = n1 in #t262 == null ?{self::Class1?} null : let final self::Class1 #t263 = #t262{self::Class1}.{self::Class1::nonNullable1}{self::Class1} in #t263.{self::Class1::nullable1}{self::Class1?} == null ?{self::Class1} #t263.{self::Class1::nullable1} = n1{self::Class1} : null;
+  n1 = let final self::Class1? #t264 = n1 in #t264 == null ?{self::Class1?} null : let final self::Class1 #t265 = #t264{self::Class1}.{self::Class1::nonNullable1}{self::Class1} in let final self::Class1? #t266 = #t265.{self::Class1::nullable1}{self::Class1?} in #t266 == null ?{self::Class1} #t265.{self::Class1::nullable1} = n1{self::Class1} : #t266{self::Class1};
+  let final self::Class1? #t267 = n1 in #t267 == null ?{self::Class1?} null : let final self::Class1 #t268 = #t267{self::Class1}.{self::Class1::nonNullable1}{self::Class1} in let final self::Class1 #t269 = n1{self::Class1} in #t268.{self::Class1::[]}(#t269){(self::Class1?) → self::Class1?} == null ?{self::Class1} #t268.{self::Class1::[]=}(#t269, n1{self::Class1}){(self::Class1?, self::Class1?) → void} : null;
+  n1 = let final self::Class1? #t270 = n1 in #t270 == null ?{self::Class1?} null : let final self::Class1 #t271 = #t270{self::Class1}.{self::Class1::nonNullable1}{self::Class1} in let final self::Class1 #t272 = n1{self::Class1} in let final self::Class1? #t273 = #t271.{self::Class1::[]}(#t272){(self::Class1?) → self::Class1?} in #t273 == null ?{self::Class1} let final self::Class1 #t274 = n1{self::Class1} in let final void #t275 = #t271.{self::Class1::[]=}(#t272, #t274){(self::Class1?, self::Class1?) → void} in #t274 : #t273{self::Class1};
+}
+static method throws(() → void f) → void {
+  try {
+    f(){() → void};
+  }
+  on core::Object catch(final core::Object _) {
+    return;
+  }
+  throw "Expected exception.";
+}
diff --git a/pkg/front_end/testcases/nnbd/null_shorting_cascade.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/null_shorting_cascade.dart.weak.modular.expect
new file mode 100644
index 0000000..740e044
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/null_shorting_cascade.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  method method() → self::Class
+    return this;
+}
+extension Extension on self::Class {
+  method extensionMethod = self::Extension|extensionMethod;
+  tearoff extensionMethod = self::Extension|get#extensionMethod;
+}
+static method Extension|extensionMethod(lowered final self::Class #this) → self::Class
+  return #this;
+static method Extension|get#extensionMethod(lowered final self::Class #this) → () → self::Class
+  return () → self::Class => self::Extension|extensionMethod(#this);
+static method main() → dynamic {
+  self::Class? c;
+  let final self::Class? #t1 = c in #t1 == null ?{self::Class?} null : block {
+    #t1{self::Class}.{self::Class::method}(){() → self::Class};
+  } =>#t1;
+  let final self::Class? #t2 = c in #t2 == null ?{self::Class?} null : block {
+    #t2{self::Class}.{self::Class::method}(){() → self::Class};
+    #t2{self::Class}.{self::Class::method}(){() → self::Class};
+  } =>#t2;
+  let final self::Class? #t3 = c in #t3 == null ?{self::Class?} null : block {
+    self::Extension|extensionMethod(#t3{self::Class});
+  } =>#t3;
+  let final self::Class? #t4 = c in #t4 == null ?{self::Class?} null : block {
+    self::Extension|extensionMethod(#t4{self::Class});
+    self::Extension|extensionMethod(#t4{self::Class});
+  } =>#t4;
+}
diff --git a/pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart.weak.modular.expect
new file mode 100644
index 0000000..410df6c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart.weak.modular.expect
@@ -0,0 +1,298 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart:93:59: Error: Property 'nullable1' cannot be accessed on 'Class1?' because it is potentially null.
+//  - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart'.
+// Try accessing using ?. instead.
+//   throws(() => (Extension1(n1)?.nullable1 = new Class1()).nullable1);
+//                                                           ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart:94:55: Error: Property 'nullable1' cannot be accessed on 'Class1?' because it is potentially null.
+//  - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart'.
+// Try accessing using ?. instead.
+//   throws(() => (Extension1(n1)?.nonNullable1Method()).nullable1);
+//                                                       ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart:244:45: Error: Operator '+' cannot be called on 'Class1?' because it is potentially null.
+//  - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart'.
+//   throws(() => Extension1(n1)?.nonNullable1 + 0);
+//                                             ^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart:245:16: Error: Operator 'unary-' cannot be called on 'Class1?' because it is potentially null.
+//  - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart'.
+//   throws(() => -Extension1(n1)?.nonNullable1);
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+  get property() → self::Class1?
+    return null;
+  set property(self::Class1? value) → void {}
+  get property1() → self::Class1
+    return new self::Class1::•();
+  get property2() → self::Class2
+    return new self::Class2::•();
+}
+class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2
+    : super core::Object::•()
+    ;
+  get property() → self::Class2
+    return this;
+  set property(self::Class2 value) → void {}
+}
+class Class3 extends core::Object {
+  synthetic constructor •() → self::Class3
+    : super core::Object::•()
+    ;
+  get property() → self::Class2?
+    return null;
+}
+extension Extension1 on self::Class1 {
+  get nullable1 = self::Extension1|get#nullable1;
+  method nonNullable1Method = self::Extension1|nonNullable1Method;
+  tearoff nonNullable1Method = self::Extension1|get#nonNullable1Method;
+  operator [] = self::Extension1|[];
+  operator []= = self::Extension1|[]=;
+  operator + = self::Extension1|+;
+  operator unary- = self::Extension1|unary-;
+  get nonNullable1 = self::Extension1|get#nonNullable1;
+  get nonNullable2 = self::Extension1|get#nonNullable2;
+  set nullable1 = self::Extension1|set#nullable1;
+}
+extension Extension2 on self::Class2 {
+  method nonNullable2Method = self::Extension2|nonNullable2Method;
+  tearoff nonNullable2Method = self::Extension2|get#nonNullable2Method;
+  operator [] = self::Extension2|[];
+  operator []= = self::Extension2|[]=;
+  operator + = self::Extension2|+;
+  operator unary- = self::Extension2|unary-;
+  get nonNullable2 = self::Extension2|get#nonNullable2;
+  set nonNullable2 = self::Extension2|set#nonNullable2;
+}
+extension Extension3 on self::Class3 {
+  operator [] = self::Extension3|[];
+}
+static method Extension1|get#nullable1(lowered final self::Class1 #this) → self::Class1?
+  return #this.{self::Class1::property1}{self::Class1};
+static method Extension1|set#nullable1(lowered final self::Class1 #this, self::Class1? value) → void {
+  #this.{self::Class1::property} = value;
+}
+static method Extension1|nonNullable1Method(lowered final self::Class1 #this) → self::Class1
+  return self::Extension1|get#nonNullable1(#this);
+static method Extension1|get#nonNullable1Method(lowered final self::Class1 #this) → () → self::Class1
+  return () → self::Class1 => self::Extension1|nonNullable1Method(#this);
+static method Extension1|[](lowered final self::Class1 #this, self::Class1? key) → self::Class1?
+  return self::Extension1|get#nullable1(#this);
+static method Extension1|[]=(lowered final self::Class1 #this, self::Class1? key, self::Class1? value) → void {
+  #this.{self::Class1::property} = value;
+}
+static method Extension1|+(lowered final self::Class1 #this, core::int value) → self::Class1?
+  return self::Extension1|get#nullable1(#this);
+static method Extension1|unary-(lowered final self::Class1 #this) → self::Class1?
+  return self::Extension1|get#nullable1(#this);
+static method Extension1|get#nonNullable1(lowered final self::Class1 #this) → self::Class1
+  return #this.{self::Class1::property1}{self::Class1};
+static method Extension1|get#nonNullable2(lowered final self::Class1 #this) → self::Class2
+  return #this.{self::Class1::property2}{self::Class2};
+static method Extension2|nonNullable2Method(lowered final self::Class2 #this) → self::Class2
+  return self::Extension2|get#nonNullable2(#this);
+static method Extension2|get#nonNullable2Method(lowered final self::Class2 #this) → () → self::Class2
+  return () → self::Class2 => self::Extension2|nonNullable2Method(#this);
+static method Extension2|[](lowered final self::Class2 #this, self::Class2? key) → self::Class2
+  return #this.{self::Class2::property}{self::Class2};
+static method Extension2|[]=(lowered final self::Class2 #this, self::Class2? key, self::Class2? value) → void
+  return #this.{self::Class2::property}{self::Class2};
+static method Extension2|+(lowered final self::Class2 #this, core::int value) → self::Class2
+  return #this.{self::Class2::property}{self::Class2};
+static method Extension2|unary-(lowered final self::Class2 #this) → self::Class2
+  return #this.{self::Class2::property}{self::Class2};
+static method Extension2|get#nonNullable2(lowered final self::Class2 #this) → self::Class2
+  return #this.{self::Class2::property}{self::Class2};
+static method Extension2|set#nonNullable2(lowered final self::Class2 #this, self::Class2 value) → void {
+  #this.{self::Class2::property} = value;
+}
+static method Extension3|[](lowered final self::Class3 #this, self::Class3? key) → self::Class2?
+  return #this.{self::Class3::property}{self::Class2?};
+static method main() → dynamic {
+  self::propertyAccess(null);
+  self::indexAccess(null, null, null);
+  self::operatorAccess(null, null);
+  self::ifNull(null);
+}
+static method propertyAccess(self::Class1? n1) → void {
+  self::Class1? nullable1 = n1;
+  let final self::Class1? #t1 = n1 in #t1 == null ?{self::Class1?} null : self::Extension1|get#nullable1(#t1{self::Class1});
+  let final self::Class1? #t2 = n1 in #t2 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t2{self::Class1}, new self::Class1::•());
+  nullable1 = let final self::Class1? #t3 = n1 in #t3 == null ?{self::Class1?} null : let final self::Class1 #t4 = new self::Class1::•() in let final void #t5 = self::Extension1|set#nullable1(#t3{self::Class1}, #t4) in #t4;
+  let final self::Class1? #t6 = n1 in #t6 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t6{self::Class1});
+  let final self::Class1? #t7 = n1 in #t7 == null ?{self::Class1?} null : self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(#t7{self::Class1}));
+  let final self::Class1? #t8 = n1 in #t8 == null ?{self::Class1?} null : let final self::Class1? #t9 = self::Extension1|get#nullable1(#t8{self::Class1}) in #t9 == null ?{self::Class1?} null : self::Extension1|get#nullable1(#t9{self::Class1});
+  let final self::Class1? #t10 = n1 in #t10 == null ?{self::Class1?} null : let final self::Class1? #t11 = self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(#t10{self::Class1})) in #t11 == null ?{self::Class1?} null : self::Extension1|get#nullable1(#t11{self::Class1});
+  let final self::Class1? #t12 = n1 in #t12 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t12{self::Class1}), new self::Class1::•());
+  let final self::Class1? #t13 = n1 in #t13 == null ?{self::Class1?} null : let final self::Class1? #t14 = self::Extension1|get#nullable1(#t13{self::Class1}) in #t14 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t14{self::Class1}, new self::Class1::•());
+  let final self::Class1? #t15 = n1 in #t15 == null ?{self::Class1?} null : let final self::Class1? #t16 = self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(#t15{self::Class1})) in #t16 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t16{self::Class1}, new self::Class1::•());
+  let final self::Class1? #t17 = let final self::Class1? #t18 = n1 in #t18 == null ?{self::Class1?} null : self::Extension1|get#nullable1(#t18{self::Class1}) in #t17 == null ?{self::Class1?} null : self::Extension1|get#nullable1(#t17{self::Class1});
+  self::throws(() → void => invalid-expression "pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart:93:59: Error: Property 'nullable1' cannot be accessed on 'Class1?' because it is potentially null.
+ - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart'.
+Try accessing using ?. instead.
+  throws(() => (Extension1(n1)?.nullable1 = new Class1()).nullable1);
+                                                          ^^^^^^^^^" in self::Extension1|get#nullable1(let final self::Class1? #t19 = n1 in #t19 == null ?{self::Class1?} null : let final self::Class1 #t20 = new self::Class1::•() in let final void #t21 = self::Extension1|set#nullable1(#t19{self::Class1}, #t20) in #t20));
+  self::throws(() → void => invalid-expression "pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart:94:55: Error: Property 'nullable1' cannot be accessed on 'Class1?' because it is potentially null.
+ - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart'.
+Try accessing using ?. instead.
+  throws(() => (Extension1(n1)?.nonNullable1Method()).nullable1);
+                                                      ^^^^^^^^^" in self::Extension1|get#nullable1(let final self::Class1? #t22 = n1 in #t22 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t22{self::Class1})));
+  nullable1 = let final self::Class1? #t23 = n1 in #t23 == null ?{self::Class1?} null : let final self::Class1 #t24 = new self::Class1::•() in let final void #t25 = self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t23{self::Class1}), #t24) in #t24;
+  nullable1 = let final self::Class1? #t26 = n1 in #t26 == null ?{self::Class1?} null : let final self::Class1? #t27 = self::Extension1|get#nullable1(#t26{self::Class1}) in #t27 == null ?{self::Class1?} null : let final self::Class1 #t28 = new self::Class1::•() in let final void #t29 = self::Extension1|set#nullable1(#t27{self::Class1}, #t28) in #t28;
+  nullable1 = let final self::Class1? #t30 = n1 in #t30 == null ?{self::Class1?} null : let final self::Class1? #t31 = self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(#t30{self::Class1})) in #t31 == null ?{self::Class1?} null : let final self::Class1 #t32 = new self::Class1::•() in let final void #t33 = self::Extension1|set#nullable1(#t31{self::Class1}, #t32) in #t32;
+  let final self::Class1? #t34 = n1 in #t34 == null ?{self::Class1?} null : let final self::Class1? #t35 = self::Extension1|get#nullable1(#t34{self::Class1}) in #t35 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t35{self::Class1});
+  let final self::Class1? #t36 = n1 in #t36 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t36{self::Class1}, self::Extension1|get#nullable1(new self::Class1::•()));
+  nullable1 = let final self::Class1? #t37 = n1 in #t37 == null ?{self::Class1?} null : let final self::Class1? #t38 = self::Extension1|get#nullable1(new self::Class1::•()) in let final void #t39 = self::Extension1|set#nullable1(#t37{self::Class1}, #t38) in #t38;
+  let final self::Class1? #t40 = n1 in #t40 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t40{self::Class1}, let final self::Class1 #t41 = new self::Class1::•() in let final void #t42 = self::Extension1|set#nullable1(new self::Class1::•(), #t41) in #t41);
+  nullable1 = let final self::Class1? #t43 = n1 in #t43 == null ?{self::Class1?} null : let final self::Class1 #t44 = let final self::Class1 #t45 = new self::Class1::•() in let final void #t46 = self::Extension1|set#nullable1(new self::Class1::•(), #t45) in #t45 in let final void #t47 = self::Extension1|set#nullable1(#t43{self::Class1}, #t44) in #t44;
+  let final self::Class1? #t48 = n1 in #t48 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t48{self::Class1}, self::Extension1|nonNullable1Method(new self::Class1::•()));
+  nullable1 = let final self::Class1? #t49 = n1 in #t49 == null ?{self::Class1?} null : let final self::Class1 #t50 = self::Extension1|nonNullable1Method(new self::Class1::•()) in let final void #t51 = self::Extension1|set#nullable1(#t49{self::Class1}, #t50) in #t50;
+  let final self::Class1? #t52 = n1 in #t52 == null ?{self::Class1?} null : self::Extension1|get#nullable1(self::Extension1|nonNullable1Method(#t52{self::Class1}));
+  let final self::Class1? #t53 = n1 in #t53 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(#t53{self::Class1}), new self::Class1::•());
+  let final self::Class1? #t54 = n1 in #t54 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(#t54{self::Class1}));
+  let final self::Class1? #t55 = n1 in #t55 == null ?{self::Class1?} null : self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(self::Extension1|get#nonNullable1(#t55{self::Class1})));
+  let final self::Class1? #t56 = n1 in #t56 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(self::Extension1|get#nonNullable1(#t56{self::Class1})), new self::Class1::•());
+  nullable1 = let final self::Class1? #t57 = n1 in #t57 == null ?{self::Class1?} null : let final self::Class1 #t58 = new self::Class1::•() in let final void #t59 = self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(self::Extension1|get#nonNullable1(#t57{self::Class1})), #t58) in #t58;
+  let final self::Class1? #t60 = n1 in #t60 == null ?{self::Class1?} null : let final self::Class1? #t61 = self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(#t60{self::Class1})) in #t61 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t61{self::Class1});
+  let final self::Class1? #t62 = n1 in #t62 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t62{self::Class1}, self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(new self::Class1::•())));
+  nullable1 = let final self::Class1? #t63 = n1 in #t63 == null ?{self::Class1?} null : let final self::Class1? #t64 = self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(new self::Class1::•())) in let final void #t65 = self::Extension1|set#nullable1(#t63{self::Class1}, #t64) in #t64;
+  let final self::Class1? #t66 = n1 in #t66 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t66{self::Class1}, let final self::Class1 #t67 = new self::Class1::•() in let final void #t68 = self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(new self::Class1::•()), #t67) in #t67);
+  nullable1 = let final self::Class1? #t69 = n1 in #t69 == null ?{self::Class1?} null : let final self::Class1 #t70 = let final self::Class1 #t71 = new self::Class1::•() in let final void #t72 = self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(new self::Class1::•()), #t71) in #t71 in let final void #t73 = self::Extension1|set#nullable1(#t69{self::Class1}, #t70) in #t70;
+  let final self::Class1? #t74 = n1 in #t74 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t74{self::Class1}, self::Extension1|nonNullable1Method(self::Extension1|get#nonNullable1(new self::Class1::•())));
+  nullable1 = let final self::Class1? #t75 = n1 in #t75 == null ?{self::Class1?} null : let final self::Class1 #t76 = self::Extension1|nonNullable1Method(self::Extension1|get#nonNullable1(new self::Class1::•())) in let final void #t77 = self::Extension1|set#nullable1(#t75{self::Class1}, #t76) in #t76;
+  let final self::Class1? #t78 = n1 in #t78 == null ?{self::Class1?} null : self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(self::Extension1|nonNullable1Method(#t78{self::Class1})));
+  let final self::Class1? #t79 = n1 in #t79 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(self::Extension1|nonNullable1Method(#t79{self::Class1})), new self::Class1::•());
+  let final self::Class1? #t80 = n1 in #t80 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(self::Extension1|get#nonNullable1(self::Extension1|nonNullable1Method(#t80{self::Class1})));
+  let final self::Class1? #t81 = n1 in #t81 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t81{self::Class1}), self::Extension1|get#nullable1(new self::Class1::•()));
+  nullable1 = let final self::Class1? #t82 = n1 in #t82 == null ?{self::Class1?} null : let final self::Class1? #t83 = self::Extension1|get#nullable1(new self::Class1::•()) in let final void #t84 = self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t82{self::Class1}), #t83) in #t83;
+  let final self::Class1? #t85 = n1 in #t85 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t85{self::Class1}), let final self::Class1 #t86 = new self::Class1::•() in let final void #t87 = self::Extension1|set#nullable1(new self::Class1::•(), #t86) in #t86);
+  nullable1 = let final self::Class1? #t88 = n1 in #t88 == null ?{self::Class1?} null : let final self::Class1 #t89 = let final self::Class1 #t90 = new self::Class1::•() in let final void #t91 = self::Extension1|set#nullable1(new self::Class1::•(), #t90) in #t90 in let final void #t92 = self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t88{self::Class1}), #t89) in #t89;
+  let final self::Class1? #t93 = n1 in #t93 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t93{self::Class1}), self::Extension1|nonNullable1Method(new self::Class1::•()));
+  nullable1 = let final self::Class1? #t94 = n1 in #t94 == null ?{self::Class1?} null : let final self::Class1 #t95 = self::Extension1|nonNullable1Method(new self::Class1::•()) in let final void #t96 = self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t94{self::Class1}), #t95) in #t95;
+  let final self::Class1? #t97 = n1 in #t97 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t97{self::Class1}, let final self::Class1? #t98 = self::Extension1|get#nullable1(new self::Class1::•()) in let final void #t99 = self::Extension1|set#nullable1(new self::Class1::•(), #t98) in #t98);
+  nullable1 = let final self::Class1? #t100 = n1 in #t100 == null ?{self::Class1?} null : let final self::Class1? #t101 = let final self::Class1? #t102 = self::Extension1|get#nullable1(new self::Class1::•()) in let final void #t103 = self::Extension1|set#nullable1(new self::Class1::•(), #t102) in #t102 in let final void #t104 = self::Extension1|set#nullable1(#t100{self::Class1}, #t101) in #t101;
+  let final self::Class1? #t105 = n1 in #t105 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t105{self::Class1}, let final self::Class1 #t106 = let final self::Class1 #t107 = new self::Class1::•() in let final void #t108 = self::Extension1|set#nullable1(new self::Class1::•(), #t107) in #t107 in let final void #t109 = self::Extension1|set#nullable1(new self::Class1::•(), #t106) in #t106);
+  nullable1 = let final self::Class1? #t110 = n1 in #t110 == null ?{self::Class1?} null : let final self::Class1 #t111 = let final self::Class1 #t112 = let final self::Class1 #t113 = new self::Class1::•() in let final void #t114 = self::Extension1|set#nullable1(new self::Class1::•(), #t113) in #t113 in let final void #t115 = self::Extension1|set#nullable1(new self::Class1::•(), #t112) in #t112 in let final void #t116 = self::Extension1|set#nullable1(#t110{self::Class1}, #t111) in #t111;
+  let final self::Class1? #t117 = n1 in #t117 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t117{self::Class1}, let final self::Class1 #t118 = self::Extension1|nonNullable1Method(new self::Class1::•()) in let final void #t119 = self::Extension1|set#nullable1(new self::Class1::•(), #t118) in #t118);
+  nullable1 = let final self::Class1? #t120 = n1 in #t120 == null ?{self::Class1?} null : let final self::Class1 #t121 = let final self::Class1 #t122 = self::Extension1|nonNullable1Method(new self::Class1::•()) in let final void #t123 = self::Extension1|set#nullable1(new self::Class1::•(), #t122) in #t122 in let final void #t124 = self::Extension1|set#nullable1(#t120{self::Class1}, #t121) in #t121;
+  let final self::Class1? #t125 = n1 in #t125 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(#t125{self::Class1}), self::Extension1|get#nullable1(new self::Class1::•()));
+  nullable1 = let final self::Class1? #t126 = n1 in #t126 == null ?{self::Class1?} null : let final self::Class1? #t127 = self::Extension1|get#nullable1(new self::Class1::•()) in let final void #t128 = self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(#t126{self::Class1}), #t127) in #t127;
+  let final self::Class1? #t129 = n1 in #t129 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(#t129{self::Class1}), let final self::Class1 #t130 = new self::Class1::•() in let final void #t131 = self::Extension1|set#nullable1(new self::Class1::•(), #t130) in #t130);
+  nullable1 = let final self::Class1? #t132 = n1 in #t132 == null ?{self::Class1?} null : let final self::Class1 #t133 = let final self::Class1 #t134 = new self::Class1::•() in let final void #t135 = self::Extension1|set#nullable1(new self::Class1::•(), #t134) in #t134 in let final void #t136 = self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(#t132{self::Class1}), #t133) in #t133;
+  let final self::Class1? #t137 = n1 in #t137 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(#t137{self::Class1}), self::Extension1|nonNullable1Method(new self::Class1::•()));
+  nullable1 = let final self::Class1? #t138 = n1 in #t138 == null ?{self::Class1?} null : let final self::Class1 #t139 = self::Extension1|nonNullable1Method(new self::Class1::•()) in let final void #t140 = self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(#t138{self::Class1}), #t139) in #t139;
+  let final self::Class1? #t141 = n1 in #t141 == null ?{self::Class1?} null : self::Extension1|get#nullable1(self::Extension1|nonNullable1Method(self::Extension1|get#nonNullable1(#t141{self::Class1})));
+  let final self::Class1? #t142 = n1 in #t142 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(self::Extension1|get#nonNullable1(#t142{self::Class1})), new self::Class1::•());
+  nullable1 = let final self::Class1? #t143 = n1 in #t143 == null ?{self::Class1?} null : let final self::Class1 #t144 = new self::Class1::•() in let final void #t145 = self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(self::Extension1|get#nonNullable1(#t143{self::Class1})), #t144) in #t144;
+  let final self::Class1? #t146 = n1 in #t146 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(self::Extension1|get#nonNullable1(#t146{self::Class1})));
+  let final self::Class1? #t147 = n1 in #t147 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t147{self::Class1}, self::Extension1|get#nullable1(self::Extension1|nonNullable1Method(new self::Class1::•())));
+  nullable1 = let final self::Class1? #t148 = n1 in #t148 == null ?{self::Class1?} null : let final self::Class1? #t149 = self::Extension1|get#nullable1(self::Extension1|nonNullable1Method(new self::Class1::•())) in let final void #t150 = self::Extension1|set#nullable1(#t148{self::Class1}, #t149) in #t149;
+  let final self::Class1? #t151 = n1 in #t151 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t151{self::Class1}, let final self::Class1 #t152 = new self::Class1::•() in let final void #t153 = self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(new self::Class1::•()), #t152) in #t152);
+  nullable1 = let final self::Class1? #t154 = n1 in #t154 == null ?{self::Class1?} null : let final self::Class1 #t155 = let final self::Class1 #t156 = new self::Class1::•() in let final void #t157 = self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(new self::Class1::•()), #t156) in #t156 in let final void #t158 = self::Extension1|set#nullable1(#t154{self::Class1}, #t155) in #t155;
+  let final self::Class1? #t159 = n1 in #t159 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t159{self::Class1}, self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(new self::Class1::•())));
+  nullable1 = let final self::Class1? #t160 = n1 in #t160 == null ?{self::Class1?} null : let final self::Class1 #t161 = self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(new self::Class1::•())) in let final void #t162 = self::Extension1|set#nullable1(#t160{self::Class1}, #t161) in #t161;
+  let final self::Class1? #t163 = n1 in #t163 == null ?{self::Class1?} null : self::Extension1|get#nullable1(self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(#t163{self::Class1})));
+  let final self::Class1? #t164 = n1 in #t164 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(#t164{self::Class1})), new self::Class1::•());
+  let final self::Class1? #t165 = n1 in #t165 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(#t165{self::Class1})));
+  let final self::Class1? #t166 = n1 in #t166 == null ?{self::Class1?} null : let final self::Class1? #t167 = self::Extension1|nonNullable1Method(#t166{self::Class1}) in #t167 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t167{self::Class1});
+}
+static method indexAccess(self::Class1? n1, self::Class2? n2, self::Class3? n3) → void {
+  self::Class1? nullable1 = n1;
+  self::Class2? nullable2 = n2;
+  self::Class3? nullable3 = n3;
+  let final self::Class1? #t168 = n1 in #t168 == null ?{self::Class1?} null : self::Extension1|[](#t168{self::Class1}, nullable1);
+  let final self::Class1? #t169 = n1 in #t169 == null ?{void} null : self::Extension1|[]=(#t169{self::Class1}, nullable1, new self::Class1::•());
+  let final self::Class1? #t170 = n1 in #t170 == null ?{self::Class1?} null : let final self::Class1? #t171 = self::Extension1|[](#t170{self::Class1}, nullable1) in #t171 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t171{self::Class1});
+  let final self::Class1? #t172 = n1 in #t172 == null ?{self::Class1?} null : self::Extension1|[](self::Extension1|get#nonNullable1(#t172{self::Class1}), nullable1);
+  let final self::Class1? #t173 = n1 in #t173 == null ?{self::Class1?} null : self::Extension1|[]=(self::Extension1|get#nonNullable1(#t173{self::Class1}), nullable1, new self::Class1::•());
+  nullable1 = let final self::Class1? #t174 = n1 in #t174 == null ?{self::Class1?} null : let final self::Class1 #t175 = self::Extension1|get#nonNullable1(#t174{self::Class1}) in let final self::Class1? #t176 = nullable1 in let final self::Class1 #t177 = new self::Class1::•() in let final void #t178 = self::Extension1|[]=(#t175, #t176, #t177) in #t177;
+  let final self::Class1? #t179 = n1 in #t179 == null ?{self::Class1?} null : let final self::Class1? #t180 = self::Extension1|[](self::Extension1|get#nonNullable1(#t179{self::Class1}), nullable1) in #t180 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t180{self::Class1});
+  let final self::Class1? #t181 = n1 in #t181 == null ?{self::Class2?} null : let final self::Class2 #t182 = self::Extension1|get#nonNullable2(#t181{self::Class1}) in let final self::Class2? #t183 = nullable2 in self::Extension2|[]=(#t182, #t183, self::Extension2|+(self::Extension2|[](#t182, #t183), 0));
+  nullable2 = let final self::Class1? #t184 = n1 in #t184 == null ?{self::Class2?} null : let final self::Class2 #t185 = self::Extension1|get#nonNullable2(#t184{self::Class1}) in let final self::Class2? #t186 = nullable2 in let final self::Class2 #t187 = self::Extension2|+(self::Extension2|[](#t185, #t186), 0) in let final void #t188 = self::Extension2|[]=(#t185, #t186, #t187) in #t187;
+  let final self::Class1? #t189 = n1 in #t189 == null ?{self::Class1?} null : let final self::Class1? #t190 = nullable1 in self::Extension1|[](#t189{self::Class1}, #t190) == null ?{self::Class1?} self::Extension1|[]=(#t189{self::Class1}, #t190, nullable1) : null;
+  nullable1 = let final self::Class1? #t191 = n1 in #t191 == null ?{self::Class1?} null : let final self::Class1? #t192 = nullable1 in let final self::Class1? #t193 = self::Extension1|[](#t191{self::Class1}, #t192) in #t193 == null ?{self::Class1?} let final self::Class1? #t194 = nullable1 in let final void #t195 = self::Extension1|[]=(#t191{self::Class1}, #t192, #t194) in #t194 : #t193{self::Class1};
+  let final self::Class2? #t196 = n2 in #t196 == null ?{self::Class2?} null : let final self::Class2? #t197 = nullable2 in self::Extension2|[]=(#t196{self::Class2}, #t197, self::Extension2|+(self::Extension2|[](#t196{self::Class2}, #t197), 0));
+  nullable2 = let final self::Class2? #t198 = n2 in #t198 == null ?{self::Class2?} null : let final self::Class2? #t199 = nullable2 in let final self::Class2 #t200 = self::Extension2|+(self::Extension2|[](#t198{self::Class2}, #t199), 0) in let final void #t201 = self::Extension2|[]=(#t198{self::Class2}, #t199, #t200) in #t200;
+  let final self::Class2? #t202 = n2 in #t202 == null ?{self::Class2?} null : let final self::Class2? #t203 = nullable2 in self::Extension2|[]=(#t202{self::Class2}, #t203, self::Extension2|+(self::Extension2|[](#t202{self::Class2}, #t203), 0));
+  nullable2 = let final self::Class2? #t204 = n2 in #t204 == null ?{self::Class2?} null : let final self::Class2? #t205 = nullable2 in let final self::Class2 #t206 = self::Extension2|+(self::Extension2|[](#t204{self::Class2}, #t205), 0) in let final void #t207 = self::Extension2|[]=(#t204{self::Class2}, #t205, #t206) in #t206;
+  let final self::Class2? #t208 = n2 in #t208 == null ?{self::Class2?} null : let final self::Class2? #t209 = nullable2 in self::Extension2|[]=(#t208{self::Class2}, #t209, self::Extension2|+(self::Extension2|[](#t208{self::Class2}, #t209), 1));
+  nullable2 = let final self::Class2? #t210 = n2 in #t210 == null ?{self::Class2?} null : let final self::Class2? #t211 = nullable2 in let final self::Class2 #t212 = self::Extension2|[](#t210{self::Class2}, #t211) in let final void #t213 = self::Extension2|[]=(#t210{self::Class2}, #t211, self::Extension2|+(#t212, 1)) in #t212;
+  let final self::Class2? #t214 = n2 in #t214 == null ?{self::Class2?} null : let final self::Class2? #t215 = nullable2 in let final self::Class2 #t216 = self::Extension2|+(self::Extension2|[](#t214{self::Class2}, #t215), 1) in let final void #t217 = self::Extension2|[]=(#t214{self::Class2}, #t215, #t216) in #t216;
+  nullable2 = let final self::Class2? #t218 = n2 in #t218 == null ?{self::Class2?} null : let final self::Class2? #t219 = nullable2 in let final self::Class2 #t220 = self::Extension2|+(self::Extension2|[](#t218{self::Class2}, #t219), 1) in let final void #t221 = self::Extension2|[]=(#t218{self::Class2}, #t219, #t220) in #t220;
+  let final self::Class1? #t222 = n1 in #t222 == null ?{self::Class2?} null : let final self::Class2 #t223 = self::Extension1|get#nonNullable2(#t222{self::Class1}) in let final self::Class2? #t224 = nullable2 in self::Extension2|[]=(#t223, #t224, self::Extension2|+(self::Extension2|[](#t223, #t224), 1));
+  nullable2 = let final self::Class1? #t225 = n1 in #t225 == null ?{self::Class2?} null : let final self::Class2 #t226 = self::Extension1|get#nonNullable2(#t225{self::Class1}) in let final self::Class2? #t227 = nullable2 in let final self::Class2 #t228 = self::Extension2|[](#t226, #t227) in let final void #t229 = self::Extension2|[]=(#t226, #t227, self::Extension2|+(#t228, 1)) in #t228;
+  let final self::Class1? #t230 = n1 in #t230 == null ?{self::Class2?} null : let final self::Class2 #t231 = self::Extension1|get#nonNullable2(#t230{self::Class1}) in let final self::Class2? #t232 = nullable2 in let final self::Class2 #t233 = self::Extension2|+(self::Extension2|[](#t231, #t232), 1) in let final void #t234 = self::Extension2|[]=(#t231, #t232, #t233) in #t233;
+  nullable2 = let final self::Class1? #t235 = n1 in #t235 == null ?{self::Class2?} null : let final self::Class2 #t236 = self::Extension1|get#nonNullable2(#t235{self::Class1}) in let final self::Class2? #t237 = nullable2 in let final self::Class2 #t238 = self::Extension2|+(self::Extension2|[](#t236, #t237), 1) in let final void #t239 = self::Extension2|[]=(#t236, #t237, #t238) in #t238;
+  let final self::Class1? #t240 = n1 in #t240 == null ?{self::Class2?} null : self::Extension2|[](self::Extension2|[](self::Extension1|get#nonNullable2(#t240{self::Class1}), nullable2), nullable2);
+  let final self::Class1? #t241 = n1 in #t241 == null ?{self::Class2?} null : self::Extension2|[]=(self::Extension2|[](self::Extension1|get#nonNullable2(#t241{self::Class1}), nullable2), nullable2, new self::Class2::•());
+  nullable2 = let final self::Class1? #t242 = n1 in #t242 == null ?{self::Class2?} null : let final self::Class2 #t243 = self::Extension2|[](self::Extension1|get#nonNullable2(#t242{self::Class1}), nullable2) in let final self::Class2? #t244 = nullable2 in let final self::Class2 #t245 = new self::Class2::•() in let final void #t246 = self::Extension2|[]=(#t243, #t244, #t245) in #t245;
+  let final self::Class1? #t247 = n1 in #t247 == null ?{self::Class2?} null : let final self::Class2? #t248 = self::Extension2|[](self::Extension2|[](self::Extension1|get#nonNullable2(#t247{self::Class1}), nullable2), nullable2) in #t248 == null ?{self::Class2?} null : self::Extension2|nonNullable2Method(#t248{self::Class2});
+  let final self::Class1? #t249 = n1 in #t249 == null ?{self::Class2?} null : let final self::Class2 #t250 = self::Extension2|[](self::Extension1|get#nonNullable2(#t249{self::Class1}), nullable2) in let final self::Class2? #t251 = nullable2 in self::Extension2|[]=(#t250, #t251, self::Extension2|+(self::Extension2|[](#t250, #t251), 0));
+  nullable2 = let final self::Class1? #t252 = n1 in #t252 == null ?{self::Class2?} null : let final self::Class2 #t253 = self::Extension2|[](self::Extension1|get#nonNullable2(#t252{self::Class1}), nullable2) in let final self::Class2? #t254 = nullable2 in let final self::Class2 #t255 = self::Extension2|+(self::Extension2|[](#t253, #t254), 0) in let final void #t256 = self::Extension2|[]=(#t253, #t254, #t255) in #t255;
+  let final self::Class1? #t257 = n1 in #t257 == null ?{self::Class2?} null : let final self::Class2 #t258 = self::Extension2|[](self::Extension1|get#nonNullable2(#t257{self::Class1}), nullable2) in let final self::Class2? #t259 = nullable2 in self::Extension2|[]=(#t258, #t259, self::Extension2|+(self::Extension2|[](#t258, #t259), 1));
+  nullable2 = let final self::Class1? #t260 = n1 in #t260 == null ?{self::Class2?} null : let final self::Class2 #t261 = self::Extension2|[](self::Extension1|get#nonNullable2(#t260{self::Class1}), nullable2) in let final self::Class2? #t262 = nullable2 in let final self::Class2 #t263 = self::Extension2|[](#t261, #t262) in let final void #t264 = self::Extension2|[]=(#t261, #t262, self::Extension2|+(#t263, 1)) in #t263;
+  let final self::Class1? #t265 = n1 in #t265 == null ?{self::Class2?} null : let final self::Class2 #t266 = self::Extension2|[](self::Extension1|get#nonNullable2(#t265{self::Class1}), nullable2) in let final self::Class2? #t267 = nullable2 in let final self::Class2 #t268 = self::Extension2|+(self::Extension2|[](#t266, #t267), 1) in let final void #t269 = self::Extension2|[]=(#t266, #t267, #t268) in #t268;
+  nullable2 = let final self::Class1? #t270 = n1 in #t270 == null ?{self::Class2?} null : let final self::Class2 #t271 = self::Extension2|[](self::Extension1|get#nonNullable2(#t270{self::Class1}), nullable2) in let final self::Class2? #t272 = nullable2 in let final self::Class2 #t273 = self::Extension2|+(self::Extension2|[](#t271, #t272), 1) in let final void #t274 = self::Extension2|[]=(#t271, #t272, #t273) in #t273;
+  let final self::Class1? #t275 = n1 in #t275 == null ?{self::Class1?} null : let final self::Class1? #t276 = self::Extension1|[](#t275{self::Class1}, nullable1) in #t276 == null ?{self::Class1?} null : self::Extension1|[](#t276{self::Class1}, nullable1);
+  let final self::Class1? #t277 = n1 in #t277 == null ?{self::Class1?} null : let final self::Class1? #t278 = self::Extension1|[](#t277{self::Class1}, nullable1) in #t278 == null ?{self::Class1?} null : self::Extension1|[]=(#t278{self::Class1}, nullable1, new self::Class1::•());
+  nullable1 = let final self::Class1? #t279 = n1 in #t279 == null ?{self::Class1?} null : let final self::Class1? #t280 = self::Extension1|[](#t279{self::Class1}, nullable1) in #t280 == null ?{self::Class1?} null : let final self::Class1? #t281 = nullable1 in let final self::Class1 #t282 = new self::Class1::•() in let final void #t283 = self::Extension1|[]=(#t280{self::Class1}, #t281, #t282) in #t282;
+  let final self::Class1? #t284 = n1 in #t284 == null ?{self::Class1?} null : let final self::Class1? #t285 = self::Extension1|[](#t284{self::Class1}, nullable1) in #t285 == null ?{self::Class1?} null : let final self::Class1? #t286 = self::Extension1|[](#t285{self::Class1}, nullable1) in #t286 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t286{self::Class1});
+  nullable1 = let final self::Class1? #t287 = n1 in #t287 == null ?{self::Class1?} null : let final self::Class1? #t288 = self::Extension1|[](#t287{self::Class1}, nullable1) in #t288 == null ?{self::Class1?} null : let final self::Class1? #t289 = self::Extension1|[](#t288{self::Class1}, nullable1) in #t289 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t289{self::Class1});
+  let final self::Class1? #t290 = n1 in #t290 == null ?{self::Class1?} null : let final self::Class1? #t291 = self::Extension1|[](#t290{self::Class1}, nullable1) in #t291 == null ?{self::Class1?} null : let final self::Class1? #t292 = nullable1 in self::Extension1|[](#t291{self::Class1}, #t292) == null ?{self::Class1?} self::Extension1|[]=(#t291{self::Class1}, #t292, nullable1) : null;
+  nullable1 = let final self::Class1? #t293 = n1 in #t293 == null ?{self::Class1?} null : let final self::Class1? #t294 = self::Extension1|[](#t293{self::Class1}, nullable1) in #t294 == null ?{self::Class1?} null : let final self::Class1? #t295 = nullable1 in let final self::Class1? #t296 = self::Extension1|[](#t294{self::Class1}, #t295) in #t296 == null ?{self::Class1?} let final self::Class1? #t297 = nullable1 in let final void #t298 = self::Extension1|[]=(#t294{self::Class1}, #t295, #t297) in #t297 : #t296{self::Class1};
+  let final self::Class3? #t299 = n3 in #t299 == null ?{self::Class2?} null : let final self::Class2? #t300 = self::Extension3|[](#t299{self::Class3}, nullable3) in #t300 == null ?{self::Class2?} null : let final self::Class2? #t301 = nullable2 in self::Extension2|[]=(#t300{self::Class2}, #t301, self::Extension2|+(self::Extension2|[](#t300{self::Class2}, #t301), 0));
+  nullable2 = let final self::Class3? #t302 = n3 in #t302 == null ?{self::Class2?} null : let final self::Class2? #t303 = self::Extension3|[](#t302{self::Class3}, nullable3) in #t303 == null ?{self::Class2?} null : let final self::Class2? #t304 = nullable2 in let final self::Class2 #t305 = self::Extension2|+(self::Extension2|[](#t303{self::Class2}, #t304), 0) in let final void #t306 = self::Extension2|[]=(#t303{self::Class2}, #t304, #t305) in #t305;
+  let final self::Class3? #t307 = n3 in #t307 == null ?{self::Class2?} null : let final self::Class2? #t308 = self::Extension3|[](#t307{self::Class3}, nullable3) in #t308 == null ?{self::Class2?} null : let final self::Class2? #t309 = nullable2 in self::Extension2|[]=(#t308{self::Class2}, #t309, self::Extension2|+(self::Extension2|[](#t308{self::Class2}, #t309), 1));
+  nullable2 = let final self::Class3? #t310 = n3 in #t310 == null ?{self::Class2?} null : let final self::Class2? #t311 = self::Extension3|[](#t310{self::Class3}, nullable3) in #t311 == null ?{self::Class2?} null : let final self::Class2? #t312 = nullable2 in let final self::Class2 #t313 = self::Extension2|[](#t311{self::Class2}, #t312) in let final void #t314 = self::Extension2|[]=(#t311{self::Class2}, #t312, self::Extension2|+(#t313, 1)) in #t313;
+  let final self::Class3? #t315 = n3 in #t315 == null ?{self::Class2?} null : let final self::Class2? #t316 = self::Extension3|[](#t315{self::Class3}, nullable3) in #t316 == null ?{self::Class2?} null : let final self::Class2? #t317 = nullable2 in let final self::Class2 #t318 = self::Extension2|+(self::Extension2|[](#t316{self::Class2}, #t317), 1) in let final void #t319 = self::Extension2|[]=(#t316{self::Class2}, #t317, #t318) in #t318;
+  nullable2 = let final self::Class3? #t320 = n3 in #t320 == null ?{self::Class2?} null : let final self::Class2? #t321 = self::Extension3|[](#t320{self::Class3}, nullable3) in #t321 == null ?{self::Class2?} null : let final self::Class2? #t322 = nullable2 in let final self::Class2 #t323 = self::Extension2|+(self::Extension2|[](#t321{self::Class2}, #t322), 1) in let final void #t324 = self::Extension2|[]=(#t321{self::Class2}, #t322, #t323) in #t323;
+}
+static method operatorAccess(self::Class1? n1, self::Class2? n2) → void {
+  self::Class2? nullable2 = n2;
+  self::throws(() → void => invalid-expression "pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart:244:45: Error: Operator '+' cannot be called on 'Class1?' because it is potentially null.
+ - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart'.
+  throws(() => Extension1(n1)?.nonNullable1 + 0);
+                                            ^" in self::Extension1|+(let final self::Class1? #t325 = n1 in #t325 == null ?{self::Class1?} null : self::Extension1|get#nonNullable1(#t325{self::Class1}), 0));
+  self::throws(() → void => invalid-expression "pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart:245:16: Error: Operator 'unary-' cannot be called on 'Class1?' because it is potentially null.
+ - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_explicit_extension.dart'.
+  throws(() => -Extension1(n1)?.nonNullable1);
+               ^" in self::Extension1|unary-(let final self::Class1? #t326 = n1 in #t326 == null ?{self::Class1?} null : self::Extension1|get#nonNullable1(#t326{self::Class1})));
+  let final self::Class2? #t327 = n2 in #t327 == null ?{self::Class2?} null : self::Extension2|set#nonNullable2(#t327{self::Class2}, self::Extension2|+(self::Extension2|get#nonNullable2(#t327{self::Class2}), 0));
+  nullable2 = let final self::Class2? #t328 = n2 in #t328 == null ?{self::Class2?} null : let final self::Class2 #t329 = self::Extension2|+(self::Extension2|get#nonNullable2(#t328{self::Class2}), 0) in let final void #t330 = self::Extension2|set#nonNullable2(#t328{self::Class2}, #t329) in #t329;
+  let final self::Class2? #t331 = n2 in #t331 == null ?{self::Class2?} null : let final self::Class2 #t332 = self::Extension2|get#nonNullable2(#t331{self::Class2}) in self::Extension2|set#nonNullable2(#t332, self::Extension2|+(self::Extension2|get#nonNullable2(#t332), 0));
+  nullable2 = let final self::Class2? #t333 = n2 in #t333 == null ?{self::Class2?} null : let final self::Class2 #t334 = self::Extension2|get#nonNullable2(#t333{self::Class2}) in let final self::Class2 #t335 = self::Extension2|+(self::Extension2|get#nonNullable2(#t334), 0) in let final void #t336 = self::Extension2|set#nonNullable2(#t334, #t335) in #t335;
+  let final self::Class2? #t337 = n2 in #t337 == null ?{self::Class2?} null : self::Extension2|set#nonNullable2(#t337{self::Class2}, self::Extension2|+(self::Extension2|get#nonNullable2(#t337{self::Class2}), 1));
+  nullable2 = let final self::Class2? #t338 = n2 in #t338 == null ?{self::Class2?} null : let final self::Class2 #t339 = self::Extension2|get#nonNullable2(#t338{self::Class2}) in let final self::Class2 #t340 = let final self::Class2 #t341 = self::Extension2|+(#t339, 1) in let final void #t342 = self::Extension2|set#nonNullable2(#t338{self::Class2}, #t341) in #t341 in #t339;
+  let final self::Class2? #t343 = n2 in #t343 == null ?{self::Class2?} null : let final self::Class2 #t344 = self::Extension2|+(self::Extension2|get#nonNullable2(#t343{self::Class2}), 1) in let final void #t345 = self::Extension2|set#nonNullable2(#t343{self::Class2}, #t344) in #t344;
+  nullable2 = let final self::Class2? #t346 = n2 in #t346 == null ?{self::Class2?} null : let final self::Class2 #t347 = self::Extension2|+(self::Extension2|get#nonNullable2(#t346{self::Class2}), 1) in let final void #t348 = self::Extension2|set#nonNullable2(#t346{self::Class2}, #t347) in #t347;
+}
+static method ifNull(self::Class1? n1) → void {
+  self::Class1? nullable1 = n1;
+  let final self::Class1? #t349 = n1 in #t349 == null ?{self::Class1?} null : self::Extension1|get#nullable1(#t349) == null ?{self::Class1} self::Extension1|set#nullable1(#t349, n1{self::Class1}) : null;
+  n1 = let final self::Class1? #t350 = n1 in #t350 == null ?{self::Class1?} null : let final self::Class1? #t351 = self::Extension1|get#nullable1(#t350) in #t351 == null ?{self::Class1} let final self::Class1 #t352 = n1{self::Class1} in let final void #t353 = self::Extension1|set#nullable1(#t350, #t352) in #t352 : #t351{self::Class1};
+  let final self::Class1? #t354 = n1 in #t354 == null ?{self::Class1?} null : let final self::Class1 #t355 = self::Extension1|get#nonNullable1(#t354{self::Class1}) in self::Extension1|get#nullable1(#t355) == null ?{self::Class1} self::Extension1|set#nullable1(#t355, n1{self::Class1}) : null;
+  n1 = let final self::Class1? #t356 = n1 in #t356 == null ?{self::Class1?} null : let final self::Class1 #t357 = self::Extension1|get#nonNullable1(#t356{self::Class1}) in let final self::Class1? #t358 = self::Extension1|get#nullable1(#t357) in #t358 == null ?{self::Class1} let final self::Class1 #t359 = n1{self::Class1} in let final void #t360 = self::Extension1|set#nullable1(#t357, #t359) in #t359 : #t358{self::Class1};
+  let final self::Class1? #t361 = n1 in #t361 == null ?{self::Class1?} null : let final self::Class1 #t362 = self::Extension1|get#nonNullable1(#t361{self::Class1}) in let final self::Class1 #t363 = n1{self::Class1} in self::Extension1|[](#t362, #t363) == null ?{self::Class1} self::Extension1|[]=(#t362, #t363, n1{self::Class1}) : null;
+  n1 = let final self::Class1? #t364 = n1 in #t364 == null ?{self::Class1?} null : let final self::Class1 #t365 = self::Extension1|get#nonNullable1(#t364{self::Class1}) in let final self::Class1 #t366 = n1{self::Class1} in let final self::Class1? #t367 = self::Extension1|[](#t365, #t366) in #t367 == null ?{self::Class1} let final self::Class1 #t368 = n1{self::Class1} in let final void #t369 = self::Extension1|[]=(#t365, #t366, #t368) in #t368 : #t367{self::Class1};
+}
+static method throws(() → void f) → void {
+  try {
+    f(){() → void};
+  }
+  on core::Object catch(final core::Object _) {
+    return;
+  }
+  throw "Expected exception.";
+}
diff --git a/pkg/front_end/testcases/nnbd/null_shorting_extension.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/null_shorting_extension.dart.weak.modular.expect
new file mode 100644
index 0000000..954b4c0
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/null_shorting_extension.dart.weak.modular.expect
@@ -0,0 +1,298 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/null_shorting_extension.dart:93:47: Error: Property 'nullable1' cannot be accessed on 'Class1?' because it is potentially null.
+//  - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_extension.dart'.
+// Try accessing using ?. instead.
+//   throws(() => (n1?.nullable1 = new Class1()).nullable1);
+//                                               ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_extension.dart:94:43: Error: Property 'nullable1' cannot be accessed on 'Class1?' because it is potentially null.
+//  - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_extension.dart'.
+// Try accessing using ?. instead.
+//   throws(() => (n1?.nonNullable1Method()).nullable1);
+//                                           ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_extension.dart:226:33: Error: Operator '+' cannot be called on 'Class1?' because it is potentially null.
+//  - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_extension.dart'.
+//   throws(() => n1?.nonNullable1 + 0);
+//                                 ^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_extension.dart:227:16: Error: Operator 'unary-' cannot be called on 'Class1?' because it is potentially null.
+//  - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_extension.dart'.
+//   throws(() => -n1?.nonNullable1);
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+  get property() → self::Class1?
+    return null;
+  set property(self::Class1? value) → void {}
+  get property1() → self::Class1
+    return new self::Class1::•();
+  get property2() → self::Class2
+    return new self::Class2::•();
+}
+class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2
+    : super core::Object::•()
+    ;
+  get property() → self::Class2
+    return this;
+  set property(self::Class2 value) → void {}
+}
+class Class3 extends core::Object {
+  synthetic constructor •() → self::Class3
+    : super core::Object::•()
+    ;
+  get property() → self::Class2?
+    return null;
+}
+extension Extension1 on self::Class1 {
+  get nullable1 = self::Extension1|get#nullable1;
+  method nonNullable1Method = self::Extension1|nonNullable1Method;
+  tearoff nonNullable1Method = self::Extension1|get#nonNullable1Method;
+  operator [] = self::Extension1|[];
+  operator []= = self::Extension1|[]=;
+  operator + = self::Extension1|+;
+  operator unary- = self::Extension1|unary-;
+  get nonNullable1 = self::Extension1|get#nonNullable1;
+  get nonNullable2 = self::Extension1|get#nonNullable2;
+  set nullable1 = self::Extension1|set#nullable1;
+}
+extension Extension2 on self::Class2 {
+  method nonNullable2Method = self::Extension2|nonNullable2Method;
+  tearoff nonNullable2Method = self::Extension2|get#nonNullable2Method;
+  operator [] = self::Extension2|[];
+  operator []= = self::Extension2|[]=;
+  operator + = self::Extension2|+;
+  operator unary- = self::Extension2|unary-;
+  get nonNullable2 = self::Extension2|get#nonNullable2;
+  set nonNullable2 = self::Extension2|set#nonNullable2;
+}
+extension Extension3 on self::Class3 {
+  operator [] = self::Extension3|[];
+}
+static method Extension1|get#nullable1(lowered final self::Class1 #this) → self::Class1?
+  return #this.{self::Class1::property1}{self::Class1};
+static method Extension1|set#nullable1(lowered final self::Class1 #this, self::Class1? value) → void {
+  #this.{self::Class1::property} = value;
+}
+static method Extension1|nonNullable1Method(lowered final self::Class1 #this) → self::Class1
+  return self::Extension1|get#nonNullable1(#this);
+static method Extension1|get#nonNullable1Method(lowered final self::Class1 #this) → () → self::Class1
+  return () → self::Class1 => self::Extension1|nonNullable1Method(#this);
+static method Extension1|[](lowered final self::Class1 #this, self::Class1? key) → self::Class1?
+  return self::Extension1|get#nullable1(#this);
+static method Extension1|[]=(lowered final self::Class1 #this, self::Class1? key, self::Class1? value) → void {
+  #this.{self::Class1::property} = value;
+}
+static method Extension1|+(lowered final self::Class1 #this, core::int value) → self::Class1?
+  return self::Extension1|get#nullable1(#this);
+static method Extension1|unary-(lowered final self::Class1 #this) → self::Class1?
+  return self::Extension1|get#nullable1(#this);
+static method Extension1|get#nonNullable1(lowered final self::Class1 #this) → self::Class1
+  return #this.{self::Class1::property1}{self::Class1};
+static method Extension1|get#nonNullable2(lowered final self::Class1 #this) → self::Class2
+  return #this.{self::Class1::property2}{self::Class2};
+static method Extension2|nonNullable2Method(lowered final self::Class2 #this) → self::Class2
+  return self::Extension2|get#nonNullable2(#this);
+static method Extension2|get#nonNullable2Method(lowered final self::Class2 #this) → () → self::Class2
+  return () → self::Class2 => self::Extension2|nonNullable2Method(#this);
+static method Extension2|[](lowered final self::Class2 #this, self::Class2? key) → self::Class2
+  return #this.{self::Class2::property}{self::Class2};
+static method Extension2|[]=(lowered final self::Class2 #this, self::Class2? key, self::Class2? value) → void
+  return #this.{self::Class2::property}{self::Class2};
+static method Extension2|+(lowered final self::Class2 #this, core::int value) → self::Class2
+  return #this.{self::Class2::property}{self::Class2};
+static method Extension2|unary-(lowered final self::Class2 #this) → self::Class2
+  return #this.{self::Class2::property}{self::Class2};
+static method Extension2|get#nonNullable2(lowered final self::Class2 #this) → self::Class2
+  return #this.{self::Class2::property}{self::Class2};
+static method Extension2|set#nonNullable2(lowered final self::Class2 #this, self::Class2 value) → void {
+  #this.{self::Class2::property} = value;
+}
+static method Extension3|[](lowered final self::Class3 #this, self::Class3? key) → self::Class2?
+  return #this.{self::Class3::property}{self::Class2?};
+static method main() → dynamic {
+  self::propertyAccess(null);
+  self::indexAccess(null, null, null);
+  self::operatorAccess(null, null);
+  self::ifNull(null);
+}
+static method propertyAccess(self::Class1? n1) → void {
+  self::Class1? nullable1 = n1;
+  let final self::Class1? #t1 = n1 in #t1 == null ?{self::Class1?} null : self::Extension1|get#nullable1(#t1{self::Class1});
+  let final self::Class1? #t2 = n1 in #t2 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t2{self::Class1}, new self::Class1::•());
+  nullable1 = let final self::Class1? #t3 = n1 in #t3 == null ?{self::Class1?} null : let final self::Class1 #t4 = new self::Class1::•() in let final void #t5 = self::Extension1|set#nullable1(#t3{self::Class1}, #t4) in #t4;
+  let final self::Class1? #t6 = n1 in #t6 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t6{self::Class1});
+  let final self::Class1? #t7 = n1 in #t7 == null ?{self::Class1?} null : self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(#t7{self::Class1}));
+  let final self::Class1? #t8 = n1 in #t8 == null ?{self::Class1?} null : let final self::Class1? #t9 = self::Extension1|get#nullable1(#t8{self::Class1}) in #t9 == null ?{self::Class1?} null : self::Extension1|get#nullable1(#t9{self::Class1});
+  let final self::Class1? #t10 = n1 in #t10 == null ?{self::Class1?} null : let final self::Class1? #t11 = self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(#t10{self::Class1})) in #t11 == null ?{self::Class1?} null : self::Extension1|get#nullable1(#t11{self::Class1});
+  let final self::Class1? #t12 = n1 in #t12 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t12{self::Class1}), new self::Class1::•());
+  let final self::Class1? #t13 = n1 in #t13 == null ?{self::Class1?} null : let final self::Class1? #t14 = self::Extension1|get#nullable1(#t13{self::Class1}) in #t14 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t14{self::Class1}, new self::Class1::•());
+  let final self::Class1? #t15 = n1 in #t15 == null ?{self::Class1?} null : let final self::Class1? #t16 = self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(#t15{self::Class1})) in #t16 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t16{self::Class1}, new self::Class1::•());
+  let final self::Class1? #t17 = let final self::Class1? #t18 = n1 in #t18 == null ?{self::Class1?} null : self::Extension1|get#nullable1(#t18{self::Class1}) in #t17 == null ?{self::Class1?} null : self::Extension1|get#nullable1(#t17{self::Class1});
+  self::throws(() → void => invalid-expression "pkg/front_end/testcases/nnbd/null_shorting_extension.dart:93:47: Error: Property 'nullable1' cannot be accessed on 'Class1?' because it is potentially null.
+ - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_extension.dart'.
+Try accessing using ?. instead.
+  throws(() => (n1?.nullable1 = new Class1()).nullable1);
+                                              ^^^^^^^^^" in self::Extension1|get#nullable1(let final self::Class1? #t19 = n1 in #t19 == null ?{self::Class1?} null : let final self::Class1 #t20 = new self::Class1::•() in let final void #t21 = self::Extension1|set#nullable1(#t19{self::Class1}, #t20) in #t20));
+  self::throws(() → void => invalid-expression "pkg/front_end/testcases/nnbd/null_shorting_extension.dart:94:43: Error: Property 'nullable1' cannot be accessed on 'Class1?' because it is potentially null.
+ - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_extension.dart'.
+Try accessing using ?. instead.
+  throws(() => (n1?.nonNullable1Method()).nullable1);
+                                          ^^^^^^^^^" in self::Extension1|get#nullable1(let final self::Class1? #t22 = n1 in #t22 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t22{self::Class1})));
+  nullable1 = let final self::Class1? #t23 = n1 in #t23 == null ?{self::Class1?} null : let final self::Class1 #t24 = new self::Class1::•() in let final void #t25 = self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t23{self::Class1}), #t24) in #t24;
+  nullable1 = let final self::Class1? #t26 = n1 in #t26 == null ?{self::Class1?} null : let final self::Class1? #t27 = self::Extension1|get#nullable1(#t26{self::Class1}) in #t27 == null ?{self::Class1?} null : let final self::Class1 #t28 = new self::Class1::•() in let final void #t29 = self::Extension1|set#nullable1(#t27{self::Class1}, #t28) in #t28;
+  nullable1 = let final self::Class1? #t30 = n1 in #t30 == null ?{self::Class1?} null : let final self::Class1? #t31 = self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(#t30{self::Class1})) in #t31 == null ?{self::Class1?} null : let final self::Class1 #t32 = new self::Class1::•() in let final void #t33 = self::Extension1|set#nullable1(#t31{self::Class1}, #t32) in #t32;
+  let final self::Class1? #t34 = n1 in #t34 == null ?{self::Class1?} null : let final self::Class1? #t35 = self::Extension1|get#nullable1(#t34{self::Class1}) in #t35 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t35{self::Class1});
+  let final self::Class1? #t36 = n1 in #t36 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t36{self::Class1}, self::Extension1|get#nullable1(new self::Class1::•()));
+  nullable1 = let final self::Class1? #t37 = n1 in #t37 == null ?{self::Class1?} null : let final self::Class1? #t38 = self::Extension1|get#nullable1(new self::Class1::•()) in let final void #t39 = self::Extension1|set#nullable1(#t37{self::Class1}, #t38) in #t38;
+  let final self::Class1? #t40 = n1 in #t40 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t40{self::Class1}, let final self::Class1 #t41 = new self::Class1::•() in let final void #t42 = self::Extension1|set#nullable1(new self::Class1::•(), #t41) in #t41);
+  nullable1 = let final self::Class1? #t43 = n1 in #t43 == null ?{self::Class1?} null : let final self::Class1 #t44 = let final self::Class1 #t45 = new self::Class1::•() in let final void #t46 = self::Extension1|set#nullable1(new self::Class1::•(), #t45) in #t45 in let final void #t47 = self::Extension1|set#nullable1(#t43{self::Class1}, #t44) in #t44;
+  let final self::Class1? #t48 = n1 in #t48 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t48{self::Class1}, self::Extension1|nonNullable1Method(new self::Class1::•()));
+  nullable1 = let final self::Class1? #t49 = n1 in #t49 == null ?{self::Class1?} null : let final self::Class1 #t50 = self::Extension1|nonNullable1Method(new self::Class1::•()) in let final void #t51 = self::Extension1|set#nullable1(#t49{self::Class1}, #t50) in #t50;
+  let final self::Class1? #t52 = n1 in #t52 == null ?{self::Class1?} null : self::Extension1|get#nullable1(self::Extension1|nonNullable1Method(#t52{self::Class1}));
+  let final self::Class1? #t53 = n1 in #t53 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(#t53{self::Class1}), new self::Class1::•());
+  let final self::Class1? #t54 = n1 in #t54 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(#t54{self::Class1}));
+  let final self::Class1? #t55 = n1 in #t55 == null ?{self::Class1?} null : self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(self::Extension1|get#nonNullable1(#t55{self::Class1})));
+  let final self::Class1? #t56 = n1 in #t56 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(self::Extension1|get#nonNullable1(#t56{self::Class1})), new self::Class1::•());
+  nullable1 = let final self::Class1? #t57 = n1 in #t57 == null ?{self::Class1?} null : let final self::Class1 #t58 = new self::Class1::•() in let final void #t59 = self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(self::Extension1|get#nonNullable1(#t57{self::Class1})), #t58) in #t58;
+  let final self::Class1? #t60 = n1 in #t60 == null ?{self::Class1?} null : let final self::Class1? #t61 = self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(#t60{self::Class1})) in #t61 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t61{self::Class1});
+  let final self::Class1? #t62 = n1 in #t62 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t62{self::Class1}, self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(new self::Class1::•())));
+  nullable1 = let final self::Class1? #t63 = n1 in #t63 == null ?{self::Class1?} null : let final self::Class1? #t64 = self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(new self::Class1::•())) in let final void #t65 = self::Extension1|set#nullable1(#t63{self::Class1}, #t64) in #t64;
+  let final self::Class1? #t66 = n1 in #t66 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t66{self::Class1}, let final self::Class1 #t67 = new self::Class1::•() in let final void #t68 = self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(new self::Class1::•()), #t67) in #t67);
+  nullable1 = let final self::Class1? #t69 = n1 in #t69 == null ?{self::Class1?} null : let final self::Class1 #t70 = let final self::Class1 #t71 = new self::Class1::•() in let final void #t72 = self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(new self::Class1::•()), #t71) in #t71 in let final void #t73 = self::Extension1|set#nullable1(#t69{self::Class1}, #t70) in #t70;
+  let final self::Class1? #t74 = n1 in #t74 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t74{self::Class1}, self::Extension1|nonNullable1Method(self::Extension1|get#nonNullable1(new self::Class1::•())));
+  nullable1 = let final self::Class1? #t75 = n1 in #t75 == null ?{self::Class1?} null : let final self::Class1 #t76 = self::Extension1|nonNullable1Method(self::Extension1|get#nonNullable1(new self::Class1::•())) in let final void #t77 = self::Extension1|set#nullable1(#t75{self::Class1}, #t76) in #t76;
+  let final self::Class1? #t78 = n1 in #t78 == null ?{self::Class1?} null : self::Extension1|get#nullable1(self::Extension1|get#nonNullable1(self::Extension1|nonNullable1Method(#t78{self::Class1})));
+  let final self::Class1? #t79 = n1 in #t79 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(self::Extension1|nonNullable1Method(#t79{self::Class1})), new self::Class1::•());
+  let final self::Class1? #t80 = n1 in #t80 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(self::Extension1|get#nonNullable1(self::Extension1|nonNullable1Method(#t80{self::Class1})));
+  let final self::Class1? #t81 = n1 in #t81 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t81{self::Class1}), self::Extension1|get#nullable1(new self::Class1::•()));
+  nullable1 = let final self::Class1? #t82 = n1 in #t82 == null ?{self::Class1?} null : let final self::Class1? #t83 = self::Extension1|get#nullable1(new self::Class1::•()) in let final void #t84 = self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t82{self::Class1}), #t83) in #t83;
+  let final self::Class1? #t85 = n1 in #t85 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t85{self::Class1}), let final self::Class1 #t86 = new self::Class1::•() in let final void #t87 = self::Extension1|set#nullable1(new self::Class1::•(), #t86) in #t86);
+  nullable1 = let final self::Class1? #t88 = n1 in #t88 == null ?{self::Class1?} null : let final self::Class1 #t89 = let final self::Class1 #t90 = new self::Class1::•() in let final void #t91 = self::Extension1|set#nullable1(new self::Class1::•(), #t90) in #t90 in let final void #t92 = self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t88{self::Class1}), #t89) in #t89;
+  let final self::Class1? #t93 = n1 in #t93 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t93{self::Class1}), self::Extension1|nonNullable1Method(new self::Class1::•()));
+  nullable1 = let final self::Class1? #t94 = n1 in #t94 == null ?{self::Class1?} null : let final self::Class1 #t95 = self::Extension1|nonNullable1Method(new self::Class1::•()) in let final void #t96 = self::Extension1|set#nullable1(self::Extension1|get#nonNullable1(#t94{self::Class1}), #t95) in #t95;
+  let final self::Class1? #t97 = n1 in #t97 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t97{self::Class1}, let final self::Class1? #t98 = self::Extension1|get#nullable1(new self::Class1::•()) in let final void #t99 = self::Extension1|set#nullable1(new self::Class1::•(), #t98) in #t98);
+  nullable1 = let final self::Class1? #t100 = n1 in #t100 == null ?{self::Class1?} null : let final self::Class1? #t101 = let final self::Class1? #t102 = self::Extension1|get#nullable1(new self::Class1::•()) in let final void #t103 = self::Extension1|set#nullable1(new self::Class1::•(), #t102) in #t102 in let final void #t104 = self::Extension1|set#nullable1(#t100{self::Class1}, #t101) in #t101;
+  let final self::Class1? #t105 = n1 in #t105 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t105{self::Class1}, let final self::Class1 #t106 = let final self::Class1 #t107 = new self::Class1::•() in let final void #t108 = self::Extension1|set#nullable1(new self::Class1::•(), #t107) in #t107 in let final void #t109 = self::Extension1|set#nullable1(new self::Class1::•(), #t106) in #t106);
+  nullable1 = let final self::Class1? #t110 = n1 in #t110 == null ?{self::Class1?} null : let final self::Class1 #t111 = let final self::Class1 #t112 = let final self::Class1 #t113 = new self::Class1::•() in let final void #t114 = self::Extension1|set#nullable1(new self::Class1::•(), #t113) in #t113 in let final void #t115 = self::Extension1|set#nullable1(new self::Class1::•(), #t112) in #t112 in let final void #t116 = self::Extension1|set#nullable1(#t110{self::Class1}, #t111) in #t111;
+  let final self::Class1? #t117 = n1 in #t117 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t117{self::Class1}, let final self::Class1 #t118 = self::Extension1|nonNullable1Method(new self::Class1::•()) in let final void #t119 = self::Extension1|set#nullable1(new self::Class1::•(), #t118) in #t118);
+  nullable1 = let final self::Class1? #t120 = n1 in #t120 == null ?{self::Class1?} null : let final self::Class1 #t121 = let final self::Class1 #t122 = self::Extension1|nonNullable1Method(new self::Class1::•()) in let final void #t123 = self::Extension1|set#nullable1(new self::Class1::•(), #t122) in #t122 in let final void #t124 = self::Extension1|set#nullable1(#t120{self::Class1}, #t121) in #t121;
+  let final self::Class1? #t125 = n1 in #t125 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(#t125{self::Class1}), self::Extension1|get#nullable1(new self::Class1::•()));
+  nullable1 = let final self::Class1? #t126 = n1 in #t126 == null ?{self::Class1?} null : let final self::Class1? #t127 = self::Extension1|get#nullable1(new self::Class1::•()) in let final void #t128 = self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(#t126{self::Class1}), #t127) in #t127;
+  let final self::Class1? #t129 = n1 in #t129 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(#t129{self::Class1}), let final self::Class1 #t130 = new self::Class1::•() in let final void #t131 = self::Extension1|set#nullable1(new self::Class1::•(), #t130) in #t130);
+  nullable1 = let final self::Class1? #t132 = n1 in #t132 == null ?{self::Class1?} null : let final self::Class1 #t133 = let final self::Class1 #t134 = new self::Class1::•() in let final void #t135 = self::Extension1|set#nullable1(new self::Class1::•(), #t134) in #t134 in let final void #t136 = self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(#t132{self::Class1}), #t133) in #t133;
+  let final self::Class1? #t137 = n1 in #t137 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(#t137{self::Class1}), self::Extension1|nonNullable1Method(new self::Class1::•()));
+  nullable1 = let final self::Class1? #t138 = n1 in #t138 == null ?{self::Class1?} null : let final self::Class1 #t139 = self::Extension1|nonNullable1Method(new self::Class1::•()) in let final void #t140 = self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(#t138{self::Class1}), #t139) in #t139;
+  let final self::Class1? #t141 = n1 in #t141 == null ?{self::Class1?} null : self::Extension1|get#nullable1(self::Extension1|nonNullable1Method(self::Extension1|get#nonNullable1(#t141{self::Class1})));
+  let final self::Class1? #t142 = n1 in #t142 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(self::Extension1|get#nonNullable1(#t142{self::Class1})), new self::Class1::•());
+  nullable1 = let final self::Class1? #t143 = n1 in #t143 == null ?{self::Class1?} null : let final self::Class1 #t144 = new self::Class1::•() in let final void #t145 = self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(self::Extension1|get#nonNullable1(#t143{self::Class1})), #t144) in #t144;
+  let final self::Class1? #t146 = n1 in #t146 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(self::Extension1|get#nonNullable1(#t146{self::Class1})));
+  let final self::Class1? #t147 = n1 in #t147 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t147{self::Class1}, self::Extension1|get#nullable1(self::Extension1|nonNullable1Method(new self::Class1::•())));
+  nullable1 = let final self::Class1? #t148 = n1 in #t148 == null ?{self::Class1?} null : let final self::Class1? #t149 = self::Extension1|get#nullable1(self::Extension1|nonNullable1Method(new self::Class1::•())) in let final void #t150 = self::Extension1|set#nullable1(#t148{self::Class1}, #t149) in #t149;
+  let final self::Class1? #t151 = n1 in #t151 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t151{self::Class1}, let final self::Class1 #t152 = new self::Class1::•() in let final void #t153 = self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(new self::Class1::•()), #t152) in #t152);
+  nullable1 = let final self::Class1? #t154 = n1 in #t154 == null ?{self::Class1?} null : let final self::Class1 #t155 = let final self::Class1 #t156 = new self::Class1::•() in let final void #t157 = self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(new self::Class1::•()), #t156) in #t156 in let final void #t158 = self::Extension1|set#nullable1(#t154{self::Class1}, #t155) in #t155;
+  let final self::Class1? #t159 = n1 in #t159 == null ?{self::Class1?} null : self::Extension1|set#nullable1(#t159{self::Class1}, self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(new self::Class1::•())));
+  nullable1 = let final self::Class1? #t160 = n1 in #t160 == null ?{self::Class1?} null : let final self::Class1 #t161 = self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(new self::Class1::•())) in let final void #t162 = self::Extension1|set#nullable1(#t160{self::Class1}, #t161) in #t161;
+  let final self::Class1? #t163 = n1 in #t163 == null ?{self::Class1?} null : self::Extension1|get#nullable1(self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(#t163{self::Class1})));
+  let final self::Class1? #t164 = n1 in #t164 == null ?{self::Class1?} null : self::Extension1|set#nullable1(self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(#t164{self::Class1})), new self::Class1::•());
+  let final self::Class1? #t165 = n1 in #t165 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(self::Extension1|nonNullable1Method(#t165{self::Class1})));
+  let final self::Class1? #t166 = n1 in #t166 == null ?{self::Class1?} null : let final self::Class1? #t167 = self::Extension1|nonNullable1Method(#t166{self::Class1}) in #t167 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t167{self::Class1});
+}
+static method indexAccess(self::Class1? n1, self::Class2? n2, self::Class3? n3) → void {
+  self::Class1? nullable1 = n1;
+  self::Class2? nullable2 = n2;
+  self::Class3? nullable3 = n3;
+  let final self::Class1? #t168 = n1 in #t168 == null ?{self::Class1?} null : self::Extension1|[](#t168{self::Class1}, nullable1);
+  let final self::Class1? #t169 = n1 in #t169 == null ?{self::Class1?} null : self::Extension1|[]=(#t169{self::Class1}, nullable1, new self::Class1::•());
+  let final self::Class1? #t170 = n1 in #t170 == null ?{self::Class1?} null : let final self::Class1? #t171 = self::Extension1|[](#t170{self::Class1}, nullable1) in #t171 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t171{self::Class1});
+  let final self::Class1? #t172 = n1 in #t172 == null ?{self::Class1?} null : self::Extension1|[](self::Extension1|get#nonNullable1(#t172{self::Class1}), nullable1);
+  let final self::Class1? #t173 = n1 in #t173 == null ?{self::Class1?} null : self::Extension1|[]=(self::Extension1|get#nonNullable1(#t173{self::Class1}), nullable1, new self::Class1::•());
+  nullable1 = let final self::Class1? #t174 = n1 in #t174 == null ?{self::Class1?} null : let final self::Class1 #t175 = self::Extension1|get#nonNullable1(#t174{self::Class1}) in let final self::Class1? #t176 = nullable1 in let final self::Class1 #t177 = new self::Class1::•() in let final void #t178 = self::Extension1|[]=(#t175, #t176, #t177) in #t177;
+  let final self::Class1? #t179 = n1 in #t179 == null ?{self::Class1?} null : let final self::Class1? #t180 = self::Extension1|[](self::Extension1|get#nonNullable1(#t179{self::Class1}), nullable1) in #t180 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t180{self::Class1});
+  let final self::Class1? #t181 = n1 in #t181 == null ?{self::Class2?} null : let final self::Class2 #t182 = self::Extension1|get#nonNullable2(#t181{self::Class1}) in let final self::Class2? #t183 = nullable2 in self::Extension2|[]=(#t182, #t183, self::Extension2|+(self::Extension2|[](#t182, #t183), 0));
+  nullable2 = let final self::Class1? #t184 = n1 in #t184 == null ?{self::Class2?} null : let final self::Class2 #t185 = self::Extension1|get#nonNullable2(#t184{self::Class1}) in let final self::Class2? #t186 = nullable2 in let final self::Class2 #t187 = self::Extension2|+(self::Extension2|[](#t185, #t186), 0) in let final void #t188 = self::Extension2|[]=(#t185, #t186, #t187) in #t187;
+  let final self::Class1? #t189 = n1 in #t189 == null ?{self::Class1?} null : let final self::Class1? #t190 = nullable1 in self::Extension1|[](#t189{self::Class1}, #t190) == null ?{self::Class1?} self::Extension1|[]=(#t189{self::Class1}, #t190, nullable1) : null;
+  nullable1 = let final self::Class1? #t191 = n1 in #t191 == null ?{self::Class1?} null : let final self::Class1? #t192 = nullable1 in let final self::Class1? #t193 = self::Extension1|[](#t191{self::Class1}, #t192) in #t193 == null ?{self::Class1?} let final self::Class1? #t194 = nullable1 in let final void #t195 = self::Extension1|[]=(#t191{self::Class1}, #t192, #t194) in #t194 : #t193{self::Class1};
+  let final self::Class2? #t196 = n2 in #t196 == null ?{self::Class2?} null : let final self::Class2? #t197 = nullable2 in self::Extension2|[]=(#t196{self::Class2}, #t197, self::Extension2|+(self::Extension2|[](#t196{self::Class2}, #t197), 0));
+  nullable2 = let final self::Class2? #t198 = n2 in #t198 == null ?{self::Class2?} null : let final self::Class2? #t199 = nullable2 in let final self::Class2 #t200 = self::Extension2|+(self::Extension2|[](#t198{self::Class2}, #t199), 0) in let final void #t201 = self::Extension2|[]=(#t198{self::Class2}, #t199, #t200) in #t200;
+  let final self::Class2? #t202 = n2 in #t202 == null ?{self::Class2?} null : let final self::Class2? #t203 = nullable2 in self::Extension2|[]=(#t202{self::Class2}, #t203, self::Extension2|+(self::Extension2|[](#t202{self::Class2}, #t203), 0));
+  nullable2 = let final self::Class2? #t204 = n2 in #t204 == null ?{self::Class2?} null : let final self::Class2? #t205 = nullable2 in let final self::Class2 #t206 = self::Extension2|+(self::Extension2|[](#t204{self::Class2}, #t205), 0) in let final void #t207 = self::Extension2|[]=(#t204{self::Class2}, #t205, #t206) in #t206;
+  let final self::Class2? #t208 = n2 in #t208 == null ?{self::Class2?} null : let final self::Class2? #t209 = nullable2 in self::Extension2|[]=(#t208{self::Class2}, #t209, self::Extension2|+(self::Extension2|[](#t208{self::Class2}, #t209), 1));
+  nullable2 = let final self::Class2? #t210 = n2 in #t210 == null ?{self::Class2?} null : let final self::Class2? #t211 = nullable2 in let final self::Class2 #t212 = self::Extension2|[](#t210{self::Class2}, #t211) in let final void #t213 = self::Extension2|[]=(#t210{self::Class2}, #t211, self::Extension2|+(#t212, 1)) in #t212;
+  let final self::Class2? #t214 = n2 in #t214 == null ?{self::Class2?} null : let final self::Class2? #t215 = nullable2 in let final self::Class2 #t216 = self::Extension2|+(self::Extension2|[](#t214{self::Class2}, #t215), 1) in let final void #t217 = self::Extension2|[]=(#t214{self::Class2}, #t215, #t216) in #t216;
+  nullable2 = let final self::Class2? #t218 = n2 in #t218 == null ?{self::Class2?} null : let final self::Class2? #t219 = nullable2 in let final self::Class2 #t220 = self::Extension2|+(self::Extension2|[](#t218{self::Class2}, #t219), 1) in let final void #t221 = self::Extension2|[]=(#t218{self::Class2}, #t219, #t220) in #t220;
+  let final self::Class1? #t222 = n1 in #t222 == null ?{self::Class2?} null : let final self::Class2 #t223 = self::Extension1|get#nonNullable2(#t222{self::Class1}) in let final self::Class2? #t224 = nullable2 in self::Extension2|[]=(#t223, #t224, self::Extension2|+(self::Extension2|[](#t223, #t224), 1));
+  nullable2 = let final self::Class1? #t225 = n1 in #t225 == null ?{self::Class2?} null : let final self::Class2 #t226 = self::Extension1|get#nonNullable2(#t225{self::Class1}) in let final self::Class2? #t227 = nullable2 in let final self::Class2 #t228 = self::Extension2|[](#t226, #t227) in let final void #t229 = self::Extension2|[]=(#t226, #t227, self::Extension2|+(#t228, 1)) in #t228;
+  let final self::Class1? #t230 = n1 in #t230 == null ?{self::Class2?} null : let final self::Class2 #t231 = self::Extension1|get#nonNullable2(#t230{self::Class1}) in let final self::Class2? #t232 = nullable2 in let final self::Class2 #t233 = self::Extension2|+(self::Extension2|[](#t231, #t232), 1) in let final void #t234 = self::Extension2|[]=(#t231, #t232, #t233) in #t233;
+  nullable2 = let final self::Class1? #t235 = n1 in #t235 == null ?{self::Class2?} null : let final self::Class2 #t236 = self::Extension1|get#nonNullable2(#t235{self::Class1}) in let final self::Class2? #t237 = nullable2 in let final self::Class2 #t238 = self::Extension2|+(self::Extension2|[](#t236, #t237), 1) in let final void #t239 = self::Extension2|[]=(#t236, #t237, #t238) in #t238;
+  let final self::Class1? #t240 = n1 in #t240 == null ?{self::Class2?} null : self::Extension2|[](self::Extension2|[](self::Extension1|get#nonNullable2(#t240{self::Class1}), nullable2), nullable2);
+  let final self::Class1? #t241 = n1 in #t241 == null ?{self::Class2?} null : self::Extension2|[]=(self::Extension2|[](self::Extension1|get#nonNullable2(#t241{self::Class1}), nullable2), nullable2, new self::Class2::•());
+  nullable2 = let final self::Class1? #t242 = n1 in #t242 == null ?{self::Class2?} null : let final self::Class2 #t243 = self::Extension2|[](self::Extension1|get#nonNullable2(#t242{self::Class1}), nullable2) in let final self::Class2? #t244 = nullable2 in let final self::Class2 #t245 = new self::Class2::•() in let final void #t246 = self::Extension2|[]=(#t243, #t244, #t245) in #t245;
+  let final self::Class1? #t247 = n1 in #t247 == null ?{self::Class2?} null : let final self::Class2? #t248 = self::Extension2|[](self::Extension2|[](self::Extension1|get#nonNullable2(#t247{self::Class1}), nullable2), nullable2) in #t248 == null ?{self::Class2?} null : self::Extension2|nonNullable2Method(#t248{self::Class2});
+  let final self::Class1? #t249 = n1 in #t249 == null ?{self::Class2?} null : let final self::Class2 #t250 = self::Extension2|[](self::Extension1|get#nonNullable2(#t249{self::Class1}), nullable2) in let final self::Class2? #t251 = nullable2 in self::Extension2|[]=(#t250, #t251, self::Extension2|+(self::Extension2|[](#t250, #t251), 0));
+  nullable2 = let final self::Class1? #t252 = n1 in #t252 == null ?{self::Class2?} null : let final self::Class2 #t253 = self::Extension2|[](self::Extension1|get#nonNullable2(#t252{self::Class1}), nullable2) in let final self::Class2? #t254 = nullable2 in let final self::Class2 #t255 = self::Extension2|+(self::Extension2|[](#t253, #t254), 0) in let final void #t256 = self::Extension2|[]=(#t253, #t254, #t255) in #t255;
+  let final self::Class1? #t257 = n1 in #t257 == null ?{self::Class2?} null : let final self::Class2 #t258 = self::Extension2|[](self::Extension1|get#nonNullable2(#t257{self::Class1}), nullable2) in let final self::Class2? #t259 = nullable2 in self::Extension2|[]=(#t258, #t259, self::Extension2|+(self::Extension2|[](#t258, #t259), 1));
+  nullable2 = let final self::Class1? #t260 = n1 in #t260 == null ?{self::Class2?} null : let final self::Class2 #t261 = self::Extension2|[](self::Extension1|get#nonNullable2(#t260{self::Class1}), nullable2) in let final self::Class2? #t262 = nullable2 in let final self::Class2 #t263 = self::Extension2|[](#t261, #t262) in let final void #t264 = self::Extension2|[]=(#t261, #t262, self::Extension2|+(#t263, 1)) in #t263;
+  let final self::Class1? #t265 = n1 in #t265 == null ?{self::Class2?} null : let final self::Class2 #t266 = self::Extension2|[](self::Extension1|get#nonNullable2(#t265{self::Class1}), nullable2) in let final self::Class2? #t267 = nullable2 in let final self::Class2 #t268 = self::Extension2|+(self::Extension2|[](#t266, #t267), 1) in let final void #t269 = self::Extension2|[]=(#t266, #t267, #t268) in #t268;
+  nullable2 = let final self::Class1? #t270 = n1 in #t270 == null ?{self::Class2?} null : let final self::Class2 #t271 = self::Extension2|[](self::Extension1|get#nonNullable2(#t270{self::Class1}), nullable2) in let final self::Class2? #t272 = nullable2 in let final self::Class2 #t273 = self::Extension2|+(self::Extension2|[](#t271, #t272), 1) in let final void #t274 = self::Extension2|[]=(#t271, #t272, #t273) in #t273;
+  let final self::Class1? #t275 = n1 in #t275 == null ?{self::Class1?} null : let final self::Class1? #t276 = self::Extension1|[](#t275{self::Class1}, nullable1) in #t276 == null ?{self::Class1?} null : self::Extension1|[](#t276{self::Class1}, nullable1);
+  let final self::Class1? #t277 = n1 in #t277 == null ?{self::Class1?} null : let final self::Class1? #t278 = self::Extension1|[](#t277{self::Class1}, nullable1) in #t278 == null ?{self::Class1?} null : self::Extension1|[]=(#t278{self::Class1}, nullable1, new self::Class1::•());
+  nullable1 = let final self::Class1? #t279 = n1 in #t279 == null ?{self::Class1?} null : let final self::Class1? #t280 = self::Extension1|[](#t279{self::Class1}, nullable1) in #t280 == null ?{self::Class1?} null : let final self::Class1? #t281 = nullable1 in let final self::Class1 #t282 = new self::Class1::•() in let final void #t283 = self::Extension1|[]=(#t280{self::Class1}, #t281, #t282) in #t282;
+  let final self::Class1? #t284 = n1 in #t284 == null ?{self::Class1?} null : let final self::Class1? #t285 = self::Extension1|[](#t284{self::Class1}, nullable1) in #t285 == null ?{self::Class1?} null : let final self::Class1? #t286 = self::Extension1|[](#t285{self::Class1}, nullable1) in #t286 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t286{self::Class1});
+  nullable1 = let final self::Class1? #t287 = n1 in #t287 == null ?{self::Class1?} null : let final self::Class1? #t288 = self::Extension1|[](#t287{self::Class1}, nullable1) in #t288 == null ?{self::Class1?} null : let final self::Class1? #t289 = self::Extension1|[](#t288{self::Class1}, nullable1) in #t289 == null ?{self::Class1?} null : self::Extension1|nonNullable1Method(#t289{self::Class1});
+  let final self::Class1? #t290 = n1 in #t290 == null ?{self::Class1?} null : let final self::Class1? #t291 = self::Extension1|[](#t290{self::Class1}, nullable1) in #t291 == null ?{self::Class1?} null : let final self::Class1? #t292 = nullable1 in self::Extension1|[](#t291{self::Class1}, #t292) == null ?{self::Class1?} self::Extension1|[]=(#t291{self::Class1}, #t292, nullable1) : null;
+  nullable1 = let final self::Class1? #t293 = n1 in #t293 == null ?{self::Class1?} null : let final self::Class1? #t294 = self::Extension1|[](#t293{self::Class1}, nullable1) in #t294 == null ?{self::Class1?} null : let final self::Class1? #t295 = nullable1 in let final self::Class1? #t296 = self::Extension1|[](#t294{self::Class1}, #t295) in #t296 == null ?{self::Class1?} let final self::Class1? #t297 = nullable1 in let final void #t298 = self::Extension1|[]=(#t294{self::Class1}, #t295, #t297) in #t297 : #t296{self::Class1};
+  let final self::Class3? #t299 = n3 in #t299 == null ?{self::Class2?} null : let final self::Class2? #t300 = self::Extension3|[](#t299{self::Class3}, nullable3) in #t300 == null ?{self::Class2?} null : let final self::Class2? #t301 = nullable2 in self::Extension2|[]=(#t300{self::Class2}, #t301, self::Extension2|+(self::Extension2|[](#t300{self::Class2}, #t301), 0));
+  nullable2 = let final self::Class3? #t302 = n3 in #t302 == null ?{self::Class2?} null : let final self::Class2? #t303 = self::Extension3|[](#t302{self::Class3}, nullable3) in #t303 == null ?{self::Class2?} null : let final self::Class2? #t304 = nullable2 in let final self::Class2 #t305 = self::Extension2|+(self::Extension2|[](#t303{self::Class2}, #t304), 0) in let final void #t306 = self::Extension2|[]=(#t303{self::Class2}, #t304, #t305) in #t305;
+  let final self::Class3? #t307 = n3 in #t307 == null ?{self::Class2?} null : let final self::Class2? #t308 = self::Extension3|[](#t307{self::Class3}, nullable3) in #t308 == null ?{self::Class2?} null : let final self::Class2? #t309 = nullable2 in self::Extension2|[]=(#t308{self::Class2}, #t309, self::Extension2|+(self::Extension2|[](#t308{self::Class2}, #t309), 1));
+  nullable2 = let final self::Class3? #t310 = n3 in #t310 == null ?{self::Class2?} null : let final self::Class2? #t311 = self::Extension3|[](#t310{self::Class3}, nullable3) in #t311 == null ?{self::Class2?} null : let final self::Class2? #t312 = nullable2 in let final self::Class2 #t313 = self::Extension2|[](#t311{self::Class2}, #t312) in let final void #t314 = self::Extension2|[]=(#t311{self::Class2}, #t312, self::Extension2|+(#t313, 1)) in #t313;
+  let final self::Class3? #t315 = n3 in #t315 == null ?{self::Class2?} null : let final self::Class2? #t316 = self::Extension3|[](#t315{self::Class3}, nullable3) in #t316 == null ?{self::Class2?} null : let final self::Class2? #t317 = nullable2 in let final self::Class2 #t318 = self::Extension2|+(self::Extension2|[](#t316{self::Class2}, #t317), 1) in let final void #t319 = self::Extension2|[]=(#t316{self::Class2}, #t317, #t318) in #t318;
+  nullable2 = let final self::Class3? #t320 = n3 in #t320 == null ?{self::Class2?} null : let final self::Class2? #t321 = self::Extension3|[](#t320{self::Class3}, nullable3) in #t321 == null ?{self::Class2?} null : let final self::Class2? #t322 = nullable2 in let final self::Class2 #t323 = self::Extension2|+(self::Extension2|[](#t321{self::Class2}, #t322), 1) in let final void #t324 = self::Extension2|[]=(#t321{self::Class2}, #t322, #t323) in #t323;
+}
+static method operatorAccess(self::Class1? n1, self::Class2? n2) → void {
+  self::Class2? nullable2 = n2;
+  self::throws(() → void => invalid-expression "pkg/front_end/testcases/nnbd/null_shorting_extension.dart:226:33: Error: Operator '+' cannot be called on 'Class1?' because it is potentially null.
+ - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_extension.dart'.
+  throws(() => n1?.nonNullable1 + 0);
+                                ^" in self::Extension1|+(let final self::Class1? #t325 = n1 in #t325 == null ?{self::Class1?} null : self::Extension1|get#nonNullable1(#t325{self::Class1}), 0));
+  self::throws(() → void => invalid-expression "pkg/front_end/testcases/nnbd/null_shorting_extension.dart:227:16: Error: Operator 'unary-' cannot be called on 'Class1?' because it is potentially null.
+ - 'Class1' is from 'pkg/front_end/testcases/nnbd/null_shorting_extension.dart'.
+  throws(() => -n1?.nonNullable1);
+               ^" in self::Extension1|unary-(let final self::Class1? #t326 = n1 in #t326 == null ?{self::Class1?} null : self::Extension1|get#nonNullable1(#t326{self::Class1})));
+  let final self::Class2? #t327 = n2 in #t327 == null ?{self::Class2?} null : self::Extension2|set#nonNullable2(#t327, self::Extension2|+(self::Extension2|get#nonNullable2(#t327), 0));
+  nullable2 = let final self::Class2? #t328 = n2 in #t328 == null ?{self::Class2?} null : let final self::Class2 #t329 = self::Extension2|+(self::Extension2|get#nonNullable2(#t328), 0) in let final void #t330 = self::Extension2|set#nonNullable2(#t328, #t329) in #t329;
+  let final self::Class2? #t331 = n2 in #t331 == null ?{self::Class2?} null : let final self::Class2 #t332 = self::Extension2|get#nonNullable2(#t331{self::Class2}) in self::Extension2|set#nonNullable2(#t332, self::Extension2|+(self::Extension2|get#nonNullable2(#t332), 0));
+  nullable2 = let final self::Class2? #t333 = n2 in #t333 == null ?{self::Class2?} null : let final self::Class2 #t334 = self::Extension2|get#nonNullable2(#t333{self::Class2}) in let final self::Class2 #t335 = self::Extension2|+(self::Extension2|get#nonNullable2(#t334), 0) in let final void #t336 = self::Extension2|set#nonNullable2(#t334, #t335) in #t335;
+  let final self::Class2? #t337 = n2 in #t337 == null ?{self::Class2?} null : self::Extension2|set#nonNullable2(#t337, self::Extension2|+(self::Extension2|get#nonNullable2(#t337), 1));
+  nullable2 = let final self::Class2? #t338 = n2 in #t338 == null ?{self::Class2?} null : let final self::Class2 #t339 = self::Extension2|get#nonNullable2(#t338) in let final void #t340 = self::Extension2|set#nonNullable2(#t338, self::Extension2|+(#t339, 1)) in #t339;
+  let final self::Class2? #t341 = n2 in #t341 == null ?{self::Class2?} null : let final self::Class2 #t342 = self::Extension2|+(self::Extension2|get#nonNullable2(#t341), 1) in let final void #t343 = self::Extension2|set#nonNullable2(#t341, #t342) in #t342;
+  nullable2 = let final self::Class2? #t344 = n2 in #t344 == null ?{self::Class2?} null : let final self::Class2 #t345 = self::Extension2|+(self::Extension2|get#nonNullable2(#t344), 1) in let final void #t346 = self::Extension2|set#nonNullable2(#t344, #t345) in #t345;
+}
+static method ifNull(self::Class1? n1) → void {
+  self::Class1? nullable1 = n1;
+  let final self::Class1? #t347 = n1 in #t347 == null ?{self::Class1?} null : self::Extension1|get#nullable1(#t347) == null ?{self::Class1} self::Extension1|set#nullable1(#t347, n1{self::Class1}) : null;
+  n1 = let final self::Class1? #t348 = n1 in #t348 == null ?{self::Class1?} null : let final self::Class1? #t349 = self::Extension1|get#nullable1(#t348) in #t349 == null ?{self::Class1} let final self::Class1 #t350 = n1{self::Class1} in let final void #t351 = self::Extension1|set#nullable1(#t348, #t350) in #t350 : #t349{self::Class1};
+  let final self::Class1? #t352 = n1 in #t352 == null ?{self::Class1?} null : let final self::Class1 #t353 = self::Extension1|get#nonNullable1(#t352{self::Class1}) in self::Extension1|get#nullable1(#t353) == null ?{self::Class1} self::Extension1|set#nullable1(#t353, n1{self::Class1}) : null;
+  n1 = let final self::Class1? #t354 = n1 in #t354 == null ?{self::Class1?} null : let final self::Class1 #t355 = self::Extension1|get#nonNullable1(#t354{self::Class1}) in let final self::Class1? #t356 = self::Extension1|get#nullable1(#t355) in #t356 == null ?{self::Class1} let final self::Class1 #t357 = n1{self::Class1} in let final void #t358 = self::Extension1|set#nullable1(#t355, #t357) in #t357 : #t356{self::Class1};
+  let final self::Class1? #t359 = n1 in #t359 == null ?{self::Class1?} null : let final self::Class1 #t360 = self::Extension1|get#nonNullable1(#t359{self::Class1}) in let final self::Class1 #t361 = n1{self::Class1} in self::Extension1|[](#t360, #t361) == null ?{self::Class1} self::Extension1|[]=(#t360, #t361, n1{self::Class1}) : null;
+  n1 = let final self::Class1? #t362 = n1 in #t362 == null ?{self::Class1?} null : let final self::Class1 #t363 = self::Extension1|get#nonNullable1(#t362{self::Class1}) in let final self::Class1 #t364 = n1{self::Class1} in let final self::Class1? #t365 = self::Extension1|[](#t363, #t364) in #t365 == null ?{self::Class1} let final self::Class1 #t366 = n1{self::Class1} in let final void #t367 = self::Extension1|[]=(#t363, #t364, #t366) in #t366 : #t365{self::Class1};
+}
+static method throws(() → void f) → void {
+  try {
+    f(){() → void};
+  }
+  on core::Object catch(final core::Object _) {
+    return;
+  }
+  throw "Expected exception.";
+}
diff --git a/pkg/front_end/testcases/nnbd/null_shorting_index.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/null_shorting_index.dart.weak.modular.expect
new file mode 100644
index 0000000..438791b
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/null_shorting_index.dart.weak.modular.expect
@@ -0,0 +1,133 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/null_shorting_index.dart:31:6: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   c1?[0] ??= 1;
+//      ^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_index.dart:32:6: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   c1?[0] ??= 1 + c1[1];
+//      ^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_index.dart:42:6: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   c2?[0] ??= 1;
+//      ^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_index.dart:43:6: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   c2?[0] ??= 1 + c2[1];
+//      ^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_index.dart:52:17: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   Extension(c2)?[0] ??= 1;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_index.dart:53:17: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   Extension(c2)?[0] ??= 1 + Extension(c2)[1];
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_index.dart:62:13: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   c1?.field?[0] ??= 1;
+//             ^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_index.dart:63:13: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   c1?.field?[0] ??= 1 + c1[1];
+//             ^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_index.dart:67:49: Warning: Operand of null-aware operation '!' has type 'int' which excludes null.
+//   Extension(c1?.field)?[0] = 1 + (Extension(c2)?[0]! as int);
+//                                                 ^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_index.dart:69:50: Warning: Operand of null-aware operation '!' has type 'int' which excludes null.
+//   Extension(c1?.field)?[0] += 1 + (Extension(c2)?[0]! as int);
+//                                                  ^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_index.dart:72:24: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   Extension(c1?.field)?[0] ??= 1;
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_index.dart:73:24: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   Extension(c1?.field)?[0] ??= 1 + (Extension(c2)?[1]! as int);
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/null_shorting_index.dart:73:51: Warning: Operand of null-aware operation '!' has type 'int' which excludes null.
+//   Extension(c1?.field)?[0] ??= 1 + (Extension(c2)?[1]! as int);
+//                                                   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+  get field() → self::Class2?
+    return null;
+  operator [](core::int index) → core::int
+    return index;
+  operator []=(core::int index, core::int value) → void {}
+}
+class Class2 extends core::Object {
+  field core::int field = 42;
+  synthetic constructor •() → self::Class2
+    : super core::Object::•()
+    ;
+}
+extension Extension on self::Class2 {
+  operator [] = self::Extension|[];
+  operator []= = self::Extension|[]=;
+}
+static method Extension|[](lowered final self::Class2 #this, core::int index) → core::int
+  return #this.{self::Class2::field}{core::int};
+static method Extension|[]=(lowered final self::Class2 #this, core::int index, core::int value) → void {
+  #this.{self::Class2::field} = value;
+}
+static method main() → dynamic {
+  self::Class1? c1;
+  let final self::Class1? #t1 = c1 in #t1 == null ?{core::int?} null : #t1{self::Class1}.{self::Class1::[]}(0){(core::int) → core::int};
+  let final self::Class1? #t2 = c1 in #t2 == null ?{core::int?} null : #t2{self::Class1}.{self::Class1::[]=}(0, 1){(core::int, core::int) → void};
+  let final self::Class1? #t3 = c1 in #t3 == null ?{core::int?} null : #t3{self::Class1}.{self::Class1::[]=}(0, 1.{core::num::+}(c1{self::Class1}.{self::Class1::[]}(0){(core::int) → core::int}){(core::num) → core::int}){(core::int, core::int) → void};
+  let final self::Class1? #t4 = c1 in #t4 == null ?{core::int?} null : let final core::int #t5 = 0 in #t4{self::Class1}.{self::Class1::[]=}(#t5, #t4{self::Class1}.{self::Class1::[]}(#t5){(core::int) → core::int}.{core::num::+}(1){(core::num) → core::int}){(core::int, core::int) → void};
+  let final self::Class1? #t6 = c1 in #t6 == null ?{core::int?} null : let final core::int #t7 = 0 in #t6{self::Class1}.{self::Class1::[]=}(#t7, #t6{self::Class1}.{self::Class1::[]}(#t7){(core::int) → core::int}.{core::num::+}(1.{core::num::+}(c1{self::Class1}.{self::Class1::[]}(0){(core::int) → core::int}){(core::num) → core::int}){(core::num) → core::int}){(core::int, core::int) → void};
+  let final self::Class1? #t8 = c1 in #t8 == null ?{core::int?} null : let final core::int #t9 = 0 in let final core::int #t10 = #t8{self::Class1}.{self::Class1::[]}(#t9){(core::int) → core::int}.{core::num::+}(1){(core::num) → core::int} in let final void #t11 = #t8{self::Class1}.{self::Class1::[]=}(#t9, #t10){(core::int, core::int) → void} in #t10;
+  let final self::Class1? #t12 = c1 in #t12 == null ?{core::int?} null : let final core::int #t13 = 0 in #t12{self::Class1}.{self::Class1::[]=}(#t13, #t12{self::Class1}.{self::Class1::[]}(#t13){(core::int) → core::int}.{core::num::+}(1){(core::num) → core::int}){(core::int, core::int) → void};
+  let final self::Class1? #t14 = c1 in #t14 == null ?{core::int?} null : let final core::int #t15 = 0 in #t14{self::Class1}.{self::Class1::[]}(#t15){(core::int) → core::int} == null ?{core::int} #t14{self::Class1}.{self::Class1::[]=}(#t15, 1){(core::int, core::int) → void} : null;
+  let final self::Class1? #t16 = c1 in #t16 == null ?{core::int?} null : let final core::int #t17 = 0 in #t16{self::Class1}.{self::Class1::[]}(#t17){(core::int) → core::int} == null ?{core::int} #t16{self::Class1}.{self::Class1::[]=}(#t17, 1.{core::num::+}(c1{self::Class1}.{self::Class1::[]}(1){(core::int) → core::int}){(core::num) → core::int}){(core::int, core::int) → void} : null;
+  self::Class2? c2;
+  let final self::Class2? #t18 = c2 in #t18 == null ?{core::int?} null : self::Extension|[](#t18{self::Class2}, 0);
+  let final self::Class2? #t19 = c2 in #t19 == null ?{core::int?} null : self::Extension|[]=(#t19{self::Class2}, 0, 1);
+  let final self::Class2? #t20 = c2 in #t20 == null ?{core::int?} null : self::Extension|[]=(#t20{self::Class2}, 0, 1.{core::num::+}(self::Extension|[](c2{self::Class2}, 0)){(core::num) → core::int});
+  let final self::Class2? #t21 = c2 in #t21 == null ?{core::int?} null : let final core::int #t22 = 0 in self::Extension|[]=(#t21{self::Class2}, #t22, self::Extension|[](#t21{self::Class2}, #t22).{core::num::+}(1){(core::num) → core::int});
+  let final self::Class2? #t23 = c2 in #t23 == null ?{core::int?} null : let final core::int #t24 = 0 in self::Extension|[]=(#t23{self::Class2}, #t24, self::Extension|[](#t23{self::Class2}, #t24).{core::num::+}(1.{core::num::+}(self::Extension|[](c2{self::Class2}, 0)){(core::num) → core::int}){(core::num) → core::int});
+  let final self::Class2? #t25 = c2 in #t25 == null ?{core::int?} null : let final core::int #t26 = 0 in let final core::int #t27 = self::Extension|[](#t25{self::Class2}, #t26).{core::num::+}(1){(core::num) → core::int} in let final void #t28 = self::Extension|[]=(#t25{self::Class2}, #t26, #t27) in #t27;
+  let final self::Class2? #t29 = c2 in #t29 == null ?{core::int?} null : let final core::int #t30 = 0 in self::Extension|[]=(#t29{self::Class2}, #t30, self::Extension|[](#t29{self::Class2}, #t30).{core::num::+}(1){(core::num) → core::int});
+  let final self::Class2? #t31 = c2 in #t31 == null ?{core::int?} null : let final core::int #t32 = 0 in self::Extension|[](#t31{self::Class2}, #t32) == null ?{core::int} self::Extension|[]=(#t31{self::Class2}, #t32, 1) : null;
+  let final self::Class2? #t33 = c2 in #t33 == null ?{core::int?} null : let final core::int #t34 = 0 in self::Extension|[](#t33{self::Class2}, #t34) == null ?{core::int} self::Extension|[]=(#t33{self::Class2}, #t34, 1.{core::num::+}(self::Extension|[](c2{self::Class2}, 1)){(core::num) → core::int}) : null;
+  let final self::Class2? #t35 = c2 in #t35 == null ?{core::int?} null : self::Extension|[](#t35{self::Class2}, 0);
+  let final self::Class2? #t36 = c2 in #t36 == null ?{void} null : self::Extension|[]=(#t36{self::Class2}, 0, 1);
+  let final self::Class2? #t37 = c2 in #t37 == null ?{void} null : self::Extension|[]=(#t37{self::Class2}, 0, 1.{core::num::+}(self::Extension|[](c2{self::Class2}, 0)){(core::num) → core::int});
+  let final self::Class2? #t38 = c2 in #t38 == null ?{core::int?} null : let final core::int #t39 = 0 in self::Extension|[]=(#t38{self::Class2}, #t39, self::Extension|[](#t38{self::Class2}, #t39).{core::num::+}(1){(core::num) → core::int});
+  let final self::Class2? #t40 = c2 in #t40 == null ?{core::int?} null : let final core::int #t41 = 0 in self::Extension|[]=(#t40{self::Class2}, #t41, self::Extension|[](#t40{self::Class2}, #t41).{core::num::+}(1.{core::num::+}(self::Extension|[](c2{self::Class2}, 0)){(core::num) → core::int}){(core::num) → core::int});
+  let final self::Class2? #t42 = c2 in #t42 == null ?{core::int?} null : let final core::int #t43 = 0 in let final core::int #t44 = self::Extension|[](#t42{self::Class2}, #t43).{core::num::+}(1){(core::num) → core::int} in let final void #t45 = self::Extension|[]=(#t42{self::Class2}, #t43, #t44) in #t44;
+  let final self::Class2? #t46 = c2 in #t46 == null ?{core::int?} null : let final core::int #t47 = 0 in self::Extension|[]=(#t46{self::Class2}, #t47, self::Extension|[](#t46{self::Class2}, #t47).{core::num::+}(1){(core::num) → core::int});
+  let final self::Class2? #t48 = c2 in #t48 == null ?{core::int?} null : let final core::int #t49 = 0 in self::Extension|[](#t48{self::Class2}, #t49) == null ?{core::int} self::Extension|[]=(#t48{self::Class2}, #t49, 1) : null;
+  let final self::Class2? #t50 = c2 in #t50 == null ?{core::int?} null : let final core::int #t51 = 0 in self::Extension|[](#t50{self::Class2}, #t51) == null ?{core::int} self::Extension|[]=(#t50{self::Class2}, #t51, 1.{core::num::+}(self::Extension|[](c2{self::Class2}, 1)){(core::num) → core::int}) : null;
+  let final self::Class1? #t52 = c1 in #t52 == null ?{core::int?} null : let final self::Class2? #t53 = #t52{self::Class1}.{self::Class1::field}{self::Class2?} in #t53 == null ?{core::int?} null : self::Extension|[](#t53{self::Class2}, 0);
+  let final self::Class1? #t54 = c1 in #t54 == null ?{core::int?} null : let final self::Class2? #t55 = #t54{self::Class1}.{self::Class1::field}{self::Class2?} in #t55 == null ?{core::int?} null : self::Extension|[]=(#t55{self::Class2}, 0, 1);
+  let final self::Class1? #t56 = c1 in #t56 == null ?{core::int?} null : let final self::Class2? #t57 = #t56{self::Class1}.{self::Class1::field}{self::Class2?} in #t57 == null ?{core::int?} null : self::Extension|[]=(#t57{self::Class2}, 0, 1.{core::num::+}(c1{self::Class1}.{self::Class1::[]}(0){(core::int) → core::int}){(core::num) → core::int});
+  let final self::Class1? #t58 = c1 in #t58 == null ?{core::int?} null : let final self::Class2? #t59 = #t58{self::Class1}.{self::Class1::field}{self::Class2?} in #t59 == null ?{core::int?} null : let final core::int #t60 = 0 in self::Extension|[]=(#t59{self::Class2}, #t60, self::Extension|[](#t59{self::Class2}, #t60).{core::num::+}(1){(core::num) → core::int});
+  let final self::Class1? #t61 = c1 in #t61 == null ?{core::int?} null : let final self::Class2? #t62 = #t61{self::Class1}.{self::Class1::field}{self::Class2?} in #t62 == null ?{core::int?} null : let final core::int #t63 = 0 in self::Extension|[]=(#t62{self::Class2}, #t63, self::Extension|[](#t62{self::Class2}, #t63).{core::num::+}(1.{core::num::+}(c1{self::Class1}.{self::Class1::[]}(0){(core::int) → core::int}){(core::num) → core::int}){(core::num) → core::int});
+  let final self::Class1? #t64 = c1 in #t64 == null ?{core::int?} null : let final self::Class2? #t65 = #t64{self::Class1}.{self::Class1::field}{self::Class2?} in #t65 == null ?{core::int?} null : let final core::int #t66 = 0 in let final core::int #t67 = self::Extension|[](#t65{self::Class2}, #t66).{core::num::+}(1){(core::num) → core::int} in let final void #t68 = self::Extension|[]=(#t65{self::Class2}, #t66, #t67) in #t67;
+  let final self::Class1? #t69 = c1 in #t69 == null ?{core::int?} null : let final self::Class2? #t70 = #t69{self::Class1}.{self::Class1::field}{self::Class2?} in #t70 == null ?{core::int?} null : let final core::int #t71 = 0 in self::Extension|[]=(#t70{self::Class2}, #t71, self::Extension|[](#t70{self::Class2}, #t71).{core::num::+}(1){(core::num) → core::int});
+  let final self::Class1? #t72 = c1 in #t72 == null ?{core::int?} null : let final self::Class2? #t73 = #t72{self::Class1}.{self::Class1::field}{self::Class2?} in #t73 == null ?{core::int?} null : let final core::int #t74 = 0 in self::Extension|[](#t73{self::Class2}, #t74) == null ?{core::int} self::Extension|[]=(#t73{self::Class2}, #t74, 1) : null;
+  let final self::Class1? #t75 = c1 in #t75 == null ?{core::int?} null : let final self::Class2? #t76 = #t75{self::Class1}.{self::Class1::field}{self::Class2?} in #t76 == null ?{core::int?} null : let final core::int #t77 = 0 in self::Extension|[](#t76{self::Class2}, #t77) == null ?{core::int} self::Extension|[]=(#t76{self::Class2}, #t77, 1.{core::num::+}(c1{self::Class1}.{self::Class1::[]}(1){(core::int) → core::int}){(core::num) → core::int}) : null;
+  let final self::Class1? #t78 = c1 in #t78 == null ?{core::int?} null : let final self::Class2? #t79 = #t78{self::Class1}.{self::Class1::field}{self::Class2?} in #t79 == null ?{core::int?} null : self::Extension|[](#t79{self::Class2}, 0);
+  let final self::Class1? #t80 = c1 in #t80 == null ?{void} null : let final self::Class2? #t81 = #t80{self::Class1}.{self::Class1::field}{self::Class2?} in #t81 == null ?{void} null : self::Extension|[]=(#t81{self::Class2}, 0, 1);
+  let final self::Class1? #t82 = c1 in #t82 == null ?{void} null : let final self::Class2? #t83 = #t82{self::Class1}.{self::Class1::field}{self::Class2?} in #t83 == null ?{void} null : self::Extension|[]=(#t83{self::Class2}, 0, 1.{core::num::+}((let final self::Class2? #t84 = c2 in #t84 == null ?{core::int?} null : self::Extension|[](#t84{self::Class2}, 0)!) as{ForNonNullableByDefault} core::int){(core::num) → core::int});
+  let final self::Class1? #t85 = c1 in #t85 == null ?{core::int?} null : let final self::Class2? #t86 = #t85{self::Class1}.{self::Class1::field}{self::Class2?} in #t86 == null ?{core::int?} null : let final core::int #t87 = 0 in self::Extension|[]=(#t86{self::Class2}, #t87, self::Extension|[](#t86{self::Class2}, #t87).{core::num::+}(1){(core::num) → core::int});
+  let final self::Class1? #t88 = c1 in #t88 == null ?{core::int?} null : let final self::Class2? #t89 = #t88{self::Class1}.{self::Class1::field}{self::Class2?} in #t89 == null ?{core::int?} null : let final core::int #t90 = 0 in self::Extension|[]=(#t89{self::Class2}, #t90, self::Extension|[](#t89{self::Class2}, #t90).{core::num::+}(1.{core::num::+}((let final self::Class2? #t91 = c2 in #t91 == null ?{core::int?} null : self::Extension|[](#t91{self::Class2}, 0)!) as{ForNonNullableByDefault} core::int){(core::num) → core::int}){(core::num) → core::int});
+  let final self::Class1? #t92 = c1 in #t92 == null ?{core::int?} null : let final self::Class2? #t93 = #t92{self::Class1}.{self::Class1::field}{self::Class2?} in #t93 == null ?{core::int?} null : let final core::int #t94 = 0 in let final core::int #t95 = self::Extension|[](#t93{self::Class2}, #t94).{core::num::+}(1){(core::num) → core::int} in let final void #t96 = self::Extension|[]=(#t93{self::Class2}, #t94, #t95) in #t95;
+  let final self::Class1? #t97 = c1 in #t97 == null ?{core::int?} null : let final self::Class2? #t98 = #t97{self::Class1}.{self::Class1::field}{self::Class2?} in #t98 == null ?{core::int?} null : let final core::int #t99 = 0 in self::Extension|[]=(#t98{self::Class2}, #t99, self::Extension|[](#t98{self::Class2}, #t99).{core::num::+}(1){(core::num) → core::int});
+  let final self::Class1? #t100 = c1 in #t100 == null ?{core::int?} null : let final self::Class2? #t101 = #t100{self::Class1}.{self::Class1::field}{self::Class2?} in #t101 == null ?{core::int?} null : let final core::int #t102 = 0 in self::Extension|[](#t101{self::Class2}, #t102) == null ?{core::int} self::Extension|[]=(#t101{self::Class2}, #t102, 1) : null;
+  let final self::Class1? #t103 = c1 in #t103 == null ?{core::int?} null : let final self::Class2? #t104 = #t103{self::Class1}.{self::Class1::field}{self::Class2?} in #t104 == null ?{core::int?} null : let final core::int #t105 = 0 in self::Extension|[](#t104{self::Class2}, #t105) == null ?{core::int} self::Extension|[]=(#t104{self::Class2}, #t105, 1.{core::num::+}((let final self::Class2? #t106 = c2 in #t106 == null ?{core::int?} null : self::Extension|[](#t106{self::Class2}, 1)!) as{ForNonNullableByDefault} core::int){(core::num) → core::int}) : null;
+}
diff --git a/pkg/front_end/testcases/nnbd/nullable_access.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/nullable_access.dart.weak.modular.expect
new file mode 100644
index 0000000..c5958c2
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/nullable_access.dart.weak.modular.expect
@@ -0,0 +1,66 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/nullable_access.dart:23:18: Error: Property 'nonNullableField' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/nullable_access.dart'.
+// Try accessing using ?. instead.
+//   throws(() => c.nonNullableField);
+//                  ^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field self::A nonNullableField = #C1;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  get nonNullableProperty() → self::A
+    return this.{self::Class::nonNullableField}{self::A};
+  set nonNullableProperty(self::A value) → void {
+    this.{self::Class::nonNullableField} = value;
+  }
+  method nonNullableMethod() → self::A
+    return this.{self::Class::nonNullableField}{self::A};
+}
+class A extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::A
+    : super core::Object::•()
+    ;
+  get nonNullableProperty() → self::A
+    return this;
+}
+static method main() → dynamic {
+  self::Class? c;
+  self::throws(() → void => invalid-expression "pkg/front_end/testcases/nnbd/nullable_access.dart:23:18: Error: Property 'nonNullableField' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/nullable_access.dart'.
+Try accessing using ?. instead.
+  throws(() => c.nonNullableField);
+                 ^^^^^^^^^^^^^^^^" in c.{self::Class::nonNullableField}{<nullable>}.{self::A});
+  self::expect(null, let final self::Class? #t1 = c in #t1 == null ?{self::A?} null : #t1{self::Class}.{self::Class::nonNullableField}{self::A});
+  self::expect(null, let final self::Class? #t2 = c in #t2 == null ?{self::A?} null : #t2{self::Class}.{self::Class::nonNullableField}{self::A}.{self::A::nonNullableProperty}{self::A});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → void f) → dynamic {
+  try {
+    f(){() → void};
+  }
+  on core::Object catch(final core::Object e) {
+    return;
+  }
+  throw "Expected throws.";
+}
+
+constants  {
+  #C1 = self::A {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///nullable_access.dart:
+- A. (from org-dartlang-testcase:///nullable_access.dart:16:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/nullable_extension.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/nullable_extension.dart.weak.modular.expect
new file mode 100644
index 0000000..62d3a21
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/nullable_extension.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::String text = "";
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+extension _extension#0 on self::A? {
+  get text = self::_extension#0|get#text;
+}
+static method _extension#0|get#text(lowered final self::A? #this) → core::String
+  return "Lily was here";
+static method main() → void {
+  self::A? a = null;
+  self::expect("Lily was here", self::_extension#0|get#text(a));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/nnbd/nullable_null.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/nullable_null.dart.weak.modular.expect
new file mode 100644
index 0000000..82c9494
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/nullable_null.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+}
+class B extends self::A<Null> {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  method foo(Null n, self::A<Null> an) → Null
+    return n;
+}
+static method foo() → dynamic {
+  return <core::List<self::A<Null>?>>[<Null>[], <self::A<Null>>[]];
+}
+static method bar() → dynamic {
+  return <core::List<self::A<Null>?>>[#C1, #C2];
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = <Null>[]
+  #C2 = <self::A<Null>*>[]
+}
diff --git a/pkg/front_end/testcases/nnbd/nullable_object_access.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/nullable_object_access.dart.weak.modular.expect
new file mode 100644
index 0000000..3595f53
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/nullable_object_access.dart.weak.modular.expect
@@ -0,0 +1,127 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/nullable_object_access.dart:31:43: Error: The argument type 'Invocation' can't be assigned to the parameter type 'CustomInvocation'.
+//  - 'Invocation' is from 'dart:core'.
+//  - 'CustomInvocation' is from 'pkg/front_end/testcases/nnbd/nullable_object_access.dart'.
+//   String noSuchMethod1b = c1.noSuchMethod(invocation); // error
+//                                           ^
+//
+// pkg/front_end/testcases/nnbd/nullable_object_access.dart:34:9: Error: The argument type 'String' can't be assigned to the parameter type 'Class?'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/nullable_object_access.dart'.
+//   c1 == ''; // error
+//         ^
+//
+// pkg/front_end/testcases/nnbd/nullable_object_access.dart:42:32: Error: A value of type 'Type' can't be assigned to a variable of type 'CustomType'.
+//  - 'Type' is from 'dart:core'.
+//  - 'CustomType' is from 'pkg/front_end/testcases/nnbd/nullable_object_access.dart'.
+//   CustomType runtimeType2 = c2.runtimeType; // error
+//                                ^
+//
+// pkg/front_end/testcases/nnbd/nullable_object_access.dart:44:17: Error: 'runtimeType' isn't a function or method and can't be invoked.
+//   c2.runtimeType(); // error
+//                 ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/nullable_object_access.dart:47:10: Error: A value of type 'dynamic Function(Invocation)' can't be assigned to a variable of type 'String Function(CustomInvocation)'.
+//  - 'Invocation' is from 'dart:core'.
+//  - 'CustomInvocation' is from 'pkg/front_end/testcases/nnbd/nullable_object_access.dart'.
+//       c2.noSuchMethod; // error
+//          ^
+//
+// pkg/front_end/testcases/nnbd/nullable_object_access.dart:56:9: Error: The argument type 'String' can't be assigned to the parameter type 'Class?'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/nullable_object_access.dart'.
+//   c2 == ''; // ok or error?
+//         ^
+//
+// pkg/front_end/testcases/nnbd/nullable_object_access.dart:59:53: Error: A value of type 'String Function()' can't be assigned to a variable of type 'String Function({Object o})'.
+//  - 'Object' is from 'dart:core'.
+//   String Function({Object o}) toStringTearOff2 = c2.toString; // error
+//                                                     ^
+//
+// pkg/front_end/testcases/nnbd/nullable_object_access.dart:62:15: Error: No named parameter with the name 'o'.
+//   c2.toString(o: c1); // error
+//               ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class CustomType extends core::Type {
+  synthetic constructor •() → self::CustomType
+    : super core::Type::•()
+    ;
+  method call() → void {}
+}
+abstract class CustomInvocation extends core::Object implements core::Invocation {
+  synthetic constructor •() → self::CustomInvocation
+    : super core::Object::•()
+    ;
+}
+abstract class Class extends core::Object {
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  abstract get runtimeType() → self::CustomType;
+  forwarding-stub forwarding-semi-stub method /* signature-type: (self::CustomInvocation) → core::String */ noSuchMethod(covariant-by-declaration core::Invocation invocation) → core::String
+    return super.{core::Object::noSuchMethod}(invocation);
+  forwarding-stub forwarding-semi-stub operator /* signature-type: (self::Class) → core::bool */ ==(covariant-by-declaration core::Object o) → core::bool
+    return super.{core::Object::==}(o);
+  abstract method toString({core::Object o = #C1}) → core::String;
+}
+static method main() → dynamic {}
+static method test(self::Class c1, self::Class? c2, core::Invocation invocation, self::CustomInvocation customInvocation) → void {
+  self::CustomType runtimeType1 = c1.{self::Class::runtimeType}{self::CustomType};
+  self::CustomType runtimeTypeVariable1 = c1.{self::Class::runtimeType}{self::CustomType};
+  c1.{self::Class::runtimeType}{self::CustomType}.{self::CustomType::call}(){() → void};
+  (self::CustomInvocation) → core::String noSuchMethodTearOff1 = c1.{self::Class::noSuchMethod}{(self::CustomInvocation) → core::String};
+  (self::CustomInvocation) → core::String noSuchMethodTearOffVariable1 = c1.{self::Class::noSuchMethod}{(self::CustomInvocation) → core::String};
+  core::String noSuchMethod1a = c1.{self::Class::noSuchMethod}(customInvocation){(self::CustomInvocation) → core::String};
+  core::String noSuchMethod1b = c1.{self::Class::noSuchMethod}(invalid-expression "pkg/front_end/testcases/nnbd/nullable_object_access.dart:31:43: Error: The argument type 'Invocation' can't be assigned to the parameter type 'CustomInvocation'.
+ - 'Invocation' is from 'dart:core'.
+ - 'CustomInvocation' is from 'pkg/front_end/testcases/nnbd/nullable_object_access.dart'.
+  String noSuchMethod1b = c1.noSuchMethod(invocation); // error
+                                          ^" in invocation as{TypeError,ForNonNullableByDefault} self::CustomInvocation){(self::CustomInvocation) → core::String};
+  core::String noSuchMethodVariable1 = c1.{self::Class::noSuchMethod}(customInvocation){(self::CustomInvocation) → core::String};
+  c1 =={self::Class::==}{(self::Class) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/nullable_object_access.dart:34:9: Error: The argument type 'String' can't be assigned to the parameter type 'Class?'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/nullable_object_access.dart'.
+  c1 == ''; // error
+        ^" in "" as{TypeError,ForNonNullableByDefault} self::Class?;
+  c1 =={self::Class::==}{(self::Class) → core::bool} c2;
+  ({o: core::Object}) → core::String toStringTearOff1 = c1.{self::Class::toString}{({o: core::Object}) → core::String};
+  ({o: core::Object}) → core::String toStringTearOffVariable1 = c1.{self::Class::toString}{({o: core::Object}) → core::String};
+  c1.{self::Class::toString}(o: c1){({o: core::Object}) → core::String};
+  self::CustomType runtimeType2 = invalid-expression "pkg/front_end/testcases/nnbd/nullable_object_access.dart:42:32: Error: A value of type 'Type' can't be assigned to a variable of type 'CustomType'.
+ - 'Type' is from 'dart:core'.
+ - 'CustomType' is from 'pkg/front_end/testcases/nnbd/nullable_object_access.dart'.
+  CustomType runtimeType2 = c2.runtimeType; // error
+                               ^" in c2.{core::Object::runtimeType}{core::Type} as{TypeError,ForNonNullableByDefault} self::CustomType;
+  core::Type runtimeTypeVariable2 = c2.{core::Object::runtimeType}{core::Type};
+  invalid-expression "pkg/front_end/testcases/nnbd/nullable_object_access.dart:44:17: Error: 'runtimeType' isn't a function or method and can't be invoked.
+  c2.runtimeType(); // error
+                ^^^^^^^^^^^" in c2.{core::Object::runtimeType}{core::Type}{<unresolved>}.call();
+  (self::CustomInvocation) → core::String noSuchMethodTearOff2 = invalid-expression "pkg/front_end/testcases/nnbd/nullable_object_access.dart:47:10: Error: A value of type 'dynamic Function(Invocation)' can't be assigned to a variable of type 'String Function(CustomInvocation)'.
+ - 'Invocation' is from 'dart:core'.
+ - 'CustomInvocation' is from 'pkg/front_end/testcases/nnbd/nullable_object_access.dart'.
+      c2.noSuchMethod; // error
+         ^" in c2.{core::Object::noSuchMethod}{(core::Invocation) → dynamic} as{TypeError,ForNonNullableByDefault} (self::CustomInvocation) → core::String;
+  (core::Invocation) → dynamic noSuchMethodTearOffVariable2 = c2.{core::Object::noSuchMethod}{(core::Invocation) → dynamic};
+  core::int noSuchMethod2 = c2.{core::Object::noSuchMethod}(invocation){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  dynamic noSuchMethodVariable2 = c2.{core::Object::noSuchMethod}(invocation){(core::Invocation) → dynamic};
+  c2 =={self::Class::==}{(self::Class) → core::bool} invalid-expression "pkg/front_end/testcases/nnbd/nullable_object_access.dart:56:9: Error: The argument type 'String' can't be assigned to the parameter type 'Class?'.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/nullable_object_access.dart'.
+  c2 == ''; // ok or error?
+        ^" in "" as{TypeError,ForNonNullableByDefault} self::Class?;
+  c2 =={self::Class::==}{(self::Class) → core::bool} c1;
+  ({o: core::Object}) → core::String toStringTearOff2 = invalid-expression "pkg/front_end/testcases/nnbd/nullable_object_access.dart:59:53: Error: A value of type 'String Function()' can't be assigned to a variable of type 'String Function({Object o})'.
+ - 'Object' is from 'dart:core'.
+  String Function({Object o}) toStringTearOff2 = c2.toString; // error
+                                                    ^" in c2.{core::Object::toString}{() → core::String} as{TypeError,ForNonNullableByDefault} ({o: core::Object}) → core::String;
+  () → core::String toStringTearOffVariable2 = c2.{core::Object::toString}{() → core::String};
+  invalid-expression "pkg/front_end/testcases/nnbd/nullable_object_access.dart:62:15: Error: No named parameter with the name 'o'.
+  c2.toString(o: c1); // error
+              ^" in c2.{core::Object::toString}{<inapplicable>}.(o: c1){({o: invalid-type}) → invalid-type};
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/nullable_param.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/nullable_param.dart.weak.modular.expect
new file mode 100644
index 0000000..1d7f270
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/nullable_param.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  field core::int? field = null;
+  synthetic constructor •() → self::Foo
+    : super core::Object::•()
+    ;
+  method bar(core::int? x) → core::int? {}
+}
+static method main() → dynamic {
+  self::Foo foo = new self::Foo::•();
+  foo.{self::Foo::field} = 5;
+  foo.{self::Foo::bar}(6){(core::int?) → core::int?};
+  self::test_nullable_function_type_formal_param(f: () → core::int => 2);
+}
+static method test_nullable_function_type_formal_param({() →? core::int f = #C1}) → core::int {
+  return let final core::int? #t1 = let final () →? core::int #t2 = f in #t2 == null ?{core::int?} null : #t2{() → core::int}(){() → core::int} in #t1 == null ?{core::int} 1.{core::int::unary-}(){() → core::int} : #t1{core::int};
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/nullable_receiver.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/nullable_receiver.dart.weak.modular.expect
new file mode 100644
index 0000000..7274ffb
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/nullable_receiver.dart.weak.modular.expect
@@ -0,0 +1,161 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/nullable_receiver.dart:20:5: Error: Property 'length' cannot be accessed on 'String?' because it is potentially null.
+// Try accessing using ?. instead.
+//   s.length;
+//     ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/nullable_receiver.dart:21:5: Error: Method 'substring' cannot be called on 'String?' because it is potentially null.
+// Try calling using ?. instead.
+//   s.substring(1, 1);
+//     ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/nullable_receiver.dart:23:5: Error: Method 'foo' cannot be called on 'A?' because it is potentially null.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/nullable_receiver.dart'.
+// Try calling using ?. instead.
+//   a.foo();
+//     ^^^
+//
+// pkg/front_end/testcases/nnbd/nullable_receiver.dart:24:5: Error: Property 'bar' cannot be accessed on 'A?' because it is potentially null.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/nullable_receiver.dart'.
+// Try accessing using ?. instead.
+//   a.bar;
+//     ^^^
+//
+// pkg/front_end/testcases/nnbd/nullable_receiver.dart:25:5: Error: Property 'baz' cannot be accessed on 'A?' because it is potentially null.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/nullable_receiver.dart'.
+// Try accessing using ?. instead.
+//   a.baz = 42;
+//     ^^^
+//
+// pkg/front_end/testcases/nnbd/nullable_receiver.dart:26:4: Error: Can't use an expression of type 'A?' as a function because it's potentially null.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/nullable_receiver.dart'.
+// Try calling using ?.call instead.
+//   a();
+//    ^
+//
+// pkg/front_end/testcases/nnbd/nullable_receiver.dart:27:13: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//   b.toString(0);
+//             ^
+//
+// pkg/front_end/testcases/nnbd/nullable_receiver.dart:29:17: Error: Can't tear off method 'call' from a potentially null value.
+//   Function f1 = a;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/nullable_receiver.dart:30:24: Error: Can't tear off method 'call' from a potentially null value.
+//   void Function() f2 = a;
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/nullable_receiver.dart:31:25: Error: Can't tear off method 'call' from a potentially null value.
+//   void Function()? f3 = a;
+//                         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method foo() → dynamic {}
+  get bar() → core::int
+    return 42;
+  set baz(core::int value) → void {}
+  method call() → void {}
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+  method toString([core::int extra = #C1]) → core::String
+    return super.{core::Object::toString}();
+}
+static method error(core::String? s, self::A? a, self::B? b) → dynamic {
+  invalid-expression "pkg/front_end/testcases/nnbd/nullable_receiver.dart:20:5: Error: Property 'length' cannot be accessed on 'String?' because it is potentially null.
+Try accessing using ?. instead.
+  s.length;
+    ^^^^^^" in s.{core::String::length}{<nullable>}.{core::int};
+  invalid-expression "pkg/front_end/testcases/nnbd/nullable_receiver.dart:21:5: Error: Method 'substring' cannot be called on 'String?' because it is potentially null.
+Try calling using ?. instead.
+  s.substring(1, 1);
+    ^^^^^^^^^" in s.{core::String::substring}{<nullable>}.(1, 1){(core::int, [core::int?]) → core::String};
+  invalid-expression "pkg/front_end/testcases/nnbd/nullable_receiver.dart:23:5: Error: Method 'foo' cannot be called on 'A?' because it is potentially null.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/nullable_receiver.dart'.
+Try calling using ?. instead.
+  a.foo();
+    ^^^" in a.{self::A::foo}{<nullable>}.(){() → dynamic};
+  invalid-expression "pkg/front_end/testcases/nnbd/nullable_receiver.dart:24:5: Error: Property 'bar' cannot be accessed on 'A?' because it is potentially null.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/nullable_receiver.dart'.
+Try accessing using ?. instead.
+  a.bar;
+    ^^^" in a.{self::A::bar}{<nullable>}.{core::int};
+  invalid-expression "pkg/front_end/testcases/nnbd/nullable_receiver.dart:25:5: Error: Property 'baz' cannot be accessed on 'A?' because it is potentially null.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/nullable_receiver.dart'.
+Try accessing using ?. instead.
+  a.baz = 42;
+    ^^^" in a.{self::A::baz}{<nullable>}. = 42;
+  invalid-expression "pkg/front_end/testcases/nnbd/nullable_receiver.dart:26:4: Error: Can't use an expression of type 'A?' as a function because it's potentially null.
+ - 'A' is from 'pkg/front_end/testcases/nnbd/nullable_receiver.dart'.
+Try calling using ?.call instead.
+  a();
+   ^" in a.{self::A::call}{<nullable>}.(){() → void};
+  invalid-expression "pkg/front_end/testcases/nnbd/nullable_receiver.dart:27:13: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+  b.toString(0);
+            ^" in b.{core::Object::toString}{<inapplicable>}.(0){(invalid-type) → invalid-type};
+  core::Function f1 = invalid-expression "pkg/front_end/testcases/nnbd/nullable_receiver.dart:29:17: Error: Can't tear off method 'call' from a potentially null value.
+  Function f1 = a;
+                ^" in a as{TypeError} core::Function;
+  () → void f2 = invalid-expression "pkg/front_end/testcases/nnbd/nullable_receiver.dart:30:24: Error: Can't tear off method 'call' from a potentially null value.
+  void Function() f2 = a;
+                       ^" in a as{TypeError} () → void;
+  () →? void f3 = invalid-expression "pkg/front_end/testcases/nnbd/nullable_receiver.dart:31:25: Error: Can't tear off method 'call' from a potentially null value.
+  void Function()? f3 = a;
+                        ^" in a as{TypeError} () →? void;
+}
+static method ok<T extends core::Object?>(core::String? s, self::A? a, self::ok::T% t, self::B? b, core::Invocation i) → dynamic {
+  s =={core::String::==}{(core::Object) → core::bool} s;
+  a =={core::Object::==}{(core::Object) → core::bool} a;
+  t =={core::Object::==}{(core::Object) → core::bool} t;
+  b =={core::Object::==}{(core::Object) → core::bool} b;
+  s.{core::Object::hashCode}{core::int};
+  a.{core::Object::hashCode}{core::int};
+  t.{core::Object::hashCode}{core::int};
+  b.{core::Object::hashCode}{core::int};
+  s.{core::Object::toString}(){() → core::String};
+  a.{core::Object::toString}(){() → core::String};
+  t.{core::Object::toString}(){() → core::String};
+  b.{core::Object::toString}(){() → core::String};
+  try {
+    s.{core::Object::noSuchMethod}(i){(core::Invocation) → dynamic};
+  }
+  on core::Object catch(final core::Object e, final core::StackTrace t) {
+  }
+  try {
+    a.{core::Object::noSuchMethod}(i){(core::Invocation) → dynamic};
+  }
+  on core::Object catch(final core::Object e, final core::StackTrace t) {
+  }
+  try {
+    t.{core::Object::noSuchMethod}(i){(core::Invocation) → dynamic};
+  }
+  on core::Object catch(final core::Object e, final core::StackTrace t) {
+  }
+  try {
+    b.{core::Object::noSuchMethod}(i){(core::Invocation) → dynamic};
+  }
+  on core::Object catch(final core::Object e, final core::StackTrace t) {
+  }
+  s.{core::Object::runtimeType}{core::Type};
+  a.{core::Object::runtimeType}{core::Type};
+  t.{core::Object::runtimeType}{core::Type};
+  b.{core::Object::runtimeType}{core::Type};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 42
+}
diff --git a/pkg/front_end/testcases/nnbd/nullable_rhs_of_typedef.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/nullable_rhs_of_typedef.dart.weak.modular.expect
new file mode 100644
index 0000000..5e0924e
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/nullable_rhs_of_typedef.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/nullable_rhs_of_typedef.dart:7:11: Error: Can't create typedef from nullable type.
+// typedef F = void Function()?;
+//           ^
+//
+import self as self;
+
+typedef F = invalid-type;
+static method foo(() → void x) → void {
+  self::bar(x);
+  self::bar(null);
+  self::baz(x);
+  self::baz(null);
+}
+static method bar(invalid-type x) → void {}
+static method baz(invalid-type x) → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/nullable_setter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/nullable_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..297e474
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/nullable_setter.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field core::String m = "";
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  set setter(core::String v) → void {}
+  operator []=(core::int index, core::String value) → void {}
+}
+extension _extension#0 on self::C? {
+  operator []= = self::_extension#0|[]=;
+  set setter = self::_extension#0|set#setter;
+}
+static method _extension#0|set#setter(lowered final self::C? #this, core::String v) → void {
+  let final self::C? #t1 = #this in #t1 == null ?{core::String?} null : #t1{self::C}.{self::C::m} = v;
+}
+static method _extension#0|[]=(lowered final self::C? #this, core::int index, core::String value) → void {
+  let final self::C? #t2 = #this in #t2 == null ?{core::String?} null : #t2{self::C}.{self::C::m} = "${index}${value}";
+}
+static method main() → dynamic {
+  self::C? c = new self::C::•() as{ForNonNullableByDefault} self::C?;
+  self::expect("", let final self::C? #t3 = c in #t3 == null ?{core::String?} null : #t3{self::C}.{self::C::m}{core::String});
+  self::_extension#0|set#setter(c, "42");
+  self::expect("42", let final self::C? #t4 = c in #t4 == null ?{core::String?} null : #t4{self::C}.{self::C::m}{core::String});
+  self::_extension#0|[]=(c, 42, "87");
+  self::expect("4287", let final self::C? #t5 = c in #t5 == null ?{core::String?} null : #t5{self::C}.{self::C::m}{core::String});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/nnbd/numbers.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/numbers.dart.weak.modular.expect
new file mode 100644
index 0000000..babfb04
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/numbers.dart.weak.modular.expect
@@ -0,0 +1,413 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method add<X extends core::num, Y extends core::int, Z extends core::double>(core::num n, core::int i, core::double d, self::add::X x, self::add::Y y, self::add::Z z) → dynamic {
+  core::num n_n = n.{core::num::+}(n){(core::num) → core::num};
+  core::num n_i = n.{core::num::+}(i){(core::num) → core::num};
+  core::double n_d = n.{core::num::+}(d){(core::num) → core::double};
+  core::num n_x = n.{core::num::+}(x){(core::num) → core::num};
+  core::num n_y = n.{core::num::+}(y){(core::num) → core::num};
+  core::double n_z = n.{core::num::+}(z){(core::num) → core::double};
+  core::num i_n = i.{core::num::+}(n){(core::num) → core::num};
+  core::int i_i = i.{core::num::+}(i){(core::num) → core::int};
+  core::double i_d = i.{core::num::+}(d){(core::num) → core::double};
+  core::num i_x = i.{core::num::+}(x){(core::num) → core::num};
+  core::int i_y = i.{core::num::+}(y){(core::num) → core::int};
+  core::double i_z = i.{core::num::+}(z){(core::num) → core::double};
+  core::double d_n = d.{core::double::+}(n){(core::num) → core::double};
+  core::double d_i = d.{core::double::+}(i){(core::num) → core::double};
+  core::double d_d = d.{core::double::+}(d){(core::num) → core::double};
+  core::double d_x = d.{core::double::+}(x){(core::num) → core::double};
+  core::double d_y = d.{core::double::+}(y){(core::num) → core::double};
+  core::double d_z = d.{core::double::+}(z){(core::num) → core::double};
+  core::num x_n = x.{core::num::+}(n){(core::num) → core::num};
+  core::num x_i = x.{core::num::+}(i){(core::num) → core::num};
+  core::double x_d = x.{core::num::+}(d){(core::num) → core::double};
+  core::num x_x = x.{core::num::+}(x){(core::num) → core::num};
+  core::num x_y = x.{core::num::+}(y){(core::num) → core::num};
+  core::double x_z = x.{core::num::+}(z){(core::num) → core::double};
+  core::num y_n = y.{core::num::+}(n){(core::num) → core::num};
+  core::int y_i = y.{core::num::+}(i){(core::num) → core::int};
+  core::double y_d = y.{core::num::+}(d){(core::num) → core::double};
+  core::num y_x = y.{core::num::+}(x){(core::num) → core::num};
+  core::int y_y = y.{core::num::+}(y){(core::num) → core::int};
+  core::double y_z = y.{core::num::+}(z){(core::num) → core::double};
+  core::double z_n = z.{core::double::+}(n){(core::num) → core::double};
+  core::double z_i = z.{core::double::+}(i){(core::num) → core::double};
+  core::double z_d = z.{core::double::+}(d){(core::num) → core::double};
+  core::double z_x = z.{core::double::+}(x){(core::num) → core::double};
+  core::double z_y = z.{core::double::+}(y){(core::num) → core::double};
+  core::double z_z = z.{core::double::+}(z){(core::num) → core::double};
+}
+static method sub<X extends core::num, Y extends core::int, Z extends core::double>(core::num n, core::int i, core::double d, self::sub::X x, self::sub::Y y, self::sub::Z z) → dynamic {
+  core::num n_n = n.{core::num::-}(n){(core::num) → core::num};
+  core::num n_i = n.{core::num::-}(i){(core::num) → core::num};
+  core::double n_d = n.{core::num::-}(d){(core::num) → core::double};
+  core::num n_x = n.{core::num::-}(x){(core::num) → core::num};
+  core::num n_y = n.{core::num::-}(y){(core::num) → core::num};
+  core::double n_z = n.{core::num::-}(z){(core::num) → core::double};
+  core::num i_n = i.{core::num::-}(n){(core::num) → core::num};
+  core::int i_i = i.{core::num::-}(i){(core::num) → core::int};
+  core::double i_d = i.{core::num::-}(d){(core::num) → core::double};
+  core::num i_x = i.{core::num::-}(x){(core::num) → core::num};
+  core::int i_y = i.{core::num::-}(y){(core::num) → core::int};
+  core::double i_z = i.{core::num::-}(z){(core::num) → core::double};
+  core::double d_n = d.{core::double::-}(n){(core::num) → core::double};
+  core::double d_i = d.{core::double::-}(i){(core::num) → core::double};
+  core::double d_d = d.{core::double::-}(d){(core::num) → core::double};
+  core::double d_x = d.{core::double::-}(x){(core::num) → core::double};
+  core::double d_y = d.{core::double::-}(y){(core::num) → core::double};
+  core::double d_z = d.{core::double::-}(z){(core::num) → core::double};
+  core::num x_n = x.{core::num::-}(n){(core::num) → core::num};
+  core::num x_i = x.{core::num::-}(i){(core::num) → core::num};
+  core::double x_d = x.{core::num::-}(d){(core::num) → core::double};
+  core::num x_x = x.{core::num::-}(x){(core::num) → core::num};
+  core::num x_y = x.{core::num::-}(y){(core::num) → core::num};
+  core::double x_z = x.{core::num::-}(z){(core::num) → core::double};
+  core::num y_n = y.{core::num::-}(n){(core::num) → core::num};
+  core::int y_i = y.{core::num::-}(i){(core::num) → core::int};
+  core::double y_d = y.{core::num::-}(d){(core::num) → core::double};
+  core::num y_x = y.{core::num::-}(x){(core::num) → core::num};
+  core::int y_y = y.{core::num::-}(y){(core::num) → core::int};
+  core::double y_z = y.{core::num::-}(z){(core::num) → core::double};
+  core::double z_n = z.{core::double::-}(n){(core::num) → core::double};
+  core::double z_i = z.{core::double::-}(i){(core::num) → core::double};
+  core::double z_d = z.{core::double::-}(d){(core::num) → core::double};
+  core::double z_x = z.{core::double::-}(x){(core::num) → core::double};
+  core::double z_y = z.{core::double::-}(y){(core::num) → core::double};
+  core::double z_z = z.{core::double::-}(z){(core::num) → core::double};
+}
+static method mul<X extends core::num, Y extends core::int, Z extends core::double>(core::num n, core::int i, core::double d, self::mul::X x, self::mul::Y y, self::mul::Z z) → dynamic {
+  core::num n_n = n.{core::num::*}(n){(core::num) → core::num};
+  core::num n_i = n.{core::num::*}(i){(core::num) → core::num};
+  core::double n_d = n.{core::num::*}(d){(core::num) → core::double};
+  core::num n_x = n.{core::num::*}(x){(core::num) → core::num};
+  core::num n_y = n.{core::num::*}(y){(core::num) → core::num};
+  core::double n_z = n.{core::num::*}(z){(core::num) → core::double};
+  core::num i_n = i.{core::num::*}(n){(core::num) → core::num};
+  core::int i_i = i.{core::num::*}(i){(core::num) → core::int};
+  core::double i_d = i.{core::num::*}(d){(core::num) → core::double};
+  core::num i_x = i.{core::num::*}(x){(core::num) → core::num};
+  core::int i_y = i.{core::num::*}(y){(core::num) → core::int};
+  core::double i_z = i.{core::num::*}(z){(core::num) → core::double};
+  core::double d_n = d.{core::double::*}(n){(core::num) → core::double};
+  core::double d_i = d.{core::double::*}(i){(core::num) → core::double};
+  core::double d_d = d.{core::double::*}(d){(core::num) → core::double};
+  core::double d_x = d.{core::double::*}(x){(core::num) → core::double};
+  core::double d_y = d.{core::double::*}(y){(core::num) → core::double};
+  core::double d_z = d.{core::double::*}(z){(core::num) → core::double};
+  core::num x_n = x.{core::num::*}(n){(core::num) → core::num};
+  core::num x_i = x.{core::num::*}(i){(core::num) → core::num};
+  core::double x_d = x.{core::num::*}(d){(core::num) → core::double};
+  core::num x_x = x.{core::num::*}(x){(core::num) → core::num};
+  core::num x_y = x.{core::num::*}(y){(core::num) → core::num};
+  core::double x_z = x.{core::num::*}(z){(core::num) → core::double};
+  core::num y_n = y.{core::num::*}(n){(core::num) → core::num};
+  core::int y_i = y.{core::num::*}(i){(core::num) → core::int};
+  core::double y_d = y.{core::num::*}(d){(core::num) → core::double};
+  core::num y_x = y.{core::num::*}(x){(core::num) → core::num};
+  core::int y_y = y.{core::num::*}(y){(core::num) → core::int};
+  core::double y_z = y.{core::num::*}(z){(core::num) → core::double};
+  core::double z_n = z.{core::double::*}(n){(core::num) → core::double};
+  core::double z_i = z.{core::double::*}(i){(core::num) → core::double};
+  core::double z_d = z.{core::double::*}(d){(core::num) → core::double};
+  core::double z_x = z.{core::double::*}(x){(core::num) → core::double};
+  core::double z_y = z.{core::double::*}(y){(core::num) → core::double};
+  core::double z_z = z.{core::double::*}(z){(core::num) → core::double};
+}
+static method mod<X extends core::num, Y extends core::int, Z extends core::double>(core::num n, core::int i, core::double d, self::mod::X x, self::mod::Y y, self::mod::Z z) → dynamic {
+  core::num n_n = n.{core::num::%}(n){(core::num) → core::num};
+  core::num n_i = n.{core::num::%}(i){(core::num) → core::num};
+  core::double n_d = n.{core::num::%}(d){(core::num) → core::double};
+  core::num n_x = n.{core::num::%}(x){(core::num) → core::num};
+  core::num n_y = n.{core::num::%}(y){(core::num) → core::num};
+  core::double n_z = n.{core::num::%}(z){(core::num) → core::double};
+  core::num i_n = i.{core::num::%}(n){(core::num) → core::num};
+  core::int i_i = i.{core::num::%}(i){(core::num) → core::int};
+  core::double i_d = i.{core::num::%}(d){(core::num) → core::double};
+  core::num i_x = i.{core::num::%}(x){(core::num) → core::num};
+  core::int i_y = i.{core::num::%}(y){(core::num) → core::int};
+  core::double i_z = i.{core::num::%}(z){(core::num) → core::double};
+  core::double d_n = d.{core::double::%}(n){(core::num) → core::double};
+  core::double d_i = d.{core::double::%}(i){(core::num) → core::double};
+  core::double d_d = d.{core::double::%}(d){(core::num) → core::double};
+  core::double d_x = d.{core::double::%}(x){(core::num) → core::double};
+  core::double d_y = d.{core::double::%}(y){(core::num) → core::double};
+  core::double d_z = d.{core::double::%}(z){(core::num) → core::double};
+  core::num x_n = x.{core::num::%}(n){(core::num) → core::num};
+  core::num x_i = x.{core::num::%}(i){(core::num) → core::num};
+  core::double x_d = x.{core::num::%}(d){(core::num) → core::double};
+  core::num x_x = x.{core::num::%}(x){(core::num) → core::num};
+  core::num x_y = x.{core::num::%}(y){(core::num) → core::num};
+  core::double x_z = x.{core::num::%}(z){(core::num) → core::double};
+  core::num y_n = y.{core::num::%}(n){(core::num) → core::num};
+  core::int y_i = y.{core::num::%}(i){(core::num) → core::int};
+  core::double y_d = y.{core::num::%}(d){(core::num) → core::double};
+  core::num y_x = y.{core::num::%}(x){(core::num) → core::num};
+  core::int y_y = y.{core::num::%}(y){(core::num) → core::int};
+  core::double y_z = y.{core::num::%}(z){(core::num) → core::double};
+  core::double z_n = z.{core::double::%}(n){(core::num) → core::double};
+  core::double z_i = z.{core::double::%}(i){(core::num) → core::double};
+  core::double z_d = z.{core::double::%}(d){(core::num) → core::double};
+  core::double z_x = z.{core::double::%}(x){(core::num) → core::double};
+  core::double z_y = z.{core::double::%}(y){(core::num) → core::double};
+  core::double z_z = z.{core::double::%}(z){(core::num) → core::double};
+}
+static method remainder<X extends core::num, Y extends core::int, Z extends core::double>(core::num n, core::int i, core::double d, self::remainder::X x, self::remainder::Y y, self::remainder::Z z) → dynamic {
+  core::num n_n = n.{core::num::remainder}(n){(core::num) → core::num};
+  core::num n_i = n.{core::num::remainder}(i){(core::num) → core::num};
+  core::double n_d = n.{core::num::remainder}(d){(core::num) → core::double};
+  core::num n_x = n.{core::num::remainder}(x){(core::num) → core::num};
+  core::num n_y = n.{core::num::remainder}(y){(core::num) → core::num};
+  core::double n_z = n.{core::num::remainder}(z){(core::num) → core::double};
+  core::num i_n = i.{core::num::remainder}(n){(core::num) → core::num};
+  core::int i_i = i.{core::num::remainder}(i){(core::num) → core::int};
+  core::double i_d = i.{core::num::remainder}(d){(core::num) → core::double};
+  core::num i_x = i.{core::num::remainder}(x){(core::num) → core::num};
+  core::int i_y = i.{core::num::remainder}(y){(core::num) → core::int};
+  core::double i_z = i.{core::num::remainder}(z){(core::num) → core::double};
+  core::double d_n = d.{core::double::remainder}(n){(core::num) → core::double};
+  core::double d_i = d.{core::double::remainder}(i){(core::num) → core::double};
+  core::double d_d = d.{core::double::remainder}(d){(core::num) → core::double};
+  core::double d_x = d.{core::double::remainder}(x){(core::num) → core::double};
+  core::double d_y = d.{core::double::remainder}(y){(core::num) → core::double};
+  core::double d_z = d.{core::double::remainder}(z){(core::num) → core::double};
+  core::num x_n = x.{core::num::remainder}(n){(core::num) → core::num};
+  core::num x_i = x.{core::num::remainder}(i){(core::num) → core::num};
+  core::double x_d = x.{core::num::remainder}(d){(core::num) → core::double};
+  core::num x_x = x.{core::num::remainder}(x){(core::num) → core::num};
+  core::num x_y = x.{core::num::remainder}(y){(core::num) → core::num};
+  core::double x_z = x.{core::num::remainder}(z){(core::num) → core::double};
+  core::num y_n = y.{core::num::remainder}(n){(core::num) → core::num};
+  core::int y_i = y.{core::num::remainder}(i){(core::num) → core::int};
+  core::double y_d = y.{core::num::remainder}(d){(core::num) → core::double};
+  core::num y_x = y.{core::num::remainder}(x){(core::num) → core::num};
+  core::int y_y = y.{core::num::remainder}(y){(core::num) → core::int};
+  core::double y_z = y.{core::num::remainder}(z){(core::num) → core::double};
+  core::double z_n = z.{core::double::remainder}(n){(core::num) → core::double};
+  core::double z_i = z.{core::double::remainder}(i){(core::num) → core::double};
+  core::double z_d = z.{core::double::remainder}(d){(core::num) → core::double};
+  core::double z_x = z.{core::double::remainder}(x){(core::num) → core::double};
+  core::double z_y = z.{core::double::remainder}(y){(core::num) → core::double};
+  core::double z_z = z.{core::double::remainder}(z){(core::num) → core::double};
+}
+static method clamp<X extends core::num, Y extends core::int, Z extends core::double>(core::num n, core::int i, core::double d, self::clamp::X x, self::clamp::Y y, self::clamp::Z z) → dynamic {
+  core::num n_n_n = n.{core::num::clamp}(n, n){(core::num, core::num) → core::num};
+  core::num n_i_n = n.{core::num::clamp}(i, n){(core::num, core::num) → core::num};
+  core::num n_d_n = n.{core::num::clamp}(d, n){(core::num, core::num) → core::num};
+  core::num n_x_n = n.{core::num::clamp}(x, n){(core::num, core::num) → core::num};
+  core::num n_y_n = n.{core::num::clamp}(y, n){(core::num, core::num) → core::num};
+  core::num n_z_n = n.{core::num::clamp}(z, n){(core::num, core::num) → core::num};
+  core::num n_n_i = n.{core::num::clamp}(n, i){(core::num, core::num) → core::num};
+  core::num n_i_i = n.{core::num::clamp}(i, i){(core::num, core::num) → core::num};
+  core::num n_d_i = n.{core::num::clamp}(d, i){(core::num, core::num) → core::num};
+  core::num n_x_i = n.{core::num::clamp}(x, i){(core::num, core::num) → core::num};
+  core::num n_y_i = n.{core::num::clamp}(y, i){(core::num, core::num) → core::num};
+  core::num n_z_i = n.{core::num::clamp}(z, i){(core::num, core::num) → core::num};
+  core::num n_n_d = n.{core::num::clamp}(n, d){(core::num, core::num) → core::num};
+  core::num n_i_d = n.{core::num::clamp}(i, d){(core::num, core::num) → core::num};
+  core::num n_d_d = n.{core::num::clamp}(d, d){(core::num, core::num) → core::num};
+  core::num n_x_d = n.{core::num::clamp}(x, d){(core::num, core::num) → core::num};
+  core::num n_y_d = n.{core::num::clamp}(y, d){(core::num, core::num) → core::num};
+  core::num n_z_d = n.{core::num::clamp}(z, d){(core::num, core::num) → core::num};
+  core::num n_n_x = n.{core::num::clamp}(n, x){(core::num, core::num) → core::num};
+  core::num n_i_x = n.{core::num::clamp}(i, x){(core::num, core::num) → core::num};
+  core::num n_d_x = n.{core::num::clamp}(d, x){(core::num, core::num) → core::num};
+  core::num n_x_x = n.{core::num::clamp}(x, x){(core::num, core::num) → core::num};
+  core::num n_y_x = n.{core::num::clamp}(y, x){(core::num, core::num) → core::num};
+  core::num n_z_x = n.{core::num::clamp}(z, x){(core::num, core::num) → core::num};
+  core::num n_n_y = n.{core::num::clamp}(n, y){(core::num, core::num) → core::num};
+  core::num n_i_y = n.{core::num::clamp}(i, y){(core::num, core::num) → core::num};
+  core::num n_d_y = n.{core::num::clamp}(d, y){(core::num, core::num) → core::num};
+  core::num n_x_y = n.{core::num::clamp}(x, y){(core::num, core::num) → core::num};
+  core::num n_y_y = n.{core::num::clamp}(y, y){(core::num, core::num) → core::num};
+  core::num n_z_y = n.{core::num::clamp}(z, y){(core::num, core::num) → core::num};
+  core::num n_n_z = n.{core::num::clamp}(n, z){(core::num, core::num) → core::num};
+  core::num n_i_z = n.{core::num::clamp}(i, z){(core::num, core::num) → core::num};
+  core::num n_d_z = n.{core::num::clamp}(d, z){(core::num, core::num) → core::num};
+  core::num n_x_z = n.{core::num::clamp}(x, z){(core::num, core::num) → core::num};
+  core::num n_y_z = n.{core::num::clamp}(y, z){(core::num, core::num) → core::num};
+  core::num n_z_z = n.{core::num::clamp}(z, z){(core::num, core::num) → core::num};
+  core::num i_n_n = i.{core::num::clamp}(n, n){(core::num, core::num) → core::num};
+  core::num i_i_n = i.{core::num::clamp}(i, n){(core::num, core::num) → core::num};
+  core::num i_d_n = i.{core::num::clamp}(d, n){(core::num, core::num) → core::num};
+  core::num i_x_n = i.{core::num::clamp}(x, n){(core::num, core::num) → core::num};
+  core::num i_y_n = i.{core::num::clamp}(y, n){(core::num, core::num) → core::num};
+  core::num i_z_n = i.{core::num::clamp}(z, n){(core::num, core::num) → core::num};
+  core::num i_n_i = i.{core::num::clamp}(n, i){(core::num, core::num) → core::num};
+  core::int i_i_i = i.{core::num::clamp}(i, i){(core::num, core::num) → core::int};
+  core::num i_d_i = i.{core::num::clamp}(d, i){(core::num, core::num) → core::num};
+  core::num i_x_i = i.{core::num::clamp}(x, i){(core::num, core::num) → core::num};
+  core::int i_y_i = i.{core::num::clamp}(y, i){(core::num, core::num) → core::int};
+  core::num i_z_i = i.{core::num::clamp}(z, i){(core::num, core::num) → core::num};
+  core::num i_n_d = i.{core::num::clamp}(n, d){(core::num, core::num) → core::num};
+  core::num i_i_d = i.{core::num::clamp}(i, d){(core::num, core::num) → core::num};
+  core::num i_d_d = i.{core::num::clamp}(d, d){(core::num, core::num) → core::num};
+  core::num i_x_d = i.{core::num::clamp}(x, d){(core::num, core::num) → core::num};
+  core::num i_y_d = i.{core::num::clamp}(y, d){(core::num, core::num) → core::num};
+  core::num i_z_d = i.{core::num::clamp}(z, d){(core::num, core::num) → core::num};
+  core::num i_n_x = i.{core::num::clamp}(n, x){(core::num, core::num) → core::num};
+  core::num i_i_x = i.{core::num::clamp}(i, x){(core::num, core::num) → core::num};
+  core::num i_d_x = i.{core::num::clamp}(d, x){(core::num, core::num) → core::num};
+  core::num i_x_x = i.{core::num::clamp}(x, x){(core::num, core::num) → core::num};
+  core::num i_y_x = i.{core::num::clamp}(y, x){(core::num, core::num) → core::num};
+  core::num i_z_x = i.{core::num::clamp}(z, x){(core::num, core::num) → core::num};
+  core::num i_n_y = i.{core::num::clamp}(n, y){(core::num, core::num) → core::num};
+  core::int i_i_y = i.{core::num::clamp}(i, y){(core::num, core::num) → core::int};
+  core::num i_d_y = i.{core::num::clamp}(d, y){(core::num, core::num) → core::num};
+  core::num i_x_y = i.{core::num::clamp}(x, y){(core::num, core::num) → core::num};
+  core::int i_y_y = i.{core::num::clamp}(y, y){(core::num, core::num) → core::int};
+  core::num i_z_y = i.{core::num::clamp}(z, y){(core::num, core::num) → core::num};
+  core::num i_n_z = i.{core::num::clamp}(n, z){(core::num, core::num) → core::num};
+  core::num i_i_z = i.{core::num::clamp}(i, z){(core::num, core::num) → core::num};
+  core::num i_d_z = i.{core::num::clamp}(d, z){(core::num, core::num) → core::num};
+  core::num i_x_z = i.{core::num::clamp}(x, z){(core::num, core::num) → core::num};
+  core::num i_y_z = i.{core::num::clamp}(y, z){(core::num, core::num) → core::num};
+  core::num i_z_z = i.{core::num::clamp}(z, z){(core::num, core::num) → core::num};
+  core::num d_n_n = d.{core::num::clamp}(n, n){(core::num, core::num) → core::num};
+  core::num d_i_n = d.{core::num::clamp}(i, n){(core::num, core::num) → core::num};
+  core::num d_d_n = d.{core::num::clamp}(d, n){(core::num, core::num) → core::num};
+  core::num d_x_n = d.{core::num::clamp}(x, n){(core::num, core::num) → core::num};
+  core::num d_y_n = d.{core::num::clamp}(y, n){(core::num, core::num) → core::num};
+  core::num d_z_n = d.{core::num::clamp}(z, n){(core::num, core::num) → core::num};
+  core::num d_n_i = d.{core::num::clamp}(n, i){(core::num, core::num) → core::num};
+  core::num d_i_i = d.{core::num::clamp}(i, i){(core::num, core::num) → core::num};
+  core::num d_d_i = d.{core::num::clamp}(d, i){(core::num, core::num) → core::num};
+  core::num d_x_i = d.{core::num::clamp}(x, i){(core::num, core::num) → core::num};
+  core::num d_y_i = d.{core::num::clamp}(y, i){(core::num, core::num) → core::num};
+  core::num d_z_i = d.{core::num::clamp}(z, i){(core::num, core::num) → core::num};
+  core::num d_n_d = d.{core::num::clamp}(n, d){(core::num, core::num) → core::num};
+  core::num d_i_d = d.{core::num::clamp}(i, d){(core::num, core::num) → core::num};
+  core::double d_d_d = d.{core::num::clamp}(d, d){(core::num, core::num) → core::double};
+  core::num d_x_d = d.{core::num::clamp}(x, d){(core::num, core::num) → core::num};
+  core::num d_y_d = d.{core::num::clamp}(y, d){(core::num, core::num) → core::num};
+  core::double d_z_d = d.{core::num::clamp}(z, d){(core::num, core::num) → core::double};
+  core::num d_n_x = d.{core::num::clamp}(n, x){(core::num, core::num) → core::num};
+  core::num d_i_x = d.{core::num::clamp}(i, x){(core::num, core::num) → core::num};
+  core::num d_d_x = d.{core::num::clamp}(d, x){(core::num, core::num) → core::num};
+  core::num d_x_x = d.{core::num::clamp}(x, x){(core::num, core::num) → core::num};
+  core::num d_y_x = d.{core::num::clamp}(y, x){(core::num, core::num) → core::num};
+  core::num d_z_x = d.{core::num::clamp}(z, x){(core::num, core::num) → core::num};
+  core::num d_n_y = d.{core::num::clamp}(n, y){(core::num, core::num) → core::num};
+  core::num d_i_y = d.{core::num::clamp}(i, y){(core::num, core::num) → core::num};
+  core::num d_d_y = d.{core::num::clamp}(d, y){(core::num, core::num) → core::num};
+  core::num d_x_y = d.{core::num::clamp}(x, y){(core::num, core::num) → core::num};
+  core::num d_y_y = d.{core::num::clamp}(y, y){(core::num, core::num) → core::num};
+  core::num d_z_y = d.{core::num::clamp}(z, y){(core::num, core::num) → core::num};
+  core::num d_n_z = d.{core::num::clamp}(n, z){(core::num, core::num) → core::num};
+  core::num d_i_z = d.{core::num::clamp}(i, z){(core::num, core::num) → core::num};
+  core::double d_d_z = d.{core::num::clamp}(d, z){(core::num, core::num) → core::double};
+  core::num d_x_z = d.{core::num::clamp}(x, z){(core::num, core::num) → core::num};
+  core::num d_y_z = d.{core::num::clamp}(y, z){(core::num, core::num) → core::num};
+  core::double d_z_z = d.{core::num::clamp}(z, z){(core::num, core::num) → core::double};
+  core::num x_n_n = x.{core::num::clamp}(n, n){(core::num, core::num) → core::num};
+  core::num x_i_n = x.{core::num::clamp}(i, n){(core::num, core::num) → core::num};
+  core::num x_d_n = x.{core::num::clamp}(d, n){(core::num, core::num) → core::num};
+  core::num x_x_n = x.{core::num::clamp}(x, n){(core::num, core::num) → core::num};
+  core::num x_y_n = x.{core::num::clamp}(y, n){(core::num, core::num) → core::num};
+  core::num x_z_n = x.{core::num::clamp}(z, n){(core::num, core::num) → core::num};
+  core::num x_n_i = x.{core::num::clamp}(n, i){(core::num, core::num) → core::num};
+  core::num x_i_i = x.{core::num::clamp}(i, i){(core::num, core::num) → core::num};
+  core::num x_d_i = x.{core::num::clamp}(d, i){(core::num, core::num) → core::num};
+  core::num x_x_i = x.{core::num::clamp}(x, i){(core::num, core::num) → core::num};
+  core::num x_y_i = x.{core::num::clamp}(y, i){(core::num, core::num) → core::num};
+  core::num x_z_i = x.{core::num::clamp}(z, i){(core::num, core::num) → core::num};
+  core::num x_n_d = x.{core::num::clamp}(n, d){(core::num, core::num) → core::num};
+  core::num x_i_d = x.{core::num::clamp}(i, d){(core::num, core::num) → core::num};
+  core::num x_d_d = x.{core::num::clamp}(d, d){(core::num, core::num) → core::num};
+  core::num x_x_d = x.{core::num::clamp}(x, d){(core::num, core::num) → core::num};
+  core::num x_y_d = x.{core::num::clamp}(y, d){(core::num, core::num) → core::num};
+  core::num x_z_d = x.{core::num::clamp}(z, d){(core::num, core::num) → core::num};
+  core::num x_n_x = x.{core::num::clamp}(n, x){(core::num, core::num) → core::num};
+  core::num x_i_x = x.{core::num::clamp}(i, x){(core::num, core::num) → core::num};
+  core::num x_d_x = x.{core::num::clamp}(d, x){(core::num, core::num) → core::num};
+  core::num x_x_x = x.{core::num::clamp}(x, x){(core::num, core::num) → core::num};
+  core::num x_y_x = x.{core::num::clamp}(y, x){(core::num, core::num) → core::num};
+  core::num x_z_x = x.{core::num::clamp}(z, x){(core::num, core::num) → core::num};
+  core::num x_n_y = x.{core::num::clamp}(n, y){(core::num, core::num) → core::num};
+  core::num x_i_y = x.{core::num::clamp}(i, y){(core::num, core::num) → core::num};
+  core::num x_d_y = x.{core::num::clamp}(d, y){(core::num, core::num) → core::num};
+  core::num x_x_y = x.{core::num::clamp}(x, y){(core::num, core::num) → core::num};
+  core::num x_y_y = x.{core::num::clamp}(y, y){(core::num, core::num) → core::num};
+  core::num x_z_y = x.{core::num::clamp}(z, y){(core::num, core::num) → core::num};
+  core::num x_n_z = x.{core::num::clamp}(n, z){(core::num, core::num) → core::num};
+  core::num x_i_z = x.{core::num::clamp}(i, z){(core::num, core::num) → core::num};
+  core::num x_d_z = x.{core::num::clamp}(d, z){(core::num, core::num) → core::num};
+  core::num x_x_z = x.{core::num::clamp}(x, z){(core::num, core::num) → core::num};
+  core::num x_y_z = x.{core::num::clamp}(y, z){(core::num, core::num) → core::num};
+  core::num x_z_z = x.{core::num::clamp}(z, z){(core::num, core::num) → core::num};
+  core::num y_n_n = y.{core::num::clamp}(n, n){(core::num, core::num) → core::num};
+  core::num y_i_n = y.{core::num::clamp}(i, n){(core::num, core::num) → core::num};
+  core::num y_d_n = y.{core::num::clamp}(d, n){(core::num, core::num) → core::num};
+  core::num y_x_n = y.{core::num::clamp}(x, n){(core::num, core::num) → core::num};
+  core::num y_y_n = y.{core::num::clamp}(y, n){(core::num, core::num) → core::num};
+  core::num y_z_n = y.{core::num::clamp}(z, n){(core::num, core::num) → core::num};
+  core::num y_n_i = y.{core::num::clamp}(n, i){(core::num, core::num) → core::num};
+  core::int y_i_i = y.{core::num::clamp}(i, i){(core::num, core::num) → core::int};
+  core::num y_d_i = y.{core::num::clamp}(d, i){(core::num, core::num) → core::num};
+  core::num y_x_i = y.{core::num::clamp}(x, i){(core::num, core::num) → core::num};
+  core::int y_y_i = y.{core::num::clamp}(y, i){(core::num, core::num) → core::int};
+  core::num y_z_i = y.{core::num::clamp}(z, i){(core::num, core::num) → core::num};
+  core::num y_n_d = y.{core::num::clamp}(n, d){(core::num, core::num) → core::num};
+  core::num y_i_d = y.{core::num::clamp}(i, d){(core::num, core::num) → core::num};
+  core::num y_d_d = y.{core::num::clamp}(d, d){(core::num, core::num) → core::num};
+  core::num y_x_d = y.{core::num::clamp}(x, d){(core::num, core::num) → core::num};
+  core::num y_y_d = y.{core::num::clamp}(y, d){(core::num, core::num) → core::num};
+  core::num y_z_d = y.{core::num::clamp}(z, d){(core::num, core::num) → core::num};
+  core::num y_n_x = y.{core::num::clamp}(n, x){(core::num, core::num) → core::num};
+  core::num y_i_x = y.{core::num::clamp}(i, x){(core::num, core::num) → core::num};
+  core::num y_d_x = y.{core::num::clamp}(d, x){(core::num, core::num) → core::num};
+  core::num y_x_x = y.{core::num::clamp}(x, x){(core::num, core::num) → core::num};
+  core::num y_y_x = y.{core::num::clamp}(y, x){(core::num, core::num) → core::num};
+  core::num y_z_x = y.{core::num::clamp}(z, x){(core::num, core::num) → core::num};
+  core::num y_n_y = y.{core::num::clamp}(n, y){(core::num, core::num) → core::num};
+  core::int y_i_y = y.{core::num::clamp}(i, y){(core::num, core::num) → core::int};
+  core::num y_d_y = y.{core::num::clamp}(d, y){(core::num, core::num) → core::num};
+  core::num y_x_y = y.{core::num::clamp}(x, y){(core::num, core::num) → core::num};
+  core::int y_y_y = y.{core::num::clamp}(y, y){(core::num, core::num) → core::int};
+  core::num y_z_y = y.{core::num::clamp}(z, y){(core::num, core::num) → core::num};
+  core::num y_n_z = y.{core::num::clamp}(n, z){(core::num, core::num) → core::num};
+  core::num y_i_z = y.{core::num::clamp}(i, z){(core::num, core::num) → core::num};
+  core::num y_d_z = y.{core::num::clamp}(d, z){(core::num, core::num) → core::num};
+  core::num y_x_z = y.{core::num::clamp}(x, z){(core::num, core::num) → core::num};
+  core::num y_y_z = y.{core::num::clamp}(y, z){(core::num, core::num) → core::num};
+  core::num y_z_z = y.{core::num::clamp}(z, z){(core::num, core::num) → core::num};
+  core::num z_n_n = z.{core::num::clamp}(n, n){(core::num, core::num) → core::num};
+  core::num z_i_n = z.{core::num::clamp}(i, n){(core::num, core::num) → core::num};
+  core::num z_d_n = z.{core::num::clamp}(d, n){(core::num, core::num) → core::num};
+  core::num z_x_n = z.{core::num::clamp}(x, n){(core::num, core::num) → core::num};
+  core::num z_y_n = z.{core::num::clamp}(y, n){(core::num, core::num) → core::num};
+  core::num z_z_n = z.{core::num::clamp}(z, n){(core::num, core::num) → core::num};
+  core::num z_n_i = z.{core::num::clamp}(n, i){(core::num, core::num) → core::num};
+  core::num z_i_i = z.{core::num::clamp}(i, i){(core::num, core::num) → core::num};
+  core::num z_d_i = z.{core::num::clamp}(d, i){(core::num, core::num) → core::num};
+  core::num z_x_i = z.{core::num::clamp}(x, i){(core::num, core::num) → core::num};
+  core::num z_y_i = z.{core::num::clamp}(y, i){(core::num, core::num) → core::num};
+  core::num z_z_i = z.{core::num::clamp}(z, i){(core::num, core::num) → core::num};
+  core::num z_n_d = z.{core::num::clamp}(n, d){(core::num, core::num) → core::num};
+  core::num z_i_d = z.{core::num::clamp}(i, d){(core::num, core::num) → core::num};
+  core::double z_d_d = z.{core::num::clamp}(d, d){(core::num, core::num) → core::double};
+  core::num z_x_d = z.{core::num::clamp}(x, d){(core::num, core::num) → core::num};
+  core::num z_y_d = z.{core::num::clamp}(y, d){(core::num, core::num) → core::num};
+  core::double z_z_d = z.{core::num::clamp}(z, d){(core::num, core::num) → core::double};
+  core::num z_n_x = z.{core::num::clamp}(n, x){(core::num, core::num) → core::num};
+  core::num z_i_x = z.{core::num::clamp}(i, x){(core::num, core::num) → core::num};
+  core::num z_d_x = z.{core::num::clamp}(d, x){(core::num, core::num) → core::num};
+  core::num z_x_x = z.{core::num::clamp}(x, x){(core::num, core::num) → core::num};
+  core::num z_y_x = z.{core::num::clamp}(y, x){(core::num, core::num) → core::num};
+  core::num z_z_x = z.{core::num::clamp}(z, x){(core::num, core::num) → core::num};
+  core::num z_n_y = z.{core::num::clamp}(n, y){(core::num, core::num) → core::num};
+  core::num z_i_y = z.{core::num::clamp}(i, y){(core::num, core::num) → core::num};
+  core::num z_d_y = z.{core::num::clamp}(d, y){(core::num, core::num) → core::num};
+  core::num z_x_y = z.{core::num::clamp}(x, y){(core::num, core::num) → core::num};
+  core::num z_y_y = z.{core::num::clamp}(y, y){(core::num, core::num) → core::num};
+  core::num z_z_y = z.{core::num::clamp}(z, y){(core::num, core::num) → core::num};
+  core::num z_n_z = z.{core::num::clamp}(n, z){(core::num, core::num) → core::num};
+  core::num z_i_z = z.{core::num::clamp}(i, z){(core::num, core::num) → core::num};
+  core::double z_d_z = z.{core::num::clamp}(d, z){(core::num, core::num) → core::double};
+  core::num z_x_z = z.{core::num::clamp}(x, z){(core::num, core::num) → core::num};
+  core::num z_y_z = z.{core::num::clamp}(y, z){(core::num, core::num) → core::num};
+  core::double z_z_z = z.{core::num::clamp}(z, z){(core::num, core::num) → core::double};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/numbers_inferred.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/numbers_inferred.dart.weak.modular.expect
new file mode 100644
index 0000000..7bd9497
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/numbers_inferred.dart.weak.modular.expect
@@ -0,0 +1,1054 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:10:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+//   int n_i = n + f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:12:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X n_x = n + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:13:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y n_y = n + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:14:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z n_z = n + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:19:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X i_x = i + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:20:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y i_y = i + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:21:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z i_z = i + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:24:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//   int d_i = d + f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:26:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+//   X d_x = d + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:27:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+//   Y d_y = d + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:28:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+//   Z d_z = d + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:31:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+//   int x_i = x + f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:33:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X x_x = x + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:34:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y x_y = x + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:35:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z x_z = x + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:40:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X y_x = y + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:41:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y y_y = y + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:42:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z y_z = y + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:45:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//   int z_i = z + f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:47:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+//   X z_x = z + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:48:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+//   Y z_y = z + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:49:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+//   Z z_z = z + f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:55:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+//   int n_i = n - f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:57:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X n_x = n - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:58:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y n_y = n - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:59:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z n_z = n - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:64:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X i_x = i - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:65:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y i_y = i - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:66:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z i_z = i - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:69:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//   int d_i = d - f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:71:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+//   X d_x = d - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:72:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+//   Y d_y = d - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:73:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+//   Z d_z = d - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:76:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+//   int x_i = x - f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:78:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X x_x = x - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:79:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y x_y = x - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:80:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z x_z = x - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:85:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X y_x = y - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:86:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y y_y = y - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:87:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z y_z = y - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:90:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//   int z_i = z - f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:92:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+//   X z_x = z - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:93:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+//   Y z_y = z - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:94:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+//   Z z_z = z - f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:100:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+//   int n_i = n * f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:102:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X n_x = n * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:103:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y n_y = n * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:104:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z n_z = n * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:109:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X i_x = i * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:110:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y i_y = i * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:111:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z i_z = i * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:114:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//   int d_i = d * f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:116:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+//   X d_x = d * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:117:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+//   Y d_y = d * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:118:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+//   Z d_z = d * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:121:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+//   int x_i = x * f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:123:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X x_x = x * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:124:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y x_y = x * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:125:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z x_z = x * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:130:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X y_x = y * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:131:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y y_y = y * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:132:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z y_z = y * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:135:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//   int z_i = z * f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:137:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+//   X z_x = z * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:138:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+//   Y z_y = z * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:139:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+//   Z z_z = z * f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:145:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+//   int n_i = n % f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:147:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X n_x = n % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:148:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y n_y = n % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:149:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z n_z = n % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:154:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X i_x = i % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:155:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y i_y = i % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:156:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z i_z = i % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:159:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//   int d_i = d % f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:161:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+//   X d_x = d % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:162:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+//   Y d_y = d % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:163:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+//   Z d_z = d % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:166:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+//   int x_i = x % f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:168:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X x_x = x % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:169:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y x_y = x % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:170:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z x_z = x % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:175:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X y_x = y % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:176:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y y_y = y % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:177:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z y_z = y % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:180:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//   int z_i = z % f();
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:182:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+//   X z_x = z % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:183:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+//   Y z_y = z % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:184:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+//   Z z_z = z % f();
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:190:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+//   int n_i = n.remainder(f());
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:192:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X n_x = n.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:193:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y n_y = n.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:194:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z n_z = n.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:199:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X i_x = i.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:200:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y i_y = i.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:201:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z i_z = i.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:204:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//   int d_i = d.remainder(f());
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:206:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+//   X d_x = d.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:207:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+//   Y d_y = d.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:208:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+//   Z d_z = d.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:211:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+//   int x_i = x.remainder(f());
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:213:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X x_x = x.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:214:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y x_y = x.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:215:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z x_z = x.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:220:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X y_x = y.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:221:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y y_y = y.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:222:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z y_z = y.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:225:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+//   int z_i = z.remainder(f());
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:227:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+//   X z_x = z.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:228:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+//   Y z_y = z.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:229:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+//   Z z_z = z.remainder(f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:235:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+//   int n_i = n.clamp(f(), f());
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:236:18: Error: A value of type 'num' can't be assigned to a variable of type 'double'.
+//   double n_d = n.clamp(f(), f());
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:237:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X n_x = n.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:238:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y n_y = n.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:239:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z n_z = n.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:243:18: Error: A value of type 'num' can't be assigned to a variable of type 'double'.
+//   double i_d = i.clamp(f(), f());
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:244:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X i_x = i.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:245:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y i_y = i.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:246:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z i_z = i.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:249:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+//   int d_i = d.clamp(f(), f());
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:251:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X d_x = d.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:252:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y d_y = d.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:253:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z d_z = d.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:256:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+//   int x_i = x.clamp(f(), f());
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:257:18: Error: A value of type 'num' can't be assigned to a variable of type 'double'.
+//   double x_d = x.clamp(f(), f());
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:258:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X x_x = x.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:259:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y x_y = x.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:260:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z x_z = x.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:264:18: Error: A value of type 'num' can't be assigned to a variable of type 'double'.
+//   double y_d = y.clamp(f(), f());
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:265:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X y_x = y.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:266:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y y_y = y.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:267:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z y_z = y.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:270:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+//   int z_i = z.clamp(f(), f());
+//               ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:272:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+//   X z_x = z.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:273:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+//   Y z_y = z.clamp(f(), f());
+//             ^
+//
+// pkg/front_end/testcases/nnbd/numbers_inferred.dart:274:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+//   Z z_z = z.clamp(f(), f());
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method f<T extends core::Object? = dynamic>() → self::f::T%
+  return throw "Unsupported";
+static method add<X extends core::num, Y extends core::int, Z extends core::double>(core::num n, core::int i, core::double d, self::add::X x, self::add::Y y, self::add::Z z) → dynamic {
+  core::num n_n = n.{core::num::+}(self::f<core::num>()){(core::num) → core::num};
+  core::int n_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:10:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+  int n_i = n + f();
+              ^" in n.{core::num::+}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double n_d = n.{core::num::+}(self::f<core::double>()){(core::num) → core::double};
+  self::add::X n_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:12:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X n_x = n + f();
+            ^" in n.{core::num::+}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::add::Y n_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:13:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y n_y = n + f();
+            ^" in n.{core::num::+}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::add::Z n_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:14:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z n_z = n + f();
+            ^" in n.{core::num::+}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num i_n = i.{core::num::+}(self::f<core::num>()){(core::num) → core::num};
+  core::int i_i = i.{core::num::+}(self::f<core::int>()){(core::num) → core::int};
+  core::double i_d = i.{core::num::+}(self::f<core::double>()){(core::num) → core::double};
+  self::add::X i_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:19:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X i_x = i + f();
+            ^" in i.{core::num::+}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::add::Y i_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:20:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y i_y = i + f();
+            ^" in i.{core::num::+}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::add::Z i_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:21:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z i_z = i + f();
+            ^" in i.{core::num::+}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num d_n = d.{core::double::+}(self::f<core::num>()){(core::num) → core::double};
+  core::int d_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:24:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  int d_i = d + f();
+              ^" in d.{core::double::+}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double d_d = d.{core::double::+}(self::f<core::num>()){(core::num) → core::double};
+  self::add::X d_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:26:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+  X d_x = d + f();
+            ^" in d.{core::double::+}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::add::Y d_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:27:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+  Y d_y = d + f();
+            ^" in d.{core::double::+}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::add::Z d_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:28:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+  Z d_z = d + f();
+            ^" in d.{core::double::+}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  core::num x_n = x.{core::num::+}(self::f<core::num>()){(core::num) → core::num};
+  core::int x_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:31:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+  int x_i = x + f();
+              ^" in x.{core::num::+}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double x_d = x.{core::num::+}(self::f<core::double>()){(core::num) → core::double};
+  self::add::X x_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:33:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X x_x = x + f();
+            ^" in x.{core::num::+}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::add::Y x_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:34:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y x_y = x + f();
+            ^" in x.{core::num::+}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::add::Z x_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:35:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z x_z = x + f();
+            ^" in x.{core::num::+}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num y_n = y.{core::num::+}(self::f<core::num>()){(core::num) → core::num};
+  core::int y_i = y.{core::num::+}(self::f<core::int>()){(core::num) → core::int};
+  core::double y_d = y.{core::num::+}(self::f<core::double>()){(core::num) → core::double};
+  self::add::X y_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:40:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X y_x = y + f();
+            ^" in y.{core::num::+}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::add::Y y_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:41:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y y_y = y + f();
+            ^" in y.{core::num::+}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::add::Z y_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:42:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z y_z = y + f();
+            ^" in y.{core::num::+}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num z_n = z.{core::double::+}(self::f<core::num>()){(core::num) → core::double};
+  core::int z_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:45:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  int z_i = z + f();
+              ^" in z.{core::double::+}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double z_d = z.{core::double::+}(self::f<core::num>()){(core::num) → core::double};
+  self::add::X z_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:47:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+  X z_x = z + f();
+            ^" in z.{core::double::+}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::add::Y z_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:48:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+  Y z_y = z + f();
+            ^" in z.{core::double::+}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::add::Z z_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:49:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+  Z z_z = z + f();
+            ^" in z.{core::double::+}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+}
+static method sub<X extends core::num, Y extends core::int, Z extends core::double>(core::num n, core::int i, core::double d, self::sub::X x, self::sub::Y y, self::sub::Z z) → dynamic {
+  core::num n_n = n.{core::num::-}(self::f<core::num>()){(core::num) → core::num};
+  core::int n_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:55:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+  int n_i = n - f();
+              ^" in n.{core::num::-}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double n_d = n.{core::num::-}(self::f<core::double>()){(core::num) → core::double};
+  self::sub::X n_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:57:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X n_x = n - f();
+            ^" in n.{core::num::-}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::sub::Y n_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:58:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y n_y = n - f();
+            ^" in n.{core::num::-}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::sub::Z n_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:59:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z n_z = n - f();
+            ^" in n.{core::num::-}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num i_n = i.{core::num::-}(self::f<core::num>()){(core::num) → core::num};
+  core::int i_i = i.{core::num::-}(self::f<core::int>()){(core::num) → core::int};
+  core::double i_d = i.{core::num::-}(self::f<core::double>()){(core::num) → core::double};
+  self::sub::X i_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:64:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X i_x = i - f();
+            ^" in i.{core::num::-}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::sub::Y i_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:65:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y i_y = i - f();
+            ^" in i.{core::num::-}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::sub::Z i_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:66:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z i_z = i - f();
+            ^" in i.{core::num::-}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num d_n = d.{core::double::-}(self::f<core::num>()){(core::num) → core::double};
+  core::int d_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:69:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  int d_i = d - f();
+              ^" in d.{core::double::-}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double d_d = d.{core::double::-}(self::f<core::num>()){(core::num) → core::double};
+  self::sub::X d_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:71:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+  X d_x = d - f();
+            ^" in d.{core::double::-}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::sub::Y d_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:72:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+  Y d_y = d - f();
+            ^" in d.{core::double::-}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::sub::Z d_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:73:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+  Z d_z = d - f();
+            ^" in d.{core::double::-}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  core::num x_n = x.{core::num::-}(self::f<core::num>()){(core::num) → core::num};
+  core::int x_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:76:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+  int x_i = x - f();
+              ^" in x.{core::num::-}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double x_d = x.{core::num::-}(self::f<core::double>()){(core::num) → core::double};
+  self::sub::X x_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:78:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X x_x = x - f();
+            ^" in x.{core::num::-}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::sub::Y x_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:79:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y x_y = x - f();
+            ^" in x.{core::num::-}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::sub::Z x_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:80:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z x_z = x - f();
+            ^" in x.{core::num::-}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num y_n = y.{core::num::-}(self::f<core::num>()){(core::num) → core::num};
+  core::int y_i = y.{core::num::-}(self::f<core::int>()){(core::num) → core::int};
+  core::double y_d = y.{core::num::-}(self::f<core::double>()){(core::num) → core::double};
+  self::sub::X y_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:85:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X y_x = y - f();
+            ^" in y.{core::num::-}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::sub::Y y_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:86:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y y_y = y - f();
+            ^" in y.{core::num::-}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::sub::Z y_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:87:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z y_z = y - f();
+            ^" in y.{core::num::-}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num z_n = z.{core::double::-}(self::f<core::num>()){(core::num) → core::double};
+  core::int z_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:90:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  int z_i = z - f();
+              ^" in z.{core::double::-}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double z_d = z.{core::double::-}(self::f<core::num>()){(core::num) → core::double};
+  self::sub::X z_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:92:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+  X z_x = z - f();
+            ^" in z.{core::double::-}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::sub::Y z_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:93:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+  Y z_y = z - f();
+            ^" in z.{core::double::-}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::sub::Z z_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:94:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+  Z z_z = z - f();
+            ^" in z.{core::double::-}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+}
+static method mul<X extends core::num, Y extends core::int, Z extends core::double>(core::num n, core::int i, core::double d, self::mul::X x, self::mul::Y y, self::mul::Z z) → dynamic {
+  core::num n_n = n.{core::num::*}(self::f<core::num>()){(core::num) → core::num};
+  core::int n_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:100:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+  int n_i = n * f();
+              ^" in n.{core::num::*}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double n_d = n.{core::num::*}(self::f<core::double>()){(core::num) → core::double};
+  self::mul::X n_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:102:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X n_x = n * f();
+            ^" in n.{core::num::*}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mul::Y n_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:103:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y n_y = n * f();
+            ^" in n.{core::num::*}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mul::Z n_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:104:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z n_z = n * f();
+            ^" in n.{core::num::*}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num i_n = i.{core::num::*}(self::f<core::num>()){(core::num) → core::num};
+  core::int i_i = i.{core::num::*}(self::f<core::int>()){(core::num) → core::int};
+  core::double i_d = i.{core::num::*}(self::f<core::double>()){(core::num) → core::double};
+  self::mul::X i_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:109:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X i_x = i * f();
+            ^" in i.{core::num::*}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mul::Y i_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:110:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y i_y = i * f();
+            ^" in i.{core::num::*}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mul::Z i_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:111:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z i_z = i * f();
+            ^" in i.{core::num::*}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num d_n = d.{core::double::*}(self::f<core::num>()){(core::num) → core::double};
+  core::int d_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:114:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  int d_i = d * f();
+              ^" in d.{core::double::*}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double d_d = d.{core::double::*}(self::f<core::num>()){(core::num) → core::double};
+  self::mul::X d_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:116:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+  X d_x = d * f();
+            ^" in d.{core::double::*}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::mul::Y d_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:117:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+  Y d_y = d * f();
+            ^" in d.{core::double::*}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::mul::Z d_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:118:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+  Z d_z = d * f();
+            ^" in d.{core::double::*}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  core::num x_n = x.{core::num::*}(self::f<core::num>()){(core::num) → core::num};
+  core::int x_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:121:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+  int x_i = x * f();
+              ^" in x.{core::num::*}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double x_d = x.{core::num::*}(self::f<core::double>()){(core::num) → core::double};
+  self::mul::X x_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:123:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X x_x = x * f();
+            ^" in x.{core::num::*}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mul::Y x_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:124:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y x_y = x * f();
+            ^" in x.{core::num::*}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mul::Z x_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:125:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z x_z = x * f();
+            ^" in x.{core::num::*}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num y_n = y.{core::num::*}(self::f<core::num>()){(core::num) → core::num};
+  core::int y_i = y.{core::num::*}(self::f<core::int>()){(core::num) → core::int};
+  core::double y_d = y.{core::num::*}(self::f<core::double>()){(core::num) → core::double};
+  self::mul::X y_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:130:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X y_x = y * f();
+            ^" in y.{core::num::*}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mul::Y y_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:131:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y y_y = y * f();
+            ^" in y.{core::num::*}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mul::Z y_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:132:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z y_z = y * f();
+            ^" in y.{core::num::*}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num z_n = z.{core::double::*}(self::f<core::num>()){(core::num) → core::double};
+  core::int z_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:135:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  int z_i = z * f();
+              ^" in z.{core::double::*}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double z_d = z.{core::double::*}(self::f<core::num>()){(core::num) → core::double};
+  self::mul::X z_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:137:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+  X z_x = z * f();
+            ^" in z.{core::double::*}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::mul::Y z_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:138:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+  Y z_y = z * f();
+            ^" in z.{core::double::*}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::mul::Z z_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:139:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+  Z z_z = z * f();
+            ^" in z.{core::double::*}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+}
+static method mod<X extends core::num, Y extends core::int, Z extends core::double>(core::num n, core::int i, core::double d, self::mod::X x, self::mod::Y y, self::mod::Z z) → dynamic {
+  core::num n_n = n.{core::num::%}(self::f<core::num>()){(core::num) → core::num};
+  core::int n_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:145:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+  int n_i = n % f();
+              ^" in n.{core::num::%}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double n_d = n.{core::num::%}(self::f<core::double>()){(core::num) → core::double};
+  self::mod::X n_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:147:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X n_x = n % f();
+            ^" in n.{core::num::%}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mod::Y n_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:148:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y n_y = n % f();
+            ^" in n.{core::num::%}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mod::Z n_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:149:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z n_z = n % f();
+            ^" in n.{core::num::%}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num i_n = i.{core::num::%}(self::f<core::num>()){(core::num) → core::num};
+  core::int i_i = i.{core::num::%}(self::f<core::int>()){(core::num) → core::int};
+  core::double i_d = i.{core::num::%}(self::f<core::double>()){(core::num) → core::double};
+  self::mod::X i_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:154:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X i_x = i % f();
+            ^" in i.{core::num::%}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mod::Y i_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:155:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y i_y = i % f();
+            ^" in i.{core::num::%}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mod::Z i_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:156:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z i_z = i % f();
+            ^" in i.{core::num::%}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num d_n = d.{core::double::%}(self::f<core::num>()){(core::num) → core::double};
+  core::int d_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:159:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  int d_i = d % f();
+              ^" in d.{core::double::%}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double d_d = d.{core::double::%}(self::f<core::num>()){(core::num) → core::double};
+  self::mod::X d_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:161:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+  X d_x = d % f();
+            ^" in d.{core::double::%}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::mod::Y d_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:162:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+  Y d_y = d % f();
+            ^" in d.{core::double::%}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::mod::Z d_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:163:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+  Z d_z = d % f();
+            ^" in d.{core::double::%}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  core::num x_n = x.{core::num::%}(self::f<core::num>()){(core::num) → core::num};
+  core::int x_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:166:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+  int x_i = x % f();
+              ^" in x.{core::num::%}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double x_d = x.{core::num::%}(self::f<core::double>()){(core::num) → core::double};
+  self::mod::X x_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:168:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X x_x = x % f();
+            ^" in x.{core::num::%}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mod::Y x_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:169:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y x_y = x % f();
+            ^" in x.{core::num::%}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mod::Z x_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:170:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z x_z = x % f();
+            ^" in x.{core::num::%}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num y_n = y.{core::num::%}(self::f<core::num>()){(core::num) → core::num};
+  core::int y_i = y.{core::num::%}(self::f<core::int>()){(core::num) → core::int};
+  core::double y_d = y.{core::num::%}(self::f<core::double>()){(core::num) → core::double};
+  self::mod::X y_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:175:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X y_x = y % f();
+            ^" in y.{core::num::%}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mod::Y y_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:176:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y y_y = y % f();
+            ^" in y.{core::num::%}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::mod::Z y_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:177:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z y_z = y % f();
+            ^" in y.{core::num::%}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num z_n = z.{core::double::%}(self::f<core::num>()){(core::num) → core::double};
+  core::int z_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:180:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  int z_i = z % f();
+              ^" in z.{core::double::%}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double z_d = z.{core::double::%}(self::f<core::num>()){(core::num) → core::double};
+  self::mod::X z_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:182:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+  X z_x = z % f();
+            ^" in z.{core::double::%}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::mod::Y z_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:183:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+  Y z_y = z % f();
+            ^" in z.{core::double::%}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::mod::Z z_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:184:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+  Z z_z = z % f();
+            ^" in z.{core::double::%}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+}
+static method remainder<X extends core::num, Y extends core::int, Z extends core::double>(core::num n, core::int i, core::double d, self::remainder::X x, self::remainder::Y y, self::remainder::Z z) → dynamic {
+  core::num n_n = n.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num};
+  core::int n_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:190:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+  int n_i = n.remainder(f());
+              ^" in n.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double n_d = n.{core::num::remainder}(self::f<core::double>()){(core::num) → core::double};
+  self::remainder::X n_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:192:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X n_x = n.remainder(f());
+            ^" in n.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::remainder::Y n_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:193:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y n_y = n.remainder(f());
+            ^" in n.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::remainder::Z n_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:194:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z n_z = n.remainder(f());
+            ^" in n.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num i_n = i.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num};
+  core::int i_i = i.{core::num::remainder}(self::f<core::int>()){(core::num) → core::int};
+  core::double i_d = i.{core::num::remainder}(self::f<core::double>()){(core::num) → core::double};
+  self::remainder::X i_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:199:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X i_x = i.remainder(f());
+            ^" in i.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::remainder::Y i_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:200:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y i_y = i.remainder(f());
+            ^" in i.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::remainder::Z i_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:201:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z i_z = i.remainder(f());
+            ^" in i.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::double d_n = d.{core::double::remainder}(self::f<core::num>()){(core::num) → core::double};
+  core::int d_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:204:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  int d_i = d.remainder(f());
+              ^" in d.{core::double::remainder}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double d_d = d.{core::double::remainder}(self::f<core::num>()){(core::num) → core::double};
+  self::remainder::X d_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:206:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+  X d_x = d.remainder(f());
+            ^" in d.{core::double::remainder}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::remainder::Y d_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:207:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+  Y d_y = d.remainder(f());
+            ^" in d.{core::double::remainder}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::remainder::Z d_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:208:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+  Z d_z = d.remainder(f());
+            ^" in d.{core::double::remainder}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  core::num x_n = x.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num};
+  core::int x_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:211:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+  int x_i = x.remainder(f());
+              ^" in x.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double x_d = x.{core::num::remainder}(self::f<core::double>()){(core::num) → core::double};
+  self::remainder::X x_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:213:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X x_x = x.remainder(f());
+            ^" in x.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::remainder::Y x_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:214:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y x_y = x.remainder(f());
+            ^" in x.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::remainder::Z x_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:215:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z x_z = x.remainder(f());
+            ^" in x.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num y_n = y.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num};
+  core::int y_i = y.{core::num::remainder}(self::f<core::int>()){(core::num) → core::int};
+  core::double y_d = y.{core::num::remainder}(self::f<core::double>()){(core::num) → core::double};
+  self::remainder::X y_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:220:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X y_x = y.remainder(f());
+            ^" in y.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::remainder::Y y_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:221:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y y_y = y.remainder(f());
+            ^" in y.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::remainder::Z y_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:222:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z y_z = y.remainder(f());
+            ^" in y.{core::num::remainder}(self::f<core::num>()){(core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::double z_n = z.{core::double::remainder}(self::f<core::num>()){(core::num) → core::double};
+  core::int z_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:225:15: Error: A value of type 'double' can't be assigned to a variable of type 'int'.
+  int z_i = z.remainder(f());
+              ^" in z.{core::double::remainder}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double z_d = z.{core::double::remainder}(self::f<core::num>()){(core::num) → core::double};
+  self::remainder::X z_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:227:13: Error: A value of type 'double' can't be assigned to a variable of type 'X'.
+  X z_x = z.remainder(f());
+            ^" in z.{core::double::remainder}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::remainder::Y z_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:228:13: Error: A value of type 'double' can't be assigned to a variable of type 'Y'.
+  Y z_y = z.remainder(f());
+            ^" in z.{core::double::remainder}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+  self::remainder::Z z_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:229:13: Error: A value of type 'double' can't be assigned to a variable of type 'Z'.
+  Z z_z = z.remainder(f());
+            ^" in z.{core::double::remainder}(self::f<core::num>()){(core::num) → core::double} as{TypeError,ForNonNullableByDefault} Never;
+}
+static method clamp<X extends core::num, Y extends core::int, Z extends core::double>(core::num n, core::int i, core::double d, self::clamp::X x, self::clamp::Y y, self::clamp::Z z) → dynamic {
+  core::num n_n = n.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num};
+  core::int n_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:235:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+  int n_i = n.clamp(f(), f());
+              ^" in n.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double n_d = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:236:18: Error: A value of type 'num' can't be assigned to a variable of type 'double'.
+  double n_d = n.clamp(f(), f());
+                 ^" in n.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::double;
+  self::clamp::X n_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:237:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X n_x = n.clamp(f(), f());
+            ^" in n.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::clamp::Y n_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:238:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y n_y = n.clamp(f(), f());
+            ^" in n.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::clamp::Z n_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:239:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z n_z = n.clamp(f(), f());
+            ^" in n.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num i_n = i.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num};
+  core::int i_i = i.{core::num::clamp}(self::f<core::int>(), self::f<core::int>()){(core::num, core::num) → core::int};
+  core::double i_d = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:243:18: Error: A value of type 'num' can't be assigned to a variable of type 'double'.
+  double i_d = i.clamp(f(), f());
+                 ^" in i.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::double;
+  self::clamp::X i_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:244:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X i_x = i.clamp(f(), f());
+            ^" in i.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::clamp::Y i_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:245:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y i_y = i.clamp(f(), f());
+            ^" in i.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::clamp::Z i_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:246:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z i_z = i.clamp(f(), f());
+            ^" in i.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num d_n = d.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num};
+  core::int d_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:249:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+  int d_i = d.clamp(f(), f());
+              ^" in d.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double d_d = d.{core::num::clamp}(self::f<core::double>(), self::f<core::double>()){(core::num, core::num) → core::double};
+  self::clamp::X d_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:251:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X d_x = d.clamp(f(), f());
+            ^" in d.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::clamp::Y d_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:252:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y d_y = d.clamp(f(), f());
+            ^" in d.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::clamp::Z d_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:253:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z d_z = d.clamp(f(), f());
+            ^" in d.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num x_n = x.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num};
+  core::int x_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:256:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+  int x_i = x.clamp(f(), f());
+              ^" in x.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double x_d = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:257:18: Error: A value of type 'num' can't be assigned to a variable of type 'double'.
+  double x_d = x.clamp(f(), f());
+                 ^" in x.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::double;
+  self::clamp::X x_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:258:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X x_x = x.clamp(f(), f());
+            ^" in x.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::clamp::Y x_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:259:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y x_y = x.clamp(f(), f());
+            ^" in x.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::clamp::Z x_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:260:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z x_z = x.clamp(f(), f());
+            ^" in x.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num y_n = y.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num};
+  core::int y_i = y.{core::num::clamp}(self::f<core::int>(), self::f<core::int>()){(core::num, core::num) → core::int};
+  core::double y_d = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:264:18: Error: A value of type 'num' can't be assigned to a variable of type 'double'.
+  double y_d = y.clamp(f(), f());
+                 ^" in y.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::double;
+  self::clamp::X y_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:265:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X y_x = y.clamp(f(), f());
+            ^" in y.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::clamp::Y y_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:266:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y y_y = y.clamp(f(), f());
+            ^" in y.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::clamp::Z y_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:267:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z y_z = y.clamp(f(), f());
+            ^" in y.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  core::num z_n = z.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num};
+  core::int z_i = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:270:15: Error: A value of type 'num' can't be assigned to a variable of type 'int'.
+  int z_i = z.clamp(f(), f());
+              ^" in z.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} core::int;
+  core::double z_d = z.{core::num::clamp}(self::f<core::double>(), self::f<core::double>()){(core::num, core::num) → core::double};
+  self::clamp::X z_x = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:272:13: Error: A value of type 'num' can't be assigned to a variable of type 'X'.
+  X z_x = z.clamp(f(), f());
+            ^" in z.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::clamp::Y z_y = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:273:13: Error: A value of type 'num' can't be assigned to a variable of type 'Y'.
+  Y z_y = z.clamp(f(), f());
+            ^" in z.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+  self::clamp::Z z_z = invalid-expression "pkg/front_end/testcases/nnbd/numbers_inferred.dart:274:13: Error: A value of type 'num' can't be assigned to a variable of type 'Z'.
+  Z z_z = z.clamp(f(), f());
+            ^" in z.{core::num::clamp}(self::f<core::num>(), self::f<core::num>()){(core::num, core::num) → core::num} as{TypeError,ForNonNullableByDefault} Never;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/override_checks.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/override_checks.dart.weak.modular.expect
new file mode 100644
index 0000000..ba12861
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/override_checks.dart.weak.modular.expect
@@ -0,0 +1,93 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/override_checks.dart:14:7: Error: The field 'B2.bar' has type 'num', which does not match the corresponding type, 'num?', in the overridden setter, 'B1.bar'.
+//   num bar = 3.14; // Error in strong mode and Warning in weak mode.
+//       ^
+// pkg/front_end/testcases/nnbd/override_checks.dart:8:12: Context: This is the overridden method ('bar').
+//   void set bar(num? value) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd/override_checks.dart:15:12: Error: The return type of the method 'B2.baz' is 'num?', which does not match the return type, 'num', of the overridden method, 'B1.baz'.
+// Change to a subtype of 'num'.
+//   num? get baz => null; // Error in strong mode and Warning in weak mode.
+//            ^
+// pkg/front_end/testcases/nnbd/override_checks.dart:9:11: Context: This is the overridden method ('baz').
+//   num get baz => 42;
+//           ^
+//
+// pkg/front_end/testcases/nnbd/override_checks.dart:16:17: Error: The parameter 'value' of the method 'B2.hest' has type 'num', which does not match the corresponding type, 'num?', in the overridden method, 'B1.hest'.
+// Change to a supertype of 'num?', or, for a covariant parameter, a subtype.
+//   void hest(num value) {} // Error in strong mode and Warning in weak mode.
+//                 ^
+// pkg/front_end/testcases/nnbd/override_checks.dart:10:8: Context: This is the overridden method ('hest').
+//   void hest(num? value) {}
+//        ^
+//
+// pkg/front_end/testcases/nnbd/override_checks.dart:20:18: Error: The type 'int?' doesn't extend 'int'.
+// Try using a different type as argument.
+//   factory C1() = C2<int?>; // Error in strong mode and Warning in weak mode.
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/override_checks.dart:27:27: Error: The constructor function type 'D Function(num)' isn't a subtype of 'D Function(num?)'.
+//  - 'D' is from 'pkg/front_end/testcases/nnbd/override_checks.dart'.
+//   factory D.bar(num? x) = D.foo; // Error in strong mode and Warning in weak mode.
+//                           ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::num> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X>
+    : super core::Object::•()
+    ;
+}
+class B1 extends core::Object {
+  synthetic constructor •() → self::B1
+    : super core::Object::•()
+    ;
+  set bar(core::num? value) → void {}
+  get baz() → core::num
+    return 42;
+  method hest(core::num? value) → void {}
+}
+class B2 extends self::B1 {
+  field core::num bar = 3.14;
+  synthetic constructor •() → self::B2
+    : super self::B1::•()
+    ;
+  get baz() → core::num?
+    return null;
+  method hest(core::num value) → void {}
+}
+class C1 extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  static factory •() → self::C1
+    return invalid-expression "pkg/front_end/testcases/nnbd/override_checks.dart:20:18: Error: The type 'int?' doesn't extend 'int'.
+Try using a different type as argument.
+  factory C1() = C2<int?>; // Error in strong mode and Warning in weak mode.
+                 ^";
+}
+class C2<X extends core::int> extends core::Object implements self::C1 {
+  synthetic constructor •() → self::C2<self::C2::X>
+    : super core::Object::•()
+    ;
+}
+class D extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C2]/*isLegacy*/;
+  constructor foo(core::num x) → self::D
+    : super core::Object::•()
+    ;
+  static factory bar(core::num? x) → self::D
+    return invalid-expression "pkg/front_end/testcases/nnbd/override_checks.dart:27:27: Error: The constructor function type 'D Function(num)' isn't a subtype of 'D Function(num?)'.
+ - 'D' is from 'pkg/front_end/testcases/nnbd/override_checks.dart'.
+  factory D.bar(num? x) = D.foo; // Error in strong mode and Warning in weak mode.
+                          ^";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::C1::•
+  #C2 = constructor-tearoff self::D::bar
+}
diff --git a/pkg/front_end/testcases/nnbd/override_inference.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/override_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..83ec6a1
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/override_inference.dart.weak.modular.expect
@@ -0,0 +1,285 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/override_inference.dart:114:17: Error: Can't infer a type for 'x' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   void method1c(x); // error
+//                 ^
+// pkg/front_end/testcases/nnbd/override_inference.dart:10:8: Context: This is one of the overridden members.
+//   void method1c(int x);
+//        ^^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:62:8: Context: This is one of the overridden members.
+//   void method1c(String x);
+//        ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/override_inference.dart:115:3: Error: Can't infer a return type for 'method1d' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   method1d(); // error
+//   ^^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:11:10: Context: This is one of the overridden members.
+//   String method1d();
+//          ^^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:63:7: Context: This is one of the overridden members.
+//   int method1d();
+//       ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/override_inference.dart:122:8: Error: Can't infer types for 'method5a' as the overridden members don't have a combined signature.
+// Try adding explicit types.
+//   void method5a(x, y); // error
+//        ^^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:18:8: Context: This is one of the overridden members.
+//   void method5a(int x, num y);
+//        ^^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:70:8: Context: This is one of the overridden members.
+//   void method5a(num x, int y);
+//        ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/override_inference.dart:123:32: Error: Can't infer a type for 'z' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   void method5b(num x, num y, [z]); // error
+//                                ^
+// pkg/front_end/testcases/nnbd/override_inference.dart:19:8: Context: This is one of the overridden members.
+//   void method5b(int x, num y);
+//        ^^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:71:8: Context: This is one of the overridden members.
+//   void method5b(num x, int y);
+//        ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/override_inference.dart:130:7: Error: Can't infer a return type for 'getter1c' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   get getter1c; // error
+//       ^^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:26:14: Context: This is one of the overridden members.
+//   String get getter1c;
+//              ^^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:78:11: Context: This is one of the overridden members.
+//   int get getter1c;
+//           ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/override_inference.dart:142:9: Error: Can't infer a type for 'field1c' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   final field1c = null; // error
+//         ^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:40:12: Context: This is one of the overridden members.
+//   int? get field1c;
+//            ^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:92:15: Context: This is one of the overridden members.
+//   double? get field1c;
+//               ^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/override_inference.dart:146:9: Error: Can't infer a type for 'field2c' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   final field2c = null; // error
+//         ^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:44:12: Context: This is one of the overridden members.
+//   void set field2c(int? value);
+//            ^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:96:12: Context: This is one of the overridden members.
+//   void set field2c(double? value);
+//            ^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/override_inference.dart:150:9: Error: Can't infer a type for 'field3c' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   final field3c = null; // error
+//         ^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:48:12: Context: This is one of the overridden members.
+//   int? get field3c;
+//            ^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:100:15: Context: This is one of the overridden members.
+//   double? get field3c;
+//               ^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:52:12: Context: This is one of the overridden members.
+//   void set field3c(Object? value);
+//            ^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:104:12: Context: This is one of the overridden members.
+//   void set field3c(Object? value);
+//            ^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/override_inference.dart:153:7: Error: Can't infer a type for 'field4b' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   var field4b = null; // error
+//       ^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:55:12: Context: This is one of the overridden members.
+//   num? get field4b;
+//            ^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:107:12: Context: This is one of the overridden members.
+//   num? get field4b;
+//            ^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:56:12: Context: This is one of the overridden members.
+//   void set field4b(Object? value);
+//            ^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:108:12: Context: This is one of the overridden members.
+//   void set field4b(Object? value);
+//            ^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/override_inference.dart:136:12: Error: Can't infer a return type for 'setter1c' as the overridden members don't have a combined signature.
+// Try adding an explicit type.
+//   void set setter1c(x); // error
+//            ^^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:33:12: Context: This is one of the overridden members.
+//   void set setter1c(String x);
+//            ^^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:85:12: Context: This is one of the overridden members.
+//   void set setter1c(int x);
+//            ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/override_inference.dart:111:16: Error: Class 'C' inherits multiple members named 'field2c' with incompatible signatures.
+// Try adding a declaration of 'field2c' to 'C'.
+// abstract class C implements A<int>, B<num> {
+//                ^
+// pkg/front_end/testcases/nnbd/override_inference.dart:44:12: Context: This is one of the overridden members.
+//   void set field2c(int? value);
+//            ^^^^^^^
+// pkg/front_end/testcases/nnbd/override_inference.dart:96:12: Context: This is one of the overridden members.
+//   void set field2c(double? value);
+//            ^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+abstract class A<AT extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::AT%>
+    : super core::Object::•()
+    ;
+  abstract method method1a(core::Object x) → core::String;
+  abstract method method1b(core::String x) → core::Object;
+  abstract method method1c(core::int x) → void;
+  abstract method method1d() → core::String;
+  abstract method method2a(core::Object? x) → void;
+  abstract method method2b(dynamic x) → void;
+  abstract method method3a<AT3a extends core::Object? = dynamic>(self::A::method3a::AT3a% x) → void;
+  abstract method method3b<AT3b extends core::Object? = dynamic>(self::A::method3b::AT3b% x) → void;
+  abstract method method4a<AT4a extends core::Object? = dynamic>(self::A::method4a::AT4a% x, covariant-by-class self::A::AT% y) → void;
+  abstract method method4b<AT4b extends core::Object? = dynamic>(self::A::method4b::AT4b% x, covariant-by-class self::A::AT% y) → void;
+  abstract method method5a(core::int x, core::num y) → void;
+  abstract method method5b(core::int x, core::num y) → void;
+  abstract method method6a({core::int x = #C1, core::num y = #C1}) → void;
+  abstract method method6b({core::num y = #C1, core::int x = #C1}) → void;
+  method method7a(core::Object? o, {core::Object? named = #C1}) → core::Object? {}
+  abstract get getter1a() → core::Object;
+  abstract get getter1b() → core::String;
+  abstract get getter1c() → core::String;
+  abstract set getter1d(core::String x) → void;
+  abstract get getter1e() → core::int;
+  abstract set getter1e(core::int x) → void;
+  abstract set setter1a(core::Object x) → void;
+  abstract set setter1b(core::String x) → void;
+  abstract set setter1c(core::String x) → void;
+  abstract get setter1d() → core::String;
+  abstract get setter1e() → core::int;
+  abstract set setter1e(core::int x) → void;
+  abstract get field1a() → core::int?;
+  abstract get field1b() → core::num?;
+  abstract get field1c() → core::int?;
+  abstract set field2a(core::int? value) → void;
+  abstract set field2b(core::num? value) → void;
+  abstract set field2c(core::int? value) → void;
+  abstract get field3a() → core::int?;
+  abstract get field3b() → core::num?;
+  abstract get field3c() → core::int?;
+  abstract set field3a(core::Object? value) → void;
+  abstract set field3b(core::Object? value) → void;
+  abstract set field3c(core::Object? value) → void;
+  abstract get field4a() → core::num?;
+  abstract get field4b() → core::num?;
+  abstract set field4b(core::Object? value) → void;
+}
+abstract class B<BT extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::BT%>
+    : super core::Object::•()
+    ;
+  abstract method method1a(core::String x) → core::Object;
+  abstract method method1b(core::Object x) → core::String;
+  abstract method method1c(core::String x) → void;
+  abstract method method1d() → core::int;
+  abstract method method2a(dynamic x) → void;
+  abstract method method2b(core::Object? x) → void;
+  abstract method method3a<BT3a extends core::Object? = dynamic>(self::B::method3a::BT3a% x) → void;
+  abstract method method3b<BT3b extends core::Object? = dynamic>(self::B::method3b::BT3b% x) → void;
+  abstract method method4a<BT4a extends core::Object? = dynamic>(self::B::method4a::BT4a% x, covariant-by-class self::B::BT% y) → void;
+  abstract method method4b<BT4b extends core::Object? = dynamic>(self::B::method4b::BT4b% x, covariant-by-class self::B::BT% y) → void;
+  abstract method method5a(core::num x, core::int y) → void;
+  abstract method method5b(core::num x, core::int y) → void;
+  abstract method method6a({core::Object x = #C1, core::num y = #C1}) → void;
+  abstract method method6b({core::int x = #C1, core::Object y = #C1}) → void;
+  abstract method method7a(FutureOr<dynamic>o, {FutureOr<dynamic>named = #C1}) → FutureOr<dynamic>;
+  abstract get getter1a() → core::String;
+  abstract get getter1b() → core::Object;
+  abstract get getter1c() → core::int;
+  abstract set getter1d(core::Object x) → void;
+  abstract get getter1e() → core::num;
+  abstract set getter1e(core::Object x) → void;
+  abstract set setter1a(core::String x) → void;
+  abstract set setter1b(core::Object x) → void;
+  abstract set setter1c(core::int x) → void;
+  abstract get setter1d() → core::Object;
+  abstract get setter1e() → core::num;
+  abstract set setter1e(core::Object x) → void;
+  abstract get field1a() → core::num?;
+  abstract get field1b() → core::int?;
+  abstract get field1c() → core::double?;
+  abstract set field2a(core::num? value) → void;
+  abstract set field2b(core::int? value) → void;
+  abstract set field2c(core::double? value) → void;
+  abstract get field3a() → core::num?;
+  abstract get field3b() → core::int?;
+  abstract get field3c() → core::double?;
+  abstract set field3a(core::Object? value) → void;
+  abstract set field3b(core::Object? value) → void;
+  abstract set field3c(core::Object? value) → void;
+  abstract set field4a(core::num? value) → void;
+  abstract get field4b() → core::num?;
+  abstract set field4b(core::Object? value) → void;
+}
+abstract class C extends core::Object implements self::A<core::int>, self::B<core::num> {
+  final field core::int? field1a = null;
+  final field core::int? field1b = null;
+  final field invalid-type field1c = null;
+  final field core::num? field2a = null;
+  final field core::num? field2b = null;
+  final field invalid-type field2c = null;
+  final field core::int? field3a = null;
+  final field core::int? field3b = null;
+  final field invalid-type field3c = null;
+  field core::num? field4a = null;
+  field invalid-type field4b = null;
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  abstract method method1a(core::Object x) → core::String;
+  abstract method method1b(core::Object x) → core::String;
+  abstract method method1c(invalid-type x) → void;
+  abstract method method1d() → invalid-type;
+  abstract method method2a(core::Object? x) → void;
+  abstract method method2b(core::Object? x) → void;
+  abstract method method3a<CT3a extends core::Object? = dynamic>(self::C::method3a::CT3a% x) → void;
+  abstract method method3b<CT3b extends core::Object? = dynamic>(self::C::method3b::CT3b% x, [dynamic y = #C1]) → void;
+  abstract method method4a<CT4a extends core::Object? = dynamic>(self::C::method4a::CT4a% x, covariant-by-class core::num y) → void;
+  abstract method method4b<CT4b extends core::Object? = dynamic>(self::C::method4b::CT4b% x, covariant-by-class core::num y, [dynamic z = #C1]) → void;
+  abstract method method5a(invalid-type x, invalid-type y) → void;
+  abstract method method5b(core::num x, core::num y, [invalid-type z = #C1]) → void;
+  abstract method method6a({core::Object x = #C1, core::num y = #C1}) → void;
+  abstract method method6b({core::int x = #C1, core::Object y = #C1, dynamic z = #C1}) → void;
+  abstract method method7a(core::Object? o, {core::Object? named = #C1}) → core::Object?;
+  abstract get getter1a() → core::String;
+  abstract get getter1b() → core::String;
+  abstract get getter1c() → invalid-type;
+  abstract get getter1d() → core::Object;
+  abstract get getter1e() → core::int;
+  abstract set setter1a(core::Object x) → void;
+  abstract set setter1b(core::Object x) → void;
+  abstract set setter1c(invalid-type x) → void;
+  abstract set setter1d(core::String x) → void;
+  abstract set setter1e(core::Object x) → void;
+  abstract member-signature set getter1d(core::Object x) → void; -> self::B::getter1d
+  abstract member-signature set getter1e(core::Object x) → void; -> self::B::getter1e
+  abstract member-signature set field2a(core::num? value) → void; -> self::B::field2a
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/parenthesized_stop_shorting.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/parenthesized_stop_shorting.dart.weak.modular.expect
new file mode 100644
index 0000000..bb556eb
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/parenthesized_stop_shorting.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  get foo() → core::int
+    return throw 42;
+}
+static method bar(core::int x) → dynamic {}
+static method test(self::A? a) → dynamic {
+  self::bar((let final self::A? #t1 = a in #t1 == null ?{core::int?} null : #t1{self::A}.{self::A::foo}{core::int})!);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/platform_definite_assignment/main.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/platform_definite_assignment/main.dart.weak.modular.expect
new file mode 100644
index 0000000..4384943
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/platform_definite_assignment/main.dart.weak.modular.expect
@@ -0,0 +1,124 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:test" as test;
+import "dart:core" as core;
+
+import "dart:test";
+
+static method main() → dynamic {
+  test::Class<core::num>? c;
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/platform_definite_assignment/patch_lib.dart:15:5: Error: Non-nullable variable 'k' must be assigned before it can be used.
+//     k;
+//     ^
+//
+// pkg/front_end/testcases/nnbd/platform_definite_assignment/patch_lib.dart:22:12: Error: Non-nullable variable 'k' must be assigned before it can be used.
+//     return k;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/platform_definite_assignment/patch_lib.dart:28:12: Error: Non-nullable variable 'k' must be assigned before it can be used.
+//     return k;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/platform_definite_assignment/patch_lib.dart:36:10: Error: Non-nullable variable 'k' must be assigned before it can be used.
+//   return k;
+//          ^
+//
+// pkg/front_end/testcases/nnbd/platform_definite_assignment/patch_lib.dart:42:10: Error: Non-nullable variable 'k' must be assigned before it can be used.
+//   return k;
+//          ^
+//
+// pkg/front_end/testcases/nnbd/platform_definite_assignment/origin_lib.dart:17:5: Error: Non-nullable variable 'k' must be assigned before it can be used.
+//     k;
+//     ^
+//
+// pkg/front_end/testcases/nnbd/platform_definite_assignment/origin_lib.dart:25:12: Error: Non-nullable variable 'k' must be assigned before it can be used.
+//     return k;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/platform_definite_assignment/origin_lib.dart:34:10: Error: Non-nullable variable 'k' must be assigned before it can be used.
+//   return k;
+//          ^
+//
+import self as test;
+import "dart:_internal" as _in;
+import "dart:core" as core;
+
+import "dart:_internal";
+
+@#C1
+class Class<T extends core::num> extends core::Object /*hasConstConstructor*/  {
+  final field core::int a;
+  final field test::Class::T b;
+  const constructor constConstructor(core::int a, test::Class::T b) → test::Class<test::Class::T>
+    : test::Class::a = a, test::Class::b = b, super core::Object::•()
+    ;
+  constructor constructor(core::int a, test::Class::T b) → test::Class<test::Class::T>
+    : test::Class::a = a, test::Class::b = b, super core::Object::•() {
+    core::int k;
+    invalid-expression "pkg/front_end/testcases/nnbd/platform_definite_assignment/origin_lib.dart:17:5: Error: Non-nullable variable 'k' must be assigned before it can be used.
+    k;
+    ^" in k;
+  }
+  @#C1
+  constructor patchedConstructor(core::int i, test::Class::T j) → test::Class<test::Class::T>
+    : test::Class::a = i, test::Class::b = j, super core::Object::•() {
+    core::int k;
+    invalid-expression "pkg/front_end/testcases/nnbd/platform_definite_assignment/patch_lib.dart:15:5: Error: Non-nullable variable 'k' must be assigned before it can be used.
+    k;
+    ^" in k;
+  }
+  method method(core::int a) → core::int {
+    core::int k;
+    core::int j = a;
+    return invalid-expression "pkg/front_end/testcases/nnbd/platform_definite_assignment/origin_lib.dart:25:12: Error: Non-nullable variable 'k' must be assigned before it can be used.
+    return k;
+           ^" in k;
+  }
+  @#C1
+  method /* from org-dartlang-testcase:///patch_lib.dart */ patchedMethod(core::int i) → core::int {
+    core::int k;
+    core::int j = i;
+    return invalid-expression "pkg/front_end/testcases/nnbd/platform_definite_assignment/patch_lib.dart:22:12: Error: Non-nullable variable 'k' must be assigned before it can be used.
+    return k;
+           ^" in k;
+  }
+  method /* from org-dartlang-testcase:///patch_lib.dart */ _injectedMethod(core::int i) → core::int {
+    core::int k;
+    core::int j = i;
+    return invalid-expression "pkg/front_end/testcases/nnbd/platform_definite_assignment/patch_lib.dart:28:12: Error: Non-nullable variable 'k' must be assigned before it can be used.
+    return k;
+           ^" in k;
+  }
+}
+static method method(core::int a) → core::int {
+  core::int k;
+  core::int j = a;
+  return invalid-expression "pkg/front_end/testcases/nnbd/platform_definite_assignment/origin_lib.dart:34:10: Error: Non-nullable variable 'k' must be assigned before it can be used.
+  return k;
+         ^" in k;
+}
+@#C1
+static method /* from org-dartlang-testcase:///patch_lib.dart */ patchedMethod(core::int i) → core::int {
+  core::int k;
+  core::int j = i;
+  return invalid-expression "pkg/front_end/testcases/nnbd/platform_definite_assignment/patch_lib.dart:36:10: Error: Non-nullable variable 'k' must be assigned before it can be used.
+  return k;
+         ^" in k;
+}
+static method /* from org-dartlang-testcase:///patch_lib.dart */ _injectedMethod(core::int i) → core::int {
+  core::int k;
+  core::int j = i;
+  return invalid-expression "pkg/front_end/testcases/nnbd/platform_definite_assignment/patch_lib.dart:42:10: Error: Non-nullable variable 'k' must be assigned before it can be used.
+  return k;
+         ^" in k;
+}
+
+constants  {
+  #C1 = _in::_Patch {}
+}
diff --git a/pkg/front_end/testcases/nnbd/platform_nonnullable_fields/main.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/platform_nonnullable_fields/main.dart.weak.modular.expect
new file mode 100644
index 0000000..8aa11f6
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/platform_nonnullable_fields/main.dart.weak.modular.expect
@@ -0,0 +1,58 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:test" as test;
+
+import "dart:test";
+
+static method main() → dynamic {
+  test::Class1? c1;
+  test::Class2? c2;
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/platform_nonnullable_fields/patch_lib2.dart:32:14: Error: Field 'staticField' should be initialized because its type 'int' doesn't allow null.
+//   static int staticField;
+//              ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/platform_nonnullable_fields/patch_lib2.dart:30:7: Error: Field 'field' should be initialized because its type 'int' doesn't allow null.
+//   int field;
+//       ^^^^^
+//
+// pkg/front_end/testcases/nnbd/platform_nonnullable_fields/origin_lib.dart:8:3: Error: This constructor should initialize field 'field' because its type 'int' doesn't allow null.
+//   Class2.constructor1();
+//   ^
+// pkg/front_end/testcases/nnbd/platform_nonnullable_fields/patch_lib2.dart:37:7: Context: 'field' is defined here.
+//   int field;
+//       ^^^^^
+//
+import self as test;
+import "dart:_internal" as _in;
+import "dart:core" as core;
+
+import "dart:_internal";
+
+@#C1
+class Class1 extends core::Object {
+  field core::int field = null /* from org-dartlang-testcase:///patch_lib2.dart */;
+  static field core::int staticField = null /* from org-dartlang-testcase:///patch_lib2.dart */;
+  synthetic constructor •() → test::Class1
+    : super core::Object::•()
+    ;
+}
+@#C1
+class Class2 extends core::Object {
+  field core::int field /* from org-dartlang-testcase:///patch_lib2.dart */;
+  constructor constructor2(core::int field) → test::Class2
+    : test::Class2::field = field, super core::Object::•()
+    ;
+  constructor constructor1() → test::Class2
+    : test::Class2::field = null, super core::Object::•()
+    ;
+}
+
+constants  {
+  #C1 = _in::_Patch {}
+}
diff --git a/pkg/front_end/testcases/nnbd/platform_optional_parameters/main.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/platform_optional_parameters/main.dart.weak.modular.expect
new file mode 100644
index 0000000..2d71c44
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/platform_optional_parameters/main.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:test" as test;
+
+import "dart:test";
+
+static method main() → dynamic {
+  test::Class? c = new test::Class::•();
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/platform_optional_parameters/patch_lib.dart:11:27: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   void patchedMethod([int i]) {}
+//                           ^
+//
+// pkg/front_end/testcases/nnbd/platform_optional_parameters/patch_lib.dart:13:29: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   void _injectedMethod([int i]) {}
+//                             ^
+//
+// pkg/front_end/testcases/nnbd/platform_optional_parameters/patch_lib.dart:17:25: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// void patchedMethod([int i]) {}
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/platform_optional_parameters/patch_lib.dart:19:27: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// void _injectedMethod([int i]) {}
+//                           ^
+//
+// pkg/front_end/testcases/nnbd/platform_optional_parameters/origin_lib.dart:6:20: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   void method([int i]) {}
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/platform_optional_parameters/origin_lib.dart:11:18: Error: The parameter 'i' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// void method([int i]) {}
+//                  ^
+//
+import self as test;
+import "dart:_internal" as _in;
+import "dart:core" as core;
+
+import "dart:_internal";
+
+@#C1
+class Class extends core::Object {
+  synthetic constructor •() → test::Class
+    : super core::Object::•()
+    ;
+  method method([core::int i = #C2]) → void {}
+  @#C1
+  method /* from org-dartlang-testcase:///patch_lib.dart */ patchedMethod([core::int i = #C2]) → void {}
+  method /* from org-dartlang-testcase:///patch_lib.dart */ _injectedMethod([core::int i = #C2]) → void {}
+}
+static method method([core::int i = #C2]) → void {}
+@#C1
+static method /* from org-dartlang-testcase:///patch_lib.dart */ patchedMethod([core::int i = #C2]) → void {}
+static method /* from org-dartlang-testcase:///patch_lib.dart */ _injectedMethod([core::int i = #C2]) → void {}
+
+constants  {
+  #C1 = _in::_Patch {}
+  #C2 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart.weak.modular.expect
new file mode 100644
index 0000000..752b8a6
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart.weak.modular.expect
@@ -0,0 +1,258 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:65:9: Error: Constant evaluation error:
+//   const Class<num>(''); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:16:46: Context: Expected constant '""' to be of type 'num', but was of type 'String'.
+//   const Class(dynamic value) : field = value as T;
+//                                              ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:66:9: Error: Constant evaluation error:
+//   const Class<int>(0.5); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:16:46: Context: Expected constant '0.5' to be of type 'int', but was of type 'double'.
+//   const Class(dynamic value) : field = value as T;
+//                                              ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:67:9: Error: Constant evaluation error:
+//   const Class<String>(0); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:16:46: Context: Expected constant '0' to be of type 'String', but was of type 'int'.
+//   const Class(dynamic value) : field = value as T;
+//                                              ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:68:9: Error: Constant evaluation error:
+//   const ClassWithBound<double>(); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:22:42: Context: Expected constant '3' to be of type 'double', but was of type 'int'.
+//   const ClassWithBound() : field = three as T;
+//                                          ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:69:9: Error: Constant evaluation error:
+//   const ClassWithBound<double>.withValue(0); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:24:65: Context: Expected constant '0' to be of type 'double', but was of type 'int'.
+//   const ClassWithBound.withValue(dynamic value) : field = value as T;
+//                                                                 ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:70:9: Error: Constant evaluation error:
+//   const ClassWithBound<double>.withValue(three); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:24:65: Context: Expected constant '3' to be of type 'double', but was of type 'int'.
+//   const ClassWithBound.withValue(dynamic value) : field = value as T;
+//                                                                 ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:71:9: Error: Constant evaluation error:
+//   const ClassWithBound<num>.withValue(''); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:24:65: Context: Expected constant '""' to be of type 'num', but was of type 'String'.
+//   const ClassWithBound.withValue(dynamic value) : field = value as T;
+//                                                                 ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:72:9: Error: Constant evaluation error:
+//   const ClassWithList(0); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:30:54: Context: Expected constant '0' to be of type 'List<dynamic>', but was of type 'int'.
+//  - 'List' is from 'dart:core'.
+//   const ClassWithList(dynamic value) : field = value as List<T>;
+//                                                      ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:73:9: Error: Constant evaluation error:
+//   const ClassWithList<num>(<String>['']); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:30:54: Context: Expected constant '<String>[""]' to be of type 'List<num>', but was of type 'List<String>'.
+//  - 'List' is from 'dart:core'.
+//   const ClassWithList(dynamic value) : field = value as List<T>;
+//                                                      ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:74:9: Error: Constant evaluation error:
+//   const ClassWithList<int>(<num>[0]); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:30:54: Context: Expected constant '<num>[0]' to be of type 'List<int>', but was of type 'List<num>'.
+//  - 'List' is from 'dart:core'.
+//   const ClassWithList(dynamic value) : field = value as List<T>;
+//                                                      ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:75:9: Error: Constant evaluation error:
+//   const ClassWithList<String>(<int>[0]); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:30:54: Context: Expected constant '<int>[0]' to be of type 'List<String>', but was of type 'List<int>'.
+//  - 'List' is from 'dart:core'.
+//   const ClassWithList(dynamic value) : field = value as List<T>;
+//                                                      ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:76:9: Error: Constant evaluation error:
+//   const ClassWithFunction(0); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:36:58: Context: Expected constant '0' to be of type 'dynamic Function(dynamic)', but was of type 'int'.
+//   const ClassWithFunction(dynamic value) : field = value as T Function(T);
+//                                                          ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:77:9: Error: Constant evaluation error:
+//   const ClassWithFunction(intFunction); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:36:58: Context: Expected constant 'intFunction' to be of type 'dynamic Function(dynamic)', but was of type 'int Function(int)'.
+//   const ClassWithFunction(dynamic value) : field = value as T Function(T);
+//                                                          ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:78:9: Error: Constant evaluation error:
+//   const ClassWithFunction<Object>(intFunction); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:36:58: Context: Expected constant 'intFunction' to be of type 'Object Function(Object)', but was of type 'int Function(int)'.
+//  - 'Object' is from 'dart:core'.
+//   const ClassWithFunction(dynamic value) : field = value as T Function(T);
+//                                                          ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:79:9: Error: Constant evaluation error:
+//   const ClassWithFunction<void>(intFunction); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:36:58: Context: Expected constant 'intFunction' to be of type 'void Function(void)', but was of type 'int Function(int)'.
+//   const ClassWithFunction(dynamic value) : field = value as T Function(T);
+//                                                          ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:80:9: Error: Constant evaluation error:
+//   const ClassWithFunction<num>(intFunction); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:36:58: Context: Expected constant 'intFunction' to be of type 'num Function(num)', but was of type 'int Function(int)'.
+//   const ClassWithFunction(dynamic value) : field = value as T Function(T);
+//                                                          ^
+//
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:81:9: Error: Constant evaluation error:
+//   const ClassWithFunction<int>(idFunction); // error
+//         ^
+// pkg/front_end/testcases/nnbd/potentially_constant_type_as.dart:36:58: Context: Expected constant 'idFunction' to be of type 'int Function(int)', but was of type 'T Function<T>(T)'.
+//   const ClassWithFunction(dynamic value) : field = value as T Function(T);
+//                                                          ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field self::Class::T% field;
+  const constructor •(dynamic value) → self::Class<self::Class::T%>
+    : self::Class::field = value as{ForNonNullableByDefault} self::Class::T%, super core::Object::•()
+    ;
+}
+class ClassWithBound<T extends core::num> extends core::Object /*hasConstConstructor*/  {
+  final field self::ClassWithBound::T field;
+  const constructor •() → self::ClassWithBound<self::ClassWithBound::T>
+    : self::ClassWithBound::field = #C1 as{ForNonNullableByDefault} self::ClassWithBound::T, super core::Object::•()
+    ;
+  const constructor withValue(dynamic value) → self::ClassWithBound<self::ClassWithBound::T>
+    : self::ClassWithBound::field = value as{ForNonNullableByDefault} self::ClassWithBound::T, super core::Object::•()
+    ;
+}
+class ClassWithList<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field core::List<self::ClassWithList::T%> field;
+  const constructor •(dynamic value) → self::ClassWithList<self::ClassWithList::T%>
+    : self::ClassWithList::field = value as{ForNonNullableByDefault} core::List<self::ClassWithList::T%>, super core::Object::•()
+    ;
+}
+class ClassWithFunction<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field (self::ClassWithFunction::T%) → self::ClassWithFunction::T% field;
+  const constructor •(dynamic value) → self::ClassWithFunction<self::ClassWithFunction::T%>
+    : self::ClassWithFunction::field = value as{ForNonNullableByDefault} (self::ClassWithFunction::T%) → self::ClassWithFunction::T%, super core::Object::•()
+    ;
+}
+static const field core::num three = #C1;
+static const field (core::int) → core::int idAsIntFunction = #C3;
+static method dynamicFunction(dynamic d) → dynamic
+  return d;
+static method objectFunction(core::Object? o) → core::Object?
+  return o;
+static method intFunction(core::int i) → core::int
+  return i;
+static method idFunction<T extends core::Object? = dynamic>(self::idFunction::T% t) → self::idFunction::T%
+  return t;
+static method main() → void {
+  #C5;
+  #C6;
+  #C7;
+  #C9;
+  #C10;
+  #C11;
+  #C10;
+  #C13;
+  #C15;
+  #C17;
+  #C18;
+  #C20;
+  #C22;
+  #C23;
+  #C25;
+  #C26;
+  #C28;
+  #C29;
+}
+static method weakMode() → dynamic {
+  #C30;
+}
+static method errors() → dynamic {
+  invalid-expression "Expected constant '\"\"' to be of type 'num', but was of type 'String'.";
+  invalid-expression "Expected constant '0.5' to be of type 'int', but was of type 'double'.";
+  invalid-expression "Expected constant '0' to be of type 'String', but was of type 'int'.";
+  invalid-expression "Expected constant '3' to be of type 'double', but was of type 'int'.";
+  invalid-expression "Expected constant '0' to be of type 'double', but was of type 'int'.";
+  invalid-expression "Expected constant '3' to be of type 'double', but was of type 'int'.";
+  invalid-expression "Expected constant '\"\"' to be of type 'num', but was of type 'String'.";
+  invalid-expression "Expected constant '0' to be of type 'List<dynamic>', but was of type 'int'.
+ - 'List' is from 'dart:core'.";
+  invalid-expression "Expected constant '<String>[\"\"]' to be of type 'List<num>', but was of type 'List<String>'.
+ - 'List' is from 'dart:core'.";
+  invalid-expression "Expected constant '<num>[0]' to be of type 'List<int>', but was of type 'List<num>'.
+ - 'List' is from 'dart:core'.";
+  invalid-expression "Expected constant '<int>[0]' to be of type 'List<String>', but was of type 'List<int>'.
+ - 'List' is from 'dart:core'.";
+  invalid-expression "Expected constant '0' to be of type 'dynamic Function(dynamic)', but was of type 'int'.";
+  invalid-expression "Expected constant 'intFunction' to be of type 'dynamic Function(dynamic)', but was of type 'int Function(int)'.";
+  invalid-expression "Expected constant 'intFunction' to be of type 'Object Function(Object)', but was of type 'int Function(int)'.
+ - 'Object' is from 'dart:core'.";
+  invalid-expression "Expected constant 'intFunction' to be of type 'void Function(void)', but was of type 'int Function(int)'.";
+  invalid-expression "Expected constant 'intFunction' to be of type 'num Function(num)', but was of type 'int Function(int)'.";
+  invalid-expression "Expected constant 'idFunction' to be of type 'int Function(int)', but was of type 'T Function<T>(T)'.";
+}
+
+constants  {
+  #C1 = 3
+  #C2 = static-tearoff self::idFunction
+  #C3 = instantiation #C2 <core::int*>
+  #C4 = 0
+  #C5 = self::Class<dynamic> {field:#C4}
+  #C6 = self::Class<core::num*> {field:#C4}
+  #C7 = self::Class<core::int*> {field:#C4}
+  #C8 = ""
+  #C9 = self::Class<core::String*> {field:#C8}
+  #C10 = self::ClassWithBound<core::int*> {field:#C1}
+  #C11 = self::ClassWithBound<core::int*> {field:#C4}
+  #C12 = 0.5
+  #C13 = self::ClassWithBound<core::double*> {field:#C12}
+  #C14 = <dynamic>[]
+  #C15 = self::ClassWithList<dynamic> {field:#C14}
+  #C16 = <core::int*>[#C4]
+  #C17 = self::ClassWithList<core::num*> {field:#C16}
+  #C18 = self::ClassWithList<core::int*> {field:#C16}
+  #C19 = <core::String*>[#C8]
+  #C20 = self::ClassWithList<core::String*> {field:#C19}
+  #C21 = static-tearoff self::dynamicFunction
+  #C22 = self::ClassWithFunction<dynamic> {field:#C21}
+  #C23 = self::ClassWithFunction<core::Object?> {field:#C21}
+  #C24 = static-tearoff self::objectFunction
+  #C25 = self::ClassWithFunction<dynamic> {field:#C24}
+  #C26 = self::ClassWithFunction<void> {field:#C24}
+  #C27 = static-tearoff self::intFunction
+  #C28 = self::ClassWithFunction<core::int*> {field:#C27}
+  #C29 = self::ClassWithFunction<core::int*> {field:#C3}
+  #C30 = self::ClassWithFunction<core::Object*> {field:#C24}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///potentially_constant_type_as.dart:
+- Class. (from org-dartlang-testcase:///potentially_constant_type_as.dart:16:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- ClassWithBound. (from org-dartlang-testcase:///potentially_constant_type_as.dart:22:9)
+- ClassWithBound.withValue (from org-dartlang-testcase:///potentially_constant_type_as.dart:24:9)
+- ClassWithList. (from org-dartlang-testcase:///potentially_constant_type_as.dart:30:9)
+- ClassWithFunction. (from org-dartlang-testcase:///potentially_constant_type_as.dart:36:9)
diff --git a/pkg/front_end/testcases/nnbd/potentially_constant_type_is.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/potentially_constant_type_is.dart.weak.modular.expect
new file mode 100644
index 0000000..3b6c8a8
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/potentially_constant_type_is.dart.weak.modular.expect
@@ -0,0 +1,126 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Class<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field core::bool field;
+  const constructor •(dynamic value) → self::Class<self::Class::T%>
+    : self::Class::field = value is{ForNonNullableByDefault} self::Class::T%, super core::Object::•()
+    ;
+}
+class ClassWithBound<T extends core::num> extends core::Object /*hasConstConstructor*/  {
+  final field core::bool field;
+  const constructor •() → self::ClassWithBound<self::ClassWithBound::T>
+    : self::ClassWithBound::field = #C1 is{ForNonNullableByDefault} self::ClassWithBound::T, super core::Object::•()
+    ;
+  const constructor withValue(dynamic value) → self::ClassWithBound<self::ClassWithBound::T>
+    : self::ClassWithBound::field = value is{ForNonNullableByDefault} self::ClassWithBound::T, super core::Object::•()
+    ;
+}
+class ClassWithList<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field core::bool field;
+  const constructor •(dynamic value) → self::ClassWithList<self::ClassWithList::T%>
+    : self::ClassWithList::field = value is{ForNonNullableByDefault} core::List<self::ClassWithList::T%>, super core::Object::•()
+    ;
+}
+class ClassWithFunction<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field core::bool field;
+  const constructor •(dynamic value) → self::ClassWithFunction<self::ClassWithFunction::T%>
+    : self::ClassWithFunction::field = value is{ForNonNullableByDefault} (self::ClassWithFunction::T%) → self::ClassWithFunction::T%, super core::Object::•()
+    ;
+}
+static const field core::num three = #C1;
+static const field (core::int) → core::int idAsIntFunction = #C3;
+static method dynamicFunction(dynamic d) → dynamic
+  return d;
+static method objectFunction(core::Object? o) → core::Object?
+  return o;
+static method intFunction(core::int i) → core::int
+  return i;
+static method idFunction<T extends core::Object? = dynamic>(self::idFunction::T% t) → self::idFunction::T%
+  return t;
+static method main() → void {
+  #C5;
+  #C6;
+  #C7;
+  #C8;
+  #C9;
+  #C9;
+  #C9;
+  #C10;
+  #C11;
+  #C12;
+  #C13;
+  #C14;
+  #C15;
+  #C16;
+  #C15;
+  #C17;
+  #C18;
+  #C18;
+  #C19;
+  #C21;
+  #C22;
+  #C23;
+  #C24;
+  #C24;
+  #C24;
+  #C25;
+  #C26;
+  #C27;
+  #C28;
+  #C29;
+  #C30;
+  #C30;
+  #C31;
+  #C32;
+  #C33;
+  #C34;
+}
+
+constants  {
+  #C1 = 3
+  #C2 = static-tearoff self::idFunction
+  #C3 = instantiation #C2 <core::int*>
+  #C4 = true
+  #C5 = self::Class<dynamic> {field:#C4}
+  #C6 = self::Class<core::num*> {field:#C4}
+  #C7 = self::Class<core::int*> {field:#C4}
+  #C8 = self::Class<core::String*> {field:#C4}
+  #C9 = self::ClassWithBound<core::int*> {field:#C4}
+  #C10 = self::ClassWithBound<core::double*> {field:#C4}
+  #C11 = self::ClassWithList<dynamic> {field:#C4}
+  #C12 = self::ClassWithList<core::num*> {field:#C4}
+  #C13 = self::ClassWithList<core::int*> {field:#C4}
+  #C14 = self::ClassWithList<core::String*> {field:#C4}
+  #C15 = self::ClassWithFunction<dynamic> {field:#C4}
+  #C16 = self::ClassWithFunction<core::Object?> {field:#C4}
+  #C17 = self::ClassWithFunction<void> {field:#C4}
+  #C18 = self::ClassWithFunction<core::int*> {field:#C4}
+  #C19 = self::ClassWithFunction<core::Object*> {field:#C4}
+  #C20 = false
+  #C21 = self::Class<core::num*> {field:#C20}
+  #C22 = self::Class<core::int*> {field:#C20}
+  #C23 = self::Class<core::String*> {field:#C20}
+  #C24 = self::ClassWithBound<core::double*> {field:#C20}
+  #C25 = self::ClassWithBound<core::num*> {field:#C20}
+  #C26 = self::ClassWithList<dynamic> {field:#C20}
+  #C27 = self::ClassWithList<core::num*> {field:#C20}
+  #C28 = self::ClassWithList<core::int*> {field:#C20}
+  #C29 = self::ClassWithList<core::String*> {field:#C20}
+  #C30 = self::ClassWithFunction<dynamic> {field:#C20}
+  #C31 = self::ClassWithFunction<core::Object*> {field:#C20}
+  #C32 = self::ClassWithFunction<void> {field:#C20}
+  #C33 = self::ClassWithFunction<core::num*> {field:#C20}
+  #C34 = self::ClassWithFunction<core::int*> {field:#C20}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///potentially_constant_type_is.dart:
+- Class. (from org-dartlang-testcase:///potentially_constant_type_is.dart:16:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- ClassWithBound. (from org-dartlang-testcase:///potentially_constant_type_is.dart:22:9)
+- ClassWithBound.withValue (from org-dartlang-testcase:///potentially_constant_type_is.dart:24:9)
+- ClassWithList. (from org-dartlang-testcase:///potentially_constant_type_is.dart:30:9)
+- ClassWithFunction. (from org-dartlang-testcase:///potentially_constant_type_is.dart:36:9)
diff --git a/pkg/front_end/testcases/nnbd/potentially_non_nullable_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/potentially_non_nullable_field.dart.weak.modular.expect
new file mode 100644
index 0000000..f8836ef
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/potentially_non_nullable_field.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/potentially_non_nullable_field.dart:8:5: Error: Field 'x' should be initialized because its type 'int' doesn't allow null.
+// int x; // Error.
+//     ^
+//
+// pkg/front_end/testcases/nnbd/potentially_non_nullable_field.dart:13:14: Error: Field 'x' should be initialized because its type 'int' doesn't allow null.
+//   static int x; // Error.
+//              ^
+//
+// pkg/front_end/testcases/nnbd/potentially_non_nullable_field.dart:17:7: Error: Field 'lx' should be initialized because its type 'int' doesn't allow null.
+//   int lx; // Error.
+//       ^^
+//
+// pkg/front_end/testcases/nnbd/potentially_non_nullable_field.dart:23:5: Error: Field 'lt' should be initialized because its type 'T' doesn't allow null.
+//   T lt; // Error.
+//     ^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object?> extends core::Object {
+  static field core::int x = null;
+  static field core::int? y = null;
+  late static field core::int z;
+  field core::int lx = null;
+  field core::int? ly = null;
+  late field core::int? lz;
+  field core::int lv;
+  field core::int lu;
+  covariant-by-class field self::A::T% lt = null;
+  covariant-by-class field self::A::T? ls = null;
+  late covariant-by-class field self::A::T% lr;
+  covariant-by-class field self::A::T% lp;
+  covariant-by-class field self::A::T% lq;
+  constructor •(core::int lv, self::A::T% lp, self::A::T% t) → self::A<self::A::T%>
+    : self::A::lv = lv, self::A::lp = lp, self::A::lu = 42, self::A::lq = t, super core::Object::•()
+    ;
+}
+static field core::int x;
+static field core::int? y;
+late static field core::int z;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/potentially_nullable_access.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/potentially_nullable_access.dart.weak.modular.expect
new file mode 100644
index 0000000..939fe87
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/potentially_nullable_access.dart.weak.modular.expect
@@ -0,0 +1,828 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:37:34: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+// var topLevelBinary = nullableInt + 0;
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:38:21: Error: Operator 'unary-' cannot be called on 'int?' because it is potentially null.
+// var topLevelUnary = -nullableInt;
+//                     ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:39:35: Error: Operator '[]' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+//  - 'Map' is from 'dart:core'.
+// var topLevelIndexGet = nullableMap[0];
+//                                   ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:40:35: Error: Operator '[]=' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+//  - 'Map' is from 'dart:core'.
+// var topLevelIndexSet = nullableMap[0] = 1;
+//                                   ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:41:38: Error: Operator '[]' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+//  - 'Map' is from 'dart:core'.
+// var topLevelIndexGetSet = nullableMap[0] += 1;
+//                                      ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:41:38: Error: Operator '[]=' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+//  - 'Map' is from 'dart:core'.
+// var topLevelIndexGetSet = nullableMap[0] += 1;
+//                                      ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:42:41: Error: Property 'property' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+// var topLevelPropertyGet = nullableClass.property;
+//                                         ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:43:41: Error: Property 'property' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+// var topLevelPropertySet = nullableClass.property = 1;
+//                                         ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:44:44: Error: Property 'property' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+// var topLevelPropertyGetSet = nullableClass.property += 1;
+//                                            ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:45:46: Error: Method 'method' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?. instead.
+// var topLevelMethodInvocation = nullableClass.method();
+//                                              ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:46:43: Error: Property 'method' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+// var topLevelMethodTearOff = nullableClass.method;
+//                                           ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:47:52: Error: Can't use an expression of type 'Function?' as a function because it's potentially null.
+//  - 'Function' is from 'dart:core'.
+// Try calling using ?.call instead.
+// var topLevelFunctionImplicitCall = nullableFunction();
+//                                                    ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:48:53: Error: Method 'call' cannot be called on 'Function?' because it is potentially null.
+//  - 'Function' is from 'dart:core'.
+// Try calling using ?. instead.
+// var topLevelFunctionExplicitCall = nullableFunction.call();
+//                                                     ^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:49:48: Error: Property 'call' cannot be accessed on 'Function?' because it is potentially null.
+//  - 'Function' is from 'dart:core'.
+// Try accessing using ?. instead.
+// var topLevelFunctionTearOff = nullableFunction.call;
+//                                                ^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:50:60: Error: Can't use an expression of type 'void Function()?' as a function because it's potentially null.
+// Try calling using ?.call instead.
+// var topLevelFunctionTypeImplicitCall = nullableFunctionType();
+//                                                            ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:51:61: Error: Method 'call' cannot be called on 'void Function()?' because it is potentially null.
+// Try calling using ?. instead.
+// var topLevelFunctionTypeExplicitCall = nullableFunctionType.call();
+//                                                             ^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:52:56: Error: Property 'call' cannot be accessed on 'void Function()?' because it is potentially null.
+// Try accessing using ?. instead.
+// var topLevelFunctionTypeTearOff = nullableFunctionType.call;
+//                                                        ^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:53:43: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?.call instead.
+// var topLevelFunctionField = nullableClass.functionField();
+//                                           ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:54:47: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?.call instead.
+// var topLevelFunctionTypeField = nullableClass.functionTypeField();
+//                                               ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:55:44: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?.call instead.
+// var topLevelFunctionGetter = nullableClass.functionGetter();
+//                                            ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:56:48: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?.call instead.
+// var topLevelFunctionTypeGetter = nullableClass.functionTypeGetter();
+//                                                ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:58:45: Error: Operator '+' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// var topLevelExtensionBinary = nullableClass + 0;
+//                                             ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:59:30: Error: Operator 'unary-' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// var topLevelExtensionUnary = -nullableClass;
+//                              ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:60:46: Error: Operator '[]' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// var topLevelExtensionIndexGet = nullableClass[0];
+//                                              ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:61:46: Error: Operator '[]=' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// var topLevelExtensionIndexSet = nullableClass[0] = 1;
+//                                              ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:62:49: Error: Operator '[]' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// var topLevelExtensionIndexGetSet = nullableClass[0] += 1;
+//                                                 ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:62:49: Error: Operator '[]=' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// var topLevelExtensionIndexGetSet = nullableClass[0] += 1;
+//                                                 ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:63:50: Error: Property 'extensionProperty' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+// var topLevelExtensionPropertyGet = nullableClass.extensionProperty;
+//                                                  ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:64:50: Error: Property 'extensionProperty' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+// var topLevelExtensionPropertySet = nullableClass.extensionProperty = 1;
+//                                                  ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:65:53: Error: Property 'extensionProperty' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+// var topLevelExtensionPropertyGetSet = nullableClass.extensionProperty += 1;
+//                                                     ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:66:55: Error: Method 'extensionMethod' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?. instead.
+// var topLevelExtensionMethodInvocation = nullableClass.extensionMethod();
+//                                                       ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:67:52: Error: Property 'extensionMethod' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+// var topLevelExtensionMethodTearOff = nullableClass.extensionMethod;
+//                                                    ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:68:62: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?.call instead.
+// var topLevelExtensionFunctionTypeImplicitCall = nullableClass();
+//                                                              ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:69:63: Error: Method 'call' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?. instead.
+// var topLevelExtensionFunctionTypeExplicitCall = nullableClass.call();
+//                                                               ^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:70:58: Error: Property 'call' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+// var topLevelExtensionFunctionTypeTearOff = nullableClass.call;
+//                                                          ^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:71:53: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?.call instead.
+// var topLevelExtensionFunctionGetter = nullableClass.extensionFunctionGetter();
+//                                                     ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:73:19: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?.call instead.
+//     nullableClass.extensionFunctionTypeGetter();
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:76:33: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+//   var localBinary = nullableInt + 0;
+//                                 ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:77:20: Error: Operator 'unary-' cannot be called on 'int?' because it is potentially null.
+//   var localUnary = -nullableInt;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:78:34: Error: Operator '[]' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+//  - 'Map' is from 'dart:core'.
+//   var localIndexGet = nullableMap[0];
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:79:34: Error: Operator '[]=' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+//  - 'Map' is from 'dart:core'.
+//   var localIndexSet = nullableMap[0] = 1;
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:80:37: Error: Operator '[]' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+//  - 'Map' is from 'dart:core'.
+//   var localIndexGetSet = nullableMap[0] += 1;
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:80:37: Error: Operator '[]=' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+//  - 'Map' is from 'dart:core'.
+//   var localIndexGetSet = nullableMap[0] += 1;
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:81:40: Error: Property 'property' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+//   var localPropertyGet = nullableClass.property;
+//                                        ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:82:40: Error: Property 'property' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+//   var localPropertySet = nullableClass.property = 1;
+//                                        ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:83:43: Error: Property 'property' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+//   var localPropertyGetSet = nullableClass.property += 1;
+//                                           ^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:84:45: Error: Method 'method' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?. instead.
+//   var localMethodInvocation = nullableClass.method();
+//                                             ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:85:42: Error: Property 'method' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+//   var localMethodTearOff = nullableClass.method;
+//                                          ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:86:51: Error: Can't use an expression of type 'Function?' as a function because it's potentially null.
+//  - 'Function' is from 'dart:core'.
+// Try calling using ?.call instead.
+//   var localFunctionImplicitCall = nullableFunction();
+//                                                   ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:87:52: Error: Method 'call' cannot be called on 'Function?' because it is potentially null.
+//  - 'Function' is from 'dart:core'.
+// Try calling using ?. instead.
+//   var localFunctionExplicitCall = nullableFunction.call();
+//                                                    ^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:88:47: Error: Property 'call' cannot be accessed on 'Function?' because it is potentially null.
+//  - 'Function' is from 'dart:core'.
+// Try accessing using ?. instead.
+//   var localFunctionTearOff = nullableFunction.call;
+//                                               ^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:89:59: Error: Can't use an expression of type 'void Function()?' as a function because it's potentially null.
+// Try calling using ?.call instead.
+//   var localFunctionTypeImplicitCall = nullableFunctionType();
+//                                                           ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:90:60: Error: Method 'call' cannot be called on 'void Function()?' because it is potentially null.
+// Try calling using ?. instead.
+//   var localFunctionTypeExplicitCall = nullableFunctionType.call();
+//                                                            ^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:91:55: Error: Property 'call' cannot be accessed on 'void Function()?' because it is potentially null.
+// Try accessing using ?. instead.
+//   var localFunctionTypeTearOff = nullableFunctionType.call;
+//                                                       ^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:92:42: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?.call instead.
+//   var localFunctionField = nullableClass.functionField();
+//                                          ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:93:46: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?.call instead.
+//   var localFunctionTypeField = nullableClass.functionTypeField();
+//                                              ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:94:43: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?.call instead.
+//   var localFunctionGetter = nullableClass.functionGetter();
+//                                           ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:95:47: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?.call instead.
+//   var localFunctionTypeGetter = nullableClass.functionTypeGetter();
+//                                               ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:97:44: Error: Operator '+' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+//   var localExtensionBinary = nullableClass + 0;
+//                                            ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:98:29: Error: Operator 'unary-' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+//   var localExtensionUnary = -nullableClass;
+//                             ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:99:45: Error: Operator '[]' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+//   var localExtensionIndexGet = nullableClass[0];
+//                                             ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:100:45: Error: Operator '[]=' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+//   var localExtensionIndexSet = nullableClass[0] = 1;
+//                                             ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:101:48: Error: Operator '[]' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+//   var localExtensionIndexGetSet = nullableClass[0] += 1;
+//                                                ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:101:48: Error: Operator '[]=' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+//   var localExtensionIndexGetSet = nullableClass[0] += 1;
+//                                                ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:102:49: Error: Property 'extensionProperty' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+//   var localExtensionPropertyGet = nullableClass.extensionProperty;
+//                                                 ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:103:49: Error: Property 'extensionProperty' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+//   var localExtensionPropertySet = nullableClass.extensionProperty = 1;
+//                                                 ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:104:52: Error: Property 'extensionProperty' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+//   var localExtensionPropertyGetSet = nullableClass.extensionProperty += 1;
+//                                                    ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:105:54: Error: Method 'extensionMethod' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?. instead.
+//   var localExtensionMethodInvocation = nullableClass.extensionMethod();
+//                                                      ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:106:51: Error: Property 'extensionMethod' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+//   var localExtensionMethodTearOff = nullableClass.extensionMethod;
+//                                                   ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:107:61: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?.call instead.
+//   var localExtensionFunctionTypeImplicitCall = nullableClass();
+//                                                             ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:108:62: Error: Method 'call' cannot be called on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?. instead.
+//   var localExtensionFunctionTypeExplicitCall = nullableClass.call();
+//                                                              ^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:109:57: Error: Property 'call' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try accessing using ?. instead.
+//   var localExtensionFunctionTypeTearOff = nullableClass.call;
+//                                                         ^^^^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:110:52: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?.call instead.
+//   var localExtensionFunctionGetter = nullableClass.extensionFunctionGetter();
+//                                                    ^
+//
+// pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:112:21: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+// Try calling using ?.call instead.
+//       nullableClass.extensionFunctionTypeGetter();
+//                     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int property = 0;
+  field core::Function functionField = () → Null {};
+  field () → void functionTypeField = () → void {};
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  method method() → core::int
+    return 0;
+  get functionGetter() → core::Function
+    return () → Null {};
+  get functionTypeGetter() → () → void
+    return () → void {};
+}
+extension Extension on self::Class {
+  operator + = self::Extension|+;
+  operator unary- = self::Extension|unary-;
+  operator [] = self::Extension|[];
+  operator []= = self::Extension|[]=;
+  method call = self::Extension|call;
+  tearoff call = self::Extension|get#call;
+  get extensionProperty = self::Extension|get#extensionProperty;
+  method extensionMethod = self::Extension|extensionMethod;
+  tearoff extensionMethod = self::Extension|get#extensionMethod;
+  get extensionFunctionGetter = self::Extension|get#extensionFunctionGetter;
+  get extensionFunctionTypeGetter = self::Extension|get#extensionFunctionTypeGetter;
+  set extensionProperty = self::Extension|set#extensionProperty;
+}
+static field core::num topLevelBinary = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:37:34: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+var topLevelBinary = nullableInt + 0;
+                                 ^" in self::nullableInt.{core::num::+}(0){(core::num) → core::num};
+static field core::int topLevelUnary = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:38:21: Error: Operator 'unary-' cannot be called on 'int?' because it is potentially null.
+var topLevelUnary = -nullableInt;
+                    ^" in self::nullableInt.{core::int::unary-}(){() → core::int};
+static field dynamic topLevelIndexGet = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:39:35: Error: Operator '[]' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+ - 'Map' is from 'dart:core'.
+var topLevelIndexGet = nullableMap[0];
+                                  ^" in self::nullableMap.{core::Map::[]}{<nullable>}.(0){(core::Object?) → dynamic};
+static field core::int topLevelIndexSet = let final core::Map<dynamic, dynamic>? #t1 = self::nullableMap in let final core::int #t2 = 0 in let final core::int #t3 = 1 in let final void #t4 = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:40:35: Error: Operator '[]=' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+ - 'Map' is from 'dart:core'.
+var topLevelIndexSet = nullableMap[0] = 1;
+                                  ^" in #t1.{core::Map::[]=}{<nullable>}.(#t2, #t3){(dynamic, dynamic) → void} in #t3;
+static field dynamic topLevelIndexGetSet = let final core::Map<dynamic, dynamic>? #t5 = self::nullableMap in let final core::int #t6 = 0 in let final dynamic #t7 = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:41:38: Error: Operator '[]' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+ - 'Map' is from 'dart:core'.
+var topLevelIndexGetSet = nullableMap[0] += 1;
+                                     ^" in #t5.{core::Map::[]}{<nullable>}.(#t6){(core::Object?) → dynamic}{dynamic}.+(1) in let final void #t8 = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:41:38: Error: Operator '[]=' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+ - 'Map' is from 'dart:core'.
+var topLevelIndexGetSet = nullableMap[0] += 1;
+                                     ^" in #t5.{core::Map::[]=}{<nullable>}.(#t6, #t7){(dynamic, dynamic) → void} in #t7;
+static field core::int topLevelPropertyGet = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:42:41: Error: Property 'property' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+var topLevelPropertyGet = nullableClass.property;
+                                        ^^^^^^^^" in self::nullableClass.{self::Class::property}{<nullable>}.{core::int};
+static field core::int topLevelPropertySet = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:43:41: Error: Property 'property' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+var topLevelPropertySet = nullableClass.property = 1;
+                                        ^^^^^^^^" in self::nullableClass.{self::Class::property}{<nullable>}. = 1;
+static field core::int topLevelPropertyGetSet = let final self::Class? #t9 = self::nullableClass in invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:44:44: Error: Property 'property' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+var topLevelPropertyGetSet = nullableClass.property += 1;
+                                           ^^^^^^^^" in #t9.{self::Class::property}{<nullable>}. = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:44:44: Error: Property 'property' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+var topLevelPropertyGetSet = nullableClass.property += 1;
+                                           ^^^^^^^^" in #t9.{self::Class::property}{<nullable>}.{core::int}.{core::num::+}(1){(core::num) → core::int};
+static field core::int topLevelMethodInvocation = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:45:46: Error: Method 'method' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?. instead.
+var topLevelMethodInvocation = nullableClass.method();
+                                             ^^^^^^" in self::nullableClass.{self::Class::method}{<nullable>}.(){() → core::int};
+static field () → core::int topLevelMethodTearOff = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:46:43: Error: Property 'method' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+var topLevelMethodTearOff = nullableClass.method;
+                                          ^^^^^^" in self::nullableClass.{self::Class::method}{<nullable>}.{() → core::int};
+static field dynamic topLevelFunctionImplicitCall = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:47:52: Error: Can't use an expression of type 'Function?' as a function because it's potentially null.
+ - 'Function' is from 'dart:core'.
+Try calling using ?.call instead.
+var topLevelFunctionImplicitCall = nullableFunction();
+                                                   ^" in self::nullableFunction{<nullable>}.();
+static field dynamic topLevelFunctionExplicitCall = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:48:53: Error: Method 'call' cannot be called on 'Function?' because it is potentially null.
+ - 'Function' is from 'dart:core'.
+Try calling using ?. instead.
+var topLevelFunctionExplicitCall = nullableFunction.call();
+                                                    ^^^^" in self::nullableFunction{<nullable>}.();
+static field core::Function? topLevelFunctionTearOff = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:49:48: Error: Property 'call' cannot be accessed on 'Function?' because it is potentially null.
+ - 'Function' is from 'dart:core'.
+Try accessing using ?. instead.
+var topLevelFunctionTearOff = nullableFunction.call;
+                                               ^^^^" in self::nullableFunction.call;
+static field void topLevelFunctionTypeImplicitCall = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:50:60: Error: Can't use an expression of type 'void Function()?' as a function because it's potentially null.
+Try calling using ?.call instead.
+var topLevelFunctionTypeImplicitCall = nullableFunctionType();
+                                                           ^" in self::nullableFunctionType{<nullable>}.(){() →? void};
+static field void topLevelFunctionTypeExplicitCall = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:51:61: Error: Method 'call' cannot be called on 'void Function()?' because it is potentially null.
+Try calling using ?. instead.
+var topLevelFunctionTypeExplicitCall = nullableFunctionType.call();
+                                                            ^^^^" in self::nullableFunctionType{<nullable>}.(){() →? void};
+static field () →? void topLevelFunctionTypeTearOff = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:52:56: Error: Property 'call' cannot be accessed on 'void Function()?' because it is potentially null.
+Try accessing using ?. instead.
+var topLevelFunctionTypeTearOff = nullableFunctionType.call;
+                                                       ^^^^" in self::nullableFunctionType.call;
+static field dynamic topLevelFunctionField = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:53:43: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?.call instead.
+var topLevelFunctionField = nullableClass.functionField();
+                                          ^" in self::nullableClass.{self::Class::functionField}{<nullable>}.{core::Function}();
+static field void topLevelFunctionTypeField = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:54:47: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?.call instead.
+var topLevelFunctionTypeField = nullableClass.functionTypeField();
+                                              ^" in self::nullableClass.{self::Class::functionTypeField}{<nullable>}.{() → void}(){() → void};
+static field dynamic topLevelFunctionGetter = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:55:44: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?.call instead.
+var topLevelFunctionGetter = nullableClass.functionGetter();
+                                           ^" in self::nullableClass.{self::Class::functionGetter}{<nullable>}.{core::Function}();
+static field void topLevelFunctionTypeGetter = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:56:48: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?.call instead.
+var topLevelFunctionTypeGetter = nullableClass.functionTypeGetter();
+                                               ^" in self::nullableClass.{self::Class::functionTypeGetter}{<nullable>}.{() → void}(){() → void};
+static field core::int topLevelExtensionBinary = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:58:45: Error: Operator '+' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+var topLevelExtensionBinary = nullableClass + 0;
+                                            ^" in self::Extension|+(self::nullableClass, 0);
+static field core::int topLevelExtensionUnary = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:59:30: Error: Operator 'unary-' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+var topLevelExtensionUnary = -nullableClass;
+                             ^" in self::Extension|unary-(self::nullableClass);
+static field core::int topLevelExtensionIndexGet = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:60:46: Error: Operator '[]' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+var topLevelExtensionIndexGet = nullableClass[0];
+                                             ^" in self::Extension|[](self::nullableClass, 0);
+static field core::int topLevelExtensionIndexSet = let final self::Class? #t10 = self::nullableClass in let final core::int #t11 = 0 in let final core::int #t12 = 1 in let final void #t13 = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:61:46: Error: Operator '[]=' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+var topLevelExtensionIndexSet = nullableClass[0] = 1;
+                                             ^" in self::Extension|[]=(#t10, #t11, #t12) in #t12;
+static field core::int topLevelExtensionIndexGetSet = let final self::Class? #t14 = self::nullableClass in let final core::int #t15 = 0 in let final core::int #t16 = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:62:49: Error: Operator '[]' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+var topLevelExtensionIndexGetSet = nullableClass[0] += 1;
+                                                ^" in self::Extension|[](#t14, #t15).{core::num::+}(1){(core::num) → core::int} in let final void #t17 = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:62:49: Error: Operator '[]=' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+var topLevelExtensionIndexGetSet = nullableClass[0] += 1;
+                                                ^" in self::Extension|[]=(#t14, #t15, #t16) in #t16;
+static field core::int topLevelExtensionPropertyGet = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:63:50: Error: Property 'extensionProperty' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+var topLevelExtensionPropertyGet = nullableClass.extensionProperty;
+                                                 ^^^^^^^^^^^^^^^^^" in self::Extension|get#extensionProperty(self::nullableClass);
+static field core::int topLevelExtensionPropertySet = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:64:50: Error: Property 'extensionProperty' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+var topLevelExtensionPropertySet = nullableClass.extensionProperty = 1;
+                                                 ^^^^^^^^^^^^^^^^^" in let final core::int #t18 = 1 in let final void #t19 = self::Extension|set#extensionProperty(self::nullableClass, #t18) in #t18;
+static field core::int topLevelExtensionPropertyGetSet = let final self::Class? #t20 = self::nullableClass in invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:65:53: Error: Property 'extensionProperty' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+var topLevelExtensionPropertyGetSet = nullableClass.extensionProperty += 1;
+                                                    ^^^^^^^^^^^^^^^^^" in let final core::int #t21 = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:65:53: Error: Property 'extensionProperty' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+var topLevelExtensionPropertyGetSet = nullableClass.extensionProperty += 1;
+                                                    ^^^^^^^^^^^^^^^^^" in self::Extension|get#extensionProperty(#t20).{core::num::+}(1){(core::num) → core::int} in let final void #t22 = self::Extension|set#extensionProperty(#t20, #t21) in #t21;
+static field core::int topLevelExtensionMethodInvocation = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:66:55: Error: Method 'extensionMethod' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?. instead.
+var topLevelExtensionMethodInvocation = nullableClass.extensionMethod();
+                                                      ^^^^^^^^^^^^^^^" in self::Extension|extensionMethod(self::nullableClass);
+static field () → core::int topLevelExtensionMethodTearOff = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:67:52: Error: Property 'extensionMethod' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+var topLevelExtensionMethodTearOff = nullableClass.extensionMethod;
+                                                   ^^^^^^^^^^^^^^^" in self::Extension|get#extensionMethod(self::nullableClass);
+static field core::int topLevelExtensionFunctionTypeImplicitCall = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:68:62: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?.call instead.
+var topLevelExtensionFunctionTypeImplicitCall = nullableClass();
+                                                             ^" in self::Extension|call(self::nullableClass);
+static field core::int topLevelExtensionFunctionTypeExplicitCall = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:69:63: Error: Method 'call' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?. instead.
+var topLevelExtensionFunctionTypeExplicitCall = nullableClass.call();
+                                                              ^^^^" in self::Extension|call(self::nullableClass);
+static field () → core::int topLevelExtensionFunctionTypeTearOff = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:70:58: Error: Property 'call' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+var topLevelExtensionFunctionTypeTearOff = nullableClass.call;
+                                                         ^^^^" in self::Extension|get#call(self::nullableClass);
+static field dynamic topLevelExtensionFunctionGetter = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:71:53: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?.call instead.
+var topLevelExtensionFunctionGetter = nullableClass.extensionFunctionGetter();
+                                                    ^" in self::Extension|get#extensionFunctionGetter(self::nullableClass)();
+static field void topLevelExtensionFunctionTypeGetter = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:73:19: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?.call instead.
+    nullableClass.extensionFunctionTypeGetter();
+                  ^" in self::Extension|get#extensionFunctionTypeGetter(self::nullableClass)(){() → void};
+static method Extension|+(lowered final self::Class #this, core::int value) → core::int
+  return 0;
+static method Extension|unary-(lowered final self::Class #this) → core::int
+  return 0;
+static method Extension|[](lowered final self::Class #this, core::int index) → core::int
+  return 0;
+static method Extension|[]=(lowered final self::Class #this, core::int index, core::int value) → void {}
+static method Extension|call(lowered final self::Class #this) → core::int
+  return 0;
+static method Extension|get#call(lowered final self::Class #this) → () → core::int
+  return () → core::int => self::Extension|call(#this);
+static method Extension|get#extensionProperty(lowered final self::Class #this) → core::int
+  return 0;
+static method Extension|set#extensionProperty(lowered final self::Class #this, core::int value) → void {}
+static method Extension|extensionMethod(lowered final self::Class #this) → core::int
+  return 0;
+static method Extension|get#extensionMethod(lowered final self::Class #this) → () → core::int
+  return () → core::int => self::Extension|extensionMethod(#this);
+static method Extension|get#extensionFunctionGetter(lowered final self::Class #this) → core::Function
+  return () → Null {};
+static method Extension|get#extensionFunctionTypeGetter(lowered final self::Class #this) → () → void
+  return () → void {};
+static get nullableFunction() → core::Function?
+  return () → Null {};
+static get nullableFunctionType() → () →? void
+  return () → void {};
+static get nullableInt() → core::int?
+  return 0;
+static get nullableMap() → core::Map<dynamic, dynamic>?
+  return <dynamic, dynamic>{};
+static get nullableClass() → self::Class?
+  return new self::Class::•();
+static method test() → dynamic {
+  core::num localBinary = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:76:33: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+  var localBinary = nullableInt + 0;
+                                ^" in self::nullableInt.{core::num::+}(0){(core::num) → core::num};
+  core::int localUnary = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:77:20: Error: Operator 'unary-' cannot be called on 'int?' because it is potentially null.
+  var localUnary = -nullableInt;
+                   ^" in self::nullableInt.{core::int::unary-}(){() → core::int};
+  dynamic localIndexGet = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:78:34: Error: Operator '[]' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+ - 'Map' is from 'dart:core'.
+  var localIndexGet = nullableMap[0];
+                                 ^" in self::nullableMap.{core::Map::[]}{<nullable>}.(0){(core::Object?) → dynamic};
+  core::int localIndexSet = let final core::Map<dynamic, dynamic>? #t23 = self::nullableMap in let final core::int #t24 = 0 in let final core::int #t25 = 1 in let final void #t26 = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:79:34: Error: Operator '[]=' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+ - 'Map' is from 'dart:core'.
+  var localIndexSet = nullableMap[0] = 1;
+                                 ^" in #t23.{core::Map::[]=}{<nullable>}.(#t24, #t25){(dynamic, dynamic) → void} in #t25;
+  dynamic localIndexGetSet = let final core::Map<dynamic, dynamic>? #t27 = self::nullableMap in let final core::int #t28 = 0 in let final dynamic #t29 = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:80:37: Error: Operator '[]' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+ - 'Map' is from 'dart:core'.
+  var localIndexGetSet = nullableMap[0] += 1;
+                                    ^" in #t27.{core::Map::[]}{<nullable>}.(#t28){(core::Object?) → dynamic}{dynamic}.+(1) in let final void #t30 = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:80:37: Error: Operator '[]=' cannot be called on 'Map<dynamic, dynamic>?' because it is potentially null.
+ - 'Map' is from 'dart:core'.
+  var localIndexGetSet = nullableMap[0] += 1;
+                                    ^" in #t27.{core::Map::[]=}{<nullable>}.(#t28, #t29){(dynamic, dynamic) → void} in #t29;
+  core::int localPropertyGet = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:81:40: Error: Property 'property' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+  var localPropertyGet = nullableClass.property;
+                                       ^^^^^^^^" in self::nullableClass.{self::Class::property}{<nullable>}.{core::int};
+  core::int localPropertySet = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:82:40: Error: Property 'property' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+  var localPropertySet = nullableClass.property = 1;
+                                       ^^^^^^^^" in self::nullableClass.{self::Class::property}{<nullable>}. = 1;
+  core::int localPropertyGetSet = let final self::Class? #t31 = self::nullableClass in invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:83:43: Error: Property 'property' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+  var localPropertyGetSet = nullableClass.property += 1;
+                                          ^^^^^^^^" in #t31.{self::Class::property}{<nullable>}. = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:83:43: Error: Property 'property' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+  var localPropertyGetSet = nullableClass.property += 1;
+                                          ^^^^^^^^" in #t31.{self::Class::property}{<nullable>}.{core::int}.{core::num::+}(1){(core::num) → core::int};
+  core::int localMethodInvocation = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:84:45: Error: Method 'method' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?. instead.
+  var localMethodInvocation = nullableClass.method();
+                                            ^^^^^^" in self::nullableClass.{self::Class::method}{<nullable>}.(){() → core::int};
+  () → core::int localMethodTearOff = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:85:42: Error: Property 'method' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+  var localMethodTearOff = nullableClass.method;
+                                         ^^^^^^" in self::nullableClass.{self::Class::method}{<nullable>}.{() → core::int};
+  dynamic localFunctionImplicitCall = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:86:51: Error: Can't use an expression of type 'Function?' as a function because it's potentially null.
+ - 'Function' is from 'dart:core'.
+Try calling using ?.call instead.
+  var localFunctionImplicitCall = nullableFunction();
+                                                  ^" in self::nullableFunction{<nullable>}.();
+  dynamic localFunctionExplicitCall = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:87:52: Error: Method 'call' cannot be called on 'Function?' because it is potentially null.
+ - 'Function' is from 'dart:core'.
+Try calling using ?. instead.
+  var localFunctionExplicitCall = nullableFunction.call();
+                                                   ^^^^" in self::nullableFunction{<nullable>}.();
+  core::Function? localFunctionTearOff = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:88:47: Error: Property 'call' cannot be accessed on 'Function?' because it is potentially null.
+ - 'Function' is from 'dart:core'.
+Try accessing using ?. instead.
+  var localFunctionTearOff = nullableFunction.call;
+                                              ^^^^" in self::nullableFunction.call;
+  void localFunctionTypeImplicitCall = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:89:59: Error: Can't use an expression of type 'void Function()?' as a function because it's potentially null.
+Try calling using ?.call instead.
+  var localFunctionTypeImplicitCall = nullableFunctionType();
+                                                          ^" in self::nullableFunctionType{<nullable>}.(){() →? void};
+  void localFunctionTypeExplicitCall = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:90:60: Error: Method 'call' cannot be called on 'void Function()?' because it is potentially null.
+Try calling using ?. instead.
+  var localFunctionTypeExplicitCall = nullableFunctionType.call();
+                                                           ^^^^" in self::nullableFunctionType{<nullable>}.(){() →? void};
+  () →? void localFunctionTypeTearOff = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:91:55: Error: Property 'call' cannot be accessed on 'void Function()?' because it is potentially null.
+Try accessing using ?. instead.
+  var localFunctionTypeTearOff = nullableFunctionType.call;
+                                                      ^^^^" in self::nullableFunctionType.call;
+  dynamic localFunctionField = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:92:42: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?.call instead.
+  var localFunctionField = nullableClass.functionField();
+                                         ^" in self::nullableClass.{self::Class::functionField}{<nullable>}.{core::Function}();
+  void localFunctionTypeField = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:93:46: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?.call instead.
+  var localFunctionTypeField = nullableClass.functionTypeField();
+                                             ^" in self::nullableClass.{self::Class::functionTypeField}{<nullable>}.{() → void}(){() → void};
+  dynamic localFunctionGetter = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:94:43: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?.call instead.
+  var localFunctionGetter = nullableClass.functionGetter();
+                                          ^" in self::nullableClass.{self::Class::functionGetter}{<nullable>}.{core::Function}();
+  void localFunctionTypeGetter = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:95:47: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?.call instead.
+  var localFunctionTypeGetter = nullableClass.functionTypeGetter();
+                                              ^" in self::nullableClass.{self::Class::functionTypeGetter}{<nullable>}.{() → void}(){() → void};
+  core::int localExtensionBinary = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:97:44: Error: Operator '+' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+  var localExtensionBinary = nullableClass + 0;
+                                           ^" in self::Extension|+(self::nullableClass, 0);
+  core::int localExtensionUnary = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:98:29: Error: Operator 'unary-' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+  var localExtensionUnary = -nullableClass;
+                            ^" in self::Extension|unary-(self::nullableClass);
+  core::int localExtensionIndexGet = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:99:45: Error: Operator '[]' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+  var localExtensionIndexGet = nullableClass[0];
+                                            ^" in self::Extension|[](self::nullableClass, 0);
+  core::int localExtensionIndexSet = let final self::Class? #t32 = self::nullableClass in let final core::int #t33 = 0 in let final core::int #t34 = 1 in let final void #t35 = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:100:45: Error: Operator '[]=' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+  var localExtensionIndexSet = nullableClass[0] = 1;
+                                            ^" in self::Extension|[]=(#t32, #t33, #t34) in #t34;
+  core::int localExtensionIndexGetSet = let final self::Class? #t36 = self::nullableClass in let final core::int #t37 = 0 in let final core::int #t38 = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:101:48: Error: Operator '[]' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+  var localExtensionIndexGetSet = nullableClass[0] += 1;
+                                               ^" in self::Extension|[](#t36, #t37).{core::num::+}(1){(core::num) → core::int} in let final void #t39 = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:101:48: Error: Operator '[]=' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+  var localExtensionIndexGetSet = nullableClass[0] += 1;
+                                               ^" in self::Extension|[]=(#t36, #t37, #t38) in #t38;
+  core::int localExtensionPropertyGet = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:102:49: Error: Property 'extensionProperty' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+  var localExtensionPropertyGet = nullableClass.extensionProperty;
+                                                ^^^^^^^^^^^^^^^^^" in self::Extension|get#extensionProperty(self::nullableClass);
+  core::int localExtensionPropertySet = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:103:49: Error: Property 'extensionProperty' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+  var localExtensionPropertySet = nullableClass.extensionProperty = 1;
+                                                ^^^^^^^^^^^^^^^^^" in let final core::int #t40 = 1 in let final void #t41 = self::Extension|set#extensionProperty(self::nullableClass, #t40) in #t40;
+  core::int localExtensionPropertyGetSet = let final self::Class? #t42 = self::nullableClass in invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:104:52: Error: Property 'extensionProperty' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+  var localExtensionPropertyGetSet = nullableClass.extensionProperty += 1;
+                                                   ^^^^^^^^^^^^^^^^^" in let final core::int #t43 = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:104:52: Error: Property 'extensionProperty' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+  var localExtensionPropertyGetSet = nullableClass.extensionProperty += 1;
+                                                   ^^^^^^^^^^^^^^^^^" in self::Extension|get#extensionProperty(#t42).{core::num::+}(1){(core::num) → core::int} in let final void #t44 = self::Extension|set#extensionProperty(#t42, #t43) in #t43;
+  core::int localExtensionMethodInvocation = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:105:54: Error: Method 'extensionMethod' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?. instead.
+  var localExtensionMethodInvocation = nullableClass.extensionMethod();
+                                                     ^^^^^^^^^^^^^^^" in self::Extension|extensionMethod(self::nullableClass);
+  () → core::int localExtensionMethodTearOff = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:106:51: Error: Property 'extensionMethod' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+  var localExtensionMethodTearOff = nullableClass.extensionMethod;
+                                                  ^^^^^^^^^^^^^^^" in self::Extension|get#extensionMethod(self::nullableClass);
+  core::int localExtensionFunctionTypeImplicitCall = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:107:61: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?.call instead.
+  var localExtensionFunctionTypeImplicitCall = nullableClass();
+                                                            ^" in self::Extension|call(self::nullableClass);
+  core::int localExtensionFunctionTypeExplicitCall = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:108:62: Error: Method 'call' cannot be called on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?. instead.
+  var localExtensionFunctionTypeExplicitCall = nullableClass.call();
+                                                             ^^^^" in self::Extension|call(self::nullableClass);
+  () → core::int localExtensionFunctionTypeTearOff = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:109:57: Error: Property 'call' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try accessing using ?. instead.
+  var localExtensionFunctionTypeTearOff = nullableClass.call;
+                                                        ^^^^" in self::Extension|get#call(self::nullableClass);
+  dynamic localExtensionFunctionGetter = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:110:52: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?.call instead.
+  var localExtensionFunctionGetter = nullableClass.extensionFunctionGetter();
+                                                   ^" in self::Extension|get#extensionFunctionGetter(self::nullableClass)();
+  void localExtensionFunctionTypeGetter = invalid-expression "pkg/front_end/testcases/nnbd/potentially_nullable_access.dart:112:21: Error: Can't use an expression of type 'Class?' as a function because it's potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/potentially_nullable_access.dart'.
+Try calling using ?.call instead.
+      nullableClass.extensionFunctionTypeGetter();
+                    ^" in self::Extension|get#extensionFunctionTypeGetter(self::nullableClass)(){() → void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/pure_index_expressions.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/pure_index_expressions.dart.weak.modular.expect
new file mode 100644
index 0000000..42b09ab8
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/pure_index_expressions.dart.weak.modular.expect
@@ -0,0 +1,334 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:25:8: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     map[this] ??= this;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:26:8: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     map[self] ??= self;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:42:12: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     v = map[this] ??= this;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:43:12: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     v = map[self] ??= self;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:58:6: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     i[this] ??= this;
+//      ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:59:6: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     i[self] ??= self;
+//      ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:75:10: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     v = i[this] ??= this;
+//          ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:76:10: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     v = i[self] ??= self;
+//          ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:91:17: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     Extension(i)[this] ??= this;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:92:17: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     Extension(i)[self] ??= self;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:108:21: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     v = Extension(i)[this] ??= this;
+//                     ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:109:21: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     v = Extension(i)[self] ??= self;
+//                     ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:126:10: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     super[this] ??= this;
+//          ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:127:10: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     super[self] ??= self;
+//          ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:143:14: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     v = super[this] ??= this;
+//              ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:144:14: Warning: Operand of null-aware operation '??=' has type 'Class' which excludes null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     v = super[self] ??= self;
+//              ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:168:9: Warning: Operand of null-aware operation '??=' has type 'Class2' which excludes null.
+//  - 'Class2' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     this[this] ??= this;
+//         ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:169:9: Warning: Operand of null-aware operation '??=' has type 'Class2' which excludes null.
+//  - 'Class2' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     self[self] ??= self;
+//         ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:185:13: Warning: Operand of null-aware operation '??=' has type 'Class2' which excludes null.
+//  - 'Class2' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     v = this[this] ??= this;
+//             ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:186:13: Warning: Operand of null-aware operation '??=' has type 'Class2' which excludes null.
+//  - 'Class2' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     v = self[self] ??= self;
+//             ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:201:21: Warning: Operand of null-aware operation '??=' has type 'Class2' which excludes null.
+//  - 'Class2' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     Extension2(this)[this] ??= this;
+//                     ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:202:21: Warning: Operand of null-aware operation '??=' has type 'Class2' which excludes null.
+//  - 'Class2' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     Extension2(self)[self] ??= self;
+//                     ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:218:25: Warning: Operand of null-aware operation '??=' has type 'Class2' which excludes null.
+//  - 'Class2' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     v = Extension2(this)[this] ??= this;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd/pure_index_expressions.dart:219:25: Warning: Operand of null-aware operation '??=' has type 'Class2' which excludes null.
+//  - 'Class2' is from 'pkg/front_end/testcases/nnbd/pure_index_expressions.dart'.
+//     v = Extension2(self)[self] ??= self;
+//                         ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Map<K extends core::Object? = dynamic, V extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Map<self::Map::K%, self::Map::V%>
+    : super core::Object::•()
+    ;
+  abstract operator [](covariant-by-class self::Map::K% index) → self::Map::V%;
+  abstract operator []=(covariant-by-class self::Map::K% index, covariant-by-class self::Map::V% value) → void;
+}
+class Class extends core::Object {
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  operator [](self::Class cls) → self::Class
+    return new self::Class::•();
+  operator []=(self::Class cls, self::Class value) → void {}
+  operator +(self::Class cls) → self::Class
+    return cls;
+  method indexGetSetForEffect(self::Map<self::Class, self::Class> map) → void {
+    late final self::Class self;
+    if(self::b)
+      self = this;
+    let final self::Map<self::Class, self::Class> #t1 = map in #t1.{self::Map::[]}(this){(self::Class) → self::Class} == null ?{self::Class} #t1.{self::Map::[]=}(this, this){(self::Class, self::Class) → void} : null;
+    let final self::Map<self::Class, self::Class> #t2 = map in let final self::Class #t3 = self in #t2.{self::Map::[]}(#t3){(self::Class) → self::Class} == null ?{self::Class} #t2.{self::Map::[]=}(#t3, self){(self::Class, self::Class) → void} : null;
+    map.{self::Map::[]=}(this, this){(self::Class, self::Class) → void};
+    map.{self::Map::[]=}(self, self){(self::Class, self::Class) → void};
+    map.{self::Map::[]}(this){(self::Class) → self::Class};
+    map.{self::Map::[]}(self){(self::Class) → self::Class};
+    let final self::Map<self::Class, self::Class> #t4 = map in #t4.{self::Map::[]=}(this, #t4.{self::Map::[]}(this){(self::Class) → self::Class}.{self::Class::+}(this){(self::Class) → self::Class}){(self::Class, self::Class) → void};
+    let final self::Map<self::Class, self::Class> #t5 = map in let final self::Class #t6 = self in #t5.{self::Map::[]=}(#t6, #t5.{self::Map::[]}(#t6){(self::Class) → self::Class}.{self::Class::+}(self){(self::Class) → self::Class}){(self::Class, self::Class) → void};
+  }
+  method indexGetSetForValue(self::Map<self::Class, self::Class> map) → void {
+    late final self::Class self;
+    if(self::b)
+      self = this;
+    dynamic v;
+    v = let final self::Map<self::Class, self::Class> #t7 = map in let final self::Class #t8 = #t7.{self::Map::[]}(this){(self::Class) → self::Class} in #t8 == null ?{self::Class} let final void #t9 = #t7.{self::Map::[]=}(this, this){(self::Class, self::Class) → void} in this : #t8;
+    v = let final self::Map<self::Class, self::Class> #t10 = map in let final self::Class #t11 = self in let final self::Class #t12 = #t10.{self::Map::[]}(#t11){(self::Class) → self::Class} in #t12 == null ?{self::Class} let final self::Class #t13 = self in let final void #t14 = #t10.{self::Map::[]=}(#t11, #t13){(self::Class, self::Class) → void} in #t13 : #t12;
+    v = let final self::Map<self::Class, self::Class> #t15 = map in let final void #t16 = #t15.{self::Map::[]=}(this, this){(self::Class, self::Class) → void} in this;
+    v = let final self::Map<self::Class, self::Class> #t17 = map in let final self::Class #t18 = self in let final self::Class #t19 = self in let final void #t20 = #t17.{self::Map::[]=}(#t18, #t19){(self::Class, self::Class) → void} in #t19;
+    v = map.{self::Map::[]}(this){(self::Class) → self::Class};
+    v = map.{self::Map::[]}(self){(self::Class) → self::Class};
+    v = let final self::Map<self::Class, self::Class> #t21 = map in let final self::Class #t22 = #t21.{self::Map::[]}(this){(self::Class) → self::Class}.{self::Class::+}(this){(self::Class) → self::Class} in let final void #t23 = #t21.{self::Map::[]=}(this, #t22){(self::Class, self::Class) → void} in #t22;
+    v = let final self::Map<self::Class, self::Class> #t24 = map in let final self::Class #t25 = self in let final self::Class #t26 = #t24.{self::Map::[]}(#t25){(self::Class) → self::Class}.{self::Class::+}(self){(self::Class) → self::Class} in let final void #t27 = #t24.{self::Map::[]=}(#t25, #t26){(self::Class, self::Class) → void} in #t26;
+  }
+  method implicitExtensionGetSetForEffect(core::int i) → void {
+    late final self::Class self;
+    if(self::b)
+      self = this;
+    let final core::int #t28 = i in self::Extension|[](#t28, this) == null ?{self::Class} self::Extension|[]=(#t28, this, this) : null;
+    let final core::int #t29 = i in let final self::Class #t30 = self in self::Extension|[](#t29, #t30) == null ?{self::Class} self::Extension|[]=(#t29, #t30, self) : null;
+    self::Extension|[]=(i, this, this);
+    self::Extension|[]=(i, self, self);
+    self::Extension|[](i, this);
+    self::Extension|[](i, self);
+    let final core::int #t31 = i in self::Extension|[]=(#t31, this, self::Extension|[](#t31, this).{self::Class::+}(this){(self::Class) → self::Class});
+    let final core::int #t32 = i in let final self::Class #t33 = self in self::Extension|[]=(#t32, #t33, self::Extension|[](#t32, #t33).{self::Class::+}(self){(self::Class) → self::Class});
+  }
+  method implicitExtensionGetSetForValue(core::int i) → void {
+    late final self::Class self;
+    if(self::b)
+      self = this;
+    dynamic v;
+    v = let final core::int #t34 = i in let final self::Class #t35 = self::Extension|[](#t34, this) in #t35 == null ?{self::Class} let final void #t36 = self::Extension|[]=(#t34, this, this) in this : #t35;
+    v = let final core::int #t37 = i in let final self::Class #t38 = self in let final self::Class #t39 = self::Extension|[](#t37, #t38) in #t39 == null ?{self::Class} let final self::Class #t40 = self in let final void #t41 = self::Extension|[]=(#t37, #t38, #t40) in #t40 : #t39;
+    v = let final core::int #t42 = i in let final void #t43 = self::Extension|[]=(#t42, this, this) in this;
+    v = let final core::int #t44 = i in let final self::Class #t45 = self in let final self::Class #t46 = self in let final void #t47 = self::Extension|[]=(#t44, #t45, #t46) in #t46;
+    v = self::Extension|[](i, this);
+    v = self::Extension|[](i, self);
+    v = let final core::int #t48 = i in let final self::Class #t49 = self::Extension|[](#t48, this).{self::Class::+}(this){(self::Class) → self::Class} in let final void #t50 = self::Extension|[]=(#t48, this, #t49) in #t49;
+    v = let final core::int #t51 = i in let final self::Class #t52 = self in let final self::Class #t53 = self::Extension|[](#t51, #t52).{self::Class::+}(self){(self::Class) → self::Class} in let final void #t54 = self::Extension|[]=(#t51, #t52, #t53) in #t53;
+  }
+  method explicitExtensionGetSetForEffect(core::int i) → void {
+    late final self::Class self;
+    if(self::b)
+      self = this;
+    let final core::int #t55 = i in self::Extension|[](#t55, this) == null ?{self::Class} self::Extension|[]=(#t55, this, this) : null;
+    let final core::int #t56 = i in let final self::Class #t57 = self in self::Extension|[](#t56, #t57) == null ?{self::Class} self::Extension|[]=(#t56, #t57, self) : null;
+    self::Extension|[]=(i, this, this);
+    self::Extension|[]=(i, self, self);
+    self::Extension|[](i, this);
+    self::Extension|[](i, self);
+    let final core::int #t58 = i in self::Extension|[]=(#t58, this, self::Extension|[](#t58, this).{self::Class::+}(this){(self::Class) → self::Class});
+    let final core::int #t59 = i in let final self::Class #t60 = self in self::Extension|[]=(#t59, #t60, self::Extension|[](#t59, #t60).{self::Class::+}(self){(self::Class) → self::Class});
+  }
+  method explicitExtensionGetSetForValue(core::int i) → void {
+    late final self::Class self;
+    if(self::b)
+      self = this;
+    dynamic v;
+    v = let final core::int #t61 = i in let final self::Class #t62 = self::Extension|[](#t61, this) in #t62 == null ?{self::Class} let final void #t63 = self::Extension|[]=(#t61, this, this) in this : #t62;
+    v = let final core::int #t64 = i in let final self::Class #t65 = self in let final self::Class #t66 = self::Extension|[](#t64, #t65) in #t66 == null ?{self::Class} let final self::Class #t67 = self in let final void #t68 = self::Extension|[]=(#t64, #t65, #t67) in #t67 : #t66;
+    v = let final core::int #t69 = i in let final void #t70 = self::Extension|[]=(#t69, this, this) in this;
+    v = let final core::int #t71 = i in let final self::Class #t72 = self in let final void #t73 = self::Extension|[]=(#t71, self, #t72) in #t72;
+    v = self::Extension|[](i, this);
+    v = self::Extension|[](i, self);
+    v = let final core::int #t74 = i in let final self::Class #t75 = self::Extension|[](#t74, this).{self::Class::+}(this){(self::Class) → self::Class} in let final void #t76 = self::Extension|[]=(#t74, this, #t75) in #t75;
+    v = let final core::int #t77 = i in let final self::Class #t78 = self in let final self::Class #t79 = self::Extension|[](#t77, #t78).{self::Class::+}(self){(self::Class) → self::Class} in let final void #t80 = self::Extension|[]=(#t77, #t78, #t79) in #t79;
+  }
+}
+class Subclass extends self::Class {
+  synthetic constructor •() → self::Subclass
+    : super self::Class::•()
+    ;
+  method superIndexGetSetForEffect() → void {
+    late final self::Class self;
+    if(self::b)
+      self = this;
+    super.{self::Class::[]}(this) == null ?{self::Class} super.{self::Class::[]=}(this, this) : null;
+    let final self::Class #t81 = self in super.{self::Class::[]}(#t81) == null ?{self::Class} super.{self::Class::[]=}(#t81, self) : null;
+    super.{self::Class::[]=}(this, this);
+    super.{self::Class::[]=}(self, self);
+    super.{self::Class::[]}(this);
+    super.{self::Class::[]}(self);
+    super.{self::Class::[]=}(this, super.{self::Class::[]}(this).{self::Class::+}(this){(self::Class) → self::Class});
+    let final self::Class #t82 = self in super.{self::Class::[]=}(#t82, super.{self::Class::[]}(#t82).{self::Class::+}(self){(self::Class) → self::Class});
+  }
+  method superIndexGetSetForValue() → void {
+    late final self::Class self;
+    if(self::b)
+      self = this;
+    dynamic v;
+    v = let final self::Class #t83 = super.{self::Class::[]}(this) in #t83 == null ?{self::Class} let final void #t84 = super.{self::Class::[]=}(this, this) in this : #t83;
+    v = let final self::Class #t85 = self in let final self::Class #t86 = super.{self::Class::[]}(#t85) in #t86 == null ?{self::Class} let final self::Class #t87 = self in let final void #t88 = super.{self::Class::[]=}(#t85, #t87) in #t87 : #t86;
+    v = let final void #t89 = super.{self::Class::[]=}(this, this) in this;
+    v = let final self::Class #t90 = self in let final self::Class #t91 = self in let final void #t92 = super.{self::Class::[]=}(#t90, #t91) in #t91;
+    v = super.{self::Class::[]}(this);
+    v = super.{self::Class::[]}(self);
+    v = let final self::Class #t93 = super.{self::Class::[]}(this).{self::Class::+}(this){(self::Class) → self::Class} in let final void #t94 = super.{self::Class::[]=}(this, #t93) in #t93;
+    v = let final self::Class #t95 = self in let final self::Class #t96 = super.{self::Class::[]}(#t95).{self::Class::+}(self){(self::Class) → self::Class} in let final void #t97 = super.{self::Class::[]=}(#t95, #t96) in #t96;
+  }
+}
+class Class2 extends core::Object {
+  synthetic constructor •() → self::Class2
+    : super core::Object::•()
+    ;
+  operator +(self::Class2 cls) → self::Class2
+    return cls;
+  method implicitExtensionGetSetForEffect() → void {
+    late final self::Class2 self;
+    if(self::b)
+      self = this;
+    self::Extension2|[](this, this) == null ?{self::Class2} self::Extension2|[]=(this, this, this) : null;
+    let final self::Class2 #t98 = self in let final self::Class2 #t99 = self in self::Extension2|[](#t98, #t99) == null ?{self::Class2} self::Extension2|[]=(#t98, #t99, self) : null;
+    self::Extension2|[]=(this, this, this);
+    self::Extension2|[]=(self, self, self);
+    self::Extension2|[](this, this);
+    self::Extension2|[](self, self);
+    self::Extension2|[]=(this, this, self::Extension2|[](this, this).{self::Class2::+}(this){(self::Class2) → self::Class2});
+    let final self::Class2 #t100 = self in let final self::Class2 #t101 = self in self::Extension2|[]=(#t100, #t101, self::Extension2|[](#t100, #t101).{self::Class2::+}(self){(self::Class2) → self::Class2});
+  }
+  method implicitExtensionGetSetForValue() → void {
+    late final self::Class2 self;
+    if(self::b)
+      self = this;
+    dynamic v;
+    v = let final self::Class2 #t102 = self::Extension2|[](this, this) in #t102 == null ?{self::Class2} let final void #t103 = self::Extension2|[]=(this, this, this) in this : #t102;
+    v = let final self::Class2 #t104 = self in let final self::Class2 #t105 = self in let final self::Class2 #t106 = self::Extension2|[](#t104, #t105) in #t106 == null ?{self::Class2} let final self::Class2 #t107 = self in let final void #t108 = self::Extension2|[]=(#t104, #t105, #t107) in #t107 : #t106;
+    v = let final void #t109 = self::Extension2|[]=(this, this, this) in this;
+    v = let final self::Class2 #t110 = self in let final self::Class2 #t111 = self in let final self::Class2 #t112 = self in let final void #t113 = self::Extension2|[]=(#t110, #t111, #t112) in #t112;
+    v = self::Extension2|[](this, this);
+    v = self::Extension2|[](self, self);
+    v = let final self::Class2 #t114 = self::Extension2|[](this, this).{self::Class2::+}(this){(self::Class2) → self::Class2} in let final void #t115 = self::Extension2|[]=(this, this, #t114) in #t114;
+    v = let final self::Class2 #t116 = self in let final self::Class2 #t117 = self in let final self::Class2 #t118 = self::Extension2|[](#t116, #t117).{self::Class2::+}(self){(self::Class2) → self::Class2} in let final void #t119 = self::Extension2|[]=(#t116, #t117, #t118) in #t118;
+  }
+  method explicitExtensionGetSetForEffect() → void {
+    late final self::Class2 self;
+    if(self::b)
+      self = this;
+    self::Extension2|[](this, this) == null ?{self::Class2} self::Extension2|[]=(this, this, this) : null;
+    let final self::Class2 #t120 = self in let final self::Class2 #t121 = self in self::Extension2|[](#t120, #t121) == null ?{self::Class2} self::Extension2|[]=(#t120, #t121, self) : null;
+    self::Extension2|[]=(this, this, this);
+    self::Extension2|[]=(self, self, self);
+    self::Extension2|[](this, this);
+    self::Extension2|[](self, self);
+    self::Extension2|[]=(this, this, self::Extension2|[](this, this).{self::Class2::+}(this){(self::Class2) → self::Class2});
+    let final self::Class2 #t122 = self in let final self::Class2 #t123 = self in self::Extension2|[]=(#t122, #t123, self::Extension2|[](#t122, #t123).{self::Class2::+}(self){(self::Class2) → self::Class2});
+  }
+  method explicitExtensionGetSetForValue() → void {
+    late final self::Class2 self;
+    if(self::b)
+      self = this;
+    dynamic v;
+    v = let final self::Class2 #t124 = self::Extension2|[](this, this) in #t124 == null ?{self::Class2} let final void #t125 = self::Extension2|[]=(this, this, this) in this : #t124;
+    v = let final self::Class2 #t126 = self in let final self::Class2 #t127 = self in let final self::Class2 #t128 = self::Extension2|[](#t126, #t127) in #t128 == null ?{self::Class2} let final self::Class2 #t129 = self in let final void #t130 = self::Extension2|[]=(#t126, #t127, #t129) in #t129 : #t128;
+    v = let final void #t131 = self::Extension2|[]=(this, this, this) in this;
+    v = let final self::Class2 #t132 = self in let final self::Class2 #t133 = self in let final void #t134 = self::Extension2|[]=(#t132, self, #t133) in #t133;
+    v = self::Extension2|[](this, this);
+    v = self::Extension2|[](self, self);
+    v = let final self::Class2 #t135 = self::Extension2|[](this, this).{self::Class2::+}(this){(self::Class2) → self::Class2} in let final void #t136 = self::Extension2|[]=(this, this, #t135) in #t135;
+    v = let final self::Class2 #t137 = self in let final self::Class2 #t138 = self in let final self::Class2 #t139 = self::Extension2|[](#t137, #t138).{self::Class2::+}(self){(self::Class2) → self::Class2} in let final void #t140 = self::Extension2|[]=(#t137, #t138, #t139) in #t139;
+  }
+}
+extension Extension on core::int {
+  operator [] = self::Extension|[];
+  operator []= = self::Extension|[]=;
+}
+extension Extension2 on self::Class2 {
+  operator [] = self::Extension2|[];
+  operator []= = self::Extension2|[]=;
+}
+static field core::bool b = true;
+static method Extension|[](lowered final core::int #this, self::Class cls) → self::Class
+  return new self::Class::•();
+static method Extension|[]=(lowered final core::int #this, self::Class cls, self::Class value) → void {}
+static method Extension2|[](lowered final self::Class2 #this, self::Class2 cls) → self::Class2
+  return new self::Class2::•();
+static method Extension2|[]=(lowered final self::Class2 #this, self::Class2 cls, self::Class2 value) → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/redundant_type_casts.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/redundant_type_casts.dart.weak.modular.expect
new file mode 100644
index 0000000..1062bac
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/redundant_type_casts.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object? = dynamic> extends core::Object {
+  covariant-by-class field self::A::T? _current = null;
+  synthetic constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+  get current() → self::A::T%
+    return this.{self::A::_current}{self::A::T?} as{ForNonNullableByDefault} self::A::T%;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/required.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/required.dart.weak.modular.expect
new file mode 100644
index 0000000..ccce283
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/required.dart.weak.modular.expect
@@ -0,0 +1,105 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/required.dart:29:8: Error: The parameter 'x' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   foo({x}) {}
+//        ^
+//
+// pkg/front_end/testcases/nnbd/required.dart:51:18: Error: Non-optional parameters can't have a default value.
+// Try removing the default value or making the parameter optional.
+//   Function(int a = 42, [int b]) f2;
+//                  ^
+//
+// pkg/front_end/testcases/nnbd/required.dart:52:17: Error: Non-optional parameters can't have a default value.
+// Try removing the default value or making the parameter optional.
+//   void g2(int a = 42, [int b]) {}
+//                 ^
+//
+// pkg/front_end/testcases/nnbd/required.dart:53:15: Error: Non-optional parameters can't have a default value.
+// Try removing the default value or making the parameter optional.
+//   f2 = (int a = 42, [int b]) {};
+//               ^
+//
+// pkg/front_end/testcases/nnbd/required.dart:48:15: Error: The parameter 'a' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   void g({int a, required int b = 42}) {}
+//               ^
+//
+// pkg/front_end/testcases/nnbd/required.dart:48:31: Error: Named parameter 'b' is required and can't have a default value.
+//   void g({int a, required int b = 42}) {}
+//                               ^
+//
+// pkg/front_end/testcases/nnbd/required.dart:49:13: Error: The parameter 'a' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   f = ({int a, required int b = 42}) {};
+//             ^
+//
+// pkg/front_end/testcases/nnbd/required.dart:49:29: Error: Named parameter 'b' is required and can't have a default value.
+//   f = ({int a, required int b = 42}) {};
+//                             ^
+//
+// pkg/front_end/testcases/nnbd/required.dart:52:28: Error: The parameter 'b' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   void g2(int a = 42, [int b]) {}
+//                            ^
+//
+// pkg/front_end/testcases/nnbd/required.dart:53:26: Error: The parameter 'b' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   f2 = (int a = 42, [int b]) {};
+//                          ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef Typedef1 = ({a: core::int, required b: core::int}) → dynamic;
+typedef Typedef2 = ({a: core::int, required b: core::int}) → dynamic;
+class Class extends core::Object {
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  method method({core::int a = #C1, required core::int b = #C2, required final core::int c = #C2, required covariant-by-declaration final core::int d = #C2}) → dynamic {}
+}
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  abstract method foo({core::int x = #C2}) → dynamic;
+}
+class B extends self::A {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+  method foo({core::int x = #C2}) → dynamic {}
+}
+class C extends self::A {
+  synthetic constructor •() → self::C
+    : super self::A::•()
+    ;
+  method foo({core::int x = #C1}) → dynamic {}
+}
+static field ({a: core::int, required b: core::int}) → dynamic field = ({core::int a = #C1, required core::int b = #C2}) → Null {};
+static method method({core::int a = #C1, required core::int b = #C2, required final core::int c = #C2}) → dynamic {}
+static method ok() → dynamic {
+  ({a: core::int, required b: core::int}) → dynamic f;
+  function g({core::int a = #C1, required core::int b = #C2}) → void {}
+  f = ({core::int a = #C1, required core::int b = #C2}) → Null {};
+  (core::int, [core::int]) → dynamic f2;
+  function g2(core::int a, [core::int b = #C1]) → void {}
+  f2 = (core::int a, [core::int b = #C1]) → Null {};
+}
+static method error() → dynamic {
+  ({a: core::int, required b: core::int}) → dynamic f;
+  function g({core::int a = #C2, required core::int b = #C1}) → void {}
+  f = ({core::int a = #C2, required core::int b = #C1}) → Null {};
+  (core::int, [core::int]) → dynamic f2;
+  function g2(core::int a = #C1, [core::int b = #C2]) → void {}
+  f2 = (core::int a = #C1, [core::int b = #C2]) → Null {};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 42
+  #C2 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/required_named_parameter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/required_named_parameter.dart.weak.modular.expect
new file mode 100644
index 0000000..0f14fea
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/required_named_parameter.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/required_named_parameter.dart:6:19: Error: Named parameter 'parameter' is required and can't have a default value.
+// foo({required int parameter = 42}) {}
+//                   ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/required_named_parameter.dart:7:11: Error: The parameter 'parameter' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// foo2({int parameter}) {}
+//           ^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd/required_named_parameter.dart:8:11: Error: The parameter 'parameter' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+// foo3([int parameter]) {}
+//           ^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method foo({required core::int parameter = #C1}) → dynamic {}
+static method foo2({core::int parameter = #C2}) → dynamic {}
+static method foo3([core::int parameter = #C2]) → dynamic {}
+static method bar({required core::int parameter = #C2}) → dynamic {}
+static method bar2({core::int parameter = #C1}) → dynamic {}
+static method bar3([core::int parameter = #C1]) → dynamic {}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 42
+  #C2 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/return_async.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/return_async.dart.weak.modular.expect
new file mode 100644
index 0000000..ce2f50d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/return_async.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "dart:async";
+
+static method throwSync() → asy::Future<void> {
+  throw "";
+}
+static method allYield() → asy::Future<void> async {
+  await 0;
+  await self::allYield2();
+}
+static method allYield2() → asy::Future<void> async {
+  await 0;
+  await self::allYield3();
+}
+static method allYield3() → asy::Future<void> async {
+  await 0;
+  self::throwSync();
+}
+static method customErrorZone() → asy::Future<void> async {
+  final asy::Completer<void> completer = asy::Completer::•<void>();
+  asy::runZonedGuarded<asy::Future<Null>>(() → asy::Future<Null> async {
+    await self::allYield();
+    completer.{asy::Completer::complete}(null){([FutureOr<void>?]) → void};
+  }, (core::Object e, core::StackTrace s) → void {
+    completer.{asy::Completer::completeError}(e, s){(core::Object, [core::StackTrace?]) → void};
+  });
+  return completer.{asy::Completer::future}{asy::Future<void>};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/return_late.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/return_late.dart.weak.modular.expect
new file mode 100644
index 0000000..e58813e
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/return_late.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Class<E extends core::Object? = dynamic> extends core::Object {
+  final field self::Class::E% field;
+  constructor •(self::Class::E% field) → self::Class<self::Class::E%>
+    : self::Class::field = field, super core::Object::•()
+    ;
+  method returnTypeVariable() → self::Class::E% {
+    late self::Class::E% result = this.{self::Class::field}{self::Class::E%};
+    return result;
+  }
+}
+static method returnNonNullable(core::int value) → core::int {
+  late core::int result = value;
+  return result;
+}
+static method returnNullable(core::int? value) → core::int? {
+  late core::int? result = value;
+  return result;
+}
+static method main() → dynamic {
+  self::expect(42, new self::Class::•<core::int>(42).{self::Class::returnTypeVariable}(){() → core::int});
+  self::expect(87, new self::Class::•<core::int?>(87).{self::Class::returnTypeVariable}(){() → core::int?});
+  self::expect(null, new self::Class::•<core::int?>(null).{self::Class::returnTypeVariable}(){() → core::int?});
+  self::expect(42, self::returnNonNullable(42));
+  self::expect(87, self::returnNullable(87));
+  self::expect(null, self::returnNullable(null));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
diff --git a/pkg/front_end/testcases/nnbd/return_null.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/return_null.dart.weak.modular.expect
new file mode 100644
index 0000000..8c3d6c3
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/return_null.dart.weak.modular.expect
@@ -0,0 +1,244 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/return_null.dart:7:8: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+// String returnImplicit() /*error*/ {
+//        ^
+//
+// pkg/front_end/testcases/nnbd/return_null.dart:13:10: Error: The value 'null' can't be returned from a function with return type 'String' because 'String' is not nullable.
+//   return null; // error
+//          ^
+//
+// pkg/front_end/testcases/nnbd/return_null.dart:19:12: Error: The value 'null' can't be returned from a function with return type 'String' because 'String' is not nullable.
+//     return null; // error
+//            ^
+//
+// pkg/front_end/testcases/nnbd/return_null.dart:16:8: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+// String returnMixed(bool b) /*error*/ {
+//        ^
+//
+// pkg/front_end/testcases/nnbd/return_null.dart:27:15: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+// FutureOr<int> returnAsync3() async {} // error
+//               ^
+//
+// pkg/front_end/testcases/nnbd/return_null.dart:54:6: Error: A non-null value must be returned since the return type 'Enum' doesn't allow null.
+//  - 'Enum' is from 'pkg/front_end/testcases/nnbd/return_null.dart'.
+// Enum caseReturn2(Enum e) /* error */ {
+//      ^
+//
+// pkg/front_end/testcases/nnbd/return_null.dart:63:3: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+//   String returnImplicit() /* error */ {
+//   ^
+//
+// pkg/front_end/testcases/nnbd/return_null.dart:69:12: Error: The value 'null' can't be returned from a function with return type 'String' because 'String' is not nullable.
+//     return null; // error
+//            ^
+//
+// pkg/front_end/testcases/nnbd/return_null.dart:75:14: Error: The value 'null' can't be returned from a function with return type 'String' because 'String' is not nullable.
+//       return null; // error
+//              ^
+//
+// pkg/front_end/testcases/nnbd/return_null.dart:72:3: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+//   String returnMixed(bool b) /* error */ {
+//   ^
+//
+// pkg/front_end/testcases/nnbd/return_null.dart:83:3: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+//   FutureOr<int> returnAsync3() async {} // error
+//   ^
+//
+// pkg/front_end/testcases/nnbd/return_null.dart:108:3: Error: A non-null value must be returned since the return type 'Enum' doesn't allow null.
+//  - 'Enum' is from 'pkg/front_end/testcases/nnbd/return_null.dart'.
+//   Enum caseReturn2(Enum e) /* error */ {
+//   ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+import "dart:_internal" as _in;
+
+import "dart:async";
+
+class Enum extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::Enum> values = #C7;
+  static const field self::Enum a = #C3;
+  static const field self::Enum b = #C6;
+  const constructor •(core::int index, core::String name) → self::Enum
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String
+    return "Enum.${this.{core::_Enum::_name}{core::String}}";
+}
+static method returnImplicit() → core::String {
+  core::print("foo");
+  return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:7:8: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+String returnImplicit() /*error*/ {
+       ^" in null;
+}
+static method returnExplicit() → core::String {
+  core::print("foo");
+  return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:13:10: Error: The value 'null' can't be returned from a function with return type 'String' because 'String' is not nullable.
+  return null; // error
+         ^" in null as{TypeError,ForNonNullableByDefault} core::String;
+}
+static method returnMixed(core::bool b) → core::String {
+  if(b) {
+    core::print("foo");
+    return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:19:12: Error: The value 'null' can't be returned from a function with return type 'String' because 'String' is not nullable.
+    return null; // error
+           ^" in null as{TypeError,ForNonNullableByDefault} core::String;
+  }
+  return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:16:8: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+String returnMixed(bool b) /*error*/ {
+       ^" in null;
+}
+static method returnAsync1() → asy::Future<dynamic> async {}
+static method returnAsync2() → FutureOr<dynamic> async {}
+static method returnAsync3() → FutureOr<core::int> async {
+  return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:27:15: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+FutureOr<int> returnAsync3() async {} // error
+              ^" in null;
+}
+static method returnAsync4() → FutureOr<core::int?> async {}
+static method returnAsync5() → dynamic async {}
+static method returnAsync6() → asy::Future<core::int?> async {
+  return null;
+}
+static method returnAsync7() → asy::Future<core::int?> async {}
+static method yieldSync() → core::Iterable<dynamic> sync* {}
+static method yieldAsync() → asy::Stream<dynamic> async* {}
+static method caseReturn1(self::Enum e) → self::Enum {
+  switch(e) {
+    #L1:
+    case #C3:
+      {
+        return e;
+      }
+    #L2:
+    case #C6:
+      {
+        return e;
+      }
+    #L3:
+    default:
+      throw new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable enum type.");
+  }
+}
+static method caseReturn2(self::Enum e) → self::Enum {
+  switch(e) {
+    #L4:
+    case #C3:
+      {
+        return e;
+      }
+    #L5:
+    default:
+      {}
+  }
+  return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:54:6: Error: A non-null value must be returned since the return type 'Enum' doesn't allow null.
+ - 'Enum' is from 'pkg/front_end/testcases/nnbd/return_null.dart'.
+Enum caseReturn2(Enum e) /* error */ {
+     ^" in null;
+}
+static method localFunctions() → dynamic {
+  function returnImplicit() → core::String {
+    core::print("foo");
+    return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:63:3: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+  String returnImplicit() /* error */ {
+  ^" in null;
+  }
+  function returnExplicit() → core::String {
+    core::print("foo");
+    return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:69:12: Error: The value 'null' can't be returned from a function with return type 'String' because 'String' is not nullable.
+    return null; // error
+           ^" in null as{TypeError,ForNonNullableByDefault} core::String;
+  }
+  function returnMixed(core::bool b) → core::String {
+    if(b) {
+      core::print("foo");
+      return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:75:14: Error: The value 'null' can't be returned from a function with return type 'String' because 'String' is not nullable.
+      return null; // error
+             ^" in null as{TypeError,ForNonNullableByDefault} core::String;
+    }
+    return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:72:3: Error: A non-null value must be returned since the return type 'String' doesn't allow null.
+  String returnMixed(bool b) /* error */ {
+  ^" in null;
+  }
+  function returnAsync1() → asy::Future<dynamic> async {}
+  function returnAsync2() → FutureOr<dynamic> async {}
+  function returnAsync3() → FutureOr<core::int> async {
+    return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:83:3: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+  FutureOr<int> returnAsync3() async {} // error
+  ^" in null;
+  }
+  function returnAsync4() → FutureOr<core::int?> async {}
+  function returnAsync5() → asy::Future<Null> async {}
+  function returnAsync6() → asy::Future<core::int?> async {
+    return null;
+  }
+  function returnAsync7() → asy::Future<core::int?> async {}
+  function yieldSync() → core::Iterable<dynamic> sync* {}
+  function yieldAsync() → asy::Stream<dynamic> async* {}
+  function caseReturn1(self::Enum e) → self::Enum {
+    switch(e) {
+      #L6:
+      case #C3:
+        {
+          return e;
+        }
+      #L7:
+      case #C6:
+        {
+          return e;
+        }
+      #L8:
+      default:
+        throw new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable enum type.");
+    }
+  }
+  function caseReturn2(self::Enum e) → self::Enum {
+    switch(e) {
+      #L9:
+      case #C3:
+        {
+          return e;
+        }
+      #L10:
+      default:
+        {}
+    }
+    return invalid-expression "pkg/front_end/testcases/nnbd/return_null.dart:108:3: Error: A non-null value must be returned since the return type 'Enum' doesn't allow null.
+ - 'Enum' is from 'pkg/front_end/testcases/nnbd/return_null.dart'.
+  Enum caseReturn2(Enum e) /* error */ {
+  ^" in null;
+  }
+  core::bool b = false;
+  core::int? local1 = (() → core::int? {
+    if(b)
+      return 0;
+  })(){() → core::int?};
+  core::int? local2 = (() → core::int? {
+    if(b)
+      return null;
+    if(!b)
+      return 0;
+  })(){() → core::int?};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+  #C2 = "a"
+  #C3 = self::Enum {index:#C1, _name:#C2}
+  #C4 = 1
+  #C5 = "b"
+  #C6 = self::Enum {index:#C4, _name:#C5}
+  #C7 = <self::Enum*>[#C3, #C6]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///return_null.dart:
+- Enum. (from org-dartlang-testcase:///return_null.dart:43:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:76:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/shorting_null_check.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/shorting_null_check.dart.weak.modular.expect
new file mode 100644
index 0000000..a02071a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/shorting_null_check.dart.weak.modular.expect
@@ -0,0 +1,107 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/shorting_null_check.dart:12:24: Warning: Operand of null-aware operation '!' has type 'int' which excludes null.
+// int? test1(A? a) => a?.zero!;
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/shorting_null_check.dart:14:25: Warning: Operand of null-aware operation '!' has type 'int' which excludes null.
+// bool? test3(A? a) => a?.zero!.isEven;
+//                         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int zero;
+  field core::int? zeroOrNull;
+  constructor •(core::int zero, [core::int? zeroOrNull = #C1]) → self::A
+    : self::A::zero = zero, self::A::zeroOrNull = zeroOrNull, super core::Object::•()
+    ;
+}
+class Foo extends core::Object {
+  field self::Bar? bar;
+  constructor •(self::Bar? bar) → self::Foo
+    : self::Foo::bar = bar, super core::Object::•()
+    ;
+  operator [](core::int? index) → self::Bar?
+    return !(index == null) ?{self::Bar?} new self::Bar::•(index{core::int}) : null;
+}
+class Bar extends core::Object {
+  field core::int baz;
+  constructor •(core::int baz) → self::Bar
+    : self::Bar::baz = baz, super core::Object::•()
+    ;
+  operator [](core::int index) → core::int
+    return index;
+  operator ==(core::Object other) → core::bool
+    return other is{ForNonNullableByDefault} self::Bar && this.{self::Bar::baz}{core::int} =={core::num::==}{(core::Object) → core::bool} other{self::Bar}.{self::Bar::baz}{core::int};
+}
+static method test1(self::A? a) → core::int?
+  return let final self::A? #t1 = a in #t1 == null ?{core::int?} null : #t1{self::A}.{self::A::zero}{core::int}!;
+static method test2(self::A? a) → core::int?
+  return let final self::A? #t2 = a in #t2 == null ?{core::int?} null : #t2{self::A}.{self::A::zeroOrNull}{core::int?}!;
+static method test3(self::A? a) → core::bool?
+  return let final self::A? #t3 = a in #t3 == null ?{core::bool?} null : #t3{self::A}.{self::A::zero}{core::int}!.{core::int::isEven}{core::bool};
+static method test4(self::A? a) → core::bool?
+  return let final self::A? #t4 = a in #t4 == null ?{core::bool?} null : #t4{self::A}.{self::A::zeroOrNull}{core::int?}!.{core::int::isEven}{core::bool};
+static method test5(self::Foo? foo) → self::Bar?
+  return let final self::Foo? #t5 = foo in #t5 == null ?{self::Bar?} null : #t5{self::Foo}.{self::Foo::bar}{self::Bar?}!;
+static method test6(self::Foo? foo) → core::int?
+  return let final self::Foo? #t6 = foo in #t6 == null ?{core::int?} null : #t6{self::Foo}.{self::Foo::bar}{self::Bar?}!.{self::Bar::baz}{core::int};
+static method test7(self::Foo? foo, core::int baz) → core::int?
+  return let final self::Foo? #t7 = foo in #t7 == null ?{core::int?} null : #t7{self::Foo}.{self::Foo::bar}{self::Bar?}!.{self::Bar::[]}(baz){(core::int) → core::int};
+static method test8(self::Foo? foo, core::int? bar) → self::Bar?
+  return let final self::Foo? #t8 = foo in #t8 == null ?{self::Bar?} null : #t8{self::Foo}.{self::Foo::[]}(bar){(core::int?) → self::Bar?}!;
+static method test9(self::Foo? foo, core::int? bar) → core::int?
+  return let final self::Foo? #t9 = foo in #t9 == null ?{core::int?} null : #t9{self::Foo}.{self::Foo::[]}(bar){(core::int?) → self::Bar?}!.{self::Bar::baz}{core::int};
+static method test10(self::Foo? foo, core::int? bar, core::int baz) → dynamic
+  return let final self::Foo? #t10 = foo in #t10 == null ?{core::int?} null : #t10{self::Foo}.{self::Foo::[]}(bar){(core::int?) → self::Bar?}!.{self::Bar::[]}(baz){(core::int) → core::int};
+static method main() → dynamic {
+  self::expect(0, self::test1(new self::A::•(0)));
+  self::expect(null, self::test1(null));
+  self::expect(0, self::test2(new self::A::•(0, 0)));
+  self::expect(null, self::test2(null));
+  self::throws(() → void => self::test2(new self::A::•(0, null)));
+  self::expect(true, self::test3(new self::A::•(0)));
+  self::expect(null, self::test3(null));
+  self::expect(true, self::test4(new self::A::•(0, 0)));
+  self::expect(null, self::test4(null));
+  self::throws(() → void => self::test4(new self::A::•(0, null)));
+  self::expect(new self::Bar::•(0), self::test5(new self::Foo::•(new self::Bar::•(0))));
+  self::expect(null, self::test5(null));
+  self::throws(() → void => self::test5(new self::Foo::•(null)));
+  self::expect(0, self::test6(new self::Foo::•(new self::Bar::•(0))));
+  self::expect(null, self::test6(null));
+  self::throws(() → void => self::test6(new self::Foo::•(null)));
+  self::expect(42, self::test7(new self::Foo::•(new self::Bar::•(0)), 42));
+  self::expect(null, self::test7(null, 42));
+  self::throws(() → void => self::test7(new self::Foo::•(null), 42));
+  self::expect(new self::Bar::•(42), self::test8(new self::Foo::•(new self::Bar::•(0)), 42));
+  self::expect(null, self::test8(null, 42));
+  self::throws(() → void => self::test8(new self::Foo::•(new self::Bar::•(0)), null));
+  self::expect(42, self::test9(new self::Foo::•(new self::Bar::•(0)), 42));
+  self::expect(null, self::test9(null, 42));
+  self::throws(() → void => self::test9(new self::Foo::•(new self::Bar::•(0)), null));
+  self::expect(87, self::test10(new self::Foo::•(new self::Bar::•(0)), 42, 87));
+  self::expect(null, self::test10(null, 42, 87));
+  self::throws(() → void => self::test10(new self::Foo::•(new self::Bar::•(0)), null, 87));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → void f) → dynamic {
+  try {
+    f(){() → void};
+  }
+  on core::Object catch(final core::Object _) {
+    return;
+  }
+  throw "Missing exception";
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/shorting_stop.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/shorting_stop.dart.weak.modular.expect
new file mode 100644
index 0000000..0e34446
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/shorting_stop.dart.weak.modular.expect
@@ -0,0 +1,113 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/shorting_stop.dart:18:33: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+//   throwsInStrong(() => c?.field + 2); // error
+//                                 ^
+//
+// pkg/front_end/testcases/nnbd/shorting_stop.dart:21:34: Error: Property 'field' cannot be accessed on 'Class?' because it is potentially null.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd/shorting_stop.dart'.
+// Try accessing using ?. instead.
+//   throwsInStrong(() => (c?.next).field); // error
+//                                  ^^^^^
+//
+// pkg/front_end/testcases/nnbd/shorting_stop.dart:22:24: Error: Operator 'unary-' cannot be called on 'int?' because it is potentially null.
+//   throwsInStrong(() => -c?.field); // error
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/shorting_stop.dart:25:35: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+//   throwsInStrong(() => c?.next[0] + 2); // error
+//                                   ^
+//
+// pkg/front_end/testcases/nnbd/shorting_stop.dart:28:37: Error: Property 'isEven' cannot be accessed on 'int?' because it is potentially null.
+// Try accessing using ?. instead.
+//   throwsInStrong(() => (c?.next[0]).isEven); // error
+//                                     ^^^^^^
+//
+// pkg/front_end/testcases/nnbd/shorting_stop.dart:29:24: Error: Operator 'unary-' cannot be called on 'int?' because it is potentially null.
+//   throwsInStrong(() => -c?.next[0]); // error
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/shorting_stop.dart:36:7: Error: Property 'length' cannot be accessed on 'String?' because it is potentially null.
+// Try accessing using ?. instead.
+//     s.length; // This will be an invalid expression in strong mode.
+//       ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int field = 0;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  get next() → self::Class
+    return this;
+  operator [](core::int key) → core::int
+    return key;
+  operator []=(core::int key, core::int value) → void {}
+}
+static final field core::bool inStrongMode = self::_inStrongMode();
+static method main() → dynamic {
+  self::test(new self::Class::•());
+}
+static method test(self::Class? c) → dynamic {
+  let final self::Class? #t1 = c in #t1 == null ?{core::int?} null : #t1{self::Class}.{self::Class::next}{self::Class}.{self::Class::field}{core::int};
+  self::throwsInStrong(() → void => invalid-expression "pkg/front_end/testcases/nnbd/shorting_stop.dart:18:33: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+  throwsInStrong(() => c?.field + 2); // error
+                                ^" in (let final self::Class? #t2 = c in #t2 == null ?{core::int?} null : #t2{self::Class}.{self::Class::field}{core::int}).{core::num::+}(2){(core::num) → core::num});
+  let final self::Class? #t3 = c in #t3 == null ?{core::int?} null : let final core::int #t4 = #t3.{self::Class::field}{core::int}.{core::num::+}(1){(core::num) → core::int} in let final void #t5 = #t3.{self::Class::field} = #t4 in #t4;
+  let final self::Class? #t6 = c in #t6 == null ?{core::int?} null : #t6.{self::Class::field} = #t6.{self::Class::field}{core::int}.{core::num::+}(1){(core::num) → core::int};
+  self::throwsInStrong(() → void => invalid-expression "pkg/front_end/testcases/nnbd/shorting_stop.dart:21:34: Error: Property 'field' cannot be accessed on 'Class?' because it is potentially null.
+ - 'Class' is from 'pkg/front_end/testcases/nnbd/shorting_stop.dart'.
+Try accessing using ?. instead.
+  throwsInStrong(() => (c?.next).field); // error
+                                 ^^^^^" in (let final self::Class? #t7 = c in #t7 == null ?{self::Class?} null : #t7{self::Class}.{self::Class::next}{self::Class}).{self::Class::field}{<nullable>}.{core::int});
+  self::throwsInStrong(() → void => invalid-expression "pkg/front_end/testcases/nnbd/shorting_stop.dart:22:24: Error: Operator 'unary-' cannot be called on 'int?' because it is potentially null.
+  throwsInStrong(() => -c?.field); // error
+                       ^" in (let final self::Class? #t8 = c in #t8 == null ?{core::int?} null : #t8{self::Class}.{self::Class::field}{core::int}).{core::int::unary-}(){() → core::int});
+  let final self::Class? #t9 = c in #t9 == null ?{core::bool?} null : #t9{self::Class}.{self::Class::next}{self::Class}.{self::Class::[]}(0){(core::int) → core::int}.{core::int::isEven}{core::bool};
+  self::throwsInStrong(() → void => invalid-expression "pkg/front_end/testcases/nnbd/shorting_stop.dart:25:35: Error: Operator '+' cannot be called on 'int?' because it is potentially null.
+  throwsInStrong(() => c?.next[0] + 2); // error
+                                  ^" in (let final self::Class? #t10 = c in #t10 == null ?{core::int?} null : #t10{self::Class}.{self::Class::next}{self::Class}.{self::Class::[]}(0){(core::int) → core::int}).{core::num::+}(2){(core::num) → core::num});
+  let final self::Class? #t11 = c in #t11 == null ?{core::int?} null : let final self::Class #t12 = #t11{self::Class}.{self::Class::next}{self::Class} in let final core::int #t13 = 0 in let final core::int #t14 = #t12.{self::Class::[]}(#t13){(core::int) → core::int}.{core::num::+}(1){(core::num) → core::int} in let final void #t15 = #t12.{self::Class::[]=}(#t13, #t14){(core::int, core::int) → void} in #t14;
+  let final self::Class? #t16 = c in #t16 == null ?{core::int?} null : let final self::Class #t17 = #t16{self::Class}.{self::Class::next}{self::Class} in let final core::int #t18 = 0 in #t17.{self::Class::[]=}(#t18, #t17.{self::Class::[]}(#t18){(core::int) → core::int}.{core::num::+}(1){(core::num) → core::int}){(core::int, core::int) → void};
+  self::throwsInStrong(() → void => invalid-expression "pkg/front_end/testcases/nnbd/shorting_stop.dart:28:37: Error: Property 'isEven' cannot be accessed on 'int?' because it is potentially null.
+Try accessing using ?. instead.
+  throwsInStrong(() => (c?.next[0]).isEven); // error
+                                    ^^^^^^" in (let final self::Class? #t19 = c in #t19 == null ?{core::int?} null : #t19{self::Class}.{self::Class::next}{self::Class}.{self::Class::[]}(0){(core::int) → core::int}).{core::int::isEven}{<nullable>}.{core::bool});
+  self::throwsInStrong(() → void => invalid-expression "pkg/front_end/testcases/nnbd/shorting_stop.dart:29:24: Error: Operator 'unary-' cannot be called on 'int?' because it is potentially null.
+  throwsInStrong(() => -c?.next[0]); // error
+                       ^" in (let final self::Class? #t20 = c in #t20 == null ?{core::int?} null : #t20{self::Class}.{self::Class::next}{self::Class}.{self::Class::[]}(0){(core::int) → core::int}).{core::int::unary-}(){() → core::int});
+}
+static method _inStrongMode() → core::bool {
+  (core::String?) → Null f = (core::String? s) → Null {
+    invalid-expression "pkg/front_end/testcases/nnbd/shorting_stop.dart:36:7: Error: Property 'length' cannot be accessed on 'String?' because it is potentially null.
+Try accessing using ?. instead.
+    s.length; // This will be an invalid expression in strong mode.
+      ^^^^^^" in s.{core::String::length}{<nullable>}.{core::int};
+  };
+  try {
+    f("foo"){(core::String?) → Null};
+  }
+  on core::Object catch(final core::Object e) {
+    return true;
+  }
+  return false;
+}
+static method throwsInStrong(() → void f) → void {
+  if(self::inStrongMode) {
+    try {
+      f(){() → void};
+    }
+    on core::Object catch(final core::Object e) {
+      core::print(e);
+      return;
+    }
+    throw "Expected exception.";
+  }
+  else {
+    f(){() → void};
+  }
+}
diff --git a/pkg/front_end/testcases/nnbd/simple_never.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/simple_never.dart.weak.modular.expect
new file mode 100644
index 0000000..7047a3b
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/simple_never.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+
+static method foo() → Never {
+  while (true) {
+  }
+}
+static method bar() → Never?
+  return null;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/spread_if_null.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/spread_if_null.dart.weak.modular.expect
new file mode 100644
index 0000000..14bef22c5
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/spread_if_null.dart.weak.modular.expect
@@ -0,0 +1,142 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+static method main() → dynamic {
+  core::List<core::int>? list = null;
+  core::print( block {
+    final core::List<core::int> #t1 = <core::int>[1, 2];
+    final core::Iterable<core::int>? #t2 = list;
+    if(!(#t2 == null))
+      #t1.{core::List::addAll}{Invariant}(#t2{core::Iterable<core::int>}){(core::Iterable<core::int>) → void};
+    #t1.{core::List::add}{Invariant}(3){(core::int) → void};
+  } =>#t1);
+  core::print( block {
+    final core::List<core::int> #t3 = <core::int>[1, 2];
+    final core::Iterable<core::int>? #t4 = null;
+    if(!(#t4 == null))
+      #t3.{core::List::addAll}{Invariant}(#t4{core::Iterable<core::int>}){(core::Iterable<core::int>) → void};
+    #t3.{core::List::add}{Invariant}(3){(core::int) → void};
+  } =>#t3);
+  core::List<core::int> list1 = block {
+    final core::List<core::int> #t5 = <core::int>[];
+    final core::Iterable<core::int>? #t6 = list;
+    if(!(#t6 == null))
+      #t5.{core::List::addAll}{Invariant}(#t6{core::Iterable<core::int>}){(core::Iterable<core::int>) → void};
+  } =>#t5;
+  core::List<Never> list2 = block {
+    final core::List<Never> #t7 = <Never>[];
+    final core::Iterable<Never>? #t8 = null;
+    if(!(#t8 == null))
+      #t7.{core::List::addAll}{Invariant}(#t8{core::Iterable<Never>}){(core::Iterable<Never>) → void};
+  } =>#t7;
+  core::List<core::int> list3 = block {
+    final core::List<core::int> #t9 = <core::int>[1, 2];
+    final core::Iterable<core::int>? #t10 = list;
+    if(!(#t10 == null))
+      #t9.{core::List::addAll}{Invariant}(#t10{core::Iterable<core::int>}){(core::Iterable<core::int>) → void};
+    #t9.{core::List::add}{Invariant}(3){(core::int) → void};
+  } =>#t9;
+  core::List<core::int> list4 = block {
+    final core::List<core::int> #t11 = <core::int>[1, 2];
+    final core::Iterable<core::int>? #t12 = null;
+    if(!(#t12 == null))
+      #t11.{core::List::addAll}{Invariant}(#t12{core::Iterable<core::int>}){(core::Iterable<core::int>) → void};
+    #t11.{core::List::add}{Invariant}(3){(core::int) → void};
+  } =>#t11;
+  core::Set<core::int>? set = null;
+  core::print( block {
+    final core::Set<core::int> #t13 = col::LinkedHashSet::•<core::int>();
+    #t13.{core::Set::add}{Invariant}(1){(core::int) → core::bool};
+    #t13.{core::Set::add}{Invariant}(2){(core::int) → core::bool};
+    final core::Iterable<core::int>? #t14 = set;
+    if(!(#t14 == null))
+      #t13.{core::Set::addAll}{Invariant}(#t14{core::Iterable<core::int>}){(core::Iterable<core::int>) → void};
+    #t13.{core::Set::add}{Invariant}(3){(core::int) → core::bool};
+  } =>#t13);
+  core::print( block {
+    final core::Set<core::int> #t15 = col::LinkedHashSet::•<core::int>();
+    #t15.{core::Set::add}{Invariant}(1){(core::int) → core::bool};
+    #t15.{core::Set::add}{Invariant}(2){(core::int) → core::bool};
+    final core::Iterable<core::int>? #t16 = null;
+    if(!(#t16 == null))
+      #t15.{core::Set::addAll}{Invariant}(#t16{core::Iterable<core::int>}){(core::Iterable<core::int>) → void};
+    #t15.{core::Set::add}{Invariant}(3){(core::int) → core::bool};
+  } =>#t15);
+  core::Set<core::int> set1 = block {
+    final core::Set<core::int> #t17 = col::LinkedHashSet::•<core::int>();
+    final core::Iterable<dynamic>? #t18 = set;
+    if(!(#t18 == null))
+      for (final dynamic #t19 in #t18{core::Iterable<dynamic>}) {
+        final core::int #t20 = #t19 as{TypeError,ForNonNullableByDefault} core::int;
+        #t17.{core::Set::add}{Invariant}(#t20){(core::int) → core::bool};
+      }
+  } =>#t17;
+  core::Set<core::int> set3 = block {
+    final core::Set<core::int> #t21 = col::LinkedHashSet::•<core::int>();
+    #t21.{core::Set::add}{Invariant}(1){(core::int) → core::bool};
+    #t21.{core::Set::add}{Invariant}(2){(core::int) → core::bool};
+    final core::Iterable<core::int>? #t22 = set;
+    if(!(#t22 == null))
+      #t21.{core::Set::addAll}{Invariant}(#t22{core::Iterable<core::int>}){(core::Iterable<core::int>) → void};
+    #t21.{core::Set::add}{Invariant}(3){(core::int) → core::bool};
+  } =>#t21;
+  core::Set<core::int> set4 = block {
+    final core::Set<core::int> #t23 = col::LinkedHashSet::•<core::int>();
+    #t23.{core::Set::add}{Invariant}(1){(core::int) → core::bool};
+    #t23.{core::Set::add}{Invariant}(2){(core::int) → core::bool};
+    final core::Iterable<core::int>? #t24 = null;
+    if(!(#t24 == null))
+      #t23.{core::Set::addAll}{Invariant}(#t24{core::Iterable<core::int>}){(core::Iterable<core::int>) → void};
+    #t23.{core::Set::add}{Invariant}(3){(core::int) → core::bool};
+  } =>#t23;
+  core::Map<core::int, core::int>? map = null;
+  core::print( block {
+    final core::Map<core::int, core::int> #t25 = <core::int, core::int>{};
+    #t25.{core::Map::[]=}{Invariant}(1, 1){(core::int, core::int) → void};
+    #t25.{core::Map::[]=}{Invariant}(2, 2){(core::int, core::int) → void};
+    final core::Map<core::int, core::int>? #t26 = map;
+    if(!(#t26 == null))
+      for (final core::MapEntry<core::int, core::int> #t27 in #t26{core::Map<core::int, core::int>}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int, core::int>>})
+        #t25.{core::Map::[]=}{Invariant}(#t27.{core::MapEntry::key}{core::int}, #t27.{core::MapEntry::value}{core::int}){(core::int, core::int) → void};
+    #t25.{core::Map::[]=}{Invariant}(3, 3){(core::int, core::int) → void};
+  } =>#t25);
+  core::print( block {
+    final core::Map<core::int, core::int> #t28 = <core::int, core::int>{};
+    #t28.{core::Map::[]=}{Invariant}(1, 1){(core::int, core::int) → void};
+    #t28.{core::Map::[]=}{Invariant}(2, 2){(core::int, core::int) → void};
+    final core::Map<core::int, core::int>? #t29 = null;
+    if(!(#t29 == null))
+      for (final core::MapEntry<core::int, core::int> #t30 in #t29{core::Map<core::int, core::int>}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int, core::int>>})
+        #t28.{core::Map::[]=}{Invariant}(#t30.{core::MapEntry::key}{core::int}, #t30.{core::MapEntry::value}{core::int}){(core::int, core::int) → void};
+    #t28.{core::Map::[]=}{Invariant}(3, 3){(core::int, core::int) → void};
+  } =>#t28);
+  core::Map<core::int, core::int> map1 = block {
+    final core::Map<core::int, core::int> #t31 = <core::int, core::int>{};
+    final core::Map<core::int, core::int>? #t32 = map;
+    if(!(#t32 == null))
+      for (final core::MapEntry<core::int, core::int> #t33 in #t32{core::Map<core::int, core::int>}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int, core::int>>})
+        #t31.{core::Map::[]=}{Invariant}(#t33.{core::MapEntry::key}{core::int}, #t33.{core::MapEntry::value}{core::int}){(core::int, core::int) → void};
+  } =>#t31;
+  core::Map<core::int, core::int> map3 = block {
+    final core::Map<core::int, core::int> #t34 = <core::int, core::int>{};
+    #t34.{core::Map::[]=}{Invariant}(1, 1){(core::int, core::int) → void};
+    #t34.{core::Map::[]=}{Invariant}(2, 2){(core::int, core::int) → void};
+    final core::Map<core::int, core::int>? #t35 = map;
+    if(!(#t35 == null))
+      for (final core::MapEntry<core::int, core::int> #t36 in #t35{core::Map<core::int, core::int>}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int, core::int>>})
+        #t34.{core::Map::[]=}{Invariant}(#t36.{core::MapEntry::key}{core::int}, #t36.{core::MapEntry::value}{core::int}){(core::int, core::int) → void};
+    #t34.{core::Map::[]=}{Invariant}(3, 3){(core::int, core::int) → void};
+  } =>#t34;
+  core::Map<core::int, core::int> map4 = block {
+    final core::Map<core::int, core::int> #t37 = <core::int, core::int>{};
+    #t37.{core::Map::[]=}{Invariant}(1, 1){(core::int, core::int) → void};
+    #t37.{core::Map::[]=}{Invariant}(2, 2){(core::int, core::int) → void};
+    final core::Map<core::int, core::int>? #t38 = null;
+    if(!(#t38 == null))
+      for (final core::MapEntry<core::int, core::int> #t39 in #t38{core::Map<core::int, core::int>}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int, core::int>>})
+        #t37.{core::Map::[]=}{Invariant}(#t39.{core::MapEntry::key}{core::int}, #t39.{core::MapEntry::value}{core::int}){(core::int, core::int) → void};
+    #t37.{core::Map::[]=}{Invariant}(3, 3){(core::int, core::int) → void};
+  } =>#t37;
+}
diff --git a/pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart.weak.modular.expect
new file mode 100644
index 0000000..c211559
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart.weak.modular.expect
@@ -0,0 +1,191 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:22:10: Warning: Operand of null-aware operation '??=' has type 'String' which excludes null.
+//     super[42] ??= "bar"; // Warning.
+//          ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:27:3: Warning: Operand of null-aware operation '?.' has type 'String' which excludes null.
+//   s?.length; // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:28:3: Warning: Operand of null-aware operation '?..' has type 'String' which excludes null.
+//   s?..length; // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:29:3: Warning: Operand of null-aware operation '??' has type 'String' which excludes null.
+//   s ?? "foo"; // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:30:3: Warning: Operand of null-aware operation '??=' has type 'String' which excludes null.
+//   s ??= "foo"; // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:31:8: Warning: Operand of null-aware operation '...?' has type 'List<String>' which excludes null.
+//  - 'List' is from 'dart:core'.
+//   [...?l]; // Warning.
+//        ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:32:16: Warning: Operand of null-aware operation '...?' has type 'List<String>' which excludes null.
+//  - 'List' is from 'dart:core'.
+//   var a = {...?l}; // Warning.
+//                ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:33:16: Warning: Operand of null-aware operation '...?' has type 'List<String>' which excludes null.
+//  - 'List' is from 'dart:core'.
+//   <String>{...?l}; // Warning.
+//                ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:34:16: Warning: Operand of null-aware operation '...?' has type 'Map<String, int>' which excludes null.
+//  - 'Map' is from 'dart:core'.
+//   var b = {...?m}; // Warning.
+//                ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:35:21: Warning: Operand of null-aware operation '...?' has type 'Map<String, int>' which excludes null.
+//  - 'Map' is from 'dart:core'.
+//   <String, int>{...?m}; // Warning.
+//                     ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:36:3: Warning: Operand of null-aware operation '!' has type 'String' which excludes null.
+//   s!; // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:37:3: Warning: Operand of null-aware operation '?.' has type 'String' which excludes null.
+//   s?.substring(0, 0); // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:38:3: Warning: Operand of null-aware operation '?.' has type 'List<String>' which excludes null.
+//  - 'List' is from 'dart:core'.
+//   l?.length = 42; // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:39:3: Warning: Operand of null-aware operation '?.' has type 'List<String>' which excludes null.
+//  - 'List' is from 'dart:core'.
+//   l?.length += 42; // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:40:3: Warning: Operand of null-aware operation '?.' has type 'List<String>' which excludes null.
+//  - 'List' is from 'dart:core'.
+//   l?.length ??= 42; // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:41:3: Warning: Operand of null-aware operation '?.' has type 'String' which excludes null.
+//   s?.foo; // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:42:7: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   E(s)[42] ??= 42; // Warning.
+//       ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:43:4: Warning: Operand of null-aware operation '??=' has type 'String' which excludes null.
+//   l[42] ??= "foo"; // Warning.
+//    ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:44:5: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   l.length ??= 42; // Warning.
+//     ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:45:3: Warning: Operand of null-aware operation '?..' has type 'List<String>' which excludes null.
+//  - 'List' is from 'dart:core'.
+//   l?..length = 42; // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:46:3: Warning: Operand of null-aware operation '?..' has type 'List<String>' which excludes null.
+//  - 'List' is from 'dart:core'.
+//   l?..length ??= 42; // Warning.
+//   ^
+//
+// pkg/front_end/testcases/nnbd/strictly_non_nullable_warnings.dart:46:7: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   l?..length ??= 42; // Warning.
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  operator [](core::int index) → core::String
+    return "foo";
+  operator []=(core::int index, core::String value) → void {}
+}
+class B extends self::A {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+  method test() → void {
+    let final core::int #t1 = 42 in super.{self::A::[]}(#t1) == null ?{core::String} super.{self::A::[]=}(#t1, "bar") : null;
+  }
+}
+extension E on core::String {
+  get foo = self::E|get#foo;
+  operator []= = self::E|[]=;
+  operator [] = self::E|[];
+}
+static method E|get#foo(lowered final core::String #this) → core::int
+  return 42;
+static method E|[]=(lowered final core::String #this, core::int index, core::int value) → void {}
+static method E|[](lowered final core::String #this, core::int index) → core::int
+  return 42;
+static method warning(core::String s, core::List<core::String> l, core::Map<core::String, core::int> m) → dynamic {
+  let final core::String #t2 = s in #t2 == null ?{core::int?} null : #t2.{core::String::length}{core::int};
+  let final core::String #t3 = s in #t3 == null ?{core::String} null : block {
+    #t3.{core::String::length}{core::int};
+  } =>#t3;
+  let final core::String #t4 = s in #t4 == null ?{core::String} "foo" : #t4;
+  s == null ?{core::String} s = "foo" : null;
+  block {
+    final core::List<core::String> #t5 = <core::String>[];
+    final core::Iterable<core::String>? #t6 = l;
+    if(!(#t6 == null))
+      #t5.{core::List::addAll}{Invariant}(#t6{core::Iterable<core::String>}){(core::Iterable<core::String>) → void};
+  } =>#t5;
+  core::Set<core::String> a = block {
+    final core::Set<core::String> #t7 = col::LinkedHashSet::•<core::String>();
+    final core::Iterable<dynamic>? #t8 = l;
+    if(!(#t8 == null))
+      for (final dynamic #t9 in #t8{core::Iterable<dynamic>}) {
+        final core::String #t10 = #t9 as{TypeError,ForNonNullableByDefault} core::String;
+        #t7.{core::Set::add}{Invariant}(#t10){(core::String) → core::bool};
+      }
+  } =>#t7;
+  block {
+    final core::Set<core::String> #t11 = col::LinkedHashSet::•<core::String>();
+    final core::Iterable<core::String>? #t12 = l;
+    if(!(#t12 == null))
+      #t11.{core::Set::addAll}{Invariant}(#t12{core::Iterable<core::String>}){(core::Iterable<core::String>) → void};
+  } =>#t11;
+  core::Map<core::String, core::int> b = block {
+    final core::Map<core::String, core::int> #t13 = <core::String, core::int>{};
+    final core::Map<core::String, core::int>? #t14 = m;
+    if(!(#t14 == null))
+      for (final core::MapEntry<core::String, core::int> #t15 in #t14{core::Map<core::String, core::int>}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String, core::int>>})
+        #t13.{core::Map::[]=}{Invariant}(#t15.{core::MapEntry::key}{core::String}, #t15.{core::MapEntry::value}{core::int}){(core::String, core::int) → void};
+  } =>#t13;
+  block {
+    final core::Map<core::String, core::int> #t16 = <core::String, core::int>{};
+    final core::Map<core::String, core::int>? #t17 = m;
+    if(!(#t17 == null))
+      for (final core::MapEntry<core::String, core::int> #t18 in #t17{core::Map<core::String, core::int>}.{core::Map::entries}{core::Iterable<core::MapEntry<core::String, core::int>>})
+        #t16.{core::Map::[]=}{Invariant}(#t18.{core::MapEntry::key}{core::String}, #t18.{core::MapEntry::value}{core::int}){(core::String, core::int) → void};
+  } =>#t16;
+  s!;
+  let final core::String #t19 = s in #t19 == null ?{core::String?} null : #t19.{core::String::substring}(0, 0){(core::int, [core::int?]) → core::String};
+  let final core::List<core::String> #t20 = l in #t20 == null ?{core::int?} null : #t20.{core::List::length} = 42;
+  let final core::List<core::String> #t21 = l in #t21 == null ?{core::int?} null : #t21.{core::List::length} = #t21.{core::List::length}{core::int}.{core::num::+}(42){(core::num) → core::int};
+  let final core::List<core::String> #t22 = l in #t22 == null ?{core::int?} null : #t22.{core::List::length}{core::int} == null ?{core::int} #t22.{core::List::length} = 42 : null;
+  let final core::String #t23 = s in #t23 == null ?{core::int?} null : self::E|get#foo(#t23);
+  let final core::String #t24 = s in let final core::int #t25 = 42 in self::E|[](#t24, #t25) == null ?{core::int} self::E|[]=(#t24, #t25, 42) : null;
+  let final core::List<core::String> #t26 = l in let final core::int #t27 = 42 in #t26.{core::List::[]}(#t27){(core::int) → core::String} == null ?{core::String} #t26.{core::List::[]=}(#t27, "foo"){(core::int, core::String) → void} : null;
+  let final core::List<core::String> #t28 = l in #t28.{core::List::length}{core::int} == null ?{core::int} #t28.{core::List::length} = 42 : null;
+  let final core::List<core::String> #t29 = l in #t29 == null ?{core::List<core::String>} null : block {
+    #t29.{core::List::length} = 42;
+  } =>#t29;
+  let final core::List<core::String> #t30 = l in #t30 == null ?{core::List<core::String>} null : block {
+    let final core::List<core::String> #t31 = #t30 in #t31.{core::List::length}{core::int} == null ?{core::int} #t31.{core::List::length} = 42 : null;
+  } =>#t30;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/strong_lib_not_ok_from_dill/strong.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/strong_lib_not_ok_from_dill/strong.dart.weak.modular.expect
new file mode 100644
index 0000000..cb27086
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/strong_lib_not_ok_from_dill/strong.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "strong_lib.dart" as str;
+
+import "org-dartlang-testcase:///strong_lib.dart";
+
+static method main() → dynamic {
+  str::foo();
+}
diff --git a/pkg/front_end/testcases/nnbd/strong_lib_not_ok_from_source/strong.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/strong_lib_not_ok_from_source/strong.dart.weak.modular.expect
new file mode 100644
index 0000000..c9d352f
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/strong_lib_not_ok_from_source/strong.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "strong_lib.dart" as str;
+
+import "org-dartlang-testcase:///strong_lib.dart";
+
+static method main() → dynamic {
+  str::foo();
+}
+
+library;
+import self as str;
+import "dart:core" as core;
+
+static field core::int* x;
+static method foo() → void {
+  core::print("hello");
+}
diff --git a/pkg/front_end/testcases/nnbd/strong_ok_from_dill/strong.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/strong_ok_from_dill/strong.dart.weak.modular.expect
new file mode 100644
index 0000000..cb27086
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/strong_ok_from_dill/strong.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "strong_lib.dart" as str;
+
+import "org-dartlang-testcase:///strong_lib.dart";
+
+static method main() → dynamic {
+  str::foo();
+}
diff --git a/pkg/front_end/testcases/nnbd/strong_ok_from_source/strong.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/strong_ok_from_source/strong.dart.weak.modular.expect
new file mode 100644
index 0000000..385858b
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/strong_ok_from_source/strong.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "strong_lib.dart" as str;
+
+import "org-dartlang-testcase:///strong_lib.dart";
+
+static method main() → dynamic {
+  str::foo();
+}
+
+library /*isNonNullableByDefault*/;
+import self as str;
+import "dart:core" as core;
+
+static method foo() → void {
+  core::print("hello");
+}
diff --git a/pkg/front_end/testcases/nnbd/strong_package_not_ok_from_dill/strong.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/strong_package_not_ok_from_dill/strong.dart.weak.modular.expect
new file mode 100644
index 0000000..ba7e12e
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/strong_package_not_ok_from_dill/strong.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+
+import "package:opt_in_package/opt_in_lib.dart";
+import "package:opt_in_package/opt_out_lib.dart";
+import "package:opt_out_package/regular_lib1.dart";
+import "package:opt_out_package/regular_lib2.dart";
+
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/strong_package_not_ok_from_source/strong.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/strong_package_not_ok_from_source/strong.dart.weak.modular.expect
new file mode 100644
index 0000000..ba7e12e
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/strong_package_not_ok_from_source/strong.dart.weak.modular.expect
@@ -0,0 +1,9 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+
+import "package:opt_in_package/opt_in_lib.dart";
+import "package:opt_in_package/opt_out_lib.dart";
+import "package:opt_out_package/regular_lib1.dart";
+import "package:opt_out_package/regular_lib2.dart";
+
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/substitution_in_inference.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/substitution_in_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..b06ed29
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/substitution_in_inference.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object?, S extends core::Object> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T%, self::A::S>
+    : super core::Object::•()
+    ;
+  method hest<covariant-by-class X extends self::A::T%, Y extends core::List<self::A::hest::X%> = core::List<self::A::T%>, Z extends core::List<self::A::hest::X?> = core::List<self::A::T?>>() → dynamic
+    return null;
+  method fisk<covariant-by-class X extends self::A::S, Y extends core::List<self::A::fisk::X> = core::List<self::A::S>, Z extends core::List<self::A::fisk::X?> = core::List<self::A::S?>>() → dynamic
+    return null;
+  method mus<X extends core::Object?, Y extends core::List<self::A::mus::X%> = core::List<core::Object?>, Z extends core::List<self::A::mus::X?> = core::List<core::Object?>>() → dynamic
+    return null;
+}
+static method foo<T extends core::Object?, S extends core::List<self::foo::T%> = core::List<core::Object?>>(self::foo::T% t) → dynamic
+  return null;
+static method bar<T extends core::Object?, S extends core::List<self::bar::T?> = core::List<core::Object?>>(self::bar::T% t) → dynamic
+  return null;
+static method baz(core::int? x, core::int y) → dynamic {
+  self::foo<core::int?, core::List<core::int?>>(x);
+  self::bar<core::int, core::List<core::int?>>(y);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/super_bounded_hint.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/super_bounded_hint.dart.weak.modular.expect
new file mode 100644
index 0000000..5537cc3
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/super_bounded_hint.dart.weak.modular.expect
@@ -0,0 +1,618 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:15:7: Error: Generic type 'F' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'F' here.
+// foo2b<X extends F>() {}
+//       ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: Bound of this variable references variable 'X' from the same declaration.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:19:13: Error: Generic type 'F' can't be used without type arguments in a type variable bound.
+// Try providing type arguments to 'F' here.
+// class Foo3b<X extends F> {}
+//             ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: Bound of this variable references variable 'X' from the same declaration.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:11:31: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// foo1a(F<A<dynamic>, A<Never>> x) {}
+//                               ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:11:31: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+// foo1a(F<A<dynamic>, A<Never>> x) {}
+//                               ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:12:9: Error: Inferred type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// foo1b(F x) {}
+//         ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:12:9: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+// foo1b(F x) {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:14:7: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// foo2a<X extends F<A<dynamic>, A<Never>>>() {}
+//       ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:14:7: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+// foo2a<X extends F<A<dynamic>, A<Never>>>() {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:15:7: Error: Inferred type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// foo2b<X extends F>() {}
+//       ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:15:7: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+// foo2b<X extends F>() {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:17:13: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// class Foo3a<X extends F<A<dynamic>, A<Never>>> {}
+//             ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:17:13: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+// class Foo3a<X extends F<A<dynamic>, A<Never>>> {}
+//             ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:21:30: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F' in the return type.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// F<A<dynamic>, A<Never>> foo4a() => throw 42;
+//                              ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:21:30: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+// F<A<dynamic>, A<Never>> foo4a() => throw 42;
+//                              ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:22:8: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F' in the return type.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// F foo4b() => throw 42;
+//        ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:22:8: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+// F foo4b() => throw 42;
+//        ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:24:41: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// foo5a({required F<A<dynamic>, A<Never>> x}) {}
+//                                         ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:24:41: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+// foo5a({required F<A<dynamic>, A<Never>> x}) {}
+//                                         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:25:19: Error: Inferred type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// foo5b({required F x}) {}
+//                   ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:25:19: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+// foo5b({required F x}) {}
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:47:33: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// foo7a([F<A<dynamic>, A<Never>>? x]) {}
+//                                 ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:47:33: Context: If you want 'F<A<dynamic>, A<Never>>?' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>?' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+// foo7a([F<A<dynamic>, A<Never>>? x]) {}
+//                                 ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:48:11: Error: Inferred type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// foo7b([F? x]) {}
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:48:11: Context: If you want 'F<A<dynamic>, A<Never>>?' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>?' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+// foo7b([F? x]) {}
+//           ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:54:13: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'B'.
+// Try changing type arguments so that they conform to the bounds.
+// bar1(B<num> x) {}
+//             ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:56:6: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'B'.
+// Try changing type arguments so that they conform to the bounds.
+// bar2<X extends B<num>>() {}
+//      ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:58:12: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'B'.
+// Try changing type arguments so that they conform to the bounds.
+// class Bar3<X extends B<num>> {}
+//            ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:60:12: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'B' in the return type.
+// Try changing type arguments so that they conform to the bounds.
+// B<num> bar4() => throw 42;
+//            ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:62:23: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'B'.
+// Try changing type arguments so that they conform to the bounds.
+// bar5({required B<num> x}) {}
+//                       ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:76:15: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'B'.
+// Try changing type arguments so that they conform to the bounds.
+// bar7([B<num>? x]) {}
+//               ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:78:7: Error: Type argument 'dynamic' doesn't conform to the bound 'int' of the type variable 'X' on 'B' in the supertype 'B' of class 'Bar8'.
+// Try changing type arguments so that they conform to the bounds.
+// class Bar8 extends B<dynamic> {}
+//       ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:28:27: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   F<A<dynamic>, A<Never>> x;
+//                           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:28:27: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   F<A<dynamic>, A<Never>> x;
+//                           ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:29:32: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   for (F<A<dynamic>, A<Never>> x in []) {}
+//                                ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:29:32: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   for (F<A<dynamic>, A<Never>> x in []) {}
+//                                ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:29:37: Error: Inferred type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   for (F<A<dynamic>, A<Never>> x in []) {}
+//                                     ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:29:37: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   for (F<A<dynamic>, A<Never>> x in []) {}
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:30:35: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   fooFoo1(F<A<dynamic>, A<Never>> x) {}
+//                                   ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:30:35: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   fooFoo1(F<A<dynamic>, A<Never>> x) {}
+//                                   ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:31:11: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   fooFoo2<X extends F<A<dynamic>, A<Never>>>() {}
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:31:11: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   fooFoo2<X extends F<A<dynamic>, A<Never>>>() {}
+//           ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:32:34: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F' in the return type.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   F<A<dynamic>, A<Never>> fooFoo4() => throw 42;
+//                                  ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:32:34: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   F<A<dynamic>, A<Never>> fooFoo4() => throw 42;
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:33:45: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   fooFoo5({required F<A<dynamic>, A<Never>> x}) {}
+//                                             ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:33:45: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   fooFoo5({required F<A<dynamic>, A<Never>> x}) {}
+//                                             ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:34:37: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   fooFoo7([F<A<dynamic>, A<Never>>? x]) {}
+//                                     ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:34:37: Context: If you want 'F<A<dynamic>, A<Never>>?' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>?' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   fooFoo7([F<A<dynamic>, A<Never>>? x]) {}
+//                                     ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:38:5: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   F x;
+//     ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:38:5: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   F x;
+//     ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:39:10: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   for (F x in []) {}
+//          ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:39:10: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   for (F x in []) {}
+//          ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:39:15: Error: Inferred type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   for (F x in []) {}
+//               ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:39:15: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   for (F x in []) {}
+//               ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:40:13: Error: Inferred type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   fooFoo1(F x) {}
+//             ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:40:13: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   fooFoo1(F x) {}
+//             ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:41:11: Error: Inferred type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   fooFoo2<X extends F>() {}
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:41:11: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   fooFoo2<X extends F>() {}
+//           ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:42:12: Error: Type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F' in the return type.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   F fooFoo4() => throw 42;
+//            ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:42:12: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   F fooFoo4() => throw 42;
+//            ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:43:23: Error: Inferred type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   fooFoo5({required F x}) {}
+//                       ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:43:23: Context: If you want 'F<A<dynamic>, A<Never>>' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   fooFoo5({required F x}) {}
+//                       ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:44:15: Error: Inferred type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'F'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   fooFoo7([F? x]) {}
+//               ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef F<X extends A<X>, Y extends A<Y>> = X Function(Y);
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:44:15: Context: If you want 'F<A<dynamic>, A<Never>>?' to be a super-bounded type, note that the inverted type 'F<A<Never>, A<Object?>>?' must then satisfy its bounds, which it does not.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/super_bounded_hint.dart'.
+//  - 'Object' is from 'dart:core'.
+//   fooFoo7([F? x]) {}
+//               ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:65:10: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'B'.
+// Try changing type arguments so that they conform to the bounds.
+//   B<num> x;
+//          ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:66:15: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'B'.
+// Try changing type arguments so that they conform to the bounds.
+//   for (B<num> x in []) {}
+//               ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:72:7: Error: Type argument 'dynamic' doesn't conform to the bound 'int' of the type variable 'X' on 'B'.
+// Try changing type arguments so that they conform to the bounds.
+//   new B<dynamic>();
+//       ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:66:20: Error: Inferred type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'B'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   for (B<num> x in []) {}
+//                    ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:67:18: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'B'.
+// Try changing type arguments so that they conform to the bounds.
+//   barBar1(B<num> x) {}
+//                  ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:68:11: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'B'.
+// Try changing type arguments so that they conform to the bounds.
+//   barBar2<X extends B<num>>() {}
+//           ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:69:17: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'B' in the return type.
+// Try changing type arguments so that they conform to the bounds.
+//   B<num> barBar4() => throw 42;
+//                 ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:70:28: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'B'.
+// Try changing type arguments so that they conform to the bounds.
+//   barBar5({required B<num> x}) {}
+//                            ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:71:20: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'X' on 'B'.
+// Try changing type arguments so that they conform to the bounds.
+//   barBar7([B<num>? x]) {}
+//                    ^
+// pkg/front_end/testcases/nnbd/super_bounded_hint.dart:52:9: Context: This is the type variable whose bound isn't conformed to.
+// class B<X extends int> {}
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F<X extends self::A<X> = self::A<dynamic>, contravariant Y extends self::A<Y> = self::A<Never>> = (Y) → X;
+class A<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X%>
+    : super core::Object::•()
+    ;
+}
+class Foo3a<X extends (self::A<Never>) → self::A<dynamic>> extends core::Object {
+  synthetic constructor •() → self::Foo3a<self::Foo3a::X>
+    : super core::Object::•()
+    ;
+}
+class Foo3b<X extends (self::A<Never>) → self::A<dynamic> = dynamic> extends core::Object {
+  synthetic constructor •() → self::Foo3b<self::Foo3b::X>
+    : super core::Object::•()
+    ;
+}
+class B<X extends core::int> extends core::Object {
+  synthetic constructor •() → self::B<self::B::X>
+    : super core::Object::•()
+    ;
+}
+class Bar3<X extends self::B<core::num>> extends core::Object {
+  synthetic constructor •() → self::Bar3<self::Bar3::X>
+    : super core::Object::•()
+    ;
+}
+class Bar8 extends self::B<dynamic> {
+  synthetic constructor •() → self::Bar8
+    : super self::B::•()
+    ;
+}
+static method foo1a((self::A<Never>) → self::A<dynamic> x) → dynamic {}
+static method foo1b((self::A<Never>) → self::A<dynamic> x) → dynamic {}
+static method foo2a<X extends (self::A<Never>) → self::A<dynamic>>() → dynamic {}
+static method foo2b<X extends (self::A<Never>) → self::A<dynamic> = dynamic>() → dynamic {}
+static method foo4a() → (self::A<Never>) → self::A<dynamic>
+  return throw 42;
+static method foo4b() → (self::A<Never>) → self::A<dynamic>
+  return throw 42;
+static method foo5a({required (self::A<Never>) → self::A<dynamic> x = #C1}) → dynamic {}
+static method foo5b({required (self::A<Never>) → self::A<dynamic> x = #C1}) → dynamic {}
+static method foo6a() → dynamic {
+  (self::A<Never>) → self::A<dynamic> x;
+  for ((self::A<Never>) → self::A<dynamic> x in <(self::A<Never>) → self::A<dynamic>>[]) {
+  }
+  function fooFoo1((self::A<Never>) → self::A<dynamic> x) → Null {}
+  function fooFoo2<X extends (self::A<Never>) → self::A<dynamic>>() → Null {}
+  function fooFoo4() → (self::A<Never>) → self::A<dynamic>
+    return throw 42;
+  function fooFoo5({required (self::A<Never>) → self::A<dynamic> x = #C1}) → Null {}
+  function fooFoo7([(self::A<Never>) →? self::A<dynamic> x = #C1]) → Null {}
+}
+static method foo6b() → dynamic {
+  (self::A<Never>) → self::A<dynamic> x;
+  for ((self::A<Never>) → self::A<dynamic> x in <(self::A<Never>) → self::A<dynamic>>[]) {
+  }
+  function fooFoo1((self::A<Never>) → self::A<dynamic> x) → Null {}
+  function fooFoo2<X extends (self::A<Never>) → self::A<dynamic>>() → Null {}
+  function fooFoo4() → (self::A<Never>) → self::A<dynamic>
+    return throw 42;
+  function fooFoo5({required (self::A<Never>) → self::A<dynamic> x = #C1}) → Null {}
+  function fooFoo7([(self::A<Never>) →? self::A<dynamic> x = #C1]) → Null {}
+}
+static method foo7a([(self::A<Never>) →? self::A<dynamic> x = #C1]) → dynamic {}
+static method foo7b([(self::A<Never>) →? self::A<dynamic> x = #C1]) → dynamic {}
+static method bar1(self::B<core::num> x) → dynamic {}
+static method bar2<X extends self::B<core::num>>() → dynamic {}
+static method bar4() → self::B<core::num>
+  return throw 42;
+static method bar5({required self::B<core::num> x = #C1}) → dynamic {}
+static method bar6() → dynamic {
+  self::B<core::num> x;
+  for (self::B<core::num> x in <self::B<core::num>>[]) {
+  }
+  function barBar1(self::B<core::num> x) → Null {}
+  function barBar2<X extends self::B<core::num>>() → Null {}
+  function barBar4() → self::B<core::num>
+    return throw 42;
+  function barBar5({required self::B<core::num> x = #C1}) → Null {}
+  function barBar7([self::B<core::num>? x = #C1]) → Null {}
+  new self::B::•<dynamic>();
+  new self::A::•<self::B<dynamic>>();
+}
+static method bar7([self::B<core::num>? x = #C1]) → dynamic {}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd/switch_nullable_enum.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/switch_nullable_enum.dart.weak.modular.expect
new file mode 100644
index 0000000..da9cc12
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/switch_nullable_enum.dart.weak.modular.expect
@@ -0,0 +1,121 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/switch_nullable_enum.dart:7:5: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+// int method1(Enum? e) {
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Enum extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::Enum> values = #C7;
+  static const field self::Enum e1 = #C3;
+  static const field self::Enum e2 = #C6;
+  const constructor •(core::int index, core::String name) → self::Enum
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String
+    return "Enum.${this.{core::_Enum::_name}{core::String}}";
+}
+static method method1(self::Enum? e) → core::int {
+  switch(e) {
+    #L1:
+    case #C3:
+    case #C6:
+      {
+        return 0;
+      }
+  }
+  return invalid-expression "pkg/front_end/testcases/nnbd/switch_nullable_enum.dart:7:5: Error: A non-null value must be returned since the return type 'int' doesn't allow null.
+int method1(Enum? e) {
+    ^" in null;
+}
+static method method2(self::Enum? e) → core::int {
+  switch(e) {
+    #L2:
+    case #C3:
+    case #C6:
+      {
+        return 0;
+      }
+    #L3:
+    case #C8:
+      {
+        return 1;
+      }
+    #L4:
+    default:
+      throw new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable enum type.");
+  }
+}
+static method method3(self::Enum? e) → core::int {
+  switch(e) {
+    #L5:
+    case #C3:
+    case #C6:
+      {
+        return 0;
+      }
+    #L6:
+    default:
+      {
+        return 1;
+      }
+  }
+}
+static method method4(self::Enum? e) → core::int {
+  switch(e) {
+    #L7:
+    case #C3:
+    case #C6:
+      {
+        return 0;
+      }
+    #L8:
+    case #C8:
+    default:
+      {
+        return 1;
+      }
+  }
+}
+static method test() → dynamic {
+  self::method1(#C3);
+}
+static method main() → dynamic {
+  self::expect(0, self::method2(#C3));
+  self::expect(0, self::method2(#C6));
+  self::expect(1, self::method2(null));
+  self::expect(0, self::method3(#C3));
+  self::expect(0, self::method3(#C6));
+  self::expect(1, self::method3(null));
+  self::expect(0, self::method4(#C3));
+  self::expect(0, self::method4(#C6));
+  self::expect(1, self::method4(null));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual)) {
+    throw "Expected ${expected}, actual ${actual}.";
+  }
+}
+
+constants  {
+  #C1 = 0
+  #C2 = "e1"
+  #C3 = self::Enum {index:#C1, _name:#C2}
+  #C4 = 1
+  #C5 = "e2"
+  #C6 = self::Enum {index:#C4, _name:#C5}
+  #C7 = <self::Enum*>[#C3, #C6]
+  #C8 = null
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///switch_nullable_enum.dart:
+- Enum. (from org-dartlang-testcase:///switch_nullable_enum.dart:5:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:76:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd/switch_redesign_fall_over.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/switch_redesign_fall_over.dart.weak.modular.expect
new file mode 100644
index 0000000..e074f2a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/switch_redesign_fall_over.dart.weak.modular.expect
@@ -0,0 +1,58 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/switch_redesign_fall_over.dart:23:5: Error: Switch case may fall through to the next case.
+//     case -42: // Error.
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  method foo(core::int x, core::bool b) → dynamic {
+    switch(x) {
+      #L1:
+      case #C1:
+        {
+          let final Never #t1 = this.{self::A::neverReturn}(){() → Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+        }
+      #L2:
+      default:
+        {
+          self::bar();
+        }
+    }
+  }
+  abstract method neverReturn() → Never;
+}
+static method bar() → dynamic {}
+static method foo(core::int x, core::bool b) → dynamic {
+  switch(x) {
+    #L3:
+    case #C1:
+      {
+        let final Never #t2 = b ?{Never} throw "hest" : throw "fisk" in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+      }
+    #L4:
+    case #C2:
+      {
+        self::bar();
+      }
+    #L5:
+    default:
+      {
+        self::bar();
+      }
+  }
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 42
+  #C2 = -42
+}
diff --git a/pkg/front_end/testcases/nnbd/switch_redesign_types.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/switch_redesign_types.dart.weak.modular.expect
new file mode 100644
index 0000000..0d7d320
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/switch_redesign_types.dart.weak.modular.expect
@@ -0,0 +1,110 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/switch_redesign_types.dart:35:16: Error: Type 'A' of the case expression is not a subtype of type 'B' of this switch expression.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd/switch_redesign_types.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/switch_redesign_types.dart'.
+//     case const A(42): // Error: not a subtype of B.
+//                ^
+// pkg/front_end/testcases/nnbd/switch_redesign_types.dart:30:11: Context: The switch expression is here.
+//   switch (b) {
+//           ^
+//
+// pkg/front_end/testcases/nnbd/switch_redesign_types.dart:39:10: Error: Type 'dynamic' of the case expression is not a subtype of type 'B' of this switch expression.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd/switch_redesign_types.dart'.
+//     case x: // Error: D has custom operator ==.
+//          ^
+// pkg/front_end/testcases/nnbd/switch_redesign_types.dart:30:11: Context: The switch expression is here.
+//   switch (b) {
+//           ^
+//
+// pkg/front_end/testcases/nnbd/switch_redesign_types.dart:37:16: Error: Case expression 'D {}' does not have a primitive operator '=='.
+//  - 'D' is from 'pkg/front_end/testcases/nnbd/switch_redesign_types.dart'.
+//     case const D(42): // Error: D has custom operator ==.
+//                ^
+//
+// pkg/front_end/testcases/nnbd/switch_redesign_types.dart:39:10: Error: Case expression 'D {}' does not have a primitive operator '=='.
+//  - 'D' is from 'pkg/front_end/testcases/nnbd/switch_redesign_types.dart'.
+//     case x: // Error: D has custom operator ==.
+//          ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object /*hasConstConstructor*/  {
+  final field core::int foo;
+  const constructor •(core::int foo) → self::A
+    : self::A::foo = foo, super core::Object::•()
+    ;
+}
+class B extends self::A /*hasConstConstructor*/  {
+  const constructor •(core::int foo) → self::B
+    : super self::A::•(foo)
+    ;
+}
+class C extends self::B /*hasConstConstructor*/  {
+  const constructor •(core::int foo) → self::C
+    : super self::B::•(foo)
+    ;
+}
+class D extends self::B /*hasConstConstructor*/  {
+  const constructor •(core::int foo) → self::D
+    : super self::B::•(foo)
+    ;
+  operator ==(dynamic other) → core::bool
+    return core::identical(this, other);
+}
+static method bar(self::B b) → dynamic {
+  #L1:
+  switch(b) {
+    #L2:
+    case #C2:
+      {
+        break #L1;
+      }
+    #L3:
+    case #C3:
+      {
+        break #L1;
+      }
+    #L4:
+    case #C4:
+      {
+        break #L1;
+      }
+    #L5:
+    case #C5:
+      {
+        break #L1;
+      }
+    #L6:
+    case #C7:
+      {
+        break #L1;
+      }
+    #L7:
+    default:
+      {}
+  }
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 42
+  #C2 = self::B {foo:#C1}
+  #C3 = self::C {foo:#C1}
+  #C4 = self::A {foo:#C1}
+  #C5 = self::D {foo:#C1}
+  #C6 = 123
+  #C7 = self::D {foo:#C6}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///switch_redesign_types.dart:
+- D. (from org-dartlang-testcase:///switch_redesign_types.dart:23:9)
+- B. (from org-dartlang-testcase:///switch_redesign_types.dart:15:9)
+- A. (from org-dartlang-testcase:///switch_redesign_types.dart:11:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- C. (from org-dartlang-testcase:///switch_redesign_types.dart:19:9)
diff --git a/pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart.weak.modular.expect
new file mode 100644
index 0000000..ad453ca
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart.weak.modular.expect
@@ -0,0 +1,93 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:14:24: Error: Can't tear off method 'call' from a potentially null value.
+//   functionContext(null as C?); // Error.
+//                        ^
+//
+// pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:15:32: Error: Can't tear off method 'call' from a potentially null value.
+//   nullableFunctionContext(null as C?); // Error.
+//                                ^
+//
+// pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:16:19: Error: Can't tear off method 'call' from a potentially null value.
+//   functionContext(c); // Error.
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:17:27: Error: Can't tear off method 'call' from a potentially null value.
+//   nullableFunctionContext(c); // Error.
+//                           ^
+//
+// pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:18:19: Error: The argument type 'T' can't be assigned to the parameter type 'int Function()'.
+//   functionContext(t); // Error.
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:19:27: Error: The argument type 'T' can't be assigned to the parameter type 'int Function()?'.
+//   nullableFunctionContext(t); // Error.
+//                           ^
+//
+// pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:20:19: Error: The argument type 'T?' can't be assigned to the parameter type 'int Function()'.
+//   functionContext(nt); // Error.
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:21:27: Error: The argument type 'T?' can't be assigned to the parameter type 'int Function()?'.
+//   nullableFunctionContext(nt); // Error.
+//                           ^
+//
+// pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:27:19: Error: The argument type 'T' can't be assigned to the parameter type 'int Function()'.
+//   functionContext(t); // Shouldn't result in a compile-time error.
+//                   ^
+//
+// pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:28:27: Error: The argument type 'T' can't be assigned to the parameter type 'int Function()?'.
+//   nullableFunctionContext(t); // Shouldn't result in a compile-time error.
+//                           ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  method call() → core::int
+    return 0;
+}
+static method functionContext(() → core::int f) → dynamic {}
+static method nullableFunctionContext(() →? core::int f) → dynamic {}
+static method foo<T extends self::C?>(self::C? c, self::foo::T% t, self::foo::T? nt) → dynamic {
+  self::functionContext(invalid-expression "pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:14:24: Error: Can't tear off method 'call' from a potentially null value.
+  functionContext(null as C?); // Error.
+                       ^" in (null as{ForNonNullableByDefault} self::C?) as{TypeError} () → core::int);
+  self::nullableFunctionContext(invalid-expression "pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:15:32: Error: Can't tear off method 'call' from a potentially null value.
+  nullableFunctionContext(null as C?); // Error.
+                               ^" in (null as{ForNonNullableByDefault} self::C?) as{TypeError} () →? core::int);
+  self::functionContext(invalid-expression "pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:16:19: Error: Can't tear off method 'call' from a potentially null value.
+  functionContext(c); // Error.
+                  ^" in c as{TypeError} () → core::int);
+  self::nullableFunctionContext(invalid-expression "pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:17:27: Error: Can't tear off method 'call' from a potentially null value.
+  nullableFunctionContext(c); // Error.
+                          ^" in c as{TypeError} () →? core::int);
+  self::functionContext(invalid-expression "pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:18:19: Error: The argument type 'T' can't be assigned to the parameter type 'int Function()'.
+  functionContext(t); // Error.
+                  ^" in t as{TypeError,ForNonNullableByDefault} () → core::int);
+  self::nullableFunctionContext(invalid-expression "pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:19:27: Error: The argument type 'T' can't be assigned to the parameter type 'int Function()?'.
+  nullableFunctionContext(t); // Error.
+                          ^" in t as{TypeError,ForNonNullableByDefault} () →? core::int);
+  self::functionContext(invalid-expression "pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:20:19: Error: The argument type 'T?' can't be assigned to the parameter type 'int Function()'.
+  functionContext(nt); // Error.
+                  ^" in nt as{TypeError,ForNonNullableByDefault} () → core::int);
+  self::nullableFunctionContext(invalid-expression "pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:21:27: Error: The argument type 'T?' can't be assigned to the parameter type 'int Function()?'.
+  nullableFunctionContext(nt); // Error.
+                          ^" in nt as{TypeError,ForNonNullableByDefault} () →? core::int);
+}
+static method bar<T extends self::C>(self::C c, self::bar::T t) → dynamic {
+  self::functionContext(let final self::C #t1 = c in #t1 == null ?{() → core::int} null : #t1.{self::C::call}{() → core::int});
+  self::nullableFunctionContext(let final self::C #t2 = c in #t2 == null ?{() → core::int} null : #t2.{self::C::call}{() → core::int});
+  self::functionContext(invalid-expression "pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:27:19: Error: The argument type 'T' can't be assigned to the parameter type 'int Function()'.
+  functionContext(t); // Shouldn't result in a compile-time error.
+                  ^" in t as{TypeError,ForNonNullableByDefault} () → core::int);
+  self::nullableFunctionContext(invalid-expression "pkg/front_end/testcases/nnbd/tearoff_from_nullable_receiver.dart:28:27: Error: The argument type 'T' can't be assigned to the parameter type 'int Function()?'.
+  nullableFunctionContext(t); // Shouldn't result in a compile-time error.
+                          ^" in t as{TypeError,ForNonNullableByDefault} () →? core::int);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/type_constraint_solving_closures_in_upper_and_lower_bounds.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/type_constraint_solving_closures_in_upper_and_lower_bounds.dart.weak.modular.expect
new file mode 100644
index 0000000..b10539b
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/type_constraint_solving_closures_in_upper_and_lower_bounds.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd/type_constraint_solving_closures_in_upper_and_lower_bounds.dart:15:14: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+//   String s = x; // Should be an error, `T` should be int.
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C<X extends core::Object? = dynamic> extends core::Object {
+  constructor •((self::C::X%) → void x) → self::C<self::C::X%>
+    : super core::Object::•()
+    ;
+}
+static method check<T extends core::Object? = dynamic>(self::C<core::List<self::check::T%>> f) → self::check::T% {
+  return null as{ForNonNullableByDefault} self::check::T%;
+}
+static method test() → void {
+  core::int x = self::check<core::int>(new self::C::•<core::List<core::int>>((core::List<core::int> x) → void {}));
+  core::String s = invalid-expression "pkg/front_end/testcases/nnbd/type_constraint_solving_closures_in_upper_and_lower_bounds.dart:15:14: Error: A value of type 'int' can't be assigned to a variable of type 'String'.
+  String s = x; // Should be an error, `T` should be int.
+             ^" in x as{TypeError,ForNonNullableByDefault} core::String;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/type_parameter_types.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/type_parameter_types.dart.weak.modular.expect
new file mode 100644
index 0000000..220ce86
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/type_parameter_types.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class A<X extends core::Object, Y extends core::Object?> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X, self::A::Y%>
+    : super core::Object::•()
+    ;
+  method foo() → self::A::X
+    return let final Never #t1 = self::never() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  method bar() → self::A::X?
+    return null;
+  method baz() → self::A::Y%
+    return let final Never #t2 = self::never() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+}
+class B<X extends core::List<self::B::Y%> = core::List<core::Object?>, Y extends core::Object?> extends core::Object {
+  synthetic constructor •() → self::B<self::B::X, self::B::Y%>
+    : super core::Object::•()
+    ;
+  method foo(covariant-by-class self::B::X x, covariant-by-class self::B::Y% y) → dynamic {}
+}
+class C<X extends core::List<self::C::Y%>? = core::List<dynamic>?, Y extends core::List<self::C::X%>? = core::List<dynamic>?> extends core::Object {
+  synthetic constructor •() → self::C<self::C::X%, self::C::Y%>
+    : super core::Object::•()
+    ;
+  method foo(covariant-by-class self::C::X% x, covariant-by-class self::C::Y% y) → dynamic {}
+}
+class D<X extends self::D::Y% = dynamic, Y extends self::D::Z% = dynamic, Z extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::D<self::D::X%, self::D::Y%, self::D::Z%>
+    : super core::Object::•()
+    ;
+  method foo(covariant-by-class self::D::X% x, covariant-by-class self::D::Y% y, covariant-by-class self::D::Z% z) → dynamic {}
+}
+static method never() → Never
+  return throw "Never";
+static method main() → dynamic {
+  function fun1<X extends core::Object, Y extends core::Object?>() → X
+    return let final Never #t3 = self::never() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  function fun2<X extends core::Object, Y extends core::Object?>() → Y%
+    return let final Never #t4 = self::never() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  function fun3<X extends core::List<Y%> = core::List<core::Object?>, Y extends core::Object?>() → X
+    return let final Never #t5 = self::never() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  function fun4<X extends core::List<Y%> = core::List<core::Object?>, Y extends core::Object?>() → Y%
+    return let final Never #t6 = self::never() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  function fun5<X extends core::List<Y%>? = core::List<dynamic>?, Y extends core::List<X%>? = core::List<dynamic>?>() → X%
+    return let final Never #t7 = self::never() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  function fun6<X extends core::List<Y%>? = core::List<dynamic>?, Y extends core::List<X%>? = core::List<dynamic>?>() → Y%
+    return let final Never #t8 = self::never() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  function fun7<X extends Y% = dynamic, Y extends Z% = dynamic, Z extends core::Object? = dynamic>() → X%
+    return let final Never #t9 = self::never() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  function fun8<X extends Y% = dynamic, Y extends Z% = dynamic, Z extends core::Object? = dynamic>() → Y%
+    return let final Never #t10 = self::never() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  function fun9<X extends Y% = dynamic, Y extends Z% = dynamic, Z extends core::Object? = dynamic>() → Z%
+    return let final Never #t11 = self::never() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+}
diff --git a/pkg/front_end/testcases/nnbd/uninitialized_non_nullable_late_fields.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/uninitialized_non_nullable_late_fields.dart.weak.modular.expect
new file mode 100644
index 0000000..bdb8fdc
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/uninitialized_non_nullable_late_fields.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  late field core::int x;
+  constructor foo(core::int x) → self::A
+    : self::A::x = x, super core::Object::•()
+    ;
+  constructor bar() → self::A
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd/upper_bound_on_promoted_type.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd/upper_bound_on_promoted_type.dart.weak.modular.expect
new file mode 100644
index 0000000..8aa9644
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd/upper_bound_on_promoted_type.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Foo<T extends core::Object? = dynamic> extends core::Object {
+  field dynamic bar = null;
+  field dynamic baz = null;
+  synthetic constructor •() → self::Foo<self::Foo::T%>
+    : super core::Object::•()
+    ;
+  method qux() → dynamic {
+    final self::Foo::T? v = this.{self::Foo::bar}{dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} self::Foo::T?;
+    if(v is{ForNonNullableByDefault} core::num) {
+      this.{self::Foo::baz}{dynamic}{dynamic}.[]=("value", v{self::Foo::T? & core::num /* '?' & '!' = '!' */}.{core::num::isFinite}{core::bool} ?{core::Object} v{self::Foo::T? & core::num /* '?' & '!' = '!' */} : v{self::Foo::T? & core::num /* '?' & '!' = '!' */}.{core::num::toString}(){() → core::String});
+    }
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/bad_mixins.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/bad_mixins.dart.weak.modular.expect
new file mode 100644
index 0000000..7245adf
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/bad_mixins.dart.weak.modular.expect
@@ -0,0 +1,698 @@
+//
+// Problems in component:
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins.dart:15:7: Error: 'B with MixinB' can't implement both 'B<num>' and 'B<int>'
+//  - 'B' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class2c extends B<num> with MixinB<int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins.dart:19:7: Error: 'B with MixinB' can't implement both 'B<Object>' and 'B<dynamic>'
+//  - 'B' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'Object' is from 'dart:core'.
+// class Class2e extends B<Object> with MixinB<dynamic> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins.dart:23:7: Error: 'C with MixinC' can't implement both 'C<num, num>' and 'C<num, int>'
+//  - 'C' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class3b extends C<num, num> with MixinC<num, int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:23:7: Error: 'B with MixinB' can't implement both 'B<int?>' and 'B<int>'
+//  - 'B' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class2b extends B<int?> with MixinB<int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:25:7: Error: 'B with MixinB' can't implement both 'B<num>' and 'B<int>'
+//  - 'B' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class2c extends B<num> with MixinB<int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:29:7: Error: 'B with MixinB' can't implement both 'B<Object>' and 'B<dynamic>'
+//  - 'B' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'Object' is from 'dart:core'.
+// class Class2e extends B<Object> with MixinB<dynamic> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:35:7: Error: 'C with MixinC' can't implement both 'C<num, num>' and 'C<num, int>'
+//  - 'C' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class3b extends C<num, num> with MixinC<num, int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:37:7: Error: 'C with MixinC' can't implement both 'C<num?, int>' and 'C<num, int>'
+//  - 'C' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class3c extends C<num?, int> with MixinC<num, int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:49:7: Error: 'ClassBa with MixinB' can't implement both 'B<int?>' and 'B<int>'
+//  - 'B' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class4a extends ClassBa with MixinB<int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:53:7: Error: 'ClassBb with MixinB' can't implement both 'B<int>' and 'B<int?>'
+//  - 'B' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class4c extends ClassBb with MixinB<int?> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:57:7: Error: 'ClassCa with MixinC' can't implement both 'C<num?, int?>' and 'C<num?, int>'
+//  - 'C' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class5a extends ClassCa with MixinC<num?, int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:61:7: Error: 'ClassCb with MixinC' can't implement both 'C<num?, int>' and 'C<num?, int?>'
+//  - 'C' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class5c extends ClassCb with MixinC<num?, int?> {} // error
+//       ^
+//
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins.dart:9:7: Error: 'Object' doesn't implement 'A' so it can't be used with 'MixinA'.
+//  - 'Object' is from 'dart:core'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinA' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class1a extends Object with MixinA {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins.dart:13:7: Error: 'Object' doesn't implement 'B<int>' so it can't be used with 'MixinB<int>'.
+//  - 'Object' is from 'dart:core'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinB' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class2a extends Object with MixinB<int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins.dart:15:7: Error: 'B<num>' doesn't implement 'B<int>' so it can't be used with 'MixinB<int>'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinB' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class2c extends B<num> with MixinB<int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins.dart:21:7: Error: 'Object' doesn't implement 'C<num, int>' so it can't be used with 'MixinC<num, int>'.
+//  - 'Object' is from 'dart:core'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinC' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class3a extends Object with MixinC<num, int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins.dart:23:7: Error: 'C<num, num>' doesn't implement 'C<num, int>' so it can't be used with 'MixinC<num, int>'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinC' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class3b extends C<num, num> with MixinC<num, int> {} // error
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+import "bad_mixins_lib.dart" as bad;
+
+import "org-dartlang-testcase:///bad_mixins_lib.dart";
+
+abstract class _Class1a&Object&MixinA = core::Object with bad::MixinA /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Class1a&Object&MixinA*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class1a extends self::_Class1a&Object&MixinA {
+  synthetic constructor •() → self::Class1a*
+    : super self::_Class1a&Object&MixinA::•()
+    ;
+}
+abstract class _Class1b&A&MixinA = bad::A with bad::MixinA /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class1b&A&MixinA*
+    : super bad::A::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class1b extends self::_Class1b&A&MixinA {
+  synthetic constructor •() → self::Class1b*
+    : super self::_Class1b&A&MixinA::•()
+    ;
+}
+abstract class _Class2a&Object&MixinB = core::Object with bad::MixinB<core::int*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Class2a&Object&MixinB*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class2a extends self::_Class2a&Object&MixinB {
+  synthetic constructor •() → self::Class2a*
+    : super self::_Class2a&Object&MixinB::•()
+    ;
+}
+abstract class _Class2c&B&MixinB = bad::B<core::num*> with bad::MixinB<core::int*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class2c&B&MixinB*
+    : super bad::B::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class2c extends self::_Class2c&B&MixinB {
+  synthetic constructor •() → self::Class2c*
+    : super self::_Class2c&B&MixinB::•()
+    ;
+}
+abstract class _Class2d&B&MixinB = bad::B<core::int*> with bad::MixinB<core::int*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class2d&B&MixinB*
+    : super bad::B::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class2d extends self::_Class2d&B&MixinB {
+  synthetic constructor •() → self::Class2d*
+    : super self::_Class2d&B&MixinB::•()
+    ;
+}
+abstract class _Class2e&B&MixinB = bad::B<core::Object*> with bad::MixinB<dynamic> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class2e&B&MixinB*
+    : super bad::B::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class2e extends self::_Class2e&B&MixinB {
+  synthetic constructor •() → self::Class2e*
+    : super self::_Class2e&B&MixinB::•()
+    ;
+}
+abstract class _Class3a&Object&MixinC = core::Object with bad::MixinC<core::num*, core::int*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Class3a&Object&MixinC*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class3a extends self::_Class3a&Object&MixinC {
+  synthetic constructor •() → self::Class3a*
+    : super self::_Class3a&Object&MixinC::•()
+    ;
+}
+abstract class _Class3b&C&MixinC = bad::C<core::num*, core::num*> with bad::MixinC<core::num*, core::int*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class3b&C&MixinC*
+    : super bad::C::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class3b extends self::_Class3b&C&MixinC {
+  synthetic constructor •() → self::Class3b*
+    : super self::_Class3b&C&MixinC::•()
+    ;
+}
+abstract class _Class3d&C&MixinC = bad::C<core::num*, core::int*> with bad::MixinC<core::num*, core::int*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class3d&C&MixinC*
+    : super bad::C::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class3d extends self::_Class3d&C&MixinC {
+  synthetic constructor •() → self::Class3d*
+    : super self::_Class3d&C&MixinC::•()
+    ;
+}
+abstract class _Class4a&ClassBa&MixinB = bad::ClassBa with bad::MixinB<core::int*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class4a&ClassBa&MixinB*
+    : super bad::ClassBa::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class4a extends self::_Class4a&ClassBa&MixinB {
+  synthetic constructor •() → self::Class4a*
+    : super self::_Class4a&ClassBa&MixinB::•()
+    ;
+}
+abstract class _Class4b&ClassBb&MixinB = bad::ClassBb with bad::MixinB<core::int*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class4b&ClassBb&MixinB*
+    : super bad::ClassBb::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class4b extends self::_Class4b&ClassBb&MixinB {
+  synthetic constructor •() → self::Class4b*
+    : super self::_Class4b&ClassBb&MixinB::•()
+    ;
+}
+abstract class _Class5a&ClassCa&MixinC = bad::ClassCa with bad::MixinC<core::num*, core::int*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class5a&ClassCa&MixinC*
+    : super bad::ClassCa::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class5a extends self::_Class5a&ClassCa&MixinC {
+  synthetic constructor •() → self::Class5a*
+    : super self::_Class5a&ClassCa&MixinC::•()
+    ;
+}
+abstract class _Class5b&ClassCb&MixinC = bad::ClassCb with bad::MixinC<core::num*, core::int*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class5b&ClassCb&MixinC*
+    : super bad::ClassCb::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class5b extends self::_Class5b&ClassCb&MixinC {
+  synthetic constructor •() → self::Class5b*
+    : super self::_Class5b&ClassCb&MixinC::•()
+    ;
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:17:7: Error: 'Object' doesn't implement 'A' so it can't be used with 'MixinA'.
+//  - 'Object' is from 'dart:core'.
+//  - 'A' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinA' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class1a extends Object with MixinA {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:21:7: Error: 'Object' doesn't implement 'B<int>' so it can't be used with 'MixinB<int>'.
+//  - 'Object' is from 'dart:core'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinB' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class2a extends Object with MixinB<int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:23:7: Error: 'B<int?>' doesn't implement 'B<int>' so it can't be used with 'MixinB<int>'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinB' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class2b extends B<int?> with MixinB<int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:25:7: Error: 'B<num>' doesn't implement 'B<int>' so it can't be used with 'MixinB<int>'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinB' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class2c extends B<num> with MixinB<int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:29:7: Error: 'B<Object>' doesn't implement 'B<dynamic>' so it can't be used with 'MixinB<dynamic>'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'Object' is from 'dart:core'.
+//  - 'MixinB' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class2e extends B<Object> with MixinB<dynamic> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:33:7: Error: 'Object' doesn't implement 'C<num, int>' so it can't be used with 'MixinC<num, int>'.
+//  - 'Object' is from 'dart:core'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinC' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class3a extends Object with MixinC<num, int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:35:7: Error: 'C<num, num>' doesn't implement 'C<num, int>' so it can't be used with 'MixinC<num, int>'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinC' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class3b extends C<num, num> with MixinC<num, int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:37:7: Error: 'C<num?, int>' doesn't implement 'C<num, int>' so it can't be used with 'MixinC<num, int>'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinC' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class3c extends C<num?, int> with MixinC<num, int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:49:7: Error: 'ClassBa' doesn't implement 'B<int>' so it can't be used with 'MixinB<int>'.
+//  - 'ClassBa' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinB' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class4a extends ClassBa with MixinB<int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:53:7: Error: 'ClassBb' doesn't implement 'B<int?>' so it can't be used with 'MixinB<int?>'.
+//  - 'ClassBb' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinB' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class4c extends ClassBb with MixinB<int?> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:57:7: Error: 'ClassCa' doesn't implement 'C<num?, int>' so it can't be used with 'MixinC<num?, int>'.
+//  - 'ClassCa' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinC' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class5a extends ClassCa with MixinC<num?, int> {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart:61:7: Error: 'ClassCb' doesn't implement 'C<num?, int?>' so it can't be used with 'MixinC<num?, int?>'.
+//  - 'ClassCb' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+//  - 'MixinC' is from 'pkg/front_end/testcases/nnbd_mixed/bad_mixins_lib.dart'.
+// class Class5c extends ClassCb with MixinC<num?, int?> {} // error
+//       ^
+//
+import self as bad;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → bad::A
+    : super core::Object::•()
+    ;
+}
+class B<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → bad::B<bad::B::T%>
+    : super core::Object::•()
+    ;
+}
+class C<T extends core::Object? = dynamic, S extends bad::C::T% = dynamic> extends core::Object {
+  synthetic constructor •() → bad::C<bad::C::T%, bad::C::S%>
+    : super core::Object::•()
+    ;
+}
+abstract class MixinA extends bad::A /*isMixinDeclaration*/  {
+}
+abstract class MixinB<T extends core::Object? = dynamic> extends bad::B<bad::MixinB::T%> /*isMixinDeclaration*/  {
+}
+abstract class MixinC<T extends core::Object? = dynamic, S extends bad::MixinC::T% = dynamic> extends bad::C<bad::MixinC::T%, bad::MixinC::S%> /*isMixinDeclaration*/  {
+}
+abstract class _Class1a&Object&MixinA = core::Object with bad::MixinA /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → bad::_Class1a&Object&MixinA
+    : super core::Object::•()
+    ;
+}
+class Class1a extends bad::_Class1a&Object&MixinA {
+  synthetic constructor •() → bad::Class1a
+    : super bad::_Class1a&Object&MixinA::•()
+    ;
+}
+abstract class _Class1b&A&MixinA = bad::A with bad::MixinA /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class1b&A&MixinA
+    : super bad::A::•()
+    ;
+}
+class Class1b extends bad::_Class1b&A&MixinA {
+  synthetic constructor •() → bad::Class1b
+    : super bad::_Class1b&A&MixinA::•()
+    ;
+}
+abstract class _Class2a&Object&MixinB = core::Object with bad::MixinB<core::int> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → bad::_Class2a&Object&MixinB
+    : super core::Object::•()
+    ;
+}
+class Class2a extends bad::_Class2a&Object&MixinB {
+  synthetic constructor •() → bad::Class2a
+    : super bad::_Class2a&Object&MixinB::•()
+    ;
+}
+abstract class _Class2b&B&MixinB = bad::B<core::int?> with bad::MixinB<core::int> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class2b&B&MixinB
+    : super bad::B::•()
+    ;
+}
+class Class2b extends bad::_Class2b&B&MixinB {
+  synthetic constructor •() → bad::Class2b
+    : super bad::_Class2b&B&MixinB::•()
+    ;
+}
+abstract class _Class2c&B&MixinB = bad::B<core::num> with bad::MixinB<core::int> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class2c&B&MixinB
+    : super bad::B::•()
+    ;
+}
+class Class2c extends bad::_Class2c&B&MixinB {
+  synthetic constructor •() → bad::Class2c
+    : super bad::_Class2c&B&MixinB::•()
+    ;
+}
+abstract class _Class2d&B&MixinB = bad::B<core::int> with bad::MixinB<core::int> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class2d&B&MixinB
+    : super bad::B::•()
+    ;
+}
+class Class2d extends bad::_Class2d&B&MixinB {
+  synthetic constructor •() → bad::Class2d
+    : super bad::_Class2d&B&MixinB::•()
+    ;
+}
+abstract class _Class2e&B&MixinB = bad::B<core::Object> with bad::MixinB<dynamic> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class2e&B&MixinB
+    : super bad::B::•()
+    ;
+}
+class Class2e extends bad::_Class2e&B&MixinB {
+  synthetic constructor •() → bad::Class2e
+    : super bad::_Class2e&B&MixinB::•()
+    ;
+}
+abstract class _Class2f&B&MixinB = bad::B<core::Object?> with bad::MixinB<dynamic> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class2f&B&MixinB
+    : super bad::B::•()
+    ;
+}
+class Class2f extends bad::_Class2f&B&MixinB {
+  synthetic constructor •() → bad::Class2f
+    : super bad::_Class2f&B&MixinB::•()
+    ;
+}
+abstract class _Class3a&Object&MixinC = core::Object with bad::MixinC<core::num, core::int> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → bad::_Class3a&Object&MixinC
+    : super core::Object::•()
+    ;
+}
+class Class3a extends bad::_Class3a&Object&MixinC {
+  synthetic constructor •() → bad::Class3a
+    : super bad::_Class3a&Object&MixinC::•()
+    ;
+}
+abstract class _Class3b&C&MixinC = bad::C<core::num, core::num> with bad::MixinC<core::num, core::int> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class3b&C&MixinC
+    : super bad::C::•()
+    ;
+}
+class Class3b extends bad::_Class3b&C&MixinC {
+  synthetic constructor •() → bad::Class3b
+    : super bad::_Class3b&C&MixinC::•()
+    ;
+}
+abstract class _Class3c&C&MixinC = bad::C<core::num?, core::int> with bad::MixinC<core::num, core::int> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class3c&C&MixinC
+    : super bad::C::•()
+    ;
+}
+class Class3c extends bad::_Class3c&C&MixinC {
+  synthetic constructor •() → bad::Class3c
+    : super bad::_Class3c&C&MixinC::•()
+    ;
+}
+abstract class _Class3d&C&MixinC = bad::C<core::num, core::int> with bad::MixinC<core::num, core::int> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class3d&C&MixinC
+    : super bad::C::•()
+    ;
+}
+class Class3d extends bad::_Class3d&C&MixinC {
+  synthetic constructor •() → bad::Class3d
+    : super bad::_Class3d&C&MixinC::•()
+    ;
+}
+class ClassBa extends bad::B<core::int?> {
+  synthetic constructor •() → bad::ClassBa
+    : super bad::B::•()
+    ;
+}
+class ClassBb extends bad::B<core::int> {
+  synthetic constructor •() → bad::ClassBb
+    : super bad::B::•()
+    ;
+}
+class ClassCa extends bad::C<core::num?, core::int?> {
+  synthetic constructor •() → bad::ClassCa
+    : super bad::C::•()
+    ;
+}
+class ClassCb extends bad::C<core::num?, core::int> {
+  synthetic constructor •() → bad::ClassCb
+    : super bad::C::•()
+    ;
+}
+abstract class _Class4a&ClassBa&MixinB = bad::ClassBa with bad::MixinB<core::int> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class4a&ClassBa&MixinB
+    : super bad::ClassBa::•()
+    ;
+}
+class Class4a extends bad::_Class4a&ClassBa&MixinB {
+  synthetic constructor •() → bad::Class4a
+    : super bad::_Class4a&ClassBa&MixinB::•()
+    ;
+}
+abstract class _Class4b&ClassBa&MixinB = bad::ClassBa with bad::MixinB<core::int?> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class4b&ClassBa&MixinB
+    : super bad::ClassBa::•()
+    ;
+}
+class Class4b extends bad::_Class4b&ClassBa&MixinB {
+  synthetic constructor •() → bad::Class4b
+    : super bad::_Class4b&ClassBa&MixinB::•()
+    ;
+}
+abstract class _Class4c&ClassBb&MixinB = bad::ClassBb with bad::MixinB<core::int?> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class4c&ClassBb&MixinB
+    : super bad::ClassBb::•()
+    ;
+}
+class Class4c extends bad::_Class4c&ClassBb&MixinB {
+  synthetic constructor •() → bad::Class4c
+    : super bad::_Class4c&ClassBb&MixinB::•()
+    ;
+}
+abstract class _Class4d&ClassBb&MixinB = bad::ClassBb with bad::MixinB<core::int> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class4d&ClassBb&MixinB
+    : super bad::ClassBb::•()
+    ;
+}
+class Class4d extends bad::_Class4d&ClassBb&MixinB {
+  synthetic constructor •() → bad::Class4d
+    : super bad::_Class4d&ClassBb&MixinB::•()
+    ;
+}
+abstract class _Class5a&ClassCa&MixinC = bad::ClassCa with bad::MixinC<core::num?, core::int> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class5a&ClassCa&MixinC
+    : super bad::ClassCa::•()
+    ;
+}
+class Class5a extends bad::_Class5a&ClassCa&MixinC {
+  synthetic constructor •() → bad::Class5a
+    : super bad::_Class5a&ClassCa&MixinC::•()
+    ;
+}
+abstract class _Class5b&ClassCa&MixinC = bad::ClassCa with bad::MixinC<core::num?, core::int?> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class5b&ClassCa&MixinC
+    : super bad::ClassCa::•()
+    ;
+}
+class Class5b extends bad::_Class5b&ClassCa&MixinC {
+  synthetic constructor •() → bad::Class5b
+    : super bad::_Class5b&ClassCa&MixinC::•()
+    ;
+}
+abstract class _Class5c&ClassCb&MixinC = bad::ClassCb with bad::MixinC<core::num?, core::int?> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class5c&ClassCb&MixinC
+    : super bad::ClassCb::•()
+    ;
+}
+class Class5c extends bad::_Class5c&ClassCb&MixinC {
+  synthetic constructor •() → bad::Class5c
+    : super bad::_Class5c&ClassCb&MixinC::•()
+    ;
+}
+abstract class _Class5d&ClassCb&MixinC = bad::ClassCb with bad::MixinC<core::num?, core::int> /*isAnonymousMixin*/  {
+  synthetic constructor •() → bad::_Class5d&ClassCb&MixinC
+    : super bad::ClassCb::•()
+    ;
+}
+class Class5d extends bad::_Class5d&ClassCb&MixinC {
+  synthetic constructor •() → bad::Class5d
+    : super bad::_Class5d&ClassCb&MixinC::•()
+    ;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/bounds_from_opt_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/bounds_from_opt_in.dart.weak.modular.expect
new file mode 100644
index 0000000..b07ab07
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/bounds_from_opt_in.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library;
+import self as self;
+import "bounds_from_opt_in_lib.dart" as bou;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///bounds_from_opt_in_lib.dart";
+
+class LegacyClass<T extends Null> extends bou::Class<self::LegacyClass::T*> {
+  synthetic constructor •() → self::LegacyClass<self::LegacyClass::T*>*
+    : super bou::Class::•()
+    ;
+  method method<T extends Null>() → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  bou::Class<Null>* c = new bou::Class::•<Null>();
+  c.{bou::Class::method}<Null>(){() →* dynamic};
+  bou::method<Null>();
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as bou;
+import "dart:core" as core;
+
+class Class<T extends Never> extends core::Object {
+  synthetic constructor •() → bou::Class<bou::Class::T>
+    : super core::Object::•()
+    ;
+  method method<T extends Never>() → dynamic {}
+}
+static method method<T extends Never>() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/call_opt_in_through_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/call_opt_in_through_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..524b85c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/call_opt_in_through_opt_out.dart.weak.modular.expect
@@ -0,0 +1,51 @@
+library;
+import self as self;
+import "call_opt_in_through_opt_out_lib.dart" as cal;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///call_opt_in_through_opt_out_lib.dart";
+
+static method test() → dynamic {
+  cal::applyTakesNever(#C1);
+  cal::applyTakesNever(#C2);
+  cal::applyTakesNull(#C1);
+  cal::applyTakesNull(#C2);
+  cal::applyTakesNeverNamed(f: #C1);
+  cal::applyTakesNeverNamed(f: #C2);
+  cal::applyTakesNullNamed(f: #C1);
+  cal::applyTakesNullNamed(f: #C2);
+  cal::applyTakesNonNullable(#C3);
+  cal::applyTakesNonNullable(#C4);
+  cal::applyTakesNullable(#C3);
+  cal::applyTakesNullable(#C4);
+  cal::applyTakesNonNullableNamed(f: #C3);
+  cal::applyTakesNonNullableNamed(f: #C4);
+  cal::applyTakesNullableNamed(f: #C3);
+  cal::applyTakesNullableNamed(f: #C4);
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as cal;
+import "dart:core" as core;
+
+static method takesNull(Null n) → void {}
+static method takesNever(Never n) → void {}
+static method applyTakesNull((Null) → void f) → dynamic {}
+static method applyTakesNever((Never) → void f) → dynamic {}
+static method applyTakesNullNamed({required (Null) → void f = #C5}) → dynamic {}
+static method applyTakesNeverNamed({required (Never) → void f = #C5}) → dynamic {}
+static method takesNullable(core::int? i) → void {}
+static method takesNonNullable(core::int i) → void {}
+static method applyTakesNullable((core::int?) → void f) → dynamic {}
+static method applyTakesNonNullable((core::int) → void f) → dynamic {}
+static method applyTakesNullableNamed({required (core::int?) → void f = #C5}) → dynamic {}
+static method applyTakesNonNullableNamed({required (core::int) → void f = #C5}) → dynamic {}
+
+constants  {
+  #C1 = static-tearoff cal::takesNever
+  #C2 = static-tearoff cal::takesNull
+  #C3 = static-tearoff cal::takesNonNullable
+  #C4 = static-tearoff cal::takesNullable
+  #C5 = null
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/const_canonical_type.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/const_canonical_type.dart.weak.modular.expect
new file mode 100644
index 0000000..50d1579
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/const_canonical_type.dart.weak.modular.expect
@@ -0,0 +1,119 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "const_canonical_type_lib.dart" as con;
+import "dart:core" as core;
+
+import "dart:async";
+import "org-dartlang-testcase:///const_canonical_type_lib.dart" as oo;
+
+typedef F1 = () → con::A<FutureOr<dynamic>>;
+typedef F2 = () → con::A<dynamic>;
+typedef F3 = () → con::A<FutureOr<FutureOr<dynamic>?>>;
+typedef F4 = () → con::A<dynamic>;
+class Check extends core::Object /*hasConstConstructor*/  {
+  final field dynamic _ignored;
+  const constructor •(dynamic x, dynamic y) → self::Check
+    : assert(core::identical(x, y)), self::Check::_ignored = core::identical(x, y) ?{core::int} 42 : 1.{core::num::~/}(0){(core::num) → core::int}, super core::Object::•()
+    ;
+}
+static method expectEqual(dynamic x, dynamic y) → void {
+  if(!(x =={core::Object::==}{(core::Object) → core::bool} y)) {
+    throw "Arguments were supposed to be identical.";
+  }
+}
+static method test1() → dynamic {
+  core::Type v = #C1;
+  self::expectEqual(#C1, v);
+  self::expectEqual(v, #C1);
+  self::expectEqual(#C1, con::v);
+  self::expectEqual(con::v, #C1);
+  self::expectEqual(#C1, #C1);
+  core::Type vf1 = #C2;
+  core::Type vf2 = #C2;
+  core::Type vf3 = #C2;
+  core::Type vf4 = #C2;
+  core::Type oovf1 = #C2;
+  core::Type oovf2 = #C2;
+  core::Type oovf3 = #C2;
+  core::Type oovf4 = #C2;
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, vf1);
+  self::expectEqual(vf1, vf2);
+  self::expectEqual(vf2, vf3);
+  self::expectEqual(vf3, vf4);
+  self::expectEqual(vf4, oovf1);
+  self::expectEqual(oovf1, oovf2);
+  self::expectEqual(oovf2, oovf3);
+  self::expectEqual(oovf3, oovf4);
+  self::expectEqual(oovf4, #C2);
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, #C2);
+  self::expectEqual(#C2, #C2);
+  return #C5;
+}
+static method main() → dynamic {
+  self::test1();
+}
+
+library;
+import self as con;
+import "dart:core" as core;
+
+import "dart:async";
+
+typedef F1 = () →* con::A<FutureOr<dynamic>*>*;
+typedef F2 = () →* con::A<dynamic>*;
+typedef F3 = () →* con::A<FutureOr<FutureOr<dynamic>*>*>*;
+typedef F4 = () →* con::A<dynamic>*;
+class A<X extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → con::A<con::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field core::Type* c = #C1;
+static field core::Type* v = #C1;
+static const field con::A<core::List<() →* con::A<FutureOr<dynamic>*>*>*>* a1 = #C6;
+static const field con::A<core::List<() →* con::A<dynamic>*>*>* a2 = #C6;
+static const field con::A<core::List<() →* con::A<FutureOr<FutureOr<dynamic>*>*>*>*>* a3 = #C6;
+static const field con::A<core::List<() →* con::A<dynamic>*>*>* a4 = #C6;
+
+constants  {
+  #C1 = TypeLiteralConstant(con::A<dynamic>*)
+  #C2 = TypeLiteralConstant(() →* con::A<dynamic>*)
+  #C3 = 42
+  #C4 = self::Check {_ignored:#C3}
+  #C5 = <dynamic>[#C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4]
+  #C6 = con::A<core::List<() →* con::A<dynamic>*>*> {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///const_canonical_type.dart:
+- A. (from org-dartlang-testcase:///const_canonical_type_lib.dart:10:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Check. (from org-dartlang-testcase:///const_canonical_type.dart:11:9)
+
+org-dartlang-testcase:///const_canonical_type_lib.dart:
+- A. (from org-dartlang-testcase:///const_canonical_type_lib.dart:10:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd_mixed/const_is.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/const_is.dart.weak.modular.expect
new file mode 100644
index 0000000..001ca03
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/const_is.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///const_is_lib.dart";
+
+static method main() → dynamic {
+  self::expect(true, #C1 is{ForNonNullableByDefault} <T extends core::Object?>() → void);
+  self::expect(true, #C2);
+  self::expect(true, #C3 is{ForNonNullableByDefault} <T extends Never = dynamic>() → void);
+  self::expect(true, #C2);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+library /*isNonNullableByDefault*/;
+import self as self2;
+import "dart:core" as core;
+
+typedef fnTypeWithNullableObjectBound = <T extends core::Object?>() → void;
+typedef fnTypeWithNeverBound = <T extends Never = dynamic>() → void;
+static method fnWithNonNullObjectBound<T extends core::Object>() → void
+  return null;
+static method fnWithNullBound<T extends Null>() → void
+  return null;
+
+constants  {
+  #C1 = static-tearoff self2::fnWithNonNullObjectBound
+  #C2 = true
+  #C3 = static-tearoff self2::fnWithNullBound
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/constant_null_is.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/constant_null_is.dart.weak.modular.expect
new file mode 100644
index 0000000..69b11ec
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/constant_null_is.dart.weak.modular.expect
@@ -0,0 +1,144 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "constant_null_is_lib.dart" as con;
+
+import "dart:async";
+import "org-dartlang-testcase:///constant_null_is_lib.dart";
+
+class Class<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field core::bool field;
+  const constructor constructor1(dynamic value) → self::Class<self::Class::T%>
+    : self::Class::field = value is{ForNonNullableByDefault} self::Class::T%, super core::Object::•()
+    ;
+  const constructor constructor2(dynamic value) → self::Class<self::Class::T%>
+    : self::Class::field = value is{ForNonNullableByDefault} self::Class::T?, super core::Object::•()
+    ;
+  const constructor constructor3(dynamic value) → self::Class<self::Class::T%>
+    : self::Class::field = value is{ForNonNullableByDefault} self::Class<self::Class::T%>, super core::Object::•()
+    ;
+  const constructor constructor4(dynamic value) → self::Class<self::Class::T%>
+    : self::Class::field = value is{ForNonNullableByDefault} self::Class<self::Class::T%>?, super core::Object::•()
+    ;
+}
+static final field core::bool isWeakMode = #C1 is{ForNonNullableByDefault} core::List<core::Object>;
+static const field core::bool c0 = #C2;
+static const field core::bool c1 = #C3;
+static const field core::bool c2 = #C2;
+static const field core::bool c3 = #C2;
+static const field core::bool c4 = #C3;
+static const field core::bool c5 = #C2;
+static const field core::bool c6 = #C3;
+static const field core::bool c7 = #C2;
+static const field core::bool c8 = #C2;
+static const field core::bool c9 = #C2;
+static const field core::bool c10 = #C3;
+static const field core::bool c11 = #C2;
+static const field core::bool c12 = #C2;
+static const field self::Class<core::int> e1 = #C4;
+static const field self::Class<core::List<core::int>> e2 = #C5;
+static const field self::Class<Null> e3 = #C6;
+static const field self::Class<core::int> e4 = #C7;
+static const field self::Class<core::int?> e5 = #C8;
+static const field self::Class<Null> e6 = #C6;
+static const field self::Class<core::int> e7 = #C4;
+static const field self::Class<core::int?> e8 = #C9;
+static const field self::Class<Null> e9 = #C10;
+static const field self::Class<core::int> e10 = #C7;
+static const field self::Class<core::int?> e11 = #C8;
+static const field self::Class<Null> e12 = #C6;
+static method main() → dynamic {
+  self::expect(null is{ForNonNullableByDefault} core::int?, #C2, "null is int?");
+  self::expect(null is{ForNonNullableByDefault} core::int, #C3, "null is int");
+  self::expect(null is{ForNonNullableByDefault} Null, #C2, "null is Null");
+  self::expect(null is{ForNonNullableByDefault} Never?, #C2, "null is Never?");
+  self::expect(null is{ForNonNullableByDefault} Never, #C3, "null is Never");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<core::int?>, #C2, "null is FutureOr<int?>");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<core::int>, #C3, "null is FutureOr<int>");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<core::int>?, #C2, "null is FutureOr<int>?");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<Null>, #C2, "null is FutureOr<Null>");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<Null>?, #C2, "null is FutureOr<Null>?");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<Never>, #C3, "null is FutureOr<Never>");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<Never?>, #C2, "null is FutureOr<Never?>");
+  self::expect(null is{ForNonNullableByDefault} FutureOr<Never>?, #C2, "null is FutureOr<Never>?");
+  self::expect(new self::Class::constructor1<core::int>(null).{self::Class::field}{core::bool}, #C4.{self::Class::field}{core::bool}, "Class<int>.constructor1(null).field");
+  self::expect(true, new self::Class::constructor1<core::int?>(null).{self::Class::field}{core::bool}, "new Class<int?>.constructor1(null).field");
+  self::expect(self::isWeakMode, #C5.{self::Class::field}{core::bool}, "const Class<List<int>>.constructor1(<Null>[null]).field");
+  self::expect(new self::Class::constructor1<Null>(null).{self::Class::field}{core::bool}, #C6.{self::Class::field}{core::bool}, "Class<Null>.constructor1(null).field");
+  self::expect(new self::Class::constructor2<core::int>(null).{self::Class::field}{core::bool}, #C7.{self::Class::field}{core::bool}, "Class<int>.constructor2(null).field");
+  self::expect(true, new self::Class::constructor2<core::int?>(null).{self::Class::field}{core::bool}, "new Class<int?>.constructor2(null).field");
+  self::expect(new self::Class::constructor2<core::int?>(null).{self::Class::field}{core::bool}, #C8.{self::Class::field}{core::bool}, "Class<int?>.constructor2(null).field");
+  self::expect(new self::Class::constructor2<Null>(null).{self::Class::field}{core::bool}, #C6.{self::Class::field}{core::bool}, "Class<Null>.constructor2(null).field");
+  self::expect(new self::Class::constructor3<core::int>(null).{self::Class::field}{core::bool}, #C4.{self::Class::field}{core::bool}, "Class<int>.constructor3(null).field");
+  self::expect(new self::Class::constructor3<core::int?>(null).{self::Class::field}{core::bool}, #C9.{self::Class::field}{core::bool}, "Class<int?>.constructor3(null).field");
+  self::expect(new self::Class::constructor3<core::int?>(null).{self::Class::field}{core::bool}, #C9.{self::Class::field}{core::bool}, "Class<int?>.constructor3(null).field");
+  self::expect(new self::Class::constructor3<Null>(null).{self::Class::field}{core::bool}, #C10.{self::Class::field}{core::bool}, "Class<Null>.constructor3(null).field");
+  self::expect(new self::Class::constructor4<core::int>(null).{self::Class::field}{core::bool}, #C7.{self::Class::field}{core::bool}, "Class<int>.constructor4(null).field");
+  self::expect(new self::Class::constructor4<core::int?>(null).{self::Class::field}{core::bool}, #C8.{self::Class::field}{core::bool}, "Class<int?>.constructor4(null).field");
+  self::expect(new self::Class::constructor4<Null>(null).{self::Class::field}{core::bool}, #C6.{self::Class::field}{core::bool}, "Class<Null>.constructor4(null).field");
+  con::test();
+}
+static method expect(dynamic expected, dynamic actual, core::String message) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual} for ${message}";
+}
+
+library;
+import self as con;
+import "constant_null_is.dart" as self;
+import "dart:core" as core;
+
+import "dart:async";
+import "org-dartlang-testcase:///constant_null_is.dart";
+
+static const field core::bool* d0 = #C3;
+static const field core::bool* d1 = #C2;
+static const field self::Class<core::int*>* d4 = #C4;
+static const field self::Class<Null>* d5 = #C6;
+static const field self::Class<core::int*>* d6 = #C7;
+static const field self::Class<Null>* d7 = #C6;
+static const field self::Class<core::int*>* d8 = #C4;
+static const field self::Class<Null>* d9 = #C10;
+static const field self::Class<core::int*>* d10 = #C7;
+static const field self::Class<Null>* d11 = #C6;
+static method test() → dynamic {
+  self::expect(null is core::int*, #C3, "null is int (opt-out)");
+  self::expect(null is Null, #C2, "null is Null");
+  self::expect(new self::Class::constructor1<core::int*>(null).{self::Class::field}{core::bool*}, #C4.{self::Class::field}{core::bool*}, "Class<int>.constructor1(null).field (opt-out)");
+  self::expect(new self::Class::constructor1<Null>(null).{self::Class::field}{core::bool*}, #C6.{self::Class::field}{core::bool*}, "Class<Null>.constructor1(null).field (opt-out)");
+  self::expect(new self::Class::constructor2<core::int*>(null).{self::Class::field}{core::bool*}, #C7.{self::Class::field}{core::bool*}, "Class<int>.constructor2(null).field (opt-out)");
+  self::expect(new self::Class::constructor2<Null>(null).{self::Class::field}{core::bool*}, #C6.{self::Class::field}{core::bool*}, "Class<Null>.constructor2(null).field (opt-out)");
+  self::expect(new self::Class::constructor3<core::int*>(null).{self::Class::field}{core::bool*}, #C4.{self::Class::field}{core::bool*}, "Class<int>.constructor3(null).field (opt-out)");
+  self::expect(new self::Class::constructor3<Null>(null).{self::Class::field}{core::bool*}, #C10.{self::Class::field}{core::bool*}, "Class<Null>.constructor3(null).field (opt-out)");
+  self::expect(new self::Class::constructor4<core::int*>(null).{self::Class::field}{core::bool*}, #C7.{self::Class::field}{core::bool*}, "Class<int>.constructor4(null).field (opt-out)");
+  self::expect(new self::Class::constructor4<Null>(null).{self::Class::field}{core::bool*}, #C6.{self::Class::field}{core::bool*}, "Class<Null>.constructor4(null).field (opt-out)");
+}
+
+constants  {
+  #C1 = <Null>[]
+  #C2 = true
+  #C3 = false
+  #C4 = self::Class<core::int*> {field:#C3}
+  #C5 = self::Class<core::List<core::int*>*> {field:#C2}
+  #C6 = self::Class<Null> {field:#C2}
+  #C7 = self::Class<core::int*> {field:#C2}
+  #C8 = self::Class<core::int?> {field:#C2}
+  #C9 = self::Class<core::int?> {field:#C3}
+  #C10 = self::Class<Null> {field:#C3}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///constant_null_is.dart:
+- Class.constructor1 (from org-dartlang-testcase:///constant_null_is.dart:39:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Class.constructor2 (from org-dartlang-testcase:///constant_null_is.dart:40:9)
+- Class.constructor3 (from org-dartlang-testcase:///constant_null_is.dart:41:9)
+- Class.constructor4 (from org-dartlang-testcase:///constant_null_is.dart:42:9)
+
+org-dartlang-testcase:///constant_null_is_lib.dart:
+- Class.constructor1 (from org-dartlang-testcase:///constant_null_is.dart:39:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Class.constructor2 (from org-dartlang-testcase:///constant_null_is.dart:40:9)
+- Class.constructor3 (from org-dartlang-testcase:///constant_null_is.dart:41:9)
+- Class.constructor4 (from org-dartlang-testcase:///constant_null_is.dart:42:9)
diff --git a/pkg/front_end/testcases/nnbd_mixed/constants.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/constants.dart.weak.modular.expect
new file mode 100644
index 0000000..f72fa11
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/constants.dart.weak.modular.expect
@@ -0,0 +1,104 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "constants_lib.dart" as con;
+
+import "org-dartlang-testcase:///constants_lib.dart" as lib;
+
+static const field (core::int) → core::int partialInstantiation = #C2;
+static const field con::Class<core::int> instance = #C4;
+static const field core::List<core::int> listLiteral = #C5;
+static const field core::Set<core::int> setLiteral = #C6;
+static const field core::Map<core::int, core::String> mapLiteral = #C8;
+static const field core::List<core::int> listConcatenation = #C5;
+static const field core::Set<core::int> setConcatenation = #C6;
+static const field core::Map<core::int, core::String> mapConcatenation = #C8;
+static const field core::bool partialInstantiationIdentical = #C9;
+static const field core::bool instanceIdentical = #C9;
+static const field core::bool listLiteralIdentical = #C9;
+static const field core::bool setLiteralIdentical = #C9;
+static const field core::bool mapLiteralIdentical = #C9;
+static const field core::bool listConcatenationIdentical = #C9;
+static const field core::bool setConcatenationIdentical = #C9;
+static const field core::bool mapConcatenationIdentical = #C9;
+static method main() → dynamic {
+  self::test(#C2, #C2);
+  self::test(#C4, #C4);
+  self::test(#C5, #C5);
+  self::test(#C6, #C6);
+  self::test(#C8, #C8);
+  self::test(#C5, #C5);
+  self::test(#C6, #C6);
+  self::test(#C8, #C8);
+  self::test(true, #C9);
+  self::test(true, #C9);
+  self::test(true, #C9);
+  self::test(true, #C9);
+  self::test(true, #C9);
+  self::test(true, #C9);
+  self::test(true, #C9);
+  self::test(true, #C9);
+}
+static method test(dynamic expected, dynamic actual) → dynamic {
+  core::print("test(${expected}, ${actual})");
+  if(!core::identical(expected, actual)) {
+    throw "Expected ${expected}, actual ${actual}";
+  }
+}
+
+library;
+import self as con;
+import "dart:core" as core;
+
+typedef F1<invariant T extends core::Object* = dynamic> = (T*) →* T*;
+typedef F2 = <T extends core::Object* = dynamic>(T*) →* T*;
+class Class<T extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field con::Class::T* field;
+  const constructor •(con::Class::T* field) → con::Class<con::Class::T*>*
+    : con::Class::field = field, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field (core::Object*, core::Object*) →* core::bool* c2 = #C10;
+static const field (core::int*) →* core::int* partialInstantiation = #C2;
+static const field con::Class<core::int*>* instance = #C4;
+static const field core::List<core::int*>* listLiteral = #C5;
+static const field core::Set<core::int*>* setLiteral = #C6;
+static const field core::Map<core::int*, core::String*>* mapLiteral = #C8;
+static const field core::List<core::int*>* listConcatenation = #C5;
+static const field core::Set<core::int*>* setConcatenation = #C6;
+static const field core::Map<core::int*, core::String*>* mapConcatenation = #C8;
+static method id<T extends core::Object* = dynamic>(con::id::T* t) → con::id::T*
+  return t;
+
+constants  {
+  #C1 = static-tearoff con::id
+  #C2 = instantiation #C1 <core::int*>
+  #C3 = 0
+  #C4 = con::Class<core::int*> {field:#C3}
+  #C5 = <core::int*>[#C3]
+  #C6 = <core::int*>{#C3}
+  #C7 = "foo"
+  #C8 = <core::int*, core::String*>{#C3:#C7)
+  #C9 = true
+  #C10 = static-tearoff core::identical
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///constants.dart:
+- Class. (from org-dartlang-testcase:///constants_lib.dart:10:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+
+org-dartlang-testcase:///constants_lib.dart:
+- Class. (from org-dartlang-testcase:///constants_lib.dart:10:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd_mixed/covariant_from_opt_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/covariant_from_opt_in.dart.weak.modular.expect
new file mode 100644
index 0000000..a18752a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/covariant_from_opt_in.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/covariant_from_opt_in.dart:11:27: Error: The parameter 'cls' of the method 'SubClass.invariant' has type 'SubClass', which does not match the corresponding type, 'Class', in the overridden method, 'Class.invariant'.
+//  - 'SubClass' is from 'pkg/front_end/testcases/nnbd_mixed/covariant_from_opt_in.dart'.
+//  - 'Class' is from 'pkg/front_end/testcases/nnbd_mixed/covariant_from_opt_in_lib.dart'.
+// Change to a supertype of 'Class', or, for a covariant parameter, a subtype.
+//   void invariant(SubClass cls) {} // error
+//                           ^
+// pkg/front_end/testcases/nnbd_mixed/covariant_from_opt_in_lib.dart:9:8: Context: This is the overridden method ('invariant').
+//   void invariant(Class cls);
+//        ^
+//
+import self as self;
+import "covariant_from_opt_in_lib.dart" as cov;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///covariant_from_opt_in_lib.dart";
+
+abstract class _SubClass&Class&Mixin = cov::Class with cov::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_SubClass&Class&Mixin*
+    : super cov::Class::•()
+    ;
+  abstract member-signature method covariant(covariant-by-declaration cov::Class* cls) → void; -> cov::Class::covariant
+  abstract member-signature method invariant(cov::Class* cls) → void; -> cov::Class::invariant
+  abstract member-signature method contravariant(cov::Class* cls) → void; -> cov::Class::contravariant
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class SubClass extends self::_SubClass&Class&Mixin {
+  synthetic constructor •() → self::SubClass*
+    : super self::_SubClass&Class&Mixin::•()
+    ;
+  method covariant(covariant-by-declaration self::SubClass* cls) → void {}
+  method invariant(self::SubClass* cls) → void {}
+  method contravariant(core::Object* cls) → void {}
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as cov;
+import "dart:core" as core;
+
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+}
+abstract class Class extends core::Object {
+  synthetic constructor •() → cov::Class
+    : super core::Object::•()
+    ;
+  abstract method covariant(covariant-by-declaration cov::Class cls) → void;
+  abstract method invariant(cov::Class cls) → void;
+  abstract method contravariant(cov::Class cls) → void;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/cyclic_typedef.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/cyclic_typedef.dart.weak.modular.expect
new file mode 100644
index 0000000..83322f3
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/cyclic_typedef.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/cyclic_typedef.dart:12:7: Error: Generic type 'Hest2' can't be used without type arguments in the bounds of its own type variables. It is referenced indirectly through 'Fisk2'.
+// Try providing type arguments to 'Fisk2' here or to some other raw types in the bounds along the reference chain.
+// class Hest2<TypeX extends Fisk2> {}
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/cyclic_typedef.dart:12:13: Context: Bound of this variable references raw type 'Fisk2'.
+// class Hest2<TypeX extends Fisk2> {}
+//             ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/cyclic_typedef_lib.dart:14:31: Context: Bound of this variable references raw type 'Hest2'.
+// typedef Fisk2 = void Function<TypeY extends Hest2>();
+//                               ^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/cyclic_typedef.dart:14:9: Error: Generic type 'Fisk1' can't be used without type arguments in the bounds of its own type variables. It is referenced indirectly through 'Hest1'.
+// Try providing type arguments to 'Hest1' here or to some other raw types in the bounds along the reference chain.
+// typedef Fisk1 = void Function<TypeY extends Hest1>();
+//         ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/cyclic_typedef.dart:14:31: Context: Bound of this variable references raw type 'Hest1'.
+// typedef Fisk1 = void Function<TypeY extends Hest1>();
+//                               ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/cyclic_typedef_lib.dart:12:13: Context: Bound of this variable references raw type 'Fisk1'.
+// class Hest1<TypeX extends Fisk1> {}
+//             ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///cyclic_typedef_lib.dart";
+
+typedef Fisk1 = <TypeY extends core::Object? = dynamic>() → void;
+class Hest2<TypeX extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Hest2<self::Hest2::TypeX%>
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/cyclic_typedef_lib.dart:12:13: Error: Type variables can't have generic function types in their bounds.
+// class Hest1<TypeX extends Fisk1> {}
+//             ^^^^^
+//
+import self as self2;
+import "cyclic_typedef.dart" as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///cyclic_typedef.dart";
+
+typedef Fisk2 = <TypeY extends self::Hest2<dynamic> = dynamic>() → void;
+class Hest1<TypeX extends <TypeY extends core::Object? = dynamic>() → void = dynamic> extends core::Object {
+  synthetic constructor •() → self2::Hest1<self2::Hest1::TypeX>
+    : super core::Object::•()
+    ;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/error_on_recompile_with_no_change/main.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/error_on_recompile_with_no_change/main.dart.weak.modular.expect
new file mode 100644
index 0000000..ccc539a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/error_on_recompile_with_no_change/main.dart.weak.modular.expect
@@ -0,0 +1,118 @@
+library;
+import self as self;
+import "object_lib.dart" as obj;
+import "main_lib1.dart" as mai;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///object_lib.dart";
+import "org-dartlang-testcase:///main_lib1.dart";
+
+class AdaptorElement extends obj::RenderObject {
+  synthetic constructor •() → self::AdaptorElement*
+    : super obj::RenderObject::•()
+    ;
+  get renderObject() → mai::Adaptor*
+    return super.{obj::RenderObject::renderObject} as{TypeError} mai::Adaptor*;
+  method foo() → void {
+    core::print(this.{self::AdaptorElement::renderObject}{mai::Adaptor*}.{mai::_Adaptor&RenderFoo&LibMixin::constraints}{obj::FooConstraints*}.{obj::FooConstraints::axis}{core::String*});
+  }
+  abstract member-signature get constraints() → obj::Constraints*; -> obj::RenderObject::constraints
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as obj;
+import "dart:core" as core;
+
+class RenderFoo extends obj::RenderObject {
+  synthetic constructor •() → obj::RenderFoo
+    : super obj::RenderObject::•()
+    ;
+  get constraints() → obj::FooConstraints
+    return super.{obj::RenderObject::constraints} as{ForNonNullableByDefault} obj::FooConstraints;
+}
+class FooConstraints extends obj::Constraints {
+  synthetic constructor •() → obj::FooConstraints
+    : super obj::Constraints::•()
+    ;
+  get axis() → core::String
+    return "hello";
+}
+class Constraints extends core::Object {
+  synthetic constructor •() → obj::Constraints
+    : super core::Object::•()
+    ;
+}
+class RenderObject extends core::Object {
+  synthetic constructor •() → obj::RenderObject
+    : super core::Object::•()
+    ;
+  get constraints() → obj::Constraints
+    return new obj::Constraints::•();
+  get renderObject() → obj::RenderObject
+    return this;
+}
+
+library;
+import self as mai;
+import "object_lib.dart" as obj;
+import "main_lib2.dart" as mai2;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///object_lib.dart";
+import "org-dartlang-testcase:///main_lib2.dart";
+
+abstract class _Adaptor&RenderFoo&LibMixin = obj::RenderFoo with mai2::LibMixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → mai::_Adaptor&RenderFoo&LibMixin*
+    : super obj::RenderFoo::•()
+    ;
+  abstract member-signature get constraints() → obj::FooConstraints*; -> obj::RenderFoo::constraints
+  abstract member-signature get renderObject() → obj::RenderObject*; -> obj::RenderObject::renderObject
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Adaptor extends mai::_Adaptor&RenderFoo&LibMixin {
+  synthetic constructor •() → mai::Adaptor*
+    : super mai::_Adaptor&RenderFoo&LibMixin::•()
+    ;
+}
+
+library;
+import self as mai2;
+import "object_lib.dart" as obj;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///object_lib.dart";
+
+abstract class LibMixin extends obj::RenderObject /*isMixinDeclaration*/  {
+  abstract member-signature get constraints() → obj::Constraints*; -> obj::RenderObject::constraints
+  abstract member-signature get renderObject() → obj::RenderObject*; -> obj::RenderObject::renderObject
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/experiment_release_version/main.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/experiment_release_version/main.dart.weak.modular.expect
new file mode 100644
index 0000000..d4de37b
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/experiment_release_version/main.dart.weak.modular.expect
@@ -0,0 +1,95 @@
+//
+// Problems outside component:
+//
+// pkg/front_end/testcases/nnbd_mixed/experiment_release_version/allowed_package/lib/versioned_2_8_lib.dart:7:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.9 or higher.
+// int? versioned_2_8_AllowedPackage; // error
+//    ^
+// pkg/front_end/testcases/nnbd_mixed/experiment_release_version/allowed_package/lib/versioned_2_8_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.8
+// ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/experiment_release_version/not_allowed_package/lib/unversioned_lib.dart:5:4: Error: Null safety features are disabled for this library.
+// Try removing the package language version or setting the language version to 2.10 or higher.
+// int? versionedUnallowedPackage; // error
+//    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/experiment_release_version/not_allowed_package/lib/versioned_2_8_lib.dart:7:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.10 or higher.
+// int? versioned_2_8_AllowedPackage; // error
+//    ^
+// pkg/front_end/testcases/nnbd_mixed/experiment_release_version/not_allowed_package/lib/versioned_2_8_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.8
+// ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/experiment_release_version/not_allowed_package/lib/versioned_2_9_lib.dart:7:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.10 or higher.
+// int? versioned_2_9_AllowedPackage; // error
+//    ^
+// pkg/front_end/testcases/nnbd_mixed/experiment_release_version/not_allowed_package/lib/versioned_2_9_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.9
+// ^^^^^^^^^^^^
+//
+library /*isNonNullableByDefault*/;
+import self as self;
+
+import "package:allowed_package/unversioned_lib.dart";
+import "package:allowed_package/versioned_2_8_lib.dart";
+import "package:allowed_package/versioned_2_9_lib.dart";
+import "package:allowed_package/versioned_2_10_lib.dart";
+import "package:not_allowed_package/unversioned_lib.dart";
+import "package:not_allowed_package/versioned_2_8_lib.dart";
+import "package:not_allowed_package/versioned_2_9_lib.dart";
+import "package:not_allowed_package/versioned_2_10_lib.dart";
+import "org-dartlang-testcase:///unversioned_lib.dart";
+import "org-dartlang-testcase:///versioned_2_8_lib.dart";
+import "org-dartlang-testcase:///versioned_2_9_lib.dart";
+import "org-dartlang-testcase:///versioned_2_10_lib.dart";
+
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as self2;
+import "dart:core" as core;
+
+static field core::int? unversionedLibrary;
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/experiment_release_version/versioned_2_8_lib.dart:7:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.10 or higher.
+// int? versioned_2_8_Library; // error
+//    ^
+// pkg/front_end/testcases/nnbd_mixed/experiment_release_version/versioned_2_8_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.8
+// ^^^^^^^^^^^^
+//
+import self as self3;
+import "dart:core" as core;
+
+static field core::int? versioned_2_8_Library;
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/experiment_release_version/versioned_2_9_lib.dart:7:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.10 or higher.
+// int? versioned_2_9_Library; // error
+//    ^
+// pkg/front_end/testcases/nnbd_mixed/experiment_release_version/versioned_2_9_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.9
+// ^^^^^^^^^^^^
+//
+import self as self4;
+import "dart:core" as core;
+
+static field core::int? versioned_2_9_Library;
+
+library /*isNonNullableByDefault*/;
+import self as self5;
+import "dart:core" as core;
+
+static field core::int? versioned_2_10_Library;
diff --git a/pkg/front_end/testcases/nnbd_mixed/export_from_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/export_from_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..a081994
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/export_from_opt_out.dart.weak.modular.expect
@@ -0,0 +1,164 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/export_from_opt_out.dart:6:1: Error: Null safe libraries are not allowed to export declarations from of opt-out libraries.
+// export 'export_from_opt_out_lib1.dart';
+// ^
+//
+// pkg/front_end/testcases/nnbd_mixed/export_from_opt_out.dart:10:1: Error: Null safe libraries are not allowed to export declarations from of opt-out libraries.
+// export 'export_from_opt_out_lib2.dart' hide legacyMethod2;
+// ^
+//
+// pkg/front_end/testcases/nnbd_mixed/export_from_opt_out.dart:13:1: Error: Null safe libraries are not allowed to export declarations from of opt-out libraries.
+// export 'export_from_opt_out_lib3.dart' show LegacyClass2;
+// ^
+//
+// pkg/front_end/testcases/nnbd_mixed/export_from_opt_out.dart:16:1: Error: Null safe libraries are not allowed to export declarations from of opt-out libraries.
+// export 'export_from_opt_out_lib3.dart' show legacyMethod1;
+// ^
+//
+// pkg/front_end/testcases/nnbd_mixed/export_from_opt_out.dart:19:1: Error: Null safe libraries are not allowed to export declarations from of opt-out libraries.
+// export 'export_from_opt_out_lib3.dart' show LegacyExtension;
+// ^
+//
+// pkg/front_end/testcases/nnbd_mixed/export_from_opt_out.dart:22:1: Error: Null safe libraries are not allowed to export declarations from of opt-out libraries.
+// export 'export_from_opt_out_lib3.dart' show LegacyTypedef;
+// ^
+//
+import self as self;
+import "export_from_opt_out_lib1.dart" as exp;
+import "export_from_opt_out_lib2.dart" as exp2;
+import "export_from_opt_out_lib3.dart" as exp3;
+import "export_from_opt_out_lib5.dart" as exp4;
+additionalExports = (exp::LegacyClass1,
+  exp2::LegacyClass3,
+  exp2::LegacyClass4,
+  exp3::LegacyClass2,
+  exp3::legacyMethod1,
+  exp3::LegacyExtension,
+  exp3::LegacyTypedef,
+  exp4::NnbdClass1,
+  exp4::NnbdClass2)
+
+export "org-dartlang-testcase:///export_from_opt_out_lib1.dart";
+export "org-dartlang-testcase:///export_from_opt_out_lib2.dart" hide legacyMethod2;
+export "org-dartlang-testcase:///export_from_opt_out_lib3.dart" show LegacyClass2;
+export "org-dartlang-testcase:///export_from_opt_out_lib3.dart" show legacyMethod1;
+export "org-dartlang-testcase:///export_from_opt_out_lib3.dart" show LegacyExtension;
+export "org-dartlang-testcase:///export_from_opt_out_lib3.dart" show LegacyTypedef;
+export "org-dartlang-testcase:///export_from_opt_out_lib3.dart" show NnbdClass1;
+export "org-dartlang-testcase:///export_from_opt_out_lib3.dart" hide LegacyClass2, LegacyExtension, LegacyTypedef, legacyMethod1;
+export "org-dartlang-testcase:///export_from_opt_out_lib4.dart";
+export "org-dartlang-testcase:///export_from_opt_out_lib5.dart";
+
+static method main() → dynamic {}
+
+library;
+import self as exp;
+import "dart:core" as core;
+
+class LegacyClass1 extends core::Object {
+  synthetic constructor •() → exp::LegacyClass1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+library;
+import self as exp2;
+import "dart:core" as core;
+
+class LegacyClass3 extends core::Object {
+  synthetic constructor •() → exp2::LegacyClass3*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass4 extends core::Object {
+  synthetic constructor •() → exp2::LegacyClass4*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method legacyMethod2() → dynamic {}
+
+library;
+import self as exp3;
+import "dart:core" as core;
+import "export_from_opt_out_lib5.dart" as exp4;
+additionalExports = (exp4::NnbdClass1,
+  exp4::NnbdClass2)
+
+export "org-dartlang-testcase:///export_from_opt_out_lib5.dart";
+
+typedef LegacyTypedef = () →* void;
+class LegacyClass2 extends core::Object {
+  synthetic constructor •() → exp3::LegacyClass2*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension LegacyExtension on core::String* {
+}
+static method legacyMethod1() → dynamic {}
+
+library;
+import self as self2;
+import "export_from_opt_out_lib5.dart" as exp4;
+additionalExports = (exp4::NnbdClass1,
+  exp4::NnbdClass2)
+
+export "org-dartlang-testcase:///export_from_opt_out_lib5.dart";
+
+
+library /*isNonNullableByDefault*/;
+import self as exp4;
+import "dart:core" as core;
+
+class NnbdClass1 extends core::Object {
+  synthetic constructor •() → exp4::NnbdClass1
+    : super core::Object::•()
+    ;
+}
+class NnbdClass2 extends core::Object {
+  synthetic constructor •() → exp4::NnbdClass2
+    : super core::Object::•()
+    ;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/flutter_issue_63029/flutter_issue_63029.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/flutter_issue_63029/flutter_issue_63029.dart.weak.modular.expect
new file mode 100644
index 0000000..ab022ec
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/flutter_issue_63029/flutter_issue_63029.dart.weak.modular.expect
@@ -0,0 +1,76 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "flutter_issue_63029_lib1.dart" as flu;
+import "flutter_issue_63029_lib2.dart" as flu2;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///flutter_issue_63029_lib1.dart";
+import "org-dartlang-testcase:///flutter_issue_63029_lib2.dart";
+
+class E extends flu::A {
+  synthetic constructor •() → self::E
+    : super flu::A::•()
+    ;
+}
+abstract class _F&B&D = flu::B<self::E> with flu2::D<self::E> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_F&B&D
+    : super flu::B::•()
+    ;
+  abstract member-signature operator /*isLegacy*/ ==(dynamic other) → core::bool*; -> core::Object::==
+}
+class F extends self::_F&B&D {
+  synthetic constructor •() → self::F
+    : super self::_F&B&D::•()
+    ;
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as flu;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → flu::A
+    : super core::Object::•()
+    ;
+}
+abstract class B<T extends flu::A> extends core::Object {
+  synthetic constructor •() → flu::B<flu::B::T>
+    : super core::Object::•()
+    ;
+}
+
+library;
+import self as flu2;
+import "dart:core" as core;
+import "flutter_issue_63029_lib1.dart" as flu;
+
+import "org-dartlang-testcase:///flutter_issue_63029_lib1.dart";
+
+class C extends core::Object {
+  synthetic constructor •() → flu2::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D<T extends flu::A*> extends flu::B<flu2::D::T*> implements flu2::C /*isMixinDeclaration*/  {
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/generic_override.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/generic_override.dart.weak.modular.expect
new file mode 100644
index 0000000..71759ac
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/generic_override.dart.weak.modular.expect
@@ -0,0 +1,199 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/generic_override.dart:39:8: Error: Declared bound 'Object?' of type variable 'T' of 'Class2.method4b' doesn't match the bound 'Object' on overridden method 'Class1.method4b'.
+//  - 'Object' is from 'dart:core'.
+//   void method4b<T extends Object?>(); // error
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/generic_override.dart:19:8: Context: This is the overridden method ('method4b').
+//   void method4b<T extends Object>();
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/generic_override.dart:40:8: Error: Declared bound 'Object' of type variable 'T' of 'Class2.method4c' doesn't match the bound 'Object?' on overridden method 'Class1.method4c'.
+//  - 'Object' is from 'dart:core'.
+//   void method4c<T extends Object>(); // error
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/generic_override.dart:20:8: Context: This is the overridden method ('method4c').
+//   void method4c<T extends Object?>();
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/generic_override.dart:43:8: Error: Declared bound 'Class1?' of type variable 'T' of 'Class2.method5b' doesn't match the bound 'Class1' on overridden method 'Class1.method5b'.
+//  - 'Class1' is from 'pkg/front_end/testcases/nnbd_mixed/generic_override.dart'.
+//   void method5b<T extends Class1?>(); // error
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/generic_override.dart:23:8: Context: This is the overridden method ('method5b').
+//   void method5b<T extends Class1>();
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/generic_override.dart:44:8: Error: Declared bound 'Class1' of type variable 'T' of 'Class2.method5c' doesn't match the bound 'Class1?' on overridden method 'Class1.method5c'.
+//  - 'Class1' is from 'pkg/front_end/testcases/nnbd_mixed/generic_override.dart'.
+//   void method5c<T extends Class1>(); // error
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/generic_override.dart:24:8: Context: This is the overridden method ('method5c').
+//   void method5c<T extends Class1?>();
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+import "generic_override_lib.dart" as gen;
+
+import "org-dartlang-testcase:///generic_override_lib.dart";
+
+abstract class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+  abstract method method1a<T extends core::Object? = dynamic>() → void;
+  abstract method method1b<T extends core::Object? = dynamic>() → void;
+  abstract method method1c<T extends core::Object? = dynamic>() → void;
+  abstract method method2a<T extends core::Object?>() → void;
+  abstract method method2b<T extends core::Object?>() → void;
+  abstract method method2c<T extends core::Object?>() → void;
+  abstract method method3a<T extends dynamic>() → void;
+  abstract method method3b<T extends dynamic>() → void;
+  abstract method method3c<T extends dynamic>() → void;
+  abstract method method4a<T extends core::Object>() → void;
+  abstract method method4b<T extends core::Object>() → void;
+  abstract method method4c<T extends core::Object?>() → void;
+  abstract method method5a<T extends self::Class1>() → void;
+  abstract method method5b<T extends self::Class1>() → void;
+  abstract method method5c<T extends self::Class1?>() → void;
+}
+abstract class Class2 extends self::Class1 {
+  synthetic constructor •() → self::Class2
+    : super self::Class1::•()
+    ;
+  abstract method method1a<T extends core::Object? = dynamic>() → void;
+  abstract method method1b<T extends core::Object?>() → void;
+  abstract method method1c<T extends dynamic>() → void;
+  abstract method method2a<T extends core::Object? = dynamic>() → void;
+  abstract method method2b<T extends core::Object?>() → void;
+  abstract method method2c<T extends dynamic>() → void;
+  abstract method method3a<T extends core::Object? = dynamic>() → void;
+  abstract method method3b<T extends core::Object?>() → void;
+  abstract method method3c<T extends dynamic>() → void;
+  abstract method method4a<T extends core::Object>() → void;
+  abstract method method4b<T extends core::Object?>() → void;
+  abstract method method4c<T extends core::Object>() → void;
+  abstract method method5a<T extends self::Class1>() → void;
+  abstract method method5b<T extends self::Class1?>() → void;
+  abstract method method5c<T extends self::Class1>() → void;
+}
+abstract class Class3 extends gen::LegacyClass1 {
+  synthetic constructor •() → self::Class3
+    : super gen::LegacyClass1::•()
+    ;
+  abstract method method1a<T extends core::Object? = dynamic>() → void;
+  abstract method method1b<T extends core::Object?>() → void;
+  abstract method method1c<T extends dynamic>() → void;
+  abstract method method2a<T extends core::Object? = dynamic>() → void;
+  abstract method method2b<T extends core::Object?>() → void;
+  abstract method method2c<T extends dynamic>() → void;
+  abstract method method3a<T extends core::Object? = dynamic>() → void;
+  abstract method method3b<T extends core::Object?>() → void;
+  abstract method method3c<T extends dynamic>() → void;
+  abstract method method4a<T extends core::Object>() → void;
+  abstract method method4b<T extends core::Object?>() → void;
+  abstract method method4c<T extends core::Object>() → void;
+  abstract method method5a<T extends self::Class1>() → void;
+  abstract method method5b<T extends self::Class1?>() → void;
+  abstract method method5c<T extends self::Class1>() → void;
+}
+static method main() → dynamic {}
+
+library;
+import self as gen;
+import "dart:core" as core;
+import "generic_override.dart" as self;
+
+import "org-dartlang-testcase:///generic_override.dart";
+
+abstract class LegacyClass1 extends core::Object {
+  synthetic constructor •() → gen::LegacyClass1*
+    : super core::Object::•()
+    ;
+  abstract method method1a<T extends core::Object* = dynamic>() → void;
+  abstract method method1b<T extends core::Object* = dynamic>() → void;
+  abstract method method1c<T extends core::Object* = dynamic>() → void;
+  abstract method method2a<T extends core::Object*>() → void;
+  abstract method method2b<T extends core::Object*>() → void;
+  abstract method method2c<T extends core::Object*>() → void;
+  abstract method method3a<T extends dynamic>() → void;
+  abstract method method3b<T extends dynamic>() → void;
+  abstract method method3c<T extends dynamic>() → void;
+  abstract method method4a<T extends core::Object*>() → void;
+  abstract method method4b<T extends core::Object*>() → void;
+  abstract method method4c<T extends core::Object*>() → void;
+  abstract method method5a<T extends self::Class1*>() → void;
+  abstract method method5b<T extends self::Class1*>() → void;
+  abstract method method5c<T extends self::Class1*>() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class LegacyClass2 extends self::Class1 {
+  synthetic constructor •() → gen::LegacyClass2*
+    : super self::Class1::•()
+    ;
+  abstract method method1a<T extends core::Object* = dynamic>() → void;
+  abstract method method1b<T extends core::Object*>() → void;
+  abstract method method1c<T extends dynamic>() → void;
+  abstract method method2a<T extends core::Object* = dynamic>() → void;
+  abstract method method2b<T extends core::Object*>() → void;
+  abstract method method2c<T extends dynamic>() → void;
+  abstract method method3a<T extends core::Object* = dynamic>() → void;
+  abstract method method3b<T extends core::Object*>() → void;
+  abstract method method3c<T extends dynamic>() → void;
+  abstract method method4a<T extends core::Object*>() → void;
+  abstract method method4b<T extends core::Object*>() → void;
+  abstract method method4c<T extends core::Object*>() → void;
+  abstract method method5a<T extends self::Class1*>() → void;
+  abstract method method5b<T extends self::Class1*>() → void;
+  abstract method method5c<T extends self::Class1*>() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class LegacyClass3 extends self::Class1 {
+  synthetic constructor •() → gen::LegacyClass3*
+    : super self::Class1::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature method method1a<T extends core::Object* = dynamic>() → void; -> self::Class1::method1a
+  abstract member-signature method method1b<T extends core::Object* = dynamic>() → void; -> self::Class1::method1b
+  abstract member-signature method method1c<T extends core::Object* = dynamic>() → void; -> self::Class1::method1c
+  abstract member-signature method method2a<T extends core::Object*>() → void; -> self::Class1::method2a
+  abstract member-signature method method2b<T extends core::Object*>() → void; -> self::Class1::method2b
+  abstract member-signature method method2c<T extends core::Object*>() → void; -> self::Class1::method2c
+  abstract member-signature method method4a<T extends core::Object*>() → void; -> self::Class1::method4a
+  abstract member-signature method method4b<T extends core::Object*>() → void; -> self::Class1::method4b
+  abstract member-signature method method4c<T extends core::Object*>() → void; -> self::Class1::method4c
+  abstract member-signature method method5a<T extends self::Class1*>() → void; -> self::Class1::method5a
+  abstract member-signature method method5b<T extends self::Class1*>() → void; -> self::Class1::method5b
+  abstract member-signature method method5c<T extends self::Class1*>() → void; -> self::Class1::method5c
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_extends_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_extends_field.dart.weak.modular.expect
new file mode 100644
index 0000000..bb1a80e
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_extends_field.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class AbstractSuper extends core::Object {
+  field core::int extendedConcreteField = 0;
+  field core::int declaredConcreteExtendsConcreteField = 0;
+  field core::int declaredAbstractExtendsConcreteField = 0;
+  synthetic constructor •() → self::AbstractSuper
+    : super core::Object::•()
+    ;
+  abstract get extendedAbstractField() → core::int;
+  abstract set extendedAbstractField(core::int #externalFieldValue) → void;
+  abstract get declaredConcreteExtendsAbstractField() → core::int;
+  abstract set declaredConcreteExtendsAbstractField(core::int #externalFieldValue) → void;
+  abstract get declaredAbstractExtendsAbstractField() → core::int;
+  abstract set declaredAbstractExtendsAbstractField(core::int #externalFieldValue) → void;
+}
+abstract class AbstractClass extends self::AbstractSuper {
+  field core::int declaredConcreteField = 0;
+  field core::int declaredConcreteExtendsConcreteField = 0;
+  field core::int declaredConcreteExtendsAbstractField = 0;
+  synthetic constructor •() → self::AbstractClass
+    : super self::AbstractSuper::•()
+    ;
+  abstract get declaredAbstractField() → core::int;
+  abstract set declaredAbstractField(core::int #externalFieldValue) → void;
+  abstract get declaredAbstractExtendsConcreteField() → core::int;
+  abstract set declaredAbstractExtendsConcreteField(core::int #externalFieldValue) → void;
+  abstract get declaredAbstractExtendsAbstractField() → core::int;
+  abstract set declaredAbstractExtendsAbstractField(core::int #externalFieldValue) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_extends_final_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_extends_final_field.dart.weak.modular.expect
new file mode 100644
index 0000000..f4368dd
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_extends_final_field.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class AbstractSuper extends core::Object {
+  final field core::int extendedConcreteField = 0;
+  final field core::int declaredConcreteExtendsConcreteField = 0;
+  final field core::int declaredAbstractExtendsConcreteField = 0;
+  synthetic constructor •() → self::AbstractSuper
+    : super core::Object::•()
+    ;
+  abstract get extendedAbstractField() → core::int;
+  abstract get declaredConcreteExtendsAbstractField() → core::int;
+  abstract get declaredAbstractExtendsAbstractField() → core::int;
+}
+abstract class AbstractClass extends self::AbstractSuper {
+  final field core::int declaredConcreteField = 0;
+  final field core::int declaredConcreteExtendsConcreteField = 0;
+  final field core::int declaredConcreteExtendsAbstractField = 0;
+  synthetic constructor •() → self::AbstractClass
+    : super self::AbstractSuper::•()
+    ;
+  abstract get declaredAbstractField() → core::int;
+  abstract get declaredAbstractExtendsConcreteField() → core::int;
+  abstract get declaredAbstractExtendsAbstractField() → core::int;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_extends_getter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_extends_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..bd5fdb7
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_extends_getter.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class AbstractSuper extends core::Object {
+  synthetic constructor •() → self::AbstractSuper
+    : super core::Object::•()
+    ;
+  get extendedConcreteGetter() → core::int
+    return 0;
+  abstract get extendedAbstractGetter() → core::int;
+  get declaredConcreteExtendsConcreteGetter() → core::int
+    return 0;
+  get declaredAbstractExtendsConcreteGetter() → core::int
+    return 0;
+  abstract get declaredConcreteExtendsAbstractGetter() → core::int;
+  abstract get declaredAbstractExtendsAbstractGetter() → core::int;
+}
+abstract class AbstractClass extends self::AbstractSuper {
+  synthetic constructor •() → self::AbstractClass
+    : super self::AbstractSuper::•()
+    ;
+  get declaredConcreteGetter() → core::int
+    return 0;
+  abstract get declaredAbstractGetter() → core::int;
+  get declaredConcreteExtendsConcreteGetter() → core::int
+    return 0;
+  abstract get declaredAbstractExtendsConcreteGetter() → core::int;
+  get declaredConcreteExtendsAbstractGetter() → core::int
+    return 0;
+  abstract get declaredAbstractExtendsAbstractGetter() → core::int;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_extends_method.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_extends_method.dart.weak.modular.expect
new file mode 100644
index 0000000..4f4c28e
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_extends_method.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class AbstractSuper extends core::Object {
+  synthetic constructor •() → self::AbstractSuper
+    : super core::Object::•()
+    ;
+  method extendedConcreteMethod() → void {}
+  abstract method extendedAbstractMethod() → void;
+  method declaredConcreteExtendsConcreteMethod() → void {}
+  method declaredAbstractExtendsConcreteMethod() → void {}
+  abstract method declaredConcreteExtendsAbstractMethod() → void;
+  abstract method declaredAbstractExtendsAbstractMethod() → void;
+}
+abstract class AbstractClass extends self::AbstractSuper {
+  synthetic constructor •() → self::AbstractClass
+    : super self::AbstractSuper::•()
+    ;
+  method declaredConcreteMethod() → void {}
+  abstract method declaredAbstractMethod() → void;
+  method declaredConcreteExtendsConcreteMethod() → void {}
+  abstract method declaredAbstractExtendsConcreteMethod() → void;
+  method declaredConcreteExtendsAbstractMethod() → void {}
+  abstract method declaredAbstractExtendsAbstractMethod() → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_extends_setter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_extends_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..c43f685
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_extends_setter.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class AbstractSuper extends core::Object {
+  synthetic constructor •() → self::AbstractSuper
+    : super core::Object::•()
+    ;
+  set extendedConcreteSetter(core::int value) → void {}
+  abstract set extendedAbstractSetter(core::int value) → void;
+  set declaredConcreteExtendsConcreteSetter(core::int value) → void {}
+  set declaredAbstractExtendsConcreteSetter(core::int value) → void {}
+  abstract set declaredConcreteExtendsAbstractSetter(core::int value) → void;
+  abstract set declaredAbstractExtendsAbstractSetter(core::int value) → void;
+}
+abstract class AbstractClass extends self::AbstractSuper {
+  synthetic constructor •() → self::AbstractClass
+    : super self::AbstractSuper::•()
+    ;
+  set declaredConcreteSetter(core::int value) → void {}
+  abstract set declaredAbstractSetter(core::int value) → void;
+  set declaredConcreteExtendsConcreteSetter(core::int value) → void {}
+  abstract set declaredAbstractExtendsConcreteSetter(core::int value) → void;
+  set declaredConcreteExtendsAbstractSetter(core::int value) → void {}
+  abstract set declaredAbstractExtendsAbstractSetter(core::int value) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_implements_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_implements_field.dart.weak.modular.expect
new file mode 100644
index 0000000..0cdcd41
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_implements_field.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  field core::int implementedConcreteField = 0;
+  field core::int declaredConcreteImplementsConcreteField = 0;
+  field core::int declaredAbstractImplementsConcreteField = 0;
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  abstract get implementedAbstractField() → core::int;
+  abstract set implementedAbstractField(core::int #externalFieldValue) → void;
+  abstract get declaredConcreteImplementsAbstractField() → core::int;
+  abstract set declaredConcreteImplementsAbstractField(core::int #externalFieldValue) → void;
+  abstract get declaredAbstractImplementsAbstractField() → core::int;
+  abstract set declaredAbstractImplementsAbstractField(core::int #externalFieldValue) → void;
+}
+abstract class AbstractClass extends core::Object implements self::Interface {
+  field core::int declaredConcreteField = 0;
+  field core::int declaredConcreteImplementsConcreteField = 0;
+  field core::int declaredConcreteImplementsAbstractField = 0;
+  synthetic constructor •() → self::AbstractClass
+    : super core::Object::•()
+    ;
+  abstract get declaredAbstractField() → core::int;
+  abstract set declaredAbstractField(core::int #externalFieldValue) → void;
+  abstract get declaredAbstractImplementsConcreteField() → core::int;
+  abstract set declaredAbstractImplementsConcreteField(core::int #externalFieldValue) → void;
+  abstract get declaredAbstractImplementsAbstractField() → core::int;
+  abstract set declaredAbstractImplementsAbstractField(core::int #externalFieldValue) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_implements_final_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_implements_final_field.dart.weak.modular.expect
new file mode 100644
index 0000000..e1f92ea
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_implements_final_field.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  final field core::int implementedConcreteField = 0;
+  final field core::int declaredConcreteImplementsConcreteField = 0;
+  final field core::int declaredAbstractImplementsConcreteField = 0;
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  abstract get implementedAbstractField() → core::int;
+  abstract get declaredConcreteImplementsAbstractField() → core::int;
+  abstract get declaredAbstractImplementsAbstractField() → core::int;
+}
+abstract class AbstractClass extends core::Object implements self::Interface {
+  final field core::int declaredConcreteField = 0;
+  final field core::int declaredConcreteImplementsConcreteField = 0;
+  final field core::int declaredConcreteImplementsAbstractField = 0;
+  synthetic constructor •() → self::AbstractClass
+    : super core::Object::•()
+    ;
+  abstract get declaredAbstractField() → core::int;
+  abstract get declaredAbstractImplementsConcreteField() → core::int;
+  abstract get declaredAbstractImplementsAbstractField() → core::int;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_implements_getter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_implements_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..60896ad
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_implements_getter.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  get implementedConcreteGetter() → core::int
+    return 0;
+  abstract get implementedAbstractGetter() → core::int;
+  get declaredConcreteImplementsConcreteGetter() → core::int
+    return 0;
+  get declaredAbstractImplementsConcreteGetter() → core::int
+    return 0;
+  abstract get declaredConcreteImplementsAbstractGetter() → core::int;
+  abstract get declaredAbstractImplementsAbstractGetter() → core::int;
+}
+abstract class AbstractClass extends core::Object implements self::Interface {
+  synthetic constructor •() → self::AbstractClass
+    : super core::Object::•()
+    ;
+  get declaredConcreteGetter() → core::int
+    return 0;
+  abstract get declaredAbstractGetter() → core::int;
+  get declaredConcreteImplementsConcreteGetter() → core::int
+    return 0;
+  abstract get declaredAbstractImplementsConcreteGetter() → core::int;
+  get declaredConcreteImplementsAbstractGetter() → core::int
+    return 0;
+  abstract get declaredAbstractImplementsAbstractGetter() → core::int;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_implements_method.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_implements_method.dart.weak.modular.expect
new file mode 100644
index 0000000..fb0c37a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_implements_method.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  method implementedConcreteMethod() → void {}
+  abstract method implementedAbstractMethod() → void;
+  method declaredConcreteImplementsConcreteMethod() → void {}
+  method declaredAbstractImplementsConcreteMethod() → void {}
+  abstract method declaredConcreteImplementsAbstractMethod() → void;
+  abstract method declaredAbstractImplementsAbstractMethod() → void;
+}
+abstract class AbstractClass extends core::Object implements self::Interface {
+  synthetic constructor •() → self::AbstractClass
+    : super core::Object::•()
+    ;
+  method declaredConcreteMethod() → void {}
+  abstract method declaredAbstractMethod() → void;
+  method declaredConcreteImplementsConcreteMethod() → void {}
+  abstract method declaredAbstractImplementsConcreteMethod() → void;
+  method declaredConcreteImplementsAbstractMethod() → void {}
+  abstract method declaredAbstractImplementsAbstractMethod() → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_implements_setter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_implements_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..59931d6
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_implements_setter.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  set implementedConcreteSetter(core::int value) → void {}
+  abstract set implementedAbstractSetter(core::int value) → void;
+  set declaredConcreteImplementsConcreteSetter(core::int value) → void {}
+  set declaredAbstractImplementsConcreteSetter(core::int value) → void {}
+  abstract set declaredConcreteImplementsAbstractSetter(core::int value) → void;
+  abstract set declaredAbstractImplementsAbstractSetter(core::int value) → void;
+}
+abstract class AbstractClass extends core::Object implements self::Interface {
+  synthetic constructor •() → self::AbstractClass
+    : super core::Object::•()
+    ;
+  set declaredConcreteSetter(core::int value) → void {}
+  abstract set declaredAbstractSetter(core::int value) → void;
+  set declaredConcreteImplementsConcreteSetter(core::int value) → void {}
+  abstract set declaredAbstractImplementsConcreteSetter(core::int value) → void;
+  set declaredConcreteImplementsAbstractSetter(core::int value) → void {}
+  abstract set declaredAbstractImplementsAbstractSetter(core::int value) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_mixin.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_mixin.dart.weak.modular.expect
new file mode 100644
index 0000000..a86bf71
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/abstract_mixin.dart.weak.modular.expect
@@ -0,0 +1,54 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  method extendedConcreteMixedInAbstractMethod() → void {}
+  method extendedConcreteMixedInConcreteMethod() → void {}
+  method extendedConcreteMixedInAbstractImplementedMethod(core::int i) → void {}
+  method extendedConcreteMixedInConcreteImplementedMethod(core::int i) → void {}
+}
+class Interface extends core::Object {
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  method extendedConcreteMixedInAbstractImplementedMethod(covariant-by-declaration core::num i) → void {}
+  method extendedConcreteMixedInConcreteImplementedMethod(covariant-by-declaration core::num i) → void {}
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+  abstract method extendedConcreteMixedInAbstractMethod() → void;
+  method extendedConcreteMixedInConcreteMethod() → void {}
+  abstract method extendedConcreteMixedInAbstractImplementedMethod(core::int i) → void;
+  method extendedConcreteMixedInConcreteImplementedMethod(core::int i) → void {}
+}
+class Class = self::Super with self::Mixin implements self::Interface {
+  synthetic constructor •() → self::Class
+    : super self::Super::•()
+    ;
+  abstract mixin-stub method extendedConcreteMixedInAbstractMethod() → void; -> self::Mixin::extendedConcreteMixedInAbstractMethod
+  mixin-super-stub method extendedConcreteMixedInConcreteMethod() → void
+    return super.{self::Mixin::extendedConcreteMixedInConcreteMethod}();
+  forwarding-stub method extendedConcreteMixedInAbstractImplementedMethod(covariant-by-declaration core::int i) → void
+    return super.{self::Super::extendedConcreteMixedInAbstractImplementedMethod}(i);
+  forwarding-stub method extendedConcreteMixedInConcreteImplementedMethod(covariant-by-declaration core::int i) → void
+    return super.{self::Mixin::extendedConcreteMixedInConcreteImplementedMethod}(i);
+}
+class Sub extends self::Class {
+  synthetic constructor •() → self::Sub
+    : super self::Class::•()
+    ;
+  method test() → void {
+    this.{self::Class::extendedConcreteMixedInAbstractMethod}(){() → void};
+    super.{self::Super::extendedConcreteMixedInAbstractMethod}();
+    this.{self::Class::extendedConcreteMixedInConcreteMethod}(){() → void};
+    super.{self::Class::extendedConcreteMixedInConcreteMethod}();
+    this.{self::Class::extendedConcreteMixedInAbstractImplementedMethod}(0){(core::int) → void};
+    super.{self::Class::extendedConcreteMixedInAbstractImplementedMethod}(0);
+    this.{self::Class::extendedConcreteMixedInConcreteImplementedMethod}(0){(core::int) → void};
+    super.{self::Class::extendedConcreteMixedInConcreteImplementedMethod}(0);
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart.weak.modular.expect
new file mode 100644
index 0000000..2697e8e
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart.weak.modular.expect
@@ -0,0 +1,104 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart:5:7: Error: The non-abstract class 'ConcreteSuper' is missing implementations for these members:
+//  - ConcreteSuper.declaredAbstractExtendsAbstractField
+//  - ConcreteSuper.declaredAbstractExtendsAbstractField=
+//  - ConcreteSuper.declaredConcreteExtendsAbstractField
+//  - ConcreteSuper.declaredConcreteExtendsAbstractField=
+//  - ConcreteSuper.extendedAbstractField
+//  - ConcreteSuper.extendedAbstractField=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSuper {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart:16:16: Context: 'ConcreteSuper.declaredAbstractExtendsAbstractField' is defined here.
+//   abstract int declaredAbstractExtendsAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart:16:16: Context: 'ConcreteSuper.declaredAbstractExtendsAbstractField=' is defined here.
+//   abstract int declaredAbstractExtendsAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart:14:16: Context: 'ConcreteSuper.declaredConcreteExtendsAbstractField' is defined here.
+//   abstract int declaredConcreteExtendsAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart:14:16: Context: 'ConcreteSuper.declaredConcreteExtendsAbstractField=' is defined here.
+//   abstract int declaredConcreteExtendsAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart:8:16: Context: 'ConcreteSuper.extendedAbstractField' is defined here.
+//   abstract int extendedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart:8:16: Context: 'ConcreteSuper.extendedAbstractField=' is defined here.
+//   abstract int extendedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart:19:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - ConcreteClass.declaredAbstractExtendsAbstractField
+//  - ConcreteClass.declaredAbstractExtendsAbstractField=
+//  - ConcreteClass.declaredAbstractField
+//  - ConcreteClass.declaredAbstractField=
+//  - ConcreteSuper.extendedAbstractField
+//  - ConcreteSuper.extendedAbstractField=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass extends ConcreteSuper {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart:30:16: Context: 'ConcreteClass.declaredAbstractExtendsAbstractField' is defined here.
+//   abstract int declaredAbstractExtendsAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart:30:16: Context: 'ConcreteClass.declaredAbstractExtendsAbstractField=' is defined here.
+//   abstract int declaredAbstractExtendsAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart:22:16: Context: 'ConcreteClass.declaredAbstractField' is defined here.
+//   abstract int declaredAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart:22:16: Context: 'ConcreteClass.declaredAbstractField=' is defined here.
+//   abstract int declaredAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart:8:16: Context: 'ConcreteSuper.extendedAbstractField' is defined here.
+//   abstract int extendedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_field.dart:8:16: Context: 'ConcreteSuper.extendedAbstractField=' is defined here.
+//   abstract int extendedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class ConcreteSuper extends core::Object {
+  field core::int extendedConcreteField = 0;
+  field core::int declaredConcreteExtendsConcreteField = 0;
+  field core::int declaredAbstractExtendsConcreteField = 0;
+  synthetic constructor •() → self::ConcreteSuper
+    : super core::Object::•()
+    ;
+  abstract get extendedAbstractField() → core::int;
+  abstract set extendedAbstractField(core::int #externalFieldValue) → void;
+  abstract get declaredConcreteExtendsAbstractField() → core::int;
+  abstract set declaredConcreteExtendsAbstractField(core::int #externalFieldValue) → void;
+  abstract get declaredAbstractExtendsAbstractField() → core::int;
+  abstract set declaredAbstractExtendsAbstractField(core::int #externalFieldValue) → void;
+}
+class ConcreteClass extends self::ConcreteSuper {
+  field core::int declaredConcreteField = 0;
+  field core::int declaredConcreteExtendsConcreteField = 0;
+  field core::int declaredConcreteExtendsAbstractField = 0;
+  synthetic constructor •() → self::ConcreteClass
+    : super self::ConcreteSuper::•()
+    ;
+  abstract get declaredAbstractField() → core::int;
+  abstract set declaredAbstractField(core::int #externalFieldValue) → void;
+  abstract get declaredAbstractExtendsConcreteField() → core::int;
+  abstract set declaredAbstractExtendsConcreteField(core::int #externalFieldValue) → void;
+  abstract get declaredAbstractExtendsAbstractField() → core::int;
+  abstract set declaredAbstractExtendsAbstractField(core::int #externalFieldValue) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_final_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_final_field.dart.weak.modular.expect
new file mode 100644
index 0000000..4b81a56
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_final_field.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_final_field.dart:5:7: Error: The non-abstract class 'ConcreteSuper' is missing implementations for these members:
+//  - ConcreteSuper.declaredAbstractExtendsAbstractField
+//  - ConcreteSuper.declaredConcreteExtendsAbstractField
+//  - ConcreteSuper.extendedAbstractField
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSuper {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_final_field.dart:16:22: Context: 'ConcreteSuper.declaredAbstractExtendsAbstractField' is defined here.
+//   abstract final int declaredAbstractExtendsAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_final_field.dart:14:22: Context: 'ConcreteSuper.declaredConcreteExtendsAbstractField' is defined here.
+//   abstract final int declaredConcreteExtendsAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_final_field.dart:8:22: Context: 'ConcreteSuper.extendedAbstractField' is defined here.
+//   abstract final int extendedAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_final_field.dart:19:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - ConcreteClass.declaredAbstractExtendsAbstractField
+//  - ConcreteClass.declaredAbstractField
+//  - ConcreteSuper.extendedAbstractField
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass extends ConcreteSuper {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_final_field.dart:30:22: Context: 'ConcreteClass.declaredAbstractExtendsAbstractField' is defined here.
+//   abstract final int declaredAbstractExtendsAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_final_field.dart:22:22: Context: 'ConcreteClass.declaredAbstractField' is defined here.
+//   abstract final int declaredAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_final_field.dart:8:22: Context: 'ConcreteSuper.extendedAbstractField' is defined here.
+//   abstract final int extendedAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class ConcreteSuper extends core::Object {
+  final field core::int extendedConcreteField = 0;
+  final field core::int declaredConcreteExtendsConcreteField = 0;
+  final field core::int declaredAbstractExtendsConcreteField = 0;
+  synthetic constructor •() → self::ConcreteSuper
+    : super core::Object::•()
+    ;
+  abstract get extendedAbstractField() → core::int;
+  abstract get declaredConcreteExtendsAbstractField() → core::int;
+  abstract get declaredAbstractExtendsAbstractField() → core::int;
+}
+class ConcreteClass extends self::ConcreteSuper {
+  final field core::int declaredConcreteField = 0;
+  final field core::int declaredConcreteExtendsConcreteField = 0;
+  final field core::int declaredConcreteExtendsAbstractField = 0;
+  synthetic constructor •() → self::ConcreteClass
+    : super self::ConcreteSuper::•()
+    ;
+  abstract get declaredAbstractField() → core::int;
+  abstract get declaredAbstractExtendsConcreteField() → core::int;
+  abstract get declaredAbstractExtendsAbstractField() → core::int;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_getter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..626d8af
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_getter.dart.weak.modular.expect
@@ -0,0 +1,80 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_getter.dart:5:7: Error: The non-abstract class 'ConcreteSuper' is missing implementations for these members:
+//  - ConcreteSuper.declaredAbstractExtendsAbstractGetter
+//  - ConcreteSuper.declaredConcreteExtendsAbstractGetter
+//  - ConcreteSuper.extendedAbstractGetter
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSuper {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_getter.dart:16:11: Context: 'ConcreteSuper.declaredAbstractExtendsAbstractGetter' is defined here.
+//   int get declaredAbstractExtendsAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_getter.dart:14:11: Context: 'ConcreteSuper.declaredConcreteExtendsAbstractGetter' is defined here.
+//   int get declaredConcreteExtendsAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_getter.dart:8:11: Context: 'ConcreteSuper.extendedAbstractGetter' is defined here.
+//   int get extendedAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_getter.dart:19:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - ConcreteClass.declaredAbstractExtendsAbstractGetter
+//  - ConcreteClass.declaredAbstractGetter
+//  - ConcreteSuper.extendedAbstractGetter
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass extends ConcreteSuper {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_getter.dart:30:11: Context: 'ConcreteClass.declaredAbstractExtendsAbstractGetter' is defined here.
+//   int get declaredAbstractExtendsAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_getter.dart:22:11: Context: 'ConcreteClass.declaredAbstractGetter' is defined here.
+//   int get declaredAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_getter.dart:8:11: Context: 'ConcreteSuper.extendedAbstractGetter' is defined here.
+//   int get extendedAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class ConcreteSuper extends core::Object {
+  synthetic constructor •() → self::ConcreteSuper
+    : super core::Object::•()
+    ;
+  get extendedConcreteGetter() → core::int
+    return 0;
+  abstract get extendedAbstractGetter() → core::int;
+  get declaredConcreteExtendsConcreteGetter() → core::int
+    return 0;
+  get declaredAbstractExtendsConcreteGetter() → core::int
+    return 0;
+  abstract get declaredConcreteExtendsAbstractGetter() → core::int;
+  abstract get declaredAbstractExtendsAbstractGetter() → core::int;
+}
+class ConcreteClass extends self::ConcreteSuper {
+  synthetic constructor •() → self::ConcreteClass
+    : super self::ConcreteSuper::•()
+    ;
+  get declaredConcreteGetter() → core::int
+    return 0;
+  abstract get declaredAbstractGetter() → core::int;
+  get declaredConcreteExtendsConcreteGetter() → core::int
+    return 0;
+  abstract get declaredAbstractExtendsConcreteGetter() → core::int;
+  get declaredConcreteExtendsAbstractGetter() → core::int
+    return 0;
+  abstract get declaredAbstractExtendsAbstractGetter() → core::int;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_method.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_method.dart.weak.modular.expect
new file mode 100644
index 0000000..0eba0b9
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_method.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_method.dart:5:7: Error: The non-abstract class 'ConcreteSuper' is missing implementations for these members:
+//  - ConcreteSuper.declaredAbstractExtendsAbstractMethod
+//  - ConcreteSuper.declaredConcreteExtendsAbstractMethod
+//  - ConcreteSuper.extendedAbstractMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSuper {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_method.dart:16:8: Context: 'ConcreteSuper.declaredAbstractExtendsAbstractMethod' is defined here.
+//   void declaredAbstractExtendsAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_method.dart:14:8: Context: 'ConcreteSuper.declaredConcreteExtendsAbstractMethod' is defined here.
+//   void declaredConcreteExtendsAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_method.dart:8:8: Context: 'ConcreteSuper.extendedAbstractMethod' is defined here.
+//   void extendedAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_method.dart:19:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - ConcreteClass.declaredAbstractExtendsAbstractMethod
+//  - ConcreteClass.declaredAbstractMethod
+//  - ConcreteSuper.extendedAbstractMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass extends ConcreteSuper {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_method.dart:30:8: Context: 'ConcreteClass.declaredAbstractExtendsAbstractMethod' is defined here.
+//   void declaredAbstractExtendsAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_method.dart:22:8: Context: 'ConcreteClass.declaredAbstractMethod' is defined here.
+//   void declaredAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_method.dart:8:8: Context: 'ConcreteSuper.extendedAbstractMethod' is defined here.
+//   void extendedAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class ConcreteSuper extends core::Object {
+  synthetic constructor •() → self::ConcreteSuper
+    : super core::Object::•()
+    ;
+  method extendedConcreteMethod() → void {}
+  abstract method extendedAbstractMethod() → void;
+  method declaredConcreteExtendsConcreteMethod() → void {}
+  method declaredAbstractExtendsConcreteMethod() → void {}
+  abstract method declaredConcreteExtendsAbstractMethod() → void;
+  abstract method declaredAbstractExtendsAbstractMethod() → void;
+}
+class ConcreteClass extends self::ConcreteSuper {
+  synthetic constructor •() → self::ConcreteClass
+    : super self::ConcreteSuper::•()
+    ;
+  method declaredConcreteMethod() → void {}
+  abstract method declaredAbstractMethod() → void;
+  method declaredConcreteExtendsConcreteMethod() → void {}
+  abstract method declaredAbstractExtendsConcreteMethod() → void;
+  method declaredConcreteExtendsAbstractMethod() → void {}
+  abstract method declaredAbstractExtendsAbstractMethod() → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_setter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..2df220c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_setter.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_setter.dart:5:7: Error: The non-abstract class 'ConcreteSuper' is missing implementations for these members:
+//  - ConcreteSuper.declaredAbstractExtendsAbstractSetter=
+//  - ConcreteSuper.declaredConcreteExtendsAbstractSetter=
+//  - ConcreteSuper.extendedAbstractSetter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSuper {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_setter.dart:16:12: Context: 'ConcreteSuper.declaredAbstractExtendsAbstractSetter=' is defined here.
+//   void set declaredAbstractExtendsAbstractSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_setter.dart:14:12: Context: 'ConcreteSuper.declaredConcreteExtendsAbstractSetter=' is defined here.
+//   void set declaredConcreteExtendsAbstractSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_setter.dart:8:12: Context: 'ConcreteSuper.extendedAbstractSetter=' is defined here.
+//   void set extendedAbstractSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_setter.dart:19:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - ConcreteClass.declaredAbstractExtendsAbstractSetter=
+//  - ConcreteClass.declaredAbstractSetter=
+//  - ConcreteSuper.extendedAbstractSetter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass extends ConcreteSuper {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_setter.dart:30:12: Context: 'ConcreteClass.declaredAbstractExtendsAbstractSetter=' is defined here.
+//   void set declaredAbstractExtendsAbstractSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_setter.dart:22:12: Context: 'ConcreteClass.declaredAbstractSetter=' is defined here.
+//   void set declaredAbstractSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_extends_setter.dart:8:12: Context: 'ConcreteSuper.extendedAbstractSetter=' is defined here.
+//   void set extendedAbstractSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class ConcreteSuper extends core::Object {
+  synthetic constructor •() → self::ConcreteSuper
+    : super core::Object::•()
+    ;
+  set extendedConcreteSetter(core::int value) → void {}
+  abstract set extendedAbstractSetter(core::int value) → void;
+  set declaredConcreteExtendsConcreteSetter(core::int value) → void {}
+  set declaredAbstractExtendsConcreteSetter(core::int value) → void {}
+  abstract set declaredConcreteExtendsAbstractSetter(core::int value) → void;
+  abstract set declaredAbstractExtendsAbstractSetter(core::int value) → void;
+}
+class ConcreteClass extends self::ConcreteSuper {
+  synthetic constructor •() → self::ConcreteClass
+    : super self::ConcreteSuper::•()
+    ;
+  set declaredConcreteSetter(core::int value) → void {}
+  abstract set declaredAbstractSetter(core::int value) → void;
+  set declaredConcreteExtendsConcreteSetter(core::int value) → void {}
+  abstract set declaredAbstractExtendsConcreteSetter(core::int value) → void;
+  set declaredConcreteExtendsAbstractSetter(core::int value) → void {}
+  abstract set declaredAbstractExtendsAbstractSetter(core::int value) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart.weak.modular.expect
new file mode 100644
index 0000000..3c9afcd
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart.weak.modular.expect
@@ -0,0 +1,116 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:5:7: Error: The non-abstract class 'Interface' is missing implementations for these members:
+//  - Interface.declaredAbstractImplementsAbstractField
+//  - Interface.declaredAbstractImplementsAbstractField=
+//  - Interface.declaredConcreteImplementsAbstractField
+//  - Interface.declaredConcreteImplementsAbstractField=
+//  - Interface.implementedAbstractField
+//  - Interface.implementedAbstractField=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Interface {
+//       ^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:16:16: Context: 'Interface.declaredAbstractImplementsAbstractField' is defined here.
+//   abstract int declaredAbstractImplementsAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:16:16: Context: 'Interface.declaredAbstractImplementsAbstractField=' is defined here.
+//   abstract int declaredAbstractImplementsAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:14:16: Context: 'Interface.declaredConcreteImplementsAbstractField' is defined here.
+//   abstract int declaredConcreteImplementsAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:14:16: Context: 'Interface.declaredConcreteImplementsAbstractField=' is defined here.
+//   abstract int declaredConcreteImplementsAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:8:16: Context: 'Interface.implementedAbstractField' is defined here.
+//   abstract int implementedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:8:16: Context: 'Interface.implementedAbstractField=' is defined here.
+//   abstract int implementedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:19:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - ConcreteClass.declaredAbstractField
+//  - ConcreteClass.declaredAbstractField=
+//  - ConcreteClass.declaredAbstractImplementsAbstractField
+//  - ConcreteClass.declaredAbstractImplementsAbstractField=
+//  - ConcreteClass.declaredAbstractImplementsConcreteField
+//  - ConcreteClass.declaredAbstractImplementsConcreteField=
+//  - Interface.implementedAbstractField
+//  - Interface.implementedAbstractField=
+//  - Interface.implementedConcreteField
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass implements Interface {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:22:16: Context: 'ConcreteClass.declaredAbstractField' is defined here.
+//   abstract int declaredAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:22:16: Context: 'ConcreteClass.declaredAbstractField=' is defined here.
+//   abstract int declaredAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:30:16: Context: 'ConcreteClass.declaredAbstractImplementsAbstractField' is defined here.
+//   abstract int declaredAbstractImplementsAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:30:16: Context: 'ConcreteClass.declaredAbstractImplementsAbstractField=' is defined here.
+//   abstract int declaredAbstractImplementsAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:26:16: Context: 'ConcreteClass.declaredAbstractImplementsConcreteField' is defined here.
+//   abstract int declaredAbstractImplementsConcreteField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:26:16: Context: 'ConcreteClass.declaredAbstractImplementsConcreteField=' is defined here.
+//   abstract int declaredAbstractImplementsConcreteField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:8:16: Context: 'Interface.implementedAbstractField' is defined here.
+//   abstract int implementedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:8:16: Context: 'Interface.implementedAbstractField=' is defined here.
+//   abstract int implementedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_field.dart:6:7: Context: 'Interface.implementedConcreteField' is defined here.
+//   int implementedConcreteField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Interface extends core::Object {
+  field core::int implementedConcreteField = 0;
+  field core::int declaredConcreteImplementsConcreteField = 0;
+  field core::int declaredAbstractImplementsConcreteField = 0;
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  abstract get implementedAbstractField() → core::int;
+  abstract set implementedAbstractField(core::int #externalFieldValue) → void;
+  abstract get declaredConcreteImplementsAbstractField() → core::int;
+  abstract set declaredConcreteImplementsAbstractField(core::int #externalFieldValue) → void;
+  abstract get declaredAbstractImplementsAbstractField() → core::int;
+  abstract set declaredAbstractImplementsAbstractField(core::int #externalFieldValue) → void;
+}
+class ConcreteClass extends core::Object implements self::Interface {
+  field core::int declaredConcreteField = 0;
+  field core::int declaredConcreteImplementsConcreteField = 0;
+  field core::int declaredConcreteImplementsAbstractField = 0;
+  synthetic constructor •() → self::ConcreteClass
+    : super core::Object::•()
+    ;
+  abstract get declaredAbstractField() → core::int;
+  abstract set declaredAbstractField(core::int #externalFieldValue) → void;
+  abstract get declaredAbstractImplementsConcreteField() → core::int;
+  abstract set declaredAbstractImplementsConcreteField(core::int #externalFieldValue) → void;
+  abstract get declaredAbstractImplementsAbstractField() → core::int;
+  abstract set declaredAbstractImplementsAbstractField(core::int #externalFieldValue) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_final_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_final_field.dart.weak.modular.expect
new file mode 100644
index 0000000..921aaec
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_final_field.dart.weak.modular.expect
@@ -0,0 +1,82 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_final_field.dart:5:7: Error: The non-abstract class 'Interface' is missing implementations for these members:
+//  - Interface.declaredAbstractImplementsAbstractField
+//  - Interface.declaredConcreteImplementsAbstractField
+//  - Interface.implementedAbstractField
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Interface {
+//       ^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_final_field.dart:16:22: Context: 'Interface.declaredAbstractImplementsAbstractField' is defined here.
+//   abstract final int declaredAbstractImplementsAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_final_field.dart:14:22: Context: 'Interface.declaredConcreteImplementsAbstractField' is defined here.
+//   abstract final int declaredConcreteImplementsAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_final_field.dart:8:22: Context: 'Interface.implementedAbstractField' is defined here.
+//   abstract final int implementedAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_final_field.dart:19:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - ConcreteClass.declaredAbstractField
+//  - ConcreteClass.declaredAbstractImplementsAbstractField
+//  - ConcreteClass.declaredAbstractImplementsConcreteField
+//  - Interface.implementedAbstractField
+//  - Interface.implementedConcreteField
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass implements Interface {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_final_field.dart:22:22: Context: 'ConcreteClass.declaredAbstractField' is defined here.
+//   abstract final int declaredAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_final_field.dart:30:22: Context: 'ConcreteClass.declaredAbstractImplementsAbstractField' is defined here.
+//   abstract final int declaredAbstractImplementsAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_final_field.dart:26:22: Context: 'ConcreteClass.declaredAbstractImplementsConcreteField' is defined here.
+//   abstract final int declaredAbstractImplementsConcreteField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_final_field.dart:8:22: Context: 'Interface.implementedAbstractField' is defined here.
+//   abstract final int implementedAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_final_field.dart:6:13: Context: 'Interface.implementedConcreteField' is defined here.
+//   final int implementedConcreteField = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Interface extends core::Object {
+  final field core::int implementedConcreteField = 0;
+  final field core::int declaredConcreteImplementsConcreteField = 0;
+  final field core::int declaredAbstractImplementsConcreteField = 0;
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  abstract get implementedAbstractField() → core::int;
+  abstract get declaredConcreteImplementsAbstractField() → core::int;
+  abstract get declaredAbstractImplementsAbstractField() → core::int;
+}
+class ConcreteClass extends core::Object implements self::Interface {
+  final field core::int declaredConcreteField = 0;
+  final field core::int declaredConcreteImplementsConcreteField = 0;
+  final field core::int declaredConcreteImplementsAbstractField = 0;
+  synthetic constructor •() → self::ConcreteClass
+    : super core::Object::•()
+    ;
+  abstract get declaredAbstractField() → core::int;
+  abstract get declaredAbstractImplementsConcreteField() → core::int;
+  abstract get declaredAbstractImplementsAbstractField() → core::int;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_getter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..5c3ce45
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_getter.dart.weak.modular.expect
@@ -0,0 +1,88 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_getter.dart:5:7: Error: The non-abstract class 'Interface' is missing implementations for these members:
+//  - Interface.declaredAbstractImplementsAbstractGetter
+//  - Interface.declaredConcreteImplementsAbstractGetter
+//  - Interface.implementedAbstractGetter
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Interface {
+//       ^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_getter.dart:16:11: Context: 'Interface.declaredAbstractImplementsAbstractGetter' is defined here.
+//   int get declaredAbstractImplementsAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_getter.dart:14:11: Context: 'Interface.declaredConcreteImplementsAbstractGetter' is defined here.
+//   int get declaredConcreteImplementsAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_getter.dart:8:11: Context: 'Interface.implementedAbstractGetter' is defined here.
+//   int get implementedAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_getter.dart:19:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - ConcreteClass.declaredAbstractGetter
+//  - ConcreteClass.declaredAbstractImplementsAbstractGetter
+//  - ConcreteClass.declaredAbstractImplementsConcreteGetter
+//  - Interface.implementedAbstractGetter
+//  - Interface.implementedConcreteGetter
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass implements Interface {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_getter.dart:22:11: Context: 'ConcreteClass.declaredAbstractGetter' is defined here.
+//   int get declaredAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_getter.dart:30:11: Context: 'ConcreteClass.declaredAbstractImplementsAbstractGetter' is defined here.
+//   int get declaredAbstractImplementsAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_getter.dart:26:11: Context: 'ConcreteClass.declaredAbstractImplementsConcreteGetter' is defined here.
+//   int get declaredAbstractImplementsConcreteGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_getter.dart:8:11: Context: 'Interface.implementedAbstractGetter' is defined here.
+//   int get implementedAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_getter.dart:6:11: Context: 'Interface.implementedConcreteGetter' is defined here.
+//   int get implementedConcreteGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Interface extends core::Object {
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  get implementedConcreteGetter() → core::int
+    return 0;
+  abstract get implementedAbstractGetter() → core::int;
+  get declaredConcreteImplementsConcreteGetter() → core::int
+    return 0;
+  get declaredAbstractImplementsConcreteGetter() → core::int
+    return 0;
+  abstract get declaredConcreteImplementsAbstractGetter() → core::int;
+  abstract get declaredAbstractImplementsAbstractGetter() → core::int;
+}
+class ConcreteClass extends core::Object implements self::Interface {
+  synthetic constructor •() → self::ConcreteClass
+    : super core::Object::•()
+    ;
+  get declaredConcreteGetter() → core::int
+    return 0;
+  abstract get declaredAbstractGetter() → core::int;
+  get declaredConcreteImplementsConcreteGetter() → core::int
+    return 0;
+  abstract get declaredAbstractImplementsConcreteGetter() → core::int;
+  get declaredConcreteImplementsAbstractGetter() → core::int
+    return 0;
+  abstract get declaredAbstractImplementsAbstractGetter() → core::int;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_method.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_method.dart.weak.modular.expect
new file mode 100644
index 0000000..ff9e0ea
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_method.dart.weak.modular.expect
@@ -0,0 +1,82 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_method.dart:5:7: Error: The non-abstract class 'Interface' is missing implementations for these members:
+//  - Interface.declaredAbstractImplementsAbstractMethod
+//  - Interface.declaredConcreteImplementsAbstractMethod
+//  - Interface.implementedAbstractMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Interface {
+//       ^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_method.dart:16:8: Context: 'Interface.declaredAbstractImplementsAbstractMethod' is defined here.
+//   void declaredAbstractImplementsAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_method.dart:14:8: Context: 'Interface.declaredConcreteImplementsAbstractMethod' is defined here.
+//   void declaredConcreteImplementsAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_method.dart:8:8: Context: 'Interface.implementedAbstractMethod' is defined here.
+//   void implementedAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_method.dart:19:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - ConcreteClass.declaredAbstractImplementsAbstractMethod
+//  - ConcreteClass.declaredAbstractImplementsConcreteMethod
+//  - ConcreteClass.declaredAbstractMethod
+//  - Interface.implementedAbstractMethod
+//  - Interface.implementedConcreteMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass implements Interface {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_method.dart:30:8: Context: 'ConcreteClass.declaredAbstractImplementsAbstractMethod' is defined here.
+//   void declaredAbstractImplementsAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_method.dart:26:8: Context: 'ConcreteClass.declaredAbstractImplementsConcreteMethod' is defined here.
+//   void declaredAbstractImplementsConcreteMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_method.dart:22:8: Context: 'ConcreteClass.declaredAbstractMethod' is defined here.
+//   void declaredAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_method.dart:8:8: Context: 'Interface.implementedAbstractMethod' is defined here.
+//   void implementedAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_method.dart:6:8: Context: 'Interface.implementedConcreteMethod' is defined here.
+//   void implementedConcreteMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Interface extends core::Object {
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  method implementedConcreteMethod() → void {}
+  abstract method implementedAbstractMethod() → void;
+  method declaredConcreteImplementsConcreteMethod() → void {}
+  method declaredAbstractImplementsConcreteMethod() → void {}
+  abstract method declaredConcreteImplementsAbstractMethod() → void;
+  abstract method declaredAbstractImplementsAbstractMethod() → void;
+}
+class ConcreteClass extends core::Object implements self::Interface {
+  synthetic constructor •() → self::ConcreteClass
+    : super core::Object::•()
+    ;
+  method declaredConcreteMethod() → void {}
+  abstract method declaredAbstractMethod() → void;
+  method declaredConcreteImplementsConcreteMethod() → void {}
+  abstract method declaredAbstractImplementsConcreteMethod() → void;
+  method declaredConcreteImplementsAbstractMethod() → void {}
+  abstract method declaredAbstractImplementsAbstractMethod() → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_setter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..ca9b49b
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_setter.dart.weak.modular.expect
@@ -0,0 +1,82 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_setter.dart:5:7: Error: The non-abstract class 'Interface' is missing implementations for these members:
+//  - Interface.declaredAbstractImplementsAbstractSetter=
+//  - Interface.declaredConcreteImplementsAbstractSetter=
+//  - Interface.implementedAbstractSetter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Interface {
+//       ^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_setter.dart:16:12: Context: 'Interface.declaredAbstractImplementsAbstractSetter=' is defined here.
+//   void set declaredAbstractImplementsAbstractSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_setter.dart:14:12: Context: 'Interface.declaredConcreteImplementsAbstractSetter=' is defined here.
+//   void set declaredConcreteImplementsAbstractSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_setter.dart:8:12: Context: 'Interface.implementedAbstractSetter=' is defined here.
+//   void set implementedAbstractSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_setter.dart:19:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - ConcreteClass.declaredAbstractImplementsAbstractSetter=
+//  - ConcreteClass.declaredAbstractImplementsConcreteSetter=
+//  - ConcreteClass.declaredAbstractSetter=
+//  - Interface.implementedAbstractSetter=
+//  - Interface.implementedConcreteSetter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass implements Interface {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_setter.dart:30:12: Context: 'ConcreteClass.declaredAbstractImplementsAbstractSetter=' is defined here.
+//   void set declaredAbstractImplementsAbstractSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_setter.dart:26:12: Context: 'ConcreteClass.declaredAbstractImplementsConcreteSetter=' is defined here.
+//   void set declaredAbstractImplementsConcreteSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_setter.dart:22:12: Context: 'ConcreteClass.declaredAbstractSetter=' is defined here.
+//   void set declaredAbstractSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_setter.dart:8:12: Context: 'Interface.implementedAbstractSetter=' is defined here.
+//   void set implementedAbstractSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/concrete_implements_setter.dart:6:12: Context: 'Interface.implementedConcreteSetter=' is defined here.
+//   void set implementedConcreteSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Interface extends core::Object {
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  set implementedConcreteSetter(core::int value) → void {}
+  abstract set implementedAbstractSetter(core::int value) → void;
+  set declaredConcreteImplementsConcreteSetter(core::int value) → void {}
+  set declaredAbstractImplementsConcreteSetter(core::int value) → void {}
+  abstract set declaredConcreteImplementsAbstractSetter(core::int value) → void;
+  abstract set declaredAbstractImplementsAbstractSetter(core::int value) → void;
+}
+class ConcreteClass extends core::Object implements self::Interface {
+  synthetic constructor •() → self::ConcreteClass
+    : super core::Object::•()
+    ;
+  set declaredConcreteSetter(core::int value) → void {}
+  abstract set declaredAbstractSetter(core::int value) → void;
+  set declaredConcreteImplementsConcreteSetter(core::int value) → void {}
+  abstract set declaredAbstractImplementsConcreteSetter(core::int value) → void;
+  set declaredConcreteImplementsAbstractSetter(core::int value) → void {}
+  abstract set declaredAbstractImplementsAbstractSetter(core::int value) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart.weak.modular.expect
new file mode 100644
index 0000000..f1538ce
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart.weak.modular.expect
@@ -0,0 +1,323 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:90:16: Error: Can't inherit members that conflict with each other.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:13:8: Context: This is one inherited member.
+//   void extendedMethodMixedInGetter() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:43:11: Context: This is the other inherited member.
+//   int get extendedMethodMixedInGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:93:11: Error: Can't declare a member that conflicts with an inherited one.
+//   int get extendedMethodDeclaredGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:6:8: Context: This is the inherited member.
+//   void extendedMethodDeclaredGetter() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:95:7: Error: Can't declare a member that conflicts with an inherited one.
+//   int extendedMethodDeclaredField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:8:8: Context: This is the inherited member.
+//   void extendedMethodDeclaredField() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:96:8: Error: Can't declare a member that conflicts with an inherited one.
+//   void extendedGetterDeclaredMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:9:11: Context: This is the inherited member.
+//   int get extendedGetterDeclaredMethod => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:97:8: Error: Can't declare a member that conflicts with an inherited one.
+//   void extendedSetterDeclaredMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:10:12: Context: This is the inherited member.
+//   void set extendedSetterDeclaredMethod(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:98:8: Error: Can't declare a member that conflicts with an inherited one.
+//   void extendedFieldDeclaredMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:11:7: Context: This is the inherited member.
+//   int extendedFieldDeclaredMethod = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:100:11: Error: Can't declare a member that conflicts with an inherited one.
+//   int get mixedInMethodDeclaredGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:29:8: Context: This is the inherited member.
+//   void mixedInMethodDeclaredGetter() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:102:7: Error: Can't declare a member that conflicts with an inherited one.
+//   int mixedInMethodDeclaredField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:31:8: Context: This is the inherited member.
+//   void mixedInMethodDeclaredField() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:103:8: Error: Can't declare a member that conflicts with an inherited one.
+//   void mixedInGetterDeclaredMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:32:11: Context: This is the inherited member.
+//   int get mixedInGetterDeclaredMethod => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:104:8: Error: Can't declare a member that conflicts with an inherited one.
+//   void mixedInSetterDeclaredMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:33:12: Context: This is the inherited member.
+//   void set mixedInSetterDeclaredMethod(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:105:8: Error: Can't declare a member that conflicts with an inherited one.
+//   void mixedInFieldDeclaredMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:34:7: Context: This is the inherited member.
+//   int mixedInFieldDeclaredMethod = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:107:11: Error: Can't declare a member that conflicts with an inherited one.
+//   int get implementedMethodDeclaredGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:52:8: Context: This is the inherited member.
+//   void implementedMethodDeclaredGetter() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:109:7: Error: Can't declare a member that conflicts with an inherited one.
+//   int implementedMethodDeclaredField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:54:8: Context: This is the inherited member.
+//   void implementedMethodDeclaredField() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:110:8: Error: Can't declare a member that conflicts with an inherited one.
+//   void implementedGetterDeclaredMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:55:11: Context: This is the inherited member.
+//   int get implementedGetterDeclaredMethod => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:111:8: Error: Can't declare a member that conflicts with an inherited one.
+//   void implementedSetterDeclaredMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:56:12: Context: This is the inherited member.
+//   void set implementedSetterDeclaredMethod(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:112:8: Error: Can't declare a member that conflicts with an inherited one.
+//   void implementedFieldDeclaredMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:57:7: Context: This is the inherited member.
+//   int implementedFieldDeclaredMethod = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:115:12: Error: 'declaredMethodAndSetter' is already declared in this scope.
+//   void set declaredMethodAndSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:114:8: Context: Previous declaration of 'declaredMethodAndSetter'.
+//   void declaredMethodAndSetter() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:94:12: Error: Can't declare a member that conflicts with an inherited one.
+//   void set extendedMethodDeclaredSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:7:8: Context: This is the inherited member.
+//   void extendedMethodDeclaredSetter() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:101:12: Error: Can't declare a member that conflicts with an inherited one.
+//   void set mixedInMethodDeclaredSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:30:8: Context: This is the inherited member.
+//   void mixedInMethodDeclaredSetter() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:108:12: Error: Can't declare a member that conflicts with an inherited one.
+//   void set implementedMethodDeclaredSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/conflict.dart:53:8: Context: This is the inherited member.
+//   void implementedMethodDeclaredSetter() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  field core::int extendedFieldDeclaredMethod = 0;
+  field core::int extendedFieldMixedInMethod = 0;
+  field core::int extendedFieldImplementedMethod = 0;
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  method extendedMethodDeclaredGetter() → void {}
+  method extendedMethodDeclaredSetter() → void {}
+  method extendedMethodDeclaredField() → void {}
+  get extendedGetterDeclaredMethod() → core::int
+    return 0;
+  set extendedSetterDeclaredMethod(core::int value) → void {}
+  method extendedMethodMixedInGetter() → void {}
+  method extendedMethodMixedInSetter() → void {}
+  method extendedMethodMixedInField() → void {}
+  get extendedGetterMixedInMethod() → core::int
+    return 0;
+  set extendedSetterMixedInMethod(core::int value) → void {}
+  method extendedMethodImplementedGetter() → void {}
+  method extendedMethodImplementedSetter() → void {}
+  method extendedMethodImplementedField() → void {}
+  get extendedGetterImplementedMethod() → core::int
+    return 0;
+  set extendedSetterImplementedMethod(core::int value) → void {}
+}
+class Mixin extends core::Object {
+  field core::int mixedInFieldDeclaredMethod = 0;
+  field core::int mixedInFieldImplementedMethod = 0;
+  field core::int extendedMethodMixedInField = 0;
+  synthetic constructor •() → self::Mixin
+    : super core::Object::•()
+    ;
+  method mixedInMethodDeclaredGetter() → void {}
+  method mixedInMethodDeclaredSetter() → void {}
+  method mixedInMethodDeclaredField() → void {}
+  get mixedInGetterDeclaredMethod() → core::int
+    return 0;
+  set mixedInSetterDeclaredMethod(core::int value) → void {}
+  method mixedInMethodImplementedGetter() → void {}
+  method mixedInMethodImplementedSetter() → void {}
+  method mixedInMethodImplementedField() → void {}
+  get mixedInGetterImplementedMethod() → core::int
+    return 0;
+  set mixedInSetterImplementedMethod(core::int value) → void {}
+  get extendedMethodMixedInGetter() → core::int
+    return 0;
+  set extendedMethodMixedInSetter(core::int value) → void {}
+  method extendedGetterMixedInMethod() → void {}
+  method extendedSetterMixedInMethod() → void {}
+  method extendedFieldMixedInMethod() → void {}
+}
+class Interface1 extends core::Object {
+  field core::int implementedFieldDeclaredMethod = 0;
+  field core::int implementedFieldImplementedMethod = 0;
+  field core::int extendedMethodImplementedField = 0;
+  field core::int mixedInMethodImplementedField = 0;
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+  method implementedMethodDeclaredGetter() → void {}
+  method implementedMethodDeclaredSetter() → void {}
+  method implementedMethodDeclaredField() → void {}
+  get implementedGetterDeclaredMethod() → core::int
+    return 0;
+  set implementedSetterDeclaredMethod(core::int value) → void {}
+  method implementedMethodImplementedGetter() → void {}
+  method implementedMethodImplementedSetter() → void {}
+  method implementedMethodImplementedField() → void {}
+  get implementedGetterImplementedMethod() → core::int
+    return 0;
+  set implementedSetterImplementedMethod(core::int value) → void {}
+  get extendedMethodImplementedGetter() → core::int
+    return 0;
+  set extendedMethodImplementedSetter(core::int value) → void {}
+  method extendedGetterImplementedMethod() → void {}
+  method extendedSetterImplementedMethod() → void {}
+  method extendedFieldImplementedMethod() → void {}
+  get mixedInMethodImplementedGetter() → core::int
+    return 0;
+  set mixedInMethodImplementedSetter(core::int value) → void {}
+  method mixedInGetterImplementedMethod() → void {}
+  method mixedInSetterImplementedMethod() → void {}
+  method mixedInFieldImplementedMethod() → void {}
+}
+class Interface2 extends core::Object {
+  field core::int implementedMethodImplementedField = 0;
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+  get implementedMethodImplementedGetter() → core::int
+    return 0;
+  set implementedMethodImplementedSetter(core::int value) → void {}
+  method implementedGetterImplementedMethod() → void {}
+  method implementedSetterImplementedMethod() → void {}
+  method implementedFieldImplementedMethod() → void {}
+}
+abstract class _Class&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&Mixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub method mixedInMethodDeclaredSetter() → void
+    return super.{self::Mixin::mixedInMethodDeclaredSetter}();
+  mixin-super-stub get mixedInFieldDeclaredMethod() → core::int
+    return super.{self::Mixin::mixedInFieldDeclaredMethod};
+  mixin-super-stub set mixedInFieldDeclaredMethod(core::int value) → void
+    return super.{self::Mixin::mixedInFieldDeclaredMethod} = value;
+  mixin-super-stub get mixedInFieldImplementedMethod() → core::int
+    return super.{self::Mixin::mixedInFieldImplementedMethod};
+  mixin-super-stub set mixedInFieldImplementedMethod(core::int value) → void
+    return super.{self::Mixin::mixedInFieldImplementedMethod} = value;
+  mixin-super-stub get extendedMethodMixedInField() → core::int
+    return super.{self::Mixin::extendedMethodMixedInField};
+  mixin-super-stub set extendedMethodMixedInField(core::int value) → void
+    return super.{self::Mixin::extendedMethodMixedInField} = value;
+  mixin-super-stub method mixedInMethodDeclaredGetter() → void
+    return super.{self::Mixin::mixedInMethodDeclaredGetter}();
+  mixin-super-stub method mixedInMethodDeclaredField() → void
+    return super.{self::Mixin::mixedInMethodDeclaredField}();
+  mixin-super-stub get mixedInGetterDeclaredMethod() → core::int
+    return super.{self::Mixin::mixedInGetterDeclaredMethod};
+  mixin-super-stub method mixedInMethodImplementedGetter() → void
+    return super.{self::Mixin::mixedInMethodImplementedGetter}();
+  mixin-super-stub method mixedInMethodImplementedSetter() → void
+    return super.{self::Mixin::mixedInMethodImplementedSetter}();
+  mixin-super-stub method mixedInMethodImplementedField() → void
+    return super.{self::Mixin::mixedInMethodImplementedField}();
+  mixin-super-stub get mixedInGetterImplementedMethod() → core::int
+    return super.{self::Mixin::mixedInGetterImplementedMethod};
+  mixin-super-stub get extendedMethodMixedInGetter() → core::int
+    return super.{self::Mixin::extendedMethodMixedInGetter};
+  mixin-super-stub method extendedGetterMixedInMethod() → void
+    return super.{self::Mixin::extendedGetterMixedInMethod}();
+  mixin-super-stub method extendedSetterMixedInMethod() → void
+    return super.{self::Mixin::extendedSetterMixedInMethod}();
+  mixin-super-stub method extendedFieldMixedInMethod() → void
+    return super.{self::Mixin::extendedFieldMixedInMethod}();
+  mixin-super-stub set mixedInSetterDeclaredMethod(core::int value) → void
+    return super.{self::Mixin::mixedInSetterDeclaredMethod} = value;
+  mixin-super-stub set mixedInSetterImplementedMethod(core::int value) → void
+    return super.{self::Mixin::mixedInSetterImplementedMethod} = value;
+  mixin-super-stub set extendedMethodMixedInSetter(core::int value) → void
+    return super.{self::Mixin::extendedMethodMixedInSetter} = value;
+}
+abstract class Class extends self::_Class&Super&Mixin implements self::Interface1, self::Interface2 {
+  field core::int extendedMethodDeclaredField = 0;
+  field core::int mixedInMethodDeclaredField = 0;
+  field core::int implementedMethodDeclaredField = 0;
+  synthetic constructor •() → self::Class
+    : super self::_Class&Super&Mixin::•()
+    ;
+  get extendedMethodDeclaredGetter() → core::int
+    return 0;
+  set extendedMethodDeclaredSetter(core::int value) → void {}
+  method extendedGetterDeclaredMethod() → void {}
+  method extendedSetterDeclaredMethod() → void {}
+  method extendedFieldDeclaredMethod() → void {}
+  get mixedInMethodDeclaredGetter() → core::int
+    return 0;
+  set mixedInMethodDeclaredSetter(core::int value) → void {}
+  method mixedInGetterDeclaredMethod() → void {}
+  method mixedInSetterDeclaredMethod() → void {}
+  method mixedInFieldDeclaredMethod() → void {}
+  get implementedMethodDeclaredGetter() → core::int
+    return 0;
+  set implementedMethodDeclaredSetter(core::int value) → void {}
+  method implementedGetterDeclaredMethod() → void {}
+  method implementedSetterDeclaredMethod() → void {}
+  method implementedFieldDeclaredMethod() → void {}
+  method declaredMethodAndSetter() → void {}
+  set declaredMethodAndSetter(core::int value) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/covariance.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/covariance.dart.weak.modular.expect
new file mode 100644
index 0000000..2e8e69d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/covariance.dart.weak.modular.expect
@@ -0,0 +1,152 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class M1 extends core::Object {
+  synthetic constructor •() → self::M1
+    : super core::Object::•()
+    ;
+  method method(covariant-by-declaration core::int a, core::int b) → dynamic {}
+}
+class M2 extends core::Object {
+  synthetic constructor •() → self::M2
+    : super core::Object::•()
+    ;
+  method method(core::int a, covariant-by-declaration core::int b) → dynamic {}
+}
+abstract class _C&Object&M1 = core::Object with self::M1 /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&M1
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(covariant-by-declaration core::int a, core::int b) → dynamic
+    return super.{self::M1::method}(a, b);
+}
+abstract class _C&Object&M1&M2 = self::_C&Object&M1 with self::M2 /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&M1&M2
+    : super self::_C&Object&M1::•()
+    ;
+  forwarding-stub method method(covariant-by-declaration core::int a, covariant-by-declaration core::int b) → dynamic
+    return super.{self::M2::method}(a, b);
+}
+class C extends self::_C&Object&M1&M2 {
+  synthetic constructor •() → self::C
+    : super self::_C&Object&M1&M2::•()
+    ;
+}
+class Direct extends core::Object {
+  synthetic constructor •() → self::Direct
+    : super core::Object::•()
+    ;
+  method positional(covariant-by-declaration core::int a, core::int b, covariant-by-declaration core::int c, core::int d, core::int e) → void {}
+  method optional([covariant-by-declaration core::int a = #C1, core::int b = #C1, covariant-by-declaration core::int c = #C1, core::int d = #C1]) → void {}
+  method named({covariant-by-declaration core::int a = #C1, core::int b = #C1, covariant-by-declaration core::int c = #C1, core::int d = #C1}) → void {}
+}
+class Inherited extends self::Direct {
+  synthetic constructor •() → self::Inherited
+    : super self::Direct::•()
+    ;
+}
+class Override1 extends core::Object {
+  synthetic constructor •() → self::Override1
+    : super core::Object::•()
+    ;
+  method method(covariant-by-declaration core::int a, core::int b, core::int c, core::int d, core::int e) → void {}
+}
+class Override2 extends self::Override1 {
+  synthetic constructor •() → self::Override2
+    : super self::Override1::•()
+    ;
+  method method(covariant-by-declaration core::int a, core::int b, covariant-by-declaration core::int c, core::int d, core::int e) → void {}
+}
+class Override3 extends self::Override2 {
+  synthetic constructor •() → self::Override3
+    : super self::Override2::•()
+    ;
+  method method(covariant-by-declaration core::int a, core::int b, covariant-by-declaration core::int c, core::int d, core::int e) → void {}
+}
+abstract class Implement1 extends core::Object {
+  synthetic constructor •() → self::Implement1
+    : super core::Object::•()
+    ;
+  method method(covariant-by-declaration core::int a, core::int b, core::int c, core::int d, core::int e) → void {}
+}
+class Implement2 extends core::Object {
+  synthetic constructor •() → self::Implement2
+    : super core::Object::•()
+    ;
+  method method(core::int a, covariant-by-declaration core::int b, core::int c, core::int d, core::int e) → void {}
+}
+class Implement3 extends core::Object {
+  synthetic constructor •() → self::Implement3
+    : super core::Object::•()
+    ;
+  method method(core::int a, core::int b, covariant-by-declaration core::int c, core::int d, core::int e) → void {}
+}
+class Implement4 extends core::Object implements self::Implement3 {
+  synthetic constructor •() → self::Implement4
+    : super core::Object::•()
+    ;
+  method method(core::int a, core::int b, covariant-by-declaration core::int c, covariant-by-declaration core::int d, core::int e) → void {}
+}
+class Implement5 extends core::Object implements self::Implement1, self::Implement2, self::Implement4 {
+  synthetic constructor •() → self::Implement5
+    : super core::Object::•()
+    ;
+  method method(covariant-by-declaration core::int a, covariant-by-declaration core::int b, covariant-by-declaration core::int c, covariant-by-declaration core::int d, covariant-by-declaration core::int e) → void {}
+}
+class Interface1 extends core::Object {
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+  method method(covariant-by-declaration core::int a, core::int b, core::int c, core::int d, core::int e) → void {}
+}
+class Interface2 extends core::Object {
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+  method method(core::int a, covariant-by-declaration core::int b, core::int c, core::int d, core::int e) → void {}
+}
+class Mixin1 extends core::Object {
+  synthetic constructor •() → self::Mixin1
+    : super core::Object::•()
+    ;
+  method method(core::int a, core::int b, covariant-by-declaration core::int c, core::int d, core::int e) → void {}
+}
+class Mixin2 extends core::Object {
+  synthetic constructor •() → self::Mixin2
+    : super core::Object::•()
+    ;
+  method method(core::int a, core::int b, core::int c, covariant-by-declaration core::int d, core::int e) → void {}
+}
+class Superclass extends core::Object {
+  synthetic constructor •() → self::Superclass
+    : super core::Object::•()
+    ;
+  method method(core::int a, core::int b, core::int c, core::int d, covariant-by-declaration core::int e) → void {}
+}
+abstract class _Mixed&Superclass&Mixin1 = self::Superclass with self::Mixin1 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Mixed&Superclass&Mixin1
+    : super self::Superclass::•()
+    ;
+  forwarding-stub method method(core::int a, core::int b, covariant-by-declaration core::int c, core::int d, covariant-by-declaration core::int e) → void
+    return super.{self::Mixin1::method}(a, b, c, d, e);
+}
+abstract class _Mixed&Superclass&Mixin1&Mixin2 = self::_Mixed&Superclass&Mixin1 with self::Mixin2 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Mixed&Superclass&Mixin1&Mixin2
+    : super self::_Mixed&Superclass&Mixin1::•()
+    ;
+  forwarding-stub method method(core::int a, core::int b, covariant-by-declaration core::int c, covariant-by-declaration core::int d, covariant-by-declaration core::int e) → void
+    return super.{self::Mixin2::method}(a, b, c, d, e);
+}
+class Mixed extends self::_Mixed&Superclass&Mixin1&Mixin2 implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::Mixed
+    : super self::_Mixed&Superclass&Mixin1&Mixin2::•()
+    ;
+  forwarding-stub method method(covariant-by-declaration core::int a, covariant-by-declaration core::int b, covariant-by-declaration core::int c, covariant-by-declaration core::int d, covariant-by-declaration core::int e) → void
+    return super.{self::Mixin2::method}(a, b, c, d, e);
+}
+static method main() → void {}
+
+constants  {
+  #C1 = 0
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/covariant_equals.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/covariant_equals.dart.weak.modular.expect
new file mode 100644
index 0000000..42a0eb1
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/covariant_equals.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator ==(covariant-by-declaration self::A* other) → core::bool*
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator ==(covariant-by-declaration self::A* other) → core::bool*
+    return true;
+}
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  operator ==(covariant-by-declaration covariant-by-class self::C<self::C::T*>* other) → core::bool*
+    return true;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C<core::int*> {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/declares.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/declares.dart.weak.modular.expect
new file mode 100644
index 0000000..50391f4
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/declares.dart.weak.modular.expect
@@ -0,0 +1,95 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/declares.dart:5:7: Error: The non-abstract class 'Super' is missing implementations for these members:
+//  - Super.extendedAbstractDeclaredAbstractMethod
+//  - Super.extendedAbstractDeclaredConcreteMethod
+//  - Super.extendedAbstractImplementedDeclaredAbstractMethod
+//  - Super.extendedAbstractImplementedDeclaredConcreteMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Super {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/declares.dart:12:8: Context: 'Super.extendedAbstractDeclaredAbstractMethod' is defined here.
+//   void extendedAbstractDeclaredAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/declares.dart:8:8: Context: 'Super.extendedAbstractDeclaredConcreteMethod' is defined here.
+//   void extendedAbstractDeclaredConcreteMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/declares.dart:20:8: Context: 'Super.extendedAbstractImplementedDeclaredAbstractMethod' is defined here.
+//   void extendedAbstractImplementedDeclaredAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/declares.dart:16:8: Context: 'Super.extendedAbstractImplementedDeclaredConcreteMethod' is defined here.
+//   void extendedAbstractImplementedDeclaredConcreteMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/declares.dart:37:7: Error: The non-abstract class 'Class' is missing implementations for these members:
+//  - Class.extendedAbstractDeclaredAbstractMethod
+//  - Class.extendedAbstractImplementedDeclaredAbstractMethod
+//  - Class.implementedDeclaredAbstractMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Class extends Super implements Interface {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/declares.dart:44:8: Context: 'Class.extendedAbstractDeclaredAbstractMethod' is defined here.
+//   void extendedAbstractDeclaredAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/declares.dart:56:8: Context: 'Class.extendedAbstractImplementedDeclaredAbstractMethod' is defined here.
+//   void extendedAbstractImplementedDeclaredAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/declares.dart:48:8: Context: 'Class.implementedDeclaredAbstractMethod' is defined here.
+//   void implementedDeclaredAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  method extendedConcreteDeclaredConcreteMethod() → void {}
+  abstract method extendedAbstractDeclaredConcreteMethod() → void;
+  method extendedConcreteDeclaredAbstractMethod() → void {}
+  abstract method extendedAbstractDeclaredAbstractMethod() → void;
+  method extendedConcreteImplementedDeclaredConcreteMethod() → void {}
+  abstract method extendedAbstractImplementedDeclaredConcreteMethod() → void;
+  method extendedConcreteImplementedDeclaredAbstractMethod() → void {}
+  abstract method extendedAbstractImplementedDeclaredAbstractMethod() → void;
+}
+class Interface extends core::Object {
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  method implementedDeclaredConcreteMethod() → void {}
+  method implementedDeclaredAbstractMethod() → void {}
+  method extendedConcreteImplementedDeclaredConcreteMethod() → void {}
+  method extendedAbstractImplementedDeclaredConcreteMethod() → void {}
+  method extendedConcreteImplementedDeclaredAbstractMethod() → void {}
+  method extendedAbstractImplementedDeclaredAbstractMethod() → void {}
+}
+class Class extends self::Super implements self::Interface {
+  synthetic constructor •() → self::Class
+    : super self::Super::•()
+    ;
+  method extendedConcreteDeclaredConcreteMethod() → void {}
+  method extendedAbstractDeclaredConcreteMethod() → void {}
+  abstract method extendedConcreteDeclaredAbstractMethod() → void;
+  abstract method extendedAbstractDeclaredAbstractMethod() → void;
+  method implementedDeclaredConcreteMethod() → void {}
+  abstract method implementedDeclaredAbstractMethod() → void;
+  method extendedConcreteImplementedDeclaredConcreteMethod() → void {}
+  method extendedAbstractImplementedDeclaredConcreteMethod() → void {}
+  abstract method extendedConcreteImplementedDeclaredAbstractMethod() → void;
+  abstract method extendedAbstractImplementedDeclaredAbstractMethod() → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart.weak.modular.expect
new file mode 100644
index 0000000..d51754d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart.weak.modular.expect
@@ -0,0 +1,132 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:7:11: Error: 'superDuplicate1' is already declared in this scope.
+//   int get superDuplicate1 => 42;
+//           ^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:6:8: Context: Previous declaration of 'superDuplicate1'.
+//   void superDuplicate1() {}
+//        ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:10:8: Error: 'superDuplicate2' is already declared in this scope.
+//   void superDuplicate2() {}
+//        ^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:9:11: Context: Previous declaration of 'superDuplicate2'.
+//   int get superDuplicate2 => 42;
+//           ^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:29:11: Error: 'interfaceDuplicate1' is already declared in this scope.
+//   int get interfaceDuplicate1 => 42;
+//           ^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:28:8: Context: Previous declaration of 'interfaceDuplicate1'.
+//   void interfaceDuplicate1() {}
+//        ^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:32:8: Error: 'interfaceDuplicate2' is already declared in this scope.
+//   void interfaceDuplicate2() {}
+//        ^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:31:11: Context: Previous declaration of 'interfaceDuplicate2'.
+//   int get interfaceDuplicate2 => 42;
+//           ^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:43:11: Error: 'extendedDuplicate1' is already declared in this scope.
+//   int get extendedDuplicate1 => 42;
+//           ^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:42:8: Context: Previous declaration of 'extendedDuplicate1'.
+//   void extendedDuplicate1() {}
+//        ^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:46:8: Error: 'extendedDuplicate2' is already declared in this scope.
+//   void extendedDuplicate2() {}
+//        ^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:45:11: Context: Previous declaration of 'extendedDuplicate2'.
+//   int get extendedDuplicate2 => 42;
+//           ^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:52:11: Error: 'mixedInDuplicate1' is already declared in this scope.
+//   int get mixedInDuplicate1 => 42;
+//           ^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:51:8: Context: Previous declaration of 'mixedInDuplicate1'.
+//   void mixedInDuplicate1() {}
+//        ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:55:8: Error: 'mixedInDuplicate2' is already declared in this scope.
+//   void mixedInDuplicate2() {}
+//        ^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:54:11: Context: Previous declaration of 'mixedInDuplicate2'.
+//   int get mixedInDuplicate2 => 42;
+//           ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:61:11: Error: 'implementedDuplicate1' is already declared in this scope.
+//   int get implementedDuplicate1 => 42;
+//           ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:60:8: Context: Previous declaration of 'implementedDuplicate1'.
+//   void implementedDuplicate1() {}
+//        ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:64:8: Error: 'implementedDuplicate2' is already declared in this scope.
+//   void implementedDuplicate2() {}
+//        ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/duplicates.dart:63:11: Context: Previous declaration of 'implementedDuplicate2'.
+//   int get implementedDuplicate2 => 42;
+//           ^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  method superDuplicate1() → void {}
+  get superDuplicate2() → core::int
+    return 42;
+  method extendedDuplicate1() → void {}
+  method extendedDuplicate2() → void {}
+}
+class Mixin extends core::Object {
+  synthetic constructor •() → self::Mixin
+    : super core::Object::•()
+    ;
+  method mixedInDuplicate1() → void {}
+  method mixedInDuplicate2() → void {}
+}
+class Interface extends core::Object {
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  method interfaceDuplicate1() → void {}
+  get interfaceDuplicate2() → core::int
+    return 42;
+  method implementedDuplicate1() → void {}
+  method implementedDuplicate2() → void {}
+}
+abstract class _Class&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&Mixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub method mixedInDuplicate1() → void
+    return super.{self::Mixin::mixedInDuplicate1}();
+  mixin-super-stub method mixedInDuplicate2() → void
+    return super.{self::Mixin::mixedInDuplicate2}();
+}
+abstract class Class extends self::_Class&Super&Mixin implements self::Interface {
+  synthetic constructor •() → self::Class
+    : super self::_Class&Super&Mixin::•()
+    ;
+  method superDuplicate1() → void {}
+  method superDuplicate2() → void {}
+  method extendedDuplicate1() → void {}
+  get extendedDuplicate2() → core::int
+    return 42;
+  method mixedInDuplicate1() → void {}
+  get mixedInDuplicate2() → core::int
+    return 42;
+  method interfaceDuplicate1() → void {}
+  method interfaceDuplicate2() → void {}
+  method implementedDuplicate1() → void {}
+  get implementedDuplicate2() → core::int
+    return 42;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart.weak.modular.expect
new file mode 100644
index 0000000..becdaa6
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart.weak.modular.expect
@@ -0,0 +1,145 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:37:7: Error: The non-abstract class 'ConcreteSub' is missing implementations for these members:
+//  - Interface1.extendedAbstractImplementedField
+//  - Interface1.extendedAbstractImplementedMultipleField
+//  - Interface2.extendedAbstractImplementedMultipleField
+//  - Super.extendedAbstractField
+//  - Super.extendedAbstractField=
+//  - Super.extendedAbstractImplementedField
+//  - Super.extendedAbstractImplementedField=
+//  - Super.extendedAbstractImplementedMultipleField
+//  - Super.extendedAbstractImplementedMultipleField=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSub extends AbstractClass {}
+//       ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:22:7: Context: 'Interface1.extendedAbstractImplementedField' is defined here.
+//   int extendedAbstractImplementedField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:26:7: Context: 'Interface1.extendedAbstractImplementedMultipleField' is defined here.
+//   int extendedAbstractImplementedMultipleField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:32:7: Context: 'Interface2.extendedAbstractImplementedMultipleField' is defined here.
+//   int extendedAbstractImplementedMultipleField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:8:16: Context: 'Super.extendedAbstractField' is defined here.
+//   abstract int extendedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:8:16: Context: 'Super.extendedAbstractField=' is defined here.
+//   abstract int extendedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:12:16: Context: 'Super.extendedAbstractImplementedField' is defined here.
+//   abstract int extendedAbstractImplementedField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:12:16: Context: 'Super.extendedAbstractImplementedField=' is defined here.
+//   abstract int extendedAbstractImplementedField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:16:16: Context: 'Super.extendedAbstractImplementedMultipleField' is defined here.
+//   abstract int extendedAbstractImplementedMultipleField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:16:16: Context: 'Super.extendedAbstractImplementedMultipleField=' is defined here.
+//   abstract int extendedAbstractImplementedMultipleField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:39:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - Interface1.extendedAbstractImplementedField
+//  - Interface1.extendedAbstractImplementedMultipleField
+//  - Interface2.extendedAbstractImplementedMultipleField
+//  - Super.extendedAbstractField
+//  - Super.extendedAbstractField=
+//  - Super.extendedAbstractImplementedField
+//  - Super.extendedAbstractImplementedField=
+//  - Super.extendedAbstractImplementedMultipleField
+//  - Super.extendedAbstractImplementedMultipleField=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass extends Super implements Interface1, Interface2 {}
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:22:7: Context: 'Interface1.extendedAbstractImplementedField' is defined here.
+//   int extendedAbstractImplementedField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:26:7: Context: 'Interface1.extendedAbstractImplementedMultipleField' is defined here.
+//   int extendedAbstractImplementedMultipleField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:32:7: Context: 'Interface2.extendedAbstractImplementedMultipleField' is defined here.
+//   int extendedAbstractImplementedMultipleField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:8:16: Context: 'Super.extendedAbstractField' is defined here.
+//   abstract int extendedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:8:16: Context: 'Super.extendedAbstractField=' is defined here.
+//   abstract int extendedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:12:16: Context: 'Super.extendedAbstractImplementedField' is defined here.
+//   abstract int extendedAbstractImplementedField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:12:16: Context: 'Super.extendedAbstractImplementedField=' is defined here.
+//   abstract int extendedAbstractImplementedField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:16:16: Context: 'Super.extendedAbstractImplementedMultipleField' is defined here.
+//   abstract int extendedAbstractImplementedMultipleField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_field.dart:16:16: Context: 'Super.extendedAbstractImplementedMultipleField=' is defined here.
+//   abstract int extendedAbstractImplementedMultipleField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Super extends core::Object {
+  field core::int extendedConcreteField = 0;
+  field core::int extendedConcreteImplementedField = 0;
+  field core::int extendedConcreteImplementedMultipleField = 0;
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  abstract get extendedAbstractField() → core::int;
+  abstract set extendedAbstractField(core::int #externalFieldValue) → void;
+  abstract get extendedAbstractImplementedField() → core::int;
+  abstract set extendedAbstractImplementedField(core::int #externalFieldValue) → void;
+  abstract get extendedAbstractImplementedMultipleField() → core::int;
+  abstract set extendedAbstractImplementedMultipleField(core::int #externalFieldValue) → void;
+}
+class Interface1 extends core::Object {
+  field core::int extendedConcreteImplementedField = 0;
+  field core::int extendedAbstractImplementedField = 0;
+  field core::int extendedConcreteImplementedMultipleField = 0;
+  field core::int extendedAbstractImplementedMultipleField = 0;
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+}
+class Interface2 extends core::Object {
+  field core::int extendedConcreteImplementedMultipleField = 0;
+  field core::int extendedAbstractImplementedMultipleField = 0;
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+}
+abstract class AbstractClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::AbstractClass
+    : super self::Super::•()
+    ;
+}
+class ConcreteSub extends self::AbstractClass {
+  synthetic constructor •() → self::ConcreteSub
+    : super self::AbstractClass::•()
+    ;
+}
+class ConcreteClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::ConcreteClass
+    : super self::Super::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart.weak.modular.expect
new file mode 100644
index 0000000..e65fe64
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart.weak.modular.expect
@@ -0,0 +1,118 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart:37:7: Error: The non-abstract class 'ConcreteSub' is missing implementations for these members:
+//  - Interface1.extendedAbstractImplementedField
+//  - Interface1.extendedAbstractImplementedMultipleField
+//  - Interface2.extendedAbstractImplementedMultipleField
+//  - Super.extendedAbstractField
+//  - Super.extendedAbstractImplementedField
+//  - Super.extendedAbstractImplementedMultipleField
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSub extends AbstractClass {}
+//       ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart:22:13: Context: 'Interface1.extendedAbstractImplementedField' is defined here.
+//   final int extendedAbstractImplementedField = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart:26:13: Context: 'Interface1.extendedAbstractImplementedMultipleField' is defined here.
+//   final int extendedAbstractImplementedMultipleField = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart:32:13: Context: 'Interface2.extendedAbstractImplementedMultipleField' is defined here.
+//   final int extendedAbstractImplementedMultipleField = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart:8:22: Context: 'Super.extendedAbstractField' is defined here.
+//   abstract final int extendedAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart:12:22: Context: 'Super.extendedAbstractImplementedField' is defined here.
+//   abstract final int extendedAbstractImplementedField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart:16:22: Context: 'Super.extendedAbstractImplementedMultipleField' is defined here.
+//   abstract final int extendedAbstractImplementedMultipleField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart:39:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - Interface1.extendedAbstractImplementedField
+//  - Interface1.extendedAbstractImplementedMultipleField
+//  - Interface2.extendedAbstractImplementedMultipleField
+//  - Super.extendedAbstractField
+//  - Super.extendedAbstractImplementedField
+//  - Super.extendedAbstractImplementedMultipleField
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass extends Super implements Interface1, Interface2 {}
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart:22:13: Context: 'Interface1.extendedAbstractImplementedField' is defined here.
+//   final int extendedAbstractImplementedField = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart:26:13: Context: 'Interface1.extendedAbstractImplementedMultipleField' is defined here.
+//   final int extendedAbstractImplementedMultipleField = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart:32:13: Context: 'Interface2.extendedAbstractImplementedMultipleField' is defined here.
+//   final int extendedAbstractImplementedMultipleField = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart:8:22: Context: 'Super.extendedAbstractField' is defined here.
+//   abstract final int extendedAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart:12:22: Context: 'Super.extendedAbstractImplementedField' is defined here.
+//   abstract final int extendedAbstractImplementedField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_final_field.dart:16:22: Context: 'Super.extendedAbstractImplementedMultipleField' is defined here.
+//   abstract final int extendedAbstractImplementedMultipleField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Super extends core::Object {
+  final field core::int extendedConcreteField = 0;
+  final field core::int extendedConcreteImplementedField = 0;
+  final field core::int extendedConcreteImplementedMultipleField = 0;
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  abstract get extendedAbstractField() → core::int;
+  abstract get extendedAbstractImplementedField() → core::int;
+  abstract get extendedAbstractImplementedMultipleField() → core::int;
+}
+class Interface1 extends core::Object {
+  final field core::int extendedConcreteImplementedField = 0;
+  final field core::int extendedAbstractImplementedField = 0;
+  final field core::int extendedConcreteImplementedMultipleField = 0;
+  final field core::int extendedAbstractImplementedMultipleField = 0;
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+}
+class Interface2 extends core::Object {
+  final field core::int extendedConcreteImplementedMultipleField = 0;
+  final field core::int extendedAbstractImplementedMultipleField = 0;
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+}
+abstract class AbstractClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::AbstractClass
+    : super self::Super::•()
+    ;
+}
+class ConcreteSub extends self::AbstractClass {
+  synthetic constructor •() → self::ConcreteSub
+    : super self::AbstractClass::•()
+    ;
+}
+class ConcreteClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::ConcreteClass
+    : super self::Super::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..39f968f
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart.weak.modular.expect
@@ -0,0 +1,127 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart:37:7: Error: The non-abstract class 'ConcreteSub' is missing implementations for these members:
+//  - Interface1.extendedAbstractImplementedGetter
+//  - Interface1.extendedAbstractImplementedMultipleGetter
+//  - Interface2.extendedAbstractImplementedMultipleGetter
+//  - Super.extendedAbstractGetter
+//  - Super.extendedAbstractImplementedGetter
+//  - Super.extendedAbstractImplementedMultipleGetter
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSub extends AbstractClass {}
+//       ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart:22:11: Context: 'Interface1.extendedAbstractImplementedGetter' is defined here.
+//   int get extendedAbstractImplementedGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart:26:11: Context: 'Interface1.extendedAbstractImplementedMultipleGetter' is defined here.
+//   int get extendedAbstractImplementedMultipleGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart:32:11: Context: 'Interface2.extendedAbstractImplementedMultipleGetter' is defined here.
+//   int get extendedAbstractImplementedMultipleGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart:8:11: Context: 'Super.extendedAbstractGetter' is defined here.
+//   int get extendedAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart:12:11: Context: 'Super.extendedAbstractImplementedGetter' is defined here.
+//   int get extendedAbstractImplementedGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart:16:11: Context: 'Super.extendedAbstractImplementedMultipleGetter' is defined here.
+//   int get extendedAbstractImplementedMultipleGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart:39:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - Interface1.extendedAbstractImplementedGetter
+//  - Interface1.extendedAbstractImplementedMultipleGetter
+//  - Interface2.extendedAbstractImplementedMultipleGetter
+//  - Super.extendedAbstractGetter
+//  - Super.extendedAbstractImplementedGetter
+//  - Super.extendedAbstractImplementedMultipleGetter
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass extends Super implements Interface1, Interface2 {}
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart:22:11: Context: 'Interface1.extendedAbstractImplementedGetter' is defined here.
+//   int get extendedAbstractImplementedGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart:26:11: Context: 'Interface1.extendedAbstractImplementedMultipleGetter' is defined here.
+//   int get extendedAbstractImplementedMultipleGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart:32:11: Context: 'Interface2.extendedAbstractImplementedMultipleGetter' is defined here.
+//   int get extendedAbstractImplementedMultipleGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart:8:11: Context: 'Super.extendedAbstractGetter' is defined here.
+//   int get extendedAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart:12:11: Context: 'Super.extendedAbstractImplementedGetter' is defined here.
+//   int get extendedAbstractImplementedGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_getter.dart:16:11: Context: 'Super.extendedAbstractImplementedMultipleGetter' is defined here.
+//   int get extendedAbstractImplementedMultipleGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  get extendedConcreteGetter() → core::int
+    return 0;
+  abstract get extendedAbstractGetter() → core::int;
+  get extendedConcreteImplementedGetter() → core::int
+    return 0;
+  abstract get extendedAbstractImplementedGetter() → core::int;
+  get extendedConcreteImplementedMultipleGetter() → core::int
+    return 0;
+  abstract get extendedAbstractImplementedMultipleGetter() → core::int;
+}
+class Interface1 extends core::Object {
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+  get extendedConcreteImplementedGetter() → core::int
+    return 0;
+  get extendedAbstractImplementedGetter() → core::int
+    return 0;
+  get extendedConcreteImplementedMultipleGetter() → core::int
+    return 0;
+  get extendedAbstractImplementedMultipleGetter() → core::int
+    return 0;
+}
+class Interface2 extends core::Object {
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+  get extendedConcreteImplementedMultipleGetter() → core::int
+    return 0;
+  get extendedAbstractImplementedMultipleGetter() → core::int
+    return 0;
+}
+abstract class AbstractClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::AbstractClass
+    : super self::Super::•()
+    ;
+}
+class ConcreteSub extends self::AbstractClass {
+  synthetic constructor •() → self::ConcreteSub
+    : super self::AbstractClass::•()
+    ;
+}
+class ConcreteClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::ConcreteClass
+    : super self::Super::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart.weak.modular.expect
new file mode 100644
index 0000000..2bb4d30
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart.weak.modular.expect
@@ -0,0 +1,118 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart:37:7: Error: The non-abstract class 'ConcreteSub' is missing implementations for these members:
+//  - Interface1.extendedAbstractImplementedMethod
+//  - Interface1.extendedAbstractImplementedMultipleMethod
+//  - Interface2.extendedAbstractImplementedMultipleMethod
+//  - Super.extendedAbstractImplementedMethod
+//  - Super.extendedAbstractImplementedMultipleMethod
+//  - Super.extendedAbstractMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSub extends AbstractClass {}
+//       ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart:22:8: Context: 'Interface1.extendedAbstractImplementedMethod' is defined here.
+//   void extendedAbstractImplementedMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart:26:8: Context: 'Interface1.extendedAbstractImplementedMultipleMethod' is defined here.
+//   void extendedAbstractImplementedMultipleMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart:32:8: Context: 'Interface2.extendedAbstractImplementedMultipleMethod' is defined here.
+//   void extendedAbstractImplementedMultipleMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart:12:8: Context: 'Super.extendedAbstractImplementedMethod' is defined here.
+//   void extendedAbstractImplementedMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart:16:8: Context: 'Super.extendedAbstractImplementedMultipleMethod' is defined here.
+//   void extendedAbstractImplementedMultipleMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart:8:8: Context: 'Super.extendedAbstractMethod' is defined here.
+//   void extendedAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart:39:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - Interface1.extendedAbstractImplementedMethod
+//  - Interface1.extendedAbstractImplementedMultipleMethod
+//  - Interface2.extendedAbstractImplementedMultipleMethod
+//  - Super.extendedAbstractImplementedMethod
+//  - Super.extendedAbstractImplementedMultipleMethod
+//  - Super.extendedAbstractMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass extends Super implements Interface1, Interface2 {}
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart:22:8: Context: 'Interface1.extendedAbstractImplementedMethod' is defined here.
+//   void extendedAbstractImplementedMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart:26:8: Context: 'Interface1.extendedAbstractImplementedMultipleMethod' is defined here.
+//   void extendedAbstractImplementedMultipleMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart:32:8: Context: 'Interface2.extendedAbstractImplementedMultipleMethod' is defined here.
+//   void extendedAbstractImplementedMultipleMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart:12:8: Context: 'Super.extendedAbstractImplementedMethod' is defined here.
+//   void extendedAbstractImplementedMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart:16:8: Context: 'Super.extendedAbstractImplementedMultipleMethod' is defined here.
+//   void extendedAbstractImplementedMultipleMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_method.dart:8:8: Context: 'Super.extendedAbstractMethod' is defined here.
+//   void extendedAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  method extendedConcreteMethod() → void {}
+  abstract method extendedAbstractMethod() → void;
+  method extendedConcreteImplementedMethod() → void {}
+  abstract method extendedAbstractImplementedMethod() → void;
+  method extendedConcreteImplementedMultipleMethod() → void {}
+  abstract method extendedAbstractImplementedMultipleMethod() → void;
+}
+class Interface1 extends core::Object {
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+  method extendedConcreteImplementedMethod() → void {}
+  method extendedAbstractImplementedMethod() → void {}
+  method extendedConcreteImplementedMultipleMethod() → void {}
+  method extendedAbstractImplementedMultipleMethod() → void {}
+}
+class Interface2 extends core::Object {
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+  method extendedConcreteImplementedMultipleMethod() → void {}
+  method extendedAbstractImplementedMultipleMethod() → void {}
+}
+abstract class AbstractClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::AbstractClass
+    : super self::Super::•()
+    ;
+}
+class ConcreteSub extends self::AbstractClass {
+  synthetic constructor •() → self::ConcreteSub
+    : super self::AbstractClass::•()
+    ;
+}
+class ConcreteClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::ConcreteClass
+    : super self::Super::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..e2cfcb3
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart.weak.modular.expect
@@ -0,0 +1,118 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart:37:7: Error: The non-abstract class 'ConcreteSub' is missing implementations for these members:
+//  - Interface1.extendedAbstractImplementedMultipleSetter=
+//  - Interface1.extendedAbstractImplementedSetter=
+//  - Interface2.extendedAbstractImplementedMultipleSetter=
+//  - Super.extendedAbstractImplementedMultipleSetter=
+//  - Super.extendedAbstractImplementedSetter=
+//  - Super.extendedAbstractSetter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSub extends AbstractClass {}
+//       ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart:26:12: Context: 'Interface1.extendedAbstractImplementedMultipleSetter=' is defined here.
+//   void set extendedAbstractImplementedMultipleSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart:22:12: Context: 'Interface1.extendedAbstractImplementedSetter=' is defined here.
+//   void set extendedAbstractImplementedSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart:32:12: Context: 'Interface2.extendedAbstractImplementedMultipleSetter=' is defined here.
+//   void set extendedAbstractImplementedMultipleSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart:16:12: Context: 'Super.extendedAbstractImplementedMultipleSetter=' is defined here.
+//   void set extendedAbstractImplementedMultipleSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart:12:12: Context: 'Super.extendedAbstractImplementedSetter=' is defined here.
+//   void set extendedAbstractImplementedSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart:8:12: Context: 'Super.extendedAbstractSetter=' is defined here.
+//   void set extendedAbstractSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart:39:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - Interface1.extendedAbstractImplementedMultipleSetter=
+//  - Interface1.extendedAbstractImplementedSetter=
+//  - Interface2.extendedAbstractImplementedMultipleSetter=
+//  - Super.extendedAbstractImplementedMultipleSetter=
+//  - Super.extendedAbstractImplementedSetter=
+//  - Super.extendedAbstractSetter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass extends Super implements Interface1, Interface2 {}
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart:26:12: Context: 'Interface1.extendedAbstractImplementedMultipleSetter=' is defined here.
+//   void set extendedAbstractImplementedMultipleSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart:22:12: Context: 'Interface1.extendedAbstractImplementedSetter=' is defined here.
+//   void set extendedAbstractImplementedSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart:32:12: Context: 'Interface2.extendedAbstractImplementedMultipleSetter=' is defined here.
+//   void set extendedAbstractImplementedMultipleSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart:16:12: Context: 'Super.extendedAbstractImplementedMultipleSetter=' is defined here.
+//   void set extendedAbstractImplementedMultipleSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart:12:12: Context: 'Super.extendedAbstractImplementedSetter=' is defined here.
+//   void set extendedAbstractImplementedSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/extend_multiple_setter.dart:8:12: Context: 'Super.extendedAbstractSetter=' is defined here.
+//   void set extendedAbstractSetter(int value);
+//            ^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  set extendedConcreteSetter(core::int value) → void {}
+  abstract set extendedAbstractSetter(core::int value) → void;
+  set extendedConcreteImplementedSetter(core::int value) → void {}
+  abstract set extendedAbstractImplementedSetter(core::int value) → void;
+  set extendedConcreteImplementedMultipleSetter(core::int value) → void {}
+  abstract set extendedAbstractImplementedMultipleSetter(core::int value) → void;
+}
+class Interface1 extends core::Object {
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+  set extendedConcreteImplementedSetter(core::int value) → void {}
+  set extendedAbstractImplementedSetter(core::int value) → void {}
+  set extendedConcreteImplementedMultipleSetter(core::int value) → void {}
+  set extendedAbstractImplementedMultipleSetter(core::int value) → void {}
+}
+class Interface2 extends core::Object {
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+  set extendedConcreteImplementedMultipleSetter(core::int value) → void {}
+  set extendedAbstractImplementedMultipleSetter(core::int value) → void {}
+}
+abstract class AbstractClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::AbstractClass
+    : super self::Super::•()
+    ;
+}
+class ConcreteSub extends self::AbstractClass {
+  synthetic constructor •() → self::ConcreteSub
+    : super self::AbstractClass::•()
+    ;
+}
+class ConcreteClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::ConcreteClass
+    : super self::Super::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart.weak.modular.expect
new file mode 100644
index 0000000..5a2032c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart.weak.modular.expect
@@ -0,0 +1,144 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:24:19: Error: The return type of the method 'Class.field2' is 'String', which does not match the return type, 'num', of the overridden method, 'Super.field2'.
+// Change to a subtype of 'num'.
+//   abstract String field2;
+//                   ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:7:7: Context: This is the overridden method ('field2').
+//   num field2 = 0;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:24:19: Error: The return type of the method 'Class.field2' is 'String', which does not match the return type, 'int', of the overridden method, 'Interface.field2'.
+// Change to a subtype of 'int'.
+//   abstract String field2;
+//                   ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:16:17: Context: This is the overridden method ('field2').
+//   covariant int field2 = 0;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:24:19: Error: The parameter '#externalFieldValue' of the method 'Class.field2' has type 'String', which does not match the corresponding type, 'num', in the overridden method, 'Super.field2'.
+// Change to a supertype of 'num', or, for a covariant parameter, a subtype.
+//   abstract String field2;
+//                   ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:7:7: Context: This is the overridden method ('field2').
+//   num field2 = 0;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:24:19: Error: The parameter '#externalFieldValue' of the method 'Class.field2' has type 'String', which does not match the corresponding type, 'int', in the overridden method, 'Interface.field2'.
+// Change to a supertype of 'int', or, for a covariant parameter, a subtype.
+//   abstract String field2;
+//                   ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:16:17: Context: This is the overridden method ('field2').
+//   covariant int field2 = 0;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:25:16: Error: The parameter '#externalFieldValue' of the method 'Class.field3' has type 'int', which does not match the corresponding type, 'num', in the overridden method, 'Super.field3'.
+// Change to a supertype of 'num', or, for a covariant parameter, a subtype.
+//   abstract int field3;
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:8:7: Context: This is the overridden method ('field3').
+//   num field3 = 0;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:28:16: Error: The return type of the method 'Class.field5' is 'num', which does not match the return type, 'int', of the overridden method, 'Super.field5'.
+// Change to a subtype of 'int'.
+//   abstract num field5;
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:11:17: Context: This is the overridden method ('field5').
+//   covariant int field5 = 0;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:28:16: Error: The return type of the method 'Class.field5' is 'num', which does not match the return type, 'int', of the overridden method, 'Interface.field5'.
+// Change to a subtype of 'int'.
+//   abstract num field5;
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:19:7: Context: This is the overridden method ('field5').
+//   int field5 = 0;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:22:7: Error: The implementation of 'field1' in the non-abstract class 'Class' does not conform to its interface.
+// class Class extends Super implements Interface {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:6:7: Context: The return type of the method 'Super.field1' is 'num', which does not match the return type, 'int', of the overridden method, 'Class.field1'.
+// Change to a subtype of 'int'.
+//   num field1 = 0;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:23:16: Context: This is the overridden method ('field1').
+//   abstract int field1;
+//                ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:22:7: Error: The implementation of 'field2' in the non-abstract class 'Class' does not conform to its interface.
+// class Class extends Super implements Interface {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:7:7: Context: The return type of the method 'Super.field2' is 'num', which does not match the return type, 'String', of the overridden method, 'Class.field2'.
+// Change to a subtype of 'String'.
+//   num field2 = 0;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:24:19: Context: This is the overridden method ('field2').
+//   abstract String field2;
+//                   ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:22:7: Error: The implementation of 'field3' in the non-abstract class 'Class' does not conform to its interface.
+// class Class extends Super implements Interface {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:8:7: Context: The return type of the method 'Super.field3' is 'num', which does not match the return type, 'int', of the overridden method, 'Class.field3'.
+// Change to a subtype of 'int'.
+//   num field3 = 0;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:25:16: Context: This is the overridden method ('field3').
+//   abstract int field3;
+//                ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:22:7: Error: The implementation of 'field4' in the non-abstract class 'Class' does not conform to its interface.
+// class Class extends Super implements Interface {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:10:17: Context: The return type of the method 'Super.field4' is 'num', which does not match the return type, 'int', of the overridden method, 'Class.field4'.
+// Change to a subtype of 'int'.
+//   covariant num field4 = 0;
+//                 ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_field.dart:27:16: Context: This is the overridden method ('field4').
+//   abstract int field4;
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  field core::num field1 = 0;
+  field core::num field2 = 0;
+  field core::num field3 = 0;
+  covariant-by-declaration field core::num field4 = 0;
+  covariant-by-declaration field core::int field5 = 0;
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+}
+class Interface extends core::Object {
+  covariant-by-declaration field core::int field1 = 0;
+  covariant-by-declaration field core::int field2 = 0;
+  field core::int field4 = 0;
+  field core::int field5 = 0;
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+}
+class Class extends self::Super implements self::Interface {
+  synthetic constructor •() → self::Class
+    : super self::Super::•()
+    ;
+  abstract get field1() → core::int;
+  forwarding-stub forwarding-semi-stub set /* signature-type: (core::int) → void */ field1(covariant-by-declaration core::num #externalFieldValue) → void
+    return super.{self::Super::field1} = #externalFieldValue;
+  abstract get field2() → core::String;
+  forwarding-stub forwarding-semi-stub set /* signature-type: (core::String) → void */ field2(covariant-by-declaration core::num #externalFieldValue) → void
+    return super.{self::Super::field2} = #externalFieldValue;
+  abstract get field3() → core::int;
+  abstract set field3(core::int #externalFieldValue) → void;
+  abstract get field4() → core::int;
+  abstract set field4(covariant-by-declaration core::int #externalFieldValue) → void;
+  abstract get field5() → core::num;
+  abstract set field5(covariant-by-declaration core::num #externalFieldValue) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_method.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_method.dart.weak.modular.expect
new file mode 100644
index 0000000..9e7d45a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_method.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_method.dart:24:23: Error: The parameter 'i' of the method 'Class.method2' has type 'String', which does not match the corresponding type, 'num', in the overridden method, 'Super.method2'.
+// Change to a supertype of 'num', or, for a covariant parameter, a subtype.
+//   void method2(String i);
+//                       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_method.dart:7:8: Context: This is the overridden method ('method2').
+//   void method2(num n) {}
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_method.dart:24:23: Error: The parameter 'i' of the method 'Class.method2' has type 'String', which does not match the corresponding type, 'int', in the overridden method, 'Interface.method2'.
+// Change to a supertype of 'int', or, for a covariant parameter, a subtype.
+//   void method2(String i);
+//                       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_method.dart:16:8: Context: This is the overridden method ('method2').
+//   void method2(covariant int i) {}
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_method.dart:25:20: Error: The parameter 'i' of the method 'Class.method3' has type 'int', which does not match the corresponding type, 'num', in the overridden method, 'Super.method3'.
+// Change to a supertype of 'num', or, for a covariant parameter, a subtype.
+//   void method3(int i);
+//                    ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_method.dart:8:8: Context: This is the overridden method ('method3').
+//   void method3(num n) {}
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_method.dart:22:7: Error: The implementation of 'method2' in the non-abstract class 'Class' does not conform to its interface.
+// class Class extends Super implements Interface {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_method.dart:7:20: Context: The parameter 'n' of the method 'Super.method2' has type 'num', which does not match the corresponding type, 'String', in the overridden method, 'Class.method2'.
+// Change to a supertype of 'String', or, for a covariant parameter, a subtype.
+//   void method2(num n) {}
+//                    ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_method.dart:24:8: Context: This is the overridden method ('method2').
+//   void method2(String i);
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  method method1(core::num n) → void {}
+  method method2(core::num n) → void {}
+  method method3(core::num n) → void {}
+  method method4(covariant-by-declaration core::num i) → void {}
+  method method5(covariant-by-declaration core::int i) → void {}
+}
+class Interface extends core::Object {
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  method method1(covariant-by-declaration core::int i) → void {}
+  method method2(covariant-by-declaration core::int i) → void {}
+  method method4(core::int i) → void {}
+  method method5(core::int i) → void {}
+}
+class Class extends self::Super implements self::Interface {
+  synthetic constructor •() → self::Class
+    : super self::Super::•()
+    ;
+  forwarding-stub forwarding-semi-stub method /* signature-type: (core::int) → void */ method1(covariant-by-declaration core::num i) → void
+    return super.{self::Super::method1}(i);
+  forwarding-stub forwarding-semi-stub method /* signature-type: (core::String) → void */ method2(covariant-by-declaration core::num i) → void
+    return super.{self::Super::method2}(i);
+  abstract method method3(core::int i) → void;
+  abstract method method4(covariant-by-declaration core::int i) → void;
+  abstract method method5(covariant-by-declaration core::num n) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_setter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..a51aa61
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_setter.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_setter.dart:24:27: Error: The parameter 'i' of the method 'Class.setter2' has type 'String', which does not match the corresponding type, 'num', in the overridden method, 'Super.setter2'.
+// Change to a supertype of 'num', or, for a covariant parameter, a subtype.
+//   void set setter2(String i);
+//                           ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_setter.dart:7:12: Context: This is the overridden method ('setter2').
+//   void set setter2(num n) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_setter.dart:24:27: Error: The parameter 'i' of the method 'Class.setter2' has type 'String', which does not match the corresponding type, 'int', in the overridden method, 'Interface.setter2'.
+// Change to a supertype of 'int', or, for a covariant parameter, a subtype.
+//   void set setter2(String i);
+//                           ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_setter.dart:16:12: Context: This is the overridden method ('setter2').
+//   void set setter2(covariant int i) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_setter.dart:25:24: Error: The parameter 'i' of the method 'Class.setter3' has type 'int', which does not match the corresponding type, 'num', in the overridden method, 'Super.setter3'.
+// Change to a supertype of 'num', or, for a covariant parameter, a subtype.
+//   void set setter3(int i);
+//                        ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_setter.dart:8:12: Context: This is the overridden method ('setter3').
+//   void set setter3(num n) {}
+//            ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_setter.dart:22:7: Error: The implementation of 'setter2' in the non-abstract class 'Class' does not conform to its interface.
+// class Class extends Super implements Interface {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_setter.dart:7:24: Context: The parameter 'n' of the method 'Super.setter2' has type 'num', which does not match the corresponding type, 'String', in the overridden method, 'Class.setter2'.
+// Change to a supertype of 'String', or, for a covariant parameter, a subtype.
+//   void set setter2(num n) {}
+//                        ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_semi_stub_setter.dart:24:12: Context: This is the overridden method ('setter2').
+//   void set setter2(String i);
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  set setter1(core::num n) → void {}
+  set setter2(core::num n) → void {}
+  set setter3(core::num n) → void {}
+  set setter4(covariant-by-declaration core::num i) → void {}
+  set setter5(covariant-by-declaration core::int i) → void {}
+}
+class Interface extends core::Object {
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  set setter1(covariant-by-declaration core::int i) → void {}
+  set setter2(covariant-by-declaration core::int i) → void {}
+  set setter4(core::int i) → void {}
+  set setter5(core::int i) → void {}
+}
+class Class extends self::Super implements self::Interface {
+  synthetic constructor •() → self::Class
+    : super self::Super::•()
+    ;
+  forwarding-stub forwarding-semi-stub set /* signature-type: (core::int) → void */ setter1(covariant-by-declaration core::num i) → void
+    return super.{self::Super::setter1} = i;
+  forwarding-stub forwarding-semi-stub set /* signature-type: (core::String) → void */ setter2(covariant-by-declaration core::num i) → void
+    return super.{self::Super::setter2} = i;
+  abstract set setter3(core::int i) → void;
+  abstract set setter4(covariant-by-declaration core::int i) → void;
+  abstract set setter5(covariant-by-declaration core::num n) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stub_call.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stub_call.dart.weak.modular.expect
new file mode 100644
index 0000000..a15a8cc
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stub_call.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Super<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Super<self::Super::T%>
+    : super core::Object::•()
+    ;
+  method method(covariant-by-class self::Super::T% t) → void {}
+}
+class Mixin extends core::Object {
+  synthetic constructor •() → self::Mixin
+    : super core::Object::•()
+    ;
+  method method(core::int t) → void {}
+}
+class Class = self::Super<core::int> with self::Mixin {
+  synthetic constructor •() → self::Class
+    : super self::Super::•()
+    ;
+  forwarding-stub method method(covariant-by-class core::int t) → void
+    return super.{self::Mixin::method}(t);
+}
+class Subclass extends self::Class {
+  synthetic constructor •() → self::Subclass
+    : super self::Class::•()
+    ;
+  method test() → void {
+    super.{self::Class::method}(0);
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart.weak.modular.expect
new file mode 100644
index 0000000..16ebb44
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart.weak.modular.expect
@@ -0,0 +1,179 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:41:7: Error: The non-abstract class 'ConcreteSub' is missing implementations for these members:
+//  - Interface1.extendedAbstractCovariantImplementedField
+//  - Interface1.extendedAbstractImplementedCovariantField
+//  - Interface1.implementsMultipleCovariantField1
+//  - Interface1.implementsMultipleCovariantField2
+//  - Interface2.implementsMultipleCovariantField1
+//  - Interface2.implementsMultipleCovariantField2
+//  - Super.extendedAbstractCovariantField
+//  - Super.extendedAbstractCovariantField=
+//  - Super.extendedAbstractCovariantImplementedField
+//  - Super.extendedAbstractCovariantImplementedField=
+//  - Super.extendedAbstractImplementedCovariantField
+//  - Super.extendedAbstractImplementedCovariantField=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSub extends AbstractClass {}
+//       ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:22:7: Context: 'Interface1.extendedAbstractCovariantImplementedField' is defined here.
+//   int extendedAbstractCovariantImplementedField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:26:17: Context: 'Interface1.extendedAbstractImplementedCovariantField' is defined here.
+//   covariant int extendedAbstractImplementedCovariantField = 0;
+//                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:28:17: Context: 'Interface1.implementsMultipleCovariantField1' is defined here.
+//   covariant int implementsMultipleCovariantField1 = 0;
+//                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:30:7: Context: 'Interface1.implementsMultipleCovariantField2' is defined here.
+//   int implementsMultipleCovariantField2 = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:34:7: Context: 'Interface2.implementsMultipleCovariantField1' is defined here.
+//   int implementsMultipleCovariantField1 = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:36:17: Context: 'Interface2.implementsMultipleCovariantField2' is defined here.
+//   covariant int implementsMultipleCovariantField2 = 0;
+//                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:8:26: Context: 'Super.extendedAbstractCovariantField' is defined here.
+//   abstract covariant int extendedAbstractCovariantField;
+//                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:8:26: Context: 'Super.extendedAbstractCovariantField=' is defined here.
+//   abstract covariant int extendedAbstractCovariantField;
+//                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:12:26: Context: 'Super.extendedAbstractCovariantImplementedField' is defined here.
+//   abstract covariant int extendedAbstractCovariantImplementedField;
+//                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:12:26: Context: 'Super.extendedAbstractCovariantImplementedField=' is defined here.
+//   abstract covariant int extendedAbstractCovariantImplementedField;
+//                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:16:16: Context: 'Super.extendedAbstractImplementedCovariantField' is defined here.
+//   abstract int extendedAbstractImplementedCovariantField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:16:16: Context: 'Super.extendedAbstractImplementedCovariantField=' is defined here.
+//   abstract int extendedAbstractImplementedCovariantField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:43:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - Interface1.extendedAbstractCovariantImplementedField
+//  - Interface1.extendedAbstractImplementedCovariantField
+//  - Interface1.implementsMultipleCovariantField1
+//  - Interface1.implementsMultipleCovariantField2
+//  - Interface2.implementsMultipleCovariantField1
+//  - Interface2.implementsMultipleCovariantField2
+//  - Super.extendedAbstractCovariantField
+//  - Super.extendedAbstractCovariantField=
+//  - Super.extendedAbstractCovariantImplementedField
+//  - Super.extendedAbstractCovariantImplementedField=
+//  - Super.extendedAbstractImplementedCovariantField
+//  - Super.extendedAbstractImplementedCovariantField=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass extends Super implements Interface1, Interface2 {}
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:22:7: Context: 'Interface1.extendedAbstractCovariantImplementedField' is defined here.
+//   int extendedAbstractCovariantImplementedField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:26:17: Context: 'Interface1.extendedAbstractImplementedCovariantField' is defined here.
+//   covariant int extendedAbstractImplementedCovariantField = 0;
+//                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:28:17: Context: 'Interface1.implementsMultipleCovariantField1' is defined here.
+//   covariant int implementsMultipleCovariantField1 = 0;
+//                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:30:7: Context: 'Interface1.implementsMultipleCovariantField2' is defined here.
+//   int implementsMultipleCovariantField2 = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:34:7: Context: 'Interface2.implementsMultipleCovariantField1' is defined here.
+//   int implementsMultipleCovariantField1 = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:36:17: Context: 'Interface2.implementsMultipleCovariantField2' is defined here.
+//   covariant int implementsMultipleCovariantField2 = 0;
+//                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:8:26: Context: 'Super.extendedAbstractCovariantField' is defined here.
+//   abstract covariant int extendedAbstractCovariantField;
+//                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:8:26: Context: 'Super.extendedAbstractCovariantField=' is defined here.
+//   abstract covariant int extendedAbstractCovariantField;
+//                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:12:26: Context: 'Super.extendedAbstractCovariantImplementedField' is defined here.
+//   abstract covariant int extendedAbstractCovariantImplementedField;
+//                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:12:26: Context: 'Super.extendedAbstractCovariantImplementedField=' is defined here.
+//   abstract covariant int extendedAbstractCovariantImplementedField;
+//                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:16:16: Context: 'Super.extendedAbstractImplementedCovariantField' is defined here.
+//   abstract int extendedAbstractImplementedCovariantField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_field.dart:16:16: Context: 'Super.extendedAbstractImplementedCovariantField=' is defined here.
+//   abstract int extendedAbstractImplementedCovariantField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Super extends core::Object {
+  covariant-by-declaration field core::int extendedConcreteCovariantField = 0;
+  covariant-by-declaration field core::int extendedConcreteCovariantImplementedField = 0;
+  field core::int extendedConcreteImplementedCovariantField = 0;
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  abstract get extendedAbstractCovariantField() → core::int;
+  abstract set extendedAbstractCovariantField(covariant-by-declaration core::int #externalFieldValue) → void;
+  abstract get extendedAbstractCovariantImplementedField() → core::int;
+  abstract set extendedAbstractCovariantImplementedField(covariant-by-declaration core::int #externalFieldValue) → void;
+  abstract get extendedAbstractImplementedCovariantField() → core::int;
+  abstract set extendedAbstractImplementedCovariantField(core::int #externalFieldValue) → void;
+}
+class Interface1 extends core::Object {
+  field core::int extendedConcreteCovariantImplementedField = 0;
+  field core::int extendedAbstractCovariantImplementedField = 0;
+  covariant-by-declaration field core::int extendedConcreteImplementedCovariantField = 0;
+  covariant-by-declaration field core::int extendedAbstractImplementedCovariantField = 0;
+  covariant-by-declaration field core::int implementsMultipleCovariantField1 = 0;
+  field core::int implementsMultipleCovariantField2 = 0;
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+}
+class Interface2 extends core::Object {
+  field core::int implementsMultipleCovariantField1 = 0;
+  covariant-by-declaration field core::int implementsMultipleCovariantField2 = 0;
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+}
+abstract class AbstractClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::AbstractClass
+    : super self::Super::•()
+    ;
+  forwarding-stub set extendedConcreteImplementedCovariantField(covariant-by-declaration core::int value) → void
+    return super.{self::Super::extendedConcreteImplementedCovariantField} = value;
+  abstract forwarding-stub set extendedAbstractImplementedCovariantField(covariant-by-declaration core::int #externalFieldValue) → void;
+  abstract forwarding-stub set implementsMultipleCovariantField2(covariant-by-declaration core::int value) → void;
+}
+class ConcreteSub extends self::AbstractClass {
+  synthetic constructor •() → self::ConcreteSub
+    : super self::AbstractClass::•()
+    ;
+}
+class ConcreteClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::ConcreteClass
+    : super self::Super::•()
+    ;
+  forwarding-stub set extendedConcreteImplementedCovariantField(covariant-by-declaration core::int value) → void
+    return super.{self::Super::extendedConcreteImplementedCovariantField} = value;
+  abstract forwarding-stub set extendedAbstractImplementedCovariantField(covariant-by-declaration core::int #externalFieldValue) → void;
+  abstract forwarding-stub set implementsMultipleCovariantField2(covariant-by-declaration core::int value) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart.weak.modular.expect
new file mode 100644
index 0000000..c62e3f2
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart.weak.modular.expect
@@ -0,0 +1,152 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:41:7: Error: The non-abstract class 'ConcreteSub' is missing implementations for these members:
+//  - Interface1.extendedAbstractCovariantImplementedMethod
+//  - Interface1.extendedAbstractImplementedCovariantMethod
+//  - Interface1.implementsMultipleCovariantMethod1
+//  - Interface1.implementsMultipleCovariantMethod2
+//  - Interface2.implementsMultipleCovariantMethod1
+//  - Interface2.implementsMultipleCovariantMethod2
+//  - Super.extendedAbstractCovariantImplementedMethod
+//  - Super.extendedAbstractCovariantMethod
+//  - Super.extendedAbstractImplementedCovariantMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSub extends AbstractClass {}
+//       ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:22:8: Context: 'Interface1.extendedAbstractCovariantImplementedMethod' is defined here.
+//   void extendedAbstractCovariantImplementedMethod(int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:26:8: Context: 'Interface1.extendedAbstractImplementedCovariantMethod' is defined here.
+//   void extendedAbstractImplementedCovariantMethod(covariant int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:28:8: Context: 'Interface1.implementsMultipleCovariantMethod1' is defined here.
+//   void implementsMultipleCovariantMethod1(covariant int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:30:8: Context: 'Interface1.implementsMultipleCovariantMethod2' is defined here.
+//   void implementsMultipleCovariantMethod2(int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:34:8: Context: 'Interface2.implementsMultipleCovariantMethod1' is defined here.
+//   void implementsMultipleCovariantMethod1(int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:36:8: Context: 'Interface2.implementsMultipleCovariantMethod2' is defined here.
+//   void implementsMultipleCovariantMethod2(covariant int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:12:8: Context: 'Super.extendedAbstractCovariantImplementedMethod' is defined here.
+//   void extendedAbstractCovariantImplementedMethod(covariant int i);
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:8:8: Context: 'Super.extendedAbstractCovariantMethod' is defined here.
+//   void extendedAbstractCovariantMethod(covariant int i);
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:16:8: Context: 'Super.extendedAbstractImplementedCovariantMethod' is defined here.
+//   void extendedAbstractImplementedCovariantMethod(int i);
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:43:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - Interface1.extendedAbstractCovariantImplementedMethod
+//  - Interface1.extendedAbstractImplementedCovariantMethod
+//  - Interface1.implementsMultipleCovariantMethod1
+//  - Interface1.implementsMultipleCovariantMethod2
+//  - Interface2.implementsMultipleCovariantMethod1
+//  - Interface2.implementsMultipleCovariantMethod2
+//  - Super.extendedAbstractCovariantImplementedMethod
+//  - Super.extendedAbstractCovariantMethod
+//  - Super.extendedAbstractImplementedCovariantMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass extends Super implements Interface1, Interface2 {}
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:22:8: Context: 'Interface1.extendedAbstractCovariantImplementedMethod' is defined here.
+//   void extendedAbstractCovariantImplementedMethod(int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:26:8: Context: 'Interface1.extendedAbstractImplementedCovariantMethod' is defined here.
+//   void extendedAbstractImplementedCovariantMethod(covariant int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:28:8: Context: 'Interface1.implementsMultipleCovariantMethod1' is defined here.
+//   void implementsMultipleCovariantMethod1(covariant int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:30:8: Context: 'Interface1.implementsMultipleCovariantMethod2' is defined here.
+//   void implementsMultipleCovariantMethod2(int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:34:8: Context: 'Interface2.implementsMultipleCovariantMethod1' is defined here.
+//   void implementsMultipleCovariantMethod1(int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:36:8: Context: 'Interface2.implementsMultipleCovariantMethod2' is defined here.
+//   void implementsMultipleCovariantMethod2(covariant int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:12:8: Context: 'Super.extendedAbstractCovariantImplementedMethod' is defined here.
+//   void extendedAbstractCovariantImplementedMethod(covariant int i);
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:8:8: Context: 'Super.extendedAbstractCovariantMethod' is defined here.
+//   void extendedAbstractCovariantMethod(covariant int i);
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_method.dart:16:8: Context: 'Super.extendedAbstractImplementedCovariantMethod' is defined here.
+//   void extendedAbstractImplementedCovariantMethod(int i);
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  method extendedConcreteCovariantMethod(covariant-by-declaration core::int i) → void {}
+  abstract method extendedAbstractCovariantMethod(covariant-by-declaration core::int i) → void;
+  method extendedConcreteCovariantImplementedMethod(covariant-by-declaration core::int i) → void {}
+  abstract method extendedAbstractCovariantImplementedMethod(covariant-by-declaration core::int i) → void;
+  method extendedConcreteImplementedCovariantMethod(core::int i) → void {}
+  abstract method extendedAbstractImplementedCovariantMethod(core::int i) → void;
+}
+class Interface1 extends core::Object {
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+  method extendedConcreteCovariantImplementedMethod(core::int i) → void {}
+  method extendedAbstractCovariantImplementedMethod(core::int i) → void {}
+  method extendedConcreteImplementedCovariantMethod(covariant-by-declaration core::int i) → void {}
+  method extendedAbstractImplementedCovariantMethod(covariant-by-declaration core::int i) → void {}
+  method implementsMultipleCovariantMethod1(covariant-by-declaration core::int i) → void {}
+  method implementsMultipleCovariantMethod2(core::int i) → void {}
+}
+class Interface2 extends core::Object {
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+  method implementsMultipleCovariantMethod1(core::int i) → void {}
+  method implementsMultipleCovariantMethod2(covariant-by-declaration core::int i) → void {}
+}
+abstract class AbstractClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::AbstractClass
+    : super self::Super::•()
+    ;
+  forwarding-stub method extendedConcreteImplementedCovariantMethod(covariant-by-declaration core::int i) → void
+    return super.{self::Super::extendedConcreteImplementedCovariantMethod}(i);
+  abstract forwarding-stub method extendedAbstractImplementedCovariantMethod(covariant-by-declaration core::int i) → void;
+  abstract forwarding-stub method implementsMultipleCovariantMethod2(covariant-by-declaration core::int i) → void;
+}
+class ConcreteSub extends self::AbstractClass {
+  synthetic constructor •() → self::ConcreteSub
+    : super self::AbstractClass::•()
+    ;
+}
+class ConcreteClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::ConcreteClass
+    : super self::Super::•()
+    ;
+  forwarding-stub method extendedConcreteImplementedCovariantMethod(covariant-by-declaration core::int i) → void
+    return super.{self::Super::extendedConcreteImplementedCovariantMethod}(i);
+  abstract forwarding-stub method extendedAbstractImplementedCovariantMethod(covariant-by-declaration core::int i) → void;
+  abstract forwarding-stub method implementsMultipleCovariantMethod2(covariant-by-declaration core::int i) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..ac74f0f
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart.weak.modular.expect
@@ -0,0 +1,152 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:41:7: Error: The non-abstract class 'ConcreteSub' is missing implementations for these members:
+//  - Interface1.extendedAbstractCovariantImplementedSetter=
+//  - Interface1.extendedAbstractImplementedCovariantSetter=
+//  - Interface1.implementsMultipleCovariantSetter1=
+//  - Interface1.implementsMultipleCovariantSetter2=
+//  - Interface2.implementsMultipleCovariantSetter1=
+//  - Interface2.implementsMultipleCovariantSetter2=
+//  - Super.extendedAbstractCovariantImplementedSetter=
+//  - Super.extendedAbstractCovariantSetter=
+//  - Super.extendedAbstractImplementedCovariantSetter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSub extends AbstractClass {}
+//       ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:22:12: Context: 'Interface1.extendedAbstractCovariantImplementedSetter=' is defined here.
+//   void set extendedAbstractCovariantImplementedSetter(int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:26:12: Context: 'Interface1.extendedAbstractImplementedCovariantSetter=' is defined here.
+//   void set extendedAbstractImplementedCovariantSetter(covariant int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:28:12: Context: 'Interface1.implementsMultipleCovariantSetter1=' is defined here.
+//   void set implementsMultipleCovariantSetter1(covariant int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:30:12: Context: 'Interface1.implementsMultipleCovariantSetter2=' is defined here.
+//   void set implementsMultipleCovariantSetter2(int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:34:12: Context: 'Interface2.implementsMultipleCovariantSetter1=' is defined here.
+//   void set implementsMultipleCovariantSetter1(int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:36:12: Context: 'Interface2.implementsMultipleCovariantSetter2=' is defined here.
+//   void set implementsMultipleCovariantSetter2(covariant int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:12:12: Context: 'Super.extendedAbstractCovariantImplementedSetter=' is defined here.
+//   void set extendedAbstractCovariantImplementedSetter(covariant int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:8:12: Context: 'Super.extendedAbstractCovariantSetter=' is defined here.
+//   void set extendedAbstractCovariantSetter(covariant int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:16:12: Context: 'Super.extendedAbstractImplementedCovariantSetter=' is defined here.
+//   void set extendedAbstractImplementedCovariantSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:43:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - Interface1.extendedAbstractCovariantImplementedSetter=
+//  - Interface1.extendedAbstractImplementedCovariantSetter=
+//  - Interface1.implementsMultipleCovariantSetter1=
+//  - Interface1.implementsMultipleCovariantSetter2=
+//  - Interface2.implementsMultipleCovariantSetter1=
+//  - Interface2.implementsMultipleCovariantSetter2=
+//  - Super.extendedAbstractCovariantImplementedSetter=
+//  - Super.extendedAbstractCovariantSetter=
+//  - Super.extendedAbstractImplementedCovariantSetter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass extends Super implements Interface1, Interface2 {}
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:22:12: Context: 'Interface1.extendedAbstractCovariantImplementedSetter=' is defined here.
+//   void set extendedAbstractCovariantImplementedSetter(int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:26:12: Context: 'Interface1.extendedAbstractImplementedCovariantSetter=' is defined here.
+//   void set extendedAbstractImplementedCovariantSetter(covariant int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:28:12: Context: 'Interface1.implementsMultipleCovariantSetter1=' is defined here.
+//   void set implementsMultipleCovariantSetter1(covariant int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:30:12: Context: 'Interface1.implementsMultipleCovariantSetter2=' is defined here.
+//   void set implementsMultipleCovariantSetter2(int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:34:12: Context: 'Interface2.implementsMultipleCovariantSetter1=' is defined here.
+//   void set implementsMultipleCovariantSetter1(int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:36:12: Context: 'Interface2.implementsMultipleCovariantSetter2=' is defined here.
+//   void set implementsMultipleCovariantSetter2(covariant int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:12:12: Context: 'Super.extendedAbstractCovariantImplementedSetter=' is defined here.
+//   void set extendedAbstractCovariantImplementedSetter(covariant int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:8:12: Context: 'Super.extendedAbstractCovariantSetter=' is defined here.
+//   void set extendedAbstractCovariantSetter(covariant int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/forwarding_stubs_setter.dart:16:12: Context: 'Super.extendedAbstractImplementedCovariantSetter=' is defined here.
+//   void set extendedAbstractImplementedCovariantSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  set extendedConcreteCovariantSetter(covariant-by-declaration core::int i) → void {}
+  abstract set extendedAbstractCovariantSetter(covariant-by-declaration core::int i) → void;
+  set extendedConcreteCovariantImplementedSetter(covariant-by-declaration core::int i) → void {}
+  abstract set extendedAbstractCovariantImplementedSetter(covariant-by-declaration core::int i) → void;
+  set extendedConcreteImplementedCovariantSetter(core::int i) → void {}
+  abstract set extendedAbstractImplementedCovariantSetter(core::int i) → void;
+}
+class Interface1 extends core::Object {
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+  set extendedConcreteCovariantImplementedSetter(core::int i) → void {}
+  set extendedAbstractCovariantImplementedSetter(core::int i) → void {}
+  set extendedConcreteImplementedCovariantSetter(covariant-by-declaration core::int i) → void {}
+  set extendedAbstractImplementedCovariantSetter(covariant-by-declaration core::int i) → void {}
+  set implementsMultipleCovariantSetter1(covariant-by-declaration core::int i) → void {}
+  set implementsMultipleCovariantSetter2(core::int i) → void {}
+}
+class Interface2 extends core::Object {
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+  set implementsMultipleCovariantSetter1(core::int i) → void {}
+  set implementsMultipleCovariantSetter2(covariant-by-declaration core::int i) → void {}
+}
+abstract class AbstractClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::AbstractClass
+    : super self::Super::•()
+    ;
+  forwarding-stub set extendedConcreteImplementedCovariantSetter(covariant-by-declaration core::int i) → void
+    return super.{self::Super::extendedConcreteImplementedCovariantSetter} = i;
+  abstract forwarding-stub set extendedAbstractImplementedCovariantSetter(covariant-by-declaration core::int i) → void;
+  abstract forwarding-stub set implementsMultipleCovariantSetter2(covariant-by-declaration core::int i) → void;
+}
+class ConcreteSub extends self::AbstractClass {
+  synthetic constructor •() → self::ConcreteSub
+    : super self::AbstractClass::•()
+    ;
+}
+class ConcreteClass extends self::Super implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::ConcreteClass
+    : super self::Super::•()
+    ;
+  forwarding-stub set extendedConcreteImplementedCovariantSetter(covariant-by-declaration core::int i) → void
+    return super.{self::Super::extendedConcreteImplementedCovariantSetter} = i;
+  abstract forwarding-stub set extendedAbstractImplementedCovariantSetter(covariant-by-declaration core::int i) → void;
+  abstract forwarding-stub set implementsMultipleCovariantSetter2(covariant-by-declaration core::int i) → void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..894fe23
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart.weak.modular.expect
@@ -0,0 +1,550 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the getter 'Super with Mixin.extendedSetterMixedInField' is not a subtype of the type 'int' of the inherited setter 'Super.extendedSetterMixedInField'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:19:12: Context: This is the declaration of the setter 'Super.extendedSetterMixedInField'.
+//   void set extendedSetterMixedInField(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the getter 'Super with Mixin.extendedSetterMixedInGetter' is not a subtype of the type 'int' of the inherited setter 'Super.extendedSetterMixedInGetter'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:23:12: Context: This is the declaration of the setter 'Super.extendedSetterMixedInGetter'.
+//   void set extendedSetterMixedInGetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited getter 'Super.extendedGetterMixedInSetter' is not a subtype of the type 'int' of the setter 'Super with Mixin.extendedGetterMixedInSetter'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:11:14: Context: This is the declaration of the getter 'Super.extendedGetterMixedInSetter'.
+//   String get extendedGetterMixedInSetter => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited field 'Super.extendedFieldMixedInSetter' is not a subtype of the type 'int' of the setter 'Super with Mixin.extendedFieldMixedInSetter'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:15:16: Context: This is the declaration of the field 'Super.extendedFieldMixedInSetter'.
+//   final String extendedFieldMixedInSetter = '';
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: Applying the mixin 'Mixin' to 'Super' introduces an erroneous override of 'extendedGetterMixedInField'.
+// abstract class Class extends Super
+//                ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:28:7: Context: The return type of the method 'Mixin.extendedGetterMixedInField' is 'int', which does not match the return type, 'String', of the overridden method, 'Super.extendedGetterMixedInField'.
+// Change to a subtype of 'String'.
+//   int extendedGetterMixedInField = 0;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:7:14: Context: This is the overridden method ('extendedGetterMixedInField').
+//   String get extendedGetterMixedInField => '';
+//              ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:93:16: Error: The type 'String' of the field 'Class.extendedSetterDeclaredField' is not a subtype of the type 'int' of the inherited setter 'Super.extendedSetterDeclaredField'.
+//   final String extendedSetterDeclaredField = '';
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:18:12: Context: This is the declaration of the setter 'Super.extendedSetterDeclaredField'.
+//   void set extendedSetterDeclaredField(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:94:14: Error: The type 'String' of the getter 'Class.extendedSetterDeclaredGetter' is not a subtype of the type 'int' of the inherited setter 'Super.extendedSetterDeclaredGetter'.
+//   String get extendedSetterDeclaredGetter => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:22:12: Context: This is the declaration of the setter 'Super.extendedSetterDeclaredGetter'.
+//   void set extendedSetterDeclaredGetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:99:16: Error: The type 'String' of the field 'Class.mixedInSetterDeclaredField' is not a subtype of the type 'int' of the inherited setter 'Super with Mixin.mixedInSetterDeclaredField'.
+//   final String mixedInSetterDeclaredField = '';
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Context: This is the declaration of the setter 'Super with Mixin.mixedInSetterDeclaredField'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:100:14: Error: The type 'String' of the getter 'Class.mixedInSetterDeclaredGetter' is not a subtype of the type 'int' of the inherited setter 'Super with Mixin.mixedInSetterDeclaredGetter'.
+//   String get mixedInSetterDeclaredGetter => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Context: This is the declaration of the setter 'Super with Mixin.mixedInSetterDeclaredGetter'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:105:16: Error: The type 'String' of the field 'Class.implementedSetterDeclaredField' is not a subtype of the type 'int' of the inherited setter 'Interface1.implementedSetterDeclaredField'.
+//   final String implementedSetterDeclaredField = '';
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:72:12: Context: This is the declaration of the setter 'Interface1.implementedSetterDeclaredField'.
+//   void set implementedSetterDeclaredField(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:106:14: Error: The type 'String' of the getter 'Class.implementedSetterDeclaredGetter' is not a subtype of the type 'int' of the inherited setter 'Interface1.implementedSetterDeclaredGetter'.
+//   String get implementedSetterDeclaredGetter => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:75:12: Context: This is the declaration of the setter 'Interface1.implementedSetterDeclaredGetter'.
+//   void set implementedSetterDeclaredGetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:108:14: Error: The type 'String' of the getter 'Class.declaredGetterDeclaredSetter' is not a subtype of the type 'int' of the setter 'Class.declaredGetterDeclaredSetter'.
+//   String get declaredGetterDeclaredSetter => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:109:12: Context: This is the declaration of the setter 'Class.declaredGetterDeclaredSetter'.
+//   void set declaredGetterDeclaredSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:111:16: Error: The type 'String' of the getter 'Class.declaredFieldDeclaredSetter' is not a subtype of the type 'int' of the setter 'Class.declaredFieldDeclaredSetter'.
+//   final String declaredFieldDeclaredSetter = '';
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:112:12: Context: This is the declaration of the setter 'Class.declaredFieldDeclaredSetter'.
+//   void set declaredFieldDeclaredSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:91:12: Error: The type 'String' of the inherited getter 'Super.extendedGetterDeclaredSetter' is not a subtype of the type 'int' of the setter 'Class.extendedGetterDeclaredSetter'.
+//   void set extendedGetterDeclaredSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:10:14: Context: This is the declaration of the getter 'Super.extendedGetterDeclaredSetter'.
+//   String get extendedGetterDeclaredSetter => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:92:12: Error: The type 'String' of the inherited field 'Super.extendedFieldDeclaredSetter' is not a subtype of the type 'int' of the setter 'Class.extendedFieldDeclaredSetter'.
+//   void set extendedFieldDeclaredSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:14:16: Context: This is the declaration of the field 'Super.extendedFieldDeclaredSetter'.
+//   final String extendedFieldDeclaredSetter = '';
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:97:12: Error: The type 'String' of the inherited getter 'Super with Mixin.mixedInGetterDeclaredSetter' is not a subtype of the type 'int' of the setter 'Class.mixedInGetterDeclaredSetter'.
+//   void set mixedInGetterDeclaredSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Context: This is the declaration of the getter 'Super with Mixin.mixedInGetterDeclaredSetter'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:98:12: Error: The type 'String' of the inherited getter 'Super with Mixin.mixedInFieldDeclaredSetter' is not a subtype of the type 'int' of the setter 'Class.mixedInFieldDeclaredSetter'.
+//   void set mixedInFieldDeclaredSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Context: This is the declaration of the getter 'Super with Mixin.mixedInFieldDeclaredSetter'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:103:12: Error: The type 'String' of the inherited getter 'Interface1.implementedGetterDeclaredSetter' is not a subtype of the type 'int' of the setter 'Class.implementedGetterDeclaredSetter'.
+//   void set implementedGetterDeclaredSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:66:14: Context: This is the declaration of the getter 'Interface1.implementedGetterDeclaredSetter'.
+//   String get implementedGetterDeclaredSetter => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:104:12: Error: The type 'String' of the inherited field 'Interface1.implementedFieldDeclaredSetter' is not a subtype of the type 'int' of the setter 'Class.implementedFieldDeclaredSetter'.
+//   void set implementedFieldDeclaredSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:69:16: Context: This is the declaration of the field 'Interface1.implementedFieldDeclaredSetter'.
+//   final String implementedFieldDeclaredSetter = '';
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited getter 'Super with Mixin.extendedSetterMixedInField' is not a subtype of the type 'int' of the inherited setter 'Super.extendedSetterMixedInField'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Context: This is the declaration of the getter 'Super with Mixin.extendedSetterMixedInField'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:19:12: Context: This is the declaration of the setter 'Super.extendedSetterMixedInField'.
+//   void set extendedSetterMixedInField(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited getter 'Super with Mixin.extendedSetterMixedInGetter' is not a subtype of the type 'int' of the inherited setter 'Super.extendedSetterMixedInGetter'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Context: This is the declaration of the getter 'Super with Mixin.extendedSetterMixedInGetter'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:23:12: Context: This is the declaration of the setter 'Super.extendedSetterMixedInGetter'.
+//   void set extendedSetterMixedInGetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: Class 'Class' inherits multiple members named 'Mixin.mixedInGetterImplementedField' with incompatible signatures.
+// Try adding a declaration of 'Mixin.mixedInGetterImplementedField' to 'Class'.
+// abstract class Class extends Super
+//                ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:35:14: Context: This is one of the overridden members.
+//   String get mixedInGetterImplementedField => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:57:7: Context: This is one of the overridden members.
+//   int mixedInGetterImplementedField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited getter 'Super with Mixin.mixedInGetterImplementedField' is not a subtype of the type 'int' of the inherited setter 'Interface1.mixedInGetterImplementedField'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Context: This is the declaration of the getter 'Super with Mixin.mixedInGetterImplementedField'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:57:7: Context: This is the declaration of the setter 'Interface1.mixedInGetterImplementedField'.
+//   int mixedInGetterImplementedField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited getter 'Super with Mixin.mixedInGetterImplementedSetter' is not a subtype of the type 'int' of the inherited setter 'Interface1.mixedInGetterImplementedSetter'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Context: This is the declaration of the getter 'Super with Mixin.mixedInGetterImplementedSetter'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:58:12: Context: This is the declaration of the setter 'Interface1.mixedInGetterImplementedSetter'.
+//   void set mixedInGetterImplementedSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited getter 'Super with Mixin.mixedInFieldImplementedSetter' is not a subtype of the type 'int' of the inherited setter 'Interface1.mixedInFieldImplementedSetter'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Context: This is the declaration of the getter 'Super with Mixin.mixedInFieldImplementedSetter'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:59:12: Context: This is the declaration of the setter 'Interface1.mixedInFieldImplementedSetter'.
+//   void set mixedInFieldImplementedSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited getter 'Super.extendedGetterMixedInSetter' is not a subtype of the type 'int' of the inherited setter 'Super with Mixin.extendedGetterMixedInSetter'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:11:14: Context: This is the declaration of the getter 'Super.extendedGetterMixedInSetter'.
+//   String get extendedGetterMixedInSetter => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Context: This is the declaration of the setter 'Super with Mixin.extendedGetterMixedInSetter'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited field 'Super.extendedFieldMixedInSetter' is not a subtype of the type 'int' of the inherited setter 'Super with Mixin.extendedFieldMixedInSetter'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:15:16: Context: This is the declaration of the field 'Super.extendedFieldMixedInSetter'.
+//   final String extendedFieldMixedInSetter = '';
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Context: This is the declaration of the setter 'Super with Mixin.extendedFieldMixedInSetter'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: Class 'Class' inherits multiple members named 'extendedGetterImplementedField' with incompatible signatures.
+// Try adding a declaration of 'extendedGetterImplementedField' to 'Class'.
+// abstract class Class extends Super
+//                ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:8:14: Context: This is one of the overridden members.
+//   String get extendedGetterImplementedField => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:51:7: Context: This is one of the overridden members.
+//   int extendedGetterImplementedField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited getter 'Super.extendedGetterImplementedField' is not a subtype of the type 'int' of the inherited setter 'Interface1.extendedGetterImplementedField'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:8:14: Context: This is the declaration of the getter 'Super.extendedGetterImplementedField'.
+//   String get extendedGetterImplementedField => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:51:7: Context: This is the declaration of the setter 'Interface1.extendedGetterImplementedField'.
+//   int extendedGetterImplementedField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited getter 'Super.extendedGetterImplementedSetter' is not a subtype of the type 'int' of the inherited setter 'Interface1.extendedGetterImplementedSetter'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:12:14: Context: This is the declaration of the getter 'Super.extendedGetterImplementedSetter'.
+//   String get extendedGetterImplementedSetter => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:52:12: Context: This is the declaration of the setter 'Interface1.extendedGetterImplementedSetter'.
+//   void set extendedGetterImplementedSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited field 'Super.extendedFieldImplementedSetter' is not a subtype of the type 'int' of the inherited setter 'Interface1.extendedFieldImplementedSetter'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:16:16: Context: This is the declaration of the field 'Super.extendedFieldImplementedSetter'.
+//   final String extendedFieldImplementedSetter = '';
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:53:12: Context: This is the declaration of the setter 'Interface1.extendedFieldImplementedSetter'.
+//   void set extendedFieldImplementedSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited field 'Interface1.mixedInSetterImplementedField' is not a subtype of the type 'int' of the inherited setter 'Super with Mixin.mixedInSetterImplementedField'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:60:16: Context: This is the declaration of the field 'Interface1.mixedInSetterImplementedField'.
+//   final String mixedInSetterImplementedField = '';
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Context: This is the declaration of the setter 'Super with Mixin.mixedInSetterImplementedField'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited getter 'Interface1.mixedInSetterImplementedGetter' is not a subtype of the type 'int' of the inherited setter 'Super with Mixin.mixedInSetterImplementedGetter'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:61:14: Context: This is the declaration of the getter 'Interface1.mixedInSetterImplementedGetter'.
+//   String get mixedInSetterImplementedGetter => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Context: This is the declaration of the setter 'Super with Mixin.mixedInSetterImplementedGetter'.
+// abstract class Class extends Super
+//                ^^^^^^^^^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited field 'Interface1.extendedSetterImplementedField' is not a subtype of the type 'int' of the inherited setter 'Super.extendedSetterImplementedField'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:54:16: Context: This is the declaration of the field 'Interface1.extendedSetterImplementedField'.
+//   final String extendedSetterImplementedField = '';
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:20:12: Context: This is the declaration of the setter 'Super.extendedSetterImplementedField'.
+//   void set extendedSetterImplementedField(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited getter 'Interface1.extendedSetterImplementedGetter' is not a subtype of the type 'int' of the inherited setter 'Super.extendedSetterImplementedGetter'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:55:14: Context: This is the declaration of the getter 'Interface1.extendedSetterImplementedGetter'.
+//   String get extendedSetterImplementedGetter => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:24:12: Context: This is the declaration of the setter 'Super.extendedSetterImplementedGetter'.
+//   void set extendedSetterImplementedGetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: Class 'Class' inherits multiple members named 'implementedGetterImplementedField' with incompatible signatures.
+// Try adding a declaration of 'implementedGetterImplementedField' to 'Class'.
+// abstract class Class extends Super
+//                ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:64:14: Context: This is one of the overridden members.
+//   String get implementedGetterImplementedField => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:80:7: Context: This is one of the overridden members.
+//   int implementedGetterImplementedField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited getter 'Interface1.implementedGetterImplementedField' is not a subtype of the type 'int' of the inherited setter 'Interface2.implementedGetterImplementedField'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:64:14: Context: This is the declaration of the getter 'Interface1.implementedGetterImplementedField'.
+//   String get implementedGetterImplementedField => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:80:7: Context: This is the declaration of the setter 'Interface2.implementedGetterImplementedField'.
+//   int implementedGetterImplementedField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited getter 'Interface1.implementedGetterImplementedSetter' is not a subtype of the type 'int' of the inherited setter 'Interface2.implementedGetterImplementedSetter'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:67:14: Context: This is the declaration of the getter 'Interface1.implementedGetterImplementedSetter'.
+//   String get implementedGetterImplementedSetter => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:81:12: Context: This is the declaration of the setter 'Interface2.implementedGetterImplementedSetter'.
+//   void set implementedGetterImplementedSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited field 'Interface1.implementedFieldImplementedSetter' is not a subtype of the type 'int' of the inherited setter 'Interface2.implementedFieldImplementedSetter'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:70:16: Context: This is the declaration of the field 'Interface1.implementedFieldImplementedSetter'.
+//   final String implementedFieldImplementedSetter = '';
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:82:12: Context: This is the declaration of the setter 'Interface2.implementedFieldImplementedSetter'.
+//   void set implementedFieldImplementedSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited field 'Interface2.implementedSetterImplementedField' is not a subtype of the type 'int' of the inherited setter 'Interface1.implementedSetterImplementedField'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:83:16: Context: This is the declaration of the field 'Interface2.implementedSetterImplementedField'.
+//   final String implementedSetterImplementedField = '';
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:73:12: Context: This is the declaration of the setter 'Interface1.implementedSetterImplementedField'.
+//   void set implementedSetterImplementedField(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Error: The type 'String' of the inherited getter 'Interface2.implementedSetterImplementedGetter' is not a subtype of the type 'int' of the inherited setter 'Interface1.implementedSetterImplementedGetter'.
+// abstract class Class extends Super
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:84:14: Context: This is the declaration of the getter 'Interface2.implementedSetterImplementedGetter'.
+//   String get implementedSetterImplementedGetter => '';
+//              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:76:12: Context: This is the declaration of the setter 'Interface1.implementedSetterImplementedGetter'.
+//   void set implementedSetterImplementedGetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:90:7: Error: The return type of the method 'Class.extendedGetterDeclaredField' is 'int', which does not match the return type, 'String', of the overridden method, 'Super.extendedGetterDeclaredField'.
+// Change to a subtype of 'String'.
+//   int extendedGetterDeclaredField = 0;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:6:14: Context: This is the overridden method ('extendedGetterDeclaredField').
+//   String get extendedGetterDeclaredField => '';
+//              ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:96:7: Error: The return type of the method 'Class.mixedInGetterDeclaredField' is 'int', which does not match the return type, 'String', of the overridden method, 'Super with Mixin.mixedInGetterDeclaredField'.
+// Change to a subtype of 'String'.
+//   int mixedInGetterDeclaredField = 0;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:87:16: Context: This is the overridden method ('mixedInGetterDeclaredField').
+// abstract class Class extends Super
+//                ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:102:7: Error: The return type of the method 'Class.implementedGetterDeclaredField' is 'int', which does not match the return type, 'String', of the overridden method, 'Interface1.implementedGetterDeclaredField'.
+// Change to a subtype of 'String'.
+//   int implementedGetterDeclaredField = 0;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/getter_setter.dart:63:14: Context: This is the overridden method ('implementedGetterDeclaredField').
+//   String get implementedGetterDeclaredField => '';
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Super extends core::Object {
+  final field core::String extendedFieldDeclaredSetter = "";
+  final field core::String extendedFieldMixedInSetter = "";
+  final field core::String extendedFieldImplementedSetter = "";
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  get extendedGetterDeclaredField() → core::String
+    return "";
+  get extendedGetterMixedInField() → core::String
+    return "";
+  get extendedGetterImplementedField() → core::String
+    return "";
+  get extendedGetterDeclaredSetter() → core::String
+    return "";
+  get extendedGetterMixedInSetter() → core::String
+    return "";
+  get extendedGetterImplementedSetter() → core::String
+    return "";
+  set extendedSetterDeclaredField(core::int value) → void {}
+  set extendedSetterMixedInField(core::int value) → void {}
+  set extendedSetterImplementedField(core::int value) → void {}
+  set extendedSetterDeclaredGetter(core::int value) → void {}
+  set extendedSetterMixedInGetter(core::int value) → void {}
+  set extendedSetterImplementedGetter(core::int value) → void {}
+}
+abstract class Mixin extends core::Object {
+  field core::int extendedGetterMixedInField = 0;
+  final field core::String extendedSetterMixedInField = "";
+  final field core::String mixedInFieldDeclaredSetter = "";
+  final field core::String mixedInFieldImplementedSetter = "";
+  synthetic constructor •() → self::Mixin
+    : super core::Object::•()
+    ;
+  set extendedGetterMixedInSetter(core::int value) → void {}
+  set extendedFieldMixedInSetter(core::int value) → void {}
+  get extendedSetterMixedInGetter() → core::String
+    return "";
+  get mixedInGetterDeclaredField() → core::String
+    return "";
+  get mixedInGetterImplementedField() → core::String
+    return "";
+  get mixedInGetterDeclaredSetter() → core::String
+    return "";
+  get mixedInGetterImplementedSetter() → core::String
+    return "";
+  set mixedInSetterDeclaredField(core::int value) → void {}
+  set mixedInSetterImplementedField(core::int value) → void {}
+  set mixedInSetterDeclaredGetter(core::int value) → void {}
+  set mixedInSetterImplementedGetter(core::int value) → void {}
+}
+abstract class Interface1 extends core::Object {
+  field core::int extendedGetterImplementedField = 0;
+  final field core::String extendedSetterImplementedField = "";
+  field core::int mixedInGetterImplementedField = 0;
+  final field core::String mixedInSetterImplementedField = "";
+  final field core::String implementedFieldDeclaredSetter = "";
+  final field core::String implementedFieldImplementedSetter = "";
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+  set extendedGetterImplementedSetter(core::int value) → void {}
+  set extendedFieldImplementedSetter(core::int value) → void {}
+  get extendedSetterImplementedGetter() → core::String
+    return "";
+  set mixedInGetterImplementedSetter(core::int value) → void {}
+  set mixedInFieldImplementedSetter(core::int value) → void {}
+  get mixedInSetterImplementedGetter() → core::String
+    return "";
+  get implementedGetterDeclaredField() → core::String
+    return "";
+  get implementedGetterImplementedField() → core::String
+    return "";
+  get implementedGetterDeclaredSetter() → core::String
+    return "";
+  get implementedGetterImplementedSetter() → core::String
+    return "";
+  set implementedSetterDeclaredField(core::int value) → void {}
+  set implementedSetterImplementedField(core::int value) → void {}
+  set implementedSetterDeclaredGetter(core::int value) → void {}
+  set implementedSetterImplementedGetter(core::int value) → void {}
+}
+abstract class Interface2 extends core::Object {
+  field core::int implementedGetterImplementedField = 0;
+  final field core::String implementedSetterImplementedField = "";
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+  set implementedGetterImplementedSetter(core::int value) → void {}
+  set implementedFieldImplementedSetter(core::int value) → void {}
+  get implementedSetterImplementedGetter() → core::String
+    return "";
+}
+abstract class _Class&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&Mixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub get mixedInGetterDeclaredField() → core::String
+    return super.{self::Mixin::mixedInGetterDeclaredField};
+  mixin-super-stub set mixedInSetterDeclaredField(core::int value) → void
+    return super.{self::Mixin::mixedInSetterDeclaredField} = value;
+  mixin-super-stub get mixedInGetterDeclaredSetter() → core::String
+    return super.{self::Mixin::mixedInGetterDeclaredSetter};
+  mixin-super-stub get mixedInFieldDeclaredSetter() → core::String
+    return super.{self::Mixin::mixedInFieldDeclaredSetter};
+  mixin-super-stub get extendedGetterMixedInField() → core::int
+    return super.{self::Mixin::extendedGetterMixedInField};
+  mixin-super-stub set extendedGetterMixedInField(core::int value) → void
+    return super.{self::Mixin::extendedGetterMixedInField} = value;
+  mixin-super-stub get extendedSetterMixedInField() → core::String
+    return super.{self::Mixin::extendedSetterMixedInField};
+  mixin-super-stub get extendedSetterMixedInGetter() → core::String
+    return super.{self::Mixin::extendedSetterMixedInGetter};
+  mixin-super-stub set extendedGetterMixedInSetter(core::int value) → void
+    return super.{self::Mixin::extendedGetterMixedInSetter} = value;
+  mixin-super-stub set extendedFieldMixedInSetter(core::int value) → void
+    return super.{self::Mixin::extendedFieldMixedInSetter} = value;
+  mixin-super-stub set mixedInSetterDeclaredGetter(core::int value) → void
+    return super.{self::Mixin::mixedInSetterDeclaredGetter} = value;
+  mixin-super-stub get mixedInGetterImplementedField() → core::String
+    return super.{self::Mixin::mixedInGetterImplementedField};
+  mixin-super-stub get mixedInGetterImplementedSetter() → core::String
+    return super.{self::Mixin::mixedInGetterImplementedSetter};
+  mixin-super-stub get mixedInFieldImplementedSetter() → core::String
+    return super.{self::Mixin::mixedInFieldImplementedSetter};
+  mixin-super-stub set mixedInSetterImplementedField(core::int value) → void
+    return super.{self::Mixin::mixedInSetterImplementedField} = value;
+  mixin-super-stub set mixedInSetterImplementedGetter(core::int value) → void
+    return super.{self::Mixin::mixedInSetterImplementedGetter} = value;
+}
+abstract class Class extends self::_Class&Super&Mixin implements self::Interface1, self::Interface2 {
+  field core::int extendedGetterDeclaredField = 0;
+  final field core::String extendedSetterDeclaredField = "";
+  field core::int mixedInGetterDeclaredField = 0;
+  final field core::String mixedInSetterDeclaredField = "";
+  field core::int implementedGetterDeclaredField = 0;
+  final field core::String implementedSetterDeclaredField = "";
+  final field core::String declaredFieldDeclaredSetter = "";
+  synthetic constructor •() → self::Class
+    : super self::_Class&Super&Mixin::•()
+    ;
+  set extendedGetterDeclaredSetter(core::int value) → void {}
+  set extendedFieldDeclaredSetter(core::int value) → void {}
+  get extendedSetterDeclaredGetter() → core::String
+    return "";
+  set mixedInGetterDeclaredSetter(core::int value) → void {}
+  set mixedInFieldDeclaredSetter(core::int value) → void {}
+  get mixedInSetterDeclaredGetter() → core::String
+    return "";
+  set implementedGetterDeclaredSetter(core::int value) → void {}
+  set implementedFieldDeclaredSetter(core::int value) → void {}
+  get implementedSetterDeclaredGetter() → core::String
+    return "";
+  get declaredGetterDeclaredSetter() → core::String
+    return "";
+  set declaredGetterDeclaredSetter(core::int value) → void {}
+  set declaredFieldDeclaredSetter(core::int value) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_field.dart.weak.modular.expect
new file mode 100644
index 0000000..4701040
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_field.dart.weak.modular.expect
@@ -0,0 +1,105 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_field.dart:21:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - ConcreteClass.declareAbstractImplementMultipleField
+//  - ConcreteClass.declareAbstractImplementMultipleField=
+//  - Interface1.implementMultipleField
+//  - Interface2.implementMultipleField
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass implements Interface1, Interface2 {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_field.dart:24:16: Context: 'ConcreteClass.declareAbstractImplementMultipleField' is defined here.
+//   abstract int declareAbstractImplementMultipleField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_field.dart:24:16: Context: 'ConcreteClass.declareAbstractImplementMultipleField=' is defined here.
+//   abstract int declareAbstractImplementMultipleField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_field.dart:6:7: Context: 'Interface1.implementMultipleField' is defined here.
+//   int implementMultipleField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_field.dart:14:7: Context: 'Interface2.implementMultipleField' is defined here.
+//   int implementMultipleField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_field.dart:33:7: Error: The non-abstract class 'ConcreteSub' is missing implementations for these members:
+//  - AbstractClass.declareAbstractImplementMultipleField
+//  - AbstractClass.declareAbstractImplementMultipleField=
+//  - Interface1.declareAbstractImplementMultipleField
+//  - Interface1.implementMultipleField
+//  - Interface2.declareAbstractImplementMultipleField
+//  - Interface2.implementMultipleField
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSub extends AbstractClass {}
+//       ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_field.dart:30:16: Context: 'AbstractClass.declareAbstractImplementMultipleField' is defined here.
+//   abstract int declareAbstractImplementMultipleField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_field.dart:30:16: Context: 'AbstractClass.declareAbstractImplementMultipleField=' is defined here.
+//   abstract int declareAbstractImplementMultipleField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_field.dart:10:7: Context: 'Interface1.declareAbstractImplementMultipleField' is defined here.
+//   int declareAbstractImplementMultipleField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_field.dart:6:7: Context: 'Interface1.implementMultipleField' is defined here.
+//   int implementMultipleField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_field.dart:18:7: Context: 'Interface2.declareAbstractImplementMultipleField' is defined here.
+//   int declareAbstractImplementMultipleField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_field.dart:14:7: Context: 'Interface2.implementMultipleField' is defined here.
+//   int implementMultipleField = 0;
+//       ^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Interface1 extends core::Object {
+  field core::int implementMultipleField = 0;
+  field core::int declareConcreteImplementMultipleField = 0;
+  field core::int declareAbstractImplementMultipleField = 0;
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+}
+class Interface2 extends core::Object {
+  field core::int implementMultipleField = 0;
+  field core::int declareConcreteImplementMultipleField = 0;
+  field core::int declareAbstractImplementMultipleField = 0;
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+}
+class ConcreteClass extends core::Object implements self::Interface1, self::Interface2 {
+  field core::int declareConcreteImplementMultipleField = 0;
+  synthetic constructor •() → self::ConcreteClass
+    : super core::Object::•()
+    ;
+  abstract get declareAbstractImplementMultipleField() → core::int;
+  abstract set declareAbstractImplementMultipleField(core::int #externalFieldValue) → void;
+}
+abstract class AbstractClass extends core::Object implements self::Interface1, self::Interface2 {
+  field core::int declareConcreteImplementMultipleField = 0;
+  synthetic constructor •() → self::AbstractClass
+    : super core::Object::•()
+    ;
+  abstract get declareAbstractImplementMultipleField() → core::int;
+  abstract set declareAbstractImplementMultipleField(core::int #externalFieldValue) → void;
+}
+class ConcreteSub extends self::AbstractClass {
+  synthetic constructor •() → self::ConcreteSub
+    : super self::AbstractClass::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_final_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_final_field.dart.weak.modular.expect
new file mode 100644
index 0000000..5ebd497f
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_final_field.dart.weak.modular.expect
@@ -0,0 +1,95 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_final_field.dart:21:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - ConcreteClass.declareAbstractImplementMultipleField
+//  - Interface1.implementMultipleField
+//  - Interface2.implementMultipleField
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass implements Interface1, Interface2 {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_final_field.dart:24:22: Context: 'ConcreteClass.declareAbstractImplementMultipleField' is defined here.
+//   abstract final int declareAbstractImplementMultipleField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_final_field.dart:6:13: Context: 'Interface1.implementMultipleField' is defined here.
+//   final int implementMultipleField = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_final_field.dart:14:13: Context: 'Interface2.implementMultipleField' is defined here.
+//   final int implementMultipleField = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_final_field.dart:33:7: Error: The non-abstract class 'ConcreteSub' is missing implementations for these members:
+//  - AbstractClass.declareAbstractImplementMultipleField
+//  - Interface1.declareAbstractImplementMultipleField
+//  - Interface1.implementMultipleField
+//  - Interface2.declareAbstractImplementMultipleField
+//  - Interface2.implementMultipleField
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSub extends AbstractClass {}
+//       ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_final_field.dart:30:22: Context: 'AbstractClass.declareAbstractImplementMultipleField' is defined here.
+//   abstract final int declareAbstractImplementMultipleField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_final_field.dart:10:13: Context: 'Interface1.declareAbstractImplementMultipleField' is defined here.
+//   final int declareAbstractImplementMultipleField = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_final_field.dart:6:13: Context: 'Interface1.implementMultipleField' is defined here.
+//   final int implementMultipleField = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_final_field.dart:18:13: Context: 'Interface2.declareAbstractImplementMultipleField' is defined here.
+//   final int declareAbstractImplementMultipleField = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_final_field.dart:14:13: Context: 'Interface2.implementMultipleField' is defined here.
+//   final int implementMultipleField = 0;
+//             ^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Interface1 extends core::Object {
+  final field core::int implementMultipleField = 0;
+  final field core::int declareConcreteImplementMultipleField = 0;
+  final field core::int declareAbstractImplementMultipleField = 0;
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+}
+class Interface2 extends core::Object {
+  final field core::int implementMultipleField = 0;
+  final field core::int declareConcreteImplementMultipleField = 0;
+  final field core::int declareAbstractImplementMultipleField = 0;
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+}
+class ConcreteClass extends core::Object implements self::Interface1, self::Interface2 {
+  final field core::int declareConcreteImplementMultipleField = 0;
+  synthetic constructor •() → self::ConcreteClass
+    : super core::Object::•()
+    ;
+  abstract get declareAbstractImplementMultipleField() → core::int;
+}
+abstract class AbstractClass extends core::Object implements self::Interface1, self::Interface2 {
+  final field core::int declareConcreteImplementMultipleField = 0;
+  synthetic constructor •() → self::AbstractClass
+    : super core::Object::•()
+    ;
+  abstract get declareAbstractImplementMultipleField() → core::int;
+}
+class ConcreteSub extends self::AbstractClass {
+  synthetic constructor •() → self::ConcreteSub
+    : super self::AbstractClass::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_getter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..538cee7
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_getter.dart.weak.modular.expect
@@ -0,0 +1,103 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_getter.dart:21:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - ConcreteClass.declareAbstractImplementMultipleGetter
+//  - Interface1.implementMultipleGetter
+//  - Interface2.implementMultipleGetter
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass implements Interface1, Interface2 {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_getter.dart:24:11: Context: 'ConcreteClass.declareAbstractImplementMultipleGetter' is defined here.
+//   int get declareAbstractImplementMultipleGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_getter.dart:6:11: Context: 'Interface1.implementMultipleGetter' is defined here.
+//   int get implementMultipleGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_getter.dart:14:11: Context: 'Interface2.implementMultipleGetter' is defined here.
+//   int get implementMultipleGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_getter.dart:33:7: Error: The non-abstract class 'ConcreteSub' is missing implementations for these members:
+//  - AbstractClass.declareAbstractImplementMultipleGetter
+//  - Interface1.declareAbstractImplementMultipleGetter
+//  - Interface1.implementMultipleGetter
+//  - Interface2.declareAbstractImplementMultipleGetter
+//  - Interface2.implementMultipleGetter
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSub extends AbstractClass {}
+//       ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_getter.dart:30:11: Context: 'AbstractClass.declareAbstractImplementMultipleGetter' is defined here.
+//   int get declareAbstractImplementMultipleGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_getter.dart:10:11: Context: 'Interface1.declareAbstractImplementMultipleGetter' is defined here.
+//   int get declareAbstractImplementMultipleGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_getter.dart:6:11: Context: 'Interface1.implementMultipleGetter' is defined here.
+//   int get implementMultipleGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_getter.dart:18:11: Context: 'Interface2.declareAbstractImplementMultipleGetter' is defined here.
+//   int get declareAbstractImplementMultipleGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_getter.dart:14:11: Context: 'Interface2.implementMultipleGetter' is defined here.
+//   int get implementMultipleGetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Interface1 extends core::Object {
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+  get implementMultipleGetter() → core::int
+    return 0;
+  get declareConcreteImplementMultipleGetter() → core::int
+    return 0;
+  get declareAbstractImplementMultipleGetter() → core::int
+    return 0;
+}
+class Interface2 extends core::Object {
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+  get implementMultipleGetter() → core::int
+    return 0;
+  get declareConcreteImplementMultipleGetter() → core::int
+    return 0;
+  get declareAbstractImplementMultipleGetter() → core::int
+    return 0;
+}
+class ConcreteClass extends core::Object implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::ConcreteClass
+    : super core::Object::•()
+    ;
+  get declareConcreteImplementMultipleGetter() → core::int
+    return 0;
+  abstract get declareAbstractImplementMultipleGetter() → core::int;
+}
+abstract class AbstractClass extends core::Object implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::AbstractClass
+    : super core::Object::•()
+    ;
+  get declareConcreteImplementMultipleGetter() → core::int
+    return 0;
+  abstract get declareAbstractImplementMultipleGetter() → core::int;
+}
+class ConcreteSub extends self::AbstractClass {
+  synthetic constructor •() → self::ConcreteSub
+    : super self::AbstractClass::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_method.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_method.dart.weak.modular.expect
new file mode 100644
index 0000000..66a5d5e
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_method.dart.weak.modular.expect
@@ -0,0 +1,95 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_method.dart:21:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - ConcreteClass.declareAbstractImplementMultipleMethod
+//  - Interface1.implementMultipleMethod
+//  - Interface2.implementMultipleMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass implements Interface1, Interface2 {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_method.dart:24:8: Context: 'ConcreteClass.declareAbstractImplementMultipleMethod' is defined here.
+//   void declareAbstractImplementMultipleMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_method.dart:6:8: Context: 'Interface1.implementMultipleMethod' is defined here.
+//   void implementMultipleMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_method.dart:14:8: Context: 'Interface2.implementMultipleMethod' is defined here.
+//   void implementMultipleMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_method.dart:33:7: Error: The non-abstract class 'ConcreteSub' is missing implementations for these members:
+//  - AbstractClass.declareAbstractImplementMultipleMethod
+//  - Interface1.declareAbstractImplementMultipleMethod
+//  - Interface1.implementMultipleMethod
+//  - Interface2.declareAbstractImplementMultipleMethod
+//  - Interface2.implementMultipleMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSub extends AbstractClass {}
+//       ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_method.dart:30:8: Context: 'AbstractClass.declareAbstractImplementMultipleMethod' is defined here.
+//   void declareAbstractImplementMultipleMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_method.dart:10:8: Context: 'Interface1.declareAbstractImplementMultipleMethod' is defined here.
+//   void declareAbstractImplementMultipleMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_method.dart:6:8: Context: 'Interface1.implementMultipleMethod' is defined here.
+//   void implementMultipleMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_method.dart:18:8: Context: 'Interface2.declareAbstractImplementMultipleMethod' is defined here.
+//   void declareAbstractImplementMultipleMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_method.dart:14:8: Context: 'Interface2.implementMultipleMethod' is defined here.
+//   void implementMultipleMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Interface1 extends core::Object {
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+  method implementMultipleMethod() → void {}
+  method declareConcreteImplementMultipleMethod() → void {}
+  method declareAbstractImplementMultipleMethod() → void {}
+}
+class Interface2 extends core::Object {
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+  method implementMultipleMethod() → void {}
+  method declareConcreteImplementMultipleMethod() → void {}
+  method declareAbstractImplementMultipleMethod() → void {}
+}
+class ConcreteClass extends core::Object implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::ConcreteClass
+    : super core::Object::•()
+    ;
+  method declareConcreteImplementMultipleMethod() → void {}
+  abstract method declareAbstractImplementMultipleMethod() → void;
+}
+abstract class AbstractClass extends core::Object implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::AbstractClass
+    : super core::Object::•()
+    ;
+  method declareConcreteImplementMultipleMethod() → void {}
+  abstract method declareAbstractImplementMultipleMethod() → void;
+}
+class ConcreteSub extends self::AbstractClass {
+  synthetic constructor •() → self::ConcreteSub
+    : super self::AbstractClass::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_setter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..c960de6
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_setter.dart.weak.modular.expect
@@ -0,0 +1,95 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_setter.dart:21:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - ConcreteClass.declareAbstractImplementMultipleSetter=
+//  - Interface1.implementMultipleSetter=
+//  - Interface2.implementMultipleSetter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass implements Interface1, Interface2 {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_setter.dart:24:12: Context: 'ConcreteClass.declareAbstractImplementMultipleSetter=' is defined here.
+//   void set declareAbstractImplementMultipleSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_setter.dart:6:12: Context: 'Interface1.implementMultipleSetter=' is defined here.
+//   void set implementMultipleSetter(int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_setter.dart:14:12: Context: 'Interface2.implementMultipleSetter=' is defined here.
+//   void set implementMultipleSetter(int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_setter.dart:33:7: Error: The non-abstract class 'ConcreteSub' is missing implementations for these members:
+//  - AbstractClass.declareAbstractImplementMultipleSetter=
+//  - Interface1.declareAbstractImplementMultipleSetter=
+//  - Interface1.implementMultipleSetter=
+//  - Interface2.declareAbstractImplementMultipleSetter=
+//  - Interface2.implementMultipleSetter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSub extends AbstractClass {}
+//       ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_setter.dart:30:12: Context: 'AbstractClass.declareAbstractImplementMultipleSetter=' is defined here.
+//   void set declareAbstractImplementMultipleSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_setter.dart:10:12: Context: 'Interface1.declareAbstractImplementMultipleSetter=' is defined here.
+//   void set declareAbstractImplementMultipleSetter(int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_setter.dart:6:12: Context: 'Interface1.implementMultipleSetter=' is defined here.
+//   void set implementMultipleSetter(int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_setter.dart:18:12: Context: 'Interface2.declareAbstractImplementMultipleSetter=' is defined here.
+//   void set declareAbstractImplementMultipleSetter(int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/implement_multiple_setter.dart:14:12: Context: 'Interface2.implementMultipleSetter=' is defined here.
+//   void set implementMultipleSetter(int i) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Interface1 extends core::Object {
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+  set implementMultipleSetter(core::int i) → void {}
+  set declareConcreteImplementMultipleSetter(core::int i) → void {}
+  set declareAbstractImplementMultipleSetter(core::int i) → void {}
+}
+class Interface2 extends core::Object {
+  synthetic constructor •() → self::Interface2
+    : super core::Object::•()
+    ;
+  set implementMultipleSetter(core::int i) → void {}
+  set declareConcreteImplementMultipleSetter(core::int i) → void {}
+  set declareAbstractImplementMultipleSetter(core::int i) → void {}
+}
+class ConcreteClass extends core::Object implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::ConcreteClass
+    : super core::Object::•()
+    ;
+  set declareConcreteImplementMultipleSetter(core::int i) → void {}
+  abstract set declareAbstractImplementMultipleSetter(core::int i) → void;
+}
+abstract class AbstractClass extends core::Object implements self::Interface1, self::Interface2 {
+  synthetic constructor •() → self::AbstractClass
+    : super core::Object::•()
+    ;
+  set declareConcreteImplementMultipleSetter(core::int i) → void {}
+  abstract set declareAbstractImplementMultipleSetter(core::int i) → void;
+}
+class ConcreteSub extends self::AbstractClass {
+  synthetic constructor •() → self::ConcreteSub
+    : super self::AbstractClass::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart.weak.modular.expect
new file mode 100644
index 0000000..efdaf3b
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart.weak.modular.expect
@@ -0,0 +1,230 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:9:7: Error: The implementation of 'optionalArgumentsMethod' in the non-abstract class 'Class' does not conform to its interface.
+// class Class /* error */ extends LegacyClass implements SuperQ {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in_lib1.dart:9:7: Context: The method 'Super.optionalArgumentsMethod' has fewer positional arguments than those of overridden method 'SuperExtra.optionalArgumentsMethod'.
+//   int optionalArgumentsMethod(int i) => i;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in_lib1.dart:13:7: Context: This is the overridden method ('optionalArgumentsMethod').
+//   int optionalArgumentsMethod(int i, [int? j]) => i;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:34:7: Error: The implementation of 'optionalArgumentsMethod' in the non-abstract class 'ClassQ' does not conform to its interface.
+// class ClassQ /* error */ extends LegacyClassQ implements Super {
+//       ^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in_lib1.dart:20:8: Context: The method 'SuperQ.optionalArgumentsMethod' has fewer positional arguments than those of overridden method 'SuperExtra.optionalArgumentsMethod'.
+//   int? optionalArgumentsMethod(int? i) => i;
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in_lib1.dart:13:7: Context: This is the overridden method ('optionalArgumentsMethod').
+//   int optionalArgumentsMethod(int i, [int? j]) => i;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:59:7: Error: The implementation of 'optionalArgumentsMethod' in the non-abstract class 'ClassMixedIn' does not conform to its interface.
+// class ClassMixedIn /* error */ extends LegacyMixedIn implements SuperQ {
+//       ^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in_lib1.dart:9:7: Context: The method 'Object with Super.optionalArgumentsMethod' has fewer positional arguments than those of overridden method 'SuperExtra.optionalArgumentsMethod'.
+//   int optionalArgumentsMethod(int i) => i;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in_lib1.dart:13:7: Context: This is the overridden method ('optionalArgumentsMethod').
+//   int optionalArgumentsMethod(int i, [int? j]) => i;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:59:7: Error: Class 'ClassMixedIn' inherits multiple members named 'nullabilityMethod' with incompatible signatures.
+// Try adding a declaration of 'nullabilityMethod' to 'ClassMixedIn'.
+// class ClassMixedIn /* error */ extends LegacyMixedIn implements SuperQ {
+//       ^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in_lib1.dart:6:7: Context: This is one of the overridden members.
+//   int nullabilityMethod(int i, {required int j}) => i;
+//       ^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in_lib1.dart:17:8: Context: This is one of the overridden members.
+//   int? nullabilityMethod(int? i, {int? j}) => i;
+//        ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:84:7: Error: The implementation of 'optionalArgumentsMethod' in the non-abstract class 'ClassMixedInQ' does not conform to its interface.
+// class ClassMixedInQ /* error */ extends LegacyMixedInQ implements Super {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in_lib1.dart:20:8: Context: The method 'Object with SuperQ.optionalArgumentsMethod' has fewer positional arguments than those of overridden method 'SuperExtra.optionalArgumentsMethod'.
+//   int? optionalArgumentsMethod(int? i) => i;
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in_lib1.dart:13:7: Context: This is the overridden method ('optionalArgumentsMethod').
+//   int optionalArgumentsMethod(int i, [int? j]) => i;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:84:7: Error: Class 'ClassMixedInQ' inherits multiple members named 'nullabilityMethod' with incompatible signatures.
+// Try adding a declaration of 'nullabilityMethod' to 'ClassMixedInQ'.
+// class ClassMixedInQ /* error */ extends LegacyMixedInQ implements Super {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in_lib1.dart:17:8: Context: This is one of the overridden members.
+//   int? nullabilityMethod(int? i, {int? j}) => i;
+//        ^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in_lib1.dart:6:7: Context: This is one of the overridden members.
+//   int nullabilityMethod(int i, {required int j}) => i;
+//       ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:21:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     super.optionalArgumentsMethod(null, null); // error
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:46:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     super.optionalArgumentsMethod(null, null); // error
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:52:25: Error: The value 'null' can't be assigned to a variable of type 'int' because 'int' is not nullable.
+//     nullabilitySetter = null; // error
+//                         ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:63:31: Error: Required named parameter 'j' must be provided.
+//     var v1 = nullabilityMethod(null); // ok
+//                               ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:71:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     super.optionalArgumentsMethod(null, null); // error
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:96:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     super.optionalArgumentsMethod(null, null); // error
+//                                  ^
+//
+import self as self;
+import "in_out_in_lib2.dart" as in_;
+import "in_out_in_lib1.dart" as in_2;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///in_out_in_lib1.dart";
+import "org-dartlang-testcase:///in_out_in_lib2.dart";
+
+class Class extends in_::LegacyClass implements in_2::SuperQ {
+  synthetic constructor •() → self::Class
+    : super in_::LegacyClass::•()
+    ;
+  method test() → dynamic {
+    core::int i;
+    core::int? v1 = this.{self::Class::nullabilityMethod}(null){(core::int?, {j: core::int?}) → core::int?};
+    i = super.{in_2::Super::nullabilityMethod}(null);
+    i = this.{in_::LegacyClass::optionalArgumentsMethod}(null, null){(core::int*, [core::int*]) →* core::int*};
+    i = super.{in_2::Super::optionalArgumentsMethod}(null);
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:21:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    super.optionalArgumentsMethod(null, null); // error
+                                 ^" in super.{in_2::Super::optionalArgumentsMethod}(null, null);
+    core::int? v2 = this.{self::Class::nullabilityGetter}{core::int?};
+    i = super.{in_2::Super::nullabilityGetter};
+    this.{self::Class::nullabilitySetter} = null;
+    super.{in_2::Super::nullabilitySetter} = null;
+  }
+  abstract member-signature method nullabilityMethod(core::int? i, {core::int? j}) → core::int?; -> in_2::Super::nullabilityMethod
+  abstract member-signature get nullabilityGetter() → core::int?; -> in_2::Super::nullabilityGetter
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+  abstract member-signature set nullabilitySetter(core::int? value) → void; -> in_2::Super::nullabilitySetter
+}
+class ClassQ extends in_::LegacyClassQ implements in_2::Super {
+  synthetic constructor •() → self::ClassQ
+    : super in_::LegacyClassQ::•()
+    ;
+  method test() → dynamic {
+    core::int i;
+    this.{in_::LegacyClassQ::nullabilityMethod}(null){(core::int*, {j: core::int*}) →* core::int*};
+    i = super.{in_2::SuperQ::nullabilityMethod}(null);
+    i = this.{in_::LegacyClassQ::optionalArgumentsMethod}(null, null){(core::int*, [core::int*]) →* core::int*};
+    i = super.{in_2::SuperQ::optionalArgumentsMethod}(null);
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:46:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    super.optionalArgumentsMethod(null, null); // error
+                                 ^" in super.{in_2::SuperQ::optionalArgumentsMethod}(null, null);
+    i = this.{self::ClassQ::nullabilityGetter}{core::int};
+    i = super.{in_2::SuperQ::nullabilityGetter};
+    this.{self::ClassQ::nullabilitySetter} = invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:52:25: Error: The value 'null' can't be assigned to a variable of type 'int' because 'int' is not nullable.
+    nullabilitySetter = null; // error
+                        ^" in null as{TypeError,ForNonNullableByDefault} core::int;
+    super.{in_2::SuperQ::nullabilitySetter} = null;
+  }
+  abstract member-signature get nullabilityGetter() → core::int; -> in_2::SuperQ::nullabilityGetter
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+  abstract member-signature set nullabilitySetter(core::int value) → void; -> in_2::SuperQ::nullabilitySetter
+}
+class ClassMixedIn extends in_::LegacyMixedIn implements in_2::SuperQ {
+  synthetic constructor •() → self::ClassMixedIn
+    : super in_::LegacyMixedIn::•()
+    ;
+  method test() → dynamic {
+    core::int i;
+    invalid-type v1 = invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:63:31: Error: Required named parameter 'j' must be provided.
+    var v1 = nullabilityMethod(null); // ok
+                              ^" in this.{in_::_LegacyMixedIn&Object&Super::nullabilityMethod}{<inapplicable>}.(null){(invalid-type) → invalid-type};
+    i = super.{in_::_LegacyMixedIn&Object&Super::nullabilityMethod}(null);
+    i = this.{in_::LegacyMixedIn::optionalArgumentsMethod}(null, null){(core::int*, [core::int*]) →* core::int*};
+    i = super.{in_::_LegacyMixedIn&Object&Super::optionalArgumentsMethod}(null);
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:71:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    super.optionalArgumentsMethod(null, null); // error
+                                 ^" in super.{in_::_LegacyMixedIn&Object&Super::optionalArgumentsMethod}(null, null);
+    core::int v2 = this.{in_::_LegacyMixedIn&Object&Super::nullabilityGetter}{core::int};
+    i = super.{in_::_LegacyMixedIn&Object&Super::nullabilityGetter};
+    this.{self::ClassMixedIn::nullabilitySetter} = null;
+    super.{in_::_LegacyMixedIn&Object&Super::nullabilitySetter} = null;
+  }
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+  abstract member-signature set nullabilitySetter(core::int? value) → void; -> in_2::SuperQ::nullabilitySetter
+}
+class ClassMixedInQ extends in_::LegacyMixedInQ implements in_2::Super {
+  synthetic constructor •() → self::ClassMixedInQ
+    : super in_::LegacyMixedInQ::•()
+    ;
+  method test() → dynamic {
+    core::int i;
+    this.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilityMethod}(null){(core::int?, {j: core::int?}) →* core::int?};
+    i = super.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilityMethod}(null);
+    i = this.{in_::LegacyMixedInQ::optionalArgumentsMethod}(null, null){(core::int*, [core::int*]) →* core::int*};
+    i = super.{in_::_LegacyMixedInQ&Object&SuperQ::optionalArgumentsMethod}(null);
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_dill_out_in/in_out_in.dart:96:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    super.optionalArgumentsMethod(null, null); // error
+                                 ^" in super.{in_::_LegacyMixedInQ&Object&SuperQ::optionalArgumentsMethod}(null, null);
+    i = this.{self::ClassMixedInQ::nullabilityGetter}{core::int};
+    i = super.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilityGetter};
+    this.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilitySetter} = null;
+    super.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilitySetter} = null;
+  }
+  abstract member-signature get nullabilityGetter() → core::int; -> in_2::Super::nullabilityGetter
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart.weak.modular.expect
new file mode 100644
index 0000000..1f01c40
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart.weak.modular.expect
@@ -0,0 +1,315 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:9:7: Error: The implementation of 'optionalArgumentsMethod' in the non-abstract class 'Class' does not conform to its interface.
+// class Class /* error */ extends LegacyClass implements SuperQ {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in_lib1.dart:9:7: Context: The method 'Super.optionalArgumentsMethod' has fewer positional arguments than those of overridden method 'SuperExtra.optionalArgumentsMethod'.
+//   int optionalArgumentsMethod(int i) => i;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in_lib1.dart:13:7: Context: This is the overridden method ('optionalArgumentsMethod').
+//   int optionalArgumentsMethod(int i, [int? j]) => i;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:34:7: Error: The implementation of 'optionalArgumentsMethod' in the non-abstract class 'ClassQ' does not conform to its interface.
+// class ClassQ /* error */ extends LegacyClassQ implements Super {
+//       ^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in_lib1.dart:20:8: Context: The method 'SuperQ.optionalArgumentsMethod' has fewer positional arguments than those of overridden method 'SuperExtra.optionalArgumentsMethod'.
+//   int? optionalArgumentsMethod(int? i) => i;
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in_lib1.dart:13:7: Context: This is the overridden method ('optionalArgumentsMethod').
+//   int optionalArgumentsMethod(int i, [int? j]) => i;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:59:7: Error: The implementation of 'optionalArgumentsMethod' in the non-abstract class 'ClassMixedIn' does not conform to its interface.
+// class ClassMixedIn /* error */ extends LegacyMixedIn implements SuperQ {
+//       ^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in_lib2.dart:13:16: Context: The method 'Object with Super.optionalArgumentsMethod' has fewer positional arguments than those of overridden method 'SuperExtra.optionalArgumentsMethod'.
+// abstract class LegacyMixedIn with Super implements SuperExtra {}
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in_lib1.dart:13:7: Context: This is the overridden method ('optionalArgumentsMethod').
+//   int optionalArgumentsMethod(int i, [int? j]) => i;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:84:7: Error: The implementation of 'optionalArgumentsMethod' in the non-abstract class 'ClassMixedInQ' does not conform to its interface.
+// class ClassMixedInQ /* error */ extends LegacyMixedInQ implements Super {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in_lib2.dart:15:16: Context: The method 'Object with SuperQ.optionalArgumentsMethod' has fewer positional arguments than those of overridden method 'SuperExtra.optionalArgumentsMethod'.
+// abstract class LegacyMixedInQ with SuperQ implements SuperExtra {}
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in_lib1.dart:13:7: Context: This is the overridden method ('optionalArgumentsMethod').
+//   int optionalArgumentsMethod(int i, [int? j]) => i;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:21:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     super.optionalArgumentsMethod(null, null); // error
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:46:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     super.optionalArgumentsMethod(null, null); // error
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:52:25: Error: The value 'null' can't be assigned to a variable of type 'int' because 'int' is not nullable.
+//     nullabilitySetter = null; // error
+//                         ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:71:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     super.optionalArgumentsMethod(null, null); // error
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:96:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     super.optionalArgumentsMethod(null, null); // error
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:102:25: Error: The value 'null' can't be assigned to a variable of type 'int' because 'int' is not nullable.
+//     nullabilitySetter = null; // error
+//                         ^
+//
+import self as self;
+import "in_out_in_lib2.dart" as in_;
+import "in_out_in_lib1.dart" as in_2;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///in_out_in_lib1.dart";
+import "org-dartlang-testcase:///in_out_in_lib2.dart";
+
+class Class extends in_::LegacyClass implements in_2::SuperQ {
+  synthetic constructor •() → self::Class
+    : super in_::LegacyClass::•()
+    ;
+  method test() → dynamic {
+    core::int i;
+    core::int? v1 = this.{self::Class::nullabilityMethod}(null){(core::int?, {j: core::int?}) → core::int?};
+    i = super.{in_2::Super::nullabilityMethod}(null);
+    i = this.{in_::LegacyClass::optionalArgumentsMethod}(null, null){(core::int*, [core::int*]) →* core::int*};
+    i = super.{in_2::Super::optionalArgumentsMethod}(null);
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:21:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    super.optionalArgumentsMethod(null, null); // error
+                                 ^" in super.{in_2::Super::optionalArgumentsMethod}(null, null);
+    core::int? v2 = this.{self::Class::nullabilityGetter}{core::int?};
+    i = super.{in_2::Super::nullabilityGetter};
+    this.{self::Class::nullabilitySetter} = null;
+    super.{in_2::Super::nullabilitySetter} = null;
+  }
+  abstract member-signature method nullabilityMethod(core::int? i, {core::int? j}) → core::int?; -> in_2::Super::nullabilityMethod
+  abstract member-signature get nullabilityGetter() → core::int?; -> in_2::Super::nullabilityGetter
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+  abstract member-signature set nullabilitySetter(core::int? value) → void; -> in_2::Super::nullabilitySetter
+}
+class ClassQ extends in_::LegacyClassQ implements in_2::Super {
+  synthetic constructor •() → self::ClassQ
+    : super in_::LegacyClassQ::•()
+    ;
+  method test() → dynamic {
+    core::int i;
+    this.{in_::LegacyClassQ::nullabilityMethod}(null){(core::int*, {j: core::int*}) →* core::int*};
+    i = super.{in_2::SuperQ::nullabilityMethod}(null);
+    i = this.{in_::LegacyClassQ::optionalArgumentsMethod}(null, null){(core::int*, [core::int*]) →* core::int*};
+    i = super.{in_2::SuperQ::optionalArgumentsMethod}(null);
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:46:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    super.optionalArgumentsMethod(null, null); // error
+                                 ^" in super.{in_2::SuperQ::optionalArgumentsMethod}(null, null);
+    i = this.{self::ClassQ::nullabilityGetter}{core::int};
+    i = super.{in_2::SuperQ::nullabilityGetter};
+    this.{self::ClassQ::nullabilitySetter} = invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:52:25: Error: The value 'null' can't be assigned to a variable of type 'int' because 'int' is not nullable.
+    nullabilitySetter = null; // error
+                        ^" in null as{TypeError,ForNonNullableByDefault} core::int;
+    super.{in_2::SuperQ::nullabilitySetter} = null;
+  }
+  abstract member-signature get nullabilityGetter() → core::int; -> in_2::SuperQ::nullabilityGetter
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+  abstract member-signature set nullabilitySetter(core::int value) → void; -> in_2::SuperQ::nullabilitySetter
+}
+class ClassMixedIn extends in_::LegacyMixedIn implements in_2::SuperQ {
+  synthetic constructor •() → self::ClassMixedIn
+    : super in_::LegacyMixedIn::•()
+    ;
+  method test() → dynamic {
+    core::int i;
+    core::int? v1 = this.{self::ClassMixedIn::nullabilityMethod}(null){(core::int?, {j: core::int?}) → core::int?};
+    i = super.{in_::_LegacyMixedIn&Object&Super::nullabilityMethod}(null);
+    i = this.{in_::LegacyMixedIn::optionalArgumentsMethod}(null, null){(core::int*, [core::int*]) →* core::int*};
+    i = super.{in_::_LegacyMixedIn&Object&Super::optionalArgumentsMethod}(null);
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:71:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    super.optionalArgumentsMethod(null, null); // error
+                                 ^" in super.{in_::_LegacyMixedIn&Object&Super::optionalArgumentsMethod}(null, null);
+    core::int? v2 = this.{self::ClassMixedIn::nullabilityGetter}{core::int?};
+    i = super.{in_::_LegacyMixedIn&Object&Super::nullabilityGetter};
+    this.{self::ClassMixedIn::nullabilitySetter} = null;
+    super.{in_::_LegacyMixedIn&Object&Super::nullabilitySetter} = null;
+  }
+  abstract member-signature method nullabilityMethod(core::int? i, {core::int? j}) → core::int?; -> in_::_LegacyMixedIn&Object&Super::nullabilityMethod
+  abstract member-signature get nullabilityGetter() → core::int?; -> in_::_LegacyMixedIn&Object&Super::nullabilityGetter
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+  abstract member-signature set nullabilitySetter(core::int? value) → void; -> in_::_LegacyMixedIn&Object&Super::nullabilitySetter
+}
+class ClassMixedInQ extends in_::LegacyMixedInQ implements in_2::Super {
+  synthetic constructor •() → self::ClassMixedInQ
+    : super in_::LegacyMixedInQ::•()
+    ;
+  method test() → dynamic {
+    core::int i;
+    this.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilityMethod}(null){(core::int*, {j: core::int*}) →* core::int*};
+    i = super.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilityMethod}(null);
+    i = this.{in_::LegacyMixedInQ::optionalArgumentsMethod}(null, null){(core::int*, [core::int*]) →* core::int*};
+    i = super.{in_::_LegacyMixedInQ&Object&SuperQ::optionalArgumentsMethod}(null);
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:96:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    super.optionalArgumentsMethod(null, null); // error
+                                 ^" in super.{in_::_LegacyMixedInQ&Object&SuperQ::optionalArgumentsMethod}(null, null);
+    i = this.{self::ClassMixedInQ::nullabilityGetter}{core::int};
+    i = super.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilityGetter};
+    this.{self::ClassMixedInQ::nullabilitySetter} = invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_dill_in/in_out_in.dart:102:25: Error: The value 'null' can't be assigned to a variable of type 'int' because 'int' is not nullable.
+    nullabilitySetter = null; // error
+                        ^" in null as{TypeError,ForNonNullableByDefault} core::int;
+    super.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilitySetter} = null;
+  }
+  abstract member-signature get nullabilityGetter() → core::int; -> in_::_LegacyMixedInQ&Object&SuperQ::nullabilityGetter
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+  abstract member-signature set nullabilitySetter(core::int value) → void; -> in_::_LegacyMixedInQ&Object&SuperQ::nullabilitySetter
+}
+static method main() → dynamic {}
+
+library;
+import self as in_;
+import "in_out_in_lib1.dart" as in_2;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///in_out_in_lib1.dart";
+
+abstract class LegacyClass extends in_2::Super implements in_2::SuperExtra {
+  synthetic constructor •() → in_::LegacyClass*
+    : super in_2::Super::•()
+    ;
+  abstract member-signature method nullabilityMethod(core::int* i, {core::int* j}) → core::int*; -> in_2::Super::nullabilityMethod
+  abstract member-signature get nullabilityGetter() → core::int*; -> in_2::Super::nullabilityGetter
+  abstract member-signature method optionalArgumentsMethod(core::int* i, [core::int* j]) → core::int*; -> in_2::SuperExtra::optionalArgumentsMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature set nullabilitySetter(core::int* value) → void; -> in_2::Super::nullabilitySetter
+}
+abstract class LegacyClassQ extends in_2::SuperQ implements in_2::SuperExtra {
+  synthetic constructor •() → in_::LegacyClassQ*
+    : super in_2::SuperQ::•()
+    ;
+  abstract member-signature method nullabilityMethod(core::int* i, {core::int* j}) → core::int*; -> in_2::SuperQ::nullabilityMethod
+  abstract member-signature get nullabilityGetter() → core::int*; -> in_2::SuperQ::nullabilityGetter
+  abstract member-signature method optionalArgumentsMethod(core::int* i, [core::int* j]) → core::int*; -> in_2::SuperExtra::optionalArgumentsMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature set nullabilitySetter(core::int* value) → void; -> in_2::SuperQ::nullabilitySetter
+}
+abstract class _LegacyMixedIn&Object&Super = core::Object with in_2::Super /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → in_::_LegacyMixedIn&Object&Super*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method nullabilityMethod(core::int* i, {core::int* j}) → core::int*
+    return super.{in_2::Super::nullabilityMethod}(i, j: j);
+  mixin-super-stub get nullabilityGetter() → core::int*
+    return super.{in_2::Super::nullabilityGetter};
+  mixin-super-stub method optionalArgumentsMethod(core::int* i) → core::int*
+    return super.{in_2::Super::optionalArgumentsMethod}(i);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  mixin-super-stub set nullabilitySetter(core::int* value) → void
+    return super.{in_2::Super::nullabilitySetter} = value;
+}
+abstract class LegacyMixedIn extends in_::_LegacyMixedIn&Object&Super implements in_2::SuperExtra {
+  synthetic constructor •() → in_::LegacyMixedIn*
+    : super in_::_LegacyMixedIn&Object&Super::•()
+    ;
+  abstract member-signature method optionalArgumentsMethod(core::int* i, [core::int* j]) → core::int*; -> in_2::SuperExtra::optionalArgumentsMethod
+}
+abstract class _LegacyMixedInQ&Object&SuperQ = core::Object with in_2::SuperQ /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → in_::_LegacyMixedInQ&Object&SuperQ*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method nullabilityMethod(core::int* i, {core::int* j}) → core::int*
+    return super.{in_2::SuperQ::nullabilityMethod}(i, j: j);
+  mixin-super-stub get nullabilityGetter() → core::int*
+    return super.{in_2::SuperQ::nullabilityGetter};
+  mixin-super-stub method optionalArgumentsMethod(core::int* i) → core::int*
+    return super.{in_2::SuperQ::optionalArgumentsMethod}(i);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  mixin-super-stub set nullabilitySetter(core::int* value) → void
+    return super.{in_2::SuperQ::nullabilitySetter} = value;
+}
+abstract class LegacyMixedInQ extends in_::_LegacyMixedInQ&Object&SuperQ implements in_2::SuperExtra {
+  synthetic constructor •() → in_::LegacyMixedInQ*
+    : super in_::_LegacyMixedInQ&Object&SuperQ::•()
+    ;
+  abstract member-signature method optionalArgumentsMethod(core::int* i, [core::int* j]) → core::int*; -> in_2::SuperExtra::optionalArgumentsMethod
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart.weak.modular.expect
new file mode 100644
index 0000000..a4ccce2
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart.weak.modular.expect
@@ -0,0 +1,369 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:9:7: Error: The implementation of 'optionalArgumentsMethod' in the non-abstract class 'Class' does not conform to its interface.
+// class Class /* error */ extends LegacyClass implements SuperQ {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in_lib1.dart:9:7: Context: The method 'Super.optionalArgumentsMethod' has fewer positional arguments than those of overridden method 'SuperExtra.optionalArgumentsMethod'.
+//   int optionalArgumentsMethod(int i) => i;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in_lib1.dart:13:7: Context: This is the overridden method ('optionalArgumentsMethod').
+//   int optionalArgumentsMethod(int i, [int? j]) => i;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:34:7: Error: The implementation of 'optionalArgumentsMethod' in the non-abstract class 'ClassQ' does not conform to its interface.
+// class ClassQ /* error */ extends LegacyClassQ implements Super {
+//       ^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in_lib1.dart:20:8: Context: The method 'SuperQ.optionalArgumentsMethod' has fewer positional arguments than those of overridden method 'SuperExtra.optionalArgumentsMethod'.
+//   int? optionalArgumentsMethod(int? i) => i;
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in_lib1.dart:13:7: Context: This is the overridden method ('optionalArgumentsMethod').
+//   int optionalArgumentsMethod(int i, [int? j]) => i;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:59:7: Error: The implementation of 'optionalArgumentsMethod' in the non-abstract class 'ClassMixedIn' does not conform to its interface.
+// class ClassMixedIn /* error */ extends LegacyMixedIn implements SuperQ {
+//       ^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in_lib2.dart:13:16: Context: The method 'Object with Super.optionalArgumentsMethod' has fewer positional arguments than those of overridden method 'SuperExtra.optionalArgumentsMethod'.
+// abstract class LegacyMixedIn with Super implements SuperExtra {}
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in_lib1.dart:13:7: Context: This is the overridden method ('optionalArgumentsMethod').
+//   int optionalArgumentsMethod(int i, [int? j]) => i;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:84:7: Error: The implementation of 'optionalArgumentsMethod' in the non-abstract class 'ClassMixedInQ' does not conform to its interface.
+// class ClassMixedInQ /* error */ extends LegacyMixedInQ implements Super {
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in_lib2.dart:15:16: Context: The method 'Object with SuperQ.optionalArgumentsMethod' has fewer positional arguments than those of overridden method 'SuperExtra.optionalArgumentsMethod'.
+// abstract class LegacyMixedInQ with SuperQ implements SuperExtra {}
+//                ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in_lib1.dart:13:7: Context: This is the overridden method ('optionalArgumentsMethod').
+//   int optionalArgumentsMethod(int i, [int? j]) => i;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:21:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     super.optionalArgumentsMethod(null, null); // error
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:38:23: Error: The value 'null' can't be assigned to the parameter type 'int' because 'int' is not nullable.
+//     nullabilityMethod(null); // error
+//                       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:46:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     super.optionalArgumentsMethod(null, null); // error
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:52:25: Error: The value 'null' can't be assigned to a variable of type 'int' because 'int' is not nullable.
+//     nullabilitySetter = null; // error
+//                         ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:71:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     super.optionalArgumentsMethod(null, null); // error
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:88:23: Error: The value 'null' can't be assigned to the parameter type 'int' because 'int' is not nullable.
+//     nullabilityMethod(null); // error
+//                       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:96:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     super.optionalArgumentsMethod(null, null); // error
+//                                  ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:102:25: Error: The value 'null' can't be assigned to a variable of type 'int' because 'int' is not nullable.
+//     nullabilitySetter = null; // error
+//                         ^
+//
+import self as self;
+import "in_out_in_lib2.dart" as in_;
+import "in_out_in_lib1.dart" as in_2;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///in_out_in_lib1.dart";
+import "org-dartlang-testcase:///in_out_in_lib2.dart";
+
+class Class extends in_::LegacyClass implements in_2::SuperQ {
+  synthetic constructor •() → self::Class
+    : super in_::LegacyClass::•()
+    ;
+  method test() → dynamic {
+    core::int i;
+    core::int? v1 = this.{self::Class::nullabilityMethod}(null){(core::int?) → core::int?};
+    i = super.{in_2::Super::nullabilityMethod}(null);
+    i = this.{in_::LegacyClass::optionalArgumentsMethod}(null, null){(core::int*, [core::int*]) →* core::int*};
+    i = super.{in_2::Super::optionalArgumentsMethod}(null);
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:21:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    super.optionalArgumentsMethod(null, null); // error
+                                 ^" in super.{in_2::Super::optionalArgumentsMethod}(null, null);
+    core::int? v2 = this.{self::Class::nullabilityGetter}{core::int?};
+    i = super.{in_2::Super::nullabilityGetter};
+    this.{self::Class::nullabilitySetter} = null;
+    super.{in_2::Super::nullabilitySetter} = null;
+  }
+  abstract member-signature method nullabilityMethod(core::int? i) → core::int?; -> in_2::Super::nullabilityMethod
+  abstract member-signature get nullabilityGetter() → core::int?; -> in_2::Super::nullabilityGetter
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+  abstract member-signature set nullabilitySetter(core::int? value) → void; -> in_2::Super::nullabilitySetter
+}
+class ClassQ extends in_::LegacyClassQ implements in_2::Super {
+  synthetic constructor •() → self::ClassQ
+    : super in_::LegacyClassQ::•()
+    ;
+  method test() → dynamic {
+    core::int i;
+    this.{self::ClassQ::nullabilityMethod}(invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:38:23: Error: The value 'null' can't be assigned to the parameter type 'int' because 'int' is not nullable.
+    nullabilityMethod(null); // error
+                      ^" in null as{TypeError,ForNonNullableByDefault} core::int){(core::int) → core::int};
+    i = super.{in_2::SuperQ::nullabilityMethod}(null);
+    i = this.{in_::LegacyClassQ::optionalArgumentsMethod}(null, null){(core::int*, [core::int*]) →* core::int*};
+    i = super.{in_2::SuperQ::optionalArgumentsMethod}(null);
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:46:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    super.optionalArgumentsMethod(null, null); // error
+                                 ^" in super.{in_2::SuperQ::optionalArgumentsMethod}(null, null);
+    i = this.{self::ClassQ::nullabilityGetter}{core::int};
+    i = super.{in_2::SuperQ::nullabilityGetter};
+    this.{self::ClassQ::nullabilitySetter} = invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:52:25: Error: The value 'null' can't be assigned to a variable of type 'int' because 'int' is not nullable.
+    nullabilitySetter = null; // error
+                        ^" in null as{TypeError,ForNonNullableByDefault} core::int;
+    super.{in_2::SuperQ::nullabilitySetter} = null;
+  }
+  abstract member-signature method nullabilityMethod(core::int i) → core::int; -> in_2::SuperQ::nullabilityMethod
+  abstract member-signature get nullabilityGetter() → core::int; -> in_2::SuperQ::nullabilityGetter
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+  abstract member-signature set nullabilitySetter(core::int value) → void; -> in_2::SuperQ::nullabilitySetter
+}
+class ClassMixedIn extends in_::LegacyMixedIn implements in_2::SuperQ {
+  synthetic constructor •() → self::ClassMixedIn
+    : super in_::LegacyMixedIn::•()
+    ;
+  method test() → dynamic {
+    core::int i;
+    core::int? v1 = this.{self::ClassMixedIn::nullabilityMethod}(null){(core::int?) → core::int?};
+    i = super.{in_::_LegacyMixedIn&Object&Super::nullabilityMethod}(null);
+    i = this.{in_::LegacyMixedIn::optionalArgumentsMethod}(null, null){(core::int*, [core::int*]) →* core::int*};
+    i = super.{in_::_LegacyMixedIn&Object&Super::optionalArgumentsMethod}(null);
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:71:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    super.optionalArgumentsMethod(null, null); // error
+                                 ^" in super.{in_::_LegacyMixedIn&Object&Super::optionalArgumentsMethod}(null, null);
+    core::int? v2 = this.{self::ClassMixedIn::nullabilityGetter}{core::int?};
+    i = super.{in_::_LegacyMixedIn&Object&Super::nullabilityGetter};
+    this.{self::ClassMixedIn::nullabilitySetter} = null;
+    super.{in_::_LegacyMixedIn&Object&Super::nullabilitySetter} = null;
+  }
+  abstract member-signature method nullabilityMethod(core::int? i) → core::int?; -> in_::_LegacyMixedIn&Object&Super::nullabilityMethod
+  abstract member-signature get nullabilityGetter() → core::int?; -> in_::_LegacyMixedIn&Object&Super::nullabilityGetter
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+  abstract member-signature set nullabilitySetter(core::int? value) → void; -> in_::_LegacyMixedIn&Object&Super::nullabilitySetter
+}
+class ClassMixedInQ extends in_::LegacyMixedInQ implements in_2::Super {
+  synthetic constructor •() → self::ClassMixedInQ
+    : super in_::LegacyMixedInQ::•()
+    ;
+  method test() → dynamic {
+    core::int i;
+    this.{self::ClassMixedInQ::nullabilityMethod}(invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:88:23: Error: The value 'null' can't be assigned to the parameter type 'int' because 'int' is not nullable.
+    nullabilityMethod(null); // error
+                      ^" in null as{TypeError,ForNonNullableByDefault} core::int){(core::int) → core::int};
+    i = super.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilityMethod}(null);
+    i = this.{in_::LegacyMixedInQ::optionalArgumentsMethod}(null, null){(core::int*, [core::int*]) →* core::int*};
+    i = super.{in_::_LegacyMixedInQ&Object&SuperQ::optionalArgumentsMethod}(null);
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:96:34: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+    super.optionalArgumentsMethod(null, null); // error
+                                 ^" in super.{in_::_LegacyMixedInQ&Object&SuperQ::optionalArgumentsMethod}(null, null);
+    i = this.{self::ClassMixedInQ::nullabilityGetter}{core::int};
+    i = super.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilityGetter};
+    this.{self::ClassMixedInQ::nullabilitySetter} = invalid-expression "pkg/front_end/testcases/nnbd_mixed/hierarchy/in_out_in.dart:102:25: Error: The value 'null' can't be assigned to a variable of type 'int' because 'int' is not nullable.
+    nullabilitySetter = null; // error
+                        ^" in null as{TypeError,ForNonNullableByDefault} core::int;
+    super.{in_::_LegacyMixedInQ&Object&SuperQ::nullabilitySetter} = null;
+  }
+  abstract member-signature method nullabilityMethod(core::int i) → core::int; -> in_::_LegacyMixedInQ&Object&SuperQ::nullabilityMethod
+  abstract member-signature get nullabilityGetter() → core::int; -> in_::_LegacyMixedInQ&Object&SuperQ::nullabilityGetter
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+  abstract member-signature set nullabilitySetter(core::int value) → void; -> in_::_LegacyMixedInQ&Object&SuperQ::nullabilitySetter
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as in_2;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → in_2::Super
+    : super core::Object::•()
+    ;
+  method nullabilityMethod(core::int i) → core::int
+    return i;
+  get nullabilityGetter() → core::int
+    return 0;
+  set nullabilitySetter(core::int value) → void {}
+  method optionalArgumentsMethod(core::int i) → core::int
+    return i;
+}
+abstract class SuperExtra extends core::Object {
+  synthetic constructor •() → in_2::SuperExtra
+    : super core::Object::•()
+    ;
+  method optionalArgumentsMethod(core::int i, [core::int? j = #C1]) → core::int
+    return i;
+}
+abstract class SuperQ extends core::Object {
+  synthetic constructor •() → in_2::SuperQ
+    : super core::Object::•()
+    ;
+  method nullabilityMethod(core::int? i) → core::int?
+    return i;
+  get nullabilityGetter() → core::int?
+    return null;
+  set nullabilitySetter(core::int? value) → void {}
+  method optionalArgumentsMethod(core::int? i) → core::int?
+    return i;
+}
+
+library;
+import self as in_;
+import "in_out_in_lib1.dart" as in_2;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///in_out_in_lib1.dart";
+
+abstract class LegacyClass extends in_2::Super implements in_2::SuperExtra {
+  synthetic constructor •() → in_::LegacyClass*
+    : super in_2::Super::•()
+    ;
+  abstract member-signature method nullabilityMethod(core::int* i) → core::int*; -> in_2::Super::nullabilityMethod
+  abstract member-signature get nullabilityGetter() → core::int*; -> in_2::Super::nullabilityGetter
+  abstract member-signature method optionalArgumentsMethod(core::int* i, [core::int* j = #C1]) → core::int*; -> in_2::SuperExtra::optionalArgumentsMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature set nullabilitySetter(core::int* value) → void; -> in_2::Super::nullabilitySetter
+}
+abstract class LegacyClassQ extends in_2::SuperQ implements in_2::SuperExtra {
+  synthetic constructor •() → in_::LegacyClassQ*
+    : super in_2::SuperQ::•()
+    ;
+  abstract member-signature method nullabilityMethod(core::int* i) → core::int*; -> in_2::SuperQ::nullabilityMethod
+  abstract member-signature get nullabilityGetter() → core::int*; -> in_2::SuperQ::nullabilityGetter
+  abstract member-signature method optionalArgumentsMethod(core::int* i, [core::int* j = #C1]) → core::int*; -> in_2::SuperExtra::optionalArgumentsMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature set nullabilitySetter(core::int* value) → void; -> in_2::SuperQ::nullabilitySetter
+}
+abstract class _LegacyMixedIn&Object&Super = core::Object with in_2::Super /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → in_::_LegacyMixedIn&Object&Super*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method nullabilityMethod(core::int* i) → core::int*
+    return super.{in_2::Super::nullabilityMethod}(i);
+  mixin-super-stub get nullabilityGetter() → core::int*
+    return super.{in_2::Super::nullabilityGetter};
+  mixin-super-stub method optionalArgumentsMethod(core::int* i) → core::int*
+    return super.{in_2::Super::optionalArgumentsMethod}(i);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  mixin-super-stub set nullabilitySetter(core::int* value) → void
+    return super.{in_2::Super::nullabilitySetter} = value;
+}
+abstract class LegacyMixedIn extends in_::_LegacyMixedIn&Object&Super implements in_2::SuperExtra {
+  synthetic constructor •() → in_::LegacyMixedIn*
+    : super in_::_LegacyMixedIn&Object&Super::•()
+    ;
+  abstract member-signature method optionalArgumentsMethod(core::int* i, [core::int* j = #C1]) → core::int*; -> in_2::SuperExtra::optionalArgumentsMethod
+}
+abstract class _LegacyMixedInQ&Object&SuperQ = core::Object with in_2::SuperQ /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → in_::_LegacyMixedInQ&Object&SuperQ*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method nullabilityMethod(core::int* i) → core::int*
+    return super.{in_2::SuperQ::nullabilityMethod}(i);
+  mixin-super-stub get nullabilityGetter() → core::int*
+    return super.{in_2::SuperQ::nullabilityGetter};
+  mixin-super-stub method optionalArgumentsMethod(core::int* i) → core::int*
+    return super.{in_2::SuperQ::optionalArgumentsMethod}(i);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  mixin-super-stub set nullabilitySetter(core::int* value) → void
+    return super.{in_2::SuperQ::nullabilitySetter} = value;
+}
+abstract class LegacyMixedInQ extends in_::_LegacyMixedInQ&Object&SuperQ implements in_2::SuperExtra {
+  synthetic constructor •() → in_::LegacyMixedInQ*
+    : super in_::_LegacyMixedInQ&Object&SuperQ::•()
+    ;
+  abstract member-signature method optionalArgumentsMethod(core::int* i, [core::int* j = #C1]) → core::int*; -> in_2::SuperExtra::optionalArgumentsMethod
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart.weak.modular.expect
new file mode 100644
index 0000000..eeb8541
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart.weak.modular.expect
@@ -0,0 +1,265 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:34:7: Error: The non-abstract class 'ClassImplements' is missing implementations for these members:
+//  - Interface2.extendedMethod
+//  - Interface2.mixedInMethod
+//  - Mixin.mixedInMethod
+//  - Super with Mixin.mixedInMethod
+//  - Super.extendedMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ClassImplements implements Interface2 {}
+//       ^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:19:7: Context: 'Interface2.extendedMethod' is defined here.
+//   int extendedMethod();
+//       ^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:20:7: Context: 'Interface2.mixedInMethod' is defined here.
+//   int mixedInMethod();
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:10:7: Context: 'Mixin.mixedInMethod' is defined here.
+//   num mixedInMethod() => 0;
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:10:7: Context: 'Super with Mixin.mixedInMethod' is defined here.
+//   num mixedInMethod() => 0;
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:6:7: Context: 'Super.extendedMethod' is defined here.
+//   num extendedMethod() => 0;
+//       ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:23:7: Error: The implementation of 'mixedInMethod' in the non-abstract class 'ClassExtends' does not conform to its interface.
+// class ClassExtends extends Super with Mixin implements Interface1 {}
+//       ^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:23:7: Context: The return type of the method 'Super with Mixin.mixedInMethod' is 'num', which does not match the return type, 'int', of the overridden method, 'Interface1.mixedInMethod'.
+// Change to a subtype of 'int'.
+// class ClassExtends extends Super with Mixin implements Interface1 {}
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:15:7: Context: This is the overridden method ('mixedInMethod').
+//   int mixedInMethod();
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:23:7: Error: The implementation of 'extendedMethod' in the non-abstract class 'ClassExtends' does not conform to its interface.
+// class ClassExtends extends Super with Mixin implements Interface1 {}
+//       ^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:6:7: Context: The return type of the method 'Super.extendedMethod' is 'num', which does not match the return type, 'int', of the overridden method, 'Interface1.extendedMethod'.
+// Change to a subtype of 'int'.
+//   num extendedMethod() => 0;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:14:7: Context: This is the overridden method ('extendedMethod').
+//   int extendedMethod();
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:25:7: Error: The implementation of 'mixedInMethod' in the non-abstract class 'ClassExtendsWithNoSuchMethod' does not conform to its interface.
+// class ClassExtendsWithNoSuchMethod extends Super
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:25:7: Context: The return type of the method 'Super with Mixin.mixedInMethod' is 'num', which does not match the return type, 'int', of the overridden method, 'Interface1.mixedInMethod'.
+// Change to a subtype of 'int'.
+// class ClassExtendsWithNoSuchMethod extends Super
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:15:7: Context: This is the overridden method ('mixedInMethod').
+//   int mixedInMethod();
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:25:7: Error: The implementation of 'extendedMethod' in the non-abstract class 'ClassExtendsWithNoSuchMethod' does not conform to its interface.
+// class ClassExtendsWithNoSuchMethod extends Super
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:6:7: Context: The return type of the method 'Super.extendedMethod' is 'num', which does not match the return type, 'int', of the overridden method, 'Interface1.extendedMethod'.
+// Change to a subtype of 'int'.
+//   num extendedMethod() => 0;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:14:7: Context: This is the overridden method ('extendedMethod').
+//   int extendedMethod();
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:43:7: Error: The implementation of 'extendedMethod' in the non-abstract class 'ClassDeclaresExtends' does not conform to its interface.
+// class ClassDeclaresExtends extends Super with Mixin {
+//       ^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:6:7: Context: The return type of the method 'Super.extendedMethod' is 'num', which does not match the return type, 'int', of the overridden method, 'ClassDeclaresExtends.extendedMethod'.
+// Change to a subtype of 'int'.
+//   num extendedMethod() => 0;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:44:7: Context: This is the overridden method ('extendedMethod').
+//   int extendedMethod();
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:43:7: Error: The implementation of 'mixedInMethod' in the non-abstract class 'ClassDeclaresExtends' does not conform to its interface.
+// class ClassDeclaresExtends extends Super with Mixin {
+//       ^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:43:7: Context: The return type of the method 'Super with Mixin.mixedInMethod' is 'num', which does not match the return type, 'int', of the overridden method, 'ClassDeclaresExtends.mixedInMethod'.
+// Change to a subtype of 'int'.
+// class ClassDeclaresExtends extends Super with Mixin {
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:45:7: Context: This is the overridden method ('mixedInMethod').
+//   int mixedInMethod();
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:48:7: Error: The implementation of 'extendedMethod' in the non-abstract class 'ClassDeclaresExtendsWithNoSuchMethod' does not conform to its interface.
+// class ClassDeclaresExtendsWithNoSuchMethod extends Super with Mixin {
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:6:7: Context: The return type of the method 'Super.extendedMethod' is 'num', which does not match the return type, 'int', of the overridden method, 'ClassDeclaresExtendsWithNoSuchMethod.extendedMethod'.
+// Change to a subtype of 'int'.
+//   num extendedMethod() => 0;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:54:7: Context: This is the overridden method ('extendedMethod').
+//   int extendedMethod();
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:48:7: Error: The implementation of 'mixedInMethod' in the non-abstract class 'ClassDeclaresExtendsWithNoSuchMethod' does not conform to its interface.
+// class ClassDeclaresExtendsWithNoSuchMethod extends Super with Mixin {
+//       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:48:7: Context: The return type of the method 'Super with Mixin.mixedInMethod' is 'num', which does not match the return type, 'int', of the overridden method, 'ClassDeclaresExtendsWithNoSuchMethod.mixedInMethod'.
+// Change to a subtype of 'int'.
+// class ClassDeclaresExtendsWithNoSuchMethod extends Super with Mixin {
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/inherited_implements.dart:55:7: Context: This is the overridden method ('mixedInMethod').
+//   int mixedInMethod();
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  method extendedMethod() → core::num
+    return 0;
+}
+class Mixin extends core::Object {
+  synthetic constructor •() → self::Mixin
+    : super core::Object::•()
+    ;
+  method mixedInMethod() → core::num
+    return 0;
+}
+abstract class Interface1 extends core::Object {
+  synthetic constructor •() → self::Interface1
+    : super core::Object::•()
+    ;
+  abstract method extendedMethod() → core::int;
+  abstract method mixedInMethod() → core::int;
+}
+abstract class _Interface2&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Interface2&Super&Mixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub method mixedInMethod() → core::num
+    return super.{self::Mixin::mixedInMethod}();
+}
+abstract class Interface2 extends self::_Interface2&Super&Mixin {
+  synthetic constructor •() → self::Interface2
+    : super self::_Interface2&Super&Mixin::•()
+    ;
+  abstract method extendedMethod() → core::int;
+  abstract method mixedInMethod() → core::int;
+}
+abstract class _ClassExtends&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_ClassExtends&Super&Mixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub method mixedInMethod() → core::num
+    return super.{self::Mixin::mixedInMethod}();
+}
+class ClassExtends extends self::_ClassExtends&Super&Mixin implements self::Interface1 {
+  synthetic constructor •() → self::ClassExtends
+    : super self::_ClassExtends&Super&Mixin::•()
+    ;
+  abstract member-signature method mixedInMethod() → core::int; -> self::Interface1::mixedInMethod
+  abstract member-signature method extendedMethod() → core::int; -> self::Interface1::extendedMethod
+}
+abstract class _ClassExtendsWithNoSuchMethod&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_ClassExtendsWithNoSuchMethod&Super&Mixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub method mixedInMethod() → core::num
+    return super.{self::Mixin::mixedInMethod}();
+}
+class ClassExtendsWithNoSuchMethod extends self::_ClassExtendsWithNoSuchMethod&Super&Mixin implements self::Interface1 {
+  synthetic constructor •() → self::ClassExtendsWithNoSuchMethod
+    : super self::_ClassExtendsWithNoSuchMethod&Super&Mixin::•()
+    ;
+  @#C1
+  method noSuchMethod(core::Invocation invocation) → dynamic {
+    return super.{core::Object::noSuchMethod}(invocation);
+  }
+  abstract member-signature method mixedInMethod() → core::int; -> self::Interface1::mixedInMethod
+  abstract member-signature method extendedMethod() → core::int; -> self::Interface1::extendedMethod
+}
+class ClassImplements extends core::Object implements self::Interface2 {
+  synthetic constructor •() → self::ClassImplements
+    : super core::Object::•()
+    ;
+}
+class ClassImplementsWithNoSuchMethod extends core::Object implements self::Interface2 {
+  synthetic constructor •() → self::ClassImplementsWithNoSuchMethod
+    : super core::Object::•()
+    ;
+  @#C1
+  method noSuchMethod(core::Invocation invocation) → dynamic {
+    return super.{core::Object::noSuchMethod}(invocation);
+  }
+  no-such-method-forwarder method mixedInMethod() → core::int
+    return this.{self::ClassImplementsWithNoSuchMethod::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder method extendedMethod() → core::int
+    return this.{self::ClassImplementsWithNoSuchMethod::noSuchMethod}(new core::_InvocationMirror::_withType(#C6, 0, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+}
+abstract class _ClassDeclaresExtends&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_ClassDeclaresExtends&Super&Mixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub method mixedInMethod() → core::num
+    return super.{self::Mixin::mixedInMethod}();
+}
+class ClassDeclaresExtends extends self::_ClassDeclaresExtends&Super&Mixin {
+  synthetic constructor •() → self::ClassDeclaresExtends
+    : super self::_ClassDeclaresExtends&Super&Mixin::•()
+    ;
+  abstract method extendedMethod() → core::int;
+  abstract method mixedInMethod() → core::int;
+}
+abstract class _ClassDeclaresExtendsWithNoSuchMethod&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_ClassDeclaresExtendsWithNoSuchMethod&Super&Mixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub method mixedInMethod() → core::num
+    return super.{self::Mixin::mixedInMethod}();
+}
+class ClassDeclaresExtendsWithNoSuchMethod extends self::_ClassDeclaresExtendsWithNoSuchMethod&Super&Mixin {
+  synthetic constructor •() → self::ClassDeclaresExtendsWithNoSuchMethod
+    : super self::_ClassDeclaresExtendsWithNoSuchMethod&Super&Mixin::•()
+    ;
+  @#C1
+  method noSuchMethod(core::Invocation invocation) → dynamic {
+    return super.{core::Object::noSuchMethod}(invocation);
+  }
+  abstract method extendedMethod() → core::int;
+  abstract method mixedInMethod() → core::int;
+}
+class ClassDeclaresImplementsWithNoSuchMethod extends core::Object implements self::Super, self::Mixin {
+  synthetic constructor •() → self::ClassDeclaresImplementsWithNoSuchMethod
+    : super core::Object::•()
+    ;
+  @#C1
+  method noSuchMethod(core::Invocation invocation) → dynamic {
+    return super.{core::Object::noSuchMethod}(invocation);
+  }
+  no-such-method-forwarder method extendedMethod() → core::int
+    return this.{self::ClassDeclaresImplementsWithNoSuchMethod::noSuchMethod}(new core::_InvocationMirror::_withType(#C6, 0, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder method mixedInMethod() → core::int
+    return this.{self::ClassDeclaresImplementsWithNoSuchMethod::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 0, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = core::_Override {}
+  #C2 = #mixedInMethod
+  #C3 = <core::Type*>[]
+  #C4 = <dynamic>[]
+  #C5 = <core::Symbol*, dynamic>{)
+  #C6 = #extendedMethod
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature.dart.weak.modular.expect
new file mode 100644
index 0000000..f789cb9
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature.dart.weak.modular.expect
@@ -0,0 +1,185 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature.dart:11:7: Error: The non-abstract class 'ConcreteSub' is missing implementations for these members:
+//  - Interface1.extendedAbstractImplementedMethod
+//  - Interface1.implementedMethod
+//  - Interface1.implementedMultipleMethod
+//  - Interface2.implementedMultipleMethod
+//  - Super.extendedAbstractImplementedMethod
+//  - Super.extendedAbstractMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteSub extends AbstractClass {}
+//       ^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature_lib.dart:18:8: Context: 'Interface1.extendedAbstractImplementedMethod' is defined here.
+//   void extendedAbstractImplementedMethod(int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature_lib.dart:20:8: Context: 'Interface1.implementedMethod' is defined here.
+//   void implementedMethod(int i) {}
+//        ^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature_lib.dart:22:8: Context: 'Interface1.implementedMultipleMethod' is defined here.
+//   void implementedMultipleMethod(int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature_lib.dart:26:8: Context: 'Interface2.implementedMultipleMethod' is defined here.
+//   void implementedMultipleMethod(int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature_lib.dart:12:8: Context: 'Super.extendedAbstractImplementedMethod' is defined here.
+//   void extendedAbstractImplementedMethod(int i);
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature_lib.dart:8:8: Context: 'Super.extendedAbstractMethod' is defined here.
+//   void extendedAbstractMethod(int i);
+//        ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature.dart:13:7: Error: The non-abstract class 'ConcreteClass' is missing implementations for these members:
+//  - Interface1.extendedAbstractImplementedMethod
+//  - Interface1.implementedMethod
+//  - Interface1.implementedMultipleMethod
+//  - Interface2.implementedMultipleMethod
+//  - Super.extendedAbstractImplementedMethod
+//  - Super.extendedAbstractMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ConcreteClass extends Super implements Interface1, Interface2 {}
+//       ^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature_lib.dart:18:8: Context: 'Interface1.extendedAbstractImplementedMethod' is defined here.
+//   void extendedAbstractImplementedMethod(int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature_lib.dart:20:8: Context: 'Interface1.implementedMethod' is defined here.
+//   void implementedMethod(int i) {}
+//        ^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature_lib.dart:22:8: Context: 'Interface1.implementedMultipleMethod' is defined here.
+//   void implementedMultipleMethod(int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature_lib.dart:26:8: Context: 'Interface2.implementedMultipleMethod' is defined here.
+//   void implementedMultipleMethod(int i) {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature_lib.dart:12:8: Context: 'Super.extendedAbstractImplementedMethod' is defined here.
+//   void extendedAbstractImplementedMethod(int i);
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/member_signature_lib.dart:8:8: Context: 'Super.extendedAbstractMethod' is defined here.
+//   void extendedAbstractMethod(int i);
+//        ^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "member_signature_lib.dart" as mem;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///member_signature_lib.dart";
+
+abstract class AbstractClass extends mem::Super implements mem::Interface1, mem::Interface2 {
+  synthetic constructor •() → self::AbstractClass*
+    : super mem::Super::•()
+    ;
+  abstract member-signature method extendedConcreteMethod(core::int* i) → void; -> mem::Super::extendedConcreteMethod
+  abstract member-signature method extendedConcreteImplementedMethod(core::int* i) → void; -> mem::Super::extendedConcreteImplementedMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature method extendedAbstractMethod(core::int* i) → void; -> mem::Super::extendedAbstractMethod
+  abstract member-signature method extendedAbstractImplementedMethod(core::int* i) → void; -> mem::Super::extendedAbstractImplementedMethod
+  abstract member-signature method implementedMethod(core::int* i) → void; -> mem::Interface1::implementedMethod
+  abstract member-signature method implementedMultipleMethod(core::int* i) → void; -> mem::Interface1::implementedMultipleMethod
+}
+class ConcreteSub extends self::AbstractClass {
+  synthetic constructor •() → self::ConcreteSub*
+    : super self::AbstractClass::•()
+    ;
+}
+class ConcreteClass extends mem::Super implements mem::Interface1, mem::Interface2 {
+  synthetic constructor •() → self::ConcreteClass*
+    : super mem::Super::•()
+    ;
+  abstract member-signature method extendedConcreteMethod(core::int* i) → void; -> mem::Super::extendedConcreteMethod
+  abstract member-signature method extendedConcreteImplementedMethod(core::int* i) → void; -> mem::Super::extendedConcreteImplementedMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature method extendedAbstractMethod(core::int* i) → void; -> mem::Super::extendedAbstractMethod
+  abstract member-signature method extendedAbstractImplementedMethod(core::int* i) → void; -> mem::Super::extendedAbstractImplementedMethod
+  abstract member-signature method implementedMethod(core::int* i) → void; -> mem::Interface1::implementedMethod
+  abstract member-signature method implementedMultipleMethod(core::int* i) → void; -> mem::Interface1::implementedMultipleMethod
+}
+abstract class OptOutInterface extends core::Object {
+  synthetic constructor •() → self::OptOutInterface*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class ClassImplementsOptOut extends core::Object implements self::OptOutInterface {
+  synthetic constructor •() → self::ClassImplementsOptOut*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as mem;
+import "dart:core" as core;
+
+abstract class Super extends core::Object {
+  synthetic constructor •() → mem::Super
+    : super core::Object::•()
+    ;
+  method extendedConcreteMethod(core::int i) → void {}
+  abstract method extendedAbstractMethod(core::int i) → void;
+  method extendedConcreteImplementedMethod(core::int i) → void {}
+  abstract method extendedAbstractImplementedMethod(core::int i) → void;
+}
+abstract class Interface1 extends core::Object {
+  synthetic constructor •() → mem::Interface1
+    : super core::Object::•()
+    ;
+  method extendedConcreteImplementedMethod(core::int i) → void {}
+  method extendedAbstractImplementedMethod(core::int i) → void {}
+  method implementedMethod(core::int i) → void {}
+  method implementedMultipleMethod(core::int i) → void {}
+}
+abstract class Interface2 extends core::Object {
+  synthetic constructor •() → mem::Interface2
+    : super core::Object::•()
+    ;
+  method implementedMultipleMethod(core::int i) → void {}
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart.weak.modular.expect
new file mode 100644
index 0000000..185fc0d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart.weak.modular.expect
@@ -0,0 +1,239 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:5:7: Error: The non-abstract class 'Super' is missing implementations for these members:
+//  - Super.extendedAbstractField
+//  - Super.extendedAbstractField=
+//  - Super.extendedAbstractMixedInAbstractField
+//  - Super.extendedAbstractMixedInAbstractField=
+//  - Super.extendedAbstractMixedInConcreteField
+//  - Super.extendedAbstractMixedInConcreteField=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Super {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:8:16: Context: 'Super.extendedAbstractField' is defined here.
+//   abstract int extendedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:8:16: Context: 'Super.extendedAbstractField=' is defined here.
+//   abstract int extendedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:16:16: Context: 'Super.extendedAbstractMixedInAbstractField' is defined here.
+//   abstract int extendedAbstractMixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:16:16: Context: 'Super.extendedAbstractMixedInAbstractField=' is defined here.
+//   abstract int extendedAbstractMixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:12:16: Context: 'Super.extendedAbstractMixedInConcreteField' is defined here.
+//   abstract int extendedAbstractMixedInConcreteField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:12:16: Context: 'Super.extendedAbstractMixedInConcreteField=' is defined here.
+//   abstract int extendedAbstractMixedInConcreteField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:19:7: Error: The non-abstract class 'Mixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractField
+//  - Mixin.extendedAbstractMixedInAbstractField=
+//  - Mixin.extendedConcreteMixedInAbstractField
+//  - Mixin.extendedConcreteMixedInAbstractField=
+//  - Mixin.mixedInAbstractField
+//  - Mixin.mixedInAbstractField=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Mixin {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:30:16: Context: 'Mixin.extendedAbstractMixedInAbstractField' is defined here.
+//   abstract int extendedAbstractMixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:30:16: Context: 'Mixin.extendedAbstractMixedInAbstractField=' is defined here.
+//   abstract int extendedAbstractMixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:28:16: Context: 'Mixin.extendedConcreteMixedInAbstractField' is defined here.
+//   abstract int extendedConcreteMixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:28:16: Context: 'Mixin.extendedConcreteMixedInAbstractField=' is defined here.
+//   abstract int extendedConcreteMixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:22:16: Context: 'Mixin.mixedInAbstractField' is defined here.
+//   abstract int mixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:22:16: Context: 'Mixin.mixedInAbstractField=' is defined here.
+//   abstract int mixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:33:7: Error: The non-abstract class 'ClassMixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractField
+//  - Mixin.extendedAbstractMixedInAbstractField=
+//  - Mixin.mixedInAbstractField
+//  - Mixin.mixedInAbstractField=
+//  - Super.extendedAbstractField
+//  - Super.extendedAbstractField=
+//  - Super.extendedAbstractMixedInAbstractField
+//  - Super.extendedAbstractMixedInAbstractField=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ClassMixin extends Super with Mixin {}
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:30:16: Context: 'Mixin.extendedAbstractMixedInAbstractField' is defined here.
+//   abstract int extendedAbstractMixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:30:16: Context: 'Mixin.extendedAbstractMixedInAbstractField=' is defined here.
+//   abstract int extendedAbstractMixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:22:16: Context: 'Mixin.mixedInAbstractField' is defined here.
+//   abstract int mixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:22:16: Context: 'Mixin.mixedInAbstractField=' is defined here.
+//   abstract int mixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:8:16: Context: 'Super.extendedAbstractField' is defined here.
+//   abstract int extendedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:8:16: Context: 'Super.extendedAbstractField=' is defined here.
+//   abstract int extendedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:16:16: Context: 'Super.extendedAbstractMixedInAbstractField' is defined here.
+//   abstract int extendedAbstractMixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:16:16: Context: 'Super.extendedAbstractMixedInAbstractField=' is defined here.
+//   abstract int extendedAbstractMixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:35:7: Error: The non-abstract class 'NamedMixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractField
+//  - Mixin.extendedAbstractMixedInAbstractField=
+//  - Mixin.mixedInAbstractField
+//  - Mixin.mixedInAbstractField=
+//  - Super.extendedAbstractField
+//  - Super.extendedAbstractField=
+//  - Super.extendedAbstractMixedInAbstractField
+//  - Super.extendedAbstractMixedInAbstractField=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class NamedMixin = Super with Mixin;
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:30:16: Context: 'Mixin.extendedAbstractMixedInAbstractField' is defined here.
+//   abstract int extendedAbstractMixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:30:16: Context: 'Mixin.extendedAbstractMixedInAbstractField=' is defined here.
+//   abstract int extendedAbstractMixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:22:16: Context: 'Mixin.mixedInAbstractField' is defined here.
+//   abstract int mixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:22:16: Context: 'Mixin.mixedInAbstractField=' is defined here.
+//   abstract int mixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:8:16: Context: 'Super.extendedAbstractField' is defined here.
+//   abstract int extendedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:8:16: Context: 'Super.extendedAbstractField=' is defined here.
+//   abstract int extendedAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:16:16: Context: 'Super.extendedAbstractMixedInAbstractField' is defined here.
+//   abstract int extendedAbstractMixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_field.dart:16:16: Context: 'Super.extendedAbstractMixedInAbstractField=' is defined here.
+//   abstract int extendedAbstractMixedInAbstractField;
+//                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  field core::int extendedConcreteField = 0;
+  field core::int extendedConcreteMixedInConcreteField = 0;
+  field core::int extendedConcreteMixedInAbstractField = 0;
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  abstract get extendedAbstractField() → core::int;
+  abstract set extendedAbstractField(core::int #externalFieldValue) → void;
+  abstract get extendedAbstractMixedInConcreteField() → core::int;
+  abstract set extendedAbstractMixedInConcreteField(core::int #externalFieldValue) → void;
+  abstract get extendedAbstractMixedInAbstractField() → core::int;
+  abstract set extendedAbstractMixedInAbstractField(core::int #externalFieldValue) → void;
+}
+class Mixin extends core::Object {
+  field core::int mixedInConcreteField = 0;
+  field core::int extendedConcreteMixedInConcreteField = 0;
+  field core::int extendedAbstractMixedInConcreteField = 0;
+  synthetic constructor •() → self::Mixin
+    : super core::Object::•()
+    ;
+  abstract get mixedInAbstractField() → core::int;
+  abstract set mixedInAbstractField(core::int #externalFieldValue) → void;
+  abstract get extendedConcreteMixedInAbstractField() → core::int;
+  abstract set extendedConcreteMixedInAbstractField(core::int #externalFieldValue) → void;
+  abstract get extendedAbstractMixedInAbstractField() → core::int;
+  abstract set extendedAbstractMixedInAbstractField(core::int #externalFieldValue) → void;
+}
+abstract class _ClassMixin&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_ClassMixin&Super&Mixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub get mixedInConcreteField() → core::int
+    return super.{self::Mixin::mixedInConcreteField};
+  mixin-super-stub set mixedInConcreteField(core::int value) → void
+    return super.{self::Mixin::mixedInConcreteField} = value;
+  abstract mixin-stub get mixedInAbstractField() → core::int; -> self::Mixin::mixedInAbstractField
+  abstract mixin-stub set mixedInAbstractField(core::int #externalFieldValue) → void; -> self::Mixin::mixedInAbstractField
+  mixin-super-stub get extendedConcreteMixedInConcreteField() → core::int
+    return super.{self::Mixin::extendedConcreteMixedInConcreteField};
+  mixin-super-stub set extendedConcreteMixedInConcreteField(core::int value) → void
+    return super.{self::Mixin::extendedConcreteMixedInConcreteField} = value;
+  mixin-super-stub get extendedAbstractMixedInConcreteField() → core::int
+    return super.{self::Mixin::extendedAbstractMixedInConcreteField};
+  mixin-super-stub set extendedAbstractMixedInConcreteField(core::int value) → void
+    return super.{self::Mixin::extendedAbstractMixedInConcreteField} = value;
+  abstract mixin-stub get extendedConcreteMixedInAbstractField() → core::int; -> self::Mixin::extendedConcreteMixedInAbstractField
+  abstract mixin-stub set extendedConcreteMixedInAbstractField(core::int #externalFieldValue) → void; -> self::Mixin::extendedConcreteMixedInAbstractField
+  abstract mixin-stub get extendedAbstractMixedInAbstractField() → core::int; -> self::Mixin::extendedAbstractMixedInAbstractField
+  abstract mixin-stub set extendedAbstractMixedInAbstractField(core::int #externalFieldValue) → void; -> self::Mixin::extendedAbstractMixedInAbstractField
+}
+class ClassMixin extends self::_ClassMixin&Super&Mixin {
+  synthetic constructor •() → self::ClassMixin
+    : super self::_ClassMixin&Super&Mixin::•()
+    ;
+}
+class NamedMixin = self::Super with self::Mixin {
+  synthetic constructor •() → self::NamedMixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub get mixedInConcreteField() → core::int
+    return super.{self::Mixin::mixedInConcreteField};
+  mixin-super-stub set mixedInConcreteField(core::int value) → void
+    return super.{self::Mixin::mixedInConcreteField} = value;
+  abstract mixin-stub get mixedInAbstractField() → core::int; -> self::Mixin::mixedInAbstractField
+  abstract mixin-stub set mixedInAbstractField(core::int #externalFieldValue) → void; -> self::Mixin::mixedInAbstractField
+  mixin-super-stub get extendedConcreteMixedInConcreteField() → core::int
+    return super.{self::Mixin::extendedConcreteMixedInConcreteField};
+  mixin-super-stub set extendedConcreteMixedInConcreteField(core::int value) → void
+    return super.{self::Mixin::extendedConcreteMixedInConcreteField} = value;
+  mixin-super-stub get extendedAbstractMixedInConcreteField() → core::int
+    return super.{self::Mixin::extendedAbstractMixedInConcreteField};
+  mixin-super-stub set extendedAbstractMixedInConcreteField(core::int value) → void
+    return super.{self::Mixin::extendedAbstractMixedInConcreteField} = value;
+  abstract mixin-stub get extendedConcreteMixedInAbstractField() → core::int; -> self::Mixin::extendedConcreteMixedInAbstractField
+  abstract mixin-stub set extendedConcreteMixedInAbstractField(core::int #externalFieldValue) → void; -> self::Mixin::extendedConcreteMixedInAbstractField
+  abstract mixin-stub get extendedAbstractMixedInAbstractField() → core::int; -> self::Mixin::extendedAbstractMixedInAbstractField
+  abstract mixin-stub set extendedAbstractMixedInAbstractField(core::int #externalFieldValue) → void; -> self::Mixin::extendedAbstractMixedInAbstractField
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart.weak.modular.expect
new file mode 100644
index 0000000..aa5c0aa6
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart.weak.modular.expect
@@ -0,0 +1,159 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:5:7: Error: The non-abstract class 'Super' is missing implementations for these members:
+//  - Super.extendedAbstractField
+//  - Super.extendedAbstractMixedInAbstractField
+//  - Super.extendedAbstractMixedInConcreteField
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Super {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:8:22: Context: 'Super.extendedAbstractField' is defined here.
+//   abstract final int extendedAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:16:22: Context: 'Super.extendedAbstractMixedInAbstractField' is defined here.
+//   abstract final int extendedAbstractMixedInAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:12:22: Context: 'Super.extendedAbstractMixedInConcreteField' is defined here.
+//   abstract final int extendedAbstractMixedInConcreteField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:19:7: Error: The non-abstract class 'Mixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractField
+//  - Mixin.extendedConcreteMixedInAbstractField
+//  - Mixin.mixedInAbstractField
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Mixin {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:30:22: Context: 'Mixin.extendedAbstractMixedInAbstractField' is defined here.
+//   abstract final int extendedAbstractMixedInAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:28:22: Context: 'Mixin.extendedConcreteMixedInAbstractField' is defined here.
+//   abstract final int extendedConcreteMixedInAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:22:22: Context: 'Mixin.mixedInAbstractField' is defined here.
+//   abstract final int mixedInAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:33:7: Error: The non-abstract class 'ClassMixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractField
+//  - Mixin.mixedInAbstractField
+//  - Super.extendedAbstractField
+//  - Super.extendedAbstractMixedInAbstractField
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ClassMixin extends Super with Mixin {}
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:30:22: Context: 'Mixin.extendedAbstractMixedInAbstractField' is defined here.
+//   abstract final int extendedAbstractMixedInAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:22:22: Context: 'Mixin.mixedInAbstractField' is defined here.
+//   abstract final int mixedInAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:8:22: Context: 'Super.extendedAbstractField' is defined here.
+//   abstract final int extendedAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:16:22: Context: 'Super.extendedAbstractMixedInAbstractField' is defined here.
+//   abstract final int extendedAbstractMixedInAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:35:7: Error: The non-abstract class 'NamedMixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractField
+//  - Mixin.mixedInAbstractField
+//  - Super.extendedAbstractField
+//  - Super.extendedAbstractMixedInAbstractField
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class NamedMixin = Super with Mixin;
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:30:22: Context: 'Mixin.extendedAbstractMixedInAbstractField' is defined here.
+//   abstract final int extendedAbstractMixedInAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:22:22: Context: 'Mixin.mixedInAbstractField' is defined here.
+//   abstract final int mixedInAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:8:22: Context: 'Super.extendedAbstractField' is defined here.
+//   abstract final int extendedAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_final_field.dart:16:22: Context: 'Super.extendedAbstractMixedInAbstractField' is defined here.
+//   abstract final int extendedAbstractMixedInAbstractField;
+//                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  final field core::int extendedConcreteField = 0;
+  final field core::int extendedConcreteMixedInConcreteField = 0;
+  final field core::int extendedConcreteMixedInAbstractField = 0;
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  abstract get extendedAbstractField() → core::int;
+  abstract get extendedAbstractMixedInConcreteField() → core::int;
+  abstract get extendedAbstractMixedInAbstractField() → core::int;
+}
+class Mixin extends core::Object {
+  final field core::int mixedInConcreteField = 0;
+  final field core::int extendedConcreteMixedInConcreteField = 0;
+  final field core::int extendedAbstractMixedInConcreteField = 0;
+  synthetic constructor •() → self::Mixin
+    : super core::Object::•()
+    ;
+  abstract get mixedInAbstractField() → core::int;
+  abstract get extendedConcreteMixedInAbstractField() → core::int;
+  abstract get extendedAbstractMixedInAbstractField() → core::int;
+}
+abstract class _ClassMixin&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_ClassMixin&Super&Mixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub get mixedInConcreteField() → core::int
+    return super.{self::Mixin::mixedInConcreteField};
+  mixin-super-stub get extendedConcreteMixedInConcreteField() → core::int
+    return super.{self::Mixin::extendedConcreteMixedInConcreteField};
+  mixin-super-stub get extendedAbstractMixedInConcreteField() → core::int
+    return super.{self::Mixin::extendedAbstractMixedInConcreteField};
+  abstract mixin-stub get extendedConcreteMixedInAbstractField() → core::int; -> self::Mixin::extendedConcreteMixedInAbstractField
+  abstract mixin-stub get mixedInAbstractField() → core::int; -> self::Mixin::mixedInAbstractField
+  abstract mixin-stub get extendedAbstractMixedInAbstractField() → core::int; -> self::Mixin::extendedAbstractMixedInAbstractField
+}
+class ClassMixin extends self::_ClassMixin&Super&Mixin {
+  synthetic constructor •() → self::ClassMixin
+    : super self::_ClassMixin&Super&Mixin::•()
+    ;
+}
+class NamedMixin = self::Super with self::Mixin {
+  synthetic constructor •() → self::NamedMixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub get mixedInConcreteField() → core::int
+    return super.{self::Mixin::mixedInConcreteField};
+  mixin-super-stub get extendedConcreteMixedInConcreteField() → core::int
+    return super.{self::Mixin::extendedConcreteMixedInConcreteField};
+  mixin-super-stub get extendedAbstractMixedInConcreteField() → core::int
+    return super.{self::Mixin::extendedAbstractMixedInConcreteField};
+  abstract mixin-stub get extendedConcreteMixedInAbstractField() → core::int; -> self::Mixin::extendedConcreteMixedInAbstractField
+  abstract mixin-stub get mixedInAbstractField() → core::int; -> self::Mixin::mixedInAbstractField
+  abstract mixin-stub get extendedAbstractMixedInAbstractField() → core::int; -> self::Mixin::extendedAbstractMixedInAbstractField
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..09d72f2
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart.weak.modular.expect
@@ -0,0 +1,165 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:5:7: Error: The non-abstract class 'Super' is missing implementations for these members:
+//  - Super.extendedAbstractGetter
+//  - Super.extendedAbstractMixedInAbstractGetter
+//  - Super.extendedAbstractMixedInConcreteGetter
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Super {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:8:11: Context: 'Super.extendedAbstractGetter' is defined here.
+//   int get extendedAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:16:11: Context: 'Super.extendedAbstractMixedInAbstractGetter' is defined here.
+//   int get extendedAbstractMixedInAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:12:11: Context: 'Super.extendedAbstractMixedInConcreteGetter' is defined here.
+//   int get extendedAbstractMixedInConcreteGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:19:7: Error: The non-abstract class 'Mixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractGetter
+//  - Mixin.extendedConcreteMixedInAbstractGetter
+//  - Mixin.mixedInAbstractGetter
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Mixin {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:30:11: Context: 'Mixin.extendedAbstractMixedInAbstractGetter' is defined here.
+//   int get extendedAbstractMixedInAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:28:11: Context: 'Mixin.extendedConcreteMixedInAbstractGetter' is defined here.
+//   int get extendedConcreteMixedInAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:22:11: Context: 'Mixin.mixedInAbstractGetter' is defined here.
+//   int get mixedInAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:33:7: Error: The non-abstract class 'ClassMixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractGetter
+//  - Mixin.mixedInAbstractGetter
+//  - Super.extendedAbstractGetter
+//  - Super.extendedAbstractMixedInAbstractGetter
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ClassMixin extends Super with Mixin {}
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:30:11: Context: 'Mixin.extendedAbstractMixedInAbstractGetter' is defined here.
+//   int get extendedAbstractMixedInAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:22:11: Context: 'Mixin.mixedInAbstractGetter' is defined here.
+//   int get mixedInAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:8:11: Context: 'Super.extendedAbstractGetter' is defined here.
+//   int get extendedAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:16:11: Context: 'Super.extendedAbstractMixedInAbstractGetter' is defined here.
+//   int get extendedAbstractMixedInAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:35:7: Error: The non-abstract class 'NamedMixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractGetter
+//  - Mixin.mixedInAbstractGetter
+//  - Super.extendedAbstractGetter
+//  - Super.extendedAbstractMixedInAbstractGetter
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class NamedMixin = Super with Mixin;
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:30:11: Context: 'Mixin.extendedAbstractMixedInAbstractGetter' is defined here.
+//   int get extendedAbstractMixedInAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:22:11: Context: 'Mixin.mixedInAbstractGetter' is defined here.
+//   int get mixedInAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:8:11: Context: 'Super.extendedAbstractGetter' is defined here.
+//   int get extendedAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_getter.dart:16:11: Context: 'Super.extendedAbstractMixedInAbstractGetter' is defined here.
+//   int get extendedAbstractMixedInAbstractGetter;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  get extendedConcreteGetter() → core::int
+    return 0;
+  abstract get extendedAbstractGetter() → core::int;
+  get extendedConcreteMixedInConcreteGetter() → core::int
+    return 0;
+  abstract get extendedAbstractMixedInConcreteGetter() → core::int;
+  get extendedConcreteMixedInAbstractGetter() → core::int
+    return 0;
+  abstract get extendedAbstractMixedInAbstractGetter() → core::int;
+}
+class Mixin extends core::Object {
+  synthetic constructor •() → self::Mixin
+    : super core::Object::•()
+    ;
+  get mixedInConcreteGetter() → core::int
+    return 0;
+  abstract get mixedInAbstractGetter() → core::int;
+  get extendedConcreteMixedInConcreteGetter() → core::int
+    return 0;
+  get extendedAbstractMixedInConcreteGetter() → core::int
+    return 0;
+  abstract get extendedConcreteMixedInAbstractGetter() → core::int;
+  abstract get extendedAbstractMixedInAbstractGetter() → core::int;
+}
+abstract class _ClassMixin&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_ClassMixin&Super&Mixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub get mixedInConcreteGetter() → core::int
+    return super.{self::Mixin::mixedInConcreteGetter};
+  mixin-super-stub get extendedConcreteMixedInConcreteGetter() → core::int
+    return super.{self::Mixin::extendedConcreteMixedInConcreteGetter};
+  mixin-super-stub get extendedAbstractMixedInConcreteGetter() → core::int
+    return super.{self::Mixin::extendedAbstractMixedInConcreteGetter};
+  abstract mixin-stub get extendedConcreteMixedInAbstractGetter() → core::int; -> self::Mixin::extendedConcreteMixedInAbstractGetter
+  abstract mixin-stub get mixedInAbstractGetter() → core::int; -> self::Mixin::mixedInAbstractGetter
+  abstract mixin-stub get extendedAbstractMixedInAbstractGetter() → core::int; -> self::Mixin::extendedAbstractMixedInAbstractGetter
+}
+class ClassMixin extends self::_ClassMixin&Super&Mixin {
+  synthetic constructor •() → self::ClassMixin
+    : super self::_ClassMixin&Super&Mixin::•()
+    ;
+}
+class NamedMixin = self::Super with self::Mixin {
+  synthetic constructor •() → self::NamedMixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub get mixedInConcreteGetter() → core::int
+    return super.{self::Mixin::mixedInConcreteGetter};
+  mixin-super-stub get extendedConcreteMixedInConcreteGetter() → core::int
+    return super.{self::Mixin::extendedConcreteMixedInConcreteGetter};
+  mixin-super-stub get extendedAbstractMixedInConcreteGetter() → core::int
+    return super.{self::Mixin::extendedAbstractMixedInConcreteGetter};
+  abstract mixin-stub get extendedConcreteMixedInAbstractGetter() → core::int; -> self::Mixin::extendedConcreteMixedInAbstractGetter
+  abstract mixin-stub get mixedInAbstractGetter() → core::int; -> self::Mixin::mixedInAbstractGetter
+  abstract mixin-stub get extendedAbstractMixedInAbstractGetter() → core::int; -> self::Mixin::extendedAbstractMixedInAbstractGetter
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart.weak.modular.expect
new file mode 100644
index 0000000..2c5b765
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart.weak.modular.expect
@@ -0,0 +1,159 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:5:7: Error: The non-abstract class 'Super' is missing implementations for these members:
+//  - Super.extendedAbstractMethod
+//  - Super.extendedAbstractMixedInAbstractMethod
+//  - Super.extendedAbstractMixedInConcreteMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Super {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:8:8: Context: 'Super.extendedAbstractMethod' is defined here.
+//   void extendedAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:16:8: Context: 'Super.extendedAbstractMixedInAbstractMethod' is defined here.
+//   void extendedAbstractMixedInAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:12:8: Context: 'Super.extendedAbstractMixedInConcreteMethod' is defined here.
+//   void extendedAbstractMixedInConcreteMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:19:7: Error: The non-abstract class 'Mixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractMethod
+//  - Mixin.extendedConcreteMixedInAbstractMethod
+//  - Mixin.mixedInAbstractMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Mixin {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:30:8: Context: 'Mixin.extendedAbstractMixedInAbstractMethod' is defined here.
+//   void extendedAbstractMixedInAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:28:8: Context: 'Mixin.extendedConcreteMixedInAbstractMethod' is defined here.
+//   void extendedConcreteMixedInAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:22:8: Context: 'Mixin.mixedInAbstractMethod' is defined here.
+//   void mixedInAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:33:7: Error: The non-abstract class 'ClassMixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractMethod
+//  - Mixin.mixedInAbstractMethod
+//  - Super.extendedAbstractMethod
+//  - Super.extendedAbstractMixedInAbstractMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ClassMixin extends Super with Mixin {}
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:30:8: Context: 'Mixin.extendedAbstractMixedInAbstractMethod' is defined here.
+//   void extendedAbstractMixedInAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:22:8: Context: 'Mixin.mixedInAbstractMethod' is defined here.
+//   void mixedInAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:8:8: Context: 'Super.extendedAbstractMethod' is defined here.
+//   void extendedAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:16:8: Context: 'Super.extendedAbstractMixedInAbstractMethod' is defined here.
+//   void extendedAbstractMixedInAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:35:7: Error: The non-abstract class 'NamedMixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractMethod
+//  - Mixin.mixedInAbstractMethod
+//  - Super.extendedAbstractMethod
+//  - Super.extendedAbstractMixedInAbstractMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class NamedMixin = Super with Mixin;
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:30:8: Context: 'Mixin.extendedAbstractMixedInAbstractMethod' is defined here.
+//   void extendedAbstractMixedInAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:22:8: Context: 'Mixin.mixedInAbstractMethod' is defined here.
+//   void mixedInAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:8:8: Context: 'Super.extendedAbstractMethod' is defined here.
+//   void extendedAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_method.dart:16:8: Context: 'Super.extendedAbstractMixedInAbstractMethod' is defined here.
+//   void extendedAbstractMixedInAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  method extendedConcreteMethod() → void {}
+  abstract method extendedAbstractMethod() → void;
+  method extendedConcreteMixedInConcreteMethod() → void {}
+  abstract method extendedAbstractMixedInConcreteMethod() → void;
+  method extendedConcreteMixedInAbstractMethod() → void {}
+  abstract method extendedAbstractMixedInAbstractMethod() → void;
+}
+class Mixin extends core::Object {
+  synthetic constructor •() → self::Mixin
+    : super core::Object::•()
+    ;
+  method mixedInConcreteMethod() → void {}
+  abstract method mixedInAbstractMethod() → void;
+  method extendedConcreteMixedInConcreteMethod() → void {}
+  method extendedAbstractMixedInConcreteMethod() → void {}
+  abstract method extendedConcreteMixedInAbstractMethod() → void;
+  abstract method extendedAbstractMixedInAbstractMethod() → void;
+}
+abstract class _ClassMixin&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_ClassMixin&Super&Mixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub method mixedInConcreteMethod() → void
+    return super.{self::Mixin::mixedInConcreteMethod}();
+  mixin-super-stub method extendedConcreteMixedInConcreteMethod() → void
+    return super.{self::Mixin::extendedConcreteMixedInConcreteMethod}();
+  mixin-super-stub method extendedAbstractMixedInConcreteMethod() → void
+    return super.{self::Mixin::extendedAbstractMixedInConcreteMethod}();
+  abstract mixin-stub method extendedConcreteMixedInAbstractMethod() → void; -> self::Mixin::extendedConcreteMixedInAbstractMethod
+  abstract mixin-stub method mixedInAbstractMethod() → void; -> self::Mixin::mixedInAbstractMethod
+  abstract mixin-stub method extendedAbstractMixedInAbstractMethod() → void; -> self::Mixin::extendedAbstractMixedInAbstractMethod
+}
+class ClassMixin extends self::_ClassMixin&Super&Mixin {
+  synthetic constructor •() → self::ClassMixin
+    : super self::_ClassMixin&Super&Mixin::•()
+    ;
+}
+class NamedMixin = self::Super with self::Mixin {
+  synthetic constructor •() → self::NamedMixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub method mixedInConcreteMethod() → void
+    return super.{self::Mixin::mixedInConcreteMethod}();
+  mixin-super-stub method extendedConcreteMixedInConcreteMethod() → void
+    return super.{self::Mixin::extendedConcreteMixedInConcreteMethod}();
+  mixin-super-stub method extendedAbstractMixedInConcreteMethod() → void
+    return super.{self::Mixin::extendedAbstractMixedInConcreteMethod}();
+  abstract mixin-stub method extendedConcreteMixedInAbstractMethod() → void; -> self::Mixin::extendedConcreteMixedInAbstractMethod
+  abstract mixin-stub method mixedInAbstractMethod() → void; -> self::Mixin::mixedInAbstractMethod
+  abstract mixin-stub method extendedAbstractMixedInAbstractMethod() → void; -> self::Mixin::extendedAbstractMixedInAbstractMethod
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart.weak.modular.expect
new file mode 100644
index 0000000..77883ed
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart.weak.modular.expect
@@ -0,0 +1,249 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:5:7: Error: The non-abstract class 'Super' is missing implementations for these members:
+//  - Super.extendedAbstractMethod
+//  - Super.extendedAbstractMixedInAbstractMethod
+//  - Super.extendedAbstractMixedInConcreteMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Super {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:8:8: Context: 'Super.extendedAbstractMethod' is defined here.
+//   void extendedAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:16:8: Context: 'Super.extendedAbstractMixedInAbstractMethod' is defined here.
+//   void extendedAbstractMixedInAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:12:8: Context: 'Super.extendedAbstractMixedInConcreteMethod' is defined here.
+//   void extendedAbstractMixedInConcreteMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:19:7: Error: The non-abstract class 'Mixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractMethod
+//  - Mixin.extendedConcreteMixedInAbstractMethod
+//  - Mixin.mixedInAbstractMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Mixin {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:30:8: Context: 'Mixin.extendedAbstractMixedInAbstractMethod' is defined here.
+//   void extendedAbstractMixedInAbstractMethod(int i);
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:28:8: Context: 'Mixin.extendedConcreteMixedInAbstractMethod' is defined here.
+//   void extendedConcreteMixedInAbstractMethod(int i);
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:22:8: Context: 'Mixin.mixedInAbstractMethod' is defined here.
+//   void mixedInAbstractMethod(int i);
+//        ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:33:7: Error: The non-abstract class 'ClassMixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractMethod
+//  - Mixin.mixedInAbstractMethod
+//  - Super.extendedAbstractMethod
+//  - Super.extendedAbstractMixedInAbstractMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ClassMixin extends Super with Mixin {}
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:30:8: Context: 'Mixin.extendedAbstractMixedInAbstractMethod' is defined here.
+//   void extendedAbstractMixedInAbstractMethod(int i);
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:22:8: Context: 'Mixin.mixedInAbstractMethod' is defined here.
+//   void mixedInAbstractMethod(int i);
+//        ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:8:8: Context: 'Super.extendedAbstractMethod' is defined here.
+//   void extendedAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:16:8: Context: 'Super.extendedAbstractMixedInAbstractMethod' is defined here.
+//   void extendedAbstractMixedInAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:35:7: Error: The non-abstract class 'NamedMixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractMethod
+//  - Mixin.mixedInAbstractMethod
+//  - Super.extendedAbstractMethod
+//  - Super.extendedAbstractMixedInAbstractMethod
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class NamedMixin = Super with Mixin;
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:30:8: Context: 'Mixin.extendedAbstractMixedInAbstractMethod' is defined here.
+//   void extendedAbstractMixedInAbstractMethod(int i);
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:22:8: Context: 'Mixin.mixedInAbstractMethod' is defined here.
+//   void mixedInAbstractMethod(int i);
+//        ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:8:8: Context: 'Super.extendedAbstractMethod' is defined here.
+//   void extendedAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:16:8: Context: 'Super.extendedAbstractMixedInAbstractMethod' is defined here.
+//   void extendedAbstractMixedInAbstractMethod();
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:33:7: Error: Applying the mixin 'Mixin' to 'Super' introduces an erroneous override of 'extendedConcreteMixedInConcreteMethod'.
+// class ClassMixin extends Super with Mixin {}
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:24:8: Context: The method 'Mixin.extendedConcreteMixedInConcreteMethod' has more required arguments than those of overridden method 'Super.extendedConcreteMixedInConcreteMethod'.
+//   void extendedConcreteMixedInConcreteMethod(int i) {}
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:10:8: Context: This is the overridden method ('extendedConcreteMixedInConcreteMethod').
+//   void extendedConcreteMixedInConcreteMethod() {}
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:33:7: Error: Applying the mixin 'Mixin' to 'Super' introduces an erroneous override of 'extendedAbstractMixedInConcreteMethod'.
+// class ClassMixin extends Super with Mixin {}
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:26:8: Context: The method 'Mixin.extendedAbstractMixedInConcreteMethod' has more required arguments than those of overridden method 'Super.extendedAbstractMixedInConcreteMethod'.
+//   void extendedAbstractMixedInConcreteMethod(int i) {}
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:12:8: Context: This is the overridden method ('extendedAbstractMixedInConcreteMethod').
+//   void extendedAbstractMixedInConcreteMethod();
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:33:7: Error: Applying the mixin 'Mixin' to 'Super' introduces an erroneous override of 'extendedConcreteMixedInAbstractMethod'.
+// class ClassMixin extends Super with Mixin {}
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:28:8: Context: The method 'Mixin.extendedConcreteMixedInAbstractMethod' has more required arguments than those of overridden method 'Super.extendedConcreteMixedInAbstractMethod'.
+//   void extendedConcreteMixedInAbstractMethod(int i);
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:14:8: Context: This is the overridden method ('extendedConcreteMixedInAbstractMethod').
+//   void extendedConcreteMixedInAbstractMethod() {}
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:33:7: Error: Applying the mixin 'Mixin' to 'Super' introduces an erroneous override of 'extendedAbstractMixedInAbstractMethod'.
+// class ClassMixin extends Super with Mixin {}
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:30:8: Context: The method 'Mixin.extendedAbstractMixedInAbstractMethod' has more required arguments than those of overridden method 'Super.extendedAbstractMixedInAbstractMethod'.
+//   void extendedAbstractMixedInAbstractMethod(int i);
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:16:8: Context: This is the overridden method ('extendedAbstractMixedInAbstractMethod').
+//   void extendedAbstractMixedInAbstractMethod();
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:33:7: Error: The implementation of 'extendedConcreteMixedInAbstractMethod' in the non-abstract class 'ClassMixin' does not conform to its interface.
+// class ClassMixin extends Super with Mixin {}
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:14:8: Context: The method 'Super.extendedConcreteMixedInAbstractMethod' has fewer positional arguments than those of overridden method 'Super with Mixin.extendedConcreteMixedInAbstractMethod'.
+//   void extendedConcreteMixedInAbstractMethod() {}
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:33:7: Context: This is the overridden method ('extendedConcreteMixedInAbstractMethod').
+// class ClassMixin extends Super with Mixin {}
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:35:7: Error: The mixin application class 'NamedMixin' introduces an erroneous override of 'extendedConcreteMixedInConcreteMethod'.
+// class NamedMixin = Super with Mixin;
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:24:8: Context: The method 'Mixin.extendedConcreteMixedInConcreteMethod' has more required arguments than those of overridden method 'Super.extendedConcreteMixedInConcreteMethod'.
+//   void extendedConcreteMixedInConcreteMethod(int i) {}
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:10:8: Context: This is the overridden method ('extendedConcreteMixedInConcreteMethod').
+//   void extendedConcreteMixedInConcreteMethod() {}
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:35:7: Error: The mixin application class 'NamedMixin' introduces an erroneous override of 'extendedAbstractMixedInConcreteMethod'.
+// class NamedMixin = Super with Mixin;
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:26:8: Context: The method 'Mixin.extendedAbstractMixedInConcreteMethod' has more required arguments than those of overridden method 'Super.extendedAbstractMixedInConcreteMethod'.
+//   void extendedAbstractMixedInConcreteMethod(int i) {}
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:12:8: Context: This is the overridden method ('extendedAbstractMixedInConcreteMethod').
+//   void extendedAbstractMixedInConcreteMethod();
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:35:7: Error: The mixin application class 'NamedMixin' introduces an erroneous override of 'extendedConcreteMixedInAbstractMethod'.
+// class NamedMixin = Super with Mixin;
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:28:8: Context: The method 'Mixin.extendedConcreteMixedInAbstractMethod' has more required arguments than those of overridden method 'Super.extendedConcreteMixedInAbstractMethod'.
+//   void extendedConcreteMixedInAbstractMethod(int i);
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:14:8: Context: This is the overridden method ('extendedConcreteMixedInAbstractMethod').
+//   void extendedConcreteMixedInAbstractMethod() {}
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:35:7: Error: The mixin application class 'NamedMixin' introduces an erroneous override of 'extendedAbstractMixedInAbstractMethod'.
+// class NamedMixin = Super with Mixin;
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:30:8: Context: The method 'Mixin.extendedAbstractMixedInAbstractMethod' has more required arguments than those of overridden method 'Super.extendedAbstractMixedInAbstractMethod'.
+//   void extendedAbstractMixedInAbstractMethod(int i);
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_override.dart:16:8: Context: This is the overridden method ('extendedAbstractMixedInAbstractMethod').
+//   void extendedAbstractMixedInAbstractMethod();
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  method extendedConcreteMethod() → void {}
+  abstract method extendedAbstractMethod() → void;
+  method extendedConcreteMixedInConcreteMethod() → void {}
+  abstract method extendedAbstractMixedInConcreteMethod() → void;
+  method extendedConcreteMixedInAbstractMethod() → void {}
+  abstract method extendedAbstractMixedInAbstractMethod() → void;
+}
+class Mixin extends core::Object {
+  synthetic constructor •() → self::Mixin
+    : super core::Object::•()
+    ;
+  method mixedInConcreteMethod(core::int i) → void {}
+  abstract method mixedInAbstractMethod(core::int i) → void;
+  method extendedConcreteMixedInConcreteMethod(core::int i) → void {}
+  method extendedAbstractMixedInConcreteMethod(core::int i) → void {}
+  abstract method extendedConcreteMixedInAbstractMethod(core::int i) → void;
+  abstract method extendedAbstractMixedInAbstractMethod(core::int i) → void;
+}
+abstract class _ClassMixin&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_ClassMixin&Super&Mixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub method mixedInConcreteMethod(core::int i) → void
+    return super.{self::Mixin::mixedInConcreteMethod}(i);
+  mixin-super-stub method extendedConcreteMixedInConcreteMethod(core::int i) → void
+    return super.{self::Mixin::extendedConcreteMixedInConcreteMethod}(i);
+  mixin-super-stub method extendedAbstractMixedInConcreteMethod(core::int i) → void
+    return super.{self::Mixin::extendedAbstractMixedInConcreteMethod}(i);
+  abstract mixin-stub method extendedConcreteMixedInAbstractMethod(core::int i) → void; -> self::Mixin::extendedConcreteMixedInAbstractMethod
+  abstract mixin-stub method mixedInAbstractMethod(core::int i) → void; -> self::Mixin::mixedInAbstractMethod
+  abstract mixin-stub method extendedAbstractMixedInAbstractMethod(core::int i) → void; -> self::Mixin::extendedAbstractMixedInAbstractMethod
+}
+class ClassMixin extends self::_ClassMixin&Super&Mixin {
+  synthetic constructor •() → self::ClassMixin
+    : super self::_ClassMixin&Super&Mixin::•()
+    ;
+}
+class NamedMixin = self::Super with self::Mixin {
+  synthetic constructor •() → self::NamedMixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub method mixedInConcreteMethod(core::int i) → void
+    return super.{self::Mixin::mixedInConcreteMethod}(i);
+  mixin-super-stub method extendedConcreteMixedInConcreteMethod(core::int i) → void
+    return super.{self::Mixin::extendedConcreteMixedInConcreteMethod}(i);
+  mixin-super-stub method extendedAbstractMixedInConcreteMethod(core::int i) → void
+    return super.{self::Mixin::extendedAbstractMixedInConcreteMethod}(i);
+  abstract mixin-stub method extendedConcreteMixedInAbstractMethod(core::int i) → void; -> self::Mixin::extendedConcreteMixedInAbstractMethod
+  abstract mixin-stub method mixedInAbstractMethod(core::int i) → void; -> self::Mixin::mixedInAbstractMethod
+  abstract mixin-stub method extendedAbstractMixedInAbstractMethod(core::int i) → void; -> self::Mixin::extendedAbstractMixedInAbstractMethod
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..c9a2f79
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart.weak.modular.expect
@@ -0,0 +1,159 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:5:7: Error: The non-abstract class 'Super' is missing implementations for these members:
+//  - Super.extendedAbstractMixedInAbstractSetter=
+//  - Super.extendedAbstractMixedInConcreteSetter=
+//  - Super.extendedAbstractSetter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Super {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:16:12: Context: 'Super.extendedAbstractMixedInAbstractSetter=' is defined here.
+//   void set extendedAbstractMixedInAbstractSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:12:12: Context: 'Super.extendedAbstractMixedInConcreteSetter=' is defined here.
+//   void set extendedAbstractMixedInConcreteSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:8:12: Context: 'Super.extendedAbstractSetter=' is defined here.
+//   void set extendedAbstractSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:19:7: Error: The non-abstract class 'Mixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractSetter=
+//  - Mixin.extendedConcreteMixedInAbstractSetter=
+//  - Mixin.mixedInAbstractSetter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class Mixin {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:30:12: Context: 'Mixin.extendedAbstractMixedInAbstractSetter=' is defined here.
+//   void set extendedAbstractMixedInAbstractSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:28:12: Context: 'Mixin.extendedConcreteMixedInAbstractSetter=' is defined here.
+//   void set extendedConcreteMixedInAbstractSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:22:12: Context: 'Mixin.mixedInAbstractSetter=' is defined here.
+//   void set mixedInAbstractSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:33:7: Error: The non-abstract class 'ClassMixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractSetter=
+//  - Mixin.mixedInAbstractSetter=
+//  - Super.extendedAbstractMixedInAbstractSetter=
+//  - Super.extendedAbstractSetter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class ClassMixin extends Super with Mixin {}
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:30:12: Context: 'Mixin.extendedAbstractMixedInAbstractSetter=' is defined here.
+//   void set extendedAbstractMixedInAbstractSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:22:12: Context: 'Mixin.mixedInAbstractSetter=' is defined here.
+//   void set mixedInAbstractSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:16:12: Context: 'Super.extendedAbstractMixedInAbstractSetter=' is defined here.
+//   void set extendedAbstractMixedInAbstractSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:8:12: Context: 'Super.extendedAbstractSetter=' is defined here.
+//   void set extendedAbstractSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:35:7: Error: The non-abstract class 'NamedMixin' is missing implementations for these members:
+//  - Mixin.extendedAbstractMixedInAbstractSetter=
+//  - Mixin.mixedInAbstractSetter=
+//  - Super.extendedAbstractMixedInAbstractSetter=
+//  - Super.extendedAbstractSetter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class NamedMixin = Super with Mixin;
+//       ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:30:12: Context: 'Mixin.extendedAbstractMixedInAbstractSetter=' is defined here.
+//   void set extendedAbstractMixedInAbstractSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:22:12: Context: 'Mixin.mixedInAbstractSetter=' is defined here.
+//   void set mixedInAbstractSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:16:12: Context: 'Super.extendedAbstractMixedInAbstractSetter=' is defined here.
+//   void set extendedAbstractMixedInAbstractSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/mix_in_setter.dart:8:12: Context: 'Super.extendedAbstractSetter=' is defined here.
+//   void set extendedAbstractSetter(int i);
+//            ^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  set extendedConcreteSetter(core::int i) → void {}
+  abstract set extendedAbstractSetter(core::int i) → void;
+  set extendedConcreteMixedInConcreteSetter(core::int i) → void {}
+  abstract set extendedAbstractMixedInConcreteSetter(core::int i) → void;
+  set extendedConcreteMixedInAbstractSetter(core::int i) → void {}
+  abstract set extendedAbstractMixedInAbstractSetter(core::int i) → void;
+}
+class Mixin extends core::Object {
+  synthetic constructor •() → self::Mixin
+    : super core::Object::•()
+    ;
+  set mixedInConcreteSetter(core::int i) → void {}
+  abstract set mixedInAbstractSetter(core::int i) → void;
+  set extendedConcreteMixedInConcreteSetter(core::int i) → void {}
+  set extendedAbstractMixedInConcreteSetter(core::int i) → void {}
+  abstract set extendedConcreteMixedInAbstractSetter(core::int i) → void;
+  abstract set extendedAbstractMixedInAbstractSetter(core::int i) → void;
+}
+abstract class _ClassMixin&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_ClassMixin&Super&Mixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub set mixedInConcreteSetter(core::int i) → void
+    return super.{self::Mixin::mixedInConcreteSetter} = i;
+  mixin-super-stub set extendedConcreteMixedInConcreteSetter(core::int i) → void
+    return super.{self::Mixin::extendedConcreteMixedInConcreteSetter} = i;
+  mixin-super-stub set extendedAbstractMixedInConcreteSetter(core::int i) → void
+    return super.{self::Mixin::extendedAbstractMixedInConcreteSetter} = i;
+  abstract mixin-stub set extendedConcreteMixedInAbstractSetter(core::int i) → void; -> self::Mixin::extendedConcreteMixedInAbstractSetter
+  abstract mixin-stub set mixedInAbstractSetter(core::int i) → void; -> self::Mixin::mixedInAbstractSetter
+  abstract mixin-stub set extendedAbstractMixedInAbstractSetter(core::int i) → void; -> self::Mixin::extendedAbstractMixedInAbstractSetter
+}
+class ClassMixin extends self::_ClassMixin&Super&Mixin {
+  synthetic constructor •() → self::ClassMixin
+    : super self::_ClassMixin&Super&Mixin::•()
+    ;
+}
+class NamedMixin = self::Super with self::Mixin {
+  synthetic constructor •() → self::NamedMixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub set mixedInConcreteSetter(core::int i) → void
+    return super.{self::Mixin::mixedInConcreteSetter} = i;
+  mixin-super-stub set extendedConcreteMixedInConcreteSetter(core::int i) → void
+    return super.{self::Mixin::extendedConcreteMixedInConcreteSetter} = i;
+  mixin-super-stub set extendedAbstractMixedInConcreteSetter(core::int i) → void
+    return super.{self::Mixin::extendedAbstractMixedInConcreteSetter} = i;
+  abstract mixin-stub set extendedConcreteMixedInAbstractSetter(core::int i) → void; -> self::Mixin::extendedConcreteMixedInAbstractSetter
+  abstract mixin-stub set mixedInAbstractSetter(core::int i) → void; -> self::Mixin::mixedInAbstractSetter
+  abstract mixin-stub set extendedAbstractMixedInAbstractSetter(core::int i) → void; -> self::Mixin::extendedAbstractMixedInAbstractSetter
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/mixin_from_dill/main.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/mixin_from_dill/main.dart.weak.modular.expect
new file mode 100644
index 0000000..d4d8f90
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/mixin_from_dill/main.dart.weak.modular.expect
@@ -0,0 +1,67 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "opt_in_lib1.dart" as opt;
+import "opt_out_lib.dart" as opt2;
+import "opt_in_lib2.dart" as opt3;
+
+import "org-dartlang-testcase:///opt_in_lib1.dart";
+import "org-dartlang-testcase:///opt_in_lib2.dart";
+import "org-dartlang-testcase:///opt_out_lib.dart";
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super*
+    : super core::Object::•()
+    ;
+  get getter() → opt::B*
+    return new opt::B::•();
+  set setter(opt::A* a) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Class1&Super&Mixin1 = self::Super with opt2::Mixin1 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class1&Super&Mixin1*
+    : super self::Super::•()
+    ;
+}
+class Class1 extends self::_Class1&Super&Mixin1 {
+  synthetic constructor •() → self::Class1*
+    : super self::_Class1&Super&Mixin1::•()
+    ;
+}
+abstract class _Class2&Base&Mixin2 = opt::Base with opt3::Mixin2 /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class2&Base&Mixin2*
+    : super opt::Base::•()
+    ;
+  abstract member-signature get _privateGetter() → opt::B*; -> opt::Base::_privateGetter
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature set _privateSetter(opt::A* a) → void; -> opt::Base::_privateSetter
+}
+class Class2 extends self::_Class2&Base&Mixin2 {
+  synthetic constructor •() → self::Class2*
+    : super self::_Class2&Base&Mixin2::•()
+    ;
+}
+static method main() → dynamic {
+  self::Class1* c = new self::Class1::•();
+  c.{self::Super::getter}{opt::B*}.{opt::B::property}{core::int*};
+  c.{self::Super::setter} = new opt::B::•();
+  opt::testInterface2(new opt3::Mixin2::•());
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart.weak.modular.expect
new file mode 100644
index 0000000..524ceff
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart.weak.modular.expect
@@ -0,0 +1,370 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:17:7: Error: The non-abstract class 'FromSuperAbstract' is missing implementations for these members:
+//  - Interface.field
+//  - Interface.finalField
+//  - Interface.getter
+//  - Interface.method
+//  - Interface.setter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class FromSuperAbstract extends SuperAbstract implements Interface {}
+//       ^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:9:7: Context: 'Interface.field' is defined here.
+//   int field;
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:10:13: Context: 'Interface.finalField' is defined here.
+//   final int finalField;
+//             ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:7:11: Context: 'Interface.getter' is defined here.
+//   int get getter;
+//           ^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:6:8: Context: 'Interface.method' is defined here.
+//   void method();
+//        ^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:8:12: Context: 'Interface.setter=' is defined here.
+//   void set setter(int value);
+//            ^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:35:7: Error: The non-abstract class 'FromMixinAbstract' is missing implementations for these members:
+//  - Interface.field
+//  - Interface.finalField
+//  - Interface.getter
+//  - Interface.method
+//  - Interface.setter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class FromMixinAbstract extends MixinAbstract implements Interface {}
+//       ^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:9:7: Context: 'Interface.field' is defined here.
+//   int field;
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:10:13: Context: 'Interface.finalField' is defined here.
+//   final int finalField;
+//             ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:7:11: Context: 'Interface.getter' is defined here.
+//   int get getter;
+//           ^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:6:8: Context: 'Interface.method' is defined here.
+//   void method();
+//        ^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:8:12: Context: 'Interface.setter=' is defined here.
+//   void set setter(int value);
+//            ^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:54:7: Error: The non-abstract class 'FromInterfaceAbstract' is missing implementations for these members:
+//  - Interface.field
+//  - Interface.finalField
+//  - Interface.getter
+//  - Interface.method
+//  - Interface.setter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class FromInterfaceAbstract implements InterfaceAbstract, Interface {}
+//       ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:9:7: Context: 'Interface.field' is defined here.
+//   int field;
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:10:13: Context: 'Interface.finalField' is defined here.
+//   final int finalField;
+//             ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:7:11: Context: 'Interface.getter' is defined here.
+//   int get getter;
+//           ^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:6:8: Context: 'Interface.method' is defined here.
+//   void method();
+//        ^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:8:12: Context: 'Interface.setter=' is defined here.
+//   void set setter(int value);
+//            ^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:63:7: Error: The non-abstract class 'FromInterfaceConcrete' is missing implementations for these members:
+//  - Interface.field
+//  - Interface.finalField
+//  - Interface.getter
+//  - Interface.method
+//  - Interface.setter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class FromInterfaceConcrete implements InterfaceConcrete, Interface {}
+//       ^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:9:7: Context: 'Interface.field' is defined here.
+//   int field;
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:10:13: Context: 'Interface.finalField' is defined here.
+//   final int finalField;
+//             ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:7:11: Context: 'Interface.getter' is defined here.
+//   int get getter;
+//           ^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:6:8: Context: 'Interface.method' is defined here.
+//   void method();
+//        ^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:8:12: Context: 'Interface.setter=' is defined here.
+//   void set setter(int value);
+//            ^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:65:7: Error: The non-abstract class 'DeclaredAbstract' is missing implementations for these members:
+//  - Interface.field
+//  - Interface.finalField
+//  - Interface.getter
+//  - Interface.method
+//  - Interface.setter=
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class DeclaredAbstract implements Interface {
+//       ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:9:7: Context: 'Interface.field' is defined here.
+//   int field;
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:10:13: Context: 'Interface.finalField' is defined here.
+//   final int finalField;
+//             ^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:7:11: Context: 'Interface.getter' is defined here.
+//   int get getter;
+//           ^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:6:8: Context: 'Interface.method' is defined here.
+//   void method();
+//        ^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:8:12: Context: 'Interface.setter=' is defined here.
+//   void set setter(int value);
+//            ^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:9:7: Error: Field 'field' should be initialized because its type 'int' doesn't allow null.
+//   int field;
+//       ^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/no_such_method.dart:10:13: Error: Final field 'finalField' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int finalField;
+//             ^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  field core::int field = null;
+  final field core::int finalField = null;
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  abstract method method() → void;
+  abstract get getter() → core::int;
+  abstract set setter(core::int value) → void;
+}
+class SuperAbstract extends core::Object {
+  synthetic constructor •() → self::SuperAbstract
+    : super core::Object::•()
+    ;
+  abstract method noSuchMethod(core::Invocation invocation) → dynamic;
+}
+class FromSuperAbstract extends self::SuperAbstract implements self::Interface {
+  synthetic constructor •() → self::FromSuperAbstract
+    : super self::SuperAbstract::•()
+    ;
+}
+class SuperConcrete extends core::Object {
+  synthetic constructor •() → self::SuperConcrete
+    : super core::Object::•()
+    ;
+  @#C1
+  method noSuchMethod(core::Invocation invocation) → dynamic {
+    return null;
+  }
+}
+class FromSuperConcrete extends self::SuperConcrete implements self::Interface {
+  synthetic constructor •() → self::FromSuperConcrete
+    : super self::SuperConcrete::•()
+    ;
+  no-such-method-forwarder get getter() → core::int
+    return this.{self::SuperConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder get field() → core::int
+    return this.{self::SuperConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C6, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder method method() → void
+    return this.{self::SuperConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+  no-such-method-forwarder get finalField() → core::int
+    return this.{self::SuperConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C8, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder set setter(core::int value) → void
+    return this.{self::SuperConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 2, #C3, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+  no-such-method-forwarder set field(core::int value) → void
+    return this.{self::SuperConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C10, 2, #C3, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+}
+class FromSuperConcreteAbstract extends self::SuperConcrete implements self::SuperAbstract, self::Interface {
+  synthetic constructor •() → self::FromSuperConcreteAbstract
+    : super self::SuperConcrete::•()
+    ;
+  no-such-method-forwarder get getter() → core::int
+    return this.{self::SuperConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder get field() → core::int
+    return this.{self::SuperConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C6, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder method method() → void
+    return this.{self::SuperConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+  no-such-method-forwarder get finalField() → core::int
+    return this.{self::SuperConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C8, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder set setter(core::int value) → void
+    return this.{self::SuperConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 2, #C3, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+  no-such-method-forwarder set field(core::int value) → void
+    return this.{self::SuperConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C10, 2, #C3, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+}
+class MixinAbstract extends core::Object {
+  synthetic constructor •() → self::MixinAbstract
+    : super core::Object::•()
+    ;
+  abstract method noSuchMethod(core::Invocation invocation) → dynamic;
+}
+class FromMixinAbstract extends self::MixinAbstract implements self::Interface {
+  synthetic constructor •() → self::FromMixinAbstract
+    : super self::MixinAbstract::•()
+    ;
+}
+class MixinConcrete extends core::Object {
+  synthetic constructor •() → self::MixinConcrete
+    : super core::Object::•()
+    ;
+  @#C1
+  method noSuchMethod(core::Invocation invocation) → dynamic {
+    return null;
+  }
+}
+abstract class _FromMixinConcrete&Object&MixinConcrete = core::Object with self::MixinConcrete /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_FromMixinConcrete&Object&MixinConcrete
+    : super core::Object::•()
+    ;
+  mixin-super-stub method noSuchMethod(core::Invocation invocation) → dynamic
+    return super.{self::MixinConcrete::noSuchMethod}(invocation);
+}
+class FromMixinConcrete extends self::_FromMixinConcrete&Object&MixinConcrete implements self::Interface {
+  synthetic constructor •() → self::FromMixinConcrete
+    : super self::_FromMixinConcrete&Object&MixinConcrete::•()
+    ;
+  no-such-method-forwarder get getter() → core::int
+    return this.{self::_FromMixinConcrete&Object&MixinConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder get field() → core::int
+    return this.{self::_FromMixinConcrete&Object&MixinConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C6, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder method method() → void
+    return this.{self::_FromMixinConcrete&Object&MixinConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+  no-such-method-forwarder get finalField() → core::int
+    return this.{self::_FromMixinConcrete&Object&MixinConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C8, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder set setter(core::int value) → void
+    return this.{self::_FromMixinConcrete&Object&MixinConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 2, #C3, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+  no-such-method-forwarder set field(core::int value) → void
+    return this.{self::_FromMixinConcrete&Object&MixinConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C10, 2, #C3, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+}
+abstract class _FromMixinConcreteAbstract&Object&MixinConcrete = core::Object with self::MixinConcrete /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_FromMixinConcreteAbstract&Object&MixinConcrete
+    : super core::Object::•()
+    ;
+  mixin-super-stub method noSuchMethod(core::Invocation invocation) → dynamic
+    return super.{self::MixinConcrete::noSuchMethod}(invocation);
+}
+abstract class _FromMixinConcreteAbstract&Object&MixinConcrete&MixinAbstract = self::_FromMixinConcreteAbstract&Object&MixinConcrete with self::MixinAbstract /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_FromMixinConcreteAbstract&Object&MixinConcrete&MixinAbstract
+    : super self::_FromMixinConcreteAbstract&Object&MixinConcrete::•()
+    ;
+  abstract mixin-stub method noSuchMethod(core::Invocation invocation) → dynamic; -> self::MixinAbstract::noSuchMethod
+}
+class FromMixinConcreteAbstract extends self::_FromMixinConcreteAbstract&Object&MixinConcrete&MixinAbstract implements self::Interface {
+  synthetic constructor •() → self::FromMixinConcreteAbstract
+    : super self::_FromMixinConcreteAbstract&Object&MixinConcrete&MixinAbstract::•()
+    ;
+  no-such-method-forwarder get getter() → core::int
+    return this.{self::_FromMixinConcreteAbstract&Object&MixinConcrete&MixinAbstract::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder get field() → core::int
+    return this.{self::_FromMixinConcreteAbstract&Object&MixinConcrete&MixinAbstract::noSuchMethod}(new core::_InvocationMirror::_withType(#C6, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder method method() → void
+    return this.{self::_FromMixinConcreteAbstract&Object&MixinConcrete&MixinAbstract::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+  no-such-method-forwarder get finalField() → core::int
+    return this.{self::_FromMixinConcreteAbstract&Object&MixinConcrete&MixinAbstract::noSuchMethod}(new core::_InvocationMirror::_withType(#C8, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder set setter(core::int value) → void
+    return this.{self::_FromMixinConcreteAbstract&Object&MixinConcrete&MixinAbstract::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 2, #C3, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+  no-such-method-forwarder set field(core::int value) → void
+    return this.{self::_FromMixinConcreteAbstract&Object&MixinConcrete&MixinAbstract::noSuchMethod}(new core::_InvocationMirror::_withType(#C10, 2, #C3, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+}
+class InterfaceAbstract extends core::Object {
+  synthetic constructor •() → self::InterfaceAbstract
+    : super core::Object::•()
+    ;
+  abstract method noSuchMethod(core::Invocation invocation) → dynamic;
+}
+class FromInterfaceAbstract extends core::Object implements self::InterfaceAbstract, self::Interface {
+  synthetic constructor •() → self::FromInterfaceAbstract
+    : super core::Object::•()
+    ;
+}
+class InterfaceConcrete extends core::Object {
+  synthetic constructor •() → self::InterfaceConcrete
+    : super core::Object::•()
+    ;
+  @#C1
+  method noSuchMethod(core::Invocation invocation) → dynamic {
+    return null;
+  }
+}
+class FromInterfaceConcrete extends core::Object implements self::InterfaceConcrete, self::Interface {
+  synthetic constructor •() → self::FromInterfaceConcrete
+    : super core::Object::•()
+    ;
+}
+class DeclaredAbstract extends core::Object implements self::Interface {
+  synthetic constructor •() → self::DeclaredAbstract
+    : super core::Object::•()
+    ;
+  abstract method noSuchMethod(core::Invocation invocation) → dynamic;
+}
+class DeclaredConcrete extends core::Object implements self::Interface {
+  synthetic constructor •() → self::DeclaredConcrete
+    : super core::Object::•()
+    ;
+  @#C1
+  method noSuchMethod(core::Invocation invocation) → dynamic {
+    return null;
+  }
+  no-such-method-forwarder get getter() → core::int
+    return this.{self::DeclaredConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder get field() → core::int
+    return this.{self::DeclaredConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C6, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder method method() → void
+    return this.{self::DeclaredConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 0, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+  no-such-method-forwarder get finalField() → core::int
+    return this.{self::DeclaredConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C8, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} core::int;
+  no-such-method-forwarder set setter(core::int value) → void
+    return this.{self::DeclaredConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 2, #C3, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+  no-such-method-forwarder set field(core::int value) → void
+    return this.{self::DeclaredConcrete::noSuchMethod}(new core::_InvocationMirror::_withType(#C10, 2, #C3, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = core::_Override {}
+  #C2 = #getter
+  #C3 = <core::Type*>[]
+  #C4 = <dynamic>[]
+  #C5 = <core::Symbol*, dynamic>{)
+  #C6 = #field
+  #C7 = #method
+  #C8 = #finalField
+  #C9 = #setter=
+  #C10 = #field=
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..2bfc463
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/opt_out.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/override.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/override.dart.weak.modular.expect
new file mode 100644
index 0000000..773c139
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/override.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/override.dart:21:28: Error: The parameter 'i' of the method 'Class.extendedMethod2' has type 'int', which does not match the corresponding type, 'num', in the overridden method, 'Super.extendedMethod2'.
+// Change to a supertype of 'num', or, for a covariant parameter, a subtype.
+//   void extendedMethod2(int i);
+//                            ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/override.dart:10:8: Context: This is the overridden method ('extendedMethod2').
+//   void extendedMethod2(num i) {}
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/override.dart:27:30: Error: The parameter 'n' of the method 'Class.overriddenMethod2' has type 'int', which does not match the corresponding type, 'num', in the overridden method, 'Super.overriddenMethod2'.
+// Change to a supertype of 'num', or, for a covariant parameter, a subtype.
+//   void overriddenMethod2(int n) {}
+//                              ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/override.dart:13:8: Context: This is the overridden method ('overriddenMethod2').
+//   void overriddenMethod2(num n) {}
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/override.dart:16:7: Error: The implementation of 'extendedMethod1' in the non-abstract class 'Class' does not conform to its interface.
+// class Class extends Super {
+//       ^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/override.dart:7:28: Context: The parameter 'i' of the method 'Super.extendedMethod1' has type 'int', which does not match the corresponding type, 'num', in the overridden method, 'Class.extendedMethod1'.
+// Change to a supertype of 'num', or, for a covariant parameter, a subtype.
+//   void extendedMethod1(int i) {}
+//                            ^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/override.dart:18:8: Context: This is the overridden method ('extendedMethod1').
+//   void extendedMethod1(num n);
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  method extendedMethod1(core::int i) → void {}
+  method extendedMethod2(core::num i) → void {}
+  method overriddenMethod1(core::int i) → void {}
+  method overriddenMethod2(core::num n) → void {}
+}
+class Class extends self::Super {
+  synthetic constructor •() → self::Class
+    : super self::Super::•()
+    ;
+  abstract method extendedMethod1(core::num n) → void;
+  abstract method extendedMethod2(core::int i) → void;
+  method overriddenMethod1(core::num n) → void {}
+  method overriddenMethod2(core::int n) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/redirecting_factory.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/redirecting_factory.dart.weak.modular.expect
new file mode 100644
index 0000000..ffdea68
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/redirecting_factory.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  static factory redirect() → self::Class
+    return new self::Class::•();
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::Class::redirect
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart.weak.modular.expect
new file mode 100644
index 0000000..91d4ae2
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart.weak.modular.expect
@@ -0,0 +1,158 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:58:15: Error: Can't declare a member that conflicts with an inherited one.
+//   static void extendedInstanceDeclaredStaticMethod() {}
+//               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:7:8: Context: This is the inherited member.
+//   void extendedInstanceDeclaredStaticMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:67:18: Error: Can't declare a member that conflicts with an inherited one.
+//   static int get extendedInstanceSetterDeclaredStaticGetter => 0;
+//                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:16:12: Context: This is the inherited member.
+//   void set extendedInstanceSetterDeclaredStaticGetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:70:15: Error: Can't declare a member that conflicts with an inherited one.
+//   static void mixedInInstanceDeclaredStaticMethod() {}
+//               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:27:8: Context: This is the inherited member.
+//   void mixedInInstanceDeclaredStaticMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:73:15: Error: Can't declare a member that conflicts with an inherited one.
+//   static void implementedInstanceDeclaredStaticMethod() {}
+//               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:38:8: Context: This is the inherited member.
+//   void implementedInstanceDeclaredStaticMethod() {}
+//        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:82:18: Error: Can't declare a member that conflicts with an inherited one.
+//   static int get implementedInstanceSetterDeclaredStaticGetter => 0;
+//                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:47:12: Context: This is the inherited member.
+//   void set implementedInstanceSetterDeclaredStaticGetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:61:19: Error: Can't declare a member that conflicts with an inherited one.
+//   static void set extendedInstanceDeclaredStaticSetter(int value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:10:12: Context: This is the inherited member.
+//   void set extendedInstanceDeclaredStaticSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:64:19: Error: Can't declare a member that conflicts with an inherited one.
+//   static void set extendedInstanceGetterDeclaredStaticSetter(int value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:13:11: Context: This is the inherited member.
+//   int get extendedInstanceGetterDeclaredStaticSetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:76:19: Error: Can't declare a member that conflicts with an inherited one.
+//   static void set implementedInstanceDeclaredStaticSetter(int value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:41:12: Context: This is the inherited member.
+//   void set implementedInstanceDeclaredStaticSetter(int value) {}
+//            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:79:19: Error: Can't declare a member that conflicts with an inherited one.
+//   static void set implementedInstanceGetterDeclaredStaticSetter(int value) {}
+//                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/nnbd_mixed/hierarchy/static.dart:44:11: Context: This is the inherited member.
+//   int get implementedInstanceGetterDeclaredStaticSetter => 0;
+//           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  static method extendedStaticDeclaredInstanceMethod() → void {}
+  method extendedInstanceDeclaredStaticMethod() → void {}
+  static set extendedStaticDeclaredInstanceSetter(core::int value) → void {}
+  set extendedInstanceDeclaredStaticSetter(core::int value) → void {}
+  static get extendedStaticGetterDeclaredInstanceSetter() → core::int
+    return 0;
+  get extendedInstanceGetterDeclaredStaticSetter() → core::int
+    return 0;
+  static set extendedStaticSetterDeclaredInstanceGetter(core::int value) → void {}
+  set extendedInstanceSetterDeclaredStaticGetter(core::int value) → void {}
+  static method extendedStaticMixedInInstanceMethod() → void {}
+  method extendedInstanceMixedInStaticMethod() → void {}
+  static method extendedStaticImplementedInstanceMethod() → void {}
+  method extendedInstanceImplementedStaticMethod() → void {}
+}
+class Mixin extends core::Object {
+  synthetic constructor •() → self::Mixin
+    : super core::Object::•()
+    ;
+  static method mixedInStaticDeclaredInstanceMethod() → void {}
+  method mixedInInstanceDeclaredStaticMethod() → void {}
+  static method mixedInStaticImplementedInstanceMethod() → void {}
+  method mixedInInstanceImplementedStaticMethod() → void {}
+  method extendedStaticMixedInInstanceMethod() → void {}
+  static method extendedInstanceMixedInStaticMethod() → void {}
+}
+class Interface extends core::Object {
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  static method implementedStaticDeclaredInstanceMethod() → void {}
+  method implementedInstanceDeclaredStaticMethod() → void {}
+  static set implementedStaticDeclaredInstanceSetter(core::int value) → void {}
+  set implementedInstanceDeclaredStaticSetter(core::int value) → void {}
+  static get implementedStaticGetterDeclaredInstanceSetter() → core::int
+    return 0;
+  get implementedInstanceGetterDeclaredStaticSetter() → core::int
+    return 0;
+  static set implementedStaticSetterDeclaredInstanceGetter(core::int value) → void {}
+  set implementedInstanceSetterDeclaredStaticGetter(core::int value) → void {}
+  method extendedStaticImplementedInstanceMethod() → void {}
+  static method extendedInstanceImplementedStaticMethod() → void {}
+  method mixedInStaticImplementedInstanceMethod() → void {}
+  static method mixedInInstanceImplementedStaticMethod() → void {}
+}
+abstract class _Class&Super&Mixin = self::Super with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&Mixin
+    : super self::Super::•()
+    ;
+  mixin-super-stub method mixedInInstanceDeclaredStaticMethod() → void
+    return super.{self::Mixin::mixedInInstanceDeclaredStaticMethod}();
+  mixin-super-stub method mixedInInstanceImplementedStaticMethod() → void
+    return super.{self::Mixin::mixedInInstanceImplementedStaticMethod}();
+  mixin-super-stub method extendedStaticMixedInInstanceMethod() → void
+    return super.{self::Mixin::extendedStaticMixedInInstanceMethod}();
+}
+abstract class Class extends self::_Class&Super&Mixin implements self::Interface {
+  synthetic constructor •() → self::Class
+    : super self::_Class&Super&Mixin::•()
+    ;
+  method extendedStaticDeclaredInstanceMethod() → void {}
+  static method extendedInstanceDeclaredStaticMethod() → void {}
+  set extendedStaticDeclaredInstanceSetter(core::int value) → void {}
+  static set extendedInstanceDeclaredStaticSetter(core::int value) → void {}
+  set extendedStaticGetterDeclaredInstanceSetter(core::int value) → void {}
+  static set extendedInstanceGetterDeclaredStaticSetter(core::int value) → void {}
+  get extendedStaticSetterDeclaredInstanceGetter() → core::int
+    return 0;
+  static get extendedInstanceSetterDeclaredStaticGetter() → core::int
+    return 0;
+  method mixedInStaticDeclaredInstanceMethod() → void {}
+  static method mixedInInstanceDeclaredStaticMethod() → void {}
+  method implementedStaticDeclaredInstanceMethod() → void {}
+  static method implementedInstanceDeclaredStaticMethod() → void {}
+  set implementedStaticDeclaredInstanceSetter(core::int value) → void {}
+  static set implementedInstanceDeclaredStaticSetter(core::int value) → void {}
+  set implementedStaticGetterDeclaredInstanceSetter(core::int value) → void {}
+  static set implementedInstanceGetterDeclaredStaticSetter(core::int value) → void {}
+  get implementedStaticSetterDeclaredInstanceGetter() → core::int
+    return 0;
+  static get implementedInstanceSetterDeclaredStaticGetter() → core::int
+    return 0;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/infer_constraints_from_opt_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/infer_constraints_from_opt_in.dart.weak.modular.expect
new file mode 100644
index 0000000..6cfd88a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/infer_constraints_from_opt_in.dart.weak.modular.expect
@@ -0,0 +1,248 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "infer_constraints_from_opt_in_lib.dart" as inf;
+import "dart:collection" as col;
+
+import "org-dartlang-testcase:///infer_constraints_from_opt_in_lib.dart";
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method baz(inf::B* b) → dynamic {
+    b.{inf::B::foo}(b.{inf::B::bar}<core::List<core::int*>*>(){() →* core::List<core::int*>*}){(core::List<core::int*>*) →* dynamic};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::List<dynamic>* local0 = <dynamic>[];
+  core::List<inf::C<dynamic>*>* local1a = <inf::C<dynamic>*>[inf::field1];
+  core::List<inf::C<dynamic>*>* local1b = <inf::C<dynamic>*>[inf::field2];
+  core::List<inf::C<core::int*>*>* local1c = <inf::C<core::int*>*>[inf::field3];
+  core::List<inf::C<core::int*>*>* local1d = <inf::C<core::int*>*>[inf::field4];
+  core::List<inf::C<core::int*>*>* local1e = <inf::C<core::int*>*>[inf::field5];
+  core::List<inf::C<core::int*>*>* local1f = <inf::C<core::int*>*>[inf::field6];
+  core::List<core::int*>* local1g = <core::int*>[inf::field7];
+  core::List<core::int*>* local1h = <core::int*>[inf::field8];
+  core::List<Null>* local1i = <Null>[null];
+  core::Set<inf::C<dynamic>*>* local2a = block {
+    final core::Set<inf::C<dynamic>*>* #t1 = col::LinkedHashSet::•<inf::C<dynamic>*>();
+    #t1.{core::Set::add}{Invariant}(inf::field1){(inf::C<dynamic>*) →* core::bool*};
+    #t1.{core::Set::add}{Invariant}(null){(inf::C<dynamic>*) →* core::bool*};
+  } =>#t1;
+  core::Set<inf::C<dynamic>*>* local2b = block {
+    final core::Set<inf::C<dynamic>*>* #t2 = col::LinkedHashSet::•<inf::C<dynamic>*>();
+    #t2.{core::Set::add}{Invariant}(inf::field2){(inf::C<dynamic>*) →* core::bool*};
+    #t2.{core::Set::add}{Invariant}(null){(inf::C<dynamic>*) →* core::bool*};
+  } =>#t2;
+  core::Set<inf::C<core::int*>*>* local2c = block {
+    final core::Set<inf::C<core::int*>*>* #t3 = col::LinkedHashSet::•<inf::C<core::int*>*>();
+    #t3.{core::Set::add}{Invariant}(inf::field3){(inf::C<core::int*>*) →* core::bool*};
+    #t3.{core::Set::add}{Invariant}(null){(inf::C<core::int*>*) →* core::bool*};
+  } =>#t3;
+  core::Set<inf::C<core::int*>*>* local2d = block {
+    final core::Set<inf::C<core::int*>*>* #t4 = col::LinkedHashSet::•<inf::C<core::int*>*>();
+    #t4.{core::Set::add}{Invariant}(inf::field4){(inf::C<core::int*>*) →* core::bool*};
+    #t4.{core::Set::add}{Invariant}(null){(inf::C<core::int*>*) →* core::bool*};
+  } =>#t4;
+  core::Set<inf::C<core::int*>*>* local2e = block {
+    final core::Set<inf::C<core::int*>*>* #t5 = col::LinkedHashSet::•<inf::C<core::int*>*>();
+    #t5.{core::Set::add}{Invariant}(inf::field5){(inf::C<core::int*>*) →* core::bool*};
+    #t5.{core::Set::add}{Invariant}(null){(inf::C<core::int*>*) →* core::bool*};
+  } =>#t5;
+  core::Set<inf::C<core::int*>*>* local2f = block {
+    final core::Set<inf::C<core::int*>*>* #t6 = col::LinkedHashSet::•<inf::C<core::int*>*>();
+    #t6.{core::Set::add}{Invariant}(inf::field6){(inf::C<core::int*>*) →* core::bool*};
+    #t6.{core::Set::add}{Invariant}(null){(inf::C<core::int*>*) →* core::bool*};
+  } =>#t6;
+  core::Set<core::int*>* local2g = block {
+    final core::Set<core::int*>* #t7 = col::LinkedHashSet::•<core::int*>();
+    #t7.{core::Set::add}{Invariant}(inf::field7){(core::int*) →* core::bool*};
+    #t7.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t7;
+  core::Set<core::int*>* local2h = block {
+    final core::Set<core::int*>* #t8 = col::LinkedHashSet::•<core::int*>();
+    #t8.{core::Set::add}{Invariant}(inf::field8){(core::int*) →* core::bool*};
+    #t8.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+  } =>#t8;
+  core::Set<inf::C<dynamic>*>* local3a = block {
+    final core::Set<inf::C<dynamic>*>* #t9 = col::LinkedHashSet::•<inf::C<dynamic>*>();
+    #t9.{core::Set::add}{Invariant}(null){(inf::C<dynamic>*) →* core::bool*};
+    #t9.{core::Set::add}{Invariant}(inf::field1){(inf::C<dynamic>*) →* core::bool*};
+  } =>#t9;
+  core::Set<inf::C<dynamic>*>* local3b = block {
+    final core::Set<inf::C<dynamic>*>* #t10 = col::LinkedHashSet::•<inf::C<dynamic>*>();
+    #t10.{core::Set::add}{Invariant}(null){(inf::C<dynamic>*) →* core::bool*};
+    #t10.{core::Set::add}{Invariant}(inf::field2){(inf::C<dynamic>*) →* core::bool*};
+  } =>#t10;
+  core::Set<inf::C<core::int*>*>* local3c = block {
+    final core::Set<inf::C<core::int*>*>* #t11 = col::LinkedHashSet::•<inf::C<core::int*>*>();
+    #t11.{core::Set::add}{Invariant}(null){(inf::C<core::int*>*) →* core::bool*};
+    #t11.{core::Set::add}{Invariant}(inf::field3){(inf::C<core::int*>*) →* core::bool*};
+  } =>#t11;
+  core::Set<inf::C<core::int*>*>* local3d = block {
+    final core::Set<inf::C<core::int*>*>* #t12 = col::LinkedHashSet::•<inf::C<core::int*>*>();
+    #t12.{core::Set::add}{Invariant}(null){(inf::C<core::int*>*) →* core::bool*};
+    #t12.{core::Set::add}{Invariant}(inf::field4){(inf::C<core::int*>*) →* core::bool*};
+  } =>#t12;
+  core::Set<inf::C<core::int*>*>* local3e = block {
+    final core::Set<inf::C<core::int*>*>* #t13 = col::LinkedHashSet::•<inf::C<core::int*>*>();
+    #t13.{core::Set::add}{Invariant}(null){(inf::C<core::int*>*) →* core::bool*};
+    #t13.{core::Set::add}{Invariant}(inf::field5){(inf::C<core::int*>*) →* core::bool*};
+  } =>#t13;
+  core::Set<inf::C<core::int*>*>* local3f = block {
+    final core::Set<inf::C<core::int*>*>* #t14 = col::LinkedHashSet::•<inf::C<core::int*>*>();
+    #t14.{core::Set::add}{Invariant}(null){(inf::C<core::int*>*) →* core::bool*};
+    #t14.{core::Set::add}{Invariant}(inf::field6){(inf::C<core::int*>*) →* core::bool*};
+  } =>#t14;
+  core::Set<core::int*>* local3g = block {
+    final core::Set<core::int*>* #t15 = col::LinkedHashSet::•<core::int*>();
+    #t15.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+    #t15.{core::Set::add}{Invariant}(inf::field7){(core::int*) →* core::bool*};
+  } =>#t15;
+  core::Set<core::int*>* local3h = block {
+    final core::Set<core::int*>* #t16 = col::LinkedHashSet::•<core::int*>();
+    #t16.{core::Set::add}{Invariant}(null){(core::int*) →* core::bool*};
+    #t16.{core::Set::add}{Invariant}(inf::field8){(core::int*) →* core::bool*};
+  } =>#t16;
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/infer_constraints_from_opt_in_lib.dart:11:9: Error: Field 'field5' should be initialized because its type 'C<int?>' doesn't allow null.
+//  - 'C' is from 'pkg/front_end/testcases/nnbd_mixed/infer_constraints_from_opt_in_lib.dart'.
+// C<int?> field5;
+//         ^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/infer_constraints_from_opt_in_lib.dart:13:5: Error: Field 'field7' should be initialized because its type 'int' doesn't allow null.
+// int field7;
+//     ^^^^^^
+//
+import self as inf;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+class C<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → inf::C<inf::C::T%>
+    : super core::Object::•()
+    ;
+}
+abstract class B extends core::Object {
+  synthetic constructor •() → inf::B
+    : super core::Object::•()
+    ;
+  abstract method bar<X extends core::List<core::int?>?>() → inf::B::bar::X%;
+  abstract method foo(core::List<core::int> list) → dynamic;
+}
+static field inf::C<dynamic> field1 = new inf::C::•<dynamic>();
+static field inf::C<dynamic>? field2;
+static field inf::C<core::int> field3 = new inf::C::•<core::int>();
+static field inf::C<core::int>? field4;
+static field inf::C<core::int?> field5;
+static field inf::C<core::int?>? field6;
+static field core::int field7;
+static field core::int? field8;
+static method method() → dynamic {
+  core::List<dynamic> local0 = <dynamic>[];
+  core::List<inf::C<dynamic>> local1a = <inf::C<dynamic>>[inf::field1];
+  core::List<inf::C<dynamic>?> local1b = <inf::C<dynamic>?>[inf::field2];
+  core::List<inf::C<core::int>> local1c = <inf::C<core::int>>[inf::field3];
+  core::List<inf::C<core::int>?> local1d = <inf::C<core::int>?>[inf::field4];
+  core::List<inf::C<core::int?>> local1e = <inf::C<core::int?>>[inf::field5];
+  core::List<inf::C<core::int?>?> local1f = <inf::C<core::int?>?>[inf::field6];
+  core::List<core::int> local1g = <core::int>[inf::field7];
+  core::List<core::int?> local1h = <core::int?>[inf::field8];
+  core::List<Null> local1i = <Null>[null];
+  core::Set<inf::C<dynamic>?> local2a = block {
+    final core::Set<inf::C<dynamic>?> #t17 = col::LinkedHashSet::•<inf::C<dynamic>?>();
+    #t17.{core::Set::add}{Invariant}(inf::field1){(inf::C<dynamic>?) → core::bool};
+    #t17.{core::Set::add}{Invariant}(null){(inf::C<dynamic>?) → core::bool};
+  } =>#t17;
+  core::Set<inf::C<dynamic>?> local2b = block {
+    final core::Set<inf::C<dynamic>?> #t18 = col::LinkedHashSet::•<inf::C<dynamic>?>();
+    #t18.{core::Set::add}{Invariant}(inf::field2){(inf::C<dynamic>?) → core::bool};
+    #t18.{core::Set::add}{Invariant}(null){(inf::C<dynamic>?) → core::bool};
+  } =>#t18;
+  core::Set<inf::C<core::int>?> local2c = block {
+    final core::Set<inf::C<core::int>?> #t19 = col::LinkedHashSet::•<inf::C<core::int>?>();
+    #t19.{core::Set::add}{Invariant}(inf::field3){(inf::C<core::int>?) → core::bool};
+    #t19.{core::Set::add}{Invariant}(null){(inf::C<core::int>?) → core::bool};
+  } =>#t19;
+  core::Set<inf::C<core::int>?> local2d = block {
+    final core::Set<inf::C<core::int>?> #t20 = col::LinkedHashSet::•<inf::C<core::int>?>();
+    #t20.{core::Set::add}{Invariant}(inf::field4){(inf::C<core::int>?) → core::bool};
+    #t20.{core::Set::add}{Invariant}(null){(inf::C<core::int>?) → core::bool};
+  } =>#t20;
+  core::Set<inf::C<core::int?>?> local2e = block {
+    final core::Set<inf::C<core::int?>?> #t21 = col::LinkedHashSet::•<inf::C<core::int?>?>();
+    #t21.{core::Set::add}{Invariant}(inf::field5){(inf::C<core::int?>?) → core::bool};
+    #t21.{core::Set::add}{Invariant}(null){(inf::C<core::int?>?) → core::bool};
+  } =>#t21;
+  core::Set<inf::C<core::int?>?> local2f = block {
+    final core::Set<inf::C<core::int?>?> #t22 = col::LinkedHashSet::•<inf::C<core::int?>?>();
+    #t22.{core::Set::add}{Invariant}(inf::field6){(inf::C<core::int?>?) → core::bool};
+    #t22.{core::Set::add}{Invariant}(null){(inf::C<core::int?>?) → core::bool};
+  } =>#t22;
+  core::Set<core::int?> local2g = block {
+    final core::Set<core::int?> #t23 = col::LinkedHashSet::•<core::int?>();
+    #t23.{core::Set::add}{Invariant}(inf::field7){(core::int?) → core::bool};
+    #t23.{core::Set::add}{Invariant}(null){(core::int?) → core::bool};
+  } =>#t23;
+  core::Set<core::int?> local2h = block {
+    final core::Set<core::int?> #t24 = col::LinkedHashSet::•<core::int?>();
+    #t24.{core::Set::add}{Invariant}(inf::field8){(core::int?) → core::bool};
+    #t24.{core::Set::add}{Invariant}(null){(core::int?) → core::bool};
+  } =>#t24;
+  core::Set<inf::C<dynamic>?> local3a = block {
+    final core::Set<inf::C<dynamic>?> #t25 = col::LinkedHashSet::•<inf::C<dynamic>?>();
+    #t25.{core::Set::add}{Invariant}(null){(inf::C<dynamic>?) → core::bool};
+    #t25.{core::Set::add}{Invariant}(inf::field1){(inf::C<dynamic>?) → core::bool};
+  } =>#t25;
+  core::Set<inf::C<dynamic>?> local3b = block {
+    final core::Set<inf::C<dynamic>?> #t26 = col::LinkedHashSet::•<inf::C<dynamic>?>();
+    #t26.{core::Set::add}{Invariant}(null){(inf::C<dynamic>?) → core::bool};
+    #t26.{core::Set::add}{Invariant}(inf::field2){(inf::C<dynamic>?) → core::bool};
+  } =>#t26;
+  core::Set<inf::C<core::int>?> local3c = block {
+    final core::Set<inf::C<core::int>?> #t27 = col::LinkedHashSet::•<inf::C<core::int>?>();
+    #t27.{core::Set::add}{Invariant}(null){(inf::C<core::int>?) → core::bool};
+    #t27.{core::Set::add}{Invariant}(inf::field3){(inf::C<core::int>?) → core::bool};
+  } =>#t27;
+  core::Set<inf::C<core::int>?> local3d = block {
+    final core::Set<inf::C<core::int>?> #t28 = col::LinkedHashSet::•<inf::C<core::int>?>();
+    #t28.{core::Set::add}{Invariant}(null){(inf::C<core::int>?) → core::bool};
+    #t28.{core::Set::add}{Invariant}(inf::field4){(inf::C<core::int>?) → core::bool};
+  } =>#t28;
+  core::Set<inf::C<core::int?>?> local3e = block {
+    final core::Set<inf::C<core::int?>?> #t29 = col::LinkedHashSet::•<inf::C<core::int?>?>();
+    #t29.{core::Set::add}{Invariant}(null){(inf::C<core::int?>?) → core::bool};
+    #t29.{core::Set::add}{Invariant}(inf::field5){(inf::C<core::int?>?) → core::bool};
+  } =>#t29;
+  core::Set<inf::C<core::int?>?> local3f = block {
+    final core::Set<inf::C<core::int?>?> #t30 = col::LinkedHashSet::•<inf::C<core::int?>?>();
+    #t30.{core::Set::add}{Invariant}(null){(inf::C<core::int?>?) → core::bool};
+    #t30.{core::Set::add}{Invariant}(inf::field6){(inf::C<core::int?>?) → core::bool};
+  } =>#t30;
+  core::Set<core::int?> local3g = block {
+    final core::Set<core::int?> #t31 = col::LinkedHashSet::•<core::int?>();
+    #t31.{core::Set::add}{Invariant}(null){(core::int?) → core::bool};
+    #t31.{core::Set::add}{Invariant}(inf::field7){(core::int?) → core::bool};
+  } =>#t31;
+  core::Set<core::int?> local3h = block {
+    final core::Set<core::int?> #t32 = col::LinkedHashSet::•<core::int?>();
+    #t32.{core::Set::add}{Invariant}(null){(core::int?) → core::bool};
+    #t32.{core::Set::add}{Invariant}(inf::field8){(core::int?) → core::bool};
+  } =>#t32;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/infer_from_opt_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/infer_from_opt_in.dart.weak.modular.expect
new file mode 100644
index 0000000..ff3f272
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/infer_from_opt_in.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "infer_from_opt_in_lib.dart" as inf;
+
+import "org-dartlang-testcase:///infer_from_opt_in_lib.dart";
+
+static method reify<T extends core::Object? = dynamic>(self::reify::T% arg) → dynamic
+  return self::reify::T%;
+static method main() → dynamic {
+  inf::Foo x = new inf::Foo::•();
+  inf::Foo y = new inf::Foo::•();
+  () → inf::Foo z = () → inf::Foo => inf::createFoo();
+  inf::callback((inf::Foo? x) → inf::Foo? => x);
+  core::print(self::reify<inf::Foo>(x));
+  core::print(self::reify<inf::Foo>(y));
+  core::print(self::reify<() → inf::Foo>(z));
+}
+
+library /*isNonNullableByDefault*/;
+import self as inf;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → inf::Foo
+    : super core::Object::•()
+    ;
+}
+static method createFoo() → inf::Foo
+  return new inf::Foo::•();
+static method callback((inf::Foo?) → inf::Foo? f) → void {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/infer_from_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/infer_from_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..2a1443f
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/infer_from_opt_out.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "infer_from_opt_out_lib.dart" as inf;
+
+import "org-dartlang-testcase:///infer_from_opt_out_lib.dart";
+
+static method reify<T extends core::Object? = dynamic>(self::reify::T% arg) → dynamic
+  return self::reify::T%;
+static method main() → dynamic {
+  inf::Foo x = new inf::Foo::•();
+  inf::Foo y = new inf::Foo::•();
+  () → inf::Foo z = () → inf::Foo => inf::createFoo();
+  inf::callback((inf::Foo x) → inf::Foo => x);
+  core::print(self::reify<inf::Foo>(x));
+  core::print(self::reify<inf::Foo>(y));
+  core::print(self::reify<() → inf::Foo>(z));
+}
+
+library;
+import self as inf;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → inf::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method createFoo() → inf::Foo*
+  return new inf::Foo::•();
+static method callback((inf::Foo*) →* inf::Foo* f) → void {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/infer_in_legacy_from_opted_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/infer_in_legacy_from_opted_in.dart.weak.modular.expect
new file mode 100644
index 0000000..2ae2d77
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/infer_in_legacy_from_opted_in.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "infer_in_legacy_from_opted_in_lib.dart" as inf;
+
+import "org-dartlang-testcase:///infer_in_legacy_from_opted_in_lib.dart";
+
+static method bar(core::int* x) → dynamic {
+  inf::baz(inf::foo<core::int*>(x, inf::y));
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as inf;
+import "dart:core" as core;
+
+static field core::int y = 42;
+static method foo<T extends core::num>(inf::foo::T t1, inf::foo::T t2) → inf::foo::T
+  return t1;
+static method baz(core::int? v) → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/infer_object_from_dynamic/main.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/infer_object_from_dynamic/main.dart.weak.modular.expect
new file mode 100644
index 0000000..216a6b7
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/infer_object_from_dynamic/main.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "opt_out_lib.dart" as opt;
+
+import "org-dartlang-testcase:///opt_out_lib.dart";
+
+static method foo(dynamic d, void v, core::Object? onull, core::Object o, core::String? snull, core::String s) → dynamic {
+  opt::f<dynamic>(d);
+  opt::f<void>(v);
+  opt::f<core::Object?>(onull);
+  opt::f<core::Object>(o);
+  opt::f<core::String?>(snull);
+  opt::f<core::String>(s);
+}
+static method main() → dynamic {}
+
+library;
+import self as opt;
+import "dart:core" as core;
+
+static method f<T extends core::Object* = dynamic>(opt::f::T* a) → opt::f::T*
+  return a;
diff --git a/pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_in.dart.weak.modular.expect
new file mode 100644
index 0000000..c254d31
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_in.dart.weak.modular.expect
@@ -0,0 +1,242 @@
+//
+// Problems in component:
+//
+// pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_in.dart:27:7: Error: 'LegacyClass5' can't implement both 'GenericInterface<dynamic>' and 'GenericInterface<Object>'
+//  - 'GenericInterface' is from 'pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_in_lib.dart'.
+//  - 'Object' is from 'dart:core'.
+// class LegacyClass5 extends Class5 implements GenericInterface<Object> {}
+//       ^
+//
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_in.dart:21:52: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+// class LegacyClass4c implements GenericInterface<num?> {}
+//                                                    ^
+// pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_in.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.5
+// ^^^^^^^^^^^^
+//
+import self as self;
+import "inheritance_from_opt_in_lib.dart" as inh;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///inheritance_from_opt_in_lib.dart";
+
+class LegacyClass1 extends inh::Class1 {
+  synthetic constructor •() → self::LegacyClass1*
+    : super inh::Class1::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass2<T extends core::Object* = dynamic> extends inh::Class2<self::LegacyClass2::T*> {
+  synthetic constructor •() → self::LegacyClass2<self::LegacyClass2::T*>*
+    : super inh::Class2::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass3a<T extends core::Object* = dynamic> extends inh::Class3<self::LegacyClass3a::T*> {
+  synthetic constructor •() → self::LegacyClass3a<self::LegacyClass3a::T*>*
+    : super inh::Class3::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass3b<T extends core::Object* = dynamic> extends inh::Class3<self::LegacyClass3b::T*> implements inh::GenericInterface<self::LegacyClass3b::T*> {
+  synthetic constructor •() → self::LegacyClass3b<self::LegacyClass3b::T*>*
+    : super inh::Class3::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass4a extends inh::Class4a {
+  synthetic constructor •() → self::LegacyClass4a*
+    : super inh::Class4a::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass4b extends core::Object implements inh::GenericInterface<core::num*> {
+  synthetic constructor •() → self::LegacyClass4b*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass4c extends core::Object implements inh::GenericInterface<core::num*> {
+  synthetic constructor •() → self::LegacyClass4c*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass4d extends inh::Class4a implements inh::GenericInterface<core::num*> {
+  synthetic constructor •() → self::LegacyClass4d*
+    : super inh::Class4a::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass4e extends core::Object implements inh::Class4a, inh::Class4b {
+  synthetic constructor •() → self::LegacyClass4e*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass5 extends inh::Class5 implements inh::GenericInterface<core::Object*> {
+  synthetic constructor •() → self::LegacyClass5*
+    : super inh::Class5::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass6a<T extends core::Object* = dynamic> extends inh::Class3<self::LegacyClass6a::T*> implements inh::GenericSubInterface<self::LegacyClass6a::T*> {
+  synthetic constructor •() → self::LegacyClass6a<self::LegacyClass6a::T*>*
+    : super inh::Class3::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass6b<T extends core::Object* = dynamic> extends self::LegacyClass3a<self::LegacyClass6b::T*> implements inh::GenericSubInterface<self::LegacyClass6b::T*> {
+  synthetic constructor •() → self::LegacyClass6b<self::LegacyClass6b::T*>*
+    : super self::LegacyClass3a::•()
+    ;
+}
+
+library /*isNonNullableByDefault*/;
+import self as inh;
+import "dart:core" as core;
+
+abstract class GenericInterface<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → inh::GenericInterface<inh::GenericInterface::T%>
+    : super core::Object::•()
+    ;
+}
+abstract class GenericSubInterface<T extends core::Object? = dynamic> extends inh::GenericInterface<inh::GenericSubInterface::T%> {
+  synthetic constructor •() → inh::GenericSubInterface<inh::GenericSubInterface::T%>
+    : super inh::GenericInterface::•()
+    ;
+}
+class Class1 extends core::Object {
+  synthetic constructor •() → inh::Class1
+    : super core::Object::•()
+    ;
+}
+class Class2<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → inh::Class2<inh::Class2::T%>
+    : super core::Object::•()
+    ;
+}
+class Class3<T extends core::Object? = dynamic> extends core::Object implements inh::GenericInterface<inh::Class3::T%> {
+  synthetic constructor •() → inh::Class3<inh::Class3::T%>
+    : super core::Object::•()
+    ;
+}
+class Class4a extends core::Object implements inh::GenericInterface<core::num> {
+  synthetic constructor •() → inh::Class4a
+    : super core::Object::•()
+    ;
+}
+class Class4b extends core::Object implements inh::GenericInterface<core::num?> {
+  synthetic constructor •() → inh::Class4b
+    : super core::Object::•()
+    ;
+}
+class Class5 extends core::Object implements inh::GenericInterface<dynamic> {
+  synthetic constructor •() → inh::Class5
+    : super core::Object::•()
+    ;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..b2fa606
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_out.dart.weak.modular.expect
@@ -0,0 +1,195 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "inheritance_from_opt_out_lib.dart" as inh;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///inheritance_from_opt_out_lib.dart";
+
+class Class1 extends inh::LegacyClass1 {
+  synthetic constructor •() → self::Class1
+    : super inh::LegacyClass1::•()
+    ;
+}
+class Class2<T extends core::Object? = dynamic> extends inh::LegacyClass2<self::Class2::T%> {
+  synthetic constructor •() → self::Class2<self::Class2::T%>
+    : super inh::LegacyClass2::•()
+    ;
+}
+class Class3a<T extends core::Object? = dynamic> extends inh::LegacyClass3<self::Class3a::T%> {
+  synthetic constructor •() → self::Class3a<self::Class3a::T%>
+    : super inh::LegacyClass3::•()
+    ;
+}
+class Class3b<T extends core::Object? = dynamic> extends inh::LegacyClass3<self::Class3b::T%> implements inh::GenericInterface<self::Class3b::T%> {
+  synthetic constructor •() → self::Class3b<self::Class3b::T%>
+    : super inh::LegacyClass3::•()
+    ;
+}
+class Class4a extends inh::LegacyClass4 {
+  synthetic constructor •() → self::Class4a
+    : super inh::LegacyClass4::•()
+    ;
+}
+class Class4b extends core::Object implements inh::GenericInterface<core::num> {
+  synthetic constructor •() → self::Class4b
+    : super core::Object::•()
+    ;
+  abstract member-signature operator /*isLegacy*/ ==(dynamic other) → core::bool*; -> core::Object::==
+}
+class Class4c extends core::Object implements inh::GenericInterface<core::num?> {
+  synthetic constructor •() → self::Class4c
+    : super core::Object::•()
+    ;
+  abstract member-signature operator /*isLegacy*/ ==(dynamic other) → core::bool*; -> core::Object::==
+}
+class Class4d extends inh::LegacyClass4 implements inh::GenericInterface<core::num> {
+  synthetic constructor •() → self::Class4d
+    : super inh::LegacyClass4::•()
+    ;
+}
+static method main() → dynamic {}
+
+library;
+import self as inh;
+import "dart:core" as core;
+
+abstract class GenericInterface<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → inh::GenericInterface<inh::GenericInterface::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class GenericSubInterface<T extends core::Object* = dynamic> extends core::Object implements inh::GenericInterface<inh::GenericSubInterface::T*> {
+  synthetic constructor •() → inh::GenericSubInterface<inh::GenericSubInterface::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass1 extends core::Object {
+  synthetic constructor •() → inh::LegacyClass1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass2<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → inh::LegacyClass2<inh::LegacyClass2::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass3<T extends core::Object* = dynamic> extends core::Object implements inh::GenericInterface<inh::LegacyClass3::T*> {
+  synthetic constructor •() → inh::LegacyClass3<inh::LegacyClass3::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass4 extends core::Object implements inh::GenericInterface<core::num*> {
+  synthetic constructor •() → inh::LegacyClass4*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass5<T extends core::Object* = dynamic> extends inh::LegacyClass3<inh::LegacyClass5::T*> implements inh::GenericInterface<inh::LegacyClass5::T*> {
+  synthetic constructor •() → inh::LegacyClass5<inh::LegacyClass5::T*>*
+    : super inh::LegacyClass3::•()
+    ;
+}
+abstract class _LegacyClass6&Object&LegacyClass3<T extends core::Object* = dynamic> = core::Object with inh::LegacyClass3<inh::_LegacyClass6&Object&LegacyClass3::T*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → inh::_LegacyClass6&Object&LegacyClass3<inh::_LegacyClass6&Object&LegacyClass3::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass6<T extends core::Object* = dynamic> extends inh::_LegacyClass6&Object&LegacyClass3<inh::LegacyClass6::T*> implements inh::GenericInterface<inh::LegacyClass6::T*> {
+  synthetic constructor •() → inh::LegacyClass6<inh::LegacyClass6::T*>*
+    : super inh::_LegacyClass6&Object&LegacyClass3::•()
+    ;
+}
+class LegacyClass7<T extends core::Object* = dynamic> extends inh::LegacyClass3<inh::LegacyClass7::T*> implements inh::GenericSubInterface<inh::LegacyClass7::T*> {
+  synthetic constructor •() → inh::LegacyClass7<inh::LegacyClass7::T*>*
+    : super inh::LegacyClass3::•()
+    ;
+}
+abstract class _LegacyClass8&Object&LegacyClass3<T extends core::Object* = dynamic> = core::Object with inh::LegacyClass3<inh::_LegacyClass8&Object&LegacyClass3::T*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → inh::_LegacyClass8&Object&LegacyClass3<inh::_LegacyClass8&Object&LegacyClass3::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class LegacyClass8<T extends core::Object* = dynamic> extends inh::_LegacyClass8&Object&LegacyClass3<inh::LegacyClass8::T*> implements inh::GenericSubInterface<inh::LegacyClass8::T*> {
+  synthetic constructor •() → inh::LegacyClass8<inh::LegacyClass8::T*>*
+    : super inh::_LegacyClass8&Object&LegacyClass3::•()
+    ;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue39666.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue39666.dart.weak.modular.expect
new file mode 100644
index 0000000..779a4e3
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue39666.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+import "org-dartlang-testcase:///issue39666_lib.dart";
+
+class A<X extends FutureOr<core::List<dynamic>>> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X>
+    : super core::Object::•()
+    ;
+}
+static method main() → void {}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+import "dart:async";
+
+class A<X extends FutureOr<core::List<dynamic>*>*> extends core::Object {
+  synthetic constructor •() → self2::A<self2::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue40512/issue40512.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue40512/issue40512.dart.weak.modular.expect
new file mode 100644
index 0000000..3ea0d63
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue40512/issue40512.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "issue40512_lib.dart" as baz2;
+
+import "org-dartlang-testcase:///issue40512_lib.dart";
+
+abstract class _C&Object&A = core::Object with baz2::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  mixin-super-stub method toString({core::String* s = #C1}) → core::String*
+    return super.{baz2::A::toString}(s: s);
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&Object&A&B = self::_C&Object&A with baz2::B /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A&B*
+    : super self::_C&Object&A::•()
+    ;
+}
+class C extends self::_C&Object&A&B {
+  synthetic constructor •() → self::C*
+    : super self::_C&Object&A&B::•()
+    ;
+}
+static method main() → void {
+  core::print(new baz2::B::•());
+  core::print(new self::C::•());
+}
+
+constants  {
+  #C1 = "hello"
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue40512/issue40512.no_link.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue40512/issue40512.no_link.dart.weak.modular.expect
new file mode 100644
index 0000000..5ce29b0
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue40512/issue40512.no_link.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "issue40512_lib.dart" as baz2;
+
+import "org-dartlang-testcase:///issue40512_lib.dart";
+
+abstract class _C&Object&A = core::Object with baz2::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method toString({core::String* s = #C1}) → core::String*
+    return super.{baz2::A::toString}(s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&Object&A&B = self::_C&Object&A with baz2::B /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A&B*
+    : super self::_C&Object&A::•()
+    ;
+}
+class C extends self::_C&Object&A&B {
+  synthetic constructor •() → self::C*
+    : super self::_C&Object&A&B::•()
+    ;
+}
+static method main() → void {
+  core::print(new baz2::B::•());
+  core::print(new self::C::•());
+}
+
+library baz2;
+import self as baz2;
+import "dart:core" as core;
+
+abstract class A extends core::Object /*isMixinDeclaration*/  {
+  method toString({core::String* s = #C1}) → core::String*
+    return s;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → baz2::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+constants  {
+  #C1 = "hello"
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41180.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue41180.dart.weak.modular.expect
new file mode 100644
index 0000000..7e095fc
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41180.dart.weak.modular.expect
@@ -0,0 +1,77 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "issue41180_lib.dart" as iss;
+
+import "org-dartlang-testcase:///issue41180_lib.dart";
+
+class D<Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::D<self::D::Y*>*
+    : super core::Object::•()
+    ;
+  method method() → iss::C<self::D::Y*>*
+    return new iss::C::•<self::D::Y*>(() → Null => null);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {
+  iss::foo(() → Null => null);
+  iss::bar = () → iss::Map<core::String*, core::String*>* => null;
+  new self::D::•<core::int*>().{self::D::method}(){() →* iss::C<core::int*>*};
+  self::findKey(new iss::Map::•<core::String*, core::String*>("foo", "bar"), "bar");
+}
+static method findKey(iss::Map<core::String*, dynamic>* m, dynamic search) → void {
+  core::print(let final core::MapEntry<core::String*, dynamic>* #t1 = m.{iss::Map::entries}{iss::Iterable<core::MapEntry<core::String*, dynamic>*>*}.{iss::Iterable::singleWhere}((core::MapEntry<core::String*, dynamic>* entry) → core::bool* => entry.{core::MapEntry::value}{dynamic} =={core::Object::==}{(core::Object*) →* core::bool*} search, orElse: () → Null => null){((core::MapEntry<core::String*, dynamic>*) →* core::bool*, {orElse: () →* core::MapEntry<core::String*, dynamic>*}) →* core::MapEntry<core::String*, dynamic>*} in #t1 == null ?{core::String*} null : #t1.{core::MapEntry::key}{core::String*});
+}
+
+library /*isNonNullableByDefault*/;
+import self as iss;
+import "dart:core" as core;
+
+class C<X extends core::Object? = dynamic> extends core::Object {
+  constructor •(() → iss::Map<core::String, core::String> f) → iss::C<iss::C::X%>
+    : super core::Object::•() {
+    core::print(f.{core::Object::runtimeType}{core::Type});
+  }
+}
+class Map<K extends core::Object? = dynamic, V extends core::Object? = dynamic> extends core::Object {
+  final field iss::Map::K% key;
+  final field iss::Map::V% value;
+  constructor •(iss::Map::K% key, iss::Map::V% value) → iss::Map<iss::Map::K%, iss::Map::V%>
+    : iss::Map::key = key, iss::Map::value = value, super core::Object::•()
+    ;
+  get entries() → iss::Iterable<core::MapEntry<iss::Map::K%, iss::Map::V%>>
+    return new iss::Iterable::•<core::MapEntry<iss::Map::K%, iss::Map::V%>>(new core::MapEntry::_<iss::Map::K%, iss::Map::V%>(this.{iss::Map::key}{iss::Map::K%}, this.{iss::Map::value}{iss::Map::V%}));
+}
+class Iterable<E extends core::Object? = dynamic> extends core::Object {
+  final field iss::Iterable::E% element;
+  constructor •(iss::Iterable::E% element) → iss::Iterable<iss::Iterable::E%>
+    : iss::Iterable::element = element, super core::Object::•()
+    ;
+  method singleWhere((iss::Iterable::E%) → core::bool test, {covariant-by-class () →? iss::Iterable::E% orElse = #C1}) → iss::Iterable::E% {
+    if(test(this.{iss::Iterable::element}{iss::Iterable::E%}){(iss::Iterable::E%) → core::bool}) {
+      return this.{iss::Iterable::element}{iss::Iterable::E%};
+    }
+    if(!(orElse == null))
+      return orElse{() → iss::Iterable::E%}(){() → iss::Iterable::E%};
+    throw "error";
+  }
+}
+static method foo(() → iss::Map<core::String, core::String> f) → void {
+  core::print(f.{core::Object::runtimeType}{core::Type});
+}
+static set bar(() → iss::Map<core::String, core::String> f) → void {
+  core::print(f.{core::Object::runtimeType}{core::Type});
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41210a/issue41210.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue41210a/issue41210.dart.weak.modular.expect
new file mode 100644
index 0000000..27a93fe
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41210a/issue41210.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "issue41210_lib1.dart" as iss;
+
+import "org-dartlang-testcase:///issue41210_lib1.dart";
+
+abstract class _C&Object&A = core::Object with iss::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  mixin-super-stub method method({core::String* s = #C1}) → core::String*
+    return super.{iss::A::method}(s: s);
+}
+abstract class _C&Object&A&B = self::_C&Object&A with iss::B /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A&B*
+    : super self::_C&Object&A::•()
+    ;
+}
+class C extends self::_C&Object&A&B {
+  synthetic constructor •() → self::C*
+    : super self::_C&Object&A&B::•()
+    ;
+}
+static method main() → dynamic {
+  core::print(new self::C::•().{self::_C&Object&A::method}(){({s: core::String*}) →* core::String*});
+}
+
+constants  {
+  #C1 = "hello"
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41210a/issue41210.no_link.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue41210a/issue41210.no_link.dart.weak.modular.expect
new file mode 100644
index 0000000..7ab45bf
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41210a/issue41210.no_link.dart.weak.modular.expect
@@ -0,0 +1,91 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "issue41210_lib1.dart" as iss;
+
+import "org-dartlang-testcase:///issue41210_lib1.dart";
+
+abstract class _C&Object&A = core::Object with iss::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method({core::String* s = #C1}) → core::String*
+    return super.{iss::A::method}(s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&Object&A&B = self::_C&Object&A with iss::B /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A&B*
+    : super self::_C&Object&A::•()
+    ;
+}
+class C extends self::_C&Object&A&B {
+  synthetic constructor •() → self::C*
+    : super self::_C&Object&A&B::•()
+    ;
+}
+static method main() → dynamic {
+  core::print(new self::C::•().{self::_C&Object&A::method}(){({s: core::String*}) →* core::String*});
+}
+
+library;
+import self as iss;
+import "dart:core" as core;
+import "issue41210_lib2.dart" as iss2;
+
+import "org-dartlang-testcase:///issue41210_lib2.dart";
+
+abstract class A extends core::Object implements iss2::Interface /*isMixinDeclaration*/  {
+  method method({core::String* s = #C1}) → core::String*
+    return s;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object implements iss2::Interface {
+  synthetic constructor •() → iss::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature method method() → core::String*; -> iss2::Interface::method
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {}
+
+library /*isNonNullableByDefault*/;
+import self as iss2;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  synthetic constructor •() → iss2::Interface
+    : super core::Object::•()
+    ;
+  abstract method method() → core::String;
+}
+
+constants  {
+  #C1 = "hello"
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41210b.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue41210b.dart.weak.modular.expect
new file mode 100644
index 0000000..2f375fb
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41210b.dart.weak.modular.expect
@@ -0,0 +1,91 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "issue41210b_lib1.dart" as iss;
+
+import "org-dartlang-testcase:///issue41210b_lib1.dart";
+
+abstract class _C&Object&A = core::Object with iss::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method({core::String* s = #C1}) → core::String*
+    return super.{iss::A::method}(s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&Object&A&B = self::_C&Object&A with iss::B /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&A&B*
+    : super self::_C&Object&A::•()
+    ;
+}
+class C extends self::_C&Object&A&B {
+  synthetic constructor •() → self::C*
+    : super self::_C&Object&A&B::•()
+    ;
+}
+static method main() → dynamic {
+  core::print(new self::C::•().{self::_C&Object&A::method}(){({s: core::String*}) →* core::String*});
+}
+
+library;
+import self as iss;
+import "dart:core" as core;
+import "issue41210b_lib2.dart" as iss2;
+
+import "org-dartlang-testcase:///issue41210b_lib2.dart";
+
+abstract class A extends core::Object implements iss2::Interface /*isMixinDeclaration*/  {
+  method method({core::String* s = #C1}) → core::String*
+    return s;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object implements iss2::Interface {
+  synthetic constructor •() → iss::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature method method() → core::String*; -> iss2::Interface::method
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {}
+
+library /*isNonNullableByDefault*/;
+import self as iss2;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  synthetic constructor •() → iss2::Interface
+    : super core::Object::•()
+    ;
+  abstract method method() → core::String;
+}
+
+constants  {
+  #C1 = "hello"
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41435.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue41435.dart.weak.modular.expect
new file mode 100644
index 0000000..5d1e11f
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41435.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library;
+import self as self;
+import "issue41435_lib.dart" as iss;
+
+import "org-dartlang-testcase:///issue41435_lib.dart";
+
+static method main() → void {
+  Null nil;
+  iss::x = null;
+  iss::x = nil;
+  iss::takesNever(null);
+  iss::takesNever(nil);
+  iss::takesTakesNull(#C1);
+  iss::f = (Null x) → Null {};
+}
+
+library /*isNonNullableByDefault*/;
+import self as iss;
+import "dart:core" as core;
+
+static field Never x = throw "Unreachable";
+static field (Null) → void f = (core::Object? n) → void {};
+static method takesNever(Never x) → void {}
+static method takesTakesNull((Null) → void f) → void {}
+
+constants  {
+  #C1 = static-tearoff iss::takesNever
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41496.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue41496.dart.weak.modular.expect
new file mode 100644
index 0000000..e3dae37
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41496.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41496.dart:7:11: Error: Field 'f1' should be initialized because its type 'void Function()' doesn't allow null.
+// LegacyFoo f1;
+//           ^^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41496.dart:10:20: Error: Field 'f2' should be initialized because its type 'void Function()' doesn't allow null.
+//   static LegacyFoo f2;
+//                    ^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue41496_lib.dart";
+
+class C extends core::Object {
+  static field () → void f2 = null;
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+static field () → void f1;
+static method main() → dynamic {
+  new self::C::•();
+}
+
+library opted_out_lib;
+import self as self2;
+
+typedef LegacyFoo = () →* void;
+static method test(() →* void f) → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41496b.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue41496b.dart.weak.modular.expect
new file mode 100644
index 0000000..0144b18
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41496b.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library opted_out_lib;
+import self as self;
+import "issue41496b_lib.dart" as iss;
+
+import "org-dartlang-testcase:///issue41496b_lib.dart" as opt_in;
+
+typedef LegacyFoo = () →* void;
+static method test(() →* void f) → dynamic {}
+static method main() → dynamic {
+  iss::main();
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41496b_lib.dart:7:11: Error: Field 'f1' should be initialized because its type 'void Function()' doesn't allow null.
+// LegacyFoo f1;
+//           ^^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41496b_lib.dart:10:20: Error: Field 'f2' should be initialized because its type 'void Function()' doesn't allow null.
+//   static LegacyFoo f2;
+//                    ^^
+//
+import self as iss;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue41496b.dart";
+
+class C extends core::Object {
+  static field () → void f2 = null;
+  synthetic constructor •() → iss::C
+    : super core::Object::•()
+    ;
+}
+static field () → void f1;
+static method main() → dynamic {
+  new iss::C::•();
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41498.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue41498.dart.weak.modular.expect
new file mode 100644
index 0000000..ebb0722
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41498.dart.weak.modular.expect
@@ -0,0 +1,96 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41498.dart:11:5: Error: Non-nullable variable 'f' must be assigned before it can be used.
+//     f.toString(); // error
+//     ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41498.dart:17:5: Error: Non-nullable variable 'f' must be assigned before it can be used.
+//     f.toString(); // error
+//     ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41498.dart:24:3: Error: Non-nullable variable 'f' must be assigned before it can be used.
+//   f.toString(); // error
+//   ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41498.dart:29:5: Error: Non-nullable variable 'f' must be assigned before it can be used.
+//     f.toString(); // error
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue41498_lib.dart";
+
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  static method test() → void {
+    () → void f;
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41498.dart:11:5: Error: Non-nullable variable 'f' must be assigned before it can be used.
+    f.toString(); // error
+    ^" in f.{core::Object::toString}(){() → core::String};
+  }
+  method test2() → void {
+    () → void f;
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41498.dart:17:5: Error: Non-nullable variable 'f' must be assigned before it can be used.
+    f.toString(); // error
+    ^" in f.{core::Object::toString}(){() → core::String};
+  }
+}
+static method test() → dynamic {
+  () → void f;
+  invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41498.dart:24:3: Error: Non-nullable variable 'f' must be assigned before it can be used.
+  f.toString(); // error
+  ^" in f.{core::Object::toString}(){() → core::String};
+  core::Function foo = () → Null {
+    () → void f;
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41498.dart:29:5: Error: Non-nullable variable 'f' must be assigned before it can be used.
+    f.toString(); // error
+    ^" in f.{core::Object::toString}(){() → core::String};
+  };
+  self::C::test();
+  new self::C::•().{self::C::test2}(){() → void};
+}
+static method main() → dynamic {}
+
+library opted_out_lib;
+import self as self2;
+import "dart:core" as core;
+
+typedef LegacyFoo = () →* void;
+class C extends core::Object {
+  synthetic constructor •() → self2::C*
+    : super core::Object::•()
+    ;
+  static method test() → void {
+    () →* void f;
+    f.{core::Object::toString}(){() →* core::String*};
+  }
+  method test2() → void {
+    () →* void f;
+    f.{core::Object::toString}(){() →* core::String*};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  () →* void f;
+  f.{core::Object::toString}(){() →* core::String*};
+  core::Function* foo = () → Null {
+    () →* void f;
+    f.{core::Object::toString}(){() →* core::String*};
+  };
+  self2::C::test();
+  new self2::C::•().{self2::C::test2}(){() →* void};
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41498b.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue41498b.dart.weak.modular.expect
new file mode 100644
index 0000000..3af3c21
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41498b.dart.weak.modular.expect
@@ -0,0 +1,102 @@
+library opted_out_lib;
+import self as self;
+import "dart:core" as core;
+import "issue41498b_lib.dart" as iss;
+
+import "org-dartlang-testcase:///issue41498b_lib.dart" as opt_in;
+
+typedef LegacyFoo = () →* void;
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  static method test() → void {
+    () →* void f;
+    f.{core::Object::toString}(){() →* core::String*};
+  }
+  method test2() → void {
+    () →* void f;
+    f.{core::Object::toString}(){() →* core::String*};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  () →* void f;
+  f.{core::Object::toString}(){() →* core::String*};
+  core::Function* foo = () → Null {
+    () →* void f;
+    f.{core::Object::toString}(){() →* core::String*};
+  };
+  self::C::test();
+  new self::C::•().{self::C::test2}(){() →* void};
+}
+static method main() → dynamic {
+  iss::main();
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41498b_lib.dart:11:5: Error: Non-nullable variable 'f' must be assigned before it can be used.
+//     f.toString(); // error
+//     ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41498b_lib.dart:17:5: Error: Non-nullable variable 'f' must be assigned before it can be used.
+//     f.toString(); // error
+//     ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41498b_lib.dart:24:3: Error: Non-nullable variable 'f' must be assigned before it can be used.
+//   f.toString(); // error
+//   ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41498b_lib.dart:29:5: Error: Non-nullable variable 'f' must be assigned before it can be used.
+//     f.toString(); // error
+//     ^
+//
+import self as iss;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue41498b.dart";
+
+class C extends core::Object {
+  synthetic constructor •() → iss::C
+    : super core::Object::•()
+    ;
+  static method test() → void {
+    () → void f;
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41498b_lib.dart:11:5: Error: Non-nullable variable 'f' must be assigned before it can be used.
+    f.toString(); // error
+    ^" in f.{core::Object::toString}(){() → core::String};
+  }
+  method test2() → void {
+    () → void f;
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41498b_lib.dart:17:5: Error: Non-nullable variable 'f' must be assigned before it can be used.
+    f.toString(); // error
+    ^" in f.{core::Object::toString}(){() → core::String};
+  }
+}
+static method test() → dynamic {
+  () → void f;
+  invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41498b_lib.dart:24:3: Error: Non-nullable variable 'f' must be assigned before it can be used.
+  f.toString(); // error
+  ^" in f.{core::Object::toString}(){() → core::String};
+  core::Function foo = () → Null {
+    () → void f;
+    invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41498b_lib.dart:29:5: Error: Non-nullable variable 'f' must be assigned before it can be used.
+    f.toString(); // error
+    ^" in f.{core::Object::toString}(){() → core::String};
+  };
+  iss::C::test();
+  new iss::C::•().{iss::C::test2}(){() → void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41499.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue41499.dart.weak.modular.expect
new file mode 100644
index 0000000..63d713b0
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41499.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41499.dart:8:20: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+//   static LegacyFoo sTest() {}
+//                    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41499.dart:10:13: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+//   LegacyFoo mTest() {}
+//             ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41499.dart:12:17: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+//   LegacyFoo get gTest {}
+//                 ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41499.dart:15:11: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+// LegacyFoo test() {}
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue41499_lib.dart";
+
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+  static method sTest() → () → void {
+    return invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41499.dart:8:20: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+  static LegacyFoo sTest() {}
+                   ^" in null;
+  }
+  method mTest() → () → void {
+    return invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41499.dart:10:13: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+  LegacyFoo mTest() {}
+            ^" in null;
+  }
+  get gTest() → () → void {
+    return invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41499.dart:12:17: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+  LegacyFoo get gTest {}
+                ^" in null;
+  }
+}
+static method test() → () → void {
+  return invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41499.dart:15:11: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+LegacyFoo test() {}
+          ^" in null;
+}
+static method main() → dynamic {}
+
+library;
+import self as self2;
+
+typedef LegacyFoo = () →* void;
+static method test(() →* void f) → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41499b.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue41499b.dart.weak.modular.expect
new file mode 100644
index 0000000..e46d2e6
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41499b.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library;
+import self as self;
+
+import "org-dartlang-testcase:///issue41499b_lib.dart" as opt_in;
+
+typedef LegacyFoo = () →* void;
+static method test(() →* void f) → dynamic {}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41499b_lib.dart:8:20: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+//   static LegacyFoo sTest() {}
+//                    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41499b_lib.dart:10:13: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+//   LegacyFoo mTest() {}
+//             ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41499b_lib.dart:12:17: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+//   LegacyFoo get gTest {}
+//                 ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41499b_lib.dart:15:11: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+// LegacyFoo test() {}
+//           ^
+//
+import self as self2;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue41499b.dart";
+
+class C extends core::Object {
+  synthetic constructor •() → self2::C
+    : super core::Object::•()
+    ;
+  static method sTest() → () → void {
+    return invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41499b_lib.dart:8:20: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+  static LegacyFoo sTest() {}
+                   ^" in null;
+  }
+  method mTest() → () → void {
+    return invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41499b_lib.dart:10:13: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+  LegacyFoo mTest() {}
+            ^" in null;
+  }
+  get gTest() → () → void {
+    return invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41499b_lib.dart:12:17: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+  LegacyFoo get gTest {}
+                ^" in null;
+  }
+}
+static method test() → () → void {
+  return invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41499b_lib.dart:15:11: Error: A non-null value must be returned since the return type 'void Function()' doesn't allow null.
+LegacyFoo test() {}
+          ^" in null;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41567.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue41567.dart.weak.modular.expect
new file mode 100644
index 0000000..810b007
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41567.dart.weak.modular.expect
@@ -0,0 +1,75 @@
+//
+// Problems in component:
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41567.dart:13:7: Error: 'in3' can't implement both 'A<int>' and 'A<dynamic>'
+//  - 'A' is from 'pkg/front_end/testcases/nnbd_mixed/issue41567_lib.dart'.
+// class in3 extends out_int implements B {} // error
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41567.dart:15:7: Error: 'in4' can't implement both 'A<dynamic>' and 'A<int>'
+//  - 'A' is from 'pkg/front_end/testcases/nnbd_mixed/issue41567_lib.dart'.
+// class in4 extends B implements out_int {} // error
+//       ^
+//
+library /*isNonNullableByDefault*/;
+import self as self;
+import "issue41567_lib.dart" as iss;
+
+import "org-dartlang-testcase:///issue41567_lib.dart";
+
+class B extends iss::A<dynamic> {
+  synthetic constructor •() → self::B
+    : super iss::A::•()
+    ;
+}
+class in1 extends iss::out_Object implements self::B {
+  synthetic constructor •() → self::in1
+    : super iss::out_Object::•()
+    ;
+}
+class in2 extends self::B implements iss::out_Object {
+  synthetic constructor •() → self::in2
+    : super self::B::•()
+    ;
+}
+class in3 extends iss::out_int implements self::B {
+  synthetic constructor •() → self::in3
+    : super iss::out_int::•()
+    ;
+}
+class in4 extends self::B implements iss::out_int {
+  synthetic constructor •() → self::in4
+    : super self::B::•()
+    ;
+}
+static method main() → dynamic {}
+
+library;
+import self as iss;
+import "dart:core" as core;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → iss::A<iss::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class out_int extends iss::A<core::int*> {
+  synthetic constructor •() → iss::out_int*
+    : super iss::A::•()
+    ;
+}
+class out_Object extends iss::A<core::Object*> {
+  synthetic constructor •() → iss::out_Object*
+    : super iss::A::•()
+    ;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41597.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue41597.dart.weak.modular.expect
new file mode 100644
index 0000000..0178674
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41597.dart.weak.modular.expect
@@ -0,0 +1,128 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41597.dart:8:6: Error: 'x' is already declared in this scope.
+// bool x;
+//      ^
+// pkg/front_end/testcases/nnbd_mixed/issue41597.dart:7:6: Context: Previous declaration of 'x'.
+// bool x;
+//      ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41597.dart:8:6: Error: Field 'x' should be initialized because its type 'bool' doesn't allow null.
+// bool x;
+//      ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41597.dart:7:6: Error: Field 'x' should be initialized because its type 'bool' doesn't allow null.
+// bool x;
+//      ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41597.dart:11:9: Error: Can't use 'x' because it is declared more than once.
+//   print(x);
+//         ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41597.dart:12:9: Error: Can't use 'x' because it is declared more than once.
+//   print(x!);
+//         ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41597.dart:13:10: Error: Can't use 'x' because it is declared more than once.
+//   print(!x);
+//          ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41597.dart:18:12: Error: Can't use 'super' as an expression.
+// To delegate a constructor to a super constructor, put the super call as an initializer.
+//   C.c1() : super()!;
+//            ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41597.dart:18:19: Error: Expected an initializer.
+//   C.c1() : super()!;
+//                   ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue41597_lib.dart";
+
+class C extends core::Object {
+  constructor c0() → self::C
+    : super core::Object::•()
+    ;
+  constructor c1() → self::C
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41597.dart:18:12: Error: Can't use 'super' as an expression.
+To delegate a constructor to a super constructor, put the super call as an initializer.
+  C.c1() : super()!;
+           ^"!
+    ;
+}
+static field core::bool x;
+static method errors() → dynamic {
+  core::print(invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41597.dart:11:9: Error: Can't use 'x' because it is declared more than once.
+  print(x);
+        ^");
+  core::print(invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41597.dart:12:9: Error: Can't use 'x' because it is declared more than once.
+  print(x!);
+        ^"!);
+  core::print(!invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41597.dart:13:10: Error: Can't use 'x' because it is declared more than once.
+  print(!x);
+         ^");
+}
+static method main() → dynamic {}
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41597_lib.dart:8:6: Error: Expected an identifier, but got '.'.
+// Try inserting an identifier before '.'.
+//   c?..f;
+//      ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41597_lib.dart:8:6: Error: Expected an identifier, but got ''.
+// Try inserting an identifier before ''.
+//   c?..f;
+//      ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41597_lib.dart:9:7: Error: Expected an identifier, but got '.'.
+// Try inserting an identifier before '.'.
+//   !c?..f;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41597_lib.dart:9:7: Error: Expected an identifier, but got ''.
+// Try inserting an identifier before ''.
+//   !c?..f;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41597_lib.dart:10:6: Error: Expected an identifier, but got '.'.
+// Try inserting an identifier before '.'.
+//   c?..f!;
+//      ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41597_lib.dart:10:6: Error: Expected an identifier, but got ''.
+// Try inserting an identifier before ''.
+//   c?..f!;
+//      ^
+//
+// pkg/front_end/testcases/nnbd_mixed/issue41597_lib.dart:10:8: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+//   c?..f!;
+//        ^
+// pkg/front_end/testcases/nnbd_mixed/issue41597_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.6
+// ^^^^^^^^^^^^
+//
+import self as self2;
+
+static method errors(dynamic c) → dynamic {
+  invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41597_lib.dart:8:6: Error: Expected an identifier, but got ''.
+Try inserting an identifier before ''.
+  c?..f;
+     ^"{<invalid>}.f;
+  !invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41597_lib.dart:9:7: Error: Expected an identifier, but got ''.
+Try inserting an identifier before ''.
+  !c?..f;
+      ^"{<invalid>}.f;
+  invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue41597_lib.dart:10:6: Error: Expected an identifier, but got ''.
+Try inserting an identifier before ''.
+  c?..f!;
+     ^"{<invalid>}.f!;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41602.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue41602.dart.weak.modular.expect
new file mode 100644
index 0000000..fd8e4a3
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41602.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library;
+import self as self;
+import "dart:async" as asy;
+
+static method returnFutureOfVoid() → asy::Future<void>* async {}
+static method returnVoid() → void {}
+static method returnVoidAsync() → void async {}
+static method main() → dynamic async {
+  await self::returnVoid();
+  await self::returnFutureOfVoid();
+  await self::returnVoidAsync();
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue41657.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue41657.dart.weak.modular.expect
new file mode 100644
index 0000000..45aac72
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue41657.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static final field core::bool isLegacySubtyping1a = #C1 is{ForNonNullableByDefault} core::List<core::int>;
+static const field core::bool isLegacySubtyping1b = #C2;
+static final field core::bool isLegacySubtyping2a = #C3 is{ForNonNullableByDefault} core::List<core::int>;
+static const field core::bool isLegacySubtyping2b = #C2;
+static final field core::List<core::int> assertLegacySubtyping1a = #C1 as{ForNonNullableByDefault} core::List<core::int>;
+static const field core::List<core::int> assertLegacySubtyping1b = #C1;
+static final field core::List<core::int> assertLegacySubtyping2a = #C3 as{ForNonNullableByDefault} core::List<core::int>;
+static const field core::List<core::int> assertLegacySubtyping2b = #C3;
+static method main() → void {
+  self::expect(self::isLegacySubtyping1a, #C2);
+  self::expect(self::isLegacySubtyping2a, #C2);
+  self::expect(self::assertLegacySubtyping1a, #C1);
+  self::expect(self::assertLegacySubtyping2a, #C3);
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+constants  {
+  #C1 = <Null>[]
+  #C2 = true
+  #C3 = <core::int?>[]
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue42003.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue42003.dart.weak.modular.expect
new file mode 100644
index 0000000..cbd12a1
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue42003.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "issue42003_lib.dart" as iss;
+
+import "org-dartlang-testcase:///issue42003_lib.dart";
+
+static method main() → dynamic {
+  let final core::String* #t1 = iss::returnString() in #t1 == null ?{core::int?} null : #t1{core::String}.{core::String::length}{core::int};
+}
+
+library;
+import self as iss;
+import "dart:core" as core;
+
+static method returnString() → core::String*
+  return "foo";
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue42181.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue42181.dart.weak.modular.expect
new file mode 100644
index 0000000..8e2527a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue42181.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/issue42181.dart:10:9: Error: The value 'null' can't be assigned to a variable of type 'int Function(int)' because 'int Function(int)' is not nullable.
+//   F f = null; // Static error
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue42181_lib.dart";
+
+static method f1(core::int x) → core::int?
+  return x;
+static method test() → void {
+  (core::int*) → core::int* f = invalid-expression "pkg/front_end/testcases/nnbd_mixed/issue42181.dart:10:9: Error: The value 'null' can't be assigned to a variable of type 'int Function(int)' because 'int Function(int)' is not nullable.
+  F f = null; // Static error
+        ^" in null as{TypeError,ForNonNullableByDefault} (core::int*) → core::int*;
+  f = #C1;
+}
+static method main() → dynamic {}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+typedef F = (core::int*) →* core::int*;
+
+constants  {
+  #C1 = static-tearoff self::f1
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue42387/scheduler_tester.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue42387/scheduler_tester.dart.weak.modular.expect
new file mode 100644
index 0000000..35340a8
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue42387/scheduler_tester.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library;
+import self as self;
+import "foundation_binding_lib.dart" as fou;
+import "scheduler_binding_lib.dart" as sch;
+import "dart:core" as core;
+import "dart:async" as asy;
+import "services_binding_lib.dart" as ser;
+
+import "org-dartlang-testcase:///foundation_lib.dart";
+import "org-dartlang-testcase:///services_lib.dart";
+import "org-dartlang-testcase:///scheduler_lib.dart";
+
+abstract class _TestSchedulerBinding&BindingBase&SchedulerBinding = fou::BindingBase with sch::SchedulerBinding /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_TestSchedulerBinding&BindingBase&SchedulerBinding*
+    : super fou::BindingBase::•()
+    ;
+  abstract member-signature method registerSignalServiceExtension({core::String* name, () →* asy::Future<Null>* callback}) → void; -> fou::BindingBase::registerSignalServiceExtension
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _TestSchedulerBinding&BindingBase&SchedulerBinding&ServicesBinding = self::_TestSchedulerBinding&BindingBase&SchedulerBinding with ser::ServicesBinding /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_TestSchedulerBinding&BindingBase&SchedulerBinding&ServicesBinding*
+    : super self::_TestSchedulerBinding&BindingBase&SchedulerBinding::•()
+    ;
+}
+class TestSchedulerBinding extends self::_TestSchedulerBinding&BindingBase&SchedulerBinding&ServicesBinding {
+  synthetic constructor •() → self::TestSchedulerBinding*
+    : super self::_TestSchedulerBinding&BindingBase&SchedulerBinding&ServicesBinding::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue42660.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue42660.dart.weak.modular.expect
new file mode 100644
index 0000000..9f4f0a5
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue42660.dart.weak.modular.expect
@@ -0,0 +1,65 @@
+library;
+import self as self;
+import "issue42660_lib.dart" as iss;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue42660_lib.dart";
+
+static method main() → void {
+  iss::E|m(iss::f());
+  iss::E|m(#C1(){() →* core::int*});
+  iss::E|m(iss::p);
+  iss::Class<dynamic>* c = new iss::Class::•<dynamic>();
+  iss::E|m(c.{iss::Class::f}(){() →* core::int*});
+  iss::E|m(c.{iss::Class::f}{() →* core::int*}(){() →* core::int*});
+  iss::E|m(c.{iss::Class::p}{core::int*});
+  iss::E|m(c.{iss::Class::[]}(0){(core::int*) →* core::int*});
+  iss::E|m(c.{iss::Class::unary-}(){() →* core::int*});
+  iss::E|m(c.{iss::Class::+}(4){(core::Object*) →* core::int*});
+  let final iss::Class<dynamic>* #t1 = c in block {
+    iss::E|m(#t1.{iss::Class::p}{core::int*});
+    iss::E|m(#t1.{iss::Class::f}(){() →* core::int*});
+    iss::E|m(#t1.{iss::Class::[]}(0){(core::int*) →* core::int*});
+  } =>#t1;
+  let final iss::Class<dynamic>* #t2 = new iss::Class::•<dynamic>() in block {
+    iss::E|m(#t2.{iss::Class::p}{core::int*});
+    iss::E|m(#t2.{iss::Class::f}(){() →* core::int*});
+    iss::E|m(#t2.{iss::Class::[]}(0){(core::int*) →* core::int*});
+  } =>#t2;
+}
+
+library /*isNonNullableByDefault*/;
+import self as iss;
+import "dart:core" as core;
+
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → iss::Class<iss::Class::T%>
+    : super core::Object::•()
+    ;
+  method f() → core::int?
+    return 4;
+  get p() → core::int?
+    return 4;
+  operator [](core::int index) → core::int?
+    return 4;
+  operator unary-() → core::int?
+    return 4;
+  operator +(core::Object? other) → core::int?
+    return 4;
+}
+extension E on core::int {
+  method m = iss::E|m;
+  tearoff m = iss::E|get#m;
+}
+static method E|m(lowered final core::int #this) → core::String
+  return "m";
+static method E|get#m(lowered final core::int #this) → () → core::String
+  return () → core::String => iss::E|m(#this);
+static method f() → core::int?
+  return 4;
+static get p() → core::int?
+  return 4;
+
+constants  {
+  #C1 = static-tearoff iss::f
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue42792.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue42792.dart.weak.modular.expect
new file mode 100644
index 0000000..6cabc1e
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue42792.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "issue42792_lib.dart" as iss;
+
+import "org-dartlang-testcase:///issue42792_lib.dart";
+
+abstract class M<T extends core::Object? = dynamic> extends iss::A<self::M::T%> /*isMixinDeclaration*/  {
+}
+abstract class _B&A&M = iss::A<core::int> with self::M<core::int> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_B&A&M
+    : super iss::A::•()
+    ;
+}
+class B extends self::_B&A&M {
+  synthetic constructor •() → self::B
+    : super self::_B&A&M::•()
+    ;
+}
+static method main() → void {}
+
+library;
+import self as iss;
+import "dart:core" as core;
+
+abstract class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → iss::A<iss::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue42836.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue42836.dart.weak.modular.expect
new file mode 100644
index 0000000..f87710d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue42836.dart.weak.modular.expect
@@ -0,0 +1,73 @@
+library;
+import self as self;
+import "issue42836_lib.dart" as iss;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue42836_lib.dart";
+
+class Legacy extends iss::Generic<core::int*> {
+  synthetic constructor •() → self::Legacy*
+    : super iss::Generic::•()
+    ;
+  method legacyMethod() → core::int*
+    return 3;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field self::Legacy* legacyInstance = new self::Legacy::•();
+static method test(core::bool* b) → dynamic {
+  self::Legacy* a1 = b ?{self::Legacy*} self::legacyInstance : self::legacyInstance;
+  iss::Generic<core::int*>* a2 = b ?{iss::Generic<core::int*>*} self::legacyInstance : iss::nonNullableInstance;
+  iss::Generic<core::int*>* a3 = b ?{iss::Generic<core::int*>*} self::legacyInstance : iss::nullableInstance;
+  iss::Generic<core::int*>* b1 = b ?{iss::Generic<core::int*>*} iss::nonNullableInstance : self::legacyInstance;
+  iss::NonNullable* b2 = b ?{iss::NonNullable*} iss::nonNullableInstance : iss::nonNullableInstance;
+  iss::Generic<core::int*>* b3 = b ?{iss::Generic<core::int*>*} iss::nonNullableInstance : iss::nullableInstance;
+  iss::Generic<core::int*>* c1 = b ?{iss::Generic<core::int*>*} iss::nullableInstance : self::legacyInstance;
+  iss::Generic<core::int*>* c2 = b ?{iss::Generic<core::int*>*} iss::nullableInstance : iss::nonNullableInstance;
+  iss::Nullable* c3 = b ?{iss::Nullable*} iss::nullableInstance : iss::nullableInstance;
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as iss;
+import "dart:core" as core;
+import "issue42836.dart" as self;
+
+import "org-dartlang-testcase:///issue42836.dart";
+
+class Generic<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → iss::Generic<iss::Generic::T%>
+    : super core::Object::•()
+    ;
+}
+class NonNullable extends iss::Generic<core::int> {
+  synthetic constructor •() → iss::NonNullable
+    : super iss::Generic::•()
+    ;
+}
+class Nullable extends iss::Generic<core::int?> {
+  synthetic constructor •() → iss::Nullable
+    : super iss::Generic::•()
+    ;
+}
+static field iss::NonNullable nonNullableInstance = new iss::NonNullable::•();
+static field iss::Nullable nullableInstance = new iss::Nullable::•();
+static method test(core::bool b) → dynamic {
+  self::Legacy a1 = b ?{self::Legacy*} self::legacyInstance : self::legacyInstance;
+  core::Object a2 = b ?{core::Object*} self::legacyInstance : iss::nonNullableInstance;
+  core::Object a3 = b ?{core::Object*} self::legacyInstance : iss::nullableInstance;
+  core::Object b1 = b ?{core::Object*} iss::nonNullableInstance : self::legacyInstance;
+  iss::NonNullable b2 = b ?{iss::NonNullable} iss::nonNullableInstance : iss::nonNullableInstance;
+  core::Object b3 = b ?{core::Object} iss::nonNullableInstance : iss::nullableInstance;
+  core::Object c1 = b ?{core::Object*} iss::nullableInstance : self::legacyInstance;
+  core::Object c2 = b ?{core::Object} iss::nullableInstance : iss::nonNullableInstance;
+  iss::Nullable c3 = b ?{iss::Nullable} iss::nullableInstance : iss::nullableInstance;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue43988/main.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue43988/main.dart.weak.modular.expect
new file mode 100644
index 0000000..e31e167
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue43988/main.dart.weak.modular.expect
@@ -0,0 +1,119 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "main_lib.dart" as mai;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+abstract class _E1&Object&A = core::Object with mai::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E1&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{mai::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _E1&Object&A&D = self::_E1&Object&A with mai::D /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E1&Object&A&D*
+    : super self::_E1&Object&A::•()
+    ;
+  forwarding-stub method method(covariant-by-declaration core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{self::_E1&Object&A::method}(i, s: s);
+}
+class E1 extends self::_E1&Object&A&D {
+  synthetic constructor •() → self::E1*
+    : super self::_E1&Object&A&D::•()
+    ;
+}
+abstract class _E2&Object&A = core::Object with mai::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E2&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{mai::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E2 = self::_E2&Object&A with mai::D /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::E2*
+    : super self::_E2&Object&A::•()
+    ;
+  forwarding-stub method method(covariant-by-declaration core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{self::_E2&Object&A::method}(i, s: s);
+}
+abstract class _E3&Object&A = core::Object with mai::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E3&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{mai::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E3 = self::_E3&Object&A with mai::F /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::E3*
+    : super self::_E3&Object&A::•()
+    ;
+}
+abstract class C6 extends mai::C3 implements mai::C4 {
+  synthetic constructor •() → self::C6*
+    : super mai::C3::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract forwarding-stub method method2([covariant-by-declaration core::String* a]) → dynamic;
+}
+abstract class C8 extends mai::C5 implements mai::C7 {
+  synthetic constructor •() → self::C8*
+    : super mai::C5::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract forwarding-stub method method2([covariant-by-declaration core::String* a, core::num* b]) → dynamic;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = "hello"
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue43988/main.no_link.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue43988/main.no_link.dart.weak.modular.expect
new file mode 100644
index 0000000..76b963e
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue43988/main.no_link.dart.weak.modular.expect
@@ -0,0 +1,188 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "main_lib.dart" as mai;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+abstract class _E1&Object&A = core::Object with mai::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E1&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{mai::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _E1&Object&A&D = self::_E1&Object&A with mai::D /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E1&Object&A&D*
+    : super self::_E1&Object&A::•()
+    ;
+  forwarding-stub method method(covariant-by-declaration core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{self::_E1&Object&A::method}(i, s: s);
+}
+class E1 extends self::_E1&Object&A&D {
+  synthetic constructor •() → self::E1*
+    : super self::_E1&Object&A&D::•()
+    ;
+}
+abstract class _E2&Object&A = core::Object with mai::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E2&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{mai::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E2 = self::_E2&Object&A with mai::D /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::E2*
+    : super self::_E2&Object&A::•()
+    ;
+  forwarding-stub method method(covariant-by-declaration core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{self::_E2&Object&A::method}(i, s: s);
+}
+abstract class _E3&Object&A = core::Object with mai::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_E3&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::num* i, {core::String* s = #C1}) → core::String*
+    return super.{mai::A::method}(i, s: s);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E3 = self::_E3&Object&A with mai::F /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::E3*
+    : super self::_E3&Object&A::•()
+    ;
+}
+abstract class C6 extends mai::C3 implements mai::C4 {
+  synthetic constructor •() → self::C6*
+    : super mai::C3::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract forwarding-stub method method2([covariant-by-declaration core::String* a]) → dynamic;
+}
+abstract class C8 extends mai::C5 implements mai::C7 {
+  synthetic constructor •() → self::C8*
+    : super mai::C5::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract forwarding-stub method method2([covariant-by-declaration core::String* a = #C2, core::num* b = #C2]) → dynamic;
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as mai;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  synthetic constructor •() → mai::Interface
+    : super core::Object::•()
+    ;
+  abstract method method(core::num i) → core::String;
+}
+abstract class Interface2 extends core::Object {
+  synthetic constructor •() → mai::Interface2
+    : super core::Object::•()
+    ;
+  abstract method method(covariant-by-declaration core::int i) → core::String;
+}
+abstract class A extends core::Object implements mai::Interface /*isMixinDeclaration*/  {
+  method method(core::num i, {core::String s = #C1}) → core::String
+    return s;
+}
+abstract class D extends core::Object implements mai::Interface, mai::Interface2 {
+  synthetic constructor •() → mai::D
+    : super core::Object::•()
+    ;
+  abstract forwarding-stub method method(covariant-by-declaration core::num i) → core::String;
+}
+abstract class F extends core::Object implements mai::Interface {
+  synthetic constructor •() → mai::F
+    : super core::Object::•()
+    ;
+}
+abstract class C1 extends core::Object {
+  synthetic constructor •() → mai::C1
+    : super core::Object::•()
+    ;
+  abstract method method2() → dynamic;
+}
+abstract class C2 extends core::Object {
+  synthetic constructor •() → mai::C2
+    : super core::Object::•()
+    ;
+  abstract method method2([core::String a = #C2]) → dynamic;
+}
+abstract class C3 extends core::Object implements mai::C1, mai::C2 {
+  synthetic constructor •() → mai::C3
+    : super core::Object::•()
+    ;
+  abstract member-signature method method2([core::String a = #C2]) → dynamic; -> mai::C2::method2
+}
+abstract class C4 extends core::Object {
+  synthetic constructor •() → mai::C4
+    : super core::Object::•()
+    ;
+  abstract method method2([covariant-by-declaration core::String a = #C2]) → dynamic;
+}
+abstract class C5 extends mai::C3 implements mai::C4 {
+  synthetic constructor •() → mai::C5
+    : super mai::C3::•()
+    ;
+  abstract forwarding-stub method method2([covariant-by-declaration core::String a = #C2]) → dynamic;
+}
+abstract class C7 extends core::Object {
+  synthetic constructor •() → mai::C7
+    : super core::Object::•()
+    ;
+  abstract method method2([core::String a = #C2, core::num b = #C2]) → dynamic;
+}
+
+constants  {
+  #C1 = "hello"
+  #C2 = null
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/issue46518.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/issue46518.dart.weak.modular.expect
new file mode 100644
index 0000000..c718f8d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/issue46518.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+import self as self;
+import "issue46518_lib.dart" as iss;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue46518_lib.dart";
+
+static method main() → void {
+  iss::checkOptedIn(#C1);
+}
+
+library /*isNonNullableByDefault*/;
+import self as iss;
+import "dart:core" as core;
+
+typedef NullableIntF = () → core::int?;
+static method _check(core::Type t1, core::Type t2) → void {
+  core::print("Opted in: identical(${t1}, ${t2}) == ${core::identical(t1, t2)}");
+  core::print("Opted in: (${t1} == ${t2}) == ${t1 =={core::Type::==}{(core::Object) → core::bool} t2}");
+}
+static method checkOptedIn(core::Type t) → void {
+  iss::_check(t, #C1);
+}
+
+constants  {
+  #C1 = TypeLiteralConstant(() →* core::int?)
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/literal_from_opt_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/literal_from_opt_in.dart.weak.modular.expect
new file mode 100644
index 0000000..6c3539d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/literal_from_opt_in.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "literal_from_opt_in_lib.dart" as lit;
+
+import "org-dartlang-testcase:///literal_from_opt_in_lib.dart";
+
+static method main() → dynamic {
+  core::List<lit::Const<core::int*>*>* l1 = #C3;
+  core::List<lit::Const<core::int*>*>* l2 = #C5;
+  core::List<lit::Const<core::int*>*>* l3 = #C8;
+  core::List<lit::Const<core::int*>*>* l4 = #C3;
+  core::List<lit::Const<core::int*>*>* l5 = #C9;
+}
+
+library /*isNonNullableByDefault*/;
+import self as lit;
+import "dart:core" as core;
+
+class Const<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field lit::Const::T% field;
+  const constructor •(lit::Const::T% field) → lit::Const<lit::Const::T%>
+    : lit::Const::field = field, super core::Object::•()
+    ;
+}
+static const field lit::Const<core::int> a = #C2;
+static const field lit::Const<core::int?> b = #C4;
+static const field lit::Const<core::int?> c = #C7;
+static const field lit::Const<core::int>? d = #C2;
+static const field lit::Const<core::int>? e = #C6;
+
+constants  {
+  #C1 = 0
+  #C2 = lit::Const<core::int*> {field:#C1}
+  #C3 = <lit::Const<core::int*>*>[#C2]
+  #C4 = lit::Const<core::int?> {field:#C1}
+  #C5 = <lit::Const<core::int*>*>[#C4]
+  #C6 = null
+  #C7 = lit::Const<core::int?> {field:#C6}
+  #C8 = <lit::Const<core::int*>*>[#C7]
+  #C9 = <lit::Const<core::int*>*>[#C6]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///literal_from_opt_in_lib.dart:
+- Const. (from org-dartlang-testcase:///literal_from_opt_in_lib.dart:8:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/nnbd_mixed/main_declaration.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/main_declaration.dart.weak.modular.expect
new file mode 100644
index 0000000..58118e1
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/main_declaration.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library;
+import self as self;
+
+import "org-dartlang-testcase:///main_declaration_lib.dart";
+
+static method main() → dynamic {}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+static method main(core::String* args) → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/member_inheritance_from_opt_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/member_inheritance_from_opt_in.dart.weak.modular.expect
new file mode 100644
index 0000000..9e000b7
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/member_inheritance_from_opt_in.dart.weak.modular.expect
@@ -0,0 +1,182 @@
+library;
+import self as self;
+import "member_inheritance_from_opt_in_lib.dart" as mem;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///member_inheritance_from_opt_in_lib.dart";
+
+class LegacyClass extends mem::Class implements mem::Interface {
+  field core::int* field3 = null;
+  field core::int* field4 = null;
+  field core::int* property7 = null;
+  field core::int* property8 = null;
+  synthetic constructor •() → self::LegacyClass*
+    : super mem::Class::•()
+    ;
+  method method3() → core::int*
+    return 0;
+  method method4() → core::int*
+    return 0;
+  method method6a(core::int* a, core::int* b) → core::int*
+    return 0;
+  method method6b(core::int* a, [core::int* b = #C1]) → core::int*
+    return 0;
+  method method6c([core::int* a = #C1, core::int* b = #C1]) → core::int*
+    return 0;
+  method method8a(core::int* a, {core::int* b = #C2}) → core::int*
+    return 0;
+  method method8b({core::int* a = #C1, core::int* b = #C2}) → core::int*
+    return 0;
+  method method10a(core::int* a, {core::int* b = #C1}) → core::int*
+    return 0;
+  method method10b({core::int* a = #C1, core::int* b = #C1}) → core::int*
+    return 0;
+  get getter3() → core::int*
+    return 0;
+  get getter4() → core::int*
+    return 0;
+  set setter3(core::int* value) → void {}
+  set setter4(core::int* value) → void {}
+  get property3() → core::int*
+    return 0;
+  set property3(core::int* value) → void {}
+  get property4() → core::int*
+    return 0;
+  set property4(core::int* value) → void {}
+  abstract member-signature get field1() → core::int*; -> mem::Class::field1
+  abstract member-signature set field1(core::int* value) → void; -> mem::Class::field1
+  abstract member-signature get field2() → core::int*; -> mem::Class::field2
+  abstract member-signature set field2(core::int* value) → void; -> mem::Class::field2
+  abstract member-signature get property1() → core::int*; -> mem::Class::property1
+  abstract member-signature set property1(core::int* value) → void; -> mem::Class::property1
+  abstract member-signature get property2() → core::int*; -> mem::Class::property2
+  abstract member-signature set property2(core::int* value) → void; -> mem::Class::property2
+  abstract member-signature get property5() → core::int*; -> mem::Class::property5
+  abstract member-signature set property5(core::int* value) → void; -> mem::Class::property5
+  abstract member-signature get property6() → core::int*; -> mem::Class::property6
+  abstract member-signature set property6(core::int* value) → void; -> mem::Class::property6
+  abstract member-signature method method1() → core::int*; -> mem::Class::method1
+  abstract member-signature method method2() → core::int*; -> mem::Class::method2
+  abstract member-signature method method5a(core::int* a, core::int* b) → core::int*; -> mem::Class::method5a
+  abstract member-signature method method5b(core::int* a, [core::int* b = #C1]) → core::int*; -> mem::Class::method5b
+  abstract member-signature method method5c([core::int* a = #C2, core::int* b = #C1]) → core::int*; -> mem::Class::method5c
+  abstract member-signature method method7a(core::int* a, {core::int* b = #C1}) → core::int*; -> mem::Class::method7a
+  abstract member-signature method method7b({core::int* a = #C2, core::int* b = #C1}) → core::int*; -> mem::Class::method7b
+  abstract member-signature method method9a(core::int* a, {core::int* b = #C1}) → core::int*; -> mem::Class::method9a
+  abstract member-signature method method9b({core::int* a = #C1, core::int* b = #C1}) → core::int*; -> mem::Class::method9b
+  abstract member-signature get getter1() → core::int*; -> mem::Class::getter1
+  abstract member-signature get getter2() → core::int*; -> mem::Class::getter2
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature set setter1(core::int* value) → void; -> mem::Class::setter1
+  abstract member-signature set setter2(core::int* value) → void; -> mem::Class::setter2
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as mem;
+import "dart:core" as core;
+
+abstract class Interface extends core::Object {
+  field core::int? field1 = null;
+  field core::int field2 = 0;
+  field core::int field3 = 0;
+  field core::int? field4 = null;
+  synthetic constructor •() → mem::Interface
+    : super core::Object::•()
+    ;
+  abstract method method1() → core::int?;
+  abstract method method2() → core::int;
+  abstract method method3() → core::int;
+  abstract method method4() → core::int?;
+  abstract method method5a(core::int a, core::int? b) → core::int;
+  abstract method method5b(core::int a, [core::int? b = #C1]) → core::int;
+  abstract method method5c([core::int a = #C2, core::int? b = #C1]) → core::int;
+  abstract method method6a(core::int? a, core::int b) → core::int?;
+  abstract method method6b(core::int? a, [core::int b = #C2]) → core::int?;
+  abstract method method6c([core::int? a = #C1, core::int b = #C2]) → core::int?;
+  abstract method method7a(core::int a, {core::int? b = #C1}) → core::int;
+  abstract method method7b({core::int a = #C2, core::int? b = #C1}) → core::int;
+  abstract method method8a(core::int? a, {core::int b = #C2}) → core::int?;
+  abstract method method8b({core::int? a = #C1, core::int b = #C2}) → core::int?;
+  abstract method method9a(core::int a, {required core::int? b = #C1}) → core::int;
+  abstract method method9b({required core::int a = #C1, required core::int? b = #C1}) → core::int;
+  abstract method method10a(core::int? a, {required core::int b = #C1}) → core::int?;
+  abstract method method10b({required core::int? a = #C1, required core::int b = #C1}) → core::int?;
+  abstract get getter1() → core::int?;
+  abstract get getter2() → core::int;
+  abstract get getter3() → core::int;
+  abstract get getter4() → core::int?;
+  abstract set setter1(core::int? value) → void;
+  abstract set setter2(core::int value) → void;
+  abstract set setter3(core::int value) → void;
+  abstract set setter4(core::int? value) → void;
+  abstract get property1() → core::int?;
+  abstract set property1(core::int? value) → void;
+  abstract get property2() → core::int;
+  abstract set property2(core::int value) → void;
+  abstract get property3() → core::int;
+  abstract set property3(core::int value) → void;
+  abstract get property4() → core::int?;
+  abstract set property4(core::int? value) → void;
+  abstract get property5() → core::int?;
+  abstract set property5(core::int? value) → void;
+  abstract get property6() → core::int;
+  abstract set property6(core::int value) → void;
+  abstract get property7() → core::int;
+  abstract set property7(core::int value) → void;
+  abstract get property8() → core::int?;
+  abstract set property8(core::int? value) → void;
+}
+class Class extends core::Object {
+  field core::int field1 = 0;
+  field core::int? field2 = null;
+  field core::int property5 = 0;
+  field core::int? property6 = null;
+  synthetic constructor •() → mem::Class
+    : super core::Object::•()
+    ;
+  method method1() → core::int
+    return 0;
+  method method2() → core::int?
+    return 0;
+  method method5a(core::int a, core::int? b) → core::int
+    return 0;
+  method method5b(core::int a, [core::int? b = #C1]) → core::int
+    return 0;
+  method method5c([core::int a = #C2, core::int? b = #C1]) → core::int
+    return 0;
+  method method7a(core::int a, {core::int? b = #C1}) → core::int
+    return 0;
+  method method7b({core::int a = #C2, core::int? b = #C1}) → core::int
+    return 0;
+  method method9a(core::int a, {required core::int? b = #C1}) → core::int
+    return 0;
+  method method9b({required core::int a = #C1, required core::int? b = #C1}) → core::int
+    return 0;
+  get getter1() → core::int
+    return 0;
+  get getter2() → core::int?
+    return 0;
+  set setter1(core::int value) → void {}
+  set setter2(core::int? value) → void {}
+  get property1() → core::int
+    return 0;
+  set property1(core::int value) → void {}
+  get property2() → core::int?
+    return 0;
+  set property2(core::int? value) → void {}
+}
+
+constants  {
+  #C1 = null
+  #C2 = 0
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/member_inheritance_from_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/member_inheritance_from_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..fc797ac
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/member_inheritance_from_opt_out.dart.weak.modular.expect
@@ -0,0 +1,266 @@
+library main /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "member_inheritance_from_opt_out_lib.dart" as opt;
+
+import "org-dartlang-testcase:///member_inheritance_from_opt_out_lib.dart";
+
+abstract class Interface extends core::Object {
+  field core::int field1 = 0;
+  field core::int? field2 = null;
+  field core::int property3 = 0;
+  field core::int? property4 = null;
+  synthetic constructor •() → self::Interface
+    : super core::Object::•()
+    ;
+  abstract method method1() → core::int;
+  abstract method method2() → core::int?;
+  abstract method method3a(core::int a, core::int b) → core::int;
+  abstract method method3b(core::int a, [core::int b = #C1]) → core::int;
+  abstract method method3c([core::int a = #C1, core::int b = #C1]) → core::int;
+  abstract method method4a(core::int? a, core::int? b) → core::int?;
+  abstract method method4b(core::int? a, [core::int? b = #C1]) → core::int?;
+  abstract method method4c([core::int? a = #C1, core::int? b = #C1]) → core::int?;
+  abstract method method5a(core::int a, {core::int b = #C2}) → core::int;
+  abstract method method5b({core::int a = #C2, core::int b = #C2}) → core::int;
+  abstract method method5c({required core::int a = #C1, required core::int b = #C1}) → core::int;
+  abstract method method6a(core::int? a, {core::int? b = #C1}) → core::int?;
+  abstract method method6b({core::int? a = #C1, core::int? b = #C1}) → core::int?;
+  abstract method method6c({required core::int? a = #C1, required core::int? b = #C1}) → core::int?;
+  abstract get getter1() → core::int;
+  abstract get getter2() → core::int?;
+  abstract set setter1(core::int value) → void;
+  abstract set setter2(core::int? value) → void;
+  abstract get field3() → core::int;
+  abstract set field3(core::int value) → void;
+  abstract get field4() → core::int?;
+  abstract set field4(core::int? value) → void;
+  abstract get property1() → core::int;
+  abstract set property1(core::int value) → void;
+  abstract get property2() → core::int?;
+  abstract set property2(core::int? value) → void;
+}
+class Class1 extends opt::LegacyClass {
+  synthetic constructor •() → self::Class1
+    : super opt::LegacyClass::•()
+    ;
+}
+class Class2a extends opt::LegacyClass implements self::Interface {
+  synthetic constructor •() → self::Class2a
+    : super opt::LegacyClass::•()
+    ;
+  abstract member-signature get field1() → core::int; -> opt::LegacyClass::field1
+  abstract member-signature set field1(core::int value) → void; -> opt::LegacyClass::field1
+  abstract member-signature get field2() → core::int?; -> opt::LegacyClass::field2
+  abstract member-signature set field2(core::int? value) → void; -> opt::LegacyClass::field2
+  abstract member-signature get field3() → core::int; -> opt::LegacyClass::field3
+  abstract member-signature set field3(core::int value) → void; -> opt::LegacyClass::field3
+  abstract member-signature get field4() → core::int?; -> opt::LegacyClass::field4
+  abstract member-signature set field4(core::int? value) → void; -> opt::LegacyClass::field4
+  abstract member-signature get property1() → core::int; -> opt::LegacyClass::property1
+  abstract member-signature set property1(core::int value) → void; -> opt::LegacyClass::property1
+  abstract member-signature get property2() → core::int?; -> opt::LegacyClass::property2
+  abstract member-signature set property2(core::int? value) → void; -> opt::LegacyClass::property2
+  abstract member-signature get property3() → core::int; -> opt::LegacyClass::property3
+  abstract member-signature set property3(core::int value) → void; -> opt::LegacyClass::property3
+  abstract member-signature get property4() → core::int?; -> opt::LegacyClass::property4
+  abstract member-signature set property4(core::int? value) → void; -> opt::LegacyClass::property4
+  abstract member-signature method method1() → core::int; -> opt::LegacyClass::method1
+  abstract member-signature method method2() → core::int?; -> opt::LegacyClass::method2
+  abstract member-signature method method3a(core::int a, core::int b) → core::int; -> opt::LegacyClass::method3a
+  abstract member-signature method method3b(core::int a, [core::int b = #C1]) → core::int; -> opt::LegacyClass::method3b
+  abstract member-signature method method3c([core::int a = #C1, core::int b = #C1]) → core::int; -> opt::LegacyClass::method3c
+  abstract member-signature method method4a(core::int? a, core::int? b) → core::int?; -> opt::LegacyClass::method4a
+  abstract member-signature method method4b(core::int? a, [core::int? b = #C1]) → core::int?; -> opt::LegacyClass::method4b
+  abstract member-signature method method4c([core::int? a = #C1, core::int? b = #C1]) → core::int?; -> opt::LegacyClass::method4c
+  abstract member-signature method method5a(core::int a, {core::int b = #C1}) → core::int; -> opt::LegacyClass::method5a
+  abstract member-signature method method5b({core::int a = #C1, core::int b = #C1}) → core::int; -> opt::LegacyClass::method5b
+  abstract member-signature method method6a(core::int? a, {core::int? b = #C1}) → core::int?; -> opt::LegacyClass::method6a
+  abstract member-signature method method6b({core::int? a = #C1, core::int? b = #C1}) → core::int?; -> opt::LegacyClass::method6b
+  abstract member-signature get getter1() → core::int; -> opt::LegacyClass::getter1
+  abstract member-signature get getter2() → core::int?; -> opt::LegacyClass::getter2
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+  abstract member-signature set setter1(core::int value) → void; -> opt::LegacyClass::setter1
+  abstract member-signature set setter2(core::int? value) → void; -> opt::LegacyClass::setter2
+}
+class Class2b extends opt::LegacyClass implements self::Interface {
+  field core::int field1 = 0;
+  field core::int? field2 = null;
+  field core::int property3 = 0;
+  field core::int? property4 = null;
+  synthetic constructor •() → self::Class2b
+    : super opt::LegacyClass::•()
+    ;
+  method method1() → core::int
+    return 0;
+  method method2() → core::int?
+    return 0;
+  method method3a(core::int a, core::int b) → core::int
+    return 0;
+  method method3b(core::int a, [core::int b = #C3]) → core::int
+    return 0;
+  method method3c([core::int a = #C3, core::int b = #C3]) → core::int
+    return 0;
+  method method4a(core::int? a, core::int? b) → core::int?
+    return 0;
+  method method4b(core::int? a, [core::int? b = #C1]) → core::int?
+    return 0;
+  method method4c([core::int? a = #C1, core::int? b = #C1]) → core::int?
+    return 0;
+  method method5a(core::int a, {core::int b = #C2}) → core::int
+    return 0;
+  method method5b({core::int a = #C2, core::int b = #C2}) → core::int
+    return 0;
+  method method5c({required core::int a = #C1, required core::int b = #C1}) → core::int
+    return 0;
+  method method6a(core::int? a, {core::int? b = #C1}) → core::int?
+    return 0;
+  method method6b({core::int? a = #C1, core::int? b = #C1}) → core::int?
+    return 0;
+  method method6c({required core::int? a = #C1, required core::int? b = #C1}) → core::int?
+    return 0;
+  get getter1() → core::int
+    return 0;
+  get getter2() → core::int?
+    return 0;
+  set setter1(core::int value) → void {}
+  set setter2(core::int? value) → void {}
+  get field3() → core::int
+    return 0;
+  set field3(core::int value) → void {}
+  get field4() → core::int?
+    return 0;
+  set field4(core::int? value) → void {}
+  get property1() → core::int
+    return 0;
+  set property1(core::int value) → void {}
+  get property2() → core::int?
+    return 0;
+  set property2(core::int? value) → void {}
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+}
+class Class3a extends opt::GenericLegacyClass<core::int> {
+  synthetic constructor •() → self::Class3a
+    : super opt::GenericLegacyClass::•()
+    ;
+}
+class Class3b extends opt::GenericLegacyClass<core::int?> {
+  synthetic constructor •() → self::Class3b
+    : super opt::GenericLegacyClass::•()
+    ;
+}
+class Class3c<S extends core::Object? = dynamic> extends opt::GenericLegacyClass<self::Class3c::S%> {
+  synthetic constructor •() → self::Class3c<self::Class3c::S%>
+    : super opt::GenericLegacyClass::•()
+    ;
+}
+static method main() → dynamic {}
+
+library opt_out;
+import self as opt;
+import "dart:core" as core;
+
+class LegacyClass extends core::Object {
+  field core::int* field1 = null;
+  field core::int* field2 = null;
+  field core::int* field3 = null;
+  field core::int* field4 = null;
+  synthetic constructor •() → opt::LegacyClass*
+    : super core::Object::•()
+    ;
+  method method1() → core::int*
+    return 0;
+  method method2() → core::int*
+    return 0;
+  method method3a(core::int* a, core::int* b) → core::int*
+    return 0;
+  method method3b(core::int* a, [core::int* b = #C1]) → core::int*
+    return 0;
+  method method3c([core::int* a = #C1, core::int* b = #C1]) → core::int*
+    return 0;
+  method method4a(core::int* a, core::int* b) → core::int*
+    return 0;
+  method method4b(core::int* a, [core::int* b = #C1]) → core::int*
+    return 0;
+  method method4c([core::int* a = #C1, core::int* b = #C1]) → core::int*
+    return 0;
+  method method5a(core::int* a, {core::int* b = #C1}) → core::int*
+    return 0;
+  method method5b({core::int* a = #C1, core::int* b = #C1}) → core::int*
+    return 0;
+  method method5c({core::int* a = #C1, core::int* b = #C1}) → core::int*
+    return 0;
+  method method6a(core::int* a, {core::int* b = #C1}) → core::int*
+    return 0;
+  method method6b({core::int* a = #C1, core::int* b = #C1}) → core::int*
+    return 0;
+  method method6c({core::int* a = #C1, core::int* b = #C1}) → core::int*
+    return 0;
+  get getter1() → core::int*
+    return 0;
+  get getter2() → core::int*
+    return 0;
+  set setter1(core::int* value) → void {}
+  set setter2(core::int* value) → void {}
+  get property1() → core::int*
+    return 0;
+  set property1(core::int* value) → void {}
+  get property2() → core::int*
+    return 0;
+  set property2(core::int* value) → void {}
+  get property3() → core::int*
+    return 0;
+  set property3(core::int* value) → void {}
+  get property4() → core::int*
+    return 0;
+  set property4(core::int* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class GenericLegacyClass<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → opt::GenericLegacyClass<opt::GenericLegacyClass::T*>*
+    : super core::Object::•()
+    ;
+  method method1() → opt::GenericLegacyClass::T*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+constants  {
+  #C1 = null
+  #C2 = 0
+  #C3 = 42
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart.weak.modular.expect
new file mode 100644
index 0000000..33ff672
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart.weak.modular.expect
@@ -0,0 +1,274 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:17:6: Error: The return type of the method 'SubInIn.nullableBad' is 'T?', which does not match the return type, 'int?', of the overridden method, 'SuperIn.nullableBad'.
+// Change to a subtype of 'int?'.
+//   T? nullableBad<T>(T t) => null;
+//      ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:10:8: Context: This is the overridden method ('nullableBad').
+//   int? nullableBad<T>(T t) => 1;
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:18:5: Error: The return type of the method 'SubInIn.nonNullableBad' is 'T', which does not match the return type, 'int', of the overridden method, 'SuperIn.nonNullableBad'.
+// Change to a subtype of 'int'.
+//   T nonNullableBad<T>(T t) => t;
+//     ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:11:7: Context: This is the overridden method ('nonNullableBad').
+//   int nonNullableBad<T>(T t) => 2;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:24:6: Error: The return type of the method 'SubOutIn.nullableBad' is 'T?', which does not match the return type, 'int', of the overridden method, 'SuperOut.nullableBad'.
+// Change to a subtype of 'int'.
+//   T? nullableBad<T>(T t) => null;
+//      ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:12:7: Context: This is the overridden method ('nullableBad').
+//   int nullableBad<T>(T t) => 1;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:25:5: Error: The return type of the method 'SubOutIn.nonNullableBad' is 'T', which does not match the return type, 'int', of the overridden method, 'SuperOut.nonNullableBad'.
+// Change to a subtype of 'int'.
+//   T nonNullableBad<T>(T t) => t;
+//     ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:13:7: Context: This is the overridden method ('nonNullableBad').
+//   int nonNullableBad<T>(T t) => 2;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:32:17: Error: A value of type 'double' can't be assigned to a variable of type 'int Function()?'.
+//   nullableVar = nonNullableVar;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:33:20: Error: A value of type 'int Function()?' can't be assigned to a variable of type 'double'.
+//   nonNullableVar = nullableVar;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:34:15: Error: A value of type 'int Function()?' can't be assigned to a variable of type 'String'.
+//   legacyVar = nullableVar;
+//               ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:35:17: Error: A value of type 'String' can't be assigned to a variable of type 'int Function()?'.
+//   nullableVar = legacyVar;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:36:20: Error: A value of type 'String' can't be assigned to a variable of type 'double'.
+//   nonNullableVar = legacyVar;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:37:15: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+//   legacyVar = nonNullableVar;
+//               ^
+//
+import self as self;
+import "dart:core" as core;
+import "messages_with_types_opt_out.dart" as mes;
+
+import "org-dartlang-testcase:///messages_with_types_opt_out.dart";
+
+class SuperIn extends core::Object {
+  synthetic constructor •() → self::SuperIn
+    : super core::Object::•()
+    ;
+  method nullableSame() → core::String?
+    return "foo";
+  method nonNullableSame() → core::String
+    return "bar";
+  method nullableBad<T extends core::Object? = dynamic>(self::SuperIn::nullableBad::T% t) → core::int?
+    return 1;
+  method nonNullableBad<T extends core::Object? = dynamic>(self::SuperIn::nonNullableBad::T% t) → core::int
+    return 2;
+}
+class SubInIn extends self::SuperIn {
+  synthetic constructor •() → self::SubInIn
+    : super self::SuperIn::•()
+    ;
+  method nullableSame() → core::String?
+    return "foo";
+  method nonNullableSame() → core::String
+    return "bar";
+  method nullableBad<T extends core::Object? = dynamic>(self::SubInIn::nullableBad::T% t) → self::SubInIn::nullableBad::T?
+    return null;
+  method nonNullableBad<T extends core::Object? = dynamic>(self::SubInIn::nonNullableBad::T% t) → self::SubInIn::nonNullableBad::T%
+    return t;
+}
+class SubOutIn extends mes::SuperOut {
+  synthetic constructor •() → self::SubOutIn
+    : super mes::SuperOut::•()
+    ;
+  method nullableSame() → core::String?
+    return "foo";
+  method nonNullableSame() → core::String
+    return "bar";
+  method nullableBad<T extends core::Object? = dynamic>(self::SubOutIn::nullableBad::T% t) → self::SubOutIn::nullableBad::T?
+    return null;
+  method nonNullableBad<T extends core::Object? = dynamic>(self::SubOutIn::nonNullableBad::T% t) → self::SubOutIn::nonNullableBad::T%
+    return t;
+}
+static field () →? core::int nullableVar = () → core::int => 3;
+static field core::double nonNullableVar = 4.0;
+static method testOptIn() → dynamic {
+  self::nullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:32:17: Error: A value of type 'double' can't be assigned to a variable of type 'int Function()?'.
+  nullableVar = nonNullableVar;
+                ^" in self::nonNullableVar as{TypeError,ForNonNullableByDefault} () →? core::int;
+  self::nonNullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:33:20: Error: A value of type 'int Function()?' can't be assigned to a variable of type 'double'.
+  nonNullableVar = nullableVar;
+                   ^" in self::nullableVar as{TypeError,ForNonNullableByDefault} core::double;
+  mes::legacyVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:34:15: Error: A value of type 'int Function()?' can't be assigned to a variable of type 'String'.
+  legacyVar = nullableVar;
+              ^" in self::nullableVar as{TypeError,ForNonNullableByDefault} core::String*;
+  self::nullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:35:17: Error: A value of type 'String' can't be assigned to a variable of type 'int Function()?'.
+  nullableVar = legacyVar;
+                ^" in mes::legacyVar as{TypeError,ForNonNullableByDefault} () →? core::int;
+  self::nonNullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:36:20: Error: A value of type 'String' can't be assigned to a variable of type 'double'.
+  nonNullableVar = legacyVar;
+                   ^" in mes::legacyVar as{TypeError,ForNonNullableByDefault} core::double;
+  mes::legacyVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:37:15: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+  legacyVar = nonNullableVar;
+              ^" in self::nonNullableVar as{TypeError,ForNonNullableByDefault} core::String*;
+}
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:19:5: Error: The return type of the method 'SubOutOut.nullableBad' is 'T', which does not match the return type, 'int', of the overridden method, 'SuperOut.nullableBad'.
+// Change to a subtype of 'int'.
+//   T nullableBad<T>(T t) => null;
+//     ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:12:7: Context: This is the overridden method ('nullableBad').
+//   int nullableBad<T>(T t) => 1;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:20:5: Error: The return type of the method 'SubOutOut.nonNullableBad' is 'T', which does not match the return type, 'int', of the overridden method, 'SuperOut.nonNullableBad'.
+// Change to a subtype of 'int'.
+//   T nonNullableBad<T>(T t) => t;
+//     ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:13:7: Context: This is the overridden method ('nonNullableBad').
+//   int nonNullableBad<T>(T t) => 2;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:26:5: Error: The return type of the method 'SubInOut.nullableBad' is 'T', which does not match the return type, 'int', of the overridden method, 'SuperIn.nullableBad'.
+// Change to a subtype of 'int'.
+//   T nullableBad<T>(T t) => null;
+//     ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:10:8: Context: This is the overridden method ('nullableBad').
+//   int? nullableBad<T>(T t) => 1;
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:27:5: Error: The return type of the method 'SubInOut.nonNullableBad' is 'T', which does not match the return type, 'int', of the overridden method, 'SuperIn.nonNullableBad'.
+// Change to a subtype of 'int'.
+//   T nonNullableBad<T>(T t) => t;
+//     ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:11:7: Context: This is the overridden method ('nonNullableBad').
+//   int nonNullableBad<T>(T t) => 2;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:33:17: Error: A value of type 'double' can't be assigned to a variable of type 'int Function()'.
+//   nullableVar = nonNullableVar;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:34:20: Error: A value of type 'int Function()' can't be assigned to a variable of type 'double'.
+//   nonNullableVar = nullableVar;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:35:15: Error: A value of type 'int Function()' can't be assigned to a variable of type 'String'.
+//   legacyVar = nullableVar;
+//               ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:36:17: Error: A value of type 'String' can't be assigned to a variable of type 'int Function()'.
+//   nullableVar = legacyVar;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:37:20: Error: A value of type 'String' can't be assigned to a variable of type 'double'.
+//   nonNullableVar = legacyVar;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:38:15: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+//   legacyVar = nonNullableVar;
+//               ^
+//
+import self as mes;
+import "dart:core" as core;
+import "messages_with_types_opt_in.dart" as self;
+
+import "org-dartlang-testcase:///messages_with_types_opt_in.dart";
+
+class SuperOut extends core::Object {
+  synthetic constructor •() → mes::SuperOut*
+    : super core::Object::•()
+    ;
+  method nullableSame() → core::String*
+    return "foo";
+  method nonNullableSame() → core::String*
+    return "bar";
+  method nullableBad<T extends core::Object* = dynamic>(mes::SuperOut::nullableBad::T* t) → core::int*
+    return 1;
+  method nonNullableBad<T extends core::Object* = dynamic>(mes::SuperOut::nonNullableBad::T* t) → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class SubOutOut extends mes::SuperOut {
+  synthetic constructor •() → mes::SubOutOut*
+    : super mes::SuperOut::•()
+    ;
+  method nullableSame() → core::String*
+    return "foo";
+  method nonNullableSame() → core::String*
+    return "bar";
+  method nullableBad<T extends core::Object* = dynamic>(mes::SubOutOut::nullableBad::T* t) → mes::SubOutOut::nullableBad::T*
+    return null;
+  method nonNullableBad<T extends core::Object* = dynamic>(mes::SubOutOut::nonNullableBad::T* t) → mes::SubOutOut::nonNullableBad::T*
+    return t;
+}
+class SubInOut extends self::SuperIn {
+  synthetic constructor •() → mes::SubInOut*
+    : super self::SuperIn::•()
+    ;
+  method nullableSame() → core::String*
+    return "foo";
+  method nonNullableSame() → core::String*
+    return "bar";
+  method nullableBad<T extends core::Object* = dynamic>(mes::SubInOut::nullableBad::T* t) → mes::SubInOut::nullableBad::T*
+    return null;
+  method nonNullableBad<T extends core::Object* = dynamic>(mes::SubInOut::nonNullableBad::T* t) → mes::SubInOut::nonNullableBad::T*
+    return t;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::String* legacyVar = "legacy";
+static method testOptOut() → dynamic {
+  self::nullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:33:17: Error: A value of type 'double' can't be assigned to a variable of type 'int Function()'.
+  nullableVar = nonNullableVar;
+                ^" in self::nonNullableVar as{TypeError} () →? core::int;
+  self::nonNullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:34:20: Error: A value of type 'int Function()' can't be assigned to a variable of type 'double'.
+  nonNullableVar = nullableVar;
+                   ^" in self::nullableVar as{TypeError} core::double;
+  mes::legacyVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:35:15: Error: A value of type 'int Function()' can't be assigned to a variable of type 'String'.
+  legacyVar = nullableVar;
+              ^" in self::nullableVar as{TypeError} core::String*;
+  self::nullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:36:17: Error: A value of type 'String' can't be assigned to a variable of type 'int Function()'.
+  nullableVar = legacyVar;
+                ^" in mes::legacyVar as{TypeError} () →? core::int;
+  self::nonNullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:37:20: Error: A value of type 'String' can't be assigned to a variable of type 'double'.
+  nonNullableVar = legacyVar;
+                   ^" in mes::legacyVar as{TypeError} core::double;
+  mes::legacyVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:38:15: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+  legacyVar = nonNullableVar;
+              ^" in self::nonNullableVar as{TypeError} core::String*;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..8a877f1
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart.weak.modular.expect
@@ -0,0 +1,274 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:19:5: Error: The return type of the method 'SubOutOut.nullableBad' is 'T', which does not match the return type, 'int', of the overridden method, 'SuperOut.nullableBad'.
+// Change to a subtype of 'int'.
+//   T nullableBad<T>(T t) => null;
+//     ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:12:7: Context: This is the overridden method ('nullableBad').
+//   int nullableBad<T>(T t) => 1;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:20:5: Error: The return type of the method 'SubOutOut.nonNullableBad' is 'T', which does not match the return type, 'int', of the overridden method, 'SuperOut.nonNullableBad'.
+// Change to a subtype of 'int'.
+//   T nonNullableBad<T>(T t) => t;
+//     ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:13:7: Context: This is the overridden method ('nonNullableBad').
+//   int nonNullableBad<T>(T t) => 2;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:26:5: Error: The return type of the method 'SubInOut.nullableBad' is 'T', which does not match the return type, 'int', of the overridden method, 'SuperIn.nullableBad'.
+// Change to a subtype of 'int'.
+//   T nullableBad<T>(T t) => null;
+//     ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:10:8: Context: This is the overridden method ('nullableBad').
+//   int? nullableBad<T>(T t) => 1;
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:27:5: Error: The return type of the method 'SubInOut.nonNullableBad' is 'T', which does not match the return type, 'int', of the overridden method, 'SuperIn.nonNullableBad'.
+// Change to a subtype of 'int'.
+//   T nonNullableBad<T>(T t) => t;
+//     ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:11:7: Context: This is the overridden method ('nonNullableBad').
+//   int nonNullableBad<T>(T t) => 2;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:33:17: Error: A value of type 'double' can't be assigned to a variable of type 'int Function()'.
+//   nullableVar = nonNullableVar;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:34:20: Error: A value of type 'int Function()' can't be assigned to a variable of type 'double'.
+//   nonNullableVar = nullableVar;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:35:15: Error: A value of type 'int Function()' can't be assigned to a variable of type 'String'.
+//   legacyVar = nullableVar;
+//               ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:36:17: Error: A value of type 'String' can't be assigned to a variable of type 'int Function()'.
+//   nullableVar = legacyVar;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:37:20: Error: A value of type 'String' can't be assigned to a variable of type 'double'.
+//   nonNullableVar = legacyVar;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:38:15: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+//   legacyVar = nonNullableVar;
+//               ^
+//
+import self as self;
+import "dart:core" as core;
+import "messages_with_types_opt_in.dart" as mes;
+
+import "org-dartlang-testcase:///messages_with_types_opt_in.dart";
+
+class SuperOut extends core::Object {
+  synthetic constructor •() → self::SuperOut*
+    : super core::Object::•()
+    ;
+  method nullableSame() → core::String*
+    return "foo";
+  method nonNullableSame() → core::String*
+    return "bar";
+  method nullableBad<T extends core::Object* = dynamic>(self::SuperOut::nullableBad::T* t) → core::int*
+    return 1;
+  method nonNullableBad<T extends core::Object* = dynamic>(self::SuperOut::nonNullableBad::T* t) → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class SubOutOut extends self::SuperOut {
+  synthetic constructor •() → self::SubOutOut*
+    : super self::SuperOut::•()
+    ;
+  method nullableSame() → core::String*
+    return "foo";
+  method nonNullableSame() → core::String*
+    return "bar";
+  method nullableBad<T extends core::Object* = dynamic>(self::SubOutOut::nullableBad::T* t) → self::SubOutOut::nullableBad::T*
+    return null;
+  method nonNullableBad<T extends core::Object* = dynamic>(self::SubOutOut::nonNullableBad::T* t) → self::SubOutOut::nonNullableBad::T*
+    return t;
+}
+class SubInOut extends mes::SuperIn {
+  synthetic constructor •() → self::SubInOut*
+    : super mes::SuperIn::•()
+    ;
+  method nullableSame() → core::String*
+    return "foo";
+  method nonNullableSame() → core::String*
+    return "bar";
+  method nullableBad<T extends core::Object* = dynamic>(self::SubInOut::nullableBad::T* t) → self::SubInOut::nullableBad::T*
+    return null;
+  method nonNullableBad<T extends core::Object* = dynamic>(self::SubInOut::nonNullableBad::T* t) → self::SubInOut::nonNullableBad::T*
+    return t;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::String* legacyVar = "legacy";
+static method testOptOut() → dynamic {
+  mes::nullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:33:17: Error: A value of type 'double' can't be assigned to a variable of type 'int Function()'.
+  nullableVar = nonNullableVar;
+                ^" in mes::nonNullableVar as{TypeError} () →? core::int;
+  mes::nonNullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:34:20: Error: A value of type 'int Function()' can't be assigned to a variable of type 'double'.
+  nonNullableVar = nullableVar;
+                   ^" in mes::nullableVar as{TypeError} core::double;
+  self::legacyVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:35:15: Error: A value of type 'int Function()' can't be assigned to a variable of type 'String'.
+  legacyVar = nullableVar;
+              ^" in mes::nullableVar as{TypeError} core::String*;
+  mes::nullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:36:17: Error: A value of type 'String' can't be assigned to a variable of type 'int Function()'.
+  nullableVar = legacyVar;
+                ^" in self::legacyVar as{TypeError} () →? core::int;
+  mes::nonNullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:37:20: Error: A value of type 'String' can't be assigned to a variable of type 'double'.
+  nonNullableVar = legacyVar;
+                   ^" in self::legacyVar as{TypeError} core::double;
+  self::legacyVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:38:15: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+  legacyVar = nonNullableVar;
+              ^" in mes::nonNullableVar as{TypeError} core::String*;
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:17:6: Error: The return type of the method 'SubInIn.nullableBad' is 'T?', which does not match the return type, 'int?', of the overridden method, 'SuperIn.nullableBad'.
+// Change to a subtype of 'int?'.
+//   T? nullableBad<T>(T t) => null;
+//      ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:10:8: Context: This is the overridden method ('nullableBad').
+//   int? nullableBad<T>(T t) => 1;
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:18:5: Error: The return type of the method 'SubInIn.nonNullableBad' is 'T', which does not match the return type, 'int', of the overridden method, 'SuperIn.nonNullableBad'.
+// Change to a subtype of 'int'.
+//   T nonNullableBad<T>(T t) => t;
+//     ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:11:7: Context: This is the overridden method ('nonNullableBad').
+//   int nonNullableBad<T>(T t) => 2;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:24:6: Error: The return type of the method 'SubOutIn.nullableBad' is 'T?', which does not match the return type, 'int', of the overridden method, 'SuperOut.nullableBad'.
+// Change to a subtype of 'int'.
+//   T? nullableBad<T>(T t) => null;
+//      ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:12:7: Context: This is the overridden method ('nullableBad').
+//   int nullableBad<T>(T t) => 1;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:25:5: Error: The return type of the method 'SubOutIn.nonNullableBad' is 'T', which does not match the return type, 'int', of the overridden method, 'SuperOut.nonNullableBad'.
+// Change to a subtype of 'int'.
+//   T nonNullableBad<T>(T t) => t;
+//     ^
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_out.dart:13:7: Context: This is the overridden method ('nonNullableBad').
+//   int nonNullableBad<T>(T t) => 2;
+//       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:32:17: Error: A value of type 'double' can't be assigned to a variable of type 'int Function()?'.
+//   nullableVar = nonNullableVar;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:33:20: Error: A value of type 'int Function()?' can't be assigned to a variable of type 'double'.
+//   nonNullableVar = nullableVar;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:34:15: Error: A value of type 'int Function()?' can't be assigned to a variable of type 'String'.
+//   legacyVar = nullableVar;
+//               ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:35:17: Error: A value of type 'String' can't be assigned to a variable of type 'int Function()?'.
+//   nullableVar = legacyVar;
+//                 ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:36:20: Error: A value of type 'String' can't be assigned to a variable of type 'double'.
+//   nonNullableVar = legacyVar;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:37:15: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+//   legacyVar = nonNullableVar;
+//               ^
+//
+import self as mes;
+import "dart:core" as core;
+import "messages_with_types_opt_out.dart" as self;
+
+import "org-dartlang-testcase:///messages_with_types_opt_out.dart";
+
+class SuperIn extends core::Object {
+  synthetic constructor •() → mes::SuperIn
+    : super core::Object::•()
+    ;
+  method nullableSame() → core::String?
+    return "foo";
+  method nonNullableSame() → core::String
+    return "bar";
+  method nullableBad<T extends core::Object? = dynamic>(mes::SuperIn::nullableBad::T% t) → core::int?
+    return 1;
+  method nonNullableBad<T extends core::Object? = dynamic>(mes::SuperIn::nonNullableBad::T% t) → core::int
+    return 2;
+}
+class SubInIn extends mes::SuperIn {
+  synthetic constructor •() → mes::SubInIn
+    : super mes::SuperIn::•()
+    ;
+  method nullableSame() → core::String?
+    return "foo";
+  method nonNullableSame() → core::String
+    return "bar";
+  method nullableBad<T extends core::Object? = dynamic>(mes::SubInIn::nullableBad::T% t) → mes::SubInIn::nullableBad::T?
+    return null;
+  method nonNullableBad<T extends core::Object? = dynamic>(mes::SubInIn::nonNullableBad::T% t) → mes::SubInIn::nonNullableBad::T%
+    return t;
+}
+class SubOutIn extends self::SuperOut {
+  synthetic constructor •() → mes::SubOutIn
+    : super self::SuperOut::•()
+    ;
+  method nullableSame() → core::String?
+    return "foo";
+  method nonNullableSame() → core::String
+    return "bar";
+  method nullableBad<T extends core::Object? = dynamic>(mes::SubOutIn::nullableBad::T% t) → mes::SubOutIn::nullableBad::T?
+    return null;
+  method nonNullableBad<T extends core::Object? = dynamic>(mes::SubOutIn::nonNullableBad::T% t) → mes::SubOutIn::nonNullableBad::T%
+    return t;
+}
+static field () →? core::int nullableVar = () → core::int => 3;
+static field core::double nonNullableVar = 4.0;
+static method testOptIn() → dynamic {
+  mes::nullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:32:17: Error: A value of type 'double' can't be assigned to a variable of type 'int Function()?'.
+  nullableVar = nonNullableVar;
+                ^" in mes::nonNullableVar as{TypeError,ForNonNullableByDefault} () →? core::int;
+  mes::nonNullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:33:20: Error: A value of type 'int Function()?' can't be assigned to a variable of type 'double'.
+  nonNullableVar = nullableVar;
+                   ^" in mes::nullableVar as{TypeError,ForNonNullableByDefault} core::double;
+  self::legacyVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:34:15: Error: A value of type 'int Function()?' can't be assigned to a variable of type 'String'.
+  legacyVar = nullableVar;
+              ^" in mes::nullableVar as{TypeError,ForNonNullableByDefault} core::String*;
+  mes::nullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:35:17: Error: A value of type 'String' can't be assigned to a variable of type 'int Function()?'.
+  nullableVar = legacyVar;
+                ^" in self::legacyVar as{TypeError,ForNonNullableByDefault} () →? core::int;
+  mes::nonNullableVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:36:20: Error: A value of type 'String' can't be assigned to a variable of type 'double'.
+  nonNullableVar = legacyVar;
+                   ^" in self::legacyVar as{TypeError,ForNonNullableByDefault} core::double;
+  self::legacyVar = invalid-expression "pkg/front_end/testcases/nnbd_mixed/messages_with_types_opt_in.dart:37:15: Error: A value of type 'double' can't be assigned to a variable of type 'String'.
+  legacyVar = nonNullableVar;
+              ^" in mes::nonNullableVar as{TypeError,ForNonNullableByDefault} core::String*;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/mixed_mixin.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/mixed_mixin.dart.weak.modular.expect
new file mode 100644
index 0000000..04e3fe5
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/mixed_mixin.dart.weak.modular.expect
@@ -0,0 +1,79 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "mixed_mixin_lib.dart" as mix;
+
+import "org-dartlang-testcase:///mixed_mixin_lib.dart";
+
+abstract class _C1&Object&B = core::Object with mix::B /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C1&Object&B*
+    : super core::Object::•()
+    ;
+  mixin-super-stub get a() → core::List<(core::int*) →* core::int*>*
+    return super.{mix::B::a};
+  mixin-super-stub set a(core::List<(core::int*) →* core::int*>* _) → void
+    return super.{mix::B::a} = _;
+  mixin-super-stub method m((core::int*) →* core::int* x) → (core::int*) →* core::int*
+    return super.{mix::B::m}(x);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C1 extends self::_C1&Object&B {
+  synthetic constructor •() → self::C1*
+    : super self::_C1&Object&B::•()
+    ;
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as mix;
+import "dart:core" as core;
+import "mixed_mixin.dart" as self;
+
+import "org-dartlang-testcase:///mixed_mixin.dart";
+
+class B extends core::Object {
+  synthetic constructor •() → mix::B
+    : super core::Object::•()
+    ;
+  get a() → core::List<(core::int) → core::int>
+    return <(core::int) → core::int>[];
+  set a(core::List<(core::int) → core::int> _) → void {}
+  method m((core::int) → core::int x) → (core::int) → core::int
+    return x;
+}
+class Bq extends core::Object {
+  synthetic constructor •() → mix::Bq
+    : super core::Object::•()
+    ;
+  get a() → core::List<(core::int?) → core::int?>
+    return <(core::int?) → core::int?>[];
+  set a(core::List<(core::int?) → core::int?> _) → void {}
+  method m((core::int?) → core::int? x) → (core::int?) → core::int?
+    return x;
+}
+class DiBq1 extends self::C1 implements mix::Bq {
+  synthetic constructor •() → mix::DiBq1
+    : super self::C1::•()
+    ;
+  abstract member-signature get a() → core::List<(core::int?) → core::int?>; -> self::_C1&Object&B::a
+  abstract member-signature set a(core::List<(core::int?) → core::int?> _) → void; -> self::_C1&Object&B::a
+  abstract member-signature method m((core::int?) → core::int? x) → (core::int?) → core::int?; -> self::_C1&Object&B::m
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/mixed_mode_hierarchy_generic_methods.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/mixed_mode_hierarchy_generic_methods.dart.weak.modular.expect
new file mode 100644
index 0000000..6a49d2f
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/mixed_mode_hierarchy_generic_methods.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "mixed_mode_hierarchy_generic_methods_lib.dart" as mix;
+import "dart:async" as asy;
+
+import "org-dartlang-testcase:///mixed_mode_hierarchy_generic_methods_lib.dart";
+import "dart:async";
+
+class B extends core::Object implements mix::A<core::int*> {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method then<B extends core::Object* = dynamic>() → asy::Future<self::B::then::B*>*
+    return asy::Future::value<self::B::then::B*>();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as mix;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+class A<R extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → mix::A<mix::A::R%>
+    : super core::Object::•()
+    ;
+  method then<T extends core::Object? = dynamic>() → asy::Future<mix::A::then::T%>
+    return asy::Future::value<mix::A::then::T%>();
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/mixin_from_dill2/main.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/mixin_from_dill2/main.dart.weak.modular.expect
new file mode 100644
index 0000000..f168a4e
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/mixin_from_dill2/main.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "main_lib.dart" as mai;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+abstract class RenderAnimatedOpacityMixin<T extends mai::RenderObject> extends mai::RenderObjectWithChildMixin<self::RenderAnimatedOpacityMixin::T> /*isMixinDeclaration*/  {
+}
+abstract class _RenderAnimatedOpacity&RenderProxyBox&RenderProxyBoxMixin = mai::RenderProxyBox with mai::RenderProxyBoxMixin<mai::RenderBox> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_RenderAnimatedOpacity&RenderProxyBox&RenderProxyBoxMixin
+    : super mai::RenderProxyBox::•()
+    ;
+  mixin-super-stub method hitTestChildren(mai::BoxHitTestResult result, {required mai::Offset position}) → core::bool
+    return super.{mai::RenderProxyBoxMixin::hitTestChildren}(result, position: position);
+}
+abstract class _RenderAnimatedOpacity&RenderProxyBox&RenderProxyBoxMixin&RenderAnimatedOpacityMixin = self::_RenderAnimatedOpacity&RenderProxyBox&RenderProxyBoxMixin with self::RenderAnimatedOpacityMixin<mai::RenderBox> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_RenderAnimatedOpacity&RenderProxyBox&RenderProxyBoxMixin&RenderAnimatedOpacityMixin
+    : super self::_RenderAnimatedOpacity&RenderProxyBox&RenderProxyBoxMixin::•()
+    ;
+}
+class RenderAnimatedOpacity extends self::_RenderAnimatedOpacity&RenderProxyBox&RenderProxyBoxMixin&RenderAnimatedOpacityMixin {
+  synthetic constructor •() → self::RenderAnimatedOpacity
+    : super self::_RenderAnimatedOpacity&RenderProxyBox&RenderProxyBoxMixin&RenderAnimatedOpacityMixin::•()
+    ;
+}
+static method main() → dynamic {
+  new self::RenderAnimatedOpacity::•();
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in.dart.weak.modular.expect
new file mode 100644
index 0000000..9f5295d
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "mixin_from_opt_in_lib.dart" as mix;
+
+import "org-dartlang-testcase:///mixin_from_opt_in_lib.dart";
+
+abstract class _Class&Object&Mixin = core::Object with mix::Mixin /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Class&Object&Mixin*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method method(core::int* i) → core::int*
+    return super.{mix::Mixin::method}(i);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Class extends self::_Class&Object&Mixin {
+  synthetic constructor •() → self::Class*
+    : super self::_Class&Object&Mixin::•()
+    ;
+}
+static method main() → dynamic {
+  core::print(new self::Class::•().{self::_Class&Object&Mixin::method}(null){(core::int*) →* core::int*});
+}
+
+library /*isNonNullableByDefault*/;
+import self as mix;
+import "dart:core" as core;
+
+class Mixin extends core::Object {
+  synthetic constructor •() → mix::Mixin
+    : super core::Object::•()
+    ;
+  method method(core::int? i) → core::int
+    return let final core::int? #t1 = i in #t1 == null ?{core::int} 0 : #t1{core::int};
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/main.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/main.dart.weak.modular.expect
new file mode 100644
index 0000000..ca9496c
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/main.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "test_lib.dart" as tes;
+
+import "org-dartlang-testcase:///test_lib.dart";
+
+static method main() → dynamic {
+  tes::test();
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/test_lib.dart:10:27: Error: The value 'null' can't be assigned to the parameter type 'int' because 'int' is not nullable.
+//   int j = sub.mixinMethod(null);
+//                           ^
+//
+// pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/test_lib.dart:10:15: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+//   int j = sub.mixinMethod(null);
+//               ^
+//
+// pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/test_lib.dart:12:25: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+//   sub.mixinField2 = sub.mixinField1;
+//                         ^
+//
+import self as tes;
+import "opt_out_lib.dart" as opt;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///opt_out_lib.dart";
+
+static method test() → dynamic {
+  opt::SubClass sub = new opt::SubClass::•();
+  core::int i = sub.{opt::_SubClass&Class&Mixin::classMethod}(null){(core::int*) →* core::int*};
+  core::int j = invalid-expression "pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/test_lib.dart:10:15: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+  int j = sub.mixinMethod(null);
+              ^" in sub.{opt::_SubClass&Class&Mixin::mixinMethod}(invalid-expression "pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/test_lib.dart:10:27: Error: The value 'null' can't be assigned to the parameter type 'int' because 'int' is not nullable.
+  int j = sub.mixinMethod(null);
+                          ^" in null as{TypeError,ForNonNullableByDefault} core::int){(core::int) →* core::int?} as{TypeError,ForNonNullableByDefault} core::int;
+  sub.{opt::_SubClass&Class&Mixin::classField2} = sub.{opt::_SubClass&Class&Mixin::classField1}{core::int*};
+  sub.{opt::_SubClass&Class&Mixin::mixinField2} = invalid-expression "pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/test_lib.dart:12:25: Error: A value of type 'int?' can't be assigned to a variable of type 'int' because 'int?' is nullable and 'int' isn't.
+  sub.mixinField2 = sub.mixinField1;
+                        ^" in sub.{opt::_SubClass&Class&Mixin::mixinField1}{core::int?} as{TypeError,ForNonNullableByDefault} core::int;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/main.no_link.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/main.no_link.dart.weak.modular.expect
new file mode 100644
index 0000000..5c88ecc
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in/main.no_link.dart.weak.modular.expect
@@ -0,0 +1,85 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "test_lib.dart" as tes;
+
+import "org-dartlang-testcase:///test_lib.dart";
+
+static method main() → dynamic {
+  tes::test();
+}
+
+library /*isNonNullableByDefault*/;
+import self as tes;
+import "opt_out_lib.dart" as opt;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///opt_out_lib.dart";
+
+static method test() → dynamic {
+  opt::SubClass sub = new opt::SubClass::•();
+  core::int i = sub.{opt::_SubClass&Class&Mixin::classMethod}(null){(core::int*) →* core::int*};
+  core::int j = sub.{opt::_SubClass&Class&Mixin::mixinMethod}(null){(core::int*) →* core::int*};
+  sub.{opt::_SubClass&Class&Mixin::classField2} = sub.{opt::_SubClass&Class&Mixin::classField1}{core::int*};
+  sub.{opt::_SubClass&Class&Mixin::mixinField2} = sub.{opt::_SubClass&Class&Mixin::mixinField1}{core::int*};
+}
+
+library;
+import self as opt;
+import "opt_in_lib.dart" as opt2;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///opt_in_lib.dart";
+
+abstract class _SubClass&Class&Mixin = opt2::Class with opt2::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → opt::_SubClass&Class&Mixin*
+    : super opt2::Class::•()
+    ;
+  mixin-super-stub get mixinField1() → core::int*
+    return super.{opt2::Mixin::mixinField1};
+  mixin-super-stub set mixinField1(core::int* value) → void
+    return super.{opt2::Mixin::mixinField1} = value;
+  mixin-super-stub get mixinField2() → core::int*
+    return super.{opt2::Mixin::mixinField2};
+  mixin-super-stub set mixinField2(core::int* value) → void
+    return super.{opt2::Mixin::mixinField2} = value;
+  abstract member-signature get classField1() → core::int*; -> opt2::Class::classField1
+  abstract member-signature set classField1(core::int* value) → void; -> opt2::Class::classField1
+  abstract member-signature get classField2() → core::int*; -> opt2::Class::classField2
+  abstract member-signature set classField2(core::int* value) → void; -> opt2::Class::classField2
+  mixin-super-stub method mixinMethod(core::int* i) → core::int*
+    return super.{opt2::Mixin::mixinMethod}(i);
+  abstract member-signature method classMethod(core::int* i) → core::int*; -> opt2::Class::classMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class SubClass extends opt::_SubClass&Class&Mixin {
+  synthetic constructor •() → opt::SubClass*
+    : super opt::_SubClass&Class&Mixin::•()
+    ;
+}
+
+library /*isNonNullableByDefault*/;
+import self as opt2;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int? classField1 = null;
+  field core::int classField2 = 0;
+  synthetic constructor •() → opt2::Class
+    : super core::Object::•()
+    ;
+  method classMethod(core::int i) → core::int? {}
+}
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+  field core::int? mixinField1 = null;
+  field core::int mixinField2 = 0;
+  method mixinMethod(core::int i) → core::int? {}
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in_out_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in_out_in.dart.weak.modular.expect
new file mode 100644
index 0000000..d8ff996
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_in_out_in.dart.weak.modular.expect
@@ -0,0 +1,247 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "mixin_from_opt_in_out_in_lib1.dart" as mix;
+import "mixin_from_opt_in_out_in_lib2.dart" as mix2;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///mixin_from_opt_in_out_in_lib1.dart";
+import "org-dartlang-testcase:///mixin_from_opt_in_out_in_lib2.dart";
+
+class DiB0 extends mix::C0 implements mix2::B {
+  synthetic constructor •() → self::DiB0
+    : super mix::C0::•()
+    ;
+  abstract member-signature get a() → core::List<(core::int) → core::int>; -> mix2::B::a
+  abstract member-signature set a(core::List<(core::int) → core::int> _) → void; -> mix2::B::a
+  abstract member-signature method m((core::int) → core::int x) → (core::int) → core::int; -> mix2::B::m
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+}
+class DiBq0 extends mix::C0 implements mix2::Bq {
+  synthetic constructor •() → self::DiBq0
+    : super mix::C0::•()
+    ;
+  abstract member-signature get a() → core::List<(core::int?) → core::int?>; -> mix2::B::a
+  abstract member-signature set a(core::List<(core::int?) → core::int?> _) → void; -> mix2::B::a
+  abstract member-signature method m((core::int?) → core::int? x) → (core::int?) → core::int?; -> mix2::B::m
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+}
+abstract class _DwB0&C0&B = mix::C0 with mix2::B /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_DwB0&C0&B
+    : super mix::C0::•()
+    ;
+  mixin-super-stub get a() → core::List<(core::int) → core::int>
+    return super.{mix2::B::a};
+  mixin-super-stub set a(core::List<(core::int) → core::int> _) → void
+    return super.{mix2::B::a} = _;
+  mixin-super-stub method m((core::int) → core::int x) → (core::int) → core::int
+    return super.{mix2::B::m}(x);
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+}
+class DwB0 extends self::_DwB0&C0&B {
+  synthetic constructor •() → self::DwB0
+    : super self::_DwB0&C0&B::•()
+    ;
+}
+abstract class _DwBq0&C0&Bq = mix::C0 with mix2::Bq /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_DwBq0&C0&Bq
+    : super mix::C0::•()
+    ;
+  mixin-super-stub get a() → core::List<(core::int?) → core::int?>
+    return super.{mix2::Bq::a};
+  mixin-super-stub set a(core::List<(core::int?) → core::int?> _) → void
+    return super.{mix2::Bq::a} = _;
+  mixin-super-stub method m((core::int?) → core::int? x) → (core::int?) → core::int?
+    return super.{mix2::Bq::m}(x);
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+}
+class DwBq0 extends self::_DwBq0&C0&Bq {
+  synthetic constructor •() → self::DwBq0
+    : super self::_DwBq0&C0&Bq::•()
+    ;
+}
+class DiB3 extends mix::C3 implements mix2::B {
+  synthetic constructor •() → self::DiB3
+    : super mix::C3::•()
+    ;
+  abstract member-signature get a() → core::List<(core::int) → core::int>; -> mix2::Bq::a
+  abstract member-signature set a(core::List<(core::int) → core::int> _) → void; -> mix2::Bq::a
+  abstract member-signature method m((core::int) → core::int x) → (core::int) → core::int; -> mix2::Bq::m
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+}
+class DiBq3 extends mix::C3 implements mix2::Bq {
+  synthetic constructor •() → self::DiBq3
+    : super mix::C3::•()
+    ;
+  abstract member-signature get a() → core::List<(core::int?) → core::int?>; -> mix2::Bq::a
+  abstract member-signature set a(core::List<(core::int?) → core::int?> _) → void; -> mix2::Bq::a
+  abstract member-signature method m((core::int?) → core::int? x) → (core::int?) → core::int?; -> mix2::Bq::m
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+}
+abstract class _DwB3&C3&B = mix::C3 with mix2::B /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_DwB3&C3&B
+    : super mix::C3::•()
+    ;
+  mixin-super-stub get a() → core::List<(core::int) → core::int>
+    return super.{mix2::B::a};
+  mixin-super-stub set a(core::List<(core::int) → core::int> _) → void
+    return super.{mix2::B::a} = _;
+  mixin-super-stub method m((core::int) → core::int x) → (core::int) → core::int
+    return super.{mix2::B::m}(x);
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+}
+class DwB3 extends self::_DwB3&C3&B {
+  synthetic constructor •() → self::DwB3
+    : super self::_DwB3&C3&B::•()
+    ;
+}
+abstract class _DwBq3&C3&Bq = mix::C3 with mix2::Bq /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_DwBq3&C3&Bq
+    : super mix::C3::•()
+    ;
+  mixin-super-stub get a() → core::List<(core::int?) → core::int?>
+    return super.{mix2::Bq::a};
+  mixin-super-stub set a(core::List<(core::int?) → core::int?> _) → void
+    return super.{mix2::Bq::a} = _;
+  mixin-super-stub method m((core::int?) → core::int? x) → (core::int?) → core::int?
+    return super.{mix2::Bq::m}(x);
+  abstract member-signature get _identityHashCode() → core::int; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type; -> core::Object::runtimeType
+}
+class DwBq3 extends self::_DwBq3&C3&Bq {
+  synthetic constructor •() → self::DwBq3
+    : super self::_DwBq3&C3&Bq::•()
+    ;
+}
+static method main() → dynamic {}
+
+library;
+import self as mix;
+import "mixin_from_opt_in_out_in_lib2.dart" as mix2;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///mixin_from_opt_in_out_in_lib2.dart";
+
+class C0 extends mix2::B {
+  synthetic constructor •() → mix::C0*
+    : super mix2::B::•()
+    ;
+  abstract member-signature get a() → core::List<(core::int*) →* core::int*>*; -> mix2::B::a
+  abstract member-signature set a(core::List<(core::int*) →* core::int*>* _) → void; -> mix2::B::a
+  abstract member-signature method m((core::int*) →* core::int* x) → (core::int*) →* core::int*; -> mix2::B::m
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C3 extends mix2::Bq {
+  synthetic constructor •() → mix::C3*
+    : super mix2::Bq::•()
+    ;
+  abstract member-signature get a() → core::List<(core::int*) →* core::int*>*; -> mix2::Bq::a
+  abstract member-signature set a(core::List<(core::int*) →* core::int*>* _) → void; -> mix2::Bq::a
+  abstract member-signature method m((core::int*) →* core::int* x) → (core::int*) →* core::int*; -> mix2::Bq::m
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+library /*isNonNullableByDefault*/;
+import self as mix2;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → mix2::B
+    : super core::Object::•()
+    ;
+  get a() → core::List<(core::int) → core::int>
+    return <(core::int) → core::int>[];
+  set a(core::List<(core::int) → core::int> _) → void {}
+  method m((core::int) → core::int x) → (core::int) → core::int
+    return x;
+}
+class Bq extends core::Object {
+  synthetic constructor •() → mix2::Bq
+    : super core::Object::•()
+    ;
+  get a() → core::List<(core::int?) → core::int?>
+    return <(core::int?) → core::int?>[];
+  set a(core::List<(core::int?) → core::int?> _) → void {}
+  method m((core::int?) → core::int? x) → (core::int?) → core::int?
+    return x;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..d267d60
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_out.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "mixin_from_opt_out_lib.dart" as mix;
+
+import "org-dartlang-testcase:///mixin_from_opt_out_lib.dart";
+
+abstract class _Class&Object&Mixin = core::Object with mix::Mixin /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Class&Object&Mixin
+    : super core::Object::•()
+    ;
+  mixin-super-stub method /*isLegacy*/ method(core::int* i) → core::int*
+    return super.{mix::Mixin::method}(i);
+  abstract member-signature operator /*isLegacy*/ ==(dynamic other) → core::bool*; -> core::Object::==
+}
+class Class extends self::_Class&Object&Mixin {
+  synthetic constructor •() → self::Class
+    : super self::_Class&Object&Mixin::•()
+    ;
+}
+static method main() → dynamic {
+  core::print(new self::Class::•().{self::_Class&Object&Mixin::method}(null){(core::int*) → core::int*});
+}
+
+library;
+import self as mix;
+import "dart:core" as core;
+
+class Mixin extends core::Object {
+  synthetic constructor •() → mix::Mixin*
+    : super core::Object::•()
+    ;
+  method method(core::int* i) → core::int*
+    return let final core::int* #t1 = i in #t1 == null ?{core::int*} 0 : #t1;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/mock_http_headers.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/mock_http_headers.dart.weak.modular.expect
new file mode 100644
index 0000000..740dfc6
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/mock_http_headers.dart.weak.modular.expect
@@ -0,0 +1,118 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:_http" as _ht;
+
+import "dart:io";
+
+class Mock extends core::Object {
+  synthetic constructor •() → self::Mock*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class MockHttpHeaders extends self::Mock implements _ht::HttpHeaders {
+  synthetic constructor •() → self::MockHttpHeaders*
+    : super self::Mock::•()
+    ;
+  no-such-method-forwarder get date() → core::DateTime*
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::DateTime*;
+  no-such-method-forwarder set date(core::DateTime* value) → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder get expires() → core::DateTime*
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C6, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::DateTime*;
+  no-such-method-forwarder set expires(core::DateTime* value) → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder get ifModifiedSince() → core::DateTime*
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C8, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::DateTime*;
+  no-such-method-forwarder set ifModifiedSince(core::DateTime* value) → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder get host() → core::String*
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C10, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::String*;
+  no-such-method-forwarder set host(core::String* value) → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C11, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder get port() → core::int*
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C12, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::int*;
+  no-such-method-forwarder set port(core::int* value) → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C13, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder get contentType() → _ht::ContentType*
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C14, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} _ht::ContentType*;
+  no-such-method-forwarder set contentType(_ht::ContentType* value) → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C15, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder get contentLength() → core::int*
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C16, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::int*;
+  no-such-method-forwarder set contentLength(core::int* value) → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C17, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder get persistentConnection() → core::bool*
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C18, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::bool*;
+  no-such-method-forwarder set persistentConnection(core::bool* value) → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C19, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder get chunkedTransferEncoding() → core::bool*
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C20, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::bool*;
+  no-such-method-forwarder set chunkedTransferEncoding(core::bool* value) → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C21, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder operator [](core::String* name) → core::List<core::String*>*
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C22, 0, #C2, core::List::unmodifiable<dynamic>(<dynamic>[name]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::List<core::String*>*;
+  no-such-method-forwarder method value(core::String* name) → core::String*
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C23, 0, #C2, core::List::unmodifiable<dynamic>(<dynamic>[name]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::String*;
+  no-such-method-forwarder method add(core::String* name, core::Object* value, {core::bool* preserveHeaderCase = #C24}) → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C25, 0, #C2, core::List::unmodifiable<dynamic>(<dynamic>[name, value]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C26: preserveHeaderCase}))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method set(core::String* name, core::Object* value, {core::bool* preserveHeaderCase = #C24}) → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C27, 0, #C2, core::List::unmodifiable<dynamic>(<dynamic>[name, value]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C26: preserveHeaderCase}))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method remove(core::String* name, core::Object* value) → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C28, 0, #C2, core::List::unmodifiable<dynamic>(<dynamic>[name, value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method removeAll(core::String* name) → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C29, 0, #C2, core::List::unmodifiable<dynamic>(<dynamic>[name]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method forEach((core::String*, core::List<core::String*>*) →* void action) → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C30, 0, #C2, core::List::unmodifiable<dynamic>(<dynamic>[action]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method noFolding(core::String* name) → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C31, 0, #C2, core::List::unmodifiable<dynamic>(<dynamic>[name]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder method /* from org-dartlang-sdk:///sdk/lib/_http/http.dart */ clear() → void
+    return this.{self::Mock::noSuchMethod}(new core::_InvocationMirror::_withType(#C32, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #date
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+  #C5 = #date=
+  #C6 = #expires
+  #C7 = #expires=
+  #C8 = #ifModifiedSince
+  #C9 = #ifModifiedSince=
+  #C10 = #host
+  #C11 = #host=
+  #C12 = #port
+  #C13 = #port=
+  #C14 = #contentType
+  #C15 = #contentType=
+  #C16 = #contentLength
+  #C17 = #contentLength=
+  #C18 = #persistentConnection
+  #C19 = #persistentConnection=
+  #C20 = #chunkedTransferEncoding
+  #C21 = #chunkedTransferEncoding=
+  #C22 = #[]
+  #C23 = #value
+  #C24 = false
+  #C25 = #add
+  #C26 = #preserveHeaderCase
+  #C27 = #set
+  #C28 = #remove
+  #C29 = #removeAll
+  #C30 = #forEach
+  #C31 = #noFolding
+  #C32 = #clear
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/never_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/never_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..3a15eee
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/never_opt_out.dart.weak.modular.expect
@@ -0,0 +1,187 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "never_opt_out_lib.dart" as nev;
+
+import "org-dartlang-testcase:///never_opt_out_lib.dart";
+
+class GenericClass<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::GenericClass<self::GenericClass::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends nev::A {
+  field Null neverField = null;
+  field Null nullField = null;
+  synthetic constructor •() → self::B*
+    : super nev::A::•()
+    ;
+  method neverMethod(Null value) → Null
+    return value;
+  get neverProperty() → Null
+    return null;
+  set neverProperty(Null value) → void {}
+  method nullMethod(Null value) → Null
+    return value;
+  get nullProperty() → Null
+    return null;
+  set nullProperty(Null value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends nev::A {
+  field Never* neverField = null;
+  field Never* nullField = null;
+  synthetic constructor •() → self::C*
+    : super nev::A::•()
+    ;
+  method neverMethod(Null value) → Never*
+    return value;
+  get neverProperty() → Never*
+    return null;
+  set neverProperty(Null value) → void {}
+  method nullMethod(Null value) → Never*
+    return value;
+  get nullProperty() → Never*
+    return null;
+  set nullProperty(Null value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field Never* optOutNever;
+static field dynamic inferredOptOutNever = nev::optInNever;
+static method genericMethod<T extends core::Object* = dynamic>() → dynamic {}
+static method main() → dynamic {
+  nev::optInNever = self::optOutNever;
+  core::Type* typeNever = #C1;
+  self::genericMethod<Never*>();
+  new self::GenericClass::•<Never*>();
+  Never* localNever = null;
+  Null localNull = null;
+  dynamic inferredLocalNever = nev::optInNever;
+  localNever = localNever;
+  self::optOutNever = localNever;
+  nev::optInNever = localNever;
+  localNull = localNever;
+  self::inferredOptOutNever = localNever;
+  inferredLocalNever = localNever;
+  localNever = self::optOutNever;
+  self::optOutNever = self::optOutNever;
+  nev::optInNever = self::optOutNever;
+  localNull = self::optOutNever;
+  self::inferredOptOutNever = self::optOutNever;
+  inferredLocalNever = self::optOutNever;
+  localNever = nev::optInNever;
+  self::optOutNever = nev::optInNever;
+  nev::optInNever = nev::optInNever;
+  localNull = nev::optInNever;
+  self::inferredOptOutNever = nev::optInNever;
+  inferredLocalNever = nev::optInNever;
+  localNever = localNull;
+  self::optOutNever = localNull;
+  nev::optInNever = localNull;
+  localNull = localNull;
+  self::inferredOptOutNever = localNull;
+  inferredLocalNever = localNull;
+  localNever = self::inferredOptOutNever as{TypeError,ForDynamic} Never*;
+  self::optOutNever = self::inferredOptOutNever as{TypeError,ForDynamic} Never*;
+  nev::optInNever = self::inferredOptOutNever as{TypeError,ForDynamic} Never;
+  localNull = self::inferredOptOutNever as{TypeError,ForDynamic} Null;
+  self::inferredOptOutNever = self::inferredOptOutNever;
+  inferredLocalNever = self::inferredOptOutNever;
+  localNever = inferredLocalNever as{TypeError,ForDynamic} Never*;
+  self::optOutNever = inferredLocalNever as{TypeError,ForDynamic} Never*;
+  nev::optInNever = inferredLocalNever as{TypeError,ForDynamic} Never;
+  localNull = inferredLocalNever as{TypeError,ForDynamic} Null;
+  self::inferredOptOutNever = inferredLocalNever;
+  inferredLocalNever = inferredLocalNever;
+  self::throws(() → Null => self::optOutNever = nev::throwing());
+  self::throws(() → Null => localNever = nev::throwing());
+  self::throws(() → Null => self::optOutNever = nev::throwing());
+  self::throws(() → Null => nev::optInNever = nev::throwing());
+  self::throws(() → Null => self::inferredOptOutNever = nev::throwing());
+  self::throws(() → Null => inferredLocalNever = nev::throwing());
+  nev::BoundedGenericClass<Null>* boundedGenericClass = new nev::BoundedGenericClass::•<Null>();
+  self::throws(() → Null {
+    dynamic boundedGenericMethodResult1 = nev::boundedGenericMethod1<Null>();
+  });
+  core::List<Null>* boundedGenericMethodResult2 = nev::boundedGenericMethod2<Null>();
+  dynamic dyn = null;
+  nev::optInNever = dyn as{TypeError,ForDynamic} Never;
+}
+static method throws(() →* void f) → dynamic {
+  try {
+    f(){() →* void};
+  }
+  on dynamic catch(final dynamic _) {
+    return;
+  }
+  throw "Expected exception";
+}
+
+library /*isNonNullableByDefault*/;
+import self as nev;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+import "org-dartlang-testcase:///never_opt_out.dart";
+
+class A extends core::Object {
+  field Never neverField = throw "Should not reach here";
+  field Null nullField = null;
+  synthetic constructor •() → nev::A
+    : super core::Object::•()
+    ;
+  method neverMethod(Never value) → Never
+    return let final Never #t1 = value in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  get neverProperty() → Never
+    return throw "Should not reach here";
+  set neverProperty(Never value) → void {}
+  method nullMethod(Null value) → Null
+    return value;
+  get nullProperty() → Null
+    return null;
+  set nullProperty(Null value) → void {}
+}
+class BoundedGenericClass<T extends Never> extends core::Object {
+  synthetic constructor •() → nev::BoundedGenericClass<nev::BoundedGenericClass::T>
+    : super core::Object::•()
+    ;
+}
+late static field Never optInNever;
+static method throwing() → Never
+  return throw "Never!";
+static method boundedGenericMethod1<T extends Never>() → nev::boundedGenericMethod1::T
+  return throw "Should never return";
+static method boundedGenericMethod2<T extends Never>() → core::List<nev::boundedGenericMethod2::T>
+  return <nev::boundedGenericMethod2::T>[];
+
+constants  {
+  #C1 = TypeLiteralConstant(Never*)
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/nnbd_opt_out_language_version.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/nnbd_opt_out_language_version.dart.weak.modular.expect
new file mode 100644
index 0000000..f6eb3c3
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/nnbd_opt_out_language_version.dart.weak.modular.expect
@@ -0,0 +1,61 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class late extends core::Object {
+  synthetic constructor •() → self::late*
+    : super core::Object::•()
+    ;
+  get g() → core::int*
+    return 1;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class required extends core::Object {
+  synthetic constructor •() → self::required*
+    : super core::Object::•()
+    ;
+  get g() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  field self::late* l = new self::late::•();
+  field self::required* r = new self::required::•();
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  if(!(new self::C::•().{self::C::l}{self::late*}.{self::late::g}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} 1))
+    throw "Expected 1";
+  if(!(new self::C::•().{self::C::r}{self::required*}.{self::required::g}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} 2))
+    throw "Expected 2";
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/nnbd_opt_out_language_version_try_to_trick.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/nnbd_opt_out_language_version_try_to_trick.dart.weak.modular.expect
new file mode 100644
index 0000000..f6eb3c3
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/nnbd_opt_out_language_version_try_to_trick.dart.weak.modular.expect
@@ -0,0 +1,61 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class late extends core::Object {
+  synthetic constructor •() → self::late*
+    : super core::Object::•()
+    ;
+  get g() → core::int*
+    return 1;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class required extends core::Object {
+  synthetic constructor •() → self::required*
+    : super core::Object::•()
+    ;
+  get g() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  field self::late* l = new self::late::•();
+  field self::required* r = new self::required::•();
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  if(!(new self::C::•().{self::C::l}{self::late*}.{self::late::g}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} 1))
+    throw "Expected 1";
+  if(!(new self::C::•().{self::C::r}{self::required*}.{self::required::g}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} 2))
+    throw "Expected 2";
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/no_null_shorting.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/no_null_shorting.dart.weak.modular.expect
new file mode 100644
index 0000000..9e9eb03
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/no_null_shorting.dart.weak.modular.expect
@@ -0,0 +1,161 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field self::Class* field = null;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  method method() → self::Class*
+    return this.{self::Class::field}{self::Class*};
+  operator [](self::Class* key) → self::Class*
+    return this.{self::Class::field}{self::Class*};
+  operator []=(self::Class* key, self::Class* value) → void {
+    this.{self::Class::field} = value;
+  }
+  operator +(core::int* value) → self::Class*
+    return this.{self::Class::field}{self::Class*};
+  operator unary-() → self::Class*
+    return this.{self::Class::field}{self::Class*};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::propertyAccess(null);
+  self::indexAccess(null);
+  self::operatorAccess(null);
+  self::ifNull(null);
+}
+static method propertyAccess(self::Class* c) → void {
+  let final self::Class* #t1 = c in #t1 == null ?{self::Class*} null : #t1.{self::Class::field}{self::Class*};
+  let final self::Class* #t2 = c in #t2 == null ?{self::Class*} null : #t2.{self::Class::field} = new self::Class::•();
+  c = let final self::Class* #t3 = c in #t3 == null ?{self::Class*} null : #t3.{self::Class::field} = new self::Class::•();
+  let final self::Class* #t4 = c in #t4 == null ?{self::Class*} null : #t4.{self::Class::method}(){() →* self::Class*};
+  self::throws(() → self::Class* => (let final self::Class* #t5 = c in #t5 == null ?{self::Class*} null : #t5.{self::Class::field}{self::Class*}).{self::Class::field}{self::Class*});
+  let final self::Class* #t6 = let final self::Class* #t7 = c in #t7 == null ?{self::Class*} null : #t7.{self::Class::field}{self::Class*} in #t6 == null ?{self::Class*} null : #t6.{self::Class::field}{self::Class*};
+  self::throws(() → self::Class* => let final self::Class* #t8 = (let final self::Class* #t9 = c in #t9 == null ?{self::Class*} null : #t9.{self::Class::field}{self::Class*}).{self::Class::field}{self::Class*} in #t8 == null ?{self::Class*} null : #t8.{self::Class::field}{self::Class*});
+  self::throws(() → self::Class* => (let final self::Class* #t10 = c in #t10 == null ?{self::Class*} null : #t10.{self::Class::field}{self::Class*}).{self::Class::field} = new self::Class::•());
+  let final self::Class* #t11 = let final self::Class* #t12 = c in #t12 == null ?{self::Class*} null : #t12.{self::Class::field}{self::Class*} in #t11 == null ?{self::Class*} null : #t11.{self::Class::field} = new self::Class::•();
+  self::throws(() → self::Class* => let final self::Class* #t13 = (let final self::Class* #t14 = c in #t14 == null ?{self::Class*} null : #t14.{self::Class::field}{self::Class*}).{self::Class::field}{self::Class*} in #t13 == null ?{self::Class*} null : #t13.{self::Class::field} = new self::Class::•());
+  self::throws(() → self::Class* => (let final self::Class* #t15 = c in #t15 == null ?{self::Class*} null : #t15.{self::Class::field}{self::Class*}).{self::Class::field}{self::Class*});
+  self::throws(() → self::Class* => (let final self::Class* #t16 = c in #t16 == null ?{self::Class*} null : #t16.{self::Class::field} = new self::Class::•()).{self::Class::field}{self::Class*});
+  self::throws(() → self::Class* => (let final self::Class* #t17 = c in #t17 == null ?{self::Class*} null : #t17.{self::Class::method}(){() →* self::Class*}).{self::Class::field}{self::Class*});
+  self::throws(() → self::Class* => c = (let final self::Class* #t18 = c in #t18 == null ?{self::Class*} null : #t18.{self::Class::field}{self::Class*}).{self::Class::field} = new self::Class::•());
+  c = let final self::Class* #t19 = let final self::Class* #t20 = c in #t20 == null ?{self::Class*} null : #t20.{self::Class::field}{self::Class*} in #t19 == null ?{self::Class*} null : #t19.{self::Class::field} = new self::Class::•();
+  self::throws(() → self::Class* => c = let final self::Class* #t21 = (let final self::Class* #t22 = c in #t22 == null ?{self::Class*} null : #t22.{self::Class::field}{self::Class*}).{self::Class::field}{self::Class*} in #t21 == null ?{self::Class*} null : #t21.{self::Class::field} = new self::Class::•());
+  self::throws(() → self::Class* => (let final self::Class* #t23 = c in #t23 == null ?{self::Class*} null : #t23.{self::Class::field}{self::Class*}).{self::Class::method}(){() →* self::Class*});
+  let final self::Class* #t24 = c in #t24 == null ?{self::Class*} null : #t24.{self::Class::field} = new self::Class::•().{self::Class::field}{self::Class*};
+  c = let final self::Class* #t25 = c in #t25 == null ?{self::Class*} null : #t25.{self::Class::field} = new self::Class::•().{self::Class::field}{self::Class*};
+  let final self::Class* #t26 = c in #t26 == null ?{self::Class*} null : #t26.{self::Class::field} = new self::Class::•().{self::Class::field} = new self::Class::•();
+  c = let final self::Class* #t27 = c in #t27 == null ?{self::Class*} null : #t27.{self::Class::field} = new self::Class::•().{self::Class::field} = new self::Class::•();
+  let final self::Class* #t28 = c in #t28 == null ?{self::Class*} null : #t28.{self::Class::field} = new self::Class::•().{self::Class::method}(){() →* self::Class*};
+  c = let final self::Class* #t29 = c in #t29 == null ?{self::Class*} null : #t29.{self::Class::field} = new self::Class::•().{self::Class::method}(){() →* self::Class*};
+  self::throws(() → self::Class* => (let final self::Class* #t30 = c in #t30 == null ?{self::Class*} null : #t30.{self::Class::method}(){() →* self::Class*}).{self::Class::field}{self::Class*});
+  self::throws(() → self::Class* => (let final self::Class* #t31 = c in #t31 == null ?{self::Class*} null : #t31.{self::Class::method}(){() →* self::Class*}).{self::Class::field} = new self::Class::•());
+  self::throws(() → self::Class* => (let final self::Class* #t32 = c in #t32 == null ?{self::Class*} null : #t32.{self::Class::method}(){() →* self::Class*}).{self::Class::method}(){() →* self::Class*});
+  self::throws(() → self::Class* => (let final self::Class* #t33 = c in #t33 == null ?{self::Class*} null : #t33.{self::Class::field}{self::Class*}).{self::Class::field}{self::Class*}.{self::Class::field}{self::Class*});
+  self::throws(() → self::Class* => (let final self::Class* #t34 = c in #t34 == null ?{self::Class*} null : #t34.{self::Class::field}{self::Class*}).{self::Class::field}{self::Class*}.{self::Class::field} = new self::Class::•());
+  self::throws(() → self::Class* => c = (let final self::Class* #t35 = c in #t35 == null ?{self::Class*} null : #t35.{self::Class::field}{self::Class*}).{self::Class::field}{self::Class*}.{self::Class::field} = new self::Class::•());
+  self::throws(() → self::Class* => (let final self::Class* #t36 = c in #t36 == null ?{self::Class*} null : #t36.{self::Class::field}{self::Class*}).{self::Class::field}{self::Class*}.{self::Class::method}(){() →* self::Class*});
+  let final self::Class* #t37 = c in #t37 == null ?{self::Class*} null : #t37.{self::Class::field} = new self::Class::•().{self::Class::field}{self::Class*}.{self::Class::field}{self::Class*};
+  c = let final self::Class* #t38 = c in #t38 == null ?{self::Class*} null : #t38.{self::Class::field} = new self::Class::•().{self::Class::field}{self::Class*}.{self::Class::field}{self::Class*};
+  let final self::Class* #t39 = c in #t39 == null ?{self::Class*} null : #t39.{self::Class::field} = new self::Class::•().{self::Class::field}{self::Class*}.{self::Class::field} = new self::Class::•();
+  c = let final self::Class* #t40 = c in #t40 == null ?{self::Class*} null : #t40.{self::Class::field} = new self::Class::•().{self::Class::field}{self::Class*}.{self::Class::field} = new self::Class::•();
+  let final self::Class* #t41 = c in #t41 == null ?{self::Class*} null : #t41.{self::Class::field} = new self::Class::•().{self::Class::field}{self::Class*}.{self::Class::method}(){() →* self::Class*};
+  c = let final self::Class* #t42 = c in #t42 == null ?{self::Class*} null : #t42.{self::Class::field} = new self::Class::•().{self::Class::field}{self::Class*}.{self::Class::method}(){() →* self::Class*};
+  self::throws(() → self::Class* => (let final self::Class* #t43 = c in #t43 == null ?{self::Class*} null : #t43.{self::Class::method}(){() →* self::Class*}).{self::Class::field}{self::Class*}.{self::Class::field}{self::Class*});
+  self::throws(() → self::Class* => (let final self::Class* #t44 = c in #t44 == null ?{self::Class*} null : #t44.{self::Class::method}(){() →* self::Class*}).{self::Class::field}{self::Class*}.{self::Class::field} = new self::Class::•());
+  self::throws(() → self::Class* => (let final self::Class* #t45 = c in #t45 == null ?{self::Class*} null : #t45.{self::Class::method}(){() →* self::Class*}).{self::Class::field}{self::Class*}.{self::Class::method}(){() →* self::Class*});
+  self::throws(() → self::Class* => (let final self::Class* #t46 = c in #t46 == null ?{self::Class*} null : #t46.{self::Class::field}{self::Class*}).{self::Class::field} = new self::Class::•().{self::Class::field}{self::Class*});
+  self::throws(() → self::Class* => c = (let final self::Class* #t47 = c in #t47 == null ?{self::Class*} null : #t47.{self::Class::field}{self::Class*}).{self::Class::field} = new self::Class::•().{self::Class::field}{self::Class*});
+  self::throws(() → self::Class* => (let final self::Class* #t48 = c in #t48 == null ?{self::Class*} null : #t48.{self::Class::field}{self::Class*}).{self::Class::field} = new self::Class::•().{self::Class::field} = new self::Class::•());
+  self::throws(() → self::Class* => c = (let final self::Class* #t49 = c in #t49 == null ?{self::Class*} null : #t49.{self::Class::field}{self::Class*}).{self::Class::field} = new self::Class::•().{self::Class::field} = new self::Class::•());
+  self::throws(() → self::Class* => (let final self::Class* #t50 = c in #t50 == null ?{self::Class*} null : #t50.{self::Class::field}{self::Class*}).{self::Class::field} = new self::Class::•().{self::Class::method}(){() →* self::Class*});
+  self::throws(() → self::Class* => c = (let final self::Class* #t51 = c in #t51 == null ?{self::Class*} null : #t51.{self::Class::field}{self::Class*}).{self::Class::field} = new self::Class::•().{self::Class::method}(){() →* self::Class*});
+  let final self::Class* #t52 = c in #t52 == null ?{self::Class*} null : #t52.{self::Class::field} = new self::Class::•().{self::Class::field} = new self::Class::•().{self::Class::field}{self::Class*};
+  c = let final self::Class* #t53 = c in #t53 == null ?{self::Class*} null : #t53.{self::Class::field} = new self::Class::•().{self::Class::field} = new self::Class::•().{self::Class::field}{self::Class*};
+  let final self::Class* #t54 = c in #t54 == null ?{self::Class*} null : #t54.{self::Class::field} = new self::Class::•().{self::Class::field} = new self::Class::•().{self::Class::field} = new self::Class::•();
+  c = let final self::Class* #t55 = c in #t55 == null ?{self::Class*} null : #t55.{self::Class::field} = new self::Class::•().{self::Class::field} = new self::Class::•().{self::Class::field} = new self::Class::•();
+  let final self::Class* #t56 = c in #t56 == null ?{self::Class*} null : #t56.{self::Class::field} = new self::Class::•().{self::Class::field} = new self::Class::•().{self::Class::method}(){() →* self::Class*};
+  c = let final self::Class* #t57 = c in #t57 == null ?{self::Class*} null : #t57.{self::Class::field} = new self::Class::•().{self::Class::field} = new self::Class::•().{self::Class::method}(){() →* self::Class*};
+  self::throws(() → self::Class* => (let final self::Class* #t58 = c in #t58 == null ?{self::Class*} null : #t58.{self::Class::method}(){() →* self::Class*}).{self::Class::field} = new self::Class::•().{self::Class::field}{self::Class*});
+  self::throws(() → self::Class* => c = (let final self::Class* #t59 = c in #t59 == null ?{self::Class*} null : #t59.{self::Class::method}(){() →* self::Class*}).{self::Class::field} = new self::Class::•().{self::Class::field}{self::Class*});
+  self::throws(() → self::Class* => (let final self::Class* #t60 = c in #t60 == null ?{self::Class*} null : #t60.{self::Class::method}(){() →* self::Class*}).{self::Class::field} = new self::Class::•().{self::Class::field} = new self::Class::•());
+  self::throws(() → self::Class* => c = (let final self::Class* #t61 = c in #t61 == null ?{self::Class*} null : #t61.{self::Class::method}(){() →* self::Class*}).{self::Class::field} = new self::Class::•().{self::Class::field} = new self::Class::•());
+  self::throws(() → self::Class* => (let final self::Class* #t62 = c in #t62 == null ?{self::Class*} null : #t62.{self::Class::method}(){() →* self::Class*}).{self::Class::field} = new self::Class::•().{self::Class::method}(){() →* self::Class*});
+  self::throws(() → self::Class* => c = (let final self::Class* #t63 = c in #t63 == null ?{self::Class*} null : #t63.{self::Class::method}(){() →* self::Class*}).{self::Class::field} = new self::Class::•().{self::Class::method}(){() →* self::Class*});
+  self::throws(() → self::Class* => (let final self::Class* #t64 = c in #t64 == null ?{self::Class*} null : #t64.{self::Class::field}{self::Class*}).{self::Class::method}(){() →* self::Class*}.{self::Class::field}{self::Class*});
+  self::throws(() → self::Class* => (let final self::Class* #t65 = c in #t65 == null ?{self::Class*} null : #t65.{self::Class::field}{self::Class*}).{self::Class::method}(){() →* self::Class*}.{self::Class::field} = new self::Class::•());
+  self::throws(() → self::Class* => c = (let final self::Class* #t66 = c in #t66 == null ?{self::Class*} null : #t66.{self::Class::field}{self::Class*}).{self::Class::method}(){() →* self::Class*}.{self::Class::field} = new self::Class::•());
+  self::throws(() → self::Class* => (let final self::Class* #t67 = c in #t67 == null ?{self::Class*} null : #t67.{self::Class::field}{self::Class*}).{self::Class::method}(){() →* self::Class*}.{self::Class::method}(){() →* self::Class*});
+  let final self::Class* #t68 = c in #t68 == null ?{self::Class*} null : #t68.{self::Class::field} = new self::Class::•().{self::Class::method}(){() →* self::Class*}.{self::Class::field}{self::Class*};
+  c = let final self::Class* #t69 = c in #t69 == null ?{self::Class*} null : #t69.{self::Class::field} = new self::Class::•().{self::Class::method}(){() →* self::Class*}.{self::Class::field}{self::Class*};
+  let final self::Class* #t70 = c in #t70 == null ?{self::Class*} null : #t70.{self::Class::field} = new self::Class::•().{self::Class::method}(){() →* self::Class*}.{self::Class::field} = new self::Class::•();
+  c = let final self::Class* #t71 = c in #t71 == null ?{self::Class*} null : #t71.{self::Class::field} = new self::Class::•().{self::Class::method}(){() →* self::Class*}.{self::Class::field} = new self::Class::•();
+  let final self::Class* #t72 = c in #t72 == null ?{self::Class*} null : #t72.{self::Class::field} = new self::Class::•().{self::Class::method}(){() →* self::Class*}.{self::Class::method}(){() →* self::Class*};
+  c = let final self::Class* #t73 = c in #t73 == null ?{self::Class*} null : #t73.{self::Class::field} = new self::Class::•().{self::Class::method}(){() →* self::Class*}.{self::Class::method}(){() →* self::Class*};
+  self::throws(() → self::Class* => (let final self::Class* #t74 = c in #t74 == null ?{self::Class*} null : #t74.{self::Class::method}(){() →* self::Class*}).{self::Class::method}(){() →* self::Class*}.{self::Class::field}{self::Class*});
+  self::throws(() → self::Class* => (let final self::Class* #t75 = c in #t75 == null ?{self::Class*} null : #t75.{self::Class::method}(){() →* self::Class*}).{self::Class::method}(){() →* self::Class*}.{self::Class::field} = new self::Class::•());
+  self::throws(() → self::Class* => (let final self::Class* #t76 = c in #t76 == null ?{self::Class*} null : #t76.{self::Class::method}(){() →* self::Class*}).{self::Class::method}(){() →* self::Class*}.{self::Class::method}(){() →* self::Class*});
+  let final self::Class* #t77 = let final self::Class* #t78 = c in #t78 == null ?{self::Class*} null : #t78.{self::Class::method}(){() →* self::Class*} in #t77 == null ?{self::Class*} null : #t77.{self::Class::method}(){() →* self::Class*};
+}
+static method indexAccess(self::Class* c) → void {
+  self::throws(() → self::Class* => (let final self::Class* #t79 = c in #t79 == null ?{self::Class*} null : #t79.{self::Class::field}{self::Class*}).{self::Class::[]}(c){(self::Class*) →* self::Class*});
+  self::throws(() → self::Class* => let final self::Class* #t80 = let final self::Class* #t81 = c in #t81 == null ?{self::Class*} null : #t81.{self::Class::field}{self::Class*} in let final self::Class* #t82 = c in let final self::Class* #t83 = new self::Class::•() in let final void #t84 = #t80.{self::Class::[]=}(#t82, #t83){(self::Class*, self::Class*) →* void} in #t83);
+  self::throws(() → self::Class* => c = let final self::Class* #t85 = let final self::Class* #t86 = c in #t86 == null ?{self::Class*} null : #t86.{self::Class::field}{self::Class*} in let final self::Class* #t87 = c in let final self::Class* #t88 = new self::Class::•() in let final void #t89 = #t85.{self::Class::[]=}(#t87, #t88){(self::Class*, self::Class*) →* void} in #t88);
+  self::throws(() → self::Class* => (let final self::Class* #t90 = c in #t90 == null ?{self::Class*} null : #t90.{self::Class::field}{self::Class*}).{self::Class::[]}(c){(self::Class*) →* self::Class*}.{self::Class::method}(){() →* self::Class*});
+  self::throws(() → self::Class* => let final self::Class* #t91 = let final self::Class* #t92 = c in #t92 == null ?{self::Class*} null : #t92.{self::Class::field}{self::Class*} in let final self::Class* #t93 = c in let final self::Class* #t94 = #t91.{self::Class::[]}(#t93){(self::Class*) →* self::Class*}.{self::Class::+}(0){(core::int*) →* self::Class*} in let final void #t95 = #t91.{self::Class::[]=}(#t93, #t94){(self::Class*, self::Class*) →* void} in #t94);
+  self::throws(() → self::Class* => c = let final self::Class* #t96 = let final self::Class* #t97 = c in #t97 == null ?{self::Class*} null : #t97.{self::Class::field}{self::Class*} in let final self::Class* #t98 = c in let final self::Class* #t99 = #t96.{self::Class::[]}(#t98){(self::Class*) →* self::Class*}.{self::Class::+}(0){(core::int*) →* self::Class*} in let final void #t100 = #t96.{self::Class::[]=}(#t98, #t99){(self::Class*, self::Class*) →* void} in #t99);
+  self::throws(() → self::Class* => let final self::Class* #t101 = let final self::Class* #t102 = c in #t102 == null ?{self::Class*} null : #t102.{self::Class::field}{self::Class*} in let final self::Class* #t103 = c in let final self::Class* #t104 = #t101.{self::Class::[]}(#t103){(self::Class*) →* self::Class*} in let final void #t105 = #t101.{self::Class::[]=}(#t103, #t104.{self::Class::+}(1){(core::int*) →* self::Class*}){(self::Class*, self::Class*) →* void} in #t104);
+  self::throws(() → self::Class* => c = let final self::Class* #t106 = let final self::Class* #t107 = c in #t107 == null ?{self::Class*} null : #t107.{self::Class::field}{self::Class*} in let final self::Class* #t108 = c in let final self::Class* #t109 = #t106.{self::Class::[]}(#t108){(self::Class*) →* self::Class*} in let final void #t110 = #t106.{self::Class::[]=}(#t108, #t109.{self::Class::+}(1){(core::int*) →* self::Class*}){(self::Class*, self::Class*) →* void} in #t109);
+  self::throws(() → self::Class* => let final self::Class* #t111 = let final self::Class* #t112 = c in #t112 == null ?{self::Class*} null : #t112.{self::Class::field}{self::Class*} in let final self::Class* #t113 = c in let final self::Class* #t114 = #t111.{self::Class::[]}(#t113){(self::Class*) →* self::Class*}.{self::Class::+}(1){(core::int*) →* self::Class*} in let final void #t115 = #t111.{self::Class::[]=}(#t113, #t114){(self::Class*, self::Class*) →* void} in #t114);
+  self::throws(() → self::Class* => c = let final self::Class* #t116 = let final self::Class* #t117 = c in #t117 == null ?{self::Class*} null : #t117.{self::Class::field}{self::Class*} in let final self::Class* #t118 = c in let final self::Class* #t119 = #t116.{self::Class::[]}(#t118){(self::Class*) →* self::Class*}.{self::Class::+}(1){(core::int*) →* self::Class*} in let final void #t120 = #t116.{self::Class::[]=}(#t118, #t119){(self::Class*, self::Class*) →* void} in #t119);
+  self::throws(() → self::Class* => (let final self::Class* #t121 = c in #t121 == null ?{self::Class*} null : #t121.{self::Class::field}{self::Class*}).{self::Class::[]}(c){(self::Class*) →* self::Class*}.{self::Class::[]}(c){(self::Class*) →* self::Class*});
+  self::throws(() → self::Class* => let final self::Class* #t122 = (let final self::Class* #t123 = c in #t123 == null ?{self::Class*} null : #t123.{self::Class::field}{self::Class*}).{self::Class::[]}(c){(self::Class*) →* self::Class*} in let final self::Class* #t124 = c in let final self::Class* #t125 = new self::Class::•() in let final void #t126 = #t122.{self::Class::[]=}(#t124, #t125){(self::Class*, self::Class*) →* void} in #t125);
+  self::throws(() → self::Class* => c = let final self::Class* #t127 = (let final self::Class* #t128 = c in #t128 == null ?{self::Class*} null : #t128.{self::Class::field}{self::Class*}).{self::Class::[]}(c){(self::Class*) →* self::Class*} in let final self::Class* #t129 = c in let final self::Class* #t130 = new self::Class::•() in let final void #t131 = #t127.{self::Class::[]=}(#t129, #t130){(self::Class*, self::Class*) →* void} in #t130);
+  self::throws(() → self::Class* => (let final self::Class* #t132 = c in #t132 == null ?{self::Class*} null : #t132.{self::Class::field}{self::Class*}).{self::Class::[]}(c){(self::Class*) →* self::Class*}.{self::Class::[]}(c){(self::Class*) →* self::Class*}.{self::Class::method}(){() →* self::Class*});
+  self::throws(() → self::Class* => let final self::Class* #t133 = (let final self::Class* #t134 = c in #t134 == null ?{self::Class*} null : #t134.{self::Class::field}{self::Class*}).{self::Class::[]}(c){(self::Class*) →* self::Class*} in let final self::Class* #t135 = c in let final self::Class* #t136 = #t133.{self::Class::[]}(#t135){(self::Class*) →* self::Class*}.{self::Class::+}(0){(core::int*) →* self::Class*} in let final void #t137 = #t133.{self::Class::[]=}(#t135, #t136){(self::Class*, self::Class*) →* void} in #t136);
+  self::throws(() → self::Class* => c = let final self::Class* #t138 = (let final self::Class* #t139 = c in #t139 == null ?{self::Class*} null : #t139.{self::Class::field}{self::Class*}).{self::Class::[]}(c){(self::Class*) →* self::Class*} in let final self::Class* #t140 = c in let final self::Class* #t141 = #t138.{self::Class::[]}(#t140){(self::Class*) →* self::Class*}.{self::Class::+}(0){(core::int*) →* self::Class*} in let final void #t142 = #t138.{self::Class::[]=}(#t140, #t141){(self::Class*, self::Class*) →* void} in #t141);
+  self::throws(() → self::Class* => let final self::Class* #t143 = (let final self::Class* #t144 = c in #t144 == null ?{self::Class*} null : #t144.{self::Class::field}{self::Class*}).{self::Class::[]}(c){(self::Class*) →* self::Class*} in let final self::Class* #t145 = c in let final self::Class* #t146 = #t143.{self::Class::[]}(#t145){(self::Class*) →* self::Class*} in let final void #t147 = #t143.{self::Class::[]=}(#t145, #t146.{self::Class::+}(1){(core::int*) →* self::Class*}){(self::Class*, self::Class*) →* void} in #t146);
+  self::throws(() → self::Class* => c = let final self::Class* #t148 = (let final self::Class* #t149 = c in #t149 == null ?{self::Class*} null : #t149.{self::Class::field}{self::Class*}).{self::Class::[]}(c){(self::Class*) →* self::Class*} in let final self::Class* #t150 = c in let final self::Class* #t151 = #t148.{self::Class::[]}(#t150){(self::Class*) →* self::Class*} in let final void #t152 = #t148.{self::Class::[]=}(#t150, #t151.{self::Class::+}(1){(core::int*) →* self::Class*}){(self::Class*, self::Class*) →* void} in #t151);
+  self::throws(() → self::Class* => let final self::Class* #t153 = (let final self::Class* #t154 = c in #t154 == null ?{self::Class*} null : #t154.{self::Class::field}{self::Class*}).{self::Class::[]}(c){(self::Class*) →* self::Class*} in let final self::Class* #t155 = c in let final self::Class* #t156 = #t153.{self::Class::[]}(#t155){(self::Class*) →* self::Class*}.{self::Class::+}(1){(core::int*) →* self::Class*} in let final void #t157 = #t153.{self::Class::[]=}(#t155, #t156){(self::Class*, self::Class*) →* void} in #t156);
+  self::throws(() → self::Class* => c = let final self::Class* #t158 = (let final self::Class* #t159 = c in #t159 == null ?{self::Class*} null : #t159.{self::Class::field}{self::Class*}).{self::Class::[]}(c){(self::Class*) →* self::Class*} in let final self::Class* #t160 = c in let final self::Class* #t161 = #t158.{self::Class::[]}(#t160){(self::Class*) →* self::Class*}.{self::Class::+}(1){(core::int*) →* self::Class*} in let final void #t162 = #t158.{self::Class::[]=}(#t160, #t161){(self::Class*, self::Class*) →* void} in #t161);
+}
+static method operatorAccess(self::Class* c) → void {
+  self::throws(() → self::Class* => (let final self::Class* #t163 = c in #t163 == null ?{self::Class*} null : #t163.{self::Class::field}{self::Class*}).{self::Class::+}(0){(core::int*) →* self::Class*});
+  self::throws(() → self::Class* => (let final self::Class* #t164 = c in #t164 == null ?{self::Class*} null : #t164.{self::Class::field}{self::Class*}).{self::Class::unary-}(){() →* self::Class*});
+  let final self::Class* #t165 = c in #t165 == null ?{self::Class*} null : #t165.{self::Class::field} = #t165.{self::Class::field}{self::Class*}.{self::Class::+}(0){(core::int*) →* self::Class*};
+  c = let final self::Class* #t166 = c in #t166 == null ?{self::Class*} null : let final self::Class* #t167 = #t166.{self::Class::field}{self::Class*}.{self::Class::+}(0){(core::int*) →* self::Class*} in let final void #t168 = #t166.{self::Class::field} = #t167 in #t167;
+  self::throws(() → self::Class* => let final self::Class* #t169 = let final self::Class* #t170 = c in #t170 == null ?{self::Class*} null : #t170.{self::Class::field}{self::Class*} in #t169.{self::Class::field} = #t169.{self::Class::field}{self::Class*}.{self::Class::+}(0){(core::int*) →* self::Class*});
+  self::throws(() → self::Class* => c = let final self::Class* #t171 = let final self::Class* #t172 = c in #t172 == null ?{self::Class*} null : #t172.{self::Class::field}{self::Class*} in #t171.{self::Class::field} = #t171.{self::Class::field}{self::Class*}.{self::Class::+}(0){(core::int*) →* self::Class*});
+  let final self::Class* #t173 = c in #t173 == null ?{self::Class*} null : #t173.{self::Class::field} = #t173.{self::Class::field}{self::Class*}.{self::Class::+}(1){(core::int*) →* self::Class*};
+  c = let final self::Class* #t174 = c in #t174 == null ?{self::Class*} null : let final self::Class* #t175 = #t174.{self::Class::field}{self::Class*} in let final void #t176 = #t174.{self::Class::field} = #t175.{self::Class::+}(1){(core::int*) →* self::Class*} in #t175;
+  let final self::Class* #t177 = c in #t177 == null ?{self::Class*} null : let final self::Class* #t178 = #t177.{self::Class::field}{self::Class*}.{self::Class::+}(1){(core::int*) →* self::Class*} in let final void #t179 = #t177.{self::Class::field} = #t178 in #t178;
+  c = let final self::Class* #t180 = c in #t180 == null ?{self::Class*} null : let final self::Class* #t181 = #t180.{self::Class::field}{self::Class*}.{self::Class::+}(1){(core::int*) →* self::Class*} in let final void #t182 = #t180.{self::Class::field} = #t181 in #t181;
+}
+static method ifNull(self::Class* c) → void {
+  let final self::Class* #t183 = c in #t183 == null ?{self::Class*} null : #t183.{self::Class::field}{self::Class*} == null ?{self::Class*} #t183.{self::Class::field} = c : null;
+  c = let final self::Class* #t184 = c in #t184 == null ?{self::Class*} null : let final self::Class* #t185 = #t184.{self::Class::field}{self::Class*} in #t185 == null ?{self::Class*} #t184.{self::Class::field} = c : #t185;
+  self::throws(() → self::Class* => let final self::Class* #t186 = let final self::Class* #t187 = c in #t187 == null ?{self::Class*} null : #t187.{self::Class::field}{self::Class*} in let final self::Class* #t188 = #t186.{self::Class::field}{self::Class*} in #t188 == null ?{self::Class*} #t186.{self::Class::field} = c : #t188);
+  self::throws(() → self::Class* => c = let final self::Class* #t189 = let final self::Class* #t190 = c in #t190 == null ?{self::Class*} null : #t190.{self::Class::field}{self::Class*} in let final self::Class* #t191 = #t189.{self::Class::field}{self::Class*} in #t191 == null ?{self::Class*} #t189.{self::Class::field} = c : #t191);
+  self::throws(() → self::Class* => let final self::Class* #t192 = let final self::Class* #t193 = c in #t193 == null ?{self::Class*} null : #t193.{self::Class::field}{self::Class*} in let final self::Class* #t194 = c in let final self::Class* #t195 = #t192.{self::Class::[]}(#t194){(self::Class*) →* self::Class*} in #t195 == null ?{self::Class*} let final self::Class* #t196 = c in let final void #t197 = #t192.{self::Class::[]=}(#t194, #t196){(self::Class*, self::Class*) →* void} in #t196 : #t195);
+  self::throws(() → self::Class* => c = let final self::Class* #t198 = let final self::Class* #t199 = c in #t199 == null ?{self::Class*} null : #t199.{self::Class::field}{self::Class*} in let final self::Class* #t200 = c in let final self::Class* #t201 = #t198.{self::Class::[]}(#t200){(self::Class*) →* self::Class*} in #t201 == null ?{self::Class*} let final self::Class* #t202 = c in let final void #t203 = #t198.{self::Class::[]=}(#t200, #t202){(self::Class*, self::Class*) →* void} in #t202 : #t201);
+}
+static method throws(() →* void f) → void {
+  try {
+    f(){() →* void};
+  }
+  on dynamic catch(final dynamic _) {
+    return;
+  }
+  throw "Expected exception.";
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/no_null_shorting_explicit_extension.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/no_null_shorting_explicit_extension.dart.weak.modular.expect
new file mode 100644
index 0000000..f8fa444
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/no_null_shorting_explicit_extension.dart.weak.modular.expect
@@ -0,0 +1,180 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field self::Class* _field = null;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+  get field = self::Extension|get#field;
+  method method = self::Extension|method;
+  tearoff method = self::Extension|get#method;
+  operator [] = self::Extension|[];
+  operator []= = self::Extension|[]=;
+  operator + = self::Extension|+;
+  operator unary- = self::Extension|unary-;
+  set field = self::Extension|set#field;
+}
+static method Extension|get#field(lowered final self::Class* #this) → self::Class*
+  return #this.{self::Class::_field}{self::Class*};
+static method Extension|set#field(lowered final self::Class* #this, self::Class* value) → void {
+  #this.{self::Class::_field} = value;
+}
+static method Extension|method(lowered final self::Class* #this) → self::Class*
+  return self::Extension|get#field(#this);
+static method Extension|get#method(lowered final self::Class* #this) → () →* self::Class*
+  return () → self::Class* => self::Extension|method(#this);
+static method Extension|[](lowered final self::Class* #this, self::Class* key) → self::Class*
+  return self::Extension|get#field(#this);
+static method Extension|[]=(lowered final self::Class* #this, self::Class* key, self::Class* value) → void {
+  self::Extension|set#field(#this, value);
+}
+static method Extension|+(lowered final self::Class* #this, core::int* value) → self::Class*
+  return self::Extension|get#field(#this);
+static method Extension|unary-(lowered final self::Class* #this) → self::Class*
+  return self::Extension|get#field(#this);
+static method main() → dynamic {
+  self::propertyAccess(null);
+  self::indexAccess(null);
+  self::operatorAccess(null);
+  self::ifNull(null);
+}
+static method propertyAccess(self::Class* c) → void {
+  let final self::Class* #t1 = c in #t1 == null ?{self::Class*} null : self::Extension|get#field(#t1);
+  let final self::Class* #t2 = c in #t2 == null ?{self::Class*} null : self::Extension|set#field(#t2, new self::Class::•());
+  c = let final self::Class* #t3 = c in #t3 == null ?{self::Class*} null : let final self::Class* #t4 = new self::Class::•() in let final void #t5 = self::Extension|set#field(#t3, #t4) in #t4;
+  let final self::Class* #t6 = c in #t6 == null ?{self::Class*} null : self::Extension|method(#t6);
+  self::throws(() → self::Class* => self::Extension|get#field(let final self::Class* #t7 = c in #t7 == null ?{self::Class*} null : self::Extension|get#field(#t7)));
+  let final self::Class* #t8 = let final self::Class* #t9 = c in #t9 == null ?{self::Class*} null : self::Extension|get#field(#t9) in #t8 == null ?{self::Class*} null : self::Extension|get#field(#t8);
+  self::throws(() → self::Class* => let final self::Class* #t10 = self::Extension|get#field(let final self::Class* #t11 = c in #t11 == null ?{self::Class*} null : self::Extension|get#field(#t11)) in #t10 == null ?{self::Class*} null : self::Extension|get#field(#t10));
+  self::throws(() → self::Class* => let final self::Class* #t12 = new self::Class::•() in let final void #t13 = self::Extension|set#field(let final self::Class* #t14 = c in #t14 == null ?{self::Class*} null : self::Extension|get#field(#t14), #t12) in #t12);
+  let final self::Class* #t15 = let final self::Class* #t16 = c in #t16 == null ?{self::Class*} null : self::Extension|get#field(#t16) in #t15 == null ?{self::Class*} null : self::Extension|set#field(#t15, new self::Class::•());
+  self::throws(() → self::Class* => let final self::Class* #t17 = self::Extension|get#field(let final self::Class* #t18 = c in #t18 == null ?{self::Class*} null : self::Extension|get#field(#t18)) in #t17 == null ?{self::Class*} null : let final self::Class* #t19 = new self::Class::•() in let final void #t20 = self::Extension|set#field(#t17, #t19) in #t19);
+  self::throws(() → self::Class* => self::Extension|get#field(let final self::Class* #t21 = c in #t21 == null ?{self::Class*} null : self::Extension|get#field(#t21)));
+  self::throws(() → self::Class* => self::Extension|get#field(let final self::Class* #t22 = c in #t22 == null ?{self::Class*} null : let final self::Class* #t23 = new self::Class::•() in let final void #t24 = self::Extension|set#field(#t22, #t23) in #t23));
+  self::throws(() → self::Class* => self::Extension|get#field(let final self::Class* #t25 = c in #t25 == null ?{self::Class*} null : self::Extension|method(#t25)));
+  self::throws(() → self::Class* => c = let final self::Class* #t26 = new self::Class::•() in let final void #t27 = self::Extension|set#field(let final self::Class* #t28 = c in #t28 == null ?{self::Class*} null : self::Extension|get#field(#t28), #t26) in #t26);
+  c = let final self::Class* #t29 = let final self::Class* #t30 = c in #t30 == null ?{self::Class*} null : self::Extension|get#field(#t30) in #t29 == null ?{self::Class*} null : let final self::Class* #t31 = new self::Class::•() in let final void #t32 = self::Extension|set#field(#t29, #t31) in #t31;
+  self::throws(() → self::Class* => c = let final self::Class* #t33 = self::Extension|get#field(let final self::Class* #t34 = c in #t34 == null ?{self::Class*} null : self::Extension|get#field(#t34)) in #t33 == null ?{self::Class*} null : let final self::Class* #t35 = new self::Class::•() in let final void #t36 = self::Extension|set#field(#t33, #t35) in #t35);
+  self::throws(() → self::Class* => self::Extension|method(let final self::Class* #t37 = c in #t37 == null ?{self::Class*} null : self::Extension|get#field(#t37)));
+  let final self::Class* #t38 = c in #t38 == null ?{self::Class*} null : self::Extension|set#field(#t38, self::Extension|get#field(new self::Class::•()));
+  c = let final self::Class* #t39 = c in #t39 == null ?{self::Class*} null : let final self::Class* #t40 = self::Extension|get#field(new self::Class::•()) in let final void #t41 = self::Extension|set#field(#t39, #t40) in #t40;
+  let final self::Class* #t42 = c in #t42 == null ?{self::Class*} null : self::Extension|set#field(#t42, let final self::Class* #t43 = new self::Class::•() in let final void #t44 = self::Extension|set#field(new self::Class::•(), #t43) in #t43);
+  c = let final self::Class* #t45 = c in #t45 == null ?{self::Class*} null : let final self::Class* #t46 = let final self::Class* #t47 = new self::Class::•() in let final void #t48 = self::Extension|set#field(new self::Class::•(), #t47) in #t47 in let final void #t49 = self::Extension|set#field(#t45, #t46) in #t46;
+  let final self::Class* #t50 = c in #t50 == null ?{self::Class*} null : self::Extension|set#field(#t50, self::Extension|method(new self::Class::•()));
+  c = let final self::Class* #t51 = c in #t51 == null ?{self::Class*} null : let final self::Class* #t52 = self::Extension|method(new self::Class::•()) in let final void #t53 = self::Extension|set#field(#t51, #t52) in #t52;
+  self::throws(() → self::Class* => self::Extension|get#field(let final self::Class* #t54 = c in #t54 == null ?{self::Class*} null : self::Extension|method(#t54)));
+  self::throws(() → self::Class* => let final self::Class* #t55 = new self::Class::•() in let final void #t56 = self::Extension|set#field(let final self::Class* #t57 = c in #t57 == null ?{self::Class*} null : self::Extension|method(#t57), #t55) in #t55);
+  self::throws(() → self::Class* => self::Extension|method(let final self::Class* #t58 = c in #t58 == null ?{self::Class*} null : self::Extension|method(#t58)));
+  self::throws(() → self::Class* => self::Extension|get#field(self::Extension|get#field(let final self::Class* #t59 = c in #t59 == null ?{self::Class*} null : self::Extension|get#field(#t59))));
+  self::throws(() → self::Class* => let final self::Class* #t60 = new self::Class::•() in let final void #t61 = self::Extension|set#field(self::Extension|get#field(let final self::Class* #t62 = c in #t62 == null ?{self::Class*} null : self::Extension|get#field(#t62)), #t60) in #t60);
+  self::throws(() → self::Class* => c = let final self::Class* #t63 = new self::Class::•() in let final void #t64 = self::Extension|set#field(self::Extension|get#field(let final self::Class* #t65 = c in #t65 == null ?{self::Class*} null : self::Extension|get#field(#t65)), #t63) in #t63);
+  self::throws(() → self::Class* => self::Extension|method(self::Extension|get#field(let final self::Class* #t66 = c in #t66 == null ?{self::Class*} null : self::Extension|get#field(#t66))));
+  let final self::Class* #t67 = c in #t67 == null ?{self::Class*} null : self::Extension|set#field(#t67, self::Extension|get#field(self::Extension|get#field(new self::Class::•())));
+  c = let final self::Class* #t68 = c in #t68 == null ?{self::Class*} null : let final self::Class* #t69 = self::Extension|get#field(self::Extension|get#field(new self::Class::•())) in let final void #t70 = self::Extension|set#field(#t68, #t69) in #t69;
+  let final self::Class* #t71 = c in #t71 == null ?{self::Class*} null : self::Extension|set#field(#t71, let final self::Class* #t72 = new self::Class::•() in let final void #t73 = self::Extension|set#field(self::Extension|get#field(new self::Class::•()), #t72) in #t72);
+  c = let final self::Class* #t74 = c in #t74 == null ?{self::Class*} null : let final self::Class* #t75 = let final self::Class* #t76 = new self::Class::•() in let final void #t77 = self::Extension|set#field(self::Extension|get#field(new self::Class::•()), #t76) in #t76 in let final void #t78 = self::Extension|set#field(#t74, #t75) in #t75;
+  let final self::Class* #t79 = c in #t79 == null ?{self::Class*} null : self::Extension|set#field(#t79, self::Extension|method(self::Extension|get#field(new self::Class::•())));
+  c = let final self::Class* #t80 = c in #t80 == null ?{self::Class*} null : let final self::Class* #t81 = self::Extension|method(self::Extension|get#field(new self::Class::•())) in let final void #t82 = self::Extension|set#field(#t80, #t81) in #t81;
+  self::throws(() → self::Class* => self::Extension|get#field(self::Extension|get#field(let final self::Class* #t83 = c in #t83 == null ?{self::Class*} null : self::Extension|method(#t83))));
+  self::throws(() → self::Class* => let final self::Class* #t84 = new self::Class::•() in let final void #t85 = self::Extension|set#field(self::Extension|get#field(let final self::Class* #t86 = c in #t86 == null ?{self::Class*} null : self::Extension|method(#t86)), #t84) in #t84);
+  self::throws(() → self::Class* => self::Extension|method(self::Extension|get#field(let final self::Class* #t87 = c in #t87 == null ?{self::Class*} null : self::Extension|method(#t87))));
+  self::throws(() → self::Class* => let final self::Class* #t88 = self::Extension|get#field(new self::Class::•()) in let final void #t89 = self::Extension|set#field(let final self::Class* #t90 = c in #t90 == null ?{self::Class*} null : self::Extension|get#field(#t90), #t88) in #t88);
+  self::throws(() → self::Class* => c = let final self::Class* #t91 = self::Extension|get#field(new self::Class::•()) in let final void #t92 = self::Extension|set#field(let final self::Class* #t93 = c in #t93 == null ?{self::Class*} null : self::Extension|get#field(#t93), #t91) in #t91);
+  self::throws(() → self::Class* => let final self::Class* #t94 = let final self::Class* #t95 = new self::Class::•() in let final void #t96 = self::Extension|set#field(new self::Class::•(), #t95) in #t95 in let final void #t97 = self::Extension|set#field(let final self::Class* #t98 = c in #t98 == null ?{self::Class*} null : self::Extension|get#field(#t98), #t94) in #t94);
+  self::throws(() → self::Class* => c = let final self::Class* #t99 = let final self::Class* #t100 = new self::Class::•() in let final void #t101 = self::Extension|set#field(new self::Class::•(), #t100) in #t100 in let final void #t102 = self::Extension|set#field(let final self::Class* #t103 = c in #t103 == null ?{self::Class*} null : self::Extension|get#field(#t103), #t99) in #t99);
+  self::throws(() → self::Class* => let final self::Class* #t104 = self::Extension|method(new self::Class::•()) in let final void #t105 = self::Extension|set#field(let final self::Class* #t106 = c in #t106 == null ?{self::Class*} null : self::Extension|get#field(#t106), #t104) in #t104);
+  self::throws(() → self::Class* => c = let final self::Class* #t107 = self::Extension|method(new self::Class::•()) in let final void #t108 = self::Extension|set#field(let final self::Class* #t109 = c in #t109 == null ?{self::Class*} null : self::Extension|get#field(#t109), #t107) in #t107);
+  let final self::Class* #t110 = c in #t110 == null ?{self::Class*} null : self::Extension|set#field(#t110, let final self::Class* #t111 = self::Extension|get#field(new self::Class::•()) in let final void #t112 = self::Extension|set#field(new self::Class::•(), #t111) in #t111);
+  c = let final self::Class* #t113 = c in #t113 == null ?{self::Class*} null : let final self::Class* #t114 = let final self::Class* #t115 = self::Extension|get#field(new self::Class::•()) in let final void #t116 = self::Extension|set#field(new self::Class::•(), #t115) in #t115 in let final void #t117 = self::Extension|set#field(#t113, #t114) in #t114;
+  let final self::Class* #t118 = c in #t118 == null ?{self::Class*} null : self::Extension|set#field(#t118, let final self::Class* #t119 = let final self::Class* #t120 = new self::Class::•() in let final void #t121 = self::Extension|set#field(new self::Class::•(), #t120) in #t120 in let final void #t122 = self::Extension|set#field(new self::Class::•(), #t119) in #t119);
+  c = let final self::Class* #t123 = c in #t123 == null ?{self::Class*} null : let final self::Class* #t124 = let final self::Class* #t125 = let final self::Class* #t126 = new self::Class::•() in let final void #t127 = self::Extension|set#field(new self::Class::•(), #t126) in #t126 in let final void #t128 = self::Extension|set#field(new self::Class::•(), #t125) in #t125 in let final void #t129 = self::Extension|set#field(#t123, #t124) in #t124;
+  let final self::Class* #t130 = c in #t130 == null ?{self::Class*} null : self::Extension|set#field(#t130, let final self::Class* #t131 = self::Extension|method(new self::Class::•()) in let final void #t132 = self::Extension|set#field(new self::Class::•(), #t131) in #t131);
+  c = let final self::Class* #t133 = c in #t133 == null ?{self::Class*} null : let final self::Class* #t134 = let final self::Class* #t135 = self::Extension|method(new self::Class::•()) in let final void #t136 = self::Extension|set#field(new self::Class::•(), #t135) in #t135 in let final void #t137 = self::Extension|set#field(#t133, #t134) in #t134;
+  self::throws(() → self::Class* => let final self::Class* #t138 = self::Extension|get#field(new self::Class::•()) in let final void #t139 = self::Extension|set#field(let final self::Class* #t140 = c in #t140 == null ?{self::Class*} null : self::Extension|method(#t140), #t138) in #t138);
+  self::throws(() → self::Class* => c = let final self::Class* #t141 = self::Extension|get#field(new self::Class::•()) in let final void #t142 = self::Extension|set#field(let final self::Class* #t143 = c in #t143 == null ?{self::Class*} null : self::Extension|method(#t143), #t141) in #t141);
+  self::throws(() → self::Class* => let final self::Class* #t144 = let final self::Class* #t145 = new self::Class::•() in let final void #t146 = self::Extension|set#field(new self::Class::•(), #t145) in #t145 in let final void #t147 = self::Extension|set#field(let final self::Class* #t148 = c in #t148 == null ?{self::Class*} null : self::Extension|method(#t148), #t144) in #t144);
+  self::throws(() → self::Class* => c = let final self::Class* #t149 = let final self::Class* #t150 = new self::Class::•() in let final void #t151 = self::Extension|set#field(new self::Class::•(), #t150) in #t150 in let final void #t152 = self::Extension|set#field(let final self::Class* #t153 = c in #t153 == null ?{self::Class*} null : self::Extension|method(#t153), #t149) in #t149);
+  self::throws(() → self::Class* => let final self::Class* #t154 = self::Extension|method(new self::Class::•()) in let final void #t155 = self::Extension|set#field(let final self::Class* #t156 = c in #t156 == null ?{self::Class*} null : self::Extension|method(#t156), #t154) in #t154);
+  self::throws(() → self::Class* => c = let final self::Class* #t157 = self::Extension|method(new self::Class::•()) in let final void #t158 = self::Extension|set#field(let final self::Class* #t159 = c in #t159 == null ?{self::Class*} null : self::Extension|method(#t159), #t157) in #t157);
+  self::throws(() → self::Class* => self::Extension|get#field(self::Extension|method(let final self::Class* #t160 = c in #t160 == null ?{self::Class*} null : self::Extension|get#field(#t160))));
+  self::throws(() → self::Class* => let final self::Class* #t161 = new self::Class::•() in let final void #t162 = self::Extension|set#field(self::Extension|method(let final self::Class* #t163 = c in #t163 == null ?{self::Class*} null : self::Extension|get#field(#t163)), #t161) in #t161);
+  self::throws(() → self::Class* => c = let final self::Class* #t164 = new self::Class::•() in let final void #t165 = self::Extension|set#field(self::Extension|method(let final self::Class* #t166 = c in #t166 == null ?{self::Class*} null : self::Extension|get#field(#t166)), #t164) in #t164);
+  self::throws(() → self::Class* => self::Extension|method(self::Extension|method(let final self::Class* #t167 = c in #t167 == null ?{self::Class*} null : self::Extension|get#field(#t167))));
+  let final self::Class* #t168 = c in #t168 == null ?{self::Class*} null : self::Extension|set#field(#t168, self::Extension|get#field(self::Extension|method(new self::Class::•())));
+  c = let final self::Class* #t169 = c in #t169 == null ?{self::Class*} null : let final self::Class* #t170 = self::Extension|get#field(self::Extension|method(new self::Class::•())) in let final void #t171 = self::Extension|set#field(#t169, #t170) in #t170;
+  let final self::Class* #t172 = c in #t172 == null ?{self::Class*} null : self::Extension|set#field(#t172, let final self::Class* #t173 = new self::Class::•() in let final void #t174 = self::Extension|set#field(self::Extension|method(new self::Class::•()), #t173) in #t173);
+  c = let final self::Class* #t175 = c in #t175 == null ?{self::Class*} null : let final self::Class* #t176 = let final self::Class* #t177 = new self::Class::•() in let final void #t178 = self::Extension|set#field(self::Extension|method(new self::Class::•()), #t177) in #t177 in let final void #t179 = self::Extension|set#field(#t175, #t176) in #t176;
+  let final self::Class* #t180 = c in #t180 == null ?{self::Class*} null : self::Extension|set#field(#t180, self::Extension|method(self::Extension|method(new self::Class::•())));
+  c = let final self::Class* #t181 = c in #t181 == null ?{self::Class*} null : let final self::Class* #t182 = self::Extension|method(self::Extension|method(new self::Class::•())) in let final void #t183 = self::Extension|set#field(#t181, #t182) in #t182;
+  self::throws(() → self::Class* => self::Extension|get#field(self::Extension|method(let final self::Class* #t184 = c in #t184 == null ?{self::Class*} null : self::Extension|method(#t184))));
+  self::throws(() → self::Class* => let final self::Class* #t185 = new self::Class::•() in let final void #t186 = self::Extension|set#field(self::Extension|method(let final self::Class* #t187 = c in #t187 == null ?{self::Class*} null : self::Extension|method(#t187)), #t185) in #t185);
+  self::throws(() → self::Class* => self::Extension|method(self::Extension|method(let final self::Class* #t188 = c in #t188 == null ?{self::Class*} null : self::Extension|method(#t188))));
+  let final self::Class* #t189 = let final self::Class* #t190 = c in #t190 == null ?{self::Class*} null : self::Extension|method(#t190) in #t189 == null ?{self::Class*} null : self::Extension|method(#t189);
+  self::throws(() → self::Class* => self::Extension|get#field(let final self::Class* #t191 = c in #t191 == null ?{self::Class*} null : self::Extension|get#field(#t191)));
+  let final self::Class* #t192 = let final self::Class* #t193 = c in #t193 == null ?{self::Class*} null : self::Extension|get#field(#t193) in #t192 == null ?{self::Class*} null : self::Extension|get#field(#t192);
+}
+static method indexAccess(self::Class* c) → void {
+  self::throws(() → self::Class* => self::Extension|[](let final self::Class* #t194 = c in #t194 == null ?{self::Class*} null : self::Extension|get#field(#t194), c));
+  self::throws(() → self::Class* => let final self::Class* #t195 = let final self::Class* #t196 = c in #t196 == null ?{self::Class*} null : self::Extension|get#field(#t196) in let final self::Class* #t197 = c in let final self::Class* #t198 = new self::Class::•() in let final void #t199 = self::Extension|[]=(#t195, #t197, #t198) in #t198);
+  self::throws(() → self::Class* => c = let final self::Class* #t200 = let final self::Class* #t201 = c in #t201 == null ?{self::Class*} null : self::Extension|get#field(#t201) in let final self::Class* #t202 = c in let final self::Class* #t203 = new self::Class::•() in let final void #t204 = self::Extension|[]=(#t200, #t202, #t203) in #t203);
+  self::throws(() → self::Class* => self::Extension|method(self::Extension|[](let final self::Class* #t205 = c in #t205 == null ?{self::Class*} null : self::Extension|get#field(#t205), c)));
+  self::throws(() → self::Class* => let final self::Class* #t206 = let final self::Class* #t207 = c in #t207 == null ?{self::Class*} null : self::Extension|get#field(#t207) in let final self::Class* #t208 = c in let final self::Class* #t209 = self::Extension|+(self::Extension|[](#t206, #t208), 0) in let final void #t210 = self::Extension|[]=(#t206, #t208, #t209) in #t209);
+  self::throws(() → self::Class* => c = let final self::Class* #t211 = let final self::Class* #t212 = c in #t212 == null ?{self::Class*} null : self::Extension|get#field(#t212) in let final self::Class* #t213 = c in let final self::Class* #t214 = self::Extension|+(self::Extension|[](#t211, #t213), 0) in let final void #t215 = self::Extension|[]=(#t211, #t213, #t214) in #t214);
+  self::throws(() → self::Class* => let final self::Class* #t216 = let final self::Class* #t217 = c in #t217 == null ?{self::Class*} null : self::Extension|get#field(#t217) in let final self::Class* #t218 = c in let final self::Class* #t219 = self::Extension|[](#t216, #t218) in let final void #t220 = self::Extension|[]=(#t216, #t218, self::Extension|+(#t219, 1)) in #t219);
+  self::throws(() → self::Class* => c = let final self::Class* #t221 = let final self::Class* #t222 = c in #t222 == null ?{self::Class*} null : self::Extension|get#field(#t222) in let final self::Class* #t223 = c in let final self::Class* #t224 = self::Extension|[](#t221, #t223) in let final void #t225 = self::Extension|[]=(#t221, #t223, self::Extension|+(#t224, 1)) in #t224);
+  self::throws(() → self::Class* => let final self::Class* #t226 = let final self::Class* #t227 = c in #t227 == null ?{self::Class*} null : self::Extension|get#field(#t227) in let final self::Class* #t228 = c in let final self::Class* #t229 = self::Extension|+(self::Extension|[](#t226, #t228), 1) in let final void #t230 = self::Extension|[]=(#t226, #t228, #t229) in #t229);
+  self::throws(() → self::Class* => c = let final self::Class* #t231 = let final self::Class* #t232 = c in #t232 == null ?{self::Class*} null : self::Extension|get#field(#t232) in let final self::Class* #t233 = c in let final self::Class* #t234 = self::Extension|+(self::Extension|[](#t231, #t233), 1) in let final void #t235 = self::Extension|[]=(#t231, #t233, #t234) in #t234);
+  self::throws(() → self::Class* => self::Extension|[](self::Extension|[](let final self::Class* #t236 = c in #t236 == null ?{self::Class*} null : self::Extension|get#field(#t236), c), c));
+  self::throws(() → self::Class* => let final self::Class* #t237 = self::Extension|[](let final self::Class* #t238 = c in #t238 == null ?{self::Class*} null : self::Extension|get#field(#t238), c) in let final self::Class* #t239 = c in let final self::Class* #t240 = new self::Class::•() in let final void #t241 = self::Extension|[]=(#t237, #t239, #t240) in #t240);
+  self::throws(() → self::Class* => c = let final self::Class* #t242 = self::Extension|[](let final self::Class* #t243 = c in #t243 == null ?{self::Class*} null : self::Extension|get#field(#t243), c) in let final self::Class* #t244 = c in let final self::Class* #t245 = new self::Class::•() in let final void #t246 = self::Extension|[]=(#t242, #t244, #t245) in #t245);
+  self::throws(() → self::Class* => self::Extension|method(self::Extension|[](self::Extension|[](let final self::Class* #t247 = c in #t247 == null ?{self::Class*} null : self::Extension|get#field(#t247), c), c)));
+  self::throws(() → self::Class* => let final self::Class* #t248 = self::Extension|[](let final self::Class* #t249 = c in #t249 == null ?{self::Class*} null : self::Extension|get#field(#t249), c) in let final self::Class* #t250 = c in let final self::Class* #t251 = self::Extension|+(self::Extension|[](#t248, #t250), 0) in let final void #t252 = self::Extension|[]=(#t248, #t250, #t251) in #t251);
+  self::throws(() → self::Class* => c = let final self::Class* #t253 = self::Extension|[](let final self::Class* #t254 = c in #t254 == null ?{self::Class*} null : self::Extension|get#field(#t254), c) in let final self::Class* #t255 = c in let final self::Class* #t256 = self::Extension|+(self::Extension|[](#t253, #t255), 0) in let final void #t257 = self::Extension|[]=(#t253, #t255, #t256) in #t256);
+  self::throws(() → self::Class* => let final self::Class* #t258 = self::Extension|[](let final self::Class* #t259 = c in #t259 == null ?{self::Class*} null : self::Extension|get#field(#t259), c) in let final self::Class* #t260 = c in let final self::Class* #t261 = self::Extension|[](#t258, #t260) in let final void #t262 = self::Extension|[]=(#t258, #t260, self::Extension|+(#t261, 1)) in #t261);
+  self::throws(() → self::Class* => c = let final self::Class* #t263 = self::Extension|[](let final self::Class* #t264 = c in #t264 == null ?{self::Class*} null : self::Extension|get#field(#t264), c) in let final self::Class* #t265 = c in let final self::Class* #t266 = self::Extension|[](#t263, #t265) in let final void #t267 = self::Extension|[]=(#t263, #t265, self::Extension|+(#t266, 1)) in #t266);
+  self::throws(() → self::Class* => let final self::Class* #t268 = self::Extension|[](let final self::Class* #t269 = c in #t269 == null ?{self::Class*} null : self::Extension|get#field(#t269), c) in let final self::Class* #t270 = c in let final self::Class* #t271 = self::Extension|+(self::Extension|[](#t268, #t270), 1) in let final void #t272 = self::Extension|[]=(#t268, #t270, #t271) in #t271);
+  self::throws(() → self::Class* => c = let final self::Class* #t273 = self::Extension|[](let final self::Class* #t274 = c in #t274 == null ?{self::Class*} null : self::Extension|get#field(#t274), c) in let final self::Class* #t275 = c in let final self::Class* #t276 = self::Extension|+(self::Extension|[](#t273, #t275), 1) in let final void #t277 = self::Extension|[]=(#t273, #t275, #t276) in #t276);
+}
+static method operatorAccess(self::Class* c) → void {
+  self::throws(() → self::Class* => self::Extension|+(let final self::Class* #t278 = c in #t278 == null ?{self::Class*} null : self::Extension|get#field(#t278), 0));
+  self::throws(() → self::Class* => self::Extension|unary-(let final self::Class* #t279 = c in #t279 == null ?{self::Class*} null : self::Extension|get#field(#t279)));
+  let final self::Class* #t280 = c in #t280 == null ?{self::Class*} null : self::Extension|set#field(#t280, self::Extension|+(self::Extension|get#field(#t280), 0));
+  c = let final self::Class* #t281 = c in #t281 == null ?{self::Class*} null : let final self::Class* #t282 = self::Extension|+(self::Extension|get#field(#t281), 0) in let final void #t283 = self::Extension|set#field(#t281, #t282) in #t282;
+  self::throws(() → self::Class* => let final self::Class* #t284 = let final self::Class* #t285 = c in #t285 == null ?{self::Class*} null : self::Extension|get#field(#t285) in let final self::Class* #t286 = self::Extension|+(self::Extension|get#field(#t284), 0) in let final void #t287 = self::Extension|set#field(#t284, #t286) in #t286);
+  self::throws(() → self::Class* => c = let final self::Class* #t288 = let final self::Class* #t289 = c in #t289 == null ?{self::Class*} null : self::Extension|get#field(#t289) in let final self::Class* #t290 = self::Extension|+(self::Extension|get#field(#t288), 0) in let final void #t291 = self::Extension|set#field(#t288, #t290) in #t290);
+  let final self::Class* #t292 = c in #t292 == null ?{self::Class*} null : self::Extension|set#field(#t292, self::Extension|+(self::Extension|get#field(#t292), 1));
+  c = let final self::Class* #t293 = c in #t293 == null ?{self::Class*} null : let final self::Class* #t294 = self::Extension|get#field(#t293) in let final self::Class* #t295 = let final self::Class* #t296 = self::Extension|+(#t294, 1) in let final void #t297 = self::Extension|set#field(#t293, #t296) in #t296 in #t294;
+  let final self::Class* #t298 = c in #t298 == null ?{self::Class*} null : let final self::Class* #t299 = self::Extension|+(self::Extension|get#field(#t298), 1) in let final void #t300 = self::Extension|set#field(#t298, #t299) in #t299;
+  c = let final self::Class* #t301 = c in #t301 == null ?{self::Class*} null : let final self::Class* #t302 = self::Extension|+(self::Extension|get#field(#t301), 1) in let final void #t303 = self::Extension|set#field(#t301, #t302) in #t302;
+}
+static method ifNull(self::Class* c) → void {
+  let final self::Class* #t304 = c in #t304 == null ?{self::Class*} null : self::Extension|get#field(#t304) == null ?{self::Class*} self::Extension|set#field(#t304, c) : null;
+  c = let final self::Class* #t305 = c in #t305 == null ?{self::Class*} null : let final self::Class* #t306 = self::Extension|get#field(#t305) in #t306 == null ?{self::Class*} let final self::Class* #t307 = c in let final void #t308 = self::Extension|set#field(#t305, #t307) in #t307 : #t306;
+  self::throws(() → self::Class* => let final self::Class* #t309 = let final self::Class* #t310 = c in #t310 == null ?{self::Class*} null : self::Extension|get#field(#t310) in let final self::Class* #t311 = self::Extension|get#field(#t309) in #t311 == null ?{self::Class*} let final self::Class* #t312 = c in let final void #t313 = self::Extension|set#field(#t309, #t312) in #t312 : #t311);
+  self::throws(() → self::Class* => c = let final self::Class* #t314 = let final self::Class* #t315 = c in #t315 == null ?{self::Class*} null : self::Extension|get#field(#t315) in let final self::Class* #t316 = self::Extension|get#field(#t314) in #t316 == null ?{self::Class*} let final self::Class* #t317 = c in let final void #t318 = self::Extension|set#field(#t314, #t317) in #t317 : #t316);
+  self::throws(() → self::Class* => let final self::Class* #t319 = let final self::Class* #t320 = c in #t320 == null ?{self::Class*} null : self::Extension|get#field(#t320) in let final self::Class* #t321 = c in let final self::Class* #t322 = self::Extension|[](#t319, #t321) in #t322 == null ?{self::Class*} let final self::Class* #t323 = c in let final void #t324 = self::Extension|[]=(#t319, #t321, #t323) in #t323 : #t322);
+  self::throws(() → self::Class* => c = let final self::Class* #t325 = let final self::Class* #t326 = c in #t326 == null ?{self::Class*} null : self::Extension|get#field(#t326) in let final self::Class* #t327 = c in let final self::Class* #t328 = self::Extension|[](#t325, #t327) in #t328 == null ?{self::Class*} let final self::Class* #t329 = c in let final void #t330 = self::Extension|[]=(#t325, #t327, #t329) in #t329 : #t328);
+}
+static method throws(() →* void f) → void {
+  try {
+    f(){() →* void};
+  }
+  on dynamic catch(final dynamic _) {
+    return;
+  }
+  throw "Expected exception.";
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/no_null_shorting_extension.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/no_null_shorting_extension.dart.weak.modular.expect
new file mode 100644
index 0000000..ce52b2a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/no_null_shorting_extension.dart.weak.modular.expect
@@ -0,0 +1,178 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field self::Class* _field = null;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension Extension on self::Class* {
+  get field = self::Extension|get#field;
+  method method = self::Extension|method;
+  tearoff method = self::Extension|get#method;
+  operator [] = self::Extension|[];
+  operator []= = self::Extension|[]=;
+  operator + = self::Extension|+;
+  operator unary- = self::Extension|unary-;
+  set field = self::Extension|set#field;
+}
+static method Extension|get#field(lowered final self::Class* #this) → self::Class*
+  return #this.{self::Class::_field}{self::Class*};
+static method Extension|set#field(lowered final self::Class* #this, self::Class* value) → void {
+  #this.{self::Class::_field} = value;
+}
+static method Extension|method(lowered final self::Class* #this) → self::Class*
+  return self::Extension|get#field(#this);
+static method Extension|get#method(lowered final self::Class* #this) → () →* self::Class*
+  return () → self::Class* => self::Extension|method(#this);
+static method Extension|[](lowered final self::Class* #this, self::Class* key) → self::Class*
+  return self::Extension|get#field(#this);
+static method Extension|[]=(lowered final self::Class* #this, self::Class* key, self::Class* value) → void {
+  self::Extension|set#field(#this, value);
+}
+static method Extension|+(lowered final self::Class* #this, core::int* value) → self::Class*
+  return self::Extension|get#field(#this);
+static method Extension|unary-(lowered final self::Class* #this) → self::Class*
+  return self::Extension|get#field(#this);
+static method main() → dynamic {
+  self::propertyAccess(null);
+  self::indexAccess(null);
+  self::operatorAccess(null);
+  self::ifNull(null);
+}
+static method propertyAccess(self::Class* c) → void {
+  let final self::Class* #t1 = c in #t1 == null ?{self::Class*} null : self::Extension|get#field(#t1);
+  let final self::Class* #t2 = c in #t2 == null ?{self::Class*} null : self::Extension|set#field(#t2, new self::Class::•());
+  c = let final self::Class* #t3 = c in #t3 == null ?{self::Class*} null : let final self::Class* #t4 = new self::Class::•() in let final void #t5 = self::Extension|set#field(#t3, #t4) in #t4;
+  let final self::Class* #t6 = c in #t6 == null ?{self::Class*} null : self::Extension|method(#t6);
+  self::throws(() → self::Class* => self::Extension|get#field(let final self::Class* #t7 = c in #t7 == null ?{self::Class*} null : self::Extension|get#field(#t7)));
+  let final self::Class* #t8 = let final self::Class* #t9 = c in #t9 == null ?{self::Class*} null : self::Extension|get#field(#t9) in #t8 == null ?{self::Class*} null : self::Extension|get#field(#t8);
+  self::throws(() → self::Class* => let final self::Class* #t10 = self::Extension|get#field(let final self::Class* #t11 = c in #t11 == null ?{self::Class*} null : self::Extension|get#field(#t11)) in #t10 == null ?{self::Class*} null : self::Extension|get#field(#t10));
+  self::throws(() → self::Class* => let final self::Class* #t12 = new self::Class::•() in let final void #t13 = self::Extension|set#field(let final self::Class* #t14 = c in #t14 == null ?{self::Class*} null : self::Extension|get#field(#t14), #t12) in #t12);
+  let final self::Class* #t15 = let final self::Class* #t16 = c in #t16 == null ?{self::Class*} null : self::Extension|get#field(#t16) in #t15 == null ?{self::Class*} null : self::Extension|set#field(#t15, new self::Class::•());
+  self::throws(() → self::Class* => let final self::Class* #t17 = self::Extension|get#field(let final self::Class* #t18 = c in #t18 == null ?{self::Class*} null : self::Extension|get#field(#t18)) in #t17 == null ?{self::Class*} null : let final self::Class* #t19 = new self::Class::•() in let final void #t20 = self::Extension|set#field(#t17, #t19) in #t19);
+  self::throws(() → self::Class* => self::Extension|get#field(let final self::Class* #t21 = c in #t21 == null ?{self::Class*} null : self::Extension|get#field(#t21)));
+  self::throws(() → self::Class* => self::Extension|get#field(let final self::Class* #t22 = c in #t22 == null ?{self::Class*} null : let final self::Class* #t23 = new self::Class::•() in let final void #t24 = self::Extension|set#field(#t22, #t23) in #t23));
+  self::throws(() → self::Class* => self::Extension|get#field(let final self::Class* #t25 = c in #t25 == null ?{self::Class*} null : self::Extension|method(#t25)));
+  self::throws(() → self::Class* => c = let final self::Class* #t26 = new self::Class::•() in let final void #t27 = self::Extension|set#field(let final self::Class* #t28 = c in #t28 == null ?{self::Class*} null : self::Extension|get#field(#t28), #t26) in #t26);
+  c = let final self::Class* #t29 = let final self::Class* #t30 = c in #t30 == null ?{self::Class*} null : self::Extension|get#field(#t30) in #t29 == null ?{self::Class*} null : let final self::Class* #t31 = new self::Class::•() in let final void #t32 = self::Extension|set#field(#t29, #t31) in #t31;
+  self::throws(() → self::Class* => c = let final self::Class* #t33 = self::Extension|get#field(let final self::Class* #t34 = c in #t34 == null ?{self::Class*} null : self::Extension|get#field(#t34)) in #t33 == null ?{self::Class*} null : let final self::Class* #t35 = new self::Class::•() in let final void #t36 = self::Extension|set#field(#t33, #t35) in #t35);
+  self::throws(() → self::Class* => self::Extension|method(let final self::Class* #t37 = c in #t37 == null ?{self::Class*} null : self::Extension|get#field(#t37)));
+  let final self::Class* #t38 = c in #t38 == null ?{self::Class*} null : self::Extension|set#field(#t38, self::Extension|get#field(new self::Class::•()));
+  c = let final self::Class* #t39 = c in #t39 == null ?{self::Class*} null : let final self::Class* #t40 = self::Extension|get#field(new self::Class::•()) in let final void #t41 = self::Extension|set#field(#t39, #t40) in #t40;
+  let final self::Class* #t42 = c in #t42 == null ?{self::Class*} null : self::Extension|set#field(#t42, let final self::Class* #t43 = new self::Class::•() in let final void #t44 = self::Extension|set#field(new self::Class::•(), #t43) in #t43);
+  c = let final self::Class* #t45 = c in #t45 == null ?{self::Class*} null : let final self::Class* #t46 = let final self::Class* #t47 = new self::Class::•() in let final void #t48 = self::Extension|set#field(new self::Class::•(), #t47) in #t47 in let final void #t49 = self::Extension|set#field(#t45, #t46) in #t46;
+  let final self::Class* #t50 = c in #t50 == null ?{self::Class*} null : self::Extension|set#field(#t50, self::Extension|method(new self::Class::•()));
+  c = let final self::Class* #t51 = c in #t51 == null ?{self::Class*} null : let final self::Class* #t52 = self::Extension|method(new self::Class::•()) in let final void #t53 = self::Extension|set#field(#t51, #t52) in #t52;
+  self::throws(() → self::Class* => self::Extension|get#field(let final self::Class* #t54 = c in #t54 == null ?{self::Class*} null : self::Extension|method(#t54)));
+  self::throws(() → self::Class* => let final self::Class* #t55 = new self::Class::•() in let final void #t56 = self::Extension|set#field(let final self::Class* #t57 = c in #t57 == null ?{self::Class*} null : self::Extension|method(#t57), #t55) in #t55);
+  self::throws(() → self::Class* => self::Extension|method(let final self::Class* #t58 = c in #t58 == null ?{self::Class*} null : self::Extension|method(#t58)));
+  self::throws(() → self::Class* => self::Extension|get#field(self::Extension|get#field(let final self::Class* #t59 = c in #t59 == null ?{self::Class*} null : self::Extension|get#field(#t59))));
+  self::throws(() → self::Class* => let final self::Class* #t60 = new self::Class::•() in let final void #t61 = self::Extension|set#field(self::Extension|get#field(let final self::Class* #t62 = c in #t62 == null ?{self::Class*} null : self::Extension|get#field(#t62)), #t60) in #t60);
+  self::throws(() → self::Class* => c = let final self::Class* #t63 = new self::Class::•() in let final void #t64 = self::Extension|set#field(self::Extension|get#field(let final self::Class* #t65 = c in #t65 == null ?{self::Class*} null : self::Extension|get#field(#t65)), #t63) in #t63);
+  self::throws(() → self::Class* => self::Extension|method(self::Extension|get#field(let final self::Class* #t66 = c in #t66 == null ?{self::Class*} null : self::Extension|get#field(#t66))));
+  let final self::Class* #t67 = c in #t67 == null ?{self::Class*} null : self::Extension|set#field(#t67, self::Extension|get#field(self::Extension|get#field(new self::Class::•())));
+  c = let final self::Class* #t68 = c in #t68 == null ?{self::Class*} null : let final self::Class* #t69 = self::Extension|get#field(self::Extension|get#field(new self::Class::•())) in let final void #t70 = self::Extension|set#field(#t68, #t69) in #t69;
+  let final self::Class* #t71 = c in #t71 == null ?{self::Class*} null : self::Extension|set#field(#t71, let final self::Class* #t72 = new self::Class::•() in let final void #t73 = self::Extension|set#field(self::Extension|get#field(new self::Class::•()), #t72) in #t72);
+  c = let final self::Class* #t74 = c in #t74 == null ?{self::Class*} null : let final self::Class* #t75 = let final self::Class* #t76 = new self::Class::•() in let final void #t77 = self::Extension|set#field(self::Extension|get#field(new self::Class::•()), #t76) in #t76 in let final void #t78 = self::Extension|set#field(#t74, #t75) in #t75;
+  let final self::Class* #t79 = c in #t79 == null ?{self::Class*} null : self::Extension|set#field(#t79, self::Extension|method(self::Extension|get#field(new self::Class::•())));
+  c = let final self::Class* #t80 = c in #t80 == null ?{self::Class*} null : let final self::Class* #t81 = self::Extension|method(self::Extension|get#field(new self::Class::•())) in let final void #t82 = self::Extension|set#field(#t80, #t81) in #t81;
+  self::throws(() → self::Class* => self::Extension|get#field(self::Extension|get#field(let final self::Class* #t83 = c in #t83 == null ?{self::Class*} null : self::Extension|method(#t83))));
+  self::throws(() → self::Class* => let final self::Class* #t84 = new self::Class::•() in let final void #t85 = self::Extension|set#field(self::Extension|get#field(let final self::Class* #t86 = c in #t86 == null ?{self::Class*} null : self::Extension|method(#t86)), #t84) in #t84);
+  self::throws(() → self::Class* => self::Extension|method(self::Extension|get#field(let final self::Class* #t87 = c in #t87 == null ?{self::Class*} null : self::Extension|method(#t87))));
+  self::throws(() → self::Class* => let final self::Class* #t88 = self::Extension|get#field(new self::Class::•()) in let final void #t89 = self::Extension|set#field(let final self::Class* #t90 = c in #t90 == null ?{self::Class*} null : self::Extension|get#field(#t90), #t88) in #t88);
+  self::throws(() → self::Class* => c = let final self::Class* #t91 = self::Extension|get#field(new self::Class::•()) in let final void #t92 = self::Extension|set#field(let final self::Class* #t93 = c in #t93 == null ?{self::Class*} null : self::Extension|get#field(#t93), #t91) in #t91);
+  self::throws(() → self::Class* => let final self::Class* #t94 = let final self::Class* #t95 = new self::Class::•() in let final void #t96 = self::Extension|set#field(new self::Class::•(), #t95) in #t95 in let final void #t97 = self::Extension|set#field(let final self::Class* #t98 = c in #t98 == null ?{self::Class*} null : self::Extension|get#field(#t98), #t94) in #t94);
+  self::throws(() → self::Class* => c = let final self::Class* #t99 = let final self::Class* #t100 = new self::Class::•() in let final void #t101 = self::Extension|set#field(new self::Class::•(), #t100) in #t100 in let final void #t102 = self::Extension|set#field(let final self::Class* #t103 = c in #t103 == null ?{self::Class*} null : self::Extension|get#field(#t103), #t99) in #t99);
+  self::throws(() → self::Class* => let final self::Class* #t104 = self::Extension|method(new self::Class::•()) in let final void #t105 = self::Extension|set#field(let final self::Class* #t106 = c in #t106 == null ?{self::Class*} null : self::Extension|get#field(#t106), #t104) in #t104);
+  self::throws(() → self::Class* => c = let final self::Class* #t107 = self::Extension|method(new self::Class::•()) in let final void #t108 = self::Extension|set#field(let final self::Class* #t109 = c in #t109 == null ?{self::Class*} null : self::Extension|get#field(#t109), #t107) in #t107);
+  let final self::Class* #t110 = c in #t110 == null ?{self::Class*} null : self::Extension|set#field(#t110, let final self::Class* #t111 = self::Extension|get#field(new self::Class::•()) in let final void #t112 = self::Extension|set#field(new self::Class::•(), #t111) in #t111);
+  c = let final self::Class* #t113 = c in #t113 == null ?{self::Class*} null : let final self::Class* #t114 = let final self::Class* #t115 = self::Extension|get#field(new self::Class::•()) in let final void #t116 = self::Extension|set#field(new self::Class::•(), #t115) in #t115 in let final void #t117 = self::Extension|set#field(#t113, #t114) in #t114;
+  let final self::Class* #t118 = c in #t118 == null ?{self::Class*} null : self::Extension|set#field(#t118, let final self::Class* #t119 = let final self::Class* #t120 = new self::Class::•() in let final void #t121 = self::Extension|set#field(new self::Class::•(), #t120) in #t120 in let final void #t122 = self::Extension|set#field(new self::Class::•(), #t119) in #t119);
+  c = let final self::Class* #t123 = c in #t123 == null ?{self::Class*} null : let final self::Class* #t124 = let final self::Class* #t125 = let final self::Class* #t126 = new self::Class::•() in let final void #t127 = self::Extension|set#field(new self::Class::•(), #t126) in #t126 in let final void #t128 = self::Extension|set#field(new self::Class::•(), #t125) in #t125 in let final void #t129 = self::Extension|set#field(#t123, #t124) in #t124;
+  let final self::Class* #t130 = c in #t130 == null ?{self::Class*} null : self::Extension|set#field(#t130, let final self::Class* #t131 = self::Extension|method(new self::Class::•()) in let final void #t132 = self::Extension|set#field(new self::Class::•(), #t131) in #t131);
+  c = let final self::Class* #t133 = c in #t133 == null ?{self::Class*} null : let final self::Class* #t134 = let final self::Class* #t135 = self::Extension|method(new self::Class::•()) in let final void #t136 = self::Extension|set#field(new self::Class::•(), #t135) in #t135 in let final void #t137 = self::Extension|set#field(#t133, #t134) in #t134;
+  self::throws(() → self::Class* => let final self::Class* #t138 = self::Extension|get#field(new self::Class::•()) in let final void #t139 = self::Extension|set#field(let final self::Class* #t140 = c in #t140 == null ?{self::Class*} null : self::Extension|method(#t140), #t138) in #t138);
+  self::throws(() → self::Class* => c = let final self::Class* #t141 = self::Extension|get#field(new self::Class::•()) in let final void #t142 = self::Extension|set#field(let final self::Class* #t143 = c in #t143 == null ?{self::Class*} null : self::Extension|method(#t143), #t141) in #t141);
+  self::throws(() → self::Class* => let final self::Class* #t144 = let final self::Class* #t145 = new self::Class::•() in let final void #t146 = self::Extension|set#field(new self::Class::•(), #t145) in #t145 in let final void #t147 = self::Extension|set#field(let final self::Class* #t148 = c in #t148 == null ?{self::Class*} null : self::Extension|method(#t148), #t144) in #t144);
+  self::throws(() → self::Class* => c = let final self::Class* #t149 = let final self::Class* #t150 = new self::Class::•() in let final void #t151 = self::Extension|set#field(new self::Class::•(), #t150) in #t150 in let final void #t152 = self::Extension|set#field(let final self::Class* #t153 = c in #t153 == null ?{self::Class*} null : self::Extension|method(#t153), #t149) in #t149);
+  self::throws(() → self::Class* => let final self::Class* #t154 = self::Extension|method(new self::Class::•()) in let final void #t155 = self::Extension|set#field(let final self::Class* #t156 = c in #t156 == null ?{self::Class*} null : self::Extension|method(#t156), #t154) in #t154);
+  self::throws(() → self::Class* => c = let final self::Class* #t157 = self::Extension|method(new self::Class::•()) in let final void #t158 = self::Extension|set#field(let final self::Class* #t159 = c in #t159 == null ?{self::Class*} null : self::Extension|method(#t159), #t157) in #t157);
+  self::throws(() → self::Class* => self::Extension|get#field(self::Extension|method(let final self::Class* #t160 = c in #t160 == null ?{self::Class*} null : self::Extension|get#field(#t160))));
+  self::throws(() → self::Class* => let final self::Class* #t161 = new self::Class::•() in let final void #t162 = self::Extension|set#field(self::Extension|method(let final self::Class* #t163 = c in #t163 == null ?{self::Class*} null : self::Extension|get#field(#t163)), #t161) in #t161);
+  self::throws(() → self::Class* => c = let final self::Class* #t164 = new self::Class::•() in let final void #t165 = self::Extension|set#field(self::Extension|method(let final self::Class* #t166 = c in #t166 == null ?{self::Class*} null : self::Extension|get#field(#t166)), #t164) in #t164);
+  self::throws(() → self::Class* => self::Extension|method(self::Extension|method(let final self::Class* #t167 = c in #t167 == null ?{self::Class*} null : self::Extension|get#field(#t167))));
+  let final self::Class* #t168 = c in #t168 == null ?{self::Class*} null : self::Extension|set#field(#t168, self::Extension|get#field(self::Extension|method(new self::Class::•())));
+  c = let final self::Class* #t169 = c in #t169 == null ?{self::Class*} null : let final self::Class* #t170 = self::Extension|get#field(self::Extension|method(new self::Class::•())) in let final void #t171 = self::Extension|set#field(#t169, #t170) in #t170;
+  let final self::Class* #t172 = c in #t172 == null ?{self::Class*} null : self::Extension|set#field(#t172, let final self::Class* #t173 = new self::Class::•() in let final void #t174 = self::Extension|set#field(self::Extension|method(new self::Class::•()), #t173) in #t173);
+  c = let final self::Class* #t175 = c in #t175 == null ?{self::Class*} null : let final self::Class* #t176 = let final self::Class* #t177 = new self::Class::•() in let final void #t178 = self::Extension|set#field(self::Extension|method(new self::Class::•()), #t177) in #t177 in let final void #t179 = self::Extension|set#field(#t175, #t176) in #t176;
+  let final self::Class* #t180 = c in #t180 == null ?{self::Class*} null : self::Extension|set#field(#t180, self::Extension|method(self::Extension|method(new self::Class::•())));
+  c = let final self::Class* #t181 = c in #t181 == null ?{self::Class*} null : let final self::Class* #t182 = self::Extension|method(self::Extension|method(new self::Class::•())) in let final void #t183 = self::Extension|set#field(#t181, #t182) in #t182;
+  self::throws(() → self::Class* => self::Extension|get#field(self::Extension|method(let final self::Class* #t184 = c in #t184 == null ?{self::Class*} null : self::Extension|method(#t184))));
+  self::throws(() → self::Class* => let final self::Class* #t185 = new self::Class::•() in let final void #t186 = self::Extension|set#field(self::Extension|method(let final self::Class* #t187 = c in #t187 == null ?{self::Class*} null : self::Extension|method(#t187)), #t185) in #t185);
+  self::throws(() → self::Class* => self::Extension|method(self::Extension|method(let final self::Class* #t188 = c in #t188 == null ?{self::Class*} null : self::Extension|method(#t188))));
+  let final self::Class* #t189 = let final self::Class* #t190 = c in #t190 == null ?{self::Class*} null : self::Extension|method(#t190) in #t189 == null ?{self::Class*} null : self::Extension|method(#t189);
+}
+static method indexAccess(self::Class* c) → void {
+  self::throws(() → self::Class* => self::Extension|[](let final self::Class* #t191 = c in #t191 == null ?{self::Class*} null : self::Extension|get#field(#t191), c));
+  self::throws(() → self::Class* => let final self::Class* #t192 = let final self::Class* #t193 = c in #t193 == null ?{self::Class*} null : self::Extension|get#field(#t193) in let final self::Class* #t194 = c in let final self::Class* #t195 = new self::Class::•() in let final void #t196 = self::Extension|[]=(#t192, #t194, #t195) in #t195);
+  self::throws(() → self::Class* => c = let final self::Class* #t197 = let final self::Class* #t198 = c in #t198 == null ?{self::Class*} null : self::Extension|get#field(#t198) in let final self::Class* #t199 = c in let final self::Class* #t200 = new self::Class::•() in let final void #t201 = self::Extension|[]=(#t197, #t199, #t200) in #t200);
+  self::throws(() → self::Class* => self::Extension|method(self::Extension|[](let final self::Class* #t202 = c in #t202 == null ?{self::Class*} null : self::Extension|get#field(#t202), c)));
+  self::throws(() → self::Class* => let final self::Class* #t203 = let final self::Class* #t204 = c in #t204 == null ?{self::Class*} null : self::Extension|get#field(#t204) in let final self::Class* #t205 = c in let final self::Class* #t206 = self::Extension|+(self::Extension|[](#t203, #t205), 0) in let final void #t207 = self::Extension|[]=(#t203, #t205, #t206) in #t206);
+  self::throws(() → self::Class* => c = let final self::Class* #t208 = let final self::Class* #t209 = c in #t209 == null ?{self::Class*} null : self::Extension|get#field(#t209) in let final self::Class* #t210 = c in let final self::Class* #t211 = self::Extension|+(self::Extension|[](#t208, #t210), 0) in let final void #t212 = self::Extension|[]=(#t208, #t210, #t211) in #t211);
+  self::throws(() → self::Class* => let final self::Class* #t213 = let final self::Class* #t214 = c in #t214 == null ?{self::Class*} null : self::Extension|get#field(#t214) in let final self::Class* #t215 = c in let final self::Class* #t216 = self::Extension|[](#t213, #t215) in let final void #t217 = self::Extension|[]=(#t213, #t215, self::Extension|+(#t216, 1)) in #t216);
+  self::throws(() → self::Class* => c = let final self::Class* #t218 = let final self::Class* #t219 = c in #t219 == null ?{self::Class*} null : self::Extension|get#field(#t219) in let final self::Class* #t220 = c in let final self::Class* #t221 = self::Extension|[](#t218, #t220) in let final void #t222 = self::Extension|[]=(#t218, #t220, self::Extension|+(#t221, 1)) in #t221);
+  self::throws(() → self::Class* => let final self::Class* #t223 = let final self::Class* #t224 = c in #t224 == null ?{self::Class*} null : self::Extension|get#field(#t224) in let final self::Class* #t225 = c in let final self::Class* #t226 = self::Extension|+(self::Extension|[](#t223, #t225), 1) in let final void #t227 = self::Extension|[]=(#t223, #t225, #t226) in #t226);
+  self::throws(() → self::Class* => c = let final self::Class* #t228 = let final self::Class* #t229 = c in #t229 == null ?{self::Class*} null : self::Extension|get#field(#t229) in let final self::Class* #t230 = c in let final self::Class* #t231 = self::Extension|+(self::Extension|[](#t228, #t230), 1) in let final void #t232 = self::Extension|[]=(#t228, #t230, #t231) in #t231);
+  self::throws(() → self::Class* => self::Extension|[](self::Extension|[](let final self::Class* #t233 = c in #t233 == null ?{self::Class*} null : self::Extension|get#field(#t233), c), c));
+  self::throws(() → self::Class* => let final self::Class* #t234 = self::Extension|[](let final self::Class* #t235 = c in #t235 == null ?{self::Class*} null : self::Extension|get#field(#t235), c) in let final self::Class* #t236 = c in let final self::Class* #t237 = new self::Class::•() in let final void #t238 = self::Extension|[]=(#t234, #t236, #t237) in #t237);
+  self::throws(() → self::Class* => c = let final self::Class* #t239 = self::Extension|[](let final self::Class* #t240 = c in #t240 == null ?{self::Class*} null : self::Extension|get#field(#t240), c) in let final self::Class* #t241 = c in let final self::Class* #t242 = new self::Class::•() in let final void #t243 = self::Extension|[]=(#t239, #t241, #t242) in #t242);
+  self::throws(() → self::Class* => self::Extension|method(self::Extension|[](self::Extension|[](let final self::Class* #t244 = c in #t244 == null ?{self::Class*} null : self::Extension|get#field(#t244), c), c)));
+  self::throws(() → self::Class* => let final self::Class* #t245 = self::Extension|[](let final self::Class* #t246 = c in #t246 == null ?{self::Class*} null : self::Extension|get#field(#t246), c) in let final self::Class* #t247 = c in let final self::Class* #t248 = self::Extension|+(self::Extension|[](#t245, #t247), 0) in let final void #t249 = self::Extension|[]=(#t245, #t247, #t248) in #t248);
+  self::throws(() → self::Class* => c = let final self::Class* #t250 = self::Extension|[](let final self::Class* #t251 = c in #t251 == null ?{self::Class*} null : self::Extension|get#field(#t251), c) in let final self::Class* #t252 = c in let final self::Class* #t253 = self::Extension|+(self::Extension|[](#t250, #t252), 0) in let final void #t254 = self::Extension|[]=(#t250, #t252, #t253) in #t253);
+  self::throws(() → self::Class* => let final self::Class* #t255 = self::Extension|[](let final self::Class* #t256 = c in #t256 == null ?{self::Class*} null : self::Extension|get#field(#t256), c) in let final self::Class* #t257 = c in let final self::Class* #t258 = self::Extension|[](#t255, #t257) in let final void #t259 = self::Extension|[]=(#t255, #t257, self::Extension|+(#t258, 1)) in #t258);
+  self::throws(() → self::Class* => c = let final self::Class* #t260 = self::Extension|[](let final self::Class* #t261 = c in #t261 == null ?{self::Class*} null : self::Extension|get#field(#t261), c) in let final self::Class* #t262 = c in let final self::Class* #t263 = self::Extension|[](#t260, #t262) in let final void #t264 = self::Extension|[]=(#t260, #t262, self::Extension|+(#t263, 1)) in #t263);
+  self::throws(() → self::Class* => let final self::Class* #t265 = self::Extension|[](let final self::Class* #t266 = c in #t266 == null ?{self::Class*} null : self::Extension|get#field(#t266), c) in let final self::Class* #t267 = c in let final self::Class* #t268 = self::Extension|+(self::Extension|[](#t265, #t267), 1) in let final void #t269 = self::Extension|[]=(#t265, #t267, #t268) in #t268);
+  self::throws(() → self::Class* => c = let final self::Class* #t270 = self::Extension|[](let final self::Class* #t271 = c in #t271 == null ?{self::Class*} null : self::Extension|get#field(#t271), c) in let final self::Class* #t272 = c in let final self::Class* #t273 = self::Extension|+(self::Extension|[](#t270, #t272), 1) in let final void #t274 = self::Extension|[]=(#t270, #t272, #t273) in #t273);
+}
+static method operatorAccess(self::Class* c) → void {
+  self::throws(() → self::Class* => self::Extension|+(let final self::Class* #t275 = c in #t275 == null ?{self::Class*} null : self::Extension|get#field(#t275), 0));
+  self::throws(() → self::Class* => self::Extension|unary-(let final self::Class* #t276 = c in #t276 == null ?{self::Class*} null : self::Extension|get#field(#t276)));
+  let final self::Class* #t277 = c in #t277 == null ?{self::Class*} null : self::Extension|set#field(#t277, self::Extension|+(self::Extension|get#field(#t277), 0));
+  c = let final self::Class* #t278 = c in #t278 == null ?{self::Class*} null : let final self::Class* #t279 = self::Extension|+(self::Extension|get#field(#t278), 0) in let final void #t280 = self::Extension|set#field(#t278, #t279) in #t279;
+  self::throws(() → self::Class* => let final self::Class* #t281 = let final self::Class* #t282 = c in #t282 == null ?{self::Class*} null : self::Extension|get#field(#t282) in let final self::Class* #t283 = self::Extension|+(self::Extension|get#field(#t281), 0) in let final void #t284 = self::Extension|set#field(#t281, #t283) in #t283);
+  self::throws(() → self::Class* => c = let final self::Class* #t285 = let final self::Class* #t286 = c in #t286 == null ?{self::Class*} null : self::Extension|get#field(#t286) in let final self::Class* #t287 = self::Extension|+(self::Extension|get#field(#t285), 0) in let final void #t288 = self::Extension|set#field(#t285, #t287) in #t287);
+  let final self::Class* #t289 = c in #t289 == null ?{self::Class*} null : self::Extension|set#field(#t289, self::Extension|+(self::Extension|get#field(#t289), 1));
+  c = let final self::Class* #t290 = c in #t290 == null ?{self::Class*} null : let final self::Class* #t291 = self::Extension|get#field(#t290) in let final void #t292 = self::Extension|set#field(#t290, self::Extension|+(#t291, 1)) in #t291;
+  let final self::Class* #t293 = c in #t293 == null ?{self::Class*} null : let final self::Class* #t294 = self::Extension|+(self::Extension|get#field(#t293), 1) in let final void #t295 = self::Extension|set#field(#t293, #t294) in #t294;
+  c = let final self::Class* #t296 = c in #t296 == null ?{self::Class*} null : let final self::Class* #t297 = self::Extension|+(self::Extension|get#field(#t296), 1) in let final void #t298 = self::Extension|set#field(#t296, #t297) in #t297;
+}
+static method ifNull(self::Class* c) → void {
+  let final self::Class* #t299 = c in #t299 == null ?{self::Class*} null : self::Extension|get#field(#t299) == null ?{self::Class*} self::Extension|set#field(#t299, c) : null;
+  c = let final self::Class* #t300 = c in #t300 == null ?{self::Class*} null : let final self::Class* #t301 = self::Extension|get#field(#t300) in #t301 == null ?{self::Class*} let final self::Class* #t302 = c in let final void #t303 = self::Extension|set#field(#t300, #t302) in #t302 : #t301;
+  self::throws(() → self::Class* => let final self::Class* #t304 = let final self::Class* #t305 = c in #t305 == null ?{self::Class*} null : self::Extension|get#field(#t305) in let final self::Class* #t306 = self::Extension|get#field(#t304) in #t306 == null ?{self::Class*} let final self::Class* #t307 = c in let final void #t308 = self::Extension|set#field(#t304, #t307) in #t307 : #t306);
+  self::throws(() → self::Class* => c = let final self::Class* #t309 = let final self::Class* #t310 = c in #t310 == null ?{self::Class*} null : self::Extension|get#field(#t310) in let final self::Class* #t311 = self::Extension|get#field(#t309) in #t311 == null ?{self::Class*} let final self::Class* #t312 = c in let final void #t313 = self::Extension|set#field(#t309, #t312) in #t312 : #t311);
+  self::throws(() → self::Class* => let final self::Class* #t314 = let final self::Class* #t315 = c in #t315 == null ?{self::Class*} null : self::Extension|get#field(#t315) in let final self::Class* #t316 = c in let final self::Class* #t317 = self::Extension|[](#t314, #t316) in #t317 == null ?{self::Class*} let final self::Class* #t318 = c in let final void #t319 = self::Extension|[]=(#t314, #t316, #t318) in #t318 : #t317);
+  self::throws(() → self::Class* => c = let final self::Class* #t320 = let final self::Class* #t321 = c in #t321 == null ?{self::Class*} null : self::Extension|get#field(#t321) in let final self::Class* #t322 = c in let final self::Class* #t323 = self::Extension|[](#t320, #t322) in #t323 == null ?{self::Class*} let final self::Class* #t324 = c in let final void #t325 = self::Extension|[]=(#t320, #t322, #t324) in #t324 : #t323);
+}
+static method throws(() →* void f) → void {
+  try {
+    f(){() →* void};
+  }
+  on dynamic catch(final dynamic _) {
+    return;
+  }
+  throw "Expected exception.";
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/nsm_from_opt_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/nsm_from_opt_in.dart.weak.modular.expect
new file mode 100644
index 0000000..9262574
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/nsm_from_opt_in.dart.weak.modular.expect
@@ -0,0 +1,113 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "nsm_from_opt_in_lib.dart" as nsm;
+
+import "org-dartlang-testcase:///nsm_from_opt_in_lib.dart";
+
+abstract class A2 extends core::Object implements nsm::A {
+  synthetic constructor •() → self::A2*
+    : super core::Object::•()
+    ;
+  @#C1
+  method noSuchMethod(core::Invocation* invocation) → dynamic {
+    return super.{core::Object::noSuchMethod}(invocation);
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature method method(core::int* i) → core::int*; -> nsm::A::method
+  abstract member-signature method genericMethod1<T extends core::Object* = dynamic>(self::A2::genericMethod1::T* t) → self::A2::genericMethod1::T*; -> nsm::A::genericMethod1
+  abstract member-signature method genericMethod2<T extends core::Object*>(self::A2::genericMethod2::T* t) → self::A2::genericMethod2::T*; -> nsm::A::genericMethod2
+  abstract member-signature method genericMethod3<T extends core::Object*>(self::A2::genericMethod3::T* t) → self::A2::genericMethod3::T*; -> nsm::A::genericMethod3
+}
+abstract class B2 extends nsm::A implements self::C2 {
+  synthetic constructor •() → self::B2*
+    : super nsm::A::•()
+    ;
+  @#C1
+  method noSuchMethod(core::Invocation* invocation) → dynamic {
+    return super.{core::Object::noSuchMethod}(invocation);
+  }
+  abstract member-signature method method(core::int* i, {dynamic optional = #C2}) → core::int*; -> self::C2::method
+  abstract member-signature method genericMethod1<T extends core::Object* = dynamic>(self::B2::genericMethod1::T* t) → self::B2::genericMethod1::T*; -> nsm::A::genericMethod1
+  abstract member-signature method genericMethod2<T extends core::Object*>(self::B2::genericMethod2::T* t) → self::B2::genericMethod2::T*; -> nsm::A::genericMethod2
+  abstract member-signature method genericMethod3<T extends core::Object*>(self::B2::genericMethod3::T* t) → self::B2::genericMethod3::T*; -> nsm::A::genericMethod3
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C2 extends core::Object {
+  synthetic constructor •() → self::C2*
+    : super core::Object::•()
+    ;
+  abstract method method(core::int* i, {dynamic optional = #C2}) → core::int*;
+  abstract method genericMethod1<T extends core::Object* = dynamic>(self::C2::genericMethod1::T* t) → self::C2::genericMethod1::T*;
+  abstract method genericMethod2<T extends core::Object*>(self::C2::genericMethod2::T* t) → self::C2::genericMethod2::T*;
+  abstract method genericMethod3<T extends core::Object*>(self::C2::genericMethod3::T* t) → self::C2::genericMethod3::T*;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as nsm;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → nsm::A
+    : super core::Object::•()
+    ;
+  method method(core::int? i) → core::int
+    return let final core::int? #t1 = i in #t1 == null ?{core::int} 0 : #t1{core::int};
+  method genericMethod1<T extends core::Object? = dynamic>(nsm::A::genericMethod1::T% t) → nsm::A::genericMethod1::T%
+    return t;
+  method genericMethod2<T extends core::Object?>(nsm::A::genericMethod2::T% t) → nsm::A::genericMethod2::T%
+    return t;
+  method genericMethod3<T extends core::Object>(nsm::A::genericMethod3::T t) → nsm::A::genericMethod3::T
+    return t;
+}
+abstract class B1 extends nsm::A implements nsm::C1 {
+  synthetic constructor •() → nsm::B1
+    : super nsm::A::•()
+    ;
+  @#C1
+  method noSuchMethod(core::Invocation invocation) → dynamic {
+    return super.{core::Object::noSuchMethod}(invocation);
+  }
+  abstract member-signature method method(core::int? i, {dynamic optional = #C2}) → core::int; -> nsm::C1::method
+}
+abstract class C1 extends core::Object {
+  synthetic constructor •() → nsm::C1
+    : super core::Object::•()
+    ;
+  abstract method method(core::int? i, {dynamic optional = #C2}) → core::int;
+  abstract method genericMethod1<T extends core::Object? = dynamic>(nsm::C1::genericMethod1::T% t) → nsm::C1::genericMethod1::T%;
+  abstract method genericMethod2<T extends core::Object?>(nsm::C1::genericMethod2::T% t) → nsm::C1::genericMethod2::T%;
+  abstract method genericMethod3<T extends core::Object>(nsm::C1::genericMethod3::T t) → nsm::C1::genericMethod3::T;
+}
+
+constants  {
+  #C1 = core::_Override {}
+  #C2 = null
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/null_safety_invalid_language_version.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/null_safety_invalid_language_version.dart.weak.modular.expect
new file mode 100644
index 0000000..46b2806
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/null_safety_invalid_language_version.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/null_safety_invalid_language_version.dart:7:4: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+// int? i;
+//    ^
+// pkg/front_end/testcases/nnbd_mixed/null_safety_invalid_language_version.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.7
+// ^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static field core::int? i;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/nullable_extension_on_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/nullable_extension_on_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..f4ebaa4
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/nullable_extension_on_opt_out.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "nullable_extension_on_opt_out_lib.dart" as nul;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///nullable_extension_on_opt_out_lib.dart";
+
+extension _extension#0 on nul::A? {
+  get text = self::_extension#0|get#text;
+}
+static method _extension#0|get#text(lowered final nul::A? #this) → core::String
+  return "Lily was here";
+static method main() → void {
+  nul::A? a = null;
+  self::expect("Lily was here", self::_extension#0|get#text(a));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+
+library;
+import self as nul;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::String* text = "";
+  synthetic constructor •() → nul::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/object_bound_factory/main.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/object_bound_factory/main.dart.weak.modular.expect
new file mode 100644
index 0000000..e605bd9
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/object_bound_factory/main.dart.weak.modular.expect
@@ -0,0 +1,154 @@
+library;
+import self as self;
+import "opt_in_lib.dart" as opt;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///opt_in_lib.dart";
+
+static method main() → dynamic {
+  new opt::Class1::_<core::Object*>();
+  new opt::Class1::_<core::Object*>();
+  #C1;
+  opt::Class1::fact<core::Object*>();
+  new opt::Class2::_<core::Object*>();
+  new opt::Class2::_<core::Object*>();
+  #C2;
+  opt::Class2::fact<core::Object*>();
+  new opt::Class3::_<core::String*>();
+  new opt::Class3::_<core::String*>();
+  #C3;
+  opt::Class3::fact<core::String*>();
+  new opt::Class4::_<dynamic>();
+  new opt::Class4::_<dynamic>();
+  #C4;
+  opt::Class4::fact<dynamic>();
+  new opt::Class5::_<dynamic>();
+  new opt::Class5::_<dynamic>();
+  #C5;
+  opt::Class5::fact<dynamic>();
+  opt::testOptIn();
+}
+
+library /*isNonNullableByDefault*/;
+import self as opt;
+import "dart:core" as core;
+
+class Class1<T extends core::Object?> extends core::Object /*hasConstConstructor*/  {
+  static final field dynamic _redirecting# = <dynamic>[#C6, #C7]/*isLegacy*/;
+  const constructor _() → opt::Class1<opt::Class1::T%>
+    : super core::Object::•()
+    ;
+  static factory redirect<T extends core::Object?>() → opt::Class1<opt::Class1::redirect::T%>
+    return new opt::Class1::_<opt::Class1::redirect::T%>();
+  static factory constRedirect<T extends core::Object?>() → opt::Class1<opt::Class1::constRedirect::T%>
+    return new opt::Class1::_<opt::Class1::constRedirect::T%>();
+  static factory fact<T extends core::Object?>() → opt::Class1<opt::Class1::fact::T%>
+    return new opt::Class1::_<opt::Class1::fact::T%>();
+}
+class Class2<T extends core::Object> extends core::Object /*hasConstConstructor*/  {
+  static final field dynamic _redirecting# = <dynamic>[#C8, #C9]/*isLegacy*/;
+  const constructor _() → opt::Class2<opt::Class2::T>
+    : super core::Object::•()
+    ;
+  static factory redirect<T extends core::Object>() → opt::Class2<opt::Class2::redirect::T>
+    return new opt::Class2::_<opt::Class2::redirect::T>();
+  static factory constRedirect<T extends core::Object>() → opt::Class2<opt::Class2::constRedirect::T>
+    return new opt::Class2::_<opt::Class2::constRedirect::T>();
+  static factory fact<T extends core::Object>() → opt::Class2<opt::Class2::fact::T>
+    return new opt::Class2::_<opt::Class2::fact::T>();
+}
+class Class3<T extends core::String> extends core::Object /*hasConstConstructor*/  {
+  static final field dynamic _redirecting# = <dynamic>[#C10, #C11]/*isLegacy*/;
+  const constructor _() → opt::Class3<opt::Class3::T>
+    : super core::Object::•()
+    ;
+  static factory redirect<T extends core::String>() → opt::Class3<opt::Class3::redirect::T>
+    return new opt::Class3::_<opt::Class3::redirect::T>();
+  static factory constRedirect<T extends core::String>() → opt::Class3<opt::Class3::constRedirect::T>
+    return new opt::Class3::_<opt::Class3::constRedirect::T>();
+  static factory fact<T extends core::String>() → opt::Class3<opt::Class3::fact::T>
+    return new opt::Class3::_<opt::Class3::fact::T>();
+}
+class Class4<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
+  static final field dynamic _redirecting# = <dynamic>[#C12, #C13]/*isLegacy*/;
+  const constructor _() → opt::Class4<opt::Class4::T%>
+    : super core::Object::•()
+    ;
+  static factory redirect<T extends core::Object? = dynamic>() → opt::Class4<opt::Class4::redirect::T%>
+    return new opt::Class4::_<opt::Class4::redirect::T%>();
+  static factory constRedirect<T extends core::Object? = dynamic>() → opt::Class4<opt::Class4::constRedirect::T%>
+    return new opt::Class4::_<opt::Class4::constRedirect::T%>();
+  static factory fact<T extends core::Object? = dynamic>() → opt::Class4<opt::Class4::fact::T%>
+    return new opt::Class4::_<opt::Class4::fact::T%>();
+}
+class Class5<T extends dynamic> extends core::Object /*hasConstConstructor*/  {
+  static final field dynamic _redirecting# = <dynamic>[#C14, #C15]/*isLegacy*/;
+  const constructor _() → opt::Class5<opt::Class5::T%>
+    : super core::Object::•()
+    ;
+  static factory redirect<T extends dynamic>() → opt::Class5<opt::Class5::redirect::T%>
+    return new opt::Class5::_<opt::Class5::redirect::T%>();
+  static factory constRedirect<T extends dynamic>() → opt::Class5<opt::Class5::constRedirect::T%>
+    return new opt::Class5::_<opt::Class5::constRedirect::T%>();
+  static factory fact<T extends dynamic>() → opt::Class5<opt::Class5::fact::T%>
+    return new opt::Class5::_<opt::Class5::fact::T%>();
+}
+static method testOptIn() → dynamic {
+  new opt::Class1::_<core::Object?>();
+  new opt::Class1::_<core::Object?>();
+  #C16;
+  opt::Class1::fact<core::Object?>();
+  new opt::Class2::_<core::Object>();
+  new opt::Class2::_<core::Object>();
+  #C2;
+  opt::Class2::fact<core::Object>();
+  new opt::Class3::_<core::String>();
+  new opt::Class3::_<core::String>();
+  #C3;
+  opt::Class3::fact<core::String>();
+  new opt::Class4::_<dynamic>();
+  new opt::Class4::_<dynamic>();
+  #C4;
+  opt::Class4::fact<dynamic>();
+  new opt::Class5::_<dynamic>();
+  new opt::Class5::_<dynamic>();
+  #C5;
+  opt::Class5::fact<dynamic>();
+}
+
+constants  {
+  #C1 = opt::Class1<core::Object*> {}
+  #C2 = opt::Class2<core::Object*> {}
+  #C3 = opt::Class3<core::String*> {}
+  #C4 = opt::Class4<dynamic> {}
+  #C5 = opt::Class5<dynamic> {}
+  #C6 = constructor-tearoff opt::Class1::redirect
+  #C7 = constructor-tearoff opt::Class1::constRedirect
+  #C8 = constructor-tearoff opt::Class2::redirect
+  #C9 = constructor-tearoff opt::Class2::constRedirect
+  #C10 = constructor-tearoff opt::Class3::redirect
+  #C11 = constructor-tearoff opt::Class3::constRedirect
+  #C12 = constructor-tearoff opt::Class4::redirect
+  #C13 = constructor-tearoff opt::Class4::constRedirect
+  #C14 = constructor-tearoff opt::Class5::redirect
+  #C15 = constructor-tearoff opt::Class5::constRedirect
+  #C16 = opt::Class1<core::Object?> {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///main.dart:
+- Class1._ (from org-dartlang-testcase:///opt_in_lib.dart:10:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Class2._ (from org-dartlang-testcase:///opt_in_lib.dart:18:9)
+- Class3._ (from org-dartlang-testcase:///opt_in_lib.dart:26:9)
+- Class4._ (from org-dartlang-testcase:///opt_in_lib.dart:34:9)
+- Class5._ (from org-dartlang-testcase:///opt_in_lib.dart:42:9)
+
+org-dartlang-testcase:///opt_in_lib.dart:
+- Class1._ (from org-dartlang-testcase:///opt_in_lib.dart:10:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- Class2._ (from org-dartlang-testcase:///opt_in_lib.dart:18:9)
+- Class3._ (from org-dartlang-testcase:///opt_in_lib.dart:26:9)
+- Class4._ (from org-dartlang-testcase:///opt_in_lib.dart:34:9)
+- Class5._ (from org-dartlang-testcase:///opt_in_lib.dart:42:9)
diff --git a/pkg/front_end/testcases/nnbd_mixed/object_bound_redirecting_factory/main.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/object_bound_redirecting_factory/main.dart.weak.modular.expect
new file mode 100644
index 0000000..342dcae
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/object_bound_redirecting_factory/main.dart.weak.modular.expect
@@ -0,0 +1,101 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "opt_in_lib.dart" as opt;
+
+import "org-dartlang-testcase:///opt_in_lib.dart";
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class XToken extends opt::Token<core::Object*> /*hasConstConstructor*/  {
+  const constructor •() → self::XToken*
+    : super opt::Token::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static const field core::List<opt::P<core::Object*>*>* list = #C5;
+static const field opt::M* m = #C6;
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as opt;
+import "dart:core" as core;
+
+class P<T extends core::Object> extends core::Object /*hasConstConstructor*/  {
+  final field core::Object token;
+  const constructor _(core::Object token) → opt::P<opt::P::T>
+    : opt::P::token = token, super core::Object::•()
+    ;
+}
+class CP<T extends core::Object> extends opt::P<opt::CP::T> /*hasConstConstructor*/  {
+  static final field dynamic _redirecting# = <dynamic>[#C7]/*isLegacy*/;
+  const constructor _(core::Object token) → opt::CP<opt::CP::T>
+    : super opt::P::_(token)
+    ;
+  static factory •<T extends core::Object>(core::Type type) → opt::CP<opt::CP::•::T>
+    return new opt::CP::_<opt::CP::•::T>(type);
+}
+class Token<T extends core::Object> extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → opt::Token<opt::Token::T>
+    : super core::Object::•()
+    ;
+}
+class VP<T extends core::Object> extends opt::P<opt::VP::T> /*hasConstConstructor*/  {
+  static final field dynamic _redirecting# = <dynamic>[#C8]/*isLegacy*/;
+  const constructor _(core::Object token, opt::VP::T useValue) → opt::VP<opt::VP::T>
+    : super opt::P::_(token)
+    ;
+  static factory forToken<T extends core::Object>(opt::Token<opt::VP::forToken::T> token, opt::VP::forToken::T useValue) → opt::VP<opt::VP::forToken::T>
+    return new opt::VP::_<opt::VP::forToken::T>(token, useValue);
+}
+class M extends core::Object /*hasConstConstructor*/  {
+  final field core::List<opt::P<core::Object>> list;
+  const constructor •({core::List<opt::P<core::Object>> list = #C9}) → opt::M
+    : opt::M::list = list, super core::Object::•()
+    ;
+}
+
+constants  {
+  #C1 = TypeLiteralConstant(self::Class*)
+  #C2 = opt::CP<core::Object*> {token:#C1}
+  #C3 = self::XToken {}
+  #C4 = opt::VP<core::Object*> {token:#C3}
+  #C5 = <opt::P<core::Object*>*>[#C2, #C4]
+  #C6 = opt::M {list:#C5}
+  #C7 = constructor-tearoff opt::CP::•
+  #C8 = constructor-tearoff opt::VP::forToken
+  #C9 = <opt::P<core::Object*>*>[]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///main.dart:
+- CP._ (from org-dartlang-testcase:///opt_in_lib.dart:14:9)
+- P._ (from org-dartlang-testcase:///opt_in_lib.dart:8:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- XToken. (from org-dartlang-testcase:///main.dart:12:9)
+- Token. (from org-dartlang-testcase:///opt_in_lib.dart:18:9)
+- VP._ (from org-dartlang-testcase:///opt_in_lib.dart:27:9)
+- M. (from org-dartlang-testcase:///opt_in_lib.dart:36:9)
diff --git a/pkg/front_end/testcases/nnbd_mixed/opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..6e0d3ce
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/opt_out.dart.weak.modular.expect
@@ -0,0 +1,181 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/opt_out.dart:18:11: Error: Can't create typedef from nullable type.
+// typedef F = void Function()?;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///opt_out_lib.dart";
+
+typedef F = invalid-type;
+class A<T extends core::Object? = dynamic> extends core::Object {
+  late field core::int field = 42;
+  synthetic constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+}
+class B extends self::A<core::String?> {
+  synthetic constructor •() → self::B
+    : super self::A::•()
+    ;
+}
+static field core::List<core::String?> l = <core::String?>[];
+static field core::String? s = null;
+static field core::String t = self::s!;
+late static field core::int field = 42;
+static method method(() →? void f, {required core::int a = #C1}) → void {}
+static method main() → dynamic {}
+static method noErrors() → dynamic {
+  late core::int local = 42;
+  core::String? s = null;
+  dynamic c;
+  let final dynamic #t1 = c in #t1 == null ?{dynamic} null : block {
+    #t1{dynamic}.f;
+  } =>#t1;
+  let final dynamic #t2 = c in #t2 == null ?{dynamic} null : #t2{dynamic}.[](0);
+}
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:18:25: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+// class B extends A<String?> {}
+//                         ^
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.5
+// ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:20:28: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+// typedef F = void Function()?;
+//                            ^
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.5
+// ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:22:12: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+// List<String?> l = [];
+//            ^
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.5
+// ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:23:7: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+// String? s = null;
+//       ^
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.5
+// ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:28:21: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+// void method(void f()?, {int a}) {}
+//                     ^
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.5
+// ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:24:10: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+// var t = s!;
+//          ^
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.5
+// ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:32:14: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+//   List<String?> l = null;
+//              ^
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.5
+// ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:33:9: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+//   String? s = null;
+//         ^
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.5
+// ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:34:12: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+//   var t = s!;
+//            ^
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.5
+// ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:36:6: Error: Expected an identifier, but got '.'.
+// Try inserting an identifier before '.'.
+//   c?..f;
+//      ^
+//
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:36:6: Error: Expected an identifier, but got ''.
+// Try inserting an identifier before ''.
+//   c?..f;
+//      ^
+//
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:37:5: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+//   c?[0];
+//     ^
+// pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:5:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.5
+// ^^^^^^^^^^^^
+//
+import self as self2;
+import "dart:core" as core;
+
+typedef F = () →? void;
+class A<T extends core::Object* = dynamic> extends core::Object {
+  field core::int* field = 42;
+  synthetic constructor •() → self2::A<self2::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self2::A<core::String*> {
+  synthetic constructor •() → self2::B*
+    : super self2::A::•()
+    ;
+}
+static field core::List<core::String?>* l = <core::String*>[];
+static field core::String? s = null;
+static field core::String* t = self2::s!;
+static field core::int* field = 42;
+static method method(() →* void f, {core::int* a = #C1}) → void {}
+static method errors() → dynamic {
+  core::int* local = 42;
+  core::List<core::String?>* l = null;
+  core::String? s = null;
+  core::String* t = s!;
+  dynamic c;
+  invalid-expression "pkg/front_end/testcases/nnbd_mixed/opt_out_lib.dart:36:6: Error: Expected an identifier, but got ''.
+Try inserting an identifier before ''.
+  c?..f;
+     ^"{<invalid>}.f;
+  let final dynamic #t3 = c in #t3 == null ?{dynamic} null : #t3{dynamic}.[](0);
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/regress_null_aware.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/regress_null_aware.dart.weak.modular.expect
new file mode 100644
index 0000000..54456fa
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/regress_null_aware.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+class Class extends core::Object {
+  field core::Map<core::String*, core::Set<core::String*>*>* map = null;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  method method(core::String* node, core::Set<core::String*>* set) → core::List<core::String*>*
+    return set.{core::Set::add}(node){(core::String*) →* core::bool*} ?{core::List<core::String*>*} block {
+      final core::List<core::String*>* #t1 = <core::String*>[node];
+      final core::Iterable<core::String*>* #t2 = let final core::Iterable<core::String*>* #t3 = let final core::Set<core::String*>* #t4 = this.{self::Class::map}{core::Map<core::String*, core::Set<core::String*>*>*}.{core::Map::[]}(node){(core::Object*) →* core::Set<core::String*>*} in #t4 == null ?{core::Iterable<core::String*>*} null : #t4.{core::Iterable::expand}<core::String*>((core::String* node) → core::List<core::String*>* => this.{self::Class::method}(node, set){(core::String*, core::Set<core::String*>*) →* core::List<core::String*>*}){((core::String*) →* core::Iterable<core::String*>*) →* core::Iterable<core::String*>*} in #t3 == null ?{core::List<core::String*>*} null : #t3.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<core::String*>*};
+      if(!(#t2 == null))
+        #t1.{core::List::addAll}{Invariant}(#t2){(core::Iterable<core::String*>*) →* void};
+    } =>#t1 : <core::String*>[];
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main(dynamic args) → dynamic {
+  if(false)
+    new self::Class::•().{self::Class::method}("", block {
+      final core::Set<core::String*>* #t5 = col::LinkedHashSet::•<core::String*>();
+    } =>#t5){(core::String*, core::Set<core::String*>*) →* core::List<core::String*>*};
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/required_name_override.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/required_name_override.dart.weak.modular.expect
new file mode 100644
index 0000000..90a553a
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/required_name_override.dart.weak.modular.expect
@@ -0,0 +1,71 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/required_name_override.dart:13:36: Error: The required named parameter 'i' in method 'A.test_default' is not required in overridden method 'B.test_default'.
+//   void test_default({required int? i}) {}
+//                                    ^
+// pkg/front_end/testcases/nnbd_mixed/required_name_override.dart:8:8: Context: This is the overridden method ('test_default').
+//   void test_default({int? i}) {}
+//        ^
+//
+// pkg/front_end/testcases/nnbd_mixed/required_name_override.dart:14:39: Error: The required named parameter 'i' in method 'A.test_nondefault' is not required in overridden method 'B.test_nondefault'.
+//   void test_nondefault({required int? i}) {}
+//                                       ^
+// pkg/front_end/testcases/nnbd_mixed/required_name_override.dart:9:8: Context: This is the overridden method ('test_nondefault').
+//   void test_nondefault({int? i = 1}) {}
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+import "required_name_override_lib.dart" as req;
+
+import "org-dartlang-testcase:///required_name_override_lib.dart";
+
+class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+  method test_default({core::int? i = #C1}) → void {}
+  method test_nondefault({core::int? i = #C2}) → void {}
+}
+class A extends self::B implements req::C {
+  synthetic constructor •() → self::A
+    : super self::B::•()
+    ;
+  method test_default({required core::int? i = #C1}) → void {}
+  method test_nondefault({required core::int? i = #C1}) → void {}
+  method test_legacy({required core::int? i = #C1}) → void {}
+  abstract member-signature operator /*isLegacy*/ ==(dynamic other) → core::bool*; -> core::Object::==
+}
+static method main() → dynamic {
+  new self::A::•().{self::A::test_default}(i: 1){({required i: core::int?}) → void};
+  new self::A::•().{self::A::test_nondefault}(i: 1){({required i: core::int?}) → void};
+  new self::A::•().{self::A::test_legacy}(i: 1){({required i: core::int?}) → void};
+}
+
+library;
+import self as req;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → req::C*
+    : super core::Object::•()
+    ;
+  method test_legacy({core::int* i = #C1}) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+constants  {
+  #C1 = null
+  #C2 = 1
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/required_parameter_mixed_from_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/required_parameter_mixed_from_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..1d47863
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/required_parameter_mixed_from_opt_out.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "required_parameter_mixed_from_opt_out_lib.dart" as req;
+
+import "org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart";
+
+class Super extends core::Object {
+  synthetic constructor •() → self::Super
+    : super core::Object::•()
+    ;
+  method method({required covariant-by-declaration core::int named = #C1}) → void {}
+}
+abstract class _Class&Super&Mixin = self::Super with req::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Super&Mixin
+    : super self::Super::•()
+    ;
+  forwarding-stub method /*isLegacy*/ method({covariant-by-declaration core::int* named = #C1}) → void
+    return super.{req::Mixin::method}(named: named);
+  abstract member-signature operator /*isLegacy*/ ==(dynamic other) → core::bool*; -> core::Object::==
+}
+class Class extends self::_Class&Super&Mixin {
+  synthetic constructor •() → self::Class
+    : super self::_Class&Super&Mixin::•()
+    ;
+}
+class SubClass extends self::Class {
+  synthetic constructor •() → self::SubClass
+    : super self::Class::•()
+    ;
+  method method({required covariant-by-declaration core::int named = #C1}) → void {}
+}
+static method main() → dynamic {}
+
+library;
+import self as req;
+import "dart:core" as core;
+
+abstract class Mixin extends core::Object /*isMixinDeclaration*/  {
+  method method({core::int* named = #C1}) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/sink_hierarchy.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/sink_hierarchy.dart.weak.modular.expect
new file mode 100644
index 0000000..763dc92
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/sink_hierarchy.dart.weak.modular.expect
@@ -0,0 +1,70 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+abstract class Sink<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Sink<self::Sink::T*>*
+    : super core::Object::•()
+    ;
+  abstract method close() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class EventSink<T extends core::Object* = dynamic> extends core::Object implements self::Sink<self::EventSink::T*> {
+  synthetic constructor •() → self::EventSink<self::EventSink::T*>*
+    : super core::Object::•()
+    ;
+  abstract method close() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class StreamConsumer<S extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::StreamConsumer<self::StreamConsumer::S*>*
+    : super core::Object::•()
+    ;
+  abstract method close() → asy::Future<dynamic>*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class StreamSink<S extends core::Object* = dynamic> extends core::Object implements self::EventSink<self::StreamSink::S*>, self::StreamConsumer<self::StreamSink::S*> {
+  synthetic constructor •() → self::StreamSink<self::StreamSink::S*>*
+    : super core::Object::•()
+    ;
+  abstract method close() → asy::Future<dynamic>*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nnbd_mixed/super_access/main.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/super_access/main.dart.weak.modular.expect
new file mode 100644
index 0000000..864208b
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/super_access/main.dart.weak.modular.expect
@@ -0,0 +1,95 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "main_lib1.dart" as mai;
+import "main_lib2.dart" as mai2;
+
+import "org-dartlang-testcase:///main_lib1.dart";
+import "org-dartlang-testcase:///main_lib2.dart";
+
+abstract class _Class&Object&Mixin1<T extends core::Object* = dynamic> = core::Object with mai::Mixin1<self::_Class&Object&Mixin1::T*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Class&Object&Mixin1<self::_Class&Object&Mixin1::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Class&Object&Mixin1&Mixin2<T extends core::Object* = dynamic> = self::_Class&Object&Mixin1<self::_Class&Object&Mixin1&Mixin2::T*> with mai::Mixin2<self::_Class&Object&Mixin1&Mixin2::T*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Object&Mixin1&Mixin2<self::_Class&Object&Mixin1&Mixin2::T*>*
+    : super self::_Class&Object&Mixin1::•()
+    ;
+  mixin-super-stub get field() → (dynamic) →* core::Type*
+    return super.{mai::Mixin2::field};
+  mixin-super-stub set field((dynamic) →* core::Type* value) → void
+    return super.{mai::Mixin2::field} = value;
+  mixin-super-stub method method1() → (dynamic) →* core::Type*
+    return super.{mai::Mixin2::method1}();
+  mixin-super-stub method method2((dynamic) →* core::Type* t) → void
+    return super.{mai::Mixin2::method2}(t);
+}
+class Class<T extends core::Object* = dynamic> extends self::_Class&Object&Mixin1&Mixin2<self::Class::T*> {
+  synthetic constructor •() → self::Class<self::Class::T*>*
+    : super self::_Class&Object&Mixin1&Mixin2::•()
+    ;
+  set field((dynamic) →* core::Type* value) → void {
+    super.{self::_Class&Object&Mixin1&Mixin2::field};
+    super.{self::_Class&Object&Mixin1&Mixin2::field} = value;
+    super.{self::_Class&Object&Mixin1&Mixin2::method1}();
+    super.{self::_Class&Object&Mixin1&Mixin2::method2}(null);
+  }
+}
+static method main() → dynamic {}
+
+library;
+import self as mai;
+import "dart:core" as core;
+import "main_lib2.dart" as mai2;
+
+import "org-dartlang-testcase:///main_lib2.dart";
+
+abstract class Mixin1<T extends core::Object* = dynamic> extends core::Object implements mai2::Interface<mai2::Value<dynamic>*, core::Object*> {
+  synthetic constructor •() → mai::Mixin1<mai::Mixin1::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get field() → (core::Object*) →* core::Type*; -> mai2::Interface::field
+  abstract member-signature set field((core::Object*) →* core::Type* value) → void; -> mai2::Interface::field
+  abstract member-signature method method1() → (core::Object*) →* core::Type*; -> mai2::Interface::method1
+  abstract member-signature method method2((core::Object*) →* core::Type* t) → void; -> mai2::Interface::method2
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Mixin2<T extends core::Object* = dynamic> extends core::Object implements mai2::Interface<mai2::Value<dynamic>*, core::Object*> {
+  field (dynamic) →* core::Type* field = null;
+  synthetic constructor •() → mai::Mixin2<mai::Mixin2::T*>*
+    : super core::Object::•()
+    ;
+  method method1() → (dynamic) →* core::Type*
+    return null;
+  method method2((dynamic) →* core::Type* t) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/super_access/main.no_link.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/super_access/main.no_link.dart.weak.modular.expect
new file mode 100644
index 0000000..6bf247e
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/super_access/main.no_link.dart.weak.modular.expect
@@ -0,0 +1,115 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "main_lib1.dart" as mai;
+import "main_lib2.dart" as mai2;
+
+import "org-dartlang-testcase:///main_lib1.dart";
+import "org-dartlang-testcase:///main_lib2.dart";
+
+abstract class _Class&Object&Mixin1<T extends core::Object* = dynamic> = core::Object with mai::Mixin1<self::_Class&Object&Mixin1::T*> /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_Class&Object&Mixin1<self::_Class&Object&Mixin1::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Class&Object&Mixin1&Mixin2<T extends core::Object* = dynamic> = self::_Class&Object&Mixin1<self::_Class&Object&Mixin1&Mixin2::T*> with mai::Mixin2<self::_Class&Object&Mixin1&Mixin2::T*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Object&Mixin1&Mixin2<self::_Class&Object&Mixin1&Mixin2::T*>*
+    : super self::_Class&Object&Mixin1::•()
+    ;
+  mixin-super-stub get field() → (dynamic) →* core::Type*
+    return super.{mai::Mixin2::field};
+  mixin-super-stub set field((dynamic) →* core::Type* value) → void
+    return super.{mai::Mixin2::field} = value;
+  mixin-super-stub method method1() → (dynamic) →* core::Type*
+    return super.{mai::Mixin2::method1}();
+  mixin-super-stub method method2((dynamic) →* core::Type* t) → void
+    return super.{mai::Mixin2::method2}(t);
+}
+class Class<T extends core::Object* = dynamic> extends self::_Class&Object&Mixin1&Mixin2<self::Class::T*> {
+  synthetic constructor •() → self::Class<self::Class::T*>*
+    : super self::_Class&Object&Mixin1&Mixin2::•()
+    ;
+  set field((dynamic) →* core::Type* value) → void {
+    super.{self::_Class&Object&Mixin1&Mixin2::field};
+    super.{self::_Class&Object&Mixin1&Mixin2::field} = value;
+    super.{self::_Class&Object&Mixin1&Mixin2::method1}();
+    super.{self::_Class&Object&Mixin1&Mixin2::method2}(null);
+  }
+}
+static method main() → dynamic {}
+
+library;
+import self as mai;
+import "dart:core" as core;
+import "main_lib2.dart" as mai2;
+
+import "org-dartlang-testcase:///main_lib2.dart";
+
+abstract class Mixin1<T extends core::Object* = dynamic> extends core::Object implements mai2::Interface<mai2::Value<dynamic>*, core::Object*> {
+  synthetic constructor •() → mai::Mixin1<mai::Mixin1::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get field() → (core::Object*) →* core::Type*; -> mai2::Interface::field
+  abstract member-signature set field((core::Object*) →* core::Type* value) → void; -> mai2::Interface::field
+  abstract member-signature method method1() → (core::Object*) →* core::Type*; -> mai2::Interface::method1
+  abstract member-signature method method2((core::Object*) →* core::Type* t) → void; -> mai2::Interface::method2
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class Mixin2<T extends core::Object* = dynamic> extends core::Object implements mai2::Interface<mai2::Value<dynamic>*, core::Object*> {
+  field (dynamic) →* core::Type* field = null;
+  synthetic constructor •() → mai::Mixin2<mai::Mixin2::T*>*
+    : super core::Object::•()
+    ;
+  method method1() → (dynamic) →* core::Type*
+    return null;
+  method method2((dynamic) →* core::Type* t) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+library /*isNonNullableByDefault*/;
+import self as mai2;
+import "dart:core" as core;
+
+typedef Typedef<unrelated T extends mai2::Value<dynamic>, contravariant I extends core::Object? = dynamic> = (I%) → core::Type;
+abstract class Value<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → mai2::Value<mai2::Value::T%>
+    : super core::Object::•()
+    ;
+}
+class Interface<T extends mai2::Value<dynamic>, I extends core::Object? = dynamic> extends core::Object {
+  field (mai2::Interface::I%) →? core::Type field = null;
+  synthetic constructor •() → mai2::Interface<mai2::Interface::T, mai2::Interface::I%>
+    : super core::Object::•()
+    ;
+  method method1() → (mai2::Interface::I%) →? core::Type
+    return null;
+  method method2((mai2::Interface::I%) →? core::Type t) → void {}
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/super_set_from_opt_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/super_set_from_opt_in.dart.weak.modular.expect
new file mode 100644
index 0000000..c317528
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/super_set_from_opt_in.dart.weak.modular.expect
@@ -0,0 +1,52 @@
+library;
+import self as self;
+import "super_set_from_opt_in_lib.dart" as sup;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///super_set_from_opt_in_lib.dart";
+
+abstract class Class extends sup::SuperClass<dynamic> {
+  synthetic constructor •() → self::Class*
+    : super sup::SuperClass::•()
+    ;
+  abstract member-signature get property() → core::Object*; -> sup::SuperClass::property
+  abstract member-signature set property(core::Object* value) → void; -> sup::SuperClass::property
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class SubClass extends self::Class {
+  synthetic constructor •() → self::SubClass*
+    : super self::Class::•()
+    ;
+  @#C1
+  set property(core::Object* value) → void {
+    super.{sup::SuperClass::property} = value;
+  }
+}
+static method main() → dynamic {
+  new self::SubClass::•().{self::SubClass::property} = null;
+}
+
+library /*isNonNullableByDefault*/;
+import self as sup;
+import "dart:core" as core;
+
+abstract class SuperClass<T extends core::Object? = dynamic> extends core::Object {
+  @#C1
+  field core::Object? property = null;
+  synthetic constructor •() → sup::SuperClass<sup::SuperClass::T%>
+    : super core::Object::•()
+    ;
+}
+
+constants  {
+  #C1 = core::_Override {}
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/type_parameter_nullability.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/type_parameter_nullability.dart.weak.modular.expect
new file mode 100644
index 0000000..726b3b6
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/type_parameter_nullability.dart.weak.modular.expect
@@ -0,0 +1,58 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "type_parameter_nullability_lib.dart" as typ;
+
+import "org-dartlang-testcase:///type_parameter_nullability_lib.dart";
+
+class C<T extends core::num?, S extends core::Object? = dynamic, U extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T%, self::C::S%, self::C::U%>
+    : super core::Object::•()
+    ;
+  method promoteNullable(covariant-by-class self::C::T? t) → void {
+    if(t is{ForNonNullableByDefault} core::int) {
+      t{self::C::T? & core::int /* '?' & '!' = '!' */};
+    }
+    if(t is{ForNonNullableByDefault} core::int?) {
+      t{self::C::T? & core::int? /* '?' & '?' = '?' */};
+    }
+  }
+  method nullableAsUndetermined(covariant-by-class self::C::S? s) → void {
+    s as{ForNonNullableByDefault} self::C::U%;
+  }
+}
+static method main() → dynamic {
+  self::C<core::num, core::num, core::num> c = new self::C::•<core::num, core::num, core::num>();
+  c.{self::C::promoteNullable}(null){(core::num?) → void};
+  c.{self::C::promoteNullable}(0){(core::num?) → void};
+  c.{self::C::nullableAsUndetermined}(null){(core::num?) → void};
+  c.{self::C::nullableAsUndetermined}(0){(core::num?) → void};
+  typ::D<core::num> d = new typ::D::•<core::num>();
+  d.{typ::D::promoteLegacy}(null){(core::num*) →* void};
+  d.{typ::D::promoteLegacy}(0){(core::num*) →* void};
+}
+
+library;
+import self as typ;
+import "dart:core" as core;
+
+class D<T extends core::num*> extends core::Object {
+  synthetic constructor •() → typ::D<typ::D::T*>*
+    : super core::Object::•()
+    ;
+  method promoteLegacy(covariant-by-class typ::D::T* t) → void {
+    if(t is core::int*) {
+      let final typ::D::T* & core::int* /* '*' & '*' = '*' */ #t1 = t{typ::D::T* & core::int* /* '*' & '*' = '*' */} in #t1 == null ?{core::bool*} null : #t1.{core::int::isEven}{core::bool*};
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/typedef_from_opt_in.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/typedef_from_opt_in.dart.weak.modular.expect
new file mode 100644
index 0000000..bebc221
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/typedef_from_opt_in.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library;
+import self as self;
+import "typedef_from_opt_in_lib.dart" as typ;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///typedef_from_opt_in_lib.dart";
+
+static method method1() → (typ::Request*) →* FutureOr<typ::Response*>*
+  return (typ::Request* r) → asy::Future<typ::Response*>* async => new typ::Response::•();
+static method method2() → (core::int*) →* core::int*
+  return (core::int* r) → core::int* => 0;
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as typ;
+import "dart:core" as core;
+
+import "dart:async";
+
+typedef Handler = (typ::Request) → FutureOr<typ::Response>;
+typedef Typedef = (core::int?) → core::int;
+class Request extends core::Object {
+  synthetic constructor •() → typ::Request
+    : super core::Object::•()
+    ;
+}
+class Response extends core::Object {
+  synthetic constructor •() → typ::Response
+    : super core::Object::•()
+    ;
+}
diff --git a/pkg/front_end/testcases/nnbd_mixed/unsound_checks.dart.weak.modular.expect b/pkg/front_end/testcases/nnbd_mixed/unsound_checks.dart.weak.modular.expect
new file mode 100644
index 0000000..5076108
--- /dev/null
+++ b/pkg/front_end/testcases/nnbd_mixed/unsound_checks.dart.weak.modular.expect
@@ -0,0 +1,626 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "unsound_checks_lib.dart" as uns;
+
+import "org-dartlang-testcase:///unsound_checks_lib.dart";
+
+class OptOutClass1 extends core::Object {
+  synthetic constructor •() → self::OptOutClass1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class OptOutClass2 extends core::Object {
+  synthetic constructor •() → self::OptOutClass2*
+    : super core::Object::•()
+    ;
+  operator [](core::int* index) → core::int*
+    return index;
+  operator []=(core::int* index, core::int* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class OptOutClass3 extends core::Object {
+  field core::int* field;
+  constructor •(core::int* field) → self::OptOutClass3*
+    : self::OptOutClass3::field = field, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class OptOutSuperClass4 extends core::Object {
+  synthetic constructor •() → self::OptOutSuperClass4*
+    : super core::Object::•()
+    ;
+  operator [](core::int* index) → core::int*
+    return index;
+  operator []=(core::int* index, core::int* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class OptOutClass4 extends self::OptOutSuperClass4 {
+  synthetic constructor •() → self::OptOutClass4*
+    : super self::OptOutSuperClass4::•()
+    ;
+  method method(core::int* i) → dynamic
+    return let final core::int* #t1 = i in let final core::int* #t2 = super.{self::OptOutSuperClass4::[]}(#t1) in #t2 == null ?{core::int*} let final core::int* #t3 = 42 in let final void #t4 = super.{self::OptOutSuperClass4::[]=}(#t1, #t3) in #t3 : #t2;
+  method methodForEffect(core::int* i) → dynamic {
+    let final core::int* #t5 = i in super.{self::OptOutSuperClass4::[]}(#t5) == null ?{core::int*} super.{self::OptOutSuperClass4::[]=}(#t5, 42) : null;
+  }
+}
+class OptOutClass5 extends core::Object {
+  field core::int* field;
+  constructor •(core::int* field) → self::OptOutClass5*
+    : self::OptOutClass5::field = field, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+extension OptOutExtension on self::OptOutClass1* {
+  operator [] = self::OptOutExtension|[];
+  operator []= = self::OptOutExtension|[]=;
+}
+static method isNullOptOut1(core::int* i) → dynamic
+  return i == null;
+static method isNotNullOptOut1(core::int* i) → dynamic
+  return !(i == null);
+static method isNullOptOut2(core::int* i) → dynamic
+  return i == null;
+static method isNotNullOptOut2(core::int* i) → dynamic
+  return !(i == null);
+static method ifNullOptOut(core::int* i) → dynamic
+  return let final core::int* #t6 = i in #t6 == null ?{core::int*} 42 : #t6;
+static method OptOutExtension|[](lowered final self::OptOutClass1* #this, core::int* index) → core::int*
+  return index;
+static method OptOutExtension|[]=(lowered final self::OptOutClass1* #this, core::int* index, core::int* value) → void {}
+static method extensionIfNullOptOut1(core::int* i) → dynamic
+  return let final self::OptOutClass1* #t7 = new self::OptOutClass1::•() in let final core::int* #t8 = i in let final core::int* #t9 = self::OptOutExtension|[](#t7, #t8) in #t9 == null ?{core::int*} let final core::int* #t10 = 42 in let final void #t11 = self::OptOutExtension|[]=(#t7, #t8, #t10) in #t10 : #t9;
+static method extensionIfNullOptOut1ForEffect(core::int* i) → dynamic {
+  let final self::OptOutClass1* #t12 = new self::OptOutClass1::•() in let final core::int* #t13 = i in self::OptOutExtension|[](#t12, #t13) == null ?{core::int*} self::OptOutExtension|[]=(#t12, #t13, 42) : null;
+}
+static method extensionIfNullOptOut2(core::int* i) → dynamic
+  return let final self::OptOutClass1* #t14 = new self::OptOutClass1::•() in let final core::int* #t15 = i in let final core::int* #t16 = self::OptOutExtension|[](#t14, #t15) in #t16 == null ?{core::int*} let final core::int* #t17 = 42 in let final void #t18 = self::OptOutExtension|[]=(#t14, #t15, #t17) in #t17 : #t16;
+static method extensionIfNullOptOut2ForEffect(core::int* i) → dynamic {
+  let final self::OptOutClass1* #t19 = new self::OptOutClass1::•() in let final core::int* #t20 = i in self::OptOutExtension|[](#t19, #t20) == null ?{core::int*} self::OptOutExtension|[]=(#t19, #t20, 42) : null;
+}
+static method ifNullIndexSetOptOut(core::int* i) → dynamic
+  return let final self::OptOutClass2* #t21 = new self::OptOutClass2::•() in let final core::int* #t22 = i in let final core::int* #t23 = #t21.{self::OptOutClass2::[]}(#t22){(core::int*) →* core::int*} in #t23 == null ?{core::int*} let final core::int* #t24 = 42 in let final void #t25 = #t21.{self::OptOutClass2::[]=}(#t22, #t24){(core::int*, core::int*) →* void} in #t24 : #t23;
+static method ifNullIndexSetOptOutForEffect(core::int* i) → dynamic {
+  let final self::OptOutClass2* #t26 = new self::OptOutClass2::•() in let final core::int* #t27 = i in #t26.{self::OptOutClass2::[]}(#t27){(core::int*) →* core::int*} == null ?{core::int*} #t26.{self::OptOutClass2::[]=}(#t27, 42){(core::int*, core::int*) →* void} : null;
+}
+static method ifNullPropertySetOptOut(core::int* i) → dynamic
+  return let final self::OptOutClass3* #t28 = new self::OptOutClass3::•(i) in let final core::int* #t29 = #t28.{self::OptOutClass3::field}{core::int*} in #t29 == null ?{core::int*} #t28.{self::OptOutClass3::field} = 42 : #t29;
+static method ifNullPropertySetOptOutForEffect(core::int* i) → dynamic {
+  let final self::OptOutClass3* #t30 = new self::OptOutClass3::•(i) in #t30.{self::OptOutClass3::field}{core::int*} == null ?{core::int*} #t30.{self::OptOutClass3::field} = 42 : null;
+}
+static method ifNullSetOptOut(core::int* i) → dynamic
+  return let final core::int* #t31 = i in #t31 == null ?{core::int*} i = 42 : #t31;
+static method ifNullSetOptOutForEffect(core::int* i) → dynamic {
+  i == null ?{core::int*} i = 42 : null;
+}
+static method ifNullSuperIndexSetOptOut(core::int* i) → dynamic
+  return new self::OptOutClass4::•().{self::OptOutClass4::method}(i){(core::int*) →* dynamic};
+static method ifNullSuperIndexSetOptOutForEffect(core::int* i) → dynamic {
+  new self::OptOutClass4::•().{self::OptOutClass4::methodForEffect}(i){(core::int*) →* dynamic};
+}
+static method nullAwareIfNullSetOptOut(core::int* i) → dynamic {
+  self::OptOutClass5* o = new self::OptOutClass5::•(i);
+  return let final self::OptOutClass5* #t32 = o in #t32 == null ?{core::int*} null : let final core::int* #t33 = #t32.{self::OptOutClass5::field}{core::int*} in #t33 == null ?{core::int*} #t32.{self::OptOutClass5::field} = 42 : #t33;
+}
+static method nullAwareIfNullSetOptOutForEffect(core::int* i) → dynamic {
+  self::OptOutClass5* o = new self::OptOutClass5::•(i);
+  let final self::OptOutClass5* #t34 = o in #t34 == null ?{core::int*} null : #t34.{self::OptOutClass5::field}{core::int*} == null ?{core::int*} #t34.{self::OptOutClass5::field} = 42 : null;
+}
+static method isTestOptOut(core::int* i) → dynamic
+  return i is core::int*;
+static method isNotTestOptOut(core::int* i) → dynamic
+  return !(i is core::int*);
+static method main() → dynamic {
+  self::expect(false, uns::isNullOptIn1(0));
+  self::expect(false, self::isNullOptOut1(0));
+  self::expect(true, uns::isNullOptIn1(null));
+  self::expect(true, self::isNullOptOut1(null));
+  self::expect(true, uns::isNotNullOptIn1(0));
+  self::expect(true, self::isNotNullOptOut1(0));
+  self::expect(false, uns::isNotNullOptIn1(null));
+  self::expect(false, self::isNotNullOptOut1(null));
+  self::expect(false, uns::isNullOptIn2(0));
+  self::expect(false, self::isNullOptOut2(0));
+  self::expect(true, uns::isNullOptIn2(null));
+  self::expect(true, self::isNullOptOut2(null));
+  self::expect(true, uns::isNotNullOptIn2(0));
+  self::expect(true, self::isNotNullOptOut2(0));
+  self::expect(false, uns::isNotNullOptIn2(null));
+  self::expect(false, self::isNotNullOptOut2(null));
+  self::expect(0, uns::ifNullOptIn(0));
+  self::expect(0, self::ifNullOptOut(0));
+  self::expect(42, uns::ifNullOptIn(null));
+  self::expect(42, self::ifNullOptOut(null));
+  self::expect(0, uns::extensionIfNullOptIn1(0));
+  self::expect(0, self::extensionIfNullOptOut1(0));
+  self::expect(42, uns::extensionIfNullOptIn1(null));
+  self::expect(42, self::extensionIfNullOptOut1(null));
+  uns::extensionIfNullOptIn1ForEffect(0);
+  self::extensionIfNullOptOut1ForEffect(0);
+  uns::extensionIfNullOptIn1ForEffect(null);
+  self::extensionIfNullOptOut1ForEffect(null);
+  self::expect(0, uns::extensionIfNullOptIn2(0));
+  self::expect(0, self::extensionIfNullOptOut2(0));
+  self::expect(42, uns::extensionIfNullOptIn2(null));
+  self::expect(42, self::extensionIfNullOptOut2(null));
+  uns::extensionIfNullOptIn2ForEffect(0);
+  self::extensionIfNullOptOut2ForEffect(0);
+  uns::extensionIfNullOptIn2ForEffect(null);
+  self::extensionIfNullOptOut2ForEffect(null);
+  self::expect(0, uns::ifNullIndexSetOptIn(0));
+  self::expect(0, self::ifNullIndexSetOptOut(0));
+  self::expect(42, uns::ifNullIndexSetOptIn(null));
+  self::expect(42, self::ifNullIndexSetOptOut(null));
+  uns::ifNullIndexSetOptInForEffect(0);
+  self::ifNullIndexSetOptOutForEffect(0);
+  uns::ifNullIndexSetOptInForEffect(null);
+  self::ifNullIndexSetOptOutForEffect(null);
+  self::expect(0, uns::ifNullPropertySetOptIn(0));
+  self::expect(0, self::ifNullPropertySetOptOut(0));
+  self::expect(42, uns::ifNullPropertySetOptIn(null));
+  self::expect(42, self::ifNullPropertySetOptOut(null));
+  uns::ifNullPropertySetOptInForEffect(0);
+  self::ifNullPropertySetOptOutForEffect(0);
+  uns::ifNullPropertySetOptInForEffect(null);
+  self::ifNullPropertySetOptOutForEffect(null);
+  self::expect(0, uns::ifNullSetOptIn(0));
+  self::expect(0, self::ifNullSetOptOut(0));
+  self::expect(42, uns::ifNullSetOptIn(null));
+  self::expect(42, self::ifNullSetOptOut(null));
+  uns::ifNullSetOptInForEffect(0);
+  self::ifNullSetOptOutForEffect(0);
+  uns::ifNullSetOptInForEffect(null);
+  self::ifNullSetOptOutForEffect(null);
+  self::expect(0, uns::ifNullSuperIndexSetOptIn(0));
+  self::expect(0, self::ifNullSuperIndexSetOptOut(0));
+  self::expect(42, uns::ifNullSuperIndexSetOptIn(null));
+  self::expect(42, self::ifNullSuperIndexSetOptOut(null));
+  uns::ifNullSuperIndexSetOptInForEffect(0);
+  self::ifNullSuperIndexSetOptOutForEffect(0);
+  uns::ifNullSuperIndexSetOptInForEffect(null);
+  self::ifNullSuperIndexSetOptOutForEffect(null);
+  self::expect(0, uns::nullAwareIfNullSetOptIn(0));
+  self::expect(0, self::nullAwareIfNullSetOptOut(0));
+  self::expect(42, uns::nullAwareIfNullSetOptIn(null));
+  self::expect(42, self::nullAwareIfNullSetOptOut(null));
+  uns::nullAwareIfNullSetOptInForEffect(0);
+  self::nullAwareIfNullSetOptOutForEffect(0);
+  uns::nullAwareIfNullSetOptInForEffect(null);
+  self::nullAwareIfNullSetOptOutForEffect(null);
+  self::expect(true, uns::isTestOptIn(0));
+  self::expect(true, self::isTestOptOut(0));
+  self::expect(false, uns::isTestOptIn(null));
+  self::expect(false, self::isTestOptOut(null));
+  self::expect(false, uns::isNotTestOptIn(0));
+  self::expect(false, self::isNotTestOptOut(0));
+  self::expect(true, uns::isNotTestOptIn(null));
+  self::expect(true, self::isNotTestOptOut(null));
+  self::expect(true, uns::nullAwareAccess1(0));
+  self::expect(null, uns::nullAwareAccess1(null));
+  uns::promotionToNever(0);
+  uns::promotionToNever(null);
+  uns::unnecessaryNullCheck(() → core::int* => 0);
+  uns::unnecessaryNullCheck(() → Null => null);
+  self::expect(0, uns::unnecessaryIfNull(() → core::int* => 0, () → core::int* => 42));
+  self::expect(42, uns::unnecessaryIfNull(() → Null => null, () → core::int* => 42));
+  uns::unnecessaryIfNullAssign(<core::int*>[0], () → core::int* => 42);
+  uns::unnecessaryIfNullAssign(<core::int*>[null], () → core::int* => 42);
+  uns::unnecessaryNullAwareAccess(() → core::int* => 0);
+  uns::unnecessaryNullAwareAccess(() → Null => null);
+  self::throws(() → dynamic => uns::callReturningNever(() → Null => throw "foo"), (core::Object* e) → core::bool* => e =={core::Object::==}{(core::Object*) →* core::bool*} "foo");
+  () →* Null f = () → Null => null;
+  self::throws(() → dynamic => uns::callReturningNever(f));
+  uns::switchOnEnum(#C3);
+  uns::switchOnEnum(#C6);
+  self::throws(() → dynamic => uns::switchOnEnum(null));
+  uns::switchOnEnumWithBreak(#C3);
+  uns::switchOnEnumWithBreak(#C6);
+  self::throws(() → dynamic => uns::switchOnEnumWithBreak(null));
+  uns::switchOnEnumWithFallThrough1(#C3);
+  uns::switchOnEnumWithFallThrough1(#C6);
+  self::throws(() → dynamic => uns::switchOnEnumWithFallThrough1(null));
+  uns::switchOnEnumWithFallThrough2(#C3);
+  uns::switchOnEnumWithFallThrough2(#C6);
+  self::throws(() → dynamic => uns::switchOnEnumWithFallThrough2(null));
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() →* void f, [(core::Object*) →* core::bool* testException = #C7]) → dynamic {
+  try {
+    f(){() →* void};
+  }
+  on dynamic catch(final dynamic e) {
+    if(!(testException == null) && !testException(e){(core::Object*) →* core::bool*}) {
+      throw "Unexpected exception: ${e}";
+    }
+    core::print(e);
+    return;
+  }
+  throw "Missing exception.";
+}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:13:23: Warning: Operand of null-aware operation '??' has type 'int' which excludes null.
+// ifNullOptIn(int i) => i ?? 42;
+//                       ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:22:66: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+// extensionIfNullOptIn1(int i) => OptInExtension(new OptInClass1())[i] ??= 42;
+//                                                                  ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:25:36: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   OptInExtension(new OptInClass1())[i] ??= 42;
+//                                    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:28:50: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+// extensionIfNullOptIn2(int i) => new OptInClass1()[i] ??= 42;
+//                                                  ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:31:20: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   new OptInClass1()[i] ??= 42;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:39:48: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+// ifNullIndexSetOptIn(int i) => new OptInClass2()[i] ??= 42;
+//                                                ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:42:20: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   new OptInClass2()[i] ??= 42;
+//                    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:51:53: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+// ifNullPropertySetOptIn(int i) => new OptInClass3(i).field ??= 42;
+//                                                     ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:54:22: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   new OptInClass3(i).field ??= 42;
+//                      ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:57:26: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+// ifNullSetOptIn(int i) => i ??= 42;
+//                          ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:60:3: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   i ??= 42;
+//   ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:69:25: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   method(int i) => super[i] ??= 42;
+//                         ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:71:10: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//     super[i] ??= 42;
+//          ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:113:28: Warning: Operand of null-aware operation '?.' has type 'int' which excludes null.
+// nullAwareAccess1(int i) => i?.isEven;
+//                            ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:116:3: Warning: Operand of null-aware operation '?.' has type 'int' which excludes null.
+//   i?.isEven;
+//   ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:128:11: Warning: Operand of null-aware operation '??' has type 'int' which excludes null.
+//   return f() ??
+//           ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:134:4: Warning: Operand of null-aware operation '??=' has type 'int' which excludes null.
+//   x[0] ??= f();
+//    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:138:4: Warning: Operand of null-aware operation '?.' has type 'int' which excludes null.
+//   f()?.gcd(0); // Should not throw if `f` returns null
+//    ^
+//
+// pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:195:10: Error: Not enough type information to disambiguate between literal set and literal map.
+// Try providing type arguments for the literal explicitly to disambiguate it.
+//   return {...d}; // Should not throw ReachabilityError.
+//          ^
+//
+import self as uns;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class OptInClass1 extends core::Object {
+  synthetic constructor •() → uns::OptInClass1
+    : super core::Object::•()
+    ;
+}
+class OptInClass2 extends core::Object {
+  synthetic constructor •() → uns::OptInClass2
+    : super core::Object::•()
+    ;
+  operator [](core::int index) → core::int
+    return index;
+  operator []=(core::int index, core::int value) → void {}
+}
+class OptInClass3 extends core::Object {
+  field core::int field;
+  constructor •(core::int field) → uns::OptInClass3
+    : uns::OptInClass3::field = field, super core::Object::•()
+    ;
+}
+class OptInSuperClass4 extends core::Object {
+  synthetic constructor •() → uns::OptInSuperClass4
+    : super core::Object::•()
+    ;
+  operator [](core::int index) → core::int
+    return index;
+  operator []=(core::int index, core::int value) → void {}
+}
+class OptInClass4 extends uns::OptInSuperClass4 {
+  synthetic constructor •() → uns::OptInClass4
+    : super uns::OptInSuperClass4::•()
+    ;
+  method method(core::int i) → dynamic
+    return let final core::int #t35 = i in let final core::int #t36 = super.{uns::OptInSuperClass4::[]}(#t35) in #t36 == null ?{core::int} let final core::int #t37 = 42 in let final void #t38 = super.{uns::OptInSuperClass4::[]=}(#t35, #t37) in #t37 : #t36;
+  method methodForEffect(core::int i) → dynamic {
+    let final core::int #t39 = i in super.{uns::OptInSuperClass4::[]}(#t39) == null ?{core::int} super.{uns::OptInSuperClass4::[]=}(#t39, 42) : null;
+  }
+}
+class OptInClass5 extends core::Object {
+  field core::int field;
+  constructor •(core::int field) → uns::OptInClass5
+    : uns::OptInClass5::field = field, super core::Object::•()
+    ;
+}
+class OptInClass6a extends core::Object {
+  final field uns::OptInClass6b cls;
+  constructor •(uns::OptInClass6b cls) → uns::OptInClass6a
+    : uns::OptInClass6a::cls = cls, super core::Object::•()
+    ;
+}
+class OptInClass6b extends core::Object {
+  final field core::int field;
+  constructor •(core::int field) → uns::OptInClass6b
+    : uns::OptInClass6b::field = field, super core::Object::•()
+    ;
+}
+class E extends core::_Enum /*isEnum*/  {
+  static const field core::List<uns::E> values = #C8;
+  static const field uns::E e1 = #C3;
+  static const field uns::E e2 = #C6;
+  const constructor •(core::int index, core::String name) → uns::E
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String
+    return "E.${this.{core::_Enum::_name}{core::String}}";
+}
+extension OptInExtension on uns::OptInClass1 {
+  operator [] = uns::OptInExtension|[];
+  operator []= = uns::OptInExtension|[]=;
+}
+static method isNullOptIn1(core::int i) → dynamic
+  return i == null;
+static method isNotNullOptIn1(core::int i) → dynamic
+  return !(i == null);
+static method isNullOptIn2(core::int i) → dynamic
+  return i == null;
+static method isNotNullOptIn2(core::int i) → dynamic
+  return !(i == null);
+static method ifNullOptIn(core::int i) → dynamic
+  return let final core::int #t40 = i in #t40 == null ?{core::int} 42 : #t40;
+static method OptInExtension|[](lowered final uns::OptInClass1 #this, core::int index) → core::int
+  return index;
+static method OptInExtension|[]=(lowered final uns::OptInClass1 #this, core::int index, core::int value) → void {}
+static method extensionIfNullOptIn1(core::int i) → dynamic
+  return let final uns::OptInClass1 #t41 = new uns::OptInClass1::•() in let final core::int #t42 = i in let final core::int #t43 = uns::OptInExtension|[](#t41, #t42) in #t43 == null ?{core::int} let final core::int #t44 = 42 in let final void #t45 = uns::OptInExtension|[]=(#t41, #t42, #t44) in #t44 : #t43;
+static method extensionIfNullOptIn1ForEffect(core::int i) → dynamic {
+  let final uns::OptInClass1 #t46 = new uns::OptInClass1::•() in let final core::int #t47 = i in uns::OptInExtension|[](#t46, #t47) == null ?{core::int} uns::OptInExtension|[]=(#t46, #t47, 42) : null;
+}
+static method extensionIfNullOptIn2(core::int i) → dynamic
+  return let final uns::OptInClass1 #t48 = new uns::OptInClass1::•() in let final core::int #t49 = i in let final core::int #t50 = uns::OptInExtension|[](#t48, #t49) in #t50 == null ?{core::int} let final core::int #t51 = 42 in let final void #t52 = uns::OptInExtension|[]=(#t48, #t49, #t51) in #t51 : #t50;
+static method extensionIfNullOptIn2ForEffect(core::int i) → dynamic {
+  let final uns::OptInClass1 #t53 = new uns::OptInClass1::•() in let final core::int #t54 = i in uns::OptInExtension|[](#t53, #t54) == null ?{core::int} uns::OptInExtension|[]=(#t53, #t54, 42) : null;
+}
+static method ifNullIndexSetOptIn(core::int i) → dynamic
+  return let final uns::OptInClass2 #t55 = new uns::OptInClass2::•() in let final core::int #t56 = i in let final core::int #t57 = #t55.{uns::OptInClass2::[]}(#t56){(core::int) → core::int} in #t57 == null ?{core::int} let final core::int #t58 = 42 in let final void #t59 = #t55.{uns::OptInClass2::[]=}(#t56, #t58){(core::int, core::int) → void} in #t58 : #t57;
+static method ifNullIndexSetOptInForEffect(core::int i) → dynamic {
+  let final uns::OptInClass2 #t60 = new uns::OptInClass2::•() in let final core::int #t61 = i in #t60.{uns::OptInClass2::[]}(#t61){(core::int) → core::int} == null ?{core::int} #t60.{uns::OptInClass2::[]=}(#t61, 42){(core::int, core::int) → void} : null;
+}
+static method ifNullPropertySetOptIn(core::int i) → dynamic
+  return let final uns::OptInClass3 #t62 = new uns::OptInClass3::•(i) in let final core::int #t63 = #t62.{uns::OptInClass3::field}{core::int} in #t63 == null ?{core::int} #t62.{uns::OptInClass3::field} = 42 : #t63;
+static method ifNullPropertySetOptInForEffect(core::int i) → dynamic {
+  let final uns::OptInClass3 #t64 = new uns::OptInClass3::•(i) in #t64.{uns::OptInClass3::field}{core::int} == null ?{core::int} #t64.{uns::OptInClass3::field} = 42 : null;
+}
+static method ifNullSetOptIn(core::int i) → dynamic
+  return let final core::int #t65 = i in #t65 == null ?{core::int} i = 42 : #t65;
+static method ifNullSetOptInForEffect(core::int i) → dynamic {
+  i == null ?{core::int} i = 42 : null;
+}
+static method ifNullSuperIndexSetOptIn(core::int i) → dynamic
+  return new uns::OptInClass4::•().{uns::OptInClass4::method}(i){(core::int) → dynamic};
+static method ifNullSuperIndexSetOptInForEffect(core::int i) → dynamic {
+  new uns::OptInClass4::•().{uns::OptInClass4::methodForEffect}(i){(core::int) → dynamic};
+}
+static method nullAwareIfNullSetOptIn(core::int i) → dynamic {
+  uns::OptInClass5? o = new uns::OptInClass5::•(i) as{ForNonNullableByDefault} uns::OptInClass5?;
+  return let final uns::OptInClass5? #t66 = o in #t66 == null ?{core::int?} null : let final core::int #t67 = #t66.{uns::OptInClass5::field}{core::int} in #t67 == null ?{core::int} #t66.{uns::OptInClass5::field} = 42 : #t67;
+}
+static method nullAwareIfNullSetOptInForEffect(core::int i) → dynamic {
+  uns::OptInClass5? o = new uns::OptInClass5::•(i) as{ForNonNullableByDefault} uns::OptInClass5?;
+  let final uns::OptInClass5? #t68 = o in #t68 == null ?{core::int?} null : #t68.{uns::OptInClass5::field}{core::int} == null ?{core::int} #t68.{uns::OptInClass5::field} = 42 : null;
+}
+static method isTestOptIn(core::int i) → dynamic
+  return i is{ForNonNullableByDefault} core::int;
+static method isNotTestOptIn(core::int i) → dynamic
+  return !(i is{ForNonNullableByDefault} core::int);
+static method nullAwareAccess1(core::int i) → dynamic
+  return let final core::int #t69 = i in #t69 == null ?{core::bool?} null : #t69.{core::int::isEven}{core::bool};
+static method nullAwareAccessForEffect1(core::int i) → dynamic {
+  let final core::int #t70 = i in #t70 == null ?{core::bool?} null : #t70.{core::int::isEven}{core::bool};
+}
+static method promotionToNever(core::int i) → dynamic {
+  if(i is{ForNonNullableByDefault} core::int)
+    return;
+}
+static method unnecessaryNullCheck(() → core::int f) → dynamic {
+  if(!(f(){() → core::int} == null))
+    return;
+}
+static method unnecessaryIfNull(() → core::int f, () → core::int g) → dynamic {
+  return let final core::int #t71 = f(){() → core::int} in #t71 == null ?{core::int} g(){() → core::int} : #t71;
+}
+static method unnecessaryIfNullAssign(core::List<core::int> x, () → core::int f) → dynamic {
+  let final core::List<core::int> #t72 = x in let final core::int #t73 = 0 in #t72.{core::List::[]}(#t73){(core::int) → core::int} == null ?{core::int} #t72.{core::List::[]=}(#t73, f(){() → core::int}){(core::int, core::int) → void} : null;
+}
+static method unnecessaryNullAwareAccess(() → core::int f) → dynamic {
+  let final core::int #t74 = f(){() → core::int} in #t74 == null ?{core::int?} null : #t74.{core::int::gcd}(0){(core::int) → core::int};
+}
+static method callReturningNever(() → Never f) → dynamic {
+  let final Never #t75 = f(){() → Never} in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+}
+static method switchOnEnum(uns::E e) → dynamic {
+  switch(e) {
+    #L1:
+    case #C3:
+      {
+        return;
+      }
+    #L2:
+    case #C6:
+      {
+        return;
+      }
+    #L3:
+    default:
+      throw new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable enum type.");
+  }
+}
+static method switchOnEnumWithBreak(uns::E e) → dynamic {
+  #L4:
+  switch(e) {
+    #L5:
+    case #C3:
+      {
+        break #L4;
+      }
+    #L6:
+    case #C6:
+      {
+        break #L4;
+      }
+    #L7:
+    default:
+      throw new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable enum type.");
+  }
+}
+static method switchOnEnumWithFallThrough1(uns::E e) → dynamic {
+  #L8:
+  switch(e) {
+    #L9:
+    case #C3:
+      {
+        break #L8;
+      }
+    #L10:
+    case #C6:
+      {
+        break #L8;
+      }
+    #L11:
+    default:
+      throw new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable enum type.");
+  }
+}
+static method switchOnEnumWithFallThrough2(uns::E e) → dynamic {
+  #L12:
+  switch(e) {
+    #L13:
+    case #C3:
+    case #C6:
+      {
+        break #L12;
+      }
+    #L14:
+    default:
+      throw new _in::ReachabilityError::•("`null` encountered as case in a switch expression with a non-nullable enum type.");
+  }
+}
+static method handleThrow() → dynamic {
+  throw "";
+}
+static method handleRethrow() → dynamic {
+  try {
+    uns::handleThrow();
+  }
+  on core::Object catch(final core::Object _) {
+    rethrow;
+  }
+}
+static method handleInvalid(dynamic d) → dynamic {
+  return invalid-expression "pkg/front_end/testcases/nnbd_mixed/unsound_checks_lib.dart:195:10: Error: Not enough type information to disambiguate between literal set and literal map.
+Try providing type arguments for the literal explicitly to disambiguate it.
+  return {...d}; // Should not throw ReachabilityError.
+         ^";
+}
+
+constants  {
+  #C1 = 0
+  #C2 = "e1"
+  #C3 = uns::E {index:#C1, _name:#C2}
+  #C4 = 1
+  #C5 = "e2"
+  #C6 = uns::E {index:#C4, _name:#C5}
+  #C7 = null
+  #C8 = <uns::E*>[#C3, #C6]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///unsound_checks_lib.dart:
+- E. (from org-dartlang-testcase:///unsound_checks_lib.dart:145:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:76:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/abstract_accessors_from_field.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/abstract_accessors_from_field.dart.weak.modular.expect
new file mode 100644
index 0000000..8a70236
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/abstract_accessors_from_field.dart.weak.modular.expect
@@ -0,0 +1,66 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class I extends core::Object {
+  field core::int* foo = null;
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends core::Object implements self::I {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic
+    return "bar";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder get foo() → core::int*
+    return this.{self::A::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::int*;
+  no-such-method-forwarder set foo(core::int* value) → void
+    return this.{self::A::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+static method expectTypeError(() →* dynamic callback) → void {
+  try {
+    callback(){() →* dynamic};
+    throw "Expected TypeError, did not occur";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
+static method main() → dynamic {
+  self::A* a = new self::A::•();
+  self::expectTypeError(() → core::int* => a.{self::I::foo}{core::int*});
+  self::expectTypeError(() → core::String* => (a as dynamic){dynamic}.foo = "bar");
+}
+
+constants  {
+  #C1 = #foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+  #C5 = #foo=
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/abstract_accessors_from_field_arent_mixed_in.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/abstract_accessors_from_field_arent_mixed_in.dart.weak.modular.expect
new file mode 100644
index 0000000..c5739de
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/abstract_accessors_from_field_arent_mixed_in.dart.weak.modular.expect
@@ -0,0 +1,85 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  field core::int* foo = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::A {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic {
+    self::count = self::count.{core::num::+}(1){(core::num*) →* core::int*};
+    return null;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder get foo() → core::int*
+    return this.{self::B::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::int*;
+  no-such-method-forwarder set foo(core::int* value) → void
+    return this.{self::B::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+abstract class _C&Object&B = core::Object with self::B /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_C&Object&B*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method noSuchMethod(core::Invocation* i) → dynamic
+    return super.{self::B::noSuchMethod}(i);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::_C&Object&B {
+  synthetic constructor •() → self::C*
+    : super self::_C&Object&B::•()
+    ;
+  get foo() → core::int*
+    return 42;
+  set foo(core::int* value) → void {}
+}
+static field core::int* count = 0;
+static method main() → dynamic {
+  self::C* c = new self::C::•();
+  if(!(c.{self::C::foo}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} 42)) {
+    throw "Value mismatch: c.foo != 42.";
+  }
+  c.{self::C::foo} = 43;
+  if(!(self::count =={core::num::==}{(core::Object*) →* core::bool*} 0)) {
+    throw "Value mismatch: count != 0";
+  }
+}
+
+constants  {
+  #C1 = #foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+  #C5 = #foo=
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/abstract_accessors_from_field_one_defined.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/abstract_accessors_from_field_one_defined.dart.weak.modular.expect
new file mode 100644
index 0000000..49adc6d
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/abstract_accessors_from_field_one_defined.dart.weak.modular.expect
@@ -0,0 +1,91 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  field core::int* foo = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends core::Object implements self::A {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  get foo() → core::int*
+    return 42;
+  method noSuchMethod(core::Invocation* i) → dynamic
+    return "bar";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  no-such-method-forwarder set foo(core::int* value) → void
+    return this.{self::B::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C3))){(core::Invocation*) →* dynamic};
+}
+abstract class D extends core::Object implements self::A {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  set foo(core::int* value) → void {}
+  method noSuchMethod(core::Invocation* i) → dynamic
+    return "bar";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E extends self::D {
+  synthetic constructor •() → self::E*
+    : super self::D::•()
+    ;
+  no-such-method-forwarder get foo() → core::int*
+    return this.{self::D::noSuchMethod}(new core::_InvocationMirror::_withType(#C4, 1, #C2, #C5, core::Map::unmodifiable<core::Symbol*, dynamic>(#C3))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::int*;
+}
+static method expectTypeError(() →* dynamic callback) → void {
+  try {
+    callback(){() →* dynamic};
+    throw "Expected TypeError, did not occur";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
+static method main() → dynamic {
+  self::C* c = new self::C::•();
+  self::expectTypeError(() → core::String* => (c as dynamic){dynamic}.foo = "bar");
+  self::E* e = new self::E::•();
+  self::expectTypeError(() → core::int* => e.{self::A::foo}{core::int*});
+}
+
+constants  {
+  #C1 = #foo=
+  #C2 = <core::Type*>[]
+  #C3 = <core::Symbol*, dynamic>{)
+  #C4 = #foo
+  #C5 = <dynamic>[]
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/abstract_accessors_from_field_with_substitution.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/abstract_accessors_from_field_with_substitution.dart.weak.modular.expect
new file mode 100644
index 0000000..aa77c05
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/abstract_accessors_from_field_with_substitution.dart.weak.modular.expect
@@ -0,0 +1,61 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class A<X extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field core::List<self::A::X*>* foo = null;
+  synthetic constructor •() → self::A<self::A::X*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::A<core::int*> {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic
+    return <dynamic>[];
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder get foo() → core::List<core::int*>*
+    return this.{self::B::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::List<core::int*>*;
+  no-such-method-forwarder set foo(covariant-by-class core::List<core::int*>* value) → void
+    return this.{self::B::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+static method expectTypeError(() →* dynamic callback) → void {
+  try {
+    callback(){() →* dynamic};
+    throw "Expected TypeError, did not occur";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
+static method main() → dynamic {
+  self::B* b = new self::B::•();
+  self::expectTypeError(() → core::List<core::int*>* => b.{self::A::foo}{core::List<core::int*>*});
+  self::expectTypeError(() → core::List<dynamic>* => (b as dynamic){dynamic}.foo = <dynamic>[]);
+}
+
+constants  {
+  #C1 = #foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+  #C5 = #foo=
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/abstract_interface_nsm_inherited.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/abstract_interface_nsm_inherited.dart.weak.modular.expect
new file mode 100644
index 0000000..06dbd87
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/abstract_interface_nsm_inherited.dart.weak.modular.expect
@@ -0,0 +1,52 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic {
+    return null;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  abstract method foo() → void;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A implements self::I {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  no-such-method-forwarder method foo() → void
+    return this.{self::A::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/abstract_override_abstract_different_type.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/abstract_override_abstract_different_type.dart.weak.modular.expect
new file mode 100644
index 0000000..a135817
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/abstract_override_abstract_different_type.dart.weak.modular.expect
@@ -0,0 +1,70 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Base extends core::Object {
+  synthetic constructor •() → self::Base*
+    : super core::Object::•()
+    ;
+  no-such-method-forwarder set push(core::int* x) → void
+    return this.{self::Base::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[x]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C3))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder set float(covariant-by-declaration core::int* x) → void
+    return this.{self::Base::noSuchMethod}(new core::_InvocationMirror::_withType(#C4, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[x]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C3))){(core::Invocation*) →* dynamic};
+  method noSuchMethod(core::Invocation* i) → dynamic
+    return core::print("${this.{self::Base::runtimeType}{core::Type*}}: ${i.{core::Invocation::positionalArguments}{core::List<dynamic>*}.{core::List::[]}(0){(core::int*) →* dynamic}}");
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Me extends self::Base {
+  synthetic constructor •() → self::Me*
+    : super self::Base::•()
+    ;
+}
+class You extends self::Base {
+  synthetic constructor •() → self::You*
+    : super self::Base::•()
+    ;
+  no-such-method-forwarder set push(core::num* x) → void
+    return this.{self::Base::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[x]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C3))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder set float(covariant-by-declaration core::num* x) → void
+    return this.{self::Base::noSuchMethod}(new core::_InvocationMirror::_withType(#C4, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[x]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C3))){(core::Invocation*) →* dynamic};
+}
+static method main() → dynamic {
+  core::List<self::Base*>* list = <self::Base*>[new self::Me::•(), new self::You::•()];
+  for (self::Base* baba in list) {
+    baba.{self::Base::push} = 0;
+    baba.{self::Base::float} = 1;
+    if(baba is self::You*) {
+      baba{self::You*}.{self::You::push} = 2.3;
+      baba{self::You*}.{self::You::float} = 4.5;
+    }
+    try {
+      (baba as dynamic){dynamic}.push = 6.7;
+      baba is self::You* || (throw "Fail!");
+    }
+    on core::TypeError* catch(no-exception-var) {
+      baba is self::Me* || (throw "Fail!");
+    }
+    try {
+      (baba as dynamic){dynamic}.float = 8.9;
+      baba is self::You* || (throw "Fail!");
+    }
+    on core::TypeError* catch(no-exception-var) {
+      baba is self::Me* || (throw "Fail!");
+    }
+  }
+}
+
+constants  {
+  #C1 = #push=
+  #C2 = <core::Type*>[]
+  #C3 = <core::Symbol*, dynamic>{)
+  #C4 = #float=
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/abstract_override_with_different_signature.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/abstract_override_with_different_signature.dart.weak.modular.expect
new file mode 100644
index 0000000..819fb97
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/abstract_override_with_different_signature.dart.weak.modular.expect
@@ -0,0 +1,87 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Cat extends core::Object {
+  synthetic constructor •() → self::Cat*
+    : super core::Object::•()
+    ;
+  method eatFood(core::String* food) → core::bool*
+    return true;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class MockCat extends core::Object implements self::Cat {
+  synthetic constructor •() → self::MockCat*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* invocation) → dynamic {
+    dynamic arg = invocation.{core::Invocation::positionalArguments}{core::List<dynamic>*}.{core::List::[]}(0){(core::int*) →* dynamic};
+    return arg is core::String* && arg{core::String*}.{core::String::isNotEmpty}{core::bool*};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method eatFood(core::String* food) → core::bool*
+    return this.{self::MockCat::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, core::List::unmodifiable<dynamic>(<dynamic>[food]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C3))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::bool*;
+}
+class MockCat2 extends self::MockCat {
+  synthetic constructor •() → self::MockCat2*
+    : super self::MockCat::•()
+    ;
+  abstract method noSuchMethod(core::Invocation* _) → dynamic;
+}
+class MockCat3 extends self::MockCat2 implements self::Cat {
+  synthetic constructor •() → self::MockCat3*
+    : super self::MockCat2::•()
+    ;
+  no-such-method-forwarder method eatFood(core::String* food, {core::double* amount = #C4}) → core::bool*
+    return this.{self::MockCat2::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, core::List::unmodifiable<dynamic>(<dynamic>[food]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C5: amount}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::bool*;
+}
+class MockCat4 extends self::MockCat2 implements self::HungryCat {
+  synthetic constructor •() → self::MockCat4*
+    : super self::MockCat2::•()
+    ;
+  no-such-method-forwarder method eatFood(core::String* food, {core::double* amount = #C4, core::double* yetAnother = #C4}) → core::bool*
+    return this.{self::MockCat2::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, core::List::unmodifiable<dynamic>(<dynamic>[food]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C5: amount, #C6: yetAnother}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::bool*;
+}
+abstract class HungryCat extends core::Object {
+  synthetic constructor •() → self::HungryCat*
+    : super core::Object::•()
+    ;
+  abstract method eatFood(core::String* food, {core::double* amount = #C4, core::double* yetAnother = #C4}) → core::bool*;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #eatFood
+  #C2 = <core::Type*>[]
+  #C3 = <core::Symbol*, dynamic>{)
+  #C4 = null
+  #C5 = #amount
+  #C6 = #yetAnother
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/concrete_method_over_forwarder_in_mixin_application.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/concrete_method_over_forwarder_in_mixin_application.dart.weak.modular.expect
new file mode 100644
index 0000000..701d4d2
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/concrete_method_over_forwarder_in_mixin_application.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  abstract method foo() → dynamic;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic {}
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::I {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* _) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method foo() → dynamic
+    return this.{self::B::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} dynamic;
+}
+abstract class _C&A&B = self::A with self::B /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_C&A&B*
+    : super self::A::•()
+    ;
+  mixin-super-stub method noSuchMethod(core::Invocation* _) → dynamic
+    return super.{self::B::noSuchMethod}(_);
+}
+class C extends self::_C&A&B {
+  synthetic constructor •() → self::C*
+    : super self::_C&A&B::•()
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/default_argument_values.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/default_argument_values.dart.weak.modular.expect
new file mode 100644
index 0000000..bde35bd
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/default_argument_values.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic {
+    if(i.{core::Invocation::memberName}{core::Symbol*} =={core::Symbol::==}{(core::Object*) →* core::bool*} #C1) {
+      return i.{core::Invocation::namedArguments}{core::Map<core::Symbol*, dynamic>*}.{core::Map::[]}(#C2){(core::Object*) →* dynamic};
+    }
+    else
+      if(i.{core::Invocation::memberName}{core::Symbol*} =={core::Symbol::==}{(core::Object*) →* core::bool*} #C3) {
+        return i.{core::Invocation::positionalArguments}{core::List<dynamic>*}.{core::List::[]}(0){(core::int*) →* dynamic};
+      }
+    return null;
+  }
+  abstract method foo({core::String* bar = #C4}) → core::String*;
+  abstract method hest([core::int* fisk = #C5]) → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  no-such-method-forwarder method foo({core::String* bar = #C4}) → core::String*
+    return this.{self::A::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C6, #C7, core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C2: bar}))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::String*;
+  no-such-method-forwarder method hest([core::int* fisk = #C5]) → core::int*
+    return this.{self::A::noSuchMethod}(new core::_InvocationMirror::_withType(#C3, 0, #C6, core::List::unmodifiable<dynamic>(<dynamic>[fisk]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C8))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::int*;
+}
+static method main() → dynamic {
+  self::B* b = new self::B::•();
+  dynamic value;
+  if(!((value = b.{self::A::foo}(){({bar: core::String*}) →* core::String*}) =={core::String::==}{(core::Object*) →* core::bool*} "baz")) {
+    throw "Unexpected value: '${value}'; expected 'baz'.";
+  }
+  if(!((value = b.{self::A::hest}(){([core::int*]) →* core::int*}) =={core::num::==}{(core::Object*) →* core::bool*} 42)) {
+    throw "Unexpected value: '${value}'; expected '42'.";
+  }
+}
+
+constants  {
+  #C1 = #foo
+  #C2 = #bar
+  #C3 = #hest
+  #C4 = "baz"
+  #C5 = 42
+  #C6 = <core::Type*>[]
+  #C7 = <dynamic>[]
+  #C8 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/duplicated_abstract_method.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/duplicated_abstract_method.dart.weak.modular.expect
new file mode 100644
index 0000000..d8b80bb
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/duplicated_abstract_method.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class I1 extends core::Object {
+  synthetic constructor •() → self::I1*
+    : super core::Object::•()
+    ;
+  abstract method foo() → void;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I2 extends core::Object {
+  synthetic constructor •() → self::I2*
+    : super core::Object::•()
+    ;
+  abstract method foo() → void;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M extends core::Object implements self::I1, self::I2 {
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method foo() → void
+    return this.{self::M::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/forwarder_propagation.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/forwarder_propagation.dart.weak.modular.expect
new file mode 100644
index 0000000..9966f87
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/forwarder_propagation.dart.weak.modular.expect
@@ -0,0 +1,123 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "forwarder_propagation_lib.dart" as for;
+
+import "org-dartlang-testcase:///forwarder_propagation_lib.dart";
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract set foo(core::int* value) → void;
+  abstract get bar() → core::int*;
+  abstract method baz(core::int* x, {core::String* y = #C1, core::double* z = #C1}) → void;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::A {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* _) → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder get bar() → core::int*
+    return this.{self::B::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::int*;
+  no-such-method-forwarder method baz(core::int* x, {core::String* y = #C1, core::double* z = #C1}) → void
+    return this.{self::B::noSuchMethod}(new core::_InvocationMirror::_withType(#C6, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[x]), core::Map::unmodifiable<core::Symbol*, dynamic>(<core::Symbol*, dynamic>{#C7: y, #C8: z}))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder set foo(core::int* value) → void
+    return this.{self::B::noSuchMethod}(new core::_InvocationMirror::_withType(#C9, 2, #C3, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation*) →* dynamic};
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+class E extends core::Object implements for::D {
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder get /* from org-dartlang-testcase:///forwarder_propagation_lib.dart */ _privateGetter() → core::int*
+    return this.{self::E::noSuchMethod}(new core::_InvocationMirror::_withType(#C10, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::int*;
+  no-such-method-forwarder get /* from org-dartlang-testcase:///forwarder_propagation_lib.dart */ _privateField() → core::int*
+    return this.{self::E::noSuchMethod}(new core::_InvocationMirror::_withType(#C11, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::int*;
+  no-such-method-forwarder method /* from org-dartlang-testcase:///forwarder_propagation_lib.dart */ _privateMethod() → void
+    return this.{self::E::noSuchMethod}(new core::_InvocationMirror::_withType(#C12, 0, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder set /* from org-dartlang-testcase:///forwarder_propagation_lib.dart */ _privateSetter(core::int* value) → void
+    return this.{self::E::noSuchMethod}(new core::_InvocationMirror::_withType(#C13, 2, #C3, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation*) →* dynamic};
+  no-such-method-forwarder set /* from org-dartlang-testcase:///forwarder_propagation_lib.dart */ _privateField(core::int* value) → void
+    return this.{self::E::noSuchMethod}(new core::_InvocationMirror::_withType(#C14, 2, #C3, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation*) →* dynamic};
+}
+class F extends self::E {
+  synthetic constructor •() → self::F*
+    : super self::E::•()
+    ;
+}
+static method main() → dynamic {}
+
+library;
+import self as for;
+import "dart:core" as core;
+
+abstract class D extends core::Object {
+  field core::int* _privateField = null;
+  synthetic constructor •() → for::D*
+    : super core::Object::•()
+    ;
+  abstract get _privateGetter() → core::int*;
+  abstract set _privateSetter(core::int* value) → void;
+  abstract method _privateMethod() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+constants  {
+  #C1 = null
+  #C2 = #bar
+  #C3 = <core::Type*>[]
+  #C4 = <dynamic>[]
+  #C5 = <core::Symbol*, dynamic>{)
+  #C6 = #baz
+  #C7 = #y
+  #C8 = #z
+  #C9 = #foo=
+  #C10 = #org-dartlang-testcase:///forwarder_propagation.dart::_privateGetter
+  #C11 = #org-dartlang-testcase:///forwarder_propagation.dart::_privateField
+  #C12 = #org-dartlang-testcase:///forwarder_propagation.dart::_privateMethod
+  #C13 = #org-dartlang-testcase:///forwarder_propagation.dart::_privateSetter=
+  #C14 = #org-dartlang-testcase:///forwarder_propagation.dart::_privateField=
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/forwarders_not_assumed_from_mixin.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/forwarders_not_assumed_from_mixin.dart.weak.modular.expect
new file mode 100644
index 0000000..ae8492b
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/forwarders_not_assumed_from_mixin.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  abstract method foo() → void;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends core::Object implements self::I {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder method foo() → void
+    return this.{self::A::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+abstract class _B&Object&A = core::Object with self::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_B&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method noSuchMethod(core::Invocation* i) → dynamic
+    return super.{self::A::noSuchMethod}(i);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::_B&Object&A {
+  synthetic constructor •() → self::B*
+    : super self::_B&Object&A::•()
+    ;
+  no-such-method-forwarder method foo() → void
+    return this.{self::_B&Object&A::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/interface_with_concrete.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/interface_with_concrete.dart.weak.modular.expect
new file mode 100644
index 0000000..fc7e726
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/interface_with_concrete.dart.weak.modular.expect
@@ -0,0 +1,52 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic {
+    return null;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  method foo() → void {}
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A implements self::I {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  no-such-method-forwarder method foo() → void
+    return this.{self::A::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/interface_with_nsm.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/interface_with_nsm.dart.weak.modular.expect
new file mode 100644
index 0000000..6d19094
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/interface_with_nsm.dart.weak.modular.expect
@@ -0,0 +1,92 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic
+    return null;
+  no-such-method-forwarder method foo() → void
+    return this.{self::I::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M extends core::Object {
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _A&Object&M = core::Object with self::M /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_A&Object&M*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method noSuchMethod(core::Invocation* i) → dynamic
+    return super.{self::M::noSuchMethod}(i);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends self::_A&Object&M implements self::I {
+  synthetic constructor •() → self::A*
+    : super self::_A&Object&M::•()
+    ;
+  no-such-method-forwarder method foo() → void
+    return this.{self::_A&Object&M::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+abstract class _B&Object&M = core::Object with self::M /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_B&Object&M*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method noSuchMethod(core::Invocation* i) → dynamic
+    return super.{self::M::noSuchMethod}(i);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::_B&Object&M implements self::I {
+  synthetic constructor •() → self::B*
+    : super self::_B&Object&M::•()
+    ;
+  no-such-method-forwarder method foo() → void
+    return this.{self::_B&Object&M::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/multiple_abstract_setters.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/multiple_abstract_setters.dart.weak.modular.expect
new file mode 100644
index 0000000..8c67697
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/multiple_abstract_setters.dart.weak.modular.expect
@@ -0,0 +1,87 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  set foo(core::int* value) → void {}
+  get bar() → core::int*
+    return null;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  set foo(core::double* value) → void {}
+  get bar() → core::double*
+    return null;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  set foo(core::num* value) → void {}
+  get bar() → Null
+    return null;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends core::Object implements self::C, self::A, self::B {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* _) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+  no-such-method-forwarder get bar() → Null
+    return this.{self::D::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 1, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} Null;
+  no-such-method-forwarder set foo(core::num* value) → void
+    return this.{self::D::noSuchMethod}(new core::_InvocationMirror::_withType(#C5, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #bar
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+  #C5 = #foo=
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/no_forwarders_for_abstract_classes.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/no_forwarders_for_abstract_classes.dart.weak.modular.expect
new file mode 100644
index 0000000..d2fa4dd
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/no_forwarders_for_abstract_classes.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic
+    return null;
+  abstract method foo() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  no-such-method-forwarder method foo() → void
+    return this.{self::A::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/no_forwarders_for_abstract_classes_chain.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/no_forwarders_for_abstract_classes_chain.dart.weak.modular.expect
new file mode 100644
index 0000000..c2f527e
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/no_forwarders_for_abstract_classes_chain.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic
+    return null;
+  abstract method foo() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  no-such-method-forwarder method foo() → void
+    return this.{self::A::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/nsm_inherited.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/nsm_inherited.dart.weak.modular.expect
new file mode 100644
index 0000000..fadd73d
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/nsm_inherited.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class M extends core::Object {
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends self::M {
+  synthetic constructor •() → self::A*
+    : super self::M::•()
+    ;
+  no-such-method-forwarder method call(core::String* s) → void
+    return this.{self::M::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, core::List::unmodifiable<dynamic>(<dynamic>[s]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C3))){(core::Invocation*) →* dynamic};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #call
+  #C2 = <core::Type*>[]
+  #C3 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/nsm_mixed_in.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/nsm_mixed_in.dart.weak.modular.expect
new file mode 100644
index 0000000..a59d331
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/nsm_mixed_in.dart.weak.modular.expect
@@ -0,0 +1,52 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic {
+    return null;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _B&Object&A = core::Object with self::A /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_B&Object&A*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method noSuchMethod(core::Invocation* i) → dynamic
+    return super.{self::A::noSuchMethod}(i);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::_B&Object&A {
+  synthetic constructor •() → self::B*
+    : super self::_B&Object&A::•()
+    ;
+  no-such-method-forwarder method foo() → void
+    return this.{self::_B&Object&A::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/private.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/private.dart.weak.modular.expect
new file mode 100644
index 0000000..00429c3
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/private.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library private;
+import self as self;
+import "dart:core" as core;
+import "private_module.dart" as pri;
+
+import "org-dartlang-testcase:///private_module.dart" show Fisk;
+
+abstract class Foo extends core::Object {
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return 42;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar extends self::Foo implements pri::Fisk {
+  synthetic constructor •() → self::Bar*
+    : super self::Foo::•()
+    ;
+  no-such-method-forwarder method /* from org-dartlang-testcase:///private_module.dart */ _hest() → void
+    return this.{self::Foo::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+class Baz extends self::Foo implements pri::Fisk {
+  synthetic constructor •() → self::Baz*
+    : super self::Foo::•()
+    ;
+  method _hest() → dynamic
+    return null;
+  no-such-method-forwarder method /* from org-dartlang-testcase:///private_module.dart */ _hest() → void
+    return this.{self::Foo::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+static method main() → dynamic {}
+
+library private_module;
+import self as pri;
+import "dart:core" as core;
+
+abstract class Fisk extends core::Object {
+  synthetic constructor •() → pri::Fisk*
+    : super core::Object::•()
+    ;
+  abstract method _hest() → void;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #org-dartlang-testcase:///private.dart::_hest
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/private_module.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/private_module.dart.weak.modular.expect
new file mode 100644
index 0000000..1be321b
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/private_module.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library private_module;
+import self as self;
+import "dart:core" as core;
+
+abstract class Fisk extends core::Object {
+  synthetic constructor •() → self::Fisk*
+    : super core::Object::•()
+    ;
+  abstract method _hest() → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/private_same.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/private_same.dart.weak.modular.expect
new file mode 100644
index 0000000..3a2ae93
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/private_same.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class Foo extends core::Object {
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract method _foo() → void;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar extends self::Foo {
+  synthetic constructor •() → self::Bar*
+    : super self::Foo::•()
+    ;
+  method noSuchMethod(core::Invocation* invocation) → dynamic
+    return null;
+  no-such-method-forwarder method _foo() → void
+    return this.{self::Bar::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #org-dartlang-testcase:///private_same.dart::_foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/same.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/same.dart.weak.modular.expect
new file mode 100644
index 0000000..51c933a
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/same.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic {
+    return null;
+  }
+  no-such-method-forwarder method foo() → void
+    return this.{self::A::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/setter_not_shadowed_by_method.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/setter_not_shadowed_by_method.dart.weak.modular.expect
new file mode 100644
index 0000000..8a8122f
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/setter_not_shadowed_by_method.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/no_such_method_forwarders/setter_not_shadowed_by_method.dart:12:12: Error: 'foo' is already declared in this scope.
+//   void set foo(int x);
+//            ^^^
+// pkg/front_end/testcases/no_such_method_forwarders/setter_not_shadowed_by_method.dart:10:8: Context: Previous declaration of 'foo'.
+//   void foo(int x) {}
+//        ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method foo(core::int* x) → void {}
+  no-such-method-forwarder set foo(core::int* x) → void
+    return this.{self::A::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 2, #C2, core::List::unmodifiable<dynamic>(<dynamic>[x]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C3))){(core::Invocation*) →* dynamic};
+  method noSuchMethod(core::Invocation* i) → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #foo=
+  #C2 = <core::Type*>[]
+  #C3 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/no_such_method_forwarders/subst_on_forwarder.dart.weak.modular.expect b/pkg/front_end/testcases/no_such_method_forwarders/subst_on_forwarder.dart.weak.modular.expect
new file mode 100644
index 0000000..8314ecf
--- /dev/null
+++ b/pkg/front_end/testcases/no_such_method_forwarders/subst_on_forwarder.dart.weak.modular.expect
@@ -0,0 +1,68 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class I<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::T*>*
+    : super core::Object::•()
+    ;
+  abstract method foo() → self::I::T*;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M extends core::Object {
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic {
+    return null;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _A&Object&M = core::Object with self::M /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_A&Object&M*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method noSuchMethod(core::Invocation* i) → dynamic
+    return super.{self::M::noSuchMethod}(i);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends self::_A&Object&M implements self::I<core::int*> {
+  synthetic constructor •() → self::A*
+    : super self::_A&Object&M::•()
+    ;
+  no-such-method-forwarder method foo() → core::int*
+    return this.{self::_A&Object&M::noSuchMethod}(new core::_InvocationMirror::_withType(#C1, 0, #C2, #C3, core::Map::unmodifiable<core::Symbol*, dynamic>(#C4))){(core::Invocation*) →* dynamic} as{TypeError,ForDynamic} core::int*;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = #foo
+  #C2 = <core::Type*>[]
+  #C3 = <dynamic>[]
+  #C4 = <core::Symbol*, dynamic>{)
+}
diff --git a/pkg/front_end/testcases/none/equals.dart.weak.modular.expect b/pkg/front_end/testcases/none/equals.dart.weak.modular.expect
new file mode 100644
index 0000000..7950f55
--- /dev/null
+++ b/pkg/front_end/testcases/none/equals.dart.weak.modular.expect
@@ -0,0 +1,483 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/none/equals.dart:115:26: Error: Too few positional arguments: 1 required, 0 given.
+//   nonNullableClass.method() == null;
+//                          ^
+//
+// pkg/front_end/testcases/none/equals.dart:116:26: Error: Too few positional arguments: 1 required, 0 given.
+//   nonNullableClass.method() != null;
+//                          ^
+//
+// pkg/front_end/testcases/none/equals.dart:117:34: Error: Too few positional arguments: 1 required, 0 given.
+//   null == nonNullableClass.method();
+//                                  ^
+//
+// pkg/front_end/testcases/none/equals.dart:118:34: Error: Too few positional arguments: 1 required, 0 given.
+//   null != nonNullableClass.method();
+//                                  ^
+//
+// pkg/front_end/testcases/none/equals.dart:134:23: Error: The argument type 'Object?' can't be assigned to the parameter type 'Class<String>?'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+//   nonNullableClass == nullValue;
+//                       ^
+//
+// pkg/front_end/testcases/none/equals.dart:135:23: Error: The argument type 'Object?' can't be assigned to the parameter type 'Class<String>?'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+//   nonNullableClass != nullValue;
+//                       ^
+//
+// pkg/front_end/testcases/none/equals.dart:139:20: Error: The argument type 'Object?' can't be assigned to the parameter type 'Class<String>?'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+//   nullableClass == nullValue;
+//                    ^
+//
+// pkg/front_end/testcases/none/equals.dart:140:20: Error: The argument type 'Object?' can't be assigned to the parameter type 'Class<String>?'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+//   nullableClass != nullValue;
+//                    ^
+//
+// pkg/front_end/testcases/none/equals.dart:204:26: Error: Too few positional arguments: 1 required, 0 given.
+//   nonNullableClass.method() == nullValue;
+//                          ^
+//
+// pkg/front_end/testcases/none/equals.dart:205:26: Error: Too few positional arguments: 1 required, 0 given.
+//   nonNullableClass.method() != nullValue;
+//                          ^
+//
+// pkg/front_end/testcases/none/equals.dart:206:39: Error: Too few positional arguments: 1 required, 0 given.
+//   nullValue == nonNullableClass.method();
+//                                       ^
+//
+// pkg/front_end/testcases/none/equals.dart:207:39: Error: Too few positional arguments: 1 required, 0 given.
+//   nullValue != nonNullableClass.method();
+//                                       ^
+//
+// pkg/front_end/testcases/none/equals.dart:233:23: Error: The argument type 'Object' can't be assigned to the parameter type 'Class<String>?'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+//   nonNullableClass == o;
+//                       ^
+//
+// pkg/front_end/testcases/none/equals.dart:234:23: Error: The argument type 'Object' can't be assigned to the parameter type 'Class<String>?'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+//   nonNullableClass != o;
+//                       ^
+//
+// pkg/front_end/testcases/none/equals.dart:242:20: Error: The argument type 'Object' can't be assigned to the parameter type 'Class<String>?'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+//   nullableClass == o;
+//                    ^
+//
+// pkg/front_end/testcases/none/equals.dart:243:20: Error: The argument type 'Object' can't be assigned to the parameter type 'Class<String>?'.
+//  - 'Object' is from 'dart:core'.
+//  - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+//   nullableClass != o;
+//                    ^
+//
+// pkg/front_end/testcases/none/equals.dart:355:26: Error: Too few positional arguments: 1 required, 0 given.
+//   nonNullableClass.method() == nullTypedValue;
+//                          ^
+//
+// pkg/front_end/testcases/none/equals.dart:356:26: Error: Too few positional arguments: 1 required, 0 given.
+//   nonNullableClass.method() != nullTypedValue;
+//                          ^
+//
+// pkg/front_end/testcases/none/equals.dart:357:44: Error: Too few positional arguments: 1 required, 0 given.
+//   nullTypedValue == nonNullableClass.method();
+//                                            ^
+//
+// pkg/front_end/testcases/none/equals.dart:358:44: Error: Too few positional arguments: 1 required, 0 given.
+//   nullTypedValue != nonNullableClass.method();
+//                                            ^
+//
+// pkg/front_end/testcases/none/equals.dart:359:26: Error: Too few positional arguments: 1 required, 0 given.
+//   nonNullableClass.method() == o;
+//                          ^
+//
+// pkg/front_end/testcases/none/equals.dart:360:26: Error: Too few positional arguments: 1 required, 0 given.
+//   nonNullableClass.method() != o;
+//                          ^
+//
+// pkg/front_end/testcases/none/equals.dart:361:31: Error: Too few positional arguments: 1 required, 0 given.
+//   o == nonNullableClass.method();
+//                               ^
+//
+// pkg/front_end/testcases/none/equals.dart:362:31: Error: Too few positional arguments: 1 required, 0 given.
+//   o != nonNullableClass.method();
+//                               ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  operator ==(covariant-by-declaration covariant-by-class self::Class<self::Class::T%> other) → core::bool
+    return true;
+  method method(dynamic o) → dynamic {}
+}
+static const field core::Object? nullValue = #C1;
+static method test<T1 extends core::Function, T2 extends (core::int) → core::int>(core::Object o, core::Object nonNullableObject, core::Object? nullableObject, self::Class<core::String> nonNullableClass, self::Class<core::String>? nullableClass, dynamic dyn, Never never, Never? nullableNever, Null nullTypedValue, core::Function nonNullableFunction, core::Function? nullableFunction, (core::int) → core::int nonNullableFunctionType, (core::int) →? core::int nullableFunctionType, self::test::T1 nonNullableTypeVariable1, self::test::T1? nullableTypeVariable1, self::test::T2 nonNullableTypeVariable2, self::test::T2? nullableTypeVariable2) → dynamic {
+  core::print("EqualsNull (literal null)");
+  null == null;
+  !(null == null);
+  nonNullableObject == null;
+  !(nonNullableObject == null);
+  nonNullableObject == null;
+  !(nonNullableObject == null);
+  nullableObject == null;
+  !(nullableObject == null);
+  nullableObject == null;
+  !(nullableObject == null);
+  nullableClass == null;
+  !(nullableClass == null);
+  nullableClass == null;
+  !(nullableClass == null);
+  nonNullableClass == null;
+  !(nonNullableClass == null);
+  nonNullableClass == null;
+  !(nonNullableClass == null);
+  dyn == null;
+  !(dyn == null);
+  dyn == null;
+  !(dyn == null);
+  (let final Never #t1 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) == null;
+  !((let final Never #t2 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) == null);
+  (let final Never #t3 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) == null;
+  !((let final Never #t4 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) == null);
+  nullableNever == null;
+  !(nullableNever == null);
+  nullableNever == null;
+  !(nullableNever == null);
+  nullTypedValue == null;
+  !(nullTypedValue == null);
+  nullTypedValue == null;
+  !(nullTypedValue == null);
+  nonNullableFunction == null;
+  !(nonNullableFunction == null);
+  nonNullableFunction == null;
+  !(nonNullableFunction == null);
+  nullableFunction == null;
+  !(nullableFunction == null);
+  nullableFunction == null;
+  !(nullableFunction == null);
+  nonNullableFunctionType == null;
+  !(nonNullableFunctionType == null);
+  nonNullableFunctionType == null;
+  !(nonNullableFunctionType == null);
+  nullableFunctionType == null;
+  !(nullableFunctionType == null);
+  nullableFunctionType == null;
+  !(nullableFunctionType == null);
+  nonNullableTypeVariable1 == null;
+  !(nonNullableTypeVariable1 == null);
+  nonNullableTypeVariable1 == null;
+  !(nonNullableTypeVariable1 == null);
+  nullableTypeVariable1 == null;
+  !(nullableTypeVariable1 == null);
+  nullableTypeVariable1 == null;
+  !(nullableTypeVariable1 == null);
+  nonNullableTypeVariable2 == null;
+  !(nonNullableTypeVariable2 == null);
+  nonNullableTypeVariable2 == null;
+  !(nonNullableTypeVariable2 == null);
+  nullableTypeVariable2 == null;
+  !(nullableTypeVariable2 == null);
+  nullableTypeVariable2 == null;
+  !(nullableTypeVariable2 == null);
+  invalid-expression "pkg/front_end/testcases/none/equals.dart:115:26: Error: Too few positional arguments: 1 required, 0 given.
+  nonNullableClass.method() == null;
+                         ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type} == null;
+  !(invalid-expression "pkg/front_end/testcases/none/equals.dart:116:26: Error: Too few positional arguments: 1 required, 0 given.
+  nonNullableClass.method() != null;
+                         ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type} == null);
+  invalid-expression "pkg/front_end/testcases/none/equals.dart:117:34: Error: Too few positional arguments: 1 required, 0 given.
+  null == nonNullableClass.method();
+                                 ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type} == null;
+  !(invalid-expression "pkg/front_end/testcases/none/equals.dart:118:34: Error: Too few positional arguments: 1 required, 0 given.
+  null != nonNullableClass.method();
+                                 ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type} == null);
+  core::print("EqualsNull (constant null)");
+  #C1 == null;
+  !(#C1 == null);
+  nonNullableObject == null;
+  !(nonNullableObject == null);
+  nonNullableObject == null;
+  !(nonNullableObject == null);
+  nullableObject == null;
+  !(nullableObject == null);
+  nullableObject == null;
+  !(nullableObject == null);
+  nonNullableClass =={self::Class::==}{(self::Class<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/none/equals.dart:134:23: Error: The argument type 'Object?' can't be assigned to the parameter type 'Class<String>?'.
+ - 'Object' is from 'dart:core'.
+ - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+  nonNullableClass == nullValue;
+                      ^" in #C1 as{TypeError,ForNonNullableByDefault} self::Class<core::String>?;
+  !(nonNullableClass =={self::Class::==}{(self::Class<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/none/equals.dart:135:23: Error: The argument type 'Object?' can't be assigned to the parameter type 'Class<String>?'.
+ - 'Object' is from 'dart:core'.
+ - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+  nonNullableClass != nullValue;
+                      ^" in #C1 as{TypeError,ForNonNullableByDefault} self::Class<core::String>?);
+  nonNullableClass == null;
+  !(nonNullableClass == null);
+  nullableClass =={self::Class::==}{(self::Class<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/none/equals.dart:139:20: Error: The argument type 'Object?' can't be assigned to the parameter type 'Class<String>?'.
+ - 'Object' is from 'dart:core'.
+ - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+  nullableClass == nullValue;
+                   ^" in #C1 as{TypeError,ForNonNullableByDefault} self::Class<core::String>?;
+  !(nullableClass =={self::Class::==}{(self::Class<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/none/equals.dart:140:20: Error: The argument type 'Object?' can't be assigned to the parameter type 'Class<String>?'.
+ - 'Object' is from 'dart:core'.
+ - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+  nullableClass != nullValue;
+                   ^" in #C1 as{TypeError,ForNonNullableByDefault} self::Class<core::String>?);
+  nullableClass == null;
+  !(nullableClass == null);
+  dyn == null;
+  !(dyn == null);
+  dyn == null;
+  !(dyn == null);
+  let final Never #t5 = (let final Never #t6 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) == null in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never #t7 = !((let final Never #t8 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) == null) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  (let final Never #t9 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) == null;
+  !((let final Never #t10 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) == null);
+  nullableNever == null;
+  !(nullableNever == null);
+  nullableNever == null;
+  !(nullableNever == null);
+  nullTypedValue == null;
+  !(nullTypedValue == null);
+  nullTypedValue == null;
+  !(nullTypedValue == null);
+  nonNullableFunction == null;
+  !(nonNullableFunction == null);
+  nonNullableFunction == null;
+  !(nonNullableFunction == null);
+  nullableFunction == null;
+  !(nullableFunction == null);
+  nullableFunction == null;
+  !(nullableFunction == null);
+  nonNullableFunctionType == null;
+  !(nonNullableFunctionType == null);
+  nonNullableFunctionType == null;
+  !(nonNullableFunctionType == null);
+  nullableFunctionType == null;
+  !(nullableFunctionType == null);
+  nullableFunctionType == null;
+  !(nullableFunctionType == null);
+  nonNullableTypeVariable1 == null;
+  !(nonNullableTypeVariable1 == null);
+  nonNullableTypeVariable1 == null;
+  !(nonNullableTypeVariable1 == null);
+  nullableTypeVariable1 == null;
+  !(nullableTypeVariable1 == null);
+  nullableTypeVariable1 == null;
+  !(nullableTypeVariable1 == null);
+  nonNullableTypeVariable2 == null;
+  !(nonNullableTypeVariable2 == null);
+  nonNullableTypeVariable2 == null;
+  !(nonNullableTypeVariable2 == null);
+  nullableTypeVariable2 == null;
+  !(nullableTypeVariable2 == null);
+  nullableTypeVariable2 == null;
+  !(nullableTypeVariable2 == null);
+  invalid-expression "pkg/front_end/testcases/none/equals.dart:204:26: Error: Too few positional arguments: 1 required, 0 given.
+  nonNullableClass.method() == nullValue;
+                         ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type} == null;
+  !(invalid-expression "pkg/front_end/testcases/none/equals.dart:205:26: Error: Too few positional arguments: 1 required, 0 given.
+  nonNullableClass.method() != nullValue;
+                         ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type} == null);
+  invalid-expression "pkg/front_end/testcases/none/equals.dart:206:39: Error: Too few positional arguments: 1 required, 0 given.
+  nullValue == nonNullableClass.method();
+                                      ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type} == null;
+  !(invalid-expression "pkg/front_end/testcases/none/equals.dart:207:39: Error: Too few positional arguments: 1 required, 0 given.
+  nullValue != nonNullableClass.method();
+                                      ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type} == null);
+  core::print("EqualsCall");
+  nonNullableObject =={core::Object::==}{(core::Object) → core::bool} nullTypedValue;
+  !(nonNullableObject =={core::Object::==}{(core::Object) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nonNullableObject;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nonNullableObject);
+  nonNullableObject =={core::Object::==}{(core::Object) → core::bool} o;
+  !(nonNullableObject =={core::Object::==}{(core::Object) → core::bool} o);
+  o =={core::Object::==}{(core::Object) → core::bool} nonNullableObject;
+  !(o =={core::Object::==}{(core::Object) → core::bool} nonNullableObject);
+  nullableObject =={core::Object::==}{(core::Object) → core::bool} nullTypedValue;
+  !(nullableObject =={core::Object::==}{(core::Object) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullableObject;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullableObject);
+  nullableObject =={core::Object::==}{(core::Object) → core::bool} o;
+  !(nullableObject =={core::Object::==}{(core::Object) → core::bool} o);
+  o =={core::Object::==}{(core::Object) → core::bool} nullableObject;
+  !(o =={core::Object::==}{(core::Object) → core::bool} nullableObject);
+  nonNullableClass =={self::Class::==}{(self::Class<core::String>) → core::bool} nullTypedValue;
+  !(nonNullableClass =={self::Class::==}{(self::Class<core::String>) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nonNullableClass;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nonNullableClass);
+  nonNullableClass =={self::Class::==}{(self::Class<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/none/equals.dart:233:23: Error: The argument type 'Object' can't be assigned to the parameter type 'Class<String>?'.
+ - 'Object' is from 'dart:core'.
+ - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+  nonNullableClass == o;
+                      ^" in o as{TypeError,ForNonNullableByDefault} self::Class<core::String>?;
+  !(nonNullableClass =={self::Class::==}{(self::Class<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/none/equals.dart:234:23: Error: The argument type 'Object' can't be assigned to the parameter type 'Class<String>?'.
+ - 'Object' is from 'dart:core'.
+ - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+  nonNullableClass != o;
+                      ^" in o as{TypeError,ForNonNullableByDefault} self::Class<core::String>?);
+  o =={core::Object::==}{(core::Object) → core::bool} nonNullableClass;
+  !(o =={core::Object::==}{(core::Object) → core::bool} nonNullableClass);
+  nullableClass =={self::Class::==}{(self::Class<core::String>) → core::bool} nullTypedValue;
+  !(nullableClass =={self::Class::==}{(self::Class<core::String>) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullableClass;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullableClass);
+  nullableClass =={self::Class::==}{(self::Class<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/none/equals.dart:242:20: Error: The argument type 'Object' can't be assigned to the parameter type 'Class<String>?'.
+ - 'Object' is from 'dart:core'.
+ - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+  nullableClass == o;
+                   ^" in o as{TypeError,ForNonNullableByDefault} self::Class<core::String>?;
+  !(nullableClass =={self::Class::==}{(self::Class<core::String>) → core::bool} invalid-expression "pkg/front_end/testcases/none/equals.dart:243:20: Error: The argument type 'Object' can't be assigned to the parameter type 'Class<String>?'.
+ - 'Object' is from 'dart:core'.
+ - 'Class' is from 'pkg/front_end/testcases/none/equals.dart'.
+  nullableClass != o;
+                   ^" in o as{TypeError,ForNonNullableByDefault} self::Class<core::String>?);
+  o =={core::Object::==}{(core::Object) → core::bool} nullableClass;
+  !(o =={core::Object::==}{(core::Object) → core::bool} nullableClass);
+  dyn =={core::Object::==}{(core::Object) → core::bool} nullTypedValue;
+  !(dyn =={core::Object::==}{(core::Object) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} dyn;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} dyn);
+  dyn =={core::Object::==}{(core::Object) → core::bool} o;
+  !(dyn =={core::Object::==}{(core::Object) → core::bool} o);
+  o =={core::Object::==}{(core::Object) → core::bool} dyn;
+  !(o =={core::Object::==}{(core::Object) → core::bool} dyn);
+  let final Never #t11 = (let final Never #t12 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) =={core::Object::==}{(dynamic) → Never} nullTypedValue in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never #t13 = !((let final Never #t14 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) =={core::Object::==}{(dynamic) → Never} nullTypedValue) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} (let final Never #t15 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."));
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} (let final Never #t16 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")));
+  let final Never #t17 = (let final Never #t18 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) =={core::Object::==}{(dynamic) → Never} o in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never #t19 = !((let final Never #t20 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")) =={core::Object::==}{(dynamic) → Never} o) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  o =={core::Object::==}{(core::Object) → core::bool} (let final Never #t21 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`."));
+  !(o =={core::Object::==}{(core::Object) → core::bool} (let final Never #t22 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")));
+  nullableNever =={core::Object::==}{(core::Object) → core::bool} nullTypedValue;
+  !(nullableNever =={core::Object::==}{(core::Object) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullableNever;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullableNever);
+  nullableNever =={core::Object::==}{(core::Object) → core::bool} o;
+  !(nullableNever =={core::Object::==}{(core::Object) → core::bool} o);
+  o =={core::Object::==}{(core::Object) → core::bool} nullableNever;
+  !(o =={core::Object::==}{(core::Object) → core::bool} nullableNever);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullTypedValue;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullTypedValue;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} o;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} o);
+  o =={core::Object::==}{(core::Object) → core::bool} nullTypedValue;
+  !(o =={core::Object::==}{(core::Object) → core::bool} nullTypedValue);
+  nonNullableFunction =={core::Function::==}{(core::Object) → core::bool} nullTypedValue;
+  !(nonNullableFunction =={core::Function::==}{(core::Object) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nonNullableFunction;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nonNullableFunction);
+  nonNullableFunction =={core::Function::==}{(core::Object) → core::bool} o;
+  !(nonNullableFunction =={core::Function::==}{(core::Object) → core::bool} o);
+  o =={core::Object::==}{(core::Object) → core::bool} nonNullableFunction;
+  !(o =={core::Object::==}{(core::Object) → core::bool} nonNullableFunction);
+  nullableFunction =={core::Function::==}{(core::Object) → core::bool} nullTypedValue;
+  !(nullableFunction =={core::Function::==}{(core::Object) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullableFunction;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullableFunction);
+  nullableFunction =={core::Function::==}{(core::Object) → core::bool} o;
+  !(nullableFunction =={core::Function::==}{(core::Object) → core::bool} o);
+  o =={core::Object::==}{(core::Object) → core::bool} nullableFunction;
+  !(o =={core::Object::==}{(core::Object) → core::bool} nullableFunction);
+  nonNullableFunctionType =={core::Object::==}{(core::Object) → core::bool} nullTypedValue;
+  !(nonNullableFunctionType =={core::Object::==}{(core::Object) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nonNullableFunctionType;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nonNullableFunctionType);
+  nonNullableFunctionType =={core::Object::==}{(core::Object) → core::bool} o;
+  !(nonNullableFunctionType =={core::Object::==}{(core::Object) → core::bool} o);
+  o =={core::Object::==}{(core::Object) → core::bool} nonNullableFunctionType;
+  !(o =={core::Object::==}{(core::Object) → core::bool} nonNullableFunctionType);
+  nullableFunctionType =={core::Object::==}{(core::Object) → core::bool} nullTypedValue;
+  !(nullableFunctionType =={core::Object::==}{(core::Object) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullableFunctionType;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullableFunctionType);
+  nullableFunctionType =={core::Object::==}{(core::Object) → core::bool} o;
+  !(nullableFunctionType =={core::Object::==}{(core::Object) → core::bool} o);
+  o =={core::Object::==}{(core::Object) → core::bool} nullableFunctionType;
+  !(o =={core::Object::==}{(core::Object) → core::bool} nullableFunctionType);
+  nonNullableTypeVariable1 =={core::Function::==}{(core::Object) → core::bool} nullTypedValue;
+  !(nonNullableTypeVariable1 =={core::Function::==}{(core::Object) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nonNullableTypeVariable1;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nonNullableTypeVariable1);
+  nonNullableTypeVariable1 =={core::Function::==}{(core::Object) → core::bool} o;
+  !(nonNullableTypeVariable1 =={core::Function::==}{(core::Object) → core::bool} o);
+  o =={core::Object::==}{(core::Object) → core::bool} nonNullableTypeVariable1;
+  !(o =={core::Object::==}{(core::Object) → core::bool} nonNullableTypeVariable1);
+  nullableTypeVariable1 =={core::Function::==}{(core::Object) → core::bool} nullTypedValue;
+  !(nullableTypeVariable1 =={core::Function::==}{(core::Object) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullableTypeVariable1;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullableTypeVariable1);
+  nullableTypeVariable1 =={core::Function::==}{(core::Object) → core::bool} o;
+  !(nullableTypeVariable1 =={core::Function::==}{(core::Object) → core::bool} o);
+  o =={core::Object::==}{(core::Object) → core::bool} nullableTypeVariable1;
+  !(o =={core::Object::==}{(core::Object) → core::bool} nullableTypeVariable1);
+  nonNullableTypeVariable2 =={core::Object::==}{(core::Object) → core::bool} nullTypedValue;
+  !(nonNullableTypeVariable2 =={core::Object::==}{(core::Object) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nonNullableTypeVariable2;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nonNullableTypeVariable2);
+  nonNullableTypeVariable2 =={core::Object::==}{(core::Object) → core::bool} o;
+  !(nonNullableTypeVariable2 =={core::Object::==}{(core::Object) → core::bool} o);
+  o =={core::Object::==}{(core::Object) → core::bool} nonNullableTypeVariable2;
+  !(o =={core::Object::==}{(core::Object) → core::bool} nonNullableTypeVariable2);
+  nullableTypeVariable2 =={core::Object::==}{(core::Object) → core::bool} nullTypedValue;
+  !(nullableTypeVariable2 =={core::Object::==}{(core::Object) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullableTypeVariable2;
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} nullableTypeVariable2);
+  nullableTypeVariable2 =={core::Object::==}{(core::Object) → core::bool} o;
+  !(nullableTypeVariable2 =={core::Object::==}{(core::Object) → core::bool} o);
+  o =={core::Object::==}{(core::Object) → core::bool} nullableTypeVariable2;
+  !(o =={core::Object::==}{(core::Object) → core::bool} nullableTypeVariable2);
+  invalid-expression "pkg/front_end/testcases/none/equals.dart:355:26: Error: Too few positional arguments: 1 required, 0 given.
+  nonNullableClass.method() == nullTypedValue;
+                         ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type} =={core::Object::==}{(core::Object) → core::bool} nullTypedValue;
+  !(invalid-expression "pkg/front_end/testcases/none/equals.dart:356:26: Error: Too few positional arguments: 1 required, 0 given.
+  nonNullableClass.method() != nullTypedValue;
+                         ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type} =={core::Object::==}{(core::Object) → core::bool} nullTypedValue);
+  nullTypedValue =={core::Object::==}{(core::Object) → core::bool} invalid-expression "pkg/front_end/testcases/none/equals.dart:357:44: Error: Too few positional arguments: 1 required, 0 given.
+  nullTypedValue == nonNullableClass.method();
+                                           ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type};
+  !(nullTypedValue =={core::Object::==}{(core::Object) → core::bool} invalid-expression "pkg/front_end/testcases/none/equals.dart:358:44: Error: Too few positional arguments: 1 required, 0 given.
+  nullTypedValue != nonNullableClass.method();
+                                           ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type});
+  invalid-expression "pkg/front_end/testcases/none/equals.dart:359:26: Error: Too few positional arguments: 1 required, 0 given.
+  nonNullableClass.method() == o;
+                         ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type} =={core::Object::==}{(core::Object) → core::bool} o;
+  !(invalid-expression "pkg/front_end/testcases/none/equals.dart:360:26: Error: Too few positional arguments: 1 required, 0 given.
+  nonNullableClass.method() != o;
+                         ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type} =={core::Object::==}{(core::Object) → core::bool} o);
+  o =={core::Object::==}{(core::Object) → core::bool} invalid-expression "pkg/front_end/testcases/none/equals.dart:361:31: Error: Too few positional arguments: 1 required, 0 given.
+  o == nonNullableClass.method();
+                              ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type};
+  !(o =={core::Object::==}{(core::Object) → core::bool} invalid-expression "pkg/front_end/testcases/none/equals.dart:362:31: Error: Too few positional arguments: 1 required, 0 given.
+  o != nonNullableClass.method();
+                              ^" in nonNullableClass.{self::Class::method}{<inapplicable>}.(){() → invalid-type});
+}
+static method nullEqualsIndexGet(core::Map<core::int, core::String> map) → dynamic {
+  map.{core::Map::[]}(0){(core::Object?) → core::String?} == null;
+  map.{core::Map::[]}(0){(core::Object?) → core::String?} == null;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/none/issue46003.dart.weak.modular.expect b/pkg/front_end/testcases/none/issue46003.dart.weak.modular.expect
new file mode 100644
index 0000000..cbdc1a0
--- /dev/null
+++ b/pkg/front_end/testcases/none/issue46003.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  final field () → dynamic foo;
+  constructor •(() → dynamic foo) → self::A
+    : self::A::foo = foo, super core::Object::•()
+    ;
+  method bar() → void {
+    this.{self::A::foo}{() → dynamic}(){() → dynamic};
+    () → dynamic x = this.{self::A::foo}{() → dynamic};
+    x(){() → dynamic};
+    () → void y = this.{self::A::foo}{() → dynamic};
+    y(){() → void};
+  }
+}
+static method main() → dynamic {
+  new self::A::•(() → Null {}).{self::A::bar}(){() → void};
+}
diff --git a/pkg/front_end/testcases/none/method_invocation.dart.weak.modular.expect b/pkg/front_end/testcases/none/method_invocation.dart.weak.modular.expect
new file mode 100644
index 0000000..b20ca89
--- /dev/null
+++ b/pkg/front_end/testcases/none/method_invocation.dart.weak.modular.expect
@@ -0,0 +1,297 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/none/method_invocation.dart:84:24: Error: Not a constant expression.
+//   const int call_dyn = dyn.toString(0);
+//                        ^^^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:84:28: Error: Method invocation is not a constant expression.
+//   const int call_dyn = dyn.toString(0);
+//                            ^^^^^^^^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:147:34: Error: Not a constant expression.
+//   const int call_localFunction = localFunction();
+//                                  ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:152:22: Error: Not a constant expression.
+//   const int call_f = f();
+//                      ^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:157:23: Error: Not a constant expression.
+//   const bool equals = i == j;
+//                       ^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:68:42: Error: Can't use an expression of type 'Function?' as a function because it's potentially null.
+//  - 'Function' is from 'dart:core'.
+// Try calling using ?.call instead.
+//   nonNullableClass2.nullableFunctionField();
+//                                          ^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:69:43: Error: Can't use an expression of type 'Function?' as a function because it's potentially null.
+//  - 'Function' is from 'dart:core'.
+// Try calling using ?.call instead.
+//   nonNullableClass2.nullableFunctionGetter();
+//                                           ^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:70:47: Error: Can't use an expression of type 'void Function()?' as a function because it's potentially null.
+// Try calling using ?.call instead.
+//   nonNullableClass2.nullableFunctionTypedField();
+//                                               ^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:71:48: Error: Can't use an expression of type 'void Function()?' as a function because it's potentially null.
+// Try calling using ?.call instead.
+//   nonNullableClass2.nullableFunctionTypedGetter();
+//                                                ^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:74:50: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//   nonNullableClass2.nonNullableFunctionTypedField(0);
+//                                                  ^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:75:51: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//   nonNullableClass2.nonNullableFunctionTypedGetter(0);
+//                                                   ^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:78:18: Error: Method 'method' cannot be called on 'Class1?' because it is potentially null.
+//  - 'Class1' is from 'pkg/front_end/testcases/none/method_invocation.dart'.
+// Try calling using ?. instead.
+//   nullableClass1.method(0);
+//                  ^^^^^^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:102:21: Error: The method 'unresolved' isn't defined for the class 'Class1'.
+//  - 'Class1' is from 'pkg/front_end/testcases/none/method_invocation.dart'.
+// Try correcting the name to the name of an existing method, or defining a method named 'unresolved'.
+//   nonNullableClass1.unresolved();
+//                     ^^^^^^^^^^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:105:27: Error: Too few positional arguments: 1 required, 0 given.
+//   nonNullableClass1.method();
+//                           ^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:106:26: Error: Too few positional arguments: 1 required, 0 given.
+//   nonNullableFunctionType();
+//                          ^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:132:19: Error: Can't use an expression of type 'Function?' as a function because it's potentially null.
+//  - 'Function' is from 'dart:core'.
+// Try calling using ?.call instead.
+//   nullableFunction(0);
+//                   ^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:133:20: Error: Method 'call' cannot be called on 'Function?' because it is potentially null.
+//  - 'Function' is from 'dart:core'.
+// Try calling using ?. instead.
+//   nullableFunction.call(0);
+//                    ^^^^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:134:23: Error: Can't use an expression of type 'int Function(int)?' as a function because it's potentially null.
+// Try calling using ?.call instead.
+//   nullableFunctionType(0);
+//                       ^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:135:24: Error: Method 'call' cannot be called on 'int Function(int)?' because it is potentially null.
+// Try calling using ?. instead.
+//   nullableFunctionType.call(0);
+//                        ^^^^
+//
+// pkg/front_end/testcases/none/method_invocation.dart:138:27: Error: Too few positional arguments: 1 required, 0 given.
+//   nonNullableClass1.method().method(0);
+//                           ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class1 extends core::Object {
+  synthetic constructor •() → self::Class1
+    : super core::Object::•()
+    ;
+  method method(core::int o) → core::double
+    return 0.5;
+}
+class Class2<T extends core::Object? = dynamic> extends core::Object {
+  covariant-by-class field self::Class2::T% field;
+  field core::Function nonNullableFunctionField;
+  field core::Function? nullableFunctionField = null;
+  field () → void nonNullableFunctionTypedField;
+  field () →? void nullableFunctionTypedField = null;
+  constructor •(self::Class2::T% field, core::Function nonNullableFunctionField, () → void nonNullableFunctionTypedField) → self::Class2<self::Class2::T%>
+    : self::Class2::field = field, self::Class2::nonNullableFunctionField = nonNullableFunctionField, self::Class2::nonNullableFunctionTypedField = nonNullableFunctionTypedField, super core::Object::•()
+    ;
+  method call() → self::Class2::T%
+    return this.{self::Class2::field}{self::Class2::T%};
+  method method(core::int o) → self::Class2::T%
+    return this.{self::Class2::field}{self::Class2::T%};
+  get nonNullableFunctionGetter() → core::Function
+    return this.{self::Class2::nonNullableFunctionTypedField}{() → void};
+  get nullableFunctionGetter() → core::Function?
+    return this.{self::Class2::nonNullableFunctionTypedField}{() → void};
+  get nonNullableFunctionTypedGetter() → () → void
+    return this.{self::Class2::nonNullableFunctionTypedField}{() → void};
+  get nullableFunctionTypedGetter() → () →? void
+    return this.{self::Class2::nonNullableFunctionTypedField}{() → void};
+}
+static const field core::int i = #C1;
+static const field core::int j = #C2;
+static const field core::int k = #C3;
+static method test<T1 extends core::Function, T2 extends (core::int) → core::int, T3 extends core::Object? = dynamic>(self::Class1 nonNullableClass1, self::Class1? nullableClass1, dynamic dyn, Never never, self::Class2<core::String> nonNullableClass2, self::Class2<core::String>? nullableClass2, core::Function nonNullableFunction, core::Function? nullableFunction, (core::int) → core::int nonNullableFunctionType, (core::int) →? core::int nullableFunctionType, <T extends core::Object? = dynamic>(T%) → T% genericFunctionType, self::test::T1 nonNullableTypeVariable1, self::test::T1? nullableTypeVariable1, self::test::T2 nonNullableTypeVariable2, self::test::T2? nullableTypeVariable2, self::test::T3% undeterminedTypeVariable) → dynamic {
+  core::print("InstanceInvocation");
+  nonNullableClass1.{self::Class1::method}(0){(core::int) → core::double};
+  let final self::Class1? #t1 = nullableClass1 in #t1 == null ?{core::double?} null : #t1{self::Class1}.{self::Class1::method}(0){(core::int) → core::double};
+  core::print("InstanceGet calls");
+  nonNullableClass2.{self::Class2::nonNullableFunctionField}{core::Function}();
+  nonNullableClass2.{self::Class2::nonNullableFunctionGetter}{core::Function}();
+  nonNullableClass2.{self::Class2::nonNullableFunctionTypedField}{() → void}(){() → void};
+  nonNullableClass2.{self::Class2::nonNullableFunctionTypedGetter}{() → void}(){() → void};
+  invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:68:42: Error: Can't use an expression of type 'Function?' as a function because it's potentially null.
+ - 'Function' is from 'dart:core'.
+Try calling using ?.call instead.
+  nonNullableClass2.nullableFunctionField();
+                                         ^" in nonNullableClass2.{self::Class2::nullableFunctionField}{core::Function?}{<nullable>}.();
+  invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:69:43: Error: Can't use an expression of type 'Function?' as a function because it's potentially null.
+ - 'Function' is from 'dart:core'.
+Try calling using ?.call instead.
+  nonNullableClass2.nullableFunctionGetter();
+                                          ^" in nonNullableClass2.{self::Class2::nullableFunctionGetter}{core::Function?}{<nullable>}.();
+  invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:70:47: Error: Can't use an expression of type 'void Function()?' as a function because it's potentially null.
+Try calling using ?.call instead.
+  nonNullableClass2.nullableFunctionTypedField();
+                                              ^" in nonNullableClass2.{self::Class2::nullableFunctionTypedField}{() →? void}{<nullable>}.(){() →? void};
+  invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:71:48: Error: Can't use an expression of type 'void Function()?' as a function because it's potentially null.
+Try calling using ?.call instead.
+  nonNullableClass2.nullableFunctionTypedGetter();
+                                               ^" in nonNullableClass2.{self::Class2::nullableFunctionTypedGetter}{() →? void}{<nullable>}.(){() →? void};
+  let final self::Class2<core::String> #t2 = nonNullableClass2 in let final core::int #t3 = 0 in #t2.{self::Class2::nonNullableFunctionField}{core::Function}(#t3);
+  let final self::Class2<core::String> #t4 = nonNullableClass2 in let final core::int #t5 = 0 in #t4.{self::Class2::nonNullableFunctionGetter}{core::Function}(#t5);
+  let final self::Class2<core::String> #t6 = nonNullableClass2 in let final core::int #t7 = 0 in invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:74:50: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+  nonNullableClass2.nonNullableFunctionTypedField(0);
+                                                 ^" in #t6.{self::Class2::nonNullableFunctionTypedField}{() → void}{<inapplicable>}.(#t7);
+  let final self::Class2<core::String> #t8 = nonNullableClass2 in let final core::int #t9 = 0 in invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:75:51: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+  nonNullableClass2.nonNullableFunctionTypedGetter(0);
+                                                  ^" in #t8.{self::Class2::nonNullableFunctionTypedGetter}{() → void}{<inapplicable>}.(#t9);
+  core::print("InstanceInvocation (Nullable)");
+  invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:78:18: Error: Method 'method' cannot be called on 'Class1?' because it is potentially null.
+ - 'Class1' is from 'pkg/front_end/testcases/none/method_invocation.dart'.
+Try calling using ?. instead.
+  nullableClass1.method(0);
+                 ^^^^^^" in nullableClass1.{self::Class1::method}{<nullable>}.(0){(core::int) → core::double};
+  core::print("DynamicInvocation");
+  dyn{dynamic}.method(0);
+  let final dynamic #t10 = dyn in #t10 == null ?{dynamic} null : #t10{dynamic}.method(0);
+  dyn{dynamic}.toString(0);
+  const core::int call_dyn = invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:84:28: Error: Method invocation is not a constant expression.
+  const int call_dyn = dyn.toString(0);
+                           ^^^^^^^^";
+  core::print(invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:84:28: Error: Method invocation is not a constant expression.
+  const int call_dyn = dyn.toString(0);
+                           ^^^^^^^^");
+  core::print("InstanceInvocation (Object)");
+  dyn.{core::Object::toString}(){() → core::String};
+  nullableClass1.{core::Object::toString}(){() → core::String};
+  nullableClass2.{core::Object::toString}(){() → core::String};
+  nullableFunction.{core::Object::toString}(){() → core::String};
+  nullableFunctionType.{core::Object::toString}(){() → core::String};
+  nullableTypeVariable1.{core::Object::toString}(){() → core::String};
+  nullableTypeVariable2.{core::Object::toString}(){() → core::String};
+  undeterminedTypeVariable.{core::Object::toString}(){() → core::String};
+  core::print("DynamicInvocation (Never)");
+  let final Never #t11 = (let final Never #t12 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.method(0) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never #t13 = (let final Never #t14 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.toString() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  core::print("DynamicInvocation (Unresolved)");
+  invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:102:21: Error: The method 'unresolved' isn't defined for the class 'Class1'.
+ - 'Class1' is from 'pkg/front_end/testcases/none/method_invocation.dart'.
+Try correcting the name to the name of an existing method, or defining a method named 'unresolved'.
+  nonNullableClass1.unresolved();
+                    ^^^^^^^^^^" in nonNullableClass1{<unresolved>}.unresolved();
+  core::print("DynamicInvocation (Inapplicable)");
+  invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:105:27: Error: Too few positional arguments: 1 required, 0 given.
+  nonNullableClass1.method();
+                          ^" in nonNullableClass1.{self::Class1::method}{<inapplicable>}.(){() → invalid-type};
+  invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:106:26: Error: Too few positional arguments: 1 required, 0 given.
+  nonNullableFunctionType();
+                         ^" in nonNullableFunctionType{<inapplicable>}.();
+  core::print("InstanceInvocation (generic)");
+  nonNullableClass2.{self::Class2::method}(0){(core::int) → core::String};
+  let final self::Class2<core::String>? #t15 = nullableClass2 in #t15 == null ?{core::String?} null : #t15{self::Class2<core::String>}.{self::Class2::method}(0){(core::int) → core::String};
+  nonNullableClass2.{self::Class2::call}(){() → core::String};
+  nonNullableClass2.{self::Class2::call}(){() → core::String};
+  core::print("FunctionInvocation");
+  nonNullableFunction(0);
+  nonNullableFunction(0);
+  let final core::Function? #t16 = nullableFunction in #t16 == null ?{dynamic} null : #t16{core::Function}(0);
+  nonNullableFunctionType(0){(core::int) → core::int};
+  nonNullableFunctionType(0){(core::int) → core::int};
+  let final (core::int) →? core::int #t17 = nullableFunctionType in #t17 == null ?{core::int?} null : #t17{(core::int) → core::int}(0){(core::int) → core::int};
+  genericFunctionType<core::int>(0){(core::int) → core::int};
+  genericFunctionType<core::num>(0){(core::num) → core::num};
+  core::num i = genericFunctionType<core::num>(0){(core::num) → core::num};
+  nonNullableTypeVariable1(0);
+  nonNullableTypeVariable1(0);
+  let final self::test::T1? #t18 = nullableTypeVariable1 in #t18 == null ?{dynamic} null : #t18{self::test::T1}(0);
+  nonNullableTypeVariable2(0){(core::int) → core::int};
+  nonNullableTypeVariable2(0){(core::int) → core::int};
+  let final self::test::T2? #t19 = nullableTypeVariable2 in #t19 == null ?{core::int?} null : #t19{self::test::T2}(0){(core::int) → core::int};
+  core::print("FunctionInvocation (Nullable)");
+  invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:132:19: Error: Can't use an expression of type 'Function?' as a function because it's potentially null.
+ - 'Function' is from 'dart:core'.
+Try calling using ?.call instead.
+  nullableFunction(0);
+                  ^" in nullableFunction{<nullable>}.(0);
+  invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:133:20: Error: Method 'call' cannot be called on 'Function?' because it is potentially null.
+ - 'Function' is from 'dart:core'.
+Try calling using ?. instead.
+  nullableFunction.call(0);
+                   ^^^^" in nullableFunction{<nullable>}.(0);
+  invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:134:23: Error: Can't use an expression of type 'int Function(int)?' as a function because it's potentially null.
+Try calling using ?.call instead.
+  nullableFunctionType(0);
+                      ^" in nullableFunctionType{<nullable>}.(0){(core::int) →? core::int};
+  invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:135:24: Error: Method 'call' cannot be called on 'int Function(int)?' because it is potentially null.
+Try calling using ?. instead.
+  nullableFunctionType.call(0);
+                       ^^^^" in nullableFunctionType{<nullable>}.(0){(core::int) →? core::int};
+  core::print("DynamicInvocation (Invalid)");
+  invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:138:27: Error: Too few positional arguments: 1 required, 0 given.
+  nonNullableClass1.method().method(0);
+                          ^" in nonNullableClass1.{self::Class1::method}{<inapplicable>}.(){() → invalid-type}{dynamic}.method(0);
+  core::print("LocalFunctionInvocation");
+  function localFunction() → core::int
+    return 42;
+  function genericLocalFunction<T extends core::Object? = dynamic>(T% t) → T%
+    return t;
+  localFunction(){() → core::int};
+  genericLocalFunction<core::int>(0){(core::int) → core::int};
+  genericLocalFunction<core::num>(0){(core::num) → core::num};
+  const core::int call_localFunction = invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:147:34: Error: Not a constant expression.
+  const int call_localFunction = localFunction();
+                                 ^^^^^^^^^^^^^";
+  core::print(invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:147:34: Error: Not a constant expression.
+  const int call_localFunction = localFunction();
+                                 ^^^^^^^^^^^^^");
+  () → core::int f = () → core::int => 42;
+  const core::int call_f = invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:152:22: Error: Not a constant expression.
+  const int call_f = f();
+                     ^";
+  core::print(invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:152:22: Error: Not a constant expression.
+  const int call_f = f();
+                     ^");
+  core::print(#C4);
+  const core::bool equals = invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:157:23: Error: Not a constant expression.
+  const bool equals = i == j;
+                      ^";
+  core::print(invalid-expression "pkg/front_end/testcases/none/method_invocation.dart:157:23: Error: Not a constant expression.
+  const bool equals = i == j;
+                      ^");
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 4
+  #C2 = 24
+  #C3 = 96
+  #C4 = false
+}
diff --git a/pkg/front_end/testcases/none/mixin_application_declares/main.dart.weak.modular.expect b/pkg/front_end/testcases/none/mixin_application_declares/main.dart.weak.modular.expect
new file mode 100644
index 0000000..eb12b86
--- /dev/null
+++ b/pkg/front_end/testcases/none/mixin_application_declares/main.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "main_lib.dart" as mai;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+class SubClass extends mai::Class {
+  synthetic constructor •() → self::SubClass
+    : super mai::Class::•()
+    ;
+}
+static method main() → dynamic {
+  new self::SubClass::•();
+}
diff --git a/pkg/front_end/testcases/none/mixin_covariant.dart.weak.modular.expect b/pkg/front_end/testcases/none/mixin_covariant.dart.weak.modular.expect
new file mode 100644
index 0000000..ebd8305
--- /dev/null
+++ b/pkg/front_end/testcases/none/mixin_covariant.dart.weak.modular.expect
@@ -0,0 +1,79 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Superclass extends core::Object {
+  synthetic constructor •() → self::Superclass
+    : super core::Object::•()
+    ;
+  method method1(core::num argument1, core::num argument2) → core::String
+    return "Superclass";
+  method method2(core::num argument1, core::num argument2) → core::String
+    return "Superclass";
+  method method3(core::num argument1, covariant-by-declaration core::int argument2) → core::String
+    return "Superclass";
+  method method4(core::num argument1, covariant-by-declaration core::num argument2) → core::String
+    return "Superclass";
+}
+class Mixin extends core::Object {
+  synthetic constructor •() → self::Mixin
+    : super core::Object::•()
+    ;
+  method method1(core::num argument1, core::num argument2) → core::String
+    return "Mixin";
+  method method2(covariant-by-declaration core::int argument1, core::num argument2) → core::String
+    return "Mixin";
+  method method3(core::num argument1, core::num argument2) → core::String
+    return "Mixin";
+  method method4(covariant-by-declaration core::int argument1, core::int argument2) → core::String
+    return "Mixin";
+}
+abstract class _Class&Superclass&Mixin = self::Superclass with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Class&Superclass&Mixin
+    : super self::Superclass::•()
+    ;
+  mixin-super-stub method method1(core::num argument1, core::num argument2) → core::String
+    return super.{self::Mixin::method1}(argument1, argument2);
+  mixin-super-stub method method2(covariant-by-declaration core::int argument1, core::num argument2) → core::String
+    return super.{self::Mixin::method2}(argument1, argument2);
+  forwarding-stub method method3(core::num argument1, covariant-by-declaration core::num argument2) → core::String
+    return super.{self::Mixin::method3}(argument1, argument2);
+  forwarding-stub method method4(covariant-by-declaration core::int argument1, covariant-by-declaration core::int argument2) → core::String
+    return super.{self::Mixin::method4}(argument1, argument2);
+}
+class Class extends self::_Class&Superclass&Mixin {
+  synthetic constructor •() → self::Class
+    : super self::_Class&Superclass&Mixin::•()
+    ;
+}
+static method main() → dynamic {
+  self::Class c = new self::Class::•();
+  self::expect("Mixin", c.{self::_Class&Superclass&Mixin::method1}(0, 1){(core::num, core::num) → core::String});
+  self::expect("Mixin", c.{self::_Class&Superclass&Mixin::method2}(0, 1){(core::int, core::num) → core::String});
+  self::expect("Mixin", c.{self::_Class&Superclass&Mixin::method3}(0, 1){(core::num, core::num) → core::String});
+  self::expect("Mixin", c.{self::_Class&Superclass&Mixin::method4}(0, 1){(core::int, core::int) → core::String});
+  self::Superclass s = c;
+  self::expect("Mixin", s.{self::Superclass::method1}(0.5, 1.5){(core::num, core::num) → core::String});
+  self::throws(() → void => s.{self::Superclass::method2}(0.5, 1.5){(core::num, core::num) → core::String});
+  self::expect("Mixin", s.{self::Superclass::method3}(0.5, 1){(core::num, core::int) → core::String});
+  self::throws(() → void => s.{self::Superclass::method4}(0.5, 1){(core::num, core::num) → core::String});
+  self::expect("Mixin", s.{self::Superclass::method4}(1, 0.5){(core::num, core::num) → core::String});
+  self::Mixin m = c;
+  self::expect("Mixin", m.{self::Mixin::method1}(0, 1){(core::num, core::num) → core::String});
+  self::expect("Mixin", m.{self::Mixin::method2}(0, 1){(core::int, core::num) → core::String});
+  self::expect("Mixin", m.{self::Mixin::method3}(0, 1){(core::num, core::num) → core::String});
+  self::expect("Mixin", m.{self::Mixin::method4}(0, 1){(core::int, core::int) → core::String});
+}
+static method expect(dynamic expected, dynamic actual) → void {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → void f) → void {
+  try {
+    f(){() → void};
+  }
+  on core::Object catch(final core::Object _) {
+    return;
+  }
+  throw "Expected exception";
+}
diff --git a/pkg/front_end/testcases/none/mixin_super.dart.weak.modular.expect b/pkg/front_end/testcases/none/mixin_super.dart.weak.modular.expect
new file mode 100644
index 0000000..9929e69
--- /dev/null
+++ b/pkg/front_end/testcases/none/mixin_super.dart.weak.modular.expect
@@ -0,0 +1,65 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class Diagnosticable extends core::Object /*isMixinDeclaration*/  {
+  method debugFillProperties(self::DiagnosticPropertiesBuilder properties) → void {}
+}
+class DiagnosticPropertiesBuilder extends core::Object {
+  synthetic constructor •() → self::DiagnosticPropertiesBuilder
+    : super core::Object::•()
+    ;
+}
+abstract class _PointerEvent&Object&Diagnosticable = core::Object with self::Diagnosticable /*isAnonymousMixin,hasConstConstructor*/  {
+  const synthetic constructor •() → self::_PointerEvent&Object&Diagnosticable
+    : super core::Object::•()
+    ;
+  mixin-super-stub method debugFillProperties(self::DiagnosticPropertiesBuilder properties) → void
+    return super.{self::Diagnosticable::debugFillProperties}(properties);
+}
+abstract class PointerEvent extends self::_PointerEvent&Object&Diagnosticable {
+  synthetic constructor •() → self::PointerEvent
+    : super self::_PointerEvent&Object&Diagnosticable::•()
+    ;
+}
+abstract class PointerSignalEvent extends self::PointerEvent {
+  synthetic constructor •() → self::PointerSignalEvent
+    : super self::PointerEvent::•()
+    ;
+}
+abstract class _PointerEventDescription extends self::PointerEvent /*isMixinDeclaration*/  {
+  @#C1
+  method debugFillProperties(self::DiagnosticPropertiesBuilder properties) → void {
+    super.{self::_PointerEvent&Object&Diagnosticable::debugFillProperties}(properties);
+  }
+}
+abstract class _CopyPointerScrollEvent extends self::PointerEvent /*isMixinDeclaration*/  {
+}
+abstract class _PointerScrollEvent&PointerSignalEvent&_PointerEventDescription = self::PointerSignalEvent with self::_PointerEventDescription /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_PointerScrollEvent&PointerSignalEvent&_PointerEventDescription
+    : super self::PointerSignalEvent::•()
+    ;
+  mixin-super-stub method debugFillProperties(self::DiagnosticPropertiesBuilder properties) → void
+    return super.{self::_PointerEventDescription::debugFillProperties}(properties);
+}
+abstract class _PointerScrollEvent&PointerSignalEvent&_PointerEventDescription&_CopyPointerScrollEvent = self::_PointerScrollEvent&PointerSignalEvent&_PointerEventDescription with self::_CopyPointerScrollEvent /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_PointerScrollEvent&PointerSignalEvent&_PointerEventDescription&_CopyPointerScrollEvent
+    : super self::_PointerScrollEvent&PointerSignalEvent&_PointerEventDescription::•()
+    ;
+}
+class PointerScrollEvent extends self::_PointerScrollEvent&PointerSignalEvent&_PointerEventDescription&_CopyPointerScrollEvent {
+  synthetic constructor •() → self::PointerScrollEvent
+    : super self::_PointerScrollEvent&PointerSignalEvent&_PointerEventDescription&_CopyPointerScrollEvent::•()
+    ;
+  @#C1
+  method debugFillProperties(self::DiagnosticPropertiesBuilder properties) → void {
+    super.{self::_PointerScrollEvent&PointerSignalEvent&_PointerEventDescription::debugFillProperties}(properties);
+  }
+}
+static method main() → dynamic {
+  new self::PointerScrollEvent::•().{self::PointerScrollEvent::debugFillProperties}(new self::DiagnosticPropertiesBuilder::•()){(self::DiagnosticPropertiesBuilder) → void};
+}
+
+constants  {
+  #C1 = core::_Override {}
+}
diff --git a/pkg/front_end/testcases/none/new_method_invocation_encodings.dart.weak.modular.expect b/pkg/front_end/testcases/none/new_method_invocation_encodings.dart.weak.modular.expect
new file mode 100644
index 0000000..fe8cc3c
--- /dev/null
+++ b/pkg/front_end/testcases/none/new_method_invocation_encodings.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/none/new_method_invocation_encodings.dart:7:8: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   int? getter => null;
+//        ^^^^^^
+//
+// pkg/front_end/testcases/none/new_method_invocation_encodings.dart:14:5: Error: The setter 'setter' isn't defined for the class 'Class'.
+//  - 'Class' is from 'pkg/front_end/testcases/none/new_method_invocation_encodings.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'setter'.
+//   c.setter = c.getter;
+//     ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  field core::int? field = null;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  method getter() → core::int?
+    return null;
+  method setter(core::int? value) → void {}
+  method method() → void {}
+}
+static method test(self::Class c, dynamic d, core::Function f1, () → void f2) → dynamic {
+  c.{self::Class::field} = c.{self::Class::field}{core::int?};
+  invalid-expression "pkg/front_end/testcases/none/new_method_invocation_encodings.dart:14:5: Error: The setter 'setter' isn't defined for the class 'Class'.
+ - 'Class' is from 'pkg/front_end/testcases/none/new_method_invocation_encodings.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'setter'.
+  c.setter = c.getter;
+    ^^^^^^" in c{<unresolved>}.setter = c.{self::Class::getter}{() → core::int?};
+  c.{self::Class::method}{() → void};
+  c.{self::Class::method}(){() → void};
+  d{dynamic}.field = d{dynamic}.field;
+  d{dynamic}.setter = d{dynamic}.getter;
+  d{dynamic}.method;
+  d{dynamic}.method();
+  f1();
+  f1.call;
+  f2(){() → void};
+  f2.call;
+  function local() → Null {}
+  local(){() → Null};
+  c =={core::Object::==}{(core::Object) → core::bool} d;
+  !(c =={core::Object::==}{(core::Object) → core::bool} d);
+  c == null;
+  !(c == null);
+  d == null;
+  !(d == null);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/none/operator.dart.weak.modular.expect b/pkg/front_end/testcases/none/operator.dart.weak.modular.expect
new file mode 100644
index 0000000..4de73e4
--- /dev/null
+++ b/pkg/front_end/testcases/none/operator.dart.weak.modular.expect
@@ -0,0 +1,164 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/none/operator.dart:48:10: Error: The operator '-' isn't defined for the class 'String'.
+// Try correcting the operator to an existing operator, or defining a '-' operator.
+//   string - 42;
+//          ^
+//
+// pkg/front_end/testcases/none/operator.dart:66:12: Error: Too few positional arguments: 1 required, 0 given.
+//   -c.method();
+//            ^
+//
+// pkg/front_end/testcases/none/operator.dart:69:3: Error: The operator 'unary-' isn't defined for the class 'String'.
+// Try correcting the operator to an existing operator, or defining a 'unary-' operator.
+//   -string;
+//   ^
+//
+// pkg/front_end/testcases/none/operator.dart:86:11: Error: Too few positional arguments: 1 required, 0 given.
+//   c.method()[0];
+//           ^
+//
+// pkg/front_end/testcases/none/operator.dart:109:3: Error: Undefined name 'string'.
+//   string[0] = 42;
+//   ^^^^^^
+//
+// pkg/front_end/testcases/none/operator.dart:106:11: Error: Too few positional arguments: 1 required, 0 given.
+//   c.method()[0] = 42;
+//           ^
+//
+// pkg/front_end/testcases/none/operator.dart:129:3: Error: Undefined name 'string'.
+//   string[0] += 42;
+//   ^^^^^^
+//
+// pkg/front_end/testcases/none/operator.dart:116:14: Error: Operator '+' cannot be called on 'double?' because it is potentially null.
+//   map['foo'] += 0.5;
+//              ^
+//
+// pkg/front_end/testcases/none/operator.dart:126:11: Error: Too few positional arguments: 1 required, 0 given.
+//   c.method()[0] += 42;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Class<self::Class::T%>
+    : super core::Object::•()
+    ;
+  operator +(covariant-by-class self::Class<self::Class::T%> other) → self::Class<self::Class::T%>
+    return other;
+  operator unary-() → self::Class<self::Class::T%>
+    return this;
+  operator [](core::int index) → self::Class<self::Class::T%>
+    return this;
+  operator []=(core::int index, covariant-by-class self::Class<self::Class::T%> value) → void {}
+  method method(core::double o) → core::int
+    return 42;
+}
+static method add(core::num n, core::int i, core::double d, self::Class<core::String> c, dynamic dyn, Never never, core::String string) → dynamic {
+  core::print("InstanceInvocation");
+  n.{core::num::+}(n){(core::num) → core::num};
+  n.{core::num::+}(i){(core::num) → core::num};
+  n.{core::num::+}(d){(core::num) → core::double};
+  n.{core::num::+}(dyn as{TypeError,ForDynamic,ForNonNullableByDefault} core::num){(core::num) → core::num};
+  core::print("InstanceInvocation");
+  i.{core::num::+}(n){(core::num) → core::num};
+  i.{core::num::+}(i){(core::num) → core::int};
+  i.{core::num::+}(d){(core::num) → core::double};
+  i.{core::num::+}(dyn as{TypeError,ForDynamic,ForNonNullableByDefault} core::num){(core::num) → core::num};
+  core::print("InstanceInvocation");
+  d.{core::double::+}(n){(core::num) → core::double};
+  d.{core::double::+}(i){(core::num) → core::double};
+  d.{core::double::+}(d){(core::num) → core::double};
+  i.{core::num::+}(dyn as{TypeError,ForDynamic,ForNonNullableByDefault} core::num){(core::num) → core::num};
+  core::print("InstanceInvocation");
+  c.{self::Class::+}(c){(self::Class<core::String>) → self::Class<core::String>};
+  c.{self::Class::+}(dyn as{TypeError,ForDynamic,ForNonNullableByDefault} self::Class<core::String>){(self::Class<core::String>) → self::Class<core::String>};
+  core::print("DynamicInvocation");
+  dyn{dynamic}.+(n);
+  core::print("DynamicInvocation (Never)");
+  let final Never #t1 = (let final Never #t2 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.+(n) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  core::print("DynamicInvocation (Invalid)");
+  invalid-expression "pkg/front_end/testcases/none/operator.dart:48:10: Error: The operator '-' isn't defined for the class 'String'.
+Try correcting the operator to an existing operator, or defining a '-' operator.
+  string - 42;
+         ^" in string{<unresolved>}.-(42);
+}
+static method unaryMinus(core::num n, core::int i, core::double d, self::Class<core::String> c, dynamic dyn, Never never, core::String string) → dynamic {
+  core::print("InstanceInvocation");
+  n.{core::num::unary-}(){() → core::num};
+  i.{core::int::unary-}(){() → core::int};
+  d.{core::double::unary-}(){() → core::double};
+  c.{self::Class::unary-}(){() → self::Class<core::String>};
+  core::print("DynamicInvocation");
+  dyn{dynamic}.unary-();
+  core::print("DynamicInvocation (Never)");
+  let final Never #t3 = (let final Never #t4 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.unary-() in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  core::print("DynamicInvocation (Invalid)");
+  invalid-expression "pkg/front_end/testcases/none/operator.dart:66:12: Error: Too few positional arguments: 1 required, 0 given.
+  -c.method();
+           ^" in c.{self::Class::method}{<inapplicable>}.(){() → invalid-type}{<invalid>}.unary-();
+  core::print("DynamicInvocation (Unresolved)");
+  invalid-expression "pkg/front_end/testcases/none/operator.dart:69:3: Error: The operator 'unary-' isn't defined for the class 'String'.
+Try correcting the operator to an existing operator, or defining a 'unary-' operator.
+  -string;
+  ^" in string{<unresolved>}.unary-();
+}
+static method indexGet(core::List<core::int> list, core::Map<core::String, core::double> map, self::Class<core::String> c, dynamic dyn, Never never, core::String string) → dynamic {
+  core::print("InstanceInvocation");
+  list.{core::List::[]}(0){(core::int) → core::int};
+  map.{core::Map::[]}("foo"){(core::Object?) → core::double?};
+  c.{self::Class::[]}(0){(core::int) → self::Class<core::String>};
+  core::print("DynamicInvocation");
+  dyn{dynamic}.[](0);
+  core::print("DynamicInvocation (Never)");
+  let final Never #t5 = (let final Never #t6 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.[](0) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  core::print("DynamicInvocation (Invalid)");
+  invalid-expression "pkg/front_end/testcases/none/operator.dart:86:11: Error: Too few positional arguments: 1 required, 0 given.
+  c.method()[0];
+          ^" in c.{self::Class::method}{<inapplicable>}.(){() → invalid-type}{<invalid>}.[](0);
+  core::print("DynamicInvocation (Unresolved)");
+  string.{core::String::[]}(0){(core::int) → core::String};
+}
+static method indexSet(core::List<core::int> list, core::Map<core::String, core::double> map, self::Class<core::String> c, dynamic dyn, Never never) → dynamic {
+  core::print("InstanceInvocation");
+  list.{core::List::[]=}(0, 42){(core::int, core::int) → void};
+  map.{core::Map::[]=}("foo", 0.5){(core::String, core::double) → void};
+  c.{self::Class::[]=}(0, c){(core::int, self::Class<core::String>) → void};
+  core::print("DynamicInvocation");
+  dyn{dynamic}.[]=(0, 42);
+  core::print("DynamicInvocation (Never)");
+  (let final Never #t7 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.[]=(0, 42);
+  core::print("DynamicInvocation (Invalid)");
+  invalid-expression "pkg/front_end/testcases/none/operator.dart:106:11: Error: Too few positional arguments: 1 required, 0 given.
+  c.method()[0] = 42;
+          ^" in c.{self::Class::method}{<inapplicable>}.(){() → invalid-type}{<invalid>}.[]=(0, 42);
+  core::print("DynamicInvocation (Unresolved)");
+  invalid-expression "pkg/front_end/testcases/none/operator.dart:109:3: Error: Undefined name 'string'.
+  string[0] = 42;
+  ^^^^^^"{<invalid>}.[]=(0, 42);
+}
+static method compound(core::List<core::int> list, core::Map<core::String, core::double> map, self::Class<core::String> c, dynamic dyn, Never never) → dynamic {
+  core::print("InstanceInvocation");
+  let final core::List<core::int> #t8 = list in let final core::int #t9 = 0 in #t8.{core::List::[]=}(#t9, #t8.{core::List::[]}(#t9){(core::int) → core::int}.{core::num::+}(42){(core::num) → core::int}){(core::int, core::int) → void};
+  let final core::Map<core::String, core::double> #t10 = map in let final core::String #t11 = "foo" in #t10.{core::Map::[]=}(#t11, invalid-expression "pkg/front_end/testcases/none/operator.dart:116:14: Error: Operator '+' cannot be called on 'double?' because it is potentially null.
+  map['foo'] += 0.5;
+             ^" in #t10.{core::Map::[]}(#t11){(core::Object?) → core::double?}.{core::double::+}(0.5){(core::num) → core::double}){(core::String, core::double) → void};
+  let final self::Class<core::String> #t12 = c in let final core::int #t13 = 0 in #t12.{self::Class::[]=}(#t13, #t12.{self::Class::[]}(#t13){(core::int) → self::Class<core::String>}.{self::Class::+}(c){(self::Class<core::String>) → self::Class<core::String>}){(core::int, self::Class<core::String>) → void};
+  core::print("DynamicInvocation");
+  let final dynamic #t14 = dyn in let final core::int #t15 = 0 in #t14{dynamic}.[]=(#t15, #t14{dynamic}.[](#t15){dynamic}.+(42));
+  core::print("DynamicInvocation (Never)");
+  let final Never #t16 = let final Never #t17 = let final Never #t18 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.") in let final core::int #t19 = 0 in #t17{Never}.[]=(#t19, #t17{Never}.[](#t19){Never}.+(42)) in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  core::print("DynamicInvocation (Invalid)");
+  let final invalid-type #t20 = invalid-expression "pkg/front_end/testcases/none/operator.dart:126:11: Error: Too few positional arguments: 1 required, 0 given.
+  c.method()[0] += 42;
+          ^" in c.{self::Class::method}{<inapplicable>}.(){() → invalid-type} in let final core::int #t21 = 0 in #t20{<invalid>}.[]=(#t21, #t20{<invalid>}.[](#t21){<invalid>}.+(42));
+  core::print("DynamicInvocation (Unresolved)");
+  let final invalid-type #t22 = invalid-expression "pkg/front_end/testcases/none/operator.dart:129:3: Error: Undefined name 'string'.
+  string[0] += 42;
+  ^^^^^^" in let final core::int #t23 = 0 in #t22{<invalid>}.[]=(#t23, #t22{<invalid>}.[](#t23){<invalid>}.+(42));
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/none/property_get.dart.weak.modular.expect b/pkg/front_end/testcases/none/property_get.dart.weak.modular.expect
new file mode 100644
index 0000000..20f72b6
--- /dev/null
+++ b/pkg/front_end/testcases/none/property_get.dart.weak.modular.expect
@@ -0,0 +1,150 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/none/property_get.dart:55:32: Error: Not a constant expression.
+//   const dynamic instance_get = nullableClass1.field;
+//                                ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/none/property_get.dart:63:36: Error: Not a constant expression.
+//   const dynamic instance_tearOff = nonNullableClass1.method;
+//                                    ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/none/property_get.dart:82:27: Error: Not a constant expression.
+//   const dynamic dyn_get = dyn.field;
+//                           ^^^
+//
+// pkg/front_end/testcases/none/property_get.dart:106:36: Error: Not a constant expression.
+//   const dynamic function_tearOff = nonNullableFunction.call;
+//                                    ^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/none/property_get.dart:67:18: Error: Can't tear off method 'call' from a potentially null value.
+//   Function? f2 = nullableClass2;
+//                  ^
+//
+// pkg/front_end/testcases/none/property_get.dart:110:27: Error: Too few positional arguments: 1 required, 0 given.
+//   nonNullableClass1.method().field;
+//                           ^
+//
+// pkg/front_end/testcases/none/property_get.dart:113:21: Error: The getter 'unresolved' isn't defined for the class 'Class1'.
+//  - 'Class1' is from 'pkg/front_end/testcases/none/property_get.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'unresolved'.
+//   nonNullableClass1.unresolved;
+//                     ^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class1 extends core::Object {
+  field core::int field;
+  static field core::int staticField = 42;
+  constructor •(core::int field) → self::Class1
+    : self::Class1::field = field, super core::Object::•()
+    ;
+  method method(core::double o) → core::int
+    return 0;
+  static method staticMethod(core::double o) → core::int
+    return 0;
+}
+class Class2<T extends core::Object? = dynamic> extends core::Object {
+  covariant-by-class field self::Class2::T% field;
+  constructor •(self::Class2::T% field) → self::Class2<self::Class2::T%>
+    : self::Class2::field = field, super core::Object::•()
+    ;
+  method call() → core::int
+    return 42;
+}
+static field core::int topLevelField = 42;
+static const field core::String string = #C1;
+static const field core::int stringLength = #C2;
+static const field dynamic dynamicString = #C1;
+static const field core::int dynamicStringLength = #C2;
+static method topLevelMethod(core::double o) → core::int
+  return 0;
+static method test<T1 extends core::Function, T2 extends () → core::int>(self::Class1 nonNullableClass1, self::Class1? nullableClass1, dynamic dyn, Never never, self::Class2<core::String> nonNullableClass2, self::Class2<core::String>? nullableClass2, core::Function nonNullableFunction, core::Function? nullableFunction, () → core::int nonNullableFunctionType, () →? core::int nullableFunctionType, self::test::T1 nonNullableTypeVariable1, self::test::T1? nullableTypeVariable1, self::test::T2 nonNullableTypeVariable2, self::test::T2? nullableTypeVariable2) → dynamic {
+  core::print("InstanceGet");
+  nonNullableClass1.{self::Class1::field}{core::int};
+  let final self::Class1? #t1 = nullableClass1 in #t1 == null ?{core::int?} null : #t1{self::Class1}.{self::Class1::field}{core::int};
+  nonNullableClass2.{self::Class2::field}{core::String};
+  let final self::Class2<core::String>? #t2 = nullableClass2 in #t2 == null ?{core::String?} null : #t2{self::Class2<core::String>}.{self::Class2::field}{core::String};
+  const dynamic instance_get = invalid-expression "pkg/front_end/testcases/none/property_get.dart:55:32: Error: Not a constant expression.
+  const dynamic instance_get = nullableClass1.field;
+                               ^^^^^^^^^^^^^^";
+  core::print(invalid-expression "pkg/front_end/testcases/none/property_get.dart:55:32: Error: Not a constant expression.
+  const dynamic instance_get = nullableClass1.field;
+                               ^^^^^^^^^^^^^^");
+  core::print("InstanceTearOff");
+  nonNullableClass1.{self::Class1::method}{(core::double) → core::int};
+  let final self::Class1? #t3 = nullableClass1 in #t3 == null ?{(core::double) →? core::int} null : #t3{self::Class1}.{self::Class1::method}{(core::double) → core::int};
+  nonNullableClass2.{self::Class2::call}{() → core::int};
+  let final self::Class2<core::String>? #t4 = nullableClass2 in #t4 == null ?{() →? core::int} null : #t4{self::Class2<core::String>}.{self::Class2::call}{() → core::int};
+  const dynamic instance_tearOff = invalid-expression "pkg/front_end/testcases/none/property_get.dart:63:36: Error: Not a constant expression.
+  const dynamic instance_tearOff = nonNullableClass1.method;
+                                   ^^^^^^^^^^^^^^^^^";
+  core::print(invalid-expression "pkg/front_end/testcases/none/property_get.dart:63:36: Error: Not a constant expression.
+  const dynamic instance_tearOff = nonNullableClass1.method;
+                                   ^^^^^^^^^^^^^^^^^");
+  core::Function f1 = let final self::Class2<core::String> #t5 = nonNullableClass2 in #t5 == null ?{() → core::int} null : #t5.{self::Class2::call}{() → core::int};
+  core::Function? f2 = invalid-expression "pkg/front_end/testcases/none/property_get.dart:67:18: Error: Can't tear off method 'call' from a potentially null value.
+  Function? f2 = nullableClass2;
+                 ^" in nullableClass2 as{TypeError} core::Function?;
+  core::print("StaticGet");
+  self::Class1::staticField;
+  self::topLevelField;
+  core::print("StaticTearOff");
+  #C3;
+  #C4;
+  core::print(#C4);
+  core::print("DynamicGet");
+  dyn{dynamic}.field;
+  let final dynamic #t6 = dyn in #t6 == null ?{dynamic} null : #t6{dynamic}.field;
+  const dynamic dyn_get = invalid-expression "pkg/front_end/testcases/none/property_get.dart:82:27: Error: Not a constant expression.
+  const dynamic dyn_get = dyn.field;
+                          ^^^";
+  core::print(invalid-expression "pkg/front_end/testcases/none/property_get.dart:82:27: Error: Not a constant expression.
+  const dynamic dyn_get = dyn.field;
+                          ^^^");
+  core::print("InstanceGet (Object)");
+  dyn.{core::Object::hashCode}{core::int};
+  nullableClass1.{core::Object::hashCode}{core::int};
+  core::print("InstanceGetTearOff (Object)");
+  dyn.{core::Object::toString}{() → core::String};
+  nullableClass1.{core::Object::toString}{() → core::String};
+  core::print("DynamicGet (Never)");
+  let final Never #t7 = (let final Never #t8 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.field in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  let final Never #t9 = (let final Never #t10 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.hashCode in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.");
+  core::print("FunctionTearOff");
+  nonNullableFunction.call;
+  let final core::Function? #t11 = nullableFunction in #t11 == null ?{core::Function?} null : #t11{core::Function}.call;
+  nonNullableFunctionType.call;
+  let final () →? core::int #t12 = nullableFunctionType in #t12 == null ?{() →? core::int} null : #t12{() → core::int}.call;
+  nonNullableTypeVariable1.call;
+  let final self::test::T1? #t13 = nullableTypeVariable1 in #t13 == null ?{self::test::T1?} null : #t13{self::test::T1}.call;
+  nonNullableTypeVariable2.call;
+  let final self::test::T2? #t14 = nullableTypeVariable2 in #t14 == null ?{self::test::T2?} null : #t14{self::test::T2}.call;
+  const dynamic function_tearOff = invalid-expression "pkg/front_end/testcases/none/property_get.dart:106:36: Error: Not a constant expression.
+  const dynamic function_tearOff = nonNullableFunction.call;
+                                   ^^^^^^^^^^^^^^^^^^^";
+  core::print(invalid-expression "pkg/front_end/testcases/none/property_get.dart:106:36: Error: Not a constant expression.
+  const dynamic function_tearOff = nonNullableFunction.call;
+                                   ^^^^^^^^^^^^^^^^^^^");
+  core::print("DynamicGet (Invalid)");
+  invalid-expression "pkg/front_end/testcases/none/property_get.dart:110:27: Error: Too few positional arguments: 1 required, 0 given.
+  nonNullableClass1.method().field;
+                          ^" in nonNullableClass1.{self::Class1::method}{<inapplicable>}.(){() → invalid-type}{<invalid>}.field;
+  core::print("DynamicGet (Unresolved)");
+  invalid-expression "pkg/front_end/testcases/none/property_get.dart:113:21: Error: The getter 'unresolved' isn't defined for the class 'Class1'.
+ - 'Class1' is from 'pkg/front_end/testcases/none/property_get.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'unresolved'.
+  nonNullableClass1.unresolved;
+                    ^^^^^^^^^^" in nonNullableClass1{<unresolved>}.unresolved;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = "foo"
+  #C2 = 3
+  #C3 = static-tearoff self::Class1::staticMethod
+  #C4 = static-tearoff self::topLevelMethod
+}
diff --git a/pkg/front_end/testcases/none/property_set.dart.weak.modular.expect b/pkg/front_end/testcases/none/property_set.dart.weak.modular.expect
new file mode 100644
index 0000000..b7f6716
--- /dev/null
+++ b/pkg/front_end/testcases/none/property_set.dart.weak.modular.expect
@@ -0,0 +1,68 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/none/property_set.dart:18:34: Error: Not a constant expression.
+//   const int set_instance_field = nonNullableClass1.field = 42;
+//                                  ^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/none/property_set.dart:18:58: Error: Not a constant expression.
+//   const int set_instance_field = nonNullableClass1.field = 42;
+//                                                          ^
+//
+// pkg/front_end/testcases/none/property_set.dart:23:33: Error: Not a constant expression.
+//   const int set_dynamic_field = dyn.field = 42;
+//                                 ^^^
+//
+// pkg/front_end/testcases/none/property_set.dart:23:43: Error: Not a constant expression.
+//   const int set_dynamic_field = dyn.field = 42;
+//                                           ^
+//
+// pkg/front_end/testcases/none/property_set.dart:29:27: Error: Too few positional arguments: 1 required, 0 given.
+//   nonNullableClass1.method().field = 42;
+//                           ^
+//
+// pkg/front_end/testcases/none/property_set.dart:32:21: Error: The setter 'unresolved' isn't defined for the class 'Class1'.
+//  - 'Class1' is from 'pkg/front_end/testcases/none/property_set.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'unresolved'.
+//   nonNullableClass1.unresolved = 42;
+//                     ^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class1 extends core::Object {
+  field core::int field;
+  constructor •(core::int field) → self::Class1
+    : self::Class1::field = field, super core::Object::•()
+    ;
+  method method(dynamic o) → dynamic {}
+}
+static method test(self::Class1 nonNullableClass1, self::Class1? nullableClass1, dynamic dyn, Never never) → dynamic {
+  core::print("InstanceSet");
+  nonNullableClass1.{self::Class1::field} = 42;
+  let final self::Class1? #t1 = nullableClass1 in #t1 == null ?{core::int?} null : #t1{self::Class1}.{self::Class1::field} = 42;
+  const core::int set_instance_field = invalid-expression "pkg/front_end/testcases/none/property_set.dart:18:58: Error: Not a constant expression.
+  const int set_instance_field = nonNullableClass1.field = 42;
+                                                         ^";
+  core::print("DynamicSet");
+  dyn{dynamic}.field = 42;
+  let final dynamic #t2 = dyn in #t2 == null ?{core::int?} null : #t2{dynamic}.field = 42;
+  const core::int set_dynamic_field = invalid-expression "pkg/front_end/testcases/none/property_set.dart:23:43: Error: Not a constant expression.
+  const int set_dynamic_field = dyn.field = 42;
+                                          ^";
+  core::print("DynamicSet (Never)");
+  (let final Never #t3 = never in throw new _in::ReachabilityError::•("`null` encountered as the result from expression with type `Never`.")){Never}.field = 42;
+  core::print("DynamicSet (Invalid)");
+  invalid-expression "pkg/front_end/testcases/none/property_set.dart:29:27: Error: Too few positional arguments: 1 required, 0 given.
+  nonNullableClass1.method().field = 42;
+                          ^" in nonNullableClass1.{self::Class1::method}{<inapplicable>}.(){() → invalid-type}{<invalid>}.field = 42;
+  core::print("DynamicSet (Unresolved)");
+  invalid-expression "pkg/front_end/testcases/none/property_set.dart:32:21: Error: The setter 'unresolved' isn't defined for the class 'Class1'.
+ - 'Class1' is from 'pkg/front_end/testcases/none/property_set.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'unresolved'.
+  nonNullableClass1.unresolved = 42;
+                    ^^^^^^^^^^" in nonNullableClass1{<unresolved>}.unresolved = 42;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/none/tearoff_opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/none/tearoff_opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..3be713b
--- /dev/null
+++ b/pkg/front_end/testcases/none/tearoff_opt_out.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  method call() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test(self::Class* c) → dynamic {
+  core::Function* f = let final self::Class* #t1 = c in #t1 == null ?{() →* void} null : #t1.{self::Class::call}{() →* void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart.weak.modular.expect
new file mode 100644
index 0000000..ebbaed4
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart.weak.modular.expect
@@ -0,0 +1,218 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:20:17: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// bar3a<X extends B<A<int>>>() => throw 42;
+//                 ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:21:19: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// bar3b<X extends A<B<A<int>>>>() => throw 42;
+//                   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:23:22: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// class Bar1<X extends B<A<int>>> {
+//                      ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:26:22: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   barBar13<X extends B<A<int>>>() => throw 42;
+//                      ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:29:24: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// class Bar2<X extends A<B<A<int>>>> {
+//                        ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:32:24: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   barBar23<X extends A<B<A<int>>>>() => throw 42;
+//                        ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:14:1: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// B<A<int>> bar1a() => throw 42;
+// ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:15:3: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// A<B<A<int>>> bar1b() => throw 42;
+//   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:17:7: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// bar2a(B<A<int>> x) => throw 42;
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:18:9: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// bar2b(A<B<A<int>>> x) => throw 42;
+//         ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:24:3: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   B<A<int>> barBar11() => throw 42;
+//   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:25:12: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   barBar12(B<A<int>> x) => throw 42;
+//            ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:30:5: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   A<B<A<int>>> barBar21() => throw 42;
+//     ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:31:14: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   barBar22(A<B<A<int>>> x) => throw 42;
+//              ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:35:16: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// typedef Baz1 = B<A<int>>;
+//                ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:36:18: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+// typedef Baz2 = A<B<A<int>>>;
+//                  ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:10:3: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   B<A<int>> x1;
+//   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:11:5: Error: Type argument 'A<int>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   A<B<A<int>>> x2;
+//     ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef B<X extends self::A<X> = self::A<dynamic>> = self::A<X>;
+typedef Baz1 = self::A<self::A<core::int>>;
+typedef Baz2 = self::A<self::A<self::A<core::int>>>;
+class A<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+}
+class Bar1<X extends self::A<self::A<core::int>>> extends core::Object {
+  synthetic constructor •() → self::Bar1<self::Bar1::X>
+    : super core::Object::•()
+    ;
+  method barBar11() → self::A<self::A<core::int>>
+    return throw 42;
+  method barBar12(self::A<self::A<core::int>> x) → dynamic
+    return throw 42;
+  method barBar13<X extends self::A<self::A<core::int>>>() → dynamic
+    return throw 42;
+}
+class Bar2<X extends self::A<self::A<self::A<core::int>>>> extends core::Object {
+  synthetic constructor •() → self::Bar2<self::Bar2::X>
+    : super core::Object::•()
+    ;
+  method barBar21() → self::A<self::A<self::A<core::int>>>
+    return throw 42;
+  method barBar22(self::A<self::A<self::A<core::int>>> x) → dynamic
+    return throw 42;
+  method barBar23<X extends self::A<self::A<self::A<core::int>>>>() → dynamic
+    return throw 42;
+}
+static method foo() → dynamic {
+  self::A<self::A<core::int>> x1;
+  self::A<self::A<self::A<core::int>>> x2;
+}
+static method bar1a() → self::A<self::A<core::int>>
+  return throw 42;
+static method bar1b() → self::A<self::A<self::A<core::int>>>
+  return throw 42;
+static method bar2a(self::A<self::A<core::int>> x) → dynamic
+  return throw 42;
+static method bar2b(self::A<self::A<self::A<core::int>>> x) → dynamic
+  return throw 42;
+static method bar3a<X extends self::A<self::A<core::int>>>() → dynamic
+  return throw 42;
+static method bar3b<X extends self::A<self::A<self::A<core::int>>>>() → dynamic
+  return throw 42;
+static method main() → dynamic {}
+static method _#B#new#tearOff<X extends self::A<self::_#B#new#tearOff::X> = self::A<dynamic>>() → self::A<self::_#B#new#tearOff::X>
+  return new self::A::•<self::_#B#new#tearOff::X>();
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks_in_typedef.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks_in_typedef.dart.weak.modular.expect
new file mode 100644
index 0000000..94e4635
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks_in_typedef.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks_in_typedef.dart:10:28: Error: Type argument 'String' doesn't conform to the bound 'int' of the type variable 'X' on 'C'.
+// Try changing type arguments so that they conform to the bounds.
+// typedef B<X extends int> = C<String>;
+//                            ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks_in_typedef.dart:11:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef C<X extends int> = X;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks_in_typedef.dart:9:28: Error: Type argument 'String' doesn't conform to the bound 'int' of the type variable 'X' on 'B'.
+// Try changing type arguments so that they conform to the bounds.
+// typedef A<X extends int> = B<String>;
+//                            ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks_in_typedef.dart:10:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends int> = C<String>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks_in_typedef.dart:6:3: Error: Type argument 'String' doesn't conform to the bound 'int' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+//   A<String> a;
+//   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks_in_typedef.dart:9:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef A<X extends int> = B<String>;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef A<unrelated X extends core::int> = core::String;
+typedef B<unrelated X extends core::int> = core::String;
+typedef C<X extends core::int> = X;
+static method foo() → dynamic {
+  core::String a;
+}
+static method main() → dynamic {}
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/string_patch.dart */ _#A#fromCharCodes#tearOff<unrelated X extends core::int>(core::Iterable<core::int> charCodes, [core::int start = #C1, core::int? end = #C2]) → core::String
+  return core::String::fromCharCodes(charCodes, start, end);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/string_patch.dart */ _#A#fromCharCode#tearOff<unrelated X extends core::int>(core::int charCode) → core::String
+  return core::String::fromCharCode(charCode);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/string_patch.dart */ _#A#fromEnvironment#tearOff<unrelated X extends core::int>(core::String name, {core::String defaultValue = #C3}) → core::String
+  return core::String::fromEnvironment(name, defaultValue: defaultValue);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/string_patch.dart */ _#B#fromCharCodes#tearOff<unrelated X extends core::int>(core::Iterable<core::int> charCodes, [core::int start = #C1, core::int? end = #C2]) → core::String
+  return core::String::fromCharCodes(charCodes, start, end);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/string_patch.dart */ _#B#fromCharCode#tearOff<unrelated X extends core::int>(core::int charCode) → core::String
+  return core::String::fromCharCode(charCode);
+static method /* from org-dartlang-sdk:///sdk/lib/_internal/vm/lib/string_patch.dart */ _#B#fromEnvironment#tearOff<unrelated X extends core::int>(core::String name, {core::String defaultValue = #C3}) → core::String
+  return core::String::fromEnvironment(name, defaultValue: defaultValue);
+
+constants  {
+  #C1 = 0
+  #C2 = null
+  #C3 = ""
+}
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks_no_bodies_main.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks_no_bodies_main.dart.weak.modular.expect
new file mode 100644
index 0000000..cf0d7b6
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks_no_bodies_main.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+
+import "org-dartlang-testcase:///aliased_checks_no_bodies_lib.dart";
+
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks_no_bodies_lib.dart:9:19: Error: Type argument 'int' doesn't conform to the bound 'String' of the type variable 'X' on 'B'.
+// Try changing type arguments so that they conform to the bounds.
+// class C<Y extends B<int>> {}
+//                   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/aliased_checks_no_bodies_lib.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends String> = A;
+//           ^
+//
+import self as self2;
+import "dart:core" as core;
+
+typedef B<unrelated X extends core::String> = self2::A;
+class A extends core::Object {
+  synthetic constructor •() → self2::A
+    : super core::Object::•()
+    ;
+}
+class C<Y extends self2::A> extends core::Object {
+  synthetic constructor •() → self2::C<self2::C::Y>
+    : super core::Object::•()
+    ;
+}
+static method _#B#new#tearOff<unrelated X extends core::String>() → self2::A
+  return new self2::A::•();
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/issue41501.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/issue41501.dart.weak.modular.expect
new file mode 100644
index 0000000..1527b5e
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/issue41501.dart.weak.modular.expect
@@ -0,0 +1,66 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue41501.dart:13:42: Error: The value 'null' can't be assigned to a variable of type 'FutureOr<A Function()>' because 'FutureOr<A Function()>' is not nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue41501_lib.dart'.
+//   FutureOr<AAlias> foLegacyNonNullable = null; // error
+//                                          ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue41501.dart:15:47: Error: The value 'null' can't be assigned to a variable of type 'FutureOr<A>' because 'FutureOr<A>' is not nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue41501_lib.dart'.
+//   FutureOr<AAliasNonNullable> foNonNullable = null; // error
+//                                               ^
+//
+import self as self;
+import "issue41501_lib.dart" as opt;
+
+import "dart:async";
+import "org-dartlang-testcase:///issue41501_lib.dart";
+
+typedef AAliasNonNullable = opt::A;
+typedef AAliasNullable = opt::A?;
+static method test() → dynamic {
+  FutureOr<() → opt::A*>foLegacyNonNullable = invalid-expression "pkg/front_end/testcases/nonfunction_type_aliases/issue41501.dart:13:42: Error: The value 'null' can't be assigned to a variable of type 'FutureOr<A Function()>' because 'FutureOr<A Function()>' is not nullable.
+ - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue41501_lib.dart'.
+  FutureOr<AAlias> foLegacyNonNullable = null; // error
+                                         ^" in null as{TypeError,ForNonNullableByDefault} FutureOr<() → opt::A*>;
+  FutureOr<() →? opt::A*>foLegacyNullable = null;
+  FutureOr<opt::A>foNonNullable = invalid-expression "pkg/front_end/testcases/nonfunction_type_aliases/issue41501.dart:15:47: Error: The value 'null' can't be assigned to a variable of type 'FutureOr<A>' because 'FutureOr<A>' is not nullable.
+ - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue41501_lib.dart'.
+  FutureOr<AAliasNonNullable> foNonNullable = null; // error
+                                              ^" in null as{TypeError,ForNonNullableByDefault} FutureOr<opt::A>;
+  FutureOr<opt::A?>foNullable = null;
+  FutureOr<opt::A?>foNonNullableNullable = null;
+  FutureOr<opt::A?>foNullableNullable = null;
+}
+static method main() → dynamic {}
+
+library opted_out_lib;
+import self as opt;
+import "dart:core" as core;
+
+import "dart:async";
+import "org-dartlang-testcase:///issue41501.dart";
+
+typedef AAlias = () →* opt::A*;
+class A extends core::Object {
+  synthetic constructor •() → opt::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  FutureOr<() →* opt::A*>* foLegacy = null;
+  FutureOr<opt::A*>* foNonNullable = null;
+  FutureOr<opt::A*>* foNullable = null;
+}
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart.weak.modular.expect
new file mode 100644
index 0000000..99ac769
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart.weak.modular.expect
@@ -0,0 +1,75 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart:15:3: Error: Inferred type argument 'A<Object?>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   A(); // Error.
+//   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart:17:3: Error: Inferred type argument 'A2<Object?>' doesn't conform to the bound 'A2<X>' of the type variable 'X' on 'A2'.
+//  - 'A2' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   A2(); // Error.
+//   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart:8:10: Context: This is the type variable whose bound isn't conformed to.
+// class A2<X extends A2<X>> {
+//          ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart:14:3: Error: Inferred type argument 'A<Object?>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'B'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   B(); // Error.
+//   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart:6:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart:16:3: Error: Inferred type argument 'A2<Object?>' doesn't conform to the bound 'A2<X>' of the type variable 'X' on 'B2'.
+//  - 'A2' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   B2(); // Error.
+//   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart:11:12: Context: This is the type variable whose bound isn't conformed to.
+// typedef B2<X extends A2<X>> = A2<X>;
+//            ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart:16:3: Error: Inferred type argument 'A2<Object?>' doesn't conform to the bound 'A2<X>' of the type variable 'X' on 'A2'.
+//  - 'A2' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   B2(); // Error.
+//   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue42446.dart:8:10: Context: This is the type variable whose bound isn't conformed to.
+// class A2<X extends A2<X>> {
+//          ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef B<X extends self::A<X> = self::A<dynamic>> = self::A<X>;
+typedef B2<X extends self::A2<X> = self::A2<dynamic>> = self::A2<X>;
+class A<X extends self::A<self::A::X> = self::A<dynamic>> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X>
+    : super core::Object::•()
+    ;
+}
+class A2<X extends self::A2<self::A2::X> = self::A2<dynamic>> extends core::Object {
+  static factory •<X extends self::A2<self::A2::•::X> = self::A2<dynamic>>() → self::A2<self::A2::•::X>
+    return throw 42;
+}
+static method foo() → dynamic {
+  new self::A::•<self::A<core::Object?>>();
+  new self::A::•<self::A<core::Object?>>();
+  self::A2::•<self::A2<core::Object?>>();
+  self::A2::•<self::A2<core::Object?>>();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/issue45051.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/issue45051.dart.weak.modular.expect
new file mode 100644
index 0000000..ae8fcc4
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/issue45051.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef BAlias = self::B;
+class A extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1, #C2]/*isLegacy*/;
+  static factory •() → self::A
+    return new self::B::•();
+  static factory named() → self::A
+    return new self::B::named();
+}
+class B extends core::Object implements self::A {
+  constructor •() → self::B
+    : super core::Object::•()
+    ;
+  constructor named() → self::B
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = constructor-tearoff self::A::•
+  #C2 = constructor-tearoff self::A::named
+}
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart.weak.modular.expect
new file mode 100644
index 0000000..61ac447
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart.weak.modular.expect
@@ -0,0 +1,160 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:32:9: Error: Inferred type argument 'A<Object?>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     new A();
+//         ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:13:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>> {}
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:34:7: Error: Inferred type argument 'Object?' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'call'.
+//  - 'Object' is from 'dart:core'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     f1(() => captureTypeArgument());
+//       ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:35:7: Error: Inferred type argument 'Object?' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'call'.
+//  - 'Object' is from 'dart:core'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     f2(() => captureTypeArgument());
+//       ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:36:11: Error: Inferred type argument 'Object?' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'local1'.
+//  - 'Object' is from 'dart:core'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     local1(() => captureTypeArgument());
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:37:11: Error: Inferred type argument 'Object?' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'local2'.
+//  - 'Object' is from 'dart:core'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     local2(() => captureTypeArgument());
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:38:5: Error: Inferred type argument 'Object?' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'topLevel1'.
+//  - 'Object' is from 'dart:core'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     topLevel1(() => captureTypeArgument());
+//     ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:16:16: Context: This is the type variable whose bound isn't conformed to.
+// void topLevel1<X extends A<X>>(A<X> Function() g) => g();
+//                ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:39:5: Error: Inferred type argument 'Object?' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'topLevel2'.
+//  - 'Object' is from 'dart:core'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     topLevel2(() => captureTypeArgument());
+//     ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:18:16: Context: This is the type variable whose bound isn't conformed to.
+// void topLevel2<X extends C<X>>(C<X> Function() g) => g();
+//                ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:40:5: Error: Inferred type argument 'Object?' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'Class.instance1'.
+//  - 'Object' is from 'dart:core'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+//  - 'Class' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     instance1(() => captureTypeArgument());
+//     ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:41:5: Error: Inferred type argument 'Object?' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'Class.instance2'.
+//  - 'Object' is from 'dart:core'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+//  - 'Class' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     instance2(() => captureTypeArgument());
+//     ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:33:9: Error: Inferred type argument 'A<Object?>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'C'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     new C();
+//         ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:14:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef C<X extends A<X>> = A<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:47:11: Error: Inferred type argument 'Object?' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'Subclass.instance1'.
+//  - 'Object' is from 'dart:core'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+//  - 'Subclass' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     super.instance1(() => captureTypeArgument());
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart:48:11: Error: Inferred type argument 'Object?' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'Subclass.instance2'.
+//  - 'Object' is from 'dart:core'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+//  - 'Subclass' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45464.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//     super.instance2(() => captureTypeArgument());
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef C<X extends self::A<X> = self::A<dynamic>> = self::A<X>;
+class A<X extends self::A<self::A::X> = self::A<dynamic>> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X>
+    : super core::Object::•()
+    ;
+}
+class Class extends core::Object {
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  method instance1<X extends self::A<self::Class::instance1::X> = self::A<dynamic>>(() → self::A<self::Class::instance1::X> g) → void
+    return g(){() → self::A<self::Class::instance1::X>};
+  method instance2<X extends self::A<self::Class::instance2::X> = self::A<dynamic>>(() → self::A<self::Class::instance2::X> g) → void
+    return g(){() → self::A<self::Class::instance2::X>};
+  method test() → void {
+    function local1<X extends self::A<X> = self::A<dynamic>>(() → self::A<X> g) → void
+      return g(){() → self::A<X>};
+    function local2<X extends self::A<X> = self::A<dynamic>>(() → self::A<X> g) → void
+      return g(){() → self::A<X>};
+    <X extends self::A<X> = self::A<dynamic>>(() → self::A<X>) → void f1 = local1;
+    <X extends self::A<X> = self::A<dynamic>>(() → self::A<X>) → void f2 = local2;
+    new self::A::•<self::A<core::Object?>>();
+    new self::A::•<self::A<core::Object?>>();
+    f1<core::Object?>(() → self::A<core::Object?> => self::captureTypeArgument<self::A<core::Object?>>()){(() → self::A<core::Object?>) → void};
+    f2<core::Object?>(() → self::A<core::Object?> => self::captureTypeArgument<self::A<core::Object?>>()){(() → self::A<core::Object?>) → void};
+    local1<core::Object?>(() → self::A<core::Object?> => self::captureTypeArgument<self::A<core::Object?>>()){(() → self::A<core::Object?>) → void};
+    local2<core::Object?>(() → self::A<core::Object?> => self::captureTypeArgument<self::A<core::Object?>>()){(() → self::A<core::Object?>) → void};
+    self::topLevel1<core::Object?>(() → self::A<core::Object?> => self::captureTypeArgument<self::A<core::Object?>>());
+    self::topLevel2<core::Object?>(() → self::A<core::Object?> => self::captureTypeArgument<self::A<core::Object?>>());
+    this.{self::Class::instance1}<core::Object?>(() → self::A<core::Object?> => self::captureTypeArgument<self::A<core::Object?>>()){(() → self::A<core::Object?>) → void};
+    this.{self::Class::instance2}<core::Object?>(() → self::A<core::Object?> => self::captureTypeArgument<self::A<core::Object?>>()){(() → self::A<core::Object?>) → void};
+  }
+}
+class Subclass extends self::Class {
+  synthetic constructor •() → self::Subclass
+    : super self::Class::•()
+    ;
+  method test() → void {
+    super.{self::Class::instance1}<core::Object?>(() → self::A<core::Object?> => self::captureTypeArgument<self::A<core::Object?>>());
+    super.{self::Class::instance2}<core::Object?>(() → self::A<core::Object?> => self::captureTypeArgument<self::A<core::Object?>>());
+  }
+}
+static field core::Type? _capturedTypeArgument;
+static method captureTypeArgument<X extends core::Object? = dynamic>() → self::captureTypeArgument::X% {
+  self::_capturedTypeArgument = self::captureTypeArgument::X%;
+  core::print("X: ${self::captureTypeArgument::X%}");
+  throw "Error";
+}
+static method topLevel1<X extends self::A<self::topLevel1::X> = self::A<dynamic>>(() → self::A<self::topLevel1::X> g) → void
+  return g(){() → self::A<self::topLevel1::X>};
+static method topLevel2<X extends self::A<self::topLevel2::X> = self::A<dynamic>>(() → self::A<self::topLevel2::X> g) → void
+  return g(){() → self::A<self::topLevel2::X>};
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/issue45491.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/issue45491.dart.weak.modular.expect
new file mode 100644
index 0000000..ada86f5
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/issue45491.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45491.dart:7:21: Error: Inferred type argument 'A<dynamic>' doesn't conform to the bound 'A<X>' of the type variable 'X' on 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45491.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+// typedef AAlias<X> = A;
+//                     ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45491.dart:5:9: Context: This is the type variable whose bound isn't conformed to.
+// class A<X extends A<X>> {}
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef AAlias<unrelated X extends core::Object? = dynamic> = self::A<self::A<dynamic>>;
+class A<X extends self::A<self::A::X> = self::A<dynamic>> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X>
+    : super core::Object::•()
+    ;
+}
+static method main() → void {}
+static method _#AAlias#new#tearOff<unrelated X extends core::Object? = dynamic>() → self::A<self::A<dynamic>>
+  return new self::A::•<self::A<dynamic>>();
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/issue45519.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/issue45519.dart.weak.modular.expect
new file mode 100644
index 0000000..0d5fcd0
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/issue45519.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45519.dart:10:3: Error: Inferred type argument 'C<dynamic> Function(C<dynamic>)' doesn't conform to the bound 'C<X> Function(C<X>)' of the type variable 'X' on 'A'.
+//  - 'C' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45519.dart'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   A a = throw 42; // Error.
+//   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45519.dart:7:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef A<X extends G<C<X>>> = C<X>;
+//           ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45519.dart:10:3: Context: If you want 'A<C<dynamic> Function(C<dynamic>)>' to be a super-bounded type, note that the inverted type 'A<G<C<Never>>>' must then satisfy its bounds, which it does not.
+//  - 'C' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45519.dart'.
+//   A a = throw 42; // Error.
+//   ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef G<invariant X extends core::Object? = dynamic> = (X%) → X%;
+typedef A<X extends (self::C<X>) → self::C<X> = (self::C<dynamic>) → self::C<dynamic>> = self::C<X>;
+class C<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::X%>
+    : super core::Object::•()
+    ;
+}
+static method test() → dynamic {
+  self::C<(self::C<dynamic>) → self::C<dynamic>> a = throw 42;
+}
+static method main() → dynamic {}
+static method _#A#new#tearOff<X extends (self::C<self::_#A#new#tearOff::X>) → self::C<self::_#A#new#tearOff::X> = (self::C<dynamic>) → self::C<dynamic>>() → self::C<self::_#A#new#tearOff::X>
+  return new self::C::•<self::_#A#new#tearOff::X>();
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart.weak.modular.expect
new file mode 100644
index 0000000..14a187b
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart.weak.modular.expect
@@ -0,0 +1,115 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart:21:5: Error: Inferred type argument 'C<Object?> Function(C<Never>)' doesn't conform to the bound 'C<X> Function(C<X>)' of the type variable 'X' on 'A'.
+//  - 'C' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   A.foo(); // Error.
+//     ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart:16:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef A<X extends G<C<X>>> = C<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart:23:3: Error: Inferred type argument 'D<Object?> Function(D<Never>)' doesn't conform to the bound 'D<X> Function(D<X>)' of the type variable 'X' on 'B'.
+//  - 'D' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   B(); // Error.
+//   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart:17:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends G<D<X>>> = D<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart:20:3: Error: Inferred type argument 'C<Object?> Function(C<Never>)' doesn't conform to the bound 'C<X> Function(C<X>)' of the type variable 'X' on 'A'.
+//  - 'C' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   A(); // Error.
+//   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart:16:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef A<X extends G<C<X>>> = C<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart:22:5: Error: Inferred type argument 'C<Object?> Function(C<Never>)' doesn't conform to the bound 'C<X> Function(C<X>)' of the type variable 'X' on 'A'.
+//  - 'C' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   A.bar(); // Error.
+//     ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart:16:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef A<X extends G<C<X>>> = C<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart:24:5: Error: Inferred type argument 'D<Object?> Function(D<Never>)' doesn't conform to the bound 'D<X> Function(D<X>)' of the type variable 'X' on 'B'.
+//  - 'D' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   B.foo(); // Error.
+//     ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart:17:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends G<D<X>>> = D<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart:25:5: Error: Inferred type argument 'D<Object?> Function(D<Never>)' doesn't conform to the bound 'D<X> Function(D<X>)' of the type variable 'X' on 'B'.
+//  - 'D' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   B.bar(); // Error.
+//     ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45519_2.dart:17:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef B<X extends G<D<X>>> = D<X>;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef G<invariant X extends core::Object? = dynamic> = (X%) → X%;
+typedef A<X extends (self::C<X>) → self::C<X> = (self::C<dynamic>) → self::C<dynamic>> = self::C<X>;
+typedef B<X extends (self::D<X>) → self::D<X> = (self::D<dynamic>) → self::D<dynamic>> = self::D<X>;
+class C<X extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1]/*isLegacy*/;
+  constructor foo() → self::C<self::C::X%>
+    : super core::Object::•() {}
+  static factory •<X extends core::Object? = dynamic>() → self::C<self::C::•::X%>
+    return new self::C::foo<self::C::•::X%>();
+  static factory bar<X extends core::Object? = dynamic>() → self::C<self::C::bar::X%>
+    return self::C::•<self::C::bar::X%>();
+}
+class D<X extends core::Object? = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C2]/*isLegacy*/;
+  constructor •() → self::D<self::D::X%>
+    : super core::Object::•()
+    ;
+  static factory foo<X extends core::Object? = dynamic>() → self::D<self::D::foo::X%>
+    return new self::D::•<self::D::foo::X%>();
+  static factory bar<X extends core::Object? = dynamic>() → self::D<self::D::bar::X%>
+    return new self::D::•<self::D::bar::X%>();
+}
+static method test() → dynamic {
+  self::C::•<(self::C<Never>) → self::C<core::Object?>>();
+  new self::C::foo<(self::C<Never>) → self::C<core::Object?>>();
+  self::C::•<(self::C<Never>) → self::C<core::Object?>>();
+  new self::D::•<(self::D<Never>) → self::D<core::Object?>>();
+  self::D::foo<(self::D<Never>) → self::D<core::Object?>>();
+  new self::D::•<(self::D<Never>) → self::D<core::Object?>>();
+}
+static method main() → dynamic {}
+static method _#A#new#tearOff<X extends (self::C<self::_#A#new#tearOff::X>) → self::C<self::_#A#new#tearOff::X> = (self::C<dynamic>) → self::C<dynamic>>() → self::C<self::_#A#new#tearOff::X>
+  return self::C::•<self::_#A#new#tearOff::X>();
+static method _#A#foo#tearOff<X extends (self::C<self::_#A#foo#tearOff::X>) → self::C<self::_#A#foo#tearOff::X> = (self::C<dynamic>) → self::C<dynamic>>() → self::C<self::_#A#foo#tearOff::X>
+  return new self::C::foo<self::_#A#foo#tearOff::X>();
+static method _#A#bar#tearOff<X extends (self::C<self::_#A#bar#tearOff::X>) → self::C<self::_#A#bar#tearOff::X> = (self::C<dynamic>) → self::C<dynamic>>() → self::C<self::_#A#bar#tearOff::X>
+  return self::C::bar<self::_#A#bar#tearOff::X>();
+static method _#B#new#tearOff<X extends (self::D<self::_#B#new#tearOff::X>) → self::D<self::_#B#new#tearOff::X> = (self::D<dynamic>) → self::D<dynamic>>() → self::D<self::_#B#new#tearOff::X>
+  return new self::D::•<self::_#B#new#tearOff::X>();
+static method _#B#foo#tearOff<X extends (self::D<self::_#B#foo#tearOff::X>) → self::D<self::_#B#foo#tearOff::X> = (self::D<dynamic>) → self::D<dynamic>>() → self::D<self::_#B#foo#tearOff::X>
+  return self::D::foo<self::_#B#foo#tearOff::X>();
+static method _#B#bar#tearOff<X extends (self::D<self::_#B#bar#tearOff::X>) → self::D<self::_#B#bar#tearOff::X> = (self::D<dynamic>) → self::D<dynamic>>() → self::D<self::_#B#bar#tearOff::X>
+  return self::D::bar<self::_#B#bar#tearOff::X>();
+
+constants  {
+  #C1 = constructor-tearoff self::C::bar
+  #C2 = constructor-tearoff self::D::bar
+}
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/issue45626.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/issue45626.dart.weak.modular.expect
new file mode 100644
index 0000000..84c660a
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/issue45626.dart.weak.modular.expect
@@ -0,0 +1,126 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45626.dart:10:23: Error: 'C' can only be implemented once.
+// Try removing 1 of the occurrences.
+// class D implements C, C {}
+//                       ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45626.dart:11:24: Error: 'C' can only be implemented once.
+// Try removing 1 of the occurrences.
+// class D2 implements C, CAlias {}
+//                        ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45626.dart:12:29: Error: 'C' can only be implemented once.
+// Try removing 1 of the occurrences.
+// class D3 implements CAlias, C {}
+//                             ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45626.dart:13:24: Error: 'C' can only be implemented once.
+// Try removing 1 of the occurrences.
+// class D4 implements C, self.C {}
+//                        ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45626.dart:14:29: Error: 'C' can only be implemented once.
+// Try removing 1 of the occurrences.
+// class D5 implements self.C, C {}
+//                             ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45626.dart:16:16: Error: 'C' can only be implemented once.
+// Try removing 1 of the occurrences.
+// mixin CM on C, C {}
+//                ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45626.dart:17:17: Error: 'C' can only be implemented once.
+// Try removing 1 of the occurrences.
+// mixin CM2 on C, CAlias {}
+//                 ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45626.dart:18:22: Error: 'C' can only be implemented once.
+// Try removing 1 of the occurrences.
+// mixin CM3 on CAlias, C {}
+//                      ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45626.dart:19:22: Error: 'C' can only be implemented once.
+// Try removing 1 of the occurrences.
+// mixin CM4 on self.C, C {}
+//                      ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45626.dart:20:17: Error: 'C' can only be implemented once.
+// Try removing 1 of the occurrences.
+// mixin CM5 on C, self.C {}
+//                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue45626.dart" as self;
+
+typedef CAlias = self::C;
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+class D extends core::Object implements self::C, self::C {
+  synthetic constructor •() → self::D
+    : super core::Object::•()
+    ;
+}
+class D2 extends core::Object implements self::C, self::C {
+  synthetic constructor •() → self::D2
+    : super core::Object::•()
+    ;
+}
+class D3 extends core::Object implements self::C, self::C {
+  synthetic constructor •() → self::D3
+    : super core::Object::•()
+    ;
+}
+class D4 extends core::Object implements self::C, self::C {
+  synthetic constructor •() → self::D4
+    : super core::Object::•()
+    ;
+}
+class D5 extends core::Object implements self::C, self::C {
+  synthetic constructor •() → self::D5
+    : super core::Object::•()
+    ;
+}
+abstract class _CM&C&C extends core::Object implements self::C, self::C /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_CM&C&C
+    : super core::Object::•()
+    ;
+}
+abstract class CM extends self::_CM&C&C /*isMixinDeclaration*/  {
+}
+abstract class _CM2&C&CAlias extends core::Object implements self::C, self::C /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_CM2&C&CAlias
+    : super core::Object::•()
+    ;
+}
+abstract class CM2 extends self::_CM2&C&CAlias /*isMixinDeclaration*/  {
+}
+abstract class _CM3&CAlias&C extends core::Object implements self::C, self::C /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_CM3&CAlias&C
+    : super core::Object::•()
+    ;
+}
+abstract class CM3 extends self::_CM3&CAlias&C /*isMixinDeclaration*/  {
+}
+abstract class _CM4&C&C extends core::Object implements self::C, self::C /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_CM4&C&C
+    : super core::Object::•()
+    ;
+}
+abstract class CM4 extends self::_CM4&C&C /*isMixinDeclaration*/  {
+}
+abstract class _CM5&C&C extends core::Object implements self::C, self::C /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_CM5&C&C
+    : super core::Object::•()
+    ;
+}
+abstract class CM5 extends self::_CM5&C&C /*isMixinDeclaration*/  {
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/issue45658.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/issue45658.dart.weak.modular.expect
new file mode 100644
index 0000000..0ed8715
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/issue45658.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45658.dart:13:3: Error: Inferred type argument 'C<Object?>' doesn't conform to the bound 'C<X>' of the type variable 'X' on 'A'.
+//  - 'C' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45658.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   A();
+//   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45658.dart:10:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef A<X extends C<X>> = C<X>;
+//           ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45658.dart:14:5: Error: Inferred type argument 'C<Object?>' doesn't conform to the bound 'C<X>' of the type variable 'X' on 'A'.
+//  - 'C' is from 'pkg/front_end/testcases/nonfunction_type_aliases/issue45658.dart'.
+//  - 'Object' is from 'dart:core'.
+// Try specifying type arguments explicitly so that they conform to the bounds.
+//   A.foo();
+//     ^
+// pkg/front_end/testcases/nonfunction_type_aliases/issue45658.dart:10:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef A<X extends C<X>> = C<X>;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef A<X extends self::C<X> = self::C<dynamic>> = self::C<X>;
+class C<X extends core::Object? = dynamic> extends core::Object {
+  constructor •() → self::C<self::C::X%>
+    : super core::Object::•()
+    ;
+  static factory foo<X extends core::Object? = dynamic>() → self::C<self::C::foo::X%>
+    return new self::C::•<self::C::foo::X%>();
+}
+static method foo() → dynamic {
+  new self::C::•<self::C<core::Object?>>();
+  self::C::foo<self::C<core::Object?>>();
+}
+static method main() → dynamic {}
+static method _#A#new#tearOff<X extends self::C<self::_#A#new#tearOff::X> = self::C<dynamic>>() → self::C<self::_#A#new#tearOff::X>
+  return new self::C::•<self::_#A#new#tearOff::X>();
+static method _#A#foo#tearOff<X extends self::C<self::_#A#foo#tearOff::X> = self::C<dynamic>>() → self::C<self::_#A#foo#tearOff::X>
+  return self::C::foo<self::_#A#foo#tearOff::X>();
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/issue_43084/issue_43084.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/issue_43084/issue_43084.dart.weak.modular.expect
new file mode 100644
index 0000000..da53398
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/issue_43084/issue_43084.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library;
+import self as self;
+import "issue_43084_lib.dart" as iss;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue_43084_lib.dart";
+
+static method main() → dynamic {
+  iss::Foo<core::int*>* x = new iss::Foo::•<core::int*>();
+  core::print(x);
+}
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart.weak.modular.expect
new file mode 100644
index 0000000..6095355
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart.weak.modular.expect
@@ -0,0 +1,383 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:32:18: Error: Can't use a typedef denoting a type variable as a constructor, nor for a static member access.
+// class D1 extends TAlias<A> {}
+//                  ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:16: Context: This is the type variable ultimately denoted.
+// typedef TAlias<T> = T?;
+//                ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:34:19: Error: Can't use a typedef denoting a type variable as a constructor, nor for a static member access.
+// class D1a extends prefix.TAlias<A> {}
+//                   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:16: Context: This is the type variable ultimately denoted.
+// typedef TAlias<T> = T?;
+//                ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:36:19: Error: Can't use a typedef denoting a type variable as a constructor, nor for a static member access.
+// class D1b extends TAlias<prefix.A> {}
+//                   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:16: Context: This is the type variable ultimately denoted.
+// typedef TAlias<T> = T?;
+//                ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:38:21: Error: Can't use a typedef denoting a type variable as a constructor, nor for a static member access.
+// class D2 implements TAlias<A> {}
+//                     ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:16: Context: This is the type variable ultimately denoted.
+// typedef TAlias<T> = T?;
+//                ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:40:19: Error: Can't use a typedef denoting a type variable as a constructor, nor for a static member access.
+// class D3 = A with TAlias<B>;
+//                   ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:16: Context: This is the type variable ultimately denoted.
+// typedef TAlias<T> = T?;
+//                ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:42:32: Error: Can't use a typedef denoting a type variable as a constructor, nor for a static member access.
+// class D4 = A with B implements TAlias<C>;
+//                                ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:16: Context: This is the type variable ultimately denoted.
+// typedef TAlias<T> = T?;
+//                ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:44:25: Error: Can't use a typedef denoting a type variable as a constructor, nor for a static member access.
+// class D5 extends A with TAlias<B> {}
+//                         ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:16: Context: This is the type variable ultimately denoted.
+// typedef TAlias<T> = T?;
+//                ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:46:13: Error: Can't use a typedef denoting a type variable as a constructor, nor for a static member access.
+// mixin N1 on TAlias<A> {}
+//             ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:16: Context: This is the type variable ultimately denoted.
+// typedef TAlias<T> = T?;
+//                ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:48:14: Error: Can't use a typedef denoting a type variable as a constructor, nor for a static member access.
+// mixin N1a on prefix.TAlias<A> {}
+//              ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:16: Context: This is the type variable ultimately denoted.
+// typedef TAlias<T> = T?;
+//                ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:50:14: Error: Can't use a typedef denoting a type variable as a constructor, nor for a static member access.
+// mixin N1b on TAlias<prefix.A> {}
+//              ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:16: Context: This is the type variable ultimately denoted.
+// typedef TAlias<T> = T?;
+//                ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:52:16: Error: Can't use a typedef denoting a type variable as a constructor, nor for a static member access.
+// mixin N2 on A, TAlias<B> {}
+//                ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:16: Context: This is the type variable ultimately denoted.
+// typedef TAlias<T> = T?;
+//                ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:54:26: Error: Can't use a typedef denoting a type variable as a constructor, nor for a static member access.
+// mixin N3 on A implements TAlias<B> {}
+//                          ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:16: Context: This is the type variable ultimately denoted.
+// typedef TAlias<T> = T?;
+//                ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:40:7: Error: The type 'TAlias' can't be mixed in.
+// class D3 = A with TAlias<B>;
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:9: Context: The issue arises via this type alias.
+// typedef TAlias<T> = T?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:44:7: Error: The type 'TAlias' can't be mixed in.
+// class D5 extends A with TAlias<B> {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:9: Context: The issue arises via this type alias.
+// typedef TAlias<T> = T?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:16:7: Error: The type 'AAlias' which is an alias of 'A?' can't be used as supertype because it is nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// class C1 extends AAlias {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:11:9: Context: The issue arises via this type alias.
+// typedef AAlias = A?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:18:7: Error: The type 'AAlias' which is an alias of 'A?' can't be used as supertype because it is nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// class C2 implements AAlias {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:11:9: Context: The issue arises via this type alias.
+// typedef AAlias = A?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:20:7: Error: The type 'BAlias' which is an alias of 'B?' can't be used as supertype because it is nullable.
+//  - 'B' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// class C3 = A with BAlias;
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:12:9: Context: The issue arises via this type alias.
+// typedef BAlias = B?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:22:7: Error: The type 'CAlias' which is an alias of 'C?' can't be used as supertype because it is nullable.
+//  - 'C' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// class C4 = A with B implements CAlias;
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:13:9: Context: The issue arises via this type alias.
+// typedef CAlias = C?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:24:7: Error: The type 'BAlias' which is an alias of 'B?' can't be used as supertype because it is nullable.
+//  - 'B' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// class C5 extends A with BAlias {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:12:9: Context: The issue arises via this type alias.
+// typedef BAlias = B?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:26:7: Error: The type 'AAlias' which is an alias of 'A?' can't be used as supertype because it is nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// mixin M1 on AAlias {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:11:9: Context: The issue arises via this type alias.
+// typedef AAlias = A?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:28:7: Error: The type 'BAlias' which is an alias of 'B?' can't be used as supertype because it is nullable.
+//  - 'B' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// mixin M2 on A, BAlias {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:12:9: Context: The issue arises via this type alias.
+// typedef BAlias = B?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:30:7: Error: The type 'BAlias' which is an alias of 'B?' can't be used as supertype because it is nullable.
+//  - 'B' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// mixin M3 on A implements BAlias {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:12:9: Context: The issue arises via this type alias.
+// typedef BAlias = B?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:32:7: Error: The type 'TAlias<A>' which is an alias of 'A?' can't be used as supertype because it is nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// class D1 extends TAlias<A> {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:9: Context: The issue arises via this type alias.
+// typedef TAlias<T> = T?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:34:7: Error: The type 'prefix.TAlias<A>' which is an alias of 'A?' can't be used as supertype because it is nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// class D1a extends prefix.TAlias<A> {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:9: Context: The issue arises via this type alias.
+// typedef TAlias<T> = T?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:36:7: Error: The type 'TAlias<prefix.A>' which is an alias of 'A?' can't be used as supertype because it is nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// class D1b extends TAlias<prefix.A> {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:9: Context: The issue arises via this type alias.
+// typedef TAlias<T> = T?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:38:7: Error: The type 'TAlias<A>' which is an alias of 'A?' can't be used as supertype because it is nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// class D2 implements TAlias<A> {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:9: Context: The issue arises via this type alias.
+// typedef TAlias<T> = T?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:40:7: Error: The type 'TAlias<B>' which is an alias of 'B?' can't be used as supertype because it is nullable.
+//  - 'B' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// class D3 = A with TAlias<B>;
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:9: Context: The issue arises via this type alias.
+// typedef TAlias<T> = T?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:42:7: Error: The type 'TAlias<C>' which is an alias of 'C?' can't be used as supertype because it is nullable.
+//  - 'C' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// class D4 = A with B implements TAlias<C>;
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:9: Context: The issue arises via this type alias.
+// typedef TAlias<T> = T?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:44:7: Error: The type 'TAlias<B>' which is an alias of 'B?' can't be used as supertype because it is nullable.
+//  - 'B' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// class D5 extends A with TAlias<B> {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:9: Context: The issue arises via this type alias.
+// typedef TAlias<T> = T?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:46:7: Error: The type 'TAlias<A>' which is an alias of 'A?' can't be used as supertype because it is nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// mixin N1 on TAlias<A> {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:9: Context: The issue arises via this type alias.
+// typedef TAlias<T> = T?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:48:7: Error: The type 'prefix.TAlias<A>' which is an alias of 'A?' can't be used as supertype because it is nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// mixin N1a on prefix.TAlias<A> {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:9: Context: The issue arises via this type alias.
+// typedef TAlias<T> = T?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:50:7: Error: The type 'TAlias<prefix.A>' which is an alias of 'A?' can't be used as supertype because it is nullable.
+//  - 'A' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// mixin N1b on TAlias<prefix.A> {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:9: Context: The issue arises via this type alias.
+// typedef TAlias<T> = T?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:52:7: Error: The type 'TAlias<B>' which is an alias of 'B?' can't be used as supertype because it is nullable.
+//  - 'B' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// mixin N2 on A, TAlias<B> {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:9: Context: The issue arises via this type alias.
+// typedef TAlias<T> = T?;
+//         ^
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:54:7: Error: The type 'TAlias<B>' which is an alias of 'B?' can't be used as supertype because it is nullable.
+//  - 'B' is from 'pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart'.
+// mixin N3 on A implements TAlias<B> {}
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/nullable_supertypes.dart:14:9: Context: The issue arises via this type alias.
+// typedef TAlias<T> = T?;
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///nullable_supertypes.dart" as prefix;
+
+typedef AAlias = self::A?;
+typedef BAlias = self::B?;
+typedef CAlias = self::C?;
+typedef TAlias<T extends core::Object? = dynamic> = T?;
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+class C1 extends core::Object {
+  synthetic constructor •() → self::C1
+    : super core::Object::•()
+    ;
+}
+class C2 extends core::Object {
+  synthetic constructor •() → self::C2
+    : super core::Object::•()
+    ;
+}
+class C3 extends self::A {
+  synthetic constructor •() → self::C3
+    : super self::A::•()
+    ;
+}
+class C4 = self::A with self::B {
+  synthetic constructor •() → self::C4
+    : super self::A::•()
+    ;
+}
+abstract class _C5&A&BAlias extends self::A /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_C5&A&BAlias
+    : super self::A::•()
+    ;
+}
+class C5 extends self::_C5&A&BAlias {
+  synthetic constructor •() → self::C5
+    : super self::_C5&A&BAlias::•()
+    ;
+}
+abstract class M1 extends core::Object /*isMixinDeclaration*/  {
+}
+abstract class _M2&A&BAlias extends core::Object implements self::A /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_M2&A&BAlias
+    : super core::Object::•()
+    ;
+}
+abstract class M2 extends self::_M2&A&BAlias /*isMixinDeclaration*/  {
+}
+abstract class M3 extends self::A /*isMixinDeclaration*/  {
+}
+class D1 extends core::Object {
+  synthetic constructor •() → self::D1
+    : super core::Object::•()
+    ;
+}
+class D1a extends core::Object {
+  synthetic constructor •() → self::D1a
+    : super core::Object::•()
+    ;
+}
+class D1b extends core::Object {
+  synthetic constructor •() → self::D1b
+    : super core::Object::•()
+    ;
+}
+class D2 extends core::Object {
+  synthetic constructor •() → self::D2
+    : super core::Object::•()
+    ;
+}
+class D3 extends self::A {
+  synthetic constructor •() → self::D3
+    : super self::A::•()
+    ;
+}
+class D4 = self::A with self::B {
+  synthetic constructor •() → self::D4
+    : super self::A::•()
+    ;
+}
+abstract class _D5&A&TAlias extends self::A /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_D5&A&TAlias
+    : super self::A::•()
+    ;
+}
+class D5 extends self::_D5&A&TAlias {
+  synthetic constructor •() → self::D5
+    : super self::_D5&A&TAlias::•()
+    ;
+}
+abstract class N1 extends core::Object /*isMixinDeclaration*/  {
+}
+abstract class N1a extends core::Object /*isMixinDeclaration*/  {
+}
+abstract class N1b extends core::Object /*isMixinDeclaration*/  {
+}
+abstract class _N2&A&TAlias extends core::Object implements self::A /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_N2&A&TAlias
+    : super core::Object::•()
+    ;
+}
+abstract class N2 extends self::_N2&A&TAlias /*isMixinDeclaration*/  {
+}
+abstract class N3 extends self::A /*isMixinDeclaration*/  {
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/old_version.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/old_version.dart.weak.modular.expect
new file mode 100644
index 0000000..104aeb2
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/old_version.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/old_version.dart:7:11: Error: Can't create typedef from non-function type.
+// typedef A = int;
+//           ^
+//
+import self as self;
+
+typedef A = invalid-type;
+static method main() → void {}
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/unaliased_bounds_checks_in_constructor_calls.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/unaliased_bounds_checks_in_constructor_calls.dart.weak.modular.expect
new file mode 100644
index 0000000..1dd5191
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/unaliased_bounds_checks_in_constructor_calls.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/unaliased_bounds_checks_in_constructor_calls.dart:9:7: Error: Type argument 'dynamic' doesn't conform to the bound 'num' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+//   new A<dynamic, String>();
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/unaliased_bounds_checks_in_constructor_calls.dart:6:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef A<X extends num, Y> = C<X>;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef A<X extends core::num, unrelated Y extends core::Object? = dynamic> = self::C<X>;
+class C<X extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::X%>
+    : super core::Object::•()
+    ;
+}
+static method foo() → dynamic {
+  new self::C::•<dynamic>();
+}
+static method main() → dynamic {}
+static method _#A#new#tearOff<X extends core::num, unrelated Y extends core::Object? = dynamic>() → self::C<self::_#A#new#tearOff::X>
+  return new self::C::•<self::_#A#new#tearOff::X>();
diff --git a/pkg/front_end/testcases/nonfunction_type_aliases/unaliased_bounds_checks_in_constructor_calls_with_parts_main.dart.weak.modular.expect b/pkg/front_end/testcases/nonfunction_type_aliases/unaliased_bounds_checks_in_constructor_calls_with_parts_main.dart.weak.modular.expect
new file mode 100644
index 0000000..f7eab09
--- /dev/null
+++ b/pkg/front_end/testcases/nonfunction_type_aliases/unaliased_bounds_checks_in_constructor_calls_with_parts_main.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+
+import "org-dartlang-testcase:///unaliased_bounds_checks_in_constructor_calls_with_parts_lib.dart";
+
+static method main() → dynamic {}
+
+library unaliased_bounds_checks_in_constructor_calls_with_parts_lib /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/nonfunction_type_aliases/unaliased_bounds_checks_in_constructor_calls_with_parts_part_lib.dart:11:7: Error: Type argument 'dynamic' doesn't conform to the bound 'num' of the type variable 'X' on 'A'.
+// Try changing type arguments so that they conform to the bounds.
+//   new A<dynamic, String>();
+//       ^
+// pkg/front_end/testcases/nonfunction_type_aliases/unaliased_bounds_checks_in_constructor_calls_with_parts_part_lib.dart:8:11: Context: This is the type variable whose bound isn't conformed to.
+// typedef A<X extends num, Y> = C<X>;
+//           ^
+//
+import self as self2;
+import "dart:core" as core;
+
+part ./unaliased_bounds_checks_in_constructor_calls_with_parts_part_lib.dart;
+typedef A<X extends core::num, unrelated Y extends core::Object? = dynamic> = self2::C<X>;
+class C<X extends core::Object? = dynamic> extends core::Object { // from org-dartlang-testcase:///unaliased_bounds_checks_in_constructor_calls_with_parts_part_lib.dart
+  synthetic constructor •() → self2::C<self2::C::X%>
+    : super core::Object::•()
+    ;
+}
+static method /* from org-dartlang-testcase:///unaliased_bounds_checks_in_constructor_calls_with_parts_part_lib.dart */ foo() → dynamic {
+  new self2::C::•<dynamic>();
+}
+static method /* from org-dartlang-testcase:///unaliased_bounds_checks_in_constructor_calls_with_parts_part_lib.dart */ _#A#new#tearOff<X extends core::num, unrelated Y extends core::Object? = dynamic>() → self2::C<self2::_#A#new#tearOff::X>
+  return new self2::C::•<self2::_#A#new#tearOff::X>();
diff --git a/pkg/front_end/testcases/rasta/abstract_constructor.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/abstract_constructor.dart.weak.modular.expect
new file mode 100644
index 0000000..bbfdd17
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/abstract_constructor.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/abstract_constructor.dart:8:7: Error: The class 'C' is abstract and can't be instantiated.
+//   new C();
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  throw new core::AbstractClassInstantiationError::•("C");
+}
diff --git a/pkg/front_end/testcases/rasta/bad_constructor_redirection.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/bad_constructor_redirection.dart.weak.modular.expect
new file mode 100644
index 0000000..c1d156b
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/bad_constructor_redirection.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/bad_constructor_redirection.dart:6:21: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//   const C() : this.x(1);
+//                     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::C*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/rasta/bad_constructor_redirection.dart:6:21: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+  const C() : this.x(1);
+                    ^"
+    ;
+  const constructor x() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::C::•();
+  invalid-expression "pkg/front_end/testcases/rasta/bad_constructor_redirection.dart:6:21: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+  const C() : this.x(1);
+                    ^";
+}
+
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///bad_constructor_redirection.dart:
+- C. (from org-dartlang-testcase:///bad_constructor_redirection.dart:6:9)
diff --git a/pkg/front_end/testcases/rasta/bad_continue.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/bad_continue.dart.weak.modular.expect
new file mode 100644
index 0000000..755a3f3
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/bad_continue.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/bad_continue.dart:6:3: Error: A continue statement can't be used outside of a loop or switch statement.
+// Try removing the continue statement.
+//   continue here;
+//   ^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/bad_continue.dart:6:12: Error: Can't find label 'here'.
+// Try defining the label, or correcting the name to match an existing label.
+//   continue here;
+//            ^
+//
+// pkg/front_end/testcases/rasta/bad_continue.dart:7:10: Error: A continue statement can't be used outside of a loop or switch statement.
+// Try removing the continue statement.
+//   label: continue label;
+//          ^^^^^^^^
+//
+import self as self;
+
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/rasta/bad_continue.dart:6:12: Error: Can't find label 'here'.
+Try defining the label, or correcting the name to match an existing label.
+  continue here;
+           ^";
+  #L1:
+  break #L1;
+}
diff --git a/pkg/front_end/testcases/rasta/bad_default_constructor.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/bad_default_constructor.dart.weak.modular.expect
new file mode 100644
index 0000000..864e20e
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/bad_default_constructor.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/bad_default_constructor.dart:13:9: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+// Try using a constructor or factory that is 'const'.
+//   const B();
+//         ^
+//
+// pkg/front_end/testcases/rasta/bad_default_constructor.dart:9:7: Error: The superclass, 'A', has no unnamed constructor that takes no arguments.
+// class B extends A {}
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  constructor •(dynamic x) → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : invalid-initializer
+    ;
+}
+static method main() → dynamic {
+  new self::B::•();
+  invalid-expression "pkg/front_end/testcases/rasta/bad_default_constructor.dart:13:9: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+Try using a constructor or factory that is 'const'.
+  const B();
+        ^";
+}
diff --git a/pkg/front_end/testcases/rasta/bad_explicit_super_constructor.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/bad_explicit_super_constructor.dart.weak.modular.expect
new file mode 100644
index 0000000..f42bd18
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/bad_explicit_super_constructor.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/bad_explicit_super_constructor.dart:10:20: Error: Too few positional arguments: 1 required, 0 given.
+//   const B() : super();
+//                    ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  constructor •(dynamic x) → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A /*hasConstConstructor*/  {
+  const constructor •() → self::B*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/rasta/bad_explicit_super_constructor.dart:10:20: Error: Too few positional arguments: 1 required, 0 given.
+  const B() : super();
+                   ^"
+    ;
+}
+static method main() → dynamic {
+  new self::B::•();
+  invalid-expression "pkg/front_end/testcases/rasta/bad_explicit_super_constructor.dart:10:20: Error: Too few positional arguments: 1 required, 0 given.
+  const B() : super();
+                   ^";
+}
+
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///bad_explicit_super_constructor.dart:
+- B. (from org-dartlang-testcase:///bad_explicit_super_constructor.dart:10:9)
diff --git a/pkg/front_end/testcases/rasta/bad_implicit_super_constructor.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/bad_implicit_super_constructor.dart.weak.modular.expect
new file mode 100644
index 0000000..add2a41
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/bad_implicit_super_constructor.dart.weak.modular.expect
@@ -0,0 +1,51 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/bad_implicit_super_constructor.dart:10:9: Error: The superclass, 'A', has no unnamed constructor that takes no arguments.
+//   const B();
+//         ^
+//
+// pkg/front_end/testcases/rasta/bad_implicit_super_constructor.dart:6:10: Error: 'x' isn't an instance field of this class.
+//   A(this.x);
+//          ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  constructor •(dynamic x) → self::A*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/rasta/bad_implicit_super_constructor.dart:6:10: Error: 'x' isn't an instance field of this class.
+  A(this.x);
+         ^"
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A /*hasConstConstructor*/  {
+  const constructor •() → self::B*
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/rasta/bad_implicit_super_constructor.dart:10:9: Error: The superclass, 'A', has no unnamed constructor that takes no arguments.
+  const B();
+        ^"
+    ;
+}
+static method main() → dynamic {
+  new self::B::•();
+  invalid-expression "pkg/front_end/testcases/rasta/bad_implicit_super_constructor.dart:10:9: Error: The superclass, 'A', has no unnamed constructor that takes no arguments.
+  const B();
+        ^";
+}
+
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///bad_implicit_super_constructor.dart:
+- B. (from org-dartlang-testcase:///bad_implicit_super_constructor.dart:10:9)
diff --git a/pkg/front_end/testcases/rasta/bad_interpolation.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/bad_interpolation.dart.weak.modular.expect
new file mode 100644
index 0000000..e09a8ab
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/bad_interpolation.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/bad_interpolation.dart:6:13: Error: String starting with " must end with ".
+//   print(" $x.);
+//             ^^^
+//
+// pkg/front_end/testcases/rasta/bad_interpolation.dart:6:8: Error: Can't find ')' to match '('.
+//   print(" $x.);
+//        ^
+//
+// pkg/front_end/testcases/rasta/bad_interpolation.dart:6:12: Error: Undefined name 'x'.
+//   print(" $x.);
+//            ^
+//
+// pkg/front_end/testcases/rasta/bad_interpolation.dart:6:13: Error: Expected ';' after this.
+//   print(" $x.);
+//             ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::print(" ${invalid-expression "pkg/front_end/testcases/rasta/bad_interpolation.dart:6:12: Error: Undefined name 'x'.
+  print(\" \$x.);
+           ^"}.);\"");
+}
diff --git a/pkg/front_end/testcases/rasta/bad_redirection.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/bad_redirection.dart.weak.modular.expect
new file mode 100644
index 0000000..e0af5b5
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/bad_redirection.dart.weak.modular.expect
@@ -0,0 +1,47 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/bad_redirection.dart:6:9: Error: Only factory constructor can specify '=' redirection.
+// Try making this a factory constructor, or remove the redirection.
+//   Foo() = Bar;
+//         ^
+//
+// pkg/front_end/testcases/rasta/bad_redirection.dart:6:9: Error: Expected a function body or '=>'.
+// Try adding {}.
+//   Foo() = Bar;
+//         ^
+//
+// pkg/front_end/testcases/rasta/bad_redirection.dart:6:11: Error: Constructors can't have a return type.
+// Try removing the return type.
+//   Foo() = Bar;
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  constructor •() → self::Foo*
+    : super core::Object::•()
+    invalid-expression "pkg/front_end/testcases/rasta/bad_redirection.dart:6:11: Error: Constructors can't have a return type.
+Try removing the return type.
+  Foo() = Bar;
+          ^";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar extends self::Foo {
+  static factory •() → self::Bar*
+    return null;
+}
+static method main() → dynamic {
+  new self::Foo::•();
+}
diff --git a/pkg/front_end/testcases/rasta/bad_setter_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/bad_setter_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..09e385e1
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/bad_setter_initializer.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/bad_setter_initializer.dart:6:9: Error: 'field' isn't an instance field of this class.
+//   C() : field = null;
+//         ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  constructor •() → self::C*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/rasta/bad_setter_initializer.dart:6:9: Error: 'field' isn't an instance field of this class.
+  C() : field = null;
+        ^^^^^"
+    ;
+  set field(dynamic value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::C::•();
+}
diff --git a/pkg/front_end/testcases/rasta/bad_unicode.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/bad_unicode.dart.weak.modular.expect
new file mode 100644
index 0000000..749bace
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/bad_unicode.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/bad_unicode.dart:6:10: Error: An escape sequence starting with '\u' must be followed by 4 hexadecimal digits or from 1 to 6 digits between '{' and '}'.
+//   print("\u00"); // Bad Unicode escape, must have 4 hex digits.
+//          ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::print("\\u00");
+}
diff --git a/pkg/front_end/testcases/rasta/breaking_bad.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/breaking_bad.dart.weak.modular.expect
new file mode 100644
index 0000000..b2fb346
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/breaking_bad.dart.weak.modular.expect
@@ -0,0 +1,19 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/breaking_bad.dart:6:3: Error: A break statement can't be used outside of a loop or switch statement.
+// Try removing the break statement.
+//   break;
+//   ^^^^^
+//
+import self as self;
+
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/rasta/breaking_bad.dart:6:3: Error: A break statement can't be used outside of a loop or switch statement.
+Try removing the break statement.
+  break;
+  ^";
+  #L1:
+  break #L1;
+}
diff --git a/pkg/front_end/testcases/rasta/cascades.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/cascades.dart.weak.modular.expect
new file mode 100644
index 0000000..73ffa41
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/cascades.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method add(dynamic x) → dynamic
+    return x;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::A* a = new self::A::•();
+  function f(dynamic x) → dynamic
+    return x;
+  let final self::A* #t1 = a in block {
+    #t1.{self::A::add}(f){(dynamic) →* dynamic}{dynamic}.call("WHAT");
+  } =>#t1;
+}
diff --git a/pkg/front_end/testcases/rasta/class_hierarchy.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/class_hierarchy.dart.weak.modular.expect
new file mode 100644
index 0000000..b641197
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/class_hierarchy.dart.weak.modular.expect
@@ -0,0 +1,105 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/class_hierarchy.dart:5:17: Error: Type 'Missing' not found.
+// class A extends Missing {}
+//                 ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/class_hierarchy.dart:7:20: Error: Type 'Missing' not found.
+// class B implements Missing {}
+//                    ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/class_hierarchy.dart:9:23: Error: Type 'Missing' not found.
+// class C = Object with Missing;
+//                       ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/class_hierarchy.dart:9:7: Error: The type 'Missing' can't be mixed in.
+// class C = Object with Missing;
+//       ^
+//
+// pkg/front_end/testcases/rasta/class_hierarchy.dart:12:17: Error: Couldn't find constructor 'Missing'.
+//   factory D() = Missing;
+//                 ^
+//
+// pkg/front_end/testcases/rasta/class_hierarchy.dart:12:17: Error: Redirection constructor target not found: 'Missing'
+//   factory D() = Missing;
+//                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object /*hasConstConstructor*/  {
+  const synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  static factory •() → self::D*
+    return invalid-expression "pkg/front_end/testcases/rasta/class_hierarchy.dart:12:17: Error: Redirection constructor target not found: 'Missing'
+  factory D() = Missing;
+                ^";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {
+  new self::A::•();
+  new self::B::•();
+  new self::C::•();
+  invalid-expression "pkg/front_end/testcases/rasta/class_hierarchy.dart:12:17: Error: Redirection constructor target not found: 'Missing'
+  factory D() = Missing;
+                ^";
+}
+
+constants  {
+  #C1 = constructor-tearoff self::D::•
+}
diff --git a/pkg/front_end/testcases/rasta/class_member.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/class_member.dart.weak.modular.expect
new file mode 100644
index 0000000..e692877
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/class_member.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  field dynamic field1 = null;
+  field dynamic field2 = null;
+  field dynamic field3 = null;
+  constructor constructor1() → self::Foo*
+    : super core::Object::•()
+    ;
+  constructor constructor2() → self::Foo*
+    : super core::Object::•()
+    ;
+  constructor constructor3() → self::Foo*
+    : super core::Object::•()
+    ;
+  method a() → dynamic {}
+  method b() → dynamic {}
+  method c() → dynamic {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/rasta/constant_get_and_invoke.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/constant_get_and_invoke.dart.weak.modular.expect
new file mode 100644
index 0000000..ada899d
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/constant_get_and_invoke.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/constant_get_and_invoke.dart:8:4: Error: The method 'call' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing method, or defining a method named 'call'.
+//   c();
+//    ^
+//
+import self as self;
+import "dart:core" as core;
+
+static const field core::int* c = #C1;
+static method main() → dynamic {
+  #C1;
+  invalid-expression "pkg/front_end/testcases/rasta/constant_get_and_invoke.dart:8:4: Error: The method 'call' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing method, or defining a method named 'call'.
+  c();
+   ^" in #C1{<unresolved>}.call();
+}
+
+constants  {
+  #C1 = 1
+}
diff --git a/pkg/front_end/testcases/rasta/deferred_load.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/deferred_load.dart.weak.modular.expect
new file mode 100644
index 0000000..d01ac3d
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/deferred_load.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library;
+import self as self;
+import "dart:async" as asy;
+
+import "org-dartlang-testcase:///deferred_lib.dart" deferred as lib;
+
+static method main() → dynamic {
+  #C1;
+  LoadLibrary(lib);
+}
+static method _#loadLibrary_lib() → asy::Future<dynamic>*
+  return LoadLibrary(lib);
+
+library deferred_lib;
+import self as self2;
+
+static method foo() → dynamic
+  return null;
+
+constants  {
+  #C1 = static-tearoff self::_#loadLibrary_lib
+}
diff --git a/pkg/front_end/testcases/rasta/duplicated_mixin.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/duplicated_mixin.dart.weak.modular.expect
new file mode 100644
index 0000000..3324351
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/duplicated_mixin.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Mixin extends core::Object {
+  field dynamic field = null;
+  synthetic constructor •() → self::Mixin*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _A&Object&Mixin = core::Object with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A&Object&Mixin*
+    : super core::Object::•()
+    ;
+  mixin-super-stub get field() → dynamic
+    return super.{self::Mixin::field};
+  mixin-super-stub set field(dynamic value) → void
+    return super.{self::Mixin::field} = value;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _A&Object&Mixin&Mixin = self::_A&Object&Mixin with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_A&Object&Mixin&Mixin*
+    : super self::_A&Object&Mixin::•()
+    ;
+  mixin-super-stub get field() → dynamic
+    return super.{self::Mixin::field};
+  mixin-super-stub set field(dynamic value) → void
+    return super.{self::Mixin::field} = value;
+}
+class A extends self::_A&Object&Mixin&Mixin {
+  synthetic constructor •() → self::A*
+    : super self::_A&Object&Mixin&Mixin::•()
+    ;
+}
diff --git a/pkg/front_end/testcases/rasta/enum.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/enum.dart.weak.modular.expect
new file mode 100644
index 0000000..71a6850
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/enum.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::Foo*>* values = #C7;
+  static const field self::Foo* ec1 = #C3;
+  static const field self::Foo* ec2 = #C6;
+  const constructor •(core::int* index, core::String* name) → self::Foo*
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String*
+    return "Foo.${this.{core::_Enum::_name}{core::String}}";
+  abstract member-signature get index() → core::int*; -> core::_Enum::index
+  abstract member-signature get _name() → core::String*; -> core::_Enum::_name
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+  #C2 = "ec1"
+  #C3 = self::Foo {index:#C1, _name:#C2}
+  #C4 = 1
+  #C5 = "ec2"
+  #C6 = self::Foo {index:#C4, _name:#C5}
+  #C7 = <self::Foo*>[#C3, #C6]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///enum.dart:
+- Foo. (from org-dartlang-testcase:///enum.dart:5:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:76:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/rasta/export.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/export.dart.weak.modular.expect
new file mode 100644
index 0000000..6eb1e47
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/export.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library export;
+import self as self;
+import "foo.dart" as foo;
+additionalExports = (foo::foo)
+
+export "org-dartlang-testcase:///foo.dart";
+
+
+library foo;
+import self as foo;
+import "dart:core" as core;
+
+static method foo() → dynamic {
+  core::print("Hello, World!");
+}
diff --git a/pkg/front_end/testcases/rasta/external_factory_redirection.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/external_factory_redirection.dart.weak.modular.expect
new file mode 100644
index 0000000..8b7a99d
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/external_factory_redirection.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  "Should redirect to LinkedHashMap constructor.";
+  core::Map::•<core::Symbol*, dynamic>();
+}
diff --git a/pkg/front_end/testcases/rasta/foo.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/foo.dart.weak.modular.expect
new file mode 100644
index 0000000..5f90b5a
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/foo.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library foo;
+import self as self;
+import "dart:core" as core;
+
+static method foo() → dynamic {
+  core::print("Hello, World!");
+}
diff --git a/pkg/front_end/testcases/rasta/for_loop.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/for_loop.dart.weak.modular.expect
new file mode 100644
index 0000000..94b2d41
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/for_loop.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::int* c = new core::DateTime::now().{core::DateTime::millisecondsSinceEpoch}{core::int*};
+  for (core::int* i = 0; i.{core::num::<}(100){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+    core::print(let final core::int* #t1 = i in let final core::int* #t2 = i = #t1.{core::num::+}(1){(core::num*) →* core::int*} in #t1);
+  }
+  for (core::int* i = 0; i.{core::num::<}(100){(core::num*) →* core::bool*}; c.{core::num::<}(42){(core::num*) →* core::bool*} ?{core::int*} throw "fisk" : let final core::int* #t3 = i in let final core::int* #t4 = i = #t3.{core::num::+}(1){(core::num*) →* core::int*} in #t3) {
+    core::print(let final core::int* #t5 = i in let final core::int* #t6 = i = #t5.{core::num::+}(1){(core::num*) →* core::int*} in #t5);
+  }
+}
diff --git a/pkg/front_end/testcases/rasta/generic_factory.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/generic_factory.dart.weak.modular.expect
new file mode 100644
index 0000000..05e4007
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/generic_factory.dart.weak.modular.expect
@@ -0,0 +1,150 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/generic_factory.dart:16:19: Error: Couldn't find constructor 'Missing'.
+//   factory A.c() = Missing;
+//                   ^
+//
+// pkg/front_end/testcases/rasta/generic_factory.dart:16:19: Error: Redirection constructor target not found: 'Missing'
+//   factory A.c() = Missing;
+//                   ^
+//
+// pkg/front_end/testcases/rasta/generic_factory.dart:15:19: Error: The constructor function type 'B<C1> Function()' isn't a subtype of 'A<T> Function()'.
+//  - 'B' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+//  - 'C1' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+//  - 'A' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+//   factory A.b() = B<C1>.a;
+//                   ^
+//
+// pkg/front_end/testcases/rasta/generic_factory.dart:23:19: Error: The constructor function type 'C<C2> Function()' isn't a subtype of 'B<S> Function()'.
+//  - 'C' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+//  - 'C2' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+//  - 'B' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+//   factory B.b() = C<C2>;
+//                   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C1 extends core::Object {
+  synthetic constructor •() → self::C1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C2 extends core::Object {
+  synthetic constructor •() → self::C2*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C3 extends core::Object {
+  synthetic constructor •() → self::C3*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A<T extends core::Object* = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1, #C2, #C3];
+  constructor internal() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  static factory a<T extends core::Object* = dynamic>() → self::A<self::A::a::T*>*
+    return self::B::a<self::A::a::T*>();
+  static factory b<T extends core::Object* = dynamic>() → self::A<self::A::b::T*>*
+    return invalid-expression "pkg/front_end/testcases/rasta/generic_factory.dart:15:19: Error: The constructor function type 'B<C1> Function()' isn't a subtype of 'A<T> Function()'.
+ - 'B' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+ - 'C1' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+ - 'A' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+  factory A.b() = B<C1>.a;
+                  ^";
+  static factory c<T extends core::Object* = dynamic>() → self::A<self::A::c::T*>*
+    return invalid-expression "pkg/front_end/testcases/rasta/generic_factory.dart:16:19: Error: Redirection constructor target not found: 'Missing'
+  factory A.c() = Missing;
+                  ^";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<S extends core::Object* = dynamic> extends self::A<self::B::S*> {
+  static final field dynamic _redirecting# = <dynamic>[#C4, #C5];
+  constructor internal() → self::B<self::B::S*>*
+    : super self::A::internal()
+    ;
+  static factory a<S extends core::Object* = dynamic>() → self::B<self::B::a::S*>*
+    return new self::C::•<self::B::a::S*>();
+  static factory b<S extends core::Object* = dynamic>() → self::B<self::B::b::S*>*
+    return invalid-expression "pkg/front_end/testcases/rasta/generic_factory.dart:23:19: Error: The constructor function type 'C<C2> Function()' isn't a subtype of 'B<S> Function()'.
+ - 'C' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+ - 'C2' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+ - 'B' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+  factory B.b() = C<C2>;
+                  ^";
+}
+class C<U extends core::Object* = dynamic> extends self::B<self::C::U*> {
+  constructor •() → self::C<self::C::U*>*
+    : super self::B::internal()
+    ;
+}
+static method main() → dynamic {
+  new self::C::•<self::C3*>();
+  invalid-expression "pkg/front_end/testcases/rasta/generic_factory.dart:15:19: Error: The constructor function type 'B<C1> Function()' isn't a subtype of 'A<T> Function()'.
+ - 'B' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+ - 'C1' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+ - 'A' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+  factory A.b() = B<C1>.a;
+                  ^";
+  new self::C::•<self::C3*>();
+  invalid-expression "pkg/front_end/testcases/rasta/generic_factory.dart:23:19: Error: The constructor function type 'C<C2> Function()' isn't a subtype of 'B<S> Function()'.
+ - 'C' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+ - 'C2' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+ - 'B' is from 'pkg/front_end/testcases/rasta/generic_factory.dart'.
+  factory B.b() = C<C2>;
+                  ^";
+  invalid-expression "pkg/front_end/testcases/rasta/generic_factory.dart:16:19: Error: Redirection constructor target not found: 'Missing'
+  factory A.c() = Missing;
+                  ^";
+}
+
+constants  {
+  #C1 = constructor-tearoff self::A::a
+  #C2 = constructor-tearoff self::A::b
+  #C3 = constructor-tearoff self::A::c
+  #C4 = constructor-tearoff self::B::a
+  #C5 = constructor-tearoff self::B::b
+}
diff --git a/pkg/front_end/testcases/rasta/hello.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/hello.dart.weak.modular.expect
new file mode 100644
index 0000000..fea7b39
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/hello.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::print("Hello, World!");
+}
diff --git a/pkg/front_end/testcases/rasta/import_export.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/import_export.dart.weak.modular.expect
new file mode 100644
index 0000000..18b095f
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/import_export.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library;
+import self as self;
+import "foo.dart" as foo;
+
+import "org-dartlang-testcase:///export.dart";
+
+static method main() → dynamic {
+  foo::foo();
+}
+
+library export;
+import self as self2;
+import "foo.dart" as foo;
+additionalExports = (foo::foo)
+
+export "org-dartlang-testcase:///foo.dart";
+
+
+library foo;
+import self as foo;
+import "dart:core" as core;
+
+static method foo() → dynamic {
+  core::print("Hello, World!");
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000001.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000001.dart.weak.modular.expect
new file mode 100644
index 0000000..aa235f1
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000001.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/issue_000001.dart:11:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//   test0(0, 1);
+//        ^
+// pkg/front_end/testcases/rasta/issue_000001.dart:5:1: Context: Found this candidate, but the arguments don't match.
+// test0(x) {
+// ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test0(dynamic x) → dynamic {
+  core::print("test0");
+}
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/rasta/issue_000001.dart:11:8: Error: Too many positional arguments: 1 allowed, but 2 found.
+Try removing the extra positional arguments.
+  test0(0, 1);
+       ^";
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000002.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000002.dart.weak.modular.expect
new file mode 100644
index 0000000..90a6469
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000002.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+import "dart:typed_data" as typ;
+
+import "dart:typed_data";
+import "package:expect/expect.dart";
+
+class Foo extends core::Object {
+  final field dynamic value;
+  constructor •(dynamic value) → self::Foo*
+    : self::Foo::value = value, super core::Object::•() {}
+  static factory fac(dynamic value) → self::Foo* {
+    return new self::Foo::•(value);
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::List<core::int*>* list = <core::int*>[1, 2, 3];
+static method main() → dynamic {
+  exp::Expect::isTrue(typ::Uint8List::fromList(self::list).{core::List::[]}(1){(core::int*) →* core::int*} =={core::num::==}{(core::Object*) →* core::bool*} 2);
+  exp::Expect::isTrue(self::Foo::fac(10).{self::Foo::value}{dynamic} =={core::Object::==}{(core::Object*) →* core::bool*} 10);
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000004.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000004.dart.weak.modular.expect
new file mode 100644
index 0000000..8b66203
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000004.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static field dynamic global;
+static method fact4() → dynamic {
+  core::int* f = 1;
+  for (core::int* n in <core::int*>[1, 2, 3, 4]) {
+    f = f.{core::num::*}(n){(core::num*) →* core::int*};
+  }
+  return f;
+}
+static method fact5() → dynamic {
+  core::int* f = 1;
+  dynamic n;
+  for (final dynamic #t1 in <dynamic>[1, 2, 3, 4, 5]) {
+    n = #t1;
+    f = f.{core::num::*}(n as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*} as{TypeError} core::int*;
+  }
+  return f;
+}
+static method fact6() → dynamic {
+  core::int* f = 1;
+  for (final dynamic #t2 in <dynamic>[1, 2, 3, 4, 5, 6]) {
+    self::global = #t2;
+    f = f.{core::num::*}(self::global as{TypeError,ForDynamic} core::num*){(core::num*) →* core::num*} as{TypeError} core::int*;
+  }
+  return f;
+}
+static method main() → dynamic {
+  exp::Expect::isTrue(self::fact4() =={core::Object::==}{(core::Object*) →* core::bool*} 24);
+  exp::Expect::isTrue(self::fact5() =={core::Object::==}{(core::Object*) →* core::bool*} 120);
+  exp::Expect::isTrue(self::fact6() =={core::Object::==}{(core::Object*) →* core::bool*} 720);
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000006.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000006.dart.weak.modular.expect
new file mode 100644
index 0000000..d8e5d49
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000006.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static field core::List<core::int*>* list = <core::int*>[1, 2, 3];
+static method main() → dynamic {
+  self::list.{core::List::add}(1){(core::int*) →* void};
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000007.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000007.dart.weak.modular.expect
new file mode 100644
index 0000000..6cd1688
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000007.dart.weak.modular.expect
@@ -0,0 +1,51 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Base extends core::Object {
+  synthetic constructor •() → self::Base*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Mixin extends core::Object {
+  synthetic constructor •() → self::Mixin*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic
+    return core::print("foo");
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Sub&Base&Mixin = self::Base with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Sub&Base&Mixin*
+    : super self::Base::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::Mixin::foo}();
+}
+class Sub extends self::_Sub&Base&Mixin {
+  synthetic constructor •() → self::Sub*
+    : super self::_Sub&Base&Mixin::•()
+    ;
+}
+static method main() → dynamic {
+  new self::Sub::•().{self::_Sub&Base&Mixin::foo}(){() →* dynamic};
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000008.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000008.dart.weak.modular.expect
new file mode 100644
index 0000000..c1f058b
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000008.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  final field dynamic x;
+  constructor •(dynamic x) → self::C*
+    : self::C::x = x, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::C::•(42);
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000011.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000011.dart.weak.modular.expect
new file mode 100644
index 0000000..aa88a42
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000011.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  try {
+    core::print(42);
+  }
+  finally {
+    core::print(87);
+  }
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000012.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000012.dart.weak.modular.expect
new file mode 100644
index 0000000..e6e3429
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000012.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field dynamic field = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  method m() → dynamic {
+    super.{self::A::field} = 42;
+  }
+}
+static method main() → dynamic {
+  new self::B::•().{self::B::m}(){() →* dynamic};
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000025.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000025.dart.weak.modular.expect
new file mode 100644
index 0000000..3be7ccc
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000025.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static get x() → dynamic
+  return 42;
+static set x(dynamic val) → void {}
+static method main() → dynamic {
+  core::print(self::x);
+  core::print(self::x = 87);
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000026.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000026.dart.weak.modular.expect
new file mode 100644
index 0000000..9e127fd
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000026.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field dynamic a = null;
+  field core::int* b = 0;
+  field core::int* c = 1.{core::num::+}(2){(core::num*) →* core::int*};
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends core::Object {
+  field dynamic a = null;
+  field core::int* b = 1;
+  field core::int* c = 2.{core::num::-}(3){(core::num*) →* core::int*};
+  constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::C::•();
+  new self::D::•();
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000031.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000031.dart.weak.modular.expect
new file mode 100644
index 0000000..5147d08
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000031.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/issue_000031.dart:8:3: Error: A prefix can't be used as an expression.
+//   math..toString();
+//   ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "dart:math" as math;
+
+static method main() → dynamic {
+  let final invalid-type #t1 = invalid-expression "pkg/front_end/testcases/rasta/issue_000031.dart:8:3: Error: A prefix can't be used as an expression.
+  math..toString();
+  ^^^^" in block {
+    #t1.{core::Object::toString}(){() →* core::String*};
+  } =>#t1;
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000032.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000032.dart.weak.modular.expect
new file mode 100644
index 0000000..a34f230
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000032.dart.weak.modular.expect
@@ -0,0 +1,63 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/issue_000032.dart:7:1: Error: Expected a type, but got '}'.
+// }
+// ^
+//
+// pkg/front_end/testcases/rasta/issue_000032.dart:7:1: Error: Expected an identifier, but got '}'.
+// Try inserting an identifier before '}'.
+// }
+// ^
+//
+// pkg/front_end/testcases/rasta/issue_000032.dart:6:4: Error: Expected ';' after this.
+//   C<
+//    ^
+//
+// pkg/front_end/testcases/rasta/issue_000032.dart:11:1: Error: Expected an identifier, but got '}'.
+// Try inserting an identifier before '}'.
+// }
+// ^
+//
+// pkg/front_end/testcases/rasta/issue_000032.dart:10:4: Error: Expected ';' after this.
+//   C<
+//    ^
+//
+// pkg/front_end/testcases/rasta/issue_000032.dart:10:4: Error: The operator '<' isn't defined for the class 'Type'.
+//  - 'Type' is from 'dart:core'.
+// Try correcting the operator to an existing operator, or defining a '<' operator.
+//   C<
+//    ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/rasta/issue_000032.dart:10:4: Error: The operator '<' isn't defined for the class 'Type'.
+ - 'Type' is from 'dart:core'.
+Try correcting the operator to an existing operator, or defining a '<' operator.
+  C<
+   ^" in #C1{<unresolved>}.<(invalid-expression "pkg/front_end/testcases/rasta/issue_000032.dart:11:1: Error: This couldn't be parsed.
+}
+^");
+}
+
+constants  {
+  #C1 = TypeLiteralConstant(self::C*)
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000033.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000033.dart.weak.modular.expect
new file mode 100644
index 0000000..e288dc4
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000033.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/issue_000033.dart:5:2: Error: Couldn't find constructor 'JS'.
+// @JS()
+//  ^^
+//
+import self as self;
+
+@invalid-expression "pkg/front_end/testcases/rasta/issue_000033.dart:5:2: Error: Couldn't find constructor 'JS'.
+@JS()
+ ^^"
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/rasta/issue_000034.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000034.dart.weak.modular.expect
new file mode 100644
index 0000000..58227f9
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000034.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/issue_000034.dart:6:15: Error: Expected an assignment after the field name.
+// To initialize a field, use the syntax 'name = value'.
+//   const C() : this.x;
+//               ^^^^
+//
+// pkg/front_end/testcases/rasta/issue_000034.dart:6:15: Error: Can't access 'this' in a field initializer.
+//   const C() : this.x;
+//               ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object /*hasConstConstructor*/  {
+  const constructor •() → self::C*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/rasta/issue_000034.dart:6:15: Error: This couldn't be parsed.
+  const C() : this.x;
+              ^"
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/rasta/issue_000034.dart:6:15: Error: This couldn't be parsed.
+  const C() : this.x;
+              ^";
+}
+
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue_000034.dart:
+- C. (from org-dartlang-testcase:///issue_000034.dart:6:9)
diff --git a/pkg/front_end/testcases/rasta/issue_000035.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000035.dart.weak.modular.expect
new file mode 100644
index 0000000..d27cbe4
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000035.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/issue_000035.dart:5:10: Error: The non-ASCII character 'æ' (U+00E6) can't be used in identifiers, only in strings and comments.
+// Try using an US-ASCII letter, a digit, '_' (an underscore), or '$' (a dollar sign).
+// class C {æøC();}
+//          ^
+//
+// pkg/front_end/testcases/rasta/issue_000035.dart:5:11: Error: The non-ASCII character 'ø' (U+00F8) can't be used in identifiers, only in strings and comments.
+// Try using an US-ASCII letter, a digit, '_' (an underscore), or '$' (a dollar sign).
+// class C {æøC();}
+//           ^
+//
+// pkg/front_end/testcases/rasta/issue_000035.dart:5:7: Error: The non-abstract class 'C' is missing implementations for these members:
+//  - C.æøC
+// Try to either
+//  - provide an implementation,
+//  - inherit an implementation from a superclass or mixin,
+//  - mark the class as abstract, or
+//  - provide a 'noSuchMethod' implementation.
+//
+// class C {æøC();}
+//       ^
+// pkg/front_end/testcases/rasta/issue_000035.dart:5:10: Context: 'C.æøC' is defined here.
+// class C {æøC();}
+//          ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract method æøC() → dynamic;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/rasta/issue_000035a.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000035a.dart.weak.modular.expect
new file mode 100644
index 0000000..ffef0ea
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000035a.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/issue_000035a.dart:5:9: Error: The non-ASCII space character U+2028 can only be used in strings and comments.
+// class C{  C();}
+//         ^
+//
+// pkg/front_end/testcases/rasta/issue_000035a.dart:5:10: Error: The non-ASCII space character U+2028 can only be used in strings and comments.
+// class C{  C();}
+//          ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/rasta/issue_000036.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000036.dart.weak.modular.expect
new file mode 100644
index 0000000..255d67d
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000036.dart.weak.modular.expect
@@ -0,0 +1,21 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/issue_000036.dart:5:14: Error: Expected an identifier, but got '-'.
+// Try inserting an identifier before '-'.
+// main() => a. - 5;
+//              ^
+//
+// pkg/front_end/testcases/rasta/issue_000036.dart:5:14: Error: Expected an identifier, but got ''.
+// Try inserting an identifier before ''.
+// main() => a. - 5;
+//              ^
+//
+import self as self;
+
+static method main() → dynamic
+  return invalid-expression "pkg/front_end/testcases/rasta/issue_000036.dart:5:14: Error: Expected an identifier, but got ''.
+Try inserting an identifier before ''.
+main() => a. - 5;
+             ^"{<invalid>}.-(5);
diff --git a/pkg/front_end/testcases/rasta/issue_000039.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000039.dart.weak.modular.expect
new file mode 100644
index 0000000..289c890
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000039.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/issue_000039.dart:10:3: Error: Expected an identifier, but got '}'.
+// Try inserting an identifier before '}'.
+//   }
+//   ^
+//
+// pkg/front_end/testcases/rasta/issue_000039.dart:10:3: Error: Expected an identifier, but got ''.
+// Try inserting an identifier before ''.
+//   }
+//   ^
+//
+// pkg/front_end/testcases/rasta/issue_000039.dart:9:15: Error: Expected ';' after this.
+//     this.a = x.
+//               ^
+//
+// pkg/front_end/testcases/rasta/issue_000039.dart:13:7: Error: The superclass, 'A', has no unnamed constructor that takes no arguments.
+// class B extends A {
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field dynamic a = null;
+  constructor •(dynamic x) → self::A*
+    : super core::Object::•() {
+    this.{self::A::a} = invalid-expression "pkg/front_end/testcases/rasta/issue_000039.dart:10:3: Error: Expected an identifier, but got ''.
+Try inserting an identifier before ''.
+  }
+  ^";
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : invalid-initializer
+    ;
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000041.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000041.dart.weak.modular.expect
new file mode 100644
index 0000000..2026340
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000041.dart.weak.modular.expect
@@ -0,0 +1,45 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/issue_000041.dart:7:9: Error: '+' is not a prefix operator.
+// Try removing '+'.
+//     use(+super);
+//         ^
+//
+// pkg/front_end/testcases/rasta/issue_000041.dart:7:10: Error: Can't use 'super' as an expression.
+// To delegate a constructor to a super constructor, put the super call as an initializer.
+//     use(+super);
+//          ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method test() → dynamic {
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/issue_000041.dart:7:9: Error: This couldn't be parsed.
+    use(+super);
+        ^"{<invalid>}.+(invalid-expression "pkg/front_end/testcases/rasta/issue_000041.dart:7:10: Error: Can't use 'super' as an expression.
+To delegate a constructor to a super constructor, put the super call as an initializer.
+    use(+super);
+         ^^^^^"));
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method use(dynamic _) → dynamic
+  return null;
+static method main() → dynamic {
+  new self::C::•().{self::C::test}(){() →* dynamic};
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000042.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000042.dart.weak.modular.expect
new file mode 100644
index 0000000..2abfb5d
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000042.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/issue_000042.dart:6:13: Error: Unexpected token ','.
+//   for (var x, y in []) {}
+//             ^
+//
+// pkg/front_end/testcases/rasta/issue_000042.dart:6:8: Error: A for-in loop can't have more than one loop variable.
+//   for (var x, y in []) {}
+//        ^^^
+//
+// pkg/front_end/testcases/rasta/issue_000042.dart:7:8: Error: A continue statement can't be used outside of a loop or switch statement.
+// Try removing the continue statement.
+//   L: { continue L; }
+//        ^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/issue_000042.dart:8:18: Error: A continue statement can't be used outside of a loop or switch statement.
+// Try removing the continue statement.
+//   L: if (true) { continue L; }
+//                  ^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  {
+    invalid-expression "pkg/front_end/testcases/rasta/issue_000042.dart:6:8: Error: A for-in loop can't have more than one loop variable.
+  for (var x, y in []) {}
+       ^^^";
+    for (final dynamic #t1 in <dynamic>[]) {
+      invalid-expression "pkg/front_end/testcases/rasta/issue_000042.dart:6:8: Error: A for-in loop can't have more than one loop variable.
+  for (var x, y in []) {}
+       ^^^";
+      dynamic x;
+      dynamic y;
+    }
+  }
+  #L1:
+  {
+    break #L1;
+  }
+  #L2:
+  if(true) {
+    break #L2;
+  }
+  #L3:
+  switch(1) {
+    #L4:
+    case #C1:
+      {
+        break #L3;
+      }
+    #L5:
+    case #C2:
+      {
+        break #L3;
+      }
+  }
+  try {
+  }
+  on core::NoSuchMethodError* catch(no-exception-var) {
+  }
+}
+
+constants  {
+  #C1 = 1
+  #C2 = 2
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000043.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000043.dart.weak.modular.expect
new file mode 100644
index 0000000..0c2f2cb
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000043.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  get x() → dynamic
+    return "${#C1}".{core::String::hashCode}{core::int*};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+constants  {
+  #C1 = TypeLiteralConstant(self::C*)
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000044.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000044.dart.weak.modular.expect
new file mode 100644
index 0000000..b0dbf3f
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000044.dart.weak.modular.expect
@@ -0,0 +1,119 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/issue_000044.dart:7:8: Error: Expected a function body or '=>'.
+// Try adding {}.
+// a b(c) = d;
+//        ^
+//
+// pkg/front_end/testcases/rasta/issue_000044.dart:14:29: Error: Only factory constructor can specify '=' redirection.
+// Try making this a factory constructor, or remove the redirection.
+//   C.missingFactoryKeyword() = C.constant;
+//                             ^
+//
+// pkg/front_end/testcases/rasta/issue_000044.dart:21:28: Error: Only factory constructor can specify '=' redirection.
+// Try making this a factory constructor, or remove the redirection.
+//   C notEvenAConstructor(a) = h;
+//                            ^
+//
+// pkg/front_end/testcases/rasta/issue_000044.dart:7:1: Error: Type 'a' not found.
+// a b(c) = d;
+// ^
+//
+// pkg/front_end/testcases/rasta/issue_000044.dart:21:30: Error: Couldn't find constructor 'h'.
+//   C notEvenAConstructor(a) = h;
+//                              ^
+//
+// pkg/front_end/testcases/rasta/issue_000044.dart:7:10: Error: Undefined name 'd'.
+// a b(c) = d;
+//          ^
+//
+// pkg/front_end/testcases/rasta/issue_000044.dart:14:29: Error: Expected a function body or '=>'.
+// Try adding {}.
+//   C.missingFactoryKeyword() = C.constant;
+//                             ^
+//
+// pkg/front_end/testcases/rasta/issue_000044.dart:14:33: Error: Member not found: 'constant'.
+//   C.missingFactoryKeyword() = C.constant;
+//                                 ^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/issue_000044.dart:14:31: Error: Constructors can't have a return type.
+// Try removing the return type.
+//   C.missingFactoryKeyword() = C.constant;
+//                               ^
+//
+// pkg/front_end/testcases/rasta/issue_000044.dart:21:28: Error: Expected a function body or '=>'.
+// Try adding {}.
+//   C notEvenAConstructor(a) = h;
+//                            ^
+//
+// pkg/front_end/testcases/rasta/issue_000044.dart:21:30: Error: The getter 'h' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/rasta/issue_000044.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'h'.
+//   C notEvenAConstructor(a) = h;
+//                              ^
+//
+// pkg/front_end/testcases/rasta/issue_000044.dart:27:15: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+// Try using a constructor or factory that is 'const'.
+//   print(const C.missingFactoryKeyword());
+//               ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object /*hasConstConstructor*/  {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  const constructor constant() → self::C*
+    : super core::Object::•()
+    ;
+  constructor missingFactoryKeyword() → self::C*
+    : super core::Object::•()
+    invalid-expression "pkg/front_end/testcases/rasta/issue_000044.dart:14:31: Error: Constructors can't have a return type.
+Try removing the return type.
+  C.missingFactoryKeyword() = C.constant;
+                              ^";
+  static factory good() → self::C*
+    return new self::C::constant();
+  method notEvenAConstructor(dynamic a) → self::C*
+    return invalid-expression "pkg/front_end/testcases/rasta/issue_000044.dart:21:30: Error: The getter 'h' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/rasta/issue_000044.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'h'.
+  C notEvenAConstructor(a) = h;
+                             ^" in this{<unresolved>}.h as{TypeError,ForDynamic} self::C*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method b(dynamic c) → invalid-type
+  return invalid-expression "pkg/front_end/testcases/rasta/issue_000044.dart:7:10: Error: Undefined name 'd'.
+a b(c) = d;
+         ^";
+static method main() → dynamic {
+  self::C* c = null;
+  core::print(#C2);
+  core::print(invalid-expression "pkg/front_end/testcases/rasta/issue_000044.dart:27:15: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+Try using a constructor or factory that is 'const'.
+  print(const C.missingFactoryKeyword());
+              ^");
+  core::print(#C2);
+  core::print(new self::C::constant().{self::C::notEvenAConstructor}(null){(dynamic) →* self::C*});
+}
+
+constants  {
+  #C1 = constructor-tearoff self::C::good
+  #C2 = self::C {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue_000044.dart:
+- C.constant (from org-dartlang-testcase:///issue_000044.dart:11:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/rasta/issue_000045.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000045.dart.weak.modular.expect
new file mode 100644
index 0000000..2622c42
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000045.dart.weak.modular.expect
@@ -0,0 +1,19 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/issue_000045.dart:5:18: Error: String starting with """ must end with """.
+// main() => """${1}
+//                  ^...
+//
+// pkg/front_end/testcases/rasta/issue_000045.dart:5:18: Error: Expected ';' after this.
+// main() => """${1}
+//                  ^...
+//
+// pkg/front_end/testcases/rasta/issue_000045.dart:6:1: Error: Unexpected token ''.
+//
+import self as self;
+
+static method main() → dynamic
+  return "${1}
+\"\"\"";
diff --git a/pkg/front_end/testcases/rasta/issue_000046.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000046.dart.weak.modular.expect
new file mode 100644
index 0000000..4625b85
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000046.dart.weak.modular.expect
@@ -0,0 +1,52 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/issue_000046.dart:6:13: Error: Expected '(' after this.
+//   C c = new Object)();
+//             ^^^^^^
+//
+// pkg/front_end/testcases/rasta/issue_000046.dart:6:19: Error: Expected ';' after this.
+//   C c = new Object)();
+//                   ^
+//
+// pkg/front_end/testcases/rasta/issue_000046.dart:6:19: Error: Expected a class member, but got ')'.
+//   C c = new Object)();
+//                   ^
+//
+// pkg/front_end/testcases/rasta/issue_000046.dart:6:20: Error: Expected an identifier, but got '('.
+// Try inserting an identifier before '('.
+//   C c = new Object)();
+//                    ^
+//
+// pkg/front_end/testcases/rasta/issue_000046.dart:6:13: Error: The constructor returns type 'Object' that isn't of expected type 'C'.
+//  - 'Object' is from 'dart:core'.
+//  - 'C' is from 'pkg/front_end/testcases/rasta/issue_000046.dart'.
+// Change the type of the object being constructed or the context in which it is used.
+//   C c = new Object)();
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field self::C* c = invalid-expression "pkg/front_end/testcases/rasta/issue_000046.dart:6:13: Error: The constructor returns type 'Object' that isn't of expected type 'C'.
+ - 'Object' is from 'dart:core'.
+ - 'C' is from 'pkg/front_end/testcases/rasta/issue_000046.dart'.
+Change the type of the object being constructed or the context in which it is used.
+  C c = new Object)();
+            ^" in new core::Object::•();
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000047.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000047.dart.weak.modular.expect
new file mode 100644
index 0000000..2ae0040
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000047.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/issue_000047.dart:5:17: Error: Expected ')' before this.
+// typedef void T(C<C>);
+//                 ^
+//
+import self as self;
+
+typedef T = (dynamic) →* void;
+static method main() → (dynamic) →* void
+  return null;
diff --git a/pkg/front_end/testcases/rasta/issue_000048.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000048.dart.weak.modular.expect
new file mode 100644
index 0000000..a297249
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000048.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::bool* v1;
+  field core::num* v2;
+  constructor •(core::bool* v1, core::num* v2) → self::A*
+    : self::A::v1 = v1, self::A::v2 = v2, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M1 extends core::Object {
+  field core::num* v2 = 0;
+  synthetic constructor •() → self::M1*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C = self::A with self::M1 {
+  synthetic constructor •(core::bool* v1, core::num* v2) → self::C*
+    : super self::A::•(v1, v2)
+    ;
+  mixin-super-stub get v2() → core::num*
+    return super.{self::M1::v2};
+  mixin-super-stub set v2(core::num* value) → void
+    return super.{self::M1::v2} = value;
+}
+static method main() → dynamic {
+  self::C* c = new self::C::•(true, 2);
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000052.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000052.dart.weak.modular.expect
new file mode 100644
index 0000000..4c2e652
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000052.dart.weak.modular.expect
@@ -0,0 +1,10 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  function f() → Null {
+    core::print("hello");
+  }
+  f(){() →* Null};
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000053.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000053.dart.weak.modular.expect
new file mode 100644
index 0000000..f4841de
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000053.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  operator ==(dynamic other) → core::bool*
+    return throw "x";
+  method test() → dynamic {
+    super.{core::Object::==}(null);
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::C::•().{self::C::test}(){() →* dynamic};
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000067.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000067.dart.weak.modular.expect
new file mode 100644
index 0000000..66f50c0
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000067.dart.weak.modular.expect
@@ -0,0 +1,52 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+class A extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  constructor •() → self::A*
+    : super core::Object::•() {}
+  static factory foo() → self::A*
+    return self::C::bar();
+  method m() → core::int* {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::A {
+  static final field dynamic _redirecting# = <dynamic>[#C2];
+  constructor •() → self::C*
+    : super self::A::•() {}
+  static factory bar() → self::C*
+    return new self::D::•();
+  method m() → core::int* {
+    return 1;
+  }
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method m() → core::int* {
+    return 2;
+  }
+}
+static method main() → dynamic {
+  self::A* a = new self::D::•();
+  exp::Expect::equals(2, a.{self::A::m}(){() →* core::int*});
+}
+
+constants  {
+  #C1 = constructor-tearoff self::A::foo
+  #C2 = constructor-tearoff self::C::bar
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000068.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000068.dart.weak.modular.expect
new file mode 100644
index 0000000..9de7e9e
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000068.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+class G<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::G<self::G::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+static method main() → dynamic {
+  exp::Expect::isFalse(new self::G::•<self::B*>() is self::G<self::C*>*);
+  exp::Expect::isFalse(new self::G::•<self::A*>() is self::G<self::B*>*);
+  exp::Expect::isFalse(new self::G::•<self::A*>() is self::G<self::C*>*);
+  exp::Expect::isFalse(new self::G::•<core::Object*>() is self::G<self::B*>*);
+  exp::Expect::isFalse(new self::G::•<core::int*>() is self::G<self::B*>*);
+  exp::Expect::isFalse(new self::G::•<core::int*>() is self::G<core::double*>*);
+  exp::Expect::isFalse(new self::G::•<core::int*>() is self::G<core::String*>*);
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000069.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000069.dart.weak.modular.expect
new file mode 100644
index 0000000..07c2ec1
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000069.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  dynamic x;
+  core::int* i = 0;
+  while ((let final core::int* #t1 = i in let final core::int* #t2 = i = #t1.{core::num::+}(1){(core::num*) →* core::int*} in #t1).{core::num::<}(5){(core::num*) →* core::bool*}) {
+    core::int* x = i;
+  }
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000070.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000070.dart.weak.modular.expect
new file mode 100644
index 0000000..a5f9ac1
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000070.dart.weak.modular.expect
@@ -0,0 +1,77 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+class A<N extends core::Object* = dynamic, S extends core::Object* = dynamic, U extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  final field core::List<self::A::U*>* field;
+  constructor •(self::A::N* n, self::A::S* s) → self::A<self::A::N*, self::A::S*, self::A::U*>*
+    : self::A::field = <self::A::U*>[], super core::Object::•() {
+    exp::Expect::isTrue(n is self::A::N*);
+    exp::Expect::isTrue(s is self::A::S*);
+  }
+  constructor empty() → self::A<self::A::N*, self::A::S*, self::A::U*>*
+    : self::A::field = null, super core::Object::•() {}
+  const constructor c(self::A::U* u, self::A::S* s) → self::A<self::A::N*, self::A::S*, self::A::U*>*
+    : self::A::field = #C2, super core::Object::•()
+    ;
+  static factory f<N extends core::Object* = dynamic, S extends core::Object* = dynamic, U extends core::Object* = dynamic>(self::A::f::S* s) → self::A<self::A::f::N*, self::A::f::S*, self::A::f::U*>* {
+    exp::Expect::isTrue(s is self::A::f::S*);
+    return new self::A::empty<self::A::f::N*, self::A::f::S*, self::A::f::U*>();
+  }
+  get getter() → core::List<self::A::U*>* {
+    return this.{self::A::field}{core::List<self::A::U*>*};
+  }
+  set setter(covariant-by-class self::A::S* s) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class J<Aa extends core::Object* = dynamic, B extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::J<self::J::Aa*, self::J::B*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I<H extends core::Object* = dynamic, C extends core::Object* = dynamic, K extends core::Object* = dynamic> extends self::J<self::I::C*, self::I::K*> {
+  synthetic constructor •() → self::I<self::I::H*, self::I::C*, self::I::K*>*
+    : super self::J::•()
+    ;
+}
+static method main() → dynamic {
+  new self::A::•<core::num*, core::double*, core::List<dynamic>*>(1, 2.0);
+  self::A<dynamic, dynamic, dynamic>* a = self::A::f<core::int*, core::int*, core::int*>(1);
+  #C3;
+  core::List<dynamic>* z = a.{self::A::getter}{core::List<dynamic>*};
+  a.{self::A::setter} = 1;
+}
+
+constants  {
+  #C1 = null
+  #C2 = <Null>[#C1]
+  #C3 = self::A<core::int*, core::int*, core::List<dynamic>*> {field:#C2}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue_000070.dart:
+- A.c (from org-dartlang-testcase:///issue_000070.dart:22:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/rasta/issue_000080.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000080.dart.weak.modular.expect
new file mode 100644
index 0000000..e61a3ce
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000080.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Mixin extends core::Object {
+  field dynamic field = null;
+  synthetic constructor •() → self::Mixin*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic
+    return 87;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Foo&Object&Mixin = core::Object with self::Mixin /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_Foo&Object&Mixin*
+    : super core::Object::•()
+    ;
+  mixin-super-stub method foo() → dynamic
+    return super.{self::Mixin::foo}();
+  mixin-super-stub get field() → dynamic
+    return super.{self::Mixin::field};
+  mixin-super-stub set field(dynamic value) → void
+    return super.{self::Mixin::field} = value;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Foo extends self::_Foo&Object&Mixin {
+  synthetic constructor •() → self::Foo*
+    : super self::_Foo&Object&Mixin::•()
+    ;
+  method foo() → dynamic
+    return super.{self::_Foo&Object&Mixin::foo}();
+  method bar() → dynamic
+    return super.{self::_Foo&Object&Mixin::field};
+}
+static method main() → dynamic {
+  self::Foo* f = new self::Foo::•();
+  f.{self::_Foo&Object&Mixin::field} = 42;
+  core::print(f.{self::Foo::bar}(){() →* dynamic});
+}
diff --git a/pkg/front_end/testcases/rasta/issue_000081.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/issue_000081.dart.weak.modular.expect
new file mode 100644
index 0000000..5549963
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/issue_000081.dart.weak.modular.expect
@@ -0,0 +1,35 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Base extends core::Object {
+  field core::int* hashCode = 42;
+  synthetic constructor •() → self::Base*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Sub extends self::Base {
+  field core::int* _hashCode = null;
+  synthetic constructor •() → self::Sub*
+    : super self::Base::•()
+    ;
+  get hashCode() → core::int*
+    return let final core::int* #t1 = this.{self::Sub::_hashCode}{core::int*} in #t1 == null ?{core::int*} this.{self::Sub::_hashCode} = super.{self::Base::hashCode} : #t1;
+  method foo() → dynamic {
+    this.{self::Sub::_hashCode}{core::int*} == null ?{core::int*} this.{self::Sub::_hashCode} = super.{self::Base::hashCode} : null;
+  }
+}
+static method main() → dynamic {
+  core::print(new self::Sub::•().{self::Sub::hashCode}{core::int*});
+  core::List<Null>* l = <Null>[null];
+  let final core::List<Null>* #t2 = l in let final core::int* #t3 = 0 in #t2.{core::List::[]}(#t3){(core::int*) →* Null} == null ?{core::String*} #t2.{core::List::[]=}(#t3, "fisk" as{TypeError} Null){(core::int*, Null) →* void} : null;
+}
diff --git a/pkg/front_end/testcases/rasta/malformed_const_constructor.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/malformed_const_constructor.dart.weak.modular.expect
new file mode 100644
index 0000000..40bd823
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/malformed_const_constructor.dart.weak.modular.expect
@@ -0,0 +1,52 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/malformed_const_constructor.dart:8:5: Error: Expected '{' before this.
+//     : x = 'foo'
+//     ^
+//
+// pkg/front_end/testcases/rasta/malformed_const_constructor.dart:6:3: Error: A const constructor can't have a body.
+// Try removing either the 'const' keyword or the body.
+//   const A()
+//   ^^^^^
+//
+// pkg/front_end/testcases/rasta/malformed_const_constructor.dart:8:5: Error: Expected a class member, but got ':'.
+//     : x = 'foo'
+//     ^
+//
+// pkg/front_end/testcases/rasta/malformed_const_constructor.dart:8:7: Error: Variables must be declared using the keywords 'const', 'final', 'var' or a type name.
+// Try adding the name of the type of the variable or the keyword 'var'.
+//     : x = 'foo'
+//       ^
+//
+// pkg/front_end/testcases/rasta/malformed_const_constructor.dart:13:9: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+// Try using a constructor or factory that is 'const'.
+//   const A();
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::String* x = "foo";
+  constructor •() → self::A*
+    : self::A::x = "foo", super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/rasta/malformed_const_constructor.dart:13:9: Error: Cannot invoke a non-'const' constructor where a const expression is expected.
+Try using a constructor or factory that is 'const'.
+  const A();
+        ^";
+  new self::A::•();
+}
diff --git a/pkg/front_end/testcases/rasta/malformed_function.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/malformed_function.dart.weak.modular.expect
new file mode 100644
index 0000000..35bc1cd
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/malformed_function.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/malformed_function.dart:7:8: Error: Can't assign to a parenthesized expression.
+//   (null) = null;
+//        ^
+//
+import self as self;
+
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/rasta/malformed_function.dart:7:8: Error: Can't assign to a parenthesized expression.
+  (null) = null;
+       ^";
+}
diff --git a/pkg/front_end/testcases/rasta/malformed_function_type.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/malformed_function_type.dart.weak.modular.expect
new file mode 100644
index 0000000..50a886c
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/malformed_function_type.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/malformed_function_type.dart:5:16: Error: The typedef 'Handle' has a reference to itself.
+// typedef Handle Handle(String command);
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef Handle = invalid-type;
+static method main() → dynamic {
+  invalid-type h;
+}
diff --git a/pkg/front_end/testcases/rasta/mandatory_parameter_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/mandatory_parameter_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..ac6a230
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/mandatory_parameter_initializer.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/mandatory_parameter_initializer.dart:5:16: Error: Non-optional parameters can't have a default value.
+// Try removing the default value or making the parameter optional.
+// main(arguments = [x]) {
+//                ^
+//
+// pkg/front_end/testcases/rasta/mandatory_parameter_initializer.dart:5:18: Error: Constant expression expected.
+// Try inserting 'const'.
+// main(arguments = [x]) {
+//                  ^
+//
+// pkg/front_end/testcases/rasta/mandatory_parameter_initializer.dart:5:19: Error: Undefined name 'x'.
+// main(arguments = [x]) {
+//                   ^
+//
+// pkg/front_end/testcases/rasta/mandatory_parameter_initializer.dart:5:18: Error: Non-constant list literal is not a constant expression.
+// main(arguments = [x]) {
+//                  ^
+//
+import self as self;
+
+static method main(dynamic arguments = invalid-expression "Non-constant list literal is not a constant expression.") → dynamic {}
diff --git a/pkg/front_end/testcases/rasta/mixin_library.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/mixin_library.dart.weak.modular.expect
new file mode 100644
index 0000000..e6d1af6
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/mixin_library.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library test.mixin_library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/mixin_library.dart:16:18: Error: Superclass has no method named 'foo'.
+//   foo() => super.foo() + f();
+//                  ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Mixin<T extends core::Object* = dynamic> extends core::Object {
+  field dynamic x = self::f();
+  field dynamic y = null;
+  field dynamic z = null;
+  covariant-by-class field self::Mixin::T* t = null;
+  synthetic constructor •() → self::Mixin<self::Mixin::T*>*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic
+    return super.foo(){dynamic}.+(self::f());
+  method g(covariant-by-class self::Mixin::T* a) → self::Mixin::T*
+    return null;
+  method h() → dynamic
+    return self::V();
+  method l() → dynamic
+    return self::_private();
+  method _privateMethod() → dynamic
+    return 49;
+  method publicMethod() → dynamic
+    return this.{self::Mixin::_privateMethod}(){() →* dynamic};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f() → dynamic
+  return 2;
+static method V() → dynamic
+  return 87;
+static method _private() → dynamic
+  return 117;
+static method foo(dynamic m) → dynamic
+  return m{dynamic}._privateMethod();
diff --git a/pkg/front_end/testcases/rasta/native_is_illegal.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/native_is_illegal.dart.weak.modular.expect
new file mode 100644
index 0000000..7670aed
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/native_is_illegal.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Bar extends core::Object {
+  @#C2
+  external get x() → self::Bar*;
+  @#C4
+  external set x(self::Bar* value) → void;
+  @#C6
+  external method f() → dynamic;
+  @#C8
+  external static factory •() → self::Bar*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+@#C10
+external static method foo() → dynamic;
+
+constants  {
+  #C1 = "Bar_get_x"
+  #C2 = _in::ExternalName {name:#C1}
+  #C3 = "Bar_set_x"
+  #C4 = _in::ExternalName {name:#C3}
+  #C5 = "Bar_f"
+  #C6 = _in::ExternalName {name:#C5}
+  #C7 = "Bar_constructor"
+  #C8 = _in::ExternalName {name:#C7}
+  #C9 = "foo"
+  #C10 = _in::ExternalName {name:#C9}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///native_is_illegal.dart:
+- ExternalName. (from org-dartlang-sdk:///sdk/lib/internal/internal.dart:92:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/rasta/parser_error.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/parser_error.dart.weak.modular.expect
new file mode 100644
index 0000000..b83c501
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/parser_error.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/parser_error.dart:10:7: Error: Expected an identifier, but got '?'.
+// Try inserting an identifier before '?'.
+//   if (?b) return b;  /// 01: compile-time error
+//       ^
+//
+// pkg/front_end/testcases/rasta/parser_error.dart:10:9: Error: Expected ':' before this.
+//   if (?b) return b;  /// 01: compile-time error
+//         ^
+//
+// pkg/front_end/testcases/rasta/parser_error.dart:10:9: Error: Expected an identifier, but got ')'.
+// Try inserting an identifier before ')'.
+//   if (?b) return b;  /// 01: compile-time error
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static method test(dynamic a, {dynamic b = #C1, dynamic c = #C1}) → core::int* {
+  if(invalid-expression "pkg/front_end/testcases/rasta/parser_error.dart:10:7: Error: This couldn't be parsed.
+  if (?b) return b;  /// 01: compile-time error
+      ^" ?{invalid-type} b : invalid-expression "pkg/front_end/testcases/rasta/parser_error.dart:10:9: Error: This couldn't be parsed.
+  if (?b) return b;  /// 01: compile-time error
+        ^")
+    return b as{TypeError,ForDynamic} core::int*;
+  return a{dynamic}.+(b){dynamic}.+(c) as{TypeError,ForDynamic} core::int*;
+}
+static method main() → dynamic {
+  exp::Expect::equals(6, self::test(1, b: 2, c: 3));
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/rasta/previsit_deferred.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/previsit_deferred.dart.weak.modular.expect
new file mode 100644
index 0000000..0a16b0d
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/previsit_deferred.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library;
+import self as self;
+import "deferred_lib.dart" as def;
+
+import "org-dartlang-testcase:///deferred_lib.dart" deferred as lib;
+
+static method main() → dynamic {}
+static method test() → dynamic {
+  let final dynamic #t1 = CheckLibraryIsLoaded(lib) in def::foo();
+}
+
+library deferred_lib;
+import self as def;
+
+static method foo() → dynamic
+  return null;
diff --git a/pkg/front_end/testcases/rasta/static.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/static.dart.weak.modular.expect
new file mode 100644
index 0000000..3be7b62
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/static.dart.weak.modular.expect
@@ -0,0 +1,339 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/static.dart:28:9: Error: Getter not found: 'staticSetter'.
+//     Foo.staticSetter;
+//         ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:29:13: Error: Getter not found: 'staticSetter'.
+//     use(Foo.staticSetter);
+//             ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:31:9: Error: Setter not found: 'staticConstant'.
+//     Foo.staticConstant++;
+//         ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:32:13: Error: Setter not found: 'staticConstant'.
+//     use(Foo.staticConstant++);
+//             ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:35:9: Error: Setter not found: 'staticFunction'.
+//     Foo.staticFunction++;
+//         ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:36:13: Error: Setter not found: 'staticFunction'.
+//     use(Foo.staticFunction++);
+//             ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:37:9: Error: Setter not found: 'staticGetter'.
+//     Foo.staticGetter++;
+//         ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:38:13: Error: Setter not found: 'staticGetter'.
+//     use(Foo.staticGetter++);
+//             ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:39:9: Error: Getter not found: 'staticSetter'.
+//     Foo.staticSetter++;
+//         ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:40:13: Error: Getter not found: 'staticSetter'.
+//     use(Foo.staticSetter++);
+//             ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:42:11: Error: Setter not found: 'staticConstant'.
+//     ++Foo.staticConstant;
+//           ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:43:15: Error: Setter not found: 'staticConstant'.
+//     use(++Foo.staticConstant);
+//               ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:46:11: Error: Setter not found: 'staticFunction'.
+//     ++Foo.staticFunction;
+//           ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:47:15: Error: Setter not found: 'staticFunction'.
+//     use(++Foo.staticFunction);
+//               ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:48:11: Error: Setter not found: 'staticGetter'.
+//     ++Foo.staticGetter;
+//           ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:49:15: Error: Setter not found: 'staticGetter'.
+//     use(++Foo.staticGetter);
+//               ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:50:11: Error: Getter not found: 'staticSetter'.
+//     ++Foo.staticSetter;
+//           ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:51:15: Error: Getter not found: 'staticSetter'.
+//     use(++Foo.staticSetter);
+//               ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:61:9: Error: Getter not found: 'staticSetter'.
+//     Foo.staticSetter();
+//         ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:62:13: Error: Getter not found: 'staticSetter'.
+//     use(Foo.staticSetter());
+//             ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:64:9: Error: Setter not found: 'staticConstant'.
+//     Foo.staticConstant = 87;
+//         ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:65:13: Error: Setter not found: 'staticConstant'.
+//     use(Foo.staticConstant = 87);
+//             ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:68:9: Error: Setter not found: 'staticFunction'.
+//     Foo.staticFunction = 87;
+//         ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:69:13: Error: Setter not found: 'staticFunction'.
+//     use(Foo.staticFunction = 87);
+//             ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:70:9: Error: Setter not found: 'staticGetter'.
+//     Foo.staticGetter = 87;
+//         ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:71:13: Error: Setter not found: 'staticGetter'.
+//     use(Foo.staticGetter = 87);
+//             ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:75:9: Error: Setter not found: 'staticConstant'.
+//     Foo.staticConstant ??= 87;
+//         ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:76:13: Error: Setter not found: 'staticConstant'.
+//     use(Foo.staticConstant ??= 87);
+//             ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:79:9: Error: Setter not found: 'staticFunction'.
+//     Foo.staticFunction ??= 87;
+//         ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:80:13: Error: Setter not found: 'staticFunction'.
+//     use(Foo.staticFunction ??= 87);
+//             ^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:81:9: Error: Setter not found: 'staticGetter'.
+//     Foo.staticGetter ??= 87;
+//         ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:82:13: Error: Setter not found: 'staticGetter'.
+//     use(Foo.staticGetter ??= 87);
+//             ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:83:9: Error: Getter not found: 'staticSetter'.
+//     Foo.staticSetter ??= 87;
+//         ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:84:13: Error: Getter not found: 'staticSetter'.
+//     use(Foo.staticSetter ??= 87);
+//             ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/static.dart:53:23: Error: The method 'call' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing method, or defining a method named 'call'.
+//     Foo.staticConstant();
+//                       ^
+//
+// pkg/front_end/testcases/rasta/static.dart:54:27: Error: The method 'call' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing method, or defining a method named 'call'.
+//     use(Foo.staticConstant());
+//                           ^
+//
+// pkg/front_end/testcases/rasta/static.dart:55:20: Error: The method 'call' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing method, or defining a method named 'call'.
+//     Foo.staticField();
+//                    ^
+//
+// pkg/front_end/testcases/rasta/static.dart:56:24: Error: The method 'call' isn't defined for the class 'int'.
+// Try correcting the name to the name of an existing method, or defining a method named 'call'.
+//     use(Foo.staticField());
+//                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  static const field core::int* staticConstant = #C1;
+  static field core::int* staticField = 42;
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  static method staticFunction() → dynamic {}
+  static get staticGetter() → dynamic
+    return null;
+  static set staticSetter(dynamic _) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method use(dynamic x) → dynamic {
+  if(x =={core::Object::==}{(core::Object*) →* core::bool*} new core::DateTime::now().{core::DateTime::millisecondsSinceEpoch}{core::int*})
+    throw "Shouldn't happen";
+}
+static method main() → dynamic {
+  try {
+    #C1;
+    self::use(#C1);
+    self::Foo::staticField;
+    self::use(self::Foo::staticField);
+    #C2;
+    self::use(#C2);
+    self::Foo::staticGetter;
+    self::use(self::Foo::staticGetter);
+    invalid-expression "pkg/front_end/testcases/rasta/static.dart:28:9: Error: Getter not found: 'staticSetter'.
+    Foo.staticSetter;
+        ^^^^^^^^^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/static.dart:29:13: Error: Getter not found: 'staticSetter'.
+    use(Foo.staticSetter);
+            ^^^^^^^^^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/static.dart:31:9: Error: Setter not found: 'staticConstant'.
+    Foo.staticConstant++;
+        ^^^^^^^^^^^^^^";
+    self::use(let final core::int* #t1 = #C1 in let final invalid-type #t2 = invalid-expression "pkg/front_end/testcases/rasta/static.dart:32:13: Error: Setter not found: 'staticConstant'.
+    use(Foo.staticConstant++);
+            ^^^^^^^^^^^^^^" in #t1);
+    self::Foo::staticField = self::Foo::staticField.{core::num::+}(1){(core::num*) →* core::int*};
+    self::use(let final core::int* #t3 = self::Foo::staticField in let final core::int* #t4 = self::Foo::staticField = #t3.{core::num::+}(1){(core::num*) →* core::int*} in #t3);
+    invalid-expression "pkg/front_end/testcases/rasta/static.dart:35:9: Error: Setter not found: 'staticFunction'.
+    Foo.staticFunction++;
+        ^^^^^^^^^^^^^^";
+    self::use(let final () →* dynamic #t5 = #C2 in let final invalid-type #t6 = invalid-expression "pkg/front_end/testcases/rasta/static.dart:36:13: Error: Setter not found: 'staticFunction'.
+    use(Foo.staticFunction++);
+            ^^^^^^^^^^^^^^" in #t5);
+    invalid-expression "pkg/front_end/testcases/rasta/static.dart:37:9: Error: Setter not found: 'staticGetter'.
+    Foo.staticGetter++;
+        ^^^^^^^^^^^^";
+    self::use(let final dynamic #t7 = self::Foo::staticGetter in let final invalid-type #t8 = invalid-expression "pkg/front_end/testcases/rasta/static.dart:38:13: Error: Setter not found: 'staticGetter'.
+    use(Foo.staticGetter++);
+            ^^^^^^^^^^^^" in #t7);
+    self::Foo::staticSetter = invalid-expression "pkg/front_end/testcases/rasta/static.dart:39:9: Error: Getter not found: 'staticSetter'.
+    Foo.staticSetter++;
+        ^^^^^^^^^^^^"{<invalid>}.+(1);
+    self::use(let final invalid-type #t9 = invalid-expression "pkg/front_end/testcases/rasta/static.dart:40:13: Error: Getter not found: 'staticSetter'.
+    use(Foo.staticSetter++);
+            ^^^^^^^^^^^^" in let final invalid-type #t10 = self::Foo::staticSetter = #t9{<invalid>}.+(1) in #t9);
+    invalid-expression "pkg/front_end/testcases/rasta/static.dart:42:11: Error: Setter not found: 'staticConstant'.
+    ++Foo.staticConstant;
+          ^^^^^^^^^^^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/static.dart:43:15: Error: Setter not found: 'staticConstant'.
+    use(++Foo.staticConstant);
+              ^^^^^^^^^^^^^^");
+    self::Foo::staticField = self::Foo::staticField.{core::num::+}(1){(core::num*) →* core::int*};
+    self::use(self::Foo::staticField = self::Foo::staticField.{core::num::+}(1){(core::num*) →* core::int*});
+    invalid-expression "pkg/front_end/testcases/rasta/static.dart:46:11: Error: Setter not found: 'staticFunction'.
+    ++Foo.staticFunction;
+          ^^^^^^^^^^^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/static.dart:47:15: Error: Setter not found: 'staticFunction'.
+    use(++Foo.staticFunction);
+              ^^^^^^^^^^^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/static.dart:48:11: Error: Setter not found: 'staticGetter'.
+    ++Foo.staticGetter;
+          ^^^^^^^^^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/static.dart:49:15: Error: Setter not found: 'staticGetter'.
+    use(++Foo.staticGetter);
+              ^^^^^^^^^^^^");
+    self::Foo::staticSetter = invalid-expression "pkg/front_end/testcases/rasta/static.dart:50:11: Error: Getter not found: 'staticSetter'.
+    ++Foo.staticSetter;
+          ^^^^^^^^^^^^"{<invalid>}.+(1);
+    self::use(self::Foo::staticSetter = invalid-expression "pkg/front_end/testcases/rasta/static.dart:51:15: Error: Getter not found: 'staticSetter'.
+    use(++Foo.staticSetter);
+              ^^^^^^^^^^^^"{<invalid>}.+(1));
+    invalid-expression "pkg/front_end/testcases/rasta/static.dart:53:23: Error: The method 'call' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing method, or defining a method named 'call'.
+    Foo.staticConstant();
+                      ^" in #C1{<unresolved>}.call();
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/static.dart:54:27: Error: The method 'call' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing method, or defining a method named 'call'.
+    use(Foo.staticConstant());
+                          ^" in #C1{<unresolved>}.call());
+    invalid-expression "pkg/front_end/testcases/rasta/static.dart:55:20: Error: The method 'call' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing method, or defining a method named 'call'.
+    Foo.staticField();
+                   ^" in self::Foo::staticField{<unresolved>}.call();
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/static.dart:56:24: Error: The method 'call' isn't defined for the class 'int'.
+Try correcting the name to the name of an existing method, or defining a method named 'call'.
+    use(Foo.staticField());
+                       ^" in self::Foo::staticField{<unresolved>}.call());
+    self::Foo::staticFunction();
+    self::use(self::Foo::staticFunction());
+    self::Foo::staticGetter{dynamic}.call();
+    self::use(self::Foo::staticGetter{dynamic}.call());
+    invalid-expression "pkg/front_end/testcases/rasta/static.dart:61:9: Error: Getter not found: 'staticSetter'.
+    Foo.staticSetter();
+        ^^^^^^^^^^^^"{dynamic}.call();
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/static.dart:62:13: Error: Getter not found: 'staticSetter'.
+    use(Foo.staticSetter());
+            ^^^^^^^^^^^^"{dynamic}.call());
+    invalid-expression "pkg/front_end/testcases/rasta/static.dart:64:9: Error: Setter not found: 'staticConstant'.
+    Foo.staticConstant = 87;
+        ^^^^^^^^^^^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/static.dart:65:13: Error: Setter not found: 'staticConstant'.
+    use(Foo.staticConstant = 87);
+            ^^^^^^^^^^^^^^");
+    self::Foo::staticField = 87;
+    self::use(self::Foo::staticField = 87);
+    invalid-expression "pkg/front_end/testcases/rasta/static.dart:68:9: Error: Setter not found: 'staticFunction'.
+    Foo.staticFunction = 87;
+        ^^^^^^^^^^^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/static.dart:69:13: Error: Setter not found: 'staticFunction'.
+    use(Foo.staticFunction = 87);
+            ^^^^^^^^^^^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/static.dart:70:9: Error: Setter not found: 'staticGetter'.
+    Foo.staticGetter = 87;
+        ^^^^^^^^^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/static.dart:71:13: Error: Setter not found: 'staticGetter'.
+    use(Foo.staticGetter = 87);
+            ^^^^^^^^^^^^");
+    self::Foo::staticSetter = 87;
+    self::use(self::Foo::staticSetter = 87);
+    #C1 == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/rasta/static.dart:75:9: Error: Setter not found: 'staticConstant'.
+    Foo.staticConstant ??= 87;
+        ^^^^^^^^^^^^^^" : null;
+    self::use(let final core::int* #t11 = #C1 in #t11 == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/rasta/static.dart:76:13: Error: Setter not found: 'staticConstant'.
+    use(Foo.staticConstant ??= 87);
+            ^^^^^^^^^^^^^^" : #t11);
+    self::Foo::staticField == null ?{core::int*} self::Foo::staticField = 87 : null;
+    self::use(let final core::int* #t12 = self::Foo::staticField in #t12 == null ?{core::int*} self::Foo::staticField = 87 : #t12);
+    #C2 == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/rasta/static.dart:79:9: Error: Setter not found: 'staticFunction'.
+    Foo.staticFunction ??= 87;
+        ^^^^^^^^^^^^^^" : null;
+    self::use(let final () →* dynamic #t13 = #C2 in #t13 == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/rasta/static.dart:80:13: Error: Setter not found: 'staticFunction'.
+    use(Foo.staticFunction ??= 87);
+            ^^^^^^^^^^^^^^" : #t13);
+    self::Foo::staticGetter == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/rasta/static.dart:81:9: Error: Setter not found: 'staticGetter'.
+    Foo.staticGetter ??= 87;
+        ^^^^^^^^^^^^" : null;
+    self::use(let final dynamic #t14 = self::Foo::staticGetter in #t14 == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/rasta/static.dart:82:13: Error: Setter not found: 'staticGetter'.
+    use(Foo.staticGetter ??= 87);
+            ^^^^^^^^^^^^" : #t14);
+    invalid-expression "pkg/front_end/testcases/rasta/static.dart:83:9: Error: Getter not found: 'staticSetter'.
+    Foo.staticSetter ??= 87;
+        ^^^^^^^^^^^^" == null ?{invalid-type} self::Foo::staticSetter = 87 : null;
+    self::use(let final invalid-type #t15 = invalid-expression "pkg/front_end/testcases/rasta/static.dart:84:13: Error: Getter not found: 'staticSetter'.
+    use(Foo.staticSetter ??= 87);
+            ^^^^^^^^^^^^" in #t15 == null ?{invalid-type} self::Foo::staticSetter = 87 : #t15);
+  }
+  on core::NoSuchMethodError* catch(no-exception-var) {
+  }
+}
+
+constants  {
+  #C1 = 42
+  #C2 = static-tearoff self::Foo::staticFunction
+}
diff --git a/pkg/front_end/testcases/rasta/super.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/super.dart.weak.modular.expect
new file mode 100644
index 0000000..e24c07d
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/super.dart.weak.modular.expect
@@ -0,0 +1,687 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/super.dart:27:7: Error: 'n' is already declared in this scope.
+//   set n(_) {}
+//       ^
+// pkg/front_end/testcases/rasta/super.dart:26:8: Context: Previous declaration of 'n'.
+//   void n() {}
+//        ^
+//
+// pkg/front_end/testcases/rasta/super.dart:43:5: Error: '+' is not a prefix operator.
+// Try removing '+'.
+//     +super;
+//     ^
+//
+// pkg/front_end/testcases/rasta/super.dart:43:6: Error: Can't use 'super' as an expression.
+// To delegate a constructor to a super constructor, put the super call as an initializer.
+//     +super;
+//      ^^^^^
+//
+// pkg/front_end/testcases/rasta/super.dart:44:9: Error: '+' is not a prefix operator.
+// Try removing '+'.
+//     use(+super);
+//         ^
+//
+// pkg/front_end/testcases/rasta/super.dart:44:10: Error: Can't use 'super' as an expression.
+// To delegate a constructor to a super constructor, put the super call as an initializer.
+//     use(+super);
+//          ^^^^^
+//
+// pkg/front_end/testcases/rasta/super.dart:62:11: Error: Superclass has no getter named 'g'.
+//     super.g;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:63:15: Error: Superclass has no getter named 'g'.
+//     use(super.g);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:83:11: Error: Superclass has no setter named 'e'.
+//     super.e++;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:84:15: Error: Superclass has no setter named 'e'.
+//     use(super.e++);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:85:11: Error: Superclass has no setter named 'f'.
+//     super.f++;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:86:15: Error: Superclass has no setter named 'f'.
+//     use(super.f++);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:87:11: Error: Superclass has no getter named 'g'.
+//     super.g++;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:88:15: Error: Superclass has no getter named 'g'.
+//     use(super.g++);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:95:11: Error: Superclass has no setter named 'm'.
+//     super.m++;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:96:15: Error: Superclass has no setter named 'm'.
+//     use(super.m++);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:108:13: Error: Superclass has no setter named 'e'.
+//     ++super.e;
+//             ^
+//
+// pkg/front_end/testcases/rasta/super.dart:109:17: Error: Superclass has no setter named 'e'.
+//     use(++super.e);
+//                 ^
+//
+// pkg/front_end/testcases/rasta/super.dart:110:13: Error: Superclass has no setter named 'f'.
+//     ++super.f;
+//             ^
+//
+// pkg/front_end/testcases/rasta/super.dart:111:17: Error: Superclass has no setter named 'f'.
+//     use(++super.f);
+//                 ^
+//
+// pkg/front_end/testcases/rasta/super.dart:112:13: Error: Superclass has no getter named 'g'.
+//     ++super.g;
+//             ^
+//
+// pkg/front_end/testcases/rasta/super.dart:113:17: Error: Superclass has no getter named 'g'.
+//     use(++super.g);
+//                 ^
+//
+// pkg/front_end/testcases/rasta/super.dart:120:13: Error: Superclass has no setter named 'm'.
+//     ++super.m;
+//             ^
+//
+// pkg/front_end/testcases/rasta/super.dart:121:17: Error: Superclass has no setter named 'm'.
+//     use(++super.m);
+//                 ^
+//
+// pkg/front_end/testcases/rasta/super.dart:137:11: Error: Superclass has no method named 'g'.
+//     super.g();
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:138:15: Error: Superclass has no method named 'g'.
+//     use(super.g());
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:160:11: Error: Superclass has no setter named 'e'.
+//     super.e = 42;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:161:15: Error: Superclass has no setter named 'e'.
+//     use(super.e = 42);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:162:11: Error: Superclass has no setter named 'f'.
+//     super.f = 42;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:163:15: Error: Superclass has no setter named 'f'.
+//     use(super.f = 42);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:172:11: Error: Superclass has no setter named 'm'.
+//     super.m = 42;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:173:15: Error: Superclass has no setter named 'm'.
+//     use(super.m = 42);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:185:11: Error: Superclass has no setter named 'e'.
+//     super.e ??= 42;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:186:15: Error: Superclass has no setter named 'e'.
+//     use(super.e ??= 42);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:187:11: Error: Superclass has no setter named 'f'.
+//     super.f ??= 42;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:188:15: Error: Superclass has no setter named 'f'.
+//     use(super.f ??= 42);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:189:11: Error: Superclass has no getter named 'g'.
+//     super.g ??= 42;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:190:15: Error: Superclass has no getter named 'g'.
+//     use(super.g ??= 42);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:197:11: Error: Superclass has no setter named 'm'.
+//     super.m ??= 42;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:198:15: Error: Superclass has no setter named 'm'.
+//     use(super.m ??= 42);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:210:11: Error: Superclass has no setter named 'e'.
+//     super.e += 42;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:211:15: Error: Superclass has no setter named 'e'.
+//     use(super.e += 42);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:212:11: Error: Superclass has no setter named 'f'.
+//     super.f += 42;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:213:15: Error: Superclass has no setter named 'f'.
+//     use(super.f += 42);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:214:11: Error: Superclass has no getter named 'g'.
+//     super.g += 42;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:215:15: Error: Superclass has no getter named 'g'.
+//     use(super.g += 42);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:222:11: Error: Superclass has no setter named 'm'.
+//     super.m += 42;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:223:15: Error: Superclass has no setter named 'm'.
+//     use(super.m += 42);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:235:11: Error: Superclass has no setter named 'e'.
+//     super.e -= 42;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:236:15: Error: Superclass has no setter named 'e'.
+//     use(super.e -= 42);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:237:11: Error: Superclass has no setter named 'f'.
+//     super.f -= 42;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:238:15: Error: Superclass has no setter named 'f'.
+//     use(super.f -= 42);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:239:11: Error: Superclass has no getter named 'g'.
+//     super.g -= 42;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:240:15: Error: Superclass has no getter named 'g'.
+//     use(super.g -= 42);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:247:11: Error: Superclass has no setter named 'm'.
+//     super.m -= 42;
+//           ^
+//
+// pkg/front_end/testcases/rasta/super.dart:248:15: Error: Superclass has no setter named 'm'.
+//     use(super.m -= 42);
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:95:12: Error: The operator '+' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//     super.m++;
+//            ^
+//
+// pkg/front_end/testcases/rasta/super.dart:96:16: Error: The operator '+' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//     use(super.m++);
+//                ^
+//
+// pkg/front_end/testcases/rasta/super.dart:97:12: Error: The operator '+' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//     super.n++;
+//            ^
+//
+// pkg/front_end/testcases/rasta/super.dart:98:16: Error: The operator '+' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//     use(super.n++);
+//                ^
+//
+// pkg/front_end/testcases/rasta/super.dart:120:5: Error: The operator '+' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//     ++super.m;
+//     ^
+//
+// pkg/front_end/testcases/rasta/super.dart:121:9: Error: The operator '+' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//     use(++super.m);
+//         ^
+//
+// pkg/front_end/testcases/rasta/super.dart:122:5: Error: The operator '+' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//     ++super.n;
+//     ^
+//
+// pkg/front_end/testcases/rasta/super.dart:123:9: Error: The operator '+' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//     use(++super.n);
+//         ^
+//
+// pkg/front_end/testcases/rasta/super.dart:146:15: Error: This expression has type 'void' and can't be used.
+//     use(super.m());
+//               ^
+//
+// pkg/front_end/testcases/rasta/super.dart:147:12: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//     super.m(87);
+//            ^
+//
+// pkg/front_end/testcases/rasta/super.dart:148:16: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//     use(super.m(87));
+//                ^
+//
+// pkg/front_end/testcases/rasta/super.dart:149:12: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//     super.n(87);
+//            ^
+//
+// pkg/front_end/testcases/rasta/super.dart:150:16: Error: Too many positional arguments: 0 allowed, but 1 found.
+// Try removing the extra positional arguments.
+//     use(super.n(87));
+//                ^
+//
+// pkg/front_end/testcases/rasta/super.dart:222:13: Error: The operator '+' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//     super.m += 42;
+//             ^
+//
+// pkg/front_end/testcases/rasta/super.dart:223:17: Error: The operator '+' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//     use(super.m += 42);
+//                 ^
+//
+// pkg/front_end/testcases/rasta/super.dart:224:13: Error: The operator '+' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//     super.n += 42;
+//             ^
+//
+// pkg/front_end/testcases/rasta/super.dart:225:17: Error: The operator '+' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '+' operator.
+//     use(super.n += 42);
+//                 ^
+//
+// pkg/front_end/testcases/rasta/super.dart:247:13: Error: The operator '-' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '-' operator.
+//     super.m -= 42;
+//             ^
+//
+// pkg/front_end/testcases/rasta/super.dart:248:17: Error: The operator '-' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '-' operator.
+//     use(super.m -= 42);
+//                 ^
+//
+// pkg/front_end/testcases/rasta/super.dart:249:13: Error: The operator '-' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '-' operator.
+//     super.n -= 42;
+//             ^
+//
+// pkg/front_end/testcases/rasta/super.dart:250:17: Error: The operator '-' isn't defined for the class 'void Function()'.
+// Try correcting the operator to an existing operator, or defining a '-' operator.
+//     use(super.n -= 42);
+//                 ^
+//
+// pkg/front_end/testcases/rasta/super.dart:11:9: Error: Final field 'f' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final f;
+//         ^
+//
+// pkg/front_end/testcases/rasta/super.dart:33:9: Error: Final field 'd' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final d;
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field dynamic a = null;
+  field dynamic b = null;
+  field dynamic c = null;
+  field dynamic d = null;
+  final field dynamic f = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  get e() → dynamic
+    return null;
+  set g(dynamic _) → void {}
+  get h() → dynamic
+    return null;
+  set h(dynamic _) → void {}
+  get i() → dynamic
+    return null;
+  operator [](dynamic _) → dynamic
+    return null;
+  operator []=(dynamic a, dynamic b) → void {}
+  operator ~() → dynamic
+    return 117;
+  operator unary-() → dynamic
+    return 117;
+  operator ==(dynamic other) → core::bool*
+    return true;
+  method m() → void {}
+  method n() → void {}
+  set n(dynamic _) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  final field dynamic d = null;
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  get b() → dynamic
+    return null;
+  set c(dynamic x) → void {}
+  set i(dynamic x) → void {}
+}
+class C extends self::B {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  method test() → dynamic {
+    super.{self::A::~}();
+    self::use(super.{self::A::~}());
+    super.{self::A::unary-}();
+    self::use(super.{self::A::unary-}());
+    invalid-expression "pkg/front_end/testcases/rasta/super.dart:43:5: Error: This couldn't be parsed.
+    +super;
+    ^"{<invalid>}.+(invalid-expression "pkg/front_end/testcases/rasta/super.dart:43:6: Error: Can't use 'super' as an expression.
+To delegate a constructor to a super constructor, put the super call as an initializer.
+    +super;
+     ^^^^^");
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/super.dart:44:9: Error: This couldn't be parsed.
+    use(+super);
+        ^"{<invalid>}.+(invalid-expression "pkg/front_end/testcases/rasta/super.dart:44:10: Error: Can't use 'super' as an expression.
+To delegate a constructor to a super constructor, put the super call as an initializer.
+    use(+super);
+         ^^^^^"));
+    super.{self::A::==}(87);
+    self::use(super.{self::A::==}(87));
+    !super.{self::A::==}(87);
+    self::use(!super.{self::A::==}(87));
+    super.{self::A::a};
+    self::use(super.{self::A::a});
+    super.{self::B::b};
+    self::use(super.{self::B::b});
+    super.{self::A::c};
+    self::use(super.{self::A::c});
+    super.{self::B::d};
+    self::use(super.{self::B::d});
+    super.{self::A::e};
+    self::use(super.{self::A::e});
+    super.{self::A::f};
+    self::use(super.{self::A::f});
+    super.g;
+    self::use(super.g);
+    super.{self::A::h};
+    self::use(super.{self::A::h});
+    super.{self::A::i};
+    self::use(super.{self::A::i});
+    super.{self::A::[]}(87);
+    self::use(super.{self::A::[]}(87));
+    super.{self::A::m};
+    self::use(super.{self::A::m});
+    super.{self::A::n};
+    self::use(super.{self::A::n});
+    super.{self::A::a} = super.{self::A::a}{dynamic}.+(1);
+    self::use(let final dynamic #t1 = super.{self::A::a} in let final dynamic #t2 = super.{self::A::a} = #t1{dynamic}.+(1) in #t1);
+    super.{self::A::b} = super.{self::B::b}{dynamic}.+(1);
+    self::use(let final dynamic #t3 = super.{self::B::b} in let final dynamic #t4 = super.{self::A::b} = #t3{dynamic}.+(1) in #t3);
+    super.{self::B::c} = super.{self::A::c}{dynamic}.+(1);
+    self::use(let final dynamic #t5 = super.{self::A::c} in let final dynamic #t6 = super.{self::B::c} = #t5{dynamic}.+(1) in #t5);
+    super.{self::A::d} = super.{self::B::d}{dynamic}.+(1);
+    self::use(let final dynamic #t7 = super.{self::B::d} in let final dynamic #t8 = super.{self::A::d} = #t7{dynamic}.+(1) in #t7);
+    super.e = super.{self::A::e}{dynamic}.+(1);
+    self::use(let final dynamic #t9 = super.{self::A::e} in let final dynamic #t10 = super.e = #t9{dynamic}.+(1) in #t9);
+    super.f = super.{self::A::f}{dynamic}.+(1);
+    self::use(let final dynamic #t11 = super.{self::A::f} in let final dynamic #t12 = super.f = #t11{dynamic}.+(1) in #t11);
+    super.{self::A::g} = super.g{dynamic}.+(1);
+    self::use(let final dynamic #t13 = super.g in let final dynamic #t14 = super.{self::A::g} = #t13{dynamic}.+(1) in #t13);
+    super.{self::A::h} = super.{self::A::h}{dynamic}.+(1);
+    self::use(let final dynamic #t15 = super.{self::A::h} in let final dynamic #t16 = super.{self::A::h} = #t15{dynamic}.+(1) in #t15);
+    super.{self::B::i} = super.{self::A::i}{dynamic}.+(1);
+    self::use(let final dynamic #t17 = super.{self::A::i} in let final dynamic #t18 = super.{self::B::i} = #t17{dynamic}.+(1) in #t17);
+    let final core::int* #t19 = 87 in super.{self::A::[]=}(#t19, super.{self::A::[]}(#t19){dynamic}.+(1));
+    self::use(let final core::int* #t20 = 87 in let final dynamic #t21 = super.{self::A::[]}(#t20) in let final void #t22 = super.{self::A::[]=}(#t20, #t21{dynamic}.+(1)) in #t21);
+    super.m = invalid-expression "pkg/front_end/testcases/rasta/super.dart:95:12: Error: The operator '+' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+    super.m++;
+           ^" in super.{self::A::m}{<unresolved>}.+(1);
+    self::use(let final () →* void #t23 = super.{self::A::m} in let final dynamic #t24 = super.m = invalid-expression "pkg/front_end/testcases/rasta/super.dart:96:16: Error: The operator '+' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+    use(super.m++);
+               ^" in #t23{<unresolved>}.+(1) in #t23);
+    super.{self::A::n} = invalid-expression "pkg/front_end/testcases/rasta/super.dart:97:12: Error: The operator '+' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+    super.n++;
+           ^" in super.{self::A::n}{<unresolved>}.+(1);
+    self::use(let final () →* void #t25 = super.{self::A::n} in let final dynamic #t26 = super.{self::A::n} = invalid-expression "pkg/front_end/testcases/rasta/super.dart:98:16: Error: The operator '+' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+    use(super.n++);
+               ^" in #t25{<unresolved>}.+(1) in #t25);
+    super.{self::A::a} = super.{self::A::a}{dynamic}.+(1);
+    self::use(super.{self::A::a} = super.{self::A::a}{dynamic}.+(1));
+    super.{self::A::b} = super.{self::B::b}{dynamic}.+(1);
+    self::use(super.{self::A::b} = super.{self::B::b}{dynamic}.+(1));
+    super.{self::B::c} = super.{self::A::c}{dynamic}.+(1);
+    self::use(super.{self::B::c} = super.{self::A::c}{dynamic}.+(1));
+    super.{self::A::d} = super.{self::B::d}{dynamic}.+(1);
+    self::use(super.{self::A::d} = super.{self::B::d}{dynamic}.+(1));
+    super.e = super.{self::A::e}{dynamic}.+(1);
+    self::use(super.e = super.{self::A::e}{dynamic}.+(1));
+    super.f = super.{self::A::f}{dynamic}.+(1);
+    self::use(super.f = super.{self::A::f}{dynamic}.+(1));
+    super.{self::A::g} = super.g{dynamic}.+(1);
+    self::use(super.{self::A::g} = super.g{dynamic}.+(1));
+    super.{self::A::h} = super.{self::A::h}{dynamic}.+(1);
+    self::use(super.{self::A::h} = super.{self::A::h}{dynamic}.+(1));
+    super.{self::B::i} = super.{self::A::i}{dynamic}.+(1);
+    self::use(super.{self::B::i} = super.{self::A::i}{dynamic}.+(1));
+    let final core::int* #t27 = 87 in let final dynamic #t28 = super.{self::A::[]}(#t27){dynamic}.+(1) in let final void #t29 = super.{self::A::[]=}(#t27, #t28) in #t28;
+    self::use(let final core::int* #t30 = 87 in let final dynamic #t31 = super.{self::A::[]}(#t30){dynamic}.+(1) in let final void #t32 = super.{self::A::[]=}(#t30, #t31) in #t31);
+    super.m = invalid-expression "pkg/front_end/testcases/rasta/super.dart:120:5: Error: The operator '+' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+    ++super.m;
+    ^" in super.{self::A::m}{<unresolved>}.+(1);
+    self::use(super.m = invalid-expression "pkg/front_end/testcases/rasta/super.dart:121:9: Error: The operator '+' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+    use(++super.m);
+        ^" in super.{self::A::m}{<unresolved>}.+(1));
+    super.{self::A::n} = invalid-expression "pkg/front_end/testcases/rasta/super.dart:122:5: Error: The operator '+' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+    ++super.n;
+    ^" in super.{self::A::n}{<unresolved>}.+(1);
+    self::use(super.{self::A::n} = invalid-expression "pkg/front_end/testcases/rasta/super.dart:123:9: Error: The operator '+' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+    use(++super.n);
+        ^" in super.{self::A::n}{<unresolved>}.+(1));
+    super.{self::A::a}{dynamic}.call();
+    self::use(super.{self::A::a}{dynamic}.call());
+    super.{self::B::b}{dynamic}.call();
+    self::use(super.{self::B::b}{dynamic}.call());
+    super.{self::A::c}{dynamic}.call();
+    self::use(super.{self::A::c}{dynamic}.call());
+    super.{self::B::d}{dynamic}.call();
+    self::use(super.{self::B::d}{dynamic}.call());
+    super.{self::A::e}{dynamic}.call();
+    self::use(super.{self::A::e}{dynamic}.call());
+    super.{self::A::f}{dynamic}.call();
+    self::use(super.{self::A::f}{dynamic}.call());
+    super.g();
+    self::use(super.g());
+    super.{self::A::h}{dynamic}.call();
+    self::use(super.{self::A::h}{dynamic}.call());
+    super.{self::A::i}{dynamic}.call();
+    self::use(super.{self::A::i}{dynamic}.call());
+    super.{self::A::[]}(87){dynamic}.call();
+    self::use(super.{self::A::[]}(87){dynamic}.call());
+    super.{self::A::m}();
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/super.dart:146:15: Error: This expression has type 'void' and can't be used.
+    use(super.m());
+              ^" in super.{self::A::m}());
+    invalid-expression "pkg/front_end/testcases/rasta/super.dart:147:12: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+    super.m(87);
+           ^" in super.{self::A::m}(87);
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/super.dart:148:16: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+    use(super.m(87));
+               ^" in super.{self::A::m}(87));
+    invalid-expression "pkg/front_end/testcases/rasta/super.dart:149:12: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+    super.n(87);
+           ^" in super.{self::A::n}(87);
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/super.dart:150:16: Error: Too many positional arguments: 0 allowed, but 1 found.
+Try removing the extra positional arguments.
+    use(super.n(87));
+               ^" in super.{self::A::n}(87));
+    super.{self::A::a} = 42;
+    self::use(super.{self::A::a} = 42);
+    super.{self::A::b} = 42;
+    self::use(super.{self::A::b} = 42);
+    super.{self::B::c} = 42;
+    self::use(super.{self::B::c} = 42);
+    super.{self::A::d} = 42;
+    self::use(super.{self::A::d} = 42);
+    super.e = 42;
+    self::use(super.e = 42);
+    super.f = 42;
+    self::use(super.f = 42);
+    super.{self::A::g} = 42;
+    self::use(super.{self::A::g} = 42);
+    super.{self::A::h} = 42;
+    self::use(super.{self::A::h} = 42);
+    super.{self::B::i} = 42;
+    self::use(super.{self::B::i} = 42);
+    super.{self::A::[]=}(87, 42);
+    self::use(let final core::int* #t33 = 87 in let final core::int* #t34 = 42 in let final void #t35 = super.{self::A::[]=}(#t33, #t34) in #t34);
+    super.m = 42;
+    self::use(super.m = 42);
+    super.{self::A::n} = 42;
+    self::use(super.{self::A::n} = 42);
+    super.{self::A::a} == null ?{dynamic} super.{self::A::a} = 42 : null;
+    self::use(let final dynamic #t36 = super.{self::A::a} in #t36 == null ?{dynamic} super.{self::A::a} = 42 : #t36);
+    super.{self::B::b} == null ?{dynamic} super.{self::A::b} = 42 : null;
+    self::use(let final dynamic #t37 = super.{self::B::b} in #t37 == null ?{dynamic} super.{self::A::b} = 42 : #t37);
+    super.{self::A::c} == null ?{dynamic} super.{self::B::c} = 42 : null;
+    self::use(let final dynamic #t38 = super.{self::A::c} in #t38 == null ?{dynamic} super.{self::B::c} = 42 : #t38);
+    super.{self::B::d} == null ?{dynamic} super.{self::A::d} = 42 : null;
+    self::use(let final dynamic #t39 = super.{self::B::d} in #t39 == null ?{dynamic} super.{self::A::d} = 42 : #t39);
+    super.{self::A::e} == null ?{dynamic} super.e = 42 : null;
+    self::use(let final dynamic #t40 = super.{self::A::e} in #t40 == null ?{dynamic} super.e = 42 : #t40);
+    super.{self::A::f} == null ?{dynamic} super.f = 42 : null;
+    self::use(let final dynamic #t41 = super.{self::A::f} in #t41 == null ?{dynamic} super.f = 42 : #t41);
+    super.g == null ?{dynamic} super.{self::A::g} = 42 : null;
+    self::use(let final dynamic #t42 = super.g in #t42 == null ?{dynamic} super.{self::A::g} = 42 : #t42);
+    super.{self::A::h} == null ?{dynamic} super.{self::A::h} = 42 : null;
+    self::use(let final dynamic #t43 = super.{self::A::h} in #t43 == null ?{dynamic} super.{self::A::h} = 42 : #t43);
+    super.{self::A::i} == null ?{dynamic} super.{self::B::i} = 42 : null;
+    self::use(let final dynamic #t44 = super.{self::A::i} in #t44 == null ?{dynamic} super.{self::B::i} = 42 : #t44);
+    let final core::int* #t45 = 87 in super.{self::A::[]}(#t45) == null ?{dynamic} super.{self::A::[]=}(#t45, 42) : null;
+    self::use(let final core::int* #t46 = 87 in let final dynamic #t47 = super.{self::A::[]}(#t46) in #t47 == null ?{dynamic} let final core::int* #t48 = 42 in let final void #t49 = super.{self::A::[]=}(#t46, #t48) in #t48 : #t47);
+    super.{self::A::m} == null ?{core::Object*} super.m = 42 : null;
+    self::use(let final () →* void #t50 = super.{self::A::m} in #t50 == null ?{core::Object*} super.m = 42 : #t50);
+    super.{self::A::n} == null ?{core::Object*} super.{self::A::n} = 42 : null;
+    self::use(let final () →* void #t51 = super.{self::A::n} in #t51 == null ?{core::Object*} super.{self::A::n} = 42 : #t51);
+    super.{self::A::a} = super.{self::A::a}{dynamic}.+(42);
+    self::use(super.{self::A::a} = super.{self::A::a}{dynamic}.+(42));
+    super.{self::A::b} = super.{self::B::b}{dynamic}.+(42);
+    self::use(super.{self::A::b} = super.{self::B::b}{dynamic}.+(42));
+    super.{self::B::c} = super.{self::A::c}{dynamic}.+(42);
+    self::use(super.{self::B::c} = super.{self::A::c}{dynamic}.+(42));
+    super.{self::A::d} = super.{self::B::d}{dynamic}.+(42);
+    self::use(super.{self::A::d} = super.{self::B::d}{dynamic}.+(42));
+    super.e = super.{self::A::e}{dynamic}.+(42);
+    self::use(super.e = super.{self::A::e}{dynamic}.+(42));
+    super.f = super.{self::A::f}{dynamic}.+(42);
+    self::use(super.f = super.{self::A::f}{dynamic}.+(42));
+    super.{self::A::g} = super.g{dynamic}.+(42);
+    self::use(super.{self::A::g} = super.g{dynamic}.+(42));
+    super.{self::A::h} = super.{self::A::h}{dynamic}.+(42);
+    self::use(super.{self::A::h} = super.{self::A::h}{dynamic}.+(42));
+    super.{self::B::i} = super.{self::A::i}{dynamic}.+(42);
+    self::use(super.{self::B::i} = super.{self::A::i}{dynamic}.+(42));
+    let final core::int* #t52 = 87 in super.{self::A::[]=}(#t52, super.{self::A::[]}(#t52){dynamic}.+(42));
+    self::use(let final core::int* #t53 = 87 in let final dynamic #t54 = super.{self::A::[]}(#t53){dynamic}.+(42) in let final void #t55 = super.{self::A::[]=}(#t53, #t54) in #t54);
+    super.m = invalid-expression "pkg/front_end/testcases/rasta/super.dart:222:13: Error: The operator '+' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+    super.m += 42;
+            ^" in super.{self::A::m}{<unresolved>}.+(42);
+    self::use(super.m = invalid-expression "pkg/front_end/testcases/rasta/super.dart:223:17: Error: The operator '+' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+    use(super.m += 42);
+                ^" in super.{self::A::m}{<unresolved>}.+(42));
+    super.{self::A::n} = invalid-expression "pkg/front_end/testcases/rasta/super.dart:224:13: Error: The operator '+' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+    super.n += 42;
+            ^" in super.{self::A::n}{<unresolved>}.+(42);
+    self::use(super.{self::A::n} = invalid-expression "pkg/front_end/testcases/rasta/super.dart:225:17: Error: The operator '+' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '+' operator.
+    use(super.n += 42);
+                ^" in super.{self::A::n}{<unresolved>}.+(42));
+    super.{self::A::a} = super.{self::A::a}{dynamic}.-(42);
+    self::use(super.{self::A::a} = super.{self::A::a}{dynamic}.-(42));
+    super.{self::A::b} = super.{self::B::b}{dynamic}.-(42);
+    self::use(super.{self::A::b} = super.{self::B::b}{dynamic}.-(42));
+    super.{self::B::c} = super.{self::A::c}{dynamic}.-(42);
+    self::use(super.{self::B::c} = super.{self::A::c}{dynamic}.-(42));
+    super.{self::A::d} = super.{self::B::d}{dynamic}.-(42);
+    self::use(super.{self::A::d} = super.{self::B::d}{dynamic}.-(42));
+    super.e = super.{self::A::e}{dynamic}.-(42);
+    self::use(super.e = super.{self::A::e}{dynamic}.-(42));
+    super.f = super.{self::A::f}{dynamic}.-(42);
+    self::use(super.f = super.{self::A::f}{dynamic}.-(42));
+    super.{self::A::g} = super.g{dynamic}.-(42);
+    self::use(super.{self::A::g} = super.g{dynamic}.-(42));
+    super.{self::A::h} = super.{self::A::h}{dynamic}.-(42);
+    self::use(super.{self::A::h} = super.{self::A::h}{dynamic}.-(42));
+    super.{self::B::i} = super.{self::A::i}{dynamic}.-(42);
+    self::use(super.{self::B::i} = super.{self::A::i}{dynamic}.-(42));
+    let final core::int* #t56 = 87 in super.{self::A::[]=}(#t56, super.{self::A::[]}(#t56){dynamic}.-(42));
+    self::use(let final core::int* #t57 = 87 in let final dynamic #t58 = super.{self::A::[]}(#t57){dynamic}.-(42) in let final void #t59 = super.{self::A::[]=}(#t57, #t58) in #t58);
+    super.m = invalid-expression "pkg/front_end/testcases/rasta/super.dart:247:13: Error: The operator '-' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '-' operator.
+    super.m -= 42;
+            ^" in super.{self::A::m}{<unresolved>}.-(42);
+    self::use(super.m = invalid-expression "pkg/front_end/testcases/rasta/super.dart:248:17: Error: The operator '-' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '-' operator.
+    use(super.m -= 42);
+                ^" in super.{self::A::m}{<unresolved>}.-(42));
+    super.{self::A::n} = invalid-expression "pkg/front_end/testcases/rasta/super.dart:249:13: Error: The operator '-' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '-' operator.
+    super.n -= 42;
+            ^" in super.{self::A::n}{<unresolved>}.-(42);
+    self::use(super.{self::A::n} = invalid-expression "pkg/front_end/testcases/rasta/super.dart:250:17: Error: The operator '-' isn't defined for the class 'void Function()'.
+Try correcting the operator to an existing operator, or defining a '-' operator.
+    use(super.n -= 42);
+                ^" in super.{self::A::n}{<unresolved>}.-(42));
+  }
+}
+static method use(dynamic x) → dynamic {
+  if(x =={core::Object::==}{(core::Object*) →* core::bool*} new core::DateTime::now().{core::DateTime::millisecondsSinceEpoch}{core::int*})
+    throw "Shouldn't happen";
+}
+static method main() → dynamic {
+  new self::C::•().{self::C::test}(){() →* dynamic};
+}
diff --git a/pkg/front_end/testcases/rasta/super_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/super_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..03f043f
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/super_initializer.dart.weak.modular.expect
@@ -0,0 +1,58 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/super_initializer.dart:15:15: Error: Can't have initializers after 'super'.
+//         field = 42;
+//               ^
+//
+// pkg/front_end/testcases/rasta/super_initializer.dart:18:15: Error: Can't have initializers after 'super'.
+//         field = 42;
+//               ^
+//
+// pkg/front_end/testcases/rasta/super_initializer.dart:21:15: Error: Can't have initializers after 'super'.
+//         field = 42;
+//               ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Super extends core::Object {
+  constructor arg0() → self::Super*
+    : super core::Object::•()
+    ;
+  constructor arg1(dynamic a) → self::Super*
+    : super core::Object::•()
+    ;
+  constructor arg2(dynamic a, dynamic b) → self::Super*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Sub extends self::Super {
+  field dynamic field;
+  constructor arg0() → self::Sub*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/rasta/super_initializer.dart:15:15: Error: Can't have initializers after 'super'.
+        field = 42;
+              ^", super self::Super::arg0()
+    ;
+  constructor arg1(dynamic a) → self::Sub*
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/rasta/super_initializer.dart:18:15: Error: Can't have initializers after 'super'.
+        field = 42;
+              ^", super self::Super::arg1(a)
+    ;
+  constructor arg2(dynamic a, dynamic b) → self::Sub*
+    : final dynamic #t3 = invalid-expression "pkg/front_end/testcases/rasta/super_initializer.dart:21:15: Error: Can't have initializers after 'super'.
+        field = 42;
+              ^", super self::Super::arg2(a, b)
+    ;
+}
diff --git a/pkg/front_end/testcases/rasta/super_mixin.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/super_mixin.dart.weak.modular.expect
new file mode 100644
index 0000000..0327051
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/super_mixin.dart.weak.modular.expect
@@ -0,0 +1,223 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "mixin_library.dart" as mix;
+
+import "org-dartlang-testcase:///mixin_library.dart" show Mixin;
+
+class Super<S extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Super<self::Super::S*>*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic
+    return 40;
+  method f() → dynamic
+    return 3;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&Super&Mixin<V extends core::Object* = dynamic> = self::Super<self::_C&Super&Mixin::V*> with mix::Mixin<self::_C&Super&Mixin::V*> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_C&Super&Mixin<self::_C&Super&Mixin::V*>*
+    : super self::Super::•()
+    ;
+  mixin-super-stub get x() → dynamic
+    return super.{mix::Mixin::x};
+  mixin-super-stub set x(dynamic value) → void
+    return super.{mix::Mixin::x} = value;
+  mixin-super-stub get y() → dynamic
+    return super.{mix::Mixin::y};
+  mixin-super-stub set y(dynamic value) → void
+    return super.{mix::Mixin::y} = value;
+  mixin-super-stub get z() → dynamic
+    return super.{mix::Mixin::z};
+  mixin-super-stub set z(dynamic value) → void
+    return super.{mix::Mixin::z} = value;
+  mixin-super-stub get t() → self::_C&Super&Mixin::V*
+    return super.{mix::Mixin::t};
+  mixin-super-stub set t(covariant-by-class self::_C&Super&Mixin::V* value) → void
+    return super.{mix::Mixin::t} = value;
+  mixin-super-stub method foo() → dynamic
+    return super.{mix::Mixin::foo}();
+  mixin-super-stub method g(covariant-by-class self::_C&Super&Mixin::V* a) → self::_C&Super&Mixin::V*
+    return super.{mix::Mixin::g}(a);
+  mixin-super-stub method h() → dynamic
+    return super.{mix::Mixin::h}();
+  mixin-super-stub method l() → dynamic
+    return super.{mix::Mixin::l}();
+  mixin-super-stub method _privateMethod() → dynamic
+    return super.{mix::Mixin::_privateMethod}();
+  mixin-super-stub method publicMethod() → dynamic
+    return super.{mix::Mixin::publicMethod}();
+}
+class C<V extends core::Object* = dynamic> extends self::_C&Super&Mixin<self::C::V*> {
+  synthetic constructor •() → self::C<self::C::V*>*
+    : super self::_C&Super&Mixin::•()
+    ;
+}
+abstract class _D&Super&Mixin = self::Super<dynamic> with mix::Mixin<dynamic> /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_D&Super&Mixin*
+    : super self::Super::•()
+    ;
+  mixin-super-stub get x() → dynamic
+    return super.{mix::Mixin::x};
+  mixin-super-stub set x(dynamic value) → void
+    return super.{mix::Mixin::x} = value;
+  mixin-super-stub get y() → dynamic
+    return super.{mix::Mixin::y};
+  mixin-super-stub set y(dynamic value) → void
+    return super.{mix::Mixin::y} = value;
+  mixin-super-stub get z() → dynamic
+    return super.{mix::Mixin::z};
+  mixin-super-stub set z(dynamic value) → void
+    return super.{mix::Mixin::z} = value;
+  mixin-super-stub get t() → dynamic
+    return super.{mix::Mixin::t};
+  mixin-super-stub set t(covariant-by-class dynamic value) → void
+    return super.{mix::Mixin::t} = value;
+  mixin-super-stub method foo() → dynamic
+    return super.{mix::Mixin::foo}();
+  mixin-super-stub method g(covariant-by-class dynamic a) → dynamic
+    return super.{mix::Mixin::g}(a);
+  mixin-super-stub method h() → dynamic
+    return super.{mix::Mixin::h}();
+  mixin-super-stub method l() → dynamic
+    return super.{mix::Mixin::l}();
+  mixin-super-stub method _privateMethod() → dynamic
+    return super.{mix::Mixin::_privateMethod}();
+  mixin-super-stub method publicMethod() → dynamic
+    return super.{mix::Mixin::publicMethod}();
+}
+class D extends self::_D&Super&Mixin {
+  synthetic constructor •() → self::D*
+    : super self::_D&Super&Mixin::•()
+    ;
+}
+class C2<V extends core::Object* = dynamic> = self::Super<self::C2::V*> with mix::Mixin<self::C2::V*> {
+  synthetic constructor •() → self::C2<self::C2::V*>*
+    : super self::Super::•()
+    ;
+  mixin-super-stub get x() → dynamic
+    return super.{mix::Mixin::x};
+  mixin-super-stub set x(dynamic value) → void
+    return super.{mix::Mixin::x} = value;
+  mixin-super-stub get y() → dynamic
+    return super.{mix::Mixin::y};
+  mixin-super-stub set y(dynamic value) → void
+    return super.{mix::Mixin::y} = value;
+  mixin-super-stub get z() → dynamic
+    return super.{mix::Mixin::z};
+  mixin-super-stub set z(dynamic value) → void
+    return super.{mix::Mixin::z} = value;
+  mixin-super-stub get t() → self::C2::V*
+    return super.{mix::Mixin::t};
+  mixin-super-stub set t(covariant-by-class self::C2::V* value) → void
+    return super.{mix::Mixin::t} = value;
+  mixin-super-stub method foo() → dynamic
+    return super.{mix::Mixin::foo}();
+  mixin-super-stub method g(covariant-by-class self::C2::V* a) → self::C2::V*
+    return super.{mix::Mixin::g}(a);
+  mixin-super-stub method h() → dynamic
+    return super.{mix::Mixin::h}();
+  mixin-super-stub method l() → dynamic
+    return super.{mix::Mixin::l}();
+  mixin-super-stub method _privateMethod() → dynamic
+    return super.{mix::Mixin::_privateMethod}();
+  mixin-super-stub method publicMethod() → dynamic
+    return super.{mix::Mixin::publicMethod}();
+}
+class D2 = self::Super<dynamic> with mix::Mixin<dynamic> {
+  synthetic constructor •() → self::D2*
+    : super self::Super::•()
+    ;
+  mixin-super-stub get x() → dynamic
+    return super.{mix::Mixin::x};
+  mixin-super-stub set x(dynamic value) → void
+    return super.{mix::Mixin::x} = value;
+  mixin-super-stub get y() → dynamic
+    return super.{mix::Mixin::y};
+  mixin-super-stub set y(dynamic value) → void
+    return super.{mix::Mixin::y} = value;
+  mixin-super-stub get z() → dynamic
+    return super.{mix::Mixin::z};
+  mixin-super-stub set z(dynamic value) → void
+    return super.{mix::Mixin::z} = value;
+  mixin-super-stub get t() → dynamic
+    return super.{mix::Mixin::t};
+  mixin-super-stub set t(covariant-by-class dynamic value) → void
+    return super.{mix::Mixin::t} = value;
+  mixin-super-stub method foo() → dynamic
+    return super.{mix::Mixin::foo}();
+  mixin-super-stub method g(covariant-by-class dynamic a) → dynamic
+    return super.{mix::Mixin::g}(a);
+  mixin-super-stub method h() → dynamic
+    return super.{mix::Mixin::h}();
+  mixin-super-stub method l() → dynamic
+    return super.{mix::Mixin::l}();
+  mixin-super-stub method _privateMethod() → dynamic
+    return super.{mix::Mixin::_privateMethod}();
+  mixin-super-stub method publicMethod() → dynamic
+    return super.{mix::Mixin::publicMethod}();
+}
+static method main() → dynamic {
+  core::print(new self::C::•<dynamic>().{self::_C&Super&Mixin::foo}(){() →* dynamic});
+  core::print(new self::C2::•<dynamic>().{self::C2::foo}(){() →* dynamic});
+}
+
+library test.mixin_library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/mixin_library.dart:16:18: Error: Superclass has no method named 'foo'.
+//   foo() => super.foo() + f();
+//                  ^^^
+//
+import self as mix;
+import "dart:core" as core;
+
+class Mixin<T extends core::Object* = dynamic> extends core::Object {
+  field dynamic x = mix::f();
+  field dynamic y = null;
+  field dynamic z = null;
+  covariant-by-class field mix::Mixin::T* t = null;
+  synthetic constructor •() → mix::Mixin<mix::Mixin::T*>*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic
+    return super.foo(){dynamic}.+(mix::f());
+  method g(covariant-by-class mix::Mixin::T* a) → mix::Mixin::T*
+    return null;
+  method h() → dynamic
+    return mix::V();
+  method l() → dynamic
+    return mix::_private();
+  method _privateMethod() → dynamic
+    return 49;
+  method publicMethod() → dynamic
+    return this.{mix::Mixin::_privateMethod}(){() →* dynamic};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method f() → dynamic
+  return 2;
+static method V() → dynamic
+  return 87;
+static method _private() → dynamic
+  return 117;
+static method foo(dynamic m) → dynamic
+  return m{dynamic}._privateMethod();
diff --git a/pkg/front_end/testcases/rasta/super_operator.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/super_operator.dart.weak.modular.expect
new file mode 100644
index 0000000..8b04b02
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/super_operator.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/super_operator.dart:22:15: Error: Superclass has no method named '[]'.
+//   g() => super[0];
+//               ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  operator +(core::String* s) → dynamic
+    return null;
+  operator [](dynamic i) → dynamic
+    return null;
+  operator []=(dynamic i, dynamic val) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+  operator +(core::String* s) → dynamic
+    return super.{self::A::+}("${s}${s}");
+  operator [](dynamic i) → dynamic
+    return super.{self::A::[]}(i);
+  operator []=(dynamic i, dynamic val) → void
+    return let final dynamic #t1 = let final dynamic #t2 = i in let final dynamic #t3 = i = #t2{dynamic}.+(1) in #t2 in let final dynamic #t4 = super.{self::A::[]}(#t1){dynamic}.+(val) in let final void #t5 = super.{self::A::[]=}(#t1, #t4) in #t4;
+}
+class Autobianchi extends core::Object {
+  synthetic constructor •() → self::Autobianchi*
+    : super core::Object::•()
+    ;
+  method g() → dynamic
+    return super.[](0);
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/rasta/supports_reflection.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/supports_reflection.dart.weak.modular.expect
new file mode 100644
index 0000000..d2d46a3
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/supports_reflection.dart.weak.modular.expect
@@ -0,0 +1,11 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::print(#C1);
+}
+
+constants  {
+  #C1 = false
+}
diff --git a/pkg/front_end/testcases/rasta/switch_execution_case_t02.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/switch_execution_case_t02.dart.weak.modular.expect
new file mode 100644
index 0000000..4a25d3e
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/switch_execution_case_t02.dart.weak.modular.expect
@@ -0,0 +1,85 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/switch_execution_case_t02.dart:35:5: Error: Switch case may fall through to the next case.
+//     case 2:  result = 2; /// static warning - case fall-through, see "Switch"
+//     ^
+//
+// pkg/front_end/testcases/rasta/switch_execution_case_t02.dart:36:5: Error: Switch case may fall through to the next case.
+//     case 3:  result = 3; /// static warning - case fall-through, see "Switch"
+//     ^
+//
+// pkg/front_end/testcases/rasta/switch_execution_case_t02.dart:46:5: Error: Switch case may fall through to the next case.
+//     case 1:
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method test(dynamic value) → dynamic {
+  dynamic result;
+  #L1:
+  switch(value) {
+    #L2:
+    case #C1:
+      {
+        result = 1;
+        break #L1;
+      }
+    #L3:
+    case #C2:
+      {
+        result = 2;
+        throw new core::FallThroughError::_create("org-dartlang-testcase:///switch_execution_case_t02.dart", 35);
+      }
+    #L4:
+    case #C3:
+      {
+        result = 3;
+        throw new core::FallThroughError::_create("org-dartlang-testcase:///switch_execution_case_t02.dart", 36);
+      }
+    #L5:
+    default:
+      {
+        result = 4;
+      }
+  }
+  return result;
+}
+static method testEmptyCases(dynamic value) → dynamic {
+  dynamic result;
+  #L6:
+  switch(value) {
+    #L7:
+    case #C1:
+    case #C2:
+      {
+        result = 1;
+        throw new core::FallThroughError::_create("org-dartlang-testcase:///switch_execution_case_t02.dart", 46);
+      }
+    #L8:
+    case #C3:
+    case #C4:
+      {
+        result = 2;
+        break #L6;
+      }
+    #L9:
+    case #C5:
+    case #C6:
+    default:
+      {}
+  }
+  return result;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 1
+  #C2 = 2
+  #C3 = 3
+  #C4 = 4
+  #C5 = 5
+  #C6 = 6
+}
diff --git a/pkg/front_end/testcases/rasta/switch_fall_through.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/switch_fall_through.dart.weak.modular.expect
new file mode 100644
index 0000000..c69920c
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/switch_fall_through.dart.weak.modular.expect
@@ -0,0 +1,99 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/switch_fall_through.dart:7:5: Error: Switch case may fall through to the next case.
+//     case 1:
+//     ^
+//
+// pkg/front_end/testcases/rasta/switch_fall_through.dart:13:5: Error: Switch case may fall through to the next case.
+//     case 2:
+//     ^
+//
+// pkg/front_end/testcases/rasta/switch_fall_through.dart:20:5: Error: Switch case may fall through to the next case.
+//     case 3:
+//     ^
+//
+// pkg/front_end/testcases/rasta/switch_fall_through.dart:26:5: Error: Switch case may fall through to the next case.
+//     case 4:
+//     ^
+//
+// pkg/front_end/testcases/rasta/switch_fall_through.dart:31:5: Error: Switch case may fall through to the next case.
+//     case 5:
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  #L1:
+  switch(1) {
+    #L2:
+    case #C1:
+      {
+        {
+          "No fall-through error needed.";
+          break #L1;
+          ;
+        }
+        throw new core::FallThroughError::_create("org-dartlang-testcase:///switch_fall_through.dart", 7);
+      }
+    #L3:
+    case #C2:
+      {
+        {
+          "Fall-through error needed.";
+          if(true) {
+            break #L1;
+          }
+        }
+        throw new core::FallThroughError::_create("org-dartlang-testcase:///switch_fall_through.dart", 13);
+      }
+    #L4:
+    case #C3:
+      {
+        try {
+          "No fall-through error needed.";
+        }
+        finally {
+          break #L1;
+        }
+        throw new core::FallThroughError::_create("org-dartlang-testcase:///switch_fall_through.dart", 20);
+      }
+    #L5:
+    case #C4:
+      {
+        try {
+          "No fall-through error needed.";
+          break #L1;
+        }
+        finally {
+        }
+        throw new core::FallThroughError::_create("org-dartlang-testcase:///switch_fall_through.dart", 26);
+      }
+    #L6:
+    case #C5:
+      {
+        try {
+          "Fall-through error needed.";
+        }
+        finally {
+        }
+        throw new core::FallThroughError::_create("org-dartlang-testcase:///switch_fall_through.dart", 31);
+      }
+    #L7:
+    case #C6:
+      {
+        "Should be last. No fall-through error, falling through allowed here.";
+      }
+  }
+}
+
+constants  {
+  #C1 = 1
+  #C2 = 2
+  #C3 = 3
+  #C4 = 4
+  #C5 = 5
+  #C6 = 10000
+}
diff --git a/pkg/front_end/testcases/rasta/this_invoke.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/this_invoke.dart.weak.modular.expect
new file mode 100644
index 0000000..37dfbd7
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/this_invoke.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method m(dynamic x) → dynamic
+    return this.{self::C::call}(x){(dynamic) →* dynamic};
+  method call(dynamic x) → dynamic
+    return 42;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::print(new self::C::•().{self::C::m}(42){(dynamic) →* dynamic});
+}
diff --git a/pkg/front_end/testcases/rasta/try_label.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/try_label.dart.weak.modular.expect
new file mode 100644
index 0000000..14f6249
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/try_label.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/try_label.dart:9:5: Error: A continue statement can't be used outside of a loop or switch statement.
+// Try removing the continue statement.
+//     continue L;
+//     ^^^^^^^^
+//
+import self as self;
+
+static method main() → dynamic {
+  #L1:
+  try {
+    break #L1;
+  }
+  finally {
+    break #L1;
+  }
+}
diff --git a/pkg/front_end/testcases/rasta/type_literals.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/type_literals.dart.weak.modular.expect
new file mode 100644
index 0000000..de13441
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/type_literals.dart.weak.modular.expect
@@ -0,0 +1,538 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:22:5: Error: Couldn't find constructor 'dynamic'.
+//     dynamic();
+//     ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:23:9: Error: Couldn't find constructor 'dynamic'.
+//     use(dynamic());
+//         ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:24:5: Error: Couldn't find constructor 'T'.
+//     T();
+//     ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:25:9: Error: Couldn't find constructor 'T'.
+//     use(T());
+//         ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:26:5: Error: Couldn't find constructor 'Func'.
+//     Func();
+//     ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:27:9: Error: Couldn't find constructor 'Func'.
+//     use(Func());
+//         ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:29:5: Error: Can't assign to a type literal.
+//     C = 42;
+//     ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:30:9: Error: Can't assign to a type literal.
+//     use(C = 42);
+//         ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:31:5: Error: Can't assign to a type literal.
+//     dynamic = 42;
+//     ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:32:9: Error: Can't assign to a type literal.
+//     use(dynamic = 42);
+//         ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:33:5: Error: Can't assign to a type literal.
+//     T = 42;
+//     ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:34:9: Error: Can't assign to a type literal.
+//     use(T = 42);
+//         ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:35:5: Error: Can't assign to a type literal.
+//     Func = 42;
+//     ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:36:9: Error: Can't assign to a type literal.
+//     use(Func = 42);
+//         ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:38:5: Error: Can't assign to a type literal.
+//     C++;
+//     ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:39:9: Error: Can't assign to a type literal.
+//     use(C++);
+//         ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:40:5: Error: Can't assign to a type literal.
+//     dynamic++;
+//     ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:41:9: Error: Can't assign to a type literal.
+//     use(dynamic++);
+//         ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:42:5: Error: Can't assign to a type literal.
+//     T++;
+//     ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:43:9: Error: Can't assign to a type literal.
+//     use(T++);
+//         ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:44:5: Error: Can't assign to a type literal.
+//     Func++;
+//     ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:45:9: Error: Can't assign to a type literal.
+//     use(Func++);
+//         ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:47:7: Error: Can't assign to a type literal.
+//     ++C;
+//       ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:48:11: Error: Can't assign to a type literal.
+//     use(++C);
+//           ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:49:7: Error: Can't assign to a type literal.
+//     ++dynamic;
+//       ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:50:11: Error: Can't assign to a type literal.
+//     use(++dynamic);
+//           ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:51:7: Error: Can't assign to a type literal.
+//     ++T;
+//       ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:52:11: Error: Can't assign to a type literal.
+//     use(++T);
+//           ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:53:7: Error: Can't assign to a type literal.
+//     ++Func;
+//       ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:54:11: Error: Can't assign to a type literal.
+//     use(++Func);
+//           ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:56:5: Error: Can't assign to a type literal.
+//     C--;
+//     ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:57:9: Error: Can't assign to a type literal.
+//     use(C--);
+//         ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:58:5: Error: Can't assign to a type literal.
+//     dynamic--;
+//     ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:59:9: Error: Can't assign to a type literal.
+//     use(dynamic--);
+//         ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:60:5: Error: Can't assign to a type literal.
+//     T--;
+//     ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:61:9: Error: Can't assign to a type literal.
+//     use(T--);
+//         ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:62:5: Error: Can't assign to a type literal.
+//     Func--;
+//     ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:63:9: Error: Can't assign to a type literal.
+//     use(Func--);
+//         ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:65:7: Error: Can't assign to a type literal.
+//     --C;
+//       ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:66:11: Error: Can't assign to a type literal.
+//     use(--C);
+//           ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:67:7: Error: Can't assign to a type literal.
+//     --dynamic;
+//       ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:68:11: Error: Can't assign to a type literal.
+//     use(--dynamic);
+//           ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:69:7: Error: Can't assign to a type literal.
+//     --T;
+//       ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:70:11: Error: Can't assign to a type literal.
+//     use(--T);
+//           ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:71:7: Error: Can't assign to a type literal.
+//     --Func;
+//       ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:72:11: Error: Can't assign to a type literal.
+//     use(--Func);
+//           ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:74:5: Error: Can't assign to a type literal.
+//     C ??= 42;
+//     ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:75:9: Error: Can't assign to a type literal.
+//     use(C ??= 42);
+//         ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:76:5: Error: Can't assign to a type literal.
+//     dynamic ??= 42;
+//     ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:77:9: Error: Can't assign to a type literal.
+//     use(dynamic ??= 42);
+//         ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:78:5: Error: Can't assign to a type literal.
+//     T ??= 42;
+//     ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:79:9: Error: Can't assign to a type literal.
+//     use(T ??= 42);
+//         ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:80:5: Error: Can't assign to a type literal.
+//     Func ??= 42;
+//     ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:81:9: Error: Can't assign to a type literal.
+//     use(Func ??= 42);
+//         ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:83:5: Error: Can't assign to a type literal.
+//     C += 42;
+//     ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:84:9: Error: Can't assign to a type literal.
+//     use(C += 42);
+//         ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:85:5: Error: Can't assign to a type literal.
+//     dynamic += 42;
+//     ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:86:9: Error: Can't assign to a type literal.
+//     use(dynamic += 42);
+//         ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:87:5: Error: Can't assign to a type literal.
+//     T += 42;
+//     ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:88:9: Error: Can't assign to a type literal.
+//     use(T += 42);
+//         ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:89:5: Error: Can't assign to a type literal.
+//     Func += 42;
+//     ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:90:9: Error: Can't assign to a type literal.
+//     use(Func += 42);
+//         ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:92:5: Error: Can't assign to a type literal.
+//     C -= 42;
+//     ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:93:9: Error: Can't assign to a type literal.
+//     use(C -= 42);
+//         ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:94:5: Error: Can't assign to a type literal.
+//     dynamic -= 42;
+//     ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:95:9: Error: Can't assign to a type literal.
+//     use(dynamic -= 42);
+//         ^^^^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:96:5: Error: Can't assign to a type literal.
+//     T -= 42;
+//     ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:97:9: Error: Can't assign to a type literal.
+//     use(T -= 42);
+//         ^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:98:5: Error: Can't assign to a type literal.
+//     Func -= 42;
+//     ^^^^
+//
+// pkg/front_end/testcases/rasta/type_literals.dart:99:9: Error: Can't assign to a type literal.
+//     use(Func -= 42);
+//         ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef Func = () →* void;
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method test() → dynamic {
+    #C1;
+    self::use(#C1);
+    #C2;
+    self::use(#C2);
+    self::C::T*;
+    self::use(self::C::T*);
+    #C3;
+    self::use(#C3);
+    new self::C::•<dynamic>();
+    self::use(new self::C::•<dynamic>());
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:22:5: Error: Couldn't find constructor 'dynamic'.
+    dynamic();
+    ^^^^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:23:9: Error: Couldn't find constructor 'dynamic'.
+    use(dynamic());
+        ^^^^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:24:5: Error: Couldn't find constructor 'T'.
+    T();
+    ^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:25:9: Error: Couldn't find constructor 'T'.
+    use(T());
+        ^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:26:5: Error: Couldn't find constructor 'Func'.
+    Func();
+    ^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:27:9: Error: Couldn't find constructor 'Func'.
+    use(Func());
+        ^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:29:5: Error: Can't assign to a type literal.
+    C = 42;
+    ^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:30:9: Error: Can't assign to a type literal.
+    use(C = 42);
+        ^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:31:5: Error: Can't assign to a type literal.
+    dynamic = 42;
+    ^^^^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:32:9: Error: Can't assign to a type literal.
+    use(dynamic = 42);
+        ^^^^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:33:5: Error: Can't assign to a type literal.
+    T = 42;
+    ^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:34:9: Error: Can't assign to a type literal.
+    use(T = 42);
+        ^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:35:5: Error: Can't assign to a type literal.
+    Func = 42;
+    ^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:36:9: Error: Can't assign to a type literal.
+    use(Func = 42);
+        ^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:38:5: Error: Can't assign to a type literal.
+    C++;
+    ^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:39:9: Error: Can't assign to a type literal.
+    use(C++);
+        ^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:40:5: Error: Can't assign to a type literal.
+    dynamic++;
+    ^^^^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:41:9: Error: Can't assign to a type literal.
+    use(dynamic++);
+        ^^^^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:42:5: Error: Can't assign to a type literal.
+    T++;
+    ^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:43:9: Error: Can't assign to a type literal.
+    use(T++);
+        ^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:44:5: Error: Can't assign to a type literal.
+    Func++;
+    ^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:45:9: Error: Can't assign to a type literal.
+    use(Func++);
+        ^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:47:7: Error: Can't assign to a type literal.
+    ++C;
+      ^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:48:11: Error: Can't assign to a type literal.
+    use(++C);
+          ^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:49:7: Error: Can't assign to a type literal.
+    ++dynamic;
+      ^^^^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:50:11: Error: Can't assign to a type literal.
+    use(++dynamic);
+          ^^^^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:51:7: Error: Can't assign to a type literal.
+    ++T;
+      ^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:52:11: Error: Can't assign to a type literal.
+    use(++T);
+          ^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:53:7: Error: Can't assign to a type literal.
+    ++Func;
+      ^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:54:11: Error: Can't assign to a type literal.
+    use(++Func);
+          ^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:56:5: Error: Can't assign to a type literal.
+    C--;
+    ^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:57:9: Error: Can't assign to a type literal.
+    use(C--);
+        ^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:58:5: Error: Can't assign to a type literal.
+    dynamic--;
+    ^^^^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:59:9: Error: Can't assign to a type literal.
+    use(dynamic--);
+        ^^^^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:60:5: Error: Can't assign to a type literal.
+    T--;
+    ^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:61:9: Error: Can't assign to a type literal.
+    use(T--);
+        ^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:62:5: Error: Can't assign to a type literal.
+    Func--;
+    ^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:63:9: Error: Can't assign to a type literal.
+    use(Func--);
+        ^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:65:7: Error: Can't assign to a type literal.
+    --C;
+      ^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:66:11: Error: Can't assign to a type literal.
+    use(--C);
+          ^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:67:7: Error: Can't assign to a type literal.
+    --dynamic;
+      ^^^^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:68:11: Error: Can't assign to a type literal.
+    use(--dynamic);
+          ^^^^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:69:7: Error: Can't assign to a type literal.
+    --T;
+      ^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:70:11: Error: Can't assign to a type literal.
+    use(--T);
+          ^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:71:7: Error: Can't assign to a type literal.
+    --Func;
+      ^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:72:11: Error: Can't assign to a type literal.
+    use(--Func);
+          ^^^^");
+    #C1 == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:74:5: Error: Can't assign to a type literal.
+    C ??= 42;
+    ^" : null;
+    self::use(let final core::Type* #t1 = #C1 in #t1 == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:75:9: Error: Can't assign to a type literal.
+    use(C ??= 42);
+        ^" : #t1);
+    #C2 == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:76:5: Error: Can't assign to a type literal.
+    dynamic ??= 42;
+    ^^^^^^^" : null;
+    self::use(let final core::Type* #t2 = #C2 in #t2 == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:77:9: Error: Can't assign to a type literal.
+    use(dynamic ??= 42);
+        ^^^^^^^" : #t2);
+    self::C::T* == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:78:5: Error: Can't assign to a type literal.
+    T ??= 42;
+    ^" : null;
+    self::use(let final core::Type* #t3 = self::C::T* in #t3 == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:79:9: Error: Can't assign to a type literal.
+    use(T ??= 42);
+        ^" : #t3);
+    #C3 == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:80:5: Error: Can't assign to a type literal.
+    Func ??= 42;
+    ^^^^" : null;
+    self::use(let final core::Type* #t4 = #C3 in #t4 == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:81:9: Error: Can't assign to a type literal.
+    use(Func ??= 42);
+        ^^^^" : #t4);
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:83:5: Error: Can't assign to a type literal.
+    C += 42;
+    ^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:84:9: Error: Can't assign to a type literal.
+    use(C += 42);
+        ^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:85:5: Error: Can't assign to a type literal.
+    dynamic += 42;
+    ^^^^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:86:9: Error: Can't assign to a type literal.
+    use(dynamic += 42);
+        ^^^^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:87:5: Error: Can't assign to a type literal.
+    T += 42;
+    ^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:88:9: Error: Can't assign to a type literal.
+    use(T += 42);
+        ^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:89:5: Error: Can't assign to a type literal.
+    Func += 42;
+    ^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:90:9: Error: Can't assign to a type literal.
+    use(Func += 42);
+        ^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:92:5: Error: Can't assign to a type literal.
+    C -= 42;
+    ^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:93:9: Error: Can't assign to a type literal.
+    use(C -= 42);
+        ^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:94:5: Error: Can't assign to a type literal.
+    dynamic -= 42;
+    ^^^^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:95:9: Error: Can't assign to a type literal.
+    use(dynamic -= 42);
+        ^^^^^^^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:96:5: Error: Can't assign to a type literal.
+    T -= 42;
+    ^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:97:9: Error: Can't assign to a type literal.
+    use(T -= 42);
+        ^");
+    invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:98:5: Error: Can't assign to a type literal.
+    Func -= 42;
+    ^^^^";
+    self::use(invalid-expression "pkg/front_end/testcases/rasta/type_literals.dart:99:9: Error: Can't assign to a type literal.
+    use(Func -= 42);
+        ^^^^");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method use(dynamic x) → dynamic {
+  if(x =={core::Object::==}{(core::Object*) →* core::bool*} new core::DateTime::now().{core::DateTime::millisecondsSinceEpoch}{core::int*})
+    throw "Shouldn't happen";
+}
+static method main() → dynamic {
+  new self::C::•<dynamic>().{self::C::test}(){() →* dynamic};
+}
+
+constants  {
+  #C1 = TypeLiteralConstant(self::C<dynamic>*)
+  #C2 = TypeLiteralConstant(dynamic)
+  #C3 = TypeLiteralConstant(() →* void)
+}
diff --git a/pkg/front_end/testcases/rasta/type_with_parse_error.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/type_with_parse_error.dart.weak.modular.expect
new file mode 100644
index 0000000..3d3d7f0
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/type_with_parse_error.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/type_with_parse_error.dart:21:7: Error: Expected ';' after this.
+//   int i
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic {
+    new self::B::•<self::A*>();
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B<T extends core::Object* = dynamic> extends core::Object {
+  field core::int* i = null;
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::B::•<self::A*>();
+}
diff --git a/pkg/front_end/testcases/rasta/typedef.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/typedef.dart.weak.modular.expect
new file mode 100644
index 0000000..72932b9
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/typedef.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/typedef.dart:9:3: Error: Can't assign to a type literal.
+//   Foo = null;
+//   ^^^
+//
+// pkg/front_end/testcases/rasta/typedef.dart:10:3: Error: Can't assign to a type literal.
+//   Foo ??= null;
+//   ^^^
+//
+// pkg/front_end/testcases/rasta/typedef.dart:11:3: Error: Couldn't find constructor 'Foo'.
+//   Foo();
+//   ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef Foo = () →* void;
+static method main() → dynamic {
+  core::print(#C1);
+  invalid-expression "pkg/front_end/testcases/rasta/typedef.dart:9:3: Error: Can't assign to a type literal.
+  Foo = null;
+  ^^^";
+  #C1 == null ?{invalid-type} invalid-expression "pkg/front_end/testcases/rasta/typedef.dart:10:3: Error: Can't assign to a type literal.
+  Foo ??= null;
+  ^^^" : null;
+  invalid-expression "pkg/front_end/testcases/rasta/typedef.dart:11:3: Error: Couldn't find constructor 'Foo'.
+  Foo();
+  ^^^";
+}
+
+constants  {
+  #C1 = TypeLiteralConstant(() →* void)
+}
diff --git a/pkg/front_end/testcases/rasta/unresolved.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/unresolved.dart.weak.modular.expect
new file mode 100644
index 0000000..39e56f4
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/unresolved.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/unresolved.dart:6:7: Error: Couldn't find constructor 'Missing'.
+//   new Missing();
+//       ^^^^^^^
+//
+import self as self;
+
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/rasta/unresolved.dart:6:7: Error: Couldn't find constructor 'Missing'.
+  new Missing();
+      ^^^^^^^";
+}
diff --git a/pkg/front_end/testcases/rasta/unresolved_constructor.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/unresolved_constructor.dart.weak.modular.expect
new file mode 100644
index 0000000..fc47b33
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/unresolved_constructor.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/unresolved_constructor.dart:10:10: Error: Too few positional arguments: 2 required, 0 given.
+//   new Foo();
+//          ^
+// pkg/front_end/testcases/rasta/unresolved_constructor.dart:6:3: Context: Found this candidate, but the arguments don't match.
+//   Foo(x, y);
+//   ^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_constructor.dart:11:11: Error: Couldn't find constructor 'Foo.notHere'.
+//   new Foo.notHere();
+//           ^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  constructor •(dynamic x, dynamic y) → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/rasta/unresolved_constructor.dart:10:10: Error: Too few positional arguments: 2 required, 0 given.
+  new Foo();
+         ^";
+  invalid-expression "pkg/front_end/testcases/rasta/unresolved_constructor.dart:11:11: Error: Couldn't find constructor 'Foo.notHere'.
+  new Foo.notHere();
+          ^^^^^^^";
+}
diff --git a/pkg/front_end/testcases/rasta/unresolved_for_in.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/unresolved_for_in.dart.weak.modular.expect
new file mode 100644
index 0000000..1600ec3
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/unresolved_for_in.dart.weak.modular.expect
@@ -0,0 +1,209 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:14:10: Error: Can't assign to a type literal.
+//     for (Fisk in x) {
+//          ^^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:18:13: Error: A prefix can't be used as an expression.
+//       print(collection);
+//             ^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:17:10: Error: A prefix can't be used as an expression.
+//     for (collection in x) {
+//          ^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:20:10: Error: Can't assign to a type literal.
+//     for (VoidFunction in x) {
+//          ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:23:10: Error: Expected an identifier, but got '1'.
+// Try inserting an identifier before '1'.
+//     for (1 in x) {
+//          ^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:23:10: Error: Can't assign to this, so it can't be used in a for-in loop.
+//     for (1 in x) {
+//          ^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:11:10: Error: The setter 'key' isn't defined for the class 'Fisk'.
+//  - 'Fisk' is from 'pkg/front_end/testcases/rasta/unresolved_for_in.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'key'.
+//     for (key in x) {
+//          ^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:12:13: Error: The getter 'key' isn't defined for the class 'Fisk'.
+//  - 'Fisk' is from 'pkg/front_end/testcases/rasta/unresolved_for_in.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'key'.
+//       print(key);
+//             ^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:24:13: Error: The getter 'key' isn't defined for the class 'Fisk'.
+//  - 'Fisk' is from 'pkg/front_end/testcases/rasta/unresolved_for_in.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'key'.
+//       print(key);
+//             ^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:32:11: Error: Undefined name 'key'.
+//     print(key);
+//           ^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:31:8: Error: Setter not found: 'key'.
+//   for (key in arguments) {
+//        ^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:34:8: Error: Can't assign to a type literal.
+//   for (Fisk in arguments) {
+//        ^^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:38:11: Error: A prefix can't be used as an expression.
+//     print(collection);
+//           ^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:37:8: Error: A prefix can't be used as an expression.
+//   for (collection in arguments) {
+//        ^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:40:8: Error: Can't assign to a type literal.
+//   for (VoidFunction in arguments) {
+//        ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:43:8: Error: Expected an identifier, but got '1'.
+// Try inserting an identifier before '1'.
+//   for (1 in arguments) {
+//        ^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:44:11: Error: Undefined name 'key'.
+//     print(key);
+//           ^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_for_in.dart:43:8: Error: Can't assign to this, so it can't be used in a for-in loop.
+//   for (1 in arguments) {
+//        ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "dart:collection" as collection;
+
+typedef VoidFunction = () →* void;
+class Fisk extends core::Object {
+  synthetic constructor •() → self::Fisk*
+    : super core::Object::•()
+    ;
+  method it1(dynamic x) → dynamic {
+    for (final dynamic #t1 in x as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:11:10: Error: The setter 'key' isn't defined for the class 'Fisk'.
+ - 'Fisk' is from 'pkg/front_end/testcases/rasta/unresolved_for_in.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'key'.
+    for (key in x) {
+         ^^^" in this{<unresolved>}.key = invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:11:10: Error: The setter 'key' isn't defined for the class 'Fisk'.
+ - 'Fisk' is from 'pkg/front_end/testcases/rasta/unresolved_for_in.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'key'.
+    for (key in x) {
+         ^^^";
+      core::print(invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:12:13: Error: The getter 'key' isn't defined for the class 'Fisk'.
+ - 'Fisk' is from 'pkg/front_end/testcases/rasta/unresolved_for_in.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'key'.
+      print(key);
+            ^^^" in this{<unresolved>}.key);
+    }
+    for (final dynamic #t2 in x as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:14:10: Error: Can't assign to a type literal.
+    for (Fisk in x) {
+         ^^^^";
+      core::print(#C1);
+    }
+    for (final dynamic #t3 in x as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:17:10: Error: A prefix can't be used as an expression.
+    for (collection in x) {
+         ^^^^^^^^^^";
+      core::print(invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:18:13: Error: A prefix can't be used as an expression.
+      print(collection);
+            ^^^^^^^^^^");
+    }
+    for (final dynamic #t4 in x as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:20:10: Error: Can't assign to a type literal.
+    for (VoidFunction in x) {
+         ^^^^^^^^^^^^";
+      core::print(#C2);
+    }
+    {
+      invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:23:10: Error: Can't assign to this, so it can't be used in a for-in loop.
+    for (1 in x) {
+         ^";
+      for (final dynamic #t5 in x as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+        invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:23:10: Error: Can't assign to this, so it can't be used in a for-in loop.
+    for (1 in x) {
+         ^";
+        1;
+        core::print(invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:24:13: Error: The getter 'key' isn't defined for the class 'Fisk'.
+ - 'Fisk' is from 'pkg/front_end/testcases/rasta/unresolved_for_in.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'key'.
+      print(key);
+            ^^^" in this{<unresolved>}.key);
+      }
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main(dynamic arguments) → dynamic {
+  new self::Fisk::•();
+  for (final dynamic #t6 in arguments as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+    invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:31:8: Error: Setter not found: 'key'.
+  for (key in arguments) {
+       ^^^";
+    core::print(invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:32:11: Error: Undefined name 'key'.
+    print(key);
+          ^^^");
+  }
+  for (final dynamic #t7 in arguments as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+    invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:34:8: Error: Can't assign to a type literal.
+  for (Fisk in arguments) {
+       ^^^^";
+    core::print(#C1);
+  }
+  for (final dynamic #t8 in arguments as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+    invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:37:8: Error: A prefix can't be used as an expression.
+  for (collection in arguments) {
+       ^^^^^^^^^^";
+    core::print(invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:38:11: Error: A prefix can't be used as an expression.
+    print(collection);
+          ^^^^^^^^^^");
+  }
+  for (final dynamic #t9 in arguments as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+    invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:40:8: Error: Can't assign to a type literal.
+  for (VoidFunction in arguments) {
+       ^^^^^^^^^^^^";
+    core::print(#C2);
+  }
+  {
+    invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:43:8: Error: Can't assign to this, so it can't be used in a for-in loop.
+  for (1 in arguments) {
+       ^";
+    for (final dynamic #t10 in arguments as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:43:8: Error: Can't assign to this, so it can't be used in a for-in loop.
+  for (1 in arguments) {
+       ^";
+      1;
+      core::print(invalid-expression "pkg/front_end/testcases/rasta/unresolved_for_in.dart:44:11: Error: Undefined name 'key'.
+    print(key);
+          ^^^");
+    }
+  }
+}
+
+constants  {
+  #C1 = TypeLiteralConstant(self::Fisk*)
+  #C2 = TypeLiteralConstant(() →* void)
+}
diff --git a/pkg/front_end/testcases/rasta/unresolved_recovery.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/unresolved_recovery.dart.weak.modular.expect
new file mode 100644
index 0000000..8bd61ac
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/unresolved_recovery.dart.weak.modular.expect
@@ -0,0 +1,81 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/rasta/unresolved_recovery.dart:7:10: Error: Superclass has no method named '[]='.
+//     super[4] = 42;
+//          ^
+//
+// pkg/front_end/testcases/rasta/unresolved_recovery.dart:9:17: Error: Superclass has no method named '[]'.
+//     return super[2];
+//                 ^
+//
+// pkg/front_end/testcases/rasta/unresolved_recovery.dart:8:10: Error: Superclass has no method named '[]'.
+//     super[4] += 5;
+//          ^
+//
+// pkg/front_end/testcases/rasta/unresolved_recovery.dart:8:10: Error: Superclass has no method named '[]='.
+//     super[4] += 5;
+//          ^
+//
+// pkg/front_end/testcases/rasta/unresolved_recovery.dart:20:3: Error: 'on' isn't a type.
+//   on Exception catch (e) { }
+//   ^^
+//
+// pkg/front_end/testcases/rasta/unresolved_recovery.dart:20:6: Error: Expected ';' after this.
+//   on Exception catch (e) { }
+//      ^^^^^^^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_recovery.dart:20:16: Error: 'catch' can't be used as an identifier because it's a keyword.
+// Try renaming this to be an identifier that isn't a keyword.
+//   on Exception catch (e) { }
+//                ^^^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_recovery.dart:20:23: Error: Undefined name 'e'.
+//   on Exception catch (e) { }
+//                       ^
+//
+// pkg/front_end/testcases/rasta/unresolved_recovery.dart:20:16: Error: Method not found: 'catch'.
+//   on Exception catch (e) { }
+//                ^^^^^
+//
+// pkg/front_end/testcases/rasta/unresolved_recovery.dart:20:24: Error: Expected ';' after this.
+//   on Exception catch (e) { }
+//                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class E extends core::Object {
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic {
+    super.[]=(4, 42);
+    let final core::int* #t1 = 4 in invalid-expression "pkg/front_end/testcases/rasta/unresolved_recovery.dart:8:10: Error: Superclass has no method named '[]='.
+    super[4] += 5;
+         ^";
+    return super.[](2);
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method beforeTestMissingTry() → dynamic {
+  self::testMissingTry();
+}
+static method testMissingTry() → dynamic {
+  invalid-type Exception;
+  invalid-expression "pkg/front_end/testcases/rasta/unresolved_recovery.dart:20:16: Error: Method not found: 'catch'.
+  on Exception catch (e) { }
+               ^^^^^";
+  {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/rasta/unsupported_platform_library.dart.weak.modular.expect b/pkg/front_end/testcases/rasta/unsupported_platform_library.dart.weak.modular.expect
new file mode 100644
index 0000000..7651a58
--- /dev/null
+++ b/pkg/front_end/testcases/rasta/unsupported_platform_library.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+//
+// Problems outside component:
+//
+// pkg/front_end/testcases/rasta/unsupported_platform_library.dart:5:8: Error: Not found: 'dart:html'
+// import 'dart:html';
+//        ^
+//
+library;
+import self as self;
+
+import "dart:html";
+import "dart:io";
+
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/ambiguous_builder_01.dart.weak.modular.expect b/pkg/front_end/testcases/regress/ambiguous_builder_01.dart.weak.modular.expect
new file mode 100644
index 0000000..d9c6c13
--- /dev/null
+++ b/pkg/front_end/testcases/regress/ambiguous_builder_01.dart.weak.modular.expect
@@ -0,0 +1,72 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/ambiguous_builder_01.dart:5:1: Error: A function declaration needs an explicit list of parameters.
+// Try adding a parameter list to the function declaration.
+// x.y = 42;
+// ^
+//
+// pkg/front_end/testcases/regress/ambiguous_builder_01.dart:5:2: Error: Expected '{' before this.
+// x.y = 42;
+//  ^
+//
+// pkg/front_end/testcases/regress/ambiguous_builder_01.dart:5:2: Error: Expected a declaration, but got '.'.
+// x.y = 42;
+//  ^
+//
+// pkg/front_end/testcases/regress/ambiguous_builder_01.dart:5:3: Error: Variables must be declared using the keywords 'const', 'final', 'var' or a type name.
+// Try adding the name of the type of the variable or the keyword 'var'.
+// x.y = 42;
+//   ^
+//
+// pkg/front_end/testcases/regress/ambiguous_builder_01.dart:6:1: Error: A function declaration needs an explicit list of parameters.
+// Try adding a parameter list to the function declaration.
+// x.z = true;
+// ^
+//
+// pkg/front_end/testcases/regress/ambiguous_builder_01.dart:6:2: Error: Expected '{' before this.
+// x.z = true;
+//  ^
+//
+// pkg/front_end/testcases/regress/ambiguous_builder_01.dart:6:1: Error: 'x' is already declared in this scope.
+// x.z = true;
+// ^
+// pkg/front_end/testcases/regress/ambiguous_builder_01.dart:5:1: Context: Previous declaration of 'x'.
+// x.y = 42;
+// ^
+//
+// pkg/front_end/testcases/regress/ambiguous_builder_01.dart:6:2: Error: Expected a declaration, but got '.'.
+// x.z = true;
+//  ^
+//
+// pkg/front_end/testcases/regress/ambiguous_builder_01.dart:6:3: Error: Variables must be declared using the keywords 'const', 'final', 'var' or a type name.
+// Try adding the name of the type of the variable or the keyword 'var'.
+// x.z = true;
+//   ^
+//
+// pkg/front_end/testcases/regress/ambiguous_builder_01.dart:8:7: Error: Can't use 'x' because it is declared more than once.
+//   if (x != null) {}
+//       ^
+//
+// pkg/front_end/testcases/regress/ambiguous_builder_01.dart:9:15: Error: Can't use 'x' because it is declared more than once.
+//   if (null != x) {}
+//               ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field core::int* y = 42;
+static field core::bool* z = true;
+static method x() → dynamic {}
+static method foo() → void {
+  if(!(invalid-expression "pkg/front_end/testcases/regress/ambiguous_builder_01.dart:8:7: Error: Can't use 'x' because it is declared more than once.
+  if (x != null) {}
+      ^" == null)) {
+  }
+  if(!(invalid-expression "pkg/front_end/testcases/regress/ambiguous_builder_01.dart:9:15: Error: Can't use 'x' because it is declared more than once.
+  if (null != x) {}
+              ^" == null)) {
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_29937.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29937.dart.weak.modular.expect
new file mode 100644
index 0000000..07a6b9a7
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29937.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29937.dart:6:4: Error: A function expression can't have a name.
+//   [f() {}];
+//    ^
+//
+import self as self;
+
+static method main() → dynamic {
+  <() →* Null>[let final () →* Null f = () → Null {} in f];
+}
diff --git a/pkg/front_end/testcases/regress/issue_29940.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29940.dart.weak.modular.expect
new file mode 100644
index 0000000..eee3efe
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29940.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29940.dart:7:3: Error: 'a.b' can't be used as a type because 'a' doesn't refer to an import prefix.
+//   a.b c = null;
+//   ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::String* a = "";
+  invalid-type c = null;
+}
diff --git a/pkg/front_end/testcases/regress/issue_29941.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29941.dart.weak.modular.expect
new file mode 100644
index 0000000..82b995b
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29941.dart.weak.modular.expect
@@ -0,0 +1,20 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29941.dart:7:5: Error: Expected an identifier, but got '""'.
+// Try inserting an identifier before '""'.
+//   a."";
+//     ^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method bad() → dynamic {
+  core::String* a = "";
+  invalid-expression "pkg/front_end/testcases/regress/issue_29941.dart:7:5: Error: Expected an identifier, but got '\"\"'.
+Try inserting an identifier before '\"\"'.
+  a.\"\";
+    ^^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_29942.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29942.dart.weak.modular.expect
new file mode 100644
index 0000000..f545925
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29942.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29942.dart:8:5: Error: Expected a function body or '=>'.
+// Try adding {}.
+// f() =
+//     ^
+//
+// pkg/front_end/testcases/regress/issue_29942.dart:10:1: Error: A function expression can't have a name.
+// h() => null;
+// ^
+//
+import self as self;
+
+static method main() → dynamic {}
+static method f() → dynamic
+  return let final () →* Null h = () → Null => null in h;
diff --git a/pkg/front_end/testcases/regress/issue_29943.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29943.dart.weak.modular.expect
new file mode 100644
index 0000000..cc07a5e
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29943.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29943.dart:6:5: Error: Expected an identifier, but got '('.
+// Try inserting an identifier before '('.
+//   x.(null);
+//     ^
+//
+import self as self;
+
+static method bad() → dynamic {
+  invalid-expression "pkg/front_end/testcases/regress/issue_29943.dart:6:5: Error: Expected an identifier, but got '('.
+Try inserting an identifier before '('.
+  x.(null);
+    ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_29944.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29944.dart.weak.modular.expect
new file mode 100644
index 0000000..4ad1117
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29944.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29944.dart:7:7: Error: A class member can't have the same name as the enclosing class.
+// Try renaming the member.
+//   var C;
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field dynamic C = null;
+  constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::C::•();
+}
diff --git a/pkg/front_end/testcases/regress/issue_29945.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29945.dart.weak.modular.expect
new file mode 100644
index 0000000..038a3a7
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29945.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29945.dart:6:3: Error: 's.bool' can't be used as a type because 's' isn't defined.
+//   s.bool x = null;
+//   ^^^^^^
+//
+import self as self;
+
+static method main() → dynamic {
+  invalid-type x = null;
+}
diff --git a/pkg/front_end/testcases/regress/issue_29975.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29975.dart.weak.modular.expect
new file mode 100644
index 0000000..cb75715
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29975.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29975.dart:6:14: Error: 'F' is already declared in this scope.
+// typedef void F();
+//              ^
+// pkg/front_end/testcases/regress/issue_29975.dart:5:14: Context: Previous declaration of 'F'.
+// typedef void F();
+//              ^
+//
+import self as self;
+
+typedef F = () →* void;
+static method main() → void {}
diff --git a/pkg/front_end/testcases/regress/issue_29976.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29976.dart.weak.modular.expect
new file mode 100644
index 0000000..b65bb80
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29976.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29976.dart:9:14: Error: The non-ASCII character 'é' (U+00E9) can't be used in identifiers, only in strings and comments.
+// Try using an US-ASCII letter, a digit, '_' (an underscore), or '$' (a dollar sign).
+//     "x${x*"'"é'}x
+//              ^
+//
+// pkg/front_end/testcases/regress/issue_29976.dart:9:15: Error: String starting with ' must end with '.
+//     "x${x*"'"é'}x
+//               ^^^
+//
+// pkg/front_end/testcases/regress/issue_29976.dart:9:7: Error: Can't find '}' to match '${'.
+//     "x${x*"'"é'}x
+//       ^
+//
+// pkg/front_end/testcases/regress/issue_29976.dart:9:5: Error: String starting with " must end with ".
+//     "x${x*"'"é'}x
+//     ^^^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/regress/issue_29976.dart:12:1: Error: Expected a declaration, but got ''.
+//
+// pkg/front_end/testcases/regress/issue_29976.dart:9:14: Error: Expected '}' before this.
+//     "x${x*"'"é'}x
+//              ^
+//
+// pkg/front_end/testcases/regress/issue_29976.dart:10:3: Error: Expected a String, but got ')'.
+//   )
+//   ^
+//
+// pkg/front_end/testcases/regress/issue_29976.dart:8:3: Error: Method not found: 'f'.
+//   f(
+//   ^
+//
+// pkg/front_end/testcases/regress/issue_29976.dart:10:3: Error: Expected ';' after this.
+//   )
+//   ^
+//
+import self as self;
+
+static get x() → dynamic
+  return null;
+static method main() → void {
+  invalid-expression "pkg/front_end/testcases/regress/issue_29976.dart:8:3: Error: Method not found: 'f'.
+  f(
+  ^";
+}
diff --git a/pkg/front_end/testcases/regress/issue_29977.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29977.dart.weak.modular.expect
new file mode 100644
index 0000000..b0dc750
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29977.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29977.dart:5:19: Error: Couldn't parse URI 'data:async':
+//   Invalid MIME type.
+// import 'data:async';
+//                   ^
+//
+import self as self;
+
+import "org-dartlang-malformed-uri:?data%3Aasync";
+
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29977.dart:5:8: Error: Expected a URI.
+// import 'data:async';
+//        ^
+//
+import self as self2;
diff --git a/pkg/front_end/testcases/regress/issue_29978.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29978.dart.weak.modular.expect
new file mode 100644
index 0000000..a166dcf
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29978.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29978.dart:8:13: Error: A function expression can't have a name.
+//   foo(null, f() {});
+//             ^
+//
+import self as self;
+
+static method foo(dynamic a, dynamic b) → dynamic
+  return null;
+static method main() → dynamic {
+  self::foo(null, let final () →* Null f = () → Null {} in f);
+}
diff --git a/pkg/front_end/testcases/regress/issue_29979.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29979.dart.weak.modular.expect
new file mode 100644
index 0000000..66cb15d
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29979.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29979.dart:6:4: Error: A function expression can't have a name.
+//   (f() {})();
+//    ^
+//
+import self as self;
+
+static method main() → dynamic {
+  (let final () →* Null f = () → Null {} in f)(){() →* Null};
+}
diff --git a/pkg/front_end/testcases/regress/issue_29980.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29980.dart.weak.modular.expect
new file mode 100644
index 0000000..1e683cf
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29980.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29980.dart:6:3: Error: 'x.y' can't be used as a type because 'x' isn't defined.
+//   x.y z;
+//   ^^^
+//
+import self as self;
+
+static method main() → dynamic {
+  invalid-type z;
+}
diff --git a/pkg/front_end/testcases/regress/issue_29981.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29981.dart.weak.modular.expect
new file mode 100644
index 0000000..d56e571
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29981.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29981.dart:6:3: Error: Expected 1 type arguments.
+//   C<String, String> field;
+//   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  field invalid-type field = null;
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::print(new self::C::•<dynamic>());
+}
diff --git a/pkg/front_end/testcases/regress/issue_29982.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29982.dart.weak.modular.expect
new file mode 100644
index 0000000..382c715
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29982.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29982.dart:7:15: Error: The non-ASCII character 'é' (U+00E9) can't be used in identifiers, only in strings and comments.
+// Try using an US-ASCII letter, a digit, '_' (an underscore), or '$' (a dollar sign).
+//   print('${eh[éh']}');
+//               ^
+//
+// pkg/front_end/testcases/regress/issue_29982.dart:7:14: Error: Can't find ']' to match '['.
+//   print('${eh[éh']}');
+//              ^
+//
+// pkg/front_end/testcases/regress/issue_29982.dart:7:10: Error: Can't find '}' to match '${'.
+//   print('${eh[éh']}');
+//          ^
+//
+// pkg/front_end/testcases/regress/issue_29982.dart:7:11: Error: String starting with ' must end with '.
+//   print('${eh[éh']}');
+//           ^^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/regress/issue_29982.dart:9:1: Error: Expected a declaration, but got ''.
+//
+// pkg/front_end/testcases/regress/issue_29982.dart:7:17: Error: Expected ']' before this.
+//   print('${eh[éh']}');
+//                 ^^^^
+//
+// pkg/front_end/testcases/regress/issue_29982.dart:7:15: Error: Undefined name 'éh'.
+//   print('${eh[éh']}');
+//               ^^
+//
+// pkg/front_end/testcases/regress/issue_29982.dart:7:17: Error: Expected '}' before this.
+//   print('${eh[éh']}');
+//                 ^^^^
+//
+// pkg/front_end/testcases/regress/issue_29982.dart:7:21: Error: Expected a String, but got ')'.
+//   print('${eh[éh']}');
+//                     ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::Map<core::String*, core::String*>* eh = <core::String*, core::String*>{"\u0233h": "\u0233h"};
+  core::print("${eh.{core::Map::[]}(invalid-expression "pkg/front_end/testcases/regress/issue_29982.dart:7:15: Error: Undefined name '\u0233h'.
+  print('\${eh[\u0233h']}');
+              ^^"){(core::Object*) →* core::String*}}");
+}
diff --git a/pkg/front_end/testcases/regress/issue_29983.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29983.dart.weak.modular.expect
new file mode 100644
index 0000000..990d69c
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29983.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29983.dart:7:10: Error: Undefined name 'missing'.
+//   return missing;
+//          ^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_29983.dart:7:3: Error: 'sync*' and 'async*' can't return a value.
+//   return missing;
+//   ^
+//
+// pkg/front_end/testcases/regress/issue_29983.dart:11:14: Error: Undefined name 'dummy'.
+// g() sync* => dummy;
+//              ^^^^^
+//
+// pkg/front_end/testcases/regress/issue_29983.dart:11:14: Error: 'sync*' and 'async*' can't return a value.
+// g() sync* => dummy;
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method f() → dynamic sync* {
+  invalid-expression "pkg/front_end/testcases/regress/issue_29983.dart:7:3: Error: 'sync*' and 'async*' can't return a value.
+  return missing;
+  ^";
+}
+static method g() → dynamic sync* 
+  invalid-expression "pkg/front_end/testcases/regress/issue_29983.dart:11:14: Error: 'sync*' and 'async*' can't return a value.
+g() sync* => dummy;
+             ^";
+static method h() → dynamic sync* {
+  (() → core::String* => "return")(){() →* core::String*};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_29984.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29984.dart.weak.modular.expect
new file mode 100644
index 0000000..0c71c56
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29984.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29984.dart:6:16: Error: Undefined name 'i'.
+//   for (int i = i;; false) {}
+//                ^
+//
+// pkg/front_end/testcases/regress/issue_29984.dart:6:12: Error: Can't declare 'i' because it was already used in this scope.
+//   for (int i = i;; false) {}
+//            ^
+// pkg/front_end/testcases/regress/issue_29984.dart:6:16: Context: Previous use of 'i'.
+//   for (int i = i;; false) {}
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method bad() → dynamic {
+  for (core::int* i = invalid-expression "pkg/front_end/testcases/regress/issue_29984.dart:6:12: Error: Can't declare 'i' because it was already used in this scope.
+  for (int i = i;; false) {}
+           ^" in invalid-expression "pkg/front_end/testcases/regress/issue_29984.dart:6:16: Error: Undefined name 'i'.
+  for (int i = i;; false) {}
+               ^"; ; false) {
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_29985.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29985.dart.weak.modular.expect
new file mode 100644
index 0000000..ca444a5
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29985.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29985.dart:6:3: Error: The non-ASCII character '🔛' (U+1F51B) can't be used in identifiers, only in strings and comments.
+// Try using an US-ASCII letter, a digit, '_' (an underscore), or '$' (a dollar sign).
+//   🔛
+//   ^
+//
+// pkg/front_end/testcases/regress/issue_29985.dart:6:3: Error: Expected ';' after this.
+//   🔛
+//   ^^
+//
+// pkg/front_end/testcases/regress/issue_29985.dart:6:3: Error: Undefined name '🔛'.
+//   🔛
+//   ^^
+//
+import self as self;
+
+static method bad() → dynamic {
+  invalid-expression "pkg/front_end/testcases/regress/issue_29985.dart:6:3: Error: Undefined name '\u55357\u56603'.
+  \u55357\u56603
+  ^^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_29986.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29986.dart.weak.modular.expect
new file mode 100644
index 0000000..f0b03d5
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29986.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29986.dart:8:13: Error: Expected a function body or '=>'.
+// Try adding {}.
+// C(this.name);
+//             ^
+//
+// pkg/front_end/testcases/regress/issue_29986.dart:8:3: Error: Field formal parameters can only be used in a constructor.
+// Try removing 'this.'.
+// C(this.name);
+//   ^^^^
+//
+import self as self;
+
+static method main() → dynamic {}
+static abstract method C(dynamic name) → dynamic;
diff --git a/pkg/front_end/testcases/regress/issue_29987.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_29987.dart.weak.modular.expect
new file mode 100644
index 0000000..bd49b16
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_29987.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29987.dart:5:13: Error: Couldn't parse URI 'dart_:core':
+//   Illegal scheme character.
+// import "dart_:core";
+//             ^
+//
+import self as self;
+
+import "org-dartlang-malformed-uri:?dart_%3Acore";
+
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_29987.dart:5:8: Error: Expected a URI.
+// import "dart_:core";
+//        ^
+//
+import self as self2;
diff --git a/pkg/front_end/testcases/regress/issue_30834.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_30834.dart.weak.modular.expect
new file mode 100644
index 0000000..6f89ffe
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_30834.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_30834.dart:6:7: Error: A class member can't have the same name as the enclosing class.
+// Try renaming the member.
+//   set A(v) {}
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  set A(dynamic v) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::A* a = new self::A::•();
+  a.{self::A::A} = 5;
+}
diff --git a/pkg/front_end/testcases/regress/issue_30836.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_30836.dart.weak.modular.expect
new file mode 100644
index 0000000..422b26c
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_30836.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_30836.dart:6:13: Error: Final field 'x' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int x;
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  final field core::int* x = null;
+  constructor •() → self::A*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/regress/issue_30838.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_30838.dart.weak.modular.expect
new file mode 100644
index 0000000..f1431a1
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_30838.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef Foo<S extends core::Object* = dynamic> = <T extends core::Object* = dynamic>(T*) →* S*;
+class A extends core::Object {
+  field <T extends core::Object* = dynamic>(T*) →* core::int* f = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method test() → void {
+    let final core::String* #t1 = "hello" in this.{self::A::f}{<T extends core::Object* = dynamic>(T*) →* core::int*}<core::String*>(#t1){(core::String*) →* core::int*};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo<T extends core::Object* = dynamic>(self::foo::T* x) → core::int*
+  return 3;
+static method bar() → <T extends core::Object* = dynamic>(T*) →* core::int*
+  return #C1;
+static method test1() → void {
+  self::bar()<core::String*>("hello"){(core::String*) →* core::int*};
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::foo
+}
diff --git a/pkg/front_end/testcases/regress/issue_30981.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_30981.dart.weak.modular.expect
new file mode 100644
index 0000000..c413ee9
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_30981.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_30981.dart:6:7: Error: A class member can't have the same name as the enclosing class.
+// Try renaming the member.
+//   get A {
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  get A() → dynamic {
+    core::print("Actually, I'm a getter, not a constructor.");
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::A::•();
+}
diff --git a/pkg/front_end/testcases/regress/issue_30994.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_30994.dart.weak.modular.expect
new file mode 100644
index 0000000..23676b0
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_30994.dart.weak.modular.expect
@@ -0,0 +1,118 @@
+library lib;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_30994.dart:6:7: Error: Can't use string interpolation in a URI.
+// part '$foo';
+//       ^
+//
+// pkg/front_end/testcases/regress/issue_30994.dart:7:7: Error: Can't use string interpolation in a URI.
+// part '$foo/bar';
+//       ^
+//
+// pkg/front_end/testcases/regress/issue_30994.dart:8:7: Error: Can't use string interpolation in a URI.
+// part '$for/bar';
+//       ^
+//
+// pkg/front_end/testcases/regress/issue_30994.dart:9:7: Error: Can't use string interpolation in a URI.
+// part '${true}';
+//       ^
+//
+// pkg/front_end/testcases/regress/issue_30994.dart:10:10: Error: Can't use string interpolation in a URI.
+// part 'the${1}thing';
+//          ^
+//
+// pkg/front_end/testcases/regress/issue_30994.dart:11:12: Error: Can't use string interpolation in a URI.
+// part 'part_$foo${'a'}.dart';
+//            ^
+//
+// pkg/front_end/testcases/regress/issue_30994.dart:12:12: Error: Can't use string interpolation in a URI.
+// part 'part_${'a'}_$foo.dart';
+//            ^
+//
+import self as self;
+
+part org-dartlang-malformed-uri:bad247;
+part org-dartlang-malformed-uri:bad260;
+part org-dartlang-malformed-uri:bad277;
+part org-dartlang-malformed-uri:bad294;
+part org-dartlang-malformed-uri:bad310;
+part org-dartlang-malformed-uri:bad331;
+part org-dartlang-malformed-uri:bad360;
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_30994.dart:6:6: Error: Expected a URI.
+// part '$foo';
+//      ^
+//
+import self as self2;
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_30994.dart:7:6: Error: Expected a URI.
+// part '$foo/bar';
+//      ^
+//
+import self as self3;
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_30994.dart:8:6: Error: Expected a URI.
+// part '$for/bar';
+//      ^
+//
+import self as self4;
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_30994.dart:9:6: Error: Expected a URI.
+// part '${true}';
+//      ^
+//
+import self as self5;
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_30994.dart:10:6: Error: Expected a URI.
+// part 'the${1}thing';
+//      ^
+//
+import self as self6;
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_30994.dart:11:6: Error: Expected a URI.
+// part 'part_$foo${'a'}.dart';
+//      ^
+//
+import self as self7;
+
+
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_30994.dart:12:6: Error: Expected a URI.
+// part 'part_${'a'}_$foo.dart';
+//      ^
+//
+import self as self8;
diff --git a/pkg/front_end/testcases/regress/issue_31155.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31155.dart.weak.modular.expect
new file mode 100644
index 0000000..2f83d69
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31155.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_31155.dart:11:11: Error: A map literal can't be prefixed by 'Map'.
+// Try removing 'Map'
+//   var f = Map<A, B> {};
+//           ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  field core::Map<self::A*, self::B*>* f = <self::A*, self::B*>{};
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/regress/issue_31157.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31157.dart.weak.modular.expect
new file mode 100644
index 0000000..f999813
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31157.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_31157.dart:6:16: Error: Expected an identifier, but got '('.
+// Try inserting an identifier before '('.
+//   return null?.(1);
+//                ^
+//
+import self as self;
+
+static method bad() → dynamic {
+  return invalid-expression "pkg/front_end/testcases/regress/issue_31157.dart:6:16: Error: Expected an identifier, but got '('.
+Try inserting an identifier before '('.
+  return null?.(1);
+               ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_31171.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31171.dart.weak.modular.expect
new file mode 100644
index 0000000..7b520a3
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31171.dart.weak.modular.expect
@@ -0,0 +1,22 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_31171.dart:8:1: Error: Expected a type, but got 'typedef'.
+// typedef F = Map<String, dynamic> Function();
+// ^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_31171.dart:7:11: Error: Expected ';' after this.
+// typedef T =
+//           ^
+//
+// pkg/front_end/testcases/regress/issue_31171.dart:7:11: Error: Can't create typedef from non-type.
+// typedef T =
+//           ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef T = invalid-type;
+typedef F = () →* core::Map<core::String*, dynamic>*;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_31180.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31180.dart.weak.modular.expect
new file mode 100644
index 0000000..3412492
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31180.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_31180.dart:6:15: Error: Null safety features are disabled for this library.
+// Try removing the `@dart=` annotation or setting the language version to 2.12 or higher.
+//   return null?[1];
+//               ^
+// pkg/front_end/testcases/regress/issue_31180.dart:4:1: Context: This is the annotation that opts out this library from null safety features.
+// // @dart=2.9
+// ^^^^^^^^^^^^
+//
+import self as self;
+
+static method bad() → dynamic {
+  return let final dynamic #t1 = null in #t1 == null ?{dynamic} null : #t1{dynamic}.[](1);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_31181.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31181.dart.weak.modular.expect
new file mode 100644
index 0000000..20bc5b5
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31181.dart.weak.modular.expect
@@ -0,0 +1,7 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef Foo<unrelated T extends core::Object* = dynamic> = <T extends core::Object* = dynamic>(T*) →* T*;
+static field <T extends core::Object* = dynamic>(T*) →* T* x;
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_31183.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31183.dart.weak.modular.expect
new file mode 100644
index 0000000..3c62f2d
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31183.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_31183.dart:6:12: Error: Unexpected token 'unary'.
+//   operator unary- => 0;
+//            ^^^^^
+//
+// pkg/front_end/testcases/regress/issue_31183.dart:6:17: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+//   operator unary- => 0;
+//                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  operator unary-() → dynamic
+    return 0;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::C::•();
+}
diff --git a/pkg/front_end/testcases/regress/issue_31184.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31184.dart.weak.modular.expect
new file mode 100644
index 0000000..60fc8d2
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31184.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_31184.dart:6:19: Error: 'i' is already declared in this scope.
+//   for (int i = 0, i > 10; i++) {}
+//                   ^
+// pkg/front_end/testcases/regress/issue_31184.dart:6:12: Context: Previous declaration of 'i'.
+//   for (int i = 0, i > 10; i++) {}
+//            ^
+//
+// pkg/front_end/testcases/regress/issue_31184.dart:6:19: Error: Expected ';' after this.
+//   for (int i = 0, i > 10; i++) {}
+//                   ^
+//
+// pkg/front_end/testcases/regress/issue_31184.dart:6:21: Error: Expected an identifier, but got '>'.
+// Try inserting an identifier before '>'.
+//   for (int i = 0, i > 10; i++) {}
+//                     ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method bad() → dynamic {
+  for (core::int* i = 0, core::int* i = invalid-expression "pkg/front_end/testcases/regress/issue_31184.dart:6:19: Error: 'i' is already declared in this scope.
+  for (int i = 0, i > 10; i++) {}
+                  ^"; invalid-expression "pkg/front_end/testcases/regress/issue_31184.dart:6:21: Error: This couldn't be parsed.
+  for (int i = 0, i > 10; i++) {}
+                    ^"{<invalid>}.>(10); i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+  }
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_31185.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31185.dart.weak.modular.expect
new file mode 100644
index 0000000..ec82b98
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31185.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_31185.dart:8:12: Error: Expected ';' after this.
+//   return i ++ (i);
+//            ^^
+//
+// pkg/front_end/testcases/regress/issue_31185.dart:12:14: Error: Expected ';' after this.
+//   return (i) ++ (i);
+//              ^^
+//
+// pkg/front_end/testcases/regress/issue_31185.dart:12:12: Error: Can't assign to a parenthesized expression.
+//   return (i) ++ (i);
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field core::int* i = 5;
+static method test1() → core::int* {
+  return let final core::int* #t1 = self::i in let final core::int* #t2 = self::i = #t1.{core::num::+}(1){(core::num*) →* core::int*} in #t1;
+  self::i;
+}
+static method test2() → core::int* {
+  return invalid-expression "pkg/front_end/testcases/regress/issue_31185.dart:12:12: Error: Can't assign to a parenthesized expression.
+  return (i) ++ (i);
+           ^";
+  self::i;
+}
+static method main() → dynamic {
+  self::test1();
+}
diff --git a/pkg/front_end/testcases/regress/issue_31186.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31186.dart.weak.modular.expect
new file mode 100644
index 0000000..ce4b4c6
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31186.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_31186.dart:6:16: Error: Expected an identifier, but got 'true'.
+// Try inserting an identifier before 'true'.
+//   return null?.true;
+//                ^^^^
+//
+import self as self;
+
+static method bad() → dynamic {
+  return invalid-expression "pkg/front_end/testcases/regress/issue_31186.dart:6:16: Error: Expected an identifier, but got 'true'.
+Try inserting an identifier before 'true'.
+  return null?.true;
+               ^^^^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_31187.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31187.dart.weak.modular.expect
new file mode 100644
index 0000000..77462b2
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31187.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_31187.dart:6:16: Error: Expected an identifier, but got '1'.
+// Try inserting an identifier before '1'.
+//   return null?.1;
+//                ^
+//
+import self as self;
+
+static method bad() → dynamic {
+  return invalid-expression "pkg/front_end/testcases/regress/issue_31187.dart:6:16: Error: Expected an identifier, but got '1'.
+Try inserting an identifier before '1'.
+  return null?.1;
+               ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_31188.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31188.dart.weak.modular.expect
new file mode 100644
index 0000000..bc17959
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31188.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_31188.dart:7:18: Error: Expected ';' after this.
+// type T = Map<A, B>
+//                  ^
+//
+// pkg/front_end/testcases/regress/issue_31188.dart:7:1: Error: Type 'type' not found.
+// type T = Map<A, B>
+// ^^^^
+//
+// pkg/front_end/testcases/regress/issue_31188.dart:7:1: Error: 'type' isn't a type.
+// type T = Map<A, B>
+// ^^^^
+//
+// pkg/front_end/testcases/regress/issue_31188.dart:7:14: Error: 'A' isn't a type.
+// type T = Map<A, B>
+//              ^
+//
+// pkg/front_end/testcases/regress/issue_31188.dart:7:17: Error: 'B' isn't a type.
+// type T = Map<A, B>
+//                 ^
+//
+// pkg/front_end/testcases/regress/issue_31188.dart:7:13: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+// type T = Map<A, B>
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field invalid-type T = #C1;
+static method main() → dynamic {}
+
+constants  {
+  #C1 = TypeLiteralConstant(core::Map<dynamic, dynamic>*)
+}
diff --git a/pkg/front_end/testcases/regress/issue_31190.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31190.dart.weak.modular.expect
new file mode 100644
index 0000000..ba00133
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31190.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_31190.dart:6:3: Error: Can't use type arguments with type variable 'T'.
+// Try removing the type arguments.
+//   T<U> v;
+//   ^
+//
+// pkg/front_end/testcases/regress/issue_31190.dart:6:5: Error: Type 'U' not found.
+//   T<U> v;
+//     ^
+//
+// pkg/front_end/testcases/regress/issue_31190.dart:6:5: Error: 'U' isn't a type.
+//   T<U> v;
+//     ^
+//
+// pkg/front_end/testcases/regress/issue_31190.dart:6:3: Error: Expected 0 type arguments.
+//   T<U> v;
+//   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Typed<T extends core::Object* = dynamic> extends core::Object {
+  field invalid-type v = null;
+  synthetic constructor •() → self::Typed<self::Typed::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_31192.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31192.dart.weak.modular.expect
new file mode 100644
index 0000000..0640c28
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31192.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_31192.dart:7:17: Error: Expected an assignment after the field name.
+// To initialize a field, use the syntax 'name = value'.
+//   Increment() : x++ {}
+//                 ^
+//
+// pkg/front_end/testcases/regress/issue_31192.dart:7:17: Error: Can't access 'this' in a field initializer to read 'x'.
+//   Increment() : x++ {}
+//                 ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Increment extends core::Object {
+  field core::int* x = null;
+  constructor •() → self::Increment*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/regress/issue_31192.dart:7:17: Error: This couldn't be parsed.
+  Increment() : x++ {}
+                ^" {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_31198.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31198.dart.weak.modular.expect
new file mode 100644
index 0000000..ecfe034
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31198.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_31198.dart:10:24: Error: Expected an identifier, but got ')'.
+// Try inserting an identifier before ')'.
+//   B.named2(): super().() {}
+//                        ^
+//
+// pkg/front_end/testcases/regress/issue_31198.dart:8:8: Error: Can't use 'super' as an expression.
+// To delegate a constructor to a super constructor, put the super call as an initializer.
+//   B(): super().foo() {}
+//        ^
+//
+// pkg/front_end/testcases/regress/issue_31198.dart:8:16: Error: Expected an initializer.
+//   B(): super().foo() {}
+//                ^
+//
+// pkg/front_end/testcases/regress/issue_31198.dart:9:23: Error: Expected identifier, but got 'super'.
+//   B.named1(): super().super() {}
+//                       ^^^^^
+//
+// pkg/front_end/testcases/regress/issue_31198.dart:10:23: Error: Expected an identifier, but got '('.
+// Try inserting an identifier before '('.
+//   B.named2(): super().() {}
+//                       ^
+//
+// pkg/front_end/testcases/regress/issue_31198.dart:10:23: Error: Expected an initializer.
+//   B.named2(): super().() {}
+//                       ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  constructor •() → self::B*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/regress/issue_31198.dart:8:8: Error: Can't use 'super' as an expression.
+To delegate a constructor to a super constructor, put the super call as an initializer.
+  B(): super().foo() {}
+       ^"{dynamic}.foo() {}
+  constructor named1() → self::B*
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/regress/issue_31198.dart:9:23: Error: Expected identifier, but got 'super'.
+  B.named1(): super().super() {}
+                      ^^^^^" {}
+  constructor named2() → self::B*
+    : final dynamic #t3 = invalid-expression "pkg/front_end/testcases/regress/issue_31198.dart:10:23: Error: Expected an identifier, but got '('.
+Try inserting an identifier before '('.
+  B.named2(): super().() {}
+                      ^" {}
+}
+static method bad() → dynamic {
+  new self::B::•();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_31213.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31213.dart.weak.modular.expect
new file mode 100644
index 0000000..59e271c
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31213.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+typedef C<contravariant A extends core::Object* = dynamic, contravariant K extends core::Object* = dynamic> = <B extends core::Object* = dynamic>(A*, K*, B*) →* core::int*;
+typedef D<contravariant K extends core::Object* = dynamic> = <A extends core::Object* = dynamic>(core::int*) →* <B extends core::Object* = dynamic>(A*, K*, B*) →* core::int*;
+static method producer<K extends core::Object* = dynamic>() → dynamic {
+  return <A extends core::Object* = dynamic>(core::int* v1) → <B extends core::Object* = dynamic>(A*, self::producer::K*, B*) →* core::int* {
+    return <B extends core::Object* = dynamic>(A* v2, self::producer::K* v3, B* v4) → core::int* => 0;
+  };
+}
+static method main() → dynamic {
+  assert(self::producer<core::String*>() is <A extends core::Object* = dynamic>(core::int*) →* <B extends core::Object* = dynamic>(A*, core::String*, B*) →* core::int*);
+}
diff --git a/pkg/front_end/testcases/regress/issue_31299.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31299.dart.weak.modular.expect
new file mode 100644
index 0000000..c1f0dcb
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31299.dart.weak.modular.expect
@@ -0,0 +1,52 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_31299.dart:18:12: Error: Too many positional arguments: 0 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//   new A.foo(1, 2);
+//            ^
+// pkg/front_end/testcases/regress/issue_31299.dart:10:3: Context: Found this candidate, but the arguments don't match.
+//   A.foo() : m = 2;
+//   ^^^^^
+//
+// pkg/front_end/testcases/regress/issue_31299.dart:15:14: Error: Too few positional arguments: 2 required, 0 given.
+//   new A().foo();
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* m;
+  constructor •() → self::A*
+    : self::A::m = 1, super core::Object::•()
+    ;
+  constructor foo() → self::A*
+    : self::A::m = 2, super core::Object::•()
+    ;
+  method foo(core::int* a, core::int* b) → core::int*
+    return a.{core::num::+}(b.{core::num::*}(this.{self::A::m}{core::int*}){(core::num*) →* core::int*}){(core::num*) →* core::int*};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/regress/issue_31299.dart:15:14: Error: Too few positional arguments: 2 required, 0 given.
+  new A().foo();
+             ^" in new self::A::•().{self::A::foo}{<inapplicable>}.(){() →* invalid-type};
+  new self::A::•().{self::A::foo}(1, 2){(core::int*, core::int*) →* core::int*};
+  new self::A::foo();
+  invalid-expression "pkg/front_end/testcases/regress/issue_31299.dart:18:12: Error: Too many positional arguments: 0 allowed, but 2 found.
+Try removing the extra positional arguments.
+  new A.foo(1, 2);
+           ^";
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_31766.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31766.dart.weak.modular.expect
new file mode 100644
index 0000000..ec4557f
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31766.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method foo() → dynamic
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  function bar<T extends self::A*>(T* t) → void {
+    core::print("t.foo()=${t.{self::A::foo}(){() →* dynamic}}");
+  }
+  bar<self::A*>(new self::A::•()){(self::A*) →* void};
+  (<S extends self::A*>(S* s) → Null {
+    core::print("s.foo()=${s.{self::A::foo}(){() →* dynamic}}");
+  })<self::A*>(new self::A::•()){(self::A*) →* Null};
+}
diff --git a/pkg/front_end/testcases/regress/issue_31846.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31846.dart.weak.modular.expect
new file mode 100644
index 0000000..a893a8d
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31846.dart.weak.modular.expect
@@ -0,0 +1,17 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::print(#C1 is () →* dynamic);
+  core::print((<T extends core::Object* = dynamic>(T* x) → T* => x).{core::Object::runtimeType}{core::Type*});
+  core::print((<T extends core::num*>(T* x) → T* => x).{core::Object::runtimeType}{core::Type*});
+  core::print((<T extends core::Comparable<T*>* = core::Comparable<dynamic>*>(T* x) → T* => x).{core::Object::runtimeType}{core::Type*});
+  core::print((<T extends core::Comparable<S*>* = core::Comparable<dynamic>*, S extends core::Object* = dynamic>(T* x) → T* => x).{core::Object::runtimeType}{core::Type*});
+  core::print((<T extends (T*) →* dynamic = (Null) →* dynamic>(T* x) → T* => x).{core::Object::runtimeType}{core::Type*});
+  core::print((<T extends core::List<core::List<T*>*>* = core::List<core::List<dynamic>*>*>(T* x) → T* => x).{core::Object::runtimeType}{core::Type*});
+}
+
+constants  {
+  #C1 = static-tearoff self::main
+}
diff --git a/pkg/front_end/testcases/regress/issue_31996.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_31996.dart.weak.modular.expect
new file mode 100644
index 0000000..6cf6fb4
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_31996.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+abstract class B<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Base extends core::Object implements self::B<dynamic> {
+  synthetic constructor •() → self::Base*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Child1 extends self::Base implements self::C<core::int*> {
+  synthetic constructor •() → self::Child1*
+    : super self::Base::•()
+    ;
+}
+class Child2 extends self::Base implements self::C<core::double*> {
+  synthetic constructor •() → self::Child2*
+    : super self::Base::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_32182.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_32182.dart.weak.modular.expect
new file mode 100644
index 0000000..3b90e8d
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_32182.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue_32182.dart" as self;
+
+class A<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M extends core::Object {
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  method m() → dynamic
+    return 42;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _C&A&M = self::A<self::A<dynamic>*> with self::M /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_C&A&M*
+    : super self::A::•()
+    ;
+  mixin-super-stub method m() → dynamic
+    return super.{self::M::m}();
+}
+class C extends self::_C&A&M {
+  synthetic constructor •() → self::C*
+    : super self::_C&A&M::•()
+    ;
+}
+static method main() → dynamic {
+  new self::C::•().{self::_C&A&M::m}(){() →* dynamic}{dynamic}.+(1);
+}
diff --git a/pkg/front_end/testcases/regress/issue_32196.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_32196.dart.weak.modular.expect
new file mode 100644
index 0000000..d1c71d6
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_32196.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  final field core::String* name;
+  constructor get(core::String* name) → self::A*
+    : self::A::name = name, super core::Object::•()
+    ;
+  constructor set(core::String* name) → self::A*
+    : self::A::name = name, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::A::get("get");
+  new self::A::set("set");
+}
diff --git a/pkg/front_end/testcases/regress/issue_32200.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_32200.dart.weak.modular.expect
new file mode 100644
index 0000000..d70c7d0
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_32200.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_32200.dart:8:3: Error: 'self.Foo' can't be used as a type because 'self' doesn't refer to an import prefix.
+//   self.Foo self;
+//   ^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue_32200.dart" as self;
+
+class Foo extends core::Object {
+  field invalid-type self = null;
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::Foo* instance = new self::Foo::•();
+  instance.{self::Foo::self} = instance;
+}
diff --git a/pkg/front_end/testcases/regress/issue_32660.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_32660.dart.weak.modular.expect
new file mode 100644
index 0000000..ec03c53
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_32660.dart.weak.modular.expect
@@ -0,0 +1,106 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_32660.dart:13:7: Error: The implementation of 'foo' in the non-abstract class 'C' does not conform to its interface.
+// class C extends A implements B {
+//       ^
+// pkg/front_end/testcases/regress/issue_32660.dart:6:3: Context: The method 'A.foo' has fewer named arguments than those of overridden method 'B.foo'.
+//   foo(int x) => x;
+//   ^
+// pkg/front_end/testcases/regress/issue_32660.dart:10:3: Context: This is the overridden method ('foo').
+//   foo(int x, {int y}) => y;
+//   ^
+//
+// pkg/front_end/testcases/regress/issue_32660.dart:24:7: Error: The implementation of 'foo' in the non-abstract class 'E' does not conform to its interface.
+// class E extends D {
+//       ^
+// pkg/front_end/testcases/regress/issue_32660.dart:21:3: Context: The method 'D.foo' has fewer named arguments than those of overridden method 'E.foo'.
+//   foo(int x) => x;
+//   ^
+// pkg/front_end/testcases/regress/issue_32660.dart:25:3: Context: This is the overridden method ('foo').
+//   foo(int x, {int y});
+//   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method foo(core::int* x) → dynamic
+    return x;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method foo(core::int* x, {core::int* y = #C1}) → dynamic
+    return y;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::A implements self::B {
+  synthetic constructor •() → self::C*
+    : super self::A::•()
+    ;
+  method noSuchMethod(core::Invocation* i) → dynamic {
+    core::print("No such method!");
+    return 42;
+  }
+  abstract member-signature method foo(core::int* x, {core::int* y = #C1}) → dynamic; -> self::B::foo
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  method foo(core::int* x) → dynamic
+    return x;
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E extends self::D {
+  synthetic constructor •() → self::E*
+    : super self::D::•()
+    ;
+  abstract method foo(core::int* x, {core::int* y = #C1}) → dynamic;
+  method noSuchMethod(core::Invocation* i) → dynamic {
+    core::print(i.{core::Invocation::namedArguments}{core::Map<core::Symbol*, dynamic>*});
+    return 42;
+  }
+}
+static method main() → dynamic {
+  self::C* c = new self::C::•();
+  self::E* e = new self::E::•();
+}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/regress/issue_32972.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_32972.dart.weak.modular.expect
new file mode 100644
index 0000000..660b650
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_32972.dart.weak.modular.expect
@@ -0,0 +1,90 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_32972.dart:22:3: Error: Expected 1 type arguments.
+//   foo<String, String>("hello world");
+//   ^
+// pkg/front_end/testcases/regress/issue_32972.dart:5:6: Context: Found this candidate, but the arguments don't match.
+// void foo<X>(X i) {
+//      ^^^
+//
+// pkg/front_end/testcases/regress/issue_32972.dart:24:7: Error: Expected 1 type arguments.
+//   Foo.foo<int, int>(42);
+//       ^
+// pkg/front_end/testcases/regress/issue_32972.dart:10:10: Context: Found this candidate, but the arguments don't match.
+//   static foo<X>(X i) {
+//          ^^^
+//
+// pkg/front_end/testcases/regress/issue_32972.dart:29:7: Error: Expected 2 type arguments.
+//   new Bar<String>();
+//       ^
+// pkg/front_end/testcases/regress/issue_32972.dart:19:7: Context: The class 'Bar' has a constructor that takes no arguments.
+// class Bar<X, Y> {}
+//       ^
+//
+// pkg/front_end/testcases/regress/issue_32972.dart:27:5: Error: Expected 1 type arguments.
+//   f.bar<double, double>(42.42);
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Foo extends core::Object {
+  synthetic constructor •() → self::Foo*
+    : super core::Object::•()
+    ;
+  static method foo<X extends core::Object* = dynamic>(self::Foo::foo::X* i) → dynamic {
+    core::print(i);
+  }
+  method bar<X extends core::Object* = dynamic>(self::Foo::bar::X* i) → dynamic {
+    core::print(i);
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class Bar<X extends core::Object* = dynamic, Y extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::Bar<self::Bar::X*, self::Bar::Y*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo<X extends core::Object* = dynamic>(self::foo::X* i) → void {
+  core::print(i);
+}
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/regress/issue_32972.dart:22:3: Error: Expected 1 type arguments.
+  foo<String, String>(\"hello world\");
+  ^";
+  self::foo<core::String*>("hello world");
+  invalid-expression "pkg/front_end/testcases/regress/issue_32972.dart:24:7: Error: Expected 1 type arguments.
+  Foo.foo<int, int>(42);
+      ^";
+  self::Foo::foo<core::int*>(42);
+  self::Foo* f = new self::Foo::•();
+  invalid-expression "pkg/front_end/testcases/regress/issue_32972.dart:27:5: Error: Expected 1 type arguments.
+  f.bar<double, double>(42.42);
+    ^" in f.{self::Foo::bar}{<inapplicable>}.<core::double*, core::double*>(42.42){(invalid-type) →* invalid-type};
+  f.{self::Foo::bar}<core::double*>(42.42){(core::double*) →* dynamic};
+  invalid-expression "pkg/front_end/testcases/regress/issue_32972.dart:29:7: Error: Expected 2 type arguments.
+  new Bar<String>();
+      ^";
+  new self::Bar::•<core::String*, core::String*>();
+}
diff --git a/pkg/front_end/testcases/regress/issue_33452.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_33452.dart.weak.modular.expect
new file mode 100644
index 0000000..0f3ef8d
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_33452.dart.weak.modular.expect
@@ -0,0 +1,66 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_33452.dart:10:29: Error: Couldn't find constructor 'ExistingClass.nonExistingConstructor'.
+//   var x = new ExistingClass.nonExistingConstructor();
+//                             ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_33452.dart:11:11: Error: Couldn't find constructor 'ExistingClass'.
+//   x = new ExistingClass();
+//           ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_33452.dart:12:11: Error: Couldn't find constructor 'ExistingClass'.
+//   x = new ExistingClass<String>();
+//           ^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_33452.dart:13:33: Error: Couldn't find constructor 'ExistingClass.nonExistingConstructor'.
+//   x = new ExistingClass<String>.nonExistingConstructor();
+//                                 ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_33452.dart:14:41: Error: Couldn't find constructor 'ExistingClass.nonExistingConstructor'.
+//   x = new ExistingClass<String, String>.nonExistingConstructor();
+//                                         ^^^^^^^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_33452.dart:15:11: Error: Couldn't find constructor 'NonExistingClass'.
+//   x = new NonExistingClass();
+//           ^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class ExistingClass extends core::Object {
+  constructor existingConstructor() → self::ExistingClass*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  invalid-type x = invalid-expression "pkg/front_end/testcases/regress/issue_33452.dart:10:29: Error: Couldn't find constructor 'ExistingClass.nonExistingConstructor'.
+  var x = new ExistingClass.nonExistingConstructor();
+                            ^^^^^^^^^^^^^^^^^^^^^^";
+  x = invalid-expression "pkg/front_end/testcases/regress/issue_33452.dart:11:11: Error: Couldn't find constructor 'ExistingClass'.
+  x = new ExistingClass();
+          ^^^^^^^^^^^^^";
+  x = invalid-expression "pkg/front_end/testcases/regress/issue_33452.dart:12:11: Error: Couldn't find constructor 'ExistingClass'.
+  x = new ExistingClass<String>();
+          ^^^^^^^^^^^^^";
+  x = invalid-expression "pkg/front_end/testcases/regress/issue_33452.dart:13:33: Error: Couldn't find constructor 'ExistingClass.nonExistingConstructor'.
+  x = new ExistingClass<String>.nonExistingConstructor();
+                                ^^^^^^^^^^^^^^^^^^^^^^";
+  x = invalid-expression "pkg/front_end/testcases/regress/issue_33452.dart:14:41: Error: Couldn't find constructor 'ExistingClass.nonExistingConstructor'.
+  x = new ExistingClass<String, String>.nonExistingConstructor();
+                                        ^^^^^^^^^^^^^^^^^^^^^^";
+  x = invalid-expression "pkg/front_end/testcases/regress/issue_33452.dart:15:11: Error: Couldn't find constructor 'NonExistingClass'.
+  x = new NonExistingClass();
+          ^^^^^^^^^^^^^^^^";
+}
diff --git a/pkg/front_end/testcases/regress/issue_33672.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_33672.dart.weak.modular.expect
new file mode 100644
index 0000000..7caa5cb
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_33672.dart.weak.modular.expect
@@ -0,0 +1,18 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::int* count = 0;
+  #L1:
+  for (core::int* a = 0; a.{core::num::<}(10){(core::num*) →* core::bool*}; a = a.{core::num::+}(1){(core::num*) →* core::int*}) {
+    for (core::int* b = 0; b.{core::num::<}(10){(core::num*) →* core::bool*}; b = b.{core::num::+}(1){(core::num*) →* core::int*}) {
+      count = count.{core::num::+}(1){(core::num*) →* core::int*};
+      if(count =={core::num::==}{(core::Object*) →* core::bool*} 27)
+        break #L1;
+    }
+    count = count.{core::num::+}(1){(core::num*) →* core::int*};
+  }
+  if(!(count =={core::num::==}{(core::Object*) →* core::bool*} 27))
+    throw "failed: ${count}";
+}
diff --git a/pkg/front_end/testcases/regress/issue_34225.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_34225.dart.weak.modular.expect
new file mode 100644
index 0000000..2a92ec9
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_34225.dart.weak.modular.expect
@@ -0,0 +1,65 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_34225.dart:6:14: Error: A class member can't have the same name as the enclosing class.
+// Try renaming the member.
+//   static set C(v) {} //# 01: compile-time error
+//              ^
+//
+// pkg/front_end/testcases/regress/issue_34225.dart:10:7: Error: A class member can't have the same name as the enclosing class.
+// Try renaming the member.
+//   set D(v) {} //# 02: compile-time error
+//       ^
+//
+// pkg/front_end/testcases/regress/issue_34225.dart:15:5: Error: The setter 'C' isn't defined for the class 'C'.
+//  - 'C' is from 'pkg/front_end/testcases/regress/issue_34225.dart'.
+// Try correcting the name to the name of an existing setter, or defining a setter or field named 'C'.
+//   c.C = 5;
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  static set C(dynamic v) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends core::Object {
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  set D(dynamic v) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C* c = new self::C::•();
+  invalid-expression "pkg/front_end/testcases/regress/issue_34225.dart:15:5: Error: The setter 'C' isn't defined for the class 'C'.
+ - 'C' is from 'pkg/front_end/testcases/regress/issue_34225.dart'.
+Try correcting the name to the name of an existing setter, or defining a setter or field named 'C'.
+  c.C = 5;
+    ^" in c{<unresolved>}.C = 5;
+  self::D* d = new self::D::•();
+  d.{self::D::D} = 5;
+}
diff --git a/pkg/front_end/testcases/regress/issue_34291.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_34291.dart.weak.modular.expect
new file mode 100644
index 0000000..efb5579
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_34291.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_34291.dart:9:1: Error: Expected 0 type arguments.
+// lib.A<B> foo() {}
+// ^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue_34291_lib.dart" as lib;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method foo() → invalid-type {}
+static method main() → dynamic {}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self2::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/regress/issue_34403.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_34403.dart.weak.modular.expect
new file mode 100644
index 0000000..cb1b2fd
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_34403.dart.weak.modular.expect
@@ -0,0 +1,216 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:16:14: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   var c1 = C.bar<int>();
+//              ^^^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:18:18: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   var c2 = new C.bar<int>();
+//                  ^^^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:20:13: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   var c3 = C<String>.bar<int>();
+//             ^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:20:22: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   var c3 = C<String>.bar<int>();
+//                      ^^^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:22:26: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   var c4 = new C<String>.bar<int>();
+//                          ^^^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:25:16: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   const d1 = D.foo<int>();
+//                ^^^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:27:22: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   const d2 = const D.foo<int>();
+//                      ^^^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:29:15: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   const d3 = D<String>.foo<int>();
+//               ^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:29:24: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   const d3 = D<String>.foo<int>();
+//                        ^^^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:31:30: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   const d4 = const D<String>.foo<int>();
+//                              ^^^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:34:16: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   var e1 = p.E.bar<int>();
+//                ^^^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:36:20: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   var e2 = new p.E.bar<int>();
+//                    ^^^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:38:15: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   var e3 = p.E<String>.bar<int>();
+//               ^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:38:24: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   var e3 = p.E<String>.bar<int>();
+//                        ^^^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:40:28: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   var e4 = new p.E<String>.bar<int>();
+//                            ^^^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:43:18: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   const f1 = p.F.foo<int>();
+//                  ^^^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:45:24: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   const f2 = const p.F.foo<int>();
+//                        ^^^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:47:17: Error: This requires the 'constructor-tearoffs' language feature to be enabled.
+// Try updating your pubspec.yaml to set the minimum SDK constraint to 2.15 or higher, and running 'pub get'.
+//   const f3 = p.F<String>.foo<int>();
+//                 ^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:47:26: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   const f3 = p.F<String>.foo<int>();
+//                          ^^^
+//
+// pkg/front_end/testcases/regress/issue_34403.dart:49:32: Error: A constructor invocation can't have type arguments after the constructor name.
+// Try removing the type arguments or placing them after the class name.
+//   const f4 = const p.F<String>.foo<int>();
+//                                ^^^
+//
+import self as self;
+import "dart:core" as core;
+import "issue_34403_lib.dart" as iss;
+
+import "org-dartlang-testcase:///issue_34403_lib.dart" as p;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  constructor bar() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<T extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const constructor foo() → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C<core::int*>* c1 = new self::C::bar<core::int*>();
+  c1.{self::C::toString}(){() →* core::String*};
+  self::C<core::int*>* c2 = new self::C::bar<core::int*>();
+  c2.{self::C::toString}(){() →* core::String*};
+  self::C<core::int*>* c3 = new self::C::bar<core::int*>();
+  c3.{self::C::toString}(){() →* core::String*};
+  self::C<core::String*>* c4 = new self::C::bar<core::String*>();
+  c4.{self::C::toString}(){() →* core::String*};
+  #C1.{self::D::toString}(){() →* core::String*};
+  #C1.{self::D::toString}(){() →* core::String*};
+  #C1.{self::D::toString}(){() →* core::String*};
+  #C2.{self::D::toString}(){() →* core::String*};
+  iss::E<core::int*>* e1 = new iss::E::bar<core::int*>();
+  e1.{iss::E::toString}(){() →* core::String*};
+  iss::E<dynamic>* e2 = new iss::E::bar<dynamic>();
+  e2.{iss::E::toString}(){() →* core::String*};
+  iss::E<core::int*>* e3 = new iss::E::bar<core::int*>();
+  e3.{iss::E::toString}(){() →* core::String*};
+  iss::E<core::String*>* e4 = new iss::E::bar<core::String*>();
+  e4.{iss::E::toString}(){() →* core::String*};
+  #C3.{iss::F::toString}(){() →* core::String*};
+  #C4.{iss::F::toString}(){() →* core::String*};
+  #C3.{iss::F::toString}(){() →* core::String*};
+  #C5.{iss::F::toString}(){() →* core::String*};
+}
+
+library;
+import self as iss;
+import "dart:core" as core;
+
+class E<T extends core::Object* = dynamic> extends core::Object {
+  constructor bar() → iss::E<iss::E::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class F<T extends core::Object* = dynamic> extends core::Object /*hasConstConstructor*/  {
+  const constructor foo() → iss::F<iss::F::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+
+constants  {
+  #C1 = self::D<core::int*> {}
+  #C2 = self::D<core::String*> {}
+  #C3 = iss::F<core::int*> {}
+  #C4 = iss::F<dynamic> {}
+  #C5 = iss::F<core::String*> {}
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///issue_34403.dart:
+- D.foo (from org-dartlang-testcase:///issue_34403.dart:12:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+- F.foo (from org-dartlang-testcase:///issue_34403_lib.dart:10:9)
diff --git a/pkg/front_end/testcases/regress/issue_34498.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_34498.dart.weak.modular.expect
new file mode 100644
index 0000000..fa054b4
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_34498.dart.weak.modular.expect
@@ -0,0 +1,91 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_34498.dart:8:3: Error: 'lib.MyClass' can't be used as a type because 'lib' doesn't refer to an import prefix.
+//   lib.MyClass get lib => null; // (1)
+//   ^^^^^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_34498.dart:10:3: Error: 'foo' isn't a type.
+//   foo foo() {}
+//   ^^^
+// pkg/front_end/testcases/regress/issue_34498.dart:10:7: Context: This isn't a type.
+//   foo foo() {}
+//       ^^^
+//
+// pkg/front_end/testcases/regress/issue_34498.dart:20:3: Error: Can't use type arguments with type variable 'T'.
+// Try removing the type arguments.
+//   T<String> foo() {}
+//   ^
+//
+// pkg/front_end/testcases/regress/issue_34498.dart:12:3: Error: Type 'Missing' not found.
+//   Missing bar() {}
+//   ^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue_34498_lib.dart" as lib;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  get lib() → invalid-type
+    return null;
+  method foo() → invalid-type {}
+  method bar() → invalid-type {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  synthetic constructor •() → self::B*
+    : super self::A::•()
+    ;
+}
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method foo() → invalid-type {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static final field self::A* a = null;
+static method main() → dynamic {}
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+class MyClass extends core::Object {
+  synthetic constructor •() → self2::MyClass*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/regress/issue_34563.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_34563.dart.weak.modular.expect
new file mode 100644
index 0000000..201e0fa
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_34563.dart.weak.modular.expect
@@ -0,0 +1,154 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_34563.dart:9:10: Error: Expected 'on' instead of this.
+// mixin M2 extend M1 {}
+//          ^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_34563.dart:11:10: Error: Expected 'on' instead of this.
+// mixin M3 extends M1 {}
+//          ^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_34563.dart:17:10: Error: Expected 'extends' instead of this.
+// class C2 extend C1 with M2 {}
+//          ^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_34563.dart:19:10: Error: Expected 'extends' instead of this.
+// class C3 on C1 with M3 {}
+//          ^^
+//
+// pkg/front_end/testcases/regress/issue_34563.dart:23:6: Error: The getter 'm' isn't defined for the class 'C2'.
+//  - 'C2' is from 'pkg/front_end/testcases/regress/issue_34563.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'm'.
+//   c2.m + c2.c;
+//      ^
+//
+// pkg/front_end/testcases/regress/issue_34563.dart:23:13: Error: The getter 'c' isn't defined for the class 'C2'.
+//  - 'C2' is from 'pkg/front_end/testcases/regress/issue_34563.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'c'.
+//   c2.m + c2.c;
+//             ^
+//
+// pkg/front_end/testcases/regress/issue_34563.dart:25:6: Error: The getter 'm' isn't defined for the class 'C3'.
+//  - 'C3' is from 'pkg/front_end/testcases/regress/issue_34563.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'm'.
+//   c3.m + c3.c;
+//      ^
+//
+// pkg/front_end/testcases/regress/issue_34563.dart:25:13: Error: The getter 'c' isn't defined for the class 'C3'.
+//  - 'C3' is from 'pkg/front_end/testcases/regress/issue_34563.dart'.
+// Try correcting the name to the name of an existing getter, or defining a getter or field named 'c'.
+//   c3.m + c3.c;
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+abstract class M1 extends core::Object /*isMixinDeclaration*/  {
+  get m() → core::int*
+    return 1;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M2 extends core::Object /*isMixinDeclaration*/  {
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class M3 extends core::Object /*isMixinDeclaration*/  {
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C1 extends core::Object {
+  synthetic constructor •() → self::C1*
+    : super core::Object::•()
+    ;
+  get c() → core::int*
+    return 2;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C2 extends core::Object {
+  synthetic constructor •() → self::C2*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C3 extends core::Object {
+  synthetic constructor •() → self::C3*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C2* c2 = new self::C2::•();
+  invalid-expression "pkg/front_end/testcases/regress/issue_34563.dart:23:6: Error: The getter 'm' isn't defined for the class 'C2'.
+ - 'C2' is from 'pkg/front_end/testcases/regress/issue_34563.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'm'.
+  c2.m + c2.c;
+     ^" in c2{<unresolved>}.m{dynamic}.+(invalid-expression "pkg/front_end/testcases/regress/issue_34563.dart:23:13: Error: The getter 'c' isn't defined for the class 'C2'.
+ - 'C2' is from 'pkg/front_end/testcases/regress/issue_34563.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'c'.
+  c2.m + c2.c;
+            ^" in c2{<unresolved>}.c);
+  self::C3* c3 = new self::C3::•();
+  invalid-expression "pkg/front_end/testcases/regress/issue_34563.dart:25:6: Error: The getter 'm' isn't defined for the class 'C3'.
+ - 'C3' is from 'pkg/front_end/testcases/regress/issue_34563.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'm'.
+  c3.m + c3.c;
+     ^" in c3{<unresolved>}.m{dynamic}.+(invalid-expression "pkg/front_end/testcases/regress/issue_34563.dart:25:13: Error: The getter 'c' isn't defined for the class 'C3'.
+ - 'C3' is from 'pkg/front_end/testcases/regress/issue_34563.dart'.
+Try correcting the name to the name of an existing getter, or defining a getter or field named 'c'.
+  c3.m + c3.c;
+            ^" in c3{<unresolved>}.c);
+}
diff --git a/pkg/front_end/testcases/regress/issue_34610.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_34610.dart.weak.modular.expect
new file mode 100644
index 0000000..db6cda1
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_34610.dart.weak.modular.expect
@@ -0,0 +1,109 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_34610.dart:5:15: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+// class A { get A.named => null; get bar => 1; }
+//               ^
+//
+// pkg/front_end/testcases/regress/issue_34610.dart:5:11: Error: Constructors can't be a getter.
+// Try removing 'get'.
+// class A { get A.named => null; get bar => 1; }
+//           ^^^
+//
+// pkg/front_end/testcases/regress/issue_34610.dart:7:11: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+// class B { B.named : super(); get bar => 1; }
+//           ^
+//
+// pkg/front_end/testcases/regress/issue_34610.dart:9:11: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+// class C { C.named => null; get bar => 1; }
+//           ^
+//
+// pkg/front_end/testcases/regress/issue_34610.dart:5:26: Error: Constructors can't have a return type.
+// Try removing the return type.
+// class A { get A.named => null; get bar => 1; }
+//                          ^
+//
+// pkg/front_end/testcases/regress/issue_34610.dart:9:22: Error: Constructors can't have a return type.
+// Try removing the return type.
+// class C { C.named => null; get bar => 1; }
+//                      ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  constructor named() → self::A*
+    : super core::Object::•()
+    invalid-expression "pkg/front_end/testcases/regress/issue_34610.dart:5:26: Error: Constructors can't have a return type.
+Try removing the return type.
+class A { get A.named => null; get bar => 1; }
+                         ^";
+  get bar() → dynamic
+    return 1;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object {
+  constructor named() → self::B*
+    : super core::Object::•()
+    ;
+  get bar() → dynamic
+    return 1;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  constructor named() → self::C*
+    : super core::Object::•()
+    invalid-expression "pkg/front_end/testcases/regress/issue_34610.dart:9:22: Error: Constructors can't have a return type.
+Try removing the return type.
+class C { C.named => null; get bar => 1; }
+                     ^";
+  get bar() → dynamic
+    return 1;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  try {
+    core::print(new self::A::named().{self::A::bar}{dynamic});
+    throw "expected exception";
+  }
+  on dynamic catch(final dynamic e) {
+  }
+  core::print(new self::B::named().{self::B::bar}{dynamic});
+  try {
+    core::print(new self::C::named().{self::C::bar}{dynamic});
+    throw "expected exception";
+  }
+  on dynamic catch(final dynamic e) {
+  }
+}
diff --git a/pkg/front_end/testcases/regress/issue_34614.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_34614.dart.weak.modular.expect
new file mode 100644
index 0000000..9092aae
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_34614.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_34614.dart:5:14: Error: Expected an identifier, but got '}'.
+// Try inserting an identifier before '}'.
+// class C { C. }
+//              ^
+//
+// pkg/front_end/testcases/regress/issue_34614.dart:5:11: Error: A method declaration needs an explicit list of parameters.
+// Try adding a parameter list to the method declaration.
+// class C { C. }
+//           ^
+//
+// pkg/front_end/testcases/regress/issue_34614.dart:5:14: Error: Expected '{' before this.
+// class C { C. }
+//              ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::C* c = new self::C::•();
+  c.{self::C::toString}(){() →* core::String*};
+}
diff --git a/pkg/front_end/testcases/regress/issue_34850.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_34850.dart.weak.modular.expect
new file mode 100644
index 0000000..ad3a1ce
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_34850.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_34850.dart:5:1: Error: Expected a declaration, but got '<'.
+// <foo<
+// ^
+//
+// pkg/front_end/testcases/regress/issue_34850.dart:7:1: Error: Expected '>' after this.
+// int f1() {
+// ^^^
+//
+// pkg/front_end/testcases/regress/issue_34850.dart:12:8: Error: Expected '>' after this.
+// Future<List<int>> f2() async => null;
+//        ^^^^
+//
+// pkg/front_end/testcases/regress/issue_34850.dart:12:1: Error: A function declaration needs an explicit list of parameters.
+// Try adding a parameter list to the function declaration.
+// Future<List<int>> f2() async => null;
+// ^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_34850.dart:12:19: Error: Expected '{' before this.
+// Future<List<int>> f2() async => null;
+//                   ^^
+//
+// pkg/front_end/testcases/regress/issue_34850.dart:14:13: Error: Expected a type, but got '>>'.
+// Future<List<>> f3() async {
+//             ^^
+//
+// pkg/front_end/testcases/regress/issue_34850.dart:5:2: Error: Type 'foo' not found.
+// <foo<
+//  ^^^
+//
+// pkg/front_end/testcases/regress/issue_34850.dart:5:2: Error: Expected 0 type arguments.
+// <foo<
+//  ^
+//
+// pkg/front_end/testcases/regress/issue_34850.dart:11:1: Error: Type 'foo' not found.
+// foo
+// ^^^
+//
+// pkg/front_end/testcases/regress/issue_34850.dart:14:1: Error: 'Future' isn't a type.
+// Future<List<>> f3() async {
+// ^^^^^^
+// pkg/front_end/testcases/regress/issue_34850.dart:12:1: Context: This isn't a type.
+// Future<List<int>> f2() async => null;
+// ^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_34850.dart:14:1: Error: Expected 0 type arguments.
+// Future<List<>> f3() async {
+// ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method f1() → invalid-type {
+  return null;
+}
+static method Future<List extends core::Object* = dynamic>() → invalid-type {}
+static method f2() → dynamic async 
+  return null;
+static method f3() → invalid-type async {
+  return null;
+}
+static method main() → dynamic async {
+  core::print(self::f1());
+  core::print(await self::f2());
+  core::print(await self::f3());
+}
diff --git a/pkg/front_end/testcases/regress/issue_35151.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_35151.dart.weak.modular.expect
new file mode 100644
index 0000000..146d622
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_35151.dart.weak.modular.expect
@@ -0,0 +1,74 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_35151.dart:10:15: Error: A field can only be initialized in its declaring class
+// Try passing a value into the superclass constructor, or moving the initialization into the constructor body.
+//   B() : super.a = 42;
+//               ^
+//
+// pkg/front_end/testcases/regress/issue_35151.dart:10:15: Error: Not a valid initializer.
+// To initialize a field, use the syntax 'name = value'.
+//   B() : super.a = 42;
+//               ^
+//
+// pkg/front_end/testcases/regress/issue_35151.dart:14:9: Error: Can't access 'super' in a field initializer.
+//   C() : super = 42;
+//         ^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  field core::int* a = null;
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends self::A {
+  constructor •() → self::B*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/regress/issue_35151.dart:10:15: Error: Not a valid initializer.
+To initialize a field, use the syntax 'name = value'.
+  B() : super.a = 42;
+              ^"
+    ;
+}
+class C extends core::Object {
+  constructor •() → self::C*
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/regress/issue_35151.dart:14:9: Error: Can't access 'super' in a field initializer.
+  C() : super = 42;
+        ^^^^^"
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  try {
+    self::B* b = new self::B::•();
+  }
+  on dynamic catch(final dynamic _) {
+  }
+  try {
+    self::C* c = new self::C::•();
+  }
+  on dynamic catch(final dynamic _) {
+  }
+}
diff --git a/pkg/front_end/testcases/regress/issue_35177.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_35177.dart.weak.modular.expect
new file mode 100644
index 0000000..d0eb552
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_35177.dart.weak.modular.expect
@@ -0,0 +1,8 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  () →* dynamic f;
+  f(){() →* dynamic}{dynamic}.call<core::int*>();
+}
diff --git a/pkg/front_end/testcases/regress/issue_35213.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_35213.dart.weak.modular.expect
new file mode 100644
index 0000000..e97491d
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_35213.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_35213.dart:5:9: Error: Expected ',' before this.
+// f(int a int b) { }
+//         ^^^
+//
+import self as self;
+import "dart:core" as core;
+
+static method f(core::int* a, core::int* b) → dynamic {}
+static method main() → dynamic {
+  self::f(2, 3);
+}
diff --git a/pkg/front_end/testcases/regress/issue_35220.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_35220.dart.weak.modular.expect
new file mode 100644
index 0000000..cab6aea
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_35220.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_35220.dart:6:25: Error: A value of type 'bool' can't be assigned to a variable of type 'A'.
+//  - 'A' is from 'pkg/front_end/testcases/regress/issue_35220.dart'.
+//   A bad() { return true != 2; }
+//                         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  method bad() → self::A* {
+    return invalid-expression "pkg/front_end/testcases/regress/issue_35220.dart:6:25: Error: A value of type 'bool' can't be assigned to a variable of type 'A'.
+ - 'A' is from 'pkg/front_end/testcases/regress/issue_35220.dart'.
+  A bad() { return true != 2; }
+                        ^" in !(true =={core::Object::==}{(core::Object*) →* core::bool*} 2) as{TypeError} self::A*;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_35258.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_35258.dart.weak.modular.expect
new file mode 100644
index 0000000..33c1bb2
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_35258.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_35258.dart:13:3: Error: 'C' is already declared in this scope.
+//   C(this.d) {}
+//   ^
+// pkg/front_end/testcases/regress/issue_35258.dart:12:3: Context: Previous declaration of 'C'.
+//   C() {}
+//   ^
+//
+// pkg/front_end/testcases/regress/issue_35258.dart:6:7: Error: Can't use 'C' because it is declared more than once.
+//   new C(42);
+//       ^
+//
+// pkg/front_end/testcases/regress/issue_35258.dart:10:9: Error: Final field 'd' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final d;
+//         ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  final field dynamic d = null;
+  constructor •() → self::C*
+    : super core::Object::•() {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/regress/issue_35258.dart:6:7: Error: Can't use 'C' because it is declared more than once.
+  new C(42);
+      ^";
+}
diff --git a/pkg/front_end/testcases/regress/issue_35259.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_35259.dart.weak.modular.expect
new file mode 100644
index 0000000..6a366d0
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_35259.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_35259.dart:7:11: Error: 'Supertype' is already declared in this scope.
+//   factory Supertype() = Unresolved;
+//           ^^^^^^^^^
+// pkg/front_end/testcases/regress/issue_35259.dart:6:11: Context: Previous declaration of 'Supertype'.
+//   factory Supertype() = Unresolved;
+//           ^^^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_35259.dart:6:25: Error: Couldn't find constructor 'Unresolved'.
+//   factory Supertype() = Unresolved;
+//                         ^
+//
+// pkg/front_end/testcases/regress/issue_35259.dart:7:25: Error: Couldn't find constructor 'Unresolved'.
+//   factory Supertype() = Unresolved;
+//                         ^
+//
+// pkg/front_end/testcases/regress/issue_35259.dart:7:25: Error: Redirection constructor target not found: 'Unresolved'
+//   factory Supertype() = Unresolved;
+//                         ^
+//
+// pkg/front_end/testcases/regress/issue_35259.dart:6:25: Error: Redirection constructor target not found: 'Unresolved'
+//   factory Supertype() = Unresolved;
+//                         ^
+//
+// pkg/front_end/testcases/regress/issue_35259.dart:11:13: Error: Can't use 'Supertype' because it is declared more than once.
+//   print(new Supertype());
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Supertype extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  static factory •() → self::Supertype*
+    return invalid-expression "pkg/front_end/testcases/regress/issue_35259.dart:6:25: Error: Redirection constructor target not found: 'Unresolved'
+  factory Supertype() = Unresolved;
+                        ^";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::print(invalid-expression "pkg/front_end/testcases/regress/issue_35259.dart:11:13: Error: Can't use 'Supertype' because it is declared more than once.
+  print(new Supertype());
+            ^");
+}
+
+constants  {
+  #C1 = constructor-tearoff self::Supertype::•
+}
diff --git a/pkg/front_end/testcases/regress/issue_35260.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_35260.dart.weak.modular.expect
new file mode 100644
index 0000000..0b4828a
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_35260.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_35260.dart:7:11: Error: 'Supertype' is already declared in this scope.
+//   factory Supertype() = X;
+//           ^^^^^^^^^
+// pkg/front_end/testcases/regress/issue_35260.dart:6:11: Context: Previous declaration of 'Supertype'.
+//   factory Supertype() = X;
+//           ^^^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_35260.dart:15:13: Error: Can't use 'Supertype' because it is declared more than once.
+//   X x = new Supertype();
+//             ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Supertype extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  static factory •() → self::Supertype*
+    return new self::X::•();
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class X extends core::Object implements self::Supertype {
+  constructor •() → self::X*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  self::X* x = invalid-expression "pkg/front_end/testcases/regress/issue_35260.dart:15:13: Error: Can't use 'Supertype' because it is declared more than once.
+  X x = new Supertype();
+            ^";
+}
+
+constants  {
+  #C1 = constructor-tearoff self::Supertype::•
+}
diff --git a/pkg/front_end/testcases/regress/issue_35266.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_35266.dart.weak.modular.expect
new file mode 100644
index 0000000..9885c52
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_35266.dart.weak.modular.expect
@@ -0,0 +1,56 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_35266.dart:8:11: Error: 'B.foo' is already declared in this scope.
+//   factory B.foo() = B<T>;
+//           ^^^^^
+// pkg/front_end/testcases/regress/issue_35266.dart:7:11: Context: Previous declaration of 'B.foo'.
+//   factory B.foo() = B<T>;
+//           ^^^^^
+//
+// pkg/front_end/testcases/regress/issue_35266.dart:13:21: Error: Can't use 'B.foo' because it is declared more than once.
+//   factory C.bar() = B<K>.foo;
+//                     ^
+//
+import self as self;
+import "dart:core" as core;
+
+class B<T extends core::Object* = dynamic> extends self::C<self::B::T*> {
+  static final field dynamic _redirecting# = <dynamic>[#C1];
+  constructor •() → self::B<self::B::T*>*
+    : super self::C::•()
+    ;
+  static factory foo<T extends core::Object* = dynamic>() → self::B<self::B::foo::T*>*
+    return new self::B::•<self::B::foo::T*>();
+}
+class C<K extends core::Object* = dynamic> extends core::Object {
+  static final field dynamic _redirecting# = <dynamic>[#C2];
+  constructor •() → self::C<self::C::K*>*
+    : super core::Object::•()
+    ;
+  static factory bar<K extends core::Object* = dynamic>() → self::C<self::C::bar::K*>*
+    return invalid-expression "pkg/front_end/testcases/regress/issue_35266.dart:13:21: Error: Can't use 'B.foo' because it is declared more than once.
+  factory C.bar() = B<K>.foo;
+                    ^";
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  invalid-expression "pkg/front_end/testcases/regress/issue_35266.dart:13:21: Error: Can't use 'B.foo' because it is declared more than once.
+  factory C.bar() = B<K>.foo;
+                    ^";
+}
+
+constants  {
+  #C1 = constructor-tearoff self::B::foo
+  #C2 = constructor-tearoff self::C::bar
+}
diff --git a/pkg/front_end/testcases/regress/issue_35900.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_35900.dart.weak.modular.expect
new file mode 100644
index 0000000..c6fc9e6
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_35900.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_35900.dart:5:25: Error: Can't find '}' to match '${'.
+// main () { int x; print('${x' '); }
+//                         ^
+//
+// pkg/front_end/testcases/regress/issue_35900.dart:5:24: Error: String starting with ' must end with '.
+// main () { int x; print('${x' '); }
+//                        ^^^^^^^^^^^^...
+//
+// pkg/front_end/testcases/regress/issue_35900.dart:6:1: Error: Expected a declaration, but got ''.
+//
+// pkg/front_end/testcases/regress/issue_35900.dart:5:28: Error: Expected '}' before this.
+// main () { int x; print('${x' '); }
+//                            ^^^
+//
+// pkg/front_end/testcases/regress/issue_35900.dart:5:31: Error: Expected a String, but got ')'.
+// main () { int x; print('${x' '); }
+//                               ^
+//
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::int* x;
+  core::print("${x}");
+}
diff --git a/pkg/front_end/testcases/regress/issue_36400.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_36400.dart.weak.modular.expect
new file mode 100644
index 0000000..3b5a369
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_36400.dart.weak.modular.expect
@@ -0,0 +1,27 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_36400.dart:6:3: Error: Factory constructors cannot have a return type.
+// Try removing the type appearing before 'factory'.
+//   Test factory Test() {
+//   ^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+class Test extends core::Object {
+  static factory •() → self::Test* {
+    return null;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
diff --git a/pkg/front_end/testcases/regress/issue_36647.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_36647.dart.weak.modular.expect
new file mode 100644
index 0000000..85c932b
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_36647.dart.weak.modular.expect
@@ -0,0 +1,85 @@
+library;
+import self as self;
+
+import "org-dartlang-testcase:///issue_36647_lib1.dart";
+
+
+library;
+import self as self2;
+import "issue_36647_lib2.dart" as iss;
+additionalExports = (iss::xxx,
+  iss::XXX,
+  iss::XXX,
+  iss::extends,
+  iss::extends)
+
+export "org-dartlang-testcase:///issue_36647_lib2.dart";
+
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_36647_lib2.dart:5:7: Error: A class declaration must have a body, even if it is empty.
+// Try adding an empty body.
+// class xxx xx XXX extends XXX {
+//       ^^^
+//
+// pkg/front_end/testcases/regress/issue_36647_lib2.dart:5:14: Error: Expected ';' after this.
+// class xxx xx XXX extends XXX {
+//              ^^^
+//
+// pkg/front_end/testcases/regress/issue_36647_lib2.dart:5:18: Error: Variables must be declared using the keywords 'const', 'final', 'var' or a type name.
+// Try adding the name of the type of the variable or the keyword 'var'.
+// class xxx xx XXX extends XXX {
+//                  ^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_36647_lib2.dart:5:18: Error: 'extends' can't be used as an identifier because it's a keyword.
+// Try renaming this to be an identifier that isn't a keyword.
+// class xxx xx XXX extends XXX {
+//                  ^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_36647_lib2.dart:5:18: Error: Expected ';' after this.
+// class xxx xx XXX extends XXX {
+//                  ^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_36647_lib2.dart:5:26: Error: A function declaration needs an explicit list of parameters.
+// Try adding a parameter list to the function declaration.
+// class xxx xx XXX extends XXX {
+//                          ^^^
+//
+// pkg/front_end/testcases/regress/issue_36647_lib2.dart:5:26: Error: 'XXX' is already declared in this scope.
+// class xxx xx XXX extends XXX {
+//                          ^^^
+// pkg/front_end/testcases/regress/issue_36647_lib2.dart:5:14: Context: Previous declaration of 'XXX'.
+// class xxx xx XXX extends XXX {
+//              ^^^
+//
+// pkg/front_end/testcases/regress/issue_36647_lib2.dart:5:11: Error: Type 'xx' not found.
+// class xxx xx XXX extends XXX {
+//           ^^
+//
+// pkg/front_end/testcases/regress/issue_36647_lib2.dart:5:11: Error: 'xx' isn't a type.
+// class xxx xx XXX extends XXX {
+//           ^^
+//
+import self as iss;
+import "dart:core" as core;
+
+class xxx extends core::Object {
+  synthetic constructor •() → iss::xxx*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field invalid-type XXX;
+static field dynamic extends;
diff --git a/pkg/front_end/testcases/regress/issue_36647_2.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_36647_2.dart.weak.modular.expect
new file mode 100644
index 0000000..79c30c6
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_36647_2.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library;
+import self as self;
+import "issue_36647_2_lib1.dart" as iss;
+additionalExports = (iss::foo,
+  iss::foo,
+  iss::bar,
+  iss::baz)
+
+export "org-dartlang-testcase:///issue_36647_2_lib1.dart";
+
+
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_36647_2_lib1.dart:6:5: Error: 'foo' is already declared in this scope.
+// int foo = 43;
+//     ^^^
+// pkg/front_end/testcases/regress/issue_36647_2_lib1.dart:5:5: Context: Previous declaration of 'foo'.
+// int foo = 42;
+//     ^^^
+//
+// pkg/front_end/testcases/regress/issue_36647_2_lib1.dart:8:14: Error: 'bar' is already declared in this scope.
+// typedef bool bar();
+//              ^^^
+// pkg/front_end/testcases/regress/issue_36647_2_lib1.dart:7:14: Context: Previous declaration of 'bar'.
+// typedef bool bar();
+//              ^^^
+//
+// pkg/front_end/testcases/regress/issue_36647_2_lib1.dart:13:5: Error: 'baz' is already declared in this scope.
+// int baz() {
+//     ^^^
+// pkg/front_end/testcases/regress/issue_36647_2_lib1.dart:9:5: Context: Previous declaration of 'baz'.
+// int baz() {
+//     ^^^
+//
+import self as iss;
+import "dart:core" as core;
+
+typedef bar = () →* core::bool*;
+static field core::int* foo;
+static method baz() → core::int* {
+  return 42;
+}
diff --git a/pkg/front_end/testcases/regress/issue_36669.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_36669.dart.weak.modular.expect
new file mode 100644
index 0000000..0c77dc9
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_36669.dart.weak.modular.expect
@@ -0,0 +1,51 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_36669.dart:11:7: Error: The superclass, 'NoUnnamedConstuctor with MixMeIn', has no unnamed constructor that takes no arguments.
+// class Foo extends NoUnnamedConstuctor with MixMeIn {}
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class NoUnnamedConstuctor extends core::Object {
+  constructor _() → self::NoUnnamedConstuctor*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class MixMeIn extends core::Object {
+  synthetic constructor •() → self::MixMeIn*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class _Foo&NoUnnamedConstuctor&MixMeIn = self::NoUnnamedConstuctor with self::MixMeIn /*isAnonymousMixin*/  {
+  synthetic constructor _() → self::_Foo&NoUnnamedConstuctor&MixMeIn*
+    : super self::NoUnnamedConstuctor::_()
+    ;
+}
+class Foo extends self::_Foo&NoUnnamedConstuctor&MixMeIn {
+  synthetic constructor •() → self::Foo*
+    : invalid-initializer
+    ;
+}
diff --git a/pkg/front_end/testcases/regress/issue_36793.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_36793.dart.weak.modular.expect
new file mode 100644
index 0000000..ac733f1
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_36793.dart.weak.modular.expect
@@ -0,0 +1,24 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_36793.dart:10:5: Error: 'x' is already declared in this scope.
+// int x = 2;
+//     ^
+// pkg/front_end/testcases/regress/issue_36793.dart:8:5: Context: Previous declaration of 'x'.
+// int x = 1;
+//     ^
+//
+import self as self;
+import "dart:core" as core;
+
+static const field core::int* y = #C1;
+@#C1
+static field core::int* x;
+static method main() → dynamic {
+  core::print(#C1);
+}
+
+constants  {
+  #C1 = 42
+}
diff --git a/pkg/front_end/testcases/regress/issue_37285.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_37285.dart.weak.modular.expect
new file mode 100644
index 0000000..84ceeef
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_37285.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_37285.dart:6:17: Error: Expected an identifier, but got ']'.
+// Try inserting an identifier before ']'.
+//   C() : super()[];
+//                 ^
+//
+// pkg/front_end/testcases/regress/issue_37285.dart:6:9: Error: Can't use 'super' as an expression.
+// To delegate a constructor to a super constructor, put the super call as an initializer.
+//   C() : super()[];
+//         ^
+//
+// pkg/front_end/testcases/regress/issue_37285.dart:6:16: Error: Not a valid initializer.
+// To initialize a field, use the syntax 'name = value'.
+//   C() : super()[];
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  constructor •() → self::C*
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/regress/issue_37285.dart:6:16: Error: Not a valid initializer.
+To initialize a field, use the syntax 'name = value'.
+  C() : super()[];
+               ^"
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  new self::C::•();
+}
diff --git a/pkg/front_end/testcases/regress/issue_37681.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_37681.dart.weak.modular.expect
new file mode 100644
index 0000000..c92257e
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_37681.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_37681.dart:6:7: Error: Functions marked 'async' must have a return type assignable to 'Future'.
+//   int f_async() async { return 42; }
+//       ^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_37681.dart:9:7: Error: Functions marked 'async*' must have a return type assignable to 'Stream'.
+//   int f_async_star() async* { yield 42; }
+//       ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/regress/issue_37681.dart:14:7: Error: Functions marked 'sync*' must have a return type assignable to 'Iterable'.
+//   int f_sync_star() sync* { yield 42; }
+//       ^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:async" as asy;
+
+static method main() → dynamic async {
+  function f_async() → core::int* async {
+    return 42;
+  }
+  core::print(await f_async(){() →* core::int*});
+  function f_async_star() → core::int* async* {
+    yield 42;
+  }
+  await for (dynamic x in (f_async_star(){() →* core::int*} as dynamic) as{TypeError,ForDynamic} asy::Stream<dynamic>*) {
+    core::print(x);
+  }
+  function f_sync_star() → core::int* sync* {
+    yield 42;
+  }
+  for (dynamic x in (f_sync_star(){() →* core::int*} as dynamic) as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+    core::print(x);
+  }
+}
diff --git a/pkg/front_end/testcases/regress/issue_39035.crash_dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_39035.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..6b4145e
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_39035.crash_dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_39035.crash_dart:5:4: Error: Can't find '}' to match '${'.
+// M("${)=
+//    ^
+//
+// pkg/front_end/testcases/regress/issue_39035.crash_dart:5:6: Error: String starting with " must end with ".
+// M("${)=
+//      ^^
+//
+// pkg/front_end/testcases/regress/issue_39035.crash_dart:5:3: Error: Expected an identifier, but got '"'.
+// Try inserting an identifier before '"'.
+// M("${)=
+//   ^
+//
+// pkg/front_end/testcases/regress/issue_39035.crash_dart:5:4: Error: Expected ')' before this.
+// M("${)=
+//    ^^
+//
+// pkg/front_end/testcases/regress/issue_39035.crash_dart:5:7: Error: Expected a function body or '=>'.
+// Try adding {}.
+// M("${)=
+//       ^
+//
+// pkg/front_end/testcases/regress/issue_39035.crash_dart:5:7: Error: Expected ';' after this.
+// M("${)=
+//       ^
+//
+// pkg/front_end/testcases/regress/issue_39035.crash_dart:5:8: Error: Unexpected token ''.
+// M("${)=
+//        ^...
+//
+import self as self;
+
+static method M() → dynamic
+  return "";
diff --git a/pkg/front_end/testcases/regress/issue_39040.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_39040.dart.weak.modular.expect
new file mode 100644
index 0000000..ade6db2
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_39040.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → void {
+  core::List<core::String*>* whereWasI = <core::String*>[];
+  core::int* outer = 1;
+  core::int* inner = 0;
+  #L1:
+  switch(outer) {
+    #L2:
+    case #C1:
+      {
+        whereWasI.{core::List::add}("outer 0"){(core::String*) →* void};
+        break #L1;
+      }
+    #L3:
+    case #C2:
+      {
+        (() → Null {
+          switch(inner) {
+            #L4:
+            case #C1:
+              {
+                whereWasI.{core::List::add}("inner 0"){(core::String*) →* void};
+                continue #L5;
+              }
+            #L5:
+            case #C2:
+              {
+                whereWasI.{core::List::add}("inner 1"){(core::String*) →* void};
+              }
+          }
+        })(){() →* Null};
+      }
+  }
+  if(!(whereWasI.{core::List::length}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} 2) || !(whereWasI.{core::List::[]}(0){(core::int*) →* core::String*} =={core::String::==}{(core::Object*) →* core::bool*} "inner 0") || !(whereWasI.{core::List::[]}(1){(core::int*) →* core::String*} =={core::String::==}{(core::Object*) →* core::bool*} "inner 1")) {
+    throw "Unexpected path.";
+  }
+  core::print(whereWasI);
+}
+
+constants  {
+  #C1 = 0
+  #C2 = 1
+}
diff --git a/pkg/front_end/testcases/regress/issue_39091_1.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_39091_1.dart.weak.modular.expect
new file mode 100644
index 0000000..c414477
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_39091_1.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_39091_1.dart:5:1: Error: Variables must be declared using the keywords 'const', 'final', 'var' or a type name.
+// Try adding the name of the type of the variable or the keyword 'var'.
+// hello
+// ^^^^^
+//
+// pkg/front_end/testcases/regress/issue_39091_1.dart:5:1: Error: Expected ';' after this.
+// hello
+// ^^^^^
+//
+import self as self;
+
+static field dynamic hello;
diff --git a/pkg/front_end/testcases/regress/issue_39091_2.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_39091_2.dart.weak.modular.expect
new file mode 100644
index 0000000..0ebcc72
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_39091_2.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_39091_2.dart:1:1: Error: The non-ASCII space character U+FEFF can only be used in strings and comments.
+// ﻿// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// ^
+//
+// pkg/front_end/testcases/regress/issue_39091_2.dart:13:1: Error: Expected a declaration, but got '"﻿"'.
+// "﻿";
+// ^^^
+//
+// pkg/front_end/testcases/regress/issue_39091_2.dart:13:4: Error: Unexpected token ';'.
+// "﻿";
+//    ^
+//
+// pkg/front_end/testcases/regress/issue_39091_2.dart:11:11: Error: Undefined name 'hello'.
+// "﻿";/*æ*/ hello; /*æ*/
+//           ^^^^^
+//
+import self as self;
+
+static method main() → dynamic {
+  "\u65279";
+  "\u65279";
+  "\u65279";
+  "\u65279";
+  "A";
+  "\u65279";
+  "\u65279";
+  invalid-expression "pkg/front_end/testcases/regress/issue_39091_2.dart:11:11: Error: Undefined name 'hello'.
+\"\u65279\";/*\u0230*/ hello; /*\u0230*/
+          ^^^^^";
+}
diff --git a/pkg/front_end/testcases/regress/issue_39682.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_39682.dart.weak.modular.expect
new file mode 100644
index 0000000..9866587
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_39682.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library;
+import self as self;
+import "dart:async" as asy;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///issue_39682_lib.dart" deferred as foo;
+
+static method main() → dynamic {
+  () →* asy::Future<dynamic>* f = #C1;
+  f(){() →* asy::Future<dynamic>*};
+  core::print(self::__loadLibrary_foo());
+}
+static method __loadLibrary_foo() → core::String* {
+  return "I'll call my methods what I want!";
+}
+static method _#loadLibrary_foo() → asy::Future<dynamic>*
+  return LoadLibrary(foo);
+
+library;
+import self as self2;
+import "dart:core" as core;
+
+static method foo() → dynamic {
+  core::print("foo!");
+}
+
+constants  {
+  #C1 = static-tearoff self::_#loadLibrary_foo
+}
diff --git a/pkg/front_end/testcases/regress/issue_41265.crash_dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_41265.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..03c63ac
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_41265.crash_dart.weak.modular.expect
@@ -0,0 +1,73 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/regress/issue_41265.crash_dart:9:53: Error: Unexpected token '>'.
+// class DND1 extends Object with M<dynamic> Function()> {
+//                                                     ^
+//
+// pkg/front_end/testcases/regress/issue_41265.crash_dart:9:7: Error: The type '() -> M<dynamic>' can't be mixed in.
+// class DND1 extends Object with M<dynamic> Function()> {
+//       ^
+//
+// pkg/front_end/testcases/regress/issue_41265.crash_dart:12:7: Error: The type '() -> M<dynamic>' can't be mixed in.
+// class DND2 extends Object with M<dynamic> Function() {
+//       ^
+//
+// pkg/front_end/testcases/regress/issue_41265.crash_dart:9:7: Error: Can't use a function type as supertype.
+// class DND1 extends Object with M<dynamic> Function()> {
+//       ^
+//
+// pkg/front_end/testcases/regress/issue_41265.crash_dart:12:7: Error: Can't use a function type as supertype.
+// class DND2 extends Object with M<dynamic> Function() {
+//       ^
+//
+// pkg/front_end/testcases/regress/issue_41265.crash_dart:15:7: Error: Can't use a function type as supertype.
+// class DND3 extends M<dynamic> Function() {
+//       ^
+//
+// pkg/front_end/testcases/regress/issue_41265.crash_dart:18:7: Error: Can't use a function type as supertype.
+// class DND4 implements M<dynamic> Function() {
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::T%>
+    : super core::Object::•()
+    ;
+}
+abstract class M<T extends core::Object? = dynamic> extends core::Object /*isMixinDeclaration*/  {
+}
+abstract class _DND1&Object extends core::Object /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_DND1&Object
+    : super core::Object::•()
+    ;
+}
+class DND1 extends self::_DND1&Object {
+  synthetic constructor •() → self::DND1
+    : super self::_DND1&Object::•()
+    ;
+}
+abstract class _DND2&Object extends core::Object /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_DND2&Object
+    : super core::Object::•()
+    ;
+}
+class DND2 extends self::_DND2&Object {
+  synthetic constructor •() → self::DND2
+    : super self::_DND2&Object::•()
+    ;
+}
+class DND3 extends core::Object {
+  synthetic constructor •() → self::DND3
+    : super core::Object::•()
+    ;
+}
+class DND4 extends core::Object {
+  synthetic constructor •() → self::DND4
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/regress/issue_42423.dart.weak.modular.expect b/pkg/front_end/testcases/regress/issue_42423.dart.weak.modular.expect
new file mode 100644
index 0000000..ed0856a
--- /dev/null
+++ b/pkg/front_end/testcases/regress/issue_42423.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+import "package:expect/expect.dart" as exp;
+
+import "package:expect/expect.dart";
+
+static method test1(dynamic stringList) → dynamic {
+  core::Set<core::int*>* intSet = block {
+    final core::Set<core::int*>* #t1 = col::LinkedHashSet::•<core::int*>();
+    final core::Iterable<dynamic>* #t2 = stringList as{TypeError,ForDynamic} core::Iterable<dynamic>*;
+    if(!(#t2 == null))
+      for (final dynamic #t3 in #t2) {
+        final core::int* #t4 = #t3 as{TypeError} core::int*;
+        #t1.{core::Set::add}{Invariant}(#t4){(core::int*) →* core::bool*};
+      }
+  } =>#t1;
+}
+static method test2(dynamic stringList) → dynamic {
+  core::List<core::int*>* intList = block {
+    final core::List<core::int*>* #t5 = <core::int*>[];
+    final core::Iterable<dynamic>* #t6 = stringList as{TypeError,ForDynamic} core::Iterable<dynamic>*;
+    if(!(#t6 == null))
+      for (final dynamic #t7 in #t6) {
+        final core::int* #t8 = #t7 as{TypeError} core::int*;
+        #t5.{core::List::add}{Invariant}(#t8){(core::int*) →* void};
+      }
+  } =>#t5;
+}
+static method test3(dynamic stringMap) → dynamic {
+  core::Map<core::int*, core::int*>* intMap = block {
+    final core::Map<core::int*, core::int*>* #t9 = <core::int*, core::int*>{};
+    final core::Map<dynamic, dynamic>* #t10 = stringMap as{TypeError,ForDynamic} core::Map<dynamic, dynamic>*;
+    if(!(#t10 == null))
+      for (final core::MapEntry<dynamic, dynamic>* #t11 in #t10.{core::Map::entries}{core::Iterable<core::MapEntry<core::int*, core::int*>>}) {
+        final core::int* #t12 = #t11.{core::MapEntry::key}{dynamic} as{TypeError} core::int*;
+        final core::int* #t13 = #t11.{core::MapEntry::value}{dynamic} as{TypeError} core::int*;
+        #t9.{core::Map::[]=}{Invariant}(#t12, #t13){(core::int*, core::int*) →* void};
+      }
+  } =>#t9;
+}
+static method main() → dynamic {
+  dynamic stringList = <core::String*>["string"];
+  exp::Expect::throwsTypeError(() → Null {
+    self::test1(stringList);
+  });
+  exp::Expect::throwsTypeError(() → Null {
+    self::test2(stringList);
+  });
+  dynamic stringMap = <core::String*, core::String*>{"a": "b"};
+  exp::Expect::throwsTypeError(() → Null {
+    self::test3(stringMap);
+  });
+}
diff --git a/pkg/front_end/testcases/regress/utf_16_le_content.crash_dart.weak.modular.expect b/pkg/front_end/testcases/regress/utf_16_le_content.crash_dart.weak.modular.expect
new file mode 100644
index 0000000..bfc33bf
--- /dev/null
+++ b/pkg/front_end/testcases/regress/utf_16_le_content.crash_dart.weak.modular.expect
Binary files differ
diff --git a/pkg/front_end/testcases/runtime_checks/call_kinds.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/call_kinds.dart.weak.modular.expect
new file mode 100644
index 0000000..d6a32ed
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/call_kinds.dart.weak.modular.expect
@@ -0,0 +1,42 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F = () →* void;
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f() → void {}
+  get g() → () →* void
+    return null;
+  get h() → dynamic
+    return null;
+  method test() → void {
+    this.{self::C::f}(){() →* void};
+    this.{self::C::f}(){() →* void};
+    this.{self::C::g}{() →* void}(){() →* void};
+    this.{self::C::g}{() →* void}(){() →* void};
+    this.{self::C::h}{dynamic}{dynamic}.call();
+    this.{self::C::h}{dynamic}{dynamic}.call();
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test(self::C* c, () →* void f, dynamic d) → void {
+  c.{self::C::f}(){() →* void};
+  f(){() →* void};
+  d{dynamic}.call();
+  d{dynamic}.f();
+  c.{self::C::g}{() →* void}(){() →* void};
+  c.{self::C::h}{dynamic}{dynamic}.call();
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks/call_kinds_get.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/call_kinds_get.dart.weak.modular.expect
new file mode 100644
index 0000000..96f9b35
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/call_kinds_get.dart.weak.modular.expect
@@ -0,0 +1,34 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field dynamic y = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  get x() → dynamic
+    return null;
+  method test() → void {
+    dynamic v1 = this.{self::C::x}{dynamic};
+    dynamic v2 = this.{self::C::x}{dynamic};
+    dynamic v3 = this.{self::C::y}{dynamic};
+    dynamic v4 = this.{self::C::y}{dynamic};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test(self::C* c, dynamic d) → void {
+  dynamic v1 = c.{self::C::x}{dynamic};
+  dynamic v2 = c.{self::C::y}{dynamic};
+  dynamic v3 = d{dynamic}.x;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks/call_kinds_set.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/call_kinds_set.dart.weak.modular.expect
new file mode 100644
index 0000000..a78157b
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/call_kinds_set.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field dynamic y = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  set x(dynamic value) → void {}
+  method test() → void {
+    this.{self::C::x} = null;
+    this.{self::C::x} = null;
+    this.{self::C::y} = null;
+    this.{self::C::y} = null;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test(self::C* c, dynamic d) → void {
+  c.{self::C::x} = null;
+  c.{self::C::y} = null;
+  d{dynamic}.x = null;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks/call_method_implicit_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/call_method_implicit_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..bffdb53
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/call_method_implicit_tear_off.dart.weak.modular.expect
@@ -0,0 +1,23 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method call() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  () →* void x = let final self::C* #t1 = new self::C::•() in #t1 == null ?{() →* void} null : #t1.{self::C::call}{() →* void};
+}
diff --git a/pkg/front_end/testcases/runtime_checks/call_method_implicit_tear_off_future_or.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/call_method_implicit_tear_off_future_or.dart.weak.modular.expect
new file mode 100644
index 0000000..edf5d5c
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/call_method_implicit_tear_off_future_or.dart.weak.modular.expect
@@ -0,0 +1,25 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+import "dart:async";
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method call() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  FutureOr<() →* void>* x = let final self::C* #t1 = new self::C::•() in #t1 == null ?{() →* void} null : #t1.{self::C::call}{() →* void};
+}
diff --git a/pkg/front_end/testcases/runtime_checks/contravariant_field.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/contravariant_field.dart.weak.modular.expect
new file mode 100644
index 0000000..2142878
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/contravariant_field.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+class C<T extends core::Object* = dynamic> extends core::Object {
+  field (self::C::T*) →* void y = null;
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method f() → void {
+    (self::C::T*) →* void x = this.{self::C::y}{(self::C::T*) →* void};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g(self::C<core::num*>* c) → void {
+  (core::num*) →* void x = c.{self::C::y}{(core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void;
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks/contravariant_generic_method_type_parameter.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/contravariant_generic_method_type_parameter.dart.weak.modular.expect
new file mode 100644
index 0000000..3e9cb61
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/contravariant_generic_method_type_parameter.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method f<U extends (self::C::T*) →* void>(self::C::f::U* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g(self::C<core::num*>* c) → void {
+  c.{self::C::f}<(core::Object*) →* void>((core::Object* o) → Null {}){((core::Object*) →* void) →* void};
+}
+static method test() → void {
+  self::g(new self::C::•<core::int*>());
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks/contravariant_generic_return.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/contravariant_generic_return.dart.weak.modular.expect
new file mode 100644
index 0000000..a1cb113
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/contravariant_generic_return.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method f1() → (self::C::T*) →* void {}
+  method f2() → core::List<(self::C::T*) →* void>* {
+    return <(self::C::T*) →* void>[this.{self::C::f1}(){() →* (self::C::T*) →* void}];
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g1(self::C<core::num*>* c) → void {
+  (core::num*) →* void x = c.{self::C::f1}(){() →* (core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void;
+  core::print("hello");
+  x(1.5){(core::num*) →* void};
+}
+static method g2(self::C<core::num*>* c) → void {
+  (core::int*) →* void x = c.{self::C::f1}(){() →* (core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void;
+  x(1){(core::int*) →* void};
+}
+static method g3(self::C<core::num*>* c) → void {
+  core::List<(core::num*) →* void>* x = c.{self::C::f2}(){() →* core::List<(core::num*) →* void>*} as{TypeError,CovarianceCheck} core::List<(core::num*) →* void>*;
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks/contravariant_generic_return_null_aware.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/contravariant_generic_return_null_aware.dart.weak.modular.expect
new file mode 100644
index 0000000..a8aa298
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/contravariant_generic_return_null_aware.dart.weak.modular.expect
@@ -0,0 +1,37 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method f1() → (self::C::T*) →* void {}
+  method f2() → core::List<(self::C::T*) →* void>* {
+    return <(self::C::T*) →* void>[this.{self::C::f1}(){() →* (self::C::T*) →* void}];
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g1(self::C<core::num*>* c) → void {
+  (core::num*) →* void x = let final self::C<core::num*>* #t1 = c in #t1 == null ?{(core::num*) →* void} null : #t1.{self::C::f1}(){() →* (core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void;
+  core::print("hello");
+  x(1.5){(core::num*) →* void};
+}
+static method g2(self::C<core::num*>* c) → void {
+  (core::int*) →* void x = let final self::C<core::num*>* #t2 = c in #t2 == null ?{(core::num*) →* void} null : #t2.{self::C::f1}(){() →* (core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void;
+  x(1){(core::int*) →* void};
+}
+static method g3(self::C<core::num*>* c) → void {
+  core::List<(core::num*) →* void>* x = let final self::C<core::num*>* #t3 = c in #t3 == null ?{core::List<(core::num*) →* void>*} null : #t3.{self::C::f2}(){() →* core::List<(core::num*) →* void>*} as{TypeError,CovarianceCheck} core::List<(core::num*) →* void>*;
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks/contravariant_generic_return_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/contravariant_generic_return_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..3f796f1
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/contravariant_generic_return_tear_off.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+typedef G<contravariant T extends core::Object* = dynamic> = () →* (T*) →* void;
+class C<T extends core::Object* = dynamic> extends core::Object {
+  field (self::C::T*) →* void _x;
+  constructor •((self::C::T*) →* void _x) → self::C<self::C::T*>*
+    : self::C::_x = _x, super core::Object::•()
+    ;
+  method f() → (self::C::T*) →* void
+    return this.{self::C::_x}{(self::C::T*) →* void};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g(self::C<core::num*>* c) → () →* (core::num*) →* void {
+  return c.{self::C::f}{() →* (core::num*) →* void} as{TypeError,CovarianceCheck} () →* (core::num*) →* void;
+}
+static method h(core::int* i) → void {
+  core::print("${i}");
+}
+static method test() → void {
+  () →* (core::num*) →* void x = self::g(new self::C::•<core::int*>(#C1));
+}
+static method main() → void {}
+
+constants  {
+  #C1 = static-tearoff self::h
+}
diff --git a/pkg/front_end/testcases/runtime_checks/contravariant_getter.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/contravariant_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..d641b1f
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/contravariant_getter.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+class C<T extends core::Object* = dynamic> extends core::Object {
+  field (self::C::T*) →* void y = null;
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method f(covariant-by-class self::C::T* value) → void {
+    let final self::C::T* #t1 = value in this.{self::C::y}{(self::C::T*) →* void}(#t1){(self::C::T*) →* void};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g(self::C<core::num*>* c) → void {
+  let final self::C<core::num*>* #t2 = c in let final core::double* #t3 = 1.5 in (#t2.{self::C::y}{(core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void)(#t3){(core::num*) →* void};
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks/contravariant_getter_return.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/contravariant_getter_return.dart.weak.modular.expect
new file mode 100644
index 0000000..60445df
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/contravariant_getter_return.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  get f1() → (self::C::T*) →* void
+    return null;
+  get f2() → core::List<(self::C::T*) →* void>* {
+    return <(self::C::T*) →* void>[this.{self::C::f1}{(self::C::T*) →* void}];
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g1(self::C<core::num*>* c) → void {
+  (core::num*) →* void x = c.{self::C::f1}{(core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void;
+  core::print("hello");
+  x(1.5){(core::num*) →* void};
+}
+static method g2(self::C<core::num*>* c) → void {
+  (core::int*) →* void x = c.{self::C::f1}{(core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void;
+  x(1){(core::int*) →* void};
+}
+static method g3(self::C<core::num*>* c) → void {
+  core::List<(core::num*) →* void>* x = c.{self::C::f2}{core::List<(core::num*) →* void>*} as{TypeError,CovarianceCheck} core::List<(core::num*) →* void>*;
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks/contravariant_getter_return_null_aware.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/contravariant_getter_return_null_aware.dart.weak.modular.expect
new file mode 100644
index 0000000..98e1172
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/contravariant_getter_return_null_aware.dart.weak.modular.expect
@@ -0,0 +1,38 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  get f1() → (self::C::T*) →* void
+    return null;
+  get f2() → core::List<(self::C::T*) →* void>* {
+    return <(self::C::T*) →* void>[this.{self::C::f1}{(self::C::T*) →* void}];
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g1(self::C<core::num*>* c) → void {
+  (core::num*) →* void x = let final self::C<core::num*>* #t1 = c in #t1 == null ?{(core::num*) →* void} null : #t1.{self::C::f1}{(core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void;
+  core::print("hello");
+  x(1.5){(core::num*) →* void};
+}
+static method g2(self::C<core::num*>* c) → void {
+  (core::int*) →* void x = let final self::C<core::num*>* #t2 = c in #t2 == null ?{(core::num*) →* void} null : #t2.{self::C::f1}{(core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void;
+  x(1){(core::int*) →* void};
+}
+static method g3(self::C<core::num*>* c) → void {
+  core::List<(core::num*) →* void>* x = let final self::C<core::num*>* #t3 = c in #t3 == null ?{core::List<(core::num*) →* void>*} null : #t3.{self::C::f2}{core::List<(core::num*) →* void>*} as{TypeError,CovarianceCheck} core::List<(core::num*) →* void>*;
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks/covariant_generic_method_type_parameter.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/covariant_generic_method_type_parameter.dart.weak.modular.expect
new file mode 100644
index 0000000..23d142c
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/covariant_generic_method_type_parameter.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/runtime_checks/covariant_generic_method_type_parameter.dart:11:15: Error: The argument type 'double' can't be assigned to the parameter type 'U'.
+//     this.f<U>(1.5);
+//               ^
+//
+// pkg/front_end/testcases/runtime_checks/covariant_generic_method_type_parameter.dart:20:16: Error: Type argument 'num' doesn't conform to the bound 'int' of the type variable 'U' on 'C<int>.g1'.
+//  - 'C' is from 'pkg/front_end/testcases/runtime_checks/covariant_generic_method_type_parameter.dart'.
+// Try changing type arguments so that they conform to the bounds.
+//   new C<int>().g1<num>();
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method f<covariant-by-class U extends self::C::T*>(self::C::f::U* x) → void {}
+  method g1<covariant-by-class U extends self::C::T*>() → void {
+    this.{self::C::f}<self::C::g1::U*>(invalid-expression "pkg/front_end/testcases/runtime_checks/covariant_generic_method_type_parameter.dart:11:15: Error: The argument type 'double' can't be assigned to the parameter type 'U'.
+    this.f<U>(1.5);
+              ^" in 1.5 as{TypeError} Never){(self::C::g1::U*) →* void};
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g2(self::C<core::Object*>* c) → void {
+  c.{self::C::f}<core::num*>(1.5){(core::num*) →* void};
+}
+static method test() → void {
+  new self::C::•<core::int*>().{self::C::g1}<core::num*>(){() →* void};
+  self::g2(new self::C::•<core::int*>());
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter.dart.weak.modular.expect
new file mode 100644
index 0000000..2794c16
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method f(covariant-by-class self::C::T* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g1(self::C<core::num*>* c) → void {
+  c.{self::C::f}(1.5){(core::num*) →* void};
+}
+static method g2(self::C<core::int*>* c) → void {
+  c.{self::C::f}(1){(core::int*) →* void};
+}
+static method g3(self::C<core::num*>* c) → void {
+  c.{self::C::f}(null){(core::num*) →* void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_complex.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_complex.dart.weak.modular.expect
new file mode 100644
index 0000000..41147c6
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_complex.dart.weak.modular.expect
@@ -0,0 +1,36 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method f1(covariant-by-class core::List<self::C::T*>* x) → void {}
+  method f2(covariant-by-class () →* self::C::T* callback) → void {}
+  method f3(covariant-by-class (self::C::T*) →* self::C::T* callback) → void {}
+  method f4((self::C::T*) →* void callback) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g1(self::C<core::num*>* c, core::List<core::num*>* l) → void {
+  c.{self::C::f1}(l){(core::List<core::num*>*) →* void};
+}
+static method g2(self::C<core::num*>* c, () →* core::num* callback) → void {
+  c.{self::C::f2}(callback){(() →* core::num*) →* void};
+}
+static method g3(self::C<core::num*>* c, (core::num*) →* core::num* callback) → void {
+  c.{self::C::f3}(callback){((core::num*) →* core::num*) →* void};
+}
+static method g4(self::C<core::num*>* c, (core::num*) →* void callback) → void {
+  c.{self::C::f4}(callback){((core::num*) →* void) →* void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_in_interface.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_in_interface.dart.weak.modular.expect
new file mode 100644
index 0000000..b492a06
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_in_interface.dart.weak.modular.expect
@@ -0,0 +1,68 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class I<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::T*>*
+    : super core::Object::•()
+    ;
+  abstract method f1(covariant-by-class self::I::T* x) → void;
+  abstract method f2(covariant-by-class self::I::T* x) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<U extends core::Object* = dynamic> extends core::Object implements self::I<core::int*> {
+  synthetic constructor •() → self::C<self::C::U*>*
+    : super core::Object::•()
+    ;
+  method f1(covariant-by-class core::int* x) → void {}
+  method f2(covariant-by-class core::int* x, [covariant-by-class self::C::U* y = #C1]) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D<U extends core::Object* = dynamic> extends self::C<self::D::U*> {
+  synthetic constructor •() → self::D<self::D::U*>*
+    : super self::C::•()
+    ;
+  method f1(covariant-by-class core::int* x) → void {}
+  method f2(covariant-by-class core::int* x, [covariant-by-class self::D::U* y = #C1]) → void {}
+}
+static method g1(self::C<core::num*>* c) → void {
+  c.{self::C::f1}(1){(core::int*) →* void};
+}
+static method g2(self::I<core::num*>* i) → void {
+  i.{self::I::f1}(1.5){(core::num*) →* void};
+}
+static method g3(self::C<core::num*>* c) → void {
+  c.{self::C::f2}(1, 1.5){(core::int*, [core::num*]) →* void};
+}
+static method g4(self::D<core::num*>* d) → void {
+  d.{self::D::f1}(1){(core::int*) →* void};
+}
+static method g5(self::D<core::num*>* d) → void {
+  d.{self::D::f2}(1, 1.5){(core::int*, [core::num*]) →* void};
+}
+static method test() → void {
+  self::g2(new self::C::•<core::num*>());
+}
+static method main() → void {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_in_interface_mixin.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_in_interface_mixin.dart.weak.modular.expect
new file mode 100644
index 0000000..c7a7694
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_in_interface_mixin.dart.weak.modular.expect
@@ -0,0 +1,69 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method f(core::int* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::T*>*
+    : super core::Object::•()
+    ;
+  abstract method f(covariant-by-class self::I::T* x) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M extends core::Object {
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  method f(core::int* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C = self::B with self::M implements self::I<core::int*> {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  forwarding-stub method f(covariant-by-class core::int* x) → void
+    return super.{self::M::f}(x);
+}
+static method g1(self::C* c) → void {
+  c.{self::C::f}(1){(core::int*) →* void};
+}
+static method g2(self::I<core::num*>* i) → void {
+  i.{self::I::f}(1.5){(core::num*) →* void};
+}
+static method test() → void {
+  self::g2(new self::C::•());
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_in_interface_super.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_in_interface_super.dart.weak.modular.expect
new file mode 100644
index 0000000..5e85a90
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_in_interface_super.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method f(core::int* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::T*>*
+    : super core::Object::•()
+    ;
+  abstract method f(covariant-by-class self::I::T* x) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B implements self::I<core::int*> {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  forwarding-stub method f(covariant-by-class core::int* x) → void
+    return super.{self::B::f}(x);
+}
+static method g1(self::C* c) → void {
+  c.{self::C::f}(1){(core::int*) →* void};
+}
+static method g2(self::I<core::num*>* i) → void {
+  i.{self::I::f}(1.5){(core::num*) →* void};
+}
+static method test() → void {
+  self::g2(new self::C::•());
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_in_interface_super_mixin.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_in_interface_super_mixin.dart.weak.modular.expect
new file mode 100644
index 0000000..e69ba31
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_in_interface_super_mixin.dart.weak.modular.expect
@@ -0,0 +1,68 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method f(core::int* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::T*>*
+    : super core::Object::•()
+    ;
+  abstract method f(covariant-by-class self::I::T* x) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M extends core::Object {
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C = self::B with self::M implements self::I<core::int*> {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  forwarding-stub method f(covariant-by-class core::int* x) → void
+    return super.{self::B::f}(x);
+}
+static method g1(self::C* c) → void {
+  c.{self::C::f}(1){(core::int*) →* void};
+}
+static method g2(self::I<core::num*>* i) → void {
+  i.{self::I::f}(1.5){(core::num*) →* void};
+}
+static method test() → void {
+  self::g2(new self::C::•());
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_tear_off.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_tear_off.dart.weak.modular.expect
new file mode 100644
index 0000000..a63dac3
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/covariant_generic_parameter_tear_off.dart.weak.modular.expect
@@ -0,0 +1,40 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+typedef G<contravariant T extends core::Object* = dynamic, U extends core::Object* = dynamic> = (T*) →* U*;
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method f1(covariant-by-class self::C::T* x) → void {}
+  method f2(covariant-by-class core::List<self::C::T*>* x) → self::C::T*
+    return x.{core::Iterable::first}{self::C::T*};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g1(self::C<core::num*>* c) → (core::num*) →* void {
+  return c.{self::C::f1}{(core::num*) →* void};
+}
+static method g2(self::C<core::int*>* c, core::Object* x) → void {
+  (core::Object*) →* void f = self::g1(c) as (core::Object*) →* void;
+  f(x){(core::Object*) →* void};
+}
+static method g3(self::C<core::num*>* c) → (core::List<core::num*>*) →* core::num* {
+  return c.{self::C::f2}{(core::List<core::num*>*) →* core::num*};
+}
+static method test() → void {
+  (core::num*) →* void x = self::g1(new self::C::•<core::int*>());
+  x(1.5){(core::num*) →* void};
+  self::g3(new self::C::•<core::int*>());
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks/covariant_keyword.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/covariant_keyword.dart.weak.modular.expect
new file mode 100644
index 0000000..bf44b39
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/covariant_keyword.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* dynamic;
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  method f(core::num* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method f(covariant-by-declaration core::int* x) → void {}
+}
+class E extends self::D {
+  synthetic constructor •() → self::E*
+    : super self::D::•()
+    ;
+  method f(covariant-by-declaration core::int* x) → void {}
+}
+static method g1(self::C* c) → void {
+  c.{self::C::f}(1.5){(core::num*) →* void};
+}
+static method g2(self::C* c) → (core::num*) →* dynamic {
+  return c.{self::C::f}{(core::num*) →* void};
+}
+static method test() → dynamic {
+  self::g1(new self::D::•());
+  (core::num*) →* dynamic x = self::g2(new self::D::•());
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks/covariant_keyword_field.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/covariant_keyword_field.dart.weak.modular.expect
new file mode 100644
index 0000000..210c2cb
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/covariant_keyword_field.dart.weak.modular.expect
@@ -0,0 +1,53 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field core::num* x = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends core::Object implements self::C {
+  covariant-by-declaration field core::int* x = null;
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E extends core::Object implements self::D {
+  covariant-by-declaration field core::int* x = null;
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks/covariant_keyword_field_inherited_by_setter.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/covariant_keyword_field_inherited_by_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..2e274f6
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/covariant_keyword_field_inherited_by_setter.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field core::num* x = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends core::Object implements self::C {
+  covariant-by-declaration field core::int* x = null;
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E extends core::Object implements self::D {
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  get x() → core::int*
+    return 0;
+  set x(covariant-by-declaration core::int* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks/covariant_keyword_setter.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/covariant_keyword_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..3f5f3e4
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/covariant_keyword_setter.dart.weak.modular.expect
@@ -0,0 +1,33 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  set x(core::num* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  set x(covariant-by-declaration core::int* value) → void {}
+}
+class E extends self::D {
+  synthetic constructor •() → self::E*
+    : super self::D::•()
+    ;
+  set x(covariant-by-declaration core::int* value) → void {}
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks/covariant_keyword_setter_inherited_by_field.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/covariant_keyword_setter_inherited_by_field.dart.weak.modular.expect
new file mode 100644
index 0000000..8c69a30
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/covariant_keyword_setter_inherited_by_field.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  set x(core::num* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  set x(covariant-by-declaration core::int* value) → void {}
+}
+class E extends core::Object implements self::D {
+  covariant-by-declaration field core::int* x = null;
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks/covariant_setter.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/covariant_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..dee3331
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/covariant_setter.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+class C<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::C::T* x = null;
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  set y(covariant-by-class self::C::T* value) → void {}
+  method f(covariant-by-class self::C::T* value) → void {
+    this.{self::C::x} = value;
+    this.{self::C::y} = value;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g(self::C<core::num*>* c) → void {
+  c.{self::C::x} = 1.5;
+  c.{self::C::y} = 1.5;
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks/dynamic_invocation.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/dynamic_invocation.dart.weak.modular.expect
new file mode 100644
index 0000000..3d1a3dc
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/dynamic_invocation.dart.weak.modular.expect
@@ -0,0 +1,39 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method f1(covariant-by-class self::C::T* x) → void {}
+  method f2(core::int* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C<core::num*> {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  method f1(covariant-by-declaration covariant-by-class core::int* x) → void {}
+}
+static method g1(dynamic d) → void {
+  d{dynamic}.f1(1.5);
+}
+static method g2(dynamic d) → void {
+  d{dynamic}.f2(1.5);
+}
+static method test() → void {
+  self::g1(new self::C::•<core::int*>());
+  self::g2(new self::C::•<dynamic>());
+  self::g1(new self::D::•());
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks/dynamic_invocation_generic.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/dynamic_invocation_generic.dart.weak.modular.expect
new file mode 100644
index 0000000..bbd989a
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/dynamic_invocation_generic.dart.weak.modular.expect
@@ -0,0 +1,31 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method f<covariant-by-class U extends self::C::T*>(self::C::f::U* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g1(dynamic d) → void {
+  d{dynamic}.f<core::num*>(1.5);
+}
+static method g2(dynamic d) → void {
+  d{dynamic}.f(1.5);
+}
+static method test() → void {
+  self::g1(new self::C::•<core::int*>());
+  self::g2(new self::C::•<core::int*>());
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks/dynamic_invocation_of_getter.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/dynamic_invocation_of_getter.dart.weak.modular.expect
new file mode 100644
index 0000000..204effc
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/dynamic_invocation_of_getter.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field dynamic f;
+  constructor •(dynamic f) → self::C*
+    : self::C::f = f, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method g(self::C* c) → void {
+  let final self::C* #t1 = c in let final core::double* #t2 = 1.5 in #t1.{self::C::f}{dynamic}{dynamic}.call(#t2);
+}
+static method h(core::int* i) → void {}
+static method test() → void {
+  self::g(new self::C::•(#C1));
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = static-tearoff self::h
+}
diff --git a/pkg/front_end/testcases/runtime_checks/field_forwarding_stub_generic_covariant.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/field_forwarding_stub_generic_covariant.dart.weak.modular.expect
new file mode 100644
index 0000000..e0143ec
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/field_forwarding_stub_generic_covariant.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::B::T* x = null;
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  field core::num* x = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C implements self::B<core::num*> {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  forwarding-stub set x(covariant-by-class core::num* value) → void
+    return super.{self::C::x} = value;
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks/forwarding_stub_with_default_values.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/forwarding_stub_with_default_values.dart.weak.modular.expect
new file mode 100644
index 0000000..672eea9
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/forwarding_stub_with_default_values.dart.weak.modular.expect
@@ -0,0 +1,70 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  field core::Object* _x = null;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method f([core::num* x = #C1]) → void {
+    this.{self::B::_x} = x;
+  }
+  method g({core::num* x = #C2}) → void {
+    this.{self::B::_x} = x;
+  }
+  method check(core::Object* expectedValue) → void {
+    if(!(this.{self::B::_x}{core::Object*} =={core::Object::==}{(core::Object*) →* core::bool*} expectedValue)) {
+      throw "Expected _x == ${expectedValue}; got ${this.{self::B::_x}{core::Object*}}";
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::T*>*
+    : super core::Object::•()
+    ;
+  abstract method f([covariant-by-class self::I::T* x = #C3]) → void;
+  abstract method g({covariant-by-class self::I::T* x = #C3}) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B implements self::I<core::num*> {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  forwarding-stub method f([covariant-by-class core::num* x = #C1]) → void
+    return super.{self::B::f}(x);
+  forwarding-stub method g({covariant-by-class core::num* x = #C2}) → void
+    return super.{self::B::g}(x: x);
+}
+static method main() → dynamic {
+  self::C* c = new self::C::•();
+  c.{self::C::f}(){([core::num*]) →* void};
+  c.{self::B::check}(10){(core::Object*) →* void};
+  c.{self::C::g}(){({x: core::num*}) →* void};
+  c.{self::B::check}(20){(core::Object*) →* void};
+}
+
+constants  {
+  #C1 = 10
+  #C2 = 20
+  #C3 = null
+}
diff --git a/pkg/front_end/testcases/runtime_checks/forwarding_stub_with_non_covariant_param.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/forwarding_stub_with_non_covariant_param.dart.weak.modular.expect
new file mode 100644
index 0000000..76facc74
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/forwarding_stub_with_non_covariant_param.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method f(core::int* x, core::int* y) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::T*>*
+    : super core::Object::•()
+    ;
+  abstract method f(covariant-by-class self::I::T* x, core::int* y) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B implements self::I<core::int*> {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  forwarding-stub method f(covariant-by-class core::int* x, core::int* y) → void
+    return super.{self::B::f}(x, y);
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks/generic_covariance_inheritance_setter_field.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/generic_covariance_inheritance_setter_field.dart.weak.modular.expect
new file mode 100644
index 0000000..2fc5b5a
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/generic_covariance_inheritance_setter_field.dart.weak.modular.expect
@@ -0,0 +1,58 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::C::T* y = null;
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  set x(covariant-by-class self::C::T* t) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends core::Object implements self::C<core::num*> {
+  covariant-by-class field core::num* x = null;
+  covariant-by-class field core::num* y = null;
+  synthetic constructor •() → self::D*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class E extends core::Object implements self::C<core::num*> {
+  synthetic constructor •() → self::E*
+    : super core::Object::•()
+    ;
+  set x(covariant-by-class core::num* t) → void {}
+  get y() → core::num*
+    return null;
+  set y(covariant-by-class core::num* t) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks/generic_vs_explicit_covariance.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/generic_vs_explicit_covariance.dart.weak.modular.expect
new file mode 100644
index 0000000..3e9000d
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/generic_vs_explicit_covariance.dart.weak.modular.expect
@@ -0,0 +1,55 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+abstract class A extends core::Object {
+  synthetic constructor •() → self::A*
+    : super core::Object::•()
+    ;
+  abstract set x(covariant-by-declaration core::Object* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class B extends core::Object implements self::A {
+  covariant-by-declaration field core::Object* x = null;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method f(covariant-by-declaration core::Object* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<T extends core::Object* = dynamic> extends core::Object implements self::B {
+  covariant-by-declaration covariant-by-class field self::C::T* x = null;
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method f(covariant-by-declaration covariant-by-class self::C::T* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks/implicit_downcast_assert_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/implicit_downcast_assert_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..c72954d
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/implicit_downcast_assert_initializer.dart.weak.modular.expect
@@ -0,0 +1,28 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  constructor •(core::Object* o) → self::C*
+    : assert(o as{TypeError} core::bool*), super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::Object* o = 1;
+  try {
+    new self::C::•(o);
+    assert(false, "no exception");
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
diff --git a/pkg/front_end/testcases/runtime_checks/implicit_downcast_assert_statement.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/implicit_downcast_assert_statement.dart.weak.modular.expect
new file mode 100644
index 0000000..c4e012c
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/implicit_downcast_assert_statement.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::Object* o = 1;
+  try {
+    assert(o as{TypeError} core::bool*);
+    assert(false, "no exception");
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
diff --git a/pkg/front_end/testcases/runtime_checks/implicit_downcast_constructor_initializer.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/implicit_downcast_constructor_initializer.dart.weak.modular.expect
new file mode 100644
index 0000000..f33aa41
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/implicit_downcast_constructor_initializer.dart.weak.modular.expect
@@ -0,0 +1,29 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  field core::bool* b;
+  constructor •(core::Object* o) → self::C*
+    : self::C::b = o as{TypeError} core::bool*, super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {
+  core::Object* o = 1;
+  try {
+    new self::C::•(o);
+    throw "no exception";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
diff --git a/pkg/front_end/testcases/runtime_checks/implicit_downcast_do.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/implicit_downcast_do.dart.weak.modular.expect
new file mode 100644
index 0000000..21783cf
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/implicit_downcast_do.dart.weak.modular.expect
@@ -0,0 +1,15 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::Object* o = 1;
+  try {
+    do {
+    }
+    while (o as{TypeError} core::bool*)
+    throw "no exception";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
diff --git a/pkg/front_end/testcases/runtime_checks/implicit_downcast_for_condition.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/implicit_downcast_for_condition.dart.weak.modular.expect
new file mode 100644
index 0000000..40fe0be
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/implicit_downcast_for_condition.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → void {
+  core::Object* o = 1;
+  try {
+    for (core::int* i = 0; o as{TypeError} core::bool*; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+    }
+    throw "no exception";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
diff --git a/pkg/front_end/testcases/runtime_checks/implicit_downcast_if.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/implicit_downcast_if.dart.weak.modular.expect
new file mode 100644
index 0000000..dae4331
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/implicit_downcast_if.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::Object* o = 1;
+  try {
+    if(o as{TypeError} core::bool*) {
+    }
+    throw "no exception";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
diff --git a/pkg/front_end/testcases/runtime_checks/implicit_downcast_not.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/implicit_downcast_not.dart.weak.modular.expect
new file mode 100644
index 0000000..84171e4
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/implicit_downcast_not.dart.weak.modular.expect
@@ -0,0 +1,13 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → void {
+  core::Object* o = 1;
+  try {
+    !(o as{TypeError} core::bool*);
+    throw "no exception";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
diff --git a/pkg/front_end/testcases/runtime_checks/implicit_downcast_while.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks/implicit_downcast_while.dart.weak.modular.expect
new file mode 100644
index 0000000..f63e717
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks/implicit_downcast_while.dart.weak.modular.expect
@@ -0,0 +1,14 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::Object* o = 1;
+  try {
+    while (o as{TypeError} core::bool*) {
+    }
+    throw "no exception";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
diff --git a/pkg/front_end/testcases/runtime_checks_new/abstract_override_becomes_forwarding_stub.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/abstract_override_becomes_forwarding_stub.dart.weak.modular.expect
new file mode 100644
index 0000000..761e51b
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/abstract_override_becomes_forwarding_stub.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method f(core::num* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::T*>*
+    : super core::Object::•()
+    ;
+  abstract method f(covariant-by-class self::I::T* x) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B implements self::I<core::num*> {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  forwarding-stub forwarding-semi-stub method f(covariant-by-class core::num* x) → void
+    return super.{self::B::f}(x);
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks_new/call_through_this.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/call_through_this.dart.weak.modular.expect
new file mode 100644
index 0000000..1efedac
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/call_through_this.dart.weak.modular.expect
@@ -0,0 +1,49 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* dynamic;
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  method f(covariant-by-class self::C::T* x) → void {}
+  method g1(covariant-by-class self::C::T* x) → void {
+    this.{self::C::f}(x){(self::C::T*) →* void};
+  }
+  method g2(covariant-by-class self::C::T* x) → void {
+    this.{self::C::f}(x){(self::C::T*) →* void};
+  }
+  method g3(covariant-by-class self::C<self::C::T*>* c, covariant-by-class self::C::T* x) → void {
+    c.{self::C::f}(x){(self::C::T*) →* void};
+  }
+  method g4() → (self::C::T*) →* dynamic
+    return this.{self::C::f}{(self::C::T*) →* void};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C<core::int*> {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+}
+class E extends self::C<core::num*> {
+  synthetic constructor •() → self::E*
+    : super self::C::•()
+    ;
+  method f(covariant-by-declaration covariant-by-class core::int* x) → void {}
+}
+static method test() → dynamic {
+  (core::Object*) →* dynamic x = (new self::D::•().{self::C::g4}(){() →* (core::int*) →* dynamic} as{TypeError,CovarianceCheck} (core::int*) →* dynamic) as (core::Object*) →* dynamic;
+  x("hi"){(core::Object*) →* dynamic};
+  new self::E::•().{self::C::g1}(1.5){(core::num*) →* void};
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks_new/contravariant_combiner.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/contravariant_combiner.dart.weak.modular.expect
new file mode 100644
index 0000000..d266b53
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/contravariant_combiner.dart.weak.modular.expect
@@ -0,0 +1,59 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+class B<T extends core::Object* = dynamic, U extends (self::B::T*) →* void = (Null) →* void> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*, self::B::U*>*
+    : super core::Object::•()
+    ;
+  operator +(dynamic other) → self::B<self::B::T*, (self::B::T*) →* void>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  field self::B<core::num*, (core::num*) →* void>* x = null;
+  static field self::B<core::num*, (core::num*) →* void>* y = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  operator [](core::int* i) → self::B<core::num*, (core::num*) →* void>*
+    return null;
+  operator []=(core::int* i, self::B<core::num*, (core::num*) →* void>* v) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test1(self::B<core::num*, (core::num*) →* void>* b) → void {
+  b = b.{self::B::+}(1){(dynamic) →* self::B<core::num*, (core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<core::num*, (core::num*) →* void>*;
+  self::B<core::num*, (core::num*) →* void>* x = b = b.{self::B::+}(2){(dynamic) →* self::B<core::num*, (core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<core::num*, (core::num*) →* void>*;
+}
+static method test2(self::C* c) → void {
+  let final self::C* #t1 = c in let final core::int* #t2 = 0 in #t1.{self::C::[]=}(#t2, #t1.{self::C::[]}(#t2){(core::int*) →* self::B<core::num*, (core::num*) →* void>*}.{self::B::+}(1){(dynamic) →* self::B<core::num*, (core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<core::num*, (core::num*) →* void>*){(core::int*, self::B<core::num*, (core::num*) →* void>*) →* void};
+  self::B<core::num*, (core::num*) →* void>* x = let final self::C* #t3 = c in let final core::int* #t4 = 0 in let final self::B<core::num*, (core::num*) →* void>* #t5 = #t3.{self::C::[]}(#t4){(core::int*) →* self::B<core::num*, (core::num*) →* void>*}.{self::B::+}(2){(dynamic) →* self::B<core::num*, (core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<core::num*, (core::num*) →* void>* in let final void #t6 = #t3.{self::C::[]=}(#t4, #t5){(core::int*, self::B<core::num*, (core::num*) →* void>*) →* void} in #t5;
+}
+static method test3(self::C* c) → void {
+  let final self::C* #t7 = c in #t7.{self::C::x} = #t7.{self::C::x}{self::B<core::num*, (core::num*) →* void>*}.{self::B::+}(1){(dynamic) →* self::B<core::num*, (core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<core::num*, (core::num*) →* void>*;
+  self::B<core::num*, (core::num*) →* void>* x = let final self::C* #t8 = c in #t8.{self::C::x} = #t8.{self::C::x}{self::B<core::num*, (core::num*) →* void>*}.{self::B::+}(2){(dynamic) →* self::B<core::num*, (core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<core::num*, (core::num*) →* void>*;
+}
+static method test4(self::C* c) → void {
+  self::C::y = self::C::y.{self::B::+}(1){(dynamic) →* self::B<core::num*, (core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<core::num*, (core::num*) →* void>*;
+  self::B<core::num*, (core::num*) →* void>* x = self::C::y = self::C::y.{self::B::+}(2){(dynamic) →* self::B<core::num*, (core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<core::num*, (core::num*) →* void>*;
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks_new/contravariant_generic_return_with_compound_assign_implicit_downcast.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/contravariant_generic_return_with_compound_assign_implicit_downcast.dart.weak.modular.expect
new file mode 100644
index 0000000..edcb17e
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/contravariant_generic_return_with_compound_assign_implicit_downcast.dart.weak.modular.expect
@@ -0,0 +1,99 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/runtime_checks_new/contravariant_generic_return_with_compound_assign_implicit_downcast.dart:30:14: Error: The type 'C<num>' of the getter 'D.value' is not assignable to the type 'int Function(int)' of the setter 'D.value'.
+//  - 'C' is from 'pkg/front_end/testcases/runtime_checks_new/contravariant_generic_return_with_compound_assign_implicit_downcast.dart'.
+//   C<num> get value => getValue;
+//              ^^^^^
+// pkg/front_end/testcases/runtime_checks_new/contravariant_generic_return_with_compound_assign_implicit_downcast.dart:32:12: Context: This is the declaration of the setter 'D.value'.
+//   void set value(int Function(int) value) {
+//            ^^^^^
+//
+// pkg/front_end/testcases/runtime_checks_new/contravariant_generic_return_with_compound_assign_implicit_downcast.dart:49:46: Error: A value of type 'num Function(num)' can't be assigned to a variable of type 'int Function(int)'.
+//   d.value /*@ checkReturn=(num*) ->* num* */ += 1;
+//                                              ^
+//
+// pkg/front_end/testcases/runtime_checks_new/contravariant_generic_return_with_compound_assign_implicit_downcast.dart:53:48: Error: A value of type 'num Function(num)' can't be assigned to a variable of type 'int Function(int)'.
+//     d.value /*@ checkReturn=(num*) ->* num* */ += 1;
+//                                                ^
+//
+import self as self;
+import "dart:core" as core;
+
+class C<T extends core::Object* = dynamic> extends core::Object {
+  final field (self::C::T*) →* core::num* plusResult;
+  constructor •((self::C::T*) →* core::num* plusResult) → self::C<self::C::T*>*
+    : self::C::plusResult = plusResult, super core::Object::•()
+    ;
+  operator +(core::int* i) → (self::C::T*) →* core::num*
+    return this.{self::C::plusResult}{(self::C::T*) →* core::num*};
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends core::Object {
+  final field self::C<core::num*>* getValue;
+  field (core::int*) →* core::int* setValue = null;
+  constructor •(self::C<core::num*>* getValue) → self::D*
+    : self::D::getValue = getValue, super core::Object::•()
+    ;
+  get value() → self::C<core::num*>*
+    return this.{self::D::getValue}{self::C<core::num*>*};
+  set value((core::int*) →* core::int* value) → void {
+    this.{self::D::setValue} = value;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method expectTypeError(() →* void callback) → void {
+  try {
+    callback(){() →* void};
+    throw "Expected TypeError, did not occur";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
+static method expect(core::Object* value, core::Object* expected) → void {
+  if(!(value =={core::Object::==}{(core::Object*) →* core::bool*} expected)) {
+    throw "Expected ${expected}, got ${value}";
+  }
+}
+static method numToInt(core::num* n) → core::int*
+  return 1;
+static method numToNum(core::num* n) → core::num*
+  return 2;
+static method main() → void {
+  self::D* d = new self::D::•(new self::C::•<core::num*>(#C1));
+  let final self::D* #t1 = d in #t1.{self::D::value} = invalid-expression "pkg/front_end/testcases/runtime_checks_new/contravariant_generic_return_with_compound_assign_implicit_downcast.dart:49:46: Error: A value of type 'num Function(num)' can't be assigned to a variable of type 'int Function(int)'.
+  d.value /*@ checkReturn=(num*) ->* num* */ += 1;
+                                             ^" in (#t1.{self::D::value}{self::C<core::num*>*}.{self::C::+}(1){(core::int*) →* (core::num*) →* core::num*} as{TypeError,CovarianceCheck} (core::num*) →* core::num*) as{TypeError} (core::int*) →* core::int*;
+  self::expect(let final self::D* #t2 = d in let final core::int* #t3 = 0 in #t2.{self::D::setValue}{(core::int*) →* core::int*}(#t3){(core::int*) →* core::int*}, 1);
+  d = new self::D::•(new self::C::•<core::num*>(#C2));
+  self::expectTypeError(() → Null {
+    let final self::D* #t4 = d in #t4.{self::D::value} = invalid-expression "pkg/front_end/testcases/runtime_checks_new/contravariant_generic_return_with_compound_assign_implicit_downcast.dart:53:48: Error: A value of type 'num Function(num)' can't be assigned to a variable of type 'int Function(int)'.
+    d.value /*@ checkReturn=(num*) ->* num* */ += 1;
+                                               ^" in (#t4.{self::D::value}{self::C<core::num*>*}.{self::C::+}(1){(core::int*) →* (core::num*) →* core::num*} as{TypeError,CovarianceCheck} (core::num*) →* core::num*) as{TypeError} (core::int*) →* core::int*;
+  });
+  self::expect(d.{self::D::setValue}{(core::int*) →* core::int*}, null);
+}
+
+constants  {
+  #C1 = static-tearoff self::numToInt
+  #C2 = static-tearoff self::numToNum
+}
diff --git a/pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart.weak.modular.expect
new file mode 100644
index 0000000..c730f2f
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart.weak.modular.expect
@@ -0,0 +1,82 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart:20:54: Error: A value of type 'B<num>' can't be assigned to a variable of type 'B<void Function(num)>'.
+//  - 'B' is from 'pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart'.
+//   c. /*@ checkReturn=B<(num*) ->* void>* */ x += new B<num>();
+//                                                      ^
+//
+// pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart:21:62: Error: A value of type 'B<num>' can't be assigned to a variable of type 'B<void Function(num)>'.
+//  - 'B' is from 'pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart'.
+//   var y = c. /*@ checkReturn=B<(num*) ->* void>* */ x += new B<num>();
+//                                                              ^
+//
+// pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart:22:55: Error: A value of type 'B<num>' can't be assigned to a variable of type 'B<void Function(num)>'.
+//  - 'B' is from 'pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart'.
+//   c. /*@ checkReturn=B<(num*) ->* void>* */ x ??= new B<num>();
+//                                                       ^
+//
+// pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart:23:63: Error: A value of type 'B<num>' can't be assigned to a variable of type 'B<void Function(num)>'.
+//  - 'B' is from 'pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart'.
+//   var z = c. /*@ checkReturn=B<(num*) ->* void>* */ x ??= new B<num>();
+//                                                               ^
+//
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+class B<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  operator +(covariant-by-class self::B<self::B::T*>* other) → self::B<self::B::T*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  get x() → self::B<(self::C::T*) →* void>*
+    return null;
+  set x(self::B<(self::C::T*) →* void>* value) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test(self::C<core::num*>* c) → void {
+  let final self::C<core::num*>* #t1 = c in #t1.{self::C::x} = (#t1.{self::C::x}{self::B<(core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<(core::num*) →* void>*).{self::B::+}(invalid-expression "pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart:20:54: Error: A value of type 'B<num>' can't be assigned to a variable of type 'B<void Function(num)>'.
+ - 'B' is from 'pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart'.
+  c. /*@ checkReturn=B<(num*) ->* void>* */ x += new B<num>();
+                                                     ^" in new self::B::•<core::num*>() as{TypeError} self::B<(core::num*) →* void>*){(self::B<(core::num*) →* void>*) →* self::B<(core::num*) →* void>*};
+  self::B<(core::num*) →* void>* y = let final self::C<core::num*>* #t2 = c in #t2.{self::C::x} = (#t2.{self::C::x}{self::B<(core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<(core::num*) →* void>*).{self::B::+}(invalid-expression "pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart:21:62: Error: A value of type 'B<num>' can't be assigned to a variable of type 'B<void Function(num)>'.
+ - 'B' is from 'pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart'.
+  var y = c. /*@ checkReturn=B<(num*) ->* void>* */ x += new B<num>();
+                                                             ^" in new self::B::•<core::num*>() as{TypeError} self::B<(core::num*) →* void>*){(self::B<(core::num*) →* void>*) →* self::B<(core::num*) →* void>*};
+  let final self::C<core::num*>* #t3 = c in #t3.{self::C::x}{self::B<(core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<(core::num*) →* void>* == null ?{self::B<core::Object*>*} #t3.{self::C::x} = invalid-expression "pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart:22:55: Error: A value of type 'B<num>' can't be assigned to a variable of type 'B<void Function(num)>'.
+ - 'B' is from 'pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart'.
+  c. /*@ checkReturn=B<(num*) ->* void>* */ x ??= new B<num>();
+                                                      ^" in new self::B::•<core::num*>() as{TypeError} self::B<(core::num*) →* void>* : null;
+  self::B<core::Object*>* z = let final self::C<core::num*>* #t4 = c in let final self::B<(core::num*) →* void>* #t5 = #t4.{self::C::x}{self::B<(core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<(core::num*) →* void>* in #t5 == null ?{self::B<core::Object*>*} #t4.{self::C::x} = invalid-expression "pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart:23:63: Error: A value of type 'B<num>' can't be assigned to a variable of type 'B<void Function(num)>'.
+ - 'B' is from 'pkg/front_end/testcases/runtime_checks_new/contravariant_getter_return_compound_assign.dart'.
+  var z = c. /*@ checkReturn=B<(num*) ->* void>* */ x ??= new B<num>();
+                                                              ^" in new self::B::•<core::num*>() as{TypeError} self::B<(core::num*) →* void>* : #t5;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks_new/contravariant_index_assign.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/contravariant_index_assign.dart.weak.modular.expect
new file mode 100644
index 0000000..3769315
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/contravariant_index_assign.dart.weak.modular.expect
@@ -0,0 +1,48 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+class B<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  operator +(covariant-by-class self::B<self::B::T*>* other) → self::B<self::B::T*>*
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  operator [](core::int* i) → self::B<(self::C::T*) →* void>*
+    return null;
+  operator []=(core::int* i, self::B<(self::C::T*) →* void>* x) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test(self::C<core::num*>* c) → void {
+  c.{self::C::[]=}(0, new self::B::•<(core::num*) →* void>()){(core::int*, self::B<(core::num*) →* void>*) →* void};
+  let final self::C<core::num*>* #t1 = c in let final core::int* #t2 = 0 in #t1.{self::C::[]=}(#t2, (#t1.{self::C::[]}(#t2){(core::int*) →* self::B<(core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<(core::num*) →* void>*).{self::B::+}(new self::B::•<(core::num*) →* void>()){(self::B<(core::num*) →* void>*) →* self::B<(core::num*) →* void>*}){(core::int*, self::B<(core::num*) →* void>*) →* void};
+  self::B<(core::num*) →* void>* x = let final self::C<core::num*>* #t3 = c in let final core::int* #t4 = 0 in let final self::B<(core::num*) →* void>* #t5 = (#t3.{self::C::[]}(#t4){(core::int*) →* self::B<(core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<(core::num*) →* void>*).{self::B::+}(new self::B::•<(core::num*) →* void>()){(self::B<(core::num*) →* void>*) →* self::B<(core::num*) →* void>*} in let final void #t6 = #t3.{self::C::[]=}(#t4, #t5){(core::int*, self::B<(core::num*) →* void>*) →* void} in #t5;
+  let final self::C<core::num*>* #t7 = c in let final core::int* #t8 = 0 in #t7.{self::C::[]}(#t8){(core::int*) →* self::B<(core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<(core::num*) →* void>* == null ?{self::B<(core::num*) →* void>*} #t7.{self::C::[]=}(#t8, new self::B::•<(core::num*) →* void>()){(core::int*, self::B<(core::num*) →* void>*) →* void} : null;
+  self::B<(core::num*) →* void>* y = let final self::C<core::num*>* #t9 = c in let final core::int* #t10 = 0 in let final self::B<(core::num*) →* void>* #t11 = #t9.{self::C::[]}(#t10){(core::int*) →* self::B<(core::num*) →* void>*} as{TypeError,CovarianceCheck} self::B<(core::num*) →* void>* in #t11 == null ?{self::B<(core::num*) →* void>*} let final self::B<(core::num*) →* void>* #t12 = new self::B::•<(core::num*) →* void>() in let final void #t13 = #t9.{self::C::[]=}(#t10, #t12){(core::int*, self::B<(core::num*) →* void>*) →* void} in #t12 : #t11;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks_new/contravariant_index_get.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/contravariant_index_get.dart.weak.modular.expect
new file mode 100644
index 0000000..906d2cb
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/contravariant_index_get.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+typedef F<contravariant T extends core::Object* = dynamic> = (T*) →* void;
+class C<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  operator [](core::int* i) → (self::C::T*) →* void
+    return null;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method test(self::C<core::num*>* c) → (core::num*) →* void {
+  return c.{self::C::[]}(0){(core::int*) →* (core::num*) →* void} as{TypeError,CovarianceCheck} (core::num*) →* void;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks_new/derived_class_typed.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/derived_class_typed.dart.weak.modular.expect
new file mode 100644
index 0000000..80e45ff
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/derived_class_typed.dart.weak.modular.expect
@@ -0,0 +1,41 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  method f(covariant-by-class self::B::T* x) → void {}
+  method g({covariant-by-class self::B::T* x = #C1}) → void {}
+  method h<covariant-by-class U extends self::B::T*>() → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B<core::int*> {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+static method g1(self::B<core::num*>* b) → void {
+  b.{self::B::f}(1.5){(core::num*) →* void};
+}
+static method g2(self::C* c) → void {
+  c.{self::B::f}(1){(core::int*) →* void};
+}
+static method test() → void {
+  self::g1(new self::C::•());
+}
+static method main() → void {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/runtime_checks_new/field_forwarding_stub_abstract_generic_covariant.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/field_forwarding_stub_abstract_generic_covariant.dart.weak.modular.expect
new file mode 100644
index 0000000..985b00d
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/field_forwarding_stub_abstract_generic_covariant.dart.weak.modular.expect
@@ -0,0 +1,26 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::B::T* x = null;
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B<core::num*> {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks_new/field_forwarding_stub_explicit_covariant.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/field_forwarding_stub_explicit_covariant.dart.weak.modular.expect
new file mode 100644
index 0000000..ec01d37
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/field_forwarding_stub_explicit_covariant.dart.weak.modular.expect
@@ -0,0 +1,57 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/runtime_checks_new/field_forwarding_stub_explicit_covariant.dart:16:7: Error: The implementation of 'x' in the non-abstract class 'D' does not conform to its interface.
+// class D extends C implements B {}
+//       ^
+// pkg/front_end/testcases/runtime_checks_new/field_forwarding_stub_explicit_covariant.dart:13:7: Context: The field 'C.x' has type 'int', which does not match the corresponding type, 'num', in the overridden setter, 'D.x'.
+//   int x;
+//       ^
+// pkg/front_end/testcases/runtime_checks_new/field_forwarding_stub_explicit_covariant.dart:16:7: Context: This is the overridden method ('x').
+// class D extends C implements B {}
+//       ^
+//
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  covariant-by-declaration field core::num* x = null;
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends core::Object {
+  field core::int* x = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class D extends self::C implements self::B {
+  synthetic constructor •() → self::D*
+    : super self::C::•()
+    ;
+  forwarding-stub set x(covariant-by-declaration core::num* value) → void
+    return super.{self::C::x} = value as core::int*;
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks_new/for_in_call_kinds.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/for_in_call_kinds.dart.weak.modular.expect
new file mode 100644
index 0000000..05fc7de
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/for_in_call_kinds.dart.weak.modular.expect
@@ -0,0 +1,50 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field dynamic staticField = null;
+  field dynamic instanceField = null;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  static set staticSetter(dynamic x) → void {}
+  set instanceSetter(dynamic x) → void {}
+  method test() → void {
+    dynamic localVar;
+    for (final dynamic #t1 in <dynamic>[]) {
+      self::topLevel = #t1;
+    }
+    for (final dynamic #t2 in <dynamic>[]) {
+      self::topLevelSetter = #t2;
+    }
+    for (final dynamic #t3 in <dynamic>[]) {
+      self::C::staticField = #t3;
+    }
+    for (final dynamic #t4 in <dynamic>[]) {
+      self::C::staticSetter = #t4;
+    }
+    for (final dynamic #t5 in <dynamic>[]) {
+      this.{self::C::instanceField} = #t5;
+    }
+    for (final dynamic #t6 in <dynamic>[]) {
+      this.{self::C::instanceSetter} = #t6;
+    }
+    for (final dynamic #t7 in <dynamic>[]) {
+      localVar = #t7;
+    }
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field dynamic topLevel;
+static set topLevelSetter(dynamic x) → void {}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks_new/generic_covariance_based_on_inference.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/generic_covariance_based_on_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..7bfe030
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/generic_covariance_based_on_inference.dart.weak.modular.expect
@@ -0,0 +1,58 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B<T extends core::Object* = dynamic> extends core::Object {
+  covariant-by-class field self::B::T* x = null;
+  covariant-by-class field self::B::T* y = null;
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C<T extends core::Object* = dynamic> extends core::Object implements self::B<core::num*> {
+  covariant-by-class field core::num* x = null;
+  synthetic constructor •() → self::C<self::C::T*>*
+    : super core::Object::•()
+    ;
+  abstract get y() → core::num*;
+  abstract set y(covariant-by-class core::num* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class D<T extends core::Object* = dynamic> extends core::Object implements self::B<self::D::T*> {
+  covariant-by-class field self::D::T* x = null;
+  synthetic constructor •() → self::D<self::D::T*>*
+    : super core::Object::•()
+    ;
+  abstract get y() → self::D::T*;
+  abstract set y(covariant-by-class self::D::T* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/runtime_checks_new/implicit_downcast_field.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/implicit_downcast_field.dart.weak.modular.expect
new file mode 100644
index 0000000..0fdb717
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/implicit_downcast_field.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class C extends core::Object {
+  static field core::bool* staticValue = self::o as{TypeError} core::bool*;
+  field core::bool* instanceValue = self::o as{TypeError} core::bool*;
+  synthetic constructor •() → self::C*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field core::Object* o = 1;
+static field core::bool* topLevelValue = self::o as{TypeError} core::bool*;
+static method main() → dynamic {
+  try {
+    self::topLevelValue;
+    throw "no exception";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+  try {
+    self::C::staticValue;
+    throw "no exception";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+  try {
+    new self::C::•();
+    throw "no exception";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
diff --git a/pkg/front_end/testcases/runtime_checks_new/mixin_forwarding_stub_field.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/mixin_forwarding_stub_field.dart.weak.modular.expect
new file mode 100644
index 0000000..99c30ab
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/mixin_forwarding_stub_field.dart.weak.modular.expect
@@ -0,0 +1,122 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/runtime_checks_new/mixin_forwarding_stub_field.dart:51:7: Error: The mixin application class 'C' introduces an erroneous override of 'y'.
+// class C = B with M implements I<int>;
+//       ^
+// pkg/front_end/testcases/runtime_checks_new/mixin_forwarding_stub_field.dart:48:7: Context: The field 'M.y' has type 'int', which does not match the corresponding type, 'Object', in the overridden setter, 'I.y'.
+//  - 'Object' is from 'dart:core'.
+//   int y;
+//       ^
+// pkg/front_end/testcases/runtime_checks_new/mixin_forwarding_stub_field.dart:43:12: Context: This is the overridden method ('y').
+//   void set y(covariant Object value);
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  get x() → core::int* {
+    throw "Should not be reached";
+  }
+  set x(core::int* value) → void {
+    throw "Should not be reached";
+  }
+  get y() → core::int* {
+    throw "Should not be reached";
+  }
+  set y(core::int* value) → void {
+    throw "Should not be reached";
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::T*>*
+    : super core::Object::•()
+    ;
+  abstract get x() → self::I::T*;
+  abstract set x(covariant-by-class self::I::T* value) → void;
+  abstract get y() → core::Object*;
+  abstract set y(covariant-by-declaration core::Object* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M extends core::Object {
+  field core::int* x = null;
+  field core::int* y = null;
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C = self::B with self::M implements self::I<core::int*> {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  mixin-super-stub get x() → core::int*
+    return super.{self::M::x};
+  forwarding-stub set x(covariant-by-class core::int* value) → void
+    return super.{self::M::x} = value;
+  mixin-super-stub get y() → core::int*
+    return super.{self::M::y};
+  forwarding-stub set y(covariant-by-declaration core::int* value) → void
+    return super.{self::M::y} = value;
+}
+static method expectTypeError(() →* void callback) → void {
+  try {
+    callback(){() →* void};
+    throw "Expected TypeError, did not occur";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
+static method expect(core::Object* value, core::Object* expected) → void {
+  if(!(value =={core::Object::==}{(core::Object*) →* core::bool*} expected)) {
+    throw "Expected ${expected}, got ${value}";
+  }
+}
+static method test(self::I<core::Object*>* i) → void {
+  self::expectTypeError(() → Null {
+    i.{self::I::x} = "hello";
+  });
+  i.{self::I::x} = 1;
+  self::expect(i.{self::I::x}{core::Object*}, 1);
+  self::expectTypeError(() → Null {
+    i.{self::I::y} = "hello";
+  });
+  i.{self::I::y} = 2;
+  self::expect(i.{self::I::y}{core::Object*}, 2);
+}
+static method main() → void {
+  self::test(new self::C::•());
+}
diff --git a/pkg/front_end/testcases/runtime_checks_new/mixin_forwarding_stub_setter.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/mixin_forwarding_stub_setter.dart.weak.modular.expect
new file mode 100644
index 0000000..83a8031
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/mixin_forwarding_stub_setter.dart.weak.modular.expect
@@ -0,0 +1,131 @@
+library test;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/runtime_checks_new/mixin_forwarding_stub_setter.dart:58:7: Error: The mixin application class 'C' introduces an erroneous override of 'y'.
+// class C = B with M implements I<int>;
+//       ^
+// pkg/front_end/testcases/runtime_checks_new/mixin_forwarding_stub_setter.dart:53:18: Context: The parameter 'value' of the method 'M.y' has type 'int', which does not match the corresponding type, 'Object', in the overridden method, 'I.y'.
+//  - 'Object' is from 'dart:core'.
+// Change to a supertype of 'Object', or, for a covariant parameter, a subtype.
+//   void set y(int value) {
+//                  ^
+// pkg/front_end/testcases/runtime_checks_new/mixin_forwarding_stub_setter.dart:43:12: Context: This is the overridden method ('y').
+//   void set y(covariant Object value);
+//            ^
+//
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  get x() → core::int* {
+    throw "Should not be reached";
+  }
+  set x(core::int* value) → void {
+    throw "Should not be reached";
+  }
+  get y() → core::int* {
+    throw "Should not be reached";
+  }
+  set y(core::int* value) → void {
+    throw "Should not be reached";
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::T*>*
+    : super core::Object::•()
+    ;
+  abstract get x() → self::I::T*;
+  abstract set x(covariant-by-class self::I::T* value) → void;
+  abstract get y() → core::Object*;
+  abstract set y(covariant-by-declaration core::Object* value) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class M extends core::Object {
+  synthetic constructor •() → self::M*
+    : super core::Object::•()
+    ;
+  get x() → core::int*
+    return 1;
+  set x(core::int* value) → void {
+    self::expect(value, 2);
+  }
+  get y() → core::int*
+    return 3;
+  set y(core::int* value) → void {
+    self::expect(value, 4);
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C = self::B with self::M implements self::I<core::int*> {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  mixin-super-stub get x() → core::int*
+    return super.{self::M::x};
+  forwarding-stub set x(covariant-by-class core::int* value) → void
+    return super.{self::M::x} = value;
+  mixin-super-stub get y() → core::int*
+    return super.{self::M::y};
+  forwarding-stub set y(covariant-by-declaration core::int* value) → void
+    return super.{self::M::y} = value;
+}
+static method expectTypeError(() →* void callback) → void {
+  try {
+    callback(){() →* void};
+    throw "Expected TypeError, did not occur";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
+static method expect(core::Object* value, core::Object* expected) → void {
+  if(!(value =={core::Object::==}{(core::Object*) →* core::bool*} expected)) {
+    throw "Expected ${expected}, got ${value}";
+  }
+}
+static method test(self::I<core::Object*>* i) → void {
+  self::expectTypeError(() → Null {
+    i.{self::I::x} = "hello";
+  });
+  i.{self::I::x} = 2;
+  self::expect(i.{self::I::x}{core::Object*}, 1);
+  self::expectTypeError(() → Null {
+    i.{self::I::y} = "hello";
+  });
+  i.{self::I::y} = 4;
+  self::expect(i.{self::I::y}{core::Object*}, 3);
+}
+static method main() → void {
+  self::test(new self::C::•());
+}
diff --git a/pkg/front_end/testcases/runtime_checks_new/stub_checked_via_target.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/stub_checked_via_target.dart.weak.modular.expect
new file mode 100644
index 0000000..0fc6d13
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/stub_checked_via_target.dart.weak.modular.expect
@@ -0,0 +1,76 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method f(core::int* x) → core::int* {
+    self::expect(x, 1);
+    return 2;
+  }
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  abstract method f(covariant-by-declaration core::Object* x) → core::int*;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+class C extends self::B implements self::I {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  forwarding-stub method f(covariant-by-declaration core::Object* x) → core::int*
+    return super.{self::B::f}(x as core::int*);
+}
+static method expectTypeError(() →* void callback) → void {
+  try {
+    callback(){() →* void};
+    throw "Expected TypeError, did not occur";
+  }
+  on core::TypeError* catch(no-exception-var) {
+  }
+}
+static method expect(core::Object* value, core::Object* expected) → void {
+  if(!(value =={core::Object::==}{(core::Object*) →* core::bool*} expected)) {
+    throw "Expected ${expected}, got ${value}";
+  }
+}
+static method g(self::C* c) → void {
+  c.{self::C::f}("hello"){(core::Object*) →* core::int*};
+}
+static method test(self::C* c, self::I* i) → void {
+  self::expectTypeError(() → Null {
+    i.{self::I::f}("hello"){(core::Object*) →* core::int*};
+  });
+  self::expect(i.{self::I::f}(1){(core::Object*) →* core::int*}, 2);
+  self::expectTypeError(() → Null {
+    c.{self::C::f}("hello"){(core::Object*) →* core::int*};
+  });
+  self::expect(c.{self::C::f}(1){(core::Object*) →* core::int*}, 2);
+}
+static method main() → dynamic {
+  self::C* c = new self::C::•();
+  self::test(c, c);
+}
diff --git a/pkg/front_end/testcases/runtime_checks_new/stub_from_interface_covariantImpl_from_interface.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/stub_from_interface_covariantImpl_from_interface.dart.weak.modular.expect
new file mode 100644
index 0000000..9aacb53
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/stub_from_interface_covariantImpl_from_interface.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method f(core::int* x, core::int* y) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::I<self::I::T*>*
+    : super core::Object::•()
+    ;
+  abstract method f(covariant-by-class self::I::T* x, core::Object* y) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends self::B implements self::I<core::int*> {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  forwarding-stub method f(covariant-by-class core::int* x, core::Object* y) → void
+    return super.{self::B::f}(x, y as core::int*);
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks_new/stub_from_interface_covariantImpl_from_super.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/stub_from_interface_covariantImpl_from_super.dart.weak.modular.expect
new file mode 100644
index 0000000..f0e4b8e
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/stub_from_interface_covariantImpl_from_super.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B<T extends core::Object* = dynamic> extends core::Object {
+  synthetic constructor •() → self::B<self::B::T*>*
+    : super core::Object::•()
+    ;
+  method f(covariant-by-class self::B::T* x, core::int* y) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  abstract method f(core::int* x, core::Object* y) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends self::B<core::int*> implements self::I {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  abstract forwarding-stub method f(covariant-by-class core::int* x, core::Object* y) → void;
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks_new/stub_from_interface_covariant_from_interface.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/stub_from_interface_covariant_from_interface.dart.weak.modular.expect
new file mode 100644
index 0000000..8f7a060
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/stub_from_interface_covariant_from_interface.dart.weak.modular.expect
@@ -0,0 +1,44 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method f(core::int* x, core::int* y) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  abstract method f(covariant-by-declaration core::int* x, core::Object* y) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends self::B implements self::I {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  forwarding-stub method f(covariant-by-declaration core::int* x, core::Object* y) → void
+    return super.{self::B::f}(x, y as core::int*);
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/runtime_checks_new/stub_from_interface_covariant_from_super.dart.weak.modular.expect b/pkg/front_end/testcases/runtime_checks_new/stub_from_interface_covariant_from_super.dart.weak.modular.expect
new file mode 100644
index 0000000..d4b9b44
--- /dev/null
+++ b/pkg/front_end/testcases/runtime_checks_new/stub_from_interface_covariant_from_super.dart.weak.modular.expect
@@ -0,0 +1,43 @@
+library test;
+import self as self;
+import "dart:core" as core;
+
+class B extends core::Object {
+  synthetic constructor •() → self::B*
+    : super core::Object::•()
+    ;
+  method f(covariant-by-declaration core::int* x, core::int* y) → void {}
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class I extends core::Object {
+  synthetic constructor •() → self::I*
+    : super core::Object::•()
+    ;
+  abstract method f(core::int* x, core::Object* y) → void;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+abstract class C extends self::B implements self::I {
+  synthetic constructor •() → self::C*
+    : super self::B::•()
+    ;
+  abstract forwarding-stub method f(covariant-by-declaration core::int* x, core::Object* y) → void;
+}
+static method main() → void {}
diff --git a/pkg/front_end/testcases/set_literals/disambiguation_rule.dart.weak.modular.expect b/pkg/front_end/testcases/set_literals/disambiguation_rule.dart.weak.modular.expect
new file mode 100644
index 0000000..d565d03
--- /dev/null
+++ b/pkg/front_end/testcases/set_literals/disambiguation_rule.dart.weak.modular.expect
@@ -0,0 +1,139 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/set_literals/disambiguation_rule.dart:13:28: Error: The set literal type 'Set<dynamic>' isn't of expected type 'LinkedHashSet<int>'.
+//  - 'Set' is from 'dart:core'.
+//  - 'LinkedHashSet' is from 'dart:collection'.
+// Change the type of the set literal or the context in which it is used.
+//   LinkedHashSet<int> lhs = {};
+//                            ^
+//
+// pkg/front_end/testcases/set_literals/disambiguation_rule.dart:14:34: Error: The map literal type 'Map<dynamic, dynamic>' isn't of expected type 'LinkedHashMap<int, bool>'.
+//  - 'Map' is from 'dart:core'.
+//  - 'LinkedHashMap' is from 'dart:collection'.
+// Change the type of the map literal or the context in which it is used.
+//   LinkedHashMap<int, bool> lhm = {};
+//                                  ^
+//
+// pkg/front_end/testcases/set_literals/disambiguation_rule.dart:32:46: Error: The set literal type 'Future<Set<dynamic>>' isn't of expected type 'Future<LinkedHashSet<int>>'.
+//  - 'Future' is from 'dart:async'.
+//  - 'Set' is from 'dart:core'.
+//  - 'LinkedHashSet' is from 'dart:collection'.
+// Change the type of the set literal or the context in which it is used.
+// Future<LinkedHashSet<int>> lhsfun() async => {};
+//                                              ^
+//
+// pkg/front_end/testcases/set_literals/disambiguation_rule.dart:33:52: Error: The map literal type 'Future<Map<dynamic, dynamic>>' isn't of expected type 'Future<LinkedHashMap<int, bool>>'.
+//  - 'Future' is from 'dart:async'.
+//  - 'Map' is from 'dart:core'.
+//  - 'LinkedHashMap' is from 'dart:collection'.
+// Change the type of the map literal or the context in which it is used.
+// Future<LinkedHashMap<int, bool>> lhmfun() async => {};
+//                                                    ^
+//
+// pkg/front_end/testcases/set_literals/disambiguation_rule.dart:38:43: Error: A value of type 'Set<dynamic>' can't be assigned to a variable of type 'FutureOr<LinkedHashSet<int>>'.
+//  - 'Set' is from 'dart:core'.
+//  - 'LinkedHashSet' is from 'dart:collection'.
+// FutureOr<LinkedHashSet<int>> lhsfun2() => {};
+//                                           ^
+//
+// pkg/front_end/testcases/set_literals/disambiguation_rule.dart:39:49: Error: A value of type 'Map<dynamic, dynamic>' can't be assigned to a variable of type 'FutureOr<LinkedHashMap<int, bool>>'.
+//  - 'Map' is from 'dart:core'.
+//  - 'LinkedHashMap' is from 'dart:collection'.
+// FutureOr<LinkedHashMap<int, bool>> lhmfun2() => {};
+//                                                 ^
+//
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+import "dart:async" as asy;
+
+import "dart:async" show FutureOr;
+import "dart:collection" show LinkedHashMap, LinkedHashSet;
+
+static method main() → dynamic async {
+  core::Map<core::int*, core::bool*>* m = <core::int*, core::bool*>{};
+  core::Set<core::int*>* s = block {
+    final core::Set<core::int*>* #t1 = col::LinkedHashSet::•<core::int*>();
+  } =>#t1;
+  core::Iterable<core::int*>* i = block {
+    final core::Set<core::int*>* #t2 = col::LinkedHashSet::•<core::int*>();
+  } =>#t2;
+  col::LinkedHashSet<core::int*>* lhs = invalid-expression "pkg/front_end/testcases/set_literals/disambiguation_rule.dart:13:28: Error: The set literal type 'Set<dynamic>' isn't of expected type 'LinkedHashSet<int>'.
+ - 'Set' is from 'dart:core'.
+ - 'LinkedHashSet' is from 'dart:collection'.
+Change the type of the set literal or the context in which it is used.
+  LinkedHashSet<int> lhs = {};
+                           ^" in block {
+    final core::Set<dynamic>* #t3 = col::LinkedHashSet::•<dynamic>();
+  } =>#t3;
+  col::LinkedHashMap<core::int*, core::bool*>* lhm = invalid-expression "pkg/front_end/testcases/set_literals/disambiguation_rule.dart:14:34: Error: The map literal type 'Map<dynamic, dynamic>' isn't of expected type 'LinkedHashMap<int, bool>'.
+ - 'Map' is from 'dart:core'.
+ - 'LinkedHashMap' is from 'dart:collection'.
+Change the type of the map literal or the context in which it is used.
+  LinkedHashMap<int, bool> lhm = {};
+                                 ^" in <dynamic, dynamic>{};
+  core::Map<core::int*, core::bool*>* fm = await self::mapfun();
+  core::Set<core::int*>* fs = await self::setfun();
+  core::Iterable<core::int*>* fi = await self::iterablefun();
+  col::LinkedHashSet<core::int*>* flhs = await self::lhsfun();
+  col::LinkedHashMap<core::int*, core::bool*>* flhm = await self::lhmfun();
+  core::Map<core::int*, core::bool*>* fm2 = await self::mapfun2();
+  core::Set<core::int*>* fs2 = await self::setfun2();
+  core::Iterable<core::int*>* fi2 = await self::iterablefun2();
+  col::LinkedHashSet<core::int*>* flhs2 = await self::lhsfun2();
+  col::LinkedHashMap<core::int*, core::bool*>* flhm2 = await self::lhmfun2();
+}
+static method mapfun() → asy::Future<core::Map<core::int*, core::bool*>*>* async 
+  return <core::int*, core::bool*>{};
+static method setfun() → asy::Future<core::Set<core::int*>*>* async 
+  return block {
+    final core::Set<core::int*>* #t4 = col::LinkedHashSet::•<core::int*>();
+  } =>#t4;
+static method iterablefun() → asy::Future<core::Iterable<core::int*>*>* async 
+  return block {
+    final core::Set<core::int*>* #t5 = col::LinkedHashSet::•<core::int*>();
+  } =>#t5;
+static method lhsfun() → asy::Future<col::LinkedHashSet<core::int*>*>* async 
+  return invalid-expression "pkg/front_end/testcases/set_literals/disambiguation_rule.dart:32:46: Error: The set literal type 'Future<Set<dynamic>>' isn't of expected type 'Future<LinkedHashSet<int>>'.
+ - 'Future' is from 'dart:async'.
+ - 'Set' is from 'dart:core'.
+ - 'LinkedHashSet' is from 'dart:collection'.
+Change the type of the set literal or the context in which it is used.
+Future<LinkedHashSet<int>> lhsfun() async => {};
+                                             ^" in block {
+    final core::Set<dynamic>* #t6 = col::LinkedHashSet::•<dynamic>();
+  } =>#t6;
+static method lhmfun() → asy::Future<col::LinkedHashMap<core::int*, core::bool*>*>* async 
+  return invalid-expression "pkg/front_end/testcases/set_literals/disambiguation_rule.dart:33:52: Error: The map literal type 'Future<Map<dynamic, dynamic>>' isn't of expected type 'Future<LinkedHashMap<int, bool>>'.
+ - 'Future' is from 'dart:async'.
+ - 'Map' is from 'dart:core'.
+ - 'LinkedHashMap' is from 'dart:collection'.
+Change the type of the map literal or the context in which it is used.
+Future<LinkedHashMap<int, bool>> lhmfun() async => {};
+                                                   ^" in <dynamic, dynamic>{};
+static method mapfun2() → FutureOr<core::Map<core::int*, core::bool*>*>*
+  return <core::int*, core::bool*>{};
+static method setfun2() → FutureOr<core::Set<core::int*>*>*
+  return block {
+    final core::Set<core::int*>* #t7 = col::LinkedHashSet::•<core::int*>();
+  } =>#t7;
+static method iterablefun2() → FutureOr<core::Iterable<core::int*>*>*
+  return block {
+    final core::Set<core::int*>* #t8 = col::LinkedHashSet::•<core::int*>();
+  } =>#t8;
+static method lhsfun2() → FutureOr<col::LinkedHashSet<core::int*>*>*
+  return invalid-expression "pkg/front_end/testcases/set_literals/disambiguation_rule.dart:38:43: Error: A value of type 'Set<dynamic>' can't be assigned to a variable of type 'FutureOr<LinkedHashSet<int>>'.
+ - 'Set' is from 'dart:core'.
+ - 'LinkedHashSet' is from 'dart:collection'.
+FutureOr<LinkedHashSet<int>> lhsfun2() => {};
+                                          ^" in ( block {
+    final core::Set<dynamic>* #t9 = col::LinkedHashSet::•<dynamic>();
+  } =>#t9) as{TypeError} FutureOr<col::LinkedHashSet<core::int*>*>*;
+static method lhmfun2() → FutureOr<col::LinkedHashMap<core::int*, core::bool*>*>*
+  return invalid-expression "pkg/front_end/testcases/set_literals/disambiguation_rule.dart:39:49: Error: A value of type 'Map<dynamic, dynamic>' can't be assigned to a variable of type 'FutureOr<LinkedHashMap<int, bool>>'.
+ - 'Map' is from 'dart:core'.
+ - 'LinkedHashMap' is from 'dart:collection'.
+FutureOr<LinkedHashMap<int, bool>> lhmfun2() => {};
+                                                ^" in <dynamic, dynamic>{} as{TypeError} FutureOr<col::LinkedHashMap<core::int*, core::bool*>*>*;
diff --git a/pkg/front_end/testcases/static_field_lowering/enum.dart.weak.modular.expect b/pkg/front_end/testcases/static_field_lowering/enum.dart.weak.modular.expect
new file mode 100644
index 0000000..4d0ac34
--- /dev/null
+++ b/pkg/front_end/testcases/static_field_lowering/enum.dart.weak.modular.expect
@@ -0,0 +1,32 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::A> values = #C7;
+  static const field self::A a = #C3;
+  static const field self::A b = #C6;
+  const constructor •(core::int index, core::String name) → self::A
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String
+    return "A.${this.{core::_Enum::_name}{core::String}}";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+  #C2 = "a"
+  #C3 = self::A {index:#C1, _name:#C2}
+  #C4 = 1
+  #C5 = "b"
+  #C6 = self::A {index:#C4, _name:#C5}
+  #C7 = <self::A*>[#C3, #C6]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///enum.dart:
+- A. (from org-dartlang-testcase:///enum.dart:5:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:76:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
diff --git a/pkg/front_end/testcases/static_field_lowering/opt_in.dart.weak.modular.expect b/pkg/front_end/testcases/static_field_lowering/opt_in.dart.weak.modular.expect
new file mode 100644
index 0000000..bae037b
--- /dev/null
+++ b/pkg/front_end/testcases/static_field_lowering/opt_in.dart.weak.modular.expect
@@ -0,0 +1,340 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:_internal" as _in;
+
+class Class extends core::Object {
+  static const field core::int staticConstField = #C1;
+  static field core::int? staticFieldWithoutInitializer = null;
+  field core::int nonNullableInstanceFieldWithInitializer = self::init<core::int>(55);
+  field core::int? nullableInstanceFieldWithInitializer = self::init<core::int?>(17);
+  static field core::int? _#nonNullableStaticFieldWithInitializer1 = null;
+  static field core::bool _#nonNullableStaticFieldWithInitializer1#isSet = false;
+  static field core::int? _#nullableStaticFieldWithInitializer1 = null;
+  static field core::bool _#nullableStaticFieldWithInitializer1#isSet = false;
+  static field core::int? _#nonNullableStaticFieldWithInitializer2 = null;
+  static field core::bool _#nonNullableStaticFieldWithInitializer2#isSet = false;
+  static field core::int? _#nullableStaticFieldWithInitializer2 = null;
+  static field core::bool _#nullableStaticFieldWithInitializer2#isSet = false;
+  static field core::int? _#nonNullableStaticFinalFieldWithInitializer1 = null;
+  static field core::bool _#nonNullableStaticFinalFieldWithInitializer1#isSet = false;
+  static field core::int? _#nullableStaticFinalFieldWithInitializer1 = null;
+  static field core::bool _#nullableStaticFinalFieldWithInitializer1#isSet = false;
+  static field core::int? _#nonNullableStaticFinalFieldWithInitializer2Init = null;
+  static field core::bool _#nonNullableStaticFinalFieldWithInitializer2Init#isSet = false;
+  static field core::int? _#nonNullableStaticFinalFieldWithInitializer2 = null;
+  static field core::bool _#nonNullableStaticFinalFieldWithInitializer2#isSet = false;
+  static field core::int? _#nullableStaticFinalFieldWithInitializer2Init = null;
+  static field core::bool _#nullableStaticFinalFieldWithInitializer2Init#isSet = false;
+  static field core::int? _#nullableStaticFinalFieldWithInitializer2 = null;
+  static field core::bool _#nullableStaticFinalFieldWithInitializer2#isSet = false;
+  synthetic constructor •() → self::Class
+    : super core::Object::•()
+    ;
+  static get nonNullableStaticFieldWithInitializer1() → core::int {
+    if(!self::Class::_#nonNullableStaticFieldWithInitializer1#isSet) {
+      self::Class::_#nonNullableStaticFieldWithInitializer1 = self::init<core::int>(55);
+      self::Class::_#nonNullableStaticFieldWithInitializer1#isSet = true;
+    }
+    return let final core::int? #t1 = self::Class::_#nonNullableStaticFieldWithInitializer1 in #t1{core::int};
+  }
+  static set nonNullableStaticFieldWithInitializer1(core::int #t2) → void {
+    self::Class::_#nonNullableStaticFieldWithInitializer1#isSet = true;
+    self::Class::_#nonNullableStaticFieldWithInitializer1 = #t2;
+  }
+  static get nullableStaticFieldWithInitializer1() → core::int? {
+    if(!self::Class::_#nullableStaticFieldWithInitializer1#isSet) {
+      self::Class::_#nullableStaticFieldWithInitializer1 = self::init<core::int?>(17);
+      self::Class::_#nullableStaticFieldWithInitializer1#isSet = true;
+    }
+    return self::Class::_#nullableStaticFieldWithInitializer1;
+  }
+  static set nullableStaticFieldWithInitializer1(core::int? #t3) → void {
+    self::Class::_#nullableStaticFieldWithInitializer1#isSet = true;
+    self::Class::_#nullableStaticFieldWithInitializer1 = #t3;
+  }
+  static get nonNullableStaticFieldWithInitializer2() → core::int {
+    if(!self::Class::_#nonNullableStaticFieldWithInitializer2#isSet) {
+      self::Class::_#nonNullableStaticFieldWithInitializer2 = self::init<core::int>(55);
+      self::Class::_#nonNullableStaticFieldWithInitializer2#isSet = true;
+    }
+    return let final core::int? #t4 = self::Class::_#nonNullableStaticFieldWithInitializer2 in #t4{core::int};
+  }
+  static set nonNullableStaticFieldWithInitializer2(core::int #t5) → void {
+    self::Class::_#nonNullableStaticFieldWithInitializer2#isSet = true;
+    self::Class::_#nonNullableStaticFieldWithInitializer2 = #t5;
+  }
+  static get nullableStaticFieldWithInitializer2() → core::int? {
+    if(!self::Class::_#nullableStaticFieldWithInitializer2#isSet) {
+      self::Class::_#nullableStaticFieldWithInitializer2 = self::init<core::int?>(17);
+      self::Class::_#nullableStaticFieldWithInitializer2#isSet = true;
+    }
+    return self::Class::_#nullableStaticFieldWithInitializer2;
+  }
+  static set nullableStaticFieldWithInitializer2(core::int? #t6) → void {
+    self::Class::_#nullableStaticFieldWithInitializer2#isSet = true;
+    self::Class::_#nullableStaticFieldWithInitializer2 = #t6;
+  }
+  static get nonNullableStaticFinalFieldWithInitializer1() → core::int {
+    if(!self::Class::_#nonNullableStaticFinalFieldWithInitializer1#isSet) {
+      final core::int #t7 = self::init<core::int>(73);
+      if(self::Class::_#nonNullableStaticFinalFieldWithInitializer1#isSet)
+        throw new _in::LateError::fieldADI("nonNullableStaticFinalFieldWithInitializer1");
+      self::Class::_#nonNullableStaticFinalFieldWithInitializer1 = #t7;
+      self::Class::_#nonNullableStaticFinalFieldWithInitializer1#isSet = true;
+    }
+    return let final core::int? #t8 = self::Class::_#nonNullableStaticFinalFieldWithInitializer1 in #t8{core::int};
+  }
+  static get nullableStaticFinalFieldWithInitializer1() → core::int? {
+    if(!self::Class::_#nullableStaticFinalFieldWithInitializer1#isSet) {
+      final core::int? #t9 = self::init<core::int?>(19);
+      if(self::Class::_#nullableStaticFinalFieldWithInitializer1#isSet)
+        throw new _in::LateError::fieldADI("nullableStaticFinalFieldWithInitializer1");
+      self::Class::_#nullableStaticFinalFieldWithInitializer1 = #t9;
+      self::Class::_#nullableStaticFinalFieldWithInitializer1#isSet = true;
+    }
+    return self::Class::_#nullableStaticFinalFieldWithInitializer1;
+  }
+  static get nonNullableStaticFinalFieldWithInitializer2Init() → core::int {
+    if(!self::Class::_#nonNullableStaticFinalFieldWithInitializer2Init#isSet) {
+      self::Class::_#nonNullableStaticFinalFieldWithInitializer2Init = 0;
+      self::Class::_#nonNullableStaticFinalFieldWithInitializer2Init#isSet = true;
+    }
+    return let final core::int? #t10 = self::Class::_#nonNullableStaticFinalFieldWithInitializer2Init in #t10{core::int};
+  }
+  static set nonNullableStaticFinalFieldWithInitializer2Init(core::int #t11) → void {
+    self::Class::_#nonNullableStaticFinalFieldWithInitializer2Init#isSet = true;
+    self::Class::_#nonNullableStaticFinalFieldWithInitializer2Init = #t11;
+  }
+  static get nonNullableStaticFinalFieldWithInitializer2() → core::int {
+    if(!self::Class::_#nonNullableStaticFinalFieldWithInitializer2#isSet) {
+      final core::int #t12 = (let final core::int #t13 = self::Class::nonNullableStaticFinalFieldWithInitializer2Init in let final core::int #t14 = self::Class::nonNullableStaticFinalFieldWithInitializer2Init = #t13.{core::num::+}(1){(core::num) → core::int} in #t13) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int} self::Class::nonNullableStaticFinalFieldWithInitializer2.{core::num::+}(1){(core::num) → core::int} : 87;
+      if(self::Class::_#nonNullableStaticFinalFieldWithInitializer2#isSet)
+        throw new _in::LateError::fieldADI("nonNullableStaticFinalFieldWithInitializer2");
+      self::Class::_#nonNullableStaticFinalFieldWithInitializer2 = #t12;
+      self::Class::_#nonNullableStaticFinalFieldWithInitializer2#isSet = true;
+    }
+    return let final core::int? #t15 = self::Class::_#nonNullableStaticFinalFieldWithInitializer2 in #t15{core::int};
+  }
+  static get nullableStaticFinalFieldWithInitializer2Init() → core::int {
+    if(!self::Class::_#nullableStaticFinalFieldWithInitializer2Init#isSet) {
+      self::Class::_#nullableStaticFinalFieldWithInitializer2Init = 0;
+      self::Class::_#nullableStaticFinalFieldWithInitializer2Init#isSet = true;
+    }
+    return let final core::int? #t16 = self::Class::_#nullableStaticFinalFieldWithInitializer2Init in #t16{core::int};
+  }
+  static set nullableStaticFinalFieldWithInitializer2Init(core::int #t17) → void {
+    self::Class::_#nullableStaticFinalFieldWithInitializer2Init#isSet = true;
+    self::Class::_#nullableStaticFinalFieldWithInitializer2Init = #t17;
+  }
+  static get nullableStaticFinalFieldWithInitializer2() → core::int? {
+    if(!self::Class::_#nullableStaticFinalFieldWithInitializer2#isSet) {
+      final core::int? #t18 = (let final core::int #t19 = self::Class::nullableStaticFinalFieldWithInitializer2Init in let final core::int #t20 = self::Class::nullableStaticFinalFieldWithInitializer2Init = #t19.{core::num::+}(1){(core::num) → core::int} in #t19) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int} self::Class::nullableStaticFinalFieldWithInitializer2!.{core::num::+}(1){(core::num) → core::int} : 32;
+      if(self::Class::_#nullableStaticFinalFieldWithInitializer2#isSet)
+        throw new _in::LateError::fieldADI("nullableStaticFinalFieldWithInitializer2");
+      self::Class::_#nullableStaticFinalFieldWithInitializer2 = #t18;
+      self::Class::_#nullableStaticFinalFieldWithInitializer2#isSet = true;
+    }
+    return self::Class::_#nullableStaticFinalFieldWithInitializer2;
+  }
+}
+static field dynamic lastInit;
+static const field core::int constTopLevelField = #C2;
+static field core::int? topLevelFieldWithoutInitializer;
+static field core::int? _#nonNullableTopLevelFieldWithInitializer1 = null;
+static field core::bool _#nonNullableTopLevelFieldWithInitializer1#isSet = false;
+static field core::int? _#nullableTopLevelFieldWithInitializer = null;
+static field core::bool _#nullableTopLevelFieldWithInitializer#isSet = false;
+static field core::int? _#nonNullableTopLevelFieldWithInitializer2 = null;
+static field core::bool _#nonNullableTopLevelFieldWithInitializer2#isSet = false;
+static field core::int? _#nullableTopLevelFieldWithInitializer2 = null;
+static field core::bool _#nullableTopLevelFieldWithInitializer2#isSet = false;
+static field core::int? _#nonNullableFinalTopLevelFieldWithInitializer1 = null;
+static field core::bool _#nonNullableFinalTopLevelFieldWithInitializer1#isSet = false;
+static field core::int? _#nullableFinalTopLevelFieldWithInitializer1 = null;
+static field core::bool _#nullableFinalTopLevelFieldWithInitializer1#isSet = false;
+static field core::int? _#nonNullableFinalTopLevelFieldWithInitializer2Init = null;
+static field core::bool _#nonNullableFinalTopLevelFieldWithInitializer2Init#isSet = false;
+static field core::int? _#nonNullableFinalTopLevelFieldWithInitializer2 = null;
+static field core::bool _#nonNullableFinalTopLevelFieldWithInitializer2#isSet = false;
+static field core::int? _#nullableFinalTopLevelFieldWithInitializer2Init = null;
+static field core::bool _#nullableFinalTopLevelFieldWithInitializer2Init#isSet = false;
+static field core::int? _#nullableFinalTopLevelFieldWithInitializer2 = null;
+static field core::bool _#nullableFinalTopLevelFieldWithInitializer2#isSet = false;
+static method init<T extends core::Object? = dynamic>(self::init::T% value) → self::init::T% {
+  self::lastInit = value;
+  return value;
+}
+static get nonNullableTopLevelFieldWithInitializer1() → core::int {
+  if(!self::_#nonNullableTopLevelFieldWithInitializer1#isSet) {
+    self::_#nonNullableTopLevelFieldWithInitializer1 = self::init<core::int>(42);
+    self::_#nonNullableTopLevelFieldWithInitializer1#isSet = true;
+  }
+  return let final core::int? #t21 = self::_#nonNullableTopLevelFieldWithInitializer1 in #t21{core::int};
+}
+static set nonNullableTopLevelFieldWithInitializer1(core::int #t22) → void {
+  self::_#nonNullableTopLevelFieldWithInitializer1#isSet = true;
+  self::_#nonNullableTopLevelFieldWithInitializer1 = #t22;
+}
+static get nullableTopLevelFieldWithInitializer() → core::int? {
+  if(!self::_#nullableTopLevelFieldWithInitializer#isSet) {
+    self::_#nullableTopLevelFieldWithInitializer = self::init<core::int?>(123);
+    self::_#nullableTopLevelFieldWithInitializer#isSet = true;
+  }
+  return self::_#nullableTopLevelFieldWithInitializer;
+}
+static set nullableTopLevelFieldWithInitializer(core::int? #t23) → void {
+  self::_#nullableTopLevelFieldWithInitializer#isSet = true;
+  self::_#nullableTopLevelFieldWithInitializer = #t23;
+}
+static get nonNullableTopLevelFieldWithInitializer2() → core::int {
+  if(!self::_#nonNullableTopLevelFieldWithInitializer2#isSet) {
+    self::_#nonNullableTopLevelFieldWithInitializer2 = self::init<core::int>(42);
+    self::_#nonNullableTopLevelFieldWithInitializer2#isSet = true;
+  }
+  return let final core::int? #t24 = self::_#nonNullableTopLevelFieldWithInitializer2 in #t24{core::int};
+}
+static set nonNullableTopLevelFieldWithInitializer2(core::int #t25) → void {
+  self::_#nonNullableTopLevelFieldWithInitializer2#isSet = true;
+  self::_#nonNullableTopLevelFieldWithInitializer2 = #t25;
+}
+static get nullableTopLevelFieldWithInitializer2() → core::int? {
+  if(!self::_#nullableTopLevelFieldWithInitializer2#isSet) {
+    self::_#nullableTopLevelFieldWithInitializer2 = self::init<core::int?>(123);
+    self::_#nullableTopLevelFieldWithInitializer2#isSet = true;
+  }
+  return self::_#nullableTopLevelFieldWithInitializer2;
+}
+static set nullableTopLevelFieldWithInitializer2(core::int? #t26) → void {
+  self::_#nullableTopLevelFieldWithInitializer2#isSet = true;
+  self::_#nullableTopLevelFieldWithInitializer2 = #t26;
+}
+static get nonNullableFinalTopLevelFieldWithInitializer1() → core::int {
+  if(!self::_#nonNullableFinalTopLevelFieldWithInitializer1#isSet) {
+    final core::int #t27 = self::init<core::int>(87);
+    if(self::_#nonNullableFinalTopLevelFieldWithInitializer1#isSet)
+      throw new _in::LateError::fieldADI("nonNullableFinalTopLevelFieldWithInitializer1");
+    self::_#nonNullableFinalTopLevelFieldWithInitializer1 = #t27;
+    self::_#nonNullableFinalTopLevelFieldWithInitializer1#isSet = true;
+  }
+  return let final core::int? #t28 = self::_#nonNullableFinalTopLevelFieldWithInitializer1 in #t28{core::int};
+}
+static get nullableFinalTopLevelFieldWithInitializer1() → core::int? {
+  if(!self::_#nullableFinalTopLevelFieldWithInitializer1#isSet) {
+    final core::int? #t29 = self::init<core::int?>(32);
+    if(self::_#nullableFinalTopLevelFieldWithInitializer1#isSet)
+      throw new _in::LateError::fieldADI("nullableFinalTopLevelFieldWithInitializer1");
+    self::_#nullableFinalTopLevelFieldWithInitializer1 = #t29;
+    self::_#nullableFinalTopLevelFieldWithInitializer1#isSet = true;
+  }
+  return self::_#nullableFinalTopLevelFieldWithInitializer1;
+}
+static get nonNullableFinalTopLevelFieldWithInitializer2Init() → core::int {
+  if(!self::_#nonNullableFinalTopLevelFieldWithInitializer2Init#isSet) {
+    self::_#nonNullableFinalTopLevelFieldWithInitializer2Init = 0;
+    self::_#nonNullableFinalTopLevelFieldWithInitializer2Init#isSet = true;
+  }
+  return let final core::int? #t30 = self::_#nonNullableFinalTopLevelFieldWithInitializer2Init in #t30{core::int};
+}
+static set nonNullableFinalTopLevelFieldWithInitializer2Init(core::int #t31) → void {
+  self::_#nonNullableFinalTopLevelFieldWithInitializer2Init#isSet = true;
+  self::_#nonNullableFinalTopLevelFieldWithInitializer2Init = #t31;
+}
+static get nonNullableFinalTopLevelFieldWithInitializer2() → core::int {
+  if(!self::_#nonNullableFinalTopLevelFieldWithInitializer2#isSet) {
+    final core::int #t32 = (let final core::int #t33 = self::nonNullableFinalTopLevelFieldWithInitializer2Init in let final core::int #t34 = self::nonNullableFinalTopLevelFieldWithInitializer2Init = #t33.{core::num::+}(1){(core::num) → core::int} in #t33) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int} self::nonNullableFinalTopLevelFieldWithInitializer2.{core::num::+}(1){(core::num) → core::int} : 87;
+    if(self::_#nonNullableFinalTopLevelFieldWithInitializer2#isSet)
+      throw new _in::LateError::fieldADI("nonNullableFinalTopLevelFieldWithInitializer2");
+    self::_#nonNullableFinalTopLevelFieldWithInitializer2 = #t32;
+    self::_#nonNullableFinalTopLevelFieldWithInitializer2#isSet = true;
+  }
+  return let final core::int? #t35 = self::_#nonNullableFinalTopLevelFieldWithInitializer2 in #t35{core::int};
+}
+static get nullableFinalTopLevelFieldWithInitializer2Init() → core::int {
+  if(!self::_#nullableFinalTopLevelFieldWithInitializer2Init#isSet) {
+    self::_#nullableFinalTopLevelFieldWithInitializer2Init = 0;
+    self::_#nullableFinalTopLevelFieldWithInitializer2Init#isSet = true;
+  }
+  return let final core::int? #t36 = self::_#nullableFinalTopLevelFieldWithInitializer2Init in #t36{core::int};
+}
+static set nullableFinalTopLevelFieldWithInitializer2Init(core::int #t37) → void {
+  self::_#nullableFinalTopLevelFieldWithInitializer2Init#isSet = true;
+  self::_#nullableFinalTopLevelFieldWithInitializer2Init = #t37;
+}
+static get nullableFinalTopLevelFieldWithInitializer2() → core::int? {
+  if(!self::_#nullableFinalTopLevelFieldWithInitializer2#isSet) {
+    final core::int? #t38 = (let final core::int #t39 = self::nullableFinalTopLevelFieldWithInitializer2Init in let final core::int #t40 = self::nullableFinalTopLevelFieldWithInitializer2Init = #t39.{core::num::+}(1){(core::num) → core::int} in #t39) =={core::num::==}{(core::Object) → core::bool} 0 ?{core::int} self::nullableFinalTopLevelFieldWithInitializer2!.{core::num::+}(1){(core::num) → core::int} : 32;
+    if(self::_#nullableFinalTopLevelFieldWithInitializer2#isSet)
+      throw new _in::LateError::fieldADI("nullableFinalTopLevelFieldWithInitializer2");
+    self::_#nullableFinalTopLevelFieldWithInitializer2 = #t38;
+    self::_#nullableFinalTopLevelFieldWithInitializer2#isSet = true;
+  }
+  return self::_#nullableFinalTopLevelFieldWithInitializer2;
+}
+static method main() → dynamic {
+  self::expect(null, self::lastInit);
+  self::expect(null, self::topLevelFieldWithoutInitializer);
+  self::expect(324, #C2);
+  self::expect(null, self::Class::staticFieldWithoutInitializer);
+  self::expect(123, #C1);
+  self::expect(42, self::nonNullableTopLevelFieldWithInitializer1);
+  self::expect(42, self::lastInit);
+  self::expect(123, self::nullableTopLevelFieldWithInitializer);
+  self::expect(123, self::lastInit);
+  self::nonNullableTopLevelFieldWithInitializer2 = 56;
+  self::expect(123, self::lastInit);
+  self::expect(56, self::nonNullableTopLevelFieldWithInitializer2);
+  self::expect(123, self::lastInit);
+  self::nullableTopLevelFieldWithInitializer2 = 7;
+  self::expect(123, self::lastInit);
+  self::expect(7, self::nullableTopLevelFieldWithInitializer2);
+  self::expect(123, self::lastInit);
+  self::expect(87, self::nonNullableFinalTopLevelFieldWithInitializer1);
+  self::expect(87, self::lastInit);
+  self::expect(32, self::nullableFinalTopLevelFieldWithInitializer1);
+  self::expect(32, self::lastInit);
+  self::throws(() → core::int => self::nonNullableFinalTopLevelFieldWithInitializer2, "Read nonNullableFinalTopLevelFieldWithInitializer2");
+  self::throws(() → core::int? => self::nullableFinalTopLevelFieldWithInitializer2, "Read nullableFinalTopLevelFieldWithInitializer2");
+  self::expect(55, self::Class::nonNullableStaticFieldWithInitializer1);
+  self::expect(55, self::lastInit);
+  self::expect(17, self::Class::nullableStaticFieldWithInitializer1);
+  self::expect(17, self::lastInit);
+  self::Class::nonNullableStaticFieldWithInitializer2 = 63;
+  self::expect(17, self::lastInit);
+  self::expect(63, self::Class::nonNullableStaticFieldWithInitializer2);
+  self::expect(17, self::lastInit);
+  self::Class::nullableStaticFieldWithInitializer2 = 89;
+  self::expect(17, self::lastInit);
+  self::expect(89, self::Class::nullableStaticFieldWithInitializer2);
+  self::expect(17, self::lastInit);
+  self::expect(73, self::Class::nonNullableStaticFinalFieldWithInitializer1);
+  self::expect(73, self::lastInit);
+  self::expect(19, self::Class::nullableStaticFinalFieldWithInitializer1);
+  self::expect(19, self::lastInit);
+  self::throws(() → core::int => self::Class::nonNullableStaticFinalFieldWithInitializer2, "Read nonNullableStaticFinalFieldWithInitializer2");
+  self::throws(() → core::int? => self::Class::nullableStaticFinalFieldWithInitializer2, "Read nullableStaticFinalFieldWithInitializer2");
+  self::Class c = new self::Class::•();
+  self::expect(17, self::lastInit);
+  self::expect(55, c.{self::Class::nonNullableInstanceFieldWithInitializer}{core::int});
+  self::expect(17, c.{self::Class::nullableInstanceFieldWithInitializer}{core::int?});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() → dynamic f, core::String message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() → dynamic};
+  }
+  on core::Error catch(final core::Error e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
+
+constants  {
+  #C1 = 123
+  #C2 = 324
+}
diff --git a/pkg/front_end/testcases/static_field_lowering/opt_out.dart.weak.modular.expect b/pkg/front_end/testcases/static_field_lowering/opt_out.dart.weak.modular.expect
new file mode 100644
index 0000000..be71725
--- /dev/null
+++ b/pkg/front_end/testcases/static_field_lowering/opt_out.dart.weak.modular.expect
@@ -0,0 +1,87 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class Class extends core::Object {
+  static const field core::int* staticConstField = #C1;
+  field core::int* instanceFieldWithInitializer = self::init<core::int*>(55);
+  static field core::int* staticFieldWithoutInitializer = null;
+  static field core::int* staticFieldWithInitializer1 = self::init<core::int*>(55);
+  static field core::int* staticFieldWithInitializer2 = self::init<core::int*>(55);
+  static final field core::int* staticFinalFieldWithInitializer1 = self::init<core::int*>(73);
+  static field core::int* staticFinalFieldWithInitializer2Init = 0;
+  static final field core::int* staticFinalFieldWithInitializer2 = (let final core::int* #t1 = self::Class::staticFinalFieldWithInitializer2Init in let final core::int* #t2 = self::Class::staticFinalFieldWithInitializer2Init = #t1.{core::num::+}(1){(core::num*) →* core::int*} in #t1) =={core::num::==}{(core::Object*) →* core::bool*} 0 ?{core::int*} self::Class::staticFinalFieldWithInitializer2.{core::num::+}(1){(core::num*) →* core::int*} : 87;
+  synthetic constructor •() → self::Class*
+    : super core::Object::•()
+    ;
+  abstract member-signature get _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature operator ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method toString() → core::String*; -> core::Object::toString
+  abstract member-signature method noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get runtimeType() → core::Type*; -> core::Object::runtimeType
+}
+static field dynamic lastInit;
+static const field core::int* constTopLevelField = #C2;
+static field core::int* topLevelFieldWithoutInitializer;
+static field core::int* topLevelFieldWithInitializer1 = self::init<core::int*>(42);
+static field core::int* topLevelFieldWithInitializer2 = self::init<core::int*>(42);
+static final field core::int* finalTopLevelFieldWithInitializer1 = self::init<core::int*>(87);
+static field core::int* finalTopLevelFieldWithInitializer2Init = 0;
+static final field core::int* finalTopLevelFieldWithInitializer2 = (let final core::int* #t3 = self::finalTopLevelFieldWithInitializer2Init in let final core::int* #t4 = self::finalTopLevelFieldWithInitializer2Init = #t3.{core::num::+}(1){(core::num*) →* core::int*} in #t3) =={core::num::==}{(core::Object*) →* core::bool*} 0 ?{core::int*} self::finalTopLevelFieldWithInitializer2.{core::num::+}(1){(core::num*) →* core::int*} : 87;
+static method init<T extends core::Object* = dynamic>(self::init::T* value) → self::init::T* {
+  self::lastInit = value;
+  return value;
+}
+static method main() → dynamic {
+  self::expect(null, self::lastInit);
+  self::expect(null, self::topLevelFieldWithoutInitializer);
+  self::expect(324, #C2);
+  self::expect(null, self::Class::staticFieldWithoutInitializer);
+  self::expect(123, #C1);
+  self::expect(42, self::topLevelFieldWithInitializer1);
+  self::expect(42, self::lastInit);
+  self::topLevelFieldWithInitializer2 = 56;
+  self::expect(42, self::lastInit);
+  self::expect(56, self::topLevelFieldWithInitializer2);
+  self::expect(42, self::lastInit);
+  self::expect(87, self::finalTopLevelFieldWithInitializer1);
+  self::expect(87, self::lastInit);
+  self::throws(() → core::int* => self::finalTopLevelFieldWithInitializer2, "Read finalTopLevelFieldWithInitializer2");
+  self::expect(55, self::Class::staticFieldWithInitializer1);
+  self::expect(55, self::lastInit);
+  self::Class::staticFieldWithInitializer2 = 63;
+  self::expect(55, self::lastInit);
+  self::expect(63, self::Class::staticFieldWithInitializer2);
+  self::expect(55, self::lastInit);
+  self::expect(73, self::Class::staticFinalFieldWithInitializer1);
+  self::expect(73, self::lastInit);
+  self::throws(() → core::int* => self::Class::staticFinalFieldWithInitializer2, "Read staticFinalFieldWithInitializer2");
+  self::Class* c = new self::Class::•();
+  self::expect(55, self::lastInit);
+  self::expect(55, c.{self::Class::instanceFieldWithInitializer}{core::int*});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object*) →* core::bool*} actual))
+    throw "Expected ${expected}, actual ${actual}";
+}
+static method throws(() →* dynamic f, core::String* message) → dynamic {
+  dynamic value;
+  try {
+    value = f(){() →* dynamic};
+  }
+  on dynamic catch(final dynamic e) {
+    core::print(e);
+    return;
+  }
+  throw "${message}: ${value}";
+}
+
+constants  {
+  #C1 = 123
+  #C2 = 324
+}
diff --git a/pkg/front_end/testcases/strong.status b/pkg/front_end/testcases/strong.status
index e35f2a1..2aef19d 100644
--- a/pkg/front_end/testcases/strong.status
+++ b/pkg/front_end/testcases/strong.status
@@ -6,6 +6,8 @@
 # Kernel ASTs directly, that is, code in pkg/fasta/lib/src/kernel/ with
 # strong-mode enabled.
 
+dart2js/flutter_issue94561/main: SemiFuzzFailure
+dart2js/flutter_issue94561/main.no_link: SemiFuzzFailure
 dart2js/late_fields: SemiFuzzFailure
 dart2js/late_from_dill/main: SemiFuzzFailure
 dart2js/late_statics: SemiFuzzFailure
diff --git a/pkg/front_end/testcases/super_parameters/simple.dart.strong.expect b/pkg/front_end/testcases/super_parameters/simple.dart.strong.expect
index a1ba70a..2738e5e 100644
--- a/pkg/front_end/testcases/super_parameters/simple.dart.strong.expect
+++ b/pkg/front_end/testcases/super_parameters/simple.dart.strong.expect
@@ -1,11 +1,4 @@
 library /*isNonNullableByDefault*/;
-//
-// Problems in library:
-//
-// pkg/front_end/testcases/super_parameters/simple.dart:11:3: Error: The superclass, 'A', has no unnamed constructor that takes no arguments.
-//   B(super.foo);
-//   ^
-//
 import self as self;
 import "dart:core" as core;
 
@@ -17,9 +10,7 @@
 }
 class B extends self::A {
   constructor •(dynamic foo) → self::B
-    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/super_parameters/simple.dart:11:3: Error: The superclass, 'A', has no unnamed constructor that takes no arguments.
-  B(super.foo);
-  ^"
+    : super self::A::•(foo)
     ;
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/super_parameters/simple.dart.strong.transformed.expect b/pkg/front_end/testcases/super_parameters/simple.dart.strong.transformed.expect
index a1ba70a..2738e5e 100644
--- a/pkg/front_end/testcases/super_parameters/simple.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/super_parameters/simple.dart.strong.transformed.expect
@@ -1,11 +1,4 @@
 library /*isNonNullableByDefault*/;
-//
-// Problems in library:
-//
-// pkg/front_end/testcases/super_parameters/simple.dart:11:3: Error: The superclass, 'A', has no unnamed constructor that takes no arguments.
-//   B(super.foo);
-//   ^
-//
 import self as self;
 import "dart:core" as core;
 
@@ -17,9 +10,7 @@
 }
 class B extends self::A {
   constructor •(dynamic foo) → self::B
-    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/super_parameters/simple.dart:11:3: Error: The superclass, 'A', has no unnamed constructor that takes no arguments.
-  B(super.foo);
-  ^"
+    : super self::A::•(foo)
     ;
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/super_parameters/simple.dart.weak.expect b/pkg/front_end/testcases/super_parameters/simple.dart.weak.expect
index a1ba70a..2738e5e 100644
--- a/pkg/front_end/testcases/super_parameters/simple.dart.weak.expect
+++ b/pkg/front_end/testcases/super_parameters/simple.dart.weak.expect
@@ -1,11 +1,4 @@
 library /*isNonNullableByDefault*/;
-//
-// Problems in library:
-//
-// pkg/front_end/testcases/super_parameters/simple.dart:11:3: Error: The superclass, 'A', has no unnamed constructor that takes no arguments.
-//   B(super.foo);
-//   ^
-//
 import self as self;
 import "dart:core" as core;
 
@@ -17,9 +10,7 @@
 }
 class B extends self::A {
   constructor •(dynamic foo) → self::B
-    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/super_parameters/simple.dart:11:3: Error: The superclass, 'A', has no unnamed constructor that takes no arguments.
-  B(super.foo);
-  ^"
+    : super self::A::•(foo)
     ;
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/super_parameters/simple.dart.weak.modular.expect b/pkg/front_end/testcases/super_parameters/simple.dart.weak.modular.expect
new file mode 100644
index 0000000..2738e5e
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple.dart.weak.modular.expect
@@ -0,0 +1,16 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  final field core::int foo;
+  constructor •(core::int foo) → self::A
+    : self::A::foo = foo, super core::Object::•()
+    ;
+}
+class B extends self::A {
+  constructor •(dynamic foo) → self::B
+    : super self::A::•(foo)
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/super_parameters/simple.dart.weak.transformed.expect b/pkg/front_end/testcases/super_parameters/simple.dart.weak.transformed.expect
index a1ba70a..2738e5e 100644
--- a/pkg/front_end/testcases/super_parameters/simple.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/super_parameters/simple.dart.weak.transformed.expect
@@ -1,11 +1,4 @@
 library /*isNonNullableByDefault*/;
-//
-// Problems in library:
-//
-// pkg/front_end/testcases/super_parameters/simple.dart:11:3: Error: The superclass, 'A', has no unnamed constructor that takes no arguments.
-//   B(super.foo);
-//   ^
-//
 import self as self;
 import "dart:core" as core;
 
@@ -17,9 +10,7 @@
 }
 class B extends self::A {
   constructor •(dynamic foo) → self::B
-    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/super_parameters/simple.dart:11:3: Error: The superclass, 'A', has no unnamed constructor that takes no arguments.
-  B(super.foo);
-  ^"
+    : super self::A::•(foo)
     ;
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart
new file mode 100644
index 0000000..bd5cc28
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart
@@ -0,0 +1,33 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+class A1 {
+  final int foo;
+  A1({required this.foo});
+}
+
+class B1 extends A1 {
+  B1({required super.foo}) : super(); // Ok.
+}
+
+class C1 extends A1 {
+  C1({required super.foo}) : super(foo: foo); // Error.
+}
+
+class A2 {
+  final int foo;
+  final String bar;
+  A2({required this.foo, required this.bar});
+}
+
+class B2 extends A2 {
+  B2() : super(foo: 42, bar: "bar", baz: false); // Error.
+}
+
+class C2 extends A2 {
+  C2({required super.foo}) : super(); // Error.
+  C2.other({required super.foo}) : super(bar: 'bar'); // Ok.
+}
+
+main() {}
diff --git a/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.strong.expect b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.strong.expect
new file mode 100644
index 0000000..01051cd
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.strong.expect
@@ -0,0 +1,68 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:15:22: Error: Duplicated named argument 'foo'.
+//   C1({required super.foo}) : super(foo: foo); // Error.
+//                      ^^^
+//
+// pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:25:37: Error: No named parameter with the name 'baz'.
+//   B2() : super(foo: 42, bar: "bar", baz: false); // Error.
+//                                     ^^^
+//
+// pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:29:35: Error: Required named parameter 'bar' must be provided.
+//   C2({required super.foo}) : super(); // Error.
+//                                   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  final field core::int foo;
+  constructor •({required core::int foo = #C1}) → self::A1
+    : self::A1::foo = foo, super core::Object::•()
+    ;
+}
+class B1 extends self::A1 {
+  constructor •({required dynamic foo = #C1}) → self::B1
+    : super self::A1::•(foo: foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+class C1 extends self::A1 {
+  constructor •({required dynamic foo = #C1}) → self::C1
+    : super self::A1::•(foo: invalid-expression "pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:15:22: Error: Duplicated named argument 'foo'.
+  C1({required super.foo}) : super(foo: foo); // Error.
+                     ^^^" in block {
+      foo;
+    } =>foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+class A2 extends core::Object {
+  final field core::int foo;
+  final field core::String bar;
+  constructor •({required core::int foo = #C1, required core::String bar = #C1}) → self::A2
+    : self::A2::foo = foo, self::A2::bar = bar, super core::Object::•()
+    ;
+}
+class B2 extends self::A2 {
+  constructor •() → self::B2
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:25:37: Error: No named parameter with the name 'baz'.
+  B2() : super(foo: 42, bar: \"bar\", baz: false); // Error.
+                                    ^^^"
+    ;
+}
+class C2 extends self::A2 {
+  constructor •({required dynamic foo = #C1}) → self::C2
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:29:35: Error: Required named parameter 'bar' must be provided.
+  C2({required super.foo}) : super(); // Error.
+                                  ^"
+    ;
+  constructor other({required dynamic foo = #C1}) → self::C2
+    : super self::A2::•(bar: "bar", foo: foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.strong.transformed.expect b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.strong.transformed.expect
new file mode 100644
index 0000000..74cac10
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.strong.transformed.expect
@@ -0,0 +1,68 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:15:22: Error: Duplicated named argument 'foo'.
+//   C1({required super.foo}) : super(foo: foo); // Error.
+//                      ^^^
+//
+// pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:25:37: Error: No named parameter with the name 'baz'.
+//   B2() : super(foo: 42, bar: "bar", baz: false); // Error.
+//                                     ^^^
+//
+// pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:29:35: Error: Required named parameter 'bar' must be provided.
+//   C2({required super.foo}) : super(); // Error.
+//                                   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  final field core::int foo;
+  constructor •({required core::int foo = #C1}) → self::A1
+    : self::A1::foo = foo, super core::Object::•()
+    ;
+}
+class B1 extends self::A1 {
+  constructor •({required dynamic foo = #C1}) → self::B1
+    : super self::A1::•(foo: foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+class C1 extends self::A1 {
+  constructor •({required dynamic foo = #C1}) → self::C1
+    : super self::A1::•(foo: invalid-expression "pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:15:22: Error: Duplicated named argument 'foo'.
+  C1({required super.foo}) : super(foo: foo); // Error.
+                     ^^^" in block {
+      foo;
+    } =>foo)
+    ;
+}
+class A2 extends core::Object {
+  final field core::int foo;
+  final field core::String bar;
+  constructor •({required core::int foo = #C1, required core::String bar = #C1}) → self::A2
+    : self::A2::foo = foo, self::A2::bar = bar, super core::Object::•()
+    ;
+}
+class B2 extends self::A2 {
+  constructor •() → self::B2
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:25:37: Error: No named parameter with the name 'baz'.
+  B2() : super(foo: 42, bar: \"bar\", baz: false); // Error.
+                                    ^^^"
+    ;
+}
+class C2 extends self::A2 {
+  constructor •({required dynamic foo = #C1}) → self::C2
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:29:35: Error: Required named parameter 'bar' must be provided.
+  C2({required super.foo}) : super(); // Error.
+                                  ^"
+    ;
+  constructor other({required dynamic foo = #C1}) → self::C2
+    : super self::A2::•(bar: "bar", foo: foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.textual_outline.expect b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.textual_outline.expect
new file mode 100644
index 0000000..3c4243b
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.textual_outline.expect
@@ -0,0 +1,23 @@
+class A1 {
+  final int foo;
+  A1({required this.foo});
+}
+class B1 extends A1 {
+  B1({required super.foo}) : super();
+}
+class C1 extends A1 {
+  C1({required super.foo}) : super(foo: foo);
+}
+class A2 {
+  final int foo;
+  final String bar;
+  A2({required this.foo, required this.bar});
+}
+class B2 extends A2 {
+  B2() : super(foo: 42, bar: "bar", baz: false);
+}
+class C2 extends A2 {
+  C2({required super.foo}) : super();
+  C2.other({required super.foo}) : super(bar: 'bar');
+}
+main() {}
diff --git a/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.weak.expect b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.weak.expect
new file mode 100644
index 0000000..01051cd
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.weak.expect
@@ -0,0 +1,68 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:15:22: Error: Duplicated named argument 'foo'.
+//   C1({required super.foo}) : super(foo: foo); // Error.
+//                      ^^^
+//
+// pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:25:37: Error: No named parameter with the name 'baz'.
+//   B2() : super(foo: 42, bar: "bar", baz: false); // Error.
+//                                     ^^^
+//
+// pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:29:35: Error: Required named parameter 'bar' must be provided.
+//   C2({required super.foo}) : super(); // Error.
+//                                   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  final field core::int foo;
+  constructor •({required core::int foo = #C1}) → self::A1
+    : self::A1::foo = foo, super core::Object::•()
+    ;
+}
+class B1 extends self::A1 {
+  constructor •({required dynamic foo = #C1}) → self::B1
+    : super self::A1::•(foo: foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+class C1 extends self::A1 {
+  constructor •({required dynamic foo = #C1}) → self::C1
+    : super self::A1::•(foo: invalid-expression "pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:15:22: Error: Duplicated named argument 'foo'.
+  C1({required super.foo}) : super(foo: foo); // Error.
+                     ^^^" in block {
+      foo;
+    } =>foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+class A2 extends core::Object {
+  final field core::int foo;
+  final field core::String bar;
+  constructor •({required core::int foo = #C1, required core::String bar = #C1}) → self::A2
+    : self::A2::foo = foo, self::A2::bar = bar, super core::Object::•()
+    ;
+}
+class B2 extends self::A2 {
+  constructor •() → self::B2
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:25:37: Error: No named parameter with the name 'baz'.
+  B2() : super(foo: 42, bar: \"bar\", baz: false); // Error.
+                                    ^^^"
+    ;
+}
+class C2 extends self::A2 {
+  constructor •({required dynamic foo = #C1}) → self::C2
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:29:35: Error: Required named parameter 'bar' must be provided.
+  C2({required super.foo}) : super(); // Error.
+                                  ^"
+    ;
+  constructor other({required dynamic foo = #C1}) → self::C2
+    : super self::A2::•(bar: "bar", foo: foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.weak.modular.expect b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.weak.modular.expect
new file mode 100644
index 0000000..01051cd
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.weak.modular.expect
@@ -0,0 +1,68 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:15:22: Error: Duplicated named argument 'foo'.
+//   C1({required super.foo}) : super(foo: foo); // Error.
+//                      ^^^
+//
+// pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:25:37: Error: No named parameter with the name 'baz'.
+//   B2() : super(foo: 42, bar: "bar", baz: false); // Error.
+//                                     ^^^
+//
+// pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:29:35: Error: Required named parameter 'bar' must be provided.
+//   C2({required super.foo}) : super(); // Error.
+//                                   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  final field core::int foo;
+  constructor •({required core::int foo = #C1}) → self::A1
+    : self::A1::foo = foo, super core::Object::•()
+    ;
+}
+class B1 extends self::A1 {
+  constructor •({required dynamic foo = #C1}) → self::B1
+    : super self::A1::•(foo: foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+class C1 extends self::A1 {
+  constructor •({required dynamic foo = #C1}) → self::C1
+    : super self::A1::•(foo: invalid-expression "pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:15:22: Error: Duplicated named argument 'foo'.
+  C1({required super.foo}) : super(foo: foo); // Error.
+                     ^^^" in block {
+      foo;
+    } =>foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+class A2 extends core::Object {
+  final field core::int foo;
+  final field core::String bar;
+  constructor •({required core::int foo = #C1, required core::String bar = #C1}) → self::A2
+    : self::A2::foo = foo, self::A2::bar = bar, super core::Object::•()
+    ;
+}
+class B2 extends self::A2 {
+  constructor •() → self::B2
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:25:37: Error: No named parameter with the name 'baz'.
+  B2() : super(foo: 42, bar: \"bar\", baz: false); // Error.
+                                    ^^^"
+    ;
+}
+class C2 extends self::A2 {
+  constructor •({required dynamic foo = #C1}) → self::C2
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:29:35: Error: Required named parameter 'bar' must be provided.
+  C2({required super.foo}) : super(); // Error.
+                                  ^"
+    ;
+  constructor other({required dynamic foo = #C1}) → self::C2
+    : super self::A2::•(bar: "bar", foo: foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.weak.outline.expect b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.weak.outline.expect
new file mode 100644
index 0000000..f3d5bdd
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.weak.outline.expect
@@ -0,0 +1,35 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  final field core::int foo;
+  constructor •({required core::int foo}) → self::A1
+    ;
+}
+class B1 extends self::A1 {
+  constructor •({required dynamic foo}) → self::B1
+    ;
+}
+class C1 extends self::A1 {
+  constructor •({required dynamic foo}) → self::C1
+    ;
+}
+class A2 extends core::Object {
+  final field core::int foo;
+  final field core::String bar;
+  constructor •({required core::int foo, required core::String bar}) → self::A2
+    ;
+}
+class B2 extends self::A2 {
+  constructor •() → self::B2
+    ;
+}
+class C2 extends self::A2 {
+  constructor •({required dynamic foo}) → self::C2
+    ;
+  constructor other({required dynamic foo}) → self::C2
+    ;
+}
+static method main() → dynamic
+  ;
diff --git a/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.weak.transformed.expect b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.weak.transformed.expect
new file mode 100644
index 0000000..74cac10
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart.weak.transformed.expect
@@ -0,0 +1,68 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:15:22: Error: Duplicated named argument 'foo'.
+//   C1({required super.foo}) : super(foo: foo); // Error.
+//                      ^^^
+//
+// pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:25:37: Error: No named parameter with the name 'baz'.
+//   B2() : super(foo: 42, bar: "bar", baz: false); // Error.
+//                                     ^^^
+//
+// pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:29:35: Error: Required named parameter 'bar' must be provided.
+//   C2({required super.foo}) : super(); // Error.
+//                                   ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  final field core::int foo;
+  constructor •({required core::int foo = #C1}) → self::A1
+    : self::A1::foo = foo, super core::Object::•()
+    ;
+}
+class B1 extends self::A1 {
+  constructor •({required dynamic foo = #C1}) → self::B1
+    : super self::A1::•(foo: foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+class C1 extends self::A1 {
+  constructor •({required dynamic foo = #C1}) → self::C1
+    : super self::A1::•(foo: invalid-expression "pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:15:22: Error: Duplicated named argument 'foo'.
+  C1({required super.foo}) : super(foo: foo); // Error.
+                     ^^^" in block {
+      foo;
+    } =>foo)
+    ;
+}
+class A2 extends core::Object {
+  final field core::int foo;
+  final field core::String bar;
+  constructor •({required core::int foo = #C1, required core::String bar = #C1}) → self::A2
+    : self::A2::foo = foo, self::A2::bar = bar, super core::Object::•()
+    ;
+}
+class B2 extends self::A2 {
+  constructor •() → self::B2
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:25:37: Error: No named parameter with the name 'baz'.
+  B2() : super(foo: 42, bar: \"bar\", baz: false); // Error.
+                                    ^^^"
+    ;
+}
+class C2 extends self::A2 {
+  constructor •({required dynamic foo = #C1}) → self::C2
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_named_super_parameters.dart:29:35: Error: Required named parameter 'bar' must be provided.
+  C2({required super.foo}) : super(); // Error.
+                                  ^"
+    ;
+  constructor other({required dynamic foo = #C1}) → self::C2
+    : super self::A2::•(bar: "bar", foo: foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart
new file mode 100644
index 0000000..d34d4a6
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart
@@ -0,0 +1,32 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+class A1 {
+  final int foo;
+  A1(this.foo);
+}
+
+class B1 extends A1 {
+  B1(super.foo) : super(); // Ok.
+}
+
+class C1 extends A1 {
+  C1(super.foo) : super(42); // Error.
+}
+
+class A2 {
+  final int foo;
+  final String bar;
+  A2(this.foo, this.bar);
+}
+
+class B2 extends A2 {
+  B2() : super(0, 1, 2); // Error.
+}
+
+class C2 extends A2 {
+  C2(super.foo) : super(); // Error.
+}
+
+main() {}
diff --git a/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.strong.expect b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.strong.expect
new file mode 100644
index 0000000..228f432
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.strong.expect
@@ -0,0 +1,62 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:15:24: Error: Positional super-initializer parameters cannot be used when the super initializer has positional arguments.
+//   C1(super.foo) : super(42); // Error.
+//                        ^
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:15:12: Context: This is the super-initializer parameter.
+//   C1(super.foo) : super(42); // Error.
+//            ^
+//
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:25:15: Error: Too many positional arguments: 2 allowed, but 3 found.
+// Try removing the extra positional arguments.
+//   B2() : super(0, 1, 2); // Error.
+//               ^
+//
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:29:24: Error: Too few positional arguments: 2 required, 1 given.
+//   C2(super.foo) : super(); // Error.
+//                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  final field core::int foo;
+  constructor •(core::int foo) → self::A1
+    : self::A1::foo = foo, super core::Object::•()
+    ;
+}
+class B1 extends self::A1 {
+  constructor •(dynamic foo) → self::B1
+    : super self::A1::•(foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+class C1 extends self::A1 {
+  constructor •(dynamic foo) → self::C1
+    : super self::A1::•(42)
+    ;
+}
+class A2 extends core::Object {
+  final field core::int foo;
+  final field core::String bar;
+  constructor •(core::int foo, core::String bar) → self::A2
+    : self::A2::foo = foo, self::A2::bar = bar, super core::Object::•()
+    ;
+}
+class B2 extends self::A2 {
+  constructor •() → self::B2
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:25:15: Error: Too many positional arguments: 2 allowed, but 3 found.
+Try removing the extra positional arguments.
+  B2() : super(0, 1, 2); // Error.
+              ^"
+    ;
+}
+class C2 extends self::A2 {
+  constructor •(dynamic foo) → self::C2
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:29:24: Error: Too few positional arguments: 2 required, 1 given.
+  C2(super.foo) : super(); // Error.
+                       ^"
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.strong.transformed.expect b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.strong.transformed.expect
new file mode 100644
index 0000000..228f432
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.strong.transformed.expect
@@ -0,0 +1,62 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:15:24: Error: Positional super-initializer parameters cannot be used when the super initializer has positional arguments.
+//   C1(super.foo) : super(42); // Error.
+//                        ^
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:15:12: Context: This is the super-initializer parameter.
+//   C1(super.foo) : super(42); // Error.
+//            ^
+//
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:25:15: Error: Too many positional arguments: 2 allowed, but 3 found.
+// Try removing the extra positional arguments.
+//   B2() : super(0, 1, 2); // Error.
+//               ^
+//
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:29:24: Error: Too few positional arguments: 2 required, 1 given.
+//   C2(super.foo) : super(); // Error.
+//                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  final field core::int foo;
+  constructor •(core::int foo) → self::A1
+    : self::A1::foo = foo, super core::Object::•()
+    ;
+}
+class B1 extends self::A1 {
+  constructor •(dynamic foo) → self::B1
+    : super self::A1::•(foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+class C1 extends self::A1 {
+  constructor •(dynamic foo) → self::C1
+    : super self::A1::•(42)
+    ;
+}
+class A2 extends core::Object {
+  final field core::int foo;
+  final field core::String bar;
+  constructor •(core::int foo, core::String bar) → self::A2
+    : self::A2::foo = foo, self::A2::bar = bar, super core::Object::•()
+    ;
+}
+class B2 extends self::A2 {
+  constructor •() → self::B2
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:25:15: Error: Too many positional arguments: 2 allowed, but 3 found.
+Try removing the extra positional arguments.
+  B2() : super(0, 1, 2); // Error.
+              ^"
+    ;
+}
+class C2 extends self::A2 {
+  constructor •(dynamic foo) → self::C2
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:29:24: Error: Too few positional arguments: 2 required, 1 given.
+  C2(super.foo) : super(); // Error.
+                       ^"
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.textual_outline.expect b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.textual_outline.expect
new file mode 100644
index 0000000..a6fc5bc
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.textual_outline.expect
@@ -0,0 +1,22 @@
+class A1 {
+  final int foo;
+  A1(this.foo);
+}
+class B1 extends A1 {
+  B1(super.foo) : super();
+}
+class C1 extends A1 {
+  C1(super.foo) : super(42);
+}
+class A2 {
+  final int foo;
+  final String bar;
+  A2(this.foo, this.bar);
+}
+class B2 extends A2 {
+  B2() : super(0, 1, 2);
+}
+class C2 extends A2 {
+  C2(super.foo) : super();
+}
+main() {}
diff --git a/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.weak.expect b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.weak.expect
new file mode 100644
index 0000000..228f432
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.weak.expect
@@ -0,0 +1,62 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:15:24: Error: Positional super-initializer parameters cannot be used when the super initializer has positional arguments.
+//   C1(super.foo) : super(42); // Error.
+//                        ^
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:15:12: Context: This is the super-initializer parameter.
+//   C1(super.foo) : super(42); // Error.
+//            ^
+//
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:25:15: Error: Too many positional arguments: 2 allowed, but 3 found.
+// Try removing the extra positional arguments.
+//   B2() : super(0, 1, 2); // Error.
+//               ^
+//
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:29:24: Error: Too few positional arguments: 2 required, 1 given.
+//   C2(super.foo) : super(); // Error.
+//                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  final field core::int foo;
+  constructor •(core::int foo) → self::A1
+    : self::A1::foo = foo, super core::Object::•()
+    ;
+}
+class B1 extends self::A1 {
+  constructor •(dynamic foo) → self::B1
+    : super self::A1::•(foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+class C1 extends self::A1 {
+  constructor •(dynamic foo) → self::C1
+    : super self::A1::•(42)
+    ;
+}
+class A2 extends core::Object {
+  final field core::int foo;
+  final field core::String bar;
+  constructor •(core::int foo, core::String bar) → self::A2
+    : self::A2::foo = foo, self::A2::bar = bar, super core::Object::•()
+    ;
+}
+class B2 extends self::A2 {
+  constructor •() → self::B2
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:25:15: Error: Too many positional arguments: 2 allowed, but 3 found.
+Try removing the extra positional arguments.
+  B2() : super(0, 1, 2); // Error.
+              ^"
+    ;
+}
+class C2 extends self::A2 {
+  constructor •(dynamic foo) → self::C2
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:29:24: Error: Too few positional arguments: 2 required, 1 given.
+  C2(super.foo) : super(); // Error.
+                       ^"
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.weak.modular.expect b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.weak.modular.expect
new file mode 100644
index 0000000..228f432
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.weak.modular.expect
@@ -0,0 +1,62 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:15:24: Error: Positional super-initializer parameters cannot be used when the super initializer has positional arguments.
+//   C1(super.foo) : super(42); // Error.
+//                        ^
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:15:12: Context: This is the super-initializer parameter.
+//   C1(super.foo) : super(42); // Error.
+//            ^
+//
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:25:15: Error: Too many positional arguments: 2 allowed, but 3 found.
+// Try removing the extra positional arguments.
+//   B2() : super(0, 1, 2); // Error.
+//               ^
+//
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:29:24: Error: Too few positional arguments: 2 required, 1 given.
+//   C2(super.foo) : super(); // Error.
+//                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  final field core::int foo;
+  constructor •(core::int foo) → self::A1
+    : self::A1::foo = foo, super core::Object::•()
+    ;
+}
+class B1 extends self::A1 {
+  constructor •(dynamic foo) → self::B1
+    : super self::A1::•(foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+class C1 extends self::A1 {
+  constructor •(dynamic foo) → self::C1
+    : super self::A1::•(42)
+    ;
+}
+class A2 extends core::Object {
+  final field core::int foo;
+  final field core::String bar;
+  constructor •(core::int foo, core::String bar) → self::A2
+    : self::A2::foo = foo, self::A2::bar = bar, super core::Object::•()
+    ;
+}
+class B2 extends self::A2 {
+  constructor •() → self::B2
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:25:15: Error: Too many positional arguments: 2 allowed, but 3 found.
+Try removing the extra positional arguments.
+  B2() : super(0, 1, 2); // Error.
+              ^"
+    ;
+}
+class C2 extends self::A2 {
+  constructor •(dynamic foo) → self::C2
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:29:24: Error: Too few positional arguments: 2 required, 1 given.
+  C2(super.foo) : super(); // Error.
+                       ^"
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.weak.outline.expect b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.weak.outline.expect
new file mode 100644
index 0000000..184b3f4
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.weak.outline.expect
@@ -0,0 +1,33 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  final field core::int foo;
+  constructor •(core::int foo) → self::A1
+    ;
+}
+class B1 extends self::A1 {
+  constructor •(dynamic foo) → self::B1
+    ;
+}
+class C1 extends self::A1 {
+  constructor •(dynamic foo) → self::C1
+    ;
+}
+class A2 extends core::Object {
+  final field core::int foo;
+  final field core::String bar;
+  constructor •(core::int foo, core::String bar) → self::A2
+    ;
+}
+class B2 extends self::A2 {
+  constructor •() → self::B2
+    ;
+}
+class C2 extends self::A2 {
+  constructor •(dynamic foo) → self::C2
+    ;
+}
+static method main() → dynamic
+  ;
diff --git a/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.weak.transformed.expect b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.weak.transformed.expect
new file mode 100644
index 0000000..228f432
--- /dev/null
+++ b/pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart.weak.transformed.expect
@@ -0,0 +1,62 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:15:24: Error: Positional super-initializer parameters cannot be used when the super initializer has positional arguments.
+//   C1(super.foo) : super(42); // Error.
+//                        ^
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:15:12: Context: This is the super-initializer parameter.
+//   C1(super.foo) : super(42); // Error.
+//            ^
+//
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:25:15: Error: Too many positional arguments: 2 allowed, but 3 found.
+// Try removing the extra positional arguments.
+//   B2() : super(0, 1, 2); // Error.
+//               ^
+//
+// pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:29:24: Error: Too few positional arguments: 2 required, 1 given.
+//   C2(super.foo) : super(); // Error.
+//                        ^
+//
+import self as self;
+import "dart:core" as core;
+
+class A1 extends core::Object {
+  final field core::int foo;
+  constructor •(core::int foo) → self::A1
+    : self::A1::foo = foo, super core::Object::•()
+    ;
+}
+class B1 extends self::A1 {
+  constructor •(dynamic foo) → self::B1
+    : super self::A1::•(foo as{TypeError,ForDynamic,ForNonNullableByDefault} core::int)
+    ;
+}
+class C1 extends self::A1 {
+  constructor •(dynamic foo) → self::C1
+    : super self::A1::•(42)
+    ;
+}
+class A2 extends core::Object {
+  final field core::int foo;
+  final field core::String bar;
+  constructor •(core::int foo, core::String bar) → self::A2
+    : self::A2::foo = foo, self::A2::bar = bar, super core::Object::•()
+    ;
+}
+class B2 extends self::A2 {
+  constructor •() → self::B2
+    : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:25:15: Error: Too many positional arguments: 2 allowed, but 3 found.
+Try removing the extra positional arguments.
+  B2() : super(0, 1, 2); // Error.
+              ^"
+    ;
+}
+class C2 extends self::A2 {
+  constructor •(dynamic foo) → self::C2
+    : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/super_parameters/simple_positional_super_parameters.dart:29:24: Error: Too few positional arguments: 2 required, 1 given.
+  C2(super.foo) : super(); // Error.
+                       ^"
+    ;
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/textual_outline.status b/pkg/front_end/testcases/textual_outline.status
index 956276e..5ebd7e2 100644
--- a/pkg/front_end/testcases/textual_outline.status
+++ b/pkg/front_end/testcases/textual_outline.status
@@ -92,6 +92,7 @@
 general/issue47495: FormatterCrash
 general/issue47728_2: FormatterCrash
 general/issue47728_3: FormatterCrash
+general/macro_class: FormatterCrash
 general/many_errors: FormatterCrash
 general/missing_prefix_name: FormatterCrash
 general/new_as_selector: FormatterCrash
@@ -138,6 +139,7 @@
 late_lowering/override_getter_setter: FormatterCrash
 late_lowering/skip_late_final_uninitialized_instance_fields/main: FormatterCrash
 late_lowering/uninitialized_non_nullable_late_fields: FormatterCrash
+macros/macro_class: FormatterCrash
 named_arguments_anywhere/redirecting_constructor_initializers: FormatterCrash
 nnbd/abstract_field_errors: FormatterCrash
 nnbd/covariant_late_field: FormatterCrash
@@ -200,6 +202,9 @@
 regress/issue_41265.crash: Crash
 regress/issue_41265.crash: FormatterCrash
 super_parameters/simple: FormatterCrash
+super_parameters/simple_named_super_parameters: FormatterCrash
+super_parameters/simple_positional_super_parameters: FormatterCrash
+super_parameters/typed_super_parameter: FormatterCrash
 triple_shift/invalid_operator: FormatterCrash
 variance/class_type_parameter_modifier: FormatterCrash
 variance/generic_covariance_sound_variance: FormatterCrash
diff --git a/pkg/front_end/testcases/triple_shift/invalid_operator.dart.weak.modular.expect b/pkg/front_end/testcases/triple_shift/invalid_operator.dart.weak.modular.expect
new file mode 100644
index 0000000..86bba08
--- /dev/null
+++ b/pkg/front_end/testcases/triple_shift/invalid_operator.dart.weak.modular.expect
@@ -0,0 +1,90 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/triple_shift/invalid_operator.dart:6:12: Error: Operator '>>>' should have exactly one parameter.
+//   operator >>>() => true;
+//            ^^^
+//
+// pkg/front_end/testcases/triple_shift/invalid_operator.dart:10:12: Error: Operator '>>>' should have exactly one parameter.
+//   operator >>>(a, b) => true;
+//            ^^^
+//
+// pkg/front_end/testcases/triple_shift/invalid_operator.dart:14:17: Error: An operator can't have optional parameters.
+//   operator >>>([a]) => true;
+//                 ^
+//
+// pkg/front_end/testcases/triple_shift/invalid_operator.dart:18:17: Error: An operator can't have optional parameters.
+//   operator >>>({a}) => true;
+//                 ^
+//
+// pkg/front_end/testcases/triple_shift/invalid_operator.dart:22:12: Error: Operator '>>>' should have exactly one parameter.
+//   operator >>>(a, [b]) => true;
+//            ^^^
+//
+// pkg/front_end/testcases/triple_shift/invalid_operator.dart:26:12: Error: Operator '>>>' should have exactly one parameter.
+//   operator >>>(a, {b}) => true;
+//            ^^^
+//
+// pkg/front_end/testcases/triple_shift/invalid_operator.dart:30:16: Error: Types parameters aren't allowed when defining an operator.
+// Try removing the type parameters.
+//   operator >>><T>(a) => true;
+//                ^
+//
+import self as self;
+import "dart:core" as core;
+
+class Operators1 extends core::Object {
+  synthetic constructor •() → self::Operators1
+    : super core::Object::•()
+    ;
+  operator >>>() → dynamic
+    return true;
+}
+class Operators2 extends core::Object {
+  synthetic constructor •() → self::Operators2
+    : super core::Object::•()
+    ;
+  operator >>>(dynamic a, dynamic b) → dynamic
+    return true;
+}
+class Operators3 extends core::Object {
+  synthetic constructor •() → self::Operators3
+    : super core::Object::•()
+    ;
+  operator >>>([dynamic a = #C1]) → dynamic
+    return true;
+}
+class Operators4 extends core::Object {
+  synthetic constructor •() → self::Operators4
+    : super core::Object::•()
+    ;
+  operator >>>({dynamic a = #C1}) → dynamic
+    return true;
+}
+class Operators5 extends core::Object {
+  synthetic constructor •() → self::Operators5
+    : super core::Object::•()
+    ;
+  operator >>>(dynamic a, [dynamic b = #C1]) → dynamic
+    return true;
+}
+class Operators6 extends core::Object {
+  synthetic constructor •() → self::Operators6
+    : super core::Object::•()
+    ;
+  operator >>>(dynamic a, {dynamic b = #C1}) → dynamic
+    return true;
+}
+class Operators7 extends core::Object {
+  synthetic constructor •() → self::Operators7
+    : super core::Object::•()
+    ;
+  operator >>><T extends core::Object? = dynamic>(dynamic a) → dynamic
+    return true;
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = null
+}
diff --git a/pkg/front_end/testcases/unified_collections/fold_initial.dart.weak.modular.expect b/pkg/front_end/testcases/unified_collections/fold_initial.dart.weak.modular.expect
new file mode 100644
index 0000000..9474a72
--- /dev/null
+++ b/pkg/front_end/testcases/unified_collections/fold_initial.dart.weak.modular.expect
@@ -0,0 +1,206 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+static method foldInitialElements() → void {
+  dynamic element0 = 0;
+  core::num* element1 = 1;
+  core::int* element2 = 2;
+  core::List<core::int*>* list = block {
+    final core::List<core::int*>* #t1 = <core::int*>[element0 as{TypeError,ForDynamic} core::int*, element1 as{TypeError} core::int*, element2];
+    if(true)
+      #t1.{core::List::add}{Invariant}(3){(core::int*) →* void};
+    #t1.{core::List::add}{Invariant}(4){(core::int*) →* void};
+    #t1.{core::List::add}{Invariant}(5){(core::int*) →* void};
+    #t1.{core::List::add}{Invariant}(6){(core::int*) →* void};
+  } =>#t1;
+  self::expect(core::List::generate<core::int*>(7, (core::int* i) → core::int* => i), list);
+  core::Set<core::int*>* set = block {
+    final core::Set<core::int*>* #t2 = col::LinkedHashSet::•<core::int*>();
+    #t2.{core::Set::add}{Invariant}(element0 as{TypeError,ForDynamic} core::int*){(core::int*) →* core::bool*};
+    #t2.{core::Set::add}{Invariant}(element1 as{TypeError} core::int*){(core::int*) →* core::bool*};
+    #t2.{core::Set::add}{Invariant}(element2){(core::int*) →* core::bool*};
+    if(true)
+      #t2.{core::Set::add}{Invariant}(3){(core::int*) →* core::bool*};
+    #t2.{core::Set::add}{Invariant}(4){(core::int*) →* core::bool*};
+    #t2.{core::Set::add}{Invariant}(5){(core::int*) →* core::bool*};
+    #t2.{core::Set::add}{Invariant}(6){(core::int*) →* core::bool*};
+  } =>#t2;
+  self::expect(core::List::generate<core::int*>(7, (core::int* i) → core::int* => i), set.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<core::int*>*});
+}
+static method foldInitialSpread1() → void {
+  dynamic initial = <core::int*>[0, 1, 2];
+  core::List<core::int*>* list = block {
+    final core::List<core::int*>* #t3 = <core::int*>[];
+    for (final dynamic #t4 in initial as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      final core::int* #t5 = #t4 as{TypeError} core::int*;
+      #t3.{core::List::add}{Invariant}(#t5){(core::int*) →* void};
+    }
+    if(true)
+      #t3.{core::List::add}{Invariant}(3){(core::int*) →* void};
+    #t3.{core::List::add}{Invariant}(4){(core::int*) →* void};
+    #t3.{core::List::add}{Invariant}(5){(core::int*) →* void};
+    #t3.{core::List::add}{Invariant}(6){(core::int*) →* void};
+  } =>#t3;
+  self::expect(core::List::generate<core::int*>(7, (core::int* i) → core::int* => i), list);
+  core::Set<core::int*>* set = block {
+    final core::Set<core::int*>* #t6 = col::LinkedHashSet::•<core::int*>();
+    for (final dynamic #t7 in initial as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      final core::int* #t8 = #t7 as{TypeError} core::int*;
+      #t6.{core::Set::add}{Invariant}(#t8){(core::int*) →* core::bool*};
+    }
+    if(true)
+      #t6.{core::Set::add}{Invariant}(3){(core::int*) →* core::bool*};
+    #t6.{core::Set::add}{Invariant}(4){(core::int*) →* core::bool*};
+    #t6.{core::Set::add}{Invariant}(5){(core::int*) →* core::bool*};
+    #t6.{core::Set::add}{Invariant}(6){(core::int*) →* core::bool*};
+  } =>#t6;
+  self::expect(core::List::generate<core::int*>(7, (core::int* i) → core::int* => i), set.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<core::int*>*});
+}
+static method foldInitialSpread2() → void {
+  core::Iterable<core::num*>* initial = <core::num*>[0, 1, 2];
+  core::List<core::int*>* list = block {
+    final core::List<core::int*>* #t9 = <core::int*>[];
+    for (final dynamic #t10 in initial) {
+      final core::int* #t11 = #t10 as{TypeError} core::int*;
+      #t9.{core::List::add}{Invariant}(#t11){(core::int*) →* void};
+    }
+    if(true)
+      #t9.{core::List::add}{Invariant}(3){(core::int*) →* void};
+    #t9.{core::List::add}{Invariant}(4){(core::int*) →* void};
+    #t9.{core::List::add}{Invariant}(5){(core::int*) →* void};
+    #t9.{core::List::add}{Invariant}(6){(core::int*) →* void};
+  } =>#t9;
+  self::expect(core::List::generate<core::int*>(7, (core::int* i) → core::int* => i), list);
+  core::Set<core::int*>* set = block {
+    final core::Set<core::int*>* #t12 = col::LinkedHashSet::•<core::int*>();
+    for (final dynamic #t13 in initial) {
+      final core::int* #t14 = #t13 as{TypeError} core::int*;
+      #t12.{core::Set::add}{Invariant}(#t14){(core::int*) →* core::bool*};
+    }
+    if(true)
+      #t12.{core::Set::add}{Invariant}(3){(core::int*) →* core::bool*};
+    #t12.{core::Set::add}{Invariant}(4){(core::int*) →* core::bool*};
+    #t12.{core::Set::add}{Invariant}(5){(core::int*) →* core::bool*};
+    #t12.{core::Set::add}{Invariant}(6){(core::int*) →* core::bool*};
+  } =>#t12;
+  self::expect(core::List::generate<core::int*>(7, (core::int* i) → core::int* => i), set.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<core::int*>*});
+}
+static method foldInitialSpread3() → void {
+  core::List<core::num*>* initial = <core::num*>[0, 1, 2];
+  core::List<core::int*>* list = block {
+    final core::List<core::int*>* #t15 = <core::int*>[];
+    for (final dynamic #t16 in initial) {
+      final core::int* #t17 = #t16 as{TypeError} core::int*;
+      #t15.{core::List::add}{Invariant}(#t17){(core::int*) →* void};
+    }
+    if(true)
+      #t15.{core::List::add}{Invariant}(3){(core::int*) →* void};
+    #t15.{core::List::add}{Invariant}(4){(core::int*) →* void};
+    #t15.{core::List::add}{Invariant}(5){(core::int*) →* void};
+    #t15.{core::List::add}{Invariant}(6){(core::int*) →* void};
+  } =>#t15;
+  self::expect(core::List::generate<core::int*>(7, (core::int* i) → core::int* => i), list);
+  core::Set<core::int*>* set = block {
+    final core::Set<core::int*>* #t18 = col::LinkedHashSet::•<core::int*>();
+    for (final dynamic #t19 in initial) {
+      final core::int* #t20 = #t19 as{TypeError} core::int*;
+      #t18.{core::Set::add}{Invariant}(#t20){(core::int*) →* core::bool*};
+    }
+    if(true)
+      #t18.{core::Set::add}{Invariant}(3){(core::int*) →* core::bool*};
+    #t18.{core::Set::add}{Invariant}(4){(core::int*) →* core::bool*};
+    #t18.{core::Set::add}{Invariant}(5){(core::int*) →* core::bool*};
+    #t18.{core::Set::add}{Invariant}(6){(core::int*) →* core::bool*};
+  } =>#t18;
+  self::expect(core::List::generate<core::int*>(7, (core::int* i) → core::int* => i), set.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<core::int*>*});
+}
+static method foldInitialSpread4() → void {
+  core::Iterable<core::int*>* initial = <core::int*>[0, 1, 2];
+  core::List<core::int*>* list = block {
+    final core::List<core::int*>* #t21 = core::List::of<core::int*>(initial);
+    if(true)
+      #t21.{core::List::add}{Invariant}(3){(core::int*) →* void};
+    #t21.{core::List::add}{Invariant}(4){(core::int*) →* void};
+    #t21.{core::List::add}{Invariant}(5){(core::int*) →* void};
+    #t21.{core::List::add}{Invariant}(6){(core::int*) →* void};
+  } =>#t21;
+  self::expect(core::List::generate<core::int*>(7, (core::int* i) → core::int* => i), list);
+  core::Set<core::int*>* set = block {
+    final core::Set<core::int*>* #t22 = col::LinkedHashSet::of<core::int*>(initial);
+    if(true)
+      #t22.{core::Set::add}{Invariant}(3){(core::int*) →* core::bool*};
+    #t22.{core::Set::add}{Invariant}(4){(core::int*) →* core::bool*};
+    #t22.{core::Set::add}{Invariant}(5){(core::int*) →* core::bool*};
+    #t22.{core::Set::add}{Invariant}(6){(core::int*) →* core::bool*};
+  } =>#t22;
+  self::expect(core::List::generate<core::int*>(7, (core::int* i) → core::int* => i), set.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<core::int*>*});
+}
+static method foldInitialSpread5() → void {
+  core::List<core::int*>* initial = <core::int*>[0, 1, 2];
+  core::List<core::int*>* list = block {
+    final core::List<core::int*>* #t23 = core::List::of<core::int*>(initial);
+    if(true)
+      #t23.{core::List::add}{Invariant}(3){(core::int*) →* void};
+    #t23.{core::List::add}{Invariant}(4){(core::int*) →* void};
+    #t23.{core::List::add}{Invariant}(5){(core::int*) →* void};
+    #t23.{core::List::add}{Invariant}(6){(core::int*) →* void};
+  } =>#t23;
+  self::expect(core::List::generate<core::int*>(7, (core::int* i) → core::int* => i), list);
+  core::Set<core::int*>* set = block {
+    final core::Set<core::int*>* #t24 = col::LinkedHashSet::of<core::int*>(initial);
+    if(true)
+      #t24.{core::Set::add}{Invariant}(3){(core::int*) →* core::bool*};
+    #t24.{core::Set::add}{Invariant}(4){(core::int*) →* core::bool*};
+    #t24.{core::Set::add}{Invariant}(5){(core::int*) →* core::bool*};
+    #t24.{core::Set::add}{Invariant}(6){(core::int*) →* core::bool*};
+  } =>#t24;
+  self::expect(core::List::generate<core::int*>(7, (core::int* i) → core::int* => i), set.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<core::int*>*});
+}
+static method foldInitialSpread6() → void {
+  core::List<core::int*>* initial = <core::int*>[0, 1, 2];
+  core::List<core::int*>* list = block {
+    final core::List<core::int*>* #t25 = <core::int*>[];
+    final core::Iterable<core::int*>* #t26 = initial;
+    if(!(#t26 == null))
+      #t25.{core::List::addAll}{Invariant}(#t26){(core::Iterable<core::int*>*) →* void};
+    if(true)
+      #t25.{core::List::add}{Invariant}(3){(core::int*) →* void};
+    #t25.{core::List::add}{Invariant}(4){(core::int*) →* void};
+    #t25.{core::List::add}{Invariant}(5){(core::int*) →* void};
+    #t25.{core::List::add}{Invariant}(6){(core::int*) →* void};
+  } =>#t25;
+  self::expect(core::List::generate<core::int*>(7, (core::int* i) → core::int* => i), list);
+  core::Set<core::int*>* set = block {
+    final core::Set<core::int*>* #t27 = col::LinkedHashSet::•<core::int*>();
+    final core::Iterable<core::int*>* #t28 = initial;
+    if(!(#t28 == null))
+      #t27.{core::Set::addAll}{Invariant}(#t28){(core::Iterable<core::int*>*) →* void};
+    if(true)
+      #t27.{core::Set::add}{Invariant}(3){(core::int*) →* core::bool*};
+    #t27.{core::Set::add}{Invariant}(4){(core::int*) →* core::bool*};
+    #t27.{core::Set::add}{Invariant}(5){(core::int*) →* core::bool*};
+    #t27.{core::Set::add}{Invariant}(6){(core::int*) →* core::bool*};
+  } =>#t27;
+  self::expect(core::List::generate<core::int*>(7, (core::int* i) → core::int* => i), set.{core::Iterable::toList}(){({growable: core::bool*}) →* core::List<core::int*>*});
+}
+static method main() → dynamic {
+  self::foldInitialElements();
+  self::foldInitialSpread1();
+  self::foldInitialSpread2();
+  self::foldInitialSpread3();
+  self::foldInitialSpread4();
+  self::foldInitialSpread5();
+  self::foldInitialSpread6();
+}
+static method expect(core::List<dynamic>* list1, core::List<dynamic>* list2) → void {
+  if(!(list1.{core::List::length}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} list2.{core::List::length}{core::int*})) {
+    throw "Unexpected length. Expected ${list1.{core::List::length}{core::int*}}, actual ${list2.{core::List::length}{core::int*}}.";
+  }
+  for (core::int* i = 0; i.{core::num::<}(list1.{core::List::length}{core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+    if(!(list1.{core::List::[]}(i){(core::int*) →* dynamic} =={core::Object::==}{(core::Object*) →* core::bool*} list2.{core::List::[]}(i){(core::int*) →* dynamic})) {
+      throw "Unexpected element at index ${i}. Expected ${list1.{core::List::[]}(i){(core::int*) →* dynamic}}, actual ${list2.{core::List::[]}(i){(core::int*) →* dynamic}}.";
+    }
+  }
+}
diff --git a/pkg/front_end/testcases/unified_collections/invariance.dart.weak.modular.expect b/pkg/front_end/testcases/unified_collections/invariance.dart.weak.modular.expect
new file mode 100644
index 0000000..78bb3e0
--- /dev/null
+++ b/pkg/front_end/testcases/unified_collections/invariance.dart.weak.modular.expect
@@ -0,0 +1,72 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+
+static method main() → dynamic {
+  core::List<core::int*>* list1 = <core::int*>[0];
+  core::List<core::num*>* list2 = <core::num*>[0];
+  dynamic list3 = <core::int*>[0];
+  core::List<core::int*>* list = block {
+    final core::List<core::int*>* #t1 = <core::int*>[0];
+    #t1.{core::List::addAll}{Invariant}(list1){(core::Iterable<core::int*>*) →* void};
+    for (final dynamic #t2 in list2) {
+      final core::int* #t3 = #t2 as{TypeError} core::int*;
+      #t1.{core::List::add}{Invariant}(#t3){(core::int*) →* void};
+    }
+    for (final dynamic #t4 in list3 as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      final core::int* #t5 = #t4 as{TypeError} core::int*;
+      #t1.{core::List::add}{Invariant}(#t5){(core::int*) →* void};
+    }
+    if(true)
+      #t1.{core::List::add}{Invariant}(2){(core::int*) →* void};
+  } =>#t1;
+  core::Set<core::int*>* set1 = block {
+    final core::Set<core::int*>* #t6 = col::LinkedHashSet::•<core::int*>();
+    #t6.{core::Set::add}{Invariant}(0){(core::int*) →* core::bool*};
+  } =>#t6;
+  core::Set<core::num*>* set2 = block {
+    final core::Set<core::num*>* #t7 = col::LinkedHashSet::•<core::num*>();
+    #t7.{core::Set::add}{Invariant}(0){(core::num*) →* core::bool*};
+  } =>#t7;
+  dynamic set3 = block {
+    final core::Set<core::int*>* #t8 = col::LinkedHashSet::•<core::int*>();
+    #t8.{core::Set::add}{Invariant}(0){(core::int*) →* core::bool*};
+  } =>#t8;
+  core::Set<core::int*>* set = block {
+    final core::Set<core::int*>* #t9 = col::LinkedHashSet::•<core::int*>();
+    #t9.{core::Set::add}{Invariant}(0){(core::int*) →* core::bool*};
+    #t9.{core::Set::addAll}{Invariant}(set1){(core::Iterable<core::int*>*) →* void};
+    for (final dynamic #t10 in set2) {
+      final core::int* #t11 = #t10 as{TypeError} core::int*;
+      #t9.{core::Set::add}{Invariant}(#t11){(core::int*) →* core::bool*};
+    }
+    for (final dynamic #t12 in set3 as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      final core::int* #t13 = #t12 as{TypeError} core::int*;
+      #t9.{core::Set::add}{Invariant}(#t13){(core::int*) →* core::bool*};
+    }
+    if(true)
+      #t9.{core::Set::add}{Invariant}(2){(core::int*) →* core::bool*};
+  } =>#t9;
+  core::Map<core::int*, core::String*>* map1 = <core::int*, core::String*>{0: "foo"};
+  core::Map<core::num*, core::Object*>* map2 = <core::num*, core::Object*>{0: "bar"};
+  dynamic map3 = <core::int*, core::String*>{0: "baz"};
+  core::Map<core::int*, core::String*>* map = block {
+    final core::Map<core::int*, core::String*>* #t14 = <core::int*, core::String*>{};
+    #t14.{core::Map::[]=}{Invariant}(0, "foo"){(core::int*, core::String*) →* void};
+    for (final core::MapEntry<core::int*, core::String*>* #t15 in map1.{core::Map::entries}{core::Iterable<core::MapEntry<core::int*, core::String*>>})
+      #t14.{core::Map::[]=}{Invariant}(#t15.{core::MapEntry::key}{core::int*}, #t15.{core::MapEntry::value}{core::String*}){(core::int*, core::String*) →* void};
+    for (final core::MapEntry<dynamic, dynamic>* #t16 in map2.{core::Map::entries}{core::Iterable<core::MapEntry<core::int*, core::String*>>}) {
+      final core::int* #t17 = #t16.{core::MapEntry::key}{dynamic} as{TypeError} core::int*;
+      final core::String* #t18 = #t16.{core::MapEntry::value}{dynamic} as{TypeError} core::String*;
+      #t14.{core::Map::[]=}{Invariant}(#t17, #t18){(core::int*, core::String*) →* void};
+    }
+    for (final core::MapEntry<dynamic, dynamic>* #t19 in (map3 as{TypeError,ForDynamic} core::Map<dynamic, dynamic>*).{core::Map::entries}{core::Iterable<core::MapEntry<core::int*, core::String*>>}) {
+      final core::int* #t20 = #t19.{core::MapEntry::key}{dynamic} as{TypeError} core::int*;
+      final core::String* #t21 = #t19.{core::MapEntry::value}{dynamic} as{TypeError} core::String*;
+      #t14.{core::Map::[]=}{Invariant}(#t20, #t21){(core::int*, core::String*) →* void};
+    }
+    if(true)
+      #t14.{core::Map::[]=}{Invariant}(2, "baz"){(core::int*, core::String*) →* void};
+  } =>#t14;
+}
diff --git a/pkg/front_end/testcases/unified_collections/list_add_all.dart.weak.modular.expect b/pkg/front_end/testcases/unified_collections/list_add_all.dart.weak.modular.expect
new file mode 100644
index 0000000..253e487
--- /dev/null
+++ b/pkg/front_end/testcases/unified_collections/list_add_all.dart.weak.modular.expect
@@ -0,0 +1,155 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method useAddAll() → void {
+  dynamic dynamicList1 = <core::int*>[0, 1, 2];
+  dynamic dynamicList2 = <core::num*>[3, 4, 5];
+  core::Iterable<core::int*>* iterableIntList = <core::int*>[6, 7, 8];
+  core::Iterable<core::num*>* iterableNumList1 = <core::int*>[9, 10, 11];
+  core::Iterable<core::num*>* iterableNumList2 = <core::num*>[12, 13, 14];
+  core::List<core::int*>* intList = <core::int*>[15, 16, 17];
+  core::List<core::num*>* numList1 = <core::int*>[18, 19, 20];
+  core::List<core::num*>* numList2 = <core::num*>[21, 22, 23];
+  core::List<core::int*>* list1 = block {
+    final core::List<core::int*>* #t1 = <core::int*>[];
+    for (final dynamic #t2 in dynamicList1 as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      final core::int* #t3 = #t2 as{TypeError} core::int*;
+      #t1.{core::List::add}{Invariant}(#t3){(core::int*) →* void};
+    }
+    for (final dynamic #t4 in dynamicList2 as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      final core::int* #t5 = #t4 as{TypeError} core::int*;
+      #t1.{core::List::add}{Invariant}(#t5){(core::int*) →* void};
+    }
+    #t1.{core::List::addAll}{Invariant}(iterableIntList){(core::Iterable<core::int*>*) →* void};
+    for (final dynamic #t6 in iterableNumList1) {
+      final core::int* #t7 = #t6 as{TypeError} core::int*;
+      #t1.{core::List::add}{Invariant}(#t7){(core::int*) →* void};
+    }
+    for (final dynamic #t8 in iterableNumList2) {
+      final core::int* #t9 = #t8 as{TypeError} core::int*;
+      #t1.{core::List::add}{Invariant}(#t9){(core::int*) →* void};
+    }
+    #t1.{core::List::addAll}{Invariant}(intList){(core::Iterable<core::int*>*) →* void};
+    for (final dynamic #t10 in numList1) {
+      final core::int* #t11 = #t10 as{TypeError} core::int*;
+      #t1.{core::List::add}{Invariant}(#t11){(core::int*) →* void};
+    }
+    for (final dynamic #t12 in numList2) {
+      final core::int* #t13 = #t12 as{TypeError} core::int*;
+      #t1.{core::List::add}{Invariant}(#t13){(core::int*) →* void};
+    }
+  } =>#t1;
+  self::expect(core::List::generate<core::int*>(24, (core::int* i) → core::int* => i), list1);
+  core::List<core::num*>* list2 = block {
+    final core::List<core::num*>* #t14 = <core::num*>[];
+    for (final dynamic #t15 in dynamicList1 as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      final core::num* #t16 = #t15 as{TypeError} core::num*;
+      #t14.{core::List::add}{Invariant}(#t16){(core::num*) →* void};
+    }
+    for (final dynamic #t17 in dynamicList2 as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      final core::num* #t18 = #t17 as{TypeError} core::num*;
+      #t14.{core::List::add}{Invariant}(#t18){(core::num*) →* void};
+    }
+    #t14.{core::List::addAll}{Invariant}(iterableIntList){(core::Iterable<core::num*>*) →* void};
+    #t14.{core::List::addAll}{Invariant}(iterableNumList1){(core::Iterable<core::num*>*) →* void};
+    #t14.{core::List::addAll}{Invariant}(iterableNumList2){(core::Iterable<core::num*>*) →* void};
+    #t14.{core::List::addAll}{Invariant}(intList){(core::Iterable<core::num*>*) →* void};
+    #t14.{core::List::addAll}{Invariant}(numList1){(core::Iterable<core::num*>*) →* void};
+    #t14.{core::List::addAll}{Invariant}(numList2){(core::Iterable<core::num*>*) →* void};
+  } =>#t14;
+  self::expect(core::List::generate<core::num*>(24, (core::int* i) → core::int* => i), list2);
+  core::List<core::int*>* list3 = block {
+    final core::List<core::int*>* #t19 = <core::int*>[];
+    final core::Iterable<dynamic>* #t20 = dynamicList1 as{TypeError,ForDynamic} core::Iterable<dynamic>*;
+    if(!(#t20 == null))
+      for (final dynamic #t21 in #t20) {
+        final core::int* #t22 = #t21 as{TypeError} core::int*;
+        #t19.{core::List::add}{Invariant}(#t22){(core::int*) →* void};
+      }
+    final core::Iterable<dynamic>* #t23 = dynamicList2 as{TypeError,ForDynamic} core::Iterable<dynamic>*;
+    if(!(#t23 == null))
+      for (final dynamic #t24 in #t23) {
+        final core::int* #t25 = #t24 as{TypeError} core::int*;
+        #t19.{core::List::add}{Invariant}(#t25){(core::int*) →* void};
+      }
+    final core::Iterable<core::int*>* #t26 = iterableIntList;
+    if(!(#t26 == null))
+      #t19.{core::List::addAll}{Invariant}(#t26){(core::Iterable<core::int*>*) →* void};
+    final core::Iterable<dynamic>* #t27 = iterableNumList1;
+    if(!(#t27 == null))
+      for (final dynamic #t28 in #t27) {
+        final core::int* #t29 = #t28 as{TypeError} core::int*;
+        #t19.{core::List::add}{Invariant}(#t29){(core::int*) →* void};
+      }
+    final core::Iterable<dynamic>* #t30 = iterableNumList2;
+    if(!(#t30 == null))
+      for (final dynamic #t31 in #t30) {
+        final core::int* #t32 = #t31 as{TypeError} core::int*;
+        #t19.{core::List::add}{Invariant}(#t32){(core::int*) →* void};
+      }
+    final core::Iterable<core::int*>* #t33 = intList;
+    if(!(#t33 == null))
+      #t19.{core::List::addAll}{Invariant}(#t33){(core::Iterable<core::int*>*) →* void};
+    final core::Iterable<dynamic>* #t34 = numList1;
+    if(!(#t34 == null))
+      for (final dynamic #t35 in #t34) {
+        final core::int* #t36 = #t35 as{TypeError} core::int*;
+        #t19.{core::List::add}{Invariant}(#t36){(core::int*) →* void};
+      }
+    final core::Iterable<dynamic>* #t37 = numList2;
+    if(!(#t37 == null))
+      for (final dynamic #t38 in #t37) {
+        final core::int* #t39 = #t38 as{TypeError} core::int*;
+        #t19.{core::List::add}{Invariant}(#t39){(core::int*) →* void};
+      }
+  } =>#t19;
+  self::expect(core::List::generate<core::int*>(24, (core::int* i) → core::int* => i), list3);
+  core::List<core::num*>* list4 = block {
+    final core::List<core::num*>* #t40 = <core::num*>[];
+    final core::Iterable<dynamic>* #t41 = dynamicList1 as{TypeError,ForDynamic} core::Iterable<dynamic>*;
+    if(!(#t41 == null))
+      for (final dynamic #t42 in #t41) {
+        final core::num* #t43 = #t42 as{TypeError} core::num*;
+        #t40.{core::List::add}{Invariant}(#t43){(core::num*) →* void};
+      }
+    final core::Iterable<dynamic>* #t44 = dynamicList2 as{TypeError,ForDynamic} core::Iterable<dynamic>*;
+    if(!(#t44 == null))
+      for (final dynamic #t45 in #t44) {
+        final core::num* #t46 = #t45 as{TypeError} core::num*;
+        #t40.{core::List::add}{Invariant}(#t46){(core::num*) →* void};
+      }
+    final core::Iterable<core::num*>* #t47 = iterableIntList;
+    if(!(#t47 == null))
+      #t40.{core::List::addAll}{Invariant}(#t47){(core::Iterable<core::num*>*) →* void};
+    final core::Iterable<core::num*>* #t48 = iterableNumList1;
+    if(!(#t48 == null))
+      #t40.{core::List::addAll}{Invariant}(#t48){(core::Iterable<core::num*>*) →* void};
+    final core::Iterable<core::num*>* #t49 = iterableNumList2;
+    if(!(#t49 == null))
+      #t40.{core::List::addAll}{Invariant}(#t49){(core::Iterable<core::num*>*) →* void};
+    final core::Iterable<core::num*>* #t50 = intList;
+    if(!(#t50 == null))
+      #t40.{core::List::addAll}{Invariant}(#t50){(core::Iterable<core::num*>*) →* void};
+    final core::Iterable<core::num*>* #t51 = numList1;
+    if(!(#t51 == null))
+      #t40.{core::List::addAll}{Invariant}(#t51){(core::Iterable<core::num*>*) →* void};
+    final core::Iterable<core::num*>* #t52 = numList2;
+    if(!(#t52 == null))
+      #t40.{core::List::addAll}{Invariant}(#t52){(core::Iterable<core::num*>*) →* void};
+  } =>#t40;
+  self::expect(core::List::generate<core::num*>(24, (core::int* i) → core::int* => i), list4);
+}
+static method main() → dynamic {
+  self::useAddAll();
+}
+static method expect(core::List<dynamic>* list1, core::List<dynamic>* list2) → void {
+  if(!(list1.{core::List::length}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} list2.{core::List::length}{core::int*})) {
+    throw "Unexpected length. Expected ${list1.{core::List::length}{core::int*}}, actual ${list2.{core::List::length}{core::int*}}.";
+  }
+  for (core::int* i = 0; i.{core::num::<}(list1.{core::List::length}{core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*}) {
+    if(!(list1.{core::List::[]}(i){(core::int*) →* dynamic} =={core::Object::==}{(core::Object*) →* core::bool*} list2.{core::List::[]}(i){(core::int*) →* dynamic})) {
+      throw "Unexpected element at index ${i}. Expected ${list1.{core::List::[]}(i){(core::int*) →* dynamic}}, actual ${list2.{core::List::[]}(i){(core::int*) →* dynamic}}.";
+    }
+  }
+}
diff --git a/pkg/front_end/testcases/unified_collections/list_add_all_nnbd.dart.weak.modular.expect b/pkg/front_end/testcases/unified_collections/list_add_all_nnbd.dart.weak.modular.expect
new file mode 100644
index 0000000..c6f63bf
--- /dev/null
+++ b/pkg/front_end/testcases/unified_collections/list_add_all_nnbd.dart.weak.modular.expect
@@ -0,0 +1,124 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+static method useAddAll() → void {
+  dynamic dynamicList1 = <core::int>[0, 1, 2];
+  dynamic dynamicList2 = <core::num>[3, 4, 5];
+  dynamic dynamicList3 = <core::int?>[6, 7, 8];
+  core::Iterable<core::int> iterableIntList = <core::int>[9, 10, 11];
+  core::List<core::int> intList = <core::int>[12, 13, 14];
+  core::List<core::int> list1 = block {
+    final core::List<core::int> #t1 = <core::int>[];
+    for (final dynamic #t2 in dynamicList1 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>) {
+      final core::int #t3 = #t2 as{TypeError,ForNonNullableByDefault} core::int;
+      #t1.{core::List::add}{Invariant}(#t3){(core::int) → void};
+    }
+    for (final dynamic #t4 in dynamicList2 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>) {
+      final core::int #t5 = #t4 as{TypeError,ForNonNullableByDefault} core::int;
+      #t1.{core::List::add}{Invariant}(#t5){(core::int) → void};
+    }
+    for (final dynamic #t6 in dynamicList3 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>) {
+      final core::int #t7 = #t6 as{TypeError,ForNonNullableByDefault} core::int;
+      #t1.{core::List::add}{Invariant}(#t7){(core::int) → void};
+    }
+    #t1.{core::List::addAll}{Invariant}(iterableIntList){(core::Iterable<core::int>) → void};
+    #t1.{core::List::addAll}{Invariant}(intList){(core::Iterable<core::int>) → void};
+  } =>#t1;
+  self::expect(core::List::generate<core::int>(15, (core::int i) → core::int => i), list1);
+  core::List<core::num> list2 = block {
+    final core::List<core::num> #t8 = <core::num>[];
+    for (final dynamic #t9 in dynamicList1 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>) {
+      final core::num #t10 = #t9 as{TypeError,ForNonNullableByDefault} core::num;
+      #t8.{core::List::add}{Invariant}(#t10){(core::num) → void};
+    }
+    for (final dynamic #t11 in dynamicList2 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>) {
+      final core::num #t12 = #t11 as{TypeError,ForNonNullableByDefault} core::num;
+      #t8.{core::List::add}{Invariant}(#t12){(core::num) → void};
+    }
+    for (final dynamic #t13 in dynamicList3 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>) {
+      final core::num #t14 = #t13 as{TypeError,ForNonNullableByDefault} core::num;
+      #t8.{core::List::add}{Invariant}(#t14){(core::num) → void};
+    }
+    #t8.{core::List::addAll}{Invariant}(iterableIntList){(core::Iterable<core::num>) → void};
+    #t8.{core::List::addAll}{Invariant}(intList){(core::Iterable<core::num>) → void};
+  } =>#t8;
+  self::expect(core::List::generate<core::num>(15, (core::int i) → core::int => i), list2);
+}
+static method useAddAllNullable() → void {
+  dynamic dynamicList1 = <core::int>[0, 1, 2];
+  dynamic dynamicList2 = <core::num>[3, 4, 5];
+  dynamic dynamicList3 = <core::int?>[6, 7, 8];
+  core::Iterable<core::int>? iterableIntList = true ?{core::List<core::int>?} <core::int>[9, 10, 11] : null;
+  core::List<core::int>? intList = true ?{core::List<core::int>?} <core::int>[12, 13, 14] : null;
+  core::List<core::int> list1 = block {
+    final core::List<core::int> #t15 = <core::int>[];
+    final core::Iterable<dynamic>? #t16 = dynamicList1 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>?;
+    if(!(#t16 == null))
+      for (final dynamic #t17 in #t16{core::Iterable<dynamic>}) {
+        final core::int #t18 = #t17 as{TypeError,ForNonNullableByDefault} core::int;
+        #t15.{core::List::add}{Invariant}(#t18){(core::int) → void};
+      }
+    final core::Iterable<dynamic>? #t19 = dynamicList2 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>?;
+    if(!(#t19 == null))
+      for (final dynamic #t20 in #t19{core::Iterable<dynamic>}) {
+        final core::int #t21 = #t20 as{TypeError,ForNonNullableByDefault} core::int;
+        #t15.{core::List::add}{Invariant}(#t21){(core::int) → void};
+      }
+    final core::Iterable<dynamic>? #t22 = dynamicList3 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>?;
+    if(!(#t22 == null))
+      for (final dynamic #t23 in #t22{core::Iterable<dynamic>}) {
+        final core::int #t24 = #t23 as{TypeError,ForNonNullableByDefault} core::int;
+        #t15.{core::List::add}{Invariant}(#t24){(core::int) → void};
+      }
+    final core::Iterable<core::int>? #t25 = iterableIntList;
+    if(!(#t25 == null))
+      #t15.{core::List::addAll}{Invariant}(#t25{core::Iterable<core::int>}){(core::Iterable<core::int>) → void};
+    final core::Iterable<core::int>? #t26 = intList;
+    if(!(#t26 == null))
+      #t15.{core::List::addAll}{Invariant}(#t26{core::Iterable<core::int>}){(core::Iterable<core::int>) → void};
+  } =>#t15;
+  self::expect(core::List::generate<core::int>(15, (core::int i) → core::int => i), list1);
+  core::List<core::num> list2 = block {
+    final core::List<core::num> #t27 = <core::num>[];
+    final core::Iterable<dynamic>? #t28 = dynamicList1 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>?;
+    if(!(#t28 == null))
+      for (final dynamic #t29 in #t28{core::Iterable<dynamic>}) {
+        final core::num #t30 = #t29 as{TypeError,ForNonNullableByDefault} core::num;
+        #t27.{core::List::add}{Invariant}(#t30){(core::num) → void};
+      }
+    final core::Iterable<dynamic>? #t31 = dynamicList2 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>?;
+    if(!(#t31 == null))
+      for (final dynamic #t32 in #t31{core::Iterable<dynamic>}) {
+        final core::num #t33 = #t32 as{TypeError,ForNonNullableByDefault} core::num;
+        #t27.{core::List::add}{Invariant}(#t33){(core::num) → void};
+      }
+    final core::Iterable<dynamic>? #t34 = dynamicList3 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>?;
+    if(!(#t34 == null))
+      for (final dynamic #t35 in #t34{core::Iterable<dynamic>}) {
+        final core::num #t36 = #t35 as{TypeError,ForNonNullableByDefault} core::num;
+        #t27.{core::List::add}{Invariant}(#t36){(core::num) → void};
+      }
+    final core::Iterable<core::num>? #t37 = iterableIntList;
+    if(!(#t37 == null))
+      #t27.{core::List::addAll}{Invariant}(#t37{core::Iterable<core::num>}){(core::Iterable<core::num>) → void};
+    final core::Iterable<core::num>? #t38 = intList;
+    if(!(#t38 == null))
+      #t27.{core::List::addAll}{Invariant}(#t38{core::Iterable<core::num>}){(core::Iterable<core::num>) → void};
+  } =>#t27;
+  self::expect(core::List::generate<core::num>(15, (core::int i) → core::int => i), list2);
+}
+static method main() → dynamic {
+  self::useAddAll();
+  self::useAddAllNullable();
+}
+static method expect(core::List<dynamic> list1, core::List<dynamic> list2) → void {
+  if(!(list1.{core::List::length}{core::int} =={core::num::==}{(core::Object) → core::bool} list2.{core::List::length}{core::int})) {
+    throw "Unexpected length. Expected ${list1.{core::List::length}{core::int}}, actual ${list2.{core::List::length}{core::int}}.";
+  }
+  for (core::int i = 0; i.{core::num::<}(list1.{core::List::length}{core::int}){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+    if(!(list1.{core::List::[]}(i){(core::int) → dynamic} =={core::Object::==}{(core::Object) → core::bool} list2.{core::List::[]}(i){(core::int) → dynamic})) {
+      throw "Unexpected element at index ${i}. Expected ${list1.{core::List::[]}(i){(core::int) → dynamic}}, actual ${list2.{core::List::[]}(i){(core::int) → dynamic}}.";
+    }
+  }
+}
diff --git a/pkg/front_end/testcases/unified_collections/mixed_entries.dart.weak.modular.expect b/pkg/front_end/testcases/unified_collections/mixed_entries.dart.weak.modular.expect
new file mode 100644
index 0000000..2ccee62
--- /dev/null
+++ b/pkg/front_end/testcases/unified_collections/mixed_entries.dart.weak.modular.expect
@@ -0,0 +1,176 @@
+library;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/unified_collections/mixed_entries.dart:35:32: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+// var error4 = {if (b) 0: 1 else for (var a in list) a};
+//                                ^
+//
+// pkg/front_end/testcases/unified_collections/mixed_entries.dart:36:22: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+// var error5 = {if (b) for (var a in list) a else 0: 1};
+//                      ^
+//
+// pkg/front_end/testcases/unified_collections/mixed_entries.dart:43:32: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+// var error8 = {if (b) 0: 1 else for (var i = 0; i < list.length; i++) list[i]};
+//                                ^
+//
+// pkg/front_end/testcases/unified_collections/mixed_entries.dart:44:22: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+// var error9 = {if (b) for (var i = 0; i < list.length; i++) list[i] else 0: 1};
+//                      ^
+//
+// pkg/front_end/testcases/unified_collections/mixed_entries.dart:37:14: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+// var error6 = {
+//              ^
+//
+// pkg/front_end/testcases/unified_collections/mixed_entries.dart:40:14: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+// var error7 = {
+//              ^
+//
+// pkg/front_end/testcases/unified_collections/mixed_entries.dart:45:15: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+// var error10 = {
+//               ^
+//
+// pkg/front_end/testcases/unified_collections/mixed_entries.dart:48:15: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+// var error11 = {
+//               ^
+//
+// pkg/front_end/testcases/unified_collections/mixed_entries.dart:51:15: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+// var error12 = {
+//               ^
+//
+import self as self;
+import "dart:core" as core;
+
+static field core::bool* b = false;
+static field core::List<dynamic>* list = <dynamic>[];
+static field core::Map<dynamic, dynamic>* map0 = <dynamic, dynamic>{};
+static field core::Map<dynamic, dynamic>* map1 = block {
+  final core::Map<dynamic, dynamic>* #t1 = <dynamic, dynamic>{};
+  if(self::b)
+    #t1.{core::Map::[]=}{Invariant}(0, 1){(dynamic, dynamic) →* void};
+  else
+    for (final core::MapEntry<dynamic, dynamic>* #t2 in self::map0.{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, dynamic>>})
+      #t1.{core::Map::[]=}{Invariant}(#t2.{core::MapEntry::key}{dynamic}, #t2.{core::MapEntry::value}{dynamic}){(dynamic, dynamic) →* void};
+} =>#t1;
+static field core::Map<dynamic, dynamic>* map2 = block {
+  final core::Map<dynamic, dynamic>* #t3 = <dynamic, dynamic>{};
+  if(self::b)
+    for (final core::MapEntry<dynamic, dynamic>* #t4 in self::map0.{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, dynamic>>})
+      #t3.{core::Map::[]=}{Invariant}(#t4.{core::MapEntry::key}{dynamic}, #t4.{core::MapEntry::value}{dynamic}){(dynamic, dynamic) →* void};
+  else
+    #t3.{core::Map::[]=}{Invariant}(0, 1){(dynamic, dynamic) →* void};
+} =>#t3;
+static field core::Map<dynamic, dynamic>* map3 = block {
+  final core::Map<dynamic, dynamic>* #t5 = <dynamic, dynamic>{};
+  if(self::b)
+    for (final core::MapEntry<dynamic, dynamic>* #t6 in self::map0.{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, dynamic>>})
+      #t5.{core::Map::[]=}{Invariant}(#t6.{core::MapEntry::key}{dynamic}, #t6.{core::MapEntry::value}{dynamic}){(dynamic, dynamic) →* void};
+  else
+    for (final core::MapEntry<dynamic, dynamic>* #t7 in self::map0.{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, dynamic>>})
+      #t5.{core::Map::[]=}{Invariant}(#t7.{core::MapEntry::key}{dynamic}, #t7.{core::MapEntry::value}{dynamic}){(dynamic, dynamic) →* void};
+} =>#t5;
+static field core::Map<dynamic, core::int*>* map4 = block {
+  final core::Map<dynamic, core::int*>* #t8 = <dynamic, core::int*>{};
+  if(self::b)
+    #t8.{core::Map::[]=}{Invariant}(0, 1){(dynamic, core::int*) →* void};
+  else
+    for (dynamic a in self::list)
+      #t8.{core::Map::[]=}{Invariant}(a, 1){(dynamic, core::int*) →* void};
+} =>#t8;
+static field core::Map<dynamic, core::int*>* map5 = block {
+  final core::Map<dynamic, core::int*>* #t9 = <dynamic, core::int*>{};
+  if(self::b)
+    for (dynamic a in self::list)
+      #t9.{core::Map::[]=}{Invariant}(a, 1){(dynamic, core::int*) →* void};
+  else
+    #t9.{core::Map::[]=}{Invariant}(0, 1){(dynamic, core::int*) →* void};
+} =>#t9;
+static field core::Map<dynamic, core::int*>* map6 = block {
+  final core::Map<dynamic, core::int*>* #t10 = <dynamic, core::int*>{};
+  if(self::b)
+    #t10.{core::Map::[]=}{Invariant}(0, 1){(dynamic, core::int*) →* void};
+  else
+    for (dynamic a in self::list)
+      for (final core::MapEntry<dynamic, core::int*>* #t11 in <dynamic, core::int*>{a: 1}.{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, core::int*>>})
+        #t10.{core::Map::[]=}{Invariant}(#t11.{core::MapEntry::key}{dynamic}, #t11.{core::MapEntry::value}{core::int*}){(dynamic, core::int*) →* void};
+} =>#t10;
+static field core::Map<dynamic, core::int*>* map7 = block {
+  final core::Map<dynamic, core::int*>* #t12 = <dynamic, core::int*>{};
+  if(self::b)
+    for (dynamic a in self::list)
+      for (final core::MapEntry<dynamic, core::int*>* #t13 in <dynamic, core::int*>{a: 1}.{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, core::int*>>})
+        #t12.{core::Map::[]=}{Invariant}(#t13.{core::MapEntry::key}{dynamic}, #t13.{core::MapEntry::value}{core::int*}){(dynamic, core::int*) →* void};
+  else
+    #t12.{core::Map::[]=}{Invariant}(0, 1){(dynamic, core::int*) →* void};
+} =>#t12;
+static field core::Map<dynamic, core::int*>* map8 = block {
+  final core::Map<dynamic, core::int*>* #t14 = <dynamic, core::int*>{};
+  if(self::b)
+    #t14.{core::Map::[]=}{Invariant}(0, 1){(dynamic, core::int*) →* void};
+  else
+    for (core::int* i = 0; i.{core::num::<}(self::list.{core::List::length}{core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t14.{core::Map::[]=}{Invariant}(self::list.{core::List::[]}(i){(core::int*) →* dynamic}, 1){(dynamic, core::int*) →* void};
+} =>#t14;
+static field core::Map<dynamic, core::int*>* map9 = block {
+  final core::Map<dynamic, core::int*>* #t15 = <dynamic, core::int*>{};
+  if(self::b)
+    for (core::int* i = 0; i.{core::num::<}(self::list.{core::List::length}{core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      #t15.{core::Map::[]=}{Invariant}(self::list.{core::List::[]}(i){(core::int*) →* dynamic}, 1){(dynamic, core::int*) →* void};
+  else
+    #t15.{core::Map::[]=}{Invariant}(0, 1){(dynamic, core::int*) →* void};
+} =>#t15;
+static field core::Map<dynamic, core::int*>* map10 = block {
+  final core::Map<dynamic, core::int*>* #t16 = <dynamic, core::int*>{};
+  if(self::b)
+    #t16.{core::Map::[]=}{Invariant}(0, 1){(dynamic, core::int*) →* void};
+  else
+    for (core::int* i = 0; i.{core::num::<}(self::list.{core::List::length}{core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      for (final core::MapEntry<dynamic, core::int*>* #t17 in <dynamic, core::int*>{self::list.{core::List::[]}(i){(core::int*) →* dynamic}: 1}.{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, core::int*>>})
+        #t16.{core::Map::[]=}{Invariant}(#t17.{core::MapEntry::key}{dynamic}, #t17.{core::MapEntry::value}{core::int*}){(dynamic, core::int*) →* void};
+} =>#t16;
+static field core::Map<dynamic, core::int*>* map11 = block {
+  final core::Map<dynamic, core::int*>* #t18 = <dynamic, core::int*>{};
+  if(self::b)
+    for (core::int* i = 0; i.{core::num::<}(self::list.{core::List::length}{core::int*}){(core::num*) →* core::bool*}; i = i.{core::num::+}(1){(core::num*) →* core::int*})
+      for (final core::MapEntry<dynamic, core::int*>* #t19 in <dynamic, core::int*>{self::list.{core::List::[]}(i){(core::int*) →* dynamic}: 1}.{core::Map::entries}{core::Iterable<core::MapEntry<dynamic, core::int*>>})
+        #t18.{core::Map::[]=}{Invariant}(#t19.{core::MapEntry::key}{dynamic}, #t19.{core::MapEntry::value}{core::int*}){(dynamic, core::int*) →* void};
+  else
+    #t18.{core::Map::[]=}{Invariant}(0, 1){(dynamic, core::int*) →* void};
+} =>#t18;
+static field core::Map<core::int*, core::int*>* map12 = block {
+  final core::Map<core::int*, core::int*>* #t20 = <core::int*, core::int*>{};
+  if(self::b)
+    #t20.{core::Map::[]=}{Invariant}(0, 1){(core::int*, core::int*) →* void};
+  else
+    if(self::b)
+      for (final core::MapEntry<core::int*, core::int*>* #t21 in <core::int*, core::int*>{0: 1}.{core::Map::entries}{core::Iterable<core::MapEntry<core::int*, core::int*>>})
+        #t20.{core::Map::[]=}{Invariant}(#t21.{core::MapEntry::key}{core::int*}, #t21.{core::MapEntry::value}{core::int*}){(core::int*, core::int*) →* void};
+} =>#t20;
+static field core::Map<invalid-type, Null>* error4 = <invalid-type, Null>{invalid-expression "pkg/front_end/testcases/unified_collections/mixed_entries.dart:35:32: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+var error4 = {if (b) 0: 1 else for (var a in list) a};
+                               ^": null};
+static field core::Map<invalid-type, Null>* error5 = <invalid-type, Null>{invalid-expression "pkg/front_end/testcases/unified_collections/mixed_entries.dart:36:22: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+var error5 = {if (b) for (var a in list) a else 0: 1};
+                     ^": null};
+static field Null error6 = invalid-expression "pkg/front_end/testcases/unified_collections/mixed_entries.dart:37:14: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+var error6 = {
+             ^";
+static field Null error7 = invalid-expression "pkg/front_end/testcases/unified_collections/mixed_entries.dart:40:14: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+var error7 = {
+             ^";
+static field core::Map<invalid-type, Null>* error8 = <invalid-type, Null>{invalid-expression "pkg/front_end/testcases/unified_collections/mixed_entries.dart:43:32: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+var error8 = {if (b) 0: 1 else for (var i = 0; i < list.length; i++) list[i]};
+                               ^": null};
+static field core::Map<invalid-type, Null>* error9 = <invalid-type, Null>{invalid-expression "pkg/front_end/testcases/unified_collections/mixed_entries.dart:44:22: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+var error9 = {if (b) for (var i = 0; i < list.length; i++) list[i] else 0: 1};
+                     ^": null};
+static field Null error10 = invalid-expression "pkg/front_end/testcases/unified_collections/mixed_entries.dart:45:15: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+var error10 = {
+              ^";
+static field Null error11 = invalid-expression "pkg/front_end/testcases/unified_collections/mixed_entries.dart:48:15: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+var error11 = {
+              ^";
+static field Null error12 = invalid-expression "pkg/front_end/testcases/unified_collections/mixed_entries.dart:51:15: Error: Both Iterable and Map spread elements encountered in ambiguous literal.
+var error12 = {
+              ^";
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/unified_collections/set_add_all.dart.weak.modular.expect b/pkg/front_end/testcases/unified_collections/set_add_all.dart.weak.modular.expect
new file mode 100644
index 0000000..5fe44fb
--- /dev/null
+++ b/pkg/front_end/testcases/unified_collections/set_add_all.dart.weak.modular.expect
@@ -0,0 +1,197 @@
+library;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+import "dart:_internal" as _in;
+
+static method useAddAll() → void {
+  dynamic dynamicSet1 = block {
+    final core::Set<core::int*>* #t1 = col::LinkedHashSet::•<core::int*>();
+    #t1.{core::Set::add}{Invariant}(0){(core::int*) →* core::bool*};
+    #t1.{core::Set::add}{Invariant}(1){(core::int*) →* core::bool*};
+    #t1.{core::Set::add}{Invariant}(2){(core::int*) →* core::bool*};
+  } =>#t1;
+  dynamic dynamicSet2 = block {
+    final core::Set<core::num*>* #t2 = col::LinkedHashSet::•<core::num*>();
+    #t2.{core::Set::add}{Invariant}(3){(core::num*) →* core::bool*};
+    #t2.{core::Set::add}{Invariant}(4){(core::num*) →* core::bool*};
+    #t2.{core::Set::add}{Invariant}(5){(core::num*) →* core::bool*};
+  } =>#t2;
+  core::Iterable<core::int*>* iterableIntSet = block {
+    final core::Set<core::int*>* #t3 = col::LinkedHashSet::•<core::int*>();
+    #t3.{core::Set::add}{Invariant}(6){(core::int*) →* core::bool*};
+    #t3.{core::Set::add}{Invariant}(7){(core::int*) →* core::bool*};
+    #t3.{core::Set::add}{Invariant}(8){(core::int*) →* core::bool*};
+  } =>#t3;
+  core::Iterable<core::num*>* iterableNumSet1 = block {
+    final core::Set<core::int*>* #t4 = col::LinkedHashSet::•<core::int*>();
+    #t4.{core::Set::add}{Invariant}(9){(core::int*) →* core::bool*};
+    #t4.{core::Set::add}{Invariant}(10){(core::int*) →* core::bool*};
+    #t4.{core::Set::add}{Invariant}(11){(core::int*) →* core::bool*};
+  } =>#t4;
+  core::Iterable<core::num*>* iterableNumSet2 = block {
+    final core::Set<core::num*>* #t5 = col::LinkedHashSet::•<core::num*>();
+    #t5.{core::Set::add}{Invariant}(12){(core::num*) →* core::bool*};
+    #t5.{core::Set::add}{Invariant}(13){(core::num*) →* core::bool*};
+    #t5.{core::Set::add}{Invariant}(14){(core::num*) →* core::bool*};
+  } =>#t5;
+  core::Set<core::int*>* intSet = block {
+    final core::Set<core::int*>* #t6 = col::LinkedHashSet::•<core::int*>();
+    #t6.{core::Set::add}{Invariant}(15){(core::int*) →* core::bool*};
+    #t6.{core::Set::add}{Invariant}(16){(core::int*) →* core::bool*};
+    #t6.{core::Set::add}{Invariant}(17){(core::int*) →* core::bool*};
+  } =>#t6;
+  core::Set<core::num*>* numSet1 = block {
+    final core::Set<core::int*>* #t7 = col::LinkedHashSet::•<core::int*>();
+    #t7.{core::Set::add}{Invariant}(18){(core::int*) →* core::bool*};
+    #t7.{core::Set::add}{Invariant}(19){(core::int*) →* core::bool*};
+    #t7.{core::Set::add}{Invariant}(20){(core::int*) →* core::bool*};
+  } =>#t7;
+  core::Set<core::num*>* numSet2 = block {
+    final core::Set<core::num*>* #t8 = col::LinkedHashSet::•<core::num*>();
+    #t8.{core::Set::add}{Invariant}(21){(core::num*) →* core::bool*};
+    #t8.{core::Set::add}{Invariant}(22){(core::num*) →* core::bool*};
+    #t8.{core::Set::add}{Invariant}(23){(core::num*) →* core::bool*};
+  } =>#t8;
+  core::Set<core::int*>* set1 = block {
+    final core::Set<core::int*>* #t9 = col::LinkedHashSet::•<core::int*>();
+    for (final dynamic #t10 in dynamicSet1 as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      final core::int* #t11 = #t10 as{TypeError} core::int*;
+      #t9.{core::Set::add}{Invariant}(#t11){(core::int*) →* core::bool*};
+    }
+    for (final dynamic #t12 in dynamicSet2 as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      final core::int* #t13 = #t12 as{TypeError} core::int*;
+      #t9.{core::Set::add}{Invariant}(#t13){(core::int*) →* core::bool*};
+    }
+    #t9.{core::Set::addAll}{Invariant}(iterableIntSet){(core::Iterable<core::int*>*) →* void};
+    for (final dynamic #t14 in iterableNumSet1) {
+      final core::int* #t15 = #t14 as{TypeError} core::int*;
+      #t9.{core::Set::add}{Invariant}(#t15){(core::int*) →* core::bool*};
+    }
+    for (final dynamic #t16 in iterableNumSet2) {
+      final core::int* #t17 = #t16 as{TypeError} core::int*;
+      #t9.{core::Set::add}{Invariant}(#t17){(core::int*) →* core::bool*};
+    }
+    #t9.{core::Set::addAll}{Invariant}(intSet){(core::Iterable<core::int*>*) →* void};
+    for (final dynamic #t18 in numSet1) {
+      final core::int* #t19 = #t18 as{TypeError} core::int*;
+      #t9.{core::Set::add}{Invariant}(#t19){(core::int*) →* core::bool*};
+    }
+    for (final dynamic #t20 in numSet2) {
+      final core::int* #t21 = #t20 as{TypeError} core::int*;
+      #t9.{core::Set::add}{Invariant}(#t21){(core::int*) →* core::bool*};
+    }
+  } =>#t9;
+  self::expect(core::List::generate<core::int*>(24, (core::int* i) → core::int* => i).{core::Iterable::toSet}(){() →* core::Set<core::int*>*}, set1);
+  core::Set<core::num*>* set2 = block {
+    final core::Set<core::num*>* #t22 = col::LinkedHashSet::•<core::num*>();
+    for (final dynamic #t23 in dynamicSet1 as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      final core::num* #t24 = #t23 as{TypeError} core::num*;
+      #t22.{core::Set::add}{Invariant}(#t24){(core::num*) →* core::bool*};
+    }
+    for (final dynamic #t25 in dynamicSet2 as{TypeError,ForDynamic} core::Iterable<dynamic>*) {
+      final core::num* #t26 = #t25 as{TypeError} core::num*;
+      #t22.{core::Set::add}{Invariant}(#t26){(core::num*) →* core::bool*};
+    }
+    #t22.{core::Set::addAll}{Invariant}(iterableIntSet){(core::Iterable<core::num*>*) →* void};
+    #t22.{core::Set::addAll}{Invariant}(iterableNumSet1){(core::Iterable<core::num*>*) →* void};
+    #t22.{core::Set::addAll}{Invariant}(iterableNumSet2){(core::Iterable<core::num*>*) →* void};
+    #t22.{core::Set::addAll}{Invariant}(intSet){(core::Iterable<core::num*>*) →* void};
+    #t22.{core::Set::addAll}{Invariant}(numSet1){(core::Iterable<core::num*>*) →* void};
+    #t22.{core::Set::addAll}{Invariant}(numSet2){(core::Iterable<core::num*>*) →* void};
+  } =>#t22;
+  self::expect(core::List::generate<core::num*>(24, (core::int* i) → core::int* => i).{core::Iterable::toSet}(){() →* core::Set<core::num*>*}, set2);
+  core::Set<core::int*>* set3 = block {
+    final core::Set<core::int*>* #t27 = col::LinkedHashSet::•<core::int*>();
+    final core::Iterable<dynamic>* #t28 = dynamicSet1 as{TypeError,ForDynamic} core::Iterable<dynamic>*;
+    if(!(#t28 == null))
+      for (final dynamic #t29 in #t28) {
+        final core::int* #t30 = #t29 as{TypeError} core::int*;
+        #t27.{core::Set::add}{Invariant}(#t30){(core::int*) →* core::bool*};
+      }
+    final core::Iterable<dynamic>* #t31 = dynamicSet2 as{TypeError,ForDynamic} core::Iterable<dynamic>*;
+    if(!(#t31 == null))
+      for (final dynamic #t32 in #t31) {
+        final core::int* #t33 = #t32 as{TypeError} core::int*;
+        #t27.{core::Set::add}{Invariant}(#t33){(core::int*) →* core::bool*};
+      }
+    final core::Iterable<core::int*>* #t34 = iterableIntSet;
+    if(!(#t34 == null))
+      #t27.{core::Set::addAll}{Invariant}(#t34){(core::Iterable<core::int*>*) →* void};
+    final core::Iterable<dynamic>* #t35 = iterableNumSet1;
+    if(!(#t35 == null))
+      for (final dynamic #t36 in #t35) {
+        final core::int* #t37 = #t36 as{TypeError} core::int*;
+        #t27.{core::Set::add}{Invariant}(#t37){(core::int*) →* core::bool*};
+      }
+    final core::Iterable<dynamic>* #t38 = iterableNumSet2;
+    if(!(#t38 == null))
+      for (final dynamic #t39 in #t38) {
+        final core::int* #t40 = #t39 as{TypeError} core::int*;
+        #t27.{core::Set::add}{Invariant}(#t40){(core::int*) →* core::bool*};
+      }
+    final core::Iterable<core::int*>* #t41 = intSet;
+    if(!(#t41 == null))
+      #t27.{core::Set::addAll}{Invariant}(#t41){(core::Iterable<core::int*>*) →* void};
+    final core::Iterable<dynamic>* #t42 = numSet1;
+    if(!(#t42 == null))
+      for (final dynamic #t43 in #t42) {
+        final core::int* #t44 = #t43 as{TypeError} core::int*;
+        #t27.{core::Set::add}{Invariant}(#t44){(core::int*) →* core::bool*};
+      }
+    final core::Iterable<dynamic>* #t45 = numSet2;
+    if(!(#t45 == null))
+      for (final dynamic #t46 in #t45) {
+        final core::int* #t47 = #t46 as{TypeError} core::int*;
+        #t27.{core::Set::add}{Invariant}(#t47){(core::int*) →* core::bool*};
+      }
+  } =>#t27;
+  self::expect(core::List::generate<core::int*>(24, (core::int* i) → core::int* => i).{core::Iterable::toSet}(){() →* core::Set<core::int*>*}, set3);
+  core::Set<core::num*>* set4 = block {
+    final core::Set<core::num*>* #t48 = col::LinkedHashSet::•<core::num*>();
+    final core::Iterable<dynamic>* #t49 = dynamicSet1 as{TypeError,ForDynamic} core::Iterable<dynamic>*;
+    if(!(#t49 == null))
+      for (final dynamic #t50 in #t49) {
+        final core::num* #t51 = #t50 as{TypeError} core::num*;
+        #t48.{core::Set::add}{Invariant}(#t51){(core::num*) →* core::bool*};
+      }
+    final core::Iterable<dynamic>* #t52 = dynamicSet2 as{TypeError,ForDynamic} core::Iterable<dynamic>*;
+    if(!(#t52 == null))
+      for (final dynamic #t53 in #t52) {
+        final core::num* #t54 = #t53 as{TypeError} core::num*;
+        #t48.{core::Set::add}{Invariant}(#t54){(core::num*) →* core::bool*};
+      }
+    final core::Iterable<core::num*>* #t55 = iterableIntSet;
+    if(!(#t55 == null))
+      #t48.{core::Set::addAll}{Invariant}(#t55){(core::Iterable<core::num*>*) →* void};
+    final core::Iterable<core::num*>* #t56 = iterableNumSet1;
+    if(!(#t56 == null))
+      #t48.{core::Set::addAll}{Invariant}(#t56){(core::Iterable<core::num*>*) →* void};
+    final core::Iterable<core::num*>* #t57 = iterableNumSet2;
+    if(!(#t57 == null))
+      #t48.{core::Set::addAll}{Invariant}(#t57){(core::Iterable<core::num*>*) →* void};
+    final core::Iterable<core::num*>* #t58 = intSet;
+    if(!(#t58 == null))
+      #t48.{core::Set::addAll}{Invariant}(#t58){(core::Iterable<core::num*>*) →* void};
+    final core::Iterable<core::num*>* #t59 = numSet1;
+    if(!(#t59 == null))
+      #t48.{core::Set::addAll}{Invariant}(#t59){(core::Iterable<core::num*>*) →* void};
+    final core::Iterable<core::num*>* #t60 = numSet2;
+    if(!(#t60 == null))
+      #t48.{core::Set::addAll}{Invariant}(#t60){(core::Iterable<core::num*>*) →* void};
+  } =>#t48;
+  self::expect(core::List::generate<core::num*>(24, (core::int* i) → core::int* => i).{core::Iterable::toSet}(){() →* core::Set<core::num*>*}, set4);
+}
+static method main() → dynamic {
+  self::useAddAll();
+}
+static method expect(core::Set<dynamic>* set1, core::Set<dynamic>* set2) → void {
+  if(!(set1.{_in::EfficientLengthIterable::length}{core::int*} =={core::num::==}{(core::Object*) →* core::bool*} set2.{_in::EfficientLengthIterable::length}{core::int*})) {
+    throw "Unexpected length. Expected ${set1.{_in::EfficientLengthIterable::length}{core::int*}}, actual ${set2.{_in::EfficientLengthIterable::length}{core::int*}}.";
+  }
+  for (dynamic element in set1) {
+    if(!set2.{core::Set::contains}(element){(core::Object*) →* core::bool*}) {
+      throw "Element ${element} not found. Expected ${set1}, actual ${set2}.";
+    }
+  }
+}
diff --git a/pkg/front_end/testcases/unified_collections/set_add_all_nnbd.dart.weak.modular.expect b/pkg/front_end/testcases/unified_collections/set_add_all_nnbd.dart.weak.modular.expect
new file mode 100644
index 0000000..4037509
--- /dev/null
+++ b/pkg/front_end/testcases/unified_collections/set_add_all_nnbd.dart.weak.modular.expect
@@ -0,0 +1,176 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "dart:collection" as col;
+import "dart:_internal" as _in;
+
+static method useAddAll() → void {
+  dynamic dynamicSet1 = block {
+    final core::Set<core::int> #t1 = col::LinkedHashSet::•<core::int>();
+    #t1.{core::Set::add}{Invariant}(0){(core::int) → core::bool};
+    #t1.{core::Set::add}{Invariant}(1){(core::int) → core::bool};
+    #t1.{core::Set::add}{Invariant}(2){(core::int) → core::bool};
+  } =>#t1;
+  dynamic dynamicSet2 = block {
+    final core::Set<core::num> #t2 = col::LinkedHashSet::•<core::num>();
+    #t2.{core::Set::add}{Invariant}(3){(core::num) → core::bool};
+    #t2.{core::Set::add}{Invariant}(4){(core::num) → core::bool};
+    #t2.{core::Set::add}{Invariant}(5){(core::num) → core::bool};
+  } =>#t2;
+  dynamic dynamicSet3 = block {
+    final core::Set<core::int?> #t3 = col::LinkedHashSet::•<core::int?>();
+    #t3.{core::Set::add}{Invariant}(6){(core::int?) → core::bool};
+    #t3.{core::Set::add}{Invariant}(7){(core::int?) → core::bool};
+    #t3.{core::Set::add}{Invariant}(8){(core::int?) → core::bool};
+  } =>#t3;
+  core::Iterable<core::int> iterableIntSet = block {
+    final core::Set<core::int> #t4 = col::LinkedHashSet::•<core::int>();
+    #t4.{core::Set::add}{Invariant}(9){(core::int) → core::bool};
+    #t4.{core::Set::add}{Invariant}(10){(core::int) → core::bool};
+    #t4.{core::Set::add}{Invariant}(11){(core::int) → core::bool};
+  } =>#t4;
+  core::Set<core::int> intSet = block {
+    final core::Set<core::int> #t5 = col::LinkedHashSet::•<core::int>();
+    #t5.{core::Set::add}{Invariant}(12){(core::int) → core::bool};
+    #t5.{core::Set::add}{Invariant}(13){(core::int) → core::bool};
+    #t5.{core::Set::add}{Invariant}(14){(core::int) → core::bool};
+  } =>#t5;
+  core::Set<core::int> set1 = block {
+    final core::Set<core::int> #t6 = col::LinkedHashSet::•<core::int>();
+    for (final dynamic #t7 in dynamicSet1 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>) {
+      final core::int #t8 = #t7 as{TypeError,ForNonNullableByDefault} core::int;
+      #t6.{core::Set::add}{Invariant}(#t8){(core::int) → core::bool};
+    }
+    for (final dynamic #t9 in dynamicSet2 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>) {
+      final core::int #t10 = #t9 as{TypeError,ForNonNullableByDefault} core::int;
+      #t6.{core::Set::add}{Invariant}(#t10){(core::int) → core::bool};
+    }
+    for (final dynamic #t11 in dynamicSet3 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>) {
+      final core::int #t12 = #t11 as{TypeError,ForNonNullableByDefault} core::int;
+      #t6.{core::Set::add}{Invariant}(#t12){(core::int) → core::bool};
+    }
+    #t6.{core::Set::addAll}{Invariant}(iterableIntSet){(core::Iterable<core::int>) → void};
+    #t6.{core::Set::addAll}{Invariant}(intSet){(core::Iterable<core::int>) → void};
+  } =>#t6;
+  self::expect(core::List::generate<core::int>(15, (core::int i) → core::int => i).{core::Iterable::toSet}(){() → core::Set<core::int>}, set1);
+  core::Set<core::num> set2 = block {
+    final core::Set<core::num> #t13 = col::LinkedHashSet::•<core::num>();
+    for (final dynamic #t14 in dynamicSet1 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>) {
+      final core::num #t15 = #t14 as{TypeError,ForNonNullableByDefault} core::num;
+      #t13.{core::Set::add}{Invariant}(#t15){(core::num) → core::bool};
+    }
+    for (final dynamic #t16 in dynamicSet2 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>) {
+      final core::num #t17 = #t16 as{TypeError,ForNonNullableByDefault} core::num;
+      #t13.{core::Set::add}{Invariant}(#t17){(core::num) → core::bool};
+    }
+    for (final dynamic #t18 in dynamicSet3 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>) {
+      final core::num #t19 = #t18 as{TypeError,ForNonNullableByDefault} core::num;
+      #t13.{core::Set::add}{Invariant}(#t19){(core::num) → core::bool};
+    }
+    #t13.{core::Set::addAll}{Invariant}(iterableIntSet){(core::Iterable<core::num>) → void};
+    #t13.{core::Set::addAll}{Invariant}(intSet){(core::Iterable<core::num>) → void};
+  } =>#t13;
+  self::expect(core::List::generate<core::num>(15, (core::int i) → core::int => i).{core::Iterable::toSet}(){() → core::Set<core::num>}, set2);
+}
+static method useAddAllNullable() → void {
+  dynamic dynamicSet1 = block {
+    final core::Set<core::int> #t20 = col::LinkedHashSet::•<core::int>();
+    #t20.{core::Set::add}{Invariant}(0){(core::int) → core::bool};
+    #t20.{core::Set::add}{Invariant}(1){(core::int) → core::bool};
+    #t20.{core::Set::add}{Invariant}(2){(core::int) → core::bool};
+  } =>#t20;
+  dynamic dynamicSet2 = block {
+    final core::Set<core::num> #t21 = col::LinkedHashSet::•<core::num>();
+    #t21.{core::Set::add}{Invariant}(3){(core::num) → core::bool};
+    #t21.{core::Set::add}{Invariant}(4){(core::num) → core::bool};
+    #t21.{core::Set::add}{Invariant}(5){(core::num) → core::bool};
+  } =>#t21;
+  dynamic dynamicSet3 = block {
+    final core::Set<core::int?> #t22 = col::LinkedHashSet::•<core::int?>();
+    #t22.{core::Set::add}{Invariant}(6){(core::int?) → core::bool};
+    #t22.{core::Set::add}{Invariant}(7){(core::int?) → core::bool};
+    #t22.{core::Set::add}{Invariant}(8){(core::int?) → core::bool};
+  } =>#t22;
+  core::Iterable<core::int>? iterableIntSet = true ?{core::Set<core::int>?} block {
+    final core::Set<core::int> #t23 = col::LinkedHashSet::•<core::int>();
+    #t23.{core::Set::add}{Invariant}(9){(core::int) → core::bool};
+    #t23.{core::Set::add}{Invariant}(10){(core::int) → core::bool};
+    #t23.{core::Set::add}{Invariant}(11){(core::int) → core::bool};
+  } =>#t23 : null;
+  core::Set<core::int>? intSet = true ?{core::Set<core::int>?} block {
+    final core::Set<core::int> #t24 = col::LinkedHashSet::•<core::int>();
+    #t24.{core::Set::add}{Invariant}(12){(core::int) → core::bool};
+    #t24.{core::Set::add}{Invariant}(13){(core::int) → core::bool};
+    #t24.{core::Set::add}{Invariant}(14){(core::int) → core::bool};
+  } =>#t24 : null;
+  core::Set<core::int> set1 = block {
+    final core::Set<core::int> #t25 = col::LinkedHashSet::•<core::int>();
+    final core::Iterable<dynamic>? #t26 = dynamicSet1 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>?;
+    if(!(#t26 == null))
+      for (final dynamic #t27 in #t26{core::Iterable<dynamic>}) {
+        final core::int #t28 = #t27 as{TypeError,ForNonNullableByDefault} core::int;
+        #t25.{core::Set::add}{Invariant}(#t28){(core::int) → core::bool};
+      }
+    final core::Iterable<dynamic>? #t29 = dynamicSet2 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>?;
+    if(!(#t29 == null))
+      for (final dynamic #t30 in #t29{core::Iterable<dynamic>}) {
+        final core::int #t31 = #t30 as{TypeError,ForNonNullableByDefault} core::int;
+        #t25.{core::Set::add}{Invariant}(#t31){(core::int) → core::bool};
+      }
+    final core::Iterable<dynamic>? #t32 = dynamicSet3 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>?;
+    if(!(#t32 == null))
+      for (final dynamic #t33 in #t32{core::Iterable<dynamic>}) {
+        final core::int #t34 = #t33 as{TypeError,ForNonNullableByDefault} core::int;
+        #t25.{core::Set::add}{Invariant}(#t34){(core::int) → core::bool};
+      }
+    final core::Iterable<core::int>? #t35 = iterableIntSet;
+    if(!(#t35 == null))
+      #t25.{core::Set::addAll}{Invariant}(#t35{core::Iterable<core::int>}){(core::Iterable<core::int>) → void};
+    final core::Iterable<core::int>? #t36 = intSet;
+    if(!(#t36 == null))
+      #t25.{core::Set::addAll}{Invariant}(#t36{core::Iterable<core::int>}){(core::Iterable<core::int>) → void};
+  } =>#t25;
+  self::expect(core::List::generate<core::int>(15, (core::int i) → core::int => i).{core::Iterable::toSet}(){() → core::Set<core::int>}, set1);
+  core::Set<core::num> set2 = block {
+    final core::Set<core::num> #t37 = col::LinkedHashSet::•<core::num>();
+    final core::Iterable<dynamic>? #t38 = dynamicSet1 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>?;
+    if(!(#t38 == null))
+      for (final dynamic #t39 in #t38{core::Iterable<dynamic>}) {
+        final core::num #t40 = #t39 as{TypeError,ForNonNullableByDefault} core::num;
+        #t37.{core::Set::add}{Invariant}(#t40){(core::num) → core::bool};
+      }
+    final core::Iterable<dynamic>? #t41 = dynamicSet2 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>?;
+    if(!(#t41 == null))
+      for (final dynamic #t42 in #t41{core::Iterable<dynamic>}) {
+        final core::num #t43 = #t42 as{TypeError,ForNonNullableByDefault} core::num;
+        #t37.{core::Set::add}{Invariant}(#t43){(core::num) → core::bool};
+      }
+    final core::Iterable<dynamic>? #t44 = dynamicSet3 as{TypeError,ForDynamic,ForNonNullableByDefault} core::Iterable<dynamic>?;
+    if(!(#t44 == null))
+      for (final dynamic #t45 in #t44{core::Iterable<dynamic>}) {
+        final core::num #t46 = #t45 as{TypeError,ForNonNullableByDefault} core::num;
+        #t37.{core::Set::add}{Invariant}(#t46){(core::num) → core::bool};
+      }
+    final core::Iterable<core::num>? #t47 = iterableIntSet;
+    if(!(#t47 == null))
+      #t37.{core::Set::addAll}{Invariant}(#t47{core::Iterable<core::num>}){(core::Iterable<core::num>) → void};
+    final core::Iterable<core::num>? #t48 = intSet;
+    if(!(#t48 == null))
+      #t37.{core::Set::addAll}{Invariant}(#t48{core::Iterable<core::num>}){(core::Iterable<core::num>) → void};
+  } =>#t37;
+  self::expect(core::List::generate<core::num>(15, (core::int i) → core::int => i).{core::Iterable::toSet}(){() → core::Set<core::num>}, set2);
+}
+static method main() → dynamic {
+  self::useAddAll();
+  self::useAddAllNullable();
+}
+static method expect(core::Set<dynamic> set1, core::Set<dynamic> set2) → void {
+  if(!(set1.{_in::EfficientLengthIterable::length}{core::int} =={core::num::==}{(core::Object) → core::bool} set2.{_in::EfficientLengthIterable::length}{core::int})) {
+    throw "Unexpected length. Expected ${set1.{_in::EfficientLengthIterable::length}{core::int}}, actual ${set2.{_in::EfficientLengthIterable::length}{core::int}}.";
+  }
+  for (dynamic element in set1) {
+    if(!set2.{core::Set::contains}(element){(core::Object?) → core::bool}) {
+      throw "Element ${element} not found. Expected ${set1}, actual ${set2}.";
+    }
+  }
+}
diff --git a/pkg/front_end/testcases/unified_collections/string_concatenation.dart.weak.modular.expect b/pkg/front_end/testcases/unified_collections/string_concatenation.dart.weak.modular.expect
new file mode 100644
index 0000000..2263773
--- /dev/null
+++ b/pkg/front_end/testcases/unified_collections/string_concatenation.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+static method main() → dynamic {
+  core::bool* b = false;
+  block {
+    final core::List<core::String*>* #t1 = <core::String*>["ab"];
+    if(b)
+      #t1.{core::List::add}{Invariant}("cd"){(core::String*) →* void};
+  } =>#t1;
+}
diff --git a/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.weak.modular.expect b/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.weak.modular.expect
new file mode 100644
index 0000000..f81b865
--- /dev/null
+++ b/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.weak.modular.expect
@@ -0,0 +1,142 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/value_class/copy_with_call_sites.dart:20:21: Error: The parameter 'bar' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   Foo copyWith({int bar, int bar2}) {
+//                     ^^^
+//
+// pkg/front_end/testcases/value_class/copy_with_call_sites.dart:20:30: Error: The parameter 'bar2' can't have a value of 'null' because of its type 'int', but the implicit default value is 'null'.
+// Try adding either an explicit non-'null' default value or the 'required' modifier.
+//   Foo copyWith({int bar, int bar2}) {
+//                              ^^^^
+//
+// pkg/front_end/testcases/value_class/copy_with_call_sites.dart:21:15: Error: Too many positional arguments: 0 allowed, but 2 found.
+// Try removing the extra positional arguments.
+//     return Foo(bar, bar2);
+//               ^
+// pkg/front_end/testcases/value_class/copy_with_call_sites.dart:19:3: Context: Found this candidate, but the arguments don't match.
+//   Foo({this.bar, this.bar2});
+//   ^^^
+//
+// pkg/front_end/testcases/value_class/copy_with_call_sites.dart:29:20: Error: No named parameter with the name 'numberOfWhiskers'.
+//  Cat cat = new Cat(numberOfWhiskers: 20, numberOfLegs: 4);
+//                    ^^^^^^^^^^^^^^^^
+// pkg/front_end/testcases/value_class/copy_with_call_sites.dart:13:7: Context: The class 'Cat' has a constructor that takes no arguments.
+// class Cat extends Animal {
+//       ^
+//
+// pkg/front_end/testcases/value_class/copy_with_call_sites.dart:35:29: Error: The method 'copyWith' isn't defined for the class 'Object'.
+//  - 'Object' is from 'dart:core'.
+// Try correcting the name to the name of an existing method, or defining a method named 'copyWith'.
+//  Cat cat4 = (cat as Object).copyWith(numberOfWhiskers: 4);
+//                             ^^^^^^^^
+//
+// pkg/front_end/testcases/value_class/copy_with_call_sites.dart:43:10: Error: Non-nullable variable 'a' must be assigned before it can be used.
+//  A a2 = (a as dynamic).copyWith(x: 42, y: 42) as A;
+//          ^
+//
+// pkg/front_end/testcases/value_class/copy_with_call_sites.dart:14:14: Error: Final field 'numberOfWhiskers' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int? numberOfWhiskers;
+//              ^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "value_class_support_lib.dart" as val;
+
+import "org-dartlang-testcase:///value_class_support_lib.dart";
+
+class Animal extends core::Object {
+  final field core::int? numberOfLegs;
+  constructor •({required core::int? numberOfLegs = #C1}) → self::Animal
+    : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
+    ;
+}
+class Cat extends self::Animal {
+  final field core::int? numberOfWhiskers = null;
+  synthetic constructor •({required core::int? numberOfWhiskers, core::int? numberOfLegs}) → self::Cat
+    : self::Cat::numberOfWhiskers = numberOfWhiskers, super self::Animal::•(numberOfLegs)
+    ;
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
+    return other is self::Cat && this.{self::Animal::numberOfLegs}{core::int?} =={core::num::==}{(core::Object) → core::bool} other{self::Cat}.{self::Animal::numberOfLegs}{core::int?} && this.{self::Cat::numberOfWhiskers}{core::int?} =={core::num::==}{(core::Object) → core::bool} other{self::Cat}.{self::Cat::numberOfWhiskers}{core::int?};
+  get /*isLegacy*/ hashCode() → core::int
+    return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///copy_with_call_sites.dartCat".{core::String::hashCode}{core::int}, this.{self::Animal::numberOfLegs}{core::int?}.{core::num::hashCode}{core::int}), this.{self::Cat::numberOfWhiskers}{core::int?}.{core::num::hashCode}{core::int}));
+  method /*isLegacy*/ toString() → core::String
+    return "Cat(numberOfLegs: ${this.{self::Animal::numberOfLegs}{core::int?}.{core::int::toString}(){() → core::String}}, numberOfWhiskers: ${this.{self::Cat::numberOfWhiskers}{core::int?}.{core::int::toString}(){() → core::String}})";
+  method /*isLegacy*/ copyWith({core::int? numberOfLegs, core::int? numberOfWhiskers}) → dynamic
+    return new self::Cat::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
+}
+class Foo extends core::Object {
+  field core::int? bar;
+  field core::int? bar2;
+  constructor •({core::int? bar = #C1, core::int? bar2 = #C1}) → self::Foo
+    : self::Foo::bar = bar, self::Foo::bar2 = bar2, super core::Object::•()
+    ;
+  method copyWith({core::int bar = #C1, core::int bar2 = #C1}) → self::Foo {
+    return invalid-expression "pkg/front_end/testcases/value_class/copy_with_call_sites.dart:21:15: Error: Too many positional arguments: 0 allowed, but 2 found.
+Try removing the extra positional arguments.
+    return Foo(bar, bar2);
+              ^";
+  }
+}
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
+    return other is self::A;
+  get /*isLegacy*/ hashCode() → core::int
+    return val::JenkinsSmiHash::finish("org-dartlang-testcase:///copy_with_call_sites.dartA".{core::String::hashCode}{core::int});
+  method /*isLegacy*/ toString() → core::String
+    return "A()";
+  method /*isLegacy*/ copyWith() → dynamic
+    return new self::A::•();
+}
+static method main() → dynamic {
+  self::Cat cat = invalid-expression "pkg/front_end/testcases/value_class/copy_with_call_sites.dart:29:20: Error: No named parameter with the name 'numberOfWhiskers'.
+ Cat cat = new Cat(numberOfWhiskers: 20, numberOfLegs: 4);
+                   ^^^^^^^^^^^^^^^^";
+  self::Cat cat2 = (cat as{ForNonNullableByDefault} dynamic){dynamic}.copyWith(numberOfWhiskers: 4) as{ForNonNullableByDefault} self::Cat;
+  self::Cat cat3 = (((cat as{ForNonNullableByDefault} dynamic){dynamic}.copyWith(numberOfWhiskers: 4) as{ForNonNullableByDefault} self::Cat) as{ForNonNullableByDefault} dynamic){dynamic}.copyWith(numberOfLegs: 3) as{ForNonNullableByDefault} self::Cat;
+  self::Cat cat4 = invalid-expression "pkg/front_end/testcases/value_class/copy_with_call_sites.dart:35:29: Error: The method 'copyWith' isn't defined for the class 'Object'.
+ - 'Object' is from 'dart:core'.
+Try correcting the name to the name of an existing method, or defining a method named 'copyWith'.
+ Cat cat4 = (cat as Object).copyWith(numberOfWhiskers: 4);
+                            ^^^^^^^^" in (cat as{ForNonNullableByDefault} core::Object){<unresolved>}.copyWith(numberOfWhiskers: 4) as{TypeError,ForDynamic,ForNonNullableByDefault} self::Cat;
+  self::Cat cat5 = (cat as{ForNonNullableByDefault} dynamic){dynamic}.copyWith() as{ForNonNullableByDefault} self::Cat;
+  self::Cat cat6 = (cat as{ForNonNullableByDefault} dynamic){dynamic}.copyWith(numberOfWhiskers: 4, numberOfHorns: 5) as{ForNonNullableByDefault} self::Cat;
+  self::A a;
+  self::A a2 = (invalid-expression "pkg/front_end/testcases/value_class/copy_with_call_sites.dart:43:10: Error: Non-nullable variable 'a' must be assigned before it can be used.
+ A a2 = (a as dynamic).copyWith(x: 42, y: 42) as A;
+         ^" in a as{ForNonNullableByDefault} dynamic){dynamic}.copyWith(x: 42, y: 42) as{ForNonNullableByDefault} self::A;
+  self::Foo foo = new self::Foo::•(bar: 4, bar2: 5);
+  self::Foo foo2 = (foo as{ForNonNullableByDefault} dynamic){dynamic}.copyWith(bar: 4) as{ForNonNullableByDefault} self::Foo;
+}
+
+library /*isNonNullableByDefault*/;
+import self as val;
+import "dart:core" as core;
+
+class JenkinsSmiHash extends core::Object {
+  synthetic constructor •() → val::JenkinsSmiHash
+    : super core::Object::•()
+    ;
+  static method combine(core::int hash, core::int value) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(value){(core::num) → core::int}){(core::int) → core::int};
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(524287.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(10){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    return hash.{core::int::^}(hash.{core::int::>>}(6){(core::int) → core::int}){(core::int) → core::int};
+  }
+  static method finish(core::int hash) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(67108863.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(3){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    hash = hash.{core::int::^}(hash.{core::int::>>}(11){(core::int) → core::int}){(core::int) → core::int};
+    return 536870911.{core::int::&}(hash.{core::num::+}(16383.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(15){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+  }
+}
+static const field core::String valueClass = #C2;
+
+constants  {
+  #C1 = null
+  #C2 = "valueClass"
+}
diff --git a/pkg/front_end/testcases/value_class/empty.dart.weak.modular.expect b/pkg/front_end/testcases/value_class/empty.dart.weak.modular.expect
new file mode 100644
index 0000000..d243d4d
--- /dev/null
+++ b/pkg/front_end/testcases/value_class/empty.dart.weak.modular.expect
@@ -0,0 +1,46 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "value_class_support_lib.dart" as val;
+
+import "org-dartlang-testcase:///value_class_support_lib.dart";
+
+class EmptyClass extends core::Object {
+  synthetic constructor •() → self::EmptyClass
+    : super core::Object::•()
+    ;
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
+    return other is self::EmptyClass;
+  get /*isLegacy*/ hashCode() → core::int
+    return val::JenkinsSmiHash::finish("org-dartlang-testcase:///empty.dartEmptyClass".{core::String::hashCode}{core::int});
+  method /*isLegacy*/ toString() → core::String
+    return "EmptyClass()";
+  method /*isLegacy*/ copyWith() → dynamic
+    return new self::EmptyClass::•();
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as val;
+import "dart:core" as core;
+
+class JenkinsSmiHash extends core::Object {
+  synthetic constructor •() → val::JenkinsSmiHash
+    : super core::Object::•()
+    ;
+  static method combine(core::int hash, core::int value) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(value){(core::num) → core::int}){(core::int) → core::int};
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(524287.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(10){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    return hash.{core::int::^}(hash.{core::int::>>}(6){(core::int) → core::int}){(core::int) → core::int};
+  }
+  static method finish(core::int hash) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(67108863.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(3){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    hash = hash.{core::int::^}(hash.{core::int::>>}(11){(core::int) → core::int}){(core::int) → core::int};
+    return 536870911.{core::int::&}(hash.{core::num::+}(16383.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(15){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+  }
+}
+static const field core::String valueClass = #C1;
+
+constants  {
+  #C1 = "valueClass"
+}
diff --git a/pkg/front_end/testcases/value_class/explicit_mixin.dart.weak.modular.expect b/pkg/front_end/testcases/value_class/explicit_mixin.dart.weak.modular.expect
new file mode 100644
index 0000000..0509836
--- /dev/null
+++ b/pkg/front_end/testcases/value_class/explicit_mixin.dart.weak.modular.expect
@@ -0,0 +1,79 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "value_class_support_lib.dart" as val;
+
+import "org-dartlang-testcase:///value_class_support_lib.dart";
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
+    return other is self::A;
+  get /*isLegacy*/ hashCode() → core::int
+    return val::JenkinsSmiHash::finish("org-dartlang-testcase:///explicit_mixin.dartA".{core::String::hashCode}{core::int});
+  method /*isLegacy*/ toString() → core::String
+    return "A()";
+  method /*isLegacy*/ copyWith() → dynamic
+    return new self::A::•();
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+}
+class C extends core::Object {
+  synthetic constructor •() → self::C
+    : super core::Object::•()
+    ;
+}
+class D = self::A with self::B {
+  synthetic constructor •() → self::D
+    : super self::A::•()
+    ;
+}
+class E = self::B with self::A {
+  synthetic constructor •() → self::E
+    : super self::B::•()
+    ;
+}
+class F = self::B with self::C {
+  synthetic constructor •() → self::F
+    : super self::B::•()
+    ;
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
+    return other is self::F;
+  get /*isLegacy*/ hashCode() → core::int
+    return val::JenkinsSmiHash::finish("org-dartlang-testcase:///explicit_mixin.dartF".{core::String::hashCode}{core::int});
+  method /*isLegacy*/ toString() → core::String
+    return "F()";
+  method /*isLegacy*/ copyWith() → dynamic
+    return new self::F::•();
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as val;
+import "dart:core" as core;
+
+class JenkinsSmiHash extends core::Object {
+  synthetic constructor •() → val::JenkinsSmiHash
+    : super core::Object::•()
+    ;
+  static method combine(core::int hash, core::int value) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(value){(core::num) → core::int}){(core::int) → core::int};
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(524287.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(10){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    return hash.{core::int::^}(hash.{core::int::>>}(6){(core::int) → core::int}){(core::int) → core::int};
+  }
+  static method finish(core::int hash) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(67108863.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(3){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    hash = hash.{core::int::^}(hash.{core::int::>>}(11){(core::int) → core::int}){(core::int) → core::int};
+    return 536870911.{core::int::&}(hash.{core::num::+}(16383.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(15){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+  }
+}
+static const field core::String valueClass = #C1;
+
+constants  {
+  #C1 = "valueClass"
+}
diff --git a/pkg/front_end/testcases/value_class/non_final_field_error.dart.weak.modular.expect b/pkg/front_end/testcases/value_class/non_final_field_error.dart.weak.modular.expect
new file mode 100644
index 0000000..a3eef16
--- /dev/null
+++ b/pkg/front_end/testcases/value_class/non_final_field_error.dart.weak.modular.expect
@@ -0,0 +1,54 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/value_class/non_final_field_error.dart:9:7: Error: Field 'numberOfLegs' should be initialized because its type 'int' doesn't allow null.
+//   int numberOfLegs;
+//       ^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "value_class_support_lib.dart" as val;
+
+import "org-dartlang-testcase:///value_class_support_lib.dart";
+
+class Animal extends core::Object {
+  field core::int numberOfLegs = null;
+  synthetic constructor •({required core::int numberOfLegs}) → self::Animal
+    : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
+    ;
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
+    return other is self::Animal && this.{self::Animal::numberOfLegs}{core::int} =={core::num::==}{(core::Object) → core::bool} other{self::Animal}.{self::Animal::numberOfLegs}{core::int};
+  get /*isLegacy*/ hashCode() → core::int
+    return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///non_final_field_error.dartAnimal".{core::String::hashCode}{core::int}, this.{self::Animal::numberOfLegs}{core::int}.{core::num::hashCode}{core::int}));
+  method /*isLegacy*/ toString() → core::String
+    return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}{core::int}.{core::int::toString}(){() → core::String}})";
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
+    return new self::Animal::•(numberOfLegs: numberOfLegs);
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as val;
+import "dart:core" as core;
+
+class JenkinsSmiHash extends core::Object {
+  synthetic constructor •() → val::JenkinsSmiHash
+    : super core::Object::•()
+    ;
+  static method combine(core::int hash, core::int value) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(value){(core::num) → core::int}){(core::int) → core::int};
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(524287.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(10){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    return hash.{core::int::^}(hash.{core::int::>>}(6){(core::int) → core::int}){(core::int) → core::int};
+  }
+  static method finish(core::int hash) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(67108863.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(3){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    hash = hash.{core::int::^}(hash.{core::int::>>}(11){(core::int) → core::int}){(core::int) → core::int};
+    return 536870911.{core::int::&}(hash.{core::num::+}(16383.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(15){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+  }
+}
+static const field core::String valueClass = #C1;
+
+constants  {
+  #C1 = "valueClass"
+}
diff --git a/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.weak.modular.expect b/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.weak.modular.expect
new file mode 100644
index 0000000..eca2eeb
--- /dev/null
+++ b/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.weak.modular.expect
@@ -0,0 +1,60 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/value_class/non_value_extends_value_error.dart:9:13: Error: Final field 'numberOfLegs' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int numberOfLegs;
+//             ^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "value_class_support_lib.dart" as val;
+
+import "org-dartlang-testcase:///value_class_support_lib.dart";
+
+class Animal extends core::Object {
+  final field core::int numberOfLegs = null;
+  synthetic constructor •({required core::int numberOfLegs}) → self::Animal
+    : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
+    ;
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
+    return other is self::Animal && this.{self::Animal::numberOfLegs}{core::int} =={core::num::==}{(core::Object) → core::bool} other{self::Animal}.{self::Animal::numberOfLegs}{core::int};
+  get /*isLegacy*/ hashCode() → core::int
+    return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///non_value_extends_value_error.dartAnimal".{core::String::hashCode}{core::int}, this.{self::Animal::numberOfLegs}{core::int}.{core::num::hashCode}{core::int}));
+  method /*isLegacy*/ toString() → core::String
+    return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}{core::int}.{core::int::toString}(){() → core::String}})";
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
+    return new self::Animal::•(numberOfLegs: numberOfLegs);
+}
+class Cat extends self::Animal {
+  synthetic constructor •() → self::Cat
+    : super self::Animal::•()
+    ;
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as val;
+import "dart:core" as core;
+
+class JenkinsSmiHash extends core::Object {
+  synthetic constructor •() → val::JenkinsSmiHash
+    : super core::Object::•()
+    ;
+  static method combine(core::int hash, core::int value) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(value){(core::num) → core::int}){(core::int) → core::int};
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(524287.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(10){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    return hash.{core::int::^}(hash.{core::int::>>}(6){(core::int) → core::int}){(core::int) → core::int};
+  }
+  static method finish(core::int hash) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(67108863.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(3){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    hash = hash.{core::int::^}(hash.{core::int::>>}(11){(core::int) → core::int}){(core::int) → core::int};
+    return 536870911.{core::int::&}(hash.{core::num::+}(16383.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(15){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+  }
+}
+static const field core::String valueClass = #C1;
+
+constants  {
+  #C1 = "valueClass"
+}
diff --git a/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.weak.modular.expect b/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.weak.modular.expect
new file mode 100644
index 0000000..6759904
--- /dev/null
+++ b/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.weak.modular.expect
@@ -0,0 +1,66 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/value_class/non_value_implements_value_error.dart:9:13: Error: Final field 'numberOfLegs' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int numberOfLegs;
+//             ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/value_class/non_value_implements_value_error.dart:13:13: Error: Final field 'numberOfLegs' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int numberOfLegs;
+//             ^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "value_class_support_lib.dart" as val;
+
+import "org-dartlang-testcase:///value_class_support_lib.dart";
+
+class Animal extends core::Object {
+  final field core::int numberOfLegs = null;
+  synthetic constructor •({required core::int numberOfLegs}) → self::Animal
+    : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
+    ;
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
+    return other is self::Animal && this.{self::Animal::numberOfLegs}{core::int} =={core::num::==}{(core::Object) → core::bool} other{self::Animal}.{self::Animal::numberOfLegs}{core::int};
+  get /*isLegacy*/ hashCode() → core::int
+    return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///non_value_implements_value_error.dartAnimal".{core::String::hashCode}{core::int}, this.{self::Animal::numberOfLegs}{core::int}.{core::num::hashCode}{core::int}));
+  method /*isLegacy*/ toString() → core::String
+    return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}{core::int}.{core::int::toString}(){() → core::String}})";
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
+    return new self::Animal::•(numberOfLegs: numberOfLegs);
+}
+class Cat extends core::Object implements self::Animal {
+  final field core::int numberOfLegs = null;
+  synthetic constructor •() → self::Cat
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as val;
+import "dart:core" as core;
+
+class JenkinsSmiHash extends core::Object {
+  synthetic constructor •() → val::JenkinsSmiHash
+    : super core::Object::•()
+    ;
+  static method combine(core::int hash, core::int value) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(value){(core::num) → core::int}){(core::int) → core::int};
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(524287.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(10){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    return hash.{core::int::^}(hash.{core::int::>>}(6){(core::int) → core::int}){(core::int) → core::int};
+  }
+  static method finish(core::int hash) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(67108863.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(3){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    hash = hash.{core::int::^}(hash.{core::int::>>}(11){(core::int) → core::int}){(core::int) → core::int};
+    return 536870911.{core::int::&}(hash.{core::num::+}(16383.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(15){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+  }
+}
+static const field core::String valueClass = #C1;
+
+constants  {
+  #C1 = "valueClass"
+}
diff --git a/pkg/front_end/testcases/value_class/simple.dart.weak.modular.expect b/pkg/front_end/testcases/value_class/simple.dart.weak.modular.expect
new file mode 100644
index 0000000..0144bcf
--- /dev/null
+++ b/pkg/front_end/testcases/value_class/simple.dart.weak.modular.expect
@@ -0,0 +1,94 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/value_class/simple.dart:13:31: Error: No named parameter with the name 'numberOfLegs'.
+//   Animal firstAnimal = Animal(numberOfLegs: 4);
+//                               ^^^^^^^^^^^^
+// pkg/front_end/testcases/value_class/simple.dart:8:7: Context: The class 'Animal' has a constructor that takes no arguments.
+// class Animal {
+//       ^
+//
+// pkg/front_end/testcases/value_class/simple.dart:14:32: Error: No named parameter with the name 'numberOfLegs'.
+//   Animal secondAnimal = Animal(numberOfLegs: 4);
+//                                ^^^^^^^^^^^^
+// pkg/front_end/testcases/value_class/simple.dart:8:7: Context: The class 'Animal' has a constructor that takes no arguments.
+// class Animal {
+//       ^
+//
+// pkg/front_end/testcases/value_class/simple.dart:15:31: Error: No named parameter with the name 'numberOfLegs'.
+//   Animal thirdAnimal = Animal(numberOfLegs: 3);
+//                               ^^^^^^^^^^^^
+// pkg/front_end/testcases/value_class/simple.dart:8:7: Context: The class 'Animal' has a constructor that takes no arguments.
+// class Animal {
+//       ^
+//
+// pkg/front_end/testcases/value_class/simple.dart:9:13: Error: Final field 'numberOfLegs' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int numberOfLegs;
+//             ^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "value_class_support_lib.dart" as val;
+
+import "org-dartlang-testcase:///value_class_support_lib.dart";
+
+class Animal extends core::Object {
+  final field core::int numberOfLegs = null;
+  synthetic constructor •({required core::int numberOfLegs}) → self::Animal
+    : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
+    ;
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
+    return other is self::Animal && this.{self::Animal::numberOfLegs}{core::int} =={core::num::==}{(core::Object) → core::bool} other{self::Animal}.{self::Animal::numberOfLegs}{core::int};
+  get /*isLegacy*/ hashCode() → core::int
+    return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///simple.dartAnimal".{core::String::hashCode}{core::int}, this.{self::Animal::numberOfLegs}{core::int}.{core::num::hashCode}{core::int}));
+  method /*isLegacy*/ toString() → core::String
+    return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}{core::int}.{core::int::toString}(){() → core::String}})";
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
+    return new self::Animal::•(numberOfLegs: numberOfLegs);
+}
+static method main() → dynamic {
+  self::Animal firstAnimal = invalid-expression "pkg/front_end/testcases/value_class/simple.dart:13:31: Error: No named parameter with the name 'numberOfLegs'.
+  Animal firstAnimal = Animal(numberOfLegs: 4);
+                              ^^^^^^^^^^^^";
+  self::Animal secondAnimal = invalid-expression "pkg/front_end/testcases/value_class/simple.dart:14:32: Error: No named parameter with the name 'numberOfLegs'.
+  Animal secondAnimal = Animal(numberOfLegs: 4);
+                               ^^^^^^^^^^^^";
+  self::Animal thirdAnimal = invalid-expression "pkg/front_end/testcases/value_class/simple.dart:15:31: Error: No named parameter with the name 'numberOfLegs'.
+  Animal thirdAnimal = Animal(numberOfLegs: 3);
+                              ^^^^^^^^^^^^";
+  self::expect(true, firstAnimal =={core::Object::==}{(core::Object) → core::bool} secondAnimal);
+  self::expect(false, firstAnimal =={core::Object::==}{(core::Object) → core::bool} thirdAnimal);
+  self::expect(true, firstAnimal.{core::Object::hashCode}{core::int} =={core::num::==}{(core::Object) → core::bool} secondAnimal.{core::Object::hashCode}{core::int});
+  self::expect(false, firstAnimal.{core::Object::hashCode}{core::int} =={core::num::==}{(core::Object) → core::bool} thirdAnimal.{core::Object::hashCode}{core::int});
+}
+static method expect(core::Object? expected, core::Object? actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected=${expected}, actual=${actual}";
+}
+
+library /*isNonNullableByDefault*/;
+import self as val;
+import "dart:core" as core;
+
+class JenkinsSmiHash extends core::Object {
+  synthetic constructor •() → val::JenkinsSmiHash
+    : super core::Object::•()
+    ;
+  static method combine(core::int hash, core::int value) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(value){(core::num) → core::int}){(core::int) → core::int};
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(524287.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(10){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    return hash.{core::int::^}(hash.{core::int::>>}(6){(core::int) → core::int}){(core::int) → core::int};
+  }
+  static method finish(core::int hash) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(67108863.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(3){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    hash = hash.{core::int::^}(hash.{core::int::>>}(11){(core::int) → core::int}){(core::int) → core::int};
+    return 536870911.{core::int::&}(hash.{core::num::+}(16383.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(15){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+  }
+}
+static const field core::String valueClass = #C1;
+
+constants  {
+  #C1 = "valueClass"
+}
diff --git a/pkg/front_end/testcases/value_class/value_extends_non_value.dart.weak.modular.expect b/pkg/front_end/testcases/value_class/value_extends_non_value.dart.weak.modular.expect
new file mode 100644
index 0000000..955fab2
--- /dev/null
+++ b/pkg/front_end/testcases/value_class/value_extends_non_value.dart.weak.modular.expect
@@ -0,0 +1,101 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/value_class/value_extends_non_value.dart:18:22: Error: No named parameter with the name 'numberOfLegs'.
+//   Cat firstCat = Cat(numberOfLegs: 4, numberOfWhiskers: 10);
+//                      ^^^^^^^^^^^^
+// pkg/front_end/testcases/value_class/value_extends_non_value.dart:13:7: Context: The class 'Cat' has a constructor that takes no arguments.
+// class Cat extends Animal {
+//       ^
+//
+// pkg/front_end/testcases/value_class/value_extends_non_value.dart:19:23: Error: No named parameter with the name 'numberOfLegs'.
+//   Cat secondCat = Cat(numberOfLegs: 4, numberOfWhiskers: 10);
+//                       ^^^^^^^^^^^^
+// pkg/front_end/testcases/value_class/value_extends_non_value.dart:13:7: Context: The class 'Cat' has a constructor that takes no arguments.
+// class Cat extends Animal {
+//       ^
+//
+// pkg/front_end/testcases/value_class/value_extends_non_value.dart:20:22: Error: No named parameter with the name 'numberOfLegs'.
+//   Cat thirdCat = Cat(numberOfLegs: 4, numberOfWhiskers: 0);
+//                      ^^^^^^^^^^^^
+// pkg/front_end/testcases/value_class/value_extends_non_value.dart:13:7: Context: The class 'Cat' has a constructor that takes no arguments.
+// class Cat extends Animal {
+//       ^
+//
+// pkg/front_end/testcases/value_class/value_extends_non_value.dart:14:13: Error: Final field 'numberOfWhiskers' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int numberOfWhiskers;
+//             ^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "value_class_support_lib.dart" as val;
+
+import "org-dartlang-testcase:///value_class_support_lib.dart";
+
+class Animal extends core::Object {
+  final field core::int numberOfLegs;
+  constructor •({required core::int numberOfLegs = #C1}) → self::Animal
+    : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
+    ;
+}
+class Cat extends self::Animal {
+  final field core::int numberOfWhiskers = null;
+  synthetic constructor •({required core::int numberOfWhiskers, core::int numberOfLegs}) → self::Cat
+    : self::Cat::numberOfWhiskers = numberOfWhiskers, super self::Animal::•(numberOfLegs)
+    ;
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
+    return other is self::Cat && this.{self::Animal::numberOfLegs}{core::int} =={core::num::==}{(core::Object) → core::bool} other{self::Cat}.{self::Animal::numberOfLegs}{core::int} && this.{self::Cat::numberOfWhiskers}{core::int} =={core::num::==}{(core::Object) → core::bool} other{self::Cat}.{self::Cat::numberOfWhiskers}{core::int};
+  get /*isLegacy*/ hashCode() → core::int
+    return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///value_extends_non_value.dartCat".{core::String::hashCode}{core::int}, this.{self::Animal::numberOfLegs}{core::int}.{core::num::hashCode}{core::int}), this.{self::Cat::numberOfWhiskers}{core::int}.{core::num::hashCode}{core::int}));
+  method /*isLegacy*/ toString() → core::String
+    return "Cat(numberOfLegs: ${this.{self::Animal::numberOfLegs}{core::int}.{core::int::toString}(){() → core::String}}, numberOfWhiskers: ${this.{self::Cat::numberOfWhiskers}{core::int}.{core::int::toString}(){() → core::String}})";
+  method /*isLegacy*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
+    return new self::Cat::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
+}
+static method main() → dynamic {
+  self::Cat firstCat = invalid-expression "pkg/front_end/testcases/value_class/value_extends_non_value.dart:18:22: Error: No named parameter with the name 'numberOfLegs'.
+  Cat firstCat = Cat(numberOfLegs: 4, numberOfWhiskers: 10);
+                     ^^^^^^^^^^^^";
+  self::Cat secondCat = invalid-expression "pkg/front_end/testcases/value_class/value_extends_non_value.dart:19:23: Error: No named parameter with the name 'numberOfLegs'.
+  Cat secondCat = Cat(numberOfLegs: 4, numberOfWhiskers: 10);
+                      ^^^^^^^^^^^^";
+  self::Cat thirdCat = invalid-expression "pkg/front_end/testcases/value_class/value_extends_non_value.dart:20:22: Error: No named parameter with the name 'numberOfLegs'.
+  Cat thirdCat = Cat(numberOfLegs: 4, numberOfWhiskers: 0);
+                     ^^^^^^^^^^^^";
+  self::expect(true, firstCat =={core::Object::==}{(core::Object) → core::bool} secondCat);
+  self::expect(false, firstCat =={core::Object::==}{(core::Object) → core::bool} thirdCat);
+  self::expect(true, firstCat.{core::Object::hashCode}{core::int} =={core::num::==}{(core::Object) → core::bool} secondCat.{core::Object::hashCode}{core::int});
+  self::expect(false, firstCat.{core::Object::hashCode}{core::int} =={core::num::==}{(core::Object) → core::bool} thirdCat.{core::Object::hashCode}{core::int});
+}
+static method expect(core::Object? expected, core::Object? actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected=${expected}, actual=${actual}";
+}
+
+library /*isNonNullableByDefault*/;
+import self as val;
+import "dart:core" as core;
+
+class JenkinsSmiHash extends core::Object {
+  synthetic constructor •() → val::JenkinsSmiHash
+    : super core::Object::•()
+    ;
+  static method combine(core::int hash, core::int value) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(value){(core::num) → core::int}){(core::int) → core::int};
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(524287.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(10){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    return hash.{core::int::^}(hash.{core::int::>>}(6){(core::int) → core::int}){(core::int) → core::int};
+  }
+  static method finish(core::int hash) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(67108863.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(3){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    hash = hash.{core::int::^}(hash.{core::int::>>}(11){(core::int) → core::int}){(core::int) → core::int};
+    return 536870911.{core::int::&}(hash.{core::num::+}(16383.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(15){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+  }
+}
+static const field core::String valueClass = #C2;
+
+constants  {
+  #C1 = null
+  #C2 = "valueClass"
+}
diff --git a/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.weak.modular.expect b/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.weak.modular.expect
new file mode 100644
index 0000000..068409c
--- /dev/null
+++ b/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.weak.modular.expect
@@ -0,0 +1,83 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/value_class/value_extends_non_value_error.dart:8:7: Error: Field 'numberOfLegs' should be initialized because its type 'int' doesn't allow null.
+//   int numberOfLegs;
+//       ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/value_class/value_extends_non_value_error.dart:15:13: Error: Final field 'numberOfLegs' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int numberOfLegs;
+//             ^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "value_class_support_lib.dart" as val;
+
+import "org-dartlang-testcase:///value_class_support_lib.dart";
+
+class Animal extends core::Object {
+  field core::int numberOfLegs = null;
+  synthetic constructor •() → self::Animal
+    : super core::Object::•()
+    ;
+}
+class Cat extends self::Animal {
+  synthetic constructor •() → self::Cat
+    : super self::Animal::•()
+    ;
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
+    return other is self::Cat;
+  get /*isLegacy*/ hashCode() → core::int
+    return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_extends_non_value_error.dartCat".{core::String::hashCode}{core::int});
+  method /*isLegacy*/ toString() → core::String
+    return "Cat()";
+  method /*isLegacy*/ copyWith() → dynamic
+    return new self::Cat::•();
+}
+class Animal2 extends core::Object {
+  final field core::int numberOfLegs = null;
+  synthetic constructor •() → self::Animal2
+    : super core::Object::•()
+    ;
+}
+class Cat2 extends self::Animal2 {
+  synthetic constructor •() → self::Cat2
+    : super self::Animal2::•()
+    ;
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
+    return other is self::Cat2;
+  get /*isLegacy*/ hashCode() → core::int
+    return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_extends_non_value_error.dartCat2".{core::String::hashCode}{core::int});
+  method /*isLegacy*/ toString() → core::String
+    return "Cat2()";
+  method /*isLegacy*/ copyWith() → dynamic
+    return new self::Cat2::•();
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as val;
+import "dart:core" as core;
+
+class JenkinsSmiHash extends core::Object {
+  synthetic constructor •() → val::JenkinsSmiHash
+    : super core::Object::•()
+    ;
+  static method combine(core::int hash, core::int value) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(value){(core::num) → core::int}){(core::int) → core::int};
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(524287.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(10){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    return hash.{core::int::^}(hash.{core::int::>>}(6){(core::int) → core::int}){(core::int) → core::int};
+  }
+  static method finish(core::int hash) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(67108863.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(3){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    hash = hash.{core::int::^}(hash.{core::int::>>}(11){(core::int) → core::int}){(core::int) → core::int};
+    return 536870911.{core::int::&}(hash.{core::num::+}(16383.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(15){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+  }
+}
+static const field core::String valueClass = #C1;
+
+constants  {
+  #C1 = "valueClass"
+}
diff --git a/pkg/front_end/testcases/value_class/value_implements_non_value.dart.weak.modular.expect b/pkg/front_end/testcases/value_class/value_implements_non_value.dart.weak.modular.expect
new file mode 100644
index 0000000..28477fa
--- /dev/null
+++ b/pkg/front_end/testcases/value_class/value_implements_non_value.dart.weak.modular.expect
@@ -0,0 +1,176 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:29:22: Error: No named parameter with the name 'numberOfLegs'.
+//   Cat firstCat = Cat(numberOfLegs: 4, numberOfWhiskers: 10);
+//                      ^^^^^^^^^^^^
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:12:7: Context: The class 'Cat' has a constructor that takes no arguments.
+// class Cat implements Animal {
+//       ^
+//
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:30:23: Error: No named parameter with the name 'numberOfLegs'.
+//   Cat secondCat = Cat(numberOfLegs: 4, numberOfWhiskers: 10);
+//                       ^^^^^^^^^^^^
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:12:7: Context: The class 'Cat' has a constructor that takes no arguments.
+// class Cat implements Animal {
+//       ^
+//
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:31:22: Error: No named parameter with the name 'numberOfLegs'.
+//   Cat thirdCat = Cat(numberOfLegs: 4, numberOfWhiskers: 0);
+//                      ^^^^^^^^^^^^
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:12:7: Context: The class 'Cat' has a constructor that takes no arguments.
+// class Cat implements Animal {
+//       ^
+//
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:39:25: Error: No named parameter with the name 'numberOfLegs'.
+//   Cat2 firstCat2 = Cat2(numberOfLegs: 4, numberOfWhiskers: 10);
+//                         ^^^^^^^^^^^^
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:22:7: Context: The class 'Cat2' has a constructor that takes no arguments.
+// class Cat2 implements Animal2 {
+//       ^
+//
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:40:26: Error: No named parameter with the name 'numberOfLegs'.
+//   Cat2 secondCat2 = Cat2(numberOfLegs: 4, numberOfWhiskers: 10);
+//                          ^^^^^^^^^^^^
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:22:7: Context: The class 'Cat2' has a constructor that takes no arguments.
+// class Cat2 implements Animal2 {
+//       ^
+//
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:41:25: Error: No named parameter with the name 'numberOfLegs'.
+//   Cat2 thirdCat2 = Cat2(numberOfLegs: 4, numberOfWhiskers: 0);
+//                         ^^^^^^^^^^^^
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:22:7: Context: The class 'Cat2' has a constructor that takes no arguments.
+// class Cat2 implements Animal2 {
+//       ^
+//
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:8:13: Error: Final field 'numberOfLegs' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int numberOfLegs;
+//             ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:13:13: Error: Final field 'numberOfLegs' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int numberOfLegs;
+//             ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:14:13: Error: Final field 'numberOfWhiskers' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int numberOfWhiskers;
+//             ^^^^^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:23:13: Error: Final field 'numberOfLegs' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int numberOfLegs;
+//             ^^^^^^^^^^^^
+//
+// pkg/front_end/testcases/value_class/value_implements_non_value.dart:24:13: Error: Final field 'numberOfWhiskers' is not initialized.
+// Try to initialize the field in the declaration or in every constructor.
+//   final int numberOfWhiskers;
+//             ^^^^^^^^^^^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+import "value_class_support_lib.dart" as val;
+
+import "org-dartlang-testcase:///value_class_support_lib.dart";
+
+class Animal extends core::Object {
+  final field core::int numberOfLegs = null;
+  synthetic constructor •() → self::Animal
+    : super core::Object::•()
+    ;
+}
+class Cat extends core::Object implements self::Animal {
+  final field core::int numberOfLegs = null;
+  final field core::int numberOfWhiskers = null;
+  synthetic constructor •({required core::int numberOfLegs, required core::int numberOfWhiskers}) → self::Cat
+    : self::Cat::numberOfLegs = numberOfLegs, self::Cat::numberOfWhiskers = numberOfWhiskers, super core::Object::•()
+    ;
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
+    return other is self::Cat && this.{self::Cat::numberOfLegs}{core::int} =={core::num::==}{(core::Object) → core::bool} other{self::Cat}.{self::Cat::numberOfLegs}{core::int} && this.{self::Cat::numberOfWhiskers}{core::int} =={core::num::==}{(core::Object) → core::bool} other{self::Cat}.{self::Cat::numberOfWhiskers}{core::int};
+  get /*isLegacy*/ hashCode() → core::int
+    return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///value_implements_non_value.dartCat".{core::String::hashCode}{core::int}, this.{self::Cat::numberOfLegs}{core::int}.{core::num::hashCode}{core::int}), this.{self::Cat::numberOfWhiskers}{core::int}.{core::num::hashCode}{core::int}));
+  method /*isLegacy*/ toString() → core::String
+    return "Cat(numberOfLegs: ${this.{self::Cat::numberOfLegs}{core::int}.{core::int::toString}(){() → core::String}}, numberOfWhiskers: ${this.{self::Cat::numberOfWhiskers}{core::int}.{core::int::toString}(){() → core::String}})";
+  method /*isLegacy*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
+    return new self::Cat::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
+}
+abstract class Animal2 extends core::Object {
+  synthetic constructor •() → self::Animal2
+    : super core::Object::•()
+    ;
+  abstract get numberOfLegs() → core::int;
+}
+class Cat2 extends core::Object implements self::Animal2 {
+  final field core::int numberOfLegs = null;
+  final field core::int numberOfWhiskers = null;
+  synthetic constructor •({required core::int numberOfLegs, required core::int numberOfWhiskers}) → self::Cat2
+    : self::Cat2::numberOfLegs = numberOfLegs, self::Cat2::numberOfWhiskers = numberOfWhiskers, super core::Object::•()
+    ;
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
+    return other is self::Cat2 && this.{self::Cat2::numberOfLegs}{core::int} =={core::num::==}{(core::Object) → core::bool} other{self::Cat2}.{self::Cat2::numberOfLegs}{core::int} && this.{self::Cat2::numberOfWhiskers}{core::int} =={core::num::==}{(core::Object) → core::bool} other{self::Cat2}.{self::Cat2::numberOfWhiskers}{core::int};
+  get /*isLegacy*/ hashCode() → core::int
+    return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///value_implements_non_value.dartCat2".{core::String::hashCode}{core::int}, this.{self::Cat2::numberOfLegs}{core::int}.{core::num::hashCode}{core::int}), this.{self::Cat2::numberOfWhiskers}{core::int}.{core::num::hashCode}{core::int}));
+  method /*isLegacy*/ toString() → core::String
+    return "Cat2(numberOfLegs: ${this.{self::Cat2::numberOfLegs}{core::int}.{core::int::toString}(){() → core::String}}, numberOfWhiskers: ${this.{self::Cat2::numberOfWhiskers}{core::int}.{core::int::toString}(){() → core::String}})";
+  method /*isLegacy*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
+    return new self::Cat2::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
+}
+static method main() → dynamic {
+  self::Cat firstCat = invalid-expression "pkg/front_end/testcases/value_class/value_implements_non_value.dart:29:22: Error: No named parameter with the name 'numberOfLegs'.
+  Cat firstCat = Cat(numberOfLegs: 4, numberOfWhiskers: 10);
+                     ^^^^^^^^^^^^";
+  self::Cat secondCat = invalid-expression "pkg/front_end/testcases/value_class/value_implements_non_value.dart:30:23: Error: No named parameter with the name 'numberOfLegs'.
+  Cat secondCat = Cat(numberOfLegs: 4, numberOfWhiskers: 10);
+                      ^^^^^^^^^^^^";
+  self::Cat thirdCat = invalid-expression "pkg/front_end/testcases/value_class/value_implements_non_value.dart:31:22: Error: No named parameter with the name 'numberOfLegs'.
+  Cat thirdCat = Cat(numberOfLegs: 4, numberOfWhiskers: 0);
+                     ^^^^^^^^^^^^";
+  self::expect(true, firstCat =={core::Object::==}{(core::Object) → core::bool} secondCat);
+  self::expect(false, firstCat =={core::Object::==}{(core::Object) → core::bool} thirdCat);
+  self::expect(true, firstCat.{core::Object::hashCode}{core::int} =={core::num::==}{(core::Object) → core::bool} secondCat.{core::Object::hashCode}{core::int});
+  self::expect(false, firstCat.{core::Object::hashCode}{core::int} =={core::num::==}{(core::Object) → core::bool} thirdCat.{core::Object::hashCode}{core::int});
+  self::Cat2 firstCat2 = invalid-expression "pkg/front_end/testcases/value_class/value_implements_non_value.dart:39:25: Error: No named parameter with the name 'numberOfLegs'.
+  Cat2 firstCat2 = Cat2(numberOfLegs: 4, numberOfWhiskers: 10);
+                        ^^^^^^^^^^^^";
+  self::Cat2 secondCat2 = invalid-expression "pkg/front_end/testcases/value_class/value_implements_non_value.dart:40:26: Error: No named parameter with the name 'numberOfLegs'.
+  Cat2 secondCat2 = Cat2(numberOfLegs: 4, numberOfWhiskers: 10);
+                         ^^^^^^^^^^^^";
+  self::Cat2 thirdCat2 = invalid-expression "pkg/front_end/testcases/value_class/value_implements_non_value.dart:41:25: Error: No named parameter with the name 'numberOfLegs'.
+  Cat2 thirdCat2 = Cat2(numberOfLegs: 4, numberOfWhiskers: 0);
+                        ^^^^^^^^^^^^";
+  self::expect(true, firstCat2 =={core::Object::==}{(core::Object) → core::bool} secondCat2);
+  self::expect(false, firstCat2 =={core::Object::==}{(core::Object) → core::bool} thirdCat2);
+  self::expect(true, firstCat2.{core::Object::hashCode}{core::int} =={core::num::==}{(core::Object) → core::bool} secondCat2.{core::Object::hashCode}{core::int});
+  self::expect(false, firstCat2.{core::Object::hashCode}{core::int} =={core::num::==}{(core::Object) → core::bool} thirdCat2.{core::Object::hashCode}{core::int});
+}
+static method expect(core::Object? expected, core::Object? actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual))
+    throw "Expected=${expected}, actual=${actual}";
+}
+
+library /*isNonNullableByDefault*/;
+import self as val;
+import "dart:core" as core;
+
+class JenkinsSmiHash extends core::Object {
+  synthetic constructor •() → val::JenkinsSmiHash
+    : super core::Object::•()
+    ;
+  static method combine(core::int hash, core::int value) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(value){(core::num) → core::int}){(core::int) → core::int};
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(524287.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(10){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    return hash.{core::int::^}(hash.{core::int::>>}(6){(core::int) → core::int}){(core::int) → core::int};
+  }
+  static method finish(core::int hash) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(67108863.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(3){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    hash = hash.{core::int::^}(hash.{core::int::>>}(11){(core::int) → core::int}){(core::int) → core::int};
+    return 536870911.{core::int::&}(hash.{core::num::+}(16383.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(15){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+  }
+}
+static const field core::String valueClass = #C1;
+
+constants  {
+  #C1 = "valueClass"
+}
diff --git a/pkg/front_end/testcases/value_class/value_mixin_error.dart.weak.modular.expect b/pkg/front_end/testcases/value_class/value_mixin_error.dart.weak.modular.expect
new file mode 100644
index 0000000..391ae35
--- /dev/null
+++ b/pkg/front_end/testcases/value_class/value_mixin_error.dart.weak.modular.expect
@@ -0,0 +1,71 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+import "value_class_support_lib.dart" as val;
+
+import "org-dartlang-testcase:///value_class_support_lib.dart";
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
+    return other is self::A;
+  get /*isLegacy*/ hashCode() → core::int
+    return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_mixin_error.dartA".{core::String::hashCode}{core::int});
+  method /*isLegacy*/ toString() → core::String
+    return "A()";
+  method /*isLegacy*/ copyWith() → dynamic
+    return new self::A::•();
+}
+class B extends core::Object {
+  synthetic constructor •() → self::B
+    : super core::Object::•()
+    ;
+}
+abstract class _C&B&A = self::B with self::A /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_C&B&A
+    : super self::B::•()
+    ;
+}
+class C extends self::_C&B&A {
+  synthetic constructor •() → self::C
+    : super self::_C&B&A::•()
+    ;
+}
+abstract class _D&A&B = self::A with self::B /*isAnonymousMixin*/  {
+  synthetic constructor •() → self::_D&A&B
+    : super self::A::•()
+    ;
+}
+class D extends self::_D&A&B {
+  synthetic constructor •() → self::D
+    : super self::_D&A&B::•()
+    ;
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as val;
+import "dart:core" as core;
+
+class JenkinsSmiHash extends core::Object {
+  synthetic constructor •() → val::JenkinsSmiHash
+    : super core::Object::•()
+    ;
+  static method combine(core::int hash, core::int value) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(value){(core::num) → core::int}){(core::int) → core::int};
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(524287.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(10){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    return hash.{core::int::^}(hash.{core::int::>>}(6){(core::int) → core::int}){(core::int) → core::int};
+  }
+  static method finish(core::int hash) → core::int {
+    hash = 536870911.{core::int::&}(hash.{core::num::+}(67108863.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(3){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+    hash = hash.{core::int::^}(hash.{core::int::>>}(11){(core::int) → core::int}){(core::int) → core::int};
+    return 536870911.{core::int::&}(hash.{core::num::+}(16383.{core::int::&}(hash){(core::int) → core::int}.{core::int::<<}(15){(core::int) → core::int}){(core::num) → core::int}){(core::int) → core::int};
+  }
+}
+static const field core::String valueClass = #C1;
+
+constants  {
+  #C1 = "valueClass"
+}
diff --git a/pkg/front_end/testcases/variance/class_type_parameter_modifier.dart.weak.modular.expect b/pkg/front_end/testcases/variance/class_type_parameter_modifier.dart.weak.modular.expect
new file mode 100644
index 0000000..14e8ddf
--- /dev/null
+++ b/pkg/front_end/testcases/variance/class_type_parameter_modifier.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A<X extends core::Object? = dynamic, contravariant Y extends core::Object? = dynamic, invariant Z extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::A<self::A::X%, self::A::Y%, self::A::Z%>
+    : super core::Object::•()
+    ;
+}
+static method main() → dynamic {
+  self::A<dynamic, dynamic, dynamic> a = new self::A::•<dynamic, dynamic, dynamic>();
+}
diff --git a/pkg/front_end/testcases/variance/generic_covariance_sound_variance.dart.weak.modular.expect b/pkg/front_end/testcases/variance/generic_covariance_sound_variance.dart.weak.modular.expect
new file mode 100644
index 0000000..5153118
--- /dev/null
+++ b/pkg/front_end/testcases/variance/generic_covariance_sound_variance.dart.weak.modular.expect
@@ -0,0 +1,128 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+typedef ContraFunction<contravariant T extends core::Object? = dynamic> = (T%) → void;
+typedef InvFunction<invariant T extends core::Object? = dynamic> = (T%) → T%;
+class Contravariant<contravariant T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Contravariant<self::Contravariant::T%>
+    : super core::Object::•()
+    ;
+}
+class Invariant<invariant T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Invariant<self::Invariant::T%>
+    : super core::Object::•()
+    ;
+}
+class A<contravariant T extends core::Object? = dynamic, U extends core::Object? = dynamic, V extends core::Object? = dynamic> extends core::Object {
+  final field (self::A::T%) →? void field = null;
+  synthetic constructor •() → self::A<self::A::T%, self::A::U%, self::A::V%>
+    : super core::Object::•()
+    ;
+  method method(self::A::T% t, (self::A::U%) → void u, covariant-by-class self::A::V% v) → void {}
+  method method2(self::A::T% x, [self::A::T? y = #C1]) → void {}
+  set x(self::A::T% t) → void {}
+  get mapContra() → core::Map<self::A::U%, self::Contravariant<self::A::V%>>
+    return core::Map::•<self::A::U%, self::Contravariant<self::A::V%>>();
+  get mapContraFn() → core::Map<self::A::U%, (self::A::V%) → void>
+    return core::Map::•<self::A::U%, (self::A::V%) → void>();
+  get mapInv() → core::Map<self::A::U%, self::Invariant<self::A::V%>>
+    return core::Map::•<self::A::U%, self::Invariant<self::A::V%>>();
+  get mapInvFn() → core::Map<self::A::U%, (self::A::V%) → self::A::V%>
+    return core::Map::•<self::A::U%, (self::A::V%) → self::A::V%>();
+}
+class B<invariant T extends core::Object? = dynamic> extends core::Object {
+  field self::B::T? x = null;
+  synthetic constructor •() → self::B<self::B::T%>
+    : super core::Object::•()
+    ;
+  method method(self::B::T% x) → self::B::T%
+    return x;
+  set y(self::B::T% x) → void {}
+}
+class C<contravariant T extends core::Object? = dynamic> extends core::Object {
+  final field (self::C::T%) →? void field = null;
+  synthetic constructor •() → self::C<self::C::T%>
+    : super core::Object::•()
+    ;
+  method method(self::C::T% x, [self::C::T? y = #C1]) → void {}
+  set x(self::C::T% t) → void {}
+}
+abstract class D<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::D<self::D::T%>
+    : super core::Object::•()
+    ;
+  abstract method method(covariant-by-class self::D::T% x) → core::int;
+}
+class E<invariant T extends core::Object? = dynamic> extends core::Object {
+  final field (self::E::T%) → void f;
+  constructor •((self::E::T%) → void f) → self::E<self::E::T%>
+    : self::E::f = f, super core::Object::•()
+    ;
+  method method(self::E::T% x) → core::int {
+    let final self::E::T% #t1 = x in this.{self::E::f}{(self::E::T%) → void}(#t1){(self::E::T%) → void};
+    return 0;
+  }
+}
+class F<invariant T extends core::Object? = dynamic> extends self::E<self::F::T%> implements self::D<self::F::T%> {
+  constructor •((self::F::T%) → void f) → self::F<self::F::T%>
+    : super self::E::•(f)
+    ;
+  forwarding-stub method method(covariant-by-class self::F::T% x) → core::int
+    return super.{self::E::method}(x);
+}
+class NoSuchMethod<invariant T extends core::Object? = dynamic> extends core::Object implements self::B<self::NoSuchMethod::T%> {
+  synthetic constructor •() → self::NoSuchMethod<self::NoSuchMethod::T%>
+    : super core::Object::•()
+    ;
+  method noSuchMethod(core::Invocation _) → dynamic
+    return 3;
+  no-such-method-forwarder get x() → self::NoSuchMethod::T?
+    return this.{self::NoSuchMethod::noSuchMethod}(new core::_InvocationMirror::_withType(#C2, 1, #C3, #C4, core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} self::NoSuchMethod::T?;
+  no-such-method-forwarder method method(self::NoSuchMethod::T% x) → self::NoSuchMethod::T%
+    return this.{self::NoSuchMethod::noSuchMethod}(new core::_InvocationMirror::_withType(#C6, 0, #C3, core::List::unmodifiable<dynamic>(<dynamic>[x]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic} as{TypeError,ForDynamic,ForNonNullableByDefault} self::NoSuchMethod::T%;
+  no-such-method-forwarder set y(self::NoSuchMethod::T% x) → void
+    return this.{self::NoSuchMethod::noSuchMethod}(new core::_InvocationMirror::_withType(#C7, 2, #C3, core::List::unmodifiable<dynamic>(<dynamic>[x]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+  no-such-method-forwarder set x(self::NoSuchMethod::T? value) → void
+    return this.{self::NoSuchMethod::noSuchMethod}(new core::_InvocationMirror::_withType(#C8, 2, #C3, core::List::unmodifiable<dynamic>(<dynamic>[value]), core::Map::unmodifiable<core::Symbol*, dynamic>(#C5))){(core::Invocation) → dynamic};
+}
+static method main() → dynamic {
+  self::A<core::int, core::num, core::String> a = new self::A::•<core::int, core::num, core::String>();
+  self::expect(null, a.{self::A::field}{(core::int) →? void});
+  a.{self::A::method}(3, (core::num num) → void {}, "test"){(core::int, (core::num) → void, core::String) → void};
+  a.{self::A::method2}(3){(core::int, [core::int?]) → void};
+  a.{self::A::x} = 3;
+  core::Map<core::num, self::Contravariant<core::String>> mapContra = a.{self::A::mapContra}{core::Map<core::num, self::Contravariant<core::String>>} as{TypeError,CovarianceCheck,ForNonNullableByDefault} core::Map<core::num, self::Contravariant<core::String>>;
+  core::Map<core::num, (core::String) → void> mapContraFn = a.{self::A::mapContraFn}{core::Map<core::num, (core::String) → void>} as{TypeError,CovarianceCheck,ForNonNullableByDefault} core::Map<core::num, (core::String) → void>;
+  core::Map<core::num, self::Invariant<core::String>> mapInv = a.{self::A::mapInv}{core::Map<core::num, self::Invariant<core::String>>} as{TypeError,CovarianceCheck,ForNonNullableByDefault} core::Map<core::num, self::Invariant<core::String>>;
+  core::Map<core::num, (core::String) → core::String> mapInvFn = a.{self::A::mapInvFn}{core::Map<core::num, (core::String) → core::String>} as{TypeError,CovarianceCheck,ForNonNullableByDefault} core::Map<core::num, (core::String) → core::String>;
+  self::B<core::int> b = new self::B::•<core::int>();
+  b.{self::B::x} = 3;
+  self::expect(3, b.{self::B::x}{core::int?});
+  self::expect(3, b.{self::B::method}(3){(core::int) → core::int});
+  b.{self::B::y} = 3;
+  self::C<core::int> c = new self::C::•<core::int>();
+  self::expect(null, c.{self::C::field}{(core::int) →? void});
+  c.{self::C::method}(3, 2){(core::int, [core::int?]) → void};
+  c.{self::C::x} = 3;
+  self::D<core::Object> d = new self::F::•<core::String>((core::String s) → void {});
+  d.{self::D::method}("test"){(core::Object) → core::int};
+  self::NoSuchMethod<core::num> nsm = new self::NoSuchMethod::•<core::num>();
+  self::expect(3, nsm.{self::B::method}(3){(core::num) → core::num});
+}
+static method expect(dynamic expected, dynamic actual) → dynamic {
+  if(!(expected =={core::Object::==}{(core::Object) → core::bool} actual)) {
+    throw "Mismatch: expected=${expected}, actual=${actual}";
+  }
+}
+
+constants  {
+  #C1 = null
+  #C2 = #x
+  #C3 = <core::Type*>[]
+  #C4 = <dynamic>[]
+  #C5 = <core::Symbol*, dynamic>{)
+  #C6 = #method
+  #C7 = #y=
+  #C8 = #x=
+}
diff --git a/pkg/front_end/testcases/variance/mixin_type_parameter_modifier.dart.weak.modular.expect b/pkg/front_end/testcases/variance/mixin_type_parameter_modifier.dart.weak.modular.expect
new file mode 100644
index 0000000..abd3eea
--- /dev/null
+++ b/pkg/front_end/testcases/variance/mixin_type_parameter_modifier.dart.weak.modular.expect
@@ -0,0 +1,12 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class A extends core::Object {
+  synthetic constructor •() → self::A
+    : super core::Object::•()
+    ;
+}
+abstract class B<invariant X extends core::Object? = dynamic, Y extends core::Object? = dynamic, contravariant Z extends core::Object? = dynamic> extends self::A /*isMixinDeclaration*/  {
+}
+static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/variance/unconstrained_inference.dart.weak.modular.expect b/pkg/front_end/testcases/variance/unconstrained_inference.dart.weak.modular.expect
new file mode 100644
index 0000000..0850650
--- /dev/null
+++ b/pkg/front_end/testcases/variance/unconstrained_inference.dart.weak.modular.expect
@@ -0,0 +1,30 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+class Covariant<T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Covariant<self::Covariant::T%>
+    : super core::Object::•()
+    ;
+}
+class Contravariant<contravariant T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Contravariant<self::Contravariant::T%>
+    : super core::Object::•()
+    ;
+}
+class Invariant<invariant T extends core::Object? = dynamic> extends core::Object {
+  synthetic constructor •() → self::Invariant<self::Invariant::T%>
+    : super core::Object::•()
+    ;
+}
+static method covariantListInfer<T extends core::Object? = dynamic>(self::Covariant<core::List<self::covariantListInfer::T%>> x) → void {}
+static method contravariantListInfer<T extends core::Object? = dynamic>(self::Contravariant<core::List<self::contravariantListInfer::T%>> x) → void {}
+static method invariantListInfer<T extends core::Object? = dynamic>(self::Invariant<core::List<self::invariantListInfer::T%>> x) → void {}
+static method main() → dynamic {
+  self::Covariant<dynamic> cov = new self::Covariant::•<dynamic>();
+  self::covariantListInfer<core::Object?>(new self::Covariant::•<core::List<core::Object?>>());
+  self::Contravariant<Never> contra = new self::Contravariant::•<Never>();
+  self::contravariantListInfer<core::Object?>(new self::Contravariant::•<core::List<core::Object?>>());
+  self::Invariant<dynamic> inv = new self::Invariant::•<dynamic>();
+  self::invariantListInfer<core::Object?>(new self::Invariant::•<core::List<core::Object?>>());
+}
diff --git a/pkg/front_end/testcases/weak.status b/pkg/front_end/testcases/weak.status
index 9c9ea5e..ae8b870 100644
--- a/pkg/front_end/testcases/weak.status
+++ b/pkg/front_end/testcases/weak.status
@@ -4,6 +4,8 @@
 
 # Status file for the weak_suite.dart test suite.
 
+dart2js/flutter_issue94561/main: SemiFuzzFailure
+dart2js/flutter_issue94561/main.no_link: SemiFuzzFailure
 dart2js/late_fields: SemiFuzzFailure
 dart2js/late_from_dill/main: SemiFuzzFailure
 dart2js/late_statics: SemiFuzzFailure
@@ -12,7 +14,6 @@
 general/error_recovery/issue_39058_prime.crash: SemiFuzzFailure
 general/error_recovery/issue_39202.crash: SemiFuzzCrash
 general/error_recovery/issue_39058.crash: SemiFuzzFailure
-general/issue47339: SemiFuzzCrash
 general/platform_invalid_uris/main: SemiFuzzFailure
 nnbd_mixed/mixin_from_opt_in/main: SemiFuzzFailure
 nnbd_mixed/mixin_from_opt_in/main.no_link: SemiFuzzFailure
diff --git a/pkg/front_end/testing.json b/pkg/front_end/testing.json
index 11fca520..d0f87bb 100644
--- a/pkg/front_end/testing.json
+++ b/pkg/front_end/testing.json
@@ -128,6 +128,23 @@
       ]
     },
     {
+      "name": "modular",
+      "kind": "Chain",
+      "source": "test/fasta/modular_suite.dart",
+      "path": "testcases/",
+      "status": "testcases/modular.status",
+      "pattern": [
+        "\\.dart$",
+        "\\.crash_dart$"
+      ],
+      "exclude": [
+        "/testcases/.*_part[0-9]*\\.dart$",
+        "/testcases/.*_lib[0-9]*\\.dart$",
+        "/testcases/dartino/",
+        "/testcases/expression/"
+      ]
+    },
+    {
       "name": "weak",
       "kind": "Chain",
       "source": "test/fasta/weak_suite.dart",
diff --git a/pkg/front_end/tool/_fasta/command_line.dart b/pkg/front_end/tool/_fasta/command_line.dart
index 0c8312e..58d7517 100644
--- a/pkg/front_end/tool/_fasta/command_line.dart
+++ b/pkg/front_end/tool/_fasta/command_line.dart
@@ -277,7 +277,7 @@
           ..sdkSummary = Options.platform.read(parsedOptions)
           ..librariesSpecificationUri = resolveInputUri(arguments[1])
           ..setExitCodeOnProblem = true,
-        inputs: <Uri>[Uri.parse(arguments[0])],
+        inputs: arguments[0].split(',').map(Uri.parse).toList(),
         output: resolveInputUri(arguments[3]));
   } else if (arguments.isEmpty) {
     return throw new CommandLineProblem.deprecated("No Dart file specified.");
diff --git a/pkg/front_end/tool/_fasta/compile_platform_legacy_test.dart b/pkg/front_end/tool/_fasta/compile_platform_legacy_test.dart
index 073dd5f..b7b6fa6 100644
--- a/pkg/front_end/tool/_fasta/compile_platform_legacy_test.dart
+++ b/pkg/front_end/tool/_fasta/compile_platform_legacy_test.dart
@@ -36,6 +36,30 @@
       Expect.isTrue(await new File.fromUri(outlineDill).exists());
     });
   });
+
+  asyncTest(() async {
+    await withTemporaryDirectory("compile_platform_test_", (Uri tmp) async {
+      Uri platformDill = tmp.resolve("dart2js_platform.dill");
+      Uri outlineDill = tmp.resolve("dart2js_outline.dill");
+      ProcessResult result = await Process.run(dartVm.toFilePath(), <String>[
+        compilePlatform.toFilePath(),
+        "--target=dart2js",
+        "--no-deps",
+        "-v",
+        "dart:core,dart:js_util",
+        librariesJson.toFilePath(),
+        outlineDill.toFilePath(),
+        platformDill.toFilePath(),
+        outlineDill.toFilePath(),
+      ]);
+      stdout.write(result.stdout);
+      stderr.write(result.stderr);
+      Expect.equals(
+          0, result.exitCode, "Non-zero exitcode from compile_platform.dart");
+      Expect.isTrue(await new File.fromUri(platformDill).exists());
+      Expect.isTrue(await new File.fromUri(outlineDill).exists());
+    });
+  });
 }
 
 Future<void> withTemporaryDirectory(
diff --git a/pkg/front_end/tool/_fasta/compile_platform_test.dart b/pkg/front_end/tool/_fasta/compile_platform_test.dart
index 073dd5f..b7b6fa6 100644
--- a/pkg/front_end/tool/_fasta/compile_platform_test.dart
+++ b/pkg/front_end/tool/_fasta/compile_platform_test.dart
@@ -36,6 +36,30 @@
       Expect.isTrue(await new File.fromUri(outlineDill).exists());
     });
   });
+
+  asyncTest(() async {
+    await withTemporaryDirectory("compile_platform_test_", (Uri tmp) async {
+      Uri platformDill = tmp.resolve("dart2js_platform.dill");
+      Uri outlineDill = tmp.resolve("dart2js_outline.dill");
+      ProcessResult result = await Process.run(dartVm.toFilePath(), <String>[
+        compilePlatform.toFilePath(),
+        "--target=dart2js",
+        "--no-deps",
+        "-v",
+        "dart:core,dart:js_util",
+        librariesJson.toFilePath(),
+        outlineDill.toFilePath(),
+        platformDill.toFilePath(),
+        outlineDill.toFilePath(),
+      ]);
+      stdout.write(result.stdout);
+      stderr.write(result.stderr);
+      Expect.equals(
+          0, result.exitCode, "Non-zero exitcode from compile_platform.dart");
+      Expect.isTrue(await new File.fromUri(platformDill).exists());
+      Expect.isTrue(await new File.fromUri(outlineDill).exists());
+    });
+  });
 }
 
 Future<void> withTemporaryDirectory(
diff --git a/pkg/front_end/tool/_fasta/parser_ast_helper_creator.dart b/pkg/front_end/tool/_fasta/parser_ast_helper_creator.dart
index b9999d6..ff1f22e 100644
--- a/pkg/front_end/tool/_fasta/parser_ast_helper_creator.dart
+++ b/pkg/front_end/tool/_fasta/parser_ast_helper_creator.dart
@@ -103,7 +103,8 @@
   ParserCreatorListener(this.out);
 
   @override
-  void beginClassDeclaration(Token begin, Token? abstractToken, Token name) {
+  void beginClassDeclaration(
+      Token begin, Token? abstractToken, Token? macroToken, Token name) {
     if (name.lexeme == "Listener") insideListenerClass = true;
   }
 
diff --git a/pkg/front_end/tool/dart_doctest_impl.dart b/pkg/front_end/tool/dart_doctest_impl.dart
index 64d0aa7..b03351a 100644
--- a/pkg/front_end/tool/dart_doctest_impl.dart
+++ b/pkg/front_end/tool/dart_doctest_impl.dart
@@ -800,9 +800,8 @@
     assert(dillTargetForTesting != null && kernelTargetForTesting != null);
 
     return await context.runInContext((_) async {
-      LibraryBuilder libraryBuilder = kernelTargetForTesting!.loader.read(
-          libraryUri, -1,
-          accessorUri: kernelTargetForTesting!.loader.firstUri);
+      LibraryBuilder libraryBuilder =
+          kernelTargetForTesting!.loader.readAsEntryPoint(libraryUri);
 
       kernelTargetForTesting!.loader.resetSeenMessages();
 
@@ -826,12 +825,11 @@
   SourceLibraryBuilder createDartDocTestLibrary(
       SourceLoader loader, LibraryBuilder libraryBuilder) {
     SourceLibraryBuilder dartDocTestLibrary = new SourceLibraryBuilder(
-      dartDocTestUri,
-      dartDocTestUri,
-      /*packageUri*/ null,
-      new ImplicitLanguageVersion(libraryBuilder.library.languageVersion),
-      loader,
-      null,
+      importUri: dartDocTestUri,
+      fileUri: dartDocTestUri,
+      packageLanguageVersion:
+          new ImplicitLanguageVersion(libraryBuilder.library.languageVersion),
+      loader: loader,
       scope: libraryBuilder.scope.createNestedScope("dartdoctest"),
       nameOrigin: libraryBuilder,
     );
@@ -899,14 +897,14 @@
 
   @override
   SourceLibraryBuilder createLibraryBuilder(
-      Uri uri,
-      Uri fileUri,
+      {required Uri importUri,
+      required Uri fileUri,
       Uri? packageUri,
-      LanguageVersion packageLanguageVersion,
+      required LanguageVersion packageLanguageVersion,
       SourceLibraryBuilder? origin,
       kernel.Library? referencesFrom,
-      bool? referenceIsPartOwner) {
-    if (uri == DocTestIncrementalCompiler.dartDocTestUri) {
+      bool? referenceIsPartOwner}) {
+    if (importUri == DocTestIncrementalCompiler.dartDocTestUri) {
       HybridFileSystem hfs = target.fileSystem as HybridFileSystem;
       MemoryFileSystem fs = hfs.memory;
       fs
@@ -915,7 +913,13 @@
       return compiler.createDartDocTestLibrary(
           this, compiler._dartDocTestLibraryBuilder!);
     }
-    return super.createLibraryBuilder(uri, fileUri, packageUri,
-        packageLanguageVersion, origin, referencesFrom, referenceIsPartOwner);
+    return super.createLibraryBuilder(
+        importUri: importUri,
+        fileUri: fileUri,
+        packageUri: packageUri,
+        packageLanguageVersion: packageLanguageVersion,
+        origin: origin,
+        referencesFrom: referencesFrom,
+        referenceIsPartOwner: referenceIsPartOwner);
   }
 }
diff --git a/pkg/front_end/tool/update_expectations.dart b/pkg/front_end/tool/update_expectations.dart
index 45d7ef3..8a99e2e 100644
--- a/pkg/front_end/tool/update_expectations.dart
+++ b/pkg/front_end/tool/update_expectations.dart
@@ -8,6 +8,7 @@
   'weak',
   'outline',
   'strong',
+  'modular',
   'text_serialization',
   'textual_outline',
 ];
diff --git a/pkg/frontend_server/lib/frontend_server.dart b/pkg/frontend_server/lib/frontend_server.dart
index 706448e..7563736 100644
--- a/pkg/frontend_server/lib/frontend_server.dart
+++ b/pkg/frontend_server/lib/frontend_server.dart
@@ -55,6 +55,9 @@
       help:
           'Enable global type flow analysis and related transformations in AOT mode.',
       defaultsTo: false)
+  ..addFlag('rta',
+      help: 'Use rapid type analysis for faster compilation in AOT mode.',
+      defaultsTo: true)
   ..addFlag('tree-shake-write-only-fields',
       help: 'Enable tree shaking of fields which are only written in AOT mode.',
       defaultsTo: true)
@@ -555,6 +558,7 @@
           deleteToStringPackageUris: options['delete-tostring-package-uri'],
           aot: options['aot'],
           useGlobalTypeFlowAnalysis: options['tfa'],
+          useRapidTypeAnalysis: options['rta'],
           environmentDefines: environmentDefines,
           enableAsserts: options['enable-asserts'],
           useProtobufTreeShakerV2: options['protobuf-tree-shaker-v2'],
diff --git a/pkg/js/CHANGELOG.md b/pkg/js/CHANGELOG.md
index 571726d..8c22600 100644
--- a/pkg/js/CHANGELOG.md
+++ b/pkg/js/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 0.6.4
+
+* Includes `@staticInterop` to allow interop with native types from `dart:html`.
+
 ## 0.6.3
 
 * Stable release for null safety.
diff --git a/pkg/js/README.md b/pkg/js/README.md
index 7279082..4f75675 100644
--- a/pkg/js/README.md
+++ b/pkg/js/README.md
@@ -131,6 +131,48 @@
 }
 ```
 
+## Interop with native types using `@staticInterop`
+
+Previously, you could not use `@JS()` or `@anonymous` types to interface with
+native types that were reserved within `dart:html` e.g. `Window`.
+
+Using `@staticInterop` will now let you do so. However, it requires that there
+be no instance members within the class (constructors are still allowed). You
+can use static extension methods instead to declare these members. For example:
+
+```dart
+@JS()
+library static_interop;
+
+import 'dart:html' as html;
+
+import 'package:js/js.dart';
+
+@JS()
+@staticInterop
+class JSWindow {}
+
+extension JSWindowExtension on JSWindow {
+  external String get name;
+  String get nameAllCaps => name.toUpperCase();
+}
+
+void main() {
+  var jsWindow = html.window as JSWindow;
+  print(jsWindow.name.toUpperCase() == jsWindow.nameAllCaps);
+}
+```
+
+Note that in the above you can have both `external` and non-`external` members
+in the extension. You can have `external` variables, getters/setters, and
+methods within a static extension currently. These `external` members are
+lowered to their respective `js_util` calls under the hood. For example, the
+`external` `name` getter is equivalent to `js_util.getProperty(this, 'name')`.
+
+In general, it's advised to use `@staticInterop` wherever you can over using
+just `@JS()`. There will be fewer surprises and it's aligned with the statically
+typed future planned for JS interop.
+
 ## Reporting issues
 
 Please file bugs and feature requests on the [SDK issue tracker][issues].
diff --git a/pkg/js/lib/js.dart b/pkg/js/lib/js.dart
index 1c099c3..5f41532 100644
--- a/pkg/js/lib/js.dart
+++ b/pkg/js/lib/js.dart
@@ -25,9 +25,9 @@
   const _Anonymous();
 }
 
-// class _StaticInterop {
-//   const _StaticInterop();
-// }
+class _StaticInterop {
+  const _StaticInterop();
+}
 
 /// An annotation that indicates a [JS] annotated class is structural and does
 /// not have a known JavaScript prototype.
@@ -44,6 +44,4 @@
 /// These classes allow interop with native types, like the ones in `dart:html`.
 /// These classes should not contain any instance members, inherited or
 /// otherwise, and should instead use static extension members.
-// TODO(47324, 47325): Uncomment these annotations once erasure and subtyping
-// are ready.
-// const _StaticInterop staticInterop = _StaticInterop();
+const _StaticInterop staticInterop = _StaticInterop();
diff --git a/pkg/js/pubspec.yaml b/pkg/js/pubspec.yaml
index 44b80a9..40fde9c 100644
--- a/pkg/js/pubspec.yaml
+++ b/pkg/js/pubspec.yaml
@@ -1,10 +1,10 @@
 name: js
-version: 0.6.3
+version: 0.6.4
 description: Annotations to create static Dart interfaces for JavaScript APIs.
 homepage: https://github.com/dart-lang/sdk/tree/master/pkg/js
 
 environment:
-  sdk: ">=2.12.0-0 <3.0.0"
+  sdk: ">=2.16.0-100.0.dev <3.0.0"
 
 dev_dependencies:
   pedantic: ^1.9.0
diff --git a/pkg/js_ast/lib/src/nodes.dart b/pkg/js_ast/lib/src/nodes.dart
index 0d4e490..56a2b40 100644
--- a/pkg/js_ast/lib/src/nodes.dart
+++ b/pkg/js_ast/lib/src/nodes.dart
@@ -85,13 +85,11 @@
   T visitInterpolatedDeclaration(InterpolatedDeclaration node);
 }
 
-class BaseVisitor<T> implements NodeVisitor<T> {
+abstract class BaseVisitor<T> implements NodeVisitor<T> {
   const BaseVisitor();
 
-  T visitNode(Node node) {
-    node.visitChildren(this);
-    return null;
-  }
+  T visitNode(Node node);
+  T visitComment(Comment node);
 
   T visitProgram(Program node) => visitNode(node);
 
@@ -198,13 +196,19 @@
     return visitInterpolatedNode(node);
   }
 
-  // Ignore comments by default.
-  T visitComment(Comment node) => null;
-
   T visitAwait(Await node) => visitExpression(node);
   T visitDartYield(DartYield node) => visitStatement(node);
 }
 
+class BaseVisitorVoid extends BaseVisitor<void> {
+  void visitNode(Node node) {
+    node.visitChildren(this);
+  }
+
+  // Ignore comments by default.
+  void visitComment(Comment node) {}
+}
+
 abstract class NodeVisitor1<R, A> {
   R visitProgram(Program node, A arg);
 
@@ -286,13 +290,11 @@
   R visitInterpolatedDeclaration(InterpolatedDeclaration node, A arg);
 }
 
-class BaseVisitor1<R, A> implements NodeVisitor1<R, A> {
+abstract class BaseVisitor1<R, A> implements NodeVisitor1<R, A> {
   const BaseVisitor1();
 
-  R visitNode(Node node, A arg) {
-    node.visitChildren1(this, arg);
-    return null;
-  }
+  R visitNode(Node node, A arg);
+  R visitComment(Comment node, A arg);
 
   R visitProgram(Program node, A arg) => visitNode(node, arg);
 
@@ -412,13 +414,19 @@
     return visitInterpolatedNode(node, arg);
   }
 
-  // Ignore comments by default.
-  R visitComment(Comment node, A arg) => null;
-
   R visitAwait(Await node, A arg) => visitExpression(node, arg);
   R visitDartYield(DartYield node, A arg) => visitStatement(node, arg);
 }
 
+class BaseVisitor1Void<A> extends BaseVisitor1<void, A> {
+  void visitNode(Node node, A arg) {
+    node.visitChildren1(this, arg);
+  }
+
+  // Ignore comments by default.
+  void visitComment(Comment node, A arg) {}
+}
+
 /// This tag interface has no behaviour but must be implemented by any class
 /// that is to be stored on a [Node] as source information.
 abstract class JavaScriptNodeSourceInformation {
diff --git a/pkg/js_ast/lib/src/printer.dart b/pkg/js_ast/lib/src/printer.dart
index 0f3c329..d5eb576 100644
--- a/pkg/js_ast/lib/src/printer.dart
+++ b/pkg/js_ast/lib/src/printer.dart
@@ -1476,7 +1476,7 @@
   }
 }
 
-class _StringContentsCollector extends BaseVisitor<void> {
+class _StringContentsCollector extends BaseVisitorVoid {
   final StringBuffer _buffer = StringBuffer();
   final bool isDebugContext;
 
@@ -1551,7 +1551,7 @@
 
 // Collects all the var declarations in the function.  We need to do this in a
 // separate pass because JS vars are lifted to the top of the function.
-class VarCollector extends BaseVisitor {
+class VarCollector extends BaseVisitorVoid {
   bool nested;
   bool enableRenaming = true;
   final OrderedSet<String> vars;
@@ -1630,9 +1630,11 @@
 
   bool visitNode(Node node) {
     context.error("Forgot node: $node");
-    return null;
+    return true;
   }
 
+  bool visitComment(Comment node) => true;
+
   bool visitBlock(Block node) => false;
   bool visitExpressionStatement(ExpressionStatement node) => false;
   bool visitEmptyStatement(EmptyStatement node) => false;
diff --git a/pkg/js_ast/lib/src/template.dart b/pkg/js_ast/lib/src/template.dart
index 239a717..bdcf3c0 100644
--- a/pkg/js_ast/lib/src/template.dart
+++ b/pkg/js_ast/lib/src/template.dart
@@ -775,7 +775,7 @@
 
 /// InterpolatedNodeAnalysis determines which AST trees contain
 /// [InterpolatedNode]s, and the names of the named interpolated nodes.
-class InterpolatedNodeAnalysis extends BaseVisitor {
+class InterpolatedNodeAnalysis extends BaseVisitorVoid {
   final Set<Node> containsInterpolatedNode = {};
   final Set<String> holeNames = {};
   int count = 0;
diff --git a/pkg/kernel/binary.md b/pkg/kernel/binary.md
index e710da2..b75aba6 100644
--- a/pkg/kernel/binary.md
+++ b/pkg/kernel/binary.md
@@ -147,7 +147,7 @@
 
 type ComponentFile {
   UInt32 magic = 0x90ABCDEF;
-  UInt32 formatVersion = 74;
+  UInt32 formatVersion = 75;
   Byte[10] shortSdkHash;
   List<String> problemsAsJson; // Described in problems.md.
   Library[] libraries;
@@ -316,7 +316,7 @@
   FileOffset fileOffset; // Offset of the name of the class.
   FileOffset fileEndOffset;
   Byte flags (isAbstract, isEnum, isAnonymousMixin, isEliminatedMixin,
-              isMixinDeclaration, hasConstConstructor);
+              isMixinDeclaration, hasConstConstructor, isMacro);
   StringReference name;
   List<Expression> annotations;
   List<TypeParameter> typeParameters;
diff --git a/pkg/kernel/lib/ast.dart b/pkg/kernel/lib/ast.dart
index 86800bb..99a2f86 100644
--- a/pkg/kernel/lib/ast.dart
+++ b/pkg/kernel/lib/ast.dart
@@ -1013,6 +1013,7 @@
   static const int FlagEliminatedMixin = 1 << 3;
   static const int FlagMixinDeclaration = 1 << 4;
   static const int FlagHasConstConstructor = 1 << 5;
+  static const int FlagMacro = 1 << 6;
 
   int flags = 0;
 
@@ -1029,6 +1030,13 @@
     flags = value ? (flags | FlagEnum) : (flags & ~FlagEnum);
   }
 
+  /// Whether this class is a macro class.
+  bool get isMacro => flags & FlagMacro != 0;
+
+  void set isMacro(bool value) {
+    flags = value ? (flags | FlagMacro) : (flags & ~FlagMacro);
+  }
+
   /// Whether this class is a synthetic implementation created for each
   /// mixed-in class. For example the following code:
   /// class Z extends A with B, C, D {}
@@ -11888,7 +11896,9 @@
       v.visitTypeParameterType(this, arg);
 
   @override
-  void visitChildren(Visitor v) {}
+  void visitChildren(Visitor v) {
+    promotedBound?.accept(v);
+  }
 
   @override
   bool operator ==(Object other) => equals(other, null);
diff --git a/pkg/kernel/lib/binary/ast_to_binary.dart b/pkg/kernel/lib/binary/ast_to_binary.dart
index 4cf39b7..dc9ece8 100644
--- a/pkg/kernel/lib/binary/ast_to_binary.dart
+++ b/pkg/kernel/lib/binary/ast_to_binary.dart
@@ -2498,6 +2498,8 @@
       writeName(descriptor.name);
       writeByte(descriptor.kind.index);
       writeByte(descriptor.flags);
+      assert(descriptor.member.canonicalName != null,
+          "No canonical name for ${descriptor}.");
       writeNonNullCanonicalNameReference(descriptor.member.canonicalName!);
     }
   }
diff --git a/pkg/kernel/lib/binary/tag.dart b/pkg/kernel/lib/binary/tag.dart
index 859ed11..ceaae4a 100644
--- a/pkg/kernel/lib/binary/tag.dart
+++ b/pkg/kernel/lib/binary/tag.dart
@@ -176,7 +176,7 @@
   /// Internal version of kernel binary format.
   /// Bump it when making incompatible changes in kernel binaries.
   /// Keep in sync with runtime/vm/kernel_binary.h, pkg/kernel/binary.md.
-  static const int BinaryFormatVersion = 74;
+  static const int BinaryFormatVersion = 75;
 }
 
 abstract class ConstantTag {
diff --git a/pkg/kernel/lib/class_hierarchy.dart b/pkg/kernel/lib/class_hierarchy.dart
index 43368ec..e231e8f 100644
--- a/pkg/kernel/lib/class_hierarchy.dart
+++ b/pkg/kernel/lib/class_hierarchy.dart
@@ -38,17 +38,6 @@
   List<DartType>? getTypeArgumentsAsInstanceOf(
       InterfaceType type, Class superclass);
 
-  /// Returns the possibly abstract interface member of [class_] with the given
-  /// [name].
-  ///
-  /// If [setter] is `false`, only fields, methods, and getters with that name
-  /// will be found.  If [setter] is `true`, only non-final fields and setters
-  /// will be found.
-  ///
-  /// If multiple members with that name are inherited and not overridden, the
-  /// member from the first declared supertype is returned.
-  Member? getInterfaceMember(Class class_, Name name, {bool setter: false});
-
   /// Returns the least upper bound of two interface types, as defined by Dart
   /// 1.0.
   ///
@@ -68,8 +57,22 @@
       InterfaceType type1, InterfaceType type2, Library clientLibrary);
 }
 
+abstract class ClassHierarchyMembers {
+  /// Returns the possibly abstract interface member of [class_] with the given
+  /// [name].
+  ///
+  /// If [setter] is `false`, only fields, methods, and getters with that name
+  /// will be found.  If [setter] is `true`, only non-final fields and setters
+  /// will be found.
+  ///
+  /// If multiple members with that name are inherited and not overridden, the
+  /// member from the first declared supertype is returned.
+  Member? getInterfaceMember(Class class_, Name name, {bool setter: false});
+}
+
 /// Interface for answering various subclassing queries.
-abstract class ClassHierarchy implements ClassHierarchyBase {
+abstract class ClassHierarchy
+    implements ClassHierarchyBase, ClassHierarchyMembers {
   factory ClassHierarchy(Component component, CoreTypes coreTypes,
       {HandleAmbiguousSupertypes? onAmbiguousSupertypes,
       MixinInferrer? mixinInferrer}) {
diff --git a/pkg/kernel/lib/src/hierarchy_based_type_environment.dart b/pkg/kernel/lib/src/hierarchy_based_type_environment.dart
index 65894ac..15812bf 100644
--- a/pkg/kernel/lib/src/hierarchy_based_type_environment.dart
+++ b/pkg/kernel/lib/src/hierarchy_based_type_environment.dart
@@ -6,7 +6,7 @@
 
 import '../ast.dart' show Class, DartType, InterfaceType, Library, Member, Name;
 
-import '../class_hierarchy.dart' show ClassHierarchyBase;
+import '../class_hierarchy.dart' show ClassHierarchy;
 
 import '../core_types.dart' show CoreTypes;
 
@@ -14,7 +14,7 @@
 
 class HierarchyBasedTypeEnvironment extends TypeEnvironment {
   @override
-  final ClassHierarchyBase hierarchy;
+  final ClassHierarchy hierarchy;
 
   HierarchyBasedTypeEnvironment(CoreTypes coreTypes, this.hierarchy)
       : super.fromSubclass(coreTypes, hierarchy);
diff --git a/pkg/kernel/lib/target/targets.dart b/pkg/kernel/lib/target/targets.dart
index 14f30a3..804f26a 100644
--- a/pkg/kernel/lib/target/targets.dart
+++ b/pkg/kernel/lib/target/targets.dart
@@ -268,13 +268,12 @@
   bool mayDefineRestrictedType(Uri uri) =>
       uri.isScheme('dart') && (uri.path == 'core' || uri.path == 'typed_data');
 
-  /// Whether a library is allowed to import a platform private library.
+  /// Whether a library is allowed to import the platform private library
+  /// [imported] from library [importer].
   ///
   /// By default only `dart:*` libraries are allowed. May be overridden for
   /// testing purposes.
   bool allowPlatformPrivateLibraryAccess(Uri importer, Uri imported) =>
-      imported.scheme != "dart" ||
-      !imported.path.startsWith("_") ||
       importer.scheme == "dart" ||
       (importer.scheme == "package" &&
           importer.path.startsWith("dart_internal/"));
diff --git a/pkg/kernel/lib/text/ast_to_text.dart b/pkg/kernel/lib/text/ast_to_text.dart
index 6a24e52..4f718b9 100644
--- a/pkg/kernel/lib/text/ast_to_text.dart
+++ b/pkg/kernel/lib/text/ast_to_text.dart
@@ -1294,6 +1294,7 @@
     writeAnnotationList(node.annotations);
     writeIndentation();
     writeModifier(node.isAbstract, 'abstract');
+    writeModifier(node.isMacro, 'macro');
     writeWord('class');
     writeWord(getClassName(node));
     writeTypeParameterList(node.typeParameters);
diff --git a/pkg/kernel/lib/text/text_serializer.dart b/pkg/kernel/lib/text/text_serializer.dart
index 2ee98c3..0a38ec2 100644
--- a/pkg/kernel/lib/text/text_serializer.dart
+++ b/pkg/kernel/lib/text/text_serializer.dart
@@ -2601,6 +2601,7 @@
   Class.FlagEliminatedMixin: "eliminated-mixin",
   Class.FlagMixinDeclaration: "mixin-declaration",
   Class.FlagHasConstConstructor: "has-const-constructor",
+  Class.FlagMacro: "macro",
 };
 
 class ClassFlagTagger implements Tagger<int> {
diff --git a/pkg/kernel/lib/type_environment.dart b/pkg/kernel/lib/type_environment.dart
index 5320daf..a67f7ea 100644
--- a/pkg/kernel/lib/type_environment.dart
+++ b/pkg/kernel/lib/type_environment.dart
@@ -26,6 +26,9 @@
     return new HierarchyBasedTypeEnvironment(coreTypes, hierarchy);
   }
 
+  @override
+  ClassHierarchy get hierarchy;
+
   Class get intClass => coreTypes.intClass;
   Class get numClass => coreTypes.numClass;
   Class get functionClass => coreTypes.functionClass;
diff --git a/pkg/nnbd_migration/lib/migration_cli.dart b/pkg/nnbd_migration/lib/migration_cli.dart
index 9a0a6ec..93691b6 100644
--- a/pkg/nnbd_migration/lib/migration_cli.dart
+++ b/pkg/nnbd_migration/lib/migration_cli.dart
@@ -358,6 +358,7 @@
           logger: isVerbose! ? loggerFactory(true) : null);
     } on Object catch (exception) {
       handleArgParsingException(exception);
+      return null;
     }
   }
 
diff --git a/pkg/smith/analysis_options.yaml b/pkg/smith/analysis_options.yaml
index 1a46de2..55af634 100644
--- a/pkg/smith/analysis_options.yaml
+++ b/pkg/smith/analysis_options.yaml
@@ -1,3 +1,3 @@
 analyzer:
-  strong-mode:
-    implicit-casts: false
+  language:
+    strict-casts: true
diff --git a/pkg/smith/lib/builder.dart b/pkg/smith/lib/builder.dart
index ebe550c..6f27730 100644
--- a/pkg/smith/lib/builder.dart
+++ b/pkg/smith/lib/builder.dart
@@ -73,11 +73,12 @@
         throw FormatException("Step tests multiple configurations: $arguments");
       }
     }
+    var environment = map["environment"] as Map<Object?, Object?>?;
     return Step(
         map["name"] as String,
         script,
         arguments,
-        <String, String>{...?map["environment"]},
+        {...?environment?.cast<String, String>()},
         map["fileset"] as String?,
         map["shards"] as int?,
         isTestRunner,
@@ -192,14 +193,17 @@
   var names = <String>{};
   for (var builderConfiguration in builderConfigurations) {
     var meta = builderConfiguration["meta"] as Map? ?? <String, String>{};
-    var builderNames = <String>[...?builderConfiguration["builders"]];
-    var steps = <Map>[...?builderConfiguration["steps"]];
-    for (var builderName in builderNames) {
-      if (!names.add(builderName)) {
-        throw FormatException('Duplicate builder name: "$builderName"');
+    var builderNames = builderConfiguration["builders"] as List<Object?>?;
+    if (builderNames != null) {
+      var steps = ((builderConfiguration["steps"] ?? []) as List<Object?>)
+          .cast<Map<Object?, Object?>>();
+      for (var builderName in builderNames.cast<String>()) {
+        if (!names.add(builderName)) {
+          throw FormatException('Duplicate builder name: "$builderName"');
+        }
+        builders.add(Builder.parse(builderName, steps, configurations,
+            meta["description"] as String?));
       }
-      builders.add(Builder.parse(
-          builderName, steps, configurations, meta["description"] as String?));
     }
   }
   return builders;
diff --git a/pkg/smith/lib/test_matrix.dart b/pkg/smith/lib/test_matrix.dart
index 0af1ca8..a81a0e3 100644
--- a/pkg/smith/lib/test_matrix.dart
+++ b/pkg/smith/lib/test_matrix.dart
@@ -52,9 +52,13 @@
       }
     });
 
-    var builderConfigurations = <Map>[...?json["builder_configurations"]];
+    var builderConfigurations = [
+      ...?(json["builder_configurations"] as List<Object?>?)
+          ?.cast<Map<Object?, Object?>>()
+    ];
     var builders = parseBuilders(builderConfigurations, configurations);
-    var branches = <String>[...?json["branches"]];
+    var branchesValue = json["branches"] as List?;
+    var branches = [...?branchesValue?.cast<String>()];
 
     // Check that each configuration is tested on at most one builder.
     var testedOn = <Configuration, Builder>{};
diff --git a/pkg/telemetry/analysis_options.yaml b/pkg/telemetry/analysis_options.yaml
index 0fcad72..bb2ae44 100644
--- a/pkg/telemetry/analysis_options.yaml
+++ b/pkg/telemetry/analysis_options.yaml
@@ -1,8 +1,8 @@
 include: package:lints/recommended.yaml
 
 analyzer:
-  strong-mode:
-    implicit-casts: false
+  language:
+    strict-casts: true
 linter:
   rules:
     - unawaited_futures
diff --git a/pkg/test_runner/analysis_options.yaml b/pkg/test_runner/analysis_options.yaml
index 406b0a1..e6a5912 100644
--- a/pkg/test_runner/analysis_options.yaml
+++ b/pkg/test_runner/analysis_options.yaml
@@ -1,6 +1,6 @@
 analyzer:
-  strong-mode:
-    implicit-casts: false
+  language:
+    strict-casts: true
 linter:
   rules:
     # TODO: Enable these once the existing violations have been fixed.
diff --git a/pkg/test_runner/lib/src/command_output.dart b/pkg/test_runner/lib/src/command_output.dart
index 579b10e..cc65097 100644
--- a/pkg/test_runner/lib/src/command_output.dart
+++ b/pkg/test_runner/lib/src/command_output.dart
@@ -174,10 +174,12 @@
       var events = jsonDecode(content);
       if (events != null) {
         validate("Message must be a List", events is List);
+        // TODO(srawlins): This will promote `events` in null safety.
+        var eventList = events as List<dynamic>;
 
         var messagesByType = {for (var type in _allowedTypes) type: <String>[]};
 
-        for (var entry in events) {
+        for (var entry in eventList) {
           validate("Entry must be a Map", entry is Map);
 
           var type = entry['type'];
@@ -207,7 +209,7 @@
         }
 
         return BrowserTestJsonResult(
-            _getOutcome(messagesByType), dom, events as List<dynamic>);
+            _getOutcome(messagesByType), dom, eventList);
       }
     } catch (error) {
       // If something goes wrong, we know the content was not in the correct
@@ -684,8 +686,10 @@
   @override
   void describe(TestCase testCase, Progress progress, OutputWriter output) {
     if (invalidJsonStdout != null) {
+      output.subsection("analyzer json parse result");
+      output.write("- parse failed");
       output.subsection("invalid analyzer json");
-      output.write(invalidJsonStdout);
+      super.describe(testCase, progress, output);
       return;
     }
 
diff --git a/pkg/test_runner/lib/src/options.dart b/pkg/test_runner/lib/src/options.dart
index bfe16f6..dccb5f4 100644
--- a/pkg/test_runner/lib/src/options.dart
+++ b/pkg/test_runner/lib/src/options.dart
@@ -896,7 +896,7 @@
       }
 
       var excludeSuites = configuration['exclude_suite'] != null
-          ? configuration['exclude_suite'].split(',')
+          ? (configuration['exclude_suite'] as String).split(',')
           : [];
       for (var exclude in excludeSuites) {
         if ((selectors as List).contains(exclude)) {
diff --git a/pkg/test_runner/lib/src/testing_servers.dart b/pkg/test_runner/lib/src/testing_servers.dart
index 984f83c..ca69031 100644
--- a/pkg/test_runner/lib/src/testing_servers.dart
+++ b/pkg/test_runner/lib/src/testing_servers.dart
@@ -166,6 +166,7 @@
       server.addHandler('/$prefixBuildDir', fileHandler);
       server.addHandler('/$prefixDartDir', fileHandler);
       server.addHandler('/packages', fileHandler);
+      server.addHandler('/upload', _handleUploadRequest);
       _serverList.add(httpServer);
       return server;
     });
@@ -237,6 +238,23 @@
     });
   }
 
+  void _handleUploadRequest(HttpRequest request) async {
+    try {
+      var builder = await request.fold(BytesBuilder(), (var b, var d) {
+        b.add(d);
+        return b;
+      });
+      var data = builder.takeBytes();
+      DebugLogger.info(
+          'Uploaded data: ${String.fromCharCodes(data as Iterable<int>)}');
+      request.response.headers.set("Access-Control-Allow-Origin", "*");
+      request.response.close();
+    } catch (e) {
+      DebugLogger.warning(
+          'HttpServer: error while processing upload request', e);
+    }
+  }
+
   Uri _getFileUriFromRequestUri(Uri request) {
     // Go to the top of the file to see an explanation of the URL path scheme.
     var pathSegments = request.normalizePath().pathSegments;
diff --git a/pkg/vm/lib/kernel_front_end.dart b/pkg/vm/lib/kernel_front_end.dart
index 51ed004..871ee7d 100644
--- a/pkg/vm/lib/kernel_front_end.dart
+++ b/pkg/vm/lib/kernel_front_end.dart
@@ -101,6 +101,9 @@
       help:
           'Enable global type flow analysis and related transformations in AOT mode.',
       defaultsTo: true);
+  args.addFlag('rta',
+      help: 'Use rapid type analysis for faster compilation in AOT mode.',
+      defaultsTo: true);
   args.addFlag('tree-shake-write-only-fields',
       help: 'Enable tree shaking of fields which are only written in AOT mode.',
       defaultsTo: true);
@@ -181,6 +184,7 @@
   final List<String>? fileSystemRoots = options['filesystem-root'];
   final bool aot = options['aot'];
   final bool tfa = options['tfa'];
+  final bool rta = options['rta'];
   final bool linkPlatform = options['link-platform'];
   final bool embedSources = options['embed-sources'];
   final bool enableAsserts = options['enable-asserts'];
@@ -269,6 +273,7 @@
       deleteToStringPackageUris: options['delete-tostring-package-uri'],
       aot: aot,
       useGlobalTypeFlowAnalysis: tfa,
+      useRapidTypeAnalysis: rta,
       environmentDefines: environmentDefines,
       enableAsserts: enableAsserts,
       useProtobufTreeShakerV2: useProtobufTreeShakerV2,
@@ -337,6 +342,7 @@
     List<String> deleteToStringPackageUris: const <String>[],
     bool aot: false,
     bool useGlobalTypeFlowAnalysis: false,
+    bool useRapidTypeAnalysis: true,
     required Map<String, String> environmentDefines,
     bool enableAsserts: true,
     bool useProtobufTreeShakerV2: false,
@@ -376,7 +382,8 @@
     await runGlobalTransformations(target, component, useGlobalTypeFlowAnalysis,
         enableAsserts, useProtobufTreeShakerV2, errorDetector,
         minimalKernel: minimalKernel,
-        treeShakeWriteOnlyFields: treeShakeWriteOnlyFields);
+        treeShakeWriteOnlyFields: treeShakeWriteOnlyFields,
+        useRapidTypeAnalysis: useRapidTypeAnalysis);
 
     if (minimalKernel) {
       // compiledSources is component.uriToSource.keys.
@@ -433,7 +440,8 @@
     bool useProtobufTreeShakerV2,
     ErrorDetector errorDetector,
     {bool minimalKernel: false,
-    bool treeShakeWriteOnlyFields: false}) async {
+    bool treeShakeWriteOnlyFields: false,
+    bool useRapidTypeAnalysis: true}) async {
   if (errorDetector.hasCompilationErrors) return;
 
   final coreTypes = new CoreTypes(component);
@@ -454,7 +462,8 @@
     globalTypeFlow.transformComponent(target, coreTypes, component,
         treeShakeSignatures: !minimalKernel,
         treeShakeWriteOnlyFields: treeShakeWriteOnlyFields,
-        treeShakeProtobufs: useProtobufTreeShakerV2);
+        treeShakeProtobufs: useProtobufTreeShakerV2,
+        useRapidTypeAnalysis: useRapidTypeAnalysis);
   } else {
     devirtualization.transformComponent(coreTypes, component);
     no_dynamic_invocations_annotator.transformComponent(component);
diff --git a/pkg/vm/lib/transformations/ffi/common.dart b/pkg/vm/lib/transformations/ffi/common.dart
index 42235ff..b50d0a2 100644
--- a/pkg/vm/lib/transformations/ffi/common.dart
+++ b/pkg/vm/lib/transformations/ffi/common.dart
@@ -18,6 +18,7 @@
     show TypeEnvironment, SubtypeCheckMode;
 
 import 'abi.dart';
+import 'native_type_cfe.dart';
 
 /// Represents the (instantiated) ffi.NativeType.
 enum NativeType {
@@ -44,7 +45,7 @@
   kBool,
 }
 
-const Set<NativeType> nativeIntTypes = <NativeType>{
+const Set<NativeType> nativeIntTypesFixedSize = <NativeType>{
   NativeType.kInt8,
   NativeType.kInt16,
   NativeType.kInt32,
@@ -53,6 +54,10 @@
   NativeType.kUint16,
   NativeType.kUint32,
   NativeType.kUint64,
+};
+
+const Set<NativeType> nativeIntTypes = <NativeType>{
+  ...nativeIntTypesFixedSize,
   NativeType.kIntptr,
 };
 
@@ -178,11 +183,15 @@
   final Class compoundClass;
   final Class structClass;
   final Class unionClass;
+  final Class abiSpecificIntegerClass;
+  final Class abiSpecificIntegerMappingClass;
   final Class ffiNativeClass;
   final Class nativeFieldWrapperClass1Class;
   final Class ffiStructLayoutClass;
   final Field ffiStructLayoutTypesField;
   final Field ffiStructLayoutPackingField;
+  final Class ffiAbiSpecificMappingClass;
+  final Field ffiAbiSpecificMappingNativeTypesField;
   final Class ffiInlineArrayClass;
   final Field ffiInlineArrayElementTypeField;
   final Field ffiInlineArrayLengthField;
@@ -202,6 +211,12 @@
   final Procedure unionArrayElemAt;
   final Procedure arrayArrayElemAt;
   final Procedure arrayArrayAssignAt;
+  final Procedure abiSpecificIntegerPointerGetValue;
+  final Procedure abiSpecificIntegerPointerSetValue;
+  final Procedure abiSpecificIntegerPointerElemAt;
+  final Procedure abiSpecificIntegerPointerSetElemAt;
+  final Procedure abiSpecificIntegerArrayElemAt;
+  final Procedure abiSpecificIntegerArraySetElemAt;
   final Procedure asFunctionMethod;
   final Procedure asFunctionInternal;
   final Procedure sizeOfMethod;
@@ -228,6 +243,12 @@
   final Map<NativeType, Procedure> storeMethods;
   final Map<NativeType, Procedure> storeUnalignedMethods;
   final Map<NativeType, Procedure> elementAtMethods;
+  final Procedure loadAbiSpecificIntMethod;
+  final Procedure loadAbiSpecificIntAtIndexMethod;
+  final Procedure storeAbiSpecificIntMethod;
+  final Procedure storeAbiSpecificIntAtIndexMethod;
+  final Procedure abiCurrentMethod;
+  final Map<Constant, Abi> constantAbis;
   final Procedure memCopy;
   final Procedure allocationTearoff;
   final Procedure asFunctionTearoff;
@@ -301,6 +322,10 @@
         compoundClass = index.getClass('dart:ffi', '_Compound'),
         structClass = index.getClass('dart:ffi', 'Struct'),
         unionClass = index.getClass('dart:ffi', 'Union'),
+        abiSpecificIntegerClass =
+            index.getClass('dart:ffi', 'AbiSpecificInteger'),
+        abiSpecificIntegerMappingClass =
+            index.getClass('dart:ffi', 'AbiSpecificIntegerMapping'),
         ffiNativeClass = index.getClass('dart:ffi', 'FfiNative'),
         nativeFieldWrapperClass1Class =
             index.getClass('dart:nativewrappers', 'NativeFieldWrapperClass1'),
@@ -309,6 +334,10 @@
             index.getField('dart:ffi', '_FfiStructLayout', 'fieldTypes'),
         ffiStructLayoutPackingField =
             index.getField('dart:ffi', '_FfiStructLayout', 'packing'),
+        ffiAbiSpecificMappingClass =
+            index.getClass('dart:ffi', '_FfiAbiSpecificMapping'),
+        ffiAbiSpecificMappingNativeTypesField =
+            index.getField('dart:ffi', '_FfiAbiSpecificMapping', 'nativeTypes'),
         ffiInlineArrayClass = index.getClass('dart:ffi', '_FfiInlineArray'),
         ffiInlineArrayElementTypeField =
             index.getField('dart:ffi', '_FfiInlineArray', 'elementType'),
@@ -362,6 +391,18 @@
         arrayArrayElemAt = index.getProcedure('dart:ffi', 'ArrayArray', '[]'),
         arrayArrayAssignAt =
             index.getProcedure('dart:ffi', 'ArrayArray', '[]='),
+        abiSpecificIntegerPointerGetValue = index.getProcedure(
+            'dart:ffi', 'AbiSpecificIntegerPointer', 'get:value'),
+        abiSpecificIntegerPointerSetValue = index.getProcedure(
+            'dart:ffi', 'AbiSpecificIntegerPointer', 'set:value'),
+        abiSpecificIntegerPointerElemAt =
+            index.getProcedure('dart:ffi', 'AbiSpecificIntegerPointer', '[]'),
+        abiSpecificIntegerPointerSetElemAt =
+            index.getProcedure('dart:ffi', 'AbiSpecificIntegerPointer', '[]='),
+        abiSpecificIntegerArrayElemAt =
+            index.getProcedure('dart:ffi', 'AbiSpecificIntegerArray', '[]'),
+        abiSpecificIntegerArraySetElemAt =
+            index.getProcedure('dart:ffi', 'AbiSpecificIntegerArray', '[]='),
         asFunctionMethod = index.getProcedure(
             'dart:ffi', 'NativeFunctionPointer', 'asFunction'),
         asFunctionInternal =
@@ -406,6 +447,20 @@
           final name = nativeTypeClassNames[t];
           return index.getTopLevelProcedure('dart:ffi', "_elementAt$name");
         }),
+        loadAbiSpecificIntMethod =
+            index.getTopLevelProcedure('dart:ffi', "_loadAbiSpecificInt"),
+        loadAbiSpecificIntAtIndexMethod = index.getTopLevelProcedure(
+            'dart:ffi', "_loadAbiSpecificIntAtIndex"),
+        storeAbiSpecificIntMethod =
+            index.getTopLevelProcedure('dart:ffi', "_storeAbiSpecificInt"),
+        storeAbiSpecificIntAtIndexMethod = index.getTopLevelProcedure(
+            'dart:ffi', "_storeAbiSpecificIntAtIndex"),
+        abiCurrentMethod = index.getProcedure('dart:ffi', 'Abi', 'current'),
+        constantAbis = abiNames.map((abi, name) => MapEntry(
+            (index.getField('dart:ffi', 'Abi', name).initializer
+                    as ConstantExpression)
+                .constant,
+            abi)),
         memCopy = index.getTopLevelProcedure('dart:ffi', '_memCopy'),
         allocationTearoff = index.getProcedure(
             'dart:ffi', 'AllocatorAlloc', LibraryIndex.tearoffPrefix + 'call'),
@@ -451,6 +506,7 @@
   /// [Uint32]                             -> [int]
   /// [Uint64]                             -> [int]
   /// [IntPtr]                             -> [int]
+  /// T extends [AbiSpecificInteger]       -> [int]
   /// [Double]                             -> [double]
   /// [Float]                              -> [double]
   /// [Bool]                               -> [bool]
@@ -477,6 +533,9 @@
       }
       return nativeType;
     }
+    if (hierarchy.isSubclassOf(nativeClass, abiSpecificIntegerClass)) {
+      return InterfaceType(intClass, Nullability.legacy);
+    }
     if (hierarchy.isSubclassOf(nativeClass, compoundClass)) {
       if (nativeClass == structClass || nativeClass == unionClass) {
         return null;
@@ -773,6 +832,24 @@
     return dimensions;
   }
 
+  bool isAbiSpecificIntegerSubtype(DartType type) {
+    if (type is InvalidType) {
+      return false;
+    }
+    if (type is NullType) {
+      return false;
+    }
+    if (type is InterfaceType) {
+      if (type.classNode == abiSpecificIntegerClass) {
+        return false;
+      }
+    }
+    return env.isSubtypeOf(
+        type,
+        InterfaceType(abiSpecificIntegerClass, Nullability.legacy),
+        SubtypeCheckMode.ignoringNullabilities);
+  }
+
   bool isCompoundSubtype(DartType type) {
     if (type is InvalidType) {
       return false;
@@ -822,6 +899,76 @@
         interfaceTarget: numMultiplication,
         functionType: numMultiplication.getterType as FunctionType);
   }
+
+  Iterable<MapConstant> getAbiSpecificIntegerMappingAnnotations(Class node) {
+    return node.annotations
+        .whereType<ConstantExpression>()
+        .map((e) => e.constant)
+        .whereType<InstanceConstant>()
+        .where((e) => e.classNode == abiSpecificIntegerMappingClass)
+        .map((instanceConstant) =>
+            instanceConstant.fieldValues.values.single as MapConstant);
+  }
+
+  /// Generates an expression performing an Abi specific integer load or store.
+  ///
+  /// If [value] is provided, it is a store, otherwise a load.
+  ///
+  /// Provide either [index], or [offsetInBytes], or none for an offset of 0.
+  ///
+  /// Generates an expression:
+  ///
+  /// ```dart
+  /// _storeAbiSpecificInt(
+  ///   [8, 8, 4][_abi()],
+  ///   typedDataBase,
+  ///   index * [8, 8, 4][_abi()],
+  ///   value,
+  /// )
+  /// ```
+  Expression abiSpecificLoadOrStoreExpression(
+    AbiSpecificNativeTypeCfe nativeTypeCfe, {
+    required Expression typedDataBase,
+    Expression? offsetInBytes,
+    Expression? index,
+    Expression? value,
+    required fileOffset,
+  }) {
+    assert(index == null || offsetInBytes == null);
+    final method = () {
+      if (value != null) {
+        if (index != null) {
+          return storeAbiSpecificIntAtIndexMethod;
+        }
+        return storeAbiSpecificIntMethod;
+      }
+      if (index != null) {
+        return loadAbiSpecificIntAtIndexMethod;
+      }
+      return loadAbiSpecificIntMethod;
+    }();
+
+    final Expression offsetOrIndex = () {
+      if (offsetInBytes != null) {
+        return offsetInBytes;
+      }
+      if (index != null) {
+        return index;
+      }
+      return ConstantExpression(IntConstant(0));
+    }();
+
+    return StaticInvocation(
+      method,
+      Arguments([
+        typedDataBase,
+        offsetOrIndex,
+        if (value != null) value,
+      ], types: [
+        InterfaceType(nativeTypeCfe.clazz, Nullability.nonNullable)
+      ]),
+    )..fileOffset = fileOffset;
+  }
 }
 
 /// Checks if any library depends on dart:ffi.
diff --git a/pkg/vm/lib/transformations/ffi/definitions.dart b/pkg/vm/lib/transformations/ffi/definitions.dart
index fbf2052..fe38da0 100644
--- a/pkg/vm/lib/transformations/ffi/definitions.dart
+++ b/pkg/vm/lib/transformations/ffi/definitions.dart
@@ -4,6 +4,8 @@
 
 import 'package:front_end/src/api_unstable/vm.dart'
     show
+        messageFfiAbiSpecificIntegerInvalid,
+        messageFfiAbiSpecificIntegerMappingInvalid,
         messageFfiPackedAnnotationAlignment,
         messageNonPositiveArrayDimensions,
         templateFfiEmptyStruct,
@@ -248,8 +250,36 @@
     return true;
   }
 
+  bool _isUserAbiSpecificInteger(Class node) =>
+      hierarchy.isSubclassOf(node, abiSpecificIntegerClass) &&
+      node != abiSpecificIntegerClass;
+
   @override
   visitClass(Class node) {
+    if (_isUserAbiSpecificInteger(node)) {
+      final nativeTypeCfe = NativeTypeCfe(
+              this, node.getThisType(coreTypes, Nullability.nonNullable))
+          as AbiSpecificNativeTypeCfe;
+      if (nativeTypeCfe.abiSpecificTypes.length == 0) {
+        // Annotation missing, multiple annotations, or invalid mapping.
+        diagnosticReporter.report(messageFfiAbiSpecificIntegerMappingInvalid,
+            node.fileOffset, node.name.length, node.location!.file);
+      }
+      if (node.typeParameters.length != 0 ||
+          node.procedures.where((Procedure e) => !e.isSynthetic).length != 0 ||
+          node.fields.length != 0 ||
+          node.redirectingFactories.length != 0 ||
+          node.constructors.length != 1 ||
+          !node.constructors.single.isConst) {
+        // We want exactly one constructor, no other members and no type arguments.
+        diagnosticReporter.report(messageFfiAbiSpecificIntegerInvalid,
+            node.fileOffset, node.name.length, node.location!.file);
+      }
+      final IndexedClass? indexedClass =
+          currentLibraryIndex?.lookupIndexedClass(node.name);
+      _addSizeOfField(node, indexedClass, nativeTypeCfe.size);
+      _annotateAbiSpecificTypeWithMapping(node, nativeTypeCfe);
+    }
     if (!_isUserCompound(node)) {
       return node;
     }
@@ -594,8 +624,13 @@
         final nativeTypeAnnos = _getNativeTypeAnnotations(m).toList();
         if (nativeTypeAnnos.length == 1) {
           final clazz = nativeTypeAnnos.first;
-          final nativeType = _getFieldType(clazz)!;
-          type = PrimitiveNativeTypeCfe(nativeType, clazz);
+          if (_isUserAbiSpecificInteger(clazz)) {
+            type = NativeTypeCfe(
+                this, clazz.getThisType(coreTypes, Nullability.nonNullable));
+          } else {
+            final nativeType = _getFieldType(clazz)!;
+            type = PrimitiveNativeTypeCfe(nativeType, clazz);
+          }
         }
       }
 
@@ -791,6 +826,33 @@
         InterfaceType(pragmaClass, Nullability.nonNullable, [])));
   }
 
+  static const vmFfiAbiSpecificIntMapping = 'vm:ffi:abi-specific-mapping';
+
+  void _annotateAbiSpecificTypeWithMapping(
+      Class node, AbiSpecificNativeTypeCfe nativeTypeCfe) {
+    final constants = [
+      for (final abi in Abi.values)
+        nativeTypeCfe.abiSpecificTypes[abi]?.generateConstant(this) ??
+            NullConstant()
+    ];
+    node.addAnnotation(ConstantExpression(
+        InstanceConstant(pragmaClass.reference, [], {
+          pragmaName.fieldReference: StringConstant(vmFfiAbiSpecificIntMapping),
+          pragmaOptions.fieldReference: InstanceConstant(
+            ffiAbiSpecificMappingClass.reference,
+            [],
+            {
+              ffiAbiSpecificMappingNativeTypesField.fieldReference:
+                  ListConstant(
+                InterfaceType(typeClass, Nullability.nullable),
+                constants,
+              ),
+            },
+          )
+        }),
+        InterfaceType(pragmaClass, Nullability.nonNullable, [])));
+  }
+
   void _generateMethodsForField(
       Class node,
       Field field,
@@ -890,7 +952,8 @@
         .map((expr) => expr.constant)
         .whereType<InstanceConstant>()
         .map((constant) => constant.classNode)
-        .where((klass) => _getFieldType(klass) != null);
+        .where((klass) =>
+            _getFieldType(klass) != null || _isUserAbiSpecificInteger(klass));
   }
 
   Iterable<List<int>> _getArraySizeAnnotations(Member node) {
diff --git a/pkg/vm/lib/transformations/ffi/native_type_cfe.dart b/pkg/vm/lib/transformations/ffi/native_type_cfe.dart
index 862d1bd..bb73a94 100644
--- a/pkg/vm/lib/transformations/ffi/native_type_cfe.dart
+++ b/pkg/vm/lib/transformations/ffi/native_type_cfe.dart
@@ -16,7 +16,8 @@
 abstract class NativeTypeCfe {
   factory NativeTypeCfe(FfiTransformer transformer, DartType dartType,
       {List<int>? arrayDimensions,
-      Map<Class, NativeTypeCfe> compoundCache = const {}}) {
+      Map<Class, NativeTypeCfe> compoundCache = const {},
+      alreadyInAbiSpecificType = false}) {
     if (transformer.isPrimitiveType(dartType)) {
       final clazz = (dartType as InterfaceType).classNode;
       final nativeType = transformer.getType(clazz)!;
@@ -48,6 +49,32 @@
       }
       return ArrayNativeTypeCfe.multi(elementCfeType, arrayDimensions);
     }
+    if (transformer.isAbiSpecificIntegerSubtype(dartType)) {
+      final clazz = (dartType as InterfaceType).classNode;
+      final mappingConstants =
+          transformer.getAbiSpecificIntegerMappingAnnotations(clazz);
+      if (alreadyInAbiSpecificType || mappingConstants.length != 1) {
+        // Unsupported mapping.
+        return AbiSpecificNativeTypeCfe({}, clazz);
+      }
+      final mapping =
+          Map.fromEntries(mappingConstants.first.entries.map((e) => MapEntry(
+              transformer.constantAbis[e.key]!,
+              NativeTypeCfe(
+                transformer,
+                (e.value as InstanceConstant).classNode.getThisType(
+                    transformer.coreTypes, Nullability.nonNullable),
+                alreadyInAbiSpecificType: true,
+              ))));
+      for (final value in mapping.values) {
+        if (value is! PrimitiveNativeTypeCfe ||
+            !nativeIntTypesFixedSize.contains(value.nativeType)) {
+          // Unsupported mapping.
+          return AbiSpecificNativeTypeCfe({}, clazz);
+        }
+      }
+      return AbiSpecificNativeTypeCfe(mapping, clazz);
+    }
     throw "Invalid type $dartType";
   }
 
@@ -557,6 +584,66 @@
         ..fileOffset = fileOffset);
 }
 
+class AbiSpecificNativeTypeCfe implements NativeTypeCfe {
+  final Map<Abi, NativeTypeCfe> abiSpecificTypes;
+
+  final Class clazz;
+
+  AbiSpecificNativeTypeCfe(this.abiSpecificTypes, this.clazz);
+
+  @override
+  Map<Abi, int?> get size => abiSpecificTypes
+      .map((abi, nativeTypeCfe) => MapEntry(abi, nativeTypeCfe.size[abi]));
+
+  @override
+  Map<Abi, int?> get alignment => abiSpecificTypes
+      .map((abi, nativeTypeCfe) => MapEntry(abi, nativeTypeCfe.alignment[abi]));
+
+  @override
+  Constant generateConstant(FfiTransformer transformer) =>
+      TypeLiteralConstant(InterfaceType(clazz, Nullability.nonNullable));
+
+  @override
+  ReturnStatement generateGetterStatement(
+    DartType dartType,
+    int fileOffset,
+    Map<Abi, int?> offsets,
+    bool unalignedAccess,
+    FfiTransformer transformer,
+  ) {
+    return ReturnStatement(
+      transformer.abiSpecificLoadOrStoreExpression(
+        this,
+        typedDataBase: transformer.getCompoundTypedDataBaseField(
+            ThisExpression(), fileOffset),
+        offsetInBytes: transformer.runtimeBranchOnLayout(offsets),
+        fileOffset: fileOffset,
+      ),
+    );
+  }
+
+  @override
+  ReturnStatement generateSetterStatement(
+    DartType dartType,
+    int fileOffset,
+    Map<Abi, int?> offsets,
+    bool unalignedAccess,
+    VariableDeclaration argument,
+    FfiTransformer transformer,
+  ) {
+    return ReturnStatement(
+      transformer.abiSpecificLoadOrStoreExpression(
+        this,
+        typedDataBase: transformer.getCompoundTypedDataBaseField(
+            ThisExpression(), fileOffset),
+        offsetInBytes: transformer.runtimeBranchOnLayout(offsets),
+        value: VariableGet(argument),
+        fileOffset: fileOffset,
+      ),
+    );
+  }
+}
+
 extension on int? {
   int? align(int? alignment) =>
       ((this + alignment - 1) ~/ alignment) * alignment;
diff --git a/pkg/vm/lib/transformations/ffi/use_sites.dart b/pkg/vm/lib/transformations/ffi/use_sites.dart
index 69a52e5..d0e44333 100644
--- a/pkg/vm/lib/transformations/ffi/use_sites.dart
+++ b/pkg/vm/lib/transformations/ffi/use_sites.dart
@@ -27,6 +27,7 @@
 import 'package:kernel/type_environment.dart';
 
 import 'abi.dart' show wordSize;
+import 'native_type_cfe.dart';
 import 'common.dart'
     show NativeType, FfiTransformer, nativeTypeSizes, WORD_SIZE, UNKNOWN;
 
@@ -132,6 +133,42 @@
 
     final Member target = node.target;
     try {
+      if (target == abiSpecificIntegerPointerGetValue ||
+          target == abiSpecificIntegerPointerSetValue ||
+          target == abiSpecificIntegerPointerElemAt ||
+          target == abiSpecificIntegerPointerSetElemAt ||
+          target == abiSpecificIntegerArrayElemAt ||
+          target == abiSpecificIntegerArraySetElemAt) {
+        final pointer = node.arguments.positional[0];
+        final pointerType =
+            pointer.getStaticType(_staticTypeContext!) as InterfaceType;
+        _ensureNativeTypeValid(pointerType, pointer,
+            allowCompounds: true, allowInlineArray: true);
+
+        final typeArg = pointerType.typeArguments.single;
+        final nativeTypeCfe =
+            NativeTypeCfe(this, typeArg) as AbiSpecificNativeTypeCfe;
+
+        return abiSpecificLoadOrStoreExpression(
+          nativeTypeCfe,
+          typedDataBase: (target == abiSpecificIntegerArrayElemAt ||
+                  target == abiSpecificIntegerArraySetElemAt)
+              ? getArrayTypedDataBaseField(node.arguments.positional[0])
+              : node.arguments.positional[0],
+          index: (target == abiSpecificIntegerPointerElemAt ||
+                  target == abiSpecificIntegerPointerSetElemAt ||
+                  target == abiSpecificIntegerArrayElemAt ||
+                  target == abiSpecificIntegerArraySetElemAt)
+              ? node.arguments.positional[1]
+              : null,
+          value: (target == abiSpecificIntegerPointerSetValue ||
+                  target == abiSpecificIntegerPointerSetElemAt ||
+                  target == abiSpecificIntegerArraySetElemAt)
+              ? node.arguments.positional.last
+              : null,
+          fileOffset: node.fileOffset,
+        );
+      }
       if (target == structPointerRef ||
           target == structPointerElemAt ||
           target == unionPointerRef ||
@@ -785,13 +822,19 @@
         klass == opaqueClass ||
         klass == structClass ||
         klass == unionClass ||
+        klass == abiSpecificIntegerClass ||
         classNativeTypes[klass] != null) {
       return null;
     }
 
     // The Opaque and Struct classes can be extended, but subclasses
     // cannot be (nor implemented).
-    final onlyDirectExtendsClasses = [opaqueClass, structClass, unionClass];
+    final onlyDirectExtendsClasses = [
+      opaqueClass,
+      structClass,
+      unionClass,
+      abiSpecificIntegerClass,
+    ];
     final superClass = klass.superclass;
     for (final onlyDirectExtendsClass in onlyDirectExtendsClasses) {
       if (hierarchy.isSubtypeOf(klass, onlyDirectExtendsClass)) {
diff --git a/pkg/vm/lib/transformations/type_flow/rta.dart b/pkg/vm/lib/transformations/type_flow/rta.dart
new file mode 100644
index 0000000..df987e1
--- /dev/null
+++ b/pkg/vm/lib/transformations/type_flow/rta.dart
@@ -0,0 +1,528 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+/// Rapid type analysis on kernel AST.
+
+import 'dart:core' hide Type;
+
+import 'package:kernel/ast.dart';
+import 'package:kernel/class_hierarchy.dart' show ClassHierarchy;
+import 'package:kernel/library_index.dart' show LibraryIndex;
+import 'package:kernel/core_types.dart' show CoreTypes;
+
+import 'calls.dart' as calls
+    show Selector, DirectSelector, InterfaceSelector, VirtualSelector;
+import 'native_code.dart'
+    show EntryPointsListener, NativeCodeOracle, PragmaEntryPointsVisitor;
+import 'protobuf_handler.dart' show ProtobufHandler;
+import 'types.dart' show TFClass, Type, ConcreteType;
+import '../pragma.dart' show ConstantPragmaAnnotationParser;
+
+class Selector {
+  final Name name;
+  final bool setter;
+
+  Selector(this.name, this.setter);
+
+  @override
+  int get hashCode => name.hashCode ^ setter.hashCode;
+
+  @override
+  bool operator ==(Object other) =>
+      other is Selector &&
+      this.name == other.name &&
+      this.setter == other.setter;
+}
+
+class ClassInfo extends TFClass {
+  final ClassInfo? superclass;
+  final Set<ClassInfo> supertypes; // All super-types including this.
+  final Set<ClassInfo> subclasses = Set<ClassInfo>();
+  final Set<ClassInfo> subtypes = Set<ClassInfo>();
+
+  final Set<Selector>
+      calledDynamicSelectors; // Selectors called with dynamic and interface calls.
+  final Set<Selector> calledVirtualSelectors;
+
+  bool isAllocated = false;
+
+  late final Map<Name, Member> _dispatchTargetsSetters =
+      _initDispatchTargets(true);
+  late final Map<Name, Member> _dispatchTargetsNonSetters =
+      _initDispatchTargets(false);
+
+  ClassInfo(int id, Class classNode, this.superclass, this.supertypes,
+      this.calledDynamicSelectors, this.calledVirtualSelectors)
+      : super(id, classNode) {
+    supertypes.add(this);
+    for (var sup in supertypes) {
+      sup.subtypes.add(this);
+    }
+    for (ClassInfo? sup = this; sup != null; sup = sup.superclass) {
+      sup.subclasses.add(this);
+    }
+  }
+
+  late final ConcreteType concreteType = ConcreteType(this, null);
+
+  Map<Name, Member> _initDispatchTargets(bool setters) {
+    Map<Name, Member> targets;
+    final superclass = this.superclass;
+    if (superclass != null) {
+      targets = Map.from(setters
+          ? superclass._dispatchTargetsSetters
+          : superclass._dispatchTargetsNonSetters);
+    } else {
+      targets = {};
+    }
+    for (Field f in classNode.fields) {
+      if (!f.isStatic && !f.isAbstract) {
+        if (!setters || f.hasSetter) {
+          targets[f.name] = f;
+        }
+      }
+    }
+    for (Procedure p in classNode.procedures) {
+      if (!p.isStatic && !p.isAbstract) {
+        if (p.isSetter == setters) {
+          targets[p.name] = p;
+        }
+      }
+    }
+    return targets;
+  }
+
+  Member? getDispatchTarget(Selector selector) {
+    return (selector.setter
+        ? _dispatchTargetsSetters
+        : _dispatchTargetsNonSetters)[selector.name];
+  }
+}
+
+class _ClassHierarchyCache {
+  final Map<Class, ClassInfo> classes = <Class, ClassInfo>{};
+  int _classIdCounter = 0;
+
+  _ClassHierarchyCache();
+
+  ClassInfo getClassInfo(Class c) {
+    return classes[c] ??= _createClassInfo(c);
+  }
+
+  ClassInfo _createClassInfo(Class c) {
+    final supertypes = Set<ClassInfo>();
+    final dynSel = Set<Selector>();
+    for (var sup in c.supers) {
+      final supInfo = getClassInfo(sup.classNode);
+      supertypes.addAll(supInfo.supertypes);
+      dynSel.addAll(supInfo.calledDynamicSelectors);
+    }
+    Class? superclassNode = c.superclass;
+    ClassInfo? superclass;
+    final virtSel = Set<Selector>();
+    if (superclassNode != null) {
+      superclass = getClassInfo(superclassNode);
+      virtSel.addAll(superclass.calledVirtualSelectors);
+    }
+    return ClassInfo(
+        ++_classIdCounter, c, superclass, supertypes, dynSel, virtSel);
+  }
+
+  ConcreteType addAllocatedClass(Class cl, RapidTypeAnalysis rta) {
+    assert(!cl.isAbstract);
+    final ClassInfo classInfo = getClassInfo(cl);
+    if (!classInfo.isAllocated) {
+      classInfo.isAllocated = true;
+      for (var sel in classInfo.calledDynamicSelectors) {
+        final member = classInfo.getDispatchTarget(sel);
+        if (member != null) {
+          rta.addMember(member);
+        }
+      }
+      for (var sel in classInfo.calledVirtualSelectors) {
+        final member = classInfo.getDispatchTarget(sel);
+        if (member != null) {
+          rta.addMember(member);
+        }
+      }
+    }
+    return classInfo.concreteType;
+  }
+
+  void addDynamicCall(Selector selector, Class cl, RapidTypeAnalysis rta) {
+    final ClassInfo classInfo = getClassInfo(cl);
+    for (var sub in classInfo.subtypes) {
+      if (sub.calledDynamicSelectors.add(selector) && sub.isAllocated) {
+        final member = sub.getDispatchTarget(selector);
+        if (member != null) {
+          rta.addMember(member);
+        }
+      }
+    }
+  }
+
+  void addVirtualCall(Selector selector, Class cl, RapidTypeAnalysis rta) {
+    final ClassInfo classInfo = getClassInfo(cl);
+    for (var sub in classInfo.subclasses) {
+      if (sub.calledVirtualSelectors.add(selector) && sub.isAllocated) {
+        final member = sub.getDispatchTarget(selector);
+        if (member != null) {
+          rta.addMember(member);
+        }
+      }
+    }
+  }
+}
+
+class RapidTypeAnalysis {
+  final CoreTypes coreTypes;
+  final ClassHierarchy hierarchy;
+  final _ClassHierarchyCache hierarchyCache = _ClassHierarchyCache();
+  final ProtobufHandler? protobufHandler;
+
+  final Set<Member> visited = {};
+  final List<Member> workList = [];
+
+  RapidTypeAnalysis(Component component, this.coreTypes, this.hierarchy,
+      LibraryIndex libraryIndex, this.protobufHandler) {
+    Procedure? main = component.mainMethod;
+    if (main != null) {
+      addMember(main);
+    }
+    final annotationMatcher = ConstantPragmaAnnotationParser(coreTypes);
+    final nativeCodeOracle = NativeCodeOracle(libraryIndex, annotationMatcher);
+    component.accept(PragmaEntryPointsVisitor(
+        _EntryPointsListenerImpl(this), nativeCodeOracle, annotationMatcher));
+    run();
+  }
+
+  List<Class> get allocatedClasses {
+    return <Class>[
+      for (var entry in hierarchyCache.classes.entries)
+        if (entry.value.isAllocated) entry.key
+    ];
+  }
+
+  bool isAllocatedClass(Class cl) =>
+      hierarchyCache.classes[cl]?.isAllocated ?? false;
+
+  ConcreteType addAllocatedClass(Class cl) =>
+      hierarchyCache.addAllocatedClass(cl, this);
+
+  void addMember(Member member) {
+    if (visited.add(member)) {
+      workList.add(member);
+    }
+  }
+
+  void addCall(Class? currentClass, Member? interfaceTarget, Name name,
+      bool isVirtual, bool isSetter) {
+    final Class cl = isVirtual
+        ? currentClass!
+        : (interfaceTarget != null
+            ? interfaceTarget.enclosingClass!
+            : coreTypes.objectClass);
+    final Selector selector = Selector(name, isSetter);
+    if (isVirtual) {
+      hierarchyCache.addVirtualCall(selector, cl, this);
+    } else {
+      hierarchyCache.addDynamicCall(selector, cl, this);
+    }
+  }
+
+  void run() {
+    final memberVisitor = _MemberVisitor(this);
+    while (workList.isNotEmpty || invalidateProtobufFields()) {
+      final member = workList.removeLast();
+      protobufHandler?.beforeSummaryCreation(member);
+      member.accept(memberVisitor);
+    }
+  }
+
+  bool invalidateProtobufFields() {
+    final protobufHandler = this.protobufHandler;
+    if (protobufHandler == null) {
+      return false;
+    }
+    final fields = protobufHandler.getInvalidatedFields();
+    if (fields.isEmpty) {
+      return false;
+    }
+    // Protobuf handler replaced contents of static field initializers.
+    bool invalidated = false;
+    for (var field in fields) {
+      assert(field.isStatic);
+      if (visited.contains(field)) {
+        workList.add(field);
+        invalidated = true;
+      }
+    }
+    return invalidated;
+  }
+}
+
+class _MemberVisitor extends RecursiveVisitor {
+  final RapidTypeAnalysis rta;
+  final _ConstantVisitor _constantVisitor;
+
+  Class? _currentClass;
+  ClassInfo? _superclassInfo;
+
+  _MemberVisitor(this.rta) : _constantVisitor = _ConstantVisitor(rta);
+
+  ClassInfo get superclassInfo => _superclassInfo ??=
+      rta.hierarchyCache.getClassInfo(_currentClass!.superclass!);
+
+  @override
+  void defaultMember(Member node) {
+    _superclassInfo = null;
+    _currentClass = node.enclosingClass;
+    node.visitChildren(this);
+    if (node is Constructor) {
+      // Make sure instance field initializers are visited.
+      for (var f in _currentClass!.members) {
+        if (f is Field && !f.isStatic) {
+          f.initializer?.accept(this);
+        }
+      }
+    }
+    _superclassInfo = null;
+    _currentClass = null;
+  }
+
+  @override
+  void visitConstructorInvocation(ConstructorInvocation node) {
+    rta.addAllocatedClass(node.constructedType.classNode);
+    rta.addMember(node.target);
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitInstanceInvocation(InstanceInvocation node) {
+    rta.addCall(_currentClass, node.interfaceTarget, node.name,
+        node.receiver is ThisExpression, false);
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitDynamicInvocation(DynamicInvocation node) {
+    rta.addCall(null, null, node.name, false, false);
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitEqualsCall(EqualsCall node) {
+    rta.addCall(_currentClass, node.interfaceTarget, node.interfaceTarget.name,
+        node.left is ThisExpression, false);
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitInstanceGet(InstanceGet node) {
+    rta.addCall(_currentClass, node.interfaceTarget, node.name,
+        node.receiver is ThisExpression, false);
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitInstanceTearOff(InstanceTearOff node) {
+    rta.addCall(_currentClass, node.interfaceTarget, node.name,
+        node.receiver is ThisExpression, false);
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitDynamicGet(DynamicGet node) {
+    rta.addCall(null, null, node.name, false, false);
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitInstanceSet(InstanceSet node) {
+    rta.addCall(_currentClass, node.interfaceTarget, node.name,
+        node.receiver is ThisExpression, true);
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitDynamicSet(DynamicSet node) {
+    rta.addCall(null, null, node.name, false, true);
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitSuperMethodInvocation(SuperMethodInvocation node) {
+    final target = superclassInfo.getDispatchTarget(Selector(node.name, false));
+    if (target != null) {
+      rta.addMember(target);
+    }
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitSuperPropertyGet(SuperPropertyGet node) {
+    final target = superclassInfo.getDispatchTarget(Selector(node.name, false));
+    if (target != null) {
+      rta.addMember(target);
+    }
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitSuperPropertySet(SuperPropertySet node) {
+    final target = superclassInfo.getDispatchTarget(Selector(node.name, true));
+    if (target != null) {
+      rta.addMember(target);
+    }
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitStaticGet(StaticGet node) {
+    rta.addMember(node.target);
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitStaticInvocation(StaticInvocation node) {
+    rta.addMember(node.target);
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitStaticSet(StaticSet node) {
+    rta.addMember(node.target);
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitRedirectingInitializer(RedirectingInitializer node) {
+    rta.addMember(node.target);
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitSuperInitializer(SuperInitializer node) {
+    // Re-resolve target due to partial mixin resolution.
+    for (var replacement in _currentClass!.superclass!.constructors) {
+      if (node.target.name == replacement.name) {
+        rta.addMember(replacement);
+        break;
+      }
+    }
+    node.visitChildren(this);
+  }
+
+  @override
+  void visitConstantExpression(ConstantExpression node) {
+    _constantVisitor.visit(node.constant);
+  }
+}
+
+class _ConstantVisitor extends ConstantVisitor<void> {
+  final RapidTypeAnalysis rta;
+  final Set<Constant> visited = {};
+
+  _ConstantVisitor(this.rta);
+
+  void visit(Constant constant) {
+    if (visited.add(constant)) {
+      constant.accept(this);
+    }
+  }
+
+  @override
+  void defaultConstant(Constant node) {}
+
+  @override
+  void visitListConstant(ListConstant constant) {
+    for (final entry in constant.entries) {
+      visit(entry);
+    }
+  }
+
+  @override
+  void visitMapConstant(MapConstant constant) {
+    for (final entry in constant.entries) {
+      visit(entry.key);
+      visit(entry.value);
+    }
+  }
+
+  @override
+  void visitSetConstant(SetConstant constant) {
+    for (final entry in constant.entries) {
+      visit(entry);
+    }
+  }
+
+  @override
+  void visitInstanceConstant(InstanceConstant constant) {
+    rta.addAllocatedClass(constant.classNode);
+    for (var value in constant.fieldValues.values) {
+      visit(value);
+    }
+  }
+
+  void _visitTearOffConstant(TearOffConstant constant) {
+    final Member member = constant.target;
+    rta.addMember(member);
+    if (member is Constructor) {
+      rta.addAllocatedClass(member.enclosingClass);
+    }
+  }
+
+  @override
+  void visitStaticTearOffConstant(StaticTearOffConstant constant) =>
+      _visitTearOffConstant(constant);
+
+  @override
+  void visitConstructorTearOffConstant(ConstructorTearOffConstant constant) =>
+      _visitTearOffConstant(constant);
+
+  @override
+  void visitRedirectingFactoryTearOffConstant(
+          RedirectingFactoryTearOffConstant constant) =>
+      _visitTearOffConstant(constant);
+
+  @override
+  void visitInstantiationConstant(InstantiationConstant constant) {
+    visit(constant.tearOffConstant);
+  }
+}
+
+class _EntryPointsListenerImpl implements EntryPointsListener {
+  final RapidTypeAnalysis rta;
+
+  _EntryPointsListenerImpl(this.rta);
+
+  @override
+  void addFieldUsedInConstant(Field field, Type instance, Type value) {}
+
+  @override
+  void addRawCall(calls.Selector selector) {
+    if (selector is calls.DirectSelector) {
+      rta.addMember(selector.member);
+    } else if (selector is calls.InterfaceSelector) {
+      rta.addCall(selector.member.enclosingClass!, selector.member,
+          selector.name, selector is calls.VirtualSelector, selector.isSetter);
+    } else {
+      throw 'Unexpected selector ${selector.runtimeType} $selector';
+    }
+  }
+
+  @override
+  ConcreteType addAllocatedClass(Class c) => rta.addAllocatedClass(c);
+
+  @override
+  void recordMemberCalledViaInterfaceSelector(Member target) =>
+      throw 'Unsupported operation';
+
+  @override
+  void recordMemberCalledViaThis(Member target) =>
+      throw 'Unsupported operation';
+
+  @override
+  void recordTearOff(Member target) => throw 'Unsupported operation';
+}
diff --git a/pkg/vm/lib/transformations/type_flow/transformer.dart b/pkg/vm/lib/transformations/type_flow/transformer.dart
index 1868a4d..d82925a 100644
--- a/pkg/vm/lib/transformations/type_flow/transformer.dart
+++ b/pkg/vm/lib/transformations/type_flow/transformer.dart
@@ -20,6 +20,7 @@
 import 'calls.dart';
 import 'signature_shaking.dart';
 import 'protobuf_handler.dart' show ProtobufHandler;
+import 'rta.dart' show RapidTypeAnalysis;
 import 'summary.dart';
 import 'table_selector_assigner.dart';
 import 'types.dart';
@@ -44,7 +45,8 @@
     {PragmaAnnotationParser? matcher,
     bool treeShakeSignatures: true,
     bool treeShakeWriteOnlyFields: true,
-    bool treeShakeProtobufs: false}) {
+    bool treeShakeProtobufs: false,
+    bool useRapidTypeAnalysis: true}) {
   void ignoreAmbiguousSupertypes(Class cls, Supertype a, Supertype b) {}
   final hierarchy = new ClassHierarchy(component, coreTypes,
           onAmbiguousSupertypes: ignoreAmbiguousSupertypes)
@@ -58,6 +60,25 @@
       : null;
 
   Statistics.reset();
+
+  CleanupAnnotations(coreTypes, libraryIndex, protobufHandler)
+      .visitComponent(component);
+
+  Stopwatch? rtaStopWatch;
+  RapidTypeAnalysis? rta;
+  if (useRapidTypeAnalysis) {
+    // Rapid type analysis (RTA) is used to quickly calculate
+    // the set of allocated classes to make the subsequent
+    // type flow analysis converge much faster.
+    rtaStopWatch = new Stopwatch()..start();
+    final protobufHandlerRta = treeShakeProtobufs
+        ? ProtobufHandler.forComponent(component, coreTypes)
+        : null;
+    rta = RapidTypeAnalysis(
+        component, coreTypes, hierarchy, libraryIndex, protobufHandlerRta);
+    rtaStopWatch.stop();
+  }
+
   final analysisStopWatch = new Stopwatch()..start();
 
   MoveFieldInitializers().transformComponent(component);
@@ -81,8 +102,11 @@
     typeFlowAnalysis.addRawCall(mainSelector);
   }
 
-  CleanupAnnotations(coreTypes, libraryIndex, protobufHandler)
-      .visitComponent(component);
+  if (useRapidTypeAnalysis) {
+    for (Class c in rta!.allocatedClasses) {
+      typeFlowAnalysis.addAllocatedClass(c);
+    }
+  }
 
   typeFlowAnalysis.process();
 
@@ -119,6 +143,9 @@
 
   transformsStopWatch.stop();
 
+  if (useRapidTypeAnalysis) {
+    statPrint("RTA took ${rtaStopWatch!.elapsedMilliseconds}ms");
+  }
   statPrint("TF analysis took ${analysisStopWatch.elapsedMilliseconds}ms");
   statPrint("TF transforms took ${transformsStopWatch.elapsedMilliseconds}ms");
 
@@ -160,7 +187,7 @@
         if (!_isRedirectingConstructor(c)) c
     ];
 
-    assert(constructors.isNotEmpty);
+    assert(constructors.isNotEmpty || cls.isMixinDeclaration);
 
     // Move field initializers to constructors.
     // Clone AST for all constructors except the first.
@@ -315,13 +342,7 @@
     Constant? constantValue;
     bool isInt = false;
 
-    // Note: the explicit type `bool` is needed because the checked-in version
-    // of the CFE that we use for bootstrapping doesn't yet have constructor
-    // tearoffs enabled, and the fix for bug
-    // https://github.com/dart-lang/language/issues/1785 only takes effect when
-    // constructor tearoffs are enabled.  TODO(paulberry): remove the type after
-    // the bootstrap CFE enables constructor tearoffs.
-    final bool nullable = type is NullableType;
+    final nullable = type is NullableType;
     if (nullable) {
       type = type.baseType;
     }
@@ -985,6 +1006,7 @@
     if (parent is Class) {
       shaker.addClassUsedInType(parent);
     }
+    node.visitChildren(this);
   }
 }
 
diff --git a/pkg/vm/pubspec.yaml b/pkg/vm/pubspec.yaml
index 3ae9534..4086172 100644
--- a/pkg/vm/pubspec.yaml
+++ b/pkg/vm/pubspec.yaml
@@ -4,7 +4,7 @@
 publish_to: none
 
 environment:
-  sdk: '>=2.12.0 <3.0.0'
+  sdk: '>=2.15.0 <3.0.0'
 
 dependencies:
   args: ^2.0.0
diff --git a/pkg/vm/test/transformations/protobuf_aware_treeshaker/treeshaker_test.dart b/pkg/vm/test/transformations/protobuf_aware_treeshaker/treeshaker_test.dart
index 741c2b9..4febdf9 100644
--- a/pkg/vm/test/transformations/protobuf_aware_treeshaker/treeshaker_test.dart
+++ b/pkg/vm/test/transformations/protobuf_aware_treeshaker/treeshaker_test.dart
@@ -92,17 +92,19 @@
   );
 }
 
-main() async {
-  final testCases = Directory(path.join(
-    pkgVmDir,
-    'testcases',
-    'transformations',
-    'type_flow',
-    'transformer',
-    'protobuf_handler',
-    'lib',
-  )).listSync().where((f) => f.path.endsWith('_test.dart'));
-  for (final entry in testCases) {
-    test(entry.path, () => runTestCase(entry.uri));
-  }
+main() {
+  group('protobuf-aware-treeshaker', () {
+    final testCases = Directory(path.join(
+      pkgVmDir,
+      'testcases',
+      'transformations',
+      'type_flow',
+      'transformer',
+      'protobuf_handler',
+      'lib',
+    )).listSync().where((f) => f.path.endsWith('_test.dart'));
+    for (final entry in testCases) {
+      test(entry.path, () => runTestCase(entry.uri));
+    }
+  }, timeout: Timeout.none);
 }
diff --git a/pkg/vm/testcases/transformations/ffi/abi_specific_int.dart b/pkg/vm/testcases/transformations/ffi/abi_specific_int.dart
new file mode 100644
index 0000000..50266bd
--- /dev/null
+++ b/pkg/vm/testcases/transformations/ffi/abi_specific_int.dart
@@ -0,0 +1,106 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:ffi';
+
+@AbiSpecificIntegerMapping({
+  Abi.androidArm: Uint32(),
+  Abi.androidArm64: Uint32(),
+  Abi.androidIA32: Uint32(),
+  Abi.androidX64: Uint32(),
+  Abi.fuchsiaArm64: Uint64(),
+  Abi.fuchsiaX64: Uint32(),
+  Abi.iosArm: Uint32(),
+  Abi.iosArm64: Uint32(),
+  Abi.iosX64: Uint32(),
+  Abi.linuxArm: Uint32(),
+  Abi.linuxArm64: Uint32(),
+  Abi.linuxIA32: Uint32(),
+  Abi.linuxX64: Uint32(),
+  Abi.macosArm64: Uint32(),
+  Abi.macosX64: Uint32(),
+  Abi.windowsArm64: Uint16(),
+  Abi.windowsIA32: Uint16(),
+  Abi.windowsX64: Uint16(),
+})
+class WChar extends AbiSpecificInteger {
+  const WChar();
+}
+
+void main() {
+  testSizeOf();
+  testStoreLoad();
+  testStoreLoadIndexed();
+  testStruct();
+  testInlineArray();
+}
+
+void testSizeOf() {
+  final size = sizeOf<WChar>();
+  print(size);
+}
+
+void testStoreLoad() {
+  final p = noAlloc<WChar>();
+  p.value = 10;
+  print(p.value);
+  noAlloc.free(p);
+}
+
+void testStoreLoadIndexed() {
+  final p = noAlloc<WChar>(2);
+  p[0] = 10;
+  p[1] = 3;
+  print(p[0]);
+  print(p[1]);
+  noAlloc.free(p);
+}
+
+class WCharStruct extends Struct {
+  @WChar()
+  external int a0;
+
+  @WChar()
+  external int a1;
+}
+
+void testStruct() {
+  final p = noAlloc<WCharStruct>();
+  p.ref.a0 = 1;
+  print(p.ref.a0);
+  p.ref.a0 = 2;
+  print(p.ref.a0);
+  noAlloc.free(p);
+}
+
+class WCharArrayStruct extends Struct {
+  @Array(100)
+  external Array<WChar> a0;
+}
+
+void testInlineArray() {
+  final p = noAlloc<WCharArrayStruct>();
+  final array = p.ref.a0;
+  for (int i = 0; i < 100; i++) {
+    array[i] = i;
+  }
+  for (int i = 0; i < 100; i++) {
+    print(array[i]);
+  }
+  noAlloc.free(p);
+}
+
+const noAlloc = _DummyAllocator();
+
+class _DummyAllocator implements Allocator {
+  const _DummyAllocator();
+
+  @override
+  Pointer<T> allocate<T extends NativeType>(int byteCount, {int? alignment}) {
+    return Pointer.fromAddress(0);
+  }
+
+  @override
+  void free(Pointer pointer) {}
+}
diff --git a/pkg/vm/testcases/transformations/ffi/abi_specific_int.dart.expect b/pkg/vm/testcases/transformations/ffi/abi_specific_int.dart.expect
new file mode 100644
index 0000000..d8ba7e5
--- /dev/null
+++ b/pkg/vm/testcases/transformations/ffi/abi_specific_int.dart.expect
@@ -0,0 +1,205 @@
+library #lib /*isNonNullableByDefault*/;
+import self as self;
+import "dart:ffi" as ffi;
+import "dart:core" as core;
+import "dart:typed_data" as typ;
+import "dart:_internal" as _in;
+
+import "dart:ffi";
+
+@#C49
+@#C56
+class WChar extends ffi::AbiSpecificInteger /*hasConstConstructor*/  {
+  const constructor •() → self::WChar
+    : super ffi::AbiSpecificInteger::•()
+    ;
+  @#C59
+  static get #sizeOf() → core::int*
+    return #C61.{core::List::[]}(ffi::_abi()){(core::int) → core::int*};
+}
+@#C66
+class WCharStruct extends ffi::Struct {
+  synthetic constructor •() → self::WCharStruct
+    : super ffi::Struct::•()
+    ;
+  constructor #fromTypedDataBase(core::Object #typedDataBase) → self::WCharStruct
+    : super ffi::Struct::_fromTypedDataBase(#typedDataBase)
+    ;
+  @#C67
+  get a0() → core::int
+    return ffi::_loadAbiSpecificInt<self::WChar>(this.{ffi::_Compound::_typedDataBase}{core::Object}, #C68.{core::List::[]}(ffi::_abi()){(core::int) → core::int*});
+  @#C67
+  set a0(core::int #externalFieldValue) → void
+    return ffi::_storeAbiSpecificInt<self::WChar>(this.{ffi::_Compound::_typedDataBase}{core::Object}, #C68.{core::List::[]}(ffi::_abi()){(core::int) → core::int*}, #externalFieldValue);
+  @#C67
+  get a1() → core::int
+    return ffi::_loadAbiSpecificInt<self::WChar>(this.{ffi::_Compound::_typedDataBase}{core::Object}, #C61.{core::List::[]}(ffi::_abi()){(core::int) → core::int*});
+  @#C67
+  set a1(core::int #externalFieldValue) → void
+    return ffi::_storeAbiSpecificInt<self::WChar>(this.{ffi::_Compound::_typedDataBase}{core::Object}, #C61.{core::List::[]}(ffi::_abi()){(core::int) → core::int*}, #externalFieldValue);
+  @#C59
+  static get #sizeOf() → core::int*
+    return #C70.{core::List::[]}(ffi::_abi()){(core::int) → core::int*};
+}
+@#C75
+class WCharArrayStruct extends ffi::Struct {
+  synthetic constructor •() → self::WCharArrayStruct
+    : super ffi::Struct::•()
+    ;
+  constructor #fromTypedDataBase(core::Object #typedDataBase) → self::WCharArrayStruct
+    : super ffi::Struct::_fromTypedDataBase(#typedDataBase)
+    ;
+  @#C76
+  get a0() → ffi::Array<self::WChar>
+    return new ffi::Array::_<self::WChar>( block {
+      core::Object #typedDataBase = this.{ffi::_Compound::_typedDataBase}{core::Object};
+      core::int #offset = #C68.{core::List::[]}(ffi::_abi()){(core::int) → core::int*};
+    } =>#typedDataBase is ffi::Pointer<dynamic> ?{core::Object} ffi::_fromAddress<self::WChar>(#typedDataBase.{ffi::Pointer::address}{core::int}.{core::num::+}(#offset){(core::num) → core::num}) : let typ::TypedData #typedData = _in::unsafeCast<typ::TypedData>(#typedDataBase) in #typedData.{typ::TypedData::buffer}{typ::ByteBuffer}.{typ::ByteBuffer::asUint8List}(#typedData.{typ::TypedData::offsetInBytes}{core::int}.{core::num::+}(#offset){(core::num) → core::num}, #C80.{core::List::[]}(ffi::_abi()){(core::int) → core::int*}){([core::int, core::int?]) → typ::Uint8List}, #C71, #C81);
+  @#C76
+  set a0(ffi::Array<self::WChar> #externalFieldValue) → void
+    return ffi::_memCopy(this.{ffi::_Compound::_typedDataBase}{core::Object}, #C68.{core::List::[]}(ffi::_abi()){(core::int) → core::int*}, #externalFieldValue.{ffi::Array::_typedDataBase}{core::Object}, #C1, #C80.{core::List::[]}(ffi::_abi()){(core::int) → core::int*});
+  @#C59
+  static get #sizeOf() → core::int*
+    return #C80.{core::List::[]}(ffi::_abi()){(core::int) → core::int*};
+}
+class _DummyAllocator extends core::Object implements ffi::Allocator /*hasConstConstructor*/  {
+  const constructor •() → self::_DummyAllocator
+    : super core::Object::•()
+    ;
+  @#C82
+  method allocate<T extends ffi::NativeType>(core::int byteCount, {core::int? alignment = #C58}) → ffi::Pointer<self::_DummyAllocator::allocate::T> {
+    return ffi::Pointer::fromAddress<self::_DummyAllocator::allocate::T>(0);
+  }
+  @#C82
+  method free(ffi::Pointer<ffi::NativeType> pointer) → void {}
+}
+static const field self::_DummyAllocator noAlloc = #C83;
+static method main() → void {
+  self::testSizeOf();
+  self::testStoreLoad();
+  self::testStoreLoadIndexed();
+  self::testStruct();
+  self::testInlineArray();
+}
+static method testSizeOf() → void {
+  final core::int size = self::WChar::#sizeOf;
+  core::print(size);
+}
+static method testStoreLoad() → void {
+  final ffi::Pointer<self::WChar> p = #C83.{ffi::Allocator::allocate}<self::WChar>(self::WChar::#sizeOf){(core::int, {alignment: core::int?}) → ffi::Pointer<self::WChar>};
+  ffi::_storeAbiSpecificInt<self::WChar>(p, #C1, 10);
+  core::print(ffi::_loadAbiSpecificInt<self::WChar>(p, #C1));
+  #C83.{self::_DummyAllocator::free}(p){(ffi::Pointer<ffi::NativeType>) → void};
+}
+static method testStoreLoadIndexed() → void {
+  final ffi::Pointer<self::WChar> p = #C83.{ffi::Allocator::allocate}<self::WChar>(2.{core::num::*}(self::WChar::#sizeOf){(core::num) → core::num}){(core::int, {alignment: core::int?}) → ffi::Pointer<self::WChar>};
+  ffi::_storeAbiSpecificIntAtIndex<self::WChar>(p, 0, 10);
+  ffi::_storeAbiSpecificIntAtIndex<self::WChar>(p, 1, 3);
+  core::print(ffi::_loadAbiSpecificIntAtIndex<self::WChar>(p, 0));
+  core::print(ffi::_loadAbiSpecificIntAtIndex<self::WChar>(p, 1));
+  #C83.{self::_DummyAllocator::free}(p){(ffi::Pointer<ffi::NativeType>) → void};
+}
+static method testStruct() → void {
+  final ffi::Pointer<self::WCharStruct> p = #C83.{ffi::Allocator::allocate}<self::WCharStruct>(self::WCharStruct::#sizeOf){(core::int, {alignment: core::int?}) → ffi::Pointer<self::WCharStruct>};
+  new self::WCharStruct::#fromTypedDataBase(p!).{self::WCharStruct::a0} = 1;
+  core::print(new self::WCharStruct::#fromTypedDataBase(p!).{self::WCharStruct::a0}{core::int});
+  new self::WCharStruct::#fromTypedDataBase(p!).{self::WCharStruct::a0} = 2;
+  core::print(new self::WCharStruct::#fromTypedDataBase(p!).{self::WCharStruct::a0}{core::int});
+  #C83.{self::_DummyAllocator::free}(p){(ffi::Pointer<ffi::NativeType>) → void};
+}
+static method testInlineArray() → void {
+  final ffi::Pointer<self::WCharArrayStruct> p = #C83.{ffi::Allocator::allocate}<self::WCharArrayStruct>(self::WCharArrayStruct::#sizeOf){(core::int, {alignment: core::int?}) → ffi::Pointer<self::WCharArrayStruct>};
+  final ffi::Array<self::WChar> array = new self::WCharArrayStruct::#fromTypedDataBase(p!).{self::WCharArrayStruct::a0}{ffi::Array<self::WChar>};
+  for (core::int i = 0; i.{core::num::<}(100){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+    ffi::_storeAbiSpecificIntAtIndex<self::WChar>(array.{ffi::Array::_typedDataBase}{core::Object}, i, i);
+  }
+  for (core::int i = 0; i.{core::num::<}(100){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+    core::print(ffi::_loadAbiSpecificIntAtIndex<self::WChar>(array.{ffi::Array::_typedDataBase}{core::Object}, i));
+  }
+  #C83.{self::_DummyAllocator::free}(p){(ffi::Pointer<ffi::NativeType>) → void};
+}
+constants  {
+  #C1 = 0
+  #C2 = "android"
+  #C3 = ffi::_OS {index:#C1, _name:#C2}
+  #C4 = "arm"
+  #C5 = ffi::_Architecture {index:#C1, _name:#C4}
+  #C6 = ffi::Abi {_os:#C3, _architecture:#C5}
+  #C7 = ffi::Uint32 {}
+  #C8 = 1
+  #C9 = "arm64"
+  #C10 = ffi::_Architecture {index:#C8, _name:#C9}
+  #C11 = ffi::Abi {_os:#C3, _architecture:#C10}
+  #C12 = 2
+  #C13 = "ia32"
+  #C14 = ffi::_Architecture {index:#C12, _name:#C13}
+  #C15 = ffi::Abi {_os:#C3, _architecture:#C14}
+  #C16 = 3
+  #C17 = "x64"
+  #C18 = ffi::_Architecture {index:#C16, _name:#C17}
+  #C19 = ffi::Abi {_os:#C3, _architecture:#C18}
+  #C20 = "fuchsia"
+  #C21 = ffi::_OS {index:#C8, _name:#C20}
+  #C22 = ffi::Abi {_os:#C21, _architecture:#C10}
+  #C23 = ffi::Uint64 {}
+  #C24 = ffi::Abi {_os:#C21, _architecture:#C18}
+  #C25 = "ios"
+  #C26 = ffi::_OS {index:#C12, _name:#C25}
+  #C27 = ffi::Abi {_os:#C26, _architecture:#C5}
+  #C28 = ffi::Abi {_os:#C26, _architecture:#C10}
+  #C29 = ffi::Abi {_os:#C26, _architecture:#C18}
+  #C30 = "linux"
+  #C31 = ffi::_OS {index:#C16, _name:#C30}
+  #C32 = ffi::Abi {_os:#C31, _architecture:#C5}
+  #C33 = ffi::Abi {_os:#C31, _architecture:#C10}
+  #C34 = ffi::Abi {_os:#C31, _architecture:#C14}
+  #C35 = ffi::Abi {_os:#C31, _architecture:#C18}
+  #C36 = 4
+  #C37 = "macos"
+  #C38 = ffi::_OS {index:#C36, _name:#C37}
+  #C39 = ffi::Abi {_os:#C38, _architecture:#C10}
+  #C40 = ffi::Abi {_os:#C38, _architecture:#C18}
+  #C41 = 5
+  #C42 = "windows"
+  #C43 = ffi::_OS {index:#C41, _name:#C42}
+  #C44 = ffi::Abi {_os:#C43, _architecture:#C10}
+  #C45 = ffi::Uint16 {}
+  #C46 = ffi::Abi {_os:#C43, _architecture:#C14}
+  #C47 = ffi::Abi {_os:#C43, _architecture:#C18}
+  #C48 = <ffi::Abi*, ffi::NativeType*>{#C6:#C7, #C11:#C7, #C15:#C7, #C19:#C7, #C22:#C23, #C24:#C7, #C27:#C7, #C28:#C7, #C29:#C7, #C32:#C7, #C33:#C7, #C34:#C7, #C35:#C7, #C39:#C7, #C40:#C7, #C44:#C45, #C46:#C45, #C47:#C45)
+  #C49 = ffi::AbiSpecificIntegerMapping {mapping:#C48}
+  #C50 = "vm:ffi:abi-specific-mapping"
+  #C51 = TypeLiteralConstant(ffi::Uint32)
+  #C52 = TypeLiteralConstant(ffi::Uint64)
+  #C53 = TypeLiteralConstant(ffi::Uint16)
+  #C54 = <core::Type?>[#C51, #C51, #C51, #C51, #C52, #C51, #C51, #C51, #C51, #C51, #C51, #C51, #C51, #C51, #C51, #C53, #C53, #C53]
+  #C55 = ffi::_FfiAbiSpecificMapping {nativeTypes:#C54}
+  #C56 = core::pragma {name:#C50, options:#C55}
+  #C57 = "vm:prefer-inline"
+  #C58 = null
+  #C59 = core::pragma {name:#C57, options:#C58}
+  #C60 = 8
+  #C61 = <core::int*>[#C36, #C36, #C36, #C36, #C60, #C36, #C36, #C36, #C36, #C36, #C36, #C36, #C36, #C36, #C36, #C12, #C12, #C12]
+  #C62 = "vm:ffi:struct-fields"
+  #C63 = TypeLiteralConstant(self::WChar)
+  #C64 = <core::Type>[#C63, #C63]
+  #C65 = ffi::_FfiStructLayout {fieldTypes:#C64, packing:#C58}
+  #C66 = core::pragma {name:#C62, options:#C65}
+  #C67 = self::WChar {}
+  #C68 = <core::int*>[#C1, #C1, #C1, #C1, #C1, #C1, #C1, #C1, #C1, #C1, #C1, #C1, #C1, #C1, #C1, #C1, #C1, #C1]
+  #C69 = 16
+  #C70 = <core::int*>[#C60, #C60, #C60, #C60, #C69, #C60, #C60, #C60, #C60, #C60, #C60, #C60, #C60, #C60, #C60, #C36, #C36, #C36]
+  #C71 = 100
+  #C72 = ffi::_FfiInlineArray {elementType:#C63, length:#C71}
+  #C73 = <core::Type>[#C72]
+  #C74 = ffi::_FfiStructLayout {fieldTypes:#C73, packing:#C58}
+  #C75 = core::pragma {name:#C62, options:#C74}
+  #C76 = ffi::_ArraySize<ffi::NativeType*> {dimension1:#C71, dimension2:#C58, dimension3:#C58, dimension4:#C58, dimension5:#C58, dimensions:#C58}
+  #C77 = 400
+  #C78 = 800
+  #C79 = 200
+  #C80 = <core::int*>[#C77, #C77, #C77, #C77, #C78, #C77, #C77, #C77, #C77, #C77, #C77, #C77, #C77, #C77, #C77, #C79, #C79, #C79]
+  #C81 = <core::int*>[]
+  #C82 = core::_Override {}
+  #C83 = self::_DummyAllocator {}
+}
diff --git a/pkg/vm/testcases/transformations/ffi/abi_specific_int_incomplete.dart b/pkg/vm/testcases/transformations/ffi/abi_specific_int_incomplete.dart
new file mode 100644
index 0000000..b9759e0
--- /dev/null
+++ b/pkg/vm/testcases/transformations/ffi/abi_specific_int_incomplete.dart
@@ -0,0 +1,92 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:ffi';
+
+@AbiSpecificIntegerMapping({
+  Abi.linuxArm: Uint32(),
+  Abi.linuxArm64: Uint32(),
+  Abi.linuxIA32: Uint32(),
+  Abi.linuxX64: Uint32(),
+})
+class Incomplete extends AbiSpecificInteger {
+  const Incomplete();
+}
+
+void main() {
+  testSizeOf();
+  testStoreLoad();
+  testStoreLoadIndexed();
+  testStruct();
+  testInlineArray();
+}
+
+void testSizeOf() {
+  final size = sizeOf<Incomplete>();
+  print(size);
+}
+
+void testStoreLoad() {
+  final p = noAlloc<Incomplete>();
+  p.value = 10;
+  print(p.value);
+  noAlloc.free(p);
+}
+
+void testStoreLoadIndexed() {
+  final p = noAlloc<Incomplete>(2);
+  p[0] = 10;
+  p[1] = 3;
+  print(p[0]);
+  print(p[1]);
+  noAlloc.free(p);
+}
+
+class IncompleteStruct extends Struct {
+  @Incomplete()
+  external int a0;
+
+  @Incomplete()
+  external int a1;
+}
+
+void testStruct() {
+  final p = noAlloc<IncompleteStruct>();
+  p.ref.a0 = 1;
+  print(p.ref.a0);
+  p.ref.a0 = 2;
+  print(p.ref.a0);
+  noAlloc.free(p);
+}
+
+class IncompleteArrayStruct extends Struct {
+  @Array(100)
+  external Array<Incomplete> a0;
+}
+
+void testInlineArray() {
+  final p = noAlloc<IncompleteArrayStruct>();
+  final array = p.ref.a0;
+  for (int i = 0; i < 100; i++) {
+    array[i] = i;
+  }
+  for (int i = 0; i < 100; i++) {
+    print(array[i]);
+  }
+  noAlloc.free(p);
+}
+
+const noAlloc = _DummyAllocator();
+
+class _DummyAllocator implements Allocator {
+  const _DummyAllocator();
+
+  @override
+  Pointer<T> allocate<T extends NativeType>(int byteCount, {int? alignment}) {
+    return Pointer.fromAddress(0);
+  }
+
+  @override
+  void free(Pointer pointer) {}
+}
diff --git a/pkg/vm/testcases/transformations/ffi/abi_specific_int_incomplete.dart.expect b/pkg/vm/testcases/transformations/ffi/abi_specific_int_incomplete.dart.expect
new file mode 100644
index 0000000..2acfbf6
--- /dev/null
+++ b/pkg/vm/testcases/transformations/ffi/abi_specific_int_incomplete.dart.expect
@@ -0,0 +1,173 @@
+library #lib /*isNonNullableByDefault*/;
+import self as self;
+import "dart:ffi" as ffi;
+import "dart:core" as core;
+import "dart:typed_data" as typ;
+import "dart:_internal" as _in;
+
+import "dart:ffi";
+
+@#C21
+@#C27
+class Incomplete extends ffi::AbiSpecificInteger /*hasConstConstructor*/  {
+  const constructor •() → self::Incomplete
+    : super ffi::AbiSpecificInteger::•()
+    ;
+  @#C29
+  static get #sizeOf() → core::int*
+    return ffi::_checkAbiSpecificIntegerMapping<core::int>(#C31.{core::List::[]}(ffi::_abi()){(core::int) → core::int*});
+}
+@#C36
+class IncompleteStruct extends ffi::Struct {
+  synthetic constructor •() → self::IncompleteStruct
+    : super ffi::Struct::•()
+    ;
+  constructor #fromTypedDataBase(core::Object #typedDataBase) → self::IncompleteStruct
+    : super ffi::Struct::_fromTypedDataBase(#typedDataBase)
+    ;
+  @#C37
+  get a0() → core::int
+    return ffi::_loadAbiSpecificInt<self::Incomplete>(this.{ffi::_Compound::_typedDataBase}{core::Object}, #C38.{core::List::[]}(ffi::_abi()){(core::int) → core::int*});
+  @#C37
+  set a0(core::int #externalFieldValue) → void
+    return ffi::_storeAbiSpecificInt<self::Incomplete>(this.{ffi::_Compound::_typedDataBase}{core::Object}, #C38.{core::List::[]}(ffi::_abi()){(core::int) → core::int*}, #externalFieldValue);
+  @#C37
+  get a1() → core::int
+    return ffi::_loadAbiSpecificInt<self::Incomplete>(this.{ffi::_Compound::_typedDataBase}{core::Object}, ffi::_checkAbiSpecificIntegerMapping<core::int>(#C31.{core::List::[]}(ffi::_abi()){(core::int) → core::int*}));
+  @#C37
+  set a1(core::int #externalFieldValue) → void
+    return ffi::_storeAbiSpecificInt<self::Incomplete>(this.{ffi::_Compound::_typedDataBase}{core::Object}, ffi::_checkAbiSpecificIntegerMapping<core::int>(#C31.{core::List::[]}(ffi::_abi()){(core::int) → core::int*}), #externalFieldValue);
+  @#C29
+  static get #sizeOf() → core::int*
+    return ffi::_checkAbiSpecificIntegerMapping<core::int>(#C40.{core::List::[]}(ffi::_abi()){(core::int) → core::int*});
+}
+@#C45
+class IncompleteArrayStruct extends ffi::Struct {
+  synthetic constructor •() → self::IncompleteArrayStruct
+    : super ffi::Struct::•()
+    ;
+  constructor #fromTypedDataBase(core::Object #typedDataBase) → self::IncompleteArrayStruct
+    : super ffi::Struct::_fromTypedDataBase(#typedDataBase)
+    ;
+  @#C46
+  get a0() → ffi::Array<self::Incomplete>
+    return new ffi::Array::_<self::Incomplete>( block {
+      core::Object #typedDataBase = this.{ffi::_Compound::_typedDataBase}{core::Object};
+      core::int #offset = #C38.{core::List::[]}(ffi::_abi()){(core::int) → core::int*};
+    } =>#typedDataBase is ffi::Pointer<dynamic> ?{core::Object} ffi::_fromAddress<self::Incomplete>(#typedDataBase.{ffi::Pointer::address}{core::int}.{core::num::+}(#offset){(core::num) → core::num}) : let typ::TypedData #typedData = _in::unsafeCast<typ::TypedData>(#typedDataBase) in #typedData.{typ::TypedData::buffer}{typ::ByteBuffer}.{typ::ByteBuffer::asUint8List}(#typedData.{typ::TypedData::offsetInBytes}{core::int}.{core::num::+}(#offset){(core::num) → core::num}, ffi::_checkAbiSpecificIntegerMapping<core::int>(#C48.{core::List::[]}(ffi::_abi()){(core::int) → core::int*})){([core::int, core::int?]) → typ::Uint8List}, #C41, #C49);
+  @#C46
+  set a0(ffi::Array<self::Incomplete> #externalFieldValue) → void
+    return ffi::_memCopy(this.{ffi::_Compound::_typedDataBase}{core::Object}, #C38.{core::List::[]}(ffi::_abi()){(core::int) → core::int*}, #externalFieldValue.{ffi::Array::_typedDataBase}{core::Object}, #C4, ffi::_checkAbiSpecificIntegerMapping<core::int>(#C48.{core::List::[]}(ffi::_abi()){(core::int) → core::int*}));
+  @#C29
+  static get #sizeOf() → core::int*
+    return ffi::_checkAbiSpecificIntegerMapping<core::int>(#C48.{core::List::[]}(ffi::_abi()){(core::int) → core::int*});
+}
+class _DummyAllocator extends core::Object implements ffi::Allocator /*hasConstConstructor*/  {
+  const constructor •() → self::_DummyAllocator
+    : super core::Object::•()
+    ;
+  @#C50
+  method allocate<T extends ffi::NativeType>(core::int byteCount, {core::int? alignment = #C23}) → ffi::Pointer<self::_DummyAllocator::allocate::T> {
+    return ffi::Pointer::fromAddress<self::_DummyAllocator::allocate::T>(0);
+  }
+  @#C50
+  method free(ffi::Pointer<ffi::NativeType> pointer) → void {}
+}
+static const field self::_DummyAllocator noAlloc = #C51;
+static method main() → void {
+  self::testSizeOf();
+  self::testStoreLoad();
+  self::testStoreLoadIndexed();
+  self::testStruct();
+  self::testInlineArray();
+}
+static method testSizeOf() → void {
+  final core::int size = self::Incomplete::#sizeOf;
+  core::print(size);
+}
+static method testStoreLoad() → void {
+  final ffi::Pointer<self::Incomplete> p = #C51.{ffi::Allocator::allocate}<self::Incomplete>(self::Incomplete::#sizeOf){(core::int, {alignment: core::int?}) → ffi::Pointer<self::Incomplete>};
+  ffi::_storeAbiSpecificInt<self::Incomplete>(p, #C4, 10);
+  core::print(ffi::_loadAbiSpecificInt<self::Incomplete>(p, #C4));
+  #C51.{self::_DummyAllocator::free}(p){(ffi::Pointer<ffi::NativeType>) → void};
+}
+static method testStoreLoadIndexed() → void {
+  final ffi::Pointer<self::Incomplete> p = #C51.{ffi::Allocator::allocate}<self::Incomplete>(2.{core::num::*}(self::Incomplete::#sizeOf){(core::num) → core::num}){(core::int, {alignment: core::int?}) → ffi::Pointer<self::Incomplete>};
+  ffi::_storeAbiSpecificIntAtIndex<self::Incomplete>(p, 0, 10);
+  ffi::_storeAbiSpecificIntAtIndex<self::Incomplete>(p, 1, 3);
+  core::print(ffi::_loadAbiSpecificIntAtIndex<self::Incomplete>(p, 0));
+  core::print(ffi::_loadAbiSpecificIntAtIndex<self::Incomplete>(p, 1));
+  #C51.{self::_DummyAllocator::free}(p){(ffi::Pointer<ffi::NativeType>) → void};
+}
+static method testStruct() → void {
+  final ffi::Pointer<self::IncompleteStruct> p = #C51.{ffi::Allocator::allocate}<self::IncompleteStruct>(self::IncompleteStruct::#sizeOf){(core::int, {alignment: core::int?}) → ffi::Pointer<self::IncompleteStruct>};
+  new self::IncompleteStruct::#fromTypedDataBase(p!).{self::IncompleteStruct::a0} = 1;
+  core::print(new self::IncompleteStruct::#fromTypedDataBase(p!).{self::IncompleteStruct::a0}{core::int});
+  new self::IncompleteStruct::#fromTypedDataBase(p!).{self::IncompleteStruct::a0} = 2;
+  core::print(new self::IncompleteStruct::#fromTypedDataBase(p!).{self::IncompleteStruct::a0}{core::int});
+  #C51.{self::_DummyAllocator::free}(p){(ffi::Pointer<ffi::NativeType>) → void};
+}
+static method testInlineArray() → void {
+  final ffi::Pointer<self::IncompleteArrayStruct> p = #C51.{ffi::Allocator::allocate}<self::IncompleteArrayStruct>(self::IncompleteArrayStruct::#sizeOf){(core::int, {alignment: core::int?}) → ffi::Pointer<self::IncompleteArrayStruct>};
+  final ffi::Array<self::Incomplete> array = new self::IncompleteArrayStruct::#fromTypedDataBase(p!).{self::IncompleteArrayStruct::a0}{ffi::Array<self::Incomplete>};
+  for (core::int i = 0; i.{core::num::<}(100){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+    ffi::_storeAbiSpecificIntAtIndex<self::Incomplete>(array.{ffi::Array::_typedDataBase}{core::Object}, i, i);
+  }
+  for (core::int i = 0; i.{core::num::<}(100){(core::num) → core::bool}; i = i.{core::num::+}(1){(core::num) → core::int}) {
+    core::print(ffi::_loadAbiSpecificIntAtIndex<self::Incomplete>(array.{ffi::Array::_typedDataBase}{core::Object}, i));
+  }
+  #C51.{self::_DummyAllocator::free}(p){(ffi::Pointer<ffi::NativeType>) → void};
+}
+constants  {
+  #C1 = 3
+  #C2 = "linux"
+  #C3 = ffi::_OS {index:#C1, _name:#C2}
+  #C4 = 0
+  #C5 = "arm"
+  #C6 = ffi::_Architecture {index:#C4, _name:#C5}
+  #C7 = ffi::Abi {_os:#C3, _architecture:#C6}
+  #C8 = ffi::Uint32 {}
+  #C9 = 1
+  #C10 = "arm64"
+  #C11 = ffi::_Architecture {index:#C9, _name:#C10}
+  #C12 = ffi::Abi {_os:#C3, _architecture:#C11}
+  #C13 = 2
+  #C14 = "ia32"
+  #C15 = ffi::_Architecture {index:#C13, _name:#C14}
+  #C16 = ffi::Abi {_os:#C3, _architecture:#C15}
+  #C17 = "x64"
+  #C18 = ffi::_Architecture {index:#C1, _name:#C17}
+  #C19 = ffi::Abi {_os:#C3, _architecture:#C18}
+  #C20 = <ffi::Abi*, ffi::NativeType*>{#C7:#C8, #C12:#C8, #C16:#C8, #C19:#C8)
+  #C21 = ffi::AbiSpecificIntegerMapping {mapping:#C20}
+  #C22 = "vm:ffi:abi-specific-mapping"
+  #C23 = null
+  #C24 = TypeLiteralConstant(ffi::Uint32)
+  #C25 = <core::Type?>[#C23, #C23, #C23, #C23, #C23, #C23, #C23, #C23, #C23, #C24, #C24, #C24, #C24, #C23, #C23, #C23, #C23, #C23]
+  #C26 = ffi::_FfiAbiSpecificMapping {nativeTypes:#C25}
+  #C27 = core::pragma {name:#C22, options:#C26}
+  #C28 = "vm:prefer-inline"
+  #C29 = core::pragma {name:#C28, options:#C23}
+  #C30 = 4
+  #C31 = <core::int*>[#C23, #C23, #C23, #C23, #C23, #C23, #C23, #C23, #C23, #C30, #C30, #C30, #C30, #C23, #C23, #C23, #C23, #C23]
+  #C32 = "vm:ffi:struct-fields"
+  #C33 = TypeLiteralConstant(self::Incomplete)
+  #C34 = <core::Type>[#C33, #C33]
+  #C35 = ffi::_FfiStructLayout {fieldTypes:#C34, packing:#C23}
+  #C36 = core::pragma {name:#C32, options:#C35}
+  #C37 = self::Incomplete {}
+  #C38 = <core::int*>[#C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4, #C4]
+  #C39 = 8
+  #C40 = <core::int*>[#C23, #C23, #C23, #C23, #C23, #C23, #C23, #C23, #C23, #C39, #C39, #C39, #C39, #C23, #C23, #C23, #C23, #C23]
+  #C41 = 100
+  #C42 = ffi::_FfiInlineArray {elementType:#C33, length:#C41}
+  #C43 = <core::Type>[#C42]
+  #C44 = ffi::_FfiStructLayout {fieldTypes:#C43, packing:#C23}
+  #C45 = core::pragma {name:#C32, options:#C44}
+  #C46 = ffi::_ArraySize<ffi::NativeType*> {dimension1:#C41, dimension2:#C23, dimension3:#C23, dimension4:#C23, dimension5:#C23, dimensions:#C23}
+  #C47 = 400
+  #C48 = <core::int*>[#C23, #C23, #C23, #C23, #C23, #C23, #C23, #C23, #C23, #C47, #C47, #C47, #C47, #C23, #C23, #C23, #C23, #C23]
+  #C49 = <core::int*>[]
+  #C50 = core::_Override {}
+  #C51 = self::_DummyAllocator {}
+}
diff --git a/pkg/vm/testcases/transformations/type_flow/transformer/enum_from_lib_used_as_type.dart.expect b/pkg/vm/testcases/transformations/type_flow/transformer/enum_from_lib_used_as_type.dart.expect
index db77666..aca8022 100644
--- a/pkg/vm/testcases/transformations/type_flow/transformer/enum_from_lib_used_as_type.dart.expect
+++ b/pkg/vm/testcases/transformations/type_flow/transformer/enum_from_lib_used_as_type.dart.expect
@@ -22,6 +22,6 @@
   synthetic constructor •() → self::Class
     : super core::Object::•()
     ;
-[@vm.procedure-attributes.metadata=methodOrSetterCalledDynamically:false,getterCalledDynamically:false,hasThisUses:false,hasTearOffUses:false,methodOrSetterSelectorId:3254,getterSelectorId:3255]  method method([@vm.inferred-type.metadata=dart.core::Null? (value: null)] self::Enum e) → core::int
+[@vm.procedure-attributes.metadata=methodOrSetterCalledDynamically:false,getterCalledDynamically:false,hasThisUses:false,hasTearOffUses:false,methodOrSetterSelectorId:3380,getterSelectorId:3381]  method method([@vm.inferred-type.metadata=dart.core::Null? (value: null)] self::Enum e) → core::int
     return [@vm.inferred-type.metadata=!] e.{core::_Enum::index}{core::int};
 }
diff --git a/pkg/vm/testcases/transformations/type_flow/transformer/mixin_with_field_test.dart b/pkg/vm/testcases/transformations/type_flow/transformer/mixin_with_field_test.dart
new file mode 100644
index 0000000..bca77d0
--- /dev/null
+++ b/pkg/vm/testcases/transformations/type_flow/transformer/mixin_with_field_test.dart
@@ -0,0 +1,15 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// Regression test for dartbug.com/47822
+
+mixin M {
+  int x = (() => 7)();
+}
+
+class C with M {}
+
+main() {
+  print(C().x);
+}
diff --git a/pkg/vm/testcases/transformations/type_flow/transformer/mixin_with_field_test.dart.expect b/pkg/vm/testcases/transformations/type_flow/transformer/mixin_with_field_test.dart.expect
new file mode 100644
index 0000000..14d7ff0
--- /dev/null
+++ b/pkg/vm/testcases/transformations/type_flow/transformer/mixin_with_field_test.dart.expect
@@ -0,0 +1,20 @@
+library #lib /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class M extends core::Object /*isMixinDeclaration*/  {
+}
+abstract class _C&Object&M extends core::Object implements self::M /*isAnonymousMixin,isEliminatedMixin*/  {
+[@vm.inferred-type.metadata=int?] [@vm.procedure-attributes.metadata=methodOrSetterCalledDynamically:false,getterCalledDynamically:false,hasThisUses:false,hasNonThisUses:false,hasTearOffUses:false,methodOrSetterSelectorId:1,getterSelectorId:2]  field core::int x;
+  synthetic constructor •() → self::_C&Object&M
+    : self::_C&Object&M::x = (() → core::int => 7)(){() → core::int}, super core::Object::•()
+    ;
+}
+class C extends self::_C&Object&M {
+  synthetic constructor •() → self::C
+    : super self::_C&Object&M::•()
+    ;
+}
+static method main() → dynamic {
+  core::print([@vm.direct-call.metadata=#lib::_C&Object&M.x] [@vm.inferred-type.metadata=int?] new self::C::•().{self::_C&Object&M::x}{core::int});
+}
diff --git a/pkg/vm/testcases/transformations/type_flow/transformer/no_such_method.dart.expect b/pkg/vm/testcases/transformations/type_flow/transformer/no_such_method.dart.expect
index 1212909..f5fb218 100644
--- a/pkg/vm/testcases/transformations/type_flow/transformer/no_such_method.dart.expect
+++ b/pkg/vm/testcases/transformations/type_flow/transformer/no_such_method.dart.expect
@@ -13,6 +13,8 @@
     : super core::Object::•()
     ;
 }
+class T3 extends core::Object {
+}
 class T4 extends core::Object {
   synthetic constructor •() → self::T4
     : super core::Object::•()
diff --git a/pkg/vm/testcases/transformations/type_flow/transformer/regress_47878.dart b/pkg/vm/testcases/transformations/type_flow/transformer/regress_47878.dart
new file mode 100644
index 0000000..866f945
--- /dev/null
+++ b/pkg/vm/testcases/transformations/type_flow/transformer/regress_47878.dart
@@ -0,0 +1,27 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// Regression test for https://github.com/dart-lang/sdk/issues/47878
+
+abstract class Disposable {}
+
+class A {}
+
+class Data<T> {
+  T? value;
+}
+
+class DataStream<T> {
+  DataStream({newValue, Data<T>? stream}) {
+    var lastValue = stream!.value;
+
+    if (lastValue != null &&
+        lastValue is Disposable &&
+        lastValue != newValue) {}
+  }
+}
+
+void main() {
+  DataStream<A>();
+}
diff --git a/pkg/vm/testcases/transformations/type_flow/transformer/regress_47878.dart.expect b/pkg/vm/testcases/transformations/type_flow/transformer/regress_47878.dart.expect
new file mode 100644
index 0000000..d52c496
--- /dev/null
+++ b/pkg/vm/testcases/transformations/type_flow/transformer/regress_47878.dart.expect
@@ -0,0 +1,26 @@
+library #lib /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+abstract class Disposable extends core::Object {
+}
+abstract class A extends core::Object {
+}
+abstract class Data<T extends core::Object? = dynamic> extends core::Object {
+}
+class DataStream<T extends core::Object? = dynamic> extends core::Object {
+  constructor •() → self::DataStream<self::DataStream::T%>
+    : super core::Object::•() {
+    self::DataStream::T? lastValue = block {
+      #C1!;
+    } =>throw "Attempt to execute code removed by Dart AOT compiler (TFA)";
+    if(!(throw "Attempt to execute code removed by Dart AOT compiler (TFA)") && false && !([@vm.inferred-type.metadata=dart.core::bool (skip check) (receiver not int)] lastValue{self::DataStream::T & self::Disposable /* '!' & '!' = '!' */} =={core::Object::==}{(core::Object) → core::bool} #C1)) {
+    }
+  }
+}
+static method main() → void {
+  new self::DataStream::•<self::A>();
+}
+constants  {
+  #C1 = null
+}
diff --git a/pkg/vm/testcases/transformations/type_flow/transformer/tear_off_super_method.dart.expect b/pkg/vm/testcases/transformations/type_flow/transformer/tear_off_super_method.dart.expect
index 0e44dd5..86ad485 100644
--- a/pkg/vm/testcases/transformations/type_flow/transformer/tear_off_super_method.dart.expect
+++ b/pkg/vm/testcases/transformations/type_flow/transformer/tear_off_super_method.dart.expect
@@ -16,6 +16,8 @@
 [@vm.procedure-attributes.metadata=getterCalledDynamically:false,hasThisUses:false,hasTearOffUses:false,methodOrSetterSelectorId:1,getterSelectorId:2] [@vm.unboxing-info.metadata=()->i]  method foo() → core::int
     return _in::unsafeCast<core::int>([@vm.direct-call.metadata=dart.core::_IntegerImplementation.+] [@vm.inferred-type.metadata=int (skip check)] 1.{core::num::+}(_in::unsafeCast<core::num>([@vm.direct-call.metadata=#lib::B.foo] [@vm.inferred-type.metadata=int? (receiver not int)] [@vm.inferred-type.metadata=#lib::B] self::knownResult(){dynamic}.foo())){(core::num) → core::num});
 }
+class C extends core::Object implements self::A {
+}
 abstract class Base extends core::Object {
   synthetic constructor •() → self::Base
     : super core::Object::•()
diff --git a/pkg/vm/testcases/transformations/type_flow/transformer/tree_shake_enum_from_lib.dart.expect b/pkg/vm/testcases/transformations/type_flow/transformer/tree_shake_enum_from_lib.dart.expect
index 3aa20dc..446a1e7 100644
--- a/pkg/vm/testcases/transformations/type_flow/transformer/tree_shake_enum_from_lib.dart.expect
+++ b/pkg/vm/testcases/transformations/type_flow/transformer/tree_shake_enum_from_lib.dart.expect
@@ -51,6 +51,6 @@
   synthetic constructor •() → self::ConstClass
     : super core::Object::•()
     ;
-[@vm.procedure-attributes.metadata=methodOrSetterCalledDynamically:false,getterCalledDynamically:false,hasThisUses:false,hasTearOffUses:false,methodOrSetterSelectorId:3258,getterSelectorId:3259]  method method([@vm.inferred-type.metadata=dart.core::Null? (value: null)] self::ConstEnum e) → core::int
+[@vm.procedure-attributes.metadata=methodOrSetterCalledDynamically:false,getterCalledDynamically:false,hasThisUses:false,hasTearOffUses:false,methodOrSetterSelectorId:3384,getterSelectorId:3385]  method method([@vm.inferred-type.metadata=dart.core::Null? (value: null)] self::ConstEnum e) → core::int
     return [@vm.inferred-type.metadata=!] e.{core::_Enum::index}{core::int};
 }
diff --git a/pkg/vm/testcases/transformations/type_flow/transformer/write_only_field.dart.expect b/pkg/vm/testcases/transformations/type_flow/transformer/write_only_field.dart.expect
index e544ddf..1d30a71 100644
--- a/pkg/vm/testcases/transformations/type_flow/transformer/write_only_field.dart.expect
+++ b/pkg/vm/testcases/transformations/type_flow/transformer/write_only_field.dart.expect
@@ -2,6 +2,8 @@
 import self as self;
 import "dart:core" as core;
 
+class A extends core::Object {
+}
 class B extends core::Object {
   constructor •() → self::B
     : super core::Object::•() {
diff --git a/pkg/vm_service/CHANGELOG.md b/pkg/vm_service/CHANGELOG.md
index 16605c0..e096691 100644
--- a/pkg/vm_service/CHANGELOG.md
+++ b/pkg/vm_service/CHANGELOG.md
@@ -1,6 +1,11 @@
 # Changelog
 
+## 8.1.0
+- Update to version `3.55` of the spec.
+- Added `streamCpuSamplesWithUserTag` RPC.
+
 ## 8.0.0
+- Update to version `3.54` of the spec.
 - *breaking* Updated type of `Event.cpuSamples` from `CpuSamples` to
   `CpuSamplesEvent`, which is less expensive to generate and serialize.
 - Added `CpuSamplesEvent` object.
diff --git a/pkg/vm_service/java/version.properties b/pkg/vm_service/java/version.properties
index 84daa3b..e465dc5 100644
--- a/pkg/vm_service/java/version.properties
+++ b/pkg/vm_service/java/version.properties
@@ -1 +1 @@
-version=3.54
+version=3.55
diff --git a/pkg/vm_service/lib/src/vm_service.dart b/pkg/vm_service/lib/src/vm_service.dart
index fcdfe9b..968a41f 100644
--- a/pkg/vm_service/lib/src/vm_service.dart
+++ b/pkg/vm_service/lib/src/vm_service.dart
@@ -26,7 +26,7 @@
         HeapSnapshotObjectNoData,
         HeapSnapshotObjectNullData;
 
-const String vmServiceVersion = '3.54.0';
+const String vmServiceVersion = '3.55.0';
 
 /// @optional
 const String optional = 'optional';
@@ -245,6 +245,7 @@
   'setVMName': const ['Success'],
   'setVMTimelineFlags': const ['Success'],
   'streamCancel': const ['Success'],
+  'streamCpuSamplesWithUserTag': const ['Success'],
   'streamListen': const ['Success'],
 };
 
@@ -1205,6 +1206,15 @@
   /// See [Success].
   Future<Success> streamCancel(String streamId);
 
+  /// The `streamCpuSamplesWithUserTag` RPC allows for clients to specify which
+  /// CPU samples collected by the profiler should be sent over the `Profiler`
+  /// stream. When called, the VM will stream `CpuSamples` events containing
+  /// `CpuSample`'s collected while a user tag contained in `userTags` was
+  /// active.
+  ///
+  /// See [Success].
+  Future<Success> streamCpuSamplesWithUserTag(List<String> userTags);
+
   /// The `streamListen` RPC subscribes to a stream in the VM. Once subscribed,
   /// the client will begin receiving events from the stream.
   ///
@@ -1640,6 +1650,11 @@
           await existing.cancel();
           response = Success();
           break;
+        case 'streamCpuSamplesWithUserTag':
+          response = await _serviceImplementation.streamCpuSamplesWithUserTag(
+            List<String>.from(params!['userTags'] ?? []),
+          );
+          break;
         case 'streamListen':
           var id = params!['streamId'];
           if (_streamSubscriptions.containsKey(id)) {
@@ -2169,6 +2184,10 @@
       _call('streamCancel', {'streamId': streamId});
 
   @override
+  Future<Success> streamCpuSamplesWithUserTag(List<String> userTags) =>
+      _call('streamCpuSamplesWithUserTag', {'userTags': userTags});
+
+  @override
   Future<Success> streamListen(String streamId) =>
       _call('streamListen', {'streamId': streamId});
 
diff --git a/pkg/vm_service/pubspec.yaml b/pkg/vm_service/pubspec.yaml
index d613713..a01b273 100644
--- a/pkg/vm_service/pubspec.yaml
+++ b/pkg/vm_service/pubspec.yaml
@@ -3,7 +3,7 @@
   A library to communicate with a service implementing the Dart VM
   service protocol.
 
-version: 8.0.0
+version: 8.1.0
 
 homepage: https://github.com/dart-lang/sdk/tree/master/pkg/vm_service
 
diff --git a/runtime/BUILD.gn b/runtime/BUILD.gn
index dd25e81..8b3999a 100644
--- a/runtime/BUILD.gn
+++ b/runtime/BUILD.gn
@@ -132,6 +132,9 @@
     defines += [ "DART_USE_TCMALLOC" ]
     include_dirs += [ "../third_party/tcmalloc/gperftools/src" ]
   }
+  if (dart_use_mallinfo2) {
+    defines += [ "DART_USE_MALLINFO2" ]
+  }
 
   if (dart_use_compressed_pointers) {
     defines += [ "DART_COMPRESSED_POINTERS" ]
diff --git a/runtime/bin/dart_embedder_api_impl.cc b/runtime/bin/dart_embedder_api_impl.cc
index 88c641f..9ba84e9 100644
--- a/runtime/bin/dart_embedder_api_impl.cc
+++ b/runtime/bin/dart_embedder_api_impl.cc
@@ -17,17 +17,17 @@
 namespace embedder {
 
 static char* MallocFormatedString(const char* format, ...) {
-  va_list args;
-  va_start(args, format);
-  intptr_t len = vsnprintf(NULL, 0, format, args);
-  va_end(args);
+  va_list measure_args;
+  va_start(measure_args, format);
+  intptr_t len = vsnprintf(NULL, 0, format, measure_args);
+  va_end(measure_args);
 
   char* buffer = reinterpret_cast<char*>(malloc(len + 1));
   MSAN_UNPOISON(buffer, (len + 1));
-  va_list args2;
-  va_start(args2, format);
-  vsnprintf(buffer, (len + 1), format, args2);
-  va_end(args2);
+  va_list print_args;
+  va_start(print_args, format);
+  vsnprintf(buffer, (len + 1), format, print_args);
+  va_end(print_args);
   return buffer;
 }
 
diff --git a/runtime/bin/dartdev_isolate.cc b/runtime/bin/dartdev_isolate.cc
index 0f75c8e..4b9fe69 100644
--- a/runtime/bin/dartdev_isolate.cc
+++ b/runtime/bin/dartdev_isolate.cc
@@ -210,6 +210,7 @@
   flags.use_field_guards = true;
   flags.use_osr = true;
   flags.is_system_isolate = true;
+  flags.branch_coverage = false;
 
   char* error;
   Dart_Isolate dartdev_isolate = runner->create_isolate_(
diff --git a/runtime/bin/dartutils.cc b/runtime/bin/dartutils.cc
index 565753d..05a500e 100644
--- a/runtime/bin/dartutils.cc
+++ b/runtime/bin/dartutils.cc
@@ -729,17 +729,17 @@
 }
 
 Dart_Handle DartUtils::NewError(const char* format, ...) {
-  va_list args;
-  va_start(args, format);
-  intptr_t len = vsnprintf(NULL, 0, format, args);
-  va_end(args);
+  va_list measure_args;
+  va_start(measure_args, format);
+  intptr_t len = vsnprintf(NULL, 0, format, measure_args);
+  va_end(measure_args);
 
   char* buffer = reinterpret_cast<char*>(Dart_ScopeAllocate(len + 1));
   MSAN_UNPOISON(buffer, (len + 1));
-  va_list args2;
-  va_start(args2, format);
-  vsnprintf(buffer, (len + 1), format, args2);
-  va_end(args2);
+  va_list print_args;
+  va_start(print_args, format);
+  vsnprintf(buffer, (len + 1), format, print_args);
+  va_end(print_args);
 
   return Dart_NewApiError(buffer);
 }
@@ -749,17 +749,17 @@
 }
 
 Dart_Handle DartUtils::NewStringFormatted(const char* format, ...) {
-  va_list args;
-  va_start(args, format);
-  intptr_t len = vsnprintf(NULL, 0, format, args);
-  va_end(args);
+  va_list measure_args;
+  va_start(measure_args, format);
+  intptr_t len = vsnprintf(NULL, 0, format, measure_args);
+  va_end(measure_args);
 
   char* buffer = reinterpret_cast<char*>(Dart_ScopeAllocate(len + 1));
   MSAN_UNPOISON(buffer, (len + 1));
-  va_list args2;
-  va_start(args2, format);
-  vsnprintf(buffer, (len + 1), format, args2);
-  va_end(args2);
+  va_list print_args;
+  va_start(print_args, format);
+  vsnprintf(buffer, (len + 1), format, print_args);
+  va_end(print_args);
 
   return NewString(buffer);
 }
diff --git a/runtime/bin/ffi_test/ffi_test_functions.cc b/runtime/bin/ffi_test/ffi_test_functions.cc
index 1784af3..dd5e41f 100644
--- a/runtime/bin/ffi_test/ffi_test_functions.cc
+++ b/runtime/bin/ffi_test/ffi_test_functions.cc
@@ -1133,4 +1133,38 @@
   return sizeof(Struct3BytesPackedIntCopy);
 }
 
+// Define ssize_t for Windows as intptr_t.
+#if defined(_WIN32)
+typedef intptr_t ssize_t;
+#endif
+
+#define DEFINE_SIZE_OF(type_modifier, type)                                    \
+  DART_EXPORT uint64_t FfiSizeOf_##type_modifier##_##type() {                  \
+    return sizeof(type_modifier type);                                         \
+  }
+
+#define SIZES(F)                                                               \
+  F(, intptr_t)                                                                \
+  F(, uintptr_t)                                                               \
+  F(, int)                                                                     \
+  F(unsigned, int)                                                             \
+  F(, long)         /* NOLINT */                                               \
+  F(unsigned, long) /* NOLINT */                                               \
+  F(, wchar_t)                                                                 \
+  F(, size_t)                                                                  \
+  F(, ssize_t)                                                                 \
+  F(, off_t)
+
+SIZES(DEFINE_SIZE_OF)
+
+#undef DEFINE_SIZE_OF
+#undef SIZES
+
+DART_EXPORT int64_t WCharMinValue() {
+  return WCHAR_MIN;
+}
+DART_EXPORT int64_t WCharMaxValue() {
+  return WCHAR_MAX;
+}
+
 }  // namespace dart
diff --git a/runtime/bin/ffi_test/ffi_test_functions_generated.cc b/runtime/bin/ffi_test/ffi_test_functions_generated.cc
index dc17bb0..724fe55 100644
--- a/runtime/bin/ffi_test/ffi_test_functions_generated.cc
+++ b/runtime/bin/ffi_test/ffi_test_functions_generated.cc
@@ -566,6 +566,10 @@
   Struct16BytesHomogeneousFloat a2;
 };
 
+struct StructInlineArrayInt {
+  wchar_t a0[10];
+};
+
 // Used for testing structs and unions by value.
 // Smallest struct with data.
 // 10 struct arguments will exhaust available registers.
@@ -4895,6 +4899,46 @@
 }
 
 // Used for testing structs and unions by value.
+// Returning a wchar.
+DART_EXPORT wchar_t PassWCharStructInlineArrayIntUintPtrx2LongUnsigned(
+    wchar_t a0,
+    StructInlineArrayInt a1,
+    uintptr_t a2,
+    uintptr_t a3,
+    /* NOLINT(runtime/int) */ long a4,
+    /* NOLINT(runtime/int) */ unsigned long a5) {
+  std::cout << "PassWCharStructInlineArrayIntUintPtrx2LongUnsigned"
+            << "(" << a0 << ", ([" << a1.a0[0] << ", " << a1.a0[1] << ", "
+            << a1.a0[2] << ", " << a1.a0[3] << ", " << a1.a0[4] << ", "
+            << a1.a0[5] << ", " << a1.a0[6] << ", " << a1.a0[7] << ", "
+            << a1.a0[8] << ", " << a1.a0[9] << "]), " << a2 << ", " << a3
+            << ", " << a4 << ", " << a5 << ")"
+            << "\n";
+
+  wchar_t result = 0;
+
+  result += a0;
+  result += a1.a0[0];
+  result += a1.a0[1];
+  result += a1.a0[2];
+  result += a1.a0[3];
+  result += a1.a0[4];
+  result += a1.a0[5];
+  result += a1.a0[6];
+  result += a1.a0[7];
+  result += a1.a0[8];
+  result += a1.a0[9];
+  result += a2;
+  result += a3;
+  result += a4;
+  result += a5;
+
+  std::cout << "result = " << result << "\n";
+
+  return result;
+}
+
+// Used for testing structs and unions by value.
 // Smallest struct with data.
 DART_EXPORT Struct1ByteInt ReturnStruct1ByteInt(int8_t a0) {
   std::cout << "ReturnStruct1ByteInt"
@@ -12599,21 +12643,85 @@
 
   std::cout << "result = " << result << "\n";
 
-  CHECK_APPROX(1, result);
+  CHECK_EQ(1, result);
 
   // Pass argument that will make the Dart callback throw.
   a0 = 42;
 
   result = f(a0, a1);
 
-  CHECK_APPROX(0.0, result);
+  CHECK_EQ(0, result);
 
   // Pass argument that will make the Dart callback return null.
   a0 = 84;
 
   result = f(a0, a1);
 
-  CHECK_APPROX(0.0, result);
+  CHECK_EQ(0, result);
+
+  return 0;
+}
+
+// Used for testing structs and unions by value.
+// Returning a wchar.
+DART_EXPORT intptr_t TestPassWCharStructInlineArrayIntUintPtrx2LongUnsigned(
+    // NOLINTNEXTLINE(whitespace/parens)
+    wchar_t (*f)(wchar_t a0,
+                 StructInlineArrayInt a1,
+                 uintptr_t a2,
+                 uintptr_t a3,
+                 /* NOLINT(runtime/int) */ long a4,
+                 /* NOLINT(runtime/int) */ unsigned long a5)) {
+  wchar_t a0;
+  StructInlineArrayInt a1 = {};
+  uintptr_t a2;
+  uintptr_t a3;
+  /* NOLINT(runtime/int) */ long a4;
+  /* NOLINT(runtime/int) */ unsigned long a5;
+
+  a0 = 1;
+  a1.a0[0] = 2;
+  a1.a0[1] = 3;
+  a1.a0[2] = 4;
+  a1.a0[3] = 5;
+  a1.a0[4] = 6;
+  a1.a0[5] = 7;
+  a1.a0[6] = 8;
+  a1.a0[7] = 9;
+  a1.a0[8] = 10;
+  a1.a0[9] = 11;
+  a2 = 12;
+  a3 = 13;
+  a4 = 14;
+  a5 = 15;
+
+  std::cout << "Calling TestPassWCharStructInlineArrayIntUintPtrx2LongUnsigned("
+            << "(" << a0 << ", ([" << a1.a0[0] << ", " << a1.a0[1] << ", "
+            << a1.a0[2] << ", " << a1.a0[3] << ", " << a1.a0[4] << ", "
+            << a1.a0[5] << ", " << a1.a0[6] << ", " << a1.a0[7] << ", "
+            << a1.a0[8] << ", " << a1.a0[9] << "]), " << a2 << ", " << a3
+            << ", " << a4 << ", " << a5 << ")"
+            << ")\n";
+
+  wchar_t result = f(a0, a1, a2, a3, a4, a5);
+
+  std::cout << "result = " << result << "\n";
+
+  CHECK_EQ(120, result);
+
+  // Pass argument that will make the Dart callback throw.
+  a0 = 42;
+
+  result = f(a0, a1, a2, a3, a4, a5);
+
+  CHECK_EQ(0, result);
+
+  // Pass argument that will make the Dart callback return null.
+  a0 = 84;
+
+  result = f(a0, a1, a2, a3, a4, a5);
+
+  CHECK_EQ(0, result);
 
   return 0;
 }
diff --git a/runtime/bin/gen_snapshot.cc b/runtime/bin/gen_snapshot.cc
index 00cf482..6a24139 100644
--- a/runtime/bin/gen_snapshot.cc
+++ b/runtime/bin/gen_snapshot.cc
@@ -879,6 +879,10 @@
   if (IsSnapshottingForPrecompilation()) {
     vm_options.AddArgument("--precompilation");
   } else if ((snapshot_kind == kCoreJIT) || (snapshot_kind == kAppJIT)) {
+    // Core-jit and app-jit snapshot can be deployed to another machine,
+    // so  generated code should not depend on the CPU features
+    // of the system where snapshot was generated.
+    vm_options.AddArgument("--target-unknown-cpu");
 #if !defined(TARGET_ARCH_IA32)
     vm_options.AddArgument("--link_natives_lazily");
 #endif
diff --git a/runtime/bin/io_natives.cc b/runtime/bin/io_natives.cc
index efa37c8..17b9404 100644
--- a/runtime/bin/io_natives.cc
+++ b/runtime/bin/io_natives.cc
@@ -144,7 +144,7 @@
   V(SocketBase_IsBindError, 2)                                                 \
   V(Socket_Available, 1)                                                       \
   V(Socket_AvailableDatagram, 1)                                               \
-  V(Socket_CreateBindConnect, 5)                                               \
+  V(Socket_CreateBindConnect, 6)                                               \
   V(Socket_CreateUnixDomainBindConnect, 4)                                     \
   V(Socket_CreateBindDatagram, 6)                                              \
   V(Socket_CreateConnect, 4)                                                   \
diff --git a/runtime/bin/main.cc b/runtime/bin/main.cc
index 88e7c9e9..d03555a 100644
--- a/runtime/bin/main.cc
+++ b/runtime/bin/main.cc
@@ -1242,6 +1242,12 @@
 #if defined(DART_PRECOMPILED_RUNTIME)
   vm_options.AddArgument("--precompilation");
 #endif
+  if (Options::gen_snapshot_kind() == kAppJIT) {
+    // App-jit snapshot can be deployed to another machine,
+    // so generated code should not depend on the CPU features
+    // of the system where snapshot was generated.
+    vm_options.AddArgument("--target-unknown-cpu");
+  }
   // If we need to write an app-jit snapshot or a depfile, then add an exit
   // hook that writes the snapshot and/or depfile as appropriate.
   if ((Options::gen_snapshot_kind() == kAppJIT) ||
diff --git a/runtime/bin/socket.cc b/runtime/bin/socket.cc
index 62cc613..21bfadf 100644
--- a/runtime/bin/socket.cc
+++ b/runtime/bin/socket.cc
@@ -396,8 +396,13 @@
   SocketAddress::SetAddrPort(&addr, static_cast<intptr_t>(port));
   RawAddr sourceAddr;
   SocketAddress::GetSockAddr(Dart_GetNativeArgument(args, 3), &sourceAddr);
+  Dart_Handle source_port_arg = Dart_GetNativeArgument(args, 4);
+  int64_t source_port =
+      DartUtils::GetInt64ValueCheckRange(source_port_arg, 0, 65535);
+  SocketAddress::SetAddrPort(&sourceAddr, static_cast<intptr_t>(source_port));
+
   if (addr.addr.sa_family == AF_INET6) {
-    Dart_Handle scope_id_arg = Dart_GetNativeArgument(args, 4);
+    Dart_Handle scope_id_arg = Dart_GetNativeArgument(args, 5);
     int64_t scope_id =
         DartUtils::GetInt64ValueCheckRange(scope_id_arg, 0, 65535);
     SocketAddress::SetAddrScope(&addr, scope_id);
diff --git a/runtime/include/dart_api.h b/runtime/include/dart_api.h
index e79e6c4..f37de2b 100644
--- a/runtime/include/dart_api.h
+++ b/runtime/include/dart_api.h
@@ -606,6 +606,7 @@
   bool null_safety;
   bool is_system_isolate;
   bool snapshot_is_dontneed_safe;
+  bool branch_coverage;
 } Dart_IsolateFlags;
 
 /**
diff --git a/runtime/lib/ffi.cc b/runtime/lib/ffi.cc
index 9f0bf75..2c54160 100644
--- a/runtime/lib/ffi.cc
+++ b/runtime/lib/ffi.cc
@@ -26,6 +26,7 @@
 #include "vm/compiler/assembler/assembler.h"
 #include "vm/compiler/ffi/call.h"
 #include "vm/compiler/ffi/callback.h"
+#include "vm/compiler/ffi/marshaller.h"
 #include "vm/compiler/jit/compiler.h"
 #endif  // !defined(DART_PRECOMPILED_RUNTIME)
 
@@ -98,6 +99,15 @@
   func = func.parent_function();
   ASSERT(func.is_static());
 
+  // AbiSpecificTypes can have an incomplete mapping.
+  const char* error = nullptr;
+  compiler::ffi::NativeFunctionTypeFromFunctionType(zone, native_signature,
+                                                    &error);
+  if (error != nullptr) {
+    Exceptions::ThrowCompileTimeError(LanguageError::Handle(
+        zone, LanguageError::New(String::Handle(zone, String::New(error)))));
+  }
+
   // We are returning an object which is not an Instance here. This is only OK
   // because we know that the result will be passed directly to
   // _pointerFromFunction and will not leak out into user code.
diff --git a/runtime/lib/object.cc b/runtime/lib/object.cc
index f8e903e..2b7a470 100644
--- a/runtime/lib/object.cc
+++ b/runtime/lib/object.cc
@@ -48,20 +48,14 @@
   // Please note that no handle is created for the argument.
   // This is safe since the argument is only used in a tail call.
   // The performance benefit is more than 5% when using hashCode.
-  return Smi::New(GetHash(isolate, arguments->NativeArgAt(0)));
-}
+  intptr_t hash = GetHash(isolate, arguments->NativeArgAt(0));
+  if (LIKELY(hash != 0)) {
+    return Smi::New(hash);
+  }
 
-DEFINE_NATIVE_ENTRY(Object_setHashIfNotSetYet, 0, 2) {
-  GET_NON_NULL_NATIVE_ARGUMENT(Smi, hash, arguments->NativeArgAt(1));
-#if defined(HASH_IN_OBJECT_HEADER)
-  return Smi::New(
-      Object::SetCachedHashIfNotSet(arguments->NativeArgAt(0), hash.Value()));
-#else
   const Instance& instance =
       Instance::CheckedHandle(zone, arguments->NativeArgAt(0));
-  Heap* heap = thread->heap();
-  return Smi::New(heap->SetHashIfNotSet(instance.ptr(), hash.Value()));
-#endif
+  return instance.IdentityHashCode(arguments->thread());
 }
 
 DEFINE_NATIVE_ENTRY(Object_toString, 0, 1) {
diff --git a/runtime/lib/vmservice.cc b/runtime/lib/vmservice.cc
index f3dba9a..1f0744a 100644
--- a/runtime/lib/vmservice.cc
+++ b/runtime/lib/vmservice.cc
@@ -384,4 +384,72 @@
 #endif
 }
 
+#ifndef PRODUCT
+class UserTagIsolatesVisitor : public IsolateVisitor {
+ public:
+  UserTagIsolatesVisitor(Thread* thread,
+                         const GrowableObjectArray* user_tags,
+                         bool set_streamable)
+      : IsolateVisitor(),
+        thread_(thread),
+        user_tags_(user_tags),
+        set_streamable_(set_streamable) {}
+
+  virtual void VisitIsolate(Isolate* isolate) {
+    if (Isolate::IsVMInternalIsolate(isolate)) {
+      return;
+    }
+    Zone* zone = thread_->zone();
+    UserTag& tag = UserTag::Handle(zone);
+    String& label = String::Handle(zone);
+    for (intptr_t i = 0; i < user_tags_->Length(); ++i) {
+      label ^= user_tags_->At(i);
+      tag ^= UserTag::FindTagInIsolate(isolate, thread_, label);
+      if (!tag.IsNull()) {
+        tag.set_streamable(set_streamable_);
+      }
+    }
+  }
+
+ private:
+  Thread* thread_;
+  const GrowableObjectArray* user_tags_;
+  bool set_streamable_;
+
+  DISALLOW_COPY_AND_ASSIGN(UserTagIsolatesVisitor);
+};
+#endif  // !PRODUCT
+
+DEFINE_NATIVE_ENTRY(VMService_AddUserTagsToStreamableSampleList, 0, 1) {
+#ifndef PRODUCT
+  GET_NON_NULL_NATIVE_ARGUMENT(GrowableObjectArray, user_tags,
+                               arguments->NativeArgAt(0));
+
+  Object& obj = Object::Handle();
+  for (intptr_t i = 0; i < user_tags.Length(); ++i) {
+    obj = user_tags.At(i);
+    UserTags::AddStreamableTagName(obj.ToCString());
+  }
+  UserTagIsolatesVisitor visitor(thread, &user_tags, true);
+  Isolate::VisitIsolates(&visitor);
+#endif
+  return Object::null();
+}
+
+DEFINE_NATIVE_ENTRY(VMService_RemoveUserTagsFromStreamableSampleList, 0, 1) {
+#ifndef PRODUCT
+  GET_NON_NULL_NATIVE_ARGUMENT(GrowableObjectArray, user_tags,
+                               arguments->NativeArgAt(0));
+
+  Object& obj = Object::Handle();
+  for (intptr_t i = 0; i < user_tags.Length(); ++i) {
+    obj = user_tags.At(i);
+    UserTags::RemoveStreamableTagName(obj.ToCString());
+  }
+  UserTagIsolatesVisitor visitor(thread, &user_tags, false);
+  Isolate::VisitIsolates(&visitor);
+#endif
+  return Object::null();
+}
+
 }  // namespace dart
diff --git a/runtime/observatory/tests/service/get_version_rpc_test.dart b/runtime/observatory/tests/service/get_version_rpc_test.dart
index 59afe6d..048b1e4 100644
--- a/runtime/observatory/tests/service/get_version_rpc_test.dart
+++ b/runtime/observatory/tests/service/get_version_rpc_test.dart
@@ -12,7 +12,7 @@
     final result = await vm.invokeRpcNoUpgrade('getVersion', {});
     expect(result['type'], 'Version');
     expect(result['major'], 3);
-    expect(result['minor'], 54);
+    expect(result['minor'], 55);
     expect(result['_privateMajor'], 0);
     expect(result['_privateMinor'], 0);
   },
diff --git a/runtime/observatory/tests/service/service_kernel.status b/runtime/observatory/tests/service/service_kernel.status
index 412cfbc..ee4f627 100644
--- a/runtime/observatory/tests/service/service_kernel.status
+++ b/runtime/observatory/tests/service/service_kernel.status
@@ -212,6 +212,7 @@
 rewind_optimized_out_test: SkipSlow # Timeout
 
 [ $arch == ia32 && $compiler == dartk ]
+*: Slow # Issue 47920, service tests are slow on IA32
 valid_source_locations_test: Skip # Issue 34736, too slow.
 
 [ $compiler == app_jitk && $system == linux ]
diff --git a/runtime/observatory_2/tests/service_2/get_version_rpc_test.dart b/runtime/observatory_2/tests/service_2/get_version_rpc_test.dart
index 4daa57a..a3c7061 100644
--- a/runtime/observatory_2/tests/service_2/get_version_rpc_test.dart
+++ b/runtime/observatory_2/tests/service_2/get_version_rpc_test.dart
@@ -12,7 +12,7 @@
     final result = await vm.invokeRpcNoUpgrade('getVersion', {});
     expect(result['type'], equals('Version'));
     expect(result['major'], equals(3));
-    expect(result['minor'], equals(54));
+    expect(result['minor'], equals(55));
     expect(result['_privateMajor'], equals(0));
     expect(result['_privateMinor'], equals(0));
   },
diff --git a/runtime/observatory_2/tests/service_2/service_2_kernel.status b/runtime/observatory_2/tests/service_2/service_2_kernel.status
index ac51da2..914b102 100644
--- a/runtime/observatory_2/tests/service_2/service_2_kernel.status
+++ b/runtime/observatory_2/tests/service_2/service_2_kernel.status
@@ -212,6 +212,7 @@
 rewind_optimized_out_test: SkipSlow # Timeout
 
 [ $arch == ia32 && $compiler == dartk ]
+*: Slow # Issue 47920, service tests are slow on IA32
 valid_source_locations_test: Skip # Issue 34736, too slow.
 
 [ $compiler == app_jitk && $system == linux ]
diff --git a/runtime/platform/assert.h b/runtime/platform/assert.h
index ce4d0cc..53079e3 100644
--- a/runtime/platform/assert.h
+++ b/runtime/platform/assert.h
@@ -140,13 +140,33 @@
        tols.c_str());
 }
 
+static void Escape(std::string& dst, const char* src) {
+  char c;
+  while ((c = *src++) != '\0') {
+    if (c == '\n') {
+      dst += "\\n\"\n\"";
+    } else if (c == '\'') {
+      dst += "\\\'";
+    } else if (c == '\"') {
+      dst += "\\\"";
+    } else if (c == '\\') {
+      dst += "\\\\";
+    } else {
+      dst += c;
+    }
+  }
+}
+
 inline void Expect::StringEquals(const char* expected, const char* actual) {
   if (strcmp(expected, actual) == 0) return;
   if (actual == nullptr) {
     Fail("expected:\n<\"%s\">\nbut was nullptr", expected);
   } else {
     if (strcmp(expected, actual) == 0) return;
-    Fail("expected:\n<\"%s\">\nbut was:\n<\"%s\">", expected, actual);
+    std::string es, as;
+    Escape(es, expected);
+    Escape(as, actual);
+    Fail("expected:\n<\"%s\">\nbut was:\n<\"%s\">", es.c_str(), as.c_str());
   }
 }
 
diff --git a/runtime/platform/syslog_android.cc b/runtime/platform/syslog_android.cc
index 46930e9..e3d4599 100644
--- a/runtime/platform/syslog_android.cc
+++ b/runtime/platform/syslog_android.cc
@@ -19,18 +19,32 @@
   // If we launch the DartVM inside "adb shell" we will only get messages
   // (critical ones or not) if we print them to stdout/stderr.
   // We also log using android's logging system.
-  vprintf(format, args);
+  va_list stdio_args;
+  va_copy(stdio_args, args);
+  vprintf(format, stdio_args);
   fflush(stdout);
-  __android_log_vprint(ANDROID_LOG_INFO, "Dart", format, args);
+  va_end(stdio_args);
+
+  va_list log_args;
+  va_copy(log_args, args);
+  __android_log_vprint(ANDROID_LOG_INFO, "Dart", format, log_args);
+  va_end(log_args);
 }
 
 void Syslog::VPrintErr(const char* format, va_list args) {
   // If we launch the DartVM inside "adb shell" we will only get messages
   // (critical ones or not) if we print them to stdout/stderr.
   // We also log using android's logging system.
-  vfprintf(stderr, format, args);
+  va_list stdio_args;
+  va_copy(stdio_args, args);
+  vfprintf(stderr, format, stdio_args);
   fflush(stderr);
-  __android_log_vprint(ANDROID_LOG_ERROR, "Dart", format, args);
+  va_end(stdio_args);
+
+  va_list log_args;
+  va_copy(log_args, args);
+  __android_log_vprint(ANDROID_LOG_ERROR, "Dart", format, log_args);
+  va_end(log_args);
 }
 
 }  // namespace dart
diff --git a/runtime/platform/thread_sanitizer.h b/runtime/platform/thread_sanitizer.h
index baff130..b82fde9 100644
--- a/runtime/platform/thread_sanitizer.h
+++ b/runtime/platform/thread_sanitizer.h
@@ -21,4 +21,16 @@
 #define NO_SANITIZE_THREAD
 #endif
 
+#if defined(USING_THREAD_SANITIZER)
+#define DO_IF_TSAN(CODE) CODE
+#else
+#define DO_IF_TSAN(CODE)
+#endif
+
+#if defined(USING_THREAD_SANITIZER)
+#define DO_IF_NOT_TSAN(CODE)
+#else
+#define DO_IF_NOT_TSAN(CODE) CODE
+#endif
+
 #endif  // RUNTIME_PLATFORM_THREAD_SANITIZER_H_
diff --git a/runtime/platform/utils.cc b/runtime/platform/utils.cc
index c93c84b..eb833e7 100644
--- a/runtime/platform/utils.cc
+++ b/runtime/platform/utils.cc
@@ -361,7 +361,7 @@
   *error = status != nullptr ? strdup(status) : nullptr;
 #elif defined(DART_HOST_OS_WINDOWS)
   const int status = GetLastError();
-  *error = status != 0 ? Utils::SCreate("error code %i", error) : nullptr;
+  *error = status != 0 ? Utils::SCreate("error code %i", status) : nullptr;
 #else
   *error = Utils::StrDup("loading dynamic libraries is not supported");
 #endif
diff --git a/runtime/runtime_args.gni b/runtime/runtime_args.gni
index ae564be..8219c51 100644
--- a/runtime/runtime_args.gni
+++ b/runtime/runtime_args.gni
@@ -46,6 +46,10 @@
   # the VM enables this only for Linux builds.
   dart_use_tcmalloc = false
 
+  # Whether to use mallinfo2 instead of mallinfo which is deprecated starting
+  # with libc 2.33
+  dart_use_mallinfo2 = false
+
   # Whether to link Crashpad library for crash handling. Only supported on
   # Windows for now.
   dart_use_crashpad = false
diff --git a/runtime/tests/vm/dart/print_object_layout_script.dart b/runtime/tests/vm/dart/print_object_layout_script.dart
new file mode 100644
index 0000000..d063d6a
--- /dev/null
+++ b/runtime/tests/vm/dart/print_object_layout_script.dart
@@ -0,0 +1,25 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// Test script for print_object_layout_test.dart
+
+class ClassA {
+  String fieldA1 = 'a';
+  int fieldA2 = 1;
+}
+
+class ClassB extends ClassA {
+  String fieldB1 = 'b';
+  int fieldB2 = 2;
+  int unusedB3 = 3;
+  static int staticB4 = 4;
+}
+
+@pragma('vm:never-inline')
+useFields(ClassB obj) =>
+    "${obj.fieldA1}${obj.fieldA2}${obj.fieldB1}${obj.fieldB2}${ClassB.staticB4}";
+
+main() {
+  useFields(ClassB());
+}
diff --git a/runtime/tests/vm/dart/print_object_layout_test.dart b/runtime/tests/vm/dart/print_object_layout_test.dart
new file mode 100644
index 0000000..36620d6
--- /dev/null
+++ b/runtime/tests/vm/dart/print_object_layout_test.dart
@@ -0,0 +1,102 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// OtherResources=print_object_layout_script.dart
+
+// Test for --print-object-layout-to option of gen_snapshot.
+
+import 'dart:convert' show jsonDecode;
+import 'dart:math' show max;
+import 'dart:io' show File, Platform;
+
+import 'package:expect/expect.dart';
+import 'package:path/path.dart' as path;
+import 'use_flag_test_helper.dart';
+
+verifyObjectLayout(String path) {
+  final classes = jsonDecode(File(path).readAsStringSync());
+  var sizeA, fieldsA;
+  var sizeB, fieldsB;
+  for (var cls in classes) {
+    if (cls['class'] == 'ClassA') {
+      sizeA = cls['size'].toInt();
+      fieldsA = cls['fields'];
+      print(cls);
+    } else if (cls['class'] == 'ClassB') {
+      sizeB = cls['size'].toInt();
+      fieldsB = cls['fields'];
+      print(cls);
+    }
+  }
+  Expect.isNotNull(sizeA);
+  Expect.isTrue(sizeA > 0);
+  Expect.isTrue(fieldsA.length == 2);
+  int maxOffsetA = 0;
+  for (var field in fieldsA) {
+    String fieldName = field['field'];
+    Expect.isTrue(fieldName == 'fieldA1' || fieldName == 'fieldA2');
+    int offset = field['offset'].toInt();
+    Expect.isTrue((offset > 0) && (offset < sizeA));
+    maxOffsetA = max(offset, maxOffsetA);
+  }
+
+  Expect.isNotNull(sizeB);
+  Expect.isTrue(sizeB > 0);
+  Expect.isTrue(sizeA <= sizeB);
+  Expect.isTrue(fieldsB.length == 3);
+  for (var field in fieldsB) {
+    String fieldName = field['field'];
+    if (fieldName == 'staticB4') {
+      Expect.isTrue(field['static']);
+    } else {
+      Expect.isTrue(fieldName == 'fieldB1' || fieldName == 'fieldB2');
+      int offset = field['offset'].toInt();
+      Expect.isTrue((offset > 0) && (offset < sizeB));
+      Expect.isTrue(offset > maxOffsetA);
+    }
+  }
+}
+
+main() async {
+  if (!isAOTRuntime) {
+    return; // Running in JIT: AOT binaries not available.
+  }
+
+  if (Platform.isAndroid) {
+    return; // SDK tree not available on the test device.
+  }
+
+  // These are the tools we need to be available to run on a given platform:
+  if (!File(platformDill).existsSync()) {
+    throw "Cannot run test as $platformDill does not exist";
+  }
+  if (!await testExecutable(genSnapshot)) {
+    throw "Cannot run test as $genSnapshot not available";
+  }
+
+  final testScriptUri =
+      Platform.script.resolve('print_object_layout_script.dart');
+
+  await withTempDir('print-object-layout-test', (String temp) async {
+    final appDillPath = path.join(temp, 'app.dill');
+    final snapshotPath = path.join(temp, 'aot.snapshot');
+    final objectLayoutPath = path.join(temp, 'layout.json');
+
+    await run(genKernel, <String>[
+      '--aot',
+      '--platform=$platformDill',
+      '--output=$appDillPath',
+      testScriptUri.toFilePath(),
+    ]);
+
+    await run(genSnapshot, <String>[
+      '--snapshot-kind=app-aot-elf',
+      '--elf=$snapshotPath',
+      '--print-object-layout-to=$objectLayoutPath',
+      appDillPath,
+    ]);
+
+    verifyObjectLayout(objectLayoutPath);
+  });
+}
diff --git a/runtime/tests/vm/dart/regress47472_test.dart b/runtime/tests/vm/dart/regress47472_test.dart
new file mode 100644
index 0000000..a3f8f8b
--- /dev/null
+++ b/runtime/tests/vm/dart/regress47472_test.dart
@@ -0,0 +1,11 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+main() {
+  for (int i = 0; i < 1000000; ++i) {
+    try {
+      throw 'a';
+    } catch (e, s) {}
+  }
+}
diff --git a/runtime/tests/vm/dart/regress_36636_test.dart b/runtime/tests/vm/dart/regress_36636_test.dart
index 1daf616..2fee620 100644
--- a/runtime/tests/vm/dart/regress_36636_test.dart
+++ b/runtime/tests/vm/dart/regress_36636_test.dart
@@ -2,6 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// VMOptions=--intrinsify=false --no-use-vfp
+// VMOptions=--intrinsify=false
 
 main() {}
diff --git a/runtime/tests/vm/dart/regress_flutter66765_test.dart b/runtime/tests/vm/dart/regress_flutter66765_test.dart
new file mode 100644
index 0000000..c47c966
--- /dev/null
+++ b/runtime/tests/vm/dart/regress_flutter66765_test.dart
@@ -0,0 +1,36 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// Regression test for https://github.com/flutter/flutter/issues/66765
+// Verifies that AOT compiler doesn't crash on a particular flow graph.
+
+class TutorialBloc {
+  TutorialBloc();
+
+  Stream<TutorialStates> mapEventToState(TutorialEvents event) async* {
+    switch (event.action) {
+      default:
+        yield TutorialInitState();
+    }
+  }
+}
+
+enum TutorialAction { dummyData }
+
+class TutorialEvents {
+  final TutorialAction action;
+  const TutorialEvents(this.action);
+}
+
+abstract class TutorialStates {}
+
+class TutorialInitState extends TutorialStates {}
+
+List<dynamic> l = [TutorialBloc()];
+
+void main() async {
+  if (l.length > 1) {
+    l[0].mapEventToState(42);
+  }
+}
diff --git a/runtime/tests/vm/dart/slow_path_shared_stub_test.dart b/runtime/tests/vm/dart/slow_path_shared_stub_test.dart
index fb4c4d1..6aabfed 100644
--- a/runtime/tests/vm/dart/slow_path_shared_stub_test.dart
+++ b/runtime/tests/vm/dart/slow_path_shared_stub_test.dart
@@ -3,7 +3,6 @@
 // BSD-style license that can be found in the LICENSE file.
 
 // VMOptions=--optimization_counter_threshold=10 --no-background-compilation --shared-slow-path-triggers-gc
-// VMOptions=--optimization_counter_threshold=10 --no-background-compilation --shared-slow-path-triggers-gc --no-use-vfp
 
 // This tests the stackmaps and environments for safepoints corresponding to
 // slow-path code which uses shared runtime stubs.
diff --git a/runtime/tests/vm/dart/typed_data_vfp_regress_42745_test.dart b/runtime/tests/vm/dart/typed_data_vfp_regress_42745_test.dart
index 294f0ea..f61edad 100644
--- a/runtime/tests/vm/dart/typed_data_vfp_regress_42745_test.dart
+++ b/runtime/tests/vm/dart/typed_data_vfp_regress_42745_test.dart
@@ -1,7 +1,6 @@
 // Copyright (c) 2020, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
-// VMOptions=--no-use-vfp
 
 import 'dart:typed_data';
 
diff --git a/runtime/tests/vm/dart/write_barrier_load_late_field_test.dart b/runtime/tests/vm/dart/write_barrier_load_late_field_test.dart
new file mode 100644
index 0000000..548a2d4
--- /dev/null
+++ b/runtime/tests/vm/dart/write_barrier_load_late_field_test.dart
@@ -0,0 +1,34 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// This test attempts to verify that the slow path for late static and
+// instance field initialization appropriately restores the write barrier
+// invariant.
+
+import 'dart:_internal';
+
+class Box {
+  var field;
+}
+
+late var global = (() {
+  VMInternalsForTesting.collectAllGarbage();
+  return 10;
+})();
+
+@pragma('vm:never-inline')
+foo() {
+  final kTrue = int.parse('1') == 1;
+  final box = Box(); // Ensure this box is allocated new
+  if (kTrue) {
+    global; // Will not block write-barrier elimination (GC in here should restore invariants)
+    box.field = Box()..field = 42; // Runtime should've made `box` remembered.
+    VMInternalsForTesting.collectAllGarbage();
+  }
+  return box;
+}
+
+main() {
+  if (foo().field.field != 42) throw 'a';
+}
diff --git a/runtime/tests/vm/dart_2/causal_stacks/utils.dart b/runtime/tests/vm/dart_2/causal_stacks/utils.dart
index a17cade..0d1489c 100644
--- a/runtime/tests/vm/dart_2/causal_stacks/utils.dart
+++ b/runtime/tests/vm/dart_2/causal_stacks/utils.dart
@@ -131,7 +131,7 @@
 
 Future listenAsyncStarThrowAsync() async {
   // Listening to an async* doesn't create the usual await-for StreamIterator.
-  StreamSubscription ss = asyncStarThrowAsync().listen((Future f) {});
+  StreamSubscription ss = asyncStarThrowAsync().listen((Future f) => 42);
   await ss.asFuture();
 }
 
diff --git a/runtime/tests/vm/dart_2/print_object_layout_script.dart b/runtime/tests/vm/dart_2/print_object_layout_script.dart
new file mode 100644
index 0000000..397fd1c
--- /dev/null
+++ b/runtime/tests/vm/dart_2/print_object_layout_script.dart
@@ -0,0 +1,27 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// @dart = 2.9
+
+// Test script for print_object_layout_test.dart
+
+class ClassA {
+  String fieldA1 = 'a';
+  int fieldA2 = 1;
+}
+
+class ClassB extends ClassA {
+  String fieldB1 = 'b';
+  int fieldB2 = 2;
+  int unusedB3 = 3;
+  static int staticB4 = 4;
+}
+
+@pragma('vm:never-inline')
+useFields(ClassB obj) =>
+    "${obj.fieldA1}${obj.fieldA2}${obj.fieldB1}${obj.fieldB2}${ClassB.staticB4}";
+
+main() {
+  useFields(ClassB());
+}
diff --git a/runtime/tests/vm/dart_2/print_object_layout_test.dart b/runtime/tests/vm/dart_2/print_object_layout_test.dart
new file mode 100644
index 0000000..e082bea
--- /dev/null
+++ b/runtime/tests/vm/dart_2/print_object_layout_test.dart
@@ -0,0 +1,104 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// @dart = 2.9
+
+// OtherResources=print_object_layout_script.dart
+
+// Test for --print-object-layout-to option of gen_snapshot.
+
+import 'dart:convert' show jsonDecode;
+import 'dart:math' show max;
+import 'dart:io' show File, Platform;
+
+import 'package:expect/expect.dart';
+import 'package:path/path.dart' as path;
+import 'use_flag_test_helper.dart';
+
+verifyObjectLayout(String path) {
+  final classes = jsonDecode(File(path).readAsStringSync());
+  var sizeA, fieldsA;
+  var sizeB, fieldsB;
+  for (var cls in classes) {
+    if (cls['class'] == 'ClassA') {
+      sizeA = cls['size'].toInt();
+      fieldsA = cls['fields'];
+      print(cls);
+    } else if (cls['class'] == 'ClassB') {
+      sizeB = cls['size'].toInt();
+      fieldsB = cls['fields'];
+      print(cls);
+    }
+  }
+  Expect.isNotNull(sizeA);
+  Expect.isTrue(sizeA > 0);
+  Expect.isTrue(fieldsA.length == 2);
+  int maxOffsetA = 0;
+  for (var field in fieldsA) {
+    String fieldName = field['field'];
+    Expect.isTrue(fieldName == 'fieldA1' || fieldName == 'fieldA2');
+    int offset = field['offset'].toInt();
+    Expect.isTrue((offset > 0) && (offset < sizeA));
+    maxOffsetA = max(offset, maxOffsetA);
+  }
+
+  Expect.isNotNull(sizeB);
+  Expect.isTrue(sizeB > 0);
+  Expect.isTrue(sizeA <= sizeB);
+  Expect.isTrue(fieldsB.length == 3);
+  for (var field in fieldsB) {
+    String fieldName = field['field'];
+    if (fieldName == 'staticB4') {
+      Expect.isTrue(field['static']);
+    } else {
+      Expect.isTrue(fieldName == 'fieldB1' || fieldName == 'fieldB2');
+      int offset = field['offset'].toInt();
+      Expect.isTrue((offset > 0) && (offset < sizeB));
+      Expect.isTrue(offset > maxOffsetA);
+    }
+  }
+}
+
+main() async {
+  if (!isAOTRuntime) {
+    return; // Running in JIT: AOT binaries not available.
+  }
+
+  if (Platform.isAndroid) {
+    return; // SDK tree not available on the test device.
+  }
+
+  // These are the tools we need to be available to run on a given platform:
+  if (!File(platformDill).existsSync()) {
+    throw "Cannot run test as $platformDill does not exist";
+  }
+  if (!await testExecutable(genSnapshot)) {
+    throw "Cannot run test as $genSnapshot not available";
+  }
+
+  final testScriptUri =
+      Platform.script.resolve('print_object_layout_script.dart');
+
+  await withTempDir('print-object-layout-test', (String temp) async {
+    final appDillPath = path.join(temp, 'app.dill');
+    final snapshotPath = path.join(temp, 'aot.snapshot');
+    final objectLayoutPath = path.join(temp, 'layout.json');
+
+    await run(genKernel, <String>[
+      '--aot',
+      '--platform=$platformDill',
+      '--output=$appDillPath',
+      testScriptUri.toFilePath(),
+    ]);
+
+    await run(genSnapshot, <String>[
+      '--snapshot-kind=app-aot-elf',
+      '--elf=$snapshotPath',
+      '--print-object-layout-to=$objectLayoutPath',
+      appDillPath,
+    ]);
+
+    verifyObjectLayout(objectLayoutPath);
+  });
+}
diff --git a/runtime/tests/vm/dart_2/regress47472_test.dart b/runtime/tests/vm/dart_2/regress47472_test.dart
new file mode 100644
index 0000000..a3f8f8b
--- /dev/null
+++ b/runtime/tests/vm/dart_2/regress47472_test.dart
@@ -0,0 +1,11 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+main() {
+  for (int i = 0; i < 1000000; ++i) {
+    try {
+      throw 'a';
+    } catch (e, s) {}
+  }
+}
diff --git a/runtime/tests/vm/dart_2/regress_36636_test.dart b/runtime/tests/vm/dart_2/regress_36636_test.dart
index 1c41d17..5040d1f 100644
--- a/runtime/tests/vm/dart_2/regress_36636_test.dart
+++ b/runtime/tests/vm/dart_2/regress_36636_test.dart
@@ -4,6 +4,6 @@
 
 // @dart = 2.9
 
-// VMOptions=--intrinsify=false --no-use-vfp
+// VMOptions=--intrinsify=false
 
 main() {}
diff --git a/runtime/tests/vm/dart_2/regress_flutter66765_test.dart b/runtime/tests/vm/dart_2/regress_flutter66765_test.dart
new file mode 100644
index 0000000..af3337c
--- /dev/null
+++ b/runtime/tests/vm/dart_2/regress_flutter66765_test.dart
@@ -0,0 +1,38 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// @dart = 2.9
+
+// Regression test for https://github.com/flutter/flutter/issues/66765
+// Verifies that AOT compiler doesn't crash on a particular flow graph.
+
+class TutorialBloc {
+  TutorialBloc();
+
+  Stream<TutorialStates> mapEventToState(TutorialEvents event) async* {
+    switch (event.action) {
+      default:
+        yield TutorialInitState();
+    }
+  }
+}
+
+enum TutorialAction { dummyData }
+
+class TutorialEvents {
+  final TutorialAction action;
+  const TutorialEvents(this.action);
+}
+
+abstract class TutorialStates {}
+
+class TutorialInitState extends TutorialStates {}
+
+List<dynamic> l = [TutorialBloc()];
+
+void main() async {
+  if (l.length > 1) {
+    l[0].mapEventToState(42);
+  }
+}
diff --git a/runtime/tests/vm/dart_2/slow_path_shared_stub_test.dart b/runtime/tests/vm/dart_2/slow_path_shared_stub_test.dart
index be7b675..9f6cc16 100644
--- a/runtime/tests/vm/dart_2/slow_path_shared_stub_test.dart
+++ b/runtime/tests/vm/dart_2/slow_path_shared_stub_test.dart
@@ -5,7 +5,6 @@
 // @dart = 2.9
 
 // VMOptions=--optimization_counter_threshold=10 --no-background-compilation --shared-slow-path-triggers-gc
-// VMOptions=--optimization_counter_threshold=10 --no-background-compilation --shared-slow-path-triggers-gc --no-use-vfp
 
 // This tests the stackmaps and environments for safepoints corresponding to
 // slow-path code which uses shared runtime stubs.
diff --git a/runtime/tests/vm/dart_2/typed_data_vfp_regress_42745_test.dart b/runtime/tests/vm/dart_2/typed_data_vfp_regress_42745_test.dart
index 77ad067..27f1b23 100644
--- a/runtime/tests/vm/dart_2/typed_data_vfp_regress_42745_test.dart
+++ b/runtime/tests/vm/dart_2/typed_data_vfp_regress_42745_test.dart
@@ -1,7 +1,6 @@
 // Copyright (c) 2020, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
-// VMOptions=--no-use-vfp
 
 // @dart = 2.9
 
diff --git a/runtime/tests/vm/vm.status b/runtime/tests/vm/vm.status
index f4bc06c..0685477 100644
--- a/runtime/tests/vm/vm.status
+++ b/runtime/tests/vm/vm.status
@@ -20,6 +20,7 @@
 dart/isolates/fast_object_copy_test: Pass, Slow # Slow due to doing a lot of transitive object copies.
 dart/minimal_kernel_test: Pass, Slow # Spawns several subprocesses
 dart/null_safety_autodetection_in_kernel_compiler_test: Pass, Slow # Spawns several subprocesses
+dart/print_object_layout_test: Pass, Slow # Spawns several subprocesses
 dart/slow_path_shared_stub_test: Pass, Slow # Uses --shared-slow-path-triggers-gc flag.
 dart/snapshot_version_test: Skip # This test is a Dart1 test (script snapshot)
 dart/stack_overflow_shared_test: Pass, Slow # Uses --shared-slow-path-triggers-gc flag.
@@ -32,6 +33,7 @@
 dart_2/isolates/fast_object_copy_test: Pass, Slow # Slow due to doing a lot of transitive object copies.
 dart_2/minimal_kernel_test: Pass, Slow # Spawns several subprocesses
 dart_2/null_safety_autodetection_in_kernel_compiler_test: Pass, Slow # Spawns several subprocesses
+dart_2/print_object_layout_test: Pass, Slow # Spawns several subprocesses
 dart_2/slow_path_shared_stub_test: Pass, Slow # Uses --shared-slow-path-triggers-gc flag.
 dart_2/snapshot_version_test: Skip # This test is a Dart1 test (script snapshot)
 dart_2/stack_overflow_shared_test: Pass, Slow # Uses --shared-slow-path-triggers-gc flag.
diff --git a/runtime/tools/dartfuzz/dartfuzz_test.dart b/runtime/tools/dartfuzz/dartfuzz_test.dart
index 7ba2f79..b6e32b7 100644
--- a/runtime/tools/dartfuzz/dartfuzz_test.dart
+++ b/runtime/tools/dartfuzz/dartfuzz_test.dart
@@ -78,11 +78,6 @@
         extraFlags += ['--optimization_counter_threshold=1'];
       }
     }
-    // Every once in a while, disable VFP on arm32.
-    if (mode.contains('arm32') && rand.nextInt(4) == 0) {
-      prefix += '-noVFP';
-      extraFlags += ['--no-use-vfp'];
-    }
     // Every once in a while, use -O3 compiler.
     if (!mode.startsWith('djs') && rand.nextInt(4) == 0) {
       prefix += '-O3';
diff --git a/runtime/vm/BUILD.gn b/runtime/vm/BUILD.gn
index 30f1303..9abd6ee 100644
--- a/runtime/vm/BUILD.gn
+++ b/runtime/vm/BUILD.gn
@@ -56,7 +56,10 @@
     if (!is_android) {
       libs += [ "pthread" ]
     }
-    if (!is_mac && !is_ios) {
+
+    # Clang with libc++ does not require an explicit atomic library reference.
+    # (similar to https://github.com/flutter/buildroot/blob/master/build/config/compiler/BUILD.gn#L562)
+    if (!is_clang) {
       libs += [ "atomic" ]
     }
   }
diff --git a/runtime/vm/app_snapshot.cc b/runtime/vm/app_snapshot.cc
index 7a94ef8..de02c85 100644
--- a/runtime/vm/app_snapshot.cc
+++ b/runtime/vm/app_snapshot.cc
@@ -997,7 +997,14 @@
       AutoTraceObjectName(func, MakeDisambiguatedFunctionName(s, func));
       WriteFromTo(func);
       if (kind == Snapshot::kFullAOT) {
-        WriteCompressedField(func, code);
+#if defined(DART_PRECOMPILER)
+        CodePtr code = func->untag()->code();
+        const auto code_index = s->GetCodeIndex(code);
+        s->WriteUnsigned(code_index);
+        s->AttributePropertyRef(code, "code_");
+#else
+        UNREACHABLE();
+#endif
       } else if (s->kind() == Snapshot::kFullJIT) {
         NOT_IN_PRECOMPILED(WriteCompressedField(func, unoptimized_code));
         WriteCompressedField(func, code);
@@ -1038,6 +1045,87 @@
 };
 #endif  // !DART_PRECOMPILED_RUNTIME
 
+template <bool need_entry_point_for_non_discarded>
+DART_FORCE_INLINE static CodePtr GetCodeAndEntryPointByIndex(
+    const Deserializer* d,
+    intptr_t code_index,
+    uword* entry_point) {
+  code_index -= 1;  // 0 is reserved for LazyCompile stub.
+
+  // In root unit and VM isolate snapshot code_indices are self-contained
+  // they point into instruction table and/or into the code cluster.
+  // In non-root units we might also refer to code objects from the
+  // parent unit which means code_index is biased by num_base_objects_
+  const intptr_t base = d->is_non_root_unit() ? d->num_base_objects() : 0;
+  if (code_index < base) {
+    CodePtr code = static_cast<CodePtr>(d->Ref(code_index));
+    if (need_entry_point_for_non_discarded) {
+      *entry_point = Code::EntryPointOf(code);
+    }
+    return code;
+  }
+  code_index -= base;
+
+  // At this point code_index is refering to a code object which is either
+  // discarded or exists in the Code cluster. Non-discarded Code objects
+  // are associated with the tail of the instruction table and have the
+  // same order there and in the Code cluster. This means that
+  // subtracting first_entry_with_code yields index into the Code cluster.
+  // This also works for deferred code objects in root unit's snapshot
+  // due to the choice of encoding (see Serializer::GetCodeIndex).
+  const intptr_t first_entry_with_code =
+      d->instructions_table().rodata()->first_entry_with_code;
+  if (code_index < first_entry_with_code) {
+    *entry_point = d->instructions_table().EntryPointAt(code_index);
+    return StubCode::UnknownDartCode().ptr();
+  } else {
+    const intptr_t cluster_index = code_index - first_entry_with_code;
+    CodePtr code =
+        static_cast<CodePtr>(d->Ref(d->code_start_index() + cluster_index));
+    if (need_entry_point_for_non_discarded) {
+      *entry_point = Code::EntryPointOf(code);
+    }
+    return code;
+  }
+}
+
+CodePtr Deserializer::GetCodeByIndex(intptr_t code_index,
+                                     uword* entry_point) const {
+  // See Serializer::GetCodeIndex for how code_index is encoded.
+  if (code_index == 0) {
+    return StubCode::LazyCompile().ptr();
+  } else if (FLAG_precompiled_mode) {
+    return GetCodeAndEntryPointByIndex<
+        /*need_entry_point_for_non_discarded=*/false>(this, code_index,
+                                                      entry_point);
+  } else {
+    // -1 below because 0 is reserved for LazyCompile stub.
+    const intptr_t ref = code_start_index_ + code_index - 1;
+    ASSERT(code_start_index_ <= ref && ref < code_stop_index_);
+    return static_cast<CodePtr>(Ref(ref));
+  }
+}
+
+intptr_t Deserializer::CodeIndexToClusterIndex(const InstructionsTable& table,
+                                               intptr_t code_index) {
+  // Note: code indices we are interpreting here originate from the root
+  // loading unit which means base is equal to 0.
+  // See comments which clarify the connection between code_index and
+  // index into the Code cluster.
+  ASSERT(FLAG_precompiled_mode);
+  const intptr_t first_entry_with_code = table.rodata()->first_entry_with_code;
+  return code_index - 1 - first_entry_with_code;
+}
+
+uword Deserializer::GetEntryPointByCodeIndex(intptr_t code_index) const {
+  // See Deserializer::GetCodeByIndex which this code repeats.
+  ASSERT(FLAG_precompiled_mode);
+  uword entry_point = 0;
+  GetCodeAndEntryPointByIndex</*need_entry_point_for_non_discarded=*/true>(
+      this, code_index, &entry_point);
+  return entry_point;
+}
+
 class FunctionDeserializationCluster : public DeserializationCluster {
  public:
   FunctionDeserializationCluster() : DeserializationCluster("Function") {}
@@ -1064,11 +1152,10 @@
 
       if (kind == Snapshot::kFullAOT) {
         const intptr_t code_index = d->ReadUnsigned();
-        CodePtr code = static_cast<CodePtr>(d->Ref(code_index));
+        uword entry_point = 0;
+        CodePtr code = d->GetCodeByIndex(code_index, &entry_point);
         func->untag()->code_ = code;
-        if (Code::IsUnknownDartCode(code)) {
-          const uword entry_point = d->instructions_table().EntryPointAt(
-              code_index - d->code_start_index());
+        if (entry_point != 0) {
           func->untag()->entry_point_ = entry_point;
           func->untag()->unchecked_entry_point_ = entry_point;
         }
@@ -1788,7 +1875,11 @@
     if (s->kind() == Snapshot::kFullJIT) {
       s->Push(code->untag()->deopt_info_array_);
       s->Push(code->untag()->static_calls_target_table_);
+      s->Push(code->untag()->compressed_stackmaps_);
     } else if (s->kind() == Snapshot::kFullAOT) {
+      // Note: we don't trace compressed_stackmaps_ because we are going to emit
+      // a separate mapping table into RO data which is not going to be a real
+      // heap object.
 #if defined(DART_PRECOMPILER)
       auto const calls_array = code->untag()->static_calls_target_table_;
       if (calls_array != Array::null()) {
@@ -1819,10 +1910,6 @@
 #endif
     }
 
-    if (s->InCurrentLoadingUnitOrRoot(code->untag()->compressed_stackmaps_)) {
-      s->Push(code->untag()->compressed_stackmaps_);
-    }
-
     if (Code::IsDiscarded(code)) {
       ASSERT(s->kind() == Snapshot::kFullAOT && FLAG_dwarf_stack_traces_mode &&
              !FLAG_retain_code_objects);
@@ -1869,50 +1956,60 @@
 
   struct CodeOrderInfo {
     CodePtr code;
-    intptr_t order;
-    intptr_t original_index;
+    intptr_t not_discarded;  // 1 if this code was not discarded and
+                             // 0 otherwise.
+    intptr_t instructions_id;
   };
 
   // We sort code objects in such a way that code objects with the same
-  // instructions are grouped together. To make sorting more stable between
-  // similar programs we also sort them further by their original indices -
-  // this helps to stabilize output of --print-instructions-sizes-to which uses
-  // the name of the first code object (among those pointing to the same
-  // instruction objects).
+  // instructions are grouped together and ensure that all instructions
+  // without associated code objects are grouped together at the beginning of
+  // the code section. InstructionsTable encoding assumes that all
+  // instructions with non-discarded Code objects are grouped at the end.
+  //
+  // Note that in AOT mode we expect that all Code objects pointing to
+  // the same instructions are deduplicated, as in bare instructions mode
+  // there is no way to identify which specific Code object (out of those
+  // which point to the specific instructions range) actually corresponds
+  // to a particular frame.
   static int CompareCodeOrderInfo(CodeOrderInfo const* a,
                                   CodeOrderInfo const* b) {
-    if (a->order < b->order) return -1;
-    if (a->order > b->order) return 1;
-    if (a->original_index < b->original_index) return -1;
-    if (a->original_index > b->original_index) return 1;
+    if (a->not_discarded < b->not_discarded) return -1;
+    if (a->not_discarded > b->not_discarded) return 1;
+    if (a->instructions_id < b->instructions_id) return -1;
+    if (a->instructions_id > b->instructions_id) return 1;
     return 0;
   }
 
-  static void Insert(GrowableArray<CodeOrderInfo>* order_list,
+  static void Insert(Serializer* s,
+                     GrowableArray<CodeOrderInfo>* order_list,
                      IntMap<intptr_t>* order_map,
-                     CodePtr code,
-                     intptr_t original_index) {
+                     CodePtr code) {
     InstructionsPtr instr = code->untag()->instructions_;
     intptr_t key = static_cast<intptr_t>(instr);
-    intptr_t order;
+    intptr_t instructions_id = 0;
+
     if (order_map->HasKey(key)) {
-      order = order_map->Lookup(key);
+      // We are expected to merge code objects which point to the same
+      // instructions in the precompiled mode.
+      RELEASE_ASSERT(!FLAG_precompiled_mode);
+      instructions_id = order_map->Lookup(key);
     } else {
-      order = order_list->length() + 1;
-      order_map->Insert(key, order);
+      instructions_id = order_map->Length() + 1;
+      order_map->Insert(key, instructions_id);
     }
     CodeOrderInfo info;
     info.code = code;
-    info.order = order;
-    info.original_index = original_index;
+    info.instructions_id = instructions_id;
+    info.not_discarded = Code::IsDiscarded(code) ? 0 : 1;
     order_list->Add(info);
   }
 
-  static void Sort(GrowableArray<CodePtr>* codes) {
+  static void Sort(Serializer* s, GrowableArray<CodePtr>* codes) {
     GrowableArray<CodeOrderInfo> order_list;
     IntMap<intptr_t> order_map;
     for (intptr_t i = 0; i < codes->length(); i++) {
-      Insert(&order_list, &order_map, (*codes)[i], i);
+      Insert(s, &order_list, &order_map, (*codes)[i]);
     }
     order_list.Sort(CompareCodeOrderInfo);
     ASSERT(order_list.length() == codes->length());
@@ -1921,11 +2018,11 @@
     }
   }
 
-  static void Sort(GrowableArray<Code*>* codes) {
+  static void Sort(Serializer* s, GrowableArray<Code*>* codes) {
     GrowableArray<CodeOrderInfo> order_list;
     IntMap<intptr_t> order_map;
     for (intptr_t i = 0; i < codes->length(); i++) {
-      Insert(&order_list, &order_map, (*codes)[i]->ptr(), i);
+      Insert(s, &order_list, &order_map, (*codes)[i]->ptr());
     }
     order_list.Sort(CompareCodeOrderInfo);
     ASSERT(order_list.length() == codes->length());
@@ -1934,27 +2031,49 @@
     }
   }
 
+  intptr_t NonDiscardedCodeCount() {
+    intptr_t count = 0;
+    for (auto code : objects_) {
+      if (!Code::IsDiscarded(code)) {
+        count++;
+      }
+    }
+    return count;
+  }
+
   void WriteAlloc(Serializer* s) {
+    const intptr_t non_discarded_count = NonDiscardedCodeCount();
     const intptr_t count = objects_.length();
-    s->WriteUnsigned(count);
-    for (intptr_t i = 0; i < count; i++) {
-      WriteAlloc(s, objects_[i]);
+    ASSERT(count == non_discarded_count || (s->kind() == Snapshot::kFullAOT));
+
+    first_ref_ = s->next_ref_index();
+    s->WriteUnsigned(non_discarded_count);
+    for (auto code : objects_) {
+      if (!Code::IsDiscarded(code)) {
+        WriteAlloc(s, code);
+      } else {
+        // Mark discarded code unreachable, so that we could later
+        // assign artificial references to it.
+        s->heap()->SetObjectId(code, kUnreachableReference);
+      }
     }
-    const intptr_t deferred_count = deferred_objects_.length();
-    s->WriteUnsigned(deferred_count);
-    for (intptr_t i = 0; i < deferred_count; i++) {
-      WriteAlloc(s, deferred_objects_[i]);
+
+    s->WriteUnsigned(deferred_objects_.length());
+    first_deferred_ref_ = s->next_ref_index();
+    for (auto code : deferred_objects_) {
+      ASSERT(!Code::IsDiscarded(code));
+      WriteAlloc(s, code);
     }
+    last_ref_ = s->next_ref_index() - 1;
   }
 
   void WriteAlloc(Serializer* s, CodePtr code) {
+    ASSERT(!Code::IsDiscarded(code));
     s->AssignRef(code);
     AutoTraceObjectName(code, MakeDisambiguatedCodeName(s, code));
     const int32_t state_bits = code->untag()->state_bits_;
     s->Write<int32_t>(state_bits);
-    if (!Code::DiscardedBit::decode(state_bits)) {
-      target_memory_size_ += compiler::target::Code::InstanceSize(0);
-    }
+    target_memory_size_ += compiler::target::Code::InstanceSize(0);
   }
 
   void WriteFill(Serializer* s) {
@@ -1962,12 +2081,20 @@
     const intptr_t count = objects_.length();
     for (intptr_t i = 0; i < count; i++) {
       CodePtr code = objects_[i];
-      WriteFill(s, kind, code, false);
+#if defined(DART_PRECOMPILER)
+      if (FLAG_write_v8_snapshot_profile_to != nullptr &&
+          Code::IsDiscarded(code)) {
+        s->CreateArtificialNodeIfNeeded(code);
+      }
+#endif
+      // Note: for discarded code this function will not write anything out
+      // it is only called to produce information into snapshot profile.
+      WriteFill(s, kind, code, /*deferred=*/false);
     }
     const intptr_t deferred_count = deferred_objects_.length();
     for (intptr_t i = 0; i < deferred_count; i++) {
       CodePtr code = deferred_objects_[i];
-      WriteFill(s, kind, code, true);
+      WriteFill(s, kind, code, /*deferred=*/true);
     }
   }
 
@@ -1975,6 +2102,7 @@
                  Snapshot::Kind kind,
                  CodePtr code,
                  bool deferred) {
+    const intptr_t bytes_written = s->bytes_written();
     AutoTraceObjectName(code, MakeDisambiguatedCodeName(s, code));
 
     intptr_t pointer_offsets_length =
@@ -2024,6 +2152,8 @@
 #endif  // defined(DART_PRECOMPILER)
 
     if (Code::IsDiscarded(code)) {
+      // No bytes should be written to represent this code.
+      ASSERT(s->bytes_written() == bytes_written);
       // Only write instructions, compressed stackmaps and state bits
       // for the discarded Code objects.
       ASSERT(kind == Snapshot::kFullAOT && FLAG_dwarf_stack_traces_mode &&
@@ -2036,7 +2166,6 @@
         s->AttributePropertyRef(owner, "owner_");
       }
 #endif
-
       return;
     }
 
@@ -2053,10 +2182,8 @@
     WriteField(code, exception_handlers_);
     WriteField(code, pc_descriptors_);
     WriteField(code, catch_entry_);
-    if (s->InCurrentLoadingUnitOrRoot(code->untag()->compressed_stackmaps_)) {
+    if (s->kind() == Snapshot::kFullJIT) {
       WriteField(code, compressed_stackmaps_);
-    } else {
-      WriteFieldValue(compressed_stackmaps_, CompressedStackMaps::null());
     }
     if (FLAG_precompiled_mode && FLAG_dwarf_stack_traces_mode) {
       WriteFieldValue(inlined_id_to_function_, Array::null());
@@ -2098,7 +2225,14 @@
             Object::NameVisibility::kInternalName));
   }
 
+  intptr_t first_ref() const { return first_ref_; }
+  intptr_t first_deferred_ref() const { return first_deferred_ref_; }
+  intptr_t last_ref() const { return last_ref_; }
+
  private:
+  intptr_t first_ref_;
+  intptr_t first_deferred_ref_;
+  intptr_t last_ref_;
   GrowableArray<CodePtr> objects_;
   GrowableArray<CodePtr> deferred_objects_;
   Array& array_;
@@ -2119,6 +2253,7 @@
       ReadAllocOneCode(d, old_space);
     }
     stop_index_ = d->next_index();
+    d->set_code_stop_index(stop_index_);
     deferred_start_index_ = d->next_index();
     const intptr_t deferred_count = d->ReadUnsigned();
     for (intptr_t i = 0; i < deferred_count; i++) {
@@ -2129,15 +2264,11 @@
 
   void ReadAllocOneCode(Deserializer* d, PageSpace* old_space) {
     const int32_t state_bits = d->Read<int32_t>();
-    if (Code::DiscardedBit::decode(state_bits)) {
-      ASSERT(StubCode::HasBeenInitialized());
-      d->AssignRef(StubCode::UnknownDartCode().ptr());
-    } else {
-      auto code = static_cast<CodePtr>(
-          old_space->AllocateSnapshot(Code::InstanceSize(0)));
-      d->AssignRef(code);
-      code->untag()->state_bits_ = state_bits;
-    }
+    ASSERT(!Code::DiscardedBit::decode(state_bits));
+    auto code = static_cast<CodePtr>(
+        old_space->AllocateSnapshot(Code::InstanceSize(0)));
+    d->AssignRef(code);
+    code->untag()->state_bits_ = state_bits;
   }
 
   void ReadFill(Deserializer* d, bool primary) {
@@ -2153,17 +2284,12 @@
   void ReadFill(Deserializer* d, intptr_t id, bool deferred) {
     auto const code = static_cast<CodePtr>(d->Ref(id));
 
-#if defined(DART_PRECOMPILED_RUNTIME)
-    if (Code::IsUnknownDartCode(code)) {
-      d->ReadInstructions(code, deferred, /*discarded=*/true);
-      return;
-    }
-#endif  // defined(DART_PRECOMPILED_RUNTIME)
+    ASSERT(!Code::IsUnknownDartCode(code));
 
     Deserializer::InitializeHeader(code, kCodeCid, Code::InstanceSize(0));
     ASSERT(!Code::IsDiscarded(code));
 
-    d->ReadInstructions(code, deferred, /*discarded=*/false);
+    d->ReadInstructions(code, deferred);
 
     // There would be a single global pool if this is a full AOT snapshot
     // with bare instructions.
@@ -2178,8 +2304,12 @@
     code->untag()->pc_descriptors_ =
         static_cast<PcDescriptorsPtr>(d->ReadRef());
     code->untag()->catch_entry_ = d->ReadRef();
-    code->untag()->compressed_stackmaps_ =
-        static_cast<CompressedStackMapsPtr>(d->ReadRef());
+    if (d->kind() == Snapshot::kFullJIT) {
+      code->untag()->compressed_stackmaps_ =
+          static_cast<CompressedStackMapsPtr>(d->ReadRef());
+    } else if (d->kind() == Snapshot::kFullAOT) {
+      code->untag()->compressed_stackmaps_ = CompressedStackMaps::null();
+    }
     code->untag()->inlined_id_to_function_ =
         static_cast<ArrayPtr>(d->ReadRef());
     code->untag()->code_source_map_ =
@@ -2690,7 +2820,7 @@
       s->AssignRef(map);
       AutoTraceObject(map);
       const intptr_t length = UntaggedCompressedStackMaps::SizeField::decode(
-          map->untag()->flags_and_size_);
+          map->untag()->payload()->flags_and_size);
       s->WriteUnsigned(length);
       target_memory_size_ +=
           compiler::target::CompressedStackMaps::InstanceSize(length);
@@ -2702,10 +2832,11 @@
     for (intptr_t i = 0; i < count; i++) {
       CompressedStackMapsPtr map = objects_[i];
       AutoTraceObject(map);
-      s->WriteUnsigned(map->untag()->flags_and_size_);
+      s->WriteUnsigned(map->untag()->payload()->flags_and_size);
       const intptr_t length = UntaggedCompressedStackMaps::SizeField::decode(
-          map->untag()->flags_and_size_);
-      uint8_t* cdata = reinterpret_cast<uint8_t*>(map->untag()->data());
+          map->untag()->payload()->flags_and_size);
+      uint8_t* cdata =
+          reinterpret_cast<uint8_t*>(map->untag()->payload()->data());
       s->WriteBytes(cdata, length);
     }
   }
@@ -2743,8 +2874,9 @@
           static_cast<CompressedStackMapsPtr>(d->Ref(id));
       Deserializer::InitializeHeader(map, kCompressedStackMapsCid,
                                      CompressedStackMaps::InstanceSize(length));
-      map->untag()->flags_and_size_ = flags_and_size;
-      uint8_t* cdata = reinterpret_cast<uint8_t*>(map->untag()->data());
+      map->untag()->payload()->flags_and_size = flags_and_size;
+      uint8_t* cdata =
+          reinterpret_cast<uint8_t*>(map->untag()->payload()->data());
       d->ReadBytes(cdata, length);
     }
   }
@@ -5690,7 +5822,9 @@
   V(canonical_type_parameters, Array,                                          \
     HashTables::New<CanonicalTypeParameterSet>(4))                             \
   ONLY_IN_PRODUCT(ONLY_IN_AOT(                                                 \
-      V(closure_functions, GrowableObjectArray, GrowableObjectArray::null())))
+      V(closure_functions, GrowableObjectArray, GrowableObjectArray::null()))) \
+  ONLY_IN_AOT(V(canonicalized_stack_map_entries, CompressedStackMaps,          \
+                CompressedStackMaps::null()))
 
   ProgramSerializationRoots(ZoneGrowableArray<Object*>* base_objects,
                             ObjectStore* object_store,
@@ -5774,6 +5908,10 @@
     s->WriteDispatchTable(dispatch_table_entries_);
   }
 
+  virtual const CompressedStackMaps& canonicalized_stack_map_entries() const {
+    return saved_canonicalized_stack_map_entries_;
+  }
+
  private:
   ZoneGrowableArray<Object*>* const base_objects_;
   ObjectStore* const object_store_;
@@ -5852,9 +5990,7 @@
   }
 
   void PushRoots(Serializer* s) {
-    intptr_t num_deferred_objects = unit_->deferred_objects()->length();
-    for (intptr_t i = 0; i < num_deferred_objects; i++) {
-      const Object* deferred_object = (*unit_->deferred_objects())[i];
+    for (auto deferred_object : *unit_->deferred_objects()) {
       ASSERT(deferred_object->IsCode());
       CodePtr code = static_cast<CodePtr>(deferred_object->ptr());
       ObjectPoolPtr pool = code->untag()->object_pool_;
@@ -5868,7 +6004,6 @@
           }
         }
       }
-      s->Push(code->untag()->compressed_stackmaps_);
       s->Push(code->untag()->code_source_map_);
     }
   }
@@ -5891,7 +6026,6 @@
       ASSERT(!Code::IsDiscarded(code));
       s->WriteInstructions(code->untag()->instructions_,
                            code->untag()->unchecked_offset_, code, false);
-      s->WriteRootRef(code->untag()->compressed_stackmaps_, "deferred-code");
       s->WriteRootRef(code->untag()->code_source_map_, "deferred-code");
     }
 
@@ -5940,7 +6074,7 @@
     for (intptr_t id = deferred_start_index_; id < deferred_stop_index_; id++) {
       CodePtr code = static_cast<CodePtr>(d->Ref(id));
       ASSERT(!Code::IsUnknownDartCode(code));
-      d->ReadInstructions(code, /*deferred=*/false, /*discarded=*/false);
+      d->ReadInstructions(code, /*deferred=*/false);
       if (code->untag()->owner_->IsHeapObject() &&
           code->untag()->owner_->IsFunction()) {
         FunctionPtr func = static_cast<FunctionPtr>(code->untag()->owner_);
@@ -5964,8 +6098,6 @@
         }
 #endif
       }
-      code->untag()->compressed_stackmaps_ =
-          static_cast<CompressedStackMapsPtr>(d->ReadRef());
       code->untag()->code_source_map_ =
           static_cast<CodeSourceMapPtr>(d->ReadRef());
     }
@@ -5988,8 +6120,12 @@
     if (isolate_group->dispatch_table_snapshot() != nullptr) {
       ReadStream stream(isolate_group->dispatch_table_snapshot(),
                         isolate_group->dispatch_table_snapshot_size());
-      d->ReadDispatchTable(&stream, /*deferred=*/true, deferred_start_index_,
-                           deferred_stop_index_);
+      const GrowableObjectArray& tables = GrowableObjectArray::Handle(
+          isolate_group->object_store()->instructions_tables());
+      InstructionsTable& root_table = InstructionsTable::Handle();
+      root_table ^= tables.At(0);
+      d->ReadDispatchTable(&stream, /*deferred=*/true, root_table,
+                           deferred_start_index_, deferred_stop_index_);
     }
   }
 
@@ -6028,7 +6164,6 @@
       num_base_objects_(0),
       num_written_objects_(0),
       next_ref_index_(kFirstReference),
-      previous_text_offset_(0),
       initial_field_table_(thread->isolate_group()->initial_field_table()),
       vm_(vm),
       profile_writer_(profile_writer)
@@ -6065,7 +6200,13 @@
 void Serializer::AddBaseObject(ObjectPtr base_object,
                                const char* type,
                                const char* name) {
-  AssignRef(base_object);
+  // Don't assign references to the discarded code.
+  const bool is_discarded_code = base_object->IsHeapObject() &&
+                                 base_object->IsCode() &&
+                                 Code::IsDiscarded(Code::RawCast(base_object));
+  if (!is_discarded_code) {
+    AssignRef(base_object);
+  }
   num_base_objects_++;
 
   if ((profile_writer_ != nullptr) && (type != nullptr)) {
@@ -6554,6 +6695,10 @@
     case kStringCid:
       return new (Z) StringSerializationCluster(
           is_canonical, cluster_represents_canonical_set && !vm_);
+#define CASE_FFI_CID(name) case kFfi##name##Cid:
+      CLASS_LIST_FFI_TYPE_MARKER(CASE_FFI_CID)
+#undef CASE_FFI_CID
+      return new (Z) InstanceSerializationCluster(is_canonical, cid);
     case kWeakSerializationReferenceCid:
 #if defined(DART_PRECOMPILER)
       ASSERT(kind_ == Snapshot::kFullAOT);
@@ -6589,8 +6734,100 @@
 }
 
 #if !defined(DART_PRECOMPILED_RUNTIME)
-intptr_t Serializer::PrepareInstructions() {
-  if (!Snapshot::IncludesCode(kind())) return 0;
+#if defined(DART_PRECOMPILER)
+// We use the following encoding schemes when encoding references to Code
+// objects.
+//
+// In AOT mode:
+//
+// 0        --  LazyCompile stub
+// 1        -+
+//           |  for non-root-unit/non-VM snapshots
+// ...        > reference into parent snapshot objects
+//           |  (base is num_base_objects_ in this case, 0 otherwise).
+// base     -+
+// base + 1 -+
+//           |  for non-deferred Code objects (those with instructions)
+//            > index in into the instructions table (code_index_).
+//           |  (L is code_index_.Length()).
+// base + L -+
+// ...      -+
+//           |  for deferred Code objects (those without instructions)
+//            > index of this Code object in the deferred part of the
+//           |  Code cluster.
+//
+// Note that this encoding has the following property: non-discarded
+// non-deferred Code objects form the tail of the instruction table
+// which makes indices assigned to non-discarded non-deferred Code objects
+// and deferred Code objects continuous. This means when decoding
+// code_index - (base + 1) - first_entry_with_code yields an index of the
+// Code object in the Code cluster both for non-deferred and deferred
+// Code objects.
+//
+// For JIT snapshots we do:
+//
+// 0        --  LazyCompile stub
+// 1        -+
+//           |
+// ...        > index of the Code object in the Code cluster.
+//           |
+//
+intptr_t Serializer::GetCodeIndex(CodePtr code) {
+  // In the precompiled mode Code object is uniquely identified by its
+  // instructions (because ProgramVisitor::DedupInstructions will dedup Code
+  // objects with the same instructions).
+  if (code == StubCode::LazyCompile().ptr() && !vm_) {
+    return 0;
+  } else if (FLAG_precompiled_mode) {
+    const intptr_t ref = heap_->GetObjectId(code);
+    ASSERT(!IsReachableReference(ref) == Code::IsDiscarded(code));
+
+    const intptr_t base =
+        (vm_ || current_loading_unit_id() == LoadingUnit::kRootId)
+            ? 0
+            : num_base_objects_;
+
+    // Check if we are referring to the Code object which originates from the
+    // parent loading unit. In this case we write out the reference of this
+    // object.
+    if (!Code::IsDiscarded(code) && ref < base) {
+      RELEASE_ASSERT(current_loading_unit_id() != LoadingUnit::kRootId);
+      return 1 + ref;
+    }
+
+    // Otherwise the code object must either be discarded or originate from
+    // the Code cluster.
+    ASSERT(Code::IsDiscarded(code) || (code_cluster_->first_ref() <= ref &&
+                                       ref <= code_cluster_->last_ref()));
+
+    // If Code object is non-deferred then simply write out the index of the
+    // entry point, otherwise write out the index of the deferred code object.
+    if (ref < code_cluster_->first_deferred_ref()) {
+      const intptr_t key = static_cast<intptr_t>(code->untag()->instructions_);
+      ASSERT(code_index_.HasKey(key));
+      const intptr_t result = code_index_.Lookup(key);
+      ASSERT(0 < result && result <= code_index_.Length());
+      // Note: result already has + 1.
+      return base + result;
+    } else {
+      // Note: only root snapshot can have deferred Code objects in the
+      // cluster.
+      const intptr_t cluster_index = ref - code_cluster_->first_deferred_ref();
+      return 1 + base + code_index_.Length() + cluster_index;
+    }
+  } else {
+    const intptr_t ref = heap_->GetObjectId(code);
+    ASSERT(IsAllocatedReference(ref));
+    ASSERT(code_cluster_->first_ref() <= ref &&
+           ref <= code_cluster_->last_ref());
+    return 1 + (ref - code_cluster_->first_ref());
+  }
+}
+#endif  // defined(DART_PRECOMPILER)
+
+void Serializer::PrepareInstructions(
+    const CompressedStackMaps& canonical_stack_map_entries) {
+  if (!Snapshot::IncludesCode(kind())) return;
 
   // Code objects that have identical/duplicate instructions must be adjacent in
   // the order that Code objects are written because the encoding of the
@@ -6599,14 +6836,14 @@
   // that allows for mapping return addresses back to Code objects depends on
   // this sorting.
   if (code_cluster_ != nullptr) {
-    CodeSerializationCluster::Sort(code_cluster_->objects());
+    CodeSerializationCluster::Sort(this, code_cluster_->objects());
   }
   if ((loading_units_ != nullptr) &&
       (current_loading_unit_id_ == LoadingUnit::kRootId)) {
     for (intptr_t i = LoadingUnit::kRootId + 1; i < loading_units_->length();
          i++) {
       auto unit_objects = loading_units_->At(i)->deferred_objects();
-      CodeSerializationCluster::Sort(unit_objects);
+      CodeSerializationCluster::Sort(this, unit_objects);
       ASSERT(unit_objects->length() == 0 || code_cluster_ != nullptr);
       for (intptr_t j = 0; j < unit_objects->length(); j++) {
         code_cluster_->deferred_objects()->Add(unit_objects->At(j)->ptr());
@@ -6640,10 +6877,165 @@
     GrowableArray<ImageWriterCommand> writer_commands;
     RelocateCodeObjects(vm_, &code_objects, &writer_commands);
     image_writer_->PrepareForSerialization(&writer_commands);
-    return code_objects.length();
+
+    if (code_objects.length() == 0) {
+      return;
+    }
+
+    // Build UntaggedInstructionsTable::Data object to be added to the
+    // read-only data section of the snapshot. It contains:
+    //
+    //    - a binary search table mapping an Instructions entry point to its
+    //      stack maps (by offset from the beginning of the Data object);
+    //    - followed by stack maps bytes;
+    //    - followed by canonical stack map entries.
+    //
+    struct StackMapInfo : public ZoneAllocated {
+      CompressedStackMapsPtr map;
+      intptr_t use_count;
+      uint32_t offset;
+    };
+
+    GrowableArray<StackMapInfo*> stack_maps;
+    IntMap<StackMapInfo*> stack_maps_info;
+
+    // Build code_index_ (which maps Instructions object to the order in
+    // which they appear in the code section in the end) and collect all
+    // stack maps.
+    // We also find the first Instructions object which is going to have
+    // Code object associated with it. This will allow to reduce the binary
+    // search space when searching specifically for the code object in runtime.
+    uint32_t total = 0;
+    intptr_t not_discarded_count = 0;
+    uint32_t first_entry_with_code = 0;
+    for (auto& cmd : writer_commands) {
+      if (cmd.op == ImageWriterCommand::InsertInstructionOfCode) {
+        RELEASE_ASSERT(code_objects[total] ==
+                       cmd.insert_instruction_of_code.code);
+        ASSERT(!Code::IsDiscarded(cmd.insert_instruction_of_code.code) ||
+               (not_discarded_count == 0));
+        if (!Code::IsDiscarded(cmd.insert_instruction_of_code.code)) {
+          if (not_discarded_count == 0) {
+            first_entry_with_code = total;
+          }
+          not_discarded_count++;
+        }
+        total++;
+
+        // Update code_index_.
+        {
+          const intptr_t instr = static_cast<intptr_t>(
+              cmd.insert_instruction_of_code.code->untag()->instructions_);
+          ASSERT(!code_index_.HasKey(instr));
+          code_index_.Insert(instr, total);
+        }
+
+        // Collect stack maps.
+        CompressedStackMapsPtr stack_map =
+            cmd.insert_instruction_of_code.code->untag()->compressed_stackmaps_;
+        const intptr_t key = static_cast<intptr_t>(stack_map);
+
+        if (stack_maps_info.HasKey(key)) {
+          stack_maps_info.Lookup(key)->use_count++;
+        } else {
+          auto info = new StackMapInfo();
+          info->map = stack_map;
+          info->use_count = 1;
+          stack_maps.Add(info);
+          stack_maps_info.Insert(key, info);
+        }
+      }
+    }
+    ASSERT(static_cast<intptr_t>(total) == code_index_.Length());
+    instructions_table_len_ = not_discarded_count;
+
+    // Sort stack maps by usage so that most commonly used stack maps are
+    // together at the start of the Data object.
+    stack_maps.Sort([](StackMapInfo* const* a, StackMapInfo* const* b) {
+      if ((*a)->use_count < (*b)->use_count) return 1;
+      if ((*a)->use_count > (*b)->use_count) return -1;
+      return 0;
+    });
+
+    // Build Data object.
+    MallocWriteStream pc_mapping(4 * KB);
+
+    // Write the header out.
+    {
+      UntaggedInstructionsTable::Data header;
+      memset(&header, 0, sizeof(header));
+      header.length = total;
+      header.first_entry_with_code = first_entry_with_code;
+      pc_mapping.WriteFixed<UntaggedInstructionsTable::Data>(header);
+    }
+
+    // Reserve space for the binary search table.
+    for (auto& cmd : writer_commands) {
+      if (cmd.op == ImageWriterCommand::InsertInstructionOfCode) {
+        pc_mapping.WriteFixed<UntaggedInstructionsTable::DataEntry>({0, 0});
+      }
+    }
+
+    // Now write collected stack maps after the binary search table.
+    auto write_stack_map = [&](CompressedStackMapsPtr smap) {
+      const auto flags_and_size = smap->untag()->payload()->flags_and_size;
+      const auto payload_size =
+          UntaggedCompressedStackMaps::SizeField::decode(flags_and_size);
+      pc_mapping.WriteFixed<uint32_t>(flags_and_size);
+      pc_mapping.WriteBytes(smap->untag()->payload()->data(), payload_size);
+    };
+
+    for (auto sm : stack_maps) {
+      sm->offset = pc_mapping.bytes_written();
+      write_stack_map(sm->map);
+    }
+
+    // Write canonical entries (if any).
+    if (!canonical_stack_map_entries.IsNull()) {
+      auto header = reinterpret_cast<UntaggedInstructionsTable::Data*>(
+          pc_mapping.buffer());
+      header->canonical_stack_map_entries_offset = pc_mapping.bytes_written();
+      write_stack_map(canonical_stack_map_entries.ptr());
+    }
+    const auto total_bytes = pc_mapping.bytes_written();
+
+    // Now that we have offsets to all stack maps we can write binary
+    // search table.
+    pc_mapping.SetPosition(
+        sizeof(UntaggedInstructionsTable::Data));  // Skip the header.
+    for (auto& cmd : writer_commands) {
+      if (cmd.op == ImageWriterCommand::InsertInstructionOfCode) {
+        CompressedStackMapsPtr smap =
+            cmd.insert_instruction_of_code.code->untag()->compressed_stackmaps_;
+        const auto offset =
+            stack_maps_info.Lookup(static_cast<intptr_t>(smap))->offset;
+        const auto entry = image_writer_->GetTextOffsetFor(
+            Code::InstructionsOf(cmd.insert_instruction_of_code.code),
+            cmd.insert_instruction_of_code.code);
+
+        pc_mapping.WriteFixed<UntaggedInstructionsTable::DataEntry>(
+            {static_cast<uint32_t>(entry), offset});
+      }
+    }
+    // Restore position so that Steal does not truncate the buffer.
+    pc_mapping.SetPosition(total_bytes);
+
+    intptr_t length = 0;
+    uint8_t* bytes = pc_mapping.Steal(&length);
+
+    instructions_table_rodata_offset_ =
+        image_writer_->AddBytesToData(bytes, length);
+    // Attribute all bytes in this object to the root for simplicity.
+    if (profile_writer_ != nullptr) {
+      const auto offset_space = vm_ ? IdSpace::kVmData : IdSpace::kIsolateData;
+      profile_writer_->AttributeReferenceTo(
+          V8SnapshotProfileWriter::kArtificialRootId,
+          V8SnapshotProfileWriter::Reference::Property(
+              "<instructions-table-rodata>"),
+          {offset_space, instructions_table_rodata_offset_});
+    }
   }
 #endif  // defined(DART_PRECOMPILER) && !defined(TARGET_ARCH_IA32)
-  return 0;
 }
 
 void Serializer::WriteInstructions(InstructionsPtr instr,
@@ -6669,25 +7061,16 @@
         {offset_space, offset});
   }
 
+  if (Code::IsDiscarded(code)) {
+    // Discarded Code objects are not supported in the vm isolate snapshot.
+    ASSERT(!vm_);
+    return;
+  }
+
   if (FLAG_precompiled_mode) {
-    ASSERT(offset != 0);
-    RELEASE_ASSERT(offset >= previous_text_offset_);
-    const uint32_t delta = offset - previous_text_offset_;
-    WriteUnsigned(delta);
     const uint32_t payload_info =
         (unchecked_offset << 1) | (Code::HasMonomorphicEntry(code) ? 0x1 : 0x0);
     WriteUnsigned(payload_info);
-    previous_text_offset_ = offset;
-
-    if (Code::IsDiscarded(code)) {
-      // Discarded Code objects are not supported in the vm isolate snapshot.
-      ASSERT(!vm_);
-      // Stack maps of discarded Code objects are written along with
-      // instructions so they can be added to instructions table during
-      // deserialization.
-      WritePropertyRef(code->untag()->compressed_stackmaps_,
-                       "compressed_stackmaps_");
-    }
     return;
   }
 #endif
@@ -6718,11 +7101,11 @@
   }
   return image_writer_->data_size();
 }
-#endif
+#endif  // !defined(DART_PRECOMPILED_RUNTIME)
 
 void Serializer::Push(ObjectPtr object) {
-  if (object->IsHeapObject() && object->IsCode() &&
-      !Snapshot::IncludesCode(kind_)) {
+  const bool is_code = object->IsHeapObject() && object->IsCode();
+  if (is_code && !Snapshot::IncludesCode(kind_)) {
     return;  // Do not trace, will write null.
   }
 
@@ -6740,7 +7123,9 @@
     heap_->SetObjectId(object, kUnallocatedReference);
     ASSERT(IsReachableReference(heap_->GetObjectId(object)));
     stack_.Add(object);
-    num_written_objects_++;
+    if (!(is_code && Code::IsDiscarded(Code::RawCast(object)))) {
+      num_written_objects_++;
+    }
 #if defined(SNAPSHOT_BACKTRACE)
     parent_pairs_.Add(&Object::Handle(zone_, object));
     parent_pairs_.Add(&Object::Handle(zone_, current_parent_));
@@ -6852,6 +7237,11 @@
 #define CID_CLUSTER(Type)                                                      \
   reinterpret_cast<Type##SerializationCluster*>(clusters_by_cid_[k##Type##Cid])
 
+const CompressedStackMaps& SerializationRoots::canonicalized_stack_map_entries()
+    const {
+  return CompressedStackMaps::Handle();
+}
+
 ZoneGrowableArray<Object*>* Serializer::Serialize(SerializationRoots* roots) {
   // While object_currently_writing_ is initialized to the artificial root, we
   // set up a scope to ensure proper flushing to the profile.
@@ -6967,7 +7357,7 @@
     cid_clusters[cid] = cluster;
   }
 
-  instructions_table_len_ = PrepareInstructions();
+  PrepareInstructions(roots->canonicalized_stack_map_entries());
 
   intptr_t num_objects = num_base_objects_ + num_written_objects_;
 #if defined(ARCH_IS_64_BIT)
@@ -6987,6 +7377,7 @@
   }
   ASSERT((instructions_table_len_ == 0) || FLAG_precompiled_mode);
   WriteUnsigned(instructions_table_len_);
+  WriteUnsigned(instructions_table_rodata_offset_);
 
   for (SerializationCluster* cluster : clusters) {
     cluster->WriteAndMeasureAlloc(this);
@@ -7030,6 +7421,7 @@
   PrintSnapshotSizes();
 
   heap()->ResetObjectIdTable();
+
   return objects_;
 }
 #endif  // !defined(DART_PRECOMPILED_RUNTIME)
@@ -7092,12 +7484,6 @@
   }
 
   ASSERT(code_cluster_ != nullptr);
-  // Reference IDs in a cluster are allocated sequentially, so we can use the
-  // first code object's reference ID to calculate the cluster index.
-  const intptr_t first_code_id = RefId(code_cluster_->objects()->At(0));
-  // The first object in the code cluster must have its reference ID allocated.
-  ASSERT(IsAllocatedReference(first_code_id));
-
   // If instructions can be deduped, the code order table in the deserializer
   // may not contain all Code objects in the snapshot. Thus, we write the ID
   // for the first code object here so we can retrieve it during deserialization
@@ -7112,8 +7498,7 @@
   // We could also map Code objects to the first Code object in the cluster with
   // the same entry point and serialize that ID instead, but that loses
   // information about which Code object was originally referenced.
-  ASSERT(first_code_id <= compiler::target::kWordMax);
-  WriteUnsigned(first_code_id);
+  WriteUnsigned(code_cluster_->first_ref());
 
   CodePtr previous_code = nullptr;
   CodePtr recent[kDispatchTableRecentCount] = {nullptr};
@@ -7154,11 +7539,9 @@
     }
     // We have a non-repeated, non-recent entry, so encode the reference ID of
     // the code object and emit that.
-    auto const object_id = RefId(code);
-    // Make sure that this code object has an allocated reference ID.
-    ASSERT(IsAllocatedReference(object_id));
+    auto const code_index = GetCodeIndex(code);
     // Use the index in the code cluster, not in the snapshot..
-    auto const encoded = kDispatchTableIndexBase + (object_id - first_code_id);
+    auto const encoded = kDispatchTableIndexBase + code_index;
     ASSERT(encoded <= compiler::target::kWordMax);
     Write(encoded);
     recent[recent_index] = code;
@@ -7225,8 +7608,7 @@
     }
     if (instructions_table_len_ > 0) {
       const intptr_t memory_size =
-          compiler::target::InstructionsTable::InstanceSize(
-              instructions_table_len_) +
+          compiler::target::InstructionsTable::InstanceSize() +
           compiler::target::Array::InstanceSize(instructions_table_len_);
       clusters_by_size.Add(new (zone_) FakeSerializationCluster(
           "InstructionsTable", instructions_table_len_, 0, memory_size));
@@ -7278,7 +7660,6 @@
       image_reader_(nullptr),
       refs_(nullptr),
       next_ref_index_(kFirstReference),
-      previous_text_offset_(0),
       clusters_(nullptr),
       initial_field_table_(thread->isolate_group()->initial_field_table()),
       is_non_root_unit_(is_non_root_unit),
@@ -7473,6 +7854,10 @@
       return new (Z) StringDeserializationCluster(
           is_canonical,
           !is_non_root_unit_ && isolate_group() != Dart::vm_isolate_group());
+#define CASE_FFI_CID(name) case kFfi##name##Cid:
+      CLASS_LIST_FFI_TYPE_MARKER(CASE_FFI_CID)
+#undef CASE_FFI_CID
+      return new (Z) InstanceDeserializationCluster(cid, is_canonical);
     default:
       break;
   }
@@ -7480,25 +7865,25 @@
   return NULL;
 }
 
-void Deserializer::ReadDispatchTable(ReadStream* stream,
-                                     bool deferred,
-                                     intptr_t deferred_code_start_index,
-                                     intptr_t deferred_code_end_index) {
+void Deserializer::ReadDispatchTable(
+    ReadStream* stream,
+    bool deferred,
+    const InstructionsTable& root_instruction_table,
+    intptr_t deferred_code_start_index,
+    intptr_t deferred_code_end_index) {
 #if defined(DART_PRECOMPILED_RUNTIME)
   const uint8_t* table_snapshot_start = stream->AddressOfCurrentPosition();
   const intptr_t length = stream->ReadUnsigned();
   if (length == 0) return;
 
-  // Not all Code objects may be in the code_order_table when instructions can
-  // be deduplicated. Thus, we serialize the reference ID of the first code
-  // object, from which we can get the reference ID for any code object.
   const intptr_t first_code_id = stream->ReadUnsigned();
+  deferred_code_start_index -= first_code_id;
+  deferred_code_end_index -= first_code_id;
 
   auto const IG = isolate_group();
   auto code = IG->object_store()->dispatch_table_null_error_stub();
   ASSERT(code != Code::null());
   uword null_entry = Code::EntryPointOf(code);
-  uword not_loaded_entry = StubCode::NotLoaded().EntryPoint();
 
   DispatchTable* table;
   if (deferred) {
@@ -7529,24 +7914,20 @@
     } else if (encoded <= kDispatchTableMaxRepeat) {
       repeat_count = encoded - 1;
     } else {
-      intptr_t cluster_index = encoded - kDispatchTableIndexBase;
+      const intptr_t code_index = encoded - kDispatchTableIndexBase;
       if (deferred) {
-        intptr_t id = first_code_id + cluster_index;
-        if ((deferred_code_start_index <= id) &&
-            (id < deferred_code_end_index)) {
-          // Deferred instructions are at the end of the instructions table.
-          value = instructions_table().EntryPointAt(
-              instructions_table().length() - deferred_code_end_index + id);
+        const intptr_t code_id =
+            CodeIndexToClusterIndex(root_instruction_table, code_index);
+        if ((deferred_code_start_index <= code_id) &&
+            (code_id < deferred_code_end_index)) {
+          auto code = static_cast<CodePtr>(Ref(first_code_id + code_id));
+          value = Code::EntryPointOf(code);
         } else {
           // Reuse old value from the dispatch table.
           value = array[i];
         }
       } else {
-        if (cluster_index < instructions_table().length()) {
-          value = instructions_table().EntryPointAt(cluster_index);
-        } else {
-          value = not_loaded_entry;
-        }
+        value = GetEntryPointByCodeIndex(code_index);
       }
       recent[recent_index] = value;
       recent_index = (recent_index + 1) & kDispatchTableRecentMask;
@@ -7682,11 +8063,8 @@
   return ApiError::New(msg, Heap::kOld);
 }
 
-void Deserializer::ReadInstructions(CodePtr code,
-                                    bool deferred,
-                                    bool discarded) {
+void Deserializer::ReadInstructions(CodePtr code, bool deferred) {
   if (deferred) {
-    ASSERT(!discarded);
 #if defined(DART_PRECOMPILED_RUNTIME)
     uword entry_point = StubCode::NotLoaded().EntryPoint();
     code->untag()->entry_point_ = entry_point;
@@ -7701,9 +8079,9 @@
   }
 
 #if defined(DART_PRECOMPILED_RUNTIME)
-  previous_text_offset_ += ReadUnsigned();
-  const uword payload_start =
-      image_reader_->GetBareInstructionsAt(previous_text_offset_);
+  const uword payload_start = instructions_table_.EntryPointAt(
+      instructions_table_.rodata()->first_entry_with_code +
+      instructions_index_);
   const uint32_t payload_info = ReadUnsigned();
   const uint32_t unchecked_offset = payload_info >> 1;
   const bool has_monomorphic_entrypoint = (payload_info & 0x1) == 0x1;
@@ -7717,23 +8095,15 @@
   const uword monomorphic_entry_point =
       payload_start + monomorphic_entry_offset;
 
-  ObjectPtr code_descriptor = code;
-  if (discarded) {
-    code_descriptor = static_cast<CompressedStackMapsPtr>(ReadRef());
-  }
+  instructions_table_.SetCodeAt(instructions_index_++, code);
 
-  instructions_table_.SetEntryAt(instructions_index_++, payload_start,
-                                 has_monomorphic_entrypoint, code_descriptor);
-
-  if (!discarded) {
-    // There are no serialized RawInstructions objects in this mode.
-    code->untag()->instructions_ = Instructions::null();
-    code->untag()->entry_point_ = entry_point;
-    code->untag()->unchecked_entry_point_ = entry_point + unchecked_offset;
-    code->untag()->monomorphic_entry_point_ = monomorphic_entry_point;
-    code->untag()->monomorphic_unchecked_entry_point_ =
-        monomorphic_entry_point + unchecked_offset;
-  }
+  // There are no serialized RawInstructions objects in this mode.
+  code->untag()->instructions_ = Instructions::null();
+  code->untag()->entry_point_ = entry_point;
+  code->untag()->unchecked_entry_point_ = entry_point + unchecked_offset;
+  code->untag()->monomorphic_entry_point_ = monomorphic_entry_point;
+  code->untag()->monomorphic_unchecked_entry_point_ =
+      monomorphic_entry_point + unchecked_offset;
 #else
   InstructionsPtr instr = image_reader_->GetInstructionsAt(Read<uint32_t>());
   uint32_t unchecked_offset = ReadUnsigned();
@@ -7751,15 +8121,21 @@
 
 void Deserializer::EndInstructions() {
 #if defined(DART_PRECOMPILED_RUNTIME)
+  if (instructions_table_.IsNull()) {
+    ASSERT(instructions_index_ == 0);
+    return;
+  }
+
+  const auto& code_objects =
+      Array::Handle(instructions_table_.ptr()->untag()->code_objects());
+  ASSERT(code_objects.Length() == instructions_index_);
+
   uword previous_end = image_reader_->GetBareInstructionsEnd();
   for (intptr_t i = instructions_index_ - 1; i >= 0; --i) {
-    ObjectPtr descriptor = instructions_table_.DescriptorAt(i);
-    uword start = instructions_table_.PayloadStartAt(i);
+    CodePtr code = Code::RawCast(code_objects.At(i));
+    uword start = Code::PayloadStartOf(code);
     ASSERT(start <= previous_end);
-    if (descriptor->IsCode()) {
-      CodePtr code = static_cast<CodePtr>(descriptor);
-      code->untag()->instructions_length_ = previous_end - start;
-    }
+    code->untag()->instructions_length_ = previous_end - start;
     previous_end = start;
   }
 
@@ -7772,6 +8148,8 @@
   }
   if ((tables.Length() == 0) ||
       (tables.At(tables.Length() - 1) != instructions_table_.ptr())) {
+    ASSERT((!is_non_root_unit_ && tables.Length() == 0) ||
+           (is_non_root_unit_ && tables.Length() > 0));
     tables.Add(instructions_table_, Heap::kOld);
   }
 #endif
@@ -7805,6 +8183,8 @@
   num_clusters_ = ReadUnsigned();
   const intptr_t initial_field_table_len = ReadUnsigned();
   const intptr_t instructions_table_len = ReadUnsigned();
+  const uint32_t instruction_table_data_offset = ReadUnsigned();
+  USE(instruction_table_data_offset);
 
   clusters_ = new DeserializationCluster*[num_clusters_];
   refs = Array::New(num_objects_ + kFirstReference, Heap::kOld);
@@ -7818,8 +8198,18 @@
     ASSERT(FLAG_precompiled_mode);
     const uword start_pc = image_reader_->GetBareInstructionsAt(0);
     const uword end_pc = image_reader_->GetBareInstructionsEnd();
-    instructions_table_ =
-        InstructionsTable::New(instructions_table_len, start_pc, end_pc);
+    uword instruction_table_data = 0;
+    if (instruction_table_data_offset != 0) {
+      // NoSafepointScope to satisfy assertion in DataStart. InstructionsTable
+      // data resides in RO memory and is immovable and immortal making it
+      // safe to use DataStart result outside of NoSafepointScope.
+      NoSafepointScope no_safepoint;
+      instruction_table_data = reinterpret_cast<uword>(
+          OneByteString::DataStart(String::Handle(static_cast<StringPtr>(
+              image_reader_->GetObjectAt(instruction_table_data_offset)))));
+    }
+    instructions_table_ = InstructionsTable::New(
+        instructions_table_len, start_pc, end_pc, instruction_table_data);
   }
 #else
   ASSERT(instructions_table_len == 0);
diff --git a/runtime/vm/app_snapshot.h b/runtime/vm/app_snapshot.h
index 7bc3032..ce084c0 100644
--- a/runtime/vm/app_snapshot.h
+++ b/runtime/vm/app_snapshot.h
@@ -176,6 +176,8 @@
   virtual void AddBaseObjects(Serializer* serializer) = 0;
   virtual void PushRoots(Serializer* serializer) = 0;
   virtual void WriteRoots(Serializer* serializer) = 0;
+
+  virtual const CompressedStackMaps& canonicalized_stack_map_entries() const;
 };
 
 class DeserializationRoots {
@@ -228,9 +230,12 @@
   void AddBaseObject(ObjectPtr base_object,
                      const char* type = nullptr,
                      const char* name = nullptr);
+
   intptr_t AssignRef(ObjectPtr object);
   intptr_t AssignArtificialRef(ObjectPtr object = nullptr);
 
+  intptr_t GetCodeIndex(CodePtr code);
+
   void Push(ObjectPtr object);
 
   void AddUntracedRef() { num_written_objects_++; }
@@ -418,8 +423,8 @@
   }
 
   // Sorts Code objects and reorders instructions before writing snapshot.
-  // Returns length of instructions table (in bare instructions mode).
-  intptr_t PrepareInstructions();
+  // Builds binary search table for stack maps.
+  void PrepareInstructions(const CompressedStackMaps& canonical_smap);
 
   void WriteInstructions(InstructionsPtr instr,
                          uint32_t unchecked_offset,
@@ -508,12 +513,12 @@
   intptr_t num_base_objects_;
   intptr_t num_written_objects_;
   intptr_t next_ref_index_;
-  intptr_t previous_text_offset_;
   FieldTable* initial_field_table_;
 
   intptr_t dispatch_table_size_ = 0;
   intptr_t bytes_heap_allocated_ = 0;
   intptr_t instructions_table_len_ = 0;
+  intptr_t instructions_table_rodata_offset_ = 0;
 
   // True if writing VM snapshot, false for Isolate snapshot.
   bool vm_;
@@ -537,6 +542,7 @@
 
 #if defined(DART_PRECOMPILER)
   IntMap<intptr_t> deduped_instructions_sources_;
+  IntMap<intptr_t> code_index_;
 #endif
 
   intptr_t current_loading_unit_id_ = 0;
@@ -657,6 +663,16 @@
     return refs_->untag()->element(index);
   }
 
+  CodePtr GetCodeByIndex(intptr_t code_index, uword* entry_point) const;
+  uword GetEntryPointByCodeIndex(intptr_t code_index) const;
+
+  // If |code_index| corresponds to a non-discarded Code object returns
+  // index within the code cluster that corresponds to this Code object.
+  // Otherwise, if |code_index| corresponds to the discarded Code then
+  // returns -1.
+  static intptr_t CodeIndexToClusterIndex(const InstructionsTable& table,
+                                          intptr_t code_index);
+
   ObjectPtr ReadRef() { return Ref(ReadUnsigned()); }
 
   template <typename T, typename... P>
@@ -685,7 +701,7 @@
     return Read<int32_t>();
   }
 
-  void ReadInstructions(CodePtr code, bool deferred, bool discarded);
+  void ReadInstructions(CodePtr code, bool deferred);
   void EndInstructions();
   ObjectPtr GetObjectAt(uint32_t offset) const;
 
@@ -694,10 +710,12 @@
   DeserializationCluster* ReadCluster();
 
   void ReadDispatchTable() {
-    ReadDispatchTable(&stream_, /*deferred=*/false, -1, -1);
+    ReadDispatchTable(&stream_, /*deferred=*/false, InstructionsTable::Handle(),
+                      -1, -1);
   }
   void ReadDispatchTable(ReadStream* stream,
                          bool deferred,
+                         const InstructionsTable& root_instruction_table,
                          intptr_t deferred_code_start_index,
                          intptr_t deferred_code_end_index);
 
@@ -708,10 +726,13 @@
   FieldTable* initial_field_table() const { return initial_field_table_; }
   bool is_non_root_unit() const { return is_non_root_unit_; }
   void set_code_start_index(intptr_t value) { code_start_index_ = value; }
-  intptr_t code_start_index() { return code_start_index_; }
+  intptr_t code_start_index() const { return code_start_index_; }
+  void set_code_stop_index(intptr_t value) { code_stop_index_ = value; }
+  intptr_t code_stop_index() const { return code_stop_index_; }
   const InstructionsTable& instructions_table() const {
     return instructions_table_;
   }
+  intptr_t num_base_objects() const { return num_base_objects_; }
 
  private:
   Heap* heap_;
@@ -724,8 +745,8 @@
   intptr_t num_clusters_;
   ArrayPtr refs_;
   intptr_t next_ref_index_;
-  intptr_t previous_text_offset_;
   intptr_t code_start_index_ = 0;
+  intptr_t code_stop_index_ = 0;
   intptr_t instructions_index_ = 0;
   DeserializationCluster** clusters_;
   FieldTable* initial_field_table_;
diff --git a/runtime/vm/bitmap_test.cc b/runtime/vm/bitmap_test.cc
index 2fdab17..0e7837f 100644
--- a/runtime/vm/bitmap_test.cc
+++ b/runtime/vm/bitmap_test.cc
@@ -53,7 +53,7 @@
   // Create a CompressedStackMaps object and verify its contents.
   const auto& maps1 = CompressedStackMaps::Handle(
       thread->zone(), MapsFromBuilder(thread->zone(), builder1));
-  CompressedStackMaps::Iterator it1(thread, maps1);
+  auto it1 = maps1.iterator(thread);
   EXPECT(it1.MoveNext());
 
   EXPECT_EQ(kTestPcOffset, it1.pc_offset());
@@ -86,7 +86,7 @@
 
   const auto& maps2 = CompressedStackMaps::Handle(
       thread->zone(), MapsFromBuilder(thread->zone(), builder1));
-  CompressedStackMaps::Iterator it2(thread, maps2);
+  auto it2 = maps2.iterator(thread);
   EXPECT(it2.MoveNext());
 
   EXPECT_EQ(kTestPcOffset, it2.pc_offset());
diff --git a/runtime/vm/bootstrap_natives.h b/runtime/vm/bootstrap_natives.h
index adade03..ca3d03c 100644
--- a/runtime/vm/bootstrap_natives.h
+++ b/runtime/vm/bootstrap_natives.h
@@ -18,7 +18,6 @@
   V(DartAsync_fatal, 1)                                                        \
   V(Object_equals, 2)                                                          \
   V(Object_getHash, 1)                                                         \
-  V(Object_setHashIfNotSetYet, 2)                                              \
   V(Object_toString, 1)                                                        \
   V(Object_runtimeType, 1)                                                     \
   V(Object_haveSameRuntimeType, 2)                                             \
@@ -366,6 +365,8 @@
   V(VMService_CancelStream, 1)                                                 \
   V(VMService_RequestAssets, 0)                                                \
   V(VMService_DecodeAssets, 1)                                                 \
+  V(VMService_AddUserTagsToStreamableSampleList, 1)                            \
+  V(VMService_RemoveUserTagsFromStreamableSampleList, 1)                       \
   V(Ffi_loadInt8, 2)                                                           \
   V(Ffi_loadInt16, 2)                                                          \
   V(Ffi_loadInt32, 2)                                                          \
diff --git a/runtime/vm/class_table.cc b/runtime/vm/class_table.cc
index a1c58c0..edec756 100644
--- a/runtime/vm/class_table.cc
+++ b/runtime/vm/class_table.cc
@@ -534,6 +534,70 @@
   shared_class_table_->SetSizeAt(cid, size);
 }
 
+#if defined(DART_PRECOMPILER)
+void ClassTable::PrintObjectLayout(const char* filename) {
+  Class& cls = Class::Handle();
+  Array& fields = Array::Handle();
+  Field& field = Field::Handle();
+
+  JSONWriter js;
+  js.OpenArray();
+  for (intptr_t i = ClassId::kObjectCid; i < top_; i++) {
+    if (!HasValidClassAt(i)) {
+      continue;
+    }
+    cls = At(i);
+    ASSERT(!cls.IsNull());
+    ASSERT(cls.id() != kIllegalCid);
+    ASSERT(cls.is_finalized());  // Precompiler already finalized all classes.
+    ASSERT(!cls.IsTopLevel());
+    js.OpenObject();
+    js.PrintProperty("class", cls.UserVisibleNameCString());
+    js.PrintProperty("size", cls.target_instance_size());
+    js.OpenArray("fields");
+    fields = cls.fields();
+    if (!fields.IsNull()) {
+      for (intptr_t i = 0, n = fields.Length(); i < n; ++i) {
+        field ^= fields.At(i);
+        js.OpenObject();
+        js.PrintProperty("field", field.UserVisibleNameCString());
+        if (field.is_static()) {
+          js.PrintPropertyBool("static", true);
+        } else {
+          js.PrintProperty("offset", field.TargetOffset());
+        }
+        js.CloseObject();
+      }
+    }
+    js.CloseArray();
+    js.CloseObject();
+  }
+  js.CloseArray();
+
+  auto file_open = Dart::file_open_callback();
+  auto file_write = Dart::file_write_callback();
+  auto file_close = Dart::file_close_callback();
+  if ((file_open == nullptr) || (file_write == nullptr) ||
+      (file_close == nullptr)) {
+    OS::PrintErr("warning: Could not access file callbacks.");
+    return;
+  }
+
+  void* file = file_open(filename, /*write=*/true);
+  if (file == nullptr) {
+    OS::PrintErr("warning: Failed to write object layout: %s\n", filename);
+    return;
+  }
+
+  char* output = nullptr;
+  intptr_t output_length = 0;
+  js.Steal(&output, &output_length);
+  file_write(output, output_length, file);
+  free(output);
+  file_close(file);
+}
+#endif  // defined(DART_PRECOMPILER)
+
 #ifndef PRODUCT
 void ClassTable::PrintToJSONObject(JSONObject* object) {
   Class& cls = Class::Handle();
diff --git a/runtime/vm/class_table.h b/runtime/vm/class_table.h
index e89b978..1e6ca5f 100644
--- a/runtime/vm/class_table.h
+++ b/runtime/vm/class_table.h
@@ -394,6 +394,10 @@
 
   void Print();
 
+#if defined(DART_PRECOMPILER)
+  void PrintObjectLayout(const char* filename);
+#endif
+
 #ifndef PRODUCT
   // Describes layout of heap stats for code generation. See offset_extractor.cc
   struct ArrayTraits {
diff --git a/runtime/vm/compiler/aot/aot_call_specializer.cc b/runtime/vm/compiler/aot/aot_call_specializer.cc
index a013cb2..a8e2f04 100644
--- a/runtime/vm/compiler/aot/aot_call_specializer.cc
+++ b/runtime/vm/compiler/aot/aot_call_specializer.cc
@@ -646,10 +646,6 @@
       case Token::kMUL:
         FALL_THROUGH;
       case Token::kDIV: {
-        if (op_kind == Token::kDIV &&
-            !FlowGraphCompiler::SupportsHardwareDivision()) {
-          return false;
-        }
         left_value = PrepareStaticOpInput(left_value, kDoubleCid, instr);
         right_value = PrepareStaticOpInput(right_value, kDoubleCid, instr);
         replacement = new (Z) BinaryDoubleOpInstr(
diff --git a/runtime/vm/compiler/aot/precompiler.cc b/runtime/vm/compiler/aot/precompiler.cc
index 3726ba2..930e8ad 100644
--- a/runtime/vm/compiler/aot/precompiler.cc
+++ b/runtime/vm/compiler/aot/precompiler.cc
@@ -67,6 +67,10 @@
             "Print per-phase breakdown of time spent precompiling");
 DEFINE_FLAG(bool, print_unique_targets, false, "Print unique dynamic targets");
 DEFINE_FLAG(bool, print_gop, false, "Print global object pool");
+DEFINE_FLAG(charp,
+            print_object_layout_to,
+            nullptr,
+            "Print layout of Dart objects to the given file");
 DEFINE_FLAG(bool, trace_precompiler, false, "Trace precompiler.");
 DEFINE_FLAG(
     int,
@@ -469,6 +473,10 @@
       FinalizeAllClasses();
       ASSERT(Error::Handle(Z, T->sticky_error()).IsNull());
 
+      if (FLAG_print_object_layout_to != nullptr) {
+        IG->class_table()->PrintObjectLayout(FLAG_print_object_layout_to);
+      }
+
       ClassFinalizer::SortClasses();
 
       // Collects type usage information which allows us to decide when/how to
diff --git a/runtime/vm/compiler/asm_intrinsifier_arm.cc b/runtime/vm/compiler/asm_intrinsifier_arm.cc
index b61046d..3b8931c 100644
--- a/runtime/vm/compiler/asm_intrinsifier_arm.cc
+++ b/runtime/vm/compiler/asm_intrinsifier_arm.cc
@@ -765,32 +765,30 @@
 static void CompareDoubles(Assembler* assembler,
                            Label* normal_ir_body,
                            Condition true_condition) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    Label is_smi, double_op;
+  Label is_smi, double_op;
 
-    TestLastArgumentIsDouble(assembler, &is_smi, normal_ir_body);
-    // Both arguments are double, right operand is in R0.
+  TestLastArgumentIsDouble(assembler, &is_smi, normal_ir_body);
+  // Both arguments are double, right operand is in R0.
 
-    __ LoadDFromOffset(D1, R0, target::Double::value_offset() - kHeapObjectTag);
-    __ Bind(&double_op);
-    __ ldr(R0, Address(SP, 1 * target::kWordSize));  // Left argument.
-    __ LoadDFromOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
+  __ LoadDFromOffset(D1, R0, target::Double::value_offset() - kHeapObjectTag);
+  __ Bind(&double_op);
+  __ ldr(R0, Address(SP, 1 * target::kWordSize));  // Left argument.
+  __ LoadDFromOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
 
-    __ vcmpd(D0, D1);
-    __ vmstat();
-    __ LoadObject(R0, CastHandle<Object>(FalseObject()));
-    // Return false if D0 or D1 was NaN before checking true condition.
-    READS_RETURN_ADDRESS_FROM_LR(__ bx(LR, VS));
-    __ LoadObject(R0, CastHandle<Object>(TrueObject()), true_condition);
-    __ Ret();
+  __ vcmpd(D0, D1);
+  __ vmstat();
+  __ LoadObject(R0, CastHandle<Object>(FalseObject()));
+  // Return false if D0 or D1 was NaN before checking true condition.
+  READS_RETURN_ADDRESS_FROM_LR(__ bx(LR, VS));
+  __ LoadObject(R0, CastHandle<Object>(TrueObject()), true_condition);
+  __ Ret();
 
-    __ Bind(&is_smi);  // Convert R0 to a double.
-    __ SmiUntag(R0);
-    __ vmovsr(S0, R0);
-    __ vcvtdi(D1, S0);
-    __ b(&double_op);  // Then do the comparison.
-    __ Bind(normal_ir_body);
-  }
+  __ Bind(&is_smi);  // Convert R0 to a double.
+  __ SmiUntag(R0);
+  __ vmovsr(S0, R0);
+  __ vcvtdi(D1, S0);
+  __ b(&double_op);  // Then do the comparison.
+  __ Bind(normal_ir_body);
 }
 
 void AsmIntrinsifier::Double_greaterThan(Assembler* assembler,
@@ -823,43 +821,41 @@
 static void DoubleArithmeticOperations(Assembler* assembler,
                                        Label* normal_ir_body,
                                        Token::Kind kind) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    Label is_smi, double_op;
+  Label is_smi, double_op;
 
-    TestLastArgumentIsDouble(assembler, &is_smi, normal_ir_body);
-    // Both arguments are double, right operand is in R0.
-    __ LoadDFromOffset(D1, R0, target::Double::value_offset() - kHeapObjectTag);
-    __ Bind(&double_op);
-    __ ldr(R0, Address(SP, 1 * target::kWordSize));  // Left argument.
-    __ LoadDFromOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
-    switch (kind) {
-      case Token::kADD:
-        __ vaddd(D0, D0, D1);
-        break;
-      case Token::kSUB:
-        __ vsubd(D0, D0, D1);
-        break;
-      case Token::kMUL:
-        __ vmuld(D0, D0, D1);
-        break;
-      case Token::kDIV:
-        __ vdivd(D0, D0, D1);
-        break;
-      default:
-        UNREACHABLE();
-    }
-    const Class& double_class = DoubleClass();
-    __ TryAllocate(double_class, normal_ir_body, Assembler::kFarJump, R0,
-                   R1);  // Result register.
-    __ StoreDToOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
-    __ Ret();
-    __ Bind(&is_smi);  // Convert R0 to a double.
-    __ SmiUntag(R0);
-    __ vmovsr(S0, R0);
-    __ vcvtdi(D1, S0);
-    __ b(&double_op);
-    __ Bind(normal_ir_body);
+  TestLastArgumentIsDouble(assembler, &is_smi, normal_ir_body);
+  // Both arguments are double, right operand is in R0.
+  __ LoadDFromOffset(D1, R0, target::Double::value_offset() - kHeapObjectTag);
+  __ Bind(&double_op);
+  __ ldr(R0, Address(SP, 1 * target::kWordSize));  // Left argument.
+  __ LoadDFromOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
+  switch (kind) {
+    case Token::kADD:
+      __ vaddd(D0, D0, D1);
+      break;
+    case Token::kSUB:
+      __ vsubd(D0, D0, D1);
+      break;
+    case Token::kMUL:
+      __ vmuld(D0, D0, D1);
+      break;
+    case Token::kDIV:
+      __ vdivd(D0, D0, D1);
+      break;
+    default:
+      UNREACHABLE();
   }
+  const Class& double_class = DoubleClass();
+  __ TryAllocate(double_class, normal_ir_body, Assembler::kFarJump, R0,
+                 R1);  // Result register.
+  __ StoreDToOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
+  __ Ret();
+  __ Bind(&is_smi);  // Convert R0 to a double.
+  __ SmiUntag(R0);
+  __ vmovsr(S0, R0);
+  __ vcvtdi(D1, S0);
+  __ b(&double_op);
+  __ Bind(normal_ir_body);
 }
 
 void AsmIntrinsifier::Double_add(Assembler* assembler, Label* normal_ir_body) {
@@ -881,123 +877,111 @@
 // Left is double, right is integer (Mint or Smi)
 void AsmIntrinsifier::Double_mulFromInteger(Assembler* assembler,
                                             Label* normal_ir_body) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    Label fall_through;
-    // Only smis allowed.
-    __ ldr(R0, Address(SP, 0 * target::kWordSize));
-    __ tst(R0, Operand(kSmiTagMask));
-    __ b(normal_ir_body, NE);
-    // Is Smi.
-    __ SmiUntag(R0);
-    __ vmovsr(S0, R0);
-    __ vcvtdi(D1, S0);
-    __ ldr(R0, Address(SP, 1 * target::kWordSize));
-    __ LoadDFromOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
-    __ vmuld(D0, D0, D1);
-    const Class& double_class = DoubleClass();
-    __ TryAllocate(double_class, normal_ir_body, Assembler::kFarJump, R0,
-                   R1);  // Result register.
-    __ StoreDToOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
-    __ Ret();
-    __ Bind(normal_ir_body);
-  }
+  Label fall_through;
+  // Only smis allowed.
+  __ ldr(R0, Address(SP, 0 * target::kWordSize));
+  __ tst(R0, Operand(kSmiTagMask));
+  __ b(normal_ir_body, NE);
+  // Is Smi.
+  __ SmiUntag(R0);
+  __ vmovsr(S0, R0);
+  __ vcvtdi(D1, S0);
+  __ ldr(R0, Address(SP, 1 * target::kWordSize));
+  __ LoadDFromOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
+  __ vmuld(D0, D0, D1);
+  const Class& double_class = DoubleClass();
+  __ TryAllocate(double_class, normal_ir_body, Assembler::kFarJump, R0,
+                 R1);  // Result register.
+  __ StoreDToOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
+  __ Ret();
+  __ Bind(normal_ir_body);
 }
 
 void AsmIntrinsifier::DoubleFromInteger(Assembler* assembler,
                                         Label* normal_ir_body) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    Label fall_through;
+  Label fall_through;
 
-    __ ldr(R0, Address(SP, 0 * target::kWordSize));
-    __ tst(R0, Operand(kSmiTagMask));
-    __ b(normal_ir_body, NE);
-    // Is Smi.
-    __ SmiUntag(R0);
-    __ vmovsr(S0, R0);
-    __ vcvtdi(D0, S0);
-    const Class& double_class = DoubleClass();
-    __ TryAllocate(double_class, normal_ir_body, Assembler::kFarJump, R0,
-                   R1);  // Result register.
-    __ StoreDToOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
-    __ Ret();
-    __ Bind(normal_ir_body);
-  }
+  __ ldr(R0, Address(SP, 0 * target::kWordSize));
+  __ tst(R0, Operand(kSmiTagMask));
+  __ b(normal_ir_body, NE);
+  // Is Smi.
+  __ SmiUntag(R0);
+  __ vmovsr(S0, R0);
+  __ vcvtdi(D0, S0);
+  const Class& double_class = DoubleClass();
+  __ TryAllocate(double_class, normal_ir_body, Assembler::kFarJump, R0,
+                 R1);  // Result register.
+  __ StoreDToOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
+  __ Ret();
+  __ Bind(normal_ir_body);
 }
 
 void AsmIntrinsifier::Double_getIsNaN(Assembler* assembler,
                                       Label* normal_ir_body) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ ldr(R0, Address(SP, 0 * target::kWordSize));
-    __ LoadDFromOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
-    __ vcmpd(D0, D0);
-    __ vmstat();
-    __ LoadObject(R0, CastHandle<Object>(FalseObject()), VC);
-    __ LoadObject(R0, CastHandle<Object>(TrueObject()), VS);
-    __ Ret();
-  }
+  __ ldr(R0, Address(SP, 0 * target::kWordSize));
+  __ LoadDFromOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
+  __ vcmpd(D0, D0);
+  __ vmstat();
+  __ LoadObject(R0, CastHandle<Object>(FalseObject()), VC);
+  __ LoadObject(R0, CastHandle<Object>(TrueObject()), VS);
+  __ Ret();
 }
 
 void AsmIntrinsifier::Double_getIsInfinite(Assembler* assembler,
                                            Label* normal_ir_body) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ ldr(R0, Address(SP, 0 * target::kWordSize));
-    // R1 <- value[0:31], R2 <- value[32:63]
-    __ LoadFieldFromOffset(R1, R0, target::Double::value_offset());
-    __ LoadFieldFromOffset(R2, R0,
-                           target::Double::value_offset() + target::kWordSize);
+  __ ldr(R0, Address(SP, 0 * target::kWordSize));
+  // R1 <- value[0:31], R2 <- value[32:63]
+  __ LoadFieldFromOffset(R1, R0, target::Double::value_offset());
+  __ LoadFieldFromOffset(R2, R0,
+                         target::Double::value_offset() + target::kWordSize);
 
-    // If the low word isn't 0, then it isn't infinity.
-    __ cmp(R1, Operand(0));
-    __ LoadObject(R0, CastHandle<Object>(FalseObject()), NE);
-    READS_RETURN_ADDRESS_FROM_LR(__ bx(LR, NE));  // Return if NE.
+  // If the low word isn't 0, then it isn't infinity.
+  __ cmp(R1, Operand(0));
+  __ LoadObject(R0, CastHandle<Object>(FalseObject()), NE);
+  READS_RETURN_ADDRESS_FROM_LR(__ bx(LR, NE));  // Return if NE.
 
-    // Mask off the sign bit.
-    __ AndImmediate(R2, R2, 0x7FFFFFFF);
-    // Compare with +infinity.
-    __ CompareImmediate(R2, 0x7FF00000);
-    __ LoadObject(R0, CastHandle<Object>(FalseObject()), NE);
-    READS_RETURN_ADDRESS_FROM_LR(__ bx(LR, NE));
-    __ LoadObject(R0, CastHandle<Object>(TrueObject()));
-    __ Ret();
-  }
+  // Mask off the sign bit.
+  __ AndImmediate(R2, R2, 0x7FFFFFFF);
+  // Compare with +infinity.
+  __ CompareImmediate(R2, 0x7FF00000);
+  __ LoadObject(R0, CastHandle<Object>(FalseObject()), NE);
+  READS_RETURN_ADDRESS_FROM_LR(__ bx(LR, NE));
+  __ LoadObject(R0, CastHandle<Object>(TrueObject()));
+  __ Ret();
 }
 
 void AsmIntrinsifier::Double_getIsNegative(Assembler* assembler,
                                            Label* normal_ir_body) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    Label is_false, is_true, is_zero;
-    __ ldr(R0, Address(SP, 0 * target::kWordSize));
-    __ LoadDFromOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
-    __ vcmpdz(D0);
-    __ vmstat();
-    __ b(&is_false, VS);  // NaN -> false.
-    __ b(&is_zero, EQ);   // Check for negative zero.
-    __ b(&is_false, CS);  // >= 0 -> false.
+  Label is_false, is_true, is_zero;
+  __ ldr(R0, Address(SP, 0 * target::kWordSize));
+  __ LoadDFromOffset(D0, R0, target::Double::value_offset() - kHeapObjectTag);
+  __ vcmpdz(D0);
+  __ vmstat();
+  __ b(&is_false, VS);  // NaN -> false.
+  __ b(&is_zero, EQ);   // Check for negative zero.
+  __ b(&is_false, CS);  // >= 0 -> false.
 
-    __ Bind(&is_true);
-    __ LoadObject(R0, CastHandle<Object>(TrueObject()));
-    __ Ret();
+  __ Bind(&is_true);
+  __ LoadObject(R0, CastHandle<Object>(TrueObject()));
+  __ Ret();
 
-    __ Bind(&is_false);
-    __ LoadObject(R0, CastHandle<Object>(FalseObject()));
-    __ Ret();
+  __ Bind(&is_false);
+  __ LoadObject(R0, CastHandle<Object>(FalseObject()));
+  __ Ret();
 
-    __ Bind(&is_zero);
-    // Check for negative zero by looking at the sign bit.
-    __ vmovrrd(R0, R1, D0);  // R1:R0 <- D0, so sign bit is in bit 31 of R1.
-    __ mov(R1, Operand(R1, LSR, 31));
-    __ tst(R1, Operand(1));
-    __ b(&is_true, NE);  // Sign bit set.
-    __ b(&is_false);
-  }
+  __ Bind(&is_zero);
+  // Check for negative zero by looking at the sign bit.
+  __ vmovrrd(R0, R1, D0);  // R1:R0 <- D0, so sign bit is in bit 31 of R1.
+  __ mov(R1, Operand(R1, LSR, 31));
+  __ tst(R1, Operand(1));
+  __ b(&is_true, NE);  // Sign bit set.
+  __ b(&is_false);
 }
 
 void AsmIntrinsifier::Double_hashCode(Assembler* assembler,
                                       Label* normal_ir_body) {
   // TODO(dartbug.com/31174): Convert this to a graph intrinsic.
 
-  if (!TargetCPUFeatures::vfp_supported()) return;
-
   // Load double value and check that it isn't NaN, since ARM gives an
   // FPU exception if you try to convert NaN to an int.
   Label double_hash;
@@ -1548,11 +1532,6 @@
   UNREACHABLE();
 }
 
-void AsmIntrinsifier::Object_setHashIfNotSetYet(Assembler* assembler,
-                                                Label* normal_ir_body) {
-  UNREACHABLE();
-}
-
 void AsmIntrinsifier::StringBaseCharAt(Assembler* assembler,
                                        Label* normal_ir_body) {
   Label try_two_byte_string;
diff --git a/runtime/vm/compiler/asm_intrinsifier_arm64.cc b/runtime/vm/compiler/asm_intrinsifier_arm64.cc
index b6796b5..f9c178a 100644
--- a/runtime/vm/compiler/asm_intrinsifier_arm64.cc
+++ b/runtime/vm/compiler/asm_intrinsifier_arm64.cc
@@ -1578,21 +1578,37 @@
   __ Bind(normal_ir_body);
 }
 
+// Keep in sync with Instance::IdentityHashCode.
+// Note int and double never reach here because they override _identityHashCode.
+// Special cases are also not needed for null or bool because they were pre-set
+// during VM isolate finalization.
 void AsmIntrinsifier::Object_getHash(Assembler* assembler,
                                      Label* normal_ir_body) {
-  __ ldr(R0, Address(SP, 0 * target::kWordSize));
-  __ ldr(R0, FieldAddress(R0, target::String::hash_offset(), kFourBytes),
+  Label not_yet_computed;
+  __ ldr(R0, Address(SP, 0 * target::kWordSize));  // Object.
+  __ ldr(R0,
+         FieldAddress(R0,
+                      target::Object::tags_offset() +
+                          target::UntaggedObject::kHashTagPos / kBitsPerByte,
+                      kFourBytes),
          kUnsignedFourBytes);
+  __ cbz(&not_yet_computed, R0);
   __ SmiTag(R0);
   __ ret();
-}
 
-void AsmIntrinsifier::Object_setHashIfNotSetYet(Assembler* assembler,
-                                                Label* normal_ir_body) {
-  __ ldp(/*Value=*/R1, /*Object=*/R0, Address(SP, 0, Address::PairOffset));
-  // R0: Untagged address of header word (ldxr/stxr do not support offsets).
+  __ Bind(&not_yet_computed);
+  __ LoadFromOffset(R1, THR, target::Thread::random_offset());
+  __ AndImmediate(R2, R1, 0xffffffff);  // state_lo
+  __ LsrImmediate(R3, R1, 32);          // state_hi
+  __ LoadImmediate(R1, 0xffffda61);     // A
+  __ mul(R1, R1, R2);
+  __ add(R1, R1, Operand(R3));  // new_state = (A * state_lo) + state_hi
+  __ StoreToOffset(R1, THR, target::Thread::random_offset());
+  __ AndImmediate(R1, R1, 0x3fffffff);
+  __ cbz(&not_yet_computed, R1);
+
+  __ ldr(R0, Address(SP, 0 * target::kWordSize));  // Object.
   __ sub(R0, R0, Operand(kHeapObjectTag));
-  __ SmiUntag(R1);
   __ LslImmediate(R3, R1, target::UntaggedObject::kHashTagPos);
 
   Label retry, already_set_in_r4;
diff --git a/runtime/vm/compiler/asm_intrinsifier_ia32.cc b/runtime/vm/compiler/asm_intrinsifier_ia32.cc
index 0c58ca7..341c285 100644
--- a/runtime/vm/compiler/asm_intrinsifier_ia32.cc
+++ b/runtime/vm/compiler/asm_intrinsifier_ia32.cc
@@ -1555,11 +1555,6 @@
   UNREACHABLE();
 }
 
-void AsmIntrinsifier::Object_setHashIfNotSetYet(Assembler* assembler,
-                                                Label* normal_ir_body) {
-  UNREACHABLE();
-}
-
 void AsmIntrinsifier::StringBaseCharAt(Assembler* assembler,
                                        Label* normal_ir_body) {
   Label try_two_byte_string;
diff --git a/runtime/vm/compiler/asm_intrinsifier_test.cc b/runtime/vm/compiler/asm_intrinsifier_test.cc
index e5678ee..fb112f1 100644
--- a/runtime/vm/compiler/asm_intrinsifier_test.cc
+++ b/runtime/vm/compiler/asm_intrinsifier_test.cc
@@ -10,78 +10,4 @@
 
 namespace dart {
 
-static intptr_t GetHash(Isolate* isolate, const ObjectPtr obj) {
-#if defined(HASH_IN_OBJECT_HEADER)
-  return Object::GetCachedHash(obj);
-#else
-  Heap* heap = isolate->group()->heap();
-  ASSERT(obj->IsDartInstance());
-  return heap->GetHash(obj);
-#endif
-}
-
-ISOLATE_UNIT_TEST_CASE(AsmIntrinsifier_SetHashIfNotSetYet) {
-  auto I = Isolate::Current();
-  const auto& corelib = Library::Handle(Library::CoreLibrary());
-  const auto& name = String::Handle(String::New("_setHashIfNotSetYet"));
-  const auto& symbol = String::Handle(Symbols::New(thread, name));
-
-  const auto& function =
-      Function::Handle(corelib.LookupFunctionAllowPrivate(symbol));
-  const auto& object_class =
-      Class::Handle(corelib.LookupClass(Symbols::Object()));
-
-  auto& smi0 = Smi::Handle(Smi::New(0));
-  auto& smi21 = Smi::Handle(Smi::New(21));
-  auto& smi42 = Smi::Handle(Smi::New(42));
-  const auto& obj = Object::Handle(Instance::New(object_class));
-  const auto& args = Array::Handle(Array::New(2));
-
-  const auto& args_descriptor_array =
-      Array::Handle(ArgumentsDescriptor::NewBoxed(0, 2, Array::empty_array()));
-
-  // Initialized to 0
-  EXPECT_EQ(smi0.ptr(), Smi::New(GetHash(I, obj.ptr())));
-
-  // Lazily set to 42 on first call.
-  args.SetAt(0, obj);
-  args.SetAt(1, smi42);
-  EXPECT_EQ(smi42.ptr(),
-            DartEntry::InvokeFunction(function, args, args_descriptor_array));
-  EXPECT_EQ(smi42.ptr(), Smi::New(GetHash(I, obj.ptr())));
-
-  // Stays at 42 on subsequent calls.
-  args.SetAt(0, obj);
-  args.SetAt(1, smi21);
-  EXPECT_EQ(smi42.ptr(),
-            DartEntry::InvokeFunction(function, args, args_descriptor_array));
-  EXPECT_EQ(smi42.ptr(), Smi::New(GetHash(I, obj.ptr())));
-
-  // We test setting the maximum value our core libraries would use when
-  // installing an identity hash code (see
-  // sdk/lib/_internal/vm/lib/object_patch.dart:Object._objectHashCode)
-  //
-  // This value is representable as a positive Smi on all architectures (even
-  // compressed pointers).
-  const auto& smiMax = Smi::Handle(Smi::New(0x40000000 - 1));
-  const auto& obj2 = Object::Handle(Instance::New(object_class));
-
-  // Initialized to 0
-  EXPECT_EQ(smi0.ptr(), Smi::New(GetHash(I, obj2.ptr())));
-
-  // Lazily set to smiMax first call.
-  args.SetAt(0, obj2);
-  args.SetAt(1, smiMax);
-  EXPECT_EQ(smiMax.ptr(),
-            DartEntry::InvokeFunction(function, args, args_descriptor_array));
-  EXPECT_EQ(smiMax.ptr(), Smi::New(GetHash(I, obj2.ptr())));
-
-  // Stays at smiMax on subsequent calls.
-  args.SetAt(0, obj2);
-  args.SetAt(1, smi21);
-  EXPECT_EQ(smiMax.ptr(),
-            DartEntry::InvokeFunction(function, args, args_descriptor_array));
-  EXPECT_EQ(smiMax.ptr(), Smi::New(GetHash(I, obj2.ptr())));
-}
-
 }  // namespace dart
diff --git a/runtime/vm/compiler/asm_intrinsifier_x64.cc b/runtime/vm/compiler/asm_intrinsifier_x64.cc
index c4e02a9..e2f7b24 100644
--- a/runtime/vm/compiler/asm_intrinsifier_x64.cc
+++ b/runtime/vm/compiler/asm_intrinsifier_x64.cc
@@ -1452,21 +1452,35 @@
   __ Bind(normal_ir_body);
 }
 
+// Keep in sync with Instance::IdentityHashCode.
+// Note int and double never reach here because they override _identityHashCode.
+// Special cases are also not needed for null or bool because they were pre-set
+// during VM isolate finalization.
 void AsmIntrinsifier::Object_getHash(Assembler* assembler,
                                      Label* normal_ir_body) {
+  Label not_yet_computed;
   __ movq(RAX, Address(RSP, +1 * target::kWordSize));  // Object.
-  __ movl(RAX, FieldAddress(RAX, target::String::hash_offset()));
+  __ movl(RAX, FieldAddress(RAX, target::Object::tags_offset() +
+                                     target::UntaggedObject::kHashTagPos /
+                                         kBitsPerByte));
+  __ cmpl(RAX, Immediate(0));
+  __ j(EQUAL, &not_yet_computed, Assembler::kNearJump);
   __ SmiTag(RAX);
   __ ret();
-}
 
-void AsmIntrinsifier::Object_setHashIfNotSetYet(Assembler* assembler,
-                                                Label* normal_ir_body) {
-  ASSERT(target::String::hash_offset() == 4);
+  __ Bind(&not_yet_computed);
+  __ movq(RCX, Address(THR, target::Thread::random_offset()));
+  __ movq(RBX, RCX);
+  __ andq(RCX, Immediate(0xffffffff));   // state_lo
+  __ shrq(RBX, Immediate(32));           // state_hi
+  __ imulq(RCX, Immediate(0xffffda61));  // A
+  __ addq(RCX, RBX);                     // new_state = (A* state_lo) + state_hi
+  __ movq(Address(THR, target::Thread::random_offset()), RCX);
+  __ andq(RCX, Immediate(0x3fffffff));
+  __ cmpl(RCX, Immediate(0));
+  __ j(EQUAL, &not_yet_computed);
 
-  __ movq(RBX, Address(RSP, +2 * target::kWordSize));  // Object.
-  __ movq(RCX, Address(RSP, +1 * target::kWordSize));  // Value.
-  __ SmiUntag(RCX);
+  __ movq(RBX, Address(RSP, +1 * target::kWordSize));  // Object.
   __ MoveRegister(RDX, RCX);
   __ shlq(RDX, Immediate(32));
 
diff --git a/runtime/vm/compiler/assembler/assembler_arm.cc b/runtime/vm/compiler/assembler/assembler_arm.cc
index eee0fb3..a9a71ee 100644
--- a/runtime/vm/compiler/assembler/assembler_arm.cc
+++ b/runtime/vm/compiler/assembler/assembler_arm.cc
@@ -702,7 +702,6 @@
 }
 
 void Assembler::vmovsr(SRegister sn, Register rt, Condition cond) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(sn != kNoSRegister);
   ASSERT(rt != kNoRegister);
   ASSERT(rt != SP);
@@ -716,7 +715,6 @@
 }
 
 void Assembler::vmovrs(Register rt, SRegister sn, Condition cond) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(sn != kNoSRegister);
   ASSERT(rt != kNoRegister);
   ASSERT(rt != SP);
@@ -733,7 +731,6 @@
                         Register rt,
                         Register rt2,
                         Condition cond) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(sm != kNoSRegister);
   ASSERT(sm != S31);
   ASSERT(rt != kNoRegister);
@@ -755,7 +752,6 @@
                         Register rt2,
                         SRegister sm,
                         Condition cond) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(sm != kNoSRegister);
   ASSERT(sm != S31);
   ASSERT(rt != kNoRegister);
@@ -775,7 +771,6 @@
 }
 
 void Assembler::vmovdr(DRegister dn, int i, Register rt, Condition cond) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT((i == 0) || (i == 1));
   ASSERT(rt != kNoRegister);
   ASSERT(rt != SP);
@@ -793,7 +788,6 @@
                         Register rt,
                         Register rt2,
                         Condition cond) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(dm != kNoDRegister);
   ASSERT(rt != kNoRegister);
   ASSERT(rt != SP);
@@ -814,7 +808,6 @@
                         Register rt2,
                         DRegister dm,
                         Condition cond) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(dm != kNoDRegister);
   ASSERT(rt != kNoRegister);
   ASSERT(rt != SP);
@@ -833,7 +826,6 @@
 }
 
 void Assembler::vldrs(SRegister sd, Address ad, Condition cond) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(sd != kNoSRegister);
   ASSERT(cond != kNoCondition);
   int32_t encoding = (static_cast<int32_t>(cond) << kConditionShift) | B27 |
@@ -844,7 +836,6 @@
 }
 
 void Assembler::vstrs(SRegister sd, Address ad, Condition cond) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(static_cast<Register>(ad.encoding_ & (0xf << kRnShift)) != PC);
   ASSERT(sd != kNoSRegister);
   ASSERT(cond != kNoCondition);
@@ -856,7 +847,6 @@
 }
 
 void Assembler::vldrd(DRegister dd, Address ad, Condition cond) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(dd != kNoDRegister);
   ASSERT(cond != kNoCondition);
   int32_t encoding = (static_cast<int32_t>(cond) << kConditionShift) | B27 |
@@ -867,7 +857,6 @@
 }
 
 void Assembler::vstrd(DRegister dd, Address ad, Condition cond) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(static_cast<Register>(ad.encoding_ & (0xf << kRnShift)) != PC);
   ASSERT(dd != kNoDRegister);
   ASSERT(cond != kNoCondition);
@@ -884,7 +873,6 @@
                                  Register base,
                                  SRegister start,
                                  uint32_t count) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(base != kNoRegister);
   ASSERT(cond != kNoCondition);
   ASSERT(start != kNoSRegister);
@@ -904,7 +892,6 @@
                                  Register base,
                                  DRegister start,
                                  int32_t count) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(base != kNoRegister);
   ASSERT(cond != kNoCondition);
   ASSERT(start != kNoDRegister);
@@ -966,7 +953,6 @@
                            SRegister sd,
                            SRegister sn,
                            SRegister sm) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(sd != kNoSRegister);
   ASSERT(sn != kNoSRegister);
   ASSERT(sm != kNoSRegister);
@@ -986,7 +972,6 @@
                            DRegister dd,
                            DRegister dn,
                            DRegister dm) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(dd != kNoDRegister);
   ASSERT(dn != kNoDRegister);
   ASSERT(dm != kNoDRegister);
@@ -1149,7 +1134,6 @@
                           int32_t opcode,
                           SRegister sd,
                           DRegister dm) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(sd != kNoSRegister);
   ASSERT(dm != kNoDRegister);
   ASSERT(cond != kNoCondition);
@@ -1165,7 +1149,6 @@
                           int32_t opcode,
                           DRegister dd,
                           SRegister sm) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(dd != kNoDRegister);
   ASSERT(sm != kNoSRegister);
   ASSERT(cond != kNoCondition);
@@ -1234,7 +1217,6 @@
 }
 
 void Assembler::vmrs(Register rd, Condition cond) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT(cond != kNoCondition);
   int32_t encoding = (static_cast<int32_t>(cond) << kConditionShift) | B27 |
                      B26 | B25 | B23 | B22 | B21 | B20 | B16 |
@@ -2526,24 +2508,16 @@
   PushList(kAbiPreservedCpuRegs);
 
   const DRegister firstd = EvenDRegisterOf(kAbiFirstPreservedFpuReg);
-  if (TargetCPUFeatures::vfp_supported()) {
     ASSERT(2 * kAbiPreservedFpuRegCount < 16);
     // Save FPU registers. 2 D registers per Q register.
     vstmd(DB_W, SP, firstd, 2 * kAbiPreservedFpuRegCount);
-  } else {
-    sub(SP, SP, Operand(kAbiPreservedFpuRegCount * kFpuRegisterSize));
-  }
 }
 
 void Assembler::PopNativeCalleeSavedRegisters() {
   const DRegister firstd = EvenDRegisterOf(kAbiFirstPreservedFpuReg);
   // Restore C++ ABI callee-saved registers.
-  if (TargetCPUFeatures::vfp_supported()) {
-    // Restore FPU registers. 2 D registers per Q register.
-    vldmd(IA_W, SP, firstd, 2 * kAbiPreservedFpuRegCount);
-  } else {
-    AddImmediate(SP, kAbiPreservedFpuRegCount * kFpuRegisterSize);
-  }
+  // Restore FPU registers. 2 D registers per Q register.
+  vldmd(IA_W, SP, firstd, 2 * kAbiPreservedFpuRegCount);
   // Restore CPU registers.
   PopList(kAbiPreservedCpuRegs);
 }
@@ -3000,17 +2974,8 @@
                                 Register tmp1,
                                 Register tmp2,
                                 DRegister dtmp) {
-  if (TargetCPUFeatures::vfp_supported()) {
     LoadDFromOffset(dtmp, src, target::Double::value_offset() - kHeapObjectTag);
     StoreDToOffset(dtmp, dst, target::Double::value_offset() - kHeapObjectTag);
-  } else {
-    LoadFieldFromOffset(tmp1, src, target::Double::value_offset());
-    LoadFieldFromOffset(tmp2, src,
-                        target::Double::value_offset() + target::kWordSize);
-    StoreFieldToOffset(tmp1, dst, target::Double::value_offset());
-    StoreFieldToOffset(tmp2, dst,
-                       target::Double::value_offset() + target::kWordSize);
-  }
 }
 
 void Assembler::CopyFloat32x4Field(Register dst,
@@ -3215,7 +3180,6 @@
   if (TargetCPUFeatures::integer_division_supported()) {
     sdiv(result, left, right);
   } else {
-    ASSERT(TargetCPUFeatures::vfp_supported());
     SRegister stmpl = EvenSRegisterOf(tmpl);
     SRegister stmpr = EvenSRegisterOf(tmpr);
     vmovsr(stmpl, left);
@@ -3298,7 +3262,6 @@
   COMPILE_ASSERT((kDartVolatileCpuRegs & (1 << PP)) == 0);
 
   // Preserve all volatile FPU registers.
-  if (TargetCPUFeatures::vfp_supported()) {
     DRegister firstv = EvenDRegisterOf(kDartFirstVolatileFpuReg);
     DRegister lastv = OddDRegisterOf(kDartLastVolatileFpuReg);
     if ((lastv - firstv + 1) >= 16) {
@@ -3308,7 +3271,6 @@
     } else {
       vstmd(DB_W, SP, firstv, lastv - firstv + 1);
     }
-  }
 
   ReserveAlignedFrameSpace(frame_space);
 }
@@ -3318,9 +3280,7 @@
   // and ensure proper alignment of the stack frame.
   // We need to restore it before restoring registers.
   const intptr_t kPushedFpuRegisterSize =
-      TargetCPUFeatures::vfp_supported()
-          ? kDartVolatileFpuRegCount * kFpuRegisterSize
-          : 0;
+      kDartVolatileFpuRegCount * kFpuRegisterSize;
 
   COMPILE_ASSERT(PP < FP);
   COMPILE_ASSERT((kDartVolatileCpuRegs & (1 << PP)) == 0);
@@ -3331,7 +3291,6 @@
   AddImmediate(SP, FP, -kPushedRegistersSize);
 
   // Restore all volatile FPU registers.
-  if (TargetCPUFeatures::vfp_supported()) {
     DRegister firstv = EvenDRegisterOf(kDartFirstVolatileFpuReg);
     DRegister lastv = OddDRegisterOf(kDartLastVolatileFpuReg);
     if ((lastv - firstv + 1) >= 16) {
@@ -3341,7 +3300,6 @@
     } else {
       vldmd(IA_W, SP, firstv, lastv - firstv + 1);
     }
-  }
 
   // Restore volatile CPU registers.
   RESTORES_LR_FROM_FRAME(
diff --git a/runtime/vm/compiler/assembler/assembler_arm64_test.cc b/runtime/vm/compiler/assembler/assembler_arm64_test.cc
index a54fe57..97ce2ab 100644
--- a/runtime/vm/compiler/assembler/assembler_arm64_test.cc
+++ b/runtime/vm/compiler/assembler/assembler_arm64_test.cc
@@ -15,6 +15,13 @@
 namespace compiler {
 #define __ assembler->
 
+#if defined(PRODUCT)
+#define EXPECT_DISASSEMBLY(expected)
+#else
+#define EXPECT_DISASSEMBLY(expected)                                           \
+  EXPECT_STREQ(expected, test->RelativeDisassembly())
+#endif
+
 ASSEMBLER_TEST_GENERATE(Simple, assembler) {
   __ add(R0, ZR, Operand(ZR));
   __ add(R0, R0, Operand(42));
@@ -24,6 +31,10 @@
 ASSEMBLER_TEST_RUN(Simple, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "add r0, zr, zr\n"
+      "add r0, r0, #0x2a\n"
+      "ret\n");
 }
 
 // Move wide immediate tests.
@@ -36,6 +47,9 @@
 ASSEMBLER_TEST_RUN(Movz0, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Movz1, assembler) {
@@ -47,6 +61,10 @@
 ASSEMBLER_TEST_RUN(Movz1, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42LL << 16, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "movz r0, #0x2a lsl 16\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Movz2, assembler) {
@@ -57,6 +75,9 @@
 ASSEMBLER_TEST_RUN(Movz2, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42LL << 32, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a lsl 32\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Movz3, assembler) {
@@ -67,6 +88,9 @@
 ASSEMBLER_TEST_RUN(Movz3, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42LL << 48, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a lsl 48\n"
+      "ret\n");
 }
 
 // movn
@@ -78,6 +102,9 @@
 ASSEMBLER_TEST_RUN(Movn0, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(~42LL, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Movn1, assembler) {
@@ -88,6 +115,9 @@
 ASSEMBLER_TEST_RUN(Movn1, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(~(42LL << 16), EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r0, #0x2a lsl 16\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Movn2, assembler) {
@@ -98,6 +128,9 @@
 ASSEMBLER_TEST_RUN(Movn2, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(~(42LL << 32), EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r0, #0x2a lsl 32\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Movn3, assembler) {
@@ -108,6 +141,9 @@
 ASSEMBLER_TEST_RUN(Movn3, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(~(42LL << 48), EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r0, #0x2a lsl 48\n"
+      "ret\n");
 }
 
 // movk
@@ -121,6 +157,10 @@
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42LL | (1LL << 48),
             EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x1 lsl 48\n"
+      "movk r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Movk1, assembler) {
@@ -133,6 +173,10 @@
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ((42LL << 16) | 1,
             EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x1\n"
+      "movk r0, #0x2a lsl 16\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Movk2, assembler) {
@@ -145,6 +189,10 @@
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ((42LL << 32) | 1,
             EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x1\n"
+      "movk r0, #0x2a lsl 32\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Movk3, assembler) {
@@ -157,6 +205,10 @@
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ((42LL << 48) | 1,
             EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x1\n"
+      "movk r0, #0x2a lsl 48\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(MovzBig, assembler) {
@@ -167,6 +219,9 @@
 ASSEMBLER_TEST_RUN(MovzBig, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0x8000, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x8000\n"
+      "ret\n");
 }
 
 // add tests.
@@ -180,6 +235,11 @@
 ASSEMBLER_TEST_RUN(AddReg, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x14\n"
+      "movz r1, #0x16\n"
+      "add r0, r0, r1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(AddLSLReg, assembler) {
@@ -192,6 +252,11 @@
 ASSEMBLER_TEST_RUN(AddLSLReg, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x14\n"
+      "movz r1, #0xb\n"
+      "add r0, r0, r1 lsl #1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(AddLSRReg, assembler) {
@@ -204,6 +269,11 @@
 ASSEMBLER_TEST_RUN(AddLSRReg, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x14\n"
+      "movz r1, #0x2c\n"
+      "add r0, r0, r1 lsr #1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(AddASRReg, assembler) {
@@ -216,6 +286,11 @@
 ASSEMBLER_TEST_RUN(AddASRReg, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x14\n"
+      "movz r1, #0x2c\n"
+      "add r0, r0, r1 asr #1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(AddASRNegReg, assembler) {
@@ -229,6 +304,12 @@
 ASSEMBLER_TEST_RUN(AddASRNegReg, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2b\n"
+      "movn r1, #0x0\n"
+      "add r1, zr, r1 lsl #3\n"
+      "add r0, r0, r1 asr #3\n"
+      "ret\n");
 }
 
 // TODO(zra): test other sign extension modes.
@@ -243,6 +324,12 @@
 ASSEMBLER_TEST_RUN(AddExtReg, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2b\n"
+      "movz r1, #0xffff\n"
+      "movk r1, #0xffff lsl 16\n"
+      "add r0, r0, r1 sxtw\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(AddCarryInOut, assembler) {
@@ -258,6 +345,14 @@
 ASSEMBLER_TEST_RUN(AddCarryInOut, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(1, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r2, #0x0\n"
+      "movz r1, #0x1\n"
+      "movz r0, #0x0\n"
+      "adds ip0, r2, r1\n"
+      "adcs ip0, r2, r0\n"
+      "adc r0, r0, r0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(SubCarryInOut, assembler) {
@@ -272,6 +367,13 @@
 ASSEMBLER_TEST_RUN(SubCarryInOut, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-1, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x1\n"
+      "movz r0, #0x0\n"
+      "subs ip0, r0, r1\n"
+      "sbcs ip0, r0, r0\n"
+      "sbc r0, r0, r0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Overflow, assembler) {
@@ -288,6 +390,15 @@
 ASSEMBLER_TEST_RUN(Overflow, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x0\n"
+      "movz r1, #0x1\n"
+      "movn r2, #0x0\n"
+      "mov r3, 0x7fffffffffffffff\n"
+      "adds ip0, r2, r1\n"
+      "adcs ip0, r3, r0\n"
+      "csinc r0, r0, r0, vs\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(WordAddCarryInOut, assembler) {
@@ -303,6 +414,14 @@
 ASSEMBLER_TEST_RUN(WordAddCarryInOut, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(1, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r2, #0x0\n"
+      "movz r1, #0x1\n"
+      "movz r0, #0x0\n"
+      "addws ip0, r2, r1\n"
+      "adcws ip0, r2, r0\n"
+      "adcw r0, r0, r0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(WordSubCarryInOut, assembler) {
@@ -317,6 +436,13 @@
 ASSEMBLER_TEST_RUN(WordSubCarryInOut, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0x0FFFFFFFF, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x1\n"
+      "movz r0, #0x0\n"
+      "subws ip0, r0, r1\n"
+      "sbcws ip0, r0, r0\n"
+      "sbcw r0, r0, r0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(WordOverflow, assembler) {
@@ -333,6 +459,15 @@
 ASSEMBLER_TEST_RUN(WordOverflow, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x0\n"
+      "movz r1, #0x1\n"
+      "mov r2, 0xffffffff\n"
+      "mov r3, 0x7fffffff\n"
+      "addws ip0, r2, r1\n"
+      "adcws ip0, r3, r0\n"
+      "csinc r0, r0, r0, vs\n"
+      "ret\n");
 }
 
 // Loads and Stores.
@@ -353,6 +488,16 @@
 ASSEMBLER_TEST_RUN(SimpleLoadStore, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "sub csp, csp, #0x10\n"
+      "movz r0, #0x2b\n"
+      "movz r1, #0x2a\n"
+      "str r1, [r15, #-8]!\n"
+      "ldr r0, [r15], #8 !\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(SimpleLoadStoreHeapTag, assembler) {
@@ -369,6 +514,16 @@
 ASSEMBLER_TEST_RUN(SimpleLoadStoreHeapTag, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz r0, #0x2b\n"
+      "movz r1, #0x2a\n"
+      "add r2, r15, #0x1\n"
+      "str r1, [r2, #-1]\n"
+      "ldr r0, [r2, #-1]\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadStoreLargeIndex, assembler) {
@@ -392,6 +547,17 @@
 ASSEMBLER_TEST_RUN(LoadStoreLargeIndex, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "sub csp, csp, #0x100\n"
+      "movz r0, #0x2b\n"
+      "movz r1, #0x2a\n"
+      "str r1, [r15, #-256]!\n"
+      "ldr r0, [r15], #248 !\n"
+      "add r15, r15, #0x8\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadStoreLargeOffset, assembler) {
@@ -410,6 +576,18 @@
 ASSEMBLER_TEST_RUN(LoadStoreLargeOffset, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz r0, #0x2b\n"
+      "movz r1, #0x2a\n"
+      "sub r15, r15, #0x1000\n"
+      "and csp, r15, 0xfffffffffffffff0\n"
+      "str r1, [r15, #4096]\n"
+      "add r15, r15, #0x1000\n"
+      "ldr r0, [r15]\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadStoreExtReg, assembler) {
@@ -432,6 +610,20 @@
 ASSEMBLER_TEST_RUN(LoadStoreExtReg, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz r0, #0x2b\n"
+      "movz r1, #0x2a\n"
+      "movz r2, #0xfff8\n"
+      "movk r2, #0xffff lsl 16\n"
+      "str r1, [r15, r2 sxtw]\n"
+      "sub r15, r15, #0x8\n"
+      "and csp, r15, 0xfffffffffffffff0\n"
+      "ldr r0, [r15]\n"
+      "add r15, r15, #0x8\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadStoreScaledReg, assembler) {
@@ -452,6 +644,19 @@
 ASSEMBLER_TEST_RUN(LoadStoreScaledReg, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz r0, #0x2b\n"
+      "movz r1, #0x2a\n"
+      "movz r2, #0xa\n"
+      "sub r15, r15, #0x50\n"
+      "and csp, r15, 0xfffffffffffffff0\n"
+      "str r1, [r15, r2 uxtx scaled]\n"
+      "ldr r0, [r15, r2 uxtx scaled]\n"
+      "add r15, r15, #0x50\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadSigned32Bit, assembler) {
@@ -471,6 +676,16 @@
 ASSEMBLER_TEST_RUN(LoadSigned32Bit, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-1, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "sub csp, csp, #0x10\n"
+      "mov r1, 0xffffffff\n"
+      "strw r1, [r15, #-4]!\n"
+      "ldrsw r0, [r15]\n"
+      "ldrsw r1, [r15], #4 !\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(SimpleLoadStorePair, assembler) {
@@ -491,6 +706,17 @@
 ASSEMBLER_TEST_RUN(SimpleLoadStorePair, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(1, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "sub csp, csp, #0x10\n"
+      "movz r2, #0x2b\n"
+      "movz r3, #0x2a\n"
+      "stp r2, r3, [r15, #-16]!\n"
+      "ldp r0, r1, [r15], #16 !\n"
+      "sub r0, r0, r1\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadStorePairOffset, assembler) {
@@ -510,6 +736,19 @@
 ASSEMBLER_TEST_RUN(LoadStorePairOffset, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(1, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz r2, #0x2b\n"
+      "movz r3, #0x2a\n"
+      "sub r15, r15, #0x20\n"
+      "and csp, r15, 0xfffffffffffffff0\n"
+      "stp r2, r3, [r15, #16]\n"
+      "ldp r0, r1, [r15, #16]\n"
+      "add r15, r15, #0x20\n"
+      "sub r0, r0, r1\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(PushRegisterPair, assembler) {
@@ -527,6 +766,16 @@
   EXPECT(test != NULL);
   typedef int (*PushRegisterPair)() DART_UNUSED;
   EXPECT_EQ(12, EXECUTE_TEST_CODE_INT64(PushRegisterPair, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz r2, #0xc\n"
+      "movz r3, #0x15\n"
+      "stp r2, r3, [r15, #-16]!\n"
+      "ldr r0, [r15], #8 !\n"
+      "ldr r1, [r15], #8 !\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(PushRegisterPairReversed, assembler) {
@@ -545,6 +794,16 @@
   typedef int (*PushRegisterPairReversed)() DART_UNUSED;
   EXPECT_EQ(12,
             EXECUTE_TEST_CODE_INT64(PushRegisterPairReversed, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz r3, #0xc\n"
+      "movz r2, #0x15\n"
+      "stp r3, r2, [r15, #-16]!\n"
+      "ldr r0, [r15], #8 !\n"
+      "ldr r1, [r15], #8 !\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(PopRegisterPair, assembler) {
@@ -562,6 +821,16 @@
   EXPECT(test != NULL);
   typedef int (*PopRegisterPair)() DART_UNUSED;
   EXPECT_EQ(12, EXECUTE_TEST_CODE_INT64(PopRegisterPair, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz r2, #0xc\n"
+      "movz r3, #0x15\n"
+      "str r3, [r15, #-8]!\n"
+      "str r2, [r15, #-8]!\n"
+      "ldp r0, r1, [r15], #16 !\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(PopRegisterPairReversed, assembler) {
@@ -580,6 +849,16 @@
   typedef int (*PopRegisterPairReversed)() DART_UNUSED;
   EXPECT_EQ(12,
             EXECUTE_TEST_CODE_INT64(PopRegisterPairReversed, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz r3, #0xc\n"
+      "movz r2, #0x15\n"
+      "str r3, [r15, #-8]!\n"
+      "str r2, [r15, #-8]!\n"
+      "ldp r1, r0, [r15], #16 !\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Semaphore, assembler) {
@@ -602,6 +881,19 @@
   EXPECT(test != NULL);
   typedef intptr_t (*Semaphore)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Semaphore, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz r0, #0x28\n"
+      "movz r1, #0x2a\n"
+      "str r0, [r15, #-8]!\n"
+      "ldxr r0, r15\n"
+      "stxr ip0, r1, r15\n"
+      "cmp ip0, #0x0\n"
+      "bne -12\n"
+      "ldr r0, [r15], #8 !\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FailedSemaphore, assembler) {
@@ -622,6 +914,19 @@
   EXPECT(test != NULL);
   typedef intptr_t (*FailedSemaphore)() DART_UNUSED;
   EXPECT_EQ(41, EXECUTE_TEST_CODE_INT64(FailedSemaphore, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz r0, #0x28\n"
+      "movz r1, #0x2a\n"
+      "str r0, [r15, #-8]!\n"
+      "ldxr r0, r15\n"
+      "clrex\n"
+      "stxr ip0, r1, r15\n"
+      "ldr r0, [r15], #8 !\n"
+      "add r0, r0, ip0\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Semaphore32, assembler) {
@@ -653,6 +958,21 @@
   // is unchanged at 40.
   EXPECT_EQ(42 + (DART_INT64_C(40) << 32),
             EXECUTE_TEST_CODE_INT64(Semaphore32, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz r0, #0x28\n"
+      "add r0, r0, r0 lsl #32\n"
+      "str r0, [r15, #-8]!\n"
+      "movz r0, #0x28\n"
+      "movz r1, #0x2a\n"
+      "ldxrw r0, r15\n"
+      "stxrw ip0, r1, r15\n"
+      "cmp ip0, #0x0\n"
+      "bne -12\n"
+      "ldr r0, [r15], #8 !\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FailedSemaphore32, assembler) {
@@ -680,6 +1000,21 @@
   // unchanged at 40.
   EXPECT_EQ(41 + (DART_INT64_C(40) << 32),
             EXECUTE_TEST_CODE_INT64(FailedSemaphore32, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz r0, #0x28\n"
+      "add r0, r0, r0 lsl #32\n"
+      "str r0, [r15, #-8]!\n"
+      "movz r0, #0x28\n"
+      "movz r1, #0x2a\n"
+      "ldxrw r0, r15\n"
+      "clrex\n"
+      "stxrw ip0, r1, r15\n"
+      "ldr r0, [r15], #8 !\n"
+      "add r0, r0, ip0\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadAcquireStoreRelease, assembler) {
@@ -736,6 +1071,68 @@
   typedef intptr_t (*LoadAcquireStoreRelease)() DART_UNUSED;
   EXPECT_EQ(0x42,
             EXECUTE_TEST_CODE_INT64(LoadAcquireStoreRelease, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "stp fp, lr, [r15, #-16]!\n"
+      "mov fp, r15\n"
+      "movz ip0, #0x7788\n"
+      "movk ip0, #0x5566 lsl 16\n"
+      "movk ip0, #0x3344 lsl 32\n"
+      "movk ip0, #0x1122 lsl 48\n"
+      "str ip0, [r15, #-8]!\n"
+      "ldar r1, r15\n"
+      "movz ip1, #0x7788\n"
+      "movk ip1, #0x5566 lsl 16\n"
+      "movk ip1, #0x3344 lsl 32\n"
+      "movk ip1, #0x1122 lsl 48\n"
+      "cmp r1, ip1\n"
+      "bne +164\n"
+      "add r15, r15, #0x8\n"
+      "movz ip0, #0x7788\n"
+      "movk ip0, #0x5566 lsl 16\n"
+      "movk ip0, #0x3344 lsl 32\n"
+      "movk ip0, #0x1122 lsl 48\n"
+      "str ip0, [r15, #-8]!\n"
+      "ldarw r1, r15\n"
+      "movz ip1, #0x7788\n"
+      "movk ip1, #0x5566 lsl 16\n"
+      "cmp r1, ip1\n"
+      "bne +120\n"
+      "add r15, r15, #0x8\n"
+      "movz ip0, #0x0\n"
+      "str ip0, [r15, #-8]!\n"
+      "movz r1, #0x7788\n"
+      "movk r1, #0x5566 lsl 16\n"
+      "movk r1, #0x3344 lsl 32\n"
+      "movk r1, #0x1122 lsl 48\n"
+      "stlr r1, r15\n"
+      "ldr r1, [r15], #8 !\n"
+      "movz ip1, #0x7788\n"
+      "movk ip1, #0x5566 lsl 16\n"
+      "movk ip1, #0x3344 lsl 32\n"
+      "movk ip1, #0x1122 lsl 48\n"
+      "cmp r1, ip1\n"
+      "bne +60\n"
+      "movz ip0, #0x0\n"
+      "str ip0, [r15, #-8]!\n"
+      "movz r1, #0x7788\n"
+      "movk r1, #0x5566 lsl 16\n"
+      "movk r1, #0x3344 lsl 32\n"
+      "movk r1, #0x1122 lsl 48\n"
+      "stlrw r1, r15\n"
+      "ldr r1, [r15], #8 !\n"
+      "movz ip1, #0x7788\n"
+      "movk ip1, #0x5566 lsl 16\n"
+      "cmp r1, ip1\n"
+      "bne +12\n"
+      "movz r0, #0x42\n"
+      "b +8\n"
+      "movz r0, #0x84\n"
+      "mov r15, fp\n"
+      "ldp fp, lr, [r15], #16 !\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 // Logical register operations.
@@ -749,6 +1146,11 @@
 ASSEMBLER_TEST_RUN(AndRegs, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x2b\n"
+      "movz r2, #0x2a\n"
+      "and r0, r1, r2\n"
+      "ret\n");
 }
 
 constexpr uint64_t kU64MinusOne = 0xffffffffffffffffull;
@@ -1108,6 +1510,123 @@
 #undef FOR_EACH_LSR_32_TESTS_LIST
 #undef FOR_EACH_ASR_32_TESTS_LIST
 
+ASSEMBLER_TEST_GENERATE(LslImmediate, assembler) {
+  __ LslImmediate(R0, R0, 1);
+  __ LslImmediate(R0, R0, 2);
+  __ LslImmediate(R0, R0, 3);
+  __ LslImmediate(R0, R0, 4);
+  __ LslImmediate(R0, R0, 60);
+  __ LslImmediate(R0, R0, 61);
+  __ LslImmediate(R0, R0, 62);
+  __ LslImmediate(R0, R0, 63);
+  __ LslImmediate(R0, R0, 1, kFourBytes);
+  __ LslImmediate(R0, R0, 2, kFourBytes);
+  __ LslImmediate(R0, R0, 3, kFourBytes);
+  __ LslImmediate(R0, R0, 4, kFourBytes);
+  __ LslImmediate(R0, R0, 28, kFourBytes);
+  __ LslImmediate(R0, R0, 29, kFourBytes);
+  __ LslImmediate(R0, R0, 30, kFourBytes);
+  __ LslImmediate(R0, R0, 31, kFourBytes);
+}
+
+ASSEMBLER_TEST_RUN(LslImmediate, test) {
+  EXPECT_DISASSEMBLY(
+      "lsl r0, r0, #1\n"
+      "lsl r0, r0, #2\n"
+      "lsl r0, r0, #3\n"
+      "lsl r0, r0, #4\n"
+      "lsl r0, r0, #60\n"
+      "lsl r0, r0, #61\n"
+      "lsl r0, r0, #62\n"
+      "lsl r0, r0, #63\n"
+      "lslw r0, r0, #1\n"
+      "lslw r0, r0, #2\n"
+      "lslw r0, r0, #3\n"
+      "lslw r0, r0, #4\n"
+      "lslw r0, r0, #28\n"
+      "lslw r0, r0, #29\n"
+      "lslw r0, r0, #30\n"
+      "lslw r0, r0, #31\n");
+}
+
+ASSEMBLER_TEST_GENERATE(LsrImmediate, assembler) {
+  __ LsrImmediate(R0, R0, 1);
+  __ LsrImmediate(R0, R0, 2);
+  __ LsrImmediate(R0, R0, 3);
+  __ LsrImmediate(R0, R0, 4);
+  __ LsrImmediate(R0, R0, 60);
+  __ LsrImmediate(R0, R0, 61);
+  __ LsrImmediate(R0, R0, 62);
+  __ LsrImmediate(R0, R0, 63);
+  __ LsrImmediate(R0, R0, 1, kFourBytes);
+  __ LsrImmediate(R0, R0, 2, kFourBytes);
+  __ LsrImmediate(R0, R0, 3, kFourBytes);
+  __ LsrImmediate(R0, R0, 4, kFourBytes);
+  __ LsrImmediate(R0, R0, 28, kFourBytes);
+  __ LsrImmediate(R0, R0, 29, kFourBytes);
+  __ LsrImmediate(R0, R0, 30, kFourBytes);
+  __ LsrImmediate(R0, R0, 31, kFourBytes);
+}
+
+ASSEMBLER_TEST_RUN(LsrImmediate, test) {
+  EXPECT_DISASSEMBLY(
+      "lsr r0, r0, #1\n"
+      "lsr r0, r0, #2\n"
+      "lsr r0, r0, #3\n"
+      "lsr r0, r0, #4\n"
+      "lsr r0, r0, #60\n"
+      "lsr r0, r0, #61\n"
+      "lsr r0, r0, #62\n"
+      "lsr r0, r0, #63\n"
+      "lsrw r0, r0, #1\n"
+      "lsrw r0, r0, #2\n"
+      "lsrw r0, r0, #3\n"
+      "lsrw r0, r0, #4\n"
+      "lsrw r0, r0, #28\n"
+      "lsrw r0, r0, #29\n"
+      "lsrw r0, r0, #30\n"
+      "lsrw r0, r0, #31\n");
+}
+
+ASSEMBLER_TEST_GENERATE(AsrImmediate, assembler) {
+  __ AsrImmediate(R0, R0, 1);
+  __ AsrImmediate(R0, R0, 2);
+  __ AsrImmediate(R0, R0, 3);
+  __ AsrImmediate(R0, R0, 4);
+  __ AsrImmediate(R0, R0, 60);
+  __ AsrImmediate(R0, R0, 61);
+  __ AsrImmediate(R0, R0, 62);
+  __ AsrImmediate(R0, R0, 63);
+  __ AsrImmediate(R0, R0, 1, kFourBytes);
+  __ AsrImmediate(R0, R0, 2, kFourBytes);
+  __ AsrImmediate(R0, R0, 3, kFourBytes);
+  __ AsrImmediate(R0, R0, 4, kFourBytes);
+  __ AsrImmediate(R0, R0, 28, kFourBytes);
+  __ AsrImmediate(R0, R0, 29, kFourBytes);
+  __ AsrImmediate(R0, R0, 30, kFourBytes);
+  __ AsrImmediate(R0, R0, 31, kFourBytes);
+}
+
+ASSEMBLER_TEST_RUN(AsrImmediate, test) {
+  EXPECT_DISASSEMBLY(
+      "asr r0, r0, #1\n"
+      "asr r0, r0, #2\n"
+      "asr r0, r0, #3\n"
+      "asr r0, r0, #4\n"
+      "asr r0, r0, #60\n"
+      "asr r0, r0, #61\n"
+      "asr r0, r0, #62\n"
+      "asr r0, r0, #63\n"
+      "asrw r0, r0, #1\n"
+      "asrw r0, r0, #2\n"
+      "asrw r0, r0, #3\n"
+      "asrw r0, r0, #4\n"
+      "asrw r0, r0, #28\n"
+      "asrw r0, r0, #29\n"
+      "asrw r0, r0, #30\n"
+      "asrw r0, r0, #31\n");
+}
+
 ASSEMBLER_TEST_GENERATE(AndShiftRegs, assembler) {
   __ movz(R1, Immediate(42), 0);
   __ movz(R2, Immediate(21), 0);
@@ -1118,6 +1637,11 @@
 ASSEMBLER_TEST_RUN(AndShiftRegs, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x2a\n"
+      "movz r2, #0x15\n"
+      "and r0, r1, r2 lsl #1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(BicRegs, assembler) {
@@ -1130,6 +1654,11 @@
 ASSEMBLER_TEST_RUN(BicRegs, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x2a\n"
+      "movz r2, #0x5\n"
+      "bic r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(OrrRegs, assembler) {
@@ -1142,6 +1671,11 @@
 ASSEMBLER_TEST_RUN(OrrRegs, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x20\n"
+      "movz r2, #0xa\n"
+      "orr r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(OrnRegs, assembler) {
@@ -1155,6 +1689,12 @@
 ASSEMBLER_TEST_RUN(OrnRegs, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x20\n"
+      "movn r2, #0x0\n"
+      "movk r2, #0xffd5\n"
+      "orn r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(EorRegs, assembler) {
@@ -1167,6 +1707,11 @@
 ASSEMBLER_TEST_RUN(EorRegs, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0xffd5\n"
+      "movz r2, #0xffff\n"
+      "eor r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(EonRegs, assembler) {
@@ -1179,6 +1724,11 @@
 ASSEMBLER_TEST_RUN(EonRegs, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0xffd5\n"
+      "movn r2, #0xffff\n"
+      "eon r0, r1, r2\n"
+      "ret\n");
 }
 
 // Logical immediate operations.
@@ -1191,6 +1741,10 @@
 ASSEMBLER_TEST_RUN(AndImm, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x2a\n"
+      "and r0, r1, 0xaaaaaaaaaaaaaaaa\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(AndImmCsp, assembler) {
@@ -1207,6 +1761,14 @@
 ASSEMBLER_TEST_RUN(AndImmCsp, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(32, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov ip0, csp\n"
+      "sub ip1, csp, #0x1f\n"
+      "and csp, ip1, 0xfffffffffffffff0\n"
+      "mov r0, csp\n"
+      "sub r0, ip0, r0\n"
+      "mov csp, ip0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(AndOneImm, assembler) {
@@ -1218,6 +1780,10 @@
 ASSEMBLER_TEST_RUN(AndOneImm, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(1, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x2b\n"
+      "and r0, r1, 0x1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(OrrImm, assembler) {
@@ -1233,6 +1799,14 @@
 ASSEMBLER_TEST_RUN(OrrImm, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x0\n"
+      "movz r2, #0x3f\n"
+      "movz r3, #0xa\n"
+      "orr r1, r1, 0x20002000200020\n"
+      "orr r1, r1, r3\n"
+      "and r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(EorImm, assembler) {
@@ -1247,6 +1821,13 @@
 ASSEMBLER_TEST_RUN(EorImm, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r0, #0x0\n"
+      "movk r0, #0xffd5\n"
+      "movz r1, #0x3f\n"
+      "eor r0, r0, 0x3f3f3f3f3f3f3f3f\n"
+      "and r0, r0, r1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Clz, assembler) {
@@ -1277,6 +1858,26 @@
 ASSEMBLER_TEST_RUN(Clz, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "clz r1, zr\n"
+      "cmp r1, #0x40\n"
+      "bne +60\n"
+      "movz r2, #0x2a\n"
+      "clz r2, r2\n"
+      "cmp r2, #0x3a\n"
+      "bne +44\n"
+      "movn r0, #0x0\n"
+      "clz r1, r0\n"
+      "cmp r1, #0x0\n"
+      "bne +28\n"
+      "add r0, zr, r0 lsr #3\n"
+      "clz r1, r0\n"
+      "cmp r1, #0x3\n"
+      "bne +12\n"
+      "mov r0, zr\n"
+      "ret\n"
+      "movz r0, #0x1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Clzw, assembler) {
@@ -1315,6 +1916,34 @@
 ASSEMBLER_TEST_RUN(Clzw, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "clzw r1, zr\n"
+      "cmp r1, #0x20\n"
+      "bne +92\n"
+      "movz r2, #0x2a\n"
+      "clzw r2, r2\n"
+      "cmp r2, #0x1a\n"
+      "bne +76\n"
+      "movn r0, #0x0\n"
+      "clzw r1, r0\n"
+      "cmp r1, #0x0\n"
+      "bne +60\n"
+      "add r0, zr, r0 lsr #35\n"
+      "clzw r1, r0\n"
+      "cmp r1, #0x3\n"
+      "bne +44\n"
+      "mov r0, 0xffffffff0fffffff\n"
+      "clzw r1, r0\n"
+      "cmp r1, #0x4\n"
+      "bne +28\n"
+      "mov r0, 0xffffffff\n"
+      "clzw r1, r0\n"
+      "cmp r1, #0x0\n"
+      "bne +12\n"
+      "mov r0, zr\n"
+      "ret\n"
+      "movz r0, #0x1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Rbit, assembler) {
@@ -1328,6 +1957,10 @@
   typedef int64_t (*Int64Return)() DART_UNUSED;
   const int64_t expected = 0xa800000000000000;
   EXPECT_EQ(expected, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x15\n"
+      "rbit r0, r0\n"
+      "ret\n");
 }
 
 // Comparisons, branching.
@@ -1343,6 +1976,11 @@
 ASSEMBLER_TEST_RUN(BranchALForward, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "b +8\n"
+      "movz r0, #0x0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(BranchALBackwards, assembler) {
@@ -1364,6 +2002,15 @@
 ASSEMBLER_TEST_RUN(BranchALBackwards, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "b +16\n"
+      "movz r0, #0x0\n"
+      "ret\n"
+      "movz r0, #0x0\n"
+      "b -8\n"
+      "movz r0, #0x0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CmpEqBranch, assembler) {
@@ -1383,6 +2030,14 @@
 ASSEMBLER_TEST_RUN(CmpEqBranch, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "movz r1, #0xea\n"
+      "movz r2, #0xea\n"
+      "cmp r1, r2\n"
+      "beq +8\n"
+      "movz r0, #0x0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CmpEqBranchNotTaken, assembler) {
@@ -1402,6 +2057,14 @@
 ASSEMBLER_TEST_RUN(CmpEqBranchNotTaken, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x0\n"
+      "movz r1, #0xe9\n"
+      "movz r2, #0xea\n"
+      "cmp r1, r2\n"
+      "beq +8\n"
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CmpEq1Branch, assembler) {
@@ -1420,6 +2083,13 @@
 ASSEMBLER_TEST_RUN(CmpEq1Branch, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "movz r1, #0x1\n"
+      "cmp r1, #0x1\n"
+      "beq +8\n"
+      "movz r0, #0x0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CmnEq1Branch, assembler) {
@@ -1438,6 +2108,13 @@
 ASSEMBLER_TEST_RUN(CmnEq1Branch, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "movn r1, #0x0\n"
+      "cmn r1, #0x1\n"
+      "beq +8\n"
+      "movz r0, #0x0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CmpLtBranch, assembler) {
@@ -1457,6 +2134,14 @@
 ASSEMBLER_TEST_RUN(CmpLtBranch, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "movz r1, #0xe9\n"
+      "movz r2, #0xea\n"
+      "cmp r1, r2\n"
+      "blt +8\n"
+      "movz r0, #0x0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CmpLtBranchNotTaken, assembler) {
@@ -1476,6 +2161,14 @@
 ASSEMBLER_TEST_RUN(CmpLtBranchNotTaken, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x0\n"
+      "movz r1, #0xeb\n"
+      "movz r2, #0xea\n"
+      "cmp r1, r2\n"
+      "blt +8\n"
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CmpBranchIfZero, assembler) {
@@ -1493,6 +2186,12 @@
 ASSEMBLER_TEST_RUN(CmpBranchIfZero, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "movz r1, #0x0\n"
+      "cbz r1, +8\n"
+      "movz r0, #0x0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CmpBranchIfZeroNotTaken, assembler) {
@@ -1510,6 +2209,12 @@
 ASSEMBLER_TEST_RUN(CmpBranchIfZeroNotTaken, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x0\n"
+      "movz r1, #0x1\n"
+      "cbz r1, +8\n"
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CmpBranchIfNotZero, assembler) {
@@ -1527,6 +2232,12 @@
 ASSEMBLER_TEST_RUN(CmpBranchIfNotZero, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "movz r1, #0x1\n"
+      "cbnz r1, +8\n"
+      "movz r0, #0x0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CmpBranchIfNotZeroNotTaken, assembler) {
@@ -1544,6 +2255,12 @@
 ASSEMBLER_TEST_RUN(CmpBranchIfNotZeroNotTaken, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x0\n"
+      "movz r1, #0x0\n"
+      "cbnz r1, +8\n"
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 static const int64_t kBits5And35 = (1 << 5) | (1ll << 35);
@@ -1568,6 +2285,15 @@
 ASSEMBLER_TEST_RUN(TstBranchIfZero, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "movn r1, #0x8 lsl 32\n"
+      "movk r1, #0xffdf\n"
+      "tbzw r1, #5, +8\n"
+      "movz r0, #0x0\n"
+      "tbz r1, #35, +8\n"
+      "movz r0, #0x0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(TstBranchIfZeroNotTaken, assembler) {
@@ -1585,6 +2311,13 @@
 ASSEMBLER_TEST_RUN(TstBranchIfZeroNotTaken, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x0\n"
+      "movz r1, #0x20\n"
+      "movk r1, #0x8 lsl 32\n"
+      "tbzw r1, #5, +8\n"
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(TstBranchIfNotZero, assembler) {
@@ -1607,6 +2340,15 @@
 ASSEMBLER_TEST_RUN(TstBranchIfNotZero, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "movz r1, #0x20\n"
+      "movk r1, #0x8 lsl 32\n"
+      "tbnzw r1, #5, +8\n"
+      "movz r0, #0x0\n"
+      "tbnz r1, #35, +8\n"
+      "movz r0, #0x0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(TstBranchIfNotZeroNotTaken, assembler) {
@@ -1624,6 +2366,13 @@
 ASSEMBLER_TEST_RUN(TstBranchIfNotZeroNotTaken, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x0\n"
+      "movn r1, #0x8 lsl 32\n"
+      "movk r1, #0xffdf\n"
+      "tbnzw r1, #5, +8\n"
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(TstBranchIfZeroFar, assembler) {
@@ -1689,6 +2438,20 @@
 ASSEMBLER_TEST_RUN(FcmpEqBranch, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0x4000 lsl 32\n"
+      "movk ip0, #0x406d lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "movz ip0, #0x4000 lsl 32\n"
+      "movk ip0, #0x406d lsl 48\n"
+      "fmovdr v2, ip0\n"
+      "fcmpd v1, v2\n"
+      "beq +12\n"
+      "movz ip0, #0x0\n"
+      "fmovdr v0, ip0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(TstBranchIfZeroFar1, assembler) {
@@ -1782,6 +2545,20 @@
 ASSEMBLER_TEST_RUN(FcmpEqBranchNotTaken, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x0\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0x2000 lsl 32\n"
+      "movk ip0, #0x406d lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "movz ip0, #0x4000 lsl 32\n"
+      "movk ip0, #0x406d lsl 48\n"
+      "fmovdr v2, ip0\n"
+      "fcmpd v1, v2\n"
+      "beq +12\n"
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FcmpLtBranch, assembler) {
@@ -1820,6 +2597,20 @@
 ASSEMBLER_TEST_RUN(FcmpLtBranchNotTaken, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x0\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0x6000 lsl 32\n"
+      "movk ip0, #0x406d lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "movz ip0, #0x4000 lsl 32\n"
+      "movk ip0, #0x406d lsl 48\n"
+      "fmovdr v2, ip0\n"
+      "fcmpd v1, v2\n"
+      "blt +12\n"
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FcmpzGtBranch, assembler) {
@@ -1840,6 +2631,21 @@
 ASSEMBLER_TEST_RUN(FcmpzGtBranch, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x6000 lsl 32\n"
+      "movk ip0, #0x406d lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0x2000 lsl 32\n"
+      "movk ip0, #0x406d lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fcmpd v1, #0.0\n"
+      "bgt +16\n"
+      "movz ip0, #0x0\n"
+      "fmovdr v0, ip0\n"
+      "ret\n"
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(AndsBranch, assembler) {
@@ -1859,6 +2665,14 @@
 ASSEMBLER_TEST_RUN(AndsBranch, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "movz r1, #0x2\n"
+      "movz r2, #0x1\n"
+      "ands r3, r1, r2\n"
+      "beq +8\n"
+      "movz r0, #0x0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(AndsBranchNotTaken, assembler) {
@@ -1878,6 +2692,14 @@
 ASSEMBLER_TEST_RUN(AndsBranchNotTaken, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x0\n"
+      "movz r1, #0x2\n"
+      "movz r2, #0x2\n"
+      "ands r3, r1, r2\n"
+      "beq +8\n"
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(BicsBranch, assembler) {
@@ -1897,6 +2719,14 @@
 ASSEMBLER_TEST_RUN(BicsBranch, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "movz r1, #0x2\n"
+      "movz r2, #0x2\n"
+      "bics r3, r1, r2\n"
+      "beq +8\n"
+      "movz r0, #0x0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(BicsBranchNotTaken, assembler) {
@@ -1916,6 +2746,14 @@
 ASSEMBLER_TEST_RUN(BicsBranchNotTaken, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x0\n"
+      "movz r1, #0x2\n"
+      "movz r2, #0x1\n"
+      "bics r3, r1, r2\n"
+      "beq +8\n"
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(AndisBranch, assembler) {
@@ -1934,6 +2772,13 @@
 ASSEMBLER_TEST_RUN(AndisBranch, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "movz r1, #0x2\n"
+      "ands r3, r1, 0x1\n"
+      "beq +8\n"
+      "movz r0, #0x0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(AndisBranchNotTaken, assembler) {
@@ -1952,6 +2797,13 @@
 ASSEMBLER_TEST_RUN(AndisBranchNotTaken, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x0\n"
+      "movz r1, #0x2\n"
+      "ands r3, r1, 0x2\n"
+      "beq +8\n"
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 // Address of PC-rel offset, br, blr.
@@ -2005,6 +2857,12 @@
   EXPECT(test != NULL);
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(3, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x1b\n"
+      "movz r1, #0x9\n"
+      "udiv r2, r0, r1\n"
+      "mov r0, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Sdiv, assembler) {
@@ -2020,6 +2878,13 @@
   EXPECT(test != NULL);
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-3, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x1b\n"
+      "movz r1, #0x9\n"
+      "neg r1, r1\n"
+      "sdiv r2, r0, r1\n"
+      "mov r0, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Udiv_zero, assembler) {
@@ -2034,6 +2899,12 @@
   EXPECT(test != NULL);
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x1b\n"
+      "movz r1, #0x0\n"
+      "udiv r2, r0, r1\n"
+      "mov r0, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Sdiv_zero, assembler) {
@@ -2048,6 +2919,12 @@
   EXPECT(test != NULL);
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x1b\n"
+      "movz r1, #0x0\n"
+      "sdiv r2, r0, r1\n"
+      "mov r0, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Udiv_corner, assembler) {
@@ -2062,6 +2939,12 @@
   EXPECT(test != NULL);
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x8000 lsl 48\n"
+      "movn r1, #0x0\n"
+      "udiv r2, r0, r1\n"
+      "mov r0, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Sdiv_corner, assembler) {
@@ -2077,6 +2960,12 @@
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(static_cast<int64_t>(0x8000000000000000),
             EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r3, #0x8000 lsl 48\n"
+      "movn r1, #0x0\n"
+      "sdiv r2, r3, r1\n"
+      "mov r0, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Lslv, assembler) {
@@ -2089,6 +2978,11 @@
 ASSEMBLER_TEST_RUN(Lslv, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x15\n"
+      "movz r2, #0x1\n"
+      "lsl r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Lsrv, assembler) {
@@ -2101,6 +2995,11 @@
 ASSEMBLER_TEST_RUN(Lsrv, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x54\n"
+      "movz r2, #0x1\n"
+      "lsr r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LShiftingV, assembler) {
@@ -2114,6 +3013,12 @@
 ASSEMBLER_TEST_RUN(LShiftingV, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(1, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x1\n"
+      "movz r2, #0x3f\n"
+      "lsl r1, r1, r2\n"
+      "lsr r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(RShiftingV, assembler) {
@@ -2127,6 +3032,12 @@
 ASSEMBLER_TEST_RUN(RShiftingV, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-1, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x1\n"
+      "movz r2, #0x3f\n"
+      "lsl r1, r1, r2\n"
+      "asr r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Mult_pos, assembler) {
@@ -2139,6 +3050,11 @@
 ASSEMBLER_TEST_RUN(Mult_pos, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x6\n"
+      "movz r2, #0x7\n"
+      "mul r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Mult_neg, assembler) {
@@ -2152,6 +3068,12 @@
 ASSEMBLER_TEST_RUN(Mult_neg, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x6\n"
+      "movz r2, #0x7\n"
+      "neg r2, r2\n"
+      "mul r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Smulh_pos, assembler) {
@@ -2164,6 +3086,11 @@
 ASSEMBLER_TEST_RUN(Smulh_pos, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x6\n"
+      "movz r2, #0x7\n"
+      "smulh r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Smulh_neg, assembler) {
@@ -2177,6 +3104,12 @@
 ASSEMBLER_TEST_RUN(Smulh_neg, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-1, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x6\n"
+      "movz r2, #0x7\n"
+      "neg r2, r2\n"
+      "smulh r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Umulh, assembler) {
@@ -2190,6 +3123,11 @@
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(static_cast<int64_t>(0x6fff900000000),
             EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0xffff lsl 48\n"
+      "movz r2, #0x7 lsl 48\n"
+      "umulh r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Umaddl, assembler) {
@@ -2203,6 +3141,12 @@
 ASSEMBLER_TEST_RUN(Umaddl, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0x700000001, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r1, #0x0\n"
+      "movz r2, #0x7\n"
+      "movz r3, #0x8\n"
+      "umaddl r0, r1, r2, r3\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Smaddl, assembler) {
@@ -2216,6 +3160,12 @@
 ASSEMBLER_TEST_RUN(Smaddl, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(6, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r1, #0x1\n"
+      "movz r2, #0x7\n"
+      "movz r3, #0x14\n"
+      "smaddl r0, r1, r2, r3\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Smaddl2, assembler) {
@@ -2228,6 +3178,11 @@
 ASSEMBLER_TEST_RUN(Smaddl2, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(2, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r1, #0x1\n"
+      "movn r2, #0x0\n"
+      "smull r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Smaddl3, assembler) {
@@ -2241,6 +3196,11 @@
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0xffffl * 0xffffl,
             EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0xffff\n"
+      "movz r2, #0xffff\n"
+      "smull r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(SmaddlOverflow, assembler) {
@@ -2261,6 +3221,17 @@
 ASSEMBLER_TEST_RUN(SmaddlOverflow, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0xffff\n"
+      "add r1, r1, #0x4\n"
+      "movz r2, #0x7fff\n"
+      "smull r0, r1, r2\n"
+      "asr r3, r0, #31\n"
+      "cmp r3, r0 asr #63\n"
+      "bne +8\n"
+      "ret\n"
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(SmaddlOverflow2, assembler) {
@@ -2281,6 +3252,17 @@
 ASSEMBLER_TEST_RUN(SmaddlOverflow2, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0xffff\n"
+      "movn r2, #0xffff\n"
+      "sub r2, r2, #0x3\n"
+      "smull r0, r1, r2\n"
+      "asr r3, r0, #31\n"
+      "cmp r3, r0 asr #63\n"
+      "bne +8\n"
+      "ret\n"
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(SmaddlOverflow3, assembler) {
@@ -2300,12 +3282,24 @@
 ASSEMBLER_TEST_RUN(SmaddlOverflow3, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x7fff\n"
+      "movk r1, #0x100 lsl 16\n"
+      "movz r2, #0x7fff\n"
+      "movk r2, #0x100 lsl 16\n"
+      "smull r0, r1, r2\n"
+      "asr r3, r0, #31\n"
+      "cmp r3, r0 asr #63\n"
+      "bne +8\n"
+      "ret\n"
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(NegNoOverflow, assembler) {
   Label return_ltuae;
   __ LoadImmediate(R1, 0x7fffffff);
-  __ negsw(R0, R1);  // X0 = W1*W2, alias of smaddl.
+  __ negsw(R0, R1);
   __ sxtw(R0, R0);
   __ b(&return_ltuae, VS);  // Branch on overflow set.
   __ ret();
@@ -2317,12 +3311,20 @@
 ASSEMBLER_TEST_RUN(NegNoOverflow, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-0x7fffffff, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r1, 0x7fffffff\n"
+      "negws r0, r1\n"
+      "sxtw r0, r0\n"
+      "bvs +8\n"
+      "ret\n"
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(NegNoOverflow2, assembler) {
   Label return_ltuae;
   __ LoadImmediate(R1, 0x7123);
-  __ negsw(R0, R1);  // X0 = W1*W2, alias of smaddl.
+  __ negsw(R0, R1);
   __ sxtw(R0, R0);
   __ b(&return_ltuae, VS);  // Branch on overflow set.
   __ ret();
@@ -2334,6 +3336,14 @@
 ASSEMBLER_TEST_RUN(NegNoOverflow2, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-0x7123, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x7123\n"
+      "negws r0, r1\n"
+      "sxtw r0, r0\n"
+      "bvs +8\n"
+      "ret\n"
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(NegOverflow, assembler) {
@@ -2351,6 +3361,14 @@
 ASSEMBLER_TEST_RUN(NegOverflow, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r1, 0xffffffff80000000\n"
+      "negws r0, r1\n"
+      "sxtw r0, r0\n"
+      "bvs +8\n"
+      "ret\n"
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 // Loading immediate values without the object pool.
@@ -2362,6 +3380,9 @@
 ASSEMBLER_TEST_RUN(LoadImmediateSmall, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadImmediateMed, assembler) {
@@ -2372,6 +3393,10 @@
 ASSEMBLER_TEST_RUN(LoadImmediateMed, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0xf1234123, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x4123\n"
+      "movk r0, #0xf123 lsl 16\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadImmediateMed2, assembler) {
@@ -2383,6 +3408,11 @@
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0x4321f1234123,
             EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x4123\n"
+      "movk r0, #0xf123 lsl 16\n"
+      "movk r0, #0x4321 lsl 32\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadImmediateLarge, assembler) {
@@ -2394,6 +3424,12 @@
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(static_cast<int64_t>(0x9287436598237465),
             EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x7465\n"
+      "movk r0, #0x9823 lsl 16\n"
+      "movk r0, #0x4365 lsl 32\n"
+      "movk r0, #0x9287 lsl 48\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadImmediateSmallNeg, assembler) {
@@ -2404,6 +3440,9 @@
 ASSEMBLER_TEST_RUN(LoadImmediateSmallNeg, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r0, #0x29\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadImmediateMedNeg, assembler) {
@@ -2414,6 +3453,11 @@
 ASSEMBLER_TEST_RUN(LoadImmediateMedNeg, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-0x1212341234, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r0, #0x12 lsl 32\n"
+      "movk r0, #0xedcb lsl 16\n"
+      "movk r0, #0xedcc\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadImmediateMedNeg2, assembler) {
@@ -2424,6 +3468,11 @@
 ASSEMBLER_TEST_RUN(LoadImmediateMedNeg2, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-0x1212340000, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r0, #0x12 lsl 32\n"
+      "movk r0, #0xedcc lsl 16\n"
+      "movk r0, #0x0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadImmediateMedNeg3, assembler) {
@@ -2434,6 +3483,10 @@
 ASSEMBLER_TEST_RUN(LoadImmediateMedNeg3, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-0x1200001234, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r0, #0x12 lsl 32\n"
+      "movk r0, #0xedcc\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadImmediateMedNeg4, assembler) {
@@ -2444,6 +3497,10 @@
 ASSEMBLER_TEST_RUN(LoadImmediateMedNeg4, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-0x12341234, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r0, #0x1234 lsl 16\n"
+      "movk r0, #0xedcc\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadHalfWordUnaligned, assembler) {
@@ -2467,6 +3524,10 @@
       static_cast<int16_t>(static_cast<uint16_t>(0xCDAB)),
       EXECUTE_TEST_CODE_INTPTR_INTPTR(LoadHalfWordUnaligned, test->entry(),
                                       reinterpret_cast<intptr_t>(&buffer[1])));
+  EXPECT_DISASSEMBLY(
+      "ldrsh r1, [r0]\n"
+      "mov r0, r1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadHalfWordUnsignedUnaligned, assembler) {
@@ -2488,6 +3549,10 @@
   EXPECT_EQ(0xCDAB, EXECUTE_TEST_CODE_INTPTR_INTPTR(
                         LoadHalfWordUnsignedUnaligned, test->entry(),
                         reinterpret_cast<intptr_t>(&buffer[1])));
+  EXPECT_DISASSEMBLY(
+      "ldrh r1, [r0]\n"
+      "mov r0, r1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(StoreHalfWordUnaligned, assembler) {
@@ -2517,6 +3582,11 @@
   EXPECT_EQ(0xCD, buffer[1]);
   EXPECT_EQ(0xAB, buffer[2]);
   EXPECT_EQ(0, buffer[3]);
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0xabcd\n"
+      "strh r1, [r0]\n"
+      "mov r0, r1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(LoadWordUnaligned, assembler) {
@@ -2546,6 +3616,10 @@
       static_cast<int32_t>(0xDEBC9A78),
       EXECUTE_TEST_CODE_INT32_INTPTR(LoadWordUnaligned, test->entry(),
                                      reinterpret_cast<intptr_t>(&buffer[3])));
+  EXPECT_DISASSEMBLY(
+      "ldrw r1, [r0]\n"
+      "mov r0, r1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(StoreWordUnaligned, assembler) {
@@ -2591,6 +3665,13 @@
   EXPECT_EQ(0x56, buffer[4]);
   EXPECT_EQ(0x34, buffer[5]);
   EXPECT_EQ(0x12, buffer[6]);
+
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x5678\n"
+      "movk r1, #0x1234 lsl 16\n"
+      "strw r1, [r0]\n"
+      "mov r0, r1\n"
+      "ret\n");
 }
 
 static void EnterTestFrame(Assembler* assembler) {
@@ -2758,6 +3839,12 @@
 ASSEMBLER_TEST_RUN(CSelTrue, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x2a\n"
+      "movz r2, #0x4d2\n"
+      "cmp r1, r2\n"
+      "csel r0, r1, r2, lt\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CSelFalse, assembler) {
@@ -2771,6 +3858,12 @@
 ASSEMBLER_TEST_RUN(CSelFalse, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(1234, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x2a\n"
+      "movz r2, #0x4d2\n"
+      "cmp r1, r2\n"
+      "csel r0, r1, r2, ge\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CsincFalse, assembler) {
@@ -2797,6 +3890,12 @@
 ASSEMBLER_TEST_RUN(CsincTrue, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(1234, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x2a\n"
+      "movz r2, #0x4d2\n"
+      "cmp r1, r2\n"
+      "cinc r0, r2, ge\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CsinvFalse, assembler) {
@@ -2810,6 +3909,12 @@
 ASSEMBLER_TEST_RUN(CsinvFalse, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(~42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x2a\n"
+      "movz r2, #0x4d2\n"
+      "cmp r1, r2\n"
+      "csinv r0, r2, r1, ge\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CsinvTrue, assembler) {
@@ -2823,6 +3928,12 @@
 ASSEMBLER_TEST_RUN(CsinvTrue, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(1234, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x2a\n"
+      "movz r2, #0x4d2\n"
+      "cmp r1, r2\n"
+      "csinv r0, r2, r1, lt\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CsnegFalse, assembler) {
@@ -2836,6 +3947,12 @@
 ASSEMBLER_TEST_RUN(CsnegFalse, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x2a\n"
+      "movz r2, #0x4d2\n"
+      "cmp r1, r2\n"
+      "csneg r0, r2, r1, ge\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CsnegTrue, assembler) {
@@ -2849,6 +3966,12 @@
 ASSEMBLER_TEST_RUN(CsnegTrue, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(1234, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x2a\n"
+      "movz r2, #0x4d2\n"
+      "cmp r1, r2\n"
+      "csneg r0, r2, r1, lt\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Ubfx, assembler) {
@@ -2861,6 +3984,12 @@
 ASSEMBLER_TEST_RUN(Ubfx, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0x81, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x819\n"
+      "movz r0, #0x5a5a\n"
+      "movk r0, #0x5a5a lsl 16\n"
+      "ubfm r0, r1, #4, #11\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Sbfx, assembler) {
@@ -2873,6 +4002,12 @@
 ASSEMBLER_TEST_RUN(Sbfx, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-0x7f, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x819\n"
+      "movz r0, #0x5a5a\n"
+      "movk r0, #0x5a5a lsl 16\n"
+      "sbfm r0, r1, #4, #11\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Bfi, assembler) {
@@ -2885,6 +4020,12 @@
 ASSEMBLER_TEST_RUN(Bfi, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0x5a5b9a5a, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x819\n"
+      "movz r0, #0x5a5a\n"
+      "movk r0, #0x5a5a lsl 16\n"
+      "bfm r0, r1, #52, #4\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Ubfiz, assembler) {
@@ -2898,6 +4039,13 @@
 ASSEMBLER_TEST_RUN(Ubfiz, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0x7e2491fe, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x48ff\n"
+      "movk r1, #0xff12 lsl 16\n"
+      "movz r0, #0x5a5a\n"
+      "movk r0, #0x5a5a lsl 16\n"
+      "ubfm r0, r1, #63, #29\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Bfxil, assembler) {
@@ -2910,6 +4058,12 @@
 ASSEMBLER_TEST_RUN(Bfxil, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0x5a5a5a81, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x819\n"
+      "movz r0, #0x5a5a\n"
+      "movk r0, #0x5a5a lsl 16\n"
+      "bfm r0, r1, #4, #11\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Sbfiz, assembler) {
@@ -2922,6 +4076,12 @@
 ASSEMBLER_TEST_RUN(Sbfiz, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-0x7e70, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0x819\n"
+      "movz r0, #0x5a5a\n"
+      "movk r0, #0x5a5a lsl 16\n"
+      "sbfm r0, r1, #60, #11\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Sxtb, assembler) {
@@ -2938,6 +4098,17 @@
 ASSEMBLER_TEST_RUN(Sxtb, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0x29, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r1, #0xff\n"
+      "movz r0, #0x5a5a\n"
+      "movk r0, #0x5a5a lsl 16\n"
+      "sxtb r0, r1\n"
+      "movz r2, #0x2a\n"
+      "movz r1, #0x5a5a\n"
+      "movk r1, #0x5a5a lsl 16\n"
+      "sxtb r1, r2\n"
+      "add r0, r0, r1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Sxth, assembler) {
@@ -2954,6 +4125,18 @@
 ASSEMBLER_TEST_RUN(Sxth, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0x29, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r1, 0xffff\n"
+      "movz r0, #0x5a5a\n"
+      "movk r0, #0x5a5a lsl 16\n"
+      "sxth r0, r1\n"
+      "movz r2, #0x2a\n"
+      "movk r2, #0x1 lsl 16\n"
+      "movz r1, #0x5a5a\n"
+      "movk r1, #0x5a5a lsl 16\n"
+      "sxth r1, r2\n"
+      "add r0, r0, r1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Sxtw, assembler) {
@@ -2970,6 +4153,18 @@
 ASSEMBLER_TEST_RUN(Sxtw, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0x29, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r1, 0xffffffff\n"
+      "movz r0, #0x5a5a\n"
+      "movk r0, #0x5a5a lsl 16\n"
+      "sxtw r0, r1\n"
+      "movz r2, #0x2a\n"
+      "movk r2, #0x1 lsl 32\n"
+      "movz r1, #0x5a5a\n"
+      "movk r1, #0x5a5a lsl 16\n"
+      "sxtw r1, r2\n"
+      "add r0, r0, r1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Uxtw, assembler) {
@@ -2987,6 +4182,18 @@
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0xffffffffll + 42,
             EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r1, 0xffffffff\n"
+      "movz r0, #0x5a5a\n"
+      "movk r0, #0x5a5a lsl 16\n"
+      "ubfm r0, r1, #0, #31\n"
+      "movz r2, #0x2a\n"
+      "movk r2, #0x1 lsl 32\n"
+      "movz r1, #0x5a5a\n"
+      "movk r1, #0x5a5a lsl 16\n"
+      "ubfm r1, r2, #0, #31\n"
+      "add r0, r0, r1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Uxtb, assembler) {
@@ -3003,6 +4210,17 @@
 ASSEMBLER_TEST_RUN(Uxtb, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0xff + 0x2a, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r1, #0x0\n"
+      "movz r0, #0x5a5a\n"
+      "movk r0, #0x5a5a lsl 16\n"
+      "uxtb r0, r1\n"
+      "movz r2, #0x12a\n"
+      "movz r1, #0x5a5a\n"
+      "movk r1, #0x5a5a lsl 16\n"
+      "uxtb r1, r2\n"
+      "add r0, r0, r1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Uxth, assembler) {
@@ -3019,6 +4237,18 @@
 ASSEMBLER_TEST_RUN(Uxth, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0xffff + 0x2a, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movn r1, #0x0\n"
+      "movz r0, #0x5a5a\n"
+      "movk r0, #0x5a5a lsl 16\n"
+      "uxth r0, r1\n"
+      "movz r2, #0x2a\n"
+      "movk r2, #0x1 lsl 16\n"
+      "movz r1, #0x5a5a\n"
+      "movk r1, #0x5a5a lsl 16\n"
+      "uxth r1, r2\n"
+      "add r0, r0, r1\n"
+      "ret\n");
 }
 
 // Floating point move immediate, to/from integer register.
@@ -3030,6 +4260,9 @@
 ASSEMBLER_TEST_RUN(Fmovdi, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(1.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "fmovd v0, 1.000000\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fmovdi2, assembler) {
@@ -3042,6 +4275,13 @@
   EXPECT_FLOAT_EQ(123412983.1324524315,
                   EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()),
                   0.0001f);
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0xa19c\n"
+      "movk ip0, #0xdc87 lsl 16\n"
+      "movk ip0, #0x6c87 lsl 32\n"
+      "movk ip0, #0x419d lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fmovrd, assembler) {
@@ -3054,6 +4294,10 @@
   typedef int64_t (*Int64Return)() DART_UNUSED;
   const int64_t one = bit_cast<int64_t, double>(1.0);
   EXPECT_EQ(one, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "fmovd v1, 1.000000\n"
+      "fmovrd r0, v1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fmovdr, assembler) {
@@ -3066,6 +4310,11 @@
 ASSEMBLER_TEST_RUN(Fmovdr, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(1.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "fmovd v1, 1.000000\n"
+      "fmovrd r1, v1\n"
+      "fmovdr v0, r1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fmovrs, assembler) {
@@ -3080,6 +4329,11 @@
   int64_t result = EXECUTE_TEST_CODE_INT64(Int64Return, test->entry());
   const uint32_t one = bit_cast<uint32_t, float>(1.0f);
   EXPECT_EQ(one, static_cast<uint32_t>(result));
+  EXPECT_DISASSEMBLY(
+      "fmovd v2, 1.000000\n"
+      "fcvtsd v1, v2\n"
+      "fmovrsw r0, v1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fmovsr, assembler) {
@@ -3094,6 +4348,11 @@
   int64_t result = EXECUTE_TEST_CODE_INT64(Int64Return, test->entry());
   const uint32_t one = bit_cast<uint32_t, float>(1.0f);
   EXPECT_EQ(one, static_cast<uint32_t>(result));
+  EXPECT_DISASSEMBLY(
+      "mov r2, 0x3f800000\n"
+      "fmovsrw v1, r2\n"
+      "fmovrsw r0, v1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FldrdFstrdPrePostIndex, assembler) {
@@ -3112,6 +4371,16 @@
 ASSEMBLER_TEST_RUN(FldrdFstrdPrePostIndex, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "sub csp, csp, #0x10\n"
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fstrd v1, [r15, #-8]!\n"
+      "fldrd v0, [r15], #8 !\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FldrsFstrsPrePostIndex, assembler) {
@@ -3132,6 +4401,18 @@
 ASSEMBLER_TEST_RUN(FldrsFstrsPrePostIndex, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "sub csp, csp, #0x10\n"
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fcvtsd v2, v1\n"
+      "fstrs v2, [r15, #-8]!\n"
+      "fldrs v3, [r15], #8 !\n"
+      "fcvtds v0, v3\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FldrqFstrqPrePostIndex, assembler) {
@@ -3159,6 +4440,24 @@
 ASSEMBLER_TEST_RUN(FldrqFstrqPrePostIndex, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "sub csp, csp, #0x10\n"
+      "fmovd v1, 21.000000\n"
+      "fmovd v2, 21.000000\n"
+      "movz r1, #0x2a\n"
+      "str r1, [r15, #-8]!\n"
+      "fstrd v1, [r15, #-8]!\n"
+      "fstrd v2, [r15, #-8]!\n"
+      "fldrq v3, [r15], #16 !\n"
+      "ldr r0, [r15], #8 !\n"
+      "fstrq v3, [r15, #-16]!\n"
+      "fldrd v0, [r15], #8 !\n"
+      "fldrd v1, [r15], #8 !\n"
+      "faddd v0, v0, v1\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtzsxd, assembler) {
@@ -3170,6 +4469,12 @@
 ASSEMBLER_TEST_RUN(Fcvtzsxd, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4000 lsl 32\n"
+      "movk ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtzs r0, v0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtzswd, assembler) {
@@ -3182,6 +4487,13 @@
 ASSEMBLER_TEST_RUN(Fcvtzswd, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4000 lsl 32\n"
+      "movk ip0, #0xc045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtzsw r0, v0\n"
+      "sxtw r0, r0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtzsxd_overflow, assembler) {
@@ -3204,6 +4516,14 @@
 ASSEMBLER_TEST_RUN(Fcvtzsxd_overflow_negative, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(kMinInt64, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x8c40\n"
+      "movk ip0, #0x78b5 lsl 16\n"
+      "movk ip0, #0xaf1d lsl 32\n"
+      "movk ip0, #0xc415 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtzs r0, v0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtzswd_overflow, assembler) {
@@ -3215,6 +4535,13 @@
 ASSEMBLER_TEST_RUN(Fcvtzswd_overflow, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(kMaxInt32, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x2000 lsl 16\n"
+      "movk ip0, #0xa05f lsl 32\n"
+      "movk ip0, #0x4202 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtzsw r0, v0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtzswd_overflow_negative, assembler) {
@@ -3227,6 +4554,14 @@
 ASSEMBLER_TEST_RUN(Fcvtzswd_overflow_negative, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(kMinInt32, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x2000 lsl 16\n"
+      "movk ip0, #0xa05f lsl 32\n"
+      "movk ip0, #0xc202 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtzsw r0, v0\n"
+      "sxtw r0, r0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtpsxd, assembler) {
@@ -3238,6 +4573,12 @@
 ASSEMBLER_TEST_RUN(Fcvtpsxd, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(43, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4000 lsl 32\n"
+      "movk ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtps r0, v0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtpswd, assembler) {
@@ -3250,6 +4591,13 @@
 ASSEMBLER_TEST_RUN(Fcvtpswd, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4000 lsl 32\n"
+      "movk ip0, #0xc045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtpsw r0, v0\n"
+      "sxtw r0, r0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtpsxd_overflow, assembler) {
@@ -3261,6 +4609,14 @@
 ASSEMBLER_TEST_RUN(Fcvtpsxd_overflow, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(kMaxInt64, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x8c40\n"
+      "movk ip0, #0x78b5 lsl 16\n"
+      "movk ip0, #0xaf1d lsl 32\n"
+      "movk ip0, #0x4415 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtps r0, v0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtpsxd_overflow_negative, assembler) {
@@ -3272,6 +4628,14 @@
 ASSEMBLER_TEST_RUN(Fcvtpsxd_overflow_negative, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(kMinInt64, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x8c40\n"
+      "movk ip0, #0x78b5 lsl 16\n"
+      "movk ip0, #0xaf1d lsl 32\n"
+      "movk ip0, #0xc415 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtps r0, v0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtpswd_overflow, assembler) {
@@ -3283,6 +4647,13 @@
 ASSEMBLER_TEST_RUN(Fcvtpswd_overflow, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(kMaxInt32, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x2000 lsl 16\n"
+      "movk ip0, #0xa05f lsl 32\n"
+      "movk ip0, #0x4202 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtpsw r0, v0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtpswd_overflow_negative, assembler) {
@@ -3295,6 +4666,14 @@
 ASSEMBLER_TEST_RUN(Fcvtpswd_overflow_negative, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(kMinInt32, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x2000 lsl 16\n"
+      "movk ip0, #0xa05f lsl 32\n"
+      "movk ip0, #0xc202 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtpsw r0, v0\n"
+      "sxtw r0, r0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtmsxd, assembler) {
@@ -3306,6 +4685,12 @@
 ASSEMBLER_TEST_RUN(Fcvtmsxd, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4000 lsl 32\n"
+      "movk ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtms r0, v0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtmswd, assembler) {
@@ -3318,6 +4703,13 @@
 ASSEMBLER_TEST_RUN(Fcvtmswd, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-43, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4000 lsl 32\n"
+      "movk ip0, #0xc045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtmsw r0, v0\n"
+      "sxtw r0, r0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtmsxd_overflow, assembler) {
@@ -3329,6 +4721,14 @@
 ASSEMBLER_TEST_RUN(Fcvtmsxd_overflow, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(kMaxInt64, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x8c40\n"
+      "movk ip0, #0x78b5 lsl 16\n"
+      "movk ip0, #0xaf1d lsl 32\n"
+      "movk ip0, #0x4415 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtms r0, v0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtmsxd_overflow_negative, assembler) {
@@ -3340,6 +4740,14 @@
 ASSEMBLER_TEST_RUN(Fcvtmsxd_overflow_negative, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(kMinInt64, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x8c40\n"
+      "movk ip0, #0x78b5 lsl 16\n"
+      "movk ip0, #0xaf1d lsl 32\n"
+      "movk ip0, #0xc415 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtms r0, v0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtmswd_overflow, assembler) {
@@ -3351,6 +4759,13 @@
 ASSEMBLER_TEST_RUN(Fcvtmswd_overflow, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(kMaxInt32, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x2000 lsl 16\n"
+      "movk ip0, #0xa05f lsl 32\n"
+      "movk ip0, #0x4202 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtmsw r0, v0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fcvtmswd_overflow_negative, assembler) {
@@ -3363,6 +4778,14 @@
 ASSEMBLER_TEST_RUN(Fcvtmswd_overflow_negative, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(kMinInt32, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x2000 lsl 16\n"
+      "movk ip0, #0xa05f lsl 32\n"
+      "movk ip0, #0xc202 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtmsw r0, v0\n"
+      "sxtw r0, r0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Scvtfdx, assembler) {
@@ -3374,6 +4797,10 @@
 ASSEMBLER_TEST_RUN(Scvtfdx, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "scvtfd v0, r0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Scvtfdw, assembler) {
@@ -3386,6 +4813,12 @@
 ASSEMBLER_TEST_RUN(Scvtfdw, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "movk r0, #0x1111 lsl 32\n"
+      "movk r0, #0x1111 lsl 48\n"
+      "scvtfdw v0, r0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FabsdPos, assembler) {
@@ -3397,6 +4830,11 @@
 ASSEMBLER_TEST_RUN(FabsdPos, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fabsd v0, v1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FabsdNeg, assembler) {
@@ -3408,6 +4846,11 @@
 ASSEMBLER_TEST_RUN(FabsdNeg, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0xc045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fabsd v0, v1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FnegdPos, assembler) {
@@ -3419,6 +4862,11 @@
 ASSEMBLER_TEST_RUN(FnegdPos, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(-42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fnegd v0, v1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FnegdNeg, assembler) {
@@ -3430,6 +4878,11 @@
 ASSEMBLER_TEST_RUN(FnegdNeg, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0xc045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fnegd v0, v1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fsqrtd, assembler) {
@@ -3441,6 +4894,11 @@
 ASSEMBLER_TEST_RUN(Fsqrtd, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(8.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4050 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fsqrtd v0, v1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fmuld, assembler) {
@@ -3453,6 +4911,12 @@
 ASSEMBLER_TEST_RUN(Fmuld, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4055 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fmovd v2, 0.500000\n"
+      "fmuld v0, v1, v2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fdivd, assembler) {
@@ -3465,6 +4929,12 @@
 ASSEMBLER_TEST_RUN(Fdivd, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4055 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fmovd v2, 2.000000\n"
+      "fdivd v0, v1, v2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Faddd, assembler) {
@@ -3477,6 +4947,13 @@
 ASSEMBLER_TEST_RUN(Faddd, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0xc000 lsl 32\n"
+      "movk ip0, #0x4044 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fmovd v2, 0.500000\n"
+      "faddd v0, v1, v2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Fsubd, assembler) {
@@ -3489,6 +4966,13 @@
 ASSEMBLER_TEST_RUN(Fsubd, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4000 lsl 32\n"
+      "movk ip0, #0x4045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fmovd v2, 0.500000\n"
+      "fsubd v0, v1, v2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FldrdFstrdHeapTag, assembler) {
@@ -3507,6 +4991,21 @@
 ASSEMBLER_TEST_RUN(FldrdFstrdHeapTag, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz ip0, #0x8000 lsl 32\n"
+      "movk ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "sub r15, r15, #0x8\n"
+      "add r2, r15, #0x1\n"
+      "fstrd v1, [r2, #-1]\n"
+      "fldrd v0, [r2, #-1]\n"
+      "add r15, r15, #0x8\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FldrdFstrdLargeIndex, assembler) {
@@ -3530,6 +5029,20 @@
 ASSEMBLER_TEST_RUN(FldrdFstrdLargeIndex, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "sub csp, csp, #0x100\n"
+      "movz ip0, #0x8000 lsl 32\n"
+      "movk ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fstrd v1, [r15, #-256]!\n"
+      "fldrd v0, [r15], #248 !\n"
+      "add r15, r15, #0x8\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FldrdFstrdLargeOffset, assembler) {
@@ -3548,6 +5061,21 @@
 ASSEMBLER_TEST_RUN(FldrdFstrdLargeOffset, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz ip0, #0x8000 lsl 32\n"
+      "movk ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "sub r15, r15, #0x1000\n"
+      "and csp, r15, 0xfffffffffffffff0\n"
+      "fstrd v1, [r15, #4096]\n"
+      "add r15, r15, #0x1000\n"
+      "fldrd v0, [r15]\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FldrdFstrdExtReg, assembler) {
@@ -3570,6 +5098,23 @@
 ASSEMBLER_TEST_RUN(FldrdFstrdExtReg, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz ip0, #0x8000 lsl 32\n"
+      "movk ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "movz r2, #0xfff8\n"
+      "movk r2, #0xffff lsl 16\n"
+      "fstrd v1, [r15, r2 sxtw]\n"
+      "sub r15, r15, #0x8\n"
+      "and csp, r15, 0xfffffffffffffff0\n"
+      "fldrd v0, [r15]\n"
+      "add r15, r15, #0x8\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(FldrdFstrdScaledReg, assembler) {
@@ -3590,6 +5135,22 @@
 ASSEMBLER_TEST_RUN(FldrdFstrdScaledReg, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz ip0, #0x8000 lsl 32\n"
+      "movk ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "movz r2, #0xa\n"
+      "sub r15, r15, #0x50\n"
+      "and csp, r15, 0xfffffffffffffff0\n"
+      "fstrd v1, [r15, r2 uxtx scaled]\n"
+      "fldrd v0, [r15, r2 uxtx scaled]\n"
+      "add r15, r15, #0x50\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(VinswVmovrs, assembler) {
@@ -3618,6 +5179,23 @@
   EXPECT(test != NULL);
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(174, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "movz r1, #0x2b\n"
+      "movz r2, #0x2c\n"
+      "movz r3, #0x2d\n"
+      "vinss v0[0], r0\n"
+      "vinss v0[1], r1\n"
+      "vinss v0[2], r2\n"
+      "vinss v0[3], r3\n"
+      "vmovrs r4, v0[0]\n"
+      "vmovrs r5, v0[1]\n"
+      "vmovrs r6, v0[2]\n"
+      "vmovrs r7, v0[3]\n"
+      "add r0, r4, r5\n"
+      "add r0, r0, r6\n"
+      "add r0, r0, r7\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(VinsxVmovrd, assembler) {
@@ -3638,6 +5216,15 @@
   EXPECT(test != NULL);
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(85, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r0, #0x2a\n"
+      "movz r1, #0x2b\n"
+      "vinsd v0[0], r0\n"
+      "vinsd v0[1], r1\n"
+      "vmovrd r2, v0[0]\n"
+      "vmovrd r3, v0[1]\n"
+      "add r0, r2, r3\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vnot, assembler) {
@@ -3664,6 +5251,22 @@
   EXPECT(test != NULL);
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(2, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r0, 0xfffffffe\n"
+      "mov r1, 0xffffffff\n"
+      "vinss v1[0], r1\n"
+      "vinss v1[1], r0\n"
+      "vinss v1[2], r1\n"
+      "vinss v1[3], r0\n"
+      "vnot v0, v1\n"
+      "vmovrs r2, v0[0]\n"
+      "vmovrs r3, v0[1]\n"
+      "vmovrs r4, v0[2]\n"
+      "vmovrs r5, v0[3]\n"
+      "add r0, r2, r3\n"
+      "add r0, r0, r4\n"
+      "add r0, r0, r5\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vabss, assembler) {
@@ -3692,6 +5295,21 @@
 ASSEMBLER_TEST_RUN(Vabss, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "fmovd v1, 21.000000\n"
+      "fmovd v2, -21.000000\n"
+      "fcvtsd v1, v1\n"
+      "fcvtsd v2, v2\n"
+      "veor v3, v3, v3\n"
+      "vinss v3[1], v1[0]\n"
+      "vinss v3[3], v2[0]\n"
+      "vabss v4, v3\n"
+      "vinss v5[0], v4[1]\n"
+      "vinss v6[0], v4[3]\n"
+      "fcvtds v5, v5\n"
+      "fcvtds v6, v6\n"
+      "faddd v0, v5, v6\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vabsd, assembler) {
@@ -3713,6 +5331,16 @@
 ASSEMBLER_TEST_RUN(Vabsd, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "fmovd v1, 21.000000\n"
+      "fmovd v2, -21.000000\n"
+      "vinsd v3[0], v1[0]\n"
+      "vinsd v3[1], v2[0]\n"
+      "vabsd v4, v3\n"
+      "vinsd v5[0], v4[0]\n"
+      "vinsd v6[0], v4[1]\n"
+      "faddd v0, v5, v6\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vnegs, assembler) {
@@ -3740,6 +5368,23 @@
 ASSEMBLER_TEST_RUN(Vnegs, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "movz ip0, #0xc055 lsl 48\n"
+      "fmovdr v2, ip0\n"
+      "fcvtsd v1, v1\n"
+      "fcvtsd v2, v2\n"
+      "veor v3, v3, v3\n"
+      "vinss v3[1], v1[0]\n"
+      "vinss v3[3], v2[0]\n"
+      "vnegs v4, v3\n"
+      "vinss v5[0], v4[1]\n"
+      "vinss v6[0], v4[3]\n"
+      "fcvtds v5, v5\n"
+      "fcvtds v6, v6\n"
+      "faddd v0, v5, v6\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vnegd, assembler) {
@@ -3761,6 +5406,19 @@
 ASSEMBLER_TEST_RUN(Vnegd, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      ""
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "movz ip0, #0xc055 lsl 48\n"
+      "fmovdr v2, ip0\n"
+      "vinsd v3[0], v1[0]\n"
+      "vinsd v3[1], v2[0]\n"
+      "vnegd v4, v3\n"
+      "vinsd v5[0], v4[0]\n"
+      "vinsd v6[0], v4[1]\n"
+      "faddd v0, v5, v6\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vadds, assembler) {
@@ -3800,6 +5458,33 @@
 ASSEMBLER_TEST_RUN(Vadds, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(12.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x0\n"
+      "fmovdr v0, ip0\n"
+      "fmovd v1, 1.000000\n"
+      "fmovd v2, 2.000000\n"
+      "fmovd v3, 3.000000\n"
+      "fcvtsd v0, v0\n"
+      "fcvtsd v1, v1\n"
+      "fcvtsd v2, v2\n"
+      "fcvtsd v3, v3\n"
+      "vinss v4[0], v0[0]\n"
+      "vinss v4[1], v1[0]\n"
+      "vinss v4[2], v2[0]\n"
+      "vinss v4[3], v3[0]\n"
+      "vadds v5, v4, v4\n"
+      "vinss v0[0], v5[0]\n"
+      "vinss v1[0], v5[1]\n"
+      "vinss v2[0], v5[2]\n"
+      "vinss v3[0], v5[3]\n"
+      "fcvtds v0, v0\n"
+      "fcvtds v1, v1\n"
+      "fcvtds v2, v2\n"
+      "fcvtds v3, v3\n"
+      "faddd v0, v0, v1\n"
+      "faddd v0, v0, v2\n"
+      "faddd v0, v0, v3\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vsubs, assembler) {
@@ -3840,6 +5525,36 @@
 ASSEMBLER_TEST_RUN(Vsubs, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(-6.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      ""
+      "movz ip0, #0x0\n"
+      "fmovdr v0, ip0\n"
+      "fmovd v1, 1.000000\n"
+      "fmovd v2, 2.000000\n"
+      "fmovd v3, 3.000000\n"
+      "movz ip0, #0x0\n"
+      "fmovdr v5, ip0\n"
+      "fcvtsd v0, v0\n"
+      "fcvtsd v1, v1\n"
+      "fcvtsd v2, v2\n"
+      "fcvtsd v3, v3\n"
+      "vinss v4[0], v0[0]\n"
+      "vinss v4[1], v1[0]\n"
+      "vinss v4[2], v2[0]\n"
+      "vinss v4[3], v3[0]\n"
+      "vsubs v5, v5, v4\n"
+      "vinss v0[0], v5[0]\n"
+      "vinss v1[0], v5[1]\n"
+      "vinss v2[0], v5[2]\n"
+      "vinss v3[0], v5[3]\n"
+      "fcvtds v0, v0\n"
+      "fcvtds v1, v1\n"
+      "fcvtds v2, v2\n"
+      "fcvtds v3, v3\n"
+      "faddd v0, v0, v1\n"
+      "faddd v0, v0, v2\n"
+      "faddd v0, v0, v3\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vmuls, assembler) {
@@ -3879,6 +5594,34 @@
 ASSEMBLER_TEST_RUN(Vmuls, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(14.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      ""
+      "movz ip0, #0x0\n"
+      "fmovdr v0, ip0\n"
+      "fmovd v1, 1.000000\n"
+      "fmovd v2, 2.000000\n"
+      "fmovd v3, 3.000000\n"
+      "fcvtsd v0, v0\n"
+      "fcvtsd v1, v1\n"
+      "fcvtsd v2, v2\n"
+      "fcvtsd v3, v3\n"
+      "vinss v4[0], v0[0]\n"
+      "vinss v4[1], v1[0]\n"
+      "vinss v4[2], v2[0]\n"
+      "vinss v4[3], v3[0]\n"
+      "vmuls v5, v4, v4\n"
+      "vinss v0[0], v5[0]\n"
+      "vinss v1[0], v5[1]\n"
+      "vinss v2[0], v5[2]\n"
+      "vinss v3[0], v5[3]\n"
+      "fcvtds v0, v0\n"
+      "fcvtds v1, v1\n"
+      "fcvtds v2, v2\n"
+      "fcvtds v3, v3\n"
+      "faddd v0, v0, v1\n"
+      "faddd v0, v0, v2\n"
+      "faddd v0, v0, v3\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vdivs, assembler) {
@@ -3918,6 +5661,34 @@
 ASSEMBLER_TEST_RUN(Vdivs, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(4.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      ""
+      "movz ip0, #0x0\n"
+      "fmovdr v0, ip0\n"
+      "fmovd v1, 1.000000\n"
+      "fmovd v2, 2.000000\n"
+      "fmovd v3, 3.000000\n"
+      "fcvtsd v0, v0\n"
+      "fcvtsd v1, v1\n"
+      "fcvtsd v2, v2\n"
+      "fcvtsd v3, v3\n"
+      "vinss v4[0], v0[0]\n"
+      "vinss v4[1], v1[0]\n"
+      "vinss v4[2], v2[0]\n"
+      "vinss v4[3], v3[0]\n"
+      "vdivs v5, v4, v4\n"
+      "vinss v0[0], v5[0]\n"
+      "vinss v1[0], v5[1]\n"
+      "vinss v2[0], v5[2]\n"
+      "vinss v3[0], v5[3]\n"
+      "fcvtds v0, v0\n"
+      "fcvtds v1, v1\n"
+      "fcvtds v2, v2\n"
+      "fcvtds v3, v3\n"
+      "faddd v0, v1, v1\n"
+      "faddd v0, v0, v2\n"
+      "faddd v0, v0, v3\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vaddd, assembler) {
@@ -3939,6 +5710,17 @@
 ASSEMBLER_TEST_RUN(Vaddd, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(10.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      ""
+      "fmovd v0, 2.000000\n"
+      "fmovd v1, 3.000000\n"
+      "vinsd v4[0], v0[0]\n"
+      "vinsd v4[1], v1[0]\n"
+      "vaddd v5, v4, v4\n"
+      "vinsd v0[0], v5[0]\n"
+      "vinsd v1[0], v5[1]\n"
+      "faddd v0, v0, v1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vsubd, assembler) {
@@ -3961,6 +5743,18 @@
 ASSEMBLER_TEST_RUN(Vsubd, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(-5.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "fmovd v0, 2.000000\n"
+      "fmovd v1, 3.000000\n"
+      "movz ip0, #0x0\n"
+      "fmovdr v5, ip0\n"
+      "vinsd v4[0], v0[0]\n"
+      "vinsd v4[1], v1[0]\n"
+      "vsubd v5, v5, v4\n"
+      "vinsd v0[0], v5[0]\n"
+      "vinsd v1[0], v5[1]\n"
+      "faddd v0, v0, v1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vmuld, assembler) {
@@ -3982,6 +5776,17 @@
 ASSEMBLER_TEST_RUN(Vmuld, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(13.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      ""
+      "fmovd v0, 2.000000\n"
+      "fmovd v1, 3.000000\n"
+      "vinsd v4[0], v0[0]\n"
+      "vinsd v4[1], v1[0]\n"
+      "vmuld v5, v4, v4\n"
+      "vinsd v0[0], v5[0]\n"
+      "vinsd v1[0], v5[1]\n"
+      "faddd v0, v0, v1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vdivd, assembler) {
@@ -4003,6 +5808,16 @@
 ASSEMBLER_TEST_RUN(Vdivd, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(2.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "fmovd v0, 2.000000\n"
+      "fmovd v1, 3.000000\n"
+      "vinsd v4[0], v0[0]\n"
+      "vinsd v4[1], v1[0]\n"
+      "vdivd v5, v4, v4\n"
+      "vinsd v0[0], v5[0]\n"
+      "vinsd v1[0], v5[1]\n"
+      "faddd v0, v0, v1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vdupd, assembler) {
@@ -4028,6 +5843,19 @@
 ASSEMBLER_TEST_RUN(Vdupd, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      ""
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "fmovd v0, 21.000000\n"
+      "vdupd v1, v0[0]\n"
+      "sub csp, csp, #0x10\n"
+      "fstrq v1, [r15, #-16]!\n"
+      "fldrd v2, [r15], #8 !\n"
+      "fldrd v3, [r15], #8 !\n"
+      "faddd v0, v2, v3\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vdups, assembler) {
@@ -4063,6 +5891,28 @@
 ASSEMBLER_TEST_RUN(Vdups, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(84.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      ""
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "fmovd v0, 21.000000\n"
+      "fcvtsd v0, v0\n"
+      "vdups v1, v0[0]\n"
+      "sub csp, csp, #0x10\n"
+      "fstrq v1, [r15, #-16]!\n"
+      "fldrs v3, [r15], #4 !\n"
+      "fldrs v2, [r15], #4 !\n"
+      "fldrs v1, [r15], #4 !\n"
+      "fldrs v0, [r15], #4 !\n"
+      "fcvtds v0, v0\n"
+      "fcvtds v1, v1\n"
+      "fcvtds v2, v2\n"
+      "fcvtds v3, v3\n"
+      "faddd v0, v1, v1\n"
+      "faddd v0, v0, v2\n"
+      "faddd v0, v0, v3\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vinsd, assembler) {
@@ -4088,6 +5938,20 @@
 ASSEMBLER_TEST_RUN(Vinsd, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      ""
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v5, ip0\n"
+      "vinsd v1[1], v5[0]\n"
+      "sub csp, csp, #0x10\n"
+      "fstrq v1, [r15, #-16]!\n"
+      "fldrd v2, [r15], #8 !\n"
+      "fldrd v3, [r15], #8 !\n"
+      "fmovdd v0, v3\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vinss, assembler) {
@@ -4131,6 +5995,33 @@
 ASSEMBLER_TEST_RUN(Vinss, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "fmovd v0, 21.000000\n"
+      "fcvtsd v0, v0\n"
+      "vinss v1[3], v0[0]\n"
+      "vinss v1[1], v0[0]\n"
+      "movz ip0, #0x0\n"
+      "fmovdr v0, ip0\n"
+      "fcvtsd v0, v0\n"
+      "vinss v1[2], v0[0]\n"
+      "vinss v1[0], v0[0]\n"
+      "sub csp, csp, #0x10\n"
+      "fstrq v1, [r15, #-16]!\n"
+      "fldrs v3, [r15], #4 !\n"
+      "fldrs v2, [r15], #4 !\n"
+      "fldrs v1, [r15], #4 !\n"
+      "fldrs v0, [r15], #4 !\n"
+      "fcvtds v0, v0\n"
+      "fcvtds v1, v1\n"
+      "fcvtds v2, v2\n"
+      "fcvtds v3, v3\n"
+      "faddd v0, v0, v1\n"
+      "faddd v0, v0, v2\n"
+      "faddd v0, v0, v3\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vand, assembler) {
@@ -4166,6 +6057,26 @@
 ASSEMBLER_TEST_RUN(Vand, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "fmovd v1, 21.000000\n"
+      "mov r0, 0xffffffff\n"
+      "fmovdr v0, r0\n"
+      "vinss v0[2], v0[0]\n"
+      "fcvtsd v1, v1\n"
+      "vdups v1, v1[0]\n"
+      "vand v2, v1, v0\n"
+      "vinss v3[0], v2[0]\n"
+      "vinss v4[0], v2[1]\n"
+      "vinss v5[0], v2[2]\n"
+      "vinss v6[0], v2[3]\n"
+      "fcvtds v3, v3\n"
+      "fcvtds v4, v4\n"
+      "fcvtds v5, v5\n"
+      "fcvtds v6, v6\n"
+      "vaddd v0, v3, v4\n"
+      "vaddd v0, v0, v5\n"
+      "vaddd v0, v0, v6\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vorr, assembler) {
@@ -4202,6 +6113,27 @@
 ASSEMBLER_TEST_RUN(Vorr, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "fmovd v1, 10.500000\n"
+      "fcvtsd v1, v1\n"
+      "fmovdd v0, v1\n"
+      "vinss v0[2], v0[0]\n"
+      "veor v1, v1, v1\n"
+      "vinss v1[1], v0[0]\n"
+      "vinss v1[3], v0[0]\n"
+      "vorr v2, v1, v0\n"
+      "vinss v3[0], v2[0]\n"
+      "vinss v4[0], v2[1]\n"
+      "vinss v5[0], v2[2]\n"
+      "vinss v6[0], v2[3]\n"
+      "fcvtds v3, v3\n"
+      "fcvtds v4, v4\n"
+      "fcvtds v5, v5\n"
+      "fcvtds v6, v6\n"
+      "vaddd v0, v3, v4\n"
+      "vaddd v0, v0, v5\n"
+      "vaddd v0, v0, v6\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Veor, assembler) {
@@ -4234,6 +6166,26 @@
 ASSEMBLER_TEST_RUN(Veor, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "mov r1, 0xffffffff\n"
+      "movn r2, #0x15\n"
+      "vinss v1[0], r1\n"
+      "vinss v1[1], r2\n"
+      "vinss v1[2], r1\n"
+      "vinss v1[3], r2\n"
+      "vinss v2[0], r1\n"
+      "vinss v2[1], r1\n"
+      "vinss v2[2], r1\n"
+      "vinss v2[3], r1\n"
+      "veor v0, v1, v2\n"
+      "vmovrs r3, v0[0]\n"
+      "vmovrs r4, v0[1]\n"
+      "vmovrs r5, v0[2]\n"
+      "vmovrs r6, v0[3]\n"
+      "add r0, r3, r4\n"
+      "add r0, r0, r5\n"
+      "add r0, r0, r6\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vaddw, assembler) {
@@ -4257,6 +6209,19 @@
 ASSEMBLER_TEST_RUN(Vaddw, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(168, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r4, #0x15\n"
+      "vdups v1, r4\n"
+      "vdups v2, r4\n"
+      "vaddw v0, v1, v2\n"
+      "vmovrs r0, v0[0]\n"
+      "vmovrs r1, v0[1]\n"
+      "vmovrs r2, v0[2]\n"
+      "vmovrs r3, v0[3]\n"
+      "add r0, r0, r1\n"
+      "add r0, r0, r2\n"
+      "add r0, r0, r3\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vsubw, assembler) {
@@ -4281,6 +6246,20 @@
 ASSEMBLER_TEST_RUN(Vsubw, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(84, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r4, #0x1f\n"
+      "movz r5, #0xa\n"
+      "vdups v1, r4\n"
+      "vdups v2, r5\n"
+      "vsubw v0, v1, v2\n"
+      "vmovrs r0, v0[0]\n"
+      "vmovrs r1, v0[1]\n"
+      "vmovrs r2, v0[2]\n"
+      "vmovrs r3, v0[3]\n"
+      "add r0, r0, r1\n"
+      "add r0, r0, r2\n"
+      "add r0, r0, r3\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vaddx, assembler) {
@@ -4300,6 +6279,15 @@
 ASSEMBLER_TEST_RUN(Vaddx, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(84, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r4, #0x15\n"
+      "vdupd v1, r4\n"
+      "vdupd v2, r4\n"
+      "vaddx v0, v1, v2\n"
+      "vmovrd r0, v0[0]\n"
+      "vmovrd r1, v0[1]\n"
+      "add r0, r0, r1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vsubx, assembler) {
@@ -4320,6 +6308,16 @@
 ASSEMBLER_TEST_RUN(Vsubx, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(42, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz r4, #0x1f\n"
+      "movz r5, #0xa\n"
+      "vdupd v1, r4\n"
+      "vdupd v2, r5\n"
+      "vsubx v0, v1, v2\n"
+      "vmovrd r0, v0[0]\n"
+      "vmovrd r1, v0[1]\n"
+      "add r0, r0, r1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vceqs, assembler) {
@@ -4351,6 +6349,27 @@
 ASSEMBLER_TEST_RUN(Vceqs, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0xfffffffe, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0xc045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fcvtsd v0, v0\n"
+      "fcvtsd v1, v1\n"
+      "vdups v2, v0[0]\n"
+      "vinss v3[0], v0[0]\n"
+      "vinss v3[1], v1[0]\n"
+      "vinss v3[2], v0[0]\n"
+      "vinss v3[3], v1[0]\n"
+      "vceqs v4, v2, v3\n"
+      "vmovrs r1, v4[0]\n"
+      "vmovrs r2, v4[1]\n"
+      "vmovrs r3, v4[2]\n"
+      "vmovrs r4, v4[3]\n"
+      "addw r0, r1, r2\n"
+      "addw r0, r0, r3\n"
+      "addw r0, r0, r4\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vceqd, assembler) {
@@ -4373,6 +6392,19 @@
 ASSEMBLER_TEST_RUN(Vceqd, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-1, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0xc045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "vdupd v2, v0[0]\n"
+      "vinsd v3[0], v0[0]\n"
+      "vinsd v3[1], v1[0]\n"
+      "vceqd v4, v2, v3\n"
+      "vmovrd r1, v4[0]\n"
+      "vmovrd r2, v4[1]\n"
+      "add r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vcgts, assembler) {
@@ -4404,6 +6436,27 @@
 ASSEMBLER_TEST_RUN(Vcgts, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0xfffffffe, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0xc045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fcvtsd v0, v0\n"
+      "fcvtsd v1, v1\n"
+      "vdups v2, v0[0]\n"
+      "vinss v3[0], v0[0]\n"
+      "vinss v3[1], v1[0]\n"
+      "vinss v3[2], v0[0]\n"
+      "vinss v3[3], v1[0]\n"
+      "vcgts v4, v2, v3\n"
+      "vmovrs r1, v4[0]\n"
+      "vmovrs r2, v4[1]\n"
+      "vmovrs r3, v4[2]\n"
+      "vmovrs r4, v4[3]\n"
+      "addw r0, r1, r2\n"
+      "addw r0, r0, r3\n"
+      "addw r0, r0, r4\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vcgtd, assembler) {
@@ -4426,6 +6479,19 @@
 ASSEMBLER_TEST_RUN(Vcgtd, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-1, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0xc045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "vdupd v2, v0[0]\n"
+      "vinsd v3[0], v0[0]\n"
+      "vinsd v3[1], v1[0]\n"
+      "vcgtd v4, v2, v3\n"
+      "vmovrd r1, v4[0]\n"
+      "vmovrd r2, v4[1]\n"
+      "add r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vcges, assembler) {
@@ -4457,6 +6523,28 @@
 ASSEMBLER_TEST_RUN(Vcges, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(0xfffffffe, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0x8000 lsl 32\n"
+      "movk ip0, #0x4045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fcvtsd v0, v0\n"
+      "fcvtsd v1, v1\n"
+      "vdups v2, v0[0]\n"
+      "vinss v3[0], v0[0]\n"
+      "vinss v3[1], v1[0]\n"
+      "vinss v3[2], v0[0]\n"
+      "vinss v3[3], v1[0]\n"
+      "vcges v4, v2, v3\n"
+      "vmovrs r1, v4[0]\n"
+      "vmovrs r2, v4[1]\n"
+      "vmovrs r3, v4[2]\n"
+      "vmovrs r4, v4[3]\n"
+      "addw r0, r1, r2\n"
+      "addw r0, r0, r3\n"
+      "addw r0, r0, r4\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vcged, assembler) {
@@ -4479,6 +6567,20 @@
 ASSEMBLER_TEST_RUN(Vcged, test) {
   typedef int64_t (*Int64Return)() DART_UNUSED;
   EXPECT_EQ(-1, EXECUTE_TEST_CODE_INT64(Int64Return, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4045 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0x8000 lsl 32\n"
+      "movk ip0, #0x4045 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "vdupd v2, v0[0]\n"
+      "vinsd v3[0], v0[0]\n"
+      "vinsd v3[1], v1[0]\n"
+      "vcged v4, v2, v3\n"
+      "vmovrd r1, v4[0]\n"
+      "vmovrd r2, v4[1]\n"
+      "add r0, r1, r2\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vmaxs, assembler) {
@@ -4515,6 +6617,29 @@
 ASSEMBLER_TEST_RUN(Vmaxs, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "fmovd v0, 10.500000\n"
+      "fmovd v1, 10.000000\n"
+      "fcvtsd v0, v0\n"
+      "fcvtsd v1, v1\n"
+      "vdups v2, v0[0]\n"
+      "vinss v3[0], v0[0]\n"
+      "vinss v3[1], v1[0]\n"
+      "vinss v3[2], v0[0]\n"
+      "vinss v3[3], v1[0]\n"
+      "vmaxs v4, v2, v3\n"
+      "vinss v0[0], v4[0]\n"
+      "vinss v1[0], v4[1]\n"
+      "vinss v2[0], v4[2]\n"
+      "vinss v3[0], v4[3]\n"
+      "fcvtds v0, v0\n"
+      "fcvtds v1, v1\n"
+      "fcvtds v2, v2\n"
+      "fcvtds v3, v3\n"
+      "faddd v0, v0, v1\n"
+      "faddd v0, v0, v2\n"
+      "faddd v0, v0, v3\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vmaxd, assembler) {
@@ -4537,6 +6662,19 @@
 ASSEMBLER_TEST_RUN(Vmaxd, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "fmovd v0, 21.000000\n"
+      "movz ip0, #0x8000 lsl 32\n"
+      "movk ip0, #0x4034 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "vdupd v2, v0[0]\n"
+      "vinsd v3[0], v0[0]\n"
+      "vinsd v3[1], v1[0]\n"
+      "vmaxd v4, v2, v3\n"
+      "vinsd v0[0], v4[0]\n"
+      "vinsd v1[0], v4[1]\n"
+      "faddd v0, v0, v1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vmins, assembler) {
@@ -4573,6 +6711,29 @@
 ASSEMBLER_TEST_RUN(Vmins, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "fmovd v0, 10.500000\n"
+      "fmovd v1, 11.000000\n"
+      "fcvtsd v0, v0\n"
+      "fcvtsd v1, v1\n"
+      "vdups v2, v0[0]\n"
+      "vinss v3[0], v0[0]\n"
+      "vinss v3[1], v1[0]\n"
+      "vinss v3[2], v0[0]\n"
+      "vinss v3[3], v1[0]\n"
+      "vmins v4, v2, v3\n"
+      "vinss v0[0], v4[0]\n"
+      "vinss v1[0], v4[1]\n"
+      "vinss v2[0], v4[2]\n"
+      "vinss v3[0], v4[3]\n"
+      "fcvtds v0, v0\n"
+      "fcvtds v1, v1\n"
+      "fcvtds v2, v2\n"
+      "fcvtds v3, v3\n"
+      "faddd v0, v0, v1\n"
+      "faddd v0, v0, v2\n"
+      "faddd v0, v0, v3\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vmind, assembler) {
@@ -4595,6 +6756,19 @@
 ASSEMBLER_TEST_RUN(Vmind, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(42.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "fmovd v0, 21.000000\n"
+      "movz ip0, #0x8000 lsl 32\n"
+      "movk ip0, #0x4035 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "vdupd v2, v0[0]\n"
+      "vinsd v3[0], v0[0]\n"
+      "vinsd v3[1], v1[0]\n"
+      "vmind v4, v2, v3\n"
+      "vinsd v0[0], v4[0]\n"
+      "vinsd v1[0], v4[1]\n"
+      "faddd v0, v0, v1\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vsqrts, assembler) {
@@ -4623,6 +6797,24 @@
 ASSEMBLER_TEST_RUN(Vsqrts, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(15.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4050 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0x8000 lsl 32\n"
+      "movk ip0, #0x4048 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fcvtsd v0, v0\n"
+      "fcvtsd v1, v1\n"
+      "veor v3, v3, v3\n"
+      "vinss v3[1], v0[0]\n"
+      "vinss v3[3], v1[0]\n"
+      "vsqrts v4, v3\n"
+      "vinss v5[0], v4[1]\n"
+      "vinss v6[0], v4[3]\n"
+      "fcvtds v5, v5\n"
+      "fcvtds v6, v6\n"
+      "faddd v0, v5, v6\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vsqrtd, assembler) {
@@ -4644,6 +6836,19 @@
 ASSEMBLER_TEST_RUN(Vsqrtd, test) {
   typedef double (*DoubleReturn)() DART_UNUSED;
   EXPECT_EQ(15.0, EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry()));
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x4050 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "movz ip0, #0x8000 lsl 32\n"
+      "movk ip0, #0x4048 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "vinsd v3[0], v0[0]\n"
+      "vinsd v3[1], v1[0]\n"
+      "vsqrtd v4, v3\n"
+      "vinsd v5[0], v4[0]\n"
+      "vinsd v6[0], v4[1]\n"
+      "faddd v0, v5, v6\n"
+      "ret\n");
 }
 
 // This is the same function as in the Simulator.
@@ -4700,6 +6905,18 @@
   typedef double (*DoubleReturn)() DART_UNUSED;
   float res = EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry());
   EXPECT_FLOAT_EQ(arm_recip_estimate(147.0), res, 0.0001);
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x6000 lsl 32\n"
+      "movk ip0, #0x4062 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fcvtsd v1, v1\n"
+      "vinss v2[0], v1[0]\n"
+      "vinss v2[1], v1[0]\n"
+      "vinss v2[2], v1[0]\n"
+      "vinss v2[3], v1[0]\n"
+      "vrecpes v0, v2\n"
+      "fcvtds v0, v0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vrecpss, assembler) {
@@ -4720,6 +6937,14 @@
   typedef double (*DoubleReturn)() DART_UNUSED;
   double res = EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry());
   EXPECT_FLOAT_EQ(2.0 - 10.0 * 5.0, res, 0.0001);
+  EXPECT_DISASSEMBLY(
+      "fmovd v1, 5.000000\n"
+      "fmovd v2, 10.000000\n"
+      "fcvtsd v1, v1\n"
+      "fcvtsd v2, v2\n"
+      "vrecpss v0, v1, v2\n"
+      "fcvtds v0, v0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(VRecps, assembler) {
@@ -4750,6 +6975,31 @@
   typedef double (*DoubleReturn)() DART_UNUSED;
   double res = EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry());
   EXPECT_FLOAT_EQ(42.0, res, 0.0001);
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x8618\n"
+      "movk ip0, #0x1861 lsl 16\n"
+      "movk ip0, #0x6186 lsl 32\n"
+      "movk ip0, #0x3fb8 lsl 48\n"
+      "fmovdr v0, ip0\n"
+      "fcvtsd v0, v0\n"
+      "vdups v1, v0[0]\n"
+      "vrecpes v2, v1\n"
+      "vrecpss v31, v1, v2\n"
+      "vmuls v2, v2, v31\n"
+      "vrecpss v31, v1, v2\n"
+      "vmuls v2, v2, v31\n"
+      "vinss v0[0], v2[0]\n"
+      "vinss v1[0], v2[1]\n"
+      "vinss v2[0], v2[2]\n"
+      "vinss v3[0], v2[3]\n"
+      "fcvtds v0, v0\n"
+      "fcvtds v1, v1\n"
+      "fcvtds v2, v2\n"
+      "fcvtds v3, v3\n"
+      "faddd v0, v0, v1\n"
+      "faddd v0, v0, v2\n"
+      "faddd v0, v0, v3\n"
+      "ret\n");
 }
 
 static float arm_reciprocal_sqrt_estimate(float a) {
@@ -4821,6 +7071,14 @@
   typedef double (*DoubleReturn)() DART_UNUSED;
   double res = EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry());
   EXPECT_FLOAT_EQ(arm_reciprocal_sqrt_estimate(147.0), res, 0.0001);
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0x6000 lsl 32\n"
+      "movk ip0, #0x4062 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fcvtsd v1, v1\n"
+      "vrsqrtes v0, v1\n"
+      "fcvtds v0, v0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(Vrsqrtss, assembler) {
@@ -4841,6 +7099,14 @@
   typedef double (*DoubleReturn)() DART_UNUSED;
   double res = EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry());
   EXPECT_FLOAT_EQ((3.0 - 10.0 * 5.0) / 2.0, res, 0.0001);
+  EXPECT_DISASSEMBLY(
+      "fmovd v1, 5.000000\n"
+      "fmovd v2, 10.000000\n"
+      "fcvtsd v1, v1\n"
+      "fcvtsd v2, v2\n"
+      "vrsqrts v0, v1, v2\n"
+      "fcvtds v0, v0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(ReciprocalSqrt, assembler) {
@@ -4858,6 +7124,20 @@
   typedef double (*DoubleReturn)() DART_UNUSED;
   double res = EXECUTE_TEST_CODE_DOUBLE(DoubleReturn, test->entry());
   EXPECT_FLOAT_EQ(1.0 / sqrt(147000.0), res, 0.0001);
+  EXPECT_DISASSEMBLY(
+      "movz ip0, #0xf1c0 lsl 32\n"
+      "movk ip0, #0x4101 lsl 48\n"
+      "fmovdr v1, ip0\n"
+      "fcvtsd v1, v1\n"
+      "vrsqrtes v0, v1\n"
+      "vmuls v31, v0, v0\n"
+      "vrsqrts v31, v1, v31\n"
+      "vmuls v0, v0, v31\n"
+      "vmuls v31, v0, v0\n"
+      "vrsqrts v31, v1, v31\n"
+      "vmuls v0, v0, v31\n"
+      "fcvtds v0, v0\n"
+      "ret\n");
 }
 
 // Called from assembler_test.cc.
@@ -4919,6 +7199,9 @@
   EXPECT_EQ(0, EXECUTE_TEST_CODE_INTPTR_INTPTR(IntPtrReturn, test->entry(), 0));
   EXPECT_EQ(0,
             EXECUTE_TEST_CODE_INTPTR_INTPTR(IntPtrReturn, test->entry(), 42));
+  EXPECT_DISASSEMBLY(
+      "andw r0, r0, 0xfffffe00\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(OrImmediate32Negative, assembler) {
@@ -4934,6 +7217,9 @@
             EXECUTE_TEST_CODE_INTPTR_INTPTR(IntPtrReturn, test->entry(), 0));
   EXPECT_EQ(0xfffffe2a,
             EXECUTE_TEST_CODE_INTPTR_INTPTR(IntPtrReturn, test->entry(), 42));
+  EXPECT_DISASSEMBLY(
+      "orrw r0, r0, 0xfffffe00\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(XorImmediate32Negative, assembler) {
@@ -4949,6 +7235,9 @@
             EXECUTE_TEST_CODE_INTPTR_INTPTR(IntPtrReturn, test->entry(), 0));
   EXPECT_EQ(0xfffffe2a,
             EXECUTE_TEST_CODE_INTPTR_INTPTR(IntPtrReturn, test->entry(), 42));
+  EXPECT_DISASSEMBLY(
+      "eorw r0, r0, 0xfffffe00\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(TestImmediate32Negative, assembler) {
@@ -4969,6 +7258,13 @@
   EXPECT_EQ(0, EXECUTE_TEST_CODE_INTPTR_INTPTR(IntPtrReturn, test->entry(), 0));
   EXPECT_EQ(0,
             EXECUTE_TEST_CODE_INTPTR_INTPTR(IntPtrReturn, test->entry(), 42));
+  EXPECT_DISASSEMBLY(
+      "tstw r0, 0xfffffe00\n"
+      "beq +12\n"
+      "movz r0, #0x1\n"
+      "ret\n"
+      "movz r0, #0x0\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(CompareImmediate32Negative, assembler) {
@@ -4990,6 +7286,13 @@
             EXECUTE_TEST_CODE_INTPTR_INTPTR(IntPtrReturn, test->entry(), -512));
   EXPECT_EQ(0,
             EXECUTE_TEST_CODE_INTPTR_INTPTR(IntPtrReturn, test->entry(), -511));
+  EXPECT_DISASSEMBLY(
+      "cmnw r0, #0x200\n"
+      "blt +12\n"
+      "movz r0, #0x0\n"
+      "ret\n"
+      "movz r0, #0x1\n"
+      "ret\n");
 }
 
 #if !defined(USING_THREAD_SANITIZER)
@@ -5014,6 +7317,20 @@
   typedef intptr_t (*StoreReleaseLoadAcquire)(intptr_t) DART_UNUSED;
   EXPECT_EQ(123, EXECUTE_TEST_CODE_INTPTR_INTPTR(StoreReleaseLoadAcquire,
                                                  test->entry(), 123));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "str r1, [r15, #-8]!\n"
+      "movz r1, #0x0\n"
+      "str r1, [r15, #-8]!\n"
+      "mov r1, r0\n"
+      "movz r0, #0x0\n"
+      "stlr r1, r15\n"
+      "ldar r0, r15\n"
+      "ldr r1, [r15], #8 !\n"
+      "ldr r1, [r15], #8 !\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 
 ASSEMBLER_TEST_GENERATE(StoreReleaseLoadAcquire1024, assembler) {
@@ -5037,6 +7354,24 @@
   typedef intptr_t (*StoreReleaseLoadAcquire1024)(intptr_t) DART_UNUSED;
   EXPECT_EQ(123, EXECUTE_TEST_CODE_INTPTR_INTPTR(StoreReleaseLoadAcquire1024,
                                                  test->entry(), 123));
+  EXPECT_DISASSEMBLY(
+      "mov r15, csp\n"
+      "sub csp, csp, #0x1000\n"
+      "str r1, [r15, #-8]!\n"
+      "movz r1, #0x0\n"
+      "str r1, [r15, #-8]!\n"
+      "mov r1, r0\n"
+      "movz r0, #0x0\n"
+      "sub r15, r15, #0x2000\n"
+      "add ip0, r15, #0x400\n"
+      "stlr r1, ip0\n"
+      "add ip1, r15, #0x400\n"
+      "ldar r0, ip1\n"
+      "add r15, r15, #0x2000\n"
+      "ldr r1, [r15], #8 !\n"
+      "ldr r1, [r15], #8 !\n"
+      "mov csp, r15\n"
+      "ret\n");
 }
 #endif
 
diff --git a/runtime/vm/compiler/assembler/assembler_arm_test.cc b/runtime/vm/compiler/assembler/assembler_arm_test.cc
index f925d7c..64db0ae 100644
--- a/runtime/vm/compiler/assembler/assembler_arm_test.cc
+++ b/runtime/vm/compiler/assembler/assembler_arm_test.cc
@@ -273,81 +273,68 @@
 }
 
 ASSEMBLER_TEST_GENERATE(Vmov, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ mov(R3, Operand(43));
-    __ mov(R1, Operand(41));
-    __ vmovsrr(S1, R1, R3);       // S1:S2 = 41:43
-    __ vmovs(S0, S2);             // S0 = S2, S0:S1 == 43:41
-    __ vmovd(D2, D0);             // D2 = D0, S4:S5 == 43:41
-    __ vmovrs(R3, S5);            // R3 = S5, R3 == 41
-    __ vmovrrs(R1, R2, S4);       // R1:R2 = S4:S5, R1:R2 == 43:41
-    __ vmovdrr(D3, R3, R2);       // D3 = R3:R2, S6:S7 == 41:41
-    __ vmovdr(D3, 1, R1);         // D3[1] == S7 = R1, S6:S7 == 41:43
-    __ vmovrrd(R0, R1, D3);       // R0:R1 = D3, R0:R1 == 41:43
-    __ sub(R0, R1, Operand(R0));  // 43-41
-  }
+  __ mov(R3, Operand(43));
+  __ mov(R1, Operand(41));
+  __ vmovsrr(S1, R1, R3);       // S1:S2 = 41:43
+  __ vmovs(S0, S2);             // S0 = S2, S0:S1 == 43:41
+  __ vmovd(D2, D0);             // D2 = D0, S4:S5 == 43:41
+  __ vmovrs(R3, S5);            // R3 = S5, R3 == 41
+  __ vmovrrs(R1, R2, S4);       // R1:R2 = S4:S5, R1:R2 == 43:41
+  __ vmovdrr(D3, R3, R2);       // D3 = R3:R2, S6:S7 == 41:41
+  __ vmovdr(D3, 1, R1);         // D3[1] == S7 = R1, S6:S7 == 41:43
+  __ vmovrrd(R0, R1, D3);       // R0:R1 = D3, R0:R1 == 41:43
+  __ sub(R0, R1, Operand(R0));  // 43-41
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(Vmov, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef int (*Vmov)() DART_UNUSED;
-    EXPECT_EQ(2, EXECUTE_TEST_CODE_INT32(Vmov, test->entry()));
-  }
+  typedef int (*Vmov)() DART_UNUSED;
+  EXPECT_EQ(2, EXECUTE_TEST_CODE_INT32(Vmov, test->entry()));
 }
 
 ASSEMBLER_TEST_GENERATE(SingleVLoadStore, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ LoadImmediate(R0, bit_cast<int32_t, float>(12.3f));
-    __ mov(R2, Operand(SP));
-    __ str(R0, Address(SP, (-target::kWordSize * 30), Address::PreIndex));
-    __ vldrs(S0, Address(R2, (-target::kWordSize * 30)));
-    __ vadds(S0, S0, S0);
-    __ vstrs(S0, Address(R2, (-target::kWordSize * 30)));
-    __ ldr(R0, Address(SP, (target::kWordSize * 30), Address::PostIndex));
-  }
+  __ LoadImmediate(R0, bit_cast<int32_t, float>(12.3f));
+  __ mov(R2, Operand(SP));
+  __ str(R0, Address(SP, (-target::kWordSize * 30), Address::PreIndex));
+  __ vldrs(S0, Address(R2, (-target::kWordSize * 30)));
+  __ vadds(S0, S0, S0);
+  __ vstrs(S0, Address(R2, (-target::kWordSize * 30)));
+  __ ldr(R0, Address(SP, (target::kWordSize * 30), Address::PostIndex));
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(SingleVLoadStore, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef float (*SingleVLoadStore)() DART_UNUSED;
-    float res = EXECUTE_TEST_CODE_FLOAT(SingleVLoadStore, test->entry());
-    EXPECT_FLOAT_EQ(2 * 12.3f, res, 0.001f);
-  }
+  typedef float (*SingleVLoadStore)() DART_UNUSED;
+  float res = EXECUTE_TEST_CODE_FLOAT(SingleVLoadStore, test->entry());
+  EXPECT_FLOAT_EQ(2 * 12.3f, res, 0.001f);
 }
 
 ASSEMBLER_TEST_GENERATE(SingleVShiftLoadStore, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ LoadImmediate(R0, bit_cast<int32_t, float>(12.3f));
-    __ mov(R2, Operand(SP));
-    // Expressing __str(R0, Address(SP, (-kWordSize * 32), Address::PreIndex));
-    // as:
-    __ mov(R1, Operand(target::kWordSize));
-    __ str(R0, Address(SP, R1, LSL, 5, Address::NegPreIndex));
-    __ vldrs(S0, Address(R2, (-target::kWordSize * 32)));
-    __ vadds(S0, S0, S0);
-    __ vstrs(S0, Address(R2, (-target::kWordSize * 32)));
-    // Expressing __ldr(R0, Address(SP, (kWordSize * 32), Address::PostIndex));
-    // as:
-    __ ldr(R0, Address(SP, R1, LSL, 5, Address::PostIndex));
-  }
+  __ LoadImmediate(R0, bit_cast<int32_t, float>(12.3f));
+  __ mov(R2, Operand(SP));
+  // Expressing __str(R0, Address(SP, (-kWordSize * 32), Address::PreIndex));
+  // as:
+  __ mov(R1, Operand(target::kWordSize));
+  __ str(R0, Address(SP, R1, LSL, 5, Address::NegPreIndex));
+  __ vldrs(S0, Address(R2, (-target::kWordSize * 32)));
+  __ vadds(S0, S0, S0);
+  __ vstrs(S0, Address(R2, (-target::kWordSize * 32)));
+  // Expressing __ldr(R0, Address(SP, (kWordSize * 32), Address::PostIndex));
+  // as:
+  __ ldr(R0, Address(SP, R1, LSL, 5, Address::PostIndex));
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(SingleVShiftLoadStore, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef float (*SingleVLoadStore)() DART_UNUSED;
-    float res = EXECUTE_TEST_CODE_FLOAT(SingleVLoadStore, test->entry());
-    EXPECT_FLOAT_EQ(2 * 12.3f, res, 0.001f);
-  }
+  typedef float (*SingleVLoadStore)() DART_UNUSED;
+  float res = EXECUTE_TEST_CODE_FLOAT(SingleVLoadStore, test->entry());
+  EXPECT_FLOAT_EQ(2 * 12.3f, res, 0.001f);
 }
 
 ASSEMBLER_TEST_GENERATE(DoubleVLoadStore, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
     int64_t value = bit_cast<int64_t, double>(12.3);
     __ LoadImmediate(R0, Utils::Low32Bits(value));
     __ LoadImmediate(R1, Utils::High32Bits(value));
@@ -359,69 +346,57 @@
     __ vstrd(D0, Address(R2, (-target::kWordSize * 30)));
     __ ldr(R1, Address(R2, (-target::kWordSize * 29)));
     __ ldr(R0, Address(SP, (target::kWordSize * 30), Address::PostIndex));
-  }
-  __ Ret();
+    __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(DoubleVLoadStore, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef double (*DoubleVLoadStore)() DART_UNUSED;
-    float res = EXECUTE_TEST_CODE_DOUBLE(DoubleVLoadStore, test->entry());
-    EXPECT_FLOAT_EQ(2 * 12.3f, res, 0.001f);
-  }
+  typedef double (*DoubleVLoadStore)() DART_UNUSED;
+  float res = EXECUTE_TEST_CODE_DOUBLE(DoubleVLoadStore, test->entry());
+  EXPECT_FLOAT_EQ(2 * 12.3f, res, 0.001f);
 }
 
 ASSEMBLER_TEST_GENERATE(SingleFPOperations, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ LoadSImmediate(S0, 12.3f);
-    __ LoadSImmediate(S1, 3.4f);
-    __ vnegs(S0, S0);      // -12.3f
-    __ vabss(S0, S0);      // 12.3f
-    __ vadds(S0, S0, S1);  // 15.7f
-    __ vmuls(S0, S0, S1);  // 53.38f
-    __ vsubs(S0, S0, S1);  // 49.98f
-    __ vdivs(S0, S0, S1);  // 14.7f
-    __ vsqrts(S0, S0);     // 3.8340579f
-  }
+  __ LoadSImmediate(S0, 12.3f);
+  __ LoadSImmediate(S1, 3.4f);
+  __ vnegs(S0, S0);      // -12.3f
+  __ vabss(S0, S0);      // 12.3f
+  __ vadds(S0, S0, S1);  // 15.7f
+  __ vmuls(S0, S0, S1);  // 53.38f
+  __ vsubs(S0, S0, S1);  // 49.98f
+  __ vdivs(S0, S0, S1);  // 14.7f
+  __ vsqrts(S0, S0);     // 3.8340579f
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(SingleFPOperations, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef float (*SingleFPOperations)() DART_UNUSED;
-    float res = EXECUTE_TEST_CODE_FLOAT(SingleFPOperations, test->entry());
-    EXPECT_FLOAT_EQ(3.8340579f, res, 0.001f);
-  }
+  typedef float (*SingleFPOperations)() DART_UNUSED;
+  float res = EXECUTE_TEST_CODE_FLOAT(SingleFPOperations, test->entry());
+  EXPECT_FLOAT_EQ(3.8340579f, res, 0.001f);
 }
 
 ASSEMBLER_TEST_GENERATE(DoubleFPOperations, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ LoadDImmediate(D0, 12.3, R0);
-    __ LoadDImmediate(D1, 3.4, R0);
-    __ vnegd(D0, D0);      // -12.3
-    __ vabsd(D0, D0);      // 12.3
-    __ vaddd(D0, D0, D1);  // 15.7
-    __ vmuld(D0, D0, D1);  // 53.38
-    __ vsubd(D0, D0, D1);  // 49.98
-    __ vdivd(D0, D0, D1);  // 14.7
-    __ vsqrtd(D0, D0);     // 3.8340579
-  }
+  __ LoadDImmediate(D0, 12.3, R0);
+  __ LoadDImmediate(D1, 3.4, R0);
+  __ vnegd(D0, D0);      // -12.3
+  __ vabsd(D0, D0);      // 12.3
+  __ vaddd(D0, D0, D1);  // 15.7
+  __ vmuld(D0, D0, D1);  // 53.38
+  __ vsubd(D0, D0, D1);  // 49.98
+  __ vdivd(D0, D0, D1);  // 14.7
+  __ vsqrtd(D0, D0);     // 3.8340579
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(DoubleFPOperations, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef double (*DoubleFPOperations)() DART_UNUSED;
-    double res = EXECUTE_TEST_CODE_DOUBLE(DoubleFPOperations, test->entry());
-    EXPECT_FLOAT_EQ(3.8340579, res, 0.001);
-  }
+  typedef double (*DoubleFPOperations)() DART_UNUSED;
+  double res = EXECUTE_TEST_CODE_DOUBLE(DoubleFPOperations, test->entry());
+  EXPECT_FLOAT_EQ(3.8340579, res, 0.001);
 }
 
 ASSEMBLER_TEST_GENERATE(DoubleSqrtNeg, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
     // Check that sqrt of a negative double gives NaN.
     __ LoadDImmediate(D1, -1.0, R0);
     __ vsqrtd(D0, D1);
@@ -429,161 +404,128 @@
     __ vmstat();
     __ mov(R0, Operand(1), VS);
     __ mov(R0, Operand(0), VC);
-  }
-  __ Ret();
+    __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(DoubleSqrtNeg, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef int (*DoubleSqrtNeg)() DART_UNUSED;
-    EXPECT_EQ(1, EXECUTE_TEST_CODE_INT32(DoubleSqrtNeg, test->entry()));
-  }
+  typedef int (*DoubleSqrtNeg)() DART_UNUSED;
+  EXPECT_EQ(1, EXECUTE_TEST_CODE_INT32(DoubleSqrtNeg, test->entry()));
 }
 
 ASSEMBLER_TEST_GENERATE(IntToDoubleConversion, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ mov(R3, Operand(6));
-    __ vmovsr(S3, R3);
-    __ vcvtdi(D0, S3);
-  }
+  __ mov(R3, Operand(6));
+  __ vmovsr(S3, R3);
+  __ vcvtdi(D0, S3);
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(IntToDoubleConversion, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef double (*IntToDoubleConversionCode)() DART_UNUSED;
-    double res =
-        EXECUTE_TEST_CODE_DOUBLE(IntToDoubleConversionCode, test->entry());
-    EXPECT_FLOAT_EQ(6.0, res, 0.001);
-  }
+  typedef double (*IntToDoubleConversionCode)() DART_UNUSED;
+  double res =
+      EXECUTE_TEST_CODE_DOUBLE(IntToDoubleConversionCode, test->entry());
+  EXPECT_FLOAT_EQ(6.0, res, 0.001);
 }
 
 ASSEMBLER_TEST_GENERATE(LongToDoubleConversion, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    int64_t value = 60000000000LL;
-    __ LoadImmediate(R0, Utils::Low32Bits(value));
-    __ LoadImmediate(R1, Utils::High32Bits(value));
-    __ vmovsr(S0, R0);
-    __ vmovsr(S2, R1);
-    __ vcvtdu(D0, S0);
-    __ vcvtdi(D1, S2);
-    __ LoadDImmediate(D2, 1.0 * (1LL << 32), R0);
-    __ vmlad(D0, D1, D2);
-  }
+  int64_t value = 60000000000LL;
+  __ LoadImmediate(R0, Utils::Low32Bits(value));
+  __ LoadImmediate(R1, Utils::High32Bits(value));
+  __ vmovsr(S0, R0);
+  __ vmovsr(S2, R1);
+  __ vcvtdu(D0, S0);
+  __ vcvtdi(D1, S2);
+  __ LoadDImmediate(D2, 1.0 * (1LL << 32), R0);
+  __ vmlad(D0, D1, D2);
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(LongToDoubleConversion, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef double (*LongToDoubleConversionCode)() DART_UNUSED;
-    double res =
-        EXECUTE_TEST_CODE_DOUBLE(LongToDoubleConversionCode, test->entry());
-    EXPECT_FLOAT_EQ(60000000000.0, res, 0.001);
-  }
+  typedef double (*LongToDoubleConversionCode)() DART_UNUSED;
+  double res =
+      EXECUTE_TEST_CODE_DOUBLE(LongToDoubleConversionCode, test->entry());
+  EXPECT_FLOAT_EQ(60000000000.0, res, 0.001);
 }
 
 ASSEMBLER_TEST_GENERATE(IntToFloatConversion, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ mov(R3, Operand(6));
-    __ vmovsr(S3, R3);
-    __ vcvtsi(S0, S3);
-  }
+  __ mov(R3, Operand(6));
+  __ vmovsr(S3, R3);
+  __ vcvtsi(S0, S3);
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(IntToFloatConversion, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef float (*IntToFloatConversionCode)() DART_UNUSED;
-    float res =
-        EXECUTE_TEST_CODE_FLOAT(IntToFloatConversionCode, test->entry());
-    EXPECT_FLOAT_EQ(6.0, res, 0.001);
-  }
+  typedef float (*IntToFloatConversionCode)() DART_UNUSED;
+  float res = EXECUTE_TEST_CODE_FLOAT(IntToFloatConversionCode, test->entry());
+  EXPECT_FLOAT_EQ(6.0, res, 0.001);
 }
 
 ASSEMBLER_TEST_GENERATE(FloatToIntConversion, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ vcvtis(S1, S0);
-    __ vmovrs(R0, S1);
-  }
+  __ vcvtis(S1, S0);
+  __ vmovrs(R0, S1);
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(FloatToIntConversion, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef int (*FloatToIntConversion)(float arg) DART_UNUSED;
-    EXPECT_EQ(12, EXECUTE_TEST_CODE_INT32_F(FloatToIntConversion, test->entry(),
-                                            12.8f));
-    EXPECT_EQ(INT32_MIN, EXECUTE_TEST_CODE_INT32_F(FloatToIntConversion,
-                                                   test->entry(), -FLT_MAX));
-    EXPECT_EQ(INT32_MAX, EXECUTE_TEST_CODE_INT32_F(FloatToIntConversion,
-                                                   test->entry(), FLT_MAX));
-  }
+  typedef int (*FloatToIntConversion)(float arg) DART_UNUSED;
+  EXPECT_EQ(12, EXECUTE_TEST_CODE_INT32_F(FloatToIntConversion, test->entry(),
+                                          12.8f));
+  EXPECT_EQ(INT32_MIN, EXECUTE_TEST_CODE_INT32_F(FloatToIntConversion,
+                                                 test->entry(), -FLT_MAX));
+  EXPECT_EQ(INT32_MAX, EXECUTE_TEST_CODE_INT32_F(FloatToIntConversion,
+                                                 test->entry(), FLT_MAX));
 }
 
 ASSEMBLER_TEST_GENERATE(DoubleToIntConversion, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ vcvtid(S0, D0);
-    __ vmovrs(R0, S0);
-  }
+  __ vcvtid(S0, D0);
+  __ vmovrs(R0, S0);
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(DoubleToIntConversion, test) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef int (*DoubleToIntConversion)(double arg) DART_UNUSED;
-    EXPECT(test != NULL);
-    EXPECT_EQ(12, EXECUTE_TEST_CODE_INT32_D(DoubleToIntConversion,
-                                            test->entry(), 12.8));
-    EXPECT_EQ(INT32_MIN, EXECUTE_TEST_CODE_INT32_D(DoubleToIntConversion,
-                                                   test->entry(), -DBL_MAX));
-    EXPECT_EQ(INT32_MAX, EXECUTE_TEST_CODE_INT32_D(DoubleToIntConversion,
-                                                   test->entry(), DBL_MAX));
-  }
+  typedef int (*DoubleToIntConversion)(double arg) DART_UNUSED;
+  EXPECT(test != NULL);
+  EXPECT_EQ(12, EXECUTE_TEST_CODE_INT32_D(DoubleToIntConversion, test->entry(),
+                                          12.8));
+  EXPECT_EQ(INT32_MIN, EXECUTE_TEST_CODE_INT32_D(DoubleToIntConversion,
+                                                 test->entry(), -DBL_MAX));
+  EXPECT_EQ(INT32_MAX, EXECUTE_TEST_CODE_INT32_D(DoubleToIntConversion,
+                                                 test->entry(), DBL_MAX));
 }
 
 ASSEMBLER_TEST_GENERATE(FloatToDoubleConversion, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ LoadSImmediate(S2, 12.8f);
-    __ vcvtds(D0, S2);
-  }
+  __ LoadSImmediate(S2, 12.8f);
+  __ vcvtds(D0, S2);
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(FloatToDoubleConversion, test) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef double (*FloatToDoubleConversionCode)() DART_UNUSED;
-    EXPECT(test != NULL);
-    double res =
-        EXECUTE_TEST_CODE_DOUBLE(FloatToDoubleConversionCode, test->entry());
-    EXPECT_FLOAT_EQ(12.8, res, 0.001);
-  }
+  typedef double (*FloatToDoubleConversionCode)() DART_UNUSED;
+  EXPECT(test != NULL);
+  double res =
+      EXECUTE_TEST_CODE_DOUBLE(FloatToDoubleConversionCode, test->entry());
+  EXPECT_FLOAT_EQ(12.8, res, 0.001);
 }
 
 ASSEMBLER_TEST_GENERATE(DoubleToFloatConversion, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ LoadDImmediate(D1, 12.8, R0);
-    __ vcvtsd(S0, D1);
-  }
+  __ LoadDImmediate(D1, 12.8, R0);
+  __ vcvtsd(S0, D1);
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(DoubleToFloatConversion, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef float (*DoubleToFloatConversionCode)() DART_UNUSED;
-    float res =
-        EXECUTE_TEST_CODE_FLOAT(DoubleToFloatConversionCode, test->entry());
-    EXPECT_FLOAT_EQ(12.8, res, 0.001);
-  }
+  typedef float (*DoubleToFloatConversionCode)() DART_UNUSED;
+  float res =
+      EXECUTE_TEST_CODE_FLOAT(DoubleToFloatConversionCode, test->entry());
+  EXPECT_FLOAT_EQ(12.8, res, 0.001);
 }
 
 ASSEMBLER_TEST_GENERATE(FloatCompare, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
     // Test 12.3f vs 12.5f.
     __ LoadSImmediate(S0, 12.3f);
     __ LoadSImmediate(S1, 12.5f);
@@ -605,21 +547,17 @@
     __ vmstat();
     // Error if not unordered (not Nan).
     __ add(R0, R0, Operand(16), VC);
-  }
-  // R0 is 0 if all tests passed.
-  __ Ret();
+    // R0 is 0 if all tests passed.
+    __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(FloatCompare, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef int (*FloatCompare)() DART_UNUSED;
-    EXPECT_EQ(0, EXECUTE_TEST_CODE_INT32(FloatCompare, test->entry()));
-  }
+  typedef int (*FloatCompare)() DART_UNUSED;
+  EXPECT_EQ(0, EXECUTE_TEST_CODE_INT32(FloatCompare, test->entry()));
 }
 
 ASSEMBLER_TEST_GENERATE(DoubleCompare, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
     // Test 12.3 vs 12.5.
     __ LoadDImmediate(D0, 12.3, R1);
     __ LoadDImmediate(D1, 12.5, R1);
@@ -641,17 +579,14 @@
     __ vmstat();
     // Error if not unordered (not Nan).
     __ add(R0, R0, Operand(16), VC);
-  }
-  // R0 is 0 if all tests passed.
-  __ Ret();
+    // R0 is 0 if all tests passed.
+    __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(DoubleCompare, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef int (*DoubleCompare)() DART_UNUSED;
-    EXPECT_EQ(0, EXECUTE_TEST_CODE_INT32(DoubleCompare, test->entry()));
-  }
+  typedef int (*DoubleCompare)() DART_UNUSED;
+  EXPECT_EQ(0, EXECUTE_TEST_CODE_INT32(DoubleCompare, test->entry()));
 }
 
 ASSEMBLER_TEST_GENERATE(Loop, assembler) {
@@ -976,28 +911,24 @@
 }
 
 ASSEMBLER_TEST_GENERATE(QuotientRemainder, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ vmovsr(S2, R0);
-    __ vmovsr(S4, R2);
-    __ vcvtdi(D1, S2);
-    __ vcvtdi(D2, S4);
-    __ vdivd(D0, D1, D2);
-    __ vcvtid(S0, D0);
-    __ vmovrs(R1, S0);       // r1 = r0/r2
-    __ mls(R0, R1, R2, R0);  // r0 = r0 - r1*r2
-  }
+  __ vmovsr(S2, R0);
+  __ vmovsr(S4, R2);
+  __ vcvtdi(D1, S2);
+  __ vcvtdi(D2, S4);
+  __ vdivd(D0, D1, D2);
+  __ vcvtid(S0, D0);
+  __ vmovrs(R1, S0);       // r1 = r0/r2
+  __ mls(R0, R1, R2, R0);  // r0 = r0 - r1*r2
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(QuotientRemainder, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef int64_t (*QuotientRemainder)(int64_t dividend, int64_t divisor)
-        DART_UNUSED;
-    EXPECT_EQ(0x1000400000da8LL,
-              EXECUTE_TEST_CODE_INT64_LL(QuotientRemainder, test->entry(),
-                                         0x12345678, 0x1234));
-  }
+  typedef int64_t (*QuotientRemainder)(int64_t dividend, int64_t divisor)
+      DART_UNUSED;
+  EXPECT_EQ(0x1000400000da8LL,
+            EXECUTE_TEST_CODE_INT64_LL(QuotientRemainder, test->entry(),
+                                       0x12345678, 0x1234));
 }
 
 ASSEMBLER_TEST_GENERATE(Multiply64To64, assembler) {
@@ -1437,332 +1368,308 @@
 
 // Make sure we can store and reload the D registers using vstmd and vldmd
 ASSEMBLER_TEST_GENERATE(VstmdVldmd, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ LoadDImmediate(D0, 0.0, R0);
-    __ LoadDImmediate(D1, 1.0, R0);
-    __ LoadDImmediate(D2, 2.0, R0);
-    __ LoadDImmediate(D3, 3.0, R0);
-    __ LoadDImmediate(D4, 4.0, R0);
-    __ vstmd(DB_W, SP, D0, 5);  // Push D0 - D4 onto the stack, dec SP
-    __ LoadDImmediate(D0, 0.0, R0);
-    __ LoadDImmediate(D1, 0.0, R0);
-    __ LoadDImmediate(D2, 0.0, R0);
-    __ LoadDImmediate(D3, 0.0, R0);
-    __ LoadDImmediate(D4, 0.0, R0);
-    __ vldmd(IA_W, SP, D0, 5);  // Pop stack into D0 - D4, inc SP
+  __ LoadDImmediate(D0, 0.0, R0);
+  __ LoadDImmediate(D1, 1.0, R0);
+  __ LoadDImmediate(D2, 2.0, R0);
+  __ LoadDImmediate(D3, 3.0, R0);
+  __ LoadDImmediate(D4, 4.0, R0);
+  __ vstmd(DB_W, SP, D0, 5);  // Push D0 - D4 onto the stack, dec SP
+  __ LoadDImmediate(D0, 0.0, R0);
+  __ LoadDImmediate(D1, 0.0, R0);
+  __ LoadDImmediate(D2, 0.0, R0);
+  __ LoadDImmediate(D3, 0.0, R0);
+  __ LoadDImmediate(D4, 0.0, R0);
+  __ vldmd(IA_W, SP, D0, 5);  // Pop stack into D0 - D4, inc SP
 
-    // Load success value into R0
-    __ mov(R0, Operand(42));
+  // Load success value into R0
+  __ mov(R0, Operand(42));
 
-    // Check that 4.0 is back in D4
-    __ LoadDImmediate(D5, 4.0, R1);
-    __ vcmpd(D4, D5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
+  // Check that 4.0 is back in D4
+  __ LoadDImmediate(D5, 4.0, R1);
+  __ vcmpd(D4, D5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
 
-    // Check that 3.0 is back in D3
-    __ LoadDImmediate(D5, 3.0, R1);
-    __ vcmpd(D3, D5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
+  // Check that 3.0 is back in D3
+  __ LoadDImmediate(D5, 3.0, R1);
+  __ vcmpd(D3, D5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
 
-    // Check that 2.0 is back in D2
-    __ LoadDImmediate(D5, 2.0, R1);
-    __ vcmpd(D2, D5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
+  // Check that 2.0 is back in D2
+  __ LoadDImmediate(D5, 2.0, R1);
+  __ vcmpd(D2, D5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
 
-    // Check that 1.0 is back in D1
-    __ LoadDImmediate(D5, 1.0, R1);
-    __ vcmpd(D1, D5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
-  }
+  // Check that 1.0 is back in D1
+  __ LoadDImmediate(D5, 1.0, R1);
+  __ vcmpd(D1, D5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(VstmdVldmd, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef int (*Tst)() DART_UNUSED;
-    EXPECT_EQ(42, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
-  }
+  typedef int (*Tst)() DART_UNUSED;
+  EXPECT_EQ(42, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
 }
 
 // Make sure we can store and reload the S registers using vstms and vldms
 ASSEMBLER_TEST_GENERATE(VstmsVldms, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ LoadSImmediate(S0, 0.0);
-    __ LoadSImmediate(S1, 1.0);
-    __ LoadSImmediate(S2, 2.0);
-    __ LoadSImmediate(S3, 3.0);
-    __ LoadSImmediate(S4, 4.0);
-    __ vstms(DB_W, SP, S0, S4);  // Push S0 - S4 onto the stack, dec SP
-    __ LoadSImmediate(S0, 0.0);
-    __ LoadSImmediate(S1, 0.0);
-    __ LoadSImmediate(S2, 0.0);
-    __ LoadSImmediate(S3, 0.0);
-    __ LoadSImmediate(S4, 0.0);
-    __ vldms(IA_W, SP, S0, S4);  // Pop stack into S0 - S4, inc SP
+  __ LoadSImmediate(S0, 0.0);
+  __ LoadSImmediate(S1, 1.0);
+  __ LoadSImmediate(S2, 2.0);
+  __ LoadSImmediate(S3, 3.0);
+  __ LoadSImmediate(S4, 4.0);
+  __ vstms(DB_W, SP, S0, S4);  // Push S0 - S4 onto the stack, dec SP
+  __ LoadSImmediate(S0, 0.0);
+  __ LoadSImmediate(S1, 0.0);
+  __ LoadSImmediate(S2, 0.0);
+  __ LoadSImmediate(S3, 0.0);
+  __ LoadSImmediate(S4, 0.0);
+  __ vldms(IA_W, SP, S0, S4);  // Pop stack into S0 - S4, inc SP
 
-    // Load success value into R0
-    __ mov(R0, Operand(42));
+  // Load success value into R0
+  __ mov(R0, Operand(42));
 
-    // Check that 4.0 is back in S4
-    __ LoadSImmediate(S5, 4.0);
-    __ vcmps(S4, S5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
+  // Check that 4.0 is back in S4
+  __ LoadSImmediate(S5, 4.0);
+  __ vcmps(S4, S5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
 
-    // Check that 3.0 is back in S3
-    __ LoadSImmediate(S5, 3.0);
-    __ vcmps(S3, S5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
+  // Check that 3.0 is back in S3
+  __ LoadSImmediate(S5, 3.0);
+  __ vcmps(S3, S5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
 
-    // Check that 2.0 is back in S2
-    __ LoadSImmediate(S5, 2.0);
-    __ vcmps(S2, S5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
+  // Check that 2.0 is back in S2
+  __ LoadSImmediate(S5, 2.0);
+  __ vcmps(S2, S5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
 
-    // Check that 1.0 is back in S1
-    __ LoadSImmediate(S5, 1.0);
-    __ vcmps(S1, S5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
-  }
+  // Check that 1.0 is back in S1
+  __ LoadSImmediate(S5, 1.0);
+  __ vcmps(S1, S5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(VstmsVldms, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef int (*Tst)() DART_UNUSED;
-    EXPECT_EQ(42, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
-  }
+  typedef int (*Tst)() DART_UNUSED;
+  EXPECT_EQ(42, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
 }
 
 // Make sure we can start somewhere other than D0
 ASSEMBLER_TEST_GENERATE(VstmdVldmd1, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ LoadDImmediate(D1, 1.0, R0);
-    __ LoadDImmediate(D2, 2.0, R0);
-    __ LoadDImmediate(D3, 3.0, R0);
-    __ LoadDImmediate(D4, 4.0, R0);
-    __ vstmd(DB_W, SP, D1, 4);  // Push D1 - D4 onto the stack, dec SP
-    __ LoadDImmediate(D1, 0.0, R0);
-    __ LoadDImmediate(D2, 0.0, R0);
-    __ LoadDImmediate(D3, 0.0, R0);
-    __ LoadDImmediate(D4, 0.0, R0);
-    __ vldmd(IA_W, SP, D1, 4);  // Pop stack into D1 - D4, inc SP
+  __ LoadDImmediate(D1, 1.0, R0);
+  __ LoadDImmediate(D2, 2.0, R0);
+  __ LoadDImmediate(D3, 3.0, R0);
+  __ LoadDImmediate(D4, 4.0, R0);
+  __ vstmd(DB_W, SP, D1, 4);  // Push D1 - D4 onto the stack, dec SP
+  __ LoadDImmediate(D1, 0.0, R0);
+  __ LoadDImmediate(D2, 0.0, R0);
+  __ LoadDImmediate(D3, 0.0, R0);
+  __ LoadDImmediate(D4, 0.0, R0);
+  __ vldmd(IA_W, SP, D1, 4);  // Pop stack into D1 - D4, inc SP
 
-    // Load success value into R0
-    __ mov(R0, Operand(42));
+  // Load success value into R0
+  __ mov(R0, Operand(42));
 
-    // Check that 4.0 is back in D4
-    __ LoadDImmediate(D5, 4.0, R1);
-    __ vcmpd(D4, D5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
+  // Check that 4.0 is back in D4
+  __ LoadDImmediate(D5, 4.0, R1);
+  __ vcmpd(D4, D5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
 
-    // Check that 3.0 is back in D3
-    __ LoadDImmediate(D5, 3.0, R1);
-    __ vcmpd(D3, D5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
+  // Check that 3.0 is back in D3
+  __ LoadDImmediate(D5, 3.0, R1);
+  __ vcmpd(D3, D5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
 
-    // Check that 2.0 is back in D2
-    __ LoadDImmediate(D5, 2.0, R1);
-    __ vcmpd(D2, D5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
+  // Check that 2.0 is back in D2
+  __ LoadDImmediate(D5, 2.0, R1);
+  __ vcmpd(D2, D5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
 
-    // Check that 1.0 is back in D1
-    __ LoadDImmediate(D5, 1.0, R1);
-    __ vcmpd(D1, D5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
-  }
+  // Check that 1.0 is back in D1
+  __ LoadDImmediate(D5, 1.0, R1);
+  __ vcmpd(D1, D5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(VstmdVldmd1, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef int (*Tst)() DART_UNUSED;
-    EXPECT_EQ(42, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
-  }
+  typedef int (*Tst)() DART_UNUSED;
+  EXPECT_EQ(42, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
 }
 
 // Make sure we can start somewhere other than S0
 ASSEMBLER_TEST_GENERATE(VstmsVldms1, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ LoadSImmediate(S1, 1.0);
-    __ LoadSImmediate(S2, 2.0);
-    __ LoadSImmediate(S3, 3.0);
-    __ LoadSImmediate(S4, 4.0);
-    __ vstms(DB_W, SP, S1, S4);  // Push S0 - S4 onto the stack, dec SP
-    __ LoadSImmediate(S1, 0.0);
-    __ LoadSImmediate(S2, 0.0);
-    __ LoadSImmediate(S3, 0.0);
-    __ LoadSImmediate(S4, 0.0);
-    __ vldms(IA_W, SP, S1, S4);  // Pop stack into S0 - S4, inc SP
+  __ LoadSImmediate(S1, 1.0);
+  __ LoadSImmediate(S2, 2.0);
+  __ LoadSImmediate(S3, 3.0);
+  __ LoadSImmediate(S4, 4.0);
+  __ vstms(DB_W, SP, S1, S4);  // Push S0 - S4 onto the stack, dec SP
+  __ LoadSImmediate(S1, 0.0);
+  __ LoadSImmediate(S2, 0.0);
+  __ LoadSImmediate(S3, 0.0);
+  __ LoadSImmediate(S4, 0.0);
+  __ vldms(IA_W, SP, S1, S4);  // Pop stack into S0 - S4, inc SP
 
-    // Load success value into R0
-    __ mov(R0, Operand(42));
+  // Load success value into R0
+  __ mov(R0, Operand(42));
 
-    // Check that 4.0 is back in S4
-    __ LoadSImmediate(S5, 4.0);
-    __ vcmps(S4, S5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
+  // Check that 4.0 is back in S4
+  __ LoadSImmediate(S5, 4.0);
+  __ vcmps(S4, S5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
 
-    // Check that 3.0 is back in S3
-    __ LoadSImmediate(S5, 3.0);
-    __ vcmps(S3, S5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
+  // Check that 3.0 is back in S3
+  __ LoadSImmediate(S5, 3.0);
+  __ vcmps(S3, S5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
 
-    // Check that 2.0 is back in S2
-    __ LoadSImmediate(S5, 2.0);
-    __ vcmps(S2, S5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
+  // Check that 2.0 is back in S2
+  __ LoadSImmediate(S5, 2.0);
+  __ vcmps(S2, S5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
 
-    // Check that 1.0 is back in S1
-    __ LoadSImmediate(S5, 1.0);
-    __ vcmps(S1, S5);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
-  }
+  // Check that 1.0 is back in S1
+  __ LoadSImmediate(S5, 1.0);
+  __ vcmps(S1, S5);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(VstmsVldms1, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef int (*Tst)() DART_UNUSED;
-    EXPECT_EQ(42, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
-  }
+  typedef int (*Tst)() DART_UNUSED;
+  EXPECT_EQ(42, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
 }
 
 // Make sure we can store the D registers using vstmd and
 // load them into a different set using vldmd
 ASSEMBLER_TEST_GENERATE(VstmdVldmd_off, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    // Save used callee-saved FPU registers.
-    __ vstmd(DB_W, SP, D8, 3);
-    __ LoadDImmediate(D0, 0.0, R0);
-    __ LoadDImmediate(D1, 1.0, R0);
-    __ LoadDImmediate(D2, 2.0, R0);
-    __ LoadDImmediate(D3, 3.0, R0);
-    __ LoadDImmediate(D4, 4.0, R0);
-    __ LoadDImmediate(D5, 5.0, R0);
-    __ vstmd(DB_W, SP, D0, 5);  // Push D0 - D4 onto the stack, dec SP
-    __ vldmd(IA_W, SP, D5, 5);  // Pop stack into D5 - D9, inc SP
+  // Save used callee-saved FPU registers.
+  __ vstmd(DB_W, SP, D8, 3);
+  __ LoadDImmediate(D0, 0.0, R0);
+  __ LoadDImmediate(D1, 1.0, R0);
+  __ LoadDImmediate(D2, 2.0, R0);
+  __ LoadDImmediate(D3, 3.0, R0);
+  __ LoadDImmediate(D4, 4.0, R0);
+  __ LoadDImmediate(D5, 5.0, R0);
+  __ vstmd(DB_W, SP, D0, 5);  // Push D0 - D4 onto the stack, dec SP
+  __ vldmd(IA_W, SP, D5, 5);  // Pop stack into D5 - D9, inc SP
 
-    // Load success value into R0
-    __ mov(R0, Operand(42));
+  // Load success value into R0
+  __ mov(R0, Operand(42));
 
-    // Check that 4.0 is in D9
-    __ LoadDImmediate(D10, 4.0, R1);
-    __ vcmpd(D9, D10);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
+  // Check that 4.0 is in D9
+  __ LoadDImmediate(D10, 4.0, R1);
+  __ vcmpd(D9, D10);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
 
-    // Check that 3.0 is in D8
-    __ LoadDImmediate(D10, 3.0, R1);
-    __ vcmpd(D8, D10);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
+  // Check that 3.0 is in D8
+  __ LoadDImmediate(D10, 3.0, R1);
+  __ vcmpd(D8, D10);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
 
-    // Check that 2.0 is in D7
-    __ LoadDImmediate(D10, 2.0, R1);
-    __ vcmpd(D7, D10);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
+  // Check that 2.0 is in D7
+  __ LoadDImmediate(D10, 2.0, R1);
+  __ vcmpd(D7, D10);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
 
-    // Check that 1.0 is in D6
-    __ LoadDImmediate(D10, 1.0, R1);
-    __ vcmpd(D6, D10);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
+  // Check that 1.0 is in D6
+  __ LoadDImmediate(D10, 1.0, R1);
+  __ vcmpd(D6, D10);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
 
-    // Check that 0.0 is in D5
-    __ LoadDImmediate(D10, 0.0, R1);
-    __ vcmpd(D5, D10);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
+  // Check that 0.0 is in D5
+  __ LoadDImmediate(D10, 0.0, R1);
+  __ vcmpd(D5, D10);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure into R0 if NE
 
-    // Restore used callee-saved FPU registers.
-    __ vldmd(IA_W, SP, D8, 3);
-  }
+  // Restore used callee-saved FPU registers.
+  __ vldmd(IA_W, SP, D8, 3);
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(VstmdVldmd_off, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef int (*Tst)() DART_UNUSED;
-    EXPECT_EQ(42, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
-  }
+  typedef int (*Tst)() DART_UNUSED;
+  EXPECT_EQ(42, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
 }
 
 // Make sure we can start somewhere other than S0
 ASSEMBLER_TEST_GENERATE(VstmsVldms_off, assembler) {
-  if (TargetCPUFeatures::vfp_supported()) {
-    __ LoadSImmediate(S0, 0.0);
-    __ LoadSImmediate(S1, 1.0);
-    __ LoadSImmediate(S2, 2.0);
-    __ LoadSImmediate(S3, 3.0);
-    __ LoadSImmediate(S4, 4.0);
-    __ LoadSImmediate(S5, 5.0);
-    __ vstms(DB_W, SP, S0, S4);  // Push S0 - S4 onto the stack, dec SP
-    __ vldms(IA_W, SP, S5, S9);  // Pop stack into S5 - S9, inc SP
+  __ LoadSImmediate(S0, 0.0);
+  __ LoadSImmediate(S1, 1.0);
+  __ LoadSImmediate(S2, 2.0);
+  __ LoadSImmediate(S3, 3.0);
+  __ LoadSImmediate(S4, 4.0);
+  __ LoadSImmediate(S5, 5.0);
+  __ vstms(DB_W, SP, S0, S4);  // Push S0 - S4 onto the stack, dec SP
+  __ vldms(IA_W, SP, S5, S9);  // Pop stack into S5 - S9, inc SP
 
-    // Load success value into R0
-    __ mov(R0, Operand(42));
+  // Load success value into R0
+  __ mov(R0, Operand(42));
 
-    // Check that 4.0 is in S9
-    __ LoadSImmediate(S10, 4.0);
-    __ vcmps(S9, S10);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
+  // Check that 4.0 is in S9
+  __ LoadSImmediate(S10, 4.0);
+  __ vcmps(S9, S10);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
 
-    // Check that 3.0 is in S8
-    __ LoadSImmediate(S10, 3.0);
-    __ vcmps(S8, S10);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
+  // Check that 3.0 is in S8
+  __ LoadSImmediate(S10, 3.0);
+  __ vcmps(S8, S10);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
 
-    // Check that 2.0 is in S7
-    __ LoadSImmediate(S10, 2.0);
-    __ vcmps(S7, S10);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
+  // Check that 2.0 is in S7
+  __ LoadSImmediate(S10, 2.0);
+  __ vcmps(S7, S10);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
 
-    // Check that 1.0 is back in S6
-    __ LoadSImmediate(S10, 1.0);
-    __ vcmps(S6, S10);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
+  // Check that 1.0 is back in S6
+  __ LoadSImmediate(S10, 1.0);
+  __ vcmps(S6, S10);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
 
-    // Check that 0.0 is back in S5
-    __ LoadSImmediate(S10, 0.0);
-    __ vcmps(S5, S10);
-    __ vmstat();
-    __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
-  }
+  // Check that 0.0 is back in S5
+  __ LoadSImmediate(S10, 0.0);
+  __ vcmps(S5, S10);
+  __ vmstat();
+  __ mov(R0, Operand(0), NE);  // Put failure value into R0 if NE
   __ Ret();
 }
 
 ASSEMBLER_TEST_RUN(VstmsVldms_off, test) {
   EXPECT(test != NULL);
-  if (TargetCPUFeatures::vfp_supported()) {
-    typedef int (*Tst)() DART_UNUSED;
-    EXPECT_EQ(42, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
-  }
+  typedef int (*Tst)() DART_UNUSED;
+  EXPECT_EQ(42, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
 }
 
 //                                          3         2         1         0
@@ -1942,11 +1849,9 @@
   HostCPUFeatures::set_integer_division_supported(orig);
   __ Ret();
 #else
-  if (TargetCPUFeatures::can_divide()) {
-    __ mov(R0, Operand(27));
-    __ mov(R1, Operand(9));
-    __ IntegerDivide(R0, R0, R1, D0, D1);
-  }
+  __ mov(R0, Operand(27));
+  __ mov(R1, Operand(9));
+  __ IntegerDivide(R0, R0, R1, D0, D1);
   __ Ret();
 #endif
 }
@@ -1956,36 +1861,28 @@
 #if defined(USING_SIMULATOR)
   bool orig = TargetCPUFeatures::integer_division_supported();
   HostCPUFeatures::set_integer_division_supported(true);
-  if (TargetCPUFeatures::can_divide()) {
-    typedef int (*Tst)() DART_UNUSED;
-    EXPECT_EQ(3, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
-  }
+  typedef int (*Tst)() DART_UNUSED;
+  EXPECT_EQ(3, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
   HostCPUFeatures::set_integer_division_supported(orig);
 #else
-  if (TargetCPUFeatures::can_divide()) {
-    typedef int (*Tst)() DART_UNUSED;
-    EXPECT_EQ(3, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
-  }
+  typedef int (*Tst)() DART_UNUSED;
+  EXPECT_EQ(3, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
 #endif
 }
 
 ASSEMBLER_TEST_GENERATE(IntDiv_unsupported, assembler) {
 #if defined(USING_SIMULATOR)
-  if (TargetCPUFeatures::can_divide()) {
     bool orig = TargetCPUFeatures::integer_division_supported();
     HostCPUFeatures::set_integer_division_supported(false);
     __ mov(R0, Operand(27));
     __ mov(R1, Operand(9));
     __ IntegerDivide(R0, R0, R1, D0, D1);
     HostCPUFeatures::set_integer_division_supported(orig);
-  }
   __ Ret();
 #else
-  if (TargetCPUFeatures::can_divide()) {
-    __ mov(R0, Operand(27));
-    __ mov(R1, Operand(9));
-    __ IntegerDivide(R0, R0, R1, D0, D1);
-  }
+  __ mov(R0, Operand(27));
+  __ mov(R1, Operand(9));
+  __ IntegerDivide(R0, R0, R1, D0, D1);
   __ Ret();
 #endif
 }
@@ -1995,16 +1892,12 @@
 #if defined(USING_SIMULATOR)
   bool orig = TargetCPUFeatures::integer_division_supported();
   HostCPUFeatures::set_integer_division_supported(false);
-  if (TargetCPUFeatures::can_divide()) {
-    typedef int (*Tst)() DART_UNUSED;
-    EXPECT_EQ(3, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
-  }
+  typedef int (*Tst)() DART_UNUSED;
+  EXPECT_EQ(3, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
   HostCPUFeatures::set_integer_division_supported(orig);
 #else
-  if (TargetCPUFeatures::can_divide()) {
-    typedef int (*Tst)() DART_UNUSED;
-    EXPECT_EQ(3, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
-  }
+  typedef int (*Tst)() DART_UNUSED;
+  EXPECT_EQ(3, EXECUTE_TEST_CODE_INT32(Tst, test->entry()));
 #endif
 }
 
diff --git a/runtime/vm/compiler/assembler/assembler_ia32_test.cc b/runtime/vm/compiler/assembler/assembler_ia32_test.cc
index 4f98613..43c4818 100644
--- a/runtime/vm/compiler/assembler/assembler_ia32_test.cc
+++ b/runtime/vm/compiler/assembler/assembler_ia32_test.cc
@@ -15,7 +15,7 @@
 #define EXPECT_DISASSEMBLY(expected)
 #else
 #define EXPECT_DISASSEMBLY(expected)                                           \
-  EXPECT_STREQ(expected, test->BlankedDisassembly())
+  EXPECT_STREQ(expected, test->RelativeDisassembly())
 #endif
 
 namespace dart {
@@ -119,12 +119,12 @@
       "mov eax,[esp-0x4]\n"
       "mov eax,[ebp-0x4]\n"
       "mov eax,[eax-0x4]\n"
-      "mov eax,[esp+0x...]\n"
-      "mov eax,[ebp+0x...]\n"
-      "mov eax,[eax+0x...]\n"
-      "mov eax,[esp-0x...]\n"
-      "mov eax,[ebp-0x...]\n"
-      "mov eax,[eax-0x...]\n"
+      "mov eax,[esp+0x400]\n"
+      "mov eax,[ebp+0x400]\n"
+      "mov eax,[eax+0x400]\n"
+      "mov eax,[esp-0x400]\n"
+      "mov eax,[ebp-0x400]\n"
+      "mov eax,[eax-0x400]\n"
       "mov eax,[eax]\n"
       "mov eax,[eax+0x1]\n"
       "mov eax,[eax+0x2]\n"
@@ -133,8 +133,8 @@
       "mov eax,[eax+0x1]\n"
       "mov eax,[ebp*2+0x4]\n"
       "mov eax,[eax*2+0x4]\n"
-      "mov eax,[ebp*2+0x...]\n"
-      "mov eax,[eax*2+0x...]\n"
+      "mov eax,[ebp*2+0x400]\n"
+      "mov eax,[eax*2+0x400]\n"
       "mov eax,[eax+ebp*2]\n"
       "mov eax,[eax+eax*2]\n"
       "mov eax,[ebp+ebp*2+0]\n"
@@ -147,12 +147,12 @@
       "mov eax,[ebp+eax*2+0x4]\n"
       "mov eax,[esp+ebp*2+0x4]\n"
       "mov eax,[esp+eax*2+0x4]\n"
-      "mov eax,[eax+ebp*2+0x...]\n"
-      "mov eax,[eax+eax*2+0x...]\n"
-      "mov eax,[ebp+ebp*2+0x...]\n"
-      "mov eax,[ebp+eax*2+0x...]\n"
-      "mov eax,[esp+ebp*2+0x...]\n"
-      "mov eax,[esp+eax*2+0x...]\n");
+      "mov eax,[eax+ebp*2+0x400]\n"
+      "mov eax,[eax+eax*2+0x400]\n"
+      "mov eax,[ebp+ebp*2+0x400]\n"
+      "mov eax,[ebp+eax*2+0x400]\n"
+      "mov eax,[esp+ebp*2+0x400]\n"
+      "mov eax,[esp+eax*2+0x400]\n");
 }
 
 ASSEMBLER_TEST_GENERATE(JumpAroundCrash, assembler) {
@@ -180,23 +180,23 @@
   typedef void (*JumpAroundCrashCode)();
   reinterpret_cast<JumpAroundCrashCode>(test->entry())();
   EXPECT_DISASSEMBLY(
-      "jo 0x........\n"
-      "jno 0x........\n"
-      "jc 0x........\n"
-      "jnc 0x........\n"
-      "jz 0x........\n"
-      "jnz 0x........\n"
-      "jna 0x........\n"
-      "ja 0x........\n"
-      "js 0x........\n"
-      "jns 0x........\n"
-      "jpe 0x........\n"
-      "jpo 0x........\n"
-      "jl 0x........\n"
-      "jge 0x........\n"
-      "jle 0x........\n"
-      "jg 0x........\n"
-      "jmp 0x........\n"
+      "jo +108\n"
+      "jno +102\n"
+      "jc +96\n"
+      "jnc +90\n"
+      "jz +84\n"
+      "jnz +78\n"
+      "jna +72\n"
+      "ja +66\n"
+      "js +60\n"
+      "jns +54\n"
+      "jpe +48\n"
+      "jpo +42\n"
+      "jl +36\n"
+      "jge +30\n"
+      "jle +24\n"
+      "jg +18\n"
+      "jmp +12\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "ret\n");
@@ -225,23 +225,23 @@
   typedef void (*NearJumpAroundCrashCode)();
   reinterpret_cast<NearJumpAroundCrashCode>(test->entry())();
   EXPECT_DISASSEMBLY(
-      "jo 0x........\n"
-      "jno 0x........\n"
-      "jc 0x........\n"
-      "jnc 0x........\n"
-      "jz 0x........\n"
-      "jnz 0x........\n"
-      "jna 0x........\n"
-      "ja 0x........\n"
-      "js 0x........\n"
-      "jns 0x........\n"
-      "jpe 0x........\n"
-      "jpo 0x........\n"
-      "jl 0x........\n"
-      "jge 0x........\n"
-      "jle 0x........\n"
-      "jg 0x........\n"
-      "jmp 0x........\n"
+      "jo +41\n"
+      "jno +39\n"
+      "jc +37\n"
+      "jnc +35\n"
+      "jz +33\n"
+      "jnz +31\n"
+      "jna +29\n"
+      "ja +27\n"
+      "js +25\n"
+      "jns +23\n"
+      "jpe +21\n"
+      "jpo +19\n"
+      "jl +17\n"
+      "jge +15\n"
+      "jle +13\n"
+      "jg +11\n"
+      "jmp +9\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "ret\n");
@@ -268,7 +268,7 @@
       "add eax,2\n"
       "inc ecx\n"
       "cmp ecx,0x57\n"
-      "jl 0x........\n"
+      "jl -7\n"
       "ret\n");
 }
 
@@ -289,9 +289,9 @@
   EXPECT_EQ(1, reinterpret_cast<CmpbCode>(test->entry())());
   EXPECT_DISASSEMBLY(
       "mov eax,1\n"
-      "push 0x........\n"
+      "push 0xffffff11\n"
       "cmpb [esp],0x11\n"
-      "jz 0x........\n"
+      "jz +7\n"
       "mov eax,0\n"
       "pop ecx\n"
       "ret\n");
@@ -317,7 +317,7 @@
   EXPECT_DISASSEMBLY(
       "mov eax,1\n"
       "mov ecx,0\n"
-      "push 0x........\n"
+      "push 0xffffff11\n"
       "testb [esp],0x10\n"
       "cmovz eax,ecx\n"
       "testb [esp],0x20\n"
@@ -372,7 +372,7 @@
   typedef int (*PopcntCode)();
   EXPECT_EQ(36, reinterpret_cast<PopcntCode>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "mov ecx,0x........\n"
+      "mov ecx,0xffffffff\n"
       "popcnt eax,ecx\n"
       "mov ecx,0xf\n"
       "popcnt ecx,ecx\n"
@@ -396,7 +396,7 @@
   typedef int (*LzcntCode)();
   EXPECT_EQ(44, reinterpret_cast<LzcntCode>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "mov ecx,0x...\n"
+      "mov ecx,0xf00\n"
       "lzcnt eax,ecx\n"
       "mov ecx,0xf0\n"
       "lzcnt ecx,ecx\n"
@@ -536,7 +536,7 @@
       "mov eax,2\n"
       "mov ecx,4\n"
       "imul eax,ecx\n"
-      "imul eax,eax,0x...\n"
+      "imul eax,eax,0x3e8\n"
       "ret\n");
 }
 
@@ -554,8 +554,8 @@
   EXPECT_EQ(0, reinterpret_cast<OverflowSignedMultiply>(test->entry())());
   EXPECT_DISASSEMBLY(
       "mov edx,0\n"
-      "mov eax,0x........\n"
-      "mov ecx,0x........\n"
+      "mov eax,0x0fffffff\n"
+      "mov ecx,0x0fffffff\n"
       "imul eax,ecx\n"
       "imul eax,edx\n"
       "ret\n");
@@ -580,7 +580,7 @@
       "mov ebx,2\n"
       "mov ecx,4\n"
       "imul ebx,ecx\n"
-      "imul ebx,ebx,0x...\n"
+      "imul ebx,ebx,0x3e8\n"
       "mov eax,ebx\n"
       "pop ebx\n"
       "ret\n");
@@ -622,7 +622,7 @@
   EXPECT_EQ(31, call(-1));
   EXPECT_DISASSEMBLY(
       "mov ecx,[esp+0x4]\n"
-      "mov eax,0x...\n"
+      "mov eax,0x29a\n"
       "bsr eax,ecx\n"
       "ret\n");
 }
@@ -644,7 +644,7 @@
   EXPECT_EQ(0xff - 1 + 0xffff, reinterpret_cast<MoveExtend>(test->entry())());
   EXPECT_DISASSEMBLY(
       "push ebx\n"
-      "mov edx,0x........\n"
+      "mov edx,0x1234ffff\n"
       "movzxb eax,edx\n"
       "movsxw ebx,edx\n"
       "movzxw ecx,edx\n"
@@ -676,7 +676,7 @@
             reinterpret_cast<MoveExtendMemory>(test->entry())());
   EXPECT_DISASSEMBLY(
       "push ebx\n"
-      "mov edx,0x........\n"
+      "mov edx,0x1234ffff\n"
       "push edx\n"
       "movzxb eax,[esp]\n"
       "movsxw ebx,[esp]\n"
@@ -724,12 +724,12 @@
   EXPECT_DISASSEMBLY(
       "mov ecx,0x2a\n"
       "xor ecx,ecx\n"
-      "or ecx,0x...\n"
-      "mov eax,0x...\n"
+      "or ecx,0x100\n"
+      "mov eax,0x648\n"
       "or ecx,eax\n"
-      "mov eax,0x....\n"
+      "mov eax,0xfff0\n"
       "and ecx,eax\n"
-      "push 0x....\n"
+      "push 0xf6ff\n"
       "and ecx,[esp]\n"
       "pop eax\n"
       "mov eax,1\n"
@@ -943,121 +943,121 @@
       "mov eax,4\n"
       "and eax,2\n"
       "cmp eax,0\n"
-      "jz 0x........\n"
+      "jz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov ecx,4\n"
       "and ecx,4\n"
       "cmp ecx,0\n"
-      "jnz 0x........\n"
+      "jnz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov eax,0\n"
       "or eax,0\n"
       "cmp eax,0\n"
-      "jz 0x........\n"
+      "jz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov eax,4\n"
       "or eax,0\n"
       "cmp eax,0\n"
-      "jnz 0x........\n"
+      "jnz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov eax,1\n"
       "shl eax,1\n"
       "cmp eax,2\n"
-      "jz 0x........\n"
+      "jz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov eax,1\n"
       "shl eax,3\n"
       "cmp eax,8\n"
-      "jz 0x........\n"
+      "jz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov eax,2\n"
       "shr eax,1\n"
       "cmp eax,1\n"
-      "jz 0x........\n"
+      "jz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov eax,8\n"
       "shr eax,3\n"
       "cmp eax,1\n"
-      "jz 0x........\n"
+      "jz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov eax,1\n"
       "mov ecx,3\n"
       "shl eax,cl\n"
       "cmp eax,8\n"
-      "jz 0x........\n"
+      "jz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov eax,8\n"
       "mov ecx,3\n"
       "shr eax,cl\n"
       "cmp eax,1\n"
-      "jz 0x........\n"
+      "jz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov eax,1\n"
       "shl eax,31\n"
       "shr eax,3\n"
-      "cmp eax,0x........\n"
-      "jz 0x........\n"
+      "cmp eax,0x10000000\n"
+      "jz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov eax,1\n"
       "shl eax,31\n"
       "sar eax,3\n"
-      "cmp eax,0x........\n"
-      "jz 0x........\n"
+      "cmp eax,0xf0000000\n"
+      "jz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov eax,1\n"
       "mov ecx,3\n"
       "shl eax,31\n"
       "sar eax,cl\n"
-      "cmp eax,0x........\n"
-      "jz 0x........\n"
+      "cmp eax,0xf0000000\n"
+      "jz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "sub esp,4\n"
-      "mov [esp],-0x........\n"
+      "mov [esp],-0x80000000\n"
       "mov eax,0\n"
       "mov ecx,3\n"
       "sar [esp],cl\n"
       "shrd [esp],eax,cl\n"
-      "cmp [esp],0x........\n"
-      "jz 0x........\n"
+      "cmp [esp],0x1e000000\n"
+      "jz +7\n"
       "int3\n"
       "add esp,4\n"
       "sub esp,4\n"
-      "mov [esp],-0x........\n"
-      "mov eax,0x........\n"
+      "mov [esp],-0x01000000\n"
+      "mov eax,0xffffffff\n"
       "mov ecx,2\n"
       "shl [esp],cl\n"
       "shld [esp],eax,cl\n"
-      "cmp [esp],0x........\n"
-      "jz 0x........\n"
+      "cmp [esp],0xf0000003\n"
+      "jz +7\n"
       "int3\n"
       "add esp,4\n"
-      "mov edx,0x........\n"
+      "mov edx,0x80000000\n"
       "mov eax,0\n"
       "mov ecx,3\n"
       "sar edx,3\n"
       "shrd edx,eax,3\n"
-      "cmp edx,0x........\n"
-      "jz 0x........\n"
+      "cmp edx,0x1e000000\n"
+      "jz +7\n"
       "int3\n"
-      "mov edx,0x........\n"
-      "mov eax,0x........\n"
+      "mov edx,0xff000000\n"
+      "mov eax,0xffffffff\n"
       "shl edx,2\n"
       "shld edx,eax,2\n"
-      "cmp edx,0x........\n"
-      "jz 0x........\n"
+      "cmp edx,0xf0000003\n"
+      "jz +7\n"
       "int3\n"
       "mov eax,0\n"
       "ret\n");
@@ -1125,28 +1125,28 @@
       "mov eax,4\n"
       "mov ecx,2\n"
       "test eax,ecx\n"
-      "jz 0x........\n"
+      "jz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov edx,4\n"
       "mov ecx,4\n"
       "test edx,ecx\n"
-      "jnz 0x........\n"
+      "jnz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov eax,0\n"
       "test al,0\n"
-      "jz 0x........\n"
+      "jz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov ebx,4\n"
       "testb ebx,4\n"
-      "jnz 0x........\n"
+      "jnz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov ebx,0xff\n"
       "testb ebx,0xff\n"
-      "jnz 0x........\n"
+      "jnz +13\n"
       "mov eax,0\n"
       "mov [eax],eax\n"
       "mov eax,0\n"
@@ -1217,7 +1217,7 @@
   typedef int (*SignedDivide)();
   EXPECT_EQ(-87 / 42, reinterpret_cast<SignedDivide>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0xffffffa9\n"
       "mov edx,0x7b\n"
       "cdq\n"
       "mov ecx,0x2a\n"
@@ -1237,9 +1237,9 @@
   typedef int (*UnsignedDivide)();
   EXPECT_EQ(0x42, reinterpret_cast<UnsignedDivide>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0xffffffbe\n"
       "mov edx,0x41\n"
-      "mov ecx,0x........\n"
+      "mov ecx,0xffffffff\n"
       "div (eax,edx),ecx\n"
       "ret\n");
 }
@@ -1256,8 +1256,8 @@
   typedef int (*Exchange)();
   EXPECT_EQ(987654321 - 123456789, reinterpret_cast<Exchange>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
-      "mov edx,0x........\n"
+      "mov eax,0x075bcd15\n"
+      "mov edx,0x3ade68b1\n"
       "xchg eax,edx\n"
       "sub eax,edx\n"
       "ret\n");
@@ -1358,7 +1358,7 @@
   float res = reinterpret_cast<SingleFPMovesCode>(test->entry())();
   EXPECT_EQ(234.0f, res);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x436a0000\n"
       "movd xmm0,eax\n"
       "movss ecx,xmm0\n"
       "movss edx,xmm1\n"
@@ -1397,7 +1397,7 @@
   EXPECT_DISASSEMBLY(
       "push ebx\n"
       "push ecx\n"
-      "mov ebx,0x........\n"
+      "mov ebx,0x436a0000\n"
       "movd xmm0,ebx\n"
       "movss ecx,xmm0\n"
       "movd ecx,xmm1\n"
@@ -1426,7 +1426,7 @@
   int res = reinterpret_cast<SingleFPUStackMovesCode>(test->entry())();
   EXPECT_EQ(234.0f, (bit_cast<float, int>(res)));
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x436a0000\n"
       "push eax\n"
       "fld_s [esp]\n"
       "xor ecx,ecx\n"
@@ -1458,9 +1458,9 @@
   float res = reinterpret_cast<SingleFPOperationsCode>(test->entry())();
   EXPECT_FLOAT_EQ(14.7f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x4144cccd\n"
       "movd xmm0,eax\n"
-      "mov eax,0x........\n"
+      "mov eax,0x4059999a\n"
       "movd xmm1,eax\n"
       "addss xmm0,xmm1\n"
       "mulss xmm0,xmm1\n"
@@ -1498,10 +1498,10 @@
   float res = reinterpret_cast<PackedFPOperationsCode>(test->entry())();
   EXPECT_FLOAT_EQ(14.7f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x4144cccd\n"
       "movd xmm0,eax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "mov eax,0x........\n"
+      "mov eax,0x4059999a\n"
       "movd xmm1,eax\n"
       "shufps xmm1,xmm1 [0]\n"
       "addps xmm0,xmm1\n"
@@ -1577,7 +1577,7 @@
   float res = reinterpret_cast<PackedFPOperations2Code>(test->entry())();
   EXPECT_FLOAT_EQ(0.0f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x40800000\n"
       "movd xmm0,eax\n"
       "shufps xmm0,xmm0 [0]\n"
       "movaps xmm1,xmm0\n"
@@ -1610,10 +1610,10 @@
   uint32_t res = reinterpret_cast<PackedCompareEQCode>(test->entry())();
   EXPECT_EQ(static_cast<uword>(0x0), res);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x40000000\n"
       "movd xmm0,eax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "mov eax,0x........\n"
+      "mov eax,0x40800000\n"
       "movd xmm1,eax\n"
       "shufps xmm1,xmm1 [0]\n"
       "cmpps xmm0,xmm1 [eq]\n"
@@ -1641,10 +1641,10 @@
   uint32_t res = reinterpret_cast<PackedCompareNEQCode>(test->entry())();
   EXPECT_EQ(static_cast<uword>(0xFFFFFFFF), res);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x40000000\n"
       "movd xmm0,eax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "mov eax,0x........\n"
+      "mov eax,0x40800000\n"
       "movd xmm1,eax\n"
       "shufps xmm1,xmm1 [0]\n"
       "cmpps xmm0,xmm1 [neq]\n"
@@ -1672,10 +1672,10 @@
   uint32_t res = reinterpret_cast<PackedCompareLTCode>(test->entry())();
   EXPECT_EQ(static_cast<uword>(0xFFFFFFFF), res);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x40000000\n"
       "movd xmm0,eax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "mov eax,0x........\n"
+      "mov eax,0x40800000\n"
       "movd xmm1,eax\n"
       "shufps xmm1,xmm1 [0]\n"
       "cmpps xmm0,xmm1 [lt]\n"
@@ -1703,10 +1703,10 @@
   uint32_t res = reinterpret_cast<PackedCompareLECode>(test->entry())();
   EXPECT_EQ(static_cast<uword>(0xFFFFFFFF), res);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x40000000\n"
       "movd xmm0,eax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "mov eax,0x........\n"
+      "mov eax,0x40800000\n"
       "movd xmm1,eax\n"
       "shufps xmm1,xmm1 [0]\n"
       "cmpps xmm0,xmm1 [le]\n"
@@ -1734,10 +1734,10 @@
   uint32_t res = reinterpret_cast<PackedCompareNLTCode>(test->entry())();
   EXPECT_EQ(static_cast<uword>(0x0), res);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x40000000\n"
       "movd xmm0,eax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "mov eax,0x........\n"
+      "mov eax,0x40800000\n"
       "movd xmm1,eax\n"
       "shufps xmm1,xmm1 [0]\n"
       "cmpps xmm0,xmm1 [nlt]\n"
@@ -1765,10 +1765,10 @@
   uint32_t res = reinterpret_cast<PackedCompareNLECode>(test->entry())();
   EXPECT_EQ(static_cast<uword>(0x0), res);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x40000000\n"
       "movd xmm0,eax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "mov eax,0x........\n"
+      "mov eax,0x40800000\n"
       "movd xmm1,eax\n"
       "shufps xmm1,xmm1 [0]\n"
       "cmpps xmm0,xmm1 [nle]\n"
@@ -1798,10 +1798,10 @@
   float res = reinterpret_cast<PackedNegateCode>(test->entry())();
   EXPECT_FLOAT_EQ(-12.3f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x4144cccd\n"
       "movd xmm0,eax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "xorps xmm0,[rip+0x.......]\n"
+      "xorps xmm0,[0x.......]\n"
       "shufps xmm0,xmm0 [aa]\n"
       "push eax\n"
       "movss [esp],xmm0\n"
@@ -1829,10 +1829,10 @@
   float res = reinterpret_cast<PackedAbsoluteCode>(test->entry())();
   EXPECT_FLOAT_EQ(15.3f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0xc174cccd\n"
       "movd xmm0,eax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "andps xmm0,[rip+0x.......]\n"
+      "andps xmm0,[0x.......]\n"
       "shufps xmm0,xmm0 [aa]\n"
       "push eax\n"
       "movss [esp],xmm0\n"
@@ -1858,10 +1858,10 @@
   float res = reinterpret_cast<PackedSetWZeroCode>(test->entry())();
   EXPECT_FLOAT_EQ(0.0f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x4144cccd\n"
       "movd xmm0,eax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "andps xmm0,[rip+0x.......]\n"
+      "andps xmm0,[0x.......]\n"
       "shufps xmm0,xmm0 [ff]\n"
       "push eax\n"
       "movss [esp],xmm0\n"
@@ -1887,10 +1887,10 @@
   float res = reinterpret_cast<PackedMinCode>(test->entry())();
   EXPECT_FLOAT_EQ(2.0f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x40000000\n"
       "movd xmm0,eax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "mov eax,0x........\n"
+      "mov eax,0x40800000\n"
       "movd xmm1,eax\n"
       "shufps xmm1,xmm1 [0]\n"
       "minps xmm0,xmm1\n"
@@ -1918,10 +1918,10 @@
   float res = reinterpret_cast<PackedMaxCode>(test->entry())();
   EXPECT_FLOAT_EQ(4.0f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x40000000\n"
       "movd xmm0,eax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "mov eax,0x........\n"
+      "mov eax,0x40800000\n"
       "movd xmm1,eax\n"
       "shufps xmm1,xmm1 [0]\n"
       "maxps xmm0,xmm1\n"
@@ -1961,8 +1961,8 @@
   uint32_t res = reinterpret_cast<PackedLogicalOrCode>(test->entry())();
   EXPECT_EQ(0xFFFFFFFF, res);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "movups xmm1,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "movups xmm1,[0x.......]\n"
       "orps xmm0,xmm1\n"
       "push eax\n"
       "movss [esp],xmm0\n"
@@ -1999,8 +1999,8 @@
   uint32_t res = reinterpret_cast<PackedLogicalAndCode>(test->entry())();
   EXPECT_EQ(static_cast<uword>(0x0000F000), res);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "andps xmm0,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "andps xmm0,[0x.......]\n"
       "push eax\n"
       "movss [esp],xmm0\n"
       "fld_s [esp]\n"
@@ -2030,8 +2030,8 @@
   uint32_t res = reinterpret_cast<PackedLogicalNotCode>(test->entry())();
   EXPECT_EQ(static_cast<uword>(0x0), res);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "xorps xmm0,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "xorps xmm0,[0x.......]\n"
       "push eax\n"
       "movss [esp],xmm0\n"
       "fld_s [esp]\n"
@@ -2076,8 +2076,8 @@
   float res = reinterpret_cast<PackedMoveHighLow>(test->entry())();
   EXPECT_FLOAT_EQ(15.0f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "movups xmm1,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "movups xmm1,[0x.......]\n"
       "movhlps xmm0,xmm1\n"
       "xorps xmm1,xmm1\n"
       "movaps xmm1,xmm0\n"
@@ -2128,8 +2128,8 @@
   float res = reinterpret_cast<PackedMoveLowHigh>(test->entry())();
   EXPECT_FLOAT_EQ(11.0f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "movups xmm1,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "movups xmm1,[0x.......]\n"
       "movlhps xmm0,xmm1\n"
       "xorps xmm1,xmm1\n"
       "movaps xmm1,xmm0\n"
@@ -2179,8 +2179,8 @@
   float res = reinterpret_cast<PackedUnpackLow>(test->entry())();
   EXPECT_FLOAT_EQ(11.0f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "movups xmm1,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "movups xmm1,[0x.......]\n"
       "unpcklps xmm0,xmm1\n"
       "movaps xmm1,xmm0\n"
       "shufps xmm0,xmm0 [55]\n"
@@ -2229,8 +2229,8 @@
   float res = reinterpret_cast<PackedUnpackHigh>(test->entry())();
   EXPECT_FLOAT_EQ(7.0f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "movups xmm1,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "movups xmm1,[0x.......]\n"
       "unpckhps xmm0,xmm1\n"
       "movaps xmm1,xmm0\n"
       "shufps xmm0,xmm0 [0]\n"
@@ -2279,8 +2279,8 @@
   float res = reinterpret_cast<PackedUnpackLowPair>(test->entry())();
   EXPECT_FLOAT_EQ(6.0f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "movups xmm1,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "movups xmm1,[0x.......]\n"
       "unpcklpd xmm0,xmm1\n"
       "movaps xmm1,xmm0\n"
       "shufps xmm0,xmm0 [0]\n"
@@ -2329,8 +2329,8 @@
   float res = reinterpret_cast<PackedUnpackHighPair>(test->entry())();
   EXPECT_FLOAT_EQ(12.0f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "movups xmm1,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "movups xmm1,[0x.......]\n"
       "unpckhpd xmm0,xmm1\n"
       "movaps xmm1,xmm0\n"
       "shufps xmm0,xmm0 [55]\n"
@@ -2369,8 +2369,8 @@
   double res = reinterpret_cast<PackedDoubleAdd>(test->entry())();
   EXPECT_FLOAT_EQ(4.0, res, 0.000001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "movups xmm1,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "movups xmm1,[0x.......]\n"
       "addpd xmm0,xmm1\n"
       "push eax\n"
       "push eax\n"
@@ -2407,8 +2407,8 @@
   double res = reinterpret_cast<PackedDoubleSub>(test->entry())();
   EXPECT_FLOAT_EQ(-2.0, res, 0.000001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "movups xmm1,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "movups xmm1,[0x.......]\n"
       "subpd xmm0,xmm1\n"
       "push eax\n"
       "push eax\n"
@@ -2440,8 +2440,8 @@
   double res = reinterpret_cast<PackedDoubleNegate>(test->entry())();
   EXPECT_FLOAT_EQ(-1.0, res, 0.000001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "xorpd xmm0,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "xorpd xmm0,[0x.......]\n"
       "push eax\n"
       "push eax\n"
       "movsd [esp],xmm0\n"
@@ -2472,8 +2472,8 @@
   double res = reinterpret_cast<PackedDoubleAbsolute>(test->entry())();
   EXPECT_FLOAT_EQ(1.0, res, 0.000001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "andpd xmm0,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "andpd xmm0,[0x.......]\n"
       "push eax\n"
       "push eax\n"
       "movsd [esp],xmm0\n"
@@ -2509,8 +2509,8 @@
   double res = reinterpret_cast<PackedDoubleMul>(test->entry())();
   EXPECT_FLOAT_EQ(9.0, res, 0.000001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "movups xmm1,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "movups xmm1,[0x.......]\n"
       "mulpd xmm0,xmm1\n"
       "push eax\n"
       "push eax\n"
@@ -2547,8 +2547,8 @@
   double res = reinterpret_cast<PackedDoubleDiv>(test->entry())();
   EXPECT_FLOAT_EQ(3.0, res, 0.000001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "movups xmm1,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "movups xmm1,[0x.......]\n"
       "divpd xmm0,xmm1\n"
       "push eax\n"
       "push eax\n"
@@ -2580,7 +2580,7 @@
   double res = reinterpret_cast<PackedDoubleSqrt>(test->entry())();
   EXPECT_FLOAT_EQ(4.0, res, 0.000001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
       "sqrtpd xmm0,xmm0\n"
       "push eax\n"
       "push eax\n"
@@ -2617,8 +2617,8 @@
   double res = reinterpret_cast<PackedDoubleMin>(test->entry())();
   EXPECT_FLOAT_EQ(3.0, res, 0.000001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "movups xmm1,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "movups xmm1,[0x.......]\n"
       "minpd xmm0,xmm1\n"
       "push eax\n"
       "push eax\n"
@@ -2655,8 +2655,8 @@
   double res = reinterpret_cast<PackedDoubleMax>(test->entry())();
   EXPECT_FLOAT_EQ(9.0, res, 0.000001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
-      "movups xmm1,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
+      "movups xmm1,[0x.......]\n"
       "maxpd xmm0,xmm1\n"
       "push eax\n"
       "push eax\n"
@@ -2692,7 +2692,7 @@
   double res = reinterpret_cast<PackedDoubleShuffle>(test->entry())();
   EXPECT_FLOAT_EQ(9.0, res, 0.000001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm0,[rip+0x.......]\n"
+      "movups xmm0,[0x.......]\n"
       "shufpd xmm0, xmm0 [33]\n"
       "shufpd xmm0, xmm0 [0]\n"
       "push eax\n"
@@ -2723,7 +2723,7 @@
   float res = reinterpret_cast<PackedDoubleToSingle>(test->entry())();
   EXPECT_FLOAT_EQ(9.0f, res, 0.000001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm1,[rip+0x.......]\n"
+      "movups xmm1,[0x.......]\n"
       "cvtpd2ps xmm0,xmm1\n"
       "push eax\n"
       "movss [esp],xmm0\n"
@@ -2755,7 +2755,7 @@
   double res = reinterpret_cast<PackedSingleToDouble>(test->entry())();
   EXPECT_FLOAT_EQ(9.0f, res, 0.000001f);
   EXPECT_DISASSEMBLY(
-      "movups xmm1,[rip+0x.......]\n"
+      "movups xmm1,[0x.......]\n"
       "cvtps2pd xmm0,xmm1\n"
       "push eax\n"
       "push eax\n"
@@ -2785,7 +2785,7 @@
   float res = reinterpret_cast<SingleFPOperationsStackCode>(test->entry())(3.4);
   EXPECT_FLOAT_EQ(14.7f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x4144cccd\n"
       "movd xmm0,eax\n"
       "addss xmm0,[esp+0x4]\n"
       "mulss xmm0,[esp+0x4]\n"
@@ -2838,9 +2838,9 @@
   double res = reinterpret_cast<DoubleFPMovesCode>(test->entry())();
   EXPECT_FLOAT_EQ(1024.67, res, 0.0001);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x409002ae\n"
       "push eax\n"
-      "mov eax,0x........\n"
+      "mov eax,0x147ae148\n"
       "push eax\n"
       "movsd xmm0,[esp]\n"
       "movsd xmm1,xmm0\n"
@@ -2891,9 +2891,9 @@
   int64_t res = reinterpret_cast<DoubleFPUStackMovesCode>(test->entry())();
   EXPECT_FLOAT_EQ(1024.67, (bit_cast<double, int64_t>(res)), 0.001);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x409002ae\n"
       "push eax\n"
-      "mov eax,0x........\n"
+      "mov eax,0x147ae148\n"
       "push eax\n"
       "fld_d [esp]\n"
       "mov [esp],0\n"
@@ -2935,16 +2935,16 @@
   double res = reinterpret_cast<DoubleFPOperationsCode>(test->entry())();
   EXPECT_FLOAT_EQ(14.7, res, 0.001);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x40289999\n"
       "push eax\n"
-      "mov eax,0x........\n"
+      "mov eax,0x9999999a\n"
       "push eax\n"
       "movsd xmm0,[esp]\n"
       "pop eax\n"
       "pop eax\n"
-      "mov eax,0x........\n"
+      "mov eax,0x400b3333\n"
       "push eax\n"
-      "mov eax,0x........\n"
+      "mov eax,0x33333333\n"
       "push eax\n"
       "movsd xmm1,[esp]\n"
       "addsd xmm0,xmm1\n"
@@ -2988,9 +2988,9 @@
       reinterpret_cast<DoubleFPOperationsStackCode>(test->entry())(3.4);
   EXPECT_FLOAT_EQ(14.7, res, 0.001);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x40289999\n"
       "push eax\n"
-      "mov eax,0x........\n"
+      "mov eax,0x9999999a\n"
       "push eax\n"
       "movsd xmm0,[esp]\n"
       "pop eax\n"
@@ -3093,8 +3093,8 @@
       reinterpret_cast<NegativeInt64ToDoubleConversionCode>(test->entry())();
   EXPECT_EQ(-6.0, res);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
-      "mov edx,0x........\n"
+      "mov eax,0xffffffff\n"
+      "mov edx,0xfffffffa\n"
       "push eax\n"
       "push edx\n"
       "fild_d [esp]\n"
@@ -3188,7 +3188,7 @@
   double res = reinterpret_cast<FloatToDoubleConversionCode>(test->entry())();
   EXPECT_FLOAT_EQ(12.3, res, 0.001);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x4144cccd\n"
       "movd xmm1,eax\n"
       "xor eax,eax\n"
       "cvtss2sd xmm2,xmm1\n"
@@ -3248,26 +3248,26 @@
   EXPECT_EQ(0, res);
   EXPECT_DISASSEMBLY(
       "xor eax,eax\n"
-      "mov edx,0x........\n"
+      "mov edx,0x4144cccd\n"
       "movd xmm0,edx\n"
-      "mov edx,0x........\n"
+      "mov edx,0x41480000\n"
       "movd xmm1,edx\n"
       "comiss xmm0,xmm1\n"
-      "jpe 0x........\n"
-      "ja 0x........\n"
-      "jc 0x........\n"
+      "jpe +43\n"
+      "ja +40\n"
+      "jc +7\n"
       "inc eax\n"
       "mov edx,0\n"
       "movd xmm1,edx\n"
       "divss xmm1,xmm1\n"
       "comiss xmm1,xmm1\n"
-      "jpe 0x........\n"
+      "jpe +7\n"
       "inc eax\n"
       "ret\n"
       "inc eax\n"
-      "jmp 0x........\n"
+      "jmp -38\n"
       "inc eax\n"
-      "jmp 0x........\n");
+      "jmp -35\n");
 }
 
 ASSEMBLER_TEST_GENERATE(DoubleCompare, assembler) {
@@ -3338,14 +3338,14 @@
   int res = reinterpret_cast<DoubleCompareCode>(test->entry())();
   EXPECT_EQ(0, res);
   EXPECT_DISASSEMBLY(
-      "mov edx,0x........\n"
+      "mov edx,0x40289999\n"
       "push edx\n"
-      "mov edx,0x........\n"
+      "mov edx,0x9999999a\n"
       "push edx\n"
       "movsd xmm0,[esp]\n"
       "pop edx\n"
       "pop edx\n"
-      "mov edx,0x........\n"
+      "mov edx,0x40290000\n"
       "push edx\n"
       "mov edx,0\n"
       "push edx\n"
@@ -3354,9 +3354,9 @@
       "pop edx\n"
       "xor eax,eax\n"
       "comisd xmm0,xmm1\n"
-      "jpe 0x........\n"
-      "ja 0x........\n"
-      "jc 0x........\n"
+      "jpe +54\n"
+      "ja +51\n"
+      "jc +7\n"
       "inc eax\n"
       "mov edx,0\n"
       "push edx\n"
@@ -3367,13 +3367,13 @@
       "pop edx\n"
       "divsd xmm1,xmm1\n"
       "comisd xmm1,xmm1\n"
-      "jpe 0x........\n"
+      "jpe +7\n"
       "inc eax\n"
       "ret\n"
       "inc eax\n"
-      "jmp 0x........\n"
+      "jmp -49\n"
       "inc eax\n"
-      "jmp 0x........\n");
+      "jmp -46\n");
 }
 
 ASSEMBLER_TEST_GENERATE(DoubleToFloatConversion, assembler) {
@@ -3396,9 +3396,9 @@
   float res = reinterpret_cast<DoubleToFloatConversionCode>(test->entry())();
   EXPECT_FLOAT_EQ(12.3f, res, 0.001);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0x40289999\n"
       "push eax\n"
-      "mov eax,0x........\n"
+      "mov eax,0x9999999a\n"
       "push eax\n"
       "movsd xmm0,[esp]\n"
       "cvtsd2ss xmm1,xmm0\n"
@@ -3499,7 +3499,7 @@
   double res = reinterpret_cast<GlobalAddressCode>(test->entry())();
   EXPECT_FLOAT_EQ(kDoubleConst, res, 0.000001);
   EXPECT_DISASSEMBLY(
-      "movsd xmm0,[rip+0x.......]\n"
+      "movsd xmm0,[0x.......]\n"
       "push eax\n"
       "push eax\n"
       "movsd [esp],xmm0\n"
@@ -3703,7 +3703,7 @@
   EXPECT_FLOAT_EQ(-kFloatConst, res, 0.0001);
   EXPECT_DISASSEMBLY(
       "movss xmm0,[esp+0x4]\n"
-      "xorps xmm0,[rip+0x.......]\n"
+      "xorps xmm0,[0x.......]\n"
       "push eax\n"
       "movss [esp],xmm0\n"
       "fld_s [esp]\n"
@@ -3730,7 +3730,7 @@
   EXPECT_FLOAT_EQ(-kDoubleConst, res, 0.0001);
   EXPECT_DISASSEMBLY(
       "movsd xmm0,[esp+0x4]\n"
-      "xorpd xmm0,[rip+0x.......]\n"
+      "xorpd xmm0,[0x.......]\n"
       "push eax\n"
       "push eax\n"
       "movsd [esp],xmm0\n"
@@ -4124,7 +4124,7 @@
       "push eax\n"
       "fnstcw [esp]\n"
       "movzxw eax,[esp]\n"
-      "or eax,0x...\n"
+      "or eax,0xc00\n"
       "movw [esp+0x4],eax\n"
       "fldcw [esp+0x4]\n"
       "push eax\n"
@@ -4214,7 +4214,7 @@
   EXPECT_DISASSEMBLY(
       "movsd xmm0,[esp+0x4]\n"
       "xorpd xmm1,xmm1\n"
-      "xorpd xmm1,[rip+0x.......]\n"
+      "xorpd xmm1,[0x.......]\n"
       "orpd xmm0,xmm1\n"
       "push eax\n"
       "push eax\n"
@@ -4383,7 +4383,7 @@
   EXPECT_FLOAT_EQ(val, res, 0.001);
   EXPECT_DISASSEMBLY(
       "movsd xmm0,[esp+0x4]\n"
-      "andpd xmm0,[rip+0x.......]\n"
+      "andpd xmm0,[0x.......]\n"
       "push eax\n"
       "push eax\n"
       "movsd [esp],xmm0\n"
@@ -4445,7 +4445,7 @@
       "mov edx,[esp+0x8]\n"
       "xor eax,eax\n"
       "mov ebx,1\n"
-      "mov ecx,0x........\n"
+      "mov ecx,0xffffffff\n"
       "test edx,edx\n"
       "cmovs eax,ecx\n"
       "test edx,edx\n"
@@ -4500,7 +4500,7 @@
       "xor eax,eax\n"
       "mov ecx,1\n"
       "mov edx,[esp+0x4]\n"
-      "cmp edx,0x...\n"
+      "cmp edx,0x311\n"
       "cmovz eax,ecx\n"
       "ret\n");
 }
@@ -4525,7 +4525,7 @@
       "xor eax,eax\n"
       "mov ecx,1\n"
       "mov edx,[esp+0x4]\n"
-      "cmp edx,0x...\n"
+      "cmp edx,0x311\n"
       "cmovnz eax,ecx\n"
       "ret\n");
 }
@@ -4550,7 +4550,7 @@
   EXPECT_EQ(-1, res);  // Less.
   EXPECT_DISASSEMBLY(
       "mov edx,1\n"
-      "mov ecx,0x........\n"
+      "mov ecx,0xffffffff\n"
       "mov eax,[esp+0x4]\n"
       "cmp eax,[esp+0x8]\n"
       "cmovl eax,ecx\n"
@@ -4574,8 +4574,8 @@
   double res = reinterpret_cast<TestLoadDoubleConstantCode>(test->entry())();
   EXPECT_FLOAT_EQ(-12.34, res, 0.0001);
   EXPECT_DISASSEMBLY(
-      "push 0x........\n"
-      "push 0x........\n"
+      "push 0xc028ae14\n"
+      "push 0x7ae147ae\n"
       "movsd xmm3,[esp]\n"
       "add esp,8\n"
       "push eax\n"
@@ -4608,17 +4608,7 @@
   typedef bool (*TestObjectCompare)();
   bool res = reinterpret_cast<TestObjectCompare>(test->entry())();
   EXPECT_EQ(true, res);
-  EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
-      "cmp eax,0x........\n"
-      "jnz 0x........\n"
-      "mov ecx,0x........\n"
-      "cmp ecx,0x........\n"
-      "jnz 0x........\n"
-      "mov eax,1\n"
-      "ret\n"
-      "mov eax,0\n"
-      "ret\n");
+  // Disassembly contains absolute addresses of objects that vary between runs.
 }
 
 ASSEMBLER_TEST_GENERATE(TestSetCC, assembler) {
@@ -4633,7 +4623,7 @@
   uword res = reinterpret_cast<TestSetCC>(test->entry())();
   EXPECT_EQ(0xFFFFFF00, res);
   EXPECT_DISASSEMBLY(
-      "mov eax,0x........\n"
+      "mov eax,0xffffffff\n"
       "cmp eax,eax\n"
       "setnz eax\n"
       "ret\n");
@@ -4900,7 +4890,7 @@
       "mov eax,4\n"
       "mov ecx,2\n"
       "bt eax,ecx\n"
-      "jc 0x........\n"
+      "jc +7\n"
       "int3\n"
       "mov eax,1\n"
       "ret\n");
@@ -4923,7 +4913,7 @@
   EXPECT_DISASSEMBLY(
       "mov ecx,0x20\n"
       "bt ecx,5\n"
-      "jc 0x........\n"
+      "jc +7\n"
       "int3\n"
       "mov eax,1\n"
       "ret\n");
diff --git a/runtime/vm/compiler/assembler/assembler_x64_test.cc b/runtime/vm/compiler/assembler/assembler_x64_test.cc
index 3d2deb2..1dded0f 100644
--- a/runtime/vm/compiler/assembler/assembler_x64_test.cc
+++ b/runtime/vm/compiler/assembler/assembler_x64_test.cc
@@ -24,9 +24,9 @@
 #define EXPECT_DISASSEMBLY_NOT_WINDOWS_ENDS_WITH(expected)
 #else
 #define EXPECT_DISASSEMBLY(expected)                                           \
-  EXPECT_STREQ(expected, test->BlankedDisassembly())
+  EXPECT_STREQ(expected, test->RelativeDisassembly())
 #define EXPECT_DISASSEMBLY_ENDS_WITH(expected_arg)                             \
-  char* disassembly = test->BlankedDisassembly();                              \
+  char* disassembly = test->RelativeDisassembly();                             \
   const char* expected = expected_arg;                                         \
   intptr_t dis_len = strlen(disassembly);                                      \
   intptr_t exp_len = strlen(expected);                                         \
@@ -279,18 +279,18 @@
       "movq rax,[r10-0x8]\n"
       "movq rax,[r12-0x8]\n"
       "movq rax,[r13-0x8]\n"
-      "movq rax,[rsp+0x...]\n"
-      "movq rax,[rbp+0x...]\n"
-      "movq rax,[rax+0x...]\n"
-      "movq rax,[r10+0x...]\n"
-      "movq rax,[r12+0x...]\n"
-      "movq rax,[r13+0x...]\n"
-      "movq rax,[rsp-0x...]\n"
-      "movq rax,[rbp-0x...]\n"
-      "movq rax,[rax-0x...]\n"
-      "movq rax,[r10-0x...]\n"
-      "movq rax,[r12-0x...]\n"
-      "movq rax,[r13-0x...]\n"
+      "movq rax,[rsp+0x800]\n"
+      "movq rax,[rbp+0x800]\n"
+      "movq rax,[rax+0x800]\n"
+      "movq rax,[r10+0x800]\n"
+      "movq rax,[r12+0x800]\n"
+      "movq rax,[r13+0x800]\n"
+      "movq rax,[rsp-0x800]\n"
+      "movq rax,[rbp-0x800]\n"
+      "movq rax,[rax-0x800]\n"
+      "movq rax,[r10-0x800]\n"
+      "movq rax,[r12-0x800]\n"
+      "movq rax,[r13-0x800]\n"
       "movq rax,[rax*1+0]\n"
       "movq rax,[rax*2+0]\n"
       "movq rax,[rax*4+0]\n"
@@ -305,11 +305,11 @@
       "movq rax,[r10*2+0x8]\n"
       "movq rax,[r12*2+0x8]\n"
       "movq rax,[r13*2+0x8]\n"
-      "movq rax,[rbp*2+0x...]\n"
-      "movq rax,[rax*2+0x...]\n"
-      "movq rax,[r10*2+0x...]\n"
-      "movq rax,[r12*2+0x...]\n"
-      "movq rax,[r13*2+0x...]\n"
+      "movq rax,[rbp*2+0x800]\n"
+      "movq rax,[rax*2+0x800]\n"
+      "movq rax,[r10*2+0x800]\n"
+      "movq rax,[r12*2+0x800]\n"
+      "movq rax,[r13*2+0x800]\n"
       "movq rax,[rax+rbp*2]\n"
       "movq rax,[rax+rax*2]\n"
       "movq rax,[rax+r10*2]\n"
@@ -370,36 +370,36 @@
       "movq rax,[r13+r10*2+0x8]\n"
       "movq rax,[r13+r12*2+0x8]\n"
       "movq rax,[r13+r13*2+0x8]\n"
-      "movq rax,[rax+rbp*2+0x...]\n"
-      "movq rax,[rax+rax*2+0x...]\n"
-      "movq rax,[rax+r10*2+0x...]\n"
-      "movq rax,[rax+r12*2+0x...]\n"
-      "movq rax,[rax+r13*2+0x...]\n"
-      "movq rax,[rbp+rbp*2+0x...]\n"
-      "movq rax,[rbp+rax*2+0x...]\n"
-      "movq rax,[rbp+r10*2+0x...]\n"
-      "movq rax,[rbp+r12*2+0x...]\n"
-      "movq rax,[rbp+r13*2+0x...]\n"
-      "movq rax,[rsp+rbp*2+0x...]\n"
-      "movq rax,[rsp+rax*2+0x...]\n"
-      "movq rax,[rsp+r10*2+0x...]\n"
-      "movq rax,[rsp+r12*2+0x...]\n"
-      "movq rax,[rsp+r13*2+0x...]\n"
-      "movq rax,[r10+rbp*2+0x...]\n"
-      "movq rax,[r10+rax*2+0x...]\n"
-      "movq rax,[r10+r10*2+0x...]\n"
-      "movq rax,[r10+r12*2+0x...]\n"
-      "movq rax,[r10+r13*2+0x...]\n"
-      "movq rax,[r12+rbp*2+0x...]\n"
-      "movq rax,[r12+rax*2+0x...]\n"
-      "movq rax,[r12+r10*2+0x...]\n"
-      "movq rax,[r12+r12*2+0x...]\n"
-      "movq rax,[r12+r13*2+0x...]\n"
-      "movq rax,[r13+rbp*2+0x...]\n"
-      "movq rax,[r13+rax*2+0x...]\n"
-      "movq rax,[r13+r10*2+0x...]\n"
-      "movq rax,[r13+r12*2+0x...]\n"
-      "movq rax,[r13+r13*2+0x...]\n"
+      "movq rax,[rax+rbp*2+0x800]\n"
+      "movq rax,[rax+rax*2+0x800]\n"
+      "movq rax,[rax+r10*2+0x800]\n"
+      "movq rax,[rax+r12*2+0x800]\n"
+      "movq rax,[rax+r13*2+0x800]\n"
+      "movq rax,[rbp+rbp*2+0x800]\n"
+      "movq rax,[rbp+rax*2+0x800]\n"
+      "movq rax,[rbp+r10*2+0x800]\n"
+      "movq rax,[rbp+r12*2+0x800]\n"
+      "movq rax,[rbp+r13*2+0x800]\n"
+      "movq rax,[rsp+rbp*2+0x800]\n"
+      "movq rax,[rsp+rax*2+0x800]\n"
+      "movq rax,[rsp+r10*2+0x800]\n"
+      "movq rax,[rsp+r12*2+0x800]\n"
+      "movq rax,[rsp+r13*2+0x800]\n"
+      "movq rax,[r10+rbp*2+0x800]\n"
+      "movq rax,[r10+rax*2+0x800]\n"
+      "movq rax,[r10+r10*2+0x800]\n"
+      "movq rax,[r10+r12*2+0x800]\n"
+      "movq rax,[r10+r13*2+0x800]\n"
+      "movq rax,[r12+rbp*2+0x800]\n"
+      "movq rax,[r12+rax*2+0x800]\n"
+      "movq rax,[r12+r10*2+0x800]\n"
+      "movq rax,[r12+r12*2+0x800]\n"
+      "movq rax,[r12+r13*2+0x800]\n"
+      "movq rax,[r13+rbp*2+0x800]\n"
+      "movq rax,[r13+rax*2+0x800]\n"
+      "movq rax,[r13+r10*2+0x800]\n"
+      "movq rax,[r13+r12*2+0x800]\n"
+      "movq rax,[r13+r13*2+0x800]\n"
       "movq rax,[rsp+0]\n"
       "movq rax,[rbp+0]\n"
       "movq rax,[rax+0]\n"
@@ -446,23 +446,23 @@
   typedef void (*JumpAroundCrashCode)();
   reinterpret_cast<JumpAroundCrashCode>(test->entry())();
   EXPECT_DISASSEMBLY(
-      "jo 0x................\n"
-      "jno 0x................\n"
-      "jc 0x................\n"
-      "jnc 0x................\n"
-      "jz 0x................\n"
-      "jnz 0x................\n"
-      "jna 0x................\n"
-      "ja 0x................\n"
-      "js 0x................\n"
-      "jns 0x................\n"
-      "jpe 0x................\n"
-      "jpo 0x................\n"
-      "jl 0x................\n"
-      "jge 0x................\n"
-      "jle 0x................\n"
-      "jg 0x................\n"
-      "jmp 0x................\n"
+      "jo +109\n"
+      "jno +103\n"
+      "jc +97\n"
+      "jnc +91\n"
+      "jz +85\n"
+      "jnz +79\n"
+      "jna +73\n"
+      "ja +67\n"
+      "js +61\n"
+      "jns +55\n"
+      "jpe +49\n"
+      "jpo +43\n"
+      "jl +37\n"
+      "jge +31\n"
+      "jle +25\n"
+      "jg +19\n"
+      "jmp +13\n"
       "movl rax,0\n"
       "movq [rax],rax\n"
       "ret\n");
@@ -489,7 +489,7 @@
       "addq rax,2\n"
       "incq rcx\n"
       "cmpq rcx,0x57\n"
-      "jl 0x................\n"
+      "jl -11\n"
       "ret\n");
 }
 
@@ -510,10 +510,10 @@
   EXPECT_EQ(1, reinterpret_cast<CmpbCode>(test->entry())());
   EXPECT_DISASSEMBLY(
       "movl rax,1\n"
-      "movl r11,0x........\n"
+      "movl r11,0xffffff11\n"
       "push r11\n"
       "cmpb [rsp],0x11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "movl rax,0\n"
       "pop rcx\n"
       "ret\n");
@@ -542,12 +542,12 @@
   EXPECT_DISASSEMBLY(
       "movl rax,1\n"
       "movl rcx,0\n"
-      "movl r11,0x........\n"
+      "movl r11,0xffffff11\n"
       "push r11\n"
       "testb [rsp],0x10\n"
       "cmovzq rax,rcx\n"
       "testb [rsp],0x20\n"
-      "jz 0x................\n"
+      "jz +11\n"
       "movl rax,0\n"
       "pop rcx\n"
       "ret\n");
@@ -610,43 +610,43 @@
   typedef int64_t (*Testb2Code)();
   EXPECT_EQ(42, reinterpret_cast<Testb2Code>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0xffffefff\n"
       "bsrq rcx,rax\n"
       "cmpq rcx,0x1f\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
 
       "sarq rax,1\n"
-      "cmpq rax,0x........\n"
-      "jz 0x................\n"
+      "cmpq rax,0x7ffff7ff\n"
+      "jz +7\n"
       "int3\n"
 
-      "movl rax,0x........\n"
+      "movl rax,0x7fffffff\n"
       "bsrq rcx,rax\n"
       "cmpq rcx,0x1e\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
 
-      "cmpq rax,0x........\n"
-      "jz 0x................\n"
+      "cmpq rax,0x7fffffff\n"
+      "jz +7\n"
       "int3\n"
 
-      "movq rax,0x................\n"
-      "andl rax,0x........\n"
-      "cmpq rax,0x........\n"
-      "jz 0x................\n"
+      "movq rax,0x0000000101020408\n"
+      "andl rax,0xffffffff\n"
+      "cmpq rax,0x01020408\n"
+      "jz +7\n"
       "int3\n"
 
-      "movq rcx,0x................\n"
-      "andl rcx,0x........\n"
-      "cmpq rcx,0x........\n"
-      "jz 0x................\n"
+      "movq rcx,0x0000000101020408\n"
+      "andl rcx,0xffffffff\n"
+      "cmpq rcx,0x01020408\n"
+      "jz +7\n"
       "int3\n"
 
-      "movl rax,0x........\n"
+      "movl rax,0x0fffeff0\n"
       "bsfq rcx,rax\n"
       "cmpq rcx,4\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
 
       "movl rax,0x2a\n"
@@ -676,7 +676,7 @@
       "push rdi\n"
       "movl rdx,0x10\n"
       "testb rdx,[rsp]\n"
-      "jz 0x................\n"
+      "jz +13\n"
       "movl rax,1\n"
       "pop rcx\n"
       "ret\n"
@@ -725,7 +725,7 @@
   typedef int64_t (*LzcntCode)();
   EXPECT_EQ(108, reinterpret_cast<LzcntCode>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movl rcx,0x...\n"
+      "movl rcx,0xf00\n"
       "lzcntq rax,rcx\n"
       "movl rcx,0xf0\n"
       "lzcntq rcx,rcx\n"
@@ -818,7 +818,7 @@
   typedef int64_t (*IncrementCodeLong)();
   EXPECT_EQ(0x100000001, reinterpret_cast<IncrementCodeLong>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0xffffffff\n"
       "push rax\n"
       "incq [rsp]\n"
       "movq rcx,[rsp]\n"
@@ -870,7 +870,7 @@
   typedef int64_t (*DecrementCodeLong)();
   EXPECT_EQ(0xffffffff, reinterpret_cast<DecrementCodeLong>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movq rax,0x................\n"
+      "movq rax,0x0000000100000001\n"
       "push rax\n"
       "decq [rsp]\n"
       "movq rcx,[rsp]\n"
@@ -895,7 +895,7 @@
       "movl rax,2\n"
       "movl rcx,4\n"
       "imull rax,rcx\n"
-      "imull rax,rax,0x...\n"
+      "imull rax,rax,0x3e8\n"
       "ret\n");
 }
 
@@ -1009,13 +1009,13 @@
   EXPECT_EQ(kProductLargeConstants,
             reinterpret_cast<SignedMultiplyLong>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movq rax,0x................\n"
-      "movq rcx,0x................\n"
+      "movq rax,0x1234567887654321\n"
+      "movq rcx,0x0db4da5f7ef412b1\n"
       "imulq rax,rcx\n"
-      "movq r11,0x................\n"
+      "movq r11,0x1234567887654321\n"
       "imulq rcx,r11\n"
       "cmpq rax,rcx\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "ret\n");
 }
@@ -1034,8 +1034,8 @@
   EXPECT_EQ(0, reinterpret_cast<OverflowSignedMultiply>(test->entry())());
   EXPECT_DISASSEMBLY(
       "movl rdx,0\n"
-      "movl rax,0x........\n"
-      "movl rcx,0x........\n"
+      "movl rax,0x0fffffff\n"
+      "movl rcx,0x0fffffff\n"
       "imull rax,rcx\n"
       "imull rax,rdx\n"
       "ret\n");
@@ -1057,7 +1057,7 @@
       "movl rdx,2\n"
       "movl rcx,4\n"
       "imull rdx,rcx\n"
-      "imull rdx,rdx,0x...\n"
+      "imull rdx,rdx,0x3e8\n"
       "movl rax,rdx\n"
       "ret\n");
 }
@@ -1077,7 +1077,7 @@
   EXPECT_DISASSEMBLY(
       "push pp\n"
       "movl pp,2\n"
-      "imull pp,pp,0x...\n"
+      "imull pp,pp,0x3e8\n"
       "movl rax,pp\n"
       "pop pp\n"
       "ret\n");
@@ -1115,7 +1115,7 @@
   typedef int32_t (*SignedDivide)();
   EXPECT_EQ(-87 / 42, reinterpret_cast<SignedDivide>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movl rax,-0x........\n"
+      "movl rax,-0x00000057\n"
       "movl rdx,0x7b\n"
       "cdq\n"
       "movl rcx,0x2a\n"
@@ -1140,7 +1140,7 @@
   EXPECT_EQ(0xf0000000, reinterpret_cast<UnsignedDivide>(test->entry())());
   EXPECT_DISASSEMBLY(
       "movl rax,0\n"
-      "movl rdx,-0x........\n"
+      "movl rdx,-0x10000000\n"
       "movl rcx,-1\n"
       "divl (rax,rdx),rcx\n"
       "ret\n");
@@ -1160,7 +1160,7 @@
   EXPECT_EQ(kLargeConstant / 42,
             reinterpret_cast<SignedDivideLong>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movq rax,0x................\n"
+      "movq rax,0x1234567887654321\n"
       "movl rdx,0x7b\n"
       "cqo\n"
       "movl rcx,0x2a\n"
@@ -1187,7 +1187,7 @@
             reinterpret_cast<UnsignedDivideLong>(test->entry())());
   EXPECT_DISASSEMBLY(
       "movl rax,0\n"
-      "movq rdx,0x................\n"
+      "movq rdx,0xf000000000000000\n"
       "movq rcx,-1\n"
       "divq (rax,rdx),rcx\n"
       "ret\n");
@@ -1232,7 +1232,7 @@
   EXPECT_DISASSEMBLY_NOT_WINDOWS(
       "push rdi\n"
       "movq rcx,[rsp]\n"
-      "movl rax,0x...\n"
+      "movl rax,0x29a\n"
       "bsrq rax,rcx\n"
       "pop rcx\n"
       "ret\n");
@@ -1252,7 +1252,7 @@
   typedef int (*MoveExtend)();
   EXPECT_EQ(0xff - 1 + 0xffff, reinterpret_cast<MoveExtend>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movl rdx,0x....\n"
+      "movl rdx,0xffff\n"
       "movzxbq rax,rdx\n"
       "movsxwq r8,rdx\n"
       "movzxwq rcx,rdx\n"
@@ -1274,9 +1274,9 @@
   typedef intptr_t (*MoveExtend)();
   EXPECT_EQ(0x7ffffffe, reinterpret_cast<MoveExtend>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movl rdx,0x........\n"
+      "movl rdx,0xffffffff\n"
       "movsxdq rdx,rdx\n"
-      "movl rax,0x........\n"
+      "movl rax,0x7fffffff\n"
       "movsxdq rax,rax\n"
       "addq rax,rdx\n"
       "ret\n");
@@ -1301,7 +1301,7 @@
   EXPECT_EQ(0xff - 1 + 0xffff,
             reinterpret_cast<MoveExtendMemory>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movq rdx,0x................\n"
+      "movq rdx,0x123456781234ffff\n"
       "push rdx\n"
       "movzxbq rax,[rsp]\n"
       "movsxwq r8,[rsp]\n"
@@ -1327,9 +1327,9 @@
   typedef intptr_t (*MoveExtend)();
   EXPECT_EQ(0x7ffffffe, reinterpret_cast<MoveExtend>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movl r11,0x........\n"
+      "movl r11,0xffffffff\n"
       "push r11\n"
-      "push 0x........\n"
+      "push 0x7fffffff\n"
       "movsxdq rdx,[rsp+0x8]\n"
       "movsxdq rax,[rsp]\n"
       "addq rsp,0x10\n"
@@ -1378,12 +1378,12 @@
   typedef int64_t (*WordOps)();
   EXPECT_EQ(0x0100010503050507, reinterpret_cast<WordOps>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movq rax,0x................\n"
+      "movq rax,0x0102030405060708\n"
       "push rax\n"
-      "addw [rsp],0x....\n"
-      "subw [rsp+0x2],0x...\n"
-      "xorw [rsp+0x4],0x...\n"
-      "andw [rsp+0x6],0x...\n"
+      "addw [rsp],0xfdff\n"
+      "subw [rsp+0x2],0x201\n"
+      "xorw [rsp+0x4],0x201\n"
+      "andw [rsp+0x6],0x301\n"
       "andw [rsp],-1\n"
       "pop rax\n"
       "ret\n");
@@ -1405,7 +1405,7 @@
   typedef int64_t (*ByteOps)();
   EXPECT_EQ(0x0100030505050707, reinterpret_cast<ByteOps>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movq rax,0x................\n"
+      "movq rax,0x0102030405060708\n"
       "push rax\n"
       "addb [rsp],-1\n"
       "subb [rsp+0x2],1\n"
@@ -1904,10 +1904,10 @@
       "orl [rsi],r10\n"
       "movl rcx,0x2a\n"
       "xorl rcx,rcx\n"
-      "orl rcx,0x...\n"
+      "orl rcx,0x100\n"
       "movl rax,4\n"
       "orl rcx,rax\n"
-      "movl rax,0x....\n"
+      "movl rax,0xfff0\n"
       "andl rcx,rax\n"
       "movl rax,1\n"
       "orl rcx,rax\n"
@@ -1961,23 +1961,23 @@
       "xorq rax,[rsp]\n"
       "pop rcx\n"
       "cmpq rax,0\n"
-      "jnz 0x................\n"
+      "jnz +105\n"
       "movl rcx,0xff\n"
       "movl rax,5\n"
       "xorq rcx,rax\n"
       "cmpq rcx,0xfa\n"
-      "jnz 0x................\n"
+      "jnz +79\n"
       "push 0xff\n"
       "movl rcx,5\n"
       "xorq [rsp],rcx\n"
       "pop rcx\n"
       "cmpq rcx,0xfa\n"
-      "jnz 0x................\n"
+      "jnz +51\n"
       "xorq rcx,rcx\n"
-      "orq rcx,0x...\n"
+      "orq rcx,0x100\n"
       "movl rax,4\n"
       "orq rcx,rax\n"
-      "movl rax,0x....\n"
+      "movl rax,0xfff0\n"
       "andq rcx,rax\n"
       "movl rax,1\n"
       "push rax\n"
@@ -2263,155 +2263,155 @@
       "movl rax,4\n"
       "andl rax,2\n"
       "cmpl rax,0\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rcx,4\n"
       "andl rcx,4\n"
       "cmpl rcx,0\n"
-      "jnz 0x................\n"
+      "jnz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,0\n"
       "orl rax,0\n"
       "cmpl rax,0\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,4\n"
       "orl rax,0\n"
       "cmpl rax,0\n"
-      "jnz 0x................\n"
+      "jnz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "push rax\n"
       "movl rax,0xff\n"
       "movl [rsp],rax\n"
       "cmpl [rsp],0xff\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movq [rax],rax\n"
       "pop rax\n"
       "movl rax,1\n"
       "shll rax,3\n"
       "cmpl rax,8\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,2\n"
       "shrl rax,1\n"
       "cmpl rax,1\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,8\n"
       "shrl rax,3\n"
       "cmpl rax,1\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,1\n"
       "movl rcx,3\n"
       "shll rax,cl\n"
       "cmpl rax,8\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,8\n"
       "movl rcx,3\n"
       "shrl rax,cl\n"
       "cmpl rax,1\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,1\n"
       "shlq rax,3\n"
       "cmpl rax,8\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,2\n"
       "shrq rax,1\n"
       "cmpl rax,1\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,8\n"
       "shrq rax,3\n"
       "cmpl rax,1\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,1\n"
       "movl rcx,3\n"
       "shlq rax,cl\n"
       "cmpl rax,8\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,8\n"
       "movl rcx,3\n"
       "shrq rax,cl\n"
       "cmpl rax,1\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,1\n"
       "shlq rax,31\n"
       "shrq rax,3\n"
-      "cmpq rax,0x........\n"
-      "jz 0x................\n"
+      "cmpq rax,0x10000000\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,1\n"
       "shlq rax,31\n"
       "sarl rax,3\n"
-      "cmpl rax,0x........\n"
-      "jz 0x................\n"
+      "cmpl rax,0xf0000000\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,1\n"
       "movl rcx,3\n"
       "shlq rax,31\n"
       "sarl rax,cl\n"
-      "cmpl rax,0x........\n"
-      "jz 0x................\n"
+      "cmpl rax,0xf0000000\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
-      "movl rdx,-0x........\n"
+      "movl rdx,-0x01000000\n"
       "movl r8,-1\n"
       "movl rcx,2\n"
       "shll rdx,cl\n"
       "shldl rdx,r8,2\n"
-      "cmpl rdx,0x........\n"
-      "jz 0x................\n"
+      "cmpl rdx,0xf0000003\n"
+      "jz +7\n"
       "int3\n"
-      "movq rdx,0x................\n"
+      "movq rdx,0xff00000000000000\n"
       "movq r8,-1\n"
       "movl rcx,2\n"
       "shlq rdx,cl\n"
       "shldq rdx,r8,2\n"
-      "movq r11,0x................\n"
+      "movq r11,0xf000000000000003\n"
       "cmpq rdx,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
-      "movq rdx,0x................\n"
+      "movq rdx,0xff00000000000000\n"
       "movq r8,-1\n"
       "movl rcx,2\n"
       "shlq rdx,cl\n"
       "shldq rdx,r8,cl\n"
-      "movq r11,0x................\n"
+      "movq r11,0xf000000000000003\n"
       "cmpq rdx,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
-      "movq rdx,0x................\n"
+      "movq rdx,0xff00000000000000\n"
       "movq r8,-1\n"
       "movl rcx,2\n"
       "shrq rdx,cl\n"
       "shrdq rdx,r8,cl\n"
-      "movq r11,0x................\n"
+      "movq r11,0xcff0000000000000\n"
       "cmpq rdx,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "movl rax,0\n"
       "ret\n");
@@ -2607,126 +2607,126 @@
       "movl rax,4\n"
       "andl rax,2\n"
       "cmpq rax,0\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "movl rcx,4\n"
       "push rcx\n"
       "andq rcx,[rsp]\n"
       "pop rax\n"
       "cmpq rcx,0\n"
-      "jnz 0x................\n"
+      "jnz +7\n"
       "int3\n"
       "movl rax,0\n"
       "orq rax,0\n"
       "cmpq rax,0\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "movl rax,4\n"
       "orq rax,0\n"
       "cmpq rax,0\n"
-      "jnz 0x................\n"
+      "jnz +7\n"
       "int3\n"
       "push rax\n"
       "movl rax,0xff\n"
       "movq [rsp],rax\n"
       "cmpq [rsp],0xff\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "pop rax\n"
       "movl rax,1\n"
       "shlq rax,3\n"
       "cmpq rax,8\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "movl rax,2\n"
       "shrq rax,1\n"
       "cmpq rax,1\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "movl rax,8\n"
       "shrq rax,3\n"
       "cmpq rax,1\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "movl rax,1\n"
       "movl rcx,3\n"
       "shlq rax,cl\n"
       "cmpq rax,8\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "movl rax,8\n"
       "movl rcx,3\n"
       "shrq rax,cl\n"
       "cmpq rax,1\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "movl rax,1\n"
       "shlq rax,3\n"
       "cmpq rax,8\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movq [rax],rax\n"
       "movl rax,2\n"
       "shrq rax,1\n"
       "cmpq rax,1\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "movl rax,8\n"
       "shrq rax,3\n"
       "cmpq rax,1\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "movl rax,1\n"
       "movl rcx,3\n"
       "shlq rax,cl\n"
       "cmpq rax,8\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "movl rax,8\n"
       "movl rcx,3\n"
       "shrq rax,cl\n"
       "cmpq rax,1\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "movl rax,1\n"
       "shlq rax,31\n"
       "shrq rax,3\n"
-      "cmpq rax,0x........\n"
-      "jz 0x................\n"
+      "cmpq rax,0x10000000\n"
+      "jz +7\n"
       "int3\n"
       "movl rax,1\n"
       "shlq rax,63\n"
       "sarq rax,3\n"
-      "movq r11,0x................\n"
+      "movq r11,0xf000000000000000\n"
       "cmpq rax,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "movl rax,1\n"
       "movl rcx,3\n"
       "shlq rax,63\n"
       "sarq rax,cl\n"
-      "movq r11,0x................\n"
+      "movq r11,0xf000000000000000\n"
       "cmpq rax,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "push pp\n"
-      "movq pp,0x................\n"
+      "movq pp,0xf000000000000001\n"
       "andq pp,-1\n"
-      "movq r11,0x................\n"
+      "movq r11,0x8000000000000001\n"
       "andq pp,r11\n"
       "orq pp,2\n"
-      "movq r11,0x................\n"
+      "movq r11,0xf800000000000000\n"
       "orq pp,r11\n"
       "xorq pp,1\n"
-      "movq r11,0x................\n"
+      "movq r11,0x0800000000000000\n"
       "xorq pp,r11\n"
-      "movq r11,0x................\n"
+      "movq r11,0xf000000000000002\n"
       "cmpq pp,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "andl pp,2\n"
       "cmpq pp,2\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "pop pp\n"
       "movl rax,0\n"
@@ -2783,23 +2783,23 @@
       "movl rax,4\n"
       "movl rcx,2\n"
       "testl rax,rcx\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rdx,4\n"
       "movl rcx,4\n"
       "testl rdx,rcx\n"
-      "jnz 0x................\n"
+      "jnz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,0\n"
       "test al,0\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rcx,4\n"
       "testb rcx,4\n"
-      "jnz 0x................\n"
+      "jnz +14\n"
       "movl rax,0\n"
       "movl [rax],rax\n"
       "movl rax,0\n"
@@ -2874,33 +2874,33 @@
       "movl rax,4\n"
       "movl rcx,2\n"
       "testq rax,rcx\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movq [rax],rax\n"
       "movl rdx,4\n"
       "movl rcx,4\n"
       "testq rdx,rcx\n"
-      "jnz 0x................\n"
+      "jnz +14\n"
       "movl rax,0\n"
       "movq [rax],rax\n"
       "movl rax,0\n"
       "test al,0\n"
-      "jz 0x................\n"
+      "jz +14\n"
       "movl rax,0\n"
       "movq [rax],rax\n"
       "movl rcx,4\n"
       "testb rcx,4\n"
-      "jnz 0x................\n"
+      "jnz +14\n"
       "movl rax,0\n"
       "movq [rax],rax\n"
       "movl rcx,0xff\n"
       "testb rcx,0xff\n"
-      "jnz 0x................\n"
+      "jnz +14\n"
       "movl rax,0\n"
       "movq [rax],rax\n"
       "movl rax,0xff\n"
       "test al,0xff\n"
-      "jnz 0x................\n"
+      "jnz +14\n"
       "movl rax,0\n"
       "movq [rax],rax\n"
       "movl rax,0\n"
@@ -2976,7 +2976,7 @@
   EXPECT_EQ(0x100000000,
             reinterpret_cast<CompareSwapEQ32Code>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movq rax,0x................\n"
+      "movq rax,0x0000000100000000\n"
       "push rax\n"
       "movl rax,4\n"
       "movl rcx,0\n"
@@ -3002,7 +3002,7 @@
   EXPECT_EQ(0x100000004l,
             reinterpret_cast<CompareSwapNEQ32Code>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movq rax,0x................\n"
+      "movq rax,0x0000000100000000\n"
       "push rax\n"
       "movl rax,2\n"
       "movl rcx,4\n"
@@ -3025,8 +3025,8 @@
   EXPECT_EQ(kAnotherLargeConstant - kLargeConstant,
             reinterpret_cast<Exchange>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movq rax,0x................\n"
-      "movq rdx,0x................\n"
+      "movq rax,0x1234567887654321\n"
+      "movq rdx,0x0db4da5f7ef412b1\n"
       "xchgq rax,rdx\n"
       "subq rax,rdx\n"
       "ret\n");
@@ -3042,7 +3042,7 @@
   EXPECT_EQ(kLargeConstant,
             reinterpret_cast<LargeConstantCode>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movq rax,0x................\n"
+      "movq rax,0x1234567887654321\n"
       "ret\n");
 }
 
@@ -3173,7 +3173,7 @@
   typedef float (*SingleFPMovesCode)();
   EXPECT_EQ(234, reinterpret_cast<SingleFPMovesCode>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0x436a0000\n"
       "movd xmm0,rax\n"
       "movss rcx,xmm0\n"
       "movss rdx,xmm1\n"
@@ -3249,7 +3249,7 @@
   typedef float (*SingleFPMoves2Code)();
   EXPECT_EQ(234, reinterpret_cast<SingleFPMoves2Code>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0x436a0000\n"
       "movd xmm0,rax\n"
       "movd xmm8,rax\n"
       "movss rcx,xmm8\n"
@@ -3280,7 +3280,7 @@
   EXPECT_EQ((bit_cast<uint64_t, double>(234.5f)),
             reinterpret_cast<MovqXmmToCpuCode>(test->entry())());
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0x436a8000\n"
       "movd xmm0,rax\n"
       "cvtss2sd xmm0,xmm0\n"
       "movq rax,xmm0\n"
@@ -3384,7 +3384,7 @@
   EXPECT_FLOAT_EQ(-1.0, res, 0.000001f);
   EXPECT_DISASSEMBLY_NOT_WINDOWS_ENDS_WITH(
       "movups xmm10,[rax]\n"
-      "movq r11,[thr+0x...]\n"
+      "movq r11,[thr+0x2b0]\n"
       "xorpd xmm10,[r11]\n"
       "movaps xmm0,xmm10\n"
       "pop thr\n"
@@ -3413,7 +3413,7 @@
   EXPECT_FLOAT_EQ(1.0, res, 0.000001f);
   EXPECT_DISASSEMBLY_NOT_WINDOWS_ENDS_WITH(
       "movups xmm10,[rax]\n"
-      "movq r11,[thr+0x...]\n"
+      "movq r11,[thr+0x2b8]\n"
       "movups xmm0,[r11]\n"
       "andpd xmm0,xmm10\n"
       "pop thr\n"
@@ -3669,10 +3669,10 @@
   EXPECT_DISASSEMBLY(
       "push rbx\n"
       "push rcx\n"
-      "movl rbx,0x........\n"
+      "movl rbx,0x4144cccd\n"
       "movd xmm0,rbx\n"
       "movd xmm8,rbx\n"
-      "movl rcx,0x........\n"
+      "movl rcx,0x4059999a\n"
       "movd xmm1,rcx\n"
       "movd xmm9,rcx\n"
       "addss xmm0,xmm1\n"
@@ -3710,10 +3710,10 @@
   float res = reinterpret_cast<PackedFPOperationsCode>(test->entry())();
   EXPECT_FLOAT_EQ(14.7f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0x4144cccd\n"
       "movd xmm10,rax\n"
       "shufps xmm10,xmm10 [0]\n"
-      "movl rax,0x........\n"
+      "movl rax,0x4059999a\n"
       "movd xmm9,rax\n"
       "shufps xmm9,xmm9 [0]\n"
       "addps xmm10,xmm9\n"
@@ -3829,7 +3829,7 @@
   float res = reinterpret_cast<PackedFPOperations2Code>(test->entry())();
   EXPECT_FLOAT_EQ(0.0f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0x40800000\n"
       "movd xmm0,rax\n"
       "shufps xmm0,xmm0 [0]\n"
       "movaps xmm11,xmm0\n"
@@ -3856,10 +3856,10 @@
   uint32_t res = reinterpret_cast<PackedCompareEQCode>(test->entry())();
   EXPECT_EQ(static_cast<uword>(0x0), res);
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0x40000000\n"
       "movd xmm0,rax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "movl rax,0x........\n"
+      "movl rax,0x40800000\n"
       "movd xmm1,rax\n"
       "shufps xmm1,xmm1 [0]\n"
       "cmpps xmm0,xmm1 [eq]\n"
@@ -3915,10 +3915,10 @@
   uint32_t res = reinterpret_cast<PackedCompareNEQCode>(test->entry())();
   EXPECT_EQ(static_cast<uword>(0xFFFFFFFF), res);
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0x40000000\n"
       "movd xmm0,rax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "movl rax,0x........\n"
+      "movl rax,0x40800000\n"
       "movd xmm1,rax\n"
       "shufps xmm1,xmm1 [0]\n"
       "cmpps xmm0,xmm1 [neq]\n"
@@ -3943,10 +3943,10 @@
   uint32_t res = reinterpret_cast<PackedCompareLTCode>(test->entry())();
   EXPECT_EQ(static_cast<uword>(0xFFFFFFFF), res);
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0x40000000\n"
       "movd xmm0,rax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "movl rax,0x........\n"
+      "movl rax,0x40800000\n"
       "movd xmm1,rax\n"
       "shufps xmm1,xmm1 [0]\n"
       "cmpps xmm0,xmm1 [lt]\n"
@@ -3971,10 +3971,10 @@
   uint32_t res = reinterpret_cast<PackedCompareLECode>(test->entry())();
   EXPECT_EQ(static_cast<uword>(0xFFFFFFFF), res);
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0x40000000\n"
       "movd xmm0,rax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "movl rax,0x........\n"
+      "movl rax,0x40800000\n"
       "movd xmm1,rax\n"
       "shufps xmm1,xmm1 [0]\n"
       "cmpps xmm0,xmm1 [le]\n"
@@ -3999,10 +3999,10 @@
   uint32_t res = reinterpret_cast<PackedCompareNLTCode>(test->entry())();
   EXPECT_EQ(static_cast<uword>(0x0), res);
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0x40000000\n"
       "movd xmm0,rax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "movl rax,0x........\n"
+      "movl rax,0x40800000\n"
       "movd xmm1,rax\n"
       "shufps xmm1,xmm1 [0]\n"
       "cmpps xmm0,xmm1 [nlt]\n"
@@ -4027,10 +4027,10 @@
   uint32_t res = reinterpret_cast<PackedCompareNLECode>(test->entry())();
   EXPECT_EQ(static_cast<uword>(0x0), res);
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0x40000000\n"
       "movd xmm0,rax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "movl rax,0x........\n"
+      "movl rax,0x40800000\n"
       "movd xmm1,rax\n"
       "shufps xmm1,xmm1 [0]\n"
       "cmpps xmm0,xmm1 [nle]\n"
@@ -4063,10 +4063,10 @@
       "movq r12,[rdi+0x8]\n"
       "movq thr,rsi\n"
       "movq pp,[r12+0x27]\n"
-      "movl rax,0x........\n"
+      "movl rax,0x4144cccd\n"
       "movd xmm0,rax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "movq r11,[thr+0x...]\n"
+      "movq r11,[thr+0x2c8]\n"
       "xorps xmm0,[r11]\n"
       "shufps xmm0,xmm0 [aa]\n"
       "pop thr\n"
@@ -4100,10 +4100,10 @@
       "movq r12,[rdi+0x8]\n"
       "movq thr,rsi\n"
       "movq pp,[r12+0x27]\n"
-      "movl rax,-0x........\n"
+      "movl rax,-0x3e8b3333\n"
       "movd xmm0,rax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "movq r11,[thr+0x...]\n"
+      "movq r11,[thr+0x2d0]\n"
       "andps xmm0,[r11]\n"
       "shufps xmm0,xmm0 [aa]\n"
       "pop thr\n"
@@ -4135,10 +4135,10 @@
       "movq r12,[rdi+0x8]\n"
       "movq thr,rsi\n"
       "movq pp,[r12+0x27]\n"
-      "movl rax,0x........\n"
+      "movl rax,0x4144cccd\n"
       "movd xmm0,rax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "movq r11,[thr+0x...]\n"
+      "movq r11,[thr+0x2d8]\n"
       "andps xmm0,[r11]\n"
       "shufps xmm0,xmm0 [ff]\n"
       "pop thr\n"
@@ -4161,10 +4161,10 @@
   float res = reinterpret_cast<PackedMinCode>(test->entry())();
   EXPECT_FLOAT_EQ(2.0f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0x40000000\n"
       "movd xmm0,rax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "movl rax,0x........\n"
+      "movl rax,0x40800000\n"
       "movd xmm1,rax\n"
       "shufps xmm1,xmm1 [0]\n"
       "minps xmm0,xmm1\n"
@@ -4183,10 +4183,10 @@
   float res = reinterpret_cast<PackedMaxCode>(test->entry())();
   EXPECT_FLOAT_EQ(4.0f, res, 0.001f);
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0x40000000\n"
       "movd xmm0,rax\n"
       "shufps xmm0,xmm0 [0]\n"
-      "movl rax,0x........\n"
+      "movl rax,0x40800000\n"
       "movd xmm1,rax\n"
       "shufps xmm1,xmm1 [0]\n"
       "maxps xmm0,xmm1\n"
@@ -4288,7 +4288,7 @@
   EXPECT_EQ(static_cast<uword>(0x0), res);
   EXPECT_DISASSEMBLY_NOT_WINDOWS_ENDS_WITH(
       "movups xmm9,[rax]\n"
-      "movq r11,[thr+0x...]\n"
+      "movq r11,[thr+0x2c0]\n"
       "movups xmm0,[r11]\n"
       "xorps xmm0,xmm9\n"
       "push rax\n"
@@ -4635,7 +4635,7 @@
   EXPECT_FLOAT_EQ(1024.67, reinterpret_cast<DoubleFPMovesCode>(test->entry())(),
                   0.001);
   EXPECT_DISASSEMBLY(
-      "movq rax,0x................\n"
+      "movq rax,0x409002ae147ae148\n"
       "push pp\n"
       "push rax\n"
       "movsd xmm0,[rsp]\n"
@@ -4717,11 +4717,11 @@
   double res = reinterpret_cast<SingleFPOperationsCode>(test->entry())();
   EXPECT_FLOAT_EQ(7.668, res, 0.001);
   EXPECT_DISASSEMBLY(
-      "movq rax,0x................\n"
+      "movq rax,0x402899999999999a\n"
       "push rax\n"
       "movsd xmm0,[rsp]\n"
       "movsd xmm8,[rsp]\n"
-      "movq rax,0x................\n"
+      "movq rax,0x400b333333333333\n"
       "movq [rsp],rax\n"
       "movsd xmm12,[rsp]\n"
       "addsd xmm8,xmm12\n"
@@ -4756,9 +4756,9 @@
   double res = reinterpret_cast<Int32ToDoubleConversion>(test->entry())();
   EXPECT_FLOAT_EQ(-2.0, res, 0.001);
   EXPECT_DISASSEMBLY(
-      "movq r11,0x................\n"
+      "movq r11,0x1111111100000006\n"
       "cvtsi2sd xmm0,r11\n"
-      "movq r11,0x................\n"
+      "movq r11,0x2222222200000008\n"
       "cvtsi2sd xmm8,r11\n"
       "subsd xmm0,xmm8\n"
       "ret\n");
@@ -4778,7 +4778,7 @@
   double res = reinterpret_cast<Int64ToDoubleConversionCode>(test->entry())();
   EXPECT_FLOAT_EQ(static_cast<double>(12LL << 32), res, 0.001);
   EXPECT_DISASSEMBLY(
-      "movq rdx,0x................\n"
+      "movq rdx,0x0000000c00000000\n"
       "cvtsi2sd xmm0,rdx\n"
       "movsd xmm15,xmm0\n"
       "addsd xmm0,xmm0\n"
@@ -4818,16 +4818,16 @@
   int64_t res = reinterpret_cast<DoubleToInt64ConversionCode>(test->entry())();
   EXPECT_EQ(420000000000l, res);
   EXPECT_DISASSEMBLY(
-      "movq rax,0x................\n"
+      "movq rax,0x44a1c9a62d04ed0c\n"
       "push rax\n"
       "movsd xmm9,[rsp]\n"
       "pop rax\n"
       "cvttsd2siq rax,xmm9\n"
-      "movq r11,0x................\n"
+      "movq r11,0x8000000000000000\n"
       "cmpq rax,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
-      "movq rax,0x................\n"
+      "movq rax,0x4258727cda000000\n"
       "push rax\n"
       "movsd xmm9,[rsp]\n"
       "movsd xmm6,[rsp]\n"
@@ -4899,26 +4899,26 @@
   int64_t res = reinterpret_cast<DoubleToInt32ConversionCode>(test->entry())();
   EXPECT_EQ(42, res);
   EXPECT_DISASSEMBLY(
-      "movq rax,0x................\n"
+      "movq rax,0x4258727cda000000\n"
       "push rax\n"
       "movsd xmm9,[rsp]\n"
       "pop rax\n"
       "cvttsd2sil rax,xmm9\n"
-      "movl r11,0x........\n"
+      "movl r11,0x80000000\n"
       "cmpq rax,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
-      "movq rax,0x................\n"
+      "movq rax,0xc045000000000000\n"
       "push rax\n"
       "movsd xmm9,[rsp]\n"
       "pop rax\n"
       "movq r10,-1\n"
       "cvttsd2sil r10,xmm9\n"
-      "movl r11,0x........\n"
+      "movl r11,0xffffffd6\n"
       "cmpq r10,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
-      "movq rax,0x................\n"
+      "movq rax,0x4045000000000000\n"
       "push rax\n"
       "movsd xmm9,[rsp]\n"
       "movsd xmm6,[rsp]\n"
@@ -4983,24 +4983,24 @@
       "movq pp,[r12+0x27]\n"
       "movq rax,[pp+0xf]\n"
       "cmpq rax,[pp+0xf]\n"
-      "jnz 0x................\n"
+      "jnz +92\n"
       "movq rcx,[pp+0xf]\n"
       "cmpq rcx,[pp+0xf]\n"
-      "jnz 0x................\n"
+      "jnz +78\n"
       "movl rcx,0x1e\n"
       "cmpq rcx,0x1e\n"
-      "jnz 0x................\n"
+      "jnz +63\n"
       "push rax\n"
       "movq r11,[pp+0xf]\n"
       "movq [rsp],r11\n"
       "pop rcx\n"
       "cmpq rcx,[pp+0xf]\n"
-      "jnz 0x................\n"
+      "jnz +43\n"
       "push rax\n"
       "movq [rsp],0x1e\n"
       "pop rcx\n"
       "cmpq rcx,0x1e\n"
-      "jnz 0x................\n"
+      "jnz +23\n"
       "movl rax,1\n"
       "pop thr\n"
       "pop pp\n"
@@ -5027,24 +5027,24 @@
       "movq pp,[r12+0x27]\n"
       "movq rax,[pp+0xf]\n"
       "cmpl rax,[pp+0xf]\n"
-      "jnz 0x................\n"
+      "jnz +90\n"
       "movq rcx,[pp+0xf]\n"
       "cmpl rcx,[pp+0xf]\n"
-      "jnz 0x................\n"
+      "jnz +76\n"
       "movl rcx,0x1e\n"
       "cmpl rcx,0x1e\n"
-      "jnz 0x................\n"
+      "jnz +62\n"
       "push rax\n"
       "movq r11,[pp+0xf]\n"
       "movq [rsp],r11\n"
       "pop rcx\n"
       "cmpl rcx,[pp+0xf]\n"
-      "jnz 0x................\n"
+      "jnz +42\n"
       "push rax\n"
       "movq [rsp],0x1e\n"
       "pop rcx\n"
       "cmpl rcx,0x1e\n"
-      "jnz 0x................\n"
+      "jnz +23\n"
       "movl rax,1\n"
       "pop thr\n"
       "pop pp\n"
@@ -5207,7 +5207,7 @@
   unsigned int res = reinterpret_cast<TestNot>(test->entry())();
   EXPECT_EQ(0xFFFFFFFF, res);
   EXPECT_DISASSEMBLY(
-      "movq rax,0x................\n"
+      "movq rax,0xffffffff00000000\n"
       "notq rax\n"
       "ret\n");
 }
@@ -5269,7 +5269,7 @@
       "xorpd xmm0,xmm0\n"
       "xorpd xmm0,xmm15\n"
       "comisd xmm0,xmm15\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "ret\n");
 }
@@ -5334,7 +5334,7 @@
   int64_t res = reinterpret_cast<DoubleFPUStackMovesCode>(test->entry())();
   EXPECT_FLOAT_EQ(1024.67, (bit_cast<double, int64_t>(res)), 0.001);
   EXPECT_DISASSEMBLY(
-      "movq rax,0x................\n"
+      "movq rax,0x409002ae147ae148\n"
       "push rax\n"
       "fld_d [rsp]\n"
       "movq [rsp],0\n"
@@ -5464,7 +5464,7 @@
       "movq r12,[rdi+0x8]\n"
       "movq thr,rsi\n"
       "movq pp,[r12+0x27]\n"
-      "movq r11,[thr+0x...]\n"
+      "movq r11,[thr+0x2b8]\n"
       "andpd xmm0,[r11]\n"
       "pop thr\n"
       "pop pp\n"
@@ -5506,7 +5506,7 @@
   uword res = reinterpret_cast<TestSetCC>(test->entry())();
   EXPECT_EQ(0xFFFFFF00, res);
   EXPECT_DISASSEMBLY(
-      "movl rax,0x........\n"
+      "movl rax,0xffffffff\n"
       "cmpq rax,rax\n"
       "setnzl rax\n"
       "ret\n");
@@ -5528,7 +5528,7 @@
   EXPECT_EQ(0xFFFF01FF, res);
   EXPECT_DISASSEMBLY(
       "push rbx\n"
-      "movl rbx,0x........\n"
+      "movl rbx,0xffffffff\n"
       "cmpq rbx,rbx\n"
       "setzl rdi\n"
       "movq rax,rbx\n"
@@ -5552,7 +5552,7 @@
   EXPECT_EQ(0xFFFFFF00, res);
   EXPECT_DISASSEMBLY(
       "push r10\n"
-      "movl r10,0x........\n"
+      "movl r10,0xffffffff\n"
       "cmpq r10,r10\n"
       "setnzl r10\n"
       "movq rax,r10\n"
@@ -5576,7 +5576,7 @@
   EXPECT_EQ(0xFFFFFF01, res);
   EXPECT_DISASSEMBLY(
       "push rsi\n"
-      "movl rsi,0x........\n"
+      "movl rsi,0xffffffff\n"
       "cmpq rsi,rsi\n"
       "setzl rsi\n"
       "movq rax,rsi\n"
@@ -5834,7 +5834,7 @@
       "movl rax,4\n"
       "movl r11,2\n"
       "btq rax,r11\n"
-      "jc 0x................\n"
+      "jc +7\n"
       "int3\n"
       "movl rax,1\n"
       "ret\n");
@@ -5857,7 +5857,7 @@
   EXPECT_DISASSEMBLY(
       "movl r11,0x20\n"
       "bt r11,5\n"
-      "jc 0x................\n"
+      "jc +7\n"
       "int3\n"
       "movl rax,1\n"
       "ret\n");
@@ -5882,7 +5882,7 @@
   EXPECT_DISASSEMBLY_ENDS_WITH(
       "xorq rax,rax\n"
       "movl rcx,1\n"
-      "cmpq rdx,0x...\n"
+      "cmpq rdx,0x311\n"
       "cmovzq rax,rcx\n"
       "ret\n");
 }
@@ -6006,61 +6006,61 @@
   EXPECT_EQ(42, res);
   EXPECT_DISASSEMBLY(
       "movl rax,0x2a\n"
-      "imulq rax,rax,0x........\n"
-      "movq r11,0x................\n"
+      "imulq rax,rax,0x3b9aca00\n"
+      "movq r11,0x00000009c7652400\n"
       "cmpq rax,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "movl rax,0x2a\n"
-      "imull rax,rax,0x........\n"
-      "movl r11,0x........\n"
+      "imull rax,rax,0x3b9aca00\n"
+      "movl r11,0xc7652400\n"
       "cmpq rax,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
-      "movl rax,0x........\n"
-      "movq r11,0x................\n"
+      "movl rax,0x3b9aca00\n"
+      "movq r11,0x000000098bca5a00\n"
       "addq rax,r11\n"
-      "movq r11,0x................\n"
+      "movq r11,0x00000009c7652400\n"
       "cmpq rax,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
-      "movl rax,0x........\n"
-      "addl rax,0x........\n"
-      "addl rax,0x........\n"
-      "addl rax,0x........\n"
-      "movl r11,0x........\n"
+      "movl rax,0x3b9aca00\n"
+      "addl rax,0x3b9aca00\n"
+      "addl rax,0x3b9aca00\n"
+      "addl rax,0x3b9aca00\n"
+      "movl r11,0xee6b2800\n"
       "cmpq rax,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
-      "movl rax,0x........\n"
-      "subl rax,0x........\n"
-      "addl rax,0x........\n"
-      "subl rax,0x........\n"
-      "movl r11,0x........\n"
+      "movl rax,0x3b9aca00\n"
+      "subl rax,0x4d2fa200\n"
+      "addl rax,0x3b9aca00\n"
+      "subl rax,0x3b9aca00\n"
+      "movl r11,0xee6b2800\n"
       "cmpq rax,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
-      "movl rax,0x........\n"
-      "movq r11,0x................\n"
+      "movl rax,0x3b9aca00\n"
+      "movq r11,0x0000000a02ffee00\n"
       "subq rax,r11\n"
-      "movq r11,0x................\n"
+      "movq r11,0xfffffff6389adc00\n"
       "cmpq rax,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
-      "movq rax,-0x........\n"
-      "subl rax,0x........\n"
-      "subl rax,0x........\n"
-      "subl rax,0x........\n"
-      "cmpq rax,0x........\n"
-      "jz 0x................\n"
+      "movq rax,-0x3b9aca00\n"
+      "subl rax,0x3b9aca00\n"
+      "subl rax,0x3b9aca00\n"
+      "subl rax,0x3b9aca00\n"
+      "cmpq rax,0x1194d800\n"
+      "jz +7\n"
       "int3\n"
-      "movl rax,0x........\n"
-      "subl rax,0x........\n"
-      "subl rax,0x........\n"
-      "addl rax,0x........\n"
-      "movl r11,0x........\n"
+      "movl rax,0x3b9aca00\n"
+      "subl rax,0x4d2fa200\n"
+      "subl rax,0x3b9aca00\n"
+      "addl rax,0x3b9aca00\n"
+      "movl r11,0xee6b2800\n"
       "cmpq rax,r11\n"
-      "jz 0x................\n"
+      "jz +7\n"
       "int3\n"
       "movl rax,0x2a\n"
       "ret\n");
@@ -6261,10 +6261,10 @@
       "push rcx\n"
       "xorq rcx,rcx\n"
       "push rcx\n"
-      "subq rsp,0x...\n"
-      "movq [rsp+0x...],rdx\n"
-      "movq rax,[rsp+0x...]\n"
-      "addq rsp,0x...\n"
+      "subq rsp,0x400\n"
+      "movq [rsp+0x400],rdx\n"
+      "movq rax,[rsp+0x400]\n"
+      "addq rsp,0x400\n"
       "pop rcx\n"
       "pop rcx\n"
       "ret\n");
diff --git a/runtime/vm/compiler/assembler/disassembler.cc b/runtime/vm/compiler/assembler/disassembler.cc
index e9b082f..2777ccd 100644
--- a/runtime/vm/compiler/assembler/disassembler.cc
+++ b/runtime/vm/compiler/assembler/disassembler.cc
@@ -80,14 +80,16 @@
 }
 
 void DisassembleToJSONStream::Print(const char* format, ...) {
-  va_list args;
-  va_start(args, format);
-  intptr_t len = Utils::VSNPrint(NULL, 0, format, args);
-  va_end(args);
+  va_list measure_args;
+  va_start(measure_args, format);
+  intptr_t len = Utils::VSNPrint(NULL, 0, format, measure_args);
+  va_end(measure_args);
+
   char* p = reinterpret_cast<char*>(malloc(len + 1));
-  va_start(args, format);
-  intptr_t len2 = Utils::VSNPrint(p, len, format, args);
-  va_end(args);
+  va_list print_args;
+  va_start(print_args, format);
+  intptr_t len2 = Utils::VSNPrint(p, len, format, print_args);
+  va_end(print_args);
   ASSERT(len == len2);
   for (intptr_t i = 0; i < len; i++) {
     if (p[i] == '\n' || p[i] == '\r') {
@@ -134,10 +136,10 @@
   if (overflowed_) {
     return;
   }
-  va_list args;
-  va_start(args, format);
-  intptr_t len = Utils::VSNPrint(NULL, 0, format, args);
-  va_end(args);
+  va_list measure_args;
+  va_start(measure_args, format);
+  intptr_t len = Utils::VSNPrint(NULL, 0, format, measure_args);
+  va_end(measure_args);
   if (remaining_ < len + 100) {
     *buffer_++ = '.';
     *buffer_++ = '.';
@@ -147,9 +149,10 @@
     overflowed_ = true;
     return;
   }
-  va_start(args, format);
-  intptr_t len2 = Utils::VSNPrint(buffer_, len, format, args);
-  va_end(args);
+  va_list print_args;
+  va_start(print_args, format);
+  intptr_t len2 = Utils::VSNPrint(buffer_, len, format, print_args);
+  va_end(print_args);
   ASSERT(len == len2);
   buffer_ += len;
   remaining_ -= len;
@@ -293,10 +296,9 @@
   {
     const auto& stackmaps =
         CompressedStackMaps::Handle(zone, code.compressed_stackmaps());
-    CompressedStackMaps::Iterator it(thread, stackmaps);
     TextBuffer buffer(100);
     buffer.Printf("StackMaps for function '%s' {\n", function_fullname);
-    it.WriteToBuffer(&buffer, "\n");
+    stackmaps.WriteToBuffer(&buffer, "\n");
     buffer.AddString("}\n");
     THR_Print("%s", buffer.buffer());
   }
diff --git a/runtime/vm/compiler/assembler/disassembler_arm64.cc b/runtime/vm/compiler/assembler/disassembler_arm64.cc
index 8f441ef..490569d 100644
--- a/runtime/vm/compiler/assembler/disassembler_arm64.cc
+++ b/runtime/vm/compiler/assembler/disassembler_arm64.cc
@@ -244,7 +244,7 @@
         buffer_pos_ +=
             Utils::SNPrint(current_position_in_buffer(),
                            remaining_size_in_buffer(), ", #%d", imm9);
-        Print("] !");
+        Print("]!");
         break;
       }
       default: { Print("???"); }
@@ -269,13 +269,13 @@
       // rn + (imm7 << (2 + B31)), pre-index, no writeback.
       buffer_pos_ +=
           Utils::SNPrint(current_position_in_buffer(),
-                         remaining_size_in_buffer(), ", #%d ]", offset);
+                         remaining_size_in_buffer(), ", #%d]", offset);
       break;
     case 3:
       // rn + (imm7 << (2 + B31)), pre-index, writeback.
       buffer_pos_ +=
           Utils::SNPrint(current_position_in_buffer(),
-                         remaining_size_in_buffer(), ", #%d ]!", offset);
+                         remaining_size_in_buffer(), ", #%d]!", offset);
       break;
     default:
       Print(", ???]");
@@ -453,7 +453,7 @@
       if (shift != 0) {
         buffer_pos_ +=
             Utils::SNPrint(current_position_in_buffer(),
-                           remaining_size_in_buffer(), "lsl %d", shift);
+                           remaining_size_in_buffer(), " lsl %d", shift);
       }
       return 2;
     }
@@ -505,7 +505,7 @@
         }
         buffer_pos_ +=
             Utils::SNPrint(current_position_in_buffer(),
-                           remaining_size_in_buffer(), "0x%" Px64, imm);
+                           remaining_size_in_buffer(), "#0x%" Px64, imm);
         return ret;
       } else {
         ASSERT(STRING_STARTS_WITH(format, "imm"));
@@ -631,7 +631,8 @@
             sz_str = "w";
             break;
           case 3:
-            sz_str = "x";
+            // 64-bit width is most commonly used, no need to print "x".
+            sz_str = "";
             break;
           default:
             sz_str = "?";
@@ -683,13 +684,13 @@
 void ARM64Decoder::DecodeMoveWide(Instr* instr) {
   switch (instr->Bits(29, 2)) {
     case 0:
-      Format(instr, "movn'sf 'rd, 'imm16 'hw");
+      Format(instr, "movn'sf 'rd, 'imm16'hw");
       break;
     case 2:
-      Format(instr, "movz'sf 'rd, 'imm16 'hw");
+      Format(instr, "movz'sf 'rd, 'imm16'hw");
       break;
     case 3:
-      Format(instr, "movk'sf 'rd, 'imm16 'hw");
+      Format(instr, "movk'sf 'rd, 'imm16'hw");
       break;
     default:
       Unknown(instr);
@@ -740,11 +741,8 @@
 }
 
 void ARM64Decoder::DecodeLoadStoreExclusive(Instr* instr) {
-  if (instr->Bit(21) != 0 || instr->Bit(23) != instr->Bit(15)) {
-    Unknown(instr);
-  }
-  const int32_t size = instr->Bits(30, 2);
-  if (size != 3) {
+  if (instr->Bit(32) != 1 || instr->Bit(21) != 0 ||
+      instr->Bit(23) != instr->Bit(15)) {
     Unknown(instr);
   }
 
@@ -754,16 +752,16 @@
   if (is_load) {
     const bool is_load_acquire = !is_exclusive && is_ordered;
     if (is_load_acquire) {
-      Format(instr, "ldar 'rt, 'rn");
+      Format(instr, "ldar'sz 'rt, 'rn");
     } else {
-      Format(instr, "ldxr 'rt, 'rn");
+      Format(instr, "ldxr'sz 'rt, 'rn");
     }
   } else {
     const bool is_store_release = !is_exclusive && is_ordered;
     if (is_store_release) {
-      Format(instr, "stlr 'rt, 'rn");
+      Format(instr, "stlr'sz 'rt, 'rn");
     } else {
-      Format(instr, "stxr 'rs, 'rt, 'rn");
+      Format(instr, "stxr'sz 'rs, 'rt, 'rn");
     }
   }
 }
@@ -772,22 +770,22 @@
   switch (instr->Bit(30)) {
     case 0: {
       if ((instr->RdField() == R31) && (instr->SField() == 1)) {
-        Format(instr, "cmni'sf 'rn, 'imm12s");
+        Format(instr, "cmn'sf 'rn, 'imm12s");
       } else {
         if (((instr->RdField() == R31) || (instr->RnField() == R31)) &&
             (instr->Imm12Field() == 0) && (instr->Bit(29) == 0)) {
           Format(instr, "mov'sf 'rd, 'rn");
         } else {
-          Format(instr, "addi'sf's 'rd, 'rn, 'imm12s");
+          Format(instr, "add'sf's 'rd, 'rn, 'imm12s");
         }
       }
       break;
     }
     case 1: {
       if ((instr->RdField() == R31) && (instr->SField() == 1)) {
-        Format(instr, "cmpi'sf 'rn, 'imm12s");
+        Format(instr, "cmp'sf 'rn, 'imm12s");
       } else {
-        Format(instr, "subi'sf's 'rd, 'rn, 'imm12s");
+        Format(instr, "sub'sf's 'rd, 'rn, 'imm12s");
       }
       break;
     }
@@ -836,8 +834,8 @@
         }
       }
       if ((s_imm != (reg_size - 1)) && ((s_imm + 1) == r_imm)) {
-        int shift = reg_size - s_imm;
-        Format(instr, "lsl'sf 'rd, 'rn, ");
+        int shift = reg_size - s_imm - 1;
+        Format(instr, "lsl'sf 'rd, 'rn, #");
         PrintInt(shift);
         break;
       } else if (s_imm == (reg_size - 1)) {
@@ -856,21 +854,25 @@
   int op = instr->Bits(29, 2);
   switch (op) {
     case 0:
-      Format(instr, "andi'sf 'rd, 'rn, 'bitimm");
+      Format(instr, "and'sf 'rd, 'rn, 'bitimm");
       break;
     case 1: {
       if (instr->RnField() == R31) {
         Format(instr, "mov'sf 'rd, 'bitimm");
       } else {
-        Format(instr, "orri'sf 'rd, 'rn, 'bitimm");
+        Format(instr, "orr'sf 'rd, 'rn, 'bitimm");
       }
       break;
     }
     case 2:
-      Format(instr, "eori'sf 'rd, 'rn, 'bitimm");
+      Format(instr, "eor'sf 'rd, 'rn, 'bitimm");
       break;
     case 3:
-      Format(instr, "andi'sfs 'rd, 'rn, 'bitimm");
+      if (instr->RdField() == R31) {
+        Format(instr, "tst'sf 'rn, 'bitimm");
+      } else {
+        Format(instr, "and'sfs 'rd, 'rn, 'bitimm");
+      }
       break;
     default:
       Unknown(instr);
@@ -948,7 +950,11 @@
         Format(instr, "blr 'rn");
         break;
       case 2:
-        Format(instr, "ret 'rn");
+        if (instr->RnField() == LINK_REGISTER) {
+          Format(instr, "ret");
+        } else {
+          Format(instr, "ret 'rn");
+        }
         break;
       default:
         Unknown(instr);
@@ -1040,7 +1046,11 @@
       if ((instr->RdField() == R31) && (instr->SFField())) {
         Format(instr, "cmp'sf 'rn, 'shift_op");
       } else {
-        Format(instr, "sub'sf's 'rd, 'rn, 'shift_op");
+        if (instr->RnField() == R31) {
+          Format(instr, "neg'sf's 'rd, 'shift_op");
+        } else {
+          Format(instr, "sub'sf's 'rd, 'rn, 'shift_op");
+        }
       }
       break;
     }
@@ -1116,6 +1126,9 @@
 
   const int op = instr->Bits(10, 10);
   switch (op) {
+    case 0:
+      Format(instr, "rbit'sf 'rd, 'rn");
+      break;
     case 4:
       Format(instr, "clz'sf 'rd, 'rn");
       break;
@@ -1208,24 +1221,24 @@
   bool non_select =
       (instr->RnField() == instr->RmField()) && ((cond & 0xe) != 0xe);
   if ((instr->Bits(29, 2) == 0) && (instr->Bits(10, 2) == 0)) {
-    Format(instr, "mov'sf'cond 'rd, 'rn, 'rm");
+    Format(instr, "csel'sf 'rd, 'rn, 'rm, 'cond");
   } else if ((instr->Bits(29, 2) == 0) && (instr->Bits(10, 2) == 1)) {
     if (non_select) {
-      Format(instr, "csinc'sf'cond 'rd, 'rn, 'rm");
+      Format(instr, "csinc'sf 'rd, 'rn, 'rm, 'cond");
     } else {
-      Format(instr, "cinc'sf'condinverted 'rd, 'rn");
+      Format(instr, "cinc'sf 'rd, 'rn, 'condinverted");
     }
   } else if ((instr->Bits(29, 2) == 2) && (instr->Bits(10, 2) == 0)) {
     if (non_select) {
-      Format(instr, "cinv'sf'condinverted 'rd, 'rn");
+      Format(instr, "cinv'sf 'rd, 'rn, 'condinverted");
     } else {
-      Format(instr, "csinv'sf'cond 'rd, 'rn, 'rm");
+      Format(instr, "csinv'sf 'rd, 'rn, 'rm, 'cond");
     }
   } else if ((instr->Bits(29, 2) == 2) && (instr->Bits(10, 2) == 1)) {
     if (non_select) {
-      Format(instr, "cneg'sf'condinverted 'rd, 'rn");
+      Format(instr, "cneg'sf 'rd, 'rn, 'condinverted");
     } else {
-      Format(instr, "csneg'sf'cond 'rd, 'rn, 'rm");
+      Format(instr, "csneg'sf 'rd, 'rn, 'rm, 'cond");
     }
   } else {
     Unknown(instr);
diff --git a/runtime/vm/compiler/assembler/disassembler_x86.cc b/runtime/vm/compiler/assembler/disassembler_x86.cc
index 77021e4..fb4c917 100644
--- a/runtime/vm/compiler/assembler/disassembler_x86.cc
+++ b/runtime/vm/compiler/assembler/disassembler_x86.cc
@@ -404,9 +404,14 @@
   switch (mod) {
     case 0:
       if ((rm & 7) == 5) {
+#if defined(TARGET_ARCH_IA32)
+        int32_t abs = LoadUnaligned(reinterpret_cast<int32_t*>(modrmp + 1));
+        Print("[%#x]", abs);
+#else
         int32_t disp = LoadUnaligned(reinterpret_cast<int32_t*>(modrmp + 1));
         Print("[rip");
         PrintDisp(disp, "]");
+#endif
         return 5;
       } else if ((rm & 7) == 4) {
         // Codes for SIB byte.
diff --git a/runtime/vm/compiler/backend/flow_graph_compiler.cc b/runtime/vm/compiler/backend/flow_graph_compiler.cc
index 9e56049..a6d5418 100644
--- a/runtime/vm/compiler/backend/flow_graph_compiler.cc
+++ b/runtime/vm/compiler/backend/flow_graph_compiler.cc
@@ -223,16 +223,14 @@
       BlockEntryInstr* entry = block_order_[i];
       for (ForwardInstructionIterator it(entry); !it.Done(); it.Advance()) {
         Instruction* current = it.Current();
-        if (current->IsBranch()) {
-          current = current->AsBranch()->comparison();
+        if (auto* branch = current->AsBranch()) {
+          current = branch->comparison();
         }
-        // In optimized code, ICData is always set in the instructions.
-        const ICData* ic_data = NULL;
-        if (current->IsInstanceCall()) {
-          ic_data = current->AsInstanceCall()->ic_data();
-        }
-        if ((ic_data != NULL) && (ic_data->NumberOfUsedChecks() == 0)) {
-          may_reoptimize_ = true;
+        if (auto* instance_call = current->AsInstanceCall()) {
+          const ICData* ic_data = instance_call->ic_data();
+          if ((ic_data == nullptr) || (ic_data->NumberOfUsedChecks() == 0)) {
+            may_reoptimize_ = true;
+          }
         }
       }
     }
diff --git a/runtime/vm/compiler/backend/flow_graph_compiler.h b/runtime/vm/compiler/backend/flow_graph_compiler.h
index 7bf8100..975e431 100644
--- a/runtime/vm/compiler/backend/flow_graph_compiler.h
+++ b/runtime/vm/compiler/backend/flow_graph_compiler.h
@@ -471,7 +471,6 @@
 
   static bool SupportsUnboxedDoubles();
   static bool SupportsUnboxedSimd128();
-  static bool SupportsHardwareDivision();
   static bool CanConvertInt64ToDouble();
 
   // Accessors.
diff --git a/runtime/vm/compiler/backend/flow_graph_compiler_arm.cc b/runtime/vm/compiler/backend/flow_graph_compiler_arm.cc
index 3402cb2..d95dd98 100644
--- a/runtime/vm/compiler/backend/flow_graph_compiler_arm.cc
+++ b/runtime/vm/compiler/backend/flow_graph_compiler_arm.cc
@@ -66,17 +66,13 @@
 }
 
 bool FlowGraphCompiler::SupportsUnboxedDoubles() {
-  return TargetCPUFeatures::vfp_supported() && FLAG_unbox_doubles;
+  return FLAG_unbox_doubles;
 }
 
 bool FlowGraphCompiler::SupportsUnboxedSimd128() {
   return TargetCPUFeatures::neon_supported() && FLAG_enable_simd_inline;
 }
 
-bool FlowGraphCompiler::SupportsHardwareDivision() {
-  return TargetCPUFeatures::can_divide();
-}
-
 bool FlowGraphCompiler::CanConvertInt64ToDouble() {
   // ARM does not have a short instruction sequence for converting int64 to
   // double.
diff --git a/runtime/vm/compiler/backend/flow_graph_compiler_arm64.cc b/runtime/vm/compiler/backend/flow_graph_compiler_arm64.cc
index d7e4d14..abad72a 100644
--- a/runtime/vm/compiler/backend/flow_graph_compiler_arm64.cc
+++ b/runtime/vm/compiler/backend/flow_graph_compiler_arm64.cc
@@ -73,10 +73,6 @@
   return true;
 }
 
-bool FlowGraphCompiler::SupportsHardwareDivision() {
-  return true;
-}
-
 void FlowGraphCompiler::EnterIntrinsicMode() {
   ASSERT(!intrinsic_mode());
   intrinsic_mode_ = true;
diff --git a/runtime/vm/compiler/backend/flow_graph_compiler_ia32.cc b/runtime/vm/compiler/backend/flow_graph_compiler_ia32.cc
index d613572..1daf4c0 100644
--- a/runtime/vm/compiler/backend/flow_graph_compiler_ia32.cc
+++ b/runtime/vm/compiler/backend/flow_graph_compiler_ia32.cc
@@ -48,10 +48,6 @@
   return FLAG_enable_simd_inline;
 }
 
-bool FlowGraphCompiler::SupportsHardwareDivision() {
-  return true;
-}
-
 bool FlowGraphCompiler::CanConvertInt64ToDouble() {
   return true;
 }
diff --git a/runtime/vm/compiler/backend/flow_graph_compiler_x64.cc b/runtime/vm/compiler/backend/flow_graph_compiler_x64.cc
index 03922aa..91cc786 100644
--- a/runtime/vm/compiler/backend/flow_graph_compiler_x64.cc
+++ b/runtime/vm/compiler/backend/flow_graph_compiler_x64.cc
@@ -70,10 +70,6 @@
   return FLAG_enable_simd_inline;
 }
 
-bool FlowGraphCompiler::SupportsHardwareDivision() {
-  return true;
-}
-
 bool FlowGraphCompiler::CanConvertInt64ToDouble() {
   return true;
 }
diff --git a/runtime/vm/compiler/backend/il.cc b/runtime/vm/compiler/backend/il.cc
index c3683d0..878bcec 100644
--- a/runtime/vm/compiler/backend/il.cc
+++ b/runtime/vm/compiler/backend/il.cc
@@ -1299,12 +1299,15 @@
   // TODO(fschneider): Implement a faster way to get the block of an
   // instruction.
   Instruction* result = previous();
-  ASSERT(result != nullptr);
-  while (!result->IsBlockEntry()) {
+  while ((result != nullptr) && !result->IsBlockEntry()) {
     result = result->previous();
-    ASSERT(result != nullptr);
   }
-  return result->AsBlockEntry();
+  // InlineExitCollector::RemoveUnreachableExits may call
+  // Instruction::GetBlock on instructions which are not properly linked
+  // to the flow graph (as collected exits may belong to unreachable
+  // fragments), so this code should gracefully handle the absence of
+  // BlockEntry.
+  return (result != nullptr) ? result->AsBlockEntry() : nullptr;
 }
 
 void ForwardInstructionIterator::RemoveCurrentFromGraph() {
@@ -4260,7 +4263,6 @@
     stub = object_store->init_instance_field_stub();
   } else if (field.is_late()) {
     if (!field.has_nontrivial_initializer()) {
-      // Common stub calls runtime which will throw an exception.
       stub = object_store->init_instance_field_stub();
     } else {
       // Stubs for late field initialization call initializer
diff --git a/runtime/vm/compiler/backend/il.h b/runtime/vm/compiler/backend/il.h
index 3ef43cc..c261131 100644
--- a/runtime/vm/compiler/backend/il.h
+++ b/runtime/vm/compiler/backend/il.h
@@ -5596,15 +5596,11 @@
                     const Field* field = nullptr)
       : Base(source, deopt_id),
         token_pos_(source.token_pos),
-        calls_initializer_(calls_initializer),
-        throw_exception_on_initialization_(false) {
+        throw_exception_on_initialization_(
+            field != nullptr && !field->has_initializer() && field->is_late()),
+        calls_initializer_(calls_initializer) {
+    ASSERT(!calls_initializer || field != nullptr);
     ASSERT(!calls_initializer || (deopt_id != DeoptId::kNone));
-    if (calls_initializer_) {
-      ASSERT(field != nullptr);
-      throw_exception_on_initialization_ = !field->needs_load_guard() &&
-                                           field->is_late() &&
-                                           !field->has_initializer();
-    }
   }
 
   virtual TokenPosition token_pos() const { return token_pos_; }
@@ -5634,15 +5630,19 @@
   }
 
   virtual bool CanCallDart() const {
-    return calls_initializer() && !throw_exception_on_initialization();
+    // The slow path (running the field initializer) always calls one of a
+    // specific set of stubs. For those stubs that do not simply call the
+    // runtime, the GC recognizes their frames and restores write barriers
+    // automatically (see Thread::RestoreWriteBarrierInvariant).
+    return false;
   }
   virtual bool CanTriggerGC() const { return calls_initializer(); }
   virtual bool MayThrow() const { return calls_initializer(); }
 
  private:
   const TokenPosition token_pos_;
+  const bool throw_exception_on_initialization_;
   bool calls_initializer_;
-  bool throw_exception_on_initialization_;
 
   DISALLOW_COPY_AND_ASSIGN(TemplateLoadField);
 };
diff --git a/runtime/vm/compiler/backend/il_arm.cc b/runtime/vm/compiler/backend/il_arm.cc
index 3e956fe..d15b079 100644
--- a/runtime/vm/compiler/backend/il_arm.cc
+++ b/runtime/vm/compiler/backend/il_arm.cc
@@ -4139,7 +4139,6 @@
       break;
     }
     case Token::kTRUNCDIV: {
-      ASSERT(TargetCPUFeatures::can_divide());
       if (RangeUtils::CanBeZero(right_range())) {
         // Handle divide by zero in runtime.
         __ cmp(right, compiler::Operand(0));
@@ -4161,7 +4160,6 @@
       break;
     }
     case Token::kMOD: {
-      ASSERT(TargetCPUFeatures::can_divide());
       if (RangeUtils::CanBeZero(right_range())) {
         // Handle divide by zero in runtime.
         __ cmp(right, compiler::Operand(0));
@@ -6229,7 +6227,6 @@
   compiler::Label* deopt =
       compiler->AddDeoptStub(deopt_id(), ICData::kDeoptBinarySmiOp);
 
-  ASSERT(TargetCPUFeatures::can_divide());
   const Register left = locs()->in(0).reg();
   const Register right = locs()->in(1).reg();
   ASSERT(locs()->out(0).IsPairLocation());
diff --git a/runtime/vm/compiler/backend/il_x64.cc b/runtime/vm/compiler/backend/il_x64.cc
index c770204..378537a 100644
--- a/runtime/vm/compiler/backend/il_x64.cc
+++ b/runtime/vm/compiler/backend/il_x64.cc
@@ -1154,8 +1154,9 @@
   // Push the result place holder initialized to NULL.
   __ PushObject(Object::null_object());
 
-  // Pass a pointer to the first argument in RAX.
-  __ leaq(RAX, compiler::Address(RSP, ArgumentCount() * kWordSize));
+  // Pass a pointer to the first argument in R13 (we avoid using RAX here to
+  // simplify the stub code that will call native code).
+  __ leaq(R13, compiler::Address(RSP, ArgumentCount() * kWordSize));
 
   __ LoadImmediate(R10, compiler::Immediate(argc_tag));
   const Code* stub;
@@ -5240,11 +5241,12 @@
   compiler->AddSlowPathCode(slow_path);
 
   if (recognized_kind() != MethodRecognizer::kDoubleToInteger) {
-    // In JIT mode VM knows target CPU features at compile time
-    // and can pick more optimal representation for DoubleToDouble
-    // conversion. In AOT mode we test if roundsd instruction is
-    // available at run time and fall back to stub if it isn't.
-    ASSERT(CompilerState::Current().is_aot());
+    // In JIT mode without --target-unknown-cpu VM knows target CPU features
+    // at compile time and can pick more optimal representation
+    // for DoubleToDouble conversion. In AOT mode and with
+    // --target-unknown-cpu we test if roundsd instruction is available
+    // at run time and fall back to stub if it isn't.
+    ASSERT(CompilerState::Current().is_aot() || FLAG_target_unknown_cpu);
     if (FLAG_use_slow_path) {
       __ jmp(slow_path->entry_label());
       __ Bind(slow_path->exit_label());
diff --git a/runtime/vm/compiler/backend/locations.h b/runtime/vm/compiler/backend/locations.h
index dd01b09..56c5604 100644
--- a/runtime/vm/compiler/backend/locations.h
+++ b/runtime/vm/compiler/backend/locations.h
@@ -597,15 +597,9 @@
       Add(Location::RegisterLocation(reg));
     }
 
-#if defined(TARGET_ARCH_ARM)
-    if (TargetCPUFeatures::vfp_supported()) {
-#endif
       for (intptr_t i = kNumberOfFpuRegisters - 1; i >= 0; --i) {
         Add(Location::FpuRegisterLocation(static_cast<FpuRegister>(i)));
       }
-#if defined(TARGET_ARCH_ARM)
-    }
-#endif
   }
 
   void AddAllArgumentRegisters() {
diff --git a/runtime/vm/compiler/call_specializer.cc b/runtime/vm/compiler/call_specializer.cc
index 90d1657..c6325a5 100644
--- a/runtime/vm/compiler/call_specializer.cc
+++ b/runtime/vm/compiler/call_specializer.cc
@@ -539,7 +539,6 @@
       }
       break;
     case Token::kDIV:
-      if (!FlowGraphCompiler::SupportsHardwareDivision()) return false;
       if (ShouldSpecializeForDouble(binary_feedback) ||
           binary_feedback.OperandsAre(kSmiCid)) {
         operands_type = kDoubleCid;
@@ -593,7 +592,6 @@
       break;
     case Token::kMOD:
     case Token::kTRUNCDIV:
-      if (!FlowGraphCompiler::SupportsHardwareDivision()) return false;
       if (binary_feedback.OperandsAre(kSmiCid)) {
         if (call->ic_data()->HasDeoptReason(ICData::kDeoptBinarySmiOp)) {
           return false;
diff --git a/runtime/vm/compiler/ffi/abi.cc b/runtime/vm/compiler/ffi/abi.cc
index 25900e4..c902a89 100644
--- a/runtime/vm/compiler/ffi/abi.cc
+++ b/runtime/vm/compiler/ffi/abi.cc
@@ -47,42 +47,58 @@
 
 #if defined(DART_TARGET_OS_ANDROID)
 #define DART_TARGET_OS_NAME Android
+#define DART_TARGET_OS_NAME_LC android
 #elif defined(DART_TARGET_OS_FUCHSIA)
 #define DART_TARGET_OS_NAME Fuchsia
+#define DART_TARGET_OS_NAME_LC fuchsia
 #elif defined(DART_TARGET_OS_LINUX)
 #define DART_TARGET_OS_NAME Linux
+#define DART_TARGET_OS_NAME_LC linux
 #elif defined(DART_TARGET_OS_MACOS)
 #if DART_TARGET_OS_MACOS_IOS
 #define DART_TARGET_OS_NAME IOS
+#define DART_TARGET_OS_NAME_LC ios
 #else
 #define DART_TARGET_OS_NAME MacOS
+#define DART_TARGET_OS_NAME_LC macos
 #endif
 #elif defined(DART_TARGET_OS_WINDOWS)
 #define DART_TARGET_OS_NAME Windows
+#define DART_TARGET_OS_NAME_LC windows
 #else
 #error Unknown OS
 #endif
 
 #if defined(TARGET_ARCH_IA32)
 #define TARGET_ARCH_NAME IA32
+#define TARGET_ARCH_NAME_LC ia32
 #elif defined(TARGET_ARCH_X64)
 #define TARGET_ARCH_NAME X64
+#define TARGET_ARCH_NAME_LC x64
 #elif defined(TARGET_ARCH_ARM)
 #define TARGET_ARCH_NAME Arm
+#define TARGET_ARCH_NAME_LC arm
 #elif defined(TARGET_ARCH_ARM64)
 #define TARGET_ARCH_NAME Arm64
+#define TARGET_ARCH_NAME_LC arm64
 #else
 #error Unknown arch
 #endif
 
-#define ABI_NAME1(os, arch) k##os##arch
-#define ABI_NAME2(os, arch) ABI_NAME1(os, arch)
-#define ABI_NAME3 ABI_NAME2(DART_TARGET_OS_NAME, TARGET_ARCH_NAME)
+#define ABI_ENUM_VALUE1(os, arch) k##os##arch
+#define ABI_ENUM_VALUE2(os, arch) ABI_ENUM_VALUE1(os, arch)
+#define ABI_ENUM_VALUE3 ABI_ENUM_VALUE2(DART_TARGET_OS_NAME, TARGET_ARCH_NAME)
 
 Abi TargetAbi() {
-  return Abi::ABI_NAME3;
+  return Abi::ABI_ENUM_VALUE3;
 }
 
+#define STRINGIFY2(s) STRINGIFY(s)
+#define STRINGIFY(s) #s
+
+const char* target_abi_name =
+    STRINGIFY2(DART_TARGET_OS_NAME_LC) "_" STRINGIFY2(TARGET_ARCH_NAME_LC);
+
 }  // namespace ffi
 
 }  // namespace compiler
diff --git a/runtime/vm/compiler/ffi/abi.h b/runtime/vm/compiler/ffi/abi.h
index 118054f..81b76d9 100644
--- a/runtime/vm/compiler/ffi/abi.h
+++ b/runtime/vm/compiler/ffi/abi.h
@@ -39,16 +39,23 @@
   kWindowsIA32,
   kWindowsX64,
 };
+
+const int64_t num_abis = static_cast<int64_t>(Abi::kWindowsX64) + 1;
+
 // We use the integer values of this enum in
-// runtime/vm/compiler/frontend/kernel_to_il.cc
+// - runtime/vm/compiler/ffi/native_type.cc
+// - runtime/vm/compiler/frontend/kernel_to_il.cc
 static_assert(static_cast<int64_t>(Abi::kAndroidArm) == 0,
               "Enum value unexpected.");
 static_assert(static_cast<int64_t>(Abi::kWindowsX64) == 17,
               "Enum value unexpected.");
+static_assert(num_abis == 18, "Enum value unexpected.");
 
 // The target ABI. Defines sizes and alignment of native types.
 Abi TargetAbi();
 
+extern const char* target_abi_name;
+
 }  // namespace ffi
 
 }  // namespace compiler
diff --git a/runtime/vm/compiler/ffi/marshaller.cc b/runtime/vm/compiler/ffi/marshaller.cc
index 6cf5ece..ca4f6d6 100644
--- a/runtime/vm/compiler/ffi/marshaller.cc
+++ b/runtime/vm/compiler/ffi/marshaller.cc
@@ -91,17 +91,22 @@
   if (IsFfiTypeClassId(type.type_class_id())) {
     return false;
   }
-#ifdef DEBUG
   const auto& cls = Class::Handle(this->zone_, type.type_class());
   const auto& superClass = Class::Handle(this->zone_, cls.SuperClass());
-  // TODO(http://dartbug.com/42563): Implement AbiSpecificInt.
+  const bool is_abi_specific_int =
+      String::Handle(this->zone_, superClass.UserVisibleName())
+          .Equals(Symbols::AbiSpecificInteger());
+  if (is_abi_specific_int) {
+    return false;
+  }
+#ifdef DEBUG
   const bool is_struct =
       String::Handle(this->zone_, superClass.UserVisibleName())
           .Equals(Symbols::Struct());
   const bool is_union =
       String::Handle(this->zone_, superClass.UserVisibleName())
           .Equals(Symbols::Union());
-  RELEASE_ASSERT(is_struct || is_union);
+  ASSERT(is_struct || is_union);
 #endif
   return true;
 }
diff --git a/runtime/vm/compiler/ffi/native_type.cc b/runtime/vm/compiler/ffi/native_type.cc
index bf4d452a..ac49f39 100644
--- a/runtime/vm/compiler/ffi/native_type.cc
+++ b/runtime/vm/compiler/ffi/native_type.cc
@@ -474,7 +474,33 @@
   }
 }
 
-// TODO(http://dartbug.com/42563): Implement AbiSpecificInt.
+static const NativeType* AbiSpecificFromPragma(Zone* zone,
+                                               const Instance& pragma,
+                                               const Class& abi_specific_int,
+                                               const char** error) {
+  const auto& clazz = Class::Handle(zone, pragma.clazz());
+  const auto& fields = Array::Handle(zone, clazz.fields());
+  ASSERT(fields.Length() == 1);
+  const auto& native_types_field =
+      Field::Handle(zone, Field::RawCast(fields.At(0)));
+  ASSERT(String::Handle(zone, native_types_field.name())
+             .Equals(Symbols::FfiNativeTypes()));
+  const auto& native_types =
+      Array::Handle(zone, Array::RawCast(pragma.GetField(native_types_field)));
+
+  ASSERT(native_types.Length() == num_abis);
+  const int64_t abi_index = static_cast<int64_t>(TargetAbi());
+  const auto& abi_abstract_type = AbstractType::Handle(
+      zone, AbstractType::RawCast(native_types.At(abi_index)));
+  if (abi_abstract_type.IsNull()) {
+    *error = zone->PrintToString(
+        "AbiSpecificInteger '%s' is missing mapping for '%s'.",
+        abi_specific_int.UserVisibleNameCString(), target_abi_name);
+    return nullptr;
+  }
+  return NativeType::FromAbstractType(zone, abi_abstract_type, error);
+}
+
 const NativeType* NativeType::FromAbstractType(Zone* zone,
                                                const AbstractType& type,
                                                const char** error) {
@@ -483,18 +509,26 @@
     return &NativeType::FromTypedDataClassId(zone, class_id);
   }
 
-  // User-defined structs or unions.
+  // User-defined structs, unions, or Abi-specific integers.
   const auto& cls = Class::Handle(zone, type.type_class());
   const auto& superClass = Class::Handle(zone, cls.SuperClass());
   const bool is_struct = String::Handle(zone, superClass.UserVisibleName())
                              .Equals(Symbols::Struct());
   const bool is_union = String::Handle(zone, superClass.UserVisibleName())
                             .Equals(Symbols::Union());
-  RELEASE_ASSERT(is_struct || is_union);
+  const bool is_abi_specific_int =
+      String::Handle(zone, superClass.UserVisibleName())
+          .Equals(Symbols::AbiSpecificInteger());
+  RELEASE_ASSERT(is_struct || is_union || is_abi_specific_int);
 
   auto& pragmas = Object::Handle(zone);
   String& pragma_name = String::Handle(zone);
-  pragma_name = Symbols::vm_ffi_struct_fields().ptr();
+  if (is_struct || is_union) {
+    pragma_name = Symbols::vm_ffi_struct_fields().ptr();
+  } else {
+    ASSERT(is_abi_specific_int);
+    pragma_name = Symbols::vm_ffi_abi_specific_mapping().ptr();
+  }
   Library::FindPragma(dart::Thread::Current(), /*only_core=*/false, cls,
                       pragma_name, /*multiple=*/true, &pragmas);
   ASSERT(!pragmas.IsNull());
@@ -503,7 +537,13 @@
   auto& pragma = Instance::Handle(zone);
   auto& clazz = Class::Handle(zone);
   auto& library = Library::Handle(zone);
-  const String& class_symbol = Symbols::FfiStructLayout();
+  String& class_symbol = String::Handle(zone);
+  if (is_struct || is_union) {
+    class_symbol = Symbols::FfiStructLayout().ptr();
+  } else {
+    ASSERT(is_abi_specific_int);
+    class_symbol = Symbols::FfiAbiSpecificMapping().ptr();
+  }
   for (intptr_t i = 0; i < pragmas_array.Length(); i++) {
     pragma ^= pragmas_array.At(i);
     clazz ^= pragma.clazz();
@@ -514,7 +554,11 @@
     }
   }
 
-  return CompoundFromPragma(zone, pragma, is_struct, error);
+  if (is_struct || is_union) {
+    return CompoundFromPragma(zone, pragma, is_struct, error);
+  }
+  ASSERT(is_abi_specific_int);
+  return AbiSpecificFromPragma(zone, pragma, cls, error);
 }
 #endif
 
diff --git a/runtime/vm/compiler/ffi/recognized_method.cc b/runtime/vm/compiler/ffi/recognized_method.cc
index f2fd7b6..323fcc8 100644
--- a/runtime/vm/compiler/ffi/recognized_method.cc
+++ b/runtime/vm/compiler/ffi/recognized_method.cc
@@ -118,6 +118,36 @@
   }
 }
 
+MethodRecognizer::Kind FfiLoad(const NativeType& native_type) {
+  if (native_type.IsPrimitive()) {
+    switch (native_type.AsPrimitive().representation()) {
+#define CASE(type)                                                             \
+  case k##type:                                                                \
+    return MethodRecognizer::kFfiLoad##type;
+      CLASS_LIST_FFI_NUMERIC_FIXED_SIZE(CASE)
+#undef CASE
+      default:
+        break;
+    }
+  }
+  UNIMPLEMENTED();
+}
+
+MethodRecognizer::Kind FfiStore(const NativeType& native_type) {
+  if (native_type.IsPrimitive()) {
+    switch (native_type.AsPrimitive().representation()) {
+#define CASE(type)                                                             \
+  case k##type:                                                                \
+    return MethodRecognizer::kFfiStore##type;
+      CLASS_LIST_FFI_NUMERIC_FIXED_SIZE(CASE)
+#undef CASE
+      default:
+        break;
+    }
+  }
+  UNIMPLEMENTED();
+}
+
 }  // namespace ffi
 
 }  // namespace compiler
diff --git a/runtime/vm/compiler/ffi/recognized_method.h b/runtime/vm/compiler/ffi/recognized_method.h
index 98f4a31..ebb02a15 100644
--- a/runtime/vm/compiler/ffi/recognized_method.h
+++ b/runtime/vm/compiler/ffi/recognized_method.h
@@ -32,6 +32,9 @@
 
 AlignmentType RecognizedMethodAlignment(MethodRecognizer::Kind kind);
 
+MethodRecognizer::Kind FfiLoad(const NativeType& native_type);
+MethodRecognizer::Kind FfiStore(const NativeType& native_type);
+
 }  // namespace ffi
 
 }  // namespace compiler
diff --git a/runtime/vm/compiler/frontend/base_flow_graph_builder.cc b/runtime/vm/compiler/frontend/base_flow_graph_builder.cc
index b37c682..f510129 100644
--- a/runtime/vm/compiler/frontend/base_flow_graph_builder.cc
+++ b/runtime/vm/compiler/frontend/base_flow_graph_builder.cc
@@ -28,11 +28,16 @@
 }
 
 Fragment& Fragment::operator+=(const Fragment& other) {
-  if (entry == NULL) {
+  if (entry == nullptr) {
     entry = other.entry;
     current = other.current;
-  } else if (current != NULL && other.entry != NULL) {
-    current->LinkTo(other.entry);
+  } else if (other.entry != nullptr) {
+    if (current != nullptr) {
+      current->LinkTo(other.entry);
+    }
+    // Although [other.entry] could be unreachable (if this fragment is
+    // closed), there could be a yield continuation point in the middle of
+    // [other] fragment so [other.current] is still reachable.
     current = other.current;
   }
   return *this;
@@ -876,6 +881,19 @@
   return nsm;
 }
 
+Fragment BaseFlowGraphBuilder::ThrowException(TokenPosition position) {
+  Fragment instructions;
+  Value* exception = Pop();
+  instructions += Fragment(new (Z) ThrowInstr(InstructionSource(position),
+                                              GetNextDeoptId(), exception))
+                      .closed();
+  // Use its side effect of leaving a constant on the stack (does not change
+  // the graph).
+  NullConstant();
+
+  return instructions;
+}
+
 Fragment BaseFlowGraphBuilder::AssertBool(TokenPosition position) {
   Value* value = Pop();
   AssertBooleanInstr* instr = new (Z)
@@ -995,14 +1013,23 @@
   ASSERT(signatures.IsInstantiated());
   ASSERT(signatures.Length() == 2);
 
-  const AbstractType& dart_type = AbstractType::Handle(signatures.TypeAt(0));
-  const AbstractType& native_type = AbstractType::Handle(signatures.TypeAt(1));
+  const auto& dart_type =
+      FunctionType::Cast(AbstractType::Handle(signatures.TypeAt(0)));
+  const auto& native_type =
+      FunctionType::Cast(AbstractType::Handle(signatures.TypeAt(1)));
 
-  ASSERT(dart_type.IsFunctionType() && native_type.IsFunctionType());
-  const Function& target =
-      Function::ZoneHandle(compiler::ffi::TrampolineFunction(
-          FunctionType::Cast(dart_type), FunctionType::Cast(native_type),
-          is_leaf));
+  // AbiSpecificTypes can have an incomplete mapping.
+  const char* error = nullptr;
+  compiler::ffi::NativeFunctionTypeFromFunctionType(zone_, native_type, &error);
+  if (error != nullptr) {
+    const auto& language_error = Error::Handle(
+        LanguageError::New(String::Handle(String::New(error, Heap::kOld)),
+                           Report::kError, Heap::kOld));
+    Report::LongJump(language_error);
+  }
+
+  const Function& target = Function::ZoneHandle(
+      compiler::ffi::TrampolineFunction(dart_type, native_type, is_leaf));
 
   Fragment code;
   // Store the pointer in the context, we cannot load the untagged address
@@ -1244,33 +1271,44 @@
 }
 
 Fragment BaseFlowGraphBuilder::RecordCoverage(TokenPosition position) {
+  return RecordCoverageImpl(position, false /** is_branch_coverage **/);
+}
+
+Fragment BaseFlowGraphBuilder::RecordBranchCoverage(TokenPosition position) {
+  return RecordCoverageImpl(position, true /** is_branch_coverage **/);
+}
+
+Fragment BaseFlowGraphBuilder::RecordCoverageImpl(TokenPosition position,
+                                                  bool is_branch_coverage) {
   Fragment instructions;
-  if (SupportsCoverage()) {
-    const intptr_t coverage_index = GetCoverageIndexFor(position);
-    instructions <<= new (Z) RecordCoverageInstr(
-        coverage_array(), coverage_index, InstructionSource(position));
-  }
+  if (!SupportsCoverage()) return instructions;
+  if (!position.IsReal()) return instructions;
+  if (is_branch_coverage && !IG->branch_coverage()) return instructions;
+
+  const intptr_t coverage_index =
+      GetCoverageIndexFor(position.EncodeCoveragePosition(is_branch_coverage));
+  instructions <<= new (Z) RecordCoverageInstr(coverage_array(), coverage_index,
+                                               InstructionSource(position));
   return instructions;
 }
 
-intptr_t BaseFlowGraphBuilder::GetCoverageIndexFor(TokenPosition token_pos) {
+intptr_t BaseFlowGraphBuilder::GetCoverageIndexFor(intptr_t encoded_position) {
   if (coverage_array_.IsNull()) {
-    // We have not yet created coverage_array, this is the first time
-    // we are building the graph for this function. Collect coverage
-    // positions.
+    // We have not yet created coverage_array, this is the first time we are
+    // building the graph for this function. Collect coverage positions.
     for (intptr_t i = 0; i < coverage_array_positions_.length(); i++) {
-      if (coverage_array_positions_.At(i) == token_pos) {
+      if (coverage_array_positions_.At(i) == encoded_position) {
         return 2 * i + 1;
       }
     }
     const auto index = 2 * coverage_array_positions_.length() + 1;
-    coverage_array_positions_.Add(token_pos);
+    coverage_array_positions_.Add(encoded_position);
     return index;
   }
 
   for (intptr_t i = 0; i < coverage_array_.Length(); i += 2) {
-    if (TokenPosition::Deserialize(Smi::Value(
-            static_cast<SmiPtr>(coverage_array_.At(i)))) == token_pos) {
+    if (Smi::Value(static_cast<SmiPtr>(coverage_array_.At(i))) ==
+        encoded_position) {
       return i + 1;
     }
   }
@@ -1294,7 +1332,7 @@
 
   Smi& value = Smi::Handle();
   for (intptr_t i = 0; i < coverage_array_positions_.length(); i++) {
-    value = Smi::New(coverage_array_positions_[i].Serialize());
+    value = Smi::New(coverage_array_positions_[i]);
     coverage_array_.SetAt(2 * i, value);
     value = Smi::New(0);  // no coverage recorded.
     coverage_array_.SetAt(2 * i + 1, value);
diff --git a/runtime/vm/compiler/frontend/base_flow_graph_builder.h b/runtime/vm/compiler/frontend/base_flow_graph_builder.h
index b0597b8..37651ab 100644
--- a/runtime/vm/compiler/frontend/base_flow_graph_builder.h
+++ b/runtime/vm/compiler/frontend/base_flow_graph_builder.h
@@ -166,7 +166,6 @@
 
   const Array& coverage_array() const { return coverage_array_; }
 
-  intptr_t GetCoverageIndexFor(TokenPosition token_pos);
   void FinalizeCoverageArray();
 
   Fragment LoadField(const Field& field, bool calls_initializer);
@@ -349,6 +348,7 @@
   Fragment TestAnyTypeArgs(Fragment present, Fragment absent);
 
   JoinEntryInstr* BuildThrowNoSuchMethod();
+  Fragment ThrowException(TokenPosition position);
 
   Fragment AssertBool(TokenPosition position);
   Fragment BooleanNegate();
@@ -473,6 +473,7 @@
 
   // Records coverage for this position, if the current VM mode supports it.
   Fragment RecordCoverage(TokenPosition position);
+  Fragment RecordBranchCoverage(TokenPosition position);
 
   // Returns whether this function has a saved arguments descriptor array.
   bool has_saved_args_desc_array() {
@@ -487,6 +488,8 @@
 
  protected:
   intptr_t AllocateBlockId() { return ++last_used_block_id_; }
+  Fragment RecordCoverageImpl(TokenPosition position, bool is_branch_coverage);
+  intptr_t GetCoverageIndexFor(intptr_t encoded_position);
 
   const ParsedFunction* parsed_function_;
   const Function& function_;
@@ -507,7 +510,7 @@
   const bool inlining_unchecked_entry_;
   const Array& saved_args_desc_array_;
 
-  GrowableArray<TokenPosition> coverage_array_positions_;
+  GrowableArray<intptr_t> coverage_array_positions_;
   Array& coverage_array_;
 
   friend class StreamingFlowGraphBuilder;
diff --git a/runtime/vm/compiler/frontend/kernel_binary_flowgraph.cc b/runtime/vm/compiler/frontend/kernel_binary_flowgraph.cc
index ccdc992..00c2160 100644
--- a/runtime/vm/compiler/frontend/kernel_binary_flowgraph.cc
+++ b/runtime/vm/compiler/frontend/kernel_binary_flowgraph.cc
@@ -6,6 +6,7 @@
 
 #include "vm/closure_functions_cache.h"
 #include "vm/compiler/ffi/callback.h"
+#include "vm/compiler/ffi/recognized_method.h"
 #include "vm/compiler/frontend/flow_graph_builder.h"  // For dart::FlowGraphBuilder::SimpleInstanceOfType.
 #include "vm/compiler/frontend/prologue_builder.h"
 #include "vm/compiler/jit/compiler.h"
@@ -364,7 +365,7 @@
           intptr_t argument_count;
           instructions += BuildArguments(
               &argument_names, &argument_count,
-              /* positional_parameter_count = */ NULL);  // read arguments.
+              /* positional_parameter_count = */ nullptr);  // read arguments.
           argument_count += 1;
 
           Class& parent_klass = GetSuperOrDie();
@@ -390,7 +391,7 @@
           intptr_t argument_count;
           instructions += BuildArguments(
               &argument_names, &argument_count,
-              /* positional_parameter_count = */ NULL);  // read arguments.
+              /* positional_parameter_count = */ nullptr);  // read arguments.
           argument_count += 1;
 
           const Function& target = Function::ZoneHandle(
@@ -487,7 +488,7 @@
     ASSERT(yield_continuations().is_empty() || !dart_function.IsGeneric());
 
     LocalVariable* fn_type_args = parsed_function()->function_type_arguments();
-    ASSERT(fn_type_args != NULL && closure != NULL);
+    ASSERT(fn_type_args != nullptr && closure != nullptr);
 
     if (dart_function.IsGeneric()) {
       prologue += LoadLocal(fn_type_args);
@@ -527,7 +528,8 @@
 
   // Prepend an entry corresponding to normal entry to the function.
   yield_continuations().InsertAt(
-      0, YieldContinuation(new (Z) DropTempsInstr(0, NULL), kInvalidTryIndex));
+      0,
+      YieldContinuation(new (Z) DropTempsInstr(0, nullptr), kInvalidTryIndex));
   yield_continuations()[0].entry->LinkTo(body.entry);
 
   // Load :await_jump_var into a temporary.
@@ -648,7 +650,7 @@
         ASSERT((function.HasOptionalParameters() &&
                 raw_parameter.owner() == scope) ||
                (!function.HasOptionalParameters() &&
-                raw_parameter.owner() == NULL));
+                raw_parameter.owner() == nullptr));
         ASSERT(!raw_parameter.is_captured());
 
         // Copy the parameter from the stack to the context.
@@ -1017,7 +1019,7 @@
       break;
   }
   UNREACHABLE();
-  return NULL;
+  return nullptr;
 }
 
 void StreamingFlowGraphBuilder::ParseKernelASTFunction() {
@@ -1239,52 +1241,52 @@
   return Fragment();
 }
 
-Fragment StreamingFlowGraphBuilder::BuildStatement() {
+Fragment StreamingFlowGraphBuilder::BuildStatement(TokenPosition* position) {
   intptr_t offset = ReaderOffset();
   Tag tag = ReadTag();  // read tag.
   switch (tag) {
     case kExpressionStatement:
-      return BuildExpressionStatement();
+      return BuildExpressionStatement(position);
     case kBlock:
-      return BuildBlock();
+      return BuildBlock(position);
     case kEmptyStatement:
       return BuildEmptyStatement();
     case kAssertBlock:
-      return BuildAssertBlock();
+      return BuildAssertBlock(position);
     case kAssertStatement:
-      return BuildAssertStatement();
+      return BuildAssertStatement(position);
     case kLabeledStatement:
-      return BuildLabeledStatement();
+      return BuildLabeledStatement(position);
     case kBreakStatement:
-      return BuildBreakStatement();
+      return BuildBreakStatement(position);
     case kWhileStatement:
-      return BuildWhileStatement();
+      return BuildWhileStatement(position);
     case kDoStatement:
-      return BuildDoStatement();
+      return BuildDoStatement(position);
     case kForStatement:
-      return BuildForStatement();
+      return BuildForStatement(position);
     case kForInStatement:
-      return BuildForInStatement(false);
+      return BuildForInStatement(false, position);
     case kAsyncForInStatement:
-      return BuildForInStatement(true);
+      return BuildForInStatement(true, position);
     case kSwitchStatement:
-      return BuildSwitchStatement();
+      return BuildSwitchStatement(position);
     case kContinueSwitchStatement:
-      return BuildContinueSwitchStatement();
+      return BuildContinueSwitchStatement(position);
     case kIfStatement:
-      return BuildIfStatement();
+      return BuildIfStatement(position);
     case kReturnStatement:
-      return BuildReturnStatement();
+      return BuildReturnStatement(position);
     case kTryCatch:
-      return BuildTryCatch();
+      return BuildTryCatch(position);
     case kTryFinally:
-      return BuildTryFinally();
+      return BuildTryFinally(position);
     case kYieldStatement:
-      return BuildYieldStatement();
+      return BuildYieldStatement(position);
     case kVariableDeclaration:
-      return BuildVariableDeclaration();
+      return BuildVariableDeclaration(position);
     case kFunctionDeclaration:
-      return BuildFunctionDeclaration(offset);
+      return BuildFunctionDeclaration(offset, position);
     default:
       ReportUnexpectedTag("statement", tag);
       UNREACHABLE();
@@ -1292,9 +1294,19 @@
   return Fragment();
 }
 
+Fragment StreamingFlowGraphBuilder::BuildStatementWithBranchCoverage(
+    TokenPosition* position) {
+  TokenPosition pos = TokenPosition::kNoSource;
+  Fragment statement = BuildStatement(&pos);
+  if (position != nullptr) *position = pos;
+  Fragment covered_statement = flow_graph_builder_->RecordBranchCoverage(pos);
+  covered_statement += statement;
+  return covered_statement;
+}
+
 void StreamingFlowGraphBuilder::ReportUnexpectedTag(const char* variant,
                                                     Tag tag) {
-  if ((flow_graph_builder_ == NULL) || (parsed_function() == NULL)) {
+  if ((flow_graph_builder_ == nullptr) || (parsed_function() == nullptr)) {
     KernelReaderHelper::ReportUnexpectedTag(variant, tag);
   } else {
     H.ReportError(script_, TokenPosition::kNoSource,
@@ -1974,7 +1986,7 @@
                                                    intptr_t* argument_count,
                                                    intptr_t* positional_count) {
   intptr_t dummy;
-  if (argument_count == NULL) argument_count = &dummy;
+  if (argument_count == nullptr) argument_count = &dummy;
   *argument_count = ReadUInt();  // read arguments count.
 
   // List of types.
@@ -1982,7 +1994,7 @@
 
   {
     AlternativeReadingScope _(&reader_);
-    if (positional_count == NULL) positional_count = &dummy;
+    if (positional_count == nullptr) positional_count = &dummy;
     *positional_count = ReadListLength();  // read length of expression list
   }
   return BuildArgumentsFromActualArguments(argument_names);
@@ -2000,14 +2012,14 @@
 
   // List of named.
   list_length = ReadListLength();  // read list length.
-  if (argument_names != NULL && list_length > 0) {
+  if (argument_names != nullptr && list_length > 0) {
     *argument_names = Array::New(list_length, Heap::kOld);
   }
   for (intptr_t i = 0; i < list_length; ++i) {
     String& name =
         H.DartSymbolObfuscate(ReadStringReference());  // read ith name index.
     instructions += BuildExpression();                 // read ith expression.
-    if (argument_names != NULL) {
+    if (argument_names != nullptr) {
       argument_names->SetAt(i, name);
     }
   }
@@ -2021,7 +2033,7 @@
   // [NoSuchMethodError]s) and only emit [InvalidExpression]s in very special
   // situations (e.g. an invalid annotation).
   TokenPosition pos = ReadPosition();
-  if (position != NULL) *position = pos;
+  if (position != nullptr) *position = pos;
   const String& message = H.DartString(ReadStringReference());
   Tag tag = ReadTag();  // read (first part of) expression.
   if (tag == kSomething) {
@@ -2129,7 +2141,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildVariableSet(TokenPosition* p) {
   TokenPosition position = ReadPosition();  // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   intptr_t variable_kernel_position = ReadUInt();  // read kernel position.
   ReadUInt();  // read relative variable index.
@@ -2139,7 +2151,7 @@
 Fragment StreamingFlowGraphBuilder::BuildVariableSet(uint8_t payload,
                                                      TokenPosition* p) {
   TokenPosition position = ReadPosition();  // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   intptr_t variable_kernel_position = ReadUInt();  // read kernel position.
   return BuildVariableSetImpl(position, variable_kernel_position);
@@ -2629,7 +2641,7 @@
 Fragment StreamingFlowGraphBuilder::BuildSuperPropertyGet(TokenPosition* p) {
   const intptr_t offset = ReaderOffset() - 1;     // Include the tag.
   const TokenPosition position = ReadPosition();  // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   const InferredTypeMetadata result_type =
       inferred_type_metadata_helper_.GetInferredType(offset);
@@ -2705,7 +2717,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildSuperPropertySet(TokenPosition* p) {
   const TokenPosition position = ReadPosition();  // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   Class& klass = GetSuperOrDie();
 
@@ -2772,7 +2784,7 @@
   const intptr_t offset = ReaderOffset() - 1;  // Include the tag.
 
   TokenPosition position = ReadPosition();  // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   const InferredTypeMetadata result_type =
       inferred_type_metadata_helper_.GetInferredType(offset);
@@ -2836,7 +2848,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildStaticSet(TokenPosition* p) {
   TokenPosition position = ReadPosition();  // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   NameIndex target = ReadCanonicalNameReference();  // read target_reference.
   ASSERT(H.IsSetter(target));
@@ -2885,7 +2897,7 @@
   const bool is_invariant = (flags & kInstanceInvocationFlagInvariant) != 0;
 
   const TokenPosition position = ReadPosition();  // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   const DirectCallMetadata direct_call =
       direct_call_metadata_helper_.GetDirectTargetForMethodInvocation(offset);
@@ -2908,7 +2920,7 @@
   Fragment instructions;
 
   intptr_t type_args_len = 0;
-  LocalVariable* type_arguments_temp = NULL;
+  LocalVariable* type_arguments_temp = nullptr;
   {
     AlternativeReadingScope alt(&reader_);
     SkipExpression();                         // skip receiver
@@ -2950,8 +2962,8 @@
     ASSERT(type_args_len == 0);
     // "==" or "!=" with null on either side.
     instructions +=
-        BuildArguments(NULL /* named */, NULL /* arg count */,
-                       NULL /* positional arg count */);  // read arguments.
+        BuildArguments(nullptr /* named */, nullptr /* arg count */,
+                       nullptr /* positional arg count */);  // read arguments.
     SkipInterfaceMemberNameReference();  // read interface_target_reference.
     Token::Kind strict_cmp_kind =
         token_kind == Token::kEQ ? Token::kEQ_STRICT : Token::kNE_STRICT;
@@ -2959,11 +2971,11 @@
            StrictCompare(position, strict_cmp_kind, /*number_check = */ true);
   }
 
-  LocalVariable* receiver_temp = NULL;
+  LocalVariable* receiver_temp = nullptr;
   if (direct_call.check_receiver_for_null_) {
     // Duplicate receiver for CheckNull before it is consumed by PushArgument.
     receiver_temp = MakeTemporary();
-    if (type_arguments_temp != NULL) {
+    if (type_arguments_temp != nullptr) {
       // If call has type arguments then push them before pushing the receiver.
       // The stack will contain:
       //
@@ -3049,10 +3061,10 @@
   }
 
   // Drop temporaries preserving result on the top of the stack.
-  ASSERT((receiver_temp != NULL) || (type_arguments_temp == NULL));
-  if (receiver_temp != NULL) {
-    const intptr_t num_temps =
-        (receiver_temp != NULL ? 1 : 0) + (type_arguments_temp != NULL ? 1 : 0);
+  ASSERT((receiver_temp != nullptr) || (type_arguments_temp == nullptr));
+  if (receiver_temp != nullptr) {
+    const intptr_t num_temps = (receiver_temp != nullptr ? 1 : 0) +
+                               (type_arguments_temp != nullptr ? 1 : 0);
     instructions += DropTempsPreserveTop(num_temps);
   }
 
@@ -3259,7 +3271,7 @@
     TokenPosition* p) {
   const intptr_t offset = ReaderOffset() - 1;     // Include the tag.
   const TokenPosition position = ReadPosition();  // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   const InferredTypeMetadata result_type =
       inferred_type_metadata_helper_.GetInferredType(offset);
@@ -3383,7 +3395,7 @@
     intptr_t argument_count;
     instructions += BuildArguments(
         &argument_names, &argument_count,
-        /* positional_argument_count = */ NULL);  // read arguments.
+        /* positional_argument_count = */ nullptr);  // read arguments.
     ++argument_count;                             // include receiver
     SkipInterfaceMemberNameReference();           // interfaceTargetReference
     return instructions +
@@ -3397,7 +3409,7 @@
 Fragment StreamingFlowGraphBuilder::BuildStaticInvocation(TokenPosition* p) {
   const intptr_t offset = ReaderOffset() - 1;  // Include the tag.
   TokenPosition position = ReadPosition();     // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   const InferredTypeMetadata result_type =
       inferred_type_metadata_helper_.GetInferredType(offset);
@@ -3415,17 +3427,30 @@
   }
 
   const auto recognized_kind = target.recognized_kind();
-  if (recognized_kind == MethodRecognizer::kNativeEffect) {
-    return BuildNativeEffect();
-  } else if (recognized_kind == MethodRecognizer::kFfiAsFunctionInternal) {
-    return BuildFfiAsFunctionInternal();
-  } else if (CompilerState::Current().is_aot() &&
-             recognized_kind == MethodRecognizer::kFfiNativeCallbackFunction) {
-    return BuildFfiNativeCallbackFunction();
+  switch (recognized_kind) {
+    case MethodRecognizer::kNativeEffect:
+      return BuildNativeEffect();
+    case MethodRecognizer::kFfiAsFunctionInternal:
+      return BuildFfiAsFunctionInternal();
+    case MethodRecognizer::kFfiNativeCallbackFunction:
+      if (CompilerState::Current().is_aot()) {
+        return BuildFfiNativeCallbackFunction();
+      }
+      break;
+    case MethodRecognizer::kFfiLoadAbiSpecificInt:
+      return BuildLoadAbiSpecificInt(/*at_index=*/false);
+    case MethodRecognizer::kFfiLoadAbiSpecificIntAtIndex:
+      return BuildLoadAbiSpecificInt(/*at_index=*/true);
+    case MethodRecognizer::kFfiStoreAbiSpecificInt:
+      return BuildStoreAbiSpecificInt(/*at_index=*/false);
+    case MethodRecognizer::kFfiStoreAbiSpecificIntAtIndex:
+      return BuildStoreAbiSpecificInt(/*at_index=*/true);
+    default:
+      break;
   }
 
   Fragment instructions;
-  LocalVariable* instance_variable = NULL;
+  LocalVariable* instance_variable = nullptr;
 
   const bool special_case_unchecked_cast =
       klass.IsTopLevel() && (klass.library() == Library::InternalLibrary()) &&
@@ -3483,11 +3508,11 @@
 
   Array& argument_names = Array::ZoneHandle(Z);
   instructions +=
-      BuildArguments(&argument_names, NULL /* arg count */,
-                     NULL /* positional arg count */);  // read arguments.
+      BuildArguments(&argument_names, nullptr /* arg count */,
+                     nullptr /* positional arg count */);  // read arguments.
   ASSERT(!special_case ||
          target.AreValidArguments(type_args_len, argument_count, argument_names,
-                                  NULL));
+                                  nullptr));
 
   // Special case identical(x, y) call.
   // TODO(27590) consider moving this into the inliner and force inline it
@@ -3514,7 +3539,7 @@
 Fragment StreamingFlowGraphBuilder::BuildConstructorInvocation(
     TokenPosition* p) {
   TokenPosition position = ReadPosition();  // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   NameIndex kernel_name =
       ReadCanonicalNameReference();  // read target_reference.
@@ -3555,18 +3580,18 @@
   intptr_t argument_count;
   instructions += BuildArguments(
       &argument_names, &argument_count,
-      /* positional_argument_count = */ NULL);  // read arguments.
+      /* positional_argument_count = */ nullptr);  // read arguments.
 
   const Function& target = Function::ZoneHandle(
       Z, H.LookupConstructorByKernelConstructor(klass, kernel_name));
   ++argument_count;
   instructions += StaticCall(position, target, argument_count, argument_names,
-                             ICData::kStatic, /* result_type = */ NULL);
+                             ICData::kStatic, /* result_type = */ nullptr);
   return instructions + Drop();
 }
 
 Fragment StreamingFlowGraphBuilder::BuildNot(TokenPosition* position) {
-  if (position != NULL) *position = TokenPosition::kNoSource;
+  if (position != nullptr) *position = TokenPosition::kNoSource;
 
   TokenPosition operand_position = TokenPosition::kNoSource;
   Fragment instructions =
@@ -3664,7 +3689,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildLogicalExpression(
     TokenPosition* position) {
-  if (position != NULL) *position = TokenPosition::kNoSource;
+  if (position != nullptr) *position = TokenPosition::kNoSource;
 
   TestFragment exits;
   exits.true_successor_addresses = new TestFragment::SuccessorAddressArray(2);
@@ -3701,7 +3726,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildConditionalExpression(
     TokenPosition* position) {
-  if (position != NULL) *position = TokenPosition::kNoSource;
+  if (position != nullptr) *position = TokenPosition::kNoSource;
 
   TestFragment condition = TranslateConditionForControl();  // read condition.
 
@@ -3817,7 +3842,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildIsExpression(TokenPosition* p) {
   TokenPosition position = ReadPosition();  // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   if (translation_helper_.info().kernel_binary_version() >= 38) {
     // We do not use the library mode for the type test, which is indicated by
@@ -3870,7 +3895,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildAsExpression(TokenPosition* p) {
   TokenPosition position = ReadPosition();  // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   const uint8_t flags = ReadFlags();  // read flags.
   const bool is_type_error = (flags & kAsExpressionFlagTypeError) != 0;
@@ -3894,7 +3919,7 @@
 }
 
 Fragment StreamingFlowGraphBuilder::BuildTypeLiteral(TokenPosition* position) {
-  if (position != NULL) *position = TokenPosition::kNoSource;
+  if (position != nullptr) *position = TokenPosition::kNoSource;
 
   const AbstractType& type = T.BuildType();  // read type.
   Fragment instructions;
@@ -3918,14 +3943,14 @@
 
 Fragment StreamingFlowGraphBuilder::BuildThisExpression(
     TokenPosition* position) {
-  if (position != NULL) *position = TokenPosition::kNoSource;
+  if (position != nullptr) *position = TokenPosition::kNoSource;
 
   return LoadLocal(parsed_function()->receiver_var());
 }
 
 Fragment StreamingFlowGraphBuilder::BuildRethrow(TokenPosition* p) {
   TokenPosition position = ReadPosition();  // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   Fragment instructions = DebugStepCheck(position);
   instructions += LoadLocal(catch_block()->exception_var());
@@ -3937,7 +3962,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildThrow(TokenPosition* p) {
   TokenPosition position = ReadPosition();  // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   Fragment instructions;
 
@@ -3954,7 +3979,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildListLiteral(TokenPosition* p) {
   TokenPosition position = ReadPosition();  // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   const TypeArguments& type_arguments = T.BuildTypeArguments(1);  // read type.
   intptr_t length = ReadListLength();  // read list length.
@@ -4000,7 +4025,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildMapLiteral(TokenPosition* p) {
   TokenPosition position = ReadPosition();  // read position.
-  if (p != NULL) *p = position;
+  if (p != nullptr) *p = position;
 
   const TypeArguments& type_arguments =
       T.BuildTypeArguments(2);  // read key_type and value_type.
@@ -4057,8 +4082,8 @@
 Fragment StreamingFlowGraphBuilder::BuildLet(TokenPosition* p) {
   const TokenPosition position = ReadPosition();  // read position.
   if (p != nullptr) *p = position;
-  Fragment instructions = BuildVariableDeclaration();  // read variable.
-  instructions += BuildExpression();                   // read body.
+  Fragment instructions = BuildVariableDeclaration(nullptr);  // read variable.
+  instructions += BuildExpression();                          // read body.
   return instructions;
 }
 
@@ -4082,7 +4107,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildBigIntLiteral(
     TokenPosition* position) {
-  if (position != NULL) *position = TokenPosition::kNoSource;
+  if (position != nullptr) *position = TokenPosition::kNoSource;
 
   const String& value =
       H.DartString(ReadStringReference());  // read index into string table.
@@ -4097,7 +4122,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildStringLiteral(
     TokenPosition* position) {
-  if (position != NULL) *position = TokenPosition::kNoSource;
+  if (position != nullptr) *position = TokenPosition::kNoSource;
 
   return Constant(H.DartSymbolPlain(
       ReadStringReference()));  // read index into string table.
@@ -4105,7 +4130,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildIntLiteral(uint8_t payload,
                                                     TokenPosition* position) {
-  if (position != NULL) *position = TokenPosition::kNoSource;
+  if (position != nullptr) *position = TokenPosition::kNoSource;
 
   int64_t value = static_cast<int32_t>(payload) - SpecializedIntLiteralBias;
   return IntConstant(value);
@@ -4113,7 +4138,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildIntLiteral(bool is_negative,
                                                     TokenPosition* position) {
-  if (position != NULL) *position = TokenPosition::kNoSource;
+  if (position != nullptr) *position = TokenPosition::kNoSource;
 
   int64_t value = is_negative ? -static_cast<int64_t>(ReadUInt())
                               : ReadUInt();  // read value.
@@ -4122,7 +4147,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildDoubleLiteral(
     TokenPosition* position) {
-  if (position != NULL) *position = TokenPosition::kNoSource;
+  if (position != nullptr) *position = TokenPosition::kNoSource;
 
   Double& constant = Double::ZoneHandle(
       Z, Double::NewCanonical(ReadDouble()));  // read double.
@@ -4131,20 +4156,20 @@
 
 Fragment StreamingFlowGraphBuilder::BuildBoolLiteral(bool value,
                                                      TokenPosition* position) {
-  if (position != NULL) *position = TokenPosition::kNoSource;
+  if (position != nullptr) *position = TokenPosition::kNoSource;
 
   return Constant(Bool::Get(value));
 }
 
 Fragment StreamingFlowGraphBuilder::BuildNullLiteral(TokenPosition* position) {
-  if (position != NULL) *position = TokenPosition::kNoSource;
+  if (position != nullptr) *position = TokenPosition::kNoSource;
 
   return Constant(Instance::ZoneHandle(Z, Instance::null()));
 }
 
 Fragment StreamingFlowGraphBuilder::BuildFutureNullValue(
     TokenPosition* position) {
-  if (position != NULL) *position = TokenPosition::kNoSource;
+  if (position != nullptr) *position = TokenPosition::kNoSource;
   const Class& future = Class::Handle(Z, IG->object_store()->future_class());
   ASSERT(!future.IsNull());
   const auto& error = future.EnsureIsFinalized(thread());
@@ -4177,7 +4202,7 @@
 
 Fragment StreamingFlowGraphBuilder::BuildPartialTearoffInstantiation(
     TokenPosition* position) {
-  if (position != NULL) *position = TokenPosition::kNoSource;
+  if (position != nullptr) *position = TokenPosition::kNoSource;
 
   // Create a copy of the closure.
 
@@ -4264,20 +4289,24 @@
   return instructions;
 }
 
-Fragment StreamingFlowGraphBuilder::BuildExpressionStatement() {
-  Fragment instructions = BuildExpression();  // read expression.
+Fragment StreamingFlowGraphBuilder::BuildExpressionStatement(
+    TokenPosition* position) {
+  Fragment instructions = BuildExpression(position);  // read expression.
   instructions += Drop();
   return instructions;
 }
 
-Fragment StreamingFlowGraphBuilder::BuildBlock() {
+Fragment StreamingFlowGraphBuilder::BuildBlock(TokenPosition* position) {
   intptr_t offset = ReaderOffset() - 1;  // Include the tag.
 
   Fragment instructions;
 
   instructions += EnterScope(offset);
-  ReadPosition();                           // read file offset.
+  const TokenPosition pos = ReadPosition();  // read file offset.
+  if (position != nullptr) *position = pos;
+
   ReadPosition();                           // read file end offset.
+
   intptr_t list_length = ReadListLength();  // read number of statements.
   for (intptr_t i = 0; i < list_length; ++i) {
     if (instructions.is_open()) {
@@ -4295,7 +4324,7 @@
   return Fragment();
 }
 
-Fragment StreamingFlowGraphBuilder::BuildAssertBlock() {
+Fragment StreamingFlowGraphBuilder::BuildAssertBlock(TokenPosition* position) {
   if (!IG->asserts()) {
     SkipStatementList();
     return Fragment();
@@ -4309,7 +4338,8 @@
   intptr_t list_length = ReadListLength();  // read number of statements.
   for (intptr_t i = 0; i < list_length; ++i) {
     if (instructions.is_open()) {
-      instructions += BuildStatement();  // read ith statement.
+      // read ith statement.
+      instructions += BuildStatement(i == 0 ? position : nullptr);
     } else {
       SkipStatement();  // read ith statement.
     }
@@ -4319,7 +4349,8 @@
   return instructions;
 }
 
-Fragment StreamingFlowGraphBuilder::BuildAssertStatement() {
+Fragment StreamingFlowGraphBuilder::BuildAssertStatement(
+    TokenPosition* position) {
   if (!IG->asserts()) {
     SetOffset(ReaderOffset() - 1);  // Include the tag.
     SkipStatement();                // read this statement.
@@ -4337,7 +4368,7 @@
   //
   // The call to `_AssertionError._evaluateAssertion()` will take care of both
   // and returns a boolean.
-  instructions += BuildExpression();  // read condition.
+  instructions += BuildExpression(position);  // read condition.
 
   const TokenPosition condition_start_offset =
       ReadPosition();  // read condition start offset.
@@ -4382,7 +4413,8 @@
   return Fragment(instructions.entry, then);
 }
 
-Fragment StreamingFlowGraphBuilder::BuildLabeledStatement() {
+Fragment StreamingFlowGraphBuilder::BuildLabeledStatement(
+    TokenPosition* position) {
   // There can be serveral cases:
   //
   //   * the body contains a break
@@ -4395,7 +4427,7 @@
   //    traversed.
 
   BreakableBlock block(flow_graph_builder_);
-  Fragment instructions = BuildStatement();  // read body.
+  Fragment instructions = BuildStatement(position);  // read body.
   if (block.HadJumper()) {
     if (instructions.is_open()) {
       instructions += Goto(block.destination());
@@ -4406,11 +4438,14 @@
   }
 }
 
-Fragment StreamingFlowGraphBuilder::BuildBreakStatement() {
-  TokenPosition position = ReadPosition();  // read position.
+Fragment StreamingFlowGraphBuilder::BuildBreakStatement(
+    TokenPosition* position) {
+  const TokenPosition pos = ReadPosition();  // read position.
+  if (position != nullptr) *position = pos;
+
   intptr_t target_index = ReadUInt();       // read target index.
 
-  TryFinallyBlock* outer_finally = NULL;
+  TryFinallyBlock* outer_finally = nullptr;
   intptr_t target_context_depth = -1;
   JoinEntryInstr* destination = breakable_block()->BreakDestination(
       target_index, &outer_finally, &target_context_depth);
@@ -4418,8 +4453,8 @@
   Fragment instructions;
   // Break statement should pause before manipulation of context, which
   // will possibly cause debugger having incorrect context object.
-  if (NeedsDebugStepCheck(parsed_function()->function(), position)) {
-    instructions += DebugStepCheck(position);
+  if (NeedsDebugStepCheck(parsed_function()->function(), pos)) {
+    instructions += DebugStepCheck(pos);
   }
   instructions +=
       TranslateFinallyFinalizers(outer_finally, target_context_depth);
@@ -4429,12 +4464,15 @@
   return instructions;
 }
 
-Fragment StreamingFlowGraphBuilder::BuildWhileStatement() {
+Fragment StreamingFlowGraphBuilder::BuildWhileStatement(
+    TokenPosition* position) {
   ASSERT(block_expression_depth() == 0);  // no while in block-expr
   loop_depth_inc();
-  const TokenPosition position = ReadPosition();            // read position.
+  const TokenPosition pos = ReadPosition();  // read position.
+  if (position != nullptr) *position = pos;
+
   TestFragment condition = TranslateConditionForControl();  // read condition.
-  const Fragment body = BuildStatement();                   // read body
+  const Fragment body = BuildStatementWithBranchCoverage();  // read body
 
   Fragment body_entry(condition.CreateTrueSuccessor(flow_graph_builder_));
   body_entry += body;
@@ -4446,7 +4484,7 @@
 
     Fragment loop(join);
     ASSERT(B->GetStackDepth() == 0);
-    loop += CheckStackOverflow(position);
+    loop += CheckStackOverflow(pos);
     loop.current->LinkTo(condition.entry);
 
     entry = Goto(join).entry;
@@ -4458,11 +4496,13 @@
   return Fragment(entry, condition.CreateFalseSuccessor(flow_graph_builder_));
 }
 
-Fragment StreamingFlowGraphBuilder::BuildDoStatement() {
+Fragment StreamingFlowGraphBuilder::BuildDoStatement(TokenPosition* position) {
   ASSERT(block_expression_depth() == 0);  // no do-while in block-expr
   loop_depth_inc();
-  const TokenPosition position = ReadPosition();  // read position.
-  Fragment body = BuildStatement();               // read body.
+  const TokenPosition pos = ReadPosition();  // read position.
+  if (position != nullptr) *position = pos;
+
+  Fragment body = BuildStatementWithBranchCoverage();  // read body.
 
   if (body.is_closed()) {
     SkipExpression();  // read condition.
@@ -4475,7 +4515,7 @@
   JoinEntryInstr* join = BuildJoinEntry();
   Fragment loop(join);
   ASSERT(B->GetStackDepth() == 0);
-  loop += CheckStackOverflow(position);
+  loop += CheckStackOverflow(pos);
   loop += body;
   loop <<= condition.entry;
 
@@ -4487,10 +4527,11 @@
       condition.CreateFalseSuccessor(flow_graph_builder_));
 }
 
-Fragment StreamingFlowGraphBuilder::BuildForStatement() {
+Fragment StreamingFlowGraphBuilder::BuildForStatement(TokenPosition* position) {
   intptr_t offset = ReaderOffset() - 1;  // Include the tag.
 
-  const TokenPosition position = ReadPosition();  // read position.
+  const TokenPosition pos = ReadPosition();  // read position.
+  if (position != nullptr) *position = pos;
 
   Fragment declarations;
 
@@ -4501,7 +4542,7 @@
 
   intptr_t list_length = ReadListLength();  // read number of variables.
   for (intptr_t i = 0; i < list_length; ++i) {
-    declarations += BuildVariableDeclaration();  // read ith variable.
+    declarations += BuildVariableDeclaration(nullptr);  // read ith variable.
   }
 
   Tag tag = ReadTag();  // Read first part of condition.
@@ -4525,7 +4566,7 @@
   }
 
   Fragment body(body_entry);
-  body += BuildStatement();  // read body.
+  body += BuildStatementWithBranchCoverage();  // read body.
 
   if (body.is_open()) {
     // We allocated a fresh context before the loop which contains captured
@@ -4543,7 +4584,7 @@
     body += Goto(join);
 
     Fragment loop(join);
-    loop += CheckStackOverflow(position);  // may have non-empty stack
+    loop += CheckStackOverflow(pos);  // may have non-empty stack
     if (condition.entry != nullptr) {
       loop <<= condition.entry;
     } else {
@@ -4566,10 +4607,14 @@
   return loop;
 }
 
-Fragment StreamingFlowGraphBuilder::BuildForInStatement(bool async) {
+Fragment StreamingFlowGraphBuilder::BuildForInStatement(
+    bool async,
+    TokenPosition* position) {
   intptr_t offset = ReaderOffset() - 1;  // Include the tag.
 
-  const TokenPosition position = ReadPosition();  // read position.
+  const TokenPosition pos = ReadPosition();  // read position.
+  if (position != nullptr) *position = pos;
+
   TokenPosition body_position = ReadPosition();   // read body position.
   intptr_t variable_kernel_position = ReaderOffset() + data_program_offset_;
   SkipVariableDeclaration();  // read variable.
@@ -4604,7 +4649,7 @@
   body += StoreLocal(TokenPosition::kNoSource,
                      LookupVariable(variable_kernel_position));
   body += Drop();
-  body += BuildStatement();  // read body.
+  body += BuildStatementWithBranchCoverage();  // read body.
   body += ExitScope(offset);
 
   if (body.is_open()) {
@@ -4613,7 +4658,7 @@
     body += Goto(join);
 
     Fragment loop(join);
-    loop += CheckStackOverflow(position);  // may have non-empty stack
+    loop += CheckStackOverflow(pos);  // may have non-empty stack
     loop += condition;
   } else {
     instructions += condition;
@@ -4624,8 +4669,11 @@
   return Fragment(instructions.entry, loop_exit);
 }
 
-Fragment StreamingFlowGraphBuilder::BuildSwitchStatement() {
-  ReadPosition();  // read position.
+Fragment StreamingFlowGraphBuilder::BuildSwitchStatement(
+    TokenPosition* position) {
+  const TokenPosition pos = ReadPosition();  // read position.
+  if (position != nullptr) *position = pos;
+
   // We need the number of cases. So start by getting that, then go back.
   intptr_t offset = ReaderOffset();
   SkipExpression();                   // temporarily skip condition
@@ -4661,9 +4709,9 @@
     bool is_default = ReadBool();  // read is_default.
     if (is_default) default_case = i;
     Fragment& body_fragment = body_fragments[i] =
-        BuildStatement();  // read body.
+        BuildStatementWithBranchCoverage();  // read body.
 
-    if (body_fragment.entry == NULL) {
+    if (body_fragment.entry == nullptr) {
       // Make a NOP in order to ensure linking works properly.
       body_fragment = NullConstant();
       body_fragment += Drop();
@@ -4750,7 +4798,7 @@
         current_instructions += body_fragments[i];
       }
     } else {
-      JoinEntryInstr* body_join = NULL;
+      JoinEntryInstr* body_join = nullptr;
       if (block.HadJumper(i)) {
         body_join = block.DestinationDirect(i);
         body_fragments[i] = Fragment(body_join) + body_fragments[i];
@@ -4760,19 +4808,19 @@
         TargetEntryInstr* then;
         TargetEntryInstr* otherwise;
 
-        TokenPosition position = ReadPosition();  // read jth position.
+        const TokenPosition pos = ReadPosition();  // read jth position.
         current_instructions += Constant(
             Instance::ZoneHandle(Z, constant_reader_.ReadConstantExpression()));
         current_instructions += LoadLocal(scopes()->switch_variable);
         current_instructions +=
-            InstanceCall(position, Symbols::EqualOperator(), Token::kEQ,
+            InstanceCall(pos, Symbols::EqualOperator(), Token::kEQ,
                          /*argument_count=*/2,
                          /*checked_argument_count=*/2);
         current_instructions += BranchIfTrue(&then, &otherwise, false);
 
         Fragment then_fragment(then);
 
-        if (body_join != NULL) {
+        if (body_join != nullptr) {
           // There are several branches to the body, so we will make a goto to
           // the join block (the real body has already been prepended with a
           // join instruction).
@@ -4816,11 +4864,14 @@
   return Fragment(head_instructions.entry, current_instructions.current);
 }
 
-Fragment StreamingFlowGraphBuilder::BuildContinueSwitchStatement() {
-  TokenPosition position = ReadPosition();  // read position.
+Fragment StreamingFlowGraphBuilder::BuildContinueSwitchStatement(
+    TokenPosition* position) {
+  const TokenPosition pos = ReadPosition();  // read position.
+  if (position != nullptr) *position = pos;
+
   intptr_t target_index = ReadUInt();       // read target index.
 
-  TryFinallyBlock* outer_finally = NULL;
+  TryFinallyBlock* outer_finally = nullptr;
   intptr_t target_context_depth = -1;
   JoinEntryInstr* entry = switch_block()->Destination(
       target_index, &outer_finally, &target_context_depth);
@@ -4829,25 +4880,26 @@
   instructions +=
       TranslateFinallyFinalizers(outer_finally, target_context_depth);
   if (instructions.is_open()) {
-    if (NeedsDebugStepCheck(parsed_function()->function(), position)) {
-      instructions += DebugStepCheck(position);
+    if (NeedsDebugStepCheck(parsed_function()->function(), pos)) {
+      instructions += DebugStepCheck(pos);
     }
     instructions += Goto(entry);
   }
   return instructions;
 }
 
-Fragment StreamingFlowGraphBuilder::BuildIfStatement() {
-  ReadPosition();  // read position.
+Fragment StreamingFlowGraphBuilder::BuildIfStatement(TokenPosition* position) {
+  const TokenPosition pos = ReadPosition();  // read position.
+  if (position != nullptr) *position = pos;
 
   TestFragment condition = TranslateConditionForControl();
 
   Fragment then_fragment(condition.CreateTrueSuccessor(flow_graph_builder_));
-  then_fragment += BuildStatement();  // read then.
+  then_fragment += BuildStatementWithBranchCoverage();  // read then.
 
   Fragment otherwise_fragment(
       condition.CreateFalseSuccessor(flow_graph_builder_));
-  otherwise_fragment += BuildStatement();  // read otherwise.
+  otherwise_fragment += BuildStatementWithBranchCoverage();  // read otherwise.
 
   if (then_fragment.is_open()) {
     if (otherwise_fragment.is_open()) {
@@ -4865,11 +4917,14 @@
   }
 }
 
-Fragment StreamingFlowGraphBuilder::BuildReturnStatement() {
-  TokenPosition position = ReadPosition();  // read position.
-  Tag tag = ReadTag();                      // read first part of expression.
+Fragment StreamingFlowGraphBuilder::BuildReturnStatement(
+    TokenPosition* position) {
+  const TokenPosition pos = ReadPosition();  // read position.
+  if (position != nullptr) *position = pos;
 
-  bool inside_try_finally = try_finally_block() != NULL;
+  Tag tag = ReadTag();  // read first part of expression.
+
+  bool inside_try_finally = try_finally_block() != nullptr;
 
   Fragment instructions = tag == kNothing
                               ? NullConstant()
@@ -4881,10 +4936,10 @@
           scopes()->finally_return_variable;
       ASSERT(finally_return_variable != nullptr);
       const Function& function = parsed_function()->function();
-      if (NeedsDebugStepCheck(function, position)) {
-        instructions += DebugStepCheck(position);
+      if (NeedsDebugStepCheck(function, pos)) {
+        instructions += DebugStepCheck(pos);
       }
-      instructions += StoreLocal(position, finally_return_variable);
+      instructions += StoreLocal(pos, finally_return_variable);
       instructions += Drop();
       const intptr_t target_context_depth =
           finally_return_variable->is_captured()
@@ -4901,7 +4956,7 @@
         B->context_depth_ = saved_context_depth;
       }
     } else {
-      instructions += Return(position);
+      instructions += Return(pos);
     }
   } else {
     Pop();
@@ -4910,7 +4965,7 @@
   return instructions;
 }
 
-Fragment StreamingFlowGraphBuilder::BuildTryCatch() {
+Fragment StreamingFlowGraphBuilder::BuildTryCatch(TokenPosition* position) {
   ASSERT(block_expression_depth() == 0);  // no try-catch in block-expr
   InlineBailout("kernel::FlowgraphBuilder::VisitTryCatch");
 
@@ -4922,7 +4977,7 @@
   try_depth_inc();
   {
     TryCatchBlock block(flow_graph_builder_, try_handler_index);
-    try_body += BuildStatement();  // read body.
+    try_body += BuildStatementWithBranchCoverage(position);  // read body.
     try_body += Goto(after_try);
   }
   try_depth_dec();
@@ -4945,7 +5000,7 @@
   // Fill in the body of the catch.
   for (intptr_t i = 0; i < catch_count; ++i) {
     intptr_t catch_offset = ReaderOffset();          // Catch has no tag.
-    TokenPosition position = ReadPosition();         // read position.
+    TokenPosition pos = ReadPosition();              // read position.
     const AbstractType& type_guard = T.BuildType();  // read guard.
     handler_types.SetAt(i, type_guard);
 
@@ -4975,7 +5030,7 @@
       CatchBlock block(flow_graph_builder_, CurrentException(),
                        CurrentStackTrace(), try_handler_index);
 
-      catch_handler_body += BuildStatement();  // read body.
+      catch_handler_body += BuildStatementWithBranchCoverage();  // read body.
 
       // Note: ExitScope adjusts context_depth_ so even if catch_handler_body
       // is closed we still need to execute ExitScope for its side effect.
@@ -5002,9 +5057,9 @@
 
       catch_body += Constant(type_guard);
 
-      catch_body += InstanceCall(
-          position, Library::PrivateCoreLibName(Symbols::_instanceOf()),
-          Token::kIS, 4);
+      catch_body +=
+          InstanceCall(pos, Library::PrivateCoreLibName(Symbols::_instanceOf()),
+                       Token::kIS, 4);
 
       TargetEntryInstr* catch_entry;
       TargetEntryInstr* next_catch_entry;
@@ -5031,7 +5086,7 @@
   return Fragment(try_body.entry, after_try);
 }
 
-Fragment StreamingFlowGraphBuilder::BuildTryFinally() {
+Fragment StreamingFlowGraphBuilder::BuildTryFinally(TokenPosition* position) {
   ASSERT(block_expression_depth() == 0);  // no try-finally in block-expr
   // Note on streaming:
   // We only stream this TryFinally if we can stream everything inside it,
@@ -5076,7 +5131,7 @@
   {
     TryFinallyBlock tfb(flow_graph_builder_, finalizer_offset);
     TryCatchBlock tcb(flow_graph_builder_, try_handler_index);
-    try_body += BuildStatement();  // read body.
+    try_body += BuildStatementWithBranchCoverage(position);  // read body.
   }
   try_depth_dec();
 
@@ -5089,7 +5144,7 @@
     try_body += Goto(finally_entry);
 
     Fragment finally_body(finally_entry);
-    finally_body += BuildStatement();  // read finalizer.
+    finally_body += BuildStatementWithBranchCoverage();  // read finalizer.
     finally_body += Goto(after_try);
   }
 
@@ -5102,7 +5157,7 @@
                                           /* needs_stacktrace = */ false,
                                           /* is_synthesized = */ true);
   SetOffset(finalizer_offset);
-  finally_body += BuildStatement();  // read finalizer
+  finally_body += BuildStatementWithBranchCoverage();  // read finalizer
   if (finally_body.is_open()) {
     finally_body += LoadLocal(CurrentException());
     finally_body += LoadLocal(CurrentStackTrace());
@@ -5115,10 +5170,12 @@
   return Fragment(try_body.entry, after_try);
 }
 
-Fragment StreamingFlowGraphBuilder::BuildYieldStatement() {
-  TokenPosition position = ReadPosition();  // read position.
-  uint8_t flags = ReadByte();               // read flags.
+Fragment StreamingFlowGraphBuilder::BuildYieldStatement(
+    TokenPosition* position) {
+  const TokenPosition pos = ReadPosition();  // read position.
+  if (position != nullptr) *position = pos;
 
+  uint8_t flags = ReadByte();          // read flags.
   ASSERT(flags == kNativeYieldFlags);  // Must have been desugared.
 
   // Setup yield/continue point:
@@ -5145,11 +5202,11 @@
       StoreLocal(TokenPosition::kNoSource, scopes()->yield_context_variable);
   instructions += Drop();
   instructions += BuildExpression();  // read expression.
-  instructions += Return(position, new_yield_pos);
+  instructions += Return(pos, new_yield_pos);
 
   // Note: DropTempsInstr serves as an anchor instruction. It will not
   // be linked into the resulting graph.
-  DropTempsInstr* anchor = new (Z) DropTempsInstr(0, NULL);
+  DropTempsInstr* anchor = new (Z) DropTempsInstr(0, nullptr);
   yield_continuations().Add(YieldContinuation(anchor, CurrentTryIndex()));
 
   Fragment continuation(instructions.entry, anchor);
@@ -5189,7 +5246,7 @@
     rethrow += LoadLocal(exception_var);
     rethrow += LoadLocal(stack_trace_var);
 
-    rethrow += RethrowException(position, kInvalidTryIndex);
+    rethrow += RethrowException(pos, kInvalidTryIndex);
     Drop();
 
     // Set current to the end of the no_error branch.
@@ -5199,7 +5256,8 @@
   return continuation;
 }
 
-Fragment StreamingFlowGraphBuilder::BuildVariableDeclaration() {
+Fragment StreamingFlowGraphBuilder::BuildVariableDeclaration(
+    TokenPosition* position) {
   intptr_t kernel_position_no_tag = ReaderOffset() + data_program_offset_;
   LocalVariable* variable = LookupVariable(kernel_position_no_tag);
 
@@ -5233,6 +5291,7 @@
   const TokenPosition debug_position = helper.equals_position_.IsReal()
                                            ? helper.equals_position_
                                            : helper.position_;
+  if (position != nullptr) *position = helper.position_;
   if (NeedsDebugStepCheck(stack(), debug_position)) {
     instructions = DebugStepCheck(debug_position) + instructions;
   }
@@ -5241,8 +5300,12 @@
   return instructions;
 }
 
-Fragment StreamingFlowGraphBuilder::BuildFunctionDeclaration(intptr_t offset) {
-  TokenPosition position = ReadPosition();
+Fragment StreamingFlowGraphBuilder::BuildFunctionDeclaration(
+    intptr_t offset,
+    TokenPosition* position) {
+  const TokenPosition pos = ReadPosition();
+  if (position != nullptr) *position = pos;
+
   const intptr_t variable_offset = ReaderOffset() + data_program_offset_;
 
   // Read variable declaration.
@@ -5271,10 +5334,10 @@
 
   helper.ReadUntilExcluding(VariableDeclarationHelper::kEnd);
 
-  Fragment instructions = DebugStepCheck(position);
-  instructions += BuildFunctionNode(position, helper.name_index_,
+  Fragment instructions = DebugStepCheck(pos);
+  instructions += BuildFunctionNode(pos, helper.name_index_,
                                     has_valid_annotation, has_pragma, offset);
-  instructions += StoreLocal(position, LookupVariable(variable_offset));
+  instructions += StoreLocal(pos, LookupVariable(variable_offset));
   instructions += Drop();
   return instructions;
 }
@@ -5478,6 +5541,109 @@
   return code;
 }
 
+static void ReportIfNotNull(const char* error) {
+  if (error != nullptr) {
+    const auto& language_error = Error::Handle(
+        LanguageError::New(String::Handle(String::New(error, Heap::kOld)),
+                           Report::kError, Heap::kOld));
+    Report::LongJump(language_error);
+  }
+}
+
+Fragment StreamingFlowGraphBuilder::BuildLoadAbiSpecificInt(bool at_index) {
+  const intptr_t argument_count = ReadUInt();     // Read argument count.
+  ASSERT(argument_count == 2);                    // TypedDataBase, offset/index
+  const intptr_t list_length = ReadListLength();  // Read types list length.
+  ASSERT(list_length == 1);                       // AbiSpecificInt.
+  // Read types.
+  const TypeArguments& type_arguments = T.BuildTypeArguments(list_length);
+  const AbstractType& type_argument =
+      AbstractType::Handle(type_arguments.TypeAt(0));
+
+  // AbiSpecificTypes can have an incomplete mapping.
+  const char* error = nullptr;
+  const auto* native_type =
+      compiler::ffi::NativeType::FromAbstractType(zone_, type_argument, &error);
+  ReportIfNotNull(error);
+
+  Fragment code;
+  // Read positional argument count.
+  const intptr_t positional_count = ReadListLength();
+  ASSERT(positional_count == 2);
+  code += BuildExpression();  // Argument 1: typedDataBase.
+  code += BuildExpression();  // Argument 2: offsetInBytes or index.
+  if (at_index) {
+    code += IntConstant(native_type->SizeInBytes());
+    code += B->BinaryIntegerOp(Token::kMUL, kTagged, /* truncate= */ true);
+  }
+
+  // Skip (empty) named arguments list.
+  const intptr_t named_args_len = ReadListLength();
+  ASSERT(named_args_len == 0);
+
+  // This call site is not guaranteed to be optimized. So, do a call to the
+  // correct force optimized function instead of compiling the body.
+  MethodRecognizer::Kind kind = compiler::ffi::FfiLoad(*native_type);
+  const char* function_name = MethodRecognizer::KindToFunctionNameCString(kind);
+  const Library& ffi_library = Library::Handle(Z, Library::FfiLibrary());
+  const Function& target = Function::ZoneHandle(
+      Z, ffi_library.LookupFunctionAllowPrivate(
+             String::Handle(Z, String::New(function_name))));
+  Array& argument_names = Array::ZoneHandle(Z);
+  code += StaticCall(TokenPosition::kNoSource, target, argument_count,
+                     argument_names, ICData::kStatic);
+
+  return code;
+}
+
+Fragment StreamingFlowGraphBuilder::BuildStoreAbiSpecificInt(bool at_index) {
+  const intptr_t argument_count = ReadUInt();
+  ASSERT(argument_count == 3);
+  const intptr_t list_length = ReadListLength();
+  ASSERT(list_length == 1);
+  // Read types.
+  const TypeArguments& type_arguments = T.BuildTypeArguments(list_length);
+  const AbstractType& type_argument =
+      AbstractType::Handle(type_arguments.TypeAt(0));
+
+  // AbiSpecificTypes can have an incomplete mapping.
+  const char* error = nullptr;
+  const auto* native_type =
+      compiler::ffi::NativeType::FromAbstractType(zone_, type_argument, &error);
+  ReportIfNotNull(error);
+
+  Fragment code;
+  // Read positional argument count.
+  const intptr_t positional_count = ReadListLength();
+  ASSERT(positional_count == 3);
+  code += BuildExpression();  // Argument 1: typedDataBase.
+  code += BuildExpression();  // Argument 2: offsetInBytes or index.
+  if (at_index) {
+    code += IntConstant(native_type->SizeInBytes());
+    code += B->BinaryIntegerOp(Token::kMUL, kTagged, /* truncate= */ true);
+  }
+  code += BuildExpression();  // Argument 3: value
+
+  // Skip (empty) named arguments list.
+  const intptr_t named_args_len = ReadListLength();
+  ASSERT(named_args_len == 0);
+
+  // This call site is not guaranteed to be optimized. So, do a call to the
+  // correct force optimized function instead of compiling the body.
+  MethodRecognizer::Kind kind = compiler::ffi::FfiStore(*native_type);
+  const char* function_name = MethodRecognizer::KindToFunctionNameCString(kind);
+  const Library& ffi_library = Library::Handle(Z, Library::FfiLibrary());
+  const Function& target = Function::ZoneHandle(
+      Z, ffi_library.LookupFunctionAllowPrivate(
+             String::Handle(Z, String::New(function_name))));
+  ASSERT(!target.IsNull());
+  Array& argument_names = Array::ZoneHandle(Z);
+  code += StaticCall(TokenPosition::kNoSource, target, argument_count,
+                     argument_names, ICData::kStatic);
+
+  return code;
+}
+
 Fragment StreamingFlowGraphBuilder::BuildFfiAsFunctionInternal() {
   const intptr_t argc = ReadUInt();               // Read argument count.
   ASSERT(argc == 2);                              // Pointer, isLeaf.
@@ -5556,6 +5722,11 @@
       ReadListLength();  // Skip (empty) named arguments list.
   ASSERT(named_args_len == 0);
 
+  // AbiSpecificTypes can have an incomplete mapping.
+  const char* error = nullptr;
+  compiler::ffi::NativeFunctionTypeFromFunctionType(zone_, native_sig, &error);
+  ReportIfNotNull(error);
+
   const Function& result =
       Function::ZoneHandle(Z, compiler::ffi::NativeCallbackFunction(
                                   native_sig, target, exceptional_return));
diff --git a/runtime/vm/compiler/frontend/kernel_binary_flowgraph.h b/runtime/vm/compiler/frontend/kernel_binary_flowgraph.h
index 47ed58b..8fe4c5c 100644
--- a/runtime/vm/compiler/frontend/kernel_binary_flowgraph.h
+++ b/runtime/vm/compiler/frontend/kernel_binary_flowgraph.h
@@ -68,8 +68,9 @@
   Fragment BuildInitializers(const Class& parent_class);
   FlowGraph* BuildGraphOfFunction(bool constructor);
 
-  Fragment BuildExpression(TokenPosition* position = NULL);
-  Fragment BuildStatement();
+  Fragment BuildExpression(TokenPosition* position = nullptr);
+  Fragment BuildStatement(TokenPosition* position = nullptr);
+  Fragment BuildStatementWithBranchCoverage(TokenPosition* position = nullptr);
 
   // Kernel offset:
   //   start of function expression -> end of function body statement
@@ -178,7 +179,7 @@
                       intptr_t argument_count,
                       const Array& argument_names,
                       ICData::RebindRule rebind_rule,
-                      const InferredTypeMetadata* result_type = NULL,
+                      const InferredTypeMetadata* result_type = nullptr,
                       intptr_t type_args_len = 0,
                       bool use_unchecked_entry = false);
   Fragment InstanceCall(TokenPosition position,
@@ -333,26 +334,26 @@
   Fragment BuildLibraryPrefixAction(TokenPosition* position,
                                     const String& selector);
 
-  Fragment BuildExpressionStatement();
-  Fragment BuildBlock();
+  Fragment BuildExpressionStatement(TokenPosition* position);
+  Fragment BuildBlock(TokenPosition* position);
   Fragment BuildEmptyStatement();
-  Fragment BuildAssertBlock();
-  Fragment BuildAssertStatement();
-  Fragment BuildLabeledStatement();
-  Fragment BuildBreakStatement();
-  Fragment BuildWhileStatement();
-  Fragment BuildDoStatement();
-  Fragment BuildForStatement();
-  Fragment BuildForInStatement(bool async);
-  Fragment BuildSwitchStatement();
-  Fragment BuildContinueSwitchStatement();
-  Fragment BuildIfStatement();
-  Fragment BuildReturnStatement();
-  Fragment BuildTryCatch();
-  Fragment BuildTryFinally();
-  Fragment BuildYieldStatement();
-  Fragment BuildVariableDeclaration();
-  Fragment BuildFunctionDeclaration(intptr_t offset);
+  Fragment BuildAssertBlock(TokenPosition* position);
+  Fragment BuildAssertStatement(TokenPosition* position);
+  Fragment BuildLabeledStatement(TokenPosition* position);
+  Fragment BuildBreakStatement(TokenPosition* position);
+  Fragment BuildWhileStatement(TokenPosition* position);
+  Fragment BuildDoStatement(TokenPosition* position);
+  Fragment BuildForStatement(TokenPosition* position);
+  Fragment BuildForInStatement(bool async, TokenPosition* position);
+  Fragment BuildSwitchStatement(TokenPosition* position);
+  Fragment BuildContinueSwitchStatement(TokenPosition* position);
+  Fragment BuildIfStatement(TokenPosition* position);
+  Fragment BuildReturnStatement(TokenPosition* position);
+  Fragment BuildTryCatch(TokenPosition* position);
+  Fragment BuildTryFinally(TokenPosition* position);
+  Fragment BuildYieldStatement(TokenPosition* position);
+  Fragment BuildVariableDeclaration(TokenPosition* position);
+  Fragment BuildFunctionDeclaration(intptr_t offset, TokenPosition* position);
   Fragment BuildFunctionNode(TokenPosition parent_position,
                              StringIndex name_index,
                              bool has_valid_annotation,
@@ -362,6 +363,15 @@
   // Build flow graph for '_nativeEffect'.
   Fragment BuildNativeEffect();
 
+  // Build flow graph for '_loadAbiSpecificInt' and
+  // '_loadAbiSpecificIntAtIndex', '_storeAbiSpecificInt', and
+  // '_storeAbiSpecificIntAtIndex' call sites.
+  //
+  // The second argument is either offsetInBytes (at_index==false), or
+  // index (at_index==true).
+  Fragment BuildLoadAbiSpecificInt(bool at_index);
+  Fragment BuildStoreAbiSpecificInt(bool at_index);
+
   // Build FG for '_asFunctionInternal'. Reads an Arguments from the
   // Kernel buffer and pushes the resulting closure.
   Fragment BuildFfiAsFunctionInternal();
diff --git a/runtime/vm/compiler/frontend/kernel_to_il.cc b/runtime/vm/compiler/frontend/kernel_to_il.cc
index 2b7346a..dba179a 100644
--- a/runtime/vm/compiler/frontend/kernel_to_il.cc
+++ b/runtime/vm/compiler/frontend/kernel_to_il.cc
@@ -402,19 +402,6 @@
   return body;
 }
 
-Fragment FlowGraphBuilder::ThrowException(TokenPosition position) {
-  Fragment instructions;
-  Value* exception = Pop();
-  instructions += Fragment(new (Z) ThrowInstr(InstructionSource(position),
-                                              GetNextDeoptId(), exception))
-                      .closed();
-  // Use its side effect of leaving a constant on the stack (does not change
-  // the graph).
-  NullConstant();
-
-  return instructions;
-}
-
 Fragment FlowGraphBuilder::RethrowException(TokenPosition position,
                                             int catch_try_index) {
   Fragment instructions;
@@ -940,7 +927,7 @@
     case MethodRecognizer::kDoubleFloorToInt:
       if (!FlowGraphCompiler::SupportsUnboxedDoubles()) return false;
 #if defined(TARGET_ARCH_X64)
-      return CompilerState::Current().is_aot();
+      return CompilerState::Current().is_aot() || FLAG_target_unknown_cpu;
 #elif defined(TARGET_ARCH_ARM64)
       return true;
 #else
@@ -4491,6 +4478,8 @@
   const char* error = nullptr;
   const auto marshaller_ptr =
       compiler::ffi::CallMarshaller::FromFunction(Z, function, &error);
+  // AbiSpecific integers can be incomplete causing us to not know the calling
+  // convention. However, this is caught in asFunction in both JIT/AOT.
   RELEASE_ASSERT(error == nullptr);
   RELEASE_ASSERT(marshaller_ptr != nullptr);
   const auto& marshaller = *marshaller_ptr;
@@ -4642,6 +4631,8 @@
   const char* error = nullptr;
   const auto marshaller_ptr =
       compiler::ffi::CallbackMarshaller::FromFunction(Z, function, &error);
+  // AbiSpecific integers can be incomplete causing us to not know the calling
+  // convention. However, this is caught fromFunction in both JIT/AOT.
   RELEASE_ASSERT(error == nullptr);
   RELEASE_ASSERT(marshaller_ptr != nullptr);
   const auto& marshaller = *marshaller_ptr;
diff --git a/runtime/vm/compiler/frontend/kernel_to_il.h b/runtime/vm/compiler/frontend/kernel_to_il.h
index 42573d0..cb66e59 100644
--- a/runtime/vm/compiler/frontend/kernel_to_il.h
+++ b/runtime/vm/compiler/frontend/kernel_to_il.h
@@ -196,7 +196,6 @@
 
   Fragment FfiCall(const compiler::ffi::CallMarshaller& marshaller);
 
-  Fragment ThrowException(TokenPosition position);
   Fragment RethrowException(TokenPosition position, int catch_try_index);
   Fragment LoadLocal(LocalVariable* variable);
   Fragment IndirectGoto(intptr_t target_count);
diff --git a/runtime/vm/compiler/frontend/kernel_translation_helper.h b/runtime/vm/compiler/frontend/kernel_translation_helper.h
index cfe75b0..35b2647 100644
--- a/runtime/vm/compiler/frontend/kernel_translation_helper.h
+++ b/runtime/vm/compiler/frontend/kernel_translation_helper.h
@@ -716,6 +716,7 @@
     kIsEliminatedMixin = 1 << 3,
     kFlagMixinDeclaration = 1 << 4,
     kHasConstConstructor = 1 << 5,
+    kIsMacro = 1 << 6,
   };
 
   explicit ClassHelper(KernelReaderHelper* helper)
diff --git a/runtime/vm/compiler/graph_intrinsifier.cc b/runtime/vm/compiler/graph_intrinsifier.cc
index a0da87b..18abb34 100644
--- a/runtime/vm/compiler/graph_intrinsifier.cc
+++ b/runtime/vm/compiler/graph_intrinsifier.cc
@@ -966,20 +966,10 @@
 }
 
 bool GraphIntrinsifier::Build_Integer_mod(FlowGraph* flow_graph) {
-#if defined(TARGET_ARCH_ARM)
-  if (!TargetCPUFeatures::can_divide()) {
-    return false;
-  }
-#endif
   return BuildBinarySmiOp(flow_graph, Token::kMOD);
 }
 
 bool GraphIntrinsifier::Build_Integer_truncDivide(FlowGraph* flow_graph) {
-#if defined(TARGET_ARCH_ARM)
-  if (!TargetCPUFeatures::can_divide()) {
-    return false;
-  }
-#endif
   return BuildBinarySmiOp(flow_graph, Token::kTRUNCDIV);
 }
 
diff --git a/runtime/vm/compiler/intrinsifier.cc b/runtime/vm/compiler/intrinsifier.cc
index 4ba80d9f..072e8ca 100644
--- a/runtime/vm/compiler/intrinsifier.cc
+++ b/runtime/vm/compiler/intrinsifier.cc
@@ -275,9 +275,7 @@
   // identity hash is not stored in the header of the object.  We
   // therefore don't intrinsify them, falling back on the native C++
   // implementations.
-  if (function.recognized_kind() == MethodRecognizer::kObject_getHash ||
-      function.recognized_kind() ==
-          MethodRecognizer::kObject_setHashIfNotSetYet) {
+  if (function.recognized_kind() == MethodRecognizer::kObject_getHash) {
     return false;
   }
 #endif
diff --git a/runtime/vm/compiler/method_recognizer.cc b/runtime/vm/compiler/method_recognizer.cc
index af01254..d847251 100644
--- a/runtime/vm/compiler/method_recognizer.cc
+++ b/runtime/vm/compiler/method_recognizer.cc
@@ -197,6 +197,12 @@
   return "?";
 }
 
+const char* MethodRecognizer::KindToFunctionNameCString(Kind kind) {
+  if (kind >= kUnknown && kind < kNumRecognizedMethods)
+    return recognized_methods[kind].function_name;
+  return "?";
+}
+
 // Is this method marked with the vm:recognized pragma?
 bool MethodRecognizer::IsMarkedAsRecognized(const Function& function,
                                             const char* kind) {
diff --git a/runtime/vm/compiler/method_recognizer.h b/runtime/vm/compiler/method_recognizer.h
index e9a1067..3ea4247 100644
--- a/runtime/vm/compiler/method_recognizer.h
+++ b/runtime/vm/compiler/method_recognizer.h
@@ -52,6 +52,7 @@
 
   static intptr_t MethodKindToReceiverCid(Kind kind);
   static const char* KindToCString(Kind kind);
+  static const char* KindToFunctionNameCString(Kind kind);
 
   static bool IsMarkedAsRecognized(const Function& function,
                                    const char* kind = nullptr);
diff --git a/runtime/vm/compiler/recognized_methods_list.h b/runtime/vm/compiler/recognized_methods_list.h
index 2d60271..5cb46fc 100644
--- a/runtime/vm/compiler/recognized_methods_list.h
+++ b/runtime/vm/compiler/recognized_methods_list.h
@@ -191,28 +191,32 @@
   V(::, _asFunctionInternal, FfiAsFunctionInternal, 0x92ae104f)                \
   V(::, _nativeCallbackFunction, FfiNativeCallbackFunction, 0x3ff5ae9c)        \
   V(::, _nativeEffect, NativeEffect, 0x61e00b59)                               \
-  V(::, _loadInt8, FfiLoadInt8, 0x0f04dfd6)                                    \
-  V(::, _loadInt16, FfiLoadInt16, 0xec44312d)                                  \
-  V(::, _loadInt32, FfiLoadInt32, 0xee223fc3)                                  \
-  V(::, _loadInt64, FfiLoadInt64, 0xdeefbfa3)                                  \
-  V(::, _loadUint8, FfiLoadUint8, 0xe14e1cd1)                                  \
-  V(::, _loadUint16, FfiLoadUint16, 0x0cd65cea)                                \
-  V(::, _loadUint32, FfiLoadUint32, 0xf66e9055)                                \
-  V(::, _loadUint64, FfiLoadUint64, 0x0505fdcc)                                \
+  V(::, _loadAbiSpecificInt, FfiLoadAbiSpecificInt, 0x7807e872)                \
+  V(::, _loadAbiSpecificIntAtIndex, FfiLoadAbiSpecificIntAtIndex, 0x6aa4cab4)  \
+  V(::, _loadInt8, FfiLoadInt8, 0x0f04e397)                                    \
+  V(::, _loadInt16, FfiLoadInt16, 0xec4434ee)                                  \
+  V(::, _loadInt32, FfiLoadInt32, 0xee224384)                                  \
+  V(::, _loadInt64, FfiLoadInt64, 0xdeefc364)                                  \
+  V(::, _loadUint8, FfiLoadUint8, 0xe14e2092)                                  \
+  V(::, _loadUint16, FfiLoadUint16, 0x0cd660ab)                                \
+  V(::, _loadUint32, FfiLoadUint32, 0xf66e9416)                                \
+  V(::, _loadUint64, FfiLoadUint64, 0x0506018d)                                \
   V(::, _loadIntPtr, FfiLoadIntPtr, 0xebd9b43e)                                \
   V(::, _loadFloat, FfiLoadFloat, 0xf8d9845d)                                  \
   V(::, _loadFloatUnaligned, FfiLoadFloatUnaligned, 0xc8c8dfff)                \
   V(::, _loadDouble, FfiLoadDouble, 0xf70cc619)                                \
   V(::, _loadDoubleUnaligned, FfiLoadDoubleUnaligned, 0xc99ebd39)              \
   V(::, _loadPointer, FfiLoadPointer, 0x4e79d0fc)                              \
-  V(::, _storeInt8, FfiStoreInt8, 0xdf50af0c)                                  \
-  V(::, _storeInt16, FfiStoreInt16, 0xd84df332)                                \
-  V(::, _storeInt32, FfiStoreInt32, 0xfbe62c5d)                                \
-  V(::, _storeInt64, FfiStoreInt64, 0xf1d40d7a)                                \
-  V(::, _storeUint8, FfiStoreUint8, 0x056dd2f6)                                \
-  V(::, _storeUint16, FfiStoreUint16, 0xe2fdaade)                              \
-  V(::, _storeUint32, FfiStoreUint32, 0xe5d7e8c5)                              \
-  V(::, _storeUint64, FfiStoreUint64, 0xe2d93239)                              \
+  V(::, _storeAbiSpecificInt, FfiStoreAbiSpecificInt, 0xc70954c0)              \
+  V(::, _storeAbiSpecificIntAtIndex, FfiStoreAbiSpecificIntAtIndex, 0xc64efe4b)\
+  V(::, _storeInt8, FfiStoreInt8, 0xdf50b2cd)                                  \
+  V(::, _storeInt16, FfiStoreInt16, 0xd84df6f3)                                \
+  V(::, _storeInt32, FfiStoreInt32, 0xfbe6301e)                                \
+  V(::, _storeInt64, FfiStoreInt64, 0xf1d4113b)                                \
+  V(::, _storeUint8, FfiStoreUint8, 0x056dd6b7)                                \
+  V(::, _storeUint16, FfiStoreUint16, 0xe2fdae9f)                              \
+  V(::, _storeUint32, FfiStoreUint32, 0xe5d7ec86)                              \
+  V(::, _storeUint64, FfiStoreUint64, 0xe2d935fa)                              \
   V(::, _storeIntPtr, FfiStoreIntPtr, 0x080266a8)                              \
   V(::, _storeFloat, FfiStoreFloat, 0x6484f07e)                                \
   V(::, _storeFloatUnaligned, FfiStoreFloatUnaligned, 0x600a9203)              \
@@ -290,7 +294,6 @@
   V(_FunctionType, get:hashCode, FunctionType_getHashCode, 0x75e0d454)         \
   V(_FunctionType, ==, FunctionType_equality, 0x465868ae)                      \
   V(::, _getHash, Object_getHash, 0xc60ff758)                                  \
-  V(::, _setHashIfNotSetYet, Object_setHashIfNotSetYet, 0x4e17c2f5)            \
 
 #define CORE_INTEGER_LIB_INTRINSIC_LIST(V)                                     \
   V(_IntegerImplementation, >, Integer_greaterThan, 0xf741693b)                \
diff --git a/runtime/vm/compiler/runtime_api.cc b/runtime/vm/compiler/runtime_api.cc
index b1943f6..bc2daf8 100644
--- a/runtime/vm/compiler/runtime_api.cc
+++ b/runtime/vm/compiler/runtime_api.cc
@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+#include "platform/thread_sanitizer.h"
+
 #include "vm/compiler/runtime_api.h"
 
 #include "vm/object.h"
@@ -97,7 +99,7 @@
 
 intptr_t ObjectHash(const Object& obj) {
   if (obj.IsNull()) {
-    return 2011;
+    return kNullIdentityHash;
   }
   if (obj.IsInstance()) {
     return Instance::Cast(obj).CanonicalizeHash();
diff --git a/runtime/vm/compiler/runtime_api.h b/runtime/vm/compiler/runtime_api.h
index 5ce613d..c7fd307 100644
--- a/runtime/vm/compiler/runtime_api.h
+++ b/runtime/vm/compiler/runtime_api.h
@@ -19,7 +19,9 @@
 // in compiler::target namespace.
 
 #include "platform/globals.h"
+#include "platform/thread_sanitizer.h"
 #include "platform/utils.h"
+
 #include "vm/allocation.h"
 #include "vm/bitfield.h"
 #include "vm/bss_relocs.h"
@@ -889,10 +891,14 @@
 
 class CompressedStackMaps : public AllStatic {
  public:
-  static word HeaderSize();
+  static word HeaderSize() { return ObjectHeaderSize() + PayloadHeaderSize(); }
   static word InstanceSize();
   static word InstanceSize(word payload_size);
   FINAL_CLASS();
+
+ private:
+  static word ObjectHeaderSize();
+  static word PayloadHeaderSize();
 };
 
 class LocalVarDescriptors : public AllStatic {
@@ -1059,6 +1065,15 @@
   FINAL_CLASS();
 };
 
+class TsanUtils : public AllStatic {
+ public:
+  static word setjmp_function_offset();
+  static word setjmp_buffer_offset();
+  static word exception_pc_offset();
+  static word exception_sp_offset();
+  static word exception_fp_offset();
+};
+
 class Thread : public AllStatic {
  public:
   static word api_top_scope_offset();
@@ -1122,6 +1137,8 @@
 
   static word callback_code_offset();
   static word callback_stack_return_offset();
+  static word tsan_utils_offset();
+  static word jump_to_frame_entry_point_offset();
 
   static word AllocateArray_entry_point_offset();
   static word write_barrier_code_offset();
@@ -1179,6 +1196,8 @@
   THREAD_XMM_CONSTANT_LIST(DECLARE_CONSTANT_OFFSET_GETTER)
 #undef DECLARE_CONSTANT_OFFSET_GETTER
 
+  static word random_offset();
+
   static word OffsetFromThread(const dart::Object& object);
   static intptr_t OffsetFromThread(const dart::RuntimeEntry* runtime_entry);
 };
diff --git a/runtime/vm/compiler/runtime_offsets_extracted.h b/runtime/vm/compiler/runtime_offsets_extracted.h
index 4ade729..5d764cf 100644
--- a/runtime/vm/compiler/runtime_offsets_extracted.h
+++ b/runtime/vm/compiler/runtime_offsets_extracted.h
@@ -39,10 +39,6 @@
     ExceptionHandlers_elements_start_offset = 12;
 static constexpr dart::compiler::target::word ExceptionHandlers_element_size =
     12;
-static constexpr dart::compiler::target::word
-    InstructionsTable_elements_start_offset = 20;
-static constexpr dart::compiler::target::word InstructionsTable_element_size =
-    4;
 static constexpr dart::compiler::target::word ObjectPool_elements_start_offset =
     8;
 static constexpr dart::compiler::target::word ObjectPool_element_size = 4;
@@ -246,11 +242,11 @@
 static constexpr dart::compiler::target::word String_length_offset = 4;
 static constexpr dart::compiler::target::word SubtypeTestCache_cache_offset = 4;
 static constexpr dart::compiler::target::word
-    Thread_AllocateArray_entry_point_offset = 376;
+    Thread_AllocateArray_entry_point_offset = 380;
 static constexpr dart::compiler::target::word Thread_active_exception_offset =
-    748;
-static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
     752;
+static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
+    756;
 static constexpr dart::compiler::target::word
     Thread_array_write_barrier_code_offset = 128;
 static constexpr dart::compiler::target::word
@@ -275,22 +271,22 @@
     Thread_allocate_object_slow_entry_point_offset = 296;
 static constexpr dart::compiler::target::word
     Thread_allocate_object_slow_stub_offset = 204;
-static constexpr dart::compiler::target::word Thread_api_top_scope_offset = 788;
+static constexpr dart::compiler::target::word Thread_api_top_scope_offset = 792;
 static constexpr dart::compiler::target::word
-    Thread_auto_scope_native_wrapper_entry_point_offset = 340;
+    Thread_auto_scope_native_wrapper_entry_point_offset = 344;
 static constexpr dart::compiler::target::word Thread_bool_false_offset = 120;
 static constexpr dart::compiler::target::word Thread_bool_true_offset = 116;
 static constexpr dart::compiler::target::word
-    Thread_bootstrap_native_wrapper_entry_point_offset = 332;
+    Thread_bootstrap_native_wrapper_entry_point_offset = 336;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_entry_point_offset = 276;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_stub_offset = 144;
-static constexpr dart::compiler::target::word Thread_dart_stream_offset = 800;
+static constexpr dart::compiler::target::word Thread_dart_stream_offset = 816;
 static constexpr dart::compiler::target::word
     Thread_dispatch_table_array_offset = 44;
 static constexpr dart::compiler::target::word
-    Thread_double_truncate_round_supported_offset = 792;
+    Thread_double_truncate_round_supported_offset = 796;
 static constexpr dart::compiler::target::word Thread_optimize_entry_offset =
     316;
 static constexpr dart::compiler::target::word Thread_optimize_stub_offset = 232;
@@ -299,14 +295,14 @@
 static constexpr dart::compiler::target::word Thread_deoptimize_stub_offset =
     236;
 static constexpr dart::compiler::target::word Thread_double_abs_address_offset =
-    356;
+    360;
 static constexpr dart::compiler::target::word
-    Thread_double_negate_address_offset = 352;
+    Thread_double_negate_address_offset = 356;
 static constexpr dart::compiler::target::word Thread_end_offset = 52;
 static constexpr dart::compiler::target::word
     Thread_enter_safepoint_stub_offset = 256;
 static constexpr dart::compiler::target::word Thread_execution_state_offset =
-    768;
+    772;
 static constexpr dart::compiler::target::word
     Thread_exit_safepoint_stub_offset = 260;
 static constexpr dart::compiler::target::word
@@ -318,21 +314,21 @@
 static constexpr dart::compiler::target::word
     Thread_fix_callers_target_code_offset = 132;
 static constexpr dart::compiler::target::word
-    Thread_float_absolute_address_offset = 368;
+    Thread_float_absolute_address_offset = 372;
 static constexpr dart::compiler::target::word
-    Thread_float_negate_address_offset = 364;
+    Thread_float_negate_address_offset = 368;
 static constexpr dart::compiler::target::word Thread_float_not_address_offset =
-    360;
+    364;
 static constexpr dart::compiler::target::word
-    Thread_float_zerow_address_offset = 372;
+    Thread_float_zerow_address_offset = 376;
 static constexpr dart::compiler::target::word Thread_global_object_pool_offset =
-    756;
+    760;
 static constexpr dart::compiler::target::word
     Thread_invoke_dart_code_stub_offset = 140;
 static constexpr dart::compiler::target::word Thread_exit_through_ffi_offset =
-    784;
+    788;
 static constexpr dart::compiler::target::word Thread_isolate_offset = 40;
-static constexpr dart::compiler::target::word Thread_isolate_group_offset = 804;
+static constexpr dart::compiler::target::word Thread_isolate_group_offset = 820;
 static constexpr dart::compiler::target::word Thread_field_table_values_offset =
     64;
 static constexpr dart::compiler::target::word
@@ -350,7 +346,7 @@
 static constexpr dart::compiler::target::word
     Thread_switchable_call_miss_stub_offset = 216;
 static constexpr dart::compiler::target::word
-    Thread_no_scope_native_wrapper_entry_point_offset = 336;
+    Thread_no_scope_native_wrapper_entry_point_offset = 340;
 static constexpr dart::compiler::target::word
     Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 152;
 static constexpr dart::compiler::target::word
@@ -373,16 +369,16 @@
     Thread_range_error_shared_without_fpu_regs_stub_offset = 180;
 static constexpr dart::compiler::target::word Thread_object_null_offset = 112;
 static constexpr dart::compiler::target::word
-    Thread_predefined_symbols_address_offset = 344;
-static constexpr dart::compiler::target::word Thread_resume_pc_offset = 760;
+    Thread_predefined_symbols_address_offset = 348;
+static constexpr dart::compiler::target::word Thread_resume_pc_offset = 764;
 static constexpr dart::compiler::target::word
-    Thread_saved_shadow_call_stack_offset = 764;
+    Thread_saved_shadow_call_stack_offset = 768;
 static constexpr dart::compiler::target::word Thread_safepoint_state_offset =
-    772;
+    776;
 static constexpr dart::compiler::target::word
     Thread_slow_type_test_stub_offset = 248;
 static constexpr dart::compiler::target::word
-    Thread_slow_type_test_entry_point_offset = 328;
+    Thread_slow_type_test_entry_point_offset = 332;
 static constexpr dart::compiler::target::word Thread_stack_limit_offset = 28;
 static constexpr dart::compiler::target::word Thread_saved_stack_limit_offset =
     56;
@@ -414,9 +410,22 @@
 static constexpr dart::compiler::target::word Thread_write_barrier_mask_offset =
     32;
 static constexpr dart::compiler::target::word Thread_heap_base_offset = 36;
-static constexpr dart::compiler::target::word Thread_callback_code_offset = 776;
+static constexpr dart::compiler::target::word Thread_callback_code_offset = 780;
 static constexpr dart::compiler::target::word
-    Thread_callback_stack_return_offset = 780;
+    Thread_callback_stack_return_offset = 784;
+static constexpr dart::compiler::target::word Thread_random_offset = 800;
+static constexpr dart::compiler::target::word
+    Thread_jump_to_frame_entry_point_offset = 328;
+static constexpr dart::compiler::target::word Thread_tsan_utils_offset = 808;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_function_offset =
+    0;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_buffer_offset =
+    4;
+static constexpr dart::compiler::target::word TsanUtils_exception_pc_offset = 8;
+static constexpr dart::compiler::target::word TsanUtils_exception_sp_offset =
+    12;
+static constexpr dart::compiler::target::word TsanUtils_exception_fp_offset =
+    16;
 static constexpr dart::compiler::target::word TimelineStream_enabled_offset = 8;
 static constexpr dart::compiler::target::word TwoByteString_data_offset = 12;
 static constexpr dart::compiler::target::word Type_arguments_offset = 12;
@@ -476,7 +485,7 @@
     4, 12, 8, 16};
 static constexpr dart::compiler::target::word
     Thread_write_barrier_wrappers_thread_offset[] = {
-        716, 720, 724, 728, 732, -1, 736, -1, 740, 744, -1, -1, -1, -1, -1, -1};
+        720, 724, 728, 732, 736, -1, 740, -1, 744, 748, -1, -1, -1, -1, -1, -1};
 static constexpr dart::compiler::target::word AbstractType_InstanceSize = 12;
 static constexpr dart::compiler::target::word ApiError_InstanceSize = 8;
 static constexpr dart::compiler::target::word Array_header_size = 12;
@@ -486,8 +495,10 @@
 static constexpr dart::compiler::target::word Closure_InstanceSize = 28;
 static constexpr dart::compiler::target::word ClosureData_InstanceSize = 20;
 static constexpr dart::compiler::target::word CodeSourceMap_HeaderSize = 8;
-static constexpr dart::compiler::target::word CompressedStackMaps_HeaderSize =
-    8;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_ObjectHeaderSize = 4;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word Context_header_size = 12;
 static constexpr dart::compiler::target::word Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word DynamicLibrary_InstanceSize = 8;
@@ -513,6 +524,8 @@
     8;
 static constexpr dart::compiler::target::word
     InstructionsSection_UnalignedHeaderSize = 20;
+static constexpr dart::compiler::target::word InstructionsTable_InstanceSize =
+    24;
 static constexpr dart::compiler::target::word Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word Integer_InstanceSize = 4;
 static constexpr dart::compiler::target::word KernelProgramInfo_InstanceSize =
@@ -558,7 +571,7 @@
     12;
 static constexpr dart::compiler::target::word UnlinkedCall_InstanceSize = 16;
 static constexpr dart::compiler::target::word UnwindError_InstanceSize = 12;
-static constexpr dart::compiler::target::word UserTag_InstanceSize = 12;
+static constexpr dart::compiler::target::word UserTag_InstanceSize = 16;
 static constexpr dart::compiler::target::word WeakProperty_InstanceSize = 16;
 static constexpr dart::compiler::target::word
     WeakSerializationReference_InstanceSize = 12;
@@ -586,10 +599,6 @@
     ExceptionHandlers_elements_start_offset = 24;
 static constexpr dart::compiler::target::word ExceptionHandlers_element_size =
     12;
-static constexpr dart::compiler::target::word
-    InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word InstructionsTable_element_size =
-    4;
 static constexpr dart::compiler::target::word ObjectPool_elements_start_offset =
     16;
 static constexpr dart::compiler::target::word ObjectPool_element_size = 8;
@@ -798,11 +807,11 @@
 static constexpr dart::compiler::target::word String_length_offset = 8;
 static constexpr dart::compiler::target::word SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    Thread_AllocateArray_entry_point_offset = 728;
+    Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word Thread_active_exception_offset =
-    1496;
-static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
     1504;
+static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
+    1512;
 static constexpr dart::compiler::target::word
     Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -828,22 +837,22 @@
 static constexpr dart::compiler::target::word
     Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word Thread_api_top_scope_offset =
-    1576;
+    1584;
 static constexpr dart::compiler::target::word
-    Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word Thread_bool_false_offset = 216;
 static constexpr dart::compiler::target::word Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_stub_offset = 264;
-static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1592;
+static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1624;
 static constexpr dart::compiler::target::word
     Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    Thread_double_truncate_round_supported_offset = 1584;
+    Thread_double_truncate_round_supported_offset = 1592;
 static constexpr dart::compiler::target::word Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word Thread_optimize_stub_offset = 440;
@@ -852,14 +861,14 @@
 static constexpr dart::compiler::target::word Thread_deoptimize_stub_offset =
     448;
 static constexpr dart::compiler::target::word Thread_double_abs_address_offset =
-    688;
+    696;
 static constexpr dart::compiler::target::word
-    Thread_double_negate_address_offset = 680;
+    Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word Thread_execution_state_offset =
-    1536;
+    1544;
 static constexpr dart::compiler::target::word
     Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -871,22 +880,22 @@
 static constexpr dart::compiler::target::word
     Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    Thread_float_absolute_address_offset = 712;
+    Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    Thread_float_negate_address_offset = 704;
+    Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word Thread_float_not_address_offset =
-    696;
+    704;
 static constexpr dart::compiler::target::word
-    Thread_float_zerow_address_offset = 720;
+    Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word Thread_global_object_pool_offset =
-    1512;
+    1520;
 static constexpr dart::compiler::target::word
     Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word Thread_exit_through_ffi_offset =
-    1568;
+    1576;
 static constexpr dart::compiler::target::word Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word Thread_isolate_group_offset =
-    1600;
+    1632;
 static constexpr dart::compiler::target::word Thread_field_table_values_offset =
     128;
 static constexpr dart::compiler::target::word
@@ -904,7 +913,7 @@
 static constexpr dart::compiler::target::word
     Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -927,16 +936,16 @@
     Thread_range_error_shared_without_fpu_regs_stub_offset = 336;
 static constexpr dart::compiler::target::word Thread_object_null_offset = 200;
 static constexpr dart::compiler::target::word
-    Thread_predefined_symbols_address_offset = 664;
-static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1520;
+    Thread_predefined_symbols_address_offset = 672;
+static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1528;
 static constexpr dart::compiler::target::word
-    Thread_saved_shadow_call_stack_offset = 1528;
+    Thread_saved_shadow_call_stack_offset = 1536;
 static constexpr dart::compiler::target::word Thread_safepoint_state_offset =
-    1544;
+    1552;
 static constexpr dart::compiler::target::word
     Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    Thread_slow_type_test_entry_point_offset = 632;
+    Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word Thread_stack_limit_offset = 56;
 static constexpr dart::compiler::target::word Thread_saved_stack_limit_offset =
     112;
@@ -969,9 +978,23 @@
     64;
 static constexpr dart::compiler::target::word Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word Thread_callback_code_offset =
-    1552;
+    1560;
 static constexpr dart::compiler::target::word
-    Thread_callback_stack_return_offset = 1560;
+    Thread_callback_stack_return_offset = 1568;
+static constexpr dart::compiler::target::word Thread_random_offset = 1600;
+static constexpr dart::compiler::target::word
+    Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word Thread_tsan_utils_offset = 1608;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_function_offset =
+    0;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_buffer_offset =
+    8;
+static constexpr dart::compiler::target::word TsanUtils_exception_pc_offset =
+    16;
+static constexpr dart::compiler::target::word TsanUtils_exception_sp_offset =
+    24;
+static constexpr dart::compiler::target::word TsanUtils_exception_fp_offset =
+    32;
 static constexpr dart::compiler::target::word TimelineStream_enabled_offset =
     16;
 static constexpr dart::compiler::target::word TwoByteString_data_offset = 16;
@@ -1032,8 +1055,8 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, -1,   -1,   1440, 1448,
-        1456, 1464, 1472, -1,   1480, 1488, -1,   -1};
+        1416, 1424, 1432, 1440, -1,   -1,   1448, 1456,
+        1464, 1472, 1480, -1,   1488, 1496, -1,   -1};
 static constexpr dart::compiler::target::word AbstractType_InstanceSize = 24;
 static constexpr dart::compiler::target::word ApiError_InstanceSize = 16;
 static constexpr dart::compiler::target::word Array_header_size = 24;
@@ -1043,8 +1066,10 @@
 static constexpr dart::compiler::target::word Closure_InstanceSize = 56;
 static constexpr dart::compiler::target::word ClosureData_InstanceSize = 40;
 static constexpr dart::compiler::target::word CodeSourceMap_HeaderSize = 16;
-static constexpr dart::compiler::target::word CompressedStackMaps_HeaderSize =
-    16;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word Context_header_size = 24;
 static constexpr dart::compiler::target::word Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word DynamicLibrary_InstanceSize = 16;
@@ -1070,6 +1095,8 @@
     16;
 static constexpr dart::compiler::target::word
     InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word InstructionsTable_InstanceSize =
+    48;
 static constexpr dart::compiler::target::word Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word KernelProgramInfo_InstanceSize =
@@ -1116,7 +1143,7 @@
     24;
 static constexpr dart::compiler::target::word UnlinkedCall_InstanceSize = 32;
 static constexpr dart::compiler::target::word UnwindError_InstanceSize = 24;
-static constexpr dart::compiler::target::word UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word WeakProperty_InstanceSize = 32;
 static constexpr dart::compiler::target::word
     WeakSerializationReference_InstanceSize = 24;
@@ -1144,10 +1171,6 @@
     ExceptionHandlers_elements_start_offset = 12;
 static constexpr dart::compiler::target::word ExceptionHandlers_element_size =
     12;
-static constexpr dart::compiler::target::word
-    InstructionsTable_elements_start_offset = 20;
-static constexpr dart::compiler::target::word InstructionsTable_element_size =
-    4;
 static constexpr dart::compiler::target::word ObjectPool_elements_start_offset =
     8;
 static constexpr dart::compiler::target::word ObjectPool_element_size = 4;
@@ -1351,11 +1374,11 @@
 static constexpr dart::compiler::target::word String_length_offset = 4;
 static constexpr dart::compiler::target::word SubtypeTestCache_cache_offset = 4;
 static constexpr dart::compiler::target::word
-    Thread_AllocateArray_entry_point_offset = 376;
+    Thread_AllocateArray_entry_point_offset = 380;
 static constexpr dart::compiler::target::word Thread_active_exception_offset =
-    716;
-static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
     720;
+static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
+    724;
 static constexpr dart::compiler::target::word
     Thread_array_write_barrier_code_offset = 128;
 static constexpr dart::compiler::target::word
@@ -1380,22 +1403,22 @@
     Thread_allocate_object_slow_entry_point_offset = 296;
 static constexpr dart::compiler::target::word
     Thread_allocate_object_slow_stub_offset = 204;
-static constexpr dart::compiler::target::word Thread_api_top_scope_offset = 756;
+static constexpr dart::compiler::target::word Thread_api_top_scope_offset = 760;
 static constexpr dart::compiler::target::word
-    Thread_auto_scope_native_wrapper_entry_point_offset = 340;
+    Thread_auto_scope_native_wrapper_entry_point_offset = 344;
 static constexpr dart::compiler::target::word Thread_bool_false_offset = 120;
 static constexpr dart::compiler::target::word Thread_bool_true_offset = 116;
 static constexpr dart::compiler::target::word
-    Thread_bootstrap_native_wrapper_entry_point_offset = 332;
+    Thread_bootstrap_native_wrapper_entry_point_offset = 336;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_entry_point_offset = 276;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_stub_offset = 144;
-static constexpr dart::compiler::target::word Thread_dart_stream_offset = 768;
+static constexpr dart::compiler::target::word Thread_dart_stream_offset = 784;
 static constexpr dart::compiler::target::word
     Thread_dispatch_table_array_offset = 44;
 static constexpr dart::compiler::target::word
-    Thread_double_truncate_round_supported_offset = 760;
+    Thread_double_truncate_round_supported_offset = 764;
 static constexpr dart::compiler::target::word Thread_optimize_entry_offset =
     316;
 static constexpr dart::compiler::target::word Thread_optimize_stub_offset = 232;
@@ -1404,14 +1427,14 @@
 static constexpr dart::compiler::target::word Thread_deoptimize_stub_offset =
     236;
 static constexpr dart::compiler::target::word Thread_double_abs_address_offset =
-    356;
+    360;
 static constexpr dart::compiler::target::word
-    Thread_double_negate_address_offset = 352;
+    Thread_double_negate_address_offset = 356;
 static constexpr dart::compiler::target::word Thread_end_offset = 52;
 static constexpr dart::compiler::target::word
     Thread_enter_safepoint_stub_offset = 256;
 static constexpr dart::compiler::target::word Thread_execution_state_offset =
-    736;
+    740;
 static constexpr dart::compiler::target::word
     Thread_exit_safepoint_stub_offset = 260;
 static constexpr dart::compiler::target::word
@@ -1423,21 +1446,21 @@
 static constexpr dart::compiler::target::word
     Thread_fix_callers_target_code_offset = 132;
 static constexpr dart::compiler::target::word
-    Thread_float_absolute_address_offset = 368;
+    Thread_float_absolute_address_offset = 372;
 static constexpr dart::compiler::target::word
-    Thread_float_negate_address_offset = 364;
+    Thread_float_negate_address_offset = 368;
 static constexpr dart::compiler::target::word Thread_float_not_address_offset =
-    360;
+    364;
 static constexpr dart::compiler::target::word
-    Thread_float_zerow_address_offset = 372;
+    Thread_float_zerow_address_offset = 376;
 static constexpr dart::compiler::target::word Thread_global_object_pool_offset =
-    724;
+    728;
 static constexpr dart::compiler::target::word
     Thread_invoke_dart_code_stub_offset = 140;
 static constexpr dart::compiler::target::word Thread_exit_through_ffi_offset =
-    752;
+    756;
 static constexpr dart::compiler::target::word Thread_isolate_offset = 40;
-static constexpr dart::compiler::target::word Thread_isolate_group_offset = 772;
+static constexpr dart::compiler::target::word Thread_isolate_group_offset = 788;
 static constexpr dart::compiler::target::word Thread_field_table_values_offset =
     64;
 static constexpr dart::compiler::target::word
@@ -1455,7 +1478,7 @@
 static constexpr dart::compiler::target::word
     Thread_switchable_call_miss_stub_offset = 216;
 static constexpr dart::compiler::target::word
-    Thread_no_scope_native_wrapper_entry_point_offset = 336;
+    Thread_no_scope_native_wrapper_entry_point_offset = 340;
 static constexpr dart::compiler::target::word
     Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 152;
 static constexpr dart::compiler::target::word
@@ -1478,16 +1501,16 @@
     Thread_range_error_shared_without_fpu_regs_stub_offset = 180;
 static constexpr dart::compiler::target::word Thread_object_null_offset = 112;
 static constexpr dart::compiler::target::word
-    Thread_predefined_symbols_address_offset = 344;
-static constexpr dart::compiler::target::word Thread_resume_pc_offset = 728;
+    Thread_predefined_symbols_address_offset = 348;
+static constexpr dart::compiler::target::word Thread_resume_pc_offset = 732;
 static constexpr dart::compiler::target::word
-    Thread_saved_shadow_call_stack_offset = 732;
+    Thread_saved_shadow_call_stack_offset = 736;
 static constexpr dart::compiler::target::word Thread_safepoint_state_offset =
-    740;
+    744;
 static constexpr dart::compiler::target::word
     Thread_slow_type_test_stub_offset = 248;
 static constexpr dart::compiler::target::word
-    Thread_slow_type_test_entry_point_offset = 328;
+    Thread_slow_type_test_entry_point_offset = 332;
 static constexpr dart::compiler::target::word Thread_stack_limit_offset = 28;
 static constexpr dart::compiler::target::word Thread_saved_stack_limit_offset =
     56;
@@ -1519,9 +1542,22 @@
 static constexpr dart::compiler::target::word Thread_write_barrier_mask_offset =
     32;
 static constexpr dart::compiler::target::word Thread_heap_base_offset = 36;
-static constexpr dart::compiler::target::word Thread_callback_code_offset = 744;
+static constexpr dart::compiler::target::word Thread_callback_code_offset = 748;
 static constexpr dart::compiler::target::word
-    Thread_callback_stack_return_offset = 748;
+    Thread_callback_stack_return_offset = 752;
+static constexpr dart::compiler::target::word Thread_random_offset = 768;
+static constexpr dart::compiler::target::word
+    Thread_jump_to_frame_entry_point_offset = 328;
+static constexpr dart::compiler::target::word Thread_tsan_utils_offset = 776;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_function_offset =
+    0;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_buffer_offset =
+    4;
+static constexpr dart::compiler::target::word TsanUtils_exception_pc_offset = 8;
+static constexpr dart::compiler::target::word TsanUtils_exception_sp_offset =
+    12;
+static constexpr dart::compiler::target::word TsanUtils_exception_fp_offset =
+    16;
 static constexpr dart::compiler::target::word TimelineStream_enabled_offset = 8;
 static constexpr dart::compiler::target::word TwoByteString_data_offset = 12;
 static constexpr dart::compiler::target::word Type_arguments_offset = 12;
@@ -1588,8 +1624,10 @@
 static constexpr dart::compiler::target::word Closure_InstanceSize = 28;
 static constexpr dart::compiler::target::word ClosureData_InstanceSize = 20;
 static constexpr dart::compiler::target::word CodeSourceMap_HeaderSize = 8;
-static constexpr dart::compiler::target::word CompressedStackMaps_HeaderSize =
-    8;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_ObjectHeaderSize = 4;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word Context_header_size = 12;
 static constexpr dart::compiler::target::word Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word DynamicLibrary_InstanceSize = 8;
@@ -1615,6 +1653,8 @@
     8;
 static constexpr dart::compiler::target::word
     InstructionsSection_UnalignedHeaderSize = 20;
+static constexpr dart::compiler::target::word InstructionsTable_InstanceSize =
+    24;
 static constexpr dart::compiler::target::word Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word Integer_InstanceSize = 4;
 static constexpr dart::compiler::target::word KernelProgramInfo_InstanceSize =
@@ -1660,7 +1700,7 @@
     12;
 static constexpr dart::compiler::target::word UnlinkedCall_InstanceSize = 16;
 static constexpr dart::compiler::target::word UnwindError_InstanceSize = 12;
-static constexpr dart::compiler::target::word UserTag_InstanceSize = 12;
+static constexpr dart::compiler::target::word UserTag_InstanceSize = 16;
 static constexpr dart::compiler::target::word WeakProperty_InstanceSize = 16;
 static constexpr dart::compiler::target::word
     WeakSerializationReference_InstanceSize = 12;
@@ -1688,10 +1728,6 @@
     ExceptionHandlers_elements_start_offset = 24;
 static constexpr dart::compiler::target::word ExceptionHandlers_element_size =
     12;
-static constexpr dart::compiler::target::word
-    InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word InstructionsTable_element_size =
-    4;
 static constexpr dart::compiler::target::word ObjectPool_elements_start_offset =
     16;
 static constexpr dart::compiler::target::word ObjectPool_element_size = 8;
@@ -1900,11 +1936,11 @@
 static constexpr dart::compiler::target::word String_length_offset = 8;
 static constexpr dart::compiler::target::word SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    Thread_AllocateArray_entry_point_offset = 728;
+    Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word Thread_active_exception_offset =
-    1560;
-static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
     1568;
+static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
+    1576;
 static constexpr dart::compiler::target::word
     Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -1930,22 +1966,22 @@
 static constexpr dart::compiler::target::word
     Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word Thread_api_top_scope_offset =
-    1640;
+    1648;
 static constexpr dart::compiler::target::word
-    Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word Thread_bool_false_offset = 216;
 static constexpr dart::compiler::target::word Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_stub_offset = 264;
-static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1656;
+static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1688;
 static constexpr dart::compiler::target::word
     Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    Thread_double_truncate_round_supported_offset = 1648;
+    Thread_double_truncate_round_supported_offset = 1656;
 static constexpr dart::compiler::target::word Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word Thread_optimize_stub_offset = 440;
@@ -1954,14 +1990,14 @@
 static constexpr dart::compiler::target::word Thread_deoptimize_stub_offset =
     448;
 static constexpr dart::compiler::target::word Thread_double_abs_address_offset =
-    688;
+    696;
 static constexpr dart::compiler::target::word
-    Thread_double_negate_address_offset = 680;
+    Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word Thread_execution_state_offset =
-    1600;
+    1608;
 static constexpr dart::compiler::target::word
     Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -1973,22 +2009,22 @@
 static constexpr dart::compiler::target::word
     Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    Thread_float_absolute_address_offset = 712;
+    Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    Thread_float_negate_address_offset = 704;
+    Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word Thread_float_not_address_offset =
-    696;
+    704;
 static constexpr dart::compiler::target::word
-    Thread_float_zerow_address_offset = 720;
+    Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word Thread_global_object_pool_offset =
-    1576;
+    1584;
 static constexpr dart::compiler::target::word
     Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word Thread_exit_through_ffi_offset =
-    1632;
+    1640;
 static constexpr dart::compiler::target::word Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word Thread_isolate_group_offset =
-    1664;
+    1696;
 static constexpr dart::compiler::target::word Thread_field_table_values_offset =
     128;
 static constexpr dart::compiler::target::word
@@ -2006,7 +2042,7 @@
 static constexpr dart::compiler::target::word
     Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -2029,16 +2065,16 @@
     Thread_range_error_shared_without_fpu_regs_stub_offset = 336;
 static constexpr dart::compiler::target::word Thread_object_null_offset = 200;
 static constexpr dart::compiler::target::word
-    Thread_predefined_symbols_address_offset = 664;
-static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1584;
+    Thread_predefined_symbols_address_offset = 672;
+static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1592;
 static constexpr dart::compiler::target::word
-    Thread_saved_shadow_call_stack_offset = 1592;
+    Thread_saved_shadow_call_stack_offset = 1600;
 static constexpr dart::compiler::target::word Thread_safepoint_state_offset =
-    1608;
+    1616;
 static constexpr dart::compiler::target::word
     Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    Thread_slow_type_test_entry_point_offset = 632;
+    Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word Thread_stack_limit_offset = 56;
 static constexpr dart::compiler::target::word Thread_saved_stack_limit_offset =
     112;
@@ -2071,9 +2107,23 @@
     64;
 static constexpr dart::compiler::target::word Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word Thread_callback_code_offset =
-    1616;
+    1624;
 static constexpr dart::compiler::target::word
-    Thread_callback_stack_return_offset = 1624;
+    Thread_callback_stack_return_offset = 1632;
+static constexpr dart::compiler::target::word Thread_random_offset = 1664;
+static constexpr dart::compiler::target::word
+    Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word Thread_tsan_utils_offset = 1672;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_function_offset =
+    0;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_buffer_offset =
+    8;
+static constexpr dart::compiler::target::word TsanUtils_exception_pc_offset =
+    16;
+static constexpr dart::compiler::target::word TsanUtils_exception_sp_offset =
+    24;
+static constexpr dart::compiler::target::word TsanUtils_exception_fp_offset =
+    32;
 static constexpr dart::compiler::target::word TimelineStream_enabled_offset =
     16;
 static constexpr dart::compiler::target::word TwoByteString_data_offset = 16;
@@ -2134,9 +2184,9 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488,
-        1496, 1504, 1512, 1520, -1,   -1,   -1,   -1,   1528, 1536, -1,
-        -1,   1544, 1552, 1560, -1,   -1,   -1,   -1,   -1,   -1};
+        1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488, 1496,
+        1504, 1512, 1520, 1528, -1,   -1,   -1,   -1,   1536, 1544, -1,
+        -1,   1552, 1560, 1568, -1,   -1,   -1,   -1,   -1,   -1};
 static constexpr dart::compiler::target::word AbstractType_InstanceSize = 24;
 static constexpr dart::compiler::target::word ApiError_InstanceSize = 16;
 static constexpr dart::compiler::target::word Array_header_size = 24;
@@ -2146,8 +2196,10 @@
 static constexpr dart::compiler::target::word Closure_InstanceSize = 56;
 static constexpr dart::compiler::target::word ClosureData_InstanceSize = 40;
 static constexpr dart::compiler::target::word CodeSourceMap_HeaderSize = 16;
-static constexpr dart::compiler::target::word CompressedStackMaps_HeaderSize =
-    16;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word Context_header_size = 24;
 static constexpr dart::compiler::target::word Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word DynamicLibrary_InstanceSize = 16;
@@ -2173,6 +2225,8 @@
     16;
 static constexpr dart::compiler::target::word
     InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word InstructionsTable_InstanceSize =
+    48;
 static constexpr dart::compiler::target::word Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word KernelProgramInfo_InstanceSize =
@@ -2219,7 +2273,7 @@
     24;
 static constexpr dart::compiler::target::word UnlinkedCall_InstanceSize = 32;
 static constexpr dart::compiler::target::word UnwindError_InstanceSize = 24;
-static constexpr dart::compiler::target::word UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word WeakProperty_InstanceSize = 32;
 static constexpr dart::compiler::target::word
     WeakSerializationReference_InstanceSize = 24;
@@ -2247,10 +2301,6 @@
     ExceptionHandlers_elements_start_offset = 16;
 static constexpr dart::compiler::target::word ExceptionHandlers_element_size =
     12;
-static constexpr dart::compiler::target::word
-    InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word InstructionsTable_element_size =
-    4;
 static constexpr dart::compiler::target::word ObjectPool_elements_start_offset =
     16;
 static constexpr dart::compiler::target::word ObjectPool_element_size = 8;
@@ -2456,11 +2506,11 @@
 static constexpr dart::compiler::target::word String_length_offset = 8;
 static constexpr dart::compiler::target::word SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    Thread_AllocateArray_entry_point_offset = 728;
+    Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word Thread_active_exception_offset =
-    1496;
-static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
     1504;
+static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
+    1512;
 static constexpr dart::compiler::target::word
     Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -2486,22 +2536,22 @@
 static constexpr dart::compiler::target::word
     Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word Thread_api_top_scope_offset =
-    1576;
+    1584;
 static constexpr dart::compiler::target::word
-    Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word Thread_bool_false_offset = 216;
 static constexpr dart::compiler::target::word Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_stub_offset = 264;
-static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1592;
+static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1624;
 static constexpr dart::compiler::target::word
     Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    Thread_double_truncate_round_supported_offset = 1584;
+    Thread_double_truncate_round_supported_offset = 1592;
 static constexpr dart::compiler::target::word Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word Thread_optimize_stub_offset = 440;
@@ -2510,14 +2560,14 @@
 static constexpr dart::compiler::target::word Thread_deoptimize_stub_offset =
     448;
 static constexpr dart::compiler::target::word Thread_double_abs_address_offset =
-    688;
+    696;
 static constexpr dart::compiler::target::word
-    Thread_double_negate_address_offset = 680;
+    Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word Thread_execution_state_offset =
-    1536;
+    1544;
 static constexpr dart::compiler::target::word
     Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -2529,22 +2579,22 @@
 static constexpr dart::compiler::target::word
     Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    Thread_float_absolute_address_offset = 712;
+    Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    Thread_float_negate_address_offset = 704;
+    Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word Thread_float_not_address_offset =
-    696;
+    704;
 static constexpr dart::compiler::target::word
-    Thread_float_zerow_address_offset = 720;
+    Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word Thread_global_object_pool_offset =
-    1512;
+    1520;
 static constexpr dart::compiler::target::word
     Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word Thread_exit_through_ffi_offset =
-    1568;
+    1576;
 static constexpr dart::compiler::target::word Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word Thread_isolate_group_offset =
-    1600;
+    1632;
 static constexpr dart::compiler::target::word Thread_field_table_values_offset =
     128;
 static constexpr dart::compiler::target::word
@@ -2562,7 +2612,7 @@
 static constexpr dart::compiler::target::word
     Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -2585,16 +2635,16 @@
     Thread_range_error_shared_without_fpu_regs_stub_offset = 336;
 static constexpr dart::compiler::target::word Thread_object_null_offset = 200;
 static constexpr dart::compiler::target::word
-    Thread_predefined_symbols_address_offset = 664;
-static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1520;
+    Thread_predefined_symbols_address_offset = 672;
+static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1528;
 static constexpr dart::compiler::target::word
-    Thread_saved_shadow_call_stack_offset = 1528;
+    Thread_saved_shadow_call_stack_offset = 1536;
 static constexpr dart::compiler::target::word Thread_safepoint_state_offset =
-    1544;
+    1552;
 static constexpr dart::compiler::target::word
     Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    Thread_slow_type_test_entry_point_offset = 632;
+    Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word Thread_stack_limit_offset = 56;
 static constexpr dart::compiler::target::word Thread_saved_stack_limit_offset =
     112;
@@ -2627,9 +2677,23 @@
     64;
 static constexpr dart::compiler::target::word Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word Thread_callback_code_offset =
-    1552;
+    1560;
 static constexpr dart::compiler::target::word
-    Thread_callback_stack_return_offset = 1560;
+    Thread_callback_stack_return_offset = 1568;
+static constexpr dart::compiler::target::word Thread_random_offset = 1600;
+static constexpr dart::compiler::target::word
+    Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word Thread_tsan_utils_offset = 1608;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_function_offset =
+    0;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_buffer_offset =
+    8;
+static constexpr dart::compiler::target::word TsanUtils_exception_pc_offset =
+    16;
+static constexpr dart::compiler::target::word TsanUtils_exception_sp_offset =
+    24;
+static constexpr dart::compiler::target::word TsanUtils_exception_fp_offset =
+    32;
 static constexpr dart::compiler::target::word TimelineStream_enabled_offset =
     16;
 static constexpr dart::compiler::target::word TwoByteString_data_offset = 16;
@@ -2690,8 +2754,8 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, -1,   -1,   1440, 1448,
-        1456, 1464, 1472, -1,   1480, 1488, -1,   -1};
+        1416, 1424, 1432, 1440, -1,   -1,   1448, 1456,
+        1464, 1472, 1480, -1,   1488, 1496, -1,   -1};
 static constexpr dart::compiler::target::word AbstractType_InstanceSize = 24;
 static constexpr dart::compiler::target::word ApiError_InstanceSize = 16;
 static constexpr dart::compiler::target::word Array_header_size = 16;
@@ -2701,8 +2765,10 @@
 static constexpr dart::compiler::target::word Closure_InstanceSize = 32;
 static constexpr dart::compiler::target::word ClosureData_InstanceSize = 24;
 static constexpr dart::compiler::target::word CodeSourceMap_HeaderSize = 16;
-static constexpr dart::compiler::target::word CompressedStackMaps_HeaderSize =
-    16;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word Context_header_size = 16;
 static constexpr dart::compiler::target::word Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word DynamicLibrary_InstanceSize = 16;
@@ -2728,6 +2794,8 @@
     16;
 static constexpr dart::compiler::target::word
     InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word InstructionsTable_InstanceSize =
+    48;
 static constexpr dart::compiler::target::word Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word KernelProgramInfo_InstanceSize =
@@ -2774,7 +2842,7 @@
     16;
 static constexpr dart::compiler::target::word UnlinkedCall_InstanceSize = 32;
 static constexpr dart::compiler::target::word UnwindError_InstanceSize = 16;
-static constexpr dart::compiler::target::word UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word WeakProperty_InstanceSize = 24;
 static constexpr dart::compiler::target::word
     WeakSerializationReference_InstanceSize = 16;
@@ -2802,10 +2870,6 @@
     ExceptionHandlers_elements_start_offset = 16;
 static constexpr dart::compiler::target::word ExceptionHandlers_element_size =
     12;
-static constexpr dart::compiler::target::word
-    InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word InstructionsTable_element_size =
-    4;
 static constexpr dart::compiler::target::word ObjectPool_elements_start_offset =
     16;
 static constexpr dart::compiler::target::word ObjectPool_element_size = 8;
@@ -3011,11 +3075,11 @@
 static constexpr dart::compiler::target::word String_length_offset = 8;
 static constexpr dart::compiler::target::word SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    Thread_AllocateArray_entry_point_offset = 728;
+    Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word Thread_active_exception_offset =
-    1560;
-static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
     1568;
+static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
+    1576;
 static constexpr dart::compiler::target::word
     Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -3041,22 +3105,22 @@
 static constexpr dart::compiler::target::word
     Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word Thread_api_top_scope_offset =
-    1640;
+    1648;
 static constexpr dart::compiler::target::word
-    Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word Thread_bool_false_offset = 216;
 static constexpr dart::compiler::target::word Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_stub_offset = 264;
-static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1656;
+static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1688;
 static constexpr dart::compiler::target::word
     Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    Thread_double_truncate_round_supported_offset = 1648;
+    Thread_double_truncate_round_supported_offset = 1656;
 static constexpr dart::compiler::target::word Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word Thread_optimize_stub_offset = 440;
@@ -3065,14 +3129,14 @@
 static constexpr dart::compiler::target::word Thread_deoptimize_stub_offset =
     448;
 static constexpr dart::compiler::target::word Thread_double_abs_address_offset =
-    688;
+    696;
 static constexpr dart::compiler::target::word
-    Thread_double_negate_address_offset = 680;
+    Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word Thread_execution_state_offset =
-    1600;
+    1608;
 static constexpr dart::compiler::target::word
     Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -3084,22 +3148,22 @@
 static constexpr dart::compiler::target::word
     Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    Thread_float_absolute_address_offset = 712;
+    Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    Thread_float_negate_address_offset = 704;
+    Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word Thread_float_not_address_offset =
-    696;
+    704;
 static constexpr dart::compiler::target::word
-    Thread_float_zerow_address_offset = 720;
+    Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word Thread_global_object_pool_offset =
-    1576;
+    1584;
 static constexpr dart::compiler::target::word
     Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word Thread_exit_through_ffi_offset =
-    1632;
+    1640;
 static constexpr dart::compiler::target::word Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word Thread_isolate_group_offset =
-    1664;
+    1696;
 static constexpr dart::compiler::target::word Thread_field_table_values_offset =
     128;
 static constexpr dart::compiler::target::word
@@ -3117,7 +3181,7 @@
 static constexpr dart::compiler::target::word
     Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -3140,16 +3204,16 @@
     Thread_range_error_shared_without_fpu_regs_stub_offset = 336;
 static constexpr dart::compiler::target::word Thread_object_null_offset = 200;
 static constexpr dart::compiler::target::word
-    Thread_predefined_symbols_address_offset = 664;
-static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1584;
+    Thread_predefined_symbols_address_offset = 672;
+static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1592;
 static constexpr dart::compiler::target::word
-    Thread_saved_shadow_call_stack_offset = 1592;
+    Thread_saved_shadow_call_stack_offset = 1600;
 static constexpr dart::compiler::target::word Thread_safepoint_state_offset =
-    1608;
+    1616;
 static constexpr dart::compiler::target::word
     Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    Thread_slow_type_test_entry_point_offset = 632;
+    Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word Thread_stack_limit_offset = 56;
 static constexpr dart::compiler::target::word Thread_saved_stack_limit_offset =
     112;
@@ -3182,9 +3246,23 @@
     64;
 static constexpr dart::compiler::target::word Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word Thread_callback_code_offset =
-    1616;
+    1624;
 static constexpr dart::compiler::target::word
-    Thread_callback_stack_return_offset = 1624;
+    Thread_callback_stack_return_offset = 1632;
+static constexpr dart::compiler::target::word Thread_random_offset = 1664;
+static constexpr dart::compiler::target::word
+    Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word Thread_tsan_utils_offset = 1672;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_function_offset =
+    0;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_buffer_offset =
+    8;
+static constexpr dart::compiler::target::word TsanUtils_exception_pc_offset =
+    16;
+static constexpr dart::compiler::target::word TsanUtils_exception_sp_offset =
+    24;
+static constexpr dart::compiler::target::word TsanUtils_exception_fp_offset =
+    32;
 static constexpr dart::compiler::target::word TimelineStream_enabled_offset =
     16;
 static constexpr dart::compiler::target::word TwoByteString_data_offset = 16;
@@ -3245,9 +3323,9 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488,
-        1496, 1504, 1512, 1520, -1,   -1,   -1,   -1,   1528, 1536, -1,
-        -1,   1544, 1552, 1560, -1,   -1,   -1,   -1,   -1,   -1};
+        1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488, 1496,
+        1504, 1512, 1520, 1528, -1,   -1,   -1,   -1,   1536, 1544, -1,
+        -1,   1552, 1560, 1568, -1,   -1,   -1,   -1,   -1,   -1};
 static constexpr dart::compiler::target::word AbstractType_InstanceSize = 24;
 static constexpr dart::compiler::target::word ApiError_InstanceSize = 16;
 static constexpr dart::compiler::target::word Array_header_size = 16;
@@ -3257,8 +3335,10 @@
 static constexpr dart::compiler::target::word Closure_InstanceSize = 32;
 static constexpr dart::compiler::target::word ClosureData_InstanceSize = 24;
 static constexpr dart::compiler::target::word CodeSourceMap_HeaderSize = 16;
-static constexpr dart::compiler::target::word CompressedStackMaps_HeaderSize =
-    16;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word Context_header_size = 16;
 static constexpr dart::compiler::target::word Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word DynamicLibrary_InstanceSize = 16;
@@ -3284,6 +3364,8 @@
     16;
 static constexpr dart::compiler::target::word
     InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word InstructionsTable_InstanceSize =
+    48;
 static constexpr dart::compiler::target::word Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word KernelProgramInfo_InstanceSize =
@@ -3330,7 +3412,7 @@
     16;
 static constexpr dart::compiler::target::word UnlinkedCall_InstanceSize = 32;
 static constexpr dart::compiler::target::word UnwindError_InstanceSize = 16;
-static constexpr dart::compiler::target::word UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word WeakProperty_InstanceSize = 24;
 static constexpr dart::compiler::target::word
     WeakSerializationReference_InstanceSize = 16;
@@ -3357,10 +3439,6 @@
     ExceptionHandlers_elements_start_offset = 12;
 static constexpr dart::compiler::target::word ExceptionHandlers_element_size =
     12;
-static constexpr dart::compiler::target::word
-    InstructionsTable_elements_start_offset = 20;
-static constexpr dart::compiler::target::word InstructionsTable_element_size =
-    4;
 static constexpr dart::compiler::target::word ObjectPool_elements_start_offset =
     8;
 static constexpr dart::compiler::target::word ObjectPool_element_size = 4;
@@ -3561,11 +3639,11 @@
 static constexpr dart::compiler::target::word String_length_offset = 4;
 static constexpr dart::compiler::target::word SubtypeTestCache_cache_offset = 4;
 static constexpr dart::compiler::target::word
-    Thread_AllocateArray_entry_point_offset = 376;
+    Thread_AllocateArray_entry_point_offset = 380;
 static constexpr dart::compiler::target::word Thread_active_exception_offset =
-    748;
-static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
     752;
+static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
+    756;
 static constexpr dart::compiler::target::word
     Thread_array_write_barrier_code_offset = 128;
 static constexpr dart::compiler::target::word
@@ -3590,22 +3668,22 @@
     Thread_allocate_object_slow_entry_point_offset = 296;
 static constexpr dart::compiler::target::word
     Thread_allocate_object_slow_stub_offset = 204;
-static constexpr dart::compiler::target::word Thread_api_top_scope_offset = 788;
+static constexpr dart::compiler::target::word Thread_api_top_scope_offset = 792;
 static constexpr dart::compiler::target::word
-    Thread_auto_scope_native_wrapper_entry_point_offset = 340;
+    Thread_auto_scope_native_wrapper_entry_point_offset = 344;
 static constexpr dart::compiler::target::word Thread_bool_false_offset = 120;
 static constexpr dart::compiler::target::word Thread_bool_true_offset = 116;
 static constexpr dart::compiler::target::word
-    Thread_bootstrap_native_wrapper_entry_point_offset = 332;
+    Thread_bootstrap_native_wrapper_entry_point_offset = 336;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_entry_point_offset = 276;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_stub_offset = 144;
-static constexpr dart::compiler::target::word Thread_dart_stream_offset = 800;
+static constexpr dart::compiler::target::word Thread_dart_stream_offset = 816;
 static constexpr dart::compiler::target::word
     Thread_dispatch_table_array_offset = 44;
 static constexpr dart::compiler::target::word
-    Thread_double_truncate_round_supported_offset = 792;
+    Thread_double_truncate_round_supported_offset = 796;
 static constexpr dart::compiler::target::word Thread_optimize_entry_offset =
     316;
 static constexpr dart::compiler::target::word Thread_optimize_stub_offset = 232;
@@ -3614,14 +3692,14 @@
 static constexpr dart::compiler::target::word Thread_deoptimize_stub_offset =
     236;
 static constexpr dart::compiler::target::word Thread_double_abs_address_offset =
-    356;
+    360;
 static constexpr dart::compiler::target::word
-    Thread_double_negate_address_offset = 352;
+    Thread_double_negate_address_offset = 356;
 static constexpr dart::compiler::target::word Thread_end_offset = 52;
 static constexpr dart::compiler::target::word
     Thread_enter_safepoint_stub_offset = 256;
 static constexpr dart::compiler::target::word Thread_execution_state_offset =
-    768;
+    772;
 static constexpr dart::compiler::target::word
     Thread_exit_safepoint_stub_offset = 260;
 static constexpr dart::compiler::target::word
@@ -3633,21 +3711,21 @@
 static constexpr dart::compiler::target::word
     Thread_fix_callers_target_code_offset = 132;
 static constexpr dart::compiler::target::word
-    Thread_float_absolute_address_offset = 368;
+    Thread_float_absolute_address_offset = 372;
 static constexpr dart::compiler::target::word
-    Thread_float_negate_address_offset = 364;
+    Thread_float_negate_address_offset = 368;
 static constexpr dart::compiler::target::word Thread_float_not_address_offset =
-    360;
+    364;
 static constexpr dart::compiler::target::word
-    Thread_float_zerow_address_offset = 372;
+    Thread_float_zerow_address_offset = 376;
 static constexpr dart::compiler::target::word Thread_global_object_pool_offset =
-    756;
+    760;
 static constexpr dart::compiler::target::word
     Thread_invoke_dart_code_stub_offset = 140;
 static constexpr dart::compiler::target::word Thread_exit_through_ffi_offset =
-    784;
+    788;
 static constexpr dart::compiler::target::word Thread_isolate_offset = 40;
-static constexpr dart::compiler::target::word Thread_isolate_group_offset = 804;
+static constexpr dart::compiler::target::word Thread_isolate_group_offset = 820;
 static constexpr dart::compiler::target::word Thread_field_table_values_offset =
     64;
 static constexpr dart::compiler::target::word
@@ -3665,7 +3743,7 @@
 static constexpr dart::compiler::target::word
     Thread_switchable_call_miss_stub_offset = 216;
 static constexpr dart::compiler::target::word
-    Thread_no_scope_native_wrapper_entry_point_offset = 336;
+    Thread_no_scope_native_wrapper_entry_point_offset = 340;
 static constexpr dart::compiler::target::word
     Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 152;
 static constexpr dart::compiler::target::word
@@ -3688,16 +3766,16 @@
     Thread_range_error_shared_without_fpu_regs_stub_offset = 180;
 static constexpr dart::compiler::target::word Thread_object_null_offset = 112;
 static constexpr dart::compiler::target::word
-    Thread_predefined_symbols_address_offset = 344;
-static constexpr dart::compiler::target::word Thread_resume_pc_offset = 760;
+    Thread_predefined_symbols_address_offset = 348;
+static constexpr dart::compiler::target::word Thread_resume_pc_offset = 764;
 static constexpr dart::compiler::target::word
-    Thread_saved_shadow_call_stack_offset = 764;
+    Thread_saved_shadow_call_stack_offset = 768;
 static constexpr dart::compiler::target::word Thread_safepoint_state_offset =
-    772;
+    776;
 static constexpr dart::compiler::target::word
     Thread_slow_type_test_stub_offset = 248;
 static constexpr dart::compiler::target::word
-    Thread_slow_type_test_entry_point_offset = 328;
+    Thread_slow_type_test_entry_point_offset = 332;
 static constexpr dart::compiler::target::word Thread_stack_limit_offset = 28;
 static constexpr dart::compiler::target::word Thread_saved_stack_limit_offset =
     56;
@@ -3729,9 +3807,22 @@
 static constexpr dart::compiler::target::word Thread_write_barrier_mask_offset =
     32;
 static constexpr dart::compiler::target::word Thread_heap_base_offset = 36;
-static constexpr dart::compiler::target::word Thread_callback_code_offset = 776;
+static constexpr dart::compiler::target::word Thread_callback_code_offset = 780;
 static constexpr dart::compiler::target::word
-    Thread_callback_stack_return_offset = 780;
+    Thread_callback_stack_return_offset = 784;
+static constexpr dart::compiler::target::word Thread_random_offset = 800;
+static constexpr dart::compiler::target::word
+    Thread_jump_to_frame_entry_point_offset = 328;
+static constexpr dart::compiler::target::word Thread_tsan_utils_offset = 808;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_function_offset =
+    0;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_buffer_offset =
+    4;
+static constexpr dart::compiler::target::word TsanUtils_exception_pc_offset = 8;
+static constexpr dart::compiler::target::word TsanUtils_exception_sp_offset =
+    12;
+static constexpr dart::compiler::target::word TsanUtils_exception_fp_offset =
+    16;
 static constexpr dart::compiler::target::word TimelineStream_enabled_offset = 8;
 static constexpr dart::compiler::target::word TwoByteString_data_offset = 12;
 static constexpr dart::compiler::target::word Type_arguments_offset = 12;
@@ -3791,7 +3882,7 @@
     4, 12, 8, 16};
 static constexpr dart::compiler::target::word
     Thread_write_barrier_wrappers_thread_offset[] = {
-        716, 720, 724, 728, 732, -1, 736, -1, 740, 744, -1, -1, -1, -1, -1, -1};
+        720, 724, 728, 732, 736, -1, 740, -1, 744, 748, -1, -1, -1, -1, -1, -1};
 static constexpr dart::compiler::target::word AbstractType_InstanceSize = 12;
 static constexpr dart::compiler::target::word ApiError_InstanceSize = 8;
 static constexpr dart::compiler::target::word Array_header_size = 12;
@@ -3801,8 +3892,10 @@
 static constexpr dart::compiler::target::word Closure_InstanceSize = 28;
 static constexpr dart::compiler::target::word ClosureData_InstanceSize = 20;
 static constexpr dart::compiler::target::word CodeSourceMap_HeaderSize = 8;
-static constexpr dart::compiler::target::word CompressedStackMaps_HeaderSize =
-    8;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_ObjectHeaderSize = 4;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word Context_header_size = 12;
 static constexpr dart::compiler::target::word Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word DynamicLibrary_InstanceSize = 8;
@@ -3828,6 +3921,8 @@
     8;
 static constexpr dart::compiler::target::word
     InstructionsSection_UnalignedHeaderSize = 20;
+static constexpr dart::compiler::target::word InstructionsTable_InstanceSize =
+    24;
 static constexpr dart::compiler::target::word Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word Integer_InstanceSize = 4;
 static constexpr dart::compiler::target::word KernelProgramInfo_InstanceSize =
@@ -3873,7 +3968,7 @@
     12;
 static constexpr dart::compiler::target::word UnlinkedCall_InstanceSize = 16;
 static constexpr dart::compiler::target::word UnwindError_InstanceSize = 12;
-static constexpr dart::compiler::target::word UserTag_InstanceSize = 12;
+static constexpr dart::compiler::target::word UserTag_InstanceSize = 16;
 static constexpr dart::compiler::target::word WeakProperty_InstanceSize = 16;
 static constexpr dart::compiler::target::word
     WeakSerializationReference_InstanceSize = 12;
@@ -3898,10 +3993,6 @@
     ExceptionHandlers_elements_start_offset = 24;
 static constexpr dart::compiler::target::word ExceptionHandlers_element_size =
     12;
-static constexpr dart::compiler::target::word
-    InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word InstructionsTable_element_size =
-    4;
 static constexpr dart::compiler::target::word ObjectPool_elements_start_offset =
     16;
 static constexpr dart::compiler::target::word ObjectPool_element_size = 8;
@@ -4107,11 +4198,11 @@
 static constexpr dart::compiler::target::word String_length_offset = 8;
 static constexpr dart::compiler::target::word SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    Thread_AllocateArray_entry_point_offset = 728;
+    Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word Thread_active_exception_offset =
-    1496;
-static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
     1504;
+static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
+    1512;
 static constexpr dart::compiler::target::word
     Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -4137,22 +4228,22 @@
 static constexpr dart::compiler::target::word
     Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word Thread_api_top_scope_offset =
-    1576;
+    1584;
 static constexpr dart::compiler::target::word
-    Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word Thread_bool_false_offset = 216;
 static constexpr dart::compiler::target::word Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_stub_offset = 264;
-static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1592;
+static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1624;
 static constexpr dart::compiler::target::word
     Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    Thread_double_truncate_round_supported_offset = 1584;
+    Thread_double_truncate_round_supported_offset = 1592;
 static constexpr dart::compiler::target::word Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word Thread_optimize_stub_offset = 440;
@@ -4161,14 +4252,14 @@
 static constexpr dart::compiler::target::word Thread_deoptimize_stub_offset =
     448;
 static constexpr dart::compiler::target::word Thread_double_abs_address_offset =
-    688;
+    696;
 static constexpr dart::compiler::target::word
-    Thread_double_negate_address_offset = 680;
+    Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word Thread_execution_state_offset =
-    1536;
+    1544;
 static constexpr dart::compiler::target::word
     Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -4180,22 +4271,22 @@
 static constexpr dart::compiler::target::word
     Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    Thread_float_absolute_address_offset = 712;
+    Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    Thread_float_negate_address_offset = 704;
+    Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word Thread_float_not_address_offset =
-    696;
+    704;
 static constexpr dart::compiler::target::word
-    Thread_float_zerow_address_offset = 720;
+    Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word Thread_global_object_pool_offset =
-    1512;
+    1520;
 static constexpr dart::compiler::target::word
     Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word Thread_exit_through_ffi_offset =
-    1568;
+    1576;
 static constexpr dart::compiler::target::word Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word Thread_isolate_group_offset =
-    1600;
+    1632;
 static constexpr dart::compiler::target::word Thread_field_table_values_offset =
     128;
 static constexpr dart::compiler::target::word
@@ -4213,7 +4304,7 @@
 static constexpr dart::compiler::target::word
     Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -4236,16 +4327,16 @@
     Thread_range_error_shared_without_fpu_regs_stub_offset = 336;
 static constexpr dart::compiler::target::word Thread_object_null_offset = 200;
 static constexpr dart::compiler::target::word
-    Thread_predefined_symbols_address_offset = 664;
-static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1520;
+    Thread_predefined_symbols_address_offset = 672;
+static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1528;
 static constexpr dart::compiler::target::word
-    Thread_saved_shadow_call_stack_offset = 1528;
+    Thread_saved_shadow_call_stack_offset = 1536;
 static constexpr dart::compiler::target::word Thread_safepoint_state_offset =
-    1544;
+    1552;
 static constexpr dart::compiler::target::word
     Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    Thread_slow_type_test_entry_point_offset = 632;
+    Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word Thread_stack_limit_offset = 56;
 static constexpr dart::compiler::target::word Thread_saved_stack_limit_offset =
     112;
@@ -4278,9 +4369,23 @@
     64;
 static constexpr dart::compiler::target::word Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word Thread_callback_code_offset =
-    1552;
+    1560;
 static constexpr dart::compiler::target::word
-    Thread_callback_stack_return_offset = 1560;
+    Thread_callback_stack_return_offset = 1568;
+static constexpr dart::compiler::target::word Thread_random_offset = 1600;
+static constexpr dart::compiler::target::word
+    Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word Thread_tsan_utils_offset = 1608;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_function_offset =
+    0;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_buffer_offset =
+    8;
+static constexpr dart::compiler::target::word TsanUtils_exception_pc_offset =
+    16;
+static constexpr dart::compiler::target::word TsanUtils_exception_sp_offset =
+    24;
+static constexpr dart::compiler::target::word TsanUtils_exception_fp_offset =
+    32;
 static constexpr dart::compiler::target::word TimelineStream_enabled_offset =
     16;
 static constexpr dart::compiler::target::word TwoByteString_data_offset = 16;
@@ -4341,8 +4446,8 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, -1,   -1,   1440, 1448,
-        1456, 1464, 1472, -1,   1480, 1488, -1,   -1};
+        1416, 1424, 1432, 1440, -1,   -1,   1448, 1456,
+        1464, 1472, 1480, -1,   1488, 1496, -1,   -1};
 static constexpr dart::compiler::target::word AbstractType_InstanceSize = 24;
 static constexpr dart::compiler::target::word ApiError_InstanceSize = 16;
 static constexpr dart::compiler::target::word Array_header_size = 24;
@@ -4352,8 +4457,10 @@
 static constexpr dart::compiler::target::word Closure_InstanceSize = 56;
 static constexpr dart::compiler::target::word ClosureData_InstanceSize = 40;
 static constexpr dart::compiler::target::word CodeSourceMap_HeaderSize = 16;
-static constexpr dart::compiler::target::word CompressedStackMaps_HeaderSize =
-    16;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word Context_header_size = 24;
 static constexpr dart::compiler::target::word Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word DynamicLibrary_InstanceSize = 16;
@@ -4379,6 +4486,8 @@
     16;
 static constexpr dart::compiler::target::word
     InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word InstructionsTable_InstanceSize =
+    48;
 static constexpr dart::compiler::target::word Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word KernelProgramInfo_InstanceSize =
@@ -4425,7 +4534,7 @@
     24;
 static constexpr dart::compiler::target::word UnlinkedCall_InstanceSize = 32;
 static constexpr dart::compiler::target::word UnwindError_InstanceSize = 24;
-static constexpr dart::compiler::target::word UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word WeakProperty_InstanceSize = 32;
 static constexpr dart::compiler::target::word
     WeakSerializationReference_InstanceSize = 24;
@@ -4450,10 +4559,6 @@
     ExceptionHandlers_elements_start_offset = 12;
 static constexpr dart::compiler::target::word ExceptionHandlers_element_size =
     12;
-static constexpr dart::compiler::target::word
-    InstructionsTable_elements_start_offset = 20;
-static constexpr dart::compiler::target::word InstructionsTable_element_size =
-    4;
 static constexpr dart::compiler::target::word ObjectPool_elements_start_offset =
     8;
 static constexpr dart::compiler::target::word ObjectPool_element_size = 4;
@@ -4654,11 +4759,11 @@
 static constexpr dart::compiler::target::word String_length_offset = 4;
 static constexpr dart::compiler::target::word SubtypeTestCache_cache_offset = 4;
 static constexpr dart::compiler::target::word
-    Thread_AllocateArray_entry_point_offset = 376;
+    Thread_AllocateArray_entry_point_offset = 380;
 static constexpr dart::compiler::target::word Thread_active_exception_offset =
-    716;
-static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
     720;
+static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
+    724;
 static constexpr dart::compiler::target::word
     Thread_array_write_barrier_code_offset = 128;
 static constexpr dart::compiler::target::word
@@ -4683,22 +4788,22 @@
     Thread_allocate_object_slow_entry_point_offset = 296;
 static constexpr dart::compiler::target::word
     Thread_allocate_object_slow_stub_offset = 204;
-static constexpr dart::compiler::target::word Thread_api_top_scope_offset = 756;
+static constexpr dart::compiler::target::word Thread_api_top_scope_offset = 760;
 static constexpr dart::compiler::target::word
-    Thread_auto_scope_native_wrapper_entry_point_offset = 340;
+    Thread_auto_scope_native_wrapper_entry_point_offset = 344;
 static constexpr dart::compiler::target::word Thread_bool_false_offset = 120;
 static constexpr dart::compiler::target::word Thread_bool_true_offset = 116;
 static constexpr dart::compiler::target::word
-    Thread_bootstrap_native_wrapper_entry_point_offset = 332;
+    Thread_bootstrap_native_wrapper_entry_point_offset = 336;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_entry_point_offset = 276;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_stub_offset = 144;
-static constexpr dart::compiler::target::word Thread_dart_stream_offset = 768;
+static constexpr dart::compiler::target::word Thread_dart_stream_offset = 784;
 static constexpr dart::compiler::target::word
     Thread_dispatch_table_array_offset = 44;
 static constexpr dart::compiler::target::word
-    Thread_double_truncate_round_supported_offset = 760;
+    Thread_double_truncate_round_supported_offset = 764;
 static constexpr dart::compiler::target::word Thread_optimize_entry_offset =
     316;
 static constexpr dart::compiler::target::word Thread_optimize_stub_offset = 232;
@@ -4707,14 +4812,14 @@
 static constexpr dart::compiler::target::word Thread_deoptimize_stub_offset =
     236;
 static constexpr dart::compiler::target::word Thread_double_abs_address_offset =
-    356;
+    360;
 static constexpr dart::compiler::target::word
-    Thread_double_negate_address_offset = 352;
+    Thread_double_negate_address_offset = 356;
 static constexpr dart::compiler::target::word Thread_end_offset = 52;
 static constexpr dart::compiler::target::word
     Thread_enter_safepoint_stub_offset = 256;
 static constexpr dart::compiler::target::word Thread_execution_state_offset =
-    736;
+    740;
 static constexpr dart::compiler::target::word
     Thread_exit_safepoint_stub_offset = 260;
 static constexpr dart::compiler::target::word
@@ -4726,21 +4831,21 @@
 static constexpr dart::compiler::target::word
     Thread_fix_callers_target_code_offset = 132;
 static constexpr dart::compiler::target::word
-    Thread_float_absolute_address_offset = 368;
+    Thread_float_absolute_address_offset = 372;
 static constexpr dart::compiler::target::word
-    Thread_float_negate_address_offset = 364;
+    Thread_float_negate_address_offset = 368;
 static constexpr dart::compiler::target::word Thread_float_not_address_offset =
-    360;
+    364;
 static constexpr dart::compiler::target::word
-    Thread_float_zerow_address_offset = 372;
+    Thread_float_zerow_address_offset = 376;
 static constexpr dart::compiler::target::word Thread_global_object_pool_offset =
-    724;
+    728;
 static constexpr dart::compiler::target::word
     Thread_invoke_dart_code_stub_offset = 140;
 static constexpr dart::compiler::target::word Thread_exit_through_ffi_offset =
-    752;
+    756;
 static constexpr dart::compiler::target::word Thread_isolate_offset = 40;
-static constexpr dart::compiler::target::word Thread_isolate_group_offset = 772;
+static constexpr dart::compiler::target::word Thread_isolate_group_offset = 788;
 static constexpr dart::compiler::target::word Thread_field_table_values_offset =
     64;
 static constexpr dart::compiler::target::word
@@ -4758,7 +4863,7 @@
 static constexpr dart::compiler::target::word
     Thread_switchable_call_miss_stub_offset = 216;
 static constexpr dart::compiler::target::word
-    Thread_no_scope_native_wrapper_entry_point_offset = 336;
+    Thread_no_scope_native_wrapper_entry_point_offset = 340;
 static constexpr dart::compiler::target::word
     Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 152;
 static constexpr dart::compiler::target::word
@@ -4781,16 +4886,16 @@
     Thread_range_error_shared_without_fpu_regs_stub_offset = 180;
 static constexpr dart::compiler::target::word Thread_object_null_offset = 112;
 static constexpr dart::compiler::target::word
-    Thread_predefined_symbols_address_offset = 344;
-static constexpr dart::compiler::target::word Thread_resume_pc_offset = 728;
+    Thread_predefined_symbols_address_offset = 348;
+static constexpr dart::compiler::target::word Thread_resume_pc_offset = 732;
 static constexpr dart::compiler::target::word
-    Thread_saved_shadow_call_stack_offset = 732;
+    Thread_saved_shadow_call_stack_offset = 736;
 static constexpr dart::compiler::target::word Thread_safepoint_state_offset =
-    740;
+    744;
 static constexpr dart::compiler::target::word
     Thread_slow_type_test_stub_offset = 248;
 static constexpr dart::compiler::target::word
-    Thread_slow_type_test_entry_point_offset = 328;
+    Thread_slow_type_test_entry_point_offset = 332;
 static constexpr dart::compiler::target::word Thread_stack_limit_offset = 28;
 static constexpr dart::compiler::target::word Thread_saved_stack_limit_offset =
     56;
@@ -4822,9 +4927,22 @@
 static constexpr dart::compiler::target::word Thread_write_barrier_mask_offset =
     32;
 static constexpr dart::compiler::target::word Thread_heap_base_offset = 36;
-static constexpr dart::compiler::target::word Thread_callback_code_offset = 744;
+static constexpr dart::compiler::target::word Thread_callback_code_offset = 748;
 static constexpr dart::compiler::target::word
-    Thread_callback_stack_return_offset = 748;
+    Thread_callback_stack_return_offset = 752;
+static constexpr dart::compiler::target::word Thread_random_offset = 768;
+static constexpr dart::compiler::target::word
+    Thread_jump_to_frame_entry_point_offset = 328;
+static constexpr dart::compiler::target::word Thread_tsan_utils_offset = 776;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_function_offset =
+    0;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_buffer_offset =
+    4;
+static constexpr dart::compiler::target::word TsanUtils_exception_pc_offset = 8;
+static constexpr dart::compiler::target::word TsanUtils_exception_sp_offset =
+    12;
+static constexpr dart::compiler::target::word TsanUtils_exception_fp_offset =
+    16;
 static constexpr dart::compiler::target::word TimelineStream_enabled_offset = 8;
 static constexpr dart::compiler::target::word TwoByteString_data_offset = 12;
 static constexpr dart::compiler::target::word Type_arguments_offset = 12;
@@ -4891,8 +5009,10 @@
 static constexpr dart::compiler::target::word Closure_InstanceSize = 28;
 static constexpr dart::compiler::target::word ClosureData_InstanceSize = 20;
 static constexpr dart::compiler::target::word CodeSourceMap_HeaderSize = 8;
-static constexpr dart::compiler::target::word CompressedStackMaps_HeaderSize =
-    8;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_ObjectHeaderSize = 4;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word Context_header_size = 12;
 static constexpr dart::compiler::target::word Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word DynamicLibrary_InstanceSize = 8;
@@ -4918,6 +5038,8 @@
     8;
 static constexpr dart::compiler::target::word
     InstructionsSection_UnalignedHeaderSize = 20;
+static constexpr dart::compiler::target::word InstructionsTable_InstanceSize =
+    24;
 static constexpr dart::compiler::target::word Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word Integer_InstanceSize = 4;
 static constexpr dart::compiler::target::word KernelProgramInfo_InstanceSize =
@@ -4963,7 +5085,7 @@
     12;
 static constexpr dart::compiler::target::word UnlinkedCall_InstanceSize = 16;
 static constexpr dart::compiler::target::word UnwindError_InstanceSize = 12;
-static constexpr dart::compiler::target::word UserTag_InstanceSize = 12;
+static constexpr dart::compiler::target::word UserTag_InstanceSize = 16;
 static constexpr dart::compiler::target::word WeakProperty_InstanceSize = 16;
 static constexpr dart::compiler::target::word
     WeakSerializationReference_InstanceSize = 12;
@@ -4988,10 +5110,6 @@
     ExceptionHandlers_elements_start_offset = 24;
 static constexpr dart::compiler::target::word ExceptionHandlers_element_size =
     12;
-static constexpr dart::compiler::target::word
-    InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word InstructionsTable_element_size =
-    4;
 static constexpr dart::compiler::target::word ObjectPool_elements_start_offset =
     16;
 static constexpr dart::compiler::target::word ObjectPool_element_size = 8;
@@ -5197,11 +5315,11 @@
 static constexpr dart::compiler::target::word String_length_offset = 8;
 static constexpr dart::compiler::target::word SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    Thread_AllocateArray_entry_point_offset = 728;
+    Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word Thread_active_exception_offset =
-    1560;
-static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
     1568;
+static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
+    1576;
 static constexpr dart::compiler::target::word
     Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -5227,22 +5345,22 @@
 static constexpr dart::compiler::target::word
     Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word Thread_api_top_scope_offset =
-    1640;
+    1648;
 static constexpr dart::compiler::target::word
-    Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word Thread_bool_false_offset = 216;
 static constexpr dart::compiler::target::word Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_stub_offset = 264;
-static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1656;
+static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1688;
 static constexpr dart::compiler::target::word
     Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    Thread_double_truncate_round_supported_offset = 1648;
+    Thread_double_truncate_round_supported_offset = 1656;
 static constexpr dart::compiler::target::word Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word Thread_optimize_stub_offset = 440;
@@ -5251,14 +5369,14 @@
 static constexpr dart::compiler::target::word Thread_deoptimize_stub_offset =
     448;
 static constexpr dart::compiler::target::word Thread_double_abs_address_offset =
-    688;
+    696;
 static constexpr dart::compiler::target::word
-    Thread_double_negate_address_offset = 680;
+    Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word Thread_execution_state_offset =
-    1600;
+    1608;
 static constexpr dart::compiler::target::word
     Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -5270,22 +5388,22 @@
 static constexpr dart::compiler::target::word
     Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    Thread_float_absolute_address_offset = 712;
+    Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    Thread_float_negate_address_offset = 704;
+    Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word Thread_float_not_address_offset =
-    696;
+    704;
 static constexpr dart::compiler::target::word
-    Thread_float_zerow_address_offset = 720;
+    Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word Thread_global_object_pool_offset =
-    1576;
+    1584;
 static constexpr dart::compiler::target::word
     Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word Thread_exit_through_ffi_offset =
-    1632;
+    1640;
 static constexpr dart::compiler::target::word Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word Thread_isolate_group_offset =
-    1664;
+    1696;
 static constexpr dart::compiler::target::word Thread_field_table_values_offset =
     128;
 static constexpr dart::compiler::target::word
@@ -5303,7 +5421,7 @@
 static constexpr dart::compiler::target::word
     Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -5326,16 +5444,16 @@
     Thread_range_error_shared_without_fpu_regs_stub_offset = 336;
 static constexpr dart::compiler::target::word Thread_object_null_offset = 200;
 static constexpr dart::compiler::target::word
-    Thread_predefined_symbols_address_offset = 664;
-static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1584;
+    Thread_predefined_symbols_address_offset = 672;
+static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1592;
 static constexpr dart::compiler::target::word
-    Thread_saved_shadow_call_stack_offset = 1592;
+    Thread_saved_shadow_call_stack_offset = 1600;
 static constexpr dart::compiler::target::word Thread_safepoint_state_offset =
-    1608;
+    1616;
 static constexpr dart::compiler::target::word
     Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    Thread_slow_type_test_entry_point_offset = 632;
+    Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word Thread_stack_limit_offset = 56;
 static constexpr dart::compiler::target::word Thread_saved_stack_limit_offset =
     112;
@@ -5368,9 +5486,23 @@
     64;
 static constexpr dart::compiler::target::word Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word Thread_callback_code_offset =
-    1616;
+    1624;
 static constexpr dart::compiler::target::word
-    Thread_callback_stack_return_offset = 1624;
+    Thread_callback_stack_return_offset = 1632;
+static constexpr dart::compiler::target::word Thread_random_offset = 1664;
+static constexpr dart::compiler::target::word
+    Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word Thread_tsan_utils_offset = 1672;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_function_offset =
+    0;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_buffer_offset =
+    8;
+static constexpr dart::compiler::target::word TsanUtils_exception_pc_offset =
+    16;
+static constexpr dart::compiler::target::word TsanUtils_exception_sp_offset =
+    24;
+static constexpr dart::compiler::target::word TsanUtils_exception_fp_offset =
+    32;
 static constexpr dart::compiler::target::word TimelineStream_enabled_offset =
     16;
 static constexpr dart::compiler::target::word TwoByteString_data_offset = 16;
@@ -5431,9 +5563,9 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488,
-        1496, 1504, 1512, 1520, -1,   -1,   -1,   -1,   1528, 1536, -1,
-        -1,   1544, 1552, 1560, -1,   -1,   -1,   -1,   -1,   -1};
+        1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488, 1496,
+        1504, 1512, 1520, 1528, -1,   -1,   -1,   -1,   1536, 1544, -1,
+        -1,   1552, 1560, 1568, -1,   -1,   -1,   -1,   -1,   -1};
 static constexpr dart::compiler::target::word AbstractType_InstanceSize = 24;
 static constexpr dart::compiler::target::word ApiError_InstanceSize = 16;
 static constexpr dart::compiler::target::word Array_header_size = 24;
@@ -5443,8 +5575,10 @@
 static constexpr dart::compiler::target::word Closure_InstanceSize = 56;
 static constexpr dart::compiler::target::word ClosureData_InstanceSize = 40;
 static constexpr dart::compiler::target::word CodeSourceMap_HeaderSize = 16;
-static constexpr dart::compiler::target::word CompressedStackMaps_HeaderSize =
-    16;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word Context_header_size = 24;
 static constexpr dart::compiler::target::word Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word DynamicLibrary_InstanceSize = 16;
@@ -5470,6 +5604,8 @@
     16;
 static constexpr dart::compiler::target::word
     InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word InstructionsTable_InstanceSize =
+    48;
 static constexpr dart::compiler::target::word Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word KernelProgramInfo_InstanceSize =
@@ -5516,7 +5652,7 @@
     24;
 static constexpr dart::compiler::target::word UnlinkedCall_InstanceSize = 32;
 static constexpr dart::compiler::target::word UnwindError_InstanceSize = 24;
-static constexpr dart::compiler::target::word UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word WeakProperty_InstanceSize = 32;
 static constexpr dart::compiler::target::word
     WeakSerializationReference_InstanceSize = 24;
@@ -5541,10 +5677,6 @@
     ExceptionHandlers_elements_start_offset = 16;
 static constexpr dart::compiler::target::word ExceptionHandlers_element_size =
     12;
-static constexpr dart::compiler::target::word
-    InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word InstructionsTable_element_size =
-    4;
 static constexpr dart::compiler::target::word ObjectPool_elements_start_offset =
     16;
 static constexpr dart::compiler::target::word ObjectPool_element_size = 8;
@@ -5747,11 +5879,11 @@
 static constexpr dart::compiler::target::word String_length_offset = 8;
 static constexpr dart::compiler::target::word SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    Thread_AllocateArray_entry_point_offset = 728;
+    Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word Thread_active_exception_offset =
-    1496;
-static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
     1504;
+static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
+    1512;
 static constexpr dart::compiler::target::word
     Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -5777,22 +5909,22 @@
 static constexpr dart::compiler::target::word
     Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word Thread_api_top_scope_offset =
-    1576;
+    1584;
 static constexpr dart::compiler::target::word
-    Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word Thread_bool_false_offset = 216;
 static constexpr dart::compiler::target::word Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_stub_offset = 264;
-static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1592;
+static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1624;
 static constexpr dart::compiler::target::word
     Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    Thread_double_truncate_round_supported_offset = 1584;
+    Thread_double_truncate_round_supported_offset = 1592;
 static constexpr dart::compiler::target::word Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word Thread_optimize_stub_offset = 440;
@@ -5801,14 +5933,14 @@
 static constexpr dart::compiler::target::word Thread_deoptimize_stub_offset =
     448;
 static constexpr dart::compiler::target::word Thread_double_abs_address_offset =
-    688;
+    696;
 static constexpr dart::compiler::target::word
-    Thread_double_negate_address_offset = 680;
+    Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word Thread_execution_state_offset =
-    1536;
+    1544;
 static constexpr dart::compiler::target::word
     Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -5820,22 +5952,22 @@
 static constexpr dart::compiler::target::word
     Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    Thread_float_absolute_address_offset = 712;
+    Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    Thread_float_negate_address_offset = 704;
+    Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word Thread_float_not_address_offset =
-    696;
+    704;
 static constexpr dart::compiler::target::word
-    Thread_float_zerow_address_offset = 720;
+    Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word Thread_global_object_pool_offset =
-    1512;
+    1520;
 static constexpr dart::compiler::target::word
     Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word Thread_exit_through_ffi_offset =
-    1568;
+    1576;
 static constexpr dart::compiler::target::word Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word Thread_isolate_group_offset =
-    1600;
+    1632;
 static constexpr dart::compiler::target::word Thread_field_table_values_offset =
     128;
 static constexpr dart::compiler::target::word
@@ -5853,7 +5985,7 @@
 static constexpr dart::compiler::target::word
     Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -5876,16 +6008,16 @@
     Thread_range_error_shared_without_fpu_regs_stub_offset = 336;
 static constexpr dart::compiler::target::word Thread_object_null_offset = 200;
 static constexpr dart::compiler::target::word
-    Thread_predefined_symbols_address_offset = 664;
-static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1520;
+    Thread_predefined_symbols_address_offset = 672;
+static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1528;
 static constexpr dart::compiler::target::word
-    Thread_saved_shadow_call_stack_offset = 1528;
+    Thread_saved_shadow_call_stack_offset = 1536;
 static constexpr dart::compiler::target::word Thread_safepoint_state_offset =
-    1544;
+    1552;
 static constexpr dart::compiler::target::word
     Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    Thread_slow_type_test_entry_point_offset = 632;
+    Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word Thread_stack_limit_offset = 56;
 static constexpr dart::compiler::target::word Thread_saved_stack_limit_offset =
     112;
@@ -5918,9 +6050,23 @@
     64;
 static constexpr dart::compiler::target::word Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word Thread_callback_code_offset =
-    1552;
+    1560;
 static constexpr dart::compiler::target::word
-    Thread_callback_stack_return_offset = 1560;
+    Thread_callback_stack_return_offset = 1568;
+static constexpr dart::compiler::target::word Thread_random_offset = 1600;
+static constexpr dart::compiler::target::word
+    Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word Thread_tsan_utils_offset = 1608;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_function_offset =
+    0;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_buffer_offset =
+    8;
+static constexpr dart::compiler::target::word TsanUtils_exception_pc_offset =
+    16;
+static constexpr dart::compiler::target::word TsanUtils_exception_sp_offset =
+    24;
+static constexpr dart::compiler::target::word TsanUtils_exception_fp_offset =
+    32;
 static constexpr dart::compiler::target::word TimelineStream_enabled_offset =
     16;
 static constexpr dart::compiler::target::word TwoByteString_data_offset = 16;
@@ -5981,8 +6127,8 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, -1,   -1,   1440, 1448,
-        1456, 1464, 1472, -1,   1480, 1488, -1,   -1};
+        1416, 1424, 1432, 1440, -1,   -1,   1448, 1456,
+        1464, 1472, 1480, -1,   1488, 1496, -1,   -1};
 static constexpr dart::compiler::target::word AbstractType_InstanceSize = 24;
 static constexpr dart::compiler::target::word ApiError_InstanceSize = 16;
 static constexpr dart::compiler::target::word Array_header_size = 16;
@@ -5992,8 +6138,10 @@
 static constexpr dart::compiler::target::word Closure_InstanceSize = 32;
 static constexpr dart::compiler::target::word ClosureData_InstanceSize = 24;
 static constexpr dart::compiler::target::word CodeSourceMap_HeaderSize = 16;
-static constexpr dart::compiler::target::word CompressedStackMaps_HeaderSize =
-    16;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word Context_header_size = 16;
 static constexpr dart::compiler::target::word Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word DynamicLibrary_InstanceSize = 16;
@@ -6019,6 +6167,8 @@
     16;
 static constexpr dart::compiler::target::word
     InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word InstructionsTable_InstanceSize =
+    48;
 static constexpr dart::compiler::target::word Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word KernelProgramInfo_InstanceSize =
@@ -6065,7 +6215,7 @@
     16;
 static constexpr dart::compiler::target::word UnlinkedCall_InstanceSize = 32;
 static constexpr dart::compiler::target::word UnwindError_InstanceSize = 16;
-static constexpr dart::compiler::target::word UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word WeakProperty_InstanceSize = 24;
 static constexpr dart::compiler::target::word
     WeakSerializationReference_InstanceSize = 16;
@@ -6090,10 +6240,6 @@
     ExceptionHandlers_elements_start_offset = 16;
 static constexpr dart::compiler::target::word ExceptionHandlers_element_size =
     12;
-static constexpr dart::compiler::target::word
-    InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word InstructionsTable_element_size =
-    4;
 static constexpr dart::compiler::target::word ObjectPool_elements_start_offset =
     16;
 static constexpr dart::compiler::target::word ObjectPool_element_size = 8;
@@ -6296,11 +6442,11 @@
 static constexpr dart::compiler::target::word String_length_offset = 8;
 static constexpr dart::compiler::target::word SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    Thread_AllocateArray_entry_point_offset = 728;
+    Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word Thread_active_exception_offset =
-    1560;
-static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
     1568;
+static constexpr dart::compiler::target::word Thread_active_stacktrace_offset =
+    1576;
 static constexpr dart::compiler::target::word
     Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -6326,22 +6472,22 @@
 static constexpr dart::compiler::target::word
     Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word Thread_api_top_scope_offset =
-    1640;
+    1648;
 static constexpr dart::compiler::target::word
-    Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word Thread_bool_false_offset = 216;
 static constexpr dart::compiler::target::word Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     Thread_call_to_runtime_stub_offset = 264;
-static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1656;
+static constexpr dart::compiler::target::word Thread_dart_stream_offset = 1688;
 static constexpr dart::compiler::target::word
     Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    Thread_double_truncate_round_supported_offset = 1648;
+    Thread_double_truncate_round_supported_offset = 1656;
 static constexpr dart::compiler::target::word Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word Thread_optimize_stub_offset = 440;
@@ -6350,14 +6496,14 @@
 static constexpr dart::compiler::target::word Thread_deoptimize_stub_offset =
     448;
 static constexpr dart::compiler::target::word Thread_double_abs_address_offset =
-    688;
+    696;
 static constexpr dart::compiler::target::word
-    Thread_double_negate_address_offset = 680;
+    Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word Thread_execution_state_offset =
-    1600;
+    1608;
 static constexpr dart::compiler::target::word
     Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -6369,22 +6515,22 @@
 static constexpr dart::compiler::target::word
     Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    Thread_float_absolute_address_offset = 712;
+    Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    Thread_float_negate_address_offset = 704;
+    Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word Thread_float_not_address_offset =
-    696;
+    704;
 static constexpr dart::compiler::target::word
-    Thread_float_zerow_address_offset = 720;
+    Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word Thread_global_object_pool_offset =
-    1576;
+    1584;
 static constexpr dart::compiler::target::word
     Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word Thread_exit_through_ffi_offset =
-    1632;
+    1640;
 static constexpr dart::compiler::target::word Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word Thread_isolate_group_offset =
-    1664;
+    1696;
 static constexpr dart::compiler::target::word Thread_field_table_values_offset =
     128;
 static constexpr dart::compiler::target::word
@@ -6402,7 +6548,7 @@
 static constexpr dart::compiler::target::word
     Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -6425,16 +6571,16 @@
     Thread_range_error_shared_without_fpu_regs_stub_offset = 336;
 static constexpr dart::compiler::target::word Thread_object_null_offset = 200;
 static constexpr dart::compiler::target::word
-    Thread_predefined_symbols_address_offset = 664;
-static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1584;
+    Thread_predefined_symbols_address_offset = 672;
+static constexpr dart::compiler::target::word Thread_resume_pc_offset = 1592;
 static constexpr dart::compiler::target::word
-    Thread_saved_shadow_call_stack_offset = 1592;
+    Thread_saved_shadow_call_stack_offset = 1600;
 static constexpr dart::compiler::target::word Thread_safepoint_state_offset =
-    1608;
+    1616;
 static constexpr dart::compiler::target::word
     Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    Thread_slow_type_test_entry_point_offset = 632;
+    Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word Thread_stack_limit_offset = 56;
 static constexpr dart::compiler::target::word Thread_saved_stack_limit_offset =
     112;
@@ -6467,9 +6613,23 @@
     64;
 static constexpr dart::compiler::target::word Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word Thread_callback_code_offset =
-    1616;
+    1624;
 static constexpr dart::compiler::target::word
-    Thread_callback_stack_return_offset = 1624;
+    Thread_callback_stack_return_offset = 1632;
+static constexpr dart::compiler::target::word Thread_random_offset = 1664;
+static constexpr dart::compiler::target::word
+    Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word Thread_tsan_utils_offset = 1672;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_function_offset =
+    0;
+static constexpr dart::compiler::target::word TsanUtils_setjmp_buffer_offset =
+    8;
+static constexpr dart::compiler::target::word TsanUtils_exception_pc_offset =
+    16;
+static constexpr dart::compiler::target::word TsanUtils_exception_sp_offset =
+    24;
+static constexpr dart::compiler::target::word TsanUtils_exception_fp_offset =
+    32;
 static constexpr dart::compiler::target::word TimelineStream_enabled_offset =
     16;
 static constexpr dart::compiler::target::word TwoByteString_data_offset = 16;
@@ -6530,9 +6690,9 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488,
-        1496, 1504, 1512, 1520, -1,   -1,   -1,   -1,   1528, 1536, -1,
-        -1,   1544, 1552, 1560, -1,   -1,   -1,   -1,   -1,   -1};
+        1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488, 1496,
+        1504, 1512, 1520, 1528, -1,   -1,   -1,   -1,   1536, 1544, -1,
+        -1,   1552, 1560, 1568, -1,   -1,   -1,   -1,   -1,   -1};
 static constexpr dart::compiler::target::word AbstractType_InstanceSize = 24;
 static constexpr dart::compiler::target::word ApiError_InstanceSize = 16;
 static constexpr dart::compiler::target::word Array_header_size = 16;
@@ -6542,8 +6702,10 @@
 static constexpr dart::compiler::target::word Closure_InstanceSize = 32;
 static constexpr dart::compiler::target::word ClosureData_InstanceSize = 24;
 static constexpr dart::compiler::target::word CodeSourceMap_HeaderSize = 16;
-static constexpr dart::compiler::target::word CompressedStackMaps_HeaderSize =
-    16;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word Context_header_size = 16;
 static constexpr dart::compiler::target::word Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word DynamicLibrary_InstanceSize = 16;
@@ -6569,6 +6731,8 @@
     16;
 static constexpr dart::compiler::target::word
     InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word InstructionsTable_InstanceSize =
+    48;
 static constexpr dart::compiler::target::word Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word KernelProgramInfo_InstanceSize =
@@ -6615,7 +6779,7 @@
     16;
 static constexpr dart::compiler::target::word UnlinkedCall_InstanceSize = 32;
 static constexpr dart::compiler::target::word UnwindError_InstanceSize = 16;
-static constexpr dart::compiler::target::word UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word WeakProperty_InstanceSize = 24;
 static constexpr dart::compiler::target::word
     WeakSerializationReference_InstanceSize = 16;
@@ -6649,10 +6813,6 @@
 static constexpr dart::compiler::target::word
     AOT_ExceptionHandlers_element_size = 12;
 static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_elements_start_offset = 20;
-static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_element_size = 4;
-static constexpr dart::compiler::target::word
     AOT_ObjectPool_elements_start_offset = 8;
 static constexpr dart::compiler::target::word AOT_ObjectPool_element_size = 4;
 static constexpr dart::compiler::target::word
@@ -6883,11 +7043,11 @@
 static constexpr dart::compiler::target::word
     AOT_SubtypeTestCache_cache_offset = 4;
 static constexpr dart::compiler::target::word
-    AOT_Thread_AllocateArray_entry_point_offset = 376;
+    AOT_Thread_AllocateArray_entry_point_offset = 380;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_exception_offset = 748;
+    AOT_Thread_active_exception_offset = 752;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_stacktrace_offset = 752;
+    AOT_Thread_active_stacktrace_offset = 756;
 static constexpr dart::compiler::target::word
     AOT_Thread_array_write_barrier_code_offset = 128;
 static constexpr dart::compiler::target::word
@@ -6913,24 +7073,24 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_allocate_object_slow_stub_offset = 204;
 static constexpr dart::compiler::target::word AOT_Thread_api_top_scope_offset =
-    788;
+    792;
 static constexpr dart::compiler::target::word
-    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 340;
+    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 344;
 static constexpr dart::compiler::target::word AOT_Thread_bool_false_offset =
     120;
 static constexpr dart::compiler::target::word AOT_Thread_bool_true_offset = 116;
 static constexpr dart::compiler::target::word
-    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 332;
+    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 336;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_entry_point_offset = 276;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_stub_offset = 144;
 static constexpr dart::compiler::target::word AOT_Thread_dart_stream_offset =
-    800;
+    816;
 static constexpr dart::compiler::target::word
     AOT_Thread_dispatch_table_array_offset = 44;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_truncate_round_supported_offset = 792;
+    AOT_Thread_double_truncate_round_supported_offset = 796;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_entry_offset =
     316;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_stub_offset =
@@ -6940,14 +7100,14 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_deoptimize_stub_offset = 236;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_abs_address_offset = 356;
+    AOT_Thread_double_abs_address_offset = 360;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_negate_address_offset = 352;
+    AOT_Thread_double_negate_address_offset = 356;
 static constexpr dart::compiler::target::word AOT_Thread_end_offset = 52;
 static constexpr dart::compiler::target::word
     AOT_Thread_enter_safepoint_stub_offset = 256;
 static constexpr dart::compiler::target::word
-    AOT_Thread_execution_state_offset = 768;
+    AOT_Thread_execution_state_offset = 772;
 static constexpr dart::compiler::target::word
     AOT_Thread_exit_safepoint_stub_offset = 260;
 static constexpr dart::compiler::target::word
@@ -6959,22 +7119,22 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_fix_callers_target_code_offset = 132;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_absolute_address_offset = 368;
+    AOT_Thread_float_absolute_address_offset = 372;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_negate_address_offset = 364;
+    AOT_Thread_float_negate_address_offset = 368;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_not_address_offset = 360;
+    AOT_Thread_float_not_address_offset = 364;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_zerow_address_offset = 372;
+    AOT_Thread_float_zerow_address_offset = 376;
 static constexpr dart::compiler::target::word
-    AOT_Thread_global_object_pool_offset = 756;
+    AOT_Thread_global_object_pool_offset = 760;
 static constexpr dart::compiler::target::word
     AOT_Thread_invoke_dart_code_stub_offset = 140;
 static constexpr dart::compiler::target::word
-    AOT_Thread_exit_through_ffi_offset = 784;
+    AOT_Thread_exit_through_ffi_offset = 788;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_offset = 40;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_group_offset =
-    804;
+    820;
 static constexpr dart::compiler::target::word
     AOT_Thread_field_table_values_offset = 64;
 static constexpr dart::compiler::target::word
@@ -6992,7 +7152,7 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_switchable_call_miss_stub_offset = 216;
 static constexpr dart::compiler::target::word
-    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 336;
+    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 340;
 static constexpr dart::compiler::target::word
     AOT_Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 152;
 static constexpr dart::compiler::target::word
@@ -7017,16 +7177,16 @@
 static constexpr dart::compiler::target::word AOT_Thread_object_null_offset =
     112;
 static constexpr dart::compiler::target::word
-    AOT_Thread_predefined_symbols_address_offset = 344;
-static constexpr dart::compiler::target::word AOT_Thread_resume_pc_offset = 760;
+    AOT_Thread_predefined_symbols_address_offset = 348;
+static constexpr dart::compiler::target::word AOT_Thread_resume_pc_offset = 764;
 static constexpr dart::compiler::target::word
-    AOT_Thread_saved_shadow_call_stack_offset = 764;
+    AOT_Thread_saved_shadow_call_stack_offset = 768;
 static constexpr dart::compiler::target::word
-    AOT_Thread_safepoint_state_offset = 772;
+    AOT_Thread_safepoint_state_offset = 776;
 static constexpr dart::compiler::target::word
     AOT_Thread_slow_type_test_stub_offset = 248;
 static constexpr dart::compiler::target::word
-    AOT_Thread_slow_type_test_entry_point_offset = 328;
+    AOT_Thread_slow_type_test_entry_point_offset = 332;
 static constexpr dart::compiler::target::word AOT_Thread_stack_limit_offset =
     28;
 static constexpr dart::compiler::target::word
@@ -7061,9 +7221,24 @@
     AOT_Thread_write_barrier_mask_offset = 32;
 static constexpr dart::compiler::target::word AOT_Thread_heap_base_offset = 36;
 static constexpr dart::compiler::target::word AOT_Thread_callback_code_offset =
-    776;
+    780;
 static constexpr dart::compiler::target::word
-    AOT_Thread_callback_stack_return_offset = 780;
+    AOT_Thread_callback_stack_return_offset = 784;
+static constexpr dart::compiler::target::word AOT_Thread_random_offset = 800;
+static constexpr dart::compiler::target::word
+    AOT_Thread_jump_to_frame_entry_point_offset = 328;
+static constexpr dart::compiler::target::word AOT_Thread_tsan_utils_offset =
+    808;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_function_offset = 0;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_buffer_offset = 4;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_pc_offset = 8;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_sp_offset = 12;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_fp_offset = 16;
 static constexpr dart::compiler::target::word
     AOT_TimelineStream_enabled_offset = 8;
 static constexpr dart::compiler::target::word AOT_TwoByteString_data_offset =
@@ -7136,7 +7311,7 @@
     4, 12, 8, 16};
 static constexpr dart::compiler::target::word
     AOT_Thread_write_barrier_wrappers_thread_offset[] = {
-        716, 720, 724, 728, 732, -1, 736, -1, 740, 744, -1, -1, -1, -1, -1, -1};
+        720, 724, 728, 732, 736, -1, 740, -1, 744, 748, -1, -1, -1, -1, -1, -1};
 static constexpr dart::compiler::target::word AOT_AbstractType_InstanceSize =
     12;
 static constexpr dart::compiler::target::word AOT_ApiError_InstanceSize = 8;
@@ -7148,7 +7323,9 @@
 static constexpr dart::compiler::target::word AOT_ClosureData_InstanceSize = 20;
 static constexpr dart::compiler::target::word AOT_CodeSourceMap_HeaderSize = 8;
 static constexpr dart::compiler::target::word
-    AOT_CompressedStackMaps_HeaderSize = 8;
+    AOT_CompressedStackMaps_ObjectHeaderSize = 4;
+static constexpr dart::compiler::target::word
+    AOT_CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word AOT_Context_header_size = 12;
 static constexpr dart::compiler::target::word AOT_Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word AOT_DynamicLibrary_InstanceSize =
@@ -7176,6 +7353,8 @@
     AOT_Instructions_UnalignedHeaderSize = 8;
 static constexpr dart::compiler::target::word
     AOT_InstructionsSection_UnalignedHeaderSize = 20;
+static constexpr dart::compiler::target::word
+    AOT_InstructionsTable_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_Integer_InstanceSize = 4;
 static constexpr dart::compiler::target::word
@@ -7232,7 +7411,7 @@
 static constexpr dart::compiler::target::word AOT_UnlinkedCall_InstanceSize =
     16;
 static constexpr dart::compiler::target::word AOT_UnwindError_InstanceSize = 12;
-static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 12;
+static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 16;
 static constexpr dart::compiler::target::word AOT_WeakProperty_InstanceSize =
     16;
 static constexpr dart::compiler::target::word
@@ -7263,10 +7442,6 @@
 static constexpr dart::compiler::target::word
     AOT_ExceptionHandlers_element_size = 12;
 static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_element_size = 4;
-static constexpr dart::compiler::target::word
     AOT_ObjectPool_elements_start_offset = 16;
 static constexpr dart::compiler::target::word AOT_ObjectPool_element_size = 8;
 static constexpr dart::compiler::target::word
@@ -7498,11 +7673,11 @@
 static constexpr dart::compiler::target::word
     AOT_SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    AOT_Thread_AllocateArray_entry_point_offset = 728;
+    AOT_Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_exception_offset = 1496;
+    AOT_Thread_active_exception_offset = 1504;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_stacktrace_offset = 1504;
+    AOT_Thread_active_stacktrace_offset = 1512;
 static constexpr dart::compiler::target::word
     AOT_Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -7528,24 +7703,24 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word AOT_Thread_api_top_scope_offset =
-    1576;
+    1584;
 static constexpr dart::compiler::target::word
-    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word AOT_Thread_bool_false_offset =
     216;
 static constexpr dart::compiler::target::word AOT_Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_stub_offset = 264;
 static constexpr dart::compiler::target::word AOT_Thread_dart_stream_offset =
-    1592;
+    1624;
 static constexpr dart::compiler::target::word
     AOT_Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_truncate_round_supported_offset = 1584;
+    AOT_Thread_double_truncate_round_supported_offset = 1592;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_stub_offset =
@@ -7555,14 +7730,14 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_deoptimize_stub_offset = 448;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_abs_address_offset = 688;
+    AOT_Thread_double_abs_address_offset = 696;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_negate_address_offset = 680;
+    AOT_Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word AOT_Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     AOT_Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word
-    AOT_Thread_execution_state_offset = 1536;
+    AOT_Thread_execution_state_offset = 1544;
 static constexpr dart::compiler::target::word
     AOT_Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -7574,22 +7749,22 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_absolute_address_offset = 712;
+    AOT_Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_negate_address_offset = 704;
+    AOT_Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_not_address_offset = 696;
+    AOT_Thread_float_not_address_offset = 704;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_zerow_address_offset = 720;
+    AOT_Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word
-    AOT_Thread_global_object_pool_offset = 1512;
+    AOT_Thread_global_object_pool_offset = 1520;
 static constexpr dart::compiler::target::word
     AOT_Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word
-    AOT_Thread_exit_through_ffi_offset = 1568;
+    AOT_Thread_exit_through_ffi_offset = 1576;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_group_offset =
-    1600;
+    1632;
 static constexpr dart::compiler::target::word
     AOT_Thread_field_table_values_offset = 128;
 static constexpr dart::compiler::target::word
@@ -7607,7 +7782,7 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     AOT_Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -7632,17 +7807,17 @@
 static constexpr dart::compiler::target::word AOT_Thread_object_null_offset =
     200;
 static constexpr dart::compiler::target::word
-    AOT_Thread_predefined_symbols_address_offset = 664;
+    AOT_Thread_predefined_symbols_address_offset = 672;
 static constexpr dart::compiler::target::word AOT_Thread_resume_pc_offset =
-    1520;
+    1528;
 static constexpr dart::compiler::target::word
-    AOT_Thread_saved_shadow_call_stack_offset = 1528;
+    AOT_Thread_saved_shadow_call_stack_offset = 1536;
 static constexpr dart::compiler::target::word
-    AOT_Thread_safepoint_state_offset = 1544;
+    AOT_Thread_safepoint_state_offset = 1552;
 static constexpr dart::compiler::target::word
     AOT_Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    AOT_Thread_slow_type_test_entry_point_offset = 632;
+    AOT_Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word AOT_Thread_stack_limit_offset =
     56;
 static constexpr dart::compiler::target::word
@@ -7677,9 +7852,24 @@
     AOT_Thread_write_barrier_mask_offset = 64;
 static constexpr dart::compiler::target::word AOT_Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word AOT_Thread_callback_code_offset =
-    1552;
+    1560;
 static constexpr dart::compiler::target::word
-    AOT_Thread_callback_stack_return_offset = 1560;
+    AOT_Thread_callback_stack_return_offset = 1568;
+static constexpr dart::compiler::target::word AOT_Thread_random_offset = 1600;
+static constexpr dart::compiler::target::word
+    AOT_Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word AOT_Thread_tsan_utils_offset =
+    1608;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_function_offset = 0;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_buffer_offset = 8;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_pc_offset = 16;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_sp_offset = 24;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_fp_offset = 32;
 static constexpr dart::compiler::target::word
     AOT_TimelineStream_enabled_offset = 16;
 static constexpr dart::compiler::target::word AOT_TwoByteString_data_offset =
@@ -7753,8 +7943,8 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     AOT_Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, -1,   -1,   1440, 1448,
-        1456, 1464, 1472, -1,   1480, 1488, -1,   -1};
+        1416, 1424, 1432, 1440, -1,   -1,   1448, 1456,
+        1464, 1472, 1480, -1,   1488, 1496, -1,   -1};
 static constexpr dart::compiler::target::word AOT_AbstractType_InstanceSize =
     24;
 static constexpr dart::compiler::target::word AOT_ApiError_InstanceSize = 16;
@@ -7766,7 +7956,9 @@
 static constexpr dart::compiler::target::word AOT_ClosureData_InstanceSize = 40;
 static constexpr dart::compiler::target::word AOT_CodeSourceMap_HeaderSize = 16;
 static constexpr dart::compiler::target::word
-    AOT_CompressedStackMaps_HeaderSize = 16;
+    AOT_CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    AOT_CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word AOT_Context_header_size = 24;
 static constexpr dart::compiler::target::word AOT_Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word AOT_DynamicLibrary_InstanceSize =
@@ -7794,6 +7986,8 @@
     AOT_Instructions_UnalignedHeaderSize = 16;
 static constexpr dart::compiler::target::word
     AOT_InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word
+    AOT_InstructionsTable_InstanceSize = 48;
 static constexpr dart::compiler::target::word AOT_Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word
@@ -7850,7 +8044,7 @@
 static constexpr dart::compiler::target::word AOT_UnlinkedCall_InstanceSize =
     32;
 static constexpr dart::compiler::target::word AOT_UnwindError_InstanceSize = 24;
-static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word AOT_WeakProperty_InstanceSize =
     32;
 static constexpr dart::compiler::target::word
@@ -7884,10 +8078,6 @@
 static constexpr dart::compiler::target::word
     AOT_ExceptionHandlers_element_size = 12;
 static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_element_size = 4;
-static constexpr dart::compiler::target::word
     AOT_ObjectPool_elements_start_offset = 16;
 static constexpr dart::compiler::target::word AOT_ObjectPool_element_size = 8;
 static constexpr dart::compiler::target::word
@@ -8119,11 +8309,11 @@
 static constexpr dart::compiler::target::word
     AOT_SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    AOT_Thread_AllocateArray_entry_point_offset = 728;
+    AOT_Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_exception_offset = 1560;
+    AOT_Thread_active_exception_offset = 1568;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_stacktrace_offset = 1568;
+    AOT_Thread_active_stacktrace_offset = 1576;
 static constexpr dart::compiler::target::word
     AOT_Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -8149,24 +8339,24 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word AOT_Thread_api_top_scope_offset =
-    1640;
+    1648;
 static constexpr dart::compiler::target::word
-    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word AOT_Thread_bool_false_offset =
     216;
 static constexpr dart::compiler::target::word AOT_Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_stub_offset = 264;
 static constexpr dart::compiler::target::word AOT_Thread_dart_stream_offset =
-    1656;
+    1688;
 static constexpr dart::compiler::target::word
     AOT_Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_truncate_round_supported_offset = 1648;
+    AOT_Thread_double_truncate_round_supported_offset = 1656;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_stub_offset =
@@ -8176,14 +8366,14 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_deoptimize_stub_offset = 448;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_abs_address_offset = 688;
+    AOT_Thread_double_abs_address_offset = 696;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_negate_address_offset = 680;
+    AOT_Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word AOT_Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     AOT_Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word
-    AOT_Thread_execution_state_offset = 1600;
+    AOT_Thread_execution_state_offset = 1608;
 static constexpr dart::compiler::target::word
     AOT_Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -8195,22 +8385,22 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_absolute_address_offset = 712;
+    AOT_Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_negate_address_offset = 704;
+    AOT_Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_not_address_offset = 696;
+    AOT_Thread_float_not_address_offset = 704;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_zerow_address_offset = 720;
+    AOT_Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word
-    AOT_Thread_global_object_pool_offset = 1576;
+    AOT_Thread_global_object_pool_offset = 1584;
 static constexpr dart::compiler::target::word
     AOT_Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word
-    AOT_Thread_exit_through_ffi_offset = 1632;
+    AOT_Thread_exit_through_ffi_offset = 1640;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_group_offset =
-    1664;
+    1696;
 static constexpr dart::compiler::target::word
     AOT_Thread_field_table_values_offset = 128;
 static constexpr dart::compiler::target::word
@@ -8228,7 +8418,7 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     AOT_Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -8253,17 +8443,17 @@
 static constexpr dart::compiler::target::word AOT_Thread_object_null_offset =
     200;
 static constexpr dart::compiler::target::word
-    AOT_Thread_predefined_symbols_address_offset = 664;
+    AOT_Thread_predefined_symbols_address_offset = 672;
 static constexpr dart::compiler::target::word AOT_Thread_resume_pc_offset =
-    1584;
+    1592;
 static constexpr dart::compiler::target::word
-    AOT_Thread_saved_shadow_call_stack_offset = 1592;
+    AOT_Thread_saved_shadow_call_stack_offset = 1600;
 static constexpr dart::compiler::target::word
-    AOT_Thread_safepoint_state_offset = 1608;
+    AOT_Thread_safepoint_state_offset = 1616;
 static constexpr dart::compiler::target::word
     AOT_Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    AOT_Thread_slow_type_test_entry_point_offset = 632;
+    AOT_Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word AOT_Thread_stack_limit_offset =
     56;
 static constexpr dart::compiler::target::word
@@ -8298,9 +8488,24 @@
     AOT_Thread_write_barrier_mask_offset = 64;
 static constexpr dart::compiler::target::word AOT_Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word AOT_Thread_callback_code_offset =
-    1616;
+    1624;
 static constexpr dart::compiler::target::word
-    AOT_Thread_callback_stack_return_offset = 1624;
+    AOT_Thread_callback_stack_return_offset = 1632;
+static constexpr dart::compiler::target::word AOT_Thread_random_offset = 1664;
+static constexpr dart::compiler::target::word
+    AOT_Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word AOT_Thread_tsan_utils_offset =
+    1672;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_function_offset = 0;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_buffer_offset = 8;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_pc_offset = 16;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_sp_offset = 24;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_fp_offset = 32;
 static constexpr dart::compiler::target::word
     AOT_TimelineStream_enabled_offset = 16;
 static constexpr dart::compiler::target::word AOT_TwoByteString_data_offset =
@@ -8374,9 +8579,9 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     AOT_Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488,
-        1496, 1504, 1512, 1520, -1,   -1,   -1,   -1,   1528, 1536, -1,
-        -1,   1544, 1552, 1560, -1,   -1,   -1,   -1,   -1,   -1};
+        1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488, 1496,
+        1504, 1512, 1520, 1528, -1,   -1,   -1,   -1,   1536, 1544, -1,
+        -1,   1552, 1560, 1568, -1,   -1,   -1,   -1,   -1,   -1};
 static constexpr dart::compiler::target::word AOT_AbstractType_InstanceSize =
     24;
 static constexpr dart::compiler::target::word AOT_ApiError_InstanceSize = 16;
@@ -8388,7 +8593,9 @@
 static constexpr dart::compiler::target::word AOT_ClosureData_InstanceSize = 40;
 static constexpr dart::compiler::target::word AOT_CodeSourceMap_HeaderSize = 16;
 static constexpr dart::compiler::target::word
-    AOT_CompressedStackMaps_HeaderSize = 16;
+    AOT_CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    AOT_CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word AOT_Context_header_size = 24;
 static constexpr dart::compiler::target::word AOT_Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word AOT_DynamicLibrary_InstanceSize =
@@ -8416,6 +8623,8 @@
     AOT_Instructions_UnalignedHeaderSize = 16;
 static constexpr dart::compiler::target::word
     AOT_InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word
+    AOT_InstructionsTable_InstanceSize = 48;
 static constexpr dart::compiler::target::word AOT_Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word
@@ -8472,7 +8681,7 @@
 static constexpr dart::compiler::target::word AOT_UnlinkedCall_InstanceSize =
     32;
 static constexpr dart::compiler::target::word AOT_UnwindError_InstanceSize = 24;
-static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word AOT_WeakProperty_InstanceSize =
     32;
 static constexpr dart::compiler::target::word
@@ -8503,10 +8712,6 @@
 static constexpr dart::compiler::target::word
     AOT_ExceptionHandlers_element_size = 12;
 static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_element_size = 4;
-static constexpr dart::compiler::target::word
     AOT_ObjectPool_elements_start_offset = 16;
 static constexpr dart::compiler::target::word AOT_ObjectPool_element_size = 8;
 static constexpr dart::compiler::target::word
@@ -8737,11 +8942,11 @@
 static constexpr dart::compiler::target::word
     AOT_SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    AOT_Thread_AllocateArray_entry_point_offset = 728;
+    AOT_Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_exception_offset = 1496;
+    AOT_Thread_active_exception_offset = 1504;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_stacktrace_offset = 1504;
+    AOT_Thread_active_stacktrace_offset = 1512;
 static constexpr dart::compiler::target::word
     AOT_Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -8767,24 +8972,24 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word AOT_Thread_api_top_scope_offset =
-    1576;
+    1584;
 static constexpr dart::compiler::target::word
-    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word AOT_Thread_bool_false_offset =
     216;
 static constexpr dart::compiler::target::word AOT_Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_stub_offset = 264;
 static constexpr dart::compiler::target::word AOT_Thread_dart_stream_offset =
-    1592;
+    1624;
 static constexpr dart::compiler::target::word
     AOT_Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_truncate_round_supported_offset = 1584;
+    AOT_Thread_double_truncate_round_supported_offset = 1592;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_stub_offset =
@@ -8794,14 +8999,14 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_deoptimize_stub_offset = 448;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_abs_address_offset = 688;
+    AOT_Thread_double_abs_address_offset = 696;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_negate_address_offset = 680;
+    AOT_Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word AOT_Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     AOT_Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word
-    AOT_Thread_execution_state_offset = 1536;
+    AOT_Thread_execution_state_offset = 1544;
 static constexpr dart::compiler::target::word
     AOT_Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -8813,22 +9018,22 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_absolute_address_offset = 712;
+    AOT_Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_negate_address_offset = 704;
+    AOT_Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_not_address_offset = 696;
+    AOT_Thread_float_not_address_offset = 704;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_zerow_address_offset = 720;
+    AOT_Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word
-    AOT_Thread_global_object_pool_offset = 1512;
+    AOT_Thread_global_object_pool_offset = 1520;
 static constexpr dart::compiler::target::word
     AOT_Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word
-    AOT_Thread_exit_through_ffi_offset = 1568;
+    AOT_Thread_exit_through_ffi_offset = 1576;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_group_offset =
-    1600;
+    1632;
 static constexpr dart::compiler::target::word
     AOT_Thread_field_table_values_offset = 128;
 static constexpr dart::compiler::target::word
@@ -8846,7 +9051,7 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     AOT_Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -8871,17 +9076,17 @@
 static constexpr dart::compiler::target::word AOT_Thread_object_null_offset =
     200;
 static constexpr dart::compiler::target::word
-    AOT_Thread_predefined_symbols_address_offset = 664;
+    AOT_Thread_predefined_symbols_address_offset = 672;
 static constexpr dart::compiler::target::word AOT_Thread_resume_pc_offset =
-    1520;
+    1528;
 static constexpr dart::compiler::target::word
-    AOT_Thread_saved_shadow_call_stack_offset = 1528;
+    AOT_Thread_saved_shadow_call_stack_offset = 1536;
 static constexpr dart::compiler::target::word
-    AOT_Thread_safepoint_state_offset = 1544;
+    AOT_Thread_safepoint_state_offset = 1552;
 static constexpr dart::compiler::target::word
     AOT_Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    AOT_Thread_slow_type_test_entry_point_offset = 632;
+    AOT_Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word AOT_Thread_stack_limit_offset =
     56;
 static constexpr dart::compiler::target::word
@@ -8916,9 +9121,24 @@
     AOT_Thread_write_barrier_mask_offset = 64;
 static constexpr dart::compiler::target::word AOT_Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word AOT_Thread_callback_code_offset =
-    1552;
+    1560;
 static constexpr dart::compiler::target::word
-    AOT_Thread_callback_stack_return_offset = 1560;
+    AOT_Thread_callback_stack_return_offset = 1568;
+static constexpr dart::compiler::target::word AOT_Thread_random_offset = 1600;
+static constexpr dart::compiler::target::word
+    AOT_Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word AOT_Thread_tsan_utils_offset =
+    1608;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_function_offset = 0;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_buffer_offset = 8;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_pc_offset = 16;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_sp_offset = 24;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_fp_offset = 32;
 static constexpr dart::compiler::target::word
     AOT_TimelineStream_enabled_offset = 16;
 static constexpr dart::compiler::target::word AOT_TwoByteString_data_offset =
@@ -8992,8 +9212,8 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     AOT_Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, -1,   -1,   1440, 1448,
-        1456, 1464, 1472, -1,   1480, 1488, -1,   -1};
+        1416, 1424, 1432, 1440, -1,   -1,   1448, 1456,
+        1464, 1472, 1480, -1,   1488, 1496, -1,   -1};
 static constexpr dart::compiler::target::word AOT_AbstractType_InstanceSize =
     24;
 static constexpr dart::compiler::target::word AOT_ApiError_InstanceSize = 16;
@@ -9005,7 +9225,9 @@
 static constexpr dart::compiler::target::word AOT_ClosureData_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_CodeSourceMap_HeaderSize = 16;
 static constexpr dart::compiler::target::word
-    AOT_CompressedStackMaps_HeaderSize = 16;
+    AOT_CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    AOT_CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word AOT_Context_header_size = 16;
 static constexpr dart::compiler::target::word AOT_Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word AOT_DynamicLibrary_InstanceSize =
@@ -9033,6 +9255,8 @@
     AOT_Instructions_UnalignedHeaderSize = 16;
 static constexpr dart::compiler::target::word
     AOT_InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word
+    AOT_InstructionsTable_InstanceSize = 48;
 static constexpr dart::compiler::target::word AOT_Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word
@@ -9089,7 +9313,7 @@
 static constexpr dart::compiler::target::word AOT_UnlinkedCall_InstanceSize =
     32;
 static constexpr dart::compiler::target::word AOT_UnwindError_InstanceSize = 16;
-static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word AOT_WeakProperty_InstanceSize =
     24;
 static constexpr dart::compiler::target::word
@@ -9120,10 +9344,6 @@
 static constexpr dart::compiler::target::word
     AOT_ExceptionHandlers_element_size = 12;
 static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_element_size = 4;
-static constexpr dart::compiler::target::word
     AOT_ObjectPool_elements_start_offset = 16;
 static constexpr dart::compiler::target::word AOT_ObjectPool_element_size = 8;
 static constexpr dart::compiler::target::word
@@ -9354,11 +9574,11 @@
 static constexpr dart::compiler::target::word
     AOT_SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    AOT_Thread_AllocateArray_entry_point_offset = 728;
+    AOT_Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_exception_offset = 1560;
+    AOT_Thread_active_exception_offset = 1568;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_stacktrace_offset = 1568;
+    AOT_Thread_active_stacktrace_offset = 1576;
 static constexpr dart::compiler::target::word
     AOT_Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -9384,24 +9604,24 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word AOT_Thread_api_top_scope_offset =
-    1640;
+    1648;
 static constexpr dart::compiler::target::word
-    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word AOT_Thread_bool_false_offset =
     216;
 static constexpr dart::compiler::target::word AOT_Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_stub_offset = 264;
 static constexpr dart::compiler::target::word AOT_Thread_dart_stream_offset =
-    1656;
+    1688;
 static constexpr dart::compiler::target::word
     AOT_Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_truncate_round_supported_offset = 1648;
+    AOT_Thread_double_truncate_round_supported_offset = 1656;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_stub_offset =
@@ -9411,14 +9631,14 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_deoptimize_stub_offset = 448;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_abs_address_offset = 688;
+    AOT_Thread_double_abs_address_offset = 696;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_negate_address_offset = 680;
+    AOT_Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word AOT_Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     AOT_Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word
-    AOT_Thread_execution_state_offset = 1600;
+    AOT_Thread_execution_state_offset = 1608;
 static constexpr dart::compiler::target::word
     AOT_Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -9430,22 +9650,22 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_absolute_address_offset = 712;
+    AOT_Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_negate_address_offset = 704;
+    AOT_Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_not_address_offset = 696;
+    AOT_Thread_float_not_address_offset = 704;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_zerow_address_offset = 720;
+    AOT_Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word
-    AOT_Thread_global_object_pool_offset = 1576;
+    AOT_Thread_global_object_pool_offset = 1584;
 static constexpr dart::compiler::target::word
     AOT_Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word
-    AOT_Thread_exit_through_ffi_offset = 1632;
+    AOT_Thread_exit_through_ffi_offset = 1640;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_group_offset =
-    1664;
+    1696;
 static constexpr dart::compiler::target::word
     AOT_Thread_field_table_values_offset = 128;
 static constexpr dart::compiler::target::word
@@ -9463,7 +9683,7 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     AOT_Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -9488,17 +9708,17 @@
 static constexpr dart::compiler::target::word AOT_Thread_object_null_offset =
     200;
 static constexpr dart::compiler::target::word
-    AOT_Thread_predefined_symbols_address_offset = 664;
+    AOT_Thread_predefined_symbols_address_offset = 672;
 static constexpr dart::compiler::target::word AOT_Thread_resume_pc_offset =
-    1584;
+    1592;
 static constexpr dart::compiler::target::word
-    AOT_Thread_saved_shadow_call_stack_offset = 1592;
+    AOT_Thread_saved_shadow_call_stack_offset = 1600;
 static constexpr dart::compiler::target::word
-    AOT_Thread_safepoint_state_offset = 1608;
+    AOT_Thread_safepoint_state_offset = 1616;
 static constexpr dart::compiler::target::word
     AOT_Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    AOT_Thread_slow_type_test_entry_point_offset = 632;
+    AOT_Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word AOT_Thread_stack_limit_offset =
     56;
 static constexpr dart::compiler::target::word
@@ -9533,9 +9753,24 @@
     AOT_Thread_write_barrier_mask_offset = 64;
 static constexpr dart::compiler::target::word AOT_Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word AOT_Thread_callback_code_offset =
-    1616;
+    1624;
 static constexpr dart::compiler::target::word
-    AOT_Thread_callback_stack_return_offset = 1624;
+    AOT_Thread_callback_stack_return_offset = 1632;
+static constexpr dart::compiler::target::word AOT_Thread_random_offset = 1664;
+static constexpr dart::compiler::target::word
+    AOT_Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word AOT_Thread_tsan_utils_offset =
+    1672;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_function_offset = 0;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_buffer_offset = 8;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_pc_offset = 16;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_sp_offset = 24;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_fp_offset = 32;
 static constexpr dart::compiler::target::word
     AOT_TimelineStream_enabled_offset = 16;
 static constexpr dart::compiler::target::word AOT_TwoByteString_data_offset =
@@ -9609,9 +9844,9 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     AOT_Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488,
-        1496, 1504, 1512, 1520, -1,   -1,   -1,   -1,   1528, 1536, -1,
-        -1,   1544, 1552, 1560, -1,   -1,   -1,   -1,   -1,   -1};
+        1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488, 1496,
+        1504, 1512, 1520, 1528, -1,   -1,   -1,   -1,   1536, 1544, -1,
+        -1,   1552, 1560, 1568, -1,   -1,   -1,   -1,   -1,   -1};
 static constexpr dart::compiler::target::word AOT_AbstractType_InstanceSize =
     24;
 static constexpr dart::compiler::target::word AOT_ApiError_InstanceSize = 16;
@@ -9623,7 +9858,9 @@
 static constexpr dart::compiler::target::word AOT_ClosureData_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_CodeSourceMap_HeaderSize = 16;
 static constexpr dart::compiler::target::word
-    AOT_CompressedStackMaps_HeaderSize = 16;
+    AOT_CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    AOT_CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word AOT_Context_header_size = 16;
 static constexpr dart::compiler::target::word AOT_Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word AOT_DynamicLibrary_InstanceSize =
@@ -9651,6 +9888,8 @@
     AOT_Instructions_UnalignedHeaderSize = 16;
 static constexpr dart::compiler::target::word
     AOT_InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word
+    AOT_InstructionsTable_InstanceSize = 48;
 static constexpr dart::compiler::target::word AOT_Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word
@@ -9707,7 +9946,7 @@
 static constexpr dart::compiler::target::word AOT_UnlinkedCall_InstanceSize =
     32;
 static constexpr dart::compiler::target::word AOT_UnwindError_InstanceSize = 16;
-static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word AOT_WeakProperty_InstanceSize =
     24;
 static constexpr dart::compiler::target::word
@@ -9737,10 +9976,6 @@
 static constexpr dart::compiler::target::word
     AOT_ExceptionHandlers_element_size = 12;
 static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_elements_start_offset = 20;
-static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_element_size = 4;
-static constexpr dart::compiler::target::word
     AOT_ObjectPool_elements_start_offset = 8;
 static constexpr dart::compiler::target::word AOT_ObjectPool_element_size = 4;
 static constexpr dart::compiler::target::word
@@ -9967,11 +10202,11 @@
 static constexpr dart::compiler::target::word
     AOT_SubtypeTestCache_cache_offset = 4;
 static constexpr dart::compiler::target::word
-    AOT_Thread_AllocateArray_entry_point_offset = 376;
+    AOT_Thread_AllocateArray_entry_point_offset = 380;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_exception_offset = 748;
+    AOT_Thread_active_exception_offset = 752;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_stacktrace_offset = 752;
+    AOT_Thread_active_stacktrace_offset = 756;
 static constexpr dart::compiler::target::word
     AOT_Thread_array_write_barrier_code_offset = 128;
 static constexpr dart::compiler::target::word
@@ -9997,24 +10232,24 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_allocate_object_slow_stub_offset = 204;
 static constexpr dart::compiler::target::word AOT_Thread_api_top_scope_offset =
-    788;
+    792;
 static constexpr dart::compiler::target::word
-    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 340;
+    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 344;
 static constexpr dart::compiler::target::word AOT_Thread_bool_false_offset =
     120;
 static constexpr dart::compiler::target::word AOT_Thread_bool_true_offset = 116;
 static constexpr dart::compiler::target::word
-    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 332;
+    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 336;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_entry_point_offset = 276;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_stub_offset = 144;
 static constexpr dart::compiler::target::word AOT_Thread_dart_stream_offset =
-    800;
+    816;
 static constexpr dart::compiler::target::word
     AOT_Thread_dispatch_table_array_offset = 44;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_truncate_round_supported_offset = 792;
+    AOT_Thread_double_truncate_round_supported_offset = 796;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_entry_offset =
     316;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_stub_offset =
@@ -10024,14 +10259,14 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_deoptimize_stub_offset = 236;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_abs_address_offset = 356;
+    AOT_Thread_double_abs_address_offset = 360;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_negate_address_offset = 352;
+    AOT_Thread_double_negate_address_offset = 356;
 static constexpr dart::compiler::target::word AOT_Thread_end_offset = 52;
 static constexpr dart::compiler::target::word
     AOT_Thread_enter_safepoint_stub_offset = 256;
 static constexpr dart::compiler::target::word
-    AOT_Thread_execution_state_offset = 768;
+    AOT_Thread_execution_state_offset = 772;
 static constexpr dart::compiler::target::word
     AOT_Thread_exit_safepoint_stub_offset = 260;
 static constexpr dart::compiler::target::word
@@ -10043,22 +10278,22 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_fix_callers_target_code_offset = 132;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_absolute_address_offset = 368;
+    AOT_Thread_float_absolute_address_offset = 372;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_negate_address_offset = 364;
+    AOT_Thread_float_negate_address_offset = 368;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_not_address_offset = 360;
+    AOT_Thread_float_not_address_offset = 364;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_zerow_address_offset = 372;
+    AOT_Thread_float_zerow_address_offset = 376;
 static constexpr dart::compiler::target::word
-    AOT_Thread_global_object_pool_offset = 756;
+    AOT_Thread_global_object_pool_offset = 760;
 static constexpr dart::compiler::target::word
     AOT_Thread_invoke_dart_code_stub_offset = 140;
 static constexpr dart::compiler::target::word
-    AOT_Thread_exit_through_ffi_offset = 784;
+    AOT_Thread_exit_through_ffi_offset = 788;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_offset = 40;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_group_offset =
-    804;
+    820;
 static constexpr dart::compiler::target::word
     AOT_Thread_field_table_values_offset = 64;
 static constexpr dart::compiler::target::word
@@ -10076,7 +10311,7 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_switchable_call_miss_stub_offset = 216;
 static constexpr dart::compiler::target::word
-    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 336;
+    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 340;
 static constexpr dart::compiler::target::word
     AOT_Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 152;
 static constexpr dart::compiler::target::word
@@ -10101,16 +10336,16 @@
 static constexpr dart::compiler::target::word AOT_Thread_object_null_offset =
     112;
 static constexpr dart::compiler::target::word
-    AOT_Thread_predefined_symbols_address_offset = 344;
-static constexpr dart::compiler::target::word AOT_Thread_resume_pc_offset = 760;
+    AOT_Thread_predefined_symbols_address_offset = 348;
+static constexpr dart::compiler::target::word AOT_Thread_resume_pc_offset = 764;
 static constexpr dart::compiler::target::word
-    AOT_Thread_saved_shadow_call_stack_offset = 764;
+    AOT_Thread_saved_shadow_call_stack_offset = 768;
 static constexpr dart::compiler::target::word
-    AOT_Thread_safepoint_state_offset = 772;
+    AOT_Thread_safepoint_state_offset = 776;
 static constexpr dart::compiler::target::word
     AOT_Thread_slow_type_test_stub_offset = 248;
 static constexpr dart::compiler::target::word
-    AOT_Thread_slow_type_test_entry_point_offset = 328;
+    AOT_Thread_slow_type_test_entry_point_offset = 332;
 static constexpr dart::compiler::target::word AOT_Thread_stack_limit_offset =
     28;
 static constexpr dart::compiler::target::word
@@ -10145,9 +10380,24 @@
     AOT_Thread_write_barrier_mask_offset = 32;
 static constexpr dart::compiler::target::word AOT_Thread_heap_base_offset = 36;
 static constexpr dart::compiler::target::word AOT_Thread_callback_code_offset =
-    776;
+    780;
 static constexpr dart::compiler::target::word
-    AOT_Thread_callback_stack_return_offset = 780;
+    AOT_Thread_callback_stack_return_offset = 784;
+static constexpr dart::compiler::target::word AOT_Thread_random_offset = 800;
+static constexpr dart::compiler::target::word
+    AOT_Thread_jump_to_frame_entry_point_offset = 328;
+static constexpr dart::compiler::target::word AOT_Thread_tsan_utils_offset =
+    808;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_function_offset = 0;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_buffer_offset = 4;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_pc_offset = 8;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_sp_offset = 12;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_fp_offset = 16;
 static constexpr dart::compiler::target::word
     AOT_TimelineStream_enabled_offset = 8;
 static constexpr dart::compiler::target::word AOT_TwoByteString_data_offset =
@@ -10220,7 +10470,7 @@
     4, 12, 8, 16};
 static constexpr dart::compiler::target::word
     AOT_Thread_write_barrier_wrappers_thread_offset[] = {
-        716, 720, 724, 728, 732, -1, 736, -1, 740, 744, -1, -1, -1, -1, -1, -1};
+        720, 724, 728, 732, 736, -1, 740, -1, 744, 748, -1, -1, -1, -1, -1, -1};
 static constexpr dart::compiler::target::word AOT_AbstractType_InstanceSize =
     12;
 static constexpr dart::compiler::target::word AOT_ApiError_InstanceSize = 8;
@@ -10232,7 +10482,9 @@
 static constexpr dart::compiler::target::word AOT_ClosureData_InstanceSize = 20;
 static constexpr dart::compiler::target::word AOT_CodeSourceMap_HeaderSize = 8;
 static constexpr dart::compiler::target::word
-    AOT_CompressedStackMaps_HeaderSize = 8;
+    AOT_CompressedStackMaps_ObjectHeaderSize = 4;
+static constexpr dart::compiler::target::word
+    AOT_CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word AOT_Context_header_size = 12;
 static constexpr dart::compiler::target::word AOT_Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word AOT_DynamicLibrary_InstanceSize =
@@ -10260,6 +10512,8 @@
     AOT_Instructions_UnalignedHeaderSize = 8;
 static constexpr dart::compiler::target::word
     AOT_InstructionsSection_UnalignedHeaderSize = 20;
+static constexpr dart::compiler::target::word
+    AOT_InstructionsTable_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_Integer_InstanceSize = 4;
 static constexpr dart::compiler::target::word
@@ -10316,7 +10570,7 @@
 static constexpr dart::compiler::target::word AOT_UnlinkedCall_InstanceSize =
     16;
 static constexpr dart::compiler::target::word AOT_UnwindError_InstanceSize = 12;
-static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 12;
+static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 16;
 static constexpr dart::compiler::target::word AOT_WeakProperty_InstanceSize =
     16;
 static constexpr dart::compiler::target::word
@@ -10344,10 +10598,6 @@
 static constexpr dart::compiler::target::word
     AOT_ExceptionHandlers_element_size = 12;
 static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_element_size = 4;
-static constexpr dart::compiler::target::word
     AOT_ObjectPool_elements_start_offset = 16;
 static constexpr dart::compiler::target::word AOT_ObjectPool_element_size = 8;
 static constexpr dart::compiler::target::word
@@ -10575,11 +10825,11 @@
 static constexpr dart::compiler::target::word
     AOT_SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    AOT_Thread_AllocateArray_entry_point_offset = 728;
+    AOT_Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_exception_offset = 1496;
+    AOT_Thread_active_exception_offset = 1504;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_stacktrace_offset = 1504;
+    AOT_Thread_active_stacktrace_offset = 1512;
 static constexpr dart::compiler::target::word
     AOT_Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -10605,24 +10855,24 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word AOT_Thread_api_top_scope_offset =
-    1576;
+    1584;
 static constexpr dart::compiler::target::word
-    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word AOT_Thread_bool_false_offset =
     216;
 static constexpr dart::compiler::target::word AOT_Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_stub_offset = 264;
 static constexpr dart::compiler::target::word AOT_Thread_dart_stream_offset =
-    1592;
+    1624;
 static constexpr dart::compiler::target::word
     AOT_Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_truncate_round_supported_offset = 1584;
+    AOT_Thread_double_truncate_round_supported_offset = 1592;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_stub_offset =
@@ -10632,14 +10882,14 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_deoptimize_stub_offset = 448;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_abs_address_offset = 688;
+    AOT_Thread_double_abs_address_offset = 696;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_negate_address_offset = 680;
+    AOT_Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word AOT_Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     AOT_Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word
-    AOT_Thread_execution_state_offset = 1536;
+    AOT_Thread_execution_state_offset = 1544;
 static constexpr dart::compiler::target::word
     AOT_Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -10651,22 +10901,22 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_absolute_address_offset = 712;
+    AOT_Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_negate_address_offset = 704;
+    AOT_Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_not_address_offset = 696;
+    AOT_Thread_float_not_address_offset = 704;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_zerow_address_offset = 720;
+    AOT_Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word
-    AOT_Thread_global_object_pool_offset = 1512;
+    AOT_Thread_global_object_pool_offset = 1520;
 static constexpr dart::compiler::target::word
     AOT_Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word
-    AOT_Thread_exit_through_ffi_offset = 1568;
+    AOT_Thread_exit_through_ffi_offset = 1576;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_group_offset =
-    1600;
+    1632;
 static constexpr dart::compiler::target::word
     AOT_Thread_field_table_values_offset = 128;
 static constexpr dart::compiler::target::word
@@ -10684,7 +10934,7 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     AOT_Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -10709,17 +10959,17 @@
 static constexpr dart::compiler::target::word AOT_Thread_object_null_offset =
     200;
 static constexpr dart::compiler::target::word
-    AOT_Thread_predefined_symbols_address_offset = 664;
+    AOT_Thread_predefined_symbols_address_offset = 672;
 static constexpr dart::compiler::target::word AOT_Thread_resume_pc_offset =
-    1520;
+    1528;
 static constexpr dart::compiler::target::word
-    AOT_Thread_saved_shadow_call_stack_offset = 1528;
+    AOT_Thread_saved_shadow_call_stack_offset = 1536;
 static constexpr dart::compiler::target::word
-    AOT_Thread_safepoint_state_offset = 1544;
+    AOT_Thread_safepoint_state_offset = 1552;
 static constexpr dart::compiler::target::word
     AOT_Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    AOT_Thread_slow_type_test_entry_point_offset = 632;
+    AOT_Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word AOT_Thread_stack_limit_offset =
     56;
 static constexpr dart::compiler::target::word
@@ -10754,9 +11004,24 @@
     AOT_Thread_write_barrier_mask_offset = 64;
 static constexpr dart::compiler::target::word AOT_Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word AOT_Thread_callback_code_offset =
-    1552;
+    1560;
 static constexpr dart::compiler::target::word
-    AOT_Thread_callback_stack_return_offset = 1560;
+    AOT_Thread_callback_stack_return_offset = 1568;
+static constexpr dart::compiler::target::word AOT_Thread_random_offset = 1600;
+static constexpr dart::compiler::target::word
+    AOT_Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word AOT_Thread_tsan_utils_offset =
+    1608;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_function_offset = 0;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_buffer_offset = 8;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_pc_offset = 16;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_sp_offset = 24;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_fp_offset = 32;
 static constexpr dart::compiler::target::word
     AOT_TimelineStream_enabled_offset = 16;
 static constexpr dart::compiler::target::word AOT_TwoByteString_data_offset =
@@ -10830,8 +11095,8 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     AOT_Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, -1,   -1,   1440, 1448,
-        1456, 1464, 1472, -1,   1480, 1488, -1,   -1};
+        1416, 1424, 1432, 1440, -1,   -1,   1448, 1456,
+        1464, 1472, 1480, -1,   1488, 1496, -1,   -1};
 static constexpr dart::compiler::target::word AOT_AbstractType_InstanceSize =
     24;
 static constexpr dart::compiler::target::word AOT_ApiError_InstanceSize = 16;
@@ -10843,7 +11108,9 @@
 static constexpr dart::compiler::target::word AOT_ClosureData_InstanceSize = 40;
 static constexpr dart::compiler::target::word AOT_CodeSourceMap_HeaderSize = 16;
 static constexpr dart::compiler::target::word
-    AOT_CompressedStackMaps_HeaderSize = 16;
+    AOT_CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    AOT_CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word AOT_Context_header_size = 24;
 static constexpr dart::compiler::target::word AOT_Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word AOT_DynamicLibrary_InstanceSize =
@@ -10871,6 +11138,8 @@
     AOT_Instructions_UnalignedHeaderSize = 16;
 static constexpr dart::compiler::target::word
     AOT_InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word
+    AOT_InstructionsTable_InstanceSize = 48;
 static constexpr dart::compiler::target::word AOT_Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word
@@ -10927,7 +11196,7 @@
 static constexpr dart::compiler::target::word AOT_UnlinkedCall_InstanceSize =
     32;
 static constexpr dart::compiler::target::word AOT_UnwindError_InstanceSize = 24;
-static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word AOT_WeakProperty_InstanceSize =
     32;
 static constexpr dart::compiler::target::word
@@ -10958,10 +11227,6 @@
 static constexpr dart::compiler::target::word
     AOT_ExceptionHandlers_element_size = 12;
 static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_element_size = 4;
-static constexpr dart::compiler::target::word
     AOT_ObjectPool_elements_start_offset = 16;
 static constexpr dart::compiler::target::word AOT_ObjectPool_element_size = 8;
 static constexpr dart::compiler::target::word
@@ -11189,11 +11454,11 @@
 static constexpr dart::compiler::target::word
     AOT_SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    AOT_Thread_AllocateArray_entry_point_offset = 728;
+    AOT_Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_exception_offset = 1560;
+    AOT_Thread_active_exception_offset = 1568;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_stacktrace_offset = 1568;
+    AOT_Thread_active_stacktrace_offset = 1576;
 static constexpr dart::compiler::target::word
     AOT_Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -11219,24 +11484,24 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word AOT_Thread_api_top_scope_offset =
-    1640;
+    1648;
 static constexpr dart::compiler::target::word
-    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word AOT_Thread_bool_false_offset =
     216;
 static constexpr dart::compiler::target::word AOT_Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_stub_offset = 264;
 static constexpr dart::compiler::target::word AOT_Thread_dart_stream_offset =
-    1656;
+    1688;
 static constexpr dart::compiler::target::word
     AOT_Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_truncate_round_supported_offset = 1648;
+    AOT_Thread_double_truncate_round_supported_offset = 1656;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_stub_offset =
@@ -11246,14 +11511,14 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_deoptimize_stub_offset = 448;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_abs_address_offset = 688;
+    AOT_Thread_double_abs_address_offset = 696;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_negate_address_offset = 680;
+    AOT_Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word AOT_Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     AOT_Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word
-    AOT_Thread_execution_state_offset = 1600;
+    AOT_Thread_execution_state_offset = 1608;
 static constexpr dart::compiler::target::word
     AOT_Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -11265,22 +11530,22 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_absolute_address_offset = 712;
+    AOT_Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_negate_address_offset = 704;
+    AOT_Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_not_address_offset = 696;
+    AOT_Thread_float_not_address_offset = 704;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_zerow_address_offset = 720;
+    AOT_Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word
-    AOT_Thread_global_object_pool_offset = 1576;
+    AOT_Thread_global_object_pool_offset = 1584;
 static constexpr dart::compiler::target::word
     AOT_Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word
-    AOT_Thread_exit_through_ffi_offset = 1632;
+    AOT_Thread_exit_through_ffi_offset = 1640;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_group_offset =
-    1664;
+    1696;
 static constexpr dart::compiler::target::word
     AOT_Thread_field_table_values_offset = 128;
 static constexpr dart::compiler::target::word
@@ -11298,7 +11563,7 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     AOT_Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -11323,17 +11588,17 @@
 static constexpr dart::compiler::target::word AOT_Thread_object_null_offset =
     200;
 static constexpr dart::compiler::target::word
-    AOT_Thread_predefined_symbols_address_offset = 664;
+    AOT_Thread_predefined_symbols_address_offset = 672;
 static constexpr dart::compiler::target::word AOT_Thread_resume_pc_offset =
-    1584;
+    1592;
 static constexpr dart::compiler::target::word
-    AOT_Thread_saved_shadow_call_stack_offset = 1592;
+    AOT_Thread_saved_shadow_call_stack_offset = 1600;
 static constexpr dart::compiler::target::word
-    AOT_Thread_safepoint_state_offset = 1608;
+    AOT_Thread_safepoint_state_offset = 1616;
 static constexpr dart::compiler::target::word
     AOT_Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    AOT_Thread_slow_type_test_entry_point_offset = 632;
+    AOT_Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word AOT_Thread_stack_limit_offset =
     56;
 static constexpr dart::compiler::target::word
@@ -11368,9 +11633,24 @@
     AOT_Thread_write_barrier_mask_offset = 64;
 static constexpr dart::compiler::target::word AOT_Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word AOT_Thread_callback_code_offset =
-    1616;
+    1624;
 static constexpr dart::compiler::target::word
-    AOT_Thread_callback_stack_return_offset = 1624;
+    AOT_Thread_callback_stack_return_offset = 1632;
+static constexpr dart::compiler::target::word AOT_Thread_random_offset = 1664;
+static constexpr dart::compiler::target::word
+    AOT_Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word AOT_Thread_tsan_utils_offset =
+    1672;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_function_offset = 0;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_buffer_offset = 8;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_pc_offset = 16;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_sp_offset = 24;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_fp_offset = 32;
 static constexpr dart::compiler::target::word
     AOT_TimelineStream_enabled_offset = 16;
 static constexpr dart::compiler::target::word AOT_TwoByteString_data_offset =
@@ -11444,9 +11724,9 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     AOT_Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488,
-        1496, 1504, 1512, 1520, -1,   -1,   -1,   -1,   1528, 1536, -1,
-        -1,   1544, 1552, 1560, -1,   -1,   -1,   -1,   -1,   -1};
+        1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488, 1496,
+        1504, 1512, 1520, 1528, -1,   -1,   -1,   -1,   1536, 1544, -1,
+        -1,   1552, 1560, 1568, -1,   -1,   -1,   -1,   -1,   -1};
 static constexpr dart::compiler::target::word AOT_AbstractType_InstanceSize =
     24;
 static constexpr dart::compiler::target::word AOT_ApiError_InstanceSize = 16;
@@ -11458,7 +11738,9 @@
 static constexpr dart::compiler::target::word AOT_ClosureData_InstanceSize = 40;
 static constexpr dart::compiler::target::word AOT_CodeSourceMap_HeaderSize = 16;
 static constexpr dart::compiler::target::word
-    AOT_CompressedStackMaps_HeaderSize = 16;
+    AOT_CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    AOT_CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word AOT_Context_header_size = 24;
 static constexpr dart::compiler::target::word AOT_Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word AOT_DynamicLibrary_InstanceSize =
@@ -11486,6 +11768,8 @@
     AOT_Instructions_UnalignedHeaderSize = 16;
 static constexpr dart::compiler::target::word
     AOT_InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word
+    AOT_InstructionsTable_InstanceSize = 48;
 static constexpr dart::compiler::target::word AOT_Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word
@@ -11542,7 +11826,7 @@
 static constexpr dart::compiler::target::word AOT_UnlinkedCall_InstanceSize =
     32;
 static constexpr dart::compiler::target::word AOT_UnwindError_InstanceSize = 24;
-static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word AOT_WeakProperty_InstanceSize =
     32;
 static constexpr dart::compiler::target::word
@@ -11570,10 +11854,6 @@
 static constexpr dart::compiler::target::word
     AOT_ExceptionHandlers_element_size = 12;
 static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_element_size = 4;
-static constexpr dart::compiler::target::word
     AOT_ObjectPool_elements_start_offset = 16;
 static constexpr dart::compiler::target::word AOT_ObjectPool_element_size = 8;
 static constexpr dart::compiler::target::word
@@ -11800,11 +12080,11 @@
 static constexpr dart::compiler::target::word
     AOT_SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    AOT_Thread_AllocateArray_entry_point_offset = 728;
+    AOT_Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_exception_offset = 1496;
+    AOT_Thread_active_exception_offset = 1504;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_stacktrace_offset = 1504;
+    AOT_Thread_active_stacktrace_offset = 1512;
 static constexpr dart::compiler::target::word
     AOT_Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -11830,24 +12110,24 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word AOT_Thread_api_top_scope_offset =
-    1576;
+    1584;
 static constexpr dart::compiler::target::word
-    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word AOT_Thread_bool_false_offset =
     216;
 static constexpr dart::compiler::target::word AOT_Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_stub_offset = 264;
 static constexpr dart::compiler::target::word AOT_Thread_dart_stream_offset =
-    1592;
+    1624;
 static constexpr dart::compiler::target::word
     AOT_Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_truncate_round_supported_offset = 1584;
+    AOT_Thread_double_truncate_round_supported_offset = 1592;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_stub_offset =
@@ -11857,14 +12137,14 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_deoptimize_stub_offset = 448;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_abs_address_offset = 688;
+    AOT_Thread_double_abs_address_offset = 696;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_negate_address_offset = 680;
+    AOT_Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word AOT_Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     AOT_Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word
-    AOT_Thread_execution_state_offset = 1536;
+    AOT_Thread_execution_state_offset = 1544;
 static constexpr dart::compiler::target::word
     AOT_Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -11876,22 +12156,22 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_absolute_address_offset = 712;
+    AOT_Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_negate_address_offset = 704;
+    AOT_Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_not_address_offset = 696;
+    AOT_Thread_float_not_address_offset = 704;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_zerow_address_offset = 720;
+    AOT_Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word
-    AOT_Thread_global_object_pool_offset = 1512;
+    AOT_Thread_global_object_pool_offset = 1520;
 static constexpr dart::compiler::target::word
     AOT_Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word
-    AOT_Thread_exit_through_ffi_offset = 1568;
+    AOT_Thread_exit_through_ffi_offset = 1576;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_group_offset =
-    1600;
+    1632;
 static constexpr dart::compiler::target::word
     AOT_Thread_field_table_values_offset = 128;
 static constexpr dart::compiler::target::word
@@ -11909,7 +12189,7 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     AOT_Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -11934,17 +12214,17 @@
 static constexpr dart::compiler::target::word AOT_Thread_object_null_offset =
     200;
 static constexpr dart::compiler::target::word
-    AOT_Thread_predefined_symbols_address_offset = 664;
+    AOT_Thread_predefined_symbols_address_offset = 672;
 static constexpr dart::compiler::target::word AOT_Thread_resume_pc_offset =
-    1520;
+    1528;
 static constexpr dart::compiler::target::word
-    AOT_Thread_saved_shadow_call_stack_offset = 1528;
+    AOT_Thread_saved_shadow_call_stack_offset = 1536;
 static constexpr dart::compiler::target::word
-    AOT_Thread_safepoint_state_offset = 1544;
+    AOT_Thread_safepoint_state_offset = 1552;
 static constexpr dart::compiler::target::word
     AOT_Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    AOT_Thread_slow_type_test_entry_point_offset = 632;
+    AOT_Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word AOT_Thread_stack_limit_offset =
     56;
 static constexpr dart::compiler::target::word
@@ -11979,9 +12259,24 @@
     AOT_Thread_write_barrier_mask_offset = 64;
 static constexpr dart::compiler::target::word AOT_Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word AOT_Thread_callback_code_offset =
-    1552;
+    1560;
 static constexpr dart::compiler::target::word
-    AOT_Thread_callback_stack_return_offset = 1560;
+    AOT_Thread_callback_stack_return_offset = 1568;
+static constexpr dart::compiler::target::word AOT_Thread_random_offset = 1600;
+static constexpr dart::compiler::target::word
+    AOT_Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word AOT_Thread_tsan_utils_offset =
+    1608;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_function_offset = 0;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_buffer_offset = 8;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_pc_offset = 16;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_sp_offset = 24;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_fp_offset = 32;
 static constexpr dart::compiler::target::word
     AOT_TimelineStream_enabled_offset = 16;
 static constexpr dart::compiler::target::word AOT_TwoByteString_data_offset =
@@ -12055,8 +12350,8 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     AOT_Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, -1,   -1,   1440, 1448,
-        1456, 1464, 1472, -1,   1480, 1488, -1,   -1};
+        1416, 1424, 1432, 1440, -1,   -1,   1448, 1456,
+        1464, 1472, 1480, -1,   1488, 1496, -1,   -1};
 static constexpr dart::compiler::target::word AOT_AbstractType_InstanceSize =
     24;
 static constexpr dart::compiler::target::word AOT_ApiError_InstanceSize = 16;
@@ -12068,7 +12363,9 @@
 static constexpr dart::compiler::target::word AOT_ClosureData_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_CodeSourceMap_HeaderSize = 16;
 static constexpr dart::compiler::target::word
-    AOT_CompressedStackMaps_HeaderSize = 16;
+    AOT_CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    AOT_CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word AOT_Context_header_size = 16;
 static constexpr dart::compiler::target::word AOT_Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word AOT_DynamicLibrary_InstanceSize =
@@ -12096,6 +12393,8 @@
     AOT_Instructions_UnalignedHeaderSize = 16;
 static constexpr dart::compiler::target::word
     AOT_InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word
+    AOT_InstructionsTable_InstanceSize = 48;
 static constexpr dart::compiler::target::word AOT_Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word
@@ -12152,7 +12451,7 @@
 static constexpr dart::compiler::target::word AOT_UnlinkedCall_InstanceSize =
     32;
 static constexpr dart::compiler::target::word AOT_UnwindError_InstanceSize = 16;
-static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word AOT_WeakProperty_InstanceSize =
     24;
 static constexpr dart::compiler::target::word
@@ -12180,10 +12479,6 @@
 static constexpr dart::compiler::target::word
     AOT_ExceptionHandlers_element_size = 12;
 static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_elements_start_offset = 40;
-static constexpr dart::compiler::target::word
-    AOT_InstructionsTable_element_size = 4;
-static constexpr dart::compiler::target::word
     AOT_ObjectPool_elements_start_offset = 16;
 static constexpr dart::compiler::target::word AOT_ObjectPool_element_size = 8;
 static constexpr dart::compiler::target::word
@@ -12410,11 +12705,11 @@
 static constexpr dart::compiler::target::word
     AOT_SubtypeTestCache_cache_offset = 8;
 static constexpr dart::compiler::target::word
-    AOT_Thread_AllocateArray_entry_point_offset = 728;
+    AOT_Thread_AllocateArray_entry_point_offset = 736;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_exception_offset = 1560;
+    AOT_Thread_active_exception_offset = 1568;
 static constexpr dart::compiler::target::word
-    AOT_Thread_active_stacktrace_offset = 1568;
+    AOT_Thread_active_stacktrace_offset = 1576;
 static constexpr dart::compiler::target::word
     AOT_Thread_array_write_barrier_code_offset = 232;
 static constexpr dart::compiler::target::word
@@ -12440,24 +12735,24 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_allocate_object_slow_stub_offset = 384;
 static constexpr dart::compiler::target::word AOT_Thread_api_top_scope_offset =
-    1640;
+    1648;
 static constexpr dart::compiler::target::word
-    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 656;
+    AOT_Thread_auto_scope_native_wrapper_entry_point_offset = 664;
 static constexpr dart::compiler::target::word AOT_Thread_bool_false_offset =
     216;
 static constexpr dart::compiler::target::word AOT_Thread_bool_true_offset = 208;
 static constexpr dart::compiler::target::word
-    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 640;
+    AOT_Thread_bootstrap_native_wrapper_entry_point_offset = 648;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_entry_point_offset = 528;
 static constexpr dart::compiler::target::word
     AOT_Thread_call_to_runtime_stub_offset = 264;
 static constexpr dart::compiler::target::word AOT_Thread_dart_stream_offset =
-    1656;
+    1688;
 static constexpr dart::compiler::target::word
     AOT_Thread_dispatch_table_array_offset = 88;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_truncate_round_supported_offset = 1648;
+    AOT_Thread_double_truncate_round_supported_offset = 1656;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_entry_offset =
     608;
 static constexpr dart::compiler::target::word AOT_Thread_optimize_stub_offset =
@@ -12467,14 +12762,14 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_deoptimize_stub_offset = 448;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_abs_address_offset = 688;
+    AOT_Thread_double_abs_address_offset = 696;
 static constexpr dart::compiler::target::word
-    AOT_Thread_double_negate_address_offset = 680;
+    AOT_Thread_double_negate_address_offset = 688;
 static constexpr dart::compiler::target::word AOT_Thread_end_offset = 104;
 static constexpr dart::compiler::target::word
     AOT_Thread_enter_safepoint_stub_offset = 488;
 static constexpr dart::compiler::target::word
-    AOT_Thread_execution_state_offset = 1600;
+    AOT_Thread_execution_state_offset = 1608;
 static constexpr dart::compiler::target::word
     AOT_Thread_exit_safepoint_stub_offset = 496;
 static constexpr dart::compiler::target::word
@@ -12486,22 +12781,22 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_fix_callers_target_code_offset = 240;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_absolute_address_offset = 712;
+    AOT_Thread_float_absolute_address_offset = 720;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_negate_address_offset = 704;
+    AOT_Thread_float_negate_address_offset = 712;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_not_address_offset = 696;
+    AOT_Thread_float_not_address_offset = 704;
 static constexpr dart::compiler::target::word
-    AOT_Thread_float_zerow_address_offset = 720;
+    AOT_Thread_float_zerow_address_offset = 728;
 static constexpr dart::compiler::target::word
-    AOT_Thread_global_object_pool_offset = 1576;
+    AOT_Thread_global_object_pool_offset = 1584;
 static constexpr dart::compiler::target::word
     AOT_Thread_invoke_dart_code_stub_offset = 256;
 static constexpr dart::compiler::target::word
-    AOT_Thread_exit_through_ffi_offset = 1632;
+    AOT_Thread_exit_through_ffi_offset = 1640;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_offset = 80;
 static constexpr dart::compiler::target::word AOT_Thread_isolate_group_offset =
-    1664;
+    1696;
 static constexpr dart::compiler::target::word
     AOT_Thread_field_table_values_offset = 128;
 static constexpr dart::compiler::target::word
@@ -12519,7 +12814,7 @@
 static constexpr dart::compiler::target::word
     AOT_Thread_switchable_call_miss_stub_offset = 408;
 static constexpr dart::compiler::target::word
-    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 648;
+    AOT_Thread_no_scope_native_wrapper_entry_point_offset = 656;
 static constexpr dart::compiler::target::word
     AOT_Thread_late_initialization_error_shared_with_fpu_regs_stub_offset = 280;
 static constexpr dart::compiler::target::word
@@ -12544,17 +12839,17 @@
 static constexpr dart::compiler::target::word AOT_Thread_object_null_offset =
     200;
 static constexpr dart::compiler::target::word
-    AOT_Thread_predefined_symbols_address_offset = 664;
+    AOT_Thread_predefined_symbols_address_offset = 672;
 static constexpr dart::compiler::target::word AOT_Thread_resume_pc_offset =
-    1584;
+    1592;
 static constexpr dart::compiler::target::word
-    AOT_Thread_saved_shadow_call_stack_offset = 1592;
+    AOT_Thread_saved_shadow_call_stack_offset = 1600;
 static constexpr dart::compiler::target::word
-    AOT_Thread_safepoint_state_offset = 1608;
+    AOT_Thread_safepoint_state_offset = 1616;
 static constexpr dart::compiler::target::word
     AOT_Thread_slow_type_test_stub_offset = 472;
 static constexpr dart::compiler::target::word
-    AOT_Thread_slow_type_test_entry_point_offset = 632;
+    AOT_Thread_slow_type_test_entry_point_offset = 640;
 static constexpr dart::compiler::target::word AOT_Thread_stack_limit_offset =
     56;
 static constexpr dart::compiler::target::word
@@ -12589,9 +12884,24 @@
     AOT_Thread_write_barrier_mask_offset = 64;
 static constexpr dart::compiler::target::word AOT_Thread_heap_base_offset = 72;
 static constexpr dart::compiler::target::word AOT_Thread_callback_code_offset =
-    1616;
+    1624;
 static constexpr dart::compiler::target::word
-    AOT_Thread_callback_stack_return_offset = 1624;
+    AOT_Thread_callback_stack_return_offset = 1632;
+static constexpr dart::compiler::target::word AOT_Thread_random_offset = 1664;
+static constexpr dart::compiler::target::word
+    AOT_Thread_jump_to_frame_entry_point_offset = 632;
+static constexpr dart::compiler::target::word AOT_Thread_tsan_utils_offset =
+    1672;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_function_offset = 0;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_setjmp_buffer_offset = 8;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_pc_offset = 16;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_sp_offset = 24;
+static constexpr dart::compiler::target::word
+    AOT_TsanUtils_exception_fp_offset = 32;
 static constexpr dart::compiler::target::word
     AOT_TimelineStream_enabled_offset = 16;
 static constexpr dart::compiler::target::word AOT_TwoByteString_data_offset =
@@ -12665,9 +12975,9 @@
     8, 24, 16, 32};
 static constexpr dart::compiler::target::word
     AOT_Thread_write_barrier_wrappers_thread_offset[] = {
-        1408, 1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488,
-        1496, 1504, 1512, 1520, -1,   -1,   -1,   -1,   1528, 1536, -1,
-        -1,   1544, 1552, 1560, -1,   -1,   -1,   -1,   -1,   -1};
+        1416, 1424, 1432, 1440, 1448, 1456, 1464, 1472, 1480, 1488, 1496,
+        1504, 1512, 1520, 1528, -1,   -1,   -1,   -1,   1536, 1544, -1,
+        -1,   1552, 1560, 1568, -1,   -1,   -1,   -1,   -1,   -1};
 static constexpr dart::compiler::target::word AOT_AbstractType_InstanceSize =
     24;
 static constexpr dart::compiler::target::word AOT_ApiError_InstanceSize = 16;
@@ -12679,7 +12989,9 @@
 static constexpr dart::compiler::target::word AOT_ClosureData_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_CodeSourceMap_HeaderSize = 16;
 static constexpr dart::compiler::target::word
-    AOT_CompressedStackMaps_HeaderSize = 16;
+    AOT_CompressedStackMaps_ObjectHeaderSize = 8;
+static constexpr dart::compiler::target::word
+    AOT_CompressedStackMaps_PayloadHeaderSize = 4;
 static constexpr dart::compiler::target::word AOT_Context_header_size = 16;
 static constexpr dart::compiler::target::word AOT_Double_InstanceSize = 16;
 static constexpr dart::compiler::target::word AOT_DynamicLibrary_InstanceSize =
@@ -12707,6 +13019,8 @@
     AOT_Instructions_UnalignedHeaderSize = 16;
 static constexpr dart::compiler::target::word
     AOT_InstructionsSection_UnalignedHeaderSize = 40;
+static constexpr dart::compiler::target::word
+    AOT_InstructionsTable_InstanceSize = 48;
 static constexpr dart::compiler::target::word AOT_Int32x4_InstanceSize = 24;
 static constexpr dart::compiler::target::word AOT_Integer_InstanceSize = 8;
 static constexpr dart::compiler::target::word
@@ -12763,7 +13077,7 @@
 static constexpr dart::compiler::target::word AOT_UnlinkedCall_InstanceSize =
     32;
 static constexpr dart::compiler::target::word AOT_UnwindError_InstanceSize = 16;
-static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 24;
+static constexpr dart::compiler::target::word AOT_UserTag_InstanceSize = 32;
 static constexpr dart::compiler::target::word AOT_WeakProperty_InstanceSize =
     24;
 static constexpr dart::compiler::target::word
diff --git a/runtime/vm/compiler/runtime_offsets_list.h b/runtime/vm/compiler/runtime_offsets_list.h
index 0d22eca..1328b23 100644
--- a/runtime/vm/compiler/runtime_offsets_list.h
+++ b/runtime/vm/compiler/runtime_offsets_list.h
@@ -51,7 +51,6 @@
   ARRAY(Context, variable_offset)                                              \
   ARRAY(ContextScope, element_offset)                                          \
   ARRAY(ExceptionHandlers, element_offset)                                     \
-  ARRAY(InstructionsTable, element_offset)                                     \
   ARRAY(ObjectPool, element_offset)                                            \
   ARRAY(OneByteString, element_offset)                                         \
   ARRAY(TypeArguments, type_at_offset)                                         \
@@ -61,7 +60,6 @@
   ARRAY_SIZEOF(Context, InstanceSize, variable_offset)                         \
   ARRAY_SIZEOF(ContextScope, InstanceSize, element_offset)                     \
   ARRAY_SIZEOF(ExceptionHandlers, InstanceSize, element_offset)                \
-  ARRAY_SIZEOF(InstructionsTable, InstanceSize, element_offset)                \
   ARRAY_SIZEOF(ObjectPool, InstanceSize, element_offset)                       \
   ARRAY_SIZEOF(OneByteString, InstanceSize, element_offset)                    \
   ARRAY_SIZEOF(TypeArguments, InstanceSize, type_at_offset)                    \
@@ -286,6 +284,14 @@
   FIELD(Thread, heap_base_offset)                                              \
   FIELD(Thread, callback_code_offset)                                          \
   FIELD(Thread, callback_stack_return_offset)                                  \
+  FIELD(Thread, random_offset)                                                 \
+  FIELD(Thread, jump_to_frame_entry_point_offset)                              \
+  FIELD(Thread, tsan_utils_offset)                                             \
+  FIELD(TsanUtils, setjmp_function_offset)                                     \
+  FIELD(TsanUtils, setjmp_buffer_offset)                                       \
+  FIELD(TsanUtils, exception_pc_offset)                                        \
+  FIELD(TsanUtils, exception_sp_offset)                                        \
+  FIELD(TsanUtils, exception_fp_offset)                                        \
   FIELD(TimelineStream, enabled_offset)                                        \
   FIELD(TwoByteString, data_offset)                                            \
   FIELD(Type, arguments_offset)                                                \
@@ -342,7 +348,9 @@
   SIZEOF(Closure, InstanceSize, UntaggedClosure)                               \
   SIZEOF(ClosureData, InstanceSize, UntaggedClosureData)                       \
   SIZEOF(CodeSourceMap, HeaderSize, UntaggedCodeSourceMap)                     \
-  SIZEOF(CompressedStackMaps, HeaderSize, UntaggedCompressedStackMaps)         \
+  SIZEOF(CompressedStackMaps, ObjectHeaderSize, UntaggedCompressedStackMaps)   \
+  SIZEOF(CompressedStackMaps, PayloadHeaderSize,                               \
+         UntaggedCompressedStackMaps::Payload)                                 \
   SIZEOF(Context, header_size, UntaggedContext)                                \
   SIZEOF(Double, InstanceSize, UntaggedDouble)                                 \
   SIZEOF(DynamicLibrary, InstanceSize, UntaggedDynamicLibrary)                 \
@@ -362,6 +370,7 @@
   SIZEOF(Instructions, UnalignedHeaderSize, UntaggedInstructions)              \
   SIZEOF(InstructionsSection, UnalignedHeaderSize,                             \
          UntaggedInstructionsSection)                                          \
+  SIZEOF(InstructionsTable, InstanceSize, UntaggedInstructionsTable)           \
   SIZEOF(Int32x4, InstanceSize, UntaggedInt32x4)                               \
   SIZEOF(Integer, InstanceSize, UntaggedInteger)                               \
   SIZEOF(KernelProgramInfo, InstanceSize, UntaggedKernelProgramInfo)           \
diff --git a/runtime/vm/compiler/stub_code_compiler.cc b/runtime/vm/compiler/stub_code_compiler.cc
index a4c8a57..c4d5c98 100644
--- a/runtime/vm/compiler/stub_code_compiler.cc
+++ b/runtime/vm/compiler/stub_code_compiler.cc
@@ -61,8 +61,7 @@
   __ Comment("Calling initializer function");
   __ PushRegister(kFieldReg);
   __ LoadCompressedFieldFromOffset(
-      kFunctionReg, InitInstanceFieldABI::kFieldReg,
-      target::Field::initializer_function_offset());
+      kFunctionReg, kFieldReg, target::Field::initializer_function_offset());
   if (!FLAG_precompiled_mode) {
     __ LoadCompressedFieldFromOffset(CODE_REG, kFunctionReg,
                                      target::Function::code_offset());
@@ -1073,12 +1072,6 @@
 #undef EMIT_BOX_ALLOCATION
 
 void StubCodeCompiler::GenerateBoxDoubleStub(Assembler* assembler) {
-#if defined(TARGET_ARCH_ARM)
-  if (!TargetCPUFeatures::vfp_supported()) {
-    __ Breakpoint();
-    return;
-  }
-#endif  // defined(TARGET_ARCH_ARM)
   Label call_runtime;
   if (!FLAG_use_slow_path && FLAG_inline_alloc) {
     __ TryAllocate(compiler::DoubleClass(), &call_runtime,
@@ -1101,12 +1094,6 @@
 }
 
 void StubCodeCompiler::GenerateDoubleToIntegerStub(Assembler* assembler) {
-#if defined(TARGET_ARCH_ARM)
-  if (!TargetCPUFeatures::vfp_supported()) {
-    __ Breakpoint();
-    return;
-  }
-#endif  // defined(TARGET_ARCH_ARM)
   __ EnterStubFrame();
   __ StoreUnboxedDouble(DoubleToIntegerStubABI::kInputReg, THR,
                         target::Thread::unboxed_double_runtime_arg_offset());
diff --git a/runtime/vm/compiler/stub_code_compiler_arm.cc b/runtime/vm/compiler/stub_code_compiler_arm.cc
index 859643a..e31e943 100644
--- a/runtime/vm/compiler/stub_code_compiler_arm.cc
+++ b/runtime/vm/compiler/stub_code_compiler_arm.cc
@@ -161,13 +161,6 @@
     intptr_t self_code_stub_offset_from_thread,
     bool allow_return,
     std::function<void()> perform_runtime_call) {
-  // If the target CPU does not support VFP the caller should always use the
-  // non-FPU stub.
-  if (save_fpu_registers && !TargetCPUFeatures::vfp_supported()) {
-    __ Breakpoint();
-    return;
-  }
-
   // We want the saved registers to appear like part of the caller's frame, so
   // we push them before calling EnterStubFrame.
   RegisterSet all_registers;
@@ -825,7 +818,6 @@
     }
   }
 
-  if (TargetCPUFeatures::vfp_supported()) {
     ASSERT(kFpuRegisterSize == 4 * target::kWordSize);
     if (kNumberOfDRegisters > 16) {
       __ vstmd(DB_W, SP, D16, kNumberOfDRegisters - 16);
@@ -833,9 +825,6 @@
     } else {
       __ vstmd(DB_W, SP, D0, kNumberOfDRegisters);
     }
-  } else {
-    __ AddImmediate(SP, -kNumberOfFpuRegisters * kFpuRegisterSize);
-  }
 
   __ mov(R0, Operand(SP));  // Pass address of saved registers block.
   bool is_lazy =
diff --git a/runtime/vm/compiler/stub_code_compiler_x64.cc b/runtime/vm/compiler/stub_code_compiler_x64.cc
index 07f9c00..ae87dca 100644
--- a/runtime/vm/compiler/stub_code_compiler_x64.cc
+++ b/runtime/vm/compiler/stub_code_compiler_x64.cc
@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+#include <setjmp.h>
+
 #include "vm/compiler/runtime_api.h"
 #include "vm/globals.h"
 
@@ -58,6 +60,102 @@
   __ Bind(&done);
 }
 
+// In TSAN mode the runtime will throw an exception using an intermediary
+// longjmp() call to unwind the C frames in a way that TSAN can understand.
+//
+// This wrapper will setup a [jmp_buf] on the stack and initialize it to be a
+// target for a possible longjmp(). In the exceptional case we'll forward
+// control of execution to the usual JumpToFrame stub.
+//
+// In non-TSAN mode this will do nothing and the runtime will call the
+// JumpToFrame stub directly.
+//
+// The callback [fun] may be invoked with a modified [RSP] due to allocating
+// a [jmp_buf] allocating structure on the stack (as well as the saved old
+// [Thread::tsan_utils_->setjmp_buffer_]).
+static void WithExceptionCatchingTrampoline(Assembler* assembler,
+                                            std::function<void()> fun) {
+#if defined(USING_THREAD_SANITIZER)
+  const Register kTsanUtilsReg = RAX;
+
+  // Reserve space for arguments and align frame before entering C++ world.
+  const intptr_t kJumpBufferSize = sizeof(jmp_buf);
+  // Save & Restore the volatile CPU registers across the setjmp() call.
+  const RegisterSet volatile_registers(
+      CallingConventions::kVolatileCpuRegisters & ~(1 << RAX),
+      /*fpu_registers=*/0);
+
+  const Register kSavedRspReg = R12;
+  COMPILE_ASSERT(IsCalleeSavedRegister(kSavedRspReg));
+  // We rely on THR being preserved across the setjmp() call.
+  COMPILE_ASSERT(IsCalleeSavedRegister(THR));
+
+  Label do_native_call;
+
+  // Save old jmp_buf.
+  __ movq(kTsanUtilsReg, Address(THR, target::Thread::tsan_utils_offset()));
+  __ pushq(Address(kTsanUtilsReg, target::TsanUtils::setjmp_buffer_offset()));
+
+  // Allocate jmp_buf struct on stack & remember pointer to it on the
+  // [Thread::tsan_utils_->setjmp_buffer] (which exceptions.cc will longjmp()
+  // to)
+  __ AddImmediate(RSP, Immediate(-kJumpBufferSize));
+  __ movq(Address(kTsanUtilsReg, target::TsanUtils::setjmp_buffer_offset()),
+          RSP);
+
+  // Call setjmp() with a pointer to the allocated jmp_buf struct.
+  __ MoveRegister(CallingConventions::kArg1Reg, RSP);
+  __ PushRegisters(volatile_registers);
+  if (OS::ActivationFrameAlignment() > 1) {
+    __ MoveRegister(kSavedRspReg, RSP);
+    __ andq(RSP, Immediate(~(OS::ActivationFrameAlignment() - 1)));
+  }
+  __ movq(kTsanUtilsReg, Address(THR, target::Thread::tsan_utils_offset()));
+  __ CallCFunction(
+      Address(kTsanUtilsReg, target::TsanUtils::setjmp_function_offset()),
+      /*restore_rsp=*/true);
+  if (OS::ActivationFrameAlignment() > 1) {
+    __ MoveRegister(RSP, kSavedRspReg);
+  }
+  __ PopRegisters(volatile_registers);
+
+  // We are the target of a longjmp() iff setjmp() returns non-0.
+  __ CompareImmediate(RAX, 0);
+  __ BranchIf(EQUAL, &do_native_call);
+
+  // We are the target of a longjmp: Cleanup the stack and tail-call the
+  // JumpToFrame stub which will take care of unwinding the stack and hand
+  // execution to the catch entry.
+  __ AddImmediate(RSP, Immediate(kJumpBufferSize));
+  __ movq(kTsanUtilsReg, Address(THR, target::Thread::tsan_utils_offset()));
+  __ popq(Address(kTsanUtilsReg, target::TsanUtils::setjmp_buffer_offset()));
+
+  __ movq(CallingConventions::kArg1Reg,
+          Address(kTsanUtilsReg, target::TsanUtils::exception_pc_offset()));
+  __ movq(CallingConventions::kArg2Reg,
+          Address(kTsanUtilsReg, target::TsanUtils::exception_sp_offset()));
+  __ movq(CallingConventions::kArg3Reg,
+          Address(kTsanUtilsReg, target::TsanUtils::exception_fp_offset()));
+  __ MoveRegister(CallingConventions::kArg4Reg, THR);
+  __ jmp(Address(THR, target::Thread::jump_to_frame_entry_point_offset()));
+
+  // We leave the created [jump_buf] structure on the stack as well as the
+  // pushed old [Thread::tsan_utils_->setjmp_buffer_].
+  __ Bind(&do_native_call);
+  __ MoveRegister(kSavedRspReg, RSP);
+#endif  // defined(USING_THREAD_SANITIZER)
+
+  fun();
+
+#if defined(USING_THREAD_SANITIZER)
+  __ MoveRegister(RSP, kSavedRspReg);
+  __ AddImmediate(RSP, Immediate(kJumpBufferSize));
+  const Register kTsanUtilsReg2 = kSavedRspReg;
+  __ movq(kTsanUtilsReg2, Address(THR, target::Thread::tsan_utils_offset()));
+  __ popq(Address(kTsanUtilsReg2, target::TsanUtils::setjmp_buffer_offset()));
+#endif  // defined(USING_THREAD_SANITIZER)
+}
+
 // Input parameters:
 //   RSP : points to return address.
 //   RSP + 8 : address of last argument in argument array.
@@ -99,51 +197,54 @@
   // Mark that the thread is executing VM code.
   __ movq(Assembler::VMTagAddress(), RBX);
 
-  // Reserve space for arguments and align frame before entering C++ world.
-  __ subq(RSP, Immediate(target::NativeArguments::StructSize()));
-  if (OS::ActivationFrameAlignment() > 1) {
-    __ andq(RSP, Immediate(~(OS::ActivationFrameAlignment() - 1)));
-  }
+  WithExceptionCatchingTrampoline(assembler, [&]() {
+    // Reserve space for arguments and align frame before entering C++ world.
+    __ subq(RSP, Immediate(target::NativeArguments::StructSize()));
+    if (OS::ActivationFrameAlignment() > 1) {
+      __ andq(RSP, Immediate(~(OS::ActivationFrameAlignment() - 1)));
+    }
 
-  // Pass target::NativeArguments structure by value and call runtime.
-  __ movq(Address(RSP, thread_offset), THR);  // Set thread in NativeArgs.
-  // There are no runtime calls to closures, so we do not need to set the tag
-  // bits kClosureFunctionBit and kInstanceFunctionBit in argc_tag_.
-  __ movq(Address(RSP, argc_tag_offset),
-          R10);  // Set argc in target::NativeArguments.
-  // Compute argv.
-  __ leaq(RAX,
-          Address(RBP, R10, TIMES_8,
-                  target::frame_layout.param_end_from_fp * target::kWordSize));
-  __ movq(Address(RSP, argv_offset),
-          RAX);  // Set argv in target::NativeArguments.
-  __ addq(RAX,
-          Immediate(1 * target::kWordSize));  // Retval is next to 1st argument.
-  __ movq(Address(RSP, retval_offset),
-          RAX);  // Set retval in target::NativeArguments.
+    // Pass target::NativeArguments structure by value and call runtime.
+    __ movq(Address(RSP, thread_offset), THR);  // Set thread in NativeArgs.
+    // There are no runtime calls to closures, so we do not need to set the tag
+    // bits kClosureFunctionBit and kInstanceFunctionBit in argc_tag_.
+    __ movq(Address(RSP, argc_tag_offset),
+            R10);  // Set argc in target::NativeArguments.
+    // Compute argv.
+    __ leaq(RAX, Address(RBP, R10, TIMES_8,
+                         target::frame_layout.param_end_from_fp *
+                             target::kWordSize));
+    __ movq(Address(RSP, argv_offset),
+            RAX);  // Set argv in target::NativeArguments.
+    __ addq(
+        RAX,
+        Immediate(1 * target::kWordSize));  // Retval is next to 1st argument.
+    __ movq(Address(RSP, retval_offset),
+            RAX);  // Set retval in target::NativeArguments.
 #if defined(DART_TARGET_OS_WINDOWS)
-  ASSERT(target::NativeArguments::StructSize() >
-         CallingConventions::kRegisterTransferLimit);
-  __ movq(CallingConventions::kArg1Reg, RSP);
+    ASSERT(target::NativeArguments::StructSize() >
+           CallingConventions::kRegisterTransferLimit);
+    __ movq(CallingConventions::kArg1Reg, RSP);
 #endif
-  __ CallCFunction(RBX);
+    __ CallCFunction(RBX);
 
-  // Mark that the thread is executing Dart code.
-  __ movq(Assembler::VMTagAddress(), Immediate(VMTag::kDartTagId));
+    // Mark that the thread is executing Dart code.
+    __ movq(Assembler::VMTagAddress(), Immediate(VMTag::kDartTagId));
 
-  // Mark that the thread has not exited generated Dart code.
-  __ movq(Address(THR, target::Thread::exit_through_ffi_offset()),
-          Immediate(0));
+    // Mark that the thread has not exited generated Dart code.
+    __ movq(Address(THR, target::Thread::exit_through_ffi_offset()),
+            Immediate(0));
 
-  // Reset exit frame information in Isolate's mutator thread structure.
-  __ movq(Address(THR, target::Thread::top_exit_frame_info_offset()),
-          Immediate(0));
+    // Reset exit frame information in Isolate's mutator thread structure.
+    __ movq(Address(THR, target::Thread::top_exit_frame_info_offset()),
+            Immediate(0));
 
-  // Restore the global object pool after returning from runtime (old space is
-  // moving, so the GOP could have been relocated).
-  if (FLAG_precompiled_mode) {
-    __ movq(PP, Address(THR, target::Thread::global_object_pool_offset()));
-  }
+    // Restore the global object pool after returning from runtime (old space is
+    // moving, so the GOP could have been relocated).
+    if (FLAG_precompiled_mode) {
+      __ movq(PP, Address(THR, target::Thread::global_object_pool_offset()));
+    }
+  });
 
   __ LeaveStubFrame();
 
@@ -565,7 +666,7 @@
 // Input parameters:
 //   RSP : points to return address.
 //   RSP + 8 : address of return value.
-//   RAX : address of first argument in argument array.
+//   R13 : address of first argument in argument array.
 //   RBX : address of the native function to call.
 //   R10 : argc_tag including number of arguments and function kind.
 static void GenerateCallNativeWithWrapperStub(Assembler* assembler,
@@ -605,49 +706,51 @@
   // Mark that the thread is executing native code.
   __ movq(Assembler::VMTagAddress(), RBX);
 
-  // Reserve space for the native arguments structure passed on the stack (the
-  // outgoing pointer parameter to the native arguments structure is passed in
-  // RDI) and align frame before entering the C++ world.
-  __ subq(RSP, Immediate(target::NativeArguments::StructSize()));
-  if (OS::ActivationFrameAlignment() > 1) {
-    __ andq(RSP, Immediate(~(OS::ActivationFrameAlignment() - 1)));
-  }
+  WithExceptionCatchingTrampoline(assembler, [&]() {
+    // Reserve space for the native arguments structure passed on the stack (the
+    // outgoing pointer parameter to the native arguments structure is passed in
+    // RDI) and align frame before entering the C++ world.
+    __ subq(RSP, Immediate(target::NativeArguments::StructSize()));
+    if (OS::ActivationFrameAlignment() > 1) {
+      __ andq(RSP, Immediate(~(OS::ActivationFrameAlignment() - 1)));
+    }
 
-  // Pass target::NativeArguments structure by value and call native function.
-  __ movq(Address(RSP, thread_offset), THR);  // Set thread in NativeArgs.
-  __ movq(Address(RSP, argc_tag_offset),
-          R10);  // Set argc in target::NativeArguments.
-  __ movq(Address(RSP, argv_offset),
-          RAX);  // Set argv in target::NativeArguments.
-  __ leaq(RAX,
-          Address(RBP, 2 * target::kWordSize));  // Compute return value addr.
-  __ movq(Address(RSP, retval_offset),
-          RAX);  // Set retval in target::NativeArguments.
+    // Pass target::NativeArguments structure by value and call native function.
+    __ movq(Address(RSP, thread_offset), THR);  // Set thread in NativeArgs.
+    __ movq(Address(RSP, argc_tag_offset),
+            R10);  // Set argc in target::NativeArguments.
+    __ movq(Address(RSP, argv_offset),
+            R13);  // Set argv in target::NativeArguments.
+    __ leaq(RAX,
+            Address(RBP, 2 * target::kWordSize));  // Compute return value addr.
+    __ movq(Address(RSP, retval_offset),
+            RAX);  // Set retval in target::NativeArguments.
 
-  // Pass the pointer to the target::NativeArguments.
-  __ movq(CallingConventions::kArg1Reg, RSP);
-  // Pass pointer to function entrypoint.
-  __ movq(CallingConventions::kArg2Reg, RBX);
+    // Pass the pointer to the target::NativeArguments.
+    __ movq(CallingConventions::kArg1Reg, RSP);
+    // Pass pointer to function entrypoint.
+    __ movq(CallingConventions::kArg2Reg, RBX);
 
-  __ movq(RAX, wrapper_address);
-  __ CallCFunction(RAX);
+    __ movq(RAX, wrapper_address);
+    __ CallCFunction(RAX);
 
-  // Mark that the thread is executing Dart code.
-  __ movq(Assembler::VMTagAddress(), Immediate(VMTag::kDartTagId));
+    // Mark that the thread is executing Dart code.
+    __ movq(Assembler::VMTagAddress(), Immediate(VMTag::kDartTagId));
 
-  // Mark that the thread has not exited generated Dart code.
-  __ movq(Address(THR, target::Thread::exit_through_ffi_offset()),
-          Immediate(0));
+    // Mark that the thread has not exited generated Dart code.
+    __ movq(Address(THR, target::Thread::exit_through_ffi_offset()),
+            Immediate(0));
 
-  // Reset exit frame information in Isolate's mutator thread structure.
-  __ movq(Address(THR, target::Thread::top_exit_frame_info_offset()),
-          Immediate(0));
+    // Reset exit frame information in Isolate's mutator thread structure.
+    __ movq(Address(THR, target::Thread::top_exit_frame_info_offset()),
+            Immediate(0));
 
-  // Restore the global object pool after returning from runtime (old space is
-  // moving, so the GOP could have been relocated).
-  if (FLAG_precompiled_mode) {
-    __ movq(PP, Address(THR, target::Thread::global_object_pool_offset()));
-  }
+    // Restore the global object pool after returning from runtime (old space is
+    // moving, so the GOP could have been relocated).
+    if (FLAG_precompiled_mode) {
+      __ movq(PP, Address(THR, target::Thread::global_object_pool_offset()));
+    }
+  });
 
   __ LeaveStubFrame();
   __ ret();
diff --git a/runtime/vm/compiler/write_barrier_elimination_test.cc b/runtime/vm/compiler/write_barrier_elimination_test.cc
index 936d432..1275b14 100644
--- a/runtime/vm/compiler/write_barrier_elimination_test.cc
+++ b/runtime/vm/compiler/write_barrier_elimination_test.cc
@@ -298,8 +298,59 @@
       },
       kMoveGlob));
 
-  EXPECT(store1->ShouldEmitStoreBarrier());
-  EXPECT(store2->ShouldEmitStoreBarrier());
+  EXPECT(!store1->ShouldEmitStoreBarrier());
+  EXPECT(!store2->ShouldEmitStoreBarrier());
+}
+
+ISOLATE_UNIT_TEST_CASE(IRTest_WriteBarrierElimination_LoadLateStaticField) {
+  DEBUG_ONLY(
+      SetFlagScope<bool> sfs(&FLAG_trace_write_barrier_elimination, true));
+  const char* kScript = R"(
+    class A {
+    }
+
+    class B {
+    }
+
+    class C {
+      C(this.a, this.b);
+      A a;
+      B b;
+    }
+
+    late var x = new B();
+
+    foo(A a) => C(a, x);
+
+    main() { foo(A()); }
+    )";
+
+  const auto& root_library = Library::Handle(LoadTestScript(kScript));
+
+  Invoke(root_library, "main");
+
+  const auto& function = Function::Handle(GetFunction(root_library, "foo"));
+  TestPipeline pipeline(function, CompilerPass::kJIT);
+  FlowGraph* flow_graph = pipeline.RunPasses({});
+
+  auto entry = flow_graph->graph_entry()->normal_entry();
+  EXPECT(entry != nullptr);
+
+  StoreInstanceFieldInstr* store1 = nullptr;
+  StoreInstanceFieldInstr* store2 = nullptr;
+
+  ILMatcher cursor(flow_graph, entry);
+  RELEASE_ASSERT(cursor.TryMatch(
+      {
+          kMatchAndMoveAllocateObject,
+          kMatchAndMoveLoadStaticField,
+          {kMatchAndMoveStoreInstanceField, &store1},
+          {kMatchAndMoveStoreInstanceField, &store2},
+      },
+      kMoveGlob));
+
+  EXPECT(!store1->ShouldEmitStoreBarrier());
+  EXPECT(!store2->ShouldEmitStoreBarrier());
 }
 
 }  // namespace dart
diff --git a/runtime/vm/cpu_arm.cc b/runtime/vm/cpu_arm.cc
index 6d300fb..284b62d 100644
--- a/runtime/vm/cpu_arm.cc
+++ b/runtime/vm/cpu_arm.cc
@@ -49,7 +49,6 @@
 
 namespace dart {
 
-DEFINE_FLAG(bool, use_vfp, true, "Use vfp instructions if supported");
 DEFINE_FLAG(bool, use_neon, true, "Use neon instructions if supported");
 DEFINE_FLAG(bool,
             use_integer_division,
@@ -104,7 +103,6 @@
 }
 
 bool HostCPUFeatures::integer_division_supported_ = false;
-bool HostCPUFeatures::vfp_supported_ = false;
 bool HostCPUFeatures::neon_supported_ = false;
 bool HostCPUFeatures::hardfp_supported_ = false;
 const char* HostCPUFeatures::hardware_ = NULL;
@@ -121,7 +119,6 @@
   hardware_ = "";
   // When the VM is targetted to ARMv7, pretend that the CPU is ARMv7 even if
   // the CPU is actually AArch64.
-  vfp_supported_ = FLAG_use_vfp;
   integer_division_supported_ = FLAG_use_integer_division;
   neon_supported_ = FLAG_use_neon;
   hardfp_supported_ = false;
@@ -151,15 +148,6 @@
 #endif
   }
 
-#if defined(DART_RUN_IN_QEMU_ARMv7)
-  vfp_supported_ = true;
-#else
-  // Has floating point unit.
-  vfp_supported_ =
-      (CpuInfo::FieldContains(kCpuInfoFeatures, "vfp") || is_arm64) &&
-      FLAG_use_vfp;
-#endif
-
   // Has integer division.
   // Special cases:
   // - Qualcomm Krait CPUs (QCT APQ8064) in Nexus 4 and 7 incorrectly report
@@ -198,7 +186,7 @@
   }
   neon_supported_ =
       (CpuInfo::FieldContains(kCpuInfoFeatures, "neon") || is_arm64) &&
-      FLAG_use_vfp && FLAG_use_neon;
+      FLAG_use_neon;
 
 // Use the cross-compiler's predefined macros to determine whether we should
 // use the hard or soft float ABI.
@@ -232,8 +220,7 @@
   hardware_ = CpuInfo::GetCpuModel();
 
   integer_division_supported_ = FLAG_use_integer_division;
-  vfp_supported_ = FLAG_use_vfp;
-  neon_supported_ = FLAG_use_vfp && FLAG_use_neon;
+  neon_supported_ = FLAG_use_neon;
   hardfp_supported_ = FLAG_sim_use_hardfp;
 #if defined(DEBUG)
   initialized_ = true;
diff --git a/runtime/vm/cpu_arm.h b/runtime/vm/cpu_arm.h
index 2eaf4aa..a6cb9d7 100644
--- a/runtime/vm/cpu_arm.h
+++ b/runtime/vm/cpu_arm.h
@@ -10,6 +10,7 @@
 #endif
 
 #include "vm/allocation.h"
+#include "vm/flags.h"
 #include "vm/simulator.h"
 
 namespace dart {
@@ -32,11 +33,7 @@
   }
   static bool integer_division_supported() {
     DEBUG_ASSERT(initialized_);
-    return integer_division_supported_;
-  }
-  static bool vfp_supported() {
-    DEBUG_ASSERT(initialized_);
-    return vfp_supported_;
+    return integer_division_supported_ && !FLAG_target_unknown_cpu;
   }
   static bool neon_supported() {
     DEBUG_ASSERT(initialized_);
@@ -56,10 +53,6 @@
     DEBUG_ASSERT(initialized_);
     integer_division_supported_ = supported;
   }
-  static void set_vfp_supported(bool supported) {
-    DEBUG_ASSERT(initialized_);
-    vfp_supported_ = supported;
-  }
   static void set_neon_supported(bool supported) {
     DEBUG_ASSERT(initialized_);
     neon_supported_ = supported;
@@ -69,7 +62,6 @@
  private:
   static const char* hardware_;
   static bool integer_division_supported_;
-  static bool vfp_supported_;
   static bool neon_supported_;
   static bool hardfp_supported_;
   static intptr_t store_pc_read_offset_;
@@ -86,10 +78,6 @@
   static bool integer_division_supported() {
     return HostCPUFeatures::integer_division_supported();
   }
-  static bool vfp_supported() { return HostCPUFeatures::vfp_supported(); }
-  static bool can_divide() {
-    return integer_division_supported() || vfp_supported();
-  }
   static bool neon_supported() { return HostCPUFeatures::neon_supported(); }
   static bool hardfp_supported() { return HostCPUFeatures::hardfp_supported(); }
   static const char* hardware() { return HostCPUFeatures::hardware(); }
diff --git a/runtime/vm/cpu_arm64.h b/runtime/vm/cpu_arm64.h
index 5fa7b2e..3e793ef 100644
--- a/runtime/vm/cpu_arm64.h
+++ b/runtime/vm/cpu_arm64.h
@@ -10,6 +10,7 @@
 #endif
 
 #include "vm/allocation.h"
+#include "vm/flags.h"
 #include "vm/simulator.h"
 
 namespace dart {
diff --git a/runtime/vm/cpu_ia32.h b/runtime/vm/cpu_ia32.h
index f622c1f..0fe8ba0 100644
--- a/runtime/vm/cpu_ia32.h
+++ b/runtime/vm/cpu_ia32.h
@@ -30,15 +30,15 @@
   }
   static bool sse4_1_supported() {
     DEBUG_ASSERT(initialized_);
-    return sse4_1_supported_ && FLAG_use_sse41;
+    return sse4_1_supported_ && FLAG_use_sse41 && !FLAG_target_unknown_cpu;
   }
   static bool popcnt_supported() {
     DEBUG_ASSERT(initialized_);
-    return popcnt_supported_;
+    return popcnt_supported_ && !FLAG_target_unknown_cpu;
   }
   static bool abm_supported() {
     DEBUG_ASSERT(initialized_);
-    return abm_supported_;
+    return abm_supported_ && !FLAG_target_unknown_cpu;
   }
 
  private:
diff --git a/runtime/vm/cpu_x64.h b/runtime/vm/cpu_x64.h
index d0d1a14..c444be8 100644
--- a/runtime/vm/cpu_x64.h
+++ b/runtime/vm/cpu_x64.h
@@ -30,15 +30,15 @@
   }
   static bool sse4_1_supported() {
     DEBUG_ASSERT(initialized_);
-    return sse4_1_supported_ && FLAG_use_sse41;
+    return sse4_1_supported_ && FLAG_use_sse41 && !FLAG_target_unknown_cpu;
   }
   static bool popcnt_supported() {
     DEBUG_ASSERT(initialized_);
-    return popcnt_supported_;
+    return popcnt_supported_ && !FLAG_target_unknown_cpu;
   }
   static bool abm_supported() {
     DEBUG_ASSERT(initialized_);
-    return abm_supported_;
+    return abm_supported_ && !FLAG_target_unknown_cpu;
   }
 
  private:
diff --git a/runtime/vm/dart.cc b/runtime/vm/dart.cc
index e18e2a3..9f78ed8 100644
--- a/runtime/vm/dart.cc
+++ b/runtime/vm/dart.cc
@@ -44,6 +44,7 @@
 #include "vm/stack_frame.h"
 #include "vm/stub_code.h"
 #include "vm/symbols.h"
+#include "vm/tags.h"
 #include "vm/thread_interrupter.h"
 #include "vm/thread_pool.h"
 #include "vm/timeline.h"
@@ -340,6 +341,7 @@
 #endif
   IsolateGroup::Init();
   Isolate::InitVM();
+  UserTags::Init();
   PortMap::Init();
   FreeListElement::Init();
   ForwardingCorpse::Init();
@@ -801,6 +803,7 @@
   vm_isolate_ = NULL;
   ASSERT(Isolate::IsolateListLength() == 0);
   PortMap::Cleanup();
+  UserTags::Cleanup();
   IsolateGroup::Cleanup();
   ICData::Cleanup();
   SubtypeTestCache::Cleanup();
@@ -1173,6 +1176,8 @@
       ADD_ISOLATE_GROUP_FLAG(use_field_guards, use_field_guards,
                              FLAG_use_field_guards);
       ADD_ISOLATE_GROUP_FLAG(use_osr, use_osr, FLAG_use_osr);
+      ADD_ISOLATE_GROUP_FLAG(branch_coverage, branch_coverage,
+                             FLAG_branch_coverage);
     }
 
 // Generated code must match the host architecture and ABI.
diff --git a/runtime/vm/dart_api_impl_test.cc b/runtime/vm/dart_api_impl_test.cc
index 5a9050a..02cbfa3 100644
--- a/runtime/vm/dart_api_impl_test.cc
+++ b/runtime/vm/dart_api_impl_test.cc
@@ -7854,7 +7854,8 @@
                "'foo1:///.dart_tool");
 }
 
-void NewNativePort_send123(Dart_Port dest_port_id, Dart_CObject* message) {
+static void NewNativePort_send123(Dart_Port dest_port_id,
+                                  Dart_CObject* message) {
   // Gets a send port message.
   EXPECT_NOTNULL(message);
   EXPECT_EQ(Dart_CObject_kArray, message->type);
@@ -7869,7 +7870,8 @@
                    response);
 }
 
-void NewNativePort_send321(Dart_Port dest_port_id, Dart_CObject* message) {
+static void NewNativePort_send321(Dart_Port dest_port_id,
+                                  Dart_CObject* message) {
   // Gets a null message.
   EXPECT_NOTNULL(message);
   EXPECT_EQ(Dart_CObject_kArray, message->type);
@@ -7978,8 +7980,8 @@
   EXPECT(Dart_CloseNativePort(port_id2));
 }
 
-void NewNativePort_sendInteger123(Dart_Port dest_port_id,
-                                  Dart_CObject* message) {
+static void NewNativePort_sendInteger123(Dart_Port dest_port_id,
+                                         Dart_CObject* message) {
   // Gets a send port message.
   EXPECT_NOTNULL(message);
   EXPECT_EQ(Dart_CObject_kArray, message->type);
@@ -7990,8 +7992,8 @@
                    123);
 }
 
-void NewNativePort_sendInteger321(Dart_Port dest_port_id,
-                                  Dart_CObject* message) {
+static void NewNativePort_sendInteger321(Dart_Port dest_port_id,
+                                         Dart_CObject* message) {
   // Gets a null message.
   EXPECT_NOTNULL(message);
   EXPECT_EQ(Dart_CObject_kArray, message->type);
@@ -8053,8 +8055,132 @@
   EXPECT(Dart_CloseNativePort(port_id2));
 }
 
-void NewNativePort_nativeReceiveNull(Dart_Port dest_port_id,
-                                     Dart_CObject* message) {
+static void NewNativePort_Transferrable1(Dart_Port dest_port_id,
+                                         Dart_CObject* message) {
+  // Gets a send port message.
+  EXPECT_NOTNULL(message);
+  EXPECT_EQ(Dart_CObject_kTypedData, message->type);
+  EXPECT_EQ(Dart_TypedData_kUint8, message->value.as_typed_data.type);
+  EXPECT_EQ(10, message->value.as_typed_data.length);
+  EXPECT_EQ(42, message->value.as_typed_data.values[0]);
+  free(message->value.as_typed_data.values);
+}
+
+static void NewNativePort_Transferrable2(Dart_Port dest_port_id,
+                                         Dart_CObject* message) {
+  // Gets a send port message.
+  EXPECT_NOTNULL(message);
+  EXPECT_EQ(Dart_CObject_kArray, message->type);
+  EXPECT_EQ(1, message->value.as_array.length);
+  Dart_CObject* cobj = message->value.as_array.values[0];
+  EXPECT_EQ(Dart_CObject_kTypedData, cobj->type);
+  EXPECT_EQ(Dart_TypedData_kUint8, cobj->value.as_typed_data.type);
+  EXPECT_EQ(10, cobj->value.as_typed_data.length);
+  EXPECT_EQ(42, cobj->value.as_typed_data.values[0]);
+  free(cobj->value.as_typed_data.values);
+}
+
+TEST_CASE(DartAPI_NativePortPostTransferrableTypedData) {
+  const char* kScriptChars =
+      "import 'dart:typed_data';\n"
+      "import 'dart:isolate';\n"
+      "void callPort(SendPort port1, SendPort port2) {\n"
+      "  final td1 ="
+      "     TransferableTypedData.fromList([Uint8List(10)..[0] = 42]);\n"
+      "  final td2 ="
+      "     TransferableTypedData.fromList([Uint8List(10)..[0] = 42]);\n"
+      "  port1.send(td1);\n"
+      "  port2.send([td2]);\n"
+      "}\n";
+  Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
+  Dart_EnterScope();
+
+  Dart_Port port_id1 =
+      Dart_NewNativePort("Port123", NewNativePort_Transferrable1, true);
+  Dart_Port port_id2 =
+      Dart_NewNativePort("Port321", NewNativePort_Transferrable2, true);
+
+  Dart_Handle send_port1 = Dart_NewSendPort(port_id1);
+  EXPECT_VALID(send_port1);
+  Dart_Handle send_port2 = Dart_NewSendPort(port_id2);
+  EXPECT_VALID(send_port2);
+
+  // Test first port.
+  Dart_Handle dart_args[2];
+  dart_args[0] = send_port1;
+  dart_args[1] = send_port2;
+  Dart_Handle result = Dart_Invoke(lib, NewString("callPort"), 2, dart_args);
+  EXPECT_VALID(result);
+  result = Dart_RunLoop();
+  EXPECT_VALID(result);
+
+  Dart_ExitScope();
+
+  // Delete the native ports.
+  EXPECT(Dart_CloseNativePort(port_id1));
+  EXPECT(Dart_CloseNativePort(port_id2));
+}
+
+static const intptr_t kSendLength = 16;
+
+static void NewNativePort_ExternalTypedData(Dart_Port dest_port_id,
+                                            Dart_CObject* message) {
+  // Gets a send port message.
+  EXPECT_NOTNULL(message);
+  EXPECT_EQ(Dart_CObject_kTypedData, message->type);
+  EXPECT_EQ(Dart_TypedData_kUint8, message->value.as_typed_data.type);
+  EXPECT_EQ(kSendLength, message->value.as_typed_data.length);
+  for (intptr_t i = 0; i < kSendLength; i++) {
+    EXPECT_EQ((0x41 + i), message->value.as_typed_data.values[i]);
+  }
+}
+
+static void FinalizeTypedData(void* isolate_callback_data, void* peer) {
+  delete[] reinterpret_cast<int8_t*>(peer);
+}
+
+TEST_CASE(DartAPI_NativePortPostExternalTypedData) {
+  int8_t* extTypedData = new int8_t[kSendLength];
+  for (int i = 0; i < kSendLength; i++) {
+    extTypedData[i] = 0x41 + i;
+  }
+  const char* kScriptChars =
+      "import 'dart:typed_data';\n"
+      "import 'dart:isolate';\n"
+      "void callPort(SendPort port, Uint8List data) {\n"
+      "  port.send(data);\n"
+      "}\n";
+  Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
+  Dart_EnterScope();
+
+  Dart_Port port_id =
+      Dart_NewNativePort("Port123", NewNativePort_ExternalTypedData, true);
+
+  Dart_Handle send_port = Dart_NewSendPort(port_id);
+  EXPECT_VALID(send_port);
+
+  Dart_Handle extdata = Dart_NewExternalTypedDataWithFinalizer(
+      Dart_TypedData_kUint8, extTypedData, kSendLength, extTypedData,
+      kSendLength, FinalizeTypedData);
+  EXPECT_VALID(extdata);
+
+  // Test first port.
+  Dart_Handle dart_args[2];
+  dart_args[0] = send_port;
+  dart_args[1] = extdata;
+  Dart_Handle result = Dart_Invoke(lib, NewString("callPort"), 2, dart_args);
+  EXPECT_VALID(result);
+  result = Dart_RunLoop();
+  EXPECT_VALID(result);
+
+  Dart_ExitScope();
+
+  // Delete the native ports.
+  EXPECT(Dart_CloseNativePort(port_id));
+}
+
+static void NewNativePort_nativeReceiveNull(Dart_Port dest_port_id,
+                                            Dart_CObject* message) {
   EXPECT_NOTNULL(message);
 
   if ((message->type == Dart_CObject_kArray) &&
@@ -8104,8 +8230,8 @@
   EXPECT(Dart_CloseNativePort(port_id1));
 }
 
-void NewNativePort_nativeReceiveInteger(Dart_Port dest_port_id,
-                                        Dart_CObject* message) {
+static void NewNativePort_nativeReceiveInteger(Dart_Port dest_port_id,
+                                               Dart_CObject* message) {
   EXPECT_NOTNULL(message);
 
   if ((message->type == Dart_CObject_kArray) &&
diff --git a/runtime/vm/dart_entry.cc b/runtime/vm/dart_entry.cc
index 7041084..46df59f 100644
--- a/runtime/vm/dart_entry.cc
+++ b/runtime/vm/dart_entry.cc
@@ -676,24 +676,6 @@
   return result.ptr();
 }
 
-// On success, returns an InstancePtr.  On failure, an ErrorPtr.
-ObjectPtr DartLibraryCalls::IdentityHashCode(const Instance& object) {
-  const int kNumArguments = 1;
-  Thread* thread = Thread::Current();
-  Zone* zone = thread->zone();
-  const Library& libcore = Library::Handle(zone, Library::CoreLibrary());
-  ASSERT(!libcore.IsNull());
-  const Function& function = Function::Handle(
-      zone, libcore.LookupFunctionAllowPrivate(Symbols::identityHashCode()));
-  ASSERT(!function.IsNull());
-  const Array& args = Array::Handle(zone, Array::New(kNumArguments));
-  args.SetAt(0, object);
-  const Object& result =
-      Object::Handle(zone, DartEntry::InvokeFunction(function, args));
-  ASSERT(result.IsInstance() || result.IsError());
-  return result.ptr();
-}
-
 ObjectPtr DartLibraryCalls::LookupHandler(Dart_Port port_id) {
   Thread* thread = Thread::Current();
   Zone* zone = thread->zone();
diff --git a/runtime/vm/dart_entry.h b/runtime/vm/dart_entry.h
index 6ec9067..4f650a8 100644
--- a/runtime/vm/dart_entry.h
+++ b/runtime/vm/dart_entry.h
@@ -285,9 +285,6 @@
   // On success, returns an InstancePtr. On failure, an ErrorPtr.
   static ObjectPtr Equals(const Instance& left, const Instance& right);
 
-  // On success, returns an InstancePtr. On failure, an ErrorPtr.
-  static ObjectPtr IdentityHashCode(const Instance& object);
-
   // Returns the handler if one has been registered for this port id.
   static ObjectPtr LookupHandler(Dart_Port port_id);
 
diff --git a/runtime/vm/exceptions.cc b/runtime/vm/exceptions.cc
index 95787d7..fc6e47b 100644
--- a/runtime/vm/exceptions.cc
+++ b/runtime/vm/exceptions.cc
@@ -2,9 +2,12 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+#include <setjmp.h>
+
 #include "vm/exceptions.h"
 
 #include "platform/address_sanitizer.h"
+#include "platform/thread_sanitizer.h"
 
 #include "lib/stacktrace.h"
 
@@ -612,13 +615,6 @@
   // in the previous frames.
   StackResource::Unwind(thread);
 
-  // Call a stub to set up the exception object in kExceptionObjectReg,
-  // to set up the stacktrace object in kStackTraceObjectReg, and to
-  // continue execution at the given pc in the given frame.
-  typedef void (*ExcpHandler)(uword, uword, uword, Thread*);
-  ExcpHandler func =
-      reinterpret_cast<ExcpHandler>(StubCode::JumpToFrame().EntryPoint());
-
   // Unpoison the stack before we tear it down in the generated stub code.
   uword current_sp = OSThread::GetCurrentStackPointer() - 1024;
   ASAN_UNPOISON(reinterpret_cast<void*>(current_sp),
@@ -635,7 +631,27 @@
   // The shadow call stack register will be restored by the JumpToFrame stub.
 #endif
 
+  // TODO(b/209838275): Re-enable this once g3 build rules for gen_snapshot are
+  // working with TSAN.
+#if 0  // defined(USING_THREAD_SANITIZER)
+  if (thread->exit_through_ffi() == Thread::kExitThroughRuntimeCall) {
+    auto tsan_utils = thread->tsan_utils();
+    tsan_utils->exception_pc = program_counter;
+    tsan_utils->exception_sp = stack_pointer;
+    tsan_utils->exception_fp = frame_pointer;
+    longjmp(*(tsan_utils->setjmp_buffer), 1);
+  }
+#endif  // defined(USING_THREAD_SANITIZER)
+
+  // Call a stub to set up the exception object in kExceptionObjectReg,
+  // to set up the stacktrace object in kStackTraceObjectReg, and to
+  // continue execution at the given pc in the given frame.
+  typedef void (*ExcpHandler)(uword, uword, uword, Thread*);
+  ExcpHandler func =
+      reinterpret_cast<ExcpHandler>(StubCode::JumpToFrame().EntryPoint());
+
   func(program_counter, stack_pointer, frame_pointer, thread);
+
 #endif
   UNREACHABLE();
 }
diff --git a/runtime/vm/flag_list.h b/runtime/vm/flag_list.h
index edf42f7..cccfdfb 100644
--- a/runtime/vm/flag_list.h
+++ b/runtime/vm/flag_list.h
@@ -193,6 +193,8 @@
     "needed in the precompiled runtime.")                                      \
   P(show_invisible_frames, bool, false,                                        \
     "Show invisible frames in stack traces.")                                  \
+  P(target_unknown_cpu, bool, false,                                           \
+    "Generate code for a generic CPU, unknown at compile time")                \
   D(trace_cha, bool, false, "Trace CHA operations")                            \
   R(trace_field_guards, false, bool, false, "Trace changes in field's cids.")  \
   D(trace_ic, bool, false, "Trace IC handling")                                \
@@ -246,6 +248,7 @@
   D(support_rr, bool, false, "Support running within RR.")                     \
   P(verify_entry_points, bool, false,                                          \
     "Throw API error on invalid member access throuh native API. See "         \
-    "entry_point_pragma.md")
+    "entry_point_pragma.md")                                                   \
+  C(branch_coverage, false, false, bool, false, "Enable branch coverage")
 
 #endif  // RUNTIME_VM_FLAG_LIST_H_
diff --git a/runtime/vm/heap/scavenger.cc b/runtime/vm/heap/scavenger.cc
index cac516f..8c736b2 100644
--- a/runtime/vm/heap/scavenger.cc
+++ b/runtime/vm/heap/scavenger.cc
@@ -165,21 +165,25 @@
       return;
     }
 
+    // Explicit ifdefs because the compiler does not eliminate the unused
+    // relaxed load.
+#if defined(DEBUG)
     // Validate 'this' is a typed data view.
     const uword view_header = ReadHeaderRelaxed(view);
     ASSERT(!IsForwarding(view_header) || view->IsOldObject());
     ASSERT(IsTypedDataViewClassId(view->GetClassIdMayBeSmi()));
 
-    // Validate that the backing store is not a forwarding word.
+    // Validate that the backing store is not a forwarding word. There is a data
+    // race reader the backing store's header unless there is only one worker.
     TypedDataBasePtr td = view->untag()->typed_data();
     ASSERT(td->IsHeapObject());
-    const uword td_header = ReadHeaderRelaxed(td);
-    ASSERT(!IsForwarding(td_header) || td->IsOldObject());
-
     if (!parallel) {
-      // When there is only one worker, there is no data race.
+      const uword td_header = ReadHeaderRelaxed(td);
+      ASSERT(!IsForwarding(td_header) || td->IsOldObject());
+
       ASSERT_EQUAL(IsExternalTypedDataClassId(td->GetClassId()), is_external);
     }
+#endif
 
     // If we have external typed data we can simply return since the backing
     // store lives in C-heap and will not move.
@@ -188,9 +192,11 @@
     }
 
     // Now we update the inner pointer.
+#if defined(DEBUG)
     if (!parallel) {
       ASSERT(IsTypedDataClassId(td->GetClassId()));
     }
+#endif
     view->untag()->RecomputeDataFieldForInternalTypedData();
   }
 
diff --git a/runtime/vm/image_snapshot.cc b/runtime/vm/image_snapshot.cc
index f77d389..e812345 100644
--- a/runtime/vm/image_snapshot.cc
+++ b/runtime/vm/image_snapshot.cc
@@ -237,6 +237,12 @@
   return offset;
 }
 
+intptr_t ImageWriter::SizeInSnapshotForBytes(intptr_t length) {
+  // We are just going to write it out as a string.
+  return compiler::target::String::InstanceSize(
+      length * OneByteString::kBytesPerElement);
+}
+
 intptr_t ImageWriter::SizeInSnapshot(ObjectPtr raw_object) {
   const classid_t cid = raw_object->GetClassId();
 
@@ -280,13 +286,21 @@
 }
 
 uint32_t ImageWriter::GetDataOffsetFor(ObjectPtr raw_object) {
-  intptr_t snap_size = SizeInSnapshot(raw_object);
-  intptr_t offset = next_data_offset_;
+  const intptr_t snap_size = SizeInSnapshot(raw_object);
+  const intptr_t offset = next_data_offset_;
   next_data_offset_ += snap_size;
   objects_.Add(ObjectData(raw_object));
   return offset;
 }
 
+uint32_t ImageWriter::AddBytesToData(uint8_t* bytes, intptr_t length) {
+  const intptr_t snap_size = SizeInSnapshotForBytes(length);
+  const intptr_t offset = next_data_offset_;
+  next_data_offset_ += snap_size;
+  objects_.Add(ObjectData(bytes, length));
+  return offset;
+}
+
 intptr_t ImageWriter::GetTextObjectCount() const {
   return instructions_.length();
 }
@@ -439,9 +453,24 @@
     // the VM snapshot's text image.
     heap->SetObjectId(data.insns_->ptr(), 0);
   }
-  for (intptr_t i = 0; i < objects_.length(); i++) {
-    ObjectData& data = objects_[i];
-    data.obj_ = &Object::Handle(zone_, data.raw_obj_);
+  for (auto& data : objects_) {
+    if (data.is_object) {
+      data.obj = &Object::Handle(zone_, data.raw_obj);
+    }
+  }
+
+  // Once we have everything handlified we are going to do convert raw bytes
+  // to string objects. String is used for simplicity as a bit container,
+  // can't use TypedData because it has an internal pointer (data_) field.
+  for (auto& data : objects_) {
+    if (!data.is_object) {
+      const auto bytes = data.bytes;
+      data.obj = &Object::Handle(
+          zone_, OneByteString::New(bytes.buf, bytes.length, Heap::kOld));
+      data.is_object = true;
+      String::Cast(*data.obj).Hash();
+      free(bytes.buf);
+    }
   }
 
   // Needs to happen before WriteText, as we add information about the
@@ -484,8 +513,9 @@
 
   // Heap page objects start here.
 
-  for (intptr_t i = 0; i < objects_.length(); i++) {
-    const Object& obj = *objects_[i].obj_;
+  for (auto entry : objects_) {
+    ASSERT(entry.is_object);
+    const Object& obj = *entry.obj;
 #if defined(DART_PRECOMPILER)
     AutoTraceImage(obj, section_start, stream);
 #endif
@@ -498,10 +528,9 @@
     if (obj.IsCompressedStackMaps()) {
       const CompressedStackMaps& map = CompressedStackMaps::Cast(obj);
       const intptr_t payload_size = map.payload_size();
-      stream->WriteTargetWord(map.ptr()->untag()->flags_and_size_);
-      ASSERT_EQUAL(stream->Position() - object_start,
-                   compiler::target::CompressedStackMaps::HeaderSize());
-      stream->WriteBytes(map.ptr()->untag()->data(), payload_size);
+      stream->WriteFixed<uint32_t>(
+          map.ptr()->untag()->payload()->flags_and_size);
+      stream->WriteBytes(map.ptr()->untag()->payload()->data(), payload_size);
     } else if (obj.IsCodeSourceMap()) {
       const CodeSourceMap& map = CodeSourceMap::Cast(obj);
       stream->WriteTargetWord(map.Length());
diff --git a/runtime/vm/image_snapshot.h b/runtime/vm/image_snapshot.h
index 7100d3b..730b861 100644
--- a/runtime/vm/image_snapshot.h
+++ b/runtime/vm/image_snapshot.h
@@ -272,6 +272,8 @@
   int32_t GetTextOffsetFor(InstructionsPtr instructions, CodePtr code);
   uint32_t GetDataOffsetFor(ObjectPtr raw_object);
 
+  uint32_t AddBytesToData(uint8_t* bytes, intptr_t length);
+
   void Write(NonStreamingWriteStream* clustered_stream, bool vm);
   intptr_t data_size() const { return next_data_offset_; }
   intptr_t text_size() const { return next_text_offset_; }
@@ -354,12 +356,20 @@
   };
 
   struct ObjectData {
-    explicit ObjectData(ObjectPtr raw_obj) : raw_obj_(raw_obj) {}
+    explicit ObjectData(ObjectPtr raw_obj)
+        : raw_obj(raw_obj), is_object(true) {}
+    ObjectData(uint8_t* buf, intptr_t length)
+        : bytes({buf, length}), is_object(false) {}
 
     union {
-      ObjectPtr raw_obj_;
-      const Object* obj_;
+      struct {
+        uint8_t* buf;
+        intptr_t length;
+      } bytes;
+      ObjectPtr raw_obj;
+      const Object* obj;
     };
+    bool is_object;
   };
 
   // Methods abstracting out the particulars of the underlying concrete writer.
@@ -447,6 +457,8 @@
   friend class SnapshotTextObjectNamer;  // For InstructionsData.
 
  private:
+  static intptr_t SizeInSnapshotForBytes(intptr_t length);
+
   DISALLOW_COPY_AND_ASSIGN(ImageWriter);
 };
 
diff --git a/runtime/vm/isolate.cc b/runtime/vm/isolate.cc
index 11a73d3..a48a622 100644
--- a/runtime/vm/isolate.cc
+++ b/runtime/vm/isolate.cc
@@ -2400,6 +2400,18 @@
                                                    std::memory_order_release));
 }
 
+class StreamableSampleFilter : public SampleFilter {
+ public:
+  explicit StreamableSampleFilter(Dart_Port port)
+      : SampleFilter(port, kNoTaskFilter, -1, -1) {}
+
+  bool FilterSample(Sample* sample) override {
+    const UserTag& tag =
+        UserTag::Handle(UserTag::FindTagById(sample->user_tag()));
+    return tag.streamable();
+  }
+};
+
 void Isolate::ProcessFreeSampleBlocks(Thread* thread) {
   SampleBlock* head = free_block_list_.exchange(nullptr);
   if (head == nullptr) {
@@ -2426,11 +2438,14 @@
     SampleBlockListProcessor buffer(head);
     StackZone zone(thread);
     HandleScope handle_scope(thread);
+    StreamableSampleFilter filter(main_port());
     Profile profile;
-    profile.Build(thread, nullptr, &buffer);
-    ServiceEvent event(this, ServiceEvent::kCpuSamples);
-    event.set_cpu_profile(&profile);
-    Service::HandleEvent(&event);
+    profile.Build(thread, &filter, &buffer);
+    if (profile.sample_count() > 0) {
+      ServiceEvent event(this, ServiceEvent::kCpuSamples);
+      event.set_cpu_profile(&profile);
+      Service::HandleEvent(&event);
+    }
   }
 
   do {
@@ -3369,7 +3384,8 @@
 // done atomically.
 void Isolate::RegisterServiceExtensionHandler(const String& name,
                                               const Instance& closure) {
-  if (Isolate::IsSystemIsolate(this)) {
+  // Don't allow for service extensions to be registered for internal isolates.
+  if (Isolate::IsVMInternalIsolate(this)) {
     return;
   }
   GrowableObjectArray& handlers =
@@ -3573,6 +3589,11 @@
   return group->source()->flags.is_system_isolate;
 }
 
+bool Isolate::IsVMInternalIsolate(const Isolate* isolate) {
+  return isolate->is_kernel_isolate() || isolate->is_service_isolate() ||
+         (Dart::vm_isolate() == isolate);
+}
+
 void Isolate::KillLocked(LibMsgId msg_id) {
   Dart_CObject kill_msg;
   Dart_CObject* list_values[4];
diff --git a/runtime/vm/isolate.h b/runtime/vm/isolate.h
index 2c531f0..1048e4e 100644
--- a/runtime/vm/isolate.h
+++ b/runtime/vm/isolate.h
@@ -163,7 +163,9 @@
     load_vmservice_library, false)                                             \
   V(NONPRODUCT, use_osr, UseOsr, use_osr, FLAG_use_osr)                        \
   V(NONPRODUCT, snapshot_is_dontneed_safe, SnapshotIsDontNeedSafe,             \
-    snapshot_is_dontneed_safe, false)
+    snapshot_is_dontneed_safe, false)                                          \
+  V(NONPRODUCT, branch_coverage, BranchCoverage, branch_coverage,              \
+    FLAG_branch_coverage)
 
 #define BOOL_ISOLATE_FLAG_LIST_DEFAULT_GETTER(V)                               \
   V(PRODUCT, copy_parent_code, CopyParentCode, copy_parent_code, false)        \
@@ -796,7 +798,8 @@
   V(Obfuscate)                                                                 \
   V(UseFieldGuards)                                                            \
   V(UseOsr)                                                                    \
-  V(SnapshotIsDontNeedSafe)
+  V(SnapshotIsDontNeedSafe)                                                    \
+  V(BranchCoverage)
 
   // Isolate group specific flags.
   enum FlagBits {
@@ -1401,6 +1404,7 @@
   static bool IsSystemIsolate(const Isolate* isolate) {
     return IsolateGroup::IsSystemIsolateGroup(isolate->group());
   }
+  static bool IsVMInternalIsolate(const Isolate* isolate);
 
   HandlerInfoCache* handler_info_cache() { return &handler_info_cache_; }
 
diff --git a/runtime/vm/json_stream.cc b/runtime/vm/json_stream.cc
index 01b6c5f..dfac508 100644
--- a/runtime/vm/json_stream.cc
+++ b/runtime/vm/json_stream.cc
@@ -164,16 +164,16 @@
     JSONObject data(&jsobj, "data");
     PrintRequest(&data, this);
     if (details_format != NULL) {
-      va_list args;
-      va_start(args, details_format);
-      intptr_t len = Utils::VSNPrint(NULL, 0, details_format, args);
-      va_end(args);
+      va_list measure_args;
+      va_start(measure_args, details_format);
+      intptr_t len = Utils::VSNPrint(NULL, 0, details_format, measure_args);
+      va_end(measure_args);
 
       char* buffer = Thread::Current()->zone()->Alloc<char>(len + 1);
-      va_list args2;
-      va_start(args2, details_format);
-      Utils::VSNPrint(buffer, (len + 1), details_format, args2);
-      va_end(args2);
+      va_list print_args;
+      va_start(print_args, details_format);
+      Utils::VSNPrint(buffer, (len + 1), details_format, print_args);
+      va_end(print_args);
       data.AddProperty("details", buffer);
     }
   }
diff --git a/runtime/vm/kernel_binary.h b/runtime/vm/kernel_binary.h
index 46d20ec..891a2b7 100644
--- a/runtime/vm/kernel_binary.h
+++ b/runtime/vm/kernel_binary.h
@@ -20,8 +20,8 @@
 static const uint32_t kMagicProgramFile = 0x90ABCDEFu;
 
 // Both version numbers are inclusive.
-static const uint32_t kMinSupportedKernelFormatVersion = 74;
-static const uint32_t kMaxSupportedKernelFormatVersion = 74;
+static const uint32_t kMinSupportedKernelFormatVersion = 75;
+static const uint32_t kMaxSupportedKernelFormatVersion = 75;
 
 // Keep in sync with package:kernel/lib/binary/tag.dart
 #define KERNEL_TAG_LIST(V)                                                     \
diff --git a/runtime/vm/kernel_loader.cc b/runtime/vm/kernel_loader.cc
index 6236cf3..39689f6 100644
--- a/runtime/vm/kernel_loader.cc
+++ b/runtime/vm/kernel_loader.cc
@@ -1588,6 +1588,25 @@
       fields_[0]->set_is_nullable(true);
     }
 
+    // Check that subclasses of AbiSpecificInteger have a mapping for the
+    // current ABI.
+    //
+    // TODO(https://github.com/dart-lang/language/issues/1889): If we make
+    // kernel know about the target platform, we can move this check to the
+    // frontend.
+    const auto& super_class = Class::Handle(Z, klass.SuperClass());
+    if (!super_class.IsNull() &&
+        super_class.UserVisibleName() == Symbols::AbiSpecificInteger().ptr() &&
+        Library::Handle(Z, super_class.library()).url() ==
+            Symbols::DartFfi().ptr()) {
+      const char* error = nullptr;
+      compiler::ffi::NativeType::FromAbstractType(
+          Z, AbstractType::Handle(Z, klass.DeclarationType()), &error);
+      if (error != nullptr) {
+        H.ReportError("%s", error);
+      }
+    }
+
     // Due to ReadVMAnnotations(), the klass may have been loaded at this point
     // (loading the class while evaluating annotations).
     if (klass.is_loaded()) {
@@ -1952,6 +1971,7 @@
   }
   function.set_kernel_offset(procedure_offset);
   function.set_is_extension_member(is_extension_member);
+  function.set_is_redirecting_factory(procedure_helper.IsRedirectingFactory());
   if ((library.is_dart_scheme() &&
        H.IsPrivate(procedure_helper.canonical_name_)) ||
       (function.is_static() && (library.ptr() == Library::InternalLibrary()))) {
diff --git a/runtime/vm/malloc_hooks_tcmalloc.cc b/runtime/vm/malloc_hooks_tcmalloc.cc
index 438e477..3dc3639 100644
--- a/runtime/vm/malloc_hooks_tcmalloc.cc
+++ b/runtime/vm/malloc_hooks_tcmalloc.cc
@@ -341,7 +341,11 @@
 bool MallocHooks::GetStats(intptr_t* used,
                            intptr_t* capacity,
                            const char** implementation) {
+#if defined(DART_USE_MALLINFO2)
+  struct mallinfo2 info = mallinfo2();
+#else
   struct mallinfo info = mallinfo();
+#endif  // defined(DART_USE_MALLINFO2)
   *used = info.uordblks;
   *capacity = *used + info.fordblks;
   *implementation = "tcmalloc";
diff --git a/runtime/vm/malloc_hooks_unsupported.cc b/runtime/vm/malloc_hooks_unsupported.cc
index 9650cff..5b666d1 100644
--- a/runtime/vm/malloc_hooks_unsupported.cc
+++ b/runtime/vm/malloc_hooks_unsupported.cc
@@ -70,7 +70,11 @@
   }
 #endif
 #if defined(DART_HOST_OS_LINUX) || defined(DART_HOST_OS_ANDROID)
+#if defined(DART_USE_MALLINFO2)
+  struct mallinfo2 info = mallinfo2();
+#else
   struct mallinfo info = mallinfo();
+#endif  // defined(DART_USE_MALLINFO2)
   *used = info.uordblks;
   *capacity = *used + info.fordblks;
   *implementation = "unknown";
diff --git a/runtime/vm/message_snapshot.cc b/runtime/vm/message_snapshot.cc
index 4733db0..afc2bc3 100644
--- a/runtime/vm/message_snapshot.cc
+++ b/runtime/vm/message_snapshot.cc
@@ -2133,6 +2133,19 @@
           reinterpret_cast<uint8_t*>(finalizable_data.data), length));
     }
   }
+
+  void ReadNodesApi(ApiMessageDeserializer* d) {
+    intptr_t count = d->ReadUnsigned();
+    for (intptr_t i = 0; i < count; i++) {
+      Dart_CObject* data = d->Allocate(Dart_CObject_kTypedData);
+      data->value.as_typed_data.length = d->ReadUnsigned();
+      data->value.as_typed_data.type = Dart_TypedData_kUint8;
+      FinalizableData finalizable_data = d->finalizable_data()->Get();
+      data->value.as_typed_data.values =
+          reinterpret_cast<uint8_t*>(finalizable_data.data);
+      d->AssignRef(data);
+    }
+  }
 };
 
 class Simd128MessageSerializationCluster : public MessageSerializationCluster {
diff --git a/runtime/vm/object.cc b/runtime/vm/object.cc
index df10c58..6fd3ef4 100644
--- a/runtime/vm/object.cc
+++ b/runtime/vm/object.cc
@@ -1036,7 +1036,7 @@
         empty_compressed_stackmaps_,
         static_cast<CompressedStackMapsPtr>(address + kHeapObjectTag));
     empty_compressed_stackmaps_->StoreNonPointer(
-        &empty_compressed_stackmaps_->untag()->flags_and_size_, 0);
+        &empty_compressed_stackmaps_->untag()->payload()->flags_and_size, 0);
     empty_compressed_stackmaps_->SetCanonical();
   }
 
@@ -1344,8 +1344,13 @@
         // Some classes have identity hash codes that depend on their contents,
         // not per object.
         ASSERT(!obj->IsStringInstance());
-        if (!obj->IsMint() && !obj->IsDouble() && !obj->IsRawNull() &&
-            !obj->IsBool()) {
+        if (obj == Object::null()) {
+          Object::SetCachedHashIfNotSet(obj, kNullIdentityHash);
+        } else if (obj == Object::bool_true().ptr()) {
+          Object::SetCachedHashIfNotSet(obj, kTrueIdentityHash);
+        } else if (obj == Object::bool_false().ptr()) {
+          Object::SetCachedHashIfNotSet(obj, kFalseIdentityHash);
+        } else if (!obj->IsMint() && !obj->IsDouble()) {
           counter_ += 2011;  // The year Dart was announced and a prime.
           counter_ &= 0x3fffffff;
           if (counter_ == 0) counter_++;
@@ -7562,15 +7567,20 @@
   if (IsFfiTypeClassId(type.type_class_id())) {
     return false;
   }
-  // TODO(http://dartbug.com/42563): Implement AbiSpecificInt.
-#ifdef DEBUG
   const auto& cls = Class::Handle(zone, type.type_class());
   const auto& superClass = Class::Handle(zone, cls.SuperClass());
+  const bool is_abi_specific_int =
+      String::Handle(zone, superClass.UserVisibleName())
+          .Equals(Symbols::AbiSpecificInteger());
+  if (is_abi_specific_int) {
+    return false;
+  }
+#ifdef DEBUG
   const bool is_struct = String::Handle(zone, superClass.UserVisibleName())
                              .Equals(Symbols::Struct());
   const bool is_union = String::Handle(zone, superClass.UserVisibleName())
                             .Equals(Symbols::Union());
-  RELEASE_ASSERT(is_struct || is_union);
+  ASSERT(is_struct || is_union);
 #endif
   return true;
 }
@@ -9522,15 +9532,6 @@
   return target.ptr();
 }
 
-intptr_t Function::ComputeClosureHash() const {
-  ASSERT(IsClosureFunction());
-  const Class& cls = Class::Handle(Owner());
-  uintptr_t result = String::Handle(name()).Hash();
-  result += String::Handle(InternalSignature()).Hash();
-  result += String::Handle(cls.Name()).Hash();
-  return result;
-}
-
 void FunctionType::Print(NameVisibility name_visibility,
                          BaseTextBuffer* printer) const {
   if (IsNull()) {
@@ -14573,21 +14574,27 @@
   StoreNonPointer(&untag()->end_pc_, value);
 }
 
-void InstructionsTable::set_descriptors(const Array& value) const {
-  untag()->set_descriptors(value.ptr());
+void InstructionsTable::set_code_objects(const Array& value) const {
+  untag()->set_code_objects(value.ptr());
+}
+
+void InstructionsTable::set_rodata(uword value) const {
+  StoreNonPointer(
+      &untag()->rodata_,
+      reinterpret_cast<const UntaggedInstructionsTable::Data*>(value));
 }
 
 InstructionsTablePtr InstructionsTable::New(intptr_t length,
                                             uword start_pc,
-                                            uword end_pc) {
+                                            uword end_pc,
+                                            uword rodata) {
   ASSERT(Object::instructions_table_class() != Class::null());
   ASSERT(length >= 0);
   ASSERT(start_pc <= end_pc);
-  ASSERT(Utils::IsAligned(start_pc, kPayloadAlignment));
   Thread* thread = Thread::Current();
   InstructionsTable& result = InstructionsTable::Handle(thread->zone());
   {
-    uword size = InstructionsTable::InstanceSize(length);
+    uword size = InstructionsTable::InstanceSize();
     ObjectPtr raw =
         Object::Allocate(InstructionsTable::kClassId, size, Heap::kOld,
                          InstructionsTable::ContainsCompressedPointers());
@@ -14595,31 +14602,20 @@
     result ^= raw;
     result.set_length(length);
   }
-  const Array& descriptors =
+  const Array& code_objects =
       (length == 0) ? Object::empty_array()
                     : Array::Handle(Array::New(length, Heap::kOld));
-  result.set_descriptors(descriptors);
+  result.set_code_objects(code_objects);
   result.set_start_pc(start_pc);
   result.set_end_pc(end_pc);
+  result.set_rodata(rodata);
   return result.ptr();
 }
 
-void InstructionsTable::SetEntryAt(intptr_t index,
-                                   uword payload_start,
-                                   bool has_monomorphic_entrypoint,
-                                   ObjectPtr descriptor) const {
-  ASSERT((0 <= index) && (index < length()));
-  ASSERT(ContainsPc(payload_start));
-  ASSERT(Utils::IsAligned(payload_start, kPayloadAlignment));
-
-  const uint32_t pc_offset = ConvertPcToOffset(payload_start);
-  ASSERT((index == 0) || (PcOffsetAt(index - 1) <= pc_offset));
-  ASSERT((pc_offset & kHasMonomorphicEntrypointFlag) == 0);
-
-  untag()->data()[index] =
-      pc_offset |
-      (has_monomorphic_entrypoint ? kHasMonomorphicEntrypointFlag : 0);
-  descriptors()->untag()->set_element(index, descriptor);
+void InstructionsTable::SetCodeAt(intptr_t index, CodePtr code) const {
+  ASSERT((0 <= index) &&
+         (index < Smi::Value(code_objects()->untag()->length())));
+  code_objects()->untag()->set_element(index, code);
 }
 
 bool InstructionsTable::ContainsPc(InstructionsTablePtr table, uword pc) {
@@ -14636,21 +14632,25 @@
   return pc_offset;
 }
 
-intptr_t InstructionsTable::FindEntry(InstructionsTablePtr table, uword pc) {
+intptr_t InstructionsTable::FindEntry(InstructionsTablePtr table,
+                                      uword pc,
+                                      intptr_t start_index /* = 0 */) {
   // This can run in the middle of GC and must not allocate handles.
   NoSafepointScope no_safepoint;
   if (!InstructionsTable::ContainsPc(table, pc)) return -1;
   const uint32_t pc_offset = InstructionsTable::ConvertPcToOffset(table, pc);
-  intptr_t lo = 0;
-  intptr_t hi = InstructionsTable::length(table) - 1;
+
+  const auto rodata = table.untag()->rodata_;
+  const auto entries = rodata->entries();
+  intptr_t lo = start_index;
+  intptr_t hi = rodata->length - 1;
   while (lo <= hi) {
     intptr_t mid = (hi - lo + 1) / 2 + lo;
     ASSERT(mid >= lo);
     ASSERT(mid <= hi);
-    if (pc_offset < InstructionsTable::PcOffsetAt(table, mid)) {
+    if (pc_offset < entries[mid].pc_offset) {
       hi = mid - 1;
-    } else if ((mid != hi) &&
-               (pc_offset >= InstructionsTable::PcOffsetAt(table, mid + 1))) {
+    } else if ((mid != hi) && (pc_offset >= entries[mid + 1].pc_offset)) {
       lo = mid + 1;
     } else {
       return mid;
@@ -14659,22 +14659,66 @@
   return -1;
 }
 
-ObjectPtr InstructionsTable::DescriptorAt(InstructionsTablePtr table,
-                                          intptr_t index) {
-  ASSERT((0 <= index) && (index < InstructionsTable::length(table)));
-  return table->untag()->descriptors()->untag()->element(index);
+const UntaggedCompressedStackMaps::Payload*
+InstructionsTable::GetCanonicalStackMap(InstructionsTablePtr table) {
+  const auto rodata = table.untag()->rodata_;
+  return rodata->canonical_stack_map_entries_offset != 0
+             ? rodata->StackMapAt(rodata->canonical_stack_map_entries_offset)
+             : nullptr;
 }
 
-uword InstructionsTable::PayloadStartAt(InstructionsTablePtr table,
-                                        intptr_t index) {
-  return InstructionsTable::start_pc(table) +
-         InstructionsTable::PcOffsetAt(table, index);
+const UntaggedCompressedStackMaps::Payload* InstructionsTable::FindStackMap(
+    InstructionsTablePtr table,
+    uword pc,
+    uword* start_pc) {
+  // This can run in the middle of GC and must not allocate handles.
+  NoSafepointScope no_safepoint;
+  const intptr_t idx = FindEntry(table, pc);
+  if (idx != -1) {
+    const auto rodata = table.untag()->rodata_;
+    const auto entries = rodata->entries();
+    *start_pc = InstructionsTable::start_pc(table) + entries[idx].pc_offset;
+    return rodata->StackMapAt(entries[idx].stack_map_offset);
+  }
+  return 0;
 }
 
-uword InstructionsTable::EntryPointAt(intptr_t index) const {
-  return PayloadStartAt(index) + (HasMonomorphicEntryPointAt(index)
-                                      ? Instructions::kPolymorphicEntryOffsetAOT
-                                      : 0);
+CodePtr InstructionsTable::FindCode(InstructionsTablePtr table, uword pc) {
+  // This can run in the middle of GC and must not allocate handles.
+  NoSafepointScope no_safepoint;
+  if (!InstructionsTable::ContainsPc(table, pc)) return Code::null();
+
+  const auto rodata = table.untag()->rodata_;
+
+  const auto pc_offset = InstructionsTable::ConvertPcToOffset(table, pc);
+
+  if (pc_offset <= rodata->entries()[rodata->first_entry_with_code].pc_offset) {
+    return StubCode::UnknownDartCode().ptr();
+  }
+
+  const auto idx =
+      FindEntry(table, pc, table.untag()->rodata_->first_entry_with_code);
+  if (idx != -1) {
+    const intptr_t code_index = idx - rodata->first_entry_with_code;
+    ASSERT(code_index >= 0);
+    ASSERT(code_index <
+           Smi::Value(table.untag()->code_objects()->untag()->length()));
+    ObjectPtr result =
+        table.untag()->code_objects()->untag()->element(code_index);
+    ASSERT(result->IsCode());
+    // Note: can't use Code::RawCast(...) here because it allocates handles
+    // in DEBUG mode.
+    return static_cast<CodePtr>(result);
+  }
+
+  return Code::null();
+}
+
+uword InstructionsTable::EntryPointAt(intptr_t code_index) const {
+  ASSERT(0 <= code_index);
+  ASSERT(code_index < static_cast<intptr_t>(rodata()->length));
+  return InstructionsTable::start_pc(this->ptr()) +
+         rodata()->entries()[code_index].pc_offset;
 }
 
 const char* InstructionsTable::ToCString() const {
@@ -14970,7 +15014,7 @@
 
 uword CompressedStackMaps::Hash() const {
   NoSafepointScope scope;
-  uint8_t* data = UnsafeMutableNonPointer(&untag()->data()[0]);
+  uint8_t* data = UnsafeMutableNonPointer(&untag()->payload()->data()[0]);
   uint8_t* end = data + payload_size();
   uint32_t hash = payload_size();
   for (uint8_t* cursor = data; cursor < end; cursor++) {
@@ -14979,140 +15023,11 @@
   return FinalizeHash(hash, kHashBits);
 }
 
-CompressedStackMaps::Iterator::Iterator(const CompressedStackMaps& maps,
-                                        const CompressedStackMaps& global_table)
-    : maps_(maps),
-      bits_container_(maps_.UsesGlobalTable() ? global_table : maps_) {
-  ASSERT(!maps_.IsNull());
-  ASSERT(!bits_container_.IsNull());
-  ASSERT(!maps_.IsGlobalTable());
-  ASSERT(!maps_.UsesGlobalTable() || bits_container_.IsGlobalTable());
-}
-
-CompressedStackMaps::Iterator::Iterator(Thread* thread,
-                                        const CompressedStackMaps& maps)
-    : CompressedStackMaps::Iterator(
-          maps,
-          // Only look up the global table if the map will end up using it.
-          maps.UsesGlobalTable() ? CompressedStackMaps::Handle(
-                                       thread->zone(),
-                                       thread->isolate_group()
-                                           ->object_store()
-                                           ->canonicalized_stack_map_entries())
-                                 : Object::null_compressed_stackmaps()) {}
-
-CompressedStackMaps::Iterator::Iterator(const CompressedStackMaps::Iterator& it)
-    : maps_(it.maps_),
-      bits_container_(it.bits_container_),
-      next_offset_(it.next_offset_),
-      current_pc_offset_(it.current_pc_offset_),
-      current_global_table_offset_(it.current_global_table_offset_),
-      current_spill_slot_bit_count_(it.current_spill_slot_bit_count_),
-      current_non_spill_slot_bit_count_(it.current_spill_slot_bit_count_),
-      current_bits_offset_(it.current_bits_offset_) {}
-
-bool CompressedStackMaps::Iterator::MoveNext() {
-  if (next_offset_ >= maps_.payload_size()) {
-    return false;
-  }
-
-  NoSafepointScope scope;
-  ReadStream stream(maps_.untag()->data(), maps_.payload_size(), next_offset_);
-
-  auto const pc_delta = stream.ReadLEB128();
-  ASSERT(pc_delta <= (kMaxUint32 - current_pc_offset_));
-  current_pc_offset_ += pc_delta;
-
-  // Table-using CSMs have a table offset after the PC offset delta, whereas
-  // the post-delta part of inlined entries has the same information as
-  // global table entries.
-  if (maps_.UsesGlobalTable()) {
-    current_global_table_offset_ = stream.ReadLEB128();
-    ASSERT(current_global_table_offset_ < bits_container_.payload_size());
-
-    // Since generally we only use entries in the GC and the GC only needs
-    // the rest of the entry information if the PC offset matches, we lazily
-    // load and cache the information stored in the global object when it is
-    // actually requested.
-    current_spill_slot_bit_count_ = -1;
-    current_non_spill_slot_bit_count_ = -1;
-    current_bits_offset_ = -1;
-
-    next_offset_ = stream.Position();
-  } else {
-    current_spill_slot_bit_count_ = stream.ReadLEB128();
-    ASSERT(current_spill_slot_bit_count_ >= 0);
-
-    current_non_spill_slot_bit_count_ = stream.ReadLEB128();
-    ASSERT(current_non_spill_slot_bit_count_ >= 0);
-
-    const auto stackmap_bits =
-        current_spill_slot_bit_count_ + current_non_spill_slot_bit_count_;
-    const uintptr_t stackmap_size =
-        Utils::RoundUp(stackmap_bits, kBitsPerByte) >> kBitsPerByteLog2;
-    ASSERT(stackmap_size <= (maps_.payload_size() - stream.Position()));
-
-    current_bits_offset_ = stream.Position();
-    next_offset_ = current_bits_offset_ + stackmap_size;
-  }
-
-  return true;
-}
-
-intptr_t CompressedStackMaps::Iterator::Length() const {
-  EnsureFullyLoadedEntry();
-  return current_spill_slot_bit_count_ + current_non_spill_slot_bit_count_;
-}
-intptr_t CompressedStackMaps::Iterator::SpillSlotBitCount() const {
-  EnsureFullyLoadedEntry();
-  return current_spill_slot_bit_count_;
-}
-
-bool CompressedStackMaps::Iterator::IsObject(intptr_t bit_index) const {
-  EnsureFullyLoadedEntry();
-  ASSERT(bit_index >= 0 && bit_index < Length());
-  const intptr_t byte_index = bit_index >> kBitsPerByteLog2;
-  const intptr_t bit_remainder = bit_index & (kBitsPerByte - 1);
-  uint8_t byte_mask = 1U << bit_remainder;
-  const intptr_t byte_offset = current_bits_offset_ + byte_index;
-  NoSafepointScope scope;
-  return (bits_container_.untag()->data()[byte_offset] & byte_mask) != 0;
-}
-
-void CompressedStackMaps::Iterator::LazyLoadGlobalTableEntry() const {
-  ASSERT(maps_.UsesGlobalTable());
-  ASSERT(HasLoadedEntry());
-  ASSERT(current_global_table_offset_ < bits_container_.payload_size());
-
-  NoSafepointScope scope;
-  ReadStream stream(bits_container_.untag()->data(),
-                    bits_container_.payload_size(),
-                    current_global_table_offset_);
-
-  current_spill_slot_bit_count_ = stream.ReadLEB128();
-  ASSERT(current_spill_slot_bit_count_ >= 0);
-
-  current_non_spill_slot_bit_count_ = stream.ReadLEB128();
-  ASSERT(current_non_spill_slot_bit_count_ >= 0);
-
-  const auto stackmap_bits = Length();
-  const uintptr_t stackmap_size =
-      Utils::RoundUp(stackmap_bits, kBitsPerByte) >> kBitsPerByteLog2;
-  ASSERT(stackmap_size <= (bits_container_.payload_size() - stream.Position()));
-
-  current_bits_offset_ = stream.Position();
-}
-
-void CompressedStackMaps::Iterator::WriteToBuffer(BaseTextBuffer* buffer,
-                                                  const char* separator) const {
-  CompressedStackMaps::Iterator it(*this);
-  // If we haven't loaded an entry yet, do so (but don't skip the current
-  // one if we have!)
-  if (!it.HasLoadedEntry()) {
-    if (!it.MoveNext()) return;
-  }
+void CompressedStackMaps::WriteToBuffer(BaseTextBuffer* buffer,
+                                        const char* separator) const {
+  auto it = iterator(Thread::Current());
   bool first_entry = true;
-  do {
+  while (it.MoveNext()) {
     if (!first_entry) {
       buffer->AddString(separator);
     }
@@ -15121,7 +15036,16 @@
       buffer->AddString(it.IsObject(i) ? "1" : "0");
     }
     first_entry = false;
-  } while (it.MoveNext());
+  }
+}
+
+CompressedStackMaps::Iterator<CompressedStackMaps>
+CompressedStackMaps::iterator(Thread* thread) const {
+  return Iterator<CompressedStackMaps>(
+      *this, CompressedStackMaps::Handle(
+                 thread->zone(), thread->isolate_group()
+                                     ->object_store()
+                                     ->canonicalized_stack_map_entries()));
 }
 
 CompressedStackMapsPtr CompressedStackMaps::New(const void* payload,
@@ -15151,12 +15075,13 @@
     NoSafepointScope no_safepoint;
     result ^= raw;
     result.StoreNonPointer(
-        &result.untag()->flags_and_size_,
+        &result.untag()->payload()->flags_and_size,
         UntaggedCompressedStackMaps::GlobalTableBit::encode(is_global_table) |
             UntaggedCompressedStackMaps::UsesTableBit::encode(
                 uses_global_table) |
             UntaggedCompressedStackMaps::SizeField::encode(size));
-    auto cursor = result.UnsafeMutableNonPointer(result.untag()->data());
+    auto cursor =
+        result.UnsafeMutableNonPointer(result.untag()->payload()->data());
     memcpy(cursor, payload, size);  // NOLINT
   }
 
@@ -15171,10 +15096,9 @@
     return "CompressedStackMaps()";
   }
   auto const t = Thread::Current();
-  CompressedStackMaps::Iterator it(t, *this);
   ZoneTextBuffer buffer(t->zone(), 100);
   buffer.AddString("CompressedStackMaps(");
-  it.WriteToBuffer(&buffer, ", ");
+  WriteToBuffer(&buffer, ", ");
   buffer.AddString(")");
   return buffer.buffer();
 }
@@ -18995,8 +18919,45 @@
   return DartLibraryCalls::HashCode(*this);
 }
 
-ObjectPtr Instance::IdentityHashCode() const {
-  return DartLibraryCalls::IdentityHashCode(*this);
+// Keep in sync with AsmIntrinsifier::Object_getHash.
+IntegerPtr Instance::IdentityHashCode(Thread* thread) const {
+  if (IsInteger()) return Integer::Cast(*this).ptr();
+
+#if defined(HASH_IN_OBJECT_HEADER)
+  intptr_t hash = Object::GetCachedHash(ptr());
+#else
+  intptr_t hash = thread->heap()->GetHash(ptr());
+#endif
+  if (hash == 0) {
+    if (IsNull()) {
+      hash = kNullIdentityHash;
+    } else if (IsBool()) {
+      hash = Bool::Cast(*this).value() ? kTrueIdentityHash : kFalseIdentityHash;
+    } else if (IsDouble()) {
+      double val = Double::Cast(*this).value();
+      if ((val >= kMinInt64RepresentableAsDouble) &&
+          (val <= kMaxInt64RepresentableAsDouble)) {
+        int64_t ival = static_cast<int64_t>(val);
+        if (static_cast<double>(ival) == val) {
+          return Integer::New(ival);
+        }
+      }
+
+      uint64_t uval = bit_cast<uint64_t>(val);
+      hash = ((uval >> 32) ^ (uval)) & kSmiMax;
+    } else {
+      do {
+        hash = thread->random()->NextUInt32() & 0x3FFFFFFF;
+      } while (hash == 0);
+    }
+
+#if defined(HASH_IN_OBJECT_HEADER)
+    hash = Object::SetCachedHashIfNotSet(ptr(), hash);
+#else
+    hash = thread->heap()->SetHashIfNotSet(ptr(), hash);
+#endif
+  }
+  return Smi::New(hash);
 }
 
 bool Instance::CanonicalizeEquals(const Instance& other) const {
@@ -19058,7 +19019,7 @@
 
 uint32_t Instance::CanonicalizeHash() const {
   if (GetClassId() == kNullCid) {
-    return 2011;  // Matches null_patch.dart.
+    return kNullIdentityHash;
   }
   Thread* thread = Thread::Current();
   uint32_t hash = thread->heap()->GetCanonicalHash(ptr());
@@ -25457,7 +25418,7 @@
     // Implicit instance closures are not unique, so combine function's hash
     // code, delayed type arguments hash code (if generic), and identityHashCode
     // of cached receiver.
-    result = static_cast<uint32_t>(func.ComputeClosureHash());
+    result = static_cast<uint32_t>(func.Hash());
     if (func.IsGeneric()) {
       const TypeArguments& delayed_type_args =
           TypeArguments::Handle(zone, delayed_type_arguments());
@@ -25466,23 +25427,15 @@
     const Context& context = Context::Handle(zone, this->context());
     const Instance& receiver =
         Instance::Handle(zone, Instance::RawCast(context.At(0)));
-    const Object& receiverHash =
-        Object::Handle(zone, receiver.IdentityHashCode());
-    if (receiverHash.IsError()) {
-      Exceptions::PropagateError(Error::Cast(receiverHash));
-      UNREACHABLE();
-    }
-    result = CombineHashes(
-        result, Integer::Cast(receiverHash).AsTruncatedUint32Value());
+    const Integer& receiverHash =
+        Integer::Handle(zone, receiver.IdentityHashCode(thread));
+    result = CombineHashes(result, receiverHash.AsTruncatedUint32Value());
   } else {
     // Explicit closures and implicit static closures are unique,
     // so identityHashCode of closure object is good enough.
-    const Object& identityHash = Object::Handle(zone, this->IdentityHashCode());
-    if (identityHash.IsError()) {
-      Exceptions::PropagateError(Error::Cast(identityHash));
-      UNREACHABLE();
-    }
-    result = Integer::Cast(identityHash).AsTruncatedUint32Value();
+    const Integer& identityHash =
+        Integer::Handle(zone, this->IdentityHashCode(thread));
+    result = identityHash.AsTruncatedUint32Value();
   }
   return FinalizeHash(result, String::kHashBits);
 }
@@ -26231,6 +26184,7 @@
     result ^= raw;
   }
   result.set_label(label);
+  result.set_streamable(UserTags::IsTagNameStreamable(label.ToCString()));
   AddTagToIsolate(thread, result);
   return result.ptr();
 }
@@ -26252,10 +26206,13 @@
   return result.ptr();
 }
 
-UserTagPtr UserTag::FindTagInIsolate(Thread* thread, const String& label) {
-  Isolate* isolate = thread->isolate();
+UserTagPtr UserTag::FindTagInIsolate(Isolate* isolate,
+                                     Thread* thread,
+                                     const String& label) {
   Zone* zone = thread->zone();
-  ASSERT(isolate->tag_table() != GrowableObjectArray::null());
+  if (isolate->tag_table() == GrowableObjectArray::null()) {
+    return UserTag::null();
+  }
   const GrowableObjectArray& tag_table =
       GrowableObjectArray::Handle(zone, isolate->tag_table());
   UserTag& other = UserTag::Handle(zone);
@@ -26272,6 +26229,11 @@
   return UserTag::null();
 }
 
+UserTagPtr UserTag::FindTagInIsolate(Thread* thread, const String& label) {
+  Isolate* isolate = thread->isolate();
+  return FindTagInIsolate(isolate, thread, label);
+}
+
 void UserTag::AddTagToIsolate(Thread* thread, const UserTag& tag) {
   Isolate* isolate = thread->isolate();
   Zone* zone = thread->zone();
diff --git a/runtime/vm/object.h b/runtime/vm/object.h
index d1fe844..67a9e89 100644
--- a/runtime/vm/object.h
+++ b/runtime/vm/object.h
@@ -2947,8 +2947,6 @@
   // invalid (e.g., mismatched argument shapes after a reload).
   FunctionPtr ImplicitClosureTarget(Zone* zone) const;
 
-  intptr_t ComputeClosureHash() const;
-
   FunctionPtr ForwardingTarget() const;
   void SetForwardingTarget(const Function& target) const;
 
@@ -3800,7 +3798,8 @@
   V(PolymorphicTarget, is_polymorphic_target)                                  \
   V(HasPragma, has_pragma)                                                     \
   V(IsSynthetic, is_synthetic)                                                 \
-  V(IsExtensionMember, is_extension_member)
+  V(IsExtensionMember, is_extension_member)                                    \
+  V(IsRedirectingFactory, is_redirecting_factory)
 // Bit that is updated after function is constructed, has to be updated in
 // concurrent-safe manner.
 #define FOR_EACH_FUNCTION_VOLATILE_KIND_BIT(V) V(Inlinable, is_inlinable)
@@ -5591,58 +5590,29 @@
 // Used in AOT in bare instructions mode.
 class InstructionsTable : public Object {
  public:
-  static const intptr_t kBytesPerElement = sizeof(uint32_t);
-  static const intptr_t kMaxElements = kIntptrMax / kBytesPerElement;
-
-  static const uint32_t kHasMonomorphicEntrypointFlag = 0x1;
-  static const uint32_t kPayloadAlignment = Instructions::kBarePayloadAlignment;
-  static const uint32_t kPayloadMask = ~(kPayloadAlignment - 1);
-  COMPILE_ASSERT((kPayloadMask & kHasMonomorphicEntrypointFlag) == 0);
-
-  struct ArrayTraits {
-    static intptr_t elements_start_offset() {
-      return sizeof(UntaggedInstructionsTable);
-    }
-    static constexpr intptr_t kElementSize = kBytesPerElement;
-  };
-
-  static intptr_t InstanceSize() {
-    ASSERT_EQUAL(sizeof(UntaggedInstructionsTable),
-                 OFFSET_OF_RETURNED_VALUE(UntaggedInstructionsTable, data));
-    return 0;
-  }
-  static intptr_t InstanceSize(intptr_t len) {
-    ASSERT(0 <= len && len <= kMaxElements);
-    return RoundedAllocationSize(sizeof(UntaggedInstructionsTable) +
-                                 len * kBytesPerElement);
-  }
+  static intptr_t InstanceSize() { return sizeof(UntaggedInstructionsTable); }
 
   static InstructionsTablePtr New(intptr_t length,
                                   uword start_pc,
-                                  uword end_pc);
+                                  uword end_pc,
+                                  uword rodata);
 
-  void SetEntryAt(intptr_t index,
-                  uword payload_start,
-                  bool has_monomorphic_entrypoint,
-                  ObjectPtr descriptor) const;
+  void SetCodeAt(intptr_t index, CodePtr code) const;
 
   bool ContainsPc(uword pc) const { return ContainsPc(ptr(), pc); }
   static bool ContainsPc(InstructionsTablePtr table, uword pc);
 
-  // Looks for the entry in the [table] by the given [pc].
-  // Returns index of an entry which contains [pc], or -1 if not found.
-  static intptr_t FindEntry(InstructionsTablePtr table, uword pc);
+  static CodePtr FindCode(InstructionsTablePtr table, uword pc);
 
-  intptr_t length() const { return InstructionsTable::length(this->ptr()); }
-  static intptr_t length(InstructionsTablePtr table) {
-    return table->untag()->length_;
-  }
+  static const UntaggedCompressedStackMaps::Payload*
+  FindStackMap(InstructionsTablePtr table, uword pc, uword* start_pc);
 
-  // Returns descriptor object for the entry with given index.
-  ObjectPtr DescriptorAt(intptr_t index) const {
-    return InstructionsTable::DescriptorAt(this->ptr(), index);
+  static const UntaggedCompressedStackMaps::Payload* GetCanonicalStackMap(
+      InstructionsTablePtr table);
+
+  const UntaggedInstructionsTable::Data* rodata() const {
+    return ptr()->untag()->rodata_;
   }
-  static ObjectPtr DescriptorAt(InstructionsTablePtr table, intptr_t index);
 
   // Returns start address of the instructions entry with given index.
   uword PayloadStartAt(intptr_t index) const {
@@ -5664,34 +5634,26 @@
     return table->untag()->end_pc_;
   }
 
-  ArrayPtr descriptors() const { return untag()->descriptors_; }
-
-  static uint32_t DataAt(InstructionsTablePtr table, intptr_t index) {
-    ASSERT((0 <= index) && (index < InstructionsTable::length(table)));
-    return table->untag()->data()[index];
-  }
-  uint32_t PcOffsetAt(intptr_t index) const {
-    return InstructionsTable::PcOffsetAt(this->ptr(), index);
-  }
-  static uint32_t PcOffsetAt(InstructionsTablePtr table, intptr_t index) {
-    return DataAt(table, index) & kPayloadMask;
-  }
-  bool HasMonomorphicEntryPointAt(intptr_t index) const {
-    return (DataAt(this->ptr(), index) & kHasMonomorphicEntrypointFlag) != 0;
-  }
+  ArrayPtr code_objects() const { return untag()->code_objects_; }
 
   void set_length(intptr_t value) const;
   void set_start_pc(uword value) const;
   void set_end_pc(uword value) const;
-  void set_descriptors(const Array& value) const;
+  void set_code_objects(const Array& value) const;
+  void set_rodata(uword rodata) const;
 
   uint32_t ConvertPcToOffset(uword pc) const {
     return InstructionsTable::ConvertPcToOffset(this->ptr(), pc);
   }
   static uint32_t ConvertPcToOffset(InstructionsTablePtr table, uword pc);
 
+  static intptr_t FindEntry(InstructionsTablePtr table,
+                            uword pc,
+                            intptr_t start_index = 0);
+
   FINAL_HEAP_OBJECT_IMPLEMENTATION(InstructionsTable, Object);
   friend class Class;
+  friend class Deserializer;
 };
 
 class LocalVarDescriptors : public Object {
@@ -5921,13 +5883,16 @@
   uintptr_t payload_size() const { return PayloadSizeOf(ptr()); }
   static uintptr_t PayloadSizeOf(const CompressedStackMapsPtr raw) {
     return UntaggedCompressedStackMaps::SizeField::decode(
-        raw->untag()->flags_and_size_);
+        raw->untag()->payload()->flags_and_size);
   }
 
+  const uint8_t* data() const { return ptr()->untag()->payload()->data(); }
+
   // Methods to allow use with PointerKeyValueTrait to create sets of CSMs.
   bool Equals(const CompressedStackMaps& other) const {
     // All of the table flags and payload size must match.
-    if (untag()->flags_and_size_ != other.untag()->flags_and_size_) {
+    if (untag()->payload()->flags_and_size !=
+        other.untag()->payload()->flags_and_size) {
       return false;
     }
     NoSafepointScope no_safepoint;
@@ -5935,7 +5900,10 @@
   }
   uword Hash() const;
 
-  static intptr_t HeaderSize() { return sizeof(UntaggedCompressedStackMaps); }
+  static intptr_t HeaderSize() {
+    return sizeof(UntaggedCompressedStackMaps) +
+           sizeof(UntaggedCompressedStackMaps::Payload);
+  }
   static intptr_t UnroundedSize(CompressedStackMapsPtr maps) {
     return UnroundedSize(CompressedStackMaps::PayloadSizeOf(maps));
   }
@@ -5943,8 +5911,6 @@
     return HeaderSize() + length;
   }
   static intptr_t InstanceSize() {
-    ASSERT_EQUAL(sizeof(UntaggedCompressedStackMaps),
-                 OFFSET_OF_RETURNED_VALUE(UntaggedCompressedStackMaps, data));
     return 0;
   }
   static intptr_t InstanceSize(intptr_t length) {
@@ -5954,13 +5920,13 @@
   bool UsesGlobalTable() const { return UsesGlobalTable(ptr()); }
   static bool UsesGlobalTable(const CompressedStackMapsPtr raw) {
     return UntaggedCompressedStackMaps::UsesTableBit::decode(
-        raw->untag()->flags_and_size_);
+        raw->untag()->payload()->flags_and_size);
   }
 
   bool IsGlobalTable() const { return IsGlobalTable(ptr()); }
   static bool IsGlobalTable(const CompressedStackMapsPtr raw) {
     return UntaggedCompressedStackMaps::GlobalTableBit::decode(
-        raw->untag()->flags_and_size_);
+        raw->untag()->payload()->flags_and_size);
   }
 
   static CompressedStackMapsPtr NewInlined(const void* payload, intptr_t size) {
@@ -5979,17 +5945,128 @@
                /*uses_global_table=*/false);
   }
 
+  class RawPayloadHandle {
+   public:
+    RawPayloadHandle() {}
+    RawPayloadHandle(const RawPayloadHandle&) = default;
+    RawPayloadHandle& operator=(const RawPayloadHandle&) = default;
+
+    const UntaggedCompressedStackMaps::Payload* payload() const {
+      return payload_;
+    }
+    bool IsNull() const { return payload_ == nullptr; }
+
+    RawPayloadHandle& operator=(
+        const UntaggedCompressedStackMaps::Payload* payload) {
+      payload_ = payload;
+      return *this;
+    }
+
+    RawPayloadHandle& operator=(const CompressedStackMaps& maps) {
+      ASSERT(!maps.IsNull());
+      payload_ = maps.untag()->payload();
+      return *this;
+    }
+
+    RawPayloadHandle& operator=(CompressedStackMapsPtr maps) {
+      ASSERT(maps != CompressedStackMaps::null());
+      payload_ = maps.untag()->payload();
+      return *this;
+    }
+
+    uintptr_t payload_size() const {
+      return UntaggedCompressedStackMaps::SizeField::decode(
+          payload()->flags_and_size);
+    }
+    const uint8_t* data() const { return payload()->data(); }
+
+    bool UsesGlobalTable() const {
+      return UntaggedCompressedStackMaps::UsesTableBit::decode(
+          payload()->flags_and_size);
+    }
+
+    bool IsGlobalTable() const {
+      return UntaggedCompressedStackMaps::GlobalTableBit::decode(
+          payload()->flags_and_size);
+    }
+
+   private:
+    const UntaggedCompressedStackMaps::Payload* payload_ = nullptr;
+  };
+
+  template <typename PayloadHandle>
   class Iterator {
    public:
-    Iterator(const CompressedStackMaps& maps,
-             const CompressedStackMaps& global_table);
-    Iterator(Thread* thread, const CompressedStackMaps& maps);
+    Iterator(const PayloadHandle& maps, const PayloadHandle& global_table)
+        : maps_(maps),
+          bits_container_(maps.UsesGlobalTable() ? global_table : maps) {
+      ASSERT(!maps_.IsNull());
+      ASSERT(!bits_container_.IsNull());
+      ASSERT(!maps_.IsGlobalTable());
+      ASSERT(!maps_.UsesGlobalTable() || bits_container_.IsGlobalTable());
+    }
 
-    explicit Iterator(const CompressedStackMaps::Iterator& it);
+    Iterator(const Iterator& it)
+        : maps_(it.maps_),
+          bits_container_(it.bits_container_),
+          next_offset_(it.next_offset_),
+          current_pc_offset_(it.current_pc_offset_),
+          current_global_table_offset_(it.current_global_table_offset_),
+          current_spill_slot_bit_count_(it.current_spill_slot_bit_count_),
+          current_non_spill_slot_bit_count_(it.current_spill_slot_bit_count_),
+          current_bits_offset_(it.current_bits_offset_) {}
 
     // Loads the next entry from [maps_], if any. If [maps_] is the null value,
     // this always returns false.
-    bool MoveNext();
+    bool MoveNext() {
+      if (next_offset_ >= maps_.payload_size()) {
+        return false;
+      }
+
+      NoSafepointScope scope;
+      ReadStream stream(maps_.data(), maps_.payload_size(), next_offset_);
+
+      auto const pc_delta = stream.ReadLEB128();
+      ASSERT(pc_delta <= (kMaxUint32 - current_pc_offset_));
+      current_pc_offset_ += pc_delta;
+
+      // Table-using CSMs have a table offset after the PC offset delta, whereas
+      // the post-delta part of inlined entries has the same information as
+      // global table entries.
+      // See comments in UntaggedCompressedStackMaps for description of
+      // encoding.
+      if (maps_.UsesGlobalTable()) {
+        current_global_table_offset_ = stream.ReadLEB128();
+        ASSERT(current_global_table_offset_ < bits_container_.payload_size());
+
+        // Since generally we only use entries in the GC and the GC only needs
+        // the rest of the entry information if the PC offset matches, we lazily
+        // load and cache the information stored in the global object when it is
+        // actually requested.
+        current_spill_slot_bit_count_ = -1;
+        current_non_spill_slot_bit_count_ = -1;
+        current_bits_offset_ = -1;
+
+        next_offset_ = stream.Position();
+      } else {
+        current_spill_slot_bit_count_ = stream.ReadLEB128();
+        ASSERT(current_spill_slot_bit_count_ >= 0);
+
+        current_non_spill_slot_bit_count_ = stream.ReadLEB128();
+        ASSERT(current_non_spill_slot_bit_count_ >= 0);
+
+        const auto stackmap_bits =
+            current_spill_slot_bit_count_ + current_non_spill_slot_bit_count_;
+        const uintptr_t stackmap_size =
+            Utils::RoundUp(stackmap_bits, kBitsPerByte) >> kBitsPerByteLog2;
+        ASSERT(stackmap_size <= (maps_.payload_size() - stream.Position()));
+
+        current_bits_offset_ = stream.Position();
+        next_offset_ = current_bits_offset_ + stackmap_size;
+      }
+
+      return true;
+    }
 
     // Finds the entry with the given PC offset starting at the current position
     // of the iterator. If [maps_] is the null value, this always returns false.
@@ -6013,21 +6090,56 @@
     }
 
     // Returns the bit length of the loaded entry.
-    intptr_t Length() const;
+    intptr_t Length() const {
+      EnsureFullyLoadedEntry();
+      return current_spill_slot_bit_count_ + current_non_spill_slot_bit_count_;
+    }
     // Returns the number of spill slot bits of the loaded entry.
-    intptr_t SpillSlotBitCount() const;
+    intptr_t SpillSlotBitCount() const {
+      EnsureFullyLoadedEntry();
+      return current_spill_slot_bit_count_;
+    }
     // Returns whether the stack entry represented by the offset contains
-    // a tagged objecet.
-    bool IsObject(intptr_t bit_offset) const;
-
-    void WriteToBuffer(BaseTextBuffer* buffer, const char* separator) const;
+    // a tagged object.
+    bool IsObject(intptr_t bit_index) const {
+      EnsureFullyLoadedEntry();
+      ASSERT(bit_index >= 0 && bit_index < Length());
+      const intptr_t byte_index = bit_index >> kBitsPerByteLog2;
+      const intptr_t bit_remainder = bit_index & (kBitsPerByte - 1);
+      uint8_t byte_mask = 1U << bit_remainder;
+      const intptr_t byte_offset = current_bits_offset_ + byte_index;
+      NoSafepointScope scope;
+      return (bits_container_.data()[byte_offset] & byte_mask) != 0;
+    }
 
    private:
     bool HasLoadedEntry() const { return next_offset_ > 0; }
 
     // Caches the corresponding values from the global table in the mutable
     // fields. We lazily load these as some clients only need the PC offset.
-    void LazyLoadGlobalTableEntry() const;
+    void LazyLoadGlobalTableEntry() const {
+      ASSERT(maps_.UsesGlobalTable());
+      ASSERT(HasLoadedEntry());
+      ASSERT(current_global_table_offset_ < bits_container_.payload_size());
+
+      NoSafepointScope scope;
+      ReadStream stream(bits_container_.data(), bits_container_.payload_size(),
+                        current_global_table_offset_);
+
+      current_spill_slot_bit_count_ = stream.ReadLEB128();
+      ASSERT(current_spill_slot_bit_count_ >= 0);
+
+      current_non_spill_slot_bit_count_ = stream.ReadLEB128();
+      ASSERT(current_non_spill_slot_bit_count_ >= 0);
+
+      const auto stackmap_bits = Length();
+      const uintptr_t stackmap_size =
+          Utils::RoundUp(stackmap_bits, kBitsPerByte) >> kBitsPerByteLog2;
+      ASSERT(stackmap_size <=
+             (bits_container_.payload_size() - stream.Position()));
+
+      current_bits_offset_ = stream.Position();
+    }
 
     void EnsureFullyLoadedEntry() const {
       ASSERT(HasLoadedEntry());
@@ -6037,8 +6149,8 @@
       }
     }
 
-    const CompressedStackMaps& maps_;
-    const CompressedStackMaps& bits_container_;
+    const PayloadHandle& maps_;
+    const PayloadHandle& bits_container_;
 
     uintptr_t next_offset_ = 0;
     uint32_t current_pc_offset_ = 0;
@@ -6054,6 +6166,10 @@
     friend class StackMapEntry;
   };
 
+  Iterator<CompressedStackMaps> iterator(Thread* thread) const;
+
+  void WriteToBuffer(BaseTextBuffer* buffer, const char* separator) const;
+
  private:
   static CompressedStackMapsPtr New(const void* payload,
                                     intptr_t size,
@@ -6287,6 +6403,10 @@
 #endif
   }
 
+  static uword UncheckedEntryPointOf(const CodePtr code) {
+    return code->untag()->unchecked_entry_point_;
+  }
+
   // Returns the unchecked entry point of [instructions()].
   uword UncheckedEntryPoint() const {
 #if defined(DART_PRECOMPILED_RUNTIME)
@@ -7516,7 +7636,7 @@
   virtual ObjectPtr HashCode() const;
 
   // Equivalent to invoking identityHashCode with this instance.
-  ObjectPtr IdentityHashCode() const;
+  IntegerPtr IdentityHashCode(Thread* thread) const;
 
   static intptr_t InstanceSize() {
     return RoundedAllocationSize(sizeof(UntaggedInstance));
@@ -9763,6 +9883,7 @@
   friend class Symbols;
   friend class Utf8;
   friend class OneByteStringMessageSerializationCluster;
+  friend class Deserializer;
 };
 
 class TwoByteString : public AllStatic {
@@ -10064,6 +10185,11 @@
   friend class Symbols;
 };
 
+// Matches null_patch.dart / bool_patch.dart.
+static constexpr intptr_t kNullIdentityHash = 2011;
+static constexpr intptr_t kTrueIdentityHash = 1231;
+static constexpr intptr_t kFalseIdentityHash = 1237;
+
 // Class Bool implements Dart core class bool.
 class Bool : public Instance {
  public:
@@ -10082,7 +10208,7 @@
   }
 
   virtual uint32_t CanonicalizeHash() const {
-    return ptr() == True().ptr() ? 1231 : 1237;
+    return ptr() == True().ptr() ? kTrueIdentityHash : kFalseIdentityHash;
   }
 
  private:
@@ -11904,6 +12030,12 @@
     ASSERT(t < UserTags::kUserTagIdOffset + UserTags::kMaxUserTags);
     StoreNonPointer(&untag()->tag_, t);
   }
+
+  bool streamable() const { return untag()->streamable(); }
+  void set_streamable(bool streamable) {
+    StoreNonPointer(&untag()->streamable_, streamable);
+  }
+
   static intptr_t tag_offset() { return OFFSET_OF(UntaggedUserTag, tag_); }
 
   StringPtr label() const { return untag()->label(); }
@@ -11919,6 +12051,9 @@
 
   static bool TagTableIsFull(Thread* thread);
   static UserTagPtr FindTagById(uword tag_id);
+  static UserTagPtr FindTagInIsolate(Isolate* isolate,
+                                     Thread* thread,
+                                     const String& label);
 
  private:
   static UserTagPtr FindTagInIsolate(Thread* thread, const String& label);
diff --git a/runtime/vm/object_test.cc b/runtime/vm/object_test.cc
index c8cbcec..b2dce5c 100644
--- a/runtime/vm/object_test.cc
+++ b/runtime/vm/object_test.cc
@@ -4545,13 +4545,14 @@
     ElideJSONSubstring("libraries", buffer, buffer);
     ElideJSONSubstring("_List@", buffer, buffer);
     ElideJSONSubstring("_TypeParameter@", buffer, buffer);
+    StripTokenPositions(buffer);
     EXPECT_SUBSTRING(
         "{\"type\":\"@Instance\",\"_vmType\":\"Array\",\"class\":{\"type\":\"@"
         "Class\",\"fixedId\":true,\"id\":\"\",\"name\":\"_List\",\"_vmName\":"
         "\"\",\"location\":{\"type\":\"SourceLocation\",\"script\":{\"type\":"
         "\"@Script\",\"fixedId\":true,\"id\":\"\",\"uri\":\"dart:core-patch\\/"
-        "array.dart\",\"_kind\":\"kernel\"},\"tokenPos\":248,\"endTokenPos\":"
-        "7917},\"library\":{\"type\":\"@Library\",\"fixedId\":true,\"id\":\"\","
+        "array.dart\",\"_kind\":\"kernel\"}},"
+        "\"library\":{\"type\":\"@Library\",\"fixedId\":true,\"id\":\"\","
         "\"name\":\"dart.core\",\"uri\":\"dart:core\"},\"typeParameters\":[{"
         "\"type\":\"@"
         "Instance\",\"_vmType\":\"TypeParameter\",\"class\":{\"type\":\"@"
@@ -4559,8 +4560,8 @@
         "vmName\":\"\",\"location\":{\"type\":"
         "\"SourceLocation\",\"script\":{\"type\":\"@Script\",\"fixedId\":true,"
         "\"id\":\"\",\"uri\":\"dart:core-patch\\/"
-        "type_patch.dart\",\"_kind\":\"kernel\"},\"tokenPos\":1749,"
-        "\"endTokenPos\":1894},\"library\":{\"type\":\"@Library\",\"fixedId\":"
+        "type_patch.dart\",\"_kind\":\"kernel\"}},"
+        "\"library\":{\"type\":\"@Library\",\"fixedId\":"
         "true,\"id\":\"\",\"name\":\"dart.core\",\"uri\":\"dart:core\"}},"
         "\"identityHashCode\":",
         buffer);
@@ -4572,8 +4573,8 @@
         "\"Null\",\"location\":{\"type\":\"SourceLocation\",\"script\":{"
         "\"type\":\"@Script\",\"fixedId\":true,\"id\":\"\",\"uri\":\"dart:"
         "core\\/"
-        "null.dart\",\"_kind\":\"kernel\"},\"tokenPos\":925,\"endTokenPos\":"
-        "1165},\"library\":{\"type\":\"@Library\",\"fixedId\":true,\"id\":\"\","
+        "null.dart\",\"_kind\":\"kernel\"}},"
+        "\"library\":{\"type\":\"@Library\",\"fixedId\":true,\"id\":\"\","
         "\"name\":\"dart.core\",\"uri\":\"dart:core\"}},\"kind\":\"Null\","
         "\"fixedId\":true,\"id\":\"\",\"valueAsString\":\"null\"}}]},"
         "\"identityHashCode\":0,\"kind\":\"List\",\"id\":\"\",\"length\":0}",
diff --git a/runtime/vm/profiler_service.cc b/runtime/vm/profiler_service.cc
index 1ae3a46..52903dc 100644
--- a/runtime/vm/profiler_service.cc
+++ b/runtime/vm/profiler_service.cc
@@ -955,12 +955,12 @@
     if (!FilterSamples()) {
       return;
     }
-
     Setup();
     BuildCodeTable();
     FinalizeCodeIndexes();
     BuildFunctionTable();
     PopulateFunctionTicks();
+    SanitizeMinMaxTimes();
   }
 
  private:
@@ -1062,7 +1062,6 @@
       TickExitFrame(sample->vm_tag(), sample_index, sample);
       thread_->CheckForSafepoint();
     }
-    SanitizeMinMaxTimes();
   }
 
   void FinalizeCodeIndexes() {
diff --git a/runtime/vm/program_visitor.cc b/runtime/vm/program_visitor.cc
index 918f7d7..9d57230 100644
--- a/runtime/vm/program_visitor.cc
+++ b/runtime/vm/program_visitor.cc
@@ -454,7 +454,8 @@
 
 class StackMapEntry : public ZoneAllocated {
  public:
-  StackMapEntry(Zone* zone, const CompressedStackMaps::Iterator& it)
+  StackMapEntry(Zone* zone,
+                const CompressedStackMaps::Iterator<CompressedStackMaps>& it)
       : maps_(CompressedStackMaps::Handle(zone, it.maps_.ptr())),
         bits_container_(
             CompressedStackMaps::Handle(zone, it.bits_container_.ptr())),
@@ -525,7 +526,7 @@
   }
   const uint8_t* PayloadData() const {
     ASSERT(!Thread::Current()->IsAtSafepoint());
-    return bits_container_.ptr()->untag()->data() + bits_offset_;
+    return bits_container_.ptr()->untag()->payload()->data() + bits_offset_;
   }
 
   const CompressedStackMaps& maps_;
@@ -582,8 +583,8 @@
 
     void VisitCode(const Code& code) {
       compressed_stackmaps_ = code.compressed_stackmaps();
-      CompressedStackMaps::Iterator it(compressed_stackmaps_,
-                                       old_global_table_);
+      CompressedStackMaps::Iterator<CompressedStackMaps> it(
+          compressed_stackmaps_, old_global_table_);
       while (it.MoveNext()) {
         auto const entry = new (zone_) StackMapEntry(zone_, it);
         auto const index = entry_indices_.LookupValue(entry);
@@ -705,7 +706,8 @@
         return Object::empty_compressed_stackmaps().ptr();
       }
       MallocWriteStream new_payload(maps.payload_size());
-      CompressedStackMaps::Iterator it(maps, old_global_table_);
+      CompressedStackMaps::Iterator<CompressedStackMaps> it(maps,
+                                                            old_global_table_);
       intptr_t last_offset = 0;
       while (it.MoveNext()) {
         StackMapEntry entry(zone_, it);
@@ -1269,6 +1271,82 @@
           code_(Code::Handle(zone)),
           instructions_(Instructions::Handle(zone)) {}
 
+    // Relink the program graph to eliminate references to the non-canonical
+    // Code objects. We want to arrive to the graph where Code objects
+    // and Instruction objects are in one-to-one relationship.
+    void PostProcess(IsolateGroup* isolate_group) {
+      const intptr_t canonical_count = canonical_objects_.Length();
+
+      auto& static_calls_array = Array::Handle(zone_);
+      auto& static_calls_table_entry = Object::Handle(zone_);
+
+      auto should_canonicalize = [&](const Object& obj) {
+        return CanCanonicalize(Code::Cast(obj)) && !obj.InVMIsolateHeap();
+      };
+
+      auto process_pool = [&](const ObjectPool& pool) {
+        if (pool.IsNull()) {
+          return;
+        }
+
+        auto& object = Object::Handle(zone_);
+        for (intptr_t i = 0; i < pool.Length(); i++) {
+          auto const type = pool.TypeAt(i);
+          if (type != ObjectPool::EntryType::kTaggedObject) continue;
+          object = pool.ObjectAt(i);
+          if (object.IsCode() && should_canonicalize(object)) {
+            object = Canonicalize(Code::Cast(object));
+            pool.SetObjectAt(i, object);
+          }
+        }
+      };
+
+      auto& pool = ObjectPool::Handle(zone_);
+
+      auto it = canonical_objects_.GetIterator();
+      while (auto canonical_code = it.Next()) {
+        static_calls_array = (*canonical_code)->static_calls_target_table();
+        if (!static_calls_array.IsNull()) {
+          StaticCallsTable static_calls(static_calls_array);
+          for (auto& view : static_calls) {
+            static_calls_table_entry =
+                view.Get<Code::kSCallTableCodeOrTypeTarget>();
+            if (static_calls_table_entry.IsCode() &&
+                should_canonicalize(static_calls_table_entry)) {
+              static_calls_table_entry =
+                  Canonicalize(Code::Cast(static_calls_table_entry));
+              view.Set<Code::kSCallTableCodeOrTypeTarget>(
+                  static_calls_table_entry);
+            }
+          }
+        }
+
+        pool = (*canonical_code)->object_pool();
+        process_pool(pool);
+      }
+
+      auto object_store = isolate_group->object_store();
+
+      const auto& dispatch_table_entries =
+          Array::Handle(zone_, object_store->dispatch_table_code_entries());
+      if (!dispatch_table_entries.IsNull()) {
+        auto& code = Code::Handle(zone_);
+        for (intptr_t i = 0; i < dispatch_table_entries.Length(); i++) {
+          code ^= dispatch_table_entries.At(i);
+          if (should_canonicalize(code)) {
+            code ^= Canonicalize(code);
+            dispatch_table_entries.SetAt(i, code);
+          }
+        }
+      }
+
+      // If there's a global object pool, add any visitable objects.
+      pool = object_store->global_object_pool();
+      process_pool(pool);
+
+      RELEASE_ASSERT(canonical_count == canonical_objects_.Length());
+    }
+
     void VisitFunction(const Function& function) {
       if (!function.HasCode()) return;
       code_ = function.CurrentCode();
@@ -1276,12 +1354,13 @@
       // ProgramWalker, but as long as the deduplication process is idempotent,
       // the cached entry points won't change during the second visit.
       VisitCode(code_);
-      function.SetInstructionsSafe(code_);  // Update cached entry point.
+      function.SetInstructionsSafe(canonical_);  // Update cached entry point.
     }
 
     void VisitCode(const Code& code) {
+      canonical_ = code.ptr();
       if (code.IsDisabled()) return;
-      canonical_ = Dedup(code);
+      canonical_ = Canonicalize(code);
       instructions_ = canonical_.instructions();
       code.SetActiveInstructionsSafe(instructions_,
                                      code.UncheckedEntryPointOffset());
@@ -1291,6 +1370,14 @@
    private:
     bool CanCanonicalize(const Code& code) const { return !code.IsDisabled(); }
 
+    CodePtr Canonicalize(const Code& code) {
+      canonical_ = Dedup(code);
+      if (!code.is_discarded() && canonical_.is_discarded()) {
+        canonical_.set_is_discarded(false);
+      }
+      return canonical_.ptr();
+    }
+
     Code& canonical_;
     Code& code_;
     Instructions& instructions_;
@@ -1300,6 +1387,7 @@
     StackZone stack_zone(thread);
     DedupInstructionsWithSameMetadataVisitor visitor(thread->zone());
     WalkProgram(thread->zone(), thread->isolate_group(), &visitor);
+    visitor.PostProcess(thread->isolate_group());
     return;
   }
 #endif  // defined(DART_PRECOMPILER)
diff --git a/runtime/vm/raw_object.cc b/runtime/vm/raw_object.cc
index de93e86..c32aa1e 100644
--- a/runtime/vm/raw_object.cc
+++ b/runtime/vm/raw_object.cc
@@ -115,13 +115,6 @@
       instance_size = InstructionsSection::InstanceSize(section_size);
       break;
     }
-    case kInstructionsTableCid: {
-      const InstructionsTablePtr raw_instructions_table =
-          static_cast<const InstructionsTablePtr>(this);
-      intptr_t length = raw_instructions_table->untag()->length_;
-      instance_size = InstructionsTable::InstanceSize(length);
-      break;
-    }
     case kContextCid: {
       const ContextPtr raw_context = static_cast<const ContextPtr>(this);
       intptr_t num_variables = raw_context->untag()->num_variables_;
@@ -575,7 +568,7 @@
         Smi::Value(raw_obj->untag()->length()))
 VARIABLE_COMPRESSED_VISITOR(ContextScope, raw_obj->untag()->num_variables_)
 NULL_VISITOR(Sentinel)
-VARIABLE_VISITOR(InstructionsTable, raw_obj->untag()->length_)
+REGULAR_VISITOR(InstructionsTable)
 NULL_VISITOR(Mint)
 NULL_VISITOR(Double)
 NULL_VISITOR(Float32x4)
diff --git a/runtime/vm/raw_object.h b/runtime/vm/raw_object.h
index 6a182bb..b0b62cd 100644
--- a/runtime/vm/raw_object.h
+++ b/runtime/vm/raw_object.h
@@ -1864,22 +1864,6 @@
   friend class Image;
 };
 
-class UntaggedInstructionsTable : public UntaggedObject {
-  RAW_HEAP_OBJECT_IMPLEMENTATION(InstructionsTable);
-
-  POINTER_FIELD(ArrayPtr, descriptors)
-  VISIT_FROM(descriptors)
-  VISIT_TO(descriptors)
-
-  intptr_t length_;
-  uword start_pc_;
-  uword end_pc_;
-
-  // Variable length data follows here.
-  uint32_t* data() { OPEN_ARRAY_START(uint32_t, uint32_t); }
-  const uint32_t* data() const { OPEN_ARRAY_START(uint32_t, uint32_t); }
-};
-
 class UntaggedPcDescriptors : public UntaggedObject {
  public:
 // The macro argument V is passed two arguments, the raw name of the enum value
@@ -2002,75 +1986,130 @@
   RAW_HEAP_OBJECT_IMPLEMENTATION(CompressedStackMaps);
   VISIT_NOTHING();
 
-  // The most significant bits are the length of the encoded payload, in bytes.
-  // The low bits determine the expected payload contents, as described below.
-  uint32_t flags_and_size_;
+ public:
+  struct Payload {
+    // The most significant bits are the length of the encoded payload, in
+    // bytes (excluding the header itself). The low bits determine the
+    // expected payload contents, as described below.
+    uint32_t flags_and_size;
 
-  // Variable length data follows here. The contents of the payload depend on
-  // the type of CompressedStackMaps (CSM) being represented. There are three
-  // major types of CSM:
-  //
-  // 1) GlobalTableBit = false, UsesTableBit = false: CSMs that include all
-  //    information about the stack maps. The payload for these contain tightly
-  //    packed entries with the following information:
-  //
-  //   * A header containing the following three pieces of information:
-  //     * An unsigned integer representing the PC offset as a delta from the
-  //       PC offset of the previous entry (from 0 for the first entry).
-  //     * An unsigned integer representing the number of bits used for
-  //       spill slot entries.
-  //     * An unsigned integer representing the number of bits used for other
-  //       entries.
-  //   * The body containing the bits for the stack map. The length of the body
-  //     in bits is the sum of the spill slot and non-spill slot bit counts.
-  //
-  // 2) GlobalTableBit = false, UsesTableBit = true: CSMs where the majority of
-  //    the stack map information has been offloaded and canonicalized into a
-  //    global table. The payload contains tightly packed entries with the
-  //    following information:
-  //
-  //   * A header containing just an unsigned integer representing the PC offset
-  //     delta as described above.
-  //   * The body is just an unsigned integer containing the offset into the
-  //     payload for the global table.
-  //
-  // 3) GlobalTableBit = true, UsesTableBit = false: A CSM implementing the
-  //    global table. Here, the payload contains tightly packed entries with
-  //    the following information:
-  //
-  //   * A header containing the following two pieces of information:
-  //     * An unsigned integer representing the number of bits used for
-  //       spill slot entries.
-  //     * An unsigned integer representing the number of bits used for other
-  //       entries.
-  //   * The body containing the bits for the stack map. The length of the body
-  //     in bits is the sum of the spill slot and non-spill slot bit counts.
-  //
-  // In all types of CSM, each unsigned integer is LEB128 encoded, as generally
-  // they tend to fit in a single byte or two. Thus, entry headers are not a
-  // fixed length, and currently there is no random access of entries.  In
-  // addition, PC offsets are currently encoded as deltas, which also inhibits
-  // random access without accessing previous entries. That means to find an
-  // entry for a given PC offset, a linear search must be done where the payload
-  // is decoded up to the entry whose PC offset is >= the given PC.
+    // Variable length data follows here. The contents of the payload depend on
+    // the type of CompressedStackMaps (CSM) being represented. There are three
+    // major types of CSM:
+    //
+    // 1) GlobalTableBit = false, UsesTableBit = false: CSMs that include all
+    //    information about the stack maps. The payload for these contain
+    //    tightly packed entries with the following information:
+    //
+    //   * A header containing the following three pieces of information:
+    //     * An unsigned integer representing the PC offset as a delta from the
+    //       PC offset of the previous entry (from 0 for the first entry).
+    //     * An unsigned integer representing the number of bits used for
+    //       spill slot entries.
+    //     * An unsigned integer representing the number of bits used for other
+    //       entries.
+    //   * The body containing the bits for the stack map. The length of
+    //     the body in bits is the sum of the spill slot and non-spill slot
+    //     bit counts.
+    //
+    // 2) GlobalTableBit = false, UsesTableBit = true: CSMs where the majority
+    //    of the stack map information has been offloaded and canonicalized into
+    //    a global table. The payload contains tightly packed entries with the
+    //    following information:
+    //
+    //   * A header containing just an unsigned integer representing the PC
+    //     offset delta as described above.
+    //   * The body is just an unsigned integer containing the offset into the
+    //     payload for the global table.
+    //
+    // 3) GlobalTableBit = true, UsesTableBit = false: A CSM implementing the
+    //    global table. Here, the payload contains tightly packed entries with
+    //    the following information:
+    //
+    //   * A header containing the following two pieces of information:
+    //     * An unsigned integer representing the number of bits used for
+    //       spill slot entries.
+    //     * An unsigned integer representing the number of bits used for other
+    //       entries.
+    //   * The body containing the bits for the stack map. The length of the
+    //     body in bits is the sum of the spill slot and non-spill slot bit
+    //     counts.
+    //
+    // In all types of CSM, each unsigned integer is LEB128 encoded, as
+    // generally they tend to fit in a single byte or two. Thus, entry headers
+    // are not a fixed length, and currently there is no random access of
+    // entries.  In addition, PC offsets are currently encoded as deltas, which
+    // also inhibits random access without accessing previous entries. That
+    // means to find an entry for a given PC offset, a linear search must be
+    // done where the payload is decoded up to the entry whose PC offset
+    // is greater or equal to the given PC.
 
-  uint8_t* data() { OPEN_ARRAY_START(uint8_t, uint8_t); }
-  const uint8_t* data() const { OPEN_ARRAY_START(uint8_t, uint8_t); }
+    uint8_t* data() { OPEN_ARRAY_START(uint8_t, uint8_t); }
+    const uint8_t* data() const { OPEN_ARRAY_START(uint8_t, uint8_t); }
+  };
+  static_assert(sizeof(Payload) == sizeof(uint32_t));
+
+ private:
+  // We are using OPEN_ARRAY_START rather than embedding Payload directly into
+  // the UntaggedCompressedStackMaps as a field because that would introduce a
+  // padding at the end of UntaggedCompressedStackMaps - so we would not be
+  // able to use sizeof(UntaggedCompressedStackMaps) as the size of the header
+  // anyway.
+  Payload* payload() { OPEN_ARRAY_START(Payload, uint32_t); }
+  const Payload* payload() const { OPEN_ARRAY_START(Payload, uint32_t); }
 
   class GlobalTableBit : public BitField<uint32_t, bool, 0, 1> {};
   class UsesTableBit
       : public BitField<uint32_t, bool, GlobalTableBit::kNextBit, 1> {};
-  class SizeField : public BitField<uint32_t,
-                                    uint32_t,
-                                    UsesTableBit::kNextBit,
-                                    sizeof(flags_and_size_) * kBitsPerByte -
-                                        UsesTableBit::kNextBit> {};
+  class SizeField
+      : public BitField<uint32_t,
+                        uint32_t,
+                        UsesTableBit::kNextBit,
+                        sizeof(Payload::flags_and_size) * kBitsPerByte -
+                            UsesTableBit::kNextBit> {};
 
   friend class Object;
   friend class ImageWriter;
   friend class StackMapEntry;
 };
 
+class UntaggedInstructionsTable : public UntaggedObject {
+  RAW_HEAP_OBJECT_IMPLEMENTATION(InstructionsTable);
+
+  POINTER_FIELD(ArrayPtr, code_objects)
+  VISIT_FROM(code_objects)
+  VISIT_TO(code_objects)
+
+  struct DataEntry {
+    uint32_t pc_offset;
+    uint32_t stack_map_offset;
+  };
+  static_assert(sizeof(DataEntry) == sizeof(uint32_t) * 2);
+
+  struct Data {
+    uint32_t canonical_stack_map_entries_offset;
+    uint32_t length;
+    uint32_t first_entry_with_code;
+    uint32_t padding;
+
+    const DataEntry* entries() const { OPEN_ARRAY_START(DataEntry, uint32_t); }
+
+    const UntaggedCompressedStackMaps::Payload* StackMapAt(
+        intptr_t offset) const {
+      return reinterpret_cast<UntaggedCompressedStackMaps::Payload*>(
+          reinterpret_cast<uword>(this) + offset);
+    }
+  };
+  static_assert(sizeof(Data) == sizeof(uint32_t) * 4);
+
+  intptr_t length_;
+  const Data* rodata_;
+  uword start_pc_;
+  uword end_pc_;
+
+  friend class Deserializer;
+};
+
 class UntaggedLocalVarDescriptors : public UntaggedObject {
  public:
   enum VarInfoKind {
@@ -3244,10 +3283,14 @@
   // Isolate unique tag.
   uword tag_;
 
+  // Should CPU samples with this tag be streamed?
+  bool streamable_;
+
   friend class Object;
 
  public:
   uword tag() const { return tag_; }
+  bool streamable() const { return streamable_; }
 };
 
 class UntaggedFutureOr : public UntaggedInstance {
diff --git a/runtime/vm/raw_object_fields.cc b/runtime/vm/raw_object_fields.cc
index 1099528..e59f439 100644
--- a/runtime/vm/raw_object_fields.cc
+++ b/runtime/vm/raw_object_fields.cc
@@ -104,7 +104,7 @@
   F(ICData, args_descriptor_)                                                  \
   F(ICData, entries_)                                                          \
   F(ICData, owner_)                                                            \
-  F(InstructionsTable, descriptors_)                                           \
+  F(InstructionsTable, code_objects_)                                          \
   F(MegamorphicCache, target_name_)                                            \
   F(MegamorphicCache, args_descriptor_)                                        \
   F(MegamorphicCache, buckets_)                                                \
diff --git a/runtime/vm/reverse_pc_lookup_cache.cc b/runtime/vm/reverse_pc_lookup_cache.cc
index 97bf223..77d4716 100644
--- a/runtime/vm/reverse_pc_lookup_cache.cc
+++ b/runtime/vm/reverse_pc_lookup_cache.cc
@@ -11,10 +11,9 @@
 
 namespace dart {
 
-ObjectPtr ReversePc::FindCodeDescriptorInGroup(IsolateGroup* group,
-                                               uword pc,
-                                               bool is_return_address,
-                                               uword* code_start) {
+CodePtr ReversePc::FindCodeInGroup(IsolateGroup* group,
+                                   uword pc,
+                                   bool is_return_address) {
 #if defined(DART_PRECOMPILED_RUNTIME)
   // This can run in the middle of GC and must not allocate handles.
   NoSafepointScope no_safepoint;
@@ -31,30 +30,80 @@
   for (intptr_t i = 0; i < tables_length; i++) {
     InstructionsTablePtr table = static_cast<InstructionsTablePtr>(
         tables->untag()->data()->untag()->element(i));
-    intptr_t index = InstructionsTable::FindEntry(table, pc);
-    if (index >= 0) {
-      *code_start = InstructionsTable::PayloadStartAt(table, index);
-      return InstructionsTable::DescriptorAt(table, index);
+    CodePtr code = InstructionsTable::FindCode(table, pc);
+    if (code != Code::null()) {
+      return code;
+    }
+  }
+#endif  // defined(DART_PRECOMPILED_RUNTIME)
+  return Code::null();
+}
+
+const UntaggedCompressedStackMaps::Payload* ReversePc::FindStackMapInGroup(
+    IsolateGroup* group,
+    uword pc,
+    bool is_return_address,
+    uword* code_start,
+    const UntaggedCompressedStackMaps::Payload** global_table) {
+#if defined(DART_PRECOMPILED_RUNTIME)
+  // This can run in the middle of GC and must not allocate handles.
+  NoSafepointScope no_safepoint;
+
+  if (is_return_address) {
+    pc--;
+  }
+
+  // This expected number of tables is low (one per loading unit), so we go
+  // through them linearly. If this changes, would could sort the table list
+  // during deserialization and binary search for the table.
+  GrowableObjectArrayPtr tables = group->object_store()->instructions_tables();
+  intptr_t tables_length = Smi::Value(tables->untag()->length());
+  for (intptr_t i = 0; i < tables_length; i++) {
+    InstructionsTablePtr table = static_cast<InstructionsTablePtr>(
+        tables->untag()->data()->untag()->element(i));
+    auto map = InstructionsTable::FindStackMap(table, pc, code_start);
+    if (map != nullptr) {
+      // Take global table from the first table.
+      table = static_cast<InstructionsTablePtr>(
+          tables->untag()->data()->untag()->element(0));
+      *global_table = InstructionsTable::GetCanonicalStackMap(table);
+      return map;
     }
   }
 #endif  // defined(DART_PRECOMPILED_RUNTIME)
 
   *code_start = 0;
-  return Object::null();
+  return nullptr;
 }
 
-ObjectPtr ReversePc::FindCodeDescriptor(IsolateGroup* group,
-                                        uword pc,
-                                        bool is_return_address,
-                                        uword* code_start) {
+const UntaggedCompressedStackMaps::Payload* ReversePc::FindStackMap(
+    IsolateGroup* group,
+    uword pc,
+    bool is_return_address,
+    uword* code_start,
+    const UntaggedCompressedStackMaps::Payload** global_table) {
   ASSERT(FLAG_precompiled_mode);
   NoSafepointScope no_safepoint;
 
-  ObjectPtr code_descriptor =
-      FindCodeDescriptorInGroup(group, pc, is_return_address, code_start);
-  if (code_descriptor == Object::null()) {
-    code_descriptor = FindCodeDescriptorInGroup(Dart::vm_isolate_group(), pc,
-                                                is_return_address, code_start);
+  auto map = FindStackMapInGroup(group, pc, is_return_address, code_start,
+                                 global_table);
+  if (map == nullptr) {
+    map = FindStackMapInGroup(Dart::vm_isolate_group(), pc, is_return_address,
+                              code_start, global_table);
+  }
+  return map;
+}
+
+CodePtr ReversePc::FindCode(IsolateGroup* group,
+                            uword pc,
+                            bool is_return_address) {
+  ASSERT(FLAG_precompiled_mode);
+  NoSafepointScope no_safepoint;
+
+  auto code_descriptor = FindCodeInGroup(group, pc, is_return_address);
+  if (code_descriptor == Code::null()) {
+    code_descriptor =
+        FindCodeInGroup(Dart::vm_isolate_group(), pc, is_return_address);
   }
   return code_descriptor;
 }
@@ -65,44 +114,7 @@
   ASSERT(FLAG_precompiled_mode);
   NoSafepointScope no_safepoint;
 
-  uword code_start;
-  ObjectPtr code_descriptor =
-      FindCodeDescriptor(group, pc, is_return_address, &code_start);
-  if (code_descriptor != Object::null()) {
-    if (!code_descriptor->IsCode()) {
-      ASSERT(StubCode::UnknownDartCode().PayloadStart() == 0);
-      ASSERT(StubCode::UnknownDartCode().Size() == kUwordMax);
-      ASSERT(StubCode::UnknownDartCode().IsFunctionCode());
-      ASSERT(StubCode::UnknownDartCode().IsUnknownDartCode());
-      code_descriptor = StubCode::UnknownDartCode().ptr();
-    }
-  }
-  return static_cast<CodePtr>(code_descriptor);
-}
-
-CompressedStackMapsPtr ReversePc::FindCompressedStackMaps(
-    IsolateGroup* group,
-    uword pc,
-    bool is_return_address,
-    uword* code_start) {
-  ASSERT(FLAG_precompiled_mode);
-  NoSafepointScope no_safepoint;
-
-  ObjectPtr code_descriptor =
-      FindCodeDescriptor(group, pc, is_return_address, code_start);
-  if (code_descriptor != Object::null()) {
-    if (code_descriptor->IsCode()) {
-      CodePtr code = static_cast<CodePtr>(code_descriptor);
-      ASSERT(*code_start == Code::PayloadStartOf(code));
-      return code->untag()->compressed_stackmaps();
-    } else {
-      ASSERT(code_descriptor->IsCompressedStackMaps());
-      return static_cast<CompressedStackMapsPtr>(code_descriptor);
-    }
-  }
-
-  *code_start = 0;
-  return CompressedStackMaps::null();
+  return FindCode(group, pc, is_return_address);
 }
 
 }  // namespace dart
diff --git a/runtime/vm/reverse_pc_lookup_cache.h b/runtime/vm/reverse_pc_lookup_cache.h
index e214747..21aef18 100644
--- a/runtime/vm/reverse_pc_lookup_cache.h
+++ b/runtime/vm/reverse_pc_lookup_cache.h
@@ -7,6 +7,7 @@
 
 #include "vm/allocation.h"
 #include "vm/globals.h"
+#include "vm/raw_object.h"
 #include "vm/tagged_pointer.h"
 
 namespace dart {
@@ -22,24 +23,27 @@
   // given isolate |group| and vm isolate group.
   static CodePtr Lookup(IsolateGroup* group, uword pc, bool is_return_address);
 
-  // Looks for CompressedStackMaps corresponding to |pc| in the
-  // given isolate |group| and vm isolate group.
-  // Sets |code_start| to the beginning of the instructions corresponding
-  // to |pc| (like Code::PayloadStart()).
-  static CompressedStackMapsPtr FindCompressedStackMaps(IsolateGroup* group,
-                                                        uword pc,
-                                                        bool is_return_address,
-                                                        uword* code_start);
+  static const UntaggedCompressedStackMaps::Payload* FindStackMap(
+      IsolateGroup* group,
+      uword pc,
+      bool is_return_address,
+      uword* code_start,
+      const UntaggedCompressedStackMaps::Payload** global_table);
 
  private:
-  static ObjectPtr FindCodeDescriptorInGroup(IsolateGroup* group,
-                                             uword pc,
-                                             bool is_return_address,
-                                             uword* code_start);
-  static ObjectPtr FindCodeDescriptor(IsolateGroup* group,
-                                      uword pc,
-                                      bool is_return_address,
-                                      uword* code_start);
+  static const UntaggedCompressedStackMaps::Payload* FindStackMapInGroup(
+      IsolateGroup* group,
+      uword pc,
+      bool is_return_address,
+      uword* code_start,
+      const UntaggedCompressedStackMaps::Payload** global_table);
+
+  static CodePtr FindCodeInGroup(IsolateGroup* group,
+                                 uword pc,
+                                 bool is_return_address);
+  static CodePtr FindCode(IsolateGroup* group,
+                          uword pc,
+                          bool is_return_address);
 };
 
 }  // namespace dart
diff --git a/runtime/vm/service.h b/runtime/vm/service.h
index c31b191..f625b94 100644
--- a/runtime/vm/service.h
+++ b/runtime/vm/service.h
@@ -15,7 +15,7 @@
 namespace dart {
 
 #define SERVICE_PROTOCOL_MAJOR_VERSION 3
-#define SERVICE_PROTOCOL_MINOR_VERSION 54
+#define SERVICE_PROTOCOL_MINOR_VERSION 55
 
 class Array;
 class EmbedderServiceHandler;
diff --git a/runtime/vm/service/service.md b/runtime/vm/service/service.md
index 6a04228..2c22e5f 100644
--- a/runtime/vm/service/service.md
+++ b/runtime/vm/service/service.md
@@ -1,8 +1,8 @@
-# Dart VM Service Protocol 3.54
+# Dart VM Service Protocol 3.55
 
 > Please post feedback to the [observatory-discuss group][discuss-list]
 
-This document describes of _version 3.54_ of the Dart VM Service Protocol. This
+This document describes of _version 3.55_ of the Dart VM Service Protocol. This
 protocol is used to communicate with a running Dart Virtual Machine.
 
 To use the Service Protocol, start the VM with the *--observe* flag.
@@ -79,6 +79,7 @@
   - [setVMName](#setvmname)
   - [setVMTimelineFlags](#setvmtimelineflags)
   - [streamCancel](#streamcancel)
+  - [streamCpuSamplesWithUserTag](#streamcpusampleswithusertag)
   - [streamListen](#streamlisten)
 - [Public Types](#public-types)
   - [AllocationProfile](#allocationprofile)
@@ -1536,6 +1537,19 @@
 
 See [Success](#success).
 
+### streamCpuSamplesWithUserTag
+
+```
+Success streamCpuSamplesWithUserTag(string[] userTags)
+```
+
+The _streamCpuSamplesWithUserTag_ RPC allows for clients to specify which CPU
+samples collected by the profiler should be sent over the `Profiler` stream.
+When called, the VM will stream `CpuSamples` events containing `CpuSample`'s
+collected while a user tag contained in `userTags` was active.
+
+See [Success](#success).
+
 ### streamListen
 
 ```
@@ -4304,5 +4318,6 @@
 3.52 | Added `lookupResolvedPackageUris` and `lookupPackageUris` RPCs and `UriList` type.
 3.53 | Added `setIsolatePauseMode` RPC.
 3.54 | Added `CpuSamplesEvent`, updated `cpuSamples` property on `Event` to have type `CpuSamplesEvent`.
+3.55 | Added `streamCpuSamplesWithUserTag` RPC.
 
 [discuss-list]: https://groups.google.com/a/dartlang.org/forum/#!forum/observatory-discuss
diff --git a/runtime/vm/service_event.cc b/runtime/vm/service_event.cc
index 120a1dc..9e4f399 100644
--- a/runtime/vm/service_event.cc
+++ b/runtime/vm/service_event.cc
@@ -54,14 +54,14 @@
   // over the service.
   ASSERT(isolate_ != Dart::vm_isolate());
 
-  // System isolates should never post service events. However, the Isolate
+  // VM internal isolates should never post service events. However, the Isolate
   // service object uses a service event to represent the current running state
   // of the isolate, so we need to allow for system isolates to create resume
   // and none events for this purpose. The resume event represents a running
   // isolate and the none event is returned for an isolate that has not yet
   // been marked as runnable (see "pauseEvent" in Isolate::PrintJSON).
-  ASSERT(isolate == NULL || !Isolate::IsSystemIsolate(isolate) ||
-         (Isolate::IsSystemIsolate(isolate) &&
+  ASSERT(isolate == NULL || !Isolate::IsVMInternalIsolate(isolate) ||
+         (Isolate::IsVMInternalIsolate(isolate) &&
           (event_kind == ServiceEvent::kResume ||
            event_kind == ServiceEvent::kNone ||
            // VM service can print Observatory information to Stdout or Stderr
diff --git a/runtime/vm/service_test.cc b/runtime/vm/service_test.cc
index 2800565..751bb7e 100644
--- a/runtime/vm/service_test.cc
+++ b/runtime/vm/service_test.cc
@@ -105,16 +105,16 @@
 }
 
 static ArrayPtr EvalF(Dart_Handle lib, const char* fmt, ...) {
-  va_list args;
-  va_start(args, fmt);
-  intptr_t len = Utils::VSNPrint(NULL, 0, fmt, args);
-  va_end(args);
+  va_list messure_args;
+  va_start(messure_args, fmt);
+  intptr_t len = Utils::VSNPrint(NULL, 0, fmt, messure_args);
+  va_end(messure_args);
 
   char* buffer = Thread::Current()->zone()->Alloc<char>(len + 1);
-  va_list args2;
-  va_start(args2, fmt);
-  Utils::VSNPrint(buffer, (len + 1), fmt, args2);
-  va_end(args2);
+  va_list print_args;
+  va_start(print_args, fmt);
+  Utils::VSNPrint(buffer, (len + 1), fmt, print_args);
+  va_end(print_args);
 
   return Eval(lib, buffer);
 }
diff --git a/runtime/vm/simulator_arm.cc b/runtime/vm/simulator_arm.cc
index 6b52eae..8dd8013 100644
--- a/runtime/vm/simulator_arm.cc
+++ b/runtime/vm/simulator_arm.cc
@@ -916,25 +916,21 @@
 
 // Accessors for VFP register state.
 DART_FORCE_INLINE void Simulator::set_sregister(SRegister reg, float value) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT((reg >= 0) && (reg < kNumberOfSRegisters));
   sregisters_[reg] = bit_cast<int32_t, float>(value);
 }
 
 DART_FORCE_INLINE float Simulator::get_sregister(SRegister reg) const {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT((reg >= 0) && (reg < kNumberOfSRegisters));
   return bit_cast<float, int32_t>(sregisters_[reg]);
 }
 
 DART_FORCE_INLINE void Simulator::set_dregister(DRegister reg, double value) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT((reg >= 0) && (reg < kNumberOfDRegisters));
   dregisters_[reg] = bit_cast<int64_t, double>(value);
 }
 
 DART_FORCE_INLINE double Simulator::get_dregister(DRegister reg) const {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT((reg >= 0) && (reg < kNumberOfDRegisters));
   return bit_cast<double, int64_t>(dregisters_[reg]);
 }
@@ -958,25 +954,21 @@
 }
 
 void Simulator::set_sregister_bits(SRegister reg, int32_t value) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT((reg >= 0) && (reg < kNumberOfSRegisters));
   sregisters_[reg] = value;
 }
 
 int32_t Simulator::get_sregister_bits(SRegister reg) const {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT((reg >= 0) && (reg < kNumberOfSRegisters));
   return sregisters_[reg];
 }
 
 void Simulator::set_dregister_bits(DRegister reg, int64_t value) {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT((reg >= 0) && (reg < kNumberOfDRegisters));
   dregisters_[reg] = value;
 }
 
 int64_t Simulator::get_dregister_bits(DRegister reg) const {
-  ASSERT(TargetCPUFeatures::vfp_supported());
   ASSERT((reg >= 0) && (reg < kNumberOfDRegisters));
   return dregisters_[reg];
 }
@@ -1500,7 +1492,6 @@
         set_register(R3, icount_);
         set_register(IP, icount_);
         set_register(LR, icount_);
-        if (TargetCPUFeatures::vfp_supported()) {
           double zap_dvalue = static_cast<double>(icount_);
           // Do not zap D0, as it may contain a float result.
           for (int i = D1; i <= D7; i++) {
@@ -1513,7 +1504,6 @@
             set_dregister(static_cast<DRegister>(i), zap_dvalue);
           }
 #endif
-        }
 
         // Return.
         set_pc(saved_lr);
@@ -3519,7 +3509,6 @@
 
   // Setup parameters.
   if (fp_args) {
-    ASSERT(TargetCPUFeatures::vfp_supported());
     set_sregister(S0, bit_cast<float, int32_t>(parameter0));
     set_sregister(S1, bit_cast<float, int32_t>(parameter1));
     set_sregister(S2, bit_cast<float, int32_t>(parameter2));
@@ -3569,7 +3558,6 @@
   double d14_val = 0.0;
   double d15_val = 0.0;
 
-  if (TargetCPUFeatures::vfp_supported()) {
     d8_val = get_dregister(D8);
     d9_val = get_dregister(D9);
     d10_val = get_dregister(D10);
@@ -3578,7 +3566,6 @@
     d13_val = get_dregister(D13);
     d14_val = get_dregister(D14);
     d15_val = get_dregister(D15);
-  }
 
   // Setup the callee-saved registers with a known value. To be able to check
   // that they are preserved properly across dart execution.
@@ -3595,7 +3582,6 @@
   set_register(R11, callee_saved_value);
 
   double callee_saved_dvalue = 0.0;
-  if (TargetCPUFeatures::vfp_supported()) {
     callee_saved_dvalue = static_cast<double>(icount_);
     set_dregister(D8, callee_saved_dvalue);
     set_dregister(D9, callee_saved_dvalue);
@@ -3605,7 +3591,6 @@
     set_dregister(D13, callee_saved_dvalue);
     set_dregister(D14, callee_saved_dvalue);
     set_dregister(D15, callee_saved_dvalue);
-  }
 
   // Start the simulation
   Execute();
@@ -3622,7 +3607,6 @@
   ASSERT(callee_saved_value == get_register(R10));
   ASSERT(callee_saved_value == get_register(R11));
 
-  if (TargetCPUFeatures::vfp_supported()) {
     ASSERT(callee_saved_dvalue == get_dregister(D8));
     ASSERT(callee_saved_dvalue == get_dregister(D9));
     ASSERT(callee_saved_dvalue == get_dregister(D10));
@@ -3631,7 +3615,6 @@
     ASSERT(callee_saved_dvalue == get_dregister(D13));
     ASSERT(callee_saved_dvalue == get_dregister(D14));
     ASSERT(callee_saved_dvalue == get_dregister(D15));
-  }
 
   // Restore callee-saved registers with the original value.
   set_register(R4, r4_val);
@@ -3645,7 +3628,6 @@
   set_register(R10, r10_val);
   set_register(R11, r11_val);
 
-  if (TargetCPUFeatures::vfp_supported()) {
     set_dregister(D8, d8_val);
     set_dregister(D9, d9_val);
     set_dregister(D10, d10_val);
@@ -3654,13 +3636,11 @@
     set_dregister(D13, d13_val);
     set_dregister(D14, d14_val);
     set_dregister(D15, d15_val);
-  }
 
   // Restore the SP register and return R1:R0.
   set_register(SP, sp_before_call);
   int64_t return_value;
   if (fp_return) {
-    ASSERT(TargetCPUFeatures::vfp_supported());
     return_value = bit_cast<int64_t, double>(get_dregister(D0));
   } else {
     return_value = Utils::LowHighTo64Bits(get_register(R0), get_register(R1));
diff --git a/runtime/vm/source_report.cc b/runtime/vm/source_report.cc
index ebb4788..b826aa9 100644
--- a/runtime/vm/source_report.cc
+++ b/runtime/vm/source_report.cc
@@ -105,7 +105,7 @@
       return true;
   }
   if (func.is_abstract() || func.IsImplicitConstructor() ||
-      func.is_synthetic()) {
+      func.is_synthetic() || func.is_redirecting_factory()) {
     return true;
   }
   if (func.IsNonImplicitClosureFunction() &&
@@ -346,11 +346,14 @@
   const Array& coverage_array = Array::Handle(function.GetCoverageArray());
   if (!coverage_array.IsNull()) {
     for (intptr_t i = 0; i < coverage_array.Length(); i += 2) {
-      const TokenPosition token_pos = TokenPosition::Deserialize(
-          Smi::Value(Smi::RawCast(coverage_array.At(i))));
-      const bool was_executed =
-          Smi::Value(Smi::RawCast(coverage_array.At(i + 1))) != 0;
-      update_coverage(token_pos, was_executed);
+      bool is_branch_coverage;
+      const TokenPosition token_pos = TokenPosition::DecodeCoveragePosition(
+          Smi::Value(Smi::RawCast(coverage_array.At(i))), &is_branch_coverage);
+      if (!is_branch_coverage) {
+        const bool was_executed =
+            Smi::Value(Smi::RawCast(coverage_array.At(i + 1))) != 0;
+        update_coverage(token_pos, was_executed);
+      }
     }
   }
 
diff --git a/runtime/vm/source_report_test.cc b/runtime/vm/source_report_test.cc
index b21c588..2670ac6 100644
--- a/runtime/vm/source_report_test.cc
+++ b/runtime/vm/source_report_test.cc
@@ -1065,6 +1065,60 @@
       buffer);
 }
 
+ISOLATE_UNIT_TEST_CASE(SourceReport_Regress95008_RedirectingFactory) {
+  // WARNING: This MUST be big enough for the serialised JSON string.
+  const int kBufferSize = 1024;
+  char buffer[kBufferSize];
+  const char* kScript = R"(
+class A {
+  A();
+  factory A.foo(int i) = B; // LINE_A
+}
+
+class B extends A {
+  int i;
+  B(this.i); // LINE_B
+}
+
+main() {
+  A.foo(42);
+}
+)";
+
+  Library& lib = Library::Handle();
+  lib ^= ExecuteScript(kScript);
+  ASSERT(!lib.IsNull());
+  const Script& script =
+      Script::Handle(lib.LookupScript(String::Handle(String::New("test-lib"))));
+
+  SourceReport report(SourceReport::kCoverage);
+  JSONStream js;
+  report.PrintJSON(&js, script);
+  const char* json_str = js.ToCString();
+  ASSERT(strlen(json_str) < kBufferSize);
+  ElideJSONSubstring("classes", json_str, buffer);
+  ElideJSONSubstring("libraries", buffer, buffer);
+  EXPECT_STREQ(
+      "{\"type\":\"SourceReport\",\"ranges\":["
+
+      // A()
+      "{\"scriptIndex\":0,\"startPos\":13,\"endPos\":16,\"compiled\":true,"
+      "\"coverage\":{\"hits\":[13],\"misses\":[]}},"
+
+      // B()
+      "{\"scriptIndex\":0,\"startPos\":90,\"endPos\":99,\"compiled\":true,"
+      "\"coverage\":{\"hits\":[90],\"misses\":[]}},"
+
+      // main
+      "{\"scriptIndex\":0,\"startPos\":114,\"endPos\":136,\"compiled\":true,"
+      "\"coverage\":{\"hits\":[114,127],\"misses\":[]}}],"
+
+      // Only one script in the script table.
+      "\"scripts\":[{\"type\":\"@Script\",\"fixedId\":true,\"id\":\"\","
+      "\"uri\":\"file:\\/\\/\\/test-lib\",\"_kind\":\"kernel\"}]}",
+      buffer);
+}
+
 #endif  // !PRODUCT
 
 }  // namespace dart
diff --git a/runtime/vm/stack_frame.cc b/runtime/vm/stack_frame.cc
index e1fe0b4..55eebc9 100644
--- a/runtime/vm/stack_frame.cc
+++ b/runtime/vm/stack_frame.cc
@@ -205,13 +205,18 @@
   // helper functions to the raw object interface.
   NoSafepointScope no_safepoint;
   Code code;
-  CompressedStackMaps maps;
+
+  CompressedStackMaps::RawPayloadHandle maps;
+  CompressedStackMaps::RawPayloadHandle global_table;
+
   uword code_start;
 
   if (FLAG_precompiled_mode) {
-    maps = ReversePc::FindCompressedStackMaps(isolate_group(), pc(),
-                                              /*is_return_address=*/true,
-                                              &code_start);
+    const UntaggedCompressedStackMaps::Payload* global_table_payload;
+    maps = ReversePc::FindStackMap(isolate_group(), pc(),
+                                   /*is_return_address=*/true, &code_start,
+                                   &global_table_payload);
+    global_table = global_table_payload;
   } else {
     ObjectPtr pc_marker = *(reinterpret_cast<ObjectPtr*>(
         fp() + (runtime_frame_layout.code_from_fp * kWordSize)));
@@ -221,8 +226,12 @@
     if (pc_marker->IsHeapObject() && (pc_marker->GetClassId() == kCodeCid)) {
       code ^= pc_marker;
       code_start = code.PayloadStart();
+      ASSERT(code.compressed_stackmaps() != CompressedStackMaps::null());
       maps = code.compressed_stackmaps();
-      ASSERT(!maps.IsNull());
+      if (maps.UsesGlobalTable()) {
+        global_table =
+            isolate_group()->object_store()->canonicalized_stack_map_entries();
+      }
     } else {
       ASSERT(pc_marker == Object::null());
     }
@@ -231,11 +240,8 @@
   if (!maps.IsNull()) {
     // Optimized frames have a stack map. We need to visit the frame based
     // on the stack map.
-    CompressedStackMaps global_table;
-
-    global_table =
-        isolate_group()->object_store()->canonicalized_stack_map_entries();
-    CompressedStackMaps::Iterator it(maps, global_table);
+    CompressedStackMaps::Iterator<CompressedStackMaps::RawPayloadHandle> it(
+        maps, global_table);
     const uint32_t pc_offset = pc() - code_start;
     if (it.Find(pc_offset)) {
       ObjectPtr* first = reinterpret_cast<ObjectPtr*>(sp());
diff --git a/runtime/vm/symbols.h b/runtime/vm/symbols.h
index 50640ad..75bb968 100644
--- a/runtime/vm/symbols.h
+++ b/runtime/vm/symbols.h
@@ -16,6 +16,7 @@
 
 // One-character symbols are added implicitly.
 #define PREDEFINED_SYMBOLS_LIST(V)                                             \
+  V(AbiSpecificInteger, "AbiSpecificInteger")                                  \
   V(AbstractClassInstantiationError, "AbstractClassInstantiationError")        \
   V(AllocateInvocationMirror, "_allocateInvocationMirror")                     \
   V(AllocateInvocationMirrorForClosure, "_allocateInvocationMirrorForClosure") \
@@ -109,6 +110,7 @@
   V(ExternalOneByteString, "_ExternalOneByteString")                           \
   V(ExternalTwoByteString, "_ExternalTwoByteString")                           \
   V(FallThroughError, "FallThroughError")                                      \
+  V(FfiAbiSpecificMapping, "_FfiAbiSpecificMapping")                           \
   V(FfiBool, "Bool")                                                           \
   V(FfiCallback, "_FfiCallback")                                               \
   V(FfiDouble, "Double")                                                       \
@@ -124,6 +126,7 @@
   V(FfiIntPtr, "IntPtr")                                                       \
   V(FfiNativeFunction, "NativeFunction")                                       \
   V(FfiNativeType, "NativeType")                                               \
+  V(FfiNativeTypes, "nativeTypes")                                             \
   V(FfiPointer, "Pointer")                                                     \
   V(FfiStructLayout, "_FfiStructLayout")                                       \
   V(FfiStructLayoutArray, "_FfiInlineArray")                                   \
@@ -441,7 +444,6 @@
   V(current_position, ":current_position")                                     \
   V(dynamic_assert_assignable_stc_check,                                       \
     ":dynamic_assert_assignable_stc_check")                                    \
-  V(identityHashCode, "identityHashCode")                                      \
   V(index_temp, ":index_temp")                                                 \
   V(is_sync, ":is_sync")                                                       \
   V(isPaused, "isPaused")                                                      \
@@ -468,6 +470,7 @@
   V(vm_notify_debugger_on_exception, "vm:notify-debugger-on-exception")        \
   V(vm_recognized, "vm:recognized")                                            \
   V(vm_trace_entrypoints, "vm:testing.unsafe.trace-entrypoints-fn")            \
+  V(vm_ffi_abi_specific_mapping, "vm:ffi:abi-specific-mapping")                \
   V(vm_ffi_struct_fields, "vm:ffi:struct-fields")                              \
   V(vm_unsafe_no_interrupts, "vm:unsafe:no-interrupts")                        \
   V(vm_external_name, "vm:external-name")                                      \
diff --git a/runtime/vm/tags.cc b/runtime/vm/tags.cc
index ba981ee..483eaba 100644
--- a/runtime/vm/tags.cc
+++ b/runtime/vm/tags.cc
@@ -12,6 +12,9 @@
 
 namespace dart {
 
+MallocGrowableArray<const char*> UserTags::subscribed_tags_(4);
+Mutex* UserTags::subscribed_tags_lock_ = nullptr;
+
 const char* VMTag::TagName(uword tag) {
   if (IsNativeEntryTag(tag)) {
     const uint8_t* native_reverse_lookup = NativeEntry::ResolveSymbol(tag);
@@ -148,4 +151,55 @@
   return label.ToCString();
 }
 
+void UserTags::AddStreamableTagName(const char* tag) {
+  MutexLocker ml(subscribed_tags_lock_);
+  // Check this tag isn't already in the subscription list.
+  for (intptr_t i = 0; i < subscribed_tags_.length(); ++i) {
+    if (strcmp(tag, subscribed_tags_.At(i)) == 0) {
+      return;
+    }
+  }
+  subscribed_tags_.Add(strdup(tag));
+}
+
+void UserTags::RemoveStreamableTagName(const char* tag) {
+  MutexLocker ml(subscribed_tags_lock_);
+  bool found = false;
+  for (intptr_t i = 0; i < subscribed_tags_.length(); ++i) {
+    if (strcmp(tag, subscribed_tags_.At(i)) == 0) {
+      free(const_cast<char*>(subscribed_tags_.At(i)));
+      subscribed_tags_.RemoveAt(i);
+      found = true;
+      break;
+    }
+  }
+  ASSERT(found);
+}
+
+bool UserTags::IsTagNameStreamable(const char* tag) {
+  MutexLocker ml(subscribed_tags_lock_);
+  for (intptr_t i = 0; i < subscribed_tags_.length(); ++i) {
+    if (strcmp(tag, subscribed_tags_.At(i)) == 0) {
+      return true;
+    }
+  }
+  return false;
+}
+
+void UserTags::Init() {
+  subscribed_tags_lock_ = new Mutex();
+}
+
+void UserTags::Cleanup() {
+  {
+    MutexLocker ml(subscribed_tags_lock_);
+    for (intptr_t i = 0; i < subscribed_tags_.length(); ++i) {
+      free(const_cast<char*>(subscribed_tags_.At(i)));
+    }
+    subscribed_tags_.Clear();
+  }
+  delete subscribed_tags_lock_;
+  subscribed_tags_lock_ = nullptr;
+}
+
 }  // namespace dart
diff --git a/runtime/vm/tags.h b/runtime/vm/tags.h
index 8e270ab..5343096 100644
--- a/runtime/vm/tags.h
+++ b/runtime/vm/tags.h
@@ -5,7 +5,9 @@
 #ifndef RUNTIME_VM_TAGS_H_
 #define RUNTIME_VM_TAGS_H_
 
+#include "platform/growable_array.h"
 #include "vm/allocation.h"
+#include "vm/os_thread.h"
 #include "vm/thread_stack_resource.h"
 
 namespace dart {
@@ -113,6 +115,15 @@
     return (tag_id >= kUserTagIdOffset) &&
            (tag_id < kUserTagIdOffset + kMaxUserTags);
   }
+  static void AddStreamableTagName(const char* tag);
+  static void RemoveStreamableTagName(const char* tag);
+  static bool IsTagNameStreamable(const char* tag);
+  static void Init();
+  static void Cleanup();
+
+ private:
+  static Mutex* subscribed_tags_lock_;
+  static MallocGrowableArray<const char*> subscribed_tags_;
 };
 
 }  // namespace dart
diff --git a/runtime/vm/thread.cc b/runtime/vm/thread.cc
index 78feea8..6efc403 100644
--- a/runtime/vm/thread.cc
+++ b/runtime/vm/thread.cc
@@ -15,6 +15,7 @@
 #include "vm/message_handler.h"
 #include "vm/native_entry.h"
 #include "vm/object.h"
+#include "vm/object_store.h"
 #include "vm/os_thread.h"
 #include "vm/profiler.h"
 #include "vm/runtime_entry.h"
@@ -48,6 +49,8 @@
     delete api_reusable_scope_;
     api_reusable_scope_ = NULL;
   }
+
+  DO_IF_TSAN(delete tsan_utils_);
 }
 
 #if defined(DEBUG)
@@ -86,6 +89,7 @@
       api_top_scope_(NULL),
       double_truncate_round_supported_(
           TargetCPUFeatures::double_truncate_round_supported() ? 1 : 0),
+      tsan_utils_(DO_IF_TSAN(new TsanUtils()) DO_IF_NOT_TSAN(nullptr)),
       task_kind_(kUnknownTask),
       dart_stream_(NULL),
       thread_lock_(),
@@ -723,12 +727,28 @@
                                      ValidationPolicy::kDontValidateFrames,
                                      this, cross_thread_policy);
   RestoreWriteBarrierInvariantVisitor visitor(isolate_group(), this, op);
+  ObjectStore* object_store = isolate_group()->object_store();
   bool scan_next_dart_frame = false;
   for (StackFrame* frame = frames_iterator.NextFrame(); frame != NULL;
        frame = frames_iterator.NextFrame()) {
     if (frame->IsExitFrame()) {
       scan_next_dart_frame = true;
-    } else if (frame->IsDartFrame(/*validate=*/false)) {
+    } else if (frame->IsEntryFrame()) {
+      /* Continue searching. */
+    } else if (frame->IsStubFrame()) {
+      const uword pc = frame->pc();
+      if (Code::ContainsInstructionAt(
+              object_store->init_late_static_field_stub(), pc) ||
+          Code::ContainsInstructionAt(
+              object_store->init_late_final_static_field_stub(), pc) ||
+          Code::ContainsInstructionAt(
+              object_store->init_late_instance_field_stub(), pc) ||
+          Code::ContainsInstructionAt(
+              object_store->init_late_final_instance_field_stub(), pc)) {
+        scan_next_dart_frame = true;
+      }
+    } else {
+      ASSERT(frame->IsDartFrame(/*validate=*/false));
       if (scan_next_dart_frame) {
         frame->VisitObjectPointers(&visitor);
       }
diff --git a/runtime/vm/thread.h b/runtime/vm/thread.h
index 1eb3222..ed9e9b7 100644
--- a/runtime/vm/thread.h
+++ b/runtime/vm/thread.h
@@ -9,6 +9,8 @@
 #error "Should not include runtime"
 #endif
 
+#include <setjmp.h>
+
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/atomic.h"
@@ -198,6 +200,8 @@
   V(uword, deoptimize_entry_, StubCode::Deoptimize().EntryPoint(), 0)          \
   V(uword, call_native_through_safepoint_entry_point_,                         \
     StubCode::CallNativeThroughSafepoint().EntryPoint(), 0)                    \
+  V(uword, jump_to_frame_entry_point_, StubCode::JumpToFrame().EntryPoint(),   \
+    0)                                                                         \
   V(uword, slow_type_test_entry_point_, StubCode::SlowTypeTest().EntryPoint(), \
     0)
 
@@ -257,6 +261,35 @@
   kNumLevels,
 };
 
+// Accessed from generated code.
+struct TsanUtils {
+  // Used to allow unwinding runtime C frames using longjmp() when throwing
+  // exceptions. This allows triggering the normal TSAN shadow stack unwinding
+  // implementation.
+  // -> See https://dartbug.com/47472#issuecomment-948235479 for details.
+  void* setjmp_function = reinterpret_cast<void*>(&setjmp);
+  jmp_buf* setjmp_buffer = nullptr;
+  uword exception_pc = 0;
+  uword exception_sp = 0;
+  uword exception_fp = 0;
+
+  static intptr_t setjmp_function_offset() {
+    return OFFSET_OF(TsanUtils, setjmp_function);
+  }
+  static intptr_t setjmp_buffer_offset() {
+    return OFFSET_OF(TsanUtils, setjmp_buffer);
+  }
+  static intptr_t exception_pc_offset() {
+    return OFFSET_OF(TsanUtils, exception_pc);
+  }
+  static intptr_t exception_sp_offset() {
+    return OFFSET_OF(TsanUtils, exception_sp);
+  }
+  static intptr_t exception_fp_offset() {
+    return OFFSET_OF(TsanUtils, exception_fp);
+  }
+};
+
 // A VM thread; may be executing Dart code or performing helper tasks like
 // garbage collection or compilation. The Thread structure associated with
 // a thread is allocated by EnsureInit before entering an isolate, and destroyed
@@ -441,6 +474,13 @@
     return OFFSET_OF(Thread, double_truncate_round_supported_);
   }
 
+  static intptr_t tsan_utils_offset() { return OFFSET_OF(Thread, tsan_utils_); }
+
+#if defined(USING_THREAD_SANITIZER)
+  uword exit_through_ffi() const { return exit_through_ffi_; }
+  TsanUtils* tsan_utils() const { return tsan_utils_; }
+#endif  // defined(USING_THREAD_SANITIZER)
+
   // The isolate that this thread is operating on, or nullptr if none.
   Isolate* isolate() const { return isolate_; }
   static intptr_t isolate_offset() { return OFFSET_OF(Thread, isolate_); }
@@ -990,6 +1030,7 @@
   void InitVMConstants();
 
   Random* random() { return &thread_random_; }
+  static intptr_t random_offset() { return OFFSET_OF(Thread, thread_random_); }
 
   uint64_t* GetFfiMarshalledArguments(intptr_t size) {
     if (ffi_marshalled_arguments_size_ < size) {
@@ -1098,6 +1139,9 @@
   uword exit_through_ffi_ = 0;
   ApiLocalScope* api_top_scope_;
   uint8_t double_truncate_round_supported_;
+  ALIGN8 Random thread_random_;
+
+  TsanUtils* tsan_utils_ = nullptr;
 
   // ---- End accessed from generated code. ----
 
@@ -1135,8 +1179,6 @@
 
   ErrorPtr sticky_error_;
 
-  Random thread_random_;
-
   intptr_t ffi_marshalled_arguments_size_ = 0;
   uint64_t* ffi_marshalled_arguments_;
 
diff --git a/runtime/vm/timeline.cc b/runtime/vm/timeline.cc
index 386178e..13f4ab9 100644
--- a/runtime/vm/timeline.cc
+++ b/runtime/vm/timeline.cc
@@ -349,14 +349,16 @@
                                             va_list args) {
   ASSERT(i >= 0);
   ASSERT(i < length_);
-  va_list args2;
-  va_copy(args2, args);
-  intptr_t len = Utils::VSNPrint(NULL, 0, fmt, args);
-  va_end(args);
+  va_list measure_args;
+  va_copy(measure_args, args);
+  intptr_t len = Utils::VSNPrint(NULL, 0, fmt, measure_args);
+  va_end(measure_args);
 
   char* buffer = reinterpret_cast<char*>(malloc(len + 1));
-  Utils::VSNPrint(buffer, (len + 1), fmt, args2);
-  va_end(args2);
+  va_list print_args;
+  va_copy(print_args, args);
+  Utils::VSNPrint(buffer, (len + 1), fmt, print_args);
+  va_end(print_args);
 
   SetArgument(i, name, buffer);
 }
@@ -546,6 +548,7 @@
   va_list args;
   va_start(args, fmt);
   arguments_.FormatArgument(i, name, fmt, args);
+  va_end(args);
 }
 
 void TimelineEvent::Complete() {
@@ -846,6 +849,7 @@
   va_list args;
   va_start(args, fmt);
   arguments_.FormatArgument(i, name, fmt, args);
+  va_end(args);
 }
 
 void TimelineEventScope::StealArguments(TimelineEvent* event) {
diff --git a/runtime/vm/token_position.cc b/runtime/vm/token_position.cc
index 14f7058..88b27c1 100644
--- a/runtime/vm/token_position.cc
+++ b/runtime/vm/token_position.cc
@@ -21,6 +21,19 @@
   return static_cast<int32_t>(value_);
 }
 
+intptr_t TokenPosition::EncodeCoveragePosition(bool is_branch_coverage) {
+  // Normal coverage positions are encoded as 2 * pos, and branch coverage are
+  // encoded as 2 * pos + 1.
+  intptr_t encoded_position = 2 * static_cast<intptr_t>(value_);
+  return is_branch_coverage ? encoded_position + 1 : encoded_position;
+}
+
+TokenPosition TokenPosition::DecodeCoveragePosition(intptr_t encoded_position,
+                                                    bool* is_branch_coverage) {
+  *is_branch_coverage = ((encoded_position % 2) == 1);
+  return TokenPosition(encoded_position / 2);
+}
+
 #define DEFINE_VALUES(name, value)                                             \
   const TokenPosition TokenPosition::k##name(value);
 SENTINEL_TOKEN_DESCRIPTORS(DEFINE_VALUES);
diff --git a/runtime/vm/token_position.h b/runtime/vm/token_position.h
index 8dcf100..6778726 100644
--- a/runtime/vm/token_position.h
+++ b/runtime/vm/token_position.h
@@ -202,6 +202,13 @@
     return TokenPosition((kLastPos - 1) - value);
   }
 
+  // Encode the token position for storage in the coverage array.
+  intptr_t EncodeCoveragePosition(bool is_branch_coverage);
+
+  // Decode a token position that was stored in the coverage array.
+  static TokenPosition DecodeCoveragePosition(intptr_t encoded_position,
+                                              bool* is_branch_coverage);
+
   const char* ToCString() const;
 
  private:
diff --git a/runtime/vm/unit_test.cc b/runtime/vm/unit_test.cc
index e96548eb7..a2478ad 100644
--- a/runtime/vm/unit_test.cc
+++ b/runtime/vm/unit_test.cc
@@ -667,7 +667,7 @@
   return Api::NewHandle(thread, val.ptr());
 }
 
-#if !defined(PRODUCT)
+#if !defined(PRODUCT) && defined(TARGET_ARCH_IA32)
 static bool IsHex(int c) {
   return ('0' <= c && c <= '9') || ('a' <= c && c <= 'f');
 }
@@ -695,6 +695,8 @@
   code_.set_owner(function);
   code_.set_exception_handlers(Object::empty_exception_handlers());
 #ifndef PRODUCT
+  // Disassemble relative since code addresses are not stable from run to run.
+  SetFlagScope<bool> sfs(&FLAG_disassemble_relative, true);
   uword start = code_.PayloadStart();
   if (FLAG_disassemble) {
     OS::PrintErr("Code for test '%s' {\n", name_);
@@ -703,7 +705,9 @@
   }
   Disassembler::Disassemble(start, start + assembler_->CodeSize(), disassembly_,
                             DISASSEMBLY_SIZE);
-  // Blank out big hex constants, since they are not stable from run to run.
+#if defined(TARGET_ARCH_IA32)
+  // Blank out absolute addressing constants, since they are not stable from run
+  // to run.
   bool in_hex_constant = false;
   for (char* p = disassembly_; *p != '\0'; p++) {
     if (in_hex_constant) {
@@ -713,13 +717,14 @@
         in_hex_constant = false;
       }
     } else {
-      if (*p == '0' && *(p + 1) == 'x' && IsHex(*(p + 2)) && IsHex(*(p + 3)) &&
+      if (*p == '[' && *(p + 1) == '0' && *(p + 2) == 'x' && IsHex(*(p + 3)) &&
           IsHex(*(p + 4))) {
-        p++;
+        p += 2;
         in_hex_constant = true;
       }
     }
   }
+#endif  // TARGET_ARCH_IA32
 #endif  // !PRODUCT
 }
 
diff --git a/runtime/vm/unit_test.h b/runtime/vm/unit_test.h
index 7bc9f23..bc86b9e 100644
--- a/runtime/vm/unit_test.h
+++ b/runtime/vm/unit_test.h
@@ -587,8 +587,8 @@
   // Assemble test and set code_.
   void Assemble();
 
-  // Disassembly of the code with large constants blanked out.
-  char* BlankedDisassembly() { return disassembly_; }
+  // Disassembly of the code with relative branch/jump targets.
+  char* RelativeDisassembly() { return disassembly_; }
 
  private:
   const char* name_;
diff --git a/runtime/vm/v8_snapshot_writer.cc b/runtime/vm/v8_snapshot_writer.cc
index 1a224df..2aaf1cb 100644
--- a/runtime/vm/v8_snapshot_writer.cc
+++ b/runtime/vm/v8_snapshot_writer.cc
@@ -279,6 +279,7 @@
   va_list args;
   va_start(args, fmt);
   const char* str = OS::VSCreate(zone_, fmt, args);
+  va_end(args);
   if (auto const kv = index_map_.Lookup(str)) {
     return kv->value;
   }
diff --git a/runtime/vm/virtual_memory_posix.cc b/runtime/vm/virtual_memory_posix.cc
index b2717df..72235ff 100644
--- a/runtime/vm/virtual_memory_posix.cc
+++ b/runtime/vm/virtual_memory_posix.cc
@@ -138,7 +138,7 @@
         nullptr, PROT_NONE, allocated_size, kCompressedHeapPageSize,
         allocated_size + kCompressedHeapPageSize,
         MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE);
-    if (address == MAP_FAILED) continue;
+    if (address == nullptr) continue;
 
     MemoryRegion region(address, allocated_size);
     region = ClipToAlignedRegion(region, kCompressedHeapAlignment);
diff --git a/sdk/bin/dartdoc b/sdk/bin/dartdoc
index e9584c1..b7817c8 100755
--- a/sdk/bin/dartdoc
+++ b/sdk/bin/dartdoc
@@ -3,6 +3,8 @@
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
+echo "Warning: 'dartdoc' is deprecated. Please use 'dart doc'." 1>&2
+
 function follow_links() {
   file="$1"
   while [ -h "$file" ]; do
@@ -23,4 +25,4 @@
 
 # We are running the snapshot in the built SDK.
 DART="$BIN_DIR/dart"
-exec "$DART" "--packages=$BIN_DIR/resources/dartdoc/.packages" "$SNAPSHOT" "$@"
+exec "$DART" "--packages=$BIN_DIR/resources/dartdoc/.packages" "$SNAPSHOT" "--resources-dir=$BIN_DIR/resources/dartdoc/resources/" "$@"
diff --git a/sdk/bin/dartdoc.bat b/sdk/bin/dartdoc.bat
index 876eb0e..ea32a87 100644
--- a/sdk/bin/dartdoc.bat
+++ b/sdk/bin/dartdoc.bat
@@ -3,6 +3,8 @@
 REM for details. All rights reserved. Use of this source code is governed by a
 REM BSD-style license that can be found in the LICENSE file.
 
+echo Warning: 'dartdoc' is deprecated. Please use 'dart doc'. 1>&2
+
 setlocal
 rem Handle the case where dart-sdk/bin has been symlinked to.
 set DIR_NAME_WITH_SLASH=%~dp0
diff --git a/sdk/lib/_internal/js_dev_runtime/patch/io_patch.dart b/sdk/lib/_internal/js_dev_runtime/patch/io_patch.dart
index 4960213..413116c 100644
--- a/sdk/lib/_internal/js_dev_runtime/patch/io_patch.dart
+++ b/sdk/lib/_internal/js_dev_runtime/patch/io_patch.dart
@@ -475,13 +475,13 @@
 class RawSocket {
   @patch
   static Future<RawSocket> connect(dynamic host, int port,
-      {dynamic sourceAddress, Duration? timeout}) {
+      {dynamic sourceAddress, int sourcePort = 0, Duration? timeout}) {
     throw UnsupportedError("RawSocket constructor");
   }
 
   @patch
   static Future<ConnectionTask<RawSocket>> startConnect(dynamic host, int port,
-      {dynamic sourceAddress}) {
+      {dynamic sourceAddress, int sourcePort = 0}) {
     throw UnsupportedError("RawSocket constructor");
   }
 }
@@ -490,13 +490,13 @@
 class Socket {
   @patch
   static Future<Socket> _connect(dynamic host, int port,
-      {dynamic sourceAddress, Duration? timeout}) {
+      {dynamic sourceAddress, int sourcePort = 0, Duration? timeout}) {
     throw UnsupportedError("Socket constructor");
   }
 
   @patch
   static Future<ConnectionTask<Socket>> _startConnect(dynamic host, int port,
-      {dynamic sourceAddress}) {
+      {dynamic sourceAddress, int sourcePort = 0}) {
     throw UnsupportedError("Socket constructor");
   }
 }
diff --git a/sdk/lib/_internal/js_dev_runtime/patch/js_patch.dart b/sdk/lib/_internal/js_dev_runtime/patch/js_patch.dart
index 033b303..96a972f 100644
--- a/sdk/lib/_internal/js_dev_runtime/patch/js_patch.dart
+++ b/sdk/lib/_internal/js_dev_runtime/patch/js_patch.dart
@@ -9,7 +9,7 @@
 
 import 'dart:_js_helper' show patch, NoReifyGeneric, Primitives;
 import 'dart:_foreign_helper' show JS;
-import 'dart:_interceptors' show JavaScriptObject;
+import 'dart:_interceptors' show LegacyJavaScriptObject;
 import 'dart:_runtime' as dart;
 
 @patch
@@ -368,7 +368,8 @@
     int ms = JS('!', '#.getTime()', o);
     return DateTime.fromMillisecondsSinceEpoch(ms);
   } else if (o is _DartObject &&
-      !identical(dart.getReifiedType(o), dart.typeRep<JavaScriptObject>())) {
+      !identical(
+          dart.getReifiedType(o), dart.typeRep<LegacyJavaScriptObject>())) {
     return o._dartObj;
   } else {
     return _wrapToDart(o);
diff --git a/sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/rtti.dart b/sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/rtti.dart
index 9e99b26..f359d52 100644
--- a/sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/rtti.dart
+++ b/sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/rtti.dart
@@ -92,13 +92,13 @@
         return JS('', '#.constructor', obj);
       }
       var result = JS('', '#[#]', obj, _extensionType);
-      if (result == null) return typeRep<JavaScriptObject>();
+      if (result == null) return typeRep<LegacyJavaScriptObject>();
       return result;
     case "function":
       // All Dart functions and callable classes must set _runtimeType
       var result = JS('', '#[#]', obj, _runtimeType);
       if (result != null) return result;
-      return typeRep<JavaScriptObject>();
+      return typeRep<LegacyJavaScriptObject>();
     case "undefined":
       return JS('', '#', Null);
     case "number":
@@ -109,7 +109,7 @@
       return JS('', '#', String);
     case "symbol":
     default:
-      return typeRep<JavaScriptObject>();
+      return typeRep<LegacyJavaScriptObject>();
   }
 }
 
diff --git a/sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/runtime.dart b/sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/runtime.dart
index c5881ab..af599c3 100644
--- a/sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/runtime.dart
+++ b/sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/runtime.dart
@@ -11,7 +11,7 @@
 import 'dart:_debugger' show stackTraceMapper, trackCall;
 import 'dart:_foreign_helper' show JS, JSExportName, rest, spread;
 import 'dart:_interceptors'
-    show JSArray, jsNull, JSFunction, NativeError, JavaScriptObject;
+    show JSArray, jsNull, JSFunction, NativeError, LegacyJavaScriptObject;
 import 'dart:_internal' as internal show LateError, Symbol;
 import 'dart:_js_helper'
     show
diff --git a/sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/types.dart b/sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/types.dart
index 9904b5c..9452ed3 100644
--- a/sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/types.dart
+++ b/sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/types.dart
@@ -164,7 +164,7 @@
 
 @notNull
 bool _isJsObject(obj) =>
-    JS('!', '# === #', getReifiedType(obj), typeRep<JavaScriptObject>());
+    JS('!', '# === #', getReifiedType(obj), typeRep<LegacyJavaScriptObject>());
 
 /// Asserts that [f] is a native JS functions and returns it if so.
 ///
@@ -1503,16 +1503,17 @@
     }
 
     // Even though lazy and anonymous JS types are natural subtypes of
-    // JavaScriptObject, JS types should be treated as mutual subtypes of each
-    // other. This allows users to be able to interface with both extension
-    // types on JavaScriptObject and package:js using the same object.
+    // LegacyJavaScriptObject, JS types should be treated as mutual subtypes of
+    // each other. This allows users to be able to interface with both extension
+    // types on LegacyJavaScriptObject and package:js using the same object.
     //
     // Therefore, the following relationships hold true:
     //
-    // JavaScriptObject <: package:js types
-    // package:js types <: JavaScriptObject
+    // LegacyJavaScriptObject <: package:js types
+    // package:js types <: LegacyJavaScriptObject
 
-    if (_isInterfaceSubtype(t1, typeRep<JavaScriptObject>(), strictMode) &&
+    if (_isInterfaceSubtype(
+            t1, typeRep<LegacyJavaScriptObject>(), strictMode) &&
         // TODO: Since package:js types are instances of PackageJSType and
         // we don't have a mechanism to determine if *some* package:js type
         // implements t2. This will possibly require keeping a map of these
@@ -1522,7 +1523,8 @@
       return true;
     }
 
-    if (_isInterfaceSubtype(typeRep<JavaScriptObject>(), t2, strictMode) &&
+    if (_isInterfaceSubtype(
+            typeRep<LegacyJavaScriptObject>(), t2, strictMode) &&
         _isInterfaceSubtype(t1, _pkgJSTypeForSubtyping, strictMode)) {
       return true;
     }
diff --git a/sdk/lib/_internal/js_dev_runtime/private/interceptors.dart b/sdk/lib/_internal/js_dev_runtime/private/interceptors.dart
index 01921c0..8e700e5 100644
--- a/sdk/lib/_internal/js_dev_runtime/private/interceptors.dart
+++ b/sdk/lib/_internal/js_dev_runtime/private/interceptors.dart
@@ -81,14 +81,21 @@
 /// interop library.
 abstract class JSObject {}
 
+/// Superclass of all interop objects and native types defined in the web
+/// libraries.
+///
+/// This is the class static interop classes erase to and the class interop
+/// extension types should use as the on-type.
+class JavaScriptObject extends Interceptor {
+  const JavaScriptObject();
+}
+
 /// Interceptor base class for JavaScript objects not recognized as some more
 /// specific native type.
-
-/// Unlike dart2js, ddc does not intercept JS objects, so this is only used as
-/// an on-type for JS interop extension types. All JS interop objects should be
-/// castable to this type.
-abstract class JavaScriptObject extends Interceptor implements JSObject {
-  const JavaScriptObject();
+///
+/// Note that this used to be `JavaScriptObject`.
+class LegacyJavaScriptObject extends JavaScriptObject implements JSObject {
+  const LegacyJavaScriptObject();
 }
 
 /// Interceptor for plain JavaScript objects created as JavaScript object
@@ -96,7 +103,7 @@
 ///
 /// Note that this isn't being used today in ddc. Instead of using interceptors,
 /// we have other type logic to distinguish JS types.
-class PlainJavaScriptObject extends JavaScriptObject {
+class PlainJavaScriptObject extends LegacyJavaScriptObject {
   const PlainJavaScriptObject();
 }
 
@@ -106,7 +113,7 @@
 /// This class also serves as a fallback for unknown JavaScript exceptions.
 /// Note that this isn't being used today in ddc. Instead of using interceptors,
 /// we have other type logic to distinguish JS types.
-class UnknownJavaScriptObject extends JavaScriptObject {
+class UnknownJavaScriptObject extends LegacyJavaScriptObject {
   const UnknownJavaScriptObject();
 }
 
diff --git a/sdk/lib/_internal/js_runtime/lib/interceptors.dart b/sdk/lib/_internal/js_runtime/lib/interceptors.dart
index 5a062ab..bda0ac3 100644
--- a/sdk/lib/_internal/js_runtime/lib/interceptors.dart
+++ b/sdk/lib/_internal/js_runtime/lib/interceptors.dart
@@ -399,16 +399,28 @@
   operator []=(int index, E value);
 }
 
-/// The interface implemented by JavaScript objects.  These are methods in
-/// addition to the regular Dart Object methods like [Object.hashCode].
+/// The interface implemented by JavaScript objects.
 ///
-/// This is the type that should be exported by a JavaScript interop library.
+/// These are methods in addition to the regular Dart Object methods like
+/// [Object.hashCode]. This is the type that should be exported by a JavaScript
+/// interop library.
 abstract class JSObject {}
 
+/// Superclass of all interop objects and native types defined in the web
+/// libraries.
+///
+/// This is the class static interop classes erase to and the class interop
+/// extension types should use as the on-type.
+class JavaScriptObject extends Interceptor {
+  const JavaScriptObject();
+}
+
 /// Interceptor base class for JavaScript objects not recognized as some more
 /// specific native type.
-class JavaScriptObject extends Interceptor implements JSObject {
-  const JavaScriptObject();
+///
+/// Note that this used to be `JavaScriptObject`.
+class LegacyJavaScriptObject extends JavaScriptObject implements JSObject {
+  const LegacyJavaScriptObject();
 
   // It would be impolite to stash a property on the object.
   int get hashCode => 0;
@@ -421,7 +433,7 @@
 
 /// Interceptor for plain JavaScript objects created as JavaScript object
 /// literals or `new Object()`.
-class PlainJavaScriptObject extends JavaScriptObject {
+class PlainJavaScriptObject extends LegacyJavaScriptObject {
   const PlainJavaScriptObject();
 }
 
@@ -429,7 +441,7 @@
 /// non-trivial prototype chain.
 ///
 /// This class also serves as a fallback for unknown JavaScript exceptions.
-class UnknownJavaScriptObject extends JavaScriptObject {
+class UnknownJavaScriptObject extends LegacyJavaScriptObject {
   const UnknownJavaScriptObject();
 }
 
@@ -437,7 +449,7 @@
 /// been converted to JavaScript functions.
 /// These interceptor methods are not always used as the JavaScript function
 /// object has also been mangled to support Dart function calling conventions.
-class JavaScriptFunction extends JavaScriptObject implements Function {
+class JavaScriptFunction extends LegacyJavaScriptObject implements Function {
   const JavaScriptFunction();
 
   String toString() {
diff --git a/sdk/lib/_internal/js_runtime/lib/io_patch.dart b/sdk/lib/_internal/js_runtime/lib/io_patch.dart
index 6a88d0f..ae50e7b 100644
--- a/sdk/lib/_internal/js_runtime/lib/io_patch.dart
+++ b/sdk/lib/_internal/js_runtime/lib/io_patch.dart
@@ -475,13 +475,13 @@
 class RawSocket {
   @patch
   static Future<RawSocket> connect(dynamic host, int port,
-      {dynamic sourceAddress, Duration? timeout}) {
+      {dynamic sourceAddress, int sourcePort = 0, Duration? timeout}) {
     throw new UnsupportedError("RawSocket constructor");
   }
 
   @patch
   static Future<ConnectionTask<RawSocket>> startConnect(dynamic host, int port,
-      {dynamic sourceAddress}) {
+      {dynamic sourceAddress, int sourcePort = 0}) {
     throw new UnsupportedError("RawSocket constructor");
   }
 }
@@ -490,13 +490,13 @@
 class Socket {
   @patch
   static Future<Socket> _connect(dynamic host, int port,
-      {dynamic sourceAddress, Duration? timeout}) {
+      {dynamic sourceAddress, int sourcePort = 0, Duration? timeout}) {
     throw new UnsupportedError("Socket constructor");
   }
 
   @patch
   static Future<ConnectionTask<Socket>> _startConnect(dynamic host, int port,
-      {dynamic sourceAddress}) {
+      {dynamic sourceAddress, int sourcePort = 0}) {
     throw new UnsupportedError("Socket constructor");
   }
 }
diff --git a/sdk/lib/_internal/vm/bin/socket_patch.dart b/sdk/lib/_internal/vm/bin/socket_patch.dart
index 8812068..d681626 100644
--- a/sdk/lib/_internal/vm/bin/socket_patch.dart
+++ b/sdk/lib/_internal/vm/bin/socket_patch.dart
@@ -17,14 +17,14 @@
 class RawSocket {
   @patch
   static Future<RawSocket> connect(dynamic host, int port,
-      {dynamic sourceAddress, Duration? timeout}) {
-    return _RawSocket.connect(host, port, sourceAddress, timeout);
+      {dynamic sourceAddress, int sourcePort = 0, Duration? timeout}) {
+    return _RawSocket.connect(host, port, sourceAddress, sourcePort, timeout);
   }
 
   @patch
   static Future<ConnectionTask<RawSocket>> startConnect(dynamic host, int port,
-      {dynamic sourceAddress}) {
-    return _RawSocket.startConnect(host, port, sourceAddress);
+      {dynamic sourceAddress, int sourcePort = 0}) {
+    return _RawSocket.startConnect(host, port, sourceAddress, sourcePort);
   }
 }
 
@@ -654,7 +654,7 @@
   }
 
   static Future<ConnectionTask<_NativeSocket>> startConnect(
-      dynamic host, int port, dynamic sourceAddress) {
+      dynamic host, int port, dynamic sourceAddress, int sourcePort) {
     // Looks up [sourceAddress] to one or more IP addresses,
     // then tries connecting to each one until a connection succeeds.
     // Attempts are staggered by a minimum delay, so a new
@@ -666,6 +666,7 @@
       host = escapeLinkLocalAddress(host);
     }
     _throwOnBadPort(port);
+    _throwOnBadPort(sourcePort);
     _InternetAddress? source;
     if (sourceAddress != null) {
       if (sourceAddress is _InternetAddress) {
@@ -682,7 +683,7 @@
 
     return new Future.value(host).then<ConnectionTask<_NativeSocket>>((host) {
       if (host is _InternetAddress) {
-        return tryConnectToResolvedAddresses(host, port, source,
+        return tryConnectToResolvedAddresses(host, port, source, sourcePort,
             Stream.value(<_InternetAddress>[host]), stackTrace);
       }
       final hostname = host as String;
@@ -700,7 +701,7 @@
               : lookupAsStream(hostname);
 
       return tryConnectToResolvedAddresses(
-          host, port, source, stream, stackTrace);
+          host, port, source, sourcePort, stream, stackTrace);
     });
   }
 
@@ -708,6 +709,7 @@
       dynamic host,
       int port,
       _InternetAddress? source,
+      int sourcePort,
       Stream<List<InternetAddress>> addresses,
       StackTrace callerStackTrace) {
     // Completer for result.
@@ -758,10 +760,16 @@
             connectionResult is OSError);
       } else {
         final address_ = address as _InternetAddress;
-        if (source == null) {
+        if (source == null && sourcePort == 0) {
           connectionResult = socket.nativeCreateConnect(
               address_._in_addr, port, address_._scope_id);
         } else {
+          // allow specified port without address
+          if (source == null) {
+            source = address_.type == InternetAddressType.IPv4
+                ? _InternetAddress.anyIPv4
+                : _InternetAddress.anyIPv6;
+          }
           if (source.type != InternetAddressType.IPv4 &&
               source.type != InternetAddressType.IPv6) {
             return SocketException(
@@ -773,8 +781,8 @@
                 "${InternetAddressType.IPv6} but was ${source.type}",
                 address: address);
           }
-          connectionResult = socket.nativeCreateBindConnect(
-              address_._in_addr, port, source._in_addr, address_._scope_id);
+          connectionResult = socket.nativeCreateBindConnect(address_._in_addr,
+              port, source._in_addr, sourcePort, address_._scope_id);
         }
         assert(connectionResult == true || connectionResult is OSError);
       }
@@ -935,9 +943,9 @@
     return new ConnectionTask<_NativeSocket>._(result.future, onCancel);
   }
 
-  static Future<_NativeSocket> connect(
-      dynamic host, int port, dynamic sourceAddress, Duration? timeout) {
-    return startConnect(host, port, sourceAddress)
+  static Future<_NativeSocket> connect(dynamic host, int port,
+      dynamic sourceAddress, int sourcePort, Duration? timeout) {
+    return startConnect(host, port, sourceAddress, sourcePort)
         .then((ConnectionTask<_NativeSocket> task) {
       Future<_NativeSocket> socketFuture = task.socket;
       if (timeout != null) {
@@ -1653,8 +1661,8 @@
   @pragma("vm:external-name", "Socket_CreateUnixDomainConnect")
   external nativeCreateUnixDomainConnect(String addr, _Namespace namespace);
   @pragma("vm:external-name", "Socket_CreateBindConnect")
-  external nativeCreateBindConnect(
-      Uint8List addr, int port, Uint8List sourceAddr, int scope_id);
+  external nativeCreateBindConnect(Uint8List addr, int port,
+      Uint8List sourceAddr, int sourcePort, int scope_id);
   @pragma("vm:external-name", "Socket_CreateUnixDomainBindConnect")
   external nativeCreateUnixDomainBindConnect(
       String addr, String sourceAddr, _Namespace namespace);
@@ -1792,9 +1800,9 @@
   // Flag to handle Ctrl-D closing of stdio on Mac OS.
   bool _isMacOSTerminalInput = false;
 
-  static Future<RawSocket> connect(
-      dynamic host, int port, dynamic sourceAddress, Duration? timeout) {
-    return _NativeSocket.connect(host, port, sourceAddress, timeout)
+  static Future<RawSocket> connect(dynamic host, int port,
+      dynamic sourceAddress, int sourcePort, Duration? timeout) {
+    return _NativeSocket.connect(host, port, sourceAddress, sourcePort, timeout)
         .then((socket) {
       if (!const bool.fromEnvironment("dart.vm.product")) {
         _SocketProfile.collectNewSocket(
@@ -1805,8 +1813,8 @@
   }
 
   static Future<ConnectionTask<_RawSocket>> startConnect(
-      dynamic host, int port, dynamic sourceAddress) {
-    return _NativeSocket.startConnect(host, port, sourceAddress)
+      dynamic host, int port, dynamic sourceAddress, int sourcePort) {
+    return _NativeSocket.startConnect(host, port, sourceAddress, sourcePort)
         .then((ConnectionTask<_NativeSocket> nativeTask) {
       final Future<_RawSocket> raw =
           nativeTask.socket.then((_NativeSocket nativeSocket) {
@@ -2016,16 +2024,19 @@
 class Socket {
   @patch
   static Future<Socket> _connect(dynamic host, int port,
-      {dynamic sourceAddress, Duration? timeout}) {
+      {dynamic sourceAddress, int sourcePort = 0, Duration? timeout}) {
     return RawSocket.connect(host, port,
-            sourceAddress: sourceAddress, timeout: timeout)
+            sourceAddress: sourceAddress,
+            sourcePort: sourcePort,
+            timeout: timeout)
         .then((socket) => new _Socket(socket));
   }
 
   @patch
   static Future<ConnectionTask<Socket>> _startConnect(dynamic host, int port,
-      {dynamic sourceAddress}) {
-    return RawSocket.startConnect(host, port, sourceAddress: sourceAddress)
+      {dynamic sourceAddress, int sourcePort = 0}) {
+    return RawSocket.startConnect(host, port,
+            sourceAddress: sourceAddress, sourcePort: sourcePort)
         .then((rawTask) {
       Future<Socket> socket =
           rawTask.socket.then((rawSocket) => new _Socket(rawSocket));
diff --git a/sdk/lib/_internal/vm/lib/array.dart b/sdk/lib/_internal/vm/lib/array.dart
index c897b67..ba48fbe 100644
--- a/sdk/lib/_internal/vm/lib/array.dart
+++ b/sdk/lib/_internal/vm/lib/array.dart
@@ -61,8 +61,11 @@
   factory _List._ofGrowableList(_GrowableList<E> elements) {
     final int length = elements.length;
     final list = _List<E>(length);
-    for (int i = 0; i < length; i++) {
-      list[i] = elements[i];
+    // TODO(30102): Remove this loop zero-trip guard.
+    if (length > 0) {
+      for (int i = 0; i < length; i++) {
+        list[i] = elements[i];
+      }
     }
     return list;
   }
@@ -70,8 +73,11 @@
   factory _List._ofList(_List<E> elements) {
     final int length = elements.length;
     final list = _List<E>(length);
-    for (int i = 0; i < length; i++) {
-      list[i] = elements[i];
+    // TODO(30102): Remove this loop zero-trip guard.
+    if (length > 0) {
+      for (int i = 0; i < length; i++) {
+        list[i] = elements[i];
+      }
     }
     return list;
   }
@@ -79,8 +85,11 @@
   factory _List._ofImmutableList(_ImmutableList<E> elements) {
     final int length = elements.length;
     final list = _List<E>(length);
-    for (int i = 0; i < length; i++) {
-      list[i] = elements[i];
+    // TODO(30102): Remove this loop zero-trip guard.
+    if (length > 0) {
+      for (int i = 0; i < length; i++) {
+        list[i] = elements[i];
+      }
     }
     return list;
   }
diff --git a/sdk/lib/_internal/vm/lib/core_patch.dart b/sdk/lib/_internal/vm/lib/core_patch.dart
index 3118350..0d1d4a8 100644
--- a/sdk/lib/_internal/vm/lib/core_patch.dart
+++ b/sdk/lib/_internal/vm/lib/core_patch.dart
@@ -53,8 +53,6 @@
 
 import "dart:isolate" show Isolate;
 
-import "dart:math" show Random;
-
 import "dart:typed_data"
     show Endian, Uint8List, Int64List, Uint16List, Uint32List;
 
diff --git a/sdk/lib/_internal/vm/lib/date_patch.dart b/sdk/lib/_internal/vm/lib/date_patch.dart
index 249399a..d404a16 100644
--- a/sdk/lib/_internal/vm/lib/date_patch.dart
+++ b/sdk/lib/_internal/vm/lib/date_patch.dart
@@ -33,7 +33,7 @@
   static const _MONTH_INDEX = 7;
   static const _YEAR_INDEX = 8;
 
-  List? __parts;
+  List<int>? __parts;
 
   @patch
   DateTime.fromMillisecondsSinceEpoch(int millisecondsSinceEpoch,
@@ -191,7 +191,7 @@
     return list;
   }
 
-  get _parts {
+  List<int> get _parts {
     return __parts ??= _computeUpperPart(_localDateInUtcMicros);
   }
 
@@ -282,7 +282,7 @@
         _flooredDivision(year - 1601, 400);
   }
 
-  static bool _isLeapYear(y) {
+  static bool _isLeapYear(int y) {
     // (y % 16 == 0) matches multiples of 400, and is faster than % 400.
     return (y % 4 == 0) && ((y % 16 == 0) || (y % 100 != 0));
   }
diff --git a/sdk/lib/_internal/vm/lib/ffi_native_type_patch.dart b/sdk/lib/_internal/vm/lib/ffi_native_type_patch.dart
index 426a170..92e23c1 100644
--- a/sdk/lib/_internal/vm/lib/ffi_native_type_patch.dart
+++ b/sdk/lib/_internal/vm/lib/ffi_native_type_patch.dart
@@ -55,6 +55,7 @@
 @pragma("vm:entry-point")
 class Uint64 extends _NativeInteger {}
 
+// TODO(http://dartbug.com/47938): Implement as AbiSpecificInteger.
 @patch
 @pragma("vm:entry-point")
 class IntPtr extends _NativeInteger {}
diff --git a/sdk/lib/_internal/vm/lib/ffi_patch.dart b/sdk/lib/_internal/vm/lib/ffi_patch.dart
index 3af29c3..73d08b7 100644
--- a/sdk/lib/_internal/vm/lib/ffi_patch.dart
+++ b/sdk/lib/_internal/vm/lib/ffi_patch.dart
@@ -236,6 +236,15 @@
   factory Abi.current() => values[_abi()];
 }
 
+@pragma("vm:entry-point")
+class _FfiAbiSpecificMapping {
+  /// Indexed by [_abi].
+  @pragma("vm:entry-point")
+  final List<Object> nativeTypes;
+
+  const _FfiAbiSpecificMapping(this.nativeTypes);
+}
+
 /// Copies data byte-wise from [source] to [target].
 ///
 /// [source] and [target] should either be [Pointer] or [TypedData].
@@ -284,34 +293,42 @@
 // allocating a Pointer with in elementAt/offsetBy. Allocating these pointers
 // and GCing new spaces takes a lot of the benchmark time. The next speedup is
 // getting rid of these allocations by inlining these functions.
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_loadInt8")
 external int _loadInt8(Object typedDataBase, int offsetInBytes);
 
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_loadInt16")
 external int _loadInt16(Object typedDataBase, int offsetInBytes);
 
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_loadInt32")
 external int _loadInt32(Object typedDataBase, int offsetInBytes);
 
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_loadInt64")
 external int _loadInt64(Object typedDataBase, int offsetInBytes);
 
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_loadUint8")
 external int _loadUint8(Object typedDataBase, int offsetInBytes);
 
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_loadUint16")
 external int _loadUint16(Object typedDataBase, int offsetInBytes);
 
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_loadUint32")
 external int _loadUint32(Object typedDataBase, int offsetInBytes);
 
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_loadUint64")
 external int _loadUint64(Object typedDataBase, int offsetInBytes);
@@ -321,6 +338,14 @@
 external int _loadIntPtr(Object typedDataBase, int offsetInBytes);
 
 @pragma("vm:recognized", "other")
+external int _loadAbiSpecificInt<T extends AbiSpecificInteger>(
+    Object typedDataBase, int offsetInBytes);
+
+@pragma("vm:recognized", "other")
+external int _loadAbiSpecificIntAtIndex<T extends AbiSpecificInteger>(
+    Object typedDataBase, int index);
+
+@pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_loadFloat")
 external double _loadFloat(Object typedDataBase, int offsetInBytes);
 
@@ -341,34 +366,42 @@
 external Pointer<S> _loadPointer<S extends NativeType>(
     Object typedDataBase, int offsetInBytes);
 
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_storeInt8")
 external void _storeInt8(Object typedDataBase, int offsetInBytes, int value);
 
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_storeInt16")
 external void _storeInt16(Object typedDataBase, int offsetInBytes, int value);
 
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_storeInt32")
 external void _storeInt32(Object typedDataBase, int offsetInBytes, int value);
 
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_storeInt64")
 external void _storeInt64(Object typedDataBase, int offsetInBytes, int value);
 
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_storeUint8")
 external void _storeUint8(Object typedDataBase, int offsetInBytes, int value);
 
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_storeUint16")
 external void _storeUint16(Object typedDataBase, int offsetInBytes, int value);
 
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_storeUint32")
 external void _storeUint32(Object typedDataBase, int offsetInBytes, int value);
 
+@pragma("vm:entry-point")
 @pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_storeUint64")
 external void _storeUint64(Object typedDataBase, int offsetInBytes, int value);
@@ -378,6 +411,14 @@
 external void _storeIntPtr(Object typedDataBase, int offsetInBytes, int value);
 
 @pragma("vm:recognized", "other")
+external int _storeAbiSpecificInt<T extends AbiSpecificInteger>(
+    Object typedDataBase, int offsetInBytes, int value);
+
+@pragma("vm:recognized", "other")
+external int _storeAbiSpecificIntAtIndex<T extends AbiSpecificInteger>(
+    Object typedDataBase, int index, int value);
+
+@pragma("vm:recognized", "other")
 @pragma("vm:external-name", "Ffi_storeFloat")
 external void _storeFloat(
     Object typedDataBase, int offsetInBytes, double value);
@@ -937,6 +978,25 @@
       throw "UNREACHABLE: This case should have been rewritten in the CFE.";
 }
 
+extension AbiSpecificIntegerPointer<T extends AbiSpecificInteger>
+    on Pointer<T> {
+  @patch
+  int get value =>
+      throw "UNREACHABLE: This case should have been rewritten in the CFE.";
+
+  @patch
+  void set value(int value) =>
+      throw "UNREACHABLE: This case should have been rewritten in the CFE.";
+
+  @patch
+  int operator [](int index) =>
+      throw "UNREACHABLE: This case should have been rewritten in the CFE.";
+
+  @patch
+  void operator []=(int index, int value) =>
+      throw "UNREACHABLE: This case should have been rewritten in the CFE.";
+}
+
 extension PointerArray<T extends NativeType> on Array<Pointer<T>> {
   @patch
   Pointer<T> operator [](int index) =>
@@ -972,6 +1032,20 @@
   }
 }
 
+extension AbiSpecificIntegerArray on Array<AbiSpecificInteger> {
+  @patch
+  int operator [](int index) {
+    throw ArgumentError(
+        "Receiver should be a subtype of AbiSpecificInteger at compile-time.");
+  }
+
+  @patch
+  void operator []=(int index, int value) {
+    throw ArgumentError(
+        "Receiver should be a subtype of AbiSpecificInteger at compile-time.");
+  }
+}
+
 extension NativePort on SendPort {
   @patch
   @pragma("vm:external-name", "SendPortImpl_get_id")
diff --git a/sdk/lib/_internal/vm/lib/growable_array.dart b/sdk/lib/_internal/vm/lib/growable_array.dart
index 516996f..c6d9e46 100644
--- a/sdk/lib/_internal/vm/lib/growable_array.dart
+++ b/sdk/lib/_internal/vm/lib/growable_array.dart
@@ -110,7 +110,10 @@
   // Specialization of List.empty constructor for growable == true.
   // Used by pkg/vm/lib/transformations/list_factory_specializer.dart.
   @pragma("vm:prefer-inline")
-  factory _GrowableList.empty() => _GrowableList(0);
+  factory _GrowableList.empty() {
+    // Specialization of `return _GrowableList(0);`.
+    return _GrowableList<T>._withData(_emptyList);
+  }
 
   // Specialization of List.filled constructor for growable == true.
   // Used by pkg/vm/lib/transformations/list_factory_specializer.dart.
@@ -154,43 +157,61 @@
 
   factory _GrowableList._ofList(_List<T> elements) {
     final int length = elements.length;
-    final list = _GrowableList<T>(length);
-    for (int i = 0; i < length; i++) {
-      list[i] = elements[i];
+    if (length > 0) {
+      final data = _List(_adjustedCapacity(length));
+      for (int i = 0; i < length; i++) {
+        data[i] = elements[i];
+      }
+      final list = _GrowableList<T>._withData(data);
+      list._setLength(length);
+      return list;
     }
-    return list;
+    return _GrowableList<T>.empty();
   }
 
   factory _GrowableList._ofGrowableList(_GrowableList<T> elements) {
     final int length = elements.length;
-    final list = _GrowableList<T>(length);
-    for (int i = 0; i < length; i++) {
-      list[i] = elements[i];
+    if (length > 0) {
+      final data = _List(_adjustedCapacity(length));
+      for (int i = 0; i < length; i++) {
+        data[i] = elements[i];
+      }
+      final list = _GrowableList<T>._withData(data);
+      list._setLength(length);
+      return list;
     }
-    return list;
+    return _GrowableList<T>.empty();
   }
 
   factory _GrowableList._ofImmutableList(_ImmutableList<T> elements) {
     final int length = elements.length;
-    final list = _GrowableList<T>(length);
-    for (int i = 0; i < length; i++) {
-      list[i] = elements[i];
+    if (length > 0) {
+      final data = _List(_adjustedCapacity(length));
+      for (int i = 0; i < length; i++) {
+        data[i] = elements[i];
+      }
+      final list = _GrowableList<T>._withData(data);
+      list._setLength(length);
+      return list;
     }
-    return list;
+    return _GrowableList<T>.empty();
   }
 
   factory _GrowableList._ofEfficientLengthIterable(
       EfficientLengthIterable<T> elements) {
     final int length = elements.length;
-    final list = _GrowableList<T>(length);
     if (length > 0) {
+      final data = _List(_adjustedCapacity(length));
       int i = 0;
       for (var element in elements) {
-        list[i++] = element;
+        data[i++] = element;
       }
       if (i != length) throw ConcurrentModificationError(elements);
+      final list = _GrowableList<T>._withData(data);
+      list._setLength(length);
+      return list;
     }
-    return list;
+    return _GrowableList<T>.empty();
   }
 
   factory _GrowableList._ofOther(Iterable<T> elements) {
@@ -358,11 +379,13 @@
       // Use shared empty list as backing.
       return _emptyList;
     }
-    // Round up size to the next odd number, since this is free
-    // because of alignment requirements of the GC.
-    return new _List(capacity | 1);
+    return _List(_adjustedCapacity(capacity));
   }
 
+  // Round up size to the next odd number, since this is free
+  // because of alignment requirements of the GC.
+  static int _adjustedCapacity(int capacity) => capacity | 1;
+
   // Grow from 0 to 3, and then double + 1.
   int _nextCapacity(int old_capacity) => (old_capacity * 2) | 3;
 
@@ -501,14 +524,22 @@
   }
 
   List<T> toList({bool growable: true}) {
+    // TODO(sra): We should be able to replace the following with:
+    //
+    //     return growable
+    //         ? _GrowableList<T>._ofGrowableList(this)
+    //         : _List<T>._ofGrowableList(this);
+    //
+    // However, the extra call causes a 5% regression in `ListCopy.toList.2`.
+
     final length = this.length;
     if (growable) {
       if (length > 0) {
-        final list = new _List(length);
+        final data = new _List(_adjustedCapacity(length));
         for (int i = 0; i < length; i++) {
-          list[i] = this[i];
+          data[i] = this[i];
         }
-        final result = new _GrowableList<T>._withData(list);
+        final result = new _GrowableList<T>._withData(data);
         result._setLength(length);
         return result;
       }
diff --git a/sdk/lib/_internal/vm/lib/object_patch.dart b/sdk/lib/_internal/vm/lib/object_patch.dart
index 3a7b6bb..d0398a2 100644
--- a/sdk/lib/_internal/vm/lib/object_patch.dart
+++ b/sdk/lib/_internal/vm/lib/object_patch.dart
@@ -9,14 +9,6 @@
 @pragma("vm:external-name", "Object_getHash")
 external int _getHash(obj);
 
-/// Set hash code associated with the object if it is not set yet
-/// and return the current hash code. See [Object._objectHashCode]
-/// for why this function needs to check for already set hash code.
-@pragma("vm:recognized", "asm-intrinsic")
-@pragma("vm:exact-result-type", "dart:core#_Smi")
-@pragma("vm:external-name", "Object_setHashIfNotSetYet")
-external int _setHashIfNotSetYet(obj, int hash);
-
 @patch
 @pragma("vm:entry-point")
 class Object {
@@ -28,31 +20,9 @@
   @pragma("vm:external-name", "Object_equals")
   external bool operator ==(Object other);
 
-  // Helpers used to implement hashCode. If a hashCode is used, we remember it
-  // in a weak table in the VM (32 bit) or in the header of the object (64
-  // bit). A new hashCode value is calculated using a random number generator.
-  static final _hashCodeRnd = new Random();
-
-  static int _objectHashCode(obj) {
-    var result = _getHash(obj);
-    if (result == 0) {
-      // We want the hash to be a Smi value greater than 0.
-      do {
-        result = _hashCodeRnd.nextInt(0x40000000);
-      } while (result == 0);
-
-      // Caveat: we might be interrupted by vm-service which then
-      // can initialize [this] object's hash code, that is why we need to
-      // return the return value of [_setHashIfNotSetYet] rather than
-      // returning [result] itself.
-      return _setHashIfNotSetYet(obj, result);
-    }
-    return result;
-  }
-
   @patch
-  int get hashCode => _objectHashCode(this);
-  int get _identityHashCode => _objectHashCode(this);
+  int get hashCode => _getHash(this);
+  int get _identityHashCode => _getHash(this);
 
   @patch
   @pragma("vm:external-name", "Object_toString")
diff --git a/sdk/lib/async/broadcast_stream_controller.dart b/sdk/lib/async/broadcast_stream_controller.dart
index c2db270..bed1f7d 100644
--- a/sdk/lib/async/broadcast_stream_controller.dart
+++ b/sdk/lib/async/broadcast_stream_controller.dart
@@ -254,7 +254,6 @@
     } else {
       stackTrace ??= AsyncError.defaultStackTrace(error);
     }
-    if (stackTrace == null) throw "unreachable"; // TODO(40088)
     _sendError(error, stackTrace);
   }
 
diff --git a/sdk/lib/async/future.dart b/sdk/lib/async/future.dart
index 2283ba7..ea6c234 100644
--- a/sdk/lib/async/future.dart
+++ b/sdk/lib/async/future.dart
@@ -1097,7 +1097,6 @@
   } else {
     stackTrace ??= AsyncError.defaultStackTrace(error);
   }
-  if (stackTrace == null) throw "unreachable"; // TODO(40088).
   result._completeError(error, stackTrace);
 }
 
diff --git a/sdk/lib/async/future_impl.dart b/sdk/lib/async/future_impl.dart
index 52664b3..c3dc65b 100644
--- a/sdk/lib/async/future_impl.dart
+++ b/sdk/lib/async/future_impl.dart
@@ -29,7 +29,6 @@
     } else {
       stackTrace ??= AsyncError.defaultStackTrace(error);
     }
-    if (stackTrace == null) throw "unreachable"; // TODO(40088)
     _completeError(error, stackTrace);
   }
 
diff --git a/sdk/lib/async/stream_controller.dart b/sdk/lib/async/stream_controller.dart
index 7121af8..cacc72c 100644
--- a/sdk/lib/async/stream_controller.dart
+++ b/sdk/lib/async/stream_controller.dart
@@ -18,12 +18,54 @@
 ///
 /// This controller allows sending data, error and done events on
 /// its [stream].
+///
 /// This class can be used to create a simple stream that others
 /// can listen on, and to push events to that stream.
 ///
 /// It's possible to check whether the stream is paused or not, and whether
 /// it has subscribers or not, as well as getting a callback when either of
 /// these change.
+///
+/// Example:
+/// ```dart
+/// final streamController = StreamController(
+///   onPause: () => print('Paused'),
+///   onResume: () => print('Resumed'),
+///   onCancel: () => print('Cancelled'),
+///   onListen: () => print('Listens'),
+/// );
+///
+/// streamController.stream.listen(
+///   (event) => print('Event: $event'),
+///   onDone: () => print('Done'),
+///   onError: (error) => print(error),
+/// );
+/// ```
+/// To check whether there is a subscriber on the stream, use [hasListener].
+/// ```dart continued
+/// var hasListener = streamController.hasListener; // true
+/// ```
+/// To send data events to the stream, use [add] or [addStream].
+/// ```dart continued
+/// streamController.add(999);
+/// final stream = Stream<int>.periodic(
+///     const Duration(milliseconds: 200), (count) => count * count).take(4);
+/// await streamController.addStream(stream);
+/// ```
+/// To send an error event to the stream, use [addError] or [addStream].
+/// ```dart continued
+/// streamController.addError(Exception('Issue 101'));
+/// await streamController.addStream(Stream.error(Exception('Issue 404')));
+/// ```
+/// To check whether the stream is closed, use [isClosed].
+/// ```dart continued
+/// var isClosed = streamController.isClosed; // false
+/// ```
+/// To close the stream, use [close].
+/// ```dart continued
+/// await streamController.close();
+/// isClosed = streamController.isClosed; // true
+/// ```
 abstract class StreamController<T> implements StreamSink<T> {
   /// The stream that this controller is controlling.
   Stream<T> get stream;
@@ -286,7 +328,7 @@
 /// or microtask. This means that if it throws, the error will be reported as
 /// uncaught as soon as possible.
 /// This is one reason to add the event as the last thing in the original event
-/// handler - any action done after adding the event will delay the report of
+/// handler – any action done after adding the event will delay the report of
 /// errors in the event listener callbacks.
 ///
 /// If an event is added in a setting that isn't known to be another event,
@@ -565,7 +607,6 @@
     } else {
       stackTrace ??= AsyncError.defaultStackTrace(error);
     }
-    if (stackTrace == null) throw "unreachable"; // TODO(40088)
     _addError(error, stackTrace);
   }
 
diff --git a/sdk/lib/async/timer.dart b/sdk/lib/async/timer.dart
index 973a543..a77bdfa 100644
--- a/sdk/lib/async/timer.dart
+++ b/sdk/lib/async/timer.dart
@@ -4,7 +4,7 @@
 
 part of dart.async;
 
-/// A count-down timer that can be configured to fire once or repeatedly.
+/// A countdown timer that can be configured to fire once or repeatedly.
 ///
 /// The timer counts down from the specified duration to 0.
 /// When the timer reaches 0, the timer invokes the specified callback function.
@@ -17,27 +17,33 @@
 /// following example (taking advantage of the multiplication operator of
 /// the [Duration] class):
 /// ```dart
-/// const timeout = Duration(seconds: 3);
-/// const ms = Duration(milliseconds: 1);
-///
-/// Timer startTimeout([int? milliseconds]) {
-///   var duration = milliseconds == null ? timeout : ms * milliseconds;
-///   return Timer(duration, handleTimeout);
+/// void main() {
+///   scheduleTimeout(5 * 1000); // 5 seconds.
 /// }
-/// ...
+///
+/// Timer scheduleTimeout([int milliseconds = 10000]) =>
+///     Timer(Duration(milliseconds: milliseconds), handleTimeout);
+///
 /// void handleTimeout() {  // callback function
-///   ...
+///   // Do some work.
 /// }
 /// ```
-/// Note: If Dart code using [Timer] is compiled to JavaScript, the finest
+/// **Note:** If Dart code using [Timer] is compiled to JavaScript, the finest
 /// granularity available in the browser is 4 milliseconds.
 ///
-/// See [Stopwatch] for measuring elapsed time.
+/// See also:
+/// * [Stopwatch] for measuring elapsed time.
 abstract class Timer {
   /// Creates a new timer.
   ///
   /// The [callback] function is invoked after the given [duration].
   ///
+  /// Example:
+  /// ```dart
+  /// final timer =
+  ///     Timer(const Duration(seconds: 5), () => print('Timer finished'));
+  /// // Outputs after 5 seconds: "Timer finished".
+  /// ```
   factory Timer(Duration duration, void Function() callback) {
     if (Zone.current == Zone.root) {
       // No need to bind the callback. We know that the root's timer will
@@ -64,6 +70,24 @@
   /// scheduled for - even if the actual callback was delayed.
   ///
   /// [duration] must a non-negative [Duration].
+  ///
+  /// Example:
+  /// ```dart
+  /// var counter = 3;
+  /// Timer.periodic(const Duration(seconds: 2), (timer) {
+  ///   print(timer.tick);
+  ///   counter--;
+  ///   if (counter == 0) {
+  ///     print('Cancel timer');
+  ///     timer.cancel();
+  ///   }
+  /// });
+  /// // Outputs:
+  /// // 1
+  /// // 2
+  /// // 3
+  /// // "Cancel timer"
+  /// ```
   factory Timer.periodic(Duration duration, void callback(Timer timer)) {
     if (Zone.current == Zone.root) {
       // No need to bind the callback. We know that the root's timer will
@@ -77,6 +101,11 @@
   /// Runs the given [callback] asynchronously as soon as possible.
   ///
   /// This function is equivalent to `new Timer(Duration.zero, callback)`.
+  ///
+  /// Example:
+  /// ```dart
+  /// Timer.run(() => print('timer run'));
+  /// ```
   static void run(void Function() callback) {
     new Timer(Duration.zero, callback);
   }
@@ -86,6 +115,14 @@
   /// Once a [Timer] has been canceled, the callback function will not be called
   /// by the timer. Calling [cancel] more than once on a [Timer] is allowed, and
   /// will have no further effect.
+  ///
+  /// Example:
+  /// ```dart
+  /// final timer =
+  ///     Timer(const Duration(seconds: 5), () => print('Timer finished'));
+  /// // Cancel timer, callback never called.
+  /// timer.cancel();
+  /// ```
   void cancel();
 
   /// The number of durations preceding the most recent timer event.
@@ -99,6 +136,25 @@
   /// and no callback is invoked for them.
   /// The [tick] count reflects the number of durations that have passed and
   /// not the number of callback invocations that have happened.
+  ///
+  /// Example:
+  /// ```dart
+  /// final stopwatch = Stopwatch()..start();
+  /// Timer.periodic(const Duration(seconds: 1), (timer) {
+  ///   print(timer.tick);
+  ///   if (timer.tick == 1) {
+  ///     while (stopwatch.elapsedMilliseconds < 4500) {
+  ///       // Run uninterrupted for another 3.5 seconds!
+  ///       // The latest due tick after that is the 4-second tick.
+  ///     }
+  ///   } else {
+  ///     timer.cancel();
+  ///   }
+  /// });
+  /// // Outputs:
+  /// // 1
+  /// // 4
+  /// ```
   int get tick;
 
   /// Returns whether the timer is still active.
diff --git a/sdk/lib/collection/collections.dart b/sdk/lib/collection/collections.dart
index 9b43996..1137f52 100644
--- a/sdk/lib/collection/collections.dart
+++ b/sdk/lib/collection/collections.dart
@@ -8,6 +8,17 @@
 ///
 /// The source of the elements may be a [List] or any [Iterable] with
 /// efficient [Iterable.length] and [Iterable.elementAt].
+///
+/// ```dart
+/// final numbers = <int>[10, 20, 30];
+/// final unmodifiableListView = UnmodifiableListView(numbers);
+///
+/// // Insert new elements into the original list.
+/// numbers.addAll([40, 50]);
+/// print(unmodifiableListView); // [10, 20, 30, 40, 50]
+///
+/// unmodifiableListView.remove(20); // Throws.
+/// ```
 class UnmodifiableListView<E> extends UnmodifiableListBase<E> {
   final Iterable<E> _source;
 
diff --git a/sdk/lib/collection/maps.dart b/sdk/lib/collection/maps.dart
index b0ab270..b8673b1 100644
--- a/sdk/lib/collection/maps.dart
+++ b/sdk/lib/collection/maps.dart
@@ -200,7 +200,7 @@
 /// Basic implementation of an unmodifiable [Map].
 ///
 /// This class has a basic implementation of all but two of the members of
-/// an umodifiable [Map].
+/// an unmodifiable [Map].
 /// A simple unmodifiable `Map` class can be implemented by extending this
 /// class and implementing `keys` and `operator[]`.
 ///
@@ -376,6 +376,17 @@
 /// A wrapper around a `Map` that forwards all members to the map provided in
 /// the constructor, except for operations that modify the map.
 /// Modifying operations throw instead.
+///
+/// ```dart
+/// final baseMap = <int, String>{1: 'Mars', 2: 'Mercury', 3: 'Venus'};
+/// final unmodifiableMapView = UnmodifiableMapView(baseMap);
+///
+/// // Remove an entry from the original map.
+/// baseMap.remove(3);
+/// print(unmodifiableMapView); // {1: Mars, 2: Mercury}
+///
+/// unmodifiableMapView.remove(1); // Throws.
+/// ```
 class UnmodifiableMapView<K, V> extends MapView<K, V>
     with _UnmodifiableMapMixin<K, V> {
   UnmodifiableMapView(Map<K, V> map) : super(map);
diff --git a/sdk/lib/collection/set.dart b/sdk/lib/collection/set.dart
index 81ca0a8..f59b56d 100644
--- a/sdk/lib/collection/set.dart
+++ b/sdk/lib/collection/set.dart
@@ -400,6 +400,17 @@
 ///
 /// Methods that could change the set, such as [add] and [remove],
 /// must not be called.
+///
+/// ```dart
+/// final baseSet = <String>{'Mars', 'Mercury', 'Earth', 'Venus'};
+/// final unmodifiableSetView = UnmodifiableSetView(baseSet);
+///
+/// // Remove an element from the original set.
+/// baseSet.remove('Venus');
+/// print(unmodifiableSetView); // {Mars, Mercury, Earth}
+///
+/// unmodifiableSetView.remove('Earth'); // Throws.
+/// ```
 @Since("2.12")
 class UnmodifiableSetView<E> extends SetBase<E> with _UnmodifiableSetMixin<E> {
   final Set<E> _source;
diff --git a/sdk/lib/core/date_time.dart b/sdk/lib/core/date_time.dart
index 2281fd8..0bd6884 100644
--- a/sdk/lib/core/date_time.dart
+++ b/sdk/lib/core/date_time.dart
@@ -9,94 +9,111 @@
 /// DateTimes can represent time values that are at a distance of at most
 /// 100,000,000 days from epoch (1970-01-01 UTC): -271821-04-20 to 275760-09-13.
 ///
-/// Create a DateTime object by using one of the constructors
+/// Create a `DateTime` object by using one of the constructors
 /// or by parsing a correctly formatted string,
 /// which complies with a subset of ISO 8601.
-/// Note that hours are specified between 0 and 23,
+/// **Note:** hours are specified between 0 and 23,
 /// as in a 24-hour clock.
-/// For example:
 ///
+/// For example:
 /// ```dart
-/// var now = DateTime.now();
-/// var berlinWallFell = DateTime.utc(1989, 11, 9);
-/// var moonLanding = DateTime.parse("1969-07-20 20:18:04Z");  // 8:18pm
+/// final now = DateTime.now();
+/// final berlinWallFell = DateTime.utc(1989, 11, 9);
+/// final moonLanding = DateTime.parse('1969-07-20 20:18:04Z'); // 8:18pm
 /// ```
 ///
-/// A DateTime object is anchored either in the UTC time zone
+/// A `DateTime` object is anchored either in the UTC time zone
 /// or in the local time zone of the current computer
 /// when the object is created.
 ///
 /// Once created, neither the value nor the time zone
-/// of a DateTime object may be changed.
+/// of a `DateTime` object may be changed.
 ///
 /// You can use properties to get
-/// the individual units of a DateTime object.
-///
-/// ```dart
-/// assert(berlinWallFell.month == 11);
-/// assert(moonLanding.hour == 20);
+/// the individual units of a `DateTime` object.
 /// ```
-///
+/// print(berlinWallFell.year); // 1989
+/// print(berlinWallFell.month); // 11
+/// print(berlinWallFell.day); // 9
+/// print(moonLanding.hour); // 20
+/// print(moonLanding.minute); // 18
+/// ```
 /// For convenience and readability,
-/// the DateTime class provides a constant for each day and month
+/// the `DateTime` class provides a constant for each `day` and `month`
 /// name - for example, [august] and [friday].
 /// You can use these constants to improve code readability:
-///
 /// ```dart
-/// var berlinWallFell = DateTime.utc(1989, DateTime.november, 9);
+/// final berlinWallFell = DateTime.utc(1989, DateTime.november, 9);
+/// print(DateTime.november); // 11
+/// assert(berlinWallFell.month == DateTime.november);
 /// assert(berlinWallFell.weekday == DateTime.thursday);
 /// ```
 ///
-/// Day and month values begin at 1, and the week starts on Monday.
+/// `Day` and `month` values begin at 1, and the week starts on `Monday`.
 /// That is, the constants [january] and [monday] are both 1.
 ///
 /// ## Working with UTC and local time
 ///
-/// A DateTime object is in the local time zone
+/// A `DateTime` object is in the local time zone
 /// unless explicitly created in the UTC time zone.
+/// Use [isUtc] to determine whether a `DateTime` object is based in UTC.
 ///
 /// ```dart
-/// var dDay = DateTime.utc(1944, 6, 6);
-/// ```
+/// final dDay = DateTime.utc(1944, 6, 6);
+/// print(dDay.isUtc); // true
 ///
-/// Use [isUtc] to determine whether a DateTime object is based in UTC.
+/// final dDayLocal = DateTime(1944, 6, 6);
+/// print(dDayLocal.isUtc); // false
+/// ```
 /// Use the methods [toLocal] and [toUtc]
 /// to get the equivalent date/time value specified in the other time zone.
+/// ```
+/// final localDay = dDay.toLocal(); // e.g. 1944-06-06 02:00:00.000
+/// print(localDay.isUtc); // false
+///
+/// final utcFromLocal = localDay.toUtc(); // 1944-06-06 00:00:00.000Z
+/// print(utcFromLocal.isUtc); // true
+/// ```
 /// Use [timeZoneName] to get an abbreviated name of the time zone
-/// for the DateTime object.
+/// for the `DateTime` object.
+/// ```
+/// print(dDay.timeZoneName); // UTC
+/// print(localDay.timeZoneName); // e.g. EET
+/// ```
 /// To find the difference
-/// between UTC and the time zone of a DateTime object
+/// between UTC and the time zone of a `DateTime` object
 /// call [timeZoneOffset].
+/// ```
+/// print(dDay.timeZoneOffset); // 0:00:00.000000
+/// print(localDay.timeZoneOffset); // e.g. 2:00:00.000000
+/// ```
 ///
 /// ## Comparing DateTime objects
 ///
-/// The DateTime class contains several handy methods,
-/// such as [isAfter], [isBefore], and [isAtSameMomentAs],
-/// for comparing DateTime objects.
-///
-/// ```dart
-/// assert(berlinWallFell.isAfter(moonLanding) == true);
-/// assert(berlinWallFell.isBefore(moonLanding) == false);
+/// The `DateTime` class contains methods for comparing `DateTime`s
+/// chronologically, such as [isAfter], [isBefore], and [isAtSameMomentAs].
+/// ```
+/// print(berlinWallFell.isAfter(moonLanding)); // true
+/// print(berlinWallFell.isBefore(moonLanding)); // false
+/// print(dDay.isAtSameMomentAs(localDay)); // true
 /// ```
 ///
 /// ## Using DateTime with Duration
 ///
 /// Use the [add] and [subtract] methods with a [Duration] object
-/// to create a DateTime object based on another.
-/// For example, to find the date that is sixty days (24 * 60 hours) after today,
-/// write:
-///
+/// to create a `DateTime` object based on another.
+/// For example, to find the point in time that is 36 hours after now,
+/// you can write:
 /// ```dart
-/// var now = DateTime.now();
-/// var sixtyDaysFromNow = now.add(const Duration(days: 60));
+/// final now = DateTime.now();
+/// final later = now.add(const Duration(hours: 36));
 /// ```
 ///
-/// To find out how much time is between two DateTime objects use
+/// To find out how much time is between two `DateTime` objects use
 /// [difference], which returns a [Duration] object:
-///
-/// ```dart
-/// var difference = berlinWallFell.difference(moonLanding);
-/// assert(difference.inDays == 7416);
+/// ```
+/// final difference = berlinWallFell.difference(moonLanding);
+/// print(difference.inDays); // 7416
 /// ```
 ///
 /// The difference between two dates in different time zones
@@ -111,13 +128,11 @@
 ///
 /// ## Other resources
 ///
-/// See [Duration] to represent a span of time.
-/// See [Stopwatch] to measure timespans.
-///
-/// The DateTime class does not provide internationalization.
-/// To internationalize your code, use
-/// the [intl](https://pub.dev/packages/intl) package.
-///
+///  * See [Duration] to represent a span of time.
+///  * See [Stopwatch] to measure timespans.
+///  * The `DateTime` class does not provide internationalization.
+///  To internationalize your code, use
+///  the [intl](https://pub.dev/packages/intl) package.
 class DateTime implements Comparable<DateTime> {
   // Weekday constants that are returned by [weekday] method:
   static const int monday = 1;
@@ -154,20 +169,22 @@
   /// True if this [DateTime] is set to UTC time.
   ///
   /// ```dart
-  /// var dDay = DateTime.utc(1944, 6, 6);
-  /// assert(dDay.isUtc);
-  /// ```
+  /// final dDay = DateTime.utc(1944, 6, 6);
+  /// print(dDay.isUtc); // true
   ///
+  /// final local = DateTime(1944, 6, 6);
+  /// print(local.isUtc); // false
+  /// ```
   final bool isUtc;
 
   /// Constructs a [DateTime] instance specified in the local time zone.
   ///
   /// For example,
-  /// to create a DateTime object representing the 7th of September 2017,
+  /// to create a `DateTime` object representing the 7th of September 2017,
   /// 5:30pm
   ///
   /// ```dart
-  /// var dentistAppointment = DateTime(2017, 9, 7, 17, 30);
+  /// final dentistAppointment = DateTime(2017, 9, 7, 17, 30);
   /// ```
   DateTime(int year,
       [int month = 1,
@@ -183,10 +200,10 @@
   /// Constructs a [DateTime] instance specified in the UTC time zone.
   ///
   /// ```dart
-  /// var moonLanding = DateTime.utc(1969, 7, 20, 20, 18, 04);
+  /// final moonLanding = DateTime.utc(1969, 7, 20, 20, 18, 04);
   /// ```
   ///
-  /// When dealing with dates or historic events prefer to use UTC DateTimes,
+  /// When dealing with dates or historic events, preferably use UTC DateTimes,
   /// since they are unaffected by daylight-saving changes and are unaffected
   /// by the local timezone.
   DateTime.utc(int year,
@@ -204,7 +221,7 @@
   /// local time zone.
   ///
   /// ```dart
-  /// var thisInstant = DateTime.now();
+  /// final now = DateTime.now();
   /// ```
   DateTime.now() : this._now();
 
@@ -212,7 +229,7 @@
   ///
   /// Throws a [FormatException] if the input string cannot be parsed.
   ///
-  /// The function parses a subset of ISO 8601
+  /// The function parses a subset of ISO 8601,
   /// which includes the subset accepted by RFC 3339.
   ///
   /// The accepted inputs are currently:
@@ -233,7 +250,7 @@
   ///   possibly separated from the previous by a space.
   ///   The time zone is either 'z' or 'Z', or it is a signed two digit hour
   ///   part and an optional two digit minute part. The sign must be either
-  ///   "+" or "-", and can not be omitted.
+  ///   "+" or "-", and cannot be omitted.
   ///   The minutes may be separated from the hours by a ':'.
   ///   Examples: "Z", "-10", "+01:30", "+1130".
   ///
@@ -354,23 +371,33 @@
   /// The constructed [DateTime] represents
   /// 1970-01-01T00:00:00Z + [millisecondsSinceEpoch] ms in the given
   /// time zone (local or UTC).
+  /// ```dart
+  /// final newYearsDay =
+  ///     DateTime.fromMillisecondsSinceEpoch(1640979000000, isUtc:true);
+  /// print(newYearsDay); // 2022-01-01 10:00:00.000Z
+  /// ```
   external DateTime.fromMillisecondsSinceEpoch(int millisecondsSinceEpoch,
       {bool isUtc = false});
 
   /// Constructs a new [DateTime] instance
   /// with the given [microsecondsSinceEpoch].
   ///
-  /// If [isUtc] is false then the date is in the local time zone.
+  /// If [isUtc] is false, then the date is in the local time zone.
   ///
   /// The constructed [DateTime] represents
   /// 1970-01-01T00:00:00Z + [microsecondsSinceEpoch] us in the given
   /// time zone (local or UTC).
+  /// ```dart
+  /// final newYearsEve =
+  ///     DateTime.fromMicrosecondsSinceEpoch(1640901600000000, isUtc:true);
+  /// print(newYearsEve); // 2021-12-31 19:30:00.000Z
+  /// ```
   external DateTime.fromMicrosecondsSinceEpoch(int microsecondsSinceEpoch,
       {bool isUtc = false});
 
   /// Constructs a new [DateTime] instance with the given value.
   ///
-  /// If [isUtc] is false then the date is in the local time zone.
+  /// If [isUtc] is false, then the date is in the local time zone.
   DateTime._withValue(this._value, {required this.isUtc}) {
     if (millisecondsSinceEpoch.abs() > _maxMillisecondsSinceEpoch ||
         (millisecondsSinceEpoch.abs() == _maxMillisecondsSinceEpoch &&
@@ -386,11 +413,12 @@
   /// same time zone (UTC or local).
   ///
   /// ```dart
-  /// var dDayUtc = DateTime.utc(1944, 6, 6);
-  /// var dDayLocal = dDayUtc.toLocal();
+  /// final dDayUtc = DateTime.utc(1944, 6, 6);
+  /// final dDayLocal = dDayUtc.toLocal();
   ///
   /// // These two dates are at the same moment, but are in different zones.
   /// assert(dDayUtc != dDayLocal);
+  /// print(dDayUtc != dDayLocal); // true
   /// ```
   ///
   /// See [isAtSameMomentAs] for a comparison that compares moments in time
@@ -403,17 +431,17 @@
   /// of whether the time is in UTC or in the local time zone.
   ///
   /// ```dart
-  /// var now = DateTime.now();
-  /// var earlier = now.subtract(const Duration(seconds: 5));
-  /// assert(earlier.isBefore(now));
-  /// assert(!now.isBefore(now));
+  /// final now = DateTime.now();
+  /// final earlier = now.subtract(const Duration(seconds: 5));
+  /// print(earlier.isBefore(now)); // true
+  /// print(!now.isBefore(now)); // true
   ///
   /// // This relation stays the same, even when changing timezones.
-  /// assert(earlier.isBefore(now.toUtc()));
-  /// assert(earlier.toUtc().isBefore(now));
+  /// print(earlier.isBefore(now.toUtc())); // true
+  /// print(earlier.toUtc().isBefore(now)); // true
   ///
-  /// assert(!now.toUtc().isBefore(now));
-  /// assert(!now.isBefore(now.toUtc()));
+  /// print(!now.toUtc().isBefore(now)); // true
+  /// print(!now.isBefore(now.toUtc())); // true
   /// ```
   external bool isBefore(DateTime other);
 
@@ -423,17 +451,17 @@
   /// of whether the time is in UTC or in the local time zone.
   ///
   /// ```dart
-  /// var now = DateTime.now();
-  /// var later = now.add(const Duration(seconds: 5));
-  /// assert(later.isAfter(now));
-  /// assert(!now.isBefore(now));
+  /// final now = DateTime.now();
+  /// final later = now.add(const Duration(seconds: 5));
+  /// print(later.isAfter(now)); // true
+  /// print(!now.isBefore(now)); // true
   ///
   /// // This relation stays the same, even when changing timezones.
-  /// assert(later.isAfter(now.toUtc()));
-  /// assert(later.toUtc().isAfter(now));
+  /// print(later.isAfter(now.toUtc())); // true
+  /// print(later.toUtc().isAfter(now)); // true
   ///
-  /// assert(!now.toUtc().isAfter(now));
-  /// assert(!now.isAfter(now.toUtc()));
+  /// print(!now.toUtc().isAfter(now)); // true
+  /// print(!now.isAfter(now.toUtc())); // true
   /// ```
   external bool isAfter(DateTime other);
 
@@ -443,26 +471,38 @@
   /// time zone.
   ///
   /// ```dart
-  /// var now = DateTime.now();
-  /// var later = now.add(const Duration(seconds: 5));
-  /// assert(!later.isAtSameMomentAs(now));
-  /// assert(now.isAtSameMomentAs(now));
+  /// final now = DateTime.now();
+  /// final later = now.add(const Duration(seconds: 5));
+  /// print(!later.isAtSameMomentAs(now)); // true
+  /// print(now.isAtSameMomentAs(now)); // true
   ///
   /// // This relation stays the same, even when changing timezones.
-  /// assert(!later.isAtSameMomentAs(now.toUtc()));
-  /// assert(!later.toUtc().isAtSameMomentAs(now));
+  /// print(!later.isAtSameMomentAs(now.toUtc())); // true
+  /// print(!later.toUtc().isAtSameMomentAs(now)); // true
   ///
-  /// assert(now.toUtc().isAtSameMomentAs(now));
-  /// assert(now.isAtSameMomentAs(now.toUtc()));
+  /// print(now.toUtc().isAtSameMomentAs(now)); // true
+  /// print(now.isAtSameMomentAs(now.toUtc())); // true
   /// ```
   external bool isAtSameMomentAs(DateTime other);
 
   /// Compares this DateTime object to [other],
   /// returning zero if the values are equal.
   ///
-  /// Returns a negative value if this DateTime [isBefore] [other]. It returns 0
-  /// if it [isAtSameMomentAs] [other], and returns a positive value otherwise
-  /// (when this [isAfter] [other]).
+  /// A [compareTo] function returns:
+  ///  * a negative value if this DateTime [isBefore] [other].
+  ///  * `0` if this DateTime [isAtSameMomentAs] [other], and
+  ///  * a positive value otherwise (when this DateTime [isAfter] [other]).
+  ///
+  /// ```dart
+  /// final now = DateTime.now();
+  /// final future = now.add(const Duration(days: 2));
+  /// final past = now.subtract(const Duration(days: 2));
+  /// final newDate = now.toUtc();
+  ///
+  /// print(now.compareTo(future)); // -1
+  /// print(now.compareTo(past)); // 1
+  /// print(now.compareTo(newDate)); // 0
+  /// ```
   external int compareTo(DateTime other);
 
   int get hashCode => (_value ^ (_value >> 30)) & 0x3FFFFFFF;
@@ -569,6 +609,11 @@
   ///   0, then this part is omitted.
   ///
   /// The resulting string can be parsed back using [parse].
+  /// ```dart
+  /// final moonLanding = DateTime.utc(1969, 7, 20, 20, 18, 04);
+  /// final isoDate = moonLanding.toIso8601String();
+  /// print(isoDate); // 1969-07-20T20:18:04.000Z
+  /// ```
   String toIso8601String() {
     String y =
         (year >= -9999 && year <= 9999) ? _fourDigits(year) : _sixDigits(year);
@@ -589,8 +634,8 @@
   /// Returns a new [DateTime] instance with [duration] added to [this].
   ///
   /// ```dart
-  /// var today = DateTime.now();
-  /// var fiftyDaysFromNow = today.add(const Duration(days: 50));
+  /// final today = DateTime.now();
+  /// final fiftyDaysFromNow = today.add(const Duration(days: 50));
   /// ```
   ///
   /// Notice that the duration being added is actually 50 * 24 * 60 * 60
@@ -604,8 +649,8 @@
   /// Returns a new [DateTime] instance with [duration] subtracted from [this].
   ///
   /// ```dart
-  /// DateTime today = DateTime.now();
-  /// DateTime fiftyDaysAgo = today.subtract(const Duration(days: 50));
+  /// final today = DateTime.now();
+  /// final fiftyDaysAgo = today.subtract(const Duration(days: 50));
   /// ```
   ///
   /// Notice that the duration being subtracted is actually 50 * 24 * 60 * 60
@@ -622,11 +667,11 @@
   /// The returned [Duration] will be negative if [other] occurs after [this].
   ///
   /// ```dart
-  /// var berlinWallFell = DateTime.utc(1989, DateTime.november, 9);
-  /// var dDay = DateTime.utc(1944, DateTime.june, 6);
+  /// final berlinWallFell = DateTime.utc(1989, DateTime.november, 9);
+  /// final dDay = DateTime.utc(1944, DateTime.june, 6);
   ///
-  /// Duration difference = berlinWallFell.difference(dDay);
-  /// assert(difference.inDays == 16592);
+  /// final difference = berlinWallFell.difference(dDay);
+  /// print(difference.inDays); // 16592
   /// ```
   ///
   /// The difference is measured in seconds and fractions of seconds.
@@ -639,9 +684,10 @@
   /// For example, in Australia, similar code using local time instead of UTC:
   ///
   /// ```dart
-  /// var berlinWallFell = DateTime(1989, DateTime.november, 9);
-  /// var dDay = DateTime(1944, DateTime.june, 6);
-  /// Duration difference = berlinWallFell.difference(dDay);
+  /// final berlinWallFell = DateTime(1989, DateTime.november, 9);
+  /// final dDay = DateTime(1944, DateTime.june, 6);
+  /// final difference = berlinWallFell.difference(dDay);
+  /// print(difference.inDays); // 16591
   /// assert(difference.inDays == 16592);
   /// ```
   /// will fail because the difference is actually 16591 days and 23 hours, and
@@ -707,21 +753,39 @@
   /// Note, that JavaScript, Python and C return the difference between UTC and
   /// local time. Java, C# and Ruby return the difference between local time and
   /// UTC.
+  ///
+  /// For example, using local time in San Francisco, United States:
+  /// ```dart
+  /// final dateUS = DateTime.parse('2021-11-01 20:18:04Z').toLocal();
+  /// print(dateUS); // 2021-11-01 13:18:04.000
+  /// print(dateUS.timeZoneName); // PDT ( Pacific Daylight Time )
+  /// print(dateUS.timeZoneOffset.inHours); // -7
+  /// print(dateUS.timeZoneOffset.inMinutes); // -420
+  /// ```
+  ///
+  /// For example, using local time in Canberra, Australia:
+  /// ```dart
+  /// final dateAus = DateTime.parse('2021-11-01 20:18:04Z').toLocal();
+  /// print(dateAus); // 2021-11-02 07:18:04.000
+  /// print(dateAus.timeZoneName); // AEDT ( Australian Eastern Daylight Time )
+  /// print(dateAus.timeZoneOffset.inHours); // 11
+  /// print(dateAus.timeZoneOffset.inMinutes); // 660
+  /// ```
   external Duration get timeZoneOffset;
 
   /// The year.
   ///
   /// ```dart
-  /// var moonLanding = DateTime.parse("1969-07-20 20:18:04Z");
-  /// assert(moonLanding.year == 1969);
+  /// final moonLanding = DateTime.parse('1969-07-20 20:18:04Z');
+  /// print(moonLanding.year); // 1969
   /// ```
   external int get year;
 
   /// The month `[1..12]`.
   ///
   /// ```dart
-  /// var moonLanding = DateTime.parse("1969-07-20 20:18:04Z");
-  /// assert(moonLanding.month == 7);
+  /// final moonLanding = DateTime.parse('1969-07-20 20:18:04Z');
+  /// print(moonLanding.month); // 7
   /// assert(moonLanding.month == DateTime.july);
   /// ```
   external int get month;
@@ -729,48 +793,48 @@
   /// The day of the month `[1..31]`.
   ///
   /// ```dart
-  /// var moonLanding = DateTime.parse("1969-07-20 20:18:04Z");
-  /// assert(moonLanding.day == 20);
+  /// final moonLanding = DateTime.parse('1969-07-20 20:18:04Z');
+  /// print(moonLanding.day); // 20
   /// ```
   external int get day;
 
   /// The hour of the day, expressed as in a 24-hour clock `[0..23]`.
   ///
   /// ```dart
-  /// var moonLanding = DateTime.parse("1969-07-20 20:18:04Z");
-  /// assert(moonLanding.hour == 20);
+  /// final moonLanding = DateTime.parse('1969-07-20 20:18:04Z');
+  /// print(moonLanding.hour); // 20
   /// ```
   external int get hour;
 
   /// The minute `[0...59]`.
   ///
   /// ```dart
-  /// var moonLanding = DateTime.parse("1969-07-20 20:18:04Z");
-  /// assert(moonLanding.minute == 18);
+  /// final moonLanding = DateTime.parse('1969-07-20 20:18:04Z');
+  /// print(moonLanding.minute); // 18
   /// ```
   external int get minute;
 
   /// The second `[0...59]`.
   ///
   /// ```dart
-  /// var moonLanding = DateTime.parse("1969-07-20 20:18:04Z");
-  /// assert(moonLanding.second == 4);
+  /// final moonLanding = DateTime.parse('1969-07-20 20:18:04Z');
+  /// print(moonLanding.second); // 4
   /// ```
   external int get second;
 
   /// The millisecond `[0...999]`.
   ///
   /// ```dart
-  /// var moonLanding = DateTime.parse("1969-07-20 20:18:04Z");
-  /// assert(moonLanding.millisecond == 0);
+  /// final date = DateTime.parse('1970-01-01 05:01:01.234567Z');
+  /// print(date.millisecond); // 234
   /// ```
   external int get millisecond;
 
   /// The microsecond `[0...999]`.
   ///
   /// ```dart
-  /// var moonLanding = DateTime.parse("1969-07-20 20:18:04Z");
-  /// assert(moonLanding.microsecond == 0);
+  /// final date = DateTime.parse('1970-01-01 05:01:01.234567Z');
+  /// print(date.microsecond); // 567
   /// ```
   external int get microsecond;
 
@@ -780,8 +844,8 @@
   /// a week starts with Monday, which has the value 1.
   ///
   /// ```dart
-  /// var moonLanding = DateTime.parse("1969-07-20 20:18:04Z");
-  /// assert(moonLanding.weekday == 7);
+  /// final moonLanding = DateTime.parse('1969-07-20 20:18:04Z');
+  /// print(moonLanding.weekday); // 7
   /// assert(moonLanding.weekday == DateTime.sunday);
   /// ```
   external int get weekday;
diff --git a/sdk/lib/core/double.dart b/sdk/lib/core/double.dart
index 2bf8104..7c04f358 100644
--- a/sdk/lib/core/double.dart
+++ b/sdk/lib/core/double.dart
@@ -16,6 +16,11 @@
 ///
 /// It is a compile-time error for a class to attempt to extend or implement
 /// double.
+///
+/// **See also:**
+/// * [num] the super class for [double].
+/// * [Numbers](https://dart.dev/guides/language/numbers) in
+/// [A tour of the Dart language](https://dart.dev/guides/language/language-tour).
 abstract class double extends num {
   static const double nan = 0.0 / 0.0;
   static const double infinity = 1.0 / 0.0;
@@ -54,7 +59,14 @@
   ///  `(3.5).round() == 4` and `(-3.5).round() == -4`.
   ///
   /// Throws an [UnsupportedError] if this number is not finite
-  /// (NaN or an infinity), .
+  /// (NaN or an infinity).
+  /// ```dart
+  /// print(3.0.round()); // 3
+  /// print(3.25.round()); // 3
+  /// print(3.5.round()); // 4
+  /// print(3.75.round()); // 4
+  /// print((-3.5).round()); // -4
+  /// ```
   int round();
 
   /// Returns the greatest integer no greater than this number.
@@ -62,15 +74,31 @@
   /// Rounds the number towards negative infinity.
   ///
   /// Throws an [UnsupportedError] if this number is not finite
-  /// (NaN or infinity), .
+  /// (NaN or infinity).
+  /// ```dart
+  /// print(1.99999.floor()); // 1
+  /// print(2.0.floor()); // 2
+  /// print(2.99999.floor()); // 2
+  /// print((-1.99999).floor()); // -2
+  /// print((-2.0).floor()); // -2
+  /// print((-2.00001).floor()); // -3
+  /// ```
   int floor();
 
-  /// Returns the least integer which is not smaller than this number.
+  /// Returns the least integer that is not smaller than this number.
   ///
   /// Rounds the number towards infinity.
   ///
   /// Throws an [UnsupportedError] if this number is not finite
-  /// (NaN or an infinity), .
+  /// (NaN or an infinity).
+  /// ```dart
+  /// print(1.99999.ceil()); // 2
+  /// print(2.0.ceil()); // 2
+  /// print(2.00001.ceil()); // 3
+  /// print((-1.99999).ceil()); // -1
+  /// print((-2.0).ceil()); // -2
+  /// print((-2.00001).ceil()); // -2
+  /// ```
   int ceil();
 
   /// Returns the integer obtained by discarding any fractional
@@ -79,7 +107,15 @@
   /// Rounds the number towards zero.
   ///
   /// Throws an [UnsupportedError] if this number is not finite
-  /// (NaN or an infinity), .
+  /// (NaN or an infinity).
+  /// ```dart
+  /// print(2.00001.truncate()); // 2
+  /// print(1.99999.truncate()); // 1
+  /// print(0.5.truncate()); // 0
+  /// print((-0.5).truncate()); // 0
+  /// print((-1.5).truncate()); // -1
+  /// print((-2.5).truncate()); // -2
+  /// ```
   int truncate();
 
   /// Returns the integer double value closest to `this`.
@@ -92,8 +128,15 @@
   ///
   /// For the purpose of rounding, `-0.0` is considered to be below `0.0`,
   /// and `-0.0` is therefore considered closer to negative numbers than `0.0`.
-  /// This means that for a value, `d` in the range `-0.5 < d < 0.0`,
+  /// This means that for a value `d` in the range `-0.5 < d < 0.0`,
   /// the result is `-0.0`.
+  /// ```dart
+  /// print(3.0.roundToDouble()); // 3.0
+  /// print(3.25.roundToDouble()); // 3.0
+  /// print(3.5.roundToDouble()); // 4.0
+  /// print(3.75.roundToDouble()); // 4.0
+  /// print((-3.5).roundToDouble()); // -4.0
+  /// ```
   double roundToDouble();
 
   /// Returns the greatest integer double value no greater than `this`.
@@ -103,6 +146,14 @@
   ///
   /// For the purpose of rounding, `-0.0` is considered to be below `0.0`.
   /// A number `d` in the range `0.0 < d < 1.0` will return `0.0`.
+  /// ```dart
+  /// print(1.99999.floorToDouble()); // 1.0
+  /// print(2.0.floorToDouble()); // 2.0
+  /// print(2.99999.floorToDouble()); // 2.0
+  /// print((-1.99999).floorToDouble()); // -2.0
+  /// print((-2.0).floorToDouble()); // -2.0
+  /// print((-2.00001).floorToDouble()); // -3.0
+  /// ```
   double floorToDouble();
 
   /// Returns the least integer double value no smaller than `this`.
@@ -112,6 +163,14 @@
   ///
   /// For the purpose of rounding, `-0.0` is considered to be below `0.0`.
   /// A number `d` in the range `-1.0 < d < 0.0` will return `-0.0`.
+  /// ```dart
+  /// print(1.99999.ceilToDouble()); // 2.0
+  /// print(2.0.ceilToDouble()); // 2.0
+  /// print(2.00001.ceilToDouble()); // 3.0
+  /// print((-1.99999).ceilToDouble()); // -1.0
+  /// print((-2.0).ceilToDouble()); // -2.0
+  /// print((-2.00001).ceilToDouble()); // -2.0
+  /// ```
   double ceilToDouble();
 
   /// Returns the integer double value obtained by discarding any fractional
@@ -123,6 +182,15 @@
   /// For the purpose of rounding, `-0.0` is considered to be below `0.0`.
   /// A number `d` in the range `-1.0 < d < 0.0` will return `-0.0`, and
   /// in the range `0.0 < d < 1.0` it will return 0.0.
+  /// ```dart
+  /// print(2.5.truncateToDouble()); // 2.0
+  /// print(2.00001.truncateToDouble()); // 2.0
+  /// print(1.99999.truncateToDouble()); // 1.0
+  /// print(0.5.truncateToDouble()); // 0.0
+  /// print((-0.5).truncateToDouble()); // -0.0
+  /// print((-1.5).truncateToDouble()); // -1.0
+  /// print((-2.5).truncateToDouble()); // -2.0
+  /// ```
   double truncateToDouble();
 
   /// Provide a representation of this [double] value.
@@ -139,7 +207,7 @@
   /// `d` is NaN).
   String toString();
 
-  /// Parse [source] as an double literal and return its value.
+  /// Parse [source] as a double literal and return its value.
   ///
   /// Accepts an optional sign (`+` or `-`) followed by either the characters
   /// "Infinity", the characters "NaN" or a floating-point representation.
@@ -176,9 +244,23 @@
   external static double parse(String source,
       [@deprecated double onError(String source)?]);
 
-  /// Parse [source] as an double literal and return its value.
+  /// Parse [source] as a double literal and return its value.
   ///
-  /// Like [parse] except that this function returns `null` for invalid inputs
+  /// Like [parse], except that this function returns `null` for invalid inputs
   /// instead of throwing.
+  ///
+  /// Example:
+  /// ```dart
+  /// var value = double.tryParse('3.14'); // 3.14
+  /// value = double.tryParse('  3.14 \xA0'); // 3.14
+  /// value = double.tryParse('0.'); // 0.0
+  /// value = double.tryParse('.0'); // 0.0
+  /// value = double.tryParse('-1.e3'); // -1000.0
+  /// value = double.tryParse('1234E+7'); // 12340000000.0
+  /// value = double.tryParse('+.12e-9'); // 1.2e-10
+  /// value = double.tryParse('-NaN'); // NaN
+  /// value = double.tryParse('0xFF'); // null
+  /// value = double.tryParse(double.infinity.toString()); // Infinity
+  /// ```
   external static double? tryParse(String source);
 }
diff --git a/sdk/lib/core/duration.dart b/sdk/lib/core/duration.dart
index 1e6b729..11fc5c8 100644
--- a/sdk/lib/core/duration.dart
+++ b/sdk/lib/core/duration.dart
@@ -12,7 +12,7 @@
 ///
 /// Durations are context independent. For example, a duration of 2 days is
 /// always 48 hours, even when it is added to a `DateTime` just when the
-/// time zone is about to do a daylight-savings switch. (See [DateTime.add]).
+/// time zone is about to make a daylight-savings switch. (See [DateTime.add]).
 ///
 /// Despite the same name, a `Duration` object does not implement "Durations"
 /// as specified by ISO 8601. In particular, a duration object does not keep
@@ -20,34 +20,69 @@
 /// only uses these arguments to compute the length of the corresponding time
 /// interval.
 ///
-/// To create a new Duration object, use this class's single constructor
+/// To create a new `Duration` object, use this class's single constructor
 /// giving the appropriate arguments:
 /// ```dart
-/// var fastestMarathon = const Duration(hours: 2, minutes: 3, seconds: 2);
+/// const fastestMarathon = Duration(hours: 2, minutes: 3, seconds: 2);
 /// ```
-/// The [Duration] is the sum of all individual parts.
-/// This means that individual parts can be larger than the next-bigger unit.
-/// For example, [inMinutes] can be greater than 59.
-/// ```dart
-/// const fastestMarathon = const Duration(hours: 2, minutes: 3, seconds: 2);
-/// assert(fastestMarathon.inMinutes == 123);
-/// ```
-/// All individual parts are allowed to be negative.
+/// The [Duration] represents a single number of microseconds,
+/// which is the sum of all the individual arguments to the constructor.
 ///
+/// Properties can access that single number in different ways.
+/// For example the [inMinutes] gives the number of whole minutes
+/// in the total duration, which includes the minutes that were provided
+/// as "hours" to the constructor, and can be larger than 59.
+///
+/// ```dart
+/// const fastestMarathon = Duration(hours: 2, minutes: 3, seconds: 2);
+/// print(fastestMarathon.inDays); // 0
+/// print(fastestMarathon.inHours); // 2
+/// print(fastestMarathon.inMinutes); // 123
+/// print(fastestMarathon.inSeconds); // 7382
+/// print(fastestMarathon.inMilliseconds); // 7382000
+/// ```
+/// The duration can be negative, in which case
+/// all the properties derived from the duration are also non-positive.
+/// ```dart
+/// const overDayAgo = Duration(days: -1, hours: -10);
+/// print(overDayAgo.inDays); // -1
+/// print(overDayAgo.inHours); // -34
+/// print(overDayAgo.inMinutes); // -2040
+/// ```
 /// Use one of the properties, such as [inDays],
-/// to retrieve the integer value of the Duration in the specified time unit.
+/// to retrieve the integer value of the `Duration` in the specified time unit.
 /// Note that the returned value is rounded down.
 /// For example,
 /// ```dart
-/// var aLongWeekend = const Duration(hours: 88);
-/// assert(aLongWeekend.inDays == 3);
+/// const aLongWeekend = Duration(hours: 88);
+/// print(aLongWeekend.inDays); // 3
 /// ```
 /// This class provides a collection of arithmetic
 /// and comparison operators,
 /// plus a set of constants useful for converting time units.
+/// ```dart
+/// const firstHalf = Duration(minutes: 45); // 00:45:00.000000
+/// const secondHalf = Duration(minutes: 45); // 00:45:00.000000
+/// const overTime = Duration(minutes: 30); // 00:30:00.000000
+/// final maxGameTime = firstHalf + secondHalf + overTime;
+/// print(maxGameTime.inMinutes); // 120
 ///
-/// See [DateTime] to represent a point in time.
-/// See [Stopwatch] to measure time-spans.
+/// // The duration of the firstHalf and secondHalf is the same, returns 0.
+/// var result = firstHalf.compareTo(secondHalf);
+/// print(result); // 0
+///
+/// // Duration of overTime is shorter than firstHalf, returns < 0.
+/// result = overTime.compareTo(firstHalf);
+/// print(result); // < 0
+///
+/// // Duration of secondHalf is longer than overTime, returns > 0.
+/// result = secondHalf.compareTo(overTime);
+/// print(result); // > 0
+/// ```
+///
+/// **See also:**
+/// * [DateTime] to represent a point in time.
+/// * [Stopwatch] to measure time-spans.
 class Duration implements Comparable<Duration> {
   /// The number of microseconds per millisecond.
   static const int microsecondsPerMillisecond = 1000;
@@ -130,6 +165,11 @@
   /// and it might lose precision.
   ///
   /// All arguments are 0 by default.
+  /// ```dart
+  /// const duration = Duration(days: 1, hours: 8, minutes: 56, seconds: 59,
+  ///   milliseconds: 30, microseconds: 10);
+  /// print(duration); // 32:56:59.030010
+  /// ```
   const Duration(
       {int days = 0,
       int hours = 0,
@@ -193,41 +233,69 @@
   bool operator >=(Duration other) => this._duration >= other._duration;
 
   /// The number of entire days spanned by this [Duration].
+  ///
+  /// For example, a duration of four days and three hours
+  /// has four entire days.
+  /// ```dart
+  /// const duration = Duration(days: 4, hours: 3);
+  /// print(duration.inDays); // 4
+  /// ```
   int get inDays => _duration ~/ Duration.microsecondsPerDay;
 
   /// The number of entire hours spanned by this [Duration].
   ///
   /// The returned value can be greater than 23.
-  /// For example a duration of four days and three hours
+  /// For example, a duration of four days and three hours
   /// has 99 entire hours.
+  /// ```dart
+  /// const duration = Duration(days: 4, hours: 3);
+  /// print(duration.inHours); // 99
+  /// ```
   int get inHours => _duration ~/ Duration.microsecondsPerHour;
 
   /// The number of whole minutes spanned by this [Duration].
   ///
   /// The returned value can be greater than 59.
-  /// For example a duration of three hours and 12 minutes
+  /// For example, a duration of three hours and 12 minutes
   /// has 192 minutes.
+  /// ```dart
+  /// const duration = Duration(hours: 3, minutes: 12);
+  /// print(duration.inMinutes); // 192
+  /// ```
   int get inMinutes => _duration ~/ Duration.microsecondsPerMinute;
 
   /// The number of whole seconds spanned by this [Duration].
   ///
   /// The returned value can be greater than 59.
-  /// For example a duration of three minutes and 12 seconds
+  /// For example, a duration of three minutes and 12 seconds
   /// has 192 seconds.
+  /// ```dart
+  /// const duration = Duration(minutes: 3, seconds: 12);
+  /// print(duration.inSeconds); // 192
+  /// ```
   int get inSeconds => _duration ~/ Duration.microsecondsPerSecond;
 
   /// The number of whole milliseconds spanned by this [Duration].
   ///
   /// The returned value can be greater than 999.
-  /// For example a duration of three seconds and 125 milliseconds
+  /// For example, a duration of three seconds and 125 milliseconds
   /// has 3125 milliseconds.
+  /// ```dart
+  /// const duration = Duration(seconds: 3, milliseconds: 125);
+  /// print(duration.inMilliseconds); // 3125
+  /// ```
   int get inMilliseconds => _duration ~/ Duration.microsecondsPerMillisecond;
 
   /// The number of whole microseconds spanned by this [Duration].
   ///
   /// The returned value can be greater than 999999.
-  /// For example a duration of three seconds, 125 milliseconds and
+  /// For example, a duration of three seconds, 125 milliseconds and
   /// 369 microseconds has 3125369 microseconds.
+  /// ```dart
+  /// const duration = Duration(seconds: 3, milliseconds: 125,
+  ///     microseconds: 369);
+  /// print(duration.inMicroseconds); // 3125369
+  /// ```
   int get inMicroseconds => _duration;
 
   /// Whether this [Duration] has the same length as [other].
@@ -255,11 +323,11 @@
   /// Returns a string with hours, minutes, seconds, and microseconds, in the
   /// following format: `H:MM:SS.mmmmmm`. For example,
   /// ```dart
-  /// var d = Duration(days: 1, hours: 1, minutes: 33, microseconds: 500);
-  /// d.toString();  // "25:33:00.000500"
+  /// var d = const Duration(days: 1, hours: 1, minutes: 33, microseconds: 500);
+  /// print(d.toString()); // 25:33:00.000500
   ///
-  /// d = Duration(days: 0, hours: 1, minutes: 10, microseconds: 500);
-  /// d.toString();  // "1:10:00.000500"
+  /// d = const Duration(hours: 1, minutes: 10, microseconds: 500);
+  /// print(d.toString()); // 1:10:00.000500
   /// ```
   String toString() {
     var microseconds = inMicroseconds;
diff --git a/sdk/lib/core/int.dart b/sdk/lib/core/int.dart
index ccf2775..32c6682 100644
--- a/sdk/lib/core/int.dart
+++ b/sdk/lib/core/int.dart
@@ -20,6 +20,11 @@
 /// operands to 32-bit integers when compiled to JavaScript.
 ///
 /// Classes cannot extend, implement, or mix in `int`.
+///
+/// **See also:**
+/// * [num] the super class for [int].
+/// * [Numbers](https://dart.dev/guides/language/numbers) in
+/// [A tour of the Dart language](https://dart.dev/guides/language/language-tour).
 abstract class int extends num {
   /// Returns the integer value of the given environment declaration [name].
   ///
@@ -59,6 +64,11 @@
   ///
   /// If both operands are negative, the result is negative, otherwise
   /// the result is non-negative.
+  /// ```dart
+  /// print((2 & 1).toRadixString(2)); // 0010 & 0001 -> 0000
+  /// print((3 & 1).toRadixString(2)); // 0011 & 0001 -> 0001
+  /// print((10 & 2).toRadixString(2)); // 1010 & 0010 -> 0010
+  /// ```
   int operator &(int other);
 
   /// Bit-wise or operator.
@@ -69,6 +79,13 @@
   ///
   /// If both operands are non-negative, the result is non-negative,
   /// otherwise the result is negative.
+  ///
+  /// Example:
+  /// ```dart
+  /// print((2 | 1).toRadixString(2)); // 0010 | 0001 -> 0011
+  /// print((3 | 1).toRadixString(2)); // 0011 | 0001 -> 0011
+  /// print((10 | 2).toRadixString(2)); // 1010 | 0010 -> 1010
+  /// ```
   int operator |(int other);
 
   /// Bit-wise exclusive-or operator.
@@ -79,6 +96,13 @@
   ///
   /// If the operands have the same sign, the result is non-negative,
   /// otherwise the result is negative.
+  ///
+  /// Example:
+  /// ```dart
+  /// print((2 ^ 1).toRadixString(2)); //  0010 ^ 0001 -> 0011
+  /// print((3 ^ 1).toRadixString(2)); //  0011 ^ 0001 -> 0010
+  /// print((10 ^ 2).toRadixString(2)); //  1010 ^ 0010 -> 1000
+  /// ```
   int operator ^(int other);
 
   /// The bit-wise negate operator.
@@ -99,15 +123,31 @@
   /// mask.
   ///
   /// It is an error if [shiftAmount] is negative.
+  ///
+  /// Example:
+  /// ```dart
+  /// print((3 << 1).toRadixString(2)); // 0011 -> 0110
+  /// print((9 << 2).toRadixString(2)); // 1001 -> 100100
+  /// print((10 << 3).toRadixString(2)); // 1010 -> 1010000
+  /// ```
   int operator <<(int shiftAmount);
 
   /// Shift the bits of this integer to the right by [shiftAmount].
   ///
   /// Shifting to the right makes the number smaller and drops the least
   /// significant bits, effectively doing an integer division by
-  ///`pow(2, shiftIndex)`.
+  /// `pow(2, shiftIndex)`.
   ///
   /// It is an error if [shiftAmount] is negative.
+  ///
+  /// Example:
+  /// ```dart
+  /// print((3 >> 1).toRadixString(2)); // 0011 -> 0001
+  /// print((9 >> 2).toRadixString(2)); // 1001 -> 0010
+  /// print((10 >> 3).toRadixString(2)); // 1010 -> 0001
+  /// print((-6 >> 2).toRadixString); // 111...1010 -> 111...1110 == -2
+  /// print((-85 >> 3).toRadixString); // 111...10101011 -> 111...11110101 == -11
+  /// ```
   int operator >>(int shiftAmount);
 
   /// Bitwise unsigned right shift by [shiftAmount] bits.
@@ -117,6 +157,13 @@
   /// and zero-bits are shifted in as the new most significant bits.
   ///
   /// The [shiftAmount] must be non-negative.
+  ///
+  /// Example:
+  /// ```dart
+  /// print((3 >>> 1).toRadixString(2)); // 0011 -> 0001
+  /// print((9 >>> 2).toRadixString(2)); // 1001 -> 0010
+  /// print(((-9) >>> 2).toRadixString(2)); // 111...1011 -> 001...1110 (> 0)
+  /// ```
   int operator >>>(int shiftAmount);
 
   /// Returns this integer to the power of [exponent] modulo [modulus].
@@ -144,6 +191,15 @@
   /// For any integer `x`, `x.gcd(x)` is `x.abs()`.
   ///
   /// If both `this` and `other` is zero, the result is also zero.
+  ///
+  /// Example:
+  /// ```dart
+  /// print(4.gcd(2)); // 2
+  /// print(8.gcd(4)); // 4
+  /// print(10.gcd(12)); // 2
+  /// print(10.gcd(0)); // 10
+  /// print((-2).gcd(-3)); // 1
+  /// ```
   int gcd(int other);
 
   /// Returns true if and only if this integer is even.
@@ -196,8 +252,8 @@
   int toUnsigned(int width);
 
   /// Returns the least significant [width] bits of this integer, extending the
-  /// highest retained bit to the sign.  This is the same as truncating the value
-  /// to fit in [width] bits using an signed 2-s complement representation.  The
+  /// highest retained bit to the sign. This is the same as truncating the value
+  /// to fit in [width] bits using an signed 2-s complement representation. The
   /// returned value has the same bit value in all positions higher than [width].
   ///
   /// ```dart
@@ -276,9 +332,28 @@
   /// Converts [this] to a string representation in the given [radix].
   ///
   /// In the string representation, lower-case letters are used for digits above
-  /// '9', with 'a' being 10 an 'z' being 35.
+  /// '9', with 'a' being 10 and 'z' being 35.
   ///
   /// The [radix] argument must be an integer in the range 2 to 36.
+  ///
+  /// Example:
+  /// ```dart
+  /// // Binary (base 2).
+  /// print(12.toRadixString(2)); // 1100
+  /// print(31.toRadixString(2)); // 11111
+  /// print(2021.toRadixString(2)); // 11111100101
+  /// print((-12).toRadixString(2)); // -1100
+  /// // Octal (base 8).
+  /// print(12.toRadixString(8)); // 14
+  /// print(31.toRadixString(8)); // 37
+  /// print(2021.toRadixString(8)); // 3745
+  /// // Hexadecimal (base 16).
+  /// print(12.toRadixString(16)); // c
+  /// print(31.toRadixString(16)); // 1f
+  /// print(2021.toRadixString(16)); // 7e5
+  /// // Base 36.
+  /// print((35 * 36 + 1).toRadixString(36)); // z1
+  /// ```
   String toRadixString(int radix);
 
   /// Parse [source] as a, possibly signed, integer literal and return its value.
@@ -309,6 +384,7 @@
   ///
   /// Instead of throwing and immediately catching the [FormatException],
   /// instead use [tryParse] to handle a parsing error.
+  ///
   /// Example:
   /// ```dart
   /// var value = int.tryParse(text);
@@ -333,5 +409,29 @@
   ///
   /// Like [parse] except that this function returns `null` where a
   /// similar call to [parse] would throw a [FormatException].
+  ///
+  /// Example:
+  /// ```dart
+  /// print(int.tryParse('2021')); // 2021
+  /// print(int.tryParse('1f')); // null
+  /// // From binary (base 2) value.
+  /// print(int.tryParse('1100', radix: 2)); // 12
+  /// print(int.tryParse('00011111', radix: 2)); // 31
+  /// print(int.tryParse('011111100101', radix: 2)); // 2021
+  /// // From octal (base 8) value.
+  /// print(int.tryParse('14', radix: 8)); // 12
+  /// print(int.tryParse('37', radix: 8)); // 31
+  /// print(int.tryParse('3745', radix: 8)); // 2021
+  /// // From hexadecimal (base 16) value.
+  /// print(int.tryParse('c', radix: 16)); // 12
+  /// print(int.tryParse('1f', radix: 16)); // 31
+  /// print(int.tryParse('7e5', radix: 16)); // 2021
+  /// // From base 35 value.
+  /// print(int.tryParse('y1', radix: 35)); // 1191 == 34 * 35 + 1
+  /// print(int.tryParse('z1', radix: 35)); // null
+  /// // From base 36 value.
+  /// print(int.tryParse('y1', radix: 36)); // 1225 == 34 * 36 + 1
+  /// print(int.tryParse('z1', radix: 36)); // 1261 == 35 * 36 + 1
+  /// ```
   external static int? tryParse(String source, {int? radix});
 }
diff --git a/sdk/lib/core/iterable.dart b/sdk/lib/core/iterable.dart
index 0b42ab7..41d7e23 100644
--- a/sdk/lib/core/iterable.dart
+++ b/sdk/lib/core/iterable.dart
@@ -162,6 +162,13 @@
   /// The returned iterable will provide the same elements as this iterable,
   /// and, after that, the elements of [other], in the same order as in the
   /// original iterables.
+  ///
+  /// Example:
+  /// ```dart
+  /// var planets = <String>['Earth', 'Jupiter'];
+  /// var updated = planets.followedBy(['Mars', 'Venus']);
+  /// print(updated); // (Earth, Jupiter, Mars, Venus)
+  /// ```
   Iterable<E> followedBy(Iterable<E> other) {
     var self = this; // TODO(lrn): Remove when we can promote `this`.
     if (self is EfficientLengthIterable<E>) {
@@ -189,13 +196,24 @@
   /// For example, [elementAt] may call `toElement` only once.
   ///
   /// Equivalent to:
-  /// ```dart
+  /// ```
   /// Iterable<T> map<T>(T toElement(E e)) sync* {
   ///   for (var value in this) {
   ///     yield toElement(value);
   ///   }
   /// }
   /// ```
+  /// Example:
+  /// ```dart import:convert
+  /// var products = jsonDecode('''
+  /// [
+  ///   {"name": "Screwdriver", "price": 42.00},
+  ///   {"name": "Wingnut", "price": 0.50}
+  /// ]
+  /// ''');
+  /// var values = products.map((product) => product['price'] as double);
+  /// var totalPrice = values.fold(0.0, (a, b) => a + b); // 42.5.
+  /// ```
   Iterable<T> map<T>(T toElement(E e)) => MappedIterable<E, T>(this, toElement);
 
   /// Returns a new lazy [Iterable] with all elements that satisfy the
@@ -210,6 +228,14 @@
   /// Iterating will not cache results, and thus iterating multiple times over
   /// the returned [Iterable] may invoke the supplied
   /// function [test] multiple times on the same element.
+  ///
+  /// Example:
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3, 5, 6, 7];
+  /// var result = numbers.where((x) => x < 5); // (1, 2, 3)
+  /// result = numbers.where((x) => x > 5); // (6, 7)
+  /// result = numbers.where((x) => x.isEven); // (2, 6)
+  /// ```
   Iterable<E> where(bool test(E element)) => WhereIterable<E>(this, test);
 
   /// Returns a new lazy [Iterable] with all elements that have type [T].
@@ -233,17 +259,18 @@
   ///
   /// Example:
   /// ```dart
-  /// var pairs = [[1, 2], [3, 4]];
-  /// var flattened = pairs.expand((pair) => pair).toList();
-  /// print(flattened); // => [1, 2, 3, 4];
+  /// Iterable<int> count(int n) sync* {
+  ///   for (var i = 1; i <= n; i++) {
+  ///     yield i;
+  ///    }
+  ///  }
   ///
-  /// var input = [1, 2, 3];
-  /// var duplicated = input.expand((i) => [i, i]).toList();
-  /// print(duplicated); // => [1, 1, 2, 2, 3, 3]
+  /// var numbers = [1, 3, 0, 2];
+  /// print(numbers.expand(count)); // (1, 1, 2, 3, 1, 2)
   /// ```
   ///
   /// Equivalent to:
-  /// ```dart
+  /// ```
   /// Iterable<T> expand<T>(Iterable<T> toElements(E e)) sync* {
   ///   for (var value in this) {
   ///     yield* toElements(value);
@@ -267,6 +294,15 @@
   /// (see [Set.identity]) that its `contains` uses.
   /// Likewise the `Iterable` returned by a [Map.keys] call
   /// should use the same equality that the `Map` uses for keys.
+  ///
+  /// Example:
+  /// ```dart
+  /// final gasPlanets = <int, String>{1: 'Jupiter', 2: 'Saturn'};
+  /// final containsOne = gasPlanets.keys.contains(1); // true
+  /// final containsFive = gasPlanets.keys.contains(5); // false
+  /// final containsJupiter = gasPlanets.values.contains('Jupiter'); // true
+  /// final containsMercury = gasPlanets.values.contains('Mercury'); // false
+  /// ```
   bool contains(Object? element) {
     for (E e in this) {
       if (e == element) return true;
@@ -275,6 +311,16 @@
   }
 
   /// Invokes [action] on each element of this iterable in iteration order.
+  ///
+  /// Example:
+  /// ```dart
+  /// final numbers = <int>[1, 2, 6, 7];
+  /// numbers.forEach(print);
+  /// // 1
+  /// // 2
+  /// // 6
+  /// // 7
+  /// ```
   void forEach(void action(E element)) {
     for (E element in this) action(element);
   }
@@ -288,7 +334,7 @@
   /// Otherwise this method starts with the first element from the iterator,
   /// and then combines it with the remaining elements in iteration order,
   /// as if by:
-  /// ```dart
+  /// ```
   /// E value = iterable.first;
   /// iterable.skip(1).forEach((element) {
   ///   value = combine(value, element);
@@ -297,7 +343,9 @@
   /// ```
   /// Example of calculating the sum of an iterable:
   /// ```dart
-  /// iterable.reduce((value, element) => value + element);
+  /// final numbers = <double>[10, 2, 5, 0.5];
+  /// final result = numbers.reduce((value, element) => value + element);
+  /// print(result); // 17.5
   /// ```
   E reduce(E combine(E value, E element)) {
     Iterator<E> iterator = this.iterator;
@@ -317,7 +365,7 @@
   /// Uses [initialValue] as the initial value,
   /// then iterates through the elements and updates the value with
   /// each element using the [combine] function, as if by:
-  /// ```dart
+  /// ```
   /// var value = initialValue;
   /// for (E element in this) {
   ///   value = combine(value, element);
@@ -326,7 +374,11 @@
   /// ```
   /// Example of calculating the sum of an iterable:
   /// ```dart
-  /// iterable.fold(0, (prev, element) => prev + element);
+  /// final numbers = <double>[10, 2, 5, 0.5];
+  /// const initialValue = 100.0;
+  /// final result = numbers.fold<double>(
+  ///     initialValue, (previousValue, element) => previousValue + element);
+  /// print(result); // 117.5
   /// ```
   T fold<T>(T initialValue, T combine(T previousValue, E element)) {
     var value = initialValue;
@@ -338,6 +390,14 @@
   ///
   /// Checks every element in iteration order, and returns `false` if
   /// any of them make [test] return `false`, otherwise returns `true`.
+  ///
+  /// Example:
+  /// ```dart
+  /// final planetsByMass = <double, String>{0.06: 'Mercury', 0.81: 'Venus',
+  ///   0.11: 'Mars'};
+  /// // Checks whether all keys are smaller than 1.
+  /// final every = planetsByMass.keys.every((key) => key < 1.0); // true
+  /// ```
   bool every(bool test(E element)) {
     for (E element in this) {
       if (!test(element)) return false;
@@ -351,6 +411,13 @@
   /// converts each one to a [String] by calling [Object.toString],
   /// and then concatenates the strings, with the
   /// [separator] string interleaved between the elements.
+  ///
+  /// Example:
+  /// ```dart
+  /// final planetsByMass = <double, String>{0.06: 'Mercury', 0.81: 'Venus',
+  ///   0.11: 'Mars'};
+  /// final joinedNames = planetsByMass.values.join('-'); // Mercury-Venus-Mars
+  /// ```
   String join([String separator = ""]) {
     Iterator<E> iterator = this.iterator;
     if (!iterator.moveNext()) return "";
@@ -373,6 +440,13 @@
   ///
   /// Checks every element in iteration order, and returns `true` if
   /// any of them make [test] return `true`, otherwise returns false.
+  ///
+  /// Example:
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3, 5, 6, 7];
+  /// var result = numbers.any((element) => element >= 5); // true;
+  /// result = numbers.any((element) => element >= 10); // false;
+  /// ```
   bool any(bool test(E element)) {
     for (E element in this) {
       if (test(element)) return true;
@@ -384,6 +458,14 @@
   ///
   /// The elements are in iteration order.
   /// The list is fixed-length if [growable] is false.
+  ///
+  /// Example:
+  /// ```dart
+  /// final planets = <int, String>{1: 'Mercury', 2: 'Venus', 3: 'Mars'};
+  /// final keysList = planets.keys.toList(growable: false); // [1, 2, 3]
+  /// final valuesList =
+  ///     planets.values.toList(growable: false); // [Mercury, Venus, Mars]
+  /// ```
   List<E> toList({bool growable = true}) {
     return List<E>.of(this, growable: growable);
   }
@@ -395,6 +477,12 @@
   /// or it contains one or more elements that are equal.
   /// The order of the elements in the set is not guaranteed to be the same
   /// as for the iterable.
+  ///
+  /// Example:
+  /// ```dart
+  /// final planets = <int, String>{1: 'Mercury', 2: 'Venus', 3: 'Mars'};
+  /// final valueSet = planets.values.toSet(); // {Mercury, Venus, Mars}
+  /// ```
   Set<E> toSet() => Set<E>.of(this);
 
   /// Returns the number of elements in [this].
@@ -415,11 +503,25 @@
   /// Whether this collection has no elements.
   ///
   /// May be computed by checking if `iterator.moveNext()` returns `false`.
+  ///
+  /// Example:
+  /// ```dart
+  /// final emptyList = <int>[];
+  /// print(emptyList.isEmpty); // true;
+  /// print(emptyList.iterator.moveNext()); // false
+  /// ```
   bool get isEmpty => !iterator.moveNext();
 
   /// Whether this collection has at least one element.
   ///
   /// May be computed by checking if `iterator.moveNext()` returns `true`.
+  ///
+  /// Example:
+  /// ```dart
+  /// final numbers = <int>{1, 2, 3};
+  /// print(numbers.isNotEmpty); // true;
+  /// print(numbers.iterator.moveNext()); // true
+  /// ```
   bool get isNotEmpty => !isEmpty;
 
   /// Returns a lazy iterable of the [count] first elements of this iterable.
@@ -431,6 +533,13 @@
   /// elements have been seen.
   ///
   /// The `count` must not be negative.
+  ///
+  /// Example:
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3, 5, 6, 7];
+  /// final result = numbers.take(4); // (1, 2, 3, 5)
+  /// final takeAll = numbers.take(100); // (1, 2, 3, 5, 6, 7)
+  /// ```
   Iterable<E> take(int count) {
     return TakeIterable<E>(this, count);
   }
@@ -443,6 +552,15 @@
   /// The elements can be computed by stepping through [iterator] until an
   /// element is found where `test(element)` is false. At that point,
   /// the returned iterable stops (its `moveNext()` returns false).
+  ///
+  /// Example:
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3, 5, 6, 7];
+  /// var result = numbers.takeWhile((x) => x < 5); // (1, 2, 3)
+  /// result = numbers.takeWhile((x) => x != 3); // (1, 2)
+  /// result = numbers.takeWhile((x) => x != 4); // (1, 2, 3, 5, 6, 7)
+  /// result = numbers.takeWhile((x) => x.isOdd); // (1)
+  /// ```
   Iterable<E> takeWhile(bool test(E value)) {
     return TakeWhileIterable<E>(this, test);
   }
@@ -460,6 +578,13 @@
   /// through earlier elements, for example when iterating a [List].
   /// Such iterables are allowed to ignore the initial skipped elements.
   ///
+  /// Example:
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3, 5, 6, 7];
+  /// final result = numbers.skip(4); // (6, 7)
+  /// final skipAll = numbers.skip(100); // () - no elements.
+  /// ```
+  ///
   /// The [count] must not be negative.
   Iterable<E> skip(int count) {
     return SkipIterable<E>(this, count);
@@ -475,6 +600,15 @@
   /// true. If all elements satisfy `test` the resulting iterable is empty,
   /// otherwise it iterates the remaining elements in their original order,
   /// starting with the first element for which `test(element)` returns `false`.
+  ///
+  /// Example:
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3, 5, 6, 7];
+  /// var result = numbers.skipWhile((x) => x < 5); // (5, 6, 7)
+  /// result = numbers.skipWhile((x) => x != 3); // (3, 5, 6, 7)
+  /// result = numbers.skipWhile((x) => x != 4); // ()
+  /// result = numbers.skipWhile((x) => x.isOdd); // (2, 3, 5, 6, 7)
+  /// ```
   Iterable<E> skipWhile(bool test(E value)) {
     return SkipWhileIterable<E>(this, test);
   }
@@ -527,6 +661,15 @@
   ///
   /// Iterates through elements and returns the first to satisfy [test].
   ///
+  /// Example:
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3, 5, 6, 7];
+  /// var result = numbers.firstWhere((element) => element < 5); // 1
+  /// result = numbers.firstWhere((element) => element > 5); // 6
+  /// result =
+  ///     numbers.firstWhere((element) => element > 10, orElse: () => -1); // -1
+  /// ```
+  ///
   /// If no element satisfies [test], the result of invoking the [orElse]
   /// function is returned.
   /// If [orElse] is omitted, it defaults to throwing a [StateError].
@@ -547,6 +690,15 @@
   /// checks `test(element)` for each,
   /// and finally returns that last one that matched.
   ///
+  /// Example:
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3, 5, 6, 7];
+  /// var result = numbers.lastWhere((element) => element < 5); // 3
+  /// result = numbers.lastWhere((element) => element > 5); // 7
+  /// result = numbers.lastWhere((element) => element > 10,
+  ///     orElse: () => -1); // -1
+  /// ```
+  ///
   /// If no element satisfies [test], the result of invoking the [orElse]
   /// function is returned.
   /// If [orElse] is omitted, it defaults to throwing a [StateError].
@@ -571,6 +723,22 @@
   /// If more than one matching element is found, throws [StateError].
   /// If no matching element is found, returns the result of [orElse].
   /// If [orElse] is omitted, it defaults to throwing a [StateError].
+  ///
+  /// Example:
+  /// ```dart
+  /// final numbers = <int>[2, 2, 10];
+  /// var result = numbers.singleWhere((element) => element > 5); // 10
+  /// ```
+  /// When no matching element is found, the result of calling [orElse] is
+  /// returned instead.
+  /// ```dart continued
+  /// result = numbers.singleWhere((element) => element == 1,
+  ///     orElse: () => -1); // -1
+  /// ```
+  /// There must not be more than one matching element.
+  /// ```dart continued
+  /// result = numbers.singleWhere((element) => element == 2); // Throws Error.
+  /// ```
   E singleWhere(bool test(E element), {E orElse()?}) {
     late E result;
     bool foundMatching = false;
@@ -597,6 +765,12 @@
   /// May iterate through the elements in iteration order, ignoring the
   /// first [index] elements and then returning the next.
   /// Some iterables may have a more efficient way to find the element.
+  ///
+  /// Example:
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3, 5, 6, 7];
+  /// final elementAt = numbers.elementAt(4); // 6
+  /// ```
   E elementAt(int index) {
     RangeError.checkNotNegative(index, "index");
     int elementIndex = 0;
diff --git a/sdk/lib/core/list.dart b/sdk/lib/core/list.dart
index 1c51340..bc3ac77 100644
--- a/sdk/lib/core/list.dart
+++ b/sdk/lib/core/list.dart
@@ -9,11 +9,14 @@
 /// Subclasses of this class implement different kinds of lists.
 /// The most common kinds of lists are:
 ///
-/// * Fixed-length list.
+/// * **Fixed-length list**
+///
 ///   An error occurs when attempting to use operations
 ///   that can change the length of the list.
 ///
-/// * Growable list. Full implementation of the API defined in this class.
+/// * **Growable list**
+///
+///   Full implementation of the API defined in this class.
 ///
 /// The default growable list, as created by `[]`, keeps
 /// an internal buffer, and grows that buffer when necessary. This guarantees
@@ -23,18 +26,78 @@
 /// operation will need to immediately increase the buffer capacity.
 /// Other list implementations may have different performance behavior.
 ///
-/// The following code illustrates that some List implementations support
-/// only a subset of the API.
+/// Example of fixed-length list:
 /// ```dart
-/// var fixedLengthList = List<int>.filled(5, 0);
-/// fixedLengthList.length = 0;  // Error
-/// fixedLengthList.add(499);    // Error
+/// final fixedLengthList = List<int>.filled(5, 0); // Creates fixed-length list.
+/// print(fixedLengthList); // [0, 0, 0, 0, 0]
 /// fixedLengthList[0] = 87;
-/// var growableList = [1, 2];
-/// growableList.length = 0;
-/// growableList.add(499);
-/// growableList[0] = 87;
+/// fixedLengthList.setAll(1, [1, 2, 3]);
+/// print(fixedLengthList); // [87, 1, 2, 3, 0]
+/// // Fixed length list length can't be changed or increased
+/// fixedLengthList.length = 0;  // Throws
+/// fixedLengthList.add(499);    // Throws
 /// ```
+///
+/// Example of growable list:
+/// ```dart
+/// final growableList = <String>['A', 'B']; // Creates growable list.
+/// ```
+/// To add data to the growable list, use [operator[]=], [add] or [addAll].
+/// ```
+/// growableList[0] = 'G';
+/// print(growableList); // [G, B]
+/// growableList.add('X');
+/// growableList.addAll({'C', 'B'});
+/// print(growableList); // [G, B, X, C, B]
+/// ```
+/// To check whether, and where, the element is in the list, use [indexOf] or
+/// [lastIndexOf].
+/// ```
+/// final indexA = growableList.indexOf('A'); // -1 (not in the list)
+/// final firstIndexB = growableList.indexOf('B'); // 1
+/// final lastIndexB = growableList.lastIndexOf('B'); // 4
+/// ```
+/// To remove an element from the growable list, use [remove], [removeAt],
+/// [removeLast], [removeRange] or [removeWhere].
+/// ```
+/// growableList.remove('C');
+/// growableList.removeLast();
+/// print(growableList); // [G, B, X]
+/// ```
+/// To insert an element at position in the list, use [insert] or [insertAll].
+/// ```
+/// growableList.insert(1, 'New');
+/// print(growableList); // [G, New, B, X]
+/// ```
+/// To replace a range of elements in the list, use [fillRange], [replaceRange]
+/// or [setRange].
+/// ```
+/// growableList.replaceRange(0, 2, ['AB', 'A']);
+/// print(growableList); // [AB, A, B, X]
+/// growableList.fillRange(2, 4, 'F');
+/// print(growableList); // [AB, A, F, F]
+/// ```
+/// To sort the elements of the list, use [sort].
+/// ```
+/// growableList.sort((a, b) => a.compareTo(b));
+/// print(growableList); // [A, AB, F, F]
+/// ```
+/// To shuffle the elements of this list randomly, use [shuffle].
+/// ```
+/// growableList.shuffle();
+/// print(growableList); // e.g. [AB, F, A, F]
+/// ```
+/// To find the first element satisfying some predicate, or give a default
+/// value if none do, use [firstWhere].
+/// ```
+/// bool isVowel(String char) => char.length == 1 && "AEIOU".contains(char);
+/// final firstVowel = growableList.firstWhere(isVowel, orElse: () => ''); // ''
+/// ```
+/// There are similar [lastWhere] and [singleWhere] methods.
+///
+/// A list is an [Iterable] and supports all its methods, including
+/// [where], [map], [whereType] and [toList].
+///
 /// Lists are [Iterable]. Iteration occurs over values in index order. Changing
 /// the values does not affect iteration, but changing the valid
 /// indices&mdash;that is, changing the list's length&mdash;between iteration
@@ -52,7 +115,7 @@
 abstract class List<E> implements EfficientLengthIterable<E> {
   /// Creates a list of the given length.
   ///
-  /// **NOTICE**: This constructor cannot be used in null-safe code.
+  /// **NOTE**: This constructor cannot be used in null-safe code.
   /// Use [List.filled] to create a non-empty list.
   /// This requires a fill value to initialize the list elements with.
   /// To create an empty list, use `[]` for a growable list or
@@ -93,7 +156,7 @@
   ///
   /// Example:
   /// ```dart
-  /// List<int>.filled(3, 0, growable: true); // [0, 0, 0]
+  /// final zeroList = List<int>.filled(3, 0, growable: true); // [0, 0, 0]
   /// ```
   ///
   /// The created list is fixed-length if [growable] is false (the default)
@@ -106,16 +169,16 @@
   ///
   /// All elements of the created list share the same [fill] value.
   /// ```dart
-  /// var shared = List.filled(3, []);
+  /// final shared = List.filled(3, []);
   /// shared[0].add(499);
-  /// print(shared);  // => [[499], [499], [499]]
+  /// print(shared);  // [[499], [499], [499]]
   /// ```
   /// You can use [List.generate] to create a list with a fixed length
   /// and a new object at each position.
   /// ```dart
-  /// var unique = List.generate(3, (_) => []);
+  /// final unique = List.generate(3, (_) => []);
   /// unique[0].add(499);
-  /// print(unique); // => [[499], [], []]
+  /// print(unique); // [[499], [], []]
   /// ```
   external factory List.filled(int length, E fill, {bool growable = false});
 
@@ -124,6 +187,13 @@
   /// If [growable] is `false`, which is the default,
   /// the list is a fixed-length list of length zero.
   /// If [growable] is `true`, the list is growable and equivalent to `<E>[]`.
+  /// ```dart
+  /// final growableList = List.empty(growable: true); // []
+  /// growableList.add(1); // [1]
+  ///
+  /// final fixedLengthList = List.empty(growable: false);
+  /// fixedLengthList.add(1); // error
+  /// ```
   @Since("2.9")
   external factory List.empty({bool growable = false});
 
@@ -132,12 +202,24 @@
   /// The [Iterator] of [elements] provides the order of the elements.
   ///
   /// All the [elements] should be instances of [E].
+  ///
+  /// Example:
+  /// ```dart
+  /// final numbers = <num>[1, 2, 3];
+  /// final listFrom = List<int>.from(numbers);
+  /// print(listFrom); // [1, 2, 3]
+  /// ```
   /// The `elements` iterable itself may have any element type, so this
   /// constructor can be used to down-cast a `List`, for example as:
-  /// ```dart
-  /// List<dynamic> dynList = ...some JSON value...;
-  /// List<Map<String, dynamic>> fooList =
-  ///     List.from(dynList.where((x) => x is Map && x["kind"] == "foo"));
+  /// ```dart import:convert
+  /// const jsonArray = '''
+  ///   [{"text": "foo", "value": 1, "status": true},
+  ///    {"text": "bar", "value": 2, "status": false}]
+  /// ''';
+  /// final List<dynamic> dynamicList = jsonDecode(jsonArray);
+  /// final List<Map<String, dynamic>> fooData =
+  ///     List.from(dynamicList.where((x) => x is Map && x['text'] == 'foo'));
+  /// print(fooData); // [{text: foo, value: 1, status: true}]
   /// ```
   ///
   /// This constructor creates a growable list when [growable] is true;
@@ -150,6 +232,11 @@
   ///
   /// This constructor creates a growable list when [growable] is true;
   /// otherwise, it returns a fixed-length list.
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3];
+  /// final listOf = List<num>.of(numbers);
+  /// print(listOf); // [1, 2, 3]
+  /// ```
   external factory List.of(Iterable<E> elements, {bool growable = true});
 
   /// Generates a list of values.
@@ -158,7 +245,13 @@
   /// calling [generator] for each index in the range `0` .. `length - 1`
   /// in increasing order.
   /// ```dart
-  /// List<int>.generate(3, (int index) => index * index); // [0, 1, 4]
+  /// final growableList =
+  ///     List<int>.generate(3, (int index) => index * index, growable: true);
+  /// print(growableList); // [0, 1, 4]
+  ///
+  /// final fixedLengthList =
+  ///     List<int>.generate(3, (int index) => index * index, growable: false);
+  /// print(fixedLengthList); // [0, 1, 4]
   /// ```
   /// The created list is fixed-length if [growable] is set to false.
   ///
@@ -173,6 +266,11 @@
   /// An unmodifiable list cannot have its length or elements changed.
   /// If the elements are themselves immutable, then the resulting list
   /// is also immutable.
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3];
+  /// final unmodifiableList = List.unmodifiable(numbers); // [1, 2, 3]
+  /// unmodifiableList[1] = 87; // Throws.
+  /// ```
   external factory List.unmodifiable(Iterable elements);
 
   /// Adapts [source] to be a `List<T>`.
@@ -203,7 +301,7 @@
   /// If [start] is omitted, it defaults to zero.
   /// If [end] is omitted, it defaults to [source].length.
   ///
-  /// If [source] and [target] is the same list, overlapping source and target
+  /// If [source] and [target] are the same list, overlapping source and target
   /// ranges are respected so that the target range ends up containing the
   /// initial content of the source range.
   /// Otherwise the order of element copying is not guaranteed.
@@ -262,8 +360,8 @@
   /// that is not an instance of [R], the access will throw instead.
   ///
   /// Elements added to the list (e.g., by using [add] or [addAll])
-  /// must be instance of [R] to be valid arguments to the adding function,
-  /// and they must be instances of [E] as well to be accepted by
+  /// must be instances of [R] to be valid arguments to the adding function,
+  /// and they must also be instances of [E] to be accepted by
   /// this list as well.
   ///
   /// Methods which accept `Object?` as argument, like [contains] and [remove],
@@ -289,64 +387,120 @@
   /// less than [length].
   void operator []=(int index, E value);
 
-  /// Updates the first position of the list to contain [value].
+  /// The first element of the list.
   ///
-  /// Equivalent to `theList[0] = value;`.
+  /// The list must be non-empty when accessing its first element.
   ///
-  /// The list must be non-empty.
+  /// The first element of a list can be modified, unlike an [Iterable].
+  /// A `list.first` is equivalent to `list[0]`,
+  /// both for getting and setting the value.
+  ///
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3];
+  /// print(numbers.first); // 1
+  /// numbers.first = 10;
+  /// print(numbers.first); // 10
+  /// numbers.clear();
+  /// numbers.first; // Throws.
+  /// ```
   void set first(E value);
 
-  /// Updates the last position of the list to contain [value].
+  /// The last element of the list.
   ///
-  /// Equivalent to `theList[theList.length - 1] = value;`.
+  /// The list must be non-empty when accessing its last element.
   ///
-  /// The list must be non-empty.
+  /// The last element of a list can be modified, unlike an [Iterable].
+  /// A `list.last` is equivalent to `theList[theList.length - 1]`,
+  /// both for getting and setting the value.
+  ///
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3];
+  /// print(numbers.last); // 3
+  /// numbers.last = 10;
+  /// print(numbers.last); // 10
+  /// numbers.clear();
+  /// numbers.last; // Throws.
+  /// ```
   void set last(E value);
 
   /// The number of objects in this list.
   ///
   /// The valid indices for a list are `0` through `length - 1`.
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3];
+  /// print(numbers.length); // 3
+  /// ```
   int get length;
 
-  /// Changes the length of this list.
+  /// Setting the `length` changes the number of elements in the list.
   ///
   /// The list must be growable.
   /// If [newLength] is greater than current length,
   /// new entries are initialized to `null`,
   /// so [newLength] must not be greater than the current length
   /// if the element type [E] is non-nullable.
+  ///
+  /// ```dart
+  /// final maybeNumbers = <int?>[1, null, 3];
+  /// maybeNumbers.length = 5;
+  /// print(maybeNumbers); // [1, null, 3, null, null]
+  /// maybeNumbers.length = 2;
+  /// print(maybeNumbers); // [1, null]
+  ///
+  /// final numbers = <int>[1, 2, 3];
+  /// numbers.length = 1;
+  /// print(numbers); // [1]
+  /// numbers.length = 5; // Throws, cannot add `null`s.
+  /// ```
   set length(int newLength);
 
   /// Adds [value] to the end of this list,
   /// extending the length by one.
   ///
   /// The list must be growable.
+  ///
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3];
+  /// numbers.add(4);
+  /// print(numbers); // [1, 2, 3, 4]
+  /// ```
   void add(E value);
 
   /// Appends all objects of [iterable] to the end of this list.
   ///
   /// Extends the length of the list by the number of objects in [iterable].
   /// The list must be growable.
+  ///
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3];
+  /// numbers.addAll([4, 5, 6]);
+  /// print(numbers); // [1, 2, 3, 4, 5, 6]
+  /// ```
   void addAll(Iterable<E> iterable);
 
   /// An [Iterable] of the objects in this list in reverse order.
+  /// ```dart
+  /// final numbers = <String>['two', 'three', 'four'];
+  /// final reverseOrder = numbers.reversed;
+  /// print(reverseOrder.toList()); // [four, three, two]
+  /// ```
   Iterable<E> get reversed;
 
   /// Sorts this list according to the order specified by the [compare] function.
   ///
   /// The [compare] function must act as a [Comparator].
   /// ```dart
-  /// var numbers = ['two', 'three', 'four'];
+  /// final numbers = <String>['two', 'three', 'four'];
   /// // Sort from shortest to longest.
   /// numbers.sort((a, b) => a.length.compareTo(b.length));
-  /// print(numbers);  // [two, four, three]
+  /// print(numbers); // [two, four, three]
   /// ```
   /// The default [List] implementations use [Comparable.compare] if
   /// [compare] is omitted.
   /// ```dart
-  /// List<int> nums = [13, 2, -11];
-  /// nums.sort();
-  /// print(nums);  // [-11, 2, 13]
+  /// final numbers = <int>[13, 2, -11, 0];
+  /// numbers.sort();
+  /// print(numbers); // [-11, 0, 2, 13]
   /// ```
   /// In that case, the elements of the list must be [Comparable] to
   /// each other.
@@ -356,13 +510,18 @@
   /// The sort function is not guaranteed to be stable, so distinct objects
   /// that compare as equal may occur in any order in the result:
   /// ```dart
-  /// var numbers = ['one', 'two', 'three', 'four'];
+  /// final numbers = <String>['one', 'two', 'three', 'four'];
   /// numbers.sort((a, b) => a.length.compareTo(b.length));
-  /// print(numbers);  // [one, two, four, three] OR [two, one, four, three]
+  /// print(numbers); // [one, two, four, three] OR [two, one, four, three]
   /// ```
   void sort([int compare(E a, E b)?]);
 
   /// Shuffles the elements of this list randomly.
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3, 4, 5];
+  /// numbers.shuffle();
+  /// print(numbers); // [1, 3, 4, 5, 2] OR some other random result.
+  /// ```
   void shuffle([Random? random]);
 
   /// The first index of [element] in this list.
@@ -371,13 +530,15 @@
   /// The first time an object `o` is encountered so that `o == element`,
   /// the index of `o` is returned.
   /// ```dart
-  /// var notes = ['do', 're', 'mi', 're'];
-  /// notes.indexOf('re');    // 1
-  /// notes.indexOf('re', 2); // 3
+  /// final notes = <String>['do', 're', 'mi', 're'];
+  /// print(notes.indexOf('re')); // 1
+  ///
+  /// final indexWithStart = notes.indexOf('re', 2); // 3
   /// ```
   /// Returns -1 if [element] is not found.
   /// ```dart
-  /// notes.indexOf('fa');    // -1
+  /// final notes = <String>['do', 're', 'mi', 're'];
+  /// final index = notes.indexOf('fa'); // -1
   /// ```
   int indexOf(E element, [int start = 0]);
 
@@ -388,14 +549,15 @@
   /// the index of `o` is returned.
   ///
   /// ```dart
-  /// var notes = ['do', 're', 'mi', 're'];
-  /// notes.indexWhere((note) => note.startsWith('r'));       // 1
-  /// notes.indexWhere((note) => note.startsWith('r'), 2);    // 3
+  /// final notes = <String>['do', 're', 'mi', 're'];
+  /// final first = notes.indexWhere((note) => note.startsWith('r')); // 1
+  /// final second = notes.indexWhere((note) => note.startsWith('r'), 2); // 3
   /// ```
   ///
   /// Returns -1 if [element] is not found.
   /// ```dart
-  /// notes.indexWhere((note) => note.startsWith('k'));    // -1
+  /// final notes = <String>['do', 're', 'mi', 're'];
+  /// final index = notes.indexWhere((note) => note.startsWith('k')); // -1
   /// ```
   int indexWhere(bool test(E element), [int start = 0]);
 
@@ -407,14 +569,17 @@
   /// If [start] is omitted, it defaults to the [length] of the list.
   ///
   /// ```dart
-  /// var notes = ['do', 're', 'mi', 're'];
-  /// notes.lastIndexWhere((note) => note.startsWith('r'));       // 3
-  /// notes.lastIndexWhere((note) => note.startsWith('r'), 2);    // 1
+  /// final notes = <String>['do', 're', 'mi', 're'];
+  /// final first = notes.lastIndexWhere((note) => note.startsWith('r')); // 3
+  /// final second = notes.lastIndexWhere((note) => note.startsWith('r'),
+  ///     2); // 1
   /// ```
   ///
   /// Returns -1 if [element] is not found.
   /// ```dart
-  /// notes.lastIndexWhere((note) => note.startsWith('k'));    // -1
+  /// final notes = <String>['do', 're', 'mi', 're'];
+  /// final index = notes.lastIndexWhere((note) => note.startsWith('k'));
+  /// print(index); // -1
   /// ```
   int lastIndexWhere(bool test(E element), [int? start]);
 
@@ -425,23 +590,33 @@
   /// The first time an object `o` is encountered so that `o == element`,
   /// the index of `o` is returned.
   /// ```dart
-  /// var notes = ['do', 're', 'mi', 're'];
-  /// notes.lastIndexOf('re', 2); // 1
+  /// final notes = <String>['do', 're', 'mi', 're'];
+  /// const startIndex = 2;
+  /// final index = notes.lastIndexOf('re', startIndex); // 1
   /// ```
   /// If [start] is not provided, this method searches from the end of the
   /// list.
   /// ```dart
-  /// notes.lastIndexOf('re');  // 3
+  /// final notes = <String>['do', 're', 'mi', 're'];
+  /// final index = notes.lastIndexOf('re'); // 3
   /// ```
   /// Returns -1 if [element] is not found.
   /// ```dart
-  /// notes.lastIndexOf('fa');  // -1
+  /// final notes = <String>['do', 're', 'mi', 're'];
+  /// final index = notes.lastIndexOf('fa'); // -1
   /// ```
   int lastIndexOf(E element, [int? start]);
 
   /// Removes all objects from this list; the length of the list becomes zero.
   ///
   /// The list must be growable.
+  ///
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3];
+  /// numbers.clear();
+  /// print(numbers.length); // 0
+  /// print(numbers); // []
+  /// ```
   void clear();
 
   /// Inserts [element] at position [index] in this list.
@@ -451,6 +626,13 @@
   ///
   /// The list must be growable.
   /// The [index] value must be non-negative and no greater than [length].
+  ///
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3, 4];
+  /// const index = 2;
+  /// numbers.insert(index, 10);
+  /// print(numbers); // [1, 2, 10, 3, 4]
+  /// ```
   void insert(int index, E element);
 
   /// Inserts all objects of [iterable] at position [index] in this list.
@@ -460,17 +642,18 @@
   ///
   /// The list must be growable.
   /// The [index] value must be non-negative and no greater than [length].
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3, 4];
+  /// final insertItems = [10, 11];
+  /// numbers.insertAll(2, insertItems);
+  /// print(numbers); // [1, 2, 10, 11, 3, 4]
+  /// ```
   void insertAll(int index, Iterable<E> iterable);
 
   /// Overwrites elements with the objects of [iterable].
   ///
   /// The elements of [iterable] are written into this list,
   /// starting at position [index].
-  /// ```dart
-  /// var list = ['a', 'b', 'c', 'd'];
-  /// list.setAll(1, ['bee', 'sea']);
-  /// list.join(', '); // 'a, bee, sea, d'
-  /// ```
   /// This operation does not increase the length of the list.
   ///
   /// The [index] must be non-negative and no greater than [length].
@@ -480,24 +663,30 @@
   ///
   /// If `iterable` is based on this list, its values may change _during_ the
   /// `setAll` operation.
+  /// ```dart
+  /// final list = <String>['a', 'b', 'c', 'd'];
+  /// list.setAll(1, ['bee', 'sea']);
+  /// print(list); // [a, bee, sea, d]
+  /// ```
   void setAll(int index, Iterable<E> iterable);
 
   /// Removes the first occurrence of [value] from this list.
   ///
   /// Returns true if [value] was in the list, false otherwise.
+  /// The list must be growable.
+  ///
   /// ```dart
-  /// var parts = ['head', 'shoulders', 'knees', 'toes'];
-  /// parts.remove('head'); // true
-  /// parts.join(', ');     // 'shoulders, knees, toes'
+  /// final parts = <String>['head', 'shoulders', 'knees', 'toes'];
+  /// final retVal = parts.remove('head'); // true
+  /// print(parts); // [shoulders, knees, toes]
   /// ```
   /// The method has no effect if [value] was not in the list.
   /// ```dart
+  /// final parts = <String>['shoulders', 'knees', 'toes'];
   /// // Note: 'head' has already been removed.
-  /// parts.remove('head'); // false
-  /// parts.join(', ');     // 'shoulders, knees, toes'
+  /// final retVal = parts.remove('head'); // false
+  /// print(parts); // [shoulders, knees, toes]
   /// ```
-  ///
-  /// The list must be growable.
   bool remove(Object? value);
 
   /// Removes the object at position [index] from this list.
@@ -508,22 +697,31 @@
   /// Returns the removed value.
   ///
   /// The [index] must be in the range `0 ≤ index < length`.
-  ///
   /// The list must be growable.
+  /// ```dart
+  /// final parts = <String>['head', 'shoulder', 'knees', 'toes'];
+  /// final retVal = parts.removeAt(2); // knees
+  /// print(parts); // [head, shoulder, toes]
+  /// ```
   E removeAt(int index);
 
   /// Removes and returns the last object in this list.
   ///
   /// The list must be growable and non-empty.
+  /// ```dart
+  /// final parts = <String>['head', 'shoulder', 'knees', 'toes'];
+  /// final retVal = parts.removeLast(); // toes
+  /// print(parts); // [head, shoulder, knees]
+  /// ```
   E removeLast();
 
   /// Removes all objects from this list that satisfy [test].
   ///
   /// An object `o` satisfies [test] if `test(o)` is true.
   /// ```dart
-  /// var numbers = ['one', 'two', 'three', 'four'];
+  /// final numbers = <String>['one', 'two', 'three', 'four'];
   /// numbers.removeWhere((item) => item.length == 3);
-  /// numbers.join(', '); // 'three, four'
+  /// print(numbers); // [three, four]
   /// ```
   /// The list must be growable.
   void removeWhere(bool test(E element));
@@ -532,9 +730,9 @@
   ///
   /// An object `o` satisfies [test] if `test(o)` is true.
   /// ```dart
-  /// var numbers = ['one', 'two', 'three', 'four'];
+  /// final numbers = <String>['one', 'two', 'three', 'four'];
   /// numbers.retainWhere((item) => item.length == 3);
-  /// numbers.join(', '); // 'one, two'
+  /// print(numbers); // [one, two]
   /// ```
   /// The list must be growable.
   void retainWhere(bool test(E element));
@@ -556,18 +754,19 @@
   /// order as they occur in this list.
   ///
   /// ```dart
-  /// var colors = ["red", "green", "blue", "orange", "pink"];
+  /// final colors = <String>['red', 'green', 'blue', 'orange', 'pink'];
   /// print(colors.sublist(1, 3)); // [green, blue]
   /// ```
   ///
   /// If [end] is omitted, it defaults to the [length] of this list.
   ///
   /// ```dart
-  /// print(colors.sublist(1)); // [green, blue, orange, pink]
+  /// final colors = <String>['red', 'green', 'blue', 'orange', 'pink'];
+  /// print(colors.sublist(3)); // [orange, pink]
   /// ```
   ///
   /// The `start` and `end` positions must satisfy the relations
-  /// 0 ≤ `start` ≤ `end` ≤ [length]
+  /// 0 ≤ `start` ≤ `end` ≤ [length].
   /// If `end` is equal to `start`, then the returned list is empty.
   List<E> sublist(int start, [int? end]);
 
@@ -586,11 +785,12 @@
   /// ends early if it reaches the end of the list early
   /// (if `end`, or even `start`, becomes greater than [length]).
   /// ```dart
-  /// List<String> colors = ['red', 'green', 'blue', 'orange', 'pink'];
-  /// Iterable<String> range = colors.getRange(1, 4);
-  /// range.join(', ');  // 'green, blue, orange'
-  /// colors.length = 3;
-  /// range.join(', ');  // 'green, blue'
+  /// final colors = <String>['red', 'green', 'blue', 'orange', 'pink'];
+  /// final firstRange = colors.getRange(0, 3);
+  /// print(firstRange.join(', ')); // red, green, blue
+  ///
+  /// final secondRange = colors.getRange(2, 5);
+  /// print(secondRange.join(', ')); // blue, orange, pink
   /// ```
   Iterable<E> getRange(int start, int end);
 
@@ -599,12 +799,13 @@
   /// Copies the objects of [iterable], skipping [skipCount] objects first,
   /// into the range from [start], inclusive, to [end], exclusive, of this list.
   /// ```dart
-  /// var list1 = [1, 2, 3, 4];
-  /// var list2 = [5, 6, 7, 8, 9];
+  /// final list1 = <int>[1, 2, 3, 4];
+  /// final list2 = <int>[5, 6, 7, 8, 9];
   /// // Copies the 4th and 5th items in list2 as the 2nd and 3rd items
   /// // of list1.
-  /// list1.setRange(1, 3, list2, 3);
-  /// list1.join(', '); // '1, 8, 9, 4'
+  /// const skipCount = 3;
+  /// list1.setRange(1, 3, list2, skipCount);
+  /// print(list1); // [1, 8, 9, 4]
   /// ```
   /// The provided range, given by [start] and [end], must be valid.
   /// A range from [start] to [end] is valid if 0 ≤ `start` ≤ `end` ≤ [length].
@@ -632,6 +833,11 @@
   /// An empty range (with `end == start`) is valid.
   ///
   /// The list must be growable.
+  /// ```dart
+  /// final numbers = <int>[1, 2, 3, 4, 5];
+  /// numbers.removeRange(1, 4);
+  /// print(numbers); // [1, 5]
+  /// ```
   void removeRange(int start, int end);
 
   /// Overwrites a range of elements with [fillValue].
@@ -643,16 +849,16 @@
   /// A range from [start] to [end] is valid if 0 ≤ `start` ≤ `end` ≤ [length].
   /// An empty range (with `end == start`) is valid.
   ///
-  /// Example:
-  /// ```dart
-  /// var list = List.filled(5, -1);
-  /// print(list); //  [-1, -1, -1, -1, -1]
-  /// list.fillRange(1, 3, 4);
-  /// print(list); //  [-1, 4, 4, -1, -1]
-  /// ```
-  ///
   /// If the element type is not nullable, the [fillValue] must be provided and
   /// must be non-`null`.
+  ///
+  /// Example:
+  /// ```dart
+  /// final words = List.filled(5, 'old');
+  /// print(words); // [old, old, old, old, old]
+  /// words.fillRange(1, 3, 'new');
+  /// print(words); // [old, new, new, old, old]
+  /// ```
   void fillRange(int start, int end, [E? fillValue]);
 
   /// Replaces a range of elements with the elements of [replacements].
@@ -660,9 +866,10 @@
   /// Removes the objects in the range from [start] to [end],
   /// then inserts the elements of [replacements] at [start].
   /// ```dart
-  /// var list = [1, 2, 3, 4, 5];
-  /// list.replaceRange(1, 4, [6, 7]);
-  /// list.join(', '); // '1, 6, 7, 5'
+  /// final numbers = <int>[1, 2, 3, 4, 5];
+  /// final replacements = [6, 7];
+  /// numbers.replaceRange(1, 4, replacements);
+  /// print(numbers); // [1, 6, 7, 5]
   /// ```
   /// The provided range, given by [start] and [end], must be valid.
   /// A range from [start] to [end] is valid if 0 ≤ `start` ≤ `end` ≤ [length].
@@ -671,8 +878,11 @@
   /// The operation `list.replaceRange(start, end, replacements)`
   /// is roughly equivalent to:
   /// ```dart
-  /// list.removeRange(start, end);
-  /// list.insertAll(start, replacements);
+  /// final numbers = <int>[1, 2, 3, 4, 5];
+  /// numbers.removeRange(1, 4);
+  /// final replacements = [6, 7];
+  /// numbers.insertAll(1, replacements);
+  /// print(numbers); // [1, 6, 7, 5]
   /// ```
   /// but may be more efficient.
   ///
@@ -688,7 +898,7 @@
   /// as values. The `Map.keys` [Iterable] iterates the indices of this list
   /// in numerical order.
   /// ```dart
-  /// var words = ['fee', 'fi', 'fo', 'fum'];
+  /// var words = <String>['fee', 'fi', 'fo', 'fum'];
   /// var map = words.asMap();  // {0: fee, 1: fi, 2: fo, 3: fum}
   /// map.keys.toList(); // [0, 1, 2, 3]
   /// ```
diff --git a/sdk/lib/core/map.dart b/sdk/lib/core/map.dart
index 164b6f2..f6c6caf 100644
--- a/sdk/lib/core/map.dart
+++ b/sdk/lib/core/map.dart
@@ -51,6 +51,11 @@
   /// A `LinkedHashMap` requires the keys to implement compatible
   /// `operator==` and `hashCode`.
   /// It iterates in key insertion order.
+  /// ```dart
+  /// final planets = <num, String>{1: 'Mercury', 2: 'Venus', 3: 'Earth', 4: 'Mars'};
+  /// final mapFrom = Map<int, String>.from(planets);
+  /// print(mapFrom); // {1: Mercury, 2: Venus, 3: Earth, 4: Mars}
+  /// ```
   factory Map.from(Map other) = LinkedHashMap<K, V>.from;
 
   /// Creates a [LinkedHashMap] with the same keys and values as [other].
@@ -58,6 +63,11 @@
   /// A `LinkedHashMap` requires the keys to implement compatible
   /// `operator==` and `hashCode`, and it allows `null` as a key.
   /// It iterates in key insertion order.
+  /// ```dart
+  /// final planets = <int, String>{1: 'Mercury', 2: 'Venus', 3: 'Earth'};
+  /// final mapOf = Map<num, String>.of(planets);
+  /// print(mapOf); // {1: Mercury, 2: Venus, 3: Earth}
+  /// ```
   factory Map.of(Map<K, V> other) = LinkedHashMap<K, V>.of;
 
   /// Creates an unmodifiable hash-based map containing the entries of [other].
@@ -72,6 +82,11 @@
   ///
   /// The resulting map behaves like the result of [Map.from],
   /// except that the map returned by this constructor is not modifiable.
+  /// ```dart
+  /// final planets = <int, String>{1: 'Mercury', 2: 'Venus', 3: 'Earth'};
+  /// final unmodifiableMap = Map.unmodifiable(planets);
+  /// unmodifiableMap[4] = 'Mars'; // Throws
+  /// ```
   external factory Map.unmodifiable(Map<dynamic, dynamic> other);
 
   /// Creates an identity map with the default implementation, [LinkedHashMap].
@@ -100,11 +115,11 @@
   /// The keys of `map` are the `list` values converted to strings,
   /// and the values of the `map` are the squares of the `list` values:
   /// ```dart
-  /// List<int> list = [1, 2, 3];
-  /// var map = Map<String, int>.fromIterable(list,
+  /// final numbers = <int>[1, 2, 3];
+  /// final map = Map<String, int>.fromIterable(numbers,
   ///     key: (item) => item.toString(),
   ///     value: (item) => item * item);
-  /// // map is {"1": 1, "2": 4, "3": 9}
+  /// print(map); // {1: 1, 2: 4, 3: 9}
   /// ```
   /// If no values are specified for [key] and [value],
   /// the default is the identity function.
@@ -114,8 +129,9 @@
   /// In the following example, the keys and corresponding values of `map`
   /// are the `list` values directly:
   /// ```dart
-  /// var map = Map<int, int>.fromIterable(list);
-  /// // map is {1: 1, 2: 2, 3: 3}
+  /// final numbers = <int>[1, 2, 3];
+  /// final map = Map.fromIterable(numbers);
+  /// print(map); // {1: 1, 2: 2, 3: 3}
   /// ```
   /// The keys computed by the source [iterable] do not need to be unique.
   /// The last occurrence of a key will overwrite
@@ -134,10 +150,10 @@
   /// The map construction iterates over [keys] and [values] simultaneously,
   /// and adds an entry to the map for each pair of key and value.
   /// ```dart
-  /// List<String> letters = ['b', 'c'];
-  /// List<String> words = ['bad', 'cat'];
-  /// var map = Map.fromIterables(letters, words);
-  /// // map is {"b": "bad", "c": "cat"}
+  /// final rings = <bool>[false, false, true, true];
+  /// final planets = <String>{'Earth', 'Mars', 'Jupiter', 'Saturn'};
+  /// final map = Map<String, bool>.fromIterables(planets, rings);
+  /// print(map); // {Earth: false, Mars: false, Jupiter: true, Saturn: true}
   /// ```
   /// If [keys] contains the same object multiple times,
   /// the value of the last occurrence overwrites any previous value.
@@ -183,6 +199,12 @@
   /// ```dart
   /// <K, V>{for (var e in entries) e.key: e.value}
   /// ```
+  /// Example:
+  /// ```dart
+  /// final moonCount = <String, int>{'Mercury': 0, 'Venus': 0, 'Earth': 1,
+  ///   'Mars': 2, 'Jupiter': 79, 'Saturn': 82, 'Uranus': 27, 'Neptune': 14};
+  /// final map = Map.fromEntries(moonCount.entries);
+  /// ```
   factory Map.fromEntries(Iterable<MapEntry<K, V>> entries) =>
       <K, V>{}..addEntries(entries);
 
@@ -211,12 +233,24 @@
   ///
   /// Returns true if any of the values in the map are equal to `value`
   /// according to the `==` operator.
+  /// ```dart
+  /// final moonCount = <String, int>{'Mercury': 0, 'Venus': 0, 'Earth': 1,
+  ///   'Mars': 2, 'Jupiter': 79, 'Saturn': 82, 'Uranus': 27, 'Neptune': 14 };
+  /// final moons3 = moonCount.containsValue(3); // false
+  /// final moons82 = moonCount.containsValue(82); // true
+  /// ```
   bool containsValue(Object? value);
 
   /// Whether this map contains the given [key].
   ///
   /// Returns true if any of the keys in the map are equal to `key`
   /// according to the equality used by the map.
+  /// ```dart
+  /// final moonCount = <String, int>{'Mercury': 0, 'Venus': 0, 'Earth': 1,
+  ///   'Mars': 2, 'Jupiter': 79, 'Saturn': 82, 'Uranus': 27, 'Neptune': 14 };
+  /// final containsUranus = moonCount.containsKey('Uranus'); // true
+  /// final containsPluto = moonCount.containsKey('Pluto'); // false
+  /// ```
   bool containsKey(Object? key);
 
   /// The value for the given [key], or `null` if [key] is not in the map.
@@ -248,6 +282,17 @@
   ///
   /// The operation is equivalent to doing `this[entry.key] = entry.value`
   /// for each [MapEntry] of the iterable.
+  /// ```dart
+  /// final planets = <int, String>{1: 'Mercury', 2: 'Venus',
+  ///   3: 'Earth', 4: 'Mars'};
+  /// final gasGiants = <int, String>{5: 'Jupiter', 6: 'Saturn'};
+  /// final iceGiants = <int, String>{7: 'Uranus', 8: 'Neptune'};
+  /// planets.addEntries(gasGiants.entries);
+  /// planets.addEntries(iceGiants.entries);
+  /// print(planets);
+  /// // {1: Mercury, 2: Venus, 3: Earth, 4: Mars, 5: Jupiter, 6: Saturn,
+  /// //  7: Uranus, 8: Neptune}
+  /// ```
   void addEntries(Iterable<MapEntry<K, V>> newEntries);
 
   /// Updates the value for the provided [key].
@@ -261,15 +306,38 @@
   /// and adds the key with the returned value to the map.
   ///
   /// If the key is not present, [ifAbsent] must be provided.
+  /// ```dart
+  /// final planetsFromSun = <int, String>{1: 'Mercury', 2: 'unknown',
+  ///   3: 'Earth'};
+  /// // Update value for known key value 2.
+  /// planetsFromSun.update(2, (value) => 'Venus');
+  /// print(planetsFromSun); // {1: Mercury, 2: Venus, 3: Earth}
+  ///
+  /// final largestPlanets = <int, String>{1: 'Jupiter', 2: 'Saturn',
+  ///   3: 'Neptune'};
+  /// // Key value 8 is missing from list, add it using [ifAbsent].
+  /// largestPlanets.update(8, (value) => 'New', ifAbsent: () => 'Mercury');
+  /// print(largestPlanets); // {1: Jupiter, 2: Saturn, 3: Neptune, 8: Mercury}
+  /// ```
   V update(K key, V update(V value), {V ifAbsent()?});
 
   /// Updates all values.
   ///
   /// Iterates over all entries in the map and updates them with the result
   /// of invoking [update].
+  /// ```dart
+  /// final terrestrial = <int, String>{1: 'Mercury', 2: 'Venus', 3: 'Earth'};
+  /// terrestrial.updateAll((key, value) => value.toUpperCase());
+  /// print(terrestrial); // {1: MERCURY, 2: VENUS, 3: EARTH}
+  /// ```
   void updateAll(V update(K key, V value));
 
   /// Removes all entries of this map that satisfy the given [test].
+  /// ```dart
+  /// final terrestrial = <int, String>{1: 'Mercury', 2: 'Venus', 3: 'Earth'};
+  /// terrestrial.removeWhere((key, value) => value.startsWith('E'));
+  /// print(terrestrial); // {1: Mercury, 2: Venus}
+  /// ```
   void removeWhere(bool test(K key, V value));
 
   /// Look up the value of [key], or add a new entry if it isn't there.
@@ -278,13 +346,18 @@
   /// Otherwise calls [ifAbsent] to get a new value, associates [key] to
   /// that value, and then returns the new value.
   /// ```dart
-  /// Map<String, int> scores = {'Bob': 36};
-  /// for (var key in ['Bob', 'Rohan', 'Sophena']) {
-  ///   scores.putIfAbsent(key, () => key.length);
+  /// final diameters = <num, String>{1.0: 'Earth'};
+  /// final otherDiameters = <double, String>{0.383: 'Mercury', 0.949: 'Venus'};
+  ///
+  /// for (final item in otherDiameters.entries) {
+  ///   diameters.putIfAbsent(item.key, () => item.value);
   /// }
-  /// scores['Bob'];      // 36
-  /// scores['Rohan'];    //  5
-  /// scores['Sophena'];  //  7
+  /// print(diameters); // {1.0: Earth, 0.383: Mercury, 0.949: Venus}
+  ///
+  /// // If the key already exists, the current value is returned.
+  /// final result = diameters.putIfAbsent(0.383, () => 'Random');
+  /// print(result); // Mercury
+  /// print(diameters); // {1.0: Earth, 0.383: Mercury, 0.949: Venus}
   /// ```
   /// Calling [ifAbsent] must not add or remove keys from the map.
   V putIfAbsent(K key, V ifAbsent());
@@ -296,6 +369,11 @@
   /// The operation is equivalent to doing `this[key] = value` for each key
   /// and associated value in other. It iterates over [other], which must
   /// therefore not change during the iteration.
+  /// ```dart
+  /// final planets = <int, String>{1: 'Mercury', 2: 'Earth'};
+  /// planets.addAll({5: 'Jupiter', 6: 'Saturn'});
+  /// print(planets); // {1: Mercury, 2: Earth, 5: Jupiter, 6: Saturn}
+  /// ```
   void addAll(Map<K, V> other);
 
   /// Removes [key] and its associated value, if present, from the map.
@@ -305,16 +383,37 @@
   ///
   /// Note that some maps allow `null` as a value,
   /// so a returned `null` value doesn't always mean that the key was absent.
+  /// ```dart
+  /// final terrestrial = <int, String>{1: 'Mercury', 2: 'Venus', 3: 'Earth'};
+  /// final removedValue = terrestrial.remove(2); // Venus
+  /// print(terrestrial); // {1: Mercury, 3: Earth}
+  /// ```
   V? remove(Object? key);
 
   /// Removes all entries from the map.
   ///
   /// After this, the map is empty.
+  /// ```dart
+  /// final planets = <int, String>{1: 'Mercury', 2: 'Venus', 3: 'Earth'};
+  /// planets.clear(); // {}
+  /// ```
   void clear();
 
   /// Applies [action] to each key/value pair of the map.
   ///
   /// Calling `action` must not add or remove keys from the map.
+  /// ```dart
+  /// final planetsByMass = <num, String>{0.81: 'Venus', 1: 'Earth',
+  ///   0.11: 'Mars', 17.15: 'Neptune'};
+  ///
+  /// planetsByMass.forEach((key, value) {
+  ///   print('$key: $value');
+  ///   // 0.81: Venus
+  ///   // 1: Earth
+  ///   // 0.11: Mars
+  ///   // 17.15: Neptune
+  /// });
+  /// ```
   void forEach(void action(K key, V value));
 
   /// The keys of [this].
diff --git a/sdk/lib/core/num.dart b/sdk/lib/core/num.dart
index eab5eb9..4da3b29 100644
--- a/sdk/lib/core/num.dart
+++ b/sdk/lib/core/num.dart
@@ -8,6 +8,13 @@
 ///
 /// It is a compile-time error for any type other than [int] or [double]
 /// to attempt to extend or implement `num`.
+///
+/// **See also:**
+/// * [int]: An integer number.
+/// * [double]: A double-precision floating point number.
+/// * [Numbers](https://dart.dev/guides/language/numbers) in
+/// [A tour of the Dart language](https://dart.dev/guides/language/language-tour).
+
 abstract class num implements Comparable<num> {
   /// Test whether this value is numerically equal to `other`.
   ///
@@ -65,7 +72,7 @@
   /// NaN return false.
   ///
   /// This function imposes a complete ordering for doubles. When using
-  /// `compareTo` the following properties hold:
+  /// `compareTo`, the following properties hold:
   ///
   /// - All NaN values are considered equal, and greater than any numeric value.
   /// - -0.0 is less than 0.0 (and the integer 0), but greater than any non-zero
@@ -113,7 +120,7 @@
   /// Multiplies this number by [other].
   ///
   /// The result is an [int], as described by [int.*],
-  /// if both this number and [other] is an integer,
+  /// if both this number and [other] are integers,
   /// otherwise the result is a [double].
   num operator *(num other);
 
@@ -125,7 +132,7 @@
   /// `a == b * q + r` and `0 <= r < b.abs()`.
   ///
   /// The Euclidean division is only defined for integers, but can be easily
-  /// extended to work with doubles. In that case `q` is stil an integer,
+  /// extended to work with doubles. In that case, `q` is still an integer,
   /// but `r` may have a non-integer value that still satisfies `0 <= r < |b|`.
   ///
   /// The sign of the returned value `r` is always positive.
@@ -133,9 +140,17 @@
   /// See [remainder] for the remainder of the truncating division.
   ///
   /// The result is an [int], as described by [int.%],
-  /// if both this number and [other] is an integer,
+  /// if both this number and [other] are integers,
   /// otherwise the result is a [double].
-  num operator %(num other);
+  ///
+  /// Example:
+  /// ```dart
+  /// print(5 % 3); // 2
+  /// print(-5 % 3); // 1
+  /// print(5 % -3); // 2
+  /// print(-5 % -3); // 1
+  /// ```
+ num operator %(num other);
 
   /// Divides this number by [other].
   double operator /(num other);
@@ -146,11 +161,11 @@
   /// Truncating division is division where a fractional result
   /// is converted to an integer by rounding towards zero.
   ///
-  /// If both operands are [int]s then [other] must not be zero.
+  /// If both operands are [int]s, then [other] must not be zero.
   /// Then `a ~/ b` corresponds to `a.remainder(b)`
   /// such that `a == (a ~/ b) * b + a.remainder(b)`.
   ///
-  /// If either operand is a [double] then the other operand is converted
+  /// If either operand is a [double], then the other operand is converted
   /// to a double before performing the division and truncation of the result.
   /// Then `a ~/ b` is equivalent to `(a / b).truncate()`.
   /// This means that the intermediate result of the double division
@@ -164,7 +179,7 @@
   /// numbers numerical value (the result of subtracting the
   /// number from zero), if that value *exists*.
   ///
-  /// Negating a double gives a number with same magnitude
+  /// Negating a double gives a number with the same magnitude
   /// as the original value (`number.abs() == (-number).abs()`),
   /// and the opposite sign (`-(number.sign) == (-number).sign`).
   ///
@@ -179,11 +194,20 @@
   ///
   /// The result `r` of this operation satisfies:
   /// `this == (this ~/ other) * other + r`.
-  /// As a consequence the remainder `r` has the same sign as the divider `this`.
+  /// As a consequence, the remainder `r` has the same sign as the divider
+  /// `this`.
   ///
   /// The result is an [int], as described by [int.remainder],
-  /// if both this number and [other] is an integer,
+  /// if both this number and [other] are integers,
   /// otherwise the result is a [double].
+  ///
+  /// Example:
+  /// ```dart
+  /// print(5.remainder(3)); // 2
+  /// print(-5.remainder(3)); // -2
+  /// print(5.remainder(-3)); // 2
+  /// print(-5.remainder(-3)); // -2
+  /// ```
   num remainder(num other);
 
   /// Whether this number is numerically smaller than [other].
@@ -256,6 +280,11 @@
   /// and `-value` if the value is negative.
   ///
   /// Integer overflow may cause the result of `-value` to stay negative.
+  ///
+  /// ```dart
+  /// print((2).abs()); // 2
+  /// print((-2.5).abs()); // 2.5
+  /// ```
   num abs();
 
   /// Negative one, zero or positive one depending on the sign and
@@ -336,7 +365,7 @@
   ///
   /// For the purpose of rounding, `-0.0` is considered to be below `0.0`,
   /// and `-0.0` is therefore considered closer to negative numbers than `0.0`.
-  /// This means that for a value, `d` in the range `-0.5 < d < 0.0`,
+  /// This means that for a value `d` in the range `-0.5 < d < 0.0`,
   /// the result is `-0.0`.
   double roundToDouble();
 
@@ -377,6 +406,14 @@
   ///
   /// The arguments [lowerLimit] and [upperLimit] must form a valid range where
   /// `lowerLimit.compareTo(upperLimit) <= 0`.
+  ///
+  /// Example:
+  /// ```dart
+  /// var result = 10.5.clamp(5, 10.0); // 10.0
+  /// result = 0.75.clamp(5, 10.0); // 5
+  /// result = (-10).clamp(-5, 5.0); // -5
+  /// result = (-0.0).clamp(-5, 5.0); // -0.0
+  /// ```
   num clamp(num lowerLimit, num upperLimit);
 
   /// Truncates this [num] to an integer and returns the result as an [int].
@@ -396,11 +433,11 @@
   /// before computing the string representation,
   /// as by [toDouble].
   ///
-  /// If the absolute value of `this` is greater then or equal to `10^21` then
+  /// If the absolute value of `this` is greater than or equal to `10^21`, then
   /// this methods returns an exponential representation computed by
   /// `this.toStringAsExponential()`. Otherwise the result
   /// is the closest string representation with exactly [fractionDigits] digits
-  /// after the decimal point. If [fractionDigits] equals 0 then the decimal
+  /// after the decimal point. If [fractionDigits] equals 0, then the decimal
   /// point is omitted.
   ///
   /// The parameter [fractionDigits] must be an integer satisfying:
@@ -422,13 +459,13 @@
   /// Converts this number to a [double]
   /// before computing the string representation.
   ///
-  /// If [fractionDigits] is given then it must be an integer satisfying:
+  /// If [fractionDigits] is given, then it must be an integer satisfying:
   /// `0 <= fractionDigits <= 20`. In this case the string contains exactly
   /// [fractionDigits] after the decimal point. Otherwise, without the parameter,
   /// the returned string uses the shortest number of digits that accurately
   /// represent this number.
   ///
-  /// If [fractionDigits] equals 0 then the decimal point is omitted.
+  /// If [fractionDigits] equals 0, then the decimal point is omitted.
   /// Examples:
   /// ```dart
   /// 1.toStringAsExponential();       // 1e+0
@@ -461,7 +498,7 @@
   /// ```
   String toStringAsPrecision(int precision);
 
-  /// The shortest string that correctly represent this number number.
+  /// The shortest string that correctly represents this number.
   ///
   /// All [double]s in the range `10^-6` (inclusive) to `10^21` (exclusive)
   /// are converted to their decimal representation with at least one digit
@@ -517,6 +554,22 @@
   /// The [onError] parameter is deprecated and will be removed.
   /// Instead of `num.parse(string, (string) { ... })`,
   /// you should use `num.tryParse(string) ?? (...)`.
+  ///
+  /// Examples:
+  /// ```dart
+  /// var value = num.parse('2021'); // 2021
+  /// value = num.parse('3.14'); // 3.14
+  /// value = num.parse('  3.14 \xA0'); // 3.14
+  /// value = num.parse('0.'); // 0.0
+  /// value = num.parse('.0'); // 0.0
+  /// value = num.parse('-1.e3'); // -1000.0
+  /// value = num.parse('1234E+7'); // 12340000000.0
+  /// value = num.parse('+.12e-9'); // 1.2e-10
+  /// value = num.parse('-NaN'); // NaN
+  /// value = num.parse('0xFF'); // 255
+  /// value = num.parse(double.infinity.toString()); // Infinity
+  /// value = num.parse('1f'); // Throws.
+  /// ```
   static num parse(String input, [@deprecated num onError(String input)?]) {
     num? result = tryParse(input);
     if (result != null) return result;
@@ -526,8 +579,24 @@
 
   /// Parses a string containing a number literal into a number.
   ///
-  /// Like [parse] except that this function returns `null` for invalid inputs
+  /// Like [parse], except that this function returns `null` for invalid inputs
   /// instead of throwing.
+  ///
+  /// Examples:
+  /// ```dart
+  /// var value = num.tryParse('2021'); // 2021
+  /// value = num.tryParse('3.14'); // 3.14
+  /// value = num.tryParse('  3.14 \xA0'); // 3.14
+  /// value = num.tryParse('0.'); // 0.0
+  /// value = num.tryParse('.0'); // 0.0
+  /// value = num.tryParse('-1.e3'); // -1000.0
+  /// value = num.tryParse('1234E+7'); // 12340000000.0
+  /// value = num.tryParse('+.12e-9'); // 1.2e-10
+  /// value = num.tryParse('-NaN'); // NaN
+  /// value = num.tryParse('0xFF'); // 255
+  /// value = num.tryParse(double.infinity.toString()); // Infinity
+  /// value = num.tryParse('1f'); // null
+  /// ```
   static num? tryParse(String input) {
     String source = input.trim();
     // TODO(lrn): Optimize to detect format and result type in one check.
diff --git a/sdk/lib/core/string.dart b/sdk/lib/core/string.dart
index ca31986..8764498 100644
--- a/sdk/lib/core/string.dart
+++ b/sdk/lib/core/string.dart
@@ -8,7 +8,7 @@
 ///
 /// Strings are mainly used to represent text. A character may be represented by
 /// multiple code points, each code point consisting of one or two code
-/// units. For example the Papua New Guinea flag character requires four code
+/// units. For example, the Papua New Guinea flag character requires four code
 /// units to represent two code points, but should be treated like a single
 /// character: "🇵🇬". Platforms that do not support the flag character may show
 /// the letters "PG" instead. If the code points are swapped, it instead becomes
@@ -35,41 +35,49 @@
 /// Strings are immutable. Although you cannot change a string, you can perform
 /// an operation on a string which creates a new string:
 /// ```dart
-/// var string = 'Dart is fun';
-/// var newString = string.substring(0, 5);
+/// const string = 'Dart is fun';
+/// print(string.substring(0, 4)); // 'Dart'
 /// ```
 /// You can use the plus (`+`) operator to concatenate strings:
 /// ```dart
-/// 'Dart ' + 'is ' + 'fun!'; // 'Dart is fun!'
+/// const string = 'Dart ' + 'is ' + 'fun!';
+/// print(string); // 'Dart is fun!'
 /// ```
 /// Adjacent string literals are concatenated automatically:
 /// ```dart
-/// 'Dart ' 'is ' 'fun!';    // 'Dart is fun!'
+/// const string = 'Dart ' 'is ' 'fun!';
+/// print(string); // 'Dart is fun!'
 /// ```
 /// You can use `${}` to interpolate the value of Dart expressions
 /// within strings. The curly braces can be omitted when evaluating identifiers:
 /// ```dart
-/// var string = 'dartlang';
-/// '$string has ${string.length} letters'; // 'dartlang has 8 letters'
+/// const string = 'dartlang';
+/// print('$string has ${string.length} letters'); // dartlang has 8 letters
 /// ```
 /// A string is represented by a sequence of Unicode UTF-16 code units
 /// accessible through the [codeUnitAt] or the [codeUnits] members:
 /// ```dart
-/// var string = 'Dart';
-/// string.codeUnitAt(0); // 68
-/// string.codeUnits;     // [68, 97, 114, 116]
+/// const string = 'Dart';
+/// final firstCodeUnit = string.codeUnitAt(0);
+/// print(firstCodeUnit); // 68, aka U+0044, the code point for 'D'.
+/// final allCodeUnits = string.codeUnits;
+/// print(allCodeUnits); // [68, 97, 114, 116]
 /// ```
-/// The string representation of code units is accessible through the index
-/// operator:
+/// A string representation of the individual code units is accessible through
+/// the index operator:
 /// ```dart
-/// string[0];            // 'D'
+/// const string = 'Dart';
+/// final charAtIndex = string[0];
+/// print(charAtIndex); // 'D'
 /// ```
 /// The characters of a string are encoded in UTF-16. Decoding UTF-16, which
 /// combines surrogate pairs, yields Unicode code points. Following a similar
-/// terminology to Go, we use the name 'rune' for an integer representing a
+/// terminology to Go, Dart uses the name 'rune' for an integer representing a
 /// Unicode code point. Use the [runes] property to get the runes of a string:
 /// ```dart
-/// string.runes.toList(); // [68, 97, 114, 116]
+/// const string = 'Dart';
+/// final runes = string.runes.toList();
+/// print(runes); // [68, 97, 114, 116]
 /// ```
 /// For a character outside the Basic Multilingual Plane (plane 0) that is
 /// composed of a surrogate pair, [runes] combines the pair and returns a
@@ -78,34 +86,38 @@
 /// pair: `0xD834` and `0xDD1E`. Using [codeUnits] returns the surrogate pair,
 /// and using `runes` returns their combined value:
 /// ```dart
-/// var clef = '\u{1D11E}';
-/// clef.codeUnits;         // [0xD834, 0xDD1E]
-/// clef.runes.toList();    // [0x1D11E]
+/// const clef = '\u{1D11E}';
+/// for (final item in clef.codeUnits) {
+///   print(item.toRadixString(16));
+///   // d834
+///   // dd1e
+/// }
+/// for (final item in clef.runes) {
+///   print(item.toRadixString(16)); // 1d11e
+/// }
 /// ```
 /// The `String` class cannot be extended or implemented. Attempting to do so
 /// yields a compile-time error.
 ///
 /// ## Other resources
 ///
-/// See [StringBuffer] to efficiently build a string incrementally. See
-/// [RegExp] to work with regular expressions.
-///
-/// Also see:
-///
+/// * [StringBuffer] to efficiently build a string incrementally.
+/// * [RegExp] to work with regular expressions.
 /// * [Strings and regular expressions](https://dart.dev/guides/libraries/library-tour#strings-and-regular-expressions)
 @pragma('vm:entry-point')
 abstract class String implements Comparable<String>, Pattern {
   /// Allocates a new string containing the specified [charCodes].
   ///
-  /// The [charCodes] can be both UTF-16 code units or runes.
+  /// The [charCodes] can be both UTF-16 code units and runes.
   /// If a char-code value is 16-bit, it is used as a code unit:
   /// ```dart
-  /// String.fromCharCodes([68]); // 'D'
+  /// final string = String.fromCharCodes([68]);
+  /// print(string); // D
   /// ```
   /// If a char-code value is greater than 16-bits, it is decomposed into a
   /// surrogate pair:
   /// ```dart
-  /// var clef = String.fromCharCodes([0x1D11E]);
+  /// final clef = String.fromCharCodes([0x1D11E]);
   /// clef.codeUnitAt(0); // 0xD834
   /// clef.codeUnitAt(1); // 0xDD1E
   /// ```
@@ -224,7 +236,7 @@
   /// a positive value if `this` is ordered after `other`,
   /// or zero if `this` and `other` are equivalent.
   ///
-  /// The ordering is the same as the ordering of the code points at the first
+  /// The ordering is the same as the ordering of the code units at the first
   /// position where the two strings differ.
   /// If one string is a prefix of the other,
   /// then the shorter string is ordered before the longer string.
@@ -232,28 +244,39 @@
   /// regard to the ordering.
   /// Ordering does not check for Unicode equivalence.
   /// The comparison is case sensitive.
+  /// ```dart
+  /// var relation = 'Dart'.compareTo('Go');
+  /// print(relation); // < 0
+  /// relation = 'Go'.compareTo('Forward');
+  /// print(relation); // > 0
+  /// relation = 'Forward'.compareTo('Forward');
+  /// print(relation); // 0
+  /// ```
   int compareTo(String other);
 
   /// Whether this string ends with [other].
   ///
   /// For example:
   /// ```dart
-  /// 'Dart'.endsWith('t'); // true
+  /// const string = 'Dart is open source';
+  /// print(string.endsWith('urce')); // true
   /// ```
   bool endsWith(String other);
 
   /// Whether this string starts with a match of [pattern].
   ///
   /// ```dart
-  /// var string = 'Dart';
-  /// string.startsWith('D');                       // true
-  /// string.startsWith(RegExp(r'[A-Z][a-z]')); // true
+  /// const string = 'Dart is open source';
+  /// print(string.startsWith('Dar')); // true
+  /// print(string.startsWith(RegExp(r'[A-Z][a-z]'))); // true
   /// ```
   /// If [index] is provided, this method checks if the substring starting
   /// at that index starts with a match of [pattern]:
   /// ```dart
-  /// string.startsWith('art', 1);                  // true
-  /// string.startsWith(RegExp(r'\w{3}'));      // true
+  /// const string = 'Dart';
+  /// print(string.startsWith('art', 0)); // false
+  /// print(string.startsWith('art', 1)); // true
+  /// print(string.startsWith(RegExp(r'\w{3}'), 2)); // false
   /// ```
   /// [index] must not be negative or greater than [length].
   ///
@@ -262,21 +285,23 @@
   /// The pattern works on the string as a whole, and does not extract
   /// a substring starting at [index] first:
   /// ```dart
-  /// string.startsWith(RegExp(r'^art'), 1);    // false
-  /// string.startsWith(RegExp(r'art'), 1);     // true
+  /// const string = 'Dart';
+  /// print(string.startsWith(RegExp(r'^art'), 1)); // false
+  /// print(string.startsWith(RegExp(r'art'), 1)); // true
   /// ```
   bool startsWith(Pattern pattern, [int index = 0]);
 
   /// Returns the position of the first match of [pattern] in this string,
   /// starting at [start], inclusive:
   /// ```dart
-  /// var string = 'Dartisans';
-  /// string.indexOf('art');                     // 1
-  /// string.indexOf(RegExp(r'[A-Z][a-z]')); // 0
+  /// const string = 'Dartisans';
+  /// print(string.indexOf('art')); // 1
+  /// print(string.indexOf(RegExp(r'[A-Z][a-z]'))); // 0
   /// ```
   /// Returns -1 if no match is found:
   /// ```dart
-  /// string.indexOf(RegExp(r'dart'));       // -1
+  /// const string = 'Dartisans';
+  /// string.indexOf(RegExp(r'dart')); // -1
   /// ```
   /// The [start] must be non-negative and not greater than [length].
   int indexOf(Pattern pattern, [int start = 0]);
@@ -285,13 +310,14 @@
   ///
   /// Finds a match of pattern by searching backward starting at [start]:
   /// ```dart
-  /// var string = 'Dartisans';
-  /// string.lastIndexOf('a');                    // 6
-  /// string.lastIndexOf(RegExp(r'a(r|n)'));      // 6
+  /// const string = 'Dartisans';
+  /// print(string.lastIndexOf('a')); // 6
+  /// print(string.lastIndexOf(RegExp(r'a(r|n)'))); // 6
   /// ```
   /// Returns -1 if [pattern] could not be found in this string.
   /// ```dart
-  /// string.lastIndexOf(RegExp(r'DART'));        // -1
+  /// const string = 'Dartisans';
+  /// print(string.lastIndexOf(RegExp(r'DART'))); // -1
   /// ```
   /// If [start] is omitted, search starts from the end of the string.
   /// If supplied, [start] must be non-negative and not greater than [length].
@@ -307,17 +333,17 @@
   ///
   /// Example:
   /// ```dart
-  /// 'dart' + 'lang'; // 'dartlang'
+  /// const string = 'dart' + 'lang'; // 'dartlang'
   /// ```
   String operator +(String other);
 
-  /// The substring of this string from [start],inclusive, to [end], exclusive.
+  /// The substring of this string from [start], inclusive, to [end], exclusive.
   ///
   /// Example:
   /// ```dart
-  /// var string = 'dartlang';
-  /// string.substring(1);    // 'artlang'
-  /// string.substring(1, 4); // 'art'
+  /// const string = 'dartlang';
+  /// var result = string.substring(1); // 'artlang'
+  /// result = string.substring(1, 4); // 'art'
   /// ```
   ///
   /// Both [start] and [end] must be non-negative and no greater than [length], and
@@ -329,13 +355,14 @@
   /// If the string contains leading or trailing whitespace, a new string with no
   /// leading and no trailing whitespace is returned:
   /// ```dart
-  /// '\tDart is fun\n'.trim(); // 'Dart is fun'
+  /// final trimmed = '\tDart is fun\n'.trim();
+  /// print(trimmed); // 'Dart is fun'
   /// ```
   /// Otherwise, the original string itself is returned:
   /// ```dart
-  /// var str1 = 'Dart';
-  /// var str2 = str1.trim();
-  /// identical(str1, str2);    // true
+  /// const string1 = 'Dart';
+  /// final string2 = string1.trim(); // 'Dart'
+  /// print(identical(string1, string2)); // true
   /// ```
   /// Whitespace is defined by the Unicode White_Space property (as defined in
   /// version 6.2 or later) and the BOM character, 0xFEFF.
@@ -364,11 +391,19 @@
   /// The string without any leading whitespace.
   ///
   /// As [trim], but only removes leading whitespace.
+  /// ```dart
+  /// final string = ' Dart '.trimLeft();
+  /// print(string); // 'Dart '
+  /// ```
   String trimLeft();
 
   /// The string without any trailing whitespace.
   ///
   /// As [trim], but only removes trailing whitespace.
+  /// ```dart
+  /// final string = ' Dart '.trimRight();
+  /// print(string); // ' Dart'
+  /// ```
   String trimRight();
 
   /// Creates a new string by concatenating this string with itself a number
@@ -377,6 +412,11 @@
   /// The result of `str * n` is equivalent to
   /// `str + str + ...`(n times)`... + str`.
   ///
+  /// ```dart
+  /// const string = 'Dart';
+  /// final multiplied = string * 3;
+  /// print(multiplied); // 'DartDartDart'
+  /// ```
   /// Returns an empty string if [times] is zero or negative.
   String operator *(int times);
 
@@ -385,6 +425,14 @@
   /// Returns a new string that prepends [padding] onto this string
   /// one time for each position the length is less than [width].
   ///
+  /// ```dart
+  /// const string = 'D';
+  /// print(string.padLeft(4)); // '   D'
+  /// print(string.padLeft(2, 'x')); // 'xD'
+  /// print(string.padLeft(4, 'y')); // 'yyyD'
+  /// print(string.padLeft(4, '>>')); // '>>>>>>D'
+  /// ```
+  ///
   /// If [width] is already smaller than or equal to `this.length`,
   /// no padding is added. A negative `width` is treated as zero.
   ///
@@ -393,7 +441,7 @@
   /// padding is a longer string representing a single character, like
   /// `"&nbsp;"` or `"\u{10002}`".
   /// In that case, the user should make sure that `this.length` is
-  /// the correct measure of the strings length.
+  /// the correct measure of the string's length.
   String padLeft(int width, [String padding = ' ']);
 
   /// Pads this string on the right if it is shorter than [width].
@@ -401,6 +449,14 @@
   /// Returns a new string that appends [padding] after this string
   /// one time for each position the length is less than [width].
   ///
+  /// ```dart
+  /// const string = 'D';
+  /// print(string.padRight(4)); // 'D    '
+  /// print(string.padRight(2, 'x')); // 'Dx'
+  /// print(string.padRight(4, 'y')); // 'Dyyy'
+  /// print(string.padRight(4, '>>')); // 'D>>>>>>'
+  /// ```
+  ///
   /// If [width] is already smaller than or equal to `this.length`,
   /// no padding is added. A negative `width` is treated as zero.
   ///
@@ -409,22 +465,23 @@
   /// padding is a longer string representing a single character, like
   /// `"&nbsp;"` or `"\u{10002}`".
   /// In that case, the user should make sure that `this.length` is
-  /// the correct measure of the strings length.
+  /// the correct measure of the string's length.
   String padRight(int width, [String padding = ' ']);
 
   /// Whether this string contains a match of [other].
   ///
   /// Example:
   /// ```dart
-  /// var string = 'Dart strings';
-  /// string.contains('D');                     // true
-  /// string.contains(RegExp(r'[A-Z]'));    // true
+  /// const string = 'Dart strings';
+  /// final containsD = string.contains('D'); // true
+  /// final containsUpperCase = string.contains(RegExp(r'[A-Z]')); // true
   /// ```
   /// If [startIndex] is provided, this method matches only at or after that
   /// index:
   /// ```dart
-  /// string.contains('D', 1);                  // false
-  /// string.contains(RegExp(r'[A-Z]'), 1); // false
+  /// const string = 'Dart strings';
+  /// final containsD = string.contains(RegExp('D'), 0); // true
+  /// final caseSensitive = string.contains(RegExp(r'[A-Z]'), 1); // false
   /// ```
   /// The [startIndex] must not be negative or greater than [length].
   bool contains(Pattern other, [int startIndex = 0]);
@@ -437,12 +494,21 @@
   /// Example:
   /// ```dart
   /// '0.0001'.replaceFirst(RegExp(r'0'), ''); // '.0001'
-  /// '0.0001'.replaceFirst(RegExp(r'0'), '7', 1); // '0.7001'
+  /// '0.0001'.replaceFirst(RegExp(r'0'), '7', 1);  // '0.7001'
   /// ```
   String replaceFirst(Pattern from, String to, [int startIndex = 0]);
 
   /// Replace the first occurrence of [from] in this string.
   ///
+  /// ```dart
+  /// const string = 'Dart is fun';
+  /// print(string.replaceFirstMapped(
+  ///     'fun', (m) => 'open source')); // Dart is open source
+  ///
+  /// print(string.replaceFirstMapped(
+  ///     RegExp(r'\w(\w*)'), (m) => '<${m[0]}-${m[1]}>')); // <Dart-art> is fun
+  /// ```
+  ///
   /// Returns a new string, which is this string
   /// except that the first match of [from], starting from [startIndex],
   /// is replaced by the result of calling [replace] with the match object.
@@ -460,7 +526,7 @@
   /// 'resume'.replaceAll(RegExp(r'e'), 'é'); // 'résumé'
   /// ```
   /// Notice that the [replace] string is not interpreted. If the replacement
-  /// depends on the match (for example on a [RegExp]'s capture groups), use
+  /// depends on the match (for example, on a [RegExp]'s capture groups), use
   /// the [replaceAllMapped] method instead.
   String replaceAll(Pattern from, String replace);
 
@@ -479,11 +545,12 @@
   /// The function defined below converts each word in a string to simplified
   /// 'pig latin' using [replaceAllMapped]:
   /// ```dart
-  /// pigLatin(String words) => words.replaceAllMapped(
+  /// String pigLatin(String words) => words.replaceAllMapped(
   ///     RegExp(r'\b(\w*?)([aeiou]\w*)', caseSensitive: false),
   ///     (Match m) => "${m[2]}${m[1]}${m[1]!.isEmpty ? 'way' : 'ay'}");
   ///
-  ///     pigLatin('I have a secret now!'); // 'Iway avehay away ecretsay ownay!'
+  /// final result = pigLatin('I have a secret now!');
+  /// print(result); // 'Iway avehay away ecretsay ownay!'
   /// ```
   String replaceAllMapped(Pattern from, String Function(Match match) replace);
 
@@ -493,6 +560,12 @@
   /// ```dart
   /// this.substring(0, start) + replacement + this.substring(end)
   /// ```
+  /// Example:
+  /// ```dart
+  /// const string = 'Dart is fun';
+  /// final result = string.replaceRange(8, null, 'open source');
+  /// print(result); // Dart is open source
+  /// ```
   /// The [start] and [end] indices must specify a valid range of this string.
   /// That is `0 <= start <= end <= this.length`.
   /// If [end] is `null`, it defaults to [length].
@@ -505,8 +578,9 @@
   /// and returns the list of the substrings between the matches,
   /// before the first match, and after the last match.
   /// ```dart
-  /// var string = "Hello world!";
-  /// string.split(" ");                      // ["Hello", "world!"];
+  /// const string = 'Hello world!';
+  /// final splitted = string.split(' ');
+  /// print(splitted); // [Hello, world!];
   /// ```
   /// If the pattern doesn't match this string at all,
   /// the result is always a list containing only the original string.
@@ -525,22 +599,22 @@
   /// then the empty substring between the two matches is not
   /// included in the result.
   /// ```dart
-  /// var string = "abba";
-  /// var re = RegExp(r"b*");
+  /// const string = 'abba';
+  /// final re = RegExp(r'b*');
   /// // re.allMatches(string) will find four matches:
   /// // * empty match before first "a".
   /// // * match of "bb"
   /// // * empty match after "bb", before second "a"
   /// // * empty match after second "a".
-  /// print(string.split(re));  // ["a", "a"]
+  /// print(string.split(re)); // [a, a]
   /// ```
   ///
   /// A non-empty match at the start or end of the string, or after another
   /// match, is not treated specially, and will introduce empty substrings
   /// in the result:
   /// ```dart
-  /// var string = "abbaa";
-  /// string.split("a"); // ["", "bb", "", ""]
+  /// const string = 'abbaa';
+  /// final splitted = string.split('a'); // ['', 'bb', '', '']
   /// ```
   ///
   /// If this string is the empty string, the result is an empty list
@@ -549,34 +623,40 @@
   /// (It is still a list containing the original empty string `[""]`
   /// if the pattern doesn't match).
   /// ```dart
-  /// var string = "";
-  /// string.split("");                       // []
-  /// string.split("a");                      // [""]
+  /// const string = '';
+  /// print(string.split('')); // []
+  /// print(string.split('a')); // []
   /// ```
   ///
   /// Splitting with an empty pattern splits the string into single-code unit
   /// strings.
   /// ```dart
-  /// var string = "Pub";
-  /// string.split("");                       // ["P", "u", "b"]
+  /// const string = 'Pub';
+  /// print(string.split('')); // [P, u, b]
   ///
   /// // Same as:
-  /// [for (var unit in string.codeUnits)
-  ///     String.fromCharCode(unit)];         // ["P", "u", "b"]
+  /// var codeUnitStrings = [
+  ///   for (final unit in string.codeUnits) String.fromCharCode(unit)
+  /// ];
+  /// print(codeUnitStrings); // [P, u, b]
   /// ```
   ///
   /// Splitting happens at UTF-16 code unit boundaries,
   /// and not at rune (Unicode code point) boundaries:
   /// ```dart
   /// // String made up of two code units, but one rune.
-  /// var string = '\u{1D11E}';
-  /// string.split('');  // ["\ud834", "\udd1e"] - 2 unpaired surrogate values
+  /// const string = '\u{1D11E}';
+  /// final splitted = string.split('');
+  /// print(splitted); // ['\ud834', '\udd1e'] - 2 unpaired surrogate values
   /// ```
   /// To get a list of strings containing the individual runes of a string,
   /// you should not use split.
   /// You can instead get a string for each rune as follows:
   /// ```dart
-  /// [for (var run in string.runes) String.fromCharCode(rune)]
+  /// const string = '\u{1F642}';
+  /// for (final rune in string.runes) {
+  ///   print(String.fromCharCode(rune));
+  /// }
   /// ```
   List<String> split(Pattern pattern);
 
@@ -600,9 +680,10 @@
   ///
   /// Then all the converted parts are concatenated into the resulting string.
   /// ```dart
-  /// 'Eats shoots leaves'.splitMapJoin((RegExp(r'shoots')),
-  ///     onMatch:    (m) => '${m[0]}',  // (or no onMatch at all)
-  ///     onNonMatch: (n) => '*'); // Result: "*shoots*"
+  /// final result = 'Eats shoots leaves'.splitMapJoin(RegExp(r'shoots'),
+  ///     onMatch: (m) => '${m[0]}', // (or no onMatch at all)
+  ///     onNonMatch: (n) => '*');
+  /// print(result); // *shoots*
   /// ```
   String splitMapJoin(Pattern pattern,
       {String Function(Match)? onMatch, String Function(String)? onNonMatch});
@@ -622,7 +703,7 @@
   /// If the string is already in all lower case, this method returns `this`.
   /// ```dart
   /// 'ALPHABET'.toLowerCase(); // 'alphabet'
-  /// 'abc'.toLowerCase();      // 'abc'
+  /// 'abc'.toLowerCase(); // 'abc'
   /// ```
   /// This function uses the language independent Unicode mapping and thus only
   /// works in some languages.
@@ -634,7 +715,7 @@
   /// If the string is already in all upper case, this method returns `this`.
   /// ```dart
   /// 'alphabet'.toUpperCase(); // 'ALPHABET'
-  /// 'ABC'.toUpperCase();      // 'ABC'
+  /// 'ABC'.toUpperCase(); // 'ABC'
   /// ```
   /// This function uses the language independent Unicode mapping and thus only
   /// works in some languages.
@@ -706,7 +787,7 @@
   ///
   /// When created, there is no [current] value.
   /// A [moveNext] will use the rune starting at [index] the current value,
-  /// and a [movePrevious] will use the rune ending just before [index] as the
+  /// and a [movePrevious] will use the rune ending just before [index] as
   /// the current value.
   ///
   /// The [index] position must not be in the middle of a surrogate pair.
diff --git a/sdk/lib/core/string_buffer.dart b/sdk/lib/core/string_buffer.dart
index 9f5a615..675dcd3 100644
--- a/sdk/lib/core/string_buffer.dart
+++ b/sdk/lib/core/string_buffer.dart
@@ -9,8 +9,71 @@
 /// Allows for the incremental building of a string using `write*()` methods.
 /// The strings are concatenated to a single string only when [toString] is
 /// called.
+///
+/// Example:
+/// ```dart
+/// final buffer = StringBuffer('DART');
+/// print(buffer.length); // 4
+/// ```
+/// To add the string representation of an object, as returned by
+/// [Object.toString], to the buffer, use [write].
+/// Is also used for adding a string directly.
+/// ```
+/// buffer.write(' is open source');
+/// print(buffer.length); // 19
+/// print(buffer); // DART is open source
+///
+/// const int dartYear = 2011;
+/// buffer
+///   ..write(' since ') // Writes a string.
+///   ..write(dartYear); // Writes an int.
+/// print(buffer); // DART is open source since 2011
+/// print(buffer.length); // 30
+/// ```
+/// To add a newline after the object's string representation, use [writeln].
+/// Calling [writeln] with no argument adds a single newline to the buffer.
+/// ```
+/// buffer.writeln(); // Contains "DART is open source since 2011\n".
+/// buffer.writeln('-' * (buffer.length - 1)); // 30 '-'s and a newline.
+/// print(buffer.length); // 62
+/// ```
+/// To write multiple objects to the buffer, use [writeAll].
+/// ```
+/// const separator = '-';
+/// buffer.writeAll(['Dart', 'is', 'fun!'], separator);
+/// print(buffer.length); // 74
+/// print(buffer);
+/// // DART is open source since 2011
+/// // ------------------------------
+/// // Dart-is-fun!
+/// ```
+/// To add the string representation of a Unicode code point, `charCode`,
+/// to the buffer, use [writeCharCode].
+/// ```
+/// buffer.writeCharCode(0x0A); // LF (line feed)
+/// buffer.writeCharCode(0x44); // 'D'
+/// buffer.writeCharCode(0x61); // 'a'
+/// buffer.writeCharCode(0x72); // 'r'
+/// buffer.writeCharCode(0x74); // 't'
+/// print(buffer.length); // 79
+/// ```
+/// To convert the content to a single string, use [toString].
+/// ```
+/// final text = buffer.toString();
+/// print(text);
+/// // DART is open source since 2011
+/// // ------------------------------
+/// // Dart-is-fun!
+/// // Dart
+/// ```
+/// To clear the buffer, so that it can be reused, use [clear].
+/// ```
+/// buffer.clear();
+/// print(buffer.isEmpty); // true
+/// print(buffer.length); // 0
+/// ```
 class StringBuffer implements StringSink {
-  /// Creates the string buffer with an initial content.
+  /// Creates a string buffer containing the provided [content].
   external StringBuffer([Object content = ""]);
 
   /// Returns the length of the content that has been accumulated so far.
diff --git a/sdk/lib/core/uri.dart b/sdk/lib/core/uri.dart
index 3e24c54..cd38662 100644
--- a/sdk/lib/core/uri.dart
+++ b/sdk/lib/core/uri.dart
@@ -26,20 +26,92 @@
 
 /// A parsed URI, such as a URL.
 ///
-/// **See also:**
+/// To create a URI with specific components, use [new Uri]:
+/// ```dart
+/// var httpsUri = Uri(
+///     scheme: 'https',
+///     host: 'dart.dev',
+///     path: '/guides/libraries/library-tour',
+///     fragment: 'numbers');
+/// print(httpsUri); // https://dart.dev/guides/libraries/library-tour#numbers
 ///
+/// httpsUri = Uri(
+///     scheme: 'https',
+///     host: 'example.com',
+///     path: '/page/',
+///     queryParameters: {'search': 'blue', 'limit': '10'});
+/// print(httpsUri); // https://example.com/page/?search=blue&limit=10
+///
+/// final mailtoUri = Uri(
+///     scheme: 'mailto',
+///     path: 'John.Doe@example.com',
+///     queryParameters: {'subject': 'Example'});
+/// print(mailtoUri); // mailto:John.Doe@example.com?subject=Example
+/// ```
+///
+/// ## HTTP and HTTPS URI
+/// To create a URI with https scheme, use [Uri.https] or [Uri.http]:
+/// ```dart
+/// final httpsUri = Uri.https('example.com', 'api/fetch', {'limit': '10'});
+/// print(httpsUri); // https://example.com/api/fetch?limit=10
+/// ```
+/// ## File URI
+/// To create a URI from file path, use [Uri.file]:
+/// ```dart
+/// final fileUriUnix =
+///     Uri.file(r'/home/myself/images/image.png', windows: false);
+/// print(fileUriUnix); // file:///home/myself/images/image.png
+///
+/// final fileUriWindows =
+///     Uri.file(r'C:\Users\myself\Documents\image.png', windows: true);
+/// print(fileUriWindows); // file:///C:/Users/myself/Documents/image.png
+/// ```
+/// If the URI is not a file URI, calling this throws [UnsupportedError].
+///
+/// ## Directory URI
+/// Like [Uri.file] except that a non-empty URI path ends in a slash.
+/// ```dart
+/// final fileDirectory =
+///     Uri.directory('/home/myself/data/image', windows: false);
+/// print(fileDirectory); // file:///home/myself/data/image/
+///
+/// final fileDirectoryWindows = Uri.directory('/data/images', windows: true);
+/// print(fileDirectoryWindows); //  file:///data/images/
+/// ```
+///
+/// ## URI from string
+/// To create a URI from string, use [Uri.parse] or [Uri.tryParse]:
+/// ```dart
+/// final uri = Uri.parse(
+///     'https://dart.dev/guides/libraries/library-tour#utility-classes');
+/// print(uri); // https://dart.dev
+/// print(uri.isScheme('https')); // true
+/// print(uri.origin); // https://dart.dev
+/// print(uri.host); // dart.dev
+/// print(uri.authority); // dart.dev
+/// print(uri.port); // 443
+/// print(uri.path); // guides/libraries/library-tour
+/// print(uri.pathSegments); // [guides, libraries, library-tour]
+/// print(uri.fragment); // utility-classes
+/// print(uri.hasQuery); // false
+/// print(uri.data); // null
+/// ```
+///
+/// **See also:**
 /// * [URIs][uris] in the [library tour][libtour]
-/// * [RFC-3986](http://tools.ietf.org/html/rfc3986)
+/// * [RFC-3986](https://tools.ietf.org/html/rfc3986)
+/// * [RFC-2396](https://tools.ietf.org/html/rfc2396)
+/// * [RFC-2045](https://tools.ietf.org/html/rfc2045)
 ///
 /// [uris]: https://dart.dev/guides/libraries/library-tour#uris
 /// [libtour]: https://dart.dev/guides/libraries/library-tour
 abstract class Uri {
   /// The natural base URI for the current platform.
   ///
-  /// When running in a browser this is the current URL of the current page
+  /// When running in a browser, this is the current URL of the current page
   /// (from `window.location.href`).
   ///
-  /// When not running in a browser this is the file URI referencing
+  /// When not running in a browser, this is the file URI referencing
   /// the current working directory.
   external static Uri get base;
 
@@ -93,7 +165,7 @@
   /// When [query] is used, the provided string should be a valid URI query,
   /// but invalid characters, other than general delimiters,
   /// will be escaped if necessary.
-  /// When [queryParameters] is used the query is built from the
+  /// When [queryParameters] is used, the query is built from the
   /// provided map. Each key and value in the map is percent-encoded
   /// and joined using equal and ampersand characters.
   /// A value in the map must be either a string, or an [Iterable] of strings,
@@ -110,8 +182,24 @@
   ///
   /// The fragment component is set through [fragment].
   /// It should be a valid URI fragment, but invalid characters other than
-  /// general delimiters, are escaped if necessary.
+  /// general delimiters are escaped if necessary.
   /// If [fragment] is omitted or `null`, the URI has no fragment part.
+  ///
+  /// Example:
+  /// ```dart
+  /// final httpsUri = Uri(
+  ///     scheme: 'https',
+  ///     host: 'dart.dev',
+  ///     path: 'guides/libraries/library-tour',
+  ///     fragment: 'numbers');
+  /// print(httpsUri); // https://dart.dev/guides/libraries/library-tour#numbers
+  ///
+  /// final mailtoUri = Uri(
+  ///     scheme: 'mailto',
+  ///     path: 'John.Doe@example.com',
+  ///     queryParameters: {'subject': 'Example'});
+  /// print(mailtoUri); // mailto:John.Doe@example.com?subject=Example
+  /// ```
   factory Uri(
       {String? scheme,
       String? userInfo,
@@ -125,20 +213,19 @@
 
   /// Creates a new `http` URI from authority, path and query.
   ///
-  /// Examples:
-  ///
+  /// Example:
   /// ```dart
-  /// // http://example.org/path?q=dart.
-  /// Uri.http("example.org", "/path", { "q" : "dart" });
+  /// var uri = Uri.http('example.org', '/path', { 'q' : 'dart' });
+  /// print(uri); // http://example.org/path?q=dart
   ///
-  /// // http://user:pass@localhost:8080
-  /// Uri.http("user:pass@localhost:8080", "");
+  /// uri = Uri.http('user:password@localhost:8080', '');
+  /// print(uri); // http://user:password@localhost:8080
   ///
-  /// // http://example.org/a%20b
-  /// Uri.http("example.org", "a b");
+  /// uri = Uri.http('example.org', 'a b');
+  /// print(uri); // http://example.org/a%20b
   ///
-  /// // http://example.org/a%252F
-  /// Uri.http("example.org", "/a%2F");
+  /// uri = Uri.http('example.org', '/a%2F');
+  /// print(uri); // http://example.org/a%252F
   /// ```
   ///
   /// The `scheme` is always set to `http`.
@@ -161,6 +248,21 @@
   ///
   /// This constructor is the same as [Uri.http] except for the scheme
   /// which is set to `https`.
+  ///
+  /// Example:
+  /// ```dart
+  /// var uri = Uri.https('example.org', '/path', {'q': 'dart'});
+  /// print(uri); // https://example.org/path?q=dart
+  ///
+  /// uri = Uri.https('user:password@localhost:8080', '');
+  /// print(uri); // https://user:password@localhost:8080
+  ///
+  /// uri = Uri.https('example.org', 'a b');
+  /// print(uri); // https://example.org/a%20b
+  ///
+  /// uri = Uri.https('example.org', '/a%2F');
+  /// print(uri); // https://example.org/a%252F
+  /// ```
   factory Uri.https(String authority, String unencodedPath,
       [Map<String, dynamic>? queryParameters]) = _Uri.https;
 
@@ -171,7 +273,7 @@
   /// This path is interpreted using either Windows or non-Windows
   /// semantics.
   ///
-  /// With non-Windows semantics the slash (`/`) is used to separate
+  /// With non-Windows semantics, the slash (`/`) is used to separate
   /// path segments in the input [path].
   ///
   /// With Windows semantics, backslash (`\`) and forward-slash (`/`)
@@ -182,14 +284,14 @@
   /// If the path starts with a path separator, an absolute URI (with the
   /// `file` scheme and an empty authority) is created.
   /// Otherwise a relative URI reference with no scheme or authority is created.
-  /// One exception from this rule is that when Windows semantics is used
+  /// One exception to this rule is that when Windows semantics is used
   /// and the path starts with a drive letter followed by a colon (":") and a
   /// path separator, then an absolute URI is created.
   ///
   /// The default for whether to use Windows or non-Windows semantics
-  /// determined from the platform Dart is running on. When running in
+  /// is determined from the platform Dart is running on. When running in
   /// the standalone VM, this is detected by the VM based on the
-  /// operating system. When running in a browser non-Windows semantics
+  /// operating system. When running in a browser, non-Windows semantics
   /// is always used.
   ///
   /// To override the automatic detection of which semantics to use pass
@@ -197,51 +299,49 @@
   /// semantics and passing `false` will use non-Windows semantics.
   ///
   /// Examples using non-Windows semantics:
-  ///
   /// ```dart
   /// // xxx/yyy
-  /// Uri.file("xxx/yyy", windows: false);
+  /// Uri.file('xxx/yyy', windows: false);
   ///
   /// // xxx/yyy/
-  /// Uri.file("xxx/yyy/", windows: false);
+  /// Uri.file('xxx/yyy/', windows: false);
   ///
   /// // file:///xxx/yyy
-  /// Uri.file("/xxx/yyy", windows: false);
+  /// Uri.file('/xxx/yyy', windows: false);
   ///
   /// // file:///xxx/yyy/
-  /// Uri.file("/xxx/yyy/", windows: false);
+  /// Uri.file('/xxx/yyy/', windows: false);
   ///
   /// // C%3A
-  /// Uri.file("C:", windows: false);
+  /// Uri.file('C:', windows: false);
   /// ```
   ///
   /// Examples using Windows semantics:
-  ///
   /// ```dart
   /// // xxx/yyy
-  /// Uri.file(r"xxx\yyy", windows: true);
+  /// Uri.file(r'xxx\yyy', windows: true);
   ///
   /// // xxx/yyy/
-  /// Uri.file(r"xxx\yyy\", windows: true);
+  /// Uri.file(r'xxx\yyy\', windows: true);
   ///
   /// file:///xxx/yyy
-  /// Uri.file(r"\xxx\yyy", windows: true);
+  /// Uri.file(r'\xxx\yyy', windows: true);
   ///
   /// file:///xxx/yyy/
-  /// Uri.file(r"\xxx\yyy/", windows: true);
+  /// Uri.file(r'\xxx\yyy/', windows: true);
   ///
   /// // file:///C:/xxx/yyy
-  /// Uri.file(r"C:\xxx\yyy", windows: true);
+  /// Uri.file(r'C:\xxx\yyy', windows: true);
   ///
   /// // This throws an error. A path with a drive letter, but no following
   /// // path, is not allowed.
-  /// Uri.file(r"C:", windows: true);
+  /// Uri.file(r'C:', windows: true);
   ///
   /// // This throws an error. A path with a drive letter is not absolute.
-  /// Uri.file(r"C:xxx\yyy", windows: true);
+  /// Uri.file(r'C:xxx\yyy', windows: true);
   ///
   /// // file://server/share/file
-  /// Uri.file(r"\\server\share\file", windows: true);
+  /// Uri.file(r'\\server\share\file', windows: true);
   /// ```
   ///
   /// If the path passed is not a valid file path, an error is thrown.
@@ -252,17 +352,27 @@
   /// If [path] is not empty, and it doesn't end in a directory separator,
   /// then a slash is added to the returned URI's path.
   /// In all other cases, the result is the same as returned by `Uri.file`.
+  ///
+  /// Example:
+  /// ```dart
+  /// final fileDirectory = Uri.directory('data/images', windows: false);
+  /// print(fileDirectory); // data/images/
+  ///
+  /// final fileDirectoryWindows =
+  ///    Uri.directory(r'C:\data\images', windows: true);
+  /// print(fileDirectoryWindows); // file:///C:/data/images/
+  /// ```
   factory Uri.directory(String path, {bool? windows}) = _Uri.directory;
 
   /// Creates a `data:` URI containing the [content] string.
   ///
-  /// Converts the content to a bytes using [encoding] or the charset specified
+  /// Converts the content to bytes using [encoding] or the charset specified
   /// in [parameters] (defaulting to US-ASCII if not specified or unrecognized),
   /// then encodes the bytes into the resulting data URI.
   ///
-  /// Defaults to encoding using percent-encoding (any non-ASCII or non-URI-valid
-  /// bytes is replaced by a percent encoding). If [base64] is true, the bytes
-  /// are instead encoded using [base64].
+  /// Defaults to encoding using percent-encoding (any non-ASCII or
+  /// non-URI-valid bytes is replaced by a percent encoding). If [base64] is
+  /// true, the bytes are instead encoded using [base64].
   ///
   /// If [encoding] is not provided and [parameters] has a `charset` entry,
   /// that name is looked up using [Encoding.getByName],
@@ -280,6 +390,16 @@
   /// as an omitted `charset` parameter defaults to meaning `US-ASCII`.
   ///
   /// To read the content back, use [UriData.contentAsString].
+  ///
+  /// Example:
+  /// ```dart
+  /// final uri = Uri.dataFromString(
+  ///   'example content',
+  ///   mimeType: 'text/plain',
+  ///   parameters: <String, String>{'search': 'file', 'max': '10'},
+  /// );
+  /// print(uri); // data:;search=name;max=10,example%20content
+  /// ```
   factory Uri.dataFromString(String content,
       {String? mimeType,
       Encoding? encoding,
@@ -307,6 +427,12 @@
   /// in the data URI, the character is percent-escaped. If the character is
   /// non-ASCII, it is first UTF-8 encoded and then the bytes are percent
   /// encoded.
+  ///
+  /// Example:
+  /// ```dart
+  /// final uri = Uri.dataFromBytes([68, 97, 114, 116]);
+  /// print(uri); // data:application/octet-stream;base64,RGFydA==
+  /// ```
   factory Uri.dataFromBytes(List<int> bytes,
       {String mimeType = "application/octet-stream",
       Map<String, String>? parameters,
@@ -336,7 +462,7 @@
 
   /// The user info part of the authority component.
   ///
-  /// Th value is the empty string if there is no user info in the
+  /// The value is the empty string if there is no user info in the
   /// authority component.
   String get userInfo;
 
@@ -363,7 +489,7 @@
   ///
   /// The path is the actual substring of the URI representing the path,
   /// and it is encoded where necessary. To get direct access to the decoded
-  /// path use [pathSegments].
+  /// path, use [pathSegments].
   ///
   /// The path value is the empty string if there is no path component.
   String get path;
@@ -372,7 +498,7 @@
   ///
   /// The value is the actual substring of the URI representing the query part,
   /// and it is encoded where necessary.
-  /// To get direct access to the decoded query use [queryParameters].
+  /// To get direct access to the decoded query, use [queryParameters].
   ///
   /// The value is the empty string if there is no query component.
   String get query;
@@ -385,8 +511,8 @@
 
   /// The URI path split into its segments.
   ///
-  /// Each of the segments in the list have been decoded.
-  /// If the path is empty the empty list will
+  /// Each of the segments in the list has been decoded.
+  /// If the path is empty, the empty list will
   /// be returned. A leading slash `/` does not affect the segments returned.
   ///
   /// The list is unmodifiable and will throw [UnsupportedError] on any
@@ -395,10 +521,11 @@
 
   /// The URI query split into a map according to the rules
   /// specified for FORM post in the [HTML 4.01 specification section
-  /// 17.13.4](http://www.w3.org/TR/REC-html40/interact/forms.html#h-17.13.4 "HTML 4.01 section 17.13.4").
+  /// 17.13.4](https://www.w3.org/TR/REC-html40/interact/forms.html#h-17.13.4
+  /// "HTML 4.01 section 17.13.4").
   ///
   /// Each key and value in the resulting map has been decoded.
-  /// If there is no query the empty map is returned.
+  /// If there is no query, the empty map is returned.
   ///
   /// Keys in the query string that have no value are mapped to the
   /// empty string.
@@ -407,20 +534,36 @@
   /// The [queryParametersAll] getter can provide a map
   /// that maps keys to all of their values.
   ///
+  /// Example:
+  /// ```dart import:convert
+  /// final uri =
+  ///     Uri.parse('https://example.com/api/fetch?limit=10,20,30&max=100');
+  /// print(jsonEncode(uri.queryParameters));
+  /// // {"limit":"10,20,30","max":"100"}
+  /// ```
+  ///
   /// The map is unmodifiable.
   Map<String, String> get queryParameters;
 
   /// Returns the URI query split into a map according to the rules
   /// specified for FORM post in the [HTML 4.01 specification section
-  /// 17.13.4](http://www.w3.org/TR/REC-html40/interact/forms.html#h-17.13.4 "HTML 4.01 section 17.13.4").
+  /// 17.13.4](https://www.w3.org/TR/REC-html40/interact/forms.html#h-17.13.4
+  /// "HTML 4.01 section 17.13.4").
   ///
   /// Each key and value in the resulting map has been decoded. If there is no
-  /// query the map is empty.
+  /// query, the map is empty.
   ///
   /// Keys are mapped to lists of their values. If a key occurs only once,
   /// its value is a singleton list. If a key occurs with no value, the
   /// empty string is used as the value for that occurrence.
   ///
+  /// Example:
+  /// ```dart import:convert
+  /// final uri =
+  ///     Uri.parse('https://example.com/api/fetch?limit=10,20,30&max=100');
+  /// print(jsonEncode(uri.queryParameters)); // {"limit":"10,20,30","max":"100"}
+  /// ```
+  ///
   /// The map and the lists it contains are unmodifiable.
   Map<String, List<String>> get queryParametersAll;
 
@@ -462,7 +605,7 @@
   /// It is an error if the scheme is not "http" or "https", or if the host name
   /// is missing or empty.
   ///
-  /// See: http://www.w3.org/TR/2011/WD-html5-20110405/origin-0.html#origin
+  /// See: https://www.w3.org/TR/2011/WD-html5-20110405/origin-0.html#origin
   String get origin;
 
   /// Whether the scheme of this [Uri] is [scheme].
@@ -472,8 +615,11 @@
   ///
   /// Example:
   /// ```dart
-  /// var uri = Uri.parse("http://example.com/");
-  /// print(uri.isScheme("HTTP"));  // Prints true.
+  /// var uri = Uri.parse('http://example.com');
+  /// print(uri.isScheme('HTTP')); // true
+  ///
+  /// final uriNoScheme = Uri(host: 'example.com');
+  /// print(uriNoScheme.isScheme('HTTP')); // false
   /// ```
   ///
   /// An empty [scheme] string matches a URI with no scheme
@@ -485,22 +631,22 @@
   /// The returned path has either Windows or non-Windows
   /// semantics.
   ///
-  /// For non-Windows semantics the slash ("/") is used to separate
+  /// For non-Windows semantics, the slash ("/") is used to separate
   /// path segments.
   ///
-  /// For Windows semantics the backslash ("\\") separator is used to
+  /// For Windows semantics, the backslash ("\\") separator is used to
   /// separate path segments.
   ///
-  /// If the URI is absolute the path starts with a path separator
+  /// If the URI is absolute, the path starts with a path separator
   /// unless Windows semantics is used and the first path segment is a
-  /// drive letter. When Windows semantics is used a host component in
+  /// drive letter. When Windows semantics is used, a host component in
   /// the uri in interpreted as a file server and a UNC path is
   /// returned.
   ///
   /// The default for whether to use Windows or non-Windows semantics
-  /// determined from the platform Dart is running on. When running in
-  /// the standalone VM this is detected by the VM based on the
-  /// operating system. When running in a browser non-Windows semantics
+  /// is determined from the platform Dart is running on. When running in
+  /// the standalone VM, this is detected by the VM based on the
+  /// operating system. When running in a browser, non-Windows semantics
   /// is always used.
   ///
   /// To override the automatic detection of which semantics to use pass
@@ -508,10 +654,10 @@
   /// semantics and passing `false` will use non-Windows semantics.
   ///
   /// If the URI ends with a slash (i.e. the last path component is
-  /// empty) the returned file path will also end with a slash.
+  /// empty), the returned file path will also end with a slash.
   ///
-  /// With Windows semantics URIs starting with a drive letter cannot
-  /// be relative to the current drive on the designated drive. That is
+  /// With Windows semantics, URIs starting with a drive letter cannot
+  /// be relative to the current drive on the designated drive. That is,
   /// for the URI `file:///c:abc` calling `toFilePath` will throw as a
   /// path segment cannot contain colon on Windows.
   ///
@@ -536,10 +682,10 @@
   ///                               // cannot contain colon on Windows.
   /// Uri.parse("file://server/share/file");  // \\server\share\file
   /// ```
-  /// If the URI is not a file URI calling this throws
+  /// If the URI is not a file URI, calling this throws
   /// [UnsupportedError].
   ///
-  /// If the URI cannot be converted to a file path calling this throws
+  /// If the URI cannot be converted to a file path, calling this throws
   /// [UnsupportedError].
   // TODO(lrn): Deprecate and move functionality to File class or similar.
   // The core libraries should not worry about the platform.
@@ -576,31 +722,35 @@
   /// Each part that is not provided will default to the corresponding
   /// value from this `Uri` instead.
   ///
-  /// This method is different from [Uri.resolve] which overrides in a
+  /// This method is different from [Uri.resolve], which overrides in a
   /// hierarchical manner,
   /// and can instead replace each part of a `Uri` individually.
   ///
   /// Example:
   /// ```dart
-  /// Uri uri1 = Uri.parse("a://b@c:4/d/e?f#g");
-  /// Uri uri2 = uri1.replace(scheme: "A", path: "D/E/E", fragment: "G");
-  /// print(uri2);  // prints "a://b@c:4/D/E/E?f#G"
+  /// final uri1 = Uri.parse(
+  ///     'http://dart.dev/guides/libraries/library-tour#utility-classes');
+  ///
+  /// final uri2 = uri1.replace(
+  ///     scheme: 'https',
+  ///     path: 'guides/libraries/library-tour',
+  ///     fragment: 'uris');
+  /// print(uri2); // https://dart.dev/guides/libraries/library-tour#uris
   /// ```
   /// This method acts similarly to using the `Uri` constructor with
   /// some of the arguments taken from this `Uri`. Example:
-  /// ```dart
-  /// Uri uri3 = Uri(
-  ///     scheme: "A",
+  /// ``` dart continued
+  /// final Uri uri3 = Uri(
+  ///     scheme: 'https',
   ///     userInfo: uri1.userInfo,
   ///     host: uri1.host,
-  ///     port: uri1.port,
-  ///     path: "D/E/E",
+  ///     port: uri2.port,
+  ///     path: '/guides/language/language-tour',
   ///     query: uri1.query,
-  ///     fragment: "G");
-  /// print(uri3);  // prints "a://b@c:4/D/E/E?f#G"
-  /// print(uri2 == uri3);  // prints true.
+  ///     fragment: null);
+  /// print(uri3); // https://dart.dev/guides/language/language-tour
   /// ```
-  /// Using this method can be seen as a shorthand for the `Uri` constructor
+  /// Using this method can be seen as shorthand for the `Uri` constructor
   /// call above, but may also be slightly faster because the parts taken
   /// from this `Uri` need not be checked for validity again.
   Uri replace(
@@ -617,6 +767,13 @@
   /// Creates a `Uri` that differs from this only in not having a fragment.
   ///
   /// If this `Uri` does not have a fragment, it is itself returned.
+  ///
+  /// Example:
+  /// ```dart
+  /// final uri =
+  ///     Uri.parse('https://example.org:8080/foo/bar#frag').removeFragment();
+  /// print(uri); // https://example.org:8080/foo/bar
+  /// ```
   Uri removeFragment();
 
   /// Resolve [reference] as an URI relative to `this`.
@@ -629,16 +786,17 @@
   /// See [resolveUri] for details.
   Uri resolve(String reference);
 
-  /// Resolve [reference] as an URI relative to `this`.
+  /// Resolve [reference] as a URI relative to `this`.
   ///
   /// Returns the resolved URI.
   ///
   /// The algorithm "Transform Reference" for resolving a reference is described
-  /// in [RFC-3986 Section 5](http://tools.ietf.org/html/rfc3986#section-5 "RFC-1123").
+  /// in [RFC-3986 Section 5](https://tools.ietf.org/html/rfc3986#section-5
+  /// "RFC-1123").
   ///
   /// Updated to handle the case where the base URI is just a relative path -
-  /// that is: when it has no scheme and no authority and the path does not start
-  /// with a slash.
+  /// that is: when it has no scheme and no authority and the path does not
+  /// start with a slash.
   /// In that case, the paths are combined without removing leading "..", and
   /// an empty path is not converted to "/".
   Uri resolveUri(Uri reference);
@@ -648,7 +806,7 @@
   /// A normalized path does not contain `.` segments or non-leading `..`
   /// segments.
   /// Only a relative path with no scheme or authority may contain
-  /// leading `..` segments,
+  /// leading `..` segments;
   /// a path that starts with `/` will also drop any leading `..` segments.
   ///
   /// This uses the same normalization strategy as `Uri().resolve(this)`.
@@ -666,6 +824,15 @@
   ///
   /// If the [uri] string is not valid as a URI or URI reference,
   /// a [FormatException] is thrown.
+  ///
+  /// Example:
+  /// ```dart
+  /// final uri =
+  ///     Uri.parse('https://example.com/api/fetch?limit=10,20,30&max=100');
+  /// print(uri); // https://example.com/api/fetch?limit=10,20,30&max=100
+  ///
+  /// Uri.parse('::Not valid URI::'); // Throws FormatException.
+  /// ```
   static Uri parse(String uri, [int start = 0, int? end]) {
     // This parsing will not validate percent-encoding, IPv6, etc.
     // When done splitting into parts, it will call, e.g., [_makeFragment]
@@ -963,6 +1130,17 @@
   /// of [uri], and only the substring from `start` to `end` is parsed as a URI.
   ///
   /// Returns `null` if the [uri] string is not valid as a URI or URI reference.
+  ///
+  /// Example:
+  /// ```dart
+  /// final uri = Uri.tryParse(
+  ///     'https://dart.dev/guides/libraries/library-tour#utility-classes', 0,
+  ///     16);
+  /// print(uri); // https://dart.dev
+  ///
+  /// var notUri = Uri.tryParse('::Not valid URI::');
+  /// print(notUri); // null
+  /// ```
   static Uri? tryParse(String uri, [int start = 0, int? end]) {
     // TODO: Optimize to avoid throwing-and-recatching.
     try {
@@ -977,19 +1155,26 @@
   ///
   /// All characters except uppercase and lowercase letters, digits and
   /// the characters `-_.!~*'()` are percent-encoded. This is the
-  /// set of characters specified in RFC 2396 and the which is
+  /// set of characters specified in RFC 2396 and which is
   /// specified for the encodeUriComponent in ECMA-262 version 5.1.
   ///
-  /// When manually encoding path segments or query components remember
+  /// When manually encoding path segments or query components, remember
   /// to encode each part separately before building the path or query
   /// string.
   ///
   /// For encoding the query part consider using
   /// [encodeQueryComponent].
   ///
-  /// To avoid the need for explicitly encoding use the [pathSegments]
+  /// To avoid the need for explicitly encoding, use the [pathSegments]
   /// and [queryParameters] optional named arguments when constructing
   /// a [Uri].
+  ///
+  /// Example:
+  /// ```dart
+  /// const request = 'http://example.com/search=Dart';
+  /// final encoded = Uri.encodeComponent(request);
+  /// print(encoded); // http%3A%2F%2Fexample.com%2Fsearch%3DDart
+  /// ```
   static String encodeComponent(String component) {
     return _Uri._uriEncode(_Uri._unreserved2396Table, component, utf8, false);
   }
@@ -1024,7 +1209,7 @@
    * [queryParameters] optional named arguments when constructing a
    * [Uri].
    *
-   * See http://www.w3.org/TR/html401/interact/forms.html#h-17.13.4.2 for more
+   * See https://www.w3.org/TR/html401/interact/forms.html#h-17.13.4.2 for more
    * details.
    */
   static String encodeQueryComponent(String component,
@@ -1035,14 +1220,21 @@
   /// Decodes the percent-encoding in [encodedComponent].
   ///
   /// Note that decoding a URI component might change its meaning as
-  /// some of the decoded characters could be characters with are
+  /// some of the decoded characters could be characters which are
   /// delimiters for a given URI component type. Always split a URI
   /// component using the delimiters for the component before decoding
   /// the individual parts.
   ///
-  /// For handling the [path] and [query] components consider using
+  /// For handling the [path] and [query] components, consider using
   /// [pathSegments] and [queryParameters] to get the separated and
   /// decoded component.
+  ///
+  /// Example:
+  /// ```dart
+  /// final decoded =
+  ///     Uri.decodeComponent('http%3A%2F%2Fexample.com%2Fsearch%3DDart');
+  /// print(decoded); // http://example.com/search=Dart
+  /// ```
   static String decodeComponent(String encodedComponent) {
     return _Uri._uriDecode(
         encodedComponent, 0, encodedComponent.length, utf8, false);
@@ -1066,7 +1258,14 @@
   /// All characters except uppercase and lowercase letters, digits and
   /// the characters `!#$&'()*+,-./:;=?@_~` are percent-encoded. This
   /// is the set of characters specified in in ECMA-262 version 5.1 for
-  /// the encodeURI function .
+  /// the encodeURI function.
+  ///
+  /// Example:
+  /// ```dart
+  /// final encoded =
+  ///     Uri.encodeFull('https://example.com/api/query?search= dart is');
+  /// print(encoded); // https://example.com/api/query?search=%20dart%20is
+  /// ```
   static String encodeFull(String uri) {
     return _Uri._uriEncode(_Uri._encodeFullTable, uri, utf8, false);
   }
@@ -1075,24 +1274,41 @@
   ///
   /// Note that decoding a full URI might change its meaning as some of
   /// the decoded characters could be reserved characters. In most
-  /// cases an encoded URI should be parsed into components using
+  /// cases, an encoded URI should be parsed into components using
   /// [Uri.parse] before decoding the separate components.
+  ///
+  /// Example:
+  /// ```dart
+  /// final decoded =
+  ///     Uri.decodeFull('https://example.com/api/query?search=%20dart%20is');
+  /// print(decoded); // https://example.com/api/query?search= dart is
+  /// ```
   static String decodeFull(String uri) {
     return _Uri._uriDecode(uri, 0, uri.length, utf8, false);
   }
 
   /// Splits the [query] into a map according to the rules
   /// specified for FORM post in the [HTML 4.01 specification section
-  /// 17.13.4](http://www.w3.org/TR/REC-html40/interact/forms.html#h-17.13.4 "HTML 4.01 section 17.13.4").
+  /// 17.13.4](https://www.w3.org/TR/REC-html40/interact/forms.html#h-17.13.4
+  /// "HTML 4.01 section 17.13.4").
   ///
   /// Each key and value in the returned map has been decoded. If the [query]
-  /// is the empty string an empty map is returned.
+  /// is the empty string, an empty map is returned.
   ///
   /// Keys in the query string that have no value are mapped to the
   /// empty string.
   ///
-  /// Each query component will be decoded using [encoding]. The default encoding
-  /// is UTF-8.
+  /// Each query component will be decoded using [encoding]. The default
+  /// encoding is UTF-8.
+  ///
+  /// Example:
+  /// ```dart import:convert
+  /// final queryStringMap =
+  ///     Uri.splitQueryString('limit=10&max=100&search=Dart%20is%20fun');
+  /// print(jsonEncode(queryStringMap));
+  /// // {"limit":"10","max":"100","search":"Dart is fun"}
+  ///
+  /// ```
   static Map<String, String> splitQueryString(String query,
       {Encoding encoding = utf8}) {
     return query.split("&").fold({}, (map, element) {
@@ -1170,7 +1386,7 @@
   /// representation.
   ///
   /// Acts on the substring from [start] to [end]. If [end] is omitted, it
-  /// defaults ot the end of the string.
+  /// defaults to the end of the string.
   ///
   /// Some examples of IPv6 addresses:
   ///  * `::1`
@@ -1188,7 +1404,7 @@
     //  - The last two parts may be replaced by an IPv4 "dotted-quad" address.
 
     // Helper function for reporting a badly formatted IPv6 address.
-    void error(String msg, [position]) {
+    void error(String msg, int? position) {
       throw FormatException('Illegal IPv6 address, $msg', host, position);
     }
 
@@ -1204,7 +1420,7 @@
       return value;
     }
 
-    if (host.length < 2) error('address is too short');
+    if (host.length < 2) error('address is too short', null);
     List<int> parts = [];
     bool wildcardSeen = false;
     // Set if seeing a ".", suggesting that there is an IPv4 address.
@@ -1238,7 +1454,7 @@
         seenDot = true;
       }
     }
-    if (parts.length == 0) error('too few parts');
+    if (parts.length == 0) error('too few parts', null);
     bool atEnd = (partStart == end);
     bool isLastWildcard = (parts.last == -1);
     if (atEnd && !isLastWildcard) {
@@ -1255,10 +1471,10 @@
     }
     if (wildcardSeen) {
       if (parts.length > 7) {
-        error('an address with a wildcard must have less than 7 parts');
+        error('an address with a wildcard must have less than 7 parts', null);
       }
     } else if (parts.length != 8) {
-      error('an address without a wildcard must contain exactly 8 parts');
+      error('an address without a wildcard must contain exactly 8 parts', null);
     }
     List<int> bytes = Uint8List(16);
     for (int i = 0, index = 0; i < parts.length; i++) {
@@ -2181,7 +2397,7 @@
 
   /// Performs RFC 3986 Percent-Encoding Normalization.
   ///
-  /// Returns a replacement string that should be replace the original escape.
+  /// Returns a replacement string that should replace the original escape.
   /// Returns null if no replacement is necessary because the escape is
   /// not for an unreserved character and is already non-lower-case.
   ///
@@ -2266,12 +2482,12 @@
   }
 
   /// Runs through component checking that each character is valid and
-  /// normalize percent escapes.
+  /// normalizes percent escapes.
   ///
   /// Uses [charTable] to check if a non-`%` character is allowed.
   /// Each `%` character must be followed by two hex digits.
-  /// If the hex-digits are lower case letters, they are converted to
-  /// upper case.
+  /// If the hex-digits are lowercase letters, they are converted to
+  /// uppercase.
   ///
   /// Returns `null` if the original content was already normalized.
   static String? _normalize(
@@ -2430,7 +2646,7 @@
   /// Removing the ".." from a "bar/foo/.." sequence results in "bar/"
   /// (trailing "/"). If the entire path is removed (because it contains as
   /// many ".." segments as real segments), the result is "./".
-  /// This is different from an empty string, which represents "no path",
+  /// This is different from an empty string, which represents "no path"
   /// when you resolve it against a base URI with a path with a non-empty
   /// final segment.
   static String _normalizeRelativePath(String path, bool allowScheme) {
@@ -2811,7 +3027,7 @@
   /// If [plusToSpace] is `true`, plus characters will be converted to spaces.
   ///
   /// The decoder will create a byte-list of the percent-encoded parts, and then
-  /// decode the byte-list using [encoding]. The default encodings UTF-8.
+  /// decode the byte-list using [encoding]. The default encoding is UTF-8.
   static String _uriDecode(
       String text, int start, int end, Encoding encoding, bool plusToSpace) {
     assert(0 <= start);
@@ -3115,7 +3331,7 @@
 /// Data URIs are non-hierarchical URIs that can contain any binary data.
 /// They are defined by [RFC 2397](https://tools.ietf.org/html/rfc2397).
 ///
-/// This class allows parsing the URI text and extracting individual parts of the
+/// This class allows parsing the URI text, extracting individual parts of the
 /// URI, as well as building the URI text from structured parts.
 class UriData {
   static const int _noScheme = -1;
@@ -3137,7 +3353,7 @@
   /// The first separator ends the mime type. We don't bother with finding
   /// the '/' inside the mime type.
   ///
-  /// Each two separators after that marks a parameter key and value.
+  /// Each two separators after that mark a parameter key and value.
   ///
   /// If there is a single separator left, it ends the "base64" marker.
   ///
@@ -3244,7 +3460,7 @@
   /// until just before the ',' before the data, or before a `;base64,`
   /// marker.
   ///
-  /// Of an [indices] list is passed, separator indices are stored in that
+  /// If an [indices] list is passed, separator indices are stored in that
   /// list.
   static void _writeUri(
       String? mimeType,
@@ -3335,7 +3551,7 @@
   /// it valid, and existing escapes are case normalized.
   ///
   /// Accessing the individual parts may fail later if they turn out to have
-  /// content that can't be decoded successfully as a string, for example if
+  /// content that cannot be decoded successfully as a string, for example if
   /// existing percent escapes represent bytes that cannot be decoded
   /// by the chosen [Encoding] (see [contentAsString]).
   ///
@@ -3410,7 +3626,7 @@
   /// If the parameters of the media type contains a `charset` parameter
   /// then this returns its value, otherwise it returns `US-ASCII`,
   /// which is the default charset for data URIs.
-  /// If the value contain non-ASCII percent escapes, they are decoded as UTF-8.
+  /// If the values contain non-ASCII percent escapes, they are decoded as UTF-8.
   ///
   /// If the MIME type representation in the URI text contains URI escapes,
   /// they are unescaped in the returned string.
@@ -3497,7 +3713,7 @@
   /// If the content is Base64 encoded, it will be decoded to bytes and then
   /// decoded to a string using [encoding].
   /// If encoding is omitted, the value of a `charset` parameter is used
-  /// if it is recognized by [Encoding.getByName], otherwise it defaults to
+  /// if it is recognized by [Encoding.getByName]; otherwise it defaults to
   /// the [ascii] encoding, which is the default encoding for data URIs
   /// that do not specify an encoding.
   ///
@@ -3725,7 +3941,7 @@
 // Initial state for scheme validation.
 const int _schemeStart = 20;
 
-/// Transition tables used to scan a URI to determine its structure.
+/// Transition tables are used to scan a URI to determine its structure.
 ///
 /// The tables represent a state machine with output.
 ///
@@ -3740,13 +3956,13 @@
 /// and a 3-bit index into the output table.
 ///
 /// For URI scanning, only characters in the range U+0020 through U+007E are
-/// interesting, all characters outside that range are treated the same.
-/// The tables only contain 96 entries, representing that characters in the
+/// interesting; all characters outside that range are treated the same.
+/// The tables only contain 96 entries, representing the characters in the
 /// interesting range, plus one more to represent all values outside the range.
 /// The character entries are stored in one `Uint8List` per state, with the
 /// transition for a character at position `character ^ 0x60`,
 /// which maps the range U+0020 .. U+007F into positions 0 .. 95.
-/// All remaining characters are mapped to position 31 (`0x7f ^ 0x60`) which
+/// All remaining characters are mapped to position 31 (`0x7f ^ 0x60`), which
 /// represents the transition for all remaining characters.
 final List<Uint8List> _scannerTables = _createTables();
 
diff --git a/sdk/lib/ffi/abi_specific.dart b/sdk/lib/ffi/abi_specific.dart
new file mode 100644
index 0000000..560044a
--- /dev/null
+++ b/sdk/lib/ffi/abi_specific.dart
@@ -0,0 +1,53 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+part of dart.ffi;
+
+/// The supertype of all [Abi]-specific integer types.
+///
+/// [Abi]-specific integers should extend this class and annotate it with
+/// [AbiSpecificIntegerMapping] to declare the integer size and signedness
+/// for [Abi.values].
+///
+/// For example:
+///
+/// ```
+/// /// Represents a `uintptr_t` in C.
+/// ///
+/// /// [UintPtr] is not constructible in the Dart code and serves purely as
+/// /// marker in type signatures.
+/// @AbiSpecificIntegerMapping({
+///   Abi.androidArm: Uint32(),
+///   Abi.androidArm64: Uint64(),
+///   Abi.androidIA32: Uint32(),
+///   Abi.androidX64: Uint64(),
+///   Abi.fuchsiaArm64: Uint64(),
+///   Abi.fuchsiaX64: Uint64(),
+///   Abi.iosArm: Uint32(),
+///   Abi.iosArm64: Uint64(),
+///   Abi.linuxArm: Uint32(),
+///   Abi.linuxArm64: Uint64(),
+///   Abi.linuxIA32: Uint32(),
+///   Abi.linuxX64: Uint64(),
+///   Abi.macosArm64: Uint64(),
+///   Abi.macosX64: Uint64(),
+///   Abi.windowsIA32: Uint32(),
+///   Abi.windowsX64: Uint64(),
+/// })
+/// class UintPtr extends AbiSpecificInteger {
+///   const UintPtr();
+/// }
+/// ```
+class AbiSpecificInteger extends NativeType {
+  const AbiSpecificInteger();
+}
+
+/// Mapping for a subtype of [AbiSpecificInteger].
+///
+/// See documentation on [AbiSpecificInteger].
+class AbiSpecificIntegerMapping {
+  final Map<Abi, NativeType> mapping;
+
+  const AbiSpecificIntegerMapping(this.mapping);
+}
diff --git a/sdk/lib/ffi/ffi.dart b/sdk/lib/ffi/ffi.dart
index 00eee44..eba4ea8 100644
--- a/sdk/lib/ffi/ffi.dart
+++ b/sdk/lib/ffi/ffi.dart
@@ -16,6 +16,7 @@
 import 'dart:typed_data';
 
 part 'abi.dart';
+part 'abi_specific.dart';
 part 'native_type.dart';
 part 'allocation.dart';
 part 'annotations.dart';
@@ -738,6 +739,22 @@
   external T operator [](int index);
 }
 
+/// Extension on [Pointer] specialized for the type argument
+/// [AbiSpecificInteger].
+extension AbiSpecificIntegerPointer<T extends AbiSpecificInteger>
+    on Pointer<T> {
+  /// The integer at [address].
+  external int get value;
+
+  external void set value(int value);
+
+  /// The integer at `address + sizeOf<T>() * index`.
+  external int operator [](int index);
+
+  /// The integer at `address + sizeOf<T>() * index`.
+  external void operator []=(int index, int value);
+}
+
 /// Bounds checking indexing methods on [Array]s of [Pointer].
 extension PointerArray<T extends NativeType> on Array<Pointer<T>> {
   external Pointer<T> operator [](int index);
@@ -764,6 +781,13 @@
   external void operator []=(int index, Array<T> value);
 }
 
+/// Bounds checking indexing methods on [Array]s of [AbiSpecificInteger].
+extension AbiSpecificIntegerArray on Array<AbiSpecificInteger> {
+  external int operator [](int index);
+
+  external void operator []=(int index, int value);
+}
+
 /// Extension to retrieve the native `Dart_Port` from a [SendPort].
 extension NativePort on SendPort {
   /// The native port of this [SendPort].
diff --git a/sdk/lib/ffi/ffi_sources.gni b/sdk/lib/ffi/ffi_sources.gni
index f7b2838..b725fe0 100644
--- a/sdk/lib/ffi/ffi_sources.gni
+++ b/sdk/lib/ffi/ffi_sources.gni
@@ -7,6 +7,7 @@
 
   # The above file needs to be first as it lists the parts below.
   "abi.dart",
+  "abi_specific.dart",
   "allocation.dart",
   "annotations.dart",
   "dynamic_library.dart",
diff --git a/sdk/lib/html/dart2js/html_dart2js.dart b/sdk/lib/html/dart2js/html_dart2js.dart
index cc93c1e..182872b 100644
--- a/sdk/lib/html/dart2js/html_dart2js.dart
+++ b/sdk/lib/html/dart2js/html_dart2js.dart
@@ -57,7 +57,7 @@
         applyExtension;
 import 'dart:_interceptors'
     show
-        Interceptor,
+        JavaScriptObject,
         JavaScriptFunction,
         JSExtendableArray,
         JSUInt31,
@@ -176,7 +176,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-abstract class AbstractWorker extends Interceptor implements EventTarget {
+abstract class AbstractWorker extends JavaScriptObject implements EventTarget {
   // To suppress missing implicit constructor warnings.
   factory AbstractWorker._() {
     throw new UnsupportedError("Not supported");
@@ -469,7 +469,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("AccessibleNodeList")
-class AccessibleNodeList extends Interceptor {
+class AccessibleNodeList extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AccessibleNodeList._() {
     throw new UnsupportedError("Not supported");
@@ -705,7 +705,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("AnimationEffectReadOnly")
-class AnimationEffectReadOnly extends Interceptor {
+class AnimationEffectReadOnly extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AnimationEffectReadOnly._() {
     throw new UnsupportedError("Not supported");
@@ -785,7 +785,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("AnimationEffectTimingReadOnly")
-class AnimationEffectTimingReadOnly extends Interceptor {
+class AnimationEffectTimingReadOnly extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AnimationEffectTimingReadOnly._() {
     throw new UnsupportedError("Not supported");
@@ -869,7 +869,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("AnimationTimeline")
-class AnimationTimeline extends Interceptor {
+class AnimationTimeline extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AnimationTimeline._() {
     throw new UnsupportedError("Not supported");
@@ -1226,7 +1226,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("AuthenticatorResponse")
-class AuthenticatorResponse extends Interceptor {
+class AuthenticatorResponse extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AuthenticatorResponse._() {
     throw new UnsupportedError("Not supported");
@@ -1329,7 +1329,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("BackgroundFetchFetch")
-class BackgroundFetchFetch extends Interceptor {
+class BackgroundFetchFetch extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory BackgroundFetchFetch._() {
     throw new UnsupportedError("Not supported");
@@ -1342,7 +1342,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("BackgroundFetchManager")
-class BackgroundFetchManager extends Interceptor {
+class BackgroundFetchManager extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory BackgroundFetchManager._() {
     throw new UnsupportedError("Not supported");
@@ -1449,7 +1449,7 @@
 // http://www.whatwg.org/specs/web-apps/current-work/multipage/browsers.html#barprop
 @deprecated // standard
 @Native("BarProp")
-class BarProp extends Interceptor {
+class BarProp extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory BarProp._() {
     throw new UnsupportedError("Not supported");
@@ -1462,7 +1462,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("BarcodeDetector")
-class BarcodeDetector extends Interceptor {
+class BarcodeDetector extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory BarcodeDetector._() {
     throw new UnsupportedError("Not supported");
@@ -1582,7 +1582,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Blob")
-class Blob extends Interceptor {
+class Blob extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Blob._() {
     throw new UnsupportedError("Not supported");
@@ -1649,7 +1649,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("BluetoothRemoteGATTDescriptor")
-class BluetoothRemoteGattDescriptor extends Interceptor {
+class BluetoothRemoteGattDescriptor extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory BluetoothRemoteGattDescriptor._() {
     throw new UnsupportedError("Not supported");
@@ -1671,7 +1671,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Body")
-class Body extends Interceptor {
+class Body extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Body._() {
     throw new UnsupportedError("Not supported");
@@ -1896,7 +1896,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("BudgetState")
-class BudgetState extends Interceptor {
+class BudgetState extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory BudgetState._() {
     throw new UnsupportedError("Not supported");
@@ -2006,7 +2006,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("CacheStorage")
-class CacheStorage extends Interceptor {
+class CacheStorage extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CacheStorage._() {
     throw new UnsupportedError("Not supported");
@@ -2299,7 +2299,7 @@
  * * [CanvasGradient](http://www.w3.org/TR/2010/WD-2dcontext-20100304/#canvasgradient) from W3C.
  */
 @Native("CanvasGradient")
-class CanvasGradient extends Interceptor {
+class CanvasGradient extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CanvasGradient._() {
     throw new UnsupportedError("Not supported");
@@ -2350,7 +2350,7 @@
  * * [CanvasPattern](http://www.w3.org/TR/2010/WD-2dcontext-20100304/#canvaspattern) from W3C.
  */
 @Native("CanvasPattern")
-class CanvasPattern extends Interceptor {
+class CanvasPattern extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CanvasPattern._() {
     throw new UnsupportedError("Not supported");
@@ -2367,7 +2367,7 @@
 }
 
 @Native("CanvasRenderingContext2D")
-class CanvasRenderingContext2D extends Interceptor
+class CanvasRenderingContext2D extends JavaScriptObject
     implements CanvasRenderingContext {
   // To suppress missing implicit constructor warnings.
   factory CanvasRenderingContext2D._() {
@@ -3017,7 +3017,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-abstract class ChildNode extends Interceptor {
+abstract class ChildNode extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ChildNode._() {
     throw new UnsupportedError("Not supported");
@@ -3034,7 +3034,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Client")
-class Client extends Interceptor {
+class Client extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Client._() {
     throw new UnsupportedError("Not supported");
@@ -3055,7 +3055,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Clients")
-class Clients extends Interceptor {
+class Clients extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Clients._() {
     throw new UnsupportedError("Not supported");
@@ -3232,7 +3232,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("CookieStore")
-class CookieStore extends Interceptor {
+class CookieStore extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CookieStore._() {
     throw new UnsupportedError("Not supported");
@@ -3260,7 +3260,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Coordinates")
-class Coordinates extends Interceptor {
+class Coordinates extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Coordinates._() {
     throw new UnsupportedError("Not supported");
@@ -3285,7 +3285,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Credential")
-class Credential extends Interceptor {
+class Credential extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Credential._() {
     throw new UnsupportedError("Not supported");
@@ -3300,7 +3300,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("CredentialUserData")
-class CredentialUserData extends Interceptor {
+class CredentialUserData extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CredentialUserData._() {
     throw new UnsupportedError("Not supported");
@@ -3316,7 +3316,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("CredentialsContainer")
-class CredentialsContainer extends Interceptor {
+class CredentialsContainer extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CredentialsContainer._() {
     throw new UnsupportedError("Not supported");
@@ -3356,7 +3356,7 @@
 @SupportedBrowser(SupportedBrowser.CHROME)
 @SupportedBrowser(SupportedBrowser.SAFARI)
 @Native("Crypto")
-class Crypto extends Interceptor {
+class Crypto extends JavaScriptObject {
   TypedData getRandomValues(TypedData array) {
     return _getRandomValues(array);
   }
@@ -3382,7 +3382,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("CryptoKey")
-class CryptoKey extends Interceptor {
+class CryptoKey extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CryptoKey._() {
     throw new UnsupportedError("Not supported");
@@ -3402,7 +3402,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("CSS")
-class Css extends Interceptor {
+class Css extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Css._() {
     throw new UnsupportedError("Not supported");
@@ -3850,7 +3850,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("CSSRule")
-class CssRule extends Interceptor {
+class CssRule extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CssRule._() {
     throw new UnsupportedError("Not supported");
@@ -3960,7 +3960,8 @@
 //   CSSPropertyNames.in
 
 @Native("CSSStyleDeclaration,MSStyleCSSProperties,CSS2Properties")
-class CssStyleDeclaration extends Interceptor with CssStyleDeclarationBase {
+class CssStyleDeclaration extends JavaScriptObject
+    with CssStyleDeclarationBase {
   factory CssStyleDeclaration() => new CssStyleDeclaration.css('');
 
   factory CssStyleDeclaration.css(String css) {
@@ -7060,6 +7061,14 @@
     setProperty('font-weight', value, '');
   }
 
+  /** Gets the value of "gap" */
+  String get gap => getPropertyValue('gap');
+
+  /** Sets the value of "gap" */
+  set gap(String value) {
+    setProperty('gap', value, '');
+  }
+
   /** Gets the value of "grid" */
   String get grid => getPropertyValue('grid');
 
@@ -7996,6 +8005,14 @@
     setProperty('right', value, '');
   }
 
+  /** Gets the value of "row-gap" */
+  String get rowGap => getPropertyValue('row-gap');
+
+  /** Sets the value of "row-gap" */
+  set rowGap(String value) {
+    setProperty('row-gap', value, '');
+  }
+
   /** Gets the value of "rtl-ordering" */
   String get rtlOrdering => getPropertyValue('rtl-ordering');
 
@@ -8725,7 +8742,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("CSSStyleValue")
-class CssStyleValue extends Interceptor {
+class CssStyleValue extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CssStyleValue._() {
     throw new UnsupportedError("Not supported");
@@ -8749,7 +8766,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("CSSTransformComponent")
-class CssTransformComponent extends Interceptor {
+class CssTransformComponent extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CssTransformComponent._() {
     throw new UnsupportedError("Not supported");
@@ -8880,7 +8897,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("CSSVariableReferenceValue")
-class CssVariableReferenceValue extends Interceptor {
+class CssVariableReferenceValue extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CssVariableReferenceValue._() {
     throw new UnsupportedError("Not supported");
@@ -8936,7 +8953,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("CustomElementRegistry")
-class CustomElementRegistry extends Interceptor {
+class CustomElementRegistry extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CustomElementRegistry._() {
     throw new UnsupportedError("Not supported");
@@ -9104,7 +9121,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DataTransfer")
-class DataTransfer extends Interceptor {
+class DataTransfer extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DataTransfer._() {
     throw new UnsupportedError("Not supported");
@@ -9144,16 +9161,23 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DataTransferItem")
-class DataTransferItem extends Interceptor {
+class DataTransferItem extends JavaScriptObject {
   Entry getAsEntry() {
     Entry entry = _webkitGetAsEntry() as Entry;
 
-    if (entry.isFile!)
+    if (entry.isFile!) {
       applyExtension('FileEntry', entry);
-    else if (entry.isDirectory!)
+      applyExtension('webkitFileSystemFileEntry', entry);
+      applyExtension('FileSystemFileEntry', entry);
+    } else if (entry.isDirectory!) {
       applyExtension('DirectoryEntry', entry);
-    else
+      applyExtension('webkitFileSystemDirectoryEntry', entry);
+      applyExtension('FileSystemDirectoryEntry', entry);
+    } else {
       applyExtension('Entry', entry);
+      applyExtension('webkitFileSystemEntry', entry);
+      applyExtension('FileSystemEntry', entry);
+    }
 
     return entry;
   }
@@ -9179,7 +9203,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DataTransferItemList")
-class DataTransferItemList extends Interceptor {
+class DataTransferItemList extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DataTransferItemList._() {
     throw new UnsupportedError("Not supported");
@@ -9298,7 +9322,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DeprecatedStorageInfo")
-class DeprecatedStorageInfo extends Interceptor {
+class DeprecatedStorageInfo extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DeprecatedStorageInfo._() {
     throw new UnsupportedError("Not supported");
@@ -9321,7 +9345,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DeprecatedStorageQuota")
-class DeprecatedStorageQuota extends Interceptor {
+class DeprecatedStorageQuota extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DeprecatedStorageQuota._() {
     throw new UnsupportedError("Not supported");
@@ -9385,7 +9409,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DetectedBarcode")
-class DetectedBarcode extends Interceptor {
+class DetectedBarcode extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DetectedBarcode._() {
     throw new UnsupportedError("Not supported");
@@ -9408,7 +9432,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DetectedFace")
-class DetectedFace extends Interceptor {
+class DetectedFace extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DetectedFace._() {
     throw new UnsupportedError("Not supported");
@@ -9428,7 +9452,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DetectedText")
-class DetectedText extends Interceptor {
+class DetectedText extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DetectedText._() {
     throw new UnsupportedError("Not supported");
@@ -9450,7 +9474,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DeviceAcceleration")
-class DeviceAcceleration extends Interceptor {
+class DeviceAcceleration extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DeviceAcceleration._() {
     throw new UnsupportedError("Not supported");
@@ -9532,7 +9556,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DeviceRotationRate")
-class DeviceRotationRate extends Interceptor {
+class DeviceRotationRate extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DeviceRotationRate._() {
     throw new UnsupportedError("Not supported");
@@ -9580,7 +9604,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-@Native("DirectoryEntry")
+@Native(
+    "DirectoryEntry,webkitFileSystemDirectoryEntry,FileSystemDirectoryEntry")
 class DirectoryEntry extends Entry {
   /**
    * Create a new directory with the specified `path`. If `exclusive` is true,
@@ -9595,6 +9620,9 @@
   DirectoryReader createReader() {
     DirectoryReader reader = _createReader();
     applyExtension('DirectoryReader', reader);
+    applyExtension('WebKitDirectoryReader', reader);
+    applyExtension('webkitFileSystemDirectoryReader', reader);
+    applyExtension('FileSystemDirectoryReader', reader);
     return reader;
   }
 
@@ -9715,6 +9743,8 @@
     var completer = new Completer<Entry>();
     __getFile(path, options, (value) {
       applyExtension('FileEntry', value);
+      applyExtension('webkitFileSystemFileEntry', value);
+      applyExtension('FileSystemFileEntry', value);
       completer.complete(value);
     }, (error) {
       completer.completeError(error);
@@ -9741,8 +9771,9 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-@Native("DirectoryReader")
-class DirectoryReader extends Interceptor {
+@Native(
+    "DirectoryReader,WebKitDirectoryReader,webkitFileSystemDirectoryReader,FileSystemDirectoryReader")
+class DirectoryReader extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DirectoryReader._() {
     throw new UnsupportedError("Not supported");
@@ -9757,10 +9788,18 @@
     _readEntries((values) {
       values.forEach((value) {
         applyExtension('Entry', value);
+        applyExtension('webkitFileSystemEntry', value);
+        applyExtension('FileSystemEntry', value);
         Entry entry = value as Entry;
-        if (entry.isFile!)
+        if (entry.isFile!) {
           applyExtension('FileEntry', entry);
-        else if (entry.isDirectory!) applyExtension('DirectoryEntry', entry);
+          applyExtension('webkitFileSystemFileEntry', entry);
+          applyExtension('FileSystemFileEntry', entry);
+        } else if (entry.isDirectory!) {
+          applyExtension('DirectoryEntry', entry);
+          applyExtension('webkitFileSystemDirectoryEntry', entry);
+          applyExtension('FileSystemDirectoryEntry', entry);
+        }
       });
       completer.complete(new List<Entry>.from(values));
     }, (error) {
@@ -10584,7 +10623,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DocumentOrShadowRoot")
-class DocumentOrShadowRoot extends Interceptor {
+class DocumentOrShadowRoot extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DocumentOrShadowRoot._() {
     throw new UnsupportedError("Not supported");
@@ -10634,7 +10673,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DOMError")
-class DomError extends Interceptor {
+class DomError extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DomError._() {
     throw new UnsupportedError("Not supported");
@@ -10660,7 +10699,7 @@
 
 @Unstable()
 @Native("DOMException")
-class DomException extends Interceptor {
+class DomException extends JavaScriptObject {
   static const String INDEX_SIZE = 'IndexSizeError';
   static const String HIERARCHY_REQUEST = 'HierarchyRequestError';
   static const String WRONG_DOCUMENT = 'WrongDocumentError';
@@ -10719,7 +10758,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DOMImplementation")
-class DomImplementation extends Interceptor {
+class DomImplementation extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DomImplementation._() {
     throw new UnsupportedError("Not supported");
@@ -10741,7 +10780,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Iterator")
-class DomIterator extends Interceptor {
+class DomIterator extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DomIterator._() {
     throw new UnsupportedError("Not supported");
@@ -10976,7 +11015,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DOMMatrixReadOnly")
-class DomMatrixReadOnly extends Interceptor {
+class DomMatrixReadOnly extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DomMatrixReadOnly._() {
     throw new UnsupportedError("Not supported");
@@ -11122,7 +11161,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DOMParser")
-class DomParser extends Interceptor {
+class DomParser extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DomParser._() {
     throw new UnsupportedError("Not supported");
@@ -11215,7 +11254,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DOMPointReadOnly")
-class DomPointReadOnly extends Interceptor {
+class DomPointReadOnly extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DomPointReadOnly._() {
     throw new UnsupportedError("Not supported");
@@ -11286,7 +11325,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DOMQuad")
-class DomQuad extends Interceptor {
+class DomQuad extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DomQuad._() {
     throw new UnsupportedError("Not supported");
@@ -11366,7 +11405,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("ClientRectList,DOMRectList")
-class DomRectList extends Interceptor
+class DomRectList extends JavaScriptObject
     with ListMixin<Rectangle>, ImmutableListMixin<Rectangle>
     implements List<Rectangle>, JavaScriptIndexingBehavior<Rectangle> {
   // To suppress missing implicit constructor warnings.
@@ -11426,7 +11465,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DOMRectReadOnly")
-class DomRectReadOnly extends Interceptor implements Rectangle {
+class DomRectReadOnly extends JavaScriptObject implements Rectangle {
   // NOTE! All code below should be common with RectangleBase.
   String toString() {
     return 'Rectangle ($left, $top) $width x $height';
@@ -11616,7 +11655,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DOMStringList")
-class DomStringList extends Interceptor
+class DomStringList extends JavaScriptObject
     with ListMixin<String>, ImmutableListMixin<String>
     implements List<String>, JavaScriptIndexingBehavior<String> {
   // To suppress missing implicit constructor warnings.
@@ -11676,7 +11715,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DOMStringMap")
-class DomStringMap extends Interceptor {
+class DomStringMap extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DomStringMap._() {
     throw new UnsupportedError("Not supported");
@@ -11693,7 +11732,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DOMTokenList")
-class DomTokenList extends Interceptor {
+class DomTokenList extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DomTokenList._() {
     throw new UnsupportedError("Not supported");
@@ -15317,8 +15356,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-@Native("Entry")
-class Entry extends Interceptor {
+@Native("Entry,webkitFileSystemEntry,FileSystemEntry")
+class Entry extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Entry._() {
     throw new UnsupportedError("Not supported");
@@ -15376,6 +15415,8 @@
     var completer = new Completer<Entry>();
     _getParent((value) {
       applyExtension('Entry', value);
+      applyExtension('webkitFileSystemEntry', value);
+      applyExtension('FileSystemEntry', value);
       completer.complete(value);
     }, (error) {
       completer.completeError(error);
@@ -15474,7 +15515,7 @@
 // WARNING: Do not edit - generated code.
 
 @Native("Event,InputEvent,SubmitEvent")
-class Event extends Interceptor {
+class Event extends JavaScriptObject {
   // In JS, canBubble and cancelable are technically required parameters to
   // init*Event. In practice, though, if they aren't provided they simply
   // default to false (since that's Boolean(undefined)).
@@ -15781,7 +15822,7 @@
  * for compile-time type checks and a more concise API.
  */
 @Native("EventTarget")
-class EventTarget extends Interceptor {
+class EventTarget extends JavaScriptObject {
   // Custom element created callback.
   EventTarget._created();
 
@@ -15881,7 +15922,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("External")
-class External extends Interceptor {
+class External extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory External._() {
     throw new UnsupportedError("Not supported");
@@ -15896,7 +15937,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("FaceDetector")
-class FaceDetector extends Interceptor {
+class FaceDetector extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory FaceDetector._() {
     throw new UnsupportedError("Not supported");
@@ -16076,7 +16117,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-@Native("FileEntry")
+@Native("FileEntry,webkitFileSystemFileEntry,FileSystemFileEntry")
 class FileEntry extends Entry {
   // To suppress missing implicit constructor warnings.
   factory FileEntry._() {
@@ -16120,7 +16161,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("FileList")
-class FileList extends Interceptor
+class FileList extends JavaScriptObject
     with ListMixin<File>, ImmutableListMixin<File>
     implements List<File>, JavaScriptIndexingBehavior<File> {
   // To suppress missing implicit constructor warnings.
@@ -16295,8 +16336,8 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @SupportedBrowser(SupportedBrowser.CHROME)
-@Native("DOMFileSystem")
-class FileSystem extends Interceptor {
+@Native("DOMFileSystem,WebKitFileSystem,webkitFileSystem,FileSystem")
+class FileSystem extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory FileSystem._() {
     throw new UnsupportedError("Not supported");
@@ -16462,7 +16503,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("FontFace")
-class FontFace extends Interceptor {
+class FontFace extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory FontFace._() {
     throw new UnsupportedError("Not supported");
@@ -16595,7 +16636,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("FontFaceSource")
-class FontFaceSource extends Interceptor {
+class FontFaceSource extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory FontFaceSource._() {
     throw new UnsupportedError("Not supported");
@@ -16636,7 +16677,7 @@
 @SupportedBrowser(SupportedBrowser.IE, '10')
 @SupportedBrowser(SupportedBrowser.SAFARI)
 @Native("FormData")
-class FormData extends Interceptor {
+class FormData extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory FormData._() {
     throw new UnsupportedError("Not supported");
@@ -16770,7 +16811,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Gamepad")
-class Gamepad extends Interceptor {
+class Gamepad extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Gamepad._() {
     throw new UnsupportedError("Not supported");
@@ -16803,7 +16844,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("GamepadButton")
-class GamepadButton extends Interceptor {
+class GamepadButton extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory GamepadButton._() {
     throw new UnsupportedError("Not supported");
@@ -16845,7 +16886,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("GamepadPose")
-class GamepadPose extends Interceptor {
+class GamepadPose extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory GamepadPose._() {
     throw new UnsupportedError("Not supported");
@@ -16873,7 +16914,7 @@
 
 @Unstable()
 @Native("Geolocation")
-class Geolocation extends Interceptor {
+class Geolocation extends JavaScriptObject {
   Future<Geoposition> getCurrentPosition(
       {bool? enableHighAccuracy, Duration? timeout, Duration? maximumAge}) {
     var options = {};
@@ -17035,7 +17076,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Position,GeolocationPosition")
-class Geoposition extends Interceptor {
+class Geoposition extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Geoposition._() {
     throw new UnsupportedError("Not supported");
@@ -17486,7 +17527,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Headers")
-class Headers extends Interceptor {
+class Headers extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Headers._() {
     throw new UnsupportedError("Not supported");
@@ -17559,7 +17600,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("History")
-class History extends Interceptor implements HistoryBase {
+class History extends JavaScriptObject implements HistoryBase {
   /**
    * Checks if the State APIs are supported on the current platform.
    *
@@ -17633,7 +17674,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("HTMLCollection")
-class HtmlCollection extends Interceptor
+class HtmlCollection extends JavaScriptObject
     with ListMixin<Node>, ImmutableListMixin<Node>
     implements List<Node>, JavaScriptIndexingBehavior<Node> {
   // To suppress missing implicit constructor warnings.
@@ -17891,7 +17932,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("HTMLHyperlinkElementUtils")
-class HtmlHyperlinkElementUtils extends Interceptor {
+class HtmlHyperlinkElementUtils extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory HtmlHyperlinkElementUtils._() {
     throw new UnsupportedError("Not supported");
@@ -18815,7 +18856,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("IdleDeadline")
-class IdleDeadline extends Interceptor {
+class IdleDeadline extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory IdleDeadline._() {
     throw new UnsupportedError("Not supported");
@@ -18837,7 +18878,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("ImageBitmap")
-class ImageBitmap extends Interceptor {
+class ImageBitmap extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ImageBitmap._() {
     throw new UnsupportedError("Not supported");
@@ -18854,7 +18895,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("ImageBitmapRenderingContext")
-class ImageBitmapRenderingContext extends Interceptor {
+class ImageBitmapRenderingContext extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ImageBitmapRenderingContext._() {
     throw new UnsupportedError("Not supported");
@@ -18869,7 +18910,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("ImageCapture")
-class ImageCapture extends Interceptor {
+class ImageCapture extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ImageCapture._() {
     throw new UnsupportedError("Not supported");
@@ -18912,7 +18953,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("ImageData")
-class ImageData extends Interceptor {
+class ImageData extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ImageData._() {
     throw new UnsupportedError("Not supported");
@@ -19033,7 +19074,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("InputDeviceCapabilities")
-class InputDeviceCapabilities extends Interceptor {
+class InputDeviceCapabilities extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory InputDeviceCapabilities._() {
     throw new UnsupportedError("Not supported");
@@ -19889,7 +19930,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("IntersectionObserver")
-class IntersectionObserver extends Interceptor {
+class IntersectionObserver extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory IntersectionObserver._() {
     throw new UnsupportedError("Not supported");
@@ -19940,7 +19981,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("IntersectionObserverEntry")
-class IntersectionObserverEntry extends Interceptor {
+class IntersectionObserverEntry extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory IntersectionObserverEntry._() {
     throw new UnsupportedError("Not supported");
@@ -20356,7 +20397,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Location")
-class Location extends Interceptor implements LocationBase {
+class Location extends JavaScriptObject implements LocationBase {
   // To suppress missing implicit constructor warnings.
   factory Location._() {
     throw new UnsupportedError("Not supported");
@@ -20481,7 +20522,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MediaCapabilities")
-class MediaCapabilities extends Interceptor {
+class MediaCapabilities extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MediaCapabilities._() {
     throw new UnsupportedError("Not supported");
@@ -20510,7 +20551,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MediaCapabilitiesInfo")
-class MediaCapabilitiesInfo extends Interceptor {
+class MediaCapabilitiesInfo extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MediaCapabilitiesInfo._() {
     throw new UnsupportedError("Not supported");
@@ -20527,7 +20568,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MediaDeviceInfo")
-class MediaDeviceInfo extends Interceptor {
+class MediaDeviceInfo extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MediaDeviceInfo._() {
     throw new UnsupportedError("Not supported");
@@ -20764,7 +20805,7 @@
 
 @Unstable()
 @Native("MediaError")
-class MediaError extends Interceptor {
+class MediaError extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MediaError._() {
     throw new UnsupportedError("Not supported");
@@ -20850,7 +20891,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MediaKeyStatusMap")
-class MediaKeyStatusMap extends Interceptor {
+class MediaKeyStatusMap extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MediaKeyStatusMap._() {
     throw new UnsupportedError("Not supported");
@@ -20867,7 +20908,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MediaKeySystemAccess")
-class MediaKeySystemAccess extends Interceptor {
+class MediaKeySystemAccess extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MediaKeySystemAccess._() {
     throw new UnsupportedError("Not supported");
@@ -20890,7 +20931,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MediaKeys")
-class MediaKeys extends Interceptor {
+class MediaKeys extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MediaKeys._() {
     throw new UnsupportedError("Not supported");
@@ -20911,7 +20952,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MediaKeysPolicy")
-class MediaKeysPolicy extends Interceptor {
+class MediaKeysPolicy extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MediaKeysPolicy._() {
     throw new UnsupportedError("Not supported");
@@ -20932,7 +20973,7 @@
 
 @Unstable()
 @Native("MediaList")
-class MediaList extends Interceptor {
+class MediaList extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MediaList._() {
     throw new UnsupportedError("Not supported");
@@ -20955,7 +20996,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MediaMetadata")
-class MediaMetadata extends Interceptor {
+class MediaMetadata extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MediaMetadata._() {
     throw new UnsupportedError("Not supported");
@@ -21104,7 +21145,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MediaSession")
-class MediaSession extends Interceptor {
+class MediaSession extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MediaSession._() {
     throw new UnsupportedError("Not supported");
@@ -21133,7 +21174,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MediaSettingsRange")
-class MediaSettingsRange extends Interceptor {
+class MediaSettingsRange extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MediaSettingsRange._() {
     throw new UnsupportedError("Not supported");
@@ -21442,7 +21483,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MemoryInfo")
-class MemoryInfo extends Interceptor {
+class MemoryInfo extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MemoryInfo._() {
     throw new UnsupportedError("Not supported");
@@ -21500,7 +21541,7 @@
 
 @Unstable()
 @Native("MessageChannel")
-class MessageChannel extends Interceptor {
+class MessageChannel extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MessageChannel._() {
     throw new UnsupportedError("Not supported");
@@ -21713,7 +21754,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Metadata")
-class Metadata extends Interceptor {
+class Metadata extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Metadata._() {
     throw new UnsupportedError("Not supported");
@@ -21863,7 +21904,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MIDIInputMap")
-class MidiInputMap extends Interceptor with MapMixin<String, dynamic> {
+class MidiInputMap extends JavaScriptObject with MapMixin<String, dynamic> {
   // To suppress missing implicit constructor warnings.
   factory MidiInputMap._() {
     throw new UnsupportedError("Not supported");
@@ -21969,7 +22010,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MIDIOutputMap")
-class MidiOutputMap extends Interceptor with MapMixin<String, dynamic> {
+class MidiOutputMap extends JavaScriptObject with MapMixin<String, dynamic> {
   // To suppress missing implicit constructor warnings.
   factory MidiOutputMap._() {
     throw new UnsupportedError("Not supported");
@@ -22066,7 +22107,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MimeType")
-class MimeType extends Interceptor {
+class MimeType extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MimeType._() {
     throw new UnsupportedError("Not supported");
@@ -22085,7 +22126,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MimeTypeArray")
-class MimeTypeArray extends Interceptor
+class MimeTypeArray extends JavaScriptObject
     with ListMixin<MimeType>, ImmutableListMixin<MimeType>
     implements List<MimeType>, JavaScriptIndexingBehavior<MimeType> {
   // To suppress missing implicit constructor warnings.
@@ -22450,7 +22491,7 @@
 @SupportedBrowser(SupportedBrowser.FIREFOX)
 @SupportedBrowser(SupportedBrowser.SAFARI)
 @Native("MutationObserver,WebKitMutationObserver")
-class MutationObserver extends Interceptor {
+class MutationObserver extends JavaScriptObject {
   void disconnect() native;
 
   void _observe(Node target, [Map? options]) {
@@ -22555,7 +22596,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MutationRecord")
-class MutationRecord extends Interceptor {
+class MutationRecord extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory MutationRecord._() {
     throw new UnsupportedError("Not supported");
@@ -22588,7 +22629,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("NavigationPreloadManager")
-class NavigationPreloadManager extends Interceptor {
+class NavigationPreloadManager extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory NavigationPreloadManager._() {
     throw new UnsupportedError("Not supported");
@@ -22861,7 +22902,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("NavigatorAutomationInformation")
-class NavigatorAutomationInformation extends Interceptor {
+class NavigatorAutomationInformation extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory NavigatorAutomationInformation._() {
     throw new UnsupportedError("Not supported");
@@ -22874,7 +22915,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("NavigatorConcurrentHardware")
-class NavigatorConcurrentHardware extends Interceptor {
+class NavigatorConcurrentHardware extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory NavigatorConcurrentHardware._() {
     throw new UnsupportedError("Not supported");
@@ -22887,7 +22928,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("NavigatorCookies")
-class NavigatorCookies extends Interceptor {
+class NavigatorCookies extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory NavigatorCookies._() {
     throw new UnsupportedError("Not supported");
@@ -22899,7 +22940,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-abstract class NavigatorID extends Interceptor {
+abstract class NavigatorID extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory NavigatorID._() {
     throw new UnsupportedError("Not supported");
@@ -22923,7 +22964,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-abstract class NavigatorLanguage extends Interceptor {
+abstract class NavigatorLanguage extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory NavigatorLanguage._() {
     throw new UnsupportedError("Not supported");
@@ -22937,7 +22978,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-abstract class NavigatorOnLine extends Interceptor {
+abstract class NavigatorOnLine extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory NavigatorOnLine._() {
     throw new UnsupportedError("Not supported");
@@ -22950,7 +22991,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("NavigatorUserMediaError")
-class NavigatorUserMediaError extends Interceptor {
+class NavigatorUserMediaError extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory NavigatorUserMediaError._() {
     throw new UnsupportedError("Not supported");
@@ -23546,7 +23587,7 @@
 
 @Unstable()
 @Native("NodeFilter")
-class NodeFilter extends Interceptor {
+class NodeFilter extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory NodeFilter._() {
     throw new UnsupportedError("Not supported");
@@ -23580,7 +23621,7 @@
 
 @Unstable()
 @Native("NodeIterator")
-class NodeIterator extends Interceptor {
+class NodeIterator extends JavaScriptObject {
   factory NodeIterator(Node root, int whatToShow) {
     return document._createNodeIterator(root, whatToShow, null);
   }
@@ -23608,7 +23649,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("NodeList,RadioNodeList")
-class NodeList extends Interceptor
+class NodeList extends JavaScriptObject
     with ListMixin<Node>, ImmutableListMixin<Node>
     implements List<Node>, JavaScriptIndexingBehavior<Node> {
   // To suppress missing implicit constructor warnings.
@@ -23669,7 +23710,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("NonDocumentTypeChildNode")
-class NonDocumentTypeChildNode extends Interceptor {
+class NonDocumentTypeChildNode extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory NonDocumentTypeChildNode._() {
     throw new UnsupportedError("Not supported");
@@ -23684,7 +23725,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("NonElementParentNode")
-class NonElementParentNode extends Interceptor {
+class NonElementParentNode extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory NonElementParentNode._() {
     throw new UnsupportedError("Not supported");
@@ -23697,7 +23738,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("NoncedElement")
-class NoncedElement extends Interceptor {
+class NoncedElement extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory NoncedElement._() {
     throw new UnsupportedError("Not supported");
@@ -24038,7 +24079,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("OffscreenCanvasRenderingContext2D")
-class OffscreenCanvasRenderingContext2D extends Interceptor
+class OffscreenCanvasRenderingContext2D extends JavaScriptObject
     implements _CanvasPath {
   // To suppress missing implicit constructor warnings.
   factory OffscreenCanvasRenderingContext2D._() {
@@ -24482,7 +24523,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("OverconstrainedError")
-class OverconstrainedError extends Interceptor {
+class OverconstrainedError extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory OverconstrainedError._() {
     throw new UnsupportedError("Not supported");
@@ -24536,7 +24577,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PaintRenderingContext2D")
-class PaintRenderingContext2D extends Interceptor implements _CanvasPath {
+class PaintRenderingContext2D extends JavaScriptObject implements _CanvasPath {
   // To suppress missing implicit constructor warnings.
   factory PaintRenderingContext2D._() {
     throw new UnsupportedError("Not supported");
@@ -24693,7 +24734,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PaintSize")
-class PaintSize extends Interceptor {
+class PaintSize extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PaintSize._() {
     throw new UnsupportedError("Not supported");
@@ -24777,7 +24818,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-abstract class ParentNode extends Interceptor {
+abstract class ParentNode extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ParentNode._() {
     throw new UnsupportedError("Not supported");
@@ -24847,7 +24888,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Path2D")
-class Path2D extends Interceptor implements _CanvasPath {
+class Path2D extends JavaScriptObject implements _CanvasPath {
   // To suppress missing implicit constructor warnings.
   factory Path2D._() {
     throw new UnsupportedError("Not supported");
@@ -24901,7 +24942,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PaymentAddress")
-class PaymentAddress extends Interceptor {
+class PaymentAddress extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PaymentAddress._() {
     throw new UnsupportedError("Not supported");
@@ -24934,7 +24975,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PaymentInstruments")
-class PaymentInstruments extends Interceptor {
+class PaymentInstruments extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PaymentInstruments._() {
     throw new UnsupportedError("Not supported");
@@ -24965,7 +25006,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PaymentManager")
-class PaymentManager extends Interceptor {
+class PaymentManager extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PaymentManager._() {
     throw new UnsupportedError("Not supported");
@@ -25101,7 +25142,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PaymentResponse")
-class PaymentResponse extends Interceptor {
+class PaymentResponse extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PaymentResponse._() {
     throw new UnsupportedError("Not supported");
@@ -25177,7 +25218,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PerformanceEntry")
-class PerformanceEntry extends Interceptor {
+class PerformanceEntry extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PerformanceEntry._() {
     throw new UnsupportedError("Not supported");
@@ -25232,7 +25273,7 @@
 
 @Unstable()
 @Native("PerformanceNavigation")
-class PerformanceNavigation extends Interceptor {
+class PerformanceNavigation extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PerformanceNavigation._() {
     throw new UnsupportedError("Not supported");
@@ -25286,7 +25327,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PerformanceObserver")
-class PerformanceObserver extends Interceptor {
+class PerformanceObserver extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PerformanceObserver._() {
     throw new UnsupportedError("Not supported");
@@ -25323,7 +25364,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PerformanceObserverEntryList")
-class PerformanceObserverEntryList extends Interceptor {
+class PerformanceObserverEntryList extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PerformanceObserverEntryList._() {
     throw new UnsupportedError("Not supported");
@@ -25399,7 +25440,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PerformanceServerTiming")
-class PerformanceServerTiming extends Interceptor {
+class PerformanceServerTiming extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PerformanceServerTiming._() {
     throw new UnsupportedError("Not supported");
@@ -25417,7 +25458,7 @@
 
 @Unstable()
 @Native("PerformanceTiming")
-class PerformanceTiming extends Interceptor {
+class PerformanceTiming extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PerformanceTiming._() {
     throw new UnsupportedError("Not supported");
@@ -25488,7 +25529,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Permissions")
-class Permissions extends Interceptor {
+class Permissions extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Permissions._() {
     throw new UnsupportedError("Not supported");
@@ -25521,7 +25562,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PhotoCapabilities")
-class PhotoCapabilities extends Interceptor {
+class PhotoCapabilities extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PhotoCapabilities._() {
     throw new UnsupportedError("Not supported");
@@ -25557,7 +25598,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Plugin")
-class Plugin extends Interceptor {
+class Plugin extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Plugin._() {
     throw new UnsupportedError("Not supported");
@@ -25580,7 +25621,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PluginArray")
-class PluginArray extends Interceptor
+class PluginArray extends JavaScriptObject
     with ListMixin<Plugin>, ImmutableListMixin<Plugin>
     implements List<Plugin>, JavaScriptIndexingBehavior<Plugin> {
   // To suppress missing implicit constructor warnings.
@@ -25745,7 +25786,7 @@
 
 @Unstable()
 @Native("PositionError,GeolocationPositionError")
-class PositionError extends Interceptor {
+class PositionError extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PositionError._() {
     throw new UnsupportedError("Not supported");
@@ -25797,7 +25838,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Presentation")
-class Presentation extends Interceptor {
+class Presentation extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Presentation._() {
     throw new UnsupportedError("Not supported");
@@ -25924,7 +25965,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PresentationReceiver")
-class PresentationReceiver extends Interceptor {
+class PresentationReceiver extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PresentationReceiver._() {
     throw new UnsupportedError("Not supported");
@@ -26128,7 +26169,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PushManager")
-class PushManager extends Interceptor {
+class PushManager extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PushManager._() {
     throw new UnsupportedError("Not supported");
@@ -26162,7 +26203,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PushMessageData")
-class PushMessageData extends Interceptor {
+class PushMessageData extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PushMessageData._() {
     throw new UnsupportedError("Not supported");
@@ -26181,7 +26222,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PushSubscription")
-class PushSubscription extends Interceptor {
+class PushSubscription extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PushSubscription._() {
     throw new UnsupportedError("Not supported");
@@ -26203,7 +26244,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PushSubscriptionOptions")
-class PushSubscriptionOptions extends Interceptor {
+class PushSubscriptionOptions extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PushSubscriptionOptions._() {
     throw new UnsupportedError("Not supported");
@@ -26269,7 +26310,7 @@
 
 @Unstable()
 @Native("Range")
-class Range extends Interceptor {
+class Range extends JavaScriptObject {
   factory Range() => document.createRange();
 
   factory Range.fromPoint(Point point) =>
@@ -26377,7 +26418,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("RelatedApplication")
-class RelatedApplication extends Interceptor {
+class RelatedApplication extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory RelatedApplication._() {
     throw new UnsupportedError("Not supported");
@@ -26447,7 +26488,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("ReportBody")
-class ReportBody extends Interceptor {
+class ReportBody extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ReportBody._() {
     throw new UnsupportedError("Not supported");
@@ -26458,7 +26499,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("ReportingObserver")
-class ReportingObserver extends Interceptor {
+class ReportingObserver extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ReportingObserver._() {
     throw new UnsupportedError("Not supported");
@@ -26495,7 +26536,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("ResizeObserver")
-class ResizeObserver extends Interceptor {
+class ResizeObserver extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ResizeObserver._() {
     throw new UnsupportedError("Not supported");
@@ -26526,7 +26567,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("ResizeObserverEntry")
-class ResizeObserverEntry extends Interceptor {
+class ResizeObserverEntry extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ResizeObserverEntry._() {
     throw new UnsupportedError("Not supported");
@@ -26541,7 +26582,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("RTCCertificate")
-class RtcCertificate extends Interceptor {
+class RtcCertificate extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory RtcCertificate._() {
     throw new UnsupportedError("Not supported");
@@ -26744,7 +26785,7 @@
 
 @SupportedBrowser(SupportedBrowser.CHROME)
 @Native("RTCIceCandidate,mozRTCIceCandidate")
-class RtcIceCandidate extends Interceptor {
+class RtcIceCandidate extends JavaScriptObject {
   factory RtcIceCandidate(Map dictionary) {
     var constructorName = JS('', 'window[#]', 'RTCIceCandidate');
     return JS('RtcIceCandidate', 'new #(#)', constructorName,
@@ -26772,7 +26813,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("RTCLegacyStatsReport")
-class RtcLegacyStatsReport extends Interceptor {
+class RtcLegacyStatsReport extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory RtcLegacyStatsReport._() {
     throw new UnsupportedError("Not supported");
@@ -27106,7 +27147,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("RTCRtpContributingSource")
-class RtcRtpContributingSource extends Interceptor {
+class RtcRtpContributingSource extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory RtcRtpContributingSource._() {
     throw new UnsupportedError("Not supported");
@@ -27121,7 +27162,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("RTCRtpReceiver")
-class RtcRtpReceiver extends Interceptor {
+class RtcRtpReceiver extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory RtcRtpReceiver._() {
     throw new UnsupportedError("Not supported");
@@ -27136,7 +27177,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("RTCRtpSender")
-class RtcRtpSender extends Interceptor {
+class RtcRtpSender extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory RtcRtpSender._() {
     throw new UnsupportedError("Not supported");
@@ -27150,7 +27191,7 @@
 
 @SupportedBrowser(SupportedBrowser.CHROME)
 @Native("RTCSessionDescription,mozRTCSessionDescription")
-class RtcSessionDescription extends Interceptor {
+class RtcSessionDescription extends JavaScriptObject {
   factory RtcSessionDescription(Map dictionary) {
     var constructorName = JS('', 'window[#]', 'RTCSessionDescription');
     return JS('RtcSessionDescription', 'new #(#)', constructorName,
@@ -27174,7 +27215,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("RTCStatsReport")
-class RtcStatsReport extends Interceptor with MapMixin<String, dynamic> {
+class RtcStatsReport extends JavaScriptObject with MapMixin<String, dynamic> {
   // To suppress missing implicit constructor warnings.
   factory RtcStatsReport._() {
     throw new UnsupportedError("Not supported");
@@ -27242,7 +27283,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("RTCStatsResponse")
-class RtcStatsResponse extends Interceptor {
+class RtcStatsResponse extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory RtcStatsResponse._() {
     throw new UnsupportedError("Not supported");
@@ -27281,7 +27322,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Screen")
-class Screen extends Interceptor {
+class Screen extends JavaScriptObject {
   Rectangle get available =>
       new Rectangle(_availLeft!, _availTop!, _availWidth!, _availHeight!);
   // To suppress missing implicit constructor warnings.
@@ -27400,7 +27441,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("ScrollState")
-class ScrollState extends Interceptor {
+class ScrollState extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ScrollState._() {
     throw new UnsupportedError("Not supported");
@@ -27645,7 +27686,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Selection")
-class Selection extends Interceptor {
+class Selection extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Selection._() {
     throw new UnsupportedError("Not supported");
@@ -28050,7 +28091,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("SharedArrayBuffer")
-class SharedArrayBuffer extends Interceptor {
+class SharedArrayBuffer extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory SharedArrayBuffer._() {
     throw new UnsupportedError("Not supported");
@@ -28370,7 +28411,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("SpeechGrammar")
-class SpeechGrammar extends Interceptor {
+class SpeechGrammar extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory SpeechGrammar._() {
     throw new UnsupportedError("Not supported");
@@ -28395,7 +28436,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("SpeechGrammarList")
-class SpeechGrammarList extends Interceptor
+class SpeechGrammarList extends JavaScriptObject
     with ListMixin<SpeechGrammar>, ImmutableListMixin<SpeechGrammar>
     implements List<SpeechGrammar>, JavaScriptIndexingBehavior<SpeechGrammar> {
   // To suppress missing implicit constructor warnings.
@@ -28649,7 +28690,7 @@
 
 @SupportedBrowser(SupportedBrowser.CHROME, '25')
 @Native("SpeechRecognitionAlternative")
-class SpeechRecognitionAlternative extends Interceptor {
+class SpeechRecognitionAlternative extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory SpeechRecognitionAlternative._() {
     throw new UnsupportedError("Not supported");
@@ -28733,7 +28774,7 @@
 
 @SupportedBrowser(SupportedBrowser.CHROME, '25')
 @Native("SpeechRecognitionResult")
-class SpeechRecognitionResult extends Interceptor {
+class SpeechRecognitionResult extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory SpeechRecognitionResult._() {
     throw new UnsupportedError("Not supported");
@@ -28933,7 +28974,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("SpeechSynthesisVoice")
-class SpeechSynthesisVoice extends Interceptor {
+class SpeechSynthesisVoice extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory SpeechSynthesisVoice._() {
     throw new UnsupportedError("Not supported");
@@ -28956,7 +28997,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("StaticRange")
-class StaticRange extends Interceptor {
+class StaticRange extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory StaticRange._() {
     throw new UnsupportedError("Not supported");
@@ -28998,7 +29039,7 @@
  */
 @Unstable()
 @Native("Storage")
-class Storage extends Interceptor with MapMixin<String, String> {
+class Storage extends JavaScriptObject with MapMixin<String, String> {
   void addAll(Map<String, String> other) {
     other.forEach((k, v) {
       this[k] = v;
@@ -29146,7 +29187,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("StorageManager")
-class StorageManager extends Interceptor {
+class StorageManager extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory StorageManager._() {
     throw new UnsupportedError("Not supported");
@@ -29217,7 +29258,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("StyleMedia")
-class StyleMedia extends Interceptor {
+class StyleMedia extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory StyleMedia._() {
     throw new UnsupportedError("Not supported");
@@ -29249,7 +29290,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("StylePropertyMapReadonly")
-class StylePropertyMapReadonly extends Interceptor {
+class StylePropertyMapReadonly extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory StylePropertyMapReadonly._() {
     throw new UnsupportedError("Not supported");
@@ -29268,7 +29309,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("StyleSheet")
-class StyleSheet extends Interceptor {
+class StyleSheet extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory StyleSheet._() {
     throw new UnsupportedError("Not supported");
@@ -29317,7 +29358,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("SyncManager")
-class SyncManager extends Interceptor {
+class SyncManager extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory SyncManager._() {
     throw new UnsupportedError("Not supported");
@@ -29867,7 +29908,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("TextDetector")
-class TextDetector extends Interceptor {
+class TextDetector extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory TextDetector._() {
     throw new UnsupportedError("Not supported");
@@ -29918,7 +29959,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("TextMetrics")
-class TextMetrics extends Interceptor {
+class TextMetrics extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory TextMetrics._() {
     throw new UnsupportedError("Not supported");
@@ -30049,7 +30090,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("TextTrackCueList")
-class TextTrackCueList extends Interceptor
+class TextTrackCueList extends JavaScriptObject
     with ListMixin<TextTrackCue>, ImmutableListMixin<TextTrackCue>
     implements List<TextTrackCue>, JavaScriptIndexingBehavior<TextTrackCue> {
   // To suppress missing implicit constructor warnings.
@@ -30212,7 +30253,7 @@
 
 @Unstable()
 @Native("TimeRanges")
-class TimeRanges extends Interceptor {
+class TimeRanges extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory TimeRanges._() {
     throw new UnsupportedError("Not supported");
@@ -30259,7 +30300,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Touch")
-class Touch extends Interceptor {
+class Touch extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Touch._() {
     throw new UnsupportedError("Not supported");
@@ -30389,7 +30430,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("TouchList")
-class TouchList extends Interceptor
+class TouchList extends JavaScriptObject
     with ListMixin<Touch>, ImmutableListMixin<Touch>
     implements List<Touch>, JavaScriptIndexingBehavior<Touch> {
   // To suppress missing implicit constructor warnings.
@@ -30452,7 +30493,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("TrackDefault")
-class TrackDefault extends Interceptor {
+class TrackDefault extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory TrackDefault._() {
     throw new UnsupportedError("Not supported");
@@ -30496,7 +30537,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("TrackDefaultList")
-class TrackDefaultList extends Interceptor {
+class TrackDefaultList extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory TrackDefaultList._() {
     throw new UnsupportedError("Not supported");
@@ -30638,7 +30679,7 @@
 
 @Unstable()
 @Native("TreeWalker")
-class TreeWalker extends Interceptor {
+class TreeWalker extends JavaScriptObject {
   factory TreeWalker(Node root, int whatToShow) {
     return document._createTreeWalker(root, whatToShow, null);
   }
@@ -30676,7 +30717,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("TrustedHTML")
-class TrustedHtml extends Interceptor {
+class TrustedHtml extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory TrustedHtml._() {
     throw new UnsupportedError("Not supported");
@@ -30691,7 +30732,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("TrustedScriptURL")
-class TrustedScriptUrl extends Interceptor {
+class TrustedScriptUrl extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory TrustedScriptUrl._() {
     throw new UnsupportedError("Not supported");
@@ -30704,7 +30745,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("TrustedURL")
-class TrustedUrl extends Interceptor {
+class TrustedUrl extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory TrustedUrl._() {
     throw new UnsupportedError("Not supported");
@@ -30798,7 +30839,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("UnderlyingSourceBase")
-class UnderlyingSourceBase extends Interceptor {
+class UnderlyingSourceBase extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory UnderlyingSourceBase._() {
     throw new UnsupportedError("Not supported");
@@ -30838,7 +30879,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("URL")
-class Url extends Interceptor {
+class Url extends JavaScriptObject {
   static String createObjectUrl(blob_OR_source_OR_stream) => JS(
       'String',
       '(self.URL || self.webkitURL).createObjectURL(#)',
@@ -30912,7 +30953,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("URLSearchParams")
-class UrlSearchParams extends Interceptor {
+class UrlSearchParams extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory UrlSearchParams._() {
     throw new UnsupportedError("Not supported");
@@ -30947,7 +30988,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-abstract class UrlUtilsReadOnly extends Interceptor {
+abstract class UrlUtilsReadOnly extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory UrlUtilsReadOnly._() {
     throw new UnsupportedError("Not supported");
@@ -30989,7 +31030,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("VRCoordinateSystem")
-class VRCoordinateSystem extends Interceptor {
+class VRCoordinateSystem extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory VRCoordinateSystem._() {
     throw new UnsupportedError("Not supported");
@@ -31099,7 +31140,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("VRDisplayCapabilities")
-class VRDisplayCapabilities extends Interceptor {
+class VRDisplayCapabilities extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory VRDisplayCapabilities._() {
     throw new UnsupportedError("Not supported");
@@ -31145,7 +31186,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("VREyeParameters")
-class VREyeParameters extends Interceptor {
+class VREyeParameters extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory VREyeParameters._() {
     throw new UnsupportedError("Not supported");
@@ -31162,7 +31203,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("VRFrameData")
-class VRFrameData extends Interceptor {
+class VRFrameData extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory VRFrameData._() {
     throw new UnsupportedError("Not supported");
@@ -31203,7 +31244,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("VRPose")
-class VRPose extends Interceptor {
+class VRPose extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory VRPose._() {
     throw new UnsupportedError("Not supported");
@@ -31290,7 +31331,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("VRStageBounds")
-class VRStageBounds extends Interceptor {
+class VRStageBounds extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory VRStageBounds._() {
     throw new UnsupportedError("Not supported");
@@ -31303,7 +31344,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("VRStageBoundsPoint")
-class VRStageBoundsPoint extends Interceptor {
+class VRStageBoundsPoint extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory VRStageBoundsPoint._() {
     throw new UnsupportedError("Not supported");
@@ -31318,7 +31359,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("VRStageParameters")
-class VRStageParameters extends Interceptor {
+class VRStageParameters extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory VRStageParameters._() {
     throw new UnsupportedError("Not supported");
@@ -31335,7 +31376,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("ValidityState")
-class ValidityState extends Interceptor {
+class ValidityState extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ValidityState._() {
     throw new UnsupportedError("Not supported");
@@ -31429,7 +31470,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("VideoPlaybackQuality")
-class VideoPlaybackQuality extends Interceptor {
+class VideoPlaybackQuality extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory VideoPlaybackQuality._() {
     throw new UnsupportedError("Not supported");
@@ -31448,7 +31489,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("VideoTrack")
-class VideoTrack extends Interceptor {
+class VideoTrack extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory VideoTrack._() {
     throw new UnsupportedError("Not supported");
@@ -31595,7 +31636,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("VTTRegion")
-class VttRegion extends Interceptor {
+class VttRegion extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory VttRegion._() {
     throw new UnsupportedError("Not supported");
@@ -33338,7 +33379,12 @@
     var completer = new Completer<FileSystem>();
     __requestFileSystem(type, size, (value) {
       applyExtension('DOMFileSystem', value);
+      applyExtension('WebKitFileSystem', value);
+      applyExtension('webkitFileSystem', value);
+      applyExtension('FileSystem', value);
       applyExtension('DirectoryEntry', value.root);
+      applyExtension('webkitFileSystemDirectoryEntry', value.root);
+      applyExtension('FileSystemDirectoryEntry', value.root);
       completer.complete(value);
     }, (error) {
       completer.completeError(error);
@@ -33756,7 +33802,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-abstract class WindowBase64 extends Interceptor {
+abstract class WindowBase64 extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory WindowBase64._() {
     throw new UnsupportedError("Not supported");
@@ -34026,7 +34072,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WorkletAnimation")
-class WorkletAnimation extends Interceptor {
+class WorkletAnimation extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory WorkletAnimation._() {
     throw new UnsupportedError("Not supported");
@@ -34057,7 +34103,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WorkletGlobalScope")
-class WorkletGlobalScope extends Interceptor {
+class WorkletGlobalScope extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory WorkletGlobalScope._() {
     throw new UnsupportedError("Not supported");
@@ -34070,7 +34116,7 @@
 // http://www.w3.org/TR/DOM-Level-3-XPath/xpath.html#XPathEvaluator
 @deprecated // experimental
 @Native("XPathEvaluator")
-class XPathEvaluator extends Interceptor {
+class XPathEvaluator extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory XPathEvaluator._() {
     throw new UnsupportedError("Not supported");
@@ -34098,7 +34144,7 @@
 // http://www.w3.org/TR/DOM-Level-3-XPath/xpath.html#XPathExpression
 @deprecated // experimental
 @Native("XPathExpression")
-class XPathExpression extends Interceptor {
+class XPathExpression extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory XPathExpression._() {
     throw new UnsupportedError("Not supported");
@@ -34113,7 +34159,7 @@
 // http://www.w3.org/TR/DOM-Level-3-XPath/xpath.html#XPathNSResolver
 @deprecated // experimental
 @Native("XPathNSResolver")
-class XPathNSResolver extends Interceptor {
+class XPathNSResolver extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory XPathNSResolver._() {
     throw new UnsupportedError("Not supported");
@@ -34129,7 +34175,7 @@
 // http://www.w3.org/TR/DOM-Level-3-XPath/xpath.html#XPathResult
 @deprecated // experimental
 @Native("XPathResult")
-class XPathResult extends Interceptor {
+class XPathResult extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory XPathResult._() {
     throw new UnsupportedError("Not supported");
@@ -34191,7 +34237,7 @@
 // http://domparsing.spec.whatwg.org/#the-xmlserializer-interface
 @deprecated // stable
 @Native("XMLSerializer")
-class XmlSerializer extends Interceptor {
+class XmlSerializer extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory XmlSerializer._() {
     throw new UnsupportedError("Not supported");
@@ -34214,7 +34260,7 @@
 @SupportedBrowser(SupportedBrowser.SAFARI)
 @deprecated // nonstandard
 @Native("XSLTProcessor")
-class XsltProcessor extends Interceptor {
+class XsltProcessor extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory XsltProcessor._() {
     throw new UnsupportedError("Not supported");
@@ -34274,7 +34320,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Bluetooth")
-abstract class _Bluetooth extends Interceptor {
+abstract class _Bluetooth extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _Bluetooth._() {
     throw new UnsupportedError("Not supported");
@@ -34285,7 +34331,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("BluetoothCharacteristicProperties")
-abstract class _BluetoothCharacteristicProperties extends Interceptor {
+abstract class _BluetoothCharacteristicProperties extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _BluetoothCharacteristicProperties._() {
     throw new UnsupportedError("Not supported");
@@ -34318,7 +34364,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("BluetoothRemoteGATTServer")
-abstract class _BluetoothRemoteGATTServer extends Interceptor {
+abstract class _BluetoothRemoteGATTServer extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _BluetoothRemoteGATTServer._() {
     throw new UnsupportedError("Not supported");
@@ -34329,7 +34375,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("BluetoothRemoteGATTService")
-abstract class _BluetoothRemoteGATTService extends Interceptor {
+abstract class _BluetoothRemoteGATTService extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _BluetoothRemoteGATTService._() {
     throw new UnsupportedError("Not supported");
@@ -34340,7 +34386,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("BluetoothUUID")
-abstract class _BluetoothUUID extends Interceptor {
+abstract class _BluetoothUUID extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _BluetoothUUID._() {
     throw new UnsupportedError("Not supported");
@@ -34351,7 +34397,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("BudgetService")
-class _BudgetService extends Interceptor {
+class _BudgetService extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _BudgetService._() {
     throw new UnsupportedError("Not supported");
@@ -34371,7 +34417,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Cache")
-abstract class _Cache extends Interceptor {
+abstract class _Cache extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _Cache._() {
     throw new UnsupportedError("Not supported");
@@ -34381,7 +34427,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-abstract class _CanvasPath extends Interceptor {
+abstract class _CanvasPath extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _CanvasPath._() {
     throw new UnsupportedError("Not supported");
@@ -34415,7 +34461,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("CSSRuleList")
-class _CssRuleList extends Interceptor
+class _CssRuleList extends JavaScriptObject
     with ListMixin<CssRule>, ImmutableListMixin<CssRule>
     implements List<CssRule>, JavaScriptIndexingBehavior<CssRule> {
   // To suppress missing implicit constructor warnings.
@@ -34476,7 +34522,7 @@
 
 @SupportedBrowser(SupportedBrowser.CHROME)
 @Native("DOMFileSystemSync")
-abstract class _DOMFileSystemSync extends Interceptor {
+abstract class _DOMFileSystemSync extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _DOMFileSystemSync._() {
     throw new UnsupportedError("Not supported");
@@ -34498,7 +34544,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("DirectoryReaderSync")
-abstract class _DirectoryReaderSync extends Interceptor {
+abstract class _DirectoryReaderSync extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _DirectoryReaderSync._() {
     throw new UnsupportedError("Not supported");
@@ -34683,7 +34729,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("EntrySync")
-abstract class _EntrySync extends Interceptor {
+abstract class _EntrySync extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _EntrySync._() {
     throw new UnsupportedError("Not supported");
@@ -34705,7 +34751,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("FileReaderSync")
-abstract class _FileReaderSync extends Interceptor {
+abstract class _FileReaderSync extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _FileReaderSync._() {
     throw new UnsupportedError("Not supported");
@@ -34722,7 +34768,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("FileWriterSync")
-abstract class _FileWriterSync extends Interceptor {
+abstract class _FileWriterSync extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _FileWriterSync._() {
     throw new UnsupportedError("Not supported");
@@ -34733,7 +34779,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("GamepadList")
-class _GamepadList extends Interceptor
+class _GamepadList extends JavaScriptObject
     with ListMixin<Gamepad?>, ImmutableListMixin<Gamepad?>
     implements List<Gamepad?>, JavaScriptIndexingBehavior<Gamepad?> {
   // To suppress missing implicit constructor warnings.
@@ -34795,7 +34841,7 @@
 // http://www.whatwg.org/specs/web-apps/current-work/multipage/obsolete.html#dom-document-all
 @deprecated // deprecated
 @Native("HTMLAllCollection")
-abstract class _HTMLAllCollection extends Interceptor {
+abstract class _HTMLAllCollection extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _HTMLAllCollection._() {
     throw new UnsupportedError("Not supported");
@@ -34906,7 +34952,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Mojo")
-abstract class _Mojo extends Interceptor {
+abstract class _Mojo extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _Mojo._() {
     throw new UnsupportedError("Not supported");
@@ -34917,7 +34963,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MojoHandle")
-abstract class _MojoHandle extends Interceptor {
+abstract class _MojoHandle extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _MojoHandle._() {
     throw new UnsupportedError("Not supported");
@@ -34981,7 +35027,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("MojoWatcher")
-abstract class _MojoWatcher extends Interceptor {
+abstract class _MojoWatcher extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _MojoWatcher._() {
     throw new UnsupportedError("Not supported");
@@ -34992,7 +35038,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("NFC")
-abstract class _NFC extends Interceptor {
+abstract class _NFC extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _NFC._() {
     throw new UnsupportedError("Not supported");
@@ -35005,7 +35051,7 @@
 // http://dom.spec.whatwg.org/#namednodemap
 @deprecated // deprecated
 @Native("NamedNodeMap,MozNamedAttrMap")
-class _NamedNodeMap extends Interceptor
+class _NamedNodeMap extends JavaScriptObject
     with ListMixin<Node>, ImmutableListMixin<Node>
     implements List<Node>, JavaScriptIndexingBehavior<Node> {
   // To suppress missing implicit constructor warnings.
@@ -35078,7 +35124,7 @@
 
 @deprecated // nonstandard
 @Native("PagePopupController")
-abstract class _PagePopupController extends Interceptor {
+abstract class _PagePopupController extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _PagePopupController._() {
     throw new UnsupportedError("Not supported");
@@ -35097,7 +35143,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Report")
-class _Report extends Interceptor {
+class _Report extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _Report._() {
     throw new UnsupportedError("Not supported");
@@ -35195,7 +35241,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("SpeechRecognitionResultList")
-class _SpeechRecognitionResultList extends Interceptor
+class _SpeechRecognitionResultList extends JavaScriptObject
     with
         ListMixin<SpeechRecognitionResult>,
         ImmutableListMixin<SpeechRecognitionResult>
@@ -35259,7 +35305,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("StyleSheetList")
-class _StyleSheetList extends Interceptor
+class _StyleSheetList extends JavaScriptObject
     with ListMixin<StyleSheet>, ImmutableListMixin<StyleSheet>
     implements List<StyleSheet>, JavaScriptIndexingBehavior<StyleSheet> {
   // To suppress missing implicit constructor warnings.
@@ -35321,7 +35367,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("SubtleCrypto")
-abstract class _SubtleCrypto extends Interceptor {
+abstract class _SubtleCrypto extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _SubtleCrypto._() {
     throw new UnsupportedError("Not supported");
@@ -35343,7 +35389,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("USBAlternateInterface")
-abstract class _USBAlternateInterface extends Interceptor {
+abstract class _USBAlternateInterface extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _USBAlternateInterface._() {
     throw new UnsupportedError("Not supported");
@@ -35362,7 +35408,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("USBConfiguration")
-abstract class _USBConfiguration extends Interceptor {
+abstract class _USBConfiguration extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _USBConfiguration._() {
     throw new UnsupportedError("Not supported");
@@ -35403,7 +35449,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("USBDevice")
-abstract class _USBDevice extends Interceptor {
+abstract class _USBDevice extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _USBDevice._() {
     throw new UnsupportedError("Not supported");
@@ -35414,7 +35460,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("USBEndpoint")
-abstract class _USBEndpoint extends Interceptor {
+abstract class _USBEndpoint extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _USBEndpoint._() {
     throw new UnsupportedError("Not supported");
@@ -35436,7 +35482,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("USBInTransferResult")
-abstract class _USBInTransferResult extends Interceptor {
+abstract class _USBInTransferResult extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _USBInTransferResult._() {
     throw new UnsupportedError("Not supported");
@@ -35458,7 +35504,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("USBInterface")
-abstract class _USBInterface extends Interceptor {
+abstract class _USBInterface extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _USBInterface._() {
     throw new UnsupportedError("Not supported");
@@ -35475,7 +35521,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("USBIsochronousInTransferPacket")
-abstract class _USBIsochronousInTransferPacket extends Interceptor {
+abstract class _USBIsochronousInTransferPacket extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _USBIsochronousInTransferPacket._() {
     throw new UnsupportedError("Not supported");
@@ -35502,7 +35548,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("USBIsochronousInTransferResult")
-abstract class _USBIsochronousInTransferResult extends Interceptor {
+abstract class _USBIsochronousInTransferResult extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _USBIsochronousInTransferResult._() {
     throw new UnsupportedError("Not supported");
@@ -35531,7 +35577,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("USBIsochronousOutTransferPacket")
-abstract class _USBIsochronousOutTransferPacket extends Interceptor {
+abstract class _USBIsochronousOutTransferPacket extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _USBIsochronousOutTransferPacket._() {
     throw new UnsupportedError("Not supported");
@@ -35558,7 +35604,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("USBIsochronousOutTransferResult")
-abstract class _USBIsochronousOutTransferResult extends Interceptor {
+abstract class _USBIsochronousOutTransferResult extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _USBIsochronousOutTransferResult._() {
     throw new UnsupportedError("Not supported");
@@ -35578,7 +35624,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("USBOutTransferResult")
-abstract class _USBOutTransferResult extends Interceptor {
+abstract class _USBOutTransferResult extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _USBOutTransferResult._() {
     throw new UnsupportedError("Not supported");
@@ -35602,7 +35648,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-abstract class _WindowTimers extends Interceptor {
+abstract class _WindowTimers extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _WindowTimers._() {
     throw new UnsupportedError("Not supported");
@@ -35625,7 +35671,8 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WorkerLocation")
-abstract class _WorkerLocation extends Interceptor implements UrlUtilsReadOnly {
+abstract class _WorkerLocation extends JavaScriptObject
+    implements UrlUtilsReadOnly {
   // To suppress missing implicit constructor warnings.
   factory _WorkerLocation._() {
     throw new UnsupportedError("Not supported");
@@ -35658,7 +35705,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("Worklet")
-abstract class _Worklet extends Interceptor {
+abstract class _Worklet extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _Worklet._() {
     throw new UnsupportedError("Not supported");
diff --git a/sdk/lib/html/doc/WORKAROUNDS.md b/sdk/lib/html/doc/WORKAROUNDS.md
index 39a1c06..154c891 100644
--- a/sdk/lib/html/doc/WORKAROUNDS.md
+++ b/sdk/lib/html/doc/WORKAROUNDS.md
@@ -19,14 +19,46 @@
 As mentioned above, there exists stale interfaces. While some of these may be
 fixed in the source code, many might not.
 
-In order to circumvent this, you can use the `js_util` library, like
-`getProperty`, `setProperty`, `callMethod`, and `callConstructor`.
+In order to work around this, you can use the annotation `@staticInterop` from
+`package:js`.
 
 Let’s look at an example. `FileReader` is a `dart:html` interface that is
 missing the API `readAsBinaryString` ([#42834][]). We can work around this by
 doing something like the following:
 
 ```dart
+@JS()
+library workarounds;
+
+import 'dart:html';
+
+import 'package:async_helper/async_minitest.dart';
+import 'package:expect/expect.dart';
+import 'package:js/js.dart';
+
+@JS()
+@staticInterop
+class JSFileReader {}
+
+extension JSFileReaderExtension on JSFileReader {
+  external void readAsBinaryString(Blob blob);
+}
+
+void main() async {
+  var reader = new FileReader();
+  reader.onLoad.listen(expectAsync((event) {
+    String result = reader.result as String;
+    Expect.equals(result, '00000000');
+  }));
+  var jsReader = reader as JSFileReader;
+  jsReader.readAsBinaryString(new Blob(['00000000']));
+}
+```
+
+Alternatively, you can directly use the `js_util` library, using the methods
+`getProperty`, `setProperty`, `callMethod`, and `callConstructor`.
+
+```dart
 import 'dart:html';
 import 'dart:js_util' as js_util;
 
@@ -46,9 +78,37 @@
 }
 ```
 
-In the case where the API is missing a constructor, we can use
-`callConstructor`. For example, instead of using the factory constructor for
-`KeyboardEvent`, we can do the following:
+In the case where the API is missing a constructor, we can define a constructor
+within a `@staticInterop` class. Note that constructors, `external` or
+otherwise, are disallowed in extensions currently. For example:
+
+```dart
+@JS()
+library workarounds;
+
+import 'dart:js_util' as js_util;
+
+import 'package:expect/expect.dart';
+import 'package:js/js.dart';
+
+@JS('KeyboardEvent')
+@staticInterop
+class JSKeyboardEvent {
+  external JSKeyboardEvent(String typeArg, Object keyboardEventInit);
+}
+
+extension JSKeyboardEventExtension on JSKeyboardEvent {
+  external String get key;
+}
+
+void main() {
+  var event = JSKeyboardEvent('KeyboardEvent',
+      js_util.jsify({'key': 'A'}));
+  Expect.equals(event.key, 'A');
+}
+```
+
+or with `js_util`'s `callConstructor`:
 
 ```dart
 import 'dart:html';
@@ -73,11 +133,45 @@
 `USBDevice` ([#42200][]) due to historical reasons. These native interfaces are
 marked with `@Native`, are private, and have no attributes associated with them.
 Therefore, unlike other `@Native` objects, we can’t access any of the APIs or
-attributes associated with this interface. We can use the `js_util` library
-again to circumvent this issue. For example, we can manipulate a
-`_SubtleCrypto` object:
+attributes associated with this interface. We can again either use the
+`@staticInterop` annotation or use the `js_util` library to circumvent this
+issue. For example, we can abstract a `_SubtleCrypto` object:
 
 ```dart
+@JS()
+library workarounds;
+
+import 'dart:html';
+import 'dart:js_util' as js_util;
+import 'dart:typed_data';
+
+import 'package:js/js.dart';
+
+@JS()
+external Crypto get crypto;
+
+@JS()
+@staticInterop
+class JSSubtleCrypto {}
+
+extension JSSubtleCryptoExtension on JSSubtleCrypto {
+  external dynamic digest(String algorithm, Uint8List data);
+  Future<ByteBuffer> digestFuture(String algorithm, Uint8List data) =>
+      js_util.promiseToFuture(digest(algorithm, data));
+}
+
+void main() async {
+  var subtle = crypto.subtle! as JSSubtleCrypto;
+  var digest = await subtle.digestFuture('SHA-256', Uint8List(16));
+}
+```
+
+or with `js_util`:
+
+```dart
+@JS()
+library workarounds;
+
 import 'dart:html';
 import 'dart:js_util' as js_util;
 import 'dart:typed_data';
@@ -96,10 +190,17 @@
 }
 ```
 
-What you shouldn’t do is attempt to cast these native objects using your own JS
-interop types, e.g.
+## Workarounds to Avoid
+
+### Using non-`@staticInterop` `package:js` types
+
+Avoid casting these native objects to non-`@staticInterop` `package:js` types
+e.g.
 
 ```dart
+@JS()
+library workarounds;
+
 import 'dart:html';
 
 import 'package:js/js.dart';
@@ -115,14 +216,40 @@
 }
 ```
 
-With the above, you’ll see a type error:
+With the above, you’ll see a static error:
 
-`Uncaught TypeError: Instance of 'SubtleCrypto': type 'Interceptor' is not a subtype of type 'SubtleCrypto'`
+`Error: Non-static JS interop class 'SubtleCrypto' conflicts with natively supported class '_SubtleCrypto' in 'dart:html'.`
 
 This is because the types in the `@Native` annotation are reserved and the above
 leads to namespace conflicts between the `@Native` type and the user JS interop
-type in the compiler. These `@Native` types inherit the `Interceptor` class,
-which is why you see the message above.
+type in the compiler. `@staticInterop` classes, however, don't have this issue.
+
+### Using extensions on `@Native` types
+
+One alternative that seems viable is to use a static extension on the `@Native`
+type in `dart:html` directly, e.g.
+
+```dart
+extension FileReaderExtension on FileReader {
+  external void readAsBinaryString(Blob blob);
+}
+```
+
+This may work fine, as long as `FileReader` does not add `readAsBinaryString`.
+In the case where this API is added to the class, Dart will [prioritize][] that
+instance method over the extension method you wrote. This may lead to issues,
+like a type error when the signatures between the two methods are incompatible,
+or confusing runtime behavior.
+
+Furthermore, you may come across API conflicts with other users who have also
+defined extension methods on these `@Native` types.
+
+To avoid the above, it's recommended you stick with `@staticInterop`.
+
+In the future, when views/extension types are introduced to the language, this
+guidance will likely change so that you can directly use views on `@Native`
+types.
 
 [#42834]: https://github.com/dart-lang/sdk/issues/42834
 [#42200]: https://github.com/dart-lang/sdk/issues/42200
+[prioritize]: https://github.com/dart-lang/language/blob/master/accepted/2.7/static-extension-methods/feature-specification.md#member-conflict-resolution
diff --git a/sdk/lib/indexed_db/dart2js/indexed_db_dart2js.dart b/sdk/lib/indexed_db/dart2js/indexed_db_dart2js.dart
index ad56eea..e26356c 100644
--- a/sdk/lib/indexed_db/dart2js/indexed_db_dart2js.dart
+++ b/sdk/lib/indexed_db/dart2js/indexed_db_dart2js.dart
@@ -75,7 +75,7 @@
 import 'dart:typed_data';
 import 'dart:_js_helper' show Creates, Returns, JSName, Native;
 import 'dart:_foreign_helper' show JS;
-import 'dart:_interceptors' show Interceptor, JSExtendableArray;
+import 'dart:_interceptors' show JavaScriptObject, JSExtendableArray;
 import 'dart:_js_helper' show convertDartClosureToJS;
 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
@@ -205,7 +205,7 @@
 
 @Unstable()
 @Native("IDBCursor")
-class Cursor extends Interceptor {
+class Cursor extends JavaScriptObject {
   Future delete() {
     try {
       return _completeRequest(_delete());
@@ -448,7 +448,7 @@
 @SupportedBrowser(SupportedBrowser.IE, '10')
 @Unstable()
 @Native("IDBFactory")
-class IdbFactory extends Interceptor {
+class IdbFactory extends JavaScriptObject {
   /**
    * Checks to see if Indexed DB is supported on the current platform.
    */
@@ -554,7 +554,7 @@
 
 @Unstable()
 @Native("IDBIndex")
-class Index extends Interceptor {
+class Index extends JavaScriptObject {
   Future<int> count([key_OR_range]) {
     try {
       var request = _count(key_OR_range);
@@ -696,7 +696,7 @@
 
 @Unstable()
 @Native("IDBKeyRange")
-class KeyRange extends Interceptor {
+class KeyRange extends JavaScriptObject {
   factory KeyRange.only(/*Key*/ value) =>
       _KeyRangeFactoryProvider.createKeyRange_only(value);
 
@@ -747,7 +747,7 @@
 
 @Unstable()
 @Native("IDBObjectStore")
-class ObjectStore extends Interceptor {
+class ObjectStore extends JavaScriptObject {
   Future add(value, [key]) {
     try {
       var request;
@@ -1012,7 +1012,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("IDBObservation")
-class Observation extends Interceptor {
+class Observation extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Observation._() {
     throw new UnsupportedError("Not supported");
@@ -1029,7 +1029,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("IDBObserver")
-class Observer extends Interceptor {
+class Observer extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Observer._() {
     throw new UnsupportedError("Not supported");
@@ -1058,7 +1058,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("IDBObserverChanges")
-class ObserverChanges extends Interceptor {
+class ObserverChanges extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ObserverChanges._() {
     throw new UnsupportedError("Not supported");
diff --git a/sdk/lib/io/overrides.dart b/sdk/lib/io/overrides.dart
index c97e84d..a124c76 100644
--- a/sdk/lib/io/overrides.dart
+++ b/sdk/lib/io/overrides.dart
@@ -81,10 +81,10 @@
 
       // Socket
       Future<Socket> Function(dynamic, int,
-              {dynamic sourceAddress, Duration? timeout})?
+              {dynamic sourceAddress, int sourcePort, Duration? timeout})?
           socketConnect,
       Future<ConnectionTask<Socket>> Function(dynamic, int,
-              {dynamic sourceAddress})?
+              {dynamic sourceAddress, int sourcePort})?
           socketStartConnect,
 
       // ServerSocket
@@ -269,9 +269,9 @@
   /// When this override is installed, this functions overrides the behavior of
   /// `Socket.connect(...)`.
   Future<Socket> socketConnect(host, int port,
-      {sourceAddress, Duration? timeout}) {
+      {sourceAddress, int sourcePort = 0, Duration? timeout}) {
     return Socket._connect(host, port,
-        sourceAddress: sourceAddress, timeout: timeout);
+        sourceAddress: sourceAddress, sourcePort: sourcePort, timeout: timeout);
   }
 
   /// Asynchronously returns a [ConnectionTask] that connects to the given host
@@ -280,8 +280,9 @@
   /// When this override is installed, this functions overrides the behavior of
   /// `Socket.startConnect(...)`.
   Future<ConnectionTask<Socket>> socketStartConnect(host, int port,
-      {sourceAddress}) {
-    return Socket._startConnect(host, port, sourceAddress: sourceAddress);
+      {sourceAddress, int sourcePort = 0}) {
+    return Socket._startConnect(host, port,
+        sourceAddress: sourceAddress, sourcePort: sourcePort);
   }
 
   // ServerSocket
@@ -355,9 +356,11 @@
 
   // Socket
   Future<Socket> Function(dynamic, int,
-      {dynamic sourceAddress, Duration? timeout})? _socketConnect;
+      {dynamic sourceAddress,
+      int sourcePort,
+      Duration? timeout})? _socketConnect;
   Future<ConnectionTask<Socket>> Function(dynamic, int,
-      {dynamic sourceAddress})? _socketStartConnect;
+      {dynamic sourceAddress, int sourcePort})? _socketStartConnect;
 
   // ServerSocket
   Future<ServerSocket> Function(dynamic, int,
@@ -518,30 +521,34 @@
   // Socket
   @override
   Future<Socket> socketConnect(host, int port,
-      {sourceAddress, Duration? timeout}) {
+      {sourceAddress, int sourcePort = 0, Duration? timeout}) {
     if (_socketConnect != null) {
       return _socketConnect!(host, port,
           sourceAddress: sourceAddress, timeout: timeout);
     }
     if (_previous != null) {
       return _previous!.socketConnect(host, port,
-          sourceAddress: sourceAddress, timeout: timeout);
+          sourceAddress: sourceAddress,
+          sourcePort: sourcePort,
+          timeout: timeout);
     }
     return super.socketConnect(host, port,
-        sourceAddress: sourceAddress, timeout: timeout);
+        sourceAddress: sourceAddress, sourcePort: sourcePort, timeout: timeout);
   }
 
   @override
   Future<ConnectionTask<Socket>> socketStartConnect(host, int port,
-      {sourceAddress}) {
+      {sourceAddress, int sourcePort = 0}) {
     if (_socketStartConnect != null) {
-      return _socketStartConnect!(host, port, sourceAddress: sourceAddress);
+      return _socketStartConnect!(host, port,
+          sourceAddress: sourceAddress, sourcePort: sourcePort);
     }
     if (_previous != null) {
-      return _previous!
-          .socketStartConnect(host, port, sourceAddress: sourceAddress);
+      return _previous!.socketStartConnect(host, port,
+          sourceAddress: sourceAddress, sourcePort: sourcePort);
     }
-    return super.socketStartConnect(host, port, sourceAddress: sourceAddress);
+    return super.socketStartConnect(host, port,
+        sourceAddress: sourceAddress, sourcePort: sourcePort);
   }
 
   // ServerSocket
diff --git a/sdk/lib/io/platform.dart b/sdk/lib/io/platform.dart
index 296456f..93bcbd4 100644
--- a/sdk/lib/io/platform.dart
+++ b/sdk/lib/io/platform.dart
@@ -205,11 +205,6 @@
   /// Provides a new list every time the value is read.
   static List<String> get executableArguments => _Platform.executableArguments;
 
-  /// This returns `null`, as `packages/` directories are no longer supported.
-  ///
-  @Deprecated('packages/ directory resolution is not supported in Dart 2')
-  static String? get packageRoot => null; // TODO(mfairhurst): remove this
-
   /// The `--packages` flag passed to the executable used to run the script
   /// in this isolate.
   ///
diff --git a/sdk/lib/io/socket.dart b/sdk/lib/io/socket.dart
index 26cb3ef..3c102c5 100644
--- a/sdk/lib/io/socket.dart
+++ b/sdk/lib/io/socket.dart
@@ -589,19 +589,22 @@
   /// be a [String] or an [InternetAddress]. If a [String] is passed it must
   /// hold a numeric IP address.
   ///
+  /// The [sourcePort] defines the local port to bind to. If [sourcePort] is
+  /// not specified or zero, a port will be chosen.
+  ///
   /// The argument [timeout] is used to specify the maximum allowed time to wait
   /// for a connection to be established. If [timeout] is longer than the system
   /// level timeout duration, a timeout may occur sooner than specified in
   /// [timeout]. On timeout, a [SocketException] is thrown and all ongoing
   /// connection attempts to [host] are cancelled.
   external static Future<RawSocket> connect(host, int port,
-      {sourceAddress, Duration? timeout});
+      {sourceAddress, int sourcePort = 0, Duration? timeout});
 
   /// Like [connect], but returns a [Future] that completes with a
   /// [ConnectionTask] that can be cancelled if the [RawSocket] is no
   /// longer needed.
   external static Future<ConnectionTask<RawSocket>> startConnect(host, int port,
-      {sourceAddress});
+      {sourceAddress, int sourcePort = 0});
 
   /// The number of received and non-read bytes in the socket that can be read.
   int available();
@@ -758,40 +761,46 @@
   /// be a [String] or an [InternetAddress]. If a [String] is passed it must
   /// hold a numeric IP address.
   ///
+  /// The [sourcePort] defines the local port to bind to. If [sourcePort] is
+  /// not specified or zero, a port will be chosen.
+  ///
   /// The argument [timeout] is used to specify the maximum allowed time to wait
   /// for a connection to be established. If [timeout] is longer than the system
   /// level timeout duration, a timeout may occur sooner than specified in
   /// [timeout]. On timeout, a [SocketException] is thrown and all ongoing
   /// connection attempts to [host] are cancelled.
   static Future<Socket> connect(host, int port,
-      {sourceAddress, Duration? timeout}) {
+      {sourceAddress, int sourcePort = 0, Duration? timeout}) {
     final IOOverrides? overrides = IOOverrides.current;
     if (overrides == null) {
       return Socket._connect(host, port,
-          sourceAddress: sourceAddress, timeout: timeout);
+          sourceAddress: sourceAddress,
+          sourcePort: sourcePort,
+          timeout: timeout);
     }
     return overrides.socketConnect(host, port,
-        sourceAddress: sourceAddress, timeout: timeout);
+        sourceAddress: sourceAddress, sourcePort: sourcePort, timeout: timeout);
   }
 
   /// Like [connect], but returns a [Future] that completes with a
   /// [ConnectionTask] that can be cancelled if the [Socket] is no
   /// longer needed.
   static Future<ConnectionTask<Socket>> startConnect(host, int port,
-      {sourceAddress}) {
+      {sourceAddress, int sourcePort = 0}) {
     final IOOverrides? overrides = IOOverrides.current;
     if (overrides == null) {
-      return Socket._startConnect(host, port, sourceAddress: sourceAddress);
+      return Socket._startConnect(host, port,
+          sourceAddress: sourceAddress, sourcePort: sourcePort);
     }
     return overrides.socketStartConnect(host, port,
-        sourceAddress: sourceAddress);
+        sourceAddress: sourceAddress, sourcePort: sourcePort);
   }
 
   external static Future<Socket> _connect(host, int port,
-      {sourceAddress, Duration? timeout});
+      {sourceAddress, int sourcePort = 0, Duration? timeout});
 
   external static Future<ConnectionTask<Socket>> _startConnect(host, int port,
-      {sourceAddress});
+      {sourceAddress, int sourcePort = 0});
 
   /// Destroys the socket in both directions.
   ///
diff --git a/sdk/lib/isolate/isolate.dart b/sdk/lib/isolate/isolate.dart
index 438e967..48c046f 100644
--- a/sdk/lib/isolate/isolate.dart
+++ b/sdk/lib/isolate/isolate.dart
@@ -18,8 +18,8 @@
 /// {@category VM}
 library dart.isolate;
 
-import "dart:async";
 import "dart:_internal" show Since;
+import "dart:async";
 import "dart:typed_data" show ByteBuffer, TypedData, Uint8List;
 
 part "capability.dart";
@@ -158,13 +158,6 @@
   /// is a sure way to hang your program.
   external static Isolate get current;
 
-  /// The package root of the current isolate, if any.
-  ///
-  /// This getter returns `null`, as the `packages/` directory is not supported
-  /// in Dart 2.
-  @Deprecated('packages/ directory resolution is not supported in Dart 2.')
-  external static Future<Uri?> get packageRoot;
-
   /// The location of the package configuration of the current isolate, if any.
   ///
   /// If the isolate has not been setup for package resolution,
diff --git a/sdk/lib/js/_js_annotations.dart b/sdk/lib/js/_js_annotations.dart
index b110632..2e24deb 100644
--- a/sdk/lib/js/_js_annotations.dart
+++ b/sdk/lib/js/_js_annotations.dart
@@ -18,10 +18,10 @@
   const _Anonymous();
 }
 
-// class _StaticInterop {
-//   const _StaticInterop();
-// }
+class _StaticInterop {
+  const _StaticInterop();
+}
 
 const _Anonymous anonymous = _Anonymous();
 
-// const _StaticInterop staticInterop = _StaticInterop();
+const _StaticInterop staticInterop = _StaticInterop();
diff --git a/sdk/lib/math/math.dart b/sdk/lib/math/math.dart
index ad1da4d..d9e3f75 100644
--- a/sdk/lib/math/math.dart
+++ b/sdk/lib/math/math.dart
@@ -8,6 +8,71 @@
 /// ```dart
 /// import 'dart:math';
 /// ```
+///
+/// ## Random
+/// [Random] is a generator of [bool], [int] or [double] values.
+/// ```dart
+/// var intValue = Random().nextInt(10); // Value is >= 0.0 and < 1.0.
+/// var doubleValue = Random().nextDouble(); // Value is >= 0.0 and < 1.0.
+/// var boolValue = Random().nextBool(); // true or false, with equal chance.
+/// ```
+///
+/// ## Point
+/// [Point] is a utility class for representing two-dimensional positions.
+/// ```dart
+/// var leftTop = const Point(0, 0);
+/// var rightBottom = const Point(200, 400);
+/// ```
+///
+/// ## Rectangle
+/// [Rectangle] is a class for representing two-dimensional axis-aligned
+/// rectangles whose properties are immutable.
+///
+/// Create a rectangle spanned by the points.
+/// ```dart
+/// var leftTop = const Point(20, 50);
+/// var rightBottom = const Point(300, 600);
+/// var rectangle = Rectangle.fromPoints(leftTop, rightBottom);
+/// print(rectangle.left); // 20
+/// print(rectangle.top); // 50
+/// print(rectangle.right); // 300
+/// print(rectangle.bottom); // 600
+/// ```
+///
+/// Create a rectangle spanned by `(left, top)` and
+/// `(left+width, top+height)`.
+/// ```dart
+/// var rectangle = const Rectangle(20, 50, 300, 600);
+/// print(rectangle.left); // 20
+/// print(rectangle.top); // 50
+/// print(rectangle.right); // 320
+/// print(rectangle.bottom); // 650
+/// ```
+///
+/// ## MutableRectangle
+/// [MutableRectangle] is a class for representing two-dimensional axis-aligned
+/// rectangles with mutable properties.
+///
+/// Create a mutable rectangle spanned by `(left, top)` and
+/// `(left+width, top+height)`.
+/// ```dart
+/// var rectangle = MutableRectangle(20, 50, 300, 600);
+/// print(rectangle); // Rectangle (20, 50) 300 x 600
+/// print(rectangle.left); // 20
+/// print(rectangle.top); // 50
+/// print(rectangle.right); // 320
+/// print(rectangle.bottom); // 650
+///
+/// // Change rectangle width and height.
+/// rectangle.width = 200;
+/// rectangle.height = 100;
+/// print(rectangle); // Rectangle (20, 50) 200 x 100
+/// print(rectangle.left); // 20
+/// print(rectangle.top); // 50
+/// print(rectangle.right); // 220
+/// print(rectangle.bottom); // 150
+/// ```
+///
 /// {@category Core}
 library dart.math;
 
@@ -101,7 +166,7 @@
 ///
 /// - if `y` is zero (0.0 or -0.0), the result is always 1.0.
 /// - if `x` is 1.0, the result is always 1.0.
-/// - otherwise, if either `x` or `y` is NaN then the result is NaN.
+/// - otherwise, if either `x` or `y` is NaN, then the result is NaN.
 /// - if `x` is negative (but not -0.0) and `y` is a finite non-integer, the
 ///   result is NaN.
 /// - if `x` is Infinity and `y` is negative, the result is 0.0.
@@ -165,6 +230,16 @@
 /// value.
 ///
 /// Returns -0.0 if [x] is -0.0, and NaN if [x] is otherwise negative or NaN.
+/// ```dart
+/// var result = sqrt(9.3);
+/// print(result); // 3.0495901363953815
+/// result = sqrt(2);
+/// print(result); // 1.4142135623730951
+/// result = sqrt(0);
+/// print(result); // 0.0
+/// result = sqrt(-2.2);
+/// print(result); // NaN
+/// ```
 external double sqrt(num x);
 
 /// Converts [x] to a [double] and returns the natural exponent, [e],
diff --git a/sdk/lib/math/point.dart b/sdk/lib/math/point.dart
index df26e9a..1291e23 100644
--- a/sdk/lib/math/point.dart
+++ b/sdk/lib/math/point.dart
@@ -5,6 +5,12 @@
 part of dart.math;
 
 /// A utility class for representing two-dimensional positions.
+///
+/// Example:
+/// ```dart
+/// var leftTop = const Point(0, 0);
+/// var rightBottom = const Point(200, 400);
+/// ```
 class Point<T extends num> {
   final T x;
   final T y;
@@ -21,6 +27,12 @@
   /// Returns `true` if [other] is a [Point] with [x] and [y]
   /// coordinates equal to the corresponding coordinates of this point,
   /// and `false` otherwise.
+  ///
+  /// Example:
+  /// ```dart
+  /// var result = const Point(0, 0) == const Point(0, 0); // true
+  /// result = const Point(1.0, 0) == const Point(-1.0, 0); // false
+  /// ```
   bool operator ==(Object other) =>
       other is Point && x == other.x && y == other.y;
 
@@ -29,6 +41,12 @@
   /// Add [other] to `this`, as if both points were vectors.
   ///
   /// Returns the resulting "vector" as a Point.
+  ///
+  /// Example:
+  /// ```dart
+  /// var point = const Point(10, 100) + const Point(10, 10); // Point(20, 110)
+  /// point = const Point(-10, -20) + const Point(10, 100); // Point(0, 80)
+  /// ```
   Point<T> operator +(Point<T> other) {
     return Point<T>((x + other.x) as T, (y + other.y) as T);
   }
@@ -36,26 +54,57 @@
   /// Subtract [other] from `this`, as if both points were vectors.
   ///
   /// Returns the resulting "vector" as a Point.
+  ///
+  /// Example:
+  /// ```dart
+  /// var point = const Point(10, 100) - const Point(10, 10); // Point(0, 90)
+  /// point = const Point(-10, -20) - const Point(10, 100); // Point(-110, -120)
+  /// ```
   Point<T> operator -(Point<T> other) {
     return Point<T>((x - other.x) as T, (y - other.y) as T);
   }
 
   /// Scale this point by [factor] as if it were a vector.
   ///
-  /// *Important* *Note*: This function accepts a `num` as its argument only so
+  /// **Important Note**: This function accepts a `num` as its argument only so
   /// that you can scale `Point<double>` objects by an `int` factor. Because the
   /// `*` operator always returns the same type of `Point` as it is called on,
   /// passing in a double [factor] on a `Point<int>` _causes_ _a_
   /// _runtime_ _error_.
+  ///
+  /// Example:
+  /// ```dart
+  /// // Integer values.
+  /// var point = const Point(10, 100) * 10; // Point(100, 1000)
+  /// point = const Point(-10, -100) * 5; // Point(-50, -500)
+  /// // Double values.
+  /// var doublePoint = Point(10.0, 100.0) * 1.5; // Point(15.0, 150.0)
+  /// // Runtime error due the invalid type cast.
+  /// var newPoint = const Point(10, 100) * 1.5; // Throws.
+  /// ```
   Point<T> operator *(num /*T|int*/ factor) {
     return Point<T>((x * factor) as T, (y * factor) as T);
   }
 
   /// Get the straight line (Euclidean) distance between the origin (0, 0) and
   /// this point.
+  ///
+  /// Example:
+  /// ```dart
+  /// var magnitude = const Point(0, 0).magnitude; // 0.0
+  /// magnitude = const Point(10, 0).magnitude;  // 10.0
+  /// magnitude = const Point(0, -10).magnitude; // 10.0
+  /// magnitude = const Point(10, 10).magnitude;  // 14.142135623730951
+  /// ```
   double get magnitude => sqrt(x * x + y * y);
 
   /// Returns the distance between `this` and [other].
+  /// ```dart
+  /// var distanceTo = const Point(0, 0).distanceTo(const Point(0, 0)); // 0.0
+  /// distanceTo = const Point(0, 0).distanceTo(const Point(10, 0)); // 10.0
+  /// distanceTo = const Point(0, 0).distanceTo(const Point(0, -10)); // 10.0
+  /// distanceTo = const Point(-10, 0).distanceTo(const Point(100, 0)); // 110.0
+  /// ```
   double distanceTo(Point<T> other) {
     var dx = x - other.x;
     var dy = y - other.y;
@@ -66,6 +115,18 @@
   ///
   /// Squared distances can be used for comparisons when the actual value is not
   /// required.
+  ///
+  /// Example:
+  /// ```dart
+  /// var squaredDistance =
+  ///     const Point(0, 0).squaredDistanceTo(const Point(0, 0)); // 0.0
+  /// squaredDistance =
+  ///     const Point(0, 0).squaredDistanceTo(const Point(10, 0)); // 100
+  /// squaredDistance =
+  ///     const Point(0, 0).squaredDistanceTo(const Point(0, -10)); // 100
+  /// squaredDistance =
+  ///     const Point(-10, 0).squaredDistanceTo(const Point(100, 0)); // 12100
+  /// ```
   T squaredDistanceTo(Point<T> other) {
     var dx = x - other.x;
     var dy = y - other.y;
diff --git a/sdk/lib/math/rectangle.dart b/sdk/lib/math/rectangle.dart
index 1fe8ea9..fd7d783 100644
--- a/sdk/lib/math/rectangle.dart
+++ b/sdk/lib/math/rectangle.dart
@@ -11,7 +11,7 @@
 /// computer graphics.
 ///
 /// See also:
-///    [W3C Coordinate Systems Specification](http://www.w3.org/TR/SVG/coords.html#InitialCoordinateSystem).
+///    [W3C Coordinate Systems Specification](https://www.w3.org/TR/SVG/coords.html#InitialCoordinateSystem).
 ///
 /// The rectangle is the set of points with representable coordinates greater
 /// than or equal to left/top, and with distance to left/top no greater than
@@ -135,6 +135,15 @@
   ///
   /// If `width` and `height` are zero, the "rectangle" comprises only the
   /// single point `(left, top)`.
+  ///
+  /// Example:
+  /// ```dart
+  /// var rectangle = const Rectangle(20, 50, 300, 600);
+  /// print(rectangle.left); // 20
+  /// print(rectangle.top); // 50
+  /// print(rectangle.right); // 320
+  /// print(rectangle.bottom); // 650
+  /// ```
   const Rectangle(this.left, this.top, T width, T height)
       : width = (width < 0)
             ? (width == double.negativeInfinity ? 0.0 : (-width * 0)) as dynamic
@@ -154,6 +163,19 @@
   /// (which can happen if one or both is a double),
   /// the actual right edge might be slightly off from `max(a.x, b.x)`.
   /// Similar for the y-coordinates and the bottom edge.
+  ///
+  /// Example:
+  /// ```dart
+  /// var leftTop = const Point(20, 50);
+  /// var rightBottom = const Point(300, 600);
+  ///
+  /// var rectangle = Rectangle.fromPoints(leftTop, rightBottom);
+  /// print(rectangle); // Rectangle (20, 50) 280 x 550
+  /// print(rectangle.left); // 20
+  /// print(rectangle.top); // 50
+  /// print(rectangle.right); // 300
+  /// print(rectangle.bottom); // 600
+  /// ```
   factory Rectangle.fromPoints(Point<T> a, Point<T> b) {
     T left = min(a.x, b.x);
     T width = (max(a.x, b.x) - left) as T;
@@ -191,6 +213,26 @@
   ///
   /// If `width` and `height` are zero, the "rectangle" comprises only the
   /// single point `(left, top)`.
+  ///
+  /// Example:
+  /// ```dart
+  /// var rectangle = MutableRectangle(20, 50, 300, 600);
+  /// print(rectangle); // Rectangle (20, 50) 300 x 600
+  /// print(rectangle.left); // 20
+  /// print(rectangle.top); // 50
+  /// print(rectangle.right); // 320
+  /// print(rectangle.bottom); // 650
+  ///
+  /// // Change rectangle width and height.
+  /// rectangle.width = 200;
+  /// rectangle.height = 100;
+  ///
+  /// print(rectangle); // Rectangle (20, 50) 200 x 100
+  /// print(rectangle.left); // 20
+  /// print(rectangle.top); // 50
+  /// print(rectangle.right); // 220
+  /// print(rectangle.bottom); // 150
+  /// ```
   MutableRectangle(this.left, this.top, T width, T height)
       : this._width =
             (width < 0) ? _clampToZero<T>(width) : (width + 0 as dynamic),
@@ -207,6 +249,18 @@
   /// (which can happen if one or both is a double),
   /// the actual right edge might be slightly off from `max(a.x, b.x)`.
   /// Similar for the y-coordinates and the bottom edge.
+  ///
+  /// Example:
+  /// ```dart
+  /// var leftTop = const Point(20, 50);
+  /// var rightBottom = const Point(300, 600);
+  /// var rectangle = MutableRectangle.fromPoints(leftTop, rightBottom);
+  /// print(rectangle); // Rectangle (20, 50) 280 x 550
+  /// print(rectangle.left); // 20
+  /// print(rectangle.top); // 50
+  /// print(rectangle.right); // 300
+  /// print(rectangle.bottom); // 600
+  /// ```
   factory MutableRectangle.fromPoints(Point<T> a, Point<T> b) {
     T left = min(a.x, b.x);
     T width = (max(a.x, b.x) - left) as T;
diff --git a/sdk/lib/svg/dart2js/svg_dart2js.dart b/sdk/lib/svg/dart2js/svg_dart2js.dart
index aa97d19..9b2e992 100644
--- a/sdk/lib/svg/dart2js/svg_dart2js.dart
+++ b/sdk/lib/svg/dart2js/svg_dart2js.dart
@@ -17,7 +17,7 @@
 import 'dart:html_common';
 import 'dart:_js_helper' show Creates, Returns, JSName, Native;
 import 'dart:_foreign_helper' show JS;
-import 'dart:_interceptors' show Interceptor;
+import 'dart:_interceptors' show JavaScriptObject;
 // DO NOT EDIT - unless you are editing documentation as per:
 // https://code.google.com/p/dart/wiki/ContributingHTMLDocumentation
 // Auto-generated dart:svg library.
@@ -66,7 +66,7 @@
 
 @Unstable()
 @Native("SVGAngle")
-class Angle extends Interceptor {
+class Angle extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Angle._() {
     throw new UnsupportedError("Not supported");
@@ -196,7 +196,7 @@
 
 @Unstable()
 @Native("SVGAnimatedAngle")
-class AnimatedAngle extends Interceptor {
+class AnimatedAngle extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AnimatedAngle._() {
     throw new UnsupportedError("Not supported");
@@ -212,7 +212,7 @@
 
 @Unstable()
 @Native("SVGAnimatedBoolean")
-class AnimatedBoolean extends Interceptor {
+class AnimatedBoolean extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AnimatedBoolean._() {
     throw new UnsupportedError("Not supported");
@@ -230,7 +230,7 @@
 
 @Unstable()
 @Native("SVGAnimatedEnumeration")
-class AnimatedEnumeration extends Interceptor {
+class AnimatedEnumeration extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AnimatedEnumeration._() {
     throw new UnsupportedError("Not supported");
@@ -248,7 +248,7 @@
 
 @Unstable()
 @Native("SVGAnimatedInteger")
-class AnimatedInteger extends Interceptor {
+class AnimatedInteger extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AnimatedInteger._() {
     throw new UnsupportedError("Not supported");
@@ -266,7 +266,7 @@
 
 @Unstable()
 @Native("SVGAnimatedLength")
-class AnimatedLength extends Interceptor {
+class AnimatedLength extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AnimatedLength._() {
     throw new UnsupportedError("Not supported");
@@ -282,7 +282,7 @@
 
 @Unstable()
 @Native("SVGAnimatedLengthList")
-class AnimatedLengthList extends Interceptor {
+class AnimatedLengthList extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AnimatedLengthList._() {
     throw new UnsupportedError("Not supported");
@@ -298,7 +298,7 @@
 
 @Unstable()
 @Native("SVGAnimatedNumber")
-class AnimatedNumber extends Interceptor {
+class AnimatedNumber extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AnimatedNumber._() {
     throw new UnsupportedError("Not supported");
@@ -316,7 +316,7 @@
 
 @Unstable()
 @Native("SVGAnimatedNumberList")
-class AnimatedNumberList extends Interceptor {
+class AnimatedNumberList extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AnimatedNumberList._() {
     throw new UnsupportedError("Not supported");
@@ -332,7 +332,7 @@
 
 @Unstable()
 @Native("SVGAnimatedPreserveAspectRatio")
-class AnimatedPreserveAspectRatio extends Interceptor {
+class AnimatedPreserveAspectRatio extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AnimatedPreserveAspectRatio._() {
     throw new UnsupportedError("Not supported");
@@ -348,7 +348,7 @@
 
 @Unstable()
 @Native("SVGAnimatedRect")
-class AnimatedRect extends Interceptor {
+class AnimatedRect extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AnimatedRect._() {
     throw new UnsupportedError("Not supported");
@@ -364,7 +364,7 @@
 
 @Unstable()
 @Native("SVGAnimatedString")
-class AnimatedString extends Interceptor {
+class AnimatedString extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AnimatedString._() {
     throw new UnsupportedError("Not supported");
@@ -382,7 +382,7 @@
 
 @Unstable()
 @Native("SVGAnimatedTransformList")
-class AnimatedTransformList extends Interceptor {
+class AnimatedTransformList extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AnimatedTransformList._() {
     throw new UnsupportedError("Not supported");
@@ -1785,7 +1785,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Unstable()
-abstract class FilterPrimitiveStandardAttributes extends Interceptor {
+abstract class FilterPrimitiveStandardAttributes extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory FilterPrimitiveStandardAttributes._() {
     throw new UnsupportedError("Not supported");
@@ -1806,7 +1806,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Unstable()
-abstract class FitToViewBox extends Interceptor {
+abstract class FitToViewBox extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory FitToViewBox._() {
     throw new UnsupportedError("Not supported");
@@ -1986,7 +1986,7 @@
 
 @Unstable()
 @Native("SVGLength")
-class Length extends Interceptor {
+class Length extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Length._() {
     throw new UnsupportedError("Not supported");
@@ -2038,7 +2038,7 @@
 
 @Unstable()
 @Native("SVGLengthList")
-class LengthList extends Interceptor
+class LengthList extends JavaScriptObject
     with ListMixin<Length>, ImmutableListMixin<Length>
     implements List<Length> {
   // To suppress missing implicit constructor warnings.
@@ -2271,7 +2271,7 @@
 
 @Unstable()
 @Native("SVGMatrix")
-class Matrix extends Interceptor {
+class Matrix extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Matrix._() {
     throw new UnsupportedError("Not supported");
@@ -2347,7 +2347,7 @@
 
 @Unstable()
 @Native("SVGNumber")
-class Number extends Interceptor {
+class Number extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Number._() {
     throw new UnsupportedError("Not supported");
@@ -2363,7 +2363,7 @@
 
 @Unstable()
 @Native("SVGNumberList")
-class NumberList extends Interceptor
+class NumberList extends JavaScriptObject
     with ListMixin<Number>, ImmutableListMixin<Number>
     implements List<Number> {
   // To suppress missing implicit constructor warnings.
@@ -2514,7 +2514,7 @@
 
 @Unstable()
 @Native("SVGPoint")
-class Point extends Interceptor {
+class Point extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Point._() {
     throw new UnsupportedError("Not supported");
@@ -2536,7 +2536,7 @@
 
 @Unstable()
 @Native("SVGPointList")
-class PointList extends Interceptor {
+class PointList extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PointList._() {
     throw new UnsupportedError("Not supported");
@@ -2620,7 +2620,7 @@
 
 @Unstable()
 @Native("SVGPreserveAspectRatio")
-class PreserveAspectRatio extends Interceptor {
+class PreserveAspectRatio extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PreserveAspectRatio._() {
     throw new UnsupportedError("Not supported");
@@ -2702,7 +2702,7 @@
 
 @Unstable()
 @Native("SVGRect")
-class Rect extends Interceptor {
+class Rect extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Rect._() {
     throw new UnsupportedError("Not supported");
@@ -2846,7 +2846,7 @@
 
 @Unstable()
 @Native("SVGStringList")
-class StringList extends Interceptor
+class StringList extends JavaScriptObject
     with ListMixin<String>, ImmutableListMixin<String>
     implements List<String> {
   // To suppress missing implicit constructor warnings.
@@ -3619,7 +3619,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Unstable()
-abstract class Tests extends Interceptor {
+abstract class Tests extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Tests._() {
     throw new UnsupportedError("Not supported");
@@ -3791,7 +3791,7 @@
 
 @Unstable()
 @Native("SVGTransform")
-class Transform extends Interceptor {
+class Transform extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Transform._() {
     throw new UnsupportedError("Not supported");
@@ -3835,7 +3835,7 @@
 
 @Unstable()
 @Native("SVGTransformList")
-class TransformList extends Interceptor
+class TransformList extends JavaScriptObject
     with ListMixin<Transform>, ImmutableListMixin<Transform>
     implements List<Transform> {
   // To suppress missing implicit constructor warnings.
@@ -3917,7 +3917,7 @@
 
 @Unstable()
 @Native("SVGUnitTypes")
-class UnitTypes extends Interceptor {
+class UnitTypes extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory UnitTypes._() {
     throw new UnsupportedError("Not supported");
@@ -3934,7 +3934,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Unstable()
-abstract class UriReference extends Interceptor {
+abstract class UriReference extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory UriReference._() {
     throw new UnsupportedError("Not supported");
@@ -4013,7 +4013,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Unstable()
-abstract class ZoomAndPan extends Interceptor {
+abstract class ZoomAndPan extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ZoomAndPan._() {
     throw new UnsupportedError("Not supported");
diff --git a/sdk/lib/vmservice/client.dart b/sdk/lib/vmservice/client.dart
index 65a72ba..7ce9c51 100644
--- a/sdk/lib/vmservice/client.dart
+++ b/sdk/lib/vmservice/client.dart
@@ -20,9 +20,12 @@
   set name(String? n) => _name = (n ?? defaultClientName);
   late String _name;
 
-  /// A set streamIds which describes the streams the client is connected to
+  /// The set of streams the client is subscribed to.
   final streams = <String>{};
 
+  /// The set of user tags that the client wants to receive CPU samples for.
+  final profilerUserTagFilters = <String>{};
+
   /// Services registered and their aliases
   /// key: service
   /// value: alias
diff --git a/sdk/lib/vmservice/vmservice.dart b/sdk/lib/vmservice/vmservice.dart
index ed389a7..5af3cfd 100644
--- a/sdk/lib/vmservice/vmservice.dart
+++ b/sdk/lib/vmservice/vmservice.dart
@@ -228,6 +228,8 @@
 
   final devfs = DevFS();
 
+  final _profilerUserTagSubscriptions = <String>{};
+
   Uri? get ddsUri => _ddsUri;
   Uri? _ddsUri;
 
@@ -300,7 +302,7 @@
         _vmCancelStream(streamId);
       }
     }
-
+    _cleanupUnusedUserTagSubscriptions();
     for (final service in client.services.keys) {
       _eventMessageHandler(
           'Service',
@@ -336,10 +338,35 @@
     }
   }
 
+  void _profilerEventMessageHandler(Client client, Response event) {
+    final eventJson = event.decodeJson() as Map<String, dynamic>;
+    final eventData = eventJson['params']!['event']!;
+    if (eventData['kind']! != 'CpuSamples') {
+      client.post(event);
+      return;
+    }
+    final cpuSamplesEvent = eventData['cpuSamples']!;
+    final updatedSamples = cpuSamplesEvent['samples']!
+        .where(
+          (s) => client.profilerUserTagFilters.contains(s['userTag']),
+        )
+        .toList();
+    if (updatedSamples.isEmpty) {
+      return;
+    }
+    cpuSamplesEvent['samples'] = updatedSamples;
+    cpuSamplesEvent['sampleCount'] = updatedSamples.length;
+    client.post(Response.json(eventJson));
+  }
+
   void _eventMessageHandler(String streamId, Response event) {
     for (final client in clients) {
       if (client.sendEvents && client.streams.contains(streamId)) {
-        client.post(event);
+        if (streamId == 'Profiler') {
+          _profilerEventMessageHandler(client, event);
+        } else {
+          client.post(event);
+        }
       }
     }
   }
@@ -665,6 +692,57 @@
     return encodeResult(message, protocols);
   }
 
+  void _cleanupUnusedUserTagSubscriptions() {
+    final unsubscribeableTags = <String>[];
+    for (final subscribedTag in _profilerUserTagSubscriptions) {
+      bool hasSubscriber = false;
+      for (final c in clients) {
+        if (c.profilerUserTagFilters.contains(subscribedTag)) {
+          hasSubscriber = true;
+          break;
+        }
+      }
+      if (!hasSubscriber) {
+        unsubscribeableTags.add(subscribedTag);
+      }
+    }
+    if (unsubscribeableTags.isNotEmpty) {
+      _profilerUserTagSubscriptions.removeAll(unsubscribeableTags);
+      _removeUserTagsFromStreamableSampleList(unsubscribeableTags);
+    }
+  }
+
+  Future<String> _streamCpuSamplesWithUserTag(Message message) async {
+    if (!message.params.containsKey('userTags')) {
+      return encodeRpcError(message, kInvalidParams,
+          details: "Missing required parameter 'userTags'.");
+    }
+
+    // TODO(bkonyi): handle "subscribe all" case.
+    final client = message.client!;
+    final tags = message.params['userTags']!.cast<String>().toSet();
+    final newTags = tags.difference(_profilerUserTagSubscriptions);
+
+    // Clear the previously set user tag subscriptions for the client and
+    // update with the new list of user tags.
+    client.profilerUserTagFilters.clear();
+    _profilerUserTagSubscriptions.addAll(tags);
+    client.profilerUserTagFilters.addAll(tags);
+
+    // If any previously unseen user tag is provided, let the VM know that
+    // samples with that user tag should be streamed on the Profiler stream.
+    if (newTags.isNotEmpty) {
+      _addUserTagsToStreamableSampleList(newTags.toList());
+    }
+
+    // Some user tags may no longer be of any interest to the existing clients.
+    // Check that all user tags have at least one client interested in them,
+    // otherwise notify the VM that we're no longer interested in samples with
+    // those user tags.
+    _cleanupUnusedUserTagSubscriptions();
+    return encodeSuccess(message);
+  }
+
   Future<Response?> routeRequest(VMService _, Message message) async {
     final response = await _routeRequestImpl(message);
     if (response == null) {
@@ -695,6 +773,9 @@
       if (message.method == 'getSupportedProtocols') {
         return await _getSupportedProtocols(message);
       }
+      if (message.method == 'streamCpuSamplesWithUserTag') {
+        return await _streamCpuSamplesWithUserTag(message);
+      }
       if (devfs.shouldHandleMessage(message)) {
         return await devfs.handleMessage(message);
       }
@@ -759,3 +840,9 @@
 /// Get the bytes to the tar archive.
 @pragma("vm:external-name", "VMService_RequestAssets")
 external Uint8List _requestAssets();
+
+@pragma("vm:external-name", "VMService_AddUserTagsToStreamableSampleList")
+external void _addUserTagsToStreamableSampleList(List<String> userTags);
+
+@pragma("vm:external-name", "VMService_RemoveUserTagsFromStreamableSampleList")
+external void _removeUserTagsFromStreamableSampleList(List<String> userTags);
diff --git a/sdk/lib/web_audio/dart2js/web_audio_dart2js.dart b/sdk/lib/web_audio/dart2js/web_audio_dart2js.dart
index 506f9e6..a7db2d5 100644
--- a/sdk/lib/web_audio/dart2js/web_audio_dart2js.dart
+++ b/sdk/lib/web_audio/dart2js/web_audio_dart2js.dart
@@ -13,7 +13,7 @@
 import 'dart:_native_typed_data';
 import 'dart:typed_data';
 import 'dart:_foreign_helper' show JS;
-import 'dart:_interceptors' show Interceptor;
+import 'dart:_interceptors' show JavaScriptObject;
 // DO NOT EDIT - unless you are editing documentation as per:
 // https://code.google.com/p/dart/wiki/ContributingHTMLDocumentation
 // Auto-generated dart:audio library.
@@ -81,7 +81,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("AudioBuffer")
-class AudioBuffer extends Interceptor {
+class AudioBuffer extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AudioBuffer._() {
     throw new UnsupportedError("Not supported");
@@ -268,7 +268,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("AudioListener")
-class AudioListener extends Interceptor {
+class AudioListener extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AudioListener._() {
     throw new UnsupportedError("Not supported");
@@ -343,7 +343,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("AudioParam")
-class AudioParam extends Interceptor {
+class AudioParam extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AudioParam._() {
     throw new UnsupportedError("Not supported");
@@ -379,7 +379,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("AudioParamMap")
-class AudioParamMap extends Interceptor with MapMixin<String, dynamic> {
+class AudioParamMap extends JavaScriptObject with MapMixin<String, dynamic> {
   // To suppress missing implicit constructor warnings.
   factory AudioParamMap._() {
     throw new UnsupportedError("Not supported");
@@ -495,7 +495,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("AudioTrack")
-class AudioTrack extends Interceptor {
+class AudioTrack extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AudioTrack._() {
     throw new UnsupportedError("Not supported");
@@ -589,7 +589,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("AudioWorkletProcessor")
-class AudioWorkletProcessor extends Interceptor {
+class AudioWorkletProcessor extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AudioWorkletProcessor._() {
     throw new UnsupportedError("Not supported");
@@ -1196,7 +1196,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("PeriodicWave")
-class PeriodicWave extends Interceptor {
+class PeriodicWave extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory PeriodicWave._() {
     throw new UnsupportedError("Not supported");
diff --git a/sdk/lib/web_gl/dart2js/web_gl_dart2js.dart b/sdk/lib/web_gl/dart2js/web_gl_dart2js.dart
index 072cfae..473059f 100644
--- a/sdk/lib/web_gl/dart2js/web_gl_dart2js.dart
+++ b/sdk/lib/web_gl/dart2js/web_gl_dart2js.dart
@@ -15,7 +15,7 @@
 import 'dart:_js_helper'
     show Creates, JSName, Native, Returns, convertDartClosureToJS;
 import 'dart:_foreign_helper' show JS;
-import 'dart:_interceptors' show Interceptor, JSExtendableArray;
+import 'dart:_interceptors' show JavaScriptObject, JSExtendableArray;
 // DO NOT EDIT - unless you are editing documentation as per:
 // https://code.google.com/p/dart/wiki/ContributingHTMLDocumentation
 // Auto-generated dart:web_gl library.
@@ -26,7 +26,7 @@
 
 @Unstable()
 @Native("WebGLActiveInfo")
-class ActiveInfo extends Interceptor {
+class ActiveInfo extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ActiveInfo._() {
     throw new UnsupportedError("Not supported");
@@ -43,7 +43,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("ANGLEInstancedArrays,ANGLE_instanced_arrays")
-class AngleInstancedArrays extends Interceptor {
+class AngleInstancedArrays extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory AngleInstancedArrays._() {
     throw new UnsupportedError("Not supported");
@@ -68,7 +68,7 @@
 
 @Unstable()
 @Native("WebGLBuffer")
-class Buffer extends Interceptor {
+class Buffer extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Buffer._() {
     throw new UnsupportedError("Not supported");
@@ -79,7 +79,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLCanvas")
-class Canvas extends Interceptor {
+class Canvas extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Canvas._() {
     throw new UnsupportedError("Not supported");
@@ -97,7 +97,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLColorBufferFloat")
-class ColorBufferFloat extends Interceptor {
+class ColorBufferFloat extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ColorBufferFloat._() {
     throw new UnsupportedError("Not supported");
@@ -108,7 +108,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLCompressedTextureASTC")
-class CompressedTextureAstc extends Interceptor {
+class CompressedTextureAstc extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CompressedTextureAstc._() {
     throw new UnsupportedError("Not supported");
@@ -175,7 +175,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLCompressedTextureATC,WEBGL_compressed_texture_atc")
-class CompressedTextureAtc extends Interceptor {
+class CompressedTextureAtc extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CompressedTextureAtc._() {
     throw new UnsupportedError("Not supported");
@@ -192,7 +192,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLCompressedTextureETC1,WEBGL_compressed_texture_etc1")
-class CompressedTextureETC1 extends Interceptor {
+class CompressedTextureETC1 extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CompressedTextureETC1._() {
     throw new UnsupportedError("Not supported");
@@ -205,7 +205,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLCompressedTextureETC")
-class CompressedTextureEtc extends Interceptor {
+class CompressedTextureEtc extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CompressedTextureEtc._() {
     throw new UnsupportedError("Not supported");
@@ -236,7 +236,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLCompressedTexturePVRTC,WEBGL_compressed_texture_pvrtc")
-class CompressedTexturePvrtc extends Interceptor {
+class CompressedTexturePvrtc extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CompressedTexturePvrtc._() {
     throw new UnsupportedError("Not supported");
@@ -255,7 +255,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLCompressedTextureS3TC,WEBGL_compressed_texture_s3tc")
-class CompressedTextureS3TC extends Interceptor {
+class CompressedTextureS3TC extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CompressedTextureS3TC._() {
     throw new UnsupportedError("Not supported");
@@ -274,7 +274,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLCompressedTextureS3TCsRGB")
-class CompressedTextureS3TCsRgb extends Interceptor {
+class CompressedTextureS3TCsRgb extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory CompressedTextureS3TCsRgb._() {
     throw new UnsupportedError("Not supported");
@@ -319,7 +319,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLDebugRendererInfo,WEBGL_debug_renderer_info")
-class DebugRendererInfo extends Interceptor {
+class DebugRendererInfo extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DebugRendererInfo._() {
     throw new UnsupportedError("Not supported");
@@ -334,7 +334,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLDebugShaders,WEBGL_debug_shaders")
-class DebugShaders extends Interceptor {
+class DebugShaders extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DebugShaders._() {
     throw new UnsupportedError("Not supported");
@@ -347,7 +347,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLDepthTexture,WEBGL_depth_texture")
-class DepthTexture extends Interceptor {
+class DepthTexture extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DepthTexture._() {
     throw new UnsupportedError("Not supported");
@@ -360,7 +360,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLDrawBuffers,WEBGL_draw_buffers")
-class DrawBuffers extends Interceptor {
+class DrawBuffers extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory DrawBuffers._() {
     throw new UnsupportedError("Not supported");
@@ -374,7 +374,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("EXTsRGB,EXT_sRGB")
-class EXTsRgb extends Interceptor {
+class EXTsRgb extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory EXTsRgb._() {
     throw new UnsupportedError("Not supported");
@@ -393,7 +393,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("EXTBlendMinMax,EXT_blend_minmax")
-class ExtBlendMinMax extends Interceptor {
+class ExtBlendMinMax extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ExtBlendMinMax._() {
     throw new UnsupportedError("Not supported");
@@ -408,7 +408,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("EXTColorBufferFloat")
-class ExtColorBufferFloat extends Interceptor {
+class ExtColorBufferFloat extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ExtColorBufferFloat._() {
     throw new UnsupportedError("Not supported");
@@ -419,7 +419,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("EXTColorBufferHalfFloat")
-class ExtColorBufferHalfFloat extends Interceptor {
+class ExtColorBufferHalfFloat extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ExtColorBufferHalfFloat._() {
     throw new UnsupportedError("Not supported");
@@ -430,7 +430,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("EXTDisjointTimerQuery")
-class ExtDisjointTimerQuery extends Interceptor {
+class ExtDisjointTimerQuery extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ExtDisjointTimerQuery._() {
     throw new UnsupportedError("Not supported");
@@ -479,7 +479,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("EXTDisjointTimerQueryWebGL2")
-class ExtDisjointTimerQueryWebGL2 extends Interceptor {
+class ExtDisjointTimerQueryWebGL2 extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ExtDisjointTimerQueryWebGL2._() {
     throw new UnsupportedError("Not supported");
@@ -501,7 +501,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("EXTFragDepth,EXT_frag_depth")
-class ExtFragDepth extends Interceptor {
+class ExtFragDepth extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ExtFragDepth._() {
     throw new UnsupportedError("Not supported");
@@ -512,7 +512,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("EXTShaderTextureLOD,EXT_shader_texture_lod")
-class ExtShaderTextureLod extends Interceptor {
+class ExtShaderTextureLod extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ExtShaderTextureLod._() {
     throw new UnsupportedError("Not supported");
@@ -523,7 +523,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("EXTTextureFilterAnisotropic,EXT_texture_filter_anisotropic")
-class ExtTextureFilterAnisotropic extends Interceptor {
+class ExtTextureFilterAnisotropic extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ExtTextureFilterAnisotropic._() {
     throw new UnsupportedError("Not supported");
@@ -539,7 +539,7 @@
 
 @Unstable()
 @Native("WebGLFramebuffer")
-class Framebuffer extends Interceptor {
+class Framebuffer extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Framebuffer._() {
     throw new UnsupportedError("Not supported");
@@ -550,7 +550,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLGetBufferSubDataAsync")
-class GetBufferSubDataAsync extends Interceptor {
+class GetBufferSubDataAsync extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory GetBufferSubDataAsync._() {
     throw new UnsupportedError("Not supported");
@@ -566,7 +566,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLLoseContext,WebGLExtensionLoseContext,WEBGL_lose_context")
-class LoseContext extends Interceptor {
+class LoseContext extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory LoseContext._() {
     throw new UnsupportedError("Not supported");
@@ -581,7 +581,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("OESElementIndexUint,OES_element_index_uint")
-class OesElementIndexUint extends Interceptor {
+class OesElementIndexUint extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory OesElementIndexUint._() {
     throw new UnsupportedError("Not supported");
@@ -592,7 +592,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("OESStandardDerivatives,OES_standard_derivatives")
-class OesStandardDerivatives extends Interceptor {
+class OesStandardDerivatives extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory OesStandardDerivatives._() {
     throw new UnsupportedError("Not supported");
@@ -605,7 +605,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("OESTextureFloat,OES_texture_float")
-class OesTextureFloat extends Interceptor {
+class OesTextureFloat extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory OesTextureFloat._() {
     throw new UnsupportedError("Not supported");
@@ -616,7 +616,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("OESTextureFloatLinear,OES_texture_float_linear")
-class OesTextureFloatLinear extends Interceptor {
+class OesTextureFloatLinear extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory OesTextureFloatLinear._() {
     throw new UnsupportedError("Not supported");
@@ -627,7 +627,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("OESTextureHalfFloat,OES_texture_half_float")
-class OesTextureHalfFloat extends Interceptor {
+class OesTextureHalfFloat extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory OesTextureHalfFloat._() {
     throw new UnsupportedError("Not supported");
@@ -640,7 +640,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("OESTextureHalfFloatLinear,OES_texture_half_float_linear")
-class OesTextureHalfFloatLinear extends Interceptor {
+class OesTextureHalfFloatLinear extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory OesTextureHalfFloatLinear._() {
     throw new UnsupportedError("Not supported");
@@ -651,7 +651,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("OESVertexArrayObject,OES_vertex_array_object")
-class OesVertexArrayObject extends Interceptor {
+class OesVertexArrayObject extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory OesVertexArrayObject._() {
     throw new UnsupportedError("Not supported");
@@ -677,7 +677,7 @@
 
 @Unstable()
 @Native("WebGLProgram")
-class Program extends Interceptor {
+class Program extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Program._() {
     throw new UnsupportedError("Not supported");
@@ -688,7 +688,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLQuery")
-class Query extends Interceptor {
+class Query extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Query._() {
     throw new UnsupportedError("Not supported");
@@ -700,7 +700,7 @@
 
 @Unstable()
 @Native("WebGLRenderbuffer")
-class Renderbuffer extends Interceptor {
+class Renderbuffer extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Renderbuffer._() {
     throw new UnsupportedError("Not supported");
@@ -714,7 +714,8 @@
 @SupportedBrowser(SupportedBrowser.FIREFOX)
 @Unstable()
 @Native("WebGLRenderingContext")
-class RenderingContext extends Interceptor implements CanvasRenderingContext {
+class RenderingContext extends JavaScriptObject
+    implements CanvasRenderingContext {
   // To suppress missing implicit constructor warnings.
   factory RenderingContext._() {
     throw new UnsupportedError("Not supported");
@@ -1356,7 +1357,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGL2RenderingContext")
-class RenderingContext2 extends Interceptor
+class RenderingContext2 extends JavaScriptObject
     implements _WebGL2RenderingContextBase, _WebGLRenderingContextBase {
   // To suppress missing implicit constructor warnings.
   factory RenderingContext2._() {
@@ -2834,7 +2835,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLSampler")
-class Sampler extends Interceptor {
+class Sampler extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Sampler._() {
     throw new UnsupportedError("Not supported");
@@ -2845,7 +2846,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLShader")
-class Shader extends Interceptor {
+class Shader extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Shader._() {
     throw new UnsupportedError("Not supported");
@@ -2856,7 +2857,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLShaderPrecisionFormat")
-class ShaderPrecisionFormat extends Interceptor {
+class ShaderPrecisionFormat extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory ShaderPrecisionFormat._() {
     throw new UnsupportedError("Not supported");
@@ -2873,7 +2874,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLSync")
-class Sync extends Interceptor {
+class Sync extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Sync._() {
     throw new UnsupportedError("Not supported");
@@ -2884,7 +2885,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLTexture")
-class Texture extends Interceptor {
+class Texture extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory Texture._() {
     throw new UnsupportedError("Not supported");
@@ -2903,7 +2904,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLTimerQueryEXT")
-class TimerQueryExt extends Interceptor {
+class TimerQueryExt extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory TimerQueryExt._() {
     throw new UnsupportedError("Not supported");
@@ -2914,7 +2915,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLTransformFeedback")
-class TransformFeedback extends Interceptor {
+class TransformFeedback extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory TransformFeedback._() {
     throw new UnsupportedError("Not supported");
@@ -2925,7 +2926,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLUniformLocation")
-class UniformLocation extends Interceptor {
+class UniformLocation extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory UniformLocation._() {
     throw new UnsupportedError("Not supported");
@@ -2936,7 +2937,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLVertexArrayObject")
-class VertexArrayObject extends Interceptor {
+class VertexArrayObject extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory VertexArrayObject._() {
     throw new UnsupportedError("Not supported");
@@ -2947,7 +2948,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGLVertexArrayObjectOES")
-class VertexArrayObjectOes extends Interceptor {
+class VertexArrayObjectOes extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory VertexArrayObjectOes._() {
     throw new UnsupportedError("Not supported");
@@ -4161,7 +4162,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("WebGL2RenderingContextBase")
-abstract class _WebGL2RenderingContextBase extends Interceptor
+abstract class _WebGL2RenderingContextBase extends JavaScriptObject
     implements _WebGLRenderingContextBase {
   // To suppress missing implicit constructor warnings.
   factory _WebGL2RenderingContextBase._() {
@@ -4174,7 +4175,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-abstract class _WebGLRenderingContextBase extends Interceptor {
+abstract class _WebGLRenderingContextBase extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory _WebGLRenderingContextBase._() {
     throw new UnsupportedError("Not supported");
diff --git a/sdk/lib/web_sql/dart2js/web_sql_dart2js.dart b/sdk/lib/web_sql/dart2js/web_sql_dart2js.dart
index 863ba21..584b15a 100644
--- a/sdk/lib/web_sql/dart2js/web_sql_dart2js.dart
+++ b/sdk/lib/web_sql/dart2js/web_sql_dart2js.dart
@@ -19,7 +19,7 @@
 import 'dart:html';
 import 'dart:html_common';
 import 'dart:_foreign_helper' show JS;
-import 'dart:_interceptors' show Interceptor;
+import 'dart:_interceptors' show JavaScriptObject;
 // DO NOT EDIT - unless you are editing documentation as per:
 // https://code.google.com/p/dart/wiki/ContributingHTMLDocumentation
 // Auto-generated dart:audio library.
@@ -72,7 +72,7 @@
 @SupportedBrowser(SupportedBrowser.CHROME)
 @SupportedBrowser(SupportedBrowser.SAFARI)
 @Native("Database")
-class SqlDatabase extends Interceptor {
+class SqlDatabase extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory SqlDatabase._() {
     throw new UnsupportedError("Not supported");
@@ -165,7 +165,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("SQLError")
-class SqlError extends Interceptor {
+class SqlError extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory SqlError._() {
     throw new UnsupportedError("Not supported");
@@ -196,7 +196,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("SQLResultSet")
-class SqlResultSet extends Interceptor {
+class SqlResultSet extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory SqlResultSet._() {
     throw new UnsupportedError("Not supported");
@@ -213,7 +213,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 @Native("SQLResultSetRowList")
-class SqlResultSetRowList extends Interceptor
+class SqlResultSetRowList extends JavaScriptObject
     with ListMixin<Map>, ImmutableListMixin<Map>
     implements List<Map> {
   // To suppress missing implicit constructor warnings.
@@ -282,7 +282,7 @@
 // http://www.w3.org/TR/webdatabase/#sqltransaction
 @deprecated // deprecated
 @Native("SQLTransaction")
-class SqlTransaction extends Interceptor {
+class SqlTransaction extends JavaScriptObject {
   // To suppress missing implicit constructor warnings.
   factory SqlTransaction._() {
     throw new UnsupportedError("Not supported");
diff --git a/tests/co19/co19-dart2js.status b/tests/co19/co19-dart2js.status
index 2073134..277a778 100644
--- a/tests/co19/co19-dart2js.status
+++ b/tests/co19/co19-dart2js.status
@@ -54,8 +54,6 @@
 LibTest/core/int/parse_A01_t02: SkipByDesign # uses integer literal not representable as JavaScript number
 LibTest/core/int/remainder_A01_t03: SkipByDesign # Division by zero is not an error in JavaScript
 LibTest/ffi/*: SkipByDesign # dart:ffi is not supported
-LibTest/html/HttpRequest/responseText_A01_t02: Skip # https://github.com/dart-lang/co19/issues/932
-LibTest/html/HttpRequestUpload/*: Skip # https://github.com/dart-lang/co19/issues/932
 LibTest/io/*: SkipByDesign # dart:io not supported.
 LibTest/isolate/*: SkipByDesign # dart:isolate not supported.
 LibTest/mirrors/*: SkipByDesign # dart:mirrors is not supported
diff --git a/tests/co19/co19-dartdevc.status b/tests/co19/co19-dartdevc.status
index 7e761f2..3458c5c 100644
--- a/tests/co19/co19-dartdevc.status
+++ b/tests/co19/co19-dartdevc.status
@@ -50,8 +50,6 @@
 LibTest/core/int/parse_A01_t02: SkipByDesign # big integers cannot be represented in JavaScript
 LibTest/core/int/remainder_A01_t03: SkipByDesign # Division by zero is not an error in JavaScript
 LibTest/ffi/*: SkipByDesign # dart:ffi is not supported
-LibTest/html/HttpRequest/responseText_A01_t02: Skip # https://github.com/dart-lang/co19/issues/932
-LibTest/html/HttpRequestUpload/*: Skip # https://github.com/dart-lang/co19/issues/932
 LibTest/io/*: SkipByDesign # dart:io not supported.
 LibTest/isolate/*: SkipByDesign # dart:isolate not supported.
 LibTest/mirrors/*: SkipByDesign # dart:mirrors is not supported
diff --git a/tests/ffi/abi_specific_int_incomplete_aot_test.dart b/tests/ffi/abi_specific_int_incomplete_aot_test.dart
new file mode 100644
index 0000000..0b77d43
--- /dev/null
+++ b/tests/ffi/abi_specific_int_incomplete_aot_test.dart
@@ -0,0 +1,23 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// SharedObjects=ffi_test_functions
+
+import 'dart:ffi';
+
+// We want at least 1 mapping to satisfy the static checks.
+const notTestingOn = Abi.fuchsiaArm64;
+
+@AbiSpecificIntegerMapping({
+  notTestingOn: Int8(),
+})
+class Incomplete extends AbiSpecificInteger {
+  const Incomplete();
+}
+
+void main() {
+  // Any use that causes the class to be used, causes a compile-time error
+  // during loading of the class.
+  nullptr.cast<Incomplete>(); //# 1: compile-time error
+}
diff --git a/tests/ffi/abi_specific_int_incomplete_jit_test.dart b/tests/ffi/abi_specific_int_incomplete_jit_test.dart
new file mode 100644
index 0000000..2ecb4c9
--- /dev/null
+++ b/tests/ffi/abi_specific_int_incomplete_jit_test.dart
@@ -0,0 +1,160 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// SharedObjects=ffi_test_functions
+
+import 'dart:ffi';
+
+import 'package:expect/expect.dart';
+import 'package:ffi/ffi.dart';
+
+// We want at least 1 mapping to satisfy the static checks.
+const notTestingOn = Abi.fuchsiaArm64;
+
+@AbiSpecificIntegerMapping({
+  notTestingOn: Int8(),
+})
+class Incomplete extends AbiSpecificInteger {
+  const Incomplete();
+}
+
+void main() {
+  if (Abi.current() == notTestingOn) {
+    return;
+  }
+  testSizeOf();
+  testStoreLoad();
+  testStoreLoadIndexed();
+  testStruct();
+  testInlineArray();
+  testInlineArray2();
+  testAsFunction();
+  testFromFunction();
+}
+
+void testSizeOf() {
+  Expect.throws(() {
+    sizeOf<Incomplete>();
+  });
+}
+
+void testStoreLoad() {
+  final p = calloc<Int64>().cast<Incomplete>();
+  Expect.throws(() {
+    p.value = 10;
+  });
+  Expect.throws(() {
+    p.value;
+  });
+  calloc.free(p);
+}
+
+void testStoreLoadIndexed() {
+  final p = calloc<Int64>().cast<Incomplete>();
+  Expect.throws(() {
+    p[0] = 10;
+  });
+  Expect.throws(() {
+    p[1];
+  });
+  calloc.free(p);
+}
+
+class IncompleteStruct extends Struct {
+  @Incomplete()
+  external int a0;
+
+  @Incomplete()
+  external int a1;
+}
+
+void testStruct() {
+  final p = calloc<Int64>(2).cast<IncompleteStruct>();
+  Expect.throws(() {
+    p.ref.a0 = 1;
+  });
+  Expect.throws(() {
+    p.ref.a0;
+  });
+  calloc.free(p);
+}
+
+class IncompleteArrayStruct extends Struct {
+  @Array(100)
+  external Array<Incomplete> a0;
+}
+
+void testInlineArray() {
+  final p = calloc<Int64>(100).cast<IncompleteArrayStruct>();
+  final array = p.ref.a0;
+  Expect.throws(() {
+    array[3] = 4;
+  });
+  Expect.throws(() {
+    array[3];
+  });
+  calloc.free(p);
+}
+
+const _dim1 = 8;
+const _dim2 = 4;
+
+class IncompleteArrayArrayStruct extends Struct {
+  @Array(_dim1, _dim2)
+  external Array<Array<Incomplete>> a0;
+}
+
+void testInlineArray2() {
+  final p = calloc<Int64>(100).cast<IncompleteArrayArrayStruct>();
+  Expect.throws(() {
+    p.elementAt(3);
+  });
+  calloc.free(p);
+}
+
+void testAsFunction() {
+  Expect.throws(() {
+    nullptr
+        .cast<NativeFunction<Int32 Function(Incomplete)>>()
+        .asFunction<int Function(int)>();
+  });
+  Expect.throws(() {
+    nullptr
+        .cast<NativeFunction<Incomplete Function(Int32)>>()
+        .asFunction<int Function(int)>();
+  });
+  Expect.throws(() {
+    nullptr
+        .cast<NativeFunction<Int32 Function(IncompleteArrayStruct)>>()
+        .asFunction<int Function(IncompleteArrayStruct)>();
+  });
+  Expect.throws(() {
+    nullptr
+        .cast<NativeFunction<IncompleteArrayStruct Function()>>()
+        .asFunction<IncompleteArrayStruct Function()>();
+  });
+}
+
+int myIncr(int a) => a + 1;
+
+IncompleteArrayStruct myIncompleteReturn() =>
+    nullptr.cast<IncompleteArrayStruct>().ref;
+
+int myIncompleteArg(IncompleteArrayStruct a) => 5;
+
+void testFromFunction() {
+  Expect.throws(() {
+    Pointer.fromFunction<Incomplete Function(Int32)>(myIncr, 3);
+  });
+  Expect.throws(() {
+    Pointer.fromFunction<Int32 Function(Incomplete)>(myIncr, 3);
+  });
+  Expect.throws(() {
+    Pointer.fromFunction<IncompleteArrayStruct Function()>(myIncompleteReturn);
+  });
+  Expect.throws(() {
+    Pointer.fromFunction<Int32 Function(IncompleteArrayStruct)>(
+        myIncompleteArg, 3);
+  });
+}
diff --git a/tests/ffi/abi_specific_int_test.dart b/tests/ffi/abi_specific_int_test.dart
new file mode 100644
index 0000000..266655c
--- /dev/null
+++ b/tests/ffi/abi_specific_int_test.dart
@@ -0,0 +1,112 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:ffi';
+import 'dart:io';
+
+import 'package:expect/expect.dart';
+import 'package:ffi/ffi.dart';
+
+import 'abi_specific_ints.dart';
+
+void main() {
+  testSizeOf();
+  testStoreLoad();
+  testStoreLoadIndexed();
+  testStruct();
+  testInlineArray();
+  testInlineArray2();
+}
+
+void testSizeOf() {
+  final size = sizeOf<WChar>();
+  if (Platform.isWindows) {
+    Expect.equals(2, size);
+  } else {
+    Expect.equals(4, size);
+  }
+}
+
+void testStoreLoad() {
+  final p = calloc<WChar>();
+  p.value = 10;
+  Expect.equals(10, p.value);
+  calloc.free(p);
+}
+
+void testStoreLoadIndexed() {
+  final p = calloc<WChar>(2);
+  p[0] = 10;
+  p[1] = 3;
+  Expect.equals(10, p[0]);
+  Expect.equals(3, p[1]);
+  calloc.free(p);
+}
+
+class WCharStruct extends Struct {
+  @WChar()
+  external int a0;
+
+  @WChar()
+  external int a1;
+}
+
+void testStruct() {
+  final p = calloc<WCharStruct>();
+  p.ref.a0 = 1;
+  Expect.equals(1, p.ref.a0);
+  p.ref.a0 = 2;
+  Expect.equals(2, p.ref.a0);
+  calloc.free(p);
+}
+
+class WCharArrayStruct extends Struct {
+  @Array(100)
+  external Array<WChar> a0;
+}
+
+void testInlineArray() {
+  final p = calloc<WCharArrayStruct>();
+  final array = p.ref.a0;
+  for (int i = 0; i < 100; i++) {
+    array[i] = i;
+  }
+  for (int i = 0; i < 100; i++) {
+    Expect.equals(i, array[i]);
+  }
+  calloc.free(p);
+}
+
+const _dim0 = 3;
+const _dim1 = 8;
+const _dim2 = 4;
+
+class WCharArrayArrayStruct extends Struct {
+  @Array(_dim1, _dim2)
+  external Array<Array<WChar>> a0;
+}
+
+void testInlineArray2() {
+  int someValue(int a, int b, int c) => a * 1337 + b * 42 + c;
+  final p = calloc<WCharArrayArrayStruct>(_dim0);
+  for (int i0 = 0; i0 < _dim0; i0++) {
+    final array = p.elementAt(i0).ref.a0;
+    for (int i1 = 0; i1 < _dim1; i1++) {
+      final array2 = array[i1];
+      for (int i2 = 0; i2 < _dim2; i2++) {
+        array2[i2] = someValue(i0, i1, i2);
+      }
+    }
+  }
+  for (int i0 = 0; i0 < _dim0; i0++) {
+    final array = p.elementAt(i0).ref.a0;
+    for (int i1 = 0; i1 < _dim1; i1++) {
+      final array2 = array[i1];
+      for (int i2 = 0; i2 < _dim2; i2++) {
+        Expect.equals(someValue(i0, i1, i2), array2[i2]);
+      }
+    }
+  }
+  calloc.free(p);
+}
diff --git a/tests/ffi/abi_specific_ints.dart b/tests/ffi/abi_specific_ints.dart
new file mode 100644
index 0000000..94e05a4
--- /dev/null
+++ b/tests/ffi/abi_specific_ints.dart
@@ -0,0 +1,137 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:ffi';
+
+// TODO(dacoharkes): These should move to `package:ffi`.
+
+// `int` in C.
+typedef Int = Int32;
+
+// `unsigned int` in C.
+typedef UnsignedInt = Uint32;
+
+// `size_t` in C.
+typedef Size = UintPtr;
+
+// `ssize_t` in C.
+typedef SSize = IntPtr;
+
+// `off_t` in C.
+typedef Off = Long;
+
+/// Represents a native unsigned pointer-sized integer in C.
+///
+/// [UintPtr] is not constructible in the Dart code and serves purely as marker in
+/// type signatures.
+@AbiSpecificIntegerMapping({
+  Abi.androidArm: Uint32(),
+  Abi.androidArm64: Uint64(),
+  Abi.androidIA32: Uint32(),
+  Abi.androidX64: Uint64(),
+  Abi.fuchsiaArm64: Uint64(),
+  Abi.fuchsiaX64: Uint64(),
+  Abi.iosArm: Uint32(),
+  Abi.iosArm64: Uint64(),
+  Abi.iosX64: Uint64(),
+  Abi.linuxArm: Uint32(),
+  Abi.linuxArm64: Uint64(),
+  Abi.linuxIA32: Uint32(),
+  Abi.linuxX64: Uint64(),
+  Abi.macosArm64: Uint64(),
+  Abi.macosX64: Uint64(),
+  Abi.windowsArm64: Uint64(),
+  Abi.windowsIA32: Uint32(),
+  Abi.windowsX64: Uint64(),
+})
+class UintPtr extends AbiSpecificInteger {
+  const UintPtr();
+}
+
+/// `long` in C.
+///
+/// [Long] is not constructible in the Dart code and serves purely as marker in
+/// type signatures.
+@AbiSpecificIntegerMapping({
+  Abi.androidArm: Int32(),
+  Abi.androidArm64: Int64(),
+  Abi.androidIA32: Int32(),
+  Abi.androidX64: Int64(),
+  Abi.fuchsiaArm64: Int64(),
+  Abi.fuchsiaX64: Int64(),
+  Abi.iosArm: Int32(),
+  Abi.iosArm64: Int64(),
+  Abi.iosX64: Int64(),
+  Abi.linuxArm: Int32(),
+  Abi.linuxArm64: Int64(),
+  Abi.linuxIA32: Int32(),
+  Abi.linuxX64: Int64(),
+  Abi.macosArm64: Int64(),
+  Abi.macosX64: Int64(),
+  Abi.windowsArm64: Int32(),
+  Abi.windowsIA32: Int32(),
+  Abi.windowsX64: Int32(),
+})
+class Long extends AbiSpecificInteger {
+  const Long();
+}
+
+/// `unsigned long` in C.
+///
+/// [UnsignedLong] is not constructible in the Dart code and serves purely as marker in
+/// type signatures.
+@AbiSpecificIntegerMapping({
+  Abi.androidArm: Uint32(),
+  Abi.androidArm64: Uint64(),
+  Abi.androidIA32: Uint32(),
+  Abi.androidX64: Uint64(),
+  Abi.fuchsiaArm64: Uint64(),
+  Abi.fuchsiaX64: Uint64(),
+  Abi.iosArm: Uint32(),
+  Abi.iosArm64: Uint64(),
+  Abi.iosX64: Uint64(),
+  Abi.linuxArm: Uint32(),
+  Abi.linuxArm64: Uint64(),
+  Abi.linuxIA32: Uint32(),
+  Abi.linuxX64: Uint64(),
+  Abi.macosArm64: Uint64(),
+  Abi.macosX64: Uint64(),
+  Abi.windowsArm64: Uint32(),
+  Abi.windowsIA32: Uint32(),
+  Abi.windowsX64: Uint32(),
+})
+class UnsignedLong extends AbiSpecificInteger {
+  const UnsignedLong();
+}
+
+/// `wchar_t` in C.
+///
+/// The signedness of `wchar_t` is undefined in C. Here, it is exposed as an
+/// unsigned integer.
+///
+/// [WChar] is not constructible in the Dart code and serves purely as marker in
+/// type signatures.
+@AbiSpecificIntegerMapping({
+  Abi.androidArm: Uint32(),
+  Abi.androidArm64: Uint32(),
+  Abi.androidIA32: Uint32(),
+  Abi.androidX64: Uint32(),
+  Abi.fuchsiaArm64: Uint32(),
+  Abi.fuchsiaX64: Uint32(),
+  Abi.iosArm: Uint32(),
+  Abi.iosArm64: Uint32(),
+  Abi.iosX64: Uint32(),
+  Abi.linuxArm: Uint32(),
+  Abi.linuxArm64: Uint32(),
+  Abi.linuxIA32: Uint32(),
+  Abi.linuxX64: Uint32(),
+  Abi.macosArm64: Uint32(),
+  Abi.macosX64: Uint32(),
+  Abi.windowsArm64: Uint16(),
+  Abi.windowsIA32: Uint16(),
+  Abi.windowsX64: Uint16(),
+})
+class WChar extends AbiSpecificInteger {
+  const WChar();
+}
diff --git a/tests/ffi/c_types_test.dart b/tests/ffi/c_types_test.dart
new file mode 100644
index 0000000..d423c2c
--- /dev/null
+++ b/tests/ffi/c_types_test.dart
@@ -0,0 +1,134 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+//
+// Tests the sizes of c types from https://dartbug.com/36140.
+//
+// SharedObjects=ffi_test_functions
+
+import 'dart:ffi';
+
+import "package:expect/expect.dart";
+import 'dart:io' show Platform;
+
+import 'abi_specific_ints.dart';
+import 'ffi_test_helpers.dart';
+
+void main() {
+  printSizes();
+  testSizes();
+  testIntAssumptions();
+  testSizeTAssumptions();
+  testLongAssumptions();
+  testOffTAssumptions();
+  testWCharTAssumptions();
+}
+
+class CType {
+  final int ffiSize;
+  final String modifier;
+  final String type;
+
+  CType(this.ffiSize, this.type, [this.modifier = ""]);
+
+  String get cRepresentation => "$modifier $type".trim();
+
+  String get _getSizeName => "FfiSizeOf_$modifier\_$type";
+
+  int Function() get sizeFunction => ffiTestFunctions
+      .lookupFunction<Uint64 Function(), int Function()>(_getSizeName);
+
+  int get size => sizeFunction();
+
+  String toString() => cRepresentation;
+}
+
+final intptr_t = CType(sizeOf<IntPtr>(), "intptr_t");
+final uintptr_t = CType(sizeOf<UintPtr>(), "uintptr_t");
+final int_ = CType(sizeOf<Int>(), "int");
+final uint = CType(sizeOf<UnsignedInt>(), "int", "unsigned");
+final long = CType(sizeOf<Long>(), "long");
+final ulong = CType(sizeOf<UnsignedLong>(), "long", "unsigned");
+final wchar_t = CType(sizeOf<WChar>(), "wchar_t");
+final size_t = CType(sizeOf<Size>(), "size_t");
+final ssize_t = CType(sizeOf<SSize>(), "ssize_t");
+final off_t = CType(sizeOf<Off>(), "off_t");
+
+final cTypes = [
+  intptr_t,
+  uintptr_t,
+  int_,
+  uint,
+  long,
+  ulong,
+  wchar_t,
+  size_t,
+  ssize_t,
+  off_t
+];
+
+void printSizes() {
+  cTypes.forEach((element) {
+    print("${element.cRepresentation.padRight(20)}: ${element.size}");
+  });
+}
+
+void testSizes() {
+  cTypes.forEach((element) {
+    Expect.equals(element.size, element.ffiSize);
+  });
+}
+
+void testIntAssumptions() {
+  Expect.equals(4, int_.size);
+  Expect.equals(4, uint.size);
+}
+
+void testSizeTAssumptions() {
+  Expect.equals(intptr_t.size, size_t.size);
+  Expect.equals(intptr_t.size, ssize_t.size);
+}
+
+void testLongAssumptions() {
+  if (Platform.isWindows) {
+    Expect.equals(4, long.size);
+    Expect.equals(4, ulong.size);
+  } else {
+    Expect.equals(intptr_t.size, long.size);
+    Expect.equals(intptr_t.size, ulong.size);
+  }
+}
+
+void testOffTAssumptions() {
+  Expect.equals(long.size, off_t.size);
+}
+
+void testWCharTAssumptions() {
+  final bool isSigned = wCharMinValue() != 0;
+  print("wchar_t isSigned $isSigned");
+  if (Platform.isWindows) {
+    Expect.equals(2, wchar_t.size);
+    if (isSigned) {
+      Expect.equals(-0x8000, wCharMinValue());
+      Expect.equals(0x7fff, wCharMaxValue());
+    } else {
+      Expect.equals(0, wCharMinValue());
+      Expect.equals(0xffff, wCharMaxValue());
+    }
+  } else {
+    Expect.equals(4, wchar_t.size);
+    if (isSigned) {
+      Expect.equals(-0x80000000, wCharMinValue());
+      Expect.equals(0x7fffffff, wCharMaxValue());
+    } else {
+      Expect.equals(0, wCharMinValue());
+      Expect.equals(0xffffffff, wCharMaxValue());
+    }
+  }
+}
+
+int Function() wCharMinValue = ffiTestFunctions
+    .lookupFunction<Uint64 Function(), int Function()>('WCharMinValue');
+
+int Function() wCharMaxValue = ffiTestFunctions
+    .lookupFunction<Uint64 Function(), int Function()>('WCharMaxValue');
diff --git a/tests/ffi/ffi.status b/tests/ffi/ffi.status
index 82ef75c..b119eb8 100644
--- a/tests/ffi/ffi.status
+++ b/tests/ffi/ffi.status
@@ -47,3 +47,9 @@
 
 [ $compiler == dart2analyzer || $compiler == fasta ]
 vmspecific_enable_ffi_test: SkipByDesign # This is a check for VM only.
+
+[ $compiler == dartkp || $arch == arm64 && $system == fuchsia ]
+abi_specific_int_incomplete_jit_test: SkipByDesign # Only intended to run in JIT mode.
+
+[ $compiler != dartkp || $arch == arm64 && $system == fuchsia ]
+abi_specific_int_incomplete_aot_test: SkipByDesign # Only intended to run in AOT mode.
diff --git a/tests/ffi/function_callbacks_structs_by_value_generated_test.dart b/tests/ffi/function_callbacks_structs_by_value_generated_test.dart
index 232b7a5..2276d2f 100644
--- a/tests/ffi/function_callbacks_structs_by_value_generated_test.dart
+++ b/tests/ffi/function_callbacks_structs_by_value_generated_test.dart
@@ -16,6 +16,9 @@
 import "package:expect/expect.dart";
 import "package:ffi/ffi.dart";
 
+// Reuse the AbiSpecificInts.
+import 'abi_specific_ints.dart';
+
 import 'callback_tests_utils.dart';
 
 import 'dylib_utils.dart';
@@ -366,6 +369,12 @@
           passUint8Struct1ByteBool, false),
       passUint8Struct1ByteBoolAfterCallback),
   CallbackTest.withCheck(
+      "PassWCharStructInlineArrayIntUintPtrx2LongUnsigned",
+      Pointer.fromFunction<
+              PassWCharStructInlineArrayIntUintPtrx2LongUnsignedType>(
+          passWCharStructInlineArrayIntUintPtrx2LongUnsigned, 0),
+      passWCharStructInlineArrayIntUintPtrx2LongUnsignedAfterCallback),
+  CallbackTest.withCheck(
       "ReturnStruct1ByteInt",
       Pointer.fromFunction<ReturnStruct1ByteIntType>(returnStruct1ByteInt),
       returnStruct1ByteIntAfterCallback),
@@ -7891,6 +7900,84 @@
   Expect.equals(1 % 2 != 0, result);
 }
 
+typedef PassWCharStructInlineArrayIntUintPtrx2LongUnsignedType = WChar Function(
+    WChar, StructInlineArrayInt, UintPtr, UintPtr, Long, UnsignedLong);
+
+// Global variables to be able to test inputs after callback returned.
+int passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a0 = 0;
+StructInlineArrayInt passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1 =
+    Pointer<StructInlineArrayInt>.fromAddress(0).ref;
+int passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a2 = 0;
+int passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a3 = 0;
+int passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a4 = 0;
+int passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a5 = 0;
+
+// Result variable also global, so we can delete it after the callback.
+int passWCharStructInlineArrayIntUintPtrx2LongUnsignedResult = 0;
+
+int passWCharStructInlineArrayIntUintPtrx2LongUnsignedCalculateResult() {
+  int result = 0;
+
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a0;
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[0];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[1];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[2];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[3];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[4];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[5];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[6];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[7];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[8];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[9];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a2;
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a3;
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a4;
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a5;
+
+  passWCharStructInlineArrayIntUintPtrx2LongUnsignedResult = result;
+
+  return result;
+}
+
+/// Returning a wchar.
+int passWCharStructInlineArrayIntUintPtrx2LongUnsigned(
+    int a0, StructInlineArrayInt a1, int a2, int a3, int a4, int a5) {
+  print(
+      "passWCharStructInlineArrayIntUintPtrx2LongUnsigned(${a0}, ${a1}, ${a2}, ${a3}, ${a4}, ${a5})");
+
+  // In legacy mode, possibly return null.
+
+  // In both nnbd and legacy mode, possibly throw.
+  if (a0 == 42 || a0 == 84) {
+    print("throwing!");
+    throw Exception(
+        "PassWCharStructInlineArrayIntUintPtrx2LongUnsigned throwing on purpose!");
+  }
+
+  passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a0 = a0;
+  passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1 = a1;
+  passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a2 = a2;
+  passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a3 = a3;
+  passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a4 = a4;
+  passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a5 = a5;
+
+  final result =
+      passWCharStructInlineArrayIntUintPtrx2LongUnsignedCalculateResult();
+
+  print("result = $result");
+
+  return result;
+}
+
+void passWCharStructInlineArrayIntUintPtrx2LongUnsignedAfterCallback() {
+  final result =
+      passWCharStructInlineArrayIntUintPtrx2LongUnsignedCalculateResult();
+
+  print("after callback result = $result");
+
+  Expect.equals(120, result);
+}
+
 typedef ReturnStruct1ByteIntType = Struct1ByteInt Function(Int8);
 
 // Global variables to be able to test inputs after callback returned.
diff --git a/tests/ffi/function_structs_by_value_generated_compounds.dart b/tests/ffi/function_structs_by_value_generated_compounds.dart
index 2f41b75..439e9a34 100644
--- a/tests/ffi/function_structs_by_value_generated_compounds.dart
+++ b/tests/ffi/function_structs_by_value_generated_compounds.dart
@@ -7,6 +7,9 @@
 
 import 'dart:ffi';
 
+// Reuse the AbiSpecificInts.
+import 'abi_specific_ints.dart';
+
 class Struct1ByteBool extends Struct {
   @Bool()
   external bool a0;
@@ -1257,3 +1260,10 @@
 
   String toString() => "(${a0}, ${a1}, ${a2})";
 }
+
+class StructInlineArrayInt extends Struct {
+  @Array(10)
+  external Array<WChar> a0;
+
+  String toString() => "(${[for (var i0 = 0; i0 < 10; i0 += 1) a0[i0]]})";
+}
diff --git a/tests/ffi/function_structs_by_value_generated_leaf_test.dart b/tests/ffi/function_structs_by_value_generated_leaf_test.dart
index 2067463..283faad 100644
--- a/tests/ffi/function_structs_by_value_generated_leaf_test.dart
+++ b/tests/ffi/function_structs_by_value_generated_leaf_test.dart
@@ -16,6 +16,9 @@
 import "package:expect/expect.dart";
 import "package:ffi/ffi.dart";
 
+// Reuse the AbiSpecificInts.
+import 'abi_specific_ints.dart';
+
 import 'dylib_utils.dart';
 
 // Reuse the compound classes.
@@ -89,6 +92,7 @@
     testPassUint8Boolx9Struct10BytesHomogeneousBoolBoolLeaf();
     testPassUint8Boolx9Struct10BytesInlineArrayBoolBoolLeaf();
     testPassUint8Struct1ByteBoolLeaf();
+    testPassWCharStructInlineArrayIntUintPtrx2LongUnsignedLeaf();
     testReturnStruct1ByteIntLeaf();
     testReturnStruct3BytesHomogeneousUint8Leaf();
     testReturnStruct3BytesInt2ByteAlignedLeaf();
@@ -5461,6 +5465,50 @@
   calloc.free(a1Pointer);
 }
 
+final passWCharStructInlineArrayIntUintPtrx2LongUnsignedLeaf = ffiTestFunctions
+    .lookupFunction<
+            WChar Function(WChar, StructInlineArrayInt, UintPtr, UintPtr, Long,
+                UnsignedLong),
+            int Function(int, StructInlineArrayInt, int, int, int, int)>(
+        "PassWCharStructInlineArrayIntUintPtrx2LongUnsigned",
+        isLeaf: true);
+
+/// Returning a wchar.
+void testPassWCharStructInlineArrayIntUintPtrx2LongUnsignedLeaf() {
+  int a0;
+  final a1Pointer = calloc<StructInlineArrayInt>();
+  final StructInlineArrayInt a1 = a1Pointer.ref;
+  int a2;
+  int a3;
+  int a4;
+  int a5;
+
+  a0 = 1;
+  a1.a0[0] = 2;
+  a1.a0[1] = 3;
+  a1.a0[2] = 4;
+  a1.a0[3] = 5;
+  a1.a0[4] = 6;
+  a1.a0[5] = 7;
+  a1.a0[6] = 8;
+  a1.a0[7] = 9;
+  a1.a0[8] = 10;
+  a1.a0[9] = 11;
+  a2 = 12;
+  a3 = 13;
+  a4 = 14;
+  a5 = 15;
+
+  final result = passWCharStructInlineArrayIntUintPtrx2LongUnsignedLeaf(
+      a0, a1, a2, a3, a4, a5);
+
+  print("result = $result");
+
+  Expect.equals(120, result);
+
+  calloc.free(a1Pointer);
+}
+
 final returnStruct1ByteIntLeaf = ffiTestFunctions.lookupFunction<
     Struct1ByteInt Function(Int8),
     Struct1ByteInt Function(int)>("ReturnStruct1ByteInt", isLeaf: true);
diff --git a/tests/ffi/function_structs_by_value_generated_test.dart b/tests/ffi/function_structs_by_value_generated_test.dart
index 463118d..1f4c5d3 100644
--- a/tests/ffi/function_structs_by_value_generated_test.dart
+++ b/tests/ffi/function_structs_by_value_generated_test.dart
@@ -16,6 +16,9 @@
 import "package:expect/expect.dart";
 import "package:ffi/ffi.dart";
 
+// Reuse the AbiSpecificInts.
+import 'abi_specific_ints.dart';
+
 import 'dylib_utils.dart';
 
 // Reuse the compound classes.
@@ -89,6 +92,7 @@
     testPassUint8Boolx9Struct10BytesHomogeneousBoolBool();
     testPassUint8Boolx9Struct10BytesInlineArrayBoolBool();
     testPassUint8Struct1ByteBool();
+    testPassWCharStructInlineArrayIntUintPtrx2LongUnsigned();
     testReturnStruct1ByteInt();
     testReturnStruct3BytesHomogeneousUint8();
     testReturnStruct3BytesInt2ByteAligned();
@@ -5385,6 +5389,49 @@
   calloc.free(a1Pointer);
 }
 
+final passWCharStructInlineArrayIntUintPtrx2LongUnsigned =
+    ffiTestFunctions.lookupFunction<
+        WChar Function(
+            WChar, StructInlineArrayInt, UintPtr, UintPtr, Long, UnsignedLong),
+        int Function(int, StructInlineArrayInt, int, int, int,
+            int)>("PassWCharStructInlineArrayIntUintPtrx2LongUnsigned");
+
+/// Returning a wchar.
+void testPassWCharStructInlineArrayIntUintPtrx2LongUnsigned() {
+  int a0;
+  final a1Pointer = calloc<StructInlineArrayInt>();
+  final StructInlineArrayInt a1 = a1Pointer.ref;
+  int a2;
+  int a3;
+  int a4;
+  int a5;
+
+  a0 = 1;
+  a1.a0[0] = 2;
+  a1.a0[1] = 3;
+  a1.a0[2] = 4;
+  a1.a0[3] = 5;
+  a1.a0[4] = 6;
+  a1.a0[5] = 7;
+  a1.a0[6] = 8;
+  a1.a0[7] = 9;
+  a1.a0[8] = 10;
+  a1.a0[9] = 11;
+  a2 = 12;
+  a3 = 13;
+  a4 = 14;
+  a5 = 15;
+
+  final result = passWCharStructInlineArrayIntUintPtrx2LongUnsigned(
+      a0, a1, a2, a3, a4, a5);
+
+  print("result = $result");
+
+  Expect.equals(120, result);
+
+  calloc.free(a1Pointer);
+}
+
 final returnStruct1ByteInt = ffiTestFunctions.lookupFunction<
     Struct1ByteInt Function(Int8),
     Struct1ByteInt Function(int)>("ReturnStruct1ByteInt");
diff --git a/tests/ffi/generator/c_types.dart b/tests/ffi/generator/c_types.dart
index d0825f6..bb92bc4 100644
--- a/tests/ffi/generator/c_types.dart
+++ b/tests/ffi/generator/c_types.dart
@@ -18,6 +18,10 @@
 const intptr = FundamentalType(PrimitiveType.intptr);
 const float = FundamentalType(PrimitiveType.float);
 const double_ = FundamentalType(PrimitiveType.double_);
+const long = FundamentalType(PrimitiveType.long);
+const ulong = FundamentalType(PrimitiveType.ulong);
+const uintptr = FundamentalType(PrimitiveType.uintptr);
+const wchar = FundamentalType(PrimitiveType.wchar);
 
 enum PrimitiveType {
   bool_,
@@ -32,25 +36,96 @@
   intptr,
   float,
   double_,
+  long,
+  ulong,
+  uintptr,
+  wchar,
 }
 
-const primitiveNames = [
-  "bool",
-  "int8",
-  "int16",
-  "int32",
-  "int64",
-  "uint8",
-  "uint16",
-  "uint32",
-  "uint64",
-  "intptr",
-  "float",
-  "double",
-];
+const primitiveNames = {
+  PrimitiveType.bool_: "bool",
+  PrimitiveType.int8: "int8",
+  PrimitiveType.int16: "int16",
+  PrimitiveType.int32: "int32",
+  PrimitiveType.int64: "int64",
+  PrimitiveType.uint8: "uint8",
+  PrimitiveType.uint16: "uint16",
+  PrimitiveType.uint32: "uint32",
+  PrimitiveType.uint64: "uint64",
+  PrimitiveType.intptr: "intptr",
+  PrimitiveType.float: "float",
+  PrimitiveType.double_: "double",
+  PrimitiveType.long: "long",
+  PrimitiveType.ulong: "ulong",
+  PrimitiveType.uintptr: "uintptr",
+  PrimitiveType.wchar: "wchar",
+};
 
-const intptrSize = -1;
-const primitiveSizesInBytes = [1, 1, 2, 4, 8, 1, 2, 4, 8, intptrSize, 4, 8];
+final primitiveCType = {
+  PrimitiveType.bool_: "bool",
+  PrimitiveType.int8: "int8_t",
+  PrimitiveType.int16: "int16_t",
+  PrimitiveType.int32: "int32_t",
+  PrimitiveType.int64: "int64_t",
+  PrimitiveType.uint8: "uint8_t",
+  PrimitiveType.uint16: "uint16_t",
+  PrimitiveType.uint32: "uint32_t",
+  PrimitiveType.uint64: "uint64_t",
+  PrimitiveType.intptr: "intptr",
+  PrimitiveType.float: "float",
+  PrimitiveType.double_: "double",
+  // People should use explicit sizes. But we also want to test `long`.
+  // Surpressing lint.
+  PrimitiveType.long: "/* NOLINT(runtime/int) */long",
+  PrimitiveType.ulong: "/* NOLINT(runtime/int) */unsigned long",
+  PrimitiveType.uintptr: "uintptr_t",
+  PrimitiveType.wchar: "wchar_t",
+};
+
+final primitiveDartCType = {
+  PrimitiveType.bool_: "Bool",
+  PrimitiveType.int8: "Int8",
+  PrimitiveType.int16: "Int16",
+  PrimitiveType.int32: "Int32",
+  PrimitiveType.int64: "Int64",
+  PrimitiveType.uint8: "Uint8",
+  PrimitiveType.uint16: "Uint16",
+  PrimitiveType.uint32: "Uint32",
+  PrimitiveType.uint64: "Uint64",
+  PrimitiveType.intptr: "Intptr",
+  PrimitiveType.float: "Float",
+  PrimitiveType.double_: "Double",
+  PrimitiveType.long: "Long",
+  PrimitiveType.ulong: "UnsignedLong",
+  PrimitiveType.uintptr: "UintPtr",
+  PrimitiveType.wchar: "WChar",
+};
+
+/// Sizes equal on all platforms.
+const primitiveSizesInBytes = {
+  PrimitiveType.bool_: 1,
+  PrimitiveType.int8: 1,
+  PrimitiveType.int16: 2,
+  PrimitiveType.int32: 4,
+  PrimitiveType.int64: 8,
+  PrimitiveType.uint8: 1,
+  PrimitiveType.uint16: 2,
+  PrimitiveType.uint32: 4,
+  PrimitiveType.uint64: 8,
+  PrimitiveType.float: 4,
+  PrimitiveType.double_: 8,
+};
+
+const primitivesUnsigned = {
+  PrimitiveType.bool_,
+  PrimitiveType.uint8,
+  PrimitiveType.uint16,
+  PrimitiveType.uint32,
+  PrimitiveType.uint64,
+  PrimitiveType.uintptr,
+  PrimitiveType.ulong,
+  PrimitiveType.wchar,
+};
 
 abstract class CType {
   String get cType;
@@ -90,18 +165,13 @@
   bool get isOnlyFloatingPoint => isFloatingPoint;
   bool get isOnlyInteger => isInteger;
   bool get isOnlyBool => isBool;
-  bool get isUnsigned =>
-      primitive == PrimitiveType.bool_ ||
-      primitive == PrimitiveType.uint8 ||
-      primitive == PrimitiveType.uint16 ||
-      primitive == PrimitiveType.uint32 ||
-      primitive == PrimitiveType.uint64;
+  bool get isUnsigned => primitivesUnsigned.contains(primitive);
   bool get isSigned => !isUnsigned;
 
-  String get name => primitiveNames[primitive.index];
+  String get name => primitiveNames[primitive]!;
 
-  String get cType => "${name}${isInteger ? "_t" : ""}";
-  String get dartCType => name.upperCaseFirst();
+  String get cType => primitiveCType[primitive]!;
+  String get dartCType => primitiveDartCType[primitive]!;
   String get dartType {
     if (isInteger) return 'int';
     if (isOnlyFloatingPoint) return 'double';
@@ -110,12 +180,12 @@
   }
 
   String get dartStructFieldAnnotation => "@${dartCType}()";
-  bool get hasSize => primitive != PrimitiveType.intptr;
+  bool get hasSize => primitiveSizesInBytes.containsKey(primitive);
   int get size {
     if (!hasSize) {
       throw "Size unknown.";
     }
-    return primitiveSizesInBytes[primitive.index];
+    return primitiveSizesInBytes[primitive]!;
   }
 }
 
diff --git a/tests/ffi/generator/structs_by_value_tests_configuration.dart b/tests/ffi/generator/structs_by_value_tests_configuration.dart
index a5d62af..9179d50 100644
--- a/tests/ffi/generator/structs_by_value_tests_configuration.dart
+++ b/tests/ffi/generator/structs_by_value_tests_configuration.dart
@@ -422,6 +422,18 @@
       bool_,
       """
 Returning a bool."""),
+  FunctionType(
+      [
+        wchar,
+        structArrayWChar,
+        uintptr,
+        uintptr,
+        long,
+        ulong,
+      ],
+      wchar,
+      """
+Returning a wchar."""),
 ];
 
 final functionsStructReturn = [
@@ -672,6 +684,7 @@
   union12bytesInt,
   union16bytesFloat,
   union16bytesFloat2,
+  structArrayWChar,
 ];
 
 final struct1byteBool = StructType([bool_]);
@@ -863,3 +876,6 @@
 /// This union has homogenous floats of different sizes.
 final union16bytesFloat2 =
     UnionType([struct8bytesFloat, struct12bytesFloat, struct16bytesFloat]);
+
+/// This struct contains an AbiSpecificInt type.
+final structArrayWChar = StructType([FixedLengthArrayType(wchar, 10)]);
diff --git a/tests/ffi/generator/structs_by_value_tests_generator.dart b/tests/ffi/generator/structs_by_value_tests_generator.dart
index 51de2db..4c260b9 100644
--- a/tests/ffi/generator/structs_by_value_tests_generator.dart
+++ b/tests/ffi/generator/structs_by_value_tests_generator.dart
@@ -399,7 +399,7 @@
     switch (this.runtimeType) {
       case FundamentalType:
         final this_ = this as FundamentalType;
-        if (this_.isInteger) {
+        if (this_.isInteger || this_.isBool) {
           return "CHECK_EQ(${expected}, ${actual});";
         }
         assert(this_.isFloatingPoint);
@@ -426,7 +426,7 @@
     switch (this.runtimeType) {
       case FundamentalType:
         final this_ = this as FundamentalType;
-        if (this_.isInteger) {
+        if (this_.isInteger || this_.isBool) {
           return "CHECK_EQ(0, ${actual});";
         }
         assert(this_.isFloatingPoint);
@@ -921,6 +921,9 @@
 $dartVersion
 
 import 'dart:ffi';
+
+// Reuse the AbiSpecificInts.
+import 'abi_specific_ints.dart';
 """;
 }
 
@@ -929,7 +932,7 @@
   return Platform.script
       .resolve(
           "../../$folder/function_structs_by_value_generated_compounds.dart")
-      .path;
+      .toFilePath();
 }
 
 Future<void> writeDartCompounds() async {
@@ -964,6 +967,9 @@
 import "package:expect/expect.dart";
 import "package:ffi/ffi.dart";
 
+// Reuse the AbiSpecificInts.
+import 'abi_specific_ints.dart';
+
 import 'dylib_utils.dart';
 
 // Reuse the compound classes.
@@ -1001,7 +1007,7 @@
   return Platform.script
       .resolve(
           "../../$folder/function_structs_by_value_generated${suffix}_test.dart")
-      .path;
+      .toFilePath();
 }
 
 headerDartCallbackTest({required bool isNnbd, required int copyrightYear}) {
@@ -1023,6 +1029,9 @@
 import "package:expect/expect.dart";
 import "package:ffi/ffi.dart";
 
+// Reuse the AbiSpecificInts.
+import 'abi_specific_ints.dart';
+
 import 'callback_tests_utils.dart';
 
 import 'dylib_utils.dart';
@@ -1067,7 +1076,7 @@
   return Platform.script
       .resolve(
           "../../$folder/function_callbacks_structs_by_value_generated_test.dart")
-      .path;
+      .toFilePath();
 }
 
 headerC({required int copyrightYear}) {
@@ -1128,7 +1137,7 @@
 
 final ccPath = Platform.script
     .resolve("../../../runtime/bin/ffi_test/ffi_test_functions_generated.cc")
-    .path;
+    .toFilePath();
 
 void printUsage() {
   print("""
diff --git a/tests/ffi/vmspecific_static_checks_test.dart b/tests/ffi/vmspecific_static_checks_test.dart
index e77b941..ba7f5ab 100644
--- a/tests/ffi/vmspecific_static_checks_test.dart
+++ b/tests/ffi/vmspecific_static_checks_test.dart
@@ -848,3 +848,35 @@
   @Array.multi([2, 2, 2, 2, 2, 2, -1]) //# 1802: compile-time error
   external Array<Uint8> inlineArray; //# 1802: compile-time error
 }
+
+@AbiSpecificIntegerMapping({
+  Abi.androidArm: Uint32(),
+  Abi.androidArm64: IntPtr(), //# 1900: compile-time error
+  Abi.androidIA32: AbiSpecificInteger1(), //# 1901: compile-time error
+})
+@AbiSpecificIntegerMapping({}) //# 1902: compile-time error
+class AbiSpecificInteger1 extends AbiSpecificInteger {
+  const AbiSpecificInteger1();
+
+  int get a => 4; //# 1910: compile-time error
+
+  external int b; //# 1911: compile-time error
+}
+
+class AbiSpecificInteger2
+    implements AbiSpecificInteger //# 1903: compile-time error
+{
+  const AbiSpecificInteger2();
+}
+
+class AbiSpecificInteger3
+    extends AbiSpecificInteger1 //# 1904: compile-time error
+{
+  const AbiSpecificInteger3();
+}
+
+class AbiSpecificInteger4
+    implements AbiSpecificInteger1 //# 1905: compile-time error
+{
+  const AbiSpecificInteger4();
+}
diff --git a/tests/ffi_2/abi_specific_int_incomplete_aot_test.dart b/tests/ffi_2/abi_specific_int_incomplete_aot_test.dart
new file mode 100644
index 0000000..8429652
--- /dev/null
+++ b/tests/ffi_2/abi_specific_int_incomplete_aot_test.dart
@@ -0,0 +1,25 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// @dart = 2.9
+
+// SharedObjects=ffi_test_functions
+
+import 'dart:ffi';
+
+// We want at least 1 mapping to satisfy the static checks.
+const notTestingOn = Abi.fuchsiaArm64;
+
+@AbiSpecificIntegerMapping({
+  notTestingOn: Int8(),
+})
+class Incomplete extends AbiSpecificInteger {
+  const Incomplete();
+}
+
+void main() {
+  // Any use that causes the class to be used, causes a compile-time error
+  // during loading of the class.
+  nullptr.cast<Incomplete>(); //# 1: compile-time error
+}
diff --git a/tests/ffi_2/abi_specific_int_incomplete_jit_test.dart b/tests/ffi_2/abi_specific_int_incomplete_jit_test.dart
new file mode 100644
index 0000000..b507ed9
--- /dev/null
+++ b/tests/ffi_2/abi_specific_int_incomplete_jit_test.dart
@@ -0,0 +1,162 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// @dart = 2.9
+
+// SharedObjects=ffi_test_functions
+
+import 'dart:ffi';
+
+import 'package:expect/expect.dart';
+import 'package:ffi/ffi.dart';
+
+// We want at least 1 mapping to satisfy the static checks.
+const notTestingOn = Abi.fuchsiaArm64;
+
+@AbiSpecificIntegerMapping({
+  notTestingOn: Int8(),
+})
+class Incomplete extends AbiSpecificInteger {
+  const Incomplete();
+}
+
+void main() {
+  if (Abi.current() == notTestingOn) {
+    return;
+  }
+  testSizeOf();
+  testStoreLoad();
+  testStoreLoadIndexed();
+  testStruct();
+  testInlineArray();
+  testInlineArray2();
+  testAsFunction();
+  testFromFunction();
+}
+
+void testSizeOf() {
+  Expect.throws(() {
+    sizeOf<Incomplete>();
+  });
+}
+
+void testStoreLoad() {
+  final p = calloc<Int64>().cast<Incomplete>();
+  Expect.throws(() {
+    p.value = 10;
+  });
+  Expect.throws(() {
+    p.value;
+  });
+  calloc.free(p);
+}
+
+void testStoreLoadIndexed() {
+  final p = calloc<Int64>().cast<Incomplete>();
+  Expect.throws(() {
+    p[0] = 10;
+  });
+  Expect.throws(() {
+    p[1];
+  });
+  calloc.free(p);
+}
+
+class IncompleteStruct extends Struct {
+  @Incomplete()
+  int a0;
+
+  @Incomplete()
+  int a1;
+}
+
+void testStruct() {
+  final p = calloc<Int64>(2).cast<IncompleteStruct>();
+  Expect.throws(() {
+    p.ref.a0 = 1;
+  });
+  Expect.throws(() {
+    p.ref.a0;
+  });
+  calloc.free(p);
+}
+
+class IncompleteArrayStruct extends Struct {
+  @Array(100)
+  Array<Incomplete> a0;
+}
+
+void testInlineArray() {
+  final p = calloc<Int64>(100).cast<IncompleteArrayStruct>();
+  final array = p.ref.a0;
+  Expect.throws(() {
+    array[3] = 4;
+  });
+  Expect.throws(() {
+    array[3];
+  });
+  calloc.free(p);
+}
+
+const _dim1 = 8;
+const _dim2 = 4;
+
+class IncompleteArrayArrayStruct extends Struct {
+  @Array(_dim1, _dim2)
+  Array<Array<Incomplete>> a0;
+}
+
+void testInlineArray2() {
+  final p = calloc<Int64>(100).cast<IncompleteArrayArrayStruct>();
+  Expect.throws(() {
+    p.elementAt(3);
+  });
+  calloc.free(p);
+}
+
+void testAsFunction() {
+  Expect.throws(() {
+    nullptr
+        .cast<NativeFunction<Int32 Function(Incomplete)>>()
+        .asFunction<int Function(int)>();
+  });
+  Expect.throws(() {
+    nullptr
+        .cast<NativeFunction<Incomplete Function(Int32)>>()
+        .asFunction<int Function(int)>();
+  });
+  Expect.throws(() {
+    nullptr
+        .cast<NativeFunction<Int32 Function(IncompleteArrayStruct)>>()
+        .asFunction<int Function(IncompleteArrayStruct)>();
+  });
+  Expect.throws(() {
+    nullptr
+        .cast<NativeFunction<IncompleteArrayStruct Function()>>()
+        .asFunction<IncompleteArrayStruct Function()>();
+  });
+}
+
+int myIncr(int a) => a + 1;
+
+IncompleteArrayStruct myIncompleteReturn() =>
+    nullptr.cast<IncompleteArrayStruct>().ref;
+
+int myIncompleteArg(IncompleteArrayStruct a) => 5;
+
+void testFromFunction() {
+  Expect.throws(() {
+    Pointer.fromFunction<Incomplete Function(Int32)>(myIncr, 3);
+  });
+  Expect.throws(() {
+    Pointer.fromFunction<Int32 Function(Incomplete)>(myIncr, 3);
+  });
+  Expect.throws(() {
+    Pointer.fromFunction<IncompleteArrayStruct Function()>(myIncompleteReturn);
+  });
+  Expect.throws(() {
+    Pointer.fromFunction<Int32 Function(IncompleteArrayStruct)>(
+        myIncompleteArg, 3);
+  });
+}
diff --git a/tests/ffi_2/abi_specific_int_test.dart b/tests/ffi_2/abi_specific_int_test.dart
new file mode 100644
index 0000000..152c159
--- /dev/null
+++ b/tests/ffi_2/abi_specific_int_test.dart
@@ -0,0 +1,114 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// @dart = 2.9
+
+import 'dart:ffi';
+import 'dart:io';
+
+import 'package:expect/expect.dart';
+import 'package:ffi/ffi.dart';
+
+import 'abi_specific_ints.dart';
+
+void main() {
+  testSizeOf();
+  testStoreLoad();
+  testStoreLoadIndexed();
+  testStruct();
+  testInlineArray();
+  testInlineArray2();
+}
+
+void testSizeOf() {
+  final size = sizeOf<WChar>();
+  if (Platform.isWindows) {
+    Expect.equals(2, size);
+  } else {
+    Expect.equals(4, size);
+  }
+}
+
+void testStoreLoad() {
+  final p = calloc<WChar>();
+  p.value = 10;
+  Expect.equals(10, p.value);
+  calloc.free(p);
+}
+
+void testStoreLoadIndexed() {
+  final p = calloc<WChar>(2);
+  p[0] = 10;
+  p[1] = 3;
+  Expect.equals(10, p[0]);
+  Expect.equals(3, p[1]);
+  calloc.free(p);
+}
+
+class WCharStruct extends Struct {
+  @WChar()
+  int a0;
+
+  @WChar()
+  int a1;
+}
+
+void testStruct() {
+  final p = calloc<WCharStruct>();
+  p.ref.a0 = 1;
+  Expect.equals(1, p.ref.a0);
+  p.ref.a0 = 2;
+  Expect.equals(2, p.ref.a0);
+  calloc.free(p);
+}
+
+class WCharArrayStruct extends Struct {
+  @Array(100)
+  Array<WChar> a0;
+}
+
+void testInlineArray() {
+  final p = calloc<WCharArrayStruct>();
+  final array = p.ref.a0;
+  for (int i = 0; i < 100; i++) {
+    array[i] = i;
+  }
+  for (int i = 0; i < 100; i++) {
+    Expect.equals(i, array[i]);
+  }
+  calloc.free(p);
+}
+
+const _dim0 = 3;
+const _dim1 = 8;
+const _dim2 = 4;
+
+class WCharArrayArrayStruct extends Struct {
+  @Array(_dim1, _dim2)
+  Array<Array<WChar>> a0;
+}
+
+void testInlineArray2() {
+  int someValue(int a, int b, int c) => a * 1337 + b * 42 + c;
+  final p = calloc<WCharArrayArrayStruct>(_dim0);
+  for (int i0 = 0; i0 < _dim0; i0++) {
+    final array = p.elementAt(i0).ref.a0;
+    for (int i1 = 0; i1 < _dim1; i1++) {
+      final array2 = array[i1];
+      for (int i2 = 0; i2 < _dim2; i2++) {
+        array2[i2] = someValue(i0, i1, i2);
+      }
+    }
+  }
+  for (int i0 = 0; i0 < _dim0; i0++) {
+    final array = p.elementAt(i0).ref.a0;
+    for (int i1 = 0; i1 < _dim1; i1++) {
+      final array2 = array[i1];
+      for (int i2 = 0; i2 < _dim2; i2++) {
+        Expect.equals(someValue(i0, i1, i2), array2[i2]);
+      }
+    }
+  }
+  calloc.free(p);
+}
diff --git a/tests/ffi_2/abi_specific_ints.dart b/tests/ffi_2/abi_specific_ints.dart
new file mode 100644
index 0000000..91c9875
--- /dev/null
+++ b/tests/ffi_2/abi_specific_ints.dart
@@ -0,0 +1,124 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// @dart = 2.9
+
+import 'dart:ffi';
+
+// TODO(dacoharkes): These should move to `package:ffi`.
+
+/// Represents a native unsigned pointer-sized integer in C.
+///
+/// [UintPtr] is not constructible in the Dart code and serves purely as marker in
+/// type signatures.
+@AbiSpecificIntegerMapping({
+  Abi.androidArm: Uint32(),
+  Abi.androidArm64: Uint64(),
+  Abi.androidIA32: Uint32(),
+  Abi.androidX64: Uint64(),
+  Abi.fuchsiaArm64: Uint64(),
+  Abi.fuchsiaX64: Uint64(),
+  Abi.iosArm: Uint32(),
+  Abi.iosArm64: Uint64(),
+  Abi.iosX64: Uint64(),
+  Abi.linuxArm: Uint32(),
+  Abi.linuxArm64: Uint64(),
+  Abi.linuxIA32: Uint32(),
+  Abi.linuxX64: Uint64(),
+  Abi.macosArm64: Uint64(),
+  Abi.macosX64: Uint64(),
+  Abi.windowsArm64: Uint64(),
+  Abi.windowsIA32: Uint32(),
+  Abi.windowsX64: Uint64(),
+})
+class UintPtr extends AbiSpecificInteger {
+  const UintPtr();
+}
+
+/// `long` in C.
+///
+/// [Long] is not constructible in the Dart code and serves purely as marker in
+/// type signatures.
+@AbiSpecificIntegerMapping({
+  Abi.androidArm: Int32(),
+  Abi.androidArm64: Int64(),
+  Abi.androidIA32: Int32(),
+  Abi.androidX64: Int64(),
+  Abi.fuchsiaArm64: Int64(),
+  Abi.fuchsiaX64: Int64(),
+  Abi.iosArm: Int32(),
+  Abi.iosArm64: Int64(),
+  Abi.iosX64: Int64(),
+  Abi.linuxArm: Int32(),
+  Abi.linuxArm64: Int64(),
+  Abi.linuxIA32: Int32(),
+  Abi.linuxX64: Int64(),
+  Abi.macosArm64: Int64(),
+  Abi.macosX64: Int64(),
+  Abi.windowsArm64: Int32(),
+  Abi.windowsIA32: Int32(),
+  Abi.windowsX64: Int32(),
+})
+class Long extends AbiSpecificInteger {
+  const Long();
+}
+
+/// `unsigned long` in C.
+///
+/// [UnsignedLong] is not constructible in the Dart code and serves purely as marker in
+/// type signatures.
+@AbiSpecificIntegerMapping({
+  Abi.androidArm: Uint32(),
+  Abi.androidArm64: Uint64(),
+  Abi.androidIA32: Uint32(),
+  Abi.androidX64: Uint64(),
+  Abi.fuchsiaArm64: Uint64(),
+  Abi.fuchsiaX64: Uint64(),
+  Abi.iosArm: Uint32(),
+  Abi.iosArm64: Uint64(),
+  Abi.iosX64: Uint64(),
+  Abi.linuxArm: Uint32(),
+  Abi.linuxArm64: Uint64(),
+  Abi.linuxIA32: Uint32(),
+  Abi.linuxX64: Uint64(),
+  Abi.macosArm64: Uint64(),
+  Abi.macosX64: Uint64(),
+  Abi.windowsArm64: Uint32(),
+  Abi.windowsIA32: Uint32(),
+  Abi.windowsX64: Uint32(),
+})
+class UnsignedLong extends AbiSpecificInteger {
+  const UnsignedLong();
+}
+
+/// `wchar_t` in C.
+///
+/// The signedness of `wchar_t` is undefined in C. Here, it is exposed as an
+/// unsigned integer.
+///
+/// [WChar] is not constructible in the Dart code and serves purely as marker in
+/// type signatures.
+@AbiSpecificIntegerMapping({
+  Abi.androidArm: Uint32(),
+  Abi.androidArm64: Uint32(),
+  Abi.androidIA32: Uint32(),
+  Abi.androidX64: Uint32(),
+  Abi.fuchsiaArm64: Uint32(),
+  Abi.fuchsiaX64: Uint32(),
+  Abi.iosArm: Uint32(),
+  Abi.iosArm64: Uint32(),
+  Abi.iosX64: Uint32(),
+  Abi.linuxArm: Uint32(),
+  Abi.linuxArm64: Uint32(),
+  Abi.linuxIA32: Uint32(),
+  Abi.linuxX64: Uint32(),
+  Abi.macosArm64: Uint32(),
+  Abi.macosX64: Uint32(),
+  Abi.windowsArm64: Uint16(),
+  Abi.windowsIA32: Uint16(),
+  Abi.windowsX64: Uint16(),
+})
+class WChar extends AbiSpecificInteger {
+  const WChar();
+}
diff --git a/tests/ffi_2/c_types_test.dart b/tests/ffi_2/c_types_test.dart
new file mode 100644
index 0000000..fa762bd
--- /dev/null
+++ b/tests/ffi_2/c_types_test.dart
@@ -0,0 +1,109 @@
+// Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+//
+// Tests the sizes of c types from https://dartbug.com/36140.
+//
+// SharedObjects=ffi_test_functions
+
+// @dart = 2.9
+
+import 'dart:ffi';
+
+import "package:expect/expect.dart";
+import 'dart:io' show Platform;
+
+import 'abi_specific_ints.dart';
+import 'ffi_test_helpers.dart';
+
+void main() {
+  printSizes();
+  testSizes();
+  testLongAssumptions();
+  testWCharTAssumptions();
+}
+
+class CType {
+  final int ffiSize;
+  final String modifier;
+  final String type;
+
+  CType(this.ffiSize, this.type, [this.modifier = ""]);
+
+  String get cRepresentation => "$modifier $type".trim();
+
+  String get _getSizeName => "FfiSizeOf_$modifier\_$type";
+
+  int Function() get sizeFunction => ffiTestFunctions
+      .lookupFunction<Uint64 Function(), int Function()>(_getSizeName);
+
+  int get size => sizeFunction();
+
+  String toString() => cRepresentation;
+}
+
+final intptr_t = CType(sizeOf<IntPtr>(), "intptr_t");
+final uintptr_t = CType(sizeOf<UintPtr>(), "uintptr_t");
+final long = CType(sizeOf<Long>(), "long");
+final ulong = CType(sizeOf<UnsignedLong>(), "long", "unsigned");
+final wchar_t = CType(sizeOf<WChar>(), "wchar_t");
+
+final cTypes = [
+  intptr_t,
+  uintptr_t,
+  long,
+  ulong,
+  wchar_t,
+];
+
+void printSizes() {
+  cTypes.forEach((element) {
+    print("${element.cRepresentation.padRight(20)}: ${element.size}");
+  });
+}
+
+void testSizes() {
+  cTypes.forEach((element) {
+    Expect.equals(element.size, element.ffiSize);
+  });
+}
+
+void testLongAssumptions() {
+  if (Platform.isWindows) {
+    Expect.equals(4, long.size);
+    Expect.equals(4, ulong.size);
+  } else {
+    Expect.equals(intptr_t.size, long.size);
+    Expect.equals(intptr_t.size, ulong.size);
+  }
+}
+
+void testWCharTAssumptions() {
+  final bool isSigned = wCharMinValue() != 0;
+  print("wchar_t isSigned $isSigned");
+  if (Platform.isWindows) {
+    Expect.equals(2, wchar_t.size);
+    if (isSigned) {
+      Expect.equals(-0x8000, wCharMinValue());
+      Expect.equals(0x7fff, wCharMaxValue());
+    } else {
+      Expect.equals(0, wCharMinValue());
+      Expect.equals(0xffff, wCharMaxValue());
+    }
+  } else {
+    Expect.equals(4, wchar_t.size);
+    if (isSigned) {
+      Expect.equals(-0x80000000, wCharMinValue());
+      Expect.equals(0x7fffffff, wCharMaxValue());
+    } else {
+      Expect.equals(0, wCharMinValue());
+      Expect.equals(0xffffffff, wCharMaxValue());
+    }
+  }
+}
+
+int Function() wCharMinValue = ffiTestFunctions
+    .lookupFunction<Uint64 Function(), int Function()>('WCharMinValue');
+
+int Function() wCharMaxValue = ffiTestFunctions
+    .lookupFunction<Uint64 Function(), int Function()>('WCharMaxValue');
diff --git a/tests/ffi_2/ffi_2.status b/tests/ffi_2/ffi_2.status
index 82ef75c..b119eb8 100644
--- a/tests/ffi_2/ffi_2.status
+++ b/tests/ffi_2/ffi_2.status
@@ -47,3 +47,9 @@
 
 [ $compiler == dart2analyzer || $compiler == fasta ]
 vmspecific_enable_ffi_test: SkipByDesign # This is a check for VM only.
+
+[ $compiler == dartkp || $arch == arm64 && $system == fuchsia ]
+abi_specific_int_incomplete_jit_test: SkipByDesign # Only intended to run in JIT mode.
+
+[ $compiler != dartkp || $arch == arm64 && $system == fuchsia ]
+abi_specific_int_incomplete_aot_test: SkipByDesign # Only intended to run in AOT mode.
diff --git a/tests/ffi_2/function_callbacks_structs_by_value_generated_test.dart b/tests/ffi_2/function_callbacks_structs_by_value_generated_test.dart
index d593bd1..f4100fb 100644
--- a/tests/ffi_2/function_callbacks_structs_by_value_generated_test.dart
+++ b/tests/ffi_2/function_callbacks_structs_by_value_generated_test.dart
@@ -18,6 +18,9 @@
 import "package:expect/expect.dart";
 import "package:ffi/ffi.dart";
 
+// Reuse the AbiSpecificInts.
+import 'abi_specific_ints.dart';
+
 import 'callback_tests_utils.dart';
 
 import 'dylib_utils.dart';
@@ -368,6 +371,12 @@
           passUint8Struct1ByteBool, false),
       passUint8Struct1ByteBoolAfterCallback),
   CallbackTest.withCheck(
+      "PassWCharStructInlineArrayIntUintPtrx2LongUnsigned",
+      Pointer.fromFunction<
+              PassWCharStructInlineArrayIntUintPtrx2LongUnsignedType>(
+          passWCharStructInlineArrayIntUintPtrx2LongUnsigned, 0),
+      passWCharStructInlineArrayIntUintPtrx2LongUnsignedAfterCallback),
+  CallbackTest.withCheck(
       "ReturnStruct1ByteInt",
       Pointer.fromFunction<ReturnStruct1ByteIntType>(returnStruct1ByteInt),
       returnStruct1ByteIntAfterCallback),
@@ -8153,6 +8162,88 @@
   Expect.equals(1 % 2 != 0, result);
 }
 
+typedef PassWCharStructInlineArrayIntUintPtrx2LongUnsignedType = WChar Function(
+    WChar, StructInlineArrayInt, UintPtr, UintPtr, Long, UnsignedLong);
+
+// Global variables to be able to test inputs after callback returned.
+int passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a0 = 0;
+StructInlineArrayInt passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1 =
+    Pointer<StructInlineArrayInt>.fromAddress(0).ref;
+int passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a2 = 0;
+int passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a3 = 0;
+int passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a4 = 0;
+int passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a5 = 0;
+
+// Result variable also global, so we can delete it after the callback.
+int passWCharStructInlineArrayIntUintPtrx2LongUnsignedResult = 0;
+
+int passWCharStructInlineArrayIntUintPtrx2LongUnsignedCalculateResult() {
+  int result = 0;
+
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a0;
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[0];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[1];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[2];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[3];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[4];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[5];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[6];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[7];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[8];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1.a0[9];
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a2;
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a3;
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a4;
+  result += passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a5;
+
+  passWCharStructInlineArrayIntUintPtrx2LongUnsignedResult = result;
+
+  return result;
+}
+
+/// Returning a wchar.
+int passWCharStructInlineArrayIntUintPtrx2LongUnsigned(
+    int a0, StructInlineArrayInt a1, int a2, int a3, int a4, int a5) {
+  print(
+      "passWCharStructInlineArrayIntUintPtrx2LongUnsigned(${a0}, ${a1}, ${a2}, ${a3}, ${a4}, ${a5})");
+
+  // In legacy mode, possibly return null.
+  if (a0 == 84) {
+    print("returning null!");
+    return null;
+  }
+
+  // In both nnbd and legacy mode, possibly throw.
+  if (a0 == 42 || a0 == 84) {
+    print("throwing!");
+    throw Exception(
+        "PassWCharStructInlineArrayIntUintPtrx2LongUnsigned throwing on purpose!");
+  }
+
+  passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a0 = a0;
+  passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a1 = a1;
+  passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a2 = a2;
+  passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a3 = a3;
+  passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a4 = a4;
+  passWCharStructInlineArrayIntUintPtrx2LongUnsigned_a5 = a5;
+
+  final result =
+      passWCharStructInlineArrayIntUintPtrx2LongUnsignedCalculateResult();
+
+  print("result = $result");
+
+  return result;
+}
+
+void passWCharStructInlineArrayIntUintPtrx2LongUnsignedAfterCallback() {
+  final result =
+      passWCharStructInlineArrayIntUintPtrx2LongUnsignedCalculateResult();
+
+  print("after callback result = $result");
+
+  Expect.equals(120, result);
+}
+
 typedef ReturnStruct1ByteIntType = Struct1ByteInt Function(Int8);
 
 // Global variables to be able to test inputs after callback returned.
diff --git a/tests/ffi_2/function_structs_by_value_generated_compounds.dart b/tests/ffi_2/function_structs_by_value_generated_compounds.dart
index 8b7931f..6908177 100644
--- a/tests/ffi_2/function_structs_by_value_generated_compounds.dart
+++ b/tests/ffi_2/function_structs_by_value_generated_compounds.dart
@@ -9,6 +9,9 @@
 
 import 'dart:ffi';
 
+// Reuse the AbiSpecificInts.
+import 'abi_specific_ints.dart';
+
 class Struct1ByteBool extends Struct {
   @Bool()
   bool a0;
@@ -1259,3 +1262,10 @@
 
   String toString() => "(${a0}, ${a1}, ${a2})";
 }
+
+class StructInlineArrayInt extends Struct {
+  @Array(10)
+  Array<WChar> a0;
+
+  String toString() => "(${[for (var i0 = 0; i0 < 10; i0 += 1) a0[i0]]})";
+}
diff --git a/tests/ffi_2/function_structs_by_value_generated_leaf_test.dart b/tests/ffi_2/function_structs_by_value_generated_leaf_test.dart
index 3a75d81..7c64296 100644
--- a/tests/ffi_2/function_structs_by_value_generated_leaf_test.dart
+++ b/tests/ffi_2/function_structs_by_value_generated_leaf_test.dart
@@ -18,6 +18,9 @@
 import "package:expect/expect.dart";
 import "package:ffi/ffi.dart";
 
+// Reuse the AbiSpecificInts.
+import 'abi_specific_ints.dart';
+
 import 'dylib_utils.dart';
 
 // Reuse the compound classes.
@@ -91,6 +94,7 @@
     testPassUint8Boolx9Struct10BytesHomogeneousBoolBoolLeaf();
     testPassUint8Boolx9Struct10BytesInlineArrayBoolBoolLeaf();
     testPassUint8Struct1ByteBoolLeaf();
+    testPassWCharStructInlineArrayIntUintPtrx2LongUnsignedLeaf();
     testReturnStruct1ByteIntLeaf();
     testReturnStruct3BytesHomogeneousUint8Leaf();
     testReturnStruct3BytesInt2ByteAlignedLeaf();
@@ -5463,6 +5467,50 @@
   calloc.free(a1Pointer);
 }
 
+final passWCharStructInlineArrayIntUintPtrx2LongUnsignedLeaf = ffiTestFunctions
+    .lookupFunction<
+            WChar Function(WChar, StructInlineArrayInt, UintPtr, UintPtr, Long,
+                UnsignedLong),
+            int Function(int, StructInlineArrayInt, int, int, int, int)>(
+        "PassWCharStructInlineArrayIntUintPtrx2LongUnsigned",
+        isLeaf: true);
+
+/// Returning a wchar.
+void testPassWCharStructInlineArrayIntUintPtrx2LongUnsignedLeaf() {
+  int a0;
+  final a1Pointer = calloc<StructInlineArrayInt>();
+  final StructInlineArrayInt a1 = a1Pointer.ref;
+  int a2;
+  int a3;
+  int a4;
+  int a5;
+
+  a0 = 1;
+  a1.a0[0] = 2;
+  a1.a0[1] = 3;
+  a1.a0[2] = 4;
+  a1.a0[3] = 5;
+  a1.a0[4] = 6;
+  a1.a0[5] = 7;
+  a1.a0[6] = 8;
+  a1.a0[7] = 9;
+  a1.a0[8] = 10;
+  a1.a0[9] = 11;
+  a2 = 12;
+  a3 = 13;
+  a4 = 14;
+  a5 = 15;
+
+  final result = passWCharStructInlineArrayIntUintPtrx2LongUnsignedLeaf(
+      a0, a1, a2, a3, a4, a5);
+
+  print("result = $result");
+
+  Expect.equals(120, result);
+
+  calloc.free(a1Pointer);
+}
+
 final returnStruct1ByteIntLeaf = ffiTestFunctions.lookupFunction<
     Struct1ByteInt Function(Int8),
     Struct1ByteInt Function(int)>("ReturnStruct1ByteInt", isLeaf: true);
diff --git a/tests/ffi_2/function_structs_by_value_generated_test.dart b/tests/ffi_2/function_structs_by_value_generated_test.dart
index f817df0..ef24ad2 100644
--- a/tests/ffi_2/function_structs_by_value_generated_test.dart
+++ b/tests/ffi_2/function_structs_by_value_generated_test.dart
@@ -18,6 +18,9 @@
 import "package:expect/expect.dart";
 import "package:ffi/ffi.dart";
 
+// Reuse the AbiSpecificInts.
+import 'abi_specific_ints.dart';
+
 import 'dylib_utils.dart';
 
 // Reuse the compound classes.
@@ -91,6 +94,7 @@
     testPassUint8Boolx9Struct10BytesHomogeneousBoolBool();
     testPassUint8Boolx9Struct10BytesInlineArrayBoolBool();
     testPassUint8Struct1ByteBool();
+    testPassWCharStructInlineArrayIntUintPtrx2LongUnsigned();
     testReturnStruct1ByteInt();
     testReturnStruct3BytesHomogeneousUint8();
     testReturnStruct3BytesInt2ByteAligned();
@@ -5387,6 +5391,49 @@
   calloc.free(a1Pointer);
 }
 
+final passWCharStructInlineArrayIntUintPtrx2LongUnsigned =
+    ffiTestFunctions.lookupFunction<
+        WChar Function(
+            WChar, StructInlineArrayInt, UintPtr, UintPtr, Long, UnsignedLong),
+        int Function(int, StructInlineArrayInt, int, int, int,
+            int)>("PassWCharStructInlineArrayIntUintPtrx2LongUnsigned");
+
+/// Returning a wchar.
+void testPassWCharStructInlineArrayIntUintPtrx2LongUnsigned() {
+  int a0;
+  final a1Pointer = calloc<StructInlineArrayInt>();
+  final StructInlineArrayInt a1 = a1Pointer.ref;
+  int a2;
+  int a3;
+  int a4;
+  int a5;
+
+  a0 = 1;
+  a1.a0[0] = 2;
+  a1.a0[1] = 3;
+  a1.a0[2] = 4;
+  a1.a0[3] = 5;
+  a1.a0[4] = 6;
+  a1.a0[5] = 7;
+  a1.a0[6] = 8;
+  a1.a0[7] = 9;
+  a1.a0[8] = 10;
+  a1.a0[9] = 11;
+  a2 = 12;
+  a3 = 13;
+  a4 = 14;
+  a5 = 15;
+
+  final result = passWCharStructInlineArrayIntUintPtrx2LongUnsigned(
+      a0, a1, a2, a3, a4, a5);
+
+  print("result = $result");
+
+  Expect.equals(120, result);
+
+  calloc.free(a1Pointer);
+}
+
 final returnStruct1ByteInt = ffiTestFunctions.lookupFunction<
     Struct1ByteInt Function(Int8),
     Struct1ByteInt Function(int)>("ReturnStruct1ByteInt");
diff --git a/tests/ffi_2/vmspecific_static_checks_test.dart b/tests/ffi_2/vmspecific_static_checks_test.dart
index 165b25c..ecb15cb 100644
--- a/tests/ffi_2/vmspecific_static_checks_test.dart
+++ b/tests/ffi_2/vmspecific_static_checks_test.dart
@@ -847,3 +847,35 @@
   @Array.multi([2, 2, 2, 2, 2, 2, -1]) //# 1802: compile-time error
   Array<Uint8> inlineArray; //# 1802: compile-time error
 }
+
+@AbiSpecificIntegerMapping({
+  Abi.androidArm: Uint32(),
+  Abi.androidArm64: IntPtr(), //# 1900: compile-time error
+  Abi.androidIA32: AbiSpecificInteger1(), //# 1901: compile-time error
+})
+@AbiSpecificIntegerMapping({}) //# 1902: compile-time error
+class AbiSpecificInteger1 extends AbiSpecificInteger {
+  const AbiSpecificInteger1();
+
+  int get a => 4; //# 1910: compile-time error
+
+  int b; //# 1911: compile-time error
+}
+
+class AbiSpecificInteger2
+    implements AbiSpecificInteger //# 1903: compile-time error
+{
+  const AbiSpecificInteger2();
+}
+
+class AbiSpecificInteger3
+    extends AbiSpecificInteger1 //# 1904: compile-time error
+{
+  const AbiSpecificInteger3();
+}
+
+class AbiSpecificInteger4
+    implements AbiSpecificInteger1 //# 1905: compile-time error
+{
+  const AbiSpecificInteger4();
+}
diff --git a/tests/lib/html/js_interop_constructor_name/error1_test.dart b/tests/lib/html/js_interop_constructor_name/error1_test.dart
index a12be51..d464c18 100644
--- a/tests/lib/html/js_interop_constructor_name/error1_test.dart
+++ b/tests/lib/html/js_interop_constructor_name/error1_test.dart
@@ -12,9 +12,14 @@
   setUpJS();
   test('dom-is-js', () {
     var e = confuse(new html.DivElement());
-    // Currently, HTML types are not [JavaScriptObject]s. We could change that
-    // by having HTML types extend JavaScriptObject, in which case we would
-    // change this expectation.
+    // Currently, HTML types are not `LegacyJavaScriptObject`s, so therefore
+    // they cannot be used with the usual `package:js` types.
     expect(e is HTMLDivElement, isFalse);
   });
+  test('dom-is-static-js', () {
+    var e = confuse(new html.DivElement());
+    // However, HTML types are `JavaScriptObject`s, so they can be used with
+    // static `package:js` types, using `@staticInterop`.
+    expect(e is StaticHTMLDivElement, isTrue);
+  });
 }
diff --git a/tests/lib/html/js_interop_constructor_name/error2_test.dart b/tests/lib/html/js_interop_constructor_name/error2_test.dart
index 365e418..e2ef8d3 100644
--- a/tests/lib/html/js_interop_constructor_name/error2_test.dart
+++ b/tests/lib/html/js_interop_constructor_name/error2_test.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'dart:html' as html;
-
 import 'package:expect/minitest.dart';
 
 import 'util.dart';
@@ -16,5 +14,6 @@
     // to Interceptor, but should be added to the class that implements all
     // the JS-interop methods.
     expect(e is HTMLDivElement, isFalse);
+    expect(e is StaticHTMLDivElement, isFalse);
   });
 }
diff --git a/tests/lib/html/js_interop_constructor_name/method_test.dart b/tests/lib/html/js_interop_constructor_name/method_test.dart
index 9781829..3d3099f 100644
--- a/tests/lib/html/js_interop_constructor_name/method_test.dart
+++ b/tests/lib/html/js_interop_constructor_name/method_test.dart
@@ -30,4 +30,14 @@
     var e = confuse(new html.DivElement());
     Expect.type<html.DivElement>(e.clone(false));
   });
+
+  test('js-call-static-js-method', () {
+    StaticHTMLDivElement e = confuse(makeDiv('hello'));
+    expect(e.bar(), equals('hello'));
+  });
+
+  test('dom-call-static-js-method', () {
+    StaticHTMLDivElement e = confuse(new html.DivElement());
+    Expect.type<html.DivElement>(e.cloneNode(false));
+  });
 }
diff --git a/tests/lib/html/js_interop_constructor_name/util.dart b/tests/lib/html/js_interop_constructor_name/util.dart
index 3ec4563..135518d 100644
--- a/tests/lib/html/js_interop_constructor_name/util.dart
+++ b/tests/lib/html/js_interop_constructor_name/util.dart
@@ -20,6 +20,15 @@
   external String bar();
 }
 
+@JS('Foo.HTMLDivElement')
+@staticInterop
+class StaticHTMLDivElement {}
+
+extension StaticHTMLDivElementExtension on StaticHTMLDivElement {
+  external String bar();
+  external StaticHTMLDivElement cloneNode(bool? deep);
+}
+
 @pragma('dart2js:noInline')
 @pragma('dart2js:assumeDynamic')
 confuse(x) => x;
diff --git a/tests/lib/isolate/scenarios/automatic_resolution_root/package_resolve_test.dart b/tests/lib/isolate/scenarios/automatic_resolution_root/package_resolve_test.dart
deleted file mode 100644
index eb3cbf7..0000000
--- a/tests/lib/isolate/scenarios/automatic_resolution_root/package_resolve_test.dart
+++ /dev/null
@@ -1,51 +0,0 @@
-// Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-import 'dart:io';
-import 'dart:isolate';
-
-final PACKAGE_URI = "package:foo/bar.dart";
-
-main([args, port]) async {
-  if (port != null) {
-    testPackageResolution(port);
-    return;
-  }
-  var p = new RawReceivePort();
-  Isolate.spawnUri(Platform.script, [], p.sendPort,
-      automaticPackageResolution: true);
-  p.handler = (msg) {
-    p.close();
-    if (msg is! List) {
-      print(msg.runtimeType);
-      throw "Failure return from spawned isolate:\n\n$msg";
-    }
-    if (msg[0] != null) {
-      throw "Bad package root in child isolate: ${msg[0]}.\n"
-          "Expected: null";
-    }
-    if (msg[1] != null) {
-      throw "Package path not matching: ${msg[1]}\n"
-          "Expected: null";
-    }
-    print("SUCCESS");
-  };
-  print("Spawning isolate's package root: ${await Isolate.packageRoot}");
-}
-
-testPackageResolution(port) async {
-  try {
-    var packageRootStr = Platform.packageRoot;
-    var packageConfigStr = Platform.packageConfig;
-    var packageRoot = await Isolate.packageRoot;
-    var resolvedPkg = await Isolate.resolvePackageUri(Uri.parse(PACKAGE_URI));
-    print("Spawned isolate's package root flag: $packageRootStr");
-    print("Spawned isolate's package config flag: $packageConfigStr");
-    print("Spawned isolate's loaded package root: $packageRoot");
-    print("Spawned isolate's resolved package path: $resolvedPkg");
-    port.send([packageRoot?.toString(), resolvedPkg?.toString()]);
-  } catch (e, s) {
-    port.send("$e\n$s\n");
-  }
-}
diff --git a/tests/lib/isolate/scenarios/automatic_resolution_spec/package_resolve_test.dart b/tests/lib/isolate/scenarios/automatic_resolution_spec/package_resolve_test.dart
index dee6d10..4b2eba6 100644
--- a/tests/lib/isolate/scenarios/automatic_resolution_spec/package_resolve_test.dart
+++ b/tests/lib/isolate/scenarios/automatic_resolution_spec/package_resolve_test.dart
@@ -32,16 +32,13 @@
     }
     print("SUCCESS");
   };
-  print("Spawning isolate's package root: ${await Isolate.packageRoot}");
 }
 
 testPackageResolution(port) async {
   try {
-    var packageRootStr = Platform.packageRoot;
     var packageConfigStr = Platform.packageConfig;
     var packageConfig = await Isolate.packageConfig;
     var resolvedPkg = await Isolate.resolvePackageUri(Uri.parse(PACKAGE_URI));
-    print("Spawned isolate's package root flag: $packageRootStr");
     print("Spawned isolate's package config flag: $packageConfigStr");
     print("Spawned isolate's loaded package config: $packageConfig");
     print("Spawned isolate's resolved package path: $resolvedPkg");
diff --git a/tests/lib/isolate/scenarios/bad_resolve_package/bad_resolve_package_test.dart b/tests/lib/isolate/scenarios/bad_resolve_package/bad_resolve_package_test.dart
index 5866729..1242b21 100644
--- a/tests/lib/isolate/scenarios/bad_resolve_package/bad_resolve_package_test.dart
+++ b/tests/lib/isolate/scenarios/bad_resolve_package/bad_resolve_package_test.dart
@@ -31,12 +31,10 @@
 
 testBadResolvePackage(port) async {
   try {
-    var packageRootStr = Platform.packageRoot;
     var packageConfigStr = Platform.packageConfig;
     var packageConfig = await Isolate.packageConfig;
     var badPackageUri = Uri.parse("package:asdf/qwerty.dart");
     var resolvedPkg = await Isolate.resolvePackageUri(badPackageUri);
-    print("Spawned isolate's package root flag: $packageRootStr");
     print("Spawned isolate's package config flag: $packageConfigStr");
     print("Spawned isolate's loaded package config: $packageConfig");
     print("Spawned isolate's resolved package path: $resolvedPkg");
diff --git a/tests/lib/isolate/scenarios/package_relative_root/package_relative_root_test.dart b/tests/lib/isolate/scenarios/package_relative_root/package_relative_root_test.dart
index 034881b..47f4d3d 100644
--- a/tests/lib/isolate/scenarios/package_relative_root/package_relative_root_test.dart
+++ b/tests/lib/isolate/scenarios/package_relative_root/package_relative_root_test.dart
@@ -7,8 +7,8 @@
 import 'dart:io';
 import 'dart:isolate';
 
-import "package:foo/foo.dart";
 import "package:bar/bar.dart";
+import "package:foo/foo.dart";
 
 var CONFIG_URI = "package:bar/spawned_packages/";
 
@@ -18,8 +18,7 @@
     return;
   }
   var p = new RawReceivePort();
-  Isolate.spawnUri(Platform.script, [], p.sendPort,
-      packageRoot: Uri.parse(CONFIG_URI));
+  Isolate.spawnUri(Platform.script, [], p.sendPort);
   p.handler = (msg) {
     p.close();
     if (msg is! List) {
@@ -45,11 +44,9 @@
 
 testCorrectBarPackage(port) async {
   try {
-    var packageRootStr = Platform.packageRoot;
     var packageConfigStr = Platform.packageConfig;
     var packageConfig = await Isolate.packageConfig;
     var resolvedPkg = await Isolate.resolvePackageUri(Uri.parse(CONFIG_URI));
-    print("Spawned isolate's package root flag: $packageRootStr");
     print("Spawned isolate's package config flag: $packageConfigStr");
     print("Spawned isolate's loaded package config: $packageConfig");
     print("Spawned isolate's resolved package path: $resolvedPkg");
diff --git a/tests/lib/isolate/scenarios/package_relative_spec/package_relative_spec_test.dart b/tests/lib/isolate/scenarios/package_relative_spec/package_relative_spec_test.dart
index 9e5b603..6118d26 100644
--- a/tests/lib/isolate/scenarios/package_relative_spec/package_relative_spec_test.dart
+++ b/tests/lib/isolate/scenarios/package_relative_spec/package_relative_spec_test.dart
@@ -45,11 +45,9 @@
 
 testCorrectBarPackage(port) async {
   try {
-    var packageRootStr = Platform.packageRoot;
     var packageConfigStr = Platform.packageConfig;
     var packageConfig = await Isolate.packageConfig;
     var resolvedPkg = await Isolate.resolvePackageUri(Uri.parse(CONFIG_URI));
-    print("Spawned isolate's package root flag: $packageRootStr");
     print("Spawned isolate's package config flag: $packageConfigStr");
     print("Spawned isolate's loaded package config: $packageConfig");
     print("Spawned isolate's resolved package path: $resolvedPkg");
diff --git a/tests/lib/lib.status b/tests/lib/lib.status
index ccc6171..46bdedf 100644
--- a/tests/lib/lib.status
+++ b/tests/lib/lib.status
@@ -11,6 +11,9 @@
 developer/timeline_test: Skip # Not supported
 isolate/issue_24243_parent_isolate_test: Skip # Requires checked mode
 
+[ $runtime == d8 ]
+js/js_util/javascriptobject_extensions_test.dart: SkipByDesign # Uses dart:html.
+
 [ $runtime == dart_precompiled ]
 isolate/package_config_getter_test: SkipByDesign # AOT mode doesn't preserve package structure.
 
diff --git a/tests/lib_2/html/js_interop_constructor_name/error1_test.dart b/tests/lib_2/html/js_interop_constructor_name/error1_test.dart
index f28cc09..19f516c 100644
--- a/tests/lib_2/html/js_interop_constructor_name/error1_test.dart
+++ b/tests/lib_2/html/js_interop_constructor_name/error1_test.dart
@@ -14,9 +14,14 @@
   setUpJS();
   test('dom-is-js', () {
     var e = confuse(new html.DivElement());
-    // Currently, HTML types are not [JavaScriptObject]s. We could change that
-    // by having HTML types extend JavaScriptObject, in which case we would
-    // change this expectation.
+    // Currently, HTML types are not `LegacyJavaScriptObject`s, so therefore
+    // they cannot be used with the usual `package:js` types.
     expect(e is HTMLDivElement, isFalse);
   });
+  test('dom-is-static-js', () {
+    var e = confuse(new html.DivElement());
+    // However, HTML types are `JavaScriptObject`s, so they can be used with
+    // static `package:js` types, using `@staticInterop`.
+    expect(e is StaticHTMLDivElement, isTrue);
+  });
 }
diff --git a/tests/lib_2/html/js_interop_constructor_name/error2_test.dart b/tests/lib_2/html/js_interop_constructor_name/error2_test.dart
index 078a870..85b5117 100644
--- a/tests/lib_2/html/js_interop_constructor_name/error2_test.dart
+++ b/tests/lib_2/html/js_interop_constructor_name/error2_test.dart
@@ -4,8 +4,6 @@
 
 // @dart = 2.9
 
-import 'dart:html' as html;
-
 import 'package:expect/minitest.dart';
 
 import 'util.dart';
@@ -18,5 +16,6 @@
     // to Interceptor, but should be added to the class that implements all
     // the JS-interop methods.
     expect(e is HTMLDivElement, isFalse);
+    expect(e is StaticHTMLDivElement, isFalse);
   });
 }
diff --git a/tests/lib_2/html/js_interop_constructor_name/method_test.dart b/tests/lib_2/html/js_interop_constructor_name/method_test.dart
index a7fd842..251bf8d 100644
--- a/tests/lib_2/html/js_interop_constructor_name/method_test.dart
+++ b/tests/lib_2/html/js_interop_constructor_name/method_test.dart
@@ -32,4 +32,14 @@
     var e = confuse(new html.DivElement());
     Expect.type<html.DivElement>(e.clone(false));
   });
+
+  test('js-call-static-js-method', () {
+    StaticHTMLDivElement e = confuse(makeDiv('hello'));
+    expect(e.bar(), equals('hello'));
+  });
+
+  test('dom-call-static-js-method', () {
+    StaticHTMLDivElement e = confuse(new html.DivElement());
+    Expect.type<html.DivElement>(e.cloneNode(false));
+  });
 }
diff --git a/tests/lib_2/html/js_interop_constructor_name/util.dart b/tests/lib_2/html/js_interop_constructor_name/util.dart
index c98f612..bdb5602 100644
--- a/tests/lib_2/html/js_interop_constructor_name/util.dart
+++ b/tests/lib_2/html/js_interop_constructor_name/util.dart
@@ -22,6 +22,15 @@
   external String bar();
 }
 
+@JS('Foo.HTMLDivElement')
+@staticInterop
+class StaticHTMLDivElement {}
+
+extension StaticHTMLDivElementExtension on StaticHTMLDivElement {
+  external String bar();
+  external StaticHTMLDivElement cloneNode(bool deep);
+}
+
 @pragma('dart2js:noInline')
 @pragma('dart2js:assumeDynamic')
 confuse(x) => x;
diff --git a/tests/lib_2/isolate/scenarios/automatic_resolution_root/package_resolve_test.dart b/tests/lib_2/isolate/scenarios/automatic_resolution_root/package_resolve_test.dart
deleted file mode 100644
index 53ae200..0000000
--- a/tests/lib_2/isolate/scenarios/automatic_resolution_root/package_resolve_test.dart
+++ /dev/null
@@ -1,53 +0,0 @@
-// Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-// @dart = 2.9
-
-import 'dart:io';
-import 'dart:isolate';
-
-final PACKAGE_URI = "package:foo/bar.dart";
-
-main([args, port]) async {
-  if (port != null) {
-    testPackageResolution(port);
-    return;
-  }
-  var p = new RawReceivePort();
-  Isolate.spawnUri(Platform.script, [], p.sendPort,
-      automaticPackageResolution: true);
-  p.handler = (msg) {
-    p.close();
-    if (msg is! List) {
-      print(msg.runtimeType);
-      throw "Failure return from spawned isolate:\n\n$msg";
-    }
-    if (msg[0] != null) {
-      throw "Bad package root in child isolate: ${msg[0]}.\n"
-          "Expected: null";
-    }
-    if (msg[1] != null) {
-      throw "Package path not matching: ${msg[1]}\n"
-          "Expected: null";
-    }
-    print("SUCCESS");
-  };
-  print("Spawning isolate's package root: ${await Isolate.packageRoot}");
-}
-
-testPackageResolution(port) async {
-  try {
-    var packageRootStr = Platform.packageRoot;
-    var packageConfigStr = Platform.packageConfig;
-    var packageRoot = await Isolate.packageRoot;
-    var resolvedPkg = await Isolate.resolvePackageUri(Uri.parse(PACKAGE_URI));
-    print("Spawned isolate's package root flag: $packageRootStr");
-    print("Spawned isolate's package config flag: $packageConfigStr");
-    print("Spawned isolate's loaded package root: $packageRoot");
-    print("Spawned isolate's resolved package path: $resolvedPkg");
-    port.send([packageRoot?.toString(), resolvedPkg?.toString()]);
-  } catch (e, s) {
-    port.send("$e\n$s\n");
-  }
-}
diff --git a/tests/lib_2/isolate/scenarios/automatic_resolution_spec/package_resolve_test.dart b/tests/lib_2/isolate/scenarios/automatic_resolution_spec/package_resolve_test.dart
index 4e3cbbd..ccd9088 100644
--- a/tests/lib_2/isolate/scenarios/automatic_resolution_spec/package_resolve_test.dart
+++ b/tests/lib_2/isolate/scenarios/automatic_resolution_spec/package_resolve_test.dart
@@ -34,16 +34,13 @@
     }
     print("SUCCESS");
   };
-  print("Spawning isolate's package root: ${await Isolate.packageRoot}");
 }
 
 testPackageResolution(port) async {
   try {
-    var packageRootStr = Platform.packageRoot;
     var packageConfigStr = Platform.packageConfig;
     var packageConfig = await Isolate.packageConfig;
     var resolvedPkg = await Isolate.resolvePackageUri(Uri.parse(PACKAGE_URI));
-    print("Spawned isolate's package root flag: $packageRootStr");
     print("Spawned isolate's package config flag: $packageConfigStr");
     print("Spawned isolate's loaded package config: $packageConfig");
     print("Spawned isolate's resolved package path: $resolvedPkg");
diff --git a/tests/lib_2/isolate/scenarios/bad_resolve_package/bad_resolve_package_test.dart b/tests/lib_2/isolate/scenarios/bad_resolve_package/bad_resolve_package_test.dart
index a17f089..ccc4856 100644
--- a/tests/lib_2/isolate/scenarios/bad_resolve_package/bad_resolve_package_test.dart
+++ b/tests/lib_2/isolate/scenarios/bad_resolve_package/bad_resolve_package_test.dart
@@ -33,12 +33,10 @@
 
 testBadResolvePackage(port) async {
   try {
-    var packageRootStr = Platform.packageRoot;
     var packageConfigStr = Platform.packageConfig;
     var packageConfig = await Isolate.packageConfig;
     var badPackageUri = Uri.parse("package:asdf/qwerty.dart");
     var resolvedPkg = await Isolate.resolvePackageUri(badPackageUri);
-    print("Spawned isolate's package root flag: $packageRootStr");
     print("Spawned isolate's package config flag: $packageConfigStr");
     print("Spawned isolate's loaded package config: $packageConfig");
     print("Spawned isolate's resolved package path: $resolvedPkg");
diff --git a/tests/lib_2/isolate/scenarios/package_relative_root/package_relative_root_test.dart b/tests/lib_2/isolate/scenarios/package_relative_root/package_relative_root_test.dart
index 49ee784..03f1e0b 100644
--- a/tests/lib_2/isolate/scenarios/package_relative_root/package_relative_root_test.dart
+++ b/tests/lib_2/isolate/scenarios/package_relative_root/package_relative_root_test.dart
@@ -9,8 +9,8 @@
 import 'dart:io';
 import 'dart:isolate';
 
-import "package:foo/foo.dart";
 import "package:bar/bar.dart";
+import "package:foo/foo.dart";
 
 var CONFIG_URI = "package:bar/spawned_packages/";
 
@@ -20,8 +20,7 @@
     return;
   }
   var p = new RawReceivePort();
-  Isolate.spawnUri(Platform.script, [], p.sendPort,
-      packageRoot: Uri.parse(CONFIG_URI));
+  Isolate.spawnUri(Platform.script, [], p.sendPort);
   p.handler = (msg) {
     p.close();
     if (msg is! List) {
@@ -47,11 +46,9 @@
 
 testCorrectBarPackage(port) async {
   try {
-    var packageRootStr = Platform.packageRoot;
     var packageConfigStr = Platform.packageConfig;
     var packageConfig = await Isolate.packageConfig;
     var resolvedPkg = await Isolate.resolvePackageUri(Uri.parse(CONFIG_URI));
-    print("Spawned isolate's package root flag: $packageRootStr");
     print("Spawned isolate's package config flag: $packageConfigStr");
     print("Spawned isolate's loaded package config: $packageConfig");
     print("Spawned isolate's resolved package path: $resolvedPkg");
diff --git a/tests/lib_2/isolate/scenarios/package_relative_spec/package_relative_spec_test.dart b/tests/lib_2/isolate/scenarios/package_relative_spec/package_relative_spec_test.dart
index a4c96d6..c8c7ea6 100644
--- a/tests/lib_2/isolate/scenarios/package_relative_spec/package_relative_spec_test.dart
+++ b/tests/lib_2/isolate/scenarios/package_relative_spec/package_relative_spec_test.dart
@@ -47,11 +47,9 @@
 
 testCorrectBarPackage(port) async {
   try {
-    var packageRootStr = Platform.packageRoot;
     var packageConfigStr = Platform.packageConfig;
     var packageConfig = await Isolate.packageConfig;
     var resolvedPkg = await Isolate.resolvePackageUri(Uri.parse(CONFIG_URI));
-    print("Spawned isolate's package root flag: $packageRootStr");
     print("Spawned isolate's package config flag: $packageConfigStr");
     print("Spawned isolate's loaded package config: $packageConfig");
     print("Spawned isolate's resolved package path: $resolvedPkg");
diff --git a/tests/lib_2/lib_2.status b/tests/lib_2/lib_2.status
index d79f2ba..bef1d69 100644
--- a/tests/lib_2/lib_2.status
+++ b/tests/lib_2/lib_2.status
@@ -11,6 +11,9 @@
 developer/timeline_test: Skip # Not supported
 isolate/issue_24243_parent_isolate_test: Skip # Requires checked mode
 
+[ $runtime == d8 ]
+js/js_util/javascriptobject_extensions_test.dart: SkipByDesign # Uses dart:html.
+
 [ $runtime == dart_precompiled ]
 isolate/package_config_getter_test: SkipByDesign # AOT mode doesn't preserve package structure.
 
diff --git a/tests/modular/cross_module_constant_with_mixin/a.dart b/tests/modular/cross_module_constant_with_mixin/a.dart
new file mode 100644
index 0000000..3e1b8b9
--- /dev/null
+++ b/tests/modular/cross_module_constant_with_mixin/a.dart
@@ -0,0 +1,25 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 't.dart';
+
+String _defaultStringy(String t) => t.toLowerCase();
+
+class A {
+  A({
+    double d = 3.14,
+    StringyFunction<String> s = _defaultStringy,
+  }) : this.factoryConstructor(d: d, s: s);
+
+  A.factoryConstructor({
+    double d = 3.14,
+    StringyFunction<String> s = _defaultStringy,
+  })  : d = d,
+        _s = s;
+
+  String doStringy(String i) => _s(i);
+
+  final double d;
+  final StringyFunction<String> _s;
+}
diff --git a/tests/modular/cross_module_constant_with_mixin/b.dart b/tests/modular/cross_module_constant_with_mixin/b.dart
new file mode 100644
index 0000000..03b89b8
--- /dev/null
+++ b/tests/modular/cross_module_constant_with_mixin/b.dart
@@ -0,0 +1,10 @@
+// Copyright (c) 2020, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'a.dart';
+import 'm.dart';
+
+class B extends A with M {
+  B({double d = 2.71}) : super(d: d);
+}
diff --git a/tests/modular/cross_module_constant_with_mixin/m.dart b/tests/modular/cross_module_constant_with_mixin/m.dart
new file mode 100644
index 0000000..e4f4935
--- /dev/null
+++ b/tests/modular/cross_module_constant_with_mixin/m.dart
@@ -0,0 +1,9 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'a.dart';
+
+mixin M on A {
+  m1() {}
+}
diff --git a/tests/modular/cross_module_constant_with_mixin/main.dart b/tests/modular/cross_module_constant_with_mixin/main.dart
new file mode 100644
index 0000000..8daaa4e
--- /dev/null
+++ b/tests/modular/cross_module_constant_with_mixin/main.dart
@@ -0,0 +1,13 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:expect/expect.dart';
+
+import 'b.dart';
+
+main() {
+  var bInst = B();
+  Expect.equals(2.71, bInst.d);
+  Expect.equals('default', bInst.doStringy('DEFAULT'));
+}
diff --git a/tests/modular/cross_module_constant_with_mixin/modules.yaml b/tests/modular/cross_module_constant_with_mixin/modules.yaml
new file mode 100644
index 0000000..54b3cdf
--- /dev/null
+++ b/tests/modular/cross_module_constant_with_mixin/modules.yaml
@@ -0,0 +1,9 @@
+# Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+# for details. All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE file.
+
+dependencies:
+  main: [a, b, m, expect]
+  b: [a, m]
+  m: a
+  a: t
diff --git a/tests/modular/cross_module_constant_with_mixin/t.dart b/tests/modular/cross_module_constant_with_mixin/t.dart
new file mode 100644
index 0000000..ab0db0e
--- /dev/null
+++ b/tests/modular/cross_module_constant_with_mixin/t.dart
@@ -0,0 +1,5 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+typedef StringyFunction<T> = String Function(T item);
diff --git a/tests/modular/static_interop_erasure/.packages b/tests/modular/static_interop_erasure/.packages
new file mode 100644
index 0000000..fce126f
--- /dev/null
+++ b/tests/modular/static_interop_erasure/.packages
@@ -0,0 +1 @@
+js:../../../pkg/js/lib
diff --git a/tests/modular/static_interop_erasure/main.dart b/tests/modular/static_interop_erasure/main.dart
new file mode 100644
index 0000000..80ccc3b
--- /dev/null
+++ b/tests/modular/static_interop_erasure/main.dart
@@ -0,0 +1,10 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'static_interop.dart';
+
+void main() {
+  setUp();
+  var staticJs = StaticJSClass.factory();
+}
diff --git a/tests/modular/static_interop_erasure/modules.yaml b/tests/modular/static_interop_erasure/modules.yaml
new file mode 100644
index 0000000..6d1a988
--- /dev/null
+++ b/tests/modular/static_interop_erasure/modules.yaml
@@ -0,0 +1,9 @@
+# Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+# for details. All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE file.
+#
+# Test that modular compilation still works with static interop classes that
+# contain factories.
+dependencies:
+  main: static_interop
+  static_interop: js
diff --git a/tests/modular/static_interop_erasure/static_interop.dart b/tests/modular/static_interop_erasure/static_interop.dart
new file mode 100644
index 0000000..a5c93c4
--- /dev/null
+++ b/tests/modular/static_interop_erasure/static_interop.dart
@@ -0,0 +1,24 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+@JS()
+library static_interop;
+
+import 'package:js/js.dart';
+
+@JS()
+external void eval(String code);
+
+@JS('JSClass')
+@staticInterop
+class StaticJSClass {
+  external StaticJSClass();
+  factory StaticJSClass.factory() {
+    return StaticJSClass();
+  }
+}
+
+void setUp() {
+  eval('''function JSClass() {}''');
+}
diff --git a/tests/standalone/io/io_override_test.dart b/tests/standalone/io/io_override_test.dart
index fb8c780..fdd49ba 100644
--- a/tests/standalone/io/io_override_test.dart
+++ b/tests/standalone/io/io_override_test.dart
@@ -161,12 +161,12 @@
 }
 
 Future<Socket> socketConnect(dynamic host, int port,
-    {dynamic sourceAddress, Duration? timeout}) {
+    {dynamic sourceAddress, int sourcePort = 0, Duration? timeout}) {
   throw "";
 }
 
 Future<ConnectionTask<Socket>> socketStartConnect(dynamic host, int port,
-    {dynamic sourceAddress}) {
+    {dynamic sourceAddress, int sourcePort = 0}) {
   throw "";
 }
 
diff --git a/tests/standalone/io/socket_local_port_test.dart b/tests/standalone/io/socket_local_port_test.dart
new file mode 100644
index 0000000..f7251ec
--- /dev/null
+++ b/tests/standalone/io/socket_local_port_test.dart
@@ -0,0 +1,162 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:async';
+import "dart:io";
+
+import "package:expect/expect.dart";
+
+Future testCustomPortIPv4() async {
+  String clientAddress = "127.0.0.1";
+  int customLocalPort = 50988;
+  String serverAddress = clientAddress;
+  int port = 50989;
+
+  testCustomPort(serverAddress, port, clientAddress, customLocalPort);
+}
+
+Future testCustomPortIPv6() async {
+  String clientAddress = "::1";
+  int customLocalPort = 50988;
+  String serverAddress = clientAddress;
+  int port = 50989;
+
+  testCustomPort(serverAddress, port, clientAddress, customLocalPort);
+}
+
+Future testCustomPortIPv4NoSourceAddress() async {
+  String expectedClientAddress = "127.0.0.1";
+  int customLocalPort = 50988;
+  String serverAddress = expectedClientAddress;
+  int port = 50989;
+
+  testCustomPort(serverAddress, port, expectedClientAddress, customLocalPort);
+}
+
+Future testCustomPortIPv6NoSourceAddress() async {
+  String expectedClientAddress = "::1";
+  int customLocalPort = 50988;
+  String serverAddress = expectedClientAddress;
+  int port = 50989;
+
+  testCustomPort(serverAddress, port, expectedClientAddress, customLocalPort);
+}
+
+Future testNoCustomPortIPv4() async {
+  String host = "127.0.0.1";
+  String clientAddress = host;
+  int serverPort = 39998;
+
+  await testNoCustomPortNoSourceAddress(host, serverPort, clientAddress);
+}
+
+Future testNoCustomPortIPv6() async {
+  String host = "::1";
+  String clientAddress = host;
+  int serverPort = 39998;
+
+  await testNoCustomPortNoSourceAddress(host, serverPort, clientAddress);
+}
+
+Future testNoCustomPortNoSourceAddressIPv4() async {
+  String host = "127.0.0.1";
+  String expectedAddress = host;
+  int serverPort = 39998;
+
+  await testNoCustomPortNoSourceAddress(host, serverPort, expectedAddress);
+}
+
+Future testNoCustomPortNoSourceAddressIPv6() async {
+  String host = "::1";
+  String expectedAddress = host;
+  int serverPort = 39998;
+
+  await testNoCustomPortNoSourceAddress(host, serverPort, expectedAddress);
+}
+
+// Core functionality
+void testCustomPort(
+    String host, int port, String sourceAddress, int sourcePort) async {
+  var server = await ServerSocket.bind(host, port);
+  server.listen((client) {
+    Expect.equals(server.port, port);
+    Expect.equals(client.remotePort, sourcePort);
+    Expect.equals(client.address.address, sourceAddress);
+    client.destroy();
+  });
+
+  Socket s = await Socket.connect(host, port,
+      sourceAddress: sourceAddress, sourcePort: sourcePort);
+  s.destroy();
+  server.close();
+}
+
+Future testCustomPortNoSourceAddress(
+    String host, int port, String expectedAddress, int sourcePort) async {
+  Completer completer = new Completer();
+  var server = await ServerSocket.bind(host, port);
+
+  server.listen((client) {
+    Expect.equals(server.port, port);
+    Expect.equals(client.remotePort, sourcePort);
+    Expect.equals(client.address.address, expectedAddress);
+    client.destroy();
+    completer.complete();
+  });
+
+  Socket s = await Socket.connect(host, port, sourcePort: sourcePort);
+  s.destroy();
+  server.close();
+
+  return completer.future;
+}
+
+Future testNoCustomPort(String host, int port, String sourceAddress) async {
+  Completer completer = new Completer();
+  var server = await ServerSocket.bind(host, port);
+  Socket.connect(host, port, sourceAddress: sourceAddress).then((clientSocket) {
+    server.listen((client) {
+      Expect.equals(server.port, port);
+      Expect.equals(client.remotePort, clientSocket.port);
+      Expect.equals(client.address.address, sourceAddress);
+
+      client.destroy();
+      completer.complete();
+    });
+
+    clientSocket.destroy();
+    server.close();
+  });
+
+  return completer.future;
+}
+
+Future testNoCustomPortNoSourceAddress(
+    String host, int port, String expectedAddress) async {
+  Completer completer = new Completer();
+  var server = await ServerSocket.bind(host, port);
+  Socket.connect(host, port).then((clientSocket) {
+    server.listen((client) {
+      Expect.equals(server.port, port);
+      Expect.equals(client.remotePort, clientSocket.port);
+      Expect.equals(client.address.address, expectedAddress);
+      clientSocket.destroy();
+      client.destroy();
+      server.close();
+      completer.complete();
+    });
+  });
+  return completer.future;
+}
+
+Future main() async {
+  await testCustomPortIPv4();
+  await testCustomPortIPv6();
+
+  await testNoCustomPortIPv4();
+  await testNoCustomPortIPv6();
+
+  await testNoCustomPortNoSourceAddressIPv4();
+  await testNoCustomPortNoSourceAddressIPv6();
+}
diff --git a/tests/standalone_2/io/io_override_test.dart b/tests/standalone_2/io/io_override_test.dart
index 5ac4160..e7d9a81 100644
--- a/tests/standalone_2/io/io_override_test.dart
+++ b/tests/standalone_2/io/io_override_test.dart
@@ -161,12 +161,12 @@
 }
 
 Future<Socket> socketConnect(host, int port,
-    {sourceAddress, Duration timeout}) {
+    {sourceAddress, int sourcePort, Duration timeout}) {
   return null;
 }
 
 Future<ConnectionTask<Socket>> socketStartConnect(host, int port,
-    {sourceAddress}) {
+    {sourceAddress, int sourcePort}) {
   return null;
 }
 
diff --git a/tests/standalone_2/io/socket_local_port_test.dart b/tests/standalone_2/io/socket_local_port_test.dart
new file mode 100644
index 0000000..f7251ec
--- /dev/null
+++ b/tests/standalone_2/io/socket_local_port_test.dart
@@ -0,0 +1,162 @@
+// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:async';
+import "dart:io";
+
+import "package:expect/expect.dart";
+
+Future testCustomPortIPv4() async {
+  String clientAddress = "127.0.0.1";
+  int customLocalPort = 50988;
+  String serverAddress = clientAddress;
+  int port = 50989;
+
+  testCustomPort(serverAddress, port, clientAddress, customLocalPort);
+}
+
+Future testCustomPortIPv6() async {
+  String clientAddress = "::1";
+  int customLocalPort = 50988;
+  String serverAddress = clientAddress;
+  int port = 50989;
+
+  testCustomPort(serverAddress, port, clientAddress, customLocalPort);
+}
+
+Future testCustomPortIPv4NoSourceAddress() async {
+  String expectedClientAddress = "127.0.0.1";
+  int customLocalPort = 50988;
+  String serverAddress = expectedClientAddress;
+  int port = 50989;
+
+  testCustomPort(serverAddress, port, expectedClientAddress, customLocalPort);
+}
+
+Future testCustomPortIPv6NoSourceAddress() async {
+  String expectedClientAddress = "::1";
+  int customLocalPort = 50988;
+  String serverAddress = expectedClientAddress;
+  int port = 50989;
+
+  testCustomPort(serverAddress, port, expectedClientAddress, customLocalPort);
+}
+
+Future testNoCustomPortIPv4() async {
+  String host = "127.0.0.1";
+  String clientAddress = host;
+  int serverPort = 39998;
+
+  await testNoCustomPortNoSourceAddress(host, serverPort, clientAddress);
+}
+
+Future testNoCustomPortIPv6() async {
+  String host = "::1";
+  String clientAddress = host;
+  int serverPort = 39998;
+
+  await testNoCustomPortNoSourceAddress(host, serverPort, clientAddress);
+}
+
+Future testNoCustomPortNoSourceAddressIPv4() async {
+  String host = "127.0.0.1";
+  String expectedAddress = host;
+  int serverPort = 39998;
+
+  await testNoCustomPortNoSourceAddress(host, serverPort, expectedAddress);
+}
+
+Future testNoCustomPortNoSourceAddressIPv6() async {
+  String host = "::1";
+  String expectedAddress = host;
+  int serverPort = 39998;
+
+  await testNoCustomPortNoSourceAddress(host, serverPort, expectedAddress);
+}
+
+// Core functionality
+void testCustomPort(
+    String host, int port, String sourceAddress, int sourcePort) async {
+  var server = await ServerSocket.bind(host, port);
+  server.listen((client) {
+    Expect.equals(server.port, port);
+    Expect.equals(client.remotePort, sourcePort);
+    Expect.equals(client.address.address, sourceAddress);
+    client.destroy();
+  });
+
+  Socket s = await Socket.connect(host, port,
+      sourceAddress: sourceAddress, sourcePort: sourcePort);
+  s.destroy();
+  server.close();
+}
+
+Future testCustomPortNoSourceAddress(
+    String host, int port, String expectedAddress, int sourcePort) async {
+  Completer completer = new Completer();
+  var server = await ServerSocket.bind(host, port);
+
+  server.listen((client) {
+    Expect.equals(server.port, port);
+    Expect.equals(client.remotePort, sourcePort);
+    Expect.equals(client.address.address, expectedAddress);
+    client.destroy();
+    completer.complete();
+  });
+
+  Socket s = await Socket.connect(host, port, sourcePort: sourcePort);
+  s.destroy();
+  server.close();
+
+  return completer.future;
+}
+
+Future testNoCustomPort(String host, int port, String sourceAddress) async {
+  Completer completer = new Completer();
+  var server = await ServerSocket.bind(host, port);
+  Socket.connect(host, port, sourceAddress: sourceAddress).then((clientSocket) {
+    server.listen((client) {
+      Expect.equals(server.port, port);
+      Expect.equals(client.remotePort, clientSocket.port);
+      Expect.equals(client.address.address, sourceAddress);
+
+      client.destroy();
+      completer.complete();
+    });
+
+    clientSocket.destroy();
+    server.close();
+  });
+
+  return completer.future;
+}
+
+Future testNoCustomPortNoSourceAddress(
+    String host, int port, String expectedAddress) async {
+  Completer completer = new Completer();
+  var server = await ServerSocket.bind(host, port);
+  Socket.connect(host, port).then((clientSocket) {
+    server.listen((client) {
+      Expect.equals(server.port, port);
+      Expect.equals(client.remotePort, clientSocket.port);
+      Expect.equals(client.address.address, expectedAddress);
+      clientSocket.destroy();
+      client.destroy();
+      server.close();
+      completer.complete();
+    });
+  });
+  return completer.future;
+}
+
+Future main() async {
+  await testCustomPortIPv4();
+  await testCustomPortIPv6();
+
+  await testNoCustomPortIPv4();
+  await testNoCustomPortIPv6();
+
+  await testNoCustomPortNoSourceAddressIPv4();
+  await testNoCustomPortNoSourceAddressIPv6();
+}
diff --git a/tests/web/internal/javascriptobject_extensions_test.dart b/tests/web/internal/javascriptobject_extensions_test.dart
index 4edd79d..90ad415 100644
--- a/tests/web/internal/javascriptobject_extensions_test.dart
+++ b/tests/web/internal/javascriptobject_extensions_test.dart
@@ -12,9 +12,14 @@
 import 'package:expect/expect.dart' show hasUnsoundNullSafety;
 import 'package:expect/minitest.dart';
 
-import 'dart:typed_data';
+import 'dart:html' show Window;
+import 'dart:typed_data' show ByteBuffer;
 import 'dart:_interceptors'
-    show JavaScriptObject, UnknownJavaScriptObject, JSObject;
+    show
+        LegacyJavaScriptObject,
+        JavaScriptObject,
+        UnknownJavaScriptObject,
+        JSObject;
 
 @JS()
 external void eval(String code);
@@ -46,6 +51,11 @@
 @JS('arrayBuffer')
 external dynamic get arrayBufferDynamic;
 
+external Window get window;
+
+@JS('window')
+external dynamic get windowDynamic;
+
 // Extension on JavaScriptObject. In the future, when extension types are
 // introduced, this will be explicitly disallowed.
 extension JavaScriptObjectExtension on JavaScriptObject {
@@ -112,19 +122,33 @@
   expect(javaScriptObject is DartClass, false);
   runtimeIsAndAs<DartClass>(javaScriptObject, false);
 
-  // Native objects cannot be casted to or from JavaScriptObject.
+  // Web Native classes are subclasses of JavaScriptObject, but not
+  // LegacyJavaScriptObject.
+  expect(window is JavaScriptObject, true);
+  runtimeIsAndAs<JavaScriptObject>(window, true);
+  runtimeIsAndAs<JavaScriptObject>(windowDynamic, true);
+  javaScriptObject = jsObj as JavaScriptObject;
+  expect(javaScriptObject is Window, false);
+  runtimeIsAndAs<Window>(javaScriptObject, false);
+
+  expect(window is LegacyJavaScriptObject, false);
+  runtimeIsAndAs<LegacyJavaScriptObject>(window, false);
+  runtimeIsAndAs<LegacyJavaScriptObject>(windowDynamic, false);
+  var legacyJavaScriptObject = jsObj as LegacyJavaScriptObject;
+  expect(legacyJavaScriptObject is Window, false);
+  runtimeIsAndAs<Window>(legacyJavaScriptObject, false);
+
+  // Non-web Native classes like those in `dart:typed_data` are not subclasses
+  // of JavaScriptObject.
   expect(arrayBuffer is JavaScriptObject, false);
   runtimeIsAndAs<JavaScriptObject>(arrayBuffer, false);
+  runtimeIsAndAs<JavaScriptObject>(arrayBufferDynamic, false);
   expect(javaScriptObject is ByteBuffer, false);
   runtimeIsAndAs<ByteBuffer>(javaScriptObject, false);
 
-  // Dynamic native objects are intercepted and cannot be casted to
-  // JavaScriptObject.
-  runtimeIsAndAs<JavaScriptObject>(arrayBufferDynamic, false);
-
   // Make sure `Object` methods work with JavaScriptObject like they do with JS
   // interop objects.
-  expect(anonymousObj == javaScriptObject, true);
+  expect(javaScriptObject == jsObj, true);
   expect(javaScriptObject.hashCode, isNotNull);
   expect(javaScriptObject.toString, isNotNull);
   expect(javaScriptObject.noSuchMethod, isNotNull);
diff --git a/tests/web/internal/rti/js_interop_subtype_test.dart b/tests/web/internal/rti/js_interop_subtype_test.dart
index 66010da..ffcb31c 100644
--- a/tests/web/internal/rti/js_interop_subtype_test.dart
+++ b/tests/web/internal/rti/js_interop_subtype_test.dart
@@ -17,6 +17,6 @@
   eval(r'''
       function JSClass() {}
       ''');
-  Expect.type<JavaScriptObject>(JSClass());
-  Expect.type<List<JavaScriptObject>>(<JSClass>[]);
+  Expect.type<LegacyJavaScriptObject>(JSClass());
+  Expect.type<List<LegacyJavaScriptObject>>(<JSClass>[]);
 }
diff --git a/tests/web/native/error_safeToString_test.dart b/tests/web/native/error_safeToString_test.dart
index ecb3544..333b9c7 100644
--- a/tests/web/native/error_safeToString_test.dart
+++ b/tests/web/native/error_safeToString_test.dart
@@ -7,7 +7,7 @@
 import 'dart:_interceptors'
     show
         Interceptor,
-        JavaScriptObject,
+        LegacyJavaScriptObject,
         PlainJavaScriptObject,
         UnknownJavaScriptObject;
 
diff --git a/tests/web/native/jsobject_test.dart b/tests/web/native/jsobject_test.dart
index 0b769d0..5604920 100644
--- a/tests/web/native/jsobject_test.dart
+++ b/tests/web/native/jsobject_test.dart
@@ -8,7 +8,7 @@
     show
         JSObject, // The interface, which may be re-exported by a
         // js-interop library.
-        JavaScriptObject, //   The interceptor abstract class.
+        LegacyJavaScriptObject, //   The interceptor abstract class.
         PlainJavaScriptObject, //     The interceptor concrete class.
         UnknownJavaScriptObject, //     The interceptor concrete class.
         Interceptor;
@@ -47,21 +47,21 @@
 static_test() {
   var x = makeA();
   Expect.isTrue(x is JSObject);
-  Expect.isTrue(x is JavaScriptObject);
+  Expect.isTrue(x is LegacyJavaScriptObject);
   Expect.isTrue(x is PlainJavaScriptObject);
   Expect.isTrue(x is! UnknownJavaScriptObject);
   Expect.equals(JSObject, x.runtimeType);
 
   x = makeB();
   Expect.isTrue(x is JSObject);
-  Expect.isTrue(x is JavaScriptObject);
+  Expect.isTrue(x is LegacyJavaScriptObject);
   Expect.isTrue(x is! PlainJavaScriptObject);
   Expect.isTrue(x is UnknownJavaScriptObject);
   Expect.equals(JSObject, x.runtimeType);
 
   x = makeQ();
   Expect.isFalse(x is JSObject);
-  Expect.isFalse(x is JavaScriptObject);
+  Expect.isFalse(x is LegacyJavaScriptObject);
   Expect.isFalse(x is PlainJavaScriptObject);
   Expect.isFalse(x is UnknownJavaScriptObject);
   Expect.isFalse(x.runtimeType == JSObject);
@@ -71,27 +71,27 @@
 dynamic_test() {
   var x = makeA();
   var isJSObject = new Is<JSObject>().check;
-  var isJavaScriptObject = new Is<JavaScriptObject>().check;
+  var isLegacyJavaScriptObject = new Is<LegacyJavaScriptObject>().check;
   var isPlainJavaScriptObject = new Is<PlainJavaScriptObject>().check;
   var isUnknownJavaScriptObject = new Is<UnknownJavaScriptObject>().check;
   var isQ = new Is<Q>().check;
 
   Expect.isTrue(isJSObject(x));
-  Expect.isTrue(isJavaScriptObject(x));
+  Expect.isTrue(isLegacyJavaScriptObject(x));
   Expect.isTrue(isPlainJavaScriptObject(x));
   Expect.isTrue(!isUnknownJavaScriptObject(x));
   Expect.equals(JSObject, x.runtimeType);
 
   x = makeB();
   Expect.isTrue(isJSObject(x));
-  Expect.isTrue(isJavaScriptObject(x));
+  Expect.isTrue(isLegacyJavaScriptObject(x));
   Expect.isTrue(!isPlainJavaScriptObject(x));
   Expect.isTrue(isUnknownJavaScriptObject(x));
   Expect.equals(JSObject, x.runtimeType);
 
   x = makeQ();
   Expect.isFalse(isJSObject(x));
-  Expect.isFalse(isJavaScriptObject(x));
+  Expect.isFalse(isLegacyJavaScriptObject(x));
   Expect.isFalse(isPlainJavaScriptObject(x));
   Expect.isFalse(isUnknownJavaScriptObject(x));
   Expect.isTrue(isQ(x));
diff --git a/tests/web/native/static_interop_erasure/factory_stub_test.dart b/tests/web/native/static_interop_erasure/factory_stub_test.dart
new file mode 100644
index 0000000..71fe516
--- /dev/null
+++ b/tests/web/native/static_interop_erasure/factory_stub_test.dart
@@ -0,0 +1,73 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// Test that factory methods with bodies are stubbed correctly in static interop
+// type erasure.
+
+@JS()
+library factory_stub_test;
+
+import 'dart:_interceptors' show JavaScriptObject;
+
+import 'package:js/js.dart';
+
+import '../native_testing.dart';
+import '../native_testing.dart' as native_testing;
+
+NativeClass makeNativeClass() native;
+
+@Native('NativeClass')
+class NativeClass extends JavaScriptObject {
+  factory NativeClass() => makeNativeClass();
+}
+
+@JS('NativeClass')
+@staticInterop
+class StaticNativeClass {
+  external StaticNativeClass();
+  factory StaticNativeClass.redirectingFactory() = StaticNativeClass;
+  factory StaticNativeClass.simpleFactory() => StaticNativeClass();
+  factory StaticNativeClass.factoryWithParam(
+          StaticNativeClass staticNativeClass) =>
+      staticNativeClass;
+  // This and `StaticNativeClassCopy.nestedFactory` exist to ensure that we
+  // cover the case where invocations on factories are visible before their
+  // declarations in the AST. This will test whether we correctly create the
+  // stub even if we haven't visited the declaration yet.
+  factory StaticNativeClass.nestedFactory() {
+    StaticNativeClassCopy.nestedFactory();
+    return StaticNativeClass();
+  }
+}
+
+@JS('NativeClass')
+@staticInterop
+class StaticNativeClassCopy {
+  external StaticNativeClassCopy();
+  factory StaticNativeClassCopy.nestedFactory() {
+    StaticNativeClass.simpleFactory();
+    return StaticNativeClassCopy();
+  }
+}
+
+void main() {
+  nativeTesting();
+  native_testing.JS('', r'''
+    (function(){
+      function NativeClass() {}
+      self.NativeClass = NativeClass;
+      self.makeNativeClass = function(){return new NativeClass()};
+      self.nativeConstructor(NativeClass);
+    })()
+  ''');
+  applyTestExtensions(['NativeClass']);
+
+  // Make the Native class live.
+  NativeClass();
+  // Invoke factories and ensure they're typed correctly through assignment.
+  StaticNativeClass staticNativeClass = StaticNativeClass.redirectingFactory();
+  staticNativeClass = StaticNativeClass.simpleFactory();
+  staticNativeClass = StaticNativeClass.factoryWithParam(staticNativeClass);
+  staticNativeClass = StaticNativeClass.nestedFactory();
+}
diff --git a/tests/web/native/static_interop_erasure/type_test.dart b/tests/web/native/static_interop_erasure/type_test.dart
new file mode 100644
index 0000000..c3081b8
--- /dev/null
+++ b/tests/web/native/static_interop_erasure/type_test.dart
@@ -0,0 +1,244 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// Test that the type and subtyping relationships between static interop,
+// non-static interop, and Native classes are well-formed.
+
+@JS()
+library type_test;
+
+import 'dart:_interceptors' show JavaScriptObject;
+
+import 'package:expect/expect.dart' show hasUnsoundNullSafety;
+import 'package:expect/minitest.dart';
+import 'package:js/js.dart';
+
+import '../native_testing.dart';
+import '../native_testing.dart' as native_testing;
+
+NativeClass makeNativeClass() native;
+
+@Native('NativeClass')
+class NativeClass extends JavaScriptObject {
+  factory NativeClass() => makeNativeClass();
+}
+
+@JS('NativeClass')
+@staticInterop
+class StaticNativeClass {
+  external StaticNativeClass();
+}
+
+@JS()
+class JSClass {
+  external JSClass();
+}
+
+@JS('JSClass')
+@staticInterop
+class StaticJSClass {
+  external StaticJSClass();
+}
+
+@JS()
+@anonymous
+class AnonymousClass {
+  external factory();
+}
+
+@JS()
+@staticInterop
+class GenericStaticJSClass<T> {}
+
+NativeClass returnNativeClass() => throw '';
+
+StaticNativeClass returnStaticNativeClass() => throw '';
+
+JSClass returnJSClass() => throw '';
+
+StaticJSClass returnStaticJSClass() => throw '';
+
+AnonymousClass returnAnonymousClass() => throw '';
+
+GenericStaticJSClass<int> returnGenericStaticJSClassInt() => throw '';
+
+StaticJSClass? returnNullableStaticJSClass() => throw '';
+
+void main() {
+  nativeTesting();
+  native_testing.JS('', r'''
+    (function(){
+      function NativeClass() {}
+      self.NativeClass = NativeClass;
+      self.makeNativeClass = function(){return new NativeClass()};
+      self.nativeConstructor(NativeClass);
+      function JSClass() {}
+      self.JSClass = JSClass;
+    })()
+  ''');
+  applyTestExtensions(['NativeClass']);
+
+  var nativeClass = NativeClass();
+  var staticNativeClass = StaticNativeClass();
+  var jsClass = JSClass();
+  var staticJsClass = StaticJSClass();
+  var anonymousClass = AnonymousClass();
+
+  // Test that nullability of the type is respected in erasure.
+  expect(null is StaticJSClass?, true);
+  expect(confuse(null) is StaticJSClass?, true);
+  expect(() => null as StaticJSClass?, returnsNormally);
+  expect(null is StaticJSClass, false);
+  expect(confuse(null) is StaticJSClass, false);
+  expect(() => null as StaticJSClass,
+      hasUnsoundNullSafety ? returnsNormally : throws);
+
+  // Native objects can be interop'd with static interop classes.
+  expect(nativeClass is StaticNativeClass, true);
+  expect(confuse(nativeClass) is StaticNativeClass, true);
+  expect(() => nativeClass as StaticNativeClass, returnsNormally);
+
+  expect(staticNativeClass is NativeClass, true);
+  expect(confuse(staticNativeClass) is NativeClass, true);
+  expect(() => staticNativeClass as NativeClass, returnsNormally);
+
+  // Likewise, non-native JS objects can be interop'd with static interop
+  // classes as well.
+  expect(jsClass is StaticJSClass, true);
+  expect(confuse(jsClass) is StaticJSClass, true);
+  expect(() => jsClass as StaticJSClass, returnsNormally);
+
+  expect(staticJsClass is JSClass, true);
+  expect(confuse(staticJsClass) is JSClass, true);
+  expect(() => staticJsClass as JSClass, returnsNormally);
+
+  expect(anonymousClass is StaticJSClass, true);
+  expect(confuse(anonymousClass) is StaticJSClass, true);
+  expect(() => anonymousClass as StaticJSClass, returnsNormally);
+
+  expect(staticJsClass is AnonymousClass, true);
+  expect(confuse(staticJsClass) is AnonymousClass, true);
+  expect(() => staticJsClass as AnonymousClass, returnsNormally);
+
+  // With erasure, all static interop classes become the same type, so you can
+  // cast either interop or native objects to them regardless of the underlying
+  // class.
+  expect(staticNativeClass is StaticJSClass, true);
+  expect(confuse(staticNativeClass) is StaticJSClass, true);
+  expect(() => staticNativeClass as StaticJSClass, returnsNormally);
+
+  expect(staticJsClass is StaticNativeClass, true);
+  expect(confuse(staticJsClass) is StaticNativeClass, true);
+  expect(() => staticJsClass as StaticNativeClass, returnsNormally);
+
+  expect(nativeClass is StaticJSClass, true);
+  expect(confuse(nativeClass) is StaticJSClass, true);
+  expect(() => nativeClass as StaticJSClass, returnsNormally);
+
+  expect(jsClass is StaticNativeClass, true);
+  expect(confuse(jsClass) is StaticNativeClass, true);
+  expect(() => jsClass as StaticNativeClass, returnsNormally);
+
+  expect(anonymousClass is StaticNativeClass, true);
+  expect(confuse(anonymousClass) is StaticNativeClass, true);
+  expect(() => anonymousClass as StaticNativeClass, returnsNormally);
+
+  // You cannot, however, always cast from a static interop type to an interop
+  // type or a native type. That will depend on whether the object is an interop
+  // object or a native object.
+  expect(staticNativeClass is JSClass, false);
+  expect(confuse(staticNativeClass) is JSClass, false);
+  expect(() => staticNativeClass as JSClass, throws);
+
+  expect(staticNativeClass is AnonymousClass, false);
+  expect(confuse(staticNativeClass) is AnonymousClass, false);
+  expect(() => staticNativeClass as AnonymousClass, throws);
+
+  expect(staticJsClass is NativeClass, false);
+  expect(confuse(staticJsClass) is NativeClass, false);
+  expect(() => staticJsClass as NativeClass, throws);
+
+  // Subtyping rules.
+
+  // Note that erasure ignores all static class type parameters so this
+  // comparison becomes
+  // `JavaScriptObject Function() is JavaScriptObject Function()`. This behavior
+  // is similar to non-static interop classes.
+  expect(
+      returnGenericStaticJSClassInt is GenericStaticJSClass<String> Function(),
+      true);
+  expect(
+      confuse(returnGenericStaticJSClassInt) is GenericStaticJSClass<String>
+          Function(),
+      true);
+  expect(
+      () => returnGenericStaticJSClassInt as GenericStaticJSClass<String>
+          Function(),
+      returnsNormally);
+
+  // Test that nullability is respected.
+  expect(returnStaticJSClass is StaticJSClass? Function(), true);
+  expect(confuse(returnStaticJSClass) is StaticJSClass? Function(), true);
+  expect(returnNullableStaticJSClass is StaticJSClass Function(),
+      hasUnsoundNullSafety);
+  expect(confuse(returnNullableStaticJSClass) is StaticJSClass Function(),
+      hasUnsoundNullSafety);
+
+  // static interop class A <: static interop class A
+  expect(returnStaticNativeClass is StaticNativeClass Function(), true);
+  expect(
+      confuse(returnStaticNativeClass) is StaticNativeClass Function(), true);
+  expect(returnStaticJSClass is StaticJSClass Function(), true);
+  expect(confuse(returnStaticJSClass) is StaticJSClass Function(), true);
+
+  // static interop class A <: static interop class B
+  expect(returnStaticNativeClass is StaticJSClass Function(), true);
+  expect(confuse(returnStaticNativeClass) is StaticJSClass Function(), true);
+  expect(returnStaticJSClass is StaticNativeClass Function(), true);
+  expect(confuse(returnStaticJSClass) is StaticNativeClass Function(), true);
+
+  // static interop class !<: native class
+  expect(returnStaticNativeClass is NativeClass Function(), false);
+  expect(confuse(returnStaticNativeClass) is NativeClass Function(), false);
+  expect(returnStaticJSClass is NativeClass Function(), false);
+  expect(confuse(returnStaticJSClass) is NativeClass Function(), false);
+
+  // static interop class !<: package:js class
+  expect(returnStaticNativeClass is JSClass Function(), false);
+  expect(confuse(returnStaticNativeClass) is JSClass Function(), false);
+  expect(returnStaticJSClass is JSClass Function(), false);
+  expect(confuse(returnStaticJSClass) is JSClass Function(), false);
+
+  // static interop class !<: anonymous class
+  expect(returnStaticNativeClass is AnonymousClass Function(), false);
+  expect(confuse(returnStaticNativeClass) is AnonymousClass Function(), false);
+  expect(returnStaticJSClass is AnonymousClass Function(), false);
+  expect(confuse(returnStaticJSClass) is AnonymousClass Function(), false);
+
+  // native class <: static interop class
+  expect(returnNativeClass is StaticJSClass Function(), true);
+  expect(confuse(returnNativeClass) is StaticJSClass Function(), true);
+  expect(returnNativeClass is StaticNativeClass Function(), true);
+  expect(confuse(returnNativeClass) is StaticNativeClass Function(), true);
+
+  // package:js class <: static interop class
+  // TODO(46456): The runtime check using `confuse` does not fail, whereas the
+  // compile-time check does on dart2js.
+  // expect(returnJSClass is StaticJSClass Function(), true);
+  expect(confuse(returnJSClass) is StaticJSClass Function(), true);
+  // TODO(46456): The runtime check using `confuse` does not fail, whereas the
+  // compile-time check does on dart2js.
+  // expect(returnJSClass is StaticNativeClass Function(), true);
+  expect(confuse(returnJSClass) is StaticNativeClass Function(), true);
+
+  // anonymous class <: static interop class
+  // TODO(46456): The runtime check using `confuse` does not fail, whereas the
+  // compile-time check does on dart2js.
+  // expect(returnAnonymousClass is StaticJSClass Function(), true);
+  expect(confuse(returnAnonymousClass) is StaticJSClass Function(), true);
+  // TODO(46456): The runtime check using `confuse` does not fail, whereas the
+  // compile-time check does on dart2js.
+  // expect(returnAnonymousClass is StaticNativeClass Function(), true);
+  expect(confuse(returnAnonymousClass) is StaticNativeClass Function(), true);
+}
diff --git a/tests/web/native/static_interop_erasure/use_erased_type_members_test.dart b/tests/web/native/static_interop_erasure/use_erased_type_members_test.dart
new file mode 100644
index 0000000..99c446d
--- /dev/null
+++ b/tests/web/native/static_interop_erasure/use_erased_type_members_test.dart
@@ -0,0 +1,157 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// Test that a static interop class can be used in place of a Native class and
+// its static members work as expected post-erasure.
+
+@JS()
+library use_erased_type_members_test;
+
+import 'dart:_interceptors' show JavaScriptObject;
+
+import 'package:expect/minitest.dart';
+import 'package:js/js.dart';
+
+import '../native_testing.dart';
+import '../native_testing.dart' as native_testing;
+
+NativeClass makeNativeClass() native;
+
+@Native('NativeClass')
+class NativeClass extends JavaScriptObject {
+  factory NativeClass() => makeNativeClass();
+}
+
+@JS()
+@staticInterop
+class Parent {}
+
+extension ParentExtension on Parent {
+  external String parentExternalField;
+  external String get parentExternalGetSet;
+  external set parentExternalGetSet(String val);
+  external String parentExternalMethod();
+
+  String get parentGetSet => this.parentExternalGetSet;
+  set parentGetSet(String val) => this.parentExternalGetSet = val;
+  String parentMethod() => 'parentMethod';
+}
+
+@JS()
+@staticInterop
+class Interface {}
+
+extension InterfaceExtension on Interface {
+  external String interfaceExternalField;
+  external String get interfaceExternalGetSet;
+  external set interfaceExternalGetSet(String val);
+  external String interfaceExternalMethod();
+
+  String get interfaceGetSet => this.interfaceExternalGetSet;
+  set interfaceGetSet(String val) => this.interfaceExternalGetSet = val;
+  String interfaceMethod() => 'interfaceMethod';
+}
+
+@JS('NativeClass')
+@staticInterop
+class StaticJSClass extends Parent implements Interface {
+  external StaticJSClass();
+  external StaticJSClass.namedConstructor();
+  external factory StaticJSClass.externalFactory();
+  factory StaticJSClass.redirectingFactory() = StaticJSClass;
+
+  external static String externalStaticField;
+  external static String get externalStaticGetSet;
+  external static set externalStaticGetSet(String val);
+  external static String externalStaticMethod();
+}
+
+extension StaticJSClassExtension on StaticJSClass {
+  external String externalField;
+  external String get externalGetSet;
+  external set externalGetSet(String val);
+  external String externalMethod();
+
+  String get getSet => this.externalGetSet;
+  set getSet(String val) => this.externalGetSet = val;
+  String method() => 'method';
+}
+
+void main() {
+  nativeTesting();
+  native_testing.JS('', r'''
+    (function(){
+      function NativeClass() {
+        this.externalField = 'externalField';
+        this.externalGetSet = this.externalField;
+        this.externalMethod = function() { return 'externalMethod'; };
+
+        this.parentExternalField = 'parentExternalField';
+        this.parentExternalGetSet = this.parentExternalField;
+        this.parentExternalMethod = function() {
+          return 'parentExternalMethod';
+        };
+
+        this.interfaceExternalField = 'interfaceExternalField';
+        this.interfaceExternalGetSet = this.interfaceExternalField;
+        this.interfaceExternalMethod = function() {
+          return 'interfaceExternalMethod';
+        };
+      }
+      NativeClass.externalStaticField = 'externalStaticField';
+      NativeClass.externalStaticGetSet = NativeClass.externalStaticField;
+      NativeClass.externalStaticMethod = function() {
+        return 'externalStaticMethod';
+      };
+      self.NativeClass = NativeClass;
+      self.makeNativeClass = function(){return new NativeClass()};
+      self.nativeConstructor(NativeClass);
+    })()
+  ''');
+  applyTestExtensions(['NativeClass']);
+
+  // NativeClass needs to be live, so it can be correctly intercepted.
+  NativeClass();
+  // Invoke constructors and ensure they're typed correctly.
+  StaticJSClass staticJs = StaticJSClass();
+  staticJs = StaticJSClass.namedConstructor();
+  staticJs = StaticJSClass.externalFactory();
+  staticJs = StaticJSClass.redirectingFactory();
+
+  // Invoke external static members.
+  expect(StaticJSClass.externalStaticField, 'externalStaticField');
+  StaticJSClass.externalStaticGetSet = 'externalStaticGetSet';
+  expect(StaticJSClass.externalStaticGetSet, 'externalStaticGetSet');
+  expect(StaticJSClass.externalStaticMethod(), 'externalStaticMethod');
+
+  // Use extension members.
+  expect(staticJs.externalField, 'externalField');
+  staticJs.externalGetSet = 'externalGetSet';
+  expect(staticJs.externalGetSet, 'externalGetSet');
+  expect(staticJs.externalMethod(), 'externalMethod');
+
+  staticJs.getSet = 'getSet';
+  expect(staticJs.getSet, 'getSet');
+  expect(staticJs.method(), 'method');
+
+  // Use parent extension members.
+  expect(staticJs.parentExternalField, 'parentExternalField');
+  staticJs.parentExternalGetSet = 'parentExternalGetSet';
+  expect(staticJs.parentExternalGetSet, 'parentExternalGetSet');
+  expect(staticJs.parentExternalMethod(), 'parentExternalMethod');
+
+  staticJs.parentGetSet = 'parentGetSet';
+  expect(staticJs.parentGetSet, 'parentGetSet');
+  expect(staticJs.parentMethod(), 'parentMethod');
+
+  // Use interface extension members.
+  expect(staticJs.interfaceExternalField, 'interfaceExternalField');
+  staticJs.interfaceExternalGetSet = 'interfaceExternalGetSet';
+  expect(staticJs.interfaceExternalGetSet, 'interfaceExternalGetSet');
+  expect(staticJs.interfaceExternalMethod(), 'interfaceExternalMethod');
+
+  staticJs.interfaceGetSet = 'interfaceGetSet';
+  expect(staticJs.interfaceGetSet, 'interfaceGetSet');
+  expect(staticJs.interfaceMethod(), 'interfaceMethod');
+}
diff --git a/tests/web_2/internal/javascriptobject_extensions_test.dart b/tests/web_2/internal/javascriptobject_extensions_test.dart
index 6189667..dc912cd 100644
--- a/tests/web_2/internal/javascriptobject_extensions_test.dart
+++ b/tests/web_2/internal/javascriptobject_extensions_test.dart
@@ -11,9 +11,14 @@
 import 'package:js/js_util.dart';
 import 'package:expect/minitest.dart';
 
-import 'dart:typed_data';
+import 'dart:html' show Window;
+import 'dart:typed_data' show ByteBuffer;
 import 'dart:_interceptors'
-    show JavaScriptObject, UnknownJavaScriptObject, JSObject;
+    show
+        LegacyJavaScriptObject,
+        JavaScriptObject,
+        UnknownJavaScriptObject,
+        JSObject;
 
 @JS()
 external void eval(String code);
@@ -45,6 +50,11 @@
 @JS('arrayBuffer')
 external dynamic get arrayBufferDynamic;
 
+external Window get window;
+
+@JS('window')
+external dynamic get windowDynamic;
+
 // Extension on JavaScriptObject. In the future, when extension types are
 // introduced, this will be explicitly disallowed.
 extension JavaScriptObjectExtension on JavaScriptObject {
@@ -109,19 +119,33 @@
   expect(javaScriptObject is DartClass, false);
   runtimeIsAndAs<DartClass>(javaScriptObject, false);
 
-  // Native objects cannot be casted to or from JavaScriptObject.
+  // Web Native classes are subclasses of JavaScriptObject, but not
+  // LegacyJavaScriptObject.
+  expect(window is JavaScriptObject, true);
+  runtimeIsAndAs<JavaScriptObject>(window, true);
+  runtimeIsAndAs<JavaScriptObject>(windowDynamic, true);
+  javaScriptObject = jsObj as JavaScriptObject;
+  expect(javaScriptObject is Window, false);
+  runtimeIsAndAs<Window>(javaScriptObject, false);
+
+  expect(window is LegacyJavaScriptObject, false);
+  runtimeIsAndAs<LegacyJavaScriptObject>(window, false);
+  runtimeIsAndAs<LegacyJavaScriptObject>(windowDynamic, false);
+  var legacyJavaScriptObject = jsObj as LegacyJavaScriptObject;
+  expect(legacyJavaScriptObject is Window, false);
+  runtimeIsAndAs<Window>(legacyJavaScriptObject, false);
+
+  // Non-web Native classes like those in `dart:typed_data` are not subclasses
+  // of JavaScriptObject.
   expect(arrayBuffer is JavaScriptObject, false);
   runtimeIsAndAs<JavaScriptObject>(arrayBuffer, false);
+  runtimeIsAndAs<JavaScriptObject>(arrayBufferDynamic, false);
   expect(javaScriptObject is ByteBuffer, false);
   runtimeIsAndAs<ByteBuffer>(javaScriptObject, false);
 
-  // Dynamic native objects are intercepted and cannot be casted to
-  // JavaScriptObject.
-  runtimeIsAndAs<JavaScriptObject>(arrayBufferDynamic, false);
-
   // Make sure `Object` methods work with JavaScriptObject like they do with JS
   // interop objects.
-  expect(anonymousObj == javaScriptObject, true);
+  expect(javaScriptObject == jsObj, true);
   expect(javaScriptObject.hashCode, isNotNull);
   expect(javaScriptObject.toString, isNotNull);
   expect(javaScriptObject.noSuchMethod, isNotNull);
diff --git a/tests/web_2/internal/rti/js_interop_subtype_test.dart b/tests/web_2/internal/rti/js_interop_subtype_test.dart
index 66010da..ffcb31c 100644
--- a/tests/web_2/internal/rti/js_interop_subtype_test.dart
+++ b/tests/web_2/internal/rti/js_interop_subtype_test.dart
@@ -17,6 +17,6 @@
   eval(r'''
       function JSClass() {}
       ''');
-  Expect.type<JavaScriptObject>(JSClass());
-  Expect.type<List<JavaScriptObject>>(<JSClass>[]);
+  Expect.type<LegacyJavaScriptObject>(JSClass());
+  Expect.type<List<LegacyJavaScriptObject>>(<JSClass>[]);
 }
diff --git a/tests/web_2/native/error_safeToString_test.dart b/tests/web_2/native/error_safeToString_test.dart
index cc9acbc..c4d9df0 100644
--- a/tests/web_2/native/error_safeToString_test.dart
+++ b/tests/web_2/native/error_safeToString_test.dart
@@ -9,7 +9,7 @@
 import 'dart:_interceptors'
     show
         Interceptor,
-        JavaScriptObject,
+        LegacyJavaScriptObject,
         PlainJavaScriptObject,
         UnknownJavaScriptObject;
 
diff --git a/tests/web_2/native/jsobject_test.dart b/tests/web_2/native/jsobject_test.dart
index 5b8ed68..3631f85 100644
--- a/tests/web_2/native/jsobject_test.dart
+++ b/tests/web_2/native/jsobject_test.dart
@@ -10,7 +10,7 @@
     show
         JSObject, // The interface, which may be re-exported by a
         // js-interop library.
-        JavaScriptObject, //   The interceptor abstract class.
+        LegacyJavaScriptObject, //   The interceptor abstract class.
         PlainJavaScriptObject, //     The interceptor concrete class.
         UnknownJavaScriptObject, //     The interceptor concrete class.
         Interceptor;
@@ -49,21 +49,21 @@
 static_test() {
   var x = makeA();
   Expect.isTrue(x is JSObject);
-  Expect.isTrue(x is JavaScriptObject);
+  Expect.isTrue(x is LegacyJavaScriptObject);
   Expect.isTrue(x is PlainJavaScriptObject);
   Expect.isTrue(x is! UnknownJavaScriptObject);
   Expect.equals(JSObject, x.runtimeType);
 
   x = makeB();
   Expect.isTrue(x is JSObject);
-  Expect.isTrue(x is JavaScriptObject);
+  Expect.isTrue(x is LegacyJavaScriptObject);
   Expect.isTrue(x is! PlainJavaScriptObject);
   Expect.isTrue(x is UnknownJavaScriptObject);
   Expect.equals(JSObject, x.runtimeType);
 
   x = makeQ();
   Expect.isFalse(x is JSObject);
-  Expect.isFalse(x is JavaScriptObject);
+  Expect.isFalse(x is LegacyJavaScriptObject);
   Expect.isFalse(x is PlainJavaScriptObject);
   Expect.isFalse(x is UnknownJavaScriptObject);
   Expect.isFalse(x.runtimeType == JSObject);
@@ -73,27 +73,27 @@
 dynamic_test() {
   var x = makeA();
   var isJSObject = new Is<JSObject>().check;
-  var isJavaScriptObject = new Is<JavaScriptObject>().check;
+  var isLegacyJavaScriptObject = new Is<LegacyJavaScriptObject>().check;
   var isPlainJavaScriptObject = new Is<PlainJavaScriptObject>().check;
   var isUnknownJavaScriptObject = new Is<UnknownJavaScriptObject>().check;
   var isQ = new Is<Q>().check;
 
   Expect.isTrue(isJSObject(x));
-  Expect.isTrue(isJavaScriptObject(x));
+  Expect.isTrue(isLegacyJavaScriptObject(x));
   Expect.isTrue(isPlainJavaScriptObject(x));
   Expect.isTrue(!isUnknownJavaScriptObject(x));
   Expect.equals(JSObject, x.runtimeType);
 
   x = makeB();
   Expect.isTrue(isJSObject(x));
-  Expect.isTrue(isJavaScriptObject(x));
+  Expect.isTrue(isLegacyJavaScriptObject(x));
   Expect.isTrue(!isPlainJavaScriptObject(x));
   Expect.isTrue(isUnknownJavaScriptObject(x));
   Expect.equals(JSObject, x.runtimeType);
 
   x = makeQ();
   Expect.isFalse(isJSObject(x));
-  Expect.isFalse(isJavaScriptObject(x));
+  Expect.isFalse(isLegacyJavaScriptObject(x));
   Expect.isFalse(isPlainJavaScriptObject(x));
   Expect.isFalse(isUnknownJavaScriptObject(x));
   Expect.isTrue(isQ(x));
diff --git a/tests/web_2/native/static_interop_erasure/factory_stub_test.dart b/tests/web_2/native/static_interop_erasure/factory_stub_test.dart
new file mode 100644
index 0000000..8aba8f4
--- /dev/null
+++ b/tests/web_2/native/static_interop_erasure/factory_stub_test.dart
@@ -0,0 +1,75 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// @dart = 2.7
+
+// Test that factory methods with bodies are stubbed correctly in static interop
+// type erasure.
+
+@JS()
+library factory_stub_test;
+
+import 'dart:_interceptors' show JavaScriptObject;
+
+import 'package:js/js.dart';
+
+import '../native_testing.dart';
+import '../native_testing.dart' as native_testing;
+
+NativeClass makeNativeClass() native;
+
+@Native('NativeClass')
+class NativeClass extends JavaScriptObject {
+  factory NativeClass() => makeNativeClass();
+}
+
+@JS('NativeClass')
+@staticInterop
+class StaticNativeClass {
+  external StaticNativeClass();
+  factory StaticNativeClass.redirectingFactory() = StaticNativeClass;
+  factory StaticNativeClass.simpleFactory() => StaticNativeClass();
+  factory StaticNativeClass.factoryWithParam(
+          StaticNativeClass staticNativeClass) =>
+      staticNativeClass;
+  // This and `StaticNativeClassCopy.nestedFactory` exist to ensure that we
+  // cover the case where invocations on factories are visible before their
+  // declarations in the AST. This will test whether we correctly create the
+  // stub even if we haven't visited the declaration yet.
+  factory StaticNativeClass.nestedFactory() {
+    StaticNativeClassCopy.nestedFactory();
+    return StaticNativeClass();
+  }
+}
+
+@JS('NativeClass')
+@staticInterop
+class StaticNativeClassCopy {
+  external StaticNativeClassCopy();
+  factory StaticNativeClassCopy.nestedFactory() {
+    StaticNativeClass.simpleFactory();
+    return StaticNativeClassCopy();
+  }
+}
+
+void main() {
+  nativeTesting();
+  native_testing.JS('', r'''
+    (function(){
+      function NativeClass() {}
+      self.NativeClass = NativeClass;
+      self.makeNativeClass = function(){return new NativeClass()};
+      self.nativeConstructor(NativeClass);
+    })()
+  ''');
+  applyTestExtensions(['NativeClass']);
+
+  // Make the Native class live.
+  NativeClass();
+  // Invoke factories and ensure they're typed correctly through assignment.
+  StaticNativeClass staticNativeClass = StaticNativeClass.redirectingFactory();
+  staticNativeClass = StaticNativeClass.simpleFactory();
+  staticNativeClass = StaticNativeClass.factoryWithParam(staticNativeClass);
+  staticNativeClass = StaticNativeClass.nestedFactory();
+}
diff --git a/tests/web_2/native/static_interop_erasure/type_test.dart b/tests/web_2/native/static_interop_erasure/type_test.dart
new file mode 100644
index 0000000..5d85ebb
--- /dev/null
+++ b/tests/web_2/native/static_interop_erasure/type_test.dart
@@ -0,0 +1,226 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// @dart = 2.7
+
+// Test that the type and subtyping relationships between static interop,
+// non-static interop, and Native classes are well-formed.
+
+@JS()
+library type_test;
+
+import 'dart:_interceptors' show JavaScriptObject;
+
+import 'package:expect/minitest.dart';
+import 'package:js/js.dart';
+
+import '../native_testing.dart';
+import '../native_testing.dart' as native_testing;
+
+NativeClass makeNativeClass() native;
+
+@Native('NativeClass')
+class NativeClass extends JavaScriptObject {
+  factory NativeClass() => makeNativeClass();
+}
+
+@JS('NativeClass')
+@staticInterop
+class StaticNativeClass {
+  external StaticNativeClass();
+}
+
+@JS()
+class JSClass {
+  external JSClass();
+}
+
+@JS('JSClass')
+@staticInterop
+class StaticJSClass {
+  external StaticJSClass();
+}
+
+@JS()
+@anonymous
+class AnonymousClass {
+  external factory();
+}
+
+@JS()
+@staticInterop
+class GenericStaticJSClass<T> {}
+
+NativeClass returnNativeClass() => throw '';
+
+StaticNativeClass returnStaticNativeClass() => throw '';
+
+JSClass returnJSClass() => throw '';
+
+StaticJSClass returnStaticJSClass() => throw '';
+
+AnonymousClass returnAnonymousClass() => throw '';
+
+GenericStaticJSClass<int> returnGenericStaticJSClassInt() => throw '';
+
+void main() {
+  nativeTesting();
+  native_testing.JS('', r'''
+    (function(){
+      function NativeClass() {}
+      self.NativeClass = NativeClass;
+      self.makeNativeClass = function(){return new NativeClass()};
+      self.nativeConstructor(NativeClass);
+      function JSClass() {}
+      self.JSClass = JSClass;
+    })()
+  ''');
+  applyTestExtensions(['NativeClass']);
+
+  var nativeClass = NativeClass();
+  var staticNativeClass = StaticNativeClass();
+  var jsClass = JSClass();
+  var staticJsClass = StaticJSClass();
+  var anonymousClass = AnonymousClass();
+
+  // Native objects can be interop'd with static interop classes.
+  expect(nativeClass is StaticNativeClass, true);
+  expect(confuse(nativeClass) is StaticNativeClass, true);
+  expect(() => nativeClass as StaticNativeClass, returnsNormally);
+
+  expect(staticNativeClass is NativeClass, true);
+  expect(confuse(staticNativeClass) is NativeClass, true);
+  expect(() => staticNativeClass as NativeClass, returnsNormally);
+
+  // Likewise, non-native JS objects can be interop'd with static interop
+  // classes as well.
+  expect(jsClass is StaticJSClass, true);
+  expect(confuse(jsClass) is StaticJSClass, true);
+  expect(() => jsClass as StaticJSClass, returnsNormally);
+
+  expect(staticJsClass is JSClass, true);
+  expect(confuse(staticJsClass) is JSClass, true);
+  expect(() => staticJsClass as JSClass, returnsNormally);
+
+  expect(anonymousClass is StaticJSClass, true);
+  expect(confuse(anonymousClass) is StaticJSClass, true);
+  expect(() => anonymousClass as StaticJSClass, returnsNormally);
+
+  expect(staticJsClass is AnonymousClass, true);
+  expect(confuse(staticJsClass) is AnonymousClass, true);
+  expect(() => staticJsClass as AnonymousClass, returnsNormally);
+
+  // With erasure, all static interop classes become the same type, so you can
+  // cast either interop or native objects to them regardless of the underlying
+  // class.
+  expect(staticNativeClass is StaticJSClass, true);
+  expect(confuse(staticNativeClass) is StaticJSClass, true);
+  expect(() => staticNativeClass as StaticJSClass, returnsNormally);
+
+  expect(staticJsClass is StaticNativeClass, true);
+  expect(confuse(staticJsClass) is StaticNativeClass, true);
+  expect(() => staticJsClass as StaticNativeClass, returnsNormally);
+
+  expect(nativeClass is StaticJSClass, true);
+  expect(confuse(nativeClass) is StaticJSClass, true);
+  expect(() => nativeClass as StaticJSClass, returnsNormally);
+
+  expect(jsClass is StaticNativeClass, true);
+  expect(confuse(jsClass) is StaticNativeClass, true);
+  expect(() => jsClass as StaticNativeClass, returnsNormally);
+
+  expect(anonymousClass is StaticNativeClass, true);
+  expect(confuse(anonymousClass) is StaticNativeClass, true);
+  expect(() => anonymousClass as StaticNativeClass, returnsNormally);
+
+  // You cannot, however, always cast from a static interop type to an interop
+  // type or a native type. That will depend on whether the object is an interop
+  // object or a native object.
+  expect(staticNativeClass is JSClass, false);
+  expect(confuse(staticNativeClass) is JSClass, false);
+  expect(() => staticNativeClass as JSClass, throws);
+
+  expect(staticNativeClass is AnonymousClass, false);
+  expect(confuse(staticNativeClass) is AnonymousClass, false);
+  expect(() => staticNativeClass as AnonymousClass, throws);
+
+  expect(staticJsClass is NativeClass, false);
+  expect(confuse(staticJsClass) is NativeClass, false);
+  expect(() => staticJsClass as NativeClass, throws);
+
+  // Subtyping rules.
+
+  // Note that erasure ignores all static class type parameters so this
+  // comparison becomes
+  // `JavaScriptObject Function() is JavaScriptObject Function()`. This behavior
+  // is similar to non-static interop classes.
+  expect(
+      returnGenericStaticJSClassInt is GenericStaticJSClass<String> Function(),
+      true);
+  expect(
+      confuse(returnGenericStaticJSClassInt) is GenericStaticJSClass<String>
+          Function(),
+      true);
+  expect(
+      () => returnGenericStaticJSClassInt as GenericStaticJSClass<String>
+          Function(),
+      returnsNormally);
+
+  // static interop class A <: static interop class A
+  expect(returnStaticNativeClass is StaticNativeClass Function(), true);
+  expect(
+      confuse(returnStaticNativeClass) is StaticNativeClass Function(), true);
+  expect(returnStaticJSClass is StaticJSClass Function(), true);
+  expect(confuse(returnStaticJSClass) is StaticJSClass Function(), true);
+
+  // static interop class A <: static interop class B
+  expect(returnStaticNativeClass is StaticJSClass Function(), true);
+  expect(confuse(returnStaticNativeClass) is StaticJSClass Function(), true);
+  expect(returnStaticJSClass is StaticNativeClass Function(), true);
+  expect(confuse(returnStaticJSClass) is StaticNativeClass Function(), true);
+
+  // static interop class !<: native class
+  expect(returnStaticNativeClass is NativeClass Function(), false);
+  expect(confuse(returnStaticNativeClass) is NativeClass Function(), false);
+  expect(returnStaticJSClass is NativeClass Function(), false);
+  expect(confuse(returnStaticJSClass) is NativeClass Function(), false);
+
+  // static interop class !<: package:js class
+  expect(returnStaticNativeClass is JSClass Function(), false);
+  expect(confuse(returnStaticNativeClass) is JSClass Function(), false);
+  expect(returnStaticJSClass is JSClass Function(), false);
+  expect(confuse(returnStaticJSClass) is JSClass Function(), false);
+
+  // static interop class !<: anonymous class
+  expect(returnStaticNativeClass is AnonymousClass Function(), false);
+  expect(confuse(returnStaticNativeClass) is AnonymousClass Function(), false);
+  expect(returnStaticJSClass is AnonymousClass Function(), false);
+  expect(confuse(returnStaticJSClass) is AnonymousClass Function(), false);
+
+  // native class <: static interop class
+  expect(returnNativeClass is StaticJSClass Function(), true);
+  expect(confuse(returnNativeClass) is StaticJSClass Function(), true);
+  expect(returnNativeClass is StaticNativeClass Function(), true);
+  expect(confuse(returnNativeClass) is StaticNativeClass Function(), true);
+
+  // package:js class <: static interop class
+  // TODO(46456): The runtime check using `confuse` does not fail, whereas the
+  // compile-time check does on dart2js.
+  // expect(returnJSClass is StaticJSClass Function(), true);
+  expect(confuse(returnJSClass) is StaticJSClass Function(), true);
+  // TODO(46456): The runtime check using `confuse` does not fail, whereas the
+  // compile-time check does on dart2js.
+  // expect(returnJSClass is StaticNativeClass Function(), true);
+  expect(confuse(returnJSClass) is StaticNativeClass Function(), true);
+
+  // anonymous class <: static interop class
+  // TODO(46456): The runtime check using `confuse` does not fail, whereas the
+  // compile-time check does on dart2js.
+  // expect(returnAnonymousClass is StaticJSClass Function(), true);
+  expect(confuse(returnAnonymousClass) is StaticJSClass Function(), true);
+  // TODO(46456): The runtime check using `confuse` does not fail, whereas the
+  // compile-time check does on dart2js.
+  // expect(returnAnonymousClass is StaticNativeClass Function(), true);
+  expect(confuse(returnAnonymousClass) is StaticNativeClass Function(), true);
+}
diff --git a/tests/web_2/native/static_interop_erasure/use_erased_type_members_test.dart b/tests/web_2/native/static_interop_erasure/use_erased_type_members_test.dart
new file mode 100644
index 0000000..22ad0c3
--- /dev/null
+++ b/tests/web_2/native/static_interop_erasure/use_erased_type_members_test.dart
@@ -0,0 +1,148 @@
+// Copyright (c) 2021, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// @dart = 2.7
+
+// Test that a static interop class can be used in place of a Native class and
+// its static members work as expected post-erasure.
+
+@JS()
+library use_erased_type_members_test;
+
+import 'dart:_interceptors' show JavaScriptObject;
+
+import 'package:expect/minitest.dart';
+import 'package:js/js.dart';
+
+import '../native_testing.dart';
+import '../native_testing.dart' as native_testing;
+
+NativeClass makeNativeClass() native;
+
+@Native('NativeClass')
+class NativeClass extends JavaScriptObject {
+  factory NativeClass() => makeNativeClass();
+}
+
+@JS()
+@staticInterop
+class Parent {}
+
+extension ParentExtension on Parent {
+  external String get parentExternalGetSet;
+  external set parentExternalGetSet(String val);
+  external String parentExternalMethod();
+
+  String get parentGetSet => this.parentExternalGetSet;
+  set parentGetSet(String val) => this.parentExternalGetSet = val;
+  String parentMethod() => 'parentMethod';
+}
+
+@JS()
+@staticInterop
+class Interface {}
+
+extension InterfaceExtension on Interface {
+  external String get interfaceExternalGetSet;
+  external set interfaceExternalGetSet(String val);
+  external String interfaceExternalMethod();
+
+  String get interfaceGetSet => this.interfaceExternalGetSet;
+  set interfaceGetSet(String val) => this.interfaceExternalGetSet = val;
+  String interfaceMethod() => 'interfaceMethod';
+}
+
+@JS('NativeClass')
+@staticInterop
+class StaticJSClass extends Parent implements Interface {
+  external StaticJSClass();
+  external StaticJSClass.namedConstructor();
+  external factory StaticJSClass.externalFactory();
+  factory StaticJSClass.redirectingFactory() = StaticJSClass;
+
+  external static String get externalStaticGetSet;
+  external static set externalStaticGetSet(String val);
+  external static String externalStaticMethod();
+}
+
+extension StaticJSClassExtension on StaticJSClass {
+  external String get externalGetSet;
+  external set externalGetSet(String val);
+  external String externalMethod();
+
+  String get getSet => this.externalGetSet;
+  set getSet(String val) => this.externalGetSet = val;
+  String method() => 'method';
+}
+
+void main() {
+  nativeTesting();
+  native_testing.JS('', r'''
+    (function(){
+      function NativeClass() {
+        this.externalGetSet = '';
+        this.externalMethod = function() { return 'externalMethod'; };
+
+        this.parentExternalGetSet = '';
+        this.parentExternalMethod = function() {
+          return 'parentExternalMethod';
+        };
+
+        this.interfaceExternalGetSet = '';
+        this.interfaceExternalMethod = function() {
+          return 'interfaceExternalMethod';
+        };
+      }
+      NativeClass.externalStaticField = 'externalStaticField';
+      NativeClass.externalStaticGetSet = NativeClass.externalStaticField;
+      NativeClass.externalStaticMethod = function() {
+        return 'externalStaticMethod';
+      };
+      self.NativeClass = NativeClass;
+      self.makeNativeClass = function(){return new NativeClass()};
+      self.nativeConstructor(NativeClass);
+    })()
+  ''');
+  applyTestExtensions(['NativeClass']);
+
+  // NativeClass needs to be live, so it can be correctly intercepted.
+  NativeClass();
+  // Invoke constructors and ensure they're typed correctly.
+  StaticJSClass staticJs = StaticJSClass();
+  staticJs = StaticJSClass.namedConstructor();
+  staticJs = StaticJSClass.externalFactory();
+  staticJs = StaticJSClass.redirectingFactory();
+
+  // Invoke external static members.
+  StaticJSClass.externalStaticGetSet = 'externalStaticGetSet';
+  expect(StaticJSClass.externalStaticGetSet, 'externalStaticGetSet');
+  expect(StaticJSClass.externalStaticMethod(), 'externalStaticMethod');
+
+  // Use extension members.
+  staticJs.externalGetSet = 'externalGetSet';
+  expect(staticJs.externalGetSet, 'externalGetSet');
+  expect(staticJs.externalMethod(), 'externalMethod');
+
+  staticJs.getSet = 'getSet';
+  expect(staticJs.getSet, 'getSet');
+  expect(staticJs.method(), 'method');
+
+  // Use parent extension members.
+  staticJs.parentExternalGetSet = 'parentExternalGetSet';
+  expect(staticJs.parentExternalGetSet, 'parentExternalGetSet');
+  expect(staticJs.parentExternalMethod(), 'parentExternalMethod');
+
+  staticJs.parentGetSet = 'parentGetSet';
+  expect(staticJs.parentGetSet, 'parentGetSet');
+  expect(staticJs.parentMethod(), 'parentMethod');
+
+  // Use interface extension members.
+  staticJs.interfaceExternalGetSet = 'interfaceExternalGetSet';
+  expect(staticJs.interfaceExternalGetSet, 'interfaceExternalGetSet');
+  expect(staticJs.interfaceExternalMethod(), 'interfaceExternalMethod');
+
+  staticJs.interfaceGetSet = 'interfaceGetSet';
+  expect(staticJs.interfaceGetSet, 'interfaceGetSet');
+  expect(staticJs.interfaceMethod(), 'interfaceMethod');
+}
diff --git a/tools/VERSION b/tools/VERSION
index f44f6d8..4e66be2 100644
--- a/tools/VERSION
+++ b/tools/VERSION
@@ -27,5 +27,5 @@
 MAJOR 2
 MINOR 16
 PATCH 0
-PRERELEASE 80
+PRERELEASE 134
 PRERELEASE_PATCH 1
\ No newline at end of file
diff --git a/tools/bots/flutter/analyze_flutter_flutter.sh b/tools/bots/flutter/analyze_flutter_flutter.sh
index cd50561..fbfb264 100755
--- a/tools/bots/flutter/analyze_flutter_flutter.sh
+++ b/tools/bots/flutter/analyze_flutter_flutter.sh
@@ -39,4 +39,4 @@
 $dart fix packages/flutter/test_fixes --compare-to-golden
 
 # Analyze the sample code in dartdoc snippets.
-$dart dev/bots/analyze_sample_code.dart
+PUB_CACHE=$checkout/.pub_cache $dart dev/bots/analyze_sample_code.dart
diff --git a/tools/bots/flutter/analyze_flutter_gallery.sh b/tools/bots/flutter/analyze_flutter_gallery.sh
new file mode 100755
index 0000000..38dd5f7
--- /dev/null
+++ b/tools/bots/flutter/analyze_flutter_gallery.sh
@@ -0,0 +1,34 @@
+#!/usr/bin/env bash
+# Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
+# for details. All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE file.
+
+# Analyze Dart code in the flutter/gallery repo.
+
+set -ex
+
+checkout=$(pwd)
+dart=$checkout/out/ReleaseX64/dart-sdk/bin/dart
+sdk=$checkout/out/ReleaseX64/dart-sdk
+tmpdir=$(mktemp -d)
+cleanup() {
+  rm -rf "$tmpdir"
+}
+trap cleanup EXIT HUP INT QUIT TERM PIPE
+cd "$tmpdir"
+
+# install flutter
+git clone --single-branch -vv https://github.com/flutter/flutter
+export PATH="$PATH":"$tmpdir/flutter/bin"
+flutter --version
+
+git clone --single-branch -vv \
+  https://dart.googlesource.com/external/github.com/flutter/gallery
+
+cd gallery
+
+# analyze
+echo Analyzing...
+
+flutter packages get
+$dart analyze --fatal-infos
diff --git a/tools/bots/flutter/compile_flutter.sh b/tools/bots/flutter/compile_flutter.sh
index 511855c..35d271f 100755
--- a/tools/bots/flutter/compile_flutter.sh
+++ b/tools/bots/flutter/compile_flutter.sh
@@ -73,6 +73,7 @@
 pushd src
 git clone --single-branch --depth=1 -vv \
     https://dart.googlesource.com/external/github.com/flutter/engine flutter
+mkdir -p third_party
 pushd third_party
 ln -s $checkout dart
 popd  # third_party
diff --git a/tools/bots/test_matrix.json b/tools/bots/test_matrix.json
index c060e70..ed2057e 100644
--- a/tools/bots/test_matrix.json
+++ b/tools/bots/test_matrix.json
@@ -544,10 +544,7 @@
     },
     "dart2js-(linux|mac|win)-chrome": {
       "options": {
-        "use-sdk": true,
-        "dart2js-options": [
-          "--canary"
-        ]
+        "use-sdk": true
       }
     },
     "dart2js-(linux|mac|win)-chrome-unsound": {
@@ -691,10 +688,20 @@
         ]
       }
     },
-    "dart2js-modern-(linux|mac|win)-d8": {
+    "dart2js-canary-(linux|mac|win)-d8": {
       "options": {
-        "builder-tag": "dart2js_modern",
-        "use-sdk": true,
+        "builder-tag": "dart2js_canary",
+        "host-checked": true,
+        "timeout": 240,
+        "dart2js-options": [
+          "--canary"
+        ]
+      }
+    },
+    "dart2js-canary-(linux|mac|win)-chrome": {
+      "options": {
+        "host-checked": true,
+        "timeout": 240,
         "dart2js-options": [
           "--canary"
         ]
@@ -793,7 +800,8 @@
     },
     "dartkp-linux-(debug|product|release)-simarm-crossword": {
       "options": {
-        "builder-tag": "crossword"
+        "builder-tag": "crossword",
+        "use-elf": true
       }
     },
     "dartkp-weak-asserts-linux-(debug|product|release)-simarm-crossword": {
@@ -2398,6 +2406,62 @@
     },
     {
       "builders": [
+        "dart2js-canary-x64"
+      ],
+      "meta": {
+        "description": "dart2js canary tests."
+      },
+      "steps": [
+        {
+          "name": "build dart",
+          "script": "tools/build.py",
+          "arguments": [
+            "create_sdk",
+            "dart2js_bot"
+          ]
+        },
+        {
+          "name": "dart2js canary d8 tests",
+          "arguments": [
+            "-ndart2js-canary-linux-d8",
+            "language",
+            "corelib",
+            "web"
+          ],
+          "shards": 6,
+          "fileset": "web_platform_hostasserts_nnbd"
+        },
+        {
+          "name": "dart2js canary chrome tests",
+          "arguments": [
+            "-ndart2js-canary-linux-chrome",
+            "web"
+          ],
+          "shards": 3,
+          "fileset": "web_platform_hostasserts_nnbd"
+        },
+        {
+          "name": "dart2js canary lib tests",
+          "arguments": [
+            "-ndart2js-canary-linux-chrome",
+            "lib"
+          ],
+          "shards": 3,
+          "fileset": "web_platform_hostasserts_nnbd"
+        },
+        {
+          "name": "dart2js canary co19 tests",
+          "arguments": [
+            "-ndart2js-canary-linux-chrome",
+            "co19"
+          ],
+          "shards": 6,
+          "fileset": "web_platform_hostasserts_nnbd"
+        }
+      ]
+    },
+    {
+      "builders": [
         "dart2js-unit-linux-x64-release"
       ],
       "meta": {
@@ -2644,13 +2708,6 @@
           ]
         },
         {
-          "name": "dart2js --canary smoke tests",
-          "arguments": [
-            "-ndart2js-modern-linux-d8",
-            "web_2"
-          ]
-        },
-        {
           "name": "dart2js d8 fragment merging tests",
           "arguments": [
             "-ndart2js-minified-hostasserts-weak-max-fragments-linux-x64-d8",
@@ -3699,6 +3756,10 @@
         {
           "name": "analyze flutter/plugins",
           "script": "tools/bots/flutter/analyze_flutter_plugins.sh"
+        },
+        {
+          "name": "analyze flutter/gallery",
+          "script": "tools/bots/flutter/analyze_flutter_gallery.sh"
         }
       ]
     },
diff --git a/tools/dom/scripts/CSSPropertyNames.in b/tools/dom/scripts/CSSPropertyNames.in
index 39b49ad..8947335 100644
--- a/tools/dom/scripts/CSSPropertyNames.in
+++ b/tools/dom/scripts/CSSPropertyNames.in
@@ -288,7 +288,8 @@
 -webkit-column-break-inside
 -webkit-column-count
 column-fill
--webkit-column-gap
+column-gap
+-webkit-column-gap alias_for=column-gap
 -webkit-column-rule
 -webkit-column-rule-color
 -webkit-column-rule-style
@@ -321,6 +322,7 @@
 justify-content
 -webkit-justify-content alias_for=justify-content
 -webkit-font-size-delta
+gap
 grid-auto-columns
 grid-auto-flow
 grid-auto-rows
@@ -387,6 +389,7 @@
 -webkit-perspective-origin-x
 -webkit-perspective-origin-y
 -webkit-print-color-adjust
+row-gap
 -webkit-rtl-ordering
 -webkit-ruby-position
 -webkit-text-combine
diff --git a/tools/dom/scripts/generator.py b/tools/dom/scripts/generator.py
index bcc36f3..6ac22ce 100644
--- a/tools/dom/scripts/generator.py
+++ b/tools/dom/scripts/generator.py
@@ -293,8 +293,23 @@
         'CSSStyleDeclaration,MSStyleCSSProperties,CSS2Properties',
         'ApplicationCache':
         'ApplicationCache,DOMApplicationCache,OfflineResourceList',
+        'DirectoryEntry':
+        #Chrome         Edge/Opera
+        'DirectoryEntry,webkitFileSystemDirectoryEntry,FileSystemDirectoryEntry',
+        'DirectoryReader':
+        #Chrome          Edge                  Opera
+        'DirectoryReader,WebKitDirectoryReader,webkitFileSystemDirectoryReader,FileSystemDirectoryReader',
+        'DOMFileSystem':
+        #Chrome        Edge             Opera
+        'DOMFileSystem,WebKitFileSystem,webkitFileSystem,FileSystem',
+        'Entry':
+        #Chrome Edge
+        'Entry,webkitFileSystemEntry,FileSystemEntry',
         'Event':
         'Event,InputEvent,SubmitEvent',  # Workaround for issue 40901.
+        'FileEntry':
+        #Chrome    Edge
+        'FileEntry,webkitFileSystemFileEntry,FileSystemFileEntry',
         'HTMLTableCellElement':
         'HTMLTableCellElement,HTMLTableDataCellElement,HTMLTableHeaderCellElement',
         'GainNode':
diff --git a/tools/dom/scripts/htmlrenamer.py b/tools/dom/scripts/htmlrenamer.py
index 7e84e7c..30fa1af 100644
--- a/tools/dom/scripts/htmlrenamer.py
+++ b/tools/dom/scripts/htmlrenamer.py
@@ -268,6 +268,8 @@
             'getDirectory': [''],
             'getFile': [
                 'applyExtension(\'FileEntry\', value);',
+                'applyExtension(\'webkitFileSystemFileEntry\', value);',
+                'applyExtension(\'FileSystemFileEntry\', value);',
             ]
         },
         'Entry': {
@@ -276,6 +278,8 @@
             ],
             'getParent': [
                 'applyExtension(\'Entry\', value);',
+                'applyExtension(\'webkitFileSystemEntry\', value);',
+                'applyExtension(\'FileSystemEntry\', value);',
             ]
         },
         'FileEntry': {
@@ -291,7 +295,12 @@
         'Window': {
             'webkitRequestFileSystem': [
                 'applyExtension(\'DOMFileSystem\', value);',
+                'applyExtension(\'WebKitFileSystem\', value);',
+                'applyExtension(\'webkitFileSystem\', value);',
+                'applyExtension(\'FileSystem\', value);',
                 'applyExtension(\'DirectoryEntry\', value.root);',
+                'applyExtension(\'webkitFileSystemDirectoryEntry\', value.root);',
+                'applyExtension(\'FileSystemDirectoryEntry\', value.root);',
             ]
         },
     })
diff --git a/tools/dom/scripts/systemhtml.py b/tools/dom/scripts/systemhtml.py
index 9fa35dc..63d913e 100644
--- a/tools/dom/scripts/systemhtml.py
+++ b/tools/dom/scripts/systemhtml.py
@@ -732,7 +732,7 @@
         if mixins:
             mixins_str = ' with ' + ', '.join(mixins)
             if not base_class:
-                base_class = 'Interceptor'
+                base_class = 'JavaScriptObject'
             elif (base_class == 'NativeFieldWrapperClass2' and
                   self._options.dart_js_interop and
                   not (isinstance(self._backend, Dart2JSBackend))):
@@ -1831,7 +1831,7 @@
         pass
 
     def RootClassName(self):
-        return 'Interceptor'
+        return 'JavaScriptObject'
 
     def OmitOperationOverrides(self):
         return True
diff --git a/tools/dom/templates/html/dart2js/html_dart2js.darttemplate b/tools/dom/templates/html/dart2js/html_dart2js.darttemplate
index b3dc526..c185ef7 100644
--- a/tools/dom/templates/html/dart2js/html_dart2js.darttemplate
+++ b/tools/dom/templates/html/dart2js/html_dart2js.darttemplate
@@ -45,7 +45,7 @@
     findDispatchTagForInterceptorClass, setNativeSubclassDispatchRecord,
     makeLeafDispatchRecord, registerGlobalObject, applyExtension;
 import 'dart:_interceptors' show
-    Interceptor, JavaScriptFunction, JSExtendableArray, JSUInt31,
+    JavaScriptObject, JavaScriptFunction, JSExtendableArray, JSUInt31,
     findInterceptorConstructorForType,
     findConstructorForNativeSubclassType,
     getNativeInterceptor,
diff --git a/tools/dom/templates/html/dart2js/indexed_db_dart2js.darttemplate b/tools/dom/templates/html/dart2js/indexed_db_dart2js.darttemplate
index 8373820..2bfbeeb 100644
--- a/tools/dom/templates/html/dart2js/indexed_db_dart2js.darttemplate
+++ b/tools/dom/templates/html/dart2js/indexed_db_dart2js.darttemplate
@@ -83,7 +83,7 @@
 import 'dart:typed_data';
 import 'dart:_js_helper' show Creates, Returns, JSName, Native;
 import 'dart:_foreign_helper' show JS;
-import 'dart:_interceptors' show Interceptor, JSExtendableArray;
+import 'dart:_interceptors' show JavaScriptObject, JSExtendableArray;
 
 import 'dart:_js_helper' show convertDartClosureToJS;
 
diff --git a/tools/dom/templates/html/dart2js/svg_dart2js.darttemplate b/tools/dom/templates/html/dart2js/svg_dart2js.darttemplate
index e2f72ee..c7f153a 100644
--- a/tools/dom/templates/html/dart2js/svg_dart2js.darttemplate
+++ b/tools/dom/templates/html/dart2js/svg_dart2js.darttemplate
@@ -21,7 +21,7 @@
 import 'dart:html_common';
 import 'dart:_js_helper' show Creates, Returns, JSName, Native;
 import 'dart:_foreign_helper' show JS;
-import 'dart:_interceptors' show Interceptor;
+import 'dart:_interceptors' show JavaScriptObject;
 
 part '$AUXILIARY_DIR/shared_SVGFactoryProviders.dart';
 
diff --git a/tools/dom/templates/html/dart2js/web_audio_dart2js.darttemplate b/tools/dom/templates/html/dart2js/web_audio_dart2js.darttemplate
index 31437b3..44c468f 100644
--- a/tools/dom/templates/html/dart2js/web_audio_dart2js.darttemplate
+++ b/tools/dom/templates/html/dart2js/web_audio_dart2js.darttemplate
@@ -20,6 +20,6 @@
     Creates, JavaScriptIndexingBehavior, JSName, Native, Returns,
     convertDartClosureToJS;
 import 'dart:_foreign_helper' show JS;
-import 'dart:_interceptors' show Interceptor;
+import 'dart:_interceptors' show JavaScriptObject;
 
 $!GENERATED_DART_FILES
diff --git a/tools/dom/templates/html/dart2js/web_gl_dart2js.darttemplate b/tools/dom/templates/html/dart2js/web_gl_dart2js.darttemplate
index 8780f3a..5b2fc8cf 100644
--- a/tools/dom/templates/html/dart2js/web_gl_dart2js.darttemplate
+++ b/tools/dom/templates/html/dart2js/web_gl_dart2js.darttemplate
@@ -18,6 +18,6 @@
 import 'dart:typed_data';
 import 'dart:_js_helper' show Creates, JSName, Native, Returns, convertDartClosureToJS;
 import 'dart:_foreign_helper' show JS;
-import 'dart:_interceptors' show Interceptor, JSExtendableArray;
+import 'dart:_interceptors' show JavaScriptObject, JSExtendableArray;
 
 $!GENERATED_DART_FILES
diff --git a/tools/dom/templates/html/dart2js/web_sql_dart2js.darttemplate b/tools/dom/templates/html/dart2js/web_sql_dart2js.darttemplate
index 8877f95..9c25d0a 100644
--- a/tools/dom/templates/html/dart2js/web_sql_dart2js.darttemplate
+++ b/tools/dom/templates/html/dart2js/web_sql_dart2js.darttemplate
@@ -26,6 +26,6 @@
 import 'dart:_js_helper' show applyExtension, convertDartClosureToJS, Creates,
     JSName, Native, JavaScriptIndexingBehavior, Returns;
 import 'dart:_foreign_helper' show JS;
-import 'dart:_interceptors' show Interceptor;
+import 'dart:_interceptors' show JavaScriptObject;
 
 $!GENERATED_DART_FILES
diff --git a/tools/dom/templates/html/impl/impl_CSSStyleDeclaration.darttemplate b/tools/dom/templates/html/impl/impl_CSSStyleDeclaration.darttemplate
index 914faca..7aade98 100644
--- a/tools/dom/templates/html/impl/impl_CSSStyleDeclaration.darttemplate
+++ b/tools/dom/templates/html/impl/impl_CSSStyleDeclaration.darttemplate
@@ -3139,6 +3139,15 @@
     setProperty('font-weight', value, '');
   }
 
+  /** Gets the value of "gap" */
+  String get gap =>
+    getPropertyValue('gap');
+
+  /** Sets the value of "gap" */
+  set gap(String value) {
+    setProperty('gap', value, '');
+  }
+
   /** Gets the value of "grid" */
   String get grid =>
     getPropertyValue('grid');
@@ -4192,6 +4201,15 @@
     setProperty('right', value, '');
   }
 
+  /** Gets the value of "row-gap" */
+  String get rowGap =>
+    getPropertyValue('row-gap');
+
+  /** Sets the value of "row-gap" */
+  set rowGap(String value) {
+    setProperty('row-gap', value, '');
+  }
+
   /** Gets the value of "rtl-ordering" */
   String get rtlOrdering =>
     getPropertyValue('rtl-ordering');
diff --git a/tools/dom/templates/html/impl/impl_DataTransferItem.darttemplate b/tools/dom/templates/html/impl/impl_DataTransferItem.darttemplate
index ca64994..42e643d 100644
--- a/tools/dom/templates/html/impl/impl_DataTransferItem.darttemplate
+++ b/tools/dom/templates/html/impl/impl_DataTransferItem.darttemplate
@@ -9,12 +9,19 @@
   Entry getAsEntry() {
     Entry entry = _webkitGetAsEntry() $#NULLSAFECAST(as Entry);
 
-    if (entry.isFile$NULLASSERT)
+    if (entry.isFile$NULLASSERT) {
       applyExtension('FileEntry', entry);
-    else if (entry.isDirectory$NULLASSERT)
+      applyExtension('webkitFileSystemFileEntry', entry);
+      applyExtension('FileSystemFileEntry', entry);
+    } else if (entry.isDirectory$NULLASSERT) {
       applyExtension('DirectoryEntry', entry);
-    else
+      applyExtension('webkitFileSystemDirectoryEntry', entry);
+      applyExtension('FileSystemDirectoryEntry', entry);
+    } else {
       applyExtension('Entry', entry);
+      applyExtension('webkitFileSystemEntry', entry);
+      applyExtension('FileSystemEntry', entry);
+    }
 
     return entry;
   }
diff --git a/tools/dom/templates/html/impl/impl_DirectoryEntry.darttemplate b/tools/dom/templates/html/impl/impl_DirectoryEntry.darttemplate
index 98cced4..1e31f90 100644
--- a/tools/dom/templates/html/impl/impl_DirectoryEntry.darttemplate
+++ b/tools/dom/templates/html/impl/impl_DirectoryEntry.darttemplate
@@ -19,6 +19,9 @@
   DirectoryReader createReader() {
     DirectoryReader reader = _createReader();
     applyExtension('DirectoryReader', reader);
+    applyExtension('WebKitDirectoryReader', reader);
+    applyExtension('webkitFileSystemDirectoryReader', reader);
+    applyExtension('FileSystemDirectoryReader', reader);
     return reader;
   }
 
diff --git a/tools/dom/templates/html/impl/impl_DirectoryReader.darttemplate b/tools/dom/templates/html/impl/impl_DirectoryReader.darttemplate
index b643159..ab4f199 100644
--- a/tools/dom/templates/html/impl/impl_DirectoryReader.darttemplate
+++ b/tools/dom/templates/html/impl/impl_DirectoryReader.darttemplate
@@ -12,11 +12,18 @@
     _readEntries((values) {
       values.forEach((value) {
         applyExtension('Entry', value);
+        applyExtension('webkitFileSystemEntry', value);
+        applyExtension('FileSystemEntry', value);
         Entry entry = value as Entry;
-        if (entry.isFile$NULLASSERT)
+        if (entry.isFile$NULLASSERT) {
           applyExtension('FileEntry', entry);
-        else if (entry.isDirectory$NULLASSERT)
+          applyExtension('webkitFileSystemFileEntry', entry);
+          applyExtension('FileSystemFileEntry', entry);
+        } else if (entry.isDirectory$NULLASSERT) {
           applyExtension('DirectoryEntry', entry);
+          applyExtension('webkitFileSystemDirectoryEntry', entry);
+          applyExtension('FileSystemDirectoryEntry', entry);
+        }
       });
       completer.complete(new List<Entry>.from(values));
     }, (error) {
diff --git a/tools/experimental_features.yaml b/tools/experimental_features.yaml
index 9aa634d..3ca32be 100644
--- a/tools/experimental_features.yaml
+++ b/tools/experimental_features.yaml
@@ -131,6 +131,9 @@
   super-parameters:
     help: "Super-Initializer Parameters"
 
+  macros:
+    help: "Static meta-programming"
+
 # Experiment flag only used for testing.
   test-experiment:
     help: >-
diff --git a/tools/gn.py b/tools/gn.py
index dccae52..fe4718d 100755
--- a/tools/gn.py
+++ b/tools/gn.py
@@ -215,6 +215,9 @@
                                     (gn_args['target_cpu'] != 'arm') and
                                     sanitizer == 'none')
 
+    # Use mallinfo2 if specified on the command line
+    gn_args['dart_use_mallinfo2'] = args.use_mallinfo2
+
     if gn_args['target_os'] == 'linux':
         if gn_args['target_cpu'] == 'arm':
             # Default to -mfloat-abi=hard and -mfpu=neon for arm on Linux as we're
@@ -490,6 +493,11 @@
         '-s',
         type=str,
         help='Comma-separated list of arch=/path/to/sysroot mappings')
+    parser.add_argument('--use-mallinfo2',
+                        help='Use mallinfo2 to collect malloc stats.',
+                        default=False,
+                        dest='use_mallinfo2',
+                        action='store_true')
 
 
 def AddCommonConfigurationArgs(parser):